beauty: a lingua franca for environmental law? benjamin j. richardson*, emily barritt** and megan bowman*** abstract: this article investigates whether beauty can be a global language to inform environmental governance, such as by providing shared values and collaborative approaches across and within different cultures. because art mediates how many people experience environmental aesthetics, such as through photography and music, this enquiry extends to the arts. as is the case for other aesthetic values, beauty is ultimately about relationships and ways of knowing our environment, and the law can best engage with such values through interpretive guidance and process participatory decision making. prescriptive codification of beauty ‘standards’ is generally not a realistic goal for lawmakers. the article enriches our understanding of how aesthetics can contribute to human beings’ emotional empathy and ethical commitment to environmental stewardship, but also identifies some conceptual and methodological difficulties that militate against beauty being a lingua franca for environmental law. keywords: aesthetics; art; beauty; environmental law; language; nature . the enquiry * faculty of law, university of tasmania, hobart (australia). email: b.j.richardson@utas.edu.au. ** the dickson poon school of law, king's college london, london (united kingdom (uk)). email: emily.m.barritt@kcl.ac.uk. *** the dickson poon school of law, king's college london, london (uk). email: megan.bowman@kcl.ac.uk. this article is inspired by and draws on the discussions at the workshop on 'environmental aesthetics: beauty and decision-making', held at the dickson poon school of law, king's college london (uk), on nov. . can beauty contribute to a global language for environmental law? scholars of transnational environmental law have generally overlooked this question; perhaps because of apprehensions about the frivolity of such an inquiry, the difficulty of articulating beauty as a legal standard, or concerns about the degree to which aesthetic values such as beauty are subjective and often imbued with sexist, racist, colonialist, and class-privileged ideas. it is our contention that whilst these concerns are legitimate, beauty nevertheless is a vital element in the pervasive human desire for aesthetic experiences in nature, and it must be reckoned with in environmental governance. beauty may be a matter of cultural relativism but the law should help forge socially defensible judgements about beauty in environmental decisions through informed, participatory processes. concomitantly, through its capacity to engage people’s emotional commitments to environmental causes, beauty can strengthen social action and political willingness to legislate. an underlying assumption of this article is the value of a lingua franca for environmental law. given that environmental impacts often have transnational or regional dimensions, we need a common understanding of relevant issues and solutions across societies and jurisdictions, and this depends upon shared terminology. the united nations’ sustainable development goals (sdgs) evoke this ideal, but it runs through the history of environmental law. the united nations educational, scientific and cultural organization (unesco) convention concerning the protection of the world cultural and natural heritage (world heritage convention (whc)) emphasizes protection of natural and cultural heritage of ‘outstanding universal value’, which necessarily acknowledges such a value can be shared by humanity across different cultures and histories. in short, finding common ground contributes to more effective environmental governance, such as by lessening costly disputes and motivating collective efforts. on beauty specifically, evolutionary psychology suggests that humankind has some shared aesthetic preferences, as in landscape features and animal characteristics, which could provide the kernel to a global language of natural beauty. concomitantly, that literature suggests humankind possesses a see http://www.un.org/sustainabledevelopment/sustainable-development-goals. paris (france), nov. , in force dec. , available at: http://whc.unesco.org/en/conventiontext. ibid., art. . r.o. prum, the evolution of beauty (doubleday, ). http://whc.unesco.org/en/conventiontext shared capacity for moral judgements, which could be further building blocks to a shared aesthetics that values nature beyond its material benefits. legal philosopher john finnis, a defender of natural law theory, defined a set of seven basic ‘goods’ that bring value to human lives that the law should protect and nurture, with these basic goods offering reasons for why we do things. one of these basic goods is the opportunity for aesthetic experiences, and experiencing beauty specifically, which bring pleasure and value to our lives beyond basic living needs. environmental law, however, remains hindered by an incomplete language to meet this goal, despite progress made through the discourses of ‘sustainable development’, ‘intergenerational equity’, ‘common heritage of humankind’, and other meta-norms. these discourses have helped build some common ground, but gaps and weaknesses remain because of vague or inconsistent terminology, the presence of rival concepts and, crucially, the habitual reliance on scientific and economic methodologies that can fail to elicit deep emotional commitment to the issues. this problem is not unique to environmental law, as other fields of governance such as international human rights are permeated by different languages that reflect rival values or perspectives. however, exploring the wider significance of this issue in other legal fields and comparing them to environmental law is beyond the scope of our article. beauty is a subset of the wider domain of aesthetic values, and commentators have long identified it as the most enduring and significant aesthetic value, especially concerning the natural environment. much of the ensuing discussion about beauty is thus framed by the broader scholarly debates about aesthetics. as a noun, aesthetics relates to the philosophy of the interpretation of art and nature. as an adjective, and in the vernacular, it describes human perception and emotional responses to such phenomena. all individuals have the capacity for aesthetic judgements. could it thus be concluded that a nigerian and german, for example, can similarly admire a beautiful roaring waterfall or an exquisite bird of paradise despite not understanding one another’s tongue, and that this mutual affection might translate into demands for stronger legal protection? such a concept would be too simplistic because judgements about beauty (and other aesthetic values) are culturally mediated and function alongside m. hauser, moral minds: the nature of right and wrong (harper, ). j. finnis, natural law and natural rights (oxford university press, ), pp. - . see, e.g., g. santayana, the sense of beauty: being the ouline of aesthetic theory (dover publications, ); p. guyer, values of beauty: historical essays on aesthetics (cambridge university press, ). for an introduction, see j.w. manns, philosophy and aesthetics (routledge, ). competing values such as science and economics. yet, we argue it is possible for beauty to play a larger role in environmental governance in certain circumstances, especially with community-based arts and allied institutional reforms that foster public participation. beauty is the most commonly distilled aesthetic value in environmental law because it is considered a positive value through which to protect and nurture our environment. the world heritage convention, to illustrate, safeguards ‘areas of outstanding universal value from the point of view of … natural beauty’, and the united kingdom's (uk) national parks and access to the countryside act was established ‘for the purpose of preserving and enhancing the natural beauty’. our surroundings can also evoke the alter ego of beauty, namely the 'ugly', such as industrial blight and unsympathetic architecture. hence, aesthetic values across wild and human-modified environments are diverse and affiliated to our varied emotional portfolio. this article focuses on beauty not only because of its explicit affirmation in environmental law but also due to its powerful hold in human culture and psychology. beauty is valorized in many realms of our lives, including romantic courtship, fashion, housing design, and recreational pursuits from a sunset beach stroll to an art gallery visit. given that economic and scientific dogma often dominate environmental governance, it should not be a surprise that most environmental lawyers ignore natural beauty, along with other aesthetic values. exceptions to this indifference include john costonis, whose icons and aliens: law, aesthetics and environmental change investigated aesthetics in urban development regulation in the united states (us), and tim bonyhady's the colonial earth, which examined artistic portrayals of the australian landscape in the emergence of its environmental laws. andreas philippopoulos-mihalopoulos touches on aesthetics in his extensive writings including in his spatial justice: body, lawscape, atmosphere. cultural heritage law scholarship also sometimes engages strongly with aesthetics, such as ben boer’s work. the occasional journal article ventures into this subject, such as alice palmer's analysis of aesthetic criteria in world heritage convention n. above, art. . , c. , - geo , s. ( ). r. plum, the evolution of beauty: how darwin's forgotten theory of mate choice shapes the animal world — and us (doubleday, ); a. marwick, a history of human beauty (bloomsbury, ). j. costonis, icons and aliens: law, aesthetics and environmental change (university of illinois press, ). t. bonyhady's the colonial earth (melbourne university press, ). a. philippopoulos-mihalopoulos, spatial justice: body, lawscape, atmosphere (routledge, ). b. boer & g. wiffen, heritage law in australia (oxford university press, ). decision-making, and afshin akhtar-khavari's interpretation of edvard munch's the scream as an exemplar of our primeval fear of nature's darker forces. the absence, however, of more literature in this field betrays the sentiment felt by many that aesthetic values, especially beauty, are, at best, marginal considerations and, at worst, superficial criteria unable to match the ‘objectivity’ and ‘rigour’ of science or economics. beauty, we believe to the contrary, provides an important modality or process of building relationships with nature. aesthetic values matter for their potential to foster less materialistic environmental relationships, to elicit new insights into natural values and impacts, and to generate ethical constraints to human environmental behaviour. artists can creatively represent environmental values and impacts that may be imperceptible or marginalized. in slow violence, rob nixon encourages artists to deploy ‘their imaginative ability and worldly ardour to help amplify the media-marginalized causes of the environmentally dispossessed’. similarly, benjamin j. richardson in time and environmental law believes ‘artistic gestures [can] vividly arouse’ public awareness of ‘our strained relationships with nature that need repair’. of course, aesthetics with or without artistic intervention cannot comprehensively underpin all environmental governance, not only since it needs other inputs such as scientific knowledge (for example, to understand how to mitigate climate change) but also because aesthetic values themselves elicit conceptual and methodological difficulties. this article is equally attentive to evaluating the obstacles to incorporation of beauty (and, potentially, other aesthetic values) into environmental law. these obstacles principally include: ( ) limitations in the type of information that beauty can convey in environmental decision making, such as for nature conservation or pollution control; ( ) difficulties of codifying beauty into workable legal standards, such as in deciding where to locate wind farms, and furthermore the problems of anthropocentric biases that can result in a legal bifurcation of nature into ‘special’ and ‘ordinary’ beauty categories; and ( ) whether and how beauty can be reconciled with other, non-aesthetic values, notably scientific and economic a. palmer, 'legal dimensions to valuing aesthetics in world heritage decisions’ ( ) ( ) ( ) social and legal studies, pp. - . a. akhtar-khavari, 'fear and ecological (in)justice in edvard munch’s the scream of nature' ( ) ( ) nordic journal of law and social research, http://jlsr.tors.ku.dk/issues/nnjlsr- . r. nixon, slow violence and the environmentalism of the poor (harvard university press, ), p. . b.j. richardson, time and environmental law: telling nature’s time (cambridge university press, ), p. . values, in environmental governance. thus, our enquiry into the role of beauty in environmental law considers both the opportunities and obstacles. devoted to mapping 'big picture' themes and highlighting examples, this article spans five parts. the next examines key theories of environmental aesthetics, and beauty specifically. part evaluates existing legal recognition of aesthetic values, focusing on beauty, and canvasses several jurisdictions to illustrate broad patterns. thereafter, part evaluates opportunities and obstacles for using beauty in environmental law. the article concludes in part with advice about the future legal status of beauty. . conceptualizing beauty in environmental aesthetics to understand how beauty has been conceptualized, we must first delve into its wider framing in the literature on environmental aesthetics. this part highlights the relevance of beauty in a range of environmental decision-making contexts, and traces the efforts of scholars and artists to define beauty and to delinate its social purposes. environmental aesthetics are ways of knowing and being immersed in our surroundings, observed gregory bateson, one of the great th-century anthropologists. his aesthetically conceived ecology postulated that ecosystems are informational and communicating systems, like a mind, rather than just flows of material and energy. to think ecologically, we must recognize ourselves as embedded in that system, argued bateson. yet, in our urban demography and globalizing world, this aspiration is not easily realized. the expanding spatial and temporal scales of phenomena such as the impacts of global warming or marine plastic pollution, which can manifest far from the environs we inhabit, obscure our awareness of the aesthetics of environmental change. the arts, however, can help enrich how we experience that aesthetically conceived ecology, even on a planetary scale. nasa’s earliest photographs of earth — most famously, the iconic blue marble taken in december by the apollo crew — helped boost the emerging global environmental movement. over the past half-century, environmental-focused visual art and music has flourished into diverse genres including social activist strands tackling climate change and other sustainability given the expertise of the authors, these examples are largely from common law jursidictions. g. bateson, steps to an ecology of mind (university of chicago press, ). r. kelsey, ‘reverse shot: earthrise and blue marble in the american imagination’, in e.h. jazairy (ed.), scales of the earth (harvard university press, ), , at , . concerns. environmental aesthetics, in other words, are experienced through cultural lenses, often intermediated through the arts and linked to other social processes including the law itself. the importance of environmental aesthetics to our emotional affinity with nature is recognized by major international environmental organizations. the international union for conservation of nature (iucn) affirms in its founding statute that: 'natural beauty is one of the sources of inspiration of spiritual life, and the necessary framework for the needs of recreation'. in , unesco declared that protecting nature's beauty was 'necessary to the life of men (sic) for whom they represent a powerful, physical, moral and spiritual regenerating influence, while at the same time contributing to the artistic and cultural life of peoples'. similarly, the operational guidelines for the world heritage list refer to ‘cultural landscapes’ that ‘are illustrative of the evolution of human society and settlement over time’. yet, we must also acknowledge the reciprocity of this relationship, namely how aesthetics can motivate humans to feed nature's wellbeing, perhaps by fostering less materialistic relationships and instilling ethical constraints on human behaviours or decisions. closer to a less anthropocentric stance, the earth charter of declares 'the protection of earth's ... beauty is a sacred trust' and calls on signatories to 'secure earth’s bounty and beauty for present and future generations'. yet, different people do not experience beauty or other aesthetic qualities identically, which may have implications for the development of a lingua franca based on such concepts. to illustrate, the famous mount fuji astonishes tourists as beautiful scenery but those who practice shintoism may be drawn more to a different aesthetic trait associated with its spiritual significance. a similar dyadic m. miles, ‘representing nature: art and climate change’ ( ) ( ) cultural geographies, pp. - . statute of the international union for the conservation of nature and natural resources (iucn), oct. , preamble, available at: https://www.iucn.org/sites/dev/files/iucn_statutes_and_regulations_january_ _final- master_file.pdf. unesco, recommendation concerning the safeguarding of the beauty and character of landscapes and sites, dec. , preamble, available at: http://portal.unesco.org/en/ev.php- url_id= &url_do=do_topic&url_section= .html. guidelines on the inscription of specific types of properties on the world heritage list, world heritage centre / , jan. , available at: http://whc.unesco.org/archive/opguide - annex -en.pdf. the notion of ‘cultural landscapes’ is recognised in world heritage listing criteria since . preamble and principle . , available at: http://earthcharter.org/discover/the-earth-charter. unesco, ‘fujisan, sacred place and source of artistic inspiration’ (unesco, ), available at: http://whc.unesco.org/en/list/ . interpretation infuses landscapes occupied by indigenous peoples: what might be a beautiful, unpeopled 'wilderness' to a foreigner is a cultural landscape to its aboriginal custodians. in a decision of the supreme court of canada, citizens of the ktunaxa nation objected to the grant of planning permission for a ski resort, on the basis that the development would drive out grizzly bear spirit, a principal spirit within the ktunaxa belief system. more frequently encountered aesthetic divergences relate to artistic taste: admirers of rembrandt’s the night watch may be repulsed by marcel duchamp’s equally iconic urinal. modern architecture is often similarly controversial: the centre pompido in paris (france) and the bt tower in london (uk) are abhorred and admired in equal measure. in contrast to the foregoing efforts to understand beauty through a socio- cultural lens, some philosophers of aesthetics have sought to distill the elements of beauty through formalistic models. their aim is not to study how human beings empirically perceive works of art or natural landscapes but to delineate normatively how they ought to. in the th century, william hogarth postulated that beauty correlates with principles that include uniformity, simplicity and variety. taking a physiological approach, edmund burke defined beauty through one’s emotional reactions, such as pleasurable feelings of tranquillity and euphoria, which he contrasted to the discomfort of sublimity, such as the awe felt by witnessing powerful natural forces. immanuel kant focues on having the correct attitude, namely that appreciation of beauty requires separating aesthetic value from any interest in the object as a means of fulfilling some utilitarian end. non-western cultures have also explored the philosophy of aesthetics. islamic theologians associate beauty with three structural components — order, wisdom and harmony — as expressed most eloquently in irrigated gardens. in east asia, d. bird rose, nourishing terrains: australian aboriginal views of landscape and wilderness (australian heritage commission, ). ktunaxa nation v. british columbia (forests, lands and natural resource operations), scc m. duchamp, fountain, ; v. van gogh, irises, . a. lange, ' seven leading architects defend the world’s most hated buildings', the new york times (style magazine), june , available at: https://www.nytimes.com/interactive/ / / /t-magazine/architects-libeskind-zaha- hadid-selldorf-norman-foster.html. w. hogarth, the analysis of beauty: written with a view of fixing the fluctuating ideas of taste (w. strahan, ). e. burke, philosophical inquiry into the origin of ours ideas of the sublime and beautiful, p. guyer (ed.), ( original, oxford university press, ). i. kant, critique of the power of judgment, p. guyer & e. matthews (trans.) [original , cambridge university press, ). e.c. clark, 'the islamic garden: history, symbolism, and the qur'an', in v.j. comell (ed.), voices of islam (greenwood publishing, ), chapter . some traditional philosophy emphasizes the oneness between nature and culture, such as the sacredness of landscapes (shintoism) and spiritual freedom when journeying through them (daoism). theories about environmental aesthetics specifically have surged recently, focusing on what and how to evaluate aesthetic values in the world at large, from rugged wilderness to urban environments. three distinct themes exist in the literature. one is arnold berleant’s call for an ‘aesthetics of engagement’, which stresses a participatory and intimate experience with the subject matter as the best way to appreciate its aesthetic values. although his approach helpfully supports greater public participation in direct sensory engagement with our natural surroundings, and cultivation of place-based cultural affiliations, the emphasis on personal engagement implies that what and how we aesthetically appreciate nature is just subjective taste; we thus might have no guidance to differentiate between serious and trivial aesthetic judgements. a second, alternate idea is the 'cognitive' model, pioneered by allen carlson, who asserts that proper aesthetic appreciation depends on a scientific understanding of natural phenomena derived from botany, biology, ecology, and cognate disciplines. science, contends carlson, steers the viewer to the points of aesthetic significance, such as botanical knowledge that allows the viewer to fully enjoy floristic patterns and colours. but emily brady argues that the cognitive model excludes common emotional responses to natural beauty: like observing a golden sunset or thunderous waterfall, for which one does not need any scientific expertise to appreciate. a third understanding of environmental aesthetics are the critical, politically-charged perspectives that advocate interpretation of aesthetic values that contribute to social change such as better environmental policies. activist scholars such as alan braddock and t.j. demos champion social justice and ecological sustainability as vital criteria for how we should view nature’s aesthetics and their depiction through artistic practices. this stance also is critical of the privileging of western constructions of ‘nature’ in eco-aethetics, which can also marginalize the ‘other’ such as aboriginal cultural values. j. ramsay, the aesthetic value of landscapes: background and assessment guide (icomos-ifla international scientific committee on cultural landscapes, ), pp. - . a. berleant, living in the landscape: toward an aesthetics of environment (university press of kansas, ). a. carlson, aesthetics and the environment: the appreciation of nature, art and architecture (routledge, ). e. brady, aesthetics of the natural environment (edinburgh university press, ), pp. - . a.c. braddock, ‘ecocritical art history’ ( ) ( ) american art, pp. - , at . environmental aesthetics, explains demos, must thus be a way to ‘decolonize nature’ and forge a more egalitarian world. the role of the arts in mediating our experience of natural aesthetics has a long history. in our urban demography, we often aesthetically engage with nature vicariously rather than directly —through david attenborough-narrated films, lavish coffee-table books or soothing nature sounds cds. artistic interpretations of natural beauty through visual art and music have also been conceptualized in the literature around certain artistic conventions and theoretical positions. in the western world, the romantic era during the th and th centuries helped render a more benign view of nature through several pictorial styles. the ‘picturesque’ iconography evoked gorgeous panoramas such as majestic snow-capped mountains, while the ‘sublime’ exalted nature’s wildest, untamed tendencies such as stormy seas or deep canyons. another seminal style is the ‘pastoral’ landscape, dotted with manicured gardens and pastures adorned with peaceful livestock. with the surge in activist eco-art in the late th century, researchers have also enquired into the appropriate purpose of aesthetic experiences. beginning in the s, the land art movement (also known as earth art) resisted the commodification of art by abandoning museums and galleries to create monumental landscape projects, such as robert smithson's iconic spiral jetty ( ) carved into a utah lake. in recent decades eco-art has occupied other public spaces to forge new narratives about global environmental challenges such as climate change and air pollution, as evident in the work of the climart group. music is also increasingly used to explore natural aesthetics, for reasons that range from cultivating a ‘sense of place’ (via nature soundscape recordings) to musical compositions that aid in social awareness for the environment. t.j. demos, one leading voice here, has advocated the arts to forge creative and critical insights that challenge the political orthodoxy of neoliberal globalization and to foster solutions to the planetary environmental crisis. further, many environmental organizations use beauty to generate public support for their causes, from saving whales to wilderness, as exemplified in the next part. t.j. demos, decomolizing nature (sternbery press, ). c. casaliggi & p. fermanis, romanticism: a literary and cultural history (routledge, ), pp. - . b. tufnell, land art (tate, ). see at: http://www.climart.info. a.s. allen & k. dawe (eds), current diretions in musicology: music, culture, nature (routledge, ). t.j. demos, decolonizing nature: contemporary art and the politics of ecology (sternberg press, ). the aesthetics of beauty have also been intensely investigated with regard to human beings themselves, which illustrates how strongly beauty is culturally mediated. much literature has sought to empirically validate some universal indicia of beauty across different cultures, of which one identified criterion is facial symmetry. but other evidence shows sexist and racist influences. patriarchal cultures have imposed cruel stereotypes of beauty, such as the practice of foot- binding young girls in pre-communist china and corset wearing in victorian britain. naomi wolf's the beauty myth argued that idealistic social standards of physical beauty persist because of commercial influences through the 'beauty industry'. racism also influences perception of human beauty; one abhorrent example being the nazi regime’s attempts to breed an aryan master race. thus, whilst humankind has a shared interest in beauty, its appreciation may be more influenced by cultural context than by the innate qualities of objects. in addition to philosophical enquiries into appreciation of beauty and environmental aesthetics, researchers have investigated their influence on human environmental attitudes, well-being and behaviour. studies in environmental psychology highlight how aesthetic stimuli, such as beautiful colours, complexity and fragrance, may reduce personal stress. the health council of the netherlands found positive associations for the health of people living near attractive greenery. research has found psychological benefits associated with a variety of environmental experiences, including visiting city parks, urban gardens, and wildernesses. by contrast, unattractive built environments can overload inhabitants with demanding, stressful, or mundane features. the relevance of such research for our enquiry is that by linking environmental beauty to human benefits we can build a stronger political case for an aesthetics-based environmental law. e.g., k. grammer & r, thornhill, 'human (homo sapiens) facial attractiveness and sexual selection: the role of symmetry and averageness' ( ) ( ) journal of comparative psychology, pp. - . l. frost, ‘“doing looks”: women, appearance and mental health', in j. arthurs & j. grimshaw (eds), women's bodies: cultural representations and identity (bloomsbury, ), pp. - , at . n. wolf, the beauty myth (chatto and windus, ). health council of the netherlands, nature and health: the influence of nature on social, psychological and physical well-being (health council of the netherlands and dutch advisory council for research on spatial planning, ). r.a. fuller, et al., "psychological benefits of greenspace increase with biodiversity’ ( ) ( ) biology letters, p. . n. dunnett & m. qasim, ‘perceived benefits to human well-being of urban gardens’ ( ) horttechnology, pp. - . s. kaplan & j.f. talbot, 'psychological benefits of a wilderness experience', in j. altman & j.f. wohlwill (eds), behavior and the natural environment (plenum, ), pp. - . also releant here is social psychology research into how aesthetic values can contribute to pro-environmental behaviour, as explored in section . of this article. the foregoing discussion leads to several conclusions about beauty for environmental governance. firstly, it is an important social value but significant debate persists about the appropriate normative criteria for evaluating beauty in environmental contexts. secondly, interpretation of beauty is culturally mediated, especially through art, which itself is subject to theoretical contestion and, thirdly, aesthetic values including beauty can be deployed for utilitarian purposes, from personal therapeutic benefits to political activism. the next part considers how notions of beauty, and sometimes aesthetics more generally, have informed legal governance as a precursor to understanding the areas where further work is needed in part in order to elevate beauty to a more substantial pillar of environmental governance. . legal context . . mapping patterns of interaction the law does not stand 'outside' beauty or other aesthetic values but partakes in shaping their enunciation and meaning. these values feature in many contexts governed by environmental law. proposals to establish wind turbine farms have strained land use approval processes across europe and north america because of community uproar over anticipated visual and acoustic impacts. perceptions of scenic beauty frequently drive the establishment of national parks even while indigenous peoples may associate such areas with their ancestral cultural heritage. indeed, conservation management in australia and sweden, among many jurisdictions, is increasingly intertwined with the aesthetic values of indigenous peoples, whose importance is acknowledged in the united nations declaration on the rights of indigenous peoples, whereby: 'indigenous peoples have the right to maintain and strengthen their distinctive spiritual relationship with their s.l. martin, ‘wind farms and nimbys: generating conflict, reducing litigation' ( - ) fordham environmental law review, pp. - . m. adams, 'beyond yellowstone? conservation and indigenous rights in australia and sweden', in g. cant, a. goodall & j. inns (eds), discourses and silences: indigenous peoples, risks and resistance (university of canterbury, new zealand, ), pp. - . new york, ny (us), sept. , available at: http://www.un.org/esa/socdev/unpfii/documents/drips_en.pdf. traditional ... lands'. another context is ecological restoration, where regulators must consider future aesthetic values. a challenge found in restoration projects in scotland and the netherlands is that some stakeholders find the change toward an 'untamed' nature less beautiful than their former bucolic surroundings. in post- mining rehabilitation, aesthetic values also matter greatly for future land uses and improving the appearance of the landscape, as evident in south africa's mining industry. nonetheless, while aesthetic values including beauty inform many environmental governance contexts, this does not mean that such values are priorities for lawmakers. instead, scientific and economic precepts dominate environmental regulation for reasons that range from their seeming objectivity and precision in setting legal standards, to the political influence of those who promote such disciplines. any cursory check of environmental legislation reveals so: australia’s lodestar environment protection and biodiversity conservation act (cth) refers to ‘aesthetics’ just once (and contains no references to ‘beauty’) but has entries for 'economics' and for 'science' or 'scientific'. similarly, listings of threatened species commonly reflects scientific advice on their conservation status rather than their charm or inherent value, while pollution standards generally are based on scientific evidence of potential hazards and the economic costs of alleviating them. concomitantly, the language of 'beauty' itself is increasingly missing from environmental governance beyond hortatory statements, as researchers have found in the evolution of british landscape planning legislation. the seeming arbitrariness of aesthetic values also frustrates courts where community opinion expects the law to reflect intelligible standards: as one us judge bemoaned, 'aesthetic considerations are fraught with subjectivity. one man's pleasure may be another man's perturbation. ... judicial forage into such a nebulous area would be chaotic'. to make sense of these disparate permutations, we can delineate several distinctive ways in which beauty as an aesthetic value interacts with environmental law, namely as: ( ) a 'resource' for advocates of stronger law; ( ) a ibid., art. . j. prior & e. brady, 'environmental aesthetics and rewilding' ( ) ( ) environmental values, pp. - . d. limpitlaw & a. briel, ' post-mining land use opportunities in developing countries: a review' ( ) ( ) journal of the southern african institute of mining and metallurgy, pp. - . p. selman & c. swanwick, 'on the meaning of natural beauty in landscape legislation' ( ) ( ) landscape research, pp. - . ness v. albert, s.w. d at ( ). substantive element of legal doctrine such as rules or standards that prescribe aesthetic criteria; ( ) an expression of state sovereignty over nature, and thus access to environments for conservation or development purposes; and ( ) an attribute of institutionalized processes including courts and public inquiries that deal with environmental law. . . beauty as an advocacy gesture proponents of better environmental laws frequently deploy aesthetic criteria, especially beauty, in nature conservation campaigns, to attract political support and community donations. even the world’s first national park, established at yellowstone (us) in , owes partly to the painter thomas moran and photographer william henry jackson, whose enticing images of it helped win us congressional support. they established a precedent, with depictions of scenic wilderness and charismatic wildlife often in the communications of contemporary environmental groups. environmental advocates may also invoke 'negative' aesthetics, such as images of unsightly deforestation or pollution, for similar purposes. greenpeace's on-going campaign to save whales uses evocative footage to solicit public empathy for their plight. in australia, campaigns to stop dams and forestry have relied heavily on sensuous imagery of threatened 'pristine wilderness', such as peter dombrovskis' photographs of tasmania's franklin river at risk of a proposed hydro-power development in the early s. one consequence is that areas or species that benefit from such tactics may leave ‘ordinary’ (unbeautiful) nature without commensurate legal protection. another consequence is social; unsightly development may be shifted to areas occupied by less affluent communities. equally, the discourse of exalted ‘wilderness’ values may exclude their human history. some of these tensions are evident in current controversies over wind energy projects with local communities are fearful of the noise or visual impacts of turbines in their vicinity which might render their environs less ‘beautiful’. yet, climate-conscious activists usually advocate wind farms as a source of renewable n. strochlic, ‘we have a painter to thank for yellowstone’, national geographic magazine, apr. , available at: http://www.nationalgeographic.com/magazine/ / /explore-thomas- moran-yellowstone-paintings. a. kalland, unveiling the whale: discourses on whales and whaling (berghahn books, ), p. . t. bonyhady, ‘no dams: the art of olegas truchanas and peter dombrovskis,’ in r. butler (ed.), the europeans: Émigé artists in australia – (national gallery of australia, ), pp. - . j. good, 'the aesthetics of wind energy' ( ) ( ) human ecology forum, pp. - . energy, and welcome legislation to fast-track project approvals, as adopted in ontario (canada), through the green energy act , for instance. conversely, some jurisdictions, such as the state of victoria (australia), have given greater weight to the aesthetic concerns of impacted local communities. difficult issues thus arise over the distribution of the aesthetic, ecological, and economic costs and benefits of wind turbines. we address the problem of how to weigh aesthetic values with other policy criteria proposed for environmental law in the next part. . . beauty in environmental law doctrine we now turn to investigate how environmental law doctrine specifically embraces beauty in its rules, standards, and adjudicative practice. the contexts include landscape management, biodiversity conservation, ecological restoration, and pollution control. the law may direct regulators to protect areas of extraordinary natural beauty, to curb unsightly developments or to remediate malodorous pollution that can impair beauty. statutory references to aesthetic standards are typically cursory, and often framed around general legislative goals rather than practical regulatory standards. for instance, the uk’s countryside and rights of way act provides for the designation of 'areas of outstanding natural beauty' (aonb) but does not define 'natural beauty'. this task thus shifts to supplementary policy guidance as developed through public consultation, with the result of which is that natural beauty is predominantly defined with reference to the ‘character’ of the landscape as evident in hedge rows, mature trees, archaeological ruins, topography, and so on. as of december , there are aonb in the uk, covering about % of its land. in the us, the antiquities act enables the president to create, by proclamation, national monuments from federal lands to safeguard notable cultural and natural features. while this statute does not explicitly authorize protection of lands for their scenic beauty or other aesthetic attributes, its implementation has extended to such goals. other s.o. , c. , sched. a. e. de wit & a. guild, 'winds of change: wind farm amendments to victorian planning schemes' (norton rose fulbright, mar. ), available at: http://www.nortonrosefulbright.com/knowledge/publications/ /winds-of-change-wind- farm-amendments-to-victorian-planning-schemes. , c. , ss. - . selman & swanwick, n. , above, pp. - . statistics from landscapes for life are available at: http://www.landscapesforlife.org.uk. pub. l. - , stat. . see further, c.a. klein, ‘preserving monumental landscapes under the antiquities act’ ( ) cornell law review, pp. - . related us legislation which does explicitly identify aesthetic criteria for protecting federal public lands include the wilderness act and the federal land policy and management act , both of which refer to ‘scenic’ values as goals for protection. aesthetic values of individual species can also solicit legal protection. the us bald eagle protection act protects a creature that has been the country’s national emblem since , while the endangered species act protects threatened species for reasons that include the preservation of their ‘esthetic….value to the nation and its people’. another example is environmental legislation that acknowledges aesthetic values such as beauty but without using such values as criteria for decision making. for instance, new zealand’s te urewera act , which gives legal personhood and protection to about , hectares of a former national park, describes the reconstituted sanctuary as ‘ancient and enduring, a fortress of nature, alive with history; its scenery is abundant with … remote beauty’. no part of this legislation turns on specific criteria of beauty, and the legislation itself primarily addresses maori grievances rather than safeguarding natural beauty. another way in which legislation can acknowledge environmental aesthetics is by regulating activities that might infringe them. the minnesota environmental rights act provides for civil remedies to protect ‘natural resources’, which it defines to include ‘scenic and esthetic resources’. it has been left to the courts however, ‘to define authoritative criteria for the evaluation’ of such aesthetic values. legislation obliging environmental restoration, such as of former mines and brownfield sites, also commonly includes aesthetic criteria: ontario’s mining act stipulates that ‘aesthetics are … [an] important’ objective when planning rehabilitation of former open pit mines. in practice, aesthetic criteria are applied in rehabilitating ontario’s numerous abandoned pits and pub. l. - , stat. . usc, ss. - . the act was later amended to include another species, and is now known as the bald and golden eagle protection act, usc - c. pub. l. no. - , stat. , usc s. (a)( ). public act , no. , s. ( ). minnesota statutes ( ) ss. b. , subdivision . t. murphy, ‘environmental law: protection of scenic and aesthetic resources under the minnesota environmental rights act—state ex rel. drabik v. martz, n.w. d (minn. )’ ( ) ( ) william mitchell law review, pp. - , at . mining act, r.s.o. , c. m. , ontario regulation / , cl. . quarries, with one stakeholder observing in that ‘the main objective of the work is to the sits safer, more productive, and more aesthetically appealing’. protection of beauty also features in the adjudication of disputes. the tort of private nuisance, for example, protects a property owner’s use and enjoyment of her land and requires courts to balance aesthetic considerations, community interests and utility, in deciding whether to prohibit nuisance activities. generally, courts are unwilling to accept mere unsightliness as an actionable wrong. this is exemplified in a recent decision of the supreme court of vermont (us), where the impact of a commercial solar array on an area’s ‘rural aesthetic’ was deemed insufficient to constitute a nuisance. instead, private nuisances are largely decided on the basis of olfactory and aural criteria which can be more objectively assessed and thus avoids courts taking on the uneasy role of ‘arbiters of style and taste.’ examples do exist of courts being less anxious about engaging with complex aesthetic considerations. in a decision of the high court of south africa, the court elevated an aesthetic complaint to one about the value of the property, which enabled it to find that the installation of a thatched roof amounted to a private nuisance. in the us, courts have adjudicated claims about the beauty of a particular area in relation to zoning decisions and administrative challenges to the exercise of the government power of eminent domain (that is, to take private property for public purposes). in the growing body of jurisprudence relating to climate change, us courts have acknowledged that ‘aesthetic and environmental wellbeing, like economic wellbeing, are important ingredients of the quality of life.’ applicants have evoked ugly imagery such as sewage-soaked carpets and the ‘black dead spikes’ of fire-decimated forests in order to demonstrate an injury in fact (a requirement of standing) in challenges to state inaction on greenhouse lanark stewardship council (lsc), a place in time: te natural resoucres of lanmark council (lsc, ), p. . g.p. smith ii, ‘the price of beauty: an economic approach to aesthetic nuisance’ ( ) ( ) harvard environmental law review, pp. - , at - ; however, visual asethetics have been found relevant in terms of access to natural light (regan v. paul properties dpf no ltd [ ] ewca civ ) and the notorious ‘sight’ of sex workers (thompson-schwab v. costaki [ ] wlr (ca)). myrick v. peck electrival company, vt ( ). ibid. waterhouse properties v. hyperception properties [ ] zafshc . smith ii, n. above, pp. - . washington environmental council v. bellon f. d ( th cir. ) gas (ghg) emissions. judicial confidence in introducing aesthetic criteria into legal doctrine is therefore mixed, but not beyond the realms of possibility. international environmental law also acknowledges aesthetic criteria sporadically. it does so most emphatically in the world heritage convention with 'outstanding … natural beauty' being one stipulated criterion for properties to be included in the world heritage list. yet, the term ‘natural beauty’ is defined not in the legislation but through supplementary guidance. unesco, which administers the convention, had advised that there is no formal classification system of 'natural beauty' and its operational guidelines for the convention give little elaboration other than to explain that it means ‘exceptional natural beauty and aesthetic importance’. similarly, the council of europe’s european landscape convention of , acknowledges in its preamble the importance of landscapes of ‘outstanding beauty’ but does not contain any other provisions that explicitly refer to aesthetic values although they certainly can be implied as highly relevant. interestingly, the convention extends to ‘landscapes that might be considered outstanding as well as everyday or degraded landscapes’, thus recognizing that culturally valuable landscapes including aesthetic values should not be confined to the stereotypically scenic. . . aesthetics of state sovereignty over nature the third way in which the legal system may interact with beauty, and other environmental aesthetics, is by embodying them in expressions of state sovereignty rather than in the regulation of environmental activities and impacts as such. such use of environmental aesthetics is sometimes ambiguous, equally capable of interpretation as a symbol of respect for nature as of its subjugation. sovereign legal authority has long been expressed through symbols that draw on aesthetic imagery, which often make reference to beautiful animals and plants. they appear frequently on coat-of-arms, bank notes and coins, and national flags. the australian coat-of-arms features a kangaroo and emu, while india’s includes a lion. greenland has the polar bear, and swaziland an elephant. national julian v. united states f. supp. d ( ) n. above, art. . unesco, operational guidelines for the implementation of the world heritage convention (july ), p. , available at: https://whc.unesco.org/archive/opguide -en.pdf. florence (italy), oct. , in force mar. , available at: https://rm.coe.int/ . ibid., preamble. ibid., art. . currency is similarly filled with natural iconography, such as the elephants and giraffes on zimbabwe’s bank notes and the zebra on rwanda’s. likewise, many sovereign flags display environmental features associated with their country, such as the maple leaf (canada), condor (ecuador) and turtle (cayman islands). in some case, prominent species have become politicized symbols of sovereign authority and national culture, as with the charistmatic panda bear for china and its international practice of ‘panda diplomacy’ to win political favours. music is also used to articulate sovereign authority, notably through melodious national anthems that affirm state authority (for example, the british anthem beginning with ‘god save the queen’). another aesthetic expression of state authority, albeit one not tied explicitly to beauty, is cartography. official maps can serve to stamp government authority on territory and subjects, thereby exerting control over any indigenous peoples (for instance, by deeming their lands to be terra nullius) and over 'wilderness' and other environmental spaces to be colonized for nation building. by demarcating boundaries and dividing geographies, maps aid in excluding or granting access to natural resources and determining how they will be governed. the spatial representation of nature through maps can violate ecological (and cultural) relationships as legal authority is mapped according to different political and historical exigencies. this is illustrated by the long-standing mismanagement of australia’s murray-darling river basin, which became highly degraded owing to governance arrangements attuned more to the territorial claims of competing australian state governments than the holistic ecological relationships with the huge river basin. maps matter, as they contribute symbolically to the legitimacy of governmental authority. environmental law thus functions within a cartographic expression of sovereign authority that influences the options available to its regulators. . . aesthetics in legal process and dialogue decision-making fora such as courts, public inquiries, treaty conferences and secretariats, shape the aesthetics of environmental law. these governance spaces evoke their own material aesthetics and articulate aesthetics-informed dialogue h. nicholls, the way of the panda. the curious history of china’s political animal (pegasus, ). j. branch, the cartographic state: maps, territory and the origins of sovereignty (cambridge university press, ); k. miles, 'insulae moluccae: map of the spice islands, ', in ij. homhann & d. joyce (eds), international law's objects (oxford university press, ), forthcoming. d. connell, water politics in the murray darling basin (federation press, ). about the issues they consider. this understanding of environmental aesthetics as embedded in institutionalized relationships of cultural and ecological salience dovetails with the regulatory insights of others who have touched on this topic, such as andreas philippopoulos-mihalopoulos. the material aesthetic includes public consultation processes that engage participants with aesthetic imagery (for example, posters and brochures), the decorum of public environmental inquiries and tribunals such as judges’ attire and courtroom layout (often informal compared to regular courts), and presentation of scientific evidence in such fora (including maps and photos of environmental impacts). public inquiries and environmental assessment procedures sometimes include site visits to places where participants can engage directly with specific aesthetic contexts. for instance, new zealand’s waitangi tribunal, which considers maori grievances relating to rights to control natural resources and other issues connected with the treaty of waitangi, often makes field trips to sites of significance in claims. aesthetic considerations also arise in legal discourses. much environmental governance emanates from institutionalized community consultation and stakeholder engagement, and these processes can by virtue of their terms of reference, methods and member composition become a valuable means to articulate and debate aesthetic values. such institutional processes can have particular traction in communities whose sense of place is at stake. case law also reveals the presence of aesthetic character in legal reasoning, where legal arguments are embellished with ‘rhetoric, metaphor, form, images and symbols’. martha nussbaum believes that law can be investigated as an aesthetic product in its own right, as a form of literature, and she encourages greater use of narratives in legal reasoning that evoke sympathy for the cause, which is lacking in other models of legal reasoning with a more abstract and technical style lack. the british judge lord denning was master of this juridic poetry, evoking iconic visions of bluebell woods and english summertime as a prelude to his legal analysis. the foregoing remarks obviously cover a lot of ground, so we will illustrate them in more detail with a further example —an important australian court case philippopoulos-mihalopoulos, n. above. g. watt, dress, law and naked truth (bloomsbury, ). waitangi tribunal, ‘tribunal site visit, wairau’, available at: https://teara.govt.nz/en/photograph/ /tribunal-site-visit-wairau. d. manderson, songs without music: aesthetic dimensions of law and justice (university of california press, ), preface. m. nussbaum, poetic justice: the literary imagination and public life (beacon press, ). hinz v. berry [ ] qb ; miller v. jackson [ ] qb . over a proposed wind farm. heard by the new south wales land and environment court, the litigation pitched the public benefits of green, renewable energy against the aesthetic impacts on the community which would host wind turbines. in approving the development, chief justice brian preston cited the principle of intergenerational equity as a prevailing consideration in a project that would help address climate change. in gauging the aesthetic impacts on the historic village of taralga and its vicinity, the court reviewed five photomontages depicting how the turbines might look from different locations. it also gathered evidence from a site inspection and heard from three ‘visual impact assessment experts’. all this was in addition to the assessment of the aesthetic issues during the government’s initial approval of the project, which included an environmental impact study that attracted submissions from the general public and non- governmental organizations (ngos), of which opposed the project and raised some concerns. the court grappled at great length with how to comprehend the visual and sonic impacts in legally cognizable language. chief justice preston began by noting that ‘insertion of wind farms into a rural landscape involves interrupting the rural and natural cohesion of that landscape’. yet, he found the evidence of the ‘visual impact assessment experts’ to ‘ultimately [be] of little assistance as there was no agreement between [them]’. he then considered whether the project could be modified, such as by fewer or repositioned turbines, but concluded that this might render the project ‘uneconomic’. he also rejected requests for monetary compensation for property owners affected by the ‘blight’ of the wind farm, concluding that the claim would ‘strike at the basis of the conventional framework of landuse planning’. the noise impacts, in contrast, were much easier for the court to adjudicate because technology allows for precise quantification of noise levels, and the availability of governance standards are available, such as the 'south australian environmental noise guidelines: wind farms’, which the court considered. in sum, the taralga wind farm case shows how different aesthetic values resonate in legal discourse unevenly, and how the processes used to understand them, spanning site visits, commissioning expert evidence and public taralga landscape guardians inc v. minister for planning and res southern cross pty ltd [ ] nswlec ( feb. ). ibid., para. . ibid., para. . ibid., para. . ibid., para. . submissions, might resist definition or comparison in legally intelligible standards. we take this enquiry further in the following part and evaluate systematically the principal challenges to including beauty in environmental law decisions, and discuss how to overcome them. . beauty: a viable value for environmental law? . . what knowledge and values can beauty convey to environmental governance? thus far, we have explained the importance of beauty as a key aesthetic value, emphasizing its socio-cultural context and the philosophical debates that give rise to interpretatons of beauty as a decision-making criterion. we have considered how beauty, and aethestic criteria more broadly, shape environmental law in matters of legal doctrine, political advocacy for stronger laws, institutional processes, and as expressions of state sovereignty. we now turn to the key challenge of ascertaining or evaluating the value of beauty in the context of environmental law. the issue is that a beautiful aesthetic relationship imparts diverse knowledge and values, both potentially positive and negative, for environmental governance. beauty can fortify emotional and ethical commitments to nature stewardship but also detract from them and even invite unscrupulous manipulation. thus, to guide our enquiry we pose three subsidiary questions. firstly, what knowledge and values can beauty convey to environmental governance, such as for nature conservation or pollution control? secondly, can, and should, beauty be codified into functional legal standards? thirdly, can beauty be reconciled with other non-aesthetic values in governance, such as scientific and economic values? proponents of natural beauty postulate that it strengthens emotional empathy for environmental causes, primarily because human beings have biophilic instincts, as harvard biologist edward o. wilson argued. eco-art can facilitate such compassion, by shaping ‘public conception of “unknowable” spaces that are beyond the reach and view of the average person’. where governance solicits public participation, such as in community-based land care, such r. lumber, m. richardson & d. sheffield, ‘beyond knowing nature: contact, emotion, compassion, meaning, and beauty are pathways to nature connection’ ( ) plos one, https://doi.org/ . /journal.pone. . e.o. wilson, biophilia (harvard university press, ). g. kolb & j. needham, 'antarctic dreams' ( ) ( ) exposure, pp. - , at . emotional connection might nurture participants' fidelity. in contrast, while science and economics supply ample reasons to safeguard nature's bounty regardless of its 'beauty', these phlegmatic disciplines may be less successful in emotionally engaging us. no doubt, science can stir passions, as witnessed by fiery debates over genetically modified organisms and climate change predictions. economic policy can generate similar visceral feelings, especially regarding poverty and inequality. but these disciplines tend to arouse us on mostly intangible or abstracted concerns regarding fear of health impacts or economic hardship, rather than to focus human emotions on specific localities or landscapes, as do aesthetic values such as recognition of beautiful scenery. environmental behavioural models in the social psychology literature have verified empirically how opportunities to appreciate the aesthetic values of nature, especially via artistic representation and community arts, can stimulate pro- environmental behaviour, such as by fostering awareness of the consequences of one’s behaviour, unfreezing ingrained, adverse habits, and fostering social cooperation on environmental challenges. beauty may thus fortify ethical constraints on our environmental behaviour. one pioneer of ecological ethics, aldo leopold, suggested this when hypothesizing that: 'a thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. it is wrong when it tends otherwise'. thus natural beauty can be interpreted as a non-instrumental value and, following akhtar-khavari, its artistic expressions of it can help foster 'less anthropocentric conceptions of matter and the natural world'. such claims however depend on the relationships and knowledge of participants in specific contexts. we might even find ‘beauty’ in ghastly environs, depending on the artistic interpretation: the sublime imagery of industrialized china in edward burtynsky's manufactured landscapes can captivate the viewer with 'beautiful' devastation. wind farms or solar arrays, as noted earlier, can blight the landscape in the eyes of some but beautifully express our commitment to a safer climate. emily brady suggests that active community relationships with, rather than just observations of nature, such as via ecological restoration and ghd, multiple benefits of landcare and natural resource management (final report for the australian landcare council, ), pp. - . d.j. curtis, ‘using the arts to raise awareness, and communicate environmental information in the extension context’ ( ) ( ) journal of agricultural education and extension, pp. - . a. leopold, a sand county almanac (oxford university press, ), p. (emphasis added). akhtar-khavari, n. above, p. . j. baichwal, edward burtynsky: manufactured landscapes, (zeitgeist films, ). community gardening, can foster eco-centric ethical commitments. even so, aesthetics is surely only one of several overlapping bases for ethical valuation of nature, which include theories about intergenerational equity and intrinsic values. not only might we perversely find ‘beauty’ in ecological damage; beauty can directly motivate wantonness. animals have long been hunted for their furs, feathers, tusks and other aesthetic 'commodities' in our desire to decorate our bodies and homes, often with the imprimatur of the law. plants do not escape either, with orchids and other pretty species pillaged by collectors. taxidermy displays in natural history museums and hunters’ trophy lodges memorialize the aesthetics of vanquished wildlife. blending science and spectacle, taxidermy attained its apotheosis in the th century landscape diorama providing viewers with life-like, three-dimensional displays of colonized nature. the persecution of the beautiful inhabits many cultures, not just western societies; native americans traditionally adorned themselves with furs and feathers as symbols of chiefly status. beauty might thus be a lingua franca of humanity’s desire to dominate nature as much as protect it. even when we desire to restore damaged ecologies, our aesthetic preferences might clash with nature's best interests. lay people might perceive as messy and unruly a rewilding ecosystem as messy and unruly whereby forest fires, fallen trees, or animal carcasses are left to perform their regenerative roles. british academics jonathan prior and emily brady identify two such examples in europe. one is the oostvaardersplassen reserve in the netherlands, where the 'de-domestication' of introduced species such as heck cattle and konik ponies is occurring on km of polder reclaimed in . in the name of rewilding, the wildlife have been left to the vagaries of nature, which in some instances has led to mass die-offs during winter food shortages — a negative aesthetic for animal welfare groups who tried unsuccessfully to challenge in court the reserve's management. another example is the restoration of scotland’s carrifran wildwood: the project led by an ngo to rewild a denuded valley to its condition e. brady, 'aesthetic regard for nature in environmental and land art' ( ) ( ) ethics, place and environment, pp. - . s.t. asma, stuffed animals and pickled heads: the culture of natural history museums (oxford university press, ). a.m. demeo, 'access to eagles and eagle parts: environmental protection v. native american free exercise of religion' ( ) hastings constitutional law quarterly, pp. - . prior & brady, n. above. j. lorimer & c. driessen, 'wild experiments at the oostvaardersplassen: rethinking environmentalism in the anthropocene' ( ) ( ) transactions, pp. - . see further: j. lorimer & c. driessen, 'experiments with the wild at oostvaardersplassen' ( ) ( - ) ecos, pp. - , at . of , years ago has been controversial for some in the local community. they prefer the area's existing aesthetic and recreational values associated with open, pastoral countryside to the uncertain future aesthetics of a forest that will take a few centuries to fully mature. this controversy has played out more extensively across the uk with george monbiot criticizing the national trust's adoration of the highland moors of wales and scotland, which, he points, out were once verdant forests until logged or grazed to destruction. finally, the seductive qualities of beauty can manipulate public opinion, as the business sector knows well. in the name of 'corporate social responsibility' (csr), contrived aesthetics figure prominently in businesses' campaigns to convince consumers to buy products or services for their supposed green credentials. advertisements for cars, which may highlight their fuel efficiency or other 'eco-benefits', typically show drivers cruising unhurriedly through magnificent, unhurried countryside, as though motor vehicles belong with the trees and animals rather than to congested, polluted highways. deceitful aesthetics can get even more repugnant: the dupont chemical company, one of the largest us polluters, in unveiled its new double-hulled oil tankers with advertisements that featured seals and other marine life clapping their flippers or wings in applause to the tune of beethoven’s ode to joy. as toby miller shows in greenwashing culture, such hubris, is not confined to selling corporate wares.. it manifests in hollywood’s 'green celebrities', whose jet-setting lifestyles impose a huge eco-footprint, and corporate sponsorship of museums, art galleries and in other cultural institutions by firms with poor eco-credentials (such as bp’s patronage of london's tate gallery for years in defiance of climate change activists). corporate green washing should concern environmental lawyers because governance trends over recent decades which have ceded greater self- responsibility to business actors amplify risks of unscrupulous practices that can weaken environmental performance. see further at: http://www.carrifran.org.uk. g. monbiot, 'why are britain's conservation groups so lacking in ambition?', the guardian, oct. , available at: https://www.theguardian.com/environment/georgemonbiot/ /oct/ /uk-carnivores- rewild-wolves-bison-conservation. the advertisement is available at, see at: http://www.youtube.com/watch?v=zjzffelrcjs. t. miller, greenwashing culture (routledge, ). n. khomami, 'bp to end tate sponsorship after years', the guardian, mar. , available at: https://www.theguardian.com/artanddesign/ /mar/ /bp-to-end-tate-sponsorship- climate-protests. the foregoing suggests that beauty is a two-edged sword. it enriches environmental decision making, from the levels of individual emotional empathy through to social cooperation. but beauty can also serve less desirable behaviours—corporate green washing or community resitance to ecological restoration projects that defy expectations of beauty. these considerations thus highlight the importance of legal institutions in influencing how beauty informs environmental behaviour. for instance, corporate greenwashing can be curbed if laws are enforced to prevent misleading advertising. public participation in decision-making can be critical to mediating a community’s distaste for aesthetically challenging eco-restoration activities. law can make the difference between the positive and negative connotations of beauty from the perspective of the health of the biosphere. . . can and should beauty be codified into functional legal standards? if a society values its aesthetic relationships with fauna, flora and landscapes, can it codify them into governance standards? current legal practice suggests the answer is no if the expectation is a prescriptive, laundry list of beauty attributes. although human beings show strong propensities to mould their surroundings to their aesthetic taste, from garden design to urban architecture, the language of aesthetics does not easily convert into legal formulae. indeed, it seems preposterous to imagine rigid legal standards of natural beauty based on tree girth and height, water hue, or species composition. british landscape planning has largely jettisoned the statutory language of protecting ‘natural beauty’ in favour of landscape ‘character’ assessments. as noted earlier, in international law the world heritage convention’s operational guidelines shed little guidance on what ‘outstanding natural beauty’ means. some aesthetic attributes are potentially measureable and definable, such as ambient noise and cultural heritage; yet the quality of beauty itself is more elusive. many jurisdictions possess detailed regulations on acceptable noise levels because they can be precisely measured through acoustic technologies and explained through expert evidence. as a result, courts are content to adjudicate private disputes on the basis of quantifiable aesthetic values whereas they tend to eschew ‘notoriously subjective and selman & swanwick, n. above. unesco, n. above, cl. (vii). j. stewart, et al. (eds), why noise matters: a worldwide perspective on the problems, policies and solutions (earthscan, ). personal’ discussions about what is ‘pretty’ or ‘beautiful’. similarly, laws to safeguard historic heritage such as buildings and archaeological ruins use indicia like rarity and representativeness to justify protections, although we may disagree whether such criteria denote ‘beauty’. more specifically, three challenges must be managed if we expect the law to codify beauty. firstly, judgements of beauty are strongly personality- and culture-bound. secondly, standards of beauty change, as societies change and, thirdly, codification of beauty might favour protection of ‘special’ nature at the expense of the ‘ordinary’. firstly, because of the common assumption that the human response to aesthetics is subjective rather than rational or factual, judgements of beauty can be viewed as deficient. colloquially, this means ‘beauty is in the eye of beholder’. however, some evidence to the contrary exists. research suggests a shared, cross- cultural preference for landscapes that resemble homo sapiens’ evolutionary cradle, the african savannah. psychologists also identify a shared desire for fractal patterns ‘that repeat at increasingly fine magnifications’ such as clouds, tree lines and coastlines. water also is a near-universal attractant for people. such commonalities however do not preclude cultural variations in aesthetic tastes. as noted earlier, we disagree on wind farms, and indigenous environmental managers can read different aesthetic values in landscapes to their non-indigenous counterparts. all this is apart from the underlying uneasiness many legal theorists, from ‘crits’ to legal realists, have with any belief that the law can objectivly reflect social norms in unequal and pluralistic societies. thus, judgements of beauty seem to have a biological basis but can manifest in diverse ways in cultural contexts. secondly, because standards of beauty change, the question arises whether the law should follow or shape aesthetic preferences, especially given they can shift quite dramatically as the following anecdote shows. the tasmanian devil (sarcophilus harrisii), inhabiting the australian island of tasmania, was in the th century described by one colonial writer as a ‘very ugly, savage and mischievous cornelis dorland v. anna aletta smits [ ] zawchc . boer & wiffen, n. above. d. dutton, the art instinct. beauty, pleasure, and human evolution (bloomsbury, ), passim; j. appleton, the experience of landscape (wiley, ), pp. - . j. briggs, fractal patterns: the patterns of chaos (touchstone, ). w. nichols & c. cousteau, blue mind (back bay books, ). r.m. unger, law in modern society (the free press, ). little beast, and had incurred private and government bounties to hasten its demise. yet, the marsupial carnivore is now a beloved tourist ambassador and in became the state’s official animal emblem. the species received legal protection in owing to its rarity, but this had seemingly little impact on its aesthetic appeal, which only shifted decisively into positive territory over the last few decades. a similar story could be told about the european wolf, now enjoying a renaissance in countries where it was persecuted as vermin until recently. the law is not irrelevant to these shifting aesthetic relationships, yet neither can it be particularly instrumental if its role is simply to prescribe an animal’s conservation status (pest or protected) rather than to cultivate community knowledge about wildlife and their stewardship. thirdly, attempting to codify beauty risks stratifying nature into ‘special’ versus ‘ordinary’ categories to the potential detriment of the latter. the aesthetic values that tend to captivate us most are frequently associated with ‘specialness’ — mount fuji, the grand canyon or the pyramids of giza. the world heritage convention and its domestic law variants evoke that sentiment, and we can hardly deter societies wishing to protect their most esteemed natural and cultural heritage. however ‘specialness’ has drawbacks: species should be protected before they become so endangered or rare as to move us; and pretty landscapes are not necessarily more ecologically valuable than the ‘mundane’ grasslands or swamps. ‘specialness’ should also trouble us if it serves to bifurcate the human and natural worlds. even human-dominated urban landscapes can provide refuges for resilient wildlife and, conversely, nature is a cultural landscape not a wilderness. the ‘special’ versus ‘ordinary’ bias in judgements of natural beauty also highlights that anthropocentric taste can be damaging when determining the level of environmental protection. beauty may thus amount to no more than another human-serving, utilitarian criterion, at odds with the push by deep ecologist thinkers to respect the intrinsic values of nature. accordingly, if we are to leverage action through environmental aesthetics, we must cultivate beauty or other aesthetic values more widely than just within c.a. meredith, my home in tasmania: during a residence of nine years, volume (john murray, ), p. . a.d. smith, ‘on the trail of the wolf, europe’s much maligned and misunderstood predator’, the guardian jan. , available at: https://www.theguardian.com/environment/ /jan/ /wolf-maligned-predator-poland- carpathians. h. doremus, ‘the special importance of ordinary places’ ( ) ( - ) environs, pp. - . t. low, the new nature (penguin, ). l. vikka, the intrinsic value of nature (rodopi, ). nature’s ‘special’ enclaves. artists can aid here by helping people to re-imagine aesthetic values and relationships in our environs: some artists have photographed amazing beauty in obscure fungi on the forest floor or recorded evocative nature soundscapes, while others have enlightened us about the character of humble marine invertebrates rather than majestic whales, or revealed the evocative and ephemeral impacts of human breath on natural materials like limestone. furthermore, artist collaborations with environmental lawyers and political groups, such as the climarte group in australia, show how environmental art can occupy public spaces to forge new socio-legal narratives about global environmental challenges and solutions. in meeting the foregoing three challenges, it becomes clear that the law seemingly cannot codify timeless and universal standards of natural beauty, however that does not mean beauty cannot be an important pillar of governance for a given community at a specific point in time. fiona reynold’s recent book the fight for beauty gives examples of how some british communities have cited beauty to improve environmental governance, such as their successful campaign in the s to stop forestry authorities creating ugly (and biologically damaging) conifer plantations on moorland landscapes. likewise, communities across europe have stopped wind farms in eu natura sites, in which aesthetic and biological criteria have dovetailed. it would therefore seem that beauty can be a positive lingua franca in specific legal contexts even if it cannot be a global language. . . can we reconcile beauty with non-aesthetic values in environmental governance? there are clear challenges for beauty to become its own global language, and we must further acknowledge that obstacles exist to beauty 'communicating' with the e.g. work of stephen axford: discussed in j. davis, ‘micro fungi of australia: in pictures’, the guardian june , available at: https://www.theguardian.com/artanddesign/gallery/ /jun/ /photography-fungi. see the artistic portrays of coral reefs by alex mckenzie and miranda lowe: royal museums greenwich, ‘who are the radical fun advisors’, sept. : available at: http://www.rmg.co.uk/discover/behind-the-scenes/blog/who-are-radical-fun-advisors. see work of inés cámara leret, available at: http://www.inescamaraleret.com. see at: http://www.climarte.org. f. reynolds, the fight for beauty (oneworld, ), pp. - . european commission, eu guidance on wind energy development in accordance with the eu nature legislation (european union, ), available at: http://ec.europa.eu/environment/nature/natura /management/docs/wind_farms.pdf. different languages that inhabit environmental law, notably the natural sciences and economics that commonly occupy its centre-stage. their vernacular, evoked through concepts and methods such as the precautionary principle, conservation status, cost-benefit analysis, and financial incentives, not only neglect aesthetic values but may also conflict directly with them. yet, public participation and social justice are strongly endorsed values in many legal instruments, such as the unece convention on access to information, public participation in decision-making and access to justice in environmental matters (aarhus convention). hence, it would be problematic to ignore the popular interest in experiencing aesthetic values or to reserve judgements of beauty to any self-proclaimed experts of aesthetic taste. to illustrate this quandary, let us briefly return to the australian wind farm litigation discussed in section . . the court had to adjudicate over the alleged visual and acoustic sequelae of proposed wind turbines, with such impacts weighed against other law-mandated considerations including biodiversity impacts (including bird strikes), the provision of renewable energy to combat global warming, and possibly non-environmental considerations such as job creation. clearly, the court had a daunting task. economists like to believe that they can reconcile such disparate factors through cost-benefit analysis, yet such approaches are problematic due to the necessary human judgements (biases) in determining the monetary values to assign. conceivably, the court could have come to a variety of decisions, ranging from prioritizing the aesthetic impacts to ignoring them. legislation could make life easier for judges by ranking in advance the relative importance of different factors, but judicial discretion can never be entirely eliminated, and local and novel circumstances frequently require bespoke solutions. the problem of reconciling divergent values in legal governance is brought into sharp relief by systems theory, which conceptualizes modern society as acephalous, centrifugal and polycentric, functioning through semi-autonomous subsystems such as the market and government bureaucracy, each with its own language and protocols. sociologist niklas luhmann describes these subsystems as ‘autopoietic’, implying that each has evolved its own lingua franca, and therefore can respond to issues defined only within that language. these aarhus (denmark), june , in force oct. , available at: http://www.unece.org/env/pp/welcome.html. d. kysar, regulating from nowhere (yale university press, ). see n. luhmann, ecological communication (university of chicago press, ); n. luhmann, the differentiation of society (columbia university press, ). n. luhmann, social systems (stanford university press, ). http://www.unece.org/env/pp/welcome.html conditions make it difficult for society to govern environmental challenges in an integrated manner through different subsystems, including science (ecological knowledge) and market forces (economic values). this insight has led some legal scholars, such as gunther teubner and eric orts, to propose a model of ‘reflexive law’ that eschews expectations that the law, as a subsystem itself, can meld all other subsystem values into a single modality. instead, the law should stimulate a culture within companies, government agencies and other actors that encourages internal learning and behavioural change. to illustrate this process, the law could oblige companies to publicly report on their environmental performance, and that reporting process might in turn encourage corporate managers to learn more about their company's environmental impacts, and then their financial implications for the business, and finally to take corrective action. all this would occur without top-down edicts from the regulator to reduce pollution or whatever the desired environmental outcome. systems theory does not however suggest rigid boundaries separating different spheres of society but rather maintains that cross-overs depend on finding common language or means of translating different ideas. so, what would the foregoing mean for the incorporation of aesthetics with other factors in environmental regulation? bricolage governance might ensue through process-oriented standards such as public inquiries that foster dialogue among different constituencies representing aesthetic values, scientific expertise, and economic incentives. yet, this could easily lead to outcomes that favour the most well-resourced and 'noisy' advocates. equally problematic would be to commodify environmental aesthetics into the language of economics, a trend already evident in csr 'green washing', which can lead to unacceptable ecological impacts, for instance, national parks become playgrounds for eco-tourism rather than biodiversity stewardship. a more productive communicative alliance might ensue through involvement of artists as interpretative intermediaries across economic, scientific and cultural domains. evidence exists already of this productive synergy. recent eco-documentary films such as plastic ocean (exposing marine plastic pollution) and the end of the line (challenging global overfishing), as well as older films like al gore's inconvenient truth (addressing climate change), have become a popular g. teubner, law as an autopoietic system (blackwell, ); e.w. orts, ‘reflexive model of environmental regulation’ ( ) ( ) business ethics quarterly, pp. - . strategy for eco-artists and scientists to collaboratively shape public discourse. likewise, the collaboration between the london-based artist alex mckenzie and scientist miranda lowe from natural history museum, has successfully forged new interpretative guidance on coral reefs and their need for greater protection. such collaboration in fact has much older vintage: artists regularly joined scientists in the ‘age of discovery’ of european overseas exploration, with artistic renderings of newly discovered plants and animals, and landscape drawings, that were instrumental in dissemination of scientific knowledge. these partnerships, no doubt, may also foster narratives that marginalize certain perspectives and issues, as plastic ocean allegedly does. this suggests that the law must help structure interdisciplinary dialogue through transparency standards and interpretative guidance, which this article’s conclusion further reflects on. the law does not sit outside these collaborative ventures. social activism is fostered within engineered spaces such as public museums, art galleries and civic parks, and these spaces are created and supported by governments through land-use planning schemes, arts funding, freedom of expression laws, and diverse other mechanisms. . conclusion some of the foregoing discussion might lead one to conclude that beauty should be banished from environmental law. but that is not our intention. aesthetic taste is undeniably deeply ingrained in human nature, but manifests diversely through personal and cultural contexts. nature is more than a material resource for economic sustenance, as it partakes in aesthetic relationships whose emotional and ethical dimensions can improve humankind and our fellow creatures with whom we share the biosphere. the purpose of this article is not to 'solve' how environmental law should deal with beauty, but rather to map the key issues, challenges and future directions. we probably cannot codify environmental beauty into any stable or precise legal formulae that have timeless or universal application. however, sometimes a specific community will articulate and deliberate over a particular l. henderson, ‘q&a: a plastic ocean – can a movie help us see this invisible crisis?’, the conversation, june , available at: http://theconversation.com/qanda-a-plastic-ocean-can-a- movie-help-us-see-this-invisible-crisis- . royal museums greenwich, n. above. e.g., the french-sponsored, baudin scientific expedition to australia: j. fornasiero, l. lawton & j. west-sooby (eds), nicolas baudin’s voyagers - (wakefield press, ). aesthetics-based environmental position, for example to oppose an ugly waste dump or to conserve a treasured landscape, which the law can respond to. hereby, a lingua franca arises, albeit not on a global scale, and the community’s concerns can be codified into legal norms through the terms of a pollution permit, development consent or land use plan, for example. but we should not be despondent about the absence of lingua franca of beauty in other contexts, and indeed there are some reasons why we might avoid trying to create one. acknowledging the wonder of our world and being open to different aesthetic interpretations of natural beauty is surely beneficial, just like the adaptive and dynamic properties of the ecosystems that the law should protect. seeking agreement on what is beautiful might unhelpfully halt the evolution of those values in dealing with new contexts and challenges. science and economics must also be part of the conversation here rather than pushed into separate silos: science can help alert us to the value of ‘ordinary’ nature while economics illuminates the financial winners and losers. the arts must also partake, by marrying different fields of knowledge and raising public awareness of and participation in environmental aesthetics. as the firebrand art theorist t.j. demos recommends, ‘the artist [who] merely draw[s] attention to the problem is not enough; what is needed is further collective mobilization to pressure government institutions’. the law cannot avoid its responsibilities here. even where it is neither possible nor desirable to articulate precise definitions of what is beautiful, the law can help society express its aesthetic relationships with nature. by setting democratic and transparent process standards and interpretative guidance, communities are empowered to know their surroundings better and engage in richer dialogue about aesthetic values. public hearings and environmental assessment procedures provide a starting point, and indeed are already commonly used in some jurisdictions, such as in the uk’s landscape planning. further, participatory processes that help ‘gauge community values’ can in turn empower courts in adjudicating disputes involving culturally complex aesthetic considerations. thus complaints about unlovely activities, such as landfill sights or scrap metal businesses, are not placed outside the realms of justiciability. this is particularly important given that judicial forays into adjudication of the beautiful are enmeshed with economic considerations about property values or dominated by costly aesthetic expertise. opening up aesthetic considerations to demos, n. above, p. . smith ii, n. above, p. . community deliberations democratizes beauty by helping to ensure that it is no longer a value that can be wielded only by the politically privileged. our article is not designed to write blueprints for reform, but we can identify already some interesting precedents that might help tackle some governance challenges. the recently reformed governance framework for the tasmanian wilderness world heritage area (twwha), a huge region covering , km , has forged new ground in accommodating aboriginal aesthetic values, with inclusion of better consultation protocols and shared decision making with local aboriginal representatives. previously, the twwha’s aesthetic values were shaped narrowly around a terra nullius ‘wilderness paradigm’ and a commodified aesthetics catering to eco-tourism. at the international level, as alice palmer has researched, treaty secretariats and conferences on nature conservation and climate change are evolving more space for deliberation about aesthetic values. this might go further, by changing the composition of participating delegations and working with artists to re-imagine how to address the upheavals of the anthropocene. furthermore, this article cautioned that references to natural beauty risk importing an anthopocentric ‘special’ versus ‘ordinary’ dichotomy in environmental protection, thereby undermining efforts over recent decades to shift protection towards an ecocentric approach that upholds nature’s integrity for its own sake. recent new zealand legislative reforms give some natural places their own legal personality, protected by fiduciary regimes that require trustees to speak for those places’ aesthetic and other values. the new zealand reforms were designed not with beauty in mind but rather to settle historical grievances for theft of indigenous territories, but the legal model adopted might be considered analogously to help foster greater respect for nature’s intrinsic value. whether the new zealand model will be less anthropocentric in practice, given that decisions about aesthetic and other values remain the province of a board of trustrees, remains for further enquiry. in sum, beauty is a language by which we enter into aesthetic relationships rather than just admire objects. it may not ever be a global lingua franca, but we tasmania department of primary industries, parks, water and environment (dpipwe), executive summary twwha management plan (dpipwe, ). palmer, n. above. k. sanders, ‘beyond human ownership? power and legal personality for nature in aotearoa new zealand’ ( ) journal of environmental law, http://academic.oup.com/jel/advance- article/doi/ . /jel/eqx / . http://academic.oup.com/jel/advance-article/doi/ . /jel/eqx / http://academic.oup.com/jel/advance-article/doi/ . /jel/eqx / should improve its status in local and transnational environmental law as a vital process that enriches the existing ways of knowing and protecting the biosphere. microsoft powerpoint - hp .ppt pietro faccioli, for the hera-b collaboration università di bologna and infn ppietroietro ffaccioliaccioli, , for the for the herahera--b b collaborationcollaboration università di bologna and infnuniversità di bologna and infn charmonium, open charm and beauty production at hera-b charmonium, open charm and beauty charmonium, open charm and beauty production at heraproduction at hera--bb june , asilomar conference grounds, pacific grove, california june , asilomar conference grounds, pacific grove, california hera-b detector and physics topics results and comparison with previous experiments outlineoutline heavier states and heavier states and feeddownfeeddown to j/to j/ψψ ψ′/ψ and kinematics fraction of j/ψ’s from χc j/j/ψψ productionproduction pt and xf distributions, a-dependence newnew: : decaydecay angularangular distributionsdistributions fraction of j/ψ’s from b decays charmcharm inclusive d , d+, d*+ and ratios a-dependence highest energy among fixed-target experiments often unclear experimental picture, especially for p-a collisions test production models (pqcd + initial/final state interactions in nuclei) largest χc statistics analyzed in hadron collisions largest χc statistics analyzed in hadron collisions first data at negative xffirst data at negative xf observation of low-pt /|xf| effects observation of low-pt /|xf| effects m m m target wires (c, ti, w) target wires (c, ti, w)magnetmagnet trackingtracking good pid good pid (e±, μ±, π, k, p) √s = . gev a = ÷ large acceptancelarge acceptance ( - mrad) high resolutionhigh resolution (top view) electrons fixed nuclear fixed nuclear targettarget the herathe hera--b detectorb detector + photon reconstruction ecalecal muonmuon richrich gev/c protons gev/c protons vertex detector vertex detector mμμ [gev/c ] . . . . . e n tr ie s (a .u .) mμμ [gev/c ] - mee [gev/c ] . . . . . •• j/j/ψψ, , χχcc, , ψψ′′, with a-dependence •• ddoo →→ μμ++μμ−− (fcnc) •• inclusive inclusive bb production •• ϒϒ, , φφ, , ρρ//ωω dilepton trigger: ~ · eventsdilepton trigger: ~ · events ψψ′′ j/j/ψψ ρρ//ωω φφ ϒϒ( s)( s) ϒϒ( ( -- s) s) two independent channels (e+e− + μ+μ−)two independent channels (e+e− + μ+μ−) physics at heraphysics at hera--bb ~ k φφ → kk . . . . mkk [gev/c ] e n tr ie s (a .u .) •• kkss,, kk **,, ΛΛ,, φφ,, ΞΞ++-- • pentaquarks •• ddoo,, dd++,, dd*+*+,, ddss •• j/j/ψψ ~ · minimum bias events~ · minimum bias events ‘hard photon’ trigger: ~ · events ‘hard photon’ trigger: ~ · events e d σ /d p [a .u .] minbias data, run hp trigger, run et [gev] pc → γγx - - directdirect γγ,, ππ oo, , ηη production with four different nuclei e+e− μ+μ−μ+μ− j/j/ψψ and and ψ′ψ′ signalssignals e n tr ie s /( m e v /c ) m(μ+μ−) [gev/c ] . . . . m(e+e−) [gev/c ] e n tr ie s /( m e v /c ) . . . . ~ j/ψ ~ ψ′ σj/ψ ~ mev ~ j/ψ ~ ψ′ σj/ψ ~ mev e+e− full dilepton data sample ( target materials) j/ψj/j/ψψ ψ′ψ′ψ′ μ+μ− j/ψj/j/ψψ ψ′ψ′ψ′ ~ j/ψ ~ ψ′ σj/ψ ~ mev ~ j/ψ ~ ψ′ σj/ψ ~ mev j/j/ψψ productionproduction kinematics: pkinematics: ptt distributiondistribution preliminary data (di-electron channel). compatible results from the di-muon data, not shown here. comparison with p-a results at similar energy (√s = . gev) [a . u .] pt [gev/c] t d dp σ a e (au) e (au) e (au) ccc e /e (be) e /e (be) e /e (be) tititi www e (si) e ( e (sisi)) hera-bherahera--bb [g ev /c ] a increase of with a increase of with a c si ti au w be xxff distributiondistribution preliminary data (e+e−), compared with p-a results at . gev first data centred at negative xf e (be, cu) e e (be, cu)(be, cu) e / (be) e / e / (be)(be) e (si)e e ((sisi)) e (au)e e (au)(au) hera-b (c)hera-b (c) cc titi ww aa--dependencedependence xf e . gev be/fe/w e . gev be/c/cu/w e . gev h /c/ca/fe/w na . gev be/al/cu/ag/w na . gev h /pt e . gev be/fe/w e . gev be/c/cu/w e . gev h /c/ca/fe/w na . gev be/al/cu/ag/w na . gev h /pt α - rr. . vogt, prc ( ) , np a ( ) vogt, prc ( ) , np a ( ) -- k.gk.g. . boreskovboreskov && a.b. a.b. kaidalov, kaidalov, jetpl jetpl ( ) ( ) b&kb&k b&k vogt: final state absorptionvogt: final state absorption models (with variants): . . . . - . - . - . - . . . . . . . . . - . - . - . - . . . . . . . . . . . . . hera-b preliminary (di-muon channel, carbon+tungsten double-wire runs) errors statistical only decaydecay angularangular distributiondistribution: : polarizationpolarization framesframes j/ψ direction in the hadron (p-n) cm frame beam direction in the j/ψ rest frame direction of e +(μ+) as seen in the j/ ψ rest frame θ polarization axis bisector between beam and (–)target directions in the j/ψ rest frame collins-soper (“cs”)gottfried-jackson (“gj”) “beam” helicity “hcm” e , e - , e , e , etc. e , na , etc. cdf, na , etc. il nuovo cimento vol. xxxiii, n. ( ) phys. rev. d , ( ) target direction in the j/ψ rest frame = (-)j/ψ direction in the lab frame refor mula ted as ) ) ) / π / π / π / π π − / / − cos dn d θλ +∝ + ϕλ ϕ ϕ ϕ cosθ ) ( dn d ∝ + cos cos θ λ θ θ example: >ϕλ ( ) dn d d ∝ cos ϕθ sin sin cos sincos+ + +θ ϕθϕ θθ θϕ ϕλλλ (x axis reaction plane)⊥ example: <θλ parametrizationparametrization = θϕλ = θϕλ λλ φφ ~ ~ beambeambeam cscscs hb . gev p-c/ti/w na . gev p-pt/p-h e . gev π±-w p−-w/π−w e . gev p−-be/π−be p−-cu/π−cu hb . gev p-c/ti/w na . gev p-pt/p-h e . gev π±-w p−-w/π−w e . gev p−-be/π−be p−-cu/π−cu / / / / / / // λφ hcmhcmhcm meaningmeaning ofof λλθφθφ the “natural” polarization frame has λλ θφ equal to zero: in such frame the decay distribution is symmetric and is described by only two parameters. polar axisproduction plane =θϕλ <θλ >θλ >ϕλ >ϕλ λλ θφ ≠ means that the axes of the current frame are not principal axes of symmetry for the angular distribution. but it is always possible to define a reference frame with this property: the angular distribution can always be diagonalized to a form with λλ θφ = =θϕλ <θϕλ <θϕλ λλθφθφ in in thethe threethree framesframes [gev/c] λθφ beam cs hcmbeam beam cs cs hcmhcm μ μ+ − + −+e e ,<∼ θϕ θϕϕθ λλ λ,<∼ θϕ θϕϕθ λλ λ preliminary, ⇒ the three frames actually see the decay kinematics from different perspectives cs the best frame? (statistically ~ % correlated) dn d(cosθ) cosθ n μ μ+ − + −e e cosθ λλθθ andand thethe hierarchyhierarchy ofof framesframes beam (arb. norm.) beam beam ((arbarb. norm.). norm.) hcm (arb. norm.) hcmhcm ((arbarb. norm.). norm.) cscscs preliminarydn/d(cosθ) ∝ + λθ cos θdn/d(cosθ) ∝ + λθ cos θ |λθ| |λθ| |λθ| > > μ μ+ − + −+e e preliminary μ μ+ − + −+e e [gev/c] hcm beam cshcm hcm beam beam cscsλθ [gev/c] the data are consistent (for example) with a polarization generated in the cs frame interpretationinterpretation polarization generated polarization generated in the cs framein the cs frame …… and translated into and translated into the hcm framethe hcm frame λθ points = data, lines = toy mc [gev/c] generation in generation in the hcm framethe hcm frame cscs exp cm/ ( gev/ )j cψ ⎡ ⎤=− ⋅ −⎢ ⎥⎣ ⎦θλ p hcm cs hcm hcm cscs λθ the cs frame is the best approximation of the “natural” polarization frame → physics: origin of j/ψ polarization no hypothesis of generation in the hcm fr. can reproduce the data in the cs fr. case case experimental situation: cs frameexperimental situation: cs frame j/ψ significantly polarized at low momentum (low pt and |xf|) λθ e . gev p-cu e . gev π±-c/cu/w na . gev p-h na . gev p-pt hb . gev p-c/ti/w e . gev p-cu e . gev π±-c/cu/w na . gev p-h na . gev p-pt hb . gev p-c/ti/w beam framebeam frame λθ wa . gev π−-be . gev π−-be . gev p-be . gev p-be e . gev p-si e . gev π±-w hb . gev p-c/ti/w wa . gev π−-be . gev π−-be . gev p-be . gev p-be e . gev p-si e . gev π±-w hb . gev p-c/ti/w e / e / p−-w/π−w / p−-be/π−be / p−-cu/π−cu / p−-w/π−w / p−-be/π−be / p−-cu/π−cu / e . gev e . gev hcm framehcm frame polarization almost completely smeared out, except for pt very close to zero λθ e . gev π±-c/cu/w cdf gev p−-p run ii wa . gev π±-w/cu/si na . a gev in-in hb . gev p-c/ti/w e . gev π±-c/cu/w cdf gev p−-p run ii wa . gev π±-w/cu/si na . a gev in-in hb . gev p-c/ti/w ψ′ψ′--toto--jj//ψψ production ratioproduction ratio p-a results consistent within a % variation: no apparent dependence on production energy and kinematics (different xf/y, cosθ windows) slight dependence on the target nucleus: na / / (+ e ) j/j/ ( (w) (ti) )% % c % b b . ± . . ± . . ± . ψψ ψ ψψ σ σ ρ + − + − ′′→ ′ → + − ⎧⎪⎪⎪= =⎨⎪⎪⎪⎩ e e analysis finished. combined results (e+e- + μ+μ-): hera-bherahera--bb hera-bherahera--bb e e e e e e e e e na , na & na na , na , na & na & na na [gev]s e e e e e e e e e b ′σ (ψ ′) /b σ (j /ψ ) (% ) na na na p-a hera-bherahera--bb )(= . ± . ± . % brs j/ j/ j/ j/ j/ + −⎧⎪⎪⎪⎪⎪⎨⎪⎪⎪⎪⎪⎩ + − + − → ′→′ ′→ = × ⋅′ b b b r ψπ πψπ π ψ η ψπ ψ ψψ ψ ψ ρ ψ′ψ′ kinematicskinematics measured relative to the j/ψ distributions: b′σ(ψ′)/bσ(j/ψ) as a function of xf. pt , cosθ hera-b (full stat, e+e-/μ+μ- avg.)herahera--b b (full stat, (full stat, ee++ee--//μμ++μμ-- avg.)avg.) e ( . gev)e ( . gev) na ( . gev)na na ( . gev) e ( . gev)e ( . gev) xf pt [gev/c] ( ) ( / ) . . ′ − = ±jθ θλ ψ λ ψ b ′σ (ψ ′) /b σ (j /ψ ) cosθ b ′σ (ψ ′) /b σ (j /ψ ) measurement: fraction of j/ψ’s from χc: kinematical distributions a-dependence χχcc productionproduction ( ) incl ( j/ ) (j/ ) c irχ σ χ ψγ σ ψc → = ∑ selection: j/χ γψc {e eμ μ + − + − e n tr ie s /( m e v /c ) m(μ+μ−γ)-m(μ+μ−) [gev/c ] background: mixed events after background subtraction from the data, with ± χc’s (μ +μ− + e+e−): r(χc) = . ± . ± . [phys. lett. b , ( )] new data: × bigger χc statistics (the largest analyzed in a hadronic experiment) preliminary / data (di-muon sample) rr((χχcc)) preliminary evaluation ( / data): based on χc’s reconstructed in the di-muon channel (less than % of the total statistics) ( ± )% of the produced j/ψ’s come from χc decays [gev]s (%) ( )cr χ expected final precision cdf cdf ((pp--pp)) isr isr ((pp--pp)) e e ((pp--sisi)) e e ((pp--lili)) e / e / / / ((pp--bebe)) / / prelim.prelim. ππ--aa herahera--bb j/j/ψψ’s from b decays’s from b decays pa → bb x b → j/ψ y → e+e-/μ+μ- y detached j/ψ’s mμμ . ± . . ± . . ± . . ± . μ μ+ − + −e e tot ( ) (j/ ) ( . . ) j % / b n n br ± ← = = ψ ψ - extrapolation to full xf range - normalization by total j/ψ cross sect. - correction by br of b → j/ψ σ(bb) = . ± . stat± . syst nb/nucleon [phys. rev. d , ] σ (b b ) (n b /n u c le o n ) proton energy (gev) n. kidonakis et al.hera-bhera-b e e e e r. bonciani et al. mee e e e e isrisr e / e / n a n a e e e e e e ua ua e e e e na na na na e e / / r r r ⎡ ⎤ ⎢ ⎥= − − − −⎢ ⎥⎣ ⎦ j dir j incl … ψ ψσ σ indirect and direct j/ψ productionindirect and direct j/ψ production ( ± )% χc j/ψ ψ′ j/ψ b j/ψ ( . ± . )% ( . ± . )%(to be improved!) extracted from mb data [ ] ( )± ±stat syst j/ nb/nucl . gev = ψσ pn ( ± )% of the j/ψ’s are produced directly using partial/preliminary hera-b results: curve: nlo nrqcd fit of all data (maltoni et al., hep-ph/ ) p-p p-a kππ inv. mass [gev/c ] e n tr ie s /( m e v /c ) e n tr ie s /( m e v /c ) kπ inv. mass [gev/c ] open charm: reconstructedopen charm: reconstructed signalssignals ± preliminarypreliminary p r e li m in a r y p r e li m in a r y p r e li m in a r y p r e li m in a r y ± d± d*±d +d m(kππ)-m(kπ) [gev/c ] e n tr ie s /( . m e v /c ) ± | ( ) ( )| mevm k mπ − < d | ( ) ( )| mevm k mπ − > d p n d+ k − π+ π+ d k− π+ p n p n d k− π+ π+ +*d d cross sectionsd cross sections d : unclear situation at high √s e result clearly disfavoured energy dependence well described in each case by the function reflecting the behaviour of proton pdfs (lourenço & wöhri) . [ . /( ) ]d sσ ∝ − without e : with e : d +d √ hera-b prel. d± √ hera-b prel. d*± √ hera-b prel. comparison with pwith p--p/pp/p--a resultsa results σ σ σ+ ∗= = dir dir ( ) ( ) ( )d d d cross section ratios: experiments vs. isospin symmetrycross section ratios: experiments vs. isospin symmetry u ↔ d polar. states incl incl( ) / ( . ) . d dσ σ± ±= incl incl( ) / ( . . )d dσ σ∗± ±= pdg averages for d* , d*± → d , d± feeddown brs violated by a factor of . ± . is o s p in s y m m e tr y e x p e r im e n ts u ↔ d d*±/d √ . . .avg ±= hera-b prel. u ↔ d d±/d √ . . .avg ±= hera-b prel. aa--dependencedependence ααavg.avg.((xxff~ ) =~ ) = . ± . . ± . experimental situation (p-a): mass spectra by target material (e.g. for d ): e n tr ie s /( m e v /c ) kπ inv. mass (gev/c ) c ti w ± ± ± (prel. d-meson average) c ti w curves: σpa = σpn·a α consistent with no suppression αα((dd )= . ± . )= . ± . αα((dd±±)= . ± . )= . ± . αα((dd**±±)= . ± . )= . ± . summarysummary j/j/ψψ production production in in pp--aa collisions at √collisions at √ss = . = . gevgev …… …… and its components:and its components: high statistics, clean signals, two decay channels wide kinematical coverage pt up to . gev/c negative xf a-dependence: flat suppression down to xf ~ - . ψ′-to-j/ψ ratio fraction of j/ψ’s from χc fraction of j/ψ’s from b j/ψ’s j/ j/ψψ’s’s χc’s χχcc’s’s ψ′’s ψψ′′’s’s j/ψ’s from b j/j/ψψ’’s from bs from bj/j/ψψ decay decay angular distributionsangular distributions d , d±, d*± inclusive production cross sections and ratios a-dependence consistent with α = open charmopen charm longitudinal polarization rapidly increasing in magnitude with decreasing pt and |xf| strong hierarchy of frames: the direction of the original interaction (cs frame) is better than the j/ψ “flight” direction (hcm) as a reference for the observation of the “true” decay distribution wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ live berita debat terkini | heatherlench.com skip to content heatherlench.com live berita debat terkini the medium game pc terbaru bergenre horor feb, , informasi no comment the medium game pc terbaru bergenre horor setiap penggemar game atau yang saat ini sering dijadikan sebuah identitas khusus dengan sebutan gamer merupakan orang-orang paling bahagia karena setelah setahun dirundung covid gamer tetap bertahan dan industry game tetap berjalan lancar. hal ini dibuktikan dengan munculnya sebuah game bergenre horor yang baru saja di rilis januari lalu. game in mendapatkan reaksi yang […] read more jan, , informasi no comment hilangkan rasa bosan dengan game gratis android android merupakan salah satu jenis platform yang dapat kita gunakan untuk bermain game. di masa pandemi saat ini, bermain game menjadi salah satu kegiatan yang dapat membunuh kebosanan. game menjadi hiburan yang dapat menangkal kebosanan akibat banyaknya aktifitas yang dibatasi. dengan android, bermain game kini dapat dilakukan dengan sangat mudah. game yang kelak akan kita […] read more nov, , saran no comment tampilan debat perdana gibran dan bagyo bagaikan langit dan bumi debat perdana pada pilkada solo tahun mampu menarik perhatian dari berbagai pihak terutama para pengamat politik. bagian paling menarik perhatian adalah tampilan dari dua calon yang maju pada pilkada tahun ini yakni gibran dan bagyo. tampilan mereka sangat disorot pada debat perdana kali ini. penampilan baik gibran maupun bagyo dianggap bagaikan langit dan bumi […] read more nov, , publik no comment terkait debat perdana pilkada solo biarkan warga yang menilai berita debat politik kali ini datang dari kegiatan debat perdana untuk pilkada solo. kegiatan pilkada solo diwarnai dengan debat perdana antara kedua calon pasangan yang akan maju dalam pemilihan tersebut. pasangan yang akan mencalonkan diri sebagai wali kota dan wakil wali kota solo ini adalah gibran rakabuming raka dengan teguh prakoso yang merupakan pasangan nomor […] read more nov, , informasi no comment lokasi debat pilkada surabaya dipindahkan demi keamanan beberapa waktu ke depan indonesia akan melangsungkan acara pilkada di beberapa daerah. sebelum menggelar acara pilkada tersebut para paslon harus melangsungkan serangkaian acara pilkada. salah satu acara tersebut adalah melangsungkan acara debat pilkada. debat pilkada akan dilangsungkan secara live sehingga siapa saja bisa menyaksikannya walaupun tidak secara langsung. acara debat kali ini datang dari surabaya. […] read more posts navigation next categories debat informasi politik publik saran recent posts the medium game pc terbaru bergenre horor hilangkan rasa bosan dengan game gratis android tampilan debat perdana gibran dan bagyo bagaikan langit dan bumi terkait debat perdana pilkada solo biarkan warga yang menilai lokasi debat pilkada surabaya dipindahkan demi keamanan tags acara bersaing debat dukungan hal-hal harapan bangsa kandidat kegiatan kesimpulan live lokal maksimal masyarakat pandemi paslon pilkada politik publik team trending umum waktu warga wawancara portfolioline © heatherlench.com powered by themehunk wordpress theme clinical implications sleeping beauty jumps to new heights friedrich c. luft published online: may # springer-verlag transposons are segments of dna that can move around to different positions in the genome of a single cell [ ]. in the process, they may cause mutations and thereby increase (or decrease) the amount of dna in the genome. these mobile segments of dna are sometimes called “jumping genes”. there are two distinct types of transposons. class i transposons (retrotransposons) first transcribe the dna into rna and then use reverse transcriptase to make a dna copy of the rna to insert in a new location. class ii transposons consist only of dna that moves directly from place to place. most class ii transposons move by a “cut- and-paste” process (rather like your personal computer if you rely on the command-x and command-v function). the transposon is cut out of its location analogous to the command/control-x on a computer. the transposon is then inserted into a new location with the command/control-v maneuver. the ends of many transposons contain inverted repeats that are identical or nearly identical in sequence and read in opposite directions (fig. ); these inverted repeats are required for the transposition process. some trans- posons require a specific sequence as their target site; others can insert anywhere in the genome. the dna at the target site is cut in an offset manner similar to the “sticky ends” produced by restriction enzymes. after the transposon is inserted into the host dna, the gaps are filled in by means of watson-crick base pairing. the base pairing creates identical direct repeats flanking each end of the transposon. a specific enzyme is required for transposons to work, namely a transposase, which is encoded within some, but not all, transposons. the transposase binds to the inverted repeats at both ends of the transposon. the function and structure of some transposases (fig. ) have been worked out in detail [ , ]. sometimes transposons lose their gene for transposase. however, as long as somewhere in the cell there is a transposon that can synthesize the enzyme, their inverted repeats are recognized by the available transposase and they also can be moved to a new location. barbara mcclintock worked with maize and discovered transposons in the s [ ]. she observed that in developing somatic maize tissues, like corn kernels for example, a mutation can occur (for instance one that alters color) that can be passed on to all daughter cells. mcclintock was a cytogeneticist who learned how to stain, and thereby identify, the chromosomes of the maize plant. mcclintock was able to observe the crossing-over effect between homologous chromosomes during meiosis. she also observed the separation of the centromeres and organization of the nucleolus. she was able to irradiate the plants, she described a massive increase in the mutation rate, and she recognized the importance of the chromosom- al caps, the telomeres. her most memorable observation was the identification of a spontaneous breakpoint on chromosome of the maize plant. this breakpoint was associated with the color of various corn kernels of the plant. mcclintock termed this breakpoint “dissociator” (ds). after painstaking observations, she reached the conclusion that ds was able to change its position on the chromosome and she named ds a “jumping” gene. the world finally jumped when mcclintock was awarded the nobel prize for physiology and medicine in . ivics et al., in the laboratory group of perry hackett, identified a practicable transposon system that could be used to insert genes in a therapeutic fashion [ ]. briefly, the group found a fish gene, dormant for probably million years, which they turned into a vehicle for integrating f. c. luft (*) experimental and clinical research center, franz-volhard clinic, berlin, germany e-mail: luft@charite.de j mol med ( ) : – doi . /s - - - foreign genes into chromosomes, potentially even human chromosomes. they named this transposon system “sleeping beauty”. since then, sleeping beauty has had little rest. the international society for molecular and cell biology and biotechnology protocols and researches, named sleeping beauty the “molecule of the year ”. the designation “molecule of the year” had erstwhile been conferred by the journal science. sleeping beauty’s dna sequence had mutated in fish genomes to the point where the transposon no longer jumped, but rather slumbered as inactive ‘junk dna’. the extinct sleeping beauty jumping functions had to first be resurrected. ivics et al. [ ] used molecular phyloge- netic data to construct a synthetic sleeping beauty. this utilitarian sleeping beauty is likely equivalent to the ancient element that dispersed in fish genomes probably by horizontal transmission between species. the investigators engineered a consensus sequence of a transposase gene by eliminating the inactivating mutations. they found that the sleeping beauty transposase binds to the inverted repeats of fish transposons, and that it mediates precise, “cut-and-paste” transposition in fish, mouse, and human cells. thereby, ivics et al. [ ] produced the synthetic sleeping beauty, an active dna-transposon system from vertebrates, to perform inser- tional mutagenesis, to conduct genetic transformation, and possibly to cure genetic diseases in humans. how could these processes work and do we have evidence that they do? many agents have been used to produce mutagenesis, including radiation as employed by barbara mcclintock, chemicals such as the ethyl-nitrosourea currently en vogue, or viruses that are used to disrupt genes randomly with the hope of identifying gene functions and the associated diseases. however, finding where any given mutation oc- curred in the genome is difficult. transposable elements could help because their sequence is known, so when they mutate genes, they could provide a ‘tag’ that pinpoints their location in the genome. tagging genes by insertion is not a new idea, and geneticists working on many organisms already use transposable elements. mammals (mice) have not been of utility because known transposons are not doing much jumping in the mouse. collier et al. [ ] produced transgenic mice harboring the sleeping beauty transposon. the mouse donor dna donor dna target dna target dna transposon dna transposase transposase “jumping” gene strand transfer fig. the mechanism of “cut-and-paste” transposition is shown. first, the transposase (blue spheres) binds to specific sites at the ends of the transposon dna (red). then, transposon dna looping results in formation of a complex that brings the two ends of the transposable element close together. once the complex has been formed, the transposase cuts the transposon dna away from the flanking “donor” dna (green). after cleavage, transposase/dna complex can move about freely until it encounters and binds to the “target” dna (yellow) ..tacatgcacag.. ..atgtacgtgtc.. transposon host dna target site ..tacatgca ..atg cag.. tacgtgtc..transposon ..tacatgca ..atgtacgt transposon atgcacag.. tacgtgtc.. inverted repeats direct repeats fill in the gaps fill in the gaps indian corn fig. an inverted repeat is a sequence of nucleotides that is the reversed complement of another sequence further downstream. both ends of the transposon that consists of inverted repeats, namely identical, or nearly identical, are required for the transposon to jump. some transposons require a certain sequence as their target, while others can land anywhere in the genome. however, the transposon requires a transposase to function. shown are the colorful kernels of indian corn. barbara mcclintock explained the differences in kernel color on the basis of a somatic “jumping gene”, namely a transposon. for this idea, she was awarded the nobel prize j mol med ( ) : – line was prone to the development of cancers. these mice were mated with another mouse strain transgenic for the respective transposase. the excised transposon could then reintegrate elsewhere in the genome, sometimes close to or within a cancer-related gene. if the transposon is inserted into a gene, it would truncate the encoded protein, usually destroying its function. this action would identify genes that help to protect against cancer, like tumor-suppressor genes for example. inserting near a gene can also cause an increase in gene product. this effect would identify cancer-promoting genes (oncogenes). collier et al. [ ] reported the ability of the sleeping beauty transposon to act as a somatic insertional mutagen to identify genes involved in solid tumor formation. could sleeping beauty have therapeutic utility in terms of introducing helpful transgenes [ ]? belcher et al. [ ] tested this hypothesis as reported in this issue of j mol med. their goal was to express the heme oxygenase- (ho- ) enzyme in cells of mice with sickle cell anemia. in order to do so, they had to insert the rat hmox- gene into the recipient mice. the authors first constructed an albumin promoter- driven sleeping beauty transposase with a wild-type rat hmox- transposable element and then inserted both into a single plasmid vector. the idea behind the albumin promoter for the transposase construct was to assure ho- expression in the liver. the clones were screened and tested by restriction digest mapping and sequencing followed by protein expression in tissue culture, ho- western blot analysis, and ho- enzyme activity. the resultant clone expressed wild-type rat ho- . a nonsense control hmox- vector was then constructed by inserting four basepairs containing an early stop codon into the hmox- sequence of the sleeping beauty-wild-type-ho- plasmid. the transpo- son, which harbored the wild-type rat hmox- and the control construct were delivered by hydrodynamic tail vein injections to the mice with sickle cell anemia. eight weeks after injection, the sickle cell anemia mice had an increase in ho- activity and protein expression in liver. belcher et al. [ ] found a fivefold increase in ho- expression of the livers in their sickle cell anemia mice with resultant increased biliverdin and hemin production. probably as a result, nf-κb activation and vascular cell adhesion molecule- expression was reduced. belcher et al. [ ] speculate that ho- gene delivery to the liver is beneficial in sickle cell anemia mice by degrading pro-oxidative heme, releasing anti-inflammatory heme degradation products such as carbon monoxide and biliverdin/bilirubin into the circula- tion, activating cytoprotective pathways, and inhibiting vascu- lar stasis at sites distal to transgene expression. those claims may or may not be true. however, what concerns us here is the idea that sleeping beauty might have utility as a gene- therapy tool, an area currently residing in relative disrepute in the clinical world. however, this sad state-of-affairs could be subject to change and the current report could help. there are open questions. the somatic gene transfer in this study required only a straightforward intravenous injection of the vector plasmid and its contents. by what mechanisms did the liver cell incorporate this plasmid? no electroporation, no lipofectamine, no viruses, or other tedious methods that plague investigators (including the author) were employed. the ability of sleeping beauty to mediate stable, long-term expression in mouse tissues was initially reported by yant et al. [ ], who expressed α - antitrypsin as a reporter in normal c bl/ mice and human clotting factor ix as a therapeutic gene product in factor-ix-deficient mice. their studies also relied on injections of plasmid dna [ ]. the applicability of such a therapy is immediately obvious. the celebrated jumping frog of calaveras county is an collection of short stories by mark twain. in the story, the narrator tells about the gambler jim smiley. twain describes him as follows: “if he even seen a straddle bug start to go anywheres, he would bet you how long it would take him to get to—to wherever he going to, and if you took him up, he would foller that straddle bug to mexico but what he would find out where he was bound for and how long he was on the road.” the road for sleeping beauty is also onerous, but perhaps we should all take a bet that she can jump better than any frog. respectfully, friedrich c. luft references . voigt k, izsvák z, ivics z ( ) targeted gene insertion for molecular medicine. j mol med : – . davies dr, goryshin iy, reznikoff ws, rayment i ( ) three- dimensional structure of the tn synaptic complex transposition intermediate. science : – . richardson jm, colloms sd, finnegan dj, walkinshaw md ( ) molecular architecture of the mos paired-end complex: the structural basis of dna transposition in a eukaryote. cell : – . mcclintock b ( ) the origin and behavior of mutable loci in maize. proc natl acad sci u s a : – . ivics z, hackett pb, plasterk rh, izsvák ( ) molecular reconstruction of sleeping beauty, a tc -like transposon from fish, and its transposition in human cells. cell : – . collier ls, carlson cm, ravimohan s, dupuy aj, largaespada da ( ) cancer gene discovery in solid tumours using transposon- based somatic mutagenesis in the mouse. nature : – . ivics z, izsvák z ( ) transposons for gene therapy! curr gene ther : – . belcher jd, vineyard jv, bruzzone cm, chen c, beckman jd, nguyen j, steer cj, vercellotti gm ( ) heme oxygenase- gene delivery by sleeping beauty inhibits vascular stasis in a mural model of sickle cell disease. j mol med doi: . /s - - - (this issue) . yant sr, meuse l, chiu w, ivics z, izsvak z, kay ma ( ) somatic integration and long-term transgene expression in normal and haemo- philic mice using a dna transposon system. nat genet : – j mol med ( ) : – http://dx.doi.org/ . /s - - - sleeping beauty jumps to new heights references << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated v % \ eci\ ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /perceptual /detectblends true /detectcurves . /colorconversionstrategy /srgb /dothumbnails true /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - 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/grayimagemindownsampledepth /grayimagedownsamplethreshold . /encodegrayimages true /grayimagefilter /dctencode /autofiltergrayimages true /grayimageautofilterstrategy /jpeg /grayacsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /grayimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg grayacsimagedict << /tilewidth /tileheight /quality >> /jpeg grayimagedict << /tilewidth /tileheight /quality >> /antialiasmonoimages false /cropmonoimages true /monoimageminresolution /monoimageminresolutionpolicy /warning /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /description << /chs /cht /dan /esp /fra /ita /jpn /kor /nld (gebruik deze instellingen om adobe pdf-documenten te maken die zijn geoptimaliseerd voor weergave op een beeldscherm, e-mail en internet. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /ptb /suo /sve /enu (use these settings to create adobe pdf documents best suited for on-screen display, e-mail, and the internet. created pdf documents can be opened with acrobat and adobe reader . and later.) /deu >> /namespace [ (adobe) (common) ( . ) ] /othernamespaces [ << /asreaderspreads false /cropimagestoframes true /errorcontrol /warnandcontinue /flattenerignorespreadoverrides false /includeguidesgrids false /includenonprinting false /includeslug false /namespace [ (adobe) (indesign) ( . ) ] /omitplacedbitmaps false /omitplacedeps false /omitplacedpdf false /simulateoverprint /legacy >> << /addbleedmarks false /addcolorbars false /addcropmarks false /addpageinfo false /addregmarks false /convertcolors /converttorgb /destinationprofilename (srgb iec - 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table of content proceedings of the th international academic conference, paris front page foreword indexing publication ethics & publication malpractice statement table of content authors title pages adetiba toyin cotties massification of higher education in south africa, the good, the bad and the ugly - adipat surattana , ausawasowan alongkorn , sewiset warangkana , chotikapanich ratanawadee teacher-centered and student-centered paradigms: things teachers need to take into serious consideration - aydogan hasan , altinok emin cagatay effects of using jp -diesel fuel mixtures in a pump injector engine on engine emissions - beukes johannes andreas gerhardus th ir – implications for higher education - bozhechkova alexandra real exchange rate and competitiveness of national economy - brŮna karel credit supply constraint and external solvency: the case of the czech republic - busayanon kanrawee , laksana kittisak , ausawasowan alongkorn , mahamarn yasa problem-based learning: an efficacious way to create a beautiful and pleasant global environment - da costa vieira paulo roberto , troccoli raguenet irene , de carvalho oriol ettore , dias hugo rafael quality of teaching, corporate image and satisfaction of students enrolled in the night session of a brazilian private university: a study with structural equation modeling - davidoff yifat teaching students real world engagement skills using live simulations and reflective discussions - duczek krystian challenges for the european governments regarding the china's one belt one road initiatives in europe - dyosini thokozane princess exploring the dynamics and role that school leadership plays in the provision of professional support for novice teachers in the foundation phase - grachev vladimir , kurysheva natalia energy sources, environment and public health - grobler wynand carel johannes , dunga steve analysis of food security status among the elderly in south africa - haque nazrina does technological investment have an impact on outward foreign direct investment? a microeconometric analysis on indian manufacturing firms - harrag nassir , harrag abdelghani zrp routing protocol performance improvement using fuzzy based radius approach - helal shaimaa grammatical features and their relations to the revelation of meaning in hawthorne's the scarlet letter with special focus on the puritans' narrative sentences - herceg tomislav , vuksanoviĆ herceg iva , galetiĆ fran effects of emigration on croatian growth and pension fund sustainability prospects - hu haixia , bryson john , andres lauren internationalisation of england independent schools - jayusi wurud , bekerman zvi yes, we can! - palestinian-israeli teachers in jewish-israeli schools - konopczyŃski michaŁ open economy growth model with human capital and public debt - lai kin-sun andy impact of co-design for environment and sustainable development - lekhu motshidisi making initial teacher education meaningful: pre-service science teachers' development for effective teaching - maglakelidze ekaterine , gegeshidze eka , veshaguri maia , kamushadze natia empowering residential customers to benefit from net metering in the power market of georgia - mardanov ismatilla the determinants of economic development of greece - morake makau winnie lindi gender based violence implications on child marriage in south africa - mpanju aniceth kato the effect of microfinance services on the performance of small and medium enterprises (smes) in dar-es-salaam region, tanzania - mpanju aniceth kato international diversification impact on firm performance: a study of the east african community (eac) firms - rakthin sirisuhk , pisitsupakarn nattawat , aksaravut karuna factors influencing employee engagement in thai smes - reshef arie ethical regulation in business managers decision making - setlalentoa wendy towards enhancing reflective practice and nurturing communities of practice amongst natural sciences student teachers at a university of technology - surujlal jhalukpreya , david oladipo olalekan sport for social cohesion and development in south africa: stylized facts analysis - tamas anca cognitive reflection test - next generation - theron edwin dual commitment: evidence from an emerging country perspective - tomporoski alexandre assis , plaza tabasco julio josÉ agrarian heritage as a strategy for the development of the autonomous community of 'castilla-la mancha' (spain) and its applicability to the micro-region of canoinhas (santa catarina, brazil) - trifunovic dejan heuristic and equilibrium strategies in premium auctions - vandenberghe dÉsirÉe , albrecht johan the cost of non-communicable diseases in the european union; a future projection - zeevy-solovey orit oral presentation modeling in the efl classroom - copyright © the international institute of social and economic sciences, www.iises.net development by intercore solutions s.r.o. trollope on the sublime and beautiful | nineteenth-century literature | university of california press skip to main content close ucpress about us blog support us contact us search search input search input auto suggest search filter all content nineteenth-century literature search user tools register carnegie mellon university carnegie mellon university sign in toggle menumenu content recent content browse issues all content purchase alerts submit info for authors librarians reprints & permissions about journal editorial team contact us skip nav destination article navigation close mobile search navigation article navigation volume , issue september this article was originally published in nineteenth-century fiction previous article next article [footnotes] article navigation research article| september trollope on the sublime and beautiful susan l. humphreys susan l. humphreys search for other works by this author on: this site pubmed google scholar nineteenth-century fiction ( ) ( ): – . https://doi.org/ . / split-screen views icon views article contents figures & tables video audio supplementary data pdf linkpdf share icon share facebook twitter linkedin email guest access tools icon tools get permissions cite icon cite search site citation susan l. humphreys; trollope on the sublime and beautiful. nineteenth-century fiction september ; ( ): – . doi: https://doi.org/ . / download citation file: ris (zotero) reference manager easybib bookends mendeley papers endnote refworks bibtex toolbar search search search input search input auto suggest search filter all content nineteenth-century literature search [footnotes] [footnotes] an autobiography, the oxford trollope, (london: oxford univ. press, ), p. an autobiography percy m. thornton, harrow school and its surroundings (london: allen, ), pp. - thornton harrow school and its surroundings google scholar edward a. freeman, "anthony trollope," macmillan's magazine, jan. , p. freeman jan. macmillan's magazine n. john hall, salmagundi: byron, allegra, and the trollope family, beta phi mu chapbook, no. (pittsburgh: beta phi mu, )hall salmagundi: byron, allegra, and the trollope family google scholar n. john hall, "trollope's commonplace book, ," ncf, ( ), - . / four lectures, ed. morris l. parrish (london: constable, ), p. parrish four lectures google scholar moments of being: unpublished autobiographical writings, ed. jeanne schul- kind (sussex: the univ. press, ), p. schulkind moments of being: unpublished autobiographical writings google scholar thomas adolphus trollope, what i remember (new york: harper, ), pp. , trollope what i remember google scholar sir william gregory, an autobiography, ed. lady gregory (london: john mur- ray, ), p. gregory an autobiography google scholar thomas adolphus trollope, p. frances eleanor trollope, frances trollope: her life and literary work, vols. (london: bentley, ), i, - trollope i frances trollope: her life and literary work google scholar isabella beeton's the book of household management (london: beeton, ), p. beeton the book of household management google scholar mrs. beeton's comment on batter pudding (p. ): "it must be sent quickly to table, and covered plentifully with sifted sugar." lucullus ger nimo fernández, historia del valeroso e invencible príncipe don belianis de grecia (burgos, - )fernández historia del valeroso e invencible príncipe don belianis de grecia google scholar pope's iliad, , - robert francis damiens ( - ) jacques gaffarel ( - ) les curiositez inouyés, richmond lattimore, ed. and trans., the iliad of homer (chicago: univ. of chicago press, ), p. lattimore the iliad of homer google scholar ibid. this content is only available via pdf. copyright regents of the university of california article pdf first page preview close modal send email recipient(s) will receive an email with a link to 'trollope on the sublime and beautiful' and will not need an account to access the content. *your name: *your email address: cc: *recipient : recipient : recipient : recipient : recipient : subject: trollope on the sublime and beautiful optional message: (optional message may have a maximum of characters.) submit × citing articles via google scholar crossref latest most read most cited wasted gifts: robert louis stevenson in oceania bright sunshine, dark shadows: decadent beauty and victorian views of hawai‘i “the meaner & more usual &c.”: everybody in emma contributors to this issue recent books received email alerts article activity alert latest issue alert close modal recent content browse issues all content purchase alerts submit info for authors info for librarians about editorial team contact us online issn - print issn - copyright © stay informed sign up for enews twitter facebook instagram youtube linkedin visit the uc press blog disciplines ancient world anthropology art communication criminology & criminal justice film & media studies food & wine history music psychology religion sociology browse all disciplines courses browse all courses products books journals resources book authors booksellers instructions journal authors journal editors librarians media & journalists support us endowments membership planned giving supporters about uc press careers location press releases seasonal catalog contact us acquisitions editors customer service exam/desk requests media inquiries print-disability rights & permissions royalties uc press foundation © copyright by the regents of the university of california. all rights reserved. privacy policy accessibility close modal close modal this feature is available to subscribers only sign in or create an account close modal close modal this site uses cookies. by continuing to use our website, you are agreeing to our privacy policy. accept r current biology, vol no when a fish or a reptile changes color, it is because of the movement of tiny pigment granules in specialized skin cells called melanophores. these cells have hundreds of membrane-bound pigment granules, or melanosomes, which can be aggregated at the center of the cell or dispersed throughout the cytoplasm. when the melanosomes are aggregated the animal appears lighter, and as they disperse the animal’s skin becomes darker. the image above is of a frog melanophore in culture. the melanophore has been fixed and indirectly labelled with fluorescent antibodies against microtubules (green) — the tracks along which the pigment is moved. the melanosomes (red) have been imaged by collecting back-scattered light on a laser-scanning confocal microscope with the fluorescent filter set removed. a dna-specific dye, chromomycin a (blue), labels the nucleus. the three separate images have then been pseudocolored and combined electronically. melanophores are frequently used as a model system for the study of intracellular organelle transport and the motor proteins that power it. during pigment aggregation, melanosomes are transported along microtubules by the motor protein cytoplasmic dynein. by contrast, during pigment dispersal the melanosomes are thought to be moved along microtubules and along actin microfilaments by the kinesin- related protein kinesin-ii and by myosin-v, respectively. the movement of pigment therefore involves both the regulation of the melanosome- associated motors and the coordination of organelle transport along two separate cytoskeletal systems. for more details, see: rogers et al., proc natl acad sci usa, , : – ; rogers and gelfand, curr biol, , : – . (photograph kindly provided by stephen rogers, department of cell and structural biology, university of illinois, south goodwin avenue, urbana, illinois , usa.) biology in pictures the beauty of camouflage biology inpictures the beauty of camouflage beautiful experiments | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /s - - - corpus id: beautiful experiments @article{neumeister beautifule, title={beautiful experiments}, author={m. neumeister}, journal={hand}, year={ }, volume={ }, pages={ - } } m. neumeister published medicine hand from the acclaimed new york times science writer george johnson, an irresistible book on the ten most fascinating experiments in the history of science—moments when a curious soul posed a particularly eloquent question to nature and received a crisp, unambiguous reply. johnson takes us to those times when the world seemed filled with mysterious forces, when scientists were dazzled by light, by electricity , and by the beating of the hearts they laid bare on the dissecting table. we see galileo… expand view on sage journals.sagepub.com save to library create alert cite launch research feed share this paper tables and topics from this paper table i confusion cardiomyopathies vibration - physical agent obituary fill tourniquets singing restless legs syndrome retina muscle fibers references showing - of references sort byrelevance most influenced papers recency michael faraday : physics and faith c. russell engineering, physics save alert research feed the life and letters of faraday j. gladstone art nature pdf save alert research feed the ambiguous frog: the galvani-volta controversy on animal electricity m. pera, j. mandelbaum sociology save alert research feed a life of discovery: michael faraday, giant of the scientific revolution j. hamilton history save alert research feed matter and motion a. gray philosophy nature save alert research feed micrographia: or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon r. hooke art pdf save alert research feed never at rest. a biography of isaac newton s. schaffer medical history save alert research feed the newtonian moment: isaac newton and the making of modern culture m. feingold art save alert research feed aubrey's brief lives. w. bean medicine pdf save alert research feed the principles of psychology douglas a. spalding physics, psychology nature , pdf save alert research feed ... ... related papers abstract tables and topics references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ a guide to creating beautiful restorations product news british dental journal volume no. aug double action dental pain relief a guide to creating beautiful restorations refine your restorative skills in lovely leuven learn how to create possibly the ‘most beautiful composite restoration’ in the historic city of leuven, belgium with gc. gc g-aenial is a unique light cured composite that allows you to fabricate natural looking, aesthetic direct restorations. the hands-on g-aenial course shows you how to craft functional composite restorations; 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( ), pp. – . immanuel kant, critique of the power of judgment, tr. by paul guyer and ericmatthews (cambridge: cambridge u.p., ), § , p. , akademie edition (‘ak.’) : . references to kant not otherwise designated are to this text. kant, § , p. , ak. : ; § , p. , ak. : ; first introduction, sec. viii,ibid., p. , ak. : ; cf. sec. vii, p. , ak. : . three remarks: (i) kant alsoallows for aesthetic judgements based on displeasure (unlust), but for the sake ofsimplicity i shall consider only those based on pleasure. (ii) in § kant defines anaesthetic judgement as a one ‘whose determining ground cannot be other than subjective’ (p. , ak. : ), while in the cited passage in the first introduction, hedefines it as a judgement ‘whose predicate can never be cognition (concept of anobject)’. he apparently considers these two characterizations to be equivalent. (iii)to appear in british journal of aesthetics , vol. (january ), pp. – .kant’s beautiful roses:a response to cohen’s ‘second problem’miles rindabstract: according to kant, the singular judgement ‘this rose is beautiful’ is, ormay be, aesthetic, while the general judgement ‘roses in general are beautiful’ isnot. what, then, is the logical relation between the two judgements? i argue thatthere is none, and that one cannot allow there to be any if one agrees with kant thatthe judgement ‘this rose is beautiful’ cannot be made on the basis of testimony. theappearance of a logical relation between the two judgements can, however, beexplained in terms of what one does in making a judgement of taste. finally, idescribe an analogy between kant’s treatment of judgements of taste and j. l.austin’s treatment of explicit performative utterances, which i attribute to a deeperaffinity between their respective projects.in a recent publication in this journal, ted cohen presents three problemsin kant’s aesthetic theory, one of which, the second of the three, is particu-larly troubling, as it casts doubt on one of kant’s central claims. the pertinentclaim is the one made in the title of the opening section of the critique ofaesthetic judgement, that ‘the judgement of taste is aesthetic’. this means,among other things, that the predicate of a judgement like ‘this rose isbeautiful’, when that judgement is properly issued, is not a concept but afeeling of pleasure —the word ‘predicate’ here signifying not the verbal kant’s beautiful roses whatever exactly kant may mean by saying that the predicate of an aestheticjudgement is a feeling, it is clear that he means that it is not a concept, and that isenough for grasping the problem at hand. to my mind the best case for denying kant’s commitment to the thesis of thenon-conceptual character of judgements of taste has been made by karl ameriks.see his ‘kant and the objectivity of taste’, british journal of aesthetics , vol. ( ),pp. – ; and ‘new views on kant’s judgment of taste’, in herman parret, ed., kants Ästhetik/kant’s aesthetics (berlin and new york: walter de gruyter, ), pp.predicate of the sentence by which the judgement is expressed but thepredicative component of the corresponding mental act. on the other hand,kant allows that a judgement like ‘roses in general are beautiful’ may bederived from a collection of judgements on the beauty of individual roses. ajudgement of this second kind, however, is not ‘aesthetic’ but, in kant’sterms, ‘logical’, meaning, again among other things, that it has a concept fora predicate. it follows that the general judgement, contrary to verbalappearances, cannot have the same predicate as the singular one. but thatimplication is at odds with kant’s concession that the general judgement canbe derived from a collection of singular judgements of beauty. consequently,either judgements of beauty, whether singular or plural, always have aconcept for a predicate, or else general judgements of beauty cannot beinferred from singular ones; and neither option is compatible with kant’sdeclared views. at the end of his discussion, cohen takes up an analogy i onceadvanced between kantian judgements of taste and austinian explicitperformative utterances, but confesses himself unable to solve the problemby means of it. i do not think that the analogy will solve the problem, but ibelieve that kant can be gotten out of the present difficulty by other means.in this comment i wish to do four things: (i) to restate cohen’s problemso as to make clear its importance and its difficulty; (ii) to offer my solution;(iii) to deal with a likely objection; and (iv) to enlarge a bit upon thecomparison of kant with austin.i. the problemit is important to appreciate that the problem that cohen identifies does notarise from any casual or incidental statements that kant makes, but from oneof the defining ideas of his aesthetic theory. there is, naturally, a certainamount of learned controversy over what exactly kant means by saying thatthe judgement of taste is ‘aesthetic’, and over how deeply he is committed tothe seemingly extravagant claim that the predicate of a pure judgement oftaste is not a concept. but the conviction underlying that claim should be miles rind – . for the contrary case, see hannah ginsborg, ‘kant on the subjectivity oftaste’, ibid., pp. – . the basis of my attribution of this view to kant is contained in §§ – , pp. – , ak. : – . for a fuller account, see ginsborg, ‘kant on the subjectivityof taste’. for kant’s account of the reflective use of the cognitive powers see kant, sec.vii, pp. – , ak. : – ; also §§ , , and . this operation is the subject ofcohen’s ‘first problem’. kant, § , p. , ak. : . pluhar’s translation (indianapolis: hackett, ), which cohen uses (p. ),takes kant’s phrase ‘vergleichung vieler einzelnen’ to mean a comparison of ‘manysingular roses’. it seems to me evident from the construction of the germansentence, however, that kant means ‘many singular judgements’, as in the guyer–clear enough. technicalities aside, part of what kant means by that claim, oris trying to preserve by it, is surely the sense that declaring a thing beautifulis essentially tied to finding it beautiful, in the sense of actually being struckby its beauty, and that this is not the case with declaring a thing to be of acertain colour or origin or moral character or what have you. a description,or the testimony of others, may persuade me that a certain thing is beautiful,but i cannot legitimately express that persuasion by saying ‘x is beautiful’.rather, i must say something like ‘by all accounts, x is beautiful’; or ‘x mustbe beautiful’; or ‘x is said to be beautiful’. i cannot make an epistemicallyunqualified declaration that the thing is beautiful until i have experienced—in kant’s terms, ‘intuited’—the object for myself and thereby found pleasurein the reflective exercise of my cognitive faculties. the question whether thisjustifies kant’s claim that the predicate of a judgement of taste is not aconcept is one with which i shall deal later in this paper (section iii).given that judgements of taste are essentially tied to intuition in theway just described, it follows that they must be made on objects one at atime; or as kant says, ‘in regard to logical quantity all judgements of taste aresingular judgements.’ the point may be supported by considering whatmight seem a counterexample, a judgement to such effect as: ‘the flowers inthat vase are beautiful’. it may seem that this is a non-singular judgement oftaste. but consider: either the subject term refers to the flowers as a singlecollective object of intuition, or else the judgement as a whole means ‘eachflower in that vase is beautiful’. in the first case the judgement, thoughgrammatically plural, is logically singular, thus confirming kant’s claim. inthe second case the judgement is not one of taste at all but a judgement made,presumably, by inference from a series of judgements of taste on theindividual flowers; and this again confirms kant’s thesis. kant makes thispoint in terms of the judgement ‘roses in general are beautiful’, which hesupposes to be made by a ‘comparison of many singular ones’. if the kant’s beautiful roses matthews translation. an interesting incidental question is: what exactly does kantmean by ‘roses in general’? for the sake of simplicity i have proceeded as if hemeant ‘every rose’; but it is possible that he means something more nuanced, suchas ‘any rose that is not defective qua rose (e.g., wilted, torn, blighted, deformed,. . .)’. for the distinction between general (generale) and universal (universale)judgements, see the kant–jäsche logic, § , note . in the critique of pure reason(a /b ), the distinction is between gemeingültige and allgemeine judgements, alsocustomarily translated as ‘general’ and ‘universal’. the distinction, or someequivalent one, is, i believe, standard in scholastic logic, and even in present-daylogic, quantifiers—signs of generali ty—may be either universal or particular.inference seems too great a leap, kant could equally well have used anexample in which the generalization is across a finite number of objects of acertain kind, such as the flowers in a particular vase.indeed, kant’s point can be made without even mentioning a judge-ment of universal logical quantity. what matters is only that the judgementis general; and general judgements may be particular as well as universal. thus, if the inference from a series of singular judgements on the beauty ofindividual roses to the universal judgement ‘roses in general are beautiful’lacks credibility, take instead the unimpeachable inference from ‘this rose isbeautiful’ to ‘some rose is beautiful’. kant’s point holds good: the lattercannot be a judgement of taste, because it does not express the speaker’sfinding some object beautiful. it is made, not by an exercise of taste, but by aninference from someone’s exercise of taste (presumably one’s own).i take it to be evident, then, that, given kant’s view that a genuinejudgement of taste can only be made by the reflective exercise of one’scognitive powers upon an object of one’s own intuition, one must accept theimplication that such judgements can only be singular and not general (anda fortiori not universal). so far, there is no problem. but then we must recall kant’s claim that in logically general judge-ments of beauty, the predicate corresponding to the word ‘beautiful’ is aconcept, while in the singular judgement of taste it is not. it follows that thetwo kinds of judgement do not share a common predicate; from which inturn it follows that the general judgement, contrary to verbal appearances,cannot be a generalization of the singular one. and that seems to fly in theface of manifest fact. at the very least, it makes it difficult to explain how ageneral judgement of beauty can be inferred from a singular one, or from anycollection of singular ones. hence cohen’s observation: ‘it seems incredible,and it is more than a little frustrating, that the logic of this inference is sodifficult to formulate’ (p. ). miles rind kant, § , p. , ak. : . that is, the definitions of the beautiful as the object of a satisfaction ‘withoutany interest’ (p. , ak. : ); as ‘that which pleases universally without a concept’(p. , ak. : ); as ‘the form of purposiveness of an object, insofar as it isperceived in it without representation of an end’ (p. , ak. : ); and as ‘thatwhich is cognized without a concept as the object of a necessary satisfaction’ (p. ,ak. : ). this of course raises the issue: what is the relation between the act of judgingand the feeling of pleasure in a judgement of taste? kant poses this question in § ,and gives the surprising answer that the judging precedes the pleasure (p. , ak. : – ). commentators are divided between those who hold that there are twoacts of judging, one that gives rise to pleasure and another that requires everyoneto share that pleasure, and those who hold that there is just one act of judging,which of itself somehow constitutes the pleasure whose universal sharing itrequires. the ‘two-acts’ view is defended by paul guyer in kant and the claims of taste, nd ed. (cambridge: cambridge u.p., ), pp. – , the ‘one-act’ view byii. the solutionif there is, among the claims just presented, one to which kant is not clearlycommitted, it is surely the claim that a judgement like ‘every rose isbeautiful’ is the universal generalization of ‘this rose is beautiful’. in fact,kant never even makes that claim: he merely says that the general judgement‘arises from the comparison of many singular ones’ and ‘is no longerpronounced merely as an aesthetic judgement, but as an aestheticallygrounded logical judgement.’ the difficulty is that, if the one judgement isnot the universal generalization of the other, it is unclear what the logicalrelation between the two judgements is, or how the one may be inferred fromthe other.it seems to me that cohen, in a couple of separate remarks, actuallysuggests the way out of this difficulty, though he does not take the right pathhimself. first, he observes that, although kant says or implies that thepredicate of a general judgement of beauty is a concept, he does not say whatthis concept is (p. ). what then could it be? presumably it is the concept ofthe beautiful. but what is the content of that concept? a number of differentanswers would be compatible with the various things that kant says aboutthe content or purport of the judgement of taste (such as his four ‘definitionsof the beautiful’). i propose to adopt the formula ‘capable of being judgedwith pleasure in mere reflection’ as an analysis of the concept of thebeautiful. ‘mere reflection’ is one of kant’s descriptions of the operation ofthe cognitive faculties that gives rise to the distinctive pleasure of taste;‘judging’ is the aspect of this operation whereby the sharing of this pleasureis required of all who judge of the object. kant’s beautiful roses hannah ginsborg in ‘on the key to kant’s critique of taste’, pacific philosophical quarterly, vol. ( ), pp. – . in my view, only the ‘one-act’ interpretationis compatible with kant’s thesis that the judgement of taste is essentially tied to thejudging person’s own intuition of the object of the j udgement; but there is not spacefor me to justify this claim here. the question, please note, is how kant can maintain this; in section iii, i shalladdress the question why he maintains this, or rather why he must do so. see critique of pure reason, a /b . to be sure, kant would say that thisis only a ‘general-logical’ characterization of the act of judgement: there would alsobe a ‘transcendental-logical’ characterization in terms of the synthesis of a manifoldof empirical intuition in accordance with the transcendental unity of apperceptionand so forth. the first purports to describe how concepts are related to one anotherin the judgement, the second, how intuitions are ‘brought to concepts’ in the firstplace.this much granted, the question arises: how can kant maintain that theword ‘beautiful’ expresses that concept, or any concept, in a so-calledaesthetically grounded logical judgement, but not in a judgement of taste? the answer to this can again be derived from a remark of cohen’s. defendersof kant, cohen observes, often insist that for kant a judgement is not astatement or a proposition but an act of the mind (p. ). so what is the act inquestion? in the case of ‘every rose is beautiful’, it would be the act ofcombining the concept of a rose with the concept of beauty using what kantcalls the logical functions of the understanding, specifically those of thecategorical, universal, affirmative, assertoric form of judgement. in the caseof ‘this rose is beautiful’, the act would consist in judging the object withpleasure in mere reflection. from this it follows that, in making the judgement of taste, one does notassert that the rose in question is capable of being judged with pleasure inmere reflection; rather, one simply does so judge it. that one does so judgethe rose implies that it is capable of being so judged. that is why, once i havejudged that this rose is beautiful, i am in a position to make the logicaljudgement ‘some rose is beautiful’, or, once i have made the judgement ‘thisrose is beautiful’ of a certain number of roses, or perhaps of every rose in acertain vase, i am in a position to make the judgement ‘roses in general arebeautiful’, or ‘every rose in that vase is beautiful’. i infer the logicaljudgement from the judgements of taste that i have made, in the sense thati infer it from having made those judgements. i do not infer it from them astheir logical consequence, as i might infer ‘some man is mortal’ from ‘theman socrates is mortal’.if cohen does not see the possibility of this solution, or does not acceptit as a solution, that may be because he assumes that the items from whichan inference is made must be propositions or statements. thus, even when miles rind this is what i take cohen to be claiming in the second paragraph on p. ,though i find the exact purport of this passage difficult to make out. ‘by hypothesis’ because there is nothing about the words ‘this rose isbeautiful’ that guarantees that they are the expression of a genuine judgement oftaste: someone might utter those words, and mean them, but on the basis of thejudgements of others, say. i am aware that this implies that a judgement of taste can have nocontradictory. however, the seeming logical opposition betw een ‘x is beautiful’,uttered as a judgement of taste, and ‘x is not beautiful’ may be accounted for alongthe lines of the explanation already given: ‘x is beautiful’ betokens the performanceof a mental act whose possibility is denied by ‘x is not beautiful’. it will be notedthat this presumes that ‘x is not beautiful’ is a logical judgement, not a judgementof taste. such i believe to be the implication of kant’s declared views. i discuss therelated issue of whether ‘x is ugly’ can be a kantian pure judgement of taste (andargue that it cannot) in ‘can kant’s deduction of judgments of taste be saved?’, archiv für geschichte der philosophie, vol. ( ), pp. – , at pp. – .he takes up the idea that a kantian judgement is an act of the mind, he seemsto take this to imply that a judgement of taste should be represented in aninference by a statement to the effect that a certain person judges a certainobject with a certain sort of pleasure. but it need not, and, if i am right,should not be so represented. on the account that i have proposed, i do notdraw my inference from any premises—any statements or propositions—atall, but from my own prior acts of judging. to be sure, it is not clear how one should characterize this operationbeyond what i have already said, namely that, having made certainjudgements of taste, i am in a position to make (indeed am committed to) acertain general judgement. i call the act an inference because it is therecognition, in a judgement, of the implication of another judgement that onehas made. one may, if so minded, restrict the term ‘inference’ to the drawingof logical consequences from propositions, so long as one recognizes that inthe present case, the making of one sort of judgement has consequences forwhat other judgements one can legitimately make.what, then—to return to our troubling question—is the logical relationbetween the judgement of taste ‘this rose is beautiful’ and a generaljudgement like ‘every rose is beautiful’ or ‘some rose is beautiful’, on kant’stheory? i believe it best to say that, properly speaking, there simply is nological relation between those judgements. the first judgement being byhypothesis aesthetic, it cannot enter into any logical relation, properly socalled, with another judgement at all. making that judgement, however,does have implications for what other judgements one can legitimately make.to sum up: when i make a judgement of taste, i perform an act ofreflection whereby i both derive a certain pleasure and require that pleasure kant’s beautiful roses of everyone with respect to the object of the judgement. by doing that, i putmyself in a position to affirm the proposition that the object is capable ofbeing the object of such an act, along with whatever may be a logicalconsequence of that proposition. that is why, having made a favourablejudgement of taste on each rose in a certain vase, i may make the generaljudgement that every rose in the vase is beautiful (or that some rose isbeautiful). both judgements are brought to expression with the word‘beautiful’, but only in the second case does that word correspond to aconcept in the act of judgement itself. my logical judgement is thus, as kantsays, aesthetically grounded, but is not, despite verbal appearances, a logicalconsequence of the preceding judgement or judgements of taste. judgementsof taste have no logical consequences properly so called.iii. an objection addressedi am aware that the interpretation of kant offered here may strike somereaders as an oversubtle attempt to avoid the obvious, the obvious herebeing, supposedly, that the predicate of a judgement of taste, like thepredicate of any other judgement, surely is a concept. why not simplyembrace this fact and avoid the need for so much laborious finesse?the reply to this is that one cannot embrace that putative fact withoutrelinquishing the observation that i put forward earlier as the main supportof kant’s thesis that ‘the judgement of taste is aesthetic’. this was theobservation that, unless i have actually found a thing beautiful, in the senseof being struck by its beauty, i am in no position to affirm without qualifica-tion that it is so. i may say, on the basis of testimony or description, that thething must be beautiful, that it is said to be beautiful, that it is supposed tobe beautiful, or other things of the sort; but i cannot say outright that it isbeautiful. this could not be the case if in judgements of the form ‘x isbeautiful’, when properly made, the word ‘beautiful’ expressed a concept; forif it did so, then testimony or description could in principle yield sufficientevidence to justify a judgement of beauty apart from any exercise of taste onthe part of the judging person. the objection, however, may be pressed further. my reply, it may besaid, presumes that kant’s non-conceptuality thesis is the only possibleexplanation of why neither testimony nor description can justify anunqualified singular judgement of beauty. but an alternative explanationappears to be available, namely that an inference from testimony ordescription is subject to empirical uncertainty. to infer from a descriptionthat a certain thing is beautiful (so the explanation would run), i mustcommand some laws or reliable universal statements correlating observablefeatures of things with beauty; and unfortunately no one has yet established miles rind to deal with the other part of the proffered explanation, the part concerningjudgements from description, would require a longer discussion. to show that onepart of the explanation fails is enough to show that the explanation as a whole fails. one may be tempted to think that this is true even in kant’s theory, for onthat theory, judgements of taste are not made on the basis of anything that can becalled ‘evidence’ at all. but then it is incompetent to say that such judgements exceedthe evidence.any such statements. in order to infer from the judgements of others that athing is beautiful, i must be assured of their competence as judges and of thepropriety of their exercise of taste with respect to the particular object inquestion; and there is much room for error on both counts. thus, it seems, wecan account for our initial observation without accepting kant’s non-conceptuality claim: the reason why i cannot rely on testimony or descriptionin order to affirm without epistemic qualification that a thing is beautiful, wemay say, is not that the term ‘beautiful’ is sometimes non-conceptual, butsimply that those sources of evidence are not sufficiently reliable.but this explanation will not work. consider only the supposeduncertainty of inference from testimony. if such uncertainty were responsi-ble for the need to add epistemic qualifications to judgements of beautymade on the basis of testimony, then it would require us just as much to addsuch qualifications to judgements of beauty that we make from our ownexercise of taste; for i have just as much reason to doubt my own capacitiesand the propriety of my exercise of them as i have to doubt those of others.in that case, there would be no such thing as a legitimate judgement of taste,or a legitimate epistemically unqualified singular judgement of beauty: tocall a thing beautiful, without qualification, would always be to make anassertion in excess of the evidence. thus the explanation on offer entails therejection of the fact that was to be explained, namely that judgements of tastecan only (which also means that they can) be made on the basis of a certainacquaintance with their objects. those who would reject that claim may havetheir reasons for doing so, but they can only reject kant’s account ofjudgements of taste wholesale. in sum, one cannot modify kant’s aesthetictheory by rejecting his thesis of the non-conceptual character of judgementsof taste, but must accept or reject theory and thesis together.iv. kant an d austinfinally, i want to return to the analogy by which, as cohen reports, i oncecompared kantian judgements of taste with austinian explicit performativeutterances. the analogy was intended to have the following purport. it will kant’s beautiful roses a caution: that all utterances are performative means only that to saysomething is always to do something (beyond just saying something). it does notmean that every utterance is an explicit performative, like ‘i promise’, ‘i accept’, etc.see j. l. austin, ‘performative utterances’, in his philosophical papers, rd edn(oxford: oxford u.p., ), pp. , .be agreed (i hope) that the word ‘promise’ has the same sense in ‘i promiseto be there’ (when uttered by someone—say me—to make a promise) as in‘m. r. promised to be there’; but, according to austin, in the second case itdescribes or reports someone’s act of promising while in the first case it doesnot. thus a word may have both a descriptive and a non-descriptive functionwithout therefore having two different senses. note that the second sentenceis of a kind that can function in logical inference, while the first is not: onedraws inferences not from the sentence ‘i promise to be there’, but fromsomeone’s uttering it. these inferences nevertheless reflect genuineimplications of the utterance. with this linguistic precedent in view, it shouldbe easier to accept that the word ‘beautiful’ can have the function ofexpressing a concept in ‘some rose is beautiful’ but not in ‘this rose isbeautiful’, without thereby changing its sense; and also to accept that onedraws inferences, not from the sentence ‘this rose is beautiful’, but fromsomeone’s uttering or thinking it. in proposing this analogy, i did notsuppose that the workings of austin’s theory of explicit performativeutterances would serve to explain what is going on in the judgement of taste,nor am i inclined to follow cohen’s proposal that the word ‘beautiful’, asused in a judgement of taste, ‘[makes] explicit what act is being performedby the judge’ (p. ). the point was merely to make it easier to accept thepeculiar character that kant’s account of judgements of taste requires us toattribute to the word ‘beautiful’.there is, however, a further significance to the comparison with austin.one of the things that austin brought to the attention of anglophonephilosophers was that human utterance is subject to conditions andimplications quite distinct from those customarily called logical, but fully asirremissible, and in that sense as rigorous, as logical ones. these are theconditions and implications, not so much of the sentences that we utter, asof our acts of uttering them. austin’s aim in first setting up and thenundercutting the term ‘performative utterance’, as i understand him, is to getus first to recognize the peculiar character of such conditions and implica-tions, and then to recognize their pervasiveness: all intelligible utterancesturn out to be performative. something similar, i believe, occurs in kant’s third critique. to be sure,for kant the primary object of examination is not the utterance but thejudgement, which he seems habitually to think of, in most un-austinian miles rind see §§ – , pp. – , ak. : – . for an eloquent account of the affinitybetween kant’s account of judgements of taste and the claims of ordinary-languagephilosophy, see stanley cavell, ‘aesthetic problems of modern philosophy’, in his must we mean what we say? (cambridge: cambridge u.p., ), pp. – . seealso stanley bates and ted cohen, ‘more on what we say’, metaphilosophy, vol. ( ), pp. – , at pp. – . it may be pointed out that kant does not analogously hold that alljudgements have a ‘taste’ aspect. indeed not, but, as has been repeatedly observed,his account of judgements of taste has at least an appearance of implying that thepleasure of taste must accompany all cognitive judgements. i discuss this matter in‘can kant’s deduction of judgments of taste be saved?’ i thank ted cohen and lauren tillinghast for their comments on an earlierversion of this paper.fashion, as a kind of private mental performance. yet it is striking how muchof kant’s characterization of aesthetic judgements is in terms of how they areexpressed, and in terms of the peculiar force and burden of using such aword as ‘beautiful’, as against some other, such as ‘agreeable’. it is morestriking still that a critique of the power of judgement should find its primaryobject in a judgement marked by its non-conceptual, or in kant’s terms(which in this instance turn out to be less eccentric than they may haveseemed at first) its non-‘logical’ character. kant maintains that the judgementof taste cannot be explained in terms of what is asserted in it, but only interms of what one does in making it, namely to engage in a peculiarly ‘free’,reflective operation of the cognitive faculties. that operation is supposed toreveal the nature of our very capacity to make judgements, cognitive orother, and thus to be no less fundamental than the forms and functions oflogic. the analogue here is austin’s use of the explicit performative utteranceto reveal the performative aspect of utterance in general. i make no claimsfor the plausibility of kant’s account of the mental operation supposedlyunderlying judgements of taste. i merely draw attention to the boldness ofhis undertaking, and to its affinity with austin’s. miles rinddepartment of philosophy (ms )brandeis universitywaltham, ma usaemail: rind@brandeis.edu wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ bozkaplanşerifali turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring anadolu aĞizlarinda gÜzel adlandirma Örnekleri Şerif ali bozkaplan ∗ Özet anadolu ağızları türkçe’nin her alanında olduğu gibi güzel adlandırma alanında da pek çok malzeme sunar. güzel adlandırmanın en çok zenginlik gösterdiği alan hastalık adlarıdır. türkiye türkçesini geliştirmek, zenginleştirmek için anadolu ağızları verimli bir sahadır. anahtar kelimeler: anadolu ağızları, güzel adlandırma. in anatolian dialects beautiful naming examples abstract in all areas of the anatolian mouths turkish as many materials in the field offers good naming. called the most beautiful of the area showing the richness of disease names. the anatolian mouths is an efficient field for turkish develop, richness key words : anatolian mouths, euphemism ∗ prof. dr., dokuz eylül Üniversitesi, buca eğitim fakültesi, ortaöğretim sosyal alanlar eğitimi bölümü, türk dili ve edebiyatı eğitimi anabilim dalı anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring güzel adlandırma, kimi varlıklardan, nesnelerden söz edildiğinde doğacak korku, ürkme, iğrenme gibi duyguların, kötü izlenim ve çağrışımların önlenmesi amacına yönelen ve dünyanın her dilinde rastlanan bir değiştirme olayıdır. bu retim, her terim sözlüğünde yer almaz. mesela zeynep korkmaz’ın terim sözlüğünde yoktur. keza vecihe hatiboğlu’nunkinde de. mehmet hengirmen dilbilgisi ve dilbilim terimlerin sözlüğü’nde “anlamı ve çağrışımı korkulan, sevilmeyen, iğrenilen öğeler taşıyan sözcükler yerine, bu çağrışımları engelleyecek başkaca sözcüklerin kullanılması.” şeklinde tarif eder. verdiği örnekler arasında kanser, verem gibi hastalıklar için ince hastalık; ölmek yerine hayata gözlerini yummak vardır. david crystal da sözlüğünde euphemism için “nahoş, utanç verici ve iğrenç manalar içeren anlatımlardan vazgeçip yerine dolaylı veya müphem ifadeleri kullanmaktır” diyerek ölmek yerine geçmek, tuvalete gitmek için ise burun temizlemek örneklerini verir. anadolu ağızlarındaki güzel adlandırma örnekleri daha çok hastalık adları ile hayvan adlarında görülmektedir. başka konularda da çok ilgi çekici örneklerine rastlamak mümkündür. a. hastalıklara dair güzel adlandırmalar adı batası: köstebek de denilen çıban, kemik veremi, sıraca. ds., c. i, s. adı batasıca: . müzmin yara. . oğlanlık da denilen ateşli bir çocuk hastalığı. ds., c. i, s. adı bellisiz: verem hastalığı. ds., c. i, s. adı yaman: bir çeşit yara. ds., c. i, s. ağır engini: nezle. ds., c. i, s. ağ şiş: . Üremi. . Şeker hastalığı. ds., c. i, s. akarca: . kemik veremi. . bulaşıcı beyin hastalığı. . daima akan çıban, sıraca, fistül. . deri veremi, cüzam. . bel soğukluğu. . köstebek denilen bir hastalık. . akıntılı ve öldürücü bir hayvan hastalığı. ds., c. i, s. aksan, doğan, her yönüyle dil,tdk yay., ankara , c. iii, s. hengirmen, mehmet, dilbilgisi ve dilbilim terimleri sözlüğü, engin yayınevi, ankara , s. ags., s. crystal, david, an encyclopedic dictionary of language& languages, blackwell publishers, usa , s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring akarcacık: küçük sivilce. ds., c. i, s. ak şiş: boyunda çıkan bulaşıcı bir çeşit çıban. ds., c. i, s. ak tutma: albümin hastalığı. ds., c. i, s. al basma: loğusa kadınlarda görülen bir hastalık, loğusa humması. ds., c. i, s. al gömlek: . kızıl hastalığı. . kızamık, kızamıkçık. ds., c. i, s. al göynek: kurdeşen hastalığı. ds., c. i, s. alınmış: felçli, inme inmiş kimse. ds., c. i, s. alı fatma: Öldürücü, ateşli bir hastalık. ds., c. i, s. ateş gömleği: kızıl hastalığı. ds., c. i, s. ateş pare: bir cilt hastalığı, yılancık. ds., c. i, s. ayığ: verem. ds., c. i, s. baba: büyük ve onulmaz çıban, veba, dert, hastalık (ilenmelerde) ds., c. ii, s. bağa: boğazda deri altında olan şiş, guatr. ds., c. ii, s. bakır basma: . vücudun yer yer kızarması ile beliren bir hastalık. . dizlerden aşağıda çıkan yara. ds., c. ii, s. basma: anjin. ds., c. ii, s. basuk dilli: kekeme kimse. ds., c. ii, s. baş: Çıban, yara. ds., c. ii, s. batak: akciğer zarı iltihabı, satlıcan, zatülcenp. ds., c. ii, s. bayılma: sara hastalığı. ds., c. ii, s. bayram beyi: midesi bozulup geğirdikçe pis koku çıkaran kimse. ds., c. ii, s. bayramcalık: mide ekşimesi. ds., c. ii, s. beli gevşek: menisi çabuk gelen. ds., c. ii, s. beli kara: koyun ve keçilerde görülen, hayvanın yemeden içmeden kesilmesine sebep olan bir çeşit hastalık. ds., c. ii, s. bezgek: sıtma hastalığı. ds., c. ii, s. boğaz kıstı: anjin hastalığı. ds., c. ii, s. bozgun: Đshal. ds., c. ii, s. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring burgun: Đshal, dizanteri. ds., c. ii, s. bükmece: belden aşağıda olan feiç hastalığı. ds., c. ii, s. camra: Şirpençe de denilen bir çıban. ds., c. iii, s. cıbar: Çiçek hastalığı. ds., c. iii, s. cidirikli: dizanterili. ds., c. iii, s. cin çarpması: sara hastalığı. ds., c. iii, s. çakma: deri hastalığı, yara, çıban. ds., c. iii, s. çalgın: kötürüm, inmeli, sakat kimse. ds., c. iii, s. çarık kıkartmaz: kolera hastalığı. ds., c. iii, s. çengi yeli: romatizma hastalığı. ds., c. iii, s. engi: . felç. . bademcik iltihabı. . nezle. ds., c. v, s. eser: . sara, . delilik ds., c.v, s. eski hasır: kulunç hastalığı. ds., c.v, s. eşek gummas: kanser hastalığı. ds., c. v, s. et yaran: daha çok parmaklarda olan bir çeşit çıban, dolama. ds., c. v, s. gelincik: . verem. . yılancık hastalığı. . kalp hastalığı, . böbrek hastalığı. . lenfa düğümü. . yüzdeki çıkan çıban. . süt çocuklarında görülen öldürücü bir hastalık. . arpacık denen göz hastalığı. ds., c. vi, s. gıgı: boğazda olan şişlik, guatr. ds., c. vi, s. gızdırma: sıtma hastalığı. ds., c. vi, s. gicimik: uyuz hastalığı. ds., c. vi, s. giciyik: ekzema hastalığı. ds., c. vi, s. göğertme: kolera hastalığı. ds., c. vi, s. gök öksürük: boğmaca öksürüğü. ds., c. vi, s. gözenti: kara sevda denilen akıl hastalığı. ds., c. vi, s. gözü akık: Şaşı kimse. ds., c. vi, s. guldur: . boğaz hastalığı, guatr. . fıtık, fıtık hastalığı olan kişi. ds., c. vi, s. güzel hastalık: verem. ds., c.vi, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring haraza: ciger hastalığı, öksürük. ds., c. vii, s. haspa: tehlikeli çıban, yara. ds., c. vii, s. hıcılayık: boğmaca. ds., c. vii, s. hıra: frengi çıbanı. ds., c. vii, s. hicran: Đltihap. ds., c.vii, s. ığınık: . Đshal, dizanteri. . peklik, kabızlık. ds., c. vii, s. ığınık memesi: basur hastalığı. ds., c.vii, s. ısıtma: sıtma hastalığı. ds., c. vii, s. ıssırgı: trahoma benzer bir göz hastalığı. ds., c. vii, s. iç ağrısı: . dizanteri ya da kolera hastalığı. . verem. ds., c. vii, s. ilancık: .Çıbana benzer bir yara, yılancık. . romatizma, siyatik. . kemik veremi. ds., c. vii, s. imik boğması: boğazın iç tarafında çıkan çıban. ds., c. vii, s. ince ağrı: . verem hastalığı. . kalp hastalığı. ds., c. vii, s. issice: verem. ds., c. vii, s. it ağrısı: köpek, at, vs. hayvanlarda görülen öldürücü bir çeşit hastalık. ds., c. vii, s. it elli: felçli, çolak kimse. ds., c., vii, s. kanlı balgam: dizanteri hastalığı. ds., c. viii, s. kara çıkın: . satlıcan hastalığı, zatülcenp. . koyunlarda görülen bağırsak hastalığı. ds., c. viii, s. kara göndürme: bir çeşit çıban, şarbon hastalığı. ds., c. viii, s. karakabarcık: Şarbon hastalığı. ds., c. viii, s. kara mübarek: Şirpençe hastalığı, kan çıbanı. ds., c. viii, s. kara salgın: dizlerdeki iskorpit hastalığı. ds., c. viii, s. kara sıkmacı: bir çocuk hastalığı. ds., c. viii, s. kara taban: hayvan ve insanlarda ayak altında olan iltihaplı yara. ds.,c. viii, s. kara yatalık: tifo hastalığı. ds., c. viii, s. kaşıntı: uyuz hastalığı. ds., c. viii, s. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring kazıklama: fıtık hastalığı. ds., c. viii, s. kazıklı huma: tetanos hastalığı. ds., c. viii, s. keçe baz: davarlarda olan akciğer hastalığı. ds., c. viii, s. kedi memesi (kedi daşağı, kedi biciği): koltuk altında çıkan bir çeşit çıban, köpek memesi. ds., c. viii, s. kel hastalık: verem. ds., c. viii, s. kıl başı: . Đnsanlarda parmak üzerinde çıkan yumruk büyüklüğünde bir çeşit çıban. . koyun ve keçilerin ayaklarında çıkan bir çeşit çıban. ds., c. viii, s. kısma: menenjit hastalığı. ds., c. viii, s. kızıl avruv: kuş palazı, difteri. ds., c. viii, s. kızılca kurt: atlarda görülen öldürücü ve ateşli bir hastalık. ds., c. viii, s. kızılcık: kızamık hastalığı. ds., c. viii, s. kızıl yara: Şirpençe hastalığı. ds., c. viii, s. kızıl yel: albümin hastalığı. ds., c. viii, s. kızıl yörük: yılancık hastalığı. ds., c. viii, s. kibar hastalığı: cinsî sapıklık (erkeklerde). ds., c. viii, s. kirli paçavra: kolera hastalığı. ds., c. viii, s. konuk: bir çeşit göz hastalığı. ds., c. viii, s. köstü: yılancık hastalığı. ds., c. viii, s. kötüce: nezle. ds., c. viii, s. kötü yara: frengi hastalığı. ds., c. viii, s. kursaklı: boğazında ur olan kimse. ds., c. viii, s. kuru buru: dizanteri. ds., c. viii, s. kurudan : verem hastalığı. ds., c. viii, s. kuru gicik: uyuz hastalığı. ds., c. viii, s. kuru yel: romatizma. ds., c. viii, s. kusağ: kolera hastalığı. ds., c. viii, s. kuş kuyruğu: . büyük çıban. . difteri. ds., c. viii, s. külleme: frengi hastalığı. ds., c. viii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring hastalıklara dair güzel adlandırma örnekleri arasında adı batasıca (kemik veremi), adı bellisiz (verem), adı yaman ( yara), güzel hastalık verem), kara mübarek Şirpençe), kibar hastalığı cinsî sapıklık) ve kirli paçavra (kolera) gibi çok karakteristik örnekler göze çarpmaktadır. b. hayvan adlarına dair güzel adlandırmalar adı batasıca: . yılan. . akrep. . domuz. ds., c. i, s. adı kötü: yengeç. ds., c. i, s. adı yaman: . ayı. . domuz. ds., c. i, s. ala baba: akbaba. ds., c. i, s. ala guzu: kirpi. ds., c. i, s. alıcı: atmaca. ds., c. i, s. allâsoğen: kertenkele. ds., c. i, s. altı boğumlu: akrep. ds., c: i, s. altın baş: baykuş. ds., c. i, s. andık: . sırtlan. . domuz. ds., c. i, s. andır: akrep. ds., c. i, s. ankır hacı: eşek. ds., c. i, s. arap işi: katır. ds., c. i, s. arnavut: dev. ds., c. i, s. avanak: sıpa. ds., c. i, s. ay bagadur: maymun. ds., c. i, s. azılı: kart, erkek yaban domuzu. ds., c. i, s. bahta bakan: bukalemun. ds., c. ii, s. bayguş: baykuş. ds., c. ii, s. bici bici: bit, pire. ds., c. ii, s. biryanlı kurt: sırtlan. ds., c. ii, s. böce: sırtlan. ds., c. ii, s. burun kapan: bukalemun. ds., c. ii, s. canavar: domuz. ds., c. iii, s. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring çalağan: . kartal. . Çaylak. ds., c. iii, s. çengel kuyruk: akrep. ds., c. iii, s. ebe kulağı: salyangoz. ds., c. v, s. el öpen: kertenkele. ds., c. v, s. eli büyük: ayı. ds., c. v, s. emecen: kertenkele. ds., c. v, s. eptes bozan: tenya, şerit. ds., c. v, s. evran: buyuk yılan, canavar. ds., c. v, s. fasıl: ayı yavrusu. ds., c. v, s. gara canavar: domuz. ds., c. vi, s. gelin kadın: gelincik denen bir çeşit hayvan. ds., c. vi, s. gelin öldüren arı: büyük eşek arısı. ds., c. vi, s. goca oğlan: ayı. ds., c. vi, s. gözsüz: köstebek. ds., c. vi, s. hacı kuşu: . baykuş. . kırlangıç. ds., c. vii, s. hayırlı kuş: baykuş. ds., c. vii, s. hilhili: atmaca. ds., c. vii, s. ıfaklık: bit. ds., c. vii, s. incir kurdu: sırtlan. ds., c. vii, s. kafka küski: sırtlan. ds., c. viii, s. kaplıkurba: kaplumbağa. ds., c. viii, s. kara böcü: domuz. ds., c. viii, s. kara kaçan: sıpa, eşek yavrusu. ds., c. viii, s. kara kuş: . kartal. . Çaylak. ds., c. viii, s. karanlık kuşu: yarasa. ds., c. viii, s. kara tırnak: atmaca. ds., c. viii, s. kehten bakan: domuz. ds., c. koca kuş: kartal. ds., c. viii, s. koca oğlan: ayı. ds., c. viii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring kör bağa kuş: baykuş. ds., c. viii, s. kör kuş: baykuş. ds., c. viii, s. kötü böcü: akrep. ds., c. viii, s. kötü hayvan: domuz. ds., c. viii, s. kuyruklu: akrep. ds., c. viii, s. hayvanlara dair güzel adlandırma örnekleri ala guzu (kirpi), altın baş (baykuş), andık (sırtlan, domuz), arnavut (dev), ay bagadur (maymun), gelin kadın (gelincik), hayırlı kuş (baykuş), kara böcü (domuz), kötü hayvan (domuz) örnekleri dikkati çekmektedir. c. kadına dair düzel adlandırmalar kadına dair güzel adlandırmalar iki kısımda karşımıza çıkmaktadır. Đlki olumlu manada, ikincisi ise olumsuz manadadır. yani ilkinde kadının hamileliği, evdeki hali gibi durumları dikkate alınmışken; diğerinde kötü yola düşmesi ile ilgili özellikleri göz önüne alınmıştır. c.a. ailenin bir ferdi olarak kadın ayağı ağır(lı): yüklü kadın. ds., c. i, s. ( ) boyu güzel: görümce. ds., c. ii, s. buyurgan: kaynana. ds., c. ii, s. cici ana: Üvey anne. ds., c. iii, s. çorbacı: kadın. ds., c. iii, s. eksik etek: kadın. ds., c. v, s. ev uşağı: evin hanımı. ds., c. v, s. gan ayaklı: kadın. ds., c. vi, s. gapı kızı: hizmetçi. ds., c. vi, s. gara kütük: evin yaşlısı, büyüğü. ds., c. vi, s. gargın: gebe. ds., c. vi, s. gaşşık düşmanı: karı, eş. ds., c. vi, s. gelin ana: Üvey anne. ds., c. vi, s. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring gelin kızı: görümce. ds., c. vi, s. gocana: büyük anne. ds., c. vi, s. görme: hizmetçi kız. ds., c. vi, s. gövdeli: hamile. ds., c. vi, s. gümanlı: gebe. ds., c. vi, s. kadın ana: kaynana. ds., c. viii, s. kadıncık: görümce. ds., c. viii, s. kan ayaklı: kadın, kız, eksik etek. ds., c. viii, s. kapı kızı: besleme, hizmetçi kız. ds., c. viii, s. kaşık düşmanı: eş, kadın. ds., c. viii, s. kel kiraz: beceriksiz kız ya da kadın. ds., c. viii, s. kısa ayak: kadın. ds., c. viii, s. kızlık: Üvey kız, manevî kız. ds., c. viii, s. kül döken: kadın, eş. ds., c. viii, s. c. b. bir meta olarak kadın alaşa: kötü kadın, orospu, oynak, cilveli. ds., c. i, s. aletse: bakire olmayan kız. ds., c. i, s. artık: kızlığını gayrı meşru olarak kaybeden kız. ds., c. i, s. ayağı dışarı: fahişe, bozuk ahlaklı. ds., c. i, s. ayakçı karısı: kötü kadın. ds., c. i, s. bandırmalı: orospu, hafif meşrep kadın. ds., c. ii, s. bardel: orospu, fahişe. ds., c. ii, s. başı boş: dul kadın. ds., c. ii, s. başı dışarı: evli olup da orospuluk yapan kadın. ds., c. ii, s. baştan çıkkın: orospu. ds., c. ii, s. bazar avradı: hafif meşrep kadın, aşüfte. ds., c. ii, s. bazlamaç: kötü kadın. ds., c. ii, s. boydah: kötü kadın. ds., c. ii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring böcük: kötü kadın. ds., c. ii, s. celep: boşanmış, dul kadın. ds., c. iii, s. çapaklı: ahkaksız kadın. ds., c. iii, s. çaptırmış: sokak kadını. ds., c. iii, s. çatışmak: zina etmek. ds., c. iii, s. çatışkan: kötü kadın. ds., c. iii, s. çingir: fahişe. ds., c. iii, s. ekti: metres. ds., c. v, s. ergi: fahişe. ds., c. v, s. faşlak: kötü kadın. ds., c. v, s. fık fık: fahişe, kötü kadın. ds., c. v, s. galtak: ahlaksız kadın. ds., c. vi, s. gapatma: metres. ds., c. vi, s. gırmança: ahlaksız, kötü kadın. ds., c. vi, s. götü gara: kötü ahlaklı kadın, fahişe. ds., c. vi, s. güvende: kötü yola düşen kadın. ds., c. vi, s. kattereli: oynak kadın. ds., c. viii, s. kaynaşık: yosma, oynak kadın. ds., c. viii, s. kılbık: oynak, hafif kadın. ds., c. viii, s. kınalı: ahlaksız (kadın). ds., c. viii, s. kırıklı: Âşığı, dostu olan kadın. ds., c. viii, s. kır kızı: köylerde, kırlarda oynatılan kadın. ds., c. viii, s. köstek: yolsuz birleşmelere aracılık eden kadın. ds., c. viii, s. kadına dair güzel adlandırmaların müspet ve menfi iki yönünün olduğunu belirtmiştik. ailenin bir ferdi olarak kadın cinsine yönelik tesmiyelerden boyu güzel (görümce), cici ana (üvey anne), gövdeli (hamile), kapı kızı (hizmetçi kız)’nın yanı sıra, bir meta olarak da kadının bu anlamda meseleye konu edildiğini görüyoruz. ayağı dışarı (fahişe), bazar avradı (hafif meşrep kadın, aşüfte), böcük (kötü kadın), kınalı (ahlaksız kadın) gibi örnekler de kadının öteki yanını ifade etmektedir. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring d. mahremiyete dair güzel adlandırmalar ağzı aşa: kadının tenasül organı, ferç. ds., c. i, s. akmık: atmık, sperma. ds., c. i, s. atak: meni, döl. ds., c. i, s. avdır: erkeklik organı. ds., c. i, s. bel: meni, sperma. ds., c. ii, s. bilik: kadının cinsiyet organı. ds., c. ii, s. billûr: erkeklik bezi: ds., c. ii, s. bitik: ferç. ds., c. ii, s. bobuş: erkeğin cinsiyet organı. ds., c. ii, s. boduk: erkeklerin cinsiyet organı. ds., c. ii, s. börek: kadının cinsiyet organı. ds., c. ii, s. bülük: küçük erkek çocuklarının cinsiyet organı. ds., c. ii, s. büzdüm: kuyruk sokumu, anüs. ds., c. ii, s. büzzük: kıç, makat, anüs. ds., c. ii, s. cabul: erkeğin cinsiyet organı. ds., c. iii, s. cicik: meme. ds., c. iii, s. cüce: Çocuğun cinsiyet organı. ds., c. iii, s. çam çivisi: erkeklik organı. ds., c. iii, s. çocukluk: döl yatağı. ds., c. iii, s. emme: meme. ds., c. v, s. fıncık: cinsiyet organı. ds., c. v, s. gül: meni. ds., c. vi, s. ham ayva: yeni yetişmekte olan kızın göğsü. ds., c. vii, s. haraba: erkeğin cinsiyet organı. ds., c. vii, s. kapot: erkeklerin kullandığı, doğum önleyici naylon ya da lastik araç (prezervatif). ds., c. viii, s. kâse: dişilik organı (kız çocukları için). ds., c. viii, s. kavuk: sidik torbası. ds., c. viii, s. kıl evi: göbeğin alt kısmı, mahrem yer. ds., c. viii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring kını kınında: cinsî münasebet durumunu ifade eder. ds., c. viii, s. mahremiyete dair güzel adlandırma örnekleri hakikaten bu ayıbı giderecek cinstendir. mesela, börek (kadının cinsiyet uzvu), çam çivisi (erkeklik uzvu), gül (meni), ham ayva (yeni yetişmekte olan kız göğsü), kıl evi (mahrem yer) , vs. e. Ölüme dair güzel adlandırmalar ağaç at: tabut. ds., c. i, s. alıcı: azrail. ds., c. i, s. ansızına uğramak: birden bire ölmek. ds., c. i, s. aralık iyisi: Ölmeden önce, geçici olarak iyileşen hasta, ölüm iyisi. ds., c. i, s. avuşmak: Ölmek. ds., c. i, s. bahar: gusülhane. ds., c. ii, s. boyu batmak: Ölmek. ds., c. ii, s. can alıcı: azrail. ds., c. iii, s. cimcik yemek: Öldürmek. ds., c. iii, s. çadır: kefen. ds., c. iii, s. gara yola getmek: Ölmek. ds., c. vi, s. geçinmek: Ölmek. ds., c. vi, s. gelmezine gitmek: Ölmek. ds., c. vi, s. gider gelmez: Ölüm. ds., c. vi, s. gölertmek: Öldürmek. ds., c. vi, s. gömeç: mezar. ds., c. vi, s. gör: mezarlık, mezar. ds., c. vi, s. haşhaş: aile mezarlığı. ds., c. vii, s. hece taşı: mezar taşı. ds., c. vii, s. hıdırlık: mezarlık. ds., c. vii, s. kara babaya tutulmak: Çaresiz hastalığı tutulmak, ölmek. ds., c. viii, s. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring kara çıkın: Ölüm, kötü haber. ds., c. viii, s. kara dam: mezar. ds., c. viii, s. kara deve: Ölüm, ecel. ds., c. viii, s. kara yer: . mezar. . cehennemin dibi. ds., c. viii, s. kara yol: Ölüm. ds., c. viii, s. kel: mezar taşı. ds., c. viii, s. kıkırda(t)mak: Öl(dür)mek. ds., c. viii, s. kırmacını almak: Öldürmek, kökünü kazımak, sonunu almak. ds., c. viii, s. kuru kan: Ölü. ds., c. viii, s. Ölüm de hayatın bir parçasıdır. o, insan ömrünün son noktasıdır. dolayısıyla onsuz bir son yoktur. Öyle olunca da her hatırlandığında bile yüzümüzü buruşturduğumuz, neşemizi bozan, keyfimizi kaçıran ölüm ve etrafındaki argumanlar hakkında anadolu ağızlarındaki mesajlardan bazıları hakikaten birer deha ürünüdür: ağaç at (tabut), bahar (gusülhane), çadır (kefen), gelmezine gitmek (ölmek), hece taşı (mezar taşı), kuru kan (ölü) bunlardan bazılarıdır. f. hacete dair güzel adlandırmalar akıd: sidik. ds., c. i, s. akıdak: lazımlık. ds., c. i, s. be: büyük abdest. ds., c. ii, s. boynu buruk : Đnsan pisliği. ds., c. ii, s. çeşme: yüz numara. ds., c. iii, s. evdesthane: hela, tuvalet. ds., c. v, s. ganere: yüz numara. ds., c. vi, s. gebertü: Đnsan dışkısı. ds., c. vı, s. goduk: lazımlık, oturak. ds., c. vi, s. güllük: yüz numara. ds., c. vi, s. havrız: oturak, lazımlık. ds., c. vii, s. kenent: ayak yolu, hela. ds., c. viii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring kola: ayak yolu, hela. ds., c. viii, s. kul: ayak yolu, hela. ds., c. viii, s. kuşak çözmek: ayak yoluna gitmek, işemek. ds., c. viii, s. küllük: ayak yolu, hela. ds., c. viii, s. def-i hacete dair güzel adlandırmalar da ilgi çekicidir: boynu buruk (insan pisliği), çeşme (yüz numara), güllük (yüz numara), kola (ayak yolu), kuşak çözmek (ayak yoluna gitmek, vs. g. nesepsizliğe dair güzel adlandırmalar aralık dölü: piç. ds., c. i, s. baştarda: meşru olmayan çocuk, piç. ds., c. ii, s. bırakıntı: piç. ds., c. ii, s. bulduk: piç, bulunan çocuk. ds., c. ii, s. ekdi: . yanaşma, piç, öksüz. . yetim çocuk. ds., c. v, s. emeksiz: Üvey evlat, evlatlık. ds., c. v, s. evdik: piç. ds., c. v, s. gırık: babası belli olmayan çocuk, piç. ds., c. vi, s. göbel: piç. ds., c. vi, s. handan: babası belli olmayan, piç. ds., c. vii, s. haram: piç. ds., c. vii, s. kırık dölü: evlilik dışı ilişkiden doğan çocuk. ds., c. viii, s. kimdan: evlilik dışı doğan çocuk. ds., c. viii, s. nesepsizlik, insaniyetin tedavi edemediği yaralarından biridir. ne yazık ki sağlıklı olmayan bir neslin tohumları bu dairede de atılmaktadır. hal böyle olunca bu konu ile de alakalı bir takım güzel adlandırmalardan söz edilebilir: aralık dölü (piç), bulduk (piç), handan (babası belli olmayan, piç), kırık dölü (evlilik dışı ilişkiden doğan çocuk), kimdan ( evlilik dışı doğan çocuk), vs. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring h. kişilik Özelliklerine dair güzel adlandırmalar attırgeç: yalancı. ds., c. i, s. babıçsız: evine sadık olmayan, hovarda. ds., c. ii, s. bağrı bütün: . merhametsiz. . acıya, kedere dayanıklı, geniş yürekli. . sağlam yapılı. ds., c. ii, s. baş baş: pezevenk. ds., c. ii, s. beyni delik: akılsız, aptal. ds., c. ii, s. boğazı kara: uğursuz kimse. ds., c. ii, s. böcekçi: pezevenk. ds., c. ii, s. buçukçu: pinti. ds., c. ii, s. çelebi: homoseksüel erkek. ds., c. iii, s. çifteli: uğursuz kimse. ds., c. iii, s. çorba çöpleyen: ev işlerinde sık sık kadınların işlerine karışan erkek. ds., c. iii, s. ekti: pezevenk, yolsuz birleşmelere aracılık eden kimse. ds., c. v, s. evraksız: namussuz, şerefsiz. ds., c. v, s. fosur: homoseksüel erkek. ds., c. v, s. garaca: Đftiracı kimse. ds., c. vi, s. gara yürekli: kindar. ds., c. vi, s. gaz beyin: akılsız kimse. ds., c. vi, s. gece kirpisi: söz getirip götüren, dedikoducu. ds., c. vi, s. gidi: ahlaksız, pezevenk. ds., c. vi, s. godoş: ahlaksız adam, pezevenk. ds., c. vi, s. gotlez: puşt, ibne. ds., c. vi, s. göz bayıcı: ds., c. vi, s. gözsüz: utanmaz, arlanmaz. ds., c. vi, s. gücük: zampara, çapkın. ds., c. vi, s. gümüş göz: aç gözlü, para canlısı, cimri. ds., c. vi, s. hap hap: geveze. ds., c. vii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring havıt: boşboğaz. ds., c. vii, s. hos göt: tembel. ds., c. vii, s. hoş amatçı: dalkavuk. ds., c. vii, s. ibik: dedikoducu. ds., c. vii, s. içgili: kindar. ds., c. vii, s. içinden iğneli: hileci, sinsi. ds., c. vii, s. kapaksız: görgüsüz, terbiyesiz. ds., c. viii, s. karnı geniş: hoşgörüsü olan. ds., c. viii, s. kılbız: sinsi kimse. ds., c. viii, s. kılçıklı: belalı. ds., c. viii, s. kıldak: kadınlarla arkadaşlıktan hoşlanan, kadınsı. ds., c. viii, s. kını kırık: eski çapkın. ds., c. viii, s. kıraç yılanı: kötülüğünden kokulan kimse. ds., c. viii, s. kıyımsız: cimri. ds., c. viii, s. koca boğazlı: obur. ds., c. viii, s. kopçası kırık: geveze, ağzı gevşek, sır saklamayan. ds., c. viii, s. kopçasız: . Đradesiz. . beceriksiz. ds., c. viii, s. köçekçi: hoppa, dönek, kötü huylu. ds., c. viii, s. köpüklü: Çabuk öfkelenen, küfürler savuran, sinirli kimse. ds., c. viii, s. Đnsanı insan yapan özelliklerin başında gelir kişilik. bu özellikler belirler adeta hayattaki başarıyı. bin bir türlü özelliklerin sahibidir insanoğlu. kimi sinirlidir, kimi cimridir, kimi adam sen de cidir, kimi de… Đşte bunlar için de anadolulu güzel adlandırma yoluna baş vurmuştur: babıçsız (evine sadık olmayan, hovarda), çelebi (homoseksüel erkek), gümüş göz (aç gözlü, para canlısı), köpüklü (çabuk öfkelenen, sinirli kimse), vs. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring i. meşguliyete dair güzel adlandırmalar bacakçı: geçimini hayvan alım satımında, hayvan başına aldığı ücretle temin eden kimse. ds., c. ii, s. boz yakalı: Çiftçi, köylü. ds., c. ii, s. boş adam: hamal. ds., c. ii, s. celpci: postacı. ds., c. iii, s. çelebi: hristiyan tüccar. ds., c. iii, s. çırpıcı: hırsız. ds., c. iii, s. el bir: casus. ds., c. v, s. eli çakır: hırsız. ds., c. v, s. geçinti: dilenci. ds., c. vi, s. gizci: casus. ds., c. vi, s. göz açıcı: yan kesici, hırsız. ds., c. vi, s. kara: gece bekçisi, jandarma. ds., c. viii, s. kabakçı: vergi toplayan görevli. ds., c. viii, s. karaca: jandarma. ds., c. viii, s. karacı: . haydut. . Đftiracı, kara süren. ds., c. viii, s. kara işçi: gündelikçi, amele. ds., c. viii, s. kara kulak: . casus. . ulak, elçi. ds., c. viii, s. karamancı: hırsız. ds., c. viii, s. kellesi büyük: memur. ds., c. viii, s. kırlı: . taşralı, köylü, yabancı. . Đşçi. . testici. ds., c. viii, s. koca başı: muhtar. ds., c. viii, s. kol kıran: dolandırıcı, düzmeci. ds., c. viii, s. kol uşağı: polis, inzibat memuru. ds., c. viii, s. kökçü: . Đşçi, ırgat. . evlerde ağır işlerde çalıştırılan işçi kadın. ds., c. viii, s. kulağı tozlu: Çiftçi, işçi. ds., c. viii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring meşguliyete dair güzel adlandırma örnekleri arasında çelebi (hristiyan tüccar), eli çakır (hırsız), kara kulak (casus), kellesi büyük (memur), kulağı tozlu (çiftçi) sayılabilir. Đ. diğer güzel adlandırma Örnekleri alaca: hapishane. ds., c. i, s. allâ emri: deprem, zelzele. ds., c. i, s. asık: Çingene. ds., c. i, s. bardel hana: genelev. ds., c. ii, s. bastırık: hapishane. ds., c. ii, s. baş hapı: aspirin. ds., c. ii, s. başka: Çingene. ds., c. ii, s. bozalak: kel. ds., c. ii, s. buçuk: Çingene. ds., c. ii, s. cabar: Çingene. ds., c. iii, s. cansız at: bisiklet. ds., c. iii, s. cin arabası: bisiklet. ds., c. iii, s. çal baş: kel. ds., c. iii, s. çilli: hapishane. ds., c. iii, s. çöl etmek: uykuda yatağı ıslatmak, işemek. ds., c. iii, s. ek yok: kimsesiz, yalnız, garip. ds., c. v, s. el arabası: bisiklet. ds., c. v, s. el ayağa kavuşmak: doğurmak. ds., c. v, s. el dutamağı: rüşvet cinsinden hediye. ds., c. v, s. erişik: cin, peri. ds., c. v, s. erişikli: cin çarpmış. ds., c. v, s. eşek cenneti: ceza evi. ds., c: v, s. fadılım: Çirkin. ds., c. v, s. gacı: müslüman olmayan hacı. ds., c. vi, s. gavur elekçisi: müslüman olmayan kimse. ds., c. vi, s. anadolu ağızlarında güzel adlandırma… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring gelebik: gayrı müslümlerin ölüsü. ds., c. vi, s. gelik su: sel. ds., c. vi, s. gevik: rüşvet. ds., c. vi, s. gezergi: Çingene. ds., c. vi, s. girinti: Đç güveyi. ds., c. vi, s. göğleme: ds., c. vi, s. guru baş: Çocuğu olmayan, kısır. ds., c. vi, s. hedeme: enenmiş kimse, hadım. ds., c. vii, s. hışım: sel. ds., c. vii, s. hicaz yolu: saman yolu. ds., c. vii, s. hoş gördü: bahşiş. ds., c. vii, s. ikili: ortak, kuma. ds., c. vii, s. imam evi: kadınlara özgü cezaevi. ds., c. vii, s. kabıklı: sünnetsiz erkek. ds., c. viii, s. kapama gecesi: gerdek gecesi. ds., c. viii, s. kapçıklı: sünnet olmamış erkek. ds., c. viii, s. kapı altı: polis ve jandarma karakolu. ds., c. viii, s. kara don: Çocuğu olmayan kadın ya da erkek. ds., c. viii, s. kayran baş: kel. ds., c. viii, s. kel kız: kasırga. ds., c. viii, s. kemiklik: genelev. ds., c. viii, s. kıdım: rüşvet. ds., c. viii, s. kır: saçsız, kel. ds., c. viii, s. koca karı tarhanası: küçük dolu. ds., c. viii, s. kol canlığı: mendil. ds., c. viii, s. kolluk: karakol. ds., c. viii, s. kor ocak: Çocuksuz aile. ds., c. viii, s. kör ocak: Çocuğu olmayan aile, çocuksuz aile. ds., c. viii, s. kuzu dişi: dolu. ds., c. viii, s. Şerif ali bozkaplan turkish studies international periodical for the languages, literature and history of turkish or turkic volume / spring bu kısımdaki örnekler arasında da gayet dikkat çekici olanları vardır: alaca (hapishane), cancız at (bisiklet), el dutamağı (rüşvet), hoş gördü (bahşiş), imam evi (hapishane), kör ocak (çocuğu olmayan aile), koca karı tarhanası (küçük dolu), kuzu dişi (dolu), vs. sonuÇ anadolu ağızlarının türkçenin istikbâli için ne kadar önemli olduğunu bilmeyenimiz yoktur, sanırım. bu durumun aşağı yukarı bir asırdır farkındadır türkçe sevdalıları. o yüzden de yeri geldikçe ve gereği oldukça daima yüzlerini anadolu’ya çevirmişlerdir. Çünkü kaynak orasıdır. türkçeleştirme deseniz oradadır, türkçeyi geliştirme derseniz oradadır, türkçeyi zenginleştirme derseniz oradadır, velhasıl türkçenin hayat membaı anadolu türkçesidir. güzel adlandırmalar bakımından da durum farklı değildir. pek azımızın aklına gelebilecek deha mahsulü adlandırmalar anadolu ağızlarının esrar perdesinin ardında gizlidir. sadece viii. cilde kadar yapılan tarama çalışmalarından anlaşılmıştır ki güzel adlandırmalar yönünden de standart türkçeye anadolu’nun türkçesinin verecekleri vardır. hem de pek çok… kaynakÇa aksan, doğan, her yönüyle dil i- ii-iii cilt, tdk yay. ankara crystal, david, an encyclopedic dictionary of language&languages, blackwell publishers, usa derleme sözlüğü i-xii cilt. tdk yay. ankara - hengirmen, mehmet, dilbilgisi ve dilbilim terimler sözlüğü, engin yay. ankara foods editorial anthocyanins—nature’s bold, beautiful, and health-promoting colors taylor c. wallace , ,* and m. monica giusti department of nutrition and food studies, george mason university, fairfax, va , usa think healthy group, inc., washington, dc , usa department of food science & technology, the ohio state university, fyffe court, columbus, oh , usa; giusti. @osu.edu * correspondence: twallac @gmu.edu or taylor.wallace@me.com; tel.: + - - - received: october ; accepted: october ; published: november �� abstract: anthocyanins are among the most interesting and vigorously studied plant compounds, representing a large class of over polyphenolic pigments within the flavonoid family that exist ubiquitously in the human diet. they are “nature’s colors,” responsible for providing the beautiful red-orange to blue-violet hues present in many leaves, flowers, vegetables, and fruits, especially berries. the beginning of the st century has witnessed a renaissance in research activities on anthocyanins in several areas, mainly related to their potential health-promoting properties and their increased use as alternatives to synthetic food colors. there is increasingly convincing scientific evidence that supports both a preventative and therapeutic role of anthocyanins towards certain chronic disease states. many anthocyanin-based extracts and juice concentrates from crop and/or food processing waste have become commercially available as colorants and/or value-added food ingredients. there is a large and evolving peer-reviewed literature on how anthocyanin chemistry and concentration may affect their coloring properties in food. equally as important is the food matrix, which can have large impacts on anthocyanin color expression, stability and degradation, particularly regarding the applications of anthocyanins as food colorants and their health-promoting properties. this special edition of foods, titled “anthocyanins in foods,” presents original research that extends our understanding of these exciting and complex compounds. keywords: anthocyanin; anthocyanidin; flavonoid; cyanidin; pelargonidin; delphinidin; petunidin; peonidin; malvidin anthocyanins (greek anthos = flower and kyáneos = blue) are among the most interesting and vigorously studied plant compounds, representing a large class of over distinct anthocyanin derivatives of aglycons, known as “anthocyanidins.” in addition to their multiple phenyl groups, anthocyanins are rarely found as aglycons. the anthocyanidin typically contains ≥ sugar moiety commonly conjugated to the c hydroxyl group in the c-ring, making them glycosides. with the exception of -deoxyanthocyanins, anthocyanins exist almost exclusively in a glycosylated form; their aglycon counterparts are not stable and rarely found in nature. six anthocyanidins (cyanidin, pelargonidin, delphinidin, petunidin, peonidin, and malvidin) are prominent in nature and represent approximately % of all anthocyanins identified to date [ ] (figure a). at the primary level, the degree of hydroxylation/methoxylation of the anthocyanidin b-ring and the nature of the sugar and/or acid conjugations have the greatest effect on the color produced by these pigments. an increased number of hydroxyl and/or methoxyl groups on the b-ring of an anthocyanidin results in a bathochromic shift of the visible absorption maximum, which has a bluing effect on the color produced [ ]. substitutions on the r-groups of the b-ring may also affect the stability of the foods , , ; doi: . /foods www.mdpi.com/journal/foods http://www.mdpi.com/journal/foods http://www.mdpi.com https://orcid.org/ - - - http://dx.doi.org/ . /foods http://www.mdpi.com/journal/foods https://www.mdpi.com/ - / / / ?type=check_update&version= foods , , of pigment: hydroxylation of the b-ring has been reported to decrease the stability of the anthocyanin, while methoxylation increases the stability. acylation of the sugar substitutions and/or individual anthocyanidins may also produce a bathochromic (increased wavelength) and/or hyperchromic (increased absorption) shift, altering the spectra of a compound [ , ] (figure b). figure . anthocyanidins commonly found in nature, their b-ring conjugations, and maximum absorbance (a). bathochromic and hyperchromic shifts produced by acylation of anthocyanins (b). acylation of the anthocyanin, mainly with aromatic acids, can potentially drastically improve its stability through intermolecular/intramolecular co-pigmentation and self-association reactions, making acylated anthocyanins more desirable as food colors [ ]. anthocyanins have also been known to interact with components of the food matrix, including proteins, fat, inorganic salts, metals, and other compounds [ ]. there are extremely well-done and comprehensive reviews on the coloring properties of anthocyanins in the peer-reviewed literature [ – ]. the beginning of the st century has witnessed a renaissance in research activities on anthocyanins in several areas (figure ), mainly related to their potential health-promoting properties and their increased use as alternatives to synthetic food colors. figure . evolution of the number of papers published in pubmed over the past -years ( to ). foods , , of daily intake of anthocyanins in the u.s. diet is estimated to be . ± . mg/d, with ± % of adults ≥ years having zero intake [ ]. the relative bioavailability of anthocyanins has been recently suggested to be between – %, [ , ] as new methodologies such as c-tracer technologies have helped to identify new anthocyanin metabolites in the bloodstream and urine [ ]. there is a reasonable array of emerging epidemiological and clinical evidence that supports the notion that anthocyanins as part of a diet rich in fruits and vegetables have an important role in the prevention of several disease pathologies, most notably cardiovascular disease, type- diabetes, certain types of cancers, cognition, and vision. anthocyanins have been suggested to exert antioxidant, anti-mutagenic, anti-tumoral, anti-inflammatory, and immunomodulatory effects that are associated with maintaining homeostatic balance in the body [ ]. a recent systematic review of randomized, controlled trials found that supplementation with purified anthocyanins or anthocyanin-rich extracts improved low-density lipoprotein (ldl) cholesterol among those with hyperlipidemia or elevated biomarkers of metabolic syndrome [ ]. several extremely well-done and comprehensive reviews on the bioavailability and health-promoting properties of anthocyanins have been published in the peer-reviewed literature [ – ]. a recent review also highlights new frontiers in polyphenol (including anthocyanin) research in nutrition and health [ ]. clinical evidence indicates that polyphenols may have the potential to reduce the risk of cardiovascular disease [ ] through various mechanisms also shown to be exerted by anthocyanins and other subclasses. inverse relationships between various subclasses polyphenols and type- diabetes have also been suggested [ ]. in this special edition of foods, titled “anthocyanins in foods,” we present four original research articles that extend our knowledge of the chemistry, stability, and health-promoting properties of anthocyanins [ – ]. the special edition can be accessed here: https://www.mdpi.com/journal/foods/ special_issues/anthocyanin_color_additive. author contributions: t.c.w. and m.m.g. wrote the paper. funding: this research received no external funding. acknowledgments: the authors declare no financial compensation for the editorial. conflicts of interest: the authors declare no conflict of interest. references . wallace, t.c.; 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[crossref] [pubmed] © by the authors. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /). http://dx.doi.org/ . /jn. . http://dx.doi.org/ . /ajcn. . http://dx.doi.org/ . /j.freeradbiomed. . . http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . / . . http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /nu http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /c fo e http://dx.doi.org/ . /annurev.food. . http://dx.doi.org/ . / - . http://dx.doi.org/ . /mnfr. http://dx.doi.org/ . / . . http://dx.doi.org/ . / . . http://dx.doi.org/ . /ptr. http://dx.doi.org/ . /foods http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /foods http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /foods http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /foods http://www.ncbi.nlm.nih.gov/pubmed/ http://creativecommons.org/ http://creativecommons.org/licenses/by/ . /. references beautiful data / the democratic surround beautiful data / the democratic surround as the future approaches, equally digital and messy, it appears that there is con- siderable need for a thorough re-thinking of the postwar period which to a large extent determined the course of the current conditions. such a broadly-conceived foucauldian ‘history of the present’ attempts to shed new light on contemporary phenomena by rethinking their genealogy in the past - years. the postwar united states in particular has become a focus of debate, with specific attention paid to the macy conferences, the archaeology of the computer and of the inter- face, the legacy of emigré thinking, cybernetics, built media environments, large- scale exhibitions, the counter-culture, and the space race. to be a bit more con- crete, the history of the cold war, if read around certain tropes (multi-media, self- management, feedback, networks, organisational theory), promises to open up new perspectives on the genealogy of the computer, understood as a digital net- work operating with the conditions of constant feedback and (self-)surveillance. the two books under review here tackle different aspects of this field and provide two partly antagonistic, but mostly complementary, views of how the current state of things could be traced back into the postwar past. fred turner is an associate professor of communication studies at stanford. his work is californian in spirit, as he looks at the roots of silicon valley in the counter-culture of the s and even further back in mid- th century develop- ments. the democratic surround: multimedia and american liberalism from world war ii to the psychedelic sixties (chicago: university of chicago press, ) is a prequel of sorts to his earlier work from counterculture to cyberculture: stewart brand, the whole earth network, and the rise of digital utopianism (chicago-lon- don: the university of chicago press, ). together, the two books trace a history of information organisation and visualisation from the s until the s – if not until our very present. turner presents a clear trajectory which some critics have found to be too teleological in its direct line from bauhaus to facebook. still, his clear language and comprehensive argumentation are a re- freshing read, as he often convincingly makes surprising connections and causal- ities where others hide behind vague correspondences and associative thinking. turner focuses most strongly on visual artists’ networks such as the european emigrés (a lot of them formerly connected to the bauhaus), the circles around black mountain college, and the artistic and scientific participants of the macy conferences. thus, herbert bayer and lászlo moholy-nagy, john cage and merce vol. , no. , cunningham, margaret mead and gregory bateson emerge as central characters in the unfolding narrative. the book traces the debates about the control of large populations through mass media from the second world war into the s. underlying the concerns are ideas of how individuals’ mental dispositions are mirrored in the collective formations and mass media dispositions that govern- ments use to maintain social order. it is the united states information agency (usia), ‘the postwar governmental agency charged with overseas propaganda work’ (p. ), that turner discusses in detail. the first half is concerned with how avant-garde ideas influenced exhibitions such as road to victory and the family of man, which became blueprints for how to organise information visually and spatially. these influential shows helped to usher in a design technique which turner terms ‘democratic surround’: [t]he democratic surround was not only a way of organizing images and sounds; it was a way of thinking about organizing society. […] it was a flexible prototype, a sort of not-quite-visible image of the way the world could work that came to life at various times in words, in performances and in museum displays. (p. ) interestingly, it is no longer film and television which serve as the models for new forms of social formation and control but instead hybrid forms of exhibition de- sign, projected (moving) images, and spatial layouts. from here it is only a short step to the influential works of ray and charles eames at various world exhibi- tions, though one could also draw a line to gene youngblood’s ‘expanded cinema’ and buckminster fuller’s geodesic domes as carrying these promises into the avant-garde. the second part of the book traces these developments into the counter-cul- ture of the s. in this perspective, the events of the late s are less a break with a past than a logical continuation of a trajectory that goes back to the second world war. happenings and the new cultural formations that became visible in the mid- s are thus genealogically related to ideas of the previous decades: ‘media should be used to create environments, […] spaces could produce indivi- dual psychological changes, and […] altered audiences could ultimately change the world’ (p. ). the emergence of different forms of sociability (happening, teach-in, sit-it, be-in, psychedelics, rock concerts, festivals) simultaneously evoke ideas of a democratic personality expounded in the s and s when the us was faced with totalitarian threats from abroad, but they also point forward to the collaborative culture of networks. the democratic surround ends here and the story continues in from counterculture to cyberculture. orit halpern is currently moving from new york’s new school of social re- vol. , no. , necsus – european journal of media studies search to montréal’s concordia university, and her book distinctly displays an east coast sensibility. beautiful data: a history of vision and reason since (durham-london: duke university press, ) is less linear (and historiographic) than the democratic surround. it is structured around clouds – her book focuses on specific terms and their wide discursive networks which are historically situ- ated and contextualised. the four large chapters in turn circle key terms of the debate: archive, interface, cognition, and data organisation. as it straddles the interstices of critical science/technology studies and media studies, the first two people mentioned in the acknowledgements delineate the frame of reference: peter galison and david rodowick. the first chapter zooms in on norbert wiener, a central figure in many his- tories of media (studies), in particular on the ‘shift to forms of representation whose reference is reflexive rather than indexical’ (p. ). halpern details how concerns with storage and communication grew out of war research and devel- oped into ‘big science’ in the postwar period: ‘[i]mmersed in larger technical projects to build weapons, decode enemy tactics and messages, and later, produce multipurpose technologies for the inscription, organization, retrieval, and commu- nication of data, cybernetics contended explicitly and implicitly with older ques- tions involving mechanical reproduction and mediated communication in large networks.’ (p. ) the second chapter turns to gyorgy kepes, the eames, and kevin lynch – important figures on the borderline of design, science, and new configurations of media. all of them were pioneers in the ‘broader effort to revise concepts of knowledge and the practice of business, science, and design’ (p. ). in particular, the focus is on the newly bequeathed autonomy given to vision as a material process, and […] the reconceptualization of space as an interface. this channeling of the divide between the object and subject redefined aesthetic practice and human per- ception not in terms of surfaces, screens, or mediating bodies obscuring fanta- sized political or natural realities, but rather as conduits for communicative exchanges. (p. ) the second chapter then moves on to the restructuring of ibm on several levels: self-organisation (from hierarchy and centralisation to decentralised and flexible dynamic structures), the systems architecture that the company sells, the self- image (in advertisements, but more importantly at the new york world fair of in collaboration with the eames), as well as in the company headquarters designed by eero saarinen. the third chapter concerns models of the mind, the self, and the subject as vol. , no. , beautiful data / the democratic surround conceptualised in the work of warren mcculloch, gregory bateson, and leon festinger – who all applied information theory to the study of the human mind. feedback, interaction, and circuits took the place of stable character traits and firm structures. the second part of the chapter then turns to rational choice theory in the work of herbert simon and karl deutsch. even though halpern details these positions she keeps a critical distance to them and is able to analyse the transfor- mations of perception and cognition. at its heart, this points to our current pre- occupations: [i]t appears that many cyberneticians and social scientists embraced proximi- ties and bodily disintegrations while simultaneously hoping to achieve con- sciousness and truth through temporal displacement and feedback. this frenzy of visualization in the social sciences and design […] was coming to be embraced as the very key to democracy and ‘freedom’. this contradiction between the desire to produce knowledge and the demand to circulate infor- mation, otherwise understood as a space between older histories of knowledge and the emerging paradigm of bounded rationality, was driving a constant demand for calculation and visualization – a logic that perhaps continues to underpin our contemporary cultural attitudes to the screen, the image, and data. (p. ) the fourth and final chapter concentrates on the emerging cognitive theory. it starts by expounding on the work of george miller before turning again to the eames’ multimedia installations and the cybernetic films of john whitney sr. even though it may sound like another study of the link between the military and communication technology (in the spirit of virilio, kittler, farocki, and the birth of the internet) in this summary, halpern’s work is in effect rather an inquiry into the attendant changes of epistemology, methodology, and aesthetics. particularly interesting here is not how pure ideas were formulated but rather how they were translated into practice, as in the work of city planner kevin lynch: lynch was interested […] in studying the small differentials between represen- tational approaches to produce a more complex idea of the city. in many ways, lynch’s approach allowed greater penetration of ideas of communication, method and process than the failing efforts that were being made in the com- puter science of the time to clearly define language or thought. (p. ) halpern’s key interest though is dedicated toward the genealogy of the user, which provides the red thread connecting all the different parts: vol. , no. , necsus – european journal of media studies [t]he two decades after world war ii saw a radical reconfiguration of vision, observation, and cognition that continues to inform our contemporary ideas of interactivity and the interface. the reformulation of the observer as simulta- neously networked, decentered, and multiplied came adjoined with new notions of environment and interactivity that are the infrastructures for our contemporary models of economy, technical, and aesthetic practice. (p. ) for halpern the interface is less centered on an individual sitting in front of a screen with a designated visual set-up. instead, it refers to all kinds of interactions with ubiquitous digital networks that pervade our environment. even though there is some overlap and shared interests, both books do diverge in important aspects. halpern sees the present as one characterised by smart cities and ubiquitous computing, high concept environments and augmented reality, while turner is rather interested in the logics of the interface and social networks. consequently, their respective focus differs somewhat from the urban planning and cognitive science of halpern to the exhibition design and avant-garde net- works in turner. however, both converge in the logics of information design, in attempts to render the world we live in as simulation and model. both works include a lot of historiographical details and will remain treasure troves for future investigations into many different fields. still, we learn relatively little of complex decision-making processes within larger networks. we get many important insights into the discourses and debates, the personal overlaps and entanglements, but how western liberalism went about tackling the most pressing problems in practice still remains open to investigation. the reason might be that the respective approaches – turner focuses on networks of people, halpern on discourses – might not be expansive enough when trying to build an argument that includes governments and businesses, spontaneously-formed collectivities and small artistic communities, construction styles and big ideas. in fact, both books are possibly best read as attempts to understand how the disciplinary society became the control society, to use deleuze’s terms. turner and halpern provide fascinating and comprehensive overviews – the gaps and fissures might best be filled by micro-studies elucidating specific aspects in greater detail. thus, we need more of these histories in order to understand the futures that are open to us. with beautiful data and the democratic surround we have two powerful road maps to the immediate past that will remain important signposts for many years to come. malte hagener (philipps-university marburg) vol. , no. , beautiful data / the democratic surround microsoft word - everettian confirmation and sleeping beauty v .docx this is a preprint of a paper to appear in british journal for the philosophy of science. everettian confirmation and sleeping beauty alastair wilson university of birmingham & monash university email: a.j.wilson@bham.ac.uk abstract darren bradley has recently appealed to observation selection effects to argue that conditionalization presents no special problem for everettian quantum mechnics, and to defend the ‘halfer’ answer to the puzzle of sleeping beauty. i assess bradley’s arguments and conclude that while he is right about confirmation in everettian quantum mechanics, he is wrong about sleeping beauty. this result is doubly good news for everettians: they can endorse bayesian confirmation theory without qualification, but they are not thereby compelled to adopt the unpopular ‘halfer’ answer in sleeping beauty. these considerations suggest that objective chance is playing an important and under-appreciated role in sleeping beauty. . introduction . confirmation in eqm . sleeping beauty . the selection model . bradley’s argument . the right route to / . the breakdown of the analogy . alternative diagnoses . god’s gambling game . non-chancy sleeping beauty cases . conclusion . introduction in a recent bjps paper (bradley [ ]), darren bradley fans the flames of the debate over confirmation theory in everettian quantum mechanics (eqm). bradley argues that, by taking the centred nature of our evidence and the corresponding observation selection effects into account in the right way, everettians can tell a plausible story about how eqm gets confirmed. the spectre of automatic confirmation of many-worlds theories by any evidence whatsoever, which has worried authors like barrett, myrvold and greaves, is then dispelled without fuss; the ‘evidential problem’ for eqm is shown not to need a solution of the sort proposed by greaves [ a] and by greaves and myrvold [ ], which involves a framework of ‘quasi-credences’ and an associated update rule called ‘quasi-conditionalization’. even if quasi-credence and quasi-conditionalization might be required for us to make sense of the pre- measurement credential state of a subject who countenances eqm , such notions are unnecessary for modelling the experimental support that past measurement results provide for the theory. or so bradley argues. this discussion of centred evidence and observation selection effects in the everettian case, if correct, is significant enough by itself. but bradley follows peter lewis in drawing a close parallel between confirmation in eqm and the puzzle of sleeping beauty (sb). according to bradley, lewis is right to think that everettians have to be ‘halfers’ when it comes to sb, but he is wrong to think that this presents a problem for everettians. bradley in fact believes he can demonstrate that halfing is the right response to sb. these are highly controversial conclusions; how does bradley reach them? in brief, his claim is that in each case the strongest new evidence available to the relevant subject has the form i learned that x by a random method. given this conception of the evidence, bradley argues that eqm is not automatically confirmed and that halfing is the correct response to sb. the key thesis here is that the procedure of observation selection involved is in each problem a random one, in a sense to be explained below. in defence of this thesis, bradley offers an argument which turns on the notion of a biased observation selection procedure. in what follows i will argue that bradley is right about eqm but wrong about sb. proper attention to observation selection effects does rule out any automatic confirmation of eqm, but it does not generate the halfer position in sb. the cases are disanalogous because everettian confirmation scenarios involve no equivalent of the chancy coin toss that governs sleeping beauty’s awakenings. this is doubly good news for everettians; their theory can be confirmed by evidence in the usual way, but they need not be saddled with the unpopular halfer conclusion. in § and § i set out the details of two cases: an everettian confirmation scenario that i call ‘quantum wombat’, and the slightly modified sleeping beauty scenario that bradley calls ‘technicolor beauty’. § explains how wilson [forthcoming b] argues that they are not required even for this purpose. see lewis [ ] for details. papineau and durà-vilà [ ] reply to lewis; further epicycles are lewis [ ] and papineau and durà-vilà [ ]. i discuss this exchange in section ; my own account of this disanalogy between everettian confirmation and sleeping beauty is given in section . bradley models these cases as selections from a population, and § reconstructs his argument, which uses the selection model to support halfer-friendly and everettian-friendly conclusions. in § , i explain how i think thirders should respond. § is the core of the paper: in it i argue that the analogy between sb and confirmation in eqm breaks down in a crucial way. in § i compare my account of the disanalogy to extant accounts, and in § i describe a bizarre variably-many-worlds theory which genuinely is analogous to sb. § applies my analysis to a variant on sb which lacks the chancy element of the original case; § is a conclusion. . confirmation in eqm confirmation theory in eqm is perplexing because the theories to be compared – eqm and some candidate one-world stochastic theory st – have systematically different consequences for the number of observers in existence. consider the following case: quantum wombat: wombat is unsure whether eqm or st is correct. he has just performed a spin measurement with possible outcomes up and down, but he has not yet looked at the result. according to eqm, after the measurement there are two observers, located on branches of equal weight , one of whom observes up and the other of whom observes down. according to st, after the measurement there is one observer, who observes either up or down, with equal probability. wombat is not sure whether i) eqm is true and he is one of the two observers, or ii) st is true and he is the only observer. the metaphysics and epistemology of branch weight are controversial: see part of saunders et al. [ ] and wilson [forthcoming b] for discussion. however, for our purposes only the relatively straightforward equally-weighted case will be needed. suppose wombat observes up. should he take this observation to support eqm over st? plausibly not: the two theories are usually supposed to be (at least approximately) empirically equivalent. however, the probability that up is observed by somebody is according to eqm but is less than according to st. accordingly, the credential update rule which greaves [ a] and bradley [ ] dub ‘naïve conditionalization’ appears to break down when one of the options on the table is eqm. the following line of thought is tempting: if the many-worlds theory predicts all possible outcomes, then no possible observation can disconfirm eqm; and since no one-world theory likewise predicts all possible outcomes , every observation confirms eqm over st. in bradley’s words: the ancients could have worked out that they have overwhelming evidence for mwi merely by realizing it was a logical possibility and observing the weather. bradley [ ], p. something has gone wrong. and notice that it wasn’t any assumption that eqm was correct that landed us in this mess; it was just the assumption that eqm might be correct. compensating by setting prior credences in eqm lower is an unattractively brute-force response, since branching is so ubiquitous . we can only safely ignore the apparent problem that eqm generates for confirmation theory if we are willing to set our prior credence in eqm arbitrarily low, effectively ruling out eqm a priori. this seems an uncomfortably dogmatic position for philosophers to adopt, given how seriously physicists take eqm. . sleeping beauty confirmation in eqm is analogous in certain ways to the sleeping beauty problem, introduced to philosophers by elga [ ]. i will describe the variant that bradley calls ‘technicolour beauty’. here is the setup. i leave aside what bostrom [ ] calls ‘big-world cosmologies’: single-world theories in the traditional sense, but where a spatial or temporal infinity ensures that some plenitude of qualitative possibilities is realized. the issue of how, if at all, to quantify branching in eqm is a vexed one: see wallace [ ] and greaves [ b]. however, given that decoherence takes hold on timescales in the order of - seconds (zurek [ ] gives some accessible models), any reasonable criterion will require initial prior credence in eqm to be well below - in order to insulate us from the automatic confirmation effect. during the interval between waking and seeing the paper, technicolour beauty reproduces the original sleeping beauty scenario. accordingly, a full solution to technicolour beauty determines a solution to the original sleeping beauty scenario, while a solution to the original sleeping beauty scenario constrains (though perhaps not uniquely) a solution to technicolour beauty. from this point on i will concentrate on technicolour beauty, and will refer to it as sb for short. i hope that the consequences of my argument for the original sleeping beauty scenario are clear. technicolour beauty: beauty will be put to sleep on sunday night and a fair coin tossed. if the coin comes up heads, beauty will be woken on monday. if the coin comes up tails, beauty will be woken on monday and on tuesday. beauty’s memory of her monday experience will be erased on monday night; so each waking is initially subjectively indistinguishable from every other. however, shortly after each waking beauty will be shown either a red or a blue piece of paper. if tails comes up, she will be shown red on monday and blue on tuesday; if heads comes up, she will be shown either red or blue on monday, depending on the toss of a further fair coin. beauty knows all this. beauty sleeps. beauty wakes. beauty is shown the paper. it is red. what should her credence be that the coin landed heads, before and after seeing that the paper is red? confirmation scenarios in eqm have a structural similarity to technicolour beauty. let a spin measurement be made, which according to eqm results in an up branch and a down branch and according to st results in a stochastic transition to either up or down. then eqm predicts two branches containing up and down, just as tails predicts two days containing red and blue; st predicts one branch containing up or down, just as heads predicts one day containing red or blue. bradley provides the following table illustrating the analogy (he uses the acronym mwi to refer to eqm): bradley [ ] p. in section i will argue that the analogy between sb and confirmation in eqm breaks down; but i will pretend that it holds for the time being, while i set out bradley’s central argument. . the selection model bradley models the procedure of making an observation as the taking of a sample from a population of locations of observation. a location of observation is an agent’s having a certain perceptual experience at a particular spacetime location (and, if eqm is correct, on a particular branch). if st is correct, then when wombat observes the result of the spin measurement the population to be sampled contains one location of observation, which is either an up location or a down location. if eqm is correct, then when wombat observes the result of the spin measurement the population to be sampled contains two locations of observation, one of which is an up location and the other of which is a down location. wombat’s discovery of the result is then represented as him sampling himself from a population of two wombat- stages, one in each branch. if the coin lands heads, then the population to be sampled when beauty observes the colour of the paper contains one location of observation, which is either a red location or a blue location. if the coin lands tails, the population to be sampled when beauty observes the colour of the paper contains two locations of observation, one of which is a red location and the other of which is a blue location. beauty’s discovery of the colour is then represented as her sampling herself from a population of two person-stages, one on monday and one on tuesday. note that there is no dubious generalized indifference principle being used here: it is not assumed that each epistemic possibility must be assigned the same credence. the route to / in sleeping beauty which starts from the observation that there are three epistemically possible experiences and argues they must be equiprobable is not endorsed by any thirders i know of; and if anything, this argument is even less convincing in the case of everettian confirmation. the population from which the observations are sampled is, in both examples, a population of experiences which do in fact occur: in different branches in one case and on different days in the other. with this caveat, bradley’s sampling model looks innocuous. in sampling a single member from a population, one knows that the sample will be a member of the population, but one doesn’t know which member it will be. if one does not know which population the sample is being drawn from, this creates further uncertainty. prior to making their observations, beauty and wombat do not know which population their observation is to be drawn from, and they do not know which member will be drawn if the population contains two members. this is all there is to the sampling model, and i can’t see any grounds for disputing its applicability. why does the sampling model help? bradley’s answer is that it highlights the role of the observation selection effect produced by the nature of the observation selection procedure that selects a sample from the population. we often know not only what the sample is – what the content of our location of observation is – but also how we acquired it – how the location was picked out from the population. an observation selection procedure, or a method for short, is a particular way of drawing a sample from a population of locations of observation. bradley argues that when we make an observation of x, the total evidence we acquire is not just x occurred, and not even just i learned that x occurred, but i learned that x occurred by method m. this of course entails that x occurred, but it can entail more or less in addition. for example, if method m only selects very small objects, then learning that it has selected a very small object is less revealing about the population than it would be if method m could select an object of any size. insofar as knowledge of the method used affects the inferences that can be drawn after making a particular observation, we say that that method produces an observation selection effect. let’s apply this to our examples. on bradley’s view, the evidence that wombat gains when he sees either down or up has the form i learned that x either by st being true and x being the outcome produced by a stochastic process or by eqm being true and x being an outcome seen on one of the branches. the evidence that beauty gains when she sees either red or blue paper has the form i learned that x either by heads landing and x being seen on the one awakening, or by tails landing and x being seen on one of the two awakenings. in both cases this evidence is stronger than just x; and as bayesians, we know always to conditionalize on the strongest evidence available . not every method of sampling from a population is a random method. bradley cites eddington’s famous example of the net which can only catch fishes larger than a certain size, and adds the example of an urn of balls with an opening through which only some of the balls can fit. bradley contends that in the cases – tails and eqm – where the populations sampled contain more than one member, we should treat the samplings as random. then beauty should be equally confident that it is monday as that it is tuesday conditional on the coin landing tails, and wombat should be equally confident that he is on an up branch as that he is on a down branch conditional on eqm being correct. what is the probability of the new evidence acquired via our agents’ observations, given the various hypotheses being tested? bradley argues that in the quantum case the probability of seeing up was / , whether st or eqm is true (likewise for down); and that in the sb case the probability of seeing red was / , whether the coin landed heads or tails (likewise for blue). then in both cases the new evidence has the same probability on either hypothesis, so neither hypothesis is confirmed over the other in either case. observing the colour of the paper does not provide beauty with support for tails; and observing the result of a spin measurement does not provide wombat with support for eqm. failure to conditionalize on an agent’s strongest evidence is a failure of rationality for bayesians: it leads to fallacies of exclusion, as when someone argues from their unblemished safety record on the road to the conclusion that it would be safe to drive home, neglecting the eight pints of beer recently consumed. the claim that the probability of whatever new evidence is acquired is / on both of the hypotheses to be tested is the crux of bradley’s argument. once it is established, automatic confirmation of eqm drops out of the picture, and the argument that bradley discusses for the thirder solution lapses. so we must examine the motivation for this key claim. i’ll initially consider only the case of everettian confirmation; once i’ve ironed out some wrinkles in the argument, i’ll move to consider sb also. . bradley’s argument bradley defines a few technical terms for use in his argument. an observation selection procedure is biased towards x iff: if x is in the population, then x is selected for the sample. (he notes that this might be more aptly called ‘maximal bias’.) an observation selection procedure is random if each item in the population has an equal chance of being selected for the sample. armed with this terminology, bradley proceeds as follows. . if eqm is correct, the observation made by wombat can be modelled as a sampling from a population of two locations of observation – the up branch and the down branch. (premise.) . if eqm is correct, after the measurement wombat is only located on one branch, so he only observes a single outcome; he observes either up or down but not both. (premise.) . if the observation selection procedure which selects wombat’s observation is biased towards both up and down, then both up and down are selected and wombat observes both up and down. (from , definition of biased towards x.) . if eqm is correct, the observation selection procedure which selects wombat’s observation cannot be biased towards both up and down. (from , .) . if a selection procedure is not biased towards both of its possible outcomes, then it is random. (?) . if eqm is correct, the observation selection procedure which selects wombat’s observation is random. (from , .) . if st is correct, the observation selection procedure which selects wombat’s observation is random. (premise.) . wombat knows that either st or eqm is correct. (premise.) . the strongest new evidence acquired by an agent on making an observation is ‘i learned that x by method m’. (premise.) . the strongest new evidence ew acquired by wombat on making his observation is ‘i learned that (up or down) by a random procedure. ’ (from , , , .) . for a random procedure, the probability of any possible outcome is equal. (definition of random procedure.) . the probability of wombat’s strongest new evidence given eqm is / . (from , .) . the probability of wombat’s strongest new evidence given st is / . (from , .) . observing the result of the measurement does not confirm eqm over st. (from , .) wombat’s observation – whatever the result – does not confirm eqm over st, or vice versa. this is the intuitively correct result. there is an obvious gap in the argument as stated, and it is rather surprising that bradley fails to plug it. in an introductory section he explicitly notes that biased procedures and random procedures do not exhaust the possible types of procedure; yet he moves freely from the conclusion that the observation selection procedure which selects wombat’s observation is not biased in both directions, to the conclusion that it is random : suppose instead that there is no bias. that is, we have a random procedure - up branches have the same probability of being observed as down branches, so you are just as likely to be in an up branch as a down branch. bradley [ ], p. for all that has been established so far, the procedure which selects wombat’s observation could be biased towards up and not towards down, or be biased towards down and not towards up, or be biased towards neither outcome but be such that up is selected with probability . . (recall that ‘bias’, for bradley, means maximal bias: if x is in the population then x is definitely in the sample.) so there seems to be no good motivation for , the premise that if a selection procedure is not biased in both directions then it is random. bradley moves from lack of maximal bias in both directions (a trivial claim) to equiprobability (a highly non-trivial claim). bradley apparently intends this gap in the argument to be filled by the restricted principle of indifference proposed by elga [ ]. this principle, which bradley devotes the final section of his paper to defending, is that two centred bradley [ ] uses ‘random’ to mean not-maximally-biased. the argument given above does establish that the procedure is random in this weaker sense. but it doesn’t establish that the procedure is random in the sense specified in the quote in the main text; and it is this stronger conclusion which is needed to establish and . bradley does say that he doesn’t want to rely too much on this principle, because the thesis that the selection procedures in question are not maximally biased in either direction doesn’t require it. however, the (much stronger) thesis that the selection procedures are random does appear to require the indifference principle. worlds deserve equal credence when they correspond to the same uncentred world and the agents at the centres are ‘subjectively indistinguishable’. however, this particular indifference principle is a poisoned chalice for everettians since it conflicts with the born rule, which says that agents should apportion their credences to the branch weights. probabilities must be given by the born rule if the predictions of eqm are to agree with the predictions of conventional quantum theory; and so everettians have made sustained attempts to argue for it (see e.g. deutsch [ ], saunders [ ], wallace [ , , , ], wilson [forthcoming b]). bradley stipulates that his arguments should only be taken as applying to the case where the two branches have equal weight, thereby avoiding clashing with the born rule; but prima facie elga’s restricted principle of indifference applies to cases of unequal weight as well as to cases of equal weight. i think the best way to patch up bradley’s argument in an everettian- friendly fashion is to appeal to the symmetry of the setup. in the case of equal weight, the physical situation is exactly symmetric between the up outcome and the down outcome. there are two possible outcomes; exactly one of them will be observed by wombat; there is no fact (such as an unequal weighting of the branches) which could provide a reason why one outcome and not the other is observed by wombat; so the selection procedure by which wombat’s observation is selected must be random, on pain of arbitrariness. bradley does hint at this line of reasoning: up branches are just as hospitable to life, and just as likely to be observed as down branches. bradley [ ], p. inserting this sort of appeal to symmetry into bradley’s argument gives rise to the following modified argument, which can safely be endorsed by everettians: . if eqm is correct, the observation made by wombat can be modelled as a sampling from a population of two locations of observation – the up branch and the down branch. (premise.) . if eqm is correct, after the measurement wombat is only located on one branch, so he only observes a single outcome; he observes either up or down but not both. (premise.) . if the observation selection procedure which selects wombat’s observation is biased towards both up and down, then both up and down are selected and wombat observes both up and down. (from , definition of biased towards x.) . if eqm is correct, the observation selection procedure which selects wombat’s observation cannot be biased towards both up and down. (from , .) . if a selection procedure is not biased towards both of its possible outcomes, and it is symmetric with respect to its possible outcomes, then it is random. (premise.) . if eqm is correct, the observation selection procedure which selects wombat’s observation is symmetric with respect to its possible outcomes. (premise.) . if eqm is correct, the observation selection procedure which selects wombat’s observation is random. (from , .) . if st is correct, the observation selection procedure which selects wombat’s observation is random. (premise.) . wombat knows that either st or eqm is correct. (premise.) . the strongest new evidence acquired by an agent on making an observation is ‘i learned that x by method m’. (premise.) . the strongest new evidence ew acquired by wombat on making his observation is ‘i learned that (up or down) by a random procedure.’ (from , , , .) . for a random procedure, the probability of any possible outcome is equal. (definition of random procedure.) . the probability of wombat’s strongest new evidence given eqm is / . (from , .) . the probability of wombat’’s strongest new evidence given st is / . (from , .) . observing the result of the measurement does not confirm eqm over st. (from , .) the same argument can be applied to sb. . if the coin lands tails, the observation made by beauty can be modelled as a sampling from a population of two locations of observation: the red day and the blue day. (premise.) . if the coin lands tails, on awakening beauty is only located on one day, so she only observes a single outcome; she observes either red or blue but not both. (premise.) . if the observation selection procedure which selects beauty’s observation is biased towards both red and blue, then both red and blue are selected and beauty observes both red and blue. (from , definition of biased towards x.) . if the coin lands tails, the observation selection procedure which selects beauty’s observation cannot be biased towards both red and blue. (from , .) . if a selection procedure is not biased towards both of its possible outcomes, and it is symmetric with respect to its possible outcomes, then it is random. (premise.) . if the coin lands tails, the observation selection procedure which selects beauty’s observation is symmetric with respect to its possible outcomes. (premise) . if the coin lands tails, the observation selection procedure which selects beauty’s observation is random. (from , .) . if the coin lands heads, the observation selection procedure which selects beauty’s observation is random. (premise) . beauty knows that the coin lands either heads or tails. (premise) . the strongest new evidence acquired by an agent on making an observation is ‘i learned that x by method m’. (premise) . the strongest new evidence eb acquired by beauty on making her observation is ‘i learned that (red or blue) by a random procedure. ’ (from , , , .) . for a random procedure, the probability of any possible outcome is equal. (definition of random procedure.) . the probability of beauty’s strongest new evidence given heads is / . (from , .) . the probability of beauty’s strongest new evidence given tails is / . (from , .) . observing the colour of the paper does not confirm tails over heads. (from , .) how should thirders respond to this argument? i think they should grant the conclusion, but deny that it undermines their position. bradley’s argument is effective against someone who maintains that beauty should have an initial credence in heads of / , but who also maintains that this credence should alter to / as soon as she sees any evidence which she is not guaranteed to see (such as the red or blue paper, or cloud patterns outside her window). however, this would be an unattractive position for a thirder to adopt. sensible thirders ought to say that beauty’s initial credence on waking, before she opens her eyes and sees anything, should already be / , and that subsequent evidence should not automatically alter that credence. what bradley’s argument does achieve, in the case of sb, is to show that thirders cannot motivate their position by arguing that some new evidence that beauty acquires after awakening supports tails over heads. so bradley’s argument does undermine (bradley’s reconstruction of) the view of titelbaum [ ], which motivates the answer / via the thought that red is guaranteed to be seen if the coin lands tails. but thirders can, and should, motivate their solution differently. . the right route to / in this section i will say how i think the / answer should be motivated for the case of technicolour beauty. this solution will also entail that the / answer is correct in the original sleeping beauty scenario. the resulting position is essentially that of elga [ ], although i put a slightly different gloss on it. thirders should agree that eb is the strongest new evidence that beauty acquires on making her observation of the coloured paper. and they should agree that the probability of eb given heads is the same as the probability of eb given tails, and hence that beauty’s observation of the colour of the paper does not provide her with support for tails. but they should deny that the total evidence that beauty has after observing the colour of the paper is her evidence on sunday night plus eb. for beauty’s evidential state has undergone an additional change overnight. she has lost centred evidence, evidence about which day it is. as a result of this evidence loss, she may no longer treat the result of the coin toss as effectively chancy, in a sense to be explained below . both my claim that beauty has lost evidence and my claim that this has consequences for her credences about the outcome of the coin toss are contentious. in this section i will sketch the basis for thinking that beauty has lost evidence, and then explore the consequences of this claim for beauty’s credential state. take first the claim that beauty has lost irreducibly centred evidence overnight on monday. this evidence loss can be most straightforwardly expressed by saying that she has lost evidence about which day it is now; it cannot be expressed in any fragment of language which does not contain indexical terms. before going to sleep beauty knew what day it was then – it was sunday. on awakening she does not know which day it is now – it could be monday or tuesday. normally, as the days pass without our losing track of their passing, we lose some centred evidence but gain corresponding new centred evidence. in cases like sleeping beauty, or like the case of o’leary described by elga [ ], there is a loss of irreducibly centred evidence which is not adequately compensated for. see dieks [ ] for further discussion of this point. of course, to point to a way in which beauty’s evidential state changes overnight is not yet to show that she should have credence / in heads on waking. the change in evidential state might simply be irrelevant, or it might be relevant in a way which results in a credence other than / in heads. this brings us to the second claim; that the overnight change in evidential state means that beauty should no longer regard the coin toss as effectively chancy. to explain what i mean by this, it will help to start by rehearsing one of the arguments given in elga [ ] for the answer / . see p. for the precise definition of this term. at the heart of this argument are three assumptions . the first assumption is that chance is the norm of credence: that in a situation where an agent knows the chances and has no inadmissible information , the agent’s credences should match the chances. where a fair coin toss is in the future, an agent cannot have inadmissible information about it without the help of precognition or some other form of backwards causation. the second assumption is that it doesn’t matter when the coin is tossed, as long as it has been tossed by tuesday morning. in the original version of sb, the coin is tossed on sunday night. but since beauty will be woken on monday regardless, and the procedural need for the information about the result of the coin does not arise until the experimenters are deciding whether to wake beauty on tuesday morning, the coin could equally well be tossed on monday night. beauty knows this, so she ought to adopt the same credence on waking if she knows the coin is tossed on monday as she adopts if she knows the coin is tossed on sunday. (indeed, it should make no difference to her credences if the coin is tossed even earlier, say on saturday night.) the third assumption, which elga motivates via his restricted principle of indifference, is that the probability of it being monday conditional on tails is the same as the probability of it being tuesday conditional on tails. whatever we may think about the restricted principle of indifference in general (and i have suggested above that it would be a mistake for everettians to adopt it unrestrictedly), this particular application of it seems unproblematic. beauty cannot distinguish between a monday waking given tails, and a tuesday waking given tails. she thus has no reason to assign them different credences, and so her credence that it is monday conditional on tails should be the same as her credence that it is tuesday conditional on tails. together, these assumptions entail that the thirder solution is correct. in the case in which the coin is tossed on monday night, the chance on monday of the coin landing heads is / . beauty knows this, so (by the first assumption) on awakening her credence in the coin landing heads conditional on it being monday is / . on awakening, beauty does not know whether a) it is monday (in which case the toss is in the future, and the chance of heads and of tails are both / ) or b) it is tuesday (in which case the toss has already occurred, and the chance of heads is and the chance of tails is ). one further assumption, denied inter alia by lewis [ ], is that on awakening beauty’s credence that the coin lands heads cannot come apart from her credence that this is a heads-waking. the motivation for this assumption ought to be clear: the setup of the case ensures that on awakening beauty knows that these two propositions have the same truth-value, so she should assign them equal credence. see lewis [ ] and hoefer [ ] for classic discussions of the notion of inadmissible information. using a standard notion for subjective credence: cr(heads|monday) = / , by the principal principle. cr(heads|tuesday) = , since beauty is awakened on tuesday only if the coin lands tails. so if cr(tuesday) > , then cr(heads) < / . this is already enough to establish the falsity of the halfer conclusion. by the third assumption and an application of bayes’ rule, the thirder conclusion follows. the above argument applied to the case in which the coin is tossed on monday night. but by the second assumption, the thirder conclusion is correct for the case where the coin is tossed on monday night if and only if it is correct for the case where the coin is tossed on sunday night. so the thirder conclusion follows for these cases also. on awakening, beauty’s uncentred evidence does not change, but her centred evidence does change: elga’s argument shows how this change results in a shift in credence in heads from / to / . the remaining difficulty is that of explaining why this evidential change should produce such a credential shift. after all, we are constantly undergoing changes in centred evidence which have no significant effect on our credences in uncentred propositions. i suggest that the difference is that in sb the overnight loss of centred evidence is hooked up to a chancy memory-loss process. this means that different inferences can be drawn from the available self-locating evidence before and after going to sleep on sunday. to explain this, i think we can usefully appeal to the notion of a proposition’s being effectively chancy. on sunday night, it is effectively chancy for beauty whether heads; on awakening, it is no longer effectively chancy whether heads. effective chanciness isn’t the same as chanciness in the sense of lewis [ ], according to which all past propositions have chance zero and the chance of a proposition cannot vary from person to person. for a proposition to be effectively chancy is both a person-dependent and a time-dependent matter. the same proposition can be effectively chancy for one person and not for another (as when the latter but not the former has observed the result of a coin toss), and it can be effectively chancy for a given person at one time and another (before and arntzenius [ ] resists this argument on the grounds that beauty knows she may suffer a ‘cognitive mishap’ on monday night, and hence that she will not necessarily remain an ideal bayesian agent. but it is unclear why this means that she should not do the best she can, by conditionalizing on her strongest evidence whenever possible. arntzenius also objects that the argument hooks up beauty’s credence in heads to the issue of whether she accepts causal or evidential decision theory. i do not find this connection either surprising or worrisome. (nor does briggs [ ].) after observing the result of the coin toss, respectively). as i use the phrase, for a proposition p to be effectively chancy for agent a at time t is for p to be or have been chancy, and for a to possess no evidence at t which is or might be inadmissible with respect to a. since effective chanciness is an agent-dependent and time-dependent business, evidence that some proposition is effectively chancy is irreducibly- centred evidence. it is evidence that the proposition is effectively chancy now, for me. such evidence will not be treatable in a framework where all evidence takes the form of untensed propositions with timeless truth-values. this is no great surprise: in response to sb, several authors have attempted to develop more general accounts of credential updating which can cope adequately with centred evidence. such accounts can be found in titelbaum [ ], meacham [ ], bradley [ ], schulz [ ] and schwarz [ ]. i assume that if a proposition p is effectively chancy for a at t, then at t a is bound indirectly by the principal principle with respect to t. even though p may no longer be chancy at t, if p was chancy at some earlier time and if a both knows the chance that p had and has no evidence inadmissible with respect to p, then at t a is still bound to match her credence to the value that the chance of p is known to have had. the notion of effective chanciness gives us the resources to say what sort of change in beauty’s evidence occurs overnight on sunday. where on sunday night the result of the coin toss is effectively chancy for beauty, when she awakes on monday it is no longer effectively chancy. for all she knows on awakening, it could now be tuesday, in which case the coin would have to have already been tossed and landed tails. in that case, beauty’s new centered evidence on awaking is inadmissible with respect to the coin toss. so beauty has lost evidence that the result of the coin toss is an effectively chancy matter, because she has lost evidence that she has no inadmissible evidence. as a result, she is no longer constrained by the principal principle to match her credences to the objective chances. since the only scenario in which beauty possesses any inadmissible evidence is a scenario in which the coin landed tails and it is tuesday, learning that the coin toss is no longer effectively chancy should alter her credences in the direction of tails. by the second assumption of the argument given above and an application of bayes’ rule, she should end up with credence / in heads. armed with this result, we can consider what would happen if beauty learns that it is monday. when she does, she learns that she has no evidence that is inadmissible with respect to the coin toss. she thereby re-acquires the evidence she lost overnight: that the coin toss is effectively chancy. accordingly, she is once again bound by the principal principle with respect to the chance of heads, and must adopt credence / in heads. although this line of thought has been developed in the context of technicolour beauty, it is essentially the same as elga’s solution to the original sleeping beauty case. one way out for halfers is to maintain that it really matters whether the toss is past or future. halfers are committed to the idea that if beauty learns that it is monday, she should increase her credence to / that the coin will land heads. since it is crazy to think of a future fair coin toss that it is / likely to land heads , halfers must say there is a difference between the toss-on-sunday and toss-on-monday cases. the resulting view has it that in a case in which beauty knows the coin is tossed sunday night, halfing is the correct solution; but that in a case in which beauty knows the coin is tossed monday night, thirding is the correct solution. this requires beauty to bet differently depending on whether a coin toss is future or past, even when she knows that the toss is fair . i will not investigate here how halfers might seek to sweeten this pill. in this section i have shown how thirders can motivate their position while simultaneously accepting bradley’s conclusions about the nature of the new evidence beauty acquires on seeing the coloured paper, and about the bearing of this evidence on the result of the coin. the next section argues that the analogous move fails in the case of automatic confirmation in eqm. the analogy between sleeping beauty and quantum wombat breaks down, since there is no chanciness in the latter case to correspond to the chanciness of the coin toss. . the breakdown of the analogy beauty loses relevant centred evidence, and therefore should not continue to treat the result of the coin toss as effectively chancy. however, wombat loses no similarly-relevant centred evidence. wombat does not know, in advance of performing the spin measurement, that whether st or eqm is true will be fixed by the result of a future fair coin. indeed, wombat knows that this is not the case – whichever theory is true is already true, and has chance . as a result, it is not the case that whether st or eqm is true ceases to be an effectively chancy matter on performing the spin measurement, and wombat’s credences in st and eqm should not change. eqm is not automatically confirmed. crazy or not, this was the view defended by lewis [ ]. according to lewis, on discovering that it is monday beauty acquires knowledge which is inadmissible with respect to a future coin toss. given that sb involves no precognition or any other variety of backwards causation, this suggestion is implausible. what if the time of the toss itself is unknown: for example, if it will occur during the first minutes of the monday waking? what if it is unknown in a self-centred way: if it will occur minutes after the monday waking, and there is no clock in beauty’s room? i leave these awkward questions to halfers. the disanalogy between sb and qw is, on reflection, a straightforward one. whether eqm or st is true does not depend on any chance process, and wombat knows that. in contrast, whether the coin lands heads or tails does depend on a chance process, and beauty knows that. consequently beauty loses relevant evidence when she is put to sleep, but wombat loses no relevant evidence on performing the measurement. the effect which generates the answer / in the case of sleeping beauty is absent in the case of everettian confirmation scenarios. wombat is correct to think that the probability of whichever experimental result he sees given st is the same as the probability of his new centred evidence given eqm. and beauty is correct to think that the probability of whichever colour of paper she sees is the same given heads as it is given tails. but wombat can, after the measurement, still take into account all the evidence he had before the measurement that was relevant to eqm vs. st. beauty cannot, after awakening, still take into account all the evidence she had before going to sleep that was relevant to heads vs. tails. for some of that was irreducibly centred evidence: that the result of the coin toss was effectively chancy. bradley at one point implies that wombat does lose information, endorsing lewis’ evocative phrase ‘gets lost in the branches’ (bradley [ ] p. ). the idea seems to be that before the spin measurement, wombat knows exactly where he is – on the initial branch, about to press the button, while afterwards he could be in either of two places: the problem with this response is that the information loss in question is irrelevant. it doesn’t provide evidence which bears on whether a particular proposition is currently effectively chancy, so it does not give rise to any thirder- style shift in credence. the irrelevance of the self-locating uncertainty which lewis and bradley point to is underlined by considering the diverging interpretation of eqm, defended by saunders [ ] and by wilson [forthcoming a]. according to overlapping eqm, different branches have earlier segments in common: the ‘splitting worlds’ metaphor is apt. according to diverging eqm, different branches are mereologically isolated: the ‘parallel worlds’ metaphor is apt. diverging worlds may match one another up to a time, but they have no segments in common. wombat, pre-measurement, is on one branch and one branch only, although he has no idea whether it is a branch on which up will be measured or a branch on which down will be measured. he is just as lost in the branches as he is after the measurement. pictorially: the evidence which defenders of the analogy must suppose that wombat loses is evidence which, on the diverging picture, wombat never even had. but the choice between branching and diverging versions of eqm, even if it is relevant to pre-measurement uncertainty , should not be relevant to the bearing of past observations on the likelihood of a many-worlds theory. it is a problem with the analogy that it says that the choice between branching and divergence is relevant in this way: the analogy entangles issues of metaphysics and epistemology which are better kept apart. i have argued that the source of the disanalogy between confirmation of eqm and technicolour beauty is that whether heads or tails is true is determined by a chance process, while whether eqm or st is true is not so determined. in the next section i compare this suggestion to some alternative accounts of the disanalogy. wilson [forthcoming a] argues that it is. . alternative diagnoses other authors to diagnose disanalogies between everettian confirmation and sb are papineau & durà-vilà [ a, b] and peterson [ ]. as far as i can see, these authors give competing accounts of the disanalogy, both of which differ from my own account. the issue is complicated because these authors primarily discuss the ‘simplified sleeping beauty’ case presented in lewis [ ], which involves no coin toss but rather has beauty awaken on both monday and tuesday, with her memory erased in between. the simplified sleeping beauty case is not analogous to everettian confirmation scenarios, but is supposed to be analogous to branching events for agents who are certain of the truth of eqm. papineau & durà-vilà take the difference between the simplified sb case and the case of everettian branching to be that there are ‘two branches of reality after the spin measurement’, while there is ‘only one branch of reality in the simplified sleeping beauty case’. they claim that this allows everettians to rationally assign credences of less than to each outcome of the spin measurement, while beauty in the simplified scenario must assign credence to waking on both monday and tuesday. however, this claim appears to rest on a conflation of the probability that someone wakes on monday with the probability that it is now monday for a just-awakened agent. papineau and durà-vilà correctly claim that the probabilities that someone wakes on monday and that someone wakes on tuesday are both in the simplified sleeping beauty case. but likewise, the probabilities that someone sees up and that someone sees down are both in the case of everettian branching. papineau & durà-vilà have not explained why the difference between days and branches leads to a difference between everettian branching and the simplified sleeping beauty scenario. once we resist the conflation of the hypotheses that it is now monday and that someone is awake on monday, then (as lewis [ ] replies) it is altogether unclear why the metaphysical difference between days and branches to which papineau and durà-vilà point is a relevant difference. after the measurement but before the results have been examined, wombat knows that – if eqm is correct - he is one of two observers, but does not know which. likewise, after awakening beauty knows that – if the coin landed tails – she is on one of two days, but does not know which. i suspect that the reason that papineau and durà-vilà locate the disanalogy where they do is that they have been distracted by the pre-measurement credential state of the everettian subject. on the account of everettian probability defended by papineau (see papineau [ ], [ ]), the pre- measurement subject should set her credences according to the branch weights even though she knows, with certainty, that there will be an up branch and that there will be a down branch. but the analogy between sb and confirmation in eqm can be made out entirely in terms of the post-measurement state of the observer, so pre-measurement credences are beside the point. peterson [ ] offers an alternative diagnosis of the disanalogy. although his discussion is rather hedged, the suggestion appears to amount to this. on awakening, beauty is uncertain about whether she has been previously awakened; however, on making a measurement, an agent certain that eqm is correct is sure that there is another branch on which another agent observes another result. beauty’s two wakings are connected in some way - peterson suggests either by personal identity or by causal or counterfactual dependency - in which two agents in different branches are not. why is this connection epistemically relevant? according to peterson, it is because this connection provides something additional for beauty to be uncertain about - whether or not she has been previously awakened. unfortunately, peterson doesn’t say why this additional uncertainty should affect beauty’s credences about the result of the coin. so as things stand, his account of the source of the disanalogy is no advance on that of papineau and durà-vilà. the diagnosis of the disanalogy that peterson offers does have a distinctive consequence, which points to a potential way of motivating this differential treatment of times and worlds. following through on his account of the disanalogy, peterson suggests that in sb variant cases where the agents who awaken after a toss of tails are distinct subjects, rather than being distinct time- slices of the same subject, the motivation for being a thirder disappears: ...in the beauty case, the thirder’s position seems correct; however, were the situation to involve not one person waking up twice but two successors being awoken once each... the halfer solution would be the correct one. peterson [ ] a similar view is defended by schwarz [ms], who argues that the correct answer to sb depends on whether it is construed as an episode of fission or not - that is, on whether the tuesday waker should be regarded as a ‘successor’ of the monday waker. schwarz motivates the view from general considerations about diachronic belief updating ; and peterson could help himself to this sort of motivation. however, the resulting picture is highly problematic. personal identity over time is a vague and arguably context-dependent business, and we can run a related arguments are given by meacham [ ]. meacham has confirmed (p.c.) that he accepts schwarz’ conclusions about rational belief in fission cases, though he’d resist schwarz’ further claims about chance and admissibility. sorites series from cases in which the sleeper who awakes on one day is definitely continuous with the sleeper who awakes on the next day to cases in which they are definitely distinct. peterson and schwarz are committed to saying that somewhere along this series there is a sharp discontinuity, where the credence that the subjects should have alters from / to / , even though the subjects may be unaware of where this discontinuity lies. moreover, this view does not altogether escape the pathological consequences associated with the halfer solution. for example, schwarz admits that on his account one of two fission products, about to toss a fair coin to determine whether the other fission product will be destroyed before awakening, should have / confidence that the fair coin will land heads (schwarz [ms] p. ). i take this to be a fatal difficulty for the approach; so i conclude that peterson has not correctly located the disanalogy between everettian confirmation and sb. . god’s gambling game in section i argued that the analogy between sb and confirmation in eqm breaks down because the result of the coin toss depends on a chancy process, while whether eqm or st is correct does not depend on any chancy process. the analogy can be restored if we consider a modified branching theory which i will call god’s gambling game: god’s gambling game: whenever a spin measurement is made, god tosses a fair coin to select either down or up. he then creates a branch in which this selected outcome is observed. he then tosses a further fair coin. if it lands heads he rests, his creative work done. if it lands tails he creates a second branch, in which the outcome not selected by the first coin toss is observed. this scenario is illustrated below: call the theory that god does carry out the procedure just outlined ggg. since this situation genuinely is analogous to the technicolour beauty scenario, does an analogue of the thirder effect arise? the answer is yes. if an agent knows that ggg is true, then after making a measurement, then even before he observes the result, that agent should become uncertain as to whether he is on the first branch to be created (in which case the second coin might have landed heads or tails), or whether he is on the second branch (in which case the second coin must have landed tails.) on making the measurement, then, the agent loses the evidence that whether there will be one branch or two is an effectively chancy matter. does this lead to a problematic automatic confirmation for ggg? the answer is no. it’s true that, via the standard thirder reasoning run through above, evidence that experiments have taken place does raise the probability that the world has multiplied conditional on ggg. but this result is irrelevant to our credence in ggg itself. reason to reassign credence amongst the various ways things could go conditional on a theory isn’t reason to change unconditional credence in that theory. this applies equally to sleeping beauty: if beauty isn’t certain that the procedure will go as promised (if she thinks maybe the experimenters were lying about what they’d do), then awakening doesn’t provide beauty with evidence – for example – that the coin used was fair. automatic confirmation of the many-worlds hypothesis over the single- world hypothesis for agents who are certain of ggg is altogether unsurprising, and it need cause no alarm for bayesian confirmation theorists. we have no good reason to assign any significant credence to ggg, so it matters not at all what our credences in the universe having branched conditional on ggg might be. if we were somehow to come to believe that god tosses a coin to decide, for every quantum interaction, whether the outcome was to be chancy or branchy, then we would indeed have reason to favour the hypothesis that there are many branches over the hypothesis that there is one branch. but this is all exactly as it should be. . non-chancy sleeping beauty cases the foregoing arguments have an interesting upshot for variants of sleeping beauty cases which lack the chancy element of the original case. in the mathematical sleeping beauty case (msb), uncertainty about the result of a fair coin toss is replaced by uncertainty about the truth of a mathematical proposition. on sunday night beauty has credence / that fermat’s last theorem is true. she will be awakened on monday if the theorem is true, and on both monday and tuesday (again with her memories from monday erased) if the theorem is false. beauty knows all this. the puzzle is to say what credence beauty should have on monday in the proposition that fermat’s last theorem is true (call this proposition true.) the setup of msb ensures that beauty is not a fully rational bayesian agent, since such agents are required to be logically omniscient. is there then any sense in asking what beauty’s credences ought to be? – after all, in one obvious sense, her credence in true ought to be . i think this question does make sense; it is common to distinguish diachronic and synchronic constraints on credences, and to evaluate an agent’s performance with respect to the diachronic constraints independently of her performance with respect to certain synchronic constraints (such as logical omniscience). epistemologists had certainly better hope that something like this is possible: we’re not in fact perfect bayesians, and agents with non-trivial degrees of belief in mathematical propositions need to be modelled by any plausible epistemology for mathematics. the difference between sb and msb may seem somewhat incidental. general considerations relating to topic-neutrality perhaps make it natural to assume that the two puzzles have the same solution. regardless, discussions of sb have usually paid little attention to the role that chance plays in the story . sb is usually described as a puzzle about self-location; and our two cases seem to involve structurally similar self-locating uncertainty. in both sb and msb, when she awakens on monday beauty is unsure whether it is monday or tuesday. in this section i will give some reasons for suspecting that the two puzzles may in fact have different solutions. two of the most powerful arguments for the answer / in sb (both of which appear in elga’s original article) are inapplicable to msb. moreover, the analogy between sb and confirmation in eqm gives us reason to prefer the answer / to msb. consider first the long-run frequency argument for the answer / . beauty knows that if sb is repeated infinitely many times, the ratio of tails-awakenings to heads-awakenings will (with chance ) tend to : . since any awakening is indistinguishable from any other, her credence that a randomly-chosen awakening is a heads-awakening should be / . this argument lapses in msb. the truth-value of mathematical propositions cannot vary between awakenings, so beauty knows that in the long-run either all the awakenings will be true- awakenings or all the awakenings will be false-awakenings . for example, christopher meacham remarks that ‘the chanciness of the coin toss only plays a superficial role in the argument.... the argument goes through just as well if heads and tails are replaced by two different hypotheses we have other reasons for having / / / credences in.’ (meacham [ ]). what if we pose different mathematical questions on each run of the experiment? this variable-question mathematical case will probably pattern with sb rather than with msb, since it seems inevitable that the procedure by which the questions are selected will involve a chance process at some stage or other. be that as it may, in this paper i will only address msb. consider now the principal principle argument for the answer / , set out in detail in section . this argument too lapses in msb. since mathematical propositions have objective chances of either zero or one , the constraint that the principal principle places on credence in mathematical propositions amounts to the requirement of logical omniscience, which is explicitly suspended in msb. accordingly, nothing in the setup of msb prohibits beauty from adopting credence / in true on being informed that it is monday, and hence nothing prohibits her from adopting credence / in true when she initially awakens on monday. i conclude that there are important disanalogies between msb and sb. two influential arguments for the thirder position in sb are inapplicable to the mathematical case. this provides reason to doubt whether our two cases have a uniform solution. moreover, the analogy between msb and confirmation in eqm provides an indirect argument for the answer / in msb. . conclusions the analogy between sb and everettian confirmation breaks down in a crucial way. whether heads or tails is true depends on the outcome of a chance process, while whether eqm or st is true does not depend on the outcome of any chance process. consequently, sb involves the loss of relevant evidence – evidence that the result of the coin is effectively chancy – while everettian confirmation scenarios involve no such loss. although bradley’s argument fails to establish the halfer conclusion in the case of sb, it does succeed in dispelling the spectre of automatic confirmation of eqm. everettians need not adopt any novel confirmation theory; given a correct conception of the evidence, eqm is confirmed just in the same way as ordinary stochastic theories. this result is doubly favourable to everettians. if i am right, then bayesian confirmation theory can be combined with eqm in a straightforward and non- pathological way, and everettians are not obliged to adopt the unpopular halfer position in sb. opponents of eqm would do better to target its metaphysics than to target its epistemology . this is so even according to ‘compatibilist’ conceptions of chance such as those of eagle [ ], glynn [ ] and handfield & wilson [ ]. this paper was presented at two events at monash university held in as part of the ahrc ’neglected problems of time’ project, led by toby handfield and graham oppy. § was also presented at the joint session . thanks to these audiences, and to an anonymous referee, for feedback; special thanks to rachael briggs, antony eagle, rohan french, al hájek, toby handfield, jenann ismael, peter lewis, chris meacham, dave ripley and wo schwarz. my greatest debt is to miranda rose, for the illustrations. references arntzenius, frank [ ]. ‘reflections on sleeping beauty’. analysis ( ): - . bostrom, nick [ ]. anthropic bias: observation selection effects in science and philosophy. london: routledge bradley, darren [ ]. ‘four problems about self-locating evidence’. synthèse ( ): - . bradley, darren [ ]. ‘self-location is no problem for conditionalization’. synthèse ( ): - . bradley, darren [ ]. ‘confirmation in a branching world: the everett interpretation and sleeping beauty’. british journal for 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(gev/c) using out-of-plane detection at bates and mainz [ ]. it has been established that the proton shape is slightly non-spherical. a chiral extrapolation [ ] of lattice qcd calculations [ ] is in good agreement with the data. – the electric and magnetic polarizabilities of the proton through measurement of virtual compton scattering from the proton at mainz [ ] and jlab [ ] and using out-of-plane detection at bates [ ]. – the quark and gluon contributions to the spin structure of the proton using deep inelastic scat- tering at hermes/desy [ ], jlab [ ], com- pass/cern [ ] and rhic-spin [ ]. – the role of strange quarks in the long distance mag- netic and electric charge distribution of the proton at bates, mainz and jlab [ , ]. there are hints of a non-zero strange quark magnetic moment of the pro- ton but these need to be confirmed by more precise experiments. here i concentrate on two areas of research where im- portant results have recently been obtained. the european physical journal a fig. . the jefferson lab data [ ] on the ratio g p e /g p m show- ing the discrepancy between the recoil polarization (solid cir- cles) and the rosenbluth (other symbols) techniques. evidence for multiple photon effects in elastic electron scattering from the proton essentially all electron scattering experiments to study proton and nuclear structure to date have been analyzed in terms of single photon exchange. the fine structure cou- pling constant α ∼ / is small enough that leading or- der has been adequate. there are a few specific examples where multiple photon exchange is known to be signif- icant, e.g. in comparison of electron and positron scat- tering in kinematics where the single photon exchange cross-section is small, or in radiative processes. thus, it came as a surprise when the jefferson lab hall a recoil polarization measurements of electron-proton elastic scat- tering at momentum transfers of about (gev/c) [ ] showed a substantial deviation from the data obtained over several decades with the rosenbluth technique [ ], which is based on precise cross-section measurements. this discrepancy has been interpreted as the effect of mul- tiple photon exchange in the elastic electron-proton cross- section [ ]. the cross section for elastic electron-proton scattering in the one-photon exchange approximation can be written in terms of the pointlike mott cross-section, the sachs form factors g p e and g p m and the electron scattering angle θ as dσ dΩ = ( dσ dΩ ) m ott · [ g p e + τg p m + τ + τg p m tan θ ] , where τ = q / m . figure shows the recoil polarization determination of g p e /g p m (solid circles) as a function of momentum transfer q . the rosenbluth data (all other data points) are believed to be uncorrected for the effects fig. . the quark and gluon momentum distributions at q = (gev/c) as a function of parton momentum x as de- termined by the zeus experiment [ ] at the hera electron- proton collider. note that the sea quark momentum xs and the gluon momentum xg distributions are divided by a factor of . of multiple photon exchange and so give an incorrect de- termination at higher q , i.e. above about (gev/c) . this multiple photon exchange contribution to elas- tic electron-proton scattering can be confirmed by precise comparison of electron-proton with positron proton elas- tic scattering or by measurement of the asymmetry ay in scattering of unpolarized electrons from a vertically polar- ized proton target [ ]. if confirmed, this is a very signifi- cant result. role of sea quarks in nucleon structure qcd tells us that the nucleon comprises three valence quarks and a sea of quark-antiquark pairs. from the ear- liest days of nuclear physics, these sea quarks in the form of mesons, have been viewed as playing an important role in the long distance structure of the nucleon e.g. the mag- nitude and sign of the proton and neutron magnetic mo- ments. in addition, the most successful hadronic theoreti- cal descriptions of light nuclei incorporate meson exchange between nucleons as an essential element of nuclear bind- ing. this “meson cloud” structure to the nucleon has gen- erally been accepted but has lacked both a rigorous the- oretical underpinning and a definitive quantitative basis from experiment. the role of valence quarks in nucleon structure has been studied extensively. the effects of sea quarks and gluons are relatively poorly determined, in large part be- cause they require high center-of-mass energy, and are a major focus of interest for the future [ ]. one of the im- portant contributions over the last decade has been the experimental measurement of deep inelastic scattering at high energies to determine the effects of the sea quarks and r.g. milner: the beauty of the electromagnetic probe fig. . comparison of the gluon and sea distributions from the zeus-s nlo qcd fit for various q values [ ] as measured at the hera electron-proton collider. gluons. in particular, data taken by experiments at the hera electron-proton collider [ ] have for the first time allowed a determination of the gluon momentum distribu- tion in the proton, as shown in fig. . the qcd evolution of hera data [ ] shows a significant sea contribution at low q , in contrast to the gluon contribution which van- ishes, as seen in fig. . this supports the point of view of a strong role for sea quarks at low q . at low energies, electron scattering experiments deter- mine the elastic electric and magnetic form factors of the proton and neutron. friedrich and walcher have postu- lated that the q dependence of the elastic form factors in the region . to . (gev/c) may be sensitive to the meson cloud structure of the nucleon and have produced parameterizations of world data which suggest that there may be experimental support for this ansatz [ ]. they fit the measured four form factors with a parameteriza- tion which consists of a smooth contribution and a bump contribution. figure shows the world’s data for the pro- ton elastic form factor plotted as a function of momentum transfer q , where the smooth contribution is subtracted. fig. . the proton charge elastic form-factor with the smooth contribution subtracted in the parameterization of friedrich and walcher [ ]. a % dip in the parameterization is obvious at q ∼ . – . (gev/c) , which coincides with the location of the peak in the neutron charge elastic form-factor gne. in the absence of realistic qcd calculations, it is hard to defini- tively state that this structure at low q is due to the meson cloud structure of the nucleon. however, it is a physically plausible explanation. blast experiment at mit-bates a new set of precision measurements of the low q elastic form factors of the proton and neutron have been carried out using the south hall ring (shr) at the mit-bates linear accelerator center. the bates large acceptance spectrometer toroid (blast) was constructed [ ] to de- tect scattered electrons, protons, neutrons and pions in the scattering of longitudinally polarized electrons with an en- ergy of mev from polarized targets of hydrogen and deuterium. the polarized internal gas target technique of- fers minimal systematic uncertainties and a high statistics sample of data were taken by the blast experiment over an eighteen month period from late to mid . the blast data are under analysis and will be able to provide new and independent experimental constraints of the friedrich-walcher ansatz. the polarized protons and deuterons (both vector and tensor) were produced using an atomic beam source (abs) [ ], which was located in the substantial and spa- tially varying magnetic field of the blast toroid. the target spin state was alternated every five minutes by switching the final rf transition immediately before the target to ensure equal target densities for each of the three states (vector +, vector −, tensor −). the electrons scat- tered from the polarized protons and deuterons in a cylin- drical, windowless aluminum target tube mm long, mm in diameter and with a wall thickness of µm. the polarized target was tuned and monitored using a breit-rabi system which continuously sampled the atomic polarization of a small fraction of the incoming beam from the abs. the vector polarizations of both the proton and deuteron was typically . . data were taken with stored electron beam intensities up to ma. the european physical journal a fig. . a schematic layout of the blast experiment at mit- bates. fig. . the vector asymmetry aved in quasielastic (e, e ′p) scat- tering from vector polarized deuterium as a function of missing momentum pm for . < q < . (gev/c) , as measured by the blast experiment [ ]. the polarized electron beam originated from a gaas polarized electron source and the storage ring was filled with alternating electron polarizations approximately ev- ery half hour. the longitudinal beam polarization at the target was maintained using a siberian snake solenoid sys- tem. the beam polarization was continuously monitored using a laser compton backscattering polarimeter, located upstream of the injection point in the shr. the average beam polarization over the blast data taking period was . . the blast (see fig. ) consisted of eight copper coils which provided a . tesla toroidal magnetic field. for these measurements it was instrumented with symmet- ric detectors in the horizontal plane: three drift chambers for momentum, angle and position determination; plastic scintillators for triggering and time of flight, and cerenkov detectors for pion rejection. in addition, large plastic scin- tillators for neutron detection were arranged on one side. the background rate for scattering from the target cell was measured and found to be negligible. figure shows a fraction of the blast data ac- quired in quasielastic (e, e′p) scattering from vector po- larized deuterium [ ]. the scattering asymmetry aved is plotted as a function of the missing momentum (pm) of the proton in the nucleon. the solid curve is the predic- tion of a monte carlo simulation which uses arenhövel’s theory [ ] as well as a realistic description of the exper- iment. at low pm, the scattering is dominated by the s- state in deuterium and the asymmetry is very close to that for scattering from a free proton. these data can be used to determine the product of beam and target vec- tor polarization. at high pm, the scattering is dominated by the d-state in the deuteron, where both proton and neutron spins are anti-aligned with respect to the nuclear spin. thus, the scattering asymmetry changes sign. the pm range of the data extend out to mev/c. blast data on the four elastic form factors of the proton and neutron are expected to be published in . in addi- tion, a sizable data set on electron scattering from tensor polarized deuterium was acquired with blast. conclusion the electromagnetic probe provides a beautiful and pre- cise means to study strongly interacting matter. we are fortunate to witness great advances in accelerator and ex- perimental technology so that the full power of the electro- magnetic probe can be exploited to study hadronic mat- ter. the two examples discussed above indicate that new insight into nature is being provided by the elementary elastic electron nucleon scattering reaction, particularly with spin polarization techniques. the role of the sea quarks/meson cloud in nucleon structure continues to be a subject of significant inter- est. precision determination of the elastic form factors at low momentum transfers from blast may confirm the ansatz of friedrich and walcher. confirmation of a dip in the proton electric and magnetic form factors as well as the neutron magnetic form factor at q ∼ . (gev/c) will not definitively quantify the role of the meson cloud but it will demand of theorists a convincing explanation. i note that the recent g data [ ] on the linear combi- nation of the electric and magnetic strange form factors of the proton suggest a q dependence at similar values of q to that of the dip. is this significant? clearly, more precise data are needed. the determination of gne as a function of q by many laboratories over a decade has clearly been a triumph for the field of electromagnetic nuclear physics. with the blast data, it is expected that this quantity will be de- termined to better than ± % at low momentum transfers. it is anticipated that this will quantitatively constrain the meson cloud contribution to the charge distribution of the neutron. the experimental and theoretical contributions at mami, particularly by our five distinguished colleagues who are honored here, have been important to the signifi- cant progress made worldwide. it has been a pleasure and a privilege to be part of this unique celebration. i con- gratulate profs. h. arenhövel, h. backe, d. drechsel, j. freidrich, k.-h. kasier, and th. walcher on their distin- guished careers and i wish them every success in the next phase of their lives. r.g. milner: the beauty of the electromagnetic probe the author would like to acknowledge discussions with a.m. bernstein, t.w. donnelly, r. miskamen, a.h. mueller, j.w. negele, and c.n. papanicolas. in addition, the author would like to acknowledge that the blast experiment is the fruit of a dedicated collaboration over an extended period of time. in particular, an outstanding cohort of graduate students is play- ing an essential role. the author’s research is supported by the united states department of energy under the cooperative agreement de-fg - er . references . r.g. edwards et al., phys. rev. lett. , ( ). . d. rohe et al., phys. rev. lett. , ( ). . t. eden et al., phys. rev. c , r ( ). . i. passchier et al., phys. rev. lett. , ( ). . r. madey et al., phys. rev. lett. , ( ). . n. sparveris et al., phys. rev. lett. , ( ). . v. pascalutsa, m. vanderhaeghen, phys. rev. lett. , ( ). . c. alexandrou et al., phys. rev. lett. , ( ). . j. roche et al., phys. rev. lett. , ( ). . g. laveissiere et al., phys. rev. lett. , ( ). . p. bourgeois et al., submitted to phys. rev. lett. 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( ) ( ). . p.a.m. guichon, m. vanderhaeghen, phys. rev. lett. , ( ); p.g. blunden, w. melnitchouk, j.a. tjon, phys. rev. lett. , ( ). . a.a. afanasev et al., phys. rev. d , ( ). . a. deshpande, r. milner, r. venugopalan, w. vogelsang, annu. rev. nucl. part. sci. , ( ). . s. chekanov et al., phys. rev. d , ( ). . j. friedrich, th. walcher, eur. phys. j. a , ( ). . blast technical design report august th, . . d. cheever et al., nucl. instrum. methods a , ( ). . a. maschinot, mit phd thesis (unpublished). . h. arenhövel, w. leidemann, e.l. tomusiak, phys. rev. c , ( ); , ( ); z. phys. a , ( ); , ( ). . the g collaboration, phys. rev. lett. , ( ). introduction evidence for multiple photon effects in elastic electron scattering from the proton role of sea quarks in nucleon structure blast experiment at mit-bates conclusion durham research online deposited in dro: may version of attached �le: accepted version peer-review status of attached �le: peer-reviewed citation for published item: grinfeld, michael and volkov, stanislav and wade, andrew r. ( ) 'convergence in a multidimensional randomized keynesian beauty contest.', advances in applied probability., ( ). pp. - . further information on publisher's website: http://dx.doi.org/ . /aap/ publisher's copyright statement: additional information: use policy the full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro�t purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in dro • the full-text is not changed in any way the full-text must not be sold in any format or medium without the formal permission of the copyright holders. please consult the full dro policy for further details. durham university library, stockton road, durham dh ly, united kingdom tel : + ( ) | fax : + ( ) https://dro.dur.ac.uk https://www.dur.ac.uk http://dx.doi.org/ . /aap/ http://dro.dur.ac.uk/ / https://dro.dur.ac.uk/policies/usepolicy.pdf https://dro.dur.ac.uk applied probability trust ( th march ) convergence in a multidimensional randomized keynesian beauty contest michael grinfeld,∗ university of strathclyde stanislav volkov,∗∗ lund university and university of bristol andrew r. wade,∗∗∗ durham university abstract we study the asymptotics of a markovian system of n ≥ particles in [ , ]d in which, at each step in discrete time, the particle farthest from the current centre of mass is removed and replaced by an independent u[ , ]d random particle. we show that the limiting configuration contains n − coincident particles at a random location ξn ∈ [ , ] d. a key tool in the analysis is a lyapunov function based on the squared radius of gyration (sum of squared distances) of the points. for d = we give additional results on the distribution of the limit ξn, showing, among other things, that it gives positive probability to any nonempty interval subset of [ , ], and giving a reasonably explicit description in the smallest nontrivial case, n = . keywords: keynesian beauty contest; radius of gyration; rank-driven process; sum of squared distances. mathematics subject classification: primary j secondary d ; f ; k ; c ; a . introduction, model, and results in a keynesian beauty contest, n players each guess a number, the winner being the player whose guess is closest to the mean of all the n guesses; the name marks keynes’s discussion of “those newspaper competitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average preferences of the competitors as a whole” [ , ch. , §v]. moulin [ , p. ] formalized a version of the game played on a real interval, the “p-beauty contest”, in which the target is p (p > ) times the mean value. see e.g. [ ] and references therein for some recent work on game-theoretic aspects of such “contests” in economics. in this paper we study a stochastic process based on an iterated version of the game, in which players randomly choose a value in [ , ], and at each step the worst performer ∗ postal address: department of mathematics and statistics, university of strathclyde, richmond street, glasgow g xh, uk. ∗∗ postal address: centre for mathematical sciences, lund university, box se- , lund, sweden, and department of mathematics, university of bristol, university walk, bristol bs tw, uk. ∗∗∗ postal address: department of mathematical sciences, durham university, south road, durham dh le, uk. michael grinfeld, stanislav volkov, andrew r. wade (that is, the player whose guess is farthest from the mean) is replaced by a new player; each player’s guess is fixed as soon as they enter the game, so a single new random value enters the system at each step. analysis of this model was posed as an open problem in [ , p. ]. the natural setting for our techniques is in fact a generalization in which the values live in [ , ]d and the target is the barycentre (centre of mass) of the values. we now formally describe the model and state our main results. let d ∈ n := { , , . . .}. we use the notation xn = (x , x , . . . , xn) for a vector of n points xi ∈ r d. we write µn(xn) := n − ∑n i= xi for the barycentre of xn, and ‖ · ‖ for the euclidean norm on rd. let ord(xn) = (x( ), x( ), . . . , x(n)) denote the barycentric order statistics of x , . . . , xn, so that ‖x( ) − µn(xn)‖ ≤ ‖x( ) − µn(xn)‖ ≤ · · · ≤ ‖x(n) − µn(xn)‖; any ties are broken randomly. we call x ∗ n := x(n) the extreme point of xn, a point of x , . . . , xn farthest from the barycentre. we define the core of xn as x ′n := (x( ), . . . , x(n− )), the vector of x , . . . , xn with the extreme point removed. the markovian model that we study is defined as follows. fix n ≥ . start with x ( ), . . . , xn( ), distinct points in [ , ] d, and write xn ( ) := (x( )( ), . . . , x(n)( )) for the corresponding ordered vector. one possibility is to start with a uniform random initial configuration, by taking x ( ), . . . , xn( ) to be independent u[ , ] d random variables; here and elsewhere u[ , ]d denotes the uniform distribution on [ , ]d. in this uniform random initialization, all n points are indeed distinct with probability . given xn(t), replace x ∗ n(t) = x(n)(t) by an independent u[ , ] d random variable ut+ , so that xn (t + ) = ord(x( )(t), . . . , x(n− )(t), ut+ ). the interesting case is when n ≥ : the case n = is trivial, and the case n = is also uninteresting since at each step either point is replaced with probability / by a u[ , ] variable, so that, regardless of the initial configuration, after a finite number of steps we will have two independent u[ , ] points. our main result, theorem . , shows that for n ≥ all but the most extreme point of the configuration converge to a common limit. theorem . . let d ∈ n and n ≥ . let xn( ) consist of n distinct points in [ , ] d. there exists a random ξn := ξn (xn( )) ∈ [ , ] d such that x ′n(t) a.s. −→ (ξn , ξn, . . . , ξn ), and x ∗ n(t) − ut a.s. −→ , ( . ) as t → ∞. in particular, for u ∼ u[ , ]d, as t → ∞, xn(t) d −→ (ξn, ξn, . . . , ξn, u). remark . . under the conditions of theorem . , despite the fact that x ∗n (t)−ut → a.s., we will see below that x ∗n (t) = ut infinitely often a.s. theorem . is proved in section . then, section is devoted to the one-dimensional case, where we obtain various additional results on the limit ξn. finally, the appen- dices, a and b, collect some results on uniform spacings and continuity of distributional fixed-points that we use in parts of the analysis in section . . proof of convergence intuitively, the evolution of the process is as follows. if, on replacement of the extreme point, the new point is the next extreme point (measured with respect to the randomized keynesian beauty contest new centre of mass), then the core is unchanged. however, if the new point is not extreme, it typically penetrates the core significantly, while a more extreme point is thrown out of the core, reducing the size of the core in some sense (we give a precise statement below). tracking the evolution of the core, by following its centre of mass, one sees increasingly long periods of inactivity, since as the size of the core decreases changes occur less often, and moreover the magnitude of the changes decreases in step with the size of the core. the dynamics are nontrivial, but bear some resemblance to random walks with decreasing steps (see e.g. [ , ] and references therein) as well as processes with reinforcement such as the pólya urn (see e.g. [ ] for a survey). the process is also reminiscent in some ways of iterated interval division [ ] or sequential adsorption with interaction [ ]. our analysis will rest on a ‘lyapunov function’ for the process, that is, a function of the configuration that possesses pertinent asymptotic properties. one may initially hope, for example, that the diameter of the point set xn(t) would decrease over time, but this cannot be the case because the newly added point can be anywhere in [ , ]d. what then about the diameter of x ′n(t), for which the extreme point is ignored? we will show later in this section that this quantity is in fact well behaved, but we have to argue somewhat indirectly: the diameter of x ′n(t) can increase (at least for n big enough; see remark . below). however, there is a monotone decreasing function associated with the process, based on the sum of squared distances of a configuration, which we will use as our lyapunov function. to define this function (see ( . ) below) we need some notation. for n ∈ n and xn = (x , x , . . . , xn) ∈ (r d)n, write gn(xn) := gn(x , . . . , xn) := n − n ∑ i= i− ∑ j= ‖xi − xj‖ = n ∑ i= ‖xi − µn(xn)‖ ; ( . ) a detailed proof of the (elementary) final equality in ( . ) may be found on pp. – of [ ], for example. we remark that n gn is the squared radius of gyration of x , . . . , xn: see e.g. [ ], p. . note also that calculus verifies the useful variational formula gn(x , . . . , xn) = inf y∈rd n ∑ i= ‖xi − y‖ . ( . ) for n ≥ , define fn(xn) := fn(x , . . . , xn) := gn− (x ′ n) = gn− (x( ), . . . , x(n− )). lemma . . let n ≥ and xn = (x , x , . . . , xn) ∈ (r d)n. then for any x ∈ rd, fn(x( ), . . . , x(n− ), x) ≤ fn(xn). proof. for ease of notation, we write simply (x , . . . , xn) for (x( ), . . . , x(n)), i.e., we relabel so that xj is the jth closest point to µn(xn). then x ∗ n = xn, x ′ n = (x , . . . , xn− ), and fold := fn(xn) = gn− (x , . . . , xn− ) = n− ∑ i= ‖xi − µ ′ old‖ , ( . ) michael grinfeld, stanislav volkov, andrew r. wade where µ′old := µn− (x ′ n). we compare fold to fn evaluated on the set of points obtained by removing xn and replacing it with some x ∈ r d. write y := {x , . . . , xn− , x} ∗ for the new extreme point. then fnew := fn(x , . . . , xn− , x) = n− ∑ i= ‖xi − µ ′ new‖ + ‖x − µ′new‖ − ‖y − µ′new‖ , ( . ) where µ′new := n − ( n− ∑ i= xi + x − y ) = µ′old + x − y n − . ( . ) denote µnew := µn(x , . . . , xn− , x), so µ′new = nµnew n − − y n − . ( . ) from ( . ), ( . ), and ( . ), we obtain fnew − fold = n− ∑ i= ( ‖xi − µ ′ new‖ − ‖xi − µ ′ old‖ ) + ‖x − µ′new‖ − ‖y − µ′new‖ . ( . ) for the sum on the right-hand side of ( . ), we have that n− ∑ i= ( ‖xi − µ ′ new‖ − ‖xi − µ ′ old‖ ) = n− ∑ i= ( xi · (µ ′ old − µ ′ new) + ‖µ ′ new‖ − ‖µ′old‖ ) = (n − ) ( µ′old · (µ ′ old − µ ′ new) + ‖µ ′ new‖ − ‖µ′old‖ ) = (n − ) ( ‖µ′old‖ − (µ′old · µ ′ new) + ‖µ ′ new‖ ) . simplifying this last expression and substituting back into ( . ) gives fnew − fold = (n − )‖µ′old − µ ′ new‖ + ‖x − µ′new‖ − ‖y − µ′new‖ . thus, using ( . ) and then ( . ), fnew − fold = ‖x − y‖ n − + ‖x‖ − ‖y‖ − µ′new · (x − y) = ‖x‖ + ‖y‖ − x · y n − + ‖x‖ − ‖y‖ − ( nµnew n − − y n − ) · (x − y). hence we conclude that fnew − fold = n n − ( ‖x‖ − ‖y‖ − µnew · (x − y) ) = n n − ( ‖x − µnew‖ − ‖y − µnew‖ ) ≤ , ( . ) since y is, by definition, the farthest point from µnew. now we return to the stochastic model. define f(t) := fn(xn (t)). ( . ) lemma . has the following immediate consequence. randomized keynesian beauty contest corollary . . let n ≥ . then f(t + ) ≤ f(t). corollary . shows that our lyapunov function f(t) is nonincreasing; later we show that f(t) → a.s. (see lemma . below). first, we need to relate f(t) to the diameter of the point set x ′n(t). for n ≥ and x , . . . , xn ∈ r d, write dn(x , . . . , xn) := max ≤i,j≤n ‖xi − xj‖. lemma . . let n ≥ and x , . . . , xn ∈ r d. then dn(x , . . . , xn) ≤ gn(x , . . . , xn) ≤ (n − )dn(x , . . . , xn) . remark . . the lower bound in lemma . is sharp, and is attained by collinear configurations with two diametrically opposed points xi, xj and all the other n− points at the midpoint µ (xi, xj) = µn(x , . . . , xn). the upper bound in lemma . is not, in general, sharp; determining the sharp upper bound is a nontrivial problem. the bound gn(x , . . . , xn) ≤ n ( d d+ ) dn(x , . . . , xn) from [ ] is also not always sharp. witsenhausen [ ] conjectured that the maximum is attained if and only if the points are distributed as evenly as possible among the vertices of a regular d-dimensional simplex of edge-length dn(x , . . . , xn); this was proved relatively recently [ , ]. proof of lemma . . fix x , . . . , xn ∈ r d. for ease of notation, write µ = µn(x , . . . , xn). first we prove the lower bound. for n ≥ , using the second form of gn in ( . ), gn(x , . . . , xn) = n ∑ i= ‖xi − µ‖ ≥ ‖xi − µ‖ + ‖xj − µ‖ , for (xi, xj) a diameter, i.e., dn(x , . . . , xn) = ‖xi − xj‖. by the n = case of ( . ), ‖xi − µ‖ + ‖xj − µ‖ ≥ ‖xi − µ (xi, xj)‖ = ‖xi − xj‖ . this gives the lower bound. for the upper bound, from the first form of gn in ( . ), gn(x , . . . , xn) ≤ n n ∑ i= (i − )dn(x , . . . , xn) , by the definition of dn, which yields the result. let d(t) := dn− (x ′ n (t)). remark . . by lemma . (or ( . )), g (x ′ (t)) = d (x ′ (t)) , so when n = , lemma . implies that d(t + ) ≤ d(t) a.s. as well. if d = , it can be shown that d(t) is nonincreasing also when n = . in general, however, d(t) can increase. let ft := σ(xn ( ), xn( ), . . . , xn(t)), the σ-algebra generated by the process up to time t. let b(x; r) denote the closed euclidean d-ball with centre x ∈ rd and radius r > . define the events at+ := {ut+ ∈ b(µn− (x ′ n (t)); d(t))}, a ′ t+ := {ut+ ∈ b(µn− (x ′ n (t)); d(t)/ )}. michael grinfeld, stanislav volkov, andrew r. wade lemma . . there is an absolute constant γ > for which, for all n ≥ and all t, a′t+ ⊆ {f(t + ) − f(t) ≤ −γn − f(t)} ⊆ {f(t + ) − f(t) < } ⊆ at+ . ( . ) moreover, there exist constants c > and c < ∞, depending only on d, for which, for all n ≥ and all t, a.s., p [ f(t + ) − f(t) ≤ −γn− f(t) | ft ] ≥ p[a′t+ | ft] ≥ cn −d/ (f(t))d/ ; ( . ) p [f(t + ) − f(t) < | ft] ≤ p[at+ | ft] ≤ c(f(t)) d/ . ( . ) proof. for simplicity we write x , . . . , xn− instead of x( )(t), . . . , x(n− )(t) and d instead of d(t) = dn− (x , . . . , xn− ). by definition of d, there exists some i ∈ { , . . . , n − } such that ‖µ′old − xi‖ ≥ d/ , where µ ′ old = µn− (x , . . . , xn− ). given ft, the event a ′ t+ , that the new point u := ut+ falls in b(µ ′ old; d/ ), has probability bounded below by θdd d, where θd > depends only on d. let µnew := µn(x , . . . , xn− , u). suppose that a ′ t+ occurs. then, ‖µnew − µ ′ old‖ = n ‖u − µ′old‖ ≤ d n ≤ d , ( . ) since n ≥ . hence, by ( . ) and the triangle inequality, ‖u − µnew‖ ≤ ‖u − µ ′ old‖ + ‖µnew − µ ′ old‖ ≤ d + d = d . ( . ) on the other hand, by another application of the triangle inequality and ( . ), ‖µnew − xi‖ ≥ ‖µ ′ old − xi‖ − ‖µnew − µ ′ old‖ ≥ d − d = d . then, by definition, the extreme point y := {x , . . . , xn− , u} ∗ satisfies ‖y − µnew‖ ≥ ‖µnew − xi‖ ≥ d . ( . ) hence from the x = u case of ( . ) with the bounds ( . ) and ( . ), we conclude f(t + ) − f(t) ≤ n n − ( ( d ) − ( d ) ) (a′t+ ) ≤ − d (a′t+ ), ( . ) for all n ≥ ; the first inclusion in ( . ) follows (with γ = / ) from ( . ) together with the fact that, by the second inequality in lemma . , d ≥ n− f(t). this in turn implies ( . ), using the fact that p[a′t+ | ft] ≥ θdd d. next we consider the event at+ . using the same notation as above, we have that ‖µnew − u‖ ≥ ‖µ ′ old − u‖ − ‖µnew − µ ′ old‖ = ( − n ) ‖µ′old − u‖, by the equality in ( . ). also, for any k ∈ { , . . . , n − }, ‖µnew − xk‖ ≤ ‖µ ′ old − xk‖ + ‖µ ′ old − µnew‖ ≤ d + n ‖µ′old − u‖, randomized keynesian beauty contest by ( . ) again. combining these estimates we obtain, for any k ∈ { , . . . , n − }, ‖µnew − u‖ − ‖µnew − xk‖ ≥ ( − n ) ‖µ′old − u‖ − d ≥ ‖µ′old − u‖ − d, for n ≥ . so in particular, ‖µnew − u‖ > ‖µnew − xk‖ for all k ∈ { , . . . , n − } provided ‖µ′old − u‖ > d, i.e., u /∈ b(µ ′ old; d). in this case, u is the extreme point among u, x , . . . , xn− , i.e., act+ ⊆ {x ∗ n(t + ) = ut+ }. ( . ) in particular, on act+ , f(t + ) = f(t), and f(t + ) < f(t) only if at+ occurs, giving the final inclusion in ( . ). since p[at+ | ft] is bounded above by cdd d for a constant cd < ∞ depending only on d, ( . ) follows from the first inequality in lemma . . this completes the proof. lemma . . suppose that n ≥ . then, as t → ∞, f(t) → a.s. and in l . proof. let ε > and let σ := min{t ∈ z+ : f(t) ≤ ε}, where z+ := { , , , . . .}. then by ( . ), there exists δ > (depending on d, ε, and n) such that, a.s., p [f(t + ) − f(t) ≤ −δ | ft] ≥ δ {t < σ}. hence, since f(t + ) − f(t) ≤ a.s. by corollary . , e [f(t + ) − f(t) | ft] ≤ −δ {t < σ}. ( . ) by corollary . , f(t) is nonnegative and nonincreasing, and hence f(t) converges a.s. as t → ∞ to some nonnegative limit f(∞); the convergence also holds in l since f(t) is uniformly bounded. in particular, e[f(t)] → e[f(∞)]. so taking expectations in ( . ) and letting t → ∞ we obtain lim sup t→∞ δ p[σ > t] ≤ , which implies that p[σ > t] → as t → ∞. thus σ < ∞ a.s., which together with the monotonicity of f(t) (corollary . ) implies that f(t) ≤ ε for all t sufficiently large. since ε > was arbitrary, the result follows. recall the definition of at and a ′ t from before lemma . . define (ft) stopping times τ := and, for n ∈ n, τn := min{t > τn− : at occurs}. then f(t) < f(t − ) can only occur if t = τn for some n. since p[at+ | ft] is bounded below by cf(t) d/ for some c > , it is not hard to see that, provided f( ) > , at occurs infinitely often, a.s. indeed, suppose that f( ) > and at occurs only finitely often. then f(t) has a non-zero limit. on the other hand, ∑ t cf(t) d/ ≤ ∑ t p[at+ | ft] < ∞, by lévy’s extension of the borel–cantelli lemma, so that f(t) → a.s., which is a contradiction. hence τn < ∞, a.s., for all n. lemma . . let n ≥ . there exists α > such that, a.s., d(τn) ≤ e −αn for all n sufficiently large. michael grinfeld, stanislav volkov, andrew r. wade proof. we have from ( . ) and the second inequality in lemma . that f(τn) − f(τn − ) ≤ −δf(τn − ) (a ′ τn ), for some δ > . note also that, by definition of the stopping times τn, f(τn − ) = f(τn− ). hence, p[f(τn) − f(τn− ) ≤ −δf(τn− ) | fτn− ] ≥ p[a ′ τn | fτn− ] ≥ δ, taking δ > small enough, since, using the fact that (aτn) = a.s., p[a′τn | fτn− ] = e [ p[a′τn | fτn] (aτn) | fτn− ] = e [ p[a′τn | aτn] | fτn− ] , where by definition of at and a ′ t, p[a ′ τn | aτn] is uniformly positive. since f(t + ) − f(t) ≤ a.s. (by corollary . ) it follows that e [ f(τn) − f(τn− ) | fτn− ] ≤ −δ f(τn− ). taking expectations, we obtain e[f(τn)] ≤ ( − δ )e[f(τn− )], which implies that e[f(τn)] = o(e −cn), for some c > depending on δ. then by markov’s inequality, p[f(τn) ≥ e −cn/ ] = o(e−cn/ ), which implies that f(τn) = o(e −cn/ ), a.s., by the borel–cantelli lemma. then the first inequality in lemma . gives the result. remark . . the proof of lemma . shows that p[a′τn | fτn− ] is uniformly positive, so lévy’s version of the borel–cantelli lemma, with the fact that τn < ∞ a.s. for all n, shows that a′t occurs for infinitely many t, a.s. with the proof of lemma . , this shows that x ∗n(t) = ut infinitely often, as claimed in remark . . we are almost ready to complete the proof of theorem . . we state the main step in the remaining argument as the first part of the the next lemma, while the second part of the lemma we will need in section . below. for ε > , define the stopping time νε := min{t ∈ n : f(t) < ε }; for any ε > , νε < ∞ a.s., by lemma . . lemma . . let n ≥ . then there exists ξn ∈ [ , ] d such that µn− (x ′ n (t)) → ξn a.s. and in l as t → ∞. moreover, there exists an absolute constant c such that for any ε > , and any t ∈ n, on {νε ≤ t }, a.s., e [ max t≥t ‖µn− (x ′ n (t)) − µn− (x ′ n (t ))‖ | ft ] ≤ cε. proof. let µ′(t) := µn− (x ′ n (t)). observe that for n ≥ , x ′ n (t) and x ′ n(t − ) have at least one point in common; choose one such point, and call it z(t). then µ′(t) ∈ hull x ′n(t) ⊆ hull xn(t), where hull x denotes the convex hull of the point set x . so ‖z(t) − µ′(t)‖ ≤ d(t). similarly ‖z(t) − µ′(t − )‖ ≤ d(t − ). by definition of τn, µ ′(t) = µ′(t − ) and d(t) = d(t − ) unless t = τn for some n, in which case µ′(τn − ) = µ ′(τn− ) and d(τn − ) = d(τn− ). hence, ∑ t≥ ‖µ′(t) − µ′(t − )‖ = ∑ n≥ ‖µ′(τn) − µ ′(τn− )‖ ≤ ∑ n≥ (‖µ′(τn) − z(τn)‖ + ‖µ ′(τn− ) − z(τn)‖) , ( . ) randomized keynesian beauty contest by the triangle inequality. then the preceding remarks imply that ∑ t≥ ‖µ′(t) − µ′(t − )‖ ≤ ∑ n≥ (d(τn) + d(τn− )) < ∞, a.s., by lemma . . hence there is some (random) ξn ∈ [ , ] d for which µ′(t) → ξn a.s. as t → ∞, and l convergence follows by the bounded convergence theorem. for the final statement in the lemma we use a variation of the preceding argument. let m := max{n ∈ z+ : τn ≤ t }. then f(t ) = f(τm ) and µ ′(τm ) = µ ′(t ), so that on {νε ≤ t }, we have {νε ≤ τm } as well. hence (by corollary . ) f(τm ) < ε . a similar argument to that in the proof of lemma . shows that, for m ≥ , e[f(τm+m) | ft ] ≤ e −cm e[f(τm ) | ft ] ≤ ε e−cm, on {νε ≤ t }, where c > depends on n but not on m or ε. thus by lemma . , on {νε ≤ t }, e[d(τm+m) | ft ] ≤ ε e−cm. also, similarly to ( . ), max t≥τm ‖µ′(t) − µ′(τm )‖ ≤ ∑ t≥τm ‖µ′(t) − µ′(t − )‖ ≤ ∑ m≥ (d(τm+m) + d(τm+m− )) . taking expectations and using the cauchy–schwarz inequality, we obtain, on {νε ≤ t }, e [ max t≥t ‖µ′(t) − µ′(t )‖ | ft ] = e [ max t≥τm ‖µ′(t) − µ′(τm )‖ | ft ] ≤ ε ec ∑ m≥ e−cm, a constant times ε . jensen’s inequality now gives the result, with c = −e−c . proof of theorem . . again let µ′(t) := µn− (x ′ n(t)). we have from lemma . that µ′(t) → ξn a.s. now, for any j ∈ { , . . . , n − }, by the triangle inequality, ‖x(j)(t) − ξn ‖ ≤ ‖x(j)(t) − µ ′(t)‖ + ‖µ′(t) − ξn‖ ≤ d(t) + ‖µ ′(t) − ξn‖, which tends to a.s. as t → ∞, since d(t) → a.s. by lemma . . this establishes the first statement in ( . ). moreover, by ( . ), x ∗n(t+ ) = ut+ only if at+ occurs. on at+ , x ∗ n(t + ) is one of the points of x ′ n(t), and so ‖x ∗ n(t + ) − µ ′(t)‖ ≤ d(t). in addition, on at+ , we have ‖ut+ − µ ′(t)‖ ≤ d(t). so by the triangle inequality, ‖x ∗n(t + ) − ut+ ‖ ≤ d(t) (at+ ), which tends to a.s., again by lemma . . this gives the final part of ( . ). . the limit distribution in one dimension . . overview and simulations throughout this section we restrict attention to d = . of interest is the distribution of the limit ξn in ( . ), and its behaviour as n → ∞. simulations suggest that ξn is highly dependent on the initial configuration: figure shows histogram estimates for ξn from repeated simulations with a deterministic initial condition. in more detail, michael grinfeld, stanislav volkov, andrew r. wade runs of each simulation were performed, each starting from the same initial condition; each run was terminated when d(t) < . for the first time, and the value of µn− (x ′ n(t)) was output as an approximation to ξn (cf theorem . ). note that, by ( . ), in the simulations one may take the new points not u[ , ] but uniform on a typically much smaller interval, which greatly increases the rate of updates to the core configuration. . . . . . . . . . . . . figure : normalized histograms each based on simulations, with n = and initial points , , (left) and n = and initial points k , k ∈ { , . . . , } (right). figure shows sample results obtained with an initial condition of n i.i.d. u[ , ] random points. now the histograms appear much simpler, although, of course, they can be viewed as mixtures of complicated multi-modal histograms similar to those in figure . in the uniform case, it is natural to ask whether ξn converge in distribution to some limit distribution as n → ∞. the form of the histograms in figure might suggest a beta distribution (this is one sense in which the randomized beauty contest is “reminiscent of a pólya urn” [ , p. ]). an ad-hoc kolmogorov–smirnov analysis (see table . ) suggests that the distributions are indeed ‘close’ to beta distributions, but different enough for the match to be unconvincing. simulations for large n are computationally intensive. we remark that it is not unusual for beta or ‘approximate beta’ distributions to appear as limits of schemes that proceed via iterated procedures on intervals: see for instance [ ] and references therein. n β κ(β) . . . . . . . . table : κ(β) is the kolmogorov–smirnov distance between a beta(β, β) distribution and the empirical distribution from the samples of size plotted in figure , minimized over β in each case. randomized keynesian beauty contest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . figure : normalized histograms for simulations with random i.i.d. uniform initial conditions, with (top row) n = , and (bottom row) n = , . in the rest of this section we study ξn and its distribution. our results on the limit distribution, in particular, leave several interesting open problems, including a precise description of the phenomena displayed by the simulations reported above. in section . we give an alternative (one might say ‘phenomenological’) characterization of the limit ξn , and contrast this with an appropriate rank-driven process in the sense of [ ]. in section . we show that the distribution of ξn is fully supported on ( , ) and assigns positive probability to any proper interval, using a construction permitting transformations of configurations. finally, section . is devoted to the case n = , for which some explicit computations for the distribution of ξn (in particular, its moments) are carried out. . . a characterization of the limit let πn(t) := t # {s ∈ { , , . . . , t} : x ∗n(s) < µn(xn(s))} , michael grinfeld, stanislav volkov, andrew r. wade the proportion of times up to time t for which the extreme point was the leftmost point (as opposed to the rightmost). the next result shows that πn (t) converges to the (random) limit ξn given by theorem . ; we give the proof after some additional remarks. proposition . . let d = and n ≥ . then limt→∞ πn (t) = ξn a.s. it is instructive to contrast this behaviour with a suitable rank-driven process (cf [ ]). namely, fix a parameter π ∈ ( , ). take n points in [ , ], and at each step in discrete time replace either the leftmost point (with probability π) or else the rightmost point (probability −π), independently at each step; inserted points are independent u[ , ] variables. for this process, results of [ ] show that the marginal distribution of a typical point converges (as t → ∞ and then n → ∞) to a unit point mass at π (cf remark . in [ ]). this leads us to one sense in which the randomized beauty contest is, to a limited extent, “reminiscent of a pólya urn” [ , p. ]. recall that a pólya urn consists of an increasing number of balls, each of which is either red or blue; at each step in discrete time, a ball is drawn uniformly at random from the urn and put back into the urn together with an extra ball of the same colour. the stochastic process of interest is the proportion of red balls, say; it converges to a random limit π′, which has a beta distribution. the beauty contest can be viewed as occupying a similar relation to the rank-driven process described above as the pólya urn process does to the simpler model in which, at each step, independently, either a red ball is added to the urn (with probability π′) or else a blue ball is added (probability − π′). proof of proposition . . given τ , τ , τ , . . ., ξn = limn→∞ µn− (x ′ n(τn)) is in- dependent of ut, t /∈ {τ , τ , . . .}, since, by ( . ), any such ut is replaced at time t + . let ε > . by theorem . , there exists a random t < ∞ a.s. for which max ≤i≤n− |ξn − x(i)(t)| ≤ ε for all t ≥ t . since µn(xn(t + )) = n− n µn− (x ′ n(t)) + n ut+ , we have that for t ≥ t , using the triangle inequality, for any i ∈ { , . . . , n − }, |µn(xn (t + )) − x(i)(t)| ≤ ε + |µn(xn(t + )) − ξn| ≤ ε + n − n |µn− (x ′ n(t)) − ξn | + n |ut+ − ξn |. hence, for t ≥ t , max ≤i≤n− ∣ ∣x(i)(t) − µn(xn(t + )) ∣ ∣ ≤ n |ξn − ut+ | + ε. ( . ) on the other hand, for t ≥ t , µn(xn (t + )) ≥ n− n (ξn − ε) + n ut+ , so that for i ∈ { , . . . , n − }, µn(xn (t + )) − ut+ ≥ n − n (ξn − ut+ − ε). ( . ) randomized keynesian beauty contest suppose that ut+ < ξn − kε for some k ∈ ( , ∞). then, from ( . ) and ( . ), |µn(xn (t + )) − ut+ | − max ≤i≤n− ∣ ∣x(i)(t) − µn(xn(t + )) ∣ ∣ ≥ n − n (ξn − ut+ ) − n − n ε > ε n ((n − )k − n + ) . this last expression is positive provided k ≥ n− n− , which is the case for all n ≥ with the choice k = , say. hence, with this choice of k, {ut+ < ξn − ε} implies that ut+ is farther from µn+ (xn(t + )) than is any of the points left over from x ′n(t). write lt := {ut < ξn − ε}. then we have shown that, for t ≥ t , the event lt implies that ut = x ∗ n(t), and, moreover, ut < µn(xn (t)). hence, for t ≥ t , πn(t) ≥ t t ∑ s=t (ls) ≥ t t ∑ s=t s/∈{τ ,τ ,...} (ls). given τ , τ , . . ., us, s /∈ {τ , τ , . . .} are independent of t and ξn. for such an s, us is uniform on is := [ , ] \ b(µn− (x ′ n (s)); d(s)), and, for s ≥ t , d(s) ≤ ε so that is ⊇ [ , max{ξn − ε, }] ∪ [min{ξn + ε, }, ]. hence, given s /∈ {τ , τ , . . .} and s ≥ t , p[ls] = p[us < ξn − ε | us ∈ is] ≥ ξn − ε. hence, considering separately the cases ξn > ε and ξn ≤ ε, the strong law of large numbers implies that t t ∑ s=t s/∈{τ ,τ ,...} (ls) ≥ ξn − ε, for all t sufficiently large; here we have used the fact that t − t → ∞ a.s. as t → ∞ and #{n ∈ z+ : τn ≤ t} = o(t) a.s., which follows from ( . ) and lemma . with a standard concentration argument using e.g. the azuma–hoeffding inequality. since ε > was arbitrary, it follows that lim inft→∞ t − πn(t) ≥ ξn a.s. the sym- metrical argument considering events of the form rt := {ut > ξn + ε} shows that lim inft→∞( − t − πn(t)) ≥ − ξn a.s., so lim supt→∞ t − πn(t) ≤ ξn a.s. combining the two bounds gives the result. . . the limit has full support in this section, we prove that ξn is fully supported on ( , ) in the sense that ess inf ξn = , ess sup ξn = , and ξn assigns positive probability to any non-null interval. let mn( ) := min{‖xi( ) − xj( )‖ : i, j ∈ { , , . . . , n + }, i = j}, ( . ) where we use the conventions x ( ) := and xn+ ( ) := . for ρ > let sρ denote the f -event sρ := {mn( ) ≥ ρ} that no point of xn( ) is closer than distance ρ to any other point of xn( ) or to either of the ends of the unit interval. michael grinfeld, stanislav volkov, andrew r. wade proposition . . let d = and n ≥ . let ρ ∈ ( , ). for any non-null interval subset i of [ , ], there exists δ > (depending on n, i, and ρ) for which p[ξn ∈ i | xn( )] ≥ δ (sρ), a.s. ( . ) in particular, in the case where xn( ) consists of n independent u[ , ] points, p[ξn ∈ i] > for any non-null interval i ⊆ [ , ]. we suspect, but have not been able to prove, that ξn has a density fn with respect to lebesgue measure, i.e., ξn is absolutely continuous in the sense that for every ε > there exists δ > such that p[ξn ∈ a] < ε for every a with lebesgue measure less than δ. note that p[ξn ∈ a | xn( )] may be if xn( ) contains non-distinct points: e.g. if n ≥ and xn( ) = (x, x, . . . , x, y), then x ′ n(t) = (x, x, . . . , x) for all t. for a ∈ [ , ], ε > , and t ∈ n, define the event ea,ε(t) := n ⋂ i= {|xi(t) − a| < ε} . the main new ingredient needed to obtain proposition . is the following result. lemma . . let n ≥ . for any ρ ∈ ( , ) and ε > there exist t ∈ n and δ > (depending on n, ρ, and ε) for which, for all a ∈ [ , ], p[ea,ε(t ) | xn( )] > δ (sρ), a.s. proof. fix a ∈ [ , ]. let ρ ∈ ( , ) and ε > . it suffices to suppose that ε ∈ ( , ρ), since ea,ε(t) ⊆ ea,ε′(t) for ε ′ ≥ ε. suppose that sρ occurs, so that mn( ) ≥ ρ with mn( ) defined at ( . ). for ease of notation we list the points of xn ( ) in increasing order as < x < x < · · · < xn < . let m = ⌊n/ ⌋. let ν = ε/n . the following argument shows how one can arrive at a configuration at a finite (deterministic) time t where all of x (t ), . . . , xn(t ) lie inside (a−ε, a+ε) with a positive (though possibly very small) probability. let us call the points which are present at time old points; the points which will gradually replace this set will be called new points. we will first describe an event by which all the old points are removed and replaced by new points arranged approximately equidistantly in the interval [xm, xm+ ], and then we will describe an event by which such a configuration can migrate to the target interval. step . starting from time , iterate the following procedure until a new point becomes an extreme point. the construction is such that at each step, the extreme point is one of the old points, either at the extreme left or right of the configuration. at each step, the extreme old point is removed and replaced by a new u[ , ] point to form the configuration at the next time unit. we describe an event of positive probability by requiring the successive new arrivals to fall in particular intervals, as follows. the first old point removed from the right is replaced by a new point in (xm + ν, xm + ν + δ), where δ ∈ ( , ν) will be specified later. subsequently, the ith point (i ≥ ) removed from the right is replaced by a new point in (xm +iν, xm +iν +δ). we call this subset of new points the accumulation on the left. on the other hand, the ith extreme point removed from the left (i ∈ n) is replaced by a new point in (xm+ −iν, xm+ −iν +δ). this second subset of new points will be called the accumulation on the right. randomized keynesian beauty contest during the first m steps of this procedure, the new points are necessarily internal points of the configuration and so are never removed. therefore, there will be a time t ∈ [m, n] at which, for the first time, one of the new points becomes either the leftmost or rightmost point of xn(t ); suppose that it is the rightmost, since the argument in the other case is analogous. if at time t the accumulation on the right is non-empty, we continue to perform the procedure described in step , but now allowing ourselves to remove new points from the accumulation on the right. so we continue putting extra points on the accumulation on the left whenever the rightmost point is removed, and similarly putting extra points to the accumulation on the right whenever the leftmost point is removed, as described for step . eventually we will have either (a) a configuration where all the new points of the left or the right accumulation are completely removed, and there are still some of the old points left, or (b) a configuration where all old points are removed. the next step we describe separately for these two possibilities. step (a). without loss of generality, suppose that the accumulation on the right is empty, so the configuration consists of k points of the left accumulation and n − k old points remaining to the left of xm (including xm itself). note that step produces at least m new points, so m ≤ k ≤ n − , since by assumption we have at least one old point remaining. let us now denote the points of the configuration x < x < · · · < xn so that xn−k = xm, and by the construction in step , xn−k+i ∈ (xm + iν, xm + iν + δ) for i = , , . . . , k. provided that k ≤ n − , so that there are at least old points, we will show that x is necessarily the extreme point of the configuration. indeed, writing µ = µn(x , . . . , xn), using the fact that xn−k+i ≥ xn−k + iν for ≤ i ≤ k and xn ≤ xn−k + kν + δ, we have µ − x + xn ≥ x + · · · + xn−k + kxn−k + νk(k + ) n − x + xn−k + νk + δ = n ( x + · · · + xn−k + ( k − n)xn−k − nx + νk(k + − n) − δn) . the old points all have separation at least ρ, so for ≤ i ≤ n − k, xi ≥ x + (i − )ρ, and hence x +· · ·+ xn−k +( k−n)xn−k ≥ nx +ρ(n −k− )(n −k)+ρ( k−n)(n −k− ). it follows, after simplification, that µ − x + xn ≥ n (k(n − k − )(ρ − ν) − δn) ≥ n ((n − )(ρ − ν) − δn) , provided ≤ k ≤ n − . by choice of ν, we have ν ≤ ρ/ and it follows that the last displayed expression is positive provided δ is small enough compared to ρ (δ < ρ/ , say). hence |x −µ| > |xn −µ|. thus next we remove x . we replace it similarly to the procedure in step , but now building up the accumulation on the left. we can thus iterate this step, removing old points from the left and building up the accumulation on the left, while keeping the accumulation on the right empty, until we get just one old point remaining (i.e. until k = n − ); this last old point will be xm . at this stage, michael grinfeld, stanislav volkov, andrew r. wade after a finite number of steps, we end up with a configuration where the set of points x < x < · · · < xn satisfies xi ∈ [xm + (i − )ν, xm + (i − )ν + δ], i = , , . . . , n. step (b). suppose that the configuration is such that all old points have been removed but both left and right accumulations are non-empty. repeating the procedure of step , replacing rightmost points by building the left accumulation and leftmost points by building the right accumulation, we will also, in a finite number of steps, obtain a set points xi such that xi ∈ [b + (i − )ν, b + (i − )ν + δ], i = , , . . . , n, for some b ∈ [ , ]. step . now we will show how one can get to the situation where all points lie inside the interval (a − ε, a + ε) starting from any configuration in which xi ∈ [b + iν, b + iν + δ], i = , , . . . , n − , ( . ) where b ∈ [ , ] and x < · · · < xn− are the core points of the configuration (i.e., with the extreme point removed). we have shown in step and step how we can achieve such a configuration in a finite time with a positive probability. suppose that a > b; the argument for the other case is entirely analogous. we describe an event of positive probability by which the entire configuration can be moved to the right. having just removed the extreme point, we stipulate that the new point y belong to (b + nν − δ, b + nν − δ), so y > xn− is the new rightmost point provided δ < ν/ . then to ensure that x , and not y , is the most extreme point we need x + y − [ b + ν n + ] < x + · · · + xn− + y n − [ b + ν n + ] . the left-hand side of the last inequality is less than − δ while the right-hand side is more than − δ n , so the inequality is indeed satisfied provided n ≥ . b + ν ✲✛ δ ✉ b + ν ✲✛ δ ✉ · · · b + (n − )ν ✲✛ δ ✉ b + nν ✛ ✲✛✲ δ δ ✉ figure : schematic of a configuration at the start of step . the disks represent the points x , x , . . . , xn− and, on the extreme right, the new point y . hence at the next step x is removed. our new collection of core points is x < · · · < xn− < y . we stipulate that the next new point y arrive in (b + (n + )ν − δ, b + (n + )ν − δ). so again, for δ small enough (δ < ν/ suffices), y > y and the newly added point (y ) becomes the rightmost point in the configuration. again, to ensure that the leftmost point (x ) is now the extreme one, we require x + y − [ b + ν n + ] < x + · · · + xn− + y + y n − [ b + ν n + ] . the left-hand side of the last inequality is less than − δ, while the right-hand side is more than − δ/n, and so the displayed inequality is true provided n ≥ . we will repeat this process until we remove the rightmost core point present at the start of step , namely xn− , located in [b + (n − )ν, b + (n − )ν + δ]. we will randomized keynesian beauty contest demonstrate how we can do this, in succession removing points from the left of the configuration and at each step replacing them by points on the right with careful choice of locations for the new points. we consecutively put new points yk at locations in intervals ∆k := (b + (n − + k)ν − · kδ, b + (n − + k)ν − · kδ + δ), for k = , , . . . , n − . we have just shown that for k = , this procedure will maintain the leftmost point (xk) as the extreme one. let us show that this is true for all ≤ k ≤ n − , by an inductive argument. indeed, suppose that the original points x , x , . . . , xk− have been removed, the successive new points yj are located in ∆j, j = , , . . . , k − , and that the replacement for the most recently removed point xk− is the new point yk. place the new point yk in ∆k. provided δ < ν · k− + , yk > yk− and yk is the rightmost point of the new configuration, while the leftmost point is xk ∈ [b + νk, b + νk + δ]. since n ≥ we have xk + yk ≤ b + [ n − + k ] ν − [ k − ]δ ≤ b + [ n − + k ] ν − ( + + · · · + k)δ n ≤ xk + · · · + xn− + y + · · · + yk n , thus ensuring that the leftmost point xk, and not yk, is the farthest from the centre of mass. thus, provided δ < −nν, say, we proceed to remove all the points xk and end up with a new collection of points x′ , . . . , x ′ n− satisfying the property x′i ∈ [b ′ + iν, b′ + iν + δ′], i = , , . . . , n − , where b′ = b + (n − )ν − δ′ and δ′ := nδ (> · n− δ). thus the situation is similar to the one in ( . ) but with b replaced by b′ > b + ν, so the whole “grid” is shifted to the right. hence, provided δ is small enough, and δ′ and its subsequent analogues remain such that δ′ < −nν, we can repeat the above procedure and move points to the right again, etc., a finite number of times (depending on |b−a|/ν) until the moment when all the new points are indeed in (a − ε, a + ε), and the probability of making all those steps is strictly positive. in particular, we can check that taking δ < − n/νν will suffice. all in all, we have performed a finite number of steps, which can be bounded above in terms of n, ρ, and ε but independently of a, and each of which required a u[ , ] variable to be placed in a small interval (of width less than −nν) and so has positive probability, which can be bounded below in terms of n, ρ, and ε. so overall the desired transformation of the configuration has positive probability depending on n, ρ, and ε, but not on a. this completes the proof of the lemma. proof of proposition . . write µ′(t) := µn− (x ′ n(t)). let i ⊆ [ , ] be a non-null interval. we can (and do) choose a ∈ ( , ) and ε′ > such that i′ := [a−ε′, a+ε′] ⊆ i. also take i′′ := [a − ε, a + ε] ⊂ i′ for ε = ( bc)− n− / ε′, where c is the constant in lemma . and b ≥ is an absolute constant chosen so that ε < ε′/ for all n ≥ . fix ρ ∈ ( , ). it follows from lemma . that, for some δ > and t ∈ n, depending on ε, p[{µ′(t ) ∈ i ′′} ∩ {d(t ) ≤ ε} | xn ( )] ≥ δ (sρ). michael grinfeld, stanislav volkov, andrew r. wade by lemma . , we have that d(t ) ≤ ε implies that f(t ) ≤ nε < (ε′/( bc)) , so that t ≥ νε′/( bc), where ν· is as defined just before lemma . . applying lemma . with this choice of t and with the ε there equal to ε ′/( bc), we obtain, by markov’s inequality, p [ max t≥t |µ′(t) − µ′(t )| ≤ ε ′/ | ft ] ≥ / , a.s. it follows that, given xn( ), the event {µ′(t ) ∈ i ′′} ∩ {d(t ) ≤ ε} ∩ {|ξn − µ ′(t )| ≤ ε ′/ } has probability at least (δ / ) (sρ), and on this event we have |ξn −a| ≤ ε+( ε ′/ ) < ε′, so ξn ∈ i. hence ( . ) follows. for the final statement in the proposition, suppose that xn( ) consists of independ- ent u[ , ] points. in this case mn( ) defined at ( . ) is the minimal spacing in the induced partition of [ , ] into n + segments, which has the same distribution as n+ times a single spacing, and in particular has density f(x) = n(n + )( −(n + )x)n− for x ∈ [ , n+ ] (cf section a). hence for any ρ ∈ [ , n+ ], we have p[sρ] = ( − (n + )ρ)n, which is positive for ρ = n , say. thus taking expectations in ( . ) yields the final statement in the proposition. . . explicit calculations for n = for this section we take n = , the smallest nontrivial example. in this case we can perform some explicit calculations to obtain information about the distribution of ξ . in fact, we work with a slightly modified version of the model, avoiding certain ‘boundary effects’, to ease computation. specifically, we do not use u[ , ] replacements but, given x (t), we take ut+ to be uniform on the interval [min x ′ (t)− d(t), max x ′ (t)+ d(t)]. if this interval is contained in [ , ] for all t, this modification would have no effect on the value of ξ realized (only speeding up the convergence), but the fact that now ut+ might be outside [ , ] does change the model. for this modified model, the argument for theorem . follows through with minor changes, although we essentially reprove the conclusion of theorem . in this case when we prove the following result, which gives an explicit description of the limit distribution. here and subsequently ‘ d =’ denotes equality in distribution. proposition . . let d = and n = and work with the modified version of the process just described. let x ( ) consist of distinct points in [ , ]. write µ := µ (x ′ ( )) and d := d (x ′ ( )). there exists a random ξ := ξ (x ( )) ∈ r such that x ′ (t) a.s. −→ (ξ , ξ ) as t → ∞. the distribution of ξ can be characterized via ξ d = µ + dl, where l is independent of (µ, d), l d = − l, and the distribution of l is determined by the distributional solution to the fixed-point equation l d =          − +u + ul with probability − −u + u l with probability −u + u l with probability +u + ul with probability , ( . ) randomized keynesian beauty contest where e[|l|k] < ∞ for all k, and u ∼ u[ , ]. writing θk := e[l k], we have θk = for odd k, and θ = , θ = , and θ = . in particular, e[ξ ] = e[µ], e[ξ ] = e[µ ] + e[d ], and e[ξ ] = e[µ ] + e[µd ]. ( . ) in the case where x ( ) contains independent u[ , ] points, e[ξ k ] = , , for k = , , respectively. if x ( ) = ( , , ), then e[ξk ] = , , , for k = , , , . we give the proof of proposition . at the end of this section. first we state one consequence of the fixed-point representation ( . ). proposition . . l given by ( . ) has an absolutely continuous distribution. proof. it follows from ( . ) that p [ l = ] = p [ u ( l − ) = ] + p [ u ( l + ) = ] + p [ u ( l − ) = ] + p [ u ( l + ) = ] . the first two terms on the right-hand side of the last display are zero, by an application of the first part of lemma b. with x = u, y = l± / , and a = , . also, since u > a.s., p[u(l ∓ ) = ] = p[l = ± ], and, by symmetry, p[l = / ] = p[l = − / ]. thus we obtain p [ l = ] = p [ l = ] + p [ l = − ] = p [ l = ] . hence p[l = / ] = p[l = − / ] = . each term on the right-hand side of ( . ) is of the form ± + v (l ± ) where v is an absolutely continuous random variable, independent of l (namely u or u/ ). the final statement in lemma b. with the fact that p[l = ± / ] = shows that each such term is absolutely continuous. finally, lemma b. completes the proof. in principle, the characterization ( . ) can be used to recursively determine all the moments e[lk] = θk, and the moments of ξ may then be obtained by expanding e[ξk ] = e[(µ+dl) k]. however, the calculations soon become cumbersome, particularly as µ and d are, typically, not independent: we give some distributional properties of (µ, d) in the case of a uniform random initial condition in appendix a. before giving the proof of proposition . , we comment on some simulations. figure shows histogram estimates for the distribution of ξ for two initial distributions (one deterministic and the other uniform random), and table reports corresponding mo- ment estimates, which may be compared to the theoretical values given in proposition . . in the uniform case, we only computed the first moments analytically, namely, , , as quoted in proposition . ; it is a curiosity that these coincide with the first moments of the u[ , ] distribution. proof of proposition . . let µ′(t) := (x( )(t) + x( )(t)) and d(t) := |x( )(t) − x( )(t)| denote the mean and diameter of the core configuration, repeating our notation from above. consider separately the events that ut+ falls in each of the four intervals [min x ′ (t) − d(t), min x ′ (t)), [min x ′ (t), min x ′ (t) + d(t)), [min x ′ (t) + d(t), max x ′ (t)), [max x ′ (t), max x ′ (t) + d(t)], michael grinfeld, stanislav volkov, andrew r. wade − − . . . . − . . . . . . . . . . . . figure : normalized histograms based on simulations of the modified n = model with fixed {− / , / , } initial condition (left) and i.i.d. u[ , ] initial condition (right). k ± core . . . . − . . u[ , ] . . . . . . table : empirical kth moment values (to decimal places) computed from the simulations in figure . which have probabilities , , , respectively. given (µ′(t), d(t)), we see, for vt+ a u[ , ] variable, independent of (µ′(t), d(t)), (µ′(t + ), d(t + )) =          (µ′(t) − +vt+ d(t), vt+ d(t)) with prob. (µ′(t) − −vt+ d(t), vt+ d(t)) with prob. (µ′(t) + −vt+ d(t), vt+ d(t)) with prob. (µ′(t) + +vt+ d(t), vt+ d(t)) with prob. . ( . ) writing mk(t) = e[d(t) k | x ( )] we obtain from the second coordinates in ( . ) mk(t + ) = e[v kt+ ]mk(t) + −ke[v kt+ ]mk(t), which implies that mk(t) = ( (k + ) ( + −k) )t d( )k. ( . ) for example, m (t) = ( / ) td( ) and m (t) = ( / ) td( ) . next we show that µ′(t) converges. from ( . ), we have that |µ′(t+ )−µ′(t)| ≤ d(t), a.s., so to show that µ′(t) converges, it suffices to show that ∑∞ t= d(t) < ∞ a.s. but this can be seen from essentially the same argument as lemma . , or directly from the fact that the sum has nonnegative terms and e ∑∞ t= d(t) = ∑∞ t= e[m (t)], which is finite. hence µ′(t) converges a.s. to some limit, ξ say. extending this argument a randomized keynesian beauty contest little, we have from ( . ) that |µ′(t+ )| ≤ |µ′(t)|+d(t), a.s., and d(t+ ) ≤ vt+ d(t), a.s. hence for v , v , . . . i.i.d. u[ , ] random variables, we have d(t) ≤ v · · · vtd( ) and |µ′(t)| − |µ′( )| = t− ∑ s= (|µ′(s + )| − |µ′(s)|) ≤ ( + ∞ ∑ s= s ∏ r= vr ) d( ) =: ( + z)d( ). here z has the so-called dickman distribution (see e.g. [ , § ]), which has finite moments of all orders. hence e[|µ′(t)|p | x ( )] is bounded independently of t, so, for any p ≥ , (µ′(t))p is uniformly integrable, and hence limt→∞ e[(µ ′(t))k | x ( )] = e[ξk | x ( )] for any k ∈ n. we now want to compute the moments of ξ ; by the previous argument, we can first work with the moments of µ′(t). note that, from ( . ), e[(µ′(t + ) − µ′(t))k | x (t)] = + (− )k d(t)ke [ ( + vt+ )k ] + + (− )k d(t)ke [ ( + vt+ )k ] = + (− )k ( −k + − k) k+ − k + d(t)k, using the fact that e[( +vt+ ) k] = k+ − k+ . in particular, e[(µ′(t+ )−µ′(t))k | x (t)] = for odd k, so e[µ′(t) | x ( )] = µ ′( ), and hence e[ξ ] = limt→∞ e[µ ′(t)] = e[µ′( )], giving the first statement in ( . ). in addition, e[(µ′(t + )) − (µ′(t)) | x (t)] = µ′(t)e[µ′(t + ) − µ′(t) | x (t)] + e[(µ ′(t + ) − µ′(t)) | x (t)] = d(t) . hence e[(µ′(t)) − (µ′( )) | x ( )] = t− ∑ s= e[(µ′(s + )) − (µ′(s)) | x ( )] = t− ∑ s= m (s) → ∞ ∑ s= −sd( ) , as t → ∞, and the limit evaluates to d( ) , so that e[ξ ] = limt→∞ e[(µ ′(t)) ] = e[(µ′( )) ] + e[d( ) ], giving the second statement in ( . ). write l(µ′( ), d( )) = ξ (x ( )) emphasizing the dependence on the initial config- uration through µ′( ) and d( ). then by translation and scaling properties l(µ′( ), d( )) d = µ′( ) + d( )l( , ). ( . ) so we work with l := l( , ) (which has the initial core points at ± ). michael grinfeld, stanislav volkov, andrew r. wade we will derive a fixed-point equation for l. the argument is closely related to that for ( . ). conditioning on the first replacement and using the transformation relation ( . ), we obtain ( . ). from ( . ) we see that |l| is stochastically dominated by + u|l|; iterating this, similarly to the argument involving the dickman distribution above, we obtain that |l| is stochastically dominated by + z, where z has the dickman distribution, which is determined by its moments. hence ( . ) determines a unique distribution for l with e[|l|k] < ∞ for all k. writing ( . ) in functional form l d = Ψ(l), we see that by symmetry of the form of Ψ, also Ψ(l) d = − Ψ(−l). hence −l d = − Ψ(l) d = Ψ(−l), so −l satisfies the same distributional fixed-point equation as does l. hence l d = − l. writing θk := e[l k], which we know is finite, we get θk = k ∑ j= ( k j ) ( + (− ))jθk−je [ ( + u )j uk−j ] + k ∑ j= ( k j ) ( + (− ))jθk−je [ ( − u )j ( u )k−j ] . here e [ ( + u )j uk−j ] = −j j ∑ ℓ= ( j ℓ ) k − ℓ + =: a(k, j); e [ ( − u )j ( u )k−j ] = −k j ∑ ℓ= ( j ℓ ) (− / )j−ℓ k − ℓ + =: b(k, j). so we get θk = ∑ j even, j≤k ( k j ) θk−j( a(k, j) + b(k, j)). ( . ) in particular, as can be seen either directly by symmetry or by an inductive argument using ( . ), θk = for odd k. for even k, one can use ( . ) recursively to find θk, obtaining for example the values quoted in the proposition. note that, by ( . ), e[ξ ] = e[(µ ′( ) + ld( )) ], which, on expansion, gives the final statement in ( . ). the first moments in the case of the uniform initial condition follow from ( . ) and lemma a. . for the initial condition with points , , , we have d( ) = and µ′( ) = χ +( −χ) = − χ , where χ is the tie-breaker random variable taking values or each with probability . it follows that e[µ′( )k] = −k( k + k). then, using ( . ), e[ξk ] = e[(µ ′( ) + (l/ ))k] = −k k ∑ j= ( k j ) jθj( k−j + k−j). we can now compute the four moments given in the proposition. randomized keynesian beauty contest appendix a. uniform spacings in this appendix we collect some results about uniform spacings which allow us to obtain distributional results about our uniform initial configurations. the basic results that we build on here can be found in section . of [ ]; see the references therein for a fuller treatment of the theory of spacings. let u , u , . . . , un be independent u[ , ] points. denote the corresponding in- creasing order statistics u[ ] ≤ · · · ≤ u[n], and define the induced spacings by sn,i := u[i] −u[i− ], i = , . . . , n+ , with the conventions u[ ] := and u[n+ ] := . we collect some basic facts about the sn,i. the spacings are exchangeable, and any n-vector, such as (sn, , . . . , sn,n), has the uniform density on the simplex ∆n := {(x , . . . , xn) ∈ [ , ]n : ∑n i= xi ≤ }. we need some joint properties of up to spacings. any spacings have density f(x , x , x ) = n(n − )(n − )( − x − x − x ) n− on ∆ . we note that min{sn, , sn, } d = sn, , (n ≥ ), (a. ) (sn, , min{sn, , sn, }) d = (sn, , sn, ), (n ≥ ); (a. ) see for example lemma . of [ ]. finally, for any n ≥ and α ≥ , β ≥ , e[sαn, s β n, ] = Γ(n + )Γ(α + )Γ(β + ) Γ(n + + α + β) . (a. ) in particular e[skn, ] = n!k! (n+k)! for k ∈ n. our main application in the present paper of the results on spacings collected above is to obtain the following result, which we use in section . . lemma a. . let d = and n = . suppose that x ( ) consists of independent u[ , ] points. then (µ (x ′ ( )), d (x ′ ( ))) d = ((s + s )ζ + ( − s − s )( − ζ), s ), where ζ is a bernoulli random variable with p[ζ = ] = p[ζ = ] = / . for k ∈ z+, e[(d (x ′ ( ))) k] = −k (k + )(k + )(k + ) , (a. ) e[(µ (x ′ ( ))) k] = ( k − + ( k+ − ) −(k+ )) (k + )(k + )(k + ) . (a. ) so, for example, the first moments of d (x ′ ( )) are , , and , while the first moments of µ (x ′ ( )) are , , and . finally, e[µ (x ′ ( ))(d (x ′ ( ))) ] = . proof. the points of x ( ) induce a partition of the interval [ , ] into uniform spacings s , s , s , s , enumerated left to right (for this proof we suppress the first index in the notation above). for ease of notation, write d := d (x ′ ( )) and µ := µ (x ′ ( )) for the duration of this proof. then d = min{s , s } d = s / , by (a. ). moreover, min{s , s } is equally likely to be either s or s . in the former case, michael grinfeld, stanislav volkov, andrew r. wade µ = s + min{s , s }, while in the latter case µ = − s − min{s , s }. using (a. ), we obtain the following characterization of the joint distribution of µ and d. (µ, d) d = { (s + s , s ) with probability ( − s − s , s ) with probability . (a. ) hence e[dk] = −ke[sk ], which gives (a. ) by the n = , α = k, β = case of (a. ). for the moments of µ, we have from (a. ) that µ has the distribution of w := s + s with probability / or − w with probability / . so we have e[µk] = e[w k] + e[( − w)k] = wk + k ∑ j= ( k j ) (− )jwj, where wk := e[w k]. since wk = e[(s + s ) k], we compute wk = k ∑ j= ( k j ) −je[s k−j s j ] = k! (k + )! k ∑ j= −j, by the n = , α = k − j, β = j, case of (a. ). thus we obtain wk = ( − −(k+ )) (k + )(k + )(k + ) . it follows that e[µk] = wk + k ∑ j= k! (j + )!(k − j)! (− )j − k ∑ j= k! (j + )!(k − j)! (− / )j. we deduce (a. ), after simplification, from the claim that, for any z ∈ r, s(z) := k ∑ j= k! (j + )!(k − j)! (−z)j = k! z (k + )! [ z (k + )(k + ) + − z(k + ) − ( − z)k+ ] . (a. ) thus it remains to verify (a. ). to this end, note that s(z) = k! (k + )! k ∑ j= ( k + j + ) (−z)j = k! (k + )!  −z− k+ ∑ j= ( k + j ) (−z)j + z− ( k + ) − z− ( k + ) + z− ( k + )   = k! z (k + )! [ −( − z)k+ + z (k + )(k + ) − z(k + ) + ] , which gives the claim (a. ). randomized keynesian beauty contest for the final statement in the lemma, we have from (a. ) that e[µd ] = e[(s + s )( s )] + e[( − s − s )( s )] = e[s ] = , by (a. ). this completes the proof of the lemma. we can also obtain explicit expressions for the densities of d and µ. since d d = s / , the density of d is fd(r) = ( − r) for r ∈ [ , / ]. in addition, µ has density fµ given by fµ(r) =      r[ ( − r) − r] if r ∈ [ , / ] − r( − r) if r ∈ [ / , / ] ( − r)[ r − ( − r)] if r ∈ [ / , ] . (a. ) indeed, with the representation of µ as either w or −w with probability / of each, we have p[µ ≤ r] = p[w ≤ r] + ( − p[w < − r]). assuming that w has a density fw (which indeed it has, as we will show below), we get fµ(r) = fw (r) + fw ( − r). (a. ) using the fact that w d = s + s , we use the joint distribution of (s , s ) to calculate p[w ≤ r] = ∫ dx ∫ −x dx ( − x − x ) {x + x ≤ r} = ∫ r dx ∫ ( (r−x ))∧( −x ) dx ( − x − x ). after some routine calculation, we then obtain p[w ≤ r] = { − ( − r) + ( − r) if r ∈ [ , / ] − ( − r) if r ∈ [ / , ]. hence w has density fw given by fw (r) = { ( − r) − ( − r) if r ∈ [ , / ] ( − r) if r ∈ [ / , ]. then (a. ) follows from (a. ). appendix b. continuity of random variables in this appendix we give some results that will allow us to deduce the absolute continuity of certain distributions specified as solutions to fixed-point equations: spe- cifically, we use these results in the proof of proposition . . the results in this section may well be known, but we were unable to find a reference for them in a form directly suitable for our application, and so we include the (short) proofs. lemma b. . let x and y be independent random variables such that x has an absolutely continuous distribution. then for any a = we have p[xy = a] = . moreover, if p[y = ] = , then xy is an absolutely continuous random variable. michael grinfeld, stanislav volkov, andrew r. wade proof. for the moment assume that p[x < ], p[x > ], p[y < ], and p[y > ] are all positive. take some < c < d. then p[xy ∈ (c, d)] = p[log(x) + log(y ) ∈ (log c, log d) | x > , y > ]p[x > ]p[y > ] +p[log(−x) + log(−y ) ∈ (log c, log d) | x < , y < ]p[x < ]p[y < ]. note that conditioning x on the event x > (or x < ) preserves the continuity of x and the independence of x and y . then since the sum of two independent random variables at least one of which absolutely continuous is also absolutely continuous (see [ , theorem . , p. ]) we have p[log(x) + log(y ) ∈ (log c, log d) | x > , y > ] = ∫ log d log c f+(x)dx, and p[log(−x) + log(−y ) ∈ (log c, log d) | x < , y < ] = ∫ log d log c f−(x)dx, for suitable probability densities f+ and f−. after the substitution u = e x, this yields p[xy ∈ (c, d)] = ∫ d c p[x > ]p[y > ]f+(log u) + p[x < ]p[y < ]f−(log u) u du. this expression is also valid if some of the probabilities for x and y in the numerator of the integrand are zero. therefore, we have, for any < c < d, p[xy ∈ (c, d)] = ∫ d c f(u)du, (b. ) for some function f(u) defined for u > . a similar argument applies to the case c < d < ; then (b. ) is valid for any c < d < as well, extending f(u) for strictly negative u. in particular, it follows that p[xy = a] = for a = . now if p[y = ] = , then p[xy = ] = . then we can set f( ) = so that (b. ) holds for all c, d ∈ r. this completes the proof. lemma b. . suppose that a random variable l satisfies the distributional equation l d =        z with probability p ... zn with probability pn, where n ∈ n, ∑n i= pi = , pi > , and each zi is an absolutely continuous random variable. then l is absolutely continuous. proof. suppose zi has a density fi. then for any −∞ ≤ a < b ≤ +∞ we have p[l ∈ (a, b)] = n ∑ i= pip[zi ∈ (a, b)] = n ∑ i= pi ∫ b a fi(x)dx = ∫ b a [ n ∑ i= pifi(x) ] dx, which yields the statement of lemma. randomized keynesian beauty contest acknowledgements parts of this work were done at the university of strathclyde, where the third author was also employed, during a couple of visits by the second author, who is grateful for the hospitatlity of that institution. references [ ] benassi, c. and malagoli, f. the sum of squared distances under a diameter constraint, in arbitrary dimension. arch. math. 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[ ] moulin, h. game theory for the social sciences, nd ed., new york university press, new york, . [ ] muratov, a. and zuyev, s. lisa: locally interacting sequential adsorption, stoch. models ( ) – . [ ] pemantle, r. a survey of random processes with reinforcement. probab. surv. ( ) – . [ ] penrose, m.d. and wade, a.r. random minimal directed spanning trees and dickman-type distributions. adv. in appl. probab. ( ) – . [ ] penrose, m.d. and wade, a.r. limit theory for the random on-line nearest-neighbor graph. random structures algorithms ( ) – . [ ] pillichshammer, f. on the sum of squared distances in the euclidean plane. arch. math. ( ) – . [ ] witsenhausen, h.s. on the maximum of the sum of squared distances under a diameter constraint. amer. math. monthly ( ) – . pii: s - ( ) - b o o k r e v i e w g lorious s y m m e t r y david w a d e address: w a k s m a n institute, rutgers university, piscataway, n j , u s a . chemistry & biology m a r c h , : current biology ltd i s s n - t h e most beautiful molecule: t h e discovery of the buckybdl by h u g h aldersey-williams, john wiley & sons, inc. n e w york, . pp. $ . (hardcover) i s b n - - -x prior to , it w a s thought that the only forms of pure carbon that occurred in nature were diamond and graphite. however, during experiments on the mecha- nisms of formation of long chain carbon molecules in interstellar space and near stars, chemists richard smalley, of rice university, and harry kroto, of the uni- versity of sussex, discovered a remarkably stable cluster of carbons. t h e cluster w a s found to be c o m p o s e d of a single molecule containing carbon atoms, c,,, and it had a highly symmetric, cage-like, spherical structure resembling the surface of a soccerball. carbons formed the vertices, and covalent bonds between the carbons formed the edges, of a polyhedron containing faces: hexagons and pentagons. t h e molecule w a s n a m e d ‘buckminsterfullerene’ in honor of the architect, richard buckminster fuller, w h o popularized geodesic domes. subsequent work by physicists wolfgang kdtschmer, of the max-planck-institute of nuclear physics, and donald huffman, of the university of arizona, led to the development in of a method to produce macroscopic quantities of c,,, thereby facilitat- ing the extensive investigations into its chemistry and applications that are currently in progress. t h e discov- ery of a third allotrope of carbon has created what is effectively a n e w sub-discipline within chemistry. those w h o study c,, and its derivatives promise theoretical advances and practical applications in diverse areas, such as lubricants, superconductors, ferromagnets, catalysts and h i v protease inhibitors. t h e most beaut$idmozecu/e describes the discovery of c,,, and also the subsequent developments that led to verili- cation of its structure and properties. t h e author suc- cessfully conveys the excitement that accompanies a major scientific discovery, in a style that is reminiscent of j i m watson’s classic, t h e d o & e helix (although in this case the author w a s not involved in the events described) and for this reason alone the book is worth reading. t h e book is well written, with illustrations, pages of collected footnotes and an index. t h e book appears to be intended for a general audience, but will be best appreciated by those w h o are familiar with a few basic concepts and techniques from organic chemistry. t h e author touches on m a n y technical aspects associated with the field, including: molecular structure; atomic and molecular orbitals, and molecular orbital theory; sigma and pi bonding; hybridization; symmetry; chirality; single, double and triple bonds; conjugation; resonance; aromaticity; angle strain; chromatography; spectroscopy (uv, ir, and n m r ) ; x-ray diffraction; host-guest complexes; organometallic complexes; photo- chemistry and superconductivity. this book might be more useful if available in a less expensive paperback edition; it could then be a useful teaching aid for science courses, to be read in conjunc- tion with the original paper by kroto, smalley and coworkers on the discovery of c, (nature ( ) , - ), which is covered in detail in the book; krptschmer, huffman and colleagues’ paper on the syn- thesis of macroscopic quantities of c,, (nature ( ) , - ); and a review article on the fullerenes (accounts c h e m . res. ( ) , - ). t h e publication of this book coincides with a p b s television broadcast of a n o v a documentary about the discovery of c,,; video cassette tapes of the program are also available from: films for the humanities and sciences, b o x , princeton, n j - , u s a , phone: . core metadata, citation and similar papers at core.ac.uk p r o v i d e d b y e l s e v i e r - p u b l i s h e r c o n n e c t o r https://core.ac.uk/display/ ?utm_source=pdf&utm_medium=banner&utm_campaign=pdf-decoration-v pbio. .. neuroaesthetics and the trouble with beauty the harvard community has made this article openly available. please share how this access benefits you. your story matters citation conway, bevil r., and alexander rehding. . neuroaesthetics and the trouble with beauty. plos biology ( ): e . published version doi: . /journal.pbio. citable link http://nrs.harvard.edu/urn- :hul.instrepos: terms of use this article was downloaded from harvard university’s dash repository, and is made available under the terms and conditions applicable to other posted material, as set forth at http:// nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of- use#laa http://osc.hul.harvard.edu/dash/open-access-feedback?handle=&title=neuroaesthetics% and% the% trouble% with% beauty&community= / &collection= / &owningcollection / &harvardauthors= e adc d c a eab cdbe fae&departmentmusic http://nrs.harvard.edu/urn- :hul.instrepos: http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa essay neuroaesthetics and the trouble with beauty bevil r. conway , *, alexander rehding program in neuroscience, wellesley college, wellesley, massachusetts, united states of america, department of neurobiology, harvard medical school, boston, massachusetts, united states of america, department of music, harvard university, cambridge, massachusetts, united states of america the famous nineteenth-century psycho- physicist gustav fechner was also a poet and art critic. armed with the tools of science, fechner sought to reconcile his various interests. he would doubtless be interested by technological developments in neuroscience that have revealed the operations of neurons at cellular resolution and have enabled us to peer almost unnoticed into each other’s working brains. but can these tools advance our understanding of aesthetics beyond fech- ner’s insights [ ]? the nascent field of neuroaesthetics claims it can. here we consider what questions this new field is poised to answer. we underscore the importance of distinguishing between beauty, art, and perception—terms often conflated by ‘‘aesthetics’’—and identify adjacent fields of neuroscience such as sensation, perception, attention, reward, learning, memory, emotions, and decision making, where discoveries will likely be informative. aesthetics and neuroscience aesthetics has a complex history. the term derives from the greek ‘‘perception’’ and was coined by alexander baumgarten in as the study of sensory knowledge. but following immanuel kant’s critique of judgment in [ ], aesthetics began focusing on the concept of beauty, in nature and in art. during the nineteenth century, the term became largely synony- mous with the philosophy of art. these three connotations—perception, beauty, art—point in different directions but are often conflated in neuroaesthetics. kant is a preferred philosopher among neuroaestheticians, no doubt because of his towering stature in the history of western thought. he pursued a universal- ist approach to beauty, an appealing concept for neuroscientists because it suggests a discrete neural basis. but kant’s concept of beauty has been severely criticized in light of the prevailing plural- ism of artistic styles. to make matters more complicated, there is no consensus on the nature of beauty. kant’s under- standing of beauty was predicated on an attitude of ‘‘disinterested contemplation’’ [ ], whereas friedrich nietzsche roundly dismissed this notion and underlined the impact of sensual attraction [ ]. for the poet john keats, beauty equaled truth [ ], while stendhal, the french novelist, char- acterized beauty as the ‘‘promise of happiness’’ [ ]. more recently, elaine scarry described beauty as an urge to repeat [ ]. while each of these theories is respected, not one is universally accepted. partly this diversity of opinions is connect- ed to the different functions that beauty holds within various philosophical systems, being sometimes viewed in connection with epistemology or with ethics. one goal of neuroaesthetics is to get to the bottom of the problem of artistic beauty. how can this be accomplished? experiences of beauty are often deeply moving, and their importance to the human condition invites a neuroscientific explanation. but while deep emotional reactions are often associated with beauty, being moved does not always indicate an instance of beauty. consider hearing about a disaster, celebrating a sports victory, or smelling a long-forgotten scent. these experiences are better described as ‘‘sympathy,’’ ‘‘elation,’’ and ‘‘memory,’’ rather than experiences of beauty. if neuroaesthetics is to be concerned specif- ically with beauty, it must draw distinc- tions between mechanisms for such dispa- rate reactions. since many experiences of beauty are related to art, neuroaestheti- cians have focused their attention on the analysis of artworks. for example, rama- chanran [ ], zeki [ ], and kandel [ ] have presented case studies focusing on classical indian art, american and euro- pean modernists, and the viennese seces- sionists. explicitly or implicitly, these studies aim to extract rules that would lead to a practical definition of beauty, connecting features of objects and neural activity. zeki, for instance, argues that the power of alexander calder’s sculptures derives from the black-and-white moving parts, potent activators of the brain’s motion-processing center. it may be no coincidence that the art these three authors hold up relates to the culture in which they were each raised. one potential danger in aesthetic projects is to universalize one’s subjective convic- tions and assume that an experience of beauty is common to all. projecting from individual subjective experience is decep- tive, for there is ample evidence that notions of beauty vary between cultures and are mutable even within a culture— just think of fast-changing trends in fashion. moreover, the equation (art = beauty) rests on shaky ground. throughout history, artists have created deeply moving art- work that is emphatically not beautiful; goya’s saturn devouring one of his sons (figure ) provides a famous historical example. large swaths of twentieth- century art have greatly expanded—or entirely disavowed—notions of beauty. such distinctions may seem picky, but interdisciplinary work such as neuroaes- thetics relies on shared principles, and requires heightened attention to concep- tual clarity. essays articulate a specific perspective on a topic of broad interest to scientists. citation: conway br, rehding a ( ) neuroaesthetics and the trouble with beauty. plos biol ( ): e . doi: . /journal.pbio. published march , copyright: � conway, rehding. this is an open-access article distributed under the terms of the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. funding: this work was supported by the national science foundation (grant ). the nsf had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. competing interests: the authors have declared that no competing interests exist. * e-mail: bconway@wellesley.edu plos biology | www.plosbiology.org march | volume | issue | e neuroscience has provided a heuristic outlining how sensory signals are pro- cessed by the nervous system to yield behavior [ , ]. signals from sensory epithelia such as the retina or basilar membrane are processed in the cerebral cortex by a series of areas that compute descriptions of the world: what or where objects are. these brain areas send signals to other brain structures that are respon- sible for evaluating options against expect- ed rewards—attaching significance to the sensory descriptions—and ultimately for making decisions, guided by learning, memory, and emotions. below we argue that a successful neuroaesthetics will include the study of each of these stages of processing as they relate to handling, encoding, and generating aesthetic expe- riences, rather than an attempt to derive a single universal neural underpinning of what constitutes beauty. first steps in neuroaesthetics: sensation, perception, and art one approach commonly included under the umbrella of neuroaesthetics involves examining art objects in muse- ums. here the complication of establishing ‘‘beauty’’ is obviated by treating artworks as products of a massive empirical exper- iment. by analogy with evolutionary theory, the assumption is that the tiny number of works that survive the selective pressures exerted by collectors, cultural institutions, and fads are enriched for the strength of their effects on the nervous system. using this approach, studies have uncovered various artistic strategies re- flecting fundamental operations of the neural mechanisms for sensation and perception [ , , – ]. for example, de- pictions of shadows in paintings often do not correspond to the light sources that cause them [ ]. such unnoticed devia- tions from veracity reveal important ad- aptations of the brain to ecological pres- sures during evolution and development— in the case of shadows, the relationship of objects to light sources is in flux and therefore not a stable feature. similarly, analysis of portraits has been insightful, showing that the outer contour of a face is more important for face recognition than the precise configuration of features [ ]. and paintings by paul cezanne, henri matisse, and claude monet show how these artists capitalized upon the neural mechanisms of color [ ]. this line of research is often described as the neuro- science of art, rather than neuroaesthetics, since it does not test for beauty [ ]. the approach may reveal the perceptually figure . goya y lucientes, francisco de, saturn devouring one of his sons ( – ). mural transferred to canvas. . cm . cm. museo del prado, madrid. doi: . /journal.pbio. .g plos biology | www.plosbiology.org march | volume | issue | e relevant properties of visual stimuli— contributing to aesthetics as baumgarten defined it—but these properties are nei- ther necessary nor sufficient features of beautiful objects. an alexander calder sculpture may consist of optimal stimuli for the brain’s motion center, but this aspect of the work does not make it beautiful. the art simply provides a fascinating demonstration of the compu- tations of the brain’s motion-perception circuits, and the genius of the artists for discovering them. it is an open question whether an analysis of artworks, no matter how celebrated, will yield universal principles of beauty. compositional principles such as the golden ratio are intriguing possible universals, and captured the attention of fechner, but despite mathematical appeal, the golden rectangle is not the favorite rectangle shape of most people [ ]. one possible almost-universal may be the appeal of certain female facial features (symmetry, high cheekbones, large eyes) and a . waist-to-hip ratio [ ] or high body mass index [ ]. explanations for these preferences depend on a correlation between the attributes and reproductive fitness. yet celebrated representations of female beauty across history can deviate considerably from the . rule, and ratio preferences vary across cultures [ , ]. depictions of reproductive fitness can be sexually appealing and contribute to aesthetic appeal, but such depictions are, again, neither necessary nor sufficient for beauty. another possible universal con- cerns the intriguing discovery that painters typically center one eye along the hori- zontal axis of a picture [ ], taken to indicate ‘‘hidden principles…operating in our aesthetic judgments.’’ but the trend towards eye-centering has declined dra- matically during and after avant-garde movements such as those led by picasso [ ]. whether this decline is attributable to the relative decline of beauty as a driving force in artistic creation or indi- cates a cultural shift in aesthetic prefer- ences is unclear. using celebrated works as empirical data to understand beauty might be a worthwhile gambit, but we doubt that conclusions can be extended across peo- ples, times, and cultures. the only univer- sal feature of beauty besides our capacity to experience it appears to be its mutabil- ity, itself perhaps a topic for neuroscience. a beauty center? fechner was well aware of the pitfalls of philosophical aesthetics and aimed to reformulate the field ‘‘from the ground up.’’ his appreciation of the inherently subjective nature of beauty led him to start with feelings of pleasure and displeasure elicited by art, since these constituted for him the bottom line beyond which further analysis was impossible. contemporary neuroscience has gone much further. a recent study claims that ‘‘all works that appear beautiful to a subject have a single brain-based characteristic, which is that they have as a correlate of experiencing them a change in strength of [fmri] activity within the mofc [medial orbito- frontal cortex]’’ [ ]. leaving aside meth- odological challenges [ , ], is such a correlation meaningful to understanding aesthetics? subjectivist studies such as these over- come the difficulty of defining beauty by asking the participants to first rate visual objects or sounds [ , ]. brain activity of each subject is then assessed to their own set of ‘‘beautiful’’ versus ‘‘ugly’’ stimuli. four experimental-design chal- lenges surface. first, the options are necessarily restricted, and might not in- clude a truly beautiful choice—the study design tests preferences, not beauty. second, different subjects likely interpret the instructions in radically different ways. third, the use of different stimulus sets in different subjects makes it difficult to control for differences in low-level stimu- lus features, which likely drive different patterns of neural activity. and fourth, the experiment requires that a given object retain a fixed preferred status, and one that is not modulated by context, which we know is unlikely. as fechner showed, mere exposure changes judg- ments of preference in favor of the familiar option. brandishing fmri does not circumvent these problems. more- over, fmri has cripplingly low spatial and temporal resolution, and the relationship between the measured signal and under- lying neural activity is indirect. in addi- tion, fmri experiments often only report regions that show differential activation between pairs of conditions (e.g., response to beautiful greater than response to ugly); such an analysis is misleading in situations in which all brain regions show significant but slightly different levels of activity for the different conditions, as is likely the case in considerations of beauty. brain imaging provides a blurry, although seductively glossy, view of brain function. and by finessing a definition of beauty, these sorts of studies sidestep what is at the heart of our interest in beauty: the connection between physical stimuli, spe- cifically those crafted by human hands, and our response. nonetheless, a discovery that every person’s experience of beauty (however vaguely defined) correlates with activity within a specific brain region would be surprising, since it would seem more likely that a complex reaction (beautiful!) would hinge not on the absolute level of activity within a single brain center but rather on the pattern of activity across many distrib- uted brain regions—specifically those re- sponsible for perception, reward, decision making, and emotion. indeed, a broader reading of the literature reveals that the mofc is not uniquely associated with experiences of beauty and may be neither necessary nor sufficient for these experi- ences. the mofc appears to be part of a large network of brain regions that sub- serves all value judgments. for example, elevated activity within the mofc is reported in studies of neuroeconomics in which subjects are asked to assign value to a selection of choices and are never asked to consider the beauty of the choices [ , – ]. the mofc has also been implicated in impulse control and self- regulation [ ], in changing decision thresholds that influence whether infor- mation should be expressed in an evalu- ation [ ], in attentional processes that underlie emotion-congruent judgment [ ], and in moral decision making [ ]. ascribing responses of the mofc to experiences of beauty is premature; many experiences depend on these processes without being beautiful [ , – ]. if the mofc plays a critical role in mediating beauty, one might expect that strokes of the region would impair expe- riences of beauty. strokes of the mofc are rare, but the limited evidence suggests they affect self-related systems such as self- evaluation [ , ] and do not impact a person’s ability to experience beauty. alternatively, strokes in other brain re- gions can, paradoxically, enhance creativ- ity, providing support for the notion that the expression of beauty depends on a broad, distributed network. frontotempo- ral dementia can produce an acquired obsessiveness that is often linked to enhanced art production, usually of ex- tremely detailed works [ ]. in addition, strokes of the left hemisphere, which often cause aphasia, can produce hyperexpres- siveness [ ]. what questions can neuroaesthetics answer? inspired by the power of polling, in a pair of artists, komar and melamid, set out to determine ‘‘usa’s most wanted painting.’’ the painting was formulated on plos biology | www.plosbiology.org march | volume | issue | e the basis of a thousand people’s responses to questions of their favorite color, favorite setting, and favorite subjects. the resulting painting is absurd, showing that a compo- sition with everything that people find beautiful does not make a beautiful paint- ing. rational reductionist approaches to the neural basis for beauty run a similar risk of pushing the round block of beauty into the square hole of science and may well distill out the very thing one wants to understand. there is a popular conception of beauty as a fixed attribute of objects, a notion that much of current neuroaes- thetics depends upon. but there is a distinction between abstract notions of beauty and our experience of it—consider a specific example in which you have experienced beauty. beauty is an analog, not binary, condition that varies in complex ways with exposure, context, attention, and rest—as do most perceptual responses. in trying to crack the subjective beauty nut with scientific, objective information, we also run the risk of fueling a normative, possibly dangerous campaign through which science is required to valorize our experience. should we deny someone’s experience of beauty if the mofc is not activated? obviously not. but the question underscores the danger of reverse infer- ence, a technique used in brain-imaging studies which posits that activation of a brain region indicates the presence of a stimulus [ ]. reverse inference is almost always invalid because single brain struc- tures almost never regulate single specific experiences. insofar as beauty is a product of the brain, correlations between brain activity and experiences of beauty must exist. at what spatial scale, and within what brain regions, do we find these correlations? what functions do the brain regions implicated serve in other behaviors? what signals during development and experi- ence are responsible for wiring up these circuits? and perhaps most critically, how does the activity of these circuits integrate across modalities and time to bring about the dynamic, elusive quality of beauty? to address these questions, the field is thirsty for carefully conducted experiments that distinguish responses to beauty from those involved in more general value-based decision tasks such as self-evaluation or selecting a juice for lunch. but any such experiments are caught on the same stubborn thorn—the lack of a cogent, universally accepted definition of beauty. one should not always demand a precise definition to make headway, but it might turn out that the philosophers’ disagree- ment is symptomatic: maybe there is no universal concept beyond the human capacity to experience beauty. our cau- tion about neuroscience’s focus on beauty differs from the skepticism that attended scientific study of other subjective phe- nomena such as illusory contours (or even consciousness); in the case of illusory contours, the subjective experience to a given physical stimulus is universal. so, what is neuroaesthetics supposed to study? experiences of beauty typically require attention and are accompanied by feelings of pleasure [ , , ]. in the same way that basic studies at the interface of sensory neuroscience and art have been productive—not in addressing why art objects are beautiful but in uncovering the strategies that artists use to generate artwork—basic investigations of the mech- anisms of attention, decision making, reward, and emotion [ , , , – ] could inform neuroaesthetics. the field will benefit from developing models relat- ing observations from the humanities to the careful neuroscience that has uncov- ered computations at cellular resolution within the value-judging structures of the monkey brain. these structures, not coincidentally, are analogous to those identified in fmri studies of beauty in humans. some neurons within these structures encode the value of the choices on offer, while others encode the value of the selected choice. moreover, the neurons adapt on different timescales, displaying ‘‘menu-invariant’’ firing at short timescales and adaptable behavior on longer time- scales. this adaptation may account for our ability to make choices across vastly different scales, for example from a restaurant menu in one instance and from houses offered for sale in the next instance [ ]. it seems entirely reasonable—even likely—that these neurons are also impli- cated in the thorny task of deciding what is beautiful. reformulated in this way, neu- roaesthetics is decoupled from beauty and can exploit advances across a range of empirical neuroscience, from sensory en- coding to decision making and reward. there may well be a ‘‘beauty instinct’’ implemented by dedicated neural machin- ery capable of producing a diversity of beauty reactions, much as there is lan- guage circuitry that can support a multi- tude of languages (and other operations). a need to experience beauty may be universal, but the manifestation of what constitutes beauty certainly is not. on the one hand, a neuroaesthetics that extrapo- lates from an analysis of a few great works, or one that generalizes from a single specific instance of beauty, runs the risk of missing the mark. on the other, a neuroaesthetics comprising entirely sub- jectivist accounts may lose sight of what is specific to encounters with art. neuroaes- thetics has a great deal to offer the scientific community and general public. its progress in uncovering a beauty instinct, if it exists, may be accelerated if the field were to abandon a pursuit of beauty per se and focus instead on uncovering the relevant mechanisms of decision making and reward and the basis for subjective preferences, 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( ) emergence of artistic talent in frontotemporal dementia. neurology : – . . chatterjee a ( ) the neuropsychology of visual artistic production. neuropsychologia : – . . poldrack ra ( ) can cognitive processes be inferred from neuroimaging data? trends cogn sci : – . . vartanian o, goel v ( ) neuroanatomical correlates of aesthetic preference for paintings. neuroreport : – . . schultz w ( ) potential vulnerabilities of neuronal reward, risk, and decision mechanisms to addictive drugs. neuron : – . . schultz w, o’neill m, tobler pn, kobayashi s ( ) neuronal signals for reward risk in frontal cortex. ann n y acad sci : – . . shenhav a, greene jd ( ) moral judgments recruit domain-general valuation mechanisms to integrate representations of probability and mag- nitude. neuron : – . . padoa-schioppa c ( ) range-adapting repre- sentation of economic value in the orbitofrontal cortex. j neurosci : – . plos biology | www.plosbiology.org march | volume | issue | e sleeping beauties in psychology yuh-shan ho and james hartley trend research centre, asia university, taiwan and school of psychology, keele university, uk corresponding author: yuh-shan ho, trend research centre, asia university, no. , lioufeng road, wufeng, taichung county , taiwan e-mail: ysho@asia.edu.tw abstract a ‘sleeping beauty’ is a term used to describe a research article that has remained relatively uncited for several years and then suddenly blossoms forward. new technology now allows us to detect such articles more easily than before, and such sleeping beauties can be found in numerous disciplines. in this article we describe three sleeping beauties that we have found in psychology – stroop ( ), maslow ( ) and simon ( ). keywords: citations, history of psychology, web of science, science citation index expanded as readers of this journal will know, a ‘sleeping beauty’ is a term that is used to describe a research article that remains relatively uncited for several years and then suddenly blossoms forward in this respect (van raan, ). an article that ‘awakens’ such a sleeping beauty is, relatedly, often called a ‘prince’. such ‘sleeping beauties’ can be distinguished from articles that are a ‘flash in the pan’ – i.e., articles that are highly cited at some particular point in their history and then promptly forgotten (li, ). sleeping beauties have been identified in several disciplines (table ) and also in specific journals. li and ye ( ), for example, present some examples of delayed discoveries in nature and kozak ( ) describes and discusses ones in current science. table about here modern computer-aided searching allows us to look for sleeping beauties more easily and more thoroughly than before. today several different researchers have developed different tools for doing this (e.g., du and wu, ; ke et al., ; li et al., ; wand et al., ). in this paper we describe the results that we obtained using a measure devised by yuh-shan ho (ho, ), one of the authors of this paper. more specifically we examined , documents in the psychology category of the science citation index expanded database of the web of science (updated on july, ). we used three main measures: : the total number of citations to a paper from initial publication to the end of . : the total number of citations to a paper in only. : the total number of citations in the period of sleep. using these data we found three sleeping beauties among , citations to articles in psychology – those of stroop ( ), maslow ( ), and simon ( ). table provides some summary data about these citations and their periods of rest. table about here figures , , and show the how each of these papers lay dormant for forty years or more before being awakened, by a ‘prince’ (braun et al., ; van raan, ; wang et al., ). figures , , and about here so why were such papers dormant and then ‘awakened’ from their sleep? in this case there appears to be three reasons – one for each paper. stroop provided a methodology that proved to be effective and easy to use in later studies in (different) areas of psychology. maslow’s notions about the nature of psychology - initially unpopular and idiosyncratic – came into fashion as psychology became more person-centred in the s. simon was prescient enough to see how computer-aided models of decision making grounded in economics would develop in psychology but it took time for people to realise this. however, what we have not shown in this article is why these particular papers were awakened after such delays, and by whom. subsequent analyses are needed to discover who made the citations that led to the re-discovery of these papers, and whether or not today sleeping beauties are simply footnoted as having made a major contribution to the field rather than discussed in detail. finally, it is perhaps worth observing that there may still be sleeping beauties out there undetected, or about to be awakened in different disciplines. we note with interest that shwartz and pfister ( ) have recently discovered the work of a certain ferdinand ueberwasse ( - ). this gentleman was apparently writing about psychology as a discipline approximately years before wilhelm wund. references braun, t., glänzel, w. and schubert, a. ( ), on sleeping beauties, princes and other tales of citation distributions ... . research evaluation, , - . du, j. and wu, y.s. ( ), a bibliometric framework for identifying “princes” who wake up the “sleeping beauty” in challenge-type scientific discoveries. journal of data and information science, , - . gorry, p. and ragouet, p. ( ), “sleeping beauty” and her restless sleep: charles dotter and the birth of interventional radiology. scientometrics, , - . healy, k. ( ), sleeping beauties in philosophy. https://kieranhealy.org/blog.archives/ / / /sleeping-beauties-in-philosophy/ ho, y.s. ( ), a bibliometric analysis of highly cited articles in materials science. current science, , - . huang, t.c., hsu, c. and ciou, z.j. ( ), systematic methodology for excavating sleeping beauty publications and their princes from medical and biological engineering studies. journal of medical and biological engineering, , - . ke, q., ferrara, e., radicchi, f. and flammini, a. ( ), defining and identifying sleeping beauties in science. proceedings of the national academy of sciences of the united states of america, , - . kozak, m. ( ), current science has is ‘sleeping beauties’. current science, , - . lange, l.l. ( ), sleeping beauties in psychology: comparisons of ‘hits’ and ‘missed signals’ in psychological journals. history of psychology, , - . levelt, w.j.m. ( ), sleeping beauties. chapter in i. toivonen et al (eds). structures in the mind: essays on language, music and cognition. mit press (in press). li. j. ( ), citation curves of “all-elements-sleeping-beauties: “flash in the pan” first and then delayed recognition. scientometrics, , - . https://kieranhealy.org/blog.archives/ / / /sleeping-beauties-in-philosophy/ li, j. and shi, d.b. ( ), sleeping beauties in genius work: when were they awakened? journal of the association for information science and technology, , - . li, j., shi, d.b., zhao, s.x. and ye, f.y. ( ), a study of the “heartbeat spectra” for “sleeping beauties”. journal of informetrics, , - . li, j. and ye, f.y. ( ), the phenomenon of all-elements-sleeping-beauties in scientific literature. scientometrics, , - . li, j. and ye, f.y. ( ), distinguishing sleeping beauties in science. scientometrics, , - . maslow, a.h. ( ), a theory of human motivation. psychological review, , - . mendel, g. ( ), versuche über plflanzenhybriden. verhandlungen des naturforschenden vereines in brünn, , - . ohba, n. and nakao, k. ( ), sleeping beauties in ophthalmology. scientometrics, , - . schwarz, k.a. and pfister, r. ( ), scientific psychology in the th century: a historical rediscovery. perspectives on psychological science, , - . simon, h.a. ( ), rational choice and the structure of the environment. psychological review, , - . stroop, j.r. ( ), studies of interference in serial verbal reactions. journal of experimental psychology, , - . van raan, a.f.j. ( ), sleeping beauties in science. scientometrics, , - . van raan, a.f.j. ( ), dormitory of physical and engineering sciences: sleeping beauties may be sleeping innovations. plos one, , article number: e . wang, j.c., ma, f.c., chen, m.j. and rao, y.q. ( ), why and how can “sleeping beauties” be awakened? electronic library, , - . wang, m.h., fu, h.z. and ho, y.s. ( ), comparison of universities’ scientific performance using bibliometric indicators. malaysian journal of library & information science, , - . glänzel, w., schlemmer, b. and thijs, b. ( ), better late than never? on the chance to become highly cited only beyond the standard bibliometric time horizon. scientometrics, ( ), - . garfield, e. ( ), premature discovery or delayed recognition: why? essays of an information scientist, , - . glänzel, w. and garfield, e. ( ), the myth of delayed recognition. scientist, ( ), - . mendel, g. ( ), versuche über plflanzenhybriden. verhandlungen des naturforschenden vereines in brünn, , - . table . articles on sleeping beauties in different disciplines disciplines references linguistics and psycholinguistics levelt ( ) medical and biological engineering huang et al. ( ) ophthalmology ohba and nakao ( ) philosophy healy ( ) physical and engineering sciences van raan ( ) psychology lange ( ) radiology gorry and ragouet ( ) science van raan ( ); ke et al. ( ); li and ye ( ) table . comparison data for three sleeping beauties in psychology author/date of publication total no. of citations no. of years sleeping no. of citations when sleeping stroop ( ) , maslow ( ) , simon ( ) , figure . the sleeping beauty life of stroop ( ) n u m b e r o f c it a ti o n s article life (year) figure . the sleeping beauty life of maslow ( ) n u m b e r o f c it a ti o n s article life (year) figure . the sleeping beauty life of simon ( ) n u m b e r o f c it a ti o n s article life (year) commentary: commentary: beauty requires thought | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /fpsyg. . corpus id: commentary: commentary: beauty requires thought @article{bluehm commentarycb, title={commentary: commentary: beauty requires thought}, author={katharina bluehm}, journal={frontiers in psychology}, year={ }, volume={ } } katharina bluehm published medicine, psychology frontiers in psychology view on pubmed frontiersin.org save to library create alert cite launch research feed share this paper topics from this paper published comment references showing - of references sort bymost influenced papers recency commentary: beauty requires thought s. luoto psychology, medicine front. psychol. highly influential view excerpts, references background save alert research feed aesthetics and the brain abstracts from the th critique of the power of judgment i. kant, p. guyer, eric matthews philosophy , highly influential pdf view excerpts, references background save alert research feed pleasure as self-maintaining motivation – a kant-based das „vermögen, durch […] lust […] zu urtheilen“ katharina bluehm art save alert research feed “ [ d ] as vermögen , durch [ . . . ] lust [ . . . ] zu urtheilen ” , in akten des . internationalen kant - kongresses ‘ natur und freiheit ’ in wien abstracts from the th visual science of art conference (vsac). art percept abstracts from the th visual science of art conference (vsac): berlin, germany, august th– th c. carbon, joerg fingerhut psychology save alert research feed aesthetics and the brain . abstracts from the th visual science of art conference ( vsac ) art percept . beauty requires thought a. brielmann, d. pelli biology, medicine current biology save alert research feed ... ... related papers abstract topics references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue pii: s - ( ) - neuron, vol. , – , may , , copyright  by cell press minireviewbeauty in the brain of the beholder groups that are unique to human culture has ensured that culturally specific characteristics are also transmit- ted with facial beauty. secondary sexual indicators on carl senior* laboratory of brain and cognition national institute of mental health male faces do not suggest that the bearer will placebethesda, maryland considerable investment in parental input. indeed, men with symmetrical faces are less likely to accept fidelity and will invest less time with offspring. when consider-facial beauty is an honest signal of the genotypic and ing paternity, men with facial characteristics that signalphenotypic quality of the bearer. beautiful people are a limited opportunity to attract multiple mates would bethus regarded as high-value mates who maximize re- considered to contribute more to reproductive successproductive success by producing viable offspring. than those advertising an ability to attract more thanhere, the functional neuroanatomy of facial beauty is one partner (penton-voak et al., ). interestingly,reviewed and placed into the context of the distributed men with neonatal facial characteristics, which advertisemodel for human face perception. a proposed exten- a limited opportunity to attract potential partners, tendsion of the distributed model is provided, which takes to have positive personality traits attributed to them byinto account the neuroanatomy of beautiful face per- female observers that may correlate with subsequentception. behavior. however, these personality traits are not indic- ative of actual behavior and may be fallible. to thisbackground end, female observers may consider male faces to beevolutionary theory suggests that facial beauty signals attractive if their same-sex peers consider them to bethe optimum reproductive status of the bearer; it thus attractive as well. thus, by copying the mate choice ofdictates that we are drawn to those who are attractive in same-sex peers, female observers act to increase theorder to maximize our success in reproducing offspring reliability of any assessments of facial attractivenesswith a strong chance of survival (references in symons, (references in thornhill and gangestad, ). ). take, for example, the effect of estrogen on fe- clearly, the ethology of beautiful face perception ismale faces; estrogen markers, such as fat deposits in complex, and considering the importance of selectingthe upper cheek and lip area, signal fertility and readi- high-value mates, the distinction needs to be made be-ness for reproductive effort (perrett et al., ). while tween beautiful faces that are rewarding in the sensethese markers are considered attractive by male observ- that they have an adaptive value (i.e., attractive different-ers, the estrogen to testosterone ratio fluctuates with sex faces) and those that are merely aesthetic (i.e., at-age such that female faces “masculinize” as the bearer tractive same-sex faces). an attractive female face maygets older. estrogen thus provides female faces with a be aesthetic but may also signal good genes that willmarker of youth—a marker that signals the optimal fertil- positively correlate with the genetic strength in any off-ity period for human females. additionally, in readying spring. however, to male observers, attractive malethe body for reproductive effort, estrogen diverts re- faces cannot constitute such a sociobiological adver- sources away from systemic functions such as cellular tisement and can only be considered aesthetic. consid- repair mechanisms and immunocompetency. facial es- ering the adaptive benefit behind perception of differ- trogen markers could thus be considered an honest ent-sex facial beauty and the subsequent motivated signal of the genotypic quality of the bearer, i.e., only behavior that occurs in observers assessing it, the brain those individuals strong enough to promote such a dis- areas implicated in reward function that underpin appe- play can afford to handicap vital functions. the same titive behavior are likely to be active with their percep- principle can be applied to male faces, where testoster- tion. however, considering the sole aesthetic value in one, which diverts resources away from immune func- attractive faces of members of the same sex, natural tion and toward the development of sexually dimorphic selection would have shaped any “beauty detectors” in facial traits, e.g., larger eyebrow ridges, contributes to the brain to become specialized for same- or different- the advertisement of genotypic quality (grossman, sex faces, but not both. while neuroimaging studies of ). such overt displays of systemic handicap allow facial beauty are scant, recent investigations do suggest observers to formulate judgments of the relative good sex-differentiated responses for perception of beautiful health of the bearer. a further facial marker considered faces, these studies are discussed later (aharon et al., attractive and indicative of the genetic superiority of ; o’doherty et al., ). however, our current un- individuals from either sex is “fluctuating asymmetry”— derstanding of the cognitive neuroanatomy of face per- the extent to which the left half of the face is the same ception does not account for these findings. to better as the right. the optimum development of facial symme- understand facial beauty and the brain, a brief discus- try is impeded by environmental stressors in utero, thus sion of the neuroanatomy of face perception is needed. the more symmetrical a face is the less that person has neuroanatomy of face perception been exposed to developmental stress (thornhill and the distributed human neural system for face perception moller, ). (distributed face model) is the most contemporary neu- however, the evolution of highly complex social roanatomical model encompassing what is known of face processing to date (haxby et al., ). this model is primarily based on functional neuroimaging data and*correspondence: carl@codon.nih.gov neuron figure . proposed extension of the distributed human neural system for face perception the solid lines represent parts of the existing model, while the broken lines represent the proposed extension. initial appraisal of facial beauty takes places in the slea and the ventral tegmentum (vt), where activity is reflected with a positive signal response in the orbitofrontal gyrus (gob), nucleus accumbens (nac), and ventromedial prefrontal cortex (vpfc) for rewarding beauty only. however, deactivity in the slea results in concomitant deactivitation in the nac during perception of aesthetic beauty. parses out the various processes involved in face per- rior insula. one area described in the distributed face model, the amygdala, has rich connections to manyception into two main systems. the first of these is the core system that is involved in visual analysis of the other areas implicated in reward and is thus pertinent to our discussion of the cognitive neuroanatomy of facialface. the second is the extended system, which projects out from the core system and computes the various beauty. classically, the amygdala is thought to process threat-types of information gleaned from the face. inside both the core and extended systems there is further func- related facial expressions (e.g., fear and anger); how- ever, it also plays a part in mediation of other expres-tional modularity. within the core system, the visual analysis of the variant aspects of the face (e.g., eye sions and social cognition in general (adolphs, ). recent studies of the amygdala suggest that it may alsogaze, expression, and lip movement) are computed in parallel to the invariant aspects of the face, such as the process meaning from the face that is unrelated to the facial expression being used as stimuli. this epiphenom-perception of identity. the functional subdivision of the extended system is based on the computation of spatial enal activity may be indicative of how the observer feels. take, for example, the now robust finding that directattention, prelexical speech perception, emotion, and unique biographical information. each of the subdivi- eye gaze engenders activity in the observer’s amygdala. while the ability to correctly infer the direction of gaze issions within the extended and core systems compute their respective functions in parallel; however, there is a fundamental human trait, it does, quite paradoxically, have ambiguous meaning. direct gaze can signal poten-reciprocal feedback between most of the units in the model (see figure ). tial threat but it can also indicate interpersonal attraction (haxby et al., ). the fact that presentation of facialunlike previous cognitive models of face processing, the distributed face model has neurological specificity, expressions of happiness (which are considered to be more attractive than other expressions) and looking atwith each unit in the model mapped to a distinct sub- strate. the core system consists of the inferior occipital people who you love evokes activity in the amygdala suggests that this area of the brain may play a crucialgyri, which mediate perception of early visual features of the face. the inferior occipital gyri project into the role in beautiful face perception (bartels and zeki, ). the extended amygdala and reward systemsuperior temporal sulcus (sts) and lateral fusiform gy- rus, which computes variant (expression) and invariant the amygdala is an umbrella term for a functionally and anatomically heterogeneous collection of nuclei that re-(identity) facial aspects, respectively. the lateral fusi- form then projects forward along the anterior temporal side in the superiomedial aspect of the anterior temporal lobes. the dense reciprocal interconnections that con-cortex, where personal semantic information regarding the face is represented, thus instigating familiarity. in vey information to and from a wide variety of neural areas ensure that the amygdala (or amygdaloid complex) isparallel to this, the superior temporal sulcus has recipro- cal projections to the intrapariatal sulcus, where spatial well situated to play an important role in the computa- tions that underpin the perception of beautiful faces. theattention from the face is processed. the ability to shift spatial attention from facial cues, such as interpretation various nuclei that constitute the amygdala are defined according to the particular functional criteria adopted,of gaze direction, is a fundamental skill allowing suc- cessful interaction in complex social groups. the supe- but it is generally agreed that there are two main clusters, these being the older and smaller corticomedial grouprior temporal sulcus also works in concert with regions within the superior temporal gyrus that are responsive to and the basolateral group (references in aggleton, ). the sublenticular (below the lentiform body) extendedmovements unique to speech. finally, there is reciprocal connectivity between the superior temporal sulcus and amygdala of the basal forebrain (slea) projects from the corticomedial group into the stria terminalis to formregions of the brain involved in emotion processing, such as the amygdala, orbitofrontal gyrus, and the ante- an extension of the “core amygdala.” the stria terminalis minireview project into the caudate body and to the nucleus accum- while male observers judged both beautiful male and female faces to be attractive, they only found the beauti-bens. due to the relay nature of the amygdala, the nu- cleus accumbens thus enjoys reciprocal connectivity ful female faces to be rewarding to look at and rated them as more attractive with multiple presentations.between the insular cortex, the hippocampal formation, the medial prefrontal cortex, as well as the orbitofrontal moreover, even though beautiful male and female faces were rated to be equally attractive, the male observersgyrus (heimer et al., ). further evidence showing projections from the corticomedial group to the dopa- only expended effort (via multiple key presses) to gaze longer at the beautiful female faces, showing that onlyminergic brain reward areas does suggest that it may play an initial role in perception of beautiful faces, with these faces were rewarding. to investigate the neural mechanisms involved in per-the brain reward system being “activated” at subse- quent stages (fudge and haber, ). ception of rewarding and aesthetic facial beauty, a third cohort of male observers were presented with picturesthe areas of the brain that mediate reward are diverse but are linked together through the medial forebrain of male and female faces (both average and attractive) in a block design imaging experiment. to ensure that thebundle—a complex structure consisting of approxi- mately fiber bundles that project through the lateral fmri results were not contaminated by the attentional modulation of gaze, all material was presented to thehypothalamus toward the rostral basal forebrain. the ventral tegmentum is a dopaminergic site that is con- subjects tachistoscopically ( ms), and each picture was separated with an interstimulus period of ms.nected by a descending component of the medial fore- brain bundle. the ventral tegmentum also projects to several regions of interest were first defined by com- paring engendered activity in all experimental condi-other areas of the brain, such as the nucleus accumbens and the orbitofrontal gyrus, which are now seen to play tions with any activity revealed within the control period (which only consisted of a fixation cross). this analysisa role in the brain reward process (rolls, ). these systems would have evolved to ensure the appetitive served to localize the regions of interest that were sub- sequently studied for the specific experimental effects.drive toward stimuli that were beneficial to our survival as a species. in light of the adaptive benefits behind presenting male subjects with beautiful female faces (which would involve both reward and aesthetics) en-beautiful faces, one would hypothesize involvement of these substrates. recently, functional magnetic reso- gendered significant activity in both the right orbitofron- tal gyrus and bilateral nucleus accumbens. this analysisnance imaging (fmri) was applied in an effort to under- stand more about the processes mediating perception also revealed activity, albeit at a lower threshold, in the ventral tegmentum and slea. the brain areas revealedof beauty (aharon et al., ; o’doherty et al., ). the results of these investigations place facial beauty with the analysis of the rewarding beautiful faces repre- sent a subcortical distributed system, with each compo-alongside emotion and speech as a fundamental condi- tion that can be read from the face and also suggest that nent contributing a specific role to perception of facial beauty.aesthetic and rewarding properties of beautiful faces are processed separately. lesions to the sublenticular nucleus reduce the re- warding effect of stimulation in the medial forebrain bun-neuroimaging studies of facial beauty in the aharon et al. ( ) study, a behavioral task was dle (arvanitogiannis et al., ). the slea and the ven- tral tegmentum share a common pathway through thefirst given to a group of heterosexual male observers who where asked to rate the attractiveness of average medial forebrain bundle, and activity has been revealed in the dopaminergic neurons of the ventral tegmentumand beautiful male and female faces. this task revealed a clear difference between the beautiful and average to salient sensory events which have no relationship to reward (horvitz, ). it may be the case that the sleasets, regardless of the sex of the face. however, this difference was modulated by the amount of time that and the ventral tegmentum operate together to form an “appraisal unit” that is the first, and common stage, inthe observer saw faces belonging to a particular group. the beautiful female faces were rated as more attractive perception of beautiful faces. on the other hand, the orbitofrontal gyrus is specifically active when the subjectwith each presentation, while the average female faces were rated as less attractive. on the other hand, the is anticipating a reward outcome that could contain ei- ther a positive or negative valence (schultz and dicken-beautiful and average male faces did not reveal such a separation of ratings with subsequent presentations. a son, ). the dopaminergic meso-accumbens path- way plays a central role in the initiation of motivatedsecond cohort of male observers underwent another behavioral task where they could manipulate the length behavior, with the nucleus accumbens involved in the assessment of reward expectancy (breiter and rosen,of time that a picture of a face remained on the screen. the duration of presentation could be extended or short- ). thus, these areas of the heterosexual male brain encompass the appraisal, anticipation, and assessmentened when the subject pressed a specific key on a key- board. it was hypothesized that male observers would of the reward value inherent in beautiful female faces. aharon et al. ( ) then investigated the effects ofmake multiple keypresses to gaze longer at those faces that were rewarding (i.e., the attractive female faces). the aesthetics of facial beauty only (i.e., beautiful male faces versus average male faces). as before, the ventralperhaps unsurprisingly, the results confirmed this hy- pothesis, with male observers choosing to gaze longer tegmentum was active; however, the slea revealed a negative signal response (deactivation), suggesting thatat the beautiful female faces. there was no difference between the length of time the observers chose to look these areas may respond together in an additive manner for aesthetics in rewarding faces only. in addition toat the average female and male faces and the attractive male faces. these results converge on a behavioral dis- this, a bilateral deactivation was revealed in the nucleus accumbens. the pattern of activity revealed in the nu-sociation of the qualities that constitute facial beauty. neuron cleus accumbens for aesthetic beauty is supported by proposed module for the rewarding beautiful faces also studies of reward expectancy. for example, a decrease represents activity in the orbitofrontal gyrus and ventro- in the fmri signal from baseline is revealed when an medial prefrontal cortex, as activity here was specific expected reward is not delivered (knutson et al., ). to this set of faces only (see figure ). it would seem likely that the bilateral deactivation in the one caveat has to be stressed: as noted above, few nucleus accumbens for the aharon et al. ( ) study neuroimaging studies on facial beauty exist, and as signaled an absence of reward expectancy toward the such, the proposed extensions of the distributed face beautiful male faces. model will have to remain provisional until the necessary in a later fmri (event related) experiment, the cortical empirical investigations confirming their robust validity response to male and female beautiful faces for observ- are carried out. ers of both sexes was studied (o’doherty et al., ). selected readingin this study, no activity in the nucleus accumbens was revealed when male and female subjects were shown adolphs, r. ( ). curr. opin. neurobiol. , – . attractive and average faces of both sexes. however, aggleton, j.p. ( ). the amygdala: a functional analysis (oxford:as aharon et al. ( ) showed a positive and negative oxford university press). signal change for attractive female or male faces, the aharon, i., etcoff, n., ariely, d., chabris, c.f., o’conner, e., and presence of activity in the nucleus accumbens cannot breiter, h.c. ( ). neuron , – . be considered an artifact brought about with the use of arvanitogiannis, a., waraczynski, m., and shizgal, p. ( ). physiol. a block experimental design. it remains to be tested behav. , – . whether or not deactivation in the nucleus accumbens bartels, a., and zeki, s. ( ). neuroreport , – . when observers are shown attractive same-sex faces is breiter, h.c., and rosen, b.r. ( ). ann. n y acad. sci. , unique to the heterosexual male population. interest- – . ingly, this study also revealed activity within the ventro- fudge, j.l., and haber, s.n. ( ). neuroscience , – . medial prefrontal cortex for heterosexual male observ- grossman, c.j. ( ). science , – . ers viewing attractive female faces. given the role that haxby, j.v., hoffman, e.a., and gobbini, i. ( ). trends cogn. sci. the ventromedial prefrontal cortex may play in social , – . reasoning, it seems likely that it works in concert with haxby, j.v., hoffman, e.a., and gobbini, i. ( ). biol. psychiatry the orbitofrontal gyrus to compute reward expectancy in , – . a possible social context (references in adolphs, ). heimer, l., alheid, g.f., de olmos, j., groenewegen, h.j., haber, even so, the pattern of activity revealed for the analysis s.n., harlan, r.e., and zahm, d.s. ( ). j. neuropsychiatry clin. of aesthetic and rewarding beautiful faces is not ac- neurosci. , – . counted for in the distributed face model; modifications horvitz, j.c. ( ). neuroscience , – . of the extended system of this model are proposed to knutson, b., adams, c.m., fong, g.w., and hommer, d. ( ). j. account for these findings. neurosci. , . beauty in the brain o’doherty, j., winston, j., critchley, h., perrett, d., burt, d.m., and dolan, r.j. ( ). neuropsychologia , – .the data to hand suggest that the slea and the ventral tegmentum serve a pivotal role in the initial appraisal penton-voak, i.s., perrett, d.i., castles, d.l., kobayshi, t., burt, d.m., murray, l.k., and minamisawa, r. ( ). nature , – .of beautiful faces. as described above, the amygdala perrett, d.i., lee, k.j., penton-voak, i., rowland, d., yoshikawa, s.,receives input from the superior temporal sulcus. how- burt, d.m., henzi, s.p., castles, d.l., and akamatsu, s. ( ). na-ever, as the computations carried out by the slea and ture , – .ventral tegmentum, and the subsequent projections to rolls, e.t. ( ). cereb. cortex , – .the nucleus accumbens, are distinct from emotion pro- schultz, w., and dickenson, a. ( ). annu. rev. neurosci. ,cessing per se, they are represented alongside the – .“emotion module” in the distributed face model and not symons, d. ( ). the evolution of human sexuality (oxford: ox-projected out from within. the projection from the sts ford university press).to the slea and ventral tegmentum is supported by thornhill, r., and gangestad, s.w. ( ). trends cogn. sci. ,work showing modulation of the brain reward system by – .eye gaze, a manipulation previously found to engender thornhill, r., and moller, a.p. ( ). biol. rev. camb. philos. soc.activity in the anterior bank of the sts (haxby et al., , – . ). when subjects are presented with beautiful faces that are rewarding, engendered activity in the sublenticular nucleus is mirrored with activity in the ventral tegmen- tum, orbitofrontal gyrus, and nucleus accumbens. how- ever, beautiful faces that are merely aesthestic engender a negative signal change (deactivation) in the slea and the nucleus accumbens. due to the opposite directions of signal response in the nucleus accumbens for percep- tion of aesthetic and rewarding beautiful faces, these computations are represented separately. therefore, projections from the module representing the slea/ven- tral tegmentum diverge into two separate pathways— the first represents the processing of rewarding beautiful faces, and the second represents the aesthetic. the wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ ba .pdf books may / vol. no. www.biosciencemag.org versus bacteria as useful facilitators of various industries and technolo- gies. the book’s subtitle, however, may require more of a departure from a human-centered point of view. although maczulak hints at it through- out, i don’t think she quite captures with examples the overwhelming and pervasive existence of microbes that is completely separate from (and oblivious to) the narrow interests of humans. maczulak may interpret the “world” to mean the human world, but the fact is that we humans dwell within a bacterial world, which maczulak fails to firmly establish. it is a challenge with any popular book on bacteria to know the back- ground and expectations of its tar- get audience. maczulak attempts to include general information on cells throughout the book, but with a vol- ume of just pages, it may have been more efficient to start with basic microbiology, make several main points understood in the first chapter, and then move on to the illustrative examples. instead, her efforts at intro- duction were confusing. for exam- ple, archaea are briefly introduced as being synonymous with extremophiles, which they are not; there may be many more mesophilic archaea. meanwhile, maczulak confounds her assertion by introducing various interesting extre- mophiles, among them both bacteria and archaea, but she fails to distin- guish between the two. ten pages later comes the canonical woesian family tree that typically introduces archaea. opposites: strong diversifying selection versus relaxed constraint. this type of alternative explanation, founded in classical theory, is not often discussed and is overlooked in the enthusiasm to embrace newer, but untested, con- cepts. one field likely to be enhanced by this volume is evolutionary develop- mental (evo-devo) biology. antici- pation of the merging of these two disciplines has been ongoing for years; in fact, wright, who joined the faculty of the univer- sity of chicago in , was hired by the great embryologist and then chair of the department of zoology frank r. lillie, with the expectation that wright’s research would help integrate the fields of evolution and development. almost every chapter in this work is relevant to evo-devo students. although some current top- ics also construed as extensions of the modern evolutionary synthesis (e.g., new discoveries in human evolution, biochemical taphonomy, geoimaging technologies) do not appear in this book, i strongly recommend the read- ing and critical discussion of evolu- tion—the extended synthesis to all. michael j. wade michael j. wade (mjwade@indiana .edu) is a distinguished professor of biology at indiana university in bloomington. where is the beauty and excitement of the bacterial world? allies and enemies: how the world depends on bacteria. anne maczulak. ft press, . pp., illus. $ . (isbn cloth). as the primary title of anne mac-zulak’s book promises, most of the content of allies and enemies: how the world depends on bacteria concerns the dichotomy of bacterial pathogens argument and serious constraints on its usefulness. the book discusses amazing exam- ples in the literature of plastic and adaptive phenotypes, including the famous defensive morphologies of daphnia induced by the presence of predators; the winged and wingless morphs of bean beetles induced by resource depletion; and the quorum- sensing genes of bacteria, which con- trol suites of genes, induced by high density. the latter are particularly important to human health because of their role in virulence and the forma- tion of biofilms. in contrast, when a gene is expressed only in response to a specific environ- mental stressor, spatially or temporally restricted in its extent—such as extreme temperatures, density, or disease—that gene does not experience very strong natural selection. copies of the gene are not expressed in those individuals who do not encounter the environment. as a result, these genes are not screened by natural selection but rather become targets for mutation. total selection on the genes underlying the capacity for plastic phenotypic responses is the average of the selection experienced by the proportion of copies expressed and the proportion not expressed. total selection is weakened because of this averaging, and the mutational load of these genes is increased in propor- tion to the rarity of the environment. indeed, adaptation to very rare envi- ronments is hardly possible: if not expressed frequently enough, muta- tion, accumulation, and mutational meltdown eliminate the genetic basis for the capacity for such flexibility. if all is not lost, then the expected level of polymorphism for persisting genes will be higher, as will the divergence of these genes among closely related taxa. although evolutionary biologists prefer to interpret genetic differences among taxa as being the result of strong positive natural selection, these “plasticity genes” diversify among taxa for the opposite reason—a relaxation of selection. the pattern across taxa is the same—immense diversifica- tion—but the explanations are polar doi: . /bio. . . . www.biosciencemag.org may / vol. no. books since maczulak’s focus throughout the book is the detailed recounting of the history of microbiology, i wish she had also tackled the history of carl woese’s reinvention of the field. this approach might have introduced and showcased archaea more effectively. in other places, while trying to provide some basic biological infor- mation, maczulak makes generaliza- tions that are too casual, as when she declares that bacteria are less bound by the sort of spatial constraints that limit protozoa to aquatic places and fungi to soil. in a book this succinct, the back- ground material must be chosen care- fully and used with more precision. all bacteria and archaea are aquatic in that their reproduction and metabolisms require water in the environment, even if only a thin film around a particle. maczulak also declares that the over- whelming majority of bacteria live in soil. if she is including all sediments in oceans and other bodies of water as “soil,” as well as all of the tropical substrates that are not quite soil, then this statement might be true, but it is too loose a comment to be stated on its own as fact. the history of microbiology can be presented as inspiring reading— paul de kruif being the leader of that genre. the strengths of allies and enemies all lie in the sections in which maczulak delves into detail about the personalities and lives of her protagonists: the events in koch’s and hesse’s lab are nicely depicted, the interactions of pasteur and winogradsky are well developed, and the history of escherichia coli is thoroughly researched and interest- ingly written. maczulak’s ability to tell a good story is highlighted again in her descriptions of the myriad bacteria in and on the human body. as an aside, i disagree with maczulak that hooke is a forgotten hero of bac- teriology; he merits numerous pages from historians and philosophers of science for his many accomplish- ments. hooke’s particular micro- scope design, however, was never as effective as van leeuwenhoek’s. hooke’s subjects were much larger segues into a discussion of bacteria as destroyers of the artwork itself. alas, i had been hoping that maczulak would review the growing body of art that celebrates bacterial ubiquity and diversity. often, such art is colorful and transient, involving flows of living bacteria interacting on a substrate. a surprising epilogue appears at the end of the book, containing informa- tion typically found in introductions to microbiology lab manuals. maczu- lak includes instruction on how to do serial dilutions, how to count colonies, and even how to use logarithms to calculate large numbers. as one who has written a book on bacteria, i know it is a challenge to frame the audience. i think both maczulak and i would like to envision our readers as so enthu- siastic about microbes that dabbling in the laboratory would be their next irresistible step. but in the case of allies and enemies, those extra pages of instruction may have been better used to reinforce the grand scale of everything bacterial. betsey dexter dyer betsey dexter dyer (bdyer@ wheatoncollege.edu) is a professor of biology at wheaton college in norton, massachusetts. serious evolutionary genetics elements of evolutionary genetics. brian charlesworth and deborah charlesworth. roberts and company, . pp., illus. $ . (isbn cloth). wherever the study of evolu-tion intersects with the study of inheritance we have evolutionary genetics. evolutionary genetics thus covers a huge chunk of evolutionary biology, as without inheritance there can be no cumulative change. the objects, such as fleas and fly eyes, and never cells of bacterial size. the tone of the book changes when maczulak tries to clarify what we know and do not know about the origins of antibiotic-resistant bacteria. although the origins of some antibiotic-resistant bacteria can be isolated to stockyard animals dosed with prophylactic antibiotics, she claims that “it can be difficult to prove” any real connection. i was at first puzzled by the prevarications in this section and then wondered whether maczulak was speaking from some firsthand experience with the beef industry. (she has a consulting firm that deals with compliance audits for industries concerning microbes.) if so, i wish that she had told the story more directly in the book instead of presenting it as an intractable prob- lem. a similar equivocal tone appears in the section on genetically modi- fied food, another topic that might have benefited from a more forthright approach that included the author’s experiences with such industries. segments of the book that are not about pathogens tend to be about bacteria as essential providers for specialized activities in industry and technology. this dichotomy of bacte- ria acting as either pathogens or indus- trial aids is already pervasive in the popular press and does not need such reinforcement. another disconcerting theme i found in allies and enemies is the idea of “our” world being primar- ily inhabited by bacteria. put more accurately, it is their world that we inhabit. bacteria simply dominate the ecosystems; have been and continue to be intrinsically influential in our evo- lutionary history; and, quite simply, make nutrient cycles of life possible. the final chapter concludes that bacteria are our best friends and that we should stop worrying about germs. yet more than half of the book is focused on the pathogenicities of bac- teria and their relentless resistance to the best antibiotics. the chapter “bacteria in popular culture” empha- sizes depictions of plague and tuber- culosis in art and literature and then doi: . /bio. . . . testfile beauty. a brief conceptual journey author martin seel affiliation goethe universität, frankfurt am main abstract: the journey i have arranged is strictly conceptual; it deals with the systematic implications of the concept of beauty. it begins in rocky lowlands and ends in astounding heights. but i promise, the journey will be brief. i develop my guiding concept in an increasingly adventurous manner—as adventurous at least as one can be in the realm of the conceptual. my suggestion simply is: sit back and enjoy the ride. a conceptual journey will presumably not seem all that attractive to potential readers. some of them might think i intend to narrate the history of the concept of beauty, that i will present diverse understandings of beauty as they have developed through the centuries. but if that was my intention, i could have just said it straight out. no, the journey i have arranged is a strictly conceptual one; it deals with the systematic implications of the concept of beauty. it begins, as is customary of philosophical endeavours, in rocky lowlands and ends in astounding heights. but i promise, the journey will be brief. so i will be developing my guiding concept in an increasingly adventurous manner—as adventurous at least as one can be in the realm of the conceptual. at the end, some participants in the journey will probably no longer wish to follow me, even though they will see how dizzying a conceptual journey can turn out to be. so my suggestion simply is: sit back and enjoy the ride. c© aesthetic investigations vol , no ( ), - beauty. i. the journey . as is well known, beauty is a species of the good, for everything that is immediately experienced as good can be praised by using aesthetic predicates such as ‘beautiful’, ‘wonderful’, ‘nice’, ‘elegant’, ‘charming’ etc. all these terms and their many relatives evaluate something as good—not in the sense of being good for something else, but in and of itself. in the german language at least, it is completely natural to talk about a ‘beautiful proof’, a ‘beautiful event’ or of ‘a beautiful thing of you to do’ (letting me continue to sleep), whereas english speakers on such occasions will apply terms such as ‘elegant’, ‘wonderful’ or ‘nice’. however different the linguistic practices of aesthetic praise might be, all of the things to which we ascribe such predicates fulfil one basic condition of beauty—to be in such a way that the thing or event itself is valuable. this is likely the most everyday meaning of the term beauty and its rel- atives: it refers to something with intrinsic value, that is, something that is not, or not only, good in an instrumental sense and thus worthwhile being attended to. . to be beautiful in a stronger sense, a second condition must also be fulfilled: a thing must appear in such a way that it shows itself to be intrinsically valuable. only here does beauty take on its actual aesthetic significance. (as we saw in my first condition, the word beautiful and its relatives do not always have a straightforward aesthetic meaning.) that which has its purpose in itself and is thus beautiful in this pre-aesthetic sense does not necessarily appear in its goodness. but if it takes on this appearance, it is certainly more beautiful (and the word ‘beautiful’ takes on a clearly aesthetic meaning.) what is intrinsically good reveals itself to our senses: a cogent proof is elegant, an event takes place on a sunny day, a look of care or love lights up your eyes. in these cases, the good can be separated from its appearance as something good, but only this improbable appearing brings to light what it actually is—something that is good for its own sake and entirely worthy of being perceived. here as well, we are very close to the aesthetic of everyday experience: of objects and situations, which exist for their own sake and whose presence can occupy, or temporarily captivate a given observer, be they parks or people, restaurants and their menus, auditoriums or automobiles. in these instances of potential beauty, by the way, instrumental qualities often play a significant role: a beautiful chair is at least halfway comfortable, a beautiful car handles rather well, a beautiful lamp radiates a decent light, a beautiful building is also functional. but as long as we speak of beauty, this instrumental or functional goodness can never be the core of our aesthetic dealings with or experience of these things or events (and thus also not the core of our martin seel judgments about them). instead, that core lies in the opening of an encounter with a relieving, exhilarating or even enchanting present. . in a different and often more intense manner, something can be experienced as beautiful if it is an instance of the good which enters the world solely on the power of its appearing. it thereby fulfils a further condition of beauty: to be good in and of itself, indivisible from the sensations of its appearing. in moving landscapes and passionate works of art, space and time acquire a shape in which every sort of fulfilment remains bound in its sphere. how- ever much meaning and significance, value and truth might be contained in these situations, everything about them feeds on the intensity of a play of inexhaustible forms. taking part in this play of gestalten, wherever and whenever it might take place, necessarily entails breaking with the continuities of everyday life and, not seldom, opening up an exit from these continuities. the decisive fea- ture of this type of beauty is a constitutive interdependence of sensible form and—depending on the circumstances—existential, historical, cultural, polit- ical or philosophical content in the face of its respective manifestations. the way in which something is or touches us always depends on how it presents itself; every physical and psychic instance of ‘being moved’ on the part of the perceiver is determined by its phenomenal movedness. here, nothing can be good unless it does good: the quality of beauty is no longer an accessory or an add-on to qualities that would be valuable in other regards; it lies solely in the sensations of its contingent or artificial configuration. . the presence of beauty receives a final modification when within it a fourth condition is fulfilled; that is, when something becomes an event revealing no other good besides the swirl of its appearing—when for instance a desired body, a beguiling city, a thunderous storm or a captivating building is so present that we simply cannot let go of its existence and our being here. here, the gap between the aesthetically perceived object and the aesthetically perceiving subject fuse to create an ecstatic affirmation of the situation of this perception itself, whose intensity is virtually sparked by a momentary configuration of things and events, of their emergence and disappearance. the sound of nature and music in particular invites us to do so, time and again. to be receptive to this beauty means being sensitive to—and thus threatened by—the event of an uprising of the present in the midst of the rest of time. . well, that’s it. our journey has taken us to four stations. i. in its simplest form, beauty is a matter of being good in a way that is not, or not merely, beauty. instrumental. ii. in its elementary aesthetic form, beauty is a matter of circumstances and occasions, of all kinds, appearing as good. iii. in an additional meaning, the experience of beauty leads to a dwelling in the face of objects, for its own sake, whose inner quality cannot be divided from the play of its appearances. iv. in an ecstatic form, beauty occurs as the unbound perception of a present that can be affirmed in a unique fusion of presence and absence. or, to put it in one sentence, all instances of beauty are something good in itself, but particularly the appearing of something that is good in itself, especially within the landscapes of nature and art. . at the very least, these four steps help us understand why it has repeatedly been claimed that ethics and aesthetics are one, or at least extremely closely related. after all, some of what is good in itself is also beautiful in an aesthetic sense, and everything that is beautiful is good in itself. you may have noticed, therefore, that my brief story of beauty contains a strong historical ingredient. strictly speaking i have recalled, in a rather heterodox manner, the platonic conception—influential for the entire tradition of aesthetics, all the way up to gadamer and adorno—that beauty is an appearing of the good and—but this is my qualification—sometimes of what is true in a cognitive sense as well. to be sure, this philosophical link of beauty and the good and the true has often been mocked (just think of nietzsche); however, i believe it touches the heart of the matter. it does so especially if we take the true in the attributive sense in which it converges with the good anyway (for instance, when we speak of ‘true friends’ or ‘true pleasures’ or when an advertisement proffers ‘the one true beer’). yet the link between this sense of the true—the truly good—and propositional knowledge is in no way coincidental; after all,—to exaggerate just a bit—the entire meaning of conceptual knowledge is to guide us in our orientation towards what is ethically true, be it the existential or the moral and political good. in the present context, however, another consequence is more important. it is the concept of beauty—and not one of the more recently introduced rival concepts—that not only has traditionally dominated the field of aesthetics, but that should dominate it in our day as well. it should be noted, however, that the predicate ‘beautiful’, just like the predicate ‘good’, has a nearly endless amount of counterparts—just think of aesthetic (or aesthetically used) words such as ‘pretty’, ‘attractive’, ‘elegant’, ‘suspenseful’, ‘overwhelming’, ‘awesome’, ‘subtle’, ‘staggering’, etc. or think of the many synonyms of ‘good’, of adjectives such as ‘just’, ‘honest’, ‘serious’, ‘courageous’, ‘clever’, ‘generous’, or ‘friendly’. these innumerable terms give our esteem for—or our disapproval of—ethical and/or aesthetic phenomena a more appropriate, because more precise, expression than do brute concepts such as ‘the good’ and ‘beauty’. nevertheless, what is true of the concept of the good is also true of the concept of beauty: it, and only it, forms the fundamental and, in this martin seel regard, unrivalled category of philosophical aesthetics, thus also providing, of course, a basic category of philosophy in general. the explication of such categories, of beauty in our case, is capable of illuminating and providing the rationale for the basic interest humans have in the diverse forms of aesthetics. so it is no wonder that the signs of a rehabilitation of beauty have been gathering for some time. ii. additional observations even after conceptual journeys, there are always quite a few stories to be told. that’s why i will now present a short series of additional narratives (or post-remarks), the main point of which is to make clear that my previous considerations were not quite as reactionary as they may have seemed. this is because my short cuts contained a heterodox message about both the classic and the classic modern understanding of beauty. . nevertheless, there is a fundamental opposition between beauty and the good, for the former entails a rejection of what is merely instrumentally good. it stands in opposition to everything that is only good for the sake of something else, instead of being good for the sake of its own or of our own existence. the diversity of beauty is an unending advertisement for the diversity of these species of the good. the four-fold meaning of beauty therefore contains a simple message: time and again, we should give up the search for higher and further-reaching meaning and purpose. (a sense of beauty is in this way an anti-fundamentalist sense.) . a sense of beauty entails a sense of the horrible. not because the horrible is beautiful, which taken in itself is not the case. (it only seems that way to those who are blinded anyway.) instead, by dwelling in the face of the horrible, we dwell in our sight of it—with a power of perception to increase its own capacity through everything, even the most horrible. this is a capacity to find what is thrilling in what seems inconspicuous and what is inconsolable in what seems glorious. in the name of beauty, a sense for beauty is not fixated upon beauty. it can preserve its passion for the exceptional even when the shock of an appearing object promises nothing but the pure exercise of the most extreme awareness. in this borderline case, any enjoyment of the presence of a beautiful object disappears, but not the enjoyment of the fragility of the perceiving subject. adorno raised this borderline case to the paradigmatic case of an aesthetics in dark times, when he wrote in his minima moralia that ‘there is no longer any beauty or consolation, except in the gaze that goes straight to the terror, withstands it and in the undiminished consciousness of negativity, holds fast to the possibility of that which is better.’ even though it is highly questionable to declare this extreme of beauty to be the core of beauty. beauty, since the exception it represents would no longer be comprehensible (an exaggerating procedure, however, that illuminates the method of this entire book) it remains true that the sense of beauty stops for nothing and no one. it is gruesome in the sense that it doesn’t recoil at the perception of gruesomeness. that is how the sense of beauty shrinks back from it—by refusing to glorify it. that is how it stands up to the horrible—by standing behind a perception of the horrible that does not take the step of affirming it. the sense of beauty can be beguiled and unsettled by many things, but it doesn’t let itself be convinced that it needs the horrible in order to be horrified aesthetically, nor that the enjoyment of the representation of the horrible in the danger zone of art is an enjoyment of the existence of the horrible. . the opposition between beauty and the sublime is artificial. the world in visible proportion or in visible disproportion to one’s own possibilities—that is not what is captivating. rather listening for what is not harmonious in that which is, and for what is harmonious in that which is not is. depending on the tonal mixture, we can name the occasion for such an awareness ‘beautiful’ or ‘sublime’ or use some other aesthetic adjective. but each lacks suspense without the other. beauty that smoothes us without vexing us is not beauty; something that is sublime and unsettles us without liberating us cannot lift us up. the land of the aesthetic knows no borders. that is what the aesthetic is: refusing to delimit our ability to perceive. my claim, however, is not that there are no differences in the land of the aesthetic, for there are obviously more than enough of these. but i believe that we misunderstand a difference, such as the one between beauty and the sublime, if we do not see these values as a polarity within beauty, and thus as an often latent tension between the four particular species of the good i distinguished at the beginning of this essay. . whoever doesn’t regard the paintings of francis bacon as beautiful will not be able to find what is unsettling about them. or think of cinema. in certain circles, horror films such as texas chainsaw massacre enjoy cult status, even though these films are not beautiful in the normal sense in their—likewise intentional—primitiveness and atrociousness, and thus are not good films according to customary standards. nevertheless, the fans of such things take special pleasure in viewing them, precisely because, as instances of a very particular artistic genre, they lack any good taste whatsoever. for them—the fans—these films are highly sophisticated products, whose play with horror gives them a special aesthetic appeal and makes them appear successful, which is why from this perspective it is not paradoxical to talk of a ‘nice horror movie.’ in my opinion (and now of course i will continue to make aesthetic judgments in order to clarify certain consequences of my theoretical martin seel understanding of beauty), things are entirely different when it comes to films such as the grindhouse double feature death proof ( ) and planet terror ( ) directed by quentin tarantino and robert rodriguez, which in their extreme violence unfold a surreal and ironic play on various film genres. i could name several other films in this context, such as scarface, directed by brian de palma ( ), in which a chainsaw also makes an unpleasant appearance, or the alien trilogy, especially the first part directed by ridley scott ( ). these are films that present gruesomeness, terror and fear in a ghostly light, and lead us into fascinating zones of the ambivalence of human self-experience, because they create an outstanding form for such a purpose—and thus a form of beauty. . since these last remarks will not strike everyone as being immediately plau- sible, in closing, i want to cite two artists who can definitely not be viewed as practicing a rosy, soothing, trivializing, or kitschy aesthetic. the first is michael haneke, who with regard to his films—such as funny games, code unknown, the piano teacher or caché—is repeatedly accused of favouring an exaggerated and even inhumane attitude of coldness (an accu- sation, by the way, that i take to be unjustified). in an interview with thomas assheuer in , he commented on the relationship between precision and beauty: ‘i can be enthusiastic about the beauty of a thing. but i can also be enthusiastic about the precision of a thing. the primary virtue of art is precision. be it painting, literature or film—it is all about observing as precisely as possible, and about rendering that observation as precisely as possible. (. . . ) one could even say that intensity arises through precision in matters of detail. that is why precision is both an aesthetic and a moral category. it represents an obligation, the moral imperative of art, so to speak.’ at which point the interviewer asks: ‘and from precision arises in turn— beauty?’ haneke’s answer: ‘yes, beauty has nothing to do with prettying something up. even the fragment is a form and not the opposite of form. one must always find the appropriate form. (. . . ) the measure of artistic value is precision and therein lies pure desire. (. . . ) for that reason alone it is worth working, and that gives rise to enthusiasm. i don’t have to want to please anyone by doing so. i believe that precision per se is pleasing.’ . my second witness is imre kertész, the hungarian nobel-prize winner, who in his youth survived internment in several concentration camps. this is also the basis of his novel fateless and is, directly or indirectly, a point of reference for all of his later works. his work file k was the product beauty. of a detailed interview with an editor and friend, which kertész transformed into an autobiographical dialog that swings back and forth between ego and alter ego, shifting with virtuosity between self-doubt, introspection and self- assertion. at one point, the conversation turns to adorno’s dictum that it is barbaric to write poetry after auschwitz. ‘i cannot comprehend,’ says kertész, ‘that a mind like adorno can assume that art should refrain from dealing with the greatest trauma of the twentieth century. should we view the poems of celan or miklós radnóti as barbaric? that is a bad joke, nothing else. and as far as ‘aesthetic enjoyment’ goes: does adorno expect these great poets to write bad poems? the more one analyses this unfortunate sentence, the more nonsensical it becomes.’ before this passage, the fictitious interviewer asks the author, kertész, about his narrative the union jack and remarks that the story seems to ‘glorify’ what it represents. ‘glorify?’ answers kertész. ‘i don’t understand what you mean.’ his counterpart cites a passage. kertész repeats his ques- tion: ‘what is your problem with the text?’ the interviewer responds: ‘my problem is that i like to read it, that i even enjoy it. even though the point of the union jack is the aporia of grasping reality through writing.’ the author responds: ‘that’s not the only point of the text. but i’m beginning to understand your point. whether we like it or not, art always views life as a celebration.’ — ‘as a carnival or as a funeral?’ — ‘as a celebration.’ . note that the voice of kertész does not claim that life is a celebration, but that art conveys life as a celebration, however horrible or perverse might be that with which art confronts us. and it is precisely this extreme passage, taken together with haneke’s apology for aesthetic precision and cruelty, which in my opinion teaches us something about the specific success of art. works of art convey what they present by means of a form that compels the reader, viewer or listener into what is at the same time a captivating and liberating awareness—into a celebration of receptiveness and spontaneity paired with a capacity for fantasy and insight, unlike anything of which other modes of thinking are capable. seel@em.uni-frankfurt.de translated by joseph ganahl notes . a beautiful chair, by contrast, that is painful to sit in satisfies our aesthetic need just as little as an ugly chair that is utterly cozy. a chair, after all, is not just a sculp- ture; but as soon as it becomes an object of aesthetic desires, neither is it only a useful seel@em.uni-frankfurt.de martin seel object. . seel , - . . seel , - . . e.g. e. scarry, on beauty and being just, princeton , a. nehamas, only a promise of happiness: the place of beauty in a world of art, princeton ; b. recki, ‘herabkommen ins sichtbare. ei- ne apologie der schönheit in pragmati- scher hinsicht’, in: r. konersmann (hg.), das leben denken—die kultur denken, bd. : leben, münchen , - ; r. scruton, beauty: a very short intro- duction, oxford ; k. p. liessmann, schönheit, wien ; k. h. bohrer, ‘was kann kritik sein am ende der kunst- kritik?’, in: merkur / , - ; g. figal, ‘Über die schönheit der moder- nen kunst’, in: internationales jahrbuch für hermeneutik / , - ; c.-s. mahnkopf, ‘die schönheit (in) der musik’, in: musik & ästhetik, / , h. , - ; c. menke, ‘die schönheit: zwischen an- schauung und rausch’, in: die kraft der kunst, frankfurt/m. , - . . adorno , p. , translation: j.g. . this is a central theme in seel , ff., ff. . there is an asymmetry here that we need to be aware of: while an element of beauty inheres in the sublime, beauty—especially in the second sense—can exist without any admixture of the sublime. . haneke and assheuer , f. references adorno, th. w. . minima moralia. frankfurt/m.: suhrkamp. haneke, michael, and thomas assheuer. . nahaufnahme michael ha- neke. gespräche mit thomas assheuer. berlin: alexander verlag. seel, martin. . eine Ästhetik der natur. frankfurt/m.: suhrkamp. . . “von ereignissen.” in paradoxien der erfüllung. philosophi- sche essays. frankfurt/m.: suhrkamp. . . “Über den kulturellen sinn ästhetischer präsenz—mit sei- tenblicken auf descartes.” in die macht des erscheinens. frankfurt/m.: suhrkamp. university of east london institutional repository: http://roar.uel.ac.uk this paper is made available online in accordance with publisher policies. please scroll down to view the document itself. please refer to the repository record for this item and our policy information available from the repository home page for further information. to see the final version of this paper please visit the publisher’s website. access to the published version may require a subscription. author(s): humm, maggie. article title: beauty and woolf year of publication: citation: humm, m. ( ) ‘beauty and woolf’ feminist theory ( ) - link to published version: http://dx.doi.org/ . / doi: . / publisher statement: http://www.uk.sagepub.com/authors/journal/permissions.sp information on how to cite items within roar@uel: http://www.uel.ac.uk/roar/openaccess.htm#citing beauty and woolf writing to her lover vita sackville-west in , virginia woolf facetiously refused to define beauty other than by associating beauty with prose, ‘i write prose; you poetry. now poetry being the simpler, cruder, more elementary of the two…can’t carry beauty as prose can. very little goes to its head. you will say, define beauty – but no: i am going to sleep’ (woolf, : ) ( ). but discussions about beauty had kept virginia and her sister vanessa in a ‘twitter of excitement’, when young women, at their thursday evening soirees in gordon square (woolf, : ). ‘vanessa… incautiously used the word “beauty”. at that, one of the young men would lift his head slowly and say, “it depends what you mean by beauty.” at once all our ears were pricked. it was as if the bull had at last been turned into the ring’ (woolf, : ). woolf’s writings contain differing but specific ideas about gender and beauty, including distinctions between natural and creative beauty, the ethics of beauty, the relationship of writing and beauty, the beauty of places, as well as accounts of women judged by woolf to be beautiful and a misapprehension that she herself lacked beauty. woolf’s overriding opinion throughout her life was that ‘beauty is not the note of our great men’ (woolf, b: ). what interests me in woolf’s understandings of beauty is how often woolf triangulates mothers, beauty and the body, particularly in her autobiographies and the novels to the lighthouse and the voyage out. this strategy could be read as a partial feminist reproof to a conventional binary in which beauty is the passive feminine to be contemplated by a male observer, as some of woolf’s contemporaries suggested (woolf, and ). unlike woolf, i shall argue, contemporary feminist theory has inadequately addressed the notion of a non specular beauty as an alternative to that tradition. feminist theory has focussed, in the main and for too long, on theories of the body in a legitimate reaction to a masculine coupling of beauty with a female or idealized maternal body and the sublime with male creativity. although a resisting approach to aesthetic objectification is always necessary, there have been few productive feminist accounts of female or maternal beauty. woolf’s writings about beauty, mothers and the body, if read through the lens of post-lacanian theory – particularly the work of luce irigaray and bracha lichtenberg ettinger, offer a moving and positive feminist account of women and beauty. rather than representing the beauty of mothers only visually for other characters and the reader, woolf gives the maternal body somatic depth and visceral beauty. in addressing the issue of beauty and gender in relation to the body, one is immediately struck by how, in the past decades, there has been little positive feminist attention to beauty, nor the development of appropriate critical methodologies for analysing representations of beauty ( ). instead feminists have devoted much of their attention to the body ( ). lynne pearce accurately notes that this overwhelming attention to the body coincides with the ‘rise of post-structuralism’ (pearce , ). a more long-term view might add that feminists are determined to separate beauty from the body and underplay the utility of a feminist concept of beauty perhaps for the very good reason that masculine philosophies and art histories have for so long negatively conflated ‘woman’ and ‘beauty’ in a gendered binary in which an active masculine sublime is opposed to a passive feminine beauty (battersby, ). french feminist philosophers have deconstructed these gendered binaries structuring western philosophies and the traditional coupling of superior, active epithets with masculinity and inferior passive epithets with femininity (cixous, ). in such binaries all paradigms of women’s ‘beauty’ can be only analogical proof of man’s interpretative skills. for example, depictions of beauty, from wordsworth to freud, associate creativity and culture with a masculine domain and the female body with matter. certainly many masculine philosophies exemplify cixous’s critique. from edmund burke’s opposition of the smallness and purity of beauty to the wild sublime, immanuel kant’s blending of beauty and sentiment and g. w. f. hegel’s merging of beauty, truth and goodness, western conceptualisations of beauty are dominatingly gendered, not least by umberto eco himself in his recent collection of their work (eco, ). cixous and other feminists have made devastating critiques of this western misogyny and its notion of a masculine contemplation of a dependent feminised beauty (jardine, ). but an alternative feminist theory of beauty has not emerged. from laura mulvey’s germinal essay, ‘visual pleasure and narrative cinema’ onwards, deconstructions of the ‘beauties’ of visual pleasure (because such pleasures involve a masculine objectifying gaze) have meant that questions about the relations between women’s beauty, the body and pleasure, and writers’ and artists’ take on these, become almost impossible questions (mulvey, ). the feminine cannot be beautiful but is either a ‘masquerade’ or a ‘performance’ and beauty is in most cases certainly suspect because ‘beautiful women’ are socially constructed emblems of patriarchal society (modeleski, , butler, ). in undoing gender judith butler explains that because it is ‘through the body that gender and sexuality become expressed’ and ‘inscribed by cultural norms’ that ‘the most important task is to think through the debates on the body’ (butler , and ). while new technologies of the body, whether surgical, medicinal, or physiological may create, as butler hopes, ‘new forms of gender’, this decoupling of beauty and women’s bodies focuses too much attention to the body at the expense of attempts to define beauty’s affect and provenance. a glance at one decade of feminist theory endorses the salience of this generalisation. in a major collection of new feminist criticism indexes beauty only twice under ‘as a commodity’ and ‘old (er) women’, whereas the body has over forty references and is granted agency ‘as a battleground’ and ‘performative’ ( frueh, langer, raven, ). a decade later in the feminism and visual culture reader similarly still contains only one reference to beauty and over one hundred page references to the body (jones, ). there are probably many reasons for this occlusion but together with butler’s argument, another major cause might be the predominance of psychoanalytic theory within feminist thinking and analyses since the s. psychoanalysis theorizes identity in relation to sexuality and necessarily therefore focuses on the body. feminist cultural critics analysing constructions of femininity and consumption provide a partial corrective to this neglect. arguments for the possibility of a female flaneuse enjoying the scopic pleasures of gazing at beautiful products and beautiful women in modernity, whether in department stores or cinemas, productively describe women’s spaces in urban modernities (friedberg, , parsons, ). but such analyses are far from celebratory nor adequately address an aesthetics of modernity that could involve tropes of beauty. nor is the work of manufacturing women’s beauty through the acquisition of material products particularly progressive. feminist unease with debates about beauty curtails searches for the rules of beauty’s production, consideration of its affects and how we might apprehend and analyse these in texts. what is occluded in the sophisticated scholarship on the body is a working concept of female beauty and the body not in terms of what can or cannot be symbolized - that is, represented in performances, sexualities and constructions - but as an aesthetic inscription of embodiment in the feminine. luce irigaray’s theories of beauty the question remains: how might feminists engage with ideas about beauty and women’s bodies and the maternal more productively rather than deconstructing, however brilliantly, masculine fetishizations of beauty? luce irigaray’s essay ‘how can we create our beauty?’ is a helpful starting point (irigaray, ). as a psychoanalyst herself, irigaray focuses on sexual identities but does not allow sexual difference a grounding purpose. she does, however, wish to ‘help women exteriorize in their works of art the beauty, and the forms of beauty, of which they are capable’ (irigaray, : ). irigaray’s writings on women’s bodies have received a great deal of attention and much debate over recent years. rosi braidotti’s sophisticated analysis in patterns of discourse notes the ambiguity of irigaray’s position at ‘the very heart of masculine logic’ and the possible dangers of irigaray’s tactic of mimesis, but braidotti concludes that irigaray’s defence of ‘mother-daughter love’ and this ‘new metaphorical system’ is a ‘significant step’ (braidotti, : - ). in other words, rather than being ‘utopian’, as toril moi mistakenly asserts, irigaray’s exploration of mother-daughter love can provide an ontological way of establishing an aesthetic of corporeal existence (moi, : ). in this brief essay on beauty irigaray argues that women’s bodies can have a ‘morpho-logic’. ‘we can and must accomplish it as a woman’s and a mother’s contribution to not only the natural but also the spiritual life of the world’ evident in ‘the beauty of our works’ [unspecified] as ‘medium’ (irigaray, : ). irigaray calls for beautiful representations that will refuse to separate ‘mothers from daughters’ in ‘color’ that ‘expresses our sexuate nature’ and ‘spiritual values’ (irigaray, : and ). irigaray’s rather condensed argument here appears almost metaphysical. irgaray does argue that the two sexes can be represented by different colours. this claim follows her earlier figuration of red blood linked to matrilineal descent and white blood as patrilineal in speculum of the other woman (irigaray : ). in some ways irigaray’s claim matches a similar approach to colour by vanessa bell the artist and woolf’s sister. bell certainly utilised specific colours in a gendered way, for example, associating blue with the maternal as in renaissance paintings. writing retrospectively to roger fry about colour and modernism, bell claimed, ‘it seems to me there was a great deal of excitement about colour then – or years ago…i suppose it was the result of trying first to change everything into colour’ (bell : ). in ‘on the maternal order’ irigaray goes on to specifically attack any ‘blindness to the processes of pregnancy’ and suggests that the mother-child symbiosis is a ‘gift of generosity, abundance and plenitude’ (irigaray, b: - ). woolf’s ideas of beauty virginia woolf’s discussions of beauty and her encapsulation of these ideas within tropes of mothering and the body offer an interesting example of some of irigaray’s themes. certainly woolf, too, felt beauty as colour. ‘as a writer, i feel the beauty, which is almost entirely colour, very subtle, very changeable, running over my pen’ (woolf, : - ). and woolf’s understandings of her own symbiotic relationship with her dead mother julia stephen are located in what we might term the semiotic in kristeva’s terminology (kristeva ). ‘how did i first become conscious of what was always there – her astonishing beauty? perhaps i never became conscious of it’ (woolf, c: ). after julia’s early death at forty-nine when woolf was thirteen, woolf felt that ‘she has always haunted me, partly, i suppose, her beauty’ (woolf, : ). woolf’s to the lighthouse and the voyage out are imbued with a beautiful, melancholic lost mother and both novels figure an epistemology of the bodily intertextualities of mothers and daughters, as if woolf is working through the traces of the mother as borderlinked other. ( ) woolf also felt that her sussex and london homes carried particular and somatic connotations of beauty. woolf’s descriptions of rodmell’s landscape and london streets illuminate but also create beauty as a living study. ‘rodmell…how the beauty brimmed over me & steeped my nerves till they quivered, as i have seen a water plant quiver’ (woolf, : ). in the countryside ‘beauty abounding & superabounding so that one almost resents it, not being able of catching it all’ ( woolf, : ). in london ‘the bloomsbury squares always intoxicate me with their beauty’ (woolf, : ). and the loved place of her childhood home in st. ives, cornwall still intoxicates woolf as an adult: ‘as for the beauty of this place, it surpasses every other season’ (woolf, : ). the perception of beauty that woolf experiences when returning to greece in the thirties is engendered precisely because greece triggers memories of st. ives as well as of sapphism. greece has ‘agile, athletic beauty…and i could love greece, as an old woman, so i think, as i once loved cornwall’ (woolf, : ). ‘if ever i had a turn towards sapphism it would be revived by the carts of young peasant women’ (woolf, b: ). if woolf’s descriptions of natural beauty appear to utilise a romantic vocabulary, this does not constrain woolf’s more complex exploration of beauty in modernity. in cinema, that quintessentially modern form, on which woolf wrote the first british avant-garde essay, we ‘open the whole of our mind wide to beauty’ (woolf, c: ). like her sister vanessa bell’s paintings, woolf’s characterisation of the beautiful novel of the future, in ‘the narrow bridge of art’, is resolutely modernist. ‘it will give, as poetry does, the outline rather than the detail’ (woolf, : ). rhoda in the waves might also be describing bell’s paintings ‘i find faces rid of features, robed in beauty’ (woolf, : ). because it lacks a specific project, woolf’s ethics of beauty - ‘beauty is only two fingers breadth from goodness’ - again might be misread as a hegelian vision of spiritualized nature but woolf’s ethics is crucially embodied. woolf also never divorces beauty from materiality and class, joking, for example, that ‘five hundred a year is considerably more valuable that beauty or rank’, but is also pleased that ‘new chairs. and comfort everywhere’ means ‘some beginnings of beauty’ at rodmell (woolf, : and : ). in ‘the mark on the wall’ woolf, as a true modernist, opposes ‘our respect for beauty’ to ‘superstitions’ from the past (woolf, b: ). and, ‘in the modern mind beauty is accompanied not by its shadow but by its opposite’ (woolf b: ). woolf’s perception that ‘beauty is part ugliness’ is what makes her a modern writer, even if she shares walter pater’s notion that such perceptions are likely to be epiphanic visions. beauty is the most common epithet woolf applies to those writers she most admires. in the first volume of woolf’s collected essays it is ‘the beauty, the complexity of her scenes’ that illuminates jane austen; woolf thinks that the ‘beauty’ of george eliot is in eliot’s first publications; while thomas hardy has passages of ‘outstanding beauty and force…in every book he wrote’ (woolf, : , , ). but in her own writing woolf felt that if she tried to ‘get a little more beauty into this one’ [night and day] she risked spoiling the ‘originality’ (woolf, b: ). later woolf happily ‘burst out in ecstasy at your [ethel smyth] defence of me as a very ugly writer…how could i write beautifully when i am always trying to say something that has not been said…so i relinquish beauty, and leave it as a legacy to the next generation’ (woolf, d: ). in three guineas woolf advances her most feminist expression of beauty. the women-only outsiders society dispenses with masculine ‘pageantry not from any puritanical dislike of beauty’ but ‘to increase private beauty; the beauty of spring, summer, autumn’ and ‘every barrow in oxford street’ (woolf, : ). and the most beautiful women are, to woolf, her half-sister stella duckworth, her sister vanessa and her mother julia stephen. stella duckworth, woolf’s surrogate ‘mother’ after the death of julia, ‘developed her own beauty’ and with julia ‘their beauty was the expression of them’ (woolf, d: ). after stella’s sudden early death in pregnancy, vanessa took on stella’s role as a ‘mother’ to woolf and ‘had much of the beauty’ [of stella] and ‘was also, on her secretive side, sensitive to all beauty of colour and form’ (woolf, d: - ). in woolf’s first collection of letters she extols vanessa’s beauty, vanessa’s name ‘contains all the beauty of the sky’ (woolf, : ). vanessa’s beauty is always corporeal to woolf. ‘she looks best undressed. we talk a great deal about beauty and art’ (woolf, : ). woolf is emotionally forthcoming when writing directly to vanessa: ‘how i adore you! how astonishingly beautiful you are! no one will ever take the winds of march with beauty [a reference to the winter’s tale] as you do’ (woolf, : ). woolf repeats the phrase to vanessa’s daughter angelica: ‘thank god you haven’t an elder sister to take the winds of march with beauty, as i had, and so force you to be a modest violet’ (woolf, : ). from her birth, angelica was also, to woolf, ‘a whirlwind of beauty’ (woolf d: ). about her own appearance woolf is often self-derogatory. as anne olivier bell, the wife of woolf’s nephew quentin bell and editor of woolf’s diaries, suggested when unveiling woolf’s statue in tavistock square in : ‘i was at first reluctant to collude in the public exposure of her image, knowing how she disliked being stared at’ (bell, : ). forced by her husband leonard woolf to eat more food, because leonard thought that a weight increase would obviate woolf’s depressions, at nine and a half stone woolf felt that she had parted ‘with youth and beauty’ (woolf, b: ). by , ‘for my own part, a little beauty is what i crave; anybody can be good; wits i have myself’ (woolf, : ). the next year in , woolf felt that ‘my own lack of beauty depresses me’ and after being ‘bingled’ (shingled) by the hairdresser mr cizec, she was certain that ‘i am short haired for life. having no longer, i think, any claims to beauty’ (woolf, : and ). the maternal and to the lighthouse woolf thought her mother to be ‘not only the most beautiful of women as her portraits [by burne-jones and other artists] will tell you, but also one of the most distinct’, and that julia created unthinkingly ‘a certain silence round her by her very beauty’ (woolf, d: ). woolf characterises julia’s beauty as explicitly maternal. julia’s maternal image is foregrounded in woolf’s autobiographical writing, ‘a sketch of the past’, with the mother as semiotic origin in a matrix of sounds, smells and colours of pure jouissance in the often quoted opening passage. ‘red and purple flowers on a black ground – my mother’s dress; and she was sitting either in a train or in an omnibus and i was on her lap. i therefore saw the flowers she was wearing very close…it is of hearing the waves breaking…it is of lying and hearing this splash and seeing this light, and…feeling the purest ecstasy i can conceive’ (woolf, c: - ). the description exactly matches a photograph of julia with virginia on her lap aged three that is plate f in woolf’s father’s photo album (humm, ). woolf has to re-create her mother’s beauty again and again in writing about the body because, as irigaray argues, ‘the materiality of the relationship [of the daughter] to this maternal body having disappeared, language remains an inexhaustible “womb” for the use that’s made of her’ (irigaray, b: ). this tense relationship between a body of writing and her mother’s nurturing, maternal and beautiful body, is frequently negotiated by woolf through the symbolization of a maternal presence; for example, both in the figure of helen in the voyage out as well as in the gender fluidities of orlando (woolf, ). the major metaleptic figure in woolf’s to the lighthouse is the figuration of woolf’s memories of her mother, julia stephen, as mrs. ramsay and woolf adopts an intense mode of sensual symbolization to capture the maternal presence and absence. in this novel woolf’s need to depict the maternal body as beautiful shapes her choice of scenes, particularly the famous dinner of boeuf en daube, as well as the texture and conclusion of the novel, when lily completes her beautiful modernist painting of mrs. ramsay. the beauty of mrs. ramsay powerfully affects every character in the novel. her guest mr. bankes sees mrs. ramsay’s beauty as being like a madonna: ‘mother and child…in this case the mother was famous for her beauty’ (woolf, : ). the narrator endorses this perception: ‘she bore about with her, she could not help knowing it, the torch of her beauty’ (woolf, : ). lily pictures mrs. ramsay always ‘sitting up there with all her beauty opened again in her’ (woolf, : ). mr. ramsay agrees ‘she was astonishingly beautiful. her beauty seemed to him, if that were possible, to increase’ (woolf, : ). woolf’s deictic construction of the mother and the primal loss of the mother in to the lighthouse ends on a hallucinatory moment of lily’s unity with mrs. ramsay in art, ‘with a sudden intensity, as if she saw it clear for a second…i have had my vision’ (woolf, : ). sight becomes vision when lily’s mourning for the lost mother becomes a new creation. it is as if woolf aims to extend sensation beyond what the visual sense seems literally to behold. as claire colebrook acutely notes, ‘we can now read the style of the entire novel in terms of a refusal of the position of subject and object’ (colebrook : ). in the famous, and very long, boeuf en daube scene in to the lighthouse, where mrs. ramsay harmoniously brings together all the characters around a dinner of what was woolf’s friend roger fry’s favourite dish, woolf represents her as a maternal archetype. ‘the whole of the effort of merging and flowing and creating rested on her [against]… the sterility of men’ (woolf, : ). the body of the stew is a referent for mrs. ramsay’s maternal body. ‘a soft mass…with its shiny walls…a french recipe of my grandmother’s said mrs. ramsay’ (woolf, : ). the beauty and sensuality of the moment is in ‘female time’, as the womb like quality of the stew pot is matched in its maternal quality by mrs. ramsay’s intuitive ability to decode the emotional affects of each character’s body language. this ‘maternal quality’ has been characterised by bracha lichtenberg ettinger as the ‘matrixial’ (ettinger ). bracha lichtenberg ettinger the contemporary post-lacanian psychoanalyst ( ) and artist bracha lichtenberg ettinger similarly focuses on aesthetic reconstructions of intra-uterine maternal affects in what she terms the `matrixial gaze’ the title of her major work (ettinger, ). ettinger’s theoretical project is to develop ways of understanding a feminine subjectivity and space within the symbolic, by re-creating the pre-birth psychic structuring we all experience. in her contribution to inside the visible, the s most significant exhibition of women’s art, ettinger argues that `the with-in-visible matrixial screen is a web into which subjectivity is woven in different ways in art – by trauma, by phantasy, by desire. it is in between us, it is a veil spread between joint traumas, fractions of phantasy from out into the inside and aspects of painting in-to the outside. on the screen’s interlaced threshold, a feminine gaze diffracts’ (ettinger, : ). elsewhere, bracha lichtenberg ettinger lays bare the psychic mediations which lie between the maternal imaginary and external objects, and which are visible in beautiful artistic representations (humm, ). `the emotional and mental conductivity of an artwork may reflect on far away matrixial unconscious events’ (ettinger, b: ). the intrauterine event-encounter, in other words, can be re- traced in art and writing. what post-lacanian feminism offers is a more positive way of understanding both the imaginary and the maternal - for example, in the notion of a trans-subjective figuration. bracha lichtenberg ettinger’s theorisation of the imaginary recreates a lost maternal object and lost matrixial relationship in painterly, poetic and photographic images. this does seem to offer a way of conceptualising beauty and the maternal that makes available a female imaginary in the symbolic and avoides the false division between beauty and the body in much feminist writing. griselda pollock argues that the maternal haunts our aesthetic subjectivities, not as in the manner of lacan’s mastering gaze, but as `a borderline awareness’ (pollock, : ). as griselda pollock suggests, in her many rich accounts of ettinger’s work, `strategies of representation in the visual arts, from painting to photography and film, have been institutionalised to lure our gaze and suture our desire to that which the culture wishes to fix us’. pollock argues that `ettinger’s method permits a glimpse of another kind of vanishing point a matrixial gaze’ which is distinct from the usual `confrontation between practice and popular cultures’ (pollock , ). the characteristics of such a method resemble woolf’s modernist experiments: a use of fragmentary images, a refusal sometimes of nominative sentences, for example, a fluidity of narrator, a confusion of characters with objects, interruptions of linearity, traces of the imaginary and intricately worked surfaces. in the lacanian symbolic `woman’ is identified only as the unknown, the objet a of archaic sensuality lost, as it were, when we enter the symbolic, but in ettinger’s art, pollock argues, the objet a `may in art achieve a borderline visibility’ (pollock, : ). in this way the matrixial is not placed in opposition to, or anterior to, the phallic but opens up the symbolic field to a feminine dimension, to an idea of beauty that is not the western masculine objectified and passive contemplation of feminine beauty. bracha lichtenberg ettinger argues that, in opposition, art can `create differences in the transmission’ and posit new symbols in traces of subjectivity, descriptions which `indicate and elaborate traces of an-other real’ (ettinger, : ). as pollock argues, `this theorisation has many facets and radically realigns the way we think about the process of making and seeing painting [beauty], at the same time it offers a radical contribution to the theorisation of femininity, not as the other of masculinity’ (pollock, : ). woolf also delighted in frequently describing the textual birth of her novels and non -fiction in terms of matrixial creativity. writing three guineas in march was, for woolf, a hypotyposis of childbirth. ‘the mildest childbirth i ever had...no book ever slid from me so secretly & smoothly’ (woolf, : - ). as ettinger suggests, maternal affects and sensations can be elevated into significations of great theoretical and beautiful significance. what is particularly helpful for studies of woolf is that reading woolf through a post-lacanian lens allows for a richer understanding of how her depictions of female bodies are intertwined with a redemptive vision of beauty and the maternal. such a reading refuses the many negative critiques of woolf that focus only on the body rather than on this more complex nexus. woolf’s representations of the body and her understandings of her own body have often been a negative focus of bloomsbury, feminist and modernist criticism. initially, woolf was described by biographer nephew quentin bell, her friend the novelist e. m. forster and her husband leonard woolf, as ‘outside’ her body, as ethereal and unworldly (bell, ). in these readings woolf’s body is a sign of alterity, couched in tropes of neglect and absence. subsequent discussions of woolf as an anorexic, as dis-eased in her body and as possibly abused by her half brothers gerald and george duckworth, have yielded significant insights into woolf’s writings and symbolizations (de salvo, ; glenny, ). there are now agreed assumptions among some feminist critics about the ways in which woolf’s apparent struggles with her weight, eating and dressing, possibly initiated by her psychosomatic refusal of her brothers’ abuse, animate woolf’s discursive representations as well as her life narrative. but it is important to note that disorded eating is not an eating disorder. this critical consensus locks woolf too firmly into a body. woolf is praised as if she is a proto-feminist for either refusing cultural constructions of the feminine body or for revealing a so-called somatic victimhood. in these readings the body represents dissolution. for example, ros peers argues of the voyage out that rachel ‘has no sense of boundaries’ and displays the classic characteristics of anorexia: ‘she has no coherent sense of herself’ (peers, : ). the voyage out in the voyage out, just as in to the lighthouse, woolf realises what teresa brennan calls, in a summative account of affect, the beautiful ‘living logic of the mother’s flesh’ as a ‘shield against the negative affects’ (brennan, : ). woolf makes the beautiful maternal figure imaginatively present and absent, both alive and dead in her novel, and her characterisation of the beautiful morphology of the maternal body, in her letters, diaries and novels, is intense. in the voyage out the absence of a mother and rachel vinrace’s need to register the older helen as a maternal figure is very marked. helen is perceived as an intensely beautiful maternal figure, not only by rachel but also by other characters. ‘her beauty, now that she was flushed and animated, was more expansive than usual, and both the ladies felt the same desire to touch her’ (woolf, : ). helen also possesses a beautiful voice. ‘the broken sentences had an extraordinary beauty and detachment in hewet’s ears’ (woolf, : ). again, ‘the extraordinary and mournful beauty of her attitude struck terence’ (woolf, : ). but it is the semiotic beauty of helen and rachel’s relationship that dominates the novel. it is helen who cares for rachel in rachel’s severe illness and subsequent death. ‘helen was here and helen was there all day long’ (woolf, : ). clive bell, woolf’s brother-in-law, thought that woolf had ‘invented some new, undream’t of form’ (bell, : ). in contemporary critical vocabulary, that ‘new form’ might represent rachel’s submission to the power of the mother and her experience of jouissance: ‘helen’s form stooping to raise her in bed appears of gigantic size…her body became a drift of melting snow, above which her knees rose in huge peaked mountains of bare bone’ (woolf, : ). in this ‘psychotic’ speech, full of metaphor and metonymy, rachel is un-assimilable to standard medical treatment. it is as if helen haunts rachel in hallucinations. vanessa curtis argues that rachel’s character has attributes of woolf’s half-sister stella duckworth (for example, both die at three o’clock) that suggest further familial resonances (curtis, ). but it is also of crucial significance for understanding woolf’s characterisation of the maternal figure that the empathy between mother and other was the speciality of woolf’s mother julia stephen. critics have explored the possible impact of woolf’s mother’s lack of physical contact with her daughter, having to care, as julia did, for eight children, her own mother and husband, and other relatives as well as the well-being of large numbers of local people in st. ives the stephen’s holiday home (desalvo, ). this much commented on representation of julia as the absent mother explains woolf’s turn to hyotyposis and other metaphorical devices in her fiction. what has been occluded is an examination of julia’s own writing, writing which woolf knew well. julia stephen’s notes from sick rooms, privately printed in , the year after woolf’s birth, presages not only the physical descriptions in the voyage out but also woolf’s techniques of empathetic narrators and sometimes exaggerated sensibilities (stephen ). indeed woolf’s first biographer winifred holtby noted the similarities of ‘peculiar humour, consisting of a mixture of irony and extravagance’ in both stephen’s pamphlet and woolf’s writing (holtby, : ). julia stephen was not a public writer, publishing only notes from sick rooms, an essay for her husband’s dictionary of national biography about her great aunt julia margaret cameron the famous victorian photographer, and a few other essays, as well as signing mrs. humphrey ward’s notorious appeal against female suffrage, published in the nineteenth century in . ward’s lengthy attack on feminism, and julia’s support of it, is usually cited as an example of julia’s victorian ideology with which woolf had to battle. but what is true of the appeal and fascinating about notes from sick rooms is the characterisation of the maternal in both. the special knowledge of women and the ‘habitual affective disposition and quickness to feel’ is one of the ‘peculiar excellencies of women’ particularly in ‘the caring of the sick’, which gives women ‘larger and more extended powers’ (ward, : ). equally in notes from sick rooms stephen validates women’s special knowledge of nursing as a beautiful, affective experience. the sick room is a room of women’s own since both patient and nurse are female and the good nurse will, stephen suggests, have an almost empathetic, affective relation with the patient as if being able to feel and visualize from her perspective, exactly like the descriptions of helen and rachel in the voyage out. ‘in doing the invalid’s hair, the nurse…shall hold the hair near the roots with one hand…lightly touch’ and be aware that ‘few things are more aggravating’ for the patient than to ‘have a long hair brought slowly over the face each time the brush comes around’ (stephen, : ). this dyadic union of female patient and mothering nurse is marked by the way in which the nurse carries the other’s negative affects, allowing affects, as brennan suggests, ‘to pass from the state of sensory registration to a state of cognitive or intelligent reflection’ (brennan, : ). a nurse’s hand must always have ‘the palm hollowed inwards a little’ to curve to the patient’s ‘hand and cheek’ (stephen, : ). in the voyage out, helen’s similar introjected identifications enable helen to instantly understand rachel’s distress. ‘when helen came in an hour or two later, suddenly stopped her cheerful words, looked startled for a second and then unnaturally calm, the fact that she [rachel] was ill was put beyond a doubt’ (woolf, : ). there are great similarities between julia’s descriptions of the mothering nurse and woolf’s continual turn to maternal presences in woolf’s use of metaleptic metaphors. woolf’s knowledge was a matrilineal inheritance. julia’s own mother maria jackson, woolf’s grandmother, was the wife of a physician and in their letters maria and julia deploy very accurate medical terminology (adolph ). in maria wrote to julia about a servant on leave ‘that her sister is going into hosp[ita]l to undergo an operation that the tumour is in the womb so that i suppose it is ovarian’ (adolph, : ). grandmother, mother and daughter share an investment in discursive representations of the beautiful, nurturing, maternal body. conclusion virginia woolf’s evocation of the maternal body, and the association woolf makes between beauty and the maternal, offer one literary model of conceptualising beauty without incurring objectifications. the implication here drawn from woolf’s writings is that beauty is not necessarily ‘owned’ by the symbolic nor that representations are only possible through the symbolic, but that these representations can occur in a more fluid way. the ongoing affect of woolf’s maternal images emerge, not as fixed tableaux, but as a shared jouissance. woolf’s focus on the beauty of the maternal attests to the possibility of a matrixial modernism in modernity. some feminists see modernism as involving a spurning of beauty. wendy steiner, in venus in exile, argues that modernism aimed to destroy beauty and that ‘the perennial rewards of aesthetic experience – pleasure, insight, empathy – were largely withheld, and its generous aim, beauty, was abandoned’ (steiner : xv). steiner goes on to claim that modernism equated truth with ugliness and replaced ‘the beauty of woman with the beauty of form’ (steiner : ). venus in exile takes a resisting reader approach to modernism in a trajectory through to postmodernism, including an unconnected chapter about the national book critics circle award for fiction of which steiner was one of the judges. yet steiner omits consideration of key modernist events including the armory show and the two post-impressionist exhibitions or bloomsbury modernism, nor does she define an aesthetic of beauty except to cite the paintings of pierre bonnard. in a more scholarly book, the modernist cult of ugliness, lesley higgins shares steiner’s revisionist approach. higgins constructs a reductive notion of modernism in order to attack the modernist canon of ezra pound, wyndham lewis and t. s. eliot among other writers. although the modernist cult of ugliness contains fascinating research on public debates about beauty for example, the whistler/ruskin trial, higgins’ version of modernism is as narrow as steiner’s. also ignoring art exhibitions, higgins argues a well-worn theme that the ‘emancipation of male modernists was made possible, initially, by textual and sometimes personal discriminatory practices’ (higgins : ). certainly pound advocated ‘ugliness’ in his essay ‘the serious artist’ but exploring, yet again, pound or eliot’s ‘gendered identity crises’ does not advance the generous broadening of the parameters of modernism by rita felski and critics of new modernism (pound ; higgins : ; felski ). equating modernism’s violent transgression of previous cultural norms with ugliness is problematic – for example, it ignores modernism’s attention to classic greek culture. virginia woolf’s modernism complicates this version of a masculinized aesthetic (goldman ). in her writing woolf creates a specifically feminine yet sometimes violent ethics of beauty, lodged in the maternal, and free from specularisation and objectifications. woolf’s depiction of the affects of beauty and the maternal, like vanessa bell’s depiction of the beautiful maternal phantasmagoric space of studland beach, connects a modernist aesthetic with new ways of life, for example, validating a domestic ethics. but woolf’s maternal modernism never denies the values of progressive enlightenment. as mrs. thornbury (one of woolf’s typically wise old mothers) hopes, at the conclusion of the voyage out, she will not die without seeing ‘the changes, the improvements, the inventions – and beauty’ of the future ( ). i am grateful to the editors for their acute comments on an earlier version of this essay. notes . of course, woolf was aware of modernist poetry’s cultural prestige. on the publication of the oxford book of modern verse edited by w. b. yeats, woolf noted in her diary ‘yeats’ anthology out. am i jealous? no: but depressed to feel i’m not a poet’ (woolf, : ). . for example, apart from rosemary betterton’s sophisticated work on maternal embodiments and beauty (betterton, and ), many feminists, like germaine greer, argue that aesthetic concepts of women’s beauty are inflected by the masculinity of aesthetic philosophy (greer ). other work in this field largely focuses on the economy of beauty (willett, ); on racialized beauty (gilman , rosenthal ); on beauty and social constructions (brand , psomiades ); on the twentieth century’s troubled relationship with beauty (steiner ) and body building and eroticism (freuh ). although the british association of art historians did address beauty in the renaissance at its conference (ames-lewis and rogers, ), since then beauty has figured only as one of twenty-three panels at the conference ‘body and soul’ and here only in terms of representations of physical cultures. . the major feminist critiques of the body include gallop ( ) bordo ( ) tasker ( ) braidotti ( ) grosz ( ) gatens ( ) shildrick ( ) prosser ( ) weiss ( ) and ahmed and stacey ( ). both scarry ( ) and prosser ( ) offer crucial, systematic critiques of the body. a special issue of differences. : fall was ‘the question of embodiment’. . woolf’s writings about beauty do not contain one single message. for example, some of woolf’s comments about beauty elsewhere in her work could be read as somewhat kantian because woolf appears to share kant’s belief, in his critique of judgement that ‘natural beauty is a beautiful thing; artistic beauty is a beautiful representation of a thing’ (kant, : ), as well as sharing the romantics’ perceptions of beauty in their blending of passion and sentiment. in her short story ‘the introduction’, woolf does suggest that pure beauty exists ‘without any care whatever what human beings thought’ (woolf, : ). . post-lacanian feminism is an umbrella term applied to the work of a number of contemporary psychoanalytic thinkers including the french feminist luce irigaray as well as bracha lichtenberg ettinger. the premise of post-lacanian feminism is that lacan creates in his writing an impossible binary between phallic language and that maternal body, and that feminism needs to go beyond (post) lacan (campbell, ). as jan campbell suggests in arguing with the phallus, `the symbolisation of the daughter’s imaginary in terms of the mother remains an impossibility’ for lacan, whose concept of an imaginary is based `entirely on a masculine and phallic morphology’ (campbell, : ). references adolph, a. 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( c) ‘the cinema’, pp. - in the essays of virginia woolf: volume - . (ed) a. mcneillie. london: the hogarth press. woolf, v. ( d) a reflection of the other person: collected letters - . (eds) n. nicolson and j. trautmann banks. london: the hogarth press. wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ helen salisbury: small is beautiful primary colour helen salisbury: small is beautiful helen salisbury gp oxford this week i learnt that gp surgeries closed their doors for the last time in . some of the practices merged, some doctors were employed or became partners elsewhere, and some gps, wearied and defeated, took early retirement. most of the practices affected were small, with lists of fewer than patients. it’s easy to see why smaller practices are vulnerable. a single retirement or episode of ill health can be enough to close a practice if it can’t recruit new staff. the ever increasing regulatory burden on primary care is harder to bear if you have only two partners and a part time practice manager. larger, merged practices may be more resilient in the face of change, and there are some economies of scale, especially in administration. the direction of travel for general practice seems to be towards ever bigger organisations—through networks, super-practices, or corporately owned chains. when considering the benefits of scale, it’s also worth asking what we risk losing. patients may lose a place that they know and where they are known. where once they walked to the surgery and greeted the receptionist by name, now they take a bus and see a new face on each visit. they’re also less likely to see the same doctor. this loss of relational continuity isn’t just about how patients feel—although familiar places and people probably make it less stressful to seek help and advice. we know that seeing the same doctor at most appointments reduces the likelihood of an avoidable hospital admission, especially among patients who consult frequently. this makes sense: if i know that my breathless patient also has anxiety but actually his chest is no worse than two weeks ago, i can reassure him confidently. it’s not only patients who risk losing something important in the rush for scale. many gps chose their speciality because it offered a chance to treat people, not just diseases, and to come to know their patients over time. a particular satisfaction comes from treating whole families over many years: relationships deepen, trust grows, secret fears are shared, and you go the extra mile willingly for your patients. i admit to being an idealistic, old fashioned gp who wants to know what makes my patient tick, to recognise when something’s wrong, and to know what’s most likely to help each one. if i worked shifts in the extended hours service i’m confident that i could be a safe and efficient dispenser of medical knowledge, even an empathetic listener, but i’d be doing only half the job i trained for. if we lose continuity we lose job satisfaction and, with it, our main recruiting tool to general practice. we should be careful. competing interests: see www.bmj.com/about-bmj/freelance-contributors. provenance and peer review: commissioned; not externally peer reviewed. perraudin f. gp surgery closures in uk “hit all-time high” in . guardian may . https://www.theguardian.com/society/ /may/ /gp-surgery-closures-in-uk-hit-all- time-high-in- . barker i, steventon a, deeny sr. association between continuity of care in general practice and hospital admissions for ambulatory care sensitive conditions: cross sectional study of routinely collected, person level data. bmj ; :j . published by the bmj publishing group limited. for permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/ permissions helen.salisbury@phc.ox.ac.uk follow helen on twitter: @helenrsalisbury for personal use only: see rights and reprints http://www.bmj.com/permissions subscribe: http://www.bmj.com/subscribe bmj ; :l doi: . /bmj.l (published june ) page of views and reviews views and reviews o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b m j: first p u b lish e d a s . /b m j.l o n ju n e . d o w n lo a d e d fro m http://group.bmj.com/group/rights-licensing/permissions http://group.bmj.com/group/rights-licensing/permissions http://www.bmj.com/permissions http://www.bmj.com/subscribe http://crossmark.crossref.org/dialog/?doi= . /bmj.l &domain=pdf&date_stamp= - - http://www.bmj.com/ [pdf] beauty and the beast: superconformal symmetry in a monster module | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /bf corpus id: beauty and the beast: superconformal symmetry in a monster module @article{dixon beautyat, title={beauty and the beast: superconformal symmetry in a monster module}, author={l. dixon and p. ginsparg and j. harvey}, journal={communications in mathematical physics}, year={ }, volume={ }, pages={ - } } l. dixon, p. ginsparg, j. harvey published mathematics communications in mathematical physics frenkel, lepowsky, and meurman have constructed a representation of the largest sporadic simple finite group, the fischer-griess monster, as the automorphism group of the operator product algebra of a conformal field theory with central chargec= . in string terminology, their construction corresponds to compactification on az asymmetric orbifold constructed from the torusr /∧, where ∧ is the leech lattice. in this note we point out that their construction naturally embodies as well a larger… expand view on springer theory.uchicago.edu save to library create alert cite launch research feed share this paper citationshighly influential citations background citations methods citations results citations view all citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency monstrous moonshine from orbifolds m. tuite mathematics highly influenced view excerpts, cites background and methods save alert research feed monstrous branes b. craps, m. gaberdiel, j. harvey mathematics, physics pdf view excerpts, cites background save alert research feed monstrous string-string duality s. chaudhuri, d. lowe physics pdf view excerpts, cites background and methods save alert research feed a nonmeromorphic extension of the moonshine module vertex operator algebra yi-zhi huang physics, mathematics pdf save alert research feed generalised moonshine and holomorphic orbifolds m. gaberdiel, d. persson, r. volpato mathematics, physics highly influenced pdf view excerpts, cites methods save alert research feed u-duality and the leech lattice michael rios physics, mathematics pdf view excerpt, cites background save alert research feed super-whittaker vector at c = / p. desrosiers, l. lapointe, p. mathieu mathematics, physics pdf save alert research feed new duality transformations in orbifold theory j. boer, j. evslin, m. halpern, j. e. wang physics save alert research feed fricke lie algebras and the genus zero property in moonshine scott l. carnahan mathematics pdf save alert research feed conformal field theory of twisted vertex operators l. dolan, p. goddard, p. montague physics save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency superconformal invariance in two dimensions and the tricritical ising model d. friedan, zongan qiu, stephen h. shenker physics pdf save alert research feed comments on the algebra of straight, twisted and intertwining vertex operators e. corrigan, t. hollowood physics pdf save alert research feed interactions on orbifolds s. hamidi, c. vafa physics save alert research feed (central charge c) = superconformal field theory l. dixon, p. ginsparg, j. harvey physics pdf save alert research feed atkin-lehner symmetry g. moore physics save alert research feed infinite conformal symmetry in two-dimensional quantum field theory - nucl. phys. b , ( ) a. belavin, a. polyakov, a. zamolodchikov physics , pdf save alert research feed on toroidal compactification of heterotic superstrings. ginsparg physics, medicine physical review. d, particles and fields save alert research feed a natural representation of the fischer-griess monster with the modular function j as character. i. frenkel, j. lepowsky, a. meurman mathematics, medicine proceedings of the national academy of sciences of the united states of america pdf save alert research feed a moonshine module for the monster i. frenkel, james lepowsky, a. meurman mathematics save alert research feed the conformal field theory of orbifolds l. dixon, d. friedan, e. martinec, stephen h. shenker physics save alert research feed ... ... related papers abstract citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue untitled zurich open repository and archive university of zurich main library strickhofstrasse ch- zurich www.zora.uzh.ch year: serotonin in the heart: the beauty and the beast bogdanova, a doi: https://doi.org/ . /j. - . . .x posted at the zurich open repository and archive, university of zurich zora url: https://doi.org/ . /uzh- journal article originally published at: bogdanova, a ( ). serotonin in the heart: the beauty and the beast. acta physiologica, ( ): - . doi: https://doi.org/ . /j. - . . .x f o r p e e r r e v ie w � � � � � � �� !" ��!��#��#�� $�"��% ��&��#�� '�(��)�*��+�,� )�� &�-�� #*�� &�.�� #�� (�+�� /�� *�� *�#��*� ��#�" ��&�� *�� )�� # ! �� acta physiologica f o r p e e r r e v ie w serotonin in the heart: the beauty and the beast existence of a cross-talk between administration of antidepressants targeting serotonin re-uptake and its degradation and heart development in foetus has been acknowledged at a terrible price. the use of selective serotonin reuptake inhibitor (ssri) paroxetine during the first trimester of pregnancy was associated with an increased risk in development of heart defects and late first trimester spontaneous abortions to which severe heart defects contributed (sadler, ). as the importance of serotonin during myocardial development was recognised, pieces of the puzzle began to assemble on multiple actions of -ht in embryonic and adult heart. many of these pieces are still missing. from four classes of serotonin receptors, one ( -ht receptors) is comprised of ligand-gated ion channels, whereas the other three ( -ht / , -ht ad -ht / / receptors) are g protein-coupled receptors. -ht b and -ht receptors are present in the heart. -ht b receptors play an important role in cardiac development during embryogenesis, promoting proliferation and differentiation of cardiomyoblasts (nebigil et al., ). in adult heart this receptor is involved in progression of myocardial hypertrophic remodelling (nebigil and maroteaux, ). -ht receptor controls ca + currents through l-type calcium channels and modulates pacemaker currents in atrial myocytes, and, when hyperactivated, promotes arrhythmia (gergs et al., ). antagonists of this receptor are tested as antiarrhythmic drugs (doggrell, ). apart from receptor-mediated -ht signalling, hydrogen peroxide produced from serotonin during its degradation inside the cells serves as a second messenger or as a damaging pro-oxidant (cooper et al., ). the underlying reactions catalyzed by monoamine oxidases (mao) in the mitochondria of multiple cell types including cardiomyocytes (sivasubramaniam et al., ) are: r-ch nh + o � r-ch=nh + h o r-ch=nh + h o � r-cho + nh although ssris show their beasty look in the first trimester of human life, these drugs appear to give the adult heart a helping hand reducing the risk of myocardial infarction (mi) (sauer et al., ). relief that depressed patients receive after ssris administration contributes to an attenuation of incidence of mi. but this is not all these drugs do. serotonin transporters (serts) in platelets are also supressed by systemic ssri administration. platelets are known to take up peripheral serotonin which is mainly synthesised by enterochromaffin cells in the gut and release it upon activation promoting thereby clot formation. patients on ssris have serotonin-depleted platelets that are not capable of facilitating thrombosis (bismuth-evenzal et al., ). valve cardiomyocytes are also possessing sert {pavone, # }. such a broad range of effects of ssris enables these drugs to protect the heart from mi, whereas other classes of equally effective antidepressants do not reduce the risk of mi (sauer et al., ). unfortunately, preventive treatment against mi is hardly possible. could ssris also be viewed as attractive candidates for reducing myocardial damage in ischemic or post-mi heart? do local increases in interstitial -ht contribute to ischemic heart damage or ischemia-reperfusion injury? the study of sonobe et al (sonobe et al., ) gives us some clues pointing towards active regulation of interstitial serotonin levels in rabbit heart in the course of ischemia-reperfusion in vivo. the authors used microdialysis technique to monitor -ht levels in the interstitial space within the page of acta physiologica f o r p e e r r e v ie w ischemic area of rabbit heart. the impact of -ht production, reuptake and degradation on the maintenance of serotonin balance was assessed in healthy heart, during ischemic insult and after the restoration of coronary blood perfusion. coronary occlusion was associated with a gradual interstitial -htaccumulation. release of the coronary clamp was followed by an immediate dramatic increase in serotonin levels which then declined over the - min of perfusion. re-uptake of -ht actively counteracted its release during reperfusion. degradation of -ht by mao occurred both during the ischemic phase and at reperfusion. these findings let one suggest that inhibition of serotonin re-uptake will keep -ht and a receptors in cardiomyocytes active promoting most likely positive inotropic effects and sustaining contractile function (levy et al., ). however, increased re-uptake of -ht by cardiomyocytes along with restoration of oxygen supply of the heart muscle provides more fuel to mao-a, and aggravates oxidative stress at reperfusion (kaludercic et al., ). thus blocking the sert with ssri including fluoxetine as well as suppressing mao activity during reperfusion may appear to be very beneficial. this therapeutic approach will potentially reduce the risk of re-occluson of coronary vessels as -ht stores in platelets will be depleted and reduce oxidative stress in myocardial tissue at reperfusion rescuing mitochondria from irreversible damage and protecting the tissue from reperfusion injury (ong and gustafsson, ). apart from platelets, vagal afferents, and resident mast cells cardiomyocytes themselves have been recently shown to express their own -ht (ponicke et al., ) and possess their own serotonin re-uptake machinery (pavone et al., ). what is the impact of this source of -ht on the interstitial serotonin pool and if sert and mao inhibition interfere with -ht acting in a paracrine and an autocrine fashion remains to be investigated. the study of sonobe et al. marks the beginning of a long and fascinating journey at the end of which knowledge will be transformed into a new treatment strategy. this new strategy will use the strong sides of ssris avoiding the odds of careless interference with vital physiological actions of -ht. references bismuth-evenzal, y., gonopolsky, y., gurwitz, d., iancu, i., weizman, a. & rehavi, m. . decreased serotonin content and reduced agonist-induced aggregation in platelets of patients chronically medicated with ssri drugs. j affect disord, , - . cooper, j., bloom, f. & roth, r. . serotonin ( -hydroxytryptamine), histamine and adenosine.) the biochemical basis of neuropharmaclogy. oxford university press, new york. doggrell, s. a. . the role of -ht on the cardiovascular and renal systems and the clinical potential of -ht modulation. expert opin investig drugs, , - . gergs, u., baumann, m., bockler, a., buchwalow, i. b., ebelt, h., fabritz, l., hauptmann, s., keller, n., kirchhof, p., klockner, u., ponicke, k., rueckschloss, u., schmitz, w., werner, f. & neumann, j. . cardiac overexpression of the human -ht receptor in mice. am j physiol heart circ physiol, , h - . kaludercic, n., carpi, a., menabo, r., di lisa, f. & paolocci, n. . monoamine oxidases (mao) in the pathogenesis of heart failure and ischemia/reperfusion injury. biochim biophys acta, , - . levy, f. o., qvigstad, e., krobert, k. a., skomedal, t. & osnes, j. b. . effects of serotonin in failing cardiac ventricle: signalling mechanisms and potential therapeutic implications. neuropharmacology, , - . nebigil, c. g., choi, d. s., dierich, a., hickel, p., le meur, m., messaddeq, n., launay, j. m. & maroteaux, l. . serotonin b receptor is required for heart development. proc natl acad sci u s a, , - . page of acta physiologica f o r p e e r r e v ie w nebigil, c. g. & maroteaux, l. . functional consequence of serotonin/ -ht b receptor signaling in heart: role of mitochondria in transition between hypertrophy and heart failure? circulation, , - . ong, s. b. & gustafsson, a. b. . new roles for mitochondria in cell death in the reperfused myocardium. cardiovasc res, , - . pavone, l. m., spina, a., lo muto, r., santoro, d., mastellone, v. & avallone, l. . heart valve cardiomyocytes of mouse embryos express the serotonin transporter sert. biochem biophys res commun, , - . ponicke, k., gergs, u., buchwalow, i. b., hauptmann, s. & neumann, j. . on the presence of serotonin in mammalian cardiomyocytes. mol cell biochem, , - . sadler, t. w. . selective serotonin reuptake inhibitors (ssris) and heart defects: potential mechanisms for the observed associations. reprod toxicol, , - . sauer, w. h., berlin, j. a. & kimmel, s. e. . selective serotonin reuptake inhibitors and myocardial infarction. circulation, , - . sivasubramaniam, s. d., finch, c. c., rodriguez, m. j., mahy, n. & billett, e. e. . a comparative study of the expression of monoamine oxidase-a and -b mrna and protein in non-cns human tissues. cell tissue res, , - . sonobe, t., akiyama, t., du c-k., zhan, d.-y. & shirai, m. . contribution of serotonin uptake and degradation to myocardial interstitial serotonin levels during ischemia-repefusion in rabbits. acta physiol in press. anna bogdanova institute of veterinary physiology, vetsuisse faculty and the zurich center for integrative human physiology, university of zurich, zurich, switzerland e-mail: annab@access.uzh.ch page of acta physiologica /home/www/ftp/data/hep-ph/dir_ / .dvi hyperons, charm and beauty hadrons: conclusion and outlook josé bernabéua adep. de f́ısica teòrica, univ. de valència, dr. moliner , e- , burjassot, valència, spain in this concluding talk, the advances in the flavour problem studies are discussed, following the structure of the presentations in the conference. the subjects touched are organized as follows: baryons, k-physics, charm and beauty production, charm and beauty decays, b-mixing and cp-violation, heavy quarkonium. . introduction. the subjects presented in the conference [ ] have in common their contribution to the un- derstanding of the flavour problem ”from be- low”, i.e., from detailed studies of the structures, regularities and differences among the flavoured hadrons. in this edition, many new interesting re- sults have been presented and my discussion will be necessarily limited in scope. i apologize for the omissions or simplifications in the conclusions given here. the quarks carry (among other properties) the flavour quantum number conserved by strong and electroweak neutral current interactions to lead- ing order. they are organized in three fami- lies which appear as replicas. besides the an- thropic statement that three families is the min- imum number able to build a universe with the prospect of being understood by humans through science, we do not have still an explanation for the mistery of this replication. except for weak charged current interactions, the other fundamen- tal forces are unable to connect the families each other. in the standard model, the ckm mixing matrix gives account of this problem according to the scheme in fig. . the second mistery in the flavour problem is the hierarchy of mixings, with intensities of order λ, λ , λ for the transitions shown in the fig. . in the step from quarks to hadrons, however, the different quark masses pro- vide an essential difference between the structure λ λ b λ u c s figure . ckm mixing matrix scheme. of light hadrons (u, d and s) and that of heavy sys- tems (c, b and t). the plan of this contribution is as follows. in section , we discuss baryons, with some emphasis on hyperons. section is devoted to k-physics, with the highlight of the last two years: ktev and na confirm the . σ na result of direct cp-violation. in section , charm and beauty production, the study of the fragmentation function provides the link between quarks and hadrons. section discusses charm and beauty decays, including semileptonic, purely leptonic, hadronic and rare decays. the prob- lem of b (and d) mixing and cp violation is presented in section , with the novel results of babar at pep-ii and belle at kek b. heavy quarkonium is discussed in section . finally, section gives some outlook. table comparison between the predicted and experi- mental values of the inclusive semileptonic widths of Λc and Λb. brsl(%) model experiment Λc . . ± . Λb . + . − . . baryons. the study of semileptonic decays of heavy baryons has been addressed [ ] in a consistent quark model describing baryons. a single set of parameters is used for the whole spectra and the resulting structure is tested with decays. the investigation of inclusive semileptonic Λb decays can provide information on the ckm matrix el- ements vcb and vub, as well as on the structure of Λb. the approach is that of a potential model with physical values of the couplings. the sum over final hadronic states is treated by means of duality. the predicted value of the inclu- sive semileptonic widths of Λc and Λb are con- fronted to the experiment [ ] in table , where the branching ratios are given. the exclusive/inclusive ratio re of semilep- tonic Λb → Λc decay has been compared with the corresponding ratio for the meson b → d + d∗, with the conclusion [ ] that it should be larger. one needs the slope parameter ρ b of the isgur- wise form factor fb (ω) in Λb → Λc lν fb (ω) = − ρ b (ω − ) + c (ω − ) + · · · ( ) and an upper bound is taken from the spectator quark model limit ρ b ≤ ρ m − ( ) with the experimental value [ ] ρ m = . ± . . from qcd sum rules, . ≤ ρ b ≤ . , and one finds a ratio . ≤ re (baryon) ≤ . to be compared with re (meson) = %. table comparison between the predicted and experi- mental values of the b hadron lifetime ratios. experiment theory τ (b+) τ (bd) . ± . + . ( fb mev ) τ (bs) τ (bd) . ± . ± . τ (b baryon) τ (bd) . ± . . the exclusive process Λb → Λc lνl has been experimentally searched by delphi collabora- tion [ ], with the analysis addressed to measure the slope parameter ρ b of the form factor ( ). with appropiate cuts in pl and p⊥, the invariant masses m(Λc e), m(Λc µ), a candidate is taken as the sign of l opposite to that of Λc. they find ± events and the measure of the slope pa- rameter gives ρ b = . ± . (sta) ± . (syst) ( ) when the absolute event rate is included in the fit. a review on the b hadron lifetimes was pre- sented [ ] by wasserbaech, aleph coll. recent measurements from lep, sld and cdf indicate that we have still a problem with the lifetime of Λb. from the theoretical side, the measurement of the individual lifetimes of b+, bd, bs and Λb yields information about nonspectator mech- anisms. the experimental results for the lifetime ratios are given in table , together with the theo- retical predictions from qcd-based heavy quark expansions. a theoretical study [ ] of the lifetime problem in the light-front quark model suggests that the fermi motion of the b quark inside Λb can pro- duce a reduction of about ± %, accounting for a significant fraction of the discrepancy. the measurement of the ratio of meson life- times has also been considered recently [ ] by sld, with the result τ(b+)/τ(bd) = . ± . , to be compared with the value in table . the hyperon working group of the ktev col- laboration at fermilab has studied [ ] the Ξ beta decay branching ratio Ξ −→ Σ+ + e− + ν̄e ↪→ p + π ( ) with a signal of ± events and a background of ± events. the process is described by the hadronic vertex of fig. with form fac- Σ + e− νe Ξ us s s u u figure . hadronic vertex for Ξ → Σ+ e− ν̄e. tors, vector and axial. the pseudotensor (or weak electricity) form factor cannot be generated in the standard model with quark constituents. the scalar and pseudoscalar form factors give contributions proportional to the electron mass and thus negligible. this argument is not valid for muons. the collaboration aims for the ex- traction of the three forms: vector, magnetic and axial, for Ξ beta decay with events. the present result for the branching ratio is br(e) = ( . ± . ± . ) × − ( ) to be compared to the theoretical su( )f pre- dicted value ( . ± . )× − . in the cm of Σ+, and using the % analyzing power of Σ+ → pπ , the angular correlation between p and e− is the decay asymmetry. for the muonic channel, with a few events, the measured branching ratio is br(µ) = ( . + − + . − ) × − ( ) the ktev hyperon program also includes the measurement [ ] of the hyperon radiative de- cays. the run has emphasized the chan- nel Ξ → Σ + γ, with a preliminary result b.r. = ( . ± . )× − . to obtain the asym- metry parameter, one must study a three stage process: Ξ → Σ + γ , Σ → Λ + γ , Λ → p + π− ( ) the detected particles are p,π from the Λ decay, a γ from the Σ decay and a γ from the Ξ decay. the present value for the asymmetry is α = − . ± . ( ) more data is expected from the run. the theoretical studies of Ξ → Σ γ are based on the quark diagrams in fig. corresponding to the penguin diagrams (s → d fcnc transition) plus the exchange diagram. the last amplitude u s s u u s s u u s s u w s d w γ g s d w γ γ figure . quark diagrams for Ξ → Σ γ. occurs for hyperons containing a u-quark. the radiative Ξ decays, in the modes Ξ → Λ γ and Ξ → Σ γ, have also been considered by the na collaboration [ ]. na , designed to measure �′/�, has two beam lines to generate ks and kl simultaneously and obtains the neutral hyperons from the ks -target. the results from data are, in units of − , br(Ξ → Λγ) = ( . ± . ± . ) br(Ξ → Σ γ) = ( . ± . ± . ) ( ) they can be measured with ∼ % accuracy. in , the high intensity ks run will produce a statistical gain by a factor of at least ∼ . na has also found about events of the semileptonic beta decay of Ξ . the future na programs for ks and hy- peron rare decays have been discussed by fan- techi [ ], in competition with kloe and ktev, respectively. a novelty is the aim to look for di- rect cp violation by means of an asymmetry in the dalitz plot density of the three-body decays k± → π±π+π− and k± → π±π π . sensitivi- ties of the order − are envisaged for the later phase. an exotic role of the hyperons in astrophysics has been presented by miralles [ ]. the pres- ence of hyperons allows a scenario in which a proto-neutron star is formed and emits neutrinos during tens of seconds. after deleptonization, it collapses to a black hole. this mechanism can be invoked to explain the lack of a neutron star rem- nant in the sn a and the detection of neutri- nos from the supernova explosion. . k-physics. the present world average for �′/� has been discussed [ ] by unal, from the na collab- oration. with the results of the last two years, ktev and na have confirmed the original . σ finding by na of direct cp-violation in the k −k̄ system. with indirect cp-violation, i.e., in the ∆s = mixing, established since , the mass eigenstates ks,l are not pure cp eigen- states (k±): ks ≈ k+ + �k− kl ≈ k− + �k+ ( ) where |�| = ( . ± . ) × − . to generate direct cp-violation, i.e., in the de- cay amplitude |a(k → ff̄)| = |a(k̄ → ff̄)|, one needs the interference of two decay ampli- tudes. the final state of two pions has contribu- tions from isospin i = and i = , a and a . the imaginary part of the interference generated by weak cp phases (besides the strong phases) leads to the �′ parameter �′ = i√ im ( a a ) ei(δ −δ ) ( ) the ratio of amplitudes from kl and ks has contributions from � and �′ a(kl → π+π−) a(ks → π+π−) ≡ η+− = � + �′ a(kl → π π ) a(ks → π π ) ≡ η = � − �′ ( ) in order to separate �′ experimentally, one con- siders the ratio of ratios of decay rates r = Γ(kl → π π ) Γ(ks → π+π−) Γ(ks → π π ) Γ(kl → π+π−) = − re ( �′ � ) ( ) to establish direct cp violation, one needs r = . in the standard model, � is generated from the box diagram whereas �′ gets its dominant value from gluonic and electroweak penguin diagrams. the experimental situation is pictured in the figure . ’ r e( / ) x ε - +- . . ε na e ktev na figure . experimental measurements of �′/�. one realizes from the world average value that �′/� = is well established, but the actual value is probably not. as illustrated in figure , the χ is poor. more results from na , ktev and kloe, which uses a different method, will clarify the experimental situation. the establishment of direct cp-violation tells us that a superweak [ ] explanation is ruled out, and that the k-system needs a milliweak model to describe cp violation. in the standard model, this description is understood in terms of the rel- ative magnitudes of the sides of the unitary tri- angle, shown in fig . the cp-asymmetries are cd cs * ~λ |v v | ud us * ~λ |v v | |v v |td ts * ~ λ figure . the (sd) unitarity triangle. thus expected to be of order λ . the calculation of the two isospin amplitudes a , makes use of the ∆s = effective hamil- tonian, which leads to four-quark operators of the current-current form (q , ), qcd penguin (q → ) and electroweak penguin (q → ) dia- grams. in conventional notation, q and q are most important, but their matrix elements have opposite signs. possible cancellations are thus a potential danger in the theoretical calculations. in fact, im a is dominated by q whereas im a is dominated by q . it is well known that, around mev, the π π interaction is very strong in the scalar-isoscalar channel. the role of final state interactions is thus very important [ ] for the a -amplitude. what is a subject of debate [ ] is whether the dis- persive computation has enough reliability. this is a difficult problem, but the omnès resumma- tion of chiral logarithms [ ] gives a % en- hancement. in this case, a and thus q , is the primary problem. this leads to an estimate �′/� = ( ± )× − , compatible with the present experimental value. models of low energy dynamics point towards a connection between the ∆i = / rule and a ”large” �′/�. lattice qcd simulations will tell us whether this suggestion has a firm ground. a review on the final cplear results on cp, t and cpt in the neutral kaon system was pre- sented by zavrtanik [ ]. for the π decay chan- nel, this experiment has observed for the first time a difference in the time dependence of the k and k̄ decay rates. cp violation implies t viola- tion or cpt violation or both. is t-violated? cplear has measured the kabir asymmetry [ ], by comparing k → k̄ versus k̄ → k . the flavour tag at the production time is defined by the charged kaon pp̄ → k−π+k , k+π−k̄ . the strangeness of the neutral kaon at the de- cay time is defined by the lepton charge in the semileptonic decay (∆s = ∆q). the kabir asymmetry is a genuine t-violating observable, which needs both t-violation and ∆Γ = . this method works thus for neutral kaons, due to the difference in ks and kl lifetimes. cplear re- sults are compatible with equal cp and t viola- tions and cpt invariance. . charm and beauty production in the production of heavy hadrons, the frag- mentation function [ ] is the link between the heavy quark and the heavy hadron. it is parametrized by the probability f(z) that a hadron shares a fraction z of the quark momen- tum z = (e + p‖)h (e + p)q ( ) the problem with the variable z is the denomi- nator, which refers to the quark before fragmen- tation, so that z is not accessible on a event-by- event basis. new variables which are experimen- tally accessible are defined as the hadron energy with respect to the beam energy xe ≡ eh ebeam ( ) there are recent results on 〈xb〉 for the b meson from aleph, delphi, opal and from sld, with values for the leading b energy ranging from . → . . the methodology follows different strategies, and still one has to understand the consistency of the different analyses. at sld, the polarization of the electron beam is used to tag b-quarks with % efficiency [ ]. the re- construction of the secondary vertex by exploit- ing the kinematics leads to a measurement of the mean energy of weakly-decaying b hadrons, with a value 〈xb〉 = . ± . . the selex experiment [ ] emphasizes the understanding of charm production in the for- ward hemisphere. qcd factorization predicts that heavy quarks hadronize through jet fragmen- tation functions independently of the initial state. the experimental data show that the produced charm (anticharm) quark combines with a pro- jectile valence quark. Λ+c is a leading particle when produced by the beams π−, p, Σ−. the Λc hadroproduction has a hard xf distribution. there is a strong production asymmetry in favour of Λ+c over Λ − c for baryon beams. it is less strong for a π− beam. . charm and beauty decays the semileptonic b-decay studies have the dou- ble objective of the understanding of the dynam- ics of heavy quark decays plus the extraction of the ckm coupling constants vcb, vub. the inclu- sive br(b)sl has been discussed by margoni [ ], with different strategies of b-lifetime and lepton tags exploited at lep. for the first time, del- phi has explicitly separated by direct measure- ment br(b → c̄ → l−). at present the analyses to extract vcb are mainly limited by theory (b → l, b → c → l decay models). the most precise de- termination in the ope approach to analyze the lep data gives |vcb|incllep = ( . ± . (exp.) ± . (theo) ) × − ( ) the alternative to the inclusive decay is the study of the exclusive b → d∗ lν decay as a function of the d∗ recoil dΓ dω = k(ω) f (ω) |vcb| ( ) where k(ω) is a phase space factor and f(ω) is the isgur-wise form factor, for which the heavy- quark-effective-theory value for no recoil ω = is estimated. the problem is that, due to k(ω), the decay rate vanishes at ω = . the procedure is thus the measurement of dΓ dω to fit it and extrap- olate to ω = to obtain f( ) |vcb|. these mea- surements at lep have been presented by terem [ ]. there is a problem with b → d∗∗ lν, fol- lowed by d∗∗ → d∗+ x, which is an important systematic effect. aleph and delphi fit to d∗ and d∗∗ contributions gives br(b− → d∗∗ ( → d∗+π− ) lν) = ( . ± . ± . ) % ( ) the lep average for the exclusive analysis gives |f( )vcb| = ( . ± . ) × − , with higher ex- perimental error than ( ) due to small samples, but much cleaner theoretical approach. the determinations of vub can come from either the exclusive b → π,ρlν decays, where the main limitation is statistics or the inclusive lepton end- point analysis, above the process b → clν. this method, limited by theoretical uncertainties, ex- tracts [ ] a measurement of the branching ratio for inclusive charmless semi-leptonic b decays br(b → xu lν) = ( . ± . ) × − ( ) from aleph, delphi and l at lep. the lep average for the vub value derived using hqet is |vub| = ( . + . − . ) × − ( ) aleph takes million e+ e− → z → q q̄ events to measure [ ] the branching fractions for ds → τ ν (τ → eνν̄ or τ → µν ν̄) and ds → µν. due to chirality suppression in the pseudoscalar decay of fig. the ds → eν decay is not acces- ν d sf w l figure . pseudoscalar decay ds → l ν̄. sible. the two leptonic τ decay channels, which give consistent signals, measure br(ds → τ ν) = ( . ± . ± . )% ( ) whereas the ds → µν analysis gives br(ds → µν) = ( . ± . ± . )% ( ) the two results ( ) and ( ) are consistent with the chirality suppression and phase space factors m l ( − m l m ds ) and provide a proof of leptonic universality in charged current decays. combinig them, one gets for the decay constant fds = ( ± ± ) mev ( ) which can be used to check the validity of its pre- diction by different theoretical models. lattice qcd predicts a value + − mev. hadronic decays b∗ → b π, d∗ → d π allow [ ] the extraction of the physical coupling 〈b (p) π+(q)|b∗+(p′)〉 = gb∗bπ(q ) �µ qµ ( ) gb = lim q →m π gb∗bπ(q ) and analogously for the d∗ d transition. these b* b π figure . vertex b∗-b-π. form factors have been obtained theoretically from qcd sum rules [ ]. they cannot be de- scribed by a monopole function. two different methods give consistent results and one gets for the coupling constants gd = . ± . , gb = . ± . ( ) the excited states of d, ds, b and bs mesons have been studied [ ] in the framework of the relativistic heavy chiral quark model, with the de- termination of spectrum and wavefunctions. the /mh-effects are relevant for the calculation of the decay amplitudes of b∗∗ → b + η, π and k. de- cay channels of b∗∗ are useful for flavour tagging in particle detectors. the decays d+, d+s → π−π+π+ were studied experimentally by the e collaboration [ ], at fermilab fixed target programme. the exper- iment runs for gev π−-nucleon interactions and the signals yield ( ± ) d+ events and ( ± ) d+s events. besides the branching ra- tios, a detailed analysis of the dalitz plots has been perfomed. the invariant mass m π+π− dis- tribution for d+s → π−π+π+ is completely dom- inated by f ( ) and f ( ), as shown in the fig. , with a negligible non-resonant contribu- tion. the behaviour of the m π+π− distribution +π− m (gev )π figure . m π+π− distribution for d + s → π−π+π+. for d+ → π−π+π+ is however completely dif- ferent, with a dominant non-resonant contribu- tion shown in fig. . what is the origin of the low mass peak? one is led naturally to the σ- meson, the scalar-isoscalar predicted by nambu and jona-lasinio in a linear realization of the chi- ral lagrangian. experimentally, it has suffered all kinds of up’s and down’s in the review of particle properties along the years. the inclusion of the σ in the fit leads to an spectacular improvement and to the determination of its mass ( ± ) mev and width ( ± ) mev. the light σ( ), in spite of its broadness, is up again ! +π−m (gev ) π figure . m π+π− distribution for d + → π−π+π+. rare decays are a good probe for searching new physics. the branching ratios for the inclusive b → xs l+ l− and exclusive b → k(∗) l+ l− de- cays are smaller in the standard model than the experimental bounds, so that there is room for contributions from models beyond the standard theory. in particular, there is a very interest- ing property [ ] in b → k∗ l+ l−: the zero of the forward-backward asymmetry provides a dis- crimination between the standard model and su- persymmetry. the very rare ∆s = process b → ssd̄ is de- scribed in the standard model by the box diagram of fig. . with a branching ratio of the order b w w s d s figure . standard model box diagram for b → ssd̄. − . whereas the mssm squark-gaugino box q ~q g~ g~ ~ b s d s figure . mssm squark-gaugino box diagram for b → ssd̄. diagram in fig. can increase [ ] the theoret- ical branching ratio to levels of − , the mssm with r parity violating couplings induced by the sneutrino, see fig. , is not restricted. on the ∼ν db s s figure . mssm sneutrino-mediated diagram for b → ssd̄. contrary, data from lep , around the z reso- nance, allow the search for b− → k− k− π+ [ ]. the upper limit of ∼ − for the branching ratio leads to new limits on the contribution of r parity violating couplings in this process. . b(d) mixing and cp-violation for charm mesons, the two parameters of mix- ing x = ∆m Γ , y = ∆Γ Γ ( ) are small. the experimental methods to see x or y are either by mixing, with wrong sign final lepton, or comparing the lifetime of cp eigenstates. the last method takes into account the expectation that cp-violation for the charm sector is small. focus(e ) selects [ ] the two channels d → k+ k− (cp +) d → k− π+ (cp + : cp − = : ) ( ) and the direct comparison of cp final state life- times finds ycp as ycp = τ(d → k π) τ(d → k k) − ( ) the experimental result is ( . ± . ± . )%. the standard model predicts that direct cp vi- olation in d decay rates is the largest in singly cabbibo-suppressed decays d+ → k− k+ π+, d → k− k+, π− π+. the cp asymmetry re- sults [ ] show no evidence for cp violation at the level of few percent. in the b sector, the problems of bd and bs mix- ing allow the extraction of vtd and vtd/vts matrix elements of the ckm matrix. in the time inte- grated approach, the bd-mixing leads to a world average ∆md = . ± . ps− , but the bs- mixing has no sensitivity to ∆ms. the method used [ , ] needs a time dependent experimen- tal approach. the time dependent mixing gener- ates a periodic signal. the amplitude fit method measures the oscillation amplitude a at fixed fre- quency ∆ms. one expects a = on a frequency equal to the true ∆ms, whereas a = for a wrong frequency. the world combination leads to the conclusion that bs oscillations have not yet been resolved, with a lower limit ∆ms > . ps− . the standard model preferred value is close to the present reach. in the aleph data, there is a hint of a signal around ps− . with expected sensitivities like ∼ ps− , one can envisage very interesting results in the near future. the measurement of ∆Γs has been addressed with many methods [ ]. an appreciable value would allow to see cp violation in untagged bs, contrary to bd in which ∆Γd ≈ . with the constraint Γs = Γd = Γ, the present combined experimental value by the lep working group is ∆Γs Γ = . + . − . . this is still an insufficient sensitivity to claim an observed width difference. the standard model preferred value is . ± . [ ], using lattice hqet and extrapolated lat- tice qcd. one of the highlights of the conference is the presentation that the two b-factories and the cor- responding detectors, babar at pep-ii [ , ] and belle at kek b [ , ], are working very well. the pep-ii gev e− against . gev e+ collider expects a luminosity of about × cm− s− around summer , whereas the kek b gev e− against . gev e+ collider had a luminosity about × cm− s− just be- fore the conference in june . some of the many physics results which are being analyzed by the two collaborations have been presented, in particular, the lifetimes τ(b), τ(c) and τ(τ), the mixing ∆md, the inclusive b → j/ψ x de- cay, the charmless b → ρπ decay, the dominant ”cabibbo allowed” br(b → d∗ π) and br(b → d∗+s d ∗−), or the rare b → k∗ γ, b → k∗ l+ l− decays. the main objective of the b-factories is to es- tablish cp-violation outside the k-system and see whether its description obeys to the ckm mix- ing matrix in the standard model. for the (bd) unitarity triangle, the three sides mediated by u, c, t quarks are of similar size of order λ . when the cp conserving direction is taken as a refer- ence and the associated side is normalized to one, the (bd) unitarity triangle is shown in fig. . b-physics has the power to find observables able cp (ρ.η) (t)(u) (c) cp γ α β figure . (bd) unitarity triangle. to overconstrain the parameters of this triangle. the separate measurement of the weak cp phases α, β, γ is possible. the value of sin( β) is acces- sible from the cp asymmetry in b → j/ψ ks generated from the interplay of mixing and de- cay. this method needs a flavour tag, as given by the lepton channel or others. suppose the decay of Υ( s) into an entangled state of two b’s: Υ( s) → b b   • b → d− e+ ν (tag) • b̄ → j/ψ ks ∆z ( ) after a time ∆t (or length ∆z) from the tag, the cp eigenstate b− is observed: the comparison of b → b− versus b̄ → b− measures cp viola- tion. bañuls [ ] has discussed the way to use these decays to look for t and cpt violation. starting from the transition b → b−, one has b → b− b− → b b− → b̄ ( ) these transformed transitions need a cp tag. in order to project first on b−, the b of the other side has to be identified as b+, a difficult prob- lem. there is, however, an equivalent transition for hermitian hamiltonians. in the limit ∆Γd = (an excellent approximation for bd), the transi- tion b− → b is equivalent to b+ → b̄ , which is obtained from the original b → b− by a tem- poral exchange ∆z → −∆z of the two decay channels: leptonic and j/ψks. although the temporal and t-odd asymmetries are conceptu- ally different, they become equivalent in the limit ∆Γd = and the temporal asymmetry is a t-odd observable. the problem of b-physics and cp-violation is a source of inspiration and dedication in the hadronic machines too. at the conference, the prospects of cdf-ii [ ], btev [ ], ckm [ ], and run ii [ ] at fermilab, as well as hera b [ ] at desy and atlas [ ], cms [ ] and lhcb [ ] at lhc [ ] were given. a brilliant sce- nario appears at the near future. contrary to the b-factory preparation, the b-production mecha- nism is thought to be here incoherent from the individual b quark, with no entanglement. one can proceed then to flavour tags, but there is no possibility of cp tags as discussed above. it is worth to emphasize that, inside the stan- dard model, the cp phases can be also extracted from cp conserving observables in exclusive b- decays. for example, cos α is measured in the rare b → ργ decay [ , ]. the evidence for α = in the (bd) unitary triangle is here cos α = in these observables, contrary to sin α = (yes-no experiment) in the cp-odd asymmetries. the chapter of sm physics was also addressed by narain [ ], with an excellent review of top quark physics at the tevatron (run i and run ii) and the lhc as a top factory. . heavy quarkonium quarkonia are special hadrons, for which a de- scription in terms of factorization between the hard and soft scales is believed to be valid. for the case of Υ, confinement effects are small and basic perturbative qcd calculations on some ob- servables [ ] can be envisaged. these observ- ables refer to structure and decays. the only flavour dependent parameter is the b quark mass m at the scale of the bound state. the running of the b quark mass has been established [ ]. with the velocity v ∼ α for coulomb systems, one has a multiscale problem with m, p ∼ mv, e ∼ mv . the separation of scales is made by means of an effective field theory [ ]. there is a j/ψ and ψ′ surplus in direct pro- duction at the tevatron. an interesting produc- tion mechanism which has been suggested is the colour-octet component in nrqcd. chao [ ] has discussed a test of this mechanism, which in- corporates the colour-octet gluon fragmentation shown in fig. based on the polarization of charmonium at the tevatron. in the nrqcd factorization approach, an explicit calculation of the production cross section [ ] shows that the colour-octet contributions can describe tevatron data. the experimental j/ψ polarization at high pt is, however, in disagreement with the calcu- lation for direct j/ψ production plus the feed- down from intermediate χc and ψ′. more tests are needed to understand this problem. figure . color-octet gluon fragmentation. the inelastic j/ψ production in dis ( < q < gev ) at hera shows [ ] that the colour- singlet contribution is below data, but the shape is in reasonable agreement. when the colour- octet contribution, as suggested by the tevatron data, is included, the theoretical magnitude is above data and the shapes disagree. clearly one has to conclude that the problem of the produc- tion mechanism is not understood yet. . outlook the conference was a great event. many ex- perimental results and theoretical ideas were pre- sented and discussed. the understanding of the flavour problem is one of the main pending ques- tions in fundamental physics. in the quark sector, this study involves strange, charm and beauty hadrons, and so the control of the interplay be- tween electroweak and strong interactions. it is gratifying for this field that all major facilities in particle physics around the world have a strong programme in it. as a consequence, we can ex- pect important breakthroughs in the next two years and to have a fruitful rendez-vous at van- couver . . acknowledgements i would like to thank the organizers of the conference for the appropriate environment and to vicent giménez for a critical reading of the manuscript. this work was supported by cicyt, under grant aen - . references . transparencies of most conference talks are available at http://ific.uv.es/conf /con- tributions.html. . c.s. kalman, these proceedings. . review of particle physics, c. caso et al. eur. phys. j. 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( ) . . a. pich, these proceedings and hep- ph/ . . l. silvestrini, these proceedings and hep- ph/ . . d. zavrtanik, these proceedings. . p.k. kabir, the cp puzzle, academic press ( ) . t. bocali, these proceedings. . m. iori, these proceedings and hep- ex/ . . m. margoni, these proceedings. . s. terem, these proceedings. . m. battaglia, these proceedings and hep- ex/ . . h. he, these proceedings. . p. singer and d. guetta, these proceedings and hep-ph/ . . m. nielsen, these proceedings. . m. di pierro and e. eichten, these proceed- ings and hep-ph/ . . i. bediaga, these proceedings and hep- ex/ . . c.-s. huang, these proceedings and hep- ph/ . . s. fajfar, these proceedings. . y. rozen, these proceedings. . d. y. kim, these proceedings. . g. boix, these proceedings. . j. reyes and v. giménez, these proceedings; hep-lat/ and hep-lat/ . d. becirevic et al., hep-ph/ . . p.c. bloom, these proceedings. . b. meadows, these proceedings. . b.a. shwartz, these proceedings. . b.g. cheon, these proceedings. . m.c. bañuls, these proceedings and hep- ph/ . . a. ruiz, these proceedings. . y. kubota, these proceedings. . c. milstene, these proceedings and hep- ex/ (with the ckm collaboration). . r. jesik, these proceedings. . k. ehret, these proceedings. . m. smizanska, these proceedings. . p. arce, these proceedings. . j. libby, these proceedings. . n. ellis, these proceedings. . b. grinstein, these proceedings. . l.t. handoko, these proceedings and hep- ph/ . . m. narain, these proceedings. . f.j. yndurain, these proceedings. . m. j. costa, j. fuster, these proceedings. . a. manohar, these proceedings. a. pineda, these proceedings and hep- ph/ . . k.t. chao, these proceedings. . m. krämer, these proceedings and hep- ph/ . . a. polini, these proceedings. λ λ b λ u c s b w w s d s q ~q g~ g~ ~ b s d s ∼ν db s s cp (ρ.η) (t)(u) (c) cp γ α β Σ + e− νe Ξ us s s u u u s s u u s s u u s s u w s d w γ g s d w γ γ ’ r e( / ) x ε - +- . . ε na e ktev na cd cs * ~λ |v v | ud us * ~λ |v v | |v v |td ts * ~ λ ν d sf w l b* b π +π− m (gev )π +π−m (gev ) π british medical journal volume - december medicine and pictures beauty and the dole richard smith many of britain's hospitals are ugly and depressing, and more than three million people are unemployed. wouldn't it make sense if some of the unemployed helped beautify our hospitals? it would, and a walk down the several hundred yards of corridor of bethnal green hospital shows that it is already happening. the corridor is lined with paintings by unemployed people. the first one you see shows a boy fishing in one ofthe east end's hidden canals. it must be five feet by four, and a casual observer could be excused for thinking it a particularly vibrant and large colour photograph. in fact it is a painting, which might be described as ultrarealist, painted by an unemployed girl who had never painted before. if you were one of the old people who are now the inhabitants of the hospital, you might be reminded of when you were a child and fished in the canal. or perhaps you would think of your grandson, fishing there at that moment. as you walked on down the corridor you would be reminded ofmuch more, particularly if you knew the east end well. tubby isaacs is selling shellfish; bells are being cast in the whitechapel foundry; people are snoozing on deckchairs in the park; small boys are collecting money for guy fawkes night, while others are painting themselves as clowns; an asian man and his son are looking out of their shop window, just a little frightened; the cat meat man is coming; and that cheerful woman (what's her name again?) is still selling cigarettes from her tiny kiosk. similar pictures can be seen in the outpatients department at the london hospital. the biggest one shows the market across the road from the hospital in full swing, and patients waiting to see the doctor can study the characters and often recognise friends. one of the greengrocers recently died, and in his obituary the hackney gazette said that he had been "immortalised" in the painting at the london hospital. the or so pictures at bethnal green are large, and they might-until you look closely-all have been painted by the same person. but they weren't, although most were painted by a similar technique, one borrowed from venetian painters like canaletto. o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j (c lin r e s e d ): first p u b lish e d a s . /b m j. . . o n d e ce m b e r . d o w n lo a d e d fro m http://www.bmj.com/ british medical journal volume - december the venetians used lenses and mirrors to project canal scenes on to their canvases, whereas the unemployed of the east end have used slides and projectors. in a painstaking process that takes up to six months they have painted the projections and created startlingly evocative scenes. the result is that what might have been a depressing and seedy corridor distinguished only by the smell of boiled fish is as well worth a visit as the hayward gallery. most of these paintings are now several years old, and the programme that gave long term unemployed people the confidence to paint so well has moved on. now people are working on projects as varied as creating gardens for the disabled, making stained glass windows for the hospitals and residential homes of towerhamlets and hackney, producinghealth promotionmaterial, and building strong wooden chairs for disabled people. in addition, the participants in the project are making sure that the patients in bethnal green hospital can share in their work, and most recently some of the participants have begun to work directly with the old people, helping them to make their own pictures. the project was begun in and sponsored by shape, an organisation that encourages art in hospitals, prisons, everywhere. four unemployed painters spent six months in the london hospital and six months in hackney hospital. one of those unemployed painters was michele bacciottini, who is now manager of the whole project. after the first year michele approached the london hospital to "sponsor" the project and the manpower services commission to put up the money. the london hospital's "sponsor- ship" cost it nothing: it simply had to find a corner for the four painters and be willing for them to work on hospital projects. they began by painting a mural ofwinnie the pooh in one ofthe children's units at the london hospital. they were criticised by some of the staff for choosing such a middle class subject in such a working class area, but the staff were lagging behind their charges. although the parents of the east end might not have encountered pooh and his pals, their children had, and they delighted in the pictures ofeeyore, baby roo, kanga, and piglet against a cotswold background. this picture proved to be important in getting future funding for the project because the danish minister of health came to visit the unit together with some "bigwigs" from the manpower services commission. he turned out to be a fan of pooh as well as of the mural, and the "bigwigs" enjoyed the reflected glory. this has been useful becauseeachyearmichelemustapply again to thecommission for money, and it is becoming increasingly oriented towards industrial projects. the commission has always stumped up so far, but one year a panic ran through the commission because of criticism of some of the painting projects that it supported. a decision was taken to stop supporting all painting projects, which could have meant the end of the east end project. but the people ofbethnal green were determined that this should not happen. a petition was organised, and local union leaders led the protest. one wrote to sir hugh casson, then president of the royal academy, and asked him to come and give his blessing. he was abroad, but the secretary of the academy came and was much impressed by what he saw. pressure from the academy helped keep the project going. the local union leaders were most helpful on that occasion, but the unions have been suspicious of msc schemes. isn't this slave labour? aren't these second class jobs? aren't the participants doing work that should rightly be done by full time workers, union men? michele understands their point of view but is confident that this o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j (c lin r e s e d ): first p u b lish e d a s . /b m j. . . o n d e ce m b e r . d o w n lo a d e d fro m http://www.bmj.com/ brmsh medical journal volume - december ... isn't the case. the participants in his project are artists, and there were no artists in the hospitals of the east end before they came. nobody made gardens or painted pictures to brighten the walls. he is also sure that the work that the participants do with the patients is something new and different. something extra is being achieved, nobody is being pushed out. but the real beauty of this project is that it is not just the patients and the hospitals that benefit-the participants benefit as well. all of them are long term unemployed people, and many have spent years unemployed in the east end-"a real tough experience," observes michele. many have had their confidence destroyed, and some have had serious problems-have attempted suicide, been for psychiatric treatment, or been in prison. they come to the project for a year, and michele sees dramatic changes in their attitudes and confidence. these come partly through mastering skills, partly through working in teams, and partly through working with the patients. what can be hard, however, is leaving after the year is up. but % do go on to get jobs-many ofthem as care assistants or in art related jobs-which is a better rate than for many msc projects. whether the participants or the patients benefit most is anybody's guess, but i had a chance to see what pleasure was given to some of the patients. one of the participants in the project had been given space to exhibit his own work at the half moon theatre in mile end. he had given over his space to the patients, and i went to see the exhibition. the old people that i spoke to were terribly chuffed that their work was being exhibited. most had never painted in their lives before and didn't think that they had it in them to create anything that people would want to hang on a wall. as the daughter of one woman said: "i didn't fink she could do nuffin with them 'ands, and yet the painting's wonderful and it's on the wall. it's made 'er really 'appy." the greatest success of the whole project seems to have been to help people to do things that they never thought they could do. dr richard smith is assistant editor, bmj. o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j (c lin r e s e d ): first p u b lish e d a s . /b m j. . . o n d e ce m b e r . d o w n lo a d e d fro m http://www.bmj.com/ british medical journal volume i i p. .. hi_ tic-- - december -&i'.'..-e o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j (c lin r e s e d ): first p u b lish e d a s . /b m j. . . o n d e ce m b e r . d o w n lo a d e d fro m http://www.bmj.com/ production of excited beauty states in z decays european organisation for nuclear research cern-ppe/ - july production of excited beauty states in z decays the aleph collaboration abstract a data sample of about . million hadronic z decays collected by the aleph experiment at lep in the years through , is used to make an inclusive selection of b hadron events. in this event sample � � b� mesons in the decay b� ! b and � � b�� mesons decaying into a b meson and a charged pion are reconstructed. for the well established b� meson the following quantities are obtained: �m = mb� � mb = ( : � : � : ) mev=c and nb�=(nb +nb�) = ( : � : � : )%. the angular distribution of the photons in the b� rest frame is used to measure the relative contribution of longitudinal b� polarization states to be �l=(�l + �t) = ( � � )%. resonance structure in the m(b�) � m(b) mass di�erence is observed at ( � � ) mev=c . its shape and position is in agreement with the expectation for b��u;d states decaying into b (�) u;d� �. the signal is therefore interpreted as arising from them. the relative production rate is determined to be br(z ! b ! b��u;d) br(z ! b ! bu;d) = [ : � : (stat) � : (syst) + : � : (model)]%: where the third error re ects the uncertainty due to di�erent production and decay models for the broad b��u;d states. (submitted to zeitschrift f�ur physik c) the aleph collaboration d. buskulic, d. casper, i. de bonis, d. decamp, p. ghez, c. goy, j.-p. lees, a. lucotte, m.-n. minard, p. odier, b. pietrzyk laboratoire de physique des particules (lapp), in p -cnrs, annecy-le-vieux cedex, france f. ariztizabal, m. chmeissani, j.m. crespo, i. efthymiopoulos, e. fernandez, m. fernandez-bosman, v. gaitan, ll. garrido, m. martinez, s. orteu, a. pacheco, c. padilla, f. palla, a. pascual, j.a. perlas, f. sanchez, f. teubert institut de fisica d'altes energies, universitat autonoma de barcelona, bellaterra (barcelona), spain a. colaleo, d. creanza, m. de palma, a. farilla, g. gelao, m. girone, g. iaselli, g. maggi, m. maggi, n. marinelli, s. natali, s. nuzzo, a. ranieri, g. raso, f. romano, f. ruggieri, g. selvaggi, l. silvestris, p. tempesta, g. zito dipartimento di fisica, infn sezione di bari, bari, italy x. huang, j. lin, q. ouyang, t. wang, y. xie, r. xu, s. xue, j. zhang, l. zhang, w. zhao institute of high-energy physics, academia sinica, beijing, the people's republic of china g. bonvicini, m. cattaneo, p. comas, p. coyle, h. drevermann, a. engelhardt, r.w. forty, m. frank, r. hagelberg, j. harvey, r. jacobsen, p. janot, b. jost, j. knobloch, i. lehraus, c. markou, e.b. martin, p. mato, h. meinhard, a. minten, r. miquel, t. oest, p. palazzi, j.r. pater, j.-f. pusztaszeri, f. ranjard, p. rensing, l. rolandi, d. schlatter, m. schmelling, o. schneider, w. tejessy, i.r. tomalin, a. venturi, h. wachsmuth, w. wiedenmann, t. wildish, w. witzeling, j. wotschack european laboratory for particle physics (cern), geneva , switzerland z. ajaltouni, m. bardadin-otwinowska, a. barres, c. boyer, a. falvard, p. gay, c. guicheney, p. henrard, j. jousset, b. michel, s. monteil, j-c. montret, d. pallin, p. perret, f. podlyski, j. proriol, j.-m. rossignol, f. saadi laboratoire de physique corpusculaire, universit�e blaise pascal, in p -cnrs, clermont-ferrand, aubi�ere, france t. fearnley, j.b. hansen, j.d. hansen, j.r. hansen, p.h. hansen, b.s. nilsson niels bohr institute, copenhagen, denmark a. kyriakis, e. simopoulou, i. siotis, a. vayaki, k. zachariadou nuclear research center demokritos (nrcd), athens, greece a. blondel, g. bonneaud, j.c. brient, p. bourdon, l. passalacqua, a. roug�e, m. rumpf, r. tanaka, a. valassi, m. verderi, h. videau laboratoire de physique nucl�eaire et des hautes energies, ecole polytechnique, in p -cnrs, palaiseau cedex, france d.j. candlin, m.i. parsons department of physics, university of edinburgh, edinburgh eh jz, united kingdom e. focardi, g. parrini dipartimento di fisica, universit�a di firenze, infn sezione di firenze, firenze, italy m. corden, m. del�no, c. georgiopoulos, d.e. ja�e supercomputer computations research institute, florida state university, tallahassee, fl - , usa ; a. antonelli, g. bencivenni, g. bologna, f. bossi, p. campana, g. capon, v. chiarella, g. felici, p. laurelli, g. mannocchi, f. murtas, g.p. murtas, m. pepe-altarelli laboratori nazionali dell'infn (lnf-infn), frascati, italy s.j. dorris, a.w. halley, i. ten have, i.g. knowles, j.g. lynch, w.t. morton, v. o'shea, c. raine, p. reeves, j.m. scarr, k. smith, m.g. smith, a.s. thompson, f. thomson, s. thorn, r.m. turnbull department of physics and astronomy, university of glasgow, glasgow g qq,united kingdom u. becker, o. braun, c. geweniger, g. graefe, p. hanke, v. hepp, e.e. kluge, a. putzer, b. rensch, m. schmidt, j. sommer, h. stenzel, k. tittel, s. werner, m. wunsch institut f�ur hochenergiephysik, universit�at heidelberg, heidelberg, fed. rep. of germany r. beuselinck, d.m. binnie, w. cameron, d.j. colling, p.j. dornan, n. konstantinidis, l. moneta, a. moutoussi, j. nash, g. san martin, j.k. sedgbeer, a.m. stacey department of physics, imperial college, london sw bz, united kingdom g. dissertori, p. girtler, e. kneringer, d. kuhn, g. rudolph institut f�ur experimentalphysik, universit�at innsbruck, innsbruck, austria c.k. bowdery, t.j. brodbeck, p. colrain, g. crawford, a.j. finch, f. foster, g. hughes, t. sloan, e.p. whelan, m.i. williams department of physics, university of lancaster, lancaster la yb, united kingdom a. galla, a.m. greene, k. kleinknecht, g. quast, j. raab, b. renk, h.-g. sander, r. wanke, c. zeitnitz institut f�ur physik, universit�at mainz, mainz, fed. rep. of germany j.j. aubert, a.m. bencheikh, c. benchouk, a. bonissent, g. bujosa, d. calvet, j. carr, c. diaconu, f. etienne, m. thulasidas, d. nicod, p. payre, d. rousseau, m. talby centre de physique des particules, facult�e des sciences de luminy, in p -cnrs, marseille, france i. abt, r. assmann, c. bauer, w. blum, d. brown, h. dietl, f. dydak, g. ganis, c. gotzhein, k. jakobs, h. kroha, g. l�utjens, g. lutz, w. m�anner, h.-g. moser, r. richter, a. rosado-schlosser, s. schael, r. settles, h. seywerd, u. stierlin, r. st. denis, g. wolf max-planck-institut f�ur physik, werner-heisenberg-institut, m�unchen, fed. rep. of germany r. alemany, j. boucrot, o. callot, a. cordier, f. courault, m. davier, l. du ot, j.-f. grivaz, ph. heusse, m. jacquet, d.w. kim, f. le diberder, j. lefran�cois, a.-m. lutz, g. musolino, i. nikolic, h.j. park, i.c. park, m.-h. schune, s. simion, j.-j. veillet, i. videau laboratoire de l'acc�el�erateur lin�eaire, universit�e de paris-sud, in p -cnrs, orsay cedex, france d. abbaneo, p. azzurri, g. bagliesi, g. batignani, s. bettarini, c. bozzi, g. calderini, m. carpinelli, m.a. ciocci, v. ciulli, r. dell'orso, r. fantechi, i. ferrante, l. fo�a, f. forti, a. giassi, m.a. giorgi, a. gregorio, f. ligabue, a. lusiani, p.s. marrocchesi, a. messineo, g. rizzo, g. sanguinetti, a. sciab�a, p. spagnolo, j. steinberger, r. tenchini, g. tonelli, g. triggiani, c. vannini, p.g. verdini, j. walsh dipartimento di fisica dell'universit�a, infn sezione di pisa, e scuola normale superiore, pisa, italy a.p. betteridge, g.a. blair, l.m. bryant, f. cerutti, y. gao, m.g. green, d.l. johnson, t. medcalf, ll.m. mir, p. perrodo, j.a. strong department of physics, royal holloway & bedford new college, university of london, surrey tw oex, united kingdom v. bertin, d.r. botterill, r.w. cli�t, t.r. edgecock, s. haywood, m. edwards, p. maley, p.r. norton, j.c. thompson particle physics dept., rutherford appleton laboratory, chilton, didcot, oxon ox oqx, united kingdom b. bloch-devaux, p. colas, h. duarte, s. emery, w. kozanecki, e. lan�con, m.c. lemaire, e. locci, b. marx, p. perez, j. rander, j.-f. renardy, a. rosowsky, a. roussarie, j.-p. schuller, j. schwindling, d. si mohand, a. trabelsi, b. vallage cea, dapnia/service de physique des particules, ce-saclay, gif-sur-yvette cedex, france r.p. johnson, h.y. kim, a.m. litke, m.a. mcneil, g. taylor institute for particle physics, university of california at santa cruz, santa cruz, ca , usa a. beddall, c.n. booth, r. boswell, s. cartwright, f. combley, i. dawson, a. koksal, m. letho, w.m. newton, c. rankin, l.f. thompson department of physics, university of she�eld, she�eld s rh, united kingdom a. b�ohrer, s. brandt, g. cowan, e. feigl, c. grupen, g. lutters, j. minguet-rodriguez, f. rivera, p. saraiva, l. smolik, f. stephan, p. van gemmeren fachbereich physik, universit�at siegen, siegen, fed. rep. of germany m. apollonio, l. bosisio, r. della marina, g. giannini, b. gobbo, f. ragusa dipartimento di fisica, universit�a di trieste e infn sezione di trieste, trieste, italy j. rothberg, s. wasserbaech experimental elementary particle physics, university of washington, wa seattle, u.s.a. s.r. armstrong, l. bellantoni, p. elmer, z. feng, d.p.s. ferguson, y.s. gao, s. gonz�alez, j. grahl, j.l. harton, o.j. hayes, h. hu, p.a. mcnamara iii, j.m. nachtman, w. orejudos, y.b. pan, y. saadi, m. schmitt, i.j. scott, v. sharma, j.d. turk, a.m. walsh, sau lan wu, x. wu, j.m. yamartino, m. zheng, g. zobernig department of physics, university of wisconsin, madison, wi , usa now at cern, geneva , switzerland. deceased. now at dipartimento di fisica, universit�a di lecce, lecce, italy. also istituto di fisica generale, universit�a di torino, torino, italy. also istituto di cosmo-geo�sica del c.n.r., torino, italy. now at tsm business school, enschede, the netherlands. supported by cicyt, spain. supported by the national science foundation of china. supported by the danish natural science research council. supported by the uk particle physics and astronomy research council. supported by the us department of energy, grant de-fg -er . on leave from universitat autonoma de barcelona, barcelona, spain. supported by the us department of energy, contract de-fg - er . supported by the us department of energy, contract de-fc - er . permanent address: universitat de barcelona, barcelona, spain. supported by the bundesministerium f�ur forschung und technologie, fed. rep. of germany. supported by the direction des sciences de la mati�ere, c.e.a. supported by fonds zur f�orderung der wissenschaftlichen forschung, austria. permanent address: kangnung national university, kangnung, korea. now at dipartimento di fisica, universit�a di milano, milano, italy. also at cern, geneva , switzerland. supported by the us department of energy, grant de-fg - er . now at university of athens, - athens, greece. now at lawrence berkeley laboratory, berkeley, ca , usa. partially supported by colciencias, colombia. also at istituto di matematica e fisica, universit�a di sassari, sassari, italy. now at schuster laboratory, university of manchester, manchester m pl, uk. now at colorado state university, fort collins, co , usa. now at university of california at san diego, la jolla, ca , usa. now at fermi national accelerator laboratory, batavia, il , usa. supported by the commission of the european communities, contract erbchbict . introduction the low lying b( s) states, b and b�, are well established [ ]. from spin counting the relative production rate of b� mesons is expected to be nb�=(nb + nb�) = : . the analogous quantity measured in the charm sector is : � : [ ] in contradiction to the expectation. phase space corrections due to the di�erent masses of the excited- and ground states and the decay modes of the tensor meson states are possible explanations for the observed value. measurements of the b� and b�� production rates and of the b�� branching ratios to b� and b�� are needed in order to test the prediction of . in the beauty sector. the fraction of b quarks forming a b�� state is also of great interest since their expected decay modes into b(�)�� can be used to identify the avour of the b quark at the production time. a method based on this idea has been proposed to measure cp-violation in the decay of the neutral b meson [ ]. due to this proposal much e�ort was made to predict the properties of the b�� states based on extrapolations from the k�� and d�� sectors [ ] [ ]. they are summarized in table . the predicted masses and widths of the two narrow b��u;d states b [b( + = )] and b� [b( + = )] are similar while the j = = states are expected about mev=c lower [ ] and to be broad. the recent experimental data on the d and d � production rate [ ] suggest a value for br(c ! d��) of the order of %. if a similar value holds for br(b ! b��) a clear signal for the decay b�� ! b(�)�� should be visible in the large b hadron sample collected by the aleph experiment. due to the small mass splitting between b� and b mesons only electromagnetic decays of the b� to b are allowed. the photons from the b� decay are very low energy; with a mean of � : gev and a maximum energy of . gev. therefore instead of using the electromagnetic calorimeter (ecal), which has a limited resolution and e�ciency in this low energy region, the tracking system is used to reconstruct and identify converted photons. the b� mass and production rate is measured using a reconstruction method in which these converted photons are associated to selected b jets. the b meson momentum and direction is estimated by assigning particles inside the jet to either the primary or b decay vertex according to their impact parameter and rapidity relative to the jet axis. the technique is extended to a search for b�� states by replacing the photon with a charged particle. throughout the paper nb and nb� refer to the number of primary b (�) mesons. q = u;d q = s state mass width decay mass width decay (jpj ) (gev/c ) (gev) mode (gev/c ) (gev) modes + = . . (b��)l= . < : (b �k)l= + = � : broad (b�)l= � : (bk)l= , b � s + = � : broad (b��)l= � : bs , b � s + = . . (b��)l= , (b�)l= . : (bk)l= , (b �k)l= table : expected properties of l = b�q states. the aleph detector and data sample the aleph detector is described in detail elsewhere [ ]. only a brief description of the apparatus is given here. charged particles are tracked with three devices inside a superconducting solenoid which provides an axial �eld of . tesla. closest to the beampipe is the vertex detector (vdet), installed in , which consists of silicon wafers with strip readout in two dimensions, arranged in two cylindrical layers at average radii . and . cm. this detector covers an angular range down to jcos �j < : for the inner layer and jcos �j < : for the outer layer. the point resolution is �m at normal incidence in the r� and z coordinates. surrounding the vdet is the inner tracking chamber (itc), a drift chamber giving up to eight measurements in r�. outside the itc, the time projection chamber (tpc) provides up to space points for jcos�j < : , and a decreasing number of points for smaller angles, with four at jcos �j = : . for tracks measured by all three devices a momentum resolution of �p=p = : p (gev=c)� is obtained for gev=c muons. the tpc also gives up to measurements of the speci�c ionization of each charged track, with a measured de=dx resolution of . % for bhabha electrons having ionization samples. the ecal was used in combination with the hadronic calorimeter (hcal) to measure the energy of neutral particles produced in hadronic z decays to reconstruct the b-hadron momentum. a total sample of million hadronic z decays recorded by the aleph detector in the years through is used in this analysis. the monte carlo simulation used to determine e�ciencies and estimate backgrounds is based on dymu [ ] and the jetset . parton shower monte carlo [ ]. the decay modes of the b- and d-hadrons are adjusted to agree with the most recent experimental results. a lifetime of . ps is assumed for all b hadrons. detector e�ects are simulated with a detailed model of the material and detector response, based on the geant . package [ ]. selection and reconstruction of b hadrons b hadrons are tagged using the algorithm described in ref.[ ], in which the impact parameters of charged tracks are used to select long lived particles. in a �rst step the events are divided into jets using the jade algorithm [ ] with a y-cut of . . then the probability pt for a charged track to belong to the primary vertex based on its signed impact parameter is calculated. this is the input to compute for each jet the probability pj that a given collection of tracks has no decay products from long-lived particles. requiring pj to be less than a given value increases the likelihood that the event contains long-lived particles. the jet probabilities pj are combined to form an event probability pe. as only the relative production rates of b� and b�� mesons per b meson are determined, the value of the b purity estimated from the monte carlo simulation is su�cient while the absolute b tagging e�ciency is not needed. due to the di�erent requirements of the b� ! b and b�� ! b(�)�� searches, di�erent cuts on pe and pj are used (section and ). but in both cases the analysis is performed in a preselected sample of b events with a purity of %, a sample which was also used to develop a method for the inclusive reconstruction of b hadrons. for charged particles two quantities are used to decide whether they belong to the primary vertex or the b decay vertex: the track probability pt as obtained from the signed impact parameter and the rapidity computed relative to the jet axis. the di�erent rapidity distributions for particles from b decays compared to particles from the primary fragmentation process (see fig. a) can also be used to classify neutral particles. for this purpose the pion mass is assigned to all charged particles while the neutrals are treated as massless. a simple cut in pt (� : � pt � : ) and in rapidity is used to decide whether a particle in the jet belongs to the b hadron or not. from monte carlo studies it is found that the best resolution on the b hadron direction and momentum is achieved by placing this cut at a rapidity value of . for charged and neutral tracks. in order to reduce poorly measured b jets a reconstructed b hadron mass (fig. b) between and gev=c and a measured jet energy normalized to the beam energy (fig. c) between . and . is required. to account for neutrino losses, detector ine�ciencies and wrong mass assignments a correction dependent on the measured b hadron mass and relative jet energy is applied, as determined from the monte carlo simulation. this improves the relative b momentum resolution signi�cantly, although for b jets with a low estimate for the b hadron momentum the resolution for the direction and the momentum is still poor. a minimum reconstructed b hadron momentum of pb > gev=c is therefore required. with this procedure one �nds for the remaining b hadrons a momentum resolution function with an rms of . %. % of the b hadrons have a momentum resolution of % while the rest constitute a non-gaussian tail towards higher estimated momenta. the resolution function for the b direction can be parameterized by a double gaussian with rms widths of mrad for % of the b hadrons and mrad for the remaining %. a comparison of the reconstructed b hadron momentum spectrum in data and monte carlo is shown in fig. d. while both distributions have the same mean value the shapes are slightly di�erent. the monte carlo events are therefore reweighted to match the data and the resulting di�erence in masses and production rates of b� and b�� mesons is included in the systematic errors. reconstruction of converted photons the probability for photon conversions in the material in front of the ecal varies from � % at � to the beam axis to � % at �. the material in the vdet detector and at the itc-tpc wall are the two dominant sources for photon conversions. in a �rst step a general v search in the event is applied [ ]. reconstructed v 's are identi�ed according to their mass as k 's, �'s or photons. in a next step the knowledge that most of the converted photons should have their origin close to the primary vertex is used to increase the reconstruction e�ciency compared to the general v search. the geometrical signature for an electron or positron to originate from a photon conversion is a point (r;�;�) along its reconstructed track where the tangent is pointing to the photon production point, which is for this analysis the event main vertex (see fig. a). all such tracks in an event are selected. pairs of oppositely charged tracks which ful�ll the following criteria are accepted to originate from a converted photon: the sign is given to pt according to the sign of the impact parameter. � the two conversion points (ri;�i;�i) ful�ll j� �� j � : rad and j� �� j � : rad. � the mean conversion radius, (r + r )= , is larger than cm and less than cm. � at least one of the two tracks has no measured coordinate between the interaction point and the mean conversion point. � if particle identi�cation information is available from de=dx it has to be compatible (probability > . %) for at least one of the two tracks with the electron hypothesis. corrections are applied to the photon energy for the energy loss of the electron and positron in the material between the conversion point and the tpc. the relative energy resolution of the accepted pairs is . % and the angular resolution is mrad in � and �. for low energy photons, which are of special interest for this analysis, it is very likely that only one track from the conversion electron-positron pair has a large enough momentum to be seen in the tpc. therefore in the third step those tracks which pass the following cuts are accepted as originating from a photon conversion: � the signi�cance of the conversion point to be di�erent from the main vertex is at least sigma. � if particle identi�cation information is available from de=dx it has to be compatible (probability > : %) with the electron hypothesis. � if the electron probability from the de=dx measurement is less than % the conversion radius has to be larger than cm. � the track has no measured coordinate between the interaction point and the conversion point. the direction of the photon is determined by the conversion point (r;�;�) with a precision of mrad in � and �. for the lost track from the electron-positron conversion pair an energy correction of mev/sin� is applied, as determined from the monte carlo simulation. in the same way as for the conversion pairs the energy loss due to the material between the conversion point and the tpc is corrected. the relative energy resolution for the conversions reconstructed from only a single track is � %. the calibration of the converted photons is tested in data and monte carlo using photons from � decays. the invariant mass spectrum is shown in fig. b using two converted photons. one photon is fully reconstructed and for the second photon an energy of less than gev is required in order to have a similar sample composition as for the b� ! b analysis. the measured � mass is ( : � : � : ) mev=c , in agreement with the expected value. the systematic error re ects the uncertainty due to the choice of the background parametrization. the total error of . % is used as an absolute systematic error on the energy scale in the b� ! b analysis. the e�ciency to reconstruct a photon conversion as a function of energy is shown in fig. c. the purity is nearly %. the radial distribution of conversion points in data and monte carlo is shown in fig. d. the absolute rate of reconstructed converted photons in data and monte carlo di�er by [ : � : (stat:)]%. the decay b� ! b events enriched in b hadrons are selected by requiring an event probability of pe � : � � according to the lifetime tag algorithm [ ]. for jets which in addition passed the b hadron momentum reconstruction as discussed in section , a b quark purity of % is obtained from the monte carlo simulation. in these events the reconstructed b momentum vectors are combined with all converted photons which have an angle � relative to the b meson direction satisfying cos � � : and an energy between . and gev. to reduce the combinatorial background a cut on the photon helicity angle in the b� rest frame, cos�� , is applied. a at distribution is expected for photons from b� ! b decay (see section . ), while the combinatorial background peaks in this distribution at � . in the monte carlo simulation event samples with b�-b mass di�erences between and mev=c were generated. the reconstructed b� mass is always within � (statistical error only) of the nominal value. the b -b-mass distribution obtained from { data is shown in fig. . the expected background from the monte carlo simulation is shown as a hatched area scaled to the same number of q�q-events. the background is dominated by photons from � decays. no particular source of neutral pions dominates the background. the inclusive � momentum spectrum in z decays is described well [ ] by the jetset program used in the aleph monte carlo simulation. converted photons can be measured down to energies of mev. this allows a comparison of the background shape in data and monte carlo on both sides of the peak. the background-subtracted distribution (fig. b) can be approximated by a simple gaussian. the �tted number of b� mesons is n(b�) = � � : ( ) the b�-b-mass splitting is measured to be �m = m(b�) � m(b) = ( : � : � : ) mev=c : ( ) the systematic errors arise from the following sources: � the di�erence in the reconstructed b hadron momentum spectrum (fig. d) in data and monte carlo and the discrepancy of the photon spectra obtained in the sideband region of the b� signal is used to reweight the monte carlo events to match the data. for photon energies between . and . gev excellent agreement between the photon spectrum in data and monte carlo is observed while the maximum deviation at higher photon energies is % at gev. the systematic uncertainty on n(b�) obtained is � , and the e�ect on �m is negligible. � the limited monte carlo statistics for the background subtraction results in a systematic error of � on n(b�) and � : mev=c on �m. � the variation of the required reconstructed minimum b momentum between and gev=c causes a variation in �m by � : mev=c . the e�ect on the relative b� production rate is discussed in section . . � a systematic error of : % is assigned to the absolute energy scale of the reconstructed photons from the study of the � signal. the rms width of the resulting b� signal is ( : � : ) mev=c in data and ( : � : ) mev=c in monte carlo. it is dominated for conversion pairs by the measurement of the b meson direction. for conversions reconstructed only from a single track, which account for � % of the signal, the energy and direction resolution of the photon and b meson contribute similarly to the width of the b� signal. within the experimental resolution it is not possible to separate the b�u, b � d and b � s states, thus the quoted numbers are an average weighted by the production rates of the b� states. . b� production rate the measured number of b� mesons, n(b�), is related to the relative production rate of b� mesons in z decays by the following expression: n(b�) = ntag �b � fb nb� nb + nb� ( ) where ntag is the number of tagged b jets, �b is the b event purity, � is the photon reconstruction e�ciency, fb is the fraction of b mesons produced in z ! b�b decays estimated to be fb = ( : � : )% [ ] and nb�=(nb + nb�) is the relative production probability of vector b mesons. from a data sample of nq�q = ; ; candidate q�q events ntag = ; b jets are selected in which � � b� mesons are reconstructed. with the photon conversion and reconstruction probability � = ( : � : )% and the b purity �b = ( � )% taken from the monte carlo simulation, a relative b� production rate of nb� nb� + nb = ( : � : � : )% ( ) is found. the systematic error of % on �b is derived from the stability plot of the relative b� production rate as a function of the b purity (fig. b). several studies were done to determine the systematic uncertainty of the photon e�ciency: � the agreement of the total conversion rate between data and monte carlo (see fig. d) is [ : � : (stat:)]%. the systematic uncertainty of the photon e�ciency due to a di�erent material distribution or reconstruction e�ciency for converted photons in data and monte carlo is estimated to be % from studies using the well known tpc gas to normalize the conversion rate. � the normalization factor for the background from the monte carlo simulation obtained in the sideband region (m(b ) � m(b) < : gev=c ; : < m(b ) � m(b) < : gev=c ) of the b� signal is found to be : � : . this % deviation from unity can have its origin either in a wrong b tagging e�ciency, a wrong � production rate or a wrong photon reconstruction e�ciency in the monte carlo simulation. the b tagging e�ciency is checked in data and monte carlo by comparing the number of single and double tagged events (nt and ntt). the result is ( ntt=nt) data=( ntt=nt) mc = : � : . to be conservative the % deviation from unity in the background error absolute error on source nb�=(nb� + nb) monte carlo weighting . % monte carlo statistics . % b purity . % e�ciency . % fb . % variation of all cuts . % total (quadratic sum) . % table : contributions to the systematic error on the relative b� production rate. normalization is assigned as a systematic error on the photon detection e�ciency since a wrong � production rate in the monte carlo simulation would not e�ect the extracted b� production rate. � the reconstruction e�ciency for converted photons is energy dependent (see fig. c). therefore a variation of the b�-b mass di�erence changes the photon e�ciency. in order to estimate this e�ect the b�-b mass di�erence was varied in the monte carlo simulation by � mev=c . the resulting uncertainty in the photon e�ciency is � %. a complete breakdown of the quoted systematic error is given in table . all cuts applied in this analysis are varied within reasonable ranges and the variation of the result is included in the systematic error. . b� polarization the decay angle of the photon in the b� rest frame �� can be used to distinguish between transverse (helicity � ) and longitudinal (helicity ) polarized b� mesons, which have the di�erential cross sections �t / ( + cos ��)= and �l / sin �� respectively. if the helicity states are equally populated, i.e. �t : �l = : , a at helicity angle distribution is expected. for this measurement the cos�� range is extended down to � : to increase the sensitivity. the number of b� mesons is determined in bins of cos��. the e�ciency-corrected result is shown in fig. . the relative longitudinal contribution is determined from the �t to be �l �l + �t = ( � � )%; ( ) in agreement with the expectation of = for equally populated helicity states. the systematic error re ects the uncertainty on the photon e�ciency as a function of the photon energy, which is highly correlated with cos ��. the decay b��u;d ! b (�)�� for the b�� search, the photon is replaced by a charged pion. this pion is called in the following ��. the photon from the decay b�� ! b��;b� ! b is lost. only a small fraction of b� mesons (� %) are expected to originate from b�� decays. therefore the search for b�� states starting with a reconstructed b� ! b ; ! e+e� decay would reduce the signal by a large factor but not a�ect the background level. also no improvement for the signal width is expected, due to the fact that the photon is of such low energy compared to the �� in the b�� rest frame that the photon lost in the decay chain only shifts the e�ective mass of the (b��) system down by mev=c from the true b�� mass, but does not broaden the signal signi�cantly. the b�� has a negligible lifetime compared to the average b hadron. this allows to reduce the combinatorial background using the signed impact parameter to distinguish between tracks from the primary vertex and tracks originating from the long lived b hadron decay. in order to be able to assign charged tracks with high purity to either the primary- or the b decay vertex, jets are selected which have a probability of pj � : � � to contain no long lived hadron and a reconstructed b hadron with a momentum of more than gev/c. in addition strict track selection cuts for the �� candidates are applied: � to have at least tpc hits and at least vdet hit, � to originate from a cylindrical region of cm radius and length cm centered around the interaction point, � to have a � per degree of freedom from the track �t of less than and to have a momentum of more than . gev/c, � to have a de=dx measurement in the tpc which is consistent with a pion (probability > %), � to have a probability of jptj � : to originate from the primary vertex, � to be in a cone around the reconstructed b hadron direction of degree. in the monte carlo simulation, b�� mesons were generated with mass di�erences relative to the b meson between and mev=c and reconstructed within � (statistical error only) of the nominal value. the distribution of the b��-b mass di�erence obtained from the { aleph data is shown in fig. a. the background is estimated from the monte carlo simulation and normalized in the sideband regions (m(b�)�m(b) < : gev=c ; : < m(b�)�m(b) < : gev=c ) of the b�� signal. as is shown in ref. [ ] the jetset . [ ] modeling of the pion spectrum from b decays is poor for pions which are soft in the b rest frame. in the low �m region these soft pions account for a sizable fraction of the background (see fig. a). therefore the monte carlo data as shown in fig. are reweighted according to the observed di�erence between the inclusive pion spectrum from b decays as measured by argus [ ] and that generated in the aleph monte carlo. as can be seen from fig. a the shape of the background is reproduced well on both sides of the signal after this procedure. the background-subtracted signal is �tted by a simple gaussian. a resonance structure in the m(b�) � m(b) distribution is observed at m(b�) � m(b) = ( � � ) mev=c : ( ) it has a width of �(�m) = ( � � ) mev=c ( ) and the number of reconstructed b�� decays to b(�)�� is n(b��) = � � : ( ) the shape and the normalization of the background is the dominant source for the quoted systematic errors. to estimate them the following studies are performed: � the monte carlo data are reweighted according to the observed di�erence in the reconstructed b momentum spectrum (fig. d). the e�ect is negligible. � the peterson fragmentation parameter �b is varied in the range : � : in the monte carlo simulation. this changes the yield by � events and has no e�ect on �m or �(�m). � the limited monte carlo statistics of . million hadronic z events and the normalization of the background in the sideband region of the b�� signal account for a systematic error of � on the yield, of � mev=c on �m, and of � mev=c on �(�m). � the complete analysis is repeated several times with di�erent sets of b- and ��- selection cuts. the minimum b momentum cut is varied from to gev/c, the jet selection cut pj in the range � � � � � , the minimum momentum cut for �� from : to gev/c, and the cut on pt in the range : � jp cut t j � : . finally, in order to study the in uence of the unknown helicity structure of the b�� states, the �� candidate sample is divided in two helicity bins, cos �� and cos� � �� < , which leads to the dominant systematic error on �m. the quoted systematic errors on m(b�) � m(b) and �(�m) correspond to half of the observed variation in each case. the relative systematic error on the �� e�ciency estimated from these studies is : % (table ). . b�� mass and production rate the �tted signal width is larger than the detector resolution of mev=c . it is interpreted as a superposition of several b�� states and/or decay modes as observed for the p-wave d meson states [ ] and as predicted for the excited b states [ ]. possible contributions of b��s decays into bu;dk �, with the kaon misidenti�ed as a pion, are expected from a monte carlo simulation to be only of the order of %. they are considered for the b��u;d production rate. in order to arrive at a b��u;d mass value and production rate, assumptions must be made on the relative production rates and decay modes of the four di�erent expected b��u;d states. following spin counting arguments and heavy quark e�ective theory [ ], the relative production rates are expected to be b : b � : b � : b � � : : : . a model based on the predictions for the narrow b��u;d states (see table ) from ref. [ ], i.e., m(b� ) � m(b ) = mev=c , br(b� ! b�) = br(b � ! b ��) = %, br(b ! b ��) = % and �(b� ) � �(b ) is used to describe the b �� signal. for the �t procedure the yield, the mass, and the width of the b� state are taken as free parameters while the detector resolution is �xed according to the monte carlo expectation. the following numbers are obtained (see fig. a): n(b��) = � , m(b� ) = ( � ) mev=c and �(b� ) = ( � ) mev=c . the quoted errors are statistical only. the large theoretical uncertainties do not allow to quote any meaningful systematic error with the current experimental resolution. the sensitivity to the width of the b� state is small since the signal width is dominated by the detector resolution of mev=c . the width is in agreement with the expectation of mev=c from ref. [ ]. the signal is therefore interpreted as arising from the decays of the narrow b��u;d states. however the relative production rates, masses and widths of the broad b��u;d states are unknown. their possible contribution to the signal has to be estimated in order to calculate a b��u;d production rate. attempts to constrain the masses and widths of the broad b �� u;d states from the experimental data were not successful. a resonance structure with an intrinsic width of a few hundred mev=c could not be separated from a monte carlo estimate of the background with the procedure used in this analysis. on the other hand broad b��u;d states with width and mass splitting relative to the narrow b��u;d states of for example mev/c (see fig. b) and a production rate following spin counting can not be excluded with the observed signal. the unknown properties of the broad b��u;d states are therefore included in the systematic uncertainty of the b��u;d production rate. in the notation of section . , the relative b��u;d production rate is given by br(z ! b ! b��u;d) br(z ! b ! bu;d) = n(b��) f(b��u;d) �b ntag �� fbu;d fn(b �� u;d) : ( ) where f(b��u;d) is fraction of b �� u;d in the obtained b �� signal, �� is the � �� e�ciency, fbu;d is the fraction of bu;d mesons produced in z ! b�b decays estimated to be fbu;d = ( : � : )% [ ] and fn(b �� u;d) is the fraction of reconstructed narrow b �� u;d states. from nq�q = ; ; q�q events ntag = ; b jets are selected in which � � b�� mesons are reconstructed. the signal can be parameterized with equal goodness of �t using a single gaussian (model i), the model for the production of narrow b�� states according to ref. [ ] (model ii), or using a single breit-wigner folded with the detector resolution (model iii). the value obtained using model ii is closest to the number extracted from simply counting the excess in the signal region and is between the yield obtained from the other two models. it is % larger than the estimated number of events from the single gaussian �t due to non gaussian tails which are expected for most b�� production models. to account for the unknown signal shape a scaling factor of : � : is therefore applied to the yield extracted from the gaussian �t. f(b��u;d) is estimated from the monte carlo simulation to be : � : . the contamination from b��s decays to bk � is small as a de=dx probability of larger than % for the pion hypothesis is required for the �� candidates. the expected fraction of narrow b��u;d states is: � fn(b �� u;d) = = : only narrow states contribute to the signal and the production rate follows state counting. � fn(b �� u;d) = = : only narrow states contribute to the signal and the production rate follows spin counting. � fn(b �� u;d) = : : broad and narrow states contribute with equal e�ciency to the signal. error absolute error on source br(z ! b ! b��u;d)=br(z ! b ! bu;d) background normalization . % variation of �b . % variation of all cuts . % signal shape . % b��s contribution . % �� momentum cut . % b purity . % p(b ! bu;d) . % total (quadratic sum) . % table : contributions to the systematic error on the relative b�� production rate. fn(b �� u;d) can take any value between = and if the reconstruction e�ciency for broad and narrow b��u;d is di�erent. the most likely scenario corresponds to fn(b �� u;d) = = and hence fn(b �� u;d) = : + : � : is used in the following. the error corresponds to half of the possible spread. the pion e�ciency �� = ( : � : )% and the b purity �b = ( : � : )% are taken from the monte carlo simulation. with these numbers the following relative b��u;d production rate br(z ! b ! b��u;d) br(z ! b ! bu;d) = [ : � : (stat) � : (syst) + : � : (model)]% ( ) is found. the third error re ects the uncertainty due to the unknown value of fn(b �� u;d). in this result the assumption is made that = of all b��u;d mesons decay into charged pions and = into (unobserved) neutral pions. possible decay modes into b� are expected to be small due to the limited phase space. the stability of the result is shown in fig. b as a function of the b purity. only the relative statistical errors with respect to the nominal cut are plotted. a breakdown of the total systematic error is given in table . the momentum cut of . gev/c for the �� leads to an uncertainty of % on the �� e�ciency due to the fact that it is not known which b��u;d states contribute to the observed signal. summary and conclusions using the known decay b� ! b , a method for the inclusive reconstruction of b hadron decays was developed. the following measurements for the b� state are obtained nb� nb� + nb = ( : � : � : )%; ( ) m(b�) � m(b) = ( : � : � : ) mev=c ; ( ) �l �l + �t = ( � � ):% ( ) in agreement with the expectation from a spin counting picture and with the recent results from l and delphi [ ]. for the b�-b-mass di�erence a similar precision to the previous measurements by cusb [ ] ( : � : ) mev=c and cleo [ ] ( : � : � : ) mev=c is obtained. combining the b hadron instead with a charged pion yields an enhancement in the b� mass distribution. fitting the resonance structure observed in the background subtracted m(b�) � m(b) distribution with a simple gaussian yields the following parameters: n(b��) = � � ; ( ) m(b�) � m(b) = ( � � ) mev=c ; ( ) �(�m) = ( � � ) mev=c : ( ) the observed signal is interpreted as arising from the narrow b�� states described in ref. [ ], although a contribution from broad states can not be excluded with the current experimental resolution. the relative b��u;d production rate is extracted to be br(z ! b ! b��u;d) br(z ! b ! bu;d) = [ : � : (stat) � : (syst) + : � : (model)]% ( ) where the third error re ects the uncertainty due to di�erent production and decay models for the broad b��u;d states. the measured mass di�erence and production rate is consistent with the recent results from opal [ ] and delphi [ ]. acknowledgements we would like to thank our colleagues of the accelerator divisions at cern for the outstanding performance of the lep machine. thanks are also due to the many engineers, and technical personnel at cern and at the home institutes for their contribution to aleph's success. those of us not from member states wish to thank cern for its hospitality. references [ ] particle data group, phys. rev. d ( ) . [ ] d. buskulic et al. (aleph collaboration), z. phys. c ( ) . [ ] p. avery et al. (cleo collaboration), phys. lett. b ( ) ; f. butler et al. (cleo collaboration), \observation of d ( ) + and d� ( ) +", contributed paper to the international conference on high energy physics, glasgow , ref. gls ; aleph collaboration, \d�� production in z decays", contributed paper to the international conference on high energy physics, glasgow , ref. gls ; delphi collaboration, \study of d, d� and d�� production in z hadronic decays", contributed paper to the international conference on high energy physics, glasgow , ref. gls . [ ] m. gronau, a. nippe and j.l rosner, phys. rev. d ( ) . [ ] e.j. eichten, c.t. hill and c. quigg, phys. rev. lett. ( ) . [ ] d. decamp et al. (aleph collaboration), nucl. instr. meth. a ( ) ; g. batignani et al. (aleph collaboration), nucl. instr. meth. b a ( ) ; d. buskulic et al. (aleph collaboration), nucl. instr. meth. a ( ) . [ ] d. decamp et al. (aleph collaboration), z. phys. c ( ) . [ ] j.e. campagne and r. zitoun, z. phys. c ( ) . [ ] t. sj�ostrand and m. bengtsson, computer physics commun. ( ) . t.sj�ostrand, in \z physics at lep ", ed. g. altarelli et al., cern ep/ - ( ), vol. , . [ ] r. brun et al. \the geant electromagnetic shower program", cern dd/ee/ - ( ). [ ] d. buskulic et al. (aleph collaboration), phys. lett. b ( ) . [ ] c. kleinwort et al. (jade collaboration), z. phys. c ( ) . [ ] m. acciarri et al. (l collaboration), cern-ppe/ - , submitted to phys. lett. b. [ ] d. buskulic et al. (aleph collaboration), \a measurement of jvcbj from �b ! d�+l��l", cern-ppe/ - , to be submitted to phys. lett. b. [ ] h. albrecht et al. (argus collaboration), z. phys. c ( ) . [ ] n. isgur and m.b. wise, phys. lett. b ( ) . m.b. wise, procs. xvi international symposium on lepton and photon interactions, ithaca, new york, , ed. p. drell, d. rubin, p. . [ ] m. acciarri et al. (l collaboration), cern-ppe/ - , submitted to phys. lett. b; p. abreu et al. (delphi collaboration), cern-ppe/ - , submitted to zeit. f. physik c. [ ] j. lee-franzini et al. (cusb collaboration), phys. rev. lett. , ( ). [ ] d.s. akerib et al. (cleo collaboration), phys rev. lett. , ( ). [ ] r. akers et al. (opal collaboration), cern-ppe/ - , submitted to zeit. f. physik c; [ ] p. abreu et al. (delphi collaboration), phys. lett. b ( ) . figure : comparison of data (dots) and monte carlo distributions (curve) normalized to the same number of q�q events. (a) rapidity distribution relative to the jet axis for all tracks (black dots) and charged tracks only (open circles). the di�erent shape of the rapidity distributions for charged tracks from b decays and from the fragmentation process can be seen from the shaded areas. (b){(d) reconstructed b hadron mass, relative jet energy and b hadron momentum. the shaded area shows the background from non-b�b events according to the monte carlo simulation. figure : a) schematic view of a photon conversion in the (x,y)-plane. b) invariant - mass distribution from data (points) and monte carlo (histogram) using converted photons with the energy of one of the photons being less than . gev. the curve shows a �t with a polynominal background and a gaussian signal. c) reconstruction e�ciency for converted photons where the fraction of fully reconstructed conversions is indicated by the lower curve. d) conversion radius distribution in data (points) and monte carlo (histogram). figure : (a) the b -b-mass di�erence from through data using converted photons. the background estimated from the monte carlo simulation, normalized to the same number of q�q-events, is shown by the hatched area. (b) the background subtracted signal for the decay b� ! b �tted with a gaussian (curve). figure : b purity (a), measured b� production rate (b) and mass (c) as a function of the cut on pe. the dotted lines show the total systematic error. the dashed lines in (b) indicate the systematic error due to the uncertainty in the b purity. figure : the acceptance-corrected number of b�-mesons as a function of the photon decay angle (cos��) in the b� rest frame. the dashed and the dotted curves are the contributions from the transverse and longitudinal polarized states. the �t of both contributions to the data points is given by the solid curve. figure : a) the (b�) � b-mass di�erence from through data. the background estimated from the monte carlo simulation is shown by the hatched area. (b) the background-subtracted signal for the decay b�� ! b(�)�� tted with a gaussian (curve). figure : a) comparison of the background subtracted b�� signal with the model from [ ] (curve) for the narrow b�� states. the shaded area shows the generated structure from the two narrow b��u;d states at an arbitrary scale. the lost photon from the b � decay generates the double peak structure. b) the same as a) but with the additional production of broad b��u;d states according to spin counting with a width of mev=c and a mass splitting relative to the narrow states of � mev=c . figure : b purity (a), measured b��u;d production rate (b) and mass (c) as a function of the cut on pj. the dotted lines show the systematic error band. trends in surgical and beauty masks for a cleaner environment cosmetics review trends in surgical and beauty masks for a cleaner environment pierfrancesco morganti , ,*, vladimir e. yudin , gianluca morganti and maria-beatrice coltelli ,* academy of history of health care art, rome, italy department of dermatology, china medical university, shenyang , china institute macromolecular compounds, university of st petersburg, russian academy of science, st. petersburg, russia; yudin@hq.maceo.ru iscd nanoscience center, rome, italy; gianluca.morganti@iscd.it department of civil and industrial engineering, university of pisa, pisa, italy * correspondence: pierfrancesco.morganti@iscd.it (p.m.); maria.beatrice.coltelli@unipi.it (m.-b.c.) received: july ; accepted: august ; published: august �� abstract: the surgical face mask (sfm) is a sheet medical device covering the mouth, nose and chin to protect the medical staff from the spread of respiratory droplets produced by the infective coughing or sneezing of hospitalized patients. on the other hand the beauty face mask (bfm) has been made by the same sheet but with a different aim—to protect the skin from pollution, acting as a hydrating and rejuvenation agent. currently, both masks are made principally by non-biodegradable tissues, utilized to avoid the increasing great pollution invading our planet. due to the diffusion of the current covid- infection rate and the increasing consumption of skin care and beauty products, the waste of these masks, made principally by petrol-derived polymers, is creating further intolerable waste-invaded land and oceans. after an introduction to the aims, differences and market of the various masks, their productive means and ingredients are reported. these news are believed necessary to give the reader the working knowledge of these products, in the context of the bioeconomy, to better understand the innovative tissues proposed and realized by the biobased and biodegradable polymers. thus, the possibility of producing biodegradable sfms and bfms, characterized for their effective antimicrobial and skin repairing activities or hydrating and antiaging activity, respectively. these innovative smart and biodegradable masks are requested from the majority of consumers oriented towards a future green environment. giving this new sense of direction to their production and consumption, it will be possible to reduce the current waste, ranging worldwide at about billion tons per year. keywords: biodegradable polymers; non-woven tissues; electrospinning; biopolyesters; polysaccharides; chitin nanofibrils; lignin; surgical and beauty masks . introduction surgical face masks (sfms) and beauty face masks (bfms) are products made by specialized tissues that have the basic aim of protecting the face from the aggression of microorganisms and pollutants, respectively [ , ]. the global market of face masks may be shared out in two different categories of sheets, used respectively for medical or cosmetic purposes. sfm is a medical device covering the mouth, nose and chin with the purpose of limiting the transition of an infective agent between the hospital staff and the patient [ ]. it is a means that prevents the spread of respiratory droplet produced by coughing or sneezing and protects health care workers and patients from microorganism infection [ ]. cosmetics , , ; doi: . /cosmetics www.mdpi.com/journal/cosmetics http://www.mdpi.com/journal/cosmetics http://www.mdpi.com https://orcid.org/ - - - http://www.mdpi.com/ - / / / ?type=check_update&version= http://dx.doi.org/ . /cosmetics http://www.mdpi.com/journal/cosmetics cosmetics , , of bfm would catch dirt and pollution, providing the contemporary fast deep hydration, replenishment and rejuvenation of the skin, with the aim to ameliorate its general health and appearance [ ]. both the masks are currently produced by layers made generally by fossil-based spun-bond and melt-blown non-woven tissues, or by emerging techniques such as electrospinning or texturized film extrusion technologies [ ]. they are therefore tissue-engineered products, emerging from the convergence of different health care disciplines such as biological science, nanotechnology, material science, information technology, etc. various research studies and the advancements in nanobiotechnology have led to a de novo design and the fabrication of innovative nanoengineered materials and biomaterials [ , ]. thus, by petrol-derived chemistry, many new plastic polymers have been synthesized to produce tissues. natural polymers such as polysaccharide and biobased polymers synthesized from renewable monomers, such as poly(lactic acid) (pla), seem to be a valid alternative to these fossil based versions, as well as polymers obtained by microorganisms like poly(hydroxyalcanoate) (pha). particularly the natural polymers have shown to be useful for producing functional tissues able to mimic the function of the native extracellular matrix (ecm) [ ]. however, all the described classes of polymers are useful in producing tissues, characterized by their different functionalities, biocompatibility and biodegradability [ ]. fossil-derived polymers possess a consolidated processing capability and a low cost, but are not biodegradable. they are characterized by their accumulation and persistence in the environment [ ]. on the other hand, the mentioned natural-derived polymers show performances and industrial possibility to be processed at a lower maturity level, but they are totally biodegraded to safe ingredients. however, polymers and active ingredients used to make sfms and bfms are not the same, because of the different functionalities and activities they should provide to the skin and body. however, in our opinion, it would be necessary to produce all these masks by skin-friendly and ecofriendly raw materials, to protect human health and the environment. sfms and bfms are described in the next sections considering their current prevalent structure and composition and their present and future market. these data can be relevant to give indications to readers about the future perspectives of applied research in these fields, taking into account the actual growth of the bioeconomy. then, the environmental concern linked to both masks is presented in successive section and finally the use of different biopolymers to replace fossil-based materials is discussed in section . the present review wants to give to the reader some general information and views on the use of biobased materials in these applications. . surgical face mask activity and market surgical face masks (sfm) are made principally for medical purposes to protect doctors and health care workers from infections caused by microorganisms. their production and use, notably increased from the year due to the diffusion of covid- , that involved until today, , , affected people, provoking , deaths [ ]. these masks, in fact, acting as a barrier between the wearer and contaminants, are used massively worldwide to reduce the contact with highly infective microorganisms and viruses not only between doctors and health care workers, but also among people worldwide. how are these masks made? produced prevalently by non-woven tissues, they are generically made up of three or four fine layers, able to filter from % to % of materials, having a dimension higher than micron in size [ – ]. the innermost layer absorbs moisture (breath, cough, etc.), the middle layer acts as a filter for infection agents and nanoparticles, while the outer layer is repellent for liquids (water, blood, etc.) [ ]. these tissues are prevalently manufactured by polypropylene (pp) to obtain a non-woven fabric or textured film, respectively, characterized by the different dimensions of their fibers and interfibrillar spaces. among all the petrol-derived polymers (i.e., polyethylene, polyethylene terephthalate, poly-acrylonitrile, etc.) used as materials to produce the various disposable masks in the market, polypropylene (pp) dominates as the second-highest revenue, for its low cost and simplicity in cosmetics , , of processing and usage [ – ]. the advantages of non-woven fabrics over woven fabrics (knitted) are their higher air permeability, higher bacterial filtration efficiency and low manufacturing cost. however, all the sfms, while highly protective against microbiome, fungi and viruses, are often not comfortable for wearers, especially in the mouth and nose areas where the sweat vapor, transformed into liquid droplets, causes skin irritation. at this purpose and for solving this problem, it was proposed, to cover the pp fibers by adsorbent polymers, such as poly (vinyl alcohol) (pva) [ ]. by this method, the pp fibers increase their hydrophilicity so that sweat, absorbed into the fiber, is no more transformed into an irritative liquid. to assure their quality, the surgical disposable masks, as medical devices, have to follow the official standards according to the rules of the ministry of health in different countries, such as europe (eu) [ ] and the world health organization (who) [ ]. these sfms, therefore, are registered products which, having to fulfill particular requirements, report on the label some imposed specifications, such as their ingredients and modality of use, in order to provide sufficient data for the surgical staff, health care workers and other consumers. these masks, in fact, must be controlled for their bacterial barrier and filtration efficiency, breathing capacity, splashing characteristics and flammability resistance, according to the health ministry rules. thus, disposable masks, made by three to four layers and currently used for the covid- pandemia (figure ), are packaged and sterilized, so that their use may prevent the spread of infection better than reusable, non-woven or knitted ones [ , , ]. just to have an idea of the global market insights, the protective mask market value of around usd billion in , is supposed to surpass usd . billion by [ – ]. cosmetics , , x for peer review of however, all the sfms, while highly protective against microbiome, fungi and viruses, are often not comfortable for wearers, especially in the mouth and nose areas where the sweat vapor, transformed into liquid droplets, causes skin irritation. at this purpose and for solving this problem, it was proposed, to cover the pp fibers by adsorbent polymers, such as poly (vinyl alcohol) (pva) [ ]. by this method, the pp fibers increase their hydrophilicity so that sweat, absorbed into the fiber, is no more transformed into an irritative liquid. to assure their quality, the surgical disposable masks, as medical devices, have to follow the official standards according to the rules of the ministry of health in different countries, such as europe (eu) [ ] and the world health organization (who) [ ]. these sfms, therefore, are registered products which, having to fulfill particular requirements, report on the label some imposed specifications, such as their ingredients and modality of use, in order to provide sufficient data for the surgical staff, health care workers and other consumers. these masks, in fact, must be controlled for their bacterial barrier and filtration efficiency, breathing capacity, splashing characteristics and flammability resistance, according to the health ministry rules. thus, disposable masks, made by three to four layers and currently used for the covid- pandemia (figure ), are packaged and sterilized, so that their use may prevent the spread of infection better than reusable, non-woven or knitted ones [ , , ]. just to have an idea of the global market insights, the protective mask market value of around usd billion in , is supposed to surpass usd . billion by [ – ]. on the other hand, the reusable surgical face masks have a reduced filtration power and protection efficiency, due to their frequent washing cycles. in addition, the repeated laundering causes a further waste of energy, generating also more wastewater in the environment. as previously reported non-woven masks, made by two/three layers of tissues and principally used in hospitals, are manufactured worldwide by pp, as the most used polymer (figure ). different are the designs that can be followed. in the reported example of figure , composed of four-layered tissues, the first non-woven layer avoids the ingress of dust-air, the fourth layer in contact with skin has a protective function, while the second and third core layers, have a bacterial filtration capacity of % and a particulate filtration effectiveness of %, usually obtained by melt blown non-woven fabrics. figure . surgical face masks layers. the surgical mask market is continually growing due to the increased number of people driving worldwide its personal usage, because of the growing number of covid- affected patients [ , , ]. these masks, in fact, are used by personal health care personnel at the workplace and by the general public too as protective means against virus outbreaks, air indoor and outdoor’ air figure . surgical face masks layers. on the other hand, the reusable surgical face masks have a reduced filtration power and protection efficiency, due to their frequent washing cycles. in addition, the repeated laundering causes a further waste of energy, generating also more wastewater in the environment. as previously reported non-woven masks, made by two/three layers of tissues and principally used in hospitals, are manufactured worldwide by pp, as the most used polymer (figure ). different are the designs that can be followed. in the reported example of figure , composed of four-layered tissues, the first non-woven layer avoids the ingress of dust-air, the fourth layer in contact with skin has a protective function, while the second and third core layers, have a bacterial filtration capacity of % and a particulate filtration effectiveness of %, usually obtained by melt blown non-woven fabrics. cosmetics , , of the surgical mask market is continually growing due to the increased number of people driving worldwide its personal usage, because of the growing number of covid- affected patients [ , , ]. these masks, in fact, are used by personal health care personnel at the workplace and by the general public too as protective means against virus outbreaks, air indoor and outdoor’ air pollution, vehicle and industrial facility gas emissions, all causes of allergies and cardiovascular, respiratory and other diseases [ ]. the market has been categorized by different companies not only in terms of the economic turnover, size, trends and future challenges of the masks, but also for the raw materials (cotton, polypropylene, paper and others) and the different layers used for their production [ – ]. these research studies cover woven and non-woven masks, protective for dust or microorganisms, respectively. their use, in fact, is also grown because of the general needs of protection from pollution and diseases, connected worldwide to the increasing aging population [ – ]. in conclusion by global newswire, the global market has been estimated at about usd . billion with an expected compound annual growth rate (cagr) of % by [ ], while technavio [ ] reports an incremental growth of usd . billion with an annual cagr of over % from to for the sfms (figure a). figure . (a) the incremental growth of surgical masks [ ]. (b) global surgical masks market share by region in . (c) disposable surgery face masks by application: industrial and personal (by courtesy of granviewresearch [ ]). in terms of countries (figure b), asia pacific was the most attractive region in the disposable face masks market in with a share of . %, due to the increasing population, growing manufacturing and health care facilities in most notably countries such as china and india. north america and the eu are expected to be other major markets, while the middle east, africa and south america are expected to witness a slow growth. the distribution channel by region was segmented into offline shopping, resulting in the largest category in with a market share of . %, while online shopping was used more in the emerging markets [ ]. by application it is possible to distinguish two production categories—industrial, the main category in , and personal (figure c) [ – ]. cosmetics , , of . beauty face masks (bfms) activity and market differently from surgical masks, which have a protective role against microorganisms, beauty masks should mobilize the endogenous skin defense and the cellular detoxification systems, as previously reported [ , , ]. it is supposed, in fact, that beauty masks could increase the skin’s self-defense, becoming more effective and proactive to safeguard the skin ecosystems. as a consequence, bfms could promote the breathing of the skin and normalize the physiological cell turnover, thus preventing the premature aging phenomena (figure ). obviously the selected active ingredients, which can be used to modify the non-woven fibers and the electrospun polymers, have to be different from those used for the sfms. cosmetics , , x for peer review of pollution, vehicle and industrial facility gas emissions, all causes of allergies and cardiovascular, respiratory and other diseases [ ]. figure . (a) the incremental growth of surgical masks [ ]. (b) global surgical masks market share by region in . (c) disposable surgery face masks by application: industrial and personal (by courtesy of granviewresearch [ ]). figure . the normal skin turnover. the market has been categorized by different companies not only in terms of the economic turnover, size, trends and future challenges of the masks, but also for the raw materials (cotton, polypropylene, paper and others) and the different layers used for their production [ – ]. these research studies cover woven and non-woven masks, protective for dust or microorganisms, respectively. their use, in fact, is also grown because of the general needs of protection from pollution and diseases, connected worldwide to the increasing aging population [ – ]. in conclusion by global newswire, the global market has been estimated at about usd . billion with an expected compound annual growth rate (cagr) of % by [ ], while technavio [ ] reports an incremental growth of usd . billion with an annual cagr of over % from to for the sfms (figure a). figure . the normal skin turnover. however bfms, according to their assigned effectiveness, are enclosed into a particular category of the cosmetic global market. thus for this niche of market, which is highly fragmented and competitive, the players are engaging a variety of strategies to produce innovative products. as a consequence, it is possible to recognize seven basic types of face masks with different claiming benefits: clay or mud mask, cream mask, gel mask, peel-off mask, charcoal mask, sleep mask and sheet mask [ , ]. all these specialized cosmetics are principally used to supplement the daily skin care regime routine, ameliorating the skin hydration and the body’ general health and appearance [ , , ]. at this purpose, % of chinese women aged – are using these masks for hydrating the skin, followed by % of consumers that are looking for skin whitening and % for pore refining. differently, among the us consumers, % are looking to treat acne or blemishes and % to slow down the signs of aging, such as fine lines and wrinkles [ , ]. in conclusion, consumers worldwide, suffering from uncertainty also for the recent covid- diffusion, have the need to feel safe more than ever. thus, they are looking for innovative and effective cosmetic products and sheet masks able to ameliorate their appearance and body health, slowing down the stress condition and matching their own skin type and life-style. as a consequence, self-esteem is improved with positive effects on several aspects of the self-image [ ]. regarding the market and according to statista data, the value of sheet facial masks sheared usd . million in , with an estimated increase to usd . million in , as part of the global cosmetic market with a revenue of usd billion in [ ]. differently, allied market research evaluated the same market size at usd million in with an estimated usd . million by with a cagr of . % during the forecast period of – [ ]. cosmetics , , of however, it seems well established that the growth of sheet face masks has been influenced from the increased spending on cosmetic and personal care products, coupled with rising living standards of the consumer’s majority. moreover, these sheet-cosmetics are considered beneficial for their hydrating and antiaging effectiveness, as well as for the possibility to be used while traveling or even doing household chores [ ]. how these masks are made? these cosmetics are generally made of cotton fabric often mixed with synthetic polyesters, biocellulose and other polymers infused with cosmetic active ingredients, to provide long lasting effects, compared to traditional topical serum and hydrogels. they are preferred by consumers because they ready to use and considered to be made of natural ingredients and by new technologies, skin-friendly and ecofriendly. “the increased awareness towards sustainability and environment footprint, in fact, are largely influencing purchase decision of consumers” [ ]. about the regions involved and according to mintel research data, asia pacific dominated the worldwide beauty sheet market and accounted for % with a cagr of . % of all global masks launched in , owing to high product consumption in countries such as south korea and china [ , ] these countries follow the intensive skincare routines in which the application of this sheet mask represents an important step to hydrate the skin quickly, making it soft and glow in the shortest time [ ]. thus, as previously reported, asia pacific accounted for most of the global sheet market ( %), followed by the eu ( %) and usa ( %; figure b) [ ]. however, the more innovative market results in asia pacific with the most launches coming from the north asian region, with china accounting for % of all the global sheet mask’ introductions, followed by taiwan %, south korea %, hong kong % and japan %. about the size, china, japan and south korea are currently the world’s largest facial care market estimated to reach a retail market value of usd . billion, usd . billion and usd . billion respectively [ ], also because a sheet mask is now a frequent feature in many consumers’ skincare routine. at this purpose, % of chinese consumers use masks in the evening before sleeping, while % use them in the morning and during the day also. additionally, % agree that facial beauty masks are the best first-aid skincare products so that % of women aged – used them in the last months [ ]. actually in western countries these masks are gaining in popularity as a regular beauty treatment, also they were used prevalently in an evening routine in the last months: from % of consumers in the uk, % in france, % in germany, % in spain and % in usa. however, north america is projected to exhibit exponential growth throughout , registering the highest % cagr with the supermarket/hyper markets segment dominating and the e-commerce segment estimated to grow at a cagr of . % [ ]. in conclusion, consumers are more concerned about materials and active ingredients used in the manufacturing and packaging of skin care products and beauty face masks, having special attention to skin health and to the environment preservation [ ]. they, in fact, have etched in their minds the concept of zero waste, waterless and safeness. thus, the adoption of innovative and smart technologies and natural ingredients is expected to propel the revenue growth of the overall beauty face mask market, also because this specific cosmetic product is considered multifunctional, with better performances, easy to use and able to give new benefits to the skin’s health [ , , ]. . surgery and beauty face masks: the environment problem although there are many natural polymers present in the market, the majority of surgery and beauty masks and their packaging are made of fossil-derived polymers, the recycling of which is difficult, being not separately collected and sorted [ , ]. unfortunately they are made of non-biodegradable materials, contributing to worsening the worldwide plastic waste pollution (figure ) [ , ] and at the same time increasing greenhouse gas emissions that, from around . billion tons in , will probably be . billion tons by [ ]. moreover, it is not to be forgotten the increasing global production of plastics that, coming from . million metric tons in , increased to billion metric tons in with a consumption per capita of kg, % of which is disposed as waste to landfills [ , ]. cosmetics , , of cosmetics , , x for peer review of foundation in collaboration with the united states environment program, which includes also companies representing % of the global plastic packaging producers. therefore, it is time to produce zero waste, drastically reducing the current consumption of non biodegradable plastic, the waste of which is entering in the food chains with dangerous effects on flora, fauna and humans. estimates suggest, in fact, that annually more than , marine mammals and turtles and over one million sea birds are killed by marine plastic, which, broken down into . trillion of micro-pieces, adsorb toxins, resulting in poisoning of animals that accidentally ingest it [ ]. figure . the pathway by which plastic enters the world’s oceans: estimates of global plastics entering the oceans from land-based sources in (based on data from jambeck et al. [ ]). currently, as previously reported, the problem of plastic waste is further increased by the covid- problem due to the increased use of protective and sanitizing products. a growing number of countries, in fact, are encouraging citizens to wear protective equipment in public to cover the face by masks and protecting the hands by gloves, which have to be cleaned frequently by sanitizing gels, which are unfortunately packed in fossil plastic [ , ]. as a consequence consumers have embraced the clean and health concept, changing their purchase habits. they buy not only more masks, gloves, cleaning solutions and gels, but also more colored cosmetics, rethinking nail and eye care at home and outside, due to the closure of the beauty salons also [ ]. consumers, in fact, wearing masks, try to look more attractive, evidencing their eyes and nails by the use of more colored make-up [ ]. moreover the anxiety, shifting focus to health and safety, encourages consumers to seek protection against outdoor and indoor pollution also, for trying to go back to a more sustainable lifestyle [ ]. thus, the level of air pollutants, which are increasing worldwide, may be considered the real cause of many health-related problems with risks of microbial and viruses’ infections, such as the covid- pandemic, certainly connected also with a wrong way of consumption. in conclusion beauty standards are evolving and customers are appreciating who they are, thus looking for a different way of living, more respectful of both their personal health and the planet’s environment. consequently, “conscious consumers are seeking out to make positive decisions about what they could buy, looking for a solution to the negative impact environment and consumerism are having on the world” [ ]. moreover, they are looking for high quality and high performing cosmetic and figure . the pathway by which plastic enters the world’s oceans: estimates of global plastics entering the oceans from land-based sources in (based on data from jambeck et al. [ ]). therefore, global waste with a value projected to increase to usd billion in will generate billion tons/year of materials, composed of % of consumer products. around % of these materials is represented by plastics, % by textiles and % by food, while the majority of this waste is due to the urbanization population growth and the worldwide economy development [ ]. regarding the regions, % and % of this waste is produced in asia pacific and europe respectively. this high increase, in fact, is directly connected to the wellness economy, which grew annually by . % from to , nearly twice as fast as the economic growth ( . %), increasing to usd . trillion [ ]. just as an example, it has been calculated that only the worldwide personal care and beauty waste increased to usd billion in [ ], producing every year more than billion units of packaging, % of which are not biodegradable. unfortunately this waste material is partially recycled while the majority of them are mainly incinerated. thus, there is a necessity to change the linear economy into a circular economy [ , ] by a more environmentally-friendly approach based on the use of recycled or recyclable, textiles, packaging, surgical and beauty masks. this is the aim of the new plastic economy commitment organized by the ellen macarthur foundation in collaboration with the united states environment program, which includes also companies representing % of the global plastic packaging producers. therefore, it is time to produce zero waste, drastically reducing the current consumption of non biodegradable plastic, the waste of which is entering in the food chains with dangerous effects on flora, fauna and humans. estimates suggest, in fact, that annually more than , marine mammals and turtles and over one million sea birds are killed by marine plastic, which, broken down into . trillion of micro-pieces, adsorb toxins, resulting in poisoning of animals that accidentally ingest it [ ]. currently, as previously reported, the problem of plastic waste is further increased by the covid- problem due to the increased use of protective and sanitizing products. a growing number of countries, in fact, are encouraging citizens to wear protective equipment in public to cover the face by masks and protecting the hands by gloves, which have to be cleaned frequently by sanitizing gels, which are unfortunately packed in fossil plastic [ , ]. as a consequence consumers have embraced the clean and health concept, changing their purchase habits. they buy not only more masks, gloves, cleaning solutions and gels, but also more colored cosmetics, rethinking nail and eye care at home and outside, due to the closure of the beauty salons also [ ]. consumers, in fact, wearing masks, cosmetics , , of try to look more attractive, evidencing their eyes and nails by the use of more colored make-up [ ]. moreover the anxiety, shifting focus to health and safety, encourages consumers to seek protection against outdoor and indoor pollution also, for trying to go back to a more sustainable lifestyle [ ]. thus, the level of air pollutants, which are increasing worldwide, may be considered the real cause of many health-related problems with risks of microbial and viruses’ infections, such as the covid- pandemic, certainly connected also with a wrong way of consumption. in conclusion beauty standards are evolving and customers are appreciating who they are, thus looking for a different way of living, more respectful of both their personal health and the planet’s environment. consequently, “conscious consumers are seeking out to make positive decisions about what they could buy, looking for a solution to the negative impact environment and consumerism are having on the world” [ ]. moreover, they are looking for high quality and high performing cosmetic and healthy products that, made by natural ingredients and sustainable and transparent production, could be able to effectively shift their activities from aging to longevity [ ]. therefore, surgical and beauty face masks, designed and realized by biodegradable natural materials, appear to become an important part of future products requested and purchased from consumers. . innovative renewable and biodegradable polymers for non-woven tissues as previously reported, the world generates around billion tons per year of municipal waste, expected to grow to . billion tons by . in the future the recycling of waste will become mandatory as a pivotal methodology of its management. thus, also a great part of organic waste would be recycled for obtaining natural polymers such as starch, cellulose, lignin and chitin to be used for making biodegradable non-woven tissues and films [ ], suitable to produce innovative sfms and bfms. these biobased polymers are generally processed by standard non-woven industries and by high throughput manufacturing techniques (melt blown, spun bond and casting) [ ]. the electrospinning technology is the most used in cosmetic and regenerative medicine because it may easily create three dimensional fibrous scaffolds, closely imitating the nano-to micro-mesh work of the native extracellular matrix (ecm) [ , – ]. by this technology it seems possible to produce scaffolds mimicking the structure and function of the ecm, necessary to allow the normal function and interaction of the skin cells [ ]. moreover, it is possible to obtain polymeric nanofibers of thin size tissues, characterized for their higher effectiveness because of their high surface to volume ratio and the many interfibrillar nano-dimensioned holes catching the air nanoparticulate. the use of this technique could be an alternative to the traditional production of spun-bonded or melt blown tissues, often used as an external or internal layer of the sfms. however as previously reported, the internal third layer may be obtained generally by the casting technique, by which it is possible to obtain shorter micrometric fibers with less interfibrillar holes, so that both nanoparticles and microorganisms do not have the possibility to pass through (figure ). in any way, the electrospinning is also a very simple technique because it is composed of a unit made by a syringe containing the liquid material consisting of a polymer solution or suspension to be electrospun; a pump that controls the liquid flow rate; a high voltage current supplier; a metal plate collector and a spinneret. naturally the property of the liquid material and the process parameters are crucial for the physical, morphological and biomechanical performance of the electrospun fibers, which may be characterized and varied for their porosity, tunable pore size and high surface-to-volume ratio [ – ]. thus, it is possible to produce different non-woven tissues designed for different purposes and applications. many properties of the biomaterials used and the tissue-scaffolds realized, such as porosity, mechanical properties and degradation behavior, in fact, play a pivotal role for their activity as skin regenerating carriers. the use of biopolymers to produce bfms and sfms, therefore, can be promising and useful as well as the electrospinning technique. in fact, only some biobased polyesters, like pla and its blends, can be extruded into fibers via melt blowing or wet laid processes, while other thermal resistant polymers cosmetics , , of can undergo degradation during these processes. in general, it has been a considerable challenge to convert polyhydroxyalkanoates (pha) copolymers as well as other biodegradable polymers into useful forms by conventional melt methods because, after the melting and cooling down processes, they remain substantially tacky. consequently, there is a need for alternative fiber production methods. often, the only possible routes for making biopolymer fibers are represented by productive processes made at room temperature, thus involving polymer solutions, like electrospinning with the necessity to use biodegradable and ecosustainable solvents. however, to obtain nanostructured tissues the method of election seems to be the electrospinning technique by the use of polymers water-soluble or suspendible, like the polysaccharides-based ones. cosmetics , , x for peer review of use in beauty masks could be useful. some of these polysaccharides, in fact, may be soluble in water like pullulan or insoluble but easily suspendible, such as starch, cellulose or chitin nanofibrils, obtained as a polymer covered by positive charges. however, all these polymers’ results are promising for their possibility to be electrospun in water [ – ]. on the other hand, they are not highly thermally resistant, so their processing by conventional methodologies can be quite difficult. figure . fibers dimension and interfibrillar boles of a chitin nanofibrils (cn)-film at sem. on the contrary the less hydrophilic biopolyesters, such as pla and pha, can easily undergo by conventional processing methodologies to produce non-woven tissues. thus, pla, obtained from polymerization of lactic acid, and pha, obtained from microorganisms, are materials potentially suitable for making sfms and bfms, being fully biobased and biodegradable polymers as well as the commercial biopolyesters poly (caprolactone) (pcl), poly(butylene succinate (pbs) and poly(butylene adipate-co-terephthalate) (pbat) obtained partially by non renewable sources. however, the actual industrial trends are oriented to obtain these polymers from renewable sources only, for having in next years more commercially available fully biobased biopolyesters. lignin, obtained from forestry and agro-food waste, can be considered another useful material in sfm and bfm for its intrinsic antioxidant properties also. moreover, being an electronegative hydrosoluble polymer, forms in water complexes with chitin nanofibrils. these complexes have been studied as potential carriers of active biomolecules for cosmetic and biomedical applications [ ]. all these biobased materials can be considered for producing sfms or bfms so that their applications, advantages and disadvantages are reported in table , where chitin nanofibrils-lignin complexes (cn–lg), pla, pha, pullulan or starch and cellulose were compared, considering their processing properties and end-life, when used as the main materials for this use. among the many polysaccharides and natural polymers, chitin and lignin, seem to represent a good alternative, being obtainable in great quantity from food waste and agro-forestry biomass respectively [ , ]. these polymers are the most abundant natural polymers considered as prospective raw materials suitable to produce green surgical and beauty masks according to our previous research activities [ – ]. moreover both the polymers have shown to have antibacterial, antioxidant and skin regenerative activity, suitable to realize innovative and biodegradable tissues [ – ]. chitin and lignin, being nontoxic compounds that are easily biodegradable, have been used figure . fibers dimension and interfibrillar boles of a chitin nanofibrils (cn)-film at sem. for producing sfms or bfms several biobased materials can be considered. the class of polysaccharides (figure ) consists of very hydrophilic polymers, able to retain water when at the wet state, with the possibility to transfer it to the skin, when in contact with its surface. hence their use in beauty masks could be useful. some of these polysaccharides, in fact, may be soluble in water like pullulan or insoluble but easily suspendible, such as starch, cellulose or chitin nanofibrils, obtained as a polymer covered by positive charges. however, all these polymers’ results are promising for their possibility to be electrospun in water [ – ]. on the other hand, they are not highly thermally resistant, so their processing by conventional methodologies can be quite difficult. on the contrary the less hydrophilic biopolyesters, such as pla and pha, can easily undergo by conventional processing methodologies to produce non-woven tissues. thus, pla, obtained from polymerization of lactic acid, and pha, obtained from microorganisms, are materials potentially suitable for making sfms and bfms, being fully biobased and biodegradable polymers as well as the commercial biopolyesters poly (caprolactone) (pcl), poly(butylene succinate (pbs) and poly(butylene adipate-co-terephthalate) (pbat) obtained partially by non renewable sources. however, the actual industrial trends are oriented to obtain these polymers from renewable sources only, for having in next years more commercially available fully biobased biopolyesters. cosmetics , , of cosmetics , , x for peer review of in their nanosizes (i.e., chitin nanofibrils (cn) and nanolignin (lg)) to increase their effectiveness in realizing non-woven tissues [ ] and films [ , ], because of the higher surface-to-volume ratio in respect to their normal dimensions. their application seems to be more suitable to produce directly bfms by the use of electrospun tissues, characterized for their antioxidant, antimicrobial and cell’s regenerative effectiveness. in the case of sfms, the cn–lg complexes can be used to modify polymeric substrates, through methodologies such as powder impregnation and water based coatings [ ]. interestingly cn–lg complexes can act as carrier of various functional molecules and this possibility was successfully evidenced incorporating into the cn–lg glycyrrhetic acid, extracted from the liquorice plant [ ]. this acid, in fact, possesses evident antimicrobial and anti-inflammatory properties useful for the surgical masks. figure . biopolymers considered for producing a surgical face mask (sfm) and a beauty face mask (bfm). however, it is important to remember that many other common biodegradable polymers used in skin tissue regeneration are either natural or man-made, such as starch, cellulose, gelatin, pullulan or polylactic acid (pla), polyglycolic acid (pga), pga-pla copolymers and polyhydroxyalkanoates (pha). all these polymers, as previously reported, have shown various advantages or disadvantages when used for tissue production but can be adopted in dependence of the desired final properties. pla, for example, has a high modulus of elasticity and tensile strength but shows also inherent brittleness and low toughness [ ]. however, it can be a very good candidate to produce conventional non-woven tissues with a cost similar to the current pp based version. moreover, the recycling of the masks can be possible as well as its composting in industrial plants [ ]. thus, technologies to modulate pla based blend properties [ – ] as well as the incorporation of chitin nanofibrils or other nanostructured fillers [ – ] have yet to be deeply investigated. it has been shown that these fillers potentiate specific properties of pla based materials, just as for instance, the incorporation of chitin nanofibrils [ ]. thus, pure pla or its blends with other biodegradable biopolyesters can be easily processed by traditional non-woven techniques to make sfms. on the one hand, hydrophobicity of pla makes it suitable as a protective external film/tissue to be used as support for the bfms fabrication. on the other hand pla based composites with natural fibers [ – ] or nanocomposites with a higher hydrophilicity can be of utility for producing other suitable layers of non-woven tissues. the advantage of collecting the post-consumer bfm in the organic fraction of waste can improve the end of life of these products with respect to current versions where mixtures of natural and fossil fibers are used and mainly disposed by landfill. figure . biopolymers considered for producing a surgical face mask (sfm) and a beauty face mask (bfm). lignin, obtained from forestry and agro-food waste, can be considered another useful material in sfm and bfm for its intrinsic antioxidant properties also. moreover, being an electronegative hydrosoluble polymer, forms in water complexes with chitin nanofibrils. these complexes have been studied as potential carriers of active biomolecules for cosmetic and biomedical applications [ ]. all these biobased materials can be considered for producing sfms or bfms so that their applications, advantages and disadvantages are reported in table , where chitin nanofibrils-lignin complexes (cn–lg), pla, pha, pullulan or starch and cellulose were compared, considering their processing properties and end-life, when used as the main materials for this use. among the many polysaccharides and natural polymers, chitin and lignin, seem to represent a good alternative, being obtainable in great quantity from food waste and agro-forestry biomass respectively [ , ]. these polymers are the most abundant natural polymers considered as prospective raw materials suitable to produce green surgical and beauty masks according to our previous research activities [ – ]. moreover both the polymers have shown to have antibacterial, antioxidant and skin regenerative activity, suitable to realize innovative and biodegradable tissues [ – ]. chitin and lignin, being nontoxic compounds that are easily biodegradable, have been used in their nanosizes (i.e., chitin nanofibrils (cn) and nanolignin (lg)) to increase their effectiveness in realizing non-woven tissues [ ] and films [ , ], because of the higher surface-to-volume ratio in respect to their normal dimensions. their application seems to be more suitable to produce directly bfms by the use of electrospun tissues, characterized for their antioxidant, antimicrobial and cell’s regenerative effectiveness. in the case of sfms, the cn–lg complexes can be used to modify polymeric substrates, through methodologies such as powder impregnation and water based coatings [ ]. interestingly cn–lg complexes can act as carrier of various functional molecules and this possibility was successfully evidenced incorporating into the cn–lg glycyrrhetic acid, extracted from the liquorice plant [ ]. this acid, in fact, possesses evident antimicrobial and anti-inflammatory properties useful for the surgical masks. however, it is important to remember that many other common biodegradable polymers used in skin tissue regeneration are either natural or man-made, such as starch, cellulose, gelatin, pullulan or polylactic acid (pla), polyglycolic acid (pga), pga-pla copolymers and polyhydroxyalkanoates (pha). all these polymers, as previously reported, have shown various advantages or disadvantages when used for tissue production but can be adopted in dependence of cosmetics , , of the desired final properties. pla, for example, has a high modulus of elasticity and tensile strength but shows also inherent brittleness and low toughness [ ]. however, it can be a very good candidate to produce conventional non-woven tissues with a cost similar to the current pp based version. moreover, the recycling of the masks can be possible as well as its composting in industrial plants [ ]. thus, technologies to modulate pla based blend properties [ – ] as well as the incorporation of chitin nanofibrils or other nanostructured fillers [ – ] have yet to be deeply investigated. it has been shown that these fillers potentiate specific properties of pla based materials, just as for instance, the incorporation of chitin nanofibrils [ ]. thus, pure pla or its blends with other biodegradable biopolyesters can be easily processed by traditional non-woven techniques to make sfms. table . fully renewable and biodegradable polymers highly compatible with skin that can be used in surgery face masks (sfm) or beauty face masks (bfm). mask cn-ln pla pha pullulan or starch cellulose sfm x x x x advantages -compostable -easily processable by electrospinning -antimicrobial -antioxidant -easily processable -recyclable -compostable -slightly antimicrobial -cheap -recyclable -compostable in marine environment -easily processable -cheap disadvantages none compostable only in composting plant -not easily processable -soluble or swelling in water -low resistance to water vapor bfm x x x x x advantages -compostable -easily processable by electrospinning -antimicrobial, -antioxidant -regenerative for skin cells -cheap and compostable -compostable in marine environment -efficient release of actives -compostable -easily processable by electrospinning -removal with water (no solid waste) -easily processable -cheap disadvantages none -hydrophobic -it needs adding actives -not easily processable -it needs adding actives -it needs adding actives it needs adding actives cn–lg = chitin nanofibrils-lignin complexes; pla = poly(lactic acid); pha = poly(hydroxyalcanoate); sfm = surgical face masks (sfm); bfm = beauty face masks (bfm). on the one hand, hydrophobicity of pla makes it suitable as a protective external film/tissue to be used as support for the bfms fabrication. on the other hand pla based composites with natural fibers [ – ] or nanocomposites with a higher hydrophilicity can be of utility for producing other suitable layers of non-woven tissues. the advantage of collecting the post-consumer bfm in the organic fraction of waste can improve the end of life of these products with respect to current versions where mixtures of natural and fossil fibers are used and mainly disposed by landfill. pla does not have intrinsic functional properties, although a slight antimicrobial behavior was evidenced [ , ] and attributed to the presence on its surface of a low concentration of lactic acid, known as a biocide. hence the coating of pla non-woven and their substrates with functional compounds incorporating antioxidant, anti-inflammatory and skin regenerative properties, seems to be a relevant process, yet studied by several authors. miletić et al. [ ] developed active coatings with modified and unmodified chitin–lignin nanoparticle complexes to apply them on extruded pla-based sheets. on the other hand, the use of pha can result in the advantage of a tissue or film that should have a very high compatibility with skin, as demonstrated in research studies where compression molded or extruded pha/starch bfms based elastic films were produced, with starch acting as a carrier to cosmetics , , of be applied on the skin [ , ]. the pha provides the possibility to degrade the mask also in the marine environment [ ]. so, in the case that the mask is accidentally lost in the environment, this can be an advantage against littering and marine pollution. unfortunately, its very narrow processing temperature range may limit its application in several fields. the use of pullulan [ ] or starch results in not being suitable for the sfms, because these biopolymers are soluble or easily swell out in water. hence the water vapor of human breathing can induce the partial dissolution of the mask. on the other hand, these polymers are much more interesting for the use in bfms, as they can produce tissues that dissolve on the wet skin, rapidly releasing the biodegradable cosmetic active ingredients. moreover, they do not induce the production of solid waste, as they can be removed by washing the skin. cellulose may be another cheap alternative to process both sfms and bfms by consolidated technologies. however, its hygroscopicity can induce some instability due to the water vapor of breathing and the cellulose fibers, which tend to be pulped by water. anyway, for a beauty mask pure cellulose seems to be a valid and good support. among the biobased, biodegradable and coating materials, chitin nanofibrils can be used as a functional additive for tissues, such as for example pla films [ ] or cellulosic substrates [ ]. it is also interesting to underline that chitin nanofibrils have been shown to increase not only the tensile strength and young modulus of various composites made, for example by chitosan [ , ] or polylactic acid (pla) [ , ], but also to stimulate the skin differentiation and maturation of cd -posive cells of rats with the characteristics of stem cells, for example, at the level of the hair bulb (figure ) [ ]. as it appears from the reported immuno-histochemical study, the cd -positive cells appear to be more expressed in skin treated by cn and cn-lutein compared with the non-treated control (figure ). cosmetics , , x for peer review of pla does not have intrinsic functional properties, although a slight antimicrobial behavior was evidenced [ , ] and attributed to the presence on its surface of a low concentration of lactic acid, known as a biocide. hence the coating of pla non-woven and their substrates with functional compounds incorporating antioxidant, anti-inflammatory and skin regenerative properties, seems to be a relevant process, yet studied by several authors. miletić et al. [ ] developed active coatings with modified and unmodified chitin–lignin nanoparticle complexes to apply them on extruded pla- based sheets. on the other hand, the use of pha can result in the advantage of a tissue or film that should have a very high compatibility with skin, as demonstrated in research studies where compression molded or extruded pha/starch bfms based elastic films were produced, with starch acting as a carrier to be applied on the skin [ , ]. the pha provides the possibility to degrade the mask also in the marine environment [ ]. so, in the case that the mask is accidentally lost in the environment, this can be an advantage against littering and marine pollution. unfortunately, its very narrow processing temperature range may limit its application in several fields. the use of pullulan [ ] or starch results in not being suitable for the sfms, because these biopolymers are soluble or easily swell out in water. hence the water vapor of human breathing can induce the partial dissolution of the mask. on the other hand, these polymers are much more interesting for the use in bfms, as they can produce tissues that dissolve on the wet skin, rapidly releasing the biodegradable cosmetic active ingredients. moreover, they do not induce the production of solid waste, as they can be removed by washing the skin. cellulose may be another cheap alternative to process both sfms and bfms by consolidated technologies. however, its hygroscopicity can induce some instability due to the water vapor of breathing and the cellulose fibers, which tend to be pulped by water. anyway, for a beauty mask pure cellulose seems to be a valid and good support. among the biobased, biodegradable and coating materials, chitin nanofibrils can be used as a functional additive for tissues, such as for example pla films [ ] or cellulosic substrates [ ]. it is also interesting to underline that chitin nanofibrils have been shown to increase not only the tensile strength and young modulus of various composites made, for example by chitosan [ , ] or polylactic acid (pla) [ , ], but also to stimulate the skin differentiation and maturation of cd - posive cells of rats with the characteristics of stem cells, for example, at the level of the hair bulb (figure ) [ ]. as it appears from the reported immuno-histochemical study, the cd -positive cells appear to be more expressed in skin treated by cn and cn-lutein compared with the non-treated control (figure ). figure . faster stem cells reproduction onto hair treated by chitin nanofibrils binding lutein [ ]. on the other hand, the interesting stimulus activity on cd- -positive radicular-follicular (i.e., stem) cells reported from our group some years ago [ ] has been confirmed recently from other research groups [ – ]. thus, it has shown an increasing activity of anagen hair follicles of mice treated topically by chitosan and cn with a contemporary decrease in the number of catagen follicles, compared with the control group [ ]. additionally, it has shown a faster repairing activity on wounded and burned skin of mice and humans skin treated by cn tissue [ – ]. the activity on the stem cell could be one of the probable reasons of the skin repairing activity shown from cn tissues, used in vivo by surgical medications to repair the skin affected by burns of the first and second degree [ , ]. it has been shown, in fact, a faster repairing activity of the burned skin treated by cn tissues in comparison with the normal medication in use into the plastic surgery hospital department [ ]. figure . faster stem cells reproduction onto hair treated by chitin nanofibrils binding lutein [ ]. on the other hand, the interesting stimulus activity on cd- -positive radicular-follicular (i.e., stem) cells reported from our group some years ago [ ] has been confirmed recently from other research groups [ – ]. thus, it has shown an increasing activity of anagen hair follicles of mice treated topically by chitosan and cn with a contemporary decrease in the number of catagen follicles, compared with the control group [ ]. additionally, it has shown a faster repairing activity on wounded and burned skin of mice and humans skin treated by cn tissue [ – ]. the activity on the stem cell could be one of the probable reasons of the skin repairing activity shown from cn tissues, used in vivo by surgical medications to repair the skin affected by burns of the first and second degree [ , ]. it has been shown, in fact, a faster repairing activity of the burned skin treated by cn tissues in comparison with the normal medication in use into the plastic surgery hospital department [ ]. what is the reason of the reinforcing activity of chitin nanofibrils when used as a filler to realize nanocomposites with chitosan [ ] or polylactic acid [ , , ]. according to the yudin group research studies [ ], it has been supposed that cn “contributes to the orientation of the chitosan macromolecule that leads to an increased strength and elastic young module of the composite fibers” as reported on figure , contributing also to the degradability and sustainability of the nanocomposite processing [ , , , ]. the introduction of cn into the chitosan matrix could contribute to form a more bioresorbable composite, increasing its biocompatibility, bioactivity, hemocompatibility and effectiveness at the skin level [ , – ]. cosmetics , , of cosmetics , , x for peer review of connected to each other with a morphology characterized by many holes, may facilitate the interchanging of oxygen and carbon dioxide with the cells. figure . nanocomposite structure organization made by chitosan fibers (green) and chitin nanofibrils (blue) [ ]. . conclusions in conclusion, it is possible to design innovative multilayered surgical face masks made from biodegradable films and non-woven tissue. thus on the one hand they may reduce the likelihood of being infected with viruses and a microbiome, such as covid- , while on the other hand they may favor mouth and nose perspiration. moreover, both films and non-woven tissues [ – ] can be modified by incorporation, impregnation, coatings or grafting techniques with specific ingredients, possessing specific properties, such as bactericidal, anti-inflammatory, skin repairing and being easily degraded or recycled. on the other hand, the current commercial surgical masks, being made of different polymeric materials, are not recycled. this is the reason why many research groups are trying to develop mono-material products to be traced, selectively collected and recycled. additionally, it is also possible to make beauty masks, realized by non-woven tissues made by natural fibers and activated by ingredients for hydrating, antiaging, whitening and other cosmetic activities. these new and smart beauty masks, processed and distributed in the dry state, and activated by water, only when used, may be considered innovative and safe because they are free of preservatives, emulsifiers, colors, fragrances and other chemicals [ , , , – , ]. the active ingredients, in fact, are directly linked to the tissue’s fibers, during the producing process [ , , , – , ]. it is also important to underline that all the carriers (tissues and films) and the ingredients proposed are of a natural origin, totally biodegradable, skin and environment friendly. moreover, according to the last consumers’ requests and the normal cosmetic principles, these sustainable, genderless and smart beauty masks, focused on natural-derived ingredients and innovative technologies, could be characterized to have more effectiveness against pollution, blue-light and skin aging. in conclusion, according to the circular-green economy principles and in line with current scientific knowledge, both the surgical and beauty face masks could be made by ingredients obtained from renewable and biodegradable materials, thus contributing to reducing the pollutive worldwide waste and maintaining natural raw materials and the planet’ biodiversity for future generations. author contributions: conceptualization, p.m. and m.b.c.; investigation and data curation, g.m., v.e.y and p.m.; writing—original draft preparation, p.m.; writing—review and editing, m.b.c.; supervision, v.e.y. all authors have read and agreed to the published version of the manuscript. funding: this research received no external funding. conflicts of interest: the authors declare no conflict of interest. references . baka, a.; cenciarelli, o.; duffell, e.; melidou, a.; pettinen, p.; plachous, d. using face masks in the community. european centre od disease prevention and control; european centre for disease prevention and figure . nanocomposite structure organization made by chitosan fibers (green) and chitin nanofibrils (blue) [ ]. all the data shown by the reported research studies both in vitro and in vivo [ , , – ] could explain, therefore, part of the mechanism of the action cn and cn–lg may have on skin, when linked to the fibers’ tissue, made by biopolysaccharide polymers. according to the active ingredients linked to cn and the relative obtained complexes, the tissue may have high regenerative effectiveness on aged skin [ , , – ] or a faster repairing activity on wounded or burned skin [ , , , – ]. additionally as previously reported, we underline the possibility to realize cn films made by short fibers, which, being strictly compressed each to others, are able to filter and stop the entry of microorganisms. on the other hand, the cn-non-woven tissues, made by longer fibers connected to each other with a morphology characterized by many holes, may facilitate the interchanging of oxygen and carbon dioxide with the cells. . conclusions in conclusion, it is possible to design innovative multilayered surgical face masks made from biodegradable films and non-woven tissue. thus on the one hand they may reduce the likelihood of being infected with viruses and a microbiome, such as covid- , while on the other hand they may favor mouth and nose perspiration. moreover, both films and non-woven tissues [ – ] can be modified by incorporation, impregnation, coatings or grafting techniques with specific ingredients, possessing specific properties, such as bactericidal, anti-inflammatory, skin repairing and being easily degraded or recycled. on the other hand, the current commercial surgical masks, being made of different polymeric materials, are not recycled. this is the reason why many research groups are trying to develop mono-material products to be traced, selectively collected and recycled. additionally, it is also possible to make beauty masks, realized by non-woven tissues made by natural fibers and activated by ingredients for hydrating, antiaging, whitening and other cosmetic activities. these new and smart beauty masks, processed and distributed in the dry state, and activated by water, only when used, may be considered innovative and safe because they are free of preservatives, emulsifiers, colors, fragrances and other chemicals [ , , , – , ]. the active ingredients, in fact, are directly linked to the tissue’s fibers, during the producing process [ , , , – , ]. it is also important to underline that all the carriers (tissues and films) and the ingredients proposed are of a natural origin, totally biodegradable, skin and environment friendly. moreover, according to the last consumers’ requests and the normal cosmetic principles, these sustainable, genderless and smart beauty masks, focused on natural-derived ingredients and innovative technologies, could be characterized to have more effectiveness against pollution, blue-light and skin aging. in conclusion, according to the circular-green economy principles and in line with current scientific knowledge, both the surgical and beauty face masks could be made by ingredients obtained from renewable and biodegradable materials, thus contributing to reducing the pollutive worldwide waste and maintaining natural raw materials and the planet’ biodiversity for future generations. cosmetics , , of author contributions: conceptualization, p.m. and m.-b.c.; investigation and data curation, g.m., v.e.y. and p.m.; writing—original draft preparation, p.m.; writing—review and editing, m.-b.c.; supervision, v.e.y. all authors have read and agreed to the published version of the manuscript. funding: this research received no external funding. conflicts of interest: the authors declare no conflict of interest. references . baka, a.; cenciarelli, o.; duffell, e.; melidou, a.; pettinen, p.; plachous, d. using face masks in the community. european centre od disease prevention and control. european centre for disease prevention and control (ecdc) technical report. april . available online: https://www.ecdc.europa.eu/en/publications-data/ using-face-masks-community-reducing-covid- -transmission (accessed on august ). . nilforoushzadeh, m.a.; amirkhani, m.a.; zarrintaj, p.; moghaddam, a.s.; mehrabi, t.; alavi, s. skin care and rejuvenation by cosmeceutical facial mask. j. cosmet. derm. , , – . 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Çiçek, s. murat medicine anadolu kardiyoloji dergisi : akd = the anatolian journal of cardiology pdf view excerpt, cites background save alert research feed shared genetic architecture in the relationship between adult stature and subclinical coronary artery atherosclerosis. a. cassidy-bushrow, l. bielak, p. sheedy, s. turner, j. s. chu, p. peyser medicine atherosclerosis highly influenced view excerpts, cites background save alert research feed how height is related to our health and longevity t. samaras medicine nutrition and health pdf save alert research feed international evaluation of research and doctoral training at the university of helsinki - : rc-specific evaluation of pure - public health and epidemiology research community s. saari, a. moilanen political science pdf save alert research feed commentary. human growth, height, size reasons to be small t. samaras medicine pdf save alert research feed references showing - of references sort byrelevance most influenced papers recency short stature is associated with coronary heart disease: a systematic review of the literature and a meta-analysis. t. paajanen, n. oksala, p. kuukasjärvi, p. karhunen medicine european heart journal pdf save alert research feed is short height really a risk factor for coronary heart disease and stroke mortality? a review. t. samaras, h. elrick, l. storms medicine medical science monitor : international medical journal of experimental and clinical research pdf save alert research feed young candidates for coronary heart disease. m. gertler, s. garn, p. white medicine journal of the american medical association save alert research feed the fetal and infant origins of disease d. barker medicine european journal of clinical investigation save alert research feed short stature and coronary heart disease: a ‐year follow‐up of the finnish cohorts of the seven countries study t. forsén, j. eriksson, q. qiao, m. tervahauta, a. nissinen, j. tuomilehto medicine journal of internal medicine save alert research feed explaining the sex difference in coronary heart disease mortality among patients with type diabetes mellitus: a meta-analysis. a. kanaya, d. grady, e. barrett-connor medicine archives of internal medicine pdf save alert research feed relation of adult height to cause-specific and total mortality: a prospective follow-up study of , middle-aged men and women in finland. p. jousilahti, j. tuomilehto, e. vartiainen, j. eriksson, p. puska medicine american journal of epidemiology pdf save alert research feed role of known risk factors in explaining the difference in the risk of coronary heart disease between eastern and southwestern finland. p. jousilahti, e. vartiainen, j. tuomilehto, j. pekkanen, p. puska medicine annals of medicine save alert research feed changes in premature deaths in finland: successful long-term prevention of cardiovascular diseases. p. puska, e. vartiainen, j. tuomilehto, v. salomaa, a. nissinen medicine bulletin of the world health organization pdf save alert research feed evaluating the impact of population and high-risk strategies for the primary prevention of cardiovascular disease. j. emberson, p. whincup, r. morris, m. walker, s. ebrahim medicine european heart journal pdf save alert research feed ... ... related papers abstract tables and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); 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bdivision of medical biotechnology, paul ehrlich institute, langen, germany abstract sleeping beauty (sb) is the first synthetic dna transposon that was shown to be active in a wide variety of species. here, we review studies from the last two decades addressing both basic biol- ogy and applications of this transposon. we discuss how host–transposon interaction modulates transposition at different steps of the transposition reaction. we also discuss how the transposon was translated for gene delivery and gene discovery purposes. we critically review the system in clinical, pre-clinical and non-clinical settings as a non-viral gene delivery tool in comparison with viral technologies. we also discuss emerging sb-based hybrid vectors aimed at combining the attractive safety features of the transposon with effective viral delivery. the success of the sb- based technology can be fundamentally attributed to being able to insert fairly randomly into genomic regions that allow stable long-term expression of the delivered transgene cassette. sb has emerged as an efficient and economical toolkit for safe and efficient gene delivery for med- ical applications. article history received july revised september accepted september keywords sleeping beauty; host–transposon interac- tions; transposition; non- viral; gene therapy; transgenesis; oncogenomics introduction transposable elements (tes) are repetitive sequences that are components of nearly all genomes (huang et al., ). approximately % of the human genome is derived from tes (cordaux & batzer, ; lander et al., ). the vast majority of tes accumulate inacti- vating mutations over evolutionary time to give rise to a fraction of the genome that is often called “junk dna”. recent studies suggest that the portion of the inactive mass is going through a recycling, “gain of function” process, yet to be fully deciphered (lander et al., ; prak & kazazian, ). in an attempt to turn the “junk” into a “jewel”, a reverse engineering approach was applied to eliminate the accumulated mutations of tc - family transposons in fish genomes, which resulted in a synthetic transposon system known as sleeping beauty (sb) (ivics et al., ). sb not only represents the first dna-based te ever shown to be active in vertebrates, but the first functional gene ever reconstructed from an inactive, ancient genetic material, for which an active, naturally occurring copy either does not exist or has not yet been isolated. currently, the hyperactive version of sb (sb x) is one of the most active transposon in ver- tebrates (mates et al., ). sb gave an opportunity to understand several aspects of transposon regulation. it is assumed that, unlike viruses, tes and the host have coevolved in a way that permits propagation of the transposon, but minimizes damage to the host. the sb system is an excellent tool to model horizontal gene transfer or the establishment of a complex interaction network between a vertebrate host and a transposon. the accumulated knowledge of transposon biology was also applied to establish a transposon-based tech- nology platform for genome engineering in vertebrate species, including cancer research, gene annotation, ver- tebrate transgenesis or gene therapy (ivics et al., ). the sleeping beauty transposon sb belongs to the tc /mariner superfamily of dna transposons (plasterk et al., ) comprising a trans- posase gene flanked by inverted repeats (irs) contain- ing recognition sequences for transposase binding (figure a). transposases of the tc /mariner superfamily, the bacterial insertion sequence (is) elements, retroviral integrases and the v(d)j recombinase contain an evolu- tionarily and functionally conserved catalytic domain, having a dde/d (asp, asp, glu) motif. dde/d contact dr. zsuzsanna izsv�ak zizsvak@mdc-berlin.de max delbr€uck center for molecular medicine in the helmholtz association (mdc), robert r€ossle str. , berlin, germany � max delbr€uck center for molecular medicine. this is an open access article distributed under the terms of the creative commons attribution-noncommercial-noderivatives license (http://creativecommons.org/licenses/by- nc-nd/ . /), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way. critical reviews in biochemistry and molecular biology, vol. , no. , – http://dx.doi.org/ . / . . http://creativecommons.org/licenses/by-nc-nd/ . / http://creativecommons.org/licenses/by-nc-nd/ . / recombinases catalyze a remarkably similar overall chemistry of dna recombination (craig, ; ivics & izsvak, ). each ir unit of these elements is – bp in length, and possesses two transposase binding sites known as direct repeats (drs) that are – bp in length. the left ir is not identical to the right ir, as the former contains an extra “half direct repeat (hdr)” of the transposase-binding site acting as a transpositional enhancer (izsvak et al., ) and the untranslated regions (utr) regions which appear to regulate transposition transcriptionally (moldt et al., ; walisko et al., ) (figure a). mechanism of sleeping beauty transposition during non-replicative, “cut and paste” transposition of sb, the transposase first binds to its recognition sequences (drs) of the transposon (figure ). during synaptic complex formation, the two transposon ends are brought together. the transposon is liberated by excision, and the excised molecule is mobilized between the donor and the reintegration loci. the transposase acts at least as a tetramer (izsvak et al., ). excision leaves a footprint ( bp) at the donor site while integration results in target site duplications (ivics et al., ) (figure ). structure of the sleeping beauty transposase the sb transposase contains an n-terminal dna-binding domain (dbd), a nuclear-localizing signal (nls) involved in nuclear transport and a c-terminal catalytic domain (dde) involved in the dna cleavage and strand transfer reactions (ivics et al., )(figure b). the bipartite dbd consists of two subdomains; namely, the pai and red (pai þ red ¼ paired; connected by a linker), and shows similarity to the paired domain of the pax tran- scription factor family (czerny et al., ). both the pai and red subdomains are predicted to possess three alpha helices, two of which form a helix-turn-helix (hth), found in many dna-binding proteins (aravind et al., ). similarly to other dde recombinases, the catalytic domain is predicted to have an rnaseh-like fold (hickman et al., ; rice & baker, ). despite multiple attempts over the last decade, the crystal structure of the full-length sb transposase remains unknown. alternatively, successful studies have been reported on solving the structure of functional domains separately (carpentier et al., ; voigt et al., ) (figure ). the closest structure to sb is mos (richardson et al., ). mos is a mariner-family trans- posase that, similarly to sb, belongs to the tc /mariner superfamily. the dna-binding domain the nmr structure of the pai domain confirms previous predictions (izsvak et al., ), in that it possesses three alpha helices (helix ¼ – ; helix - ¼ – ; helix ¼ – ) (carpentier et al., ) (figure b, figure a). although the structure of a pai domain/dna substrate complex is currently unknown, the residues involved in dna binding were identified to be in the second alpha helix, connecting hth loop and the third alpha helix (residues , , , – , – , ) (figure b, figure a). the pai domain binds to the dr-core sequence located within the inner and outer drs. upon comparison of sb-pai domain with other dbds of the related tc /mariner family members (e.g. tc and mos ), the figure . structure of the sleeping beauty transposon system. (a) the sleeping beauty (sb) system. the transposase gene (yellow rectangle) is flanked by left and right inverted repeats (irs) (arrows). each ir contains two direct repeats (dr), an inner (dri; orange) and an outer (dro; brown) to which the transposase (yellow pie) binds at the respective core regions (gray thick line). (b) domain organization of the transposase: the transposase consists of an n-terminal, dna-binding domain (pai þ red), a nuclear localization signal (nls), an interdomain linker and a c-terminal, catalytic domain (cd). the cd has a clamp loop with a glycine strip (ggg) and three conserved catalytic residues (dde). both pai and red domains contain three alpha-helices and are separated from each other by a grrr at-hook motif. numbers in the lowest panel repre- sent residues that directly interact with the dna. a color ver- sion of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). critical reviews in biochemistry and molecular biology http://www.informahealthcare.com/bmg main differences are observed in the length and rela- tive orientations of the alpha helices. as pax has the highest amino acid sequence similarity to the sb-pai than tc or mos , we superimposed pax and sb-pai structures (figure b). the pai domain of sb differs from pax with respect to helix- in spite of high similarity at sequence level, and this could be attributed to the simple fact that the structure of sb’s pai was obtained without dna whereas the structure of pax was deciphered in-complex with dna (figure b). the catalytic domain the structure of the sb transposase catalytic domain along with the flexible inter-domain linker was recently crystalized and used to model the sb transposase/trans- poson complex (voigt et al., ). as expected (rice & baker, ), the catalytic domain of the sb transposase contains a canonical rnaseh-fold, consisting of centrally located b-sheets (five-stranded) surrounded by a-helices (five) (figure c). the catalytic residues (d , d and e ) are assembled in close proximity establishing figure . host factors assist sleeping beauty transposition. schematic representation of transposon mobilization: following expres- sion ( ) sb (red spheres) binds to the irs ( ) leading to the formation of a synaptic complex ( i) resulting in excision ( ii) from the donor dna. the excised element then inserts into a ta dinucleotide (�) ( iii), which is duplicated following a successful inte- gration. excision would leave a -bp footprint behind. role of host factors in regulating transposition: transcriptional control: the high mobility group protein, hmgxb upregulates sb transcription (green arrow). upon expression, the sb transposase antagonizes the effect of hmgxb . the synaptic complex: sb recruits the high mobility group protein, hmgb (green ovals), which promotes synaptic complex assembly starting at the inner drs. prevention of autointegration: the host factor, barrier-to- autointegration factor (baf ) prevents suicidal self-integration. excision site repair: the ku / complex of the non-homologous end joining repair pathway (nhej) assists healing double stranded dna damage generated upon transposon excision. cell cycle modulation: sb modulates cell cycle transition via miz by down regulating cyclin d expression. a color version of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). s. a. narayanavari et al. http://www.informahealthcare.com/bmg an active site conformation, similarly to the one observed in the crystal structure of the mos transpo- sase (richardson et al., ). in addition, the catalytic domain also contains a flexible “clamp loop” having a glycine-rich strip (ptvkhggg; with three consecutive glycine residues), which is inserted within the rnaseh- fold (figure b, figure c). the sb-rnaseh superim- poses closely (rmsd of . Å) with mos , except in the linker and the clamp loop domains (figure d). the clamp loop assumes an unusually bent conformation (at three consecutive glycine residues) that is predicted to form a protein–protein interface between protein monomers (figure e). as in mos (richardson et al., ), this interface might bring two catalytic domains into close proximity with their active sites facing each other during synaptic assembly. the clamp loops of both protomers form reciprocal interactions with the rnaseh core of the partner molecule (figure e). the clamp loop also contains two short anti-parallel b-strands, forming a b-hairpin that interacts with the main chain of the interdomain linker of the partner mol- ecule (figure e). due to the lack of the availability of a co-crystal containing the substrate dna with transpo- sase, the authors generated an in silico transposon cap- ture complex (tcc) model. the tcc model contains the full-length transposase complexed with target dna. in the proposed model, the positively charged groove of the catalytic domain can accommodate the bent figure . structure of the sleeping beauty transposase. (a) structure of the pai domain as deciphered by nmr. the structure con- sists of three a helices (in orange; pdb m e). amino acids involved in dna binding are highlighted in gray. (b) superimposition of pax (in green; pdb k ) with the pai domain. the differences are highlighted by a dotted circle. (c) structure of the cata- lytic domain (cd; in orange; pdb cr ) showing the n-terminal interdomain linker in gray, a helices in orange, b sheets in purple. the glycine strip (shown in cyan) is part of the clamp loop. the three catalytic residues, dde are shown in gray. (d) superimposition of the catalytic domain (cd) of sb (red) on mos structure (cyan; pdb hos). note that main differences among them are located in the clamp loop (circled dotted line). (e) the potential role of the clamp loops in sb dimerization. (f) the mutation (i s) further improves the hyperactivity of sb x (voigt et al., ). the davq stretch is used as a reference to show the position of i- (refer the adjoining inlet). the structural analysis was done by the chimera version of . . (pettersen et al., ). a color version of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). critical reviews in biochemistry and molecular biology http://www.informahealthcare.com/bmg target dna. the model is in conjunction with earlier studies showing that sb prefers bendable, even severely distorted target sites (vigdal et al., ). using the tcc model, it was also possible to rationalize previous hyperactive mutations (sb x), and also design novel hyperactive variants (voigt et al., ). the structure- based engineering might pave the way for the future development of designer transposases with differential activities and target site specificities. transposon–host interactions sb is a synthetic transposon, mimicking an ancestral element that was highly successful in the genomes of various fish species > million years ago (ivics et al., ). inactive sb-like elements are widespread in vari- ous fish species, are also present in certain amphibian species but never colonized other vertebrates (ivics et al., ). thus, no sb-like sequences are present in mammals, including humans. in fact, the human gen- ome consists of around % inactivated dna transpo- sons (cordaux & batzer, ; lander et al., ). the most closely related sequences to sb are the human mariner elements, belonging to the same tc /mariner superfamily of transposons. while no active dna trans- poson is present in the human genome, certain copies have been “recycled” in a domestication process, and gained a novel cellular function. for example, specific mariner loci gave rise to microrna (mirna) genes (borchert et al., ; smalheiser & torvik, ), and five piggybac-derived elements (pgbd – ) are under selection presumably to perform novel, yet to be char- acterized cellular activities. importantly, the sb transpo- sase is highly specific with respect to the sequences that it can mobilize, and does not cross-mobilize related tdr elements in the zebrafish genome (ivics et al., ; izsvak & ivics, ). surprisingly, by contrast, pgbd has been reported to be capable of mobilizing the insect-derived gene transfer tool, piggybac (henssen et al., ; ivics, ). despite being resident only in fish, the transpos- ition reaction catalyzed by sb is supported in all chordata species tested (izsvak et al., ), including the non-vertebrate ciona intestinalis (hozumi et al., ). the only report where sb was shown to suc- cessfully transpose outside chordates was an inverte- brate, the black legged tick (ixodes scapularis, phylum arthropoda) (kurtti et al., ). remarkably, the insect i. scapularis seems to be able to cross the chordata-specific barrier as an animal/human patho- gen (e.g. lyme disease). compared to sb, piggybac, originating from an insect (trichoplusia ni) (lobo et al., ) has a relatively loose host requirement, because it can transpose even in human cells. in contrast, the p element has an extreme species-specificity, and it is active only in a single species (drosophila mela- nogaster). previously, it was generally accepted that a transposon capable of transposing in vitro does not require host-encoded factors. furthermore, transpo- sons with wide host range were assumed to require no host factors (raz et al., ; vos et al., ). both assumptions are proved to be false. first, although the nematode tc is capable of performing transposition in vitro, it is not able to support precise transposition in a phylogenetically distant host (schouten et al., ; vos et al., ). second, the vertebrate-specific sb transposition requires a number of host factors, but these host-encoded proteins are evolutionary conserved in vertebrates. the strategy of recruiting phylogenetically conserved cellular factors could help to establish a stable host–transposon rela- tionship upon colonizing a related naïve genome. a delicate host–transposon relationship is import- ant for stabilizing long-term transposon–host coexist- ence. via its host factors, sb is able to sense and react to various signaling processes, and participates in complex interactive regulatory processes involving evolutionary conserved cellular mechanisms (figure ). host-encoded factors might enable the transposon to sense and react to spatio-temporal cellular signals and help to filter out aberrant transposition products (wang et al., c). the transposition reaction might not work at all or would lose fidelity under condi- tions, where host factors are not accessible. indeed, when a transposon is transferred too far from its ori- ginal host, the conditions in a new environment could be suboptimal, and the fidelity of the reaction could be compromised. for example, the nematode tc catalyzed aberrant transposition reactions in zebrafish (raz et al., ). another example is the piggybac that in comparison to sb performs more fre- quent, aberrant transposition products in mammalian cells (wang et al., c). understanding the delicate mechanisms of transposon–host coexistence can help us to design gene transfer tools with minimal geno- toxicity. the accessibility of a host factor in a given cell type is likely to affect the efficacy of the reaction. indeed, it has been observed that the frequency of sb transposition varies in different vertebrate cells (copeland & jenkins, ; dupuy et al., ; dupuy et al., ; fischer et al., ; horie et al., ; luo et al., ; yant et al., ; yusa et al., ). the host-encoded factors of sb transposition represent a variety of cellular processes, and are involved at vari- ous steps of the reaction (figure ). s. a. narayanavari et al. transcriptional regulation by hmgxb a component of the wnt signaling pathway (yamada et al., ), hmgxb (also known as hmg l ), func- tions as a transcription factor of sb transposase expres- sion (walisko et al., ). hmgxb accesses the ’-utr region of the transposase coding sequence, and pro- motes its transcription. besides acting as a transcription factor, hmgxb is able to physically associate with the transposase protein. sequestering hmgxb not only abolishes hmgxb -mediated transcriptional activation, but has a repressing effect on transcription by the - utr (walisko et al., ). thus, sb transposase can exert a negative feedback regulation on its own expres- sion with the transposase/hmgxb complex acting as a transcriptional repressor (figure ). dna methylation enhances sleeping beauty transposon excision dna methylation plays an important role in regulating the activity of tes. dna methylation triggers the forma- tion of heterochromatin, and is associated with tran- scriptional repression. curiously, sb excision is significantly (� x) enhanced upon cpg methylation of the sb transposon (yusa et al., ). similar enhancement was also observed with other members of the ir/dr subfamily of transposases, including frog prince, and minos elements (jursch et al., ), but not with simple-ir transposons. according to a model, cpg methylation and subsequent chromatin condensation promotes synaptic complex formation. the chromatin condensation helps to bring the distantly located recog- nition sequences (drs) of the ir/dr structure into a close proximity, and results in enhanced transposon excision (jursch et al., ). this feature might help the sb transposon to escape cpg methylation-based epi- genetic repression. importantly, although sb excision might be enhanced by a condensed chromatin struc- ture, transposon integrations are not enriched in het- erochromatic regions (gogol-doring et al., ; huang et al., ). hmgb assists pre-cleavage complex formation another high-mobility group protein, hmgb , a highly conserved dna bending protein was identified as a cofactor of sb transposition (zayed et al., ). it has been postulated that hmgb might induce conform- ational changes in the transposon dna, promoting effi- cient synaptic complex formation. hmgb stimulates preferential binding of the transposase to the inner drs, located distantly from the cleavage site, indicating that hmgb might be involved in a regulatory check- point to enforce synapsis prior catalysis. it is interesting to note that, hmgb has also been shown to be assist- ing in v(d)j recombination process, by its dna bending activity during paired end complex formation (van gent et al., ) (figure ). assistance from the host dna repair to seal sleeping beauty inflicted dna damage in contrast to bacterial dde/d transposition or v(d)j recombination, members of the tc /mariner superfam- ily, including sb, do not use a hairpin intermediate to liberate the transposon (izsvak et al., ; richardson et al., ). the sb transposase cleaves both strands of the dna, thereby leaving a double strand break (dsb) at the excision site (izsvak et al., ), while transposon integration is assumed to generate single stranded gaps. the transposase is not able to seal the gap alone, and recruits ku , along with the dna-dependent pro- tein kinase (dna-pkcs), the key factors of the non-hom- ologous end joining (nhej) pathway of dsb repair to repair the excision sites (izsvak et al., ; yant & kay, ) (figure ). dna-pkcs is a limiting factor of sb transposition, as its cellular level affects the frequency of the reaction. potential host-encoded factors involved at the integration site repair are yet to be identified. however, the dependence of sb transposition on nhej to seal the gaps is not absolute, nhej and hr both con- tribute to the repair of sb-induced dsbs in mammalian somatic cells (figure ). modulation of the cell cycle myc-interacting protein zinc finger (miz ) transcription factor was identified as an interacting partner of the sb transposase in a yeast two-hybrid screen (walisko et al., ). sequestration of miz results in a down-regula- tion of cyclin d expression, which eventually leads to a temporary cell cycle arrest in g by interfering with the g /s transition (figure ). curiously, a temporary g arrest enhances transposition suggesting that sb trans- position might be favored in the g phase of the cell cycle where the nhej pathway of dna repair is prefer- entially active (walisko et al., ) (figure ). the sb transposase-induced g slowdown by interfering with cell cycle represents a common strategy shared by selfish genetic elements (walisko & ivics, ). stable overexpression of sb has also been reported to induce a g /m arrest and apoptosis (galla et al., ). importantly, the apoptosis is not associated with trans- posase-induced dna damage, but most probably a critical reviews in biochemistry and molecular biology response to accumulated transposase proteins in the nucleus due to overexpression. protection from a self-destructive autointegration process during the excision process of transposition, the excised transposon could be re-inserted into its own genome in a self-disruptive process, known as suicidal autointegra- tion. this phenomenon has been widely associated with various retroviruses, but is also observed to affect trans- position, including sb (benjamin & kleckner, ; garfinkel et al., ; maxwell et al., ; shoemaker et al., ; wang et al., b). intriguingly, barrier-to- autointegration factor (banf also known as baf ), a cellular co-factor of certain retroviruses was detected in higher-order protein complexes containing the sb transposase. thus, similarly to certain viruses the sb transposon/transposase is able to recruit the phylogen- etically conserved cellular protein banf to avoid sui- cidal autointegration. banf is presumably acting by compacting the excised, extracellular transposon gen- ome to be a less accessible target for autointegration, thereby promoting productive chromosomal integration (wang et al., b) (figure ). integration site distribution sequence analysis of sb integration sites from mamma- lian cells showed that integration occurs exclusively into ta dinucleotides (ivics et al., ) (figure ). target site selection of sb is rather structure- than sequence-specific, and at-rich palindromes around the central ta nucleotide help to form a preferred bendable dna structure (vigdal et al., ). while remobilization of the sb transposon from a genomic locus exhibits the “local hopping” phenom- enon, resulting in de novo integrations in the neighborhood of the donor site within few megabase window (keng et al., ; kokubu et al., ; luo et al., ; yant et al., ). in contrast, the integration profile is fairly random with a small bias toward certain repetitive elements when initiated from an ectopic mol- ecule. it was observed that sb targets microsatellite dna, mir-type sines (short interspersed elements) more frequently, while avoids long terminal repeat (ltr) elements and line- repeats (yant et al., ). the close-to-random integration profile of sb has no overt bias for integrating into genes or near transcrip- tional regulatory regions of genes (gogol-doring et al., ; yant et al., ). thus, sb integrations display only a minor enrichment near transcription start sites (tsss) or near transcription-associated histone modifica- tions, including mono-methylated h k (a marker for enhancer regions) and tri-methylated h k (associated with promoters of active genes). integration is not favored either in regions rich in h k me (a histone modification typically associated with transcriptionally repressed heterochromatin) (gogol-doring et al., ; huang et al., ). this close-to-random integration profile of sb was confirmed by multiple studies, and was reported from various organisms and cell types (ammar et al., a; geurts et al., ; gogol-doring et al., ; huang et al., ; liu et al., ; moldt et al., ; vigdal et al., ; voigt et al., ; yant et al., ). nevertheless, the fairly random integration of sb seems to be rather exceptional among transposons and inte- grating viruses in mammalian cells (figure ). the tol transposon (also of fish origin) exhibits a preferential integration into transcription start sites and transcrip- tional regulatory regions (ammar et al., a; grabundzija et al., ; huang et al., ). piggybac has also a biased insertion pattern, and has a pro- nounced preference for integrating into the -transcrip- tional regulatory regions of genes (huang et al., ; figure . integration profile of various integrating vectors. sb (red vertical lines) has a fairly random integration profile when compared to other dna transposons like piggybac (pb) (green vertical lines) and tol (black vertical lines) and viral systems like hiv (cyan vertical lines) and mlv (green vertical lines). tss: transcription start site. a color version of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). s. a. narayanavari et al. http://www.informahealthcare.com/bmg gogol-doring et al., ). curiously, the piggybac trans- poson displays an integration profile highly similar to that of the mlv retrovirus (de jong et al., ; wu et al., ), and both mlv integrase and the piggybac transposase interact physically with bet pro- teins for guided integrations to specific chromatin envi- ronments (de rijck et al., ; gogol-doring et al., ; gupta et al., ; sharma et al., a). the hiv- integrase also uses a host tethering complex ledgf/ p /psip to localize genomic targets (ciuffi et al., ), and exhibits a strong preference for actively transcribed genes (schroder et al., ). whether the close-to-ran- dom integration profile of sb is guided by a cellular fac- tor is yet to be explored. regulating transcription from sleeping beauty by rna interference numerous studies indicate that the host-encoded rna interference (rnai) mechanism regulates transposition by suppressing transposase expression (robert et al., ; sijen & plasterk, ; vastenhouw & plasterk, ; vastenhouw et al., ). in c. elegans, where tc transposition is active, three main mechanisms were proposed to generate double stranded rnas (dsrnas) that are eventually fed into rnai pathway of silencing. besides bidirectional transcription from the transposon, dsrna can also be derived from read-through transcrip- tion from neighboring genes that can form hairpin structures of dsrna (sijen & plasterk, ). alternatively, rna-directed rna polymerases can copy tc -transcripts into dsrna (sijen & plasterk, ). transposase-mediated integration avoids the formation of multiple, tandem integrations, which could trigger rnai-mediated heterochromatin formation and silenc- ing. nevertheless, bidirectional (convergent) transcrip- tion driven by the irs of sb may lead to the formation of dsrna, which can serve as templates for the rnai machinery (moldt et al., ; rauschhuber & ehrhardt, ; walisko et al., ). the distance between the irs, e.g. the size of the transposon influences the fre- quency of the dsrna production. interestingly, mariner elements frequently give rise to short internally deleted transposon variants, known as miniature inverted repeat elements (mites). certain mariner-derived mites function as regulatory mirna genes in the human gen- ome (piriyapongsa & jordan, ). overproduction inhibition is autoregulatory the efficiency of transposition reaction is limited by a phenomenon termed overproduction inhibition (opi). opi is a well-known observation among tc /mariner elements, in which the transposase appears to inhibit transposition above a certain dosage (bouuaert et al., ; grabundzija et al., ). although opi is involved in maintaining a stable co-existence between the trans- poson and its host, it is assumed to be an autoregula- tory mechanism. the current explanation behind this phenomenon lies in the observation that excess trans- posase molecules can saturate the binding sites on the irs before productive synapsis could take place, thereby poisoning the reaction (claeys bouuaert et al., ). alternatively, it is also plausible to assume that improp- erly folded and/or truncated transposase molecules inhibit transposition by competing with the active transposase molecules (reviewed in (izsvak & ivics, )). translating sleeping beauty transposition biology although sb-like transposons have been inactivated millions of years ago, the synthetic sb transposon has started a new “career” in synthetic biology. importantly, the accumulated knowledge of the mechanism of its transposition and its interaction with a vertebrate host enables us to modulate the transposition reaction for various applications (figure ). compared to viral vectors that have been engineered over decades for their use in gene therapy, the sb sys- tem was established relatively recently. since its discov- ery, it has been used in translational biology, and proved to be tremendously successful for delivery of gene cassettes for addressing a variety of questions, under various molecular contexts and for various appli- cations both in conjunction with other genetic manipu- lation tools and as a standalone entity (figure ). its success in all tested scenarios can be fundamentally attributed to its exquisite features; first, having an abil- ity to insert fairly randomly, second, being able to insert into regions that allow long-term expression of the delivered cassette and third, allowing low cost vector production. the two-component transposon vector system the basis of using sb as a tool was establishing a two- component transposon system. as the sb transposase recognizes the irs in trans, it was possible to physically separate the transposase coding sequence from the rec- ognition motifs for the transposase (drs). this gene transfer system is suitable to mobilize a gene of interest (transgene) flanked by the irs. the two-component sys- tem can be placed on various carriers, such as plasmid dna (non-viral vector) or can be combined with various critical reviews in biochemistry and molecular biology viruses (hybrid transposon/virus vectors). the transpo- sase can be also supplied in the form of an mrna. it is widely believed that naturally occurring transpo- sons have not been selected for the highest possible activity, and are strongly down regulated. since trans- posons co-exist with their hosts, transposition activity is regulated in order to avoid insertional inactivation of essential genes. low intrinsic activity, self-regulation and interaction with cellular host factors appear to allow wild type transposons to persist in the host with- out producing serious levels of genetic damage. to derive an optimal molecular tool, it was necessary to optimize both components of the sb system. optimization efforts generated several hyperactive variants of the sb transposase (baus et al., ; geurts et al., ; mates et al., ; voigt et al., ; yant et al., ; zayed et al., ) (figure ). molecular evolution was used to generate the hyper- active sb x (mates et al., ) (figure ). sb x is now a component of the first plasmid-based vector sys- tem that is able to overcome the efficacy problem of non-viral vectors, and can transfer genes at an efficiency comparable to integrating viral systems even in stem and progenitors cells (mates et al., ). sb x carries a combination of nine amino acid substitutions, scat- tered along the coding sequence of the transposase (figure ). curiously, the individually hyperactive single amino acid changes cannot be freely combined, and only a fraction of hyperactive mutations are compatible with each other (“friendly” mutations). in principle, figure . sleeping beauty transposon-based applications. sb was successfully used for germline transgenesis, in various models (fish , frog , rat , mouse , rabbit , pig , cow and sea squirt ). the sb system has been employed for somatic gene delivery in various vertebrates, but also in a tick (insect) cell line, ise . sb-based gene delivery has been used in several preclinical animal models. alternatively, the mutagenic version of the sb can be employed in functional genomics. insertional mutagenesis screens can be used to annotate genes in somatic cells (oncogenomics) or in the germline. abbreviations: enos: endothelial nitric oxide synthase; hugt a : human uridinediphosphoglucuronate glucuronosyltransferase- a ; statin-ae: angiostatin–endostatin fusion cassette; dmd: duchenne muscular dystrophy; dysf: dysferlin; idua: a-l-iduronidase; fah: fumarylacetoacetate hydrolase; ins: insulin; l/vdlrs: low-density lipoprotein and very-low-density lipoprotein receptors; mir– : micro rna ; iod: indoleamine- , dioxygenase; dsred : red fluorescent protein ; gfps: green fluorescent proteins; simstn: sirna against myostatin; sihtt: sirna against huntington; lamb : laminin subunit beta- ; hsvtk: herpes simplex virus thymidine kinase type gene; bcp-all: b cell precursor acute lymphoblastic leukemia). a color version of the figure is available online (see color version of this figure at www. informahealthcare.com/bmg). s. a. narayanavari et al. http://www.informahealthcare.com/bmg http://www.informahealthcare.com/bmg hyperactivity might interfere with the fidelity of the transposition reaction, and generate more frequent aberrant transposition products, as it was recently shown for certain mariner elements (bouuaert et al., ; liu & chalmers, ). importantly, despite its hyperactive nature, sb x catalyzes a faithfully precise transposition reaction. in most of its features, sb x does not significantly differ from first-generation sb transposase, including its stability, opi profile and affin- ity to the transposon irs. in contrast, sb x is less sen- sitive to heat shock-induced aggregation, suggesting that the hyperactive mutagenesis affected the folding of the transposase in a positive way (mates et al., ). perhaps the hyperactivity of sb x could be further improved. indeed, the recently solved crystal structure of the catalytic domain of the transposase could be a useful resource of structure-based engineering of tail- ored sb transposases (voigt et al., ). the transposon dna sequences have also undergone stepwise optimization. first, a minimal vector was con- structed, where the regulatory sequences, including promoter/enhancer was removed from the transposon (cui et al., ). this step created a transcriptionally neutral vector. second, transposon excision was improved by correcting/optimizing the recognition sequences (ir/dr) of the minimal vector (cui et al., ; izsvak et al., ). third, the neighboring sequence of the irs was changed to mimic a natural tar- get site of sb (cui et al., ). this minimal sb system is highly flexible and can be combined with many add- itional features. the basic rule is that the irs should flank the cargo. the cargo can be a single or multiple expression cassettes (kowarz et al., ). an advanta- geous feature of sb, compared to retroviral vectors, is that it does not require reverse transcription, thus it is able to express transgenes of highly complex structure (e.g. repeated motifs, multiple genes, various regulatory sequences, etc.). sb-mediated integration supports highly efficient transgene integration in various cell types (izsvak et al., ). the list includes somatic or germ cells, differenti- ated or stem cells essentially in all vertebrate species (figure ). sb is suitable for genetic modification of both overexpressing and knocking down (hu et al., ) transgene expression, and can be combined with other recombination techniques (grabundzija et al., ) or delivery approaches (non-viral/viral). indeed, in the last decade a whole technology platform, a figure . multiple sequence alignment of sleeping beauty transposase sequences. hyperactive amino acid mutations (in white and/or gray) compared to sb the original version of the sb transposase, sb . hyperactive sb and sb x are targeted for clinical applications. multiple sequence alignment was performed using ebi clustal omega (sievers et al., ) and shading was performed using boxshade server version . (http://www.ch.embnet.org/software/box_form.html). critical reviews in biochemistry and molecular biology http://www.ch.embnet.org/software/box_form.html “transposon toolbox”, has been established around sb (for review see (ammar et al., b)). sb can be opti- mized for stable transgene expression (gene/cell ther- apy, germ line transgenesis). alternatively, the vector can be developed as a highly potent mutagenic agent for gene annotation (somatic/germ line mutagenesis) (figure ). sleeping beauty for biotechnology the sb system has been extensively applied in routine cell culture (for creating transgenic cell lines and for gene knockdowns). this plasmid-based system can be combined with any conventional non-viral delivery technique (e.g. electroporation, essentially all commer- cially available transfection reagents, etc.). sustainable long-term expression of transgenes remains a significant challenge for large-scale biotech- nological applications, especially when antibiotic selec- tion is not applicable. for such a purpose, sb represents an attractive transgene expression vector because of its ability to promote efficient genomic integration in a variety of mammalian cell types. transposons, including sb, piggybac and tol are suitable for generating poly- clonal cell pools or clonal cell lines for large scale (industrial) production of recombinant proteins in chinese hamster ovary (cho) cells (balasubramanian et al., ). the characterized expression cassette can be exchanged relatively simply when the sb cassette is combined with other molecular engineering tools (grabundzija et al., ; petrakis et al., ). a power- ful strategy could be used to express a series of expres- sion cassettes from the same genomic locus by cassette exchange using cre or flp recombinases (garrels et al., a; grabundzija et al., ). recently, a protein-based sensor system was also developed and delivered using sb system for pharma- cokinetic and pharmacodynamics characterization of various synthetic analogs of vitamin d (staunstrup et al., ). sleeping beauty to generate induced pluripotent stem cells reprogramming of somatic cells provides an oppor- tunity to generate patient/disease-specific pluripotent stem cells that can be genetically modified, expanded and differentiated into multiple cell types for gene therapy applications. although retroviral and lentiviral vector systems have been used for generation of induced pluripotent stem cells (ipscs), they are associ- ated with increased prevalence of tumor formation (okita et al., ). attempts have been made to gen- erate ips cells using non-viral approaches such as transposon-based systems (grabundzija et al., ; kaji et al., ; muenthaisong et al., ; woltjen et al., ; yusa et al., ). the sb system is sim- ple, economical and convenient. the reprogramming efficiency is similarly effective compared to viral vec- tors (grabundzija et al., ). indeed, the sb system has been successfully used for the production of ipscs in various organisms and models (davis et al., ; fatima et al., ; grabundzija et al., ; kues et al., ; muenthaisong et al., ; talluri et al., ). after generating ipscs, the expression of reprog- ramming factors needs to be modulated or shut down for further differentiation or genetic modifica- tions. for personalized gene or cell therapy, the patient-derived ipscs need to be genetically modified with the therapeutic gene of interest followed by dif- ferentiation into a specific lineage and transplantation of these corrected cells back to the patients. to achieve these goals, sb transposon was engineered to carry both reprogramming cassette and recognition motifs for the cre recombinase (grabundzija et al., ). after successful reprogramming, the reprogram- ming cassette could be either excised or exchanged with a therapeutic gene construct. this strategy would allow reprogramming and phenotype correc- tion in a single step. overall, the sb system repre- sents a non-viral methodology for the generation of therapeutically safe pluripotent stem cells. enriching for human naïve-like pluripotent stem cell populations the ability to derive and stably maintain ground-state human pluripotent stem cells (hpscs) that resemble the cells found in vivo in the inner cell mass has the poten- tial to be an invaluable tool for researchers developing stem cell-based therapies. considerable efforts have been made to isolate and enrich cells with ground-state pluripotency in vitro. to date, derivation of human naïve-like pluripotent stem cell lines has been limited to a small number of lineages, and their long-term cultur- ing remains problematic (for review see (izsvak et al., )). the sb system has been successfully used for genetic and phenotypic tagging, selecting and main- taining naïve-like hpscs (wang et al., a; wang et al., ). hpscs were tagged by gfp driven by the ltr of hervh endogenous retrovirus promoter. by using the reporter, homogeneous hpsc cultures can be derived, characterized and maintained long term by repeated re-sorting and re-plating steps. in this setup, s. a. narayanavari et al. sb is used to screen for transcriptionally permissive gen- omic loci in pluripotent stem cells. in addition, sb sup- ports stable expression of the ltr -gfp reporter, and enables to optimize long-term culturing. this strategy has been reproduced with multiple hpsc lines, includ- ing embryonic and induced pluripotent stem cells (wang et al., ). optimizing sleeping beauty for gene therapy the advantages of using the sb system lays in its simpli- city, unbiased integration pattern, low post-integration silencing of the transgene and its high cargo capacity. for therapeutic applications, the sb system has been further improved addressing efficacy and safety issues (for reviews (boehme et al., ; di matteo et al., ; hackett et al., ; hou et al., ; ivics & izsvak, ; ivics & izsvak, ; izsvak et al., ; singh et al., ). an optimal vector for the cargo beside sequence and conformation, sb transposition was shown to be sensitive to the size of the dna cargo between the irs (izsvak et al., ). bringing the two irs in a physical proximity (� bp) enhances trans- poson excision (izsvak et al., ). thus, combining sb with miniplasmid technologies, such as the minicircle or the free of antibiotic resistance marker donor molecules (pfar) (marie et al., ), improves the rate of sb trans- position (sharma et al., b), and address safety issues in therapeutic applications as these miniplasmids lack bacterial and antibiotic sequences. a general feature of dna transposons is their sensi- tivity to the size of the cargo. similarly to other ele- ments (e.g. piggybac), the efficacy of transposition declines over � kb of cargo size (wang et al., c). however, in contrast to viruses, these transposons do not have an absolute limit regarding their cargo cap- acity. indeed, both sb and piggybac were reported to be capable of mobilizing giant molecules of dna, such as bacterial artificial chromosomes (bacs) (li et al., ; rostovskaya et al., ). the strategy of mimick- ing naturally occurring configurations of certain bacter- ial transposons that are adapted to carry extra sequences (e.g. antibiotic resistance genes) could sig- nificantly increase the cargo capacity of sb (zayed et al., ). in the “sandwich” (sa) configuration, the cargo dna to be mobilized is flanked by two complete sb ele- ments arranged in an inverted orientation (zayed et al., ). the sa transposon was demonstrated to have the ability to transpose up to kb transgenes (turchiano et al., ). targeting transposon integration to specific genomic loci – on the way to create a safe vector for gene therapeutic applications compared to other integration vectors, sb has a superb chance to integrate into “genomic safe harbor” loci (gogol-doring et al., ), representing currently a saf- est integrating gene transfer vehicle for application in human gene therapy. still, the genotoxic risk is not zero, and it would be desirable to direct integration to a “safe harbor” region. for targeted transposon insertion, at least one component of the transposon system, either the transposon vector dna or the transposase needs to be tethered to defined sites in the human gen- ome. proof of principle studies exist demonstrating that it is possible to direct transposon integration into pre- determined genomic loci by coupling a site-specific dna binding domain (dbd) to the sb transposase (ammar et al., a; ivics et al., ; voigt et al., ; yant et al., ) (figure ). although sb transposase is sensitive for tagging, it was possible to fuse various dbds to the n-terminus of the transposase (figure a). the first demonstration that the targeting strategy works was using the tetr/ tre system. this highly specific dna-recognition system consists of the bacterial tetracycline repressor (tetr) that binds to the tetracycline response element (tre). intriguingly, sb transposon integration could be enriched by -fold to an artificially generated tre genomic locus by using a tetr-sb fusion protein in human hela cells (ivics et al., ). the targeting was region-specific as it occurred in a . kb window around the targeted sequence (ivics et al., ). fusion of the sb transposase with the gal dbd also showed an enrichment of transposon insertions in � -bp window around the targeted sites in cultured human cells (yant et al., ). transposon targeting was also successful using a polydactyl zn-finger dbd, e c, specifically recognizing a unique sequence on human chromosome (voigt et al., ; yant et al., ) (figure a). another attempt was taking advantage of the locus- specific integration system of adeno-associated virus (aav). the aav rep protein binds to naturally existing recognition sequences (rrss) in the human genome, and mediates viral integration into nearby sites. a fusion protein consisting of the n-terminal dbd of rep and the sb transposase was generated. remarkably, the rep-sb yielded a -fold enrichment of transposition near the targeted rrs when supplied in the form of plasmid dna (ammar et al., a) (figure a). although it is a real challenge to target a single gen- omic locus, it might be a feasible approach to target a critical reviews in biochemistry and molecular biology repetitive region in the human genome. zn-finger dbd was designed and fused to the sb transposase in a strategy to target multiple genomic loci simultaneously, recognizing line- sequences that occur repetitively in the human genome (voigt et al., ). approximately, a four-fold enrichment of targeted sb insertions was achieved by targeting line- repeats, yielding � % overall frequency of insertion into line- genome wide (figure a). targeted transposition events into a chromosomally integrated tre or into endogenous matrix attachment regions (mars) were recovered by employing targeting fusion proteins (lexa-saf) that bind to the engineered transposon dna (ivics et al., ) (figure b). intriguingly, targeted transposition could also be achieved without fusing dbd directly to the full-length sb transposase. indeed, targeted transposition could be achieved at similar (or even better) frequencies by fus- ing the dbd (tetr, rep) to the n-terminal hth domain of the sb transposase, spanning amino acids (n ) (ammar et al., a; ivics et al., ; voigt et al., ) (figure c). n was previously shown to mediate pro- tein–protein interactions between transposase subunits, and is assumed to bind the hdr (the enhancer sequence in the ir) (izsvak et al., ). presumably, binding of n to hdr occurs in the pre-integration protein-dna complex. the most significant advantage of such a molecular design is that the transposase itself does not need to be engineered. thus, the negative effects of direct dbd-transposase fusion on transpos- ition activity can be eliminated (figure c). the above studies indicate the feasibility of directed transposon integration and highlight poten- tial means for future development. in all these approaches, the high specificity of the dna-recogni- tion domain is crucial. furthermore, ideally, the sequence of the selected target site should resemble an sb target site. in comparison to site-specific gen- ome editing performed by a zf-nuclease, the mech- anism of transposon targeting is principally different. in contrast to the nuclease-coupled genome-targeting approaches, the transposition would integrate the transposon/cargo cassette into the genome without generating unwanted dsbs in the genome as a side effect of the reaction (off-target effect). on the other side, targeting efficacy might not reach %, still transposon targeting could significantly enrich inte- gration in close proximity of the target site. furthermore, in contrast to genome-editing techni- ques, transposons are suitable to deliver large cargos in a large variety of cells. in addition, compared to targeted nuclease approaches, transposition does not depend on the relatively inefficient homology- dependent dsb repair of the cell. to ensure stability of the integration, the remobiliza- tion (re-hopping) frequency of the integrated cassette should be negligible. the frequency of sb figure . modulating sleeping beauty target site specificity. strategies to increase target site specificity of sleeping beauty integration. (a) fusing a dna-binding domain (dbd) (dark blue) to the n-terminus of the sb transposase (red). the affin- ity of dbd to dna-binding domain region (dbdr) could direct transposon integration. (b) co-delivery of a fusion construct with two dbds, where dbd (cyan) binds an engineered region in the transposon (dbd r, cyan), while dbd (orange) recognizes a genomic target sequence (dbd r, orange). (c) alternatively the sb system can be co-delivered with a a fusion protein, where a dbd (brown) is fused to an n-terminal, sb transposase derived peptide, n (green), a natural inter- action partner of the full-length sb transposase. a color ver- sion of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). s. a. narayanavari et al. http://www.informahealthcare.com/bmg remobilization was estimated to be relatively low (riordan et al., ). nevertheless, manipulating the half-life of the transposase by targeting it to cellular protein degradation pathways could further improve the safety of sb-mediated gene delivery in clinical applications. sleeping beauty-based transposon-viral hybrids combine viral delivery with unbiased-random integration profile as sb is a non-viral system, the efficacy of its nuclear delivery is a challenge. importantly, combining the transposon vector with cutting-edge non-viral delivery, like nucleofection and lipofection (for review see (izsvak et al., )) has been optimized. delivery using nucleo- fection has been approved for clinical application (maiti et al., ). nanotechnology seems to open novel opportunities in efficient non-viral delivery, and can be combined with cell type specific targeting (kren et al., ; wang et al., ). in an alternative approach, sev- eral laboratories have generated transposon-viral hybrid vectors (table ). viral vectors are excellent gene deliv- ery vehicles due to their intrinsic ability in transporting genetic cargos from outside to inside of the cell by crossing membrane barriers. the transposon-viral hybrids were constructed with the expectation that the effectiveness of viral delivery can be combined with the safety features of sb integration (figure ) (table ). recently, advanced deep sequencing technology coupled with bioinformatic analysis was utilized to char- acterize the integration profiles of various vectors (berry et al., ; de jong et al., ; gogol-doring et al., ) (figure ) (table ). such studies can help to fore- cast the potential risk of using different vectors. integrating vectors based on both moloney murine leu- kemia virus (mlv) have been reported to cause severe adverse effects after gene transfer in clinical trials. besides biased integrations, these vectors could cause problems by transactivating cellular promoters (e.g. oncogenes), resulting in clonal expansion of engineered cells. for instance, the mutagenic potential of mlv- based vectors have been reported in multiple clinical gene therapy trials: scid-x (hacein-bey-abina et al., ), (deichmann et al., ; hacein-bey-abina et al., ; howe et al., ; thrasher et al., ), x-cgd (stein et al., ) and was (braun et al., ). furthermore, recent analyses also demonstrate that hiv table . various sleeping beauty-viral hybrid technologies. hybrid technology delivering vehicle integration machinery advantages references adeno/sb recombinant adenovirus sb transposase � high transduction efficiency � sb-mediated unbiased, random integration profile � stable long term expression � capable of integrating large genetic cargos (yant et al., ) aav/sb recombinant aav (zhang et al., ) hsv- amplicon/sb hsv- (bowers et al., ; de silva et al., a; de silva et al., b; peterson et al., ) baculo/sb baculovirus (luo et al., ; turunen et al., ) idlv/sb idlv (moldt et al., ; staunstrup et al., ; vink et al., ; ) adeno: adenovirus; aav: adeno associated virus; idlv: integrase defective lentivirus; hsv- : herpes simplex virus amplicon; baculo: baculovirus note: the transposase (highlighted in green) and the transposon (highlighted in red) plasmids can be packaged into various recombinant viruses. a col- ored version is available online (www.informahealthcare.com/bmg). critical reviews in biochemistry and molecular biology www.informahealthcare.com/bmg integration sites can play a critical role in clonal expan- sion and persistence of hiv-infected cells (maldarelli et al., ; wagner et al., ), pinpointing to the risk of clinical application of hiv-based (lentiviral) vectors. importantly, based on the frequencies of integration into genome safe harbors (gshs), sb ranks top among four integrating genetic elements (sb, mlv, hiv, piggybac) in the context of human applications (gogol- doring et al., ). in an attempt to modulate the integration profile of a lentiviral gene delivery system, the viral integration machinery was replaced with the sb transposase (staunstrup et al., ; vink et al., ). the employ- ment of the integrase-defective lentiviral vectors (idlvs) figure . sleeping beauty transposon-based hybrid vectors. to circumvent the hindrance associated with transfection efficiency of naked dna plasmids, the sb system, including both the transposase (tnpase/sb – green dots for protein) and the transposon (tnp/goi – red) can be packaged into various recombinant viruses like adeno, aav, idlv, hsv- and baculovirus for delivery (by transduction) into the cytoplasm. the delivery is followed by quick and stable genomic integration of the cargo/goi, mediated by the sb system as shown in follow-up qualitative time plot. abbreviations: goi: gene of interest; adeno: adenovirus; aav: adeno associated virus; idlv: integrase defective lentivirus; hsv- : herpes simplex virus amplicon; baculo: baculovirus. a color version of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). s. a. narayanavari et al. http://www.informahealthcare.com/bmg ta b le . d iff er en t ty p es of vi ra l ve ct or s us ed fo r g en e th er ap y. v ec to r sa fe ty g en et ic m at er ia l pa ck ag in g ca p ac it y tr op is m in fla m m at or y p ot en ti al v ec to r g en om e fo rm s re m ar ks be n ef it s en ve lo pe d' re tr ov ir us bs l- or if am p h ot ro p ic bs l- / þ rn a kb d iv id in g ce lls on ly lo w in te g ra te d � ri sk of in se rt io n al m ut ag en es is � bi as ed in te g ra ti on p at te rn pe rs is te n t g en e tr an sf er in d iv id in g ce lls le n ti vi ru s bs l- rn a kb br oa d lo w in te g ra te d pe rs is te n t g en e tr an sf er in m os t ti ss ue s h sv - bs l- d sd n a u p to kb st ro n g fo r n eu ro n s h ig h ep is om al ri sk of in fla m m at io n la rg e p ac ka g in g ca p ac it y ba cu lo vi ru s bs l- d sd n a kb br oa d h ig h ep is om al in ac ti va te d b y se ru m co m p le m en t lo w cy to to xi ci ty n on -e nv el op ed a d en ov ir us bs l- d sd n a up to kb br oa d h ig h ep is om al ri sk of in fla m m at io n ef fic ie n t tr an sd uc ti on fo r m os t ti ss ue s a a v bs l- ss d n a < kb br oa d w it h ex ce p ti on a lo w ep is om al (> % ) sm al l p ac ka g in g ca p ac it y � n on -i n fla m m at or y � n on -p at h og en ic a h em at op oi et ic ce lls ar e an ex ce p ti on . critical reviews in biochemistry and molecular biology in combination with the sb system made it possible to alter the biased viral integration profile (figure ). the hybrid vector-mediated transposition reduced the num- ber of insertions within genes to %, overriding the biased integration profile of the viral vector, and thus promoting a safer integration profile of sb x (moldt et al., ). these data clearly indicate that the unbiased integration profile of sb can be maintained independently of the virus used for delivery. the adeno/transposon system consists of the two- component transposon system (transposon and sb x transposase) delivered by adenoviral vectors (figure ). while adenoviral delivery is efficient, transgene expres- sion is transient, due to the episomal nature of the adenovirus (table ). the hybrid adeno/transposon vec- tor enables the integration of the gene of interest, thereby providing a sustainable expression of the thera- peutic gene (yant et al., ) (table ). this hybrid sys- tem has been proved to stably express factor ix as a treatment for hemophilia b in dogs with negligible tox- icity (hausl et al., ). the adeno/transposon hybrid vector has several attractive features. first, it is capable of integrating large cargos (over / kbs). second, due to the required low amount of therapeutic vector, the toxicity (provoked immune response) of the admin- istration is low, and there in no requirement for repeated administration. furthermore, by developing viruses of different tropism, the adenovirus has a prem- ise to be suitable of targeting different cell types. aav vectors have been shown to be one of the most promising vectors for therapeutic gene delivery, and were involved in several clinical trials, primarily in slowly dividing cells (mingozzi & high, ). due to the stable integration, the hybrid aav/transposon (sb x) pro- vides sustained gene expression (zhang et al., ), that generally declines in fast dividing cells, as the sim- ple aav vector remains episomal (table ). while aav vectors have limited cargo capacity, several serotypes are available. importantly, the hybrid adeno/transposon and aav/transposon vectors exhibit sb x-directed, random integration profile. sb-based hybrid vectors were also developed using herpes simplex virus (hsv) vectors (bowers et al., ; de silva et al., a; de silva et al., b; peterson et al., ) (figure ). again, the hybrid system exhibits unbiased integration profile and a premise to efficiently deliver and support stable expression in neuronal cells. the hsv/sb vector has opened up the possibility of treating early-onset neurological disorders with its cap- acity to integrate a therapeutic gene within a neuronal precursor cell population within the fetal brain. baculovirus mediates short-term expression in the transduced cells as a result of the non-replicative and non-integrative nature of the baculovirus (chen et al., ; kost et al., ) (table ). to circumvent these problems, a hybrid baculovirus/sb vector was generated for efficient mammalian cell transduction and sustained transgene expression (luo et al., ; turunen et al., ) (figure and table ). the baculovirus-sb vector combines the efficient baculovirus transduction with sb-mediated gene expression, alleviating the shortcom- ing of conventional baculovirus vectors. the integration preferences for the baculovirus/sb hybrid vector sys- tems are yet to be determined. awakening sleeping beauty in the clinic sb has proven successful as a gene delivery agent and the technology reached clinical level just about a dec- ade following its initial conception (williams, ). the sb system has met success as a therapeutic vector to support sustainable, long-term expression in individual organs (e.g. liver (wang et al., ), lung (belur et al., ; liu et al., a), muscle (escobar et al., ; muses et al., )) and cells (e.g. retinoid cells (johnen et al., ), keratinocytes (ortiz-urda et al., ), pri- mary t cells etc. (reviewed in (singh et al., )) of choice. the clinically relevant cell types tested include dividing- and non-dividing cells, stem cells (marg et al., ; mates et al., ; xue et al., ), including ipscs (belay et al., ), somatic stem cells and differ- entiated ones as well. sb has been systematically tested in several pre- clinical models (for review see (izsvak et al., )). importantly, no biologically or clinically relevant immunogenicity has ever been reported that signifi- cantly affects its applicability. the preclinical models included a wide range of metabolic disorders, degen- erative diseases and cancer. several metabolic disorders have been successfully modeled in rodents using the sb system. for example, it was possible to ameliorate the clinical symptoms manifested in lysosomal storage disease (aronovich et al., ; aronovich et al., ), crigler–najjar syn- drome (wang et al., ), type–i tyrosinemia (montini et al., ; pan et al., ; wilber et al., ), type–i diabetes (he et al., ) and hypercholesterolemia (turunen et al., ). it was possible to achieve long- term expression of human uridinediphosphoglucuro- nate glucuronosyltransferase- a (psb-hugt a ) in gunn rats leading to a significant reduction in serum bilirubin levels (wang et al., ). similarly, phenotypic correction was achieved by expressing fumarylacetoace- tate hydrolase (fah) (montini et al., ), human insu- lin gene precursor (he et al., ) and ldlr and vdlr genes (turunen et al., ) in mouse models. by using s. a. narayanavari et al. the sb system, it was also possible to achieve significant reduction of pulmonary arterial pressure by delivering endothelial nitric oxide synthase (enos) into a rat model of pulmonary hypertension (liu et al., a). it was possible to witness phenotypic correction by long- term stable expression of factor-viii (kren et al., ; liu et al., b; ohlfest et al., b). regarding muscular dystrophies, sb-mediated deliv- ery of dystrophin gene into muscle cells lines followed by transplantation into mouse muscles resulted in nor- mal myogenic properties without transforming into tumors (muses et al., ). restoration of dysferlin expression and with signs of muscle regeneration was also observed (escobar et al., ). the low immunogenicity of the sb system provides an opportunity to develop strategies to treat degenera- tive diseases associated with aging. the sb system was successfully used to deliver shrnas against selected mutant exons of huntington gene (htt), resulting in up to % repression of the mutant gene (chen et al., ) in a huntington disease model. therapeutic sb vectors expressing microrna- (mir- ) were also cap- able of preventing inflammatory macrophage infiltra- tion in a mouse model of pulmonary fibrosis (xiao et al., ). various therapeutic strategies to monitor (ohlfest et al., ; ohlfest et al., ) and counter tumor growth using sb have also been explored. anti-angio- genic therapy yielded promising results as it was pos- sible to achieve tumor regression by delivering endogenous angiogenesis inhibition factors i.e. an angiostatin–endostatin fusion cassette into mice bear- ing a human xenografted glioblastoma tumor (ohlfest et al., a) and metastasized colorectal carcinoma tumors (belur et al., ). in a suicide gene approach, overexpressing hsv thymidine kinase type (hsv-tk) under the htert promoter yielded successful induction of apoptosis and significant inhibition of tumor growth (song et al., ). employing the sb system in t cell adoptive immunotherapy has a great promise in treat- ing hematological malignancies (magnani et al., ). in vivo, the delivery of the therapeutic gene is fre- quently performed by hydrodynamic tail vein injections of plasmids (belur et al., ; carlson et al., ; ohlfest et al., b). by employing an adeno/sb hybrid vector in a canine model, it was possible to demon- strate that the technology was transferable from the small to large animal (dog) model (hausl et al., ). alternatively, the sb system is used to engineer cells ex vivo that are administered/transplanted to the patient to treat the disease. remarkably, this approach has already has been approved for a phase , clinical trials to fight against cancer by using engineered t cells (deniger et al., ; krishnamurthy et al., ; magnani et al., ; singh et al., ; singh et al., ), and to treat age-related macular degeneration (amd, targetamd (http://www.targetamd.eu/)). in sum, sb combines the integrating abilities of viral gene ther- apy vectors needed for stable and long-lasting trans- gene expression with the advantageous properties of easy production, simpler handling and potentially safer chromosomal integration profiles. sleeping beauty is a simple, unbiased and efficient tool to gene function annotation sb has also proved to be an invaluable tool in gene annotation. by exploiting the local hopping feature of the sb system, it was possible to decipher the genomic neighborhood of a particular integration site by remobi- lizing the transposons from individual chromosomes (keng et al., ; kokubu et al., ). the greatest suc- cess of sb has been in its use for phenotype-driven gen- etics (carlson et al., ; elso et al., ; horie et al., ; ivics & izsvak, ; izsvak et al., ; moriarity & largaespada, ). unlike a candidate-based strategy, sb transposon-based gene trapping, enhancer trapping and unbiased mutagenesis approach is suitable to iden- tify genes with unexpected phenotypes (balciunas et al., ; lu et al., ; song & cui, ). germline transgenesis in the last two decades, the applicability of the sb sys- tem as a transgenic agent has been systematically tested in almost all of the existing animal model sys- tems. sb was successfully used as a delivery vehicle for germline transgenesis in a variety of vertebrate species like in fish, including zebrafish (danio rerio) (balciunas et al., ; davidson et al., ), nile tilapia (oreochromis niloticus) (he et al., ), medaka (oryzias latipes) (grabher et al., ), in the amphibian xenopus laevis (sinzelle et al., ), in rodents (garcia diaz et al., ; garrels et al., c; ivics et al., c), rabbits (ivics et al., b), swine (garrels et al., ; ivics et al., a) and cattle (alessio et al., ; garrels et al., b; yum et al., ). pronuclear injection of the transposase in the form of mrna, the integration of the transgene flanked by recognition sequences for the transposase is faster, and can occur before the first cell division. this feature of the sb system is highly beneficial in animals, possessing a series of fast cell division that cannot be challenged by using conventional non-viral or lentiviral vectors (e.g. rabbits) (ivics et al., b; katter et al., ). the sb system has proven to be highly efficient to generate critical reviews in biochemistry and molecular biology http://www.targetamd.eu/ transgenic animals with a robust, whole-body transgene expression, with no significant transgene silencing. this feature also helps to establish tissue-specific transgenic models (katter et al., ). combining sb transgenesis with recombinase-mediated cassette exchange could be employed to test multiple expression cassettes at a single, well-characterized genomic locus (garrels et al., a). transgenic animals stably expressing specific markers could be used to monitor dynamic processes and establish various drug-testing schemes (szebenyi et al., ). although transgenic techniques were trad- itionally aimed at mice, the sb system could offer a feas- ible solution to generate transgenic versions in a large variety of animal models, and also in livestock (reviewed in (bosch et al., )). indeed, the employment of the sb system could have a positive impact on livestock production by facilitating an easy-to-use protocol to generate transgenic farm animals (hu et al., ). sleeping beauty for functional oncogenomics oncogenomic screens applying sb-mediated insertional mutagenesis have been highly productive (figure ; for review see (mann et al., ; moriarity et al., ; tschida et al., )). for the oncogenic screens, the sb system is modified to be a highly mutagenic agent. the mutagenic sb transposons were designed to induce either gain-of-function (gof) or loss-of-function (lof) mutations when inserted in or near a gene based on its genetic cargo. it is an effective method for candidate gene discovery that can aid in distinguishing driver from passenger mutations in cancer. this system has been adapted for unbiased screens to identify drivers of multiple cancer types. for example, these screens iden- tified novel genes and pathways that were causative of non-melanoma skin cancer (quintana et al., ), colo- rectal carcinoma (starr et al., ; starr et al., ), non-viral hepato-cellular carcinoma (keng et al., ), leukemia and lymphoma (collier et al., ), b-cell pre- cursor acute lymphoblastic leukemia (bcp-all) (van der weyden et al., ), high grade astrocytoma (bender et al., ), schwann cell sarcoma – in particular, malig- nant peripheral nerve sheath tumor (rahrmann et al., ), hepatitis b virus-induced hepato-cellular carcin- oma (bard-chapeau et al., ), histiocytic sarcoma (been et al., ), osteosarcoma (moriarity et al., ), prostate adenocarcinoma (rahrmann et al., ) and non-small cell lung carcinoma (dorr et al., ). recently oncogenomic screens have also been adapted for functional annotation of cancer genomes by ena- bling insertional mutagenesis screens in higher eukaryotes that are not amenable to germline transgenesis, including humans (chen et al., ; molyneux et al., ). these cancer screens apart from revealing previously implicated genes have also led to the discovery of several new potential drivers of cancers thereby providing new targets for chemical and genetic therapies. future directions the future challenges of the sb-mediated therapeutic approaches include a further improvement of safety and efficacy. a tighter regulation of transposase expres- sion would be necessary to guarantee the stability of the transgene expression. targeted gene insertion into predetermined safe loci in the human genome is quite ambitious, but might be feasible in the near future. the efficacy of delivery is still a bottleneck problem of sb- mediated applications. coupling sb to cutting edge non-viral delivery techniques should be further explored (flow-through electroporation, nanotechnology, etc.). alternatively, coupling of sb for its safety features with viral vectors for their efficient delivery could be an ideal combination. the continuously accumulating know- ledge on host–transposon interactions could further fuel applications by lifting existing limitations. in this revolutionary era, it became possible to genet- ically engineer a number of organisms. the field of gen- ome engineering is developing fast, and offers more and more sophisticated tools to modify the genome. depending on the aim, the evaluation of pros and cons of any particular engineering tool helps to identify the most appropriate strategy. importantly, the tools can be combined with each other or with other recombination systems. remarkably, now it is possible to precisely edit the genome (zf-/talen-nucleases, crispr-cas sys- tem). for therapeutic applications, safety and feasibility still remain the key issues. with respect to efficiency, a targeted nuclease would be an ideal tool to knockout or engineer a short specific dna region. however, trans- posons might be a better choice to deliver large cargos in a variety of cell types. this is because in contrast to targeted nuclease systems, transposons are not dependent on the homology-dependent repair path- ways of the host, whose efficiency represents a bottle- neck of targeted genome-modifications in certain cell types. finally, while nuclease-coupled targeting systems can precisely edit a desired genomic locus, they can generate undesired double stand breaks in the genome as off-target events. on the other hand, transposons do not damage the genome with unwanted dsbs, but their untargeted integration can be potentially mutagenic in clinical applications. targeting transposition to safe har- bor genomic location could be feasible. for functional genomic application (phenotypic screens), transposons s. a. narayanavari et al. figure . sleeping beauty transposon-based functional oncogenomics. an overall scheme depicting key steps for employing the sb system for oncogenomics. the conditional insertional mutagenesis begins with the generation of transgenic lineages of the chosen model system, popularly referred to as the mutator (transposon) and jump-starter (transposase) lineages. the mutator lineage is transgenic for a custom-engineered transposon (red double-headed arrow) that can be mobilized by the sb transposase (green pie). the mutator transposon is designed so that by virtue, it can promote, alter or even terminate expression of endogenous reading frames upon sb mediated insertion in either orientations eventually leading to gain and/or loss of functions. this entire scenario can be rendered “conditional” by restricting the activity of sb to specific tissues or organs of choice by placing it under the command of appropriate promoter. the double-transgenic animals are aged for development of relevant cancer phenotypes. the next step involves the identification of the transposon integration sites that very likely resulted in the observed phenotypes. this primarily involves extraction and digestion of the dna from which these sites are recovered by lm-pcr, barcoded and sequenced by next gen- eration sequencing. the recovered sites are mapped on the genome, and subjected to a statistical analysis to identify common inte- gration sites (ciss) that were present in majority of the tumors. shortlisted candidates are further validated by reverse genetic approach as illustrated in the figure. abbreviations: sa: splice acceptor; pa: poly-a tail; pro: promoter; sd: splice donor; gof: gain of function; lof: loss of function; chr: chromosome; lm-pcr: linker-mediated pcr; ngs: next generation sequencing; cis: common inte- gration sites. a color version of the figure is available online (see color version of this figure at www.informahealthcare.com/bmg). critical reviews in biochemistry and molecular biology http://www.informahealthcare.com/bmg have the advantage of being unbiased with respect to the sequences they mutagenize, whereas gene-editing tools are biased by their very nature. it is likely, that transposons will continue to uniquely contribute to the genome-engineering toolbox for many years to come. acknowledgments zsuzsanna izsv�ak (ziz) and zolt�an ivics would like to thank the past and present members of their teams, “mobile dna” and “transposition and genome engineering” for their dedi- cated work and contribution. disclosure statement the authors report no declarations of interest. funding european research council, . / [erc- -adg ]. references alessio ap, fili ae, garrels w, et al. 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( ). hybrid adeno- associated viral vectors utilizing transposase-mediated somatic integration for stable transgene expression in human cells. plos one :e . s. a. narayanavari et al. sleeping beauty transposition: from biology to applications introduction the sleeping beauty transposon mechanism of sleeping beauty transposition structure of the sleeping beauty transposase the dna-binding domain the catalytic domain transposonhost interactions transcriptional regulation by hmgxb dna methylation enhances sleeping beauty transposon excision hmgb assists pre-cleavage complex formation assistance from the host dna repair to seal sleeping beauty inflicted dna damage modulation of the cell cycle protection from a self-destructive autointegration process integration site distribution regulating transcription from sleeping beauty by rna interference overproduction inhibition is autoregulatory translating sleeping beauty transposition biology the two-component transposon vector system sleeping beauty for biotechnology sleeping beauty to generate induced pluripotent stem cells enriching for human nave-like pluripotent stem cell populations optimizing sleeping beauty for gene therapy an optimal vector for the cargo targeting transposon integration to specific genomic loci on the way to create a safe vector for gene therapeutic applications sleeping beauty-based transposon-viral hybrids combine viral delivery with unbiased-random integration profile awakening sleeping beauty in the clinic sleeping beauty is a simple, unbiased and efficient tool to gene function annotation germline transgenesis sleeping beauty for functional oncogenomics future directions acknowledgments disclosure statement references the british journal of psychiatry | cambridge core skip to main content accessibility help we use cookies to distinguish you from other users and to provide you with a better experience on our websites. close this message to accept cookies or find out how to manage your cookie settings. login alert cancel log in × × home only search content i have access to home log in register browse subjects what we publish services about cambridge core cart cart access provided by carnegie mellon university manage institution login logged in as: carnegie mellon university manage institution login register register log in cart < back to search results home journals the british journal of psychiatry english | français the british journal of psychiatry search within full text search within journal search within society submit your article information submit your article you are leaving cambridge core and will be taken to this journal's article submission site. cancel leave now × other actions submit your article information visit: journal home journal home accepted manuscripts firstview articles latest issue all issues most read subscribe open access articles there is currently a delay in the posting of accepted eletters to cambridge core. we apologise for the inconvenience. access: subscribed contains open access on the cover continues the asylum journal ( - 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( ) altered images : understanding the influence of unrealistic images and beauty aspirations. health care analysis. permanent wrap url: http://wrap.warwick.ac.uk/ copyright and reuse: the warwick research archive portal (wrap) makes this work of researchers of the university of warwick available open access under the following conditions. this article is made available under the creative commons attribution . international license (cc by . ) and may be reused according to the conditions of the license. for more details see: http://creativecommons.org/licenses/by/ . / a note on versions: the version presented in wrap is the published version, or, version of record, and may be cited as it appears here. for more information, please contact the wrap team at: wrap@warwick.ac.uk http://go.warwick.ac.uk/lib-publications http://go.warwick.ac.uk/lib-publications http://wrap.warwick.ac.uk/ http://creativecommons.org/licenses/by/ . / mailto:wrap@warwick.ac.uk o r i g i n a l a r t i c l e altered images: understanding the influence of unrealistic images and beauty aspirations fiona maccallum • heather widdows � the author(s) . this article is published with open access at springerlink.com abstract in this paper we consider the impact of digitally altered images on individuals’ body satisfaction and beauty aspirations. drawing on current psycho- logical literature we consider interventions designed to increase knowledge about the ubiquity and unreality of digital images and, in the form of labelling, provide information to the consumer. such interventions are intended to address the nega- tive consequences of unrealistic beauty ideals. however, contrary to expectations, such initiatives may not be effective, especially in the long-term, and may even be counter-productive. we seek to understand this phenomenon of our continued aspiration for beauty ideals we know to be unreal and even impossible. we draw on our respective disciplines to offer psychological and philosophical accounts for why this might be. we conclude that beauty ideals are deeply embedded in our aspira- tions, practices, and in our constructions of ourselves. given this, it is not surprising that simply increasing knowledge, or providing information, will be insufficient to challenge them. keywords beauty ideals � digital modification � body image � media introduction in this paper we consider the impact of digitally altered images on individuals’ body satisfaction and beauty aspirations. the proliferation of altered images is such that it is now standard for print and on-line images to be altered in some way: from relatively minor retouching (whitening teeth and eyes, smoothing wrinkles, and & fiona maccallum fiona.maccallum@warwick.ac.uk department of psychology, university of warwick, coventry cv al, uk department of philosophy, university of birmingham, edgbaston, birmingham b tt, uk health care anal doi . /s - - - http://orcid.org/ - - - http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf erasing blemishes) to more dramatic modification (elongating limbs and slimming waists, thighs and arms). we draw on the psychological literature to outline current understandings of the relationship between images of ideal (particularly thin) bodies on body image and the ideal body to which we aspire. we then consider interventions which seek to counter the influence of such altered images—those of media literacy and labelling—and focus on the troubling finding that knowing that images have been altered does not make us less likely to aspire to the ideals they represent. on the contrary it seems that labelling images as ‘‘manipulated’’ or ‘‘enhanced’’ may even increase our desire to aspire to the ideal portrayed. we seek to offer possible explanations for why we continue to desire to attain such ideals, even when we know that they are not real. we draw on our respective disciplines to offer a psychological and philosophical account for the allure of such beauty ideals. digital images and body image from a sociocultural perspective on the formation of body perceptions and satisfaction, viewing of media depictions is an influential route of transmission of cultural ideals of beauty [ ]. extensive research supports this, with exposure to visual mass media depicting idealised bodies being associated with body image disturbance in both experimental and correlational studies [ ]. although most frequently investigated in adolescent girls and young women, similar relationships are also seen in the midlife stage; viewing of media featuring ‘‘ageing beauties’’ (who have the body shape and size of younger women) predicted disordered eating, greater discrepancy between actual and desired body size, and stricter food choices in women aged – [ ]. this is not to say that images are passively and uncritically received [ ]. rather, images are interpreted, critiqued, rejected and renegotiated as individuals and groups. this said, an increasingly globalised and homogenised beauty ideal is emerging, which gives particular prominence to thinness and youth. the increasing visual emphasis on these attributes over the last few decades has been paralleled by rises in rates of body dissatisfaction with both women and men feeling unhappy with their physical appearance [ ]. negative body image can be viewed as a core aspect of psychological wellbeing, relating not just to appearance-changing behaviours such as dysfunctional eating behaviours, but also to general emotional difficulties such as distress and depression [ ], making it an issue of real concern. digital alteration means that increasingly the images with which we are bombarded are ever more idealised and unreal, and this exacerbates the problem by setting ever higher expectations of what it is to be normal, good enough, or perfect. airbrushing to remove imperfections, whiten teeth, elongate and narrow limbs, slim waists, increase breasts, is not only accepted but expected in the fashion and entertainment industries [ ]. low-cost technology means that modification is not confined to the photographer’s studio but can be implemented via apps in order to that is not to say that this is a simple causal link. the extent to which an individual’s self-image is affected by exposure to visual media will also depend on personal characteristics, e.g. those who already have high levels of internalisation of sociocultural standards of appearance may be more vulnerable to media influence. health care anal ‘‘improve’’ photos posted on social media, exhorting users to ‘‘get instagram ready!’’ the ubiquity of these techniques can be regarded as a factor in creating increasingly unrealistic beauty aspirations, leading to negative consequences of increased body dissatisfaction with its adverse implications. revealing the unreal in response a number of interventions have been suggested, and we consider two of these: (a) education programmes in schools including components focusing on media literacy and the artificial nature of images (see e.g. [ ]), and (b) the explicit labelling of images as digitally altered. several types of school-based interventions aimed at improving body image have been trialled, and a meta-analysis found that those which were effective included content relating to media literacy and the way in which media images can be manipulated, supporting the first proposed approach [ ]. however, the effect sizes of these programmes were only small, and improvements were not always maintained post-intervention [ ]. one difficulty may lie in our ability to know when a photograph has actually been altered. although computational methods can be designed to detect image tampering, it is not so easy with the naked eye [ ]. a recent experiment using real-life photographs showed that when presented with an airbrushed image (teeth whitened, spots/wrinkles removed, and so on) and asked to decide if it was original or digitally altered, more than half of the participants did not detect it was manipulated, and of those who did, many were unable to identify which aspect had been changed [ ]. furthermore, people’s belief about the extent of image manipulation in general did not improve their ability to detect and locate the alterations. importantly then, simply being aware that a lot of images are modified does not mean we are any better at spotting them in the real world, suggesting that media literacy training may not be enough. if knowing that images generally are manipulated is not sufficient, perhaps being told which specific images have been altered would be beneficial. this would have the additional advantage of reaching all individuals interacting with the media rather than just those still at school. in both israel and france, it is now a legal requirement for advertisers to disclose when photographs of models have been digitally modified. australia has a voluntary code of conduct for the fashion, media, and advertising industries, requesting that disclaimer labels be included on altered images, and similar policies have been put forward in other countries such as norway and the uk. but do such strategies work in reducing the idealisation of the images, and thus the negative effects on our self-perceptions? some initial research on the effects of labelling was promising with an australian study finding that including a label warning that an image had been digitally altered reduced the level of body dissatisfaction created by viewing a thin ideal image [ ]. however, a growing number of studies have found no amelioration of the negative effects of media images by labelling, and in fact the opposite may be the case. an experiment by bissell presented one group of women with information about the general use of digital enhancement in the media and then with images of models in health care anal swimsuits with the tagline ‘‘the image below has been digitally manipulated to enhance the model’s appearance’’ [ ]. the results showed that, compared to a second group of women who viewed the same images with no statement and no prior information, those in the experimental group reported a greater desire to look like the models, and rated the models as more attractive. this ‘‘boomerang effect’’, where awareness of digital modification increases rather than diminishes the influence of the images has also been found using retouched images of normal people, to control for the effect of the thin-ideal model [ ]. in this study, male and female adolescents viewed photographs of same gender young adults that were either not retouched, were retouched to remove blemishes and subtly improve body contours, and labelled as so, or were retouched and not labelled. physical self-esteem decreased and objectified body consciousness increased following exposure to the images only in those adolescents who were informed about the digital alteration. these undesired effects may also be durable across time. a single exposure to a thin-ideal image with a disclaimer label (worded in the same way as the then- proposed french law—‘‘this image has been altered to modify a person’s bodily appearance’’) increased accessibility to negative thoughts, which was used as an implicit measure of an adverse cognitive-emotional response, immediately after viewing [ ]. importantly, these effects were also seen when participants viewed the image again, with no disclaimer this time, both weeks and months later. the implication from the research is that if an image is considered desirable, digital alteration disclaimers are not helpful and may actually be harmful. one study found that a specific information label attached to images of thin media models. i.e. ‘‘these models are underweight’’, did have the desired effect of reducing negative body perceptions [ ]. as a policy strategy, the feasibility of asking the advertising and fashion industry to adopt labels worded in this way might be questionable as it would be likely to have negative commercial consequences, although it could also have the positive effect of discouraging the use of underweight models. such studies have limitations in what they reveal, and the impact of images is cumulative, and dependant on social and cultural context. but, and this is the point, the ubiquity of increasingly unrealistic digital images does feed into our beauty ideals and aspirations, and it seems that we continue to hold digitally modified images as ideals even when we are told that they are not ‘‘real’’. if this is the case then simply providing more information, or knowledge, is not sufficient. in the rest of the paper we suggest three possible explanations for what at first glance seems counter-intuitive, that knowing something is unreal—even impossible—does not stop us aspiring to it. ideals, comparisons and ourselves before considering the question from a theoretical perspective, it is helpful to understand what is happening in terms of perceptual processing, i.e. what our senses do with the labelled images. here, we draw first on selimbegovic and chatard who, the use of excessively thin models in itself raises ethical concerns, and is regulated against in some countries including france, israel, italy and spain. health care anal suggested that disclaimer labels actually draw more visual attention to the image, leading to ‘‘deeper’’ processing of it [ ]. the result is more focus on the semantics of the image, its meaning and implications, i.e. viewers are reminded that ‘‘being beautiful means looking like this’’. this would also explain the durability of the effect whereby deeper processing involves more elaborate encoding in memory, and thus easier recall. a similar account by tiggemann and colleagues was proposed for the findings of another study where specifically worded labels, such as ‘‘warning: this image has been digitally altered to smooth skin tone and slim arms and legs’’, were found to increase body dissatisfaction for women who had pre-existing high levels of the tendency to compare their appearance to others [ ]. the authors suggested that the warning labels directed greater attention to the model’s body, and particularly those areas named as altered, than would be the case with a generic warning label or with no label at all. they went on to investigate this speculation using eye tracking technology, by presenting women with fashion advertisements depicting the thin ideal, and labelled with a specific disclaimer referring to target areas of the body, e.g. waist, or with a generic disclaimer stating that the image had been digitally altered, or with no disclaimer [ ]. measurements of the number and the duration of gazes towards the target areas of the models’ bodies found that women looked at these areas more often and for longer in both the disclaimer label conditions, and even more so in the specific than the generic label condition. this additional attention predicted an increase in body dissatisfaction for those who saw the specific warning labels. thus, far from encouraging us to discount altered images, labelling seems to make us take more notice of them. the finding that women high in social comparison were more likely to experience increased dissatisfaction when viewing specific warning labels ties in with one potential theoretical explanation [ ]. social comparison theory, as first put forward by festinger, postulates that humans have a desire to self-evaluate, and that where no objective measurement of our attributes is possible, as with appearance, we do so through comparison with others [ ]. although to some extent, this seeking of information is a rational tactic when direct assessments are unavailable, the consequence is that our self-worth judgements depend on the chosen comparison target. ‘‘upwards’’ comparisons, where we perceive the comparator as higher in the particular attribute will lead to more unfavourable self-evaluation. social comparison has consistently been demonstrated as one of the processes determining body dissatisfaction [ ]. when idealised media images are used as comparison standards, upwards comparisons lead to more negative perceptions of our own appearance, accounting for some of the influence of the media on body image [ ]. the rationale for recommending disclaimer labels initially was that social comparison targets are chosen based on their self-relevance and their salience [ , ]. therefore, awareness of digital enhancement should lead to less comparison and less consequent body dissatisfaction since the image is known to be artificial and so not a relevant and salient target [ ]. however, paying in festinger’s original conceptualisation, social comparison was premised on peer comparison; however, more recent adaptations suggest that the strength of the cultural ideals of attractiveness mean that people will not dismiss models and other idealised figures as comparison targets. because women know they will be judged against these standards, the idealised images become relevant targets. health care anal more attention to the image as discussed above seems to have the opposite effect of increasing the felt relevance, and encouraging upwards comparisons. effectively, the enhanced attention reinforces our conception of the ideal, and we are reminded that we do not match up. thus, labelling images as digitally altered exacerbates negative social comparisons with ideal images, which in turn exacerbates criticism of our own appearance. a second framework which could explain why digital modification affects us negatively even when we are aware of it is that of self-discrepancy theory [ ]. this proposes that individuals hold self-perceptions in three domains: the ‘‘actual’’ self (the attributes we believe we have); the ‘‘ideal’’ self (the attributes we aspire to have); and the ‘‘ought’’ self (the attributes we believe we should have). when discrepancies arise between these perceptions, it can lead to negative emotions and cognitions. specifically, discrepancy between the actual self and the ideal self can result in dejection-related emotions such as disappointment and sadness, whereas discrepancy between the actual self and the ought self can result in agitation-related emotions such as anxiety and guilt. these types of discomfort lead people to engage in behaviours designed to resolve the discrepancies. research on media influences on body satisfaction has focused mainly on the actual-ideal discrepancy and how media imagery can affect the formulation of the ideal self, making it more unattainable thus increasing distress, and making appearance-changing behaviours such as eating disorders more likely [ ]. however, viewing idealised media can also increase the discrepancies between the actual and the ought self, resulting in behaviours such as restricted eating in the presence of others, in order to give the impression to other social agents that one is trying to achieve the appearance we believe society obliges us to have [ ]. the labelling of images as digitally altered could affect the ideal self, with the processes of increased attention and deeper processing leading to further internalisation of the attributes of the image as ones we would like to possess. equally though, the manipulation could be interpreted as being considered the socially desirable image, and therefore possessing attributes we ought to have. even when we know the model does not look like that, the pressure on the ought self could put an obligation on us to try to emulate the image, and make us feel guilty when we do not. taken together then, there are psychological accounts which offer some reasons for why knowing that images are unreal may do little to stop us seeking to attain them, and in fact may further reinforce and embed unrealistic beauty ideals. beauty as an ethical ideal turning from the psychological literature to the philosophical, we can explain the continued power of beauty ideals, however unreal, if we recognise that, at least for some women in some instances, beauty ideals are functioning as ethical ideals. by this, we mean that the extent to which a women conforms to the beauty ideal determines how morally good she judges herself (and others) and how she evaluates health care anal actions as right and good, opposed to wrong and bad. the use of moral language here we regard as accurate and significant and not simply a matter of language. ‘‘i should go to the gym’’ because i should improve, is moral in that it is about what is required to be judged good (or good enough). if this is the case then it is not surprising that knowing that beauty ideals are unreal and unattainable does nothing to reduce the wish to attain such ideals. that there are moral and ethical elements in beauty ideals, standards and discourses is overtly the case. many people judge themselves according to their success and failure in beauty terms. this is true both with regard to achieving long-term goals—we judge ourselves successful when we’ve attained some aspect of the ideal (reached our goal weight, filled our wrinkles or firmed our thighs)—and in terms of daily habits and practices—we are successful when we make it to the gym, stick to the diet, get a manicure or undergo some procedure. success here is not just aesthetic success (although it may be that too), but moral. for instance, when we deem ourselves successful for engaging in many of these practices the success is only moral: sticking to our calorie count for the day or making it to our exercise class has very little impact upon how we look in the short term and the data on diets suggests that very few of us dramatically change our size over the long term. however, meeting the goal is less important than engaging in the practices, even though we may never reach the desired goal (and we know that it is unlikely), on a day-to-day basis we can still succeed. that beauty is functioning as an ethical ideal—providing values and standards against which we judge ourselves and others—is particularly clear when we consider what it means to ‘‘fail’’. beauty failure results in explicit moral judgements of culpability and responsibility, making beauty failures effectively equivalent to vices. that this is the case is hinted at in the language of beauty as employed by both women and the beauty business (advertisers and women’s magazines): be ‘‘your best self’’, ‘‘the best you can be’’, ‘‘it’s still you, but the best version of you’’, ‘‘the real you’’. language such as this directly reveals and communicates the ethical nature of the beauty ideal. you should strive for that best, real, you; you ought to invest in yourself, because ‘‘you’re worth it’’, ‘‘you deserve it’’ and ‘‘you owe it to yourself’’. the converse is also true. to fail to engage is to admit or accept that ‘‘you’re not worth it’’: ‘‘you let yourself go!’’ unpacking the implications of this reveals the moral assumptions underpinning the framework: it implies not only that this argument is developed by one of the authors as part of a larger project [ ]. the claim that beauty ideals are functioning as ethical ideals is in part a virtue based one, that for many to conform to the beauty ideal is considered virtuous (this is true externally, when character-traits are judged from appearance, and internally when we consider ourselves ‘‘good’’ when we diet or go to the gym or all manner of beauty practices). many judge actions morally ‘‘good’’ or ‘‘right’’ when they are likely to deliver a better or more ideal body. ‘‘should’’ here is a moral ‘‘should’’. it is not the prudential should of ‘‘you should write a will’’, or the preference should of ‘‘you should have this pizza, its great!’’. for instance, in her analysis of weight watchers, cressida heyes argues that part of the logic of weight watchers is the recognition that we have to keep going and keep striving. it is never done, and when we stop dieting, ‘‘we mourn not only the loss of the future thin self that, even if not attained, can always be looked forward to, but also the loss of a forum in which, however conditionally, we might be helped to take care of ourselves’’. [ , p ]. thus the ethical ideal is manifest in habits and practices as well as in aspirations and goals. health care anal you should not have let yourself go, but more than this, that it was a bad thing to do and you should work to address your failure. appearance then becomes a proxy for, and intimation of, character and value: thinness and grooming shows competence and efficiency, and scruffiness and dishevelment reveal inner turmoil or distress, and not dressing appropriately is a failure of respect (for the self or others). such judgements are routinely and constantly made, read directly from appearance, and are moral. effectively they are character assessments of virtues and vices. and just as we regard success as virtuous, shame and disgust attach to failure. further, like other ethical ideals, the beauty ideal purports to deliver the goods of the good life: material goods, relational goods and lifestyle goods. essentially the message is that if you conform to the beauty ideal, become better (thinner, firmer, smoother, younger) you will be rewarded with these goods: ‘‘that we’re desperate to be seen as fit and energetic and young and attractive makes sense when we are told on so many tacit and overt levels that we will find neither work nor sexual partners without these attributes; moreover, we are fated to lose both if we don’t retain at least the superficial vestiges of the original assets’’.[ , p ] while the evidence is somewhat contested there is significant empirical evidence which suggests that beauty does deliver at least some of the goods of the good life. the beautiful, for the most part, do better than those who are not beautiful; and although the differential is not dramatic nor is it negligible [ ]. to illustrate consider a few statistics. a recent large uk study suggested that tall men and slim women are relatively significantly better paid than those who are not. this was reported in the popular media, somewhat dramatically, as: men earn £ a year for every . inches; and women genetically predicted to be two stone heavier are ‘‘losing out’’ by £ a year [ ]. even if we regard the causal genetic claims with some suspicion (especially when it comes to weight which is strongly linked to socio-economic factors and to possible discrimination and bias, something which the researchers themselves note), being tall as a man and being thin as a woman is likely to lead to some material advantage. hamermesh draws the evidence from many empirical studies on this together and concludes that there is a ‘‘ or % premium for good looking workers’’ [ , p ] and a greater difference between unattractive and attractive. however, even if approximating the beauty ideal does deliver some of the goods of the good life, striving for the ideal is important, even if it is not attained (and does not deliver any material goods), and even if it is unattainable. recognising that the beauty ideal drives and influences behaviour—irrespective of the goods delivered— narratives of ‘‘shame’’ appear across beauty practices; fat-shaming being the most obvious example, but also when it comes to botched surgery, visible body hair, and aging. this account fits well with the ‘‘ought self’’ and suggests that there are parallels between this psychological understanding and accounts of the self under the beauty ideal as an ethical ideal. using uk biobank data of , participants, researchers aimed to study the causal effects of difference on stature and bmi against measures of economic status. it found that short stature and higher bmi were ‘‘observationally associated with several measures of lower socioeconomic status’’ [ ]. hamermesh presents a case from many studies that there is a beauty premium and an ugly penalty. for men this is % difference in earnings between attractive men and unattractive men, and % between attractive women and unattractive women. [ , p ]. health care anal helps us understand why it is such a powerful ethical ideal. the beauty ideal promises the possibility of perfection, or at least improvement: the perfect self remains beyond and in the future, an ideal to approximate, a possibility to be strived for and aspired to, and to be worked at. that it is unattainable does little to reduce the power of the ideal or our commitment to it. being perfectly good, or humble, are equally unattainable, but yet ideals which have been striven for in many contexts. understanding the power of ideals goes some way to explaining why, even when we know images are re-touched, we continue to judge ourselves against them and wish to attain the ideal they promise. the perfect image on the page feeds into our imaginings of the perfect ideal we are seeking to embody. like other ethical ideals, the beauty ideal not only holds out a promise of perfection (whether understood as being perfect, or simply becoming better, normal or improved), but also offers daily habits and practices to help us attain it and by which to structure our lives. thus, not only does it provide a value framework, but dictates tasks, skills and knowledge: to be good you must engage in daily practices (do a good turn every day); to be beautiful you must also engage in daily practices (those of routine maintenance, from hair removal to exercise). as such, like other ethical ideals it provides both long-term goals and mundane techniques which together structure and give meaning to day-to-day existence. by both promising goods and sanctioning failure, the beauty ideal engenders commitment from those who fall under it. it is this emotional commitment and investment in the ideal (manifested in the extent to which we judge ourselves and others by it) that helps to explain why images which present us with instances of the perfect ideal do not lose their power simply because we know they are digitally re- touched. our imaginings of our perfect—or improved or better or good enough— self, the end point of the beauty ideal for which we are striving, has very little to do with what is actually achievable or likely to be achieved. indeed, as we age the possibility of attaining the beauty ideal becomes ever less likely, but this does not mean that we reject the ideal or stop engaging in beauty practices. as technological interventions become more normalised and more accessible, so it becomes possible to attain some aspects of the beauty ideal, into middle and old age and increasingly pressures to conform to the beauty ideal, which once stopped or lessened at marriage or the menopause, now continue. consequently as we age and fall further from the ideal we may feel more pressure to engage, rather than less. conclusion in sum then, there are both psychological and philosophical accounts which offer some explanation for the initially surprising conclusion that drawing attention to digitally altered images may not, as one might expect and hope, reduce the aspiration to attain contemporary beauty ideals (to be thin, shapely and youthful). we are not claiming that from this we should conclude that there are no forms of contrary to some previous assumptions it may be that pressure to conform to beauty ideals is not a preserve of the young but extends into middle and old age. health care anal intervention with regard to media literacy which might be effective in altering beauty ideals, for instance, some suggest that a greater diversity of models of beauty might widen the beauty ideals to which we aspire. however, we are suggesting that beauty ideals cannot be easily challenged by such interventions. beauty ideals are culturally constructed and are carriers of meaning and value; accordingly if they are to be challenged, the extent of their ethical nature, and the way in which individuals actually make use of images for their own imaginings, needs to be recognised. acknowledgments we would like to acknowledge ahrc funding of the ‘changing requirements of beauty network’, the leverhulme trust, for major research fellowship funding, and birmingham university for hosting beauty demands (http://www.birmingham.ac.uk/generic/beauty/index.aspx). funding this study was funded by the arts and humanities research council (grant number ah/ l x/ ). compliance with ethical standards conflict of interest the authors declare that they have no conflict of interest. open access this article is distributed under the terms of the creative commons attribution . international license (http://creativecommons.org/licenses/by/ . /), which permits unrestricted use, dis- tribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. references . bird, e. l., halliwell, e., diedrichs, p., & harcourt, d. 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( ). what works in secondary schools? a systematic review of classroom-based body image programs. body image, , – . health care anal http://dx.doi.org/ . /bmj.i altered images: understanding the influence of unrealistic images and beauty aspirations abstract introduction digital images and body image revealing the unreal ideals, comparisons and ourselves beauty as an ethical ideal conclusion acknowledgments references shibboleth authentication request if your browser does not continue automatically, click () ar x iv : . v [ he p- ex ] ju n desy- - charm, beauty and top at hera o. behnke, a. geiser, m. lisovyi∗, desy, hamburg, germany ∗ now at physikalisches institut, universität heidelberg, heidelberg, germany june , abstract results on open charm and beauty production and on the search for top production in high- energy electron-proton collisions at hera are reviewed. this includes a discussion of relevant theoretical aspects, a summary of the available measurements and measurement techniques, and their impact on improved understanding of qcd and its parameters, such as parton density func- tions and charm- and beauty-quark masses. the impact of these results on measurements at the lhc and elsewhere is also addressed. contents introduction theory of heavy-flavour production at hera . hera kinematic variables and phase space . . . . . . . . . . . . . . . . . . . . . . . . . . perturbative qcd calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . heavy-quark production at hera in “leading order” . . . . . . . . . . . . . . . . . . . . quark-mass definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . the zero-mass variable-flavour-number scheme . . . . . . . . . . . . . . . . . . . . . . . . the massive fixed-flavour-number scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . the general-mass variable-flavour-number scheme . . . . . . . . . . . . . . . . . . . . . . proton structure functions in dis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . qed corrections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . fragmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . choice of renormalisation scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . the hera collider and experiments . hera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . h and zeus detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . event reconstruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . http://arxiv.org/abs/ . v charm and beauty detection at hera . charm tagging using full reconstruction of charm hadrons. . . . . . . . . . . . . . . . . . heavy-flavour tagging with lepton + prel t . . . . . . . . . . . . . . . . . . . . . . . . . . . charm and beauty with inclusive lifetime tagging . . . . . . . . . . . . . . . . . . . . . . charm and beauty with double tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . search for single top-quark production charm photoproduction . d∗ inclusive measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . charm total cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d∗ single-differential cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . . d∗ double-differential cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . inclusive measurements using other tagging methods . . . . . . . . . . . . . . . . . . . . studies with a d∗ and one other hard parton . . . . . . . . . . . . . . . . . . . . . . . . . parton-parton-correlation studies in charm-tagged events . . . . . . . . . . . . . . . . . . . xobsγ studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . azimuthal correlations ∆φ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . study of hard-scattering angle cos θ∗ . . . . . . . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . beauty photoproduction . total cross section for beauty production . . . . . . . . . . . . . . . . . . . . . . . . . . . single-differential cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . measurements of bb̄ and jet-jet correlations . . . . . . . . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . charm and beauty production in dis . production mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . single-differential cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . double-differential cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . proton structure functions and reduced cross sections . . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . measurement of qcd parameters, proton structure, and impact on lhc and other experiments . measurement of charm fragmentation functions and fragmentation fractions . . . . . . . . . charm fragmentation function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . charm fragmentation fractions and ratios . . . . . . . . . . . . . . . . . . . . . . measurement of parton density functions . . . . . . . . . . . . . . . . . . . . . . . . . . . proton flavour composition and w/z/h production at lhc . . . . . . . . . . . . . . . . measurements of the charm-quark mass and its running . . . . . . . . . . . . . . . . . . . measurement of the beauty-quark mass and its running . . . . . . . . . . . . . . . . . . . summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . summary and outlook introduction hera was the first and so far only high energy electron -proton collider. the production of heavy-quark final states in deeply inelastic scattering (dis) and photoproduction (γp) from ep interactions at hera (fig. ) originally was [ ] and still is (this review) one of the main topics of interest of hera-related physics, and of quantum chromodynamics (qcd) in general. (a) (b) figure : (a) the dominant production process for charm and beauty quarks in ep collisions at hera, the boson-gluon fusion (bgf) reaction. (b) the simplest quark-parton-model diagram for deeply inelastic scattering on a light quark. a quark is defined to be “heavy” if its mass is significantly larger than the qcd scale parameter Λqcd ∼ mev. the heavy quarks kinematically accessible at hera are the charm and beauty quarks, which are the main topic of this review. at the time of the proposal of the hera collider and experiments in the ’s [ ], a search for the top quark was one of the major goals [ ]. this influenced parts of the detector design: if at all, top quarks would be produced boosted into the proton direction, and top-quark mass reconstruction from hadronic final states would profit from an excellent hadronic energy resolution. as we know today, top-quark pair production was out of the kinematic reach of the hera collider. single top-quark production is kinematically possible, but strongly suppressed by standard model couplings. this allows the search for non-standard model top-production processes which will be covered in section . charm production at hera, in particular in deeply inelastic scattering, was realised from very early on to be of particular interest for the understanding of qcd [ , ]. up to one third of the hera cross section is expected to originate from processes with charm quarks in the final state: assuming “democratic” contributions from all quark flavours, which is a reasonable assumption at very high momentum transfers, this fraction f(c) can be approximated by the ratio of photon couplings in fig. , which are proportional to the square of the charges qq, q = u, d, s, c, b of the kinematically accessible quark flavours: f(c) ∼ q c q d + q u + q s + q c + q b = ≃ . , ( ) while a similar approximation for beauty yields f(b) ∼ ≃ . . in general, the impact of beauty on inclusive cross sections at hera is thus smaller than the impact of charm. at momentum transfers large enough for these approximations to be meaningful, charm and beauty can be treated as an integral part of the “quark-antiquark sea” inside the proton (fig. ), similar to the throughout this document, the term “electron” includes positrons, unless explicitly stated otherwise. light quarks in fig. b, originating from the initial state splitting of virtual gluons. since the proton has no net charm and beauty flavour number, charm and beauty quarks in the proton can only arise in pairs of quarks and anti-quarks (fig. (a) and shaded part of fig. ). however, due to the large charm- and beauty-quark masses of about . gev and gev, respectively, such a pair is considerably heavier than the mass of the proton. from purely kinematic considerations, it can thus not exist as a “permanent” contribution to the proton in the low-energy limit. considerations of so-called “intrinsic charm” [ ] have been challenging this simple point of view. since there is no evidence for such a contribution from hera data [ ], this will not be pursued further in this review. thus, charm and beauty “in the proton”, as depicted in fig. , are always considered to be virtual, and to arise as fluctuations from the perturbative splitting of gluons inside the proton. this establishes heavy quark production as a primary probe of the gluon content of the proton. e+ p γ c, b figure : quark-parton-model view of heavy flavour production in ep collisions at hera. different approaches to the theoretical treatment of charm- and beauty-quark production at hera are discussed in section . all these treatments crucially make use of the fact that the heavy-quark mass acts as a kinematic cut-off parameter in most of the qcd processes in which heavy quarks occur. furthermore, the fact that the heavy-quark mass is “large” compared to the qcd scale Λqcd ∼ . gev allows the usage of this mass as a “hard scale” in qcd perturbation theory, appropriately taking into account quark mass effects in perturbative calculations (fig. ). on the other hand, the “smallness” in particular of the charm-quark mass with respect to other scales appearing in the perturbative expansion, such as the virtuality of the photon, q , or the transverse momentum of a jet or a quark, pt , can give rise to potentially large logarithmic corrections, e.g. of the form ∼ [αs ln(p t /m q)]n or ∼ [αs ln(q /m q)]n ( ) where n is the order of the logarithmic expansion, αs is the strong coupling constant, and mq, q=c,b is the heavy-quark mass. the size and treatment of these corrections is one of the issues to be investigated. during the lifetime of the hera collider, of order charm and beauty events should have been produced in the h and zeus detectors, of which o( %) have been recorded to tape via both inclusive and dedicated triggers. hera can thus truly be considered to be a charm factory. further- more, the fact that charm- and beauty-quark production at hera can be studied essentially over its complete kinematic range, from the cc̄- or bb̄-mass threshold up to squared momentum transfers of order gev , offers the opportunity to treat hera as a “qcd laboratory” to test the different possible theoretical approaches to heavy-quark production against experimental data. many such tests are presented in sections and . in particular, the charm-production measurements can be used to constrain important qcd pa- rameters, such as the charm-quark mass and its running, and has important consequences for the figure : possible hard scales in the boson-gluon-fusion process. for the explanation of the symbols see text. determination of other parameters like the qcd strong coupling constant, αs. the measurements can also be used to constrain the charm fragmentation parameters, to constrain the flavour composition of virtual quarks in the proton, and to determine or cross-check the gluon distribution inside the pro- ton. such measurements and results are discussed in section . finally, the hera charm results have a significant impact on measurements and theoretical predictions for many qcd-related processes at hadron colliders, such as the lhc. for instance, the resulting constraints on the flavour composition of quarks in the proton reduce the uncertainties of the lhc w- and z-production cross sections, and the constraints on the gluon content of the proton are an important ingredient for the determination of the higgs yukawa coupling to top quarks from the dominant gluon-gluon-fusion higgs-production process via an intermediate top quark loop. such cross-correlations are also discussed in detail in section . beauty production at hera (sections and ) offers further complementary insight into the the- oretical intricacies of heavy-flavour production in qcd. due to its higher mass (mb ∼ gev) and a correspondingly smaller value of the strong coupling constant, its perturbative qcd behaviour is some- what better than the one of charm. however, the beauty mass remains non-negligible over essentially the full accessible phase space of hera, and a large fraction of the cross section is close to the kine- matic bb̄-mass threshold. this offers a particularly sensitive handle on the treatment of mass effects in qcd but also requires a particularly careful treatment of these mass effects in order to obtain reliable predictions. finally, the coupling of the photon to b quarks is four times smaller than the coupling to charm quarks (eq. ( )), and the higher b-quark mass yields a strong kinematic suppression. therefore in practice, depending on the region of phase space probed, the b-production cross section at hera is about – orders of magnitude smaller than the cross section for charm production. this makes separation from the background and accumulation of a significant amount of statistics experimentally much more challenging. also, the experimental analyses of beauty are often not fully separable from those of charm production. one of the highlights is the measurement of the beauty-quark mass (section ). others are the measurement of the total beauty-production cross section at hera (section ), and the potential impact of hera measurements on b-quark-initiated production processes at the lhc (section ). last but not least, most of the results presented depend on a good understanding of the performance of the hera machine and the hera detectors, as well as on mastering the heavy-flavour detection techniques. unfortunately, only a small fraction of the original data can make it through the various event filtering and reconstruction stages. these aspects will be addressed in sections and . except for the shortest ones, each section will start with a brief introduction and close with a summary, such that a reader less interested in the details may decide to skip the reading of the more detailed parts of the section. some of the material in this review has been adapted from an earlier unpublished review [ ] of one of the authors. further complementary information, in particular on charmonium and bottomonium production or diffractive charm production, which are not covered by this review, is available elsewhere [ , , , , ]. the broader context of other physics topics can be explored in a more general review on collider physics at hera [ ]. theory of heavy-flavour production at hera this section describes the different theoretical approaches to charm and beauty cross-section predictions, which will be needed later in the discussion of • the monte-carlo (mc) based acceptance corrections for the data sets used to obtain cross sections; • the extrapolation of different measurements to a common phase space, such that they can be compared or combined; • the comparison of different theory predictions to the measured cross sections; • the parton-density fits including the heavy-flavour data; • the fits of the charm and beauty masses and their running. since there is a large overlap between the theoretical approaches for these different purposes they will be discusssed in a common framework in the following. . hera kinematic variables and phase space the measurements of heavy-quark production at hera have been restricted, for statistical reasons, to neutral current events (exchange of a neutral boson) and to the kinematic region of the negative four-momentum transfer squared q <∼ gev , where photon exchange dominates and z exchange can be neglected. figure illustrates the event kinematic variables for ep scattering with heavy-quark production via the boson (i.e. photon) gluon fusion process (see also fig. ). e(k) e(k’) γ(q) c, b xp c, b xgp p(p) x s q w γ p figure : illustration of event kinematic variables for ep scattering at hera with heavy-quark pro- duction via the boson-gluon-fusion process. the four-momenta of the incoming electron k, the outgoing electron k′ and the proton p can be used to define the following lorentz-invariant variables: s = (k + p) ( ) q = −q = −(k − k′) ( ) x = q p · q ( ) y = p · q p · k ( ) w γp = (p + q) ( ) here √ s is the centre-of-mass energy of the ep system and q is the photon virtuality. wγp is the centre-of-mass energy of the γ(∗)p system. in the simple quark parton model [ ] (qpm) the bjorken scaling variable x describes the proton momentum fraction carried by the scattered parton (figs. (b) and ). the inelasticity, y, gives the fraction of the electron energy taken by the photon in the proton rest frame. only three of these five kinematic variables are independent. neglecting the masses of the electron and the proton the following relations between these quantities hold: q = s · x · y ( ) w γp = y · s − q ( ) in the full qcd case this picture becomes more complicated, as illustrated in fig. , where the proton momentum fraction xg carried by the gluon does not coincide any longer with bjorken x. however, eqs. ( ) – ( ) remain mathematically valid. the ep scattering events are classified by the photon virtuality q . the regime of small q ≈ gev is called photoproduction (γp) and the regime q ∼> gev is called deeply inelastic scattering (dis). more details on inclusive dis results and proton structure can be found elsewhere [ , , , , ]. . perturbative qcd calculations in fixed-order perturbative qcd (pqcd) the calculation of any parton-level cross section in ep, γp, p̄p or pp collisions can be expressed as σ(ab) = ∫ dxadxbf a pa (xa, µa)f b pb (xb, µf )σ̂papb(xapa, xbpb, µa, µf , αs(µr)) ( ) where a = e, γ, p̄ or p is one incoming beam particle, and the other, b, is a proton. pa is a “parton” taken from a, e.g. the electron or photon itself (dis and real photons), a slightly virtual photon radiated from the electron (photoproduction), or a gluon or quark from the structure of a real photon or (anti)proton. pb is a parton taken from the proton, i.e. a gluon or quark. xa and xb represent the respective momentum fractions of these partons with respect to their “parent” momenta pa and pb. note that these correspond to bjorken x and y as defined in the previous section only in the case of the quark-parton-model approximation to deeply inelastic ep scattering, while they have a different meaning in other cases. for example, in fig. , the quantity xg (rather than x) corresponds to xb as defined in eq. ( ), while xa = y in the photoproduction interpretation, and xa = in the hard dis interpretation. fapa and f b pb are the probability density functions, or parton density functions (pdfs), which give the probability, e.g. in the fbpb case, to find a parton of type pb with momentum fraction xb in a proton. σ̂papb represents the cross section for the partonic hard scattering reaction. this is sometimes split into the so-called hard process, i.e. the part of the reaction with the highest momentum transfer, and so-called initial state (i.e. occurring before the hard process) or final state (i.e. occurring after the hard process) radiation (fig. ). part of the initial state radiation can also be absorbed into the parton density definition. three energy scales µa, µf and µr appear in the expansion given by eq. ( ), which is also called factorisation, because the cross section is separated into semi-independent factors. the renormalisation scale µr determines the scale at which the value of the strong coupling constant αs is evaluated, i.e. it is the reference point around which the perturbative taylor expansion of qcd and using the improved weizsäcker-williams approximation [ ] in the case of y. figure : example for the factorisation of heavy-flavour production in qcd into proton structure, photon structure, hard matrix element and fragmentation. matrix element (me) calculations is performed. if the expansion is done to all orders in αs, the result does not depend on the choice of this scale. after truncation of the series to finite order, the neglected higher-order corrections arising from the contribution of a particular subprocess are minimised if this scale is chosen to be close to the physical scale of the momentum transfer in this subprocess. since at high enough perturbative order there are always different subprocesses with differing physical scales (see e.g. figs. , ), no single scale choice can universally cover all such scales. the variation of the cross section with respect to a variation of the renormalisation scale is used to estimate the uncertainty due to the finite-order truncation of this perturbative series. some further aspects concerning the choice of this scale are discussed in section . . the factorisation scale µf = µb determines at which scale the proton pdfs are evaluated. by default, any initial state radiation (lower blob in fig. ) with a momentum transfer smaller than the factorisation scale will be absorbed into the (usually collinear) pdf definition. in contrast, any initial state radiation with a momentum transfer larger than this scale, and all final state radiation down to the fragmentation scale (see section . ), will be considered as part of the matrix element, with correct (noncollinear) kinematics. on one hand, the choice of a lower factorisation scale therefore gives a more detailed description of the initial state radiation kinematics at a given order. on the other hand, the explicit treatment of initial state qcd radiation in the matrix element “uses up” a power of αs that would otherwise have been available for a real radiation elsewhere in the process, or for a virtual correction. this effectively reduces the order of the calculation with respect to the case where the same radiation is absorbed into the pdf definition, and therefore reduces the overall accuracy of the calculation. empirically, choosing a factorisation scale equal to or at least similar to the renormalisation scale has been found to be a good compromise. the third scale, µa, is conceptually the same as µf in the p̄, p and resolved γ cases, and therefore taken to be equal to it, while in the electron and direct photon case it is the scale at which the electro- magnetic coupling α is evaluated for the electromagnetic part of the matrix element (see section . ). . heavy-quark production at hera in “leading order” in general, the terminology “leading order” (lo), next-to-leading order (nlo), etc. for a perturbative qcd expansion is not unique. it can either refer to a specific power of the strong coupling constant αs or to a specific number of loops in the perturbative expansion of the matrix elements and/or parton splitting functions contributing to a given process. in order to be precise, this additional information thus needs to be quoted explicitly. at leading ( -loop) order in qcd, as implemented in the form of tree-level → hard matrix elements in most monte carlo generators, charm and beauty production in ep collisions is dominated by boson-gluon fusion (fig. (a)), complemented by other diagrams (figs. (b-d)). since a cc̄ or bb̄ pair is being produced (collectively referred to as qq̄), there is a natural lower cut-off mq for the mass of the hadronic final state. (a) p γ b b (b) ( ) (d) (a) (b) p γ g b ( ) (d) (a) (b) ( ) p γ b g (d) γ p e b b (a) (b) ( ) (d) direct-γ resolved-γ (a) γg-fusion (b) hadron-like (c) excitation (d) excitation figure : beauty production processes in leading order ( loop) qcd as implemented e.g. in pythia [ ]. note that in (c) and (d) the “photon remnant” (arrow arising from the photon) contains a b̄ quark. in the so-called massless approach (zero-mass variable-flavour-number scheme, zmvfns), in which the heavy quark mass is set to for the computation of the matrix elements and kinematics, this natural cut-off is replaced by an artificial cut-off (“flavour threshold”) at q ∼ m q for deeply inelastic scattering, or pt ∼ mq for photoproduction. below this threshold, which is often applied at the level of the factorisation scale, the heavy-flavour production cross section is (unphysically) assumed to vanish. above this threshold, heavy quarks are assumed to occur as massless partons in the proton, like the u, d, and s quarks (figs. (b) and ). except for cases in which both final state charm quarks have large transverse momenta p t > µ f , the gluon splitting to qq̄ in fig. (a) is thus assumed to happen inside the proton, and to be part of the evolution of the parton density functions. the running of αs is calculated using flavours (u, d, s) below the renormalisation scale mc, using flavours (including charm) between mc and mb, and using flavours above the scale mb. this results in a quark-parton- model-like scattering of the electron off a heavy quark “in the proton” (fig. ), defining the concept of the heavy-quark pdf. in this picture the leading-order process is now an o(α s) process, while the boson-gluon-fusion graph (fig. (a), with both heavy quarks at high pt ) is treated as part of the o(αs) next-to-leading order corrections. this illustrates the partially ambigous meaning of terms like lo, nlo, etc., discussed at the start of this subsection. higher order corrections can be applied either by explicitly including them into the calculation of the matrix elements and/or splitting functions, or, if they are to be applied at tree level only, by adding an additional so-called parton shower step. in the latter case, also referred to as leading order plus leading log parton shower (lo+ps), the outgoing and incoming partons of the core “hard” matrix elements are evolved forward or backwards using splitting functions as they are applied during the pdf evolution. most mcs (e.g. pythia [ ], herwig [ ] and rapgap [ ]) use the standard dglap evolution, as implemented e.g. in jetset [ ] for this purpose. however, in contrast to the pdf evolution, finite transverse momenta are assigned to the partons. some mcs (e.g. ariadne [ ]) use a colour dipole model for this evolution, while others use bfkl [ ] or ccfm [ ] inspired so-called kt factorisation (e.g. cascade [ ]). in the context of such mcs, the first diagram in fig. is referred to as direct production or flavour creation, and the third and fourth are referred to as flavour excitation (in the photon). either the second only (e.g. pythia) or collectively the last three (e.g. herwig) are being referred to as resolved photon processes. the second can uniquely be referred to as a hadron-like resolved-photon process. for the explicit generation of heavy-flavour final states in such lo+ps mcs, the boson-gluon-fusion diagram (fig. (a)) is optionally treated using massive matrix elements, while for all other diagrams the massless treatment remains the only available option. . quark-mass definition the heavy-quark masses appear in theoretical qcd calculations in several ways. their physical defini- tion arises from their appearance as parameters in the qcd lagrangian. the exact value of the masses depends on the renormalisation scheme applied. in the ms scheme, the masses are defined as pertur- bative scale-dependent running parameters (ms running mass), similar to the running strong coupling constant. in the on-shell mass renormalisation scheme, the masses are defined as the poles of the quark propagator (pole mass), similar to the usual definition of the lepton masses. this is also the definition which one would naively expect to enter phase space calculations. however, since quarks do not exist as free particles, and since the definition of the propagator pole inevitably involves contributions from the nonperturbative region, the pole mass definition has an intrinsic uncertainty of order Λqcd [ ]. at next-to-leading (one loop) order in perturbation theory, the relation between the pole and running mass definitions can be expressed as [ ] mq(mq) = m pole q ( − αs(mq) π ), ( ) where the running mass has been expressed in terms of its value at “its own scale”. its scale dependence can be expressed as [ ] mq(µ) = mq(mq)( − αs(µ) π ln µ m q ), ( ) or alternatively as [ ] mq(µ) = mq(mq) ( αs(µ) π ) β ( αs(mq) π ) β , ( ) with β = . higher order expressions can also be found in the quoted references. at leading ( loop) order, the difference between the two definitions vanishes. finally, in the context of so-called massless schemes, the “mass” is defined as a kinematic cutoff parameter in certain parts of the theory calculations. the pole-mass definition has been used in most qcd calculations relevant for this review. in recent variants of the abkm [ ] and acot [ ] schemes, the ms-running-mass definition is used instead. the latter has the advantage of reducing the sensitivity of the cross sections to higher order corrections, and improving the theoretical precision of the mass definition [ ]. . the zero-mass variable-flavour-number scheme in its “nlo” variant, including one-loop virtual corrections (fig. )(b)), the zmvfns has been used for most nlo variable-flavour parton-density fits up to a few years ago, such as cteq m [ ], zeus-s [ ], h [ ], nnpdf . [ ]. (a) (b) (c) (d) figure : leading order (o(α s)) (a) and selection of next to leading order (o(α s)) (b)–(d) processes for heavy flavour production in dis in the massless scheme. for (b), only the interference term with (a) contributes at this order. one of its advantages is that e.g. next-to-leading-log (nll) resummation of terms proportional to log(q /m q) can be applied to all orders, avoiding the problem that such logs could spoil the convergence of the perturbation series at high momentum transfers. however, it is clear that this simplified approach can not give the correct answer for processes near the “flavour threshold”. this has been verified experimentally e.g. for the dis case [ ] (section . ). also, it was found that neglecting the charm mass in the cross section calculations used for the pdf extraction can result in untolerably large effects on theoretical predictions even at high scales, such as w and z production at the lhc [ ]. all more recent pdf approaches [ , , , , , , ] therefore include at least a partial explicit consideration of the charm mass in the matrix elements (sections . and . ). nevertheless, since higher orders are more easily calculable in this scheme, the massless approach can offer advantages e.g. in high-energy charm-photoproduction processes [ , ] in which the consideration of an extra order of αs in the final state allows a reduction of the theoretical uncertainty (section ). . the massive fixed-flavour-number scheme the fixed-flavour-number scheme (ffns) treats the heavy-quark masses explicitly and follows a rigourous quantum field theory ansatz. full nlo (one loop) calculations of heavy-flavour production in this scheme exist for dis [ , , , , , , , ], for photoproduction [ , , , ] and for hadroproduction [ ]. some partial nnlo (two-loop) calculations are also available [ , ]. in this scheme, heavy flavours are treated as massive at all scales, and never appear as an active flavour in the proton. in the case in which all heavy flavours are treated as massive, the number of light flavours in the pdfs is thus fixed to , and charm as well as beauty are always produced in the matrix element (fig. ). so-called flavour excitation processes (fig. (c,d)), which are often classified as leading order (o(αs)) qcd in partially massless mc approaches [ , , ] of charm or beauty production, appear as o(α s) nlo corrections in the fully massive approach (fig. ). there are several variants of the ffns for heavy-flavour production in dis (see e.g. remarks in appendix of [ ]). in one approach, here called ffns a, the αs evolution used together with the flavour pdfs is also restricted to flavours. thus, the small contribution from heavy flavour loops (fig. (a)) mrst [ ] is a notable early exception. (a) (b) (c) (d) (e) figure : leading order (a) and selection of next to leading order (b)–(e) processes for heavy flavour production at hera in the massive scheme. is either treated explicitly in the matrix elements (ffns a) [ ], or, somewhat incorrectly, neglected completely (ffns a′) [ , ]. in either variant, this leads to a lower effective value of αs than in the massless scheme when evolved to high reference scales, e.g. αs(mz). this is one of the consequences of the non-resummation of log(q /m q) terms, and is partially compensated e.g. by a conceptually larger gluon pdf. despite the conceptual disadvantage of not allowing all order resummation of mass logarithms, this scheme yields very reasonable agreement with charm and beauty data at hera up to the highest q and p t (sections – ). at hera energies, the numerical differences between schemes a and a′ are of order %, and therefore almost negligible compared to the current data precision. (a) (b) (c) figure : heavy flavour loop correction (a) and gluon splitting (b,c) processes in the massive scheme. the thick (thin) lines indicate heavy (light) flavours. in the ffns b approach , which was widely used in the early nineties [ , , , , ], the running of αs is calculated by incrementing the number of flavours when crossing a flavour threshold, like in the variable-flavour-number scheme. the class of logs corresponding to this running is thus resummed both in the αs and in the pdf evolution, and the “missing” heavy flavour log resummation is restricted to other cases like gluon splitting and vertex corrections in the matrix elements. this approach is possible since most of the loop and leg corrections which diverge in the massless case, but compensate each other to yield finite contributions, remain separately finite in the massive case. they can thus be separated. at one-loop order, the a and b approaches differ by the way a virtual heavy flavour correction in the bgf matrix element (fig. (a)) (which is missing in the a′ approach) is treated. the ffns b scheme conceptually yields a value of αs at high scales which is the same as the one from the variable-flavour approach, and is probably less sensitive to “missing logs” at very high scales than the ffns a approach. most nlo photoproduction [ ] and hadroproduction [ ] calculations, as well as elsewhere [ ] this is sometimes called the mixed flavour number scheme. for a discussion see [ ][ ]. a recent new variant of it [ ] is referred to as the “doped” scheme. the electroproduction code hvqdis [ ] have been originally designed to be used with the ffns b scheme. the a and b approaches both converge to the exact qcd result at infinite order if implemented consistently. the a′ scheme can not converge to the exact result since heavy flavour loop corrections are completely missing, but, as stated earlier, the practical consequences at hera energies are small. it can however serve as a useful ingredient to variable flavour number scheme calculations (section . ). there are also other differences. in the abkm approach, final state gluon splitting (fig. (b,c)) is conceptually treated as part of the light-flavour contribution, while it is treated as part of heavy flavour production in many others [ , , , ] (see section . ), as well as in the measured cross sections, since it can hardly be distinguished experimentally. this difference is small [ ] in most regions of phase space, but might need to be accounted for when comparing data and theory. finally, ffns calculations in dis are currently available in leading order (o(αs)), or nlo (o(α s)) [ , , ]. partial nnlo (two-loop, o(α s)) calculations also exist, based on a full calculation of the o(α s)log and the o(α s)log terms, and the leading term from threshold resummation for the o(α s) constant term [ ]. further nnlo corrections for the high scale limit [ ] have not yet been implemented in practice. actually, both the nlo and partial nnlo abkm heavy flavour calculations use the pdfs from their nnlo (two loop, o(α s) in the matrix elements) fit to the inclusive data [ ]. some of the differences between the calculations discussed in this section and in the next two sections are also summarised in table , using the example of reduced charm cross sections in dis. . the general-mass variable-flavour-number scheme an alternative to the fixed-flavour-number approach is given by the so-called general-mass variable- flavour-number schemes (gmvfns) [ , , , ]. in these schemes, charm production is treated in the ffns approach in the low-q region, where the mass effects are largest, and in the massless approach at very high scales, where the effect of resummation is most noticeable. at intermediate scales (in practice often at all scales above the “flavour threshold”), an interpolation is made between the two schemes, avoiding double-counting of common terms, while making a continous interpolation between differing terms. this scheme combines the advantages of the two previous schemes, while introducing some level of arbitrariness in the treatment of the interpolation. γ∗ c c c -cx( ) γ∗ c c x -c g c -c x γ∗ g - + figure : leading order ( -loop) diagrams for charm production in dis in the variable flavour number scheme: on the left the qpm diagram is shown, on the right the bgf diagram and in the middle the “subtraction diagram” [ ]. the vertex correction loop diagram (fig. (b)), which also contributes to this order in αs, is not shown. one of the most constrained schemes is the bmsn scheme [ ] used by the vfns approach of abkm [ ]. at nlo, it interpolates between o(α s) charm matrix elements in the ffns part using the abkm ffns scheme, and o(αs) matrix elements in the massless part. it has no tuneable parameters, and (currently) uses the pole-mass definition for the ffns part. in contrast to most other gmvfns schemes, the switch to a larger number of flavours should not be made at the “flavour threshold”, but at a scale which is high enough that additional semi-arbitrary kinematic correction terms are not required. in practice, the -flavour scheme is used for processes at hera energies, while the - or -flavour schemes are recommended for applications at the lhc. theory scheme ref. f (l) mc pdf massive / fl massless f αs(mz) scale def. [gev] (q ∼< m c) (q ≫ m c) (nf = ) mstw nlo rt standard [ ] f c (l) . (pole) o(α s) o(α s) o(αs) . q mstw nnlo o(α s) approx.-o(α s) o(α s) . mstw nlo (opt.) rt optimised [ ] o(α s) o(α s) o(αs) . mstw nnlo (opt.) o(α s) approx.-o(α s) o(α s) . herapdf . nlo rt standard [ ] f c (l) . (pole) o(α s) o(α s) o(αs) . q nnpdf . fonll a fonll a [ ] n.a. √ o(α s) o(αs) o(αs) . q nnpdf . fonll b fonll b f c (l) √ (pole) o(α s) o(α s) / o(αs) o(αs) nnpdf . fonll c fonll c f c (l) √ (pole) o(α s) o(α s) o(α s) ct nlo s-acot-χ [ ] n.a. . o(α s) o(αs) o(αs) . √ q + m c ct nnlo [ ] f cc̄ (l) . (pole) o(α s) o(α s) o(α s) abkm nlo ffns a [ ] f cc̄ (l) . (ms) o(α s) o(α s) - . √ q + m c abkm nnlo o(α s) approx.-o(α s) - hvqdis+zeus s ffns b [ ] f c (l) . (pole) o(α s) o(α s) - . √ q + m c table : selected calculations for reduced charm cross sections in dis from different theory groups as used in this review. the table shows the heavy flavour scheme used and the corresponding reference, the respective f (l) definition (section . ), the value and type of charm mass used (section . ), the order in αs of the pdf part and the massive and massless parts of the calculation (and of the massless part of fl, which, except for fonll b, is usually taken to be the same as for the massive part), the value of αs, the renormalisation and factorisation scale. the distinction between the two possible f (l) definitions is not applicable (n.a.) for o(αs) calculations, or in photo- or hadroproduction. usually, the order of the pdf part is used to define the label lo, nlo, or nnlo. the nlo version of the tr scheme [ ] combines the o(α s) charm matrix elements in the ffns a′ scheme with the o(αs) matrix elements of the massless scheme, requiring continuity of the physical observables in the threshold region. in this case the usage of the a′ scheme is fully appropriate, since the missing terms will be taken care of by the massless and interpolation terms. several variants exist for the interpolation, including the so-called standard scheme used e.g. in mstw [ ] and herapdf . [ ], and the optimised scheme preferred for more recent versions, since it avoids a kink in the q dependence of the cross section [ ]. both of these variants also exist in a partial nnlo approach [ ], including approximate o(α s) threshold resummation terms for the ffns part, and a full o(α s) nnlo calculation for the massless part. they all use the pole mass definition for the ffns part. the acot [ ] scheme, used by cteq [ ], also exists in several variants. at nlo, o(αs) (i.e. leading order) ffns matrix elements are interpolated to o(αs) (now nlo) massless matrix elements . due to the lo ffns treatment, there is no difference between the pole-mass and running-mass schemes. the interpolation is made in two variants: the s-acot approach [ ], and the acot-χ approach [ ]. the nnlo variant of ct [ ] uses both ffns and massless matrix elements at o(α s), in the s-acot scheme. the fonll scheme [ ] has variants. the fonll a approach, used by nnpdf . [ ] is equivalent [ ] to the cteq s-acot approach, and uses o(αs) ffns heavy-quark matrix elements at nlo. fonll b and c both use o(α s) ffns heavy-quark matrix elements. fonll b uses o(αs) matrix elements for light quarks, like mstw, while fonll c uses o(α s) matrix elements for light quarks like abkm. however, they differ from the latter in the way they treat the interpolation terms. the fonll c scheme is also similar [ ] to the cteq s-acot nnlo scheme. a full nnlo version of the fonll a approach also exists [ , ]. final state gluon splitting is not included in the charm cross-section predictions for any of these schemes. the abm group uses the bsmn approach [ ] to generate a gmvfns scheme out of their ffns -, - and -flavour pdfs [ ]. for photoproduction, a gmvfns calculation [ ] exists for single inclusive cross sections. all gmvfns variants use the variable-flavour approach for the running of αs. although the mass is unambigously defined in the massive part of the calculation (usually the pole mass), the partial arbitrariness in the treatment of the interpolation terms (fig. ) prevents a clean interpretation of the charm and beauty quark masses in terms of a single renormalisation scheme. therefore, in contrast to the pure ffns treatment, the charm mass appearing in vfns schemes can be treated as an effective mass parameter [ ]. we will use the symbols mc and mb for these effective mass parameters. alternatively, the presence of the interpolation terms can be included as an additional uncertainty on the respective mass definition [ ]. . proton structure functions in dis in analogy to the inclusive neutral current dis cross section, the cross sections for heavy-quark pro- duction in dis can be expressed in terms of the heavy-quark contributions to the inclusive structure functions [ ] f , fl and f , denoted by f qq̄ , f qq̄ l and f qq̄ (q = c, b): dσqq̄(e±p) dx dq = πα x q ( ( + ( − y) ) f qq̄ − y f qq̄ l ∓ x ( − ( − y) ) f qq̄ ) , ( ) where α is the electromagnetic coupling constant. the structure function f qq̄ makes the dominant contribution to the neutral current scattering in the kinematic regime accessible at hera. f qq̄ contains also referred to as rt the fact that similar matrix elements are denoted by different labels concerning their effective order in different context is very confusing, but unavoidable due to different definitions of the truncation of the perturbative qcd series. contributions only from γz interference and z exchange, therefore for the region q ≪ m z, which was studied at hera, this contribution is suppressed and can be neglected. the longitudinal heavy-quark structure function f qq̄ l parametrises the contribution from coupling to the longitudinally polarised photons. the contribution of f qq̄ l to the ep cross section is suppressed for y ≪ , but can be up to a few percent in the kinematic region of the heavy-quark measurements at hera and thus can not be neglected. for both electron and positron beams, neglecting the f qq̄ contribution, the reduced heavy-quark cross section, σ qq̄ red , is defined as σ qq̄ red (x, q ) = dσqq̄(e±p) dx dq · x q πα y+ = f qq̄ − y y+ f qq̄ l , ( ) where y± = ( ± ( − y) ). thus, σqq̄red and f qq̄ only differ by a small f qq̄ l correction at high y [ ]. in the quark-parton model, the structure functions depend on q only and can be directly related to the parton density functions. in the qcd case, and in particular for heavy flavour production, this correlation is strongly diluted, and the structure functions depend on both x and q . more information on the general case can be found e.g. in [ , ]. using the example of the charm case [ ], the above definition of f cc̄ (l)(x, q ) (also denoted as f̃c [ ] or fc,si [ ]) is suited for measurements in which charm is explicitly detected. it differs from what is sometimes used in theoretical calculations in which f c (l)(x, q ) [ , , ] is defined as the contribution to the inclusive f (l)(x, q ) in which the virtual photon couples directly to a c or c̄ quark. the latter excludes contributions from final state gluon splitting to a cc̄ pair in events where the photon couples directly to a light quark, and contributions from events in which the photon is replaced by a gluon from a hadron-like resolved photon. as shown in table of [ ], the gluon splitting contribution is expected to be small enough to allow a reasonable comparison of the experimental results to theoretical predictions using this definition. the hadron-like resolved photon contribution is expected to be heavily suppressed at high q , but might not be completely negligible in the low q region. from the point of view of pqcd it appears at o(α s) and it is neglected in all theoretical dis calculations used in this review. . qed corrections in addition to the different qcd schemes discussed above, predictions of charm production can also differ through their treatment of qed corrections. some of these corrections, e.g. collinear photon radiation from the initial state electron before the hard interaction (fig. ) can actually be large (of order α ln q max m e ), and can influence the definition of the q , x and y variables [ ]. for photoproduction calculations, the improved weizsäcker-williams approximation [ ] can be used to parametrise the photon spectrum arising from the incoming electron. for acceptance corrections (and partially for visible cross sections), predictions including full lo qed radiative corrections, as implemented e.g. in heracles [ ], are used. for more sophisticated purposes, an nlo version of these corrections is available in the hector package [ ]. at the level of the dis structure functions or σr it is customary to translate the measured cross sections to so-called born-level cross sections, i.e. cross sections in which all qed corrections have been removed, to ease comparison of the data with pure qcd predictions. there is one potential exception: the fine structure “constant” α can be used in two different ways. • as a genuine atomic scale constant α = . , i.e. all virtual qed corrections are removed, too; • as running α in the ms scheme, i.e. the respective relevant virtual corrections are kept, and a typical value for hera kinematics is then α ≃ [ ]. e+ p γ γ c, b c, b√ αs g figure : bgf diagram with initial state photon radiation. the difference between these two approaches in qed has some remote similarity to the difference between the ffns a and b schemes in perturbative qcd (section . ), treating all quarks and leptons as “heavy” with respect to the atomic scale. . fragmentation equation ( ) allows one to make predictions of heavy-quark production with partons in the final state. however, cross sections are measured and reported mostly in terms of heavy-flavour hadrons, leptons from their decay, or collimated jets of hadrons. therefore such predictions have to be supplemented with a fragmentation or hadronisation model. in analogy to e+e− collisions [ ], the factorised cross section for the production of a heavy-quark hadron h as a function of transverse momentum pht can be written as: dσh dpht (pht ) = ∫ dp q t p q t dσq dp q t (p q t , µf) d h q ( pht p q t , µf) · f(q → h), ( ) where σq(x, µf) is the production cross section for heavy quarks (eq. ( )), d h q is the fragmentation function, µf is the fragmentation scale and f(q → h) in the fragmentation fraction. the latter is defined as the probability of the given hadron h to originate from the heavy quark q. the fragmentation function defines the probability for the final-state hadron to carry the fraction z = pht /p q t of the heavy- quark momentum. the fragmentation function is defined similarly to the pdfs. in the “massless” approximation, it is defined at a starting scale and has to be evolved to a characteristic scale µf of the process using perturbative qcd. in the massive fixed flavour approach, this evolution can be conceptually absorbed into the pole mass definition. fragmentation fractions as well as the starting parametrisation of the fragmentation function can not be calculated perturbatively. thus they have to be extracted from data. comprehensive phe- nomenological analyses of the charm and beauty fragmentation functions in e+e− collisions have been performed [ , , ]. while the qcd evolution is process-dependent, the non-perturbative ingredients of the fragmentation model are assumed to be universal . comparing measurements from hera and results from e+e− colliders one can test this universality. however, the tools that are available for o(α s) fixed-order calculations of the heavy-quark produc- tion cross sections in ep collisions, which are mostly used for exclusive final states, do not comprise a the non-perturbative fragmentation function is universal only if it is accompanied by appropriate evolution. perturbative component of the fragmentation function. therefore, an “independent” non-perturbative fragmentation function dnp(z) is used in conjunction with the parton-level cross sections. the para- metric forms of the independent fragmentation functions most commonly used at hera are due to peterson [ ]: dnp(z) ∝ z( − /z − ε/( − z)) , kartvelishvili [ ]: dnp(z) ∝ zα( − z) and to the bowler modification of the symmetric lund [ ] parametrisation: dnp(z) ∝ /z +rqbm q ( − z)a exp(−b(m h + p t )/z), where ǫ, α, a, b and rq are free parameters that depend on the heavy-flavour hadron species and have to be extracted from data. since no qcd evolution is applied, the corresponding parameters might be scale- and process-dependent. the recent gmvfns nlo predictions for charm photoproduction [ ] incorporate a perturbative fragmentation function and have been tested against data (section ). . choice of renormalisation scale for many cross-section predictions the dominant contribution to the theoretical uncertainty arises from the variation of the renormalisation and factorisation scales by a factor around some suitably chosen default scale. such a variation is intended to reflect the uncertainty due to uncalculated higher orders. it might therefore be useful to consider some phenomenological aspects of these scale choices as considered in a mini-review on beauty production at hera and elsewhere [ ], focusing in particular on the choice of the renormalisation scale. ideally, in a qcd calculation to all orders, the result of the perturbative expansion does not depend on the choice of this scale. in practice, a dependence arises from the truncation of the perturbative series. since this is an artefact of the truncation, rather than a physical effect, the optimal scale can not be “measured” from the data. thus, it must be obtained phenomenologically. traditionally, there have been several options to choose the “optimal” scale, e.g. • the “natural” scale of the process. this is usually taken to be the transverse energy, et , of the jet for jet measurements, the mass, m, of a heavy particle for the total production cross section of this particle, or the combination √ m + p t for differential cross sections of such a particle. often, this is the only option considered. the choice of this natural scale is based on common sense, and on the hope that this will minimise the occurrance of large logs of the kind described above, for the central hard process. however, higher order subprocesses such as additional gluon radiation often occur at significantly smaller scales, such that this choice might not always be optimal. • the principle of fastest apparent convergence (fac) [ ]. the only way to reliably evaluate uncalculated higher orders is to actually do the higher-order calculation. unfortunately, this is often not possible. instead, one could hope that a scale choice which makes the leading-order prediction identical to the next-to-leading-order one would also minimise the nnlo corrections. this principle, which can be found in many qcd textbooks, can not be proven. however, recent actual nnlo calculations might indicate that it works phenomenologically after all (see below). • the principle of minimal sensitivity (pms) [ ]. the idea is that when the derivative of the cross section with respect to the nlo scale variation vanishes, the nnlo corrections will presumably µr / mh . . σ(pp → h+x) [pb] mh = gev lo nlo n lo n loapprox figure : scale dependence of the total cross section for beauty production at hera-b [ ] (left) and for higgs production at the lhc [ ] (right). also be small. again, there is no proof that this textbook principle should work, but actual nnlo calculations might indicate that it does (see below). to illustrate these principles, consider two examples. first, the prediction for the total cross section for beauty production at hera-b [ ] (fig. ). the natural scale for this case is the b-quark mass, µ = mb, and all scales are expressed as a fraction of this reference scale. inspecting fig. , one finds that both the pms and fac principles, applied to the nlo prediction and to the comparison with lo (nlo stability), would yield an optimal scale of about half the natural scale. the same conclusion would be obtained by using the nlo+nll prediction, including resummation, and comparing it to either the lo or the nlo prediction (nlo+nll stability). second, the prediction for higgs production at the lhc [ ] (fig. ). the reference scale is now the higgs mass (µ = mh). however, inspecting the behaviour of the lo and nlo predictions, neither the fac nor the pms principle would yield a useful result in this case, since the two predictions do not cross, and the nlo prediction does not have a maximaum or minimum. this situation occurs rather frequently, and is also true for b production at hera. fortunately, in the case of higgs production, the nnlo and even approximate nnnlo predictions have actually been calculated (fig ). applying the fac and pms prescriptions to these instead (nnlo stability), again a scale significantly lower than the default scale would be favoured. this might indicate that choosing a scale which is smaller than the default one makes sense even if the fac and pms principles do not yield useful values at nlo. beyond these examples, a more general study is needed to phenomenologically validate this approach. to avoid additional complications arising from a multiple-scale problem caused by e.g. the scale q at hera or the scale mz at lep, the study was limited to cross sections for photoproduction at hera, or hadroproduction at fixed-target energies, the tevatron, and lhc. the somewhat arbitrary selection of processes includes beauty production at the spp̄s [ , ], the tevatron [ ], and hera-b [ ], top production at the tevatron [ , ], direct photon production at fixed target [ ], z [ ] and higgs [ ] production at the lhc, jets at hera [ ] and at the tevatron [ ]. this selection is obviously not complete, and many further calculations, in particular nnlo calculations, have been achieved since this study [ ] was originally made. however, it is not biased in the sense that all processes that were originally considered were included, and none were discarded. clearly, a quantitative update of this study would be useful, but was not yet done. qualitatively, all newer predictions which the authors have been made aware of either confirm this conclusion, or at least do not significantly contradict it. in each case the natural scale as defined above was used as a reference. in addition, wherever figure : summary of optimised scales derived as described in the text. possible, the optimal scales from both the fac and pms principles, evaluated at nlo (nlo stability), nlo+nll (nlo+nll stability), and/or nnlo/nnnlo (nnlo stability) were evaluated separately. figure shows the result of this evaluation. each crossing point, maximum, or minimum in fig. yields one entry into this figure, and similarly for all the other processes. the conclusion is that the fac and pms principles tend to favour scales which are around - % of the natural scale. amazingly, this seems to be independent of whether these principles are applied at nlo, nlo+nll, or nnlo level. for the jet [ ] or b-jet [ ] cross sections at the tevatron, it has in part already become customary to use half the natural scale as the central scale. using the natural scale as the default and varying it by a factor two, which is the choice adopted for most data/theory comparisons, covers only about half the entries, while the other half lies entirely below this range. instead, using half the natural scale as the default and varying it by a factor two, thus still including the natural scale in the variation, covers about % of all the entries. this yields the following conclusions. • obviously, whenever an nnlo calculation is available, it should be used. • whenever possible, a dedicated scale study should be made for each process for the kinematic range in question. although there is no proof that the fac and pms principles should work, in practice they seem to give self-consistent and almost universal answers for processes at fixed target energies, hera, the tevatron, and the lhc. • in the absence of either of the above, the default scale should be chosen to be half the natural scale, rather than the natural scale, in particular before claiming a discrepancy between data and theory. empirically, this should enhance the chance that the nnlo calculation, when it becomes available, will actually lie within the quoted error band. to evaluate uncertainties, the customary variation of the central scale by a factor up and down remains unaffected by this choice. the latter principle has already been applied to a few of the results covered in this review. of course, choosing the natural scale as the central value, which is still the default for most calculations (or making any other reasonable scale choice), is perfectly legitimate and should also describe the data within the theoretical uncertainties. however, if it does not, it might be useful to consider alternative choices as discussed above before claiming evidence for the failure of qcd, and hence for new physics. further complementary information, in particular on the related theory aspects, is available else- where [ ]. . summary the theory of heavy flavour production in the framework of perturbative qcd, and in particular the occurrence of different possibilities to treat the heavy quark masses in the pdf, matrix element and fragmentation parts of the calculation, introduces a significant level of complexity into the corresponding qcd calculations, in addition to the usual scheme and scale choices. confronting different choices with data can be helpful to understand the effects of different ways to truncate the perturbative series. the majority of the available mc calculations for the analysis of hera data is based on leading order (plus parton shower) approaches, combining a massive approach for the core boson-gluon fusion process, and the massless approach for tree level higher order corrections. it will be demonstrated in the later chapters that this is fully adequate for acceptance corrections. for comparisons of the measured differential cross sections with qcd predictions, a next-to-leading order massive approach (fixed flavour scheme) is the state of the art. in some cases massless calculations are still in use, e.g. to facilitate the perturbative treatment of fragmentation, or to implement resummation of some of the logarithms arising when the mass competes with other hard scales occurring in a process. in particular for the prediction of the inclusive heavy flavour structure functions in dis, a variety of so-called general-mass variable-flavour schemes are available, merging massive calculations at low scales with massless calculations at high scales. these are particularly useful for the extraction of pdfs over very large ranges in energy scale. partial nnlo calculations are also available for such inclusive quantities, both in the fixed and variable flavour number schemes. due to the absence of extra semi-arbitrary parameters, the fixed flavour number scheme is particularly well suited for the extraction of qcd parameters like the heavy quark masses. in general, qed corrections are nonnegligible, and available both at leading and next-to-leading order. since α is much smaller than αs, the leading order precision is often sufficient. several compet- ing fragmentation models are in use, and the perturbative treatment of fragmentation in the massive approach is still in its infancy. since higher order corrections are large, the uncertainties reflected by the qcd scale variations are often dominant. until full nnlo calculations become available, a careful consideration of the choice of these scales can be helpful to avoid premature conclusions concerning potential discrepancies between the theory predictions and the data. the hera collider and experiments in this section, the hera collider, the h and zeus experiments, as well as the reconstruction of the data from these experiments will be briefly described, with focus on aspects relevant for heavy flavour production. . hera hera (german: hadron-elektron-ring-anlage) was the first and so far the only electron–proton collider. it was located at desy in hamburg, germany. the circumference of the hera ring (see fig. ) was . km. the accelerator was in operation from to . electrons or positrons and figure : a schematic view of the hera ep storage rings with the h and zeus experiments protons were accelerated in two separate rings to final energies of . − . gev and gev ( gev before ), respectively, leading to a centre-of-mass energy of √ s = − gev ( gev before ). both beams were stored in bunches. the bunch-crossing rate was mhz. electrons and protons collided in two interaction regions, where the h and zeus detectors were located. in the years – the hera collider was upgraded to increase the instantaneous luminosity. at the same time a number of upgrades of the h and zeus detectors were put in place, as described below. therefore, the data taking was subdivided into two phases: “hera i” and “hera ii” corre- sponding to the data taking periods – and – , respectively. in , a few months were dedicated to data taking at lower centre-of-mass energies. . h and zeus detectors the h and zeus detectors were typical modern multi-purpose collider experiments and are described in detail in [ , , , ]. figure visualises the layout of the h and zeus detectors . due to significantly higher energy of the protons there was more detector hardware installed in the direction the right-handed cartesian coordinate system used at h and zeus has the z axis pointing in the nominal proton beam direction, referred to as the “forward direction”, and the x axis pointing towards the centre of hera. its coordinate e± p ❄ ❈ ❈ ❈ ❈ ❈❲ lar calor. ❄ ❄ central jet ch. ✁ ✁ ✁ ✁ ✁ ✁ ✁✕ forward tracker ✄ ✄ ✄ ✄ ✄ ✄✎ ❄ spacal zr view e± p ✻ mvd � � � � � � ��✒ ctd ❄ ✑ ✑ ✑ ✑ ✑ ✑ ✑✑✰ ❍ ❍ ❍ ❍ ❍ ❍ ❍ ❍ ❍ ❍❥ cal ✘✘ ✘✘ ✘✘ ✘✘✿ stt figure : the rz-view of the tracking system and calorimeters of the h (top) and zeus (bottom) detectors. the layout of the central silicon tracker (cst) and the microvertex detector (mvd) are shown separately below. the electron beam enters from the left, while the proton beam enters from the right. h zeus silicon vertex detector: cst mvd # layers θ-coverage [ ◦, ◦] [ ◦, ◦] η-coverage [− . , . ] [− . , . ] σ(δ) ⊕ /pt µm ⊕ /pt µm drift chambers: ctd ctd θ-coverage [ ◦, ◦] [ ◦, ◦] η-coverage [− . , . ] [− . , . ] σ(pt )/pt . pt ⊕ . . pt ⊕ . ⊕ . /pt calorimeters: lar cal (hera i) θ-coverage [ ◦, ◦] [ . ◦, . ◦] η-coverage [− . , . ] [− . , . ] el.-magn. σ(e)/e . / √ e ⊕ . . / √ e hadronic σ(e)/e . / √ e ⊕ . . / √ e spacal θ-coverage [ ◦, ◦] η-coverage [− . , − . ] el.-magn. σ(e)/e . / √ e ⊕ . muon systems: cmd r/b/fmuon+bac θ-coverage [ ◦, ◦] [ ◦, ◦] η-coverage [− . , . ] [− . , . ] table : parameters and performance of the h and zeus subdetectors which are relevant for the heavy-flavour physics analyses presented in this review. the benchmarking is shown for the hera ii run conditions, unless stated otherwise. transverse momenta pt and energies e are in units of gev. δ is the transverse distance of closest approach of tracks to the nominal vertex. σ(δ) is the resolution of δ, averaged over the azimuthal distribution of tracks. of the outgoing proton beam. the figures show the key parts of the main detectors that were used for tagging and reconstruction of heavy-flavour events. some of the most important benchmarks of the h and zeus detectors, such as polar angle coverage and momentum, the energy resolution and the resolution of the impact parameter δ , are listed in table . in the following the main components of the h and zeus detectors are discussed with emphasis on the advantages of the respective designs: tracking chambers: tracks from charged particles were reconstructed based on the position mea- surements in the large central drift chambers. the pulse height on the sense wires was used to measure the energy loss in the detector medium, de/dx. the de/dx measurements were used for par- ticle identification, distinguishing between electrons, pions, kaons and protons in a limited momentum origin is at the nominal center of the respective detector, which coincided with the nominal interaction point in the hera i period. the pseudorapidity is defined as η = − ln (tan(θ/ )), where the polar angle, θ, is measured with respect to the proton beam direction. the x-y- or r-φ-plane is also denoted as the transverse plane. also referred to as the transverse distance of closest approach to the nominal vertex range. the important differences between h and zeus are: • the h tracking detector comprised two chambers cjc and cjc [ ] while the zeus ctd [ ] was a single chamber that was divided into nine superlayers. • for zeus a superconducting coil surrounded the tracking detectors and provides a magnetic field of . tesla. this is considerably higher than the . tesla delivered by the h superconducting coil, situated outside the calorimeter. in both experiments the magnetic field within the tracking system was parallel to the z axis. • four of the nine superlayers of the zeus chambers were equipped with stereo wires, which were tilted ∼ ◦ with respect to the beam axis. this provided z-measurement points for tracks with a resolution of ∼ . mm. at h the sense wires were strung parallel to the beam axis and the track z-position measurement was obtained by the division of the charges recorded at both wire ends, yielding a moderate resolution of a few centimetres. two additional z-drift-chambers were installed to provide for each track a few z-measurement points with typically µm resolution. in the forward region h and zeus have installed a forward tracking detector (ftd) [ ] and a straw tube tracker (stt) [ ], respectively, that are based on drift-chambers. their main purpose is to extend the polar angular coverage to angles smaller than ◦, outside the acceptance of the central drift chambers. however, for both experiments these detectors have not been used for momentum reconstruction due to a large amount of dead material in front of them. nevertheless, the forward detectors were partially used in the pattern recognition. vertex-detector: the central silicon tracker (cst) [ ] and the micro vertex detector (mvd) [ ] were located in the heart of the h and zeus experiments. the mvd was installed only for the hera ii data taking. the vertex detectors allowed the determination of trajectories of charged particles in the vicinity of the primary vertex. the achieved precision was sufficient to resolve vertices from secondary decays. this is essential for the tagging of weakly-decaying heavy-flavour hadrons with a typical lifetime cτ ≃ – µm. the cst (mvd) consisted of two (three) cm ( cm) long concentric cylindrical layers of double- sided silicon-strip detectors the innermost layer of the cst and mvd was located at . mm and ∼ mm, respectively. the most important benchmarking parameters are given in table . the following intrinsic hit resolutions were achieved: ∼ µm for the cst and ∼ µm for the mvd. the cst had a somewhat better average transverse impact parameter resolution mainly due to less material, hence less multiple scattering, but was essentially restricted to track reconstruction in the transverse plane. the mvd contained four wheels of double-sided silicon-strip detectors in the forward region that extended the polar-angle coverage from ◦ to ◦. furthermore, it allowed d standalone pattern recognition. at h the cst was supplemented with the forward and backward strip detectors, fst and bst, that extended the polar-angle coverage of cst to [ ◦, ◦]. however, these were not used in h heavy-flavour analyses. calorimeters: the tracking detectors were surrounded by calorimeter systems, which covered almost the full solid angle. their main tasks were to identify and measure the scattered electron, to reconstruct the hadronic final state (e.g. jets) and photons and to separate electrons from hadrons. at h a fine- grain liquid-argon (lar) sandwich calorimeter [ , ] was installed in the central and forward region. it was supplemented in the backward region with the lead-scintillating fibre calorimeter spacal [ , ]. in the zeus detector the solenoid was surrounded by a high-resolution compensating uranium– scintillator calorimeter (cal) [ ]. the calorimeters had inner electromagnetic and outer hadronic sections. the electron and hadron energy scales of the calorimeters were known at the level of % and %, respectively. the calorimeters were calibrated from the data using kinematic constraints. overall, both calorimeter systems performed very well. additionally, for detection of very-low-q events, where the electron is scattered at a small angle, zeus installed the beampipe calorimeter (bpc) [ ]. this calorimeter was in operation in hera i and was located just . cm from the beam line. it allowed the extension of the phase-space coverage to . < q < . gev electron taggers: both h and zeus were equipped with special detectors, called electron taggers, which were able to detect electrons scattered at very small angles. especially during the hera i period, these could be used to explicitly identify photoproduction events in specific ranges of w . muon systems: to identify muons both experiments installed large arrays of limited-streamer tubes [ , ] inside and outside the magnetic return yoke (not shown), which covered a wide range in polar an- gle and measured muons efficiently for transverse momenta above ∼ gev, with significant partial acceptance also at lower pt . the return yoke of the zeus detector was also equipped with drift tubes providing complementary muon identification and serving as a backing calorimeter (bac). a forward muon system completed the coverage of the tracking detectors. the h detector had a similar muon coverage, including the usage of the liquid argon calorimeter as a tracking calorimeter. luminosity measurement: in both experiments the luminosity was measured using the photon bremsstrahlung process ep → eγp. the photons were detected by dedicated detectors [ , ] about m away from the interaction points in the e-beam direction. in addition, h also used the spacal to measure the large-angle qed compton scattering [ ]. the ultimate precision of the luminosity measurement by h (zeus) is . % ( . %) for the hera ii period and . % ( . %) for the hera i period. trigger and readout system: both h [ ] and zeus [ , ] have used a multi-level trigger system to select interesting ep events online and to suppress background from beam–gas interactions. the h trigger system consisted of two hardware layers and one software filter. it was supplemented for the hera ii period by an additional track trigger. the zeus trigger was based on one hardware and two software levels. the first two levels mostly operated with the energy sums in the calorimeter, timing and limited tracking information. on the third level a complete reconstruction of the event is performed, using a simplified version of the offline reconstruction software, to select more sophisticated objects like jets, tracks and even d-meson candidates. the triggers reduced the rate from the nominal hera bunch-crossing rate mhz to the storage rate ∼ hz. while the topology of dis events allowed triggering on the scattered electron inclusively already at the first level of the trigger chain, triggering on heavy-flavour photoproduction was more challenging and required reconstruction of leptons, tracks, hadronic activity in the calorimeter or even explicitly charm hadrons. both experiments had capabilities to include limited tracking information already at the first trigger level, for instance on the number of tracks and the fraction which originates from the ep interaction vertex. . event reconstruction various heavy-flavour tagging techniques (see section ) exploit different measured quantities, like tracks, vertices, energy-flow objects, jets and muons. the reconstruction of these quantities is described in the following: figure : helix parameterisation in the track-fit procedure. the initial parametrisation at the point of closest approach as well as effects of multiple scattering are shown. tracking: tracks were reconstructed combining hits from the central tracking chambers, silicon-strip detectors and forward/backward trackers for high |η|. in both experiments tracks were parametrised with a helix defined by parameters (fig. shows the r-φ-view): the curvature κ = q/r, which is the signed inverse radius, d , the dca distance of closest approach in the xy plane, φ , the azimuth angle, z , the distance of closest approach along the z axis, and the polar angle θ . to account for multiple scattering and energy loss in the material along the track trajectory and for inhomogeneities of the magnetic field, the track parametrisation was refined in a track-refit process based on a broken-lines algorithm [ ] in h and a kalman filter [ ] in zeus. additionally, the parameterisation of all tracks that were fitted to the primary or to a secondary vertex (see below) was further improved by a track refit using the vertex position as a constraint. analyses that aimed at the best tracking precision used tracks with typically |η| < . . this coverage corresponds to the region where efficiencies and resolutions are high and well known. performance benchmarking for the two tracking systems is shown in table . at low momenta, the de/dx measurement for each track allowed the separation of pions, kaons and protons, while at high momenta electron/hadron separation was possible to some degree. vertexing: reconstructed tracks were used as an input for the primary vertex in each event. in addition, if silicon-strip information was available, the time-averaged mean xy position of the ep interaction region, the beam spot, was used to further confine the position of the primary vertex in the event. the beam spot was measured by the experiments as a function of time for each ∼ events. the beam spot size in the transverse plane was measured to be σx = µm and σy = µm in h hera i data, σx = µm and σy = µm in h hera ii data, and σx = µm and σy = µm in zeus hera ii data. the beam-spot size along the z axis was much larger, σz ∼ cm, and therefore was not used as a constraint. in h the vertex fitting was performed in the xy plane , while zeus did a full vertex fit in xy z. nevertheless, both experiments used only the xy projections of decays in heavy-flavour analyses due to superior resolution. in addition, in the context of some zeus heavy-flavour analyses, selected tracks were removed from the primary vertex fit and the fit was re-done. combinations of such tracks were fitted to a displaced secondary vertex that was associated with a decay of a heavy-flavour hadron. procedures similar to those used in the primary-vertex fit are used to fit the secondary vertices as well. alternatively, combinations of impact parameters of several tracks were used in h . secondary vertices give an important handle: • to test the hypothesis that selected tracks originate from a decay of the same particle by evaluation of the χ of the secondary vertex; an iterative procedure to determine the z position of the primary vertex was used. for obvious reasons, no beamspot constraint is used. • to evaluate the flight distance of that particle, which is related to the particle cτ. this will play an essential role (together with the track impact parameter) in the heavy-flavour lifetime tagging (cf. section ). electron reconstruction: electron identification was needed to reconstruct dis events as well as to measure semi-leptonic decays of beauty and charm quarks. electrons were separated from hadrons using the shape of clusters in the calorimeter and de/dx information from the central drift chambers. a typical phase-space coverage for electrons in a beauty-production measurement in the semi-leptonic electron decay channel was pt > gev (pt > . gev) and − < η < . (|η| < . ) for the h (zeus) measurements. muon reconstruction: muons were identified by combining information from the tracking systems, calorimeters and muon chambers. for pt > . − gev (p > gev) the information from the muon chambers was exploited and the fraction of hadrons which were misidentified as muons was typically less than %. for momenta – gev isolated muons can be efficiently identified in the calorimeters, using “minimum ionising particle” (mip) signatures, which however leads to reduced purity. the efficiency to identify high momentum isolated muons in the h and zeus muon systems was % and % [ ], respectively. the wide coverage of the muon chambers allowed the extension of the phase space of the measure- ments up to − . < η < . . hadronic system: energy flow objects (efos) were used in both experiments to reconstruct the hadronic final state [ , ]. these objects were based on a combination of information from the calorimeter and the tracking system optimising energy resolution. track information is superior for low-energy efos, while the calorimeter measurement is preferred at high energy as well as to measure neutral particles. jets at hera have been reconstructed with the inclusive kt clustering algorithm [ , ] . the r parameter was set to r = , which is larger than the values used typically at pp and pp̄ experiments ( . – . ), since at hera jets with relatively low transverse momenta were analysed. the chosen jet algorithm is infrared and collinear safe to all orders in perturbation theory. it was checked [ ] that at hera the kt , anti-kt [ ] and siscone [ ] algorithms produce very similar measurement results and that the precision of nlo qcd calculations for the anti-kt algorithm is very similar to that of the kt algorithm. the final precision of the jet energy scale uncertainty of the h and zeus calorimeters was – % (see [ ] for a recent review of jet results from hera). . summary hera was the first and so far only high energy ep collider. the results discussed in this review were obtained with the h and zeus detector in two different running periods, denoted “hera i” and “hera ii”. the main detector parts relevant for the detection and reconstruction of heavy flavour events were the electromagnetic part of the calorimeters for the reconstruction of the scattered electron (if detectable), the calorimeters and tracking systems for the reconstruction of the decay products of heavy flavoured particles, and the muon systems for the detection of semileptonic decay final states. mostly in the longitudinally-invariant mode with the massless pt and massive et recombination schemes [ ] in the h and zeus experiments, respectively charm and beauty detection at hera the large charm- and beauty-quark masses result in kinematical suppression of their production com- pared to the light-flavour cross sections. therefore, special techniques have to be employed to separate charm and beauty “signal” from the dominating light-flavour “background”. these techniques utilise distinct properties of the charm and beauty hadrons (see fig. for illustration): ) (mev)π)-m(ksππm(k c o m b in a tio n s / . m e v - zeus pb < gev < w < gev, q )| < . and+(d*η) > . gev, | +(d* t p )| > . (dη) < . gev or | (d t p + backgroundmodgauss wrong charge background background ±) = +(d*addn zeus / cm δ - . . e n tr ie s h / cm δ - . . e n tr ie s h data b c uds sum / cm δ - . . e n tr ie s / cm δ - . . e n tr ie s h data b c uds sum / cm δ - . . e n tr ie s (a) p rel t [ gev ] e n tr ie s data bb − cc − uds sum h q < gev figure : overview of tagging methods for heavy-flavour events. each method is accompanied by an illustrative distribution [ , , ]. . flavour tagging. the tagging of the quark flavour is done either by full reconstruction of decays of heavy-flavoured hadrons or by lepton tagging from the semi-leptonic decays of those hadrons. the former was used at hera only for charm tagging, since low production rates and small branching ratios for useful decays led to insufficient statistics for fully-reconstructed beauty hadrons. the latter was mostly used for beauty tagging, since b-hadron decays produce leptons with sufficiently high momenta for efficient identification in the detectors. . lifetime tagging. this method exploits the relatively long lifetimes of weakly-decaying heavy- flavour hadrons through the reconstruction of tracks with large impact parameter δ or displaced secondary vertices. in addition, the information about the flight direction, extracted from either the track, hadron or jet momentum, can be used to construct a signed impact parameter or a signed decay length (see later). this is a powerful tool to separate charm and beauty from light-flavour events, in which tracks mostly originate from the primary vertex. . mass tagging. the tagging using the mass of the heavy quark or meson is performed either explicitly by a full reconstruction of the mass from all decay products (also see flavour tagging), by a partial reconstruction via the mass of a jet or of all tracks at a secondary vertex, or indirectly by measuring the relative transverse momentum of a particle with respect to the axis of the associated jet, prelt . the latter was mostly used to separate beauty events from production of other flavours, since the large quark mass produces large prelt values. the above methods are all based on measuring the decay particles of one heavy quark (single tag). several methods can be combined to increase the purity at the cost of statistics. both heavy quarks (double tag) in an event can be tagged, by applying one method to tag one heavy quark and another (or the same) for the other heavy quark. this allows a more detailed study of the heavy-quark production mechanisms, but the double tagging efficiencies are low. in the following the different tagging methods are discussed in more detail with emphasis on the advantages and disadvantages of each method. . charm tagging using full reconstruction of charm hadrons. most of the hera charm results have been made using the golden decay channel d∗+ → d π+s → (k−π+)π+s (see fig. ) . occasionally, also the d → k−π+π−π+ decay channel was used to increase statistics. due to the small energy release in the decay d∗+ → d π+s (m(d∗+) − m(d ) − m(π+) ≈ mev) the phase space for combinatorial background is suppressed, and the resolution for the d∗ − d mass difference is strongly enhanced, providing an excellent signal to background ratio. this also leads to a small momentum of the produced pion, which is often called the “slow” pion, πs. the capability of a detector to measure very-low-momentum tracks defines the accessible region of pt (πs) and therefore the phase space of the d∗ : a typical pt (πs) > . gev restriction leads to pt (d ∗) > . gev. for some analyses the pt (d ∗) cut was raised to suppress the combinatorial background, which rises at low pt (cf. fig. (a) and (b)). for the signal extraction, the observable ∆m = m(k−π+π+s ) − m(k−π+) was chosen. the number of signal events is determined either by counting the number of events in the peak region after subtracting the combinatorial background, which is estimated from the ∆m distribution of “wrong charge” k+π+π−s combinations, by fitting the spectrum with a gaussian-like shape for the signal and a phenomenological function for the background, or by a combination of these two methods. besides the d∗ golden decay channel, the d → k−π+, d+ → k−π+π+, d+s → k+k−π+ and Λ+c → pk−π+ decays of charm hadrons were used to tag charm in the events. these charm hadrons feature much larger background (see fig. (c) for an example of a d+ measurement). however, a lifetime tag can be added, exploiting the relatively large values cτ ∼ – µm for the weakly- decaying charm hadrons. the decay length is reconstructed by fitting a displaced secondary vertex to selected tracks of decay products (see section . for more details). this combined approach allowed to significantly reduce combinatorial background, most noticeably for the d+ that has the largest lifetime (cf. fig. (c) and (d)), to a level that is still somewhat worse than but comparable to the d∗ . nevertheless, due to the low boost, lifetime tagging is inefficient in the phase space pt (d) < m(d) that is also not accessible with d∗ ’s. in this region it is beneficial to study particular decay channels with neutral strange hadrons k s or Λ, for example d + → k sπ+. the h and zeus experiments achieved a similarly good signal mass-peak resolution for charm hadrons. note that the distributions in fig. can not be compared directly due to different kinematic regions. in summary, the advantages (+) and disadvantages (−) of full hadron reconstruction are: throughout the paper the d∗+ is mostly referred to as d∗ . the full reconstruction of d∗ ’s at hera was impossible since the resulting decay photon or π could not be reliably measured. ) [gev]π) - m(kππm(k . . . . . . . . e n tr ie s / . m e v h data wc comb. sig+bg fit d*± h (a) pt(d ∗) > . gev ) (mev)π)-m(ksππm(k c o m b in a tio n s / . m e v - zeus pb < gev < w < gev, q )| < . and+(d*η) > . gev, | +(d* t p )| > . (dη) < . gev or | (d t p + backgroundmodgauss wrong charge background background ±) = +(d*addn zeus (b) zeus . . m(kππ) (gev) c o m b in a tio n s p e r m e v zeus - reflections subtracted gaussmod + backgr. < w < gev, q < gev pt(d ±) > . gev, |η(d±)| < . n(d±) = ± (c) ) (mev)ππm(k c o m b in a tio n s / . m e v zeus - zeus pb < gev < w < gev, q )| < . + (dη) > . gev, | +(d t p + backgroundsumgauss background ±) = +n(d (d) figure : full reconstruction of mass spectra for charm mesons in the data. the reconstructed mass difference ∆m for d∗ (a) [ ] and (b) [ ] and the d+ mass (c) [ ] and (d) [ ] are shown. + the full reconstruction allows an accurate determination of the momentum of the charm hadron, which is correlated with the kinematics of the charm quark and can be used to study the frag- mentation process. + an excellent signal to background ratio of ∼ : can be achieved using the d∗ golden decay channel or the reconstruction of other weakly-decaying mesons including a lifetime tag (fig. ). + the combinatorial background can be parametrised with an empirical function and does not depend on monte carlo simulations of the light-flavour background. + the signal mass peak is a clear signature which can be used in the online filtering of events to reduce the trigger rates. this requires the usage of advanced tracking information in the trigger logic. − the typical probabilities for a charm quark to hadronise into a specific d meson are ≈ . – . and the branching ratios, br, for the commonly used decay channels are ≈ . – . ; thus, only ∼ – % of all c quarks can be tagged. the kinematic and geometric acceptances reduce the visible fraction even further, in particular in the case of the additional use of lifetime tagging, which reduces the detection efficiency by a factor ∼ – . therefore, only a very small fraction of charm quarks can be tagged with the full reconstruction method. - . - . . . . impact parameter δ [ cm ] e n tr ie s data bb − cc − uds sum h q < gev p rel t [ gev ] e n tr ie s data bb − cc − uds sum h q < gev figure : distributions of the signed impact parameter δ of the muon track (left) and the transverse muon momentum prelt relative to the axis of the associated jet (right) for the photoproduction event sample of the h beauty analysis [ ]. the data (dots) are compared to monte carlo predictions (solid line). separate contributions of events arising from b-quark (dashed line), c-quarks (dotted line) and the light-quark (dash-dotted line) production are shown. . heavy-flavour tagging with lepton + prelt a well established method to identify beauty quarks is to select a muon with high transverse mo- mentum of typically above . − gev from semileptonic b-quark decay, which is associated to a jet that represents the beauty quark and consists of the muon and further final-state particles. the back- ground to this signature is composed of charm production with a genuine muon from semi-leptonic decays and of light-flavour events with a hadron misidentified as a muon (mainly due to in-flight π+ and k+ decays and hadronic energy leakage). to separate beauty from the background contributions for a single tag, the prelt observable is used which, due to the large beauty-quark mass, extends to much larger values than for the other sources. additionally, a lifetime tag can be added by reconstructing the signed impact parameter, δ, of the muon track (see section . for more details). this further improves beauty separation and also allows charm-event tagging, since long-lived heavy-flavour hadrons lead to larger δ values than in light-flavour events. figure shows the distribution of both variables. the beauty component has a distinct shape in both that allows one to disentangle it from the others. the fractions of light-flavour, charm and beauty events in the data are determined from template fits to the discriminating variables extracting template shapes from monte carlo simulations with data-driven corrections. in some analyses also the missing energy in the detector, which is associated with the undetected neutrino, was considered to improve charm/light-flavour separation. a similar technique can be followed using electrons. this allows going down to pt (e) > gev, however the available η region is narrower than for muons (see section ) and the lepton signature is more complex. in summary, the advantages (+) and disadvantages (−) of the use of semileptonic hadron decays are: also charm, but less efficiently. + the relatively large branching ratio br(b → ℓx) ∼ % [ ], which includes b → cx → ℓx and other cascade decays, provides a reasonable tagging efficiency for b quarks. + muon tagging extends the phase space of heavy-quark measurements, due to additional coverage outside of the polar acceptance of the central tracking systems. thus measurements of beauty production in the forward and backward regions are possible with muons. + semi-isolated leptons provide a clean experimental signature for the trigger system. they allow one to efficiently select beauty events suppressing charm and light-flavour production by pt (ℓ) cuts. − the requirement of a jet associated with the lepton in order to use prelt or lifetime tagging cuts into the low-pt phase space of the b quarks. − the usage of semi-leptonic tagging for charm studies is very complicated due to weak separation power. . charm and beauty with inclusive lifetime tagging the aforementioned tagging methods suffer from the fact that only a fraction of the charm or beauty quark decays ends up in the selected final state. this can be avoided by using an inclusive tagging method, based on the long lifetime of charm and beauty quarks: cτc ≃ – µm and cτb ≃ µm. this approach relies on silicon-strip detectors to accurately measure the track parametrisation in the vicinity of the interaction vertex (see section ). therefore, it was not yet available in zeus for the hera i data set and was pioneered at hera by the h collaboration. lifetime tagging can be based either on impact parameters of individual tracks or on decay lengths of displaced secondary vertices fitted to selected tracks. both techniques typically use tracks with transverse momenta pt > . gev to limit multiple scattering and hits in at least two layers of the vertex detectors. the lifetime tagging is often applied based on information in the transverse xy plane, since the profile of the interaction region and also the detector layouts do not allow for sufficiently high resolution of the tracks in the coordinate along the beam line. the impact parameter distribution allows the separation of long-lived heavy-flavour hadrons from short-lived light-flavour hadrons. figure illustrates how the signed impact parameter is defined with respect to the jet to which the track is associated. a positive sign is assigned to δ if the angle α between the jet axis and the line joining the primary vertex and the point of closest approach is less than ◦, and a negative sign otherwise. figure (left) shows the distribution of the signed impact parameter of muon tracks in the data and the flavour decomposition in the monte carlo simulations. the light-flavour component is characterised by a very small lifetime and the observed symmetric distribution is caused by the detector resolution. in contrast, the charm and beauty contributions exhibit a pronounced tail for large positive δ values. to further improve the separation power, the impact parameter significance s = δ/σ(δ) can be used. this allows the rejection of candidates with an insignificant measurement of the impact parameter. in the vertexing approach, a displaced secondary vertex is fitted to all tracks that are associated to a selected jet . the distance between the primary and the secondary vertex is sensitive to the lifetime of the hadron that initiated the jet. similar to the impact parameter, the flight direction can be introduced to form the signed decay length as used by h or the projected decay length in zeus. the former is defined similarly to the signed impact parameter, whereas the latter is defined as l = (~rsv − ~rpv) · ~p |~p | here, a jet can be either a real jet in the detector or a set of tracks corresponding to a d-meson candidate. jet axis track jet axis track figure : illustration of the positive and negative signed impact parameter (left). a reconstructed vertex for a heavy-flavour decay shown in the xy plane [ ] (right). the errors of the primary and secondary vertex positions (shaded ellipses) have been blown up by a factor of for illustrative purposes. (see fig. ), i.e. the projection of the vector from the primary to the secondary vertex on the jet momentum. finally, the ratio of such a quantity over its uncertainty, s, provides the optimal sepa- ration power. a kinematic reconstruction of the mass of the vertex that corresponds to the jet, mvtx, provides an additional handle on flavour separation, since contributions of light-flavours, charm and beauty are expected to populate predominantly the small (mvtx ≪ md), medium (mvtx <∼ md) and large (md < mvtx <∼ mb) mass domains, respectively. figure illustrates the lifetime tagging with secondary vetrices. the light-flavour contribution is symmetric around zero, while the charm and beauty components exhibit a pronounced asymmetry in the region of large decay-length significance. the beauty contribution dominates at large vertex mass and large significance values. lifetime tagging can be used either as an add-on to other tagging techniques (as described before) or as a separate tagging tool. the dominant background is light-flavour production, which is symmetric in the signed impact parameter significance or the projected decay length significance. the contents of the negative bins of the significance distribution can be subtracted from the contents of the corresponding positive bins, yielding a subtracted significance distribution. this way, the contribution from light- flavour quarks is minimised. the h collaboration has chosen to use a combination of the signed impact parameter significance of individual tracks and the signed decay-length significance to tag heavy-flavour production. events are exclusively categorised according to the number of tracks in the event. the significances s , s and s are defined as the significance of the track with the highest, second highest and the third highest absolute significance, respectively. the s and s significance distributions (fig. ) are used for events with one and two selected tracks, respectively. for events with three or a higher number of tracks various sensitive variables including s , s , s and the signed decay-length significance of the reconstructed secondary vertex are combined using an artificial neural network. in general, s has a better discrimination between light- and heavy-flavour contributions than s , since the chance of reconstructing two high significance tracks is further reduced for light-flavour. the neural network (fig. (c)) provides separation between c and b events. for all distributions the negative part was subtracted from the positive one to minimise the light-flavour component and a least-squares fit was performed simultaneously to all three distribution. the charm and residual light-flavour components were found to be very strongly anti-correlated in such fits (typical correlation coefficients are clc < − . ), while the s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s zeus < . gevvtx < m < gevvtx . < m < gevvtx < m vtxno restriction on m - zeus pb monte carlo lf charm beauty figure : distributions of the decay-length significance for different ranges of the vertex mass mvtx. [ ]. the data (points) are compared to monte carlo simulations (filled area). the individual contri- butions of beauty (dashed line), charm (dotted line) and light flavours (solid line) are shown. correlation with beauty is weaker due to the more distinct shape of the beauty distributions (ccb ≈ − . and clb ≈ . ). also alternative approaches to lifetime tagging have been studied, but were found to be more sensitive to systematics from track resolution and efficiency. the zeus collaboration, on the other hand, made inclusive charm and beauty measurements ex- ploiting vertexing for tagging. the projected decay-length significance and the reconstructed mass of the fitted secondary vertices (fig. ) were used as discriminating variables. a χ fit of the subtracted significance distribution was performed in the three vertex-mass bins simultaneously. the correlation pattern between components was found to be very similar to the one in the h analyses. figure shows the subtracted significance distributions. with optimised cuts after subtraction one can get sam- ples with very high charm and beauty enrichment of roughly % and %, respectively. such selection resulted in ∼ charm and ∼ beauty events after negative subtraction in the recent zeus measurement [ ]. in summary, the advantages (+) and disadvantages (−) of this inclusive lifetime tagging method are: + this tagging method gives access to the largest statistics due to the inclusive selection of the final state. + the technique provides strong discrimination power and is often combined with other tagging methods. + with the applied track minimal transverse momentum cut of . gev one obtains a good accep- tance for low heavy-quark momenta, which is of high importance for measuring the charm and beauty contributions to inclusive ep scattering. the additional typical jet cut e jet t > gev ∼ mb retains a high acceptance for beauty production near threshold. − the total achieved effective signal to background ratio is typically not better than : for both charm and beauty. this can be estimated from the numbers of charm and beauty events in the positive subtracted significance spectra, which effectively represent the numbers of tagged events, track significance s ) ) - n ( -s n ( s track significance s ) ) - n ( -s n ( s h data total mc uds c b track significance s ) ) - n ( -s n ( s (a) track significance s ) ) - n ( -s n ( s track significance s ) ) - n ( -s n ( s h data total mc uds c b track significance s ) ) - n ( -s n ( s (b) nn output . . . . n ( n n o u tp u t) - n ( -n n o u tp u t) nn output . . . . n ( n n o u tp u t) - n ( -n n o u tp u t) h data total mc uds c b nn output . . . . n ( n n o u tp u t) - n ( -n n o u tp u t) (c) figure : the subtracted distributions of (a) s , (b) s and (c) the neural-network output [ ]. the beauty- (dashed line), charm- (dotted line) and light-flavour (dashed-dotted line) contributions are shown. and from the errors achieved for the charm and beauty components in the fit. − the method requires the track resolutions and efficiencies to be thoroughly scrutinised. − with the typical cuts on the jet transverse momentum one actually cuts strongly into the kinematic phase space for charm. a requirement of a jet with e jet t > gev corresponds to a cut p d t > . gev assuming that ∼ % of the quark transverse momentum is transfered to the d meson. . charm and beauty with double tagging the various heavy-flavour tagging methods outlined above can be combined, aiming towards tagging both heavy quarks in the event. at hera, d∗ µ combinations were used to tag both charm and beauty events, while a di-lepton tag was used for beauty only. the usage of two flavour tags significantly reduces the light-flavour background, which allows omitting any additional mass or lifetime tags. furthermore, it gives access to correlations between the quarks of heavy flavour pair. in the example of the photon-gluon fusion process, γg → cc̄ or bb̄, the two heavy quarks are produced back-to-back in the γg frame as illustrated in fig. for the beauty case. unlike-sign combinations such as µ+µ− or d∗+µ− can be produced from either the same or different b quarks, while like-sign combina- tions originate always from different b quarks (combination of b and c̄ decays + charged conjugate, or b −b̄ mixing). in charm events only oppositely-charged combinations are produced. in analyses using d∗ µ tags the charm and beauty components were separated based on the sign combination and the angular distance in azimuth. in charm events mostly back-to-back unlike-sign d∗ and µ are produced, while for beauty both like- and unlike-sign combinations are possible and more complicated angular distributions arise. the di-lepton analyses have also used the information about charge combination and angular separation between leptons, and additionally the mass of the lepton pair. in summary, the advantages (+) and disadvantages (−) of double tagging are: + for a large fraction of the events double tagging gives access to the kinematics of both heavy quarks. this information can be used to investigate the cc̄ and bb̄ production processes in detail. + since light flavours are efficiently suppressed by the requirement of two flavour tags, the leptons can be selected in transverse momentum down to ∼ gev with a reasonable purity. for beauty this gives access to much lower quark momenta than the lepton + prelt tag that was discussed in section . . light-flavour production is suppressed by d∗ reconstruction |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s zeus < . gevvtx < m < gevvtx . < m < gevvtx < m vtxno restriction on m - zeus pb monte carlo lf charm beauty figure : the subtracted distributions of the decay-length significance for different ranges of the vertex mass mvtx [ ]. the data (points) are compared to monte carlo simulations (filled area). individual contributions of beauty (dashed line), charm (dotted line) and light flavours (solid line) are shown. d* + − + _− _ figure : various possible ways to produce d∗ µ or a µµ pair from the decays of the b- and the b̄-quark produced in the photon gluon fusion process at hera. − the total tagging efficiency is very low. − the lepton tagging is well suited for the measurement of beauty production but has relatively small acceptance for charm, where, due to softer fragmentation, the leptons take a smaller fraction of the quark transverse momentum than in the beauty case. − due to their low pt , the correlation of the d∗ and the µ momenta with those of the parent quarks is not as good as for jets. . summary various heavy-flavour tagging methods have been used at hera. each of them has advantages and disadvantages, which results in different tags being optimal for different purposes. the most commonly used tags have been d∗ reconstruction and inclusive lifetime tags for charm and lepton + prelt and inclu- sive lifetime tags for beauty. whenever possible, a comparison between (and potentially a combination of) measurements performed with different techniques allows improved constraints on the measurements, due to cross-calibration of systematics of different nature for independent tags. often a combination of tags yields an increased purity of the heavy-flavour sample, at the cost of reduced efficiency and additional systematics. in general, the choice of the tagging method(s) is a trade-off between statistical and systematic uncertainties. search for single top-quark production already before the start of hera data taking, it became clear from the lower limits of order – gev on the top-quark mass obtained from p̄p collisions by the ua /ua [ ] and cdf [ ] collaborations, that top-quark pair production would probably be outside the kinematic reach of hera. this was confirmed by indirect constraints from lep [ ] and by the direct observation of the top quark at the tevatron at a mass of gev [ ]. single top quark production in the charged current reaction [ ] e+ + b → ν̄e + t (and its charged conjugate) remained kinematically possible, but the expected standard model cross section of less than fb [ ] is too small to be experimentally accessible. this is due to the fact that the occurrence of initial state b quarks is strongly suppressed at high x, since it would need to originate from the splitting of ultra-high-x gluons in the proton (in analogy to fig. ), which are known to be very rare [ ]. charged current reactions on light initial state quarks are strongly suppressed by the very small corresponding ckm matrix elements [ ]. if at all, single top quarks could thus be produced at hera only via a process beyond the standard model [ ]. one such process is the transition of a u quark into a t quark via a flavour-changing neutral current [ ] (fig. ) caused by non-standard model couplings of the photon or z boson. figure : feynman graph for anomalous single top production [ ]. this possibility was investigated in particular due to an excess observed by the h collaboration in the single isolated lepton + jets final state [ ], which was however not confirmed by a corresponding zeus analysis [ ], and greatly reduced in significance by a common analysis of the zeus and h data [ ]. γubr - - - u z b r - - excluded by zeus zeus - zeus . fb ,u(c)zγ u(c)→aleph t ,u(c)zγ u(c)→cdf t γ u→h t u(c)z→d t γubr - - - u z b r - - figure : limits on anomalous couplings for single top production, translated to branching fractions (br) for top decay into uz or uγ [ ]. no significant signal was observed. fig. shows the exclusion contours obtained by the h [ ] and zeus [ ] collaborations for the anomalous couplings to photons or z bosons for this process, translated to branching ratios for anomalous top quark decays. the h limit is a bit looser than the the one from zeus due to the small excess mentioned above. these limits are competitive with limits obtained from other colliders, also shown in fig. , and currently represent the best limit for the anomalous photon coupling. they can be improved further in future analyses using data from the lhc [ ]. single top quarks were also searched for in the full-hadronic top decay channel, with a similar sensitivity as for the lepton channel [ ]. however, the corresponding analysis was performed on the hera i data set only, so the resulting limit is no longer competititive. charm photoproduction the study of open charm- and beauty-production cross sections provides stringent tests of perturbative qcd from several perspectives. on one hand, the size of the charm- and beauty-quark masses ensures that for all such final states the production cross sections are in the perturbatively calculable regime, since mc, mb ≫ Λqcd. on the other hand, the qcd scales obtained from these masses compete with other potential scales like the quark tranverse momentum or, in the dis case, the virtuality of the exchanged photon (fig. ). the treatment of such a multi-scale problem is theoretically challenging and a comparison of different theoretical schemes to data can shed light on the strengths and weak- nesses of the respective perturbative approximations. furthermore, from the theoretical point of view, the presence of final-state heavy-flavour hadrons ensures that these processes will not interfere with corresponding final states involving only gluons and light quarks, and that they can thus be treated independently for each flavour. thus, in the following, charm and beauty production will be treated separately. in general, photoproduction processes have many similarities to corresponding processes in hadropro- duction, “simply” interchanging the incoming quasi-real photon with a quasi-real gluon. since the spp̄s and tevatron pp̄ colliders went into operation almost a decade before the hera collider, perturbative nlo qcd calculations have often first been obtained for hadroproduction, although the incoming pho- ton diagrams are somewhat easier to calculate. furthermore, since the virtuality of the incoming photon (q < gev ) is of the order of typical hadron masses or lower, the photon can have a hadron-like structure (“hadron-like resolved photon”, fig. b). thus, the cross sections get a contribution from the convolution of perturbative hadroproduction diagrams with this photon structure. this in turn com- plicates the photoproduction cross-section calculations. however, this hadron-like photon contribution is small (of order % or less) in the case of the treatment of heavy-flavour production in the massive scheme. an important variable for photoproduction analyses at hera is the event kinematic observable y, which represents the fraction of the electron energy entering the hard interaction (section . ). this variable can be reconstructed from the hadronic final state in the main detector (section ). an overview of all charm photoproduction measurements in h and zeus is given in table . . d∗ inclusive measurements despite the large loss in statistics through fragmentation fractions and branching ratios, it is clear from table that the very clean explicit reconstruction of d∗-meson final states offers the best effective signal sensitivity for charm photoproduction. . . charm total cross sections in the very first zeus [ ] and h [ ] measurements on open-charm production (entries and in table ) the inclusive d∗ results were extrapolated to obtain total charm-photoproduction cross sections. the results are shown in fig. (left) as a function of the photon-proton centre-of-mass energy wγp. measurements from fixed-target experiments from the pre-hera era are also shown. at hera, both wγp values and the observed cross sections are roughly one order of magnitude larger. the steep cross- section rise reflects the fact that with increasing wγp gluons with smaller and smaller proton momentum fractions are accessible for charm production via the photon-gluon-fusion process (fig. ). the data in fig. are compared to a massive scheme nlo prediction [ ], which is able to describe both the fixed-target data at lower wγp and the hera data at higher wγp. despite the large uncertainties, this demonstrated early on that the basic charm-production mechanism in photoproduction is at least reasonably well understood. no. analysis c-tag ref. exp. data l [pb− ] q [gev ] y particle pt [gev] η events effect. s:b bgfree events d∗ incl. kππs [ ] zeus . < [ . , . ] d ∗ > . [− . , . ] ± : . d∗ tagged kππs [ ] h . < . [ . , . ] d ∗ > . [− . , . ] ± : . incl. . < [ . , . ] ± : . d∗ incl. kππs [ ] zeus . < [ . , . ] d ∗ > [− . , . ] ± : . k ππs ± : . d∗ tagged kππs [ ] h - . < . [ . , . ] d ∗ > [− . , . ] ± n.a. - . < . [ . , . ] > . (ŷ(d∗)) ± n.a. d∗ incl. kππs [ ] zeus - < [ . , . ] d ∗ > [− . , . ] ± : . k ππs > ± : . d∗ + dijet kππs d∗ jet ( ) > > ( ) [− . , . ] [− . , . ] ± : . d* incl. kππs [ ] zeus - < [ . , . ] d ∗ [ . , ] [− . , . ] ± : . d∗ tagged kππs [ ] h - < . [ . , . ] d ∗ > [− . , . ] ± : . +jet jet > [− . , . ] ± : . +dijet jet ( ) > ( ) [− . , . ] ± : . d∗ + dijet kππs [ ] zeus - < [ . , . ] d∗ jet ( ) > > ( ) [− . , . ] [− . , . ] ± : . d∗ + jet kππs [ ] zeus - < [ . , . ] d ∗ > [− . , . ] ± : . + dijet jet ( ) > ( ) [− . , . ] ± : . lifet.+dijet imp.par. [ ] h - < [ . , . ] track jet ( ) > . > ( ) [− . , . ] [− . , . ] ± : d∗ + µ kππs + µ [ ] h - < [ . , . ] d∗ µ > . p > [− . , . ] [− . , . ] ± : . e + dijet e + e t [ ] zeus - < [ . , . ] e jet ( ) > . > ( ) [− . , . ] [− . , . ] ∼ n.a. lifet.+dijet sec. vtx. [ ] zeus < [ . , . ] tracks jet ( ) > . > ( ) [− . , . ] [− . , . ] ∼ n.a. µ + dijet µ + imp.par. [ ] h - < . [ . , . ] µ jet ( ) > . > ( ) [− . , . ] [− . , . ] ± : . d∗ incl kππs [ ] h - – < [ . , . ] d ∗ > . [− . , . ] ± : . +dijet jet ( ) > . [− . , . ] ± : . d∗ incl kππs [ ] zeus - < [ . , . ] d ∗ [ . , ] [− . , . ] ± : . mer . ± : . ler . ± : . table : charm photoproduction cross-section measurements at hera. information is given for each analysis on the charm tagging method, the experiment, the data taking period, integrated luminosity, q and y ranges and the cuts on transverse momenta and pseudorapidities of selected final state particles. the last three columns provide information on the number of tagged charm events, the effective signal-to-background ratio and the equivalent number of background-free events. the centre-of-mass energy of all data taken up to ( th column) was gev, while it was – gev for all subsequent runs, with the exception of the analyses marked “mer” and “ler” (entry ), for which the data were taken at and gev. - wγp (gev) σ (γ p → c c− x ) ( µb ) e pec slac wa emc bfp cif h tagged data h untagged data zeus qcd (mrsg + grv) upper µ/mc = . lower µ/mc = (gev)s σ r . . . . . zeus . < y < . < gev d* t . < p | < . d*η| < gev q =〉w〈 gev gev gev d* x→zeus ep nlo qcd figure : left: total charm-photoproduction cross section as a function of centre-of-mass energy wγp [ ]. the data shown are from the first h and zeus publications on open charm production and from previous fixed-target experiments. right: inclusive charm-photoproduction cross section as a function of ep centre-of-mass energy [ ], normalised to the cross section at gev. figure (right) shows the latest hera measurement in photoproduction [ ] (entry in table ), focusing on the dependence of the inclusive visible cross section on the centre-of-mass energy. this makes use of the very last hera running period, in which the proton beam energy was lowered. this result was obtained and published based on a zeus master thesis [ ], which was made possible by the strong simplification of the data format and calibration procedure implemented as part of a long-term high energy physics data preservation project [ ]. the result is presented as a ratio to the highest centre-of-mass energy cross section, such that both experimental and theoretical correlated uncertainties cancel. while the data uncertainties remain dominated by statistical uncertainties (inner error bars), the theoretical uncertainties are dramatically reduced with respect to the absolute predictions in fig. . the massive nlo prediction [ ] agrees well with the data, indicating that the extrapolation of the energy dependence to even higher centre-of-mass energies such as those at a future lhec collider [ ] can be reliably predicted. in addition, since different centre-of-mass energies correspond to different x ranges, such a ratio potentially provides constraints on the gluon pdf in the proton. . . d∗ single-differential cross sections figure shows the results for the zeus hera i [ ] and h hera ii [ ] d∗ analyses (entries and of table ) as a function of the d∗ transverse momentum and pseudorapidity. these results have been selected since the data samples used in these analyses are among those with the highest statistical significance of all heavy flavour measurements at hera, as can be seen from the last column of table (entry ). the data span a large kinematic range from pt (d ∗) = . gev ∼ mc to pt = gev ≫ mc. over this range the cross section falls off by about four orders of magnitude. the measurements are com- pared to five nlo predictions: massive fixed-flavour scheme (nlo,fmnr) calculations from frixione et al. [ ], a variant of these calculations matched to parton showers (mc@nlo) [ ], massless scheme (nll) predictions from kniehl et al. [ ], general mass variable flavour scheme (fonll) calculations from cacciari et al. [ ], and a different gmvfns variant (gmvfns) from kniehl et al. [ ]. both calculations from kniehl et al. include a perturbative treatment of the charm fragmentation function. at first glance, all five predictions are able to describe the spectrum over the complete pt (d ∗) range within a factor of two. however, looking more in detail, one observes: [ n b /g e v ] t /d p σ d - h data fmnr gmvfns mc@nlo (d*) [gev] t p n o rm r . . [ n b ] η /d σ d h data fmnr gmvfns mc@nlo (d*)η - . - - . . . n o rm r . . figure : d∗ single differential cross sections in photoproduction as function of the d∗ transverse momentum (left) and pseudorapidity (right), from zeus [ ] (top and center) and h [ ] (bottom). the measurements are compared to five nlo predictions: the massive scheme calculations from frixione et al. [ ] without (nlo, fmnr) and with (mc@nlo) [ ] interface to ll parton showering, the massless scheme predictions from kniehl et al. [ ] (nll) and the general mass variable flavour scheme calculations from cacciari et al. [ ] (fonll) and kniehl et al. [ ] (gmvfns). the nll and gmvfns predictions include a perturbative treatment of d∗ fragmentation. . the uncertainty of the measurements is generally much smaller than those of the theory, domi- nated by qcd scale variations, the variation of the charm mass, and the variation of the charm fragmentation parameters. especially for low transverse momenta pt (d ∗) < gev the scale uncertainties reach a factor of two. this indicates that in this kinematic region the hard scales provided by the charm mass and the transverse momentum of the charm quarks are not yet large enough to ensure a fast convergence of the qcd perturbation series at next-to-leading order. . as to be expected, the fonll prediction is very close to the massive nlo/fmnr prediction at low pt , and for the η distribution, which is dominated by the low pt d ∗ contribution. the measured cross sections are higher than the central prediction, but the predictions are consistent with the data within the large uncertainties. at high transverse momenta, contrary to many people’s expectations originally based on leading-order studies [ ], the fonll prediction is actually lower than the nlo prediction. thus the final state resummation corrections originating from higher-order log terms in the massless part of the calculation reduce the prediction, rather than enhancing it. the data are closer to the pure nlo prediction. at least within the hera kinematic regime there is thus no evidence for the claim [ ] that the massive fixed-order calcu- lation should fail at large values of charm transverse momentum unless final state resummation corrections are applied. both predictions give a reasonable but not perfect description of the shape of the η distribution. . the massless nll prediction, which, in contrast to the massive predictions discussed in the previous item, incorporates a proper perturbative treatment of charm fragmentation [ ], fits the data well at low pt , while it is a bit too low for high pt , where it is expected to work best. as expected, it is similar to the fonll prediction in this region. the theoretically superior treatment of fragmentation does not lead to a smaller uncertainty, as can be seen from the η distribution. also, the shape of the η distribution is a bit less well described than with the massive prediction. in this approximation, a large fraction of the cross section arises from the (massless) charm contribution to the photon parton density function (using the afg [ ] or grv [ ] parametrisations), in contrast to the “direct” contribution, which is also shown separately. . the partially massive gmvfns prediction, which incorporates a perturbative treatment of the charm fragmentation function, has a larger uncertainty than the traditional massive predictions, similar to the nll prediction. the shape of this prediction describes the data better than the nll prediction. . the mc@nlo prediction has the same core parton-level cross section as the nlo/fmnr pre- dictions by definition. the differences seen w.r.t. the latter must thus arise from the addition of the herwig-type parton showers and the different fragmentation treatment. it exhibits slighty smaller uncertainties, but, surprisingly, fits the data less well than the original nlo/fmnr pre- dictions. this offers room for potential retuning of some of the mc parameters entering this calculation. a similar inclusive d∗ photoproduction measurement as the above is available from h [ ], per- formed in a more restricted wγp region (entry in table ) with a roughly ten times smaller data sample. the narrower kinemetic range and smaller statistics are due to explicit detection of the elec- tron scattered at very low angles in dedicated forward electron taggers (section . ), which was part of the trigger requirement. the conclusions are very similar. zeus has also recorded such tagged photoproduction samples, but they were found not to be statistically competitive with results from data sets triggered on inclusive d∗ production. . . d∗ double-differential cross sections double-differential cross-section measurements as a function of the d∗ transverse momentum and pseu- dorapidity have been performed by zeus in [ ] and also in a previous charm milestone paper [ ] (entries and in table ), and by h [ ] (entry in table ). the results of the latter are shown in fig. , together with some of the predictions already discussed for the single-differential case. in general, the conclusions are similar to those from the single-differential cross sections. at high (d*)η - ( d *) [n b /g e v ] η d t /d p σ d (d*) < . gev t p≤ . (d*)η - ( d *) [n b /g e v ] η d t /d p σ d h (d*) < . gev t p≤ . (d*)η - ( d *) [n b /g e v ] η d t /d p σ d . . . . (d*) < . gev t p≤ . data fmnr gmvfns mc@nlo figure : d∗ double differential cross sections in photoproduction as function of the d∗ transverse momentum and pseudorapidity from h [ ]. the measurements are compared to three out of the five nlo predictions also shown in fig. . pt the uncertainty of the theory predictions reduces as expected, such that the comparisons become more meaningful. reasonable agreement with the data is observed for all predictions in this high-pt region, while mc@nlo undershoots the data at low pt and η, similar to what was observed in the single-differential case (fig. ). . inclusive measurements using other tagging methods although the d∗ channel generally yields the best signal-to-background ratio and therefore the best effective overall statistics (last column of table ), the small branching ratio limits the statistics in regions in which the cross section is small. in such regions, more inclusive tagging techniques can be an advantage. furthermore, the consistency of results obtained with different tagging methods enhances confidence in the results. h has performed a measurement based on inclusive lifetime tagging [ ] (entry in table ), which extends to the highest charm transverse momenta pct = gev reached so far. here events with two jets in the central rapidity region are used (cuts are listed in table ). due to the high jet transverse momenta the events are efficiently triggered using the deposits of the jet particles in the calorimeter. an inclusive lifetime tagging is applied, based on the displaced impact parameters of jet-associated charged tracks from charm and beauty decays. details of the tagging method are discussed in section . figure (left) shows the measured charm-production cross sections as function of the transverse momentum of the leading jet. the data are compared to a massive scheme nlo / gev jet t p [ p b /g ev ] je t t /d p σ d data pythia cascade had⊗nlo qcd ejjx→x c ec→ep / gev jet t p [ p b /g ev ] je t t /d p σ d data pythia cascade had⊗nlo qcd ejjx→x c ec→ep charm / gev jet t p [ p b /g ev ] je t t /d p σ d data pythia cascade had⊗nlo qcd ejjx→x c ec→ep charm(a) / gev jet t p [ p b /g ev ] je t t /d p σ d data pythia cascade had⊗nlo qcd ejjx→x c ec→ep charm(a) h / gev jet t p [ p b /g ev ] je t t /d p σ d data pythia cascade had⊗nlo qcd ejjx→x c ec→ep charm(a) h / gev jet t p [ p b /g ev ] je t t /d p σ d ( p b /g e v ) c -j e t t /d p σ d ( p b /g e v ) c -j e t t /d p σ d e→zeus - c zeus - d* jets c jet- zeus pb nlo qcd )/ t +p c =(m µ t +p c=m µ zeus ecx)→ (ep c-jet t /dpσd | < . c-jetη, . < y < . , | < gev q (gev)c-jet t p th σ/ m e a s σ (gev)c-jet t p th σ/ m e a s σ figure : left: differential cross sections for the process ep → ecc̄x → ejjx as function of the transverse momentum p jet t of the leading jet, from the h analysis [ ]. the data are compared to an nlo calculation [ ] in the massive scheme, and to lo+ps mc predictions from pythia [ ] and cascade [ ]. right: summary of differential c-quark jet cross sections as a function of the jet transverse momentum, as measured by the zeus collaboration [ ]. the data are compared to an nlo calculation [ ] in the massive scheme, for two different qcd scale choices. prediction [ ], which describes the data reasonably and equally well up to the highest jet transverse momenta. to compare this result with the above d∗ measurement (fig. ) one has to take into account that the jet gives a direct approximation of the charm quark kinematics, while on average the d∗ takes only about % of the charm quark momentum in the fragmentation (after cuts). thus, the kinematic range tested with the leading jet pt from to gev roughly corresponds to a d ∗ transverse-momentum region from to gev. for d∗ transverse momenta from gev up to the highest covered value of gev the d∗ data are similarly well described by the nlo calculation as the dijet data at their correspondingly higher momenta. so the two independent measurements using different tagging techniques give consistent results. a similar and more direct comparison is shown in fig. (right) for several measurements from zeus (entries , , in table ). here, the measurements have already been translated to cross sections for inclusive c-jet production. the results obtained from d∗ and inclusive-vertex tagging agree well with each other and with theory. since in the core of a jet electrons are not easily separated from π/π overlaps, charm tagging using semileptonic decays into electrons is experimentally difficult and the corresponding c → e result, which was a byproduct of an analysis focusing on beauty production, might several other such charm analyses were eventually not published due to insufficient control of systematics. not include all relevant systematic uncertainties. to compare with fig. (left), the prediction with scale choice m + p t (dashed line in fig. (right)) should be considered. good agreement is observed between the results of the two experiments. . studies with a d∗ and one other hard parton to obtain more information on the charm-photoproduction process, one possibility is to require the presence of a jet in the final state in addition to the d∗, which is not associated to the d∗. this means that the jet and the d∗ are well separated in their directions and that the jet tags another hard parton in the process. this parton can be the other charm quark or a gluon or light quark. in one analysis [ ] a very soft jet momentum cut pt > gev was applied. the jets were restricted to the central pseudorapidity region |η| < . , thus covering the same kinematic range as the d∗s. in fig. the differential cross sections are shown as function of the pseudorapidities of the d∗ and the jet. for the (d *) [ n b ] η /dσ d . . . p: d* + other jetγ h data had⊗fmnr fmnr had⊗zmvfns p: d* + other jetγ h (d*)η - . - - . . . r . . data had⊗fmnr fmnr had⊗zmvfns (j e t) [ n b ] η /d σ d . . . p: d* + other jetγ h data had⊗fmnr fmnr had⊗zmvfns p: d* + other jetγ h (jet)η - . - - . . . r . . data had⊗fmnr fmnr had⊗zmvfns figure : d∗ + jet cross sections as function of the pseudorapidities of the d∗ (left) and the jet (right), from the h analysis [ ]. the measurements are compared to two nlo predictions, the massive scheme (fmnr) calculations from frixione et al. [ ] and the massless scheme (zmvfns) predictions from heinrich and kniehl [ ]. leading-order boson-gluon-fusion process it is expected that the d∗ tags one charm quark and the jet the other. since similar momentum cuts are applied for the d∗ and the jet, one would expect very similar pseudorapidity distributions for the d∗ and the jet. however, the observed pseudorapidity spectrum for the jet (fig. ) is significantly shifted towards the more forward direction compared to that of the d∗. this indicates that, as expected from higher-order contributions, the jet often tags another parton, i.e. a gluon or a light quark. this effect is predicted by the massive and massless scheme nlo calculations to which the data are compared in fig. , and these calculations describe the data reasonably well. also, the additional jet requirement significantly reduces the theoretical uncertainties w.r.t. fig. . in addition to jets not associated to the d∗, the corresponding zeus measurement [ ] also selected events in which the d∗ is associated to the jet. in the latter case, one does obtain information only about one hard parton in the event, which is a charm quark. furthermore, the jet tranverse momentum cut p jet t > gev is much harder and a much wider pseudorapidity range − . < ηjet < . is covered. good agreement with nlo predictions is observed for all single-jet distributions (not shown). in particular, the et spectra for d ∗ -tagged jets (from charm quarks) and untagged jets (from charm, gluons, or light quarks) are similar. the pseudorapity distributions for d∗ -tagged and untagged jets (fig. ) show differences consistent with those of the h analysis. as expected, the average jet pseudorapity increases with increasing jet et . again, the theoretical uncertainties are reduced with respect to those of fig. . at high jet et , the shape of the massive calculation describes the data somewhat better than the massless one. zeus -tagged jet*d > gevjette zeus - jet energy scale uncertainty < gev jet t gevjette untagged jets > gevjette nlo qcd (massive) had.⊗nlo qcd (massive) beauty untagged jets > gevjette nlo qcd (massless) had.⊗nlo qcd (massless) * d→nlo qcd (massless) no b < gev jet t gevjette > gev jet te e ’+ d *+ je t+ x ) (n b) → (e p je t η /d σ d . . . . . . . . . . . jetη - jetη - jetη - figure : d∗ + jet cross sections as a function of the pseudorapidities of d∗-tagged (left) and untagged (center and right) jets, from the zeus analysis [ ]. the measurements are compared to two nlo predictions, the massive scheme calculations from frixione et al. [ ] and the massless scheme predictions from heinrich and kniehl [ ]. the selection of events with a d∗ and a muon from a semileptonic charm decay, not associated with the d∗ [ ], allows explicit tagging of both charm quarks. the small statistics (entry in table , where also the visible phase space cuts are given) do not allow differential distributions, but the observed total visible cross section for d∗µ production from double-tagged cc̄ final states of ± ± pb is consistent with the prediction from the massive nlo calculation [ ] of + − pb. . parton-parton-correlation studies in charm-tagged events analyses using tagged charm events with two identified hard partons in the final state and studying the correlations of the two partons [ , , , , , , ] provide the most detailed informa- tion on the charm-production mechanism. similar to the previous subsections, there are two different experimental approaches: • the d∗ tag is used for charm tagging. for the two hard partons either the reconstructed d∗ plus an additional non-associated jet are used [ , ], or alternatively two jets are identified, one of which is tagged by the d∗ [ , , , ]. • alternatively, dijet events are selected and one jet is tagged as a charm jet using the displaced impact parameters of jet-associated charged tracks [ ] or by a muon from a charm semileptonic decay [ ]. with the two identified partons three correlation observables are constructed, which will be discussed in the following: . the observable xobsγ , which allows the separation, in the leading order picture, of direct- and resolved-photon interactions. in the nlo picture, it separates -parton from -parton final states. . the azimuthal correlation ∆φ of the two partons, which is sensitive to higher-order effects. com- bined with xobsγ , it can distinguish between -parton, -parton and -parton final states. . the hard-scattering angle cosθ∗ of the two partons, which allows the distinction of contributions with quark or gluon propagators in the hard scattering. . . xobsγ studies the case of two jets is assumed in the following for the two hardest partons. the observable xobsγ is defined as xobsγ = ∑ jet (e − pz) + ∑ jet (e − pz) ∑ h(e − pz) . ( ) the sums in the numerator run over the particles associated with the two jets and those in the denom- inator over all detected hadronic final state particles. e and pz denote the particle energy, and the momentum parallel to the proton beam, respectively. in the leading-order pqcd picture (section . , partons + potential photon remnant + proton remnant) this variable is an estimator of the fraction of the photon energy entering the hard interaction. for the direct boson-gluon-fusion process (fig. (a)) xobsγ approaches unity, as the hadronic final state consists of only the two hard jets and the proton remnant in the forward region, which contributes little to ∑ h(e − pz). in resolved processes (figs. (b-d)) the photon remnant significantly contributes to the denominator but not to the numerator, so xobsγ can be small. the addition of parton showering can somewhat dilute this simple picture. xobsγ is also smaller than unity for next-to-leading-order processes with a third hard outgoing parton (fig. ). in the massive nlo case for charm production this often coincides with the other quark originating from initial-state photon splitting into a cc̄ pair, which would be classified as a photon remnant in the leading-order picture. since in the fixed-flavour nlo case there are at most three partons, xobsγ separates -parton from -parton final states. in the variable-flavour nlo case the two pictures described above get mixed, since in the case of an initial-state c quark from the photon the other c quark can be a fourth hard parton. thus, in general, the observable xobsγ is sensitive to the resolved-photon structure (if any) and to tree-level higher-order processes (if any). one of the milestone papers on charm photoproduction at hera was the zeus analysis [ ], where xobsγ studies are performed using events with a d ∗ and two jets. the jets are required to have transverse momenta p jet ( ) t > ( ) gev and are selected in a wide rapidity range |ηjet| < . . in most events the d∗ is associated to one of the two jets. figure shows the measured single-differential cross section as a function of xobsγ . a peak at large x obs γ > . is observed, which reflects the direct- photon/ -hard-parton component. roughly % of the data are observed at xobsγ < . , indicating large contributions from resolved-photon/ -hard-parton or other higher-order contributions. in the lower plot in fig. the data are compared to predictions from a massive scheme nlo calculation [ ]. not all theoretical uncertainties are shown here. the calculation has a tendency to underestimate the data cross sections at xobsγ < . , where it is effectively a leading order calculation. this might indicate the need for even higher-order corrections. . . . . . . . . zeus + xγobs d σ /d x γ o b s (n b ) (a) data herwig: direct + resolved herwig: direct herwig: resolved herwig: resolved without charm excitation xγobs d σ /d x γ o b s (n b ) (b)(b) data massive nlo, parton level, ε= . µr = . m⊥ , mc = . gev µr = . m⊥ , mc = . gev figure : differential cross section as a function of xobsγ for dijet events with an associated d ∗ meson, from a zeus analysis [ ]. the shaded band indicates the energy scale uncertainty. the same data are compared in the lower plot to an nlo calculation [ ], and in the upper plot to monte carlo predictions from herwig [ ] with direct and resolved photon contributions shown separately. the latter is dominated by the charm excitation component. a much better shape description is obtained with the lo+ps herwig [ ] monte carlo program as shown in the upper plot of fig. . in this calculation a large part of the nlo photon splitting diagram in fig. (c) is included in the form of a charm excitation component, where the charm quark is treated as a massless constituent of the resolved photon, as shown in figs. (c) and (d). this gives the dominant contributions for xobsγ < . . combined with parton showering, which also pulls the “direct” contribution towards lower xobsγ values, this provides a reasonable data description. this lo+ps mc approach thus provides an effective way to describe the small xobsγ region, although the charm quark is treated as massless in a kinematic region where this is probably not a good approximation. note that the total cross section with d∗ + dijets is only about % of the d∗ cross section without the dijets, also measured in [ ], for the same d∗ cuts applied (pt (d ∗) > gev and |η(d∗)| < . ). thus the problematic (for nlo) xobsγ < . region in the d ∗ + dijet sample contributes only a relatively small part to the inclusive-d∗ cross section. another zeus analysis [ ] using events with a d∗ and at least one jet compares the measured xobsγ cross sections to both massive and massless scheme nlo calculations. here the d ∗ and a jet, to which the d∗ is not associated, are taken as estimators for the two leading partons and used for the xobsγ reconstruction in eq. ( ). the jet is required to have transverse momentum pt > gev in a pseudorapidity range − . < η < . . figure shows the differential cross sections as a function of note that the available massless scheme calculations [ ] provide only cross sections for a d∗ + jet final state but not for two jets. xobsγ . in the left (right) plot the data are compared to the massive (massless) scheme nlo predictions. both predictions are a bit too low for the -or-more-parton final state region xobsγ < . , but are still compatible with the data within their uncertainties. note that in the massless calculation, which absorbs the initial state photon splitting to cc̄ into the photon pdf, this contribution is effectively calculated to nlo (one-loop virtual corrections), while it is only calculated to lo ( loop) in the massive case. this partially explains why the uncertainty of the massless calculation is much smaller in this region. at high xobsγ both calculations are effectively nlo ( -loop) calculations, and the uncertainties are similar. figure : differential cross sections as a function of xobsγ for events with a jet and a d ∗ meson, which is not associated to the jet, from the zeus analysis [ ]. in the left (right) upper plots the data are compared to a nlo calculation in the massive [ ] (massless [ ]) scheme. the bottom plot shows a comparison to the pythia and herwig mc, which were used to calculate the hadronisation corrections in the upper left plot. . . azimuthal correlations ∆φ in a zeus analysis [ ] using events with a d∗ and two jets (entry in table ), and in the h measurement [ ] with a d∗ and a non-associated jet (entry ), the azimuthal correlation of the two hard partons is investigated. in the leading-order picture of direct-photon interactions (fig. a), the two charm quarks are produced back-to-back in the azimuthal plane of the lab frame, i.e. with ∆φ = ◦. smaller ∆φ can be due to higher-order processes, such as gluon radiation, or due to a non- zero transverse momentum of the partons that enter the hard interaction, e.g. from a flavour-excitation process in which the c quark gets a finite transverse momentum in the backwards parton showering step. in the zeus analysis jets were selected with harder transverse-momentum requirements but in a wider η range than in the h analysis (cf. entries and in table ). figure shows the differential cross sections as a function of the azimuthal difference ∆φ between the d∗ and the jet for the h analysis and between the two jets for the zeus measurement. the h result is shown in the two rightmost plots. the cross sections are highest for ∆φ = ◦, i.e. for the back-to-back configuration, and drop off towards smaller angles. nlo calculations in the massive scheme [ ] and in the massless scheme [ ] are compared to the data. both calculations drop off more steeply than the data towards smaller opening angles. below ∆φ ≈ ◦ the two calculations predict very small contributions, while there are still sizeable ones in the data. a better description is obtained with the lo+ps programs pythia [ ] and cascade [ ]. pythia includes charm excitation processes in resolved-photon events, which give the dominant contribution for ∆φ < ◦ and provide a reasonable data description in this region. the results of the zeus analysis [ ] are shown in the left and central plots of fig. . here the azimuthal correlation is measured separately in the -parton region xobsγ > . and in the -or- more-parton region xobsγ < . . the data are compared to an nlo calculation [ ] in the massive scheme. for the high-xobsγ region the description is satisfactory. however, in the low-x obs γ region the nlo calculation is clearly falling below the data for ∆φ < ◦. this is straightforward to understand since a -parton final state can not produce an angle between the two leading pt partons of less than ◦ . correspondingly, at least four partons are needed to populate this region. a massive nlo calculation produces at most three, so an nnlo calculation is needed to fill the gap. again, a better shape description is obtained by pythia and herwig, which can provide several extra partons through parton showering (of which flavour excitation is a part). thus, the conclusion is again very similar to the above studies with the xobsγ observable: the nlo calculation is missing a component in the data, which can be effectively described by a lo+ps calculation. as to be expected from this explanation, in the two lower plots the mc@nlo calculation, which complements the - and -parton nlo matrix elements by parton showering, is able to describe these data well. an h analysis using µ+dijet final states [ ] (entry in table ) further supports these conclu- sions. . . study of hard-scattering angle cos θ∗ in a dedicated analysis [ ], using events with a d∗ and two jets (entry in table ), zeus has investigated the scattering angle θ∗ of the charm quark with respect to the proton direction in the dijet rest frame. the charm quark is identified by the jet to which the reconstructed d∗ is associated. the cos θ∗ distribution strongly reflects the type of the propagator particle exchanged in the → hard interaction: • for a charm quark propagator cos θ∗ should follow a ( − |cos(θ∗)|)− distribution. the direct photon (fig. (a)) and the resolved process with a gluon from the photon structure (fig. (b)) belong to this class of processes and also one of the charm excitation diagrams (fig. (c)). • for a gluon propagator cos θ∗ should follow a ( − |cos(θ∗)|)− distribution, i.e. a much steeper rise for |cos θ∗| → . for leading-order processes only the charm-excitation mechanism provides such a contribution (fig. (d)). the main idea of the analysis is to look for such effects directly in the data. special cuts are applied in order to ensure a flat acceptance for the cos θ∗ distribution over a wide range, extending to as large values of |cos θ∗| as possible. the invariant mass of the two jets is required to be above gev. the however, in the -parton topology one of the leading jets can escape outside of the kinematic region of the mea- surement. thus, the softest jet is used instead, which leads to strongly suppressed but non-zero charm contribution for ∆φ < ◦ zeus - - - - > . obsγx zeus - jet energy scale uncertainty - - - - < . obsγx nlo qcd (massive) had.⊗nlo qcd (massive) beauty - - - - > . obsγx . ×herwig . ×pythia - - - - < . obsγx e ’+ d *+ jj + x ) (n b/ ra d. ) → (e p jj φ∆ /d σ d (rad.) jj φ∆ (rad.) jj φ∆ ]° (d *, j e t) [n b / φ ∆ /d σ d - - - p: d* + other jetγ h data cascade . pythia . pythia . (dir.) p: d* + other jetγ h ]°(d*, jet) [φ ∆ r . . data cascade . pythia . pythia . (dir.) [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - xµ ejj→xc ec→h cross section: ep > . obsγx [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - h data / pythia cascade herwig mc@nlo [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - xµ ejj→xc ec→h cross section: ep . ≤obsγx [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - h data / pythia cascade herwig mc@nlo ]° (d *, je t) [ n b / φ ∆ /d σ d - - - p: d* + other jetγ h data had⊗fmnr fmnr had⊗zmvfns p: d* + other jetγ h data had⊗fmnr fmnr had⊗zmvfns p: d* + other jetγ h ]°(d*, jet) [φ ∆ r . . data had⊗fmnr fmnr had⊗zmvfns figure : azimuthal differences of two outgoing hard partons in charm events. the upper row shows the d∗-tagged jet-jet azimuthal difference from zeus [ ] separately for the high (left) and low (middle) xobsγ region and the d ∗-other jet azimuthal difference from h [ ] without cut on xobsγ (right). also shown are massive (nlo/fmnr)[ ] and massless (zmvfns)[ ] nlo predictions. the middle row shows the same data compared to herwig[ ], pythia[ ] and cascade[ ] lo+ps mc predictions. the bottom row shows the muon-tagged jet-jet azimuthal difference from h [ ] compared to these same mcs and to the nlo+ps mc@nlo [ ] prediction. average pseudorapidity of the two jets, defined as η jet +ηjet is required to be smaller than . . note that these cuts yield a much smaller (but still sizeable) contribution at xobsγ < . than the one shown in fig. , mainly because they implicitly restrict the two jets to the pseudorapidity region ηjet < . . as intended, this analysis mainly probes -parton final states, plus a potential rd parton from the photon remnant. in fig. the differential cross sections are shown as a function of cosθ∗, separately for xobsγ < . and x obs γ > . . in the lower half of fig. the data are compared to massive scheme figure : differential cross sections as function of cos θ∗ for dijet events with an associated d∗ meson [ ]. results are given separately for samples enriched in direct (xobsγ > . ) and resolved photon events (xobsγ < . ). the data are compared in the lower two plots to nlo predictions [ ] in the massive scheme using the parameter settings and variations listed in table . the predictions of the cascade [ ] mc are also shown. in the upper two plots the data are compared to predictions using the herwig [ ] and pythia [ ] mcs. nlo predictions [ ]. for the xobsγ > . region the nlo calculation provides a good description of the data over the whole range of cos θ∗, with reasonably small uncertainty. the relatively shallow cos θ∗ dependence is consistent with the expectation that this region is dominated by the boson-gluon-fusion graph, where the propagator particle is a charm quark, and for which the prediction is stabilised at nlo by -loop virtual corrections. in the xobsγ < . region a much stronger rise is visible towards more negative cos θ∗ values, and the central region is more strongly depleted. this can be interpreted as a direct proof for sizeable contributions from gluon propagator exchanges such as the charm excitation process (fig. (d)), which at nlo is a tree-level process (fig. (d,e) ). correspondingly, the nlo uncertainty is much larger. the upper edge of the uncertainty band describes the data reasonably. the strong asymmetry can be attributed to the fact that the charm jet will preferentially be correlated with the incoming photon direction. the plots in the upper half of fig. show that the pythia and herwig lo+ps mcs with their large excitation contributions are able to describe the data well everywhere. this is particularly true for pythia. for the nlo calculation this means that contributions beyond nlo would probably further improve the description. on the other hand, the cascade mc, which attempts to describe hard higher-order topologies by allowing initial state partons to have sizeable transverse momentum, reasonably describes the shapes, but fails to describe the relative normalisation of the low- and high-xobsγ regions. . summary the charm mass provides a semi-hard qcd scale which already allows the application of perturbative calculations to all of phase space, but which also competes with other, often even harder perturbative scales. total cross sections for charm photoproduction are reasonably described by such calculations. single-differential cross sections already provide a good handle to test the applicability of different qcd approximations, although the theoretical uncertainties are mostly much larger than the experimental ones. the theory predictions agree with the data up to the highest accessible transverse momenta, showing no indications that final state resummation corrections are needed for massive calculations. double-differential cross sections, in particular those including jets, reveal a partial failure of the massive scheme nlo predictions for the three independent parton-parton kinematic observables xobsγ , cos θ∗ and ∆φ, which were studied in charm events with a d∗ and one or two jets. for certain kinematic regions this can be traced back to the absence of -or-more-parton final states in the calculation. the partially large theoretical uncertainties can be explained by the absence of stabilizing virtual corrections for -parton final states at this order. the nlo calculations in the massless scheme, where available, do mostly not provide a better description for the observables. the lo+ps mcs pythia and herwig, which are often used for acceptance corrections, are able to describe all topologies reasonably, often even very well. the cascade mc performs somewhat less well on average. beauty photoproduction from the theoretical point of view, the only differences between charm photoproduction as discussed in the previous section and beauty photoproduction are the beauty-quark mass and electric charge. the first suppresses the cross section w.r.t. charm at low values of transverse momentum, while the second suppresses it by about a factor everywhere (eq. ). experimentally, the signal-to-background ratio is thus more challenging, and the available statistics is smaller. together with the small branching ratio to specific final states, this precludes any attempt to use fully-reconstructed beauty-hadron final states at hera. on the other hand, the higher mass and longer lifetime compared to charm hadrons increases the tagging efficiency for inclusive tagging methods. table summarises all h and zeus beauty photoproduction measurements. for the reasons explained above, the first such measurements (entries and ) came several years after the first mea- surements of charm, focused on beauty jet production, and were severely limited by statistics. . total cross section for beauty production due to their high mass, even beauty quarks at rest in the centre-of-mass system of the partonic in- teraction still produce reasonably high-momentum muons or electrons, which can be detected, when decaying semileptonically. the forward and backward muon systems allow the detection of such beauty quarks even when they are strongly boosted along the beam direction. furthermore, the requirement of two such muons, i.e. a double tag, strongly reduces both the light flavour and charm backgrounds. in a zeus analysis [ ] these properties were used to measure the total cross section for beauty production in ep collisions without any cuts, i.e. including both photoproduction and dis, by pushing the measureable muon phase space to the limit (entry of table ). after correcting for muon acceptance and semileptonic branching ratios the resulting total cross section for bb̄ pair production in ep collisions at hera for √ s = gev was determined to be σtot(ep → bb̄x) = . ± . (stat.)+ . − . (syst.) nb, ( ) where the first uncertainty is statistical and the second systematic. the total cross section predicted by next-to-leading-order qcd calculations was obtained in the massive approach by adding the predictions from fmnr [ ] and hvqdis [ ] for q less than or larger than gev , respectively. the resulting cross section for √ s = gev, using the scale choice µ = √ m b + p tb σnlotot (ep → bb̄x) = . + . − . nb ( ) is a factor . lower than the measured value, although compatible within the large uncertainties. compareable measurements were obtained in reduced regions of phase space from d∗ + muon and dielectron final states (entries , and in table ), and similar results were obtained for the ratio of measured to predicted cross sections (see also corresponding entries in fig. ). since d∗ mesons and semi-isolated electrons could only be measured in the more central rapidity range, total bb̄ cross sections were not extracted. . single-differential cross sections in order to make them compareable with each other, in fig. almost all available beauty-photopro- duction cross sections have been translated, using nlo massive qcd calculations, into cross sections for inclusive b-quark production as a function of ptb in the kinematic range q < gev , . < y < . entries , , , , , , , , , , in table , following the order in the figure legend no. analysis b tag ref. exp. data l [pb− ] q [gev ] y particle pt [gev] η events bgfree events µ + dijets µ + prel t [ ] h . < [ . , . ] µ jet ( ) > > ( ) [− . , . ] ± e + dijets e + prel t [ ] zeus - . < [ . , . ] e jet ( ) > . > ( ) [− . , . ] [− . , . ] ± µ + dijets µ + prel t [ ] zeus - < [ . , . ] µ jet ( ) > . > ( ) [− . , . ] [− . , . ] ± µ + dijets µ + prel t + δ [ ] h - < [ . , . ] µ jet ( ) > . > ( ) [− . , . ] [− . , . ] lifet.+dijets imp. par. [ ] h - < [ . , . ] track jet ( ) > . > ( ) [− . , . ] [− . , . ] ∼ e + dijets e + prel t + e t [ ] zeus - < [ . , . ] e jet ( ) > . > ( ) [− . , . ] [− . , . ] ∼ µ+dijets µ + prel t + δ [ ] zeus < [ . , . ] µ jet ( ) > . > ( ) [− . , . ] [− . , . ] lifet.+dijets sec. vtx. [ ] zeus < [ . , . ] tracks jet ( ) > . > ( ) [− . , . ] [− . , . ] ∼ µ + dijets µ+imp.par. [ ] h - < . [ . , . ] µ jet ( ) > . > ( ) [− . , . ] [− . , . ] d∗ + µ kππs + µ [ ] h - < [ . , . ] d∗ µ > . p > [− . , . ] [− . , . ] ± d∗ + µ kππs + µ [ ] zeus - < [ . , . ] d∗ µ > . > . [− . , . ] [− . , . ] dimuon µ + µ [ ] zeus - all all µ ( ) > . ( . ) [− . , . ] dielectron e + e [ ] h < [ . , . ] e > [− . , . ] ∼ table : beauty photoproduction cross-section measurements at hera. information is given for each analysis on the beauty tagging method, the experiment, the data taking period, integrated luminosity, q and y ranges and the cuts on transverse momenta and pseudorapidities of selected final state particles. the last two columns provide information on the number of events in the analysis (number of signal events if an uncertainty is given) and the equivalent number of background-free events. the centre-of-mass energy of all data taken up to ( th column) was gev, while it was – gev for all subsequent runs. ( p b /g e v ) b t /d p σ d - ( p b /g e v ) b t /d p σ d - µh - d* h - b jet jetµ →h - b ee→h b e→zeus - b µ d* →zeus - b µ →zeus - b e→zeus - b jetµ →zeus b µµ → bb - zeus pb b jet- zeus pb nlo qcd )/ t +p b =(m µ t +p b=m µ hera ebx)→ (ep b t /dpσd | < b η, . < y < . , | < gev q (gev)b t p th σ/ m e a s σ (gev)b t p th σ/ m e a s σ figure : differential cross section as a function of the transverse momentum of b quarks for the kinematic range indicated in the figure. the bottom inset shows the ratio of the measured cross sections to the central nlo qcd prediction. for more details see the text. and beauty pseudorapidity |ηb| < . each data point is displayed at the centroid of the pt distribution of the b quarks entering the measurement bin of the respective analysis, which is mostly a bin in b-jet et , or, where not available, a bin in muon or electron pt . the b-quark pt rather than the b-jet pt has been chosen here because the measurements extend down to very low pt at which jets can not be usefully defined any more. two massive nlo [ ] theory predictions are given: one with scale choice µ = √ m b + p tb (dashed), and one with scale choice µ = √ m b + p tb/ . the full theory uncertainty band is shown for the latter (for the scale choice see also section . ). it is dominated by the scale variations (independent variation of renormalisation and factorisation scales by factor ) and by the variation of the pole mass (mb = . ± . gev). where not provided directly in the original publications, the data points were obtained using the data/theory ratio of the respective original measurements and rescaling them to the theory prediction in fig. , properly accounting for differences in the respective theory calculation settings. within the large uncertainties, reasonable agreement between theory and data is observed over the complete pt range covering orders of magnitude in the cross section. in particular, as in the charm case, there is no indication for a failure of the predictions at large pt . there might be a trend that on average, the measurements of the double tagging analyses (d∗µ, ee and µµ), which were already briefly discussed in the total cross-section subscetion, tend to lie a bit above the other measurements which typically require dijet final states. the effect is not very significant, but if taken serious, might indicate that the contribution of b quarks not associated to jets might be underestimated by the theory. unfortunately, currently no measurement is available which directly tests this hypothesis by considering both topologies in a single analysis framework. all available beauty photoproduction results are represented in this plot, except the results of the very first h analysis [ ] (entry in table ), which has been declared superseded by a more recent analysis [ ], and the results of one of the latest h analyses [ ] (entry ), for which no comparison to pure nlo predictions was provided. double-differential cross sections have not been measured so far. in the future they could best be extracted using the inclusive vertexing approach [ ], which offers the best effective statistics (entry in table ). figure : single-differential cross sections for muons from bb̄ decays to dimuons, as a function of the muon transverse momentum (left), pseudorapidity (center), and dimuon azimuthal angle difference (right), from zeus [ ]. the measurements are compared to massive nlo predictions with the same settings as the band in fig. , and to the pythia [ ] prediction scaled to the data. . measurements of bb̄ and jet-jet correlations several results give insight into correlations between two final state partons in bb̄ events. the zeus analysis of dimuon final states (fig. , entry in table ) studies the azimuthal angle difference between muons originating from different b quarks, in addition to single-differential distributions. both the massive nlo predictions and the pythia mc predictions used for acceptance correction show reasonable agreement with the data, in particular in shape. an h analysis of dijet final states in which one of the jets is tagged by a muon from a semilep- tonic b decay (fig. , entry in table ) studies the xobsγ and ∆φ variables described earlier in the charm section. the mc@nlo prediction describes the data, except in the high xobsγ , high ∆φ bin. obs γx . . . . [ p b ] γ /d x σ d obs γx . . . . [ p b ] γ /d x σ d xµ ejj→xb eb→h cross section: ep h data / pythia cascade herwig mc@nlo obs γx . . . . [ p b ] γ /d x σ d [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - xµ ejj→xb eb→h cross section: ep > . obsγx h data / pythia cascade herwig mc@nlo [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - xµ ejj→xb eb→h cross section: ep . ≤obsγx h data / pythia cascade herwig mc@nlo [deg] jj φ∆ [ p b /d e g ] jj φ∆ /d σ d - - figure : beauty cross sections as a function of xobsγ (left) and as a function of the jet-jet azimuthal angle difference ∆φ for high (center) and low (right) values of xobsγ , from a recent h analysis [ ]. the measurements are compared to mc@nlo [ ] predictions, as well as to predictions from the pythia [ ], herwig [ ] and cascade [ ] lo+ps monte carlos. the agreement is thus slightly worse than in the charm case (fig. ). pythia agrees everywhere, herwig describes the shape but not the normalisation, and cascade fails for both. the latter finding is again in qualitative agreement with the charm result. thus the pythia or herwig mcs should preferentially be used for acceptance corrections. a similar analysis by zeus [ ] (not shown) compares the data directly to the massive nlo predictions. not surprisingly, these predictions fail in the same kinematic regions as for charm (fig. ), for the same reasons as discussed there. several other analyses [ , , ] also studied xobsγ , with less statistics than but similar conclu- sions as for charm. . summary due do the suppression of the cross section by mass and charge, and small branching ratios to exclusive final states, only inclusive or semi-inclusive tagging methods can be used at hera to measure beauty production. the reasonable acceptance for the detection of b hadron decays down to transverse mo- mentum and the coverage of almost the full physically relevant rapidity range allowed the measurement of the total beauty production cross section at hera. this cross section is higher than, but still com- patible with, nlo qcd predictions. several single differential beauty photoproduction cross sections have also been measured. the measurements from h and zeus and from different final states agree reasonably well with each other and with qcd predictions from threshold up to the highest accessible transverse momenta. double differential cross sections have not yet been measured. charm and beauty production in dis in the previous sections and heavy-flavour production in ep collisions with the exchange of quasi- real photons was discussed. the production of charm and beauty quarks was also studied in the deeply inelastic scattering regime, which corresponds to photon virtualities q ∼> gev . large photon virtuality provides an additional hard scale in the calculations and allows probing the parton dynamics inside the proton with high resolution. an overview of all measurements is given in table and table for charm and beauty production, respectively. . production mechanism already in the first h [ ] and zeus [ ] measurements in dis (entries and in table ) boson- gluon fusion was clearly identified to be the dominant production mechanism for charm quarks. this was investigated using the distribution of the fractional momentum of d∗ mesons in the γp system, xd = p∗ d wγp , where p∗d denotes the d ∗ momentum measured in the γ∗p frame. the data were used to disentangle between bgf and qpm-like models (cf. fig. (a) and fig. ). the bgf process produces a cc̄ pair that recoils against the proton remnant in the γ∗p frame, while the (massless) qpm produces a single charm quark recoiling against the proton remnant (which contains the other charm quark). since the d meson carries a large fraction xd of the charm quark momentum, the former model should lead to significantly softer distribution in xd. figure shows a comparison of the two models against the zeus data. the observed shape of the cross section in the data proves that bgf is the dominant figure : normalised differential d∗ -production cross section as a function of x∗d [ ]. the mea- surement was performed for < q < gev . the points show the data, while solid and dashed lines show the bgf (pgf) and qpm predictions. charm-production process in dis at hera. this was quantified in [ ] in the leading order qcd picture by setting an upper limit for the fraction of the qpm-like contribution f(qpm) to charm dis production to be below . at % c.l. . single-differential cross sections transition from photoproduction to dis: the zeus collaboration has studied [ ] (entry in table ) charm production in the intermediate q region between photoproduction and dis: . < q < . gev . the scattered electron was detected with the beampipe calorimeter (bpc) at very small scattering angles. figure (a) shows a comparison of the massive-scheme nlo qcd predictions [ ] no. analysis c-tag ref. exp. data l [ pb− ] q [gev ] y particle pt [gev] η events effect. s:b bgfree events d∗ incl. kππs [ ] h [ , ] < . d ∗ > . [− . , . ] ± : . d incl. kπ d > . ± : . d∗ incl. kππs [ ] zeus [ , ] < . d ∗ [ . , . ] [− . , . ] ± : . d∗ incl. kππs [ ] h - [ , ] [ . , . ] d ∗ [ . , ] [− . , . ] ± : . d∗ incl. kππs [ ] zeus - [ , ] [ . , . ] d ∗ [ . , ] [− . , . ] ± : . kππππs [ . , ] ± : d∗ incl. kππs [ ] h [ , ] [ . , . ] d ∗ > . [− . , . ] ± : . d∗ incl. kππs [ ] zeus - [ . , ] [ . , . ] d ∗ [ . , ] [− . , . ] ± : d incl. d mes. + s [ ] h - [ , ] [ . , . ] d mesons > . [− . , . ] n.a. n.a. d∗ incl. kππs [ ] h - [ , ] [ . , . ] d ∗ [ . , ] [− . , . ] ± : . + dijet jet ( ) > ( ) [− , . ] ± : . d∗ incl. kππs [ ] zeus - [ . , . ] [ . , . ] d ∗ [ . , ] [− . , . ] ± : . d incl. d mes. [ ] zeus - [ . , ] [ . , . ] d mesons > [− . , . ] n.a. n.a. d+ incl. kππ [ ] zeus - [ . , ] [ . , . ] d+ [ , ] [− . , . ] ± : Λc incl. pk s Λc ± : Λπ+ ± : incl. lifet. imp. par. [ ] h - > [ . , . ] track > . [− . , . ] ∼ : incl. lifet. imp. par. [ ] h - [ , ] [ . , . ] track > . [− . , . ] ∼ : d incl. kπ + s [ ] zeus [ , ] [ . , . ] d [ . , ] [− . , . ] ± : µ + jet µ + prel t + δ + e t [ ] zeus > [ . , . ] µ > . [− . , . ] ∼ : d∗ incl. kππs [ ] h - [ , ] [ . , . ] d ∗ [ . , ] [− . , . ] ∼ : d∗ incl. kππs [ ] h - [ , ] [ . , . ] d ∗ > . [− . , . ] ± : . d∗ incl. kππs [ ] zeus - [ , ] [ . , . ] d ∗ [ . , ] [− . , . ] ± : . d+ incl. kππ + s [ ] zeus - [ , ] [ . , . ] d+ [ . , ] [− . , . ] ± : . incl. lifet. δ + s [ ] h - [ , ] n.a. track > . [− . , . ] ∼ n.a. n.a. incl. lifet. jet + δ + s [ ] h - > [ . , . ] jet > [− . , . ] ∼ : incl. lifet. jet + s [ ] zeus - [ , ] [ . , . ] jet > . [− . , . ] ∼ : table : charm dis measurements at hera. information is given for each analysis on the charm tagging method, the experiment, the data taking period, integrated luminosity, q and y ranges and the cuts on transverse momenta and pseudorapidities of selected final state particles. the last three columns provide information on the number of tagged charm events, the effective signal-to-background ratio and the equivalent number of background-free events. the centre-of-mass energy of all data taken up to ( th column) was gev, while it was – gev for all subsequent runs. no. analysis c-tag ref. exp. data l [ pb− ] q [gev ] y particle pt [gev] η events effect. s:b bgfree events µ + jet µ + prel t [ ] zeus - > [ . , . ] µ jet > ebr t > [− . , . ] [− , . ] ∼ : . µ + jet µ + prel t [ ] h - [ , ] [ . , . ] µ jet > . pbr t > [− . , . ] [− . , . ] ∼ : . µ + jet µ + prel t [ ] zeus - > [ . , . ] µ jet > . > > − . [− , . ] ∼ : µ + jet µ + prel t + δ + e t [ ] zeus > [ . , . ] µ > . [− . , . ] ∼ : e + jet e + prel t + δ + e t [ ] zeus - > [ . , . ] e [ . , ] [− . , . ] ∼ : d∗ + µ kππs + µ [ ] zeus - > [ . , . ] d∗ µ > . > . [− . , . ] [− . , . ] ∼ : incl. lifet. imp. par. [ ] h - > [ . , . ] track > . [− . , . ] ∼ : incl. lifet. imp. par. [ ] h - [ , ] [ . , . ] track > . [− . , . ] ∼ : incl. lifet. δ + s [ ] h - [ , ] n.a. track > . [− . , . ] ∼ n.a. n.a. incl. lifet. jet + δ + s [ ] h - > [ . , . ] jet > [− . , . ] ∼ : incl. lifet. jet + s [ ] zeus - [ , ] [ . , . ] jet > [− . , . ] ∼ : table : beauty dis measurements at hera. information is given for each analysis on the beauty tagging method, the experiment, the data taking period, integrated luminosity, q and y ranges and the cuts on transverse momenta and pseudorapidities of selected final state particles. the last three columns provide information on the estimated number of tagged beauty events, the effective signal-to-background ratio and the equivalent number of background-free events. the centre-of-mass energy of all data taken up to ( th column) was gev, while it was – gev for all subsequent runs. the ”br” label in the superscript refers to measurements in the breit frame (see text). zeus - - - - - q (gev ) d σ /d q ( n b /g e v ) zeus bpc zeus dis - hvqdis e p → d* x (a) zeus - - - q (gev ) σ γp (w = g e v ) ( n b ) zeus bpc zeus dis - zeus photoproduction - γ p → d* x (b) figure : (a) differential ep cross section for d∗ production as a function of q [ ] in the kinematic region indicated in table . the measurements [ , ] are compared to massive-scheme nlo qcd predictions (hvqdis) [ ]. (b) differential γp cross section for d∗ production as a function of q [ ]. the d∗ data are shown in the photoproduction [ ], transition [ ] and dis [ ] regions. the curve shows a fit to the data (see text). to these very-low-q as well as q > . gev data [ ] (entry in table ). the calculations provide a remarkable description of the drop of the measured cross sections over orders of magnitude from q = . gev ≪ m c to q = gev ≫ m c. the slope of dσ/dq changes with q : it is steeper at high q > m c, where it is mainly dictated by the photon-propagator dependence /q , than at low q < m c, where an asymptotic /q dependence is expected. to study this further, the measured d∗ electroproduction cross sections were converted into γ∗p cross sections using the photon flux in the improved weizsäcker-williams approximation (see section . ). figure (b) shows the converted dis as well as the photoproduction cross sections [ ] (entry in table ). the very-low- q measurements are consistent with the photoproduction cross section. the data were fitted with a function σγp(q ) ∝ m /(q +m ). the extracted value was m = ± gev , which is close to m c and is significantly larger than the value obtained from inclusive data, m = . ± . gev ≃ m ρ [ ]. performance of the zmvfns: d∗ -production single-differential cross sections in dis have also been used to test available calculations in the massive and massless schemes. figure shows a com- parison of the most precise measurements from h [ , ] (entries and in table ) to nlo qcd calculations. since the zmvfns calculation is only valid in the regime where the charm-quark mass can be neglected, an additional restriction is needed on the d∗ transverse momentum in the γ∗p frame, p∗t (d ∗) > gev, on top of the selection outlined in table . this is compareable to the cuts used in the photoproduction analysis, for which the laboratory frame approximately coincides with the γp system (see fig. ). the inelasticity is correlated with the centre-of-mass energy in the γ∗p frame, wγp (see eq. ( )), thus the low-y region corresponds to the low-wγp region. therefore, as expected, the zmvfns predictions deviate significantly from the massive-scheme calculations at low y, where wγp is not ≫ m c, and come close to the ffns calculations at high y. at low y the massless-scheme calculations clearly fail to describe the data, while massive predictions are in agreement with the mea- surement in the whole y range. also for q > gev the massive predictions describe the data well within uncertainties, whereas the massless approach significantly overestimates the charm cross section. the actual kinematic threshold for a d∗ −d meson pair with only the d∗ detected is ( √ m(d∗) + pt (d∗) +md) − pt (d ∗) = gev . . . . . . . . / d y [ n b ] σ d . . . . . . . / d y [ n b ] σ d h data zm-vfns (cteq . m) hvqdis (ct f ) . . . . . . . / d y [ n b ] σ d d* in dis h y . . . . . . . n o rm r y . . . . . . . n o rm r (a) q [gev ] d σ v is /d q [ n b g e v - ] h - - - h data hvqdis zmvfns p*t(d*) > gev (b) figure : differential d∗-production cross section as a function of y for q < gev [ ] (a) and as a function of q for q > gev [ ] (b). also shown are the massive nlo prediction (hvqdis) [ ] and the massless nlo prediction (zmvfns) [ , ]. the ratio shown on the left, rnorm, represents the ratio of individually-normalised distributions to the data, thus allowing a comparison of shapes only. the data also clearly establish that the zmvfns fails to describe heavy-flavour production in dis at hera. similar conclusions were drawn in [ ] (entry in table ), but with a lower precision of the data. event and heavy-flavour kinematics: most of the analyses summarised in tables and studied event, charm and beauty kinematics differentially in the respective fiducial phase spaces. the most precise d∗ measurements [ , , ] (entries – in table ) were combined [ ] to obtain the most precise charm differential cross sections with essentially no theory uncertainty due to extrapolation to a common phase space. the combination was done with a careful treatment of correlations. as expected, the individual measurements were found to be consistent. the uncorrelated uncertainties were reduced due to effective doubling of statistics, while the correlated systematic uncertainties were reduced through cross-calibration effects between the two experiments. figure (a)–(c) shows a comparison of massive-scheme nlo qcd predictions [ ] to the d∗ combined single-differential cross sections. the predictions describe the data very well within uncertainties. however, the data reach % precision over a large fraction of the measured phase-space, whereas the typical theory uncertainty ranges from % at low q to % at high q . the theory uncertainty is dominated by the independent variation of the µr and µf scales, the uncertainty on the charm-quark pole mass and variations of the fragmentation model. therefore, higher-order massive-scheme nnlo calculations and an improved fragmentation model for these predictions are needed to fully exploit the potential of these data. in addition, theory uncertainties were studied in detail and a “customised” prediction was obtained by a variation of the theory parameters within their uncertainties, to show that the calculations can simultanously provide a good description of the shape and normalisation of all measured distributions with a single set of parameters. this led to a renormalisation scale reduced by a factor (see also section . ), the charm-quark pole mass reduced to mc = . gev and to a change of fragmentation parameters, all within the nominal uncertainties. moreover, differential cross sections of other d mesons as well as of leptons from heavy-flavour decays and of heavy flavour jets were measured. in particular, fig. (d) shows the d+ differential (d*)η - . - - . . . ( d *) ( n b ) η /d σ d hera-ii nlo qcd nlo qcd customised ± d*→nlo qcd b < gev < q . < y < . (d*) > . gev t p (d*)| < . η| x h and zeus± ed*→ ep (a) ( d *) ( n b /g e v ) t /d p σ d - - - - (d*) (gev) t p ra ti o t o h e r a . . . hera-ii nlo qcd nlo qcd customised ± d*→nlo qcd b < gev < q . < y < . (d*) > . gev t p (d*)| < . η| x h and zeus± ed*→ ep (b) ) ( n b /g e v /d q σ d - - - - - ) (gev q ra ti o t o h e r a . . . . hera-ii nlo qcd nlo qcd customised ± d*→nlo qcd b < gev < q . < y < . (d*) > . gev t p (d*)| < . η| x h and zeus± ed*→ ep (c) (d) figure : differential d∗ -production cross section [ ] as a function of (a) η(d∗), (b) pt (d ∗) and (c) q . the data points are shown with uncorrelated (inner error bars) and total (outer error bars) uncertainties. also shown are the nlo qcd predictions (hvqdis) [ ] with theory uncertainties indicated by the band. the beauty-production contribution is included in the cross section definition and is plotted separately. a customised nlo calculation (see text) is also shown. (d) differential d+ cross section as a function of p t (d +) down to pt (d +) = gev [ ]. cross section [ ] (entry in table ) measured down to pt (d +) = gev. the measurement was done in the d+ → k sπ+ decay channel. the presence of a neutral strange hadron in the decay resulted in a reasonable signal-to-background ratio even at very low transverse momentum of the d+ . the data were found to be described by the massive nlo qcd calculations within about two standard deviations. furthermore, parton-parton correlations have been studied in d∗ -tagged events [ ] (entry in table ). the conclusions are similar to those obtained from the respective photoproduction measure- ments. in general the massive qcd calculations provide a good description apart from the region of small ∆φ and very large |∆η| between the two leading jets in the event (not shown). (gev) jet te ( p b / g e v ) je t t / d e σ d - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep (gev) jet te d a ta / h v q d is . . ′ ′ ′ (a) jetη - . - - . . . ( p b ) je t η / d σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep jetη - . - - . . . d a ta / h v q d is . . ′ ′ ′ (b) figure : differential cross section for inclusive-jet production in beauty dis events as a function of e jet t (a) and η jet (b) [ ]. the data points are shown with statistical (inner error bars) and total (outer error bars) uncertainties. also shown are the nlo qcd predictions (hvqdis) [ ], corrected for hadronisation effects, with theory uncertainties indicated by the band. the dashed line shows the prediction from the rapgap mc generator [ ] scaled to the measured integrated cross section. inclusive lifetime tagging (entries , in table ) allowed the extension of the kinematic range of charm measurements up to e jet t = gev (not shown), which roughly corresponds to pt (d) ≈ gev, where the statistics of fully reconstructed charm mesons becomes poor. good agreement is again observed. figure shows the corresponding single-differential jet cross sections for beauty production in dis [ ] (entries and in tables and , respectively). the lifetime-tagging technique together with the reconstruction of the vertex mass were used to extract charm- and beauty-jet cross sections simultaneously. this measurement was selected since it has the highest statistical significance for beauty-quark production, as can be seen from the last column of table . the typical precision reached in the data is – % and is comparable to the theory uncertainties. the massive-scheme nlo qcd calculations provide a good description of the shape and normalisation of the measured cross sections. . double-differential cross sections the large collected data samples allowed measurements of double-differential heavy-flavour cross sec- tions, to study the correlations between various kinematic variables. the h collaboration has studied [ ] (entry in table ) the cross section as a function of xobsγ in different q ranges, complementing the measurements in the photoproduction regime discussed in section . . . it was shown that the amount of higher order contributions included in the massive nlo calculations, including topologies which would be called “flavour excitation” in the leading order picture, is enough to describe the data for different q , while the bgf-only component of the rapgap (d*)η - . - - . . . . . . . (d*)η - . - - . . . . . . . *(d*) < . gev t . < p * [n b /g e v ] t d p η / d σ d h (d*)η - . - - . . . . . (d*)η - . - - . . . . . *(d*) < . gev t . < p (d*)η - . - - . . . . . . . (d*)η - . - - . . . . . . . *(d*) < . gev t . < p (d*)η - . - - . . . . . . . (d*)η - . - - . . . . . . . *(d*) < . gev t . < p (d*)η - . - - . . . . . . . . (d*)η - . - - . . . . . . . . *(d*) < . gev t . < p h data hvqdis (mstw f ) hvqdis (ct f ) d* in dis figure : double-differential d∗ cross section as a function of p∗t (d ∗) and η(d∗) [ ]. the data points are shown with statistical (inner error bars) and total (outer error bars) uncertainties. nlo qcd calculation (hvqdis) [ ] with two different proton parton densities are compared to the data. theoretical uncertainties are indicated by the bands. monte carlo can describe the measurement for q > gev after rescaling, but fails to describe the shape observed in the data at lower q (not shown here). this is to be expected, since in this “photoproduction-like” region (see fig. ) the “flavour excitation” component will then be missing. using the full hera ii data sample, cross sections have been measured by h [ ] (entry in table ) as a function of the d∗ pseudorapidity in the laboratory frame, η(d∗), in bins of the d∗ transverse momentum in the γp centre-of-mass frame, p∗t (d ∗). figure shows a comparison of the massive nlo qcd predictions to the data. at large p∗t (d ∗), d∗ production in the backward region is very suppressed, while at low p∗t (d ∗) the η(d∗) distribution is rather flat in the phase space of the measurement. the massive-scheme nlo predictions provide a good description of the data. the predictions depend only very little on the proton pdfs used for the calculation. in most of the analyses summarised in tables and the double-differential cross sections in q and y or q and x were also measured. these measurements allowed dedicated studies of the inclusive heavy- flavour event kinematics which can be expressed in terms of the charm reduced cross sections, or of the charm contribution to the structure function f (see section . ). figure shows the combined double- differential d∗ cross sections as a function of q and y [ ]. massive-scheme nlo qcd predictions provide a good description of these cross sections in the full range in q between . gev and gev . ) d y ( n b /g e v /d q σ d y h and zeus - - - - - - < . gev . . gev t p (d*)| < . η| y figure : double-differential d∗ cross section as a function of q and y [ ]. the data points are shown with uncorrelated (inner error bars) and total (outer error bars) uncertainties. also shown are the nlo qcd predictions (hvqdis) [ ] with theory uncertainties indicated by the band. the beauty-production contribution is included in the cross-section definition and is plotted separately. the theoretical uncertainties decrease with increasing q . for q ∼< gev the theoretical uncertainties are larger than those of the measured cross sections. similar to the single-differential distributions shown in fig. , the theoretical uncertainties are dominated by the scale variations, the uncertainty on the charm-quark pole mass and the variation of the fragmentation model. a higher-order calculation with improved fragmentation model is needed to achieve a theoretical precision similar to the data. . proton structure functions and reduced cross sections the measured double-differential dis cross sections of heavy-flavour production as a function of q and y or q and x were used to extract the heavy-flavour reduced cross sections, σ qq̄ red , or the heavy- flavour contribution to the proton structure function f , f qq̄ , where q is either c or b. as discussed in section . , the inclusive double-differential cross sections of heavy-flavour production can be expressed in terms of σ qq̄ red or f qq̄ and f qq̄ l . in measurements of f qq̄ the small contribution arising from f qq̄ l was subtracted relying on theory, corresponding to a correction of up to %. the extraction from the measured cross sections requires an extrapolation from the experimentally accessible kinematic region in pt and η and a particular final state to the full phase space of heavy quarks. the extrapolation was done either using the massive-scheme nlo qcd calculations or lo+ps monte carlo simulations. since this procedure relies on the description of kinematic distributions by predictions, a non-negligible theoretical uncertainty was introduced. this additional uncertainty was estimated by varying the parameters in the calculations which affect the shapes of the kinematic distributions. the σ qq̄ red and f qq̄ values extracted from measurements performed with different experimental tech- niques and different detectors can be directly compared. such measurements are complementary to each other due to different dominant sources of systematics, mostly independent statistics and different kinematic coverage, resulting in somewhat different theoretical uncertainties due to extrapolation. for instance, for the σcc̄red measurements the dominant systematics in the h inclusive vertexing analysis (en- try in table ) is due to the treatment of the light-flavour component, while in the h d∗ hera ii measurement (entry in table ) the dominant systematics is due to the modelling of the tracking efficiency. the zeus analysis of charm semileptonic decays (entry in table ) has yet completely different systematics. therefore, a combination of measurements with such different techniques allows a significant reduction not only of statistical and uncorrelated but also of correlated systematic and extrapolation uncertainties. . . . . σ re d c c_ h vtx h d* hera-ii h d* hera-i zeus c → µ x zeus d* - zeus d* - zeus d zeus d+ h and zeus q = . gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev - - - q = gev - - - q = gev hera - - - x figure : combined reduced cross sections [ ] σcc̄red (filled circles) as a function of x for fixed values of q . the input data are shown with various other symbols as explained in the legend. the error bars represent the total uncertainty including uncorrelated, correlated and procedural uncertainties added in quadrature. for presentation purposes each individual measurement was shifted in x. figure shows a comparison of h and zeus measurements of the charm reduced cross sections as well as the milestone result of their combination [ ]. the combination accounts for correlations of the systematic uncertainties among the different input data sets. the individual σcc̄red measurements show good consistency, with a χ value of for degrees of freedom. the combined data are significantly more precise than any of the input data sets. figure also highlights the advantages of different tagging techniques: while d∗ has superior precision at low q due to better signal-to-background ratio, the inclusive vertexing analysis with lifetime tagging dominates at high q due to the larger accessible statistics. the final total precision of the combined charm reduced cross sections is % on average and reaches % at low x and medium q . this corresponds to a factor improvement over the most precise data set in the combination. . = . gev q . = gev q . = gev q . = gev q . = gev q . = gev q . = gev q . = gev q . = gev q . = gev q . = gev q . = gev q re dc c σ . . . . - - - - - - x - - - hera herapdf . h and zeus ) (gev q + . i b b f . . . . . . . . . . . - zeus vtx pb - zeus e pb - pbµzeus - +vtx pbµzeus - h vtx pb herapdf . abkm nnlo mstw nlo mstw nnlo cteq . nlo jr x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= figure : left: combined σcc̄red [ ] (filled circles) as a function of x for fixed values of q . the error bars represent the total uncertainty including uncorrelated, correlated and procedural uncertainties added in quadrature. the data are compared to the nlo predictions based on herapdf . [ ] in the tr standard gmvfns [ ]. the line represents the prediction using mc = . gev. the uncertainty band shows the full pdf uncertainty which is dominated by the variation of mc in the range . < mc < . gev. right: measurements of f bb̄ [ , , , , ] (various symbols) as a function of q at fixed values of x. the inner error bars are the statistical uncertainties, while the outer error bars are the statistical, systematic and extrapolation uncertainties added in quadrature. the data are compared to several nlo and nnlo predictions, including herapdf . [ ] in the tr standard gmvfns [ ]. the uncertainty band shows the full pdf uncertainty which is dominated by the variation of mb. entries , , , , , , , , , in table h charm and beauty cross section fraction - - - f q q_ x = . h data f cc _ f bb _ x = . mstw nnlo f cc _ f bb _ x = . - - - x = . x = . x = . - - - x = . x = . x = . - - - q / gev x = . q / gev x = . q / gev x = . - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - – - - - - - - - - - - - - - - - - - - - - - - - - - - – - - - - - - - - - - - - - - - - - - - - - - - - - - – - - - - - - - - - - - - - - - - - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - - - . . . - - - - - - q = . gev σ c c re d / σ re d q = gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev x q = gev q = gev x hera herapdf . - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - figure : fraction of charm and beauty contributions to the inclusive dis cross section as a func- tion of x and q [ , , ]. also shown (curves) is a gmvfns prediction by mrst [ ] and herapdf . . the dashed and dash-dotted lines are the asymptotic limits for charm and beauty from eq. ( ). additionally, new statistically independent measurements of charm production have been published (entries , and in table ), in particular the zeus d∗ measurement with hera ii data. in fig. the combined σcc̄red [ ] and individual measurements of f bb̄ (entries – , – , in table ) are compared to nlo and nnlo qcd predictions. the beauty measurements are all in good agreement with each other and the most precise data were obtained with inclusive lifetime tagging. the nlo qcd prediction in the gmvfns approach based on herapdf . [ ] is common for the two comparisons. the good agreement between these predictions and the heavy-flavour data shows that the gluon density, which in herapdf . is extracted from the scaling violations of f , is adequate for the description of these gluon-induced production processes. other gmvfns predictions were also compared to the combined charm reduced cross sections (not shown). the best description of the data was provided by predictions including partial o(α s) cor- rections, while predictions including o(α s) terms agreed well with the data and predictions including o(αs) have shown the largest deviations [ ]. the theoretical uncertainty for σcc̄red and f bb̄ increases at low q and is dominated by the mc variation. this indicates that the low-q data are sensitive to the value of the heavy-quark mass used in the calculation, which was exploited to extract the optimal mc values for different gmvfns schemes as well as to measure the running heavy-quark masses (see section . ). fig. shows the fraction of the heavy-flavour component in the total inclusive dis cross section: fqq̄ = f qq̄ /f and σ cc̄ red /σred . as expected, the heavy-flavour fractions increase with increasing q . for x ∼< . , the asymptotic limit is approached towards q ∼ m c ∼ gev for charm and q ∼ m b ∼ gev for beauty. the charm and beauty fractions in the high-q data come close to / and / , respectively, stressing the importance of the heavy-flavour component for the description of inclusive dis. the observed suppression of the heavy-flavour fractions for x ∼> . originates from the rising importance of the valence-quark contribution to the inclusive dis cross section in this kinematic domain. . summary large photon virtuality q provides an additional hard scale in the qcd calculations of heavy flavour production and allows probing the parton dynamics inside the proton more directly than photoproduc- tion. the dominant contribution to the charm and beauty cross sections arises from photon-gluon fusion. for q ≫ m q, where the photon virtuality is the dominant hard scale, the cross-section behaviour is similar to the one of the inclusive cross section for deeply inelastic scattering. at high q and low x, the naively expected charm and beauty contributions of / and / are asymptotically approached. for q ≪ m q, where the quark mass is the dominant hard scale, the cross section behaves essentially like photoproduction, i.e. the photon can be approximated to be quasi-real. nlo qcd predictions using zero-mass schemes (zmvfns) fail to describe the data in the vicinity of or below the so-called “flavour threshold” at q ∼ m q. nlo qcd predictions in the massive scheme (ffns) give a good description of heavy flavour production at hera over the complete accessible kinematic range. nlo predictions in variable flavour number schemes (gmvfns) are only available for inclusive quantitities, and perform about equally well. there is no indication for the need of resummation of ln q /m q terms at hera energies. in particular for charm, the uncertainties from qcd corrections beyond nlo and from the modelling of fragmentation are considerably larger than the experimental uncertainties of the measured cross sections. improved qcd calculations would therefore be highly welcome. measurement of qcd parameters, proton structure, and impact on lhc and other experiments so far the emphasis was on direct cross-section measurements from the hera data and on the compar- ison to and performance of different theoretical approximations for the perturbative qcd expansion. in this section the extraction of more fundamental qcd parameters and parametrisations will be dis- cussed, which are of direct relevance to all high energy physics processes and to the standard model of particle physics in general. . measurement of charm fragmentation functions and fragmentation fractions as outlined in section . , fragmentation fractions, i.e. the probability of a quark of a given flavour to form a specific final state hadron, and fragmentation functions, parametrising the fraction of the energy or momentum of the final state quark which will be taken by the final state hadron, are essential to relate theoretical qcd calculations at parton level to measurable hadronic final states. studies of the fragmentation process are based on a complete reconstruction of the final-state hadron. the statistics accessible at hera for fully-reconstructed beauty hadrons is extremely low due to the moderate beauty-production cross section and small branching ratios. on the other hand, hera is effec- tively a charm factory, with about charm events recorded to tape. therefore, only the fragmentation of charm quarks has been studied by h and zeus. charm fragmentation has been studied in both the dis and photoproduction regimes. a comparison between these results and e+e− measurements pro- vides a so far unique test of the fragmentation universality in the heavy-flavour sector for colour-neutral (electromagnetic) vs. coloured (strongly interacting) initial states. . . charm fragmentation function the explicit reconstruction of a d∗ meson in the final state has the optimal signal sensitivity of all fully reconstructed charm final states (cf. table and table ). thus, it has been used for studies of the non-perturbative charm fragmentation function (section . ). since the momentum of the charm quark is not measured in the detector, the fragmentation function is not a directly accessible quantity. it can be approximated either by jets to which a reconstructed d∗ meson is associated (for high-pt events) or by the overall energy flow in the event hemisphere around the d∗ (for production close to the kinematic threshold). parameters of the fragmentation function were extracted from the data by fitting corresponding predictions to the measured normalised differential cross sections as a function of zjet = (e + p)d (e + p)jet and zhem = (e + p)d ∑ hem(e + p) for the jet and hemisphere methods, respectively. the tuning of the fragmentation parameters was done based on monte carlo simulations [ , ] with similar jetset [ ] settings or on nlo qcd calculations using the same “heavy quark” definition and similar schemes for the cancellation of collinear and infrared divergences in photoproduction and dis [ , ]. due to the heavy quark masses most of these terms are not really divergent. nevertheless, events with “similar” topologies and large but almost cancelling weights are produced in correlated groups. zeus . . . . z /σ d σ /d z zeus ( pb- ) fmnr×c pyt had(kartvelishvili α= . + . - . ) fmnr×c pyt had(kartvelishvili α= . ) fmnr×c pyt had(kartvelishvili α= . ) (a) je t /d z σ d σ / . . . . je t /d z σ d σ / . . . . jet sample ± d* h data (parton level) = . + . αhvqdis = . - . αhvqdis jetz . . . . r . . (b) h e m /d z σ d σ / . . . . . h e m /d z σ d σ / . . . . . jet sample ± no d* h data (parton level) = . + . αhvqdis = . - . αhvqdis hem z . . . . r . . (c) h e m /d z σ d σ / . . . . h e m /d z σ d σ / . . . . jet sample ± no d* h data = . + . αrapgap = . - . αrapgap = . αrapgap hem z . . . . r . . (d) figure : the normalised d∗ cross sections as a function of z from the (a) zeus [ ] and (b), (c), (d) h [ ] analyses. the hard (b) and the threshold (c-d) regions are shown from the h measurement. the statistical (inner error bars) and the statistical and systematic uncertainties added in quadrature (outer error bars) are shown separately. the data are compared to the nlo qcd predictions (a-c) from hvqdis [ ] and fmnr [ ] as well as to the rapgap mc [ ] (d) based on the string fragmentation model. the parameter of the kartvelishvili fragmentation function was tuned to the data in each case. the h [ ] and zeus [ ] measurements were done in the dis and photoproduction regimes, respectively, utilising hera i data sets. the h experiment investigated both the high pt and the threshold regions, in order to cover the largest possible phase space, while zeus restricted the measure- ment to the high-pt regime, in order to reach small z values without strongly biasing the distributions, and in order to minimise perturbative fragmentation factorisation effects within the data set. this led to h selecting jets with e∗t > gev in the γ ∗p rest-frame and zeus cutting on et > gev for jets in the laboratory frame. figure shows the measured normalised differential cross sections as well as predictions after tuning of the fragmentation model. the extracted parameters of the fragmentation h [ ] zeus [ ] kinematics threshold high pt high pt ŝ, gev ∼ ∼ ∼ z method hem hem jet jet kartvelishvili [ ] α . + . − . . + . − . . + . − . . + . − . (χ /ndof) ( . / ) ( . / ) ( . / ) n.a. peterson [ ] ε . + . − . . + . − . . + . − . . + . − . (χ /ndof) ( . / ) ( . / ) ( . / ) n.a. table : parameters of fragmentation function extracted for the nlo qcd predictions by h and zeus. functions for the hvqdis and fmnr nlo calculations, which should also be applicable to the concep- tually similar mnr [ ] calculations in hadroproduction, are presented in table . a few observations can be made from the distributions: • as expected, due to the high quark mass, a charm meson retains a large fraction of the momentum of a charm quark. therefore, the charm fragmentation is much harder than that of light hadrons. • the fragmentation of charm quarks to d∗ mesons near to the kinematic threshold is harder than in the region away from the threshold (cf. fig. (b) and (c)). this can be qualitatively understood as a consequence of the fact that the phase space available for the production of additional particles is smaller near threshold. as a result, the fragmentation parameters extracted in the two kinematic regions are significantly different. this leads to the conclusion that the different kinematic regimes can not be described simultaneously within the framework of the independent fragmentation function. this is to be expected, since the nonperturbative phase space suppression is incompletely modeled in this approach. • nlo qcd calculations in conjunction with an independent fragmentation fail to describe the data close to the kinematic threshold: χ /ndof ≈ / (see fig. (c) and table ). however, in the same phase space mc simulations can be tuned to provide a reasonable description of the z distribution in the data: χ /ndof ≈ / (see fig. (d)). this might be due to the proper treatment of phase space effects in the mc, which are missing in the independent fragmentation approach used for the nlo predictions. • the peterson fragmentation provides a much worse description of the data than the kartvelishvili function. this has also been observed elsewhere [ ]. • the jet and hemisphere methods in the region where both are applicable, i.e. away from the threshold, yield similar results for the kartvelishvili parametrisation, while they remain some- what different in the peterson case. thus again, the kartvelishvili parameterisation seems to be preferred. for some recent measurements [ , , , , , , ], these results have been used explicitly to model the fragmentation for the comparison of theoretical predictions to the charm hera data (see section ) and for the extrapolation to the full phase space in the context of the extraction of the charm reduced cross sections (see section and section . ). this has shown that there are h [ ] zeus [ ] kinematics threshold high pt high pt ŝ, gev ∼ ∼ ∼ z method hem hem jet jet kartvelishvili α . + . − . . + . − . . + . − . n.a. (χ /ndof) ( . / ) ( . / ) ( . / ) n.a. peterson ε . + . − . . + . − . . + . − . . + . − . (χ /ndof) ( . / ) ( . / ) ( . / ) n.a. table : parameters of fragmentation function extracted by h and zeus for the fragmentation model in pythia with other parameter settings set to the default values. note, that also a set of fragmen- tation parameters was extracted by h [ ] for the aleph pythia tune [ ]. significant theory uncertainties due to fragmentation. a consistent phenomenological reanalysis of the h and zeus data is needed in order to resolve the differences observed in different kinematic domains, which originate from neglecting perturbative evolution and phase space effects, hopefully resulting in an important reduction of the related theory uncertainties. it is worth mentioning that the complete hera ii dataset, which has not yet been analysed in this context, is available in principle for this purpose. table shows the equivalent results extracted from lo+ps mcs using the “default” jetset settings as used e.g. by the pythia and rapgap mcs. in this case a perturbative evolution of the fragmentation function is partially included through the parton showering, and phase space corrections are applied. despite the poor χ , the peterson parameters extracted from the intermediate and high pt jet samples now agree with each other, as well as with the corresponding default parameter . extracted from e+e− collisions [ ]. this confirms the universality of the nonperturbative part of fragmentation. kartvelishvili parameters are unfortunately not available for all data sets and can hence not be compared. near threshold, even the mc model does not yield the same fragmentation parameters, and the χ is generally bad. this indicates that still not all threshold effects might have been fully accounted for. . . charm fragmentation fractions and ratios the fractions of c quarks hadronising into a particular charm hadron, f(c → d, Λc), have been measured by h and zeus in the dis [ , , ] and photoproduction [ , ] regimes. the measure- ments were done for d+, d , d∗+, d+s and Λc based on full reconstruction of the charm-hadron decays. the fragmentation fractions were extracted from integrated visible cross sections. the typical fidu- cial phase space of the charm hadrons was defined by pt (d, Λc) > gev and η(d, Λc) < . . the fragmentation fractions were extracted with the additional constraint that the sum of the fractions for all weakly-decaying open-charm hadrons (i.e. the ground states from the point of view of strong and electromagentic interactions) has to be equal to unity. this was done by a constrained fit in h [ ] and by an advanced procedure called equivalent phase space treatment in zeus [ ]. in addition to direct production, such experimentally measured fragmentation fractions include also all possible decay chains of excited charm hadrons. figure shows a compilation of all available charm fragmentation fraction measurements. the hera data are compared to an average of e+e− measurements [ , ]. to allow a direct comparison, c h a rm f ra g m e n ta tio n f ra ct io n s . . . . . . . pγ zeus hera ii pγ zeus hera i ep dis zeus hera i ep dis h -e+e ) d→f (c )+ d→f (c )+ d*→f (c )s d→f (c )cΛ →f (c figure : fractions of charm quarks hadronising into a particular charm hadron [ ]. measurements from hera are compared to the combined e+e− data. different hadron species are shown with different marker types. all measurements have been corrected [ ] to the decay branching fractions from pdg [ ]. the hera data reach very high precision, benefiting from a partial cancellation of some systematic uncertainties in the ratio. in particular, the recent zeus measurement [ ] is based on the full hera ii data sample and made use of the finalised tracking with lifetime tagging for d , d+ and d+s . this allowed to reduce both statistical and systematic uncertainties. the ultimate precision achieved with zeus hera ii data alone is fully competitive with the precision of the e+e− average from several experiments. all data from dis, photoproduction and e+e− collisions are in agreement within the high accuracy of the data. this demonstrates that the charm fragmentation fractions are independent of the production mechanism, and therefore supports the hypothesis of universality of heavy-quark fragmentation. the agreement between the fragmentation fractions has been checked quantitatively in the context of a combination [ ]. in addition to the fragmentation fractions, various charm fragmentation ratios were extracted: the ratio of the neutral to charged d-meson production rates, ru/d , the fraction of the charged d mesons produced in a vector state, p dv , and the strangeness-suppression factor, γs . figure shows a compar- ison of hera measurements [ , , , , ] with results obtained in e+e− collisions (numbers quoted in [ ] using average from [ ]) and hadroproduction by cdf [ ], alice [ , ] and at- las [ ]. also shown is a global average of p dv results from e +e− , photo- and hadroproduction [ ] , which also includes some e+e− , ep and cdf data shown separately. note, that the uncertainty of the average is driven by the π− – a result from the wa experiment [ ], which is quoted with statistical uncertainty only, i.e. treating all systematic uncertainties, including the branching-ratio uncertainty, as correlated between d+ and d∗+. the fragmentation ratios extracted from hera, e+e− and hadropro- the paper as well as other recent measurements [ , , ] report pv values, which correspond to the fraction of charged and neutral d mesons produced in the vector state. however the measurements rely on isospin symmetry assumption, which makes pv identical to p d v . . . . . . . u/dr v dp sγ zeus hera i dis zeus hera i php -e+e h hera i dis zeus hera ii php combinationdvp alice tev atlas tev cdf figure : fragmentation ratios ru/d , p d v , γs measured at hera and elsewhere [ , , , , , , , , , ]. different measurements are shown with different marker types. the error bars indicate the statistical and systematic uncertainties added in quadrature. the branching-ratio uncertainties are not shown due to the high degree of correlation between experiments and can be found in the original papers. the filled band shows the result of the p dv combination [ ]. duction data agree within experimental uncertainties. the ultimate precision achieved with the full hera ii data set is competitive with the most precise measurements in other experiments. vari- ous simple theory expectations can be tested against the data. the ru/d measurements are slightly above, but still in agreement within uncertainties, with the isospin invariance expectation of unity. the p dv measurements are smaller than the naive spin-counting expectation . and the string fragmentation prediction . [ , ]. excited charm mesons have also been studied with the zeus detector using the hera i [ ] and hera ii [ ] datasets. some parameters of the orbitally-excited charm states d ( ) ,+ with jp = + and d∗ ( ) ,+ with jp = + as well as charm-strange state ds ( ) + were measured. the masses and widths were found to be in good agreement between the two measurements and with the pdg average. the helicity parameters h for d ( ) and ds ( ) + were found to be in agreement with e+e− measurements. the measured d ( ) parameter was found to prefer a mixture of s and d waves in the decay to d∗+π−, although it is also consistent with a pure d wave. in addition, fragmentation fractions and ratios of branching ratios were extracted. for some parameters hera can provide important or even so far unique information. for example, the fragmentation fractions for the studied excited mesons are so far very poorly experimentally determined. the d ( ) + and d ( ) + fragmentation fractions were measured for the first time [ ]: f(c → d+ ) = . ± . (stat.)+ . − . (syst.)%, f(c → d∗+ ) = . ± . (stat.)+ . − . (syst.)%. . measurement of parton density functions the gluon pdf at low- and medium-x values is mostly constrained by the scaling violations of the inclu- sive structure function f . in contrast, heavy-quark production at hera provides a direct probe of the gluon momentum distribution in the proton through the γ∗g → cc̄ process. such direct measurements are complementary to the indirect approach. already the very early charm measurements were used to directly extract the gluon pdf, as was done by the h collaboration in [ ]. the gluon densities extracted from the charm data were found to be in agreement with the result of a qcd analysis of inclusive f measurements, although the charm measurement was limited by statistics. the recent combined charm dis data [ ] were also used in a qcd analysis [ ] together with the combined inclusive hera i dis cross sections [ ]. only the data with q > . gev were used in the analysis to assure applicability of pqcd calculations. the analysis was performed at nlo using the herafitter package [ , , ] and closely followed the herapdf . prescription [ ]. various implementations of the nlo gmvfns approach were used and the role of the value of the charm quark mass parameter (see section . ), mc, was studied. for each heavy-flavour scheme a number of pdf fits was performed to scan χ of the pdf fit as a function of mc. from the scan the optimal value, moptc , of the charm-quark mass parameter in a given scheme was determined by the minimum of the χ and the corresponding fit uncertainty was evaluated from the ∆χ = variation. the procedure is illustrated in fig. (a) which shows the fit to the inclusive dis data alone and together with σcc̄red . the inclusive dis cross sections alone only weakly constrain moptc , indicated by the shallowness of the χ (mc) distribution. the charm dis cross sections provide the required constraint to extract m opt c . additionally, for each gmvfns approach the model and parametrisation assumptions in the fits were varied one-by-one and the corresponding χ scan as a function of mc was repeated. the difference between moptc obtained with the default assumptions and the result of each variation was taken as the corresponding source of uncertainty. the dominant contribution to the uncertainty was found to come from the variation of the minimum q value for inclusive dis data used in the fit. figure (b) shows the χ distributions as a function of moptc obtained from fits to the inclusive hera i data and the combined σcc̄red for all variable-flavour-number schemes considered. all schemes yield similar minimal χ values, however at quite different values of moptc . the resulting values of m opt c are given in table together with the evaluated uncertainties, the minimal total χ values and the χ contribution from the charm data. the acot-full scheme provides the best global description of the inclusive and charm data together, while the rt optimised scheme yields the best description of the charm data alone. the fits in the s-acot-χ scheme result in a very low value of moptc compared to other approaches. since this scheme only includes a leading-order approximation of heavy-flavour production at the order considered here (see table ), effectively no distinction is made between pole or running mass. all nlo vfns predictions using corresponding moptc values for each scheme provide a similarly good description of the σcc̄red data [ ]. figure shows the pdfs extracted from the fit to the inclusive dis data alone and together with the σcc̄red data in the rt optimised vfns . a comparison of the extracted pdf uncertainties yields the following conclusions about the impact of the σcc̄red data [ ]: • the uncertainty on the gluon pdf was reduced, mostly due to a reduction of the parametrisation uncertainty due to the additional constraints that the charm data introduce due to the bgf process; this minimisation uncertainty is usually referred to as the “experimental” uncertainty in the herapdf context [ , ]. however, it can absorb some other sources of uncertainties, e.g. variations of pdf parametrisation. therefore, the more general term “fit uncertainty” is used here. similar observations were made with other schemes. [gev]cm . . . . ) c ( m χ hera-i inclusive charm + hera-i inclusive h and zeus rt standard . gev±= . opt cm (a) [gev] cm . . . . ) c ( m χ rt standard rt optimised acot-full χs-acot- zm-vfns opt c m h and zeus charm + hera-i inclusive (b) figure : (a) the values of χ (mc) for the pdf fit to the combined hera dis data [ ] in the rt standard scheme [ ]. the open symbols indicate the results of the fit to inclusive dis data only. the results of the fit including the combined charm data are shown by filled symbols. (b) the values of χ (mc) for the pdf fit to the combined hera inclusive dis and charm measurements [ ]. different heavy flavour schemes are used in the fit and presented by lines with different styles. the values of moptc for each scheme are indicated by the stars. . . . . - - - - herapdf . p herapdf . + charm x xf = gev q vxu vxd . )×xg ( h and zeus (a) . . . . - - - - herapdf . p herapdf . + charm x xf = gev q cx ux sx . )× (dx h and zeus (b) figure : parton density functions [ ] x · f(x, q ) with f = g, uv, dv, u, d, s, c for (a) valence quarks and gluon and for (b) sea anti-quarks obtained from the combined qcd analysis of the inclusive dis data and σcc̄red (dark shaded bands) in the rt optimised scheme as a function of x at q = gev . note that, somewhat confusingly but following common practice, here the variable x refers to xb in eq. , rather than to bjorken x. for comparison the results of the qcd analysis of the inclusive dis data only are also shown (light shaded bands). the gluon distribution function is scaled by a factor . and the xd distribution function is scaled by a factor . for better visibility. the total pdf uncertainties include fit, model and parametrisation uncertainties. scheme moptc χ /ndof χ /ndp [gev] σ nc,cc red +σ cc̄ red σ cc̄ red rt standard . ± . fit ± . mod⊕param⊕αs . / . / rt optimised . ± . fit ± . mod⊕param⊕αs . / . / acot-full . ± . fit ± . mod⊕param⊕αs . / . / s-acot-χ . ± . fit ± . mod⊕param⊕αs . / . / zmvfns . ± . fit ± . mod⊕param⊕αs . / . / table : the values of the charm mass parameter moptc as determined from the mc scans in different heavy flavour schemes [ ]. the uncertainties of the minimisation procedure are denoted as “fit”, the model, parametrisation and αs uncertainties were added in quadrature and are represented by “mod ⊕ param ⊕ αs”. the corresponding global and partial χ are presented per degrees of freedom, ndof, and per number of data points, ndp, respectively. • the uncertainty on the charm-quark pdf is considerably reduced due to the constrained range of mc. the mc variation was set to . < mc < . gev for the fit to the inclusive data only and was defined by the evaluated total uncertainties as given in table for the fit including the charm data; • the uncertainty on the up-quark sea pdf was correspondingly reduced, because the inclusive data constrain the sum of up- and charm-quark sea; • the uncertainty on the down-quark sea was also reduced because it was constrained to be equal to the up-quark sea at low x; • the uncertainties on the valence-quark and strange-quark sea pdfs were almost unaffected; • the central pdfs were not altered significantly and were found to be within the uncertainties of the pdfs based on inclusive data only. this reflects the good description of the charm data by the default pdfs (section . ). by now, the combined charm reduced cross sections [ ] have been used in qcd analyses by various pdf-fitting groups [ , , , , , , ]. they are an important ingredient to constrain the proton flavour composition (see also next section) and to stabilise its gluon content. the latter is especially important for higgs production at the lhc, for which the dominant process is gluon-gluon fusion via an intermediate top-quark loop. measuring this process precisely, in combination with a precise knowledge of the gluon content of the proton, allows the extraction of a precise measurement of the higgs-top yukawa coupling. instead focusing on the low-x range, the hera charm and beauty data have recently been used in conjunction with charm and beauty data from lhcb to constrain the gluon distribution down to x ∼ × − [ ]. this region is particularly relevant for the prediction of cross sections for processes occurring in cosmic ray interactions. . proton flavour composition and w/z/h production at lhc in the previous section it was outlined how the inclusion of charm data into gmvnfs pdf fits, and in particular the constraint on the charm quark mass parameter derived from these data, imposes constraints on the gluon content (relevant e.g. for higgs production) and on the flavour composition of the quarks in the proton. this, in turn, affects theoretical predictions for processes which are sensitive to this flavour composition, such as the production for w and z bosons at lhc. figure shows nlo predictions for w and z production at lhc for pdfs extracted in different heavy flavour schemes as discussed in section . , as a function of the charm quark mass parameter mc used in the pdf fit. for fixed mc, these predictions differ by about %. the dependence on mc is opposite to what one would naively expect (see also fig. ). a higher charm mass leads to less charm in the proton (fewer gluons split) but to a higher gluon density. this in turn increases the amount of u and d sea quarks in the proton, even more so since the total sea is constrained by the inclusive proton structure functions. the larger number of u and d quarks overcompensates the smaller number of c quarks and leads to an increase of the w and z cross sections as shown in fig. . the fit in fig. actually led to a smaller charm mass than the default, therefore the effect on the pdf was opposite. [gev]cm . . . . [ n b ] + w σ opt c m rt standard rt optimised acot-full χ s-acot- zm-vfns = tevs charm + hera-i inclusive h and zeus (a) [gev]cm . . . . [ n b ] - w σ opt c m rt standard rt optimised acot-full χ s-acot- zm-vfns = tevs charm + hera-i inclusive h and zeus (b) [gev]cm . . . . [ n b ] z σ opt c m rt standard rt optimised acot-full χ s-acot- zm-vfns = tevs charm + hera-i inclusive h and zeus (c) figure : nlo predictions for (a) w +, (b) w − and (c) z production cross sections at the lhc for √ s = tev as a function of mc used in the corresponding pdf fit [ ]. the different lines represent predictions for different implementations of the vfns. the predictions obtained with pdfs evaluated with the moptc values for each scheme are indicated by the stars. the horizontal dashed lines show the resulting spread of the predictions when choosing mc = m opt c . the stars in fig. indicate the cross section predictions for the optimal mass for each heavy flavour scheme, as extracted from the charm data in fig. (b). all predictions then coincide to within %, independent of the heavy flavour scheme used. this demonstrates that using the optimal mass for each scheme which best fits the hera charm data stabilises the flavour composition in the proton, and leads to a reduction of this contribution to the cross section uncertainty by about a factor . to minimise the uncertaities arising from the charm and beauty masses, for gmvfns schemes it is thus strongly recommended to use the optimal mass parameters as derived from the heavy-flavour structure-function data rather than a mass obtained from external considerations. a similar analysis for beauty, which remains to be done, will in addition yield experimental con- straints on the b pdf in the framework of -flavour pdfs for lhc, which are so far constrained by theory only. this in turn will be relevant e.g. for a future measurement of the higgs-b yukawa coupling from associated higgs-bb̄ production. . measurements of the charm-quark mass and its running the sensitivity of the hera reduced charm cross sections to the charm-quark mass, already partially studied in section . , can be used to measure the charm quark mass appearing in perturbative qcd, whose value depends on the renormalisation scheme within which it is being evaluated. the two mass definitions which are most commonly used are the pole mass and the ms running mass (section . ). since the ms mass is perturbatively better defined, recent charm mass measurements concentrate on this renormalization scheme. the ffns scheme (section . ) is most suited for this evaluation, since it fully accounts for mass effects without any additional free parameters. ffns calculations of the reduced cross section in this scheme exist at nlo and partial nnlo [ , ]. all results quoted in the following are obtained from these calculations unless otherwise quoted. the first determination of the ms charm-quark mass [ ], from a subset of d∗ charm data from the h collaboration, in which also the details of the theoretical framework are given, obtained mc(mc) = . ± . (fit) + . − . (scale) gev ( ) at nlo, and mc(mc) = . ± . (fit) + . − . (scale) ± . (theory) gev ( ) at partial nnlo, where the last term reflects a very conservative estimate of the evaluation of the uncertainties of the nnlo approximation. figure shows the comparison of predictions of the abkm group [ ], using the above mass values as central values, to the combined hera charm data [ ] discussed in section . , which have smaller uncertainties than the data used for the initial measurement. very good agreement is observed for both nlo and partial nnlo. the h and zeus collaborations have used a fit to these data (fig. (left)), using the kinematic region q > . gev , to obtain the nlo measurement [ ] mc(mc) = . ± . (exp) ± . (mod) ± . (param) ± . (αs) gev. ( ) this result has a slightly more elaborate evaluation of the uncertainties related to the data extrapolation as well as other model and parametrisation uncertainties, while it does not include uncertainties on the normalisation of the cross section predictions due to qcd scale variations. the same data where then used by the abm group and collaborators [ ] to reobtain similar evaluations, mc(mc) = . ± . (exp) + . − . (scale) gev ( ) at nlo, and mc(mc) = . ± . (exp) + . − . (scale) + . − . (theory) gev ( ) at partial nnlo. the smaller central nlo value and the smaller uncertainty are mainly due to the fact that the charm data from the lowest q bin were included. a correlated measurement of mc(mc) . . . . σ re d c c_ h and zeus q = . gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev q = gev - - - q = gev - - - q = gev hera abm nnlo ms  abm nlo ms  - - - x figure : combined reduced cross sections [ ] filled circles as a function of x for fixed values of q . the error bars represent the total uncertainty including uncorrelated, correlated and procedural uncertainties added in quadrature. the data are compared to predictions of the abm group at nlo (hashed band) and nnlo (shaded band) in ffns using the ms definition for the charm quark mass. ) [gev] c (mcm . . . χ ff (abm) h and zeus charm + hera-i inclusive . gev±)= . c (mcm figure : (left) the values of χ for the pdf fit [ ] to the combined hera dis data including charm measurements as a function of the running charm quark mass mc(mc). the ffns abm scheme is used, where the charm quark mass is defined in the ms scheme. (right) the values of mc(mc) obtained in the nlo and nnlo variants of the abm analysis [ ] with the value of αs(mz) fixed. the position of the star displays the result with the value of αs(mz) fitted. and the strong coupling constant [ ] was also obtained (fig. (right)). in particular for the nlo case, the correlation between mc(mc) and αs is non-negligible. they were also used by the cteq group [ ] to derive the ms mass in the context of the s-acot-χ vfns, using charm matrix elements to one-loop order in the massive part of the calculation. the result mc(mc) = . + . − . gev ( ) exhibits a larger uncertainty than the previous extractions due to the additional uncertainty from the variation of the (single) free parameter of this vfns scheme, and due to conversions between the pole and running masses in the extraction process. all these results from a predominantly space-like perturbative process are consistent with each other and with the world average [ ] mc(mc) = . ± . gev ( ) obtained from lattice qcd and time-like processes. this is a highly nontrivial triumph of qcd. some of the above measurements are now included in the latest world average [ ], and further improvements on both the experimental and theoretical sides have the potential to further improve the corresponding precision. in a recent preliminary result [ ] the same data have again been used to determine the actual scale dependence (‘running’) of the charm-quark mass in the ms scheme, according to eq. ( ). for this purpose, the charm data were subdivided into different q ranges, for which the charm mass was extracted separately at the scale < q > + m c, where < q > is the average of each range. the result is shown in fig. . this is the first explicit measurement of the scale dependence of the charm quark mass. [gev]µ ) [g e v ] µ( c m . . . . . . h and zeus preliminary hera (prel.) pdg with evolved uncertainty figure : measured charm mass mc(µ) in the ms running mass scheme as a function of the scale µ as defined in the text (black points). the red point at scale mc is the pdg world average [ ] and the band is its expected running [ ]. . measurement of the beauty-quark mass and its running using the same approach as outlined above for charm, the zeus collaboration has used a fit (fig. ) to the beauty reduced-cross-section data [ ] to extract the value of the beauty-quark ms running mass at nlo, mb(mb) = . ± . (fit) + . − . (mod) + . − . (param) + . − . (theo) gev, ( ) . . . . . . . . . . . . . . . . . . . . . x - - - x - - - x - - - b b r σ . . . . . . . . . - zeus pb = . gev (best fit) b qcd fit, m = . gev b qcd fit, m = . gev b qcd fit, m zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : reduced beauty cross section (filled symbols) as a function of x for seven different values of q [ ]. also shown are the results of a qcd fit for different values of the ms running mass mb(mb). where the theoretical uncertainty is dominated by the scale variation uncertainty. this is the first such extraction from hera data, and agrees well with the world average [ ] mb(mb) = . ± . gev. ( ) figure shows this result, translated to the scale m b, compared to the pdg value and its expected running and to values extracted from lep data at the scale mz. the expected running of the ms beauty-quark mass is confirmed. this is a nontrivial test of the basics of qcd. [gev]µ ) [g e v ] µ( b m . . . zeus pdg with evolved uncertainty zeus delphi -jets delphi -jets nlo aleph opal sld figure : measured beauty mass mb(µ) in the ms running mass scheme as a function of the scale µ from hera [ ] and lep [ ] data. the red point at scale mb is the pdg world average [ ] and the band is its expected running [ ]. . summary heavy flavour physics at hera yields many results which are of interest for particle physics in general. the usage of hera as a “charm factory” generates world-class information on charm fragmentation functions and fragmentation fractions and allows tests of the fragmentation universality. the constraints on pdfs from charm data, and to a lesser extent also from beauty data, help to reduce uncertainties for important cross sections at lhc, such as heavy flavour, w/z and higgs production. constraints on the latter are important for the measurement of the higgs yukawa couplings. more directly, the charm and beauty dis data have been used to extract well defined measurements of the charm- and beauty-quark masses, which enter the world average. the running of the charm-quark mass has been measured for the first time ever. by comparing with lep data, the running of the beauty quark mass has also been confirmed. in general, the good agreement of qcd predictions with the data support the applicability of the hera results to all particle physics applications for which they might be directly or indirectly relevant. summary and outlook charm and beauty production at hera are a great laboratory to test the theory of heavy flavour pro- duction in the framework of perturbative qcd and to measure some of its parameters. the occurrence of different possibilities to treat the heavy quark masses in the pdf, matrix element and fragmenta- tion parts of the calculation introduces a significant level of complexity into the corresponding qcd calculations, in addition to the usual scheme and scale choices. confronting such different choices with data can be helpful to understand the effects of different ways to truncate the perturbative series and to evaluate their impact on the measurement of fundamental parameters, both at hera and at other colliders. hera was the first and so far only high energy ep collider. the heavy flavour results discussed in this review were obtained with the h and zeus detectors which were well suited for the detection of heavy flavoured particles. adding the luminosities from the two collider experiments, a total luminosity of about fb− was collected. the availability of many different charm and beauty tagging methods allows results to be obtained through several different final states with different systematics. in addition to the statistical benefit from combining different samples, such combinations also profit from cross calibrations of the systematics from different methods and experiments. due to the high top mass, the only top final state which might have been detectable at hera is single top production with non-standard-model couplings. no signal is seen, and the coupling limits derived are competitive. the charm (beauty) quark masses provide semi-hard (hard) qcd scales which allow the succesful application of perturbative calculations over the complete phase space. however, these masses also compete with other, often even harder perturbative scales. total cross sections for charm photoproduc- tion and the total cross section for beauty production (including photoproduction and deeply inelas- tic scattering) are reasonably described by perturbative calculations at next-to-leading order (nlo). single-differential cross sections already provide a good handle to test the applicability of different qcd approximations, although the theoretical uncertainties are mostly much larger than the experimental ones. the theory predictions agree with the data up to the highest accessible transverse momenta or photon vitualities, showing no indications that final state resummation corrections are needed for massive calculations in the hera kinematical domain. double-differential cross sections, in particu- lar those including jets, reveal a partial failure of the massive scheme nlo predictions for kinematic observables which would need final states with four or more partons in the calculation. although statistics and therefore precision is higher for photoproduction, qualitatively very similar conclusions are obtained for photoproduction and deeply inelastic scattering (dis). the nlo calculations in the massless scheme, where available, do mostly not provide a better description for the observables, and clearly fail for some dis observables. the lo+ps mcs pythia and herwig, which are often used for acceptance corrections, are able to describe all topologies reasonably, often even very well. the cascade kt-factorisation mc performs somewhat less well on average. in dis, the large photon virtuality q provides an additional hard scale in the qcd calculations of heavy flavour production and allows probing the parton dynamics inside the proton more directly than in photoproduction. the dominant contribution to the charm and beauty cross sections arises from photon- gluon fusion. for q ≫ m q, where the photon virtuality is the dominant hard scale, the cross-section behaviour is similar to the one of the inclusive cross section for deeply inelastic scattering. at high q and low x, the naively expected charm and beauty contributions of / and / are asymptotically approached. nlo qcd predictions in the massive scheme (ffns) give a good description of heavy flavour production at hera in dis over the complete accessible kinematic range. nlo predictions in variable-flavour-number schemes (gmvfns) are only available for inclusive quantities, and perform about equally well. in particular for charm, the uncertainties from qcd corrections beyond nlo and from the modelling of fragmentation are considerably larger than the experimental uncertainties of the measured cross sections. improved qcd calculations would therefore be highly welcome. heavy flavour physics at hera yields many results which are of interest for particle physics in general. the usage of hera as a “charm factory” generates world-class information on charm frag- mentation functions and fragmentation fractions and allows tests of the fragmentation universality. the constraints on proton parton distribution functions (pdfs) from charm and beauty data help to reduce uncertainties for important cross sections at the lhc, such as heavy flavour, w/z and higgs produc- tion. constraints on the latter are important for the measurement of the higgs yukawa couplings. more directly, the charm and beauty dis data have been used to extract well defined measurements of the charm- and beauty-quark masses, which enter the world average. the running of the charm-quark mass has been measured for the first time ever, and the running of the beauty quark mass has been confirmed. in general, the good agreement of qcd predictions with the hera data support the applicability of the qcd results derived from these data to all particle physics applications for which they might be directly or indirectly relevant. some of the most important hera heavy flavour results have been obtained during the last - years. even years after the end of data taking the potential of the hera heavy flavour data has still not been fully used in all cases, so there is room for significant further improvements, in particular also on the theory side, hoping e.g. for differential nnlo calculations in ep collisions, similar to those which have recently started to appear for the pp case. acknowledgements this review is a partial summary of the work of perhaps a thousand technicians, engineers and physicists for more than two decades. it is our great pleasure to thank the many collegues who have contributed to the results presented here. we thank o. kuprash and l. schalow for 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[ ] delphi collaboration, j. abdallah et al., eur. phys. j. c ( ) [arxiv: . ]; and references therein. introduction theory of heavy-flavour production at hera . hera kinematic variables and phase space . perturbative qcd calculations . heavy-quark production at hera in ``leading order'' . quark-mass definition . the zero-mass variable-flavour-number scheme . the massive fixed-flavour-number scheme . the general-mass variable-flavour-number scheme . proton structure functions in dis . qed corrections . fragmentation . choice of renormalisation scale . summary the hera collider and experiments . hera . h and zeus detectors . event reconstruction . summary charm and beauty detection at hera . charm tagging using full reconstruction of charm hadrons. . heavy-flavour tagging with lepton + ptrel . charm and beauty with inclusive lifetime tagging . charm and beauty with double tagging . summary search for single top-quark production charm photoproduction . d* inclusive measurements . . charm total cross sections . . d* single-differential cross sections . . d* double-differential cross sections . inclusive measurements using other tagging methods . studies with a d* and one other hard parton . parton-parton-correlation studies in charm-tagged events . . xobsstudies . . azimuthal correlations . . study of hard-scattering angle cos* . summary beauty photoproduction . total cross section for beauty production . single-differential cross sections . measurements of b" b and jet-jet correlations . summary charm and beauty production in dis . production mechanism . single-differential cross sections . double-differential cross sections . proton structure functions and reduced cross sections . summary measurement of qcd parameters, proton structure, and impact on lhc and other experiments . measurement of charm fragmentation functions and fragmentation fractions . . charm fragmentation function . . charm fragmentation fractions and ratios . measurement of parton density functions . proton flavour composition and w/z/h production at lhc . measurements of the charm-quark mass and its running . measurement of the beauty-quark mass and its running . summary summary and outlook the economic journal,  (no�ember), –. # royal economic society . published by blackwell publishers,  cowley road, oxford ox jf, uk and  main street, malden, ma , usa. o n t h e r o b u s t n e s s o f b e h a v i o u r i n e x p e r i m e n t a l ‘ b e a u t y c o n t e s t ’ g a m e s * john duff� and rosemarie nagel we report and compare results from several different versions of an experimental interactive guessing game first studied by nagel (), which we refer to as the ‘ beauty contest ’ game following keynes (). in these games, groups of subjects are repeatedly asked to simultaneously guess a real number in the interval [, ] that they believe will be closest to } times either the median, mean, or maximum of all numbers chosen. we also use our experimental data to test a simple model of adaptive learning behaviour. it might have been supposed that competition between expert pro- fessionals, possessing judgement and knowledge beyond that of the average private investor, would correct the vagaries of the ignorant individual left to himself. it happens, however, that the energies and skill of the professional investor and speculator are mainly occupied otherwise. for most of these persons are, in fact, largely concerned, not with making superior long-term forecasts of the probable yield of an investment over its whole life, but with foreseeing changes in the conventional basis of valuation a short time ahead of the general public. – john maynard keynes (, p. ). as keynes observed, much of professional investment behaviour is concerned with attempting to keep one step ahead of average behaviour. the average investor, or in keynes’ view, ‘ the ignorant individual left to himself ’, is unlikely to disappear, as it is precisely the behaviour of this type of investor that market professionals are attempting to forecast. in this paper we study the evolution of behaviour in a number of market-type ‘ beauty contest ’ games involving groups of experimental subjects." the behaviour of the subjects in these games has much in common, in flavour if not specifics, with keynes’ insight regarding the behaviour of investors in financial markets. we study variations on the ‘ beauty contest ’ game that has been conducted experimentally and analysed previously by nagel (), stahl () and ho et al. (). in the version of the game studied in these papers, groups of * this paper was written while nagel was a post-doc in the department of economics at the university of pittsburgh. we thank colin camerer, ido erev, nick feltovich, al roth, dale stahl, nick vriend and two anonymous referees for helpful comments and suggestions. duffy acknowledges support from the u.s. national science foundation. the data from the experiments reported in this paper are available on request from the authors. " the beauty contest analogy is also due to keynes (, p. ), who likened professional investment activity to newspaper beauty contests of the time where readers were asked to choose the six prettiest faces from among  photographs with the winner being the person whose preferences were closest to the average preferences. the reasoning process that keynes describes for this beauty contest game applies to the p-mean, p-median and p-maximum games described below, where p . for p ¯ , as in keynes’ example, different levels of reasoning cannot be distinguished and therefore it is necessary to choose p . see also nagel () and ho et al. () who also make use of keynes’ beauty contest metaphor. nagel () refers to the ‘ beauty contest ’ game as a guessing game. [  ]  subjects are repeatedly asked to simultaneously guess a real number in the interval [, ]. the winner is the person(s) whose guess is closest, in absolute value, to p times the mean of all numbers chosen, where p is some pre- announced fraction (p ). the winner of each round wins a fixed prize and the other participants receive nothing. if there are several winners, the prize is divided equally among them. for the case where  % p ! , iterated elimination of dominated strategies leads to a unique nash equilibrium in which all players announce . for the case where p " , and a guessing interval of [ε, ], ε " , the unique nash equilibrium is for all players to announce . when p ¯ , the nash equilibrium is no longer unique ; any number in the guessing interval is a potential nash equilibrium provided that all players announce the same number.# we shall focus our attention on the case where  % p ! . nagel () and ho et al. () report that after several repetitions of the p-mean game where  % p ! , the mean of all chosen numbers is consistently and significantly greater than zero, though there is some tendency for the mean to decline over time. in this paper we test the robustness of these findings for the p-mean game by considering two additional experimental treatments and by playing the game for a longer number of rounds. in the two new treatments, we change the order statistic of the game, replacing the mean with either the median or the maximum. we shall refer to the three different games according to the order statistic used ; for example, the p mean game will be referred to simply as the ‘ mean ’ game. for  ! p % " # , both the ‘ median ’ and ‘ maximum ’ games are dominance solvable and have the same equilibrium as the mean game, namely that all players announce zero.$ we chose to examine how players behave in the median and maximum games in comparison with the mean game, because these two additional treatments assign very different weight to ‘ extreme guesses ’ – guesses that lie in the tails of the sample distributions. in the median game, these extreme guesses do not affect the value of the median as much as they affect the value of the mean, since the median is an unbiased measure of central tendency. consequently, we hypothesise that by comparison with the mean game, players in the median game should be relatively less concerned about extreme guesses ; they will therefore be capable of achieving greater coordination and will be relatively closer to the equilibrium strategy where all announce zero at the end of the game. by contrast, in the maximum game, the behaviour of the outlier – the player choosing the highest number – is the primary concern of all players. since a single player determines the winning number, we expect that by comparison with the mean or median games, subjects in the maximum game will have achieved relatively less coordination, and will therefore be relatively # the p ¯  case is similar to the coordination game studied by van huyck et al. (). $ for " # ! p ! , the maximum game has no pure equilibria and for p ¯ " # , the equilibrium where all choose zero is a weak equilibrium. for p % " # , the numbers in [p, ] are weakly dominated by p. by iterated elimination of weakly dominated strategies,  is the only non-excluded strategy. for the two player game, zero is a weakly dominant strategy. # royal economic society                    [         ]                   further from the equilibrium strategy where all announce zero at the end of the game. one interpretation of our experiment is that it provides a test of the importance of framing effects in group decision making.% since all three treatments have the same equilibrium, it is clearly the framing of the objective of each guessing game treatment that must be responsible for any differences in observed behaviour across the three treatments. however, we believe that our three treatments also have important economic interpretations as well. as we have indicated, the three treatments provide a nice spectrum of environments that may be more or less conducive to the achievement of coordination by groups of economic agents. in this respect, our experiment is similar to the various coordination game environments that have been studied by van huyck et al. (, ). alternatively one might view the different environments as giving more or less weight to ‘ fundamental ’ or ‘ speculative ’ behaviour. for example, one can view the median game environment as one in which players may be relatively more concerned with ‘ market fundamentals ’ such as the fraction p or the previous period’s market average, and relatively less concerned with speculating about the future actions of other players. by contrast, one can view the maximum game environment as one in which players are perhaps relatively less concerned with such market fundamentals, and relatively more concerned with speculating about the future actions of those individuals who choose high numbers – keynes’s ‘ ignorant individuals ’. another purpose of our experiment was to consider the performance of a simple theory of adaptive learning behaviour – learning direction theory – in explaining the behaviour of players from period to period across the three different treatments. according to learning direction theory, the direction of a player’s action from the previous round to the current round can be explained by the player’s previous round action in relation to the ex-post optimal action. this theory of learning behaviour was first proposed by selten and stoecker () and has been applied by selten and buchta (), nagel () and others. in particular, nagel (), stahl () and ho et al. () have all considered learning direction theory as a way of explaining the behaviour of subjects in the mean game, and so it seemed natural to consider the explanatory power of learning direction theory for the median and maximum games as well. while learning direction theory is not easily generalised, stahl () and camerer and ho () have formulated more general learning models that incorporate the basic idea of learning direction theory.  .                       :                          nagel () suggested the following ‘ descriptive model ’ of how subjects might play the mean game. in round , when there is no information about the % for an introduction to the issue of framing and some empirical examples, see e.g. tversky and kahneman (). # royal economic society   behaviour of other players, subjects reason that a plausible reference or focal point is , which is the midpoint of the guessing interval [, ], and a good candidate for the mean if one believes that the first round guesses will be uniformly distributed over [, ]. while it is assumed that all players have the same initial reference point, players may differ according to the depth of reasoning they employ when determining their guesses for each round of the game. denote the guess of player i in round t by g i (t). player i’s depth of reasoning in round t (the player’s iterated best reply) is defined as the value of d that solves g i (t) ¯ m(t®) pd, where  ! p !  is the given fraction and m(t®) denotes the mean from the previous round ; for t ¯ , m() ¯ , the hypothesised initial reference point. to simplify the analysis we will follow nagel () and group the continiuous d values into discrete categories based on neighbourhood intervals centred on certain integer values : d ¯ , ,  and . these neighbourhood intervals have the boundaries m(t®) pd+"# and m(t®) pd−"#. values for d below the lower bound for the d ¯  category are lumped together into a single category, referred to as d ! , as are values for d above the upper bound for the d ¯  category, referred to as d " . note that the nash equilibrium prediction requires that all players employ a depth of reasoning d ¯ ¢. using the six neighbourhood intervals, d ! , d ¯ , , ,  and d " , nagel () observed that approximately  % or more of players’ guesses in the first four rounds of the mean game could be categorised as either d ¯ , ,  or .& a potential difficulty with the mean game is that the mean is a biased measure of central tendency ; it gives relatively more weight to extreme, ‘ outlier ’ observations. this bias may have affected the behaviour of subjects in the mean game treatment. indeed, one observes that in the final rounds of nagel’s () " # - and # $ -mean game experiments, a few players, perhaps out of frustration, decided to choose very large numbers – numbers that were significantly larger than the numbers they chose in earlier rounds. similarly, in the " # -mean game sessions that we replicated for this paper, there were some players in the third and fourth rounds who chose larger numbers than they chose in either the first or second rounds. with sample sizes of – players, these large final round deviations can and do affect the value of the mean. subjects who recognise this possibility may want to avoid using too great a depth of reasoning when determining their guesses. thus, while subjects may be capable of higher depths of reasoning – even at infinite depth of reasoning – the use of the mean as the order statistic may serve to alter their behaviour so that it appears as though they are employing a more shallow depth of reasoning than they might otherwise & see also stahl () who develops a parametric approach that can be used to test the validity of this depth of reasoning approach. ho et al. () obtain similar results in the initial rounds of the mean game using smaller group sizes of three or seven subjects. # royal economic society                    [         ]                   choose. this observation serves as our motivation for comparing behaviour in the mean game with behaviour in the median and maximum games.   .                   to test our conjectures regarding behaviour in the different treatments, we conducted  experimental sessions. we conducted three sessions each of the " # - median, " # -mean and " # -maximum games for four rounds, and one session of each of these three games for ten rounds. for each session we recruited a group of – subjects from the undergraduate population at the university of pittsburgh (for a total of  subjects). subjects were only allowed to participate in a single experimental session ; no subject had any previous experience with any of the games. each subject was guaranteed a show-up fee of $. in addition, the winner of each round was paid $. if there was more than one winner, the $ prize was divided equally among the winners. we explained to subjects in the mean and median games how the mean and median values are determined. subjects were isolated from one another and were not allowed to communicate with each other. they were informed in advance how many rounds would be played. subjects wrote their guesses for each round on cards. the cards were then collected and the numbers were read aloud as well as written on a black board without identifying any player. depending on the game, subjects were informed of the median, mean or maximum, " # times the median, mean or maximum, and the winning number(s) – the number(s) closest to " # the median, mean or maximum. once this information had been revealed, the next round of the game was begun.    .                    fig.  shows the cumulative frequencies with which numbers in the [, ] guessing range were chosen in the first four rounds of each treatment using pooled data from all sessions of a treatment. we observe that by the fourth round of all median games,  % of guesses are less than ten while by the fourth round of all maximum games, only  % of guesses are less than ten ; in the mean games,  % of guesses are less than ten by the fourth round. first round beha�iour in the first round of every session, no subject chose zero. at the other extreme, the percentage of first round guesses that were weakly dominated (i.e. greater than ) was  % in all median games,  % in all mean games and  % in all maximum games. to examine whether there were any differences in first round behaviour across treatments, we pooled data for all four sessions of a given treatment. we # royal economic society   · · · · · · guessing range c u m u la ti ve f re q u en cy round round round round · · · · · · guessing range c u m u la ti ve f re q u en cy round round round round · · · · · · guessing range c u m u la ti ve f re q u en cy round round round round / median game / mean game / maximum game fig. . cumulative frequency of guesses in rounds – " # median game. then conducted non-parametric, robust rank order tests of the null hypothesis that there is no significant difference in the distribution of first round guesses between the mean and median games, the mean and maximum games, and the median and maximum games.' we find that we cannot reject the null hypothesis of no difference in the distribution of first round guesses between the mean and median games (p ¯ ±). however, we can reject this same null hypothesis in comparisons between the maximum and mean games (p ¯ ±) and between the maximum and median games (p ¯ ±) in favour of the ' see siegel and castellan (, pp. –) for a description of the robust rank order test used here. # royal economic society                    [         ]                   median game ( ) mean game ( ) maximum game ( ) maximum game ( ) game and (initial reference point) d < d = d = d = d = d > c u m u la ti ve f re q u en cy · · · · · · · · · fig. . classification of first round choices according to depth of reasoning for given initial reference points. alternative hypothesis that first round guesses are higher in the maximum game than in either the mean or median games. in an effort to explain these differences, we classified subjects’ first round choices according to the six discrete depth of reasoning categories discussed in section i. for the mean and median games we used the hypothesised initial reference point of  while for the maximum game we considered both  and  as initial reference points. from a cognitive point of view,  is probably the more plausible initial reference point for the maximum game since it is the upper bound to the guessing interval and subjects are specifically instructed to choose the number they believe will be closest to " # times the maximum.( fig.  plots the relative frequency with which the six categories were observed in the first round of the three treatments. we see that with  as the initial reference point,  % of first round choices in the mean and median game are categorised as either d ¯  or d ¯ . similarly, with  as the initial reference point,  % of first round choices in the maximum game can be categorised as either d ¯  or d ¯  ; if  is used as the initial reference point, only  % of first round choices in the maximum game can be categorised as either d ¯  or d ¯ . if one assumes that the initial distribution of depths of reasoning (d values) should be roughly the same across all three treatments, then the appropriate first round reference point would appear to be  in the ( nagel () and stahl () found that for different p values in the mean game the most plausible initial reference point was always . see also ho et al. () who estimate the initial reference point for the mean game using nagel’s () data. # royal economic society   table  percentage change in the median guess from round � to round � game}session percentage change in median guess " # -median game session  ®± session  ®± session  ®± session  ®± " # -mean game session  ®± session  ®± session  ®± session  ®± " # -maximum game session  ®± session  ®± session  ®± session  ®± m ed ia n g u es s (l og s cl ae ) · e + · e + · e + · e – · e – · e – · e – · e – · e – rounds / median game / mean game / maximum game fig. . the path of the median guess over  rounds of each game. mean and median games, and  in the maximum game. this higher initial reference point in the maximum game may account for the statistically significant difference that was observed in the distribution of initial guesses between the maximum game and the mean and median games. # royal economic society                    [         ]                   table  classification of choices according to depth of reasoning relative frequencies* round           (a) " # -median game session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d !  ± ± ± ± ± ± ± ± ± ± all sessions d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± (b) " # -mean game session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± d ¯  ± ± ± ± # royal economic society   table  (cont.) relative frequencies* round           d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d !  ± ± ± ± ± ± ± ± ± ± all sessions d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± (c) " # -maximum game session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± session  d "  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d ¯  ± ± ± ± ± ± ± ± ± ± d !  ± ± ± ± ± ± ± ± ± ± all sessions d "  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d ¯  ± ± ± ± d !  ± ± ± ± * modal frequencies are underlined. # royal economic society                    [         ]                   beha�iour o�er time in table  we report the percentage change in the median guess from the first to the fourth round of each individual session. we see that the percentage changes in the median guess from round  to round  are generally largest (in the direction of zero) in the median game sessions, and generally smallest in the maximum game sessions in accordance with our hypotheses. to test whether these percentage changes are significantly different from one another, we again performed a robust rank order test using the data of table . we find that the percentage changes in the median guess from rounds  to  are significantly larger in the median game than in the mean game (p ¯ ±). similarly, we find that the percentage changes in the median guess over rounds – are significantly larger in the mean game than in the maximum game (p ¯ ±). it follows that the percentage changes in the median guess over rounds – are also significantly larger in the median game as compared with the maximum game (p ¯ ±). these differences in the evolution of the median guess over time appear to persist beyond the first four rounds ; fig.  plots the path taken by the median guess in each of the single ten-round sessions that we conducted for each game. we see that at the end of ten rounds, the median guess in the median game is closest to the nash equilibrium prediction while the median guess in the maximum game remains furthest from the equilibrium outcome. to examine the reasoning process that subjects followed in rounds  to , we can use the same classification scheme for depth of reasoning that was used for the first round guesses. now, however, we use as the reference point, the previous period’s mean, median or maximum, depending upon the treatment. that is, player i’s depth of reasoning in rounds t ¯ , , … ,  is the value of d that solves g i (t) ¯ m(t®) pd, where m(t®) now represents the previous period’s announced mean, median or maximum value. tables  (a)–(c) report for the median, mean and maximum game treatments, the relative frequency of choices in the neighbourhood categories of d ! , d ¯ , , ,  and d " . we see that across all three treatments, the modal depth of reasoning categories (which are underlined) in rounds – are typically d ¯  or d ¯ , as was the case for the first round. indeed, over the first four rounds of every session, the majority of choices lie below the d ¯  category. if we consider the percentage of all guesses that are categorised as being either d ¯  or d "  in each round we cannot reject, using rank order tests at the  % significance level, the null hypothesis of no significant difference in these percentages between any two of the three treatments. thus, like nagel (), we do not find any significant evidence that subjects employ increasing depths of reasoning over the first four rounds of the ‘ beauty contest ’ game. however, when we consider the ten round sessions, there is some evidence that players do employ greater depths of reasoning over time. this is most apparent in the final four rounds (–) of # royal economic society   the " # -median game, where we observe that all choices are classified as d ¯  or higher. by contrast, there is no evidence of increasing depth of reasoning in the longer, ten-round version of the maximum game. these findings suggest that if subjects are given enough time, and an environment where outliers have little influence, they may indeed learn to employ greater depths of reasoning.   .                        following nagel (), we examine whether players’ behaviour from round to round follows the predictions of a simple adaptive learning scheme known as ‘ learning direction ’ theory (see selten and stoecker ()). this theory suggests that players adjust their decisions from round to round using an ex-post reasoning process based on the previous period’s outcome. in the case of the ‘ beauty contest ’ game, if player i’s guess in the previous round, g i (t®), was higher than the winning number in the previous round, p¬m(t®), the theory predicts that player i will employ a greater depth of reasoning in round t by decreasing his adjustment ratio, g i (t) m(t®) , given the current reference point of m(t®), i.e. g i (t®) " p¬m(t®) g i (t) m(t®) ! g i (t®) m(t®) . analogously, if player i’s guess in the previous round was lower than the winning number in the previous round, then the theory predicts that player i will employ a more shallow depth of reasoning when forming his guess for the current round by increasing his adjustment ratio given the current reference point of m(t®), i.e. g i (t®) ! p¬m(t®) g i (t) m(t®) " g i (t®) m(t®) . nagel () found that a majority of players’ actions in the first four rounds of the p-mean game were consistent with the predictions of learning direction theory. while there are a number of other learning models that could be applied to the data obtained from our experiments (e.g. naı$ ve, adaptive or bayesian learning models), our aim in this paper is not to test all of these competing theories, but rather to examine whether learning direction theory continues to be a good predictor of subject behaviour when the order statistic of the ‘ beauty contest ’ game is changed or when the number of rounds played of the game is increased.) ) see stahl () for an econometric analysis of how well learning direction theory compares with other learning theories using nagel’s () data for the p-mean game. see also ho et al. () who compare the performance of learning direction theory with other theories of player behaviour using data collected from -round experimental sessions of the mean game involving small groups of subjects. # royal economic society                    [         ]                   table  (a) reports the frequencies of adjustment behaviour over rounds – using pooled data from all four sessions of each treatment. the data are categorised according to whether players’ previous round guesses were greater than or less than the winning number and also according to whether players increased or decreased their adjustment ratios in the subsequent round. if in the current round, a player’s guess turns out to have been greater than (less than) " # the reference point, learning direction theory predicts that in the following round, the adjustment ratio g i (t) m(t®) , will be decreased (increased) relative to subject’s previous adjustment ratio. the frequencies of behaviour that are consistent with the predictions of learning direction theory are noted in boldface type and the total frequency of behaviour that is consistent with learning direction theory (ldt) is also noted. we see that with a single exception (the transition from rounds  to  of the " # -median game), an average of more than  % of transition behaviour is consistent with the predictions of learning direction theory using pooled data for all three treatments. this finding is consistent with nagel’s () finding for the p-mean game. a particularly interesting finding in table  (a) is that players’ depths of reasoning do not necessarily increase over time. in the first few rounds of the maximum game we see that a majority of players find that they are consistently below " # the reference point, and subsequently, most of these players choose to employ a more shallow depth of reasoning over time (they increase their adjustment ratio upwards). this type of behaviour is consistent with the predictions of learning direction theory, but runs counter to the common (game-theoretic) wisdom that players in all of these games should employ greater depths of reasoning over time. in table  (b) we disaggregate some of the findings reported in table  (a) and note the frequency with which adjustment behaviour from one round to the next is consistent with the predictions of learning direction theory in each of our  sessions. using this session-level frequency data, we can test whether learning direction theory provides a plausible characterisation of our data. the null hypothesis is that the frequency of adjustment behaviour that is consistent with learning direction theory should, on average, equal ±. that is, in table  (b), for each transition period, we should observe roughly equal numbers of frequencies that are less than ± as we observe frequencies that are greater than ±. we use the binomial test to determine whether we can reject this null hypothesis for each of the three round-to-round transitions using the  session- level observations reported in table  (b).* we find that we can reject the null hypothesis for each of the three round-to-round transitions at a significance level that is always less than  %. we conclude that learning direction theory is a plausible way of characterising transition behaviour over the first four rounds of all three treatments. * see siegel and castellan (, pp. –) for a description of the binomial test used here. # royal economic society   table  classification of beha�iour according to learning direction theor� (a) used pooled data on rounds – adjustment ratio is rounds – rounds – rounds – " # -median game guess was " " # ref. pt. decreased ± ± ± increased ± ± ± ! " # ref. pt. increased ± ± ± decreased ± ± ± consistent with l.d.t.* ± ± ± " # -mean game guess was " " # ref. pt. decreased ± ± ± increased ± ± ± ! " # ref. pt. increased ± ± ± decreased ± ± ± consistent with l.d.t. ± ± ± " # -maximum game guess was " " # ref. pt. decreased ± ± ± increased ± ± ± ! " # ref. pt. increased ± ± ± decreased ± ± ± consistent with l.d.t. ± ± ± (b) the frequency with which adjustment behaviour is consistent with the prediction of learning direction theory over rounds – of each session rounds – rounds – rounds – " # -median game session  ± ± ± session  ± ± ± session  ± ± ± session  ± ± ± " # -mean game session  ± ± ± session  ± ± ± session  ± ± ± session  ± ± ± " # -maximum game session  ± ± ± session  ± ± ± session  ± ± ± session  ± ± ± # royal economic society                    [         ]                   table  (cont.) (c) using data or rounds – from the single ten-round session of each treatment adjustment ratio is rounds – rounds – rounds – rounds – rounds – rounds – " # -median game guess was " " # ref. pt. decreased ± ± ± ± ± ± increased ± ± ± ± ± ± ! " # ref. pt. increased ± ± ± ± ± ± decreased ± ± ± ± ± ± consistent with l.d.t. ± ± ± ± ± ± " # -mean game guess was " " # ref. pt. decreased ± ± ± ± ± ± increased ± ± ± ± ± ± ! " # ref. pt. increased ± ± ± ± ± ± decreased ± ± ± ± ± ± consistent with l.d.t. ± ± ± ± ± ± " # -maximum game guess was " " # ref. pt. decreased ± ± ± ± ± ± increased ± ± ± ± ± ± ! " # ref. pt. increased ± ± ± ± ± ± decreased ± ± ± ± ± ± consistent with l.d.t. ± ± ± ± ± ± * sum of the frequency numbers in boldface type which are consistent with the predictions of learning direction theory. table  (c) repeats the analysis of table  (a) but for the remaining six round- to-round transitions in each of the ten-round sessions for each treatment. we see that when the number of rounds played is increased beyond four, learning direction theory may fail to predict the transition behaviour of the majority of subjects. indeed, in the maximum game, an average of only ± % of adjustment behaviour over the last six rounds is consistent with the theory. however, in the median game, the behaviour of the majority of subjects remains consistent with the predictions of the theory in all but one transition period while in the mean game, the behaviour of the majority of subjects is consistent with the theory in all but two transition periods."! these differences may be explained by the theory’s assumption that subjects form their next round guesses conditional only on the outcome (the winning number) of the previous round. when the winning number of the previous round appears to be following a clear trend, then it is perhaps reasonable for subjects to condition their next round guesses solely upon the winning number of the previous round. this appears to be the case in the ten-round median game where extreme ‘ outlier ’ guesses have little influence, and consequently, the median guess and the winning number are monotonically decreasing over time. however, when the winning number of the previous round occasionally deviates from an established trend due to one or a few extreme guesses as in the "! a statistical test of whether learning direction theory is a good predictor of transition behaviour in the longer ten-round games would require that we have more than a single observation for each treatment. # royal economic society   ten-round version of the mean game, or when the winning number does not appear to follow any discernible trend, as in the ten-round session of the maximum game (see fig. ), then it may be less reasonable for subjects to form guesses that are conditional only on the winning number of the previous round. thus, predictions such as those of learning direction theory that are based solely on the outcome of the previous round may continue to perform relatively well in those circumstances where aggregate behaviour adheres to a certain established trend, but may perform poorly otherwise.""  .            we have examined the robustness of behaviour across three different experimental treatments of the ‘ beauty contest ’ game. all three versions of the game have the same equilibrium prediction, namely that all players announce zero. therefore, the differences in behaviour that we observe across the three treatments must be due to the various ways in which the problem is framed. we have suggested how the different ways of framing the ‘ beauty contest ’ game may lead to more or less coordination by groups of experimental subjects, or alternatively, how these different environments may encourage behaviour that is relatively more ‘ fundamental ’ or more ‘ speculative ’ in nature. we find that behaviour in the mean and median games is similar with respect to first round choices, depth of reasoning and the direction of learning. however, we also find evidence suggesting that the percentage change in guesses over rounds – is significantly larger in the direction of zero in the median game than in the mean game. furthermore, we observe that in the final rounds of the longer, ten-round median game session, subjects appear to be increasing their depths of reasoning whereas the same cannot be said for the mean game. we conclude that there is support for our hypothesis that guesses in the median game will be closer to the nash equilibrium prediction as compared with guesses in the mean game. we find even stronger support for our hypothesis regarding behaviour in the maximum game. first round choices in the maximum game are significantly higher than in either the mean or median games. furthermore, percentage changes in guesses over rounds – are significantly smaller in the direction of zero in the maximum game as compared with either the mean or median games. data from the ten-round sessions suggest that these differences between the maximum game and the mean and median games persist beyond the fourth round."# "" this explanation might well account for ho et al.’s () rejection of learning direction theory in their ten-round versions of the mean game using small group sizes. "# the relatively slower rate of convergence in the maximum game and our explanation for this finding may also account for ho et al.’s () finding that convergence to equilibrium in the mean game is slower with smaller group sizes of three players as compared with larger group sizes of seven players. in the smaller group size of three players, each individual player has a relatively greater influence on the value of the winning number. in this respect, the smaller group size treatment is most similar to our maximum game environment, where a single player determines the value of the winning number. # royal economic society                    [         ]                   when we examine the direction of learning we find that the behaviour of the majority of subjects is consistent with the predictions of learning direction theory over the first four rounds of all three treatments and we are able to reject the null hypothesis that the predictions of learning direction theory are not useful in characterising adjustment behaviour in these early rounds. however, we find that learning direction theory frequently fails to predict the majority of subjects’ actions in the later rounds of the maximum game, and is also somewhat less accurate in predicting behaviour in the mean game. this failure of learning direction theory in the later rounds of these games is likely due to the theory’s use of the previous period’s winning number as the reference point. despite the limitations of learning direction theory, we believe that this theory serves as an important building block for more complex models of learning behaviour. it may be especially useful for characterising behaviour in the initial stages of games such as the ‘ beauty contest ’ game when players have little experience with the environment. uni�ersit� of pittsburgh uni�ersitat pompeu fabra date of receipt of final t�pescript : februar� �� r camerer, c. and ho, t. h. 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(). ‘ strategic uncertainty, equilibrium selection principles, and coordination failure in average opinion games. ’ quarterl� journal of economics, vol. , pp. –. # royal economic society  _ _ _ _ -web .. r e v i e w numeric expression of aesthetics and beauty b. s. atiyeh Æ s. n. hayek published online: december � springer science+business media, llc abstract debate over what constitutes beauty, particu- larly beauty of the human body, has raged since philosophy began. interested scholars have debated the meaning of beauty for centuries. however, it seems that numbers and the resulting numeric relationships play a fundamental role in the classification of the human body, and that a harmonic profile or body shape is produced only at certain definite numeric relationships. the beauty of individual features depends on ‘‘ideal’’ proportions, and it is suggested that expressing beauty in terms of geometry is possible. as the demand for aesthetic surgery has increased tremendously over the past few decades, it is becoming essential to be able to assess the possible satisfaction that can be expected after an aesthetic surgery procedure and to determine the beauty of the final result as precisely as possible. keywords aesthetics � beauty � harmonic profile � ideal proportions � numeric expression because of the tremendous increase in demand for all types of both facial and body contour aesthetic procedures, an understanding of beauty is becoming of utmost importance in various settings of medical practice [ ]. a satisfactory cosmetic result and optimal healing is the aim of aesthetic surgery. it is essential therefore to be able to assess the possible satisfaction that can be expected after an aesthetic surgery procedure and to determine the beauty of the final result as precisely as possible [ ]. interested scholars have debated the meaning of beauty for centuries [ ]. in contemporary society, the media are largely responsible for providing universal yardsticks against which individual faces and body shapes are mea- sured [ ]. it appears that youth and symmetry are the most highly prized attributes of beauty [ ]. although experi- ments with holistic or individual feature representations of the human body have demonstrated the importance of features in discriminative tasks, studies suggest that humans perceive faces and body shapes holistically and not as individual features [ , ]. the beauty of individual fea- tures depends on ‘‘ideal’’ proportions [ ]. it seems that numbers and the resulting numeric relation- ships play a fundamental role in the classification of the human body, and that a harmonic profile or body shape is produced only at certain definite numeric relationships [ ]. it is sug- gested that expressing beauty in terms of geometry is possible [ ]. the resulting canons and constructive ideals of beauty provide definite aids and guidelines in plastic surgery [ ]. to date, the most favored preferences have been for the ratios of unity ( : ) and the golden section ( . : ) [ , ]. perhaps pythagoras was right after all in maintaining that mathematics underlies all and serves as the very basis of beauty [ ]. plato’s timaeus even claimed that within the properties of numbers themselves, the essence of the uni- verse could be found, and aesthetics is seen as a branch of this numeric cosmology [ ]. historical background although beautiful individuals make up a small percentage of the population [ ], beautiful and harmonious human b. s. atiyeh (&) plastic and reconstructive surgery, american university of beirut medical center, beirut, lebanon e-mail: aata@terra.net.lb s. n. hayek plastic and reconstructive surgery, university of minnesota, minneapolis, mn, usa aesth plast surg ( ) : – doi . /s - - -x figures have been present in artistic representations since antiquity. body measurements were used by the old egyptians to execute their famous sculptures and paintings. facial measurements were first performed by the greeks as part of total body measurements for the same purpose [ ]. rules defining the relationships between various face and body features were more clearly formulated by scholars and artists of the renaissance based on classical greek canons [ ]. more recently, the reasons for these measurements have not always been the same. some investigators have applied such measurements to create the art of ultimate beauty, whereas others have used measurements of human beings to imply that certain groups of people are superior [ ]. in modern medicine, the use of neoclassical formulas of human harmonious proportions was propagated by the artist-anatomists of the th to the th centuries [ ]. the secret of beauty debate over what constitutes beauty, particularly beauty of the human body, has raged since philosophy began [ ]. what is beauty and why are some humans considered more beautiful than others? [ ]. has the construct of beauty changed over time? is our sense of beauty learned or innate? what is beauty, and can we quantify it? [ ]. beauty is a universal phenomenon, present across many species and all ages, [ ] that heightens and clarifies our relationship to the world [ ]. it is a universal part of human experience provoking pleasure, riveting attention, and impelling actions that help ensure survival of our genes [ ]. as the formal aspect of idealization, it can embody the finest and most transcendent values in the human aesthetic experience [ , ]. from the renaissance artists to the present day, the quantitative definition of human beauty has been a ‘‘holy grail’’ [ ], and since antiquity, scholars and scientists have investigated the roots and effects of beauty, defining it in many different ways [ , , ]. according to a modern definition, beauty is ‘‘excelling in grace or form, charm or colouring, qualities which delight the eye and call forth that admiration of the human face in figure or other objects’’ [ ]. nevertheless, beauty is a mystery that has been with us for ages, and its presence is ubiquitous [ , ]. it is something we can recognize in an instant, yet it still is difficult to formulate [ ]. beauty is essentially a visual phenomenon and therefore is exposed to the influences of optical illusions [ ]. to be perceived as beautiful, structures need to be visually appealing and capable of evoking an emotional level of pleasure [ ]. the visual processing of human faces, the most complex and captivating structure in nature, whose attractiveness influences much of our behavior and social interaction, has attracted the imagination and received the attention of philosophers and scientists such as aristotle and darwin for centuries. the face has received most of the attention and generated most of the studies related to beauty and attractiveness [ , , ]. concepts and rules derived from these studies, however, may be applicable to all parts of the human body. the notion that beauty is in the eye of the beholder, and that individual attraction is not predictable beyond our knowledge of a person’s particular culture, historical era, or personal history has been widely held for centuries. however, more recent work suggests that beauty is not an inexplicable quality that lies only in the eye of the beholder and that the constituents of beauty are neither arbitrary nor strictly culture bound [ ]. beauty is a perception of the physical form appreciated by the observer. such a concept suggests that it comprises two distinct but competing ele- ments—the one who is beautiful and the other who considers the one beautiful—the ‘‘subject versus beholder hypothesis’’ [ ]. despite an apparent impression that every human society has its own standards [ ] and despite the fact that when culturally isolated populations are taken into account, some supposedly invariant standards may prove malleable [ ], cultural invariance combined with an adaptive potential has been used to support an adapta- tionist explanation of human beauty and to set culturally invariant standards of beauty [ ]. it seems that there is a universal standard for beauty regardless of race, age, sex, and other variables [ , ]. there is, however, evidence that certain perceptions of beauty change with time [ ] and that the recent globalization of modern society has wrought changes in our perceptions of beauty [ ]. most cultures to date have been exposed to the potentially confounding influence of the western media. many of the remotest places on earth have access to television, cin- ema, and advertising posters displaying exceptionally ‘‘wasp-waisted’’ gynoid females draped over desirable products such as cars and beer [ ]. beauty and attractiveness as mentioned earlier, the face has received most of the attention, and mankind’s interest in facial attractiveness and its study date back to the beginnings of recorded his- tory. determining the essence of this quality and its nature has occupied us individually and collectively at least from the time of the egyptians , years ago [ , , ]. attractiveness is an essential attribute of beauty, and bio- logically, beauty is something that the visual processing segment of the nervous system finds attractive [ , ]. these biologic phenomena are operative during early aesth plast surg ( ) : – adulthood [ ]. but what makes a female or male figure attractive? the observation of true beauty arouses an emotional level of pleasure perceived not in the neocortex, but deep within the subconscious limbic system [ , ]. such an arrangement has developed in response to the pressures that have shaped the brain throughout its evolution [ , ]. findings indicate also that brain activations during aes- thetic judgment cannot be reduced to an assessment of symmetry, but actually are due to a particular mode of judgment relying on a network that overlaps partially with underlying evaluative judgments made on social, religious, or moral cues [ ]. more precisely, aesthetic judgments can be considered a subset of evaluative judgments that, in contrast to descriptive ones, are reported to engage frontomedian areas around brodmann areas (ba) and , mostly together with the posterior cingulate cortex or precuneus as well as the ventral prefrontal cortex around ba / [ – ]. moreover, both aesthetic and symmetry judgments rely on a set of areas supporting high-level visual analysis [ ]. interestingly, ganglion cells in the retina are arranged so as to increase the dark–light boundary, making the visual cortex particularly sensitive to contrast, which is perceived as an attractive stimulus [ ]. we commonly think that attractiveness is based on subjective impressions largely affected by cultural stan- dards [ ]. this may not be correct [ ]. several rating studies have demonstrated high cross-cultural agreement in attractiveness rating of faces representing different eth- nicities [ , – ]. faces judged to be very attractive in one society are judged to be equally attractive in other societies [ ]. moreover, research findings from the field of psy- chology not only show that judges strongly agree about facial attractiveness but also indicate that a universal standard of facial attractiveness does in fact likely exist [ , ]. likewise, in evaluating human body attractive- ness, despite some cross-cultural differences, it also was shown, for example, that waist-to-chest ratio, body mass index (bmi), and waist-to-hip ratio are the major cues to women’s ratings of men’s bodily attractiveness regardless of the cultural setting [ , , ]. more recent studies have shown that the attractiveness of a woman’s figure can be predicted exactly from her body measurements. important predictors in that regard are bust- to-underbust ratio, bust-to-waist ratio, bust-to-hip ratio, waist-to-leg ratio, and an androgyny index (an indicator of a typically female body) [ ]. if different people can agree on which faces and body shapes are attractive and which are not when judging individuals of varying ethnic back- ground, this suggests that people everywhere are using similar criteria in their judgments [ ]. this high congru- ence over ethnicity, social class, age, and sex has led to the belief that perception of attractiveness is data driven and does not depend on any single feature [ ], and that the properties of a particular set of features are the same irre- spective of the perceiver [ ]. it also seems that judgment of attractiveness is an instinctive phenomenon suggesting an innate ability to appreciate beautiful form and balance irrespective of ethnic origin [ , , , ]. nevertheless, the general body of facial attractiveness research has shown that subjective attractiveness represents only a thin layer of personal preferences overlaid on a much larger and inevitable bio- logic objective assessment of attractiveness [ ]. from an evolutionary standpoint, function always precedes form [ , ], and evolutionary psychologists have argued for the existence of universally shared criteria of attractiveness, which are potent cues to a person’s potential reproductive success [ , ]. a substantial amount of work supports a darwinian theory of selection, which predicts a survival advantage based on physical attractiveness [ ]. this has been an issue since the dawn of sexual reproduction [ ]. if the genetic objective of life is to mate with the best available partner, any features promoting the owner’s genome will therefore be a favorable investment [ ]. throughout the higher animal kingdom, reproductive division of labor between the sexes has led to greater success through role specialization. beauty is a conse- quence of this process, exploited to demonstrate fecundity and attract a suitable partner [ ]. theory suggests that sexually reproducing organisms choose mates displaying characteristics indicative of high genotypic or phenotypic quality. attraction to beautiful individuals may therefore be an adaptation for choosing high-quality mates [ ]. although evolutionary biology holds that in any given population, extreme characteristics tend to fall away in favor of average ones [ ], natural variation within a species creates a range of phenotypes and thus a rank of survival advantage, ‘‘survival of the prettiest,’’ with some better adapted to attract a partner than others [ ]. a reliable connection exists, for example, between male body attractiveness and male fitness and qualities such as health and vigor [ , ]. like- wise, woman’s sexual attractiveness might be based on the ratio between her waist and hip measurements, a reliable index of her reproductive potential [ ]. an interesting finding, however, is a biologic trend away from perfect symmetry in primates consequent to adaptive evolutionary alteration favoring functional asymmetry [ ]. studies have demonstrated that the right hemisphere is dominant for visual recognition and identification, whereas the left hemisphere is associated with the per- ception and production of language. however, the degree of labor divisions differs between the sexes. men are more functionally lateralized for visuospacial skills and women for language [ , ]. moreover, beauty is shown to be more aesth plast surg ( ) : – pronounced on the right side of women faces (men show no difference), with lateralizing of facial expressions on the left. this lateralization is perceived by the left hemisphere of the observer, allowing beauty to be emphasized on the right side of the face and perceived by a male’s right (preferred) hemisphere [ , ]. the finding that no such mechanism for characterizing beauty is present in females confirms that beauty is a male-driven emotion based in evolutionary neuropsychology rather than a purely social concept [ ]. this by no means implies that females cannot experience beauty [ ]. canons of beauty: ideal proportions and harmonious features a common anthropometric element of all times is that man has tried to catch physical proportions into values [ ]. despite the claim that the egyptian artists did not use a line system to measure parts of the human body in relation to others, the principles for the canons of the human body may have been defined by them [ ]. some studies have demonstrated that egyptian artists divided the available space for representation of human body figures from top to bottom into . like parts. it is suggested also that the egyptians took the middle finger to be / of the adult man’s length. however, well-defined landmarks such as the nipples, umbilicus, and knees were not localized along these divisions [ ]. the greeks and romans were heavily influenced by the egyptians [ ]. aristotle ( – b.c.) emphasized the proportions of aesthetics and described the science of reading one’s character from one’s bodily features [ , ]. polycleitus ( – bc), a greek sculptor obsessed with the beauty of male athletic bodies, seems to have been the first to define canons, probably based on egyptian princi- ples [ , ]. he reported the height of the face to be / the length of the body and the whole head to be / of it. the head and neck together were to be / of the athlete’s length [ ]. these proportions were expressed in his famous statue of doryphorous [ , ]. only a few centuries ago, human features and canons were not realistically acknowledged [ ]. it was during the renaissance period that the classical, originally greek canons of proportion were formulated and documented by scholars and artists such as durer, alberti, cousin, audran, francesca, pacioli, cennini, savonarla, and da vinci, among others [ , ], leading to the development of neo- classical canons defining primarily the interrelationships of facial structures [ ]. because of propagation by the artist- anatomists of the th to th centuries, these neoclassical canons later continued their popularity in the field of medicine [ , ]. leonardo da vinci ( – ) probably was the first to report extensively on the proportions according to which bodies and faces should ideally be shaped, and he applied these canons in his art [ ]. according to da vinci, in a well-proportioned face, the size of the mouth equals the distance between the parting of the lips and the edge of the chin, whereas the distance from chin to nostrils, from nostrils to eyebrows, and from eyebrows to hairline all are equal, and the height of the ear equals the length of the nose [ , ]. albrecht durer ( – ) also felt that a system of canons could be devised that would define the ideal proportions for human figures and heads [ , ]. he divided the face into three equal lengths: the forehead, the nose, and the mouth and chin [ ]. although da vinci dictated strict canons for facial and bodily proportions, he could not deny the natural variations of nature [ ]. neoclassical canons still are used widely in art, sculp- ture, and painting. they often have been used by modern plastic surgeons as working guides. studies have been conducted recently on the validity of these canons in real populations, in caucasians [ , , , ], in african americans [ , ] and in asians [ , ]. these studies have shown that ‘‘while some of the neoclassical canons may fit a few cases, they do not represent the average facial proportions’’ [ , , ]. as a matter of fact, measurements deduced from classic works of art and science depict the subjects in the way the artist or scientist preferred them rather than how they really were [ ]. the neoclassical canons, although a reliable rough working guide to facial proportions for artists and sur- geons, are clearly not a valid system for analyzing the real human face [ , ]. even in art, the influence of these canons had diminished by the late th century [ ]. compared with the wide range of natural proportions, the neoclassical canons represent rigid, simplistic rules. they cannot be accepted as the sole representatives of aesthetic features [ ]. more recently, other objective systems have been pro- posed, including the anthropometric and cephalometric systems [ ]. physical anthropology has its roots in the th and th centuries, when most of the facial mea- surements were taken directly from skulls, and only a few soft tissue measurements were performed [ ]. unfortu- nately, many used facial and skull measurements during this period to show that blacks and others were inferior to whites [ , ]. cephalometric measurements, an indirect form of craniometry (measurements from dry skulls) and facial anthropometry (measurements from live heads and faces), were introduced by broadbent in [ ], and during the first decades of the th century, pioneering orthodontists initiated cephalometric radiology: the quan- titative determination of structural changes in radiograms of the facial skeleton [ ]. aesth plast surg ( ) : – the father of modern rhinoplasty, jacques joseph ( – ), presented what he considered to be the ideal nasal shape with a combined length of the three parts of the nose (the bony part, the septal cartilaginous part, and the cartilaginous and soft tissue tip) equal to the length between the base of the nose and the edge of the chin [ ]. mario gonzalez ulloa ( – ) introduced the concept of profileplasty, positing that the glabella, subnasal point, and pogonion should ideally be in line, and that this imaginary line should be perpendicular to the frankfurt horizontal [ , , ]. the system that began as a simple dental analysis has since developed into a more complex lateral facial skeletal analysis, sometimes enhanced by soft tissue parameters [ ]. recently, farkas [ , , ], the modern father of soft tissue facial anthropometry, has most importantly influenced modern facial soft tissue anthro- pometry and revised the neoclassical canons correlating these canons to current norms [ ]. golden number u (phi) in the s, the golden ratio (golden number, golden proportion), an irrational number represented by the sym- bol u (phi = . ...), in reference to the greek sculptor phidias, made a reappearance and currently is used as a valid ratio between various facial and body features [ , ]. the ancient egyptians applied the golden propor- tion in their architecture. although they did not explicitly describe it, we assume that they had already been aware of its aesthetic attractiveness [ , , ]. it was first recorded in the third century bc by the pythagoreans and later by the greek geometrician euclid [ ]. the golden number is a ratio obtained when a line abc is sectioned such that ab/ac = bc/ab [ , ] (fig. ). it also can be derived easily from the fibonacci sequence, in which each number is the sum of the two preceding numbers ( , , , , , , , , , , , , , ...) [ ]. sur- prisingly, the reciprocal of u is . ... (u – ) [ ]. the golden number is the only number that yields its own reciprocal when subtracted by units [ ]. phi (u) could be the world’s most astonishing number [ ]. for centuries, scholars have believed that the golden section results in the most pleasing ratio considered to be the cornerstone and the key to the secret of beauty [ , , ]. it still is believed by some investigators to underlie the aesthetics of an ideal face and body shape and to be the standard for balance and beauty [ , ]. because it is related to so many aspects of beauty, u later was called the divine number or proportion [ , ]. the golden number appears almost ubiquitously in nature and is found in numerous natural phenomena and geometric propositions; in art, music, and human architectural constructions [ , , , – ] including the basic geometric shapes of the pentagon, decagon, and dodecagon; in the phyllotaxis or leaf arrangement of a vast number of plants and flowers; in the spiral of seashells such as the nautilus; in the human mandible and its growth rate; and even in the spiral of dna [ , ]. it represents some remarkable relationships between aesthetically pleasing proportions of patterns exhibited by living plants and animals [ ]. this golden proportion has been defined as the ratio most attractive to the human eye and mind [ ]. the human figure and face share mathematically pro- portioned relationships similar to those of other living organisms [ , ]. beautiful faces, for example, have ideal facial proportions directly related to the divine proportion [ ]. ricketts [ ] found the width of the mouth to be u times the nasal width. when the width of the mouth is , the distance between the outer corners of the eyes is u. the width of the head at the temples, again, is u times the distance between the outer corners of the eyes. vertically, the height of the forehead from hairline to eye pupils is , where the height of the face from pupils to chin is u. a golden proportion may be found also when the height of the face from pupils to chin is divided into the distance between the pupils and the nasal alae on the one hand and the distance between the nasal alae and the chin on the other. if the distance between chin and mouth is , the distance between the mouth and the pupils, once more, is u [ ]. likewise, in the hand, the proportion of each phalanx to the adjacent one in every finger is in total conformity with the golden proportion [ , ]. after a proportional analysis of the human body, the swiss-born, french-trained revolutionary architect and artist, charles le corbusier, concluded that the most beautiful, harmoniously proportioned human bodies (or sculptural representations of them) contain many divine proportions [ ]. perhaps the most famous illustration relating divine proportion to human anatomy is leonardo da vinci’s drawing of the ‘‘human figure in a circle,’’ illustrating the proportions recorded by the roman author vitruvius [ , , ]. empirical investigations of the aesthetic properties and primacy of the golden section were among the very first topics of scientific psychological research as the new dis- cipline emerged in the th century and date back to the fig. the golden section u and its reciprocal. a line ac is divided in two segments ab and bc so that the ratio of the full line over the long segment ab is equal to the ratio of the long segment ab over the short segment bc aesth plast surg ( ) : – very origins of scientific psychology itself. the very first studies were conducted by fechner in the s [ , ]. since that time, it has been the focus for a number of research programs, winning the attention of structuralists, gestaltists, behaviorists, social psychologists, psychiatrists, and neuroscientists at various times [ ]. adolf zeising probably is the most significant figure in the th century for the revived interest in u [ ]. ghyka [ ] and seghers et al. [ ] were the first to introduce the golden proportion into the modern medical literature. however, it was ricketts [ , – ] who popularized the concept in facial surgery. it seems that through an evolutionary process, nature has created the standard of aesthetics based on the divine proportion [ ]. all living organisms, including humans, are genetically encoded to develop to this proportion, perhaps because of extreme aesthetic and physiologic benefits [ ]. all human beings should have the genetic potential to attain these proportions. it is proposed that such a human form upholds the law of conservation of energy, allowing maximum performance with minimum effort, and the law of conservation of tissue, requiring the minimum number of cells to perform the tasks necessary for survival. an individual may, however, fall short of achieving this form due to race, age, or sex, or because of geographic, cultural, or environmental (mainly malnutri- tion) factors [ , , ]. it also seems that appreciation of this proportion is primitive and inborn. living organisms are biologically attracted to potential mates who conform to this strict proportion [ ]. a recent mathematical modeling system has been developed for human facial attractiveness by marquardt [ , ], who used the primary pentagonal complex to form the basic framework of a mask, applying specific lines, line segments, and points to construct the component lines and points of the mask [ ]. these pentagon complexes are in fact variously sized golden or regular decagons, which can be created by superimposing two same-sized golden or regular pentagons pointing in opposite directions [ ]. the marquardt mask is a facial overlay system variously called the phi, archetypal, golden, or golden ratio mask built entirely by using the ratio phi. it has been claimed adaptable to the creation of an objective system for mea- suring facial attractiveness [ , , ]. the phi mask method relies on the hypothesis that attractiveness is averageness, but there is controversy regarding the signif- icance of average and attractive [ ]. conclusion throughout history, studies have been conducted and still are ongoing about what constitutes the ‘‘perfect beauty,’’ a question that scientists still need to answer, artists need to show and create in their work, and physicians need to keep and improve [ ]. currently, beauty standards are not clear. however, they should be in accordance with artistic mode and style as well as the natural form and shape of the human figure. after all, beauty should confirm certain dimensions [ ]. various disciplines have studied the nature of beauty. individually, they provide partial answers, but when viewed together, they begin to weave provocative insights as to beauty’s biologic significance [ ]. physical appearance has been an inseparable part of daily human existence [ ]. the three elements that exert the greatest influence in human relationships are physical and sexual attractiveness as well as beauty. physical attractiveness alone influences success, power, happiness, and satisfaction in life [ ]. most individuals see them- selves as a reflection in a mirror and prefer to be labeled as beautiful [ ]. although researchers have found that there is a con- sensus on rating attractiveness across sexes and sexual orientations, ethnic groups, and ages from infants to the elderly [ ], historically, the aesthetic concept of beauty is not a fixed one. it changes often, and beauty standards also are modified according to many dimensions. these are influenced by social, material, and ethnic factors, in addi- tion to religious beliefs and customs [ , ]. the many faces of beauty through the centuries differ from one civilization to another. the roles, parameters, and dimensions of beauty also differ [ ]. unfortunately, there is no golden key to open every door for analysis of attractiveness among races [ ]. a fuller evolutionary theory of human beauty must embrace variation rather than focus on ‘‘universal’’ traits to the exclusion of cultural effects [ ]. of course, physical features are involved in mate choice, and natural selection probably has shaped these preferences [ ]. however, we obviously need a more sophisticated evolutionary analysis to explain variation in preferred body shapes and sizes that does not ignore the effects of environment on ontogeny [ ]. when considered in a historical perspective, some can- ons of beauty seem to be in agreement with each other [ ]. however, farkas [ , , ] found the proportions defined by the various described canons to be present only inci- dentally. the same applies to the golden proportion [ , ]. the golden section phenomenon may be unreliable and probably is artifactual [ ]. although it has been men- tioned that the ‘‘average’’ face may very well conform to the divine proportion [ ], only in the faces of a highly selected group of humans can such proportions be found [ , ]. however, there seems to be, in fact, real psycho- logical effects associated with the golden section [ ], and aesth plast surg ( ) : – studies suggest that its traditionally described aesthetic effects may well be real. however, if so, they are very thin indeed [ ]. whether the golden section per se is important, as opposed to similar ratios ( . , . , or even . ), is very unclear [ ]. nevertheless, irrespective of age, the golden proportion will help to identify unbalanced areas and guide in accomplishing harmony and beauty [ ]. something like an artistic vision of reality is needed to remind scientists that most natural phenomena are not described adequately if they are analyzed piece by piece. that a whole cannot be attained by the accretion of isolated parts is not something the artist had to be told [ ]. a recent study has shown that the attractiveness of a female figure is the result of complex interactions among numer- ous factors. therefore, in the planning of a surgical intervention, it is important not to focus on a 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canons of beauty: ideal proportions and harmonious features golden number &phgr; (phi) conclusion references << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (none) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /perceptual /detectblends true /colorconversionstrategy /srgb /dothumbnails true /embedallfonts true /embedjoboptions true /dscreportinglevel /syntheticboldness . /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize true /opm /parsedsccomments true /parsedsccommentsfordocinfo true /preservecopypage true /preserveepsinfo true /preservehalftoneinfo false /preserveopicomments false 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social and behavioral sciences ( ) – available online at www.sciencedirect.com - © the authors. published by elsevier ltd. this is an open access article under the cc by-nc-nd license (http://creativecommons.org/licenses/by-nc-nd/ . /). selection and peer-review under responsibility of the organizing committee of psysoc . doi: . /j.sbspro. . . sciencedirect psysoc swan as a symbol of beauty and purity in kazakh poetry nagbdu kamarova a * a caspian state university of technologies and engineering named after s. yesenov, micro district, aktau city , the republic of kazakhstan abstract the paper discusses the use of swan image in kazakh poetry. swan is one of the traditional images in kazakh poetry. the tradition of celebrating swan as a symbol of beauty, laid by asan kaigy in the th century has also found its extension in modern kazakh poetry. in the poems of s. seifullin, i. zhansugurov, k. amanzholov, m. makatayev, k. akhmetova, k. salykova the swan is praised as a symbol of purity, beauty and holiness. comparison of different writers and their examples of the images of a swan in the literature are provided. the poems of asan kaigy, k. amanzholov, s. seifullin are analyzed from the point of view of the image of swan description. © the authors. published by elsevier ltd. selection and peer-review under responsibility of the organizing committee of psysoc . keywords: swan symbol, kazakh poetry, traditional images . introduction having found its continuation in kazakh poetry the tradition of swan celebration as a symbol of beauty takes its origin in the creative work of asan kaigy. every national literature has its own peculiarities of understanding and nature perception. thus, in russian poetry among other acts of nature, the most often praised and specially given prominence is a tree. birch, snowball tree and fir tree are not just trees in russian poetry, but national poetic images. nomadic way of life of kazakh people is very close to nature. kazakh people have been wandering along the shores and rivers. the closest image is the image of the bird swan. in nomad’s perception swan is a sacred bird. swan is considered a beautiful bird, that is why girl’s beauty is compared as a rule with the beauty of swan and beloved person is called “my swan” (“my lebyodushka”). in fiction we can find such comparisons and steady word- combinations, as “kustai kirshik ak” (perfectly pure as swan), akku kustai zharkyldau (sparkle like swan), akkudai *corresponding author: nagbdu kamarova. tel.: + - - - e-mail address: nagbdu@mail.ru © the authors. published by elsevier ltd. this is an open access article under the cc by-nc-nd license (http://creativecommons.org/licenses/by-nc-nd/ . /). selection and peer-review under responsibility of the organizing committee of psysoc . http://crossmark.crossref.org/dialog/?doi= . /j.sbspro. . . &domain=pdf nagbdu kamarova / procedia - social and behavioral sciences ( ) – (like swan), akkudai sylanu (perk like swan), akku kustyn moinyndai (swan neck), aidynnyn erke sulu akkuyndai (water favourite is swan beauty), akkudyn mamygyndai (like swan feather), akkudai tizily (line up like a swan), etc. like the favourite of water – swan beauty golden moon floats silently in the sky. (k. amanzholov). pedigree racer is flawlessly pure like a swan, it is like being presented by a devoted friend. (s. seifullin). her white hands like a swan neck. (i. zhansugirov). swan is one of the traditional poetic images in kazakh poetry. saken has poetized swan many times. he mentions swan in the poem “sholde” (“in the desert”) for the first time. in this poem, written during the times of the author’s persecution, we can see writer’s grief about his native land, mother, his beautiful wife. if the first part of the poem is called “dombra” (national kazakh musical instrument), the second part was called by the poet “akkuga” that means “devoted to swan”. in this part the author communicates the feeling of grief that filled his heart. the image of swan expressed author’s hope for nearest release from ties, and hope for the nearest joy. through the image of swan that will help him to release and settle in his soul the hope for kindness triumph, he sends his love to his motherland. there is a tradition in poet’s poems to send love to the motherland with the help of the birds. but why the author has chosen swan, there are many other birds in the desert. using the image of swan the author tells not only grief about his motherland but also his delicate feelings to his beloved and dearest whom he left in the beautiful area of saryarka. saken praises the swan as a special image of love, friendship and beauty. we find out about his aspirations in life, in the poems to beauty and purity and everything beautiful through his poetic lines “tugannan sagan gashykpyn” (“i have been in love with you since i was born”) in his poem “akku kus” (“swan bird”). the swan flies like strong wind everything is singing merrily around and the lake has enveloped the swan enveloped slowly the chest. spreading like a mirror its white chest (s.seifullin, ). the author compares swan’s flight and tenderness of a beautiful girl’s movements. in this description swan symbolizes not just girl’s movements tenderness but he is the symbol of their freedom. in this poem the author compares the swan’s flight with “the power of wind”. if to evaluate this poem from the epoch point of view, when saken lived, swan has been the symbol of beauty, magnificence, tenderness. it is presented to us from another point of view. such feelings as beauty, magnificence of nature are an eternal category for the human. s.seifullin’s poem “akkudyn airyluy” (“swans’ parting”) has embodied in itself all these notions. this poem is a legend about great love with the only goal that has embodied confident aspiration into the future. there is a thought in it that passionate love, made oath, sincere friendship is better than unhappy life full of violence. poet’s personality as an artist is unified with the nation. it is the very poem that we can absorb folklore images and legends from. because of this poem is sincere, pure and correct image of native folklore. the image of a swan in s. seifullin’s poem is represented as a symbol of love. possessing this quality, swan’s image is preserved in our consciousness as a special symbol of beauty. the sacred bird is not just a symbol transferring sincere feelings of the lovers but also an artistic means of displaying honesty, sincerity which are the driving force of keeping balance and sincerity of human feelings in the world. saken treated swan image in his poetry love’s messenger. the main peculiarity of the poet’s creative work is that while creating swan’s image, the poet endows him with feelings which are peculiar of a human. speaking about love of winged beauty the poet touches upon the theme of human feelings and relationship. one of the poets understanding the whole power of human soul and paying attention to such valuable qualities of a person that not everybody could see was mukagali. he has left us an inheritance as a beautiful monument to the swan in poetry, supplementing and showing all the beauty of the nature, his poem “akkular uiyktaganda” (“when swans sleep”). this poem is to become the heritage that will be handed down from generation to generation. makatayev’s poem “akkular uiyktaganda” is a monument to beauty. the image of swan is presented manysidedly here. located on the top of the mountain, “like drops of rain on a stone”, transparent, small lake is weary of loneliness. this lake is called zhetimkol that means, “orphan lake”. today it seems that “there have not been what nagbdu kamarova / procedia - social and behavioral sciences ( ) – have been really before” – white wings swans, swimming on the surface of the lake. beautiful lake sorrows like blue eyes of a blue mountain skyrocketing where green fir trees grow. transparent lake sorrows about the swans that transform nature, without which even sparkling sun rays loose its beauty. charming nature, the beauty of which can be observed but it is not possible to describe its beauty with words. he cannot be happy on the one reason only – there is no chime of the swans’ wings flying up in the early morning. swan song is a poem song. thus, the author has a thought that bird songs is like a symbol of love, a true feeling that takes special place in the heart of a person and in nature without this song grief and depression hang over the earth. there is a national wisdom, that says: “akkusyz kol zhetim”(“lake is an orphan if there are no swans in it”). and lake zhetimkol having absorbed all this wisdom is an orphan. the man who feels that involuntary lapses into grief. real poet artist possesses a special gift to convey the variety of the beauty of the nature with the help of only a few words. mukagali could skillfully convey the beauty of the swan’s movements, efficiently using vivid expressions in his work. let us try to answer the following question: why do we consider a swan to be the symbol of beauty of the nature in the poetic world of mukagali. we have mentioned that lake is beautiful when there are some swans. how the poet praised the swan beauty in his works. the poet does not change the places that can show us all the beauty of the swans. both mukagali and saken made the lake the place of swans inhabitance. also the poet has chosen the time to show the swan’s beauty on the lake as early morning. in the next lines the author says that one of the wonders, bringing joy together with sunrise is swan: sun rays are thrown about on the high ranges, they have broken up along the lake. the bird is white, the mirror like surface is white, the lake is whiter than white, white ray has fallen into pieces. the lake with the sky and the sky merge with the lake, and beautiful swans deliberately wake up (makatayev, ). only the poet with an open soul can become the witness of harmony in nature and praise it in his poems. only when the bird, lake and sunrise rays cover the earth – all this becomes one unity. you must have noticed that sunrise rays do not spread but radiate light. like an innocent pure angel similar to baby’s laughter scattered about like beads is revealed to the world. the spirits rise because there is a harmony on the earth in such early morning. we admire the swan the image of which we know as sacred power, bringing light together with sunrise. how could poet makatayev manage to sublimate the swan image to the necessary level. there are no strange sounds for him in the nature, he hears all various sounds. for the poet who is capable of enlivening the scenery, lyrically show the beauty of the swan from the psychological point of view, this bird is not just a symbol of pure, tender love, it is also a close image to heart, which he worships. when your wings clapped jingly, my soul trembled. in your interrupted way i sacrificed my interrupted soul. disorderly drawn out on the smooth surface of the lake there are beauties who cannot leave you, the desert. why i was not born a swan, i cannot be a man (ahmetova, ). the poet is disappointed when he sees how swans die because of people, there is an inexpiable sorrow when he sees a flock of swans that leave their lakes and go to warm countries. the poet’s soul always strives for the best. mukagali who has the talent to speak even with falling leaves acknowledges the power of beauty in the swan's image, possessing the gift to give people joy, hope and forget little difficulties of fleet life. reading those lines we begin to understand the poet’s wish with tender soul in its nature during the moments of joy or in the state of disappointment and sorrow, fly as freely as swan and swinging its wings and setting up justice on the earth. from these lines we can see that the swan is the source of poet’s power during the minutes of his disappointment. life is valuable by the moments of joy and grief that rush the person like waves. describing not only the image but also sorrowful voice of the swan, its beautiful figure the poet dreams about an unspoiled world. apricots evolve the fragrance, sweet smelling flowers evolve the fragrance and i rush to you like a swan (ahmetova, ). kulyash ahmetova in its poetry describes the swan not just as a messenger of feelings, she wants to show it as nagbdu kamarova / procedia - social and behavioral sciences ( ) – the image of her careless youth. emit the triumph like a flower, appearing in a merciful season that has grown in the shadow how many holidays there are! the steppe is in blossom, when girls in red and green dresses come there. emit the beauty like a swan on the smooth surface of the lake, beauty makes the girls grown up too early (ahmetova, ). with years, looking back at her own youth, looking at it with a judging look she sees the image of a swan with a grief. being joyful every day, she compares the youth with the lake, pure like transparent blue sky, like a high mountain, like a master of the dream and the center of all the best. expressive means in the poetry in the lines of the poem come from not just a simple aspiration to be expressed beautifully but because of aesthetic perception of the feeling of the image, expressive thinking in the world perception as a poet artist. the poetic beginning giving the poem and every image, every word in a poetic piece of literature there is a deep feeling of consciousness and expressive thinking of a poet. to understand the peculiarities of the language of the poetry you should be capable of feeling the poet’s thoughts well and also peculiarities of his artistic thinking and peculiarities of world perception from aesthetic point of view. for some reason the word “poetry besides “poem” and “rhyme” has the meaning of “beauty”. the poetry is born of deep tender feeling. it means experience and heart beating. that is why kulyash ahmetova describes the image of the swan in her poetry, linking it with a definite moment in the person’s life. the image of the swan is shown in her poetry as the messenger of pure love in her youth. one of the poets who contributed a lot in depicting the peculiarities of the image of the wonder of the nature after mukagali is kakimbek salykov. though not so many works are devoted to this topic, all of them are very significant and weighty, their scope is wide like kazakhstan vast steppe and their aspiration is as high as the tops of kazakhstan mountains. there are many poems in salykov’s lyrics devoted to the feeling of mutual understanding. there is a reason here why the word “love” is substituted for “mutual understanding”. there are no such habitual words, as “i love”, “i burn out of love”, that we can find in the creative works of other poets. the author who treats the theme of love differently cannot go past the image of swan for more expressive rendering of his feeling to his beloved. and it is clear. though the author does not provide his reader with some knowledge on high aesthetic level in conveying the image of the sacred bird which is associated in the nation’s consciousness as a symbol of the beauty, still he has a lot to say. the relationship between nature and humanity compose the whole entity. the man’s outlook towards environment itself is formed in the connection with his environment. from this point of view the author has developed a very wise and strong thought. the poet deeply feeling the beauty with all his soul is very upset because the swan becomes a victim in nature. he starts speaking about the swan to express his feelings: the swan, a white tsarina, i will open my secret to you. i will sing your image in a song, like the image of a white-faced girl who is in love. you are a balmy of the heart, direct your wings to me. come close to me and comfort your friend hugging with your white broad wings (salykov, ). the author conveys his feelings to his beloved through the image of swan. humanity aspiration from its very beginning to beauty and the wish to envelop this beauty – all this resembles outside beauty of the swan and the beauty of his movements. salykov is characteristic of the fact that he searches for the beautiful image of the swan in young girls surrounding him. the poet does not limit himself just by the search of tender girls. he devoted to them his tender poems and allows them to understand that he would like to be near the same girls as a swan next to snow-white girls. the poet’s heart is overflown with joy when he sees how a swan opens his wings like a flower. the poet cannot withdraw his eyes from this beautiful picture: the swan did not leave me and listened to her mysteries. i suffered that my eyes were not enough, nagbdu kamarova / procedia - social and behavioral sciences ( ) – to find out this beauty (salykov, ). we can not help noticing that in salykov’s poems the swan is described through the image of a beautiful girl. this is no way connected with cosmogonic notions. it looks like that the poet has the aim to praise every day routine life in his poems, and appeals to his reader to search for his ideal not in the far alien places but near, next to himself. that is why the following his lines can be considered regular: the same sunrise will come, that will make me forget my torments. i would like just to see shortly the beauty of snow-white beauty. there is a tender song, there is an excited voice and this very she swan cannot leave my memory the one that i have not met yet (salykov, ). swan is a strong image in makatayev’s creative work. the poet has the aim to accentuate his attention not on the glaring natural beauty of the bird but on its sacred power. none of the poets could hit it over the fence of the readers in the artistic style, like mukagali did it that in the basis of the sacred bird there are such qualities that influence taboos preservation in the national understanding. the poet managed to fill the image of the swan with the thought that together with world’s balance loss, national essence also losses its value. the poet tries to protect the humanity from ignorance with special discernment because he has acquired the magic power of this quality overestimation. makatayev’s swan is a huge image that has absorbed all life philosophy. this image embodies not just a symbol of love of a separate person. it collects mercy in its pure form and all other best qualities of the humanity. saken renders the swan image with an artistic skill as a symbol of flawless beauty, eternal and pure love, the image transferring the tenderest feelings of the lovers, the image that is the basic driving force in the sincerity of human relationship. though poetess kulyash ahmetova praised the sacred bird with great joy and with all her soul, she could not turn the swan in the basis of her poems, but she manageв to render such ancient notion as “sacred” as a woman, mother and poetess. the peculiarity of this poetess creative work is that she shows herself in the image of tender and helpless swan. at the same time the poetess does not go deep into life philosophic recollections while swan describing, still she manages to show tender features and qualities of a woman. our great famous poets managed to embed into the image of swan original and special recollections about the world surrounding us. the poetess managed to show the peculiarities of the perception of tender, sensitive nature by the person with the same tender and sensitive soul. whatever thoughts she has expressed in connection with the bird swan, she goes deep into her soul more than praises other people’s feelings. kakimbek salykov’s poetry also has a prevailing tradition to praise his own experiences. the poet does not describe passionate, fervent feelings but at the same time he tries to embed into the image of swan the notion of beauty and love. however, swan image celebration in the poet’s creative work does not make us happy with its peculiarity or novelty. it is necessary to point out only the realistic thought of the poet about the fact that we should search for the symbol of pure love not in the heaven but on the earth. conclusion: in our poetry different poets, variously using their creative potential with peculiar features have described the swan’s image. due to that this image was many sidedly exposed. the image of a sacred bird embodied all the best earth qualities, such as love, beauty, purity, perfection, faithfulness, peace, harmony and many others and turned into a high artistic image. references: seifullin s.( ). swan parting. rhymes and poems. almaty: atamura. p. makatayev m. ( ). amanat. almaty: atamura. p. makatayev m. ( ). the heart sings. (pp. - ). almaty: zhasushy. pp. - . akhmetova k. ( ). a leaf is the heart of summer. almaty: zhasushy. p. . salykov k. ( ). autumn tune. astana: yelorda. p. salykov k. ( ). a mature swan. almaty: kainar. p. the beauty contest and short-term trading∗ giovanni cespa† and xavier vives‡ november abstract short-termism need not breed informational price inefficiency even when gen- erating beauty contests. we demonstrate this claim in a two-period market with persistent liquidity trading and risk-averse, privately informed, short-term investors and find that prices reflect average expectations about fundamentals and liquidity trading. informed investors engage in “retrospective” learning to reassess inferences (about fundamentals) made during the trading game’s early stages. this behavior introduces strategic complementarities in the use of information and can yield two stable equilibria that can be ranked in terms of liquidity, volatility, and informa- tional efficiency. we derive implications that explain market anomalies as well as empirical regularities. keywords: price speculation, multiple equilibria, average expectations, public informa- tion, momentum and reversal jel classification numbers: g , g , g ∗a previous version of this paper was circulated under the title “expectations, liquidity, and short- term trading”. for helpful comments we thank elias albagli, max bruche, giacinta cestone, hans degryse, marcelo fernandes, itay goldstein, peter hoffmann, harrison hong, peter kondor, jean- paul laurent, olivier loisel, stephen morris, richard payne, ioanid roşu, kristien smedts, gunther wuyts, lian yang, kathy yuan, and participants at numerous seminars and conferences. cespa acknowl- edges financial support from esrc (grant no. es/j x/ ). vives acknowledges financial support from the european research council under the advanced grant project information and competition (no. ) and from project eco - of the spanish ministry of science and innovation at the public-private sector research center at iese. †cass business school, city university london, and cepr. , bunhill row, london ec y tz, uk. e-mail: giovanni.cespa@gmail.com ‡iese business school, avinguda pearson, , barcelona, spain. it might have been supposed that competition between expert profession- als [. . . ] would correct the vagaries of the ignorant individual left to himself. it happens, however, that the energies and skill of the professional investor and speculator are mainly occupied otherwise. for most of these persons are [. . . ] largely concerned, not with making superior long-term forecasts [. . . ] but with foreseeing changes in the conventional basis of valuation a short time ahead of the general public. (keynes, the general theory of employment, interest and money, ) does short-termism breed informational price inefficiency? we find that this need not be the case—even though beauty contests arise—provided that liquidity shocks are per- sistent. we examine this question in a two-period market where short-term, informed, competitive, risk-averse agents trade on private information and to accommodate liquid- ity supply while facing persistent demand from liquidity traders. traders’ “myopia” ranks high on the regulatory agenda, which testifies to policy mak- ers’ concern about the possibly detrimental effects of such myopia on the market. debate over this issue has a long tradition in economic analysis. indeed, short-term trading is the very basis of keynes’s dismal view of financial markets. according to his “beauty contest” analysis, traders’ investment decisions are driven by anticipation of their peers’ changing whims and not by actual knowledge of the companies they trade. as a result, competition among informed traders does not necessarily counteract the actions of unin- formed traders. it has been claimed that this type of behavior introduces a particular form of informational inefficiency whereby traders tend to put a disproportionately high weight on public information in their forecast of asset prices (see allen, morris, and shin while the market presence of traditionally long-term investors such as institutions has steadily increased during the last two decades, their holding period has decreased substantially (see oecd, http: //www.oecd.org/daf/fin/financial-markets/ .pdf). haldane and davies ( ) examine a large panel of uk- and us-listed companies over the period from to ; they find compelling evidence of investors’ short-term bias, which is even more pronounced in the last years of their sample. “or, to change the metaphor slightly, professional investment may be likened to those newspaper competitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average pref- erences of the competitors as a whole; so that each competitor has to pick, not those faces which he himself finds prettiest, but those which he thinks likeliest to catch the fancy of the other competitors, all of whom are looking at the problem from the same point of view. it is not a case of choosing those which, to the best of one’s judgment, are really the prettiest, nor even those which average opinion genuinely thinks the prettiest. we have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. and there are some, i believe, who practise the fourth, fifth and higher degrees.” (keynes, the general theory of employment, interest and money, ). http://www.oecd.org/daf/fin/financial-markets/ .pdf http://www.oecd.org/daf/fin/financial-markets/ .pdf ( )). furthermore, the anticipation of short-term price movements may induce mar- ket participants to act in a way that amplifies such movements (shin ( )) and may contribute to crashes. we show that the beauty contest analogy for financial markets tells just part of the story because, when liquidity traders’ demand shocks are persistent, prices reflect average expectations not only of the fundamental value but also of liquidity trading. in this paper we present a two-period model of short-term trading with asymmetric information—in the tradition of dynamic noisy rational expectations models (see, e.g., singleton ( ), brown and jennings ( )). we find that if liquidity trading is per- sistent then there is strategic complementarity in the use of private information, and we provide sufficient conditions for that complementarity to generate multiple extremal stable equilibria that can be ranked in terms of price informativeness, liquidity, and volatility. in particular, we find that there are two extremal equilibria: a “high informa- tion” equilibrium (hie) and a “low information” equilibrium (lie). at the hie, prices are good signals of the underlying fundamentals, volatility is low, and liquidity is high; the lie displays the opposite properties in terms of informational efficiency, volatility, and liquidity. in a model identical to ours but with transient liquidity trading, allen, morris, and shin ( ) find that prices (i) are driven by higher-order expectations (hoes) about fundamentals, (ii) underweight private information (with respect to the optimal statisti- cal weight), and (iii) are farther away from fundamentals than investors’ consensus. the same result obtains in our setup when liquidity trading is transient. a similar result also holds at the lie when liquidity trading is persistent. however, at the hie we find that the price is more strongly tied to fundamentals (as compared with investors’ consensus) and overweights average private information (as compared with the optimal statistical weight). therefore, the beauty contest feature of asset prices does not necessarily imply that prices are worse estimators of fundamentals compared to consensus; neither does it imply that prices exhibit inertia or react slowly to changes in the fundamentals. hence we can establish the limits of this beauty contest analogy for financial markets and refute the view that short-term trading always amplifies demand shocks or necessarily leads to uninformative prices or “excess” volatility. we also identify the circumstances in a related paper, we show that a similar conclusion holds in a model with long-term investors (see cespa and vives ( )). part of the debate over the consequences of short-term trading revolves precisely around its al- leged negative effect on the informativeness of asset prices (see, e.g., the “kay review of uk equity markets and long term decision making,” available at http://lawcommission.justice.gov.uk/docs/ http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf under which informed traders stabilize the market by counteracting the actions of liquid- ity traders (at the hie). finally, we deliver sharp predictions on asset pricing that are consistent with the received empirical evidence (including noted anomalies). a crucial hypothesis of our model is that liquidity trading displays persistence. this hypothesis can be viewed as a reduced-form assumption for the performance–flow rela- tionship’s effect on the holdings of mutual funds. coval and stafford ( ) show that mutual funds faced with aggregate redemption orders will curtail their positions and en- gage in “fire sales”. this dynamic generates a temporary and allegedly uninformed price pressure that reduces fund performance. as shown by evidence on the performance–flow relationship (chevalier and ellison ( ), sirri and tufano ( )), poor performance in turn breeds investors’ redemptions, thus engendering further fire sales. the implica- tion is that uninformed orders can display persistence. building on this intuition, lou ( ) tests a capital flow–based explanation for some well-known empirical asset pricing regularities and finds that mutual funds’ shareholdings display strong persistence at a quarterly frequency. campbell and kyle ( ) follow a different approach and disentan- gle the properties of the noise process from the properties of returns; these authors find that liquidity traders’ positions are highly persistent at an annual frequency. in sum, the persistence of liquidity trading appears to be a natural and plausible assumption that is backed by empirical evidence. the mechanism responsible for complementarities is as follows. suppose a risk-averse, short-term trader has a private signal on the firm’s fundamentals. his willingness to spec- ulate on that signal is directly related to how well he can estimate the next period’s price and, significantly, such willingness is also inversely related to the trader’s uncertainty about the liquidation price. indeed, the more volatile the price at which the investor un- winds, the riskier his strategy and the less willing to exploit his private signal the trader becomes. yet an average increased response to private information today, increases the price informativeness and reduces the residual variance of tomorrow’s price conditional on today’s price. this pushes up the response to the private signal today and may induce strategic complementarities in the responses to the private signals. for this to happen the variance reduction effect must be strong enough to overwhelm the usual substitution effect according to which a more informative price today decreases the weight put by the trader on his private signal in the estimation of tomorrow’s price. therefore, a trader’s willingness to act on private information not only depends on his uncertainty about the liquidation price but also affects that uncertainty. we argue that this two-sided loop kay-review-of-equity-markets-final-report.pdf ). http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf 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http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf may account for the existence of multiple stable equilibria that can be ranked in terms of liquidity, volatility, and informational efficiency. the variance reduction effect is potentially strong when liquidity trading is persis- tent. the crux of our argument revolves around a particular type of inference from the information (as reflected by prices) that arises in this case. if there is persistence then second-period investors can retrospectively assess their first-period inferences about the fundamentals—that is, based on the new evidence gathered in the second period. we therefore term this effect “retrospective inference”. in a market whose investors are both risk averse and asymmetrically informed, it is well-well known that the price impact of trades stems from the sum of an “inventory” component and an “inference” component. in a static market the two terms are positive, but in a dynamic market it is possible for retrospective inference to render the inference component negative. that effect dimin- ishes the price impact of trades, reducing the volatility of the asset price and boosting the response of traders to private information. the intuition is as follows. suppose that second-period informed investors observe a large demand for the asset. if in the first period these investors traded aggressively on their private information, then the first-period price is informative about the fundamentals. therefore, the bulk of the price adjustment to fundamentals must have already occurred in the first period. this reduces the likelihood that demand is being driven by informed trading and thereby makes it more likely that it is driven by liquidity trading. if there is persistence, then this result implies that a high demand for the asset from liquidity traders also affected the first- period aggregate demand —which further implies (for a given price realization) a lower expectation of the fundamentals. so in this case, a large aggregate demand realization leads second-period investors to revise downward their expectation of the liquidation value. this implies in turn that the inference component of the price impact offsets the inventory component, reducing the latter’s significance. the result is diminished first-period investor uncertainty about the unwinding price, which boosts the response of investors to private signals. we have therefore a self-fulfilling loop of strong reaction to first period private signals which leads to a high information equilibrium. the same logic leads to a low information equilibrium when one assumes that first-period investors trade weakly on their private signals. we show that if retrospective inference is present but the variance reduction effect that is, liquidity traders’ position are correlated across trading dates. the former captures the price variation due to the the change in asset exposure that investors experience when clearing the market; the latter captures the price change due to investors’ inferences from aggregate demand for the asset. moderately strong, then two extremal and stable equilibria arise: the lie and the hie. in the hie, volatility is low, liquidity is high, and prices closely reflect the underlying fundamentals; in the lie, volatility is high, liquidity is low, and prices reflect poorly underlying fundamentals. if retrospective inference and the variance reduction effect are very strong then the hie becomes unstable, in which case the only likely equilibrium to arise is the lie. our analysis shows that the strength of the retrospective inference loop depends on traders’ reliance on prices as a source of information for their decisions. suppose, for example, that private signals are much more precise than exogenous public information; then prices are relatively more informative, the loop is very strong, and the hie is unstable. when the public signal precision increases, the retrospective inference loop weakens and thereby stabilizes the hie. finally, when precision of the public signal increases further, the hie disappears, because the variance reduciton effect is weakened, and uniqueness occurs at the lie. thus, our paper shows that public information plays an active role in determining the type of market equilibrium when there is short-term trading. our model predicts that the lie arises under extreme values of public signal precision (which could be proxied by the number of analysts following a given security). the low- information equilibrium is characterized by: (i) a positive inference component of the price impact; (ii) momentum or reversal, depending on the strength of persistence; (iii) high expected returns from providing liquidity; (iv) prices that are far from the semi-strong efficient price; (v) strong short-horizon return predictability from order imbalances; and (vi) low volume accompanied by high levels of disagreement. for intermediate values of public signal precision, the hie can also arise. the high-information equilibrium features (i) a negative inference component of the price impact, (ii) mild momentum, (iii) low expected returns from liquidity provision, (iv) prices that are close to the semi-strong efficient price, (v) weak short-horizon return predictability from order imbalances, and (vi) high volume accompanied by low levels of disagreement. it is important to note that the autocovariance of short-term returns is always positive in the hie but is positive in the lie only when liquidity trading is sufficiently persistent. since the predictability of liquidity trading is an essential ingredient in multiple equilibria, it follows that momentum is a consequence of persistence. that being said, the patterns of prices and price informativeness implied by the two equilibria are markedly different. in particular, momentum along the hie (resp., lie) is a sign that prices are rapidly (resp., slowly) converging toward the full-information value. our model has the following implications: • when high trade volume is associated with informative prices and with low levels of disagreement, then this discriminates in favor of the hie, not only in relation to the lie but also in relation to alternative theories based on differences of opinions (do) models, in which disagreement is associated with high volume. • a negative covariance between conditional volatility of returns and volume does not rule out the applicability of rational expectations models (as suggested by banerjee ( ), for example) since it is consistent with ours. • a negative inference component of the price impact identifies the hie; the ob- servation of a reversal at short horizons identifies the lie (under the maintained hypothesis that our model holds). • if for “fragile” stocks – in the sense of greenwood and thesmar ( ) – there is a low transaction volume when there is high disagreement, then this would be evidence for a lie. similarly, a high transaction volume for non-fragile stocks about which there are low levels of disagreement, constitutes evidence for a hie. the rest of the paper is organized as follows. after discussing the related literature, we analyze the static benchmark. in section iii we study the two-period model, relate it to the beauty contest literature, and present the multiplicity result. we then derive asset pricing implications and use our model to interpret some aspects of the recent financial crisis. the paper’s final section summarizes our results and discusses their empirical implications. most formal proofs are relegated to the paper’s appendix. an online appendix offers a detailed robustness analysis of the model. i related literature our results are related to—and have implications for—three strands of the literature. first, our paper is related to the literature that investigates the relationship between the effect of short-term investment horizons on prices and the reaction of investors to their private signals (see singleton ( ), brown and jennings ( ), froot, scharfstein, and stein ( ), dow and gorton ( ), vives ( ), cespa ( ), vives ( ), and this finding has an empirical counterpart: some spread decomposition models find that, consistently with our hie prediction, the spread’s inference component can be negative. albagli ( )). if prices are semi-strong efficient (as in vives ( )), then traders do not require compensation for increasing their exposure to the asset and so the inventory component of the price impact disappears. as a consequence, the retrospective inference loop breaks down and a unique equilibrium obtains. brown and jennings ( ) analyze a model in which prices are not semi-strong efficient, investors have a short-term horizon, and liquidity trading can be correlated. their work provides a rationale for “techni- cal analysis” that shows how, absent semi-strong efficiency, the sequence of transaction prices is more informative—about the final payoff—than is the current stock price. we argue that, in the absence of semi-strong efficiency, if liquidity trading is correlated then second-period investors can retrospectively evaluate their first-period inferences. this opportunity for reassessment generates strategic complementarities in the use of private information and can also lead to multiple equilibria. other authors find that multiple equilibria can arise in the presence of short-term traders. in this regard, part of the literature assumes an infinite horizon economy. un- der that assumption, multiplicity arises from the bootstrap nature of expectations in the steady-state equilibrium of an overlapping generations (olg) model in which investors live for two periods. spiegel ( ) studies the model with symmetric information. watanabe ( ) extends the model of spiegel ( ) to account for the possibility that investors have heterogeneous short-lived private information. other authors generate multiple equilibria in finite-horizon economies. zhang ( ) shows that short-term trad- ing generates multiple equilibria that can be ranked in terms of price informativeness. however, multiplicity in that paper arises at the information acquisition stage, whereas we find multiplicity in the response to private information. furthermore, public informa- tion in the lie crowds out the production of private information, which is the opposite of what happens in our case. along similar lines, avdis ( ) finds that short-term trading can generate multiple equilibria in information acquisition. finally, chen, huang, and zhang ( ) analyze a model with short-term trading and in which traders receive sig- nals of different precision. these authors show that, even with transient liquidity trading, multiple equilibria can arise in the response to private information. this is so because in the absence of private information, our model is akin to a finite-horizon version of spiegel ( ); hence, in this case we can show that a unique equilibrium obtains. in his case, too, the analysis concentrates on the steady-state equilibrium; his results are therefore not directly comparable to ours. furthermore, information on fundamentals is short lived in watanabe ( ) whereas in our model it is long lived; this difference substantially changes the nature of the inference problem faced by first-period investors. in related research, dennert ( ) concentrates on the steady-state solution in his olg extension of grossman and stiglitz ( ). private information is short lived in this setup also. the uncertainty reduction effect of an increase in the response to private information is boosted by the dispersion of private precisions. the second stream of literature to which our paper relates is the work that addresses the influence of higher-order expectations on asset prices (see allen, morris, and shin ( ), nimark ( ), bacchetta and van wincoop ( ), kondor ( )). bacchetta and van wincoop ( ) study the role of hoes in the foreign exchange market. they show that such expectations worsen the signal extraction problem that investors face when observing exchange rate fluctuations that originate from trades based on hedging motives and fundamentals information. in our setup this deterioration occurs at the lie; at the hie, in contrast, investors’ strong reaction to private information makes signal extraction less of a problem. it is noteworthy also that, in contrast with do models (see, e.g., kandel and pearson ( ), banerjee ( ), kondor ( )), we find that at the hie, in which there is low disagreement, volume is large and the conditional volatility of returns is negatively related to expected volume. finally, this paper is related to the literature on limits to arbitrage. in that regard, our multiplicity result is reminiscent of de long et al. ( ), but in a model with rational traders and a finite horizon. thus, our paper naturally relates to the strand of this literature that views limits to arbitrage as the analysis of how “non-fundamental demand shocks” impact asset prices in models with rational agents (gromb and vayanos ( ), vayanos and woolley ( )), emphasizing the role of liquidity shocks persistence. our model also predicts that momentum is related to a high volume of informational trading, which is in line with the evidence presented in llorente et al. ( ). some have claimed that limits to arbitrage capital are responsible for crashes and meltdowns (see duffie ( ); see also khandani and lo ( ) for the august quant meltdown). in our model, meltdowns can be explained in terms of a transition from the high- to the low-information equilibrium. ii the static benchmark consider a one-period stock market in which a single risky asset (of liquidation value v) and a riskless asset (of unitary return) are traded by a continuum of risk-averse, informed investors in the interval [ , ] and also by liquidity traders. we assume that v ∼ n(v̄,τ− v ). investors have constant absolute risk aversion (cara) preferences (we use γ to denote in a static trading model, ganguli and yang ( ) discusses complementarities in information acquisition. the risk-tolerance coefficient) and maximize the expected utility of their wealth: wi = (v−p)xi. before the market opens, each informed investor i obtains private information on v, receiving a signal si = v + εi, εi ∼ n( ,τ− ε ), and submits a demand schedule (generalized limit order) x(si,p) to the market; indicating the investor’s desired position in the risky asset for each realization of the equilibrium price. assume that v and εi are independent for all i and that error terms are also independent across investors. liquidity traders submit a random market order u (independent of all other random variables in the model), where u ∼ n( ,τ− u ). finally, we adopt the convention that the average signal∫ si di is equal to v almost surely. in other words, errors cancel out in the aggregate:∫ εi di = . in the cara-normal framework just described, a symmetric rational expectations equilibrium (ree) is a set of trades contingent on the information that investors have, {x(si,p) for i ∈ [ , ]}, and on a price functional p(v,u) (measurable in (v,u)) such that investors in [ , ] optimize (given their information) and the market clears: ∫ xi di + u = . given this definition, it is easy to verify that a unique and symmetric equilibrium in linear strategies exists in the class of equilibria with a price functional of the form p(v,u) (see, e.g., admati ( ), vives ( )). the equilibrium strategy of cara investor i is given by x(si,p) = γ e[v|si,p] −p var[v|si,p] . letting τi ≡ (var[v|si,p])− and denoting by αe = τε/τi the optimal statistical (bayesian) weight given to private information in e[v|si,p], we have that γτi = (a/αe), where a = γτε, ( ) denotes the responsiveness to private information of investor i. note that a is independent of the variance of the price or of liquidity trading. this is because var[v|si,p] cancels in the numerator and denominator of x(si,p). if market clearing is imposed then the we assume without loss of generality that, with cara preferences, the nonrandom endowment of informed investors is zero. the unique equilibrium in linear strategies of this model is symmetric. this convention is justified in section . of the technical appendix to vives ( ). equilibrium price is given by p = ∫ ei[v] di + αe a u ( ) = e[v|p] + Λe[u|p], ( ) where e[u|p] = a(v −e[v|p]) + u and Λ = vari[v] γ . ( ) equations ( ) and ( ) show that the price can be represented in two different ways. ac- cording to the representation in ( ), the price reflects not only the consensus opinion that investors hold about the liquidation value but also the effect of demand from liquid- ity traders (multiplied by their risk tolerance–weighted uncertainty over the liquidation value). indeed, owing to cara and normality, in a static market an investor’s demand is proportional to the expected gains from trade, e[v|si,p]−p. because the price aggregates the demand of all investors, it reflects the consensus opinion ∫ ei[v] di that is shocked by the orders of liquidity traders. according to ( ), the equilibrium price reflects investors’ estimates of the fundamen- tals v (the so-called semi-strong efficient price e[v|p]) and of liquidity traders’ demand u; risk-averse investors demand compensation for accommodating liquidity traders’ orders. under asymmetric information, that demand is not perfectly observable from the price. therefore, such compensation is increasing in an investor’s estimate e[u|p] scaled by Λ. it follows from ( ) that, for a given e[u|p], greater investor uncertainty about the liquidation value or about the risk involved is associated with higher Λ and greater compensation. thus Λ captures the “inventory” component of market liquidity. liquidity traders’ orders have an additional effect on the price through their impact on the semi-strong effi- cient price e[v|p]. this effect induces an inference component that adds to the inventory component, implying that the (reciprocal of) market liquidity can be written as λ ≡ ∂p ∂u = Λ + ( −αe) aτu τ , when risk-averse investors accommodate an expectedly positive demand of liquidity traders, the former require compensation for risking that the liquidation value ends up being higher than the public expectation (conversely, if e[u|p] < then investors insist on a price that is lower than e[v|p]—to cover the risk that v < e[v|p]). such compensation is increasing in the uncertainty faced by investors (as captured by Λ) and in the the extent of their anticipated exposure to the liquidity traders’ shock (i.e., their expected inventory e[u|p]). where τ = /var[v|p] = τv + a τu. we remark that, all else equal, in a static setup the inference component magnifies the price impact of liquidity traders’ orders. iii a two-period market with short-term investors consider now a two-period extension of the market analyzed in the previous section. at date (resp., ), a continuum of short-term investors in the interval [ , ] enters the market, loads a position in the risky asset, and then unwinds that position in period (resp., ). investor i has cara preferences (we denote by γ the coefficient for common risk tolerance) and maximizes the expected utility of her short-term profit πin = (pn+ − pn)xin for n = , with p = v̄ and p = v. the short-term horizons of investors can be justified on the grounds of incentive reasons related to performance evaluation or of the difficulties associated with financing long-term investment when there are capital market imperfections (see holmström and ricart i costa ( ) and shleifer and vishny ( )). an investor i who enters the market in period receives a signal si = v+εi that she recalls in the second period, where εi ∼ n( ,τ− ε ) and where v and εi are independent for all i. we assume further that in the second period a signal sp = v+η is publicly disclosed to the market, where η ∼ n( ,τ− η ) is independent of both v and εi for all i. the public signal introduces an additional source of public information on the fundamentals (i.e., besides the equilibrium prices) whose informativeness is exogenous to the trading process. the real-world counterpart of this assumption is any public announcement about the asset’s value (e.g., an earnings announcement, analysts’ consensus forecast of earnings). once again we adopt the convention that, given v, the average private signal ∫ si di equals v almost surely and so errors cancel out in the aggregate: ∫ εi di = . we restrict our attention to equilibria in linear demand functions. we denote by x (si,p ) = a si − ϕ (p ) and x (si,sp ,p ,p ) = a si + bsp − ϕ (p ,p ) an investor’s desired position in the risky asset for each realization of the equilibrium price at (respec- tively) dates and . the constants an and b denote, respectively, the weight an investor gives to private information at date n and the weight she gives to the public signal. the function ϕn(·) is a linear function of the equilibrium prices. the adverse selection effect is a consequence of the signal extraction problem that dealers face in this market: since a > , if investors on average have good news then they buy the asset and so e[v|p] increases, reflecting that information. however, this effect cannot be distinguished from the buying pressure of liquidity traders, which also has the effect of increasing e[v|p]. as before, we assume (w.l.o.g.) that the nonrandom endowment of investors is zero. the equilibria in linear strategies of this model are symmetric. the position of liquidity traders is assumed to follow a first-order autogressive or ar( ) process: θ = u , θ = βθ + u ; ( ) here β ∈ [ , ] and {u ,u } is an independent and identically distributed (i.i.d.) random process (independent of all other random variables in the model) with un ∼ n( ,τ− u ). other authors have adopted this assumption for liquidity traders, including singleton ( ), campbell and kyle ( ), he and wang ( ), biais, bossaerts, and spatt ( ), and cespa and vives ( ). if β = , then {θ ,θ } follows a random walk and we are in the usual case of independent liquidity trade increments: u = θ − θ is independent of u (kyle ( ), vives ( )). if β = , then liquidity trading is i.i.d. across periods; this is the case considered by allen, morris, and shin ( ). persistent liquidity trading is taken as a primitive of the model, but such trading can be shown to arise endogenously in a model where liquidity traders are replaced by rational hedgers with different investment horizons (see cespa and vives ( )). persistence in liquidity trading can be given several possible interpretations, depend- ing on the frequency of observations. at a daily or intra-daily frequency, to assume persis- tence is a simple way to capture the need of liquidity traders to break down a large order into a series of smaller orders and thereby minimize price impact; as such, this assumption is consistent with several empirical findings (e.g., griffin, harris, and topaloglu ( ), chordia and subrahmanyam ( )). at a lower frequency, liquidity trading persistence can be seen as a reduced-form assumption capturing the performance–flow relationship’s effect on the holdings of mutual funds. coval and stafford ( ) show that mutual funds faced with aggregate redemption orders engage in fire sales (resp., purchases), creating more specifically, suppose that we replace the first-period liquidity traders with a set of hedgers in the interval [ , ] and that each of these hedgers receives an idiosyncratic and normally distributed endowment shock θi that is independent of the model’s other random variables. all hedgers take a position in the asset at date . however, a fraction β of them (denoted hl) have a long-term horizon and hold their positions until the liquidation date; the complementary fraction (denoted hs) has a short- term horizon, and these hedgers liquidate their positions at date . under this model we can show that, in a linear equilibrium, the persistence coefficient corresponds to the β-weighted relative responsiveness to the endowment shock displayed by hl (i.e., as compared with the average response of both hl and hs). since the responsiveness of hedgers is endogenous and since information is asymmetric, it follows that that in this case a participation externality (similar to the one in admati and pfleiderer ( ), pagano ( ), and dow ( )) arises. namely, hedgers’ decisions to trade in the first period depend on market liquidity, which in turn depends on hedgers’ decisions to trade. this new loop can generate multiplicity with different levels of hedging activity. contemporaneous, uninformed, and temporary negative (resp., positive) price pressure. coupling this result with the evidence that capital flows in and out of mutual funds are strongly related to past performance (chevalier and ellison ( ), sirri and tufano ( )), negative shocks to the capital of mutual funds can affect those funds’ trades and thus have a negative (resp., positive) effect on their performance through feeding back to the funds’ capital outflows (resp., inflows). empirical evidence of liquidity trading persistence has been obtained in two ways. campbell and kyle ( ) disentangle the properties of the noise process from the prop- erties of returns. these authors examine annual aggregate returns of index data in the united states and then attempt to fit the properties of the time series with different mod- els that feature noise. they find that, at a yearly level, noise traders’ positions are highly persistent (from % to % of the noise remains after one year). an alternative strategy is to look at the f filings of mutual funds that face negative or positive net inflows and are thus led to trade for non-informational purposes (coval and stafford ( )). this is the approach taken by lou ( ), who finds that mutual funds’ shareholdings display strong persistence at a quarterly frequency. we denote by ei [y ] = e[y |si,p ] and vari [y ] = var[y |si,p ] the expectation and variance of the random variable y formed by a date- investor using private and public information; e [y ] = e[y |p ] and var [y ] = var[y |p ] denote the same case but when only public information is used. similar definitions for date- investors yield ei [y ] = e[y |si,sp ,p ,p ] and vari [y ] = var[y |si,sp ,p ,p ] as well as e [y ] = e[y |sp ,p ,p ] and var [y ] = var[y |sp ,p ,p ]. the variables τn and τin denote the precision of investor forecasts of v based (respectively) only on public information and on both public and private information; thus, τn = ( /varn[v]) and τin = ( /varin[v]). letting αen = τε/τin, we have ein[v] = αensin + ( −αen )en[v]. we now derive the informational content of prices in a linear equilibrium. consider a candidate linear (symmetric) equilibrium where xi = a si−ϕ (p ) and xi = a si +bsp − ϕ (p ,p ) for ϕn(·) a linear function. denote by z ≡ a v + θ the noisy informational addition about v generated by informed investors in period (i.e., the “informational content” of the first-period order flow). similarly, put ∆a ≡ a − βa and denote investors’ second-period informational addition by z ≡ ∆a v + u . we now show that, at a linear equilibrium, p is observationally equivalent (o.e.) to z and that, given sp , the coval and stafford argue in more detail that fire sales occur in mutual funds that follow specialized investment strategies and that exhibit considerable overlap in their holdings. easley, hvidkjaer, and o’hara ( ) develop a methodology to estimate the probability of informed trading from transaction data. sequence {z ,z } is o.e. to {p ,p }. if we let xn ≡ ∫ xin di and impose market clearing in the first period, then (by our convention) the implication is that x + θ = ⇐⇒ a v + θ = ϕ (p ). ( ) in the second period, the market-clearing condition is x + βθ + u = ⇐⇒ x −βx + u = ⇐⇒ a v + bsp −ϕ (p ,p ) −β(a v −ϕ (p )) + u = ⇐⇒ ∆a v + u = ϕ (p ,p ) −βϕ (p ) − bsp ; ( ) in the second line we have used ( ), and by ∆a = a − βa we denote the β-weighted net trading intensity of second-period informed investors. from ( ) and ( ) it is easy to see that z is o.e. to p and that, given sp , {z ,z } is o.e. to {p ,p }. hence e [v] = τ− (τvv̄+a τuz ), e [v] = τ − (τ e [v] +τηsp + ∆a τuz ), var [v] ≡ τ − = (τv +a τu) − , var [v] ≡ τ− = (τ + τη + (∆a ) τu) − , ein[v] = τ − in (τnen[v] + τεsi), and varin[v] ≡ τ− in = (τn + τε) − . we shall now relate price formation to the keynes’s notion of a beauty contest. then we look at the retrospective inference mechanism that we associate with persistent liquidity trading and characterize equilibria, their stability properties, and trading strate- gies. in this way we demonstrate the limits of the beauty contest analogy for financial markets. we end section iii with a robustness analysis. a prices and beauty contests here we give an expression for the equilibrium price that highlights the dependence of that price on investors’ higher-order expectations about fundamentals (cf. allen, morris, and shin ( )). when there is persistence, liquidity traders’ orders at time n also affect the demand for the asset at time n+ . so in a two-period model, first-period investors use their private information also to infer the demand of liquidity traders from the first-period price. as a result, the latter is driven by investors’ hoes about fundamentals and by their average expectations about liquidity trading. this result, in turn, has implications for the informational properties of the price. let us denote by ēn[v] ≡ ∫ ein[v] di the consensus opinion about the fundamentals at time n, where ēn[v] = αenv + ( − αen )en[v]. starting from the second period, if we impose market clearing then ∫ x (si,sp ,p ,p ) di + θ = . because of cara and normality, we have x (si,sp ,p ,p ) = γvari [v] − (ei [v] − p ). substituting this expression into the market-clearing equation and solving for the equilibrium price now yields p = ē [v] + vari [v] γ θ . ( ) similarly, imposing market clearing in the first period we have ∫ x (si,p ) di + θ = ; solving for the equilibrium price then yields p = ē [p ] + vari [p ] γ θ . ( ) substituting ( ) and then rearranging, we obtain p = ē [ ē [v] + vari [v] γ θ ] + vari [p ] γ θ = ē [ē [v]] + β vari [v] γ ē [θ ] + vari [p ] γ θ . ( ) according to ( ), three terms constitute the first-period price: investors’ second-order average expectations over the liquidation value (ē [ē [v]]), the risk-adjusted effect of the first-period stock of liquidity trades (θ ), and investors’ average expectations over first- period liquidity trades (ē [θ ]). those latter expectations arise because p depends on θ , which in turn is correlated with θ when β > . thus, investors in period are also interested in estimating θ . expression ( ) implies that, because of persistence in liquidity trading, the weight of the price on investors’ average information is the sum of two terms. the first term captures the effect of hoes on v, and the second reflects the effect of investors’ average expectations concerning θ . we have that ē [ē [v]] = ᾱe v + ( − ᾱe )e [v]; ē [θ ] = a ( −αe )(v −e [v]) + θ . here ᾱe = αe ( − (τ /τ )( − αe )), and a denotes first-period investors’ average responsiveness to private information. so given ( ), the implication is that the total when computing ē [θ ] we have z = ei [z ] = a ei [v] + ei [θ ], and ei [θ ] = z − a ei [v] = a (v −ei [v]) + θ . computing average expectations yields ē [θ ] = a (v − ē [v]) + θ . finally, using ē [v] = αe v + ( −αe )e [v] yields the expression in the centered formula above. weight of the price on average private information is given by αp = ᾱe + β vari [v] γ a ( −αe ). ( ) observe that ᾱe < αe for any β. therefore, if liquidity trading is transient (β = ) then the first-period price places more weight on public information than does the optimal statistical weight. this finding is in line with allen, morris, and shin ( ), who prove that if information is heterogeneous then prices reflect investors’ hoes about the final payoff. in this case, the law of iterated expectations does not hold and investors’ forecasts overweight public information (in the sense that αp = ᾱe < αe ). the reason is that investors anticipate the average market opinion while knowing that this opinion depends also on the public information observed by other investors. in section iii.e we show that the price is then systematically farther away (than the consensus) from fundamentals. if liquidity trading is persistent, however, then p also reflects investors’ average expectations about θ . hence another term is added to ᾱe in the expression for αp given by ( ). we argue in section iii.e that this additional term can reverse the conclusion we derived under transient liquidity trading. b retrospective inference and equilibrium prices we start by giving a general description of the equilibrium price function providing three equivalent expressions for prices that highlight different properties of the model. proposition . at a linear equilibrium, the price is given by pn = αpn ( v + θn an ) + ( −αpn )en[v], ( ) where θn = un + βθn− and where an and αpn denote the responsiveness to private in- formation exhibited at period n by investors and by the price, respectively (see equations (a. a), (a. b), (a. ), and (a. )). we have that αp = αe < . according to ( ), at period n the equilibrium price is a weighted average of the market expectation about the fundamentals v (the semi-strong efficient price) and a noisy market signal about v that depends on the response to private information. rearranging this expression yields pn −en[v] = αpn an (an(v −en[v]) + θn) = Λnen[θn] ( ) for Λn ≡ αpn/an, which implies that there is a discrepancy between pn and en[v]. as in the static market (see ( )), this discrepancy reflects a premium that is proportional to the expected stock of liquidity trading that investors accommodate at n. the result is our second equilibrium price expression as follows. corollary . at a linear equilibrium, the price incorporates a premium above the semi- strong efficient price: pn = en[v] + Λnen[θn], ( ) where Λ = vari [v]/γ and Λ = vari [p ] γ + βΛ . ( ) a comparison of ( ) with ( ) reveals that short-term trading affects the inventory component of liquidity. in a static market, investors who absorb the demand of liquidity traders are exposed to risk stemming from the randomness of v. in a dynamic market, however, short-term investors at date face the risk due to the randomness of the next- period price (i.e., the price at which they unwind). to the extent that liquidity trading displays persistence, informed second-period investors absorb part of the first-period liq- uidity traders’ positions; this dynamic contributes to first-period investors’ uncertainty about p , yielding ( ). we can use ( ) to show that, as in the static benchmark, under asymmetric informa- tion the price is affected not only by the inventory component Λn but also by an inference component. this claim is formalized in our next corollary. corollary . let a = . at a linear equilibrium, p = λ z + ( −λ a )v̄ and ( a) p = λ z + τη τi sp + γτ e [v] + βz γτi . ( b) here λn denotes the price impact of trades in period n = , : λn ≡ ∂pn ∂un = αpn an + ( −αpn ) ∆anτu τn . ( ) according to ( ), the inference component of liquidity at n = is captured by ( −αp ) ∆a τu τ . ( ) as shown in ( ), a dynamic market differs from the static benchmark in that the sign of this component depends on the β-weighted net position of informed investors; thus the net trading intensity ∆a = a −βa . as a result, the effect of private information in the second period depends on the change in informed investors’ positions, where this change is measured by ∆a = a −βa . the implication is that the sign of the inference component depends on the magnitude of a as compared with a /β. therefore, the first- period response to private information affects the informational innovation extracted from p and also (when β > ) the one extracted from p —that is, both z and z —as well as the sign of the inference component in λ . when β > the door is open to a negative inference component in the second period when a is large since in this period investors retrospectively reassess the first period inference about the fundamentals based on the new evidence gathered. suppose that second-period informed investors observe high demand for the asset (i.e., z high). if a is large then the first-period price is quite informative about v (since z = a v + θ ). hence (i) most of the price adjustment to fundamentals information must have occurred in the first period and (ii) demand is likely to be driven by liquidity trading. since β > , it follows that high demand for the asset from liquidity traders also affected the first-period aggregate demand. but for a given price realization p , that would imply a lower expectation of the fundamentals. indeed, if a is so large that ∆a < , then a large aggregate demand realization leads second-period investors to revise downward their expectations of the liquidation value because a large z = ∆a v + u is bad news about v when ∆a < . in this case the inference component in λ is negative and offsets the inventory component. if instead a is small, the first period price is poorly informative about v, and a second period large realization z is more likely to come from informed investors. for β > this reinforces the belief that low liquidity traders’ demand affected the first period demand for the asset and, for a given price realization p , implies a higher expectation of the fundamentals (since ∆a > ). in this case, the inference component is positive and adds to the inventory component, increasing λ . we have that αp = αe and so −αp ∈ ( , ). this is because, for given p and z = a v + θ , a higher value for θ provides stronger evidence that the fundamentals v is low. in summary, when liquidity trading displays persistence, second period investors can retrospectively reassess the first period inference about the fundamentals, based on the new evidence gathered in the second period, affecting the inference component of second period price impact of trade (λ ). we thus term this effect “retrospective inference”. c equilibrium characterization short horizons create a dependence of a on the residual variance of p given p , generating an uncertainty reduction effect when a increases. the reason is that short-term investors in the first period trade according to x (si,p ) = γ ei [p ] −p vari [p ] =⇒ a = γ weight to si in ei [p ] vari [p ] . ( ) by this implication, a is directly related to the relevance of the private signal to forecast p and inversely related to investors’ uncertainty about p . two effects are present that, contrary to the static case, do not cancel each other. on the one hand, we have the usual substitution effect whereby a higher on average a leads to a more informative price in period (higher τ and τi ), and therefore a lower weight to private information τ�/τi in ei [p ], which tends to depress a . on the other hand, a higher average a and larger τ leads to a lower vari [p ], which tends to raise a . this is a source of strategic complementary in the responses to private information. with short-horizons, this uncertainty reduction effect also works through λ . this is because, first period investors are interested in forecasting p and, for any public signal, the extent to which p differs from p depends on λ (see ( b)). therefore, a higher λ (in absolute value) will, ceteris paribus, increase first-period investors’ uncertainty about p and depress a . recall that when β > it is possible that ∆a < when a is high enough, implying that the inference component in λ offsets the inventory component. in this case, the second- period price impact of trade is small, which diminishes first-period investors’ uncertainty about p and so boosts their response to private signals. hence, the variance reduction (second) effect dominates the substitution (first) effect and a high level of a can be sustained in equilibrium. at the same time, a lower level of a is also self-fulfilling. indeed, a low a generates a low τ and a high residual variance for p given p which makes the low a self-fulfilling. in this case we have ∆a > (even if β > ) and the retrospective inference plays an anlaogous role as the “adverse fundamental” effect in goldstein and yang ( ). second period price impact of trade (λ ) is high, augmenting the residual variance of p . summarizing, investors’ willingness to speculate on private information not only de- pends on their uncertainty about the liquidation price, but also affects that uncertainty. this two-sided loop in the determination of a gives rise to strategic complementarities in the use of private information, which can yield multiple equilibria. the following proposition characterizes linear equilibria and provides suffcient conditions for multiple equilibria to exist. those conditions imply that the variance reduction effect is strong enough. proposition . suppose τη > . • if β > / , γ τετu > ( β − )/( − β), and τη ≤ τ̂η (for some τ̂η > defined in the appendix, see (a. c)), there always exist at least three linear equilibria where a = γτε and a ∈{a∗ ,a∗∗ ,a∗∗∗ }, with a∗ ∈ ( ,a ), a∗∗ ∈ ( + γτua γβτu , + γτua γβτu ) , a∗∗∗ > + γτua γβτu , implying a∗ < a < a ∗∗ < a ∗∗∗ . when a =   a ∗ , then a −βa∗ > , and λ ∗ > , a∗∗ ,a ∗∗∗ , then a −βa∗∗ < , and λ ∗∗ < . ( ) along these equilibria: τ∗n < τ ∗∗ n < τ ∗∗∗ n , n = , . ( ) • if β = , there exists a unique equilibrium with a = γτε, γ a τu(a τu + τε + τη) + γ τu(a τu + τε + τη) < a∗ < a , and λ∗ > . according to this proposition, multiplicity requires that private information be strongly reflected in prices (γ τετu > is sufficient), persistence (β) is high, and public precision (τη) is low. all of these conditions strengthen the retrospective inference and the de- scribed uncertainty reduction effect loop. a contrario, for example, a higher precision of the public signal makes p more dependent of sp and less on p and therefore the impact of τ on the residual variance of p is lessened. a Ψ�a � lie hie iie figure : the best-response mapping ( ) for β = , γ = / , τu = τv = , τη = , and τε = . . in view of ( ), we refer to the three equilibria described in proposition as (respec- tively) the low-, intermediate-, and high-information equilibrium: lie, iie, and hie. in the appendix we show that first-period equilibrium responsiveness is obtained as a fixed point of the following function: ψ(a ) = γ (λ ∆a + τη/τi )αe (λ ∆a + τη/τi ) /τi + λ /τu + τη/τ i . ( ) numerical analysis shows that this function crosses the -degree line at most three times, which suggests that the three equilibria described in proposition are the only ones that can arise (see figure ). our numerical results show further that these equilibria can be ranked in terms of second-period price impact (λ ), inventory component of liquidity (Λn), and conditional volatility (var [p ]). the following result gives more details. numerical result . when multiple equilibria arise, these inequalities hold: λ∗ > |λ ∗∗ | > |λ ∗∗∗ |; ( a) Λ∗n > Λ ∗∗ n > Λ ∗∗∗ n ; ( b) var [p ] ∗ > var [p ] ∗∗ > var [p ] ∗∗∗. ( c) along the hie, ∆a < and the inference component of liquidity is negative. this finding is consistent with second-period traders revising downward their first-period as- sessment of the payoff in the presence of a positive demand shock (i.e., engaging in retrospective inference). this result is consistent also with the findings of some spread decomposition models (e.g., huang and stoll ( ), van ness, van ness, and warr ( ), henker and wang ( )) in which the adverse selection component of the spread can be negative. thus, our model provides a theoretical justification for this empirical finding. in figure we display the effects of a change in the values of public and private signal precision, persistence, and liquidity traders’ demand precision on the best response ( ). as the graphs show, uniqueness always occurs at the lie and requires high public pre- cision or low private precision, persistence, or liquidity traders’ precision. intuitively, in all of these cases the endogenous public signal (the price) becomes relatively less in- formative than the exogenous public signal (sp ), leading second-period investors to rely less on price information. this dynamic weakens strategic complementarity by softening the self-reinforcing uncertainty reduction loop resulting from retrospective inference and thereby yields a unique equilibrium. it is worth noting that it can be checked that the best response ψ(·) is downward sloping when β = . in figure we show that the effect of an increase in public signal precision on a depends on the equilibrium that arises. along the hie (resp., lie), a larger τη leads to a decrease (resp., increase) in a . the reason for this result is that a more precise public signal reduces traders’ reliance on price information when forecasting the fundamentals. thus, along both equilibria, the effect of retrospective inference is weaker in the second period. in the hie (lie) this weakened effect increases (decreases) first-period investors’ uncertainty about p , leading to a decrease (increase) in a . it is worth noting that huang and stoll ( ) assumes uninformed market orders to be generated by an ar( ) process, and the estimated parameter of that process turns out to be positive and close to. negative inference components also occur in different spread decomposition models. for example, hamm ( ) investigates the effect of exchange-traded funds on the liquidity of underlying stocks and estimates a spread decomposition model based on madhavan, richardson, and roomans ( ). in several of her findings, the inference component of the spread is negative—leading to the exclusion of such “out-of-range” observations. see also foucault, pagano, and röell ( ), ch. . . . public precision has little effect on the equilibrium ex ante, while the degree of risk tolerance has an effect similar to that of private precision. along the hie, second-period investors facing a large positive demand for the asset will adjust their estimate of the fundamentals downward, which implies that the inference component of λ is negative. other things equal, a more precise public signal reduces the absolute value of the inference component, which works to increase first-period investors’ uncertainty about p . in the lie, the converse statement holds. a Ψha l ΤΗ = ΤΗ = (a) a Ψha l ΤΕ = ΤΕ = . (b) a Ψha l Β=. Β= (c) a Ψha l Τu = . Τu = (d) figure : comparative statics. we plot the best response ( ) for the parameters’ value of figure (in orange) and show the effect of a change in the values of τη, τε, β, and τu (dashed, blue curve). in panel (a) we increase public signal precision to τη = ; in panel (b) we decrease private signal precision to τε = ; in panel (c) we decrease liquidity traders’ persistence to β = . , and in panel (d) we decrease the precision of liquidity traders’ demand to τu = . . if the public signal is totally uninformative then, for β > , the retrospective inference and variance reduction loop becomes extremely strong. in this case, the best response ( ) becomes discontinuous at the iie (which therefore disappears; see figure ) and so we always obtain two equilibria that can be computed in closed form. this claim is formalized in our next corollary. corollary . suppose τη = . • if β > then there always exist two linear equilibria, where a = γτε and a ∈ a Ψha l ΤΗ = ΤΗ = ΤΗ = � ΤΗ = � ΤΗ = figure : the best-response mapping ( ) when the public signal’s precision ranges within the set { , / , / , , }. the other parameter values are β = , γ = / , τu = τv = , τε = . , and τη = . when τη = , note that ψ(·,τη) diverges at the point â ≡ ( +γτua )/(γβτu) and the iie disappears. for τη > , we have ψ(â , . ) = . , ψ(â , . ) = . , ψ(â , ) = . , and ψ(â , ) = . . {a∗ ,a∗∗∗ } for a∗ < a < a∗∗∗ (see (a. ) and (a. ) for explicit expressions). if a =  a ∗ then a −βa∗ > and λ ∗ > (lie), a∗∗∗ then a −βa∗∗∗ < and λ ∗∗∗ < (hie). furthermore, |λ∗∗∗ | < λ ∗ , Λ ∗∗∗ n < Λ ∗ n, prices are more informative, and var [p ] is lower along the hie. • if β = , then there exists a unique equilibrium with a = γτε and a∗ = γa τu + γa τu < a . remark . it is possible to show (as in vives ( )) that a unique equilibrium arises when prices are set by a sector of competitive and risk-neutral market makers. in this case the market makers do not require compensation (for inventory risk) in order to clear the market, and prices are semi-strong efficient. the uncertainty reduction effect of an increase in a is present when β > but weakened, which ensures uniqueness. it is also possible to show that the equilibrium is unique when investors have no private information (τε = ). in this case our model is akin to grossman and miller ( ) and investors trade only to accommodate liquidity traders’ orders. prices are therefore invertible in the latter’s demand and retrospective inference does not arise, with price informativeness depending only on prior precsion. remark . we can draw a parallel between our model and models in which investor actions have a feedback effect on the asset’s value. in papers that feature such models (e.g., ozdenoren and yuan ( ), bond, goldstein, and prescott ( ), dow, goldstein, and guembel ( ), goldstein, ozdenoren, and yuan ( )), complementarities-driven multiplicity of equilibria arises also from the effect of the price on the asset’s value. in our paper, the price at n = (i.e., p ) represents the asset’s value from the perspective of investors at n = , and their trading also affects p . this dynamic corresponds to the feedback effect from prices to values in a one-period feedback model. bond, goldstein, and prescott ( ) show that, if agents use market prices when deciding on corrective actions (as when the board considers firing the ceo in response to a low stock price), then prices adjust to reflect this use and may thus become less revealing. in ozdenoren and yuan ( ), prices are informative about both the fundamentals and the likelihood of coordination among informed investors. multiple equilibria arise when the price is more informative of the coordination motive than of the fundamentals. in their paper, the feedback effect’s strength depends on the sensitivity of asset value to investment in the risky asset. the parallel in our model is the degree of persistence in liquidity trading. in both models, multiplicity tends to arise when the feedback effect is strong. much as in our model, in ozdenoren and yuan ( ) there are multiple equilibria also when the precision of private information is high and base liquidity trading low. yet unlike their study, in which an increase in public precision leads to a higher coordination motive and multiple equilibria, our model (with no coordination motive) yields the opposite result. d stability in this section we use the best response ( ) to perform a stability analysis of the equi- libria. toward that end, consider the following argument. assume that the market is at an equilibrium point ā and so ā = ψ(ā ). suppose now that a small perturbation to ā it is easy to see that in equilibrium a = γ/ ( τ− � + τ − ) and therefore we have always that ∆a > and λ = τu∆a /τ > . occurs. as a consequence, first-period investors modify the weight they give to private information; then the aggregate weight becomes ā′ = ψ(ā ′ ). if the market returns to the original ā then—according to the best-reply dynamics with the best-response function ψ(·)—the equilibrium is stable; otherwise, it is unstable. hence we can say that, in a stable (unstable) equilibrium, if investors other than i put a lower weight on their signals then (i) the price is noisier and (ii) investor i reacts by increasing less (more) than propor- tionally the weight on his own signal and so contributing less (more) than proportionally to restoring price informativeness. formally, we have the following definition. definition (stability). an equilibrium is stable (unstable) if and only if its correspond- ing value for a is a stable (unstable) fixed point for the best-response function ψ(·)—that is, iff its corresponding value for a satisfies the inequality |ψ′(a )| < . for τη > , if multiple equilbria arise then the iie is always unstable. on the contrary, in our simulations the lie is always stable. finally, the behavior of the hie is more complex. in particular, for the hie to be stable we require that private signals not be “too” precise when compared with the public signal. in the extreme case when τη = , we can formally analyze the best-response mapping and obtain the following result. corollary . suppose τη = . then (i) ψ ′(a ) < and (ii) the lie (resp., hie) is stable (resp., unstable) with respect to the best-response dynamics: |ψ′(a∗∗∗ )| > > |ψ ′(a∗ )| . ( ) intuitively, if private information is much more precise than public information then the retrospective inference and the variance reduction loop become very strong. in that case we approach a situation close to that described in corollary , which makes the hie always unstable. in figure we set β = , γ = / , and τu = τv = ; we also partition the parameter space {τε × τη | τη ∈{ , . , . . . , }, τε ∈{. , . , . . . , }} into five regions depending on whether multiple equilibria or instead a unique equilibrium obtains, whether the hie is stable, and whether responses to private information are strategic substitutes or strategic complements. this claim follows immediately from the inequality ψ( ) > ; hence the best-response mapping cuts the -degree line from below at the iie, which implies that ψ′(a∗∗ ) > . as shown in figure , the responses of traders to private information in the hie and the lie are strategic complements or substitutes depending on the parameters. for given τε, the higher is τη figure : the equilibrium set for β = , γ = / , τu = τv = , τη ∈{ , . , . . . , }, and τε ∈ {. , . , . . . , }. the black line denotes the set τη = τε. for values of (τε,β) in the white and yellow regions, the equilibrium is unique, whereas multiple equilibria (me) obtain when (τε,β) are in the other regions, where the hie can be stable or unstable depending on the difference between τη and τε. remark . what is the effect of a shock to parameter values on the market’s equilib- rium? the answer to this question depends on whether or not the hie is stable (see the online appendix). when the hie is stable we can easily generate non-monotonic effects of exogenous parameter changes (e.g., in private signal precision or in risk toler- ance) on the response to private information, the conditional volatility of returns, and the informational efficiency of prices. these results are possible because a parameter change may induce traders to coordinate at a different equilibrium. for instance, it is possible that a large decrease in private signal precision produces an increase in the equilibrium response to private information and informational efficiency—as well as a decline in the conditional volatility of returns, with the equilibrium shifting from the initial lie to the hie. when the hie is unstable, numerical simulations show that the effect of even a mild shock to parameter values depends on how persistent is the demand of liquidity traders. when β ∈ ( , ), the equilibrium converges to the lie; when β = , the market oscillates between two nonequilibrium values. the more likely it will be for at least one of the two equilibria to display strategic complementarities. for instance, when β = , γ = / , τu = τv = , τε = , and τη = . we obtain (a ∗ ,a ∗∗∗ ) = ( . , . ) and (ψ′(a∗ ),ψ ′(a∗∗∗ )) = (− . ,− . ). increasing τη to yields (a∗ ,a∗∗∗ ) = ( . , . ) and (ψ′(a∗ ),ψ ′(a∗∗∗ )) = (− . , . ). finally, if we further increase τη to (resp., to ), then the hie disappears and we obtain a∗ = . with ψ ′(a∗ ) = − . (resp., a∗ = . with ψ ′(a∗ ) = . ). e equilibrium strategies and limits of the beauty contest anal- ogy we characterize first investors’ strategies. corollary . at a linear equilibrium, the strategies of an informed investor are given by x (si,p ) = a αe (ei [v] −p ) + αp −αe αe e [θ ], ( ) x (si,sp ,p ,p ) = a αe (ei [v] −p ). ( ) in the event of multiple equilibria, if a =  a ∗ then αp < αe , (∂xi /∂p ) < , covi [v −p ,p −p ] < ; a∗∗ ,a ∗∗∗ then αp > αe , (∂xi /∂p ) > , covi [v −p ,p −p ] > . ( ) if β = then αp < αe , (∂xi /∂p ) < , and covi [v −p ,p −p ] < . according to ( ), in the second period an investor behaves as if he were in a static market. so in the first period this investor loads his position while anticipating the second- period price and scaling it down according to his uncertainty regarding p (see ( )). in this case, the investor’s strategy can be expressed as the sum of two components (see ( )). the first component captures the investor’s activity based on his private estimation of the difference between the fundamentals and the equilibrium price. such activity is akin to “long-term” speculative trading that aims to take advantage of the investor’s superior information on the asset’s liquidation value (since p is correlated with v). the second component captures the investor’s activity based on the extraction of public information (i.e., order flow). this trading instead aims to time the market by exploiting short-run movements in the asset price related to the evolution of aggregate demand. along the hie, the price is closer to fundamentals. as a result, when observing e [θ ] = a (v −e [v]) + θ > the investor infers that this realization is mainly driven by fundamentals information; he therefore goes long in the asset, “chasing the trend”. this behavior reflects his anticipa- tion that second-period investors will bid the price up when he unwinds his position, as implied by the sign of covi [v−p ,p −p ]. along the “keynesian” lie, prices are driven more by liquidity trading and so the trader acts instead as a “contrarian” investor. this observation also suggests that the aggregate trading behavior of informed in- vestors differs across the two equilibria. in the lie, investors trade less aggressively on private information and thus exploit more aggressively the predictability of liquidity traders’ demand. the opposite occurs in the hie, where aggregate demand is driven by trading that is relatively more informed. we can demonstrate these claims formally by evaluating informed investors’ first-period aggregate position ∫ x (si,p ) di = x (v,p ), x (v,p ) = a αe (ē [v] −p ) + αp −αe αe e [θ ], ( ) and then computing the following covariances: cov [ a αe (ē [v] −p ),θ ] = − ( a τ + αp αe τv τ τu ) < ( a) cov [ αp −αe αe e [θ ],θ ] = αp −αe αe τv τ τu   < lie> hie ( b) the aggregate long-term speculative position is always negatively correlated with the noise shock (see ( a)). for the short-term aggregate position, this correlation is observed only in the lie (see ( b)). in other words, for a given noise shock realization, investors in the hie speculate against it according to the long-term component of their strategy while apparently trading along with it according to the short-term component. the intuition is that, along the hie, investors trade so aggressively on their private information that they more than offset the initial price deviation from fundamentals generated by θ . for example, if θ > then investors short the stock so aggressively that its price undershoots the fundamentals. in equilibrium, then, investors find it profitable to purchase shares based on order flow information. along the lie, investors trade less aggressively on private information and so the covariances of both the long- and short-term components of investors’ demand with liquidity traders’ demand have concordant signs. remark . it is interesting that, along the hie, the asset is a giffen good in the second period (see ( )). differentiating xi with respect to p , we can break down the effect of we can prove that ( a) is larger (in absolute value) at the hie than at the lie when τη = , and our numerical simulations indicate that this difference holds also when τη > . a price increase into a substitution effect and an “information” effect: ∂x (si,sp ,p ,p ) ∂p = a αe   ∂ei [v]∂p ︸︷︷︸ information effect − ︸︷︷︸ substitution effect   . ( ) along the hie, investors rely strongly on prices, which are extremely informative about liquidation value. in this case, the substitution effect is swamped by the information effect. along the lie, the opposite happens and the asset is a normal good in the second period. giffen goods often arise when the learning from uninformed investors prevails, in which case the aggregate information effect dominates the substitution effect (see, e.g., barlevy and veronesi ( ), yuan ( ), vives ( )). this could happen also in the presence of feedback effects when prices are informative both about the fundamentals and about the likelihood of coordination among informed investors, since the feedback effect would then strengthen the information effect (as in ozdenoren and yuan ( )). our last result in this section relates the two equilibria to the reliance of price on public information. corollary . suppose τη > . . let β ∈ ( , ], and assume there are multiple equilibria. in that case, if a =  a ∗ then αp < αe and cov[p ,v] < cov[ē [v],v], a∗∗∗ then αp > αe and cov[p ,v] > cov[ē [v],v]. . if β = , then αp < αe and cov[p ,v] < cov[ē [v],v]. if liquidity trading is persistent then, along the hie, investors escalate their response to private information. in this case the extra weight added to ᾱe (see ( )) is large enough to draw the price closer to fundamentals (than is the consensus), in contrast with allen, morris, and shin ( ). in view of the results obtained in section iii.d, this equilibrium is stable provided that private information is not too much more precise than see admati ( ) and cespa ( ) for discussions about the existence of giffen assets due to information effects in the context of a multi-asset ree model. to see this, observe that ∂xi /∂p = (a /αe )(∆a τu/λ τi − ) = −γτi /( + γ∆a τu). along the hie (resp., lie), as shown in proposition , +γ∆a τu < (resp., +γ∆a τu > ). these inequalities prove the result. the exogenous public signal. along the lie, the price is farther away from fundamentals compared to consensus. this equilibrium, which shares the same properties of the one found by allen, morris, and shin ( ), is always stable. remark . according to numerical result and corollary , the inventory component of liquidity is larger in the lie than in the hie. that difference suggests an alternative interpretation of corollary : when prices are farther away from (resp., closer to) fun- damentals as compared with the consensus, inventory risk is high (resp., low). from an empirical standpoint, the implication is that the inventory component of liquidity is in- creasing in the extent of the difference between how accurately fundamentals are assessed by asset prices versus the consensus. f robustness in this section we perform some robustness exercises. first, we extend our model to encompass the possibility that residual uncertainty affects the asset payoff. second, we show that a very similar pattern of equilibrium multiplicity arises in a model with long-term traders who face residual uncertainty about the final payoff. (our analysis of both these extensions is given in the online appendix.) finally, we discuss the effect of extending the number of trading rounds and allowing investors to receive more than one private signal. f. the effect of residual uncertainty assume that investors face residual uncertainty over the final liquidation value. that final payoff is written as v̂ = v + δ, where δ ∼ n( ,τ− δ ) is a random term orthogonal to all random variables in the market and about which no investor is informed. our inclusion of the random term δ allows one to study the effect of an increase in the residual uncertainty that characterizes the investing environment in periods of heightened turbulence. it is intuitive that, when investors face residual uncertainty, they put less weight on their own signals because prices and private information are less useful in predicting the asset payoff. this dynamic is likely to weaken the retrospective inference and variance reduction loop and may even eliminate the hie. yet our analysis shows that, in general, residual uncertainty neither eliminates the hie nor makes it unstable. even when there is residual uncertainty, the expressions for prices and investors’ strategies do not change (i.e., the expressions ( ), ( ), and ( ) still hold). however, the equilibrium obtains as the solution of a system of two highly nonlinear equations and is therefore more difficult to solve. numerical analysis establishes that: (i) an equilibrium akin to the lie always arises; (ii) for low values of /τδ there can be as many as five equilibria, and at least one of these will be a hie; (iii) if residual uncertainty is high then a unique equilibrium obtains and only lie-type equilibria survive. in our baseline simulation, we set τv = and find that, for τδ < , the hie vanishes. although at first blush a small level of residual uncertainty (e.g., σ δ ≤ / ) may seem to cast doubt on the hie’s relevance, it is possible to show that this parameterization is in line with calibrated asset pricing models. for instance, wang ( ) models the asset payoff as a dividend process ft+ = ρft + ωt+ , where ft is a persistent component and ωt+ an orthogonal random error term that corresponds to our residual uncertainty term. here the coefficient ρ parameterizes the effect of past fundamentals on current ones. in this framework, the fraction of variance coming from residual uncertainty is − ρ (i.e., the ratio of σ ω to the steady-state variance of ft+ or σ ω/( − ρ )), which in our framework corresponds to σ δ/(σ δ + σ v). it is easy to show that, for ρ ∈ (. , . ), residual uncertainty in the dynamic model is of comparable importance to that implied by the parameter τδ = . so if, for example, we take our model to represent trading patterns that occur at a quarterly frequency, then the previous statement implies (roughly) a critical value of ρ = . at a yearly frequency; that value is commonly used for calibration in asset pricing models. f. long-term investors consider again the market with residual uncertainty, but now suppose that investors have a long horizon and so maximize the expected utility of their final wealth. for simplicity we will address the case in which the public signal is useless (τη = ). we find that multiple equilibria are possible in this scenario as well, and the reasons are similar to those given for the case of short-term investors. a long-term investor in the first period speculates on short-term returns and takes into account the hedging possibilities of second-period trading. the equilibrium strategy of investor i in the first period is actually a linear combination of (ei [p ]−p ) and ei [xi ] (cespa and vives ( )). if traders do not expect prices to change, then their optimal period- position would be just as in a static market. the risk of holding such a position we are indebted to an anonymous referee for suggesting this calibration exercise. this strategy is of the form xi = Γ (ei [p ] − p ) + Γ ei [xi ], where Γ and Γ are equilibrium parameters and ei [xi ] = Λ − ( −λ ∆a )(ei [v] − p̂ ). would be due only to the liquidation value’s unpredictability. however, if a change in prices is expected then traders optimally exploit short-run price differences. two factors increase the risk of their period- position: the partial unpredictability of the price change; and the impossibility of determining their exact future position. nevertheless, the opportunity to trade again in the future does serve as a hedge against potentially adverse price movements. in equilibrium, this option reduces risk and thereby—in the absence of residual uncertainty—exactly offsets the price risk conditional on private information. so when there is no residual uncertainty, traders’ strategies incorporate static responses to private information and there is a unique equilibrium. in this case, the optimal strategy of an informed trader is static (i.e., buy and hold): in the first period, informed traders receive their private signal and take a position; in the second period, there is no informed trading. although investors may nonetheless speculate on price differences, they do so only for market-making purposes (i.e., to profit from the mean reversion of liquidity trading). when there is residual uncertainty, investors in the second period scale down their trading activity as the final payoff becomes harder to forecast. this weakens the hedging effect of the re-trading opportunity and renders strategies truly dynamic, leading investors to speculate on short- term price movements based on their private information. these consequences reinforce the retrospective inference and variance reduction loop and lead to multiple equilibria, since the market’s liquidity in the second period strongly affects a trader’s reaction to private information in the first period. in summary, with long-term and risk-averse investors there may be multiple equilibria when there is either residual uncertainty (he and wang ( ), cespa and vives ( )) or a common shock to private signals (grundy and mcnichols ( )). we may have situations then with a negative price impact in the second period. this arises because in those cases informed traders have incentives to use their private information to speculate on short-term price movements and long-term traders may behave as short-term ones. if the asset price is not expected to change in response to today’s information, then the market is not expected to receive any new private information and so the model collapses to one in which traders hold the risky asset for two periods. in that case, those positions naturally coincide with the ones they would hold in a static market. indeed, a long-term trader who faces uncertain impending liquidation will find his private signal to be of little use in period . as a result, such a trader will behave in the first period more like a short-term trader: he will try to unwind his first-period holdings in the market at time and thus carry little of that inventory to the liquidation date. f. more private signals, more trading rounds the model can be extended to encompass the possibility that investors trade for more than two periods and/or receive additional private signals during each round of trading. however, the analysis becomes more complicated without any effect on the qualitative re- sults. in particular, we can still show that multiple equilibria (with the stated properties) arise provided β > . iv asset pricing implications in this section we investigate the asset pricing implications of our analysis. first, we show that liquidity trading persistence can generate positive autocovariance of returns irrespec- tive of whether beliefs are heterogeneous (as in banerjee, kaniel, and kremer ( )) or whether investors’ preferences exhibit a behavioral bias (as in daniel, hirshleifer, and sub- rahmanyam ( )). second, we look at the expected volume of informational trading and then compare the model’s predicitons with predictions under “differences of opinion” models. third, we discuss identification problems in models with multiple equilibria and derive a set of empirical implications that allow one to distinguish the hie from the lie. finally, we show how our model can provide a narrative of some episodes related to the recent financial crisis. a return autocovariance we start by computing the return autocovariance at different horizons. corollary . suppose τη > . at equilibrium, the following statements hold. (i) for all β ∈ [ , ], cov[p −p ,p − v̄] < . (ii) for β ∈ ( , ], cov[v −p ,p − v̄] < ; for β = , cov[v −p ,p − v̄] = . (iii) for β ∈ ( , ], if there are multiple equilibria then—along the hie—we have cov[v− p ,p −p ] > . if β = , then cov[v −p ,p −p ] < . this result states that, along the hie, momentum always occurs at short horizons (i.e., near the end of the trading horizon) whereas the reversal of returns occurs at long horizons. numerical simulations in a three-period model show that, along the hie, both cov[v −p ,p −p ] and cov[p −p ,p −p ] are positive. parts (i) and (ii) of the corollary hold because a given estimated first-period imbalance e [θ ] has the opposite effect on p −v̄ as it does on both p −p and v−p . for part (iii), a covariance decomposition (and the normality of returns) yields: cov[v −p ,p −p ] = cov[e [v −p ],e [p −p ]] + cov [v −p ,p −p ] = βΛ vari [p ] γ var[e [θ ]] + ( + γτu∆a )(βa ∆a τu − τ ) + γτητuβa (γτi ) τ τu . ( ) the first term in this decomposition captures the covariation in forecasts of conditional returns, e [v−p ] and e [p −p ]—in other words, the covariance “explained” by p . the second term captures the conditional covariation of returns, the “residual” covariance. all else equal, if trading is persistent then the anticipated effect of the first-period imbalance on the second- and third-period expected returns is of the same sign; hence the first term is always positive when β > . suppose that investors in the first period estimate a selling pressure from liquidity traders. if p < p then the outcome p < v is more likely than is p ≥ v because liquidity traders’ sales of the asset are likely to persist in the second period. for the second term, factoring out the effect of first-period information suggests that the joint covariation of returns around their expectations could be driven either by liquidity trading or by fundamentals information. in the hie, prices are driven by informed traders; hence the second effect predominates and there is positive covariance of returns around their means. conversely, prices in the lie are more driven by liquidity trades and so returns tend to covary around their means in opposite directions. when τη = , all of the results obtained in corollary continue to hold. we can also prove that, for β sufficiently high, momentum occurs at short horizons also along the lie (numerical simulations confirm this result for the case τη > ). formally, we have the following statement. one can easily verify that cov[v−p ,p −v̄] = cov[e [v−p ],e [p −v̄]] = −βΛ cov[e [θ ],p ] < and cov[p −p ,p − v̄] = cov[e [p −p ],e [p − v̄]] = (βΛ − Λ ) cov[e [θ ],p ] < . suppose that e [θ ] < . then our pricing equation ( ) implies a reduction in p so that a risk- averse investor will be awarded higher expected returns, inducing her to absorb the shock. indeed, we have e [p − p ] = (βΛ − Λ )e [θ ] > . if β > then selling pressure is likely to persist, which implies that prices will be depressed again at date and will thus ensure positive expected returns: e [v −p ] = −βΛ e [θ ] > . in this way, the persistence of liquidity trades offsets the mean reversion effect resulting from the first period’s short-term investors’ unwinding at date . proposition shows that in this case +γτu∆a < , which by ( ) implies that cov [v−p ,p −p ] > . corollary . suppose τη = . then, along the lie, for τv < τ̂v there exists a value β̂ such that for all β > β̂, cov[v −p ,p −p ] > . (the expression for τ̂v is given in the appendix; see (a. ).) along the lie, momentum is a sign of strong liquidity trading persistence and is due to the effect of the covariance explained by p in ( ). this finding is consistent with prices in that equilibrium being driven by liquidity trades, so here the predictability of returns is a sign of poor informational efficiency. indeed, it is possible to show that, for β sufficiently large, momentum arises also in a model with no private information. along the hie, however, momentum occurs for any value of β ∈ ( , ]. this means that even though (a very mild) persistence is required, momentum in this case is not due to liquidity trading. to the contrary, the hie properties illustrated in proposition suggest that momentum here is rather a sign of rapid price convergence to the fundamentals. according to the “time series momentum” evidence, which spans a vast class of finan- cial instruments, the lagged -month excess return on a given asset is a good predictor of that same asset’s “one year ahead” return. in addition, moskowitz, ooi, and ped- ersen ( ) document the following patterns associated with time-series momentum: (i) hedgers (who in our setup can be proxied by liquidity traders) have stable positions for extended time periods and so induce a persistent price pressure, yielding continuation of returns; (ii) speculators benefit from time-series momentum by going long in an asset to exploit its anticipated price trend (at the expense of hedgers); (iii) the spot price of the asset underlying the futures reacts slowly to information. these patterns are con- sistent with behavior along the lie. indeed, along the lie, the covariance of the long- and short-term components of investors’ demand with liquidity traders’ demand has the same (negative) sign; see equations ( a) and ( b). the implication is that investors fully exploit the predictability of liquidity trades—while mildly offsetting their price im- pact with their information so that prices are driven by liquidity trades. under these conditions, it pays to exploit liquidity traders’ predictability precisely because so little of the information about fundamentals affects aggregate orders. b expected volume and return predictability we now address the implications of our results for the expected volume of informational trading. this claim can be demonstrated by computing limτε→ cov[v−p ,p −p ] = (β−γ τvτu)/γ τ uτ v, which implies that momentum in this case arises when β > γ τvτu. we start by computing the expected traded volume in the market with heterogeneous information net of the expected volume when there is no private information. we have v ≡ ∫ e[|x (si,p )|] di− ∫ e[|x (p )|] di = ∫ √ π var[x (si,p )] di− ∫ √ π var[x (p )] di = √ π (√ a τ − ε + τ − u − √ τ− u ) ( ) and v ≡ ∫ e[|x (si,p ,p ) −x (si,p )|] di− ∫ e[|x (p ,p ) −x (p )|] di = ∫ √ π var[ x (si,p ,p ) −x (si,p )] di− ∫ √ π var[ x (p ,p ) −x (p )] di = √ π (√ (a −a ) τ− ε + ( + (β − ) )τ− u − √ ( + (β − ) )τ− u ) . ( ) using v + v to measure the total volume of informational trading, we obtain the following result. corollary (expected volume of informational trading). suppose τη > . then, at equilibrium, for all β ∈ ( , ] the expected volume of informational trading is higher along the hie. when β = , only the equilibrium with a low volume of informational trading survives. proof. rearranging corollary ’s expressions for investor strategies yields xin = anεin − θn for n = , . for a normally distributed random variable y , we have e[|y |] = √ π var[y ]. since a∗∗∗ > a ∗ , it now follows from ( ) that v is larger along the hie. according to ( ), v + v is an increasing function of a for a > a , a condition that is satisfied along the hie. finally, by corollary , if β = then a∗ < a . the intuition for corollary is straightforward: because investors in the hie step up in a market with no private information, investors absorb only the orders of liquidity traders. in equilibrium, then, their positions reflect only liquidity traders’ demand and so e[|x |] = (( /π)τ− u ) / . this approach is taken by he and wang ( ), among others. their response to private signals, the position change due to private information is higher along such equilibrium. taken together, corollaries and imply that a high volume of informational trading in the second period predicts a continuation of returns regardless of how persistent liquidity trading is—a conclusion that accords with the evidence presented by llorente et al. ( ). yet a low volume of informational trading can also be associated with momentum as long as liquidity trading is persistent enough. however, momentum in this case signals slow price convergence to the liquidation value. in short, momentum is compatible with both a high volume and a low volume of informational trading, but the implications of continued returns for price informativeness are markedly different in the two situations. the extant literature typically associates volume realizations with investors’ diver- gence of opinions about the asset payoff (see, e.g, kandel and pearson ( )). in our setup, disagreement is measured as follows: disag = var [ ein[v] − ēn[v] ] = var[αenεi] = τε τ in . ( ) from this expression and proposition , we conclude that disagreement is low (high) along the hie (lie). this statement and corollary now imply the following. corollary . volume is high (resp., low) in the equilibrium with low (resp., high) levels of disagreement. this corollary accommodates recent empirical evidence on the relationship between the convergence of opinions and the trading volume around earnings announcements. indeed, giannini, irvine, and shu ( ) find that large volume is actually compatible with convergence of opinions—a result that runs counter to what most of the literature on transaction volume implies. their finding can be explained as follows. from expressions ( ) and ( ) it is clear that volume is increasing in a /τε. we now use ( ) and obtain a τε = ( γ λ ∆a vari [p ] ) var[αe εi]. ( ) the first component on the right-hand side of equation ( ) captures the effect of in- vestors’ perceived risk on volume; the second term coincides with our definition of dis- agreement. along the hie (lie), we know that disagreement is low (high) but we also know that investors face little (considerable) risk concerning the price at which their po- sitions unwind. the latter effect prevails in our setup, which implies that high trading volume is a good proxy for low disagreement and low perceived risk. our model predicts in addition that, when volume is high and opinions are converging, prices should serve as a reliable signal of the underlying fundamentals. finally, our findings on volume are also related to banerjee ( ) and kondor ( ). the former paper compares differences of opinion (do) models to rational expectations (re) models. one prediction is that in a do model, differently from a re one, the conditional volatility of returns is negatively related to expected volume. that relation is precisely the one found in our re setup with strategic complementarities (a coupling of corollary and numerical result ) even though investors agree on a common prior. hence we conclude that observing a negative correlation between trading volume and the conditional volatility of returns is insufficient grounds for rejecting a re model. on the contrary, this correlation may well indicate that the retrospective inference mechanism described in our model is responsible for the observed regularity. kondor ( ) stud- ies a two-period trading model with three-factor fundamentals and short-term traders who have factor-specific information. in his model, a public signal on the fundamentals generates disagreement because it leads traders to compare their factor-specific private information to the public signal and thereby gauge the magnitude of the factor about which they have no private information. the author shows that an increase in the infor- mativeness of public signals can, by facilitating disagreement, generate large volume as well as prices that are not only more informative but also more volatile (conditional on the public signal). our model can produce similar patterns for price volatility. however, in our setup the association between a burst in trades and higher price volatility results from a public signal that is precise enough to stabilize the hie. c stock price fragility according to greenwood and thesmar ( ), a fragile asset is one that is vulnerable to non-fundamental demand shocks. these authors find that ownership concentration increases asset fragility but also that the active trades of hedge funds and mutual funds can mitigate fragility by counteracting the effect of mutual funds’ flow-induced trades. for example, set τu = τv = , τε = , τη = . , γ = / , and β = ; then we obtain two stable equilibria, a∗ = . and a ∗∗∗ = . . by corollary , volume is higher along the hie. furthermore, calculating price volatility yields var[p ] ∗∗∗ = . and var[p |sp ]∗∗∗ = . , as compared with var[p ]∗ = . and var[p |sp ]∗ = . . thus, price volatility is larger in the hie compared to the lie in the first (resp. second) period. the idea is that if the mispricing induced by non-fundamental demand shocks becomes large enough, then hedge funds will step in to correct it by taking offsetting positions. along the hie, this hypothesis is in line with the mechanism outlined in ( a) and ( b). greenwood and thesmar ( ) find that the distribution of offsetting trades is extremely heterogeneous across stocks, with some stocks characterized by strong offsetting effects and with other stocks for which this effect is relatively weak. our analysis implies that the former stocks should be those for which the hie is likely to prevail and hence should be associated with the combination of high trading volume and converging opinions. conversely, we predict that stocks associated with low volume and diverging opinions should be more fragile. d identifying equilibria we know from jovanovic ( ) that models governed by multiple equilibria of structural parameters have severe identification problems and also that “the set of distributions on observable outcomes that are consistent with a given structure can be quite large.” pos- itive identification results are obtained in a range of papers that use simple models with multiple equilibria (e.g., discrete entry or binary games; see the accounts in ackerberg et al. ( ) and berry and tamer ( )). identification of structural parameters is achieved through equilibrium refinements, shape restrictions, informational assumptions, or the specification of equilibrium selection mechanisms. alternatively, inference can be based on the identified features of the models with multiple equilibria, which are sets of values of the structural parameter vector (see, e.g., ciliberto and tamer ( ) and the refinement in henry and galichon ( )). in the model developed here, with two stable equilibria there is no equilibrium re- finement or equilibrium selection mechanism to be used. given the presence of strategic complementarities in our model, a promising approach is the one of echenique and ko- munjer ( ) based on monotone comparative statics (mcs) results. unfortunately, the type of multiplicity that arises in our paper fails to satisfy mcs, which this literature requires for identification (see the online appendix). equilibria can nonetheless be identified based on their respective implications for spe- cific market observables. according to proposition , the inference component of the spread is negative along the hie and positive along the lie. at the same time, by nu- merical result and corollaries and we know that, in the hie, the conditional volatility of returns is low, trading volume is high, and these patterns occur with low disagreement. finally, corollary implies that in the hie there is mild positive autocor- relation of returns at short horizons. more insights on identifying the specific features of each equilibrium can be obtained by contrasting the qualitative properties of the hie and lie via numerical simulations. in what follows we assume that τv = . , τu = . , τε = , γ = / , τη = . , and β = / . with these values, a stable hie obtains ({a∗ ,a∗∗∗ } = { . , . } with {ψ′(a∗ ),ψ ′(a∗∗∗ )} = {− . ,− . }) and we obtain momentum along the lie and in the unique equilibrium with no private information (τε = ); see table . next we set v̄ = and extract , i.i.d. normal shocks for v, u , u , and η and then average across the prices and shocks. the results of this exercise are presented in figure , where we plot the positions of liquidity traders at dates and followed by the simulated price paths along the low-information equilibrium, the high-information equilibrium, and the equilibrium with no private information. lie hie equilibrium with τε = cov[v −p ,p −p ] . . . × cov [v −p ,p −p ] − . . − , cov[z ,p −p ] − . − . × − − . × e [v −p ] − . − . − , e [p −p ] − . − . × − − , table : autocovariance of returns (unconditional and conditional), return predictability from order flows, and expected returns from liquidity provision in the numerical example. panel (a) in the figure displays the position of liquidity traders, which in this simula- tion is (on average) positive at both dates. according to panel (b), if there is no private information then prices mirror liquidity traders’ demand. indeed, since short-term traders are risk averse, they require compensation—for satisfying the positive demand of liquidity traders—that is proportional to their perceived uncertainty about the payoff. that com- the green line in panels (b), (c), and (d) of the figure is the (log of the) average of the semi-strong efficient prices obtained in the simulations—that is, ln(( / ) ∑ j= enj[v]), n = , . the horizontal line in the plots for the price paths is the (log of the) average value of the fundamentals (in this simulation, ln( . ) ≈ . ). n . . . . . Θn (a) n log@en @vdd log@ pn d (b) n log@en @vdd log@ pn d (c) n . . . . log@en @vdd log@ pn d (d) figure : liquidity traders’ demand (panel (a)) and the path of prices (red) and semi- strong efficient prices (green) along the equilibrium with no private information, the lie, and the hie (respectively, panels (b), (c), and (d)). parameter values are as follows: v̄ = , τv = . , τu = . , τε = , γ = / , τη = . , and β = / . pensation drives p above v̄ in this equilibrium. in panel (c) of figure we see that prices display a qualitatively similar behavior along the lie. yet because traders are informed, an > and so part of liquidity traders’ shock is accommodated by offsetting speculative orders (in this numerical example, sell orders). these orders transmit information and thereby diminish investors’ perceived uncertainty about the payoff, which implies that the price adjustment needed to accommodate θn is lower than in the τε = case. in the lie, then, absent private information the price path reflects the liquidity traders’ position and is therefore hump-shaped. along the hie (panel (d)), in contrast, the first-period price coincides almost exactly with the semi-strong efficient price and with the full-information value. in this equilibrium, traders aggressively speculate (sell) against the liquidity (buy) shock θn based on their private information. this behavior drives p below v̄ and close to v, accelerating price adjustment. these trades are highly informative and thus dra- matically reduce investors’ perceived uncertainty about the payoff, which explains why the price nearly matches en[v] even though the market’s risk-bearing capacity is limited (γ < ∞). in this equilibrium, short-term trading offsets the impact of liquidity traders’ orders on prices, and the price path is inversely hump-shaped. these different patterns complement our findings and suggest that (i) the compensa- tion investors receive for supplying liquidity should be greater in the lie than in the hie and (ii) the short-term predictability of prices based on order flow information (z ) should be higher along the lie than along the hie. both predictions are confirmed by the last three rows of table . the latter prediction is also consistent with the evidence pre- sented by chordia, roll, and subrahmanyam ( ), who find that short-horizon return predictability from order flows declines when the market is more liquid. combining these observations with proposition and our previous results in sec- tion iv suggests a way to identify the hie and the lie from the data. our model predicts that the lie arises for extreme values of public signal precision (which could be proxied, e.g., by the number of analysts following a given security). this equilibrium is characterized by (i) a positive inference component of the price impact, (ii) momentum or reversal depending on the strength of trading persistence, (iii) high expected returns from liquidity provision, (iv) prices that are far from the semi-strong efficient price, (v) high short-horizon return predictability from order imbalances, and (vi) low volume accom- panied by high levels of disagreement. our model predicts that the hie may arise for intermediate values of public signal precision. this equilibrium is characterized by (i) a negative inference component of the price impact, (ii) mild momentum, (iii) low expected returns from liquidity provision, (iv) prices that are close to the semi-strong efficient price, (v) low short-horizon return predictability from order imbalances, and (vi) high volume accompanied by low levels of disagreement. see table , which summarizes the model’s empirical implications. the equilibrium predictions of table help us when using market data to distin- guish among equilibria and also when seeking to discriminate among different behavioral theories. the main implications of our findings can be listed as follows. . high volume associated with informative prices and low disagreement argues for the hie in relation not only to the lie but also to alternative theories based on differences of opinion and in which disagreement is associated with high volume. in the expected returns from liquidity provision are calculated per unit of expected demand from liquidity traders, e [θ ] = . since e [v − p ] = −βΛ e [θ ] and e [p − p ] = (βΛ − Λ )e [θ ], it follows that expected returns are due only to the inventory component of liquidity—consistently with our interpretation. β = β ∈ ( , ] lie hie reliance on public information high high low liquidity low low high price impact (period ) { + + − strong strong weak price informativeness low low high risky asset (period ) normal normal giffen expected volume of informational trading low low high return correlation at long horizons − − − return correlation at short horizons − ± + disagreement high high low conditional volatility high high low table : the beauty contest revisited. fact, an observation of high trading volume with high levels of disagreement would be inconsistent with our model at either the lie or the hie. . a negative covariance between conditional volatility and volume need not disqualify re models (as suggested by banerjee ( ), for example) because that finding is consistent with our results. . a negative inference component of the price impact identifies the hie and the oc- currence of return reversals at short horizons identifies the lie, with the maintained hypothesis that our model holds. . if for fragile (non-fragile) stocks—in the sense of greenwood and thesmar ( )— there is a low (high) volume transacted when there is high (low) disagreement, then that would constitute evidence for our lie (hie). in other words, fragility should be associated with low trade volume and divergence of opinions. e meltdowns finally, our model can also shed some light on episodes of sudden liquidity dry-ups as exemplified in severe form by the recent financial crisis. we offer an information-based explanation that complements the standard one given in terms of insufficient arbitrage capital. the quant meltdown of august . in the second week of august , several hedge funds started unwinding their holdings (arguably for non-informational reasons). khandani and lo ( ) show that the price impact of trades spiked during the event. their conclusion is that a lack of arbitrage capital (together with the increased importance of high-frequency trading for market making) was largely responsible for the meltdown. in our model, a large increase in price impact is consistent with an increase in the volume or volatility of liquidity trading and a switch from the hie to the lie (since then the hie may disappear; see figure (d)). in fact, the lie prevails also when the demand of liquidity traders becomes larger and more volatile. in that case, the retro- spective inference and variance reduction loop weakens and the high-liquidity equilibrium disappears. the alternative view is that even if capital had been abundant (with cara utilities there is no room for endowment effects), a similar meltdown could have occurred if informational conditions were like those that we find. the financial crisis and public information. several authors have argued that, during the – crisis, the selling pressure of investors drove asset values downward and below the fundamentals (though this was followed by a rebound; cella, ellul, and giannetti ( )). a possible reason for the occurence of such large corrections is the lack of (or “slow moving”) arbitrage capital (duffie ( )), which exhausted the risk- bearing capacity of liquidity suppliers. our theory provides an alternative explanation based on the absence of informational conditions that would have allowed for a milder correction. in particular, the dearth of reliable public information (proxied here by a steep reduction in τη) may have reduced the market’s risk-bearing capacity, relegating most of the economy to the lie. as argued in the online appendix, if the market coordinates at a hie that poor public information has rendered unstable, then an additional mild shock to public information leads this market to the lie. indirect evidence of such a transition is that “contrarian” liquidity providing strategies were extremely profitable during the for instance, gorton and metrick ( ) report that repo depositors during the crisis “did not know which securitized banks were most likely to fail.” financial crisis (as documented by nagel ( ))—in line with our prediction of the lie derived in section iv.d. with regard thereto our paper makes the additional prediction that, in the cross section, the assets that underwent the most extreme corrections were those for which the public information was poorest. v conclusions in this paper we argue that the persistence in liquidity traders’ positions has a significant effect on the response of risk-averse, short-term investors to their private signals. when the orders of liquidity traders are correlated across trading dates, investors reassess the evidence (about the fundamentals) obtained at the early trading stage based on the new information gathered in the market. such “retrospective” inference can generate strategic complementarities in the use of private information that in turn can yield multiple stable equilibria, and these equilibria can be ranked in terms of price informativeness, liquidity, and volatility. our analysis reveals that, if uninformed orders are predictable, then the effect of investors’ short horizons on market observables depends on the quality of public infor- mation. when public information is not much more precise than private signals, the retrospective inference channel is not too strong; in this case, a stable equilibrium arises that is characterized by low volatility, high liquidity, high price informativeness, high volume, and low levels of disagreement. this equilibrium exists alongside another equi- librium in which prices are more volatile and less informationally efficient, the market is thinner, volume is low, and disagreement is high. when public information is either very precise or very poor, the low-volatility equilibrium disappears or becomes unstable while the high-volatility equilibrium survives. thus our analysis indicates that there could be a nonlinear effect of public information on market observables. furthermore, our results can guide the empirical literature investigating the effect of investors’ horizons on market patterns as a means of identifying the stock characteristics associated with the high- or low-volatility equilibrium. our paper also clarifies the role of higher-order expectations in asset pricing. with liquidity trading persistence, prices are driven by average expectations about fundamen- tals and about liquidity trading. this dynamic, in contrast to the beauty contest results of allen, morris, and shin ( ), can draw prices either systematically farther away from nagel ( ) finds that the stocks of small, illiquid, and highly volatile companies generated the largest contrarian returns during the financial crisis. or closer to fundamentals—along the lie and the hie, respectively—as compared with the consensus of investors. we show that when public information is either very precise (compared with private signals) or very poor, prices are farther away from fundamentals compared to consensus. however, a public signal of intermediate precision makes the hie stable, thereby drawing prices closer (than consensus) to the fundamentals. we also link the hie and lie to the magnitude of the inventory component of liquidity, to the price impact, and to the returns from liquidity supply. thus, our analysis establishes the limits of the beauty contest analogy for financial markets and provides empirical implications to assess the effect of hoes on asset prices. table summarizes the empirical implications of our model. we provide the observ- ables that can discriminate among equilibria (under our model’s hypothesis) and among behavioral theories as well. high trading volume associated with low conditonal volatil- ity and low disagreement discriminates in favor of our hie against not only the lie but also alternative, do theories wherein disagreement is associated with high volume. furthermore, a negative covariance between conditional volatility and volume does not preclude the validity of rational expectations models because it is consistent with our model. we find also that fragility (in the sense of greenwood and thesmar ( )) should be associated with low transacted volume and divergence of opinions. in addition, our paper provides an alternative interpretation for empirically documented regularities in the patterns of return autocorrelation. the literature has only recently begun to in- vestigate the relationship between empirical regularities, such as the momentum effect, and the role of hoes in asset prices (see, e.g., verardo ( )). our paper 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(a. b) rearranging (a. ) we obtain p = αp a (a v −βa v + βa v + θ ) + ( −αp )e [v] =  αp a + ( −αp ) ∆a τuτ ︸︷︷︸ λ  z + τητi sp + γτ e [v] + βz γτi = λ z + τη τi sp + βαp a z + ( −αp ) τ τ e [v], (a. ) which provides an alternative expression for p which separates the impact on second period “news” from the information contained in the first period price and the public signal. in the first period owing to cara and normality, an agent i trades according to x (si,z ) = γ ei [p ] −p vari [p ] , (a. ) where, using (a. ), ei [p ] = ( λ ∆a + τη τi ) ei [v] + γτ e [v] + βz γτi , (a. ) vari [p ] = ( λ ∆a + τη τi ) τi + λ τu + τη τ i . (a. ) replacing (a. ) and (a. ) in (a. ) yields x (si,z ) = γ (λ ∆a + τη/τi )ei [v] vari [p ] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) − γ vari [p ] p = a si + a τ τε e [v] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) − γ vari [p ] p , where a = γ (λ ∆a + τη/τi )αe (λ ∆a + τη/τi ) /τi + λ /τu + τη/τ i . (a. ) imposing market clearing: x + θ = , which implies a v + θ + a τ τε e [v] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) = γ vari [p ] p . finally, solving for the equilibrium price and collecting terms yields p = a ( vari [p ] γ + βαp a ) ︸︷︷︸ αp ( v + θ a ) + ( −αp )e [v]. (a. ) proof of corollary in the second period, rearranging (a. ), p = e [v] + Λ e [θ ], where Λ = vari [v]/γ. in the first period, from (a. ) we have αp = a ( vari [p ] γ + β vari [v] γ ) . by definition of the inventory component obtained in ( ), Λ = αp /a . this implies Λ = vari [p ] γ + β vari [v] γ . proof of corollary for the second period price, see (a. ). for the first period price, we rearrange (a. ) to obtain p =  αp a + ( −αp )a τuτ ︸︷︷︸ λ  z + ( −αp )τvτ v̄. (a. ) proof of proposition to prove existence it suffices to note that in the first period, the equilibrium responsiveness to private information is defined by the fixed points of the following function ψ(a ) = γ (λ ∆a + τη/τi )αe (λ ∆a + τη/τi ) /τi + λ /τu + τη/τ i . (a. ) by inspection φ(a ) ≡ a −ψ(a ) = is a quintic in a , and therefore always possesses a real root. note that at equilibrium a > , otherwise λ ∆a > , which in view of (a. ) yields a contradiction. suppose that β > . to prove multiplicity we proceed as follows. note that φ( ) = −γ τετu(a + γ(τη + a τu))(τε + τη + a τu + τv) < (a. a) φ(a ) > . (a. b) therefore, there exists an equilibrium a∗ ∈ ( ,a ). next, evaluating φ(·) at a = + γτua γβτu , yields φ ( + γτua γβτu ) > , while evaluating it at a = + γτua γβτu , yields φ ( + γτua γβτu ) < , provided β > (a. a) γ τετu > ( β − ) − β (a. b) τη ≤ τ̂η ≡ ( / β − / )γa τ u + / a τu(β − / ) + γa τu( / −β) . (a. c) therefore, provided (a. a), (a. b), and (a. c) are satisfied, a second equilibrium a∗∗ exists in the interval ( + γτua γβτu , + γτua γβτu ) . given that φ(·) is a quintic, it must have an odd number of roots, which implies that when (a. a), (a. b), and (a. c) are satisfied at least another equilibrium a∗∗∗ must exist in the interval ( + γτua γβτu ,∞ ) . given the location of the roots we can conclude that < a∗ < a < a ∗∗ < a ∗∗∗ . further- more, we have + γτu∆a =   > for a = a ∗ < for a ∈{a∗∗ ,a∗∗∗ } which implies that λ∗ > , while λ ∗∗ < , and λ ∗∗∗ < . finally, we prove that price informativeness increases across the three equilibria. for τ this is immediate, since it increases in a . for τ as one can verify, given that a ∗ < a < a ∗∗ we have τ ∗ < τ ∗∗ . furthermore, for a > ( + γτua )/(γβτu), ∂τ ∂a > , which implies τ∗∗ < τ ∗∗∗ . suppose now that β = . then, φ(·) becomes a cubic in a : φ(a ) = a τu(( + γa τu) + γ τuτν) −a γ a τ u(a τu + τε + τν) (a. ) + a ( a τu(a ( + γa τu) + γτν) + τv(( + γa τu) + γ τντv) + τε + γ τu(τν + a τu) ) −γ a τu(a τu + τε + τν)(τv + a τu + τε + τν), with a negative discriminant. this implies that with β = there exists a unique equilib- rium in linear strategies with first period responsiveness a∗ . to locate the equilibrium, note that φ ( γ a τu(a τu + τε + τν) + γ τu(a τu + τε + τν) ) = − γ a τντu(a τu + τε + τν) + γ τu(a τu + τε + τν) < (a. a) φ(a ) = a (τv + τε( + γ τu(τν + τε( + γa τu) + τv))) > . (a. b) therefore, a∗ ∈ ( γ a τu(a τu + τε + τν) + γ τu(a τu + τε + τν) ,a ) . furthermore, since ψ′(a ) ∝ a τu(γ a τu(a τu + τε + τν) −a ( + γ τu(a τu + τε + τν)), we also have that for β = , the weights to private information in the first period are strategic substitutes. proof of corollary for any β ∈ [ , ], in the second period an equilibrium must satisfy a = γτε. in the first period, assuming τη = , and using (a. ), at equilibrium a equilibrium must satisfy φ (a ) ≡ a λ (τ + τε) −γτε∆a τu = a ( + γτu∆a ) −γ τε∆a τu = . (a. ) the above equation is a quadratic in a which for any a > and β > possesses two positive, real solutions: a∗ = + γτua ( + β) − √ ( + γτua ( + β)) − β(γτua ) βγτu (a. ) a∗∗ = + γτua ( + β) + √ ( + γτua ( + β)) − β(γτua ) βγτu , (a. ) with a∗∗ > a ∗ . this proves that for β > there are two linear equilibria. inspection of the above expressions for a shows that βa ∗ < a , while βa ∗∗ > a . the result for λ , var [p ] follows from substituting (a. ) and (a. ), respectively in λ and var [p ]. to see that prices are more informative along the hie note that in the first period var[v|z ]− = τ = τv + a τu. in the second period, the price along the hie is more informative than along the lie if and only if ( + β + γa τu(( −β ) + β( + β ))) √ ( + γa τu( + β)) − β(γa τu) γ β τu > , which is always true. given that τi = τ + τε, this also implies that Λ ∗∗∗ < Λ ∗ . finally, substitution of (a. ) and (a. ) in vari [p ] shows that vari [p ] ∗∗∗ < vari [p ] ∗. in view of ( ) this implies that Λ∗∗∗ < Λ ∗ . when β → , along the hie we have lim β→ + γτu(a + βγτε) + √ + γτu( (a + βγτε) + γτu(a −βγτε) ) βγτu = ∞, while along the lie, using l’hospital’s rule, lim β→ + γτu(a + βγτε) − √ + γτu( (a + βγτε) + γτu(a −βγτε) ) βγτu = γa τu + γa τu . from (a. ) it then follows that in this case αp < αe . finally, defining a∗ = γa τu + γa τu , and taking the limit of λ as β → when a = a∗ yields lim β→ λ∗ = + γτua γ(τv + (a ∗ ) τu + a τu + τε) > , whereas limβ→ λ ∗∗∗ = . proof of corollary starting from the lie, we need to verify that |ψ′(a∗ )| < , or that when a = a∗ , γβa τu < ( + γτu∆a ) . substituting (a. ) on r.h.s. of the above inequality and rearranging yields |ψ′(a∗ )| < ⇐⇒ − ( + a γτu( −β))( + a γτu( −β) + √ ( + γτua ( + β)) − β(γτua ) ) < , which is always satisfied. for the hie, we need instead to verify that |ψ′(a∗∗∗ )| > , or that when a = a ∗∗∗ , γβa τu > ( + γτu∆a ) . substituting (a. ) on r.h.s. of the above inequality and rearranging yields |ψ′(a∗∗∗ )| > ⇐⇒ ( + a γτu( −β))(−( + a γτu( −β)) + √ ( + γτua ( + β)) − β(γτua ) ) > , which is always satisfied, since the first factor in the product on the r.h.s. of the above expression is positive, while manipulating the second factor shows that √ ( + γτua ( + β)) − β(γτua ) > ( + a γτu( −β)) ⇐⇒ a βγτu > . proof of corollary in the second period, the result follows from the fact that since at equilibrium a = γτε, a αe = γ vari [v] . in period we have x (si,z ) = γ (λ ∆a + τη/τi )ei [v] vari [p ] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) − γ vari [p ] p . adding and subtracting (a /αe )p from the right hand side of the above expression yields x (si,z ) = a αe (ei [v] −p ) + ( a αe − γ vari [p ] ) p + γ vari [p ] ( β γτi z + τ τi e [v] ) . the second and third terms in the above expression can be rewritten to obtain( a αe − γ vari [p ] ) p + γ vari [p ] ( β γτi z + τ τi e [v] ) = β( −αp ) −γτ αp a τi vari [p ] e [θ ] = αp −αe αe e [θ ]. note, also, that setting ρ ≡ a /a , we can express αp = αe ( + (βρ− )τ τi ) . (a. ) this implies that for a = a ∗ , αp < αe , whereas the opposite holds for a ∈{a∗∗ ,a∗∗∗ }. to differentiate xi with respect to p , we first express the information contained in a trader’s forecast in terms of p . to this end we use (a. ) and write z = λ ( p − τη τi sp − βαp a z − ( −αp ) τ τ e [v] ) . substituting the above in ei [v], and differentiating xi with respect to p yields ∂xi ∂p = − γτi + γτu∆a . for a = a ∗ , we know that ∆a > , so that the information effect reinforces the substi- tution effect and the asset is a normal good. conversely, when multiple equilibria arise, for a ∈{a∗∗ ,a∗∗∗ }, + γτu∆a < , implying that the asset is a giffen good. finally, to compute the conditional covariance we have covi [v −p ,p −p ] = covi [v −p ,p ] = covi [v,p ] − vari [p ]. (a. ) using ( b), we obtain covi [v,p ] = τi ( λ ∆a + τη τi ) . on the other hand, from (a. ) we have vari [p ] = τi ( λ ∆a + τη τi ) + λ τu + τη τ i . substituting these expressions in (a. ) and rearranging yields covi [v −p ,p −p ] = − γτi τi ( λ (τi − τη) τu + ∆a τη τi ) . according to proposition , when a ∈ {a∗∗ ,a∗∗∗ }, ∆a < and λ < . therefore, covi [v −p ,p −p ] > . conversely, along the lie, the opposite occurs. proof of corollary we have already established in corollary that along the hie (lie) αp > αe (αp < αe ). now, using ( ) the covariance between p and v is given by cov[v,p ] = αp τv + ( −αp ) ( τv − τ ) , (a. ) and carrying out a similar computation for the first period consensus opinion cov [ ē [v],v ] = αe τv + ( −αe ) ( τv − τ ) . (a. ) we can now subtract (a. ) from (a. ) and obtain cov [ p − ē [v],v ] = αp −αe τ , (a. ) implying that the price at time over relies on public information (compared to the optimal statistical weight) if and only if the covariance between the price and the funda- mentals falls short of that between the consensus opinion and the fundamentals. proof of corollary to compute cov[p −p ,p − v̄] we first note that cov[p −p ,p − v̄] = cov[p ,p ] − var[p ]. (a. ) next, cov[p ,p ] = cov[e [p ],e [p ]] + cov [p ,p ] = cov[e [p ],p ]. computing cov[e [p ],p ] = var[e [v]] + (Λ + βΛ )cov[e [v],e [θ ]] + βΛ Λ var[e [θ ]] = a τ τ τv + (Λ + βΛ ) a τ + βΛ Λ τv τ τu , and var[p ] = a τu τ τv + Λ τv τ τu + Λ a τ . substituting these expressions in (a. ) and rearranging yields cov[p −p ,p − v̄] = − vari [p ] γ ( Λ τv τ τu + a τ ) < . consider now cov[v −p ,p − v̄], decomposing the covariance yields cov[v −p ,p − v̄] = cov[e [v −p ],p ] + cov [v −p ,p − v̄]︸︷︷︸ = = −βΛ (cov[e [θ ],e [v]] + Λ var[e [θ ]]) = −βΛ ( a τ + Λ τv τ τu ) = −βΛ λ τu , which is always negative for β ∈ ( , ], and null for β = . finally, to compute cov[v − p ,p −p ] we decompose again the covariance cov[v −p ,p −p ] = cov[e [v −p ],e [p −p ]] + cov [v −p ,p −p ]. computing, e [v −p ] = −βΛ e [θ ], and e [p −p ] = (βΛ − Λ )e [θ ]. therefore, cov[e [v −p ],e [p −p ]] = βΛ vari [p ] γ var[e [θ ]]. (a. ) next, we obtain cov [v −p ,p −p ] = ( + γτu∆a )(βa ∆a τu − τ ) + γτητuβa (γτi ) τ τu . (a. ) when a ∈ {a∗∗ ,a∗∗∗ }, ∆a < −(γτu)− , and the above expression is always positive, which implies that along the hie cov[v −p ,p −p ] > . proof of corollary to prove this result, we impose τη = in (a. ) and (a. ), obtaining cov[v −p ,p −p ] = − λ γτi τu ( −β∆a τi − τv a τi ) . (a. ) looking at (a. ) we again verify that along the hie there is momentum. this is true because in that equilibrium λ < and ∆a < . along the lie momentum can occur, depending on the persistence of liquidity trades. to see this, note that since in this equilibrium λ > and ∆a > , from (a. ) momentum needs −β∆a τi − τv a τi < , which can be rearranged as an (implicit) condition on the magnitude of β: a τi ∆a (τi − τv) < β < . if β = , the above condition is never satisfied. indeed, in this case there exists a unique equilibrium in which ∆a = a > . therefore, when β = returns always display reversal. if β = , the condition is satisfied if a τv + a (τε + a τu) < ∆a τu(τε + a τu). isolating τv in the above expression yields: τv < τ̂v ≡ (∆a −a )(τε + a τu) a , (a. ) which, since a does not depend on τv (see (a. )), gives an explicit upper bound on τv. hence, if τv < τ̂v, there exists a β̂ such that for all β ≥ β̂, when τη = , momentum occurs between the second and third period returns along the lie. b online appendix b. non-monotone comparative statics and dynamic adjust- ment what is the effect of a shock to parameters’ values on the equilibrium of the market? the answer to this question depends on whether the hie is stable or not. starting from the case in which the hie is stable, figure in the paper (panel (b)) implies that a decrease in private signal precision or in risk tolerance can have a non- monotone effect on a and thus on the conditional volatility of returns, and informational efficiency of prices. to see this, consider first the case of private signal precision. suppose that τv = τu = , τε = . , γ = / , τη = , and β = . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and correspond to the intersection of the orange best response function with the -degree line in figure (panel (a)). suppose the market coordinates on the lie. suppose now that the precision of the private signal decreases to τε = . the new best response is depicted by the dashed curve in the figure. again we have three equilibria with the lie and hie given respectively by a ∗,new = . , and a ∗∗∗,new = . . which equilibrium does the market coordinate on? with adaptive dynamics, we can see that this will be the hie. thus, in this case a decrease in private signal precision determines an increase in the response to private information and informational efficiency, and a decrease in the conditional volatility of returns (along the initial lie, var [p ] = . , while along the new hie, var [p ] = . ). non-monotonicity requires however a sufficiently large reduction in private precision. indeed, in panel (b) we repeat the same exercise, assuming that τε is lowered to . in this case, adaptive dynamics implies that the new equilibrium along the dashed best response is the lie. panel (c) and (d) show that similar effects arise with a reduction in risk tolerance. consider now the case in which the hie is unstable. in this situation numerical simulations show that starting from the hie, the effect of a shock (even a very mild one) to parameters’ values depends on the persistence of liquidity traders’ demand. in detail: in both cases the hie is stable case since (∂ψ/∂a )|a =a∗∗∗ = −. , and (∂ψ/∂a )|a =a∗∗∗,new = . . denoting respectively by ψ and ψnew the orange and dashed best responses, non monotonicity requires that that ψ(a∗ ) > ψ new (a ∗∗,new ). if the reduction in private precision is such that ψ(a ∗ ) > ψnew (a ∗∗∗,new ), the new equilibrium along the dashed best response is still the hie, but monotonicity is restored since a ∗∗∗,new < a ∗ . a Ψha l ΤΕ = ΤΕ = . (a) a Ψha l ΤΕ = ΤΕ = . (b) a Ψha l Γ= � Γ= � (c) a Ψha l Γ= � Γ= � (d) figure : adjustment to a shock when the hie is stable. we plot the best response ( ) for τv = τu = , γ = / , τη = , β = , and τε = . (orange). in panel (a) and (b) we analyze the effect of a reduction in the precision of the private signal to τε = (dashed best response, panel (a)) and τε = (dashed best response, panel (b)). in panel (c) and (d) we analyze the effect of a reduction in risk tolerance to γ = / (dashed best response, panel (c)) and γ = / (dashed best response, panel (d)). when β ∈ ( , ), the equilibrium converges to the lie; when β = , the market oscillates between two non-equilibrium values. in figure , panel (a) we plot the best response for τv = τu = , τε = , γ = / , τη = / , and β = . . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ ′(a∗∗∗ ) = − . . as shown in the figure, perturbing the hie an iterated application of the best response leads the market to coordinate on the lie. consider now panel (b) where we plot the best response for τv = τu = , τε = , γ = / , τη = / , and β = . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ ′(a∗∗∗ ) = − . . in this case, iterating the application of the best response perturbing the hie (after about iterations) leads the market to oscillate between the non-equilibrium values . and . . thus, the implication is that, provided β < , if the market is at the hie a small shock to parameter values leads it to the lie. a yha l (a) a yha l (b) figure : adjustment to a shock when the hie is unstable. in panel (a) we plot the best response ( ) for τv = τu = , τε = , γ = / , τη = / , and β = . . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ′(a∗∗∗ ) = − . . in panel (b) we plot the best response ( ) for τv = τu = , τε = , γ = / , τη = / , and β = . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ ′(a∗∗∗ ) = − . . b. the effect of residual uncertainty in this section we perform a robustness exercise and assume that investors face residual uncertainty over the final liquidation value. therefore, we model the final payoff as v̂ = v + δ, where δ ∼ n( ,τ− δ ) is a random term orthogonal to all the random variables in the market, and about which no investor is informed. the addition of the random term δ allows to study the effect of an increase in the residual uncertainty that surrounds investors’ environment in periods of heightened turbulence, and shows that a price crash can occur within our framework. intuitively, when investors are faced with residual uncertainty, they put less weight on their signals, since prices and private information are less useful to predict the asset payoff. this is likely to weaken the retrospective inference and variance reduction loop, eliminating the hie. our analysis shows, however, that in general residual uncertainty does not eliminate the hie, nor makes it unstable. with residual uncertainty, the expressions for prices and investors’ strategies do not change (that is, expressions ( ), ( ), and ( ) in the paper hold). however, the equi- librium obtains as the solution of a system of the following highly non-linear equations: a = fa (a ,a ) ≡ γτε + κ (b. a) a = fa (a ,a ) ≡ γ τi (∆a ( + κ + γτu∆a ) + γτη)τετu (∆a ( + γτu∆a + κ) + γτη) τu + τi (( + γτu∆a + κ) + γ τητu) . (b. b) inspection of the cubic (b. a) shows that it possesses a unique real solution, which can therefore be substituted in (b. b) to solve the equilibrium as a fixed point of a best response in a , fa (a ,a (a )). in f figure we show the plot of such a best response mapping for the following parameterization: τu = τv = , τε = , τη = / , γ = , β = / , and τδ ∈ { , , , }. when τδ = , we have equilibria, only two of which are stable with respect to best response dynamics. furthermore, the equilibrium with a higher value of a displays a negative inference component of liquidity, as shown by the first row of table b. . this suggests that, when retrospective inference is not too strong, the presence of residual uncertainty per-se is not sufficient neither to make the hie disappear, nor to make it unstable. of course, as residual uncertainty increases, the strength of the loop weakens even more and the hie tends to disappear as shown by panels (b), (c), and (d) in the figure, where we plot the best response for τδ = , τδ = , and τδ = . table b. collects the results of our calculations for the different values of τδ. τδ {(a∗ ,ψ ′(a∗ )),a ∗ ,λ ∗ } {(a∗∗ ,ψ ′(a∗∗ )),a ∗∗ ,λ ∗∗ } {(a∗∗∗ ,ψ ′(a∗∗∗ )),a ∗∗∗ ,λ ∗∗∗ } {(a∗∗∗∗ ,ψ ′(a∗∗∗∗ )),a ∗∗∗∗ ,λ ∗∗∗∗ } {(a∗∗∗∗∗ ,ψ ′(a∗∗∗∗∗ )),a ∗∗∗∗∗ ,λ ∗∗∗∗∗ } {(. ,−. ), . , . } {( . , . ), . ,−. } {( . ,−. ), . ,−. } {( . , . ), . ,−. } {( . ,− . ), . ,−. } {(. ,−. ), . , . } {( . , . ), . ,−. } {( . , . ), . ,−. } {( . , . ), . ,−. } {( . ,− . ), . ,−. } {(. ,−. ), . , . } {( . , . ), . ,−. } {−−,−−} {−−,−−} {( . ,− . ), . ,−. } {(. ,−. ), . , . } {−−,−−} {−−,−−} {−−,−−} {−−,−−} table : equilibrium values and values of the derivative of the best response mapping at equilibrium for the plots of figure . a yha l (a) a yha l (b) a yha l (c) a yha l (d) figure : the best response mapping in the model with residual uncertainty. parameters’ values are τu = τv = , τε = , τη = / , γ = , and β = . when τδ ∈ { , }, five equilibria obtain, only two of which are stable (respectively, panel (b), and (a)). when τδ = , only the lie is stable (panel (c)). when τδ = , only the lie survives (panel (d)). in our baseline simulation, we set τv = , and find that for τδ < , the hie vanishes. while at first blush this small level of residual uncertainty may seem to question the relevance of the hie, it possible to show that this parameterization is not uncommon in calibrated asset pricing pricing models. for instance, wang ( ) models the asset payoff as a dividend process ft+ = ρft + ωt+ , where ft is a persistent component, and ωt+ an orthogonal random error term, which corresponds to our residual uncertainty term. the coefficient ρ in this case parameterizes the impact of past fundamentals on current ones. the fraction of variance coming from residual uncertainty in this framework is −ρ (that is, the ratio between σ ω and the steady-state variance of ft+ , which is σ ω/( −ρ )), which in our framework corresponds to τ− δ /(τ − δ + τ − v ). it is easy to show that with a value of ρ ∈ (. , . ), residual uncertainty in the dynamic model has a comparable importance as the one implied by the parameter τδ = . thus, if for example we take our model to represent trading patterns that occur at a quarterly frequency, this roughly implies a critical value of ρ = . at a yearly frequency, which is not uncommon as a calibration in asset pricing models. b. long-term investors consider the market with residual uncertainty but assume that now investors have a long horizon and maximize the expected utility of final wealth. for simplicity we will deal with the case where the public signal is useless (τη = ). in this case multiple equilibria are also possible and the reasons are similar to those of the case with short-term investors. a long-term investor in the first period speculates on short-term returns and takes into account the hedging possibilities of second period trading. the equilibrium strategy of investor i in the first period is in fact a linear combination of (ei [p ]−p ) and ei [xi ] (cespa and vives ( )). were traders not to expect a change in prices, then their optimal period position would be like the one of a static market, and the risk of holding such a position would only be due to the unpredictability of the liquidation value. if a change in prices is expected, traders optimally exploit short-run price differences. two factors add to the risk of their period position, as traders suffer from the partial unpre- dictability of the price change, and from the impossibility of determining exactly their future position. however, the opportunity to trade again in the future also grants a hedge against potentially adverse price movements. this, in equilibrium, yields a risk-reduction which when there is no residual uncertainty exactly offsets the price risk conditional on private information. as a consequence, with no residual uncertainty, traders’ strategies we are indebted to an anonymous referee for suggesting this calibration exercise. it is of the form xi = Γ (ei [p ]−p ) + Γ ei [xi ] where Γ and Γ are equilibrium parameters and ei [xi ] = Λ − ( −λ ∆a )(ei [v] − p̂ ). intuitively, if given today’s information the asset price is not expected to change, no new private information is expected to arrive to the market and the model collapses to one in which traders hold for two periods the risky asset. their position, then, naturally coincides with the one they would hold in a static market. have a static nature in their response to private information. still investors may spec- ulate on price differences but only for market making purposes to profit from the mean reversion of liquidity trading. with residual uncertainty strategies are truly dynamic and informed investors speculate on short-term price movements based on their private information. we have that in equilibrium the responsiveness to private information (when informed traders do not receive a new signal in the second period as in our base model, see cespa and vives ( )) is given by: a = γτε( + γτu∆a ) + κ + γτu∆a , a = γτε + κ . when κ = then a = a = γτε. with long-term investors, and under the assumptions of the model, the feed-back loop that generates multiplicity is broken because the optimal strategy of an informed trader is static (buy-and-hold): in the first period informed traders receive their private signal, take a position and then in the second period there is no informed trading, the informed traders just make the market absorbing the demands of liquidity traders. when κ > , a = ργτε/( + κ) with ρ > at any equilibrium. the endogenous parameter ρ captures the deviation from the long term private signal responsiveness due to the presence of residual uncertainty. thus, prior to the last trading round, investors react to their private signals more aggressively than if the liquidation value were to be realized in the next period. indeed, while residual uncertainty makes investors less confident about their signals, the presence of an additional trading round increases the opportunities to adjust suboptimal positions prior to liquidation. this, in turn, boosts investors’ reaction to private information. residual uncertainty implies that informed investors speculate on short-term price movements based on their private information. this makes possible multiple equilibria. indeed, faced with uncertain impending liquidation a long-term trader in period is not going to use much his private signal. this makes the trader behave in in fact, when β = we have that xi = e[xi |si,p ]. when β < traders speculate also on price changes based on public information. if informed traders were to receive a second signal in the second period then there would be informed trading in this period but still the strategies would be static and price impact would still be positive. the reason is that the trading intensity in the second period will always be larger than the one in the first period, a = γ (τε + τε ) > a = γτε, because private information about the liquidation value accumulates over time. with long-term traders we can not have negative price impacts when the joint information of traders reveals the liquidation value. the first period more like a short-term trader since he will try to unwind his first period holdings in the market at time , and carry little of that inventory to the liquidation date. in this case the liquidity of the second period market becomes much more important to determine the trader’s reaction to private information in the first period and multiple self- fulfilling expectational loops are possible as in the case with short-term traders. again the possibility of multiple equilibria is linked to having a negative price impact in the second period (λ < ) due to a large response to private information in the first period (generating ∆a < ). for example, three equilibra arise with τδ = ,τε = τv = τu = γ = and β = . and only in the low a equilibrium we have ∆a > and stability. in general three equilibria are obtained for high β and high τδ. multiple equilibria may arise also when there is a common shock in the private signal (grundy and mcnichols ( )). in summary, with long-term risk averse investors and either residual uncertainty (he and wang ( ), and cespa and vives ( )), or a common shock in the private signals (grundy and mcnichols ( )) there may be multiple equilibria. we may have situations then with a negative price impact in the second period. this arises because in those cases informed traders have incentives to use their private information to speculate on short-term price movements and long-term traders may behave as short-term ones. appendix online appendix non-monotone comparative statics and dynamic adjustment the effect of residual uncertainty long-term investors [pdf] the interplay of beauty, goodness, and usability in interactive products | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /s hci _ corpus id: the interplay of beauty, goodness, and usability in interactive products @article{hassenzahl theio, title={the interplay of beauty, goodness, and usability in interactive products}, author={m. hassenzahl}, journal={human–computer interaction}, year={ }, volume={ }, pages={ - } } m. hassenzahl published psychology, computer science human–computer interaction two studies considered the interplay between user-perceived usability (i.e., pragmatic attributes), hedonic attributes (e.g., stimulation, identification), goodness (i.e., satisfaction), and beauty of different mp -player skins. as long as beauty and goodness stress the subjective valuation of a product, both were related to each other. however, the nature of goodness and beauty was found to differ. goodness depended on both perceived usability and hedonic attributes. especially after using… expand view on taylor & francis researchgate.net save to library create alert cite launch research feed share this paper citationshighly influential citations background citations methods citations results citations view all topics from this paper usability human–computer interaction skin (computing) social cognition interactivity value (ethics) computer marc blank citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency the interplay between usability and aesthetics: more evidence for the "what is usable is beautiful" notion kai-christoph hamborg, julia hülsmann, k. kaspar psychology, computer science adv. hum. comput. interact. pdf save alert research feed is beautiful really usable? toward understanding the relation between usability, aesthetics, and affect in hci alexandre n. tuch, s. roth, kasper hornbæk, k. opwis, javier a. bargas-avila psychology, computer science comput. hum. behav. highly influenced pdf view excerpts, cites results and background save alert research feed aesthetics, usefulness and performance in user--search-engine interaction. adi katz computer science pdf view excerpt, cites background save alert research feed modelling user experience with web sites: usability, hedonic value, beauty and goodness p. schaik, jonathan ling computer science interact. comput. highly influenced pdf view excerpts, cites background, methods and results save alert research feed towards a theory of user judgment of aesthetics and user interface quality jan hartmann, a. sutcliffe, a. d. angeli computer science tchi highly influenced pdf view excerpts, cites methods, results and background save alert research feed beautiful, usable, and popular: good experience of interactive products for chinese users s. liu, x. zheng, guanmin liu, j. jian, k. peng psychology, computer science science china information sciences save alert research feed aesthetics, visual appeal, usability and user satisfaction: what do the user's eyes tell the user's brain? g. lindgaard engineering highly influenced pdf view excerpts, cites background save alert research feed aesthetics in interactive products: correlates and consequences of beauty m. hassenzahl psychology save alert research feed the influence of the search complexity and the familiarity with the website on the subjective appraisal of aesthetics, mental effort and usability a. chevalier, a. maury, n. fouquereau psychology, computer science behav. inf. technol. view excerpts, cites background, results and methods save alert research feed exploring the boundary conditions of the effect of aesthetics on perceived usability. john grishin psychology highly influenced view excerpts, cites background save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency the effect of perceived hedonic quality on product appealingness m. hassenzahl computer science int. j. hum. comput. interact. pdf view excerpts, references methods and background save alert research feed what is beautiful is usable n. tractinsky, a. katz, d. ikar psychology, computer science interact. comput. , highly influential pdf view excerpts, references methods, background and results save alert research feed assessing dimensions of perceived visual aesthetics of web sites tali lavie, n. tractinsky psychology, computer science int. j. hum. comput. stud. , pdf view excerpt save alert research feed what is beautiful is good, but…: a meta-analytic review of research on the physical attractiveness stereotype. a. eagly, r. d. ashmore, m. g. makhijani, l. longo psychology , pdf save alert research feed the thing and i: understanding the relationship between user and product m. hassenzahl psychology, computer science funology pdf view excerpts, references background save alert research feed effects of hedonic components and user's gender on the acceptance of screen-based information services n. mundorf, s. westin, nikhilesh dholakia psychology, computer science behav. inf. technol. save alert research feed apparent usability vs. inherent usability: experimental analysis on the determinants of the apparent usability m. kurosu, k. kashimura computer science chi ' highly influential view excerpts, references background and methods save alert research feed hedonic and ergonomic quality aspects determine a software's appeal marc hassenzahl, axel platz, michael burmester, katrin lehner computer science chi pdf view excerpt, references methods save alert research feed aesthetics and preferences of web pages b. schenkman, fredrik u. jönsson computer science behav. inf. technol. pdf view excerpts, references background save alert research feed extrinsic and intrinsic motivation to use computers in the workplace richard, p., bagozzi, paul, r. warshaw , save alert research feed ... ... related papers abstract topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue /home/www/ftp/data/hep-ex/dir_ / .dvi latest measurements of beauty quark production at hera v. chiochia adesy]desy - deutsches elektronen-synchrotron, notkestrasse , hamburg, germany a[ the latest results of beauty quark production measurements at hera are presented. new measurements have been obtained both in the photoproduction and the deep inelastic scattering regimes. the results were compared with the nlo qcd calculations. . introduction production of heavy quarks is a fascinating tool to understand the nucleon structure as well as the underlying qcd parton dynamics. in addition production of b quarks is a source of background for many searches for new physics at existing and future colliders. the high b mass (mb � Λqcd) should provide a solid basis for a perturbative calculation. nevertheless, so far discrepancies between the experimental cross section measure- ments and the nlo qcd calculation have been found. the experimental procedure often relies on the measurement of the transverse momentum prelt of the muon produced in the semi-leptonic decay with respect to the axis of the closest jet. this spectrum is harder for b quarks than for c quarks and, therefore, allows a statistical separation of the signal from the background. additional infor- mation such as lifetime measurements provided by silicon detectors can also be used. an alterna- tive tag is given by the coincidence of d∗ mesons and muons which provide sensitivity to the re- gion of low transverse b quark momenta and is less affected by background. the recent experimental results obtained at the hera collider are reviewed in both the photo- production (q ∼ gev ) and the deep in- elastic scattering (dis: q > gev ) kinematic regimes. . open beauty in photoproduction when the exchanged photon has small virtual- ity (q ) the time-scale of the interaction is such that its hadronic structure can be revealed. pho- toproduction at hera can therefore be similar to the processes at hadron colliders and supplies complementary information. both zeus and h already published results on b photoproduction [ – ]. the zeus experiment has now measured the differential cross sections of beauty photopro- duction using events with at least two jets and a muon in the final state [ ]. the luminosity used is almost three times larger than in the previous measurements. the fraction of events from b de- cays has been extracted using the prelt method. the kinematic region is defined by q < gev , . < y < . , pjet ( )t > ( ) gev, |ηjet ( )| < . , pµt > . gev and − . < ηµ < . . fig- ure shows a comparison between the measured differential cross section and a nlo qcd calcu- lation for different regions of the muon pseudora- pidity. the qcd prediction was calculated using the program fmnr [ ]. the hadronization is mod- eled by a peterson function and the spectrum of the semi-leptonic muon momentum was extracted from pythia [ ]. the bands around the nlo pre- diction show the results obtained by varying the b quark mass as well as the renormalization and factorization scales. the measured cross sections are a factor . larger than the central nlo pre- diction but compatible with it within the experi- mental and theoretical uncertainties. in addition, a dijet cross section (ep → bbx → jet jet x) has been determined using pythia to extrapolate to the unmeasured part η = − ln(tan θ/ ) is the pseudorapidity, where θ is the polar angle measured with respect to the proton beam direction. zeus - . - - . . . ηµ d σ /d η µ (p b ) dσ  dηµ (ep→bb – →e jj µ x) q < gev . , gev |ηj|< . pt pt µ> . gev zeus (prel.) - nlo qcd x hadr. nlo qcd figure . differential cross section of beauty pho- toproduction as a function of the muon pseudo- rapidity compared with nlo qcd calculations. of the muon kinematics and to correct for the branching ratio. for this measurement a different data sample has been used with looser cuts on the transverse momentum of the muon at large pseu- dorapidities. the result is σdijet = ± ± pb while the nlo qcd prediction is + − pb, corresponding to a data excess of a factor of two. . open beauty in dis first results in the dis region have been already released by the h collaboration [ ]. thanks to the high luminosity in the new zeus measurement [ ] differential distributions have been measured for the first time in dis. events were selected by requiring the presence of at least one muon in the final state and at least one jet in the breit frame . a total visible cross sec- tion of σvis = . ± . + . − . pb was measured for the reaction ep → ebbx → e jet µ x in the kinematic region defined by: q > gev , in the breit frame, defined by ~γ + x ~p = ~ , where ~γ is the momentum of the exchanged photon, x is th bjorken scaling variable and ~p is the proton momentum, a purely space-like photon and a proton collide head-on. . < y < . , pµ > gev, ◦ < θµ < ◦ and one jet in the breit frame with ebreitt > gev and − < ηlab < . . also for this measure- ment the prelt method was applied. this result has been compared with a nlo qcd calculation im- plemented in the hvqdis program [ ], after fold- ing the b quark momentum spectrum with a pe- terson fragmentation function and subsequently with a spectrum of the semi-leptonic muon mo- mentum extracted from rapgap [ ]. the nlo qcd prediction is . + . − . pb which agrees with the measured value within the errors. the differ- ential cross section as a function of q compared to the nlo calculation is shown in fig. . the - - - zeus q (gev ) d σ /d q ( p b /g e v ) zeus (prel.) - nlo qcd (hvqdis) . < mb < . gev / (q + mb ) < µ < (q + mb ) σ(e+p → e+ bb - x → e+ µ± jet x) . < y < . pµ > gev, o < θµ < o e t,jet breit > gev, - < η jet lab < . figure . differential beauty cross section as a function of q compared with the nlo qcd cal- culations. prediction of the monte carlo program cascade [ ], which implements a calculation based on the ccfm evolution equations [ ] and uses a kt - dependent gluon density, is pb which is in very good agreement with the measurement. in addi- tion, the simulation gives a good description of the measured differential cross sections. . d∗ − µ correlations the separation of charm and beauty contri- butions to the signal can also be performed by exploiting the charge and angle correlations of the d∗ meson and of the muon in the reaction ep → ebbx → ed∗µx. of particular interest is the configuration in which the muon and the d∗ originate from the same parent b-meson yielding unlike charge sign d∗ − µ pairs produced in the same hemisphere. using this strategy and performing a likeli- hood fit on the kinematic distributions h has extracted the cross sections of beauty and charm production in the kinematic region defined by pd ∗ t > . gev, |ηd ∗| < . , pµt > gev, |ηµ| < . and . < y < . [ ]. the measured values, which confirm previous results, are respectively σbvis = ± ± pb and σcvis = ± ± pb which are well above lo+parton shower monte carlo expectations. a similar analysis has been conducted by zeus [ ] whose selection has been optimized for decays of b quarks. the beauty cross section, measured in a slighty different phase space (pd ∗ t > . gev, |ηd∗| < . , pµt > . gev, − . < ηµ < . ), is σbvis = ± + − pb. the result is in good agreement with the the h measurement once the same cuts are applied. in order to compare the measured cross section with nlo qcd pre- dictions a photoproduction-enriched sample has been selected by applying the cuts q < gev and . < y < . . furthermore, the mea- surement is restricted in a b quark rapidity range ζb < where the distributions of the monte carlo program used to extrapolate agree with the re- spective fmnr spectra within ± %. the result for the extrapolated cross section is σ γp→b(b)x = . ± . + . − . nb while the nlo prediction of fmnr for this reaction is only . + . − . nb. . conclusions and outlook the understanding of the b quark production mechanism is an outstanding puzzle in qcd. a set of new visible cross sections of beauty pro- duction, defined close to the detector acceptance, have been measured at hera. the results are about a factor . higher than the nlo qcd predictions but consistent within the experimen- tal and theoretical uncertainties both in the pho- toproduction and the dis regions. an excess of measured cross sections over the nlo qcd pre- diction is observed when attempts are made to extrapolate cross sections to regions which are not directly measured by the detectors. the hera collider is now starting a new phase of operation at higher luminosities. together with the enhanced b-tagging capabilities of the new h and zeus vertex detector and track- ing triggers more precise and differential measure- ments can be expected within the next five years. acknowledgments i would like to thank my collegues of the h and zeus collaborations for their work and their sug- gestions to this talk. references . c. adloff et al. [h collaboration], phys. lett. b ( ) [erratum-ibid. b ( ) ]. . h coll., contrib. paper no. / to ichep , osaka . j. breitweg et al. [zeus collaboration], eur. phys. j. c ( ) . . zeus coll., contrib. paper no. . . s. frixione, m. l. mangano, p. nason and g. ridolfi, phys. lett. b ( ) . . t. sjostrand, comput. phys. commun. ( ) ; e. norrbin and t. sjostrand, eur. phys. j. c ( ) . . h coll., contrib. paper no. . . zeus coll., contrib. paper no. . . b. w. harris and j. smith, phys. rev. d ( ) . . h. jung, comput. phys. commun. ( ) . . h. jung and g. p. salam, eur. phys. j. c ( ) ; h. jung, comput. phys. com- mun. ( ) . . m. ciafaloni, nucl. phys. b ( ) ; s. catani, f. fiorani and g. marchesini, phys. lett. b ( ) ; g. marchesini, nucl. phys. b ( ) . . h coll., contrib. paper no. . . zeus coll., contrib. paper no. . beauty and the bets christopher hitchcock beauty and the bets abstract. in the sleeping beauty problem, beauty is uncertain whether the outcome of a certain coin toss was heads or tails. one argument suggests that her degree of belief in heads should be / , while a second suggests that it should be / . prima facie, the argument for / appears to be stronger. i offer a diachronic dutch book argument in favor of / . even for those who are not routinely persuaded by diachronic dutch book arguments, this one has some important morals. . the problem beauty is about to sleep for a long time. not one hundred years or anything like that: two days will suffice. during that time she will be awakened briefly, either once (on monday) or twice (on monday and tuesday). for definiteness, let us say that beauty goes to sleep at : a.m. (midnight) on monday morning, and sleeps until : a.m. wednesday morning; the awakening(s) will take place at noon on the appropriate day(s). the number of awakenings depends upon the toss of a fair coin: if the result is heads, she is awakened but once; if tails, twice. the nature of her sleep is such that she will not remember being awake. in particular, when she is awakened, she will not know whether it is monday or tuesday. upon awakening on monday, what should be her degree of belief in h , the proposition that the coin landed heads? this problem was first posed in print by adam elga (elga ), who attributes it to robert stalnaker. related problems are presented in au- mann et al. ( ) and piccione and rubinstein ( ). the problem is interesting, because it involves an unusual form of reasoning under un- certainty. beauty is uncertain, not merely about the outcome of the coin toss, but also about what day it is. in the language of possible worlds: beauty is uncertain, not merely about which world she is in, but about where she currently is within the world. if we wish to represent beauty’s degrees of belief formally, it will not suffice to use a probability measure over possible worlds. rather, we will need to use a probability measure over a space of what quine ( ) calls ‘centered worlds’, ordered pairs synthese : – , . © kluwer academic publishers. printed in the netherlands. christopher hitchcock consisting of possible worlds and (spatio-)temporal locations within those worlds. . the argument for / if we imagine this scenario repeated a great many times, we would expect approximately half the coin tosses to result in heads, and half to result in tails. for each toss that results in heads, beauty will experience one awakening; for each toss that results in tails, she will experience two awakenings. therefore, she will experience two awakenings in which the most recent toss was tails for every awakening in which the most recent toss was heads. that is, in a repeated sequence of two-day slumbers, the relative frequency of heads-awakenings will be one-third. since the heads- awakenings and tails-awakenings are qualitatively identical, her degree of belief in heads on a given awakening ought to be / . . the argument for / since beauty knows that the coin is fair, her prior probability for h is / . (we assume she obeys lewis’s ‘principal principle’ ( ).) she knows that she will be awakened from her sleep at least once. therefore, upon awakening, she has gained no new information. so her degree of belief in h should remain at / . . prima facie the case for / does not look very strong. long-run relative frequencies are reliable guides to single case probabilities only when the individual trials are independent. in the sleeping beauty problem, the ‘trials’ are the individual awakenings (not runs of the whole experiment). thus the trials are manifestly not independent: if the first awakening is a tails-awakening then the second awakening will also be a tails-awakening. by contrast, the case for / appears to rest on well-grounded principles of probabilistic reasoning. the rule of updating by conditionalization says that if one’s prior degree of belief in heads is p (h ), then, upon learning e, one should update one’s degree of belief to p (h |e). violation of this rule – at any rate, deliberate, pre-meditated violation of this rule – makes one susceptible to a diachronic dutch book, or ddb for short (teller ). it follows that if one has not learned anything, then one’s degrees beauty and the bets of belief should not change. the claim that beauty should not change her mind if she has learned nothing new is not supported merely by intuition: it follows from a very general principle about belief revision. a related rule governing probabilistic reasoning is the ‘reflection principle’ (van fraassen ): pt (h |p(t ′, h, r)) = r where pt is the agent’s degree of belief at time t, and p(t ′, h, r) is the proposition that one’s degree of belief in h at time t′ ≥ t will be r. the reflection principle can also be justified by a ddb. the reflection principle clearly supports the answer of / . for suppose that beauty’s degree of belief upon awakening will be / . this new degree of belief does not depend upon her learning anything that she does not already know sunday night (before going to sleep). so beauty knows full well that her degree of belief will be / , that is, she knows that p(t′, h, / ) is true where t ′ is monday at noon. but surely her degree of belief in h should be / before going to sleep – after all, the coin is known to be fair. so if / is the correct answer to our puzzle, beauty’s degree of belief at time t on sunday evening will be of the form pt (h |p(t ′, h, / )) = / , in violation of reflection. if awakening with a degree of belief in heads equal to / violates these principles, and these principles are supported by ddb arguments, then it ought to be possible to show directly that waking up with that degree of belief renders beauty susceptible to a ddb. and indeed, this appears to be the case. before going to sleep, the bookie sells to beauty bet # on h ; the bet pays $ if the result of the coin toss is heads, nothing otherwise; and the bet costs $ . (i assume throughout that beauty’s utility is linear in dollars.) since beauty’s degree of belief in h before going to sleep is / , she will find this bet fair. upon awakening, her degree of belief in h is / (by hypothesis), so the bookie sells her bet # , on tails, with a payoff of $ , for a cost of $ . whatever the result of the coin toss, beauty will win one bet, for a payoff of $ , while paying out a total of $ for the privilege of gambling. this book of bets is shown in table i, where the entries in the ‘heads’ and ‘tails’ columns reflect beauty’s net gain or net loss on that outcome. a similar argument could be constructed for any degree of belief different from / . all in all, then, the case for / appears to be much stronger than the case for / . but the careful reader will have noted the frequent use of the word ‘appears’. we shall see in the sequel that there is an important flaw in the dutch book argument of the previous paragraph. but first, i present a further argument in favor of / . christopher hitchcock table i bets payoff cost heads tails bet # $ if heads $ $ −$ bet # $ if tails $ −$ $ combined $ $ −$ −$ . a symmetry argument for / elga ( ) offers a symmetry argument favoring the answer / . in this section i present a more formal argument for / that incorporates the same symmetry assumptions. this argument, i think, is highly suggestive, but not fully convincing. the argument is not fully convincing because several of the assumptions are difficult to construe, and thus hard to assess for plausibility. indeed, our difficulty in construing these assumptions will serve to underline just how puzzling the sleeping beauty problem really is. we begin by constructing a probability measure representing beauty’s degrees of belief. since beauty is uncertain not only about the state of the world that she is in, but also about her location within it, the probability function that represents her degrees of belief will have to be defined over sets of centered worlds. for purposes of solving our problem, it suffices that each centered world specify three things: whether the coin toss landed heads or tails; the day of the week; and whether beauty has just been awakened from a deep sleep. so we can let our elementary centered pro- positions be of the form 〈d, o, b〉, where d is the day of the week (sun or mon or . . . or sat), o is the outcome of the coin toss (h or t ), and b is beauty’s present status (just awakened, a, or other, ∼ a). thus, for ex- ample, the centered proposition 〈mon, h, a〉 asserts that today is monday, the coin lands heads, and beauty has just been awakened from a deep sleep. we will write disjunctions of these basic propositions in the natural way: 〈mon, h 〉 ≡ 〈mon, h, a〉 or 〈mon, h, ∼ a〉; h ≡ 〈sun, h 〉 or 〈mon, h 〉 or . . . or 〈sat, h 〉; and so on. what should beauty’s degrees of belief over these centered propos- itions look like? since she knows the coin toss to be fair, her ‘prior’ probability for h should be p (h ) = / . ‘prior’ means in the absence of any further information, before she has conditionalized on any other propositions. since this implies the absence of any temporal information, ‘timeless’ might be a better word than ‘prior’. since the outcome of the beauty and the bets coin toss is unaffected by the passage of time, her degrees of belief in the outcome of the coin toss should be independent of her degrees of belief regarding the day of the week. thus she should have p (〈h, mon〉) = p (〈t , mon〉), and likewise for the other days of the week. now what about beauty’s ‘priors’ of the form p (mon)? here the word ‘prior’ is even more suspect: immediately ‘prior’ to the start of a new week she should assign p (sat) = (assuming we adopt the religion- biased convention that the week starts on sunday). but clearly this is not what we have in mind. what we do have in mind is something more like this: suppose that beauty were to wake up after a very long sleep, having no idea how long she slept, nor indeed any idea what day it was when she went to sleep. then what would her degrees of belief be in the propositions sun, mon, etc? but even this suggests the conditional probabilities p (sun|a), p (mon|a), etc., rather than the unconditional probabilities p (sun), p (mon), etc. really, we just want beauty’s degrees of belief in the absence of any information about what day it is. and at this point, it is natural to appeal to symmetry: in the absence of any in- formation favoring one day of the week over the others, she should assign p (sun) = p (mon) = . . . = / . the reader will be excused for finding these probabilities ‘funny’; we shall see that their funniness makes it easier rather than harder to justify the symmetry assumption. finally, we want to give beauty conditional credences of the form p (a|mon&t ), reflecting her knowledge of the protocol that determines her schedule of awakenings. a natural assignment would be p (a|mon&t ) = p (a|mon&h ) = p (a|t ues&t ) = ; p (a|t ues&h ) = p (a|w ed&t ) = . . . = p (a|sun&h ) = . note that a represents awakening from a deep sleep of the sort she enters on monday at midnight. we assume that she sleeps normally the rest of the week, and that her normal awakenings are qualitatively distinguishable from her deep sleep awakenings. we might balk at the assignments p (a|mon&t ) = p (a|mon&h ) = p (a|t ues&t ) = ; after all, there are many times during those days when she has not just been awakened. very well then, let us have p (a|mon&t ) = p (a|mon&h ) = p (a|t ues&t ) = p, < p ≤ . the important thing is that these probabilities are greater than zero, and that they are equal. she will definitely be woken up on each of these scenarios, and she will be awake equally often and for an equal duration in each. nonetheless, there is still something ‘funny’ about all of these probabilities. although there is a positive probability of ∼ a occurring on tuesday (and on monday as well, if p < ), beauty can never learn of ∼ a’s being true in this scenario. put another way, a receives a probability of less than , but it is, to beauty, unfalsifiable. christopher hitchcock upon awakening, beauty conditionalizes upon a. using bayes’ theorem, beauty’s posterior probabilities can be computed from the probabilities specified above: p (mon&t |a) = p (mon&h |a) = p (t ues&t |a) = / . from this it follows that p (h |a) = / . beauty’s degree of belief upon wakening should be / . qed one way in which a ‘halfer’ might respond would be by challenging the independence assumption. he might reason as follows: suppose that upon awakening, beauty were told that it was monday rather than tuesday; wouldn’t that lead her to raise her degree of belief that the coin landed heads? in order to reflect the evidential relevance of the day for the out- come of the coin toss, beauty’s ‘priors’ should be such that mon and h are positively correlated. lewis ( ) offers an argument along these lines. in order to arrive at the answer / , however, it is not enough to simply reject the independence assumption: each day of the week would have to be evidentially relevant to h in just the right way. for example, if beauty’s ‘priors’ are p (mon&h ) = / , p (mon&t ) = / , p (t ues&h ) = / , p (t ues&t ) = / , then, upon learning that a, her posterior probability for h will be equal to / as desired. (this would also give us p (h |mon&a) = / , as suggested by lewis ( )). so far, so good. but now let us suppose that her probability is / for every other centered proposition of the form 〈d, o〉. then, adding over the all days, her total ‘prior’ probability for heads would be / �= / . in order for beauty’s ‘prior’ p (h ) to be / , she would also have to have p (d&h ) = / , p (d&t ) = / , for every other day of the week d. it is very hard to see how these degrees of belief could be independently motivated. indeed, it is easy to show that there is no probability distribution over the defined space that satisfies all of the following conditions: (i) p (h ) = / , (ii) p (h |a) = / , (iii) p (mon) = p (t ues), (iv) p (mon, t ) > , and (v) p (d, h ) = p (d|t ) for every d other than monday or tuesday. the first assumption is a constraint of the problem, and the second is the halfer’s desired answer; thus the halfer must reject one of (iii)–(v), and it is hard to see any non-ad hoc motivation for doing so. how did the halfer get into this mess? a fundamental mistake was made at the very first step. it is indeed true that if, upon awakening, beauty were told that it was monday rather than tuesday, that would lead her to raise her degree of belief that the coin landed heads. from this it follows that mon is evidentially relevant to h , given a. this relevance is reflected in the original probability measure constructed above: p (h |mon&a) = / > / = p (h |a). but it is a mistake to infer from this that mon is unconditionally relevant to h . , suppose, for example, that the nature of beauty’s sleep is such that she can still receive information and reason beauty and the bets probabilistically while sleeping. if she were given the information that it is monday while sleeping, this should not affect her subjective probability that the coin landed heads. if we accept the symmetry argument for / developed in this section, then we can explain what went wrong with the argument for / in section . that argument wrongly claims that beauty learns nothing new. in fact, beauty does ‘learn’ a, that she has just awakened from a deep sleep. the word ‘learn’ is in scare quotes, because what beauty ‘learns’ is not an ordinary proposition, but rather a centered proposition. let w be the proposition that beauty (tenselessly) awakes from a deep sleep. that is, w is the proposition that is true of every world in which beauty awakes from a deep sleep at least once. beauty did not learn this proposition – she knew this all along. but it does not follow from this that her degrees of belief did not change. the distinction between learning a proposition and ‘learning’ a centered proposition does raise a serious worry, however. there are well established ddb arguments showing that one should accommodate newly learned propositions by conditionalizing upon them. in the preceding argu- ment, however, we have assumed that one should also conditionalize upon newly ‘learned’ centered propositions. to illustrate just how problematic this assumption is, note that before going to sleep, beauty believes with certainty that the centered proposition ‘today is sunday’ is true. upon awakening, she believes with equal certainty that this centered proposi- tion is false. this sort of complete turnabout is something that can’t be accomplished under normal conditionalization. it is simply not clear how our ordinary canons of rational belief formation are to be extended to our beliefs about our location within the world. thus, while i think that the foregoing argument suggests that the answer to the sleeping beauty puzzle is / , it is also serves to make clear why that puzzle is so perplexing. i will attempt to bolster the case for / by developing a novel argument in the next section. . the dutch book argument for / as we saw in section above, there is an apparent dutch book argument that upon awakening, beauty’s degree of belief in heads should be / . that argument is mistaken. an essential constraint on dutch book argu- ments is that the bookie not exploit any information that is not available to the agent being booked. it is not an agent’s susceptibility to a sure loss per se that renders the agent’s degrees of belief incoherent. for one thing, she could protect herself against dutch books by abstaining from gambling. christopher hitchcock rather, susceptibility to dutch book is symptomatic of an underlying eval- uative inconsistency. on the one hand, the agent views a book of bets as fair – she judges each individual bet as yielding no expected loss or gain for either side. on the other hand, she views the book of bets as unfair – she can determine that a loss is inevitable using purely deductive reasoning, which does not presuppose probabilistic coherence. in the dutch book arguments, the bookie is a colorful device for bringing out this second evaluation. but the bookie’s certain gain is not an appropriate stand-in for the agent’s second evaluation if it depends upon information unavailable to the agent. if the bookie can achieve his certain gain only by exploiting information that is unavailable to the agent, then the dutch book reflects an evaluation of the system of bets that is not the agent’s own. in the sleeping beauty puzzle, the bookie cannot be allowed to know the outcome of the coin toss. moreover, when he sells the second bet to beauty upon awakening, he cannot be allowed to know what day it is. if beauty knew what day it were upon awakening, that would be relevant to her degree of belief in heads; if she knew it were tuesday, for example, her degree of belief in heads would be zero. thus the bookie cannot know the day of the week without being in possession of relevant information that is unavailable to beauty. but now let us ask, how can the bookie arrange to sell the second bet to beauty without violating this restriction? that is, how can the bookie formulate an appropriate dutch strategy? he cannot simply plan to show up on monday at noon, for then he will be selling the bet in the full knowledge that it’s monday. nor can he arrange to go on either monday or tuesday, selected at random, while somehow remaining ignorant of what day it is. in this case, he risks showing up on a tuesday when the outcome of the coin toss was tails, in which case he loses the first bet and never gets to sell the second. there is one way in which the bookie can ensure that he has no inform- ation that is unavailable to beauty: he can sleep with her. that is, he can place his first bet, go into a deep sleep when beauty does, arrange to have himself awakened under the same protocol as beauty, and sell a follow-up bet to beauty whenever they wake up together. the bookie, like beauty, will awaken having no idea whether it is the first or second awakening, having no idea whether an initial follow-up bet has already been placed. thus he must sell the same bet to beauty whenever they both wake up. under this arrangement, the bookie will end up selling two follow-up bets to beauty if they wake up together twice; this will happen precisely if the outcome of the coin toss is tails. if the bookie follows this strategy, he can sell a dutch book to beauty if her degree of belief in heads upon awakening is / , but not if it is / . beauty and the bets table ii bets payoff cost heads tails bet # $ if tails $ −$ $ bet # $ if heads $ $ −$ bet # $ if heads $ if tails −$ only placed and tails if tails combined $ if heads $ if heads −$ $ if tails $ if tails −$ that is, once we take care to specify just how the bookie arranges to sell all his bets, it turns out that the dutch book argument favors the answer / , rather than / . here is how beauty can be made to pay if she keeps her degree of belief constant at / . before going to sleep, the bookie sells beauty bet # , with a cost of $ , and a payoff of $ if the coin lands tails. every time they wake up together, the bookie sells a follow-up bet, costing $ , and paying $ if the coin landed heads. if they wake up once, he will sell her one such bet; if they wake up twice, he will sell her two. thus, if the outcome is heads, beauty will lose the first bet, and win one follow-up bet; her winnings will be $ , but she will have paid $ for the two bets. if the outcome is tails, beauty will win the first bet, and lose two follow-up bets; she will win $ , but will pay out a total of $ . either way, beauty loses $ . the bookie has arranged it so that the combined stake of the follow-up bet(s) is correlated with the outcome. these results are summarized in table ii. a similar story can be told without invoking a sleeping bookie. sup- pose, before going to sleep, we were to ask beauty whether she thought that the foregoing betting strategy was fair (regardless of whether she would actually take those bets). she would be unable to arrive at a single answer. on the one hand, she would find every individual bet fair in light of the information available to the agent at the time. on the other hand, she would be capable of doing the math and determining that the strategy doomed the bettor to a certain loss. thus beauty’s degrees of belief would not allow her to consistently evaluate this betting strategy. analogous prob- lems arise if beauty changes her degree of belief in heads to any value other than / . christopher hitchcock table iii bets payoff cost heads tails bet # $x if heads $x/ $x/ −$x/ bet # $y if heads $y/ $ y/ −$y/ bet # $y if heads $y/ if tails −$y/ only placed and tails if tails combined $(x + y) if heads $(x/ + y/ ) $(x/ + y/ ) if heads $ if tails $(x/ + y/ ) −$(x/ + y/ ) if tails by contrast, if upon awakening beauty’s degree of belief in heads is / , she cannot be caught by such a dutch strategy. suppose that the first bet sold by the bookie pays $x if the coin lands heads; then beauty’s fair price for this bet is $x/ . if x is negative, this is equivalent to a bet on tails with payoff $|x| and cost $|x/ |. the follow-up bets will pay $y if the coin lands heads, and will cost $y/ . if the coin lands heads, she will ’win’ the first bet (actually a loss if x is negative), and will win one follow-up bet, for a gross gain of $(x + y), and a cost of $(x/ + y/ ). if the coin lands tails, she will lose three bets – the first bet plus two follow-up bets – for a gross gain of zero, and a cost of $(x/ + y/ + y/ ). thus her net ‘profit’ (possibly negative) is $(x/ + y/ ) if the coin lands heads, and −$(x/ + y/ ) if the coin lands tails. these results are summarized in table iii. in order for beauty to suffer a guaranteed loss, x and y need to be chosen so that both $(x/ + y/ ) and −$(x/ + y/ ) are negative. since the one net payoff is just the negative of the other, there is no way to make them both negative. a properly constructed ddb argument thus reinforces the argument from symmetry presented in the previous section: beauty’s degree of belief upon awakening should be / . i have made no attempt to show that there is no way that the bookie can arrange to make exactly one follow-up bet without violating the strictures against extra information. here is one possibility: the bookie sells his first bet to beauty before going to sleep. he plans to go to sleep when beauty does, and arranges to be awakened on monday, but not on tuesday. be- fore going to sleep, beauty is told of these arrangements. shortly before waking up, however, both beauty and the bookie are given a drug that beauty and the bets makes them forget the nature of the arrangements that were made (and hence to be uncertain about whether it is monday or tuesday). the bookie then sells his second bet. in this manner, the bookie could sell the system of bets comprising the dutch book of section . and it seems as though the bookie is never in possession of information that is lacking to beauty. does this strategy provide us with a rival dutch book argument, support- ing the answer / ? the case is problematic. first, how does the bookie know to sell the bet on monday? for all he knows, he has already sold the second bet, and to sell yet another would endanger his certain profit. second, suppose that the outcome of the coin toss is tails, so that beauty is awakened on tuesday while the bookie continues to doze. there is one sense in which he has no information lacking to beauty: he is fast asleep. on the other hand, he is behaving just as though he has been given the information that he is not awake, and is using this information to avoid selling a second follow-up bet on tuesday. in general, it is just not clear what counts as ‘information’ in this sort of scenario; indeed, this is one of the features of the puzzle that makes it so interesting. in the absence of any detailed solution to this problem, it seems that the only way to ensure that the ‘no extra information’ clause is satisfied is to have the bookie undergo the same protocol that beauty does. . morals for those who are persuaded by ddb arguments in general, the argu- ment of the previous section shows that the correct answer to the sleeping beauty puzzle is / ; and as i will argue shortly, even those who are nor- mally skeptical of ddb arguments have less reason to be skeptical of this particular instance. but first let us review the other arguments that were presented in sections two through five. the frequency argument of section two is clearly flawed. one cannot simply infer from the fact that the long-run relative frequency of heads awakenings is / , to the conclusion that the probability of heads on some particular awakening – the very first awakening, as the problem is set up – is one-third. however, this argument does contain a grain of truth. the ddb argument of the previous section hinges on the fact that the bookie can place two follow-up bets if the coin lands tails, and only one if the coin lands heads. thus the actual number of awakenings that occurs in the two different outcomes does play a central role in the solution to the problem. the argument of section three fails, because it wrongly assumes that beauty acquires no new information upon waking up. she undergoes a transition from believing the centered proposition ∼ a to believing the christopher hitchcock centered proposition a. while this may not be learning in the normal sense, it does reflect a change in beauty’s overall beliefs. the ddb argument of section four fails, because the bookie is only able to formulate an appropriate dutch strategy by exploiting information that will be unavailable to beauty. this means that the dutch strategy is not one that beauty would simultaneously evaluate as being both fair and unfair. the symmetry argument of section five is problematic for at least two reasons. first, it makes assumptions about the nature of beauty’s ’prior’ degrees of belief. these are not simply beauty’s degrees of belief at some specific time, say on sunday before the experiment begins. they are rather beauty’s degrees of belief in the absence of any temporal information. these are much harder to construe than temporally located degrees of belief; indeed, they are degrees of belief that beauty may never actually possess. second, it was assumed that beauty assimilated newly ‘learned’ centered propositions by conditionalization. this cannot be right: condi- tionalization can never allow us to pass from certainty in the truth of a proposition to certainty in its falsehood (or vice versa), while it is possible to make this transition upon learning a centered proposition. despite these flaws, the argument of section five seems not to have led us astray, so perhaps our assumptions are innocuous after all. in addition to shedding light on the sleeping beauty problem, the argu- ment of section six also illustrates the care that must be undertaken when wielding dutch book arguments. in particular, the strategy of having the bookie adhere to the same protocol as the agent is a useful way to en- sure that the bookie has no information that is unavailable to the agent. consider, for example, the following counterexample to the reflection principle due to talbott ( ). let s be the proposition that mary ate spaghetti for dinner last night, and suppose that mary is almost certain ( . ) that s is true. let t be the present, and let t′ be some time one year in the future. mary knows that at time t′, she will no longer re- member what she ate for dinner last night. perhaps at time t′ her degree of belief in s will be . . then mary’s present degree of belief will be pt (s|p(s, t ′, . )) = . , in violation of reflection. can a dutch book be made against mary? apparently so: the bookie sells to her a bet on s at time t, and then sells to her a bet on ∼ s at time t ′ so as to ensure a net loss. but has the bookie exploited information that is presently unavail- able to mary? presumably, at time t′, mary has not only forgotten what she ate for dinner on that night so long ago, but she has also forgotten which bet she bought on the following day. if she could recall that she bought a bet on s, despite being offered very unfavorable odds, she would reasonably beauty and the bets infer that s is (very probably) true. so suppose we require that the bookie also forget which bet he sold at time t. then he would not know which bet to sell her at time t ′ so as to complete the dutch book. thus the bookie cannot sell the dutch book to mary without exploiting information that is unavailable to her. thus this is not a case where the application of the reflection principle can be justified by appeal to a ddb. this discussion should provide some solace to critics of ddb argu- ments (see e.g., bacchus et al ; christensen ; howson ). we do indeed have reason to be suspicious of blanket ddb justifications of principles such as reflection. although an agent will be vulnerable to a ddb whenever her degrees of belief violate reflection, there may nonetheless be situations in which she violates that principle, while re- maining invulnerable to a ddb of the appropriate sort. that is, an agent may violate reflection without being involved in the sort of evaluative inconsistency that is normally the root cause of dutch book vulnerability. the case described by talbott has just this structure. it follows that those who are skeptical of ddb arguments generally need not be skeptical of the specific ddb argument presented in section . that argument was not offered in blanket support of a generic principle of rationality, but was offered to justify the appropriateness of a specific degree of belief in a specific scenario. some will remain skeptical of my argument anyway; even for these holdouts, there is a moral to be drawn. the argument shows that beauty’s situation is importantly different from one in which an agent simply learns nothing. in the latter case, an appropriate ddb argument could be con- structed to support the answer / . even those who do not find ddb arguments compelling for purposes of establishing appropriate degrees of belief must grant that a belief change in which an agent is subject to a ddb is structurally different from one in which she is not. moreover, even those who are skeptical of the idea that beauty has ‘learned’ a new centered proposition must recognize that beauty’s epistemic state is interestingly different from that of an agent who has simply learned nothing. i will conclude by drawing attention to a rather striking feature of the ddb argument that the reader might well have missed. the argument of section six did not invoke any of the symmetry assumptions of section five. in particular, the ddb argument did not make use of the fact that beauty’s ‘priors’ were such that p (sun) = p (mon) = . . . = / . rather, this symmetry assumption is supported by the ddb argument. suppose, for example, that p (mon) = . and p (t ues) = . . then, making the other assumptions in section five, beauty’s degrees of belief upon awakening will be: p (mon&t |a) = . , p (mon&h |a) = . , christopher hitchcock p (t ues&t |a) = . . this would leave beauty with a degree of belief in heads equal to . . with this degree of belief, beauty would be vulnerable to a ddb. thus, if the framework of section five is the correct one for representing this problem, then the ddb argument shows that she must assign equal ‘priors’ to mon and t ues. this is unusual: an agent’s prior probabilities are not normally considered to be subject to the canons of probabilistic rationality (with the exception that tautologies and contradic- tions receive priors of and , respectively). if the agent, knowing nothing at all about a coin that is about to be tossed, nonetheless has a degree of belief of . that the coin will land heads, that is her business. such a degree of belief might be unmotivated, but it is not incoherent. indeed, this latitude with respect to prior probability assignments is often considered a weakness in the bayesian program. by contrast, in the sleeping beauty problem, symmetry with respect to degrees of belief about one’s location in time is required for coherence. presumably, these symmetry constraints arise because both monday and tuesday will eventually come to pass; there is no analogous inevitably involving the outcomes of a coin toss. uncertainty about one’s location within a possible world adds a dimen- sion of complexity to traditional problems in epistemology and decision theory. the sleeping beauty problem and its solution illustrate this point beautifully. acknowledgments for discussion and comments i would like to thank three anonymous ref- erees as well as alan hájek, matthias hild, jim joyce, brad monton, john o’leary-hawthorne, bas van fraassen, susan vineberg, and especially adam elga. notes while remaining unaware that it is monday, of course. for the unwashed, a dutch book is a system of bets such that the agent is guaranteed to suffer a net loss if she purchases all of them. a diachronic dutch book is one in which the bets are placed at different times. an agent is susceptible to a dutch book if she finds every bet comprising the book to be fair. it is assumed the agent finds fair a bet on proposition a with payoff q and cost qp (a), where p (a) is the agent’s degree of belief that a is true. proof: by (i) and (v), we must have (∗) p (mon, h ) + p (t ues, h ) = p (mon, t ) + p (t ues, t ). by (ii), we must have (∗∗) p (mon, h ) = p (mon, t ) + p (t ues, t ). it follows from these two equations that (∗∗∗) p (t ues, h ) = (perhaps the halfer could motivate this value by appeal to the impossibility of beauty’s learning 〈t ues, h 〉). from beauty and the bets (iii) and (∗∗∗) we get p (mon, h ) + p (mon, t ) = p (t ues, t ). (since (∗∗∗) implies that p (t ues) = p (t ues, t ).) subtracting (∗∗) from (∗∗∗∗) we get p (mon, t ) = −p (mon, t ) = , in violation of (iv). qed lewis ( ) does not make this mistake: he very clearly distinguishes the conditional and unconditional evidential relevance, and very clearly asserts that he believes in both. rather, it seems to me that he just has the bizarre intuition that ‘today is monday’ is evidentially relevant to ‘the coin landed heads’, whereas ‘either today is monday, or today is tuesday and the coin landed tails’ is not. bartha and hitchcock ( ) argue that a similar mistake is implicated in leslie’s doomsday argument (leslie ): the evidential relevance of my time of birth for doom given that i am born at all is mistaken for the unconditional relevance of my time of birth for doom. indeed, there are many interesting parallels between the two puzzles, but a detailed exploration of these will have to await another occasion. see monton ( ) for an interesting discussion of the relationship between the two different kinds of learning. this interpretation of what dutch book arguments show isn’t newfangled; it dates back to the origin of the dutch book arguments in ramsey ( ). where ‘last night’ picks out a particular night rigidly. the bookie also needs to sell her a side bet on p(s, t ′, . ) at timet . this will protect him in case mary’s degree of belief is s at time t ′ is not . . note that this only helps mary in the case where she actually does forget which bet was made. if she and the bookie both do remember, and she thereby resets her degree of belief in s to . , then she will lose money due to the side bet described in the previous footnote. thanks to susan vineberg for pointing this out. ‘so much the worse for reflection’ or ‘so much the worse for the putative counter- example’? on the one hand, this argument removes one sort of objection to the reflection principle; on the other hand, it narrows the scope of the principle. how narrow? i doubt that it is possible to provide any one simple criterion for when the principle applies and when it doesn’t. for example, the line of argument given above will not help with christensen’s lsq example ( ). the difference between memory loss and intoxication is that in the latter case it would be of no help to be reminded of one’s former opinions. this seems to be the sort of evaluation that needs to be made on a case-by-case basis. at any rate the assumption that p (mon) = p (t ues) is so supported. references aumann, r., s. hart, and m. perry: , ‘the forgetful passenger’, games and economic behavior , – . bacchus, f., h. kyburg, and m. thalos: , ‘against conditionalization’, synthese , – . bartha, p. and c. hitchcock: , ‘no one knows the date or the hour: an unorthodox application of rev. bayes’s theorem’, philosophy of science , s –s . christensen, d.: , ‘clever bookies and coherent beliefs’, the philosophical review , – . elga, a.: , ‘self-locating belief and the sleeping beauty problem’, analysis , – . christopher hitchcock howson, c.: , ‘dutch book arguments and consistency’, in d. hull, m. forbes, and k. okrulik (eds.), psa ,vol. ii, east lansing, philosophy of science association, pp. – . leslie, j.: , the end of the world, new york, routledge. lewis, d.: , ‘a subjectivist’s guide to objective chance’, in r. jeffrey (ed.), studies in inductive logic and probability, vol. ii. berkeley: university of california press, pp. — . reprinted in d. lewis, philosophical papers, vol. ii, oxford: oxford university press, pp. – . lewis, d.: , ‘sleeping beauty: reply to elga’, analysis , – . monton, b.: , ‘sleeping beauty and the forgetful bayesian’, analysis , – . piccione, m. and a. rubinstein: , ‘on the interpretation of decision problems with imperfect recall’, games and economic behavior , – . quine, w. v. o.: , ‘propositional objects’, in ontological relativity and other essays, new york, columbia university press, pp. – . ramsey, f.: / , ‘truth and probability’, in d. h. mellor (ed.), philosophical papers, cambridge, cambridge university press, pp. – . talbott, w.: , ‘two principles of bayesian epistemology’, philosophical studies , – . teller, p.: , ‘conditionalization and observation’, synthese , – . van fraassen, b.: , ‘belief and the will’, the journal of philosophy , – . division of humanities and social sciences - california institute of technology pasadena ca u.s.a. e-mail: cricky@caltech.edu polyhedra through the beauty of wood bob rollings brimorton drive scarborough, on, m g t , canada abstract this paper has been prepared to demonstrate how i have used the geometry of polyhedra and my chosen medium of lathe turned wood to present the models shown in an aesthetically pleasing and artistic way. each of the five platonic solids (tetrahedron, hexahedron, octahedron, docedahedron and icosahedron) has been interpreted through the eyes of a woodturner allowing the viewers alternate perspectives of these classic polyhedra. the description of each model includes details such as the type of wood used, dimensions and the process of fabrication. introduction my interest in geometry stems no doubt from a lifetime spent in the cabinet making industry. initially i worked as a hands-on craftsman and then later in a supervisory position which consisted of interpreting designer/architectural concepts and turning them into practical and beautiful pieces. after my retirement in , i turned my interest in geometry into a hobby, using wood as a medium and a lathe as one of my many tools. i started a second journey of discovery as a wood turner/artist. my investigation and interpretation of the platonic solids has been influenced by johannes kepler, luca pacioli, leonardo de vinci, m. c. escher, and later by buckminster fuller and donald coxeter. after exhibiting some of my work at the fields institute i was invited to share space in donald coxeter’s showcase in the math department at university of toronto where i currently have four pieces on display. the five platonic solids are the tetrahedron, hexahedron (cube), octahedron, dodecahedron and icosahedron. the properties of the platonic solids are that each of the faces is regular, the faces are identical, and at each vertex the same number of faces meet. each pair of adjoining faces meet at the same angle and the vertices lay on the surface of a sphere. tetrahedra figure is a simple tetrahedron model, which has been made of pear wood. each of the faces is an equilateral triangle of about inches long. the faces were cut using a template on a table saw with the mitre angle being . degrees. the angle was originally obtained from table [ ] and then adjusted if required based on dry fitting the pieces. the piece was then glued and the holes were cut only to show that it is a hollow form. the two tetrahedra shown in figure have turned spindles representing the edges. this type of model can be referred to as the web of the polyhedral form. the spindles, figure : a simple tetrahedron bridges : mathematics, music, art, architecture, culture which are / ” in diameter, have tenons turned on each end fitting into holes drilled into the ½ inch spheres representing the vertices. the angle and the spacing of the three drilled holes is critical. the angles were approximated and then confirmed using cardboard models and a master block was produced. the holes were then drilled using the angled block and an indexing system to ensure equal spacing of the holes. this process was used to create other polyhedral spindle figures by producing other master blocks of appropriate angles and indexing. the tetrahedron in figure was initially turned as a inch walnut sphere. the four vertices were located using a compass. the compass is set using the diameter of the sphere divided by . , which in this case is . inches. the first vertex was used as the starting point and a circle was scribed on the sphere. the second vertex is any point on the scribed circle. by rotating the compass left and right, the third and fourth vertices are established. if the setting on the compass is correct, this line will have been divided into three equal parts and you have located the four vertices of a tetrahedron. the sphere was then hollowed out to a wall thickness of about ¾ inch, leaving enough wood to carve the double twists, which connect the vertices. the twists were cut freehand using a dremel burr. hexahedra the inch cube in figure is a hexahedron designed to be a secret box. made of applewood, its six faces are identical and one of them is also a screw-in panel. each face is inscribed with two logarithmic spirals textured with a rotary burr prior to being highlighted with black acrylic paint. the logarithmic spirals were developed by repetitive division of a rectangle conforming to the proportion of the golden mean [ ]. the spirals were transferred to the figure by rotating the template degrees around the centre of each face. figure : two web tetrahedral figure : artistic tetrahedral figure : hexahedron box octahedra the grouping shown in figure was one of my first attempts at working with platonic solids. although they appear to be one octahedron and three spheres, all four started as octahedra each having eight equilateral triangular faces. the name “the family” comes from the idea that all the boxes come from the same original form. rollings three of the octahedra were lathe turned to their spherical shapes what sets them apart is the species of wood and the manner in which the lids are oriented. for the lower box i used becote and divided it at the equator; four sections for the lid and four sections for the bottom. for the middle box i used laurel and used two sections for the lid and six sections for the bottom. for the upper box i used wenge. again, there were four pieces for the lid and four pieces for the bottom, the difference being the orientation of the triangles, which produces the zig-zag edge when the lid is removed this octahedron in figure was inspired by a traditional quilting design known as tumbling blocks. the technique used is referred to as stickware or tunbridgeware as it has been made up from a bundle of sticks. in this case, the sticks are rhomboids cut at degrees with each of the faces being of equal length. a group of three made of three different colours of wood can be bundled together, the end view creating the optical illusion of a cube. the next step is to rebundle them together to make a triangular stick, which can then be cut into identically patterned slices. eight of the resulting equilateral triangles are mitred and glued together to produce an octahedron. the woods in this case are holly, white oak and cocabola. dodecahedra the dodecahedron in figure came about when i made stickware for some spinning tops. having enough left over for faces, i decided to make this dodecahedron. i took the ten sided stick and clad it with five pieces of oak to construct the pentagonal stick. from this stick i cut panels, each / inches thick, to make the dodecahedron. the woods used are holly, cocabola, pear, white oak, and maple, and it is about inches in diameter. figure is titled piece-peace suspended. this title is intended to be a play on words. as you can see, the dodecahedron box is suspended. each face of the dodecahedron is a pentagon, which is a symbol of peace. the box was intended to symbolically contain george’s weapons of mass destruction but when you look inside, the box is empty. the web, made of ebony, represents the web of evil. the handle, which is a dove, but not the white dove of peace, is made from the same black ebony. figure : the family figure : stickware octahedron figure : stickware dodecahedron figure : piece-peace suspended polyhedra through the beauty of wood figure is a stellated dodecahedron. the term stellated was coined by johannes kepler [ ]. stellation is a process that allows us to derive a new polyhedron from an existing one by extending the faces until they re-intersect. the flat planes, which emerge from these figures, enable this piece to be produced using the lathe or the bandsaw; i opted for the latter. the first step is to create a sphere and then locate the vertices. the compass setting is calculated using the diameter of the sphere times . [ ] and an initial circle is scribed on the sphere. choosing any point on the initial circle, a second circle is scribed creating two intersection points. circles are drawn from each point where two circles intersect. each point of intersection becomes a vertex. at the end of this process, the twelve vertices will have been located. holes were drilled at each of the vertices and a temporary rod was inserted to act as a pivot while cutting the faces on the bandsaw. a jig was used to control the depth of cut on all axes and as the wood fell away a dodecahedron emerged. the holes were plugged using contrasting coloured wood for emphasis. icosahedra the simple web of the icosahedron (figure ) emphasizes the symmetry and balance of all of the platonic solids. the web is created using spindles and spheres for the vertices as previously described with the only difference being the angles at which they are drilled and the number of holes drilled. the spindles are made from rose wood and the spheres at the vertices are boxwood. the piece is about inches in diameter. the sphere in figure was initially a faceted icosahedron made from curly maple. the joints have been emphasized with a laminate of black, white, and black veneer. the vertices were drilled out and replaced with black inserts. centered on each insert are hand turned flowers of several designs and a variety of woods. figure is a stellated icosahedron, which began as a solid sphere made from madrone. the faces were then cut on the bandsaw using a similar technique described for figure . in this case there are pivot points of rotation located in the valleys, which can be seen as the black caps of ebony. the base is made of walnut and was made on the lathe, using a swing pivot router, then painted black. the finished piece is inches high. figure : stellated dodecahedron figure : web icosahedron figure : spherical icosahedron figure : stellated icosahedron rollings figure is a combination of a stellated and a concave icosahedron. all of the panels used to make this piece are / inch thick. there are flat panels required to construct the piece. it is about . inches from point to point. the panels are mitre cut using a template and glued together. figure : stellated and concave icosahedron hybrids in the following pieces i have used the solid faces of the platonic solids surrounded by web models. i call these designs hybrids. in figure we have compounds of two tetrahedra constructed from eight minor tetrahedra; four of which are walnut, and the other four are maple. one of the vertices of each of the eight minor tetrahedrons becomes the corners of a hexahedron. i have joined these together using applewood spindles to reinforce the relationship. this stellated dodecahedron in figure has been made up of / inch babinga panels; five panels for each pyramid with a total of panels. the vertices give us the framework for the web, which as you can see is an icosahedron. the spindles and spheres are rosewood. the piece shown in figure was completely turned on the lathe. it was inspired by wenzel jamnitzer who was a german etcher/goldsmith and drew this piece in [ ]. i can only assume it was never made and that it was only a graphic design as the main body only hovered above the base. the wood for the core icosahedron is honey locust and the web and base were made in cocabola. web models the following four pieces have been modelled using a web design. they consist of more artistic interpretations of the platonic solids and were done using webs so that the entire shape, as in line drawings, are visible from a single perspective. figure : tetrahedron- hexahedron hybrid figure : dodecahedron- icosahedron hybrid figure : totally turned polyhedra through the beauty of wood this is a web model of a stellated icosahedron (figure ). it is interesting to see that when the faces are stellated to create new vertices we begin to see a relationship between the icosahedron and the dodecahedron. there are planes where pentagons are formed. the vertices of the stellated icosahedron are created by extending the edges of these pentagons. the ratio of the length of the spindles to the length of the base conforms to the golden mean. after completing the work shown in figure , i saw further possiblilities and so created metamorphosis (figure ). the relationship between the dodecahedron and icosahedron fascinated me. it began with a central dodecahedron. in the centre of each of the faces, spindles were projected to create the vertices of the icosahedron. finally the icosahedron was stellated to create the vertices of the outer dodecahedron. the web was then connected between these vertices completing the metamorphosis. johannes kepler lived from to , had a great interest in the platonic solids, and was the inspiration for this piece. it was his contention that the orbits of the planets are related to the platontic solids. in figure , each of the platonic solids are contained within one another and each rotate on their own axis. from the centre working out we have the tetrahedron, hexahedron, octahedron, dodecahedron and then finally the icosahedron. each rotates, as do the heavenly bodies. this piece has a total of spindles and vertices. the spindles and the circular frame are brazilian rosewood, the vertices are boxwood and the base is black painted hardwood. figure is an example of a progressive web transformation. the centre is an octahedron, which has been converted by making each of the eight faces into tetrahedrons. four were made from ebony and four from holly. these not only express two major intersecting tetrahedrons, but also indicate the eight vertices of the hexahedron. the various woods used here are pear, ebony, holly, and satinwood. the circular frame is walnut and the base is black-painted hardwood. this piece has found a home in donald coxeter’s showcase of models, at the university of toronto’s math department. figure : stellated icosahedron figure : metamorphosis figure : kepler theory figure : transformation rollings the following two pieces have been inspired by luca pacioli’s publication of de divina proportiona, published in in which leonardo de vinci drew the illustrations of the regular solids. leonardo’s drawings are probably the first illustrations of skeletonic solids. figure is similar to de vince’s model and my interpretation of the piece is constructed of individual frames mitred together. the side angles had to be cut prior to assembly. after the first row of frames had been glued together the other rows could be glued and assembled until the sphere was closed. all faces of the strips used for the frames were prefinished prior to assembly as all faces can be seen. the sphere was made from babinga wood and has a inch diameter. the base is turned from walnut and has been weighted with lead shot to permit the piece to be shown in an offset position. the second of leonardo’s pieces is a torus. this is his mazzocchio which he drew in solid edge form. it consists of sections around the circumference (figure ). each section contains eight frames for a total of frames, each with specific side angles. this model is made from zebra wood and is inches in diameter. figure shows a web model of buckminster fuller’s vector equilibrium [ ], which is a polyhedron. it is a cuboctahedron with all the vertices connected to the centre. it has many unique properties; it has vertices, which lie on the surface of a sphere. it contains edges as well as faces. vector equilibrium is comprised of eight tetrahedrons and six half octahedrons. finally, the distance from any two adjoining vertices is identical to the distance from any vertices to the central sphere. the piece rotates within its circular oak frame, which in turn pivots in the base. figure : de vinci model figure : de vinci torus figure : vector equilibrium this article has described many of the polyhedra and platonic solids i have worked on in the past few years and is also the result of much reading on the subject. the journey is endless and the variables infinite. polyhedra through the beauty of wood references [ ] j. cox, beyond basic turning, pp. . . [ ] r. lawlor, sacred geometry, pp. - . . [ ] p. cromwell, polyhedra, pp. - . . [ ] d. sprigett, woodturning wizardry, pp. - . [ ] p. cromwell, polyhedra, pp. . . [ ] r. buckminster fuller in collaboration with e.j. applewhite, synergetics, pp. . . rollings nv-ng .indd n e w s a n d v i e w s volume | number | february | nature genetics to phosphorylate itself and its downstream targets, and this could be part of its mecha- nism for inhibiting the activation of dna- repair complexes both at telomeres and at double-strand breaks. the demonstration by bradshaw et al. that trf is rapidly recruited to generic double-strand breaks will initiate a mutually productive period of interaction between the fields of dna repair and telo- mere biology, as the roles for telomeric fac- tors in the choreography of repair come into the spotlight. . bradshaw, p.s., stavropoulos, d.j. & meyn, m.s. nat. genet. , – ( ). . de lange, t. nat. rev. mol. cell. biol. , – ( ). . griffith, j.d. et al. cell , – ( ). . stansel, r.m., de lange, t. & griffith, j.d. embo j. , – ( ). . hardy, c.f., sussel, l. & shore, d. genes dev. , – ( ). . silverman, j., takai, h., buonomo, s.b., eisenhaber, f. & de lange, t. genes dev. , – ( ). . xu, l. & blackburn, e.h. j. cell. biol. , – ( ). . van steensel, b., smogorzewska, a. & de lange, t. cell , – ( ). . wang, r.c., smogorzewska, a. & de lange, t. cell , – ( ). . gommers-ampt, j., lutgerink, j. & borst, p. nucleic acids res. , – ( ). . steinert, s., shay, j.w. & wright, w.e. mol. cell. biol. , – ( ). . karlseder, j. et al. plos biol. , e ( ) the beauty of admixture ariel darvasi & sagiv shifman admixture mapping is an old concept that has only now been applied with markers across the entire genome. such a study scanning an african american population identified two chromosomal regions affecting susceptibility to hypertension. anecdotally, children of parents of mixed ethnicities are exotically beautiful. more sci- entifically established is the merit of admixed populations for gene mapping purposes. the potential value of admixed populations was suggested more than half a century ago . substantial theoretical and practical aspects have been developed since then (reviewed by mckeigue ). a genome scan to identify genes affecting a complex trait is now pre- sented for the first time to our knowledge by xiaofeng zhu and colleagues on page of this issue . the admixed population the concept behind admixture mapping is simple (fig. ). in essence, admixture map- ping is most similar to linkage analysis in experimental crosses with inbred strains, with specific similarity to advanced inter- cross lines . an advanced intercross line is a population derived from two inbred strains that were randomly intercrossed for several generations. an advanced intercross line constitutes the ideal admixed population: all variations can be identified in one of the two progenitors, the mean ancestral composition is % for each progenitor, allele frequencies in the progenitor populations are either or , and random mating is followed after a sin- gle generation of intercrossing the progeni- tors. in a human admixed population, these ideal conditions will never be met, resulting in decreased power for mapping purposes. except for gene effect, which has a strong influence on power, the parameter that mostly affects power, specifically in admixture map- ping, is the extent of difference in allele fre- quency between the ancestral populations . ariel darvasi is in the life sciences institute, the hebrew university, jerusalem , israel. sagiv shifman is in the wellcome trust centre for human genetics, oxford ox bn, uk. e- mail: arield@cc.huji.ac.il, sagiv@well.ox.ac.uk case control population population disease gene location figure schematic of one chromosome pair from each of several individuals in an admixed population. a group of cases (for a given disease) and a group of controls are separately presented at the bottom left and the bottom right, respectively. for one of the control individuals (arrow), a schematic presentation of all its ancestors in the last four generations is shown in the upper part of the figure. admixture mapping can be ideally applied if population (blue) and population (red) carry a different allele at the disease locus (dashed line). whole-genome scanning under the admixture mapping strategy consists of scanning the genome and identifying the regions with an excess of ‘red’ ancestry in the cases versus the controls, assuming that the ‘red’ population carries the predisposition allele. the size of the blocks from different ancestors will depend on the number of generations since the populations were mixed. © n a tu re p u b li s h in g g ro u p h tt p :/ /w w w .n a tu re .c o m /n a tu re g e n e ti c s n e w s a n d v i e w s nature genetics | volume | number | february for example, in the extreme case where the allele affecting a disease has the same fre- quency in both ancestral populations, admix- ture mapping cannot be efficiently applied. in contrast, the power of admixture mapping will be only mildly affected by the percentage contributed by each population to the admix- ture, as long as that proportion is between % and % (ref. ). genome scan for hypertension in an effort to identify chromosomal regions affecting hypertension, zhu et al. carried out a genome scan with microsatellite mark- ers and a total of cases (hypertensives) and controls (normotensives). cases and controls were selected from the african american population. african americans are an admixed population with ∼ % african ancestry and ∼ % european ancestry and are thus appropriate for admixture mapping. all individuals were sampled from three net- works (gennet, genoa and hypergen) in geographically distinct locations participat- ing in the family blood pressure program. zhu et al. initially explored hyperten- sive cases only, independently in the three networks, and found an excess of african ancestry in more than one network on chro- mosomes , and . in particular, two markers around q showed an excess of african ancestry in all three populations. to validate the significance of these results, they compared the excess of african ances- try found in the cases with that found in controls. the excess of african ancestry was shifted upwards in cases relative to controls. the entire shift can be attributed to two chro- mosomal regions at q and q where the excess of african ancestry was signifi- cant in cases but not in controls. therefore, these findings suggest that the chromosomal regions q and q contain genes affect- ing predisposition to hypertension. support for the chromosome q findings can be drawn from previous linkage studies that found evidence for linkage between this chromosomal region and hypertension or related traits , . the large size of this chromosomal region ( cm, including all markers with z score > . ) may suggest that more than one gene affecting hypertension is present. this is not unexpected, as cis-acting linked genes will behave as a single gene with a larger effect (the combined effect of the two genes) in an admixture mapping experiment, hence having greater power of being picked up in a genome scan. the q region needs further replication to establish its validity, as this region has not previously been suggested to be associated with hypertension. a complementary approach two main approaches have been used to search for genes affecting complex traits: linkage analysis and association analysis . linkage analysis has two key disadvantages: relatively low statistical power for detecting modest effects , and low mapping resolution, which prevents gene identification even after a region has been detected . association anal- ysis also has two key disadvantages. because this approach is based on linkage disequilib- rium or on testing the potential functional polymorphisms, the number of polymor- phisms that need to be scanned in the entire genome is painfully high (> , ) . the second disadvantage is the diminishing power that occurs with high genetic heterogene- ity . admixture mapping is a strategy that falls between linkage analysis and association analysis in many respects (table ). although admixture mapping has a sub- stantially lower mapping resolution than association analysis, as long as genotyping costs are a limiting factor, admixture map- ping will be a good approach for the initial genome scan. admixture mapping is particu- larly appropriate for traits for which there is a large difference in the phenotypic prevalence in the ancestral populations of the admix- ture. nevertheless, admixture mapping is not limited to those traits and will still work if the allele frequencies of the disease locus are different in the ancestors of the admixed population. this is more likely to occur when the disease prevalence varies in the ancestral populations. given the advantages of admixture map- ping, it is notable that this experiment has only now been done. one reason for this might be the notion (which might be cor- rect) that more markers are required for an adequate whole-genome scan with admix- ture mapping than were used in the current experiment. in addition, admixture mapping is efficient only if the allele frequencies of the markers are substantially different in the ancestral populations. in that respect, it now seems that microsatellite panels might be more informative than originally thought . consequently, a standard panel of markers, normally used in linkage experiments, suc- cessfully served zhu et al. in their admix- ture mapping study. a word of caution is appropriate, though. the unexpected success might be due to the specific constellations particular to the current experiment, includ- ing chance. therefore, the study of zhu et al. , which applied admixture mapping to hypertension and concluded with success- ful and robust results, will still require some replications in other traits and with other samples before its generality can be estab- lished. the current results, however, are undoubtedly promising enough to encour- age the scientific community to carry out these essential replications. . rife, d.c. am. j. hum. genet. , – ( ). . mckeigue, p.m. am. j. hum. genet. , – ( ). . zhu, x. et al. nat. genet. , – ( ). . darvasi, a. & soller, m. genetics , – ( ). . patterson, n. et al. am. j. hum. genet. , – ( ). . destro-bisol, g. et al. hum. genet. , – ( ). . krushkal, j. et al. circulation , – ( ). . arya, r. et al. diabetes , – ( ). . lander, e.s. & schork, n.j. science , – ( ). . risch, n. & merikangas, k. science , – ( ). . risch, n.j. nature , – ( ). . weiss, k.m. & terwilliger, j.d. nat genet. , – ( ). . tang, h. et al. am. j. hum. genet. (in the press). table main characteristics of mapping strategies linkage analysis admixture mapping association analysis statistical power low high* high number of snps required for whole genome scan low low high sensitivity to genetic heterogeneity low moderate high mapping resolution poor intermediate good *power diminishes to zero with equal allele frequencies in the ancestral population. © n a tu re p u b li s h in g g ro u p h tt p :/ /w w w .n a tu re .c o m /n a tu re g e n e ti c s the idea of beauty and its biases: critical notes on the aesthetics of plastic surgery | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /gox. corpus id: the idea of beauty and its biases: critical notes on the aesthetics of plastic surgery @article{stefano theio, title={the idea of beauty and its biases: critical notes on the aesthetics of plastic surgery}, author={n. di stefano}, journal={plastic and reconstructive surgery global open}, year={ }, volume={ } } n. di stefano published medicine plastic and reconstructive surgery global open summary: two biases affect the idea of beauty often embodied in aesthetic surgery. the first one is that the living body is the sum of different parts; the second one claims that beauty results from the sum of beautiful elements. taken together, these biases explain most of the aesthetic surgery procedures, in which a localized improvement is supposed to impact on the whole body image. in this article, i put into question these problematic assumptions, showing that western and eastern… expand view on wolters kluwer doi.org save to library create alert cite launch research feed share this paper citations view all topics from this paper esthetics (discipline) note (document) body image citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency pilot study about the relationship between body perception and sexuality using the das m. barone, a. cogliandro, + authors p. persichetti medicine european journal of plastic surgery save alert research feed practical introduction to laser dermatology v. madan save alert research feed references showing - of references sort byrelevance most influenced papers recency how you become who you are: a new concept of beauty for plastic surgery v. tambone, m. barone, a. cogliandro, n. di stefano, p. persichetti computer science, medicine archives of plastic surgery pdf save alert research feed [aesthetic surgery, psychic preparation]. r feiss medicine annales de chirurgie plastique et esthetique save alert research feed managing the psychological aspects of plastic surgery patients. j. sykes medicine current opinion in otolaryngology & head and neck surgery save alert research feed the moral dimension of japanese aesthetics y. saito philosophy save alert research feed patient-reported outcome measures in plastic surgery: use and interpretation in evidence-based medicine a. pusic, v. lemaine, a. klassen, a. scott, s. cano medicine plastic and reconstructive surgery save alert research feed so you want to be better: the role of evidence-based medicine in plastic surgery. rod j. rohrich medicine plastic and reconstructive surgery save alert research feed wabi-sabi: for artists, designers, poets & philosophers l. koren engineering, art save alert research feed cartesian meditations: an introduction to phenomenology e. husserl, d. cairns psychology pdf save alert research feed patient-reported outcome measures in plastic surgery: use and interpretation in evidencebased medicine plast reconstr surg introduction to phenomenology gregory f. weis philosophy save alert research feed ... ... related papers abstract topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue flavour physics and the large hadron collider beauty experiment phil. trans. r. soc. a ( ) , – doi: . /rsta. . flavour physics and the large hadron collider beauty experiment by valerie gibson* department of physics, the cavendish laboratory, university of cambridge, cambridge cb he, uk an exciting new era in flavour physics has just begun with the start of the large hadron collider (lhc). the lhcb (where b stands for beauty) experiment, designed specifically to search for new phenomena in quantum loop processes and to provide a deeper understanding of matter–antimatter asymmetries at the most fundamental level, is producing many new and exciting results. it gives me great pleasure to describe a selected few of the results here—in particular, the search for rare b s → m+m− decays and the measurement of the b s charge-conjugation parity-violating phase, both of which offer high potential for the discovery of new physics at and beyond the lhc energy frontier in the very near future. keywords: large hadron collider beauty; flavour; charge-conjugation parity; lhcb . the beauty of flavour flavour physics plays a crucial role in the search for new phenomena at the large hadron collider (lhc). its pedigree is excellent, providing the first evidence for the existence of the charm quark, the third generation of quarks and leptons, the high mass scale of the top quark and matter–antimatter asymmetries through the discovery of cp violation. the nature of flavour physics is such that it allows one to probe processes at energies beyond the lhc centre-of-mass energy and therefore has an enormous potential to provide the first evidence for new physics, which may hold the key to open scientific questions such as ‘why are there three generations of quarks and leptons (if there are only three)?’, ‘what determines the hierarchy of quark masses?’ and ‘what is the origin of cp violation?’ furthermore, two of the very few observations that cannot be accommodated by the standard model (sm), namely the baryon–antibaryon asymmetry in the universe and the non-zero neutrino mass, are intimately related to flavour physics. *gibson@hep.phy.cam.ac.uk flavour is a label that distinguishes between the different members in the two groups of elementary particles, the quarks and leptons. the violation of the combination of discrete symmetries, charge conjugation (c) and parity (p), which leads to an asymmetry between matter and antimatter. one contribution of to a discussion meeting issue ‘physics at the high-energy frontier: the large hadron collider project’. this journal is © the royal society d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il mailto:gibson@hep.phy.cam.ac.uk v. gibson . . excluded area has cl > . excluded at c l > . . sin b |vub|tn |vub|sl dmd d md and d ms sol. w/cos b < (excl. at cl > . ) – . – . – . – . – . g a ek ek a b a g g . r– h– . . . figure . the current status of the unitarity triangle, taken from charles et al. [ ]. (online version in colour.) the heart of flavour physics in the sm lies in the very successful cabibbo– kobayashi–maskawa (ckm) picture of the interactions between the different quark flavours (see the review on the ckm quark-mixing matrix in nakamura et al. [ ]). the ckm matrix describes the relationship between the weak and mass eigenstates; it is unitary and incorporates cp violation through the complex phases of the matrix elements. the state-of-the-art knowledge is encapsulated in the so-called ‘unitarity triangle’ (figure ), which shows a consistency between all the experimental measurements made over many decades and is a beautiful validation of the ckm picture [ ]. even so, there is still plenty of room for new physics [ ] that may be uncovered in the near future by the lhc beauty (lhcb) experiment at the lhc. the main flavour physics programme of the lhcb experiment is to make very precise measurements of cp-violating asymmetries and to search for new phenomena in quantum loop processes using particle decays involving heavy (bottom and charm) quarks. the indirect approach taken by lhcb is complementary to the direct search for new physics by the general purpose detectors atlas (a toroidal lhc apparatus) and cms (compact muon solenoid), and will provide information about the masses, couplings, spins and cp phases of newly discovered particles. interestingly, if new particles exist at the tev mass scale, as is expected, then current measurements already indicate that the flavour couplings of the new physics have a very particular flavour structure so as not to have given rise to effects inconsistent with sm expectations. the minimal flavour violation (mfv) hypothesis, in which all sources of flavour and cp violation in the quark sector have the same pattern as the sm, namely the ckm matrix, has been proposed to resolve this dilemma (see references in charles et al. [ ]). one illustration of the power of flavour physics is therefore phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il flavour physics and the lhcb experiment demonstrated by measurement of the b d,s → m+m− decay rates, which are highly sensitive to new physics contributions but can also prove or exclude the mfv hypothesis by testing whether physics beyond the sm exhibits the characteristic flavour-universality pattern. . the lhcb experiment the lhcb experiment [ ] is designed to search for new physics and to make precision measurements of cp-violating asymmetries using the decays of hadrons involving bottom and charm quarks. the bottom quark (b quark) is of particular interest because — it resides in the third generation of elementary particles and is therefore intimately linked to cp violation; — it is the heaviest quark (mass approx. . gev c− ) that forms hadronic bound states; — it must decay to quarks outside the third generation, which means that its decay is suppressed resulting in an observable long lifetime (approx. . ps); — its high mass means that there are many accessible final states; and — all of the b-flavoured hadron species, such as b+(≡ b̄u), b d (≡ b̄d), b s (≡ b̄s), b+c (≡ b̄c) and lb(≡ bud), are produced in high-energy proton–proton (pp) collisions. the lhcb experiment provides a large acceptance for the decay products of b-flavoured hadrons and is optimized to select, reconstruct and identify the particles produced in the subsequent decay. the production of bb̄ pairs in pp collisions at the lhc is strongly peaked forward–backward and correlated, such that if the b quark goes in the forward direction, then so does the b̄ antiquark. the experiment is therefore configured as a forward single-arm spectrometer with excellent tracking provided by the high-precision silicon velo (vertex locator) detector and other tracking detectors, excellent particle identification provided by two ring-imaging cherenkov (rich) detectors, a calorimeter system and a muon tracking system, and a highly efficient trigger system. the velo and rich detectors, in particular, are critical to the success of the experiment. the velo detector provides a primary interaction vertex resolution of approximately mm (for tracks) transverse to the beam direction and approximately mm along the beam direction. the rich detectors provide charged pion–kaon particle identification over a large range of momentum ( – gev c− ). the results presented here were accomplished using the first pp collision data from lhcb and correspond to an integrated luminosity of approximately pb− (equivalent to approx. bb̄ pairs) collected during ; one of the first pp collision events observed in lhcb is shown in figure . owing to the design of the experiment and a three times higher bb̄ cross section at the lhc [ , ], lhcb is already competitive with the tevatron experiments at fermilab, which has analysed pb− of data collected over many years. at the time of writing, the lhcb experiment is running smoothly and expects to collect approximately pb− by the summer of and fb− by the end of the year. phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il v. gibson lhcb event display . . run event bid : : figure . an event display of one of the first pp collisions observed in the lhcb detector. (online version in colour.) (mevc– )mj/ψφ (before φ bias correction) ev en ts / ( m ev c – ) s = tev data preliminary lhcb – j/ψφ proper time (ps) ev en ts / ( . ps ) preliminary lhcb (a) (b) s = tev data figure . (a) the b s → j /jf mass [ ] and (b) proper time [ ] distributions. the total fit is represented by a solid line, the signal distribution by a dashed line and the background distribution by a dotted line. (online version in colour.) the excellent performance of the lhcb detector is best illustrated with the wealth of physics measurements that are now emanating from the experiment. for example, the excellent knowledge of the momentum scale ( part in ) provides mass resolutions of – mev c− for b → j /jx (x represents a hadron) decay modes and the world’s best b hadron mass measurements [ ]. the resolution of the tracking system provides a proper time resolution of approximately fs and precision measurements of the b hadron lifetimes [ ]. examples of the b mass and proper time distributions are shown in figure . further illustrations of the excellent physics performance of lhcb and the tantalizing first physics results in flavour physics are given in the following section. . fruitful flavour (a) flavour production charm and bottom quarks are produced in copious amounts at the lhc. it is therefore only natural that some of the early physics measurements for the phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il flavour physics and the lhcb experiment p t of j/ψ (gev c– ) σ( χ c ) /σ (χ c ) . . . . . . . (a) (b) preliminarylhcb s = tev data s = tev m(j/ψπ ±) (mev c– ) ev en ts /( m ev c – ) preliminary lhcb lhcb pb– cs nlo nrqcd figure . the ratio of the prompt production cross sections for the cc to cc charmonium states compared with theoretical predictions (a) [ ] and the b±c → j /jp± mass distribution (b) [ ]. (online version in colour.) lhcb experiment are the study of onia (bound cc̄ and bb̄ states) and related resonances, the measurements of the fractions of the different b species and the search for new b decays, especially in the little chartered territory of the b s system. the production mechanism for onia systems at hadron colliders is not well understood and measurements from the lhc can provide invaluable new input. owing to its forward acceptance and dedicated heavy flavour trigger, lhcb has the highest sample of j /j events with the distinctive signature j /j → m+m− at the lhc. lhcb has published results on inclusive j /j production [ ], made the first observation of double j /j production at the lhc [ ] and released preliminary results on upsilon (bb̄) production [ ]. lhcb has also reported results on the production of the cc states [ ] (shown in figure a), the x ( ) [ ], the exact nature of which is still unclear, and exclusive m+m−(g) final states in low-multiplicity events [ ]. knowledge of the fractions of the different b species produced in pp collisions at the lhc is a very important input to many heavy flavour physics analyses. already with the first data, lhcb has measured the fraction of b s produced compared with b d [ ], and observed a significant b + c signal [ ] (shown in figure b), boding well for the future b+c physics programme of lhcb. (b) matter–antimatter asymmetries the asymmetry between matter and antimatter in our universe is one of the unsolved scientific mysteries. cp violation, a requirement to produce such an asymmetry, has so far been observed in the kaon and b and b+ systems (see review entitled cp-violation in meson decays in nakamura et al. [ ]). however, the magnitude of the observed effects is not sufficient to explain our matter- dominated universe. lhcb will be the first experiment to perform precise studies phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il v. gibson . (b)(a) . . – . – . – . – . – . – . – . . % % % . . . t modulo p / dms (ps) fs (rad) d g s (p s) s = tev, l = pb– . a m ix . . . . – . – . – . – . – . lhcb preliminary s = tev pb– figure . (a) the mixing asymmetry for b s signal candidates as a function of proper time modulo p/(dms ). (b) contours indicating the allowed region for fs against dgs from the preliminary lhcb analysis. only statistical uncertainties are considered but these are dominant with the present dataset. the point with the small error bar close to fs = is the sm prediction. (online version in colour.) of cp violation in the b s system and to search for new sources of cp violation in a theoretically clean environment. already with the little data accumulated in , it has been possible to discover new decay channels that will be important for future study. these include the decay channel b s → j /jf ( ) [ ] in which the final state is cp eigenstate and the gluonic–penguin-dominated decay b s → k ∗ k ∗ [ ], among others. the importance of the former channel is that it can be used, alongside the ‘golden’ decay mode, b s → j /jf, to measure the b s phase which parametrizes mixing-induced cp violation. the measurement of cp violation in the b s system is extremely important, as any significant enhancement in the cp-violating phase above the small value predicted by the sm will be a clear sign of new physics. indeed, current measurements from the tevatron experiments, cdf and dØ, show a tantalizingly small difference from the sm prediction [ , ]. the b s → j /jf analysis is an exceedingly non-trivial study, being a time-dependent angular measurement. lhcb has established the components of the analysis, validating its proper time reconstruction with measurements of b hadron lifetimes [ ], making the first studies of the untagged angular distributions in b s → j /jf and the control channel b d → j /jk ∗ [ ] and developing the flavour tagging strategy [ ]. critical to the measurement is the ability to resolve the very fast b s − b s oscillations. this has been demonstrated, as shown in figure a, by one of the world’s best measurements of the oscillation parameter dms = . ± . (stat.) ± . (syst.) ps− [ ]. lhcb has recently put all the elements of the b s → j /jf analysis together in a preliminary flavour-tagged study of the b s mixing phase, fs [ ]. the sample size is not yet sufficient to extract a value of fs itself, but contours may be drawn in the plane of fs against dgs (where dgs is the width difference between the b s mass eigenstates). the result is shown in figure b. with the integrated luminosity expected in , lhcb will be able to measure fs with a precision of about . radians and shed light on any new physics contributions. phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il flavour physics and the lhcb experiment (b)(a) . . . . . . . . . . . . . . . . . . . . k+p – invariant mass (gev c– ) ev en ts / ( . g ev c – ) k–p + invariant mass (gev c– ) s = tev data lhcb preliminary s = tev data lhcb preliminary figure . b → k p events selected in the data. the fitted signal component is the dominant dashed curve. the difference in yields between (a) k +p− and (b) k −p+ is driven by cp violation in the b decay. the other curves show the contribution of background components. (online version in colour.) a major responsibility of lhcb is to provide a solid benchmark of the sm picture of quark flavour interactions against which new physics contributions can be judged. an important aspect of this exercise is the precise determination of the ckm unitarity triangle angle g, both in tree-level decays, such as b± → dk ±, and in loop-dominated modes, such as b → p+p−. although the data sample accumulated in is too small to allow g to be measured, the foundations for this programme have already been laid with a series of studies that illustrate the potential of lhcb in hadronic final states and the power of the particle identification capabilities afforded by the rich system. studies of two-body b decays have provided the world’s best measurement of the bs → k +k − lifetime [ ] and yielded evidence for cp violation in the channel b → k p [ ], shown in figure , with a value consistent with previous measurements. with the expected integrated luminosity in and , lhcb expects to measure g with a precision of about ◦ [ ]. (c) rare b decays searching for the very rare decay mode b s → m+m− is of paramount importance in flavour physics, because the value of its branching fraction is predicted with good precision in the sm, ( . ± . ) × − , but large enhancements are possible in many variants of supersymmetry and alternative new physics models. this analysis therefore represents one of the most promising ways to look for new physics at the lhc. lhcb has recently published the results of the search for this decay based on the data collected in [ ]. no signal is yet observed, and an upper limit is placed on the branching fraction of . × − at the % confidence level, as shown in figure a. this limit is very similar to that achieved by the tevatron experiments, but is based on around two orders of magnitude less data. with the data foreseen in – , it will be possible to improve the sensitivity of the search to around the sm value of the branching fraction; the discovery potential is illustrated in figure b. this means that the lhcb experiment has the potential to discover new physics beyond the sm within the next years or to severely constrain viable new physics scenarios. phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il v. gibson . . . . . . . . . . . . . . . . . (a) (b) c l s lhcb lhcb projection from l = pb– b(bsÆmm) ( – ) s s b r ( × – ) l (fb– ) figure . (a) observed (solid curve) and expected (dashed curve) confidence levels as a function of the b s → m+m− branching fraction from the data. the shaded area contains the ± s interval of possible results compatible with the expected value when only background is observed. the % ( %) confidence level observed is indicated by the solid (dashed) line. (b) the s observation and s discovery curves as a function of integrated luminosity. (online version in colour.) . summary flavour physics now perches on the brink of potential new discoveries with the turn-on of the lhc. the lhcb experiment has made a tremendous start and is already producing world-class measurements and exploring new avenues using the many new decay modes observed. lhcb is also producing many new results not mentioned here, such as mixing and cp violation in the charm quark system and electroweak measurements using w ± and z production, which will make a very significant impact on our understanding of flavour physics, the sm and beyond. lhcb aims to collect a total integrated luminosity of fb− by , followed by an upgrade of the experiment to collect fb− per year thereafter [ ]. this will enable lhcb not only to discover and to identify new physics in flavour, but also to extend the scope of the experiment to include possibilities for interesting discoveries over a whole range of phenomena, including searches for majorana neutrinos, exotic higgs decays and precision electroweak measurements. lhcb is now at the forefront of a new era of discoveries and precision measurements in flavour physics. it is a privilege to be part of the exciting times ahead! i thank my colleagues on lhcb for all their tremendous effort in producing many beautiful first results from lhcb and as we look forward to a very fruitful future. i would also like to make a personal thank you to prof. george kalmus and the rest of the organizing committee for making this discussion meeting a very enjoyable experience. references nakamura, k. et al. (the pdg group). the review of particle physics. j. phys. g , . (doi: . / - / / a/ ) charles, j. et al. (ckmfitter group). cp violation and the ckm matrix: assessing the impact of the asymmetric b factories. eur. phys. j. c , . (doi: . /epjc/s - - ) phil. trans. r. soc. a ( ) d ow nl oa de d fr om h tt ps :/ /r oy al so ci et yp ub li sh in g. or g/ o n a pr il http://dx.doi.org/doi: . / - / / a/ http://dx.doi.org/doi: . /epjc/s - - flavour physics and the lhcb experiment lenz, a. et al. (ckmfitter group). anatomy of new physics in b − b− mixing. phys. rev. d , , (doi: . /physrevd. . ) alves, a. a. et al. (lhcb collaboration). the lhcb detector at the lhc. j. instrum. , s . (doi: . / - / / /s ) aaij, r. et al. (lhcb collaboration). measurement of s(pp → bb̄x ) at √s = tev in the forward region. phys. lett. b , – . (doi: . /j.physletb. . . ) aaij, r. et al. (lhcb collaboration). measurement of j /j production in pp collisions at√ s = tev. eur. phys. j. c , . 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the beauty of flavour the lhcb experiment fruitful flavour flavour production matter--antimatter asymmetries rare b decays summary references © blackwell publishing • journal of cosmetic dermatology , , – parting thoughts blackwell publishing inc p a r t i n g t h o u g h t s the shape of beauty: determinants of female physical attractiveness maryanne l fisher , phd & martin voracek , phd department of psychology, st. mary’s university, halifax, canada school of psychology, university of vienna, austria summary rarely has one research area gained as much attention as that which is observed for female physical attractiveness. the past decade has resulted in numerous, exciting devel- opments, particularly with respect to three proposed determinants of beauty: waist to hip ratio (whr), body mass index (bmi), and curvaceousness. the goal of our paper is to pro- vide a highly necessary review of contemporary research on the female attractiveness, including an in-depth examination of these factors. in our review, we first discuss whr, an index of fat deposition, which is calculated by measuring the circumference of the waist compared to the circumference of the hips. whr is controlled by the sex hormones, and increases as women age, and hence, may influence perceptions of attractiveness. this factor has been hotly contested, as some researchers have claimed that a whr of approximately . is universally most attractive, whereas others have found inconsistent findings, or suggest the importance of other factors, such as bmi. body mass index (bmi), calculated by dividing the body weight (in kilograms) by height (in meters) squared, serves as a measure of body fat. although whr and bmi are correlated, they lead to different conclusions, and the importance of bmi as a measure of female attractiveness is debated in the literature. similar to whr research, bmi and its role in attractiveness is not cross-culturally consistent and is affected by the availability of resources within a given environment. it may be the case that both whr and bmi influence female attractiveness. however, there has been little investigation of this possibility. we have explored this issue in our research, which revealed that both influence attractiveness, but in addition, we noticed that curvaceousness was also a factor. curvaceousness is the degree of “hourglass” shape as determined, for example, by the size of the bust, relative to the circumference of the hips and waist, and the size of the buttocks. however, curvaceousness does not appear to be temporally stable as a marker of attractiveness, and it is not consistent across modes of presentation. for example, models in male-oriented magazines are more curva- ceous than models in female-oriented magazines. in summary, faced with these recent findings, it is difficult to ascertain agreement among the various factors, especially when researchers investigate each determinant in isolation. we conclude that, although researchers have made many important initial steps in examining female attractiveness, there remains much to be discovered. keywords : body mass index, curvaceousness, physical attractiveness, waist to hip ratio correspondence: maryanne l fisher, phd, department of psychology, st. mary’s university, halifax, canada. e-mail: mlfisher@smu.ca accepted for publication october , determinants of female beauty • m l fisher & m voracek © blackwell publishing • journal of cosmetic dermatology , , – introduction compared to the many research areas, physical attractiveness has gained an inordinate amount of attention. researchers have utilized several approaches, such as attempting to isolate the various phenotypic (i.e., physical) proportions underlying beauty, , as well as the environmental causes of variation in attractiveness, the effects that attractiveness has on interpersonal relationships, variation in cross- cultural evaluations of attractiveness, and even the role of attractiveness in choosing a partner for mating. the vast majority of attractiveness research is conducted on women and how these factors relate to female beauty. furthermore, although there is a considerable history of attractiveness research, the past decade has led to many new and exciting developments, especially with respect to the physical determinants of female attractiveness. however, during this time, a complex and rather conflicting image has appeared. thus, the goal of our paper is to review the major, recent findings and derive a general conclusion on the shape of beauty. we will begin by discussing the importance of female attractiveness as compared to male attractiveness, and then proceed to discuss three primary attributes that appear to underlie beauty. the importance of female attractiveness in this review, we will be paying particular attention to female attractiveness because it has been studied to a far greater extent than male attractiveness, and seems to have a more substantial role in mating behavior in particular. this difference in research focus is not without understandable reason; men place considerably more importance on female attractiveness than women place on male attractiveness. – moreover, women pay close attention to other women’s attractiveness, relative to other traits and characteristics. thus, given the salience of female beauty, it is not surprising that it has been well studied relative to male attractiveness. this dichotomy is well captured by the sexual selection theory, which connotes that people select mates to maximize their reproductive success or, in other words, to maximize the probability that they will successfully have children. therefore, according to this theory, people prefer physical features that serve as cues of reproductive value, such as youth for women, which is based on the assumption that a young woman is presumably more fertile than an older woman. however, although both women and men prefer attractive rather than unattractive mates, the critical nature of female attractiveness has been stressed to a much larger degree because of its universal, adaptive nature. , , during humans’ long evolutionary history, women have been unable to secure their own resources, such as sufficient food and shelter, because of the demands of producing and raising offspring. hence, women are thought to prefer men who possess resources, as well as skills relating to parenting and protection of offspring. in contrast, men are believed to prefer attractive- ness in a mate beyond all other characteristics, where attractiveness is an indicator of a woman’s potential to successfully provide offspring. in fact, women even compete among themselves in terms of attractiveness, and this competition appears to be most fierce during times of heightened fertility. in one study, women in the maximally fertile phase of their ovulatory cycle, based on self-report, rated female faces significantly less attractive than women in less fertile phases. there was no corresponding effect for male faces, suggesting a unique process occurs when women judge other women. because women presumably compete for mates possessing resources and parenting ability, and to a lesser degree, attractiveness, female competition is expected to be strongest when conception is most probable. due to the critical nature of women’s beauty for winning mates, it is logical that women compete in this arena. having now established the motivation for examining female attractiveness, we are left with a remaining question – what is the actual shape of female beauty? how does an attractive female really look? there have been numerous factors proposed over the past decade. we will now present three factors that have gained much research attention and have been found to influence perceptions of female physical attractiveness: waist to hip ratio (whr), body mass index (bmi), and curvaceous- ness. in addition, we will present some less well-explored but also important issues such as the sex of the evaluator, societal influences, and the mode of presentation. waist to hip ratio one of the first factors to be empirically isolated as a determinant of female physical attractiveness was whr. whr is an index of fat deposition, calculated by dividing the circumference of the waist (at the narrowest point around the torso, under the iliac crest) by the circumference of the hips (at the greatest protrusion of the buttocks). the development of whr is controlled by the sex hormones, such that estrogen stimulates fat deposition on the hips, buttocks, and thighs whereas inhibiting fat deposition in the abdominal region. as women approach menopause, more fat is deposited around the waist, and whr increases. moreover, whr has been found to be related to hormonal effects, risk of major disease, and fertility. it was proposed that whr, which varies independently of weight, is involved in the initial stages of mating by influencing men’s decision determinants of female beauty • m l fisher & m voracek © blackwell publishing • journal of cosmetic dermatology , , – to initiate contact with women. in other words, it acts as a filter to exclude women who are unhealthy and have low reproductive capacity. some research has revealed that women and men rate, regardless of the weight or body fat, a figure with low whr (i.e., . ) as most attractive, as well as the most healthy, of higher reproductive value, , and younger. when line drawings of figures are used, there is a negative relationship between whr and attractiveness; as the whr of the drawings increased, the attractiveness ratings decreased. similar results were obtained in a study of the centerfolds and miss america beauty contestants, as a whr of . remained relatively stable over the time period that was analyzed, and among cross-cultural samples. although there have been contemporary replications of these findings, the overall conclusion remains quite contradictory. for example, in one study, underweight women were rated more attractive than normal-weight or overweight figures, and figures with a high whr (i.e., . ) were considered more attractive than figures with a low whr across all weight conditions. similarly, it has been demonstrated that waist size, hip size, and weight can be varied to produce differences in whr judgments on attractiveness, which suggests that whr is not a stable marker of attractiveness that is independent of body size. additionally, there have been several studies that fail to find cross-cultural support, as countries with limited western exposure demonstrate preferences for larger whrs. , others have noted that the original whr figures did not allow for the examination of the effects of hip versus waist size, but rather only examined the two together. in fact, when waist and hip size are individually manipulated to calculate whr, waist size has a significantly larger influence on attractiveness ratings than hip size. furthermore, the original research only included figures with whr ranging from . to , and thus, it was not possible to determine whether the often-selected . whr is optimally attractive, or whether an increased range would lead to different results. the verdict about whr as a primary indicator of attractiveness has yet to be derived, but there seems to be little agreement between it and other measures of bodily and facial attractiveness. body mass index a second factor that has been considered is that of bmi, calculated as body weight (kg) divided by height (m) squared, which serves as a measure of body fat. whr is positively related to bmi, as bmi may result in an increased or decreased whr, especially when bmi is very low or very high. however, it appears to be the case that bmi explains more variance in attractiveness than whr. , therefore, according to these results, bmi is of more importance in accounting for evaluations of attractiveness than whr. although it may be a critical indicator of attractive- ness, cross-cultural inconsistencies show that it is not stable. in cultures where women have limited economic opportunities and wealth, men consider women with high levels of body fat to be considered attractive, whereas the reverse it true for cultures that have an abundance of resources. in fact, there is a direct relationship between female obesity and socioeconomic status in resource-poor societies, and an inverse relationship between female obesity and socioeconomic status in resource-rich societies. when resources are scarce and individuals are presented with the risk of malnutrition, people tend to prefer women that are heavier (i.e., those possessing a higher degree of body fat). in contrast, faced with the risk of over-consumption in resource-rich locations, people prefer lighter women. it is curious that these trends occur only for female attractiveness and weight; there is no relationship between socioeconomic status and men’s weight, for example. these differences are apparent not only at the cultural level, but also at an individual level. men who perceive themselves as financially poor or hungry prefer heavier women than men who perceive themselves as financially successful or not hungry. these trends can be observed in the media as well; during times of difficult social and economic conditions, playboy playmates of the year were significantly heavier than during more prosperous times. the interaction of whr and bmi a handful of recent studies have shown that there are important relationships between whr and bmi, and that none, by itself, is a reliable indicator of female physical attractiveness. for example, when men were presented with nude photographs of women’s frontal view (faces obscured) and back view, as well as their faces, attractiveness was negatively correlated with bmi. however, it was not simply a matter of men declaring thin women as most attractive, as the most attractive women, according to men’s evaluations, were those with intermediate levels of body fat and whr. to further investigate this interplay of whr and bmi, we have examined the stability of these measures in playboy centerfolds over a -year period. to conduct a deeper analysis of the data, we also included measures of waist to bust ratio, bust to hip ratio, and an androgyny index, calculated as waist/hip (hip*bust)** . . all measures except weight showed temporal change, such that over time, bust and hip size decreased whereas waist size increased. furthermore, bmi and bust to hip ratio decreased, whereas whr, waist to bust ratio, and androgyny index increased. therefore, neither whr nor bmi appears to be stable over determinants of female beauty • m l fisher & m voracek © blackwell publishing • journal of cosmetic dermatology , , – time, and hence, neither appears to be a consistent marker of female physical attractiveness. in fact, over time, the models became more androgynous and less curvaceous. bodily curvaceousness our study on playboy centerfolds aptly demonstrates the necessity of discussing a third factor, curvaceousness, which appears to be central to judgments of female attractiveness. curvaceousness refers to the degree of the “hourglass shape,” such as the bust to waist ratio or enlarged breasts, buttocks, and hips combined with a slender waist. evaluations of curvaceousness in relation to attractiveness change over time, as evidenced by an analysis of body measures of models in vogue and ladies home journal between and . when a high number of women began to graduate from college or entered the american job market, the models became less curvaceous, implying that women tend to not emphasize a feminine shape when their economic prospects are posi- tive. curvaceousness may also be associated with mating strategy. curvaceous women, who are most attractive to men, can successfully marry to secure resources for offspring. women who are minimally curvaceous are not as attractive to men, and hence, must use alternative strategies, such as obtaining independent economic success. an added layer of complexity concerning perceptions of attractiveness in conjunction with curvaceousness is the sex of the person performing the evaluation. for example, if one may assume that models in popular magazines represent the pinnacle of female attractiveness, there are intriguing noteworthy differences in the model’s body shape, depending on the primary readership’s sex. that is, models in male-oriented magazines, such as playboy , tend to be more curvaceous than models in female- oriented magazines, such as vogue . women and men also have differing opinions about what is attractive with respect to body weight. it is apparent that women believe that a thinner woman is maximally attractive to men than one that men actually prefer. furthermore, it is intrigu- ing that, in addition to being sensitive about personal body weight, women are also sensitive to body shape. many women are self-conscious about the distribution of fat on their bodies, and pay special attention to excess fat located on their buttocks, hips, and thighs. even traits such as eating behavior, especially restraining one’s eating, interact with perceptions of female body shape attractiveness. further considerations: the mode of presentation if the controversies within each of the factors were to be resolved, there exists at least one issue that still requires consideration – the venue in which the woman’s attractiveness is judged. for example, an attractive woman acting in a movie does not necessarily have the same morphology as an attractive woman in a photograph. we have recently examined this issue by comparing the bodily measurements of actresses starring in adult media movies and magazines. we found that low bmi was related to frequent movie starring, wheres whr, waist to bust ratio and bust size were not. conversely, low whr, low waist to bust ratio, and larger bust size were related to frequent magazine starring, whereas bmi was not. it should be noted that we are not the first to propose that there exists a difference in attractiveness as a result of the mode of presentation. recently, it has been hypothesized that models in playboy are potentially selected on their physical attractiveness, rather than facial attractiveness, whereas mainstream movie actresses may rely more on facial attractiveness than physical attractiveness. although not directly related to our findings, it does add support to the notion of domain- specific attractiveness perception. discussion in summary, contemporary research has revealed a complex, and at times conflicting, picture of female beauty. it is apparent that many factors influence a woman’s attractiveness, including her whr, bmi, and level of curvaceousness, but how these features interact or the relative importance of each factor compared to the other is still unknown. it remains to be proven that there are stable indicators of female attractiveness, or that any attribute can withstand the tests of time and cross-culture applicability. the issue is further complicated by the use of methodology; compared to the facial attractiveness research, the state of physical attractiveness research is poor and does not appear to be quickly improving, as many researchers rely on line drawings or similar stimuli with poor ecological validity. moreover, in this review we have focused strictly on physical attractiveness, and omitted any discussion of nonphysical features that impact assessments of attractiveness. for ex- ample, simple availability positively influences evaluations, as does status, and interpersonal variables such as famili- arity and respect. after a decade’s worth of research, we are only beginning our exploration into the shape of beauty. conclusion our review of the contemporary literature reveals that determining the components of female physical attractiveness is a complex and challenging task. the three factors that have been the 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townsend jm, levy gd. effects of potential partners’ physical attractiveness and socioeconomic status on sexuality and partner selection. arch sex behav ; : – . kniffin kn, wilson ds. the effect of non-physical traits on the perception of physical attractiveness: three naturalistic studies. evol hum behav ; : – . this may be the author’s version of a work that was submitted/accepted for publication in the following source: baulch, emma ( ) longing band play at beautiful hope. international journal of cultural studies, ( ), pp. - . this file was downloaded from: https://eprints.qut.edu.au/ / c© consult author(s) regarding copyright matters this work is covered by copyright. unless the document is being made available under a creative commons licence, you must assume that re-use is limited to personal use and that permission from the copyright owner must be obtained for all other uses. if the docu- ment is available under a creative commons license (or other specified license) then refer to the licence for details of permitted re-use. it is a condition of access that users recog- nise and abide by the legal requirements associated with these rights. if you believe that this work infringes copyright please provide details by email to qut.copyright@qut.edu.au notice: please note that this document may not be the version of record (i.e. published version) of the work. author manuscript versions (as sub- mitted for peer review or as accepted for publication after peer review) can be identified by an absence of publisher branding and/or typeset appear- ance. if there is any doubt, please refer to the published source. https://doi.org/ . / https://eprints.qut.edu.au/view/person/baulch,_emma.html https://eprints.qut.edu.au/ / https://doi.org/ . / longing band play at beautiful hope emma baulch emma baulch is a research affiliate with the island southeast asia centre at the school of culture, history and language, the australian national university. email. ebaulch@gmail.com longing band play at beautiful hopei emma baulch abstract this article enquires into the contextual dimensions of indonesian consumerism by presenting the rise to national fame of provincial boy band, kangen (longing) band. the case of kangen band suggests that indonesian consumerism entails new ways of heralding the masses that rely on and play with old generic terms, kampungan (hick-ish) and ‘melayu’ (malay). it also reveals some of the specificities of the indonesian consumerist environment, in which ring back tones (rbt), pirate recordings and corporatized fandom are important resources in the formation of consumer subjectivities. keywords consumerism, mobile telephony, fans, pop genres introduction [w]hat we need to avoid is the search for pre-established sequences of institutional change, axiomatically defined as constitutive of the consumer revolution. what this might encourage is a multiplication of scenarios concerning the appearance of consumer society, in which the rest of the world will not simply be seen as repeating, or imitating, the conjunctural precedents of england or france. arjun appadurai, : in mid , i attended an on–air event for the television station sctv in a lavish housing complex called harapan indah (beautiful hope), in bekasi, on the periphery of jakarta. i was staying in well�established, leafy menteng, at the city’s heart. getting to bekasi meant a long taxi ride through the night, past the jungle of tall office buildings � the embassies, the construction and mining giants, and the multilateral aid agencies, their banks of square windows glinting like sequins. we ascended to a lonely tollway, and little could be seen but other cars speeding by. eventually, the toll road gave way to a familiar, harried scene. dusty, exhaust- stained kiosks made of plywood - a hairdresser, a street-side dentist, a grease�smeared motorbike repair shop - lined the roadside. suddenly, the scene was transformed again, as we turned onto the newly paved and palm�lined road to harapan indah. rods of laser light could be seen in the near distance, moving crazily in haphazard arcs, exterminating any fears of rain. the lights directed the gaze toward the location of the stage, which also soon came into view. it was flanked by walls of fluorescent orange and yellow led lights, advertising the event sponsor. four acts appeared on stage that night: maia duo, hijau daun, kahitna and kangen band. my mission tonight was to catch kangen band (longing band). kangen band first piqued my interest in , when i undertook a study of jakarta-based music writers. i found that, among them, the matter of kangen band’s (lack of) quality was not negotiable.. the band’s appearances on national television also elicited criticisms from several high profile composers, who considered their songs to be poorly composed (cahyono a, b).ii but the band’s producers focused on kangen band’s rise to fame despite humble beginnings as a success story to be celebrated (sujana ). it was from these promotional efforts that i first learned the producers’ narrative of kangen band’s rise to fame. this story begins around in , when a group of youths from lampung, in southern sumatra began gathering together and busking on the streets during the free time they had from their day jobs (they worked as pushcart traders and construction workers). eventually, they began staging more formal performances at music festivals in their hometown. by mid- , the collective had chosen the name kangen band and recorded a demonstration compact disc of original compositions by guitarist dodhy. in the months following, songs from the disc were broadcast in strategic public places around lampung: on the radio, on the bemo (public transport vans), in malls, and in the form of ‘unofficial’ or pirated compact discs sold by the roadside,iii at informal stalls known as emper-emperan. by , kangen band’s popularity manifested in similar form on java. in , a former print journalist, sujana, who had recently established an artist management company, positif art, ‘discovered’ kangen band and invited its members to sign with positif art and pioneer its novel strategies for pop production: these included signing a recording contract with warner music to repackage their debut album, tentang aku, kau dan dia (on me, you and him), which had previously been so widely disseminated in unofficial formats. when incorporated into the publishing and distribution systems of a major recording label, kangen band proved to be commercially successful. however, once part of such official systems of musical reproduction, kangen band also assumed a new format: originally, the group conceived of their performances in the register of pop indonesia (interview, andhika). after signing with positif art, however, kangen band became known as a pop melayu band, a label that classified kangen band as a band emerging ‘from below’,iv or from the lower classes. in the commercial production of kangen band, old generic terms melayu and kampungan were strategically employed to evoke upward mobility. a narrative of upward mobility serves as a central object in the current study of kangen band. broadly speaking, the article presents an enquiry into indonesian consumerism, and i use the narrative to trace some of the historical forces implicated in the crystallization and dissolution of particular consumer subjectivities. however, whilst the narrative of upward mobility dominated official kangen band performances, it was not the only signification. an examination of official fan practices reveals kangen band’s performances to be polysemic. further, the unofficial field in which kangen band initially circulated in purely sonic (not visual) form, regionally, via pirated recordings and radio broadcasts predated the meta-text of upward mobility. in this unofficial field, kangen band’s meaning was less certain. the article initially addresses this undetermined domain, which i characterize as ghostly, then follows with a consideration of the band’s commercial production under the auspices of warner music and positif art, which stressed visibility. in the following section, i discuss how ghostliness and visibility describe separate realms of consumption with distinct political implications. from the ghostly to the visible the roles youtube plays in contemporary cultural productions urges social researchers to tread carefully when interpreting the political implications of the consumption and production of amateur performances - in the current case, those of kangen band prior to its recruitment to major label production processes. for example, youtube makes it difficult to celebrate the capacity of amateur performances to bypass official processes as a subcultural victory. such bypassing simply attests to shifts in cultural economies enabled by digitality. here, then, the characterisation of unofficial kangen band performances as ghostly is not meant to imply that that they self-consciously resisted big capital pop musical institutions. invocation of ghostliness, rather, is an attempt to begin sketching how the kangen band phenomenon reveals cracks in the public culture and its uncanny dimensions. in such uncanny spaces, i posit, cultural performances can be loose, relatively unregulated, and quite open to interpretation. the first way in which kangen band’s unofficial performances were ghostly pertains to their wide circulation in purely sonic form. in a pirate economy awash with unofficial video recordings, this is unusual. in his book, sujana expresses frustration at the utter unavailability of any images of kangen band that may have aided him in his quest to uncover its potential. however, prior to its production by positif art and warner, the kangen band sound was already ubiquitous. songs from the debut album circulated as radio broadcasts, they pervaded malls, and they sold spectacularly at the emper- emperan. despite such ubiquity, the band remained invisible. the second dimension of kangen band’s early ghostliness pertains to the uncertain generic affiliations of its sound – an uncertainty accentuated, perhaps, by the absence of any visual cues. as i mentioned in the introduction, kangen band’s composer, dodhy, originally conceived of his compositions in the register of pop indonesia: a genre which stereotypes metropolitan, middle class culture. but the compositions on kangen band’s debut album do not display the lyrical proclivity for hip, metropolitan language or self-confident masculinity that are normally features of this genre. in fact, the songs brazenly make use of provincially inflected slang and are markedly sad and despairing, and in this sense they are excessive and wild, because they apply a typically melayu sensibility (david, ) to pop indonesia.v this rendering blurs the distinction between melayu and pop indonesia, and their attendant meta-texts of lower classness and middle classness respectively. suggests pop indonesia’s availability for subaltern ex-corporation, or poaching (jenkins, ), and unhinges the songs from the kinds of metatext generic certainty can provide. this generic unhinging is built upon by the way in which kangen band, in its early, unofficial form, manifested as a particular kind of digitally mediated social phenomenon. similar to the youtube phenomenon, digital sound reproductions enabled kangen band recordings tp spread rapidly and in great volume. youtube played a minor role in the music’s dissemination; of greater significance was the pirate economy of unofficial roadside exchanges, radio broadcasts, and sales at the emper-emperan - which, ipso facto, generated a large volume of phoned-in radio requests, and vice versa. this mode of proliferation distinguishes the techno-social dimensions of amateur kangen band performances from similar phenomena mediated by visually rich, interactive web formats such as youtube. early kangen band performances were purely sonic commodities, and enthusiasm for them was not socially networked in a web-mediated sense.vi the dialogue between radio and the emper-emperan gives rise to a more ethereal kind of network, for it neither records numbers of hits nor provides space for viewers’ comments. together with the band’s invisibility and generic uncertainty, this ethereal network yielded descriptions of the band’s songs as strangely appealing, ghostly.vii once signed to warner, however, kangen band’s ghostliness became a figment of its past. the band’s image materialized, as it appeared in music videos and on live telecast performances - much to the chagrin of a number of authoritative critics, who lambasted the band’s poor-quality compositions and unsightliness, due in part to the lead singer’s chronic acne, as evidence of the band’s inherent vulgarity (cahyono a, b). the band’s unsightly appearance was, in fact, heavily airbrushed out of the cover of their first album with warner, yang sempurna (perfection), the repackaged version of the debut album tentang aku, kau dan dia. nevertheless, although the audio tracks were remastered, little additional audio production took place. the resultant repackaged recording is imbued with a sense of under-production: instrumentation, sounds tinny, the vocals are thin, often out of tune, and wavering. warner’s repackaging, then, entailed only a partial makeover. the band was rendered visible, but the original, unofficial sound was essentially retained. this suggests, not an elimination of vulgarity, but an airbrushing and yet strategic use of it. the second way in which kangen band assumed a new form pertains to the strategic use of the terms melayu and kampungan (hick-ish/ bogan-y) in the course of the band’s promotion. as mentioned above, the band’s generic re- assignment, from pop indonesia to pop melayu, eased its official production as a narrative of upward mobility. in response to strong criticisms of the group, the band’s label capitalized upon the image of provincial vulgarity associated with the term kampungan and highlighted the members’ humble beginnings. in cinematic and literary form, narratives of the bands ‘rags-to- riches’ story began to appear in chain bookstores and on national commercial television. in , for example, the band’s manager published a book recounting its rise to fame, entitled rahasia kangen band: kisah inspiratif anak band (the secret of kangen band: the inspirational story of a pop band). tukul arwana, a successful comedian and talk show host who characterizes an ugly man of humble village origins with a wicked sense of humour, is quoted on the cover: ‘keep going forward, kangen band…just believe in yourself, like me.’ prior to this publication, in , after kangen band signed to warner music, the television station rcti aired a film that recounted their rise to fame, entitled ‘aku memang kampungan’ (proud to be a bogan/hick). both productions implicate a reclaiming of the term kampungan, normally employed as a term of derision, and suggest an attempt to herald the masses in new ways, using pop melayu as a mode of address. a brief foray into the broader field of public discourse in which this strategic use of kampungan/melayu may be located is necessary to contextualize its value for kangen band’s image production. kampungan has historically been an important theme within scholarship on indonesian popular music. such discourses dichotomize kampungan and gedongan (trans: urban?) ideals. these are terms that literally refer to the structured environment (the housing and commercial structures of the villages and slums of the city), but signify more widely as positions of centrality and marginality in relation to the metropolis, implying vulgarity in contrast to refinement.viii broadly speaking, kampungan-gedongan are said to relate variously to the two musical genres with which this article is concerned: melayu music, which ranges from dangdut (a hybrid form defined by a melayu vocal style and instrumentaion including the suling (bamboo flute) and gendang (tabla-like drum)) to pop melayu (a genre based on the iconic elements of the melayu vocal style, but which otherwise employs western instrumentation) and pop (and rock) indonesia (which refers to songs usually sung in the national tongue but which makes use of a western pop idiom). a number of writers have provided rich and varied illustrations of uses of kampungan to describe the performance and consumption of melayu forms, and point to the gedongan nuances of pop indonesia (murray, ; wallach, ; yampolsky, ). kampungan and gedongan, then - and by extension, pop indonesia and pop melayu - may be understood as distinct socio-geographical imaginaries. these imaginaries gained traction during the new order period, when a middle class sensibility crystallised, partly through invoking the masses as politically disempowered or culturally unknowing - an invocation served well by the term kampungan. in the years immediately following soeharto’s fall, similar notions of kampungan endured as they were transposed onto the scale of media consumers employed by the us firm, nielson audience measurement. this method of tracking consumption practices (?) has gained prominence in the context of the deregulated and considerably proliferated media environment over the last decade. during research on jakarta’s pop indonesia industry in , i found that, in fact, the lower reaches of the nielson scale, which tracked sales among the nation’s underclasses barely registered on the radar of jakarta-based pop music institutions, which rushed to sell their products to urban, educated youth, denoted by the categories ab. consequently, pop producers spoke of the masses as if they were a minority whose media consumption habits could only emulate those of the well-to-do. in recent years, however, the social function of kampungan has begun to shift, and the kangen band phenomenon may be seen as a watershed moment signifying this. jakarta-based pop indonesia producers have begun to herald and address, rather than ignore the masses, and now attempt to interpolate their ‘specialness’ as a distinct public with certain tastes and life trajectories. new means to appeal to the masses coincide with the acknowledment of lower classes as pop music target markets of undeniable importance. in a time in which the recording industry is suffering a crisis globally (due to plummeting sales, largely resulting from the availability of free digital downloads), those indonesian masses residing in the nation’s peripheries, beyond the metropolis, have emerged as astoundingly enthusiastic consumers of pop music in the a new recording format that now accounts for the greatest profits (solihun, ): ring back tones (rbt). this format delivers music in the form of pre-selected song segments to mobile phones for a weekly or monthly fee. the song segment then replaces the ringtone a caller would hear while waiting to connect. the work of producing music for a profit, therefore, to a large extent requires heralding those masses who, according to the regimes of audience measurement that exist, buy most of it. histories and genealogies in the chapter of modernity at large from which the epigraph opening this article is drawn, appadurai conceptualizes logics of consumption as overlapping both local particularities and various world communications processes ( : ). much of that chapter is devoted to developing conceptual tools that might allow us to capture such criss-crossings in any study of consumerism. to this aim, appadurai distinguishes between history, which ‘leads you outward, to link patterns of changes to increasingly larger universes of interaction’, and genealogy, which ‘leads you inward, toward cultural dispositions and styles that might be stubbornly embedded in both local institutions and the history of the local habitus’ (appadurai, : ). appadurai posits a simultaneous exploration, a ‘double historicizing’. in the current study of the particularities of indonesian consumerism, it is productive to doubly historicise kangen band in the manner appadurai suggests. when we do so, we find that the marking of indonesian pop as distinctively local (either indonesia or melayu) is both infused with globally circulating ideas and linked to more situated histories of capitalism. the use of kangen band to address the ‘masses’ (segment c and below, according to the nelson scale) may be seen to have both a history and a complex genealogy. drawing an historical line, we might compare it with jing wang’s observations of china, where beijing-based advertising executives consider outlying provincial cities (segment c and below) to be the most lucrative markets (wang, : ). but an analysis oriented toward genealogy would pay special attention to how the depiction of kangen band’s upward mobility links to mythologies of the metropolis and its others (gedongan and kampungan) that predate the rise in nielson audience measurement’s importance within the indonesian media environment. the historical line suggests a view of the masses that is coterminous with the view from the suites of advertising executives worldwide. the genealogical line suggests changes in the ways kampungan-gedongan play out in the realm of pop. such changes may well be expected in a context in which the masses are reasserting their political rights, following the fall of the new order in . however, this cannot be solely attributed to the post-authoritarian polity. kangen band’s performance of upward mobility, in particular, implicates new systems for generating value from pop, only tangentially related to regime change. these new systems are more directly due to the explosive uptake of mobile telephony among the masses (heryanto, : ). this new telecommunications consumer trend is tightly intertwined with kangen band’s significance for heralding the masses. through its journey to the centre of pop production, kangen band was employed as a narrative meant to herald the masses, - a generously imaged narrative with national reach. the masses were imagined, by virtue of global audience measurement regimes, as important target markets for new musical products exchanged via mobile phone. they were depicted as avid consumers, and upwardly mobile. in authoritative, critical assessments, the kangen band phenomenon correlated with the increasing popularity of rbts as a primary profit source within pop music markets. in my interviews with them, rolling stone journalists derisively described kangen band as the ‘champion of the ring back tone’ (baulch, : ). for these critics rbts signify vulgarity. here, though, i propose a slightly different reading: the appearance of ring back tones as the primary medium for exchanging kangen band’s songs signals a move from away from the ghostly to the identifiable, with important implications for consumer agency. i have suggested above that kangen band’s self-released debut album spontaneously bubbled up through the cracks in public culture, and that this bubbling up sheds light on its uncanny dimensions both ethereal and uncertain. these qualities may be seen to emerge when cultural novelties are not yet hinged to meta-narratives. alternatively, rbts offer relatively fixed narratives: these preselected, -second song segments are issued for a monthly fee; and because they are coded and locked, they cannot be pirated. ring back tones (more accurately known as nada sambung pribadi – personalized connecting tones – in indonesian) are unlike standard ringtones - familiar beeps and crackles issued into the public soundscape. they can only be heard in lieu of the standard ring tone when callers connect to the corresponding number. for example, by purchasing a ring back tone of the kangen band composition ‘selingkuh’, subscriber ensure that callers, when connecting with their number, will hear the segment of the song, in this case including the following lyrics: pacarku, mengertilah aku/sperti aku ngertikan mu [my darling, please understand me/ the way i understand you] in this way, ring back tones function as a pre-made intimate whisper; a kind of prosthetic voice, and this instance of voicing may be contrasted with the relative looseness and openness of kangen band’s early appeal. this departure from the band’s earlier ghostliness becomes clearer when we consider the ring back tone’s reliance upon televisual mediation and, by extension, on generic certainty: in much the same way as sales at the emper- emperan conversed with radio broadcasts during the early part of kangen band’s career, ring back tone sales are dependent upon television commercialisation. national-level, advertising-funded television is the primary medium for the official pop melayu performances by which ring back tones are promoted. televised performances feature banner advertisements listing the ring back tone code numbers to the corresponding song. when official kangen band performances are viewed in this light, as part of a system in which ring back tones, television and generic certainty are mutually reliant, the transition from the ghostly to the visible becomes apparent. this is not to suggest, however, that kangen band’s official meanings are irrevocably fixed. as mentioned in the introduction, fans’ consumption practices reveal official performances’ inherent polysemy. we might obtain further insights into the dynamics of consumer agency in the production and consumption of kangen band, then, by turning to an examination of its official fan organisation, doy community. for reasons already thoroughly documented in the rich scholarship on the subject, fans are an object of interest to media scholars because they may develop intense relationships with their texts and performances of choice. scholarship on fandom has extended the question of how readers engage texts or other communications media, and this subject has preoccupied cultural studies of media since the early s. i have outlined above how jakarta-produced kangen band performances generated a certain meta-text - a narrative of upward mobility. how, then, do fans engage this narrative, and bear the meanings of sub-alternity that are thrust upon them? ‘come on auntie, we’re on!’ as mentioned above, music critics at the indonesian licensee of the authoritative rolling stone magazine unanimously derided kangen band: they viewed kangen band’s visual manifestation as substandard, and the band’s provincial origins and rise to fame via unofficial, unpolished recordings as evidence of their vulgarity. this assessment of kangen band - and its similar articulation in print media - correspond to a cultural politics that favours the urban, masculine and the tertiary-educated, developed throughout the new order (see baulch, ). the social position of the doy members i encountered in , however, contrasts with that of the music critics: many fans were female high school graduates working in various retail outlets, on the fringes of the capital city, whose socio-economic positioning differs greatly from those of educated writers at a national entertainment magazine. unlike fans communities analysed elsewhere (jenkins, ), doy community’s engagements with kangen band are not mediated by print fanzines or the world wide web, both comparatively rich in possibilities to contest or augment the original text. rather, they are mediated by two other, perhaps more imposing, institutions: the band’s management company, positif art and television. in indonesia, an official fan club is part and parcel for pop music production, and all the fan clubs i have encountered have been officially established by a band’s management or production company and are supervised and funded by the band’s management team - which in some cases is assigned by the band’s recording label. in fact, this corporatized style of fandom is not unique to indonesia, but may be thought of as one facet of a universally manifesting media convergence: the blurring of production and consumption. in a related context, henry jenkins contends in an interview with matt hill that the world wide web facilitates direct dialogues between producers and fans, thus complicating a clear distinction between them. deuze and banks characterise this particular aspect of media convergence as the rise of co-creative labour, in which “practices of user-created content and user-led innovation are now significant sources of both economic and cultural value” (deuze and banks, : ). emerging co-creative relations, they contend, prompt new queries about agency and identity. the corporatised dimensions of doyix – it was established, as are most pop music fan groups in indonesia, as a standard practice of the group’s official production - may be understood in the context of this ‘historical’ (ie, transnationally manifesting) phenomenon, as co-creative labour. however, variance most assuredly exists between one locale and the next, with regards to the the structures in which such fan groups proceed. in such structures, some ‘genealogical’ features of consumerism may be found; features that more powerfully shape questions of agency and identity than the generalised context of co-creation. since the band’s production company and television, rather than fanzines and the world wide web defined the contours of fan consumption and relationships, an examination of the televised event at harapan indah will help elucidate the nature of doy community. i arrived at harapan indah to commence my research into kangen band fandom in a taxi. the taxi dropped me off at the periphery of the audience space, where the stage was barely visible in the distance. i then ploughed through a thick wall of onlookers to reach an opening in a cyclone fence, guarded by the usual meagre-framed security. i was allowed to pass, and i soon made my way to the kangen band tent, backstage. a couple of band members were seated before brightly lit mirrors having their make-up applied. andhika, the vocalist, was standing in the middle of the tent, surrounded by personnel from an infotainment show. one show host was interviewing him, or rather, requesting that he recount the narrative of upward mobility in a single utterance. ‘pendidikan akhir sampai mana?’ (‘what level did you reach at school?’) she asked him, to which the rather wild young man acquiescently replied: ‘smp’ (‘junior high’). the show that night proceeded in a relay of single song performances by featured acts, so kangen band was ascending to and descending from the stage in four-act intervals. this was no place or opportunity to conduct an interview, i quickly realised, and i trudged off to watch kangen band’s first song performance from the side of the stage, just inside the cyclone fencing. from my safe enclosure, i observed a chaotic scene on the other side of the fence: the weight of a dense crowd pressed young boys’ cheeks hard against the fence’s metal patterning. periodically, giant water jets appeared from somewhere on high, and the crowd was sternly hosed down. overhead, television cameras on booms rooted to trusses, like prehistoric creatures with impossibly long necks, swooped down on the stage and crowd, hunting for shots. my side of the fence was also packed with people, but nothing close to the suffocating proximity of bodies observable on the other side. these people, i later realised, were the members of the fan clubs of those acts performing that night. when i encountered the members of doy community at the lip of the stage, i was surprised by the number and type of women fans. they contrasted to the wildly gesticulating, grinning female pop consumers i had observed on the morning television shows devoted to live-to-air pop performances. in the flesh, the public presence of these young women was compelling. i was reminded of my research experiences at live shows in the late- s, among underground musicians and audiences who were overwhelmingly male. today, the public sphere is generally more feminised - a result of a boom in advertising for a female audience resulting from proliferation of media. the group of fans i met at harapan indah had been led there by the head of doy’s kerawang chapter, a minuscule young working woman called uci. whilst kangen band’s many performances in small provincial cities are not likely to be televised, among doy members of the jakarta region, performances of exuberance at televised shows is precisely what positif art hopes of them (interview, sujana). doy members’ compliance with this hope is therefore of note, and may be thought of as an illustration of successful disciplining. moreover, if uci’s way of inviting me to participate is any indication, doy members do more than simply comply. they view these moments of performing exuberance for television cameras as central to the practice of fandom. when kangen band struck up and the cameras dipped and dived overhead, uci beckoned to me and shouted: ‘ayo tante, kita harus eksis!’ (‘come on, auntie, we’re on!’) the presence of television cameras directly impacts kangen band fandom: firstly, it distinguishes doy’s consumption practices from the more ghostly contours of kangen band’s earlier unofficial circulation - it turns kangen band into something spectacular. secondly, it points to how kangen band’s shift to spectacularity generates new kinds of subjectivities among fan viewers, who develop a sense of being witnessed, in addition to witnessing (‘kita harus eksis’ !) finally, it suggests the co-laboring of fandom: doy members are not permitted only to take pleasure in the spectacle; spectacularity is expected of them as well. it is through television, in other words, that co-creative labour, which suggests complicity and consensus, is achieved. television incorporates and intertwines positif arts’ expectation of the fans with the fans’ self-perceptions - their sense of self. this assessment may uncover some implications of this co-creative labour for fan identity. however, it does not directly address the question of agency: what does co-creative labouring for spectacularity mean to the fans, and what does it suggest of their relationship to the meta-text (of upward mobility) under consideration here? each time i asked doy members what initially appealed to them about kangen band, i received a reply that regurgitated the narrative of upward mobility: ‘mereka dari bawah’ (‘they came from below’). the fans’ repetition of the metatext seems strange when we consider that most fans encountered kangen band prior to its repackaging under the auspices of warner music and positif art, and therefore only became aware of the narrative of upward mobility after their initial interest. it could not really have been the reason for their initial attraction to kangen band. had they become so identified with positif art that they not only laboured for kangen band’s televisual spectacularity, but also trotted out at will the tagline it had devised for the band? what does this instance of co-creative labour suggest of agency? this question may be considered through a discussion of some other dimensions of kangen band fandom, which extend beyond the televisual spectacular. upon our meeting at harapan indah, doy members immediately invited me to come the next day to their base camp at andika’s home in cibubur. the base camp’s significance was raised frequently when i asked fans what had prompted them to join doy. one day, uci sent me a text message to inform me of a kangen band performance on derings, one of the many live-to-air morning television shows that feature pop performances, and suggested i might like to attend. when i replied that i could not, she seemed especially keen for me to join the fans after the show in the trek to andhika’s house at cibubur. this territorial aspect of kangen band fandom is intriguing because it takes place outside the official structure of fandom that privileges televisual spectacularity. of further interest is the link doy members draw between this territorial aspect and andhika’s good moral character: uci attempted to relate this good moral character to me by referring to the fact that he sits on the floor and shares meals with the fans who hang around his house. she contrasted his sociability with the primary reason she joined doy, after resigned from pop indonesia band peterpan’s fan group: fans rarely came into contact with band members of this group. of particular note is the way in which she contrasted her descriptions of andhika’s demeanor as ‘baik’ (good) with the aesthetic values attributed by media structures that privilege the spectacular. above, i have briefly discussed how doy members are inextricably entwined with these structures; yet, uci offered the following comparison (interview, uci): i used to be a member of peterpan and ungu fan clubs, but we could never get to meet the band members! kangen band are more humble and closer to their fans. they invite us to eat with them, invite us to their house. so when we hear people saying awful things about andhika - that he is ugly - we respond that at least he is a good person, and humble. the stress doy members place on andhika’s good moral character resists two powerful narratives. firstly, it directly rejects the authoritative critics’ derision of kangen band. secondly, it creates a tangential narrative to that of upward mobility, suggesting that he has maintained his humility. however, not all would agree that the band members have maintained a commitment to their humble roots: in a conversation with me, kangen band’s manager, sujana, complained that dodhy, the band’s composer, had begun hawking his compositions to new, upcoming bands without asking sujana’s permission first. sujana explained dodhy’s antics as a case of a ‘kacang yang (?) lupa kulitnya’ (a peanut who has forgotten it’s shell) (interview, sujana). in order to stress andhika’s good moral character, evidenced by his socialisation with fans, fans employed the same metaphor, but in the negative: andhika is like a ‘kacang tidak lupa sama kulitnya’ (a peanut who has not forgotten its skin). doy members and sujana offer two very different characterisations of kangen band’s personnel - and the primary reason for their rise to fame. in sujana’s view, he is key to kangen band’s success. in the doy members’ view, sujana does not feature at all. it is they who provide the support that contributes directly to kangen band’s success. in pop artist fandom, we find a political impetus for fan commitment that exists tangentially to the corporate structures that would guide fan behaviour. this is confrimed by uci’s coments on her tasks as organiser of the kerawang chapter of doy. she was responsible for rallying members to attend live shows, as instructed by positif art. she also encouraged doy members to perform audiencehood for television cameras. i was intrigued, however, by an alternative fan persona revealed by her use of the word ‘berantem’ (to fight) to describe her encounters with security guards who guard the space below the lip of the stage, walled by the cyclone fencing separating backstage pass- holders and the massive crowd on the other side. surely she did not mean to say that she came to blows with these guards, but her use of the term ‘berantem’ is suggestive of an aggressive physicality, which she described as one of her most pressing responsibilities. at live shows, it is her job to ensure that all the kangen band fans club members are allowed to advance to the lip of the stage. she must represent their interests, and ensure that they are not disappointed. it is these interests that so often brought her into confrontation with the guards, a rubbing-up against authority that uci recounted with glee. the aforementioned dimensions of fandom shed light on the matter of agency within kangen band fans’ labour: firstly, doy’s territorial orientation and its aggressive physicality not only exist outside the official structures of fandom, but they are suggestive of a visceral sensibility that runs counter to the televisual sublime. secondly, fans’ faith in andhika’s good moral character not only rejects authoritative critics’ assessments of the band’s quality, but also appears to be premised on an interpretation of the narrative of upward mobility that is at odds with that endorsed by sujana. this act of reading may be productively compared to jenkins’ account of how star trek fans fans stretch and augment original texts, but are limited in their capacity to do so by certain constraining elements within it. at first glance, we might understand the narrative of upward mobility in this light: it worked on the fans as a constraining element, limiting their capacity to stretch and augment the text. however, doy’s territorial orientation and its stress on andhika’s good moral character reveals a resistant reading that accords considerable power to the doy members, and suggests that the narrative of upward mobility was not constraining after all, but rather empowering, and replete with agency. conclusion an aspect of mass mediated consumption a number of writers, including appadurai ( : ) have noted, and that resonated within the context of indonesian consumerism, is that it contains the possibility of both novelty and repetition.x to consume, then, is not just to bathe in a pool of desire; the pleasure of consuming can be found in the to and fro of embodiment and self�abstraction - the unique self and the mass public, the micro� and the macro�narratives. writing of advertising in india, for example, william mazzarella contends that commodities are seductive not just because they suppress ‘embodied idiosyncrasies’; commodification needs ‘the tangibility of objects and people… to lend credibility to its abstract claims’ ( : ). in a similar vein, michael warner suggests that mass�(mediated) subjectivity might be understood as an interchange between ‘embodiment and self� abstraction’ ( : ). the case of kangen band illustrates two characterisations of commodification. official fandom, a particularly intense mode of consuming commodities, manifests as both a bathing in the televisual sublime and an urge for a more visceral sensibility, as implied in uci’s use of the term berantem (to fight) to describe her relationships with the security guards at live television performances. ring back tones may also facilitate a dialogue between embodiment and self abstraction: they are not just ephemeral commodities; they are also micro�narratives (song segments) that twirl around the macro�narrative of upward mobility (as written in to the myth of the masses that the technology signifies). furthermore, they are somewhat privatized; they only ‘speak’ in the intimate (relatively speaking), one-way register of an attempted telephone connection, and are in this way a form of embodiment, a kind of prosthetic voice. they are regulated, though, by both audience measurement, a globally circulating ideology, and a more genealogical macronarrative that recounts shifts in the relation between kampungan and gedongan. hence, ring back tones are micro-narratives that twirl around macro�narratives. within a discussion of the possibility for improvisation in acts of consumption, questions about the processes by which these micro�narratives are authored and authorised, and the extent of their manipulability, are critical.  endnotes i the research on which this article is based was part of a project entitled middle classes, new media and indie networks in post authoritarian indonesia, on which ariel heryanto was lead investigator, and which was funded by the australian research council. thanks to julian millie, rebekah moore, keith foulcher and an anonymous reviewer for critical input. any shortcomings and omissions are my own. ii among those who publicly denounced kangen band were: composer erwin gutawa and musician ridho hafiedz of slank (cahyono, a, b), musicians giring ganesha, vocalist of nidji and david bayu danangjaya, vocalist of naif (http://music.detikhot.com/read/ / / / / / /david�naif�kangen� bandplease�deh). among elite critics, denunciations were controversial. composer yovie widianto (sulaksono, ); and former manager of superman is dead, rudolf dethu (suicide glam mailing list, june , ) judged kangen band’s original compositions superior to other pop indonesia bands’ plagiarisms iii kangen band members drew no financial reward from such airplay and roadside exchanges. but, in contrast to the official condemnations of piracy, which paint this practice as undermining musicians’ interests, kangen band members recall this time with great enthusiasm; it led to their well-documented rise to national prominence (sujana, ). i prefer the terms ‘official’ and ‘unofficial’ over ‘legal’ and ‘pirated’. ‘pirated’ implies theft, but members of kangen band did not take issue with the widespread reproduction and exchange of their performances at the level of the emper-emperan. iv see weintraub ( b) for a discussion of the plural, shifting meaning of melayu in popular music between - . of note in the context of this paper is melayu’s ‘eastern’ connotations and its close relation to dangdut, a stereotypically lower class form (weintraub, a), while pop indonesia gestures toward an anglo-american core (yampolsky ). v this rendering suggests pop indonesia’s availability for (provincial) subaltern excorporation. such availability may be seen to result from pop indonesia’s expanded presence in the public sphere, resulting in its dispersal. just as televisual and telephonic mediation has become central to the exchange of pop since the late- s, pop indonesia has begun to break out of its assignation as a gedongan realm, the realm of the metropolis and western derivation. for young people all over the archipelago, pop indonesia is more and more part of the mundane, its ties to an ‘originary’ euroamerica has been rendered fragile, and it has become more available for interpretation by subaltern youth in peripheral areas. vi it is not that the unofficial kangen band was absent from the web, but this was not the primary medium of its circulation. vii as revealed in discussions with fans during field work, viii a precise translation of kampungan is elusive. kampung evokes the masses’ ephemeral urban dwellings and their rural homelands. such imprecision has the effect of relegating all but a gedongan centre to marginal status. ix doy is used when referring to one’s sweetheart in the third person x pierre bourdieu’s term, “regulated improvisations of the habitus”, appadurai contends ( : � ), aptly describes the paradox of consumption. books and articles appadurai a ( ) modernity at large: the cultural dimensions of globalization minneapolis: university of minnesota press. baulch e ( ) music for the pria dewasa: changes and continuities in class and pop music genres. journal of indonesian social sciences and humanities vol. : - cahyono a ( a) erwin gutawa anggap pop melayu ‘jadul’. available at: http://artis.inilah.com/berita/ / / / /erwin-gutawa-anggap-pop- melayu-jadul/ ( may, accessed august ) cahyono a ( b) ridho 'slank' malu musik melayu. available at: http://artis.inilah.com/berita/ / / / /ridho-slank-malu-musik- melayu/ may, accessed august david b ( ). the erotics of loss: some remarks on the pleasure of dancing to sad dangdut songs. in: pop music in southeast asia’, leiden, the netherlands, – december deuze m and banks j ( ) co-creative labour. international journal of cultural studies ( ): - heryanto a ( ) entertainment, domestication and dispersal: street politics as popular culture. in: (eds) aspinall e and mietzner m (eds) problems of democratisation in indonesia: elections, institutions and society. singapore: iseas publishin,. pp. – . jenkins, h ( ) textual poachers. new york: routledge. mazzarella w ( ) shoveling smoke: advertising and globalization in contemporary india. durham and london: duke university press. murray a . kampung culture and radical chic in jakarta. review of indonesian and malayan affairs, ( ): - solihun s ( ) nada sambung bawa untung. rolling stone : - sujana ( ) rahasia kangen band: kisah inspiratif anak band. jakarta: rm books sulaksono s ( ) rancu antara melayu dan pop. jawa pos, april, wallach j ( ) exploring class, nation and xenocentrism in indonesian cassette outlets. indonesia : – . wang j ( ) brand new china:advertising, media and commercial culture. cambridge and london: harvard university press. warner m ( ) publics and counterpublics. new york: zone books weintraub a ( a) dangdut stories: a social and musical history of indonesia’s most popular music. new york: oxford university press weintraub a ( b) music and malayness: orkes melayu in indonesia, � . archipel : � yampolsky p ( ) hati yang luka: an indonesian hit. indonesia, : – . interviews andhika, vocalist, kangen band april sujana, manager kangen band, april uci, organiser for kerawang chapter of kangen band fans club, april ricky siahaan, associate editor, rolling stone, october music kangen band ( )yang sempurna (tentang aku, kau dan dia repackaged), warner music kangen band, bintang hari, warner music indonesia, ‘terbang bersamaku’, dodhy kangen websites http://music.detikhot.com/read/ / / / / / /david�naif� kangen�bandplease�deh (accessed august )  il lu s t r a t io n b y t h e p r o je c t t w in s manufacturers are ditching equation editors in word-processing software in favour of the latex typesetting language. here’s how to get started. craft beautiful equations in word with latex b y d a v i d m a t t h e w s latex or word? for physicists and math-ematicians, the choice is obvious. but for scientists in other fields the merits of latex have largely gone unnoticed. the open-source software system — used to create and precisely format scientific man- uscripts — is more akin to coding than writ- ing. since its development in , latex has become popular in disciplines such as math- ematics, physics and computer science. proponents embrace latex because of the total control it offers for document layout, or because it represents a blow to commercial software developers, particularly microsoft. others regard the software as too complicated for all but the most demanding of tasks. a study (m. knauff & j. nejasmic plos one , e ; ) that asked scientists from different fields to put both microsoft word and latex to the test ended up being one of the ten most discussed papers online the following year, according to data-science company altmetric (altmetric is owned by digital science, a firm operated by the holtzbrinck publishing group, which has a share in nature’s publisher, springer nature). the article has been viewed more than , times so far. over the past few years however, the line between the tools has blurred. in , micro- soft made it possible to use latex’s equation- writing syntax directly in word, and last year it scrapped word’s own equation editor. other text editors also support elements of latex, allowing newcomers to use as much or as little of the language as they like. “for me, latex is the tool when i want to get the typesetting just so,” says casey greene, a bio- informatician at the university of pennsylvania in philadelphia. “word is when ‘good enough’ is ok and/or i’m working with folks who need to use it.” coding equations unlike ‘what you see is what you get’ text editors such as word, libreoffice and openoffice, writing in latex is like program- ming. plain text is wrapped inside commands that describe its formatting (for example, for italics, \textit{text}; and for bold, \textbf{text}), and tables are built cell by cell. this source code is then compiled into a sleek-looking pdf, ready to read. equations are seen as latex’s strong suit (see ‘writing equations in latex’). the lan- guage boasts a vast library of shortcuts to dis- play mathematical symbols. (the version of the comprehensive latex symbol list includes some , symbols.) “one of j u n e | v o l | n a t u r e | toolbox © springer nature limited. all rights reserved. the reasons i started using latex was that i can format equations easily that look beauti- ful,” says john paul minda, a psychologist at western university in london, canada. indeed, equations were the only feature in which latex outperformed word in the study that compared the two tools. when it came to text and tables, word proved faster and users were less prone to making errors, although latex users “more often report enjoying using their respective software”, the authors noted. even latex critics such as daniel alling- ton, a computational social scientist at king’s college london who has inveighed on his blog against what he calls ‘latex fetish’, acknowl- edges that it handles equations better than alternatives. but, allington points out, scientists today can use latex’s equation syntax without aban- doning what-you-see-is-what-you-get editors. for example, allington uses the online tool mathjax. he inserts a few lines of latex code into a web form — no installation is required — and mathjax renders equations in a web page. word users can also write directly in latex syntax, and then click to convert it into a for- matted equation. microsoft says that “most” latex expressions are supported, although its website lists keywords that are not (such as \degree, the degree symbol). for google docs users, the auto-latex add-on can turn latex equations into embedded images. katie lotterhos, a marine and environmental scientist at northeastern university in boston, says this combina- tion of tools works particularly well for her, because most of her collaborators do not know how to use the typesetting language. the downside, she says, is that the software inserts the equation into the document as an image, “which is fine for peer review, but unpopular for typesetters”. similarly, users of libreoffice, a free alter- native to word, can code equations with an extension called texmaths, which converts latex syntax into a png or svg image. mastering latex users hoping to dive into latex can install a latex software bundle, such as miktex for windows, mactex for mac os, or tex live for linux. all are free to download and use, and include tools for compiling latex ‘source code’ into a pdf. word costs from us$ . a month per user as part of the broader office software suite, although a microsoft spokes- person says that the company does offer free access to the online version of word for researchers based at some institutions. such software bun- dles open the door to authoring entire pdf documents in latex. d o i n g s o a l l o w s researchers to gain “real control” over how a document looks, says philip judge, a latex advocate and an astronomer at the high altitude observatory in boulder, colorado. for laura fortunato, an evolutionary anthro- pologist at the university of oxford, uk, it was the “unreliability” of word processors — their tendency to do something “random” when “you know you’ve done nothing wrong” — that prompted her to learn latex during her phd. but the process can feel cumbersome. “the main drawback to latex for me was in constantly having to compile the text to see how it looked, and then getting errors you have to spend time tracking down,” says shannon nicley, a diamond-growth researcher, also at oxford. for nicley, the solution to that problem was overleaf, a browser-based editor for collaboratively authoring scientific docu- ments. (overleaf is also owned by digital sci- ence.) overleaf displays the article source code and a live pdf rendering side by side, mean- ing users can quickly see how their changes translate into the finished product. the tool is free for individual users, but costs from $ a month to add features such as collaboration and the ability to sync with code-sharing site github. so is latex worth mastering? it depends on the researcher: how often do you use equa- tions, how much fine-grained control do you need over a document, and how much time do you have to devote to learning a new language? basic document creation in latex is rela- tively straightforward. but creating tables is not. unlike in word, these cannot be drawn and placed on the page, but must be pro- grammed in, dimension by dimension. in the study, even latex experts made more mistakes in generating tables, and wrote less text, than did word novices over a -min- ute test period. “making tables in latex is extremely daunting, even if you have done it dozens of times before,” says nicley. “it is con- siderably faster for me to open a new excel sheet, type out the basics of a table, then copy and paste it directly into word, where i can fine tune the appearance and content.” latex is not the only programming-like option for document formatting. allington often uses markdown, which he describes as more “lightweight” than latex, because the formatting commands are more straightfor- ward. in markdown, says anthony gitter, a computational biologist at the university of wisconsin–madison, there is “very little technical syntax for contributors to break”. this was one of the reasons that gitter, and colleagues including greene at pennsylva- nia, used markdown to write an open review of deep learning in biology and medicine. in latex, there is a greater risk that contributors will make changes that prevent the code com- piling into a pdf, he warns. that said, some journals and conferences don’t accept documents in markdown for- mat, says dmitry fedyanin, a researcher at the moscow institute of physics and technology. nature, for example, prefers submissions in word, as the journal’s typesetting system requires this format, says simon gribbin, nature’s managing production editor. still, around one in ten accepted submissions are in latex format; these are converted to word before being passed to copy-editors, he says. but at nature physics, which covers disci- plines in which latex use is widespread, the editors are more flexible about document for- matting. “latex is just something that physi- cists ‘do’,” explains chief editor andrea taroni. “trying to get them to do otherwise is like trying to herd cats.” ■ david matthews is a freelance writer based in berlin. producing einstein’s famous equation in latex is almost as simple as writing e = mc^ . the only formatting there is the caret (^), which indicates a superscript. but to display equations in latex properly, you need to wrap the content in a command. square brackets and a backslash (\[e = mc^ \]) centres the equation on its own line, whereas wrapping an equation in dollar signs ($e = mc^ $) positions it in-line, in the body of the text. latex documents typically include directives at the top that describe the document’s size (a paper, for example) and formatting. for mathematical commands to work, users must instruct the software to use a mathematics package, several of which are available. the comprehensive tex archive network hosts more than , packages, allowing latex users to use everything from elvish scripts from the mind of author j. r. r. tolkien to mongolian, and typesetting styles that mimic those of newspapers. for more-complicated equations, users need to learn the syntax of the command they want to deploy. fractions, for example, are created by entering \frac{numerator} {denominator}, whereas integrals over the range [a,b] are expressed as \int_{a}^{b}. thus the integral over the range [ , ] for x + ( / p)x, would be written as \int_ { }^{ } x^ + \frac{ }{ \pi}x dx. the browser-based editor overleaf provides an overview of latex equation formatting at go.nature.com/ eh daz. d.m. writing equations in latex “one of the reasons i started using latex was that i can format equations easily that look beautiful.” | n a t u r e | v o l | j u n e toolbox © springer nature limited. all rights reserved. - ( ) - .fm j appl biol chem ( ) ( ), − https://doi.org/ . /jabc. . online issn - print issn - article: bioactive materials beauty food activities of polygala japonica houtt. ye-jin kim · beom-su park · so-young son · ja-young yun · young-je cho 영신초(polygala japonica houtt.)의 미용 식품 활성 김예진 · 박범수 · 손소영 · 윤자영 · 조영제 received: december / accepted: february / published online: march © the korean society for applied biological chemistry abstract the objective of this study was to identify beauty food activity of polygala japonica houtt., which were widely used as a folk medicinal plant to treat inflammatory diseases. both hot water and % ethanol extract of p. japonica houtt. were evaluated for their anti-oxidant, whitening, anti-wrinkle and anti- inflammatory effect based on their phenolic concentration. to measure anti-oxidant activity, four experiments were carried out. , -diphenyl- -picrylhydrazyl, , -azinobis ( -ethylbenzothia- zoline- -sulfonic acid) and thiobarbituric acid reactive substances all showed more than % efficacy in both hot water and % ethanol extract of p. japonica houtt. and likewise antioxidant protection factor value more than . to investigate the whitening effect of p. japonica houtt., the inhibition effect of tyrosinase on hot water and % ethanol extract was inhibited by . and . %, respectively. to examine the anti-wrinkle effect, the inhibition effect of elastase and collagenase on hot water and % ethanol extract were inhibited by . , . % and . , . % respectively. to investigate the anti-inflammatory effect and moisturizing effect by hyaluronidase inhibitory effect, hot water and % ethanol extract were . and . %, respectively. the result of all the above experiments show values at a concentration of µg/ml, and based on these experimental results, p. japonica houtt. can be expected as a functional material in beauty foods. keywords anti-inflammatory · anti-oxidant · anti-wrinkle · polygala japonica houtt. · whitening 서 론 영신초(polygala japonica houtt.)는 원지과(polygalaceae)에 속 하는 여러해살이 풀인 애기풀의 잎과 줄기를 말린 것을 말하며, 우리나라 전국 각지의 해가 잘 드는 산기슭 및 언덕에서 자란 다. 가는 여러 대가 모여 단단한 줄기는 그 높이가 cm 정도 이며, 잎은 타원형으로 길이가 cm로 줄기와 더불어 잔털이 있 다. 연한 자주색의 꽃은 줄기 상부에서 - 월경에 피고, 꽃받침 잎은 장이지만 양 쪽의 두 장은 날개처럼 생겨 나비와 같은 형상을 가진다(lim과 do ). 영신초는 예로부터 천식을 억 제하고 지혈작용이 있으며, 정신을 안정시키는 효과가 있다고 알려져 있다. 또한, 민간에서는 술에 넣어 매일 규칙적으로 복 용하면 골수염, 골관절 결핵 등을 치료하는데 사용되었다고 알 려져 있다(wang 등, ). 최근 심장병, 면역질환, 암 등과 같 은 성인병 발병 원인이 활성산소로 인한 세포의 손상이라는 연 구들이 보고됨에 따라, 신체의 노화를 지연시킬 뿐만 아니라 성 인병의 발병률도 감소시켜 주는 항산화 물질에 대한 관심이 증 가하고 있으며 이에 따른 연구활동도 활발한 추세이다(sies ). 또한, 세기에는 두 가지 이상의 기능을 가지는 기능성 식품 및 화장품들이 출시되면서 고령화 시대에 알맞은, 보다 젊 고 건강한 삶을 위한 제품 개발 시장이 매년 증가하고 있다 (song과 kim a; b). 영신초는 현재까지 항우울(lee와 chung ), 항염증(kou 등, ) 효과 및 성분 분석(zhang 등, )에 관한 연구가 young-je cho (�) e-mail: yjcho@knu.ac.kr school of food science & biotechnology/food & bio-industry research institute, kyungpook national university, university street, bukgu, daegu , republic of korea this is an open access article distributed under the terms of the creative commons attribution non-commercial license (http://creativecommons. org/licenses/by-nc/ . /) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. http://crossmark.crossref.org/dialog/?doi= . /jabc. . &domain=pdf&date_stamp= - - http://orcid.org/ - - - j appl biol chem ( ) ( ), − 활발히 진행되고 있지만, 미용식품에 대한 활성은 밝혀진 바가 없다. 하지만 영신초에는 항산화, 항염증, 심혈관 보호기능 등 의 다양한 생리활성을 가지는 astragalin, kaempferol (kim 등, ), β-sitosterol (li 등, ), isorhamnetin (kim 등, b), polygalatol (zhang과 shan ), coumaric acid (fu 등 ) 등의 성분들이 존재한다고 보고되어 미용식품 활용 가능성을 기 대해 볼 수 있다. 특히 야생화를 미용식품의 소재로 활용한 사 례는 드물고, 화장품 업계에서도 최근 야생화 등의 천연 식품 및 식물 자원을 활용 하는 것을 추진하고 있다(han 등, ). 따라서, 본 연구에서는 야생화의 일종인 영신초로부터 phenol성 물질을 분리하여 항산화 효과에 대한 기초자료를 얻고, 더 나 아가 주름 개선 활성을 보기 위한 elastase, collagenase 저해활 성 측정, 미백 효과를 위한 tyrosinase, 항염증 효과를 위한 hyaluronidase 저해 활성의 측정을 통하여 미용식품 활용 가능 성을 알아보고자 하였다. 재료 및 방법 실험 재료 본 실험에서 사용한 영신초(polygala japonica houtt.)는 약재형 태로 시중 한약재상에서 판매되는 것을 구입하여 oc dry oven (fo- m, jeiotech, daejeon, korea)에서 건조한 후 mesh로 분쇄해서 분말화 하여 사용하였으며, oc 냉장보관 하 면서 실험에 시료로 사용하였다. 영신초 추출물의 제조 영신초 열수 추출물은 건조 영신초 분말 g에 증류수 ml 를 가한 다음 용액이 ml가 될 때까지 가열, 증발시킨 후 냉각하여 시간 동안 상온에서 교반 추출하였으며, ethanol 추 출물은 영신초 분말 g에 % ethanol ml를 추출용매로 가하여 시간 동안 상온에서 교반 추출하였다. 각 추출물은 whatman no. filter paper (whatman inc., piscataway, nj, usa)로 여과한 후 rotary vacuum evaporator (eyela ne, tokyo, japan)에서 농축하여 추출물의 phenolic compounds를 - μg/ml 농도로 맞추어 사용하였다. total phenolic compounds의 함량 측정 total phenolic compounds의 함량 측정은 folin과 denis의 방 법(folin과 denis ) 에 준하여 측정하였으며, 시료액 ml 에 % ethanol ml와 증류수 ml를 첨가하고 n folin- ciocalteu reagent (junsei, tokyo, japan) . ml를 넣어 잘 섞어주고 분간 방치한 후, % na co ml를 가하였다. 이 혼합액을 시간 동안 암실에서 방치한 후 분광 광도계(uv/vis spectrophotometer, jasco, tokyo, japan)를 사용하여 nm에 서 흡광도를 측정하였다. total phenolic compounds는 gallic acid (sigma-aldrich co. st. louis, mo, usa)를 이용한 표준 곡선을 통해 양을 환산하였다. 항산화능 측정 항산화능은 , -diphenyl- -picrylhydrazyl (dpph), . -azinobis ( -ethylbenzothiazoline- -sulfonic acid) (abts), antioxidant protection factor (pf), thiobarbituric acid reactive substances (tbars) 실험을 통하여 측정하였다. dpph radical에 대한 소 거활성은 blios( )의 방법에 준하여 측정하였으며, 각 시료 ml에 μm dpph ml를 넣고 vortex한 후 분간 방치 한 다음 nm에서 흡광도를 측정하였다. 저해율(%)은 ( −시 료의 흡광도/대조구의 흡광도)× 으로 계산하였다. abts radical cation decolorization의 측정은 fellegrin 등( )의 방 법에 준하여 측정하였고, mm abts ml와 mm k s o ml를 혼합하여 만든 abts stock ml와 % ethanol ml를 섞어 만든 abts solution에 시료액을 넣어 vortex한 후 . 분간 incubation하고 nm에서 흡광도를 측정 하였다. 저해율(%)은 ( −시료의 흡광도/대조구의 흡광도)× 으 로 계산하였다. pf는 andarwulan과 shetty( )의 방법에 준 하여 측정하였으며, β-carotene mg과 chloroform ml의 혼합액 ml를 evaporator용 수기에 분주하여 oc의 rotary vacuum evaporator (eyela ne, tokyo, japan)에서 chloroform 을 증류시킨 후 linoleic acid μl, tween μl, h o ml를 가하여 만든 emulsion에 시료를 혼합하여 암실상태인 oc water bath에서 분간 반응시켜 nm에서 흡광도를 측정하였다. pf는 시료의 흡광도/대조구의 흡광도 비로 계산하 였다. tbars 측정은 buege와 aust( )의 방법에 준하여 측 정하였으며, % linoleic acid와 % tween 으로 만든 emulsion을 시료와 혼합하여 oc water bath에서 시간 이상 반응시킨 후, 반응액 ml에 tba/tca 시약 ml를 가하고 분간 , rpm으로 원심분리한 상징액의 흡광도를 nm에 서 측정하였다. 저해율(%)은 ( −시료의 tbars μm/대조구의 tbars μm)× 으로 계산하였다. 시료의 항산화능은 합성 항 산화제로 널리 알려진 butylated hydroxy toulene (bht)를 positive control로 사용하여 비교하였다. tyrosinase 저해활성 측정 tyrosinase 저해활성 측정은 hearing vj( )의 방법에 준하여 측정하였다. 반응구에는 . m sodium phosphate buffer (ph . ) . ml와 기질액 . mm l-tyrosine 용액 . ml의 혼합 액에 u/ml mushroom tyrosinase (sigma-aldrich co., st.) . ml와 시료를, 대조구에는 시료 대신 증류수를 . ml씩 첨 가하여 oc에서 분간 반응시킨 후 흡광도 nm에서 측 정하였다. 저해율(%)은 ( −반응구의 흡광도/대조구의 흡광도)× 으로 계산하였다. elastase 및 collagenase 저해활성 측정 elastase 저해활성 측정은 james 등( )의 방법에 준하여 측 정하였다. 반응구는 . m tris-hcl buffer (ph . ) ml와 기질액 . mm n-succinyl-(ala) -ρ-nitroanilide 용액 . ml의 혼합액에 . u/ml porcine pancreatic elastase (ppe) (sigma- aldrich co.) 효소용액 . ml와 시료를, 대조구에는 시료 대 신 증류수를 . ml씩 첨가하여 oc에서 분간 반응시킨 후, ρ-nitroaniline 생성량을 흡광도 nm에서 측정하였다. 저해율 (%)은 ( −반응구의 흡광도/대조구의 흡광도)× 으로 계산하였 다. collagenase 저해활성 측정은 wunsch와 heidrich( )의 방법에 준하여 측정하였다. 반응구는 . m tris-hcl buffer (ph . )에 mm cacl 를 첨가하여 -phenylazobenzyl oxycarbonyl- j appl biol chem ( ) ( ), − pro-leu-gly-pro-d-arg ( . mg/ml)를 녹인 기질액 . ml와 시료 . ml의 혼합용액에 . mg/ml collagenase (sigma- aldrich co.) . ml를 첨가하고, 대조구에는 시료 대신 증류 수 . ml를 첨가하여 실온에서 분간 방치한 후 % citric acid . ml를 넣어 반응을 정지시키고, ethyl acetate ml를 첨가하고 nm에서 흡광도를 측정하였다. 저해율(%)은 ( −반 응구의 흡광도/대조구의 흡광도)× 으로 계산하였다. hyaluronidase 저해활성 측정 hyaluronidase 저해활성 측정은 dorfman과 ott( )의 방법에 준하여 측정하였다. 반응구는 mm sodium phosphate buffer (ph . )에 녹인 hyaluronidase ( , u/ml) . ml와 . m phosphate buffer (ph . )에 녹인 substrate ( mg/ml) . ml를 시료 . ml에 넣어 oc에서 분간 반응시킨 후 . m acetate buffer (ph . )에 녹인 알부민 용액 ml를 첨가 한 다음 분간 방치하고 nm에서 투과율을 측정하였다. 대 조구는 시료 대신 증류수 . ml를 넣어 반응시켰다. 저해율(%) 은 ( −반응구의 투과율/대조구의 투과율)× 으로 계산하였다. hplc를 이용한 phenolic profile 분석 본 실험에 사용된 영신초 열수 추출물과 % 에탄올 추출물을 hplc용 메탄올로 : 으로 희석하여 syringe filter ( mm gd/x disposable filter device, . μm pore size, whatman)로 여과한 후 hplc (hp series , hewlett packard, walbronn, germany)로 분석하였으며, hplc 분석조건은 table 과 같다. 통계처리 본 실험은 회 반복하여 측정하였고, 자료의 통계처리는 spss for windows (statistical package for social science, chicago, il, usa) 프로그램을 이용하여 평균 ± 표준편차(mean ± standard deviation)로 표시하였다. 시료 간의 유의차는 분산분 석(anova)과 duncan의 다중범위검정(duncan’s multiple range test)을 실시하여 % 신뢰구간에서 검증하였다. 결과 및 고찰 total phenolic compounds의 함량 측정 phenolic compounds는 하나 또는 둘 이상의 수산기로 치환된 방향족환을 가지고 있는 식물성분을 말하는 것으로, 식물체에 특수한 색깔을 부여하고 산화-환원 반응 시 기질로 작용하며 미 생물의 공격을 막아 식물 자체를 보호하고 식품 고유의 맛과 향기에도 관여한다(alsalvar 등, ). 영신초의 total phenolic compounds를 추출하기 위해서 열수, 에탄올, 메탄올, 아세톤, 부 탄올을 이용하여 용매별 phenolic compound의 용출율을 확인하 였다(fig. a). 그 결과, 용매별로 추출하였을 때 열수, 에탄올 메탄올, 아세톤, 부탄올 등의 순으로 각각 . , . , . , . , . mg/g을 나타냈으며, 메탄올에서 가장 높은 용출량을 보였다. 하지만 미용식품의 소재로 이용하기에는 상대적으로 안 전한 용매인 열수와 에탄올을 사용하는 것이 바람직하다고 판 단되어, - %의 에탄올 농도구간에서 추출을 위한 최적 농 도를 결정하였다(fig. b). 그 결과, % 에탄올 추출물에서 phenolic compounds가 가장 높게 나타나, % 에탄올 추출물 과 열수 추출물을 사용하는 것이 가장 효과적이라고 판단되었다. 항산화능 활성 영신초 추출물의 항산화능은 dpph, abts, pf, tbars 활성 을 근거로 평가하였다. dpph법은 sulfur-containing amino acid 와 bha 등의 항산화제에 의해 환원 및 탈색되는 원리를 이용 한 실험으로, 천연물로부터 추출된 수용성 항산화 물질을 탐색 하는데 많이 사용되고 있다. - μg/ml의 농도구간으로 맞 춘 영신초 추출물의 항산화능을 dpph법으로 측정한 결과, fig. a와 같이 나타났다. μg/ml 농도에서 열수 추출물과 % table condition for operating hplc in the analysis of polygala japonica houtt. instrument hp hplc series . hewlett packard, waldbronn, germany column nova-pak c ( . × mm) column column temp oc injection volume l mobile phase a: h o, b: % methanol (a:b = : ) flow rate . ml/min retention time min detection nm fig. the content of phenolic compounds in the effect of various solvents (a) and ethanol concentration (b) on extraction of phenolic from polygala japonica houtt.. means with different superscript letters are significantly different at p < . by a ducan’s multiple range tests (n = ) j appl biol chem ( ) ( ), − 에탄올 추출물 모두 %가 넘는 저해율을 보였고, 동일한 농 도의 bht는 . %의 저해율을 나타낸 것을 미루어 보았을 때, 영신초의 항산화능이 합성 항산화제인 bht 보다 우수한 것 을 알 수 있었다. abts법은 abts와 potassium persulfate에 의해 생성된 abts + radical을 분해한 후 측정하여 항산화능을 알아보는 실험으로 친유성, 친수성 항산화제에 모두 사용 가능 하다고 알려져 있다(so ). - μg/ml의 농도구간으로 맞춘 영신초 추출물의 항산화능을 abts법으로 측정한 결과, fig. b에서와 같이 나타났다. μg/ml 농도에서 열수와 % 에탄올 추출물 모두 % 이상의 높은 항산화능을 보이며, 동일한 농도의 bht는 . %의 저해율을 나타낸 것을 미루어 보았을 때, 영신초의 항산화능이 합성 항산화제보다 우수하다는 것을 알 수 있었다. pf법은 β-carotene과 지질 산화 과정의 부 산물인 peroxy radical이 반응하여 생성된 inactive products가 free radical에 의한 연쇄반응을 중단시키는 원리를 이용하여 시 료에 대한 지용성 항산화 물질을 탐색하는 실험이다. - μg/ ml의 농도구간으로 맞춘 영신초 추출물의 항산화능을 pf법으 로 측정한 결과, fig. c에서와 같이 μg/ml의 농도구간에 서 열수와 % 에탄올 추출물 모두 . pf 이상의 높은 항 산화능을 보였으며, 영신초에 지용성 항산화 물질이 풍부하다는 것을 알 수 있었다. tbars법은 -thiobarbituric acid (tba) 시약이 불포화 지방산 자동산화의 부산물인 malondialdehyde와 반응하여 생성된 적색 복합체의 함량을 측정하여 항산화능을 확 인하는 실험이다(cojocaru 등, ; cheon 등, ). - μg/ml의 농도구간으로 맞춘 영신초 추출물의 항산화능을 tbars법으로 측정한 결과, fig. d에서와 같이 열수와 % 에탄올 추출물 모두 μg/ml의 농도에서 각각 . , . %로 높은 항산화능을 보였다. 항산화능을 알아 보기 위해 실시한 위의 가지 실험 결과들을 통하여 영신초 열수 및 % 에탄올 추출물에 존재하는 phenol성 물질들의 항산화 작용으로 인해 인체내의 free radical을 소거함으로써 천연 항산화제로서 의 기능이 우수함이 증명되었으며, 미용식품 소재로서의 활용 가능성을 확인할 수 있었다. tyrosinase 저해활성 자외선으로부터 피부를 보호해주기 위해 생성되는 eumelanin, phenomelanin 등의 melanin은 피부 색에 영향을 미친다 (kazumasa와 shosuke ). 피부 색의 변화는 melanin 세포 수의 변화, melanosome의 생산이나 구조의 이상, melanosome 의 melanism 등 여러가지 요인에 의하여 결정된다(kim과 lee ). 이러한 melanin은 l-tyrosine을 기질로 하는 효소, tyrosinase의 산화과정을 통해 최종적으로 생성되는 물질로 피부 를 검게 만든다(pak 등, ). 따라서, tyrosinase 저해활성을 측정하여 영신초가 가지는 미백효과를 알아볼 수 있다. 본 실 험에서 영신초 추출물의 tyrosinase 저해활성을 측정한 결과, fig. 에서와 같이 열수 추출물은 μg/ml의 농도구간에서 저 해율이 . %, % 에탄올 추출물은 동일한 농도구간에서 저 해율이 . %로 영신초 % 에탄올 추출물의 미백효과가 열 fig. antioxidant activity of water and ethanol extracts from polygala japonica houtt. (a): dpph, (b): abts, (c): pf, (d): tbars, w: water extracts, e : % ethanol extracts. means with different superscript letters are significantly different at p < . by a ducan’s multiple range tests (n = ) j appl biol chem ( ) ( ), − 수에 비해 다소 높은 것으로 나타났다. 하지만 μg/ml의 농 도구간에서 positive control로 사용한 kojic acid의 저해율이 . %를 나타낸 것으로 보아 영신초의 열수 및 % 에탄올 추출물은 미백효과를 나타내는 tyrosinase 저해활성이 다소 낮 은 것으로 판단되었다. elastase 및 collagenase 저해활성 collagen과 결합된 상태로 존재하는 elastin은 진피의 피부 탄력 을 유지하는데 중요한 기질 단백질이다. elastase 효소는 이러 한 elastin을 분해하여 주름을 생성시키는 주요 원인으로 알려 져 있으므로, elastase 저해활성을 측정하여 피부의 주름개선 효 과를 알아볼 수 있다(lee 등, ). 영신초 추출물의 elastase 저해활성을 측정한 결과, fig. a에서와 같이 - μg/ml의 농도구간에서 열수 추출물은 . - . %, % 에탄올 추출물 은 그 보다 더 높은 . - . %를 나타내어 농도의존적으로 elastase 저해활성이 증가하는 양상을 보였다. 따라서 % 에탄 올 추출물이 열수 추출물보다 주름개선 효과가 더 뛰어난 것을 알 수 있었다. 세포 외 기질의 주요 구성성분인 collagen은 피부의 탄력과 보습을 높여주는 기질 단백질로(perlish 등, ; kim 등, a), 단백질 분해효소인 collagenase에 의해서만 파괴되며 (demina와 lysenko ), 이에 의해 collagen이 파괴되거나 결핍이 되면 주름을 생성시킨다(kim 등, ). 따라서, collagenase의 저해활성을 측정하여 피부의 주름개선 효과를 알 아볼 수 있다. 영신초 추출물의 collagenase 저해활성을 측정한 결과, fig. b에서와 같이 열수 추출물은 - μg/ml의 농도 구간에서 저해율은 . - . %로 증가하였고, % 에탄올 추 출물의 경우 동일한 농도구간에서 저해율이 . - . %로 통 계적으로 유의적인 차이를 보이며, 농도 의존적으로 증가하는 것을 볼 수 있었다. 특히, positive control로 사용된 epigallo- catechin gallate는 강력한 항산화 작용과 다양한 피부개선 효능 을 가지는 것으로 알려져 있으며, 이와 % 에탄올 추출물을 비교하였을 때 μg/ml의 농도에서 각각 . , . %의 저해율을 보이며 유사하게 나타났다(hu 등, ). 따라서, % 에탄올 추출물은 피부 주름개선에 우수한 효과를 가지며 미용 식품 소재로서 이용 가능성을 제시할 수 있다. hyaluronidase 저해활성 hyaluronic acid는 glucuronic acid와 glucosamine이 연속적으로 결합된 고분자 다당류이다(meyer ). 고분자 형태의 hyaluronic acid는 macrophage의 phagocytic activity를 저해하여 염증을 억 제하지만, hyaluronic acid의 분해효소인 hyaluronidase에 의해 저분자 형태가 되면 상처를 회복하는 과정에서 염증을 일으키 게 된다(girish와 kemparaju ). 따라서, hyaluronidase 저 해활성을 측정하여 영신초 추출물이 가지는 항염증 효과를 알 아보고자 하였다. 영신초 추출물의 hyaluronidase 저해활성을 측 정한 결과, fig. 에서와 같이 - μg/ml의 농도구간에서 열 수 추출물과 % 에탄올 추출물은 각각 . - . , . - . %의 저해율을 나타내었고, 모두 통계적으로 유의적인 차 이를 보이며 농도 의존적으로 증가하는 것을 볼 수 있었다. 영 fig. inhibitory effect of water and ethanol extracts from polygala japonica houtt. on elastase (a) and collagenase (b). ethanol extract showed higher elastase and collagenase inhibitory effect than water extract. means with different superscript letters are significantly different at p < . by a duncan’s multiple range tests (n = ) fig. inhibitory effect of water and ethanol extracts from polygala japonica houtt. on tyrosinase. ethanol extract showed higher tyrosinase inhibitory effect than water extract. means with different superscript letters are significantly different at p < . by a duncan’s multiple range tests (n = ) j appl biol chem ( ) ( ), − 신초는 구내염, 골수염, 간염 등의 염증반응에 민간요법으로 널 리 이용되어 온 만큼(kou 등, ), 위의 실험으로 % 에탄 올 추출물의 항염증 효과가 매우 우수하다는 것을 확인할 수 있었다. 또한 고분자의 hyaluronic acid는 피부 내 수분함량을 유지해주는 보습효과를 가진다고 알려져 있다(seo ). 따라 서, 위의 실험 결과를 통해 영신초 추출물이 hyaluronidase의 저 해 활성을 가지고, 그에 따라 항염증 및 보습효과를 가지는 미 용식품의 소재로서의 활용 가능성을 제시할 수 있었다. hplc를 이용한 phenolic profile 분석 hplc를 이용한 영신초 열수 추출물의 chromatogram에서 retention time . , . 분에 peak가 두드러지게 나타났고, retention time . 분에서 peak가 얕게 나타났다(fig. a). 반면 영신초 % 에탄올 추출물의 chromatogram에서는 retention time . , . 분의 peak가 열수 추출물의 peak보다 배 이상 높 게 나타났으며 retention time . 분의 peak는 열수 추출물의 peak보다 배 이상 높게 나타났다(fig. b). 결국 영신초 열수 및 % 에탄올 추출물 간에는 추출 수율의 차이가 존재하며, 유용물질의 profile 차이도 존재하는 것으로 확인되었다. 따라서 열수와 % 에탄올 추출물 간의 미용 식품 활성에도 차이를 나타내는 것으로 사료되었다. 초 록 영신초의 용매별 phenolic compounds는 열수 추출물과 추출 최 적 농도인 % 에탄올 추출물을 이용하여 실험을 진행하였다. 영신초 열수 추출물에 대한 항산화능을 dpph, abts, pf, tbars 실험으로 측정한 결과, - μg/ml의 농도 구간에서 각각 . - . %, . - . %, . - . pf, . - . %의 저해율을 나타냈고, % 에탄올 추출물에서는 각각 . - . %, . - . %, . - . pf, . - . %의 저해율 을 나타냈다. 따라서, 영신초 % 에탄올 추출물이 열수 추출 fig. hplc chromatogram of polygala japonica houtt. (a; water extract, b; % ethanol extract) fig. inhibitory effect of water and ethanol extracts from polygala japonica houtt. on hyaluronidase. ethanol extract showed higher hyaluronidase inhibitory effect than water extract. means with different superscript letters are significantly different at p < . by a duncan’s multiple range tests (n = ) j appl biol chem ( ) ( ), − 물보다 항산화능이 더 우수한 것을 알 수 있었다. 영신초 열수 및 % 에탄올 추출물의 미용식품 활성을 알아보기 위하여 tyrosinase 저해활성, elastase 및 collagenase 저해활성, hyaluronidase 저해활성을 측정하였다. tyrosinase 저해활성은 μg/ml의 농 도에서 열수와 % 에탄올 추출물은 각각 . , . %를 나 타냈다. elastase 저해활성은 동일한 농도에서 각각 . , . %, collagenase 저해활성은 각각 . , . %를 나타냈 으며, hyaluronidase 저해활성은 각각 . , . %를 나타냈 다. 또한 열수 추출물과 % 에탄올 추출물 간의 생리활성의 차이는 phenolic profile의 차이에 의한 것이라 판단되었다. 이 러한 결과에 따라, 영신초 열수 및 % 에탄올 추출물은 항산 화능이 높아 천연 항산화제로의 이용이 가능할 것으로 보이며, 특히 주름 개선 및 염증억제 효과가 뛰어난 것으로 나타나 기 능성 식품 및 화장품 제조에 이용 가능한 천연 미용식품 소재 로의 활용이 기대된다. keywords 미백 · 영신초 · 주름 개선 · 항산화 활성 · 항염증 references alsalvar c, grigor jm, quantick d, 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( ) – © wit press, www.witpress.com issn: - (paper format), issn: - (online), http://www.witpress.com/journals doi: . /dne-v -n - - the beauty of architectural complexity robert barelkowski west-pomeranian university of technology, szczecin. abstract the paper is an attempt to revisit the concept of beauty which is analyzed in reference to vitruvian principles of architecture supplemented with idea, the fourth principle. the holistic approach to archi- tecture may be the vehicle to explain universal patterns of beauty, possible to be understood as complex system – both the discipline and constructs created as a result of architectural ideas. one can argue that architectural entities start their existence with initial idea, then its purpose is defined, to be encased in structure and form. all these principal bricks architecture is built with exist on multiple layers, as abstracts or as physical manifestations. the beauty is therefore the perceptive phenomenon, in which man is able to decipher and comprehend expressed or tacit properties of the universe and convert them into his own interpretation of the environment and man-made culture or social patterns. this paper is a tribute and humble contribution to pay respect to professor carlos brebbia ( – ), whose grasp of complex reality opened many inspiring paths within science and animated multiple connections within scientific community for the benefit of knowledge and understanding of the nature. keywords: architectural idea (concept), architecture, beauty, complexity, introduction the idea of beauty has always been at the center of theoretical considerations of what archi- tecture constitutes. it contributes significantly to our understanding of the role of architecture, its impact or mutual connection between people and their creations, in this particular instance creations of a scale enabling them to alter the environment. architecture appears to be a dis- cipline of science and art at the same time, it provides common ground for antinomies – the domain of the objective, and the domain of the subjective. it blurs the boundaries and becomes an example of applied science which defies some of scientific principles, e.g. usual rejection of single-case-based theories or case studies which is hardly applicable in architecture – in case of this particular discipline most cases are unique and the process of extracting general principles, theorems or rules becomes vulnerable to approximations, analogies, uncertainties in causal connections. when gordon graham ponders architecture as art, he rightfully sees architectural charac- ter as distinctive in comparison with other arts. architecture raises several doubts about the applicability of aesthetical values as primary ones, because it is useful, purposeful, relevant, and it is both designed and built with the extensive use of ready-made objects [ ]. its useful- ness is generally coerced, an inherent trait without which architecture loses its special status and may become something else, a sculpture, an object in space devoid of common mean- ings. this difference is at the same time significant yet intangible, without clear edges to what extent functionality defines perception of order and beauty. functionality, being on the one hand related to intended purpose, and on the other hand attributed as a result of multiple unpredictable occurrences, exposes the inherent evolutionary process of how architecture matures, achieves its independence from creator, designer, in fact anyone involved in its inception into built environment. i would argue that what nicolaus pevsner defined as archi- tectural “honesty”, architectural truth, reflection of zeitgeist [ ] is in fact the projection of r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) this particular feature the architecture has – the beauty within the innate order. it goes far beyond aesthetic properties, attempts to attach additional value to ordinary objects, enriches their values. in this work the concept of architecture is investigated in context of its main components, which architectural theory in the past formulated as usefulness, durability, and beauty, sup- plemented with abstract notion of idea responsible for initiating and manifesting architecture in multiple aspects. it departs from tri-fold utilitas, firmitas and venustas and revisits mod- ernist transformation of the three concepts. i argue that the notion of beauty implemented in architecture is different from the notion of form and aesthetics of architecture, and that even vitruvian venustas was seen by the ancient author as indivisible from other values and in fact all them constitute the beauty and its definition as proposed herein. therefore the paper starts with the introductory thoughts and perspective on this issue and provides considera- tions related to four architectural principles. there is superficiality and hidden qualities of architecture acting in unity, and their atomization, separation leads astray. the paper reviews four principles, discusses their interpretation, attempts to integrate these four elements, and proposes the insight into architecture relying on holistic view and exploits the perspective of complexity. architecture in its subtlety exposes human interpretation of holistic view of reality, includ- ing its holistic interpretation. this so-called truth, which roger scruton calls objectivity of architectural aesthetics [ ], unveils the most fundamental significance of architecture, a dis- cipline seemingly devoid of its own original, exclusive disciplinary field, one that is a combination of engineering, crafts, arts, rather than something autonomous. it is only an apparent lack of autonomy – its specificity lies in all-encompassing nature, in pursuit of syn- ergy in preparation and performance of architecture. thus the assertion that the beauty of architecture is in fact the reflection of its inherent complexity reveals the source of theoretical dilemmas in which beauty was mistakenly seen more as aesthetic attribute than multi-layered unity of various properties. this phenomenon, although diagnosed in different manner and described in different words, is a prevalent observation of many researchers of the theory of architecture, seen in the past as well as in the present [ ]. one may argue that the concept of architectural beauty is more similar to ideas found in science, to the concept of the same beauty that is found in nature – hidden rules allowing for simultaneous existence of order and chaos supplementing each other and making nothing but superficial dichotomy discovered in the environment, regardless of whether natural or artifi- cial (even virtual). the beauty found in scientific considerations, in mathematics or physics, as found in heisenberg’s memories [ ], or the beauty discovered in sophisticated geometries of parthenon in athens which import distortions and deformations (related to human percep- tion) necessary to transform perfect geometry into perfect beauty [ ]. the beauty of complexity of architectural idea the famous vitruvian triad determines the most significant values of architecture consid- ered throughout history of civilization. utilitas, firmitas et venustas – the three principles that stem from human understanding of the environment, both natural and one being the result of man-made artifacts and entities. these principles offered short but accurate descrip- tion of the nature of architecture – connection between inanimate objects and space imbued with purposeful thoughts and actions of people. it is important to see the intellectual domain as an integral part of the environment, despite the fact that it was obscured by modern rev- r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) olution in the th century. this transformative perspective is necessary to explain the erosion of holistic interpretation of architecture so prevalent in classic, ancient times, and hence the absence of complexity issues until they modestly reappear at the turn of the st century with works by christopher alexander [ ] and those by michael mehaffy with nikos salingaros [ ]. it is significant because architecture is, obviously, connected to architectural theory and its philosophical background, it is immersed in multi-science domain, making the meeting point for sometimes seemingly contradictory aspects of real life as well as scientific viewpoints. therefore, the deformation of architectural principles affects the interpretation of the theory and is reflected in simplification of perception of architecture, in the end leading to misunder- standing and misdirecting contemporary thinking. utilitas, firmitas, and venustas have been replaced with new ideas of function, structure, and form. while it may seem innocent, it replaces fundamental and abstract values with their restricted, fragmentary substitutes. func- tion is not an equivalent of usefulness – it is its contemporary, thus temporary, manifestation. structure doesn’t equal firmitas, because structure is only appearance, an effect of complex process of architectural embodiment. finally, the term “form” is not compatible with venus- tas, even apart from etymological roots of “beauty” reflecting the feature of an object being saturated with particular universal value. it is the understanding of unity of things exemplified in stuart burgess analysis of the beauty of peacock’s tail [ ]. the aesthetic complexity is the result of multiple coordinated phenomena: the shape, material, reactiveness to light, beholder’s eye structure, light trans- mission, bird’s movement and behavior. the perception is reduced to the admiration of shapes, variety of glittering colors, namely optical effects produced by thin-film interference, but comprehension of this phenomenon is impossible without seeing the emergence of the beauty from joint impact of multiple factors, some of them physical, others ideological, derivatives from human contemplative approach to reality. the conceptual pattern hidden in reality is exposed by murray gell-mann, who points out that the organization of the universe is recognized in the balance between regularities and irregularities in information chains coded in living species and inanimate things [ ]. gell-mann finds this self-regulating bal- ance in the organization of complex adaptive systems. while he points towards the ability to process regularities and produce (or re-produce) schemes prolonging either life itself, or its modes of organization, what is interesting is innate imperfection of the system, which is required to allow for change, for adaptation, for improvement and re-adjustment to changing conditions. architecture, being human creation, mirrors these schemes, and also mirrors the innate imperfections which at the same time bless architecture with ability to thrive, trans- form, adapt, as natural systems do. dealing with the idea, with the information, is what defines the start of emergence of archi- tecture – from the intent to the embodiment. necessity to organize patterns of social life is reflected in architecture in a selective way, however still conforming to the principles of complex adaptive systems. it requires, however, both regularities converted into schemes and imperfections retaining the system as an open one, indeterministic, self-organizing. while the former is often apparent and clearly recognized, e.g. patterns recognized by alexander’s team [ ], the latter is rarely seen as inherent or positive force of architecture. here it is important to make distinction between, what alexander describes as “dead” or “bad” patterns, and irregular patterns which are test platforms for change and in-programmed instability, because only these atypical schemes are responsible for vitality and validity of the system (of archi- tecture). r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) the beauty of the architectural idea lies in complexity of the concept mirroring what the idea attempts to define, solve, what it strives to anticipate – and its aesthetics is an integral component of thinking, also outside of aesthetic criteria of designed object. it is more the beauty of integrity, unity, than beauty of appearance. appearance is only a robe, a skin that tells us how profound this complexity is and how it affects external, formal aspect of architec- ture, how it build “architectural experience”. as we know, this experience is not constrained to superficial reception of building or space – its anchored in constant perceptive mechanisms, in continuous life experience. this is well explained by helmut leder et al. in their model of aesthetic appreciation and judgment, in which they emphasize context and input for experi- ence, perpetuality in performing analyses, implicit memory integration, explicit classification, evaluation, and affective / emotional processing [ ]. subsequent steps of this experiencing may be determined as, respectively, external, objective or semi-objective/independent factors corresponding to context and input, unceasing process (perpetuality), cumulative comprehen- sion of reality, resultant from integrating memories, and often comparative processes which can be linked to classification and evaluation. in other words, we simultaneously perceive and assess, and both integrated activities are producing our comprehension of the nature of things – the evaluation of their beauty. the creative process, e.g. architectural designing, is simply mirroring appreciation and judgment – it also uses spatial and temporal context and multiple sources of input, it requires constant re-evaluation due to wicked nature of architectural prob- lems [ ], it enacts inner memory, social memory, and semiologic code (which could be associated with sedimentation of social memories inscribed in abstracted signs) [ ]. this wickedness, these irregularities are generators of the random, nodes of emergence, loci of opportunities which sometimes lead to errors, but sometimes allow for creation of a master- piece. the imperfection assures this evolutionary bias, reflecting our evolutionary thinking also in perceptive and aesthetic spheres of our connection to reality. as paul hekkert writes, patterns generated by humans have this innate trait of adaptivity [ ], and hence any architec- tural idea also contains elements of unpredictability, random results, with perpetual adaptivity. the beauty in architectural function function is the aspect of architecture that is immediately associated with usefulness, with prac- tical performance of space. it is expected to provide the content, the result of transposition of an idea into something working, something practically responding to requirements. function represents the role of space of becoming socially driven vessel, containment for different pro- cesses and interactions for which function-related labels are merely signaling the purpose – to give an example of such performance one may still refer to what graham wrote on the purpose of architecture. he argues rightfully that while there is an initial purpose in the inception of piece of architecture, it is not permanent, it changes. at the same time he points out that future change of purpose or even seeming lack of thereof does not change this core value of architec- ture attributed to inherent potential of having a purpose [ ]. contrary to graham and other researchers like scruton, however, i would like to propose viewing particular sites as more than just arrangements in space conceived for admiration as they claim in case of those non-archi- tectural places. particularly i insist on rejection on karstin harries simplified interpretation of decorated shed, architecture reduced to the role of container [ ]. even if this is eligible from the perspective of designer allowing for specific approach to architecture as boundary, permis- sible for out- and inflows, restrained to determination of how transition between outside and inside grants the architect a comfort of dealing with limited number of problems, similarly to temporal aspect of architecture it doesn’t refute unity of shell and content. r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) function embodies specific architectural code inscribed in building to fulfill the tasks defined by the idea. it is not the set of volumes strung on some lines representing use-related patterns. these are more meaningful chambers conveying different messages, in good cases coherent with the entity, in bad ones dissonant. herein evaluation appears, our perception of “appropriateness” of the function, connected to the appreciation of beauty of functional structure. function is strong reference to beauty of the object, it initiates assessment and is inseparable from aesthetic principles, although not necessarily must play primary role [ ]. function brings understanding of internal structure, it brings comprehension of unifying qualities which make purposeful chains valid and beautiful. there are simple questions illus- trating this unity – can we ignore aesthetic component in how function is distributed within architecture? can we avoid calculating the importance of aesthetics of linking volumes in particular sets or chains to facilitate specific uses? aren’t these chains manifestations of inner order, profoundly connected to the beauty of spatial arrangements? if we are unable to find answers instantly, the unstable elements of functional program of architecture give us the clue about the relevance of beauty. while idea quickly becomes something blurred or even fades, function remains, but fluctuates or at least is prone to fluc- tuations. this openness of functional program is unable to include all implicit possibilities of use, yet designed space purposefully or intuitively provide these possibilities, makes archi- tectural object to deny any attempt to achieve equilibrium and promotes contained or forced self-organization. alterations in program explore ability of architecture to absorb and use specific connection between program and volumes. while idea is responsible for insertion of intended elements as well as, function exhibits human-related order of architecture, the order of human interactions and processes. the beauty in complex structure structure is different from function (and idea) significantly in that, apart from the processes of decay and decomposition, it is usually fixed and its potential capacity most often does not involve reconfiguration. the backbone for architectural form, structures do not divert from developing the aesthetically loaded constructs. if natural beauty is taken into account, it is next to impossible to point out any element which would be stripped from aesthetic content, although this content can be interpreted within the autonomy of any part, within the connec- tion between part and entity, as well as within entity perceived in its entire spectrum of existence. interestingly, structural thread of these considerations reveal relationship between physi- cal construction and (abstract) problem of truth. the architectural structure must follow rules of logic and support the performance – distribution of atoms support the rigidity of a crystal, leg bones assure dexterity and appropriate movement of a cat, structural veins of moth’s wing granting lightness, flexibility, and extremely good aerodynamics. the elements of construc- tion in architectural object play similar role and also express the purpose, the logic, the justification for existence. this kind of rapture becomes integrated on the field of bionics and bionic design, implying its latin meaning – the way of life. in this way truth of life is revealed, natural laws get exposed, and examination of natural world and purposeful design of sophisticated structure for architectural building have this urge to understand universal principles and the science of the world in common. while idea is inherently complicated and function has little possibility to avoid similar trait, while form may be independent, structure is a component prone to optimization [ ]. the nature, being the reference for humankind, shows how to compress, to use as little material as possible, how to innovate with materials [ ]. lan ma reviews different levels and layers of implementation of bionics, and r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) determines also its structural importance [ ], and what can be seen is intuitively appre- hended image of fascinating energy distribution of the system. guy battle and christopher mccarthy describe it as sculpting with energy [ ]. it may be easily observed in antonio gaudi’s work for la sagrada familia, the hanging chain model of gravity lines turned upside down to expose the optimal energy distribution of the system necessary to be converted into physical, loadbearing matter [ ]. so is there a beauty of structure? and if so is beauty an aesthetic concept or holistic con- cept in which one cannot separate the aesthetic component from the purpose and the performance of the object? architectural structure may not be seen, but regardless of its vis- ibility it is intuitively assessed, examined in terms of truth versus lie or disguise. contemporary architecture, using more organic, sculptural and also total forms in its appearance is, to some extent, a reflection of natural world, an imitation, sometimes a simulacrum, purposefully transformed and adjusted. and the language of new forms is in fact a closer approximation of the nature, the import of natural complexity integrated in shape – one which contains func- tion, provides shell for the content, supports itself. structure doesn’t change or change a little, but this doesn’t disprove its share in complexity – the compactness, thinning down structural volume only ever allows for acquiring sophisticated, yet purposeful architectural shells. this co-evolutionary trait and connectivity linking fixed or mobile but sustaining structure to other components probably was never sufficiently explored. structure adds logic of physical, mate- rial organization as reflection of human-related organization of spaces. function is rightfully seen as “negative” of structure – matter separating or joining contained processes. thus it becomes clear that instead of dichotomy these aspects explain the same idea, one following the other and vice versa – without any precedence. complexity of architectural form it seems that understanding of complexity of form is the most apparent, simple task in com- parison to other components of architecture. however, at the same time, the notion of form is burdened with aesthetic content apparently replacing and erasing any competition. form, if not restricted to shape resultant from construction, is seen as decorative, serving the purpose of admiration. this narrow view can be easily refuted by parallel to natural world, because after all social groups have some behavioral similarities to what can be observed in nature – the sense of place, urge to congregate and socialize. it’s attractive abilities can remind of tree perfect for providing observation point for birds who appear there in flock (let’s treat it as metaphor, not a literal association, with all provisions given by bruno latour while discuss- ing social interactions and distinctive nature of human experiential and cognitive abilities in such interactions [ ]). while many people interested in architecture may perceive that its output is brave and avant-garde, and that architectural trends are set by designers and their inventive, creative inner-selves, it is the opposite. the majority of architectural forms, even if produced by world renown brands, generate functional buildings, and just few are planned to be architectural icons – through careful process of economic planning, site selection, budget construction etc. special conditions must be met to allow for such a result, and then the role of an attractor, a gathering point, a place to be in, to engage socially, is the major factor justifying any fanciful attributes architecture can have formally. so this apparent fancifulness is a result of complex interconnected social, economic and spatial processes usually far from being whimsical, even if we acknowledge some failures or exaggerated spendings. processes are embodied in form which reflects all these phenomena in a sophisticated, complex manner, filtered through designer’s interpretative imagination/thinking, transposed into structure and shell intended to r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) express the meaning, the content, and the promise of undetermined occurrences. fortunately not all criteria must be reflected in equally masterful way and there is no need for any stand- ard or dogma, but still holistic approach to beauty, called by mike schlaich “elegance” [ ], is required. and architectural form triggers or responds to some social behaviors, accommo- dates them (by its attractiveness) or even creates. it is much more important for a form to have an implicit meaning, influence, and associative powers, than to express shape, color, and material, although the latter are necessary to convey the former. the architectural form is addressed to everyone ready to receive signal, message, and to process it, interpret, evaluate – it is not admiration per se, it is instant comprehension of inner complexity of form as a reflection of interwoven threads of reality, again. profound perception of complexity? we have reviewed different aspects of beauty of architecture and architectural entities. vitru- vian triad has been extended to initial component of architecture – the idea (ideological content). the inclusion of an idea is herein postulated as compulsory, because the immaterial is equally important in architecture and influential for its existence and performance as remaining, traditional virtues discussed in the ancient times by vitruvius. the code to deci- pher this beauty is complexity, or maybe it would be more precise to say that beauty is what emerges from perceiving the code of complexity. architecture doesn’t mimic socio-spatial reality, it interprets it and exposes coherent (or incoherent) vision of social organization and uses tools defined as principles of complexity [ ]. architecture emerges from idea through purpose (function), and then it is nested within structure and manifested by form – forming link between immaterial and material, psycho- logical and physical, mind and body, completed with subjective, personal experience acquired through reception of integrated entity. the user, the recipient, the observer receives instant, compacted information containing traits of all these four components. the perception of beauty becomes a discovery of truth hidden within social and cultural patterns, of how they work, how they interact and how they are composed into systems or sub-systems, analogous to complexity of universal, natural clusters or systems. this phenomenon touches human beings as well as constructs or other objects. emilio del giudice and alberto tedeschi notice that human beings, as other living organisms, are coherent systems open to the external world and consequently be able to tune their own oscillations with the fluctuations of some part of the universe [ ] – and the feeling of beauty may be therefore interpreted as the decoding of this connection. architecture becomes a vessel for anthropic perspective of understanding the sense of being, the sense of coherency present in all-encompassing, unified reality – all layers of this reality recognized with transdisciplinary approach required to understand holistic image: it builds the ontological axiom, the logical axiom, and the complexity axiom, as basarab nicolescu puts it [ ]. the beauty is the knowledge of interdependencies (having similar properties to scientific knowledge, inherently contaminated with subjective perspec- tive of a researcher – there is no objective science, only objectivized, although we strive to achieve this objectivity), simultaneously internal and external [ ]. we observe in architecture (and in architectural objects) what michael baranger writes about complexity: non-linear interaction of constituents (or components), their interdepend- ency, multi-scalar structure, generation of actions or behaviors, integrated connection or unity of chaos and order (which baranger calls non-chaos), coexistence of competition and cooperation – integrated reinforcing or weakening impact of architectural factors [ ]. and r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) when stanley stein and michael mcmordie critically assess the loss of central role of beauty, they imply not the superficial concept of beauty, rejecting the formalistic approach to this notion. they quote an important thought once put forth by ludwig wittgenstein referring to common attributes sought for in human rapture with reality that it is similarities and relation- ships [ ], not repetitive, common patterns that build multidimensional experience of beauty – people communicating their understanding of nature enriched by social and cultural pat- terns through architecture, to each other and with the purpose to mark their presence. the imprint of primal, natural imperative can overcome limitations of assessment and knowledge as phenomena attached to particular spatio-temporal reality, thus to particular moment and particular being – because they have universal framework. it is hard to believe that this approach to the notion of beauty can conclude or narrow down the discussion on how beauty should be interpreted. however, too many interpretations are fragmentary, focused on limited concept of what architecture is, particularly when it is per- ceived as formal expression of inanimate matter in which proportions or even mathematical relationships are treated instrumentally without looking for their hidden meaning. i would argue that architecture which is the unwanted muse among others, those who are representing seemingly more autonomous arts, requires more profound perception, and that this percep- tion can be achieved through complexity and its principles. it seems that this framework and multi-layered picture of complexity and its image – the experience of universal beauty – can, to some extent, help overcome multiple apparent contradictions within the theory of architecture. references [ ] graham, g., philosophy of the arts: an introduction to aesthetics, routledge, oxon and new york, . see pp. – . 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[ ] sauchelli, a., functional beauty, architecture, and morality: a beautiful konzentrazion- slager? the philosophical quarterly, ( ), pp. – , . https:// doi.org/ . /j. - . . .x [ ] sadri, m., kavandi, m., jozepiri, a., teimouri, s. & abbasi, f., bionic architecture, forms and constructions. research journal of recent sciences, ( ), pp. – , . [ ] battle, g. & mccarthy, c., sustainable ecosystems and the built environment, wiley- academy, chichester, . see pp. – . [ ] ma, l., from bionic design of the high-rise buildings, nd international confer- ence on civil, materials and environmental sciences (cmes ), london, the uk, pp. – , . [ ] op. cit., battle and mccarthy ( : – ). [ ] huerta, s., structural design in the work of gaudi. architectural science review, ( ), pp. – , . see pp. – . https://doi.org/ . /asre. . [ ] latour, b., on interobjectivity. mind, culture, and activity, ( ), pp. – , . see pp. – and – . https://doi.org/ . /s mca _ [ ] schlaich, m., elegant structures. the structural engineer, , pp. – . see p. . [ ] barelkowski, r., design process as complex system. international journal of design & nature and ecodynamics, ( ), pp. – , . see pp. – . https://doi.org/ . /dne-v -n - - [ ] del giudice, e. & tedeschi, a., science and aesthetics: how beauty can emerge from matter. international journal of design & nature and ecodynamics, ( ), pp. – , . see p. . https://doi.org/ . /dne-v -n - - [ ] nicolescu, b., methodology of transdisciplinarity – levels of reality, logic of the included middle and complexity. transdisciplinary journal of engineering & science, ( ), pp. – , . see p. . [ ] ibid. . r. barelkowski, int. j. of design & nature and ecodynamics. vol. , no. ( ) [ ] baranger, m., chaos, complexity, and entropy: a physics talk for non-physicists, , available at necsi.edu/projects/baranger/cce.pdf (accessed april , pp. – . see pp. – .) [ ] stein, s. & mcmordie, m., beauty and character: values beyond beauty in architecture. interchange, ( ), pp. – , . see pp. – . https://doi.org/ . /a: ~ * * $ o~ can indulge yourseif with the third category; by tiiat time it is probably too late to worry unduly about winning ot losing. it is the second strategy t am going to adopt, yet it is not in my self-interest to specify which of the problems i regard as "easy, tough or entertaining". may i add thnt i will not cover mixing. ct violation or traiy rare decays. there exists a triple motivation for dedicated work in this field. j. charm and beauty decays present us with a rather ui» learn important lessons about qcd on the interface between tin- pnttirbativr and non-perturbativir regimes. open flavor states q - • tvh} w if eq. ( ) were confirmed by inon- data, wo roiijil not claim to have- ncic-s- satily a theoretical disaster at band after all there is an old prediction consistent with it. yet it would constitute at least nn iieule emtarawiiiml in practice since all the detailed models of more n-reiil vintage point in in direction of eq. ( ). if eq. ( ) were to hold up in spite of the ratlier general the former is thus determined by the understanding of the latter. the outline of the talk will be as follows: in section ii, i will analyze charm decays, both the present understanding and its future refinements; in section iii, i discuss beauty decays with particular emphasis on |v(c )| and |v(u&)| before concluding with some remarks on the future in section iv. [n general, i will not present a comprehensive review with all numbers and experimental findings; those can be found in other talks at this conference.' instead i will focus on the most topical features and pans theoretical judgement on them. ii. the decays of charm a. lessons on strong interactions in d"/d* decays. . scmi-i^plonir d°/d* ducays. tlicsu decays tin: not expected to pomr as big a theoretical challenge as non- it'plonir tlrrays since* uiry involvooiity imr typtf «»f liailroiiii- inalrix clr-mrnl: <(.*>= , )\j,,\l) >. a host or models have been put forward to calculate those. a lypic-al tine was developed by daucr, stccli and wirbcl (=bsw);'" others will l>e mentioned later: 'hswi / ' - '('a*, a) ~ ( - ) • l o ' v c " ' ( ) wliich coinpiircs favorably with the data rttt>[d -» t»k*i k) ~ { . ± . ). l o ' v c * ' . ( ) * (om,-|»r+) * " ' i,j = , , ...ne- naively, just counting numbers, one might expect £ s something has t o be d e a r l y kept in mind here: it is {trivially) tine, t h a t chain ing the values of c& can offset almost any change in £ {apart from (tfi + ) i ( a ) - «j) ? ( — £*)(! +c))- y*** *'*' s observation amounts t o l t i l l c more than numerology, since the origins of these parameters are very different: c.± art? due to h a r d glucm effects, on t h e other hand t o soft ghmns. kq. ( ) shows there are three categories of decays; • class i transitions: d" — a/,' m^', only the* a% tens* contributes; • class !t transitions: ip -* */{\wf; o n ' v ^ k " i term contributes: - class iii transitions; d* -» htfaf?; both «i and ,« to be determined from the data plus a not insignificant amount of "poetic license" entering expectatipu y{b -* rva"*) — v(d -* tvli), one had t o view t h e success of these models in accounting for hie considerably more complex non-lcptonic decays as i% mere coincidence. furthermore one should then tru st them even less itt b decays despite some early evidence t o the contrary as i will discuss later on. considering these for a theorist - unpleasant consequences, i feel strongly inclined to belief t h a t lit). ( ) does not represent t h e last word - t h a t instead it will go u p uy a factor of two or so. . noh-leptonit- d"/d* decays. (a) t h e "art of theoretical engineering" in an effort to be practical and t o concentrate on the doable, stech and coworkers have developed a. phenomenological framework to deal with non-leplonic decay modes. all transition amplitudes t(d —» / ) are expressed as a linear combination of two more elementary amplitudes with fixed coch)tie»ts: t( d - / ) = «,t,{ d - f) + <*&{ d - / ) ( ) fli = ^ ( c + + c . ) + | ( c + ~ c „ ) ( ) « ^ - ( c + - c . ) + | ( c + + c . ) . ( ) t h e renomialization coefficients c± are produced by qcd radiative cor rections; c± = holds in t h e absence of qcd. the parameter ( denotes t h e relative size of matrix elements in color space; e.g. s - adding tip tth{d — pp,pv, vv) where the d -» pp,pv modes have been mote or (ess confirmed experimentally and comparing it with r „ p ( d ) one finds t<£> -» f p , pv, vv) ~ . x i w ^ a s ) c ) !"(£>+ - £ u k / k ; pp, pv, vv)~ k } the two-body modes thus dominate non-lcptonic f) decays and the global features of d decays arc wci) reproduced. and all of this is achieved without any contribution from weak annihilation! a more detailed took reveals some phenomenological drficiencius: • the predicted values for bli{d° -* k" >< a'*w, f<*t}} are all lowftim- pared to the data. i do not perceive this as a major problem. they ail represent class ii traasiliow*, i.e., are smallish — c)fj%); llras even relatively small rescanning from the large class i transitions will have a big impart on them white affecting the* overatt picture very little. r i d ^ a ^ f * - experim. h o " - » * + » - ) . iheoret. i will come back to this point later on. b via the formfactors adopted and final state interactions(»fsl) that are included. thift "poetic license" certainly introduce* some fuzziness into the theo retical description. yet even so it is highly non-trivial - and regard it as significant - that with « i = s . ± l , a j * - . ± . l ( ) a very decent fit is obtained to some twenty-odd epfd* decay chan nels! a priori then- is no mason to expect that one set of values for oi.d] should be adequate to describe so in any so diverse decays d -* /'p. pv where v\v] denotes pscudoscalar [vector] states; for the kinrmaticaland dynamic") environment*, i.e. phase shifts, vary very significantly. yet we learn from the success of i in- fit that llirw is a simple- pattern underlying charm dec-ays. the specialties or individual channels can be factored off into the rather simple rormfarlurs and fsi employed thus allowing a universal value for «i,«-j. even so soft gluon effects play an important role. for k.|. (ii) leads to when adopting the usual values for t t , i.e., c + «- . .c_ - ' . . further pleasant surprises emerge from this analysis: (c) the "high tt superconductor" approach. there is one approach that will (hopefully) scilve all our problems and settle all issues once and for all - the use of lattice monte carlo calcula tions. however, like with high , superconductors, its benefits will not be reaped in the very near future; quite a few yearn will pass before it will yield definitive results on charm decays. (d) "best availableti-chnrilogy": qcd sum rules. this approach involves three ingredients • one employs an operator product expansion - / , = , / * ( * , + £ + o ( i j ) ) - ( ) for actual calculations one retains only the leading term - bf - and drops all non-leading contributions bt/n, etc. this represents the basic assumption. from it follows: • £ = effectively since it is of higher order in ^ : £ = jj- - factorization holds; • w exchange and fsi have to be ignored. the description of the data obtained in this approach is not bad, though definitely poorer than in the stech et al. approach. this can be traced back largely to the fart that fsi effects are ignored, on the other hand this approach is certainly more compact and obviously self-consistent since it is based on just one basic assumption, namely ignoring terms that are non-leading in ^ . this one assumption however is purely ad- hoc. non-rftl&tivistic potential model they are related to the hftdronic wavefunction at the origin where m denotes the meson mass. on very general grounds, one expects fo < h • specific models yield'" (with the normalisation / , «* mw) ft, ~ - mv.v , if ~ i« - mc.v . ( ) mark iii has obtained"" fo < + —* ft+v. ofcour.sc, it. h highly desirable to improve the sensitivity on jo, hopefully reaching (in- level indii alrtl in k(|. ( ); of course, it is equally desirable to obtain a comparable miinbi'i' i>n //.-. yet even eq. ( ) represents a very intriguing bound, in particular if nu<> adopts the prescription iif non-relalivistic dynamics, [ty. ( ). i'«>r in llml ease fboi./^s.fli&n mr\' ( ) v m » a number of great relevance in dealing with b° - fi° mixing. http://ofcour.sc block and stucmttn * have developed and applied sneb an analysis to d -* pp, pv ( ) decays, where one has six (it parameters altogether, namely three for &*,d+,ds —• pp and three for ep,d*,ds -» pv, yet many more decay modes. since the theoretical analysis involves four-point functions rather than two- or three-point functions, it represents a very ambitious and chal lenging program. therefore one has to grant it rome time for maturing, liven m> t\ lir*l »>inly»is yields very prninining results by producing a rather decent (it to the "old" mark iii crunching ratios; in particular / /f(/>° -» a' *) - % ~ hrilp - . jt°ta) is obtained. since six pa- riunelers liave to lie filled otie has to redo the analysis with the "new" ma uk iii luhhflmig r.iliiis, j'ct i do not anticipate a major problem t«i emerge. therefore, i would like to smnniniiye why i ronirider this nppruacli mi) priunisiiig. a priori one doe* not make ajwumplionti like factorization or ignoring weak annihilation or noii'leading terms hi j$. nori-fatiorizable contribution* an' actually included and treated in an ;iv lejwl m'iiit-tpianlitalivi* fashion. tin- dominance of factorizable con- lril)iilitmi> i-iihtkcs i lien self-consistent ly from the duality match-up, yet other term* like w cxdi.iiipv are still present on the *» % level. i'un-iy l.rptoiuc decays. l-'roni the branching ratius o* ~* t*v,d+ —• t+v one determines very im portant lmdrpnic parameters, namely the decay constants fa and fp. in a mdi ,£+k l}mm') = o- * "-w ± . £ ( ) ^ ^ ^ ^ = ^ = . * . * . £ . ( , and an upper limit up to this conference no decay mode / had been found with bh{d+ -> <>*+) since one estimates theoretically br{dt - • ^ r + ) - % one is then lead to the question: "where and what are the non-leptonk df decay modes?" while it is true that theoretically one tends to expect two- body modes to be less dominant for d, than for d° decays this occurs only on the ~ % level, i.e., it is not highly significant. it was a very pleasing experience at this symposium to hear from both the mark ii and iii groups about preliminary findings that with a possibly even large signal for d* —» q's" d. cross checks in d, decays. a pleasantly simple dynamical pattern has emerged from da, d* decays: < two-body final states dominate non-lcptonic /j°, d* decays. • the large d* — d° lifetime ratio is dominantly though maybe not ex clusively produced by a destructive interference in d+ decays. accepting these findings is however tantamount to giving up much flexibility in treating dt decays - the model parameters have been basically fixed. d. decays thus offer us quite honest tests of the statement that -we have indeed developed a rather satisfactory understanding of d decays. quite a few very interesting experimental results have been obtained in the last year on d, decays. as far a* the overall rates arc concerned, the news have been mixed. the good news has been that t(d,) has been found to agree with t(£j°) within quite decent errors: ^ } - l * ± f l - » - ( ) the bad news are that still no absolute branching ratios are known. the importance of d, decay modes can then be expressed only relative to the "standard" mode d+ -* * t + . definite numbers have been given for three other modes: / . db . ± . e . ± . mark ii ( ) . ± . argus v . — . theoret. might hold. blok and shiftnan find large isospin cancellations in d, pie: br{d+ -* pv*") br(d+ -* wt+) £ . ( ) with d, —• w » + still being suppressed relative to d. -+ >ir. any data on d, -* wr are thii highly desirable, though hard to come by. h should be noted that the reaction of eq. ( ) could not contribute here. - quite a new element enters it indeed ur(d* -» n ' * + ) ~ br{d* -* i}**) ~ im(d+ -» fa*) ( ) were found since factorization yields typically ' br{d* — i?v + ) ~ stf(d+ - ?ff+) ~ £ « ( / ? + - * + ) . ( ) tin: presence of a nearby scalar resonance would offt*r it natural <"xi>l;i nation for aii enhancement in !), —» t}w,t)'tt n\nev + — t / j + / • / ' v . (.sh) also it should be noted that + / • :** ( ) such a scalar resonance would therefore not contribute to d, —> ir. while the spectre of "missing d* decays" is thus receding, many intriguing observations can be made: • the relative weight of the class ii tradition d, - * r*a'+ and the class i transition dt —* ^ t + is as predicted, eq. ( ), • the biie ti the non-resonant d, -* kkir mode is only about % of the tesonant modes, eq. ( ) - again as expected. • the d, does decay into final states without open or hidden strangeness, eq. ( ). annihilation processes thus do occur, though with a reduced rate, namely with only - % of the strength of spectator processes. • the light upper bound on d, ~» />°x+ provides some prima facie evi dence that d, —» itjtt is generated by weak annihilation and not just by fsi. tor in the latter case one would expect br{d+ -» p°ir+) £ bfi(p* —» r+jr" t+) unless some accidental cancellations take place. to look at it in ,i xlighliy different way, there could be a * like, i.e., pseutlascalar resonance t with m , — m{ot) that enhances apparent an mill million transitions dt^rt'~*nr ( ) whew f.' parity requires >i = odd. h would be only natural to expect + -t f(, ;jc+ uv wc\»f ihut way as well. • there is one loophole in this nrgumeiit that can be dosed by further observation: tin- beijing group has suggested that " ltlt[lx* -> <&*+) - dh[dt ~> w:r + ) > br{d+ - p°v+) ( ) su{$)fi breaking in eqs. ( , ) has been implemented basically via (//f//*)* > i, maybe one has overlooked another important source of su(z)fl breaking. this can be checked quite clearly in /> + decays: nz- >mi'**'"n m where ps denotes the relative pliasespace factors and f ^ i measures su{z)fl breaking. maybe fsi or weak annihilation has not been included properly. mea suring d° ~* k°k°, arv while not an easy task would help greatly in disentangling these effects. one warning is in order here: contrary to some claims, weak annihilation can — despite the gim mechanism — produce d° -+ /<°a'u due to su( )fl breaking! once the first two loopholes are closed one can turn one's attention to the most intriguing explanation for eqs. ( , ) - penguin operators! for they contribute to both zj° —» k*k~ and d° —» jt+jt- with a positive sign while the usual charged currents contribute v.-ith a positive [nega tive] sign to * - * k~k* [£p —» r+x~]. therefore even a suppressed (coherent) penguin amplitude can have a significant impact. is as a final remark or appeal for data, we would like to know the scmileptonic branching ratio. in particular, does br(d, - • ft/x) ~ br(d° -» (vx) hold or br{d° -*tvx)< br(d. - tvx) < br[d+ -* tux) . also the composition of the hadranic state x is of considerable interest: x = r\, t j ' , tj>, u>> it's . c. refinements . once cabibbo suppressed decays the oldest pu zle in charm is represented by the following two transition rates r { / > ^ k + ^ ) = | - i ± q - x i ° - c - z , < > r ^ ^ ^ o ^ l ' ^ ' ^ l o ' ^ e c " r**" ( theor. three mechanisms can be invoked to explain r(d° ~* k+k~) > r(d° -+ ff + t'). the beat numbers on these km parameters at present | v ( « ) | = . ± . \v(ei]\ = . ± . ( ) are obtained ftom the di-muon signal in deep inelastic neutrino scattering. i am optimistic that in the foreseeable future more precise values can be extracted from d -*• ivk, k*tr,p. h i . t h e decays of beauty dedicated studies of beauty decays promise an extremely rich harvest: the a priori unknown parameters v(c ). v(ub) can be extracted, ff - b° mixing can be studied, rate decays and finally cp violation can be searched for. this is all true in principle; in practice however a lot of very hard work of not necessarily the most lucid kind is required since it ia the hadrons that decay, not the quarks. this is the issue want to address. a. v(th) in semi-leptonic decays. already anticipating that |v(« )| » jv(m )j* we can write down the crucial question is what kiad of function is involved here. no jjencral answer to this question exists. therefore we take recourse to a time-honored stop-gap measure. we employ different models of reasonable, though not always overwhelming integrity and hope that their differences in the output represent a good measure of the inherent uncertainties. . doubly cabibbo suppressed decays. thews are (at least) two reasons why one wants to find and underataod as * —ac transitions like z>+ -» k+ff+jr~ . ( ). • the neutral counterparts o( eq, ( ) - jd° -» jfit+tr-, k*t~kv - form an important background to present searches for d° — £fi mixing!" • such transitions can exhibit a high sensitivity to new physics in the form of charged higgs fields, for old physic* transitions get suppressed by ty* c ~ . x ~ when going from as = ac to as = —ac processes; charged higgs contributions on the other hand can get enhanced hy ) a* \ ( ) . ± . bsw the exclusive modes can of course be calculated as well in such schemes: from the recent argus measurement' " br{b° — it-e+vt) = ( . ± - ± !.&)% ( ) one concludes f ' < ± o. \v(cb)l ~{ x ( ) . ± . in pleasantly good agreement with eq. ( ). by the way, this is one major reason why i fiod it hatd to believe that the same models could fail by a factor two to three in d —»tvk* vs. tvk. putting everything together one obtains ! . ± . giw - ± . quark level ( ) . ± . bsw the models thus exhibit a roughly % internal uncertainty by themselves. yet the real message of eq. ( ) is that the true overall uncertainty is much . quark level description. the spectator ansatx leads to r ( b - £vx) * t{ - iuc) = ^ ^ |k(d)|* /y ( ^ f ) ( ) k{x) = - x + x - xa - *a log x . ( ) from the data on tb one then deduces \v{cb)\spcz . ± . ( ) where the uncertainty reflects mainly our inability to make a unique choice for the quark masses m& and m e . it describes only the uncertainty reithin a. single simple model, but not the theoretical uncertainty in general. among other things one has assumed here implicitly t ( s * ) = t(b°) - an equality that has be>'n checked experimentally only withid a factor of two. . hadron level description. quite a. few different mode) descriptions have been suggested in the litera ture. i will concentrate here only on two of these since they seem rather complementary to me. these are the descriptions provided by grinatein, isgur and wise (=giw)"" and by bauer, stech and wirbel ( = b w s ) . w there one finds t{b -, tv dfd') ~ { j ; j j ] x |v(rf)|» » sec'* £ ™ . ( ) id these models one expects, cum grano satis, these two final states t o almost onb-* li/it. since r{b+-*?t*») . f . |v(iifc)l* giw one obtain') ' v ( h j < / . l giw | v ( o r l o.n bsw . ( ) quite consistent with eq. ( ). one important caveat ia in order here: at our present luvel of understanding (or limitation thereof) one has to exhibit "brand name loyalty," i.e., stay within o n e hadronization scheme (giw or bsw, etc.) when quoting num bers ou the km parameters. for nthrrwisc one can fall into ok: following trap: combining \v{cb)\ £ . as obtained from bsw with the (ilw boimrl |v(ub)[ £ . leads to \v{ub)\ :£ . . while this value: might happen to he- correct, its derivation was inconsistent as shown by eq. ( ). c, non-leptonic decays and the impact of strong interaction... as in d decays, it is useful to distinguish between dims , , ami tit transi tions. in the following tabic, i list bsw predictions for some- tyiw'ai modes together with present experimental numbers: larger, namely \v{cb)\ ~ . - . ( ) i . c , a factor of two - despite the more optimistic pdg claims! i sincerely hope that pdg will state a more realistic evaluation of the uncertainties in their next report. eq. ( ) also shows that the duality concept as implemented by eq. ( ) is not failing - after all \v{d>)\ = . ± . is consistent with both the giw and bsw value - yet it does not provide us with * surgical tool either. one should aim note that so far nobody has presented a proof why eq, ( ) should work better and better for increasing my. b. v(ufr) in scmi-lcptonic decays. two methods have been used to distinguish i - m from b —* c transitions. i. one tries lo exploit kiiicmalical differences as exemplified by m, > m b . no clear signal lias hec.u found by cleo or argus. a great deal of model uncertainty enters when one translates this into a limit on v(ub): \v{ub) i v(cfc) $ . - . . ( ) . one attempts to identify hie hadronic final state. cleo has searched for ti* —» t*i't(f* and round no signal. ilencconc concludes , , „ „ , „ fo. ' giw ^ "<")£< ( ) u. n s w , it i« tempting, though less than rigorous, to relate this to the argus findings since two-body modes do not dominate non-ieptonic b decays as they do with d decays, i estimate l s ^ s t . . ( ) extrapolating from t(d+)/t(d°), i expect weak annihilation to be fairly unimportant in t{b): t(b°) should not be shortened by more than ~ %. however not everybody agrees with this expectation and in any case it has to be checked experimentally. d. baryonic decays of b decays. beauty mesons are sufficiently heavy to a!jow decays into a baryon-anlibaryon pair possibly together with other mesons. furthermore the weak decay pro duces already two quarks and two antiquarks bq —+ cavq . thus only one more qq pair has to be created from the vacuum to form a baryon-antibaryon pair and such baryonic decays should not be particularly suppressed. the drawback is that it poses a non-trivial problem to make these statements more quantitative. two prescriptions have b«:en put forward to predict the inclusive baryonic branching ratio: both use di-quark production as a starting point although they treat it in a different manner. the results are " o „ , „ . f ± % ref. br{b — \ c + x)= i „ ( ) a mode br[%]bsw bh[%)exp. class j : oi # > - . £ > + * - . | ^ | , ± . b° -» d+'tf" . | bg*|* . s ± . ± . ba - • d***"* . |ejs£|" . ± . ± . if tc-lfl = p" £!<:« / / j a* < = s o - ^ t f * . , . ± . clats iii : ] , a j £ = b " - d ° t t - « |^f . ± . ± . considering the rather limited experimental information one cannot draw firm conclusions from this juxtaposition. yet the following tentative state ments are suggested: • we appear to be off to a good start in deacribing non-leptonic b decays consistently with \v{cb)\ ~ . . > { = is strongly favored — like in d decays, despite the vast differences in kinematics, prominence of fsi, etc. • relatively little negative interference occurs in the two-body modes of b" decays. specific statement. the arguments can typically w phrased as foilows r ( f c ^ a ) = ^ . b - c t t r ( f l - p p t v ) ( ) with r ( b ° — p p r * * - ) ' ~ r(b->.\n*v) ( ) t(b-nrtx)' just countingthe number uf available states one arrives at order of magnitude t'klitnatcs c ~ , „ ~ !i - . ((b) ft, is modelled aft^r baryonic dec ays of the /)] — ,:j. making "reasonable * variations in our assumptions one arrives at n rather wide range v/(ct) | this strongly siigrcsu though docs not prove rntirhisivrly thai |v(ti )/v{efc)j would be as large as it is still (barely) compatible with tin- as in fine agreement with the clgo findingn br{b - a, + x) = ( - ± . )% . ( ) that is nice, but so what - these prescriptions are still semi-quantitative at best. firstly, jf arguments can be invoked to improve the theoretical underpinning of the arguments sketched above. secondly, data on exclusive baryonic modes would help trenwitdotwly t*» refine these concepts- thirdly, the very urw arc!us data uit charmless b decays force t)iin issue upon un ijr(b+ ~> ppx*} = ( . ± . ± . ) x io"" ( ) bli(b" -* pjiir+ir-) = ( . ± . ± . ) x lo"" compared i.o tin upper liriiits i>l>lninc jva t /vaff'a ( ) the two-body modes b —* aa are - as usual - suppressed in amplitude by a form factor, f{q*\ f v ) « ( ] + ~ y . (-si applying the qcd counting rules of brodsky and lepage, one arrives actually at n ~ , i . e . a dipole (instead of monopole) form factor since the exchange of two hard momenta is required to produce —* baryon- antibaryon. such a highly effective- suppression can lie balanced only by maximizing the mass-tike parameter aj. thi# leads t o the very general analysis of fcnii-leptonic decays. k ^ ] ~ . - . . m , i had emphasized before that in a state-of-the-art discussion of |v(ub)/v{cb)\ one has to specify the hadronization scheme adopted. i have refrained from doing so in eq. ( ) basically because there is no well-developed such scheme yet for baryonic b decays. all thr parameters a, b, c are rather uncertain. , naive di-quark pictures tend to yield a* < ac\ fa arguments lead to au ~ at and there is no conclusive argument against au > ac even. . resonance effects clearly affect bu,cu in a very significant way. argus observes a low mass enhancement in the px spectra in eq. ( ) which appears consistent with i —* pir. this rases some highly intriguing questions. . it is virtually impossible that a significant part of b° —* ppw+ir" is fed from b° -+ aa modes. * br[&° —> pir~) = ; furthermore it is almost unavoidable that b° +> a++a++, a ~ a ^ . ( ) therefore br(b° -* aa) ~ br(b° - a°a°) = &br(b° -* pp*+k-) ( ) i.e., unacceptably huge! iv. summary a. the presence. over the last few years we have developed a rather decent understanding of charm decays — one that is better than for strange decays. this development has been made possible by the coincidence of three factors: . nature has decided on a fairly undramatic dynamical pattern underlying charm decays. there is no striking feature like the a / = i rule. . there have been good, comprehensive data - the "mark iii legacy.''"' . cloae feed-backs between experimentalists and llwomtx hari ovvrhipwi. yet the success of our theoretical description lias not been firmly cki aid islii'd, improved data could reveal grave deficiencies. beauty physics on tin? other hand i*slill in its adolescent phase, rkiriiclfrizi-d more by promise than completed achievement: we have surlril in draw ;i rough sketch or the overall picture and to extract the i\ m i«w»itih.ets, li. the future. in charm decays i. important cross checks have to be performed, namely fa) sli;dy /)+-° — vv transitions, (b) determine absolute dt branching ratios and (mil hhht of lln-m. (c) do the same for charm baryons. expectation t{b -» nn) > t{b -» a&) ( ) with n-^&r. { ) . a related selection rule can be stated for b+ decays l'{/l + -» a + v ) » l ' { / ' + - • ; add that further experimmtftl input is of crucial iinporlaucc fov mnkiiir progress: (;i) olii-ili the selection ruh-s (|-:«|. u, , t ). (l>) kind or limi!. /*' •-»/i;»st+st"t+. (<) slriti- in identify linal h(;' i*s containing a jr°. (d) mini exclusive modes containing charm baryons like —^ \rnir for (theoretical) calibration purposes. http://cnhanromo.nl references . k. berkelman, these proceedings; i. i. bigi, invited lectures given at the charm physics symposium, beijing, pr china, slac pub- ( ); d. macfarlane, these proceedings; s. stone, these proceedings; m. witliercll, these proceedings; . m. bauer, b. stech and m. wirbel, z- phys. £ ( ) . . d. m. coffman, ph.d. thesis, calt- - . . b. grinstein, n. lsgur and m. wise, phys. rev. lett. g£ ( ) . . a. ah and t. c. vang, phys. lett £sii ( ) . g, for a recent comparison see: b. stcch, invited talk given at the smj miitiato topical seminar on heavy flavors, san miniato, , preprint hd-thep- - . . see for example: h- lipkin, les houcbes lectures ig , c dewitl, v. gillet (eda.), gordon and breach, m. gronau, d. g. sutherland, nucl. phys. g! ^ ( ) . . a. j. butas, j.-m. gerard and il ruckl, nucl. phys. b s ( ) . . b. blok, m. a. sb'rfman, preprints itep- , , ( ). . h. krascroann, phys. lett, b ( ) . . j. adler et al., slac-pub- . . x.-y. l i , x.-q. li and ping wang, preprint as-iip- -q . . g. gladding, these proceedings. . we have to reach a higher level of sophistication in once and twice cabibbo suppressed decays. . all of this should eventually lead to a more precise determination of v(c&), v(cd). in beauty decays we have to . continue to map _.ut b decays and start on the bt, . compare r[bi) vs. t(b mixing with rigor rather than just vigor, and . analyse rare decays and cp violation with considerable more confidence. v. acknowledgements i have benefitted greatly from discussions with s. brodskv, h. harari, y. nir and b. stcch. want to thank the organizers, in particular, e. bloom and a. fritlman, for taking considerate care of mind and body. . h. albrechtet al., preprint oesy - . . m.bigi, phys.l«tt, b( ) lo - h, harari, private communications. . numbers like that have appeared also on the backs of envelopes held by m.gronau, h.harari, j.rosner, m.shifm&n, b.stech and many more, . d. slech, preprint hd-thep- - . - sec also m. gronau, tliese proceedings. . i ii»ve«ini<* to praise mark , not to bury them disclaimer this report was prepared as an account of work sponsored by an agency of the united states government. neither the united states government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or response bility for (he accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. refer ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom mendation, or favoring by the united states government or any agency thereof. the views and opinions of authors expressed herein do not necessarily state or reflect those of the united states government or any agency thereof. �� !�� "�� # �� $��%�� &&&� '�� #�� (�� &&)� �� * +�� &&,� �� -� �� -�� -�� .�� &&/ $�� &&)� '�� -�� -� �� -�� -�� # -�� -�� $�� &&�� '�� -� �� # �� -�� -��-�� --�� -�� '�� &�&� $�� --�� '�� &&�� &&�� - �� -�� -�� -�� -�� -� �� -�� .�� &&�� :�� -�� --�� -�� - �� &�� -�� ;�� :�� -�� - �/� �� ,� �� # +�� -�� <�* �� -�� -�� -�� = �� >�� &&& �� # �� $�� =�� &�< �� < -�� $�+$� .��%�� (�� &&&� = �� - ��-� �� ? 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. if we drop the restriction to sleeping beauty problems where beauty is woken i times if chance hypothesis hi is true, and return to ross’s more general class, the arguments in weatherson ( ) were meant to prove the following two claims, and not a lot more. first day in any sleeping beauty problem where beauty wakes at least one time in every chance hypothesis, and exactly one time in at least one of them, when she wakes the first time, her conditional credences in each hypothesis in s, conditional on this actually being the first waking, equals the objective chance of each such hypothesis. last day in any sleeping beauty problem where beauty wakes at least one time in every chance hypothesis„ when she wakes the first time, her conditional credences in each hypothesis in s, conditional on this actually being the last waking, equals the objective chance of each such hypothesis. since first day entails ( ), and last day entails ( ), these principles entail the / answer. but they don’t settle what to say about the three-day sleeping beauty example. if cr is beauty’s credences when she wakes for the first time in that example, these principles are consistent with beauty having the following credal distribution. cr (today is monday and heads) = / cr (today is monday and tails) = / cr (today is tuesday and tails) = / cr (today is wednesday and tails) = / ross on sleeping beauty but those credences are incompatible with the generalised thirder principle, so first day and last day do not entail that principle. ross ( ) argues that this isn’t right, and that the motivation for first day offered in weatherson ( ) in fact does lead to the generalised thirder principle on its own. i think that’s true in a sense; the argument provides just as much support for the generalised thirder principle as it does for first day. but that’s because it is a bad argument, and doesn’t support first day. we’ll see why that’s true shortly. but since it is true, a new argument is needed for ( ), one that supports first day, but not the generalised thirder principle. most discussions of sleeping beauty assume that the contents of propositional attitudes are sets of centered worlds. following stalnaker ( ), the argument in weatherson ( ) tried to get by with propositions simply being sets of worlds. the key idea was that the worlds themselves would be fine-grained enough that thoughts like hesperus is phosophorus, or today is monday would be contingently true if true at all. very roughly, we associate singular terms with something like fregean senses. when beauty wonders whether today is monday, she isn’t wondering about whether an instance of the law of identity is true. she has no more interest in that law than does the first gentleman of europe. she is wondering, in effect, whether two senses, today and monday, have the same referent. this way of looking at things implies that credal dynamics need to be compli- cated. sometimes our credences change because we acquire more information, and we react accordingly. but sometimes our credences change because we acquire new senses, and we can think new thoughts. that will become crucial in what follows. there is a quick argument for last day. consider what happens after beauty wakes up at the end of the puzzle, and is told that the game is over. (that is, on wednesday in the original puzzle, or on thursday in the three-day variant.) plausibly, her credence in h should be back to / , or at least it is hard to see a good argument why it should be anything else. she can also think back to her last waking, and think to herself if h, that was on monday, and if ¬h, that was on tuesday. (she’ll replace tuesday with wednesday in the three-day variant.) call this conditional c. now think back to that last waking. at that time she is wondering various thoughts about the waking she is currently undergoing, a waking she will describe as “this waking”. when she wakes on wednesday, and thinks about “that waking”, it is plausible she is thinking the very same kind of fregean thought. she is thinking about the same thing, and thinking about it in the same kind of way. if that’s right, then the big difference between her credences after the puzzle ends and her credences on the last in weatherson ( ) these are described as haeceitties, but this is misleading at best. it is crucial that ‘hesperus’ and ‘phosphorus’ have different associations, but intuitively they have the same haecceity. thinking of the associations as being with something like senses is better. one might be tempted by a seemingly stronger argument. for instance, one could argue that on wednesday, beauty knows that the chance of h was / , and she has no inadmissible evidence, so by the principal principle her credence in h should be / . but it isn’t clear that she has no inadmissible evidence; perhaps the evidence she would express by thinking back to her last waking and saying that waking happened is inadmissible. or one might be tempted by a reflection principle based argument against any alternative credence. but such arguments seem to lead to odd results in general around sleeping beauty. it’s best, i think, to stick with the clear intuition that on wednesday her credence in h should be / . ross on sleeping beauty waking are just that she comes to learn c. so on the last waking, her credence in h conditional on c should be / , since when she learns c and nothing else, her credence in h becomes / . and that entails ( ), and similar reasoning generalises to all sleeping beauty problems to entail last day. the argument in weatherson ( ) for ( ), and for first day, involved a rather baroque variant of the example involving time travelers. and, as we’ve noted already, it also involves some fallacious equivocation. before we get to that, it is worth noting two other arguments for the same conclusion, neither of which generalise to the generalised thirder principle. both arguments have contentious premises, but they are somewhat independent, so i hope that presenting both arguments will increase the number of people who agree with firstday. the first argument is an argument from the principal principle. consider the ver- sion of the sleeping beauty puzzle where the coin is tossed after beauty goes back to sleep on monday. (we didn’t say so far when the coin is tossed, and it was consistent with everything we said that it is monday night.) and assume that beauty knows that the coin is tossed monday. so when she wakes on monday, she knows that the chance of h is / if it is monday. that is, cr (ch(h) = / |m) = . the principal principle says that unless beauty has inadmissible evidence, cr (h|cr(h) = / ) = / . and plausibly she doesn’t have any inadmissible evidence conditional on it being monday. putting these two together, we get cr (h|m) = / . and that kind of reasoning generalises to support first day. the argument here is similar to the original argument given for ( ) in elga ( ). elga imagines a variant of the example where beauty is told, sometime after she wakes up, that it is monday, and argues that after that she should have credence / in h, and derives ( ) from that. halpern ( ) objects to this argument on the grounds that the possibility of beauty being told what day it is undermines the indistinguishability of the wakings, and this undermines elga’s own argument for ( ). i’m not sure halpern is right, but in any case, this argument doesn’t rely on any possibility of beauty being told what day it is. i imagine that some people will object to the claim that beauty has no inadmissible evidence. but it is hard to see what she knows which is inadmissible, at least conditional on it being monday. she knows that if it is monday, the truth of h rests on a chance event that is yet to take place, and from which she is causally isolated. that looks to me like knowledge that she has no inadmissible evidence. the second argument is a version of the the technicolor beauty argument in titlebaum ( ). it relies on a variant of the example that drops the idea that the wakings are indistinguishable in a strong sense. i’ll set up first what the idea behind the argument is, and then set out how it works. assume that beauty can think about m on sunday. follow ross in using cr for beauty’s credences on sunday. the same principal principle style argument we used above suggests that cr (h|m) = strictly speaking, all we’ve really shown is that beauty’s credences on the last day she wakes should satisfy last day. so if the focus of the puzzle is on her credences on the first day, all we’ve strictly speaking shown is that if h, then last day is true. i think it is plausible that last day should be independent of how the coin lands, but i admit that i don’t have an argument against someone who wants to dispute this. ross on sleeping beauty / . indeed in this case the argument is even stronger, since everyone agrees that on sunday, beauty has no inadmissible evidence. but nothing happens to surprise beauty between sunday and monday, so cr (h|m) = / should be / as well, and we derive ( ) from there. there are a few problems with this argument. for one thing, the ‘no surprise’ premise goes by very quickly. more importantly, beauty can’t actually have m thoughts on sunday. she can think to herself that monday is monday, or at least she could if she cared to think about the law of identity. but that’s not the same thought as m. remember, the guiding idea here is that contents are fregean; it isn’t easy to have the same thought as someone who thinks this is monday. something dramatic needs to happen to let beauty have such a thought on sunday, when she isn’t in a position to make the same kind of demonstration as she is on monday. here’s one way the dramatic thing might happen. change the example so that the wakings beauty undergoes are not phenomenally indistinguishable. in fact, beauty is told on sunday that each waking will be in a brightly coloured room, and the colours will be different each day. as it happens, the room that will be used for monday is red, though beauty doesn’t know that. let re be the proposition that one of beauty’s wakings will be in a red room, and rm be the proposition that she wakes monday in a red room. now clearly re, on its own, is inadmissible evidence in the sense that cr (h|re) need not be / . after all, re is probabilistic evidence that beauty has more than one waking, since the more wakings she has, the more chance there is that one of them will be in a red room. on the other hand, rm does not look like inadmissible evidence. she has to wake up in some colour room or other on monday; learning it is red doesn’t change anything. so cr (h|rm) should be / . and that’s true even though rm obviously entails re. now she wakes on monday, and the room is red. what follows? well, she now knows re. and she can identify her current waking with the red waking she imagined (or at least could have imagined) on sunday. so it is at least arguable that when on monday she considers the thought this waking is on monday, that’s the very same thought she considers on sunday by saying to herself the waking in a red room is on monday. making that last claim more plausible would require offering a more detailed theory of mental content than i have the space (or ability) to do here. for now i’m just going to take as a premise that there’s a workable theory of mental content that types contents more finely than does a purely referential theory, but on which it is nevertheless the case that beauty’s demonstrative thought on monday has the same content as her descriptive thought (about the waking in the red room) does on sunday. here is one way of thinking about that claim about content that may make it more plausible. (this idea is derived from the arguments in jeshion ( ).) imagine that on sunday beauty names the waking in a red room. she calls it ‘bluey’. she knows that ‘bluey’ might not refer. that is, she knows that bluey, like vulcan and sherlock holmes, might not exist. but she nevertheless entertains detailed thoughts about bluey. she wonders if bluey will be on monday, whether she’ll be happy when bluey happens, and so on. now she wakes up on monday, and sees the red walls. she ross on sleeping beauty says to herself, “this is bluey”. from that point on, it seems that she’d express the same thought with this waking is φ and bluey is φ, and it seems she’s express the same thought with bluey is φ and the waking in a red room is φ. by appeal to transitivity of identity, and substituting a particular value for φ, we get that she expresses the same thought by saying this waking is on monday as by saying the waking in a red room is on monday. if that claim about content is right, then all that happens on monday is that beauty learns that re is true. she doesn’t acquire the ability to think new thoughts, or to make fresh divisions in possibility space, the way that she does in the stan- dard version of the puzzle. in the standard version of the puzzle, the demonstrative thought she considers on monday, the one she would express by saying this is mon- day, is not equivalent to anything she can think on sunday. so when she wakes, she not only acquires some evidence, she acquires a new cognitive capacity. that doesn’t happen here, which makes the calculations easier. in particular, it lets us appeal to the following key fact. if e entails e , and a particular update only involves conditionalising one’s prior credences, then learning e doesn’t change the conditional credence of anything given e . that’s a conse- quence of the following theorem. let pr be any probability function, and let pr+ be the result of conditionalising that function on e . then pr(h|e ) = pr+(h|e ). so if beauty only learns re, that doesn’t change the conditional credence of anything given rm. in particular, it doesn’t change the conditional credence of h given rm. so cr (h|rm) = / . and since m and rm are trivially equivalent, since beauty can see the room is red, it follows that cr (h|m) = / , as required. i suspect the main objection to this argument will be that adding the room colours makes a substantial change to the problem. the fact that / is the correct answer in this technicolour version of sleeping beauty, says the objector, is no rea- son to think that it is also the correct answer in the version where the wakings are phenomenally indistinguishable. but i think the objector will have a hard time mak- ing the case that phenomenal indistinguishability is epistemically significant unless they want to defend what williamson ( ) calls the ‘phenomenal conception of evidence’. as has been pointed out in prior work on sleeping beauty, the different wakings are not evidentially equivalent; when she wakes up and sees that this waking is happening, that’s a piece of evidence she gets in some but not all wakings. (this point is made in weintraub ( ) and stalnaker ( ).) it might well be argued that this demonstrative evidence is in a sense symmetric; although she gets evidence that is different in some sense on the different wakings, the force of that evidence is the same. but that’s still true in the technicolour version of the problem as well. so i think, contra the objector, that this is a good argument for ( ). but neither of those were the argument offered in weatherson ( ). that argument involved a rather baroque modification to the puzzle. a time traveller films beauty waking on monday and travels back to sunday to show beauty the film. after she sees the film, and can think about the waking it depicts, the traveller tells her that he took it on monday. he then wipes beauty’s memories of this telling, but not of the showing of the film. the argument then proceeds as follows. ross on sleeping beauty . on sunday, she can think about her monday waking in the same way as she thinks about it on monday when she wakes, thanks to the time traveller’s film. . on sunday, the rational credence in h is / . . if premise is true, then on monday, after she wakes, the only difference between her epistemic state then and her epistemic state after being told that the film was of monday is that she no longer knows m. . if the only difference between two epistemic states is that in the first, an agent knows m and in the second she does not, then the rational credence of h given m in the second state equals the rational credence of h in the first state. and from that cr (h|m) = / was claimed to follow. now there wasn’t much of an argument for the first premise offered, and it might well be thought objectionable. it certainly relies on a liberal conception of sameness of ‘ways of thinking’. but let’s set that aside, because there is a much bigger problem with the argument. it hopelessly equivocates on the phrase ‘on sunday’. let’s distinguish the following four times that are all on sunday. • t is before the time traveller turns up. • t is immediately after the time traveller shows beauty the film. • t is immediately after the time traveller tells beauty that the film is of monday. • t is after the time traveller wipes beauty’s memories of that telling, but not of the showing of the film. now let’s consider the first two premises in weatherson’s argument. the first premise is clearly false if ‘on sunday’ refers to t , but arguably true if it refers to t , t or t . the second premise is clearly true if ‘on sunday’ refers to t , but much less plausible if it refers to any later time. if it refers to t or t , it is arguably equivalent to the / answer to the original sleeping beauty problem, which makes it pretty useless in an argument for the / answer! if it refers to t , it is much too close to what we’re trying to prove in arguing for firstday, so it is still argumentatively useless. ross argues that the style of argument we’ve been considering would, if it showed that ( ), and indeed more generally supported first day, would show much more. in fact, it would show that for any two chance hypotheses hi and hj, and any k such that hj is consistent with at least k wakings, that the following is true. (i’ll again use pkj to mean that this is the k’th waking and hj is true.) cr (p i|(p i ∨ pkj)) = ch(hi) ch(hi) + ch(hj) and from that we can derive the generalised thirder principle, and hence count- able additivity violations. that wasn’t what was intended; the argument was only designed to work for the special case where k = , i.e., first day. now i think ross is right in the following sense; there’s just as good an argument in weatherson ( ) for the above equation as there is for first day. but that argument is no good for the reasons described above. let’s see where the same equivocation comes into ross’s telling of the story. i’ve changed ross’s notation a fair bit into notation i find easier ross on sleeping beauty to work with. hopefully i haven’t lost anything in the process. i’m also going to focus on the special case of three-day sleeping beauty, where h is the coin lands heads and h is the coin lands tails, and on the case where k = . so what we’re really going to look at is whether there’s an argument in three-day sleeping beauty for this equation. cr (p |(p ∨ p )) = ch(h ) ch(h ) + ch(h ) = now as noted above, i think that this equation need not hold in three-day sleeping beauty; in the model i gave for it earlier, cr (p ) = / , and cr (p ) = / , so cr (p |(p ∨ p )) = / . but let’s see how ross derives the / answer. again there is a time-traveller who shows beauty a film. but this isn’t necessarily a film of the first waking; the time traveller films the first waking if h , and the second waking if h . after seeing the film, beauty is told this. so on sunday, says ross, beauty’s credences should satisfy these constraints. (i’m following ross in using cr for the sunday credences.) cr (h ) = cr (h ∧ p ) cr (h ) = ch(h ) there are other premises used, but these will be the crucial ones. they’re crucial because there’s no good reason to think that there’s any time sunday when beauty’s credences should satisfy both these equations. before she sees the film, she can’t even think about propositions like p , since she can’t have singular thoughts about the waking it depicts. after she sees the film, there is no reason to think that her credences should align with chances. causal contact with a time traveller who brings information that may well be about a time after the chance event, evidence whose existence may depend on the outcome of the chance event, is pretty much paradig- matically inadmissible evidence for the purposes of the principal principle. so after the film, there is no reason to think cr (h ) = ch(h ). i should stress that ross doesn’t endorse the equivocating premises here; he merely attributes them to weatherson ( ), and fairly so. but i think once we see the equivocation we can see there is no fear the kind of argument used in weatherson ( ) will lead to the generalised thirder principle. that argument is too flawed to lead to anything. but there are plenty of other arguments for first day, such as the two arguments offered here. and both of those arguments rely on distinctive features of the first day. most notably, they rely on the fact that for all we say in the setup of the problem, the first waking is before the chance event. so there’s no reason to think they will have the problematic consequences that ross finds in the argument for first day in weatherson ( ). references elga, adam, ( ). “self-locating belief and the sleeping beauty problem.” analysis : - , doi: . /analys/ . . . ( ) http://dx.doi.org/ . /analys/ . . ross on sleeping beauty halpern, joseph, ( ). “sleeping beauty reconsidered: conditioning and re- flection in asynchronous systems.” in oxford studies in epistemology, volume , - . oxford: oxford university press. ( ) jeshion, robin, ( ). “acquiantanceless de re belief ’.” in joseph keim camp- bell, michael o’rourke, and david shier (eds.), meaning and truth: investigations in philosophical semantics, - . new york: seven bridges press. ( ) ross, jacob, ( ). “sleeping beauty, countable additivity, and rational dilem- mas.” philosophical review : - , doi: . / - - . ( ) —, ( ). “all roads lead to violations of countable additivity.” philosophical studies : - , doi: . /s - - -z. ( , ) stalnaker, robert, ( ). our knowledge of the internal world. oxford: oxford university press. ( , ) titlebaum, michael, ( ). “the relevance of self-locating beliefs.” philosoph- ical review : - , doi: . / - - . ( ) weatherson, brian, ( ). “stalnaker on sleeping beauty.” philosophical studies : - , doi: . /s - - - . ( , , , , , , , ) weintraub, ruth, ( ). “sleeping beauty: a simple solution.” analysis : - , doi: . /analys/ . . . ( ) williamson, timothy, ( ). the philosophy of philosophy. blackwell. ( ) http://dx.doi.org/ . / - - http://dx.doi.org/ . /s - - -z http://dx.doi.org/ . / - - http://dx.doi.org/ . /s - - - http://dx.doi.org/ . /analys/ . . ross on sleeping beauty () ar x iv : . v [ he p- ph ] s ep beautiful mirrors for a pngb higgs eduardo c. andrés, leandro da rold, iván a. davidovich centro atómico bariloche, instituto balseiro and conicet av. bustillo , , s. c. de bariloche, argentina abstract we consider one of the most significant deviations from the standard model: the forward-backward asymmetry of the b-quark measured at leptonic colliders. we investigate the possibility to solve this discrepancy by introducing new physics at the tev scale. we focus on models where the higgs is a pseudo nambu-goldstone boson of a new strongly coupled sector with a global so( ) symmetry broken spontaneously to so( ). besides the usual top partners, we introduce bottom partners in the representations and of so( ) and show that they can improve significantly the fit by correcting the zbb̄ couplings. we also estimate the corrections to the couplings at one-loop and obtain that the tree-level ones dominate and can give a reliable estimation. we find that the large shift required for zbrb̄r leads to light custodians associated to the b-quark, similar to the top partners, as well as a rich phenomenology involving neutral interactions in the bottom-sector. http://arxiv.org/abs/ . v introduction the recent discovery of a light scalar field, with a mass around gev and similar properties to the standard model (sm) higgs boson, has deep implications in our understanding of elec- troweak symmetry breaking (ewsb) [ , ]. the negative results in the search of new particles with masses m . tev at the first lhc-run introduces some tension for theories beyond the standard model (bsm) aiming to solve the little hierarchy problem. one of the most interest- ing possibilities to alleviate this problem is a higgs arising as a pseudo-nambu goldstone boson (pngb) of a new strongly interacting sector at a few tev scale [ ]. in this scenario the higgs potential is generated radiatively through the interactions with the sm fields, that explicitly break the non-linearly realized global symmetry protecting the higgs potential, leading to a separation between the scale of the resonances of the strongly coupled field theory (scft) and the electroweak (ew) scale. besides, the contributions of the fermions to the potential, par- ticularly those associated to the top, are misaligned with the original vacuum and can trigger ewsb. although it has been shown that these theories still require some amount of tuning [ ], they remain as one of the most promising bsm avenues. there are different patterns of symmetry breaking that one can consider to obtain a higgs as a pngb. a very interesting approach is the minimal composite higgs model (mchm) based on so( )-symmetry. as first shown in ref. [ ], so( )×u( )x is the minimal symmetry group that contains the ew gauge symmetry of the sm as well as a custodial symmetry and can deliver a higgs as pngb. assuming that the strong interactions of the scft spontaneously break so( ) to so( ), a nambu golstone boson (ngb) emerges with the proper quantum numbers to be associated with the sm higgs. several incarnations of the so( )/so( ) symmetry breaking pattern have been considered in the literature. as examples, there are realizations in warped [ , ] and flat extra-dimensions [ , ], as well as theories with collective breaking or deconstruction, theories with two [ , ] and three sites [ ], that can be thought of as discretized descriptions of extra dimensional models. one of the main difficulties for composite higgs models is to pass electroweak precision tests (ewpt). generically these theories induce corrections to the sm interactions at tree level that can bee too large to pass these stringent tests. besides the well known oblique corrections, one important problem is the correction to the zblb̄l coupling, that has been measured very precisely, such that the corrections can not be larger than the per mil level compared with the sm. in models where the bsm sector has a global o( ) symmetry spontaneously broken to the custodial o( ) after ewsb, it has been shown that the zblb̄l coupling can be protected by the presence of a subgroup of o( ). assuming that the interactions between the sm and the bsm are linear in the sm fields, also known as partial compositeness: lint = ψsmoψscft , ( ) this symmetry is realized if the scft operators coupled to the sm doublet ql transform as ( , ) / under su( )l×su( )r×u( )x [ ]. this way, despite the large mixing between the resonances of the scft and ql, required to obtain the top mass, to leading order there are the u( )x factor is required to account for the proper normalization of hypercharge. no corrections to zblb̄l. moreover, when considering a pngb higgs arising from so( ), the previous assignment of quantum numbers restricts the so( ) representations of the operator oqscft to include a ( , ), the smallest representations satisfying this condition are , and [ , , ]. on the other hand, lep and sld measurements of the forward-backward asymmetry in the production of bb̄: abfb, suggest deviations of the coupling zbrb̄r compared with the sm. a solution to this anomaly can be achieved by the introduction of new vector-like fermions with the proper quantum numbers, often called beautiful mirrors [ ]. in the framework of composite higgs models, these fermions can be associated to excitations created by the operator obscft. ref. [ ] showed the expected sign in the shift of the zbrb̄r coupling for some representations of obscft under su( )l×su( )r×u( )x. refs. [ , ] proposed an effective two-site model with two resonances mixing with the bottom sector, one transforming as ( , )− / that induces the proper correction to zbrb̄r, and another one transforming as ( , )− / that after small mixing with bl gives a small positive correction to zblb̄l, preferred by a b fb. the presence of both multiplets also allows to write a proto-yukawa term in the sector of resonances, that can lead to the mass of the bottom quark through partial compositeness. refs. [ , ] have proposed similar solutions. recently ref. [ ] performed a fit of the sm taking into account the latest theoretical and experimental results. it shows significant deviations from the sm in zbb̄ couplings that are attributed to deviations in abfb at . σ. the fit points to δg/g corrections of o( %) for the right-handed coupling correlated with a ∼ % correction of the left-handed one. motivated by the discovery of a light higgs-like particle and the deviations in the zbb̄ couplings, we want to consider an extension of the model of ref. [ ] where the higgs could be realized as a pngb. we will consider an effective two site model with the higgs arising from the well known so( )/so( ) pattern of symmetry breaking. to obtain a finite one-loop potential we will embed all the fermion and vector resonances into full so( ) multiplets [ ]. to generate the proper corrections of the zbb̄ couplings we will consider bottom partners embedded in so( ) representations containing a ( , ) and a ( , ) multiplet of su( )l×su( )r. the smallest representations of so( ) with these properties are the and ; these will be the uplifted beautiful mirrors. to be able to generate the top mass and trigger ewsb we will also introduce top partners. for simplicity we will consider them transforming with the representation of so( ). in sec. we describe our model and compute the zbb̄ couplings at tree level in the mass basis. in sec. we show the effective theory at energies much lower than the scale of the composite-resonances and obtain the couplings at zero momentum. in sec. we compute the higgs potential arising from the specified set of representations. in sec. we give our numerical results after demanding dynamical ewsb as well as the proper spectrum for the light states corresponding to the sm degrees of freedom. in sec. we discuss the one-loop corrections to the zbb̄ couplings. in sec. we give a brief description of some interesting properties of the model for the phenomenology at accelerators and we conclude in sec. . a model to solve the deviation in abfb and a light higgs ref. [ ] considered theories with a new scft with global symmetry su( )l×su( )r×u( )x. it showed that if the sm fields interact linearly with the scft, eq. ( ), in order to protect the zblb̄l coupling from large corrections in the presence of a large mixing between ql and an operator oqscft, the new sector must have a plr symmetry exchanging su( )l and su( )r, and oqscft must be embedded in the ( , ) / representation of the extended symmetry. in this case the interaction between bl and the corresponding component of oqscft preserves plr and the coupling zblb̄l is protected. on the other hand refs. [ ] and [ ] showed that δgbr can be positive if br mixes with an obscft in a ( , )− / and [ ] also showed that δgbl can be positive if ql mixes with a second operator oq b scft in a ( , )− / . by extending the symmetry of the new sector to so( )×u( )x, the higgs can be a pngb arising from the spontaneous breaking of so( ) to so( ). the interactions between the scft and the sm fields explicitly break the global symmetry and generate a potential for the higgs at loop level. this potential can induce a misalignment of the vacuum and trigger ewsb dynamically. explicit realizations of this pattern of symmetry breaking [ , , , , , , ] have shown that to obtain a finite higgs potential at one loop the oscft must be embedded in full representations of the global symmetry. in the present work we are interested in the representations and of so( ) for the fermionic operators oq b scft and obscft, respectively, since they contain a ( , ) and ( , ) multiplets of su( )l×su( )r, and therefore the interac- tions of this operators with the bottom quark can induce the proper shifts of the zbb̄ couplings to solve the deviations pointed to in ref. [ ]. these operators also have the proper quantum numbers to generate a bottom yukawa interaction. there are larger so( )-representations containing the multiplets of su( )l×su( )r speci- fied previously and there are also larger su( )l×su( )r-representations that can achieve shifts in the zbb̄ couplings with the correct sign [ ], however the and are the smallest represen- tations once so( ) is chosen; in this sense we will work in a minimal model. these operators can create fermionic resonances, the lowest lying levels of those with masses of order tev, that we will call beautiful mirrors. to be able to generate the top mass by partial compositeness and trigger ewsb we also introduce an operator oq t scft in a representation of so( ), we use the index q t to distinguish it from the one involved in the generation of the bottom mass that has index qb. we will add an operator otscft interacting with tr, and for simplicity we will assume that o qt scft and otscft transform with the representation . we could choose other representations for these operators, but we do not expect that the physics we want to study could have a relevant dependence on this choice. . -site description a d effective description of an scft leading to resonances, similar to qcd but with a scale of order tev, can be realized in a theory with two sites [ ]: one site called site- with elementary fields and another one called site- with fields that describe, at an effective level, the first layer of composite resonances of the scft. in this work we will consider a two site theory very similar to the models of refs. [ ] and [ ], with the difference that we will introduce representations for the fermions not considered in those articles. we will closely follow the notation of ref. [ ]. we will use lower case letters for the fields of site- and capital letters for the fields of site- . the elementary sector at site- contains the same fermionic and gauge degrees of freedom as the sm but no elementary scalar: l = − g w̃ j lµνw̃ j µν l − g ′ b̃µνb̃ µν + iψ̄ d ψ , ( ) where a sum over the sm fermions is understood, j = , , and w̃ j l and b̃ are the su( )l and u( )y gauge fields, respectively. d µ is the covariant derivative containing the fields of the elementary sector. the tilde over the gauge fields denotes the non-canonical normalization of their kinetic terms. there is also an su( )c gauge symmetry that we have not written because it does not play any role in our analysis. it is very convenient to introduce new spurious degrees of freedom in the elementary sec- tor [ ], such that the sm gauge symmetry is extended to so( ) ×u( )x, the same group as in the composite sector, with hypercharge realized as y = t r + x. the spurious fields are not dynamical and they do not play any physical role. the fermions can also be extended to fill complete representations of this group. we will introduce two chiral elementary fermions called qt and qb, respectively transforming as / and − / . under su( )l×su( )r these multiplets decompose as: ∼ ( , ) ⊕ ( , ) and ∼ ( , ) ⊕ ( , ) ⊕ ( , ) ⊕ ( , ). the ( , ) / and the ( , )− / contain each just one / of su( )l×u( )y , whereas the other so( ) multiplets do not contain a / . out of these two doublets only one linear combination will be dynamical. by defining p / as the projector that acting on the space of the fields embedded in full so( ) multiplets project them onto the subspace containing a / , the dy- namical doublet can be written as ql ≡ p / (qt + qb), all the other components will be just spurious fields. we will also promote tr to a / , with the ( , ) / component being the only dynamical field. we will embed br in a − / , using that ∼ ( , )⊕( , ), the only dynamical field will be the up component of the ( , )− / . in terms of these multiplets the elementary lagrangian reads: l = − g ãcµνã cµν − g x x̃µνx̃ µν + iψ̄ d ψ , ( ) where now the sum is over ψ = qt,qb, t and b, c is an index in the adjoint of so( ): c = , . . . . the elementary hypercharge coupling is g′− = g − + g − x and the dynamical field is obtained by setting w̃ r = x̃ = b̃. for more information on the representations of so( ) used in this paper see ap. a. the composite sector at site- contains an so( ) ×u( )x gauge symmetry, as well as several fermions charged under this symmetry. we will assume that the so( ) symmetry is sponta- neously broken to so( ) at a scale f by the strong dynamics of site- . we will parametrize this breaking by considering a non-linear description in terms of a unitary matrix u , containing the ngb fields arising from the spontaneous breaking: u = e √ iΠ /f , with Π = Π â t â and t â the broken generators of so( ) /so( ) . the so( ) symmetry is non-linearly realized, since under a transformation at site- : g ∈ so( ) : u → g u h (g ; Π )†, with h (g ; Π ) ∈ so( ) implicitly depending on g and Π , as usual in the ngb formalism [ ]. the lagrangian of the bosonic sector at site- is: l ⊃ − g ρ ãcµνã cµν − g x x̃µνx̃ µν + f dâµdµâ ( ) with c = , . . . and ã and x̃ being the so( ) and u( )x gauge fields, respectively. dâµ is implicitly defined by u † d µu = ieaµta + dâµt â, with d µ the covariant derivative containing the fields of the composite sector. we take the couplings of site- to be larger than the sm couplings, but still in the perturbative regime: gsm ≪ gρ ≪ π, where by gρ we generically denote all the couplings of the composite sector. for the fermions of the composite sector we will consider four vector-like multiplets: two associated to the top and transforming as / , called q t and t , and two associated to the bottom, one called qb transforming as − / and another one called b transforming as − / . besides the usual kinetic and mass terms, there are also yukawa interactions involving the ngb field Π . the lagrangian of the fermions at site- is: l ⊃ Ψ̄(i d − mΨ)Ψ + ∑ r ytrpr(u † q t l)pr(u † tr) + ∑ r ybrpr(u † q b l)pr(u † br) + h.c. ( ) where a sum over Ψ = qt,qb,t and b is understood. r is an irreducible representation of su( )l×su( )r, pr is a projector from the space of representations of so( ) to the subspace of the r representation of su( )l×su( )r and the product pr(Φ′)pr(Φ) corresponds to the usual operation leading to an su( )l×su( )r invariant. we have considered only a partial set of chiral structures, not including for example terms of the form pr(u † Ψl)pr(u † Ψr), neither of the form: pr(u † q t r)pr(u † tl) or pr(u † q b r)pr(u † bl). as argued in ref. [ ], those operators introduce divergences in the higgs potential at one-loop, unless one goes to three or more sites [ , ]. for the yukawa interactions of the top sector there is a trivial singlet, independent of Π [ ], that leads to a mass mixing term between q t and t and can be obtained by taking yt( , ) = yt( , ). there is also a non-trivial invariant proportional to yt( , ) − yt( , ). for the bottom sector there are two non-trivial independent invariants, with couplings yb( , ) and one can consider also an su( ) gauge symmetry in the composite sector to describe resonances of the gluons. for simplicity, and because we will be concerned with the ew sector only, we will not mention them anymore in this work. it is also usual to write the invariants by working with the ngb vector field Φ = u Φ , with Φ t = ( , , , , ) parametrizing the so( )/so( ) vacuum before ewsb. in this case the invariants for the yukawa interactions can be written formally as: Ψ̄lΦ nΨ′r, with n = for Ψ, Ψ ′ ∼ and n = , for Ψ ∼ and Ψ′ ∼ . refs. [ , ] used the later parametrization to write the yukawa interactions. yb( , ). the presence of more than one yukawa structure in the down sector in general leads to flavor violating processes mediated by higgs exchange that, in anarchic models, are too large compared with the present bounds on flavor violating interactions [ ]. by imposing a plr symmetry under the exchange of su( )l and su( )r one obtains: yb( , ) = yb( , ). in a theory of flavor this symmetry aligns the bottom yukawa structures in flavor space and relaxes the most stringent constraints arising from those processes [ ]. in the following we will assume that yb( , ) = yb( , ) ≡ yb. notice that the yukawa couplings as defined in eq. ( ) are dimensionful. we expand the neutral yukawa interactions in terms of the components within each multiplet in ap. b. the elementary and composite sectors described above are coupled by non-linear σ-model fields Ω and Ωx, realizing partial compositeness. the non-linear σ-model fields transform bilinearly under the elementary and composite symmetry groups: Ω → g Ωg† and similarly for Ωx. as a consequence, there is mixing between the elementary and composite fields, and the mass eigenstates are a superposition of both sectors. each non-linear σ-model field is characterized by an energy scale, fΩ and fΩx . the mixing lagrangian is: lmix = f Ω tr|dµΩ| + f Ωx |dµΩx| + q̄lΩ (∆qtΩ / x q t r + ∆qbΩ − / x q b r) + ∆t t̄rΩΩ / x tl + ∆bb̄rΩΩ − / x bl + h.c. ( ) the link field Ω parametrizes the coset so( ) × so( ) /so( ) + , with so( ) + the diagonal subgroup of so( ) × so( ) , and similarly for Ωx Ω = e √ iΠΩ/fΩ , Ωx = e √ iΠΩx /fΩx , ( ) where ΠΩ = Π c Ω t c − and t c − are the generators of the coset. the covariant derivatives contain in this case elementary and composite gauge fields, as required by gauge invariance: dµΩ = ∂µΩ − iãµΩ + iΩãµ , dµΩx = ∂µΩx − ix̃µΩx + iΩxx̃µ . ( ) . mass eigenstate basis to make contact with the physical content of the theory one can go to the unitary gauge by performing a gauge transformation g = Ω and g x = Ωx. after that the only physical scalars can be parametrized by u = e √ iΠ/fh , Π = hât â , f h = f Ω + f . ( ) after ewsb the vacuum is described by the parameter: ǫ = sin v fh , ( ) with v = 〈h〉 and h = hâhâ. to better understand the particle content and the different sources of symmetry breaking of the theory, we briefly discuss the spectrum as well as its modifications when the different sources of mixing are taken into account. freezing the elementary fields one can study the spectrum of the pure composite sector. it contains vectors in the so( ) subgroup with mass mρ = gρfΩ/ √ , vectors in the so( ) /so( ) coset with mass mâ = gρ √ f Ω + f / √ and a vector of u( )x with mass mx = gxfΩx/ √ . after the mixing between the two sites, there remains a gauge symmetry su( )l, + × u( )y, + , corresponding to the diagonal subgroups. the corresponding massless gauge fields are linear combinations of elementary and composite gauge fields w il = cθ w i l + sθa i l , i = , , ; b = b + tθ′ρa r + tθ′xx ( + t θ′ρ + t θ′ x ) / , ( ) where we have rescaled the gauge fields as: wil = g w̃ i l, b = g ′ b̃, a c = gρã c and x = gxx̃. we have also used shorthand for the trigonometric functions: cα ≡ cosα, sα ≡ sinα and tα ≡ tanα, and the different mixing angles: θ,θ′ρ and θ ′ x are respectively given by: tθ = g /gρ , tθ′ρ = g ′ /gρ , tθ′x = g ′ /gx . ( ) the couplings of the gauge fields defined in eq. ( ) are given by: g = g + g ρ , g′ = g ′ + g ρ + g x . ( ) the orthogonal combinations to eq. ( ) correspond to massive fields. the spectrum of heavy vectors arising from this diagonalization is slightly modified with respect to the original mass, but the corrections are small as long as tθ ≡ g /gρ ≪ , as was assumed to be the case. as an example, for ρ̃il = cθa i l − sθwil the mass is mρ̃ = mρ √ + t θ. the masses of the composite fields that do not mix with the elementary ones remain unchanged. for more details on the precise linear combinations and spectrum of the massive states we refer the reader to ref. [ ]. after ewsb the spectrum is further modified, the w and z bosons obtain masses: mz ≃ √ g + g′ ǫfh/ and mw ≃ gǫfh/ , where one can identify: vsm = gev ≃ ǫfh . the masses of the heavy states are slightly modified after ewsb, which induces mixing between the heavy states as well as mixing with the light ones. as a summary, there are seven neutral states: one massless and another light one, corresponding to the photon and z, and five heavy states; there are also four charged states: a light one corresponding to the w , and three heavy states. since the mixing angles are small, the light states are mostly elementary and the heavy states are mostly composite. the fermionic mixing can also be diagonalized by performing a rotation of the chiral components involved in lmix. we define fermionic mixing tθΨ ≡ tanθΨ = ∆Ψ/mΨ, with Ψ = qt,qb,t,b. after the corresponding rotation there is a set of chiral fermions that remain massless, their degree of compositeness measured by θΨ. the masses of the fermions corre- sponding to the orthogonal combinations become mΨ̃ = mΨ √ + t θΨ. the masses of the fermions that do not mix, often called custodians, remain being mΨ. for large mixing angles, as is the case for the mixing leading to the top mass and mildly for the mixing of br leading to the shift in the coupling zbrb̄r, there can be a sizeable separation between the scales mΨ̃ and mΨ. by fixing the scale mΨ̃ ∼ mρ̃ ∼ o( - )tev, for mixing sθΨ & . , one obtains light custodians with masses . tev [ , ]. after ewsb all of the fermions with the same elec- tromagnetic charge are mixed. in the present model there are nine up-type fermions, eleven down-type fermions and some exotic fermions: two with q = + / , eight with q = − / and two with q = − / . one up-type fermion and one down-type fermion become massive only after ewsb, they are lighter than the other states and correspond to the top and bottom. in ap. b we show the mass matrices for these fermions. although the mass matrices can be diagonalized straightforward numerically, it is worth obtaining the analytic diagonalization expanding in some small parameter. by this procedure one can obtain analytic expressions for the couplings in the mass basis and understand the size and sign of the corrections as functions of the fundamental parameters of the theory. we have considered a perturbative expansion in powers of ǫ, obtaining a full diagonalization of the fermionic and bosonic sectors to o(ǫ ). since the mass matrices of the up- and down-type quarks are of dimension and , and the mass matrix of the neutral vector bosons is of dimension [ ], the explicit expressions for the eigenvalues and eigenvectors are too long to be written in the paper. however in the next subsection we will show our results for the zbb̄ interactions using this perturbative diagonalization. . zbb̄ interactions in the mass eigenstate basis we compute the zbb̄ interactions in the basis of mass eigenstates. in order to do that we have diagonalized the bosonic and fermionic mass matrices perturbatively in ǫ, the first non-trivial correction being of o(ǫ ). since the z is a mixing between the elementary and composite neutral vector fields, there is a universal correction to the z couplings. that correction remains for vanishing fermion mixing and therefore is the same for all fermions. we have subtracted that term in the results that we present in eq. ( ), such that we only show the non-universal corrections. in order to simplify the equations, for the correction to zblb̄l we have set ∆b = , whereas for zbrb̄r we since ql mixes simultaneously with one doublet contained in q t and another doublet contained in qb, the diagonalization of this system is more involved, requiring the angles θqt and θqb. the squared masses of the massive states emerging from the diagonalization, in the absence of yukawa terms, can be written in the following way: (m q̃t + m q̃b ) ± [(m q̃t + m q̃b ) − m q̃t m q̃b ( + t θ qt + t θ qb )( + t θ qt )− ( + t θ qb )− ] / . have set ∆qb = , obtaining: δgmassbl = g cw ǫ f h m qt m t∆ qb + m qb [m qt m t + ∆ qt (m t + y t( , ) )] { −∆ qtm qb(m t + y t( , )) [ g − g′ m ρ + g′ m x ] +∆ qbm qtm t [ g ( + t− θ ) − g′ m ρ + g′ m x + y b( , ) f hm b ]} , δgmassbr = g cw ǫ f h m qb m b + ∆ b(m qb + y b( , ) ) ∆ b { g′ m x (m qb + y b( , )) + y b( , ) + y b( , ) f h + m ρ [ g ( + t− θ )(m qb + y b( , )) − g′ (m qb + y b( , )) ] } . ( ) the gauge couplings appearing in eq. ( ) were defined in eq. ( ). we have checked that the relative difference between these approximations and the full numerical results are ∼ % for the points selected in our scan (see details in the next sections). we analyse first the left-coupling. notice that, when considering the interaction between mass-eigenstates, this coupling is modified by the mixing with the fermion qt even for ∆qb = , the correction being of order δg/g ∼ −g ǫ ∆ qt/ g ρm qt. compared with the naive estimate in the absence of plr- symmetry [ ], this contribution is suppressed by a factor g /g ρ. this term is present because the mass eigenstates are mixtures of elementary and composite fields, therefore they do not have well defined transformation properties under the full gauge symmetry group. the correction arising from the mixing with qb can be split in two: one mediated by a heavy vector, of order δg/g ∼ ǫ ∆ qb /m qb , where we have taken into account the fact that g/gρ ∼ tθ, and another one involving the bottom yukawa, of order ∼ ǫ ∆ qb y b( , ) /m qb m b. although the corrections mediated by ∆qb are suppressed by a small mixing compared with those mediated by ∆qt, the large couplings of the composite sector can compensate that suppression, mainly with the term proportional to t− θ . also notice that the contribution from mixing with q t is negative, whereas the contribution from mixing with qb is positive, as expected from the representation under so( ) chosen for this fermion. the presence of a negative contribution to δgmassbl requires a mixing ∆qb larger than expected to compensate the negative term and obtain a positive δgmassbl . the correction to the right-coupling in the mass basis is positive and is controlled by the mixing with b. it can also be enhanced by large composite couplings. low-energy effective theory we consider in this section the effective theory at energies lower than the scale of resonances. this is particularly useful when studying the zbb̄-interactions, because one can gain under- standing on the different symmetries that can protect the couplings, as well as on the origin of the sources that break those symmetries and induce corrections to the couplings. the ef- fective theory also provides a very compact formalism to describe the spectrum and therefore to compute the higgs potential at one-loop. we proceed by integrating-out the states of the composite sector, obtaining an effective theory for the elementary ones. the gauge sector has the same symmetries and field content as ref. [ ], where the effective lagrangian for the gauge fields was computed in detail. below we show the main results that are needed for the purposes of this article and in ap. c we show the gauge correlators in the so( )-symmetric vacuum. the quadratic effective lagrangian for the gauge fields arising from integrating-out the composite vectors is: leff ⊃ ∑ r Πar pr(u †aµ) pr(u †aµ) + Πxxµx µ , ( ) with r being so( )-representations and u acting on the representation of so( ). the correlators Πar can be computed straightforward by integrating out the composite vectors in the so( )-symmetric vacuum ǫ = . although we are using a different parametrization of the pngb field compared with ref. [ ], where it was parametrized in terms of a vector in the fundamental of so( ), both descriptions coincide. by considering an arbitrary vacuum and keeping only the elementary gauge fields of su( )l×u( )y , we obtain: leff ⊃ ∑ i= Πwi l w̃ilµw̃ iµ l + Πw l b w̃ lµb̃ µ + Πb b̃µb̃ µ , ( ) where the correlators Πwi l , Πb and Πw l b can be expressed in terms of the correlators Π r a and Πx as: Πwi l = Πa( , )+( , ) + (Πa( , ) − Πa( , )+( , )) sin ( v fh ) , Πb = Π x + Πa( , )+( , ) + (Πa( , ) − Πa( , )+( , )) sin ( v fh ) , Πw l b = − (Πa( , ) − Πa( , )+( , )) sin ( v fh ) . ( ) at quadratic level in the elementary fermions, the most general effective lagrangian arising from integrating-out the composite states of our two-site model can be written as: leff ⊃ ∑ ψ=qt,qb,t,b ∑ r pr(u†ψ) p Πψr pr(u†ψ) + ∑ ψ=t,b ∑ r pr(u†qψ) m ψ r pr(u †ψ) + h.c. ( ) with u acting on the so( )-representation corresponding to each fermion. the correlators Πψr and mψr can be computed straightforward by considering the so( )-symmetric vacuum ǫ = . for a general vacuum, and keeping only the dynamical fields, eq. ( ) leads to [ ]: leff ⊃ t̄l p(zq + Πtl)tl + b̄l p(zq + Πbl)bl + t̄r p(zt + Πtr)tr + b̄r p(zb + Πbr)br + t̄lmttr + b̄lmbbr + h.c. ( ) where zψ are the kinetic terms of the elementary fermions. the correlators of the dynamical fermions can be expressed in terms of the ones in the so( )-symmetric vacuum as: Πtl =α ( , ) tl,q t(h)Π qt ( , ) + α ( , ) tl,q t(h)Π qt ( , ) + α ( , ) tl,q b(h)Π qb ( , ) + α ( , ) tl,q b(h)Π qb ( , ) + α ( , ) tl,q b(h)Π qb ( , ) + α ( , ) tl,q b(h)Π qb ( , ) , Πbl =α ( , ) bl,q t(h)Π qt ( , ) + α ( , ) bl,q t(h)Π qt ( , ) , + α ( , ) bl,q b(h)Π qb ( , ) + α ( , ) bl,q b(h)Π qb ( , ) + α ( , ) bl,q b(h)Π qb ( , ) + α ( , ) bl,q b(h)Π qb ( , ) , Πtr =α ( , ) tr,t (h)Πt( , ) + α ( , ) tr,t (h)Πt( , ) , Πbr =α ( , ) br,b (h)Πb( , ) + α ( , ) br,b (h)Πb( , ) , mt =β ( , ) t (h)m t ( , ) + β ( , ) t (h)m t ( , ) , mb =β ( , ) b (h)m b ( , ) + β ( , ) b (h)m b ( , ) , ( ) where the functions α and β can be obtained by computing the invariants in an arbitrary vacuum. for those related with the top quark we obtain: α ( , ) tl,q t(h) = ( + c h) , α ( , ) tl,q t(h) = s h , α ( , ) tl,q b(h) = , α ( , ) tl,q b(h) = , α ( , ) tl,q b(h) = c h , α ( , ) tl,q b(h) = s h , α ( , ) tr,t (h) = s h , α ( , ) tr,t (h) = c h , β ( , ) t (h) = chsh√ , β ( , ) t (h) = − chsh√ , whereas for those related with the bottom-quark: α ( , ) bl,q t(h) = , α ( , ) bl,q t(h) = , α ( , ) bl,q b(h) = s h s h , α ( , ) bl,q b(h) = c h − c h − ch − , α ( , ) bl,q b(h) = c h c h + ch + , α ( , ) bl,q b(h) = s h c h − ch + , α ( , ) br,b (h) = s h , α ( , ) br,b (h) = c h , β ( , ) b (h) = i √ s h sh , β ( , ) b (h) = − √ ( + ch)sh . ( ) in the previous expressions we have used the following shorthand notation cnh ≡ cos ( n h fh ) and similarly for snh. the correlators in the so( )-symmetric vacuum expressed in terms of the parameters of the model are shown in ap. c. following ref. [ ] we define: v sm = Πw l( ) = f hǫ , g = g + Π′ w l ( ) = g + g ρ − ǫ g ρ f ( f Ω + f ) (f Ω + f ) , g′ = g ′ + Π′b( ) = g ′ + g ρ + g x − ǫ g ρ f ( f Ω + f ) (f Ω + f ) , ( ) where Π( ) ≡ Π(p )p = . the matching of eq. ( ) implies that in the effective theory, at zero momentum the corrections to the gauge interactions are mediated by the mixing with the heavy fermions, such that, for zero fermionic mixing the coupling is sm-like. we will show the explicit results for the z interactions in the effective theory in sec. . . . z-interactions in the low energy effective theory in this section we compute the z-interactions in the effective theory. since the elementary and composite fields have well defined transformation properties under the gauge symmetry groups and the effective theory is formulated in terms of the elementary fields after integrating-out the composite ones, the symmetries of the model are manifest in the low energy effective theory. in particular, we expect the symmetries protecting several couplings to manifest explicitly in this basis; we will show below that this is the case. we will consider the couplings at p = . we begin by analysing the interactions with the top quark. since tr transforms as ( , ), from pc symmetry [ ] we expect the tr coupling to be protected. we have checked that property by explicit calculation, finding no corrections. on the other hand the tl coupling is not protected. in eq. ( ) we show our result. although it is possible to obtain the coupling to all orders in ǫ, for simplicity in the presentation we only show the leading order terms. the bl coupling can receive contributions from the mixing with q t and qb, the first po- tentially large due to the large ∆qt required by the top mass. however, since the composite fermion in qt mixing with bl has t l = t r = − / , a plr symmetry protects this coupling from corrections induced by mixing with qt [ ]. on the other hand, the mixing with qb induces a positive shift of the bl coupling, suppressed by the small ∆qb mixing that controls the bottom mass [ ]. notice that it is positive and is suppressed by ǫ ∆ qb /m qb . the shift of the br coupling is positive and controlled by ∆ b. to leading order in ǫ we obtain: δgefftl = g cw ǫ { − ∆ qtm qb [ f Ω ( yt( , ) − yt( , ) ) + f ( m t + y t( , ) − yt( , )yt( , ) + y t( , ) ) ] + ∆ qbf m qtm t } { (f Ω + f ) [ m qtm t( m qb + ∆ qb) + m qb∆ qt(m t + y t( , )) ]}− + o(ǫ ) , δgefftr = , δgeffbl = g cw ǫ ∆ qb m qtm t [ f m b + y b( , ) (f Ω + f ) ] m b(f Ω + f ) [ m qt m t ( m qb + ∆ qb ) + m qb ( m t + y t( , ) )] + o(ǫ ) , δgeffbr = g cw ǫ ∆ b f Ω ( y b( , ) + y b( , ) ) + f ( m qb + y b( , ) + y b( , ) ) (f Ω + f ) [ m bm qb + ( m qb + y b( , ) ) ∆ qb ] + o(ǫ ) . ( ) the weinberg angle has been defined by the usual tree-level relation, with the couplings g and g′ defined in the effective theory by eq. ( ). by comparing these effective couplings with the couplings between the mass eigenstates one can appreciate the size of the corrections, the most important one being the contribution to δgbl arising from mixing with q t that is present in the basis of mass eigenstates, but is not present in the effective lagrangian thanks to the plr-symmetry. for non zero momentum the z-interactions become form factors with non trivial momentum dependence. these corrections also give rise to new lorentz structures [ ], as: pµ p, p′µ p, pµ p ′, p′µ p′, γµ p, γµ p′, with pµ and p′µ the momentum of the particle and antiparticle. note that the last two structures flip chiralities. higgs potential two site models lead to a one-loop higgs potential that is finite and calculable, provided that one excludes certain chiral structures in the yukawa interactions [ , ], as detailed in sec. . we assume that the light generations have small mixing for both chiralities and therefore do not have a large impact in the one-loop higgs potential. the effect of the other states are fully taken into account. using the correlators of the effective theory, the higgs potential at another possibility would be to allow for all the possible chiral structures in a model with at least three sites [ ]. one loop can be written as [ , ]: v (h) = ∫ d p ( π) { ∑ i= log ( p g + Πwi l ) + log [( p g + Πw l )( p g ′ + Πb ) − Π w l b ] − nc ∑ ψ=t,b log [ p (zψl + Πψl)(zψr + Πψr) − |mψ| ] } . ( ) notice that we have included the kinetic terms in the expression for the potential because they were not included in the definitions of the correlators. the fermionic correlators are proportional to the mixing squared, Πl,r ∝ ∆ l,r and m ∝ ∆l∆r. thus we expect fermions with large mixing to dominate the potential. the top quark requires large mixing with the composite sector to account for its large mass. the mixing explicitly breaks the symmetry behind the ngb nature of the higgs, thus the top quark usually dominates the higgs potential. a large correction to zbrb̄r also requires a considerable mixing of br, with a potentially important effect in v (h). however, for yb( , ) = yb( , ) as in the present model, the correlator Πbr is independent of h. the reason is that in this limit the only invariant involving just br is the trivial one. as we will discuss in the next sections, the mixing of bl is smaller than those of the top and br, therefore we expect the effect of the bottom quark in the higgs potential to be subleading in the present model. for h = there is a divergent contribution to the higgs potential that has no impact on ewsb. a finite and meaningful potential can be obtained by computing v (h) − v ( ). numerical results one of the goals of this article is to obtain the shift of zbb̄ couplings in the region of the parameter space of the model where the ew symmetry is broken and the masses of the sm fields are around their physical values. to satisfy these conditions we have performed a random scan over the parameters of the model, selecting the proper points. below we describe the implementation of the random scan and after that we present our results for the couplings. we have followed a similar procedure to the one of ref. [ ]. we have scanned over the bosonic mixing tθ and tθx ≡ tanθx = gx/gx. for simplicity we have imposed the relation tθ = tθx , that fixes the ratio between elementary and composite couplings to be the same for the different groups. we have fixed the remaining freedom in the set of gauge couplings by matching with the sm couplings, as shown in eq. ( ). we have expressed the decay constants of the σ-model fields in terms of the masses of the vectors mρ̃ and the higgs decay constant fh, and we have scanned over them. the choice tθ = tθx leads to gx ∼ . gρ, thus to avoid a light vector resonance arising from the u( )x symmetry we have considered fΩx ∼ fΩ. for the fermions we have scanned over the mixing tθΨ, with Ψ = q t,qb,t and b. we have also expressed the composite masses mΨ in terms of the masses mΨ̃ (see the discussion in the paragraphs below eq. ( )). for simplicity we have fixed mΨ̃ = mρ̃, the same value for all the representations, however notice that even under this simplifying assumption there can be large splittings between the different fermions due to the suppression of the masses of the custodians when the mixing is large. besides we have also scanned over the yukawa couplings of the composite sector: yt( , ),yt( , ) and yb( , ) = yb( , ). concerning the numerical values, we have allowed large ranges for all the parameters. how- ever we present results constrained to some regions of the parameter space, motivated by phe- nomenological considerations. we let the bosonic mixing vary according to: tθ ∈ [ . , . ], we have allowed small values for this parameter because they favour larger shifts in the z cou- plings. we have considered sθqt,sθt ∈ [ . , ) for the top, sθqb ∈ [ . , . ] and sθb ∈ [ . , . ]. for fh we scanned over fh ∈ [ . , . ] tev, the smallest value corresponding to ǫ ∼ . for vsm = gev, of the order of the maximum value allowed by ewpt. for the masses of the resonances we have allowed mρ̃ ∼ − tev, that is consistent with the approximate relation mρ ∼ gρfh, with gρ in the range determined by the bosonic mixing angle detailed before. we have considered real yukawa couplings within the nda perturbative regime: |y/fh| ≤ π. for each point we have evaluated the one-loop higgs potential, as well as the masses of the higgs, the z boson, the top and bottom. we have normalized all the dimensional parameters by demanding the mass of the lightest neutral boson to reproduce the sm z mass, and we have only kept the points that match the sm values for the other masses. the phenomenology that we have studied is not very sensitive to small variations around the central values of the masses, therefore, due to the finite time for cpu calculation, we have considered the following ranges: . mh . gev, . mt . gev and . mb . gev. we have also discarded points with ǫ > . as well as points with masses of bosonic vector resonances below tev. after selecting the points that satisfy these conditions, we have computed the couplings by performing a numerical diagonalization. we have checked our analytic formulas by comparing with the results obtained by the procedure already described. in fig. we show δgbl and δgbr for the points of the scan that pass the selection conditions detailed in the previous paragraph, as well as the % and % probability distributions for these shifts from ref. [ ]. the white cross shows the center of the ellipses. first, one can see that there are many points that can solve the discrepancy attributed to the deviation in abfb. second, the probability distributions of ref. [ ] present a strong correlation between both shifts, such that shifting just one of the couplings does not improve the fit considerably. instead the probability distributions prefer a shift δgbl ∼ o( − ) correlated with a shift δgbr ∼ o( − ). in order to shift both couplings simultaneously, considerable mixing sθqb and sθb are required, as shown in eqs. ( ). in that case, in order to reproduce the bottom mass, since the same mixing that controls the shift of the couplings also controls the mass of the bottom quark, the composite bottom yukawa coupling yb( , ) has to be suppressed to compensate the effect of the mixing and lead to a small bottom mass. on the other hand, if the composite bottom yukawa coupling is large, of the same size as the other composite couplings, at least the mixing of one of the chiralities has to be small to suppress the mass, leading to a very small shift for the coupling associated to that chirality. this behaviour is ++ ææ æ æ æ æ æ ææ æ æ æ æ æææ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ æ æ æ æ æ æ æ æ æ ææ ææ æ æ æ ææ æ æ æ æ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ ææ æææ æ æ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ æ æ æ ææ æ æ æ æ æ æ æ æ æ æ æ æ æ æ æ æ æ ææ ææ æ æ æ æ æ æ æ æ æ æ ææ æ ææ æ ææ æ æ æ ææ æ æ æ ææ æ ææ æ æ æ æ æ æ ææ æ æ æ ææ æ ø øø ø øø ø øø ø ø ø ø ø ø ø øø ø øø øø ø ø ø ø ø øø ø ø ø ø ø ø øøø ø ø ø ø øø ø ø ø ø ø ø ø ø ø ø ø ø ø ø øø øøø ø ø ø ø à à à à à à à à à à à à à à à à à à à àà à à àà à à à àà à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à àà à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à àà à à à à à àà à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à àà à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à àà à à à à à à à à àà à à à à à à à à à àà àà à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à à àà à à à àà à à à ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò òò ò ò ò ò ò ò ò ò ò ò òò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò òò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò òò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò òò òò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò ò - . . . . . . . . δ g b l δgbr figure : results for the shifts in the zbb̄ couplings. the ellipses correspond to the % (dark region) and % (light region) probability distribution for δgbl and δgbr from ref. [ ], the white cross shows the center of the ellipses. the black points (dots) have bottom yukawa coupling: yb/fh ∼ gρ and one small bottom mixing, typically the left-handed one. the colored points (stars, squares and triangles) have sizeable sθ qb and sθb, and small bottom yukawa coupling: yb/fh ∼ o( − ). the colors codify the value of ǫ: orange points (stars) for ǫ ∈ ( , . ), green points (squares) for ǫ ∈ ( . , . ) and red points (triangles) for ǫ ∈ ( . , . ). present independently of the nature of the composite higgs, whether it is a pngb or not and is instead associated to partial compositeness, and has been noticed before in scenarios where the higgs was not a pngb [ ]. that behaviour is shown in fig. , where the black points (dots) correspond to regions of the parameter space where the yukawa is large: yb/fh ∼ gρ, whereas colored points (stars, squares and triangles) correspond to regions of the parameter space with sizeable sθ qb and sθb, and small bottom yukawa coupling: yb/fh ∼ o( − ), introducing a little hierarchy between the composite couplings. this yukawa violates the assumption that gρ ≫ gsm for all the composite couplings. the colors codify the value of ǫ: orange points (stars) for ǫ ∈ ( , . ), green points (squares) for ǫ ∈ ( . , . ) and red points (triangles) for ǫ ∈ ( . , . ). as expected, since to leading order in ǫ the shift is proportional to ǫ , a large shift requires ǫ & . . we have not found points that satisfy all the selection criteria specified before and produce corrections that lie outside of the range shown in the plot. the previous results introduce at least two different scales: one for the yukawa of the top sector and another one for the yukawa of the bottom sector. still, since we have considered only the third generation of quarks, the present analysis does not give any information about the flavor structure of the yukawa couplings and composite masses. that issue is beyond the scope of this work. g Ψ(n) h,g i b b̄ figure : radiative correction to zbb̄ at -loop in the gaugeless limit, g /i is the neutral/charged ngb associated with the longitudinal degree of freedom of the z/w i and Ψ(n) is a heavy fermionic resonance. radiative corrections to zbb̄ we have shown the tree level corrections to zbb̄ interactions, however it is important to estimate the size of the one-loop contributions, to test the stability of the corrections. in particular, the large mixing of some of the fermions can have an impact on the small correction allowed for zblb̄l. ref. [ ] has considered the one-loop correction to this interaction in models with so( )/so( ) symmetry breaking pattern, computing the contributions from fermions in the representation / . the authors argued that when there are several multiplets present in the theory, in large regions of the parameter space ewpt can be satisfied, particularly a shift of gbl small enough is obtained. there are some simplifications in the case / because there is no br partner in the composite sector and also because the heavy down-type quarks, the quarks with charge q = − / , arise from multiplets with the same quantum numbers under su( )l×u( )y as the sm doublet: / . since in our model there are quarks with exotic hypercharge assignments as well as large mixing for br, it is worth performing an estimation of the one-loop corrections in the present case. we take the gaugeless limit for our calculation, which has been shown before to yield good predictions while simplifying the calculations greatly [ ]. the zbb coupling will thus be estimated by calculating the g bb coupling, where g is the ngb eaten by the z. by taking this limit, we are left with the diagram shown in fig. . this diagram can be split into various contributions corresponding to corrections to g blbl and g brbr and to fermions Ψ (n) of charges − / (v-type quarks), − / (down-type quarks) or / (up-type quarks) running in the loop. this diagram represents a finite contribution to the g bb coupling which can be explicitly calculated for all fermions running in the loop. details on the expressions obtained for this diagram can be found for example in [ , ]. performing a numerical calculation for different sets of points in the parameter space of our model we arrive at the following results. we find that the shift to the g blbl coupling produced by considering only the charge / fermions running in the loop, subtracting the sm contribution, is of order δgbl|t ∼ − . similarly, δgbr|t is of order ∼ − . the difference with the ngb in the loop changing accordingly to maintain conservation of electric charge in the vertices. in size for these shifts can be readily understood by considering a perturbative expansion in both the fermionic mixing and the yukawa couplings with the ngb’s. for δgbl|t , we would expect the main perturbative contribution to be proportional to s θqt y t lt , where lq is the loop factor coming from the phase space integration with the q-type quarks running in the loop. this is due to the fact that the elementary bl has a non-zero projection on an elementary which, after mixing with the composite , can couple directly to a top-like fermion through the yukawa coupling with the charged ngb’s. on the other hand, the br field is embedded in a which contains no charge / fermions and which must undergo various mixing and yukawa couplings before being able to mix with the top-like fermions. in particular, it mixes with the elementary ql so it can then follow a path similar to the one explained for the bl. hence, we expect the largest contribution to δgbr|t to be ∼ s θby bs θ qb y t lt . in order to get the right mass for the sm b quark the product (sθ qb sθbyb) needs to be small, thus δgbr|t is suppressed with respect to δgbl|t . a large tree level shift to the zbrbr coupling typically requires sθb large, then in this case the suppression in δgbr|t/δgbl|t is of order s θ qb y b/y t . similarly, we can compare the shifts produced by the top-like quarks with those produced by the charge (− / ) quarks. for the v-type quarks, we find δgbl|v ∼ − . this is orders of magnitude smaller that δgbl|t , which is consistent with the fact the the main perturbative contribution to it is expected to be ∼ s θ qb y blv and thus heavily suppressed with respect to δgbl|t . on the other hand, the main perturbative contribution to δgbr|v ∼ s θby blv , resulting in δgbr|v ∼ − which is of the same size as δgbr|t ; in this case, the difference in loop factors, yukawa couplings and fermionic mixing roughly compensates. there is also a contribution due to bottom-type quarks running in the loop (together with a neutral ngb), which can be analyzed in a similar way, and whose size is negligible compared to that of the up-type quarks contribution. it is worth mentioning that due to the nonlinear coupling of the ngb’s in our model and the mixing of b-type quarks, other feynman diagrams can be constructed. some examples are diagrams modifying the self energy of the bottom [ ] and diagrams arising from -fermion operators [ ]. in some cases these diagrams can be divergent and must be renormalized. phenomenology at colliders we briefly discuss the phenomenology of the model at colliders as the lhc. similar to other realizations of a higgs as pngb of so( )/so( ), we expect light fermionic resonances also known as custodians with charges q = + / , / and − / ; these are usually present in models based on representations / , / and / . in the present model, the representation − / leads also to resonances with new exotic charges q = − / , whereas the − / leads to resonances with q = − / and − / . the masses of the former can have considerable suppression compared to mρ, due to the non-negligible mixing sθb ∼ . , whereas for the later they are expected in the same range as mρ, since the suppression of their masses is small as long as sqb is not so large. moreover, for small composite yukawa in the bottom sector, the mirror fermion in − / contains three rather light custodians that are almost degenerate and, under su( )l×u( )y , have the following quantum numbers: one doublet − / and one singlet − / . similarly, in this limit the − / contains a set of almost degenerate custodians generically heavier than the previous ones, that under su( )l×u( )y can be organized as: − / , − / , − / , two − / doublets, / , − / and − / . for the points shown in fig. we find that generically the br custodians have masses similar to the custodians of the top. the production and detection of exotic resonances associated to br would be a distinctive signature of this kind of models. refs. [ , ] have explored this scenario, selecting the single production of states with q = − / and proposing a search strategy at lhc, see also [ ] for a very comprehensive analysis. the present model provides a complete framework to study the phenomenology of these exotic resonances given the presence of a light higgs. there can also be interesting signals associated to the neutral interactions between the sm b quark, a down-type fermionic resonance b(m) and a neutral vector boson, either the sm z or a resonance z(n), with m = , . . . and n = , . . . , the indexes ordered by increasing mass. the different processes to create one of this resonances and its dominating decay channel depend on the spectrum and the size of the couplings. although there are many different possibilities and the spectrum and couplings can change much as the parameters of the theory vary, we want to discuss some general situations that can be expected in the present type of scenarios. after that we will describe the generic properties of the spectrum and couplings that can lead to these processes. first, if the coupling zb(m)b̄ is large, b(m) can be produced (either qcd production b(m)b̄(m) or single ew production) and decay to zb, leading to a final state where one could fully reconstruct the b(m)-mass by selecting a visible z-decay channel. in the case of z(n) heavier than b(m), if z(n) is produced it can decay via z(n) → b(m)b̄, and eventually to zbb̄ if the coupling zb(m)b̄ is large enough. in this case the full process would be ψψ̄ → z(n) → b(m)b̄ → zbb̄, with bottom quarks and z of large pt and with the eventual possibility to reconstruct the full mass of z(n) and b(m). in the case of production of b(m) heavier than z(n), a very interesting decay would be a cascade of neutral decays like b(m) → z(n)b → b(ℓ)b̄b → zbb̄b, again with final states with large pt . let us now briefly discuss the spectrum of down-type fermionic resonances and neutral vector bosons. we expect two light custodians: one arising from the multiplet / mixing with tr and another one from the multiplet − / mixing with br. there are also five custodians from the − / , usually with larger masses than the previous ones since the bl mixing is smaller than the other mixing, as well as three more states with no mass suppression: one from the / mixing with ql, one from − / and another from the − / . in our scan, after taking into account ewsb effects, we have found a splitting between two sets of resonances: two light resonances mostly given by the first two custodians described in the beginning of this paragraph, and eight heavier resonances. for the neutral vectors we find three states with similar masses mostly arising from the neutral components of so( ) and from u( )x, and two heavier states mostly from the coset so( )/so( ). we also find that the heavier set of fermions have masses similar to the lighter set of bosons. it should be noted, however, that this mass ordering is only a consequence of the fact that we have assumed we consider the strength of the coupling z(n)b (m) l/r bl/r; we call these couplings g nm bl/r . in what follows, we will always refer to the size of the couplings in units of g cw . we use the points with low composite yukawa coupling presented in fig. as a testing ground. we analyse first the right-handed couplings of z( ). we find that typically g br ∼ o( ), with b ( ) usually slightly heavier than z( ), although the mass difference is small in this case and the ordering can be changed easily. another relevant z( ) coupling is that of g br, which can be as large as . but can also fluctuate all the way down to negligible strength, depending on the value of sθ qb . contrary to b( ), b( ) is generally lighter than z( ), but again the splitting is small. z( ) behaves in the same way as z( ) when considering right-handed couplings. z( ) and z( ) both present couplings of strength ∼ . with b( )r br and b ( ) r br . no other right-handed coupling is as relevant as these for the z resonances. for the left-handed chirality there is not a z( ) coupling that is consistently large, but all of b( ),b( ),b( ) and b( ) show couplings of o( ) for a large portion of the points we studied. b( ) has approximately the same mass as z( ) for our region of parameter space. z( ) and z( ) show the same qualitative behavior as z( ) when it comes to couplings with b ( ) l bl and b ( ) l bl. z( ), however, also shows a consistently large coupling with b ( ) l bl (we find it of o( ) for all the points considered). for our points, the mass of b( ) is only ∼ . − . times that of z( ). the left-handed couplings for the heavier z(n) resonances are not, in general, as relevant as these. lastly, we can consider the zb (m) l/r bl/r couplings. out of these, none of the left-handed couplings are relevant. for the right-handed chirality, on the other hand, the two lightest b(m) resonances can exhibit a coupling half as large as that of the sm br quark (see footnote ). conclusions we have presented a model with a naturally light higgs, arising as a pngb of an scft, and able to induce a shift in the zbb̄ couplings that can relax the tension in abfb measured at lep/sld. the model is based on the breaking so( )/so( ) and on the presence of composite fermions associated to the bottom sector transforming with the representations and of so( ). these representations allow to generate the appropriate pull in the zbb̄ couplings and simultaneously to produce the small bottom mass. the top partners are embedded in a , such that no large corrections are induced for zblb̄l in the presence of large mixing for the top, these mixing trigger ewsb and generate the large top mass. we have computed the corrections to the zbb̄ couplings at tree level by performing a per- the mass scale of the gauge bosons and all fermions to be the same; this could be easily altered by introducing different scales for the resonances. what actually seems to happen here is that there is only one b-type “light” quark which has a large coupling, but depending on the values of the parameters considered it will be either the lightest or the second lightest down-resonance. the same appears to be true for these two when it comes to left-handed couplings. turbative diagonalization of the mass matrices expanding in powers of ǫ = sin ( v fh ) . we have obtained analytic expressions for δgbl and δgbr that allowed us to understand the origin, the sign and the size of the different contributions to these corrections. we have also studied the effective theory at energies below the scale of the heavy resonances. by integrating-out the composite-states we have obtained an effective lagrangian for the elementary-states and the higgs. in particular we have computed the zbb̄ and ztt̄ couplings using this procedure, which has the virtue that the symmetry properties of the different sectors become evident. under certain assumptions, the class of models considered in our work has a finite higgs potential at one-loop, that has been computed for fermions in different representations of so( ). in the present article we have included in the calculation of the higgs potential the contributions of all the fermions and vector bosons, including those arising from the bottom sector that transform with the representations and , that can be important if the mixing between that quark and the heavy states are large. by performing a random scan we have found the regions of the parameter space where the ew symmetry is broken and the higgs and the quarks of the third generation have the observed masses. we have also computed the full corrections to zbb̄ couplings at tree level numerically for those regions of the parameter space. we have checked that our analytic results are in very good agreement with the full numerical ones, with higher order corrections smaller than % level. we have found a considerable region of the parameter space of our model where the zbb̄ couplings are corrected in such a way that they can solve the deviation attributed to abfb. the model has been designed to produce those corrections, but we have found that generically, for composite bottom yukawa couplings yb ∼ gρfh, the bottom mass and the correct shifts δgbl and δgbr can not be produced simultaneously. this is expected since there is a strong correlation between the shifts δgbl and δgbr arising from the experimental results. instead we have found that δgbr requires a rather large mixing of br and its composite partners, as was expected, but also δgbl requires a moderate mixing of bl and its partners. since the shift δgbl preferred by the experiments is small, one would have expected that a small mixing could be enough. however when going to the mass eigenstate basis, there is a correction to gbl arising from the top sector, even in the case of plr-symmetry, that although being suppressed, has the wrong sign. therefore, to compensate this correction, the bl mixing has to be somewhat larger than expected from a naive analysis. since the mixing driving the corrections to zbb̄ also control the bottom mass, the composite bottom yukawa has to be partially suppressed to lead to a light bottom. we have checked numerically that this is indeed the case, obtaining yb/fh ∼ o( − ), introducing a small hierarchy between yb and the other composite couplings gρ that we take of order gsm ≪ gρ ≪ π. we have also estimated the corrections to the zbb̄ couplings at one-loop in the gaugeless limit. we found that these corrections are at least one order of magnitude smaller than the tree level ones. therefore we can expect the tree level corrections to give a reliable estimation of the shifts of the zbb̄ couplings. we found an interesting collider phenomenology involving the beautiful mirror fermions. finding exotic fermions with charge − / or − / would provide good evidence for the solution we have presented. there is also a rich phenomenology involving neutral interactions, with the possibility of cascade decays mediated by z- and b-resonances, and possible final states with several bottom quarks and z with large pt . acknowledgements we thank elisabetta furlan and josé santiago for clarifications on their calculation of the corrections to zbb̄ at one loop and elisabetta furlan for sharing with us her codes. we also thank diptimoy ghosh for useful discussions and for having pointed us to ref. [ ]. l.d. wishes to thank the department of particle physics and astrophysics at weizmann institute of sciences for hospitality during a stage of this work. l.d. and i.d. are partly supported by foncyt-argentina under the contract pict- - and u.n.cuyo under the contract . -c . a representations of so( ) for a comprehensive description of the and representations of so( ), refs.[ ] and [ ] should be consulted. here we will present the representation of so( ) in more detail. given the size of the matrices needed to represent the generators of the algebra for this representation, and the fact that most of the elements of these matrices are zeroes, we will describe them by their diagonals. for that purpose, we define diag(g,k) as the k-th diagonal of the matrix representing the element g of the so( ) algebra. k = will be the main diagonal and we will use positive numbers to denote diagonals above the main one and negative numbers for those below it. as an example, if we consider the matrix, mex =   a a a b b b c c c   , ( ) then, diag(mex, ) = (a ,b ,c ) , diag(mex, ) = (a ,b ) , diag(mex, ) = (a ) , diag(mex, − ) = (b ,c ) , diag(mex, − ) = (c ) . ( ) we now proceed to define the generators of the so( ) algebra for the as follows: diag(t l, ) = ( , − , , , , − , , , − , − , , , , − , , − ) diag(t r, ) = ( , , , , , , , , , , − , − , − , − , − , − )    diag(t+l , ) = ( √ , , , , , , , , , , , , , , √ ) diag(t+l , ) = ( , , , , , , − √ , √ , , , , , , ) t−l = t +† l                diag(t+r , ) = ( − , , , , , , , , , ) diag(t+r , ) = ( , , , , − √ , , , , − ) diag(t+r , ) = ( , , √ , , , √ , , ) diag(t+r , ) = ( , , , √ , , , ) t−r = t +† r          diag(t+−, − ) = ( , , , √ , , √ , − √ , , , , , ) diag(t+−, − ) = ( , − √ , , , − , − √ , , √ , √ , √ , , − √ , ) diag(t+−, − ) = ( , √ , , , √ , , , , , − , , , √ , ) t−+ = t+−†                diag(t++, ) = ( √ , , , , , , , , , , , , − √ ) diag(t++, ) = ( √ , , − √ , , − √ , , , , , √ , − , − √ ) diag(t++, ) = ( , , − √ , , − , , √ , √ , √ , , ) diag(t++, ) = ( , , , − √ , , , − , , , ) t−− = t++† ( ) all elements not explicitly indicated are zeroes. the set {t l,t+l ,t − l ,t r,t + r ,t − r } generates the so( ) algebra that is left unbroken after the so( )→so( ) breaking. as is well known, the reason for choosing the usual su( ) naming convention for the generators of this sub-algebra is that so( )≃su( )l×su( )r. on the other hand, {t+−,t−+,t++,t−−} are the broken generators corresponding to the so( )/so( ) coset, that transform as a ( , ) of so( ). the first (second) ± super-index of these generators stands for the ± / eigenvalue under t l (t r). the basis we have chosen to describe these matrices is a basis of eigenvectors of t l and t r (as can be readily seen by the fact that their matrices are diagonal) which are also eigenvectors of the casimir operators, (t l) + (t l) + (t l) and (t r) + (t r) + (t r) . below we show our notation for the components of the fermions corresponding to the different representations of so( ), with charges under su( )l×su( )r given by the previous generators: ψ = (b ,v ,b,v ) , ( ) ψ = ( − i√ (x − b), √ (x + b), i√ (t − t), √ (t + t), t̃ ) , ( ) ψ = (t,b,t ,b ,b ,v ,b ,b ,v ,v ,b ,v ,v ,s ,v ,s ) . ( ) this notation will become useful to describe a basis for the mass and yukawa matrices of appendix b. b yukawa interactions and mass matrices in this appendix we show the neutral yukawa terms and the mass matrices for the up- and down-type fermions. the neutral yukawa terms involving the and representations are: lbyuk = yb( , ) [ − ( bbr ch + ibb ,r sh )( − ( ch + c h )b qb ,l + + sh (−( + ch)bq b ,l + √ ( √ cth b qb l − b qb ,l + cth b qb ,l + + √ b qb ,l) sh) ) + ( ( ch + c h )v qb ,l + sh (−( + ch)v q b ,l + + √ (− √ v qb ,l + cth v qb ,l + v qb ,l + √ cth v qb ,l) sh) )( ish v b ,r + + ch v b ,r )] + yb( , ) [( bb ,r ch + ibbr sh )( ( ch + c h )b qb ,l + + sh ( √ c h b qb ,l − √ c h b qb ,l − b qb ,l − chb qb ,l + + √ b qb l sh + √ b qb ,l sh) ) + ( ( ch + c h )v qb ,l + + sh ( √ c h v qb ,l − √ c h v qb ,l + v qb ,l + chv qb ,l + + √ v qb ,l sh + √ v qb ,l sh) )( ch v b ,r + ish v b ,r )] + h.c. ( ) as usual, t l/r = t + l/r + t − l/r and t l/r = −i(t + l/r − t − l/r ) in the last expression ctnh = cot( nh fh ), and as usual cnh = cos( nh fh ) and snh = sin( nh fh ). the neutral yukawa terms involving the representations are: ltyuk = yt( , ) [ cht̃ qt l − sh√ (t qt l + t qt ,l) ][ cht̃ t r − sh√ (ttr + t t ,r) ] + + yt( , ) { b qt l b t r + x qt l x t r + ( t qt l − t qt ,l ) ( ttr − tt ,r ) + + [ ch√ ( t qt l + t qt ,l ) + sht̃ qt l ][ ch√ ( ttr + t t ,r ) + sht̃ t r ] } + + h.c. ( ) we can calculate a lr matrix for the quadratic terms of the b sector at zero momentum from the lagrangian, using the basis { bl,b b ,l,b b l ,b qb l ,b qb ,l,b qb ,l,b qb ,l,b qb ,l,b qb ,l,b t l,b qt l } and { br,b b ,r,b b r,b qb r ,b qb ,r,b qb ,r,b qb ,r,b qb ,r,b qb ,r,b t r,b qt r } , mb lr =            ∆qb · · · ∆qt −mb · · · ∆b −mb · · · ( y b × ) ... ... ...... · · · −mt · · · yt( , ) −mqt            . ( ) where the main diagonal is ( , −mb, −mb, −mqb, −mqb, −mqb, −mqb, −mqb, −mqb, −mt , −mqt) and the yukawa sub-matrix for the b sector, y b × , is y b × =            √ (−iyb( , ) + yb( , ))s h − √ (yb( , ) − iyb( , ) + (yb( , ) + iyb( , ))ch)sh √ (iyb( , ) + yb( , ) + (−iyb( , ) + yb( , ))ch)sh √ (yb( , ) + iyb( , ))s h i (−yb( , ) + iyb( , ) + (yb( , ) + iyb( , ))ch)sh ( (yb( , ) − iyb( , ))ch + (yb( , ) + iyb( , ))( + c h))√ (−iyb( , ) + yb( , ))s h − √ (yb( , ) − iyb( , ) + (yb( , ) + iyb( , ))ch)sh ( (iyb( , ) + yb( , ))ch + (−iyb( , ) + yb( , ))( + c h)) (yb( , ) − iyb( , ) + (yb( , ) + iyb( , ))ch)sh − √ (iyb( , ) + yb( , ) + (−iyb( , ) + yb( , ))ch)sh − √ (yb( , ) + iyb( , ))s h            . ( ) in a similar fashion, using the basis { tl,t t l ,t t ,l, t̃ t l ,t qb l ,t qb ,l,t qt l ,t qt ,l, t̃ qt l } and { tr,t t r ,t t ,r, t̃ t r ,t qb r ,t qb ,r,t qt r ,t qt ,r, t̃ qt r } , we obtain for the top sector: mt lr =               ∆qb −∆qt −mt −mt ∆t −mt −mqb −mqb ( y t × ) −mqt −mqt −mqt               . ( ) where y t × is given by: y t × =    ( yt( , )( + c h) + yt( , ) s h ) ( yt( , ) − yt( , ) ) s h ( yt( , ) − yt( , ) ) ch sh√ ( yt( , ) − yt( , ) ) s h ( yt( , )( + c h) + yt( , ) s h ) ( yt( , ) − yt( , ) ) ch sh√ ( yt( , ) − yt( , ) ) ch sh√ ( yt( , ) − yt( , ) ) ch sh√ yt( , ) c h + yt( , ) s h    . ( ) now, for the exotic quarks in the model, we begin by considering the v-type quarks with the basis { v b ,l,v b ,l,v qb ,l,v qb ,l,v qb ,l,v qb ,l,v qb ,l,v qb ,l } and { v b ,r,v b ,r,v qb ,r,v qb ,r,v qb ,r,v qb ,r,v qb ,r,v qb ,r } , and obtain: mv lr =      −mb · · · −mb · · · ( y v × ) ... ... −mqb      . ( ) where the main diagonal is (−mb, −mb, −mqb, −mqb, −mqb, −mqb, −mqb, −mqb) and all off- diagonal elements are zero except for the × sub-matrix y v × , y v × =            √ (−iyb( , ) + yb( , ) + (iyb( , ) + yb( , ))ch)sh − √ (yb( , ) − iyb( , ))s h√ (iyb( , ) + yb( , ))s h √ (yb( , ) + iyb( , ) + (yb( , ) − iyb( , ))ch)sh ( (−iyb( , ) + yb( , ))ch + (iyb( , ) + yb( , ))( + c h)) − (yb( , ) + iyb( , ) + (yb( , ) − iyb( , ))ch)sh − √ (−iyb( , ) + yb( , ) + (iyb( , ) + yb( , ))ch)sh √ (yb( , ) − iyb( , ))s h (−iyb( , ) + yb( , ) + (iyb( , ) + yb( , ))ch)sh ( (yb( , ) + iyb( , ))ch + (yb( , ) − iyb( , ))( + c h)) √ (iyb( , ) + yb( , ))s h √ (yb( , ) + iyb( , ) + (yb( , ) − iyb( , ))ch)sh            . ( ) for the s-type (charge - / ) quarks, using the basis { s qb ,l,s qb ,l } and { s qb ,r,s qb ,r } , we get: ms lr = [ −mqb −mqb ] . ( ) and finally, for the x-type (charge / ) quarks, we use the basis { x qt l ,x t l } and { x qt r ,x t r } and obtain: mx lr = [ −mqt yt( , ) −mt ] . ( ) c correlators in this appendix we show the correlators obtained after integration of the composite states of our model at tree level. the correlators obtained from integration of the heavy vector bosons are: Πa( , ) = Π a ( , ) = p m ρ g ρ(p − m ρ) , Πa( , ) = m ρ(p + m ρ − m â) g ρ(p − m â) , Πx = p m x g x(p − m x) . Πa( , )+( , ) ≡ Πa ( , ) + Πa ( , ) . ( ) the correlators arising from integration of qt and t are: Π qt ( , ) = ∆ qt m t − p + y t( , ) m qt (m t − p ) + p (p − m t − y t( , )) , Π qt ( , ) = ∆ qt m t − p + y t( , ) m qt (m t − p ) + p (p − m t − y t( , )) Πt( , ) = ∆ t m qt − p + y t( , ) m qt (m t − p ) + p (p − m t − y t( , )) , Πt( , ) = ∆ t m qt − p + y t( , ) m qt (m t − p ) + p (p − m t − y t( , )) , mt( , ) = ∆qt∆t mqt mt yt( , ) m qt (m t − p ) + p (p − m t − y t( , )) , mt( , ) = ∆qt∆t mqt mt yt( , ) m qt (m t − p ) + p (p − m t − y t( , )) . the correlators arising from integration of qb and b are: Π qb ( , ) = Π qb ( , ) = ∆ qb m qb − p , Π qb ( , ) = ∆ qb m b − p + y b( , ) m b(m qb − p ) + p (p − m qb − y b( , ) ) , Π qb ( , ) = ∆ qb m b − p + y b( , ) m b(m qb − p ) + p (p − m qb − y b( , ) ) , Πb( , ) = ∆ b m qb − p + y b( , ) m b(m qb − p ) + p (p − m qb − y b( , ) ) , Πb( , ) = ∆ b m qb − p + y b( , ) m b(m qb − p ) + p (p − m qb − y b( , ) ) , mb( , ) = ∆qb∆b mqb mb yb( , ) m b(m qb − p ) + p (p − m qb − y b( , ) ) , mb( , ) = ∆qb∆b mqb mb yb( , ) m b(m qb − p ) + p (p − m qb − y b( , ) ) . references [ ] g. aad et al. 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[hep-ph]]. http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . introduction a model to solve the deviation in afbb and a light higgs . -site description . mass eigenstate basis . zb interactions in the mass eigenstate basis low-energy effective theory . z-interactions in the low energy effective theory higgs potential numerical results radiative corrections to zb phenomenology at colliders conclusions a representations of so( ) b yukawa interactions and mass matrices c correlators beauty along the color line: lynching, aesthetics, and the crisis russ castronovo russ c astronovo is jean wall ben- nett professor of english and american studies at the university of wisconsin, madison. this article is drawn from his forthcoming book, beautiful democracy: aesthetics and the anarchy of global cul- ture (u of chicago p, ). in memory of nellie mckay “in aesthetic theory and criticism, the negro has not yet made any worth-while contribution,” announced the crisis of september (braithwaite ). this statement ignored the history of the crisis itself, which almost from its inception had ex- amined the status of the beautiful in relation to social justice. with columns like “music and art,” which often ran side by side with a section titled “lynching,” the crisis staged monthly confrontations between aesthetics and black print culture. the inclusion of artwork and news about black artistic achievements no doubt worked to em- bellish a journal that chronicled and fought against black victimiza- tion. the effects worked the other way, too: with each issue, aesthetics was retheorized so that beauty no longer appeared as an ideal beyond practical purpose but was instead revealed as a formal matter satu- rated by the historical content of racial atrocity. at a time when some black intellectuals found safe harbor in the doctrine of art for art’s sake, the crisis as an agent of black print culture pushed a confronta- tional aesthetics that revalued traditional categories of the beautiful. w. e. b. dubois sought to correct for deficiencies in aesthetic theory and criticism by inviting countee cullen, jessie fauset, and other prominent figures in publishing to participate in a forum about race and aesthetics. dissatisfied with the responses he received, du- bois took matters into his own hands, using the crisis to develop an uncompromising aesthetic theory. the result—his provocation entitled “criteria of negro art”—culminates in the equation of art to a political tool, famously defining art as propaganda. to observers at the time, such as claude mckay, who wrote dubois that “nowhere in your . ] [ © by t h e mode r n l a nguage a s s o ci at ion of a m e r ic a ] writings do you reveal any comprehension of esthetics and therefore you are not competent nor qualified to pass judgment upon any work of art,” the editor of the crisis had approached art using the subtlety of an ideological jack- hammer (dubois, correspondence ). to readers since, dubois’s prescription has seemed old-fashioned, constrained by a party line of culture that slighted black vernacular expres- sion in order to demand, as darwin turner puts it, a single “standard for all blacks—at least for all cultivated blacks” ( ). but when dubois declared propaganda as the criterion of african american art, he did not insist that art be created in strict ac- cord to some preexisting cultural orthodoxy. what matters instead is the instrumentality of beauty for political confrontation. this ap- proach uses aesthetics to redefine propaganda, which in both dubois’s day and ours tends to be discredited because of its overt ideological imperatives. as an endeavor “ever bounded by truth and justice,” to use the lofty description of “beauty” in the crisis, aesthetics overhauls propaganda so that it no longer connotes vul- gar partisanship but rather operates as “the one great vehicle of universal understand- ing.” aesthetics makes propaganda true by framing the concept with the history of race in ways that people, including white people, are compelled to recognize. beauty is not a matter of perception but an arena for crafting hegemony. “all art is propaganda and ever must be, despite the wailing of the purists,” dubois explains. “i do not care a damn for any art that is not used for propaganda.” and it is high time that black intellectuals develop an aesthetic theory that encourages expropri- ation: “but i do care when propaganda is con- fined to one side while the other is stripped and silent” (“criteria” ). this pronounce- ment seems muddled: how can “all art” al- ready be propaganda while “any art” has the potential to be propaganda? the answer lies in the difference between “art” and “art.” whereas “art” implies the cultural validation of unassailable tradition, “art,” a much more ductile category, does not abide prescribed judgments and instead contests the universal- ity of such judgments. dubois was led to these rather fine and orthographic distinctions from his work with the crisis that allowed him to experiment with the political uses of formalism. starting with his manifesto and reading in reverse chronological order every issue of the crisis to its first issue in , i have attempted to re-create a critical narrative that traces the development of an aesthetic theory among african american writers associated with the naacp’s national magazine. month af- ter month, the crisis assembled short notices about black achievements in painting, music, and sculpture as evidence of racial uplift. but any smooth tracing out of this narrative is in- terrupted issue after issue by the ghastly re- porting of lynchings, which make attention to beauty seem misguided at best and frivolous at worst. had not james weldon johnson already written about beauty and racial consciousness only to end with a renunciation of aesthetics? johnson’s ex–colored man seeks to ennoble black life by expressing “all the joys and sor- rows, the hopes and ambitions, of the ameri- can negro, in classic musical form” ( ). as he collects material from the deep south, the ex–colored man is poised to fuse race to aes- thetic form, implying that african american identity, like music, can be arranged—and rearranged—into universally pleasing com- positions that transcend the provinciality of racism. but a spectacle lynching derails his goal of aesthetic reclamation. frightened and ashamed, he boxes up his research and decides to pass as white, turning his back on art and rejecting his racial heritage. black life cannot be made over into the classic form of “univer- sal art” when its content is infused with the racialized specifics of murder ( ). johnson’s autobiography of an ex–colored man suggests the difficulties facing dubois and his colleagues at the crisis as they attempted beauty along the color line: lynching, aesthetics, and the crisis [ p m l a to articulate an alternative aesthetics whose principal criterion centered on propaganda. johnson’s novel also indicates the ethical diffi- culty that my essay’s association of beauty and lynching poses. dubois argues for the neces- sity of this disturbing conjunction because of his belief that aesthetics, as a broad endeavor that includes propaganda, counteracts the narrowness of spectacle violence. surveying the early history of this monthly magazine, i uncover an aesthetic theory that locates beauty at a site of crisis where violence is aestheticized even as aesthetic formalism is linked to social transformation. if “literary form itself,” as elizabeth maddock dillon writes, “can speak . . . of the creation and distribution of politi- cal power” ( ), dubois’s interest in aesthetics speaks volumes about how specific content— particularly african american personhood— often fails to meet putatively universal criteria that underwrite justice. by attending to form in an era of lynching, dubois rearticulated the initial delimitations of the beautiful, whose ab- stract parameters disallowed black lives from having merit in both the national sphere and international settings of colonization. although dubois’s “militant journal- ism,” according to david levering lewis, clearly follows in the tradition of frederick douglass’s north star, the intellectual in- heritance linking african americans to aes- thetics seems tenuous if not strained ( ). aesthetic philosophy could be downright hostile, stipu lating t hat genera l precepts about beauty always met their limit in black- ness, the negro, or africa (kant ; burke ; ruskin, political economy ). for a people that dubois’s the souls of black folk defined as the “problem” of the twentieth century ( ), the eighteenth-century neolo- gism aesthetics seemed a long way off. but by starting with the crisis and moving outward to consider black writers’ engagement of art and propaganda, including dubois’s own novelistic examples, i will bring an alterna- tive aesthetics into focus. the problem is that other issues—most notably the aestheticized violence of lynching—enter the frame as well. this friction led to dubois’s experiment with propaganda in defiance of colleagues at the crisis who did not feel comfortable with such overt politicization. as i ultimately argue, dubois reacted by pushing his agenda even more strenuously, trying to wring an activist methodology out of aesthetic formalism. aesthetics versus art in rearticulating the beautiful, staffers at the crisis walked dangerous ground, trying to re- cuperate forms of representation that had done so much injury to black people. worse still, they risked their own irrelevance, opening themselves to the accusation that effeminate dabbling in art did little to abate black vic- timization. at the forefront of the crusade for federal antilynching legislation, the crisis—as the urgency of its name suggested—had little use for racial accommodation. this stance set it apart from competing african american monthly magazines, which owed allegiance to booker t. washington and routinely at- tacked the crisis. at the helm, dubois stood for nothing less than “reshaping a race’s image of itself, and . . . serving a resounding notice to white people of a new negro in the mak- ing” (lewis ). through it all, the belief that beauty was instrumental to social justice re- mained a poignant chord in the writings of dubois and other crisis regulars including walter white and fauset. their principled stand recruited new subscribers in droves, to the alarm of the tuskegee machine: after sell- ing out the inaugural issue of , copies, dubois increased the print run to , for the december issue, and by april distribution was at , (lewis – ). each month the crisis ran “along the color line,” a section featuring notices about both black achievements and victimization, which taken together served as a record of ra- cial progress—or lack thereof—at home and . ] russ castronovo abroad. grouped under the headings “edu- cation” and “music and art,” these snippets documented the importance of intellectual and aesthetic uplift. yet categories such as “crime” and “lynching” offset these encour- aging signs in the battle against discrimina- tion. the banner for “along the color line” remained the same issue after issue: rows of corpses stretch into the distance, the horizon broken only by a corpulent white figure, an allegory of mob “justice,” who holds fast the ropes that strangle human beings (see fig. op- posite). the february crisis exemplifies the antagonistic confrontation between aes- thetics and murderous ugliness. while “mu- sic and art” applauds “the ease and freedom” of a black tenor’s performance and acclaims a “beautiful flower garden” cultivated by an- other “colored citizen,” the column “crime” records that david lee “was lynched” by “a dozen masked men” and that mar y mar- shall narrowly escaped a lynch mob after she “kill[ed] a white boy under provocation” (“music and art”; “crime”). the layout of the crisis illustrates that “music and art” is al- ways positioned against other forms of black life and against death. art does not exist for art’s sake when aesthetic categories remain adjacent to columns of crime and acts of in- justice, especially murder. art always exists for the sake of something else. to assert oth- erwise, to claim that art exists for autonomous purposes, would be to give art a freedom that the american world denies its citizens. the placement of beauty along the color line at first seems to follow the dictates of anglo-american aesthetics. william mor- ris, for instance, imbued beauty with demo- cratic potential by identif ying art as “the solace of oppressed nations” ( ). yet ideas of beauty as compensation for defeat hardly seem consistent with dubois’s activist sense of art as embattled in the everyday material- ity of racial life. a generation earlier, john ruskin, for his part, had allowed that “beauty . . . [might] be sought for in the forms which we associate with our every-day life,” but he strictly limited this search to “the drawing- room” (“lamp” ). johnson’s ex–colored man betrays how adherence to such criteria traduces racial consciousness when he likens his son, who knows nothing of his bloodline, to “a little golden-headed god, with a face and head that would have delighted the heart of an old italian master” ( ). the ex–colored man literally reproduces european classi- cism as racial amnesia. for writers who im- bibed these precepts, the task was difficult and the payoff dubious, as nathan huggins first argued: “the black artist had to convince himself that he had something to say worth saying, and that he had the skill to say it; then he had to defy the white eyes which were too often his eyes as well. all so that he could end with a work of art” ( ). traditions of anglo- american aesthetics, it would seem, fold art back on itself, so that it is never positioned among other historical categories. dubois’s innovation was to see this fold as a tear in aesthetic formalism. just as the orthographic distinction between “art” and “art” alludes to his nuanced dissent from anglo-american aesthetics, so too the juxta- position of beauty with lynching in the crisis bespeaks the impossibility of cordoning off the beautiful from racial content. formalism, in effect, is never as formal as it pretends to be; it is always a historical category. if, how- ever, beauty seems removed from historical striving, it can provoke self-doubt, leading race men and women to wonder, “after all, what have we who are slaves and blacks to do with art?” (“criteria” ). plenty, would be dubois’s response. dubois could answer so sharply because art—much of it specious and injurious—had already done so much to slaves and blacks. doing with as opposed to done to: the difference between transformative use and passive receipt of art lies in an interventionist methodology that examines aesthetic formal- ism as debatable ground on which judgments are made, criteria established as universal, beauty along the color line: lynching, aesthetics, and the crisis [ p m l a . ] russ castronovo and hegemony treated as the common sense of the majority. the sticking point in this assertion about dubois’s radical aesthetics is his finicky at- titude toward new and popular art. the cri sis under his leadership “hardly concealed its disdain for jazz, the blues, and the popular gospel song . . . [and] seldom questioned the artistic criteria of the white world” (ramp- ersad, art ). it would be pointless to ex- plain away dubois’s parochial tastes just as it would be disingenuous to pretend that his literary efforts are not “dated” and “bombas- tic” (rampersad, foreword and art ). in contrast to his pronouncement that the color line is the problem of the twentieth century, dubois’s artistic productions seem stuck in the victorianism of the nineteenth. but to ac- cept this judgment is not to surrender the ter- rain of aesthetics. only by using propaganda to cut a distinction between art and aesthetics can dubois ask, what does art do to people, and what can people do with art? construed as a political discourse about form, aesthetics theorizes what art does: the subjects it creates and limits, the analyses it forecloses and enables, and the justice it promises and the injustice it legitimates. pro- paganda, above all, represents an aesthetic concern about the form politics should take. enabling distinctions between art and aes- thetics, propaganda does not separate these two densely intertwined categories so much as turn the tables on their relation to imag- ine different criteria that give primacy to aesthetics, usually a second-order discourse, as a field of investigation devoted to under- standing art as one historical form among the many forms—legal, national, gendered—that constitute social possibilities and political horizons. instead of attempting to unlock the meaning of an artwork, aesthetics probes the initial exclusions, effects, and uses of form. while the stilted aspect of dubois’s fiction did little to trouble established standards of representation and, in fact, probably con- firmed new england ideals of refinement, his concern with aesthetic formalism strikes at assumptions about art’s role as disinterested and socially irrelevant. if his artistic tastes never shed certain niceties, dubois’s politics also never strayed too far from what adolph reed identifies as a mode of “inquiry linked to strategic action” ( ). reed identifies such inquiry as antiaes- thetic, contending that dubois’s political vi- sion was unclouded by literature or idealistic philosophy. this assessment hinges on a rigid disciplinarity that upholds politics as “an au- tonomous domain of social activity” that, as far as reed is concerned, is thankfully im- mune to literary hermeneutics, which is of- ten nothing other than an empty exercise in “formalist aestheticism” ( , ). neither formalism nor aesthetics, however, is as for- mal or as historically empty as assumed: the content of aesthetic form is a political matter that entails asking how the aesthetic field is delimited and defined in the first place. this recognition offers insight into the unequal re- lations that structure not only art but also any field (such as politics) or endeavor (such as justice) that relies on formal criteria. by dis- entangling art and aesthetics, dubois steps outside categories of the beautiful to consider art’s uses and effects. by foregrounding issues of placement— where does “music and art” belong in re- lation to “lynching”?—the crisis mapped aesthetic theory onto a geography of racial difference. the journal featured a multimedia format made possible by advances in half- tone reproduction that allowed for cheap and easy combination of lynching photographs, illustrations by black artists, and editori- als about political action (carroll ). print culture brought dubois to the radical edge of kantian critique by revealing the contin- gency of form in terms of its historically com- posite nature. the subject, according to kant, “judges not merely for himself, but for every- one” by adopting a perspective that everyone beauty along the color line: lynching, aesthetics, and the crisis [ p m l a else is presumed to already share ( ). han- nah arendt discerns deep political signifi- cance in this axiom, as aesthetic judgment rouses “the fundamental abilities of man as a political being” who “orient[s] himself in the public realm, in the common world” (between past ). but to say that individual judgment prepares the ground of collective sensibil- ity—what kant labels sensus communis (sec. )—does not put the case strongly enough. aesthetic judgment requires obligation, de- creeing a shared sensibility for all people. this strenuous discourse that tells people to agree with universal feeling is redeployed in dubois’s instruction to his people that “until the art of the black folk compells recognition they will not be rated as human” (“criteria” ). his word for this instruction, of course, was propaganda. by connecting propaganda to aesthetic judgment, dubois reactivates the the beautiful as a democratic imperative to re- vise the forms that encompass what the crisis each month identified as “the darker races.” aestheticizing violence the decades that witnessed the greatest toll of black victims at “the hands of persons un- known” also saw a flurry of academic research to codify beauty as an aesthetic science. edu- cators sought to establish psychological links between the perception of beauty and the capacity for ethical behavior. more difficult to establish is a relation between beauty and lynching. would a critic be so incautious as to stretch the limits of political good taste by associating ritualized murder with the philo- sophical discourse of aesthetics? dubois took this chance because the linkage of beauty and lynching provided an analysis of white injus- tice and a means of countering such ugliness. as university research grounded the kant- ian project in psychology, theories of univer- sal taste stumbled against “the darker races,” whose specific history seemed far removed from the vague generalities of sensus com munis. beauty and lynch law exist at different ends of the color line, each appealing to justice either as imminent in a formal world where individual difference does not signify before more global concerns about proportion, sym- metry, and purity or as long deferred in a world so out of proportion that human beings are burned alive. at the same time, aestheti- cized representations of racial subjects cannot be held apart from the history of lynching. “rituals of aggression and negation” remain even today the inevitable context of “beautiful black male bodies,” according to kobena mer- cer ( – ). these comments, made on look- ing at robert mapplethorpe’s photographs, stem from a history in which the two ends of the color line—lynching and beauty—meet up in spectacles of violence. lynching and beauty can be examined together only through a politicized methodology—might we use the term propaganda?—that takes aim at national criteria that evaluate white violence as though it were a work of art. activists working for the naacp experi- mented with this sort of methodology, debat- ing the extent to which beauty could facilitate visions of a just world. the risks of the experi- ment were by no means incidental: in the face of mounting statistics that “on the average a black man, woman, or child was murdered nearly once a week, every week, between and by a hate-driven white mob,” an aes- thetic strategy seemed not only implausible but dangerous by legitimating a turn away from ugly social realities terrorizing black populations (tolnay and beck ix). even worse, such a solution could aestheticize the violence that was the mainstay of that terror. dubois’s undertaking at the crisis required vigilance lest “music and art” beautify violence, mak- ing murder seem a thing of common sense. writing in the context of a different terror, walter benjamin in his famous artwork essay would pinpoint this danger as an aesthetici- zation that makes destruction beautiful. in an artwork essay of his own, dubois seeks . ] russ castronovo criteria that will differentiate between an out- look that aestheticizes racism and one that uses “beauty to set the world right” (“crite- ria” ), a distinction that benjamin would later reproduce as the difference between the aestheticization of politics and the politiciza- tion of aesthetics. benjamin attempted to hold the line between the two by, on the one hand, valorizing the role of communism in “po- liticizing art” and, on the other, denouncing aesthetic politics as the watchword of fascism ( ). dubois faced a very different task, if only because the repressive aspects of ameri- can culture remained fused to a liberal ideol- ogy of rights, not to rigid state control. unable to draw neat distinctions, he conf lated aes- thetics and politics by imagining the possibil- ity of doing something political with art. the payoff was small and the risks enormous since the media in the united states had no qualms about doing something aesthetic with poli- tics by presenting african american dehu- manization as a source of white pleasure. the market never can stock enough “uncle toms, topsies, good ‘darkies’ and clowns” (“crite- ria” ). too plainly, the campaign of extra- legal terror against black people, promoted by literature such as thomas dixon’s romances of the klan, justified in film by d. w. griffith, and accepted by the mainstream press, was in accord with national taste. dubois felt sufficiently dogged by these pitfalls to begin his artwork essay by ventril- oquizing the concerns of those who doubted the usefulness of drawing methodological links between efforts to create beauty and protests demanding respect for blacks as citi- zens and human beings. he wondered: how is it that an organization like this [the naacp], a group of radicals trying to bring new things into the world, a fighting organi- zation which has come up out of the blood and dust of battle, struggling for the right of black men to be ordinary human beings—how is it that an organization of this kind can turn aside to talk about art? (“criteria” ) no great leap was needed to imagine this anti- aesthetic position because dubois and his comrades at the crisis had long asked such questions of themselves. in its more sanguine moments, the crisis would make the case that a turn to aesthetics as a discourse “about art” was never an evasion but rather a mode of confrontation. but optimism was often dif- ficult to come by, and dubois, white, and fauset frequently asked when beauty had ever stopped a lynching. did not the aesthetic as- pects of lynching itself—its cruel drama, ritual orchestration, and spectacle—invalidate polit- ical aesthetics even before it got under way? the aest hetic dimension of ly nching comes through in the work of historians who describe the systematic persecution of blacks as “theater,” “festival,” and stage show (dray xii, ; tolnay and beck). in a haunting collec- tion of picture postcards of lynchings, james allen confronts the grisly aesthetic of torture. likening the photographic record of strung- up bodies to images in the tradition of nature morte, which typically displayed fruit or game for viewers’ pleasure, allen implies how vi- sual art played an important role in commer- cializing atrocity. connecting the troubling aesthetics of violence to classical representa- tion, michael hatt reads a photograph of one lynching victim as a “grotesque parody of par- migianino’s vision of st. jerome,” the twisted, murdered body an eerie citation of the saint’s posture ( ). the spectacular nature of racial persecution established lynching as public art, what philip dray calls a “‘folk pornography’ that made for welcome, titillating reading” in the morning newspaper ( ). macabre orches- trations of mob injustice render murder fit for public consumption. in his disquieting book at the hands of persons unknown: the lynch ing of black america, dray refuses to shrink from these aesthetic aspects when discussing the spectacle lynching of henry smith before ten thousand people in . as smith was be- ing returned to the scene of his alleged crime, the train stopped in texarkana, and the crowd beauty along the color line: lynching, aesthetics, and the crisis [ p m l a urged that the lynching take place then and there. if not for the intervention of paris’s lead- ing citizens, including the district attorney, to ensure smith’s safe passage to his murder, the community would have forfeited its “right to stage and enjoy its own lynching” ( ). newspapers t hat publicized t he time when a lynching would take place, special trains scheduled to shuttle white folk from the countryside to the event, and the crowds that gathered made racial horror a grotesque distortion of sensus communis. as an aes- thetic object, the victimized black body be- comes the focal point of white subjectivity. lynching’s performative nature produces a drama of white community that, as hatt argues, erases potential class antagonisms among whites. in short, the collective nature of aesthetic judgment that arendt defines as crucial to the shared endeavor of political life becomes the terrible standard of white community (lectures). the kantian subject who feels that he or she ought to agree with presupposed tastes (sec. ) reappears in monstrous guise at lynchings, where many spectators repor ted ly felt unable to turn away. “i was fixed to the spot where i stood, powerless to take my eyes from what i did not want to see,” confesses the ex–colored man of his behavior at a georgia lynching. “it was over before i realized that time had elapsed” (johnson ). the ex–colored man only ex- tricates himself afterward, the retrospection of his telling separating him from the crowd. arendt’s account of spectatorship describes his situation: “spectators exist only in the plu- ral. the spectator is not involved in the act, but he is always involved with fellow specta- tors. . . . [t]he faculty they have in common is the faculty of judgment” (lectures ). the ex–colored man’s experience puts a horrific twist on arendt’s portrait of public viewing: judgment is exactly what the lynchers have in common, their decision that a black person must die a public death providing confirma- tion of their social cohesion as white people. difficult as it is to say, lynching was an aesthetic performance. this point is driven home by new york times coverage of the lynching of will porter in a kentucky op- era house in . after he shot and killed a white man, porter was hauled off to the city jail. suspecting that a mob would overrun the jail, the city marshal hid his prisoner be- neath an opera-house stage. the mob tracked porter there and quickly hit on the idea of ex- ecuting him on stage. turning on the house lights and setting their captive before props and scenery, the mob “silhouetted against the theatre walls” fired two hundred bullets into porter’s body. the times made the most of the event’s aesthetic possibilities, describing the lynching as a “melodrama” that was “staged” in front of an “audience of half a hundred de- termined avengers.” when the performance was over, “the lights were extinguished, the curtain lowered, and the mob then filed out” (“lynched”). dramatic sensibilities lend order to the scene, giving this revenge play closure and organizing the mob into an audience. by the next day’s edition, the times’s sarcasm had soured the aesthetics of lynching: “what- ever else may be said about the inhabitants of livermore, ky., it cannot be denied that in them the dramatic sense is strongly devel- oped. for, when they deemed it expedient to lynch a negro, they managed to do the famil- iar deed in a way not only entirely new, but highly picturesque” (“topics”). aestheticiza- tion revealed that beauty and art could not be trusted in the campaign against white injus- tice. too easily, the “picturesque” nature of violence overshadowed the reality of porter’s death, so that murder became melodrama. the sheer fact that the times could de- scribe lynching, no matter how mockingly, as theatrical spectacle suggests the urgency of a politicized aesthetics. where dubois supplied “criteria of negro art,” walter white’s exposé of lynching offers a scathing corollary that might be entitled “criteria of white south- ern art.” although white never organized . ] russ castronovo his findings into a bold treatise on the scale of dubois’s artwork essay, he explained the mutilation and murder of blacks as fulfill- ing aesthetic criteria common to rural back- waters of the south. as assistant secretary of the naacp, white used his light skin to pose as a white newspaper reporter covering a campaign of terror against black share- croppers in arkansas that left, by naacp estimates, at least two hundred dead. his investigations led to rope and faggot, a psychosocial study that diagnosed the public shooting, hanging, and burning of black peo- ple as an instinctive aesthetic response among poor southern whites. just as researchers in united states universities theorized the ap- peal of the beautiful as psychological instinct, white drew on cultural psychology to explain why lynching seizes white imaginations. for the white subject of the unindustrialized south, lynching provides pleasure by inter- rupting the uneventfulness of small-town life. literature underwrites white’s study of white interiority: the “leaden colours” that sinclair lewis used to depict midwest life seem a chro- matic explosion when set against the “end- less routine of drab working-hours and more drab home life” of the “average small town in the south.” in the absence of “the merry-go- round, the theatre, the symphony orchestra,” lynching satisfies an instinctual “human love for excitement” ( ). lynching fills the void of aesthetic pleasure and, in the process, be- comes less a surrogate for amusement than an aesthetic activity in its own right. years later, dubois supported the idea of white art as injurious to black people by at- tributing “the increase in lynching in ” to birth of a nation (dusk ). the peak soon leveled off, according to white. but while rope and faggot contends that lynchings de- clined somewhat in the s, the savagery of the mob intensified. “[h]uman love for ex- citement” made lynching still more ghastly: “against this gratifying decrease in number of victims is the greatly aggravated brutality, often extending to almost unbelievable tor- ture of the victim, which has marked lynch- ings within recent years” ( ). as the bonfires rose higher and the mutilation of the lynched corpse entailed ritualistic dismemberment, shock and outrage were harder to come by. aesthetic disinterest—the sign of mature reflection and appreciation—literally makes for a lethal performance. excitement cre- ated an imagined public that, paradoxically, proved indifferent to lynching. as white charged, “[a]n uncomfortably large percent- age of american citizens can read in their newspapers of the slow roasting alive of a hu- man being in mississippi and turn, promptly and with little thought, to the comic strip or sporting page. thus has lynching become an almost integral part of our national folkways” (vii). aesthetic disinterest manages southern horrors so that the local practice of terror seems abstractly american. this sense of “national folkways” is a false universal that relies on a parochial under- standing, which limits aesthetics to the the- atricality of ritualized violence. for dubois, politically useful aesthetics depends not on false universals but on the avowed partiality of propaganda. rather than neutralize mur- derous regionalism with an abstract aesthet- ics that pretended to be beyond location, the crisis set “music and art” against reports of lynching under the banner of a section en- titled “along the color line.” beauty has a location, and it’s not pretty. organized propaganda the geography of beauty in the crisis invites dissonance, assembling evidence of black achievements in painting and performance while confronting readers w it h accounts of injustice that kept at the forefront the naacp’s emphasis on political action. aes- thetic theory envisioned by the crisis insisted on something still more: not only may beauty counteract the mounting record of abuse but beauty along the color line: lynching, aesthetics, and the crisis [ p m l a also, as a kantian endeavor twisted by the materiality of racial violence in america, the political dimension of aesthetic judgment would establish african americans’ sense of right as the common sense of the nation. the development of aesthetic theory at the crisis in reviews, manifestos, and liter- ary contests lacked the rigor of an academic inquiry into beauty. with faculty members such as george santayana and john dewey, harvard college could claim to be a major contributor to american aesthetics for three decades. it is by no means incidental that santayana served as dubois’s tutor and that dewey’s pragmatism influenced dubois. de- spite these lines of affiliation, it is difficult to say whether the seeds of dubois’s interest in aesthetics were planted in his student days at harvard, to sprout later in the pages of the crisis, or whether harvard was catching up with the preeminent african american pub- lication of the day. certain it is, however, that dewey invested aesthetics with the transfor- mative capacity to emancipate people from stultifying convention. his art as experience expresses this sentiment: art exerts a “liberat- ing and uniting power” that is “looked upon with the eye of suspicion by the guardians of custom. . . . art is a mode of prediction not found in charts and statistics, and it insinu- ates possibilities of human relations not to be found in rule and precept, admonition and administration” ( ). dewey’s meditation goes global at this juncture, as he hypoth- esizes a “common world” that would be not national but cosmopolitan, a community ex- panding beyond citizens of the united states to include geographically unspecific “human relations.” his impression of aesthetic experi- ence echoes the discourse of pan-africanism that had been appearing regularly in the pages of the crisis. did harvard educate dubois, or was the crisis making an impression among leading united states intellectuals? “when we enter into the spirit of negro or polynesian art,” dewey writes, we experience a refresh- ing dislocation that frees us from the bias of a first world perspective. stilted tastes, stuffy preconceptions, and cloying criteria prized by western subjects “melt away” in the encoun- ter. global culture widens access to aesthetic sensibilities, although it remains a question if that experience is available only to first world tourists who consume objets d ’art taken from oceania or africa. as he rejects rationalism in favor of “melting,” dewey slips into primitivism, accepting the belief that life forces enervated by mechanization and stan- dardization are revitalized by contact with “tribal” influences ( ). such exoticism im- plies that dewey’s transformative aesthetics may not be all that transformative. world art had been a touchy matter since the advent of world war. when the director of princeton’s psychology laboratory, herbert langfeld, went to cambridge to deliver a series of lectures at harvard, he began by invoking “the aesthetic attitude” as reason enough to ex- plain the united states’ involvement in world war i. why would a “free nation” allow itself to become entangled in what many viewed as a conflict among european powers battling over the last shreds of feudal privilege? “the sense of beauty,” langfeld declared, drew the united states into the war on behalf of cultural trea- sures threatened by military aggression ( ). art appreciation justifies military force: it requ i red no organiz ed propaganda to arouse the indignation of neutrals when an- cient churches, libraries, and town halls were leveled by the invaders. the indignation was immediate and almost universal, as is the case in the arousal of a primitive instinct, and it was not because these were useful buildings, or because they were devoted to worship, but evidently and undeniably for the reason that they were works of art. ( – ) beauty awakens citizens to injustice, working at an instinctual level to fuse ethical concern and artistic appreciation. “organized pro- paganda” is superfluous because the inborn . ] russ castronovo psychological response to the beautiful justi- fies united states intervention in making the world safe for democracy. state-sponsored propaganda is unnecessary because aesthetic judgment is already hardwired with the cri- teria of the state; universal feelings of sensus communis have a decidedly american cast. the campaign against lynching, in con- trast, required organized propaganda. ac- tivists at the crisis were not willing to wait for a solution that would bubble forth from aesthetic instincts. left to its own devices, the “art” of lynching, as white argued, had been hard at work in the south victimizing black populations while entertaining whites. even so, academic theorists resisted imperatives to organize art as propaganda. langfeld’s the aesthetic attitude ( ) draws the line at using art to rally supporters around a cause: “aesthetics can merely indicate that as soon as a work of art communicates nothing but a lesson to the observer, it ceases to be for him a work of art” ( ). lest aesthetics fo- ment agitation in place of harmony, langfeld locates repose at the heart of beauty. when “one views an object aesthetically,” symmetry, proportion, and balance provide an intrinsic code for the self. aesthetic power overwhelms the individual who encounters these precepts, internalizing them as the beautiful alignment of subjectivity to form. no battle takes place since the individual’s participation in bend- ing self to form occurs “without any opposi- tion upon one’s part” ( ). langfeld embraces this paradox, stipulating that the self should be active in cultivating aesthetic repose. for the theorist who sees “no organized propa- ganda” as freedom’s negative condition, aes- thetic repose delays political engagement. aesthetic theory in universities was a bun- dle of contradictions that, on the one hand, en- couraged aesthetic repose as a precondition for deliberate action and, on the other, discour- aged politicized uses of art as doctrinaire and less than beautiful. the authority of his alma mater notwithstanding, dubois was moved to challenge this wisdom and ask, “what has this beauty to do with the world?” writing at the height of the harlem renaissance, he charged that aesthetic repose not only provided a ra- tionale for white disinterestedness but also encouraged indifference among a younger generation of black artists. he proposed in- stead an aesthetic strategy that took the idea of beauty’s connection to the world as a geo- political provocation toward global thinking, using aesthetics to open a wedge between na- tionalism and internationalism. aesthetics survived in the crisis largely as a global discourse that lent diasporic en- ergy to its pages. in a series of letters mailed to the crisis from the soviet union, claude mckay credited marcus garvey, no doubt to dubois’s chagrin, with recognizing the significance of “organized propaganda” for countering decades of “white american pro- pagandists.” in contrast to langfeld, who saw no need for organized propaganda and assumed that art would do its political work instinctively, mckay takes propagandistic art as direct action to stem a flood of “mis- information” that begins with uncle tom’s cabin. organized propaganda, he argues, can be useful precisely for organizing blacks to advance “racial interests . . . on a world scale, to combat their white exploiters and traducers” ( – ). dubois had long oper- ated on “a world scale,” and his attraction to propaganda rescued him from the instinctual beauty of nationalism backed by langfeld and other defenders of western civilization. in a january article on neocolonialism and pan-africanism, dubois stated, “nothing is more interesting than to read the carefully prepared propaganda upon which the brit- ish empire thrives” (“black man” ). as he examines alibis for imperialism, dubois responds with a mixture of icy condescen- sion and fascination, viewing propaganda’s sleight of hand as “interesting” because what had come to interest him was the power of representation—and misrepresentation—to beauty along the color line: lynching, aesthetics, and the crisis [ p m l a achieve hegemony. at this point, however, his aesthetic theory conceptualizes propaganda not as a tactic of transformation but only as a force aligned with domination. hence the difficulty of articulating politicized aesthet- ics. the presence of staffers at the crisis intent on salvaging art from what was perceived as blatant overpoliticization did not make things any easier. thus, if began with dubois’s warming up to political aesthetics, the line against propaganda was fixed as ever by feb- ruary, when the crisis condemned dixon’s the leopard spots for “viciously” trespassing the “color line type of fiction” for “purposes of propaganda” (braithwaite ). conf lict came with the territor y: the staff of the naacp encouraged propaganda, deplored the intrusion of politics into litera- ture, and called for more activist writing, dis- agreeing with one another each issue. arnold rampersad takes stock of this uncertainty, noting that dubois “had written so ambiva- lently and confusedly about the relation of art to propaganda that misinterpretation on this subject was inevitable” (art – ). never- theless, dubois’s appreciation of propaganda steadily grew in proportion to his impatience with nationalist criteria of art. as dubois makes global connections between imperi- alist struggles among european powers over africa and the exploitation of western work- ing people, he condemns propaganda as a t hreat to democrac y. his condemnation, however, is laced with awe as he recognizes that propaganda is a “tremendous weapon in our day” (“black man” ). this mixed as- sessment raised the possibility of revaluing propaganda so that prejudice against art with overt agendas might be temporarily set aside and beauty construed as a politically prag- matic form. not for nothing would he look back on this stage of his career and remem- ber it as a time of training for his “role as a master of propaganda” (dusk ). despite dubois’s reevaluation of political aesthetics, white persisted in viewing propa- ganda as a shameless tool of the master class. “negroes anxious to return south” and “magnolia state invites wandering ne- groes home,” ran headlines in southern pa- pers trying to halt the exodus of black labor to northern cities. white cited these jour- nalistic “untruths” as proof of the “mythi- cal and slanderous propaganda” designed to keep blacks literally in their place (“success” , ). given his uncompromising view of propaganda, white no doubt bristled at du- bois’s review of his first novel, the fire in the flint. reportedly written in just twelve days, the novel concerns a harvard-trained black physician who returns to practice his profes- sion in a georgia town where working-class whites practice intimidation and lynching with a professionalism all their own. dubois praised the novel generally but found fault with white for having imbibed the cant of the former planter class to the extent that the fire in the flint lets southern gentility off the hook by casting white poverty and ignorance as the sources of black victimization. having no use for class nostalgia, dubois criticized this aspect of the fire in the flint as “based on the propaganda which sons and daughters of slave-barons have spread” (“fall books”). viewing propaganda as merely nega- tive, white undercut art’s use for democratic struggle. in the fire in the flint and flight, his novel two years later, he invalidated aes- thetics by gendering aesthetic interest as a feminine preoccupation. in a world where black masculinity is under attack, beauty is hardly the weapon of choice, for it represents a debilitating detour from hands-on politics. art jeopardizes black masculinity by invit- ing suspicions that the doctor in the fire in the flint, an avid reader, is not only “deca- dent” and “effete” but also “a little queer in the head,” disposed to “moral turpitude and perversion” ( ). the charge of queerness at once hypersexualizes and emasculates black men, raising the troubling implication that art in the context of lynching is somehow . ] russ castronovo responsible for violence. like lynching, art incites panic over black male sexual devi- ance and then punishes black men for that construction. white exposes the addictive unreality of this sexual-gender mythology by speaking of beauty in both novels as an “opi- ate” (fire ; flight ). the best the doctor can do is use literature as a narcotic to stu- pefy political consciousness when life under jim crow becomes unbearable. mimi, the heroine of flight, turns a more sympathetic ear to art, taking it in as “an opiate to forget hard circumstance.” instead of finding a use for art, she simply uses it, becoming strung out on opera taken in from the cheap seats at carnegie hall, the sopranos and tenors affect- ing her “as drugs or liquor to addicts—they swept her up, up above her narrow, difficult existence to a world where cares and sorrows and toils did not exist” ( ). flight pushes a “just say no” attitude toward aesthetics, fear- ful that all beauty leads to illusions of escape and false transcendence. white’s novels spoke for many writing about art and literature in the crisis, who, because they did not believe in propaganda, saw little value in aesthetics. this rejection remains consistent with the deprecatory gendering of aesthetics. fauset, usually a staunch ally of dubois, elaborated on the social inefficacy of beauty as femi- nine weakness in her novella of passing, “the sleeper wakes.” appearing serially in the cri sis, fauset’s narrative asks just how much so- cial power beauty can exert. not much is her answer. only through the deracialization of beauty does her heroine, amy, achieve social status; by passing as white, she finds a hus- band who showers her with jewelry. though cozy with white economic power, amy recog- nizes her powerlessness to curb her husband’s virulent racism; she ultimately judges her beauty as weak—indeed, as effeminate. she correctly judges her personal attractiveness to be a valuable sexual commodity in the eyes of white men, but she errs in investing it with any political valence. when she tries to cash in on that asset to purchase social justice, she only receives proof of beauty’s lack of value. stepping between her husband and a black servant, who are about to come to blows, she desperately clings to the white man to pre- vent him from fulfilling his threat to have the black man “hanging so high by midnight” ( ). for a decade, the crisis had been coun- teracting the ugliness of black victimization with occasional remarks on african ameri- can artistic accomplishments. now in fauset’s novella of , beauty goes head to head with lynching—and comes up short in the contest. bent on ly nching, her husband pries apart her arms, leaving amy clutching at self-accusation: “how, how could she keep him back! she hated her arms with their fu- tile beauty” ( ). stigmatized as feminine, beauty has no role to play in the defense of black masculinity. overvaluing beauty, spe- cifically her own physical attractiveness, fau- set’s heroine blunders in thinking that a white husband would prize physical attractiveness over deeply held racism. once beauty is asked to justify something other than its own exis- tence, once a race woman tries to put it to use in the belief that art may be for something other than its own sake, it fades. in publish- ing fauset’s novella, the crisis undid its own attempts to distill a political methodology from aesthetics. this contradiction moved dubois to action in subsequent issues. an alternative aesthetics announcing the criteria for the naacp’s literary prizes of , the crisis offered this advice to aspiring writers: we want especially to stress the fact that while we believe in negro art we do not be- lieve in any art simply for art’s sake. we want the earth beautiful but we are primarily in- terested in the earth. we want negro writers to produce beautiful things but we stress the things rather than the beauty. . . . use propa- ganda if you want. (“krigwa”) beauty along the color line: lynching, aesthetics, and the crisis [ p m l a a lt hough t hese guidelines came wit h no list of examples, dubois’s quest of the sil ver fleece and dark princess would have fit the bill. while it is easy to see these novels as overtly, even blatantly, political, a lot of work—perhaps too much—must be done to claim these novels as artistic by conventional academic standards. dubois had few qualms about downplaying the artistic value of quest and years later favorably evaluated the novel not as a literary artifact but as “an economic study of some merit” (dusk ). it may be wasted effort to claim these novels as artistic, but locating them as aesthetic interventions is another story. aest het ics sat u rates t hese i na r t ist ic novels. in the first crisis of dark princess, matthew feels at a loss when a reference to benedetto croce’s aesthetic f lies over his head. wit h per fect aplomb he recol lects himself and belts out a negro spiritual to convince a congress of the world’s “darker races” that african americans are ready to take part in worldwide revolution. his aes- thetic range—diving into the depths of afri- can american culture to resurface with the “great song of emancipation”—makes an eloquent case for the political capacity of his brethren ( ). he demonstrates that capac- ity himself by running for the united states congress. soon disgusted by the ugliness of electoral politics, he turns instead to art, hanging prints by picasso, gaugin, and ma- tisse on his walls. testing the limits of aes- thetic representation, he questions standard forms of political representation that entail graft and compromise. art provides solace for the “esthetic disquiet” matthew feels at bar- tering away principle in the “political game” of electioneering ( ). but in no way does art displace politics. abandoning the usual cri- teria of “ideal beauty, fitness and curve and line,” he develops an interest in the iconoclas- tic beauty of picasso—“a wild, unintelligible thing of gray and yellow and black ” ( ). this avant-garde sensibility refuses the regu- larities of the color line: his expanded palette highlights the global canvas of asian and af- rican decolonization movements. matthew’s work as a ditchdigger actu- alizes dubois’s advice to aspiring writers that art should be “primarily interested in the earth.” art, like matthew’s days in the trenches, is untranscendent, never escaping the conditions of its production. the politi- cian turned day laborer knows exactly how much he has paid for the picasso painting, a price he measures in the toll that back- breaking labor takes on his body. looking at the artwork on his walls, matthew has a revolutionary insight: “i was a more com- plete man—a real unit of democracy!” ( ). his appreciation of iconoclastic visual forms raises questions about how identity is defined in the first place. no process is more political than this initial delimitation; too often po- litical lines are drawn that bypass the basic “units” of democracy. an alternative aes- thetics is not about beauty; that topic is the property of a conventional discourse on art. instead, radical aesthetic judgment concerns the forms that politics takes—as personal unit, nation-state, or more cosmopolitan en- tity. matthew’s focus on his individuality is actually a global recognition that all other people also exist as units of democracy. his avant-garde tastes encourage an identity that expands beyond boundaries of state citizen- ship. this universal thinking sharpens his interest in the world revolutionary organi- zation that appears from time to time at the novel’s outer edges. with this worldwide alli- ance, dubois imagines a politics of universal form, dramatizing wai chee dimock’s claim that aesthetics severely questions the tax- onomy of the nation-state. critique in dark princess is formal: by thinking about units, dubois exposes the united states state as an idiosyncratic form that fails to be common to all. discerning an alternative aesthetics is harder in quest because beauty is bought and . ] russ castronovo sold relentlessly in the novel. beauty in this case is cotton grown in an alabama swamp, appropriated by local white gentry, and con- verted into commodities by venture capital- ists. tracing cotton from its cultivation to its manufacture as textile, quest models an aesthetic judgment that refuses to transcend the circumstances of beauty’s production. the cotton that bles and zora grow in the swamp is “the beautifullest bit of all” because it re- calls the “brown back of the world”—both the earth and african american laborers—from which it sprang ( ). since the discourse on beauty, which brings black students into con- tact with white schoolmarms, is so full-blown in quest, lynching is never distant. as a topic of conversation that momentarily unites black men and white women, beauty also provokes white paranoia and threats of violence. when bles regales a white teacher, mary taylor, with vivid description of a cotton field in bloom, his words convert the landscape she had seen as “desperate prose” into “poetry” that begins to work on her soul—and her body ( ). bles’s talk about the color and form of the silver fleece produces aesthetic repose in the rapt listener: “‘ah! that must be beautiful,’ sighed miss taylor, wistfully, sinking to the ground and clasping her hands about her knees” ( ). mary behaves as academic research on aes- thetic science dictates that a subject should, rendering herself passive before bles’s beauty. but in the racialized contexts of alabama, aesthetic repose is loaded with the myth of the white woman’s vulnerability to black male physicality. as bles becomes aware that two white men are witness to his discourse on beauty, a discourse that mary sexualizes by going down on her knees before a black man, he recognizes the peril of his situation. beauty in the cotton field encourages mary to forget these contextual factors, and she realizes with a start that “the fact of the boy’s color had quite escaped her” ( ). bles does not enjoy that luxury. his discourse on beauty never outstrips violence and death in the south; to forget the location of aesthetic experience is to risk one’s life. notes . on the crisis and washington, see carroll . . exact numbers are hard to come by: “estimates made by the naacp and by anti-lynching activists . . . suggest that the number of black victims ranged from , to , ” (gunning ). . the allusion to nature morte accompanies allen’s photographic montage (allen and littlefield). . on the lynchings in phillips county, arkan- sas, see dray – . works cited allen, james k. without sanctuary: lynching photogra phy in america. santa fe: twin palms, . allen, james, and john littlefield, comps. without sanctu ary: photographs and postcards of lynching in america. – . may . arendt, hannah. between past and future: eight exer cises in political thought. new york: viking, . ———. lectures on kant’s political philosophy. chicago: u of chicago p, . benjamin, walter. “the work of art in the age of me- chanical reproduction.” illuminations: essays and reflections. new york: schocken, . – . braithwaite, william stanley. “the negro in literature.” crisis: a record of the darker races sept. : – . burke, edmund. a philosophical enquiry into the origin of our ideas of the sublime and the beautiful. london: routledge, . carroll, anne. “protest and affirmation: composite texts in the crisis.” american literature ( ): – . “crime.” crisis: a record of the darker races feb. : . dewey, john. art as experience. new york: capricorn, . dillon, elizabeth maddock. “fear of formalism: kant, twain, and cultural studies in american literature.” diacritics . ( ): – . dimock, wai chee. “aesthetics at the limit of the na- tion: kant, pound, and the saturday review.” ameri can literature ( ): – . dray, phillip. at the hands of persons unknown: the lynching of black america. new york: random, . dubois, w. e . b. “the black man and the wounded world: a history of the negro race in the world war beauty along the color line: lynching, aesthetics, and the crisis [ p m l a and after.” crisis: a record of the darker races jan. : – . ———. the correspondence of w. e. b. du bois. vol. . ed. herbert aptheker. amherst: u of massachusetts p, . ———. “criteria of negro art.” the norton anthology of af rican american literature. ed. henry louis gates, jr., and nellie y. mckay. new york: norton, . – . ———. dark princess: a romance. millwood: kraus, . ———. dusk of dawn. millwood: kraus, . ———. “fall books.” crisis: a record of the darker races nov. : . ———. the quest of the silver fleece. boston: northeast- ern up, . ———. the souls of black folk. boston: bedford, . fauset, jessie. “the sleeper wakes: a novelette in three installments.” crisis: a record of the darker races aug. : – ; sept. : – ; oct. : – . gunning, sandra. race, rape, and lynching: the red record of american literature, – . new york: oxford up, . hatt, michael. “race, ritual, and responsibility: perfor- mativity and the southern lynching.” performing the body / performing the text. ed. amelia jones and an- drew stephenson. london: routledge, . – . huggins, nathan irvin. harlem renaissance. new york: oxford up, . johnson, james weldon. the autobiography of an ex– colored man. three negro classics. by booker t. washing ton, w. e . b. dubois, and johnson. new york: avon, . – . kant, immanuel. the critique of judgment. trans. james creed meredith. oxford: clarendon, . “krigwa, .” crisis: a record of the darker races jan. : . langfeld, herbert sidney. the aesthetic attitude. new york: harcourt, . lewis, david levering. w. e. b. du bois: biography of a race, – . new york: henry holt, . “lynched on stage; shots came from pit.” new york times apr. : . mckay, claude. “soviet russia and the negro.” crisis: a record of the darker races dec. : – . mercer, kobena. “looking for trouble.” transition ( ): – . morris, william. hopes and fears for art. boston: rob- erts, . “music and art.” crisis: a record of the darker races feb. : – . rampersad, arnold. the art and imagination of w. e. b. du bois. cambridge: harvard up, . ———. foreword. the quest of the silver fleece. by w. e. b. dubois. boston: northeastern up, . – . reed, adolph l., jr. w. e. b. du bois and american politi cal thought: fabianism and the color line. new york: oxford up, . ruskin, john. “the lamp of beauty.” the seven lamps of architecture. . london: dent, . – . ———. the political economy of art: being the substance (with additions) of two lectures delivered at manches ter, july th and th, . london: smith, . tolnay, stewart e., and e. m. beck. a festival of violence: an analysis of southern lynchings, – . ur- bana: u of illinois p, . “topics of the times: a lynching of a new sort.” new york times apr. : . turner, darwin t. “w. e. b. du bois and the theory of a black aesthetic.” the harlem renaissance reexamined: a revised and expanded edition. ed. victor a. kramer and robert a. russ. troy: whitson, . – . white, walter. the fire in the flint. new york: negro up, . ———. flight. new york: negro up, . ———. rope and faggot: a biography of judge lynch. new york: arno, . ———. “the success of negro migration.” crisis: a record of the darker races jan. : – . . ] russ castronovo http://www.hts.org.za open access hts teologiese studies/theological studies issn: (online) - , (print) - page of original research read online: scan this qr code with your smart phone or mobile device to read online. author: volker kessler , affiliations: department of philosophy, practical and systematic theology, college of human sciences, university of south africa, pretoria, south africa akademie für christliche führungskräfte, gummersbach, germany corresponding author: volker kessler, volker.kessler@me.com dates: received: nov. accepted: mar. published: july how to cite this article: kessler, v., , ‘the beauty of spiritual leadership: a theological-aesthetical approach to leadership’, hts teologiese studies/ theological studies ( ), a . https://doi.org/ . /hts.v i . copyright: © . the authors. licensee: aosis. this work is licensed under the creative commons attribution license. introduction ‘what is beautiful about leadership?’ this question entered my mind whilst i was reading timothy : in my german bible, which describes church leadership as a ‘beautiful task’ (‘schöne aufgabe’). the english standard version reads, ‘if anyone aspires to the office of overseer, he desires a noble task’. the greek word is kalos, which can be translated as ‘good’ or as ‘beautiful’. most english bible translations explain it as ‘a good task’ or ‘a noble task’. there are (at least) four german bible translations using the word ‘schön’ and two french bible translations using the word ‘belle’. two german bible commentaries opt for the translation ‘schön’ and discuss the beauty of the leadership task (grünzweig : – ; roloff : , ). timothy : is the starting point of a longer section about appointing the right persons as ‘overseers’, referring to the leadership in a local parish (roloff : ). the task of church leadership is important and carries considerable responsibility; therefore an overseer needs several qualifications (verses – , similar to the list of virtues in tt : – ). it can also be a hard task, challenged by god’s opponents ( tm : b, tt : b). but first of all, this task is beautiful (kalon), and thus it is, according to greek logic, worthy to be desired ( tm : ). in new testament times, the office of an elder was regarded as noble. however, that is rarely the case in germany, where both the mainline churches and the majority of the free churches have difficulty finding volunteers for church leadership. often, when a church member is approached, he or she will answer, ‘i’m not that stupid. i won’t do that to myself’. obviously, these people do not see much beauty in a church leadership position: it does not bring either money or honour but rather a lot of criticism once a person is in office. it may be that in other cultures and in certain denominations, like pentecostal churches, the office of an overseer has more prestige than it generally has in the german context. .züricher bibel, elberfelder Übersetzung, hoffnung für alle and gute nachricht (bibleserver ). .la bible du sermeur and segond (biblegateway ). the aim of this article is to investigate two links between beauty and leadership: what is beautiful about spiritual leadership? why should spiritual leaders bother about beauty? this study was motivated by the bible verse timothy : and the observation that, at least in the german context, church leadership is no longer seen as a beautiful task. after a preliminary note on theological aesthetics, the paper discusses several approaches towards the link between aesthetics and transformation of the world, among them god becoming beautiful by rudolf bohren and christianity, art and transformation by john de gruchy. the article finally argues that: ( ) spiritual leaders are beautifying the church and beyond and ( ) spiritual leaders should strive for beauty as diligently as they strive for truth and goodness. statement ( ) is drawn from the propositions that (a) the spirit is the real leader of the church, (b) church leaders are partaking in the work of the spirit and (c) the spirit is beautifying the church and beyond. this is a theological statement, not a phenomenological one. a small poll provides some answers to the questions: ‘what is beautiful about leading?’ and ‘what is not beautiful about leading?’ an example of a german kindergarten illustrates some benefits of an aesthetical approach. contribution: this article focuses on the neglected area of aesthetics in the context of leadership. it aims to encourage christian leaders to fight against the ugliness of the world and make the world more beautiful. keywords: aesthetics; spiritual leadership; church leadership; holy spirit; beautifying; transformation; practical theology; rudolf bohren; john de gruchy; patrick sherry. the beauty of spiritual leadership: a theological- aesthetical approach to leadership read online: scan this qr code with your smart phone or mobile device to read online. note: special collection entitled christian leadership, sub-edited by wessel bentley (unisa). http://www.hts.org.za� http://orcid.org/ - - - mailto:volker.kessler@me.com https://doi.org/ . /hts.v i . https://doi.org/ . /hts.v i . http://crossmark.crossref.org/dialog/?doi= . /hts.v i . =pdf&date_stamp= - - page of original research http://www.hts.org.za open access the increasing number of conferences and books on church leadership have an ambivalent effect on the image of the church leader. on the one hand, leadership is presented as something attractive; on the other hand, the expectations laid on church leaders have increased, not taking into account the fact that church eldership is usually voluntary, and voluntary church elders cannot invest as much time as leadership heroes like bill hybels and rick warren. in this article, the link between leadership and beauty is explored in an endeavour to rediscover the beauty of the church leadership office. timothy : speaks about church leadership. this article expands the topic to spiritual leadership, that is, leadership in the context of christian spirituality. this includes leading a church, but also leading church-oriented organisations like kindergartens and mission agencies. the research questions for this article are: what is beautiful about spiritual leadership, that is, why is it a beautiful task? why should spiritual leaders bother about beauty? the article starts with a short historical note about ‘the neglect of (theological) aesthetics’ section and ‘the great theory of beauty and its decline’ section. in the ‘theological aesthetics and transformation of the world’ section, four books are introduced that deal with the link between beauty and transformation of the world. after these introductory notes, the main part of the article (see ‘spiritual leadership and beauty’ section) attempts to answer the research questions. the section ‘a small poll’ reports on a small poll providing some evidence for the conclusions drawn in the ‘conclusions’ section. the neglect of (theological) aesthetics the french philosopher simone weil ( – ) was convinced that for many people in the th century the most natural way to find god was through beauty. ‘in everything which gives us the pure authentic feeling of beauty, there is the presence of god’ (weil : ). therefore, she criticised christianity for having so little to say about it (sherry : ). a more balanced view would take into account the fact that beauty may also lead in the opposite direction. ‘beauty is erotic and seductive, and can lead to idolatry; but it is also divine, and can lead to god and worship’ (de gruchy : ). at least beauty can lead to god. today, beauty is important on popular and social media, for example, television, facebook and instagram. however, we do lack a theory of beauty such as the greeks had (tatarkiewicz : ). according to the german philosopher wolfgang welsch, we are currently experiencing an ‘aesthetics boom’ but more as ‘surface aestheticization’ (in de gruchy : ). hans ulrich von balthasar ( – ), a catholic theologian from switzerland, was the first modern theologian to publish .for example, in kessler ( a: – ), it is explained how mathematical beauty may lead to the experience of spirituality. a voluminous work on theological aesthetics. the work was published from to and finally grew to seven volumes (von balthasar ). in the very first chapter, von balthasar ( a) argues that the three transcendentals – truth, goodness and beauty – are sisters not to be separated. if one destroys beauty, truth and goodness will perish along with it (von balthasar a: ). in a world without beauty, goodness would also lose its power of attraction, and the proofs of a true statement would lose their power of persuasion (von balthasar a: ). thus, according to von balthasar, aesthetics is essential if one wants to retain logic and ethics. otherwise one will arrive at the following exclamation: ‘truth is a lie, morality stinks, beauty is shit’ (in cilliers : ). in the catholic tradition, and especially in the orthodox tradition, the doctrine of the beauty of god is still alive; however, this topic is almost totally neglected within the protestant tradition (von balthasar a: , sherry : ). two major exceptions are jonathan edwards ( – ), the father of the so-called new england theology (sherry : – ), and karl barth ( – , switzerland), probably the most influential protestant theologian of the th century. in his church dogmatics, barth at least deals with the beauty of god (barth : – ), but he is still cautious about the term ‘god’s beauty’ and does not dare to treat it as a topic on its own. ‘we speak of god’s beauty only in explanation of his glory. it is, therefore, a subordinate and auxiliary idea’ (in ed. thiessen : ). for barth, beauty is an explanation of his glory and not its equivalent. by contrast, for von balthasar beauty is far more: it is transcendental and therefore a constituent of god’s glory. according to de gruchy ( : – ), this is the fundamental difference between balthasar’s aesthetics and barth’s aesthetics. the new england theologian jonathan edwards tied his discussion of aesthetics to the role of the spirit within the trinity as a beautifier (sherry : ). the ‘spiritual leadership and beauty’ section returns to this topic. one reason why theological aesthetics was neglected in protestant theology is that protestantism stresses the ‘theology of the cross’, and that seemed to be incompatible with aesthetics. some theologians demonstrate that both perspectives can be brought together. actually, von balthasar and barth in their aesthetical approach proclaim the beauty of the cross (de gruchy : ). von balthasar calls it ‘the most sublime of beauties – a beauty crowned with thorns and crucified’. according to cilliers ( : ) ‘the ugliness of the cross is the strange “beauty” of god’. ‘through the lens of faith the ugliness of the cross is transformed into a different type of beauty’ (cilliers : ). thus, a theology of the cross does not necessarily exclude theological aesthetics. .as a matter of fact, neither von balthasar nor barth quote edwards. von balthasar ( a: ) erroneously named karl barth as the first protestant theologian to deal with god’s beauty (de gruchy : ). .english quote from de gruchy ( : ). .the german theologian jürgen moltmann discusses the ‘glory of the crucified god’ (in ed. thiessen : ). he argues for a redefinition of beauty, because the holy http://www.hts.org.za� page of original research http://www.hts.org.za open access another reason for the neglect of aesthetics is the fact that there is no longer a theory of beauty – which leads us to the next section. the great theory of beauty and its decline the title of this section is borrowed from the polish philosopher tatarkiewicz ( ), who wrote a concise survey on this theory. umberto eco ( – , italy), a professor of literature and author of historical novels, published a ‘beautiful’ book the history of beauty. in this book, eco ( ) provides a number of sources for the understanding of beauty in different epochs. in classical greek culture, beauty was ‘all that pleases, arouses admiration, or draws the eye’ (eco : . ). two aspects are to be mentioned. harmony and proportion tatarkiewicz ( : ) wrote about ‘the great theory of european aesthetics’, which he defined as follows: ‘beauty consists…in the proportions and arrangement of the parts’ (tatarkiewicz : ), harmonia and symmetria. this great theory was initiated by the pythagoreans. they found the properties and relations of harmony in numbers (tatarkiewicz : ). ‘pythagoras marks the birth of an aesthetic- mathematical view of the universe’ (eco : ). plato took over the pythagorean idea that beauty consists of ‘harmony and proportion’ (eco : ). today, some elements of this understanding of beauty are still recognisable in the discussions about the golden ratio (corbalán ). functional beauty according to plato’s contemporary xenophon, something is beautiful if it fits its purpose. this is the functional aspect of beauty. ‘beauty consists in the adequacy of things to their purpose’ (tatarkiewicz : ). if something is dysfunctional or does not serve its purpose, it cannot be beautiful. in this sense, a crystal hammer is ugly because the material does not conform with the purpose of a hammer (eco : ). these connotations are probably behind the use of the word kalos in timothy : : the task is kalos (i.e. beautiful and good) if it fits its purpose, the purpose of the church. the great theory of beauty was then further developed by augustine, thomas aquinas and others. but it is no longer considered valid; its decline started in the th century (tatarkiewicz : ). the challenge is that today there is spirit, who is the beauty of god, was present with christ in the ugliness of the cross (van den bosch : ). .plato, in his work symposium, speaks about the ‘glance’ that sees ‘true beauty, the divine beauty’ (eco : ), which he connects to virtue and truth. here we see the above-mentioned troika: ‘the true, the good and the beautiful’. .‘if therefore a thing is well-suited to its purpose with respect to this, it is beautiful and good’. this wording probably goes back to xenophon’s teacher socrates. .this functional aspect used to be a supplement to the great theory; it became independent only in the th century (tatarkiewicz : ). no theory in sight to fill the empty space after the decline of the great theory of beauty. ‘the word and concept beauty have been retained in colloquial speech; however, they are used in practice rather than in theory’ (tatarkiewicz : ). eco ( : ) argues that ‘beauty has never been absolute and immutable but has taken on different aspects depending on the historical period and the country’. a practical example of this statement was provided by the journalist esther honig, who conducted an interesting study in . she sent a photo of herself to various people in different countries asking them to make her look beautiful using photoshop. the results demonstrate that on the one hand, ideals of beauty vary from country to country; on the other hand, they still have some things in common (gofeminin ). theological aesthetics and transformation of the world there are some publications on the link between leadership and aesthetics. for example, the polish authors hatch, kostera and kozminski ( : – ) write about ‘the aesthetic of leadership’; hansen, ropo and sauer ( ) deal with ‘aesthetic leadership’ and provide a good survey of literature on this topic. because the focus here is on the theological aspects of aesthetics, this section discusses four theological books dealing with aesthetics and transformation of the world. bohren: practical theology as theological aesthetics the practical theologian rudolf bohren ( – ) was of swiss origin but spent most of his academic career in germany, especially in heidelberg. in his book god becomes beautiful (dass gott schön werde), bohren ( ) lays the groundwork for his understanding of practical theology. the title is surprising because it refers to the future rather than the present. usually, we would say: ‘god is already beautiful’ and not ‘god becomes beautiful’. bohren’s approach is pneumatological, founded on the work of the spirit. because the spirit is a recreator, a pneumatological practical theology must be future-oriented – looking at the new earth and the new city (bohren : ). practical theology reflects ‘god becoming practical’, which is understood in the aesthetic sense of ‘god becoming beautiful’ (bohren : ). thus bohren ( : ) describes practical theology as ‘theological aesthetics’ (the subtitle of his book), which has the task of shaping the world according to the laws of beauty. bohren ( : – ) contrasts the ‘laws of beauty’ with ‘the law of ugliness’, which entered the world in the fall. thus bohren’s approach ‘is about the beautification of god in the midst of … ugliness’ (cilliers : ). .‘praktische theologie gilt demnach der formierung der welt nach den gesetzen der schönheit’ (bohren : ). .because bohren’s work was never translated into english, he is nearly ignored outside the german-speaking countries. the dutch author heitink ( : ) and the south african author cilliers ( : ) are the only references i am aware of. neither is bohren’s work mentioned in thiessen’s reader on theological aesthetics, nor by sherry ( ) or de gruchy ( ), although the latter came to conclusions similar to bohren. http://www.hts.org.za� page of original research http://www.hts.org.za open access sherry: the holy spirit and beauty in , the british theologian patrick sherry published his book spirit and beauty ( ), exploring the links between the holy spirit and beauty – another neglected area of discussion. as sherry ( : ) points out, typically two links between the spirit and beauty are discussed: ( ) the role of the spirit in creation (gn : ) and ( ) artistic talents as gifts of the holy spirit, for example, in the craftsman bezalel (ex : – ). in addition, sherry places a strong emphasis on the spirit’s role as a beautifier (see below). sherry ( : ) then discusses the role of the spirit in the final transfiguration of the cosmos, indicated by psalm : : ‘[w]hen you send forth your spirit, they are created, and you renew the face of the earth’. thus sherry ( ), like bohren, emphasises the eschatological role of the spirit and of beauty: [b]eauty has an eschatological significance, that in it we glimpse the future transfiguration of the cosmos which is symbolized in the new jerusalem and the new heaven and earth prophesied in the book of revelation (anticipated by isa. : ). (p. ) de gruchy: theological aesthetics in the struggle for justice in , the south african theologian john w. de gruchy (cape town) published a voluminous book christianity, art and transformation. de gruchy ( : ) sees a connection between ugliness and oppression, and between beauty and redemption. thus his focus in this book is ‘the redemptive power of beauty’ (de gruchy : – ), the contribution of aesthetics to the process of societal transformation. de gruchy ( ) emphasises the unique contribution of theology to aesthetics: theological aesthetics is not a sub-discipline of philosophical aesthetics, but an enquiry that assumes the biblical grand narrative of creation and redemption, of paradise lost and paradise regained, of incarnation, death and resurrection, of the gift of the spirit and the hope of a ‘new heaven and earth’. (p. ) many people consider aesthetics as a sort of luxury, pursued and enjoyed by the elite only. thus, de gruchy ( : ) clearly states: ‘theological aesthetics does not encourage flight from the world but assumes christian participation in god’s mission to transform the world’. as evidence, the example of archbishop desmond tutu is mentioned and how he was attracted to the icon of the transfiguration (mt : – ). de gruchy ( ) states: in the midst of the ugliness of apartheid and the struggle to bring about its downfall, the icon of transfiguration opened a window of hope through which the transformation of south africa could be anticipated. (p. ). .sherry concedes that the east has ‘done more to develop a theology of beauty specifically related to the holy spirit’ (sherry : ) and that ‘many eastern theologians connect the holy spirit’s role as beautifier with his function of manifesting the word’ (sherry : ). .de gruchy ( : ) argues that also in the case of von balthasar ‘his theological aesthetics did not imply any withdrawal from the need to work for justice in the world’. de gruchy calls this the ‘transfiguration spirituality’, that is ‘the spirituality of seeing the splendour of god even in the midst of ugliness and pain’ (de gruchy : ). this spirituality is transformative and ‘can only be understood in the light of the gift of the spirit’ (de gruchy : ). boren: the beauty of god’s mission us theologian scott boren completed a doctoral thesis on the ‘missional church and missional leadership in the light of theological aesthetics’ (boren : subtitle). his research question was ‘how has the theological aesthetics informed the way missional pastors lead?’ (boren : ). boren conducted an empirical study by interviewing four pastoral leaders who espoused ‘the view of missional church as triune participation’ (boren : ). one motivation for his research was the observation that sometimes christian leaders are so convinced of the truth and goodness of the missional approach that they ‘end up forcing people in that direction, often using guilt, shame, and manipulation’ (boren : ). boren ( ) is convinced that this happens if theological aesthetics is neglected. in his ( ) concluding section, he argues: the movement toward missional church depends…upon the church and its leaders’ capacity to participate in the telos of beauty. this fosters a way of leadership that is in and of itself beautiful… (p. ) spiritual leadership and beauty this section provides a theoretical theological answer to the research question about the link between spiritual leadership and beauty. it draws heavily from the above-mentioned works of bohren, de gruchy and sherry. spiritual leaders are beautifying the church and beyond the first thesis of this article is that spiritual leaders are beautifying the church and beyond. this conclusion has to be developed in four steps: . the spirit is the real leader of the church in , bohren gave a lecture about church leadership (reprinted in bohren ). he raised the question: ‘who leads the church?’ with reference to john : , bohren ( : ) argues that the holy spirit leads the church. the seven letters of revelation are dictated by the risen christ but they end with the words: ‘hear what the spirit says to the churches’ (rv : , , , ; : , , ). christ is the head of the church (col : ) but because christ sits next to his father, he reigns over his church via the spirit until he returns to the earth (bohren : ). at first glance, this distinction might look like nit-picking because, after all, the spirit and christ belong to the trinity. but bohren ( : , – ) lists some practical implications of this change of perspective. http://www.hts.org.za� page of original research http://www.hts.org.za open access . church leaders are partaking in the work of the spirit the german theologians böhlemann and herbst ( ) published a handbook on church leadership entitled ‘spiritual leading’. in their definition of spiritual leadership, they refer to bohren’s teaching: ‘spiritual leadership is leadership through the holy spirit, executed…by the leaders installed by the holy spirit’. according to this definition, the connection between church leadership and the spirit already starts with the selection process. there are many organisational ways of finding new leaders in the church, but whatever process we use, we trust (hope) that ultimately these leaders have been chosen by the spirit (ac : : ‘in which the holy spirit made you overseers’). furthermore, the spirit distributes gifts in connection with leadership (e.g. cor : , eph : ). so we may conclude that the spirit chooses the church leaders and enables them to exercise the leadership task. these leaders should be aware that the spirit is the leader of the church and that in their task of leading the church, they have the privilege of participating in the work of the spirit. . the spirit is beautifying the church and beyond already the reformer john calvin wrote about the beautifying work of the spirit. with reference to genesis : , calvin ( ; cf. sherry : ) concluded: [f]or it shows not only that the beauty which the world displays is maintained by the invigorating power of the spirit, but that even before this beauty existed the spirit was at work cherishing the confused mass. (institutio, i. § ) in his discourse on the trinity, john edwards describes various offices of the spirit, one of which is to ‘beautify all things’ (n.d.: ). edwards then refers to job : : ‘by his spirit garnished the heavens’. both bohren ( ) and sherry ( ) place great emphasis on the fact that the spirit is beautifying the world. bohren ( : – ) mentions four areas in which god’s spirit works according to the laws of beauty, against the law of ugliness: creation, culture and arts, history and the church. sherry ( : ) even uses the noun ‘the spirit as beautifier’. he does so in analogy to the well-known phrase ‘the spirit as perfecter’ (sherry : ), used by st. gregory of nazianzus ( : ). as noted above, both bohren and sherry emphasise the eschatological dimension of beautifying. from the statements, ( ) the spirit is the real leader of the church, ( ) church leaders are partaking in the work of the spirit and ( ) the spirit is beautifying the church and beyond, we can draw the following conclusion. .german original: ‘geistliche leitung ist leitung durch den göttlichen geist, vollzogen in der gemeinschaft der heiligen durch die vom geist eingesetzte leitung’ (böhlemann & herbst : ). .von balthasar ( b: – ) speaks about the spirit as ‘glorifier’, glorifying jesus christ. .sherry argues that this is a concept he found in theologies of different times and places: early alexandria, th century new england and th century russian orthodoxy (sherry : ). . spiritual leaders are beautifying the church and beyond so far, this is a theological statement and not a phenomenological one. unfortunately, this statement is not true for every spiritual leader. there are, for example, spiritual leaders, who, in their pursuit of power, make the world uglier than before (kessler & kessler ; kessler b). how can this statement ( ) become visible? leaders usually want to improve the organisation they are leading. they envisage a situation that is better than the current situation and take steps to move towards this situation. by doing this, they beautify the organisation and the context in which they work. it was noted previously that leaders need spiritual gifts in order to exercise their leadership task. ‘the spiritual gift has the mission to form the world and the church according to the laws of beauty’. spiritual leaders should strive for beauty it is taken for granted that church leaders should ‘be fellow workers for the truth’ ( john ). it is also expected that they strive for goodness by being good role models (see, e.g., the above-mentioned list of virtues in tm and tt ). the second thesis of this article is: spiritual leaders should strive for beauty as diligently as they strive for truth and goodness. as von balthasar ( a: ) rightly observes, the troika (truth, goodness and beauty) cannot be separated. therefore, leaders have to deal with beauty because otherwise truth and goodness will also be forfeited. de gruchy ( ), taking up balthasar’s statement about the inseparability of the troika, puts it this way: truth without goodness and beauty degenerates into dogmatism, and lacks the power to attract and convince; goodness without truth is superficial, and without beauty … it degenerates into moralism. alternatively, we could say that truth and goodness without beauty lack power to convince and therefore to save. (p. ) what does this statement mean in practice? de gruchy ( : ) believes in the transformational potential of the arts and their importance for christian praxis and provides many examples from south africa and beyond. boren ( : – ) identifies some ways pastoral leadership can work towards the goal of missional beauty. hanna schrenk, a student at our academy of christian leadership, pointed out another application of ‘leaders should strive for beauty’. hanna leads a kindergarten in southern germany. they started to transform their rooms towards a certain aesthetic ideal. one reason is that today in germany children spend much more time in the kindergarten than they did a decade ago. it used to be in the mornings only, but today it is often from : to : (hollmann : ). thus, the kindergarten rooms have a greater influence on the children’s development than in the past. in an aesthetic .‘das charisma hat die aufgabe, welt und gemeinde nach den gesetzen der schönheit zu gestalten’ (bohren : ). .also quoted in boren ( : ). http://www.hts.org.za� page of original research http://www.hts.org.za open access environment, children would develop more motivation and enjoyment of life (hollmann : ). their aesthetic ideal is to ‘clear the rooms’ (‘räume klären’). this means first to tidy up the rooms and then to transform them into clear and transparent spaces (‘less is more’), but also to create certain stimuli for the children. in an aesthetic environment, the kindergarten children develop an intrinsic motivation to keep order. thus, aesthetics obviously has an influence on moral development. the aesthetic aspect of leadership cannot be reduced to decorative elements like putting flowers and nice candles on the table. it is a much more holistic approach. thus, it is an essential part of leadership and cannot be completely delegated to somebody outside the leadership team, just as true teaching cannot be outsourced (e.g. see ac : ). a small poll methodology in germany, we have a biennial conference on christian leadership (www.kcf.de). there are about attendees from the business world, churches, christian non- government organisations, etc. during kcf in karlsruhe, february– march , we conducted a survey with the following two questions: ( ) what is beautiful about leading? and ( ) what is not beautiful about leading? this little ‘survey’ (strictly speaking, we were just collecting some answers) was not restricted to spiritual leaders. we can assume that the participants of kcf identified with the christian perspective of the congress, but most of them had secular jobs. thus, we put the question about leadership quite generally and did not distinguish between different branches or between paid and voluntary leadership positions. we kept it simple because we were looking for spontaneous answers. we just provided the bible verse timothy : and asked the two above-mentioned questions. the participants wrote their answers on small index cards and put them into two different boxes ( beautiful and not beautiful). some participants just wrote one issue on one card and others wrote several issues on one card. as far as we could tell from the handwriting, only one person put two cards into box b. results on the question ‘what is beautiful about leading?’ we collected index cards on the first question. the highest score was given to ‘human beings’ ( times). leaders enjoy working together with other people, and they especially enjoy it when they can empower other people by finding their strengths and then supporting them (mentioned times). they enjoy it when people grow. the apostle paul obviously also knew about this joy. he wrote to the thessalonians: ‘for you are our glory and our joy’ ( th : , cf. phlp : ). .there is some parallel to calvin’s explanation of genesis : : first the spirit had to contend with the tohubohu and then the spirit created something clear, functional, meaningful and beautiful. the second highest score was for the opportunity to shape the future. actually, participants used the german word ‘gestalten’ (shape). in germany, people do not like the word ‘power’ and often use the word ‘shaping’ instead. eleven index cards mentioned ‘responsibility’ as a beautiful facet of leadership (which is interesting, because this was also a topic on the negative side – see below). twelve index cards had an explicit link to god or jesus. they mentioned that it is beautiful to have a task from god, to work for god’s honour, to participate in god’s work. one expected a reward in heaven. one participant mentioned the opportunity ‘to observe god at work’. results on the question ‘what is not beautiful about leading?’ we collected index cards on this question. the highest score went to pressure and stress ( times). leaders have to work hard, and they often have to work more than others. the second highest score was for the issue of responsibility ( times), amongst which was to take responsibility for hard and nasty decisions. the third highest score was for the social isolation of leaders (six times). although many leaders like to work with people (see above), they know about the loneliness of leaders. conclusions firstly, beauty is as important as truth and goodness. thus, leaders should strive for beauty as diligently as they strive for truth and goodness. the leadership task cannot be completely delegated to people outside the leadership team. secondly, spiritual leadership is a beautiful task because spiritual leaders are beautifying the church and beyond. they partake in the work of the spirit, who is a beautifier. this has a future-oriented, eschatological dimension: leading into a better, more beautiful world. this is not to be understood in a naïve way. christian leaders often deal with the ugliness of the world, amidst chaos, crime, corruption, abuse of power, etc. but in their service they contribute to the beautification of the world, working against the ‘law of ugliness’ (bohren : ). in practice, the beauty of leadership can be experienced in different ways, for example, by helping people grow, by seeing beautiful results or, as one participant in the survey put it, ‘by observing god at work’ and being part of it. acknowledgements competing interests the author declares that he has no financial or personal relationships that may have inappropriately influenced him in writing this article. author’s contributions v.k. is the sole author of this research article. http://www.hts.org.za� www.kcf.de� page of original research http://www.hts.org.za open access ethical considerations this article followed all ethical standards for research without direct contact with human or animal subjects. funding information the research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. data availability statement data sharing is not applicable to this article as no new data were created or analysed in this study. disclaimer the views and 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[ – ]. the knowledge of divine proportion exists since ancient greek sculptor phidias, and it was firstly scientifically described by filius bonacci, discoverer of the numerical value of the divine proportions [ ]. more relevant to the dental profession as well as the medical profession (such as plastic surgeons) are the divine proportions of the human face. hindawi publishing corporation e scientific world journal volume , article id , pages http://dx.doi.org/ . / / http://dx.doi.org/ . / / the scientific world journal tr ln me lc sto me . . . . (a) . . / / (b) figure : lengths of the face and set of ideal proportions. this particularly applies to the orthodontic treatment given that the objectives to be achieved at the end of the treatment are not only functional stability, but also facial esthetic improvement [ ]. the aim of our paper was to try to establish objective facial features which are widely considered as beautiful. therefore, specific aims of this paper were the following: ( ) to compare the facial proportions of two groups of females (anonymous and attractive) in order to establish the difference between them, ( ) to determine the deviation from the values of ideal proportions (ratio : . ) in both groups, ( ) to compare the difference between facial parameters representing facial height and width in both groups. . methods the study comprised two groups. first group consisted of female subjects between and years of age who were selected from the population of medical and dental students at the university of belgrade, and the second group included attractive celebrity females (popular models and actresses). celebrities whose photos were used in this study were mostly models and actresses whose facial beauty was studied closely by the experts in the field of plastic surgery, and among them are those who were named as most beautiful and most proportional faces by the beauty and fashion magazines (such as vogue, cosmopolitan, and new woman). the en face facial photographs were taken in natural head position (nhp), using camera canon power shot g , . mp, with the same distance of . m. after training and calibration, all measurements on photographs were performed by the first author (jovana milutinovic). in order to test the feasibility and reproducibility of the measurements, photographs ( % from each group) were selected and reassessed by the same author, two months after the initial assessment. therefore, to evaluate intra-observer agreement, cohen’s kappa test was applied following the instructions by landis and koch [ ]. the soft tissue points used for obtaining linear distances which were measured are shown in table . in the photographs, the following parameters were mea- sured: ( ) lengths of the face (figures (a) and (b)): (i) (tr-me): height of the face, (ii) (lchk r-lchk l): width of the face, (iii) (me-sto): the lowest point on the chin and the point where the upper and lower lip merge, (iv) (sto-lc): the point where the upper and lower lip merge and corner of the eye, the scientific world journal table : soft tissue points. point clarification trichion (tr) the beginning of the forehead when one lifts the eyebrow glabella (gl) the most prominent point of the forehead at the superior aspect of the eyebrows subnasale (subn) point in the midsagittal plane where the nasal septum merges into the upper lip menton (me) the most inferior point on the soft tissue chin stomion (sto) midpoint of the intralabial fissure postaurale (pa) the most posterior point on the helix (outer rim of the ear) exocanthion (ex) most lateral point of the palpebral fissure at the outer canthus of the eye endocanthion (en) most medial point of the palpebral fissure at the inner canthus of the eye cheilion (ch) corner of the mouth lateral canthus (lc) lateral canthus of the eye lateral nose (ln) lateral side of the nose lateral cheek (lchk) lateral border of the cheeks (v) (me-ln): the lowest point on the chin and the outer edge of the nostril, (vi) (ln-tr): the outer edge of the nostril and highest point of the forehead; ( ) division of the face: (a) the horizontal thirds of the face (figure ): ( ) upper third: tr-gl, ( ) middle third: gl-subn, ( ) lower third: subn-me; (b) vertical fifths of the face (figure ) ( ) pa r-ex r, ( ) ex r-en r, ( ) en r-en l, ( ) en l-ex l, ( ) ex l-pa l; ( ) the ideal proportions: after marking and connecting points needed to obtain adequate lengths, measured parameters were compared with the ideal set of proportions ( : . ): (i) the ratio lchk r-lchk l : tr-me is expected to be : . (figure (b)), (ii) the ratio sto-me : sto-lc is expected to be : . (figure (a)), (iii) the ratio me-ln : ln-tr is expected to be : . (figure (a)), (iv) the ratio subn-sto : subn-me should be : [ ], lower facial third index, that could also be shown in percentage ( : %) [ ] (fig- ure (b)). for each and every parameter the ratio between them was used, so that the actual length of the measured parameters was of no importance. tr gl subn me upper floor middle floor lower floor figure : division of the face into horizontal thirds. . statistical analysis statistical analyses were performed using spss for windows, version . the kolmogorov-smirnov test was applied in order to test whether the data distribution fits probability density function also known as gaussian function or bell curve. subsequently, if test had not rejected the assumed normal distribution, the parametric tests would have been used. for testing the differences in all parameter values between groups, independent sample 𝑡-test was used. for analyzing the similarity of vertical thirds and horizontal fifths of the face, in each group one-way anova test was applied and in cases where anova showed statistically significant the scientific world journal table : length parameters of the face for attractive and anonymous females. group mean (mm) std. dev. std. error mean 𝑡-test trichion-glabella anonymous females . . . . attractive females . . . glabella-subnasale anonymous females . . . . attractive females . . . subnasale-menton anonymous females . . . . attractive females . . . subnasale-stomion anonymous females . . . . attractive females . . . menton-stomion anonymous females . . . . attractive females . . . stomion-lateral canthus anonymous females . . . . attractive females . . . menton-lateral nose anonymous females . . . . attractive females . . . lateral nose-trichion anonymous females . . . . attractive females . . . lateral nose-lateral nose anonymous females . . . . attractive females . . . cheilion-cheilion anonymous females . . . . attractive females . . . lateral canthus-lateral canthus anonymous females . . . . attractive females . . . lateral cheek-lateral cheek anonymous females . . . . attractive females . . . trichion-menton anonymous females . . . . attractive females . . . pa r ex r en r en l ex l pa l figure : division of the face into vertical fifths. difference between parameters post hoc bonferroni test for multiple comparison was applied. to compare differences between ideal proportions and obtained proportions of the facial parameters, the authors applied paired samples 𝑡-test which analyzed the both values in each subject according to the concept where every particular value has its own paired “control” value. in all analyses, the significance level was set at . . . results the kolmogorov-smirnov test showed normality of distri- bution of the obtained data in both groups. the kappa coefficient ranged from . to . which is considered to be substantial to almost perfect agreement [ ]. the mean measurement values representing length parameters of the face for both groups are shown in table as well as the differences between two groups. almost all parameters were significantly smaller in the group of attractive females. tables (a) and (b) show the divisions of the face into horizontal thirds and vertical fifths for both groups. one-way anova showed difference between horizontal thirds and between vertical fifths in the group of anonymous females, the scientific world journal table : (a) division of the face into horizontal thirds. (b) division of the face into vertical fifths. (a) horizontal thirds mean std. dev. anova post hoc multiple comparison bonferroni test sig. anonymous females . . versus . . . . . versus . . . . versus . . versus . . attractive females . . . . . . . : trichion-glabella, : glabella-subnasale, and : subnasale-menton. (b) vertical fifths mean (mm) std. dev. anova post hoc multiple comparison bonferroni test sig. anonymous females . . versus . ∗ . versus . ∗ . versus . ∗ . versus − . . . . versus . ∗ . versus . . versus − . . versus . ∗ . . . . versus . ∗ . versus − . . versus − . . versus . ∗ . . . versus . ∗ . versus . . versus . . versus . ∗ . . . versus − . . versus . ∗ . versus . ∗ . versus . ∗ . attractive females . . . . . . . . . . . : postaurale right-exocanthion right, : exocanthion right-endocanthion right, : endocanthion right-endocanthion left, : endocanthion left-exocanthion left, and : exocanthion left-postaurale left. ∗statistical significance. the scientific world journal table : the differences between ideal proportions and obtained proportions of the facial parameters. paired differences between measured and ideal values paired samples 𝑡-test group mean (mm) std. dev. sig. subnasale-stomion attractive females . . . anonymous females . . . stomion-lateral canthus attractive females . . . anonymous females − . . . lateral nose-trichion attractive females − . . . anonymous females − . . . lateral canthus-lateral canthus attractive females . . . anonymous females − . . . cheilion-cheilion attractive females − . . . anonymous females − . . . trichion-menton attractive females − . . . anonymous females − . . . while in the attractive females group facial thirds and fifths were equal, with no statistical difference. using multiple comparison test in the group of anony- mous females (tables (a) and (b)), distance postaurale- exocanthion (pa-ex), or the most lateral fifth of the face presented by the earlobe section of the face, was found to be significantly smaller than medial three vertical fifths of the face. however, st and th vertical fifths were not signif- icantly different one from another. likewise, the significant difference for the middle third in comparison with the st and rd thirds of the face was found in the group of anonymous females as it was also significantly smaller. there was no significant difference between st and rd thirds. parameters representing division of the lower third of the face into two lengths, upper distance from the point subnasale to stomion, or the thickness of the upper lip, and lower distance from the point stomion and menton, which are supposed to be in relation / : / , satisfied this criterion in the group of attractive females but not in the group of anonymous females. table refers to the comparison of the differences between ideal proportions and obtained proportions of the facial parameters. to compare these values, the authors applied paired samples 𝑡-test. all analyzed parameters were found to be statistically different from the ratio : . in the group of anonymous females. however, in the group of attractive females, three out of six parameters (subn-sto, sto- lc, and ln-tr) correspond to ideal ratio. . discussion the aim of this investigation was to evaluate the difference in facial proportions between attractive and anonymous caucasian females. comprehension and analysis of facial parameters are necessary in different fields of medicine and dentistry, espe- cially among specialists like plastic surgeons, maxillofacial surgeons, orthodontists, and prosthodontists [ , ]. keeping that in mind, there is a need for clinicians who work in a maxillofacial region to understand and become familiar with guidelines for esthetic standards and parameters of the soft tissue [ , , ]. bashour [ ] found that there are four most impor- tant cues determining attractiveness: averageness, sexual dimorphism, youthfulness, and symmetry. he pointed out that a surgeon who is planning facial cosmetic, plastic, or reconstructive surgery can potentially gain both profound comprehension and better quality surgical results by appre- ciating these findings. division of the face into thirds and fifths is commonly used photogrammetric method for assessing facial symmetry. in our study, all of these measures were uniform in the group of attractive females. in , sforza et al. examined the difference between two groups of women, attractive ones with “normal” (healthy reference women), and obtained similar results [ ]. attractive females had several “neonatal” characteristics, such as relatively large forehead and a rounded and smaller face in general; they stated that “babyness” is the characteristic that separates them from the normal group. in our research, attractive females also had a smaller face, considering majority of parameters of the face. mack [ ] was the first to demonstrate the practical appli- cation of ideal proportions for improving facial aesthetics. he discussed the importance of treating the dentition to the face based on the divine proportion. according to him, the lower / of the face significantly influences facial appearance. as proof, he stresses the public’s preoccupation with fullness of the lips and the importance of a pleasing smile. these so-called vitruvian thirds [ ] in the lower face have to be adjusted to a % upper lip, % lower lip-chin proportion. in our study, attractive group showed harmonized lower third of the face, with lower facial index (subnasale-stomion, stomion-menton) in accordance with this beauty cannon ( % : %). therefore, this ideal ratio should be suitable in planning concept for treatment in facial region [ ]. these distances and divisions in the lower third of the face are one of the most important in the evaluation of facial beauty, given the scientific world journal the fact that the lips and the chin highly determinate female beauty [ , ]. women lips are very impressionable feature of the face and have a strong influence on facial beauty perception. various studies (bisson and grobbelaar, , ward, , torsello et al., , mommaerts and moerenhout, , and anic-milosevic, ), in which authors analyzed the lower third of the face and the lips, stated that these are one of the five important characteristics in female facial aesthetics [ – ]. ferrario et al. ( ) reported that attractive women share several similar characteristics, such as increased upper facial third (forehead), smaller face, and more voluminous (thicker) lips than nonattractive ones. in addition, it was stressed that the length of the nose was therefore smaller in attractive group. in their research, they compared attractive and normal women and stated that facial characteristics of attractive females showed uniformity, while facial parameters in a normal group differed from ideal proportions [ ]. in the study of hall et al. [ ] it was shown that thickness of the lips was one of the main features in the beauty perception based on a poll among orthodontists and lay public. perseo [ ] stated that, in some cases, standard camera distortions in cinema images made certain female faces appear more beautiful because they are overall “shortened.” the studies of several authors have obtained the same results [ – ]. in the present investigation, the values for vertical length parameters, such as distance between points me-ch and ch-lc as well as me-ln and ln-tr, which should be in relation determined by ideal proportions, differed in the group of anonymous female group. therefore, faces of famous attractive females who represent contemporary canons of beauty are closer to the ideal proportions [ ]. the question that always seems to intrigue scientists deal- ing with facial beauty is timelessness of the beauty principles established centuries ago. torsello et al. ( ) found that some of the neoclassical canons can be considered still valid, while others seem to be changed over centuries. according to their research, it seems that reductions in facial medium third, in distance between eyes, and in nose dimensions have occurred as well as relative enlargement of eyes and mouth width [ ]. mommaerts and moerenhout ( ) showed in their research that some of the ancient and neoclassical canons of beauty are still unchanged, despite the fact that some of these canons were established years ago. these guidelines considering facial beauty can be used for improving patient’s facial appearance. clinicians must be aware that each and every person has their own beauty perception, so these results should be viewed with caution. . conclusions facial beauty and its determiners are one of the most arguable topics among surgeons, dentists, and orthodontists. they can all agree about some objective guidelines concerning facial proportions, symmetry, and ratio between specific facial parameters. however, more subjective understanding of beauty is still immeasurable and lies in the eye of beholder. this study showed significant difference between anony- mous and attractive females. attractive females showed smaller face in general and uniformity of the facial thirds and fifths, and most of the facial parameters meet the criteria of the ideal proportions. conflict of interests the authors declare that there is no conflict of interests regarding the publication of this paper. acknowledgment this study is supported by the ministry of science and education of the republic of serbia, grant no. . references [ ] s. a. milošević, m. l. varga, m. šlaj et al., “analysis of the soft tissue facial profile of croatians using of linear measurements,” journal of craniofacial surgery, vol. , no. , pp. – , . 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[ ] n. c. springer, c. chang, h. w. fields et al., “smile esthet- ics from the layperson’s perspective,” american journal of orthodontics and dentofacial orthopedics, vol. , no. , pp. e –e , . gaussian guesswork ....... .... or why . . . . is such a beautiful number article author: adrian rice math horizons, november , pp. — . doi . / x . “before theorems are proved, conjectures must be made, . . . ” “before theorems are proved, conjectures must be made, . . . ” . . . and for that to happen, all kinds of experimentation, observation, invention and, indeed, imagination must come into play.” carl friedrich gauss ( - ) • one of the most creative mathematicians of all time (alongside archimedes and newton). carl friedrich gauss ( - ) • one of the most creative mathematicians of all time (alongside archimedes and newton). • kept a “mathematical diary” for nearly years (just before his th birthday in until july ) gauss’ may , discovery: amazing relationship between three particular numbers: • a sophisticated form of average • a particular value of an elliptic integral • the ratio of the circumference of a circle to its diameter (π) some of what gauss knew about π • π ∼= . etc. some of what gauss knew about π • π ∼= . etc. • π = ∫ dt √ − t (arclength of semi-circle) some of what gauss knew about π • π ∼= . etc. • π = ∫ dt √ − t (arclength of semi-circle) • if u = ∫ x dt √ − t , then x = sin u . . . some of what gauss knew about π • π ∼= . etc. • π = ∫ dt √ − t (arclength of semi-circle) • if u = ∫ x dt √ − t , then x = sin u . . . . . . and sin(u + π) = sin u. hmmmmmm . . . . . . what happens with similar integrals????? if u = ∫ x dt √ − tn , then x = . . . january : begins to investigate case of n = : ∫ x dt √ − t january : begins to investigate case of n = : ∫ x dt √ − t cool! arclength of lemniscate curve: (x + y ) = x − y january : begins to investigate case of n = : ∫ x dt √ − t cool! arclength of lemniscate curve: (x + y ) = x − y follow the sin u pattern to define a leminiscate sine!!! • if u = ∫ x dt √ − t , then x = sin u. • if u = ∫ x dt √ − t , then x = slu. • if u = ∫ x dt √ − t , then x = sin u. sin(u + π) = sin u , where π = ∫ dt √ − t . • if u = ∫ x dt √ − t , then x = sl u. • if u = ∫ x dt √ − t , then x = sin u. sin(u + π) = sin u , where π = ∫ dt √ − t . • if u = ∫ x dt √ − t , then x = sl u. sl (u + ω) = sl u , where ω = ∫ dt √ − t . • if u = ∫ x dt √ − t , then x = sin u. sin(u + π) = sin u , where π = ∫ dt √ − t . • if u = ∫ x dt √ − t , then x = sl u. sl (u + ω) = sl u , where ω = ∫ dt √ − t . ω = . etc. gauss’ may , discovery: amazing relationship between three particular numbers: • the ratio of the circumference of a circle to its diameter: π gauss’ may , discovery: amazing relationship between three particular numbers: • the ratio of the circumference of a circle to its diameter: π • a particular value of an elliptic integral: ω = ∫ dt √ − t gauss’ may , discovery: amazing relationship between three particular numbers: • the ratio of the circumference of a circle to its diameter: π • a particular value of an elliptic integral: ω = ∫ dt √ − t • a sophisticated form of average the arithmetic-geometric mean of a, b define two sequences: n = : a = a b = b n = : a = (a + b ) b = √ a b n ≥ : an = (an− + bn− ) bn = √ an− bn− facts about (an), (bn) for a, b ≥ • both sequences converge. facts about (an), (bn) for a, b ≥ • both sequences converge. • lim n→∞ an = lim n→∞ bn facts about (an), (bn) for a, b ≥ • both sequences converge. • lim n→∞ an = lim n→∞ bn call this limit the arithmetic-geometric mean of a, b: m(a, b) = lim n→∞ an = lim n→∞ bn why . etc is a beautiful number we have established that the arithmetic-geometric mean between and √ is π/ω to places; the proof of this fact will certainly open up a new field of analysis. gauss’s diary, may , may - gauss completes the proof lemma . let a, b > , a = a , b = b and set i(a, b) = ∫ π/ dq√ a cos q + b sin q . then i(a, b) = i ( a+b , √ ab ) may - proof complete! lemma . let a, b > , a = a , b = b and set i(a, b) = ∫ π/ dq√ a cos q + b sin q . then i(a, b) = i ( a+b , √ ab ) lemma . i(a, b) = π/ m(a, b) . may - proof complete! lemma . let a, b > , a = a , b = b and set i(a, b) = ∫ π/ dq√ a cos q + b sin q . then i(a, b) = i ( a+b , √ ab ) lemma . i(a, b) = π/ m(a, b) . theorem. m( , √ ) = πω. further reading j. m. borwein and p. b. borwein, pi and the agm (john wiley & sons, ) d. bressoud a radical approach to real analysis (maa, ). d. a. cox, the arithmetic-geometric mean of gauss, enseignement mathematique, nd ser., ( ). - . g. w. dunnington, gauss: titan of science, with additional material by jeremy gray (maa, ). a. rice. what makes a great teacher? the case of augustus morgan. the american mathematical monthly : ( ), - . c .indd © nature publishing group ~n~a~tu~re~v~o~l~. ~ ~ ~ll~a~u~g~u~s~t~ ~ ~----------------------nevvs--------------------------------------------~~= big is beautiful for survival of higher education in australia sydney forced amalgamations for tertiary institutions with fewer than , students is the most contentious element of new australian government policy on higher education announced at the end of last month by mr john dawkins, minister for education, employment and training. the policy gives effect to most of the reforms suggested last december (see nature , ; ). the central element of the policy is the establishment of a 'unified national general recurrent, equipment, minor works and special research grants. institutions choosing not to join the unified system will be funded for teaching only, receiving nothing for growth or research. institutions with fewer than , students, of whom there are at pres- ent , will not be allowed to join the unified national system. pressure will also be put on institutions with between , and , students to amalgamate. the minimum number of students is , , at which the government believes an institu- tion will be able to deliver a comprehen- sive range of courses as well as being able effectively to involve itself in research in some specialized areas. private institutions such as the bond university will not receive any govern- ment support, nor will their students be eligible for study benefits. staff will, how- ever, be able to compete for research grants from the australian research council (arc). money for research will be transferred from operating grants to the arc in stages, until the arc has an extra a$ million in . the policy statement emphasizes the government's desire to improve manage- ment practices in higher education. dawkins says that it is impossible for some university senates and college councils with up to members to operate effici- ently. he says a more appropriate size would be - , in line with the size of boards in large private organizations. charles morgan uk universities turning more and more to private funding system' for higher education. in order to join, an institution will have to prepare an 'institutional profile' which sets out its objectives and strategy for teaching and research as well as how it is addressing national priorities as defined by the gov- ernment. funding will be based on the institutional profile as well as objective statistical measures of performance com- piled by the government. from , funding for institutions in the unified national system will be a single operating grant which will replace present separate london universities in britain are relying increasingly on private rather than public funding. statistics published this month by the universities statistical record, which detail income and expenditure in - , show that the proportion of university funding from central government grants fell to per cent, compared with per cent and per cent in the previous years and per cent years ago. last year's grant of £ , million was a per cent increase on the previous year. and the total income of universities increased by per cent to almost £ , million. but the underlying trend is an increase in the proportion of university income earned from research contracts and services, a trend that the government is encouraging. last year, the funding generated in this way rose by per cent, almost £ million, to £ million. there was an increase in funding of per cent from charities, of per cent from overseas organizations, of per cent spanish cabinet in science reshuffle barcelona research and university, is considered a in a cabinet reshuffle, mr jose maria personal friend of prime minister felipe maravall has been replaced as spanish gonzalez and a person open to dialogue minister of education and science by mr and negotiation. he takes charge at a time javier solana, former minister of culture, when new action on salaries is expected in who will take over at a delicate time for september at all levels of education, education and science in spain. including the universities, and when criti- maravall, minister of education and cisms are increasing on the way the law of science since the first socialist government universities is working. he will have to in , has been responsible for important continue the efforts to put into practice the reforms in primary and secondary schools, national plan of research, now in its first in universities (the law for university year, and to implement the new statutes of reform) and in science (the law of science the csic (science research council) which and the national plan for research). have to be approved soon. solana, a physicist with experience in pedro puigdomenech from british industry and of per cent from the research councils. income from fees also rose, due largely to the increase in fees charged to overseas students. fee income rose by nine per cent from the previous year, £ million to £ million, the same level as five years ago; since then income from full-time students paying home fees has fallen by almost one-third. universities' expenditure increased by per cent to £ , million, bringing the increase over the past five years to almost one third. last year, per cent of general funds went on salaries and wages, an increase of per cent on the previous year, and of almost one-third over the past five years. the largest rise ( per cent) was for academic-related staff such as admin- istrators and computer staff, compared with per cent for technical staff. over the past five years, student-staff ratios have increased in most depart- ments, particularly in clinical subjects, because reductions in full-time staff have been substantially greater, says the report, than the changes in student numbers. last year there were about , full-time staff and , part-time academic and related staff, a per cent rise over the previous year. that increase was due to an increase of per cent in the number of staff not paid from university funds. those staff now constitute one-third of all full- time academic staff, compared with per cent years ago. there was no increase in the number of full-time teaching and research staff paid from general funds. of staff not paid from general funds, per cent are financed by the research councils, per cent by other government depart- ments and per cent by industry. christine mcgourty big is beautiful for survival of higher education in australia j. fash. bus. vol. , no. : - , sep. issn - (print) http://dx.doi.org/ . /jfb. . . . issn - (online) corresponding author: barng keejung, tel. + - - - , fax. + - - - e-mail: wp @nate.com 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품, 관심도에 따른 뷰티행동 연구 방 기 정 대전대학교 뷰티건강관리학과 조교수 a study on the beauty action of the high-school girl with the beauty, beauty products, and multi-function beauty product interest. barng keejung assistant professor, dept. of beauty health management, daejeon university abstract teenage girls under the influence of the physical changes due to the rapid physical development and appearance are interested. parts were used for the statistical analysis of this research against the common excitation high school student positioned in seoul. first, there was lots of the girl student managing the appearance due to the psychological satisfaction. and the girl student without the friend of the opposite sex managed the appearance at the psychological satisfaction. because to be more important, thing including the studying, and etc. was the priority the girl student who doesn't the appearance management did not do the appearance management. second, the factor found out over one month allowance , circle to be the very important factor through the beauty action high of the high beauty product concern degree and girl student action of the beauty product concern degree and girl student where there is the friend of the opposite sex. third, the more the concern degree about the beauty product was high as the concern degree about the beauty was high, the girl student in high school could know that beauty action was high as the concern degree about the multi function beauty product was high. 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구, key words : 뷰티행동beauty behavior( ), h 여고생 뷰티행igh-school girls beauty behavior( 동 뷰티관심 뷰티제품관심), interest in beauty( ), interest and beauty products( ), 멀티기능 뷰티제품multi-functional beauty products( ) 서 론.Ⅰ 아름다움에 대한 관심은 여성이라면 누구나 소유 하고 있는 것이고 자신의 외모를 아름답게 가꾸기, 위해 여성들은 적극적으로 외모관리를 하고 있다. 여고생은 생물학적 연령기에 해당하며 외모나 이성, 에 대한 호기심이 많아 화장을 직접 경험해 봄으로 써 아름다워지고 싶은 심리적인 욕구를 해결하려고 한다 우리사회는 외모를 중요시하는 문화가 큰 관. 심사로 떠오르고 있으며 신체적 정신적 변화를 지, , 나게 되는 청소년기 학생들에게 외모와 신체 이미지 에 대한 사회적 영향력이 더욱 더 커지고 있다. ) 또 한 여성들의 사회진출 증가로 인한 여성의 사회적, 지위와 역할 기능이 다양화 되면서 패션과 뷰티에, 대한 관심의 증가와 좋은 신체적 외모가 행복과 성 공을 위한 중요한 조건으로 인식되고 있다 여성들. 은 자신의 이미지 변화를 위해 패션과 뷰티의 소비 생활에 깊이 관여하고 있다 이는 외모가 개인의 자. 아존중감 인간관계 행동양식 등에 매우 중요한 영, , 향을 미치기 때문이다. ) 전문적으로 메이크업을 한 모습은 더 매력적이고 여성적이며 섹시하게 지각되, 고 타인에게 좋은 인상을 심어주는 사회생활의 커, 뮤니케이션을 위한 것이라 할 수 있다. 자기만족은 옷차림과 머리모양 메이크업 성형 체중관리 등의, , , 외모관리에 영향을 미치고 더 나아가서는 사회생활 과 자신의 삶을 질적으로 향상시키는데 기여한다. ) 뷰티제품의 구매연령은 중저가 화장품의 보급과 대중매체의 영향으로 점점 낮아지고 있다 사회문화. 적 변화를 통해 청소년들은 중요한 소비주체 잠재, 소비자로 떠오르고 있다 한류와 아이돌에 의한 뷰. 티 트렌드에 민감한 청소년의 모방적 뷰티행동을 통 해 뷰티제품의 관심은 매우 높다 자신의 신체 및. 외모에 가장 관심이 높은 연령대의 청소년기 여고생 은 무시할 수 없는 소비고객이며 향후 화장품을 구, 매할 수 있는 잠재 소비자이기도 하다 유행에 민감. 한 대 여고생들의 화장관심도와 화장행동 및 화장 품 사용실태를 파악한다면 미래의 구매력 있는 소비 자를 위한 마케팅 전략에 도움이 될 것이다. 따라서 본 연구에서는 고등학교 여학생의 뷰티관 심 뷰티제품 및 멀티기능 뷰티제품에 대한 관심과, 뷰티행동에 대해서 알아보고 이러한 관심이 뷰티행 동에 미치는 영향과 뷰티 소비행동에 미치는 영향에 대하여 알아보고자 한다. 여고생의 뷰티관심과 뷰티관련 제품 및 멀티기능 뷰티제품 관심과 뷰티행동의 상관관계를 통해 학문 적 기초자료를 제공하고 관련업계 마케팅 전략수입, 에 대한 방향을 제공하는데 본 연구의 의의가 있다 고 하겠다 본 연구 결과는 유행에 민감한 청소년의. 뷰티행동과 제품관여를 통해 미래의 구매력 있는 소 비자를 위한 마케팅 전략에 도움이 될 것이다. 이론적 배경.Ⅱ 뷰티 관심도 . 뷰티의 사전적 의미는 아름다‘beauty [|bju:ti]’ 움 미 미모 아름다운 것 훌륭한 것으로 시청, , , , (視 을 매개로 얻어지는 기쁨과 아름다움이라는 뜻을)聽 지니고 있다 일반적으로 미용이라는 단어를 대신하. 여 사용되어지고 있으며 사전적 의미는 얼굴이나, ‘ 머리를 아름답게 매만지는 것 으로 정의할 수 있’ 다. ) 그러나 현대사회에서의 뷰티는 좀 더 확장적인 개념으로 받아들여져 종전에는 화장품 산업에만 국, 한 되었던 뷰티산업의 범위가 훨씬 더 광대한 영역 으로 확장되고 있다. ) 우리나라에서 뷰티라는 단어 는 미용을 대신하여 사용되어지고 있으며 미용의, 사전적 의미는 얼굴이나 머리를 아름답게 매만지는‘ 것으로 정의되어 있다’ . 뷰티 관심도란 뷰티와 관심 도의 합성어로‘ ’ ‘ ’, ‘ ’ 뷰티의 미 라는 뜻이 현재 패션 및 뷰티업계와‘ ’ ( )美 사회전반에서 머리와 얼굴 손 발톱 등을 아릅답게, , 패션비즈니스 제 권 호 단장하는 것을 의미하며 이러한 관심 등에 마음을, 두고 주의를 기울이고 가꾸는 것과 이러한 뷰티산업 전반에 대한 관심도를 의미 한다. ) 즉, 사회적 이상 형과 자신의 실제 외모와의 차이를 좁히기 위해 메 이크업 피부 관리 헤어연출 성형수술 체중관리, , , , 등의 수단을 활용하여 외모를 관리하는 행동과 관심 의 정도를 의미한다고 할 수 있다 신체관리를 비롯. 하여 여러 가지 도구 즉 화장품 외모 관련 제품, , 등을 사용하여 관리하는 정도를 의미한다. ) 외모관리는 자신에 대한 시각적 이미지를 만들어 나갈 뿐만 아니라 상황에 맞추어 외모상징의 의미를 전달함으로써 자신을 표현하는 수단이라고 할 수 있 다. 인간의 근본적 욕구인 미적 욕구를 충족시켜줌 과 동시에 자기 자신을 재발견하여 변화된 새로운 모습으로 바꾸어주어 자신의 모습을 더욱 세련되고 매력적인 이미지 개성적인 이미지로 나타낼 수 있, 는 자기표현의 수단이다. ) 화장은 자신의 결점을 커 버하고 자기 자신의 개성을 더욱 돋보이게 하여 한 층 더 자신의 매력을 높이는 행위로 정의된다. ) 외 모를 보완하고 과시적 효과를 증대시킬 수 있으므로 화장은 이러한 커뮤니케이션을 원활하고 효율적으로 행하기 위한 하나의 도구로 과거에는 결점을 커버하 는데 주안점을 두었다면 현재는 오히려 자신의 장점 을 살려 자기표현의 수단으로써 사회가 요구하는 외 모 조건에 좀 더 밀접하게 갈 수 있는 방법 중의 하 나라고 할 수 있다 화장에 관심이 높은 여학생들의. 다수가 높은 가시성과 함께 상황 장소에 따라 다양, 한 변화가 가능한 화장행동으로 외모관리를 한다고 볼 수 있다. 정경숙 서경현의 선행연구에서 뷰티에 대한 관심, 이 외모향상을 위한 관리노력과 뷰티행동으로 이어 지고 그 결과 심리적인 욕구의 충족이 나타난 것 ) 이 라고 하였다 설현진 최인려는 여성청소년은 이. , 성친구가 있으며 연령이 높고 부모의 교육정도가, , 낮으며 용돈이 많을수록 뷰티관심도가 높고 뷰티, , 행동도 적극적이라고 하였으며 외모의 자신감과 얼, 굴 만족도가 높을수록 얼굴 뷰티관심도에 영향을 미 친다고 하였다. ) 김영란의 연구에 의하면 뷰티관리 가 많이 이루어질수록 긍정적인 효과가 많이 나타나 며 화장에 대한 관심이 높을수록 자기 이해가 높아, 져 자신의 개성에 맞는 긍정적 외모를 표현함으로써 자신에 대한 만족감이 커지고 자신감과 심리적 안정 감을 가지게 되어 대인관계가 원활하게 유지된다고, 하였다. ) 심준영 김현희에 의하면, 화장은 자기를 보다 자기답게 나타내 주는 얼굴을 중심으로 행해지 는 의도적 표출법으로 화장에 대한 관심은 맨 얼굴 과 다른 자기를 연출하고 자신감을 얻어 자신을 표, 현하고자 하는 욕구이다. ) 박은정 정명선의 연구에, 의하면 우리나라 대다수의 여성들의 화장 헤어관리, , 마시지나 팩의 사용 기능성 화장품 사용 빈도는 낮, 지만 체중감소를 위한 다이어트 설사제와 구토제, 복용 및 흡연 성형 수술 등 위험이나 고통을 수반, 하는 극단적인 외모관리행동 특성을 보이기도 하며, 자아존중감과 외모관리행동 연구에서 자아존중감이 높을수록 외모관리행동이 높았다. ) 황윤정 조기여, , 유태순의 연구에 의하면 미용성형 보다는 가벼운 메 이크업 등으로 외모관리를 하는 것을 더 선호하는 것으로 나타났다. ) 장선철 송미현은 남녀공학보다, 는 여고생이 외모에 대한 관심이 더 높았고 자아존, 중감이 높은 학생이 외모에 대한 만족도 더 높다고 하였다 또한 외모 만족도와 자아 존중감 및 학교적. 응 간에 정적인 상관이 있으며 청소년의 외모만족, 감 및 학교적응에 매우 중요한 변인으로 나타났 다. ) 뷰티제품 . 뷰티산업은 화장품 다이어트 네일아트 미용문, , , 신 피부 미용관리 등을 통해 신체를 미학적으로 꾸, 미는 것을 목적으로 하는 산업을 말하며 뷰티산업, 의 범위는 외과적 수술을 통하지 않고 몸을 미학적 으로 바꾸어 내는 것이라 볼 수 있으며 인공적인, 과정을 통해 자연 미인을 만드는 과정 전체를 의‘ ’ 미하며 우리 생활 전반에 걸쳐 중요한 자리를 하고 있다. 삼성경제연구소에서는 뷰티산업의 분류를 개의 영역으로 나누어 설명하고 있는데 미관 미담, ( ),美觀 미품 그리고 신체의 외모를 아름답게( ), ( ),美談美品 가꾸는 것과 관련된 산업을 미모 로 분류하고( )美貌 있다 뷰티 제품은 뷰티라는 용어를 머리 얼굴 손. , , , 손톱 등을 가꾸는 의미로 사용함에 있어서 미모에 해당되는 뷰티산업에 뷰티제품을 대상으로 분류하는 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구, 것이 일반적이고 자연스러운 것이다 그래서 본 연. 구에서는 미모 로 분류하는 뷰티산업에 뷰티제( )美貌 품을 대상으로 연구를 진행하고자 한다 뷰티제품은. 사람의 외모를 손질하여 아름답게 꾸미는 물건 제‘ , 품이라고 설명할 수 있다’ . ) 정은주의 연구에 의하면 여고생들은 로션 스킨, , 폼 클린저를 많이 사용하며 선크림 미백의 기능성, , 화장품을 많이 사용하여 깨끗한 피부가 사회적 현상 임을 그대로 받아들였으며 여자 중 고생 기, · . % 초 색조화장품을 사용하고 있었다, % . ) 본 결과를 바탕으로 뷰티제품은 사람의 외모를 손 질하여 아름답게 꾸미는 물건 및 제품으로, 멀티기 능 뷰티제품은 여러 가지의 기능을 가지고 있는 다 기능의 뷰티 제품이라고 설명할 수 있다. 뷰티행동 . 뷰티행동은 자신의 모습을 더욱 세련되고 매력적 인 이미지 개성적인 이미지로 나타낼 수 있는 자기, 표현의 수단이며 복잡하고 다양화되는 사회에서 자 신을 나타내기 위한 하나의 수단이며 도구로 여겨진 다 뷰티행동은 성별 및 연령이 다양하게 나타나고. 있으며 대상자의 연령 또한 많이 낮아지고 있다, . 우리는 의복을 선택하고 화장하는 행동을 포함한 외 모를 가꾸는 행동을 통해 다른 사람들이 우리를 어 떻게 지각하는가에 많은 영향을 받는다. ) 뷰티행동은 인류의 역사와 더불어 시작되었으며, 현대에는 대중매체의 발달과 생활수준의 향상으로 뷰티산업은 뷰티행동이 대중에게 보편화되는 계기를 마련하였다 뷰티행동은 사춘기 여고생들의 집단 간. 의사소통을 위한 도구의 형태로 나타나고 있다 여. 고생들은 중요한 소비주체 잠재적 소비자이며 중, , 저가 화장품 보급과 대중매체로 인해서 연령이 낮아 지고 있다. ) 뷰티행동은 사회문화를 반영하고 의복의 발전과 뷰티산업의 발전과 밀접한 관계를 유지하며 사회 심 리학적인 관점에서 타인과의 상호작용 시 의사전달 수단 ) 및 심리적 장식적 기능을 수행하고 있다, . ) 박수진은 여대생들은 메이크업 시 피부를 보호하는 데 관심이 있고 평소에는 기초화장품을 사용하고, 아이섀도나 립스틱 등 색조화장은 잘 사용하지 않는 다 또한 여대생은 메이크업 유행 트렌드에 따라 민. 감하고 잘 수용한다고 했다. ) 최수경은 화장행동이 신체를 보호하고 아름답게 보이기 위한 장식행동일 뿐만 아니라 사회 심리학적 관점에서 타인과의 상호 작용 시 의사전달의 수단이 되기도 한다. ) 박선희 는 화장행동에 따라 자기 만족형 자기 과시형‘ ’, ‘ ’, 유행 지향형 사회 활동형 가지 심리유형 중 현‘ ’, ‘ ’, 대 여성의 화장행위는 유행 지향형이 가장 많은‘ ’ 분포를 보였으며 개인의 개성보다는 화장품 회사에, 서 제시하는 미용정보나 유행하는 연예인의 화장의 영향을 많이 받는다고 하였다. ) 유창조 정혜은, ) 은 고등학생의 경우 피부 관리 보다는 메이크업을 더 많이 하고 ) , 김은주는 성형수술 시기가 주로 고등 학교 학년에서 대학교 학년 재학 중에 수술부위 , 는 쌍꺼풀, 코 수술이 많고 결과는 대체로 만족한, 다고 하였다. ) 설현진 최인려의 연구에서는, 청소년 의 외모만족 형성에는 가족의 영향을 더 많이 받고 ) 용돈 수준이 높을수록 얼굴뿐만이 아닌 전체적, 인 외모관리에 더 적극적이라고 하였다. ) 이상의 내용에서 여고생의 뷰티행동에는 뷰티 뷰, 티제품 멀티기능 뷰티제품 관심 외모관리 유 무 등, , · 이 영향력 있는 변인임을 알 수 있으며 여고생의, 뷰티행동은 또래집단 관계에 영향력 있는 변인임을 알 수 있다 그러므로 본 연구에서는. 자신의 신체 및 외모에 가장 관심이 높은 여고생을 대상으로 뷰 티 및 뷰티제품 멀티기능 뷰티제품 관심도의 요인, 들을 기준으로 뷰티행동과의 상관관계를 알아보고자 한다. 연구 방법.Ⅲ 연구문제 . 여고생의 뷰티행동은 뷰티관심도와 유의미한 ) 상관관계가 있는가? 여고생의 뷰티행동은 뷰티제품 관심도와 유의 ) 미한 상관관계가 있는가? 여고생의 뷰티행동은 멀티기능 뷰티제품 관심 ) 도와 유의미한 상관관계가 있는가? 패션비즈니스 제 권 호 연구대상 및 자료수집 . 본 연구의 분석단위는 개인이며 서울에 위치하고, 있는 고등학교 여학생을 대상으로 비확률 표본추출 방법인 편의추출을 실시하였다 설문기간은. 년 월 일부터 월 일까지 시행하였으며 설문지를, 사용한 조사 연구법이었다 설문지는 뷰티행동 뷰. , 티관심 뷰티제품 관심 및 멀티기능 제품 관심 변인, 의 내용으로 구성되었다. 설문지 배부는 연구자가 담임선생님을 대상으로 설문조사에 대해 간단히 설 명한 후 설문지를 배포하였고 작성된 설문지는 응, 답한 후 즉시 회수 하였다 설문조사 결과 총 부. 를 배포하여 부가 회수되었으며 회수된 자료 중 불완전하거나 불충분하게 작성된 부를 제외한 총 부가 본 연구의 통계분석을 위하여 사용되었다 . 측정도구 . 본 연구에서 사용된 조사도구는 설문지를 사용하 였으며 측정도구의 구성은 아래 표 과 같다 총, < > . 부로 구성되었으며 부는 인구통계적 특성에 관한 , 문항으로 만들어졌으며 부는 뷰티관심 관련된 문, 항으로 부는 뷰티제품 관련된 문항으로 부는 뷰, , 티행동 관련 문항으로 작성하여 조사하였다 구성내. 용은 인구통계적 특성 문항 뷰티관심도 문항( ), ( ), 뷰티제품 관심도 문항 멀티기능 뷰티제품 관심도( ), 문항 뷰티행동 문항 의 개의 영역으로 구성하( ), ( ) 였으며 뷰티 및 뷰티제품 관심도 멀티기능 뷰티제, , 품 관심도 뷰티행동 개 영역의 각 문항은 전혀, ‘ 그렇지 않다 점 에서 매우 그렇다 점 의 점’( ) ‘ ’( ) 척도로 구성되었다likert . measuring tools configuration number measured variables number of questions how to measure part i demographic characteristics multiple choice / technology type part ii interest in beauty multiple choice / steps how to likert part iii beauty product step likert method part iv beauty behavior step likert method 인구 통계적 특성 ) 인구 통계적 변인은 학년별 거주지별 한 달 용, , 돈별 이성친구 유무를 조사하였다 일반적으로 여, . 고생의 학년별 한 달 용돈과 이성친구의 유무는 뷰, 티행동과 뷰티제품과 관계가 있으며 뷰티제품과 멀, 티기능 뷰티제품에 대한 관여 등에 영향을 줄 수 있 을 것으로 판단되어 선정하게 되었다. 뷰티관심도 및 외모관리행동 ) 뷰티관심도와 외모관리행동은 패션 및 뷰티업계와 사회전반에서 머리와 얼굴 손 발톱 등을 아름답게, , 단장하는 것을 의미하고 이러한 행위 등에 마음을, 두고 주의를 기울이고 가꾸는 것과 이러한 뷰티산업 전반에 대한 관심도를 의미한다 뷰티관심도를. 측정 하기 위하여 사용된 문항은 선행연구 ) ) ) 의 내용 을 토대로 연구자가 본 연구의 대상자에 맞게 수정, 보완하였으며 최종 문항으로 구성되었다, . 이 문 항에 대하여 신뢰도 검사결과 문항의 신뢰도는 였다. . 측정방법은 점 형 척도를 사용하였 likert 으며 점수가 높을수록 뷰티관심이 더 많은 것을 의, 미한다. 뷰티제품 및 멀티기능 뷰티제품 관심도 ) 뷰티제품은 사람의 외모를 손질하여 아름답게 꾸 미는 물건 및 제품을 뜻하며 멀티기능 뷰티제품은, 여러 가지의 기능을 가지고 있는 다기능의 뷰티제품 을 의미한다 본 연구의 연구대상인 여고생을 고려. 하여 인구통계학적 범위를 학년별 용돈별 이성친, , , 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구, 구 유무별로 분류하였다 뷰티제품 및 멀티기능 뷰. 티제품의 관심을 측정하기 위해 사용된 문항은 선행 연구의 내용을 참고로 하여 연구자가 수정 보완하였 으며 뷰티제품 문항 멀티기능 뷰티제품 문항으, , 로 구성되었다 뷰티제품 관심. 문항에 대하여 신뢰 도 검사결과는 멀티기능 뷰티제품 관심에 대한. , 문항의 신뢰도는 이였다 . . 측정방법은 점 likert 형 척도를 사용하였으며 점수가 높을수록 뷰티제품, 및 멀티기능 뷰티제품에 대한 관심이 더 많은 것을 의미한다. 뷰티행동 ) 뷰티행동은 자신의 모습을 더욱 세련되고 매력적 인 이미지 개성적인 이미지로 나타낼 수 있는 자기, 표현의 수단이며 도구이다. 뷰티행동 측정도구는 외 모관리 중 뷰티행동에 관한 문항으로 이루어졌다. 뷰티행동과 관련된 선행연구 ) ) 그리고 외모관리에 대한 선행연구 ) ) 를 기초로 하여 전문가 집단과 토 의하여 연구목적에 맞게 수정 보완하여 작성하였다, . 뷰티행동을 측정하기 위해 사용된 문항은 선행연구 ) 에서 본 연구 대상자에 부합하는 문항을 선택하 였다 이 문항에 대하여 신뢰도 검사결과 문항의. 신뢰도는 였다 측정방법은 점 형 척도를. . likert 사용하였으며 점수가 높을수록 뷰티행동이 더 높다, 는 것을 의미하였다 본 연구 측정도구의 신뢰도를. 검증한 결과는 아래 표 와 같다< > . 분석방법 . 본 연구의 수집된 자료는 spss(statistical package
the reliability of the measurement tool division number of questions alpha interest in beauty . the interest of beauty products . beauty behavior . the interest of multi-function beauty products . 프로그램을 이용for the social science) win . 하여 분석하였다 분석기법으로는 연구대상자의 일. 반적 특성을 파악하기 위해 빈도와 백분율을 산출하 였으며 고등학교 여학생들의 뷰티관심도와 뷰티제, 품의 관심도 뷰티행동 그리고 멀티기능 뷰티제품, , 의 관심도를 알아보기 위해 χ 검증과(chi-square) 검증 그리고 일원변량분t-test( ), one-way anova( 석 을 실시하였다 또한 고등학교 여학생들의 뷰티) . 관심도 및 뷰티제품의 관심도 그리고 멀티기능 뷰, 티제품의 관심도와 뷰티행동과의 관계를 살펴보기 위해 상관관계분석 을 실행하여 변수들correlation( ) 의 영향관계를 검증하였다. 결과 및 논의.Ⅳ 연구대상 . 연구대상자의 일반적 특성은 아래 표 과 같다< > . 본 연구결과 명의 응답자들의 인구통계적 특성 을 살펴보면, 학년별로는 학년이 로 가장 많 . % 았으며 다음으로 학년 학년 순으, . %, . % 로 나타났다 거주지별로는 서울지역이 로 대. . % 부분을 차지하였다 한 달 용돈별로는 만원 미. ～ 만이 로 가장 높은 분포를 보였으며 다음으 . % , 로 만원 미만 기타 만원 이상 . %, . %, 만원 미만 순으로 차지하였다 . %. . % .～ 이성친구 유무별로는 단순한 친구가 있는 학생이 로 가장 많았으며 다음으로 없다 있 . % , . %, 다 순으로 나타났다 . % . 패션비즈니스 제 권 호
general characteristics of study subjects division rate (people) percent (%) grade first grade . grade . grade . living seoul . gyeonggi . monthly allowance less than , ₩ . less than to , won . less than to , won . less than to , won . more than , won . etc. . male friends have . is just a friend . not . total . 뷰티 및 뷰티제품 관심도 . 뷰티 관심도 ) 고등학교 여학생들의 뷰티에 대한 관심은 표< > 와 같이 점 만점 중 전체 평균이 으로 뷰티에 . , 대한 관심이 그다지 높지 않은 것으로 나타났다 학. 년별로는 학년 여학생이 뷰티에 대한 관심도가 가 장 높았고 학년 여학생은 다른 여학생보다 뷰티에, 대한 관심도가 낮았다. 한 달 용돈별로는 만원 이상 여학생이 뷰티제품 에 대한 관심도가 가장 높았고 기타인 여학생은 다, 른 여학생보다 뷰티제품에 대한 관심도가 낮았으며, 한 달 용돈에 따라 유의미한 차이를 보였다(f= . , 이성친구 유무별로는 이성친구가 있는 여학p<. ). 생이 그렇지 않은 여학생보다 뷰티에 대한 관심도가 높았으며 이성친구 유무에 따라 유의미한 차이를, 보였다(t= . , p<. ). 이상과 같이 고등학교 여학생들은 뷰티에 대한 관 심도가 그다지 높지 않았으며 이성친구가 있는 여, 학생이 뷰티에 대한 관심도가 높았다 즉 고등학교. 여학생의 경우 이성친구가 있으며 만원 이상의 용, 돈별 구분에 따라 학년이 고학년일 경우 뷰티에 대, 한 관심이 높다고 볼 수 있으며 더욱 높은 관여를, 한다 그러므로 학년별 용돈별 이성 친구 유무의. , , 요인은 뷰티관심에 영향을 미치는 요인이라고 해석 할 수 있다 이러한 결과는 선행연구 설현진 최인. , 려와 정경숙 서경현 그리고 장선철 송미현, , ) 의 연 구결과와 유사한 결과로 사회적인 환경변화에 따라 고등학교 여학생들의 뷰티관심에 높은 관여 요인으 로 청소년기에 이성친구와 학년이 올라갈수록 그리 고 용돈에 따라서 다각도로 나타나고 있음을 알 수 있었다. 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구,
interest in beauty division n mean sd t(f) p grade first grade . . . . grade . . grade . . monthly allowance less than , ₩ . . . * . less than to , won . . more than , won . . etc. . . have male friends have . . . * . not . . totality . . * p<.
the interest of beauty products division n mean sd t(f) p grade first grade . . . . grade . . grade . . monthly allowance less than , ₩ . . . * . less than to , won . . more than , won . . etc. . . have male friends have . . . . not . . totality . . * p<. 뷰티제품 관심도 ) 고등학교 여학생들의 뷰티제품에 대한 관심도에 대해 살펴본 결과는 표 와 같이 점 만점 중 전< > 체 평균이 로 고등학교 여학생들은 뷰티제품에 . , 대한 관심도가 그다지 높지 않은 것으로 나타났다. 학년별로는 학년 여학생이 뷰티제품에 대한 관심 도가 가장 높았고 학년 여학생은 다른 여학생보다, 뷰티제품에 대한 관심도가 낮았으나 통계적으로는 패션비즈니스 제 권 호 유의미한 차이를 보이지 않았다 한 달 용돈별로는. 만원 이상 여학생이 뷰티제품에 대한 관심도가 가 장 높았고 기타 여학생은 다른 여학생보다 뷰티제, 품에 대한 관심도가 낮았으며 한 달 용돈에 따라, 유의미한 차이를 보였다 이성친구(f= . , p<. ). 유무별로는 이성친구가 있는 여학생이 그렇지 않은 여학생보다 뷰티제품에 대한 관심도가 높았으나 유 의미한 차이는 아니었다. 이상과 같이 고등학교 여학생들은 뷰티제품에 대 한 관심도가 그다지 높지 않았으며 한 달 용돈이, 만원 이상 여학생이 다른 여학생보다 뷰티제품에 대 한 관심도가 높았다. 이상과 같이 고등학교 여학생 들은 뷰티에 대한 관심도가 그다지 높지 않았으며, 한 달 용돈이 만원 이상 여학생이 뷰티제품 에 대한 관심이 높았다 즉 고등학교 여학생의 경우 만원. 이상 용돈별 구분에 따라 뷰티 제품에 대한 관심이, 높다고 볼 수 있으며 더욱 높은 관여를 한다 그러, . 므로 용돈별 금액에 따른 요인은 뷰티제품 관심도에 영향을 미치는 요인이라고 해석할 수 있다 이러한. 결과는 선행연구 설현진 최인려와 정은주의 연구결, 과와 유사한 결과로 멀티미디어의 발달과 모방심리, 가 강한 청소년에게 사회적인 환경변화에 따라 고등 학교 여학생들의 용돈에 따른 요인은 뷰티제품에 대 한 높은 관여요인으로 나타나고 있음을 알 수 있었다.
the interest of multi-function beauty products division n mean sd t(f) p grade first grade . . . . grade . . grade . . monthly allowance less than , ₩ . . . . less than to , won . . more than , won . . etc. . . have male friends have . . . . not . . totality . . 멀티기능 뷰티제품 관심도 ) 고등학교 여학생들의 멀티기능 뷰티제품에 대한 관심도에 대해 살펴본 결과는 표 과 같이 점< > 만점 중 전체 평균이 로 고등학교 여학생들은 . , 멀티기능 뷰티제품에 대한 관심도가 그다지 높지 않 은 것으로 나타났다. 학년별로는 학년 여학생이 멀티기능 뷰티제품에 대한 관심도가 가장 높았고 학년 여학생은 다른, 여학생보다 멀티기능 뷰티제품에 대한 관심도가 낮 았으나 통계적으로는 유의미한 차이를 보이지 않았 다 한 달 용돈별로는 만원 이상인 여학생이 멀티. 기능 뷰티제품에 대한 관심도가 가장 높았고 기타, 인 여학생은 다른 여학생보다 멀티기능 뷰티제품에 대한 관심도가 낮았으나 유의미한 차이는 없었다. 이성친구 유무별로는 이성친구가 있는 여학생이 그 렇지 않은 여학생보다 멀티기능 뷰티제품에 대한 관 심도가 높았으나 이성친구 유무에 따른 유의미한 차 이는 없었다. 이상과 같이 고등학교 여학생들은 멀티기능 뷰티 제품에 대한 관심도가 그다지 높지 않았으며 학년, 과 한 달 용돈 그리고 이성친구 유무별로는 별다른, 차이를 보이지 않았다 이러한 결과는 선행연구. 박 은정 정명선, 의 기능성 화장품의 사용빈도가 낮다는 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구, 연구결과와 유사한 결과로 멀티미디어의 발달에 따, 른 사회문화적 배경과는 다르게 멀티기능 뷰티제품 에 대한 낮은 관여를 나타나고 있음을 알 수 있었 다. 뷰티행동 . 뷰티행동 ) 고등학교 여학생들의 뷰티행동에 대해 살펴본 결 과는 표 과 같이 점 만점 중 전체 평균이< > . 로 고등학교 여학생들은 뷰티행동이 그다지 높지, 않은 것으로 나타났다. 학년별로는 학년 여학생이 뷰티행동이 가장 높았 고 학년 여학생은 다른 여학생보다 뷰티행동이 낮, 았으나 유의미한 차이는 없었다 한 달 용돈별로는. 만원 이상 여학생이 뷰티행동이 가장 높았고 기타 , 여학생은 다른 여학생보다 뷰티행동이 낮았으나 한 달 용돈에 따른 유의미한 차이는 없었다 이성친구. 유무별로는 이성친구가 있는 여학생이 그렇지 않은 여학생보다 뷰티행동이 높았으며 이성친구 유무에, 따라 유의미한 차이를 보였다(t= . , p<. ). 이상과 같이 고등학교 여학생들은 뷰티행동이 그
beauty behavior division n mean sd t(f) p grade first grade . . . . grade . . grade . . monthly allowance less than , ₩ . . . . less than to , won . . more than , won . . etc. . . have male friends have . . . *** . not . . totality . . ** p<. 다지 높지 않았으며 이성친구가 있는 여학생이 그, 렇지 않은 여학생보다 뷰티행동이 높았다 즉 고등. 학교 여학생의 경우 이성친구가 있는 경우가 뷰티행 동이 높다고 볼 수 있으며 이성친구 유무의 요인은, 뷰티행동에 영향을 미치는 요인이라고 해석할 수 있 다 이러한 결과는 선행연구 최수경과 설현진 최인. , , 려 그리고 장선철 송미현의 연구결과를 지지하였다, . 외모관리 이유 ) 고등학교 여학생들이 외모관리를 하는 이유에 대 해 살펴본 결과는 표 과 같이 심리적 만족감 때< > 문에 외모관리를 하는 여학생이 로 가장 많았 . % 으며 기타 원래 스타일에 관심이 많아서, . %, 이성 친구에게 호감을 주기 위해서 . %, . %, 친구사이 관계가 유리해서 순으로 나타났다 . % . 학년별로는 학년 여학생과 학년 여학생이 학 년 여학생보다 심리적 만족감 때문에 외모관리를 하 였고 학년이 높은 여성일수록 원래 스타일에 관심, 이 많아서 외모관리를 하였으나 학년에 따른 유의미 한 차이는 없었다 한 달 용돈별로는 만원 이상 여. 학생이 다른 여학생보다 심리적 만족감 때문에 외모 관리를 하였고 기타 여학생은 다른 여성보다 원래, 패션비즈니스 제 권 호
appearance management reasons division psycholog ical satisfactio n (confiden ce) relationsh ip between friends is easy reason to give good feelings to a friend a lot of interest in the original style etc. total χ (df) p grade first grade ( . ) - - ( . ) ( . ) ( . ) . ( ) . grade ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) grade ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) monthly allowance less than ₩ , ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) . ( ) . less than to , won ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) more than , won ( . ) - ( . ) ( . ) ( . ) ( . ) etc. ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) have male friends have ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) . * ( ) . not ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) totality ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) * p<. 스타일에 관심이 많아서 외모관리를 하였으나 통계 적으로는 유의미한 차이는 없었다 이성친구 유무별. 로는 이성친구가 있는 여학생이 그렇지 않은 여학생 보다 원래 스타일에 관심이 많아서 외모관리를 하였 고 이성친구가 없는 여학생은 있는 여학생보다 심, 리적 만족감 때문에 외모관리를 하였으며 이성친구, 유무에 따라 유의미한 차이를 보였다( = . ,χ p<. ). 이상과 같이 심리적 만족감 때문에 외모를 관리하 는 여학생이 가장 많았으며 이성친구가 없는 여학, 생이 이성친구가 있는 여학생보다 심리적 만족감 때 문에 외모를 관리하였다 즉 고등학교 여학생의 경. 우 심리적 만족감 때문에 외모를 관리하고 이성친, 구가 없는 여학생이 심리적 만족감 때문에 외모를 관리하였다 그러므로 이성친구 유무와 심리적 만족. 감 요인이 외모관리행동에 영향을 미치는 요인이라 고 해석할 수 있다 이러한 결과는 정경숙 서경현. , 과 김영란의 연구 심준영 김현희 그리고, 장선철, 송미현의 연구 최수경 및 김은주의 연구결과와 유, 사한 결과로 멀티미디어의 발달과 모방심리가 강한, 고등학교 여학생들의 이성친구의 유무와 심리적인 만족감 요인은 외모관리 행동에 대한 높은 관여요인 으로 나타나고 있음을 알 수 있었다. 외모관리를 하지 않는 이유 ) 고등학교 여학생들이 외모관리를 하지 않는 이유 에 대해 살펴본 결과는 표 와 같이 공부 등 더< > 중요한 것이 우선이기 때문에 외모관리를 하지 않는 여학생이 로 가장 많았으며 다음으로 관심이 . % , 없어서 기타 시간이 없어서 . %, . %, . %, 경제적 부담으로 학생이 해서는 안 된다고 . %, 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구,
why does not the appearance management division the important thing first (studying, etc.) appearan ce is not important do not have time the economic burden lack of interest i think students should not be etc. total χ (df) p grade first grade ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) . ( ) . grade ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) grade ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) monthly allowan ce less than , ₩ ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) . ( ) . less than to , won ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) more than , won ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) etc. ( . ) ( . ) - ( . ) ( . ) ( . ) ( . ) ( . ) have male friends have ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) . ( ) . not ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) totality ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) 생각해서 외모는 중요한 것이 아니어서 . %, . % 순으로 나타났다. 학년별로는 학년이 높은 여학생일수록 공부 등 더 중요한 것이 우선이기 때문에 외모관리를 하지 않았 고 학년 여학생은 다른 학년보다 관심이 없어서, 외모관리를 하지 않았으나 통계적으로는 유의미한 차이는 없었다 한 달 용돈별로는 만원 미만인 여. 학생이 다른 여학생보다 시간이 없어서 외모관리를 하지 않았고 만원 미만인 여학생은 다른 여학, ～ 생보다 관심이 없어서 외모관리를 하지 않았으나 한 달 용돈에 따른 유의미한 차이는 없었다 이성친구. 유무별로는 이성친구가 있는 여학생이 그렇지 않은 여학생보다 시간이 없어서 외모관리를 하지 않았고, 이성친구가 없는 여학생은 있는 여학생보다 관심이 없어서 외모관리를 하지 않았으나 유의미한 차이는 없었다. 이상과 같이 공부 등 더 중요한 것이 우선이기 때 문에 외모관리를 하지 않는 여학생이 가장 많았으 며 학년과 한 달 용돈 그리고 이성친구 유무별로, , 는 별다른 차이를 보이지 않았다 이상과 같이 공부. 등 더 중요한 것이 우선이기 때문에 외모를 관리하 지 않았다 즉 고등학교 여학생의 경우 공부 등 더. 중요한 것이 우선인 요인이 외모관리행동에 영향을 미치는 요인이라고 해석할 수 있다. 패션비즈니스 제 권 호 뷰티 및 뷰티제품 관심도와 뷰티행동과의 . 관계 변수들 간의 영향관계를 알아보기 위해 상관관계 분석을 하였다. 뷰티 관심도와 뷰티행동과의 관계 ) 고등학교 여학생들의 뷰티에 대한 관심도와 뷰티 행동과의 관계에 대해 살펴본 결과는 표 과 같< > 다 뷰티에 대한 관심도는 뷰티행동. (r=. , 과 통계적으로 유의미한 정 적 상관관계를p<. ) (+) 보였다 따라서 고등학교 여학생들은 뷰티에 대한. 관심도가 높을수록 뷰티행동이 높음을 알 수 있다. 즉 여고생의 경우 뷰티에 대한 관심도가 높을수록 뷰티행동이 높다고 볼 수 있었다 이러한 결과는 일. 반적으로 뷰티관심도와 관련이 높으며 여고생은 뷰, 티관심과 행동에 더욱 높은 관여를 한다 그러므로. 뷰티행동은 뷰티관심의 반영이라고 해석할 수 있다. 뷰티제품 관심도와 뷰티행동과의 관계 )
interesting relationship between beauty and beauty behavior division beauty behavior interest in beauty . *** ( . ) *** p<.
interest in beauty products, behavior and relationships and beauty division beauty behavior interest in beauty products . *** ( . ) *** p<.
multi-function beauty products beauty behavior and the relationship between interest division beauty behavior interest in multi-function beauty products . *** ( . ) *** p<. 고등학교 여학생들의 뷰티제품에 대한 관심도와 뷰티행동과의 관계에 대해 살펴본 결과는 표< > 과 같다. 뷰티제품에 대한 관심도는 뷰티행동 과 통계적으로 유의미한 정 적(r=. , p<. ) (+) 상관관계를 보여 여학생들은 뷰티제품에 대한 관심 도가 높을수록 뷰티행동이 높음을 알 수 있다. 멀티기능 뷰티제품 관심도와 뷰티행동과의 ) 관계 고등학교 여학생들의 멀티기능 뷰티제품에 대한 관심도와 뷰티행동과의 관계에 대해 살펴본 결과는 표 와< > 같다 멀티기능 뷰티제품에 대한 관심도. 는 뷰티행동 과 통계적으로 유의미(r=. , p<. ) 한 정 적 상관관계를 보였으며 여학생들은 멀티(+) , 기능 뷰티제품에 대한 관심도가 높을수록 뷰티행동 이 높음을 알 수 있다. 뷰티에 대한 관심도는 뷰티행동(r=. , p<. ) 과 통계적으로 유의미한 정 적 상관관계를 보였(+) 다 따라서 고등학교 여학생들은 뷰티에 대한 관심. 방기정 / 여고생의 뷰티관심도 뷰티제품 및 멀티기능 뷰티제품 관심도에 따른 뷰티행동 연구, 도가 높을수록 뷰티행동이 높음을 알 수 있다 뷰티. 제품에 대한 관심도는 뷰티행동 과(r=. , p<. ) 통계적으로 유의미한 정 적 상관관계를 보여 여학(+) 생들은 뷰티제품에 대한 관심도가 높을수록 뷰티행 동이 높음을 알 수 있다 멀티기능 뷰티제품에 대한. 관심도는 뷰티행동 과 통계적으로(r=. , p<. ) 유의미한 정 적 상관관계를 보였으며 여학생들은(+) , 멀티기능 뷰티제품에 대한 관심도가 높을수록 뷰티 행동이 높음을 알 수 있다. 본 연구에서는 고등학교 여학생을 대상으로 뷰티 관심도 및 뷰티제품 관심도 멀티기능 제품관심도가, 뷰티행동과 상관관계가 있으며 유의미한 영향을 미, 치는 매우 중요한 요인임을 확인하였다. 결 론.Ⅴ 본 연구는 자신의 신체 및 외모에 가장 관심이 높 은 고등학교 여학생을 대상으로 뷰티 및 뷰티제품 관심도 멀티기능 뷰티제품 관심도의 요인들을 기준, 으로 뷰티행동과의 상관관계를 알아보는 것을 목적 으로 하였으며 본 연구의 결과를 요약하면 다음과, 같다. 첫째 고등학교 여학생은 심리적 만족감 때문에, 외모를 관리하는 여학생이 많았으며 이성친구가 없, 는 여학생은 심리적 만족감에 외모를 관리하였다. 외모관리를 하지 않는 여학생은 공부 등 더 중요한 것이 우선이기 때문에 외모관리를 하지 않았다 둘. 째 고등학교 여학생은 뷰티 및 뷰티제품 관심도, , 멀티기능 뷰티제품에 대한 관심도와 뷰티행동이 그 다지 높지 않았으며 한 달 용돈이 만원 이상의 여, 학생이 뷰티제품에 대한 관심도가 높았고 이성친구 가 있는 여학생 뷰티행동이 높았다 이러한 결과로. 한 달 용돈 만원 이상 요인은 높은 뷰티제품 관심 도와 이성친구가 있는 여학생의 높은 뷰티행동을 통 해 매우 중요한 변인요인임을 알게 되었다 셋째. , 고등학교 여학생은 뷰티에 대한 관심도가 높을수록 뷰티제품에 대한 관심도가 높을수록 멀티기능 뷰티, 제품에 대한 관심도가 높을수록 뷰티행동이 높음을 알 수 있었다. 이상에서 볼 때 고등학교 여학생들은 대중매체의 영향으로 유행에 민감한 세대가 되며 새로운 유행의 선두주자가 되기도 한다 그래서 고등학교 여학생들. 은 뷰티 및 뷰티제품 멀티기능제품에 관심이 많은, 고등학교 여학생 일수록 뷰티행동이 높음을 알 수 있었다. 뷰티행동과 이러한 관심도는 심리적인 요인 과 한 달 용돈의 금액에 따른 요인 이성친구의 유, 무에 따라 높은 관여를 한다고 해석할 수 있다 고. 등학교 여학생들의 뷰티관심에 높은 관여요인으로 만원이 넘는 명품화장품 구입을 하고 또래들 사 , 이에 학교서열이 정해진다고 하는데 이는, ‘신 등( )新 골브레이커라는 유행신조어 등을 탄생시키며 모방‘ , 심리가 강한 청소년의 무분별한 소비행동을 부추기 고 있다. 그러므로 관련 뷰티산업의 발전방향과 추 후 후속연구를 하는데 이러한 고등학교 여학생들의, 뷰티행동에 높은 관여요인들을 참고하여야 할 것이 다. 본 연구를 통해 고등학교 여학생의 멀티기능 뷰 티제품 관심을 통한 뷰티행동의 상관관계를 통해 학 문적 기초자료를 제공하고 마케팅 전략수립에 대한 방향을 제시할 수 있을 것으로 기대한다. 연구의 한계점은 지역적 한계로 객관화하기에는 무리가 있으며 뷰티제품에서도 헤어 메이크업 피, , , 부 네일 두피관리 등을 유형별 세분화와 상표충성, , , 도 브랜드 인지도 등 다양한 변수들과의 연구가 진, 행되어야 할 것이다. 또한 뷰티행동과 뷰티제품과의 측정도구가 제한된 문항으로 조사되어 일반화시키는 데 한계가 있다고 본다. 따라서 조사대상 지역을 확 대하여 특성을 폭넓고 다각적으로 연구할 필요성이 있으며, 뷰티행동과 뷰티제품과의 측정문항을 보다 더 구체화시켜 각 차원과의 관계를 조사할 필요가 있다. 더불어 청소년들의 뷰티행동에 영향을 줄 수 있는 목적과 특성에 따른 문제점을 보다 폭넓게 파 악하는 것이 필요하며 뷰티행동으로 이어지는 문제, 점을 비교 연구하는 것이 필요하다고 본다. reference ) jeong heajung, kim hayeun, lee yuri ( ), “young people interested in 패션비즈니스 제 권 호 self-expression and appearance according to the uniform product purchasing behavior”, the journal of korea society of clothing and textiles, ( ), pp. - 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. ) sual heunjin, choi inryeo( ), “junior high school girls beauty of youth behavior”, the research journal of the costume culture, ( ), pp. - . ) lbid. ) kim youngran( ), op.cit., p. . ) jung gyeongsuk, soe gyeonghyeon( ), op.cit., pp. - . ) sual heunjin, choi inryeo( ), op.cit., pp. - . ) ahan hyeongyeong( ), “a study on the hair style production : focussed on face contour & hair fashion feeling of the capital area women in their twenties”, journal of fashion business, ( ), pp. - . ) han dongjeo( ), “ethno graphic analysis of male high school students’ appearance management activities : fashion, makeup, body management, hair, skin care and cosmetic surgery”, unpublished master dissertation, chungnam university, p. . ) hwang yunjung, joe keyue, yoo teasun( ), op.cit., pp. - . ) sual heunjin, choi inryeo( ), op.cit., pp. - . ) jang sunchal, song mihyeon( ), op.cit., pp. - . 접수일 년 월 일( ) 수정일 년 월 일( ) 게재확정일 년 월 일( ) donor lymphocyte infusion: beauty is in the eye of the beholder m.r. bishop / biol blood marrow transplant ( ) e donor lymphocyte infusion: beauty is in the eye of the beholder michael r. bishop* section of hematology/oncology, university of chicago, chicago, illinois article history: received april accepted april in this issue of biology of blood and marrow trans- plantation, bar et al. report on a retrospective analysis of the effect of cd þ cell dose in initial donor lymphocyte infusion (dli) on graft-versus-host disease (gvhd) and overall sur- vival in patients who received dli for relapsed hema- tologic malignancy, primarily at the fred hutchison cancer research center [ ]. this article is important from several perspectives, on which i will expound. however, the state- ment that i enjoyed the most, and the primary focus of my commentary, is in the first sentence of the discussion: “dli is an attractive salvage treatment option for patients with persistent or relapsed hematologic malignancies.” attrac- tive? now, this may be the first time i have heard of dli being described as attractive. i am sure that i will hear from someone with far too much time on his or her hands of other examples of this adjective to describe dli, but it did make me take pause. based on our overall clinical experience with dli, "attractive" is probably one of the last words i personally would use to describe it. i look at dli more like having to take your best friend to the prom because neither of you has a date, and neither wants to go to the dance alone. out of all the other options, what do you do? beauty is a very relative and subjective term, and maybe it really is in the eye of the beholder. the report by bar et al. provides wonderful background for placing the “beauty” of dli into perspective, reading like a review of the history of dli over the past years. i would actually argue that that this report should be required reading for fellows during their transplantation rotation and an excellent journal club article. it starts out with the obligatory statement that “allogeneic hematopoietic cell transplantation has the potential to provide long-term survival and even cure in patients with hematologic malig- nancies,” which is tough to argue considering that i have started approximately one-half of my own publications with the same statement. this is followed by a statement of who reported the first dli, which is where it really starts to get interesting, given that even this little -patient report has been a repeated point of contention over the years [ , ]. the article then moves on with the “patients and methods” section to describe the patients with a broad variety of hematologic malignancies who were treated over an -year financial disclosure: see acknowledgments on page . * correspondence and reprint requests: michael r. bishop, md, section of hematology/oncology, university of chicago, south maryland ave, mc , chicago, il . e-mail address: mbishop@medicine.bsd.uchicago.edu. - /$ e see front matter � american society for blood and marrow transplantation. http://dx.doi.org/ . /j.bbmt. . . period, and then to how specifically dli was used: with and without chemotherapy or radiation, with adjuvant cytokines (eg, ifn, il- ), use of steady-state or “mobilized” dli, chimerism status and presence or absence of gvhd at the time of dli, and the use of immunosuppression to prevent gvhd. sound familiar? this is not a criticismdthese are extremely relevant biologic and clinical issues that investigators have attempted to address over the past years [ - ]. the authors are self-depreciating when describing the heterogeneity of their patient populations and treatment approaches as a limitation of their study. however, i look at this heterogeneity as a strength, placing the use of dli in a compact historical framework by a group of investigators who have been at the forefront of translational and clinical transplantation research since its inception. possibly the most informative (and somewhat comforting) aspect of this report is that the authors’ results are very similar to what has been previously reported and to general perceptions in the transplantation community [ , ]. consistent with previous observations, bar et al. found that cd þ dose was correlated with the risk of gvhd, and that higher cd þ doses did not decrease the risk of recurrence after successful dli or improve overall survival. at the same time, the results are very disappointing relative to the lack of progress in dli over the last years. the disease for which dli has the best results, chronic myelogenous leukemia, is today a relatively rare indication for transplantation. we are still unsure as to exactly when, how often, how much, precisely what, and with what we should use dli. relative to when, there are no established methods or guidelines for monitoring for disease recurrence after transplantation, with the possible exception of chronic myelogeous leukemia. bar et al. addressed dli dose, but the optimal starting dose, whether the doses should be escalated, and if so, how often remain unclear. maybe we should be giving relatively small (< � cd þ cells/kg) on a more frequent (weekly?) basis. other, possibly even more important questions involve product content and the need for cytoreduction to achieve a minimal residual disease state and immunodepletion for creation of immu- nologic “space” [ ]. the correlation of success of dli with minimal residual disease is well established, and it is difficult to expect dli to be successful in the context of competing for homeostatic and stimulatory cytokines in a immunologically competent host with potentially inhibitory features (eg, t regulatory cells). relative to content, should they specifi- cally be just cd þ cells or subsets, natural killer cells, or some combination? finally, should we just accept it as fact that no matter what we attempt, the results with dli will end up being the same? it is my strong belief this is the not case; many of these questions have been only partially addressed in an adequate manner, and there are several new modalities, such as chi- meric antigen receptors, that may enhance the efficacy of dli and merit further investigation in the allogeneic http://dx.doi.org/ . /j.bbmt. . . http://dx.doi.org/ . /j.bbmt. . . mailto:mbishop@medicine.bsd.uchicago.edu m.r. bishop / biol blood marrow transplant ( ) e transplantation setting [ , ]. the key element is the design and implementation of such studies in multi-institutional settings, which was one the major recommendations from the national cancer institute’s first international workshop on the biology, prevention, and treatment of relapse after allogeneic hematopoietic stem cell transplantation. thus is the only way that we are going to determine the optimal use of dli and to move the field forward [ ]. so, as we step back and look across the dance floor, do we really find ourdate,dli,attractive? maybe, ifviewedwithinthe context of our other options for recurrent disease after allo- geneic hematopoietic cell transplantation. however, i would argue that maybe it is time for the transplantation community to go the ophthalmologist to get our eyes examined. acknowledgments financial disclosure: the authors have nothing to disclose. references . bar m, sandmaier bm, inamoto y, et al. donor lymphocyte infusion for relapsed hematological malignancies after allogeneic hematopoietic cell transplantation: prognostic relevance of the initial cd þ t cell dose. biol blood marrow transplant. ; : - 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. . levine je, braun t, penza sl, et al. prospective trial of chemotherapy and donor leukocyte infusions for relapse of advanced myeloid malignancies after allogeneic stem-cell transplantation. j clin oncol. ; : - . . collins rh jr, shpilberg o, drobyski wr, et al. donor leukocyte infu- sions in patients with relapsed malignancy after allogeneic bone marrow transplantation. j clin oncol. ; : - . . schmid c, labopin m, nagler a, et al., ebmt acute leukemia working party. donor lymphocyte infusion in the treatment of first hemato- logical relapse after allogeneic stem-cell transplantation in adults with acute myeloid leukemia: a retrospective risk factors analysis and comparison with other strategies by the ebmt acute leukemia working party. j clin oncol. ; : - . . porter dl, alyea ep, antin jh, et al. nci first international workshop on the biology, prevention, and treatment of relapse after allogeneic hematopoietic stem cell transplantation: report from the committee on treatment of relapse after allogeneic hematopoietic stem cell transplantation. biol blood marrow transplant. ; : - . . porter dl, levine bl, kalos m, et al. chimeric antigen receptoremodi- fied t cells in chronic lymphoid leukemia. n engl j med. ; : - . . hardy nm, fellowes v, rose jj, et al. costimulated tumor-infiltrating lymphocytes are a feasible and safe alternative donor cell therapy for relapse after allogeneic stem cell transplantation. blood. ; : - . . bishop mr, alyea ep rd, cairo ms, et al. national cancer institute’s first international workshop on the biology, prevention, and treat- ment of relapse after allogeneic hematopoietic stem cell trans- plantation: summary and recommendations from the organizing committee. biol blood marrow transplant. ; : - . donor lymphocyte infusion: beauty is in the eye of the beholder acknowledgments references erratum to: “measurement of open beauty production at hera” october physics letters b ( ) – www.elsevier.com/locate/npe erratum erratum to: “measurement of open beauty production at hera” [phys. lett. b ( ) – ] ✩ h collaboration received august we have miscalculated the theoretical value of the muon production cross section from b decay in [ ]. the cross section in the visible region derived from the nlo qcd calculation of [ ] should be . ± . nb (instead of . ± . nb given in [ ]) to be compared to the measured value of . ± . + . − . nb which is unchanged. this amended theoretical value is now computed using the peterson fragmentation parameterisation described in [ ]. the lo calculation of this cross section gives . nb (instead of . nb given in [ ]) compared to the value of . nb computed from the aroma monte carlo [ ] which is unchanged. here the updated value of . % is used for the semi-leptonic branching ra- tio for the primary admixture of b hadrons [ ]. the total number of decay muons in the visible region also includes a fraction of % due to secondary de- cays. the changes enter the extrapolations to the full phase space and so other amendments are necessary. despite the large factors involved we give the corre- sponding numbers for completeness. the total elec- troproduction cross section (q < gev ) should be . ± . + . − . nb (instead of . nb) and the total pho- toproduction cross section at w = gev should be ± + − nb (instead of nb). the value of the latter quantity has been amended in fig. which re- places fig. of [ ]. apart from the amended numbers given above the conclusions of the paper are unchanged. ✩ pii of original article: s - ( ) - . fig. . the total photoproduction cross section, σ (γp → bb̄x). the horizontal error bar represents the range of the measurement. the solid curve shows the expectation of the fmnr nlo qcd calcu- lation (full line) with mb = . gev and the mrsg and grv-ho structure functions for the proton and the photon, respectively. the shaded area corresponds to the uncertainty if the factorisation scale changes by a factor of . a change of the renormalisation scale by a factor of leads to a similar result. the dashed line represents the prediction of the fmnr nlo qcd calculation if the mrst [ ] structure function for the proton is used. references [ ] c. adloff et al., h collaboration, phys. lett. b ( ) , hep-ex/ . [ ] s. frixione, m.l. mangano, p. nason, g. ridolfi, phys. lett. b ( ) , hep-ph/ . pii: s - ( ) -  elsevier science b .v. open access under cc by license. - / / http://creativecommons.org/licenses/by/ . / physics letters b ( ) – [ ] g. ingelman, j. rathsman, g.a. schuler, comput. phys. commun. ( ) , hep-ph/ . [ ] d.e. groom et al., particle data group collaboration, eur. phys. j. c ( ) . [ ] a.d. martin, r.g. roberts, w.j. stirling, r.s. thorne, eur. phys. j. c ( ) , hep-ph/ . march , volume , number american association for the advancement of science science serves its readers as a forum for n the presentation and discussion of impor- tant issues related to the advancement of science, including the presentation of mi- nority or conflicting points of view, rather exp than by publishing only material on which the ai consensus has been reached. accordingly, qua :ill articles published in science-including id editorials, news and comment, and book reviews-are signed and reflect the indi- par vidual views of the authors and not official us points of view adopted by the aaas or rive the institutions with which the authors are affiliated. was mo] editorial board mal robert l. bowman willard f. libby i melvin calvin gordon j. f. macdonald a r joseph w. chamberlain everett i. mendelsohn mo farrington daniels neal e. miller john t. edsall john r. pierce par david r. goddard colin s. pittendrigh wrc emil haury kenneth s. pitzer per alexander hollaender alexander rich mai robert jastrow dewitt stetten, jr ero edwin m. lerner, ii edward l. tatum clarence m. zener con dre editorial staff tion editor woi philip h. abelson ser' publisher business manager to dael wolfle hans nussbaum f managing editor: robert v. ormes he assistant editors: ellen e. murphy, john e. all ringle legi assistant to the editor: nancy teimourian he news and comment: daniel s. greenberg, trai john walsh, elinor langer, marion zeiger, hor rosemary galli europe: victor k. mcelheny, flat , ken- prir sington court place, london, w. , england (western ) trol book reviews: sarah s. dees not editorial assistants: isabella bouldin, eleanore task butz, ben carlin, sylvia eberhart, grayce wat finger, nancy hamilton, oliver heatwole, are anne holdsworth, marcia jodlbauer, ruth kingerlee, katherine livingston poll a u advertising staff t director production manager blot earl j. scherago raymonde salama bno sales: new york, n.y., w. st. ( -pe- - ): richard l. charles, robert s. bugbee bec scotch plains, n.j., unami lane ( - - sew ): c. richard callis chicago, ill., w. ontario st. ( -de- - ): herbert burkland poll los angeles , calif., beverly blvd. ( - in - ): winn nance meed editorial correspondence: l ls massa- chusetts ave., nw, washington, d.c. . phone:, sont - - . cable: advancesci, washington. copies of "instructions for contributors" can be top obtained from the editorial office. advertising correspondence: rm. , w. st., new york, n.y. . phone: -pe - . science - * :.. t..?:f ".: ar." atural beauty and conservation science and technology have led to an affluent society, a population ilosion, and a concentration of our people in urban areas. but while number and concentration of human beings has increased, the ality of living has in some ways diminished. the affluence that pro- es so many automobiles brings with it air pollution and great -king lots in the form of expressways. water pollution has robbed of much potential recreation and simple pleasure; once-beautiful ers eiow are little better than open sewers. disposal of the solid ste of cities is a noxious and growing problem. discarded auto- biles increasingly litter our countryside as low prices for scrap ke them practically worthless. president johnson emphasized his concern about these matters in recent white house message on natural beauty. recognizing that ost of our population resides in urban areas, mr. johnson devoted rt of his message to a call for improving the beauty of cities. he ote of the contrasting effects of ugliness and beauty on man's spirit. rhaps he wrote from a background of personal experience, for iny who live in the nation's capital find great pleasure in its num- )us vistas. most cities are not so fortunate as washington. they are istructed on an ugly pattern, and so they will remain, though the ariness may be relieved somewhat if the president's recommenda- is for an open space land program are implemented. this program uld provide matching grants to help urban areas obtain land to ve as open space. in addition, city governments would be helped acquire and clear areas to create parks and playgrounds. part of the president's message was devoted to the countryside. recommended the establishment of additional national parks. who have enjoyed the existing parks will support the needed islation. president johnson sounded another welcome note when stated that he is taking steps to encourage a national system of ils. these would include abundant trails for walking, cycling, and rseback riding in and close to our cities. another part of the message was devoted to water pollution. in nciple, the problems of sewage and industrial wastes can be con- iled by legislation. there are other problems of pollution that were tmentioned in the report and that are of scientific interest. the k of revitalizing appalachia is complicated by the pollution of ter there by acid mine water. when exposed to air, sulfides in coal oxidized, and sulfuric acid is produced. a more subtle kind of lution occurs in rivers like the potomac. the clear effluent from reatment plant provides a rich source of nutrients (fixed nitrogen, tassium, and phosphate) for algae. on sunny days, a great algae om occurs in the slow-moving river. often cloudy days follow, i the algae consume more oxygen than they evolve. the water can ome anaerobic; fish die, and the river may become much like a ver. rhe president proposes only limited action on the problem of air lution; a modest $ million is budgeted for air pollution programs. addition, he has promised to discuss with automobile manufacturers ans of reducing pollution from liquid-fueled vehicles. rhe problems involved in improving the quality of life are difficult; ne are almost insoluble. it is good to find that the matter is getting -level attention.-philip h. abelson o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/ natural beauty and conservation philip h. abelson doi: . /science. . . ( ), . science article tools http://science.sciencemag.org/content/ / / .citation permissions http://www.sciencemag.org/help/reprints-and-permissions terms of serviceuse of this article is subject to the trademark of aaas. is a registeredscienceadvancement of science, new york avenue nw, washington, dc . the title (print issn - ; online issn - ) is published by the american association for thescience by the american association for the advancement of science o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/content/ / / .citation http://www.sciencemag.org/help/reprints-and-permissions http://www.sciencemag.org/about/terms-service http://science.sciencemag.org/ [pdf] intrinsic functional-connectivity networks for diagnosis: just beautiful pictures? | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /brain. . corpus id: intrinsic functional-connectivity networks for diagnosis: just beautiful pictures? @article{habeck intrinsicfn, title={intrinsic functional-connectivity networks for diagnosis: just beautiful pictures?}, author={c. habeck and j. moeller}, journal={brain connectivity}, year={ }, volume={ }, pages={ - } } c. habeck, j. moeller published psychology, medicine, computer science brain connectivity resting-state functional connectivity has become a topic of enormous interest in the neuroscience community in the last decade. because resting-state data ( ) harbor important information that often is diagnostically relevant and ( ) are easy to acquire, there has been a rapid increase in the development of a variety of network analytic techniques for diagnostic applications, stimulating methodological research in general. while we are among those who welcome the increased interest in the… expand view on pubmed europepmc.org save to library create alert cite launch research feed share this paper citationshighly influential citations background citations methods citations results citations view all figures, tables, and topics from this paper figure table figure best practice resting state fmri neuroscience discipline rest clarify biological markers dialog mathematics graphics food consumption stimulation (motivation) citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency highly adaptive tests for group differences in brain functional connectivity junghi kim, w. pan computer science, medicine neuroimage: clinical highly influenced view excerpt, cites background save alert research feed inferring functional connectivity in mri using bayesian network structure learning with a modified pc algorithm swathi p. iyer, i. shafran, d. grayson, k. gates, j. nigg, d. fair computer science, medicine neuroimage pdf view excerpts, cites results save alert research feed comparison of statistical tests for group differences in brain functional networks junghi kim, jeffrey r. wozniak, b. mueller, x. shen, w. pan computer science, medicine neuroimage view excerpt, cites background save alert research feed network optimization of functional connectivity within default mode network regions to detect cognitive decline w. chaovalitwongse, d. won, + authors t. grabowski psychology, medicine ieee transactions on neural systems and rehabilitation engineering pdf view excerpt, cites background save alert research feed quantifying significance of topographical similarities of disease-related brain metabolic patterns j. ko, p. spetsieris, y. ma, v. dhawan, d. eidelberg biology, medicine plos one pdf save alert research feed connectivity differences in brain networks a. zalesky, l. cocchi, a. fornito, m. murray, e. bullmore computer science, medicine neuroimage pdf view excerpt, cites background save alert research feed metabolic resting-state brain networks in health and disease p. spetsieris, j. ko, + authors d. eidelberg psychology, medicine proceedings of the national academy of sciences pdf save alert research feed role of ongoing, intrinsic activity of neuronal populations for quantitative neuroimaging of functional magnetic resonance imaging-based networks f. hyder, p. herman, b. g. sanganahalli, d. coman, h. blumenfeld, d. rothman psychology, computer science brain connect. view excerpt, cites background save alert research feed on the use of correlation as a measure of network connectivity a. zalesky, a. fornito, e. bullmore mathematics, medicine neuroimage pdf view excerpt, cites methods save alert research feed can the default-mode network be described with one spatial-covariance network? c. habeck, j. steffener, b. rakitin, y. stern psychology, medicine brain research pdf save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency graph-based network analysis of resting-state functional mri jinhui wang, xinian zuo, y. he psychology, medicine front. syst. neurosci. pdf view excerpts, references background save alert research feed network homogeneity reveals decreased integrity of default-mode network in adhd l. uddin, a. kelly, b. biswal, d. margulies, m. milham psychology, medicine journal of neuroscience methods pdf view excerpts, references background save alert research feed complex brain networks: graph theoretical analysis of structural and functional systems e. bullmore, o. sporns psychology, medicine nature reviews neuroscience , pdf view excerpts, references background save alert research feed default-mode network activity distinguishes alzheimer's disease from healthy aging: evidence from functional mri m. greicius, g. srivastava, a. reiss, v. menon computer science, medicine proc. natl. acad. sci. usa , pdf view excerpts, references background save alert research feed alterations of resting state functional connectivity in the default network in adolescents with autism spectrum disorders shih-jen weng, j. wiggins, s. peltier, melisa carrasco, c. monk psychology, medicine brain research pdf view excerpts, references background save alert research feed disruption of large-scale brain systems in advanced aging j. andrews-hanna, a. snyder, + authors r. buckner psychology, medicine neuron , pdf save alert research feed the elements of statistical learning: data mining, inference, and prediction, nd edition t. hastie, r. tibshirani, j. friedman mathematics, computer science springer series in statistics , pdf view excerpts, references methods save alert research feed an introduction to the bootstrap m. kenward , pdf view excerpt, references methods save alert research feed the visual display of quantitative information e. tufte computer science , pdf view excerpt, references methods save alert research feed the visual display of quantitative information james w. reidhaar, e. tufte computer science , save alert research feed ... ... related papers abstract figures, tables, and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue microsoft word - white collar beauties.doc jieyu liu soas university of london beauties at work: sexual politics in a chinese professional organization jieyu liu, soas china institute, jieyu.liu@soas.ac.uk this is an earlier version of the published article in nan nÜ: men, women and gender in china, ( ). pp. - . published by brill. doi: . / - p abstract this article explores new forms of inequality experienced by young white-collar professional women in post-socialist china. drawing upon ethnographic data collected during a six-month stay in a chinese company in eastern china, i explore how sexuality is played out in its organizational culture. through an analysis of management attitudes, everyday office encounters and organizational activities, i illustrate that the workplace culture can be eroticized. masculine domination pervades company organization, with women controlled through the process of objectification, which intensifies vertical segregation by gender. despite gendered and sexualized control in the white-collar workplace, i caution against misinterpreting chinese women’s responses by viewing them through the lens of inappropriate assumptions. i indicate how women’s agency may be enacted, and reveal layers of response and resistance in the face of masculine domination at work. key words: sexuality, gender, organizational culture, white-collar profession, urban china introduction during mao’s reign over china, the cultural revolution aimed to erase gender (and other) differences between citizens. these values were rejected in the early s, jieyu liu soas university of london and the largely state-controlled media started to promote feminine figures and womanly values as appropriate role models. as economic development picked up in the s, the beauty economy boomed and has continued to grow ever since; for example, commercial companies employ models to advertise their products and many local governments have sponsored beauty contests to boost tourism. in the shadow of this growing consumerism and deployment of a sexualized femininity in the public domain, the sex industry has proliferated, catering to the demands of the increasing numbers of wealthy businessmen. this re-sexualisation of chinese women means there is a need to examine the new sexual politics and forms of inequality that may have arisen in the chinese workplace. existing studies on gender and work in china focused on sexuality, have examined the life of sex workers, the low-paid service workers. in contrast, this article examines the working experiences of highly educated young professional women, hailed by the chinese media as ‘white-collar beauties’ (bailing liren). despite the media’s depiction of them living an enviable lifestyle in the front line of a pioneering modernity, these professional women are not immune from gender discrimination and sexual consumption. there is a gendered and sexualized story to be told. building upon western feminist literature on gender, sexuality and organization, this article contributes to the development of global literature on gender, sexuality and work, but beyond the existing euro-america model. western scholars have already shown how organisational structures and workplace cultures are both gendered and sexualised, and that this is integral to organizational control and workplace relations. these studies, however, are grounded in a discourse of sexuality markedly different from that in china. under mao, gender was pursued through the desexualisation of women; opening up the economy has re-sexualised jieyu liu soas university of london women but in a context in which the continuance of past restrictions on sexual expression and discussion provide them with little or no opportunity for sexual autonomy. this makes sexualised office encounters and business cultures that young professional women have to negotiate particularly problematic. drawing upon ethnographic data i collected during a six-month stay in a chinese company in eastern china, i explore how sexuality is played out in everyday interactions within the organizational culture of chinese companies, and how the interplay of gender and sexuality contributes to the reproduction of masculine hierarchy and control in the workplace. given the empirical basis of most scholarship on sexuality in organizations is euro-american societies, the local sociality of gender and sexuality is often taken for granted. using a chinese company in china as a case study, this article aims to illuminate the importance of a local socio-cultural context in shaping the contour of sexualized control and resistance. sexuality at work over the last three decades, western feminist scholars have criticized mainstream organization studies for overlooking the issue of sexuality. like gender, sexuality is an integral part of work relations. at one end of the spectrum – sex as work – is the scholarship revealing how women are expected to perform aesthetic and sexual labour; sexuality is literally ‘part of the job’. in the mainstream labour market there are still many roles designed to incorporate women’s sexual appeal with a view to attracting male customers; for example, service roles such as like flight attendants and waitresses. at the other end of the spectrum – sex in work – is the investigation into how sexual relations exist as a dialectic of control and resistance within jieyu liu soas university of london organizations. for example, male bosses might exploit the relationship with their female secretaries; male workers may develop predatory sexual discourses and shop floor cultures that derogate and segregate women. in spite of this, or perhaps because of it, women actively engage in sexual politics. rosemary pringle found that female secretaries flirted with their male managers in order to gain concessions or even pursue for fun this kind of interaction. peter fleming’s study of call centre workers exposed the organization’s role in purposely controlling sexuality, and how an organization’s apparent openness to sexuality masked how only certain sexual expressions deemed managerially useful were condoned. the sex-in-work scholarship informs the discussion of my data. to help analyse sexuality at work, i employ objectification theory in an analytical framework. according to the feminist theorists nussbaum and langton key features involved in the process of objectification include: . instrumentality (treating a person as a tool for the objectifier’s purposes); . denial of autonomy (treating a person as lacking in autonomy and self- determination); . inertness (treating a person as lacking in agency and also in activity); . fungibility (treating a person as interchangeable with other objects); . violability (treating a person as lacking in boundary-integrity); . ownership (treating a person as something that is owned by another); . denial of subjectivity (treating a person as someone whose experiences and feelings need not be taken into account); . reduction to body (treating a person as identified with their body, or body parts); jieyu liu soas university of london . reduction to appearance (treating a person primarily in terms of how they look); . silencing (treating a person as if they are lacking the capacity to speak). embracing these features, the objectification of women involves the act of disregarding the personal and intellectual abilities of a woman, and reducing her worth or role in society to that of an instrument for sexual pleasure that she can produce in the mind of another. this sexual objectification of women is widespread in western culture, permeating advertising, popular consumption, and of course pornography. china’s market reforms, commercial culture and public discourse also embrace this sexual objectification of women, and this ‘sexualization of the economy’ has infected organizational culture. i utilize this sexual objectification framework to reveal the process by which female employees are sexualized, and how the sexualization assists in the maintenance of gendered and hetero-normative control and hierarchy in the organization. while exposing the organizational mechanism reproducing gendered and sexualized control, i also warn against the practice of misinterpreting chinese women’s responses by viewing them through the lens of inappropriate assumptions. although feminist scholars are generally more sensitive of inequalities and asymmetries on a global scale, there is a still long way to go toward understanding gender inequalities in east asian societies: influential feminist scholarship remains grounded largely in an euro-american axis that has defined its priorities. to date, major attempts to de-imperialize feminism have been framed in terms of an opposition between first world and third world women, or more recently between the global north and the global south. while it is necessary to develop feminist analyses of the widening gap between rich and poor nations, the effect of such a jieyu liu soas university of london focus has been to exclude chinese women who are neither western nor from the global south. by grounding analysis in local socio-cultural meanings and mechanisms of the chinese gender-sex system, this article aims to shed fresh light upon the ways in which gender and sexuality are integral to the processes of compliance and resistance of masculine domination at work beyond euro-american parameters. western studies on sex in organizations are grounded in a socio-cultural discourse of sexuality markedly different from that in china. traditionally, it was acceptable for chinese men to have multiple sexual partners (with concubines or prostitutes), while women were valued for their chastity. one mechanism to monitor the sexual purity of women was through the segregation of the sexes from the early years of life; the ‘inner’ space confined women to the household, out of public sight, was seen as necessary counterpart to the ‘outer’ space where men moved freely. whether to cross this boundary or not was critical to distinguishing between women who were ‘respectable’ or ‘pariahs’. the obsessive concern with women’s respectability in pre-modern writings (which conveyed messages that women should avoid suspicion, shun male company, not gossip) implied that sexuality was central to women’ social identity. by contrast, the social status of men was defined occupationally, dividing those who labor with their minds (the scholar elite) from those who labor with their hands (farmers and artisans). twentieth-century reforms targeted the spatial concealment of women and moved them into the public space, outside the home, through mass mobilization into women’s employment. the link between sexuality and women’s social status, however, was never contested and in the official maoist discourse, women were the principal targets and agents of sexual morality and respectability. although post- jieyu liu soas university of london socialist china has witnessed a boom of sexualization and commodification of women’s bodies, women’s sexual desire and autonomy remain moralized in the public space and continue to be key markers of ‘reputable’ women in the reform era. indeed, boundary-crossing sex workers and (the few) women who write about their sexual experiences are publicly condemned as morally abhorrent and disreputable, while businessmen are free to enjoy the sexual consumption of women. this wider context and the deeply engrained link between sexuality and women’s social status is the key to understanding the ways in which sexualized control and women’s resistance take place in chinese workplaces. women’s respectability is closely tied to their sexual morality. ‘respectable’ women’s conformity to gendered sexual control, however, cannot be viewed simply as a sign of their powerlessness and so a more nuanced analysis is required to account for women’s agency. feminist scholars of non-western societies have highlighted the use of the ‘gender mask’ for women to gain social acceptance, and to demonstrate their capacities to produce ‘public transcripts’ appropriate to the needs of the moment. thus, in a public space such as the office, women conform to a moral script in order to maintain their own (and their family’s) respectability. there are also other social factors, such as the lack of state welfare provision, which mean that wider family and kinship networks remain the main source of funding and support for individuals in contemporary china, and thus for a woman to damage her reputation may have profound economic and social implications in a relational society. and so, while i agree with the call by western feminists to find new ways to communicate about sex and to reframe the boundaries of what is acceptable, caution should be raised against any simplistic demand grounded in a western feminist ideal for chinese women to assert sexual autonomy for themselves publicly. jieyu liu soas university of london the company this article is based upon data collected through an ethnographic study of a company situated in the yangtze river delta in eastern china. the delta, which includes shanghai, is one of the economic zones designated by the state for development of the market economy and has enjoyed rapid growth since the economic reforms of the s. the company is one of the major state-owned foreign-trade companies in the region, specializing in exporting machinery; it has an annual export volume among the highest in eastern china. because of its size, stature and profitability, it is a desirable employer for many local graduates. during the economic restructuring of the late s many older staff took early retirement from the company, and as a result, the age of employees now range from to , with the majority in their late s and early s. in , when i did my fieldwork, the company occupied two floors of a skyscraper and employed approximately staff split into in four departments: sales ( ), finance ( ), human resources ( ) and technical support ( ). through a local contact, i was introduced to the general manager of the company and allowed to work as an intern in the sales department for six months. during my stay, i conducted in-depth and repeated interviews with various members of staff in the company and took extensive observation notes. the company staff was aware of my identity as a researcher, and i was given considerable freedom to walk around, attend meetings and talk to employees. after i completed the fieldwork, i remained in contact with some interviewees in order to gain insights into developments in their life and the company. the sales department, which was generally viewed as the core of the company, was sub-divided into six sectors depending on export region. there were three types of positions: sales assistant (most junior in the department), sales manager, and jieyu liu soas university of london section manager (most senior in the department). when i first started my fieldwork, there were six male section managers, seven male sales managers and one female sales manager; twenty-four female sales assistants and ten newly recruited sales assistants (four men, six women, all of whom had graduated from top universities in the region). by , the four men from the recruitment round had all became sales managers, including two section managers, but the six women were all still sales assistants. job segregation by gender had significant material consequences for women employees. the wage structure of the company consisted of a basic wage, welfare allowances and a bonus. the first two components were calculated according to a number of factors such as educational level, years of service and positional pay grade. the lowest level pay grade of a sales manager equalled the highest level pay grade of a sales assistant. however, the major differentiating factor in take-home-pay between grades was the bonus. the bonus of a sales manager was equal to per cent of the profit contribution of all deals completed, and in a good month this could be more than a sales assistant earned in a year. sales assistants, who may have made a significant contribution to the successful completion of a deal, received a bonus that was set within a fixed range with the exact figure determined by their line manager’s assessment of their performance. this meant that while a sales manager’s income was linked to the success of the company, the income of a sales assistant was subject to labour control. in addition to the officially documented wage structure, there was an unspoken, opaque practice that was crucial to the economic polarization in the company: the annual distribution of dividends from company shares. although the jieyu liu soas university of london company was officially classified as state-owned, up to per cent of its registered share capital was held by management and, unbeknown to sales assistants, sales managers were invited to buy company shares at a discounted price. since the company was both highly profitable and had grown considerably in a relatively short period of time, several managers had become millionaires through the dividends they were paid. this polarizing income gap between sales managers and sales assistants was built upon a vertical segregation by gender but also paradoxically set out the material conditions in which gender and sexuality were played out in the company. the official stance when i first started working at the company the human resources assistant, xiao chen, gave me a booklet entitled regulations on employees’ everyday behaviours. the booklet had eight pages in total dealing with everyday manners, office health and safety, and workplace discipline. the first page detailed the appearance requirements in the workplace. men were not allowed beards; to wear short trousers, a vest or sleeveless shirt. women were not allowed to wear sleeveless shirts, tummy revealing, low cut, or tight clothing, mini-skirts (skirts needed to be at least knee-length), or see- through clothes. the different clothing requirements for men and women were built upon an assumption that women’s gender presentation is embedded in sexual ways. the prohibited clothing for women was associated with deviated women’s sexuality while the men’s dress code simply differentiated between casual and formal; i.e. men’s sexuality was not used to define the parameters of their presentation in the workplace. as a consequence, management’s different treatment of gender display sent an implicit message that women’s sexuality should be monitored and controlled in the jieyu liu soas university of london organization. in practice, i noticed that while women complied with the dress code – all women wore feminine, but did not dress sexually, the style and colours of women’s clothing were diverse. moreover, none of the women wore a suit or formal dress; and during my entire stay i only saw one woman (sales assistant) dressed formally, and that was because she was about to fly to a trade fair that day. all men wore open collar shirts and jackets; on the days when clients were visiting, they wore suits to comply with the company’s requirement. although the official regulations prescribed a desexualization of women’s bodies to maintain the organizational image, my interviews with senior management revealed another story. when i asked how general manager wang felt about managing female employees, he reflected, “women have significant functions. for example, in our industry, the pressure is high and there is lots of boring work. if all employees are men, i feel it very difficult for the organization”. mr. wang was married, in his mid-thirties and also the party secretary for the company. perhaps because of his position, he was cautious in his words and tended to give ambiguous or indirect answers during my encounters with him. here he revealed that women employees had significant functions but did not specify how. instead he implied that the presence of women would reduce the pressure on men’s work. however, most of his males colleagues were more explicit, and the phrase nannü dapei, ganhuo bulei (if men and women work together, the work won’t be tiring) featured frequently in my interviews with them. how would this pressure be reduced for men? during a conversation with a section manager, he gave me a clear answer to the question. q: what is the most suitable proportion of women in a workplace? jieyu liu soas university of london a: i like a workplace with lots of women. it feels very pleasant. q: how? a: i don’t know how to say. it feels pleasant with women around, doesn’t it? feeling like having one on the left and one on the right, it is extremely pleasant. q: how will this arrangement play in the workplace? a: it can stimulate productivity. life won’t be boring. through flirting with women colleagues, the atmosphere will be lifted up. i hope that in my section there are considerable levels of office banter as i find it can be inspiring. the interviews with male managers indicated an encouragement of an eroticized workplace culture, which they considered conductive to boosting morale and productivity. this eroticization of the organization is formulated through, and symbolized in, the interactions between men and women at work. the underlying message is that women are brought into the workplace to stimulate male workers. the discrepancy between the management’s desire to eroticize workplace culture and official regulation on appearance creates a paradox for women. while their desexualized body is an important symbol of the organization’s professional image for outsiders, female employees were sexually objectified by the masculine management team within the organization; one consequence of this was that female employees were routinely subject to sexual innuendo at work. the eroticized workplace culture also exhibited a new form of masculinity in post socialist china. this masculinity is a local presentation of ‘transnational business masculinity’, which is characterized by ‘its increasingly libertarian sexuality, with a growing tendency to commodify relations with women’ and emerges as the dominant form on a global scale as a result of geopolitical struggles, multinational corporations, jieyu liu soas university of london global markets and transnational media. in the context of east asia, this hypermasculinity has been naturalized as ‘part and parcel of the economic development of many states and firms’. zurndorfer points out the historical link between the past and present in the formation of chinese masculinity; men’s overbearing hegemonic behaviour in the reform era is closely linked to the traditional polygyny in pre-modern china, and their emasculinization in the pre-reform era. office banter xiao zhang was slim, with a small good-looking face, and in her late s. she had a masters degree in human resources management, and was head of the human resources department. this made xiao zhang the only woman in the management team, and she often joked with me that the human resources department was a women’s department, and the least important section in the company. every three months, the company held a two-day management meeting. after i had been in the company for a couple of months, i attended one of these occasions. xiao zhang, her deputy, and i were the only women at the gathering. in the opening report by general manager wang, he noted the company’s initiative to build a factory on a recently purchased piece of land. during the course of his presentation, wang mentioned that it would be good to plant trees around the factory, then turned to xiao zhang, smiled, and said ‘the tree planted by us two will grow fast and strong’. all the other managers laughed. i glanced at xiao zhang and she remained silent without any facial expression. i then looked at general manager wang who seemed pleased with the reaction to his comment and uninterested in zhang’s reaction. jokes like this occurred several times during the morning meeting. at lunchtime, all the participants of the meeting were invited to have a meal at a jieyu liu soas university of london nearby restaurant. my table consisted of general manager wang, his deputy, a few section managers, and all three women. after asking xiao zhang how her wedding preparations were going, mr wang asked ‘why did you choose him? i heard he looked like me’. xiao zhang replied without much facial expression, ‘yes, both you and him are round’. then laughter burst out on the table. later, the deputy manager turned to me, and said that since i had the highest degree at the table, he would like to know my opinion in mate selection. he set out a scenario in which i should assess the men at our table as potential marital partners for myself, and asked whom i would select and why. i thought as an outsider to the company, i would be excluded from the banter and so his proposal took me by surprise. in response i explained mate selection in academic terms and diluted the sexual element. i could tell the deputy manager was disappointed with my answer as it did not achieve the ‘atmosphere stimulating’ effect he hoped for. after this close experience of office banter, i met with xiao zhang separately, and asked her to reflect upon these interactions. age and marital status seemed to play a key role in the women chosen by men as targets for their banter. xiao zhang felt she was the youngest among the three women present, not married, and so she the softest target. when i asked to elaborate, xiao zhang replied: the first time i was really uncomfortable. they told dirty jokes about me, i wanted to find a crack on the ground and slip into it. in fact, at the time i wondered if he was joking or meant it. i felt really awkward and didn’t know what to do. nowadays i am completely used to it. i am neither angry nor do i mind. i have no reaction. when i hear the joke, i feel the same as when someone askes ‘have you eaten?’ jieyu liu soas university of london apart from the general manager, other male managers, including those of a rank similar to her also made jokes at xiao zhang’s expense. she recalled: look, sometimes when we have lunch together, sales manager a will say something to me like ‘beauty, you are my flower, you are my lover’. b, c, d (other male managers) also liked to joke at me. when i was planning my annual leave, a section manager heard and said, in front of my assistant xiao chen in the office, ‘how come you planned to go to sanya again? haven’t you already been there? we two went there together once’. xiao chen threw a glance at me immediately. i knew that she took it as true. i explained to her, ‘he is joking, don’t take it seriously’. xiao zhang’s experiences were common and permeated the interactions female sales assistants had with male managers. section manager zhou was fond of telling jokes at his female assistant’s expense but he also commented there should be a boundary, and that was physical contact; that is, men should not have a physical relationship with a female colleague: a: telling dirty jokes at women can satisfy a dry ‘erotic’ craving. q: what does a dry craving mean? a: that you want to play with a woman but you cannot have a real sexual relationship with her. married men already have responsibilities and don’t need any further burden. occasionally the staff stepped over section manager zhou’s boundary. before my time at the company there was a married sales manager who fell in love with one of his sales assistants and divorced his wife to marry his assistant. both parties left the company soon after. in the case of singleton employees involved in a relationship, jieyu liu soas university of london the company authorities took steps to separate the two people as they did not consider it professional for a husband and wife to work alongside each other. for example the woman would be moved out of the sales department into a supporting section— effectively a demotion because wages were lower outside the sales department. however, the man involved in the office marriage was more likely to be promoted, or even given greater responsibility as it was assumed he now had a family to provide for. in the six years after , four couples followed this pattern. recent scholarship on sexuality in organization studies has concerned itself with whether office banter brings pleasure or harassment to an organizational setting. the chinese office dynamics researched here indicate that the answer to this question is complicated. first, the office setting provided an arena for office banter to take place. within the company, apart from separate offices for the general manager, deputy general manager and a few meeting rooms, all employees operated in an open plan space with individual desks compartmentalized by panels up to the head level when one sits down. therefore, employees peering over these panels to chat to those nearby while remaining seated was common practice. two types of conversations took place between men and women on a day-to- day basis. the first type, work-related conversations, involved managers delegating tasks to the sales assistants. these conversations did not involve sexual connotations. section managers and above tended to be more direct in their orders while sales managers (who were a rank higher than women assistants but relatively low within the organizational hierarchy) sometimes opened the conversation by complimenting the women; for example, by saying ‘xiao zhang, since you are always so effective and fast, please help to get this done for me’. by assessing men’s position in the jieyu liu soas university of london organization, and their relation with them, women sometimes bargained with the sales managers when these requests were made: for example asking them to buy their lunch, or to bring them gifts from a forthcoming overseas business trip. from my observations of these interactions, i felt that women genuinely found such interactions pleasing. the second type of conversation involved sexual banter in the office space. on most such occasions, the sexual banter happened all of a sudden: for example, the joker saw something in the news or heard something that prompted them to a sexual joke, which had nothing to do with the work in hand. analysing at the contents of the men’s sexual jokes, the discursive pattern usually involved an imaged affair between the joker and his target. it was often married senior managers (section managers and above, although occasionally some sales managers) who told sexual jokes. to an extent, these jokes provided a discursive landscape that embraced their paradoxical stance towards extramarital affairs: on the one hand, the managers disputed extramarital affairs as something to be avoided, but on the other hand, they were active in constructing imagined extra-marital relationships through the practice of joking. the jokes therefore provided an avenue for a sort of sexually cathartic expression enabling the men to play out a fantasy without disturbing the harmony of their family life. through this discursive repetition, a sexual hierarchy was established and symbolized in contrast with the subordinate expressions of feminine desire and an aggressive drive of masculine desire. in general women told far fewer jokes than men because of their lower position in the organizational hierarchy. when they did tell jokes, they were mostly oriented towards sales managers (i.e. the rank closest to them) and concerned with the jieyu liu soas university of london romance between the one being joked about, and his wife/girlfriend. none of the women told jokes that involved themselves as the person implicated in the relationship. the women, among themselves, sometimes gossiped about their male colleagues, covering topics such as personality (e.g. whether they were generous or mean), and dating histories (e.g. whether they philandered or not), but i was not privy to any conversations regarding male colleagues’ bodies in contrast with the open comments made by men about their female peers. when considering the impact of gendered sexual banter on organizational control, men’s telling of sexual jokes at women was grounded in their sexual objectification of women, and continually reinforced through both formal and informal communication. women were considered an instrument for men’s pleasure and a tool to boost morale and productivity for the company (instrumentality). by imposing an imagined relationship between the woman being joked about and the joker, the joker claimed ownership of the woman and denial of her autonomy and subjectivity, often producing the silencing effect. through the process of sexual objectification, women’s position as a second-class citizen in the organization was symbolically reinforced. agency in public sexual discourse remains largely a male privilege. men who initiated sexual jokes were clearly in favour of such a practice, claiming this to be an effective mechanism for stimulating the office atmosphere and bringing pleasure to all. men who were good at telling sexual jokes were considered good ice- breakers by senior management – a desirable quality in a client facing environment, which in turn enhanced their perception among senior male colleagues and so ultimately benefited their career development. by contrast, female employees were jieyu liu soas university of london uncomfortable with the practice in their initial encounters but needed to learn to live with it due to its routinization in organizational culture (on average four to five times a day). for these women, something that men claimed was pleasurable frequently bordered on sexual harassment, with stressful consequences for young unmarried women. unlike sex workers, who have already crossed the moral boundary and are so much freer to engage in sexual joking, the intersection of gender and professional class put these women’s sexuality under a strict moral constraint. i did not encounter any woman in the company who freely and actively responded when sexually joked at in the public office setting; women’s silence was the most common response. however, women’s silence in public sexual discourse should not simply be interpreted as a sign of their powerlessness. because of the way in which women’s social status is judged by her sexuality, the damage to her sexual reputation is far more detrimental in a relational society. there were rumours in the organization about a woman from another foreign trade company that was good at ‘everything’ (including sexual joking) but because of this she was nicknamed ‘public toilet’ by the men, casting a dark cloud over her reputation. through the repetition of rumours such as these, an implicit warning was sent out to advise people to distance themselves from this type of women. taking into account the consequences of their behaviour in a society that put so much emphasis upon relational building and reputation, women considered it wise to appear silent and expressionless for the sake of maintaining their respectability. there were also layers of responses contingent upon the context in which women faced men telling sexual jokes in public. in a confined masculine group setting such as the formal management meetings, women always remained silent when sexually joked at. in an everyday office setting, women strategized their jieyu liu soas university of london responses by assessing the jokers’ position in the organizational hierarchy. if the joker was a man from the senior management team (general manager and his deputy and section managers), women largely conformed to public scripts of masculine domination in sexuality; this was conditioned and facilitated by men’s bureaucratic power. yet after initial stressful encounters, women trivialized them and accepted the jokes as part of their day-to-day job. if the joker was a sales manager, women sometimes fought back by either invoking non-sexual jokes or emotional means to discredit the joker. mr jing was years old, single, and a sales manager. during my time at the company, i often observed him walk around the office telling sexual ‘jokes’ at women. on one occasion, a female sales assistant named yin had just asked me my age when mr li passed by and overhead our conversation. he suddenly commented: ‘i like eating both the big and small’. in pre-modern china, the ‘big’ implies the wife and the ‘small’ implies the concubine whilst eating is an indirect way to infer ‘sleeping with’. by invoking this classical chinese saying, mr jing tried to objectify both the sale assistant and me as his sexual compliance. yin answered back sternly, go away, clean your mouth. afterwards, yin warned me that i should be cautious around mr jing as he had a reputation for making sexual jokes in an attempt to gain the attention of women, and was notorious for being persistent. other women assistants showed convulsion or chose deliberate avoidance if he came near. as there was no company policy or procedure for dealing with sexual harassment at the organization, warnings from other women about certain men had become a self-initiated protective mechanism to monitor men in the office. jieyu liu soas university of london not all men participated in telling sexual jokes. a couple of male sales managers confided in me that because they were shy, they did not know how to speak to women. they did not know how to tell jokes, let alone sexual jokes. as men in senior management set the tone by telling sexual jokes, the hegemonic corporate masculinity of the organization entails this aspect, which in turn creates a burden for men who did not fit with this model. the routinization of men’s telling sexual jokes at women reinforced and reproduced the heterosexual-normality model, which made it impossible for homosexuality to emerge at work. in post-socialist china, gay clubs, telephone support lines and other grassroots and activist organizations have started to emerge in some of the larger cities. despite of its visibility, homosexuality is still closely associated with aids, crime, sickness and abnormality. all interviewees expressed surprise or shock at my question about homosexuality in the workplace, and generally talked about them as the ‘other’ in the society. cheerleaders office banter is a ritualised practice central to organizational culture which takes place at an interpersonal level in a public sphere. here i examine collective organizational activities imbued with gendered and sexual meanings. one of the key features of state-owned companies, like the one where i did my research, is the tradition of regular collective events for employees. these events are considered part of an employees’ welfare package and may be sports-related, team-building events or festival celebrations. when speaking of such events, general manager wang commented: jieyu liu soas university of london since the economic reform, chinese society has entered a stage in which everything is measured economically. this is not necessarily a good thing. through these events, perhaps the state hopes to strengthen citizens’ faith and spiritual mood. these collective activities aim to boost the collective ideals and foster team spirit. mr. wang felt that the collective activities of state-owned companies had an enduring relevance and were a necessary state control to infuse young people with collective ideals. during my stay in the organization, there was a men’s basketball event. the company needed to form a basketball team to compete with teams from other state- owned companies in the region and the collective spirit of each company would be expected to be on show throughout the event. for these events it was an unspoken rule that everyone invited must take part and if they chose not to participate they would be considered selfish and lacking in collective values. given that the preparation, and the event itself, took place in the employees’ spare time, i.e. breaks and weekends, this request was all the more demanding. the senior management of the participating companies decided that, to enable women to participate in a “men’s basketball event” each company also needed to organise a team of “basketball babes” (lanqiu baobei) to choreograph and perform a cheerleading routine. when this decision was confirmed, human resources manager xiao zhang was assigned the task of organising the company’s team of basketball babes. she did so by carefully excluding employees with children and targeted young unmarried women and married women with no children. recruitment for the team jieyu liu soas university of london went well with limited resistance. the only significant exception was miss wang, who said: zhang asked me to be a basketball babe, explaining that it was a political task. if it is classified as a political task, one has to complete without any asking. but because every day we already work quite late, adding this political task, i felt it was too much to take on so i made an excuse of being not well to turn down her request. later i told my mother and she scolded me badly, because she knew that if i turned it down, people at my workplace would have a bad impression of me. miss wang’s mother was right to be concerned, xiao zhang later confided in me that she felt miss wang did not want to be part of the team, and so she decided to exclude her from other activities, including work related opportunities. because the cheerleading team needed to rehearse at weekends, during all lunch breaks, and some evenings they sacrificed considerably more time preparing for the event than the men’s basketball team (which practiced only at weekends). however, the main discontent in the team arose over how much of a woman’s body should be revealed during the performance. although male managers at the company had no direct link with the cheerleading team, some sought to influence the women’s attire, saying that women should wear something to “excite one’s eyeballs” (ciji yanqiu). such a request was met with resistance from most women, and some even cited the workplace dress code which noted that low cut tops or mini-skirts were not allowed. during the negotiation over the women’s clothing, the male management gave a distorted discourse of women and modernity: they claimed the women assistants were too conservative and traditional to wear revealing clothes. ultimately a compromise was reached: the company’s basketball babes wore a short sleeve t- jieyu liu soas university of london shirt revealing the waist but not their cleavage and a mini-skirt but with tight shorts underneath. during the weekend before the match, i received a call from the human resources manager xiao zhang in which she explained that one of the cheerleaders had fallen ill, the team required a replacement urgently, and would i step in. had it not been for the fact that i was at the final stage of my fieldwork, i would have had little choice but to take part. after i declined, xiao zhang managed to talk another assistant into cheerleading at the last minute. on the day of match i sat in the audience with the employees of the participating companies. during the cheerleading performances i often heard laughter and explicit comments about the women’s bodies from men in the audience: why bother to dance since the legs are so round?; “when talking about breasts, there are no proper breasts; when talking about buttocks, there are no proper buttocks”--implying these body parts are not sexy enough. later, in the interviews with male managers, some commented that “although it was a men’s basketball game, the basketball babes were the centre of attention”. when the event was over, the women’s embodied performance remained the topic of office banter for a while. reflecting upon this event, both women and men expressed their doubt over the extent to which such an event boosted the collective ideals among employees. this basketball event displayed a heterosexual model of workplace relations between male employees (athletes) and female employees (support actors), reinforcing a hegemonic masculinity and a sexualized femininity as well as institutionalizing heterosexual normality. moreover, the event demonstrated key features involved in the objectification of women. through the male gaze, women as a group became a tool to satisfy men’s desire and pleasure (instrumentality). denied jieyu liu soas university of london subjectivity and autonomy, women’s bodies were talked about, caricatured and consumed. the personal and intellectual capabilities of a woman were reduced to her body parts and through this objectification, a woman employee become a sex object, valourized and devalued, which in turn contributed to her second-class treatment in the workplace. feminist writers argue that sexual objectification is often linked to and caused by social inequality. organization culture is not immune to wider socio-cultural discourse and in some respects the objectification of women in the chinese company replicated the model of sexual economy in the post-socialist china. zurndorfer’s analysis of the cultural discourse of china’s sexual economy, reveals how a sexualized landscape forms part of a wider public discourse which allows the bodies of young and intelligent women to be commodified and commercialized as economic resources. similarly, in this company, gender inequality was institutionalized in the form of a vertical segregation between men and women; through a vicious circle the economic polarization by gender defined the hierarchical position between the exploiter and the one being exploited. female employees were symbolically forced to ‘sell’ their bodies for the pleasure of collective consumption of men who possessed more economic resources. the public objectification of women is therefore closely linked to economic inequality between women and men within the organization and shaped by wider socio-cultural discourse in china. conclusion this article explores the work experience of white collar professional women, mostly from the only child generation. in comparison with their mothers’ generation of manufacturing workers, this generation enjoyed an occupational mobility through the jieyu liu soas university of london educational investment they benefited from as the only child. however, the post-mao economic reform has also witnessed the emergence of a sexual economy in which young women’s bodies had become sexualized and commodified. this wider economic transition subjects these educated professional women to new forms of inequality at work. through an analysis of management attitudes, everyday office encounters and organizational activities, i have illustrated the way in which eroticized workplace culture has resulted in a form of domination and control of women through the process of sexual objectification. sexual innuendo is implicitly encouraged by management to enhance productivity and morale. facilitated by the vertical segregation between men and women, male-initiated sexual jokes were often intended to introduce expressions of subordinate feminine desire. when sexually joked about, women did not find this a pleasant experience as agency in public sexual discourse remains a male privilege. this sexual hierarchy in turn contributed to the reproduction of gendered segregation in the workplace. while exposing the organizational mechanism in reproducing gendered and sexualized control, i warn against the practice of misinterpreting chinese women’s response by viewing them through the lens of inappropriate assumptions. a more nuanced analysis reveals women’s agency and layers of resistance depending upon the context and men’s position within the organizational hierarchy. even when women remain silent and expressionless, their conformity to public scripts on sexuality should not be used as a measure of their powerlessness. their response should be understood within the local sociality of gender-sex system in china which is grounded in a deeply engrained link between sexuality and women’s social status. jieyu liu soas university of london in a relational society that puts great emphasis upon reputation and networks, with profound economic and welfare implications, professional women conform to maintain their social ‘respectability’. through the case study in china, this article reinstates that sexuality is deeply embedded in local social relations and speaks to the literature on sexuality in organization studies which hitherto has been mostly based in euro-american societies. would re-eroticization of workplace culture bring pleasure or harassment in an organizational setting? the chinese office dynamics indicate that the answer to this question is complicated and the pleasure for women was dependent upon the contents, where and in particular, who possessed the agency in sexual encounters. given that china is a place in which sexuality is closely tied to defining women’s social identity and society is highly relational and emphasizes reputation, the emancipatory potential of re-eroticization of organizations could be premature for women. instead, this article calls for the need to pay greater attention to the ways in which local sociality of gender and sexuality shapes the contour of control and resistance within the workplace rather than being trapped in a dichotomy of pleasure and coercion. gary xu and susan feiner, “meinü jingji/china’s beauty economy: buying looks, shifting value, changing place,” feminist economics ( ): – . yang jie, “gender, body politics, and the beauty economy in china,” signs ( ): – . harriet zurndorfer, “men, women, money, and morality: the development of china's sexual economy,” feminist economics . ( ): - . elaine jeffreys, china, sex and prostitution (london: routledge, ). here i follow the social constructionist’s definition of sexuality and consider sexuality as socially organized through the institutions of society and sustained by a variety of discourses, scripts and everyday practices. the following books have examined how sexuality featured in work in post- jieyu liu soas university of london socialist china but the occupations their studies focus upon are either sex industry or front line service industries. zheng tiantian, red lights: the lives of sex workers in postsocialist china (minneapolis: university of minnesota press, ). amy hanser, service encounters: class, gender, and the market for social distinction in urban china (stanford, ca: stanford university press, ). eileen otis, markets and bodies: women, service work, and the making of inequality in china (stanford, ca: stanford university press, ). for example, lisa adkins, gendered work: sexuality, family and the labour market (buckingham: open university press, ); peter fleming, “sexuality, power and resistance in the workplace,” organization studies ( ): – . i have discussed elsewhere the sexualized business culture and its consequences for professional women; see jieyu liu “sexualized labour? white collar beauties in provincial china,” in east asian sexualities: modernity, gender and new sexual cultures edited by stevi jackson and jieyu liu with juhyun woo (london: zed books ), pp. - . by contrast, this article focuses upon women’s everyday encounters with their co-workers in the workplace. christine l. williams, “sexual harassment and sadomasochism,” hypatia ( ): – . see adkins, gendered work, page - . pamela abbott and melissa tyler “chocs away: weight watching in the contemporary airline industry,” sociology ( ): – . christine l. williams, “sky service: the demands of emotional labour in the airline industry,” gender, work, and organization ( ): – . karla erickson, “performing service in american restaurants,” space and culture ( ): – . rosemary pringle, secretaries talk: sexuality, power and work (london: verso, ). david l. collinson, managing the shopfloor: subjectivity, masculinity and workplace culture (berlin: walter de gruyter, ). see fleming, “sexuality”. martha c. nussbaum, “objectification”, philosophy & public affairs, ( ): - . please see page . rae langton, sexual solipsism: philosophical essays on pornography and objectification (oxford: oxford university press, ), pp. - . see langton, sexual solipsism. pp - . see zurndorfer, “men, women, money and morality”. p . jieyu liu soas university of london see chandra talpade mohanty “under western eyes: feminist scholarship and colonial discourses,” feminist review ( ): - . gayatri chakravorty spivak, “can the subaltern speak?,”, in colonial discourse and post-colonial theory: a reader ed. by patrick williams & laura chrisman (new york & london: harvester/wheatsheaf, ), pp. - . patricia buckley ebrey, women and the family in chinese history (hove: psychology press ). pp. - . susan mann, gender and sexuality in modern chinese history (cambridge university press ). pp. - . see mann, gender and sexuality in modern chinese history. p . liu jieyu, gender and work in urban china: women workers of the unlucky generation (london and new york: routledge ). harriet evans, women and sexuality in china: female sexuality and gender since (london: bloomsbury academic ), p . evans discusses the significant gendered consequences of official discourse on sexuality. despite the rhetoric of equality, women were still defined in ‘scientific’ terms as essentially different from and less sexual than men. in this monogamous picture, women were represented as the principal targets and agents of sexual morality and reason, so the double standard implicit in the confucian principle of female chastity was recast in a gender-specific identification of female responsibility for the maintenance of social and sexual order. geng song and derek hird, men and masculinities in contemporary china (leiden: brill ), p . through talking to white collar men, song and hird find while there are diverse masculinities in everyday practice, a biomedical model of innate gendered attributes pervades in the workplace, which impedes and limits women’s career prospects. some ethnographic studies have found that double standards of sexuality between genders among the urban youth in china may not be as strong as in previous generations; see james farrer, opening up: youth sex culture and market reform in shanghai (university of chicago press ); william jankowiak, “chinese youth: hot romance and cold calculations,” in restless china, edited by perry link, paul g. pickowicz and richard madsen (lanham, md: rowman and littlefield, ), pp. - . in contrast, the narratives of my interviewees – the first adult cohort of the only child generation –revealed continued and significant double standards of sexuality and morality. one possible explanation is that this study was conducted in a provincial city where the youth were in some way jieyu liu soas university of london behind their counterparts in more international cities such as shanghai. another possible explanation is the characteristics of researchers, i.e. the samples used by farrer and jankowiak may have been prone to include a segment of youth who were particular more open to western values. a national survey- based study revealed that china’s youth may be more sexually active but double standards for what sexual behaviour in terms of gender is acceptable appear to be strengthening; see william parish, edward laumann and sanyu, a. mojola “sexual behavior in china: trends and comparisons,” population and development review ( ): – . see colette harris control and subversion: gender relations in tajikistan, (london: pluto press ). pp. - . colette harris muslim youth: tensions and traditions in tajikistan (boulder, co: westview press, ). nitya rao “male ‘providers’ and female ‘housewives’: a gendered co-performance in rural north india,” development and change ( ): – . shang xiaoyuan and wu xiaoming “the care regime in china,” journal of comparative social welfare, ( ): – . andrea cornwall and susie jolly, “sexuality and the development industry,” development ( ): – . i have discussed elsewhere how a gendered discourse of technology and a spatial discourse around inside/outside contributed to the gender division of labour in this organization; however, the naturalization of gender disguised and legitimized inequality between men and women in the company. see jieyu liu, “white collar workers: gender and class politics in an urban organization,” in middle class china: identity and behaviour edited by chen minglu and david goodman (cheltenham, uk and northampton, ma, usa: edward elgar ), pp. - . see also ahu tatli, mustafa bilgehan ozturk and hong seng woo, “individualization and marketization of responsibility for gender inequality: the case of female managers in china,” human resource management : - . tatli, ozturk and woo find similarly that the company management tends to attribute the unequal career path for men and women in their organization to commercial-only focus of the organization or obscure it under individual choices of women managers rather than to gender discrimination. all the names have been changed in order to protect the anonymity of the interviewees. in my study, i did not find the majority of the professional men i encountered fit with the ‘metrosexual’ image presented by white-collar men in song and hird’s study. the difference between jieyu liu soas university of london my finding and their conclusion may be attributed to the research design: mine was in an organizational setting where i could observe how men interacted with women while their study was primarily drawing upon interviews with men only. see song and hird, men and masculinities in contemporary china , p. . r. w. connell, ‘men and globalization’, men and masculinities, ( ): - . p. l.h.m. ling, ‘sex machine: global hypermasculinity and the images of asian women in modernity’, positions: east asia critiques, ( ): - . p. harriet zurndorfer, “polygamy and masculinity in china: past and present." changing chinese masculinities: from imperial pillars of state to global real men. ed. kam louie. (hong kong: hong kong university press, ). - . i did not witness men of a lower institutional rank make sexually referenced jokes toward xiang zhang. gibson burrell ( ) “the organization of pleasure,” in mats alvesson and hugh willmott, eds., critical management (london: sage, ), - . katie r. sullivan, “with(out) pleasure: desexualization, gender and sexuality at work,” organization ( ): - . kari lerum, “sexuality, power, and camaraderie in service work,” gender and society ( ): – . christine l. williams, patti a. giuffre, and kirsten dellinger, “sexuality in the workplace: organizational control, sexual harassment, and the pursuit of pleasure,” annual review of sociology ( ): – . silvia gherardi ( ) gender, symbolism, and organizational cultures (london: sage, ) in a group setting, such as the company management meetings, another implicit function of men’s sexual jokes was to use women as a prompt for men to interact with men. for example, general manager wang appeared enjoying and indifferent to xiao zhang’s silence, which implied that the audience of his joke was really other men. this confirms zurndorfer’s observation that homosocial relations with other men remains a core part of chinese masculinity in the past and the present. harriet zurndorfer, “polygamy and masculinity in china: past and present." changing chinese masculinities: from imperial pillars of state to global real men. ed. kam louie. (hong kong: hong kong university press, ). - . the issue of sexual harassment at work has only recently been openly acknowledged as a problem, and has not yet been formally recognized in labour legislation. thus there was no company policy or jieyu liu soas university of london procedure for dealing with sexual harassment see ding yu, “negotiating intimacies in an eroticized environment: xiaojies and south china entertainment business,” international journal of business anthropology, ( ): – ; zheng tiantian, red lights. there are similarities in gendered control between the chinese companies i studied and the japanese companies, for example, vertical segregation by gender and the paternalist culture. while suffering from structural discrimination, women in my study and the office ladies in japan both demonstrated agency and resistance in their own office setting via emotional means. see ogasawara yuko, office ladies and salaried men: power, gender and work in japanese companies (berkeley: university of california press ); aviad e. raz, emotions at work: normative control, organizations and culture in japan and america (cambridge, massachusetts and london: harvard university press ). however, ogasawara and raz did not touch upon the sexual politics in japanese companies. further, there is a key difference in the background between professional women (university educated with strong personal aspirations) in my study and japanese office ladies who were mostly graduates of two-year women’s junior colleges and socialized to look on the office as a station on the road to marriage. these urban highly educated chinese women’s unprecedented ambition in personal development cultivated by a child-centred atmosphere in the intergenerational family became an important drive for them in their negotiations at work and in marital life; see more discussions on women’s emotional resistance in my forthcoming book, jieyu liu, gender, sexuality and power in chinese companies: beauties at work (london and new york: palgrave ). see evans, women and sexuality in china, p. . catherine a. mackinnon feminism unmodified massachusetts: harvard university press, ), pp. - . nussbaum, “objectification”. see zurndorfer, “men, women, money and morality.” p. see zurndorfer, “men, women, money and morality.”pp. - . s xjra .. why beauty matters george levine for those of us for whom “literary darwinism,” which bases its “scien-tific” approach to literary criticism on evolutionary psychology, has seemed an intellectual disaster, but who continue to believe that it is important to incorporate science cooperatively into our study of litera- ture; for those who are concerned about how art and literature matter in a world so troubled and dangerous; for those convinced darwinians who find themselves skeptical about and uneasy with the mechanico- materialist version of darwinism that richard dawkins and daniel dennett have made popular; for those who find that the science they credit is yet inadequately attentive to women’s perspectives, richard prum’s the evolution of beauty offers a potentially marvelous option. a dis- tinguished ornithologist, prum has undertaken an enormously ambitious project, whose implications run from evolutionary biology to aesthetics. from the perspective of a very unscientific literary guy and a wannabe birder, i slightly distrust my enthusiasm for the book. but prum’s argu- ments are creatively provocative and brilliantly argued, even when they get rather iffily hypothetical; his ornithological studies are intrinsically fascinating, even to nonbirders, and at the same time they have poten- tially transformative implications. what he has to say, even if his infer- ences can and should be challenged, deserves the most serious engagement. from the perspective of science, prum’s arguments make a strong entry in growing resistance to the dominant paradigm of evolutionary biology (and its virtually exclusive assumption taken over by evolutionary psychology), that all evolutionary change is adaptive, and that it happens algorithmically, without agency, intention, or mind. from the perspective of the humanities, prum lays the groundwork for a potentially creative and liberating aesthetic theory. from the perspective of interdisciplinary scholarship, he suggests fresh ways for science, the arts, and the human- ities to talk creatively to each other. in addition, he reinforces a strong george levine is professor emeritus of english at rutgers university. he is the author of many books on victorian literature, culture, and science, among them: darwin and the novelists ( ), darwin loves you ( ), darwin the writer ( ), dying to know: narrative and scientific epistemology in victorian england ( ), and his edited volume, aesthetics and ideology ( ). victorian literature and culture, vol. , no. , pp. – . © cambridge university press . doi: . /s x https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core feminist program from within the framework of scientific study. prum’s insistence on the importance of history, with all its contingencies, in understanding the way things are now may be old news to humanists, but it has a particularly important resonance within the virtually atempo- ral mechanico-materialist system that much scientific study prioritizes. the evolutionary history on which prum sets out is an unusual one. it is not a history of adaptations leading to speciation, but a history of “beauty,” an “aesthetic” history. his unusual focus is on individual prefer- ences, on desires and pleasures and even intentions. “we need,” he says, “to embrace darwin’s aesthetic view of life and fully incorporate the pos- sibility of nonadaptive arbitrary aesthetic evolution by sexual selection.” victorianists will recognize that although this is not a book about victorian culture, the story it tells has victorian resonances. they should be pleased to note that a fundamental move in prum’s argument is the attempt to replace modern “darwinism,” taken as the fundamental assumption of evolutionary science, with a darwinism more in keeping with darwin’s complete theory. the book’s subtitle, “how darwin’s theory of mate choice shapes the animal world,” aggressively affirms the centrality of darwin’s idea of sexual selection against the dominant, but only selectively darwinian, view that natural selection does it all. prum impressively builds a case, out of darwin’s original formulations of sexual selection, that female aesthetic choice provides a better expla- nation than the traditional adaptationist one for many evolutionary changes, not least the evolution of humans away from their primate origins. into the mechanisms on which all serious biologists agree, plum inserts the scientifically dubious elements of individual desire and inten- tion; in addition, he makes the case that evolutionary biology now is largely conducted from a male perspective. without challenging the importance of natural selection, he argues for a shift of perspective that would allow for other evolutionary forces—most particularly, female choice. reading the book for its wondrous study of birds and its chal- lenge to evolutionary psychology, i was startled to realize that i was read- ing also a fresh and singularly strong argument for feminism. prum’s work, from the perspective of a scientist, arrives at similar conclusions, working with similar darwinian ideas, that elizabeth grosz develops in a series of important books that courageously and importantly reconnect the biological and material with important cultural projects like femi- nism, despite the long history of misuse of such material for racist and sexist cultural projects. vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core the idea of “the evolution of beauty” might be said to have its begin- nings in the late eighteenth century, particularly in the work of erasmus darwin, charles’s famous grandfather, but later most fully among the victorians: first, in darwin’s focus in the descent of man on “mate choice,” and then in the disagreements that followed between darwin and a. r. wallace about sexual selection. for darwin, sexual selection was a hard-earned idea that grew from his deeply felt realization that the extravagances of some natural phenomena required an explanation for which his central theory of natural selection wouldn’t work. the intensity of the problem as he experienced it is implied in what he famously wrote to asa gray in : “the sight of a feather in a peacock’s tail, whenever i gaze at it, makes me sick.” while darwin found a nonadaptationist explanation for that feather, wallace, after years of debate in correspon- dence with darwin, did not; and wallace became a key figure in the sci- entific rejection of sexual selection that endured well into the twentieth century. wallace also famously veered off from darwin by arguing, almost in anticipation of current theories of intelligent design, that the enor- mous complexity of the human mind and brain (he uses mathematics as an example) is evidence that natural selection could not explain the development of mind. his rejection of sexual selection had longer-term consequences for science. today’s evolutionary biology—though obviously not accepting wallace’s move to spiritualism and despite its usual designation as “neo-darwinian”—is on prum’s reading wallacean rather than darwinian. in his book, darwinism, wallace represents darwin as insisting that “all the fixed characters of organic beings have been devel- oped under the action of the law of utility.” wallace thinks of himself as darwinian because his book is, as he puts it in the preface, based on the argument that “all [emphasis mine] specific characters are (or once have been) either useful in themselves or correlated with useful characters” ( ). but sexual selection doesn’t work that way. tracing the evolution of beauty, prum shows how it evolves precisely as it was not useful, and yet important enough to influence speciation itself. prum and darwin insist on inutility as a force in the development of varieties and species. darwin needed the theory of sexual selection not only to account for the peacock’s extravagant plumage, but also to account for racial divergence in a world he thought of as monogenetic: we all descend from the same beings, but each race, he believed, devel- oped distinct aesthetic preferences, preferences not necessarily linked to natural selection and utility. on the one hand, then, almost an aesthetic why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core relativist—every race’s perception of beauty is distinctive—darwin was, on the other hand, a victorian gentleman who was also, from our current perspective, both racist and sexist. victorian science shared these tendencies with darwin and because of them found it impossible to accept darwin’s theory of mate choice because it could not credit the female with as much power as the theory required. but it is hard to claim now that the theory is “forgotten,” as the subtitle of prum’s book suggests. r. a. fisher, with brilliant mathematical ingenuity, made the case for it against scientific consensus, first in and then in (it may be beside the point of the science, but fisher was also outspokenly racist and a supporter of eugenics). prum notes, however, that fisher’s ideas, which tended to confirm that sexual selec- tion works by showing just how it works, “would be mostly ignored for the next fifty years” ( ). now, as prum certainly does acknowledge, “all biologists embrace the fundamental concept of mate choice” ( ). what is controversial and fresh, then, in prum’s argument (aside from the wonderful ornithological studies he describes in the first half of the book) is his “embrace” of what he calls darwin’s aesthetic approach, making “beauty” (and the largely female choice that evokes it) central to evolutionary study, and deploying it as part of what seems a larger argument with important aesthetic and social implications, far from the racist traditions in which the idea was born. while prum rightly connects his own perspectives on sexual selec- tion with darwin’s, his embrace of the female role in speciation and evo- lutionary change takes him a long way, even from the darwin he is trying to reinstate. evelleen richards has convincingly demonstrated that darwin’s willingness, against the grain of his culture, to allow that females had the power of choice and thus to lead to important biological changes was not built on an affirmation of women’s strength, but on its reverse. the choice for extravagant inutility is what women do as they follow fash- ion trends. silly women simply haven’t got the kind of functional intelli- gence that would encourage them to choose the mate with the best chance of reproduction and survival. rather, they like fancy ornaments, subject to the whims of fashion. they are too coy and silly to choose the useful. prum regularly ignores darwin’s ingrained sexism, and makes the inutility of female choice one of the great strengths of the theory: inutility challenges the dominant darwinian theory of our time, just as darwin argued against wallace. in the face of the inutility of female mate choice, contemporary insistence that all evolutionary change is adaptive seems to leave too much out. vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core prum insists that darwin’s theory was forgotten in large part because — even against darwin’s own sense of the superiority of males to females—he so strongly focuses on female agency, female desire, female purpose. “we cannot doubt,” he writes in the descent of man, that, though led by instinct,” female birds ” know what they are about, and consciously exert their mental and bodily powers.” when he describes the female’s reaction to courting males, he says, “we cannot doubt” but that “the females, supposing that their mental capacity sufficed for the exertion of a choice, could select one out of several males.” darwin lets himself “suppose,” and in effect urges that we do as well. his language cedes to the realities he is discovering: “the exertion of some choice on the part of the female seems almost as general a law as the eagerness of the male.” certainly for the purposes of his argument, prum’s avoidance makes sense. although darwin was, in our current terms, victorianly sexist, his science, as jim enderby reminds us, took him where few of his contem- poraries were willing to go. the theory of sexual selection gives the female a strong role in evolution, while “several of his contemporaries —such as alfred russel wallace and st george mivart—rejected darwin’s proposal that female choice could have played any role in evo- lution because females were so notoriously fickle.” prum finds the same attitude more quietly embedded in modern evolutionary biology, and he contends that “darwin’s idea that the aesthetic evaluations invoked in mate choice among animals constitute an independent evolutionary force in nature is as radical today as it was when he proffered it nearly one hundred fifty years ago” ( ). part of what encourages trust in prum’s arguments is that he is not scientifically unorthodox when discussing the sheer mechanisms of sex- ual selection. in the blind watchmaker, for instance, dawkins describes those mechanisms, as they produce the extravagances of everything from feathers to vaginal tracts, which become so important to prum’s argument. dawkins also implicitly rejects the kind of doubts victorians had about the important role “weak” and “coy” females play in evolution- ary development. so, while it is not quite fair to say that darwin’s theory is now “forgotten,” it is fair to argue that it has been twisted in un-darwinian ways as it has been assimilated to natural selection. wallace had done that one hundred and fifty years ago. “female prefer- ence, says dawkins, is a genetically influenced variable just like any other” ( ). for prum, however, the most important point is that today’s dominant paradigm resists the idea that elaborate ornamentations “are why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core merely meaningless, arbitrary (albeit fabulous) results of co-evolutionary fashion” ( ). it was unease with the implication that his fickle females were subject to fashion that made darwin’s development of his theory so difficult; prum, relieved of the cultural pressures of victorian sexism, finds meaning in female mate choice. moving from prum’s language to my own, the strict adaptationist approach, which darwin also rejected, does not allow for art for art’s sake: a point i will develop later. it does not contemplate the free play of desire or the power of female self- interest. it does not emphasize sufficiently the possibility that sexual selection can at times win out over natural selection—well, at least up to a point. darwin first invokes sexual selection by distinguishing it from natural selection. “it acts,” says darwin, “in a less rigorous manner than natural selection. the latter produces its effects by the life or death at all ages of the more or less successful individuals,” while the former “rarely leads to death of the vanquished male.” in addition, while for natural selection there is “a limit to the amount of advantageous modification” possible, in sexual selection “there is no definite limit.” “sexual selec- tion,” darwin goes on, “depends on the success of certain individuals over others of the same sex in relation to the propagation of the species; whilst natural selection depends on the success of both sexes, at all ages, in relation to the general conditions of life.” which is simply to say that darwin imagined sexual selection not as a major footnote to natural selection, but as a process that works independently of it and is yet required for a fully coherent explanation of evolutionary change. female desire, however arbitrary, can at times win out. “the process of adaptation by natural selection,” prum insists from the start, “is not synon- ymous with evolution itself” ( ). prum focuses primarily on only one of the two major aspects of sex- ual selection to build his case. the male role is usually the one most attended to, with emphasis on the violent struggle of male against male for possession of the female, and thus the development of weapons like horns and talons. this struggle, darwin believed, makes of the male a more powerful, an even more intellectually powerful figure than the female, who “coyly” waits to be mastered. but he insists on the difference between the two forms of sexual selection: “in a multitude of cases the males which conquer other males, do not obtain possession of the females, independently of choice on the part of the latter.” prum’s book builds on the second aspect, “mate choice,” in which the female chooses among males and thus plays the dominant role. here, the vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core male’s superior physical powers are not the essential element and often play no role at all in mating. the nausea darwin felt at the sight of the peacock’s feather was, of course, caused by how impossible he thought it would be to account for it by way of natural selection. sexual selection became his way of account- ing for it. to clarify the problem, let us look briefly at prum’s ground- breaking work on the color of dinosaurs. after studying closely a raptor-like feathered dinosaur (discovered in china in the last century), prum came to realize that “the evolution of aesthetic plumage ornaments originated not within birds but way back in terrestrial theropod dino- saurs. the dinosaurs co-evolved to be beautiful—beautiful to them- selves—long before one exceptional lineage of dinosaurs evolved to become flying birds” ( – ). that little parenthetical “beautiful to themselves” is loaded. simple as it seems, it makes a major move to undercut the idea that speciation is entirely or even dominantly always the result of the adaptation seized upon by natural selection, or survival of the fittest. rather, “the evolution of beauty contributed to the evolu- tion of feathers themselves” ( ). not natural selection. originating as simple tubes on dinosaurs, feathers evolved with “downy tufts” and eventually into the “planar” forms that make such glo- rious canvases for color and are familiar to us in birds. female dinosaurs, demanding beauty in the male, selected for developments in the feather that allowed it to display color. only later, after beauty had begun doing its job, did feathers save dinosaurs from absolute extinction by turning them into birds. color first, not flight. aesthetic pleasure, not utility. the planar feathering that, eventually and luckily for us, developed into feathers that enabled flight was not an adaptation for flight. the won- derful irony here is that a desire for the beautiful divorced entirely from any useful purpose—what our practical-minded culture is trying to defund—saved dinosaurs from absolute extinction by allowing them to transform into birds. for evolutionary biologists following in wallace’s tradition, the idea that something other than adaptive fitness drives evolutionary change has been particularly difficult. there is still, apparently, disagreement in the field about whether beauty “means” something other than what it is, and thus can be assimilated to the adaptationist model. many biol- ogists believe that the beauty of the male, often extravagant and danger- ous to the male, “signals”—and “honestly signals”—reproductive fitness. the minority, to which prum belongs, believes that while “adaptive mate choice can occur” it “is probably rather rare.” these astonishing why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core ornaments “are merely meaningless, arbitrary (albeit fabulous) results of co-evolutionary fashion” ( ). a poem, a peacock’s feather, should not mean, but be. just as dollar bills have been detached from the “gold stan- dard” for which they were originally promissory notes, prum explains, beauty was detached from what it honestly signaled. the miser wants the dollar bills and does not worry about fort knox. the female wants the color and manages without any motive but her own pleasure to choose. the same thing can hold for humans. while neo-darwinist explana- tions imply that “there must be something of greater value in sexual attraction beyond mere sexual attraction” ( )—the theory of “honest signaling”—the evidence is that there is no relationship between body shape and fertility. prum cites a mathematical study by two biologists that has “documented that cultural mating preferences can create feed- back loops that result in the evolutionary elaboration of certain traits that are deemed desirable but have no survival or fecundity value—only aesthetic value” ( ). sexual attraction is sexual attraction—art for art sake, beauty for beauty’s sake, pleasure for pleasure’s sake. as prum neatly puts it, establishing a key phrase for his whole argu- ment, “beauty happens.” released from the gold standard, the dollar’s value is entirely a matter of agreement, a social construct, and everyone wants it. released from the utility it theoretically signaled, beauty becomes also a social construct: an agreement of both parties that the prettier the better—according to their lights. the resonance of this idea for aesthetic theory and criticism is strong and clear and remarkably in harmony with much extremely unscientific aesthetic theorizing of recent years. prum offers many examples of bird behavior and development that illustrate this sort of nonadaptive exchange. to make its mating “call,” for one remarkable instance, the club-winged manakin rubs its wing feath- ers together at a very high frequency, but to produce the sound the wing bones can not be hollow. yet hollowness seems a condition for bird flight and is characteristic of all other manakins. the club-winged fly less well than their cousins because, prum tells us, their ulnas “are four times wider and three times larger in volume . . .there is nothing else like it in any other bird in the world” ( ). but, then, of course, no other birds produce such sexy wing sounds. the beauty of the club-winged manakin’s “song” has a history. it is a physiological evolution different from that of all the other manakins, who are otherwise closely related, and it evolved very clearly from mate vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core choice, the female’s desire for the beautiful. to win mates, this manakin degenerated in fitness; it evolved “a decrease in overall survival capacity” ( ) under the pressure of female desire. the club wings are inherited by both male and female, but so too is the desire for them. this inheri- tance across both sexes assures a cascade of beauty-oriented changes: from generation to generation females get pickier and pickier; offspring inherit larger and stronger bones to make the music that will satisfy. in the pursuit of pleasure, it all becomes extravagantly useless and a sepa- rate species is born. de gustibus non est disputandum. beauty is not truth; it signifies “nothing but itself” ( ). in this whirling, self-reinforcing, aesthetically inspired dance, the female seeks the sound; the male body shapes itself to the female’s pleasure. the evolution of beauty entails a remarkable amount of free play. the idea of the aesthetic as a social contract is not the only impor- tant inference prum draws from the evolutionary engagement (and con- test) of female and male. along with attraction, mating includes a power struggle, the stronger male trying to impose himself on the less powerful female. in a chapter on duck sex, prum describes the extraordinary behaviors and physiological changes among males in mating season, all in response to choosy female ducks who are choosy “because they can be” ( ). this study is one of the few the book discusses that wasn’t con- ducted by prum and his team, but it dazzlingly confirms his larger argu- ments. most interesting for prum’s point, and more distressing for anyone who sentimentalizes ducks, is the behavior of “puddle ducks,” the drakes of which regularly rape the females. prum complains about ornithologists’ decision to call bird rape “forced copulation.” he wants, rather, to emphasize the “violent, ugly, dangerous, and even deadly” nature of sex among these ducks to make clear that it happens against the wills of the females. recognition of the female perspective here becomes essential. the cost of duck rape is not only direct damage to the female’s well-being, but indirect genetic loss: the females and the spe- cies suffer because successful rape not only lowers the number of avail- able females, but also diminishes the chances the offspring will inherit the traits—the “beauty”—that the females prefer. among “puddle ducks,” as prum calls them, the two modes of sexual selection are in contest: the male’s combat for power and dominance, the female’s desire for the beautiful. to overcome the resistance of the female, the males have developed long penises, sometimes longer than their own bodies. to counter, the female has developed a long sinuous vaginal tract with “thickened, convoluted walls . . . wrapped in a mass why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core of fibrous tissue”; “the longer and twistier the penis, the more complex the vaginal tract, full of nooks and crannies” ( ). prum and his team have discovered that though percent of the puddle ducks’ sexual rela- tions are coerced, “only – percent of the young in the nest are sired by a male who is not the chosen partner of the female.” the length and the nooks and crannies “are actually incredibly effective at preventing fertil- ization by force” ( ). in the end, the female carries almost exclusively the young of the male of her dreams, the most aesthetically satisfying of her courtiers: by being overwhelmingly successful at bottling up the penis during forced intromission, and preventing the vast majority of attempts at forced fertiliza- tions, female ducks have managed to maintain the advantage of this sexual arms race. even in the face of persistent sexual violence, female ducks have been able to assert and advance their sexual autonomy—their individual freedom to control paternity through their own mate choices. . .female mate choice continues to predominate. . . .beauty continues to thrive even in the face of persistent violent attempts to subvert the freedom of mate choice that creates it. ( ) although females cannot “evolve to assert power over others in respect to sexual violence,” they can “evolve to assert their own freedom of choice. . . . males evolve weapons of control . . . females are merely coevolving defenses that create opportunity for choice. it’s not a fair fight,” prum concludes; “however, as ducks show, female sexual auton- omy can still win” ( ). if nothing else, these remarkable stories of bird mating and evolution build a strong case: the grim story of the mind- less demands of natural selection for fitness, on matters of life and death, as darwin notes, must take one step to the side. natural selection cannot explain it all; room must be made for beauty, and thus for desire and intention and purpose. * there is yet another way in which current dominant scientific assumptions are simply not adequate to the realities of the natural world. darwin’s theory has been taken to imply that nature provides no “agency” for the enormous evolutionary changes through which it moves across geological time. what happens in evolution happens algo- rithmically: no mind directs it, no desire impels it. daniel dennett argues influentially that “life on earth has been generated over billions of years in a single branching tree—the tree of life—by one algorithmic process or another.” and he defines algorithm as working on three fundamen- tal conditions—first, “substrate neutrality,” which in effect means that vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core what matters is not the particular contingent content of the process, nor the causal powers that may drive them, but a simple logical structure which applies everywhere always. second, “underlying mindlessness”: however designed the outcome might seem to be, it is constructed of a series of steps that, if taken (and even an idiot might be able to take any one of those steps, as in a computer program), will—third—always produce the results, apparently designed or not ( ). algorithms func- tion independently of mind, of conscious direction, or of telos. although, as dennett shows, all of this has been subject to much dis- agreement and uncertainty, prum writes into an intellectual culture in which the “algorithmic” reading has largely triumphed. he mentions dennett only once, but in doing so he makes clear what his own program is: “i propose that darwin’s really dangerous idea is the concept of aes- thetic evolution by mate choice.” implicitly conceding that natural selec- tion works algorithmically, he yet claims that “natural selection can not be the only dynamic at work in evolution” ( ). in fact, his view of aes- thetic evolution is that it runs precisely counter to the algorithmic. unhinging sexual selection from reproductive fitness leads prum to his main point: “the inherently serendipitous and unpredictable nature of aesthetic evolutionary process” ( ). the ornithological studies that i have described are strong evidence that, as prum claims, birds “act as agents in their own evolution” ( ). the conclusion to his startling histories is even more startling, for his lan- guage seems almost lamarckian. he claims, for instance, that the history of the beauty of the manakin’s song is one strong example of how “ani- mals are aesthetic agents who play a role in their own evolution” ( ). prum never mentions lamarck, and he certainly rejects the lamarckian notion of the inheritance of acquired characteristics, but his language occasionally resembles lamarck’s, in suggesting that sexual selection reinserts into the evolutionary process the “intention” that dennett regards as a “skyhook”—it ain’t scientific. darwin’s own meta- phorical language, as particularly with the very active “natural selection,” often looks as though it is affirming agency even though he goes to great pains to deny it literally. lamarck was eliminated from the evolutionary canon in part because he believed in inheritance of acquired characteristics, but largely because this meant that he believed that organisms might “act as agents in their own evolution.” this idea of “agency” is subtly (and sotto voce) alive in prum’s argument—as it was in darwin’s—even though prum would certainly argue that while individu- als have intention, the broad transformations toward speciation are not at why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core all “intended” by an agent; they result from the normal unintentional developments within population genetics. samuel butler, in a long series of anti-darwinian books, culminating in evolution, old and new, argued that a theory that eliminates agency is radically flawed. prum’s birds, cer- tainly not acting with teleology in mind, yet act with a purposiveness it is hard to dismiss. but “for the current generation of biologists,” writes jessica riskin, “naturalism precludes treating agency as an elemental feature of the nat- ural world, or indeed as anything beyond an irresistibly compelling appearance.” whether prum’s experiments produce “an irresistibly compelling appearance” that is belied by the reality or not is for science ultimately to decide. in any case, riskin shows, in her magisterial book the restless clock, that it has been possible to be a pure mechanist and materialist and at the same time a scientist who believes in agency. thinkers as different as lamarck, darwin, dennett, and prum are all entirely naturalistic in their studies and arguments; all exclude from their nature studies any action from the “outside”—certainly any divine hand. the great irony that provides the structure of riskin’s careful and learned study of agency is that removal of agency from nature has its modern foundation not in science but in religion itself—most particu- larly, natural theology. that famous paleyan parable of the difference between the watch and the stone effectively turns nature into a machine without agency, and since there is no agency in nature, a god is required to explain its appearance. dennett’s algorithmic reading of nature is his substitute for paley’s god, since agency of some sort is essential to any adequate explanation of nature’s functioning. the running watch (inter- estingly, paley chooses a machine to make his point) cannot do it simply by virtue of its intrinsic material nature. ironically, then, dennett’s posi- tion is fundamentally a religious one. except he leaves god out. riskin points out that neo-darwinism developed, particularly in germany in the late nineteenth century, by making all scientific explana- tion dependent on a mechanical model, excluding not only any form of spirit, but any sort of internal agency. so lamarck’s explanation of evo- lutionary development, “according to which living forms developed grad- ually and contingently driven by their own inner agencies,” was rejected. neo-darwinians “reject the idea that intrinsic agencies operate in nature” ( ), and thus also reject darwin’s endorsement of lamarck’s view “that the ‘habits,’ ‘ways of life,’ and circumstances of animals very gradually shaped their organs” ( ). vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core the problem of agency looms over all naturalistic explanation. so prum’s argument is doing something extraordinary in telling us that mate choice is an “intrinsic agency operating in nature.” yet he is simply building on darwin’s own ideas: “it is impossible to doubt,” says darwin of birds, in a sequence that constantly evokes human language for beauty, “that the females admire the beauty of their male counter- parts.” “the taste for the beautiful,” says darwin, comfortably using lan- guage of intention, and desire, “is not of a special nature in the human mind.” riskin’s book is one major intervention in a developing concern about agency. being paleyan without god suggests that something is miss- ing in current scientific explanation, and j. scott turner’s purpose and desire: what makes something “alive” and why modern darwinism has failed to explain it, directly addresses the problem. he claims that such a position represents a serious “crisis” in biological thought. on the dennett/paley model, biology, turner claims, fails to make its own sub- ject, “life,” distinguishable from the inorganic. if “life” is a machine that can be understood in strictly chemical/physical terms, then how does it differ from paley’s stone? where is the distinction among the sciences? agreeing that “it seems hard to attribute striving and desire to anything living without getting into unscientific ways of thinking,” turner asks, “how do you experiment with desire?” in effect, although i have no idea whether he would accept turner’s analysis, prum’s ornithological studies might be read as just that, “experiments with desire.” mate choice is a choice—usually a female choice. it implies, at least anthropomorphi- cally speaking, a desire for the pleasurable—“taste,” as darwin puts it. prum’s female ducks work hard to protect their “taste.” prum does not avoid the implications of the verb “to choose,” as darwin had to do when he was challenged about the metaphorical implications of “selec- tion.” for, of course, selecting entails choosing, and choosing entails something that certainly has the appearance of consciousness. facing just this question of the appearance of agency (calling his language anthropomorphic suggests that the agency his language implies is mere appearance), darwin responds to criticism of his anthropomor- phism by offering in the fifth edition of the origin of species ( ) a description of natural selection that would satisfy dennett: it has been said that i speak of natural selection as an active power or deity; but who objects to any author speaking of the attraction of gravity as ruling the movements of the planets? . . . so again it is difficult to avoid personifying why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core the word nature; but i mean by nature, only the aggregate action and prod- uct of many natural laws, and by laws the sequence of events as ascertained by us. this is the language of algorithm, certainly central to dennett’s own version of darwin, and, if irregularly, it is a language darwin endorses. here, darwin urgently, almost angrily, withdraws agency from nature. it is telling that to make this point darwin uses for clarification “the movement of the planets,” in effect equating inorganic and organic nature. this is the darwin that prum ignores and dennett uses. from turner’s point of view, darwin fails here to distinguish life from nonlife. but darwin’s position in these problems is, as ever, ambiguous. he could not give up on his anthropomorphic metaphor, “natural selection,” and the language with which he otherwise describes “her” actions bursts with intention. as riskin discusses him, darwin remains somewhere in a limbo between the brute mechanism that relied on a distant god to get things moving, and another naturalist tradition, which saw the energy coming from an engine within. prum’s history of beauty very persuasively puts at least some agency back into evolutionary development just where darwin did when he dis- cussed sexual selection. “we now agree,” prum points out that ornament evolves because individuals have the capacity, and the freedom, to choose their mates, and they choose the mates whose ornaments they prefer. in the process of choosing what they like, choosers evolutionarily transform both the objects of their desires and the form of their own desires. it is a true evolutionary dance between beauty and desire” ( ). that “dance” is the basis of the aesthetic theory that prum is suggesting—beauty is, as it were, a negotiation between the desirer and the object desired; in a feed- back loop, desire transforms the object, which in turn reacts on the one who desires. as darwin says, there is no limit to how beautiful and strange and extravagant these developments might be. * the extent of prum’s daring becomes yet more overt when he notes that “in surprising ways . . .the evolutionary hypotheses i’ve outlined are strongly consistent with, and supportive of, contemporary gender theory” ( ), and then asks, “who could have imagined that evolutionary biol- ogy and queer theory could be on the same page about anything?” ( ). prum’s argument that “aesthetic evolution has great explanatory power” ( ) stretches across his science into large cultural issues, where his work might be taken as a strong, scientifically argued counterforce to vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core evolutionary psychology, as it is now practiced, and as evidence on funda- mental issues with which the humanities and social sciences are regularly engaged. the best way to see what’s wrong with literary darwinism is to see what’s wrong with the science that sustains it (although jonathan kramnick, working from the opposite direction, does a very strong job on it, and one that all literary scholars can profit from reading.) although he claims that much of his own work might be thought of as “evolutionary psychology,” since it concerns itself with the will and desires of animals in mate choice, prum laments that today’s evolutionary psy- chology “has a profound, constitutive, often fanatical commitment to the universal efficacy of adaptation by natural selection” ( ). as read- ers of literary darwinist criticism well know, “there is never any doubt what the conclusion of any evolutionary psychology [or therefore, i would add, literary darwinist] study will be” ( ). total adaptationism implies that all art, all culture, must be understood in terms of utility. the negative force of prum’s arguments, against the bad science of evolutionary psychology, as he sees it, and against its founding thesis, the universality of adaptation for fitness, seems to me very powerful. but as it extends from birds to the human, prum’s book becomes more problem- atic. no doubt his arguments are vulnerable, and one important review has already suggested that his claims—or at least the inferences he makes from his studies—are excessive: “the experience of seeing evi- dence of your favorite theory everywhere is prevalent among scientists,” the reviewer half mockingly complains. but by the time we arrive at the chapter called “human beauty happens too,” prum has, from my point of view, earned the right to what he confesses are only “specula- tions” that need to be “tested and analyzed” before they can be dismissed. once again, the argument begins with a rejection of neo-darwinist orientations: the “dominant view of hominin evolution as an interplay between male-male competition and adaptive, ecological natural selec- tion is insufficient to explain the key innovations that have occurred in the evolution of human cognitive, social, and cultural complexity” ( ). that view, prum claims, has diverted attention from the real prob- lems, which can best be recognized through an evolutionary history that attempts to account for our separation from our primate cousins. his alternative view is that “women’s pursuit of pleasure is at the very heart of the evolution of human beauty and sexuality” (just as, he has forcefully shown, female choice is at the very heart of much bird beauty and sexual- ity). the aesthetic history for which he is asking takes “pleasure as the why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core central, organizing force in mate choice, and mate choice as a major dynamic in evolutionary change” ( ), and as the primary force separat- ing us from our primate cousins. that case, which prum made about birds, he tests out again about women. we cultural studies types have long been used to thinking about the “male gaze,” which turns women into objects. prum argues that evolutionary psychology, even in its psychological experiments, reifies “the male gaze as an adaptation,” and has thus enshrined sexist bias in human evolutionary biology and notably failed to explain the mate preferences of the other half of the species” ( ). attending to that other half, prum rereads our break with other primates and every- thing from the unusual anatomy and large size of the penis (in compar- ison with other primates) to cultural variations in physiognomy and perceptions of beauty, and to the abundance of sexual practices, includ- ing homosexuality. so that, as with birds, the inutility of the aesthetic and the aesthetic drive accounts for a great deal in species development. “what is it that you women want?” is a famous grumpy male response to feminism. prum builds much of his argument in answering that ques- tion and offers a hypothetical but strongly explanatory account of our split with primates. simian social organization tends to inhibit change, since, for the most part, primates establish groups with a macho leader who prohibits other males from having sex with any females, and who will often kill the young who have been sired by a former leader. “viewed through the lens of human biology,” prum tells us, “the average male baboon, gorilla, or chimpanzee is an infanticidal maniac” ( ). males in these primate organizations leave the young to their mothers, who expend enormous energy on them, and then often find that energy wasted by male violence. as primates, we lowered the degree of violence that sustained a community: “the evolutionary mechanism for lowered male aggression, cooperative social temperament, and social intelligence . . .proceeded not by natural selection but by aesthetic sexual selection through female mate choice. ( )” the efforts in evolutionary biology to regard “beauty” as an honest signal of fitness once again makes beauty “mean” something. but human beauty “means” fitness no more than bird beauty does. both males and females—unlike most primates and other animals—make “mate choices.” sexual behavior across cultures varies as wildly as lan- guages and customs, and the “big challenge is to understand how our biological history and our cultural history interact to create the various expressions of human sexuality” ( ). prum notes that human males, vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core unlike most primates who “pursue every sexual liaison available to them,” are quite picky, in part because men make much larger “parental invest- ments” in their offspring than other primate males do. the neo-darwinist explanation of feminine beauty is that ample breasts and hips are not only beautiful but also biologically right for reproduction; yet, as prum points out, primate breasts only become prominent in breeding season. the permanent breasts of human females can be explained in the same ways as the peacock’s feathers, and long, crooked vaginal tracts, and club wings: so, too, the larger penises of human males (primates have very small ones, and so much for horny king kong). all, in prum’s theory, are effects of aesthetic agency in mate choice. everywhere, prum argues for (and produces evidence for) the irra- tionality of aesthetic evolution, the free wild arbitrariness of mate choice, and of the beautiful. he insists—consistent with riskin’s representation of the history of naturalist thought—that neo-darwinist thinking repre- sents the world as entirely “rational,” functioning always in the direction of adaptation, meaning. prum reinserts irrationality into evolutionary his- tory by not taking beauty as a signal, certainly not a signal of fitness, by reinserting agency and taking seriously will and desire. he claims that recognizing the irrationality allows for a better understanding of evolution historically and of current cultural practices as well. on this account, mate choice, both male and female, has produced the human species out of the world of primates, largely by satisfying female desires and female needs. prum reexamines neo-darwinist expla- nations of human qualities in a wide range of areas, everywhere from penis size, to female orgasm, to “decrease in the difference in body mass between the sexes,” to reduction of the size of male canine teeth, to male investment in the young. each of these changes satisfies what seem like female needs and desires (the question of whether penis size and scrotum are particularly attractive to women, as prum suggests, i leave open). humans “make more substantial reproductive investments. . . .resources, time, and energy to the protection, care, feeding and social- ization of their offspring” ( ). all of these suggest a widespread dimin- ishment of male aggression in the human split from primates. they also seem to be nonadaptive even as they satisfy female needs and desires. again, orgasmic female pleasure seems a particularly human trait. prum’s attempt to show how the most apparently nonadaptive phe- nomena can be understood better through the “beauty happens” the- ory, leads him to the chapter, “the queering of homo sapiens,” on homosexuality. the phenomenon has the same status within the theory why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core of natural selection as the peacock feather that upset darwin: how could it possibly be related to reproductive success and fitness? sexual behavior, prum points out, need not be understood in terms of sexual identity. that idea is not even two hundred years old, and sexuality is sexuality in whatever form it might take. “diversity of sexual practices is a pro- foundly human characteristic that must be accounted for,” says prum, but homosexuality is not a “conundrum” ( ). the wild freedom of sex- ual practices among humans (again, distinguishing us from other pri- mates) has always included sexual activity with no effect on reproduction. this is yet another instance in which aesthetic evolution is not connected to adaptiveness. it becomes a conundrum only if one is committed to the total adaptationist theory. consistent with its approach to all evolutionary phenomena, neo-darwinism attempts to transform the phenomenon into an adaptive one and has thus come up with the “helpful uncle” theory. the nonpro- ducing male contributes in the long run to overall fitness by helping busy moms and dads raise their children. prum’s speculation—very much a speculation—is, however, this: homosexuality “might have evolved through female mate choice as a mechanism to advance female sexual autonomy and to reduce sexual conflict over fertilization and parental care. according to the aesthetic hypothesis, the existence of same-sex behavior in humans is another evolutionary response to the persistent primate problem of sexual coercion” ( ). once again, female choice, female interest, becomes the explanatory hypothesis. granted, the evi- dence is thin, maybe no better than the “helpful uncle” theory, but it is at least not (yet) contradicted by the evidence and it entirely normal- izes a phenomenon that has historically been taken as an anomaly and would otherwise be taken as a “conundrum”—at best. but then one last big question, one that prum himself recognizes. if it is the case that “female sexual autonomy played a critical role in the evolution of human sexuality and reproduction,” if it was “a critical factor in the evolution of humanity itself,” why are women in human culture so consistently made secondary? why is violence against women almost a norm of human cultures? why in is a “#metoo” campaign even nec- essary? the fact seems strong evidence against the triumphal female-oriented aesthetic history prum has outlined. but prum has an explanation, one that further opens the way to cultural and gender stud- ies. first, males too have evolved in that other mode of sexual selection, and have “evolved mechanisms to advance their capacity for sexual coer- cion and violence” ( ). given male physical strength, in the struggle vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core between male and female “it is not a fair fight.” second, and here is another point at which prum’s speculative science emerges on the same page as gender studies and feminism: “subsequent evolution of human culture has resulted in the emergence of new cultural mechanisms of sexual conflict. . . .cultural ideologies of male power, sexual domina- tion, and social hierarchy—that is, patriarchy—developed to reassert male control over fertilization, reproduction and parental investment as countermeasures to the evolutionary expansion of female sexual autonomy. the biological war is now being conducted through the mechanisms of culture” ( ). what matters most here is the expulsion from the discussion of the idea that the current state of male domination is somehow a biologically implanted, evolutionary necessity, against which no cultural resistance, like the current “#metoo” movement, can ultimately have any power. prum believes that there remains the possibil- ity of women “fully consolidating the previous evolutionary gains in sex- ual autonomy” ( ). prum’s book is so heartening not because he has conclusively made his case. the speculative nature of so much of his large conclusion leaves much in doubt. there is, in addition, always the danger that he, like the eugenicists he attacks, is biologizing cultural phenomena, a practice with an unpleasant victorian and post-victorian history. but one cannot not take biology into account in this very material world. and prum has made a fascinating and forceful case for the idea that it is possible to find other and more fully satisfying explanations of current biological and cultural phenomena, and that serious scientific investigation, freed from the full adaptationist dogma, is not doomed to the same predictable conclusions that evolutionary psychology had been imposing on us. perhaps pie in the sky. but the aesthetic evolutionary history that prum lays out through his startling and wonderful chapters on bird life, fol- lowed by his strong speculations on the causes of the human split from primates, makes sense. it is certainly a workable hypothesis. to this lay critic, it is refreshingly plausible. i hope it is right. whether or not the larger case holds up, however, the “beauty happens” theory provokes fresh thinking, not only about scientific method and perspective, not only about cultural phenomena in general, but specifically about art. it suggests a world that has evolved virtually on the principle of “art for art’s sake.” free arbitrary pursuit of the beautiful to its wildest possible extravagances may be recognized as no mere self- indulgence after all, but as a condition of change and growth, a prod to creativity and the new. if prum is right, we humanists might infer why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core that the “beauty” we study—often with a sense of guilt for devoting such energy to art rather than to the harsh realities of the world that science and social science and the daily newspaper constantly reveal to us—is not a diversion from harsh reality but is integral to it and evolving as the world evolves. making huge inferences from prum’s already large ones, beginning with recognition that beauty is not marginal but central to evo- lutionary history and life itself, we can feel reassured of the significance of the humanities and in our own professional engagement with the beautiful, though it gets us no degrees in business and economics, and may seem a long way from the immanent moral and humanitarian crises that confront everyone, everywhere, every day. prum’s theory of art as the coevolutionary development of funda- mentally arbitrary likings and attractions—perceiver affecting perceived, perceived affecting perceiver—is a useful tool for understanding (and valuing) cultural difference. it foregrounds individual free-ranging “taste,” explains not by reduction to algorithm but by affirming individ- ual, contingently provoked desire. despite science’s long, honorable, necessary commitment to an objectivity and factuality that excludes pur- pose, will, and intention, evolutionary history, on prum’s account, can only be fully understood if it allows for the power of pleasure and includes the history of beauty. theorists, critics, scholars, feeling the pressures of the need to mean and to matter, to be useful in some way in relation to the most pressing concerns of culture and society, often wonder (usually privately) whether it makes sense spending one’s life criticizing novels and poetry while the world is burning. (among us victorianists, one senses this feeling in the recent manifesto and activities of the v group.) some richer sense of the importance of what is not “useful” might help. it is, on prum’s account, just in individual desire, in the disregard of the merely useful, that sexual selection directs change to new forms of beauty and of life. prum is working now on a whole theory of aesthetics, one that makes any defined universal elements in art chimerical. in an essay strictly about aesthetics, prum argues that “beauty is not dependent on meaning to exist.” art is always in process, always a matter of desire (unhinged from “meaning” and “utility”—though any work of art may itself be meaningful and useful in some way). its variations are limited only by the range of possible human desires. here, heuristically, is prum’s sum- mary point: “once we understand that all art is the result of a coevolutionary historical process between audience and artist—a coevolutionary dance between display and desire, expression and taste— vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core we must expand our conception of what art is and can be. . . . being an artwork means being the product of a historical process of aesthetic coevolution. in other words, art is a form of communication that coevolves with its own evaluation.” like club-winged manakins mating. so prum takes his ornithology to quite daring hypotheses that it will well repay literary scholars to consider. but i want to conclude by daring a bit too, with an analogy: darwin’s origin is also pervasively hypothetical. the strategy was not so much to prove that evolution by natural selection happened as to demonstrate that the hypothesis that it did happen, and largely by means of natural selection, fits better what we certainly know about nature than any other hypothesis out there. darwin knew he couldn’t prove it in , but he wanted minimally to show that his expla- nation of evolution fit the existing facts better than the dominant one he was trying to displace. the origin too laid out its hypotheses as a plan, a framework for future investigation: “i look with confidence to the future, to young and rising naturalists, who will be able to view both sides of the question with impartiality.” “in the distant future,” darwin wishfully affirms, “i see open fields for far more important researches.” i make no claim that prum’s work has darwin’s power or significance. as i write, i think of endless objections and questions and doubts. but the evolution of beauty has something of the ambition of the origin, some- thing of its beauty and factual density, and much of its hypothetical argu- mentative structure. like the origin, it is based on dazzling and important field work, making large claims that run against the grain of the day’s dominant scientific paradigm. like the origin, those inferences have implications that resonate through a wide variety of fields of study. like the origin, it still must be taken as a heuristic, a provocation to fur- ther work. prum chose this popular mode of expounding his large argu- ment just because he wanted to cultivate the field for those “young and rising naturalists” who might enter their advanced work more disposed to look at evolution from the perspective of “beauty happens.” i am myself ready to be unconvinced, but not before prum’s arguments are shown to be inconsistent with what’s out there in nature and with what my own experience has taught me that literature does. notes . prum, the evolution of beauty, . all subsequent references to this edition are noted parenthetically within the text. why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core . pearl brilmeyer has called my attention to the important work of elizabeth grosz, which anticipates much of prum’s argument, emphasizing in particular the distinction between natural selection and sexual selection: becoming undone. see particularly the chapter “art and the animal.” and see also the nick of time. . the correspondence of charles darwin, : . . wallace, darwinism, . . richards, darwin and the making, chapter . . darwin, descent, : . . darwin, : . . darwin, : . . endersby, “darwin on generation,” . . dawkins, watchmaker, . . darwin, descent, : . . darwin, : . . darwin, : . . dennett, darwin’s dangerous idea, . . riskin, the restless clock, . . darwin, : . . darwin, : . . turner, purpose and desire. . darwin, origin, . . see my discussion of this issue in darwin the writer. for a fuller discus- sion, see richards, “darwin’s theory of natural selection and its moral purpose,” . . riskin, the restless clock, . . kramnick, “against literary darwinism.” . flannery, “objectifying male birds.” . prum, “coevolutionary aesthetics,” . . prum, evolution of beauty, . . darwin, origin, . . darwin, origin, . works cited darwin, charles. the correspondence of charles darwin, . vol. . edited by frederick burkhardt et al. cambridge: cambridge university press, . ———. on the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life ( ). cambridge, ma.: harvard university press, . vlc • vol. , no. https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core ———. the descent of man, and selection in relation to sex ( ). princeton: princeton university press, . dawkins, richard. the blind watchmaker: why the evidence of evolution reveals a universe without design. new york: w. w norton, . dennett, daniel. darwin’s dangerous idea: evolution and the meaning of life. new york: simon & schuster, . endersby, jim. “darwin on generation, pangenesis, and sexual selection,” in the cambridge companion to darwin. nd edition. cambridge: cambridge university press, . flannery, tim. “objectifying male birds.” new york review of books, december , , – . grosz, elizabeth richard. becoming undone: darwinian reflections on life, politics, and art. durham: duke university press, . ———. the nick of time: politics, evolution, and the untimely. durham: duke university press, . kramnick, jonathan. “against literary darwinism.” critical inquiry , no. (winter ): – . levine, george. darwin the writer. oxford: oxford university press, . prum, richard. “coevolutionary aesthetics in human and biotic artworlds.” biology and philosophy, ( ) : – . ———. the evolution of beauty: how darwin’s forgotten theory of mate choice shapes the animal world and us. new york: doubleday, . richards, evelleen. darwin and the making of sexual selection. chicago: university of chicago press, . richards, robert. “darwin’s theory of natural selection and its moral purpose.” the cambridge companion to “the origin of species.” cambridge: cambridge university press, . riskin, jessica. the restless clock: a history of the centuries-long argument over what makes living things tick. chicago: university of chicago press, . turner, j. scott. purpose and desire: what makes something “alive” and why modern darwinism has failed to explain it. new york: harperone, . wallace, a. r. darwinism: an exposition of the theory of natural selection, with some of its applications ( ). london: macmillan, . why beauty matters https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core why beauty matters notes works cited jhp_beauty-science- -clean the beauty of science without the science of beauty kant and the rationalists on the aesthetics of cognition angela breitenbach (forthcoming in journal of the history of philosophy) abstract claims about the beauty of theories and explanations are often inspired by the platonic vision that beauty will lead us to truth. by contrast, kant’s aesthetics is commonly regarded as providing the most influential critique of this vision. in this paper i show that this popular contrast is mistaken in important respects. by examining kant’s views in comparison with those of his immediate contemporaries, a. g. baumgarten and g. f. meier, i show that the kantian position offers an important contender to the platonic ideal, namely, a conception of the beauty of science that is independent of the science of beauty. . introduction it is common to praise the beauty of theories, the elegance of proofs and the pleasing simplicity of explanations. we may admire, for example, the beauty of einstein’s theory of general relativity, the simplicity of darwin’s idea of natural selection, and the elegance of a geometrical proof of pythagoras’ theorem. aesthetic judgments such as these have much currency among scientists, and they are employed in the search for knowledge more widely. but while the use of aesthetic judgments in science is widespread, it is not uncontroversial. on one side, such judgments are often inspired by the platonic vision that beauty and truth are ultimately one. as henri poincaré saw it, science is the “disinterested pursuit of truth for its own beauty,” and it is the “intellectual beauty” of science “which gives certainty and strength to the intelligence.” perceiving beauty in science is, on this conception, simply another way of cognizing the true order of nature. experiencing the beauty of theories and explanations and knowing their truth are two perspectives on one and the same thing, the fundamental structure of reality. on the other side, by contrast, kant’s aesthetics is commonly regarded as the most influential critique of this vision, a vision that had also inspired many of kant’s rationalist contemporaries. kant construes aesthetic judgments as involving the free play of imagination and understanding, and hence as essentially distinct from determinate cognition. for this reason he dismisses the possibility of genuine intellectual beauty. his aesthetics has consequently been taken to support a skeptical approach to the idea of beauty in science, and aestheticians have offered kantian arguments against ascribing aesthetic merit to theories, proofs or explanations. i believe that this popular contrast between the platonic ideal and its kantian critique is mistaken in significant respects. most importantly, it obscures the positive alternative that emerges from kant’s engagement with the vision so aptly described by poincaré. on this alternative conception, aesthetic judgments do not themselves provide cognitive access to the truth, and determinate scientific claims do not on their own ground aesthetic pleasure. by contrast, science can be the object of aesthetic judgment if it allows for free reflection and an intimation of that which lies beyond what is strictly represented. sensible representations as well as theories and explanations can elicit such reflection if they are the products of creative intellectual activity. on the kantian account, it is these intellectual activities, broadly construed as a creative and open-ended pursuit, that make possible a distinctive aesthetic experience in science. my aim in this paper is to spell out and develop this alternative conception of the beauty of science. to do so, i begin by considering the views of kant’s immediate rationalist contemporaries, followers of leibniz and christian wolff, who were themselves treading in plato’s footsteps. i focus, specifically, on alexander gottlieb baumgarten, famous for giving aesthetics its name, and his student georg friedrich meier, a prolific writer, set on developing his teacher’s ideas (§ ). i concentrate on the two because they were particularly concerned to elaborate a rationalist aesthetics, and because kant was familiar with key writings of theirs and used their theory of aesthetics as a foil for his own account. in the subsequent section i examine why for kant, by contrast with the rationalists, the determinate claims of science are essentially distinct from the reflective judgments of beauty (§ ). as usual, examining the details of the historical contrast reveals that the arguments are more complex and the ideas more intertwined than the popular sketch suggests. the comparison brings to light, in particular, that kant’s casual dismissal of the beauty of science in the critique of judgment is crucially limited. in part disclaiming, in part advancing rationalist insights, kant’s account stands in a mixed relationship to that of his contemporaries. as i argue in the following two sections, his theory provides the resources for an aesthetics of science, broadly construed as a creative intellectual activity. more specifically, his position implies a conception of the aesthetics of scientific representations (§ ), and it offers the basis for a more general account including the aesthetics of scientific theories and explanations (§ ). i argue that this alternative conception can answer the challenge that science is too intellectual, and too conceptually determinate, to allow for the free reflection that grounds aesthetic pleasure on kant’s account. in fact, i suggest, the account exposes the close links between kant’s aesthetics and his theory of cognition, and thereby sheds light on the sensible dimension of the scientific search for truth. to be sure, kant does not explicitly develop this account himself. but it is one we can construct from the theoretical resources he lays out. nor does the proposed conception account for all judgments of beauty ever made about science. but it makes sense of a species of pleasure widely recognized as the appreciation of scientific beauty. the kantian account i propose thus offers a powerful contender to the platonic ideal by developing a conception of the beauty of science that is independent of the science of beauty (§ ). . rationalist connections how could the perception of beauty give us access to reality? it could if it were itself a form of the cognition of reality. this, in brief, is the idea behind baumgarten’s and meier’s aesthetics. following leibniz and wolff, they construe the perception of beauty in an object as the cognition of the object’s perfection, that is, of the internal unity and harmony of the parts within the object as a whole. more specifically, on their account, to perceive the beauty of an object is to have sensible cognition of its perfection; beauty is, in baumgarten’s words, “the perfection of an appearance” and ugliness its “imperfection.” baumgarten and meier stay within the leibnizian-wolffian framework in characterizing sensible cognition as a clear but confused representation of things, in contrast with clear and distinct rational cognition. as a form of sensible cognition, the perception of beauty thus consists in recognizing the object’s perfection, without achieving the distinct insight that only rational cognition makes possible. in appreciating the beauty of a mountain landscape, for example, i am aware of the unity and harmony of my perspective on the mountain range, the lake it encloses and the clear sky above, but i do not, thereby, prize apart the distinguishing features of shapes and colors, light and shadow, and perhaps smells and sounds, that make the landscape stand out. according to baumgarten and meier, it is the way in which clear and confused cognitions are achieved, furthermore, that accounts for the special phenomenal character of aesthetic experiences. in perceiving perfection through the senses, they argue, the lower cognitive powers are brought into harmony with one another, which is accompanied by a feeling of pleasure. the perception of beauty is thus a form of objective cognition which speaks to our passions and makes rational insight emotionally accessible. in meier’s words, it gives “flesh and blood” to the mere “skeleton” of the distinct insights of reason. this, in broad strokes, is baumgarten’s and meier’s cognitivist conception of beauty. one may object to this conception that not all sensible cognition of perfection is equally aesthetically pleasing. different attempts to represent the same mountain range—gerhard richter’s black and white painting, “gebirge,” compared with my own sketches, fondly but amateurishly remembering the scenery of a holiday hike—clearly have different aesthetic value. baumgarten and meier account for this thought by arguing that sensible cognition can itself be more or less perfect. what can be perfected is that feature which distinguishes sensible from rational cognition, its confused rather than distinct character. while distinctness is achieved by isolating the marks contained in a concept, the confused character of cognition increases as more and more marks are combined in a single representation. the perfection of rational cognition thus aims for abstraction, while aesthetic perfection is achieved by focusing on the specific and by illustration and exemplification. sensible representation is the more beautiful, on this conception, the more lively and truthful to the particularity of the object it represents the object’s perfection. this contrast between the more and less aesthetically perfect character of cognition accounts for the difference between gerhard richter’s art and my own attempts at drawing. it also explains, for example, the aesthetic difference between descartes’s dry and studied treatise on astronomy in his principes de la philosophie, whose sensible stimulation is limited to a few diagrams, and the literary presentation of the same theoretical content in bernard fontenelle’s entretiens sur la pluralité des mondes habités. instead of principles and proofs, set out in quasi-mathematical style, fontenelle explains the heliocentric model of the universe in the setting of a nocturnal dialogue between a philosopher and a marquise who wonder about the marquise’s garden gazing at the stars. fontenelle’s popular account of astronomical insights is detailed and illustrated by examples. on baumgarten and meier’s account, it is for this reason that fontenelle’s novel, while communicating the same scientific content as principes de la philosophie, is more beautiful than the less extensively clear diagrammatic representations of descartes. as meier puts it, it is the richer and more “lively” cognition that “exercises the powers of the mind and thereby touches on the soul.” baumgarten and meier thus regard judgments of beauty and cognitive insights as intimately connected. on their account, the experience of beauty is a form of cognition that, just like the more abstract insights of reason, lays bare the structure of reality, while at the same time, and unlike cognition from rational principles, giving rise to aesthetic pleasure. moreover, according to them, cognition can be perfected aesthetically as well as logically. it may be more or less beautiful just as it may be more or less conceptually distinct. it is this cognitive conception of aesthetics, which grounds the tight connection between aesthetics and science. on the one hand, we can have principles of beauty and, hence, a science of aesthetics. for we can determinately specify the features that ground aesthetic judgments, features of the object as well as of its representation. on the other hand, the cognitive insights of science can themselves be beautiful. achieved in the right way, namely, through the extensively clear representations of the senses, objective cognition is a source of aesthetic pleasure. as meier puts it, the beautiful sciences are not bound to any specific object of our cognition; rather they can be concerned with theological, philosophical, mathematical, juridical and medical matters etc. … they are concerned with the special way and manner of cognizing some thing. baumgarten’s and meier’s account thus makes room for the science of beauty as well as the beauty of science. the cognition of beauty is the subject of the science of aesthetics, while the insights of the sciences can be the objects of aesthetic judgments. . kantian divisions a difficulty with the rationalist account of beauty is that it seems overly intellectualist. construing the experience of beauty as a form of cognition, whether sensible or non-sensible, does not appear to capture what is so special about aesthetic appreciation, namely, its peculiar relation to the subject and her feeling of pleasure and displeasure. this, in brief, is the objection kant raises against baumgarten’s and meier’s identification of aesthetic judgment with the cognition of perfection. although the exact details of kant’s relation to the aesthetic theory of his rationalist predecessors are a matter of some controversy, two points of disagreement are clear. first, kant rejects the rationalists’ view that we can have access to the fundamental structures of reality either (distinctly) through reason or (confusedly) through the senses. on kant’s transcendental idealist account, cognition requires both intellect and sensibility, and it can give us insight only into appearances and not into the nature of things in themselves. second, kant denies that aesthetic judgment can be identified with the cognition of perfection, even once we have construed cognition along transcendental idealist lines. as he declares in the critique of judgment, [t]o grasp a regular, purposive structure [gebäude] with one’s faculty of cognition (whether the manner of representation be distinct or confused) is something entirely different from being conscious of this representation with the sensation of satisfaction. aesthetic judgments differ from ordinary cognition, kant argues, since they relate the representation of an object to the subject’s capacity of feeling. as he puts it, through aesthetic judgments the subject “feels itself as it is affected by the representation.” of course, on kant’s account, not any feeling of pleasure gives rise to aesthetic experience. a judgment is properly aesthetic only if the subject has reason to claim that others ought to feel the same. she makes a genuine aesthetic judgment only if she can impute the legitimacy of her feeling to everyone else. in the third critique, kant proposes to account for the peculiar nature of aesthetic judgments and their difference from ordinary cognition by his theory of the free play of the faculties. what is important about the intellectual activity involved in judgments of the beautiful, he argues, is that it conforms to the general conditions of cognitive judgment without in fact constituting determinate cognition. successful cognition depends on the work of the imagination, the capacity to combine the sensory manifold and to be aware of the resulting combination as a unity. it furthermore relies on the faculty of understanding, the conceptual capacity by means of which we make sense of the combined manifold as a unity of a specific sort. cognition consists in determinate judgments about sensory objects. aesthetic judgments significantly differ from determinate cognition thus construed. they are not constituted by the recognition that the object has such and such properties, but by a non- determining reflection in which we are aware of the object as suitable for understanding without, however, construing it as suitable to be understood in any one particular way. by reflecting on the imaginative synthesis in a manner that could in principle be brought under concepts, the judgment conforms with the general conditions of cognition while remaining conceptually indeterminate. it is this harmonious yet conceptually indeterminate interaction of imagination and understanding and the associated awareness of the object as fitting with our cognitive capacities that grounds aesthetic pleasure. kant characterizes the suitedness of the object for our intellectual faculties as a “purposiveness without a purpose,” that is, a purposiveness whose purpose is conceptually indeterminate. the objects of aesthetic appreciation are purposive, on kant’s account, not because they are conducive to realizing the subject’s particular end, for instance, that of finding the solution to an intellectual problem. instead, beautiful objects are purposive since, by reflecting on the form of such objects, our cognitive faculties are “unintentionally brought into accord with one another.” more specifically, since we do not become conscious of this fit by subsuming the object under determinate concepts, but through a feeling of pleasure, aesthetic judgment has a distinctive subjective character. moreover, since this pleasure is related to a harmony of capacities common to all, and not dependent on the satisfaction of any particular idiosyncratic desires, aesthetic pleasure can be imputed to all. this is why kant maintains that the free play of imagination and understanding is associated with a feeling that has universal validity. by contrast with baumgarten’s and meier’s aesthetics, on kant’s account, the experience of beauty is thus importantly unlike determinate cognition of the objective structures of reality.kant draws an important conclusion from this. “there is neither a science of the beautiful, only a critique, nor beautiful science, only beautiful art,” he maintains. the first half of this assertion follows directly from kant’s account of aesthetic judgment. there can be no science of the beautiful, since there are no rules to specify the features that make something beautiful, neither rules pertaining to the perfection of the object itself nor to its representation. aesthetics therefore cannot be a science but only a critique. it can investigate the cognitive faculties involved in aesthetic judgments, but not the features of an object that constitute its beauty. moreover, kant repudiates not only the conception of aesthetics as a science of beauty but also the possibility of a beautiful science. he claims that “if one were to ask in [such a science] for reasons and proofs one would be brushed aside with tasteful expressions (bonmots).” he suggests, in other words, that if there were a beautiful science, scientists would answer the quest for truth by an appeal to beauty. one might wonder, however, why scientists should not be able to give reasons and proofs that would also leave room for the free reflection of aesthetic judgment. why should it be impossible, as kant seems to suggest, to answer the quest for truth in a way that has aesthetic merit? in response one might suggest that for kant a beautiful science is an “unding”—an absurdity, or literally a non-entity—since something can be an object of aesthetic appreciation only if it is sensory. according to this suggestion, kant’s position entails that the purely reflective judgment which grounds the experience of beauty can have as its object only sensory manifolds but no conceptual claims. on this proposal, the synthesizing activity of the imagination would have to be directed at the bare sensory material, not at concepts, judgments or ideas. one might think, furthermore, that abstracting from all concepts in the case of theories or proofs would leave no manifold to be reflected upon, and would thus eradicate all possible candidates for aesthetic appreciation. a difficulty with this response, however, is that kant is more than happy to promote other entities as key examples of beauty that, just like scientific theories, deal with concepts and ideas. such entities include works of poetry and literature; and, indeed, he regards poetry as the highest form of beautiful art. kant can claim as much because he makes room for a second, related, conception of beauty according to which aesthetic judgments consist in reflections on particular representations of concepts and ideas. aesthetic judgments about poetry and literature, for example, rely on the free and harmonious interaction of the faculties. they do so, however, in engaging not with the bare sensory manifold but with conceptual representations. in contemplating poetry or literature, the imagination is thus free to reflect on an inexhaustible wealth of thoughts associated with the concepts and ideas expressed by the artwork, while being unconstrained by any particular conceptual interpretation. goethe’s erlkönig, for example, takes the form of a ballad that conveys the simple story of a father riding home with his sick son who hallucinates being assailed by the ‘erl-king’. the poem tells a simple story whose representation procures imaginative associations of supernatural powers, of fear and vulnerability, and of abuse and rape. on kant’s account, representations such as these make possible an inexhaustible wealth of thoughts that is not fully determined by the concepts underlying the story itself but nevertheless adequate as an expression of these concepts. as kant puts it, artworks “expand… the mind by setting the imagination free” and by connecting the representation of a concept with “a fullness of thought to which no linguistic expression is fully adequate.” works of art can thus represent concepts while allowing for conceptually unconstrained and inexhaustible reflection. they can do so, kant claims, because they are the product of genius, the original and exemplary capacity to create artistic expressions that go beyond the content of the concepts they represent, while nevertheless being adequate as expression of those concepts. as kant puts it, genius really consists in the happy relation, which no science can teach and no diligence learn, of finding ideas for a given concept on the one hand and on the other hitting upon the expression for these, through which the subjective disposition of the mind that is thereby produced, as an accompaniment of a concept, can be communicated to others. it is the representations of this original and exemplary capacity that, despite being the product of intention, leave room for judgments in which the harmony of our cognitive faculties can be appreciated, in kant’s earlier words, as “unintentional.” the expressions of concepts and judgments brought about by the capacity of genius leave room for the free play of the faculties and, hence, for aesthetic pleasure. kant thus accounts for judgments of beauty that involve reflection on conceptual representations. why, then, does he nevertheless maintain that there can be no beautiful science? and why does he add the further claim that genius is possible only in art but not “in the scientific sphere”? . scientific representations and aesthetic perfection in order to understand why kant proclaims that there can be no beautiful science, we must be clear about what the statement entails. i believe kant’s claim is much more limited than is commonly understood. kant’s statement is focused on science “as such,” that is, science in the strict sense as a “system of cognition,” consisting in systematically unified determinate judgments. there is no indication that kant is concerned with the scientific enterprise more widely construed, encompassing not only scientific claims such as theories and explanations but also scientific practices such as calculating and experimenting, modeling, representing and visualizing of data and, more broadly, theorizing. this suggests that, when kant maintains there can be no beautiful science, he makes the narrow claim that determinate cognitions cannot ground aesthetic pleasure. he does not thereby imply that aesthetic judgment has no place in our scientific endeavors more widely conceived. in accordance with this narrow reading, kant’s rejection of beautiful science follows straightforwardly from his repudiation of the other rationalist conviction, the principle that aesthetic judgment is a form of determinate cognition. since determinate judgments cannot ground aesthetic pleasure, on kant’s account, and since science in the strict sense consists in a system of determinate cognitions, science itself cannot ground aesthetic pleasure. kant’s contentious assertion that there is no beautiful science is thus a simple reformulation of his widely acknowledged view that aesthetic judgments are distinct from ordinary cognition. once kant’s rejection of beauty in science is interpreted in this strict sense, moreover, we can refocus the questions i raised in the previous section. even if the determinate cognitions of science do not themselves ground aesthetic pleasure, could aesthetic judgments not be a part of science more widely construed as a human activity? could we not find beauty, for example, in a science that includes the representations and practices of scientists? kant addresses the aesthetic dimension of cognition in his lectures on logic and anthropology. he is concerned there with baumgarten’s and meier’s distinction between the aesthetic and logical perfections of cognition. since kant’s logic lectures are oriented along meier’s logic textbook, auszüge aus der vernunftlehre, it is not surprising that kant discusses meier’s distinction there. what is more surprising is that, having rejected the rationalist claim that cognitive judgments can ground aesthetic pleasure, kant holds on to the rationalist distinction and claims that the representations of cognition can be more or less aesthetically valuable. in the lectures, kant associates the distinction between the aesthetic and the logical perfection of cognition with that between sensibility and understanding, and their representations, intuitions and concepts. one might therefore think that, for kant, the aesthetic perfection of cognition has nothing to do with beauty but, following the terminology of the transcendental aesthetic of the critique of pure reason, with sensory representation in general. on this reading, cognition can be perfected either with the aim of illustrating our concepts through sensory representations (versinnlichen), that is, in accordance with the first critique notion of aesthetics (henceforth, ‘aestheticsc ’), or with the aim of gaining conceptual insight, that is logically. while logical perfection aims at the complete clarification of concepts and conceptual relations, the goal of aestheticc perfection is “comprehensibility” (faßlichkeit), that is, the capacity of the significance of concepts to be grasped in concrete cases. aestheticc perfection is achieved, for instance, through the use of examples and illustrations as in the work of fontenelle. it concerns the “ease” and “liveliness” with which cognition is attained. construed in this way, maintaining baumgarten’s and meier’s distinction between two types of perfection is unproblematic for kant, since it does not concern his conception of beauty at all. by contrast with the rationalists, kant holds that cognition requires connection with sensibility, just as it requires conceptual recognition of the sensible. kant can thus coherently hold that both types of representation, intuitive and conceptual, or aestheticc and logical, are necessary for cognition. on this reading, what kant spells out by elaborating on the aestheticc perfection of cognition, are the empirical conditions of how sensible representation is achieved for creatures like us. both logical and aestheticc perfections can be regarded as perfections some instantiation of which is necessary for cognition. and yet this is not the end of the story. for, in other parts of the lectures, kant qualifies his conception of aestheticc perfection along the lines of his theory of beauty, and thus moves on to the third critique notion of aesthetics (henceforth, in this section, ‘aestheticsc ’). he suggests that we “can think of an aesthetic perfection that contains the ground of a subjectively universal pleasure” where, as he puts it bluntly, “this is beauty.” what kant calls ‘aesthetic perfection of cognition’ is thus concerned not only with the way in which a claim is presented to the senses, i.e. aestheticallyc , but also with whether it is presented in a way that is universally pleasing, i.e. aestheticallyc . more specifically, kant seems to think of the two notions as closely connected and, in particular, of the third critique notion as dependent on the first. strictly speaking, kant claims, judgments of beauty are not about cognition as such but about its sensory expression. as he puts it, “there is really no beautiful cognition…, but only the exhibition [of cognition] can be beautiful.” ‘aesthetic perfection of cognition’ is thus concerned, not with the aestheticc features of abstract propositions that form part of an inferential structure, but with the aestheticsc of their sensory expression. aestheticc reflection can thus be directed at determinate judgments, on kant’s account, if these judgments are given the right sensible representation. and, as we know from the critique of judgment, the right sensible representation is one that leaves room for the free play of the faculties, a representation that suitably expresses the judgment represented, while giving the imagination free reign to run through an indeterminate plethora of associated thoughts. moreover, as we also know from the third critique, aestheticc representations that involve concepts and ideas are the product of the original and exemplary capacity kant calls “genius.” it is this capacity which can produce representations that are suitable for expressing the relevant concepts or ideas, without being wholly determined by those concepts or ideas. it is this capacity, too, which therefore allows us to represent logically distinct cognition in ways that are aestheticallyc pleasing. this is how we can understand kant’s suggestion in the lectures that it is the capacity of genius to bring about the combination of aestheticc with logical perfection: it is in the greatest possible unification of logical with aesthetic perfection in general, in respect to those cognitions that are both to instruct and to entertain, that the character and the art of genius actually shows itself. represented in the right way, a determinate judgment of cognition may thus be appreciated aestheticallyc just as it can be understood conceptually. i argue that there is no reason, on kant’s account, to limit such representations to fine art, or to exclude representations of scientific cognition. goethe’s erlkönig may lead us to understand the conception of vulnerability and violence expressed by the poem, while inspiring us to associations about nature’s power over man, or the weight of parental responsibility. in the same way, i suggest, a representation of the evolutionary lineage of finch species may lead us to grasp darwin’s theory of evolution, while inspiring us to think through implications of the theory we had not previously considered, or draw connections with other natural phenomena we had not previously seen. in both examples, there is room for the free play of the faculties. in both art and science, kant’s theory can thus account for aestheticc pleasure as grounded in the awareness of an indeterminate fit of the object of appreciation with our intellectual capacities. one may object against my proposal that there is an important disanalogy between art and science. one may argue that kant’s transcendental and metaphysical principles, developed in the critique of pure reason and the metaphysical foundations of natural science, ensure that our scientific concepts have determinate application to the phenomena, and hence that any representation of those concepts would leave no room for free play. scientific concepts denote natural kinds or empirical laws that govern natural processes. they can be defined in terms of more familiar concepts, explicated in relation to other theoretical principles, and illustrated by means of examples. art, by contrast, is usually concerned with moral, political or theological ideas, and hence with indeterminate ideas that transcend experience. in order to give sensible expression to these super-sensible concepts, they must be represented indirectly and by means of symbols. it is because of this disanalogy, one might therefore argue, that art requires indirect, symbolic representations, which “occasion… much thinking,” while the concepts and principles of science stand in a determinate relation to natural phenomena and can be illustrated directly and without the use of symbols. newton’s gravitational law, for example, can be illustrated by its application to particular cases. but, according to the present objection, such illustration would leave no room for the free play of the faculties, nor therefore for aestheticc appreciation. in response to this objection it is important to note, however, that on kant’s account expressing the relation between scientific ideas and the objects they represent is more complex than the above contrast between art and science may lead one to assume. according to kant, science is not simply in the business of describing states of affairs but of formulating universal principles and discovering necessary laws whose universal and necessary status is not easily exemplified by individual empirical cases. most importantly, science aims at a unified conception of reality, ordered according to a system of concepts and principles. i argue that it is because the systematic unity of all cognitions is a necessary goal of science, for kant, that scientific representations may demand the imagination to go beyond what is directly expressed by sensory particulars and thus allow for aestheticc reflection. let me spell out this suggestion in some more detail. kant holds that we cannot cognize the world as a determinate and fully unified whole. this cognitive limitation notwithstanding, he also argues that we are necessarily guided by the indeterminate idea of unity in all our scientific investigations. more specifically, in science we must presuppose that all cognition of local phenomena is always part of a larger whole and that it can be systematically related to other parts within that whole. moreover, we have to assume that the objects of those cognitions are such that they can be cognized in this way, and that particular phenomena are systematically related and governed by universal laws. the idea of unity thus guides scientific enquiry and informs scientific cognition. as a concept of reason, however, the idea of unity cannot be represented directly in sensibility. its sensory representation requires the original and exemplary employment of our imaginative and conceptual faculties. in order to sensibly represent the conception of unity that scientific cognition presupposes we therefore need to use indirect, symbolic representations. we have to employ a particular that stands in for the unified whole, and that expresses more than is strictly determined by what we have cognized. i argue that it is representations of this kind that require the original and exemplary activity of genius and can be the object of aestheticc appreciation. scientific representations are thus beautiful, on this conception, when they succeed in expressing a scientific concept or principle while also giving us a glimpse of the unity of nature at which our science aims. kant does not give examples, let alone scientific ones, in his lectures (and one may bemoan that his writing falls foul of his own standards of aestheticc perfection). if my suggestion is right, however, his account allows for such cases of science in the arts as fontenelle’s popular writings. moreover, and more importantly, examples may also include the work of scientists themselves such as geometrical diagrams, physical models, chemical experiments, or biological exemplars that represent in an instance the universal conception implied by the theory. louis pasteur’s separation of mirror-image molecular forms of tartaric acid, for example, is often regarded as one of the most beautiful experiments in the history of chemistry. pasteur’s conceptually simple experiment shows, in a carefully executed way, that chiral molecules— molecules with a right- or left-handed orientation—are optically active. they rotate polarized light, unless there are mirror-image molecular groupings in the mix which cancel the effect. pasteur’s experiment reveals clearly and unambiguously this important truth in chemistry. the beauty of the experiment lies in its capacity to show in one glimpse a universal chemical principle, underlying a whole range of phenomena. at the same time, it leaves indefinite room for the imagination to contemplate the implications of this principle and to run through an inexhaustible string of associated representations. it expresses a universal idea by stimulating thought beyond the particular case represented and by procuring images of the whole of nature for which the principle holds. on the kantian account i suggest, we can appreciate pasteur’s experiment as beautiful because it presents a scientific idea in a way that leaves room for the free play of the faculties. on the kantian conception, i argue, representations of scientific concepts and principles can thus be the object of aestheticc appreciation. as the example of pasteur’s experiment shows, moreover, this account makes good sense of some actual instances of aestheticc judgments in science. to be clear, kant does not spell out this conception of the aestheticsc of scientific representations explicitly. but, as i have argued in this section, his theory provides the necessary resources for it. once we recognize that kant’s express rejection of the beauty of science has limited scope, we can thus see that, on his account, representations of scientific insights can be the object of aestheticc appreciation. . scientific theories and reflective judgment the previous section shows that the kantian conception can account for the aesthetics of sensible representations in science. one may worry, however, that sensible representations are only a marginal part of the enterprise of science. they may be important in formulating, testing, communicating and understanding scientific claims. but they are neither the only nor the central aspect commonly associated with the aesthetic dimension of science. we may, for example, find beauty in einstein’s explanations of the large-scale structure of the universe entirely independently of any particular representation. from the foregoing discussion it is unclear how to account for such a case. does kant’s rejection of the science of beauty commit him, after all, to significantly restricting the scope of the beauty of science, even if he does not rule it out entirely? a positive answer to this question would, i think, be mistaken. for, if we follow the argument of the last section through, we see that the results present a particular instance of a more general kantian insight. this is the recognition that it is not science in the strict sense, but the scientific enterprise broadly construed, that can be the object of aesthetic appreciation. i thus suggest that the insight of the previous section holds not only for sensible representations but also for scientific theories and explanations broadly conceived as the product of spontaneous, creative activity. once again, this suggestion may be received with scepticism. for, once again, science may seem unsuitably determinate to allow for the free reflection that grounds aesthetic appreciation. what, one might ask, is more crucial to kant’s defense of the objectivity of science than his claim that our knowledge of nature is conceptually guided and grounded in the fundamental a priori principles of the understanding? as we know from the first critique and the metaphysical foundations, the transcendental and metaphysical laws of nature govern the formulation of particular scientific concepts and principles. theorizing about the phenomena is essentially structured by a priori rules and importantly different from the free reflection associated with artistic processes. in support of this objection, one might further point to kant’s famous—or, perhaps, infamous—claims about newton. newton may have been a great thinker, kant maintains, but his work lacked the originality of real genius that can only be found in art: everything that newton expounded in his immortal work on the principles of natural philosophy, no matter how great a mind it took to invent it, can still be learned; but one cannot learn to write inspired poetry, however exhaustive all the rules for the art of poetry and however excellent the models for it may be. on kant’s account, the principles of natural philosophy can be taught and learnt. according to the objection, scientific cognition is therefore essentially conceptually determined and, hence, leaves no room for the free reflection required for judgments of beauty. in response to this challenge, however, it is important to read kant’s bold assertions about newton with care. kant contrasts rules for writing inspired poetry with the principles of natural philosophy, and he argues that while the first are unavailable, the second can be taught and learnt. to be precise, kant opposes rules for writing poetry with scientific principles themselves and not with the rules for doing science or formulating theories. as before, kant’s explicit focus is on the fundamental difference between the determinate judgments of science, strictly construed as a system of cognitions, and the indeterminate reflective judgments of aesthetics. but this contrast, by itself, does not rule out the possibility that creative and original reflection plays a role in scientific practice and, hence, that there is beauty in science in the broad sense. the implications of kant’s critical claims about the genius of newton may thus be more limited than is commonly thought. to begin seeing this, it is important to recognize the diversity of scientific practice. much of science follows entirely mechanical procedures. data gathering, hypothesis testing, and the fine-tuning of experiments in response to experimental results are carried out according to more or less standard routines. and yet it is far from obvious that we can spell out determinate rules for all aspects of scientific practice including, in particular, the formulation of new scientific concepts and principles. by contrast, scientific ideas seem often to be discovered in unobvious and roundabout ways. their discovery may involve visual aids, analogical thinking, and more creative sources of inspiration. some original and exemplary thought processes are needed in order to develop ideas that promise new solutions to scientific problems. kant incorporates this thought in his account of reflective judgment. he argues that the a priori determination of cognition by means of the constitutive principles of the understanding is not by itself sufficient for scientific research. the transcendental and metaphysical laws of the first critique and the metaphysical foundations determine the fundamental structure of nature as such, but they leave under-determined the specific character of particular natural phenomena and the specific empirical instantiation of the universal laws that govern those phenomena. as kant puts it in the introduction to the critique of judgment, even according to the a priori “universal laws, without which the form of an experiential cognition in general would not obtain at all,” natural phenomena may still remain incomprehensible to us. they could appear so diverse that it would be impossible for us “to make an interconnected experience out of material that is for us so confused.” scientific understanding of particular natural phenomena is not guaranteed, kant argues, by a simple application of the a priori laws to empirical data. the activities of science thus rely on a further capacity in addition to that of determining judgment. scientific practice requires the work of reflecting judgment, the ability to search for unity among the manifold of particular cognitions. kant recognizes that this capacity consists in comparing and contrasting particular phenomena, following methods of induction and analogy, and that such empirical research is guided by the regulative principle “that what is contingent for human insight in the particular (empirical) laws of nature nevertheless contains a lawful unity.” scientific reflection thus presupposes the idea that the empirical data presented to us can be understood according to unifying concepts and principles whose content is yet to be determined. it relies on the guiding idea that the empirical given is suitable, in an as yet undetermined way, to our unifying ambitions. it follows, on kant’s account, that scientific discoveries are not the result of a completely explicable mechanism, even if the concepts and principles thereby discovered can be fully spelt out. although scientific theorizing aims at concepts and principles that are empirically adequate and, ultimately, provide a true account of the phenomena, it does so by reflecting on how the phenomena form part of a systematic unity of nature as a whole. it requires reflecting on an idea of reason that goes beyond any scientific concepts and principles strictly construed. it thus consists in imaginatively engaging with how this idea may be expressed in, and partially instantiated by, the narrowly scientific concepts and principles that determine the phenomena. i argue, moreover, that this reflective and imaginative capacity is continuous with the original and exemplary ability with which we are familiar from kant’s discussion of art. it consists in searching for conceptual representations that are not fully determined by the principles and ideas already available, and yet nevertheless give adequate expression to these principles and ideas. scientific theories and explanations thus construed result from the attempt of finding instantiations of the universal laws of the understanding that give a partial, and as yet indeterminate, representation of the idea of systematic unity. it is this aspect of scientific reasoning, i suggest, which accounts for its continuity with the reflective activity involved in the creation of art and which may therefore be called an activity of ‘genius’. on the kantian account, the formulation of a particular scientific theory or explanation, just as the sensible representation of scientific ideas considered in the previous section, thus relies on a free and creative intellectual activity. scientific theories and explanations that are the result of this creative activity can, moreover, leave room for the unconstrained reflection that grounds aesthetic pleasure. theories and explanations may prompt us to run through unobserved implication, think about instantiations under novel conditions, and draw out as yet undiscovered connections with other parts of science. they may thereby leave indefinite room to contemplate a wealth of representations, suitably associated with the idea of the unity of nature. i argue that it is this free and imaginative reflection, afforded by theories that are the result of a creative intellectual process, that makes possible the free play of the faculties and thereby grounds aesthetic pleasure. kant does not offer any examples of the aesthetic appreciation of theories and explanations. but we may conceive of it as the pleasure, sometimes described by scientists, of seeing the connection between things, of experiencing the parts fall into place, and of having the whole world in view. we may associate it with the aesthetic experience, in contemplating a theory, of getting a glimpse of that which lies beyond what is strictly determined by the theory, and with the feeling that our minds are in harmony with the world as a whole. it is this experience of being in tune with the world around us, i believe, that is captured by the kantian account. once again, kant does not make this account of the aesthetics of theories and explanations explicit. and, in his statements about newton, he even seems to proclaim views to the contrary when he maintains that “[i]n the scientific sphere… the greatest discoverer differs only in degree from the most hardworking imitator and apprentice.” as i have suggested in this section, however, the denial of scientific genius does not sit well with the implications of kant’s own aesthetic theory. moreover, kant comes close to endorsing these implications when he argues in the critique of judgment that the successful unification of diverse phenomena is recognized with a feeling of pleasure, while disunity is experienced as displeasing. as he puts it, the discovered unifiability of two or more empirically heterogeneous laws of nature under a principle that comprehends them both is the ground of a very noticeable pleasure, often indeed of admiration, even of one which does not cease though one is already sufficiently familiar with its object. on the reading i have suggested, what is considered as pleasing are not any particular properties of the scientific principle. what elicits in us a sense of pleasure, or admiration, is rather the awareness of fit, grounded in the free reflection on the principle that provides us with unified explanations of the phenomena, while leaving room for free reflection on the unity of nature as a whole. one might object, at this point, that my reading confuses the aesthetic appreciation of science with a form of “intellectual” pleasure. in support of this objection, one could point to kant’s further claim that our pleasure in “the comprehensibility of nature and the unity of its division into genera and species” fades over time. one might thus argue that the pleasure associated with unification does not last, because it is connected with the satisfaction of our desire to increase understanding, and therefore subsides once this desire has been met. the pleasure we experience in the unification of scientific principles would thus differ from the “enduring” character of aesthetic pleasure. in response it is fair to acknowledge that kant does not use the term ‘aesthetic’ in this context. nevertheless there is no reason to rule out the possibility of genuine aesthetic pleasure. as kant puts it, we may no longer “notice” the pleasure associated with the unification of empirical laws “only because… it [has] gradually become mixed up with mere cognition.” in other words, in the case of principles or theories that we employ in much of ordinary reasoning, we may no no be longer “attentive” to the kind of free reflection that these principles or theories afford, but only focus on the determinate judgments they strictly entail. we may pay attention only to their content narrowly construed, as we do, for example, in making predictions or testing hypotheses. however, such—admittedly important—focus on the determinate content of scientific claims does not exclude the possibility of also aesthetically appreciating principles and theories broadly construed as the product of a creative intellectual process. considering the empirical adequacy and truth of a theory no more rules out the possibility of also making aesthetic judgments about the theory, than studying a play as an historical source detracts from its aesthetic value. i suggest that we can thus find in kant the resources for a general conception of the aesthetics of science of which the more limited account of the aesthetic perfection of cognition, discussed in the previous section, presents one particular instance. on this account, scientific representations as well as theories—including einstein’s theory of general relativity—are beautiful, if they are the product of a free and creative reflective activity associated with the capacity of genius. just as beautiful representations, scientific theories can be considered as indeterminately expressing an idea that goes beyond the determinate concepts and principles they strictly entail. they leave room for the free play of the faculties, and for a special aesthetic appreciation of beauty in science. kant’s famous claim against the ingenuity of newton should therefore not be read as kant’s only—or even, perhaps, most important—word about the possibility of a beautiful science. it is more plausibly taken as a call for caution against those who mistake determinate cognition with the reflective judgments that ground aesthetic pleasure. kant’s negative claims about newton thus stand alongside the more significant insight that science in the broad sense, as a creative and intellectual endeavor, can be the object of an indeterminate and inexhaustible reflection that grounds aesthetic pleasure. . conclusion on the kantian account i have proposed in this paper, the science of beauty and the beauty of science do not stand or fall together. we can hold on to the latter while letting go of the former. kant’s philosophy thus offers the resources for a positive alternative to the platonic ideal that is expressed and developed by such rationalist philosophers as baumgarten and meier. on the account we can construct from these kantian resources, science can be aesthetically pleasing, not because the claims of science have determinately specifiable aesthetic features, but because the claims and representations of science leave room for the free use of the imagination in reflecting on the inexhaustible richness associated with the systematic unity of nature. on this kantian conception, there are no aesthetic principles to form part of a science of beauty, but there can be genuine aesthetic appreciation of the claims and representations of science. this kantian conception may not account for all aesthetic judgments ever made or ever to be made about science. scientists and science students may use aesthetic statements in a host of different ways. nor does the kantian conception answer all questions about scientific beauty. for example, it remains quiet, so far, about the heuristic role aesthetic judgments may play in science. despite these limitations, however, the account i have proposed captures an important dimension of the aesthetics of science. it thereby shows that kantian aesthetics does not support skepticism about scientific beauty. furthermore, there are even grounds for thinking that the kantian conception may turn out specifically suited to accounting for the role of aesthetics in the search for truth. the conception of scientific beauty i have proposed is directly linked to kant’s theory of cognition. it is tied up with his claim that cognition requires sensibility as much as it requires understanding. and it is intimately connected with his conception of science as essentially incomplete and open-ended. i believe it is an important implication of this close link that, on the kantian account, the aesthetics of science plays a central role in our cognitive endeavors. while i cannot give a definitive defense of this further claim here, i shall end by pointing out a surprising disanalogy between my kantian proposal and the rationalist position that is relevant to such a defense. as we have seen, for baumgarten and meier, aesthetic judgments are a particular species of cognition, offering sensible access to scientific truths. on this conception, aesthetically perfected cognition can provide a first approximation to, and perhaps a way of raising interest in, the more abstract rational insights of science. however, on their account, the aesthetic perfection of cognition pulls in the opposite direction from its logical perfection, since aesthetic judgments do not themselves contribute to the type of clarity demanded of scientific cognition. baumgarten and meier may promise a more intimate relationship between science and beauty. they argue, for example, that the “most perfect” cognition is achieved only by a “beautiful spirit” who, like fontenelle, manages to realize the combined goals of sensible and rational cognition. but this highest perfection can be no more than a compromise. beautiful cognition may satisfy a need of our passions, but this need is 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[cj] kant, immanuel. anthropology, history and education. translated by günter zöller and robert louden. cambridge: cambridge university press, . kivy, peter. “science and aesthetic appreciation.” midwest studies in philosophy ( ): – . kuhn, thomas s. “objectivity, value judgment, and theory choice.” in his essential tension, – . chicago: chicago university press, . kukla, rebecca, ed. aesthetics and cognition in kant’s critical philosophy. cambridge: cambridge university press, . leibniz, gottlieb wilhelm. philosophical papers and letters. edited by leroy e. loemker. dordrecht: reidel, . leibniz, gottlieb wilhelm. philosophical essays. translated by roger ariew and daniel garber. indiana: hackett, . lipton, peter. inference to the best explanation. london: routledge, (second edition). longuenesse, béatrice. “kant’s leading thread in the analytic of the beautiful.” in kukla, aesthetics and cognition in kant’s critical philosophy, – . makkreel, rudolf. “reflection, reflective judgment, and aesthetic exemplarity.” in kukla, aesthetics and cognition in kant’s critical philosophy, – . mcallister, james. beauty and revolution in science. ithaca: cornell university press, . mcallister, james, ed. aesthetics of science, special issue, international studies in the philosophy of science ( ). meier, georg friedrich. auszug aus der vernunftlehre. halle, . (reprinted in: kant, kants werke, vol. xvi). [vern.] meier, georg friedrich. frühe schriften. halle: hallescher verlag, – . vols. i-iii. poincaré, henri. science and method. translated by f. maitland, london: t. nelson and sons, . rueger, alexander. “kant and the aesthetics of nature.” british journal of aesthetics ( ): – . shelley, james. “the problem of non-perceptual art.” british journal of aesthetics ( ): – . sigman, jill and bas van fraassen. “interpretation in science and in the arts.” in realism and representation, edited by george levine, – . madison: university of wisconsin press, . todd, cain. “unmasking the truth beneath the beauty.” international studies in the philosophy of science ( ): – . wenzel, christian. “beauty, genius, and mathematics: why did kant change his mind?” history of philosophy quarterly ( ): – . wolff, christian. vernünftige gedanken von gott, der welt und der seele des menschen, auch allen dingen überhaupt. halle, . [german metaphysics] zammito, john h. the genesis of kant’s critique of judgment. chicago: university of chicago press, . zangwill, nick. the metaphysics of beauty. ithaca: cornell university press, . zangwill, n. “beauty.” in oxford companion to aesthetics, edited by jerrold levinson, - . oxford: oxford university press, . zee, a. fearful symmetry. princeton: princeton university press, . zuckert, rachel. “the purposiveness of form: a reading of kant’s aesthetic formalism.” journal of the history of philosophy ( ): – . zuckert, rachel. “kant’s rationalist aesthetics.” kant-studien ( a): – . zuckert, rachel. kant on beauty and biology: an interpretation of the critique of judgment. cambridge: cambridge university press, b. the literature on this controversy in philosophy of science is vast and diverse. see e.g. duhem, aim and structure of physical theory; kuhn, “objectivity, value judgment, and theory choice”; sigman and van fraassen, “interpretation in science and in the arts”; mcallister, beauty and revolution in science and aesthetics of science; lipton, inference to the best explanation; bangu, “pythagorean heuristic in physics.” the literature in aesthetics is less extensive. see e.g. zangwill, the metaphysics of beauty; todd, “unmasking the truth beneath the beauty”; and the older and less critical discussion in kivy, “science and aesthetic appreciation.” poincaré, science and method, . see also chandrasekhar, truth and beauty: aesthetics and motivations in science and zee, fearful symmetry. see zangwill, the metaphysics of beauty and “beauty”; also rueger, “kant and the aesthetics of nature” and wenzel, “beauty, genius, and mathematics: why did kant change his mind?”. i have developed a first objection to this view in breitenbach, “aesthetics in science: a kantian proposal” and “beauty in proofs: kant on aesthetics in mathematics.” similarly, in her “kant on beauty in science: the aesthetic dimension of cognition”, cohen argues that science can be beautiful on kant’s account. baumgarten first introduced the term “aesthetics” in his meditationes philosophicae de nonnullis ad poema pertinentibus (henceforth med.), translated as reflections on poetry. he developed related reflections on beauty in his metaphysica (henceforth met.) of . baumgarten’s more detailed aesthetica (henceforth aesth.) followed in (vol. i) and (vol. ii) but remained incomplete by the time of his death in . all references are to baumgarten, reflections on poetry: alexander gottlieb baumgarten's meditationes philosophicae de nonnullis ad poema pertinentibus, metaphysics, and aesthetica/Ästhetik. meier’s publications on aesthetics are extensive, including the three-volume anfangsgünde aller schönen wissenschaften ( – ) and many shorter writings from the early ies, collected as frühe schriften zur erziehung der deutschen ( – ). his auszüge aus der vernunftlehre ( , henceforth vern.) set out a summary account of the relation between cognition and aesthetics. for the purposes of this paper, i shall focus only on what baumgarten and meier have in common and set aside their differences. kant relies on met. in his metaphysics lectures and on vern. in his logic lectures throughout his career. see section below. all references to kant are to the volume and page numbers of the akademie edition (kant ff.), except in case of the critique of pure reason (henceforth cpr), which is cited by reference to the a and b pagination of the original and editions. translations are from kant, lectures on logic, practical philosophy, critique of pure reason and critique of the power of judgment, unless indicated otherwise. see met., § and vern., § . on leibniz’ conception of beauty as the feeling of perfection, see his “on wisdom” of c. in his philosophical papers and letters, – . on wolff’s related notion, see his german metaphysics, § ff. met., § . see med., §§ - and vern., § and § . cf. leibniz’s “meditations on knowledge, truth and ideas” from in his philosophical essays, – , and wolff, german metaphysics, § . meier, “gedanken von dem werthe der freyen künste und schönen wissenschaften in absicht auf die obern kräfte der seele,” in his frühe schriften, vol. i, (my translation). see also met., § . baumgarten and meier describe this difference as an increase in “extensive” as opposed to “intensive” clarity. see med., § ; met., § and § ; vern., § . in line with this, baumgarten presents beauty in his later aesthetica as the perfection of sensible cognition itself, and no longer, as he had done in his earlier metaphysica, as the sensible cognition of perfection. see aesth., § . cf. meier, “betrachtungen über den ersten grundsatz aller schönen künste und wissenschaften,” in his frühe schriften, vol. iii, - . one might be tempted to regard this later notion as essentially distinct from baumgarten’s earlier conception of beauty, since, according to the later notion, beauty seems to inhere in the representation and not in the cognition of perfection represented. however, the two notions are not independent. beauty, on the first conception, requires some instantiation of the second. for, whether beauty is primarily grounded in the perfection of the object or in that of its representation, it can only be cognized in the extensively clear but confused manner of the senses. furthermore, the second notion of beauty also requires some instantiation of the first. for even aesthetically perfected representation must constitute a form of the objective cognition of perfection in order to count as the perception of beauty. the perfection of our sensory cognition is possible only if it “complies” with the cognition of the object (baumgarten, “handschrift,” ). on either of the two characterizations of beauty, aesthetic judgments thus consist in the objective cognition of perfection, attained through the senses. what the second notion adds is that the same perfection in the object can be sensibly represented more or less perfectly and hence more or less beautifully. for further discussion, see gregor, “baumgarten’s ‘aesthetica,’” ) who argues that baumgarten’s two definitions result from “a shift in perspective from metaphysician to philosopher of art.” see also beiser, diotima’s children, . guyer, history of modern aesthetics, vol. i, ) furthermore points out that the second definition is no new insight in aesth. but can already be found in med. descartes, the world and other writings and fontenelle, the plurality of worlds. meier, “daß das wesen der dichtkunst in unserer natur gegründet sei,” in his frühe schriften, vol. iii, (my translation). on baumgarten’s reference to fontenelle see his lectures from c. - in his aesth., . in specifying two types of the perfection of cognition, baumgarten’s and meier’s accounts diverge from the traditional rationalist conception of sensory cognition as a merely subordinate insight into what can be cognized more distinctly through reason. as baumgarten puts it, sensible cognition is an “analogon rationis,” an alternative species of cognition that is equally valuable as rational insight (met., § ). for an account of these diverging paths see guyer, history of modern aesthetics, vol. i, – . according to baumgarten and meier, the perfection of sensible cognition can be taught and learnt, and it is the purpose of aesthetics, the “science of sensible cognition,” to spell out the rules and principles (aesth., § , my translation). in met., § , baumgarten also defines aesthetics as the “logic of the inferior cognitive faculties.” meier, “historical and beautiful sciences,” in his frühe schriften, vol. i, (my translation). kant’s aesthetics is often understood as inspired by a rejection of rationalism (e.g. guyer, kant and the claims of taste, ff., and allison, kant’s theory of taste, ff.). other commentators, by contrast, have stressed the continuities between kant and the rationalists (e.g. zuckert, “kant’s rationalist aesthetics”). as i argue in this paper, kant is strongly influenced by, but importantly reinterprets, key rationalist ideas including the distinction between the logical and aesthetic perfection of cognition (see § below). see e.g. cpr, a /b . kant also leaves room for a priori cognition, such as mathematical or transcendental cognition, which has a more complex relation to sensibility than ordinary empirical cognition. for the purpose of this paper, i shall set aside this complication as well as the general question of how kant’s transcendental idealist conception of cognition relates to rationalist metaphysics and epistemology. as will become clear in the following discussion, however, kant’s reinterpretation of the logical and aesthetic perfection of cognition, and his more general account of the beauty of science, are intricately connected with this question. critique of judgment (henceforth cj), : . cj, : . for an outline of kant’s account of cognition see cpr, a /b . on kant’s distinction between determining and reflecting judgments, see cj, : . the arguments i have presented so far may raise the questions of whether or not aesthetic judgment should be regarded as a form of cognition at all, and of whether aesthetic judgment should be classified as (indeterminately) conceptual or, rather, as altogether non-conceptual. see the exchange between ameriks, “kant and the objectivity of taste” and interpreting kant’s critiques, and ginsborg, the role of taste in kant’s theory of cognition and the normativity of nature: essays on kant’s critique of judgment on these questions. for the purpose of my argument, i do not need to settle this debate here. instead, it will be sufficient to show what both parties can agree on, namely, that on kant’s theory the experience of beauty is necessarily linked to our cognitive, albeit purely reflective, engagement with the object, but it is not itself an instance of determinate cognition. as i argue in more detail below, the indeterminate reflection by means of concepts but not the determinate subsumption under concepts leaves room for the experience of beauty. cj, : . cj, : . on the controversial notion of form that kant employs in his aesthetic theory, see the discussion in zuckert, “the purposiveness of form: a reading of kant’s aesthetic formalism.” cj, : . baumgarten’s and meier’s general criteria of aesthetics are in principle unavailable for kant, since judgments of beauty do not stand in any determinate relationship to the character of the object or its representation. kant first makes this point in cpr, a /b , note, before spelling it out in detail in cj, e.g. : . beiser (diotima’s children, ) criticizes kant’s “simple- minded” portrayal of the rationalist conception of a science of beauty, expressed e.g. in kant’s claim that in such a science “it would be determined… scientifically, i.e., by means of proofs, whether something should be held to be beautiful or not” (cj, : ). beiser’s critique is that, pace kant, rationalists such as baumgarten never thought beauty could be inferred a priori from general principles, but rather presented such principles as a means of explaining aesthetic pleasure. even if this is right, however, kant’s critique nevertheless has force. on kant’s account, we must reject even explanatory principles, since objects stand in no determinate relation to aesthetic pleasure. cj, : . cj, : . that aesthetic objects must be sensory is often assumed in contemporary aesthetics. see e.g. binkley, “piece: contra aesthetics,” , and beardsley, aesthetics: problems in the philosophy of criticism, . in “the problem of non-perceptual art,” shelley’s discussion of conceptual art gives a convincing argument against this view and finds historical support in the work of hutcheson. in “kant and the problem of strong non-perceptual art” costello probes shelley’s critique further by drawing on kant. see cj, : . in parallel with the rationalists’ two notions of beauty, kant thus introduces a second conception of aesthetic judgment, specifically concerned with the beautiful representation of art (compare note ). moreover, just as the two rationalist concepts were closely related, in the same way kant’s two types of aesthetic judgment have a common core. both consist in the free play of the faculties and the associated awareness of fit that grounds aesthetic pleasure. kant calls such representations “aesthetic ideas” (cj, : ). for a discussion of this notion, see chignell, “kant on the normativity of taste: the role of aesthetic ideas.” cj, : . cj, : . cj, : . cj, : . cj, : and cpr, a /b . see also cpr, a /b and cj, : . kant only rarely uses the term “science” in a wider sense such as, for example, in the introduction to cpr where he distinguishes the more or less secure paths, and the more or less thorough methods, of science (axii). similarly, kant’s anthropology lectures make use of baumgarten’s met; see the translators introduction in kant, anthropology, history and education, . similar to baumgarten and meier, kant understands perfection as involving “manifoldness and unity” and “the fitness or adequacy of a thing for all sorts of ends” (critique of practical reason, : ). see also his metaphysics of morals, : . jäsche logic (henceforth jl), : . according to kant, sensory representation may come in different forms. in the case of empirical concepts, examples can fulfill this function. in the case of pure a priori concepts, schemata will have to guide their application to sensory material. and, where concepts cannot be applied in sensibility at all, symbolic representation is required. see cj, : ff., and the prize essay “welches sind die wirklichen fortschritte…?,” : – . mrongovius anthropologie nachschriften of - ( : – ), my translation; see also friedländer anthropologie nachschriften of - ( : – ). for a brief discussion of the logical and aesthetic perfection of cognition, see jankowiak and watkins, “meat on the bones: kant’s account of cognition in anthropology lectures,” – . they argue that, “where the critique explains the necessary, a priori structures of cognition, the anthropology transcripts explain the contingent, empirical modes in which the faculties operate in everyday cognition.” jl, : – . kant uses similar formulations throughout the s– s; see blomberg logic, : ff., wiener logic (henceforth wl), : and dohna-wundlacken logic (henceforth dl), : . dl, : . jl, : ; see also jl, : and wl, : . on the relation of aesthetics to the expression of moral ideas, see guyer, kant and the experience of freedom. see e.g. cj, : . cj, : . see cpr, a /b . see e.g. cpr, a /b . kant presents this move from the principle of the unity of cognitions to that of the unity of the object of cognitions as the move from a logical to a transcendental principle. see cpr, a ff./b ff. see kant’s discussion of symbolic representation in cj, : ff. see e.g. ball, elegant solutions: ten beautiful experiments in chemistry. other beautiful examples can be found in förster’s account of hegel’s and goethe’s early biological research, in particular goethe’s experiments with plants in his die jahre der philosophie. cj, : - . see also anthropologie nachschriften, : and – . cj, : . see also kant’s related discussion in the appendix to the transcendental dialectic (cpr, a – /b – ) and at jl, ix – . in cpr, kant conceives of this reflection as the capacity of seeing the universal in the particular, an ability kant famously regards as a talent, or “mother wit,” which cannot be taught by rote but can only be gained through practice (a /b ). cj, : – . kant here refers specifically to the unity of empirical laws. under the heading of judgment as “the capacity to think the particular under the universal” he is equally concerned with the more basic unity of the sensory manifold under concepts (cj, : ). ginsborg ( ) and zuckert ( b) argue, in different ways, for the related claim that there is a common form of judging at the core of kant’s aesthetics and his account of cognition. this claim is a close cousin of my proposal about the continuity between the production of art and science, since the same capacity is involved in producing art and in judging aesthetically. on the question of continuity between aesthetic and determinate conceptual judgments, see also longuenesse, “kant’s leading thread in the analytic of the beautiful,” and makkreel, “reflection, reflective judgment, and aesthetic exemplarity.” for an impressive description of this kind of aesthetic experience in science, see heisenberg, “the meaning of beauty in the exact sciences,” – . cj, : . cj, : . see also cj, : . see cj, : . cj, : . see e.g. cj, : . cj, : . cj, : . this is compatible with zammito’s claim that kant’s views on genius were influenced by his rejection of the german sturm und drang movement, most notably herder, whose anti- rationalism kant famously criticizes (the genesis of kant’s critique of judgment, – ). in his “gerard and kant: influence and opposition”, guyer has furthermore suggested that kant’s views on genius were influenced by, and directed at, alexander gerard’s essay on genius. see also giordanetti’s “das verhältnis von genie, künstler und wissenschaftler in der kantischen philosophie: entwicklungsgeschichtliche betrachtungen” for a discussion of kant’s change of mind about the notion of genius. i’ve said a bit more about this question in breitenbach, “aesthetics in science: a kantian proposal.” a consequence of this is that the ideal (and in principle unattainable) complete science could not be an object of aesthetic appreciation on kant’s account, since it would provide a determinate representation of the unity of nature and, hence, leave no room for indeterminate reflection. baumgarten, “handschrift,” (my translation); see also aesth., § and vern., § . earlier versions of this paper were presented at the university of western ontario, the central european university, the university of essex, the university of bonn, the leuven kant conference and yale university. i am grateful to the audiences at these events for their helpful feedback. special thanks go to john callanan, yoon choi, alix cohen, paul guyer, tiago mata, sasha mudd, clinton tolley, eric watkins, and nick zangwill for stimulating discussions, and to the anonymous referees of this journal for reports that helped me improve the paper. last but not least, i gratefully acknowledge the support of the leverhulme trust and crassh, cambridge for funding my research. -루브릭(미용) ─ ─ 서 론 . 연구의 필요성 선택형 평가 위주이던 중등교육에 학생 스스로 자신의 사 고와 지식, 능력 등을 나타낼 수 있도록 하는 수행평가라는 평가 제도가 도입되어 다양한 교과에서 행해지고 있다. 기존 의 지필고사 위주의 선택형 평가방식의 한계점이 드러나면 서 세계화에 처할 수 있는 인재양성이라는 사회적 요구의 안으로 학생들의 구성적 능력을 평가하는 수행평가 제도 가 강조되기 시작한 것이다. 전통적인 평가 방식인 선택형 검사의 안적 평가 방식으로 등장한 수행평가는 세기 정 한미용학회지 제 권 제 호 journal of investigative cosmetology ( ), ~ ( ) 루브릭(rubric)의 활용이 헤어미용의 학습동기에 미치는 향 권 선 녀 , 유 유 정 , 이 종 숙 ,* 연희미용고등학교, 성결 학교 뷰티디자인학부 effect of rubric application on motivation for learning hair beauty seon-nyeo kwon , yoo-jung yoo and jong-sook lee ,* yunheee beauty high school, kuro, seoul - , korea department of beauty design, sungkyul university, anynang, gyeonggi - , korea (received february , ; revised march , ; accepted march , ) abstract this study developed learner participation rubric for the task of ‘permanent wave’ among beauty and hair beauty units in order to reasonable and objective evaluation in education field. the research was divided into two groups to analyze and compare the learning motivation, an experimental group which is applied rubric and a control group which is not applied rubric. factor analysis was conducted in order to look into interrelation between each question of research tool. as a result, four factors which are relevance, satisfaction, confidence and concentration were extracted based on the questions. in comparison between an experimental group and a control group, the developed rubric affected on the learner’s motivation in all factors such as concentration, relevance, confidence and satisfaction. in the performance evaluation, scores of the experimental group appeared to be higher, and it means that the developed rubric affects the learner’s motivation. also, the correlation analysis showed that there is a correlation between the factors that constitute the learning motivation. thus, if teachers apply a learner-centered rublic for evaluation, learners can make the best use of it for self-directed learning, and it would be able to improve academic achievement. keywords : hair beauty, learning motivation, permanent wave, rubric 본 논문은 석사학위논문을 부분 발췌한 것입니다. *correspondence should be addressed to dr. jong-sook lee, department of beauty design, sungkyul university, anyang, gyeonggi - , korea. ph.: ( ) - , fax: ( ) - , e-mail: sugee @hanmail.net 보화 사회가 요구하는 종합적이고 다양한 고등 정신 능력 을 측정하는 새로운 평가방식으로 인식되면서 학습 환경에 커다란 향을 주었다. 수행평가는 우리나라에 년 국립 교육평가원의 연구 보고서에서 처음 소개되었고, 년 월부터 전국의 초∙중등학교에서 일제히 적용된 이후 여 년이 지나 이제 우리나라에서 수행평가는 학문적 범위를 넘어서 실제 학습 현장에서 실용적으로 이용되는 개념으로 인식되고 있다(김명화 등, ). 수행평가는 학습목표를 어느 정도 달성했는지, 그리고 부 족한 부분이 무엇인지 스스로 평가를 통해 인식하고 교정 할 수 있도록 하는 자기주도 학습이 이루어지도록 하는 것 이다. 학생들은 평가 과제를 수행하면서 절차적 지식 및 응 용력을 향상시킬 수 있는 기회를 갖게 되고, 학습수행 과정 및 결과에 하여 스스로 반성하고 그를 통하여 자신을 이 해하고 자신의 수행을 개선해 보려고 노력할 기회를 부여 받음으로써 수업이나 학습에서 피동적인 존재가 아닌 능동 적인 존재로 느낀다 (한국교육개발원, ). 학생의 능력과 성취를 오직 학생의 선택적 반응 능력인 선택형 지필검사 에 의하여 측정하고, 그러한 측정 결과를 토 로 학생의 진 정한 능력을 간접 평가하는 것이 아니라, 학생들의 구성적 반응 능력으로서의 과제 수행 과정이나 결과로서의 산물을 직접 관찰하고 그 결과를 판단함으로써(허경철, ) 학습 자의 다양한 능력을 신장시키는 것이 평가의 기본 방향이 고 주요 사항(박선희, )이라고 할 수 있다. 이러한 기본 방향과는 달리 수행평가 결과를 처리하는 과정에서 평가의 객관성, 공정성 저하로 교사를 불신하는 경우(김경희, ) 도 나타나며, 손정숙 ( )은 중등학교 실험∙실습 수행평 가에 한 과학교사들의 인식 조사를 위한 심충 면담 결과 에서 명 중 명의 교사들이 객관적이고 명확한 채점 기준 안 없이 태도 정도만 감정하는 형태로 실습 과정을 평가하 고 있기에 객관적이고 명확한 채점 기준안을 개발하려고 노력하거나 다양한 보고서 평가 문항 개발 형태의 평가 도 입의 필요함을 주장하 다. 교과의 특성은 다르지만 수행평 가가 적용되는 방식에 해선 동일하다고 할 수 있으며, 특 성화 고등학교 미용 교과의 수행 평가에서도 명확한 채점 기준이 준비되어 있지 않다면, 이러한 바람직하지 못한 결 과가 초래될 수 있다(김아람, ). 미용과의 교육은 실천적 활동을 강조하는 교과로서 다른 교과와는 달리 지식의 이해뿐만 아니라 창의력, 판단력, 만 들기 능력, 문제 해결 능력 등이 강조되기 때문에 실천적인 태도와 실습 활동이 중요시 (교육과학기술부, )된다. 미 용과 실기수업에서의 평가는 실습에 임하는 자세와 진행 과정은 현장 실무에서 중요한 부분이므로 평가에서도 실습 을 위한 계획, 준비, 과정, 정리∙정돈, 결과 등의 단계별 과 정 평가(교육과학기술부, )가 이루어 져야 한다. 그렇기 때문에 이러한 실험∙실습의 결과를 어떤 기준으로 어떻게 평가할 것인가는 학습자나 교사 모두에게 매우 중요한 부 분이다. 학교 현장의 교육평가 현황을 보면 단순조립이나 기능위 주의 수행평가, 평가를 위한 정교한 체크리스트의 부재 (한 지 , )로 인하여 공정성과 타당성의 문제가 야기되고 평가 결과의 신뢰성에 한 논란도 제기되고 있다 (범선화 와 채정현, ). 평가 결과가 신뢰성을 갖게 하기 위해서 는 평가계획과 방법을 구체적이고 체계적으로 수립할 수 있도록 하는 평가 기준이 있어야 할 것이다. 따라서 교과 특성에 따른 정확한 채점 기준표, 교사의 전문성, 충분한 시 간, 수행 평가와 관련된 자료의 공개, 다양한 평가도구의 개 발 등이 절실히 요구된다. 이에 따라 평가 시 학생의 수행 수준을 기술적으로 진술함으로써 명확한 채점 기준을 제시 해 주는 루브릭(rubrics)이 새로운 안평가 방법의 도구로 써 사용되고 있다(범선화와 채정현, ). 최근 미용 특성화 고등학교의 교육과정이나 방법, 교과내 용 등에 한 다양한 연구가 이루어지고 있지만 루브릭의 장점에도 불구하고 미용교과의 루브릭 개발에 한 연구는 미비한 실정이다. 특히 퍼머넌트 웨이브 단원은 와인딩 시 텐션, 고무밴딩, 로드의 크기와 슬라이스 정도가 주관적으로 평가될 수 있으며, 타 수업에 비해 학생들이 어려워하는 수 업이다. 따라서 퍼머넌트 단원의 수업에 루브릭을 적용할 경우 객관적인 평가가 이루어질 수 있으며, 루브릭 개발 과 정에 학습자들도 직접 참여하여 협상 과정을 통해 교사와 학습자가 함께 평가기준을 토의하고 결과를 도출해낸다면 과제를 수행하는 과정에서의 기 효과는 물론 교수와 학습 자간에도 신뢰관계가 형성되어 학습태도, 학습효과의 향상 에도 좋은 향을 줄 수 있을 것이다. 이에 본 연구에서는 교사와 학습자가 함께 협력하여 헤 어미용 퍼머넌트 웨이브 단원과 관련하여 루브릭을 개발하 고, 개발된 루브릭을 적용했을 때 학습자들의 학습동기에 어떤 향을 미치는지 알아보고자 한다. 이를 통해 교육 현 장에서의 합리적이고 효율적인 교육활동을 위해 타당하고 객관적으로 평가 할 수 있는 평가 자료로 제시하고자 한다. . 루브릭(rubric) ) 루브릭의 개념 루브릭의 어원을 살펴보면, 수도사들이 책을 복사할 때 중요한 부분을 표시하기 위해 붉은 색을 사용했는데, 붉은 색 (red)을 나타내는 라틴어가 ruber로, 루브릭은 책의 주요 경계선에 제목을 표시하는 데서 유래되었다. 이것은 약 년 전부터 교육자들 사이에 새로운 의미로 사용하기 시작 했다. 학생들의 작문을 채점해야 하는 전문가들이 채점을 안내하기 위한 규칙을 설명하는데 “루브릭(rubric)”을 사용 하기 시작했다(popham, ). 루브릭은 전통적인 평가에서 journal of investigative cosmetology vol. , no. , ar x iv :h ep -p h/ v d ec open charm and beauty chiral multiplets in qcd stephan narison laboratoire de physique mathématique et théorique, um , place eugène bataillon, montpellier cedex , france email: narison@lpm.univ-montp .fr we study the dynamics of the the spin zero open charm and beauty mesons using qcd spectral sum rules (qssr), where we observe the important rôle of the chiral condensate 〈ψ̄ψ〉 in the mass-splittings between the scalar-pseudoscalar mesons. fixing the sum rule parameters for reproducing the well-known d( −) and ds( −) masses, we re-obtain the running charm quark mass: m̄c(mc) = . + . − . gev, which confirms our recent estimate from this channel [ ]. therefore, using sum rules with no-free parameters, we deduce mds( +) ≃ ( ± ) mev, which is consistent with the observed ds( ) meson, while a small su( ) breaking of about mev for the ds( +)−d( +) mass-difference has been obtained. we extend our analysis to the b-system and find mb( +) − mb( −) ≃ ( ± ) mev confirming our old result from moment sum rules [ ]. assuming an approximate (heavy and light) flavour and spin symmetries of the mass-splittings as indicated by our results, we also deduce md∗ s ( +) ≃ ( ± ) mev in agreement with the observed dsj ( ). we also get: fd( +) ≃ ( ± ) mev much bigger than fπ= . mev, while the size of the su( ) breaking ratio fds( +)/fd( +) ≃ . ± . is opposite to the one of the − channel of about . . introduction the recent babar, belle and cleo observations of two new states dsj ( ) and dsj ( ) [ ] in the dsπ, dsγ and dsπγ final states have stimulated a renewed interest in the spectroscopy of open charm states which one can notice from different recent theoretical attempts to identify their nature [ ]. in this paper, we will try to provide the answer to this question from qcd spectral sum rules à la shifman-vainshtein- zakharov [ ]. in fact, we have already addressed a similar question in the past [ ], where we have predicted using qssr the mass splitting of the + − − and − − + b̄u mesons using double ratio of moments sum rules based on an expansion in the inverse of the b quark mass. we found that the value of the mass- splittings between the chiral multiplets were about the same and approximately independent of the spin of these mesons signaling an heavy quark-type approximate symmetry: mb( +) − mb( −) ≈ mb∗( +) − mb∗( −) ≈ ( ± ) mev . ( ) the effect and errors on the mass-splittings are mainly due to the chiral condensate 〈ψ̄ψ〉 and to the value of the b quark mass. in this paper, we shall use an analogous approach to the open charm states. however, the same method in terms of the /mc expansion and some other nonrelativistic sum rules will be dangerous here due to the relatively light value of the charm quark mass. instead, we shall work with relativistic exponential sum rules used successfully in the light quark channels for predicting the meson masses and qcd parameters [ ] and in the d and b channels for predicting the (famous) decay constants fd,b [ , , ] and the charm and bottom quark masses [ , , , , ]. the qcd spectral sum rules we shall work here with the (pseudo)scalar two-point correlators: ψp/s (q ) ≡ i ∫ d x eiqx 〈 |t jp/s (x)j†p/s ( )| 〉, ( ) built from the (pseudo)scalar and (axial)-vector heavy-light quark currents: jp/s (x) = (mq ± mq)q̄(iγ )q, jµv /a = q̄γ µ(γ )q . ( ) if we fix q ≡ c and q ≡ s, the corresponding mesons have the quantum numbers of the ds( −), ds( +) mesons. mq and ms are the running quark masses. in the (pseudo)scalar channels, the relevant sum rules for our problem are the laplace transform sum rules: lhp/s (τ) = ∫ ∞ t≤ dt e−tτ π imψhp/s (t), and rhp/s (τ) ≡ − d dτ log lhp/s (τ), ( ) where t≤ is the hadronic threshold, and h denotes the corresponding meson. the latter sum rule, or its slight modification, is useful, as it is equal to the resonance mass squared, in the simple duality ansatz parametrization of the spectral function: π imψhp (t) ≃ f dm dδ(t − m d) + “qcd continuum”Θ(t − tc), ( ) where the “qcd continuum comes from the discontinuity of the qcd diagrams, which is expected to give a good smearing of the different radial excitations . the decay constant fd is analogous to fπ = . mev; tc is the qcd continuum threshold, which is, like the sum rule variable τ, an (a priori) arbitrary parameter. in this paper, we shall impose the τ- and tc-stability criteria for extracting our optimal results. the corresponding tc value also agrees with the fesr duality constraints [ , ] and very roughly indicates the position of the next radial excitations. however, in order to have a conservative result, we take a largest range of tc from the beginning of τ- to the one of tc-stabilities. the qcd expression of the correlator is well-known to two-loop accuracy (see e.g. [ ] and the explicit expressions given in [ , ]), in terms of the perturbative pole mass mq, and including the non-perturbative condensates of dimensions less than or equal to six . for a pedagocial presentation, we write the sum rule in the chiral limit (ms = ), where the expression is more compact. in this way, one can understand qualitatively the source of the mass splittings. the sum rule reads to order αs: lhp/s (τ) = m q { ∫ ∞ m q dt e−tτ π [ t( − x) [ + (ᾱs π ) f(x) ] + o(α s) ] + c 〈o 〉p/s + τc 〈o 〉p/s e−m qτ } , ( ) the different terms are : x ≡ m q/t, f(x) = + li (x) + log x log( − x) − log( /x − ) − log( − x) + x log( /x − ) − (x/( − x)) log x, c 〈o 〉p/s = ∓mq〈d̄d〉 e−m qτ + 〈αsg 〉 ( − m qτ ) / π c 〈o 〉p/s = ∓ mq ( − m qτ ) g〈d̄σµν λa gµνa d〉 ( ) − ( π ) ( − m qτ − m qτ ) ραs〈ψ̄ψ〉 , ( ) where we have used the contribution of the gluon condensate given in [ ], which is ir finite when letting mq → . the previous sum rules can be expressed in terms of the running mass m̄q(ν) through the perturbative two-loop relation [ ]: mq = m̄q(p ) [ + ( + ln p m q ) (ᾱs π ) + o(α s) ] , ( ) where mq is the pole mass. throughout this paper we shall use the values of the qcd parameters given in table . at the optimization scale, its effect is negligible, such that a more involved parametrization is not necessary. we shall include the negligible contribution from the dimension six four-quark condensates, while we shall neglect an eventual tachyonic gluon mass correction term found to be negligible in some other channels [ ]. notice a missprint in the expression given in [ , ] which does not affect the result obtained there. the numerical change is negligible compared with the original expression obtained in [ ]. table : qcd input parameters used in the analysis. parameters references Λ = ( ± ) mev [ ] Λ = ( ± ) mev [ ] m̄b(mb) = ( . ± . ) gev [ , , , ] m̄s( gev) = ( ± ) mev [ , , , ] 〈d̄d〉 / ( gev)=−( ± ) mev [ , , ] 〈s̄s〉/〈d̄d〉 = . ± . [ , ] 〈αsg 〉 = ( . ± . ) gev [ , ] m = ( . ± . ) gev [ , ] αs〈ψ̄ψ〉 = ( . ± . ) × − gev [ , , ] we have used for the mixed condensate the parametrization: g〈d̄σµν λa gµνa d〉 = m 〈d̄d〉, ( ) and deduced the value of the qcd scale Λ from the value of αs(mz ) = ( . ± . ) [ , ]. we have taken the mean value of ms from recent reviews [ , , ]. calibration of the sum rule from the d( −) and ds( −) masses and re-estimate of m̄c(mc) figure : τ in gev− -dependence of the a) md( −) in gev for m̄c(mc) = . gev and b) mds( −) in gev for m̄c(mc) = . gev at a given value of tc = . gev . the dashed line is the result including the leading 〈ψ̄ψ〉 contribution. the full line is the one including non-perturbative effects up to dimension-six. this analysis has been already done in previous papers to order αs and α s and has served to fix the running charm quark mass. we repeat this analysis here to order αs for a pedagogical purpose. we show in fig. a), the τ-dependence of the d( −) and in fig b) the one of the ds( −) masses for a given value of tc, which is the central value of the range: tc = ( . ± . ) gev , ( ) where the lowest value corresponds to the beginning of τ-stablity and the highest one to the beginning of tc stability obtained by [ , , ] in the analysis of fd and fds . this range of tc-values covers the different choices of tc used in the sum rule literature. as mentioned previously, the one of the beginning of tc-stability cöıncides, in general, with the value obtained from fesr local duality constraints [ , ]. using the input values of qcd parameters in table , the best fits of d( −) (resp. ds( −)) masses for a given value of tc = . gev correspond to a value of m̄c(mc) of . (resp. . ) gev. taking the mean value as an estimate, one can deduce: m̄c(m c ) = ( . + . − . ± . ± . ± . ) gev , ( ) where the errors come respectively from tc, 〈ψ̄ψ〉, Λ and the mean value of mc required from fitting the d( −) and ds( −) masses. this value is perfectly consistent with the one obtained in [ , ] obtained to the same order and to order α s, indicating that, though the α s corrections are both large in the two-point function and mc [ ], it does not affect much the final result from the sum rule analysis. in fact, higher corrections tend mainly to shift the position of the stability regions but affect slightly the output value of mc. this value of mc is in the range of the current average value ( . ± . ) gev reviewed in [ , , ]. however, it does not favour higher values of mc allowed in some other channels and by some non relativistic sum rules and approaches. however, these non relativistic approaches might be quite inaccurate due to the relative smallness of the charm quark mass. higher values of mc would lead to an overestimate of the d( −) and ds( −) masses. in the following analysis, we shall use the central value m̄c(mc) = . (resp. . ) gev for the non-strange (resp. strange) meson channels. the + − − meson mass-splittings figure : similar to fig. but τ-behaviour of mds( +) for given values of tc = . gev and mc(mc) = . gev. • we study in fig. ), the τ-dependence of the ds( +) mass at the values of tc and mc obtained previously. in this way, we obtain: mds( +) ≃ ( + + − − ± ± ± ) mev =⇒ mds( +) −mds( −) = ( ± ) mev , ( ) where the errors come respectively from tc, mc, 〈ψ̄ψ〉, ms, and Λ. we have used the experimental value of mds( −). the reduction of the theoretical error needs precise values of the continuum threshold and of the charm quark mass which are not within the present reach of the estimate of these quantities. further discoveries of the continuum states will reduce the present error in the splitting. one should also notice that in the ratio of sum rules with which we are working, we expect that perturbative radiative corrections are minimized though individually large in the expression of the correlator and of the quark mass. • the value of the mass-splittings obtained previously is comparable with the one of the b( +)-b( −) given in eq. ( ), and suggests an approximate heavy-flavour symmetry of this observable. • we also derive the result in the limit of su( )f symmetry where the strange quark mass is put to zero, and where the 〈ψ̄ψ〉 condensate is chirally symmetric (〈s̄s〉 = 〈d̄d〉). in this case, one can predict an approximate degenerate mass within the errors: mds( +) − md( +) ≃ mev , ( ) the range of tc values - gev obtained previously for the d( −) mesons cöıncides a posteriori with the corresponding range for the d( +) meson if one assumes that the splitting between the radial excitations is the same as the one between the ground states, i.e about mev. we have cheked during the analysis that this effect is unimportant and is inside the large error induced by the range of tc used. which indicates that the mass-splitting between the strange and non-strange + open charm mesons is almost not affected by su( ) breakings, contrary to the case of the − mesons with a splitting of about mev. • we extend the analysis to the case of the b( +) meson. here, it is more informative to predict the ratio of the + over the − masses as the prediction on the absolute values though presenting stability in τ tend to overestimate the value of mb. we obtain: mb( +) mb( −) ≃ ( . ± . ± . ± . ± . ) =⇒ mb( +) −mb( −) ≃ ( ± ) mev , ( ) where the errors come respectively from tc taken in the range − gev , mb, 〈ψ̄ψ〉, and τ. it agrees with the result in eq. ( ) obtained from moment sum rules [ ]. we have used the value of m̄b(mb) given in table . the + − − meson mass-splitting our previous results in eqs. ( ), ( ) to ( ) suggest that the mass-splittings are approximately (heavy and light) flavour and spin independent. therefore, one can write to a good approximation the empirical relation: mds( +)−mds( −) ≈ md( +)−md( −) ≈ mb( +)−mb( −) ≈ mb( +)−mb( −) ≈ md∗s ( +)−md∗s ( −) . ( ) using the most precise number given in eq. ( ), one can deduce: md∗s ( +) − md∗s ( −) ≃ ( ± ) mev =⇒ md∗s ( +) ≃ ( ± ) mev . ( ) this result is consistent with the + assignement of the c̄s meson dsj ( ) discovered recently [ ]. in a future work, we plan to study in details this spin one channel using qssr. the d( +) and ds( +) decay constants figure : similar to fig. but τ-behaviour of fd( +) for given values of tc = . gev and m̄c(mc) = . gev. for completing our analysis, we estimate the decay constant fd( +) analogue to fπ = . mev. we show the behaviour of fd( +) versus τ, where a goood stablity is obtained. adopting the range of tc-values obtained previously and using m̄c(mc) = . + . − . gev required for a best fit of the non strange d( +) meson mass, we deduce to two-loop accuracy: fd( +) = ( + + − − ± ± ) mev , ( ) where the errors come respectively from the values of tc, mc, 〈ψ̄ψ〉 and Λ. we have fixed md( +) to be about mev from our previous fit. it is informative to compare this result with the one of fd = ( ± ) mev, where the main difference can be attributed by the sign flip of the quark condensate contribution in the qcd expression of the corresponding correlators. a numerical study of the su( ) breaking effect leads to: rs ≡ fds( +) fd( +) ≃ . ± . , ( ) which is reverse to the analogous ratio in the pseudoscalar channel fds/fd ≃ . ± . given semi- analytically in [ ]. in order to understand this result, we give a semi-analytic parametrization of this su( ) breaking ratio. keeping the leading term in ms and 〈ψ̄ψ〉, one obtains: rs ≃ ( − ms mc ) [ − . 〈s̄s − d̄d〉 ] / ( mds( +) md( +) ) ≃ . , ( ) where the main effect comes from the negative sign of the ms contribution in the overall normalization of the scalar current, while the meson mass ratio does not compensate this effect because of the almost equal mass of ds( +) and d( +) obtained in previous analysis. this feature is opposite to the case of fd( −). summary and conclusions due to the experimental recent discovery of the dsj ( ) and d ∗ sj ( ), we have analyzed using qssr the dynamics of the ± and ± open charm and beauty meson channels: • we have re-estimated the running charm quark mass from the d and ds mesons. the result in eq. ( ) confirms earlier results obtained to two- and three-loop accuracies [ , ]. • we have studied the mass-splittings of the +- − in the d systems using qssr. our result in the ( +) channel given in eq. ( ) agrees with the recent experimental findings of the dsj ( ) suggesting that this state is a good candidate for being a c̄s + meson. • we also found, in eq. ( ), that the su( ) breaking responsible of the mass-splitting between the ds( +) and d( −) is small of about mev contrary to the case of the pseudoscalar ds-d mesons of about mev. • we have extended our analysis to the b-system. our results in eqs. ( ), ( ) and ( ) suggest an approximate (light and heavy) flavour and spin symmetries of the meson mass-splittings. we use this result to get the mass of the c̄s d∗s ( +) meson in eq. ( ), which is in (surprising) good agreement with the observed d∗sj ( ). • using qssr, we have also determined the decay constants of the + mesons and compare them with the ones of the − states. the result in eq. ( ), which is similar to the pseudoscalar decay constant fd ≃ mev, suggests a huge violation of the heavy quark symmetry / √ md scaling law. finally, our results in eqs. ( ) and ( ) indicate that the su( ) breaking act in an opposite way compared to the case of the − channels. experimental or/and lattice measurements of the previous predictions are useful for testing the validity of the results obtained to two-loop accuracy in this paper from qcd spectral sum rules. however, a complete confirmation of the nature of these new states needs a detail study of their production and decays. we plan to come back to these points in a future work. during the editorial preparation of this paper, there appears in the literature a paper using sum rules method to the same channel [ ]. instead of our result in eq. ( ): mds( +) = ( ± ) mev, the authors obtain mds( +) = ( ± ) mev which is higher than the babar result ds( ) by about mev. considering this deviation as significant, the authors conclude that the experimental candidate cannot be a c̄s state contrary to the conclusion reached in the present paper. however, by scrutinizing the analysis of ref. [ ], we find that the true errors of the analysis have been underestimated: • as one can see from their figures, the quoted error of mev only takes into account the one due to the choice of the qcd contiuum threshold taken in a smaller range . - . gev , than the more conservative value - gev used in the present paper, which induces a larger error of - mev. • the high central value obtained in [ ] is related to a higher choice of the (ill-defined) charm quark pole mass of . gev compared to the value . gev which would have been deduced from its relation with the running charm quark mass . gev in eq. ( ) used in this paper to reproduce the ds( −) mass. as the analysis is very sensitive to mc, its induced error should be included in the final number. with mc in eq. ( ), this uncertainty is about mev, and might be bigger if one considers all range of mc given in the literature. in this paper, we have used md andmds as alternative channels for extracting mc. • taking properly the different sources of errors including the running of condensate and the effects of some other anomalous dimensions, one then leads to a consistency within the errors of both theoretical estimates with the present data. references [ ] s. narison, phys. lett. b ( ) . [ ] s. narison, phys. lett. b ( ) . [ ] for a review see e.g., m. bondioli, for the babar collaboration, nucl. phys. (proc. suppl.) b ( ) and references therein. [ ] m.a. shifman, a.i. vainshtein and v.i. zakharov, nucl. phys. b ( ) , . [ ] for a review and references to original works, see e.g., s. narison, qcd as a theory of hadrons, cambridge monogr. part. phys. nucl. phys. cosmol. ( ) - [hep-ph ]; qcd spectral sum rules , world sci. lect. notes phys. ( ) - ; acta phys. pol. ( ) ; riv. nuov. cim. n ( ) ; phys. rep. ( ). [ ] see e.g.: s. narison, phys. lett. b ( ) ; phys. lett. b ( ) ; nucl. phys. (proc. suppl.) b ( ) . [ ] see e.g.: s. narison, phys. lett. b ( ) ; b ( ) . [ ] see e.g., s. narison, [hep-ph ]; nucl. phys. (proc. suppl.) b ( ) . [ ] r.a. bertlmann, g. launer and e. de rafael, nucl. phys. b ( ) . [ ] f.v. gubarev, m.i. polikarpov and v.i. zakharov, nucl. phys. (proc. suppl.) b ( ) ; v.i. zakharov, nucl. phys. (proc. suppl.) b ( ) ; k. chetyrkin, s. narison and v.i. zakharov, nucl. phys. b ( ) . [ ] s. generalis, j. phys. g ( ) ; m. jamin and m. münz, z. phys. c ( ) . [ ] v.a. novikov et al, neutrino conference, purdue univ. . [ ] r. tarrach, nucl. phys. b ( ) ; [ ] s. narison, phys. lett. b ( ) ; b ( ) . [ ] s. narison, phys. lett. b ( ) ; b ( ) . [ ] see e.g. m. jamin, talk given at qcd , - th july , montpellier-fr. [ ] h.g. dosch and s. narison, phys. lett. b ( ) . [ ] s. narison, phys. lett. b ( ) ; s. narison et al., nuovo. cim a ( ) . [ ] s. narison, phys. lett. b ( ) ; b ( ) . [ ] g. launer et al., z. phys. c ( ) . [ ] pdg , k. hagiwara et al., phys. rev. d ( ) . [ ] s. bethke, nucl. phys. (proc. suppl.) b, a ( ); hep-ex/ . [ ] k.g. chetyrkin and m. steinhauser, eur. phys. j. c ( ) and references therein; k. melnikov and t. van ritbergen, phys. lett. b ( ) . [ ] s. narison, phys. lett. b ( ) . [ ] a. hayashigaki and k. terasaki, hep-ph/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ex/ http://arxiv.org/abs/hep-ph/ introduction the qcd spectral sum rules calibration of the sum rule from the d( -) and ds( -) masses and re-estimate of " mc(mc) the +- - meson mass-splittings the +- - meson mass-splitting the d( +) and ds( +) decay constants summary and conclusions wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ t e c h n o l o g y inventing beauty robert p. crease revels in the life of a hollywood goddess who pioneered wireless technology. hedy lamarr was no mere hollywood starlet. the twentieth-century aus-trian–american actress was also a tech-head, taking inspiration from the self- playing ‘player piano’ to create technology of a type now used in mobile phones. richard rhodes’s biography, hedy’s folly, gives this side of her story its due. for some, her intelligence sits uneasily with her exquisite looks, and her invention looks like an eccentric sideline. another biography — hedy lamarr by cinematic scholar ruth barton, published last year — was a solid portrait but devoted just ten pages to lamarr’s undercover life as an inventor. however, her engineering work, conducted largely in collaboration with avant-garde us composer and pianist george antheil, was genuine. the duo patented a wire- less technology to prevent jamming of remote-controlled torpedoes. this was the first use of a system that, thanks to the particular way in which it allowed multiple users to share a common band, would later be incorporated into wi-fi, bluetooth and most cordless phones. an award-winning author on the history of the us atomic-weapons programme, rhodes puts lamarr’s inventive spirit into coherent context. despite its title, the book is nearly as much about antheil: he spent the s in europe writing controversial composi- tions for player pianos — an early form of entertainment centre involving a primitive version of digital control. antheil’s ‘orchestras’ incorporated other far- out instruments: saws, hammers, electric bells, sirens and even a pair of aeroplane propellers. rhodes is not as good at conjuring the cultural climate as he is at describing technolo- gies, so the book only really takes off when lamarr meets antheil in hollywood in . but t he c el ebr it y - riddled parties, open- ings and european premieres of lamarr’s day job were hardly a drab background to her hidden hobby, and her progression to stardom makes for fascinating reading. b orn in to a jewish family in vienna as hedwig kiesler, she grew into a beautiful teenager and was soon appearing in german films. the erotically charged czech film ecstasy made her a sensation: in it, she swims backstroke nude in a shimmering lake, and appears, famously, with bare breasts. that summer, kiesler married the first of her six husbands, a wealthy arms merchant who entertained german and austrian weapons developers. neither he nor his guests seemed to appreciate that their gor- geous hostess could follow conversations about submarine torpedoes and remote- control devices. when her husband tried to make her give up acting, she divorced him. kiesler moved to hollywood, became hedy lamarr, and was soon a ravishing starlet in films such as algiers ( ), the trailer for which contained the line (uttered by french actor charles boyer): “come with me to zee casbah!” but she was proud of her mental acuity. “any girl can be glamorous,” she said. “all you have to do is stand still and look stupid.” during the second world war, lamarr played glamour roles in films such as ziegfeld girl ( ), in which she wore a jewelled peacock-feather headdress. meanwhile, she and antheil had been hard at work applying for patents on weapons-related devices. their meeting and collaboration came at a fortuitous time for antheil. he had been down on his luck, reduced to writing popu- lar articles for esquire magazine advising readers to evaluate women based on their glands. lamarr hoped to tap into his exper- tise to find a way to augment her breasts. antheil couldn’t help her, but the two dis- covered a shared passion for pianos and for inventing. (rhodes finds it “highly unlikely” that they were lovers.) lamarr happened to mention an idea she’d had about how to prevent jamming of remote-controlled torpedoes. rhodes puts this simply: “if a radio transmitter and receiver are synchronized to change their hedy lamarr co-invented a technology to prevent remote-controlled torpedoes from being jammed. hedy’s folly: the life and breakthrough inventions of hedy lamarr, the most beautiful woman in the world richard rhodes doubleday: . pp. $ . e . c a r p e n t e r /m g m /t h e k o b a l c o l l e c t io n nature.com for more on women and patents: go.nature.com/t u kp | n a t u r e | v o l | n o v e m b e r books & artscomment © macmillan publishers limited. all rights reserved and so it goes: kurt vonnegut, a life charles j. shields henry holt pp. £ ( ) the late kurt vonnegut carved out his own literary landscape — blending dystopian tendencies, pitch-dark humour, autobiography and elements of his grounding in chemistry. authorized biographer charles j. shields’s exhaustive research does justice to him. whether it is the dimension-hopping trafalmadorians, ice-nine (a solid water) or the shenanigans of fictional sci-fi writer kilgore trout, vonnegut used the fantastical to comment astutely on the human condition. his honesty, shields reminds us, is still needed. small, gritty, and green: the promise of america’s smaller industrial cities in a low-carbon world catherine tumber mit press pp. $ . ( ) detroit in michigan may be motown — an intrepid city founded on car manufacture — but depopulation, ill-conceived infrastructure and the flight of industry have left it devastated. yet historian and journalist catherine tumber sees such urban wastelands as tomorrow’s sustainability hubs. low population density, proximity to farmland, and a skilled workforce could aid the advent of renewable-energy technology. plucking ideas from small cities in the us rust belt, tumber outlines a plausible route to a ‘repurposed’ future. memory: fragments of a modern history alison winter university of chicago press pp. £ . ( ) notions of how memory works have shifted wildly over time. historian alison winter traces the evolution of memory sciences through ‘fragments’, or flashbulb moments. drawing on sources from neurological research to diaries, she shows how the understanding of memory has deepened, ramified and sometimes taken wrong turns. case studies include the extreme brain surgery performed by canadian neurosurgeon wilder penfield; forensic hypnosis (as used in the book the manchurian candidate); psychologist frederic bartlett’s studies of remembering; and false-memory syndrome. science on ice: four polar expeditions chris linder university of chicago press pp. £ ( ) a century of polar science has seen vast change, not least in the researchers still braving the blizzards and gelid waters. to give an idea of their daily realities, oceanographer and photographer chris linder and several embedded journalists followed four arctic and antarctic expeditions studying, variously, an adelie penguin colony, the bering sea in spring, the greenland ice sheet and ocean pack ice in the eastern arctic. the vivid images — of fishing for zooplankton at dawn, intent ice-breaking crews, ernest shackleton’s hut at cape royds, for instance — enliven a detailed yet accessible chronicle. mushroom nicholas p. money oxford university press pp. $ . ( ) botanist nicholas money is unashamedly in thrall to the ‘fungal sex organ’. in this brilliant scientific and cultural exploration, these organisms of rot and soil positively sparkle. from biology to medicine, cuisine and recreation, this is a history as convoluted as the systems of fungal filaments that enrich woodlands. a human and mycological cast of thousands throngs the pages — from a -kilometre-square colony of honey fungus in oregon’s malheur national forest, to charles mcilvaine, author of one thousand american fungi, who fearlessly chomped his way through many of them. tuning simultaneously, hopping together randomly from frequency to frequency, then the radio signal passing between them can- not be jammed.” this process is now referred to as ‘frequency hopping’ or ‘spread spec- trum’. experience with player pianos had made antheil proficient at getting machines to communicate in synchrony, so lamarr recruited him to provide a proof of principle. using available documents and inter- views, rhodes retraces the steps that guided lamarr in her thinking, and the genesis and development of the pair’s other inven- tions. he explains why the us navy had no immediate use for the patent: its existing tor- pedoes were so problematic that it had no interest in developing another system, and navy technicians misunderstood aspects of the lamarr–antheil design. so it was filed away. rhodes charts the later, independ- ent developments of the technology and its subsequent uses, notably in the sonobuoy (a sonar system in a buoy) developed by the us navy. the patent expired the year antheil died, in , when it was still classified. the technology the two invented emerged from secrecy in and found wide appli- cation in commercial communications. in , the inventors were given (antheil post- humously) a pioneer award by the electronic frontier foundation, a non-profit com- munications industry group based in san francisco, california. but from the end of the s, lamarr’s hollywood career had begun to drift down an all-too-familiar path. her film performances had grown hammier, as in the overwrought and pretentious samson and delilah ( ). she gradually acquired a reputation reminiscent of sunset boule- vard’s norma desmond, was arrested twice for shoplifting and died in . although the book is mainly about her collaboration with antheil, its cover sports a collage of lamarr the starlet sitting on a long golden torpedo. yet again we are asked to marvel at the spectacle of actress–inventor as oddity. does this reflect sexism, the disbelief that beauty is compatible with intelligence? would we be less surprised if her on-screen persona had been less erotic and more like katharine hepburn’s? or perhaps there is a deeper cultural prejudice at work — the platonic notion that the skill involved in imitating the world is incompat- ible with that of understanding it. inside its cover, rhodes’s book gives us the whole hedy — a closet geek in peacock feathers — and makes that mix believable. now it is up to us to figure out why we find that hard to digest. ■ robert p. crease is a philosopher at stony brook university, new york, usa. he is a columnist for physics world, and his latest book is world in the balance. e-mail: rcrease@notes.cc.sunysb.edu n o v e m b e r | v o l | n a t u r e | books & arts comment books in brief © macmillan publishers limited. all rights reserved technology: inventing beauty the beauty in facial esthetics: gummy smile and options of treatment the saudi journal for dental research ( ) , – king saud university the saudi journal for dental research www.ksu.edu.sa www.sciencedirect.com the beauty in facial esthetics: gummy smile and options of treatment peer review under responsibility of king saud university. production and hosting by elsevier - � production and hosting by elsevier b.v. on behalf of king saud university. http://dx.doi.org/ . /j.sjdr. . . gummy smile is defined as exposure of a large amount of gin- gival tissues it is also known as a high lip-line. numerous fac- tors attribute to the gummy smile condition, such as; hyperactivity of the orbicularis oris muscle, altered passive eruption and reason connected to the dentogingival com- plex. – additional factors determine the smile-line like the form and volume of the lips, the facial muscles, the teeth, and the gingival tissue. the ideal situation for an esthetic smile is the exposure of minimal gingival tissues with normal teeth height and a good balance with the upper lip. as the facial esthetics can be severely affected by the gummy smile, consideration of the available options of treat- ment is a must to adjust the condition but only upon the patient request. one of the earliest ways to correct this prob- lem was to undergo orthognathic surgery to reposition the front segment of the upper jaw when the patient has a basal bone deformity. however, because of the surgical difficulty, the pain, the hospitalization, and the intrinsic complications, patients are not enthusiastic to go through this treatment. , accordingly other treatment alternatives were established, which are less painful and less expensive. lip repositioning procedure is one of these procedures ; it is a possible and inex- pensive option of treatment. it is a relatively simple approach where by repositioning of the upper lip to a lower position with some minor periodontal cosmetic surgery minimizes the appearance of a high lip line. , the procedure is performed under local anesthetic and involves the surgical re-attachment of the gingival tissue under the lip to restrict the extent that the lip can go excessively upward when smiling. the result of this procedure is very satisfying to the patient. – gingivectomy is another approach of treatment. however, gingivectomies can only be performed when reduction of gin- gival tissues is minimal. the tissue is removed with gingivec- tomy knives, # blades, dental laser or by radiosurgery. the advantages of this technique include; reduced pain, no sutures, and fast healing. – however, when extensive reduction of the tissue is required then crown lengthening procedures are the treatment of choice. , in this technique, contouring of the gingival tissues around each individual tooth with the accompanying bone is done followed by repositioning of the gingival tissues to the new position using sutures. the sutures are then removed after – days. – although gingivectomy and crown lengthening procedures are not as invasive as the other surgical procedures, however, the move to a less invasive treatment options in esthetic den- tistry was required. this led to the use of botox in dental esthetics. botox was used primarily for smoothing wrinkles of the forehead, the glabellar region and around the corners of the eyes. seven to eight percent of north american dentists provide botox treatment to their patients as a part of cosmetic treat- ment. the significant adjunctive therapy that botox adds to the esthetics dental treatment is a fact lacked by many den- tists. botox is a muscle relaxer and when used in the upper lip it can significantly decrease the strength of the muscle contrac- tions that cause the high lip line. the non-surgical approach of using botox to treat gummy smile is one of the advantages of this approach. botox weakens the orbicularis oris muscle so they cannot raise the lip as high as before. this procedure is technique sensitive, as the patients should maintain full lip competency allowing them to speak, smile, and eat normaly. , as dentists, it is very important to present all options of treatments for gummy smile to the patient. advantages and disadvantages of all options should be explained carefully to the patients as well. the advantages of the surgical treatment options of orthognathic surgery, such as lip repositioning and crown lengthening, are permanent esthetic results. the dis- advantages are the frequency of the appointments, the high cost, possible complications of treatment including sensitivity, recession and possibility of endodontic therapy later on. – the advantages of treatment with botox and dermal fillers are immediate results with no removal of tooth structure. the disadvantages include; re-treatment – times a year and the cost associated with that treatment. in conclusion; patients with gummy smile can be safely, simply, and successfully trea- ted (when indicated) in the dental office. although, different http://crossmark.crossref.org/dialog/?doi= . /j.sjdr. . . &domain=pdf http://dx.doi.org/ . /j.sjdr. . . http://dx.doi.org/ . /j.sjdr. . . http://www.sciencedirect.com/science/journal/ http://dx.doi.org/ . /j.sjdr. . . editorial options of treatments are available and it makes no difference what type of treatment the patient chooses, however, the den- tist exposure to the different available treatment approaches significantly expands the treatment choices we provide to the patients. references . robbins jw. 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combined approach for the correction of gummy smile. plast reconstr surg ; : – . . kao rds, frangadakis k, salehieh j. esthetic crown lengthening: appropriate diagnosis for achieving gingival balance. j calif dent assoc ; : – . . chu sks, mistry s. short tooth syndrome: diagnosis, etiology, and treatment management. j calif dent assoc ; : – . . lee ea. crown lengthening: classification, biologic rationale and treatment planning considerations. pract proced aesthetic dent ; : – . . khanna b. facial aesthetics-starting out. aesthet dent today ; ( ): – . . khanna b. lip stabilisation with botulinum toxin. aesthet dent today ; ( ): – . . polo m. botulinum toxin type a (botox) for the neuromuscular correction of excessive gingival display on smiling (gummy smile). am j orthod dentofacial orthop ; : – . editor in chief nahid y. ashri http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h 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http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h http://refhub.elsevier.com/s - ( ) - /h the beauty in facial esthetics: gummy smile and options of treatment references lbs research online c cryder, s botti and y simonyan the charity beauty premium: satisfying donors’ “want” versus “should” desires article this version is available in the lbs research online repository: http://lbsresearch.london.edu/ id/eprint/ / cryder, c, botti, s and simonyan, y ( ) the charity beauty premium: satisfying donors’ “want” versus “should” desires. journal of marketing research, ( ). pp. - . issn - doi: https://doi.org/ . /jmr. . american marketing association https://journals.sagepub.com/doi/ . /jmr. . ... users may download and/or print one copy of any article(s) in lbs research online for purposes of research and/or private study. further distribution of the material, or use for any commercial gain, is not permitted. https://lbsresearch.london.edu/view/lbs_authors/ .html http://lbsresearch.london.edu/id/eprint/ / http://lbsresearch.london.edu/id/eprint/ / https://lbsresearch.london.edu/view/lbs_authors/ .html https://doi.org/ . /jmr. . https://journals.sagepub.com/doi/ . /jmr. . the charity beauty premium: satisfying donors' want versus should desires cynthia cryder simona botti yvetta simonyan* * cynthia cryder (cryder@wustl.edu) is an associate professor of marketing at olin business school, washington university in st. louis, campus box , one brookings dr. st. louis, mo , - - . simona botti (sbotti@london.edu) is an associate professor of marketing, london business school, regent’s park, london nw sa, united kingdom, + ( ) . yvetta simonyan (i.simonyan@bham.ac.uk) is a lecturer at birmingham business school, university of birmingham, edgbaston park road, birmingham, b ty, united kingdom, + ( ) . we thank charles dorison, rachel gershon, katherine jaruzelski, michael lory, the consumer behavior lab at washington university in st. louis and the behavioral research lab at london business school for research assistance. we also thank hengchen dai and theresa kelly for useful insights and stefano puntoni and claudia townsend for providing valuable feedback on an earlier draft. correspondence: cynthia cryder. tel:% b % % % % % tel:% b % % % % % tel:+ % % % % the charity beauty premium: satisfying donors’ want versus should desires despite widespread conviction that neediness is the most important criterion for charitable allocations, we observe a “charity beauty premium” in which donors often favor beautiful, but less needy charity recipients. we propose that donors hold simultaneous, yet incongruent preferences of wanting to support beautiful recipients (who tend to be judged as less needy) yet believing they should support needy recipients instead. we additionally posit that preferences for beautiful recipients are most likely to emerge when decisions are intuitive whereas preferences for needy recipients are most likely to emerge when decisions are deliberative. we test these propositions in several ways. first, when a beautiful recipient is introduced to basic choice sets, it becomes the most popular option and increases donor satisfaction. second, heightening deliberation steers choices away from beautiful recipients and toward needier ones. third, donors explicitly state that they “want” to give to beautiful recipients but “should” give to less beautiful, needier ones. taken together, these findings reconcile and extend previous and sometimes conflicting results about beauty and generosity. keywords: prosocial behavior, altruism, decision making, beauty premium, want versus should preferences, intuitive versus deliberative decision making “pandas are among a number of endangered animals that are sometimes classified, not flatteringly, as ‘charismatic megafauna,’ which attract money and attention out of proportion to their numbers. the british naturalist christopher packham once offered to ‘eat the last panda’ if doing so would free up funding for less photogenic species with better chances of survival outside zoos.” owen , attractive donation targets, such as giant pandas, often receive the lion’s share of charitable contributions in the animal world, whereas needier but less photogenic creatures, such as the pygmy sloth, remain neglected (iucn red list ). this is one example of donation patterns that tend to overlook the world’s neediest recipients; for example, of the more than $ billion donated in the united states in , only % went directly to international affairs, a fundraising category that encompasses the developing world where the most pressing human needs exist (giving usa ; unicef ). in this research, we propose one reason why the neediest recipients may be overlooked: donors are swayed by recipient beauty. people naturally ascribe favorable qualities, and grant disproportionate benefits, to beautiful individuals in a phenomenon known as the “beauty premium” (dion, berscheid, and walster ; langlois et al. ). in the prosocial domain, however, a preference for beautiful recipients could lead to puzzling allocation choices. perceptions of beauty and neediness are often negatively correlated (fisher and ma ; langlois et al. ; zaatari, palestis, and trivers ); therefore, a focus on beauty could result in neglect of the neediest individuals. previous research on recipient beauty and charitable giving shows seemingly contradictory patterns: some findings indicate that donors prefer beautiful recipients (mims, hartnett, and nay ; west and brown ), whereas other findings indicate that donors prefer less beautiful, needier recipients (fisher and ma ). in the current research, we attempt to understand the psychology behind both patterns. we posit that donors hold simultaneous, yet incongruent preferences including that they want to give to beautiful recipients but think they should give to needy recipients instead. in line with this notion, we find that when donors make decisions intuitively, their want preference for beautiful recipients emerges, whereas when they make decisions deliberatively, their should preference for needy recipients emerges. as we consider in a final discussion, the present findings allow insight into why the neediest recipients may often not receive priority in the real world. recipient neediness as a criterion for giving proponents of the nascent “effective altruism” movement, including the renowned philosopher peter singer, endorse the notion that donors should allocate their funds to the causes that prevent the most suffering (macaskill ; singer , ). this often means donating to recipients in the developing world, where people’s standards of living are the lowest and the incidence of preventable death is the highest (givewell ; unicef ). recipient neediness does not take precedence in the philosophical realm alone. a similar preference for the neediest recipients emerges from individuals’ explicitly stated donation criteria. we asked mechanical turk participants ( female, male; mage = ) to generate an open-ended answer to the question “if multiple individuals needed help and you http://www.givewell.org/criteria were deciding which one to donate to, what would be the single most important thing you would consider when deciding which person to donate to?” results, coded by research assistants blind to this paper’s hypotheses, showed that % of participants spontaneously answered that recipient neediness was the most important consideration. in comparison, the next most popular consideration was the potential impact of the donation, receiving % of responses; all other possible answers each received less than a % endorsement. despite the common conviction that recipient neediness is the most important consideration for allocations, this criterion does not seem to receive priority in practice. a small fraction of donated dollars go to individuals in life-or-death situations (giving usa ), though many such individuals exist (unicef ). previous research sheds light on several important factors besides recipient neediness that influence donation decisions. these include donors’ sympathy for the recipient (loewenstein and small ; wispé ), donors’ personal experiences (ratner and miller ; small and simonsohn ), donors’ need for emotional satisfaction (andreoni ; cialdini et al. ; dunn, aknin, and norton ), and donors’ desire to maintain a positive image via both social and self-approval (batson ; cain, dana, and newman ). yet another factor that we hypothesize sways donor’s choices away from the neediest recipients is recipients’ aesthetic appeal. this hypothesis stems from research about the “beauty premium,” a phenomenon in which beautiful individuals receive more favorable judgments and benefits than their less beautiful counterparts. the beauty premium in a seminal study, dion, berscheid, and walster ( ) showed that people attribute more positive qualities to attractive than to unattractive others, and more negative qualities to unattractive than to attractive others. this “beauty premium” is confirmed by numerous findings demonstrating that facial attractiveness positively influences judgments by both familiar and unfamiliar perceivers in multiple domains and across cultures (langlois et al. ; miller ). more attractive children and adults are considered to be healthier and fitter, to have greater social appeal, to have higher academic competence, and to be more confident and better adjusted than their less attractive counterparts (landy and sigall ; langlois et al. ; mobius and rosenblat ). more attractive individuals also are more successful in their attempts at persuasion (landry et al. ) and receive sizable wage premiums compared to less attractive individuals (hamermesh and biddle ). there are two dominant explanations regarding why the beauty premium occurs. one explanation is rooted in an evolutionary perspective that centers on reproductive selection and fitness. this evolutionary account proposes that a preference for beauty arises because beauty is a signal of traits such as health, athleticism, and intelligence, which are important for fertility and/or survival (buss and schmitt ; langlois et al. ; mobius and rosenblatt ). a second explanation proposes a more instinctive connection between beauty and favorable judgments. this account suggests that people simply have a taste, or predilection, for beauty even when fitness or beliefs about fitness are unrelated (becker ; hamermesh and biddle ; mulford et al. ; newman and bloom ). such a taste-based preference for beauty has been posited to be automatic and affective at its core (reimann et al. ) and to arise as a by-product of information processing within the human brain (rhodes ). factors that are correlated with attractiveness, such as symmetry, are desirable not just for human faces but for many other stimuli, such as birds and wristwatches (halberstadt and rhodes ; kubovy ). in the consumer domain, this innate draw toward beauty is manifested by favorable responses to aesthetic designs, including a desire to own an attractive product (norman ) and to pay more for it (bloch, brunel, and arnold ), even in categories such as finance for which aesthetics are deemed to be irrelevant (townsend and shu ). an appreciation for beauty not only increases the likelihood that people choose more attractive options but also results in higher satisfaction among people who do so. visually beautiful stimuli activate reward centers in the brain (aharon et al. ), elicit intense positive emotional responses (leder et al. ; reimann et al. ), and generate pleasurable subjective experiences (reber, schwarz, and winkielman ; townsend and sood ). want versus should preferences in charitable giving in the domain of charitable giving, an instinctive and gratifying preference for beauty could lead to puzzling allocation choices. physically attractive people are perceived to be more competent, popular, and successful than their less attractive counterparts (langlois et al. ) and, accordingly, should be perceived as less in need of help. indeed, zaatari, palestis, and trivers ( ) find that proposers in an ultimatum game rate the most attractive respondents as the least needy. similarly, fisher and ma ( ) find that more attractive donation recipients are perceived to be less needy than less attractive recipients. our own data reveal a similar pattern; in a correlational study, mechanical turk participants (n = ) rated of charity recipient photos from a fundraising website on dimensions of attractiveness and neediness. the set of photos included pictures of women and men across a variety of adult ages and ethnicities. we observe a significant negative correlation, r = − , p < . , between ratings of attractiveness and neediness. an instinctive draw to beautiful recipients might therefore be at odds with donors’ explicitly held belief that individuals in the greatest need should receive altruistic priority. in this research, we propose that this incongruence exists because donors simultaneously hold two distinct preferences: a want preference for beautiful recipients and a should preference for needy recipients (bazerman, tenbrunsel, and wade-benzoni ; bitterly, dai, and milkman ; milkman, rogers, and bazerman , ). previous research conceptualizes want preferences as those that are affect-rich and, sometimes, linked with desire (bazerman, tenbrunsel, and wade-benzoni ; loewenstein ) and should preferences as those that are reason-based, logical, and more easily justified (bazerman, tenbrunsel, and wade-benzoni ). for example, when choosing movies, consumers may hold a want preference to watch a comedy but a should preference to watch a documentary (milkman, rogers, and bazerman ). in the charity domain, we hypothesize that if humans have an automatic and gratifying preference for beautiful stimuli, they may intuitively want to give to beautiful charity recipients, even if they deliberately believe that they should give to needy recipients. beautiful recipients offer intuitive appeal and immediate satisfaction, whereas needy recipients fit with a reasoned priority to help the most desperate individuals. we further propose that donors’ want preferences for beautiful recipients are most likely to emerge when they choose intuitively, whereas donors’ should preferences for needy recipients are most likely to emerge when they choose deliberatively. research from a breadth of psychology disciplines recognizes distinctions in cognitive functioning between “system ” processing, or intuitive processing that depends on automatic associations, and “system ” processing, or deliberative processing that depends on logical reasoning (stanovich and west ). processes under system operate quickly, rely on seemingly effortless associations to inform judgments, and tend to favor affect-rich options. processes under system , by contrast, operate slowly and rely on effortful cognition to reach reasoned conclusions (chaiken and trope ; kahneman and frederick ; milkman, chugh, and bazerman ). because preferences for beautiful recipients may arise from automatic, instinctive preferences, we predict that they will be most likely to emerge when donors process information intuitively via system . in contrast, because we posit that preferences for needy recipients arise on the basis of reason, we predict that they are most likely to emerge when donors process information deliberatively via system . these predictions are consistent with previous research implicating a dual-system model of information processing in want versus should preferences (bitterly et al. ; milkman, rogers, and bazerman ). the intuitive system is reward seeking and often oriented toward what feels good, whereas the deliberative system is rule based and oriented toward what is appropriate and sensible (epstein ; shiv and fedorikhin ). understanding a distinction between donors’ intuitively versus deliberately derived preferences could shed light on discrepancies that exist in the altruism literature. some past research finds, for example, that attractive people are more likely to receive help than unattractive people (mims, hartnett, and nay ; west and brown ). in contrast, other research finds that unattractive people are more likely to receive help than attractive people (fisher and ma ). to reconcile these inconsistent findings, we propose that donors hold simultaneous yet contradictory preferences that are cued by different information-processing modes: when donors decide intuitively, they are more likely to select beautiful recipients in line with their want preferences; when donors decide deliberatively, they are more likely to select needy recipients in line with their should preferences. we test these propositions across eight studies. studies a through c explore what happens to donors’ choices and satisfaction when beautiful options are included in basic choice sets, and document a preference for beautiful options. studies through test the proposition that increasing deliberation shifts preferences away from beautiful recipients and toward needy recipients. study examines how very high levels of perceived need, and associated high empathy, weaken the charity beauty premium. finally, study demonstrates that donors’ preferences for beautiful versus needy recipients specifically represent want versus should preferences. throughout, we attempt to understand the psychology underlying donors’ preferences for beautiful versus needy recipients and, in the process, shed new light on previous findings in this domain. study a study a is a field study that solicited donations for an animal conservation center in the uk. the conservation center sells animal adoption packages that include receipt of a paper leaf inscribed with the donor’s name that is placed on the center’s adoption tree. while all species on the conservation center’s website need funds, each species’ conservation status differs because some animals are more critically endangered than others. we test how judgments of beauty and endangerment predict donations to different animal species. pretest one hundred seven university graduate and undergraduate students rated images of eight animals from the conservation center’s adoption webpage on beauty and perceived endangerment ( – scales; please see web appendix a for photos); order of image and question were counterbalanced. table shows rating results as well as each animal’s actual endangerment status as determined by a prominent conservation organization (iucn ). ***** insert table about here ***** main study simulating the conservation center’s adoption packages, a poster featuring a tree was placed in the foyer of a busy university building in the uk. the poster included the message “support [conservation center] today. join our support tree! [conservation center] contributes to animal conservation.” students, staff, and visitors passing by were asked if they would like to donate to support animal conservation. those who were interested viewed a booklet with the animal images from the pretest and chose an animal to support. donors could then write their name on a paper leaf and append the leaf to the poster. the suggested donation amount was pence (approximately $. ) per paper leaf, but donors were free to donate more both to the same animal and to different ones. donations were collected for five consecutive days. results pretest. the giraffe and the zebra were rated the most beautiful and least endangered animals, whereas the penguin and orangutan were rated the least beautiful and most severely endangered; these endangerment ratings were in line with actual endangerment status as determined by the iucn red list ( ; see table ). main study. the giraffe and the zebra, rated the most beautiful animals in the pretest, received a significantly greater percentage of sponsorships than the two least beautiful animals, the penguin and orangutan (which also were correctly perceived as being more severely endangered), % versus % respectively, χ = . , p < . . a similar test comparing sponsorships for the four most beautiful versus least beautiful animals showed that the former were selected significantly more often than the latter ( % versus % respectively, χ = . , p < . ; see figure ). the same test conducted with the four most versus least endangered species, determined either by actual endangerment status or by participants’ ratings of perceived endangerment, showed no such difference (actual endangerment: high = % vs. low = %, χ = . , p = . , perceived endangerment: high = % vs. low = %, χ =. , p = . ). ***** insert figure about here ***** discussion study a provides initial field evidence that beautiful recipients can be preferred even when they do not have the highest need. study b explores this pattern further, incorporating an experimental test. study b study b experimentally tested how adding a beautiful recipient to a basic choice set changes donors’ preferences and satisfaction. all participants viewed images of four children who had received successful cleft palate surgery via the charity smile train, and chose which child they would sponsor. pretest four hundred eighty-one mechanical turk participants ( male, female; mage = ) rated four children on attractiveness (“cuteness”) and neediness. one child (angelica) was rated as significantly cuter than any of the other four children (mangelica = . , mvera = . , mmaria = . , msilva = . , myaolin = . ; ps < . ). angelica also was rated as significantly less needy than the other four (mangelica = . , mvera = . , mmaria = . , msilva = . , myaolin = . ; ps < . ); one child, vera, also consistently was rated as needier than the remaining three children (vs. maria, p < . ; vs. silva, p < . ; vs. yao lin, p < . ). main study method. three hundred sixty mechanical turk participants ( female, male, mage = ) participated in exchange for a small payment. participants were presented, in random order, with the pretested pictures of four children who had been helped by smile train and read that these children needed financial support to move on with their lives after cleft palate surgery. the children were described as approximately the same age ( – years) and from the same region of the world (central and south america). the experiment included control and beauty conditions. in the control condition, participants viewed the four children who, according to the pretest, were similar in attractiveness (vera, maria, silva, and yao lin). in the beauty condition, the child rated as significantly more beautiful and less needy than the others, angelica, was substituted for yao lin; to maintain experimental control, the name “angelica” was used in both conditions. participants then selected a child as if they were actually sponsoring her. next, they answered follow-up questions about how happy, pleased, and content they felt as a result of their choice; these items were combined into a single “satisfaction” score (α = . ). results. an omnibus chi-square test revealed a significant difference between conditions in sponsorship choices, χ ( , n = ) = . , p < . (see figure ). participants in the control condition, who did not consider a clearly beautiful option, showed a preference for vera, the neediest child, over all others (vera, %; maria, %, p = . ; yao lin, %; p < . ; silva, %, p < . ; all p-values relative to vera’s choice share). ***** insert figure about here ***** results differed in the beauty condition. participants in the beauty condition, who instead of yao lin considered angelica, the most beautiful and least needy child according to the pre-test, chose angelica more often than any other child (angelica = %, vera = %, p = . ; maria = %, p < . ; silva = %, p < . ; all p-values relative to angelica’s choice share). in this beauty condition, compared to control, participants also were less likely to choose vera, the child perceived as the neediest ( % vs. %, z( ) = . , p < . ). in addition to selecting angelica more often than any other option, participants in the beauty condition reported greater satisfaction with their choice than did those in the control condition, mbeauty = . , mcontrol = . , t( ) = . , p < . . discussion results from study b are consistent with several past findings about beauty and generosity (mims, hartnett, and nay ; west and brown ): when a beautiful recipient is present, donors are more generous toward that beautiful recipient. further, we observe that not only do donors choose a beautiful recipient when one is present, but they also are more satisfied with their choice, supporting the notion that beauty is gratifying. in contrast, when no beautiful option is present, donors gravitate toward the neediest recipient, in line with their explicit prioritization of neediness. study c continues to explore this pattern with novel stimuli and decision types. study c study c tests donors’ reactions to recipients who are more beautiful versus less beautiful using a different approach from study b. donors in study c viewed a single recipient instead of several, considered donating to an adult instead of to a child, considered a photo of the same person that had been edited via photo software to be more versus less beautiful, and made real donations. the new study design also allowed follow-up questions measuring perceptions of facial expression so that we could control for this factor. pretest pretest participants recruited from mechanical turk (n = ; female, male, one gender unknown; mage = ) rated a photo of either a man (“evan”) or a woman (“andrea”) from a fundraising website. in the beauty condition, participants saw the original, attractive, photo of one of these two individuals. in the control condition, the photos were edited, introducing asymmetries to make them less attractive. participants were randomly assigned to view one of the four photos. each participant rated the photo on the same dimensions (beauty/handsomeness and neediness) used in study b, using -point scales. the two beauty condition photos were rated more “beautiful or handsome” (andrea: mbeauty = . , mcontrol = . , t( ) = . , p < . ; evan: mbeauty = . , mcontrol = . , t( ) = . , p < . ) and less needy (andrea: mbeauty = . , mcontrol = . , t( ) = . , p < . ; evan: mbeauty = . , mcontrol = . , t( ) = . , p < . ) than the two control condition photos. main study method. two hundred thirty-eight adults ( female, male; mage = ) participated online via mechanical turk. after reading initial instructions, participants learned that they would receive a -cent bonus that they could donate to charity as part of the study. the study included two between-subjects experimental conditions (control, beauty) with recipient gender randomized within each condition. all participants read that they could donate to a recovered bone cancer patient who was seeking financial help. in the beauty condition, participants saw the original photo of either an attractive man or an attractive woman from a fundraising website. in the control condition, participants saw an edited, less attractive version of the same man or woman. donors decided whether to donate their $. bonus to the recipient or not. following procedures from study b, participants then rated how happy, pleased, and content they felt as a result of considering the donation request (“satisfaction” score α = . ) as well as how happy, sad, needy, and beautiful the recipient looked. results. participants were more likely to donate in the beauty condition ( %) than in the control condition ( %, χ ( , n = ) = . , p < . ). this effect did not differ between female and male photos (p > . ); moving forward we collapse results across recipient gender. the beauty effect remained significant when controlling for the recipient’s judged happiness, sadness, neediness, or all three measures at once (in simultaneous logistic regressions, ps < . ). when controlling for perceived beauty of the recipient, however, the effect of beauty became non-significant (p > . ); this result is consistent with the notion that perceived beauty, but not facial expression, drives donation differences between the beauty and control conditions. a simultaneous mediation analysis confirmed that perceived beauty uniquely accounted for the influence of beauty on donations. we conducted a bootstrapping mediation analysis with , samples using hayes’s ( ) process macro (model ), which included measures of perceived happiness, sadness, neediness, and beauty. only perceived beauty significantly mediated the relationship between the beauty condition and donation choice, % ci = . –. . in this model, the direct effect was no longer significant (p = . ), and no other potential mediators were significant (ps > . ). we note that this particular mediation analysis does not suggest a psychological mediator for the charity beauty premium (zhao, lynch, and chen ) but instead serves as a rigorous manipulation check. participants also reported marginally significantly greater satisfaction in the beauty condition than in the control condition (mbeauty = . , mcontrol = . , t( ) = . , p < . ). a simultaneous mediation model analogous to the one described above confirmed that perceived beauty uniquely accounted for the influence of the beauty condition on satisfaction, % ci = . –. . in this analysis, the direct effect was no longer significant (p = . ), and no other potential mediators, including facial expression, were significant. discussion in study a, donors were more likely to sponsor beautiful animals, even when beautiful animals were not the most endangered. in study b, donors selected the neediest child as long as a beautiful (but less needy) recipient was not an option; once a beautiful recipient was an option, she became the most popular recipient and increased donor satisfaction (see also web appendix b). in study c, this preference for a beautiful recipient, and the subsequent greater donation satisfaction, persisted when participants made real donations to a single adult recipient, and it was not explained by recipients’ facial expression. although a preference for beautiful recipients is consistent with some prior evidence about beauty and giving (mims, hartnett, and nay ; west and brown ), it is not consistent with donors’ explicit statements (reported in our initial survey) that neediness is the most important criterion for charitable allocations. it is also not consistent with recent evidence that finds the opposite pattern, namely, that less attractive recipients receive more donations (fisher and ma , study ). a common feature of studies a through c is that participants’ decisions were relatively intuitive. studies a and b involved a sponsorship selection from a small set of pictures; study c included a simple yes/no choice of whether to donate a bonus payment. previous research documenting a beauty premium in prosocial domains also relied on choices that are likely intuitive, such as whether agreeing or not to help an attractive, versus unattractive, experimenter with an additional task (mims, hartnett, and nay ). in this research, we propose that intuitive versus deliberative decision modes can lead to diverging recipient preferences. more specifically, we hypothesize that intuitive processing leads to preferences for beautiful recipients whereas deliberative, cognitively effortful processing leads to preferences for needy recipients. studies through directly test this hypothesis. study study tests whether intuitive versus deliberative decision modes influence the charity beauty premium by directly asking participants to let either deliberation or intuition guide a charity recipient choice. we predict that when deciding intuitively, participants will prefer the most beautiful recipient, but when deciding deliberatively, they will not. method. two hundred forty mechanical turk participants ( female, male; mage = ) participated online in exchange for a small payment. participants first read the scenario from study b. in the intuitive condition, participants also read, “please make a quick choice, letting intuition guide which child you would sponsor. be sure to rely on your instincts.” in the deliberative condition, participants read, “please think carefully about your choice, thoroughly considering which child you would sponsor. be sure to rely on logical deliberation.” all participants then viewed the photos from the beauty condition from study b (excluding any additional text such as names). participants first chose a child to sponsor and then rated to what extent their sponsorship choice was based on intuition versus deliberation ( – rating scale with = “entirely on intuition” and = “entirely on deliberation”). we also measured participants’ response time from when they loaded the survey screen with recipient photos until they made the final decision click on the same screen. results manipulation checks. participants in the deliberative condition indicated that their choice was based more on deliberation than did participants in the intuitive condition (mdeliberative = . , mintuitive = . , t( ) = . , p < . ). response time in seconds also was higher in the deliberative condition than in the intuitive condition (meddeliberative = . , medintuitive = . , mann-whitney u = , , p < . ). main results. an omnibus chi-square test revealed a marginally significant difference between conditions in sponsorship choices, χ ( , n = ) = . , p = . (see figure ). participants in the intuitive condition showed a preference for angelica, the most attractive and least needy of the four children according to the study b pre-test (angelica, %; vera, %, p < . ; maria, %, p < . ; silva, %, p < . ; all p-values relative to angelica’s choice share). ***** insert figure about here ***** in the deliberative condition, angelica was no longer a favorite (angelica, %; vera, %, p = . ; maria, %, p < . ; silva, %, p = . ; all p-values relative to angelica’s choice share). in the deliberative condition, compared to the intuitive condition, participants were less likely to choose angelica, the most beautiful and least needy recipient, for their allocation decision ( % vs. %, z( ) = . , p < . ); consequently, they were more likely to choose needier recipients. discussion in study , when donors decided intuitively, they were most likely to choose a beautiful recipient; however, an explicit request to choose deliberatively eliminated this preference. in the deliberative condition, preferences shifted toward the less beautiful, but needier, recipients instead, providing initial evidence that the charity beauty premium emerges from intuitive, but not deliberative, decisions. study in study , we use an alternative method to manipulate deliberation. we draw upon findings that decision makers rely more heavily on logic and deliberation when they make choices for others compared to when they make choices for themselves. for example, consumers are less loss averse when choosing for others than when choosing for themselves (polman ), and they seek greater variety when choosing for others because it is a more objectively compelling strategy (choi et al. ; ratner and kahn ). in study , we manipulate whether donors make a sponsorship choice for themselves or on behalf of someone else while serving as an adviser. we predict that asking donors to serve as advisers, and thus choosing on behalf of someone else, will encourage them to override intuitive preferences for beauty in favor of deliberative preferences for neediness. method two hundred sixty-four participants from mechanical turk ( female, male; mage = ) participated online in exchange for a small payment. participants read the scenario from study b. in the intuitive condition, participants chose one child to support as a sponsor. in the deliberative condition, participants served as an adviser, choosing “which child will be sponsored by an anonymous donor.” all participants viewed the same pictures and short recipient descriptions from the beauty condition from study b and chose a child, in the role either of sponsor (intuitive condition) or adviser (deliberative condition). results an omnibus chi-square test revealed a difference between conditions in sponsorship choices χ ( , n = ) = . , p = . (see figure ). participants in the intuitive condition sponsored angelica, the most attractive and least needy of the four children, most often (angelica, %; vera, %, p < . ; mariana, %, p = . ; silva, %, p < . ; all p-values relative to angelica’s choice share). ***** insert figure about here ***** in the deliberative condition, in which participants served as an adviser, angelica was no longer the favorite (angelica, %; vera, %, p = . ; mariana, %, p < . ; silva, %, p < . ; all p-values relative to angelica’s choice share). in the deliberative condition, compared to the intuitive condition, participants were less likely to choose angelica for their allocation decision ( % vs. %, z( ) = . , p < . ), and they were also more likely to choose vera, the neediest child ( % vs. %, z( ) = . , p < . ). in a posttest, we verified that making sponsorship choices on behalf of someone else prompts deliberation compared to making sponsorship choices for oneself. previous research has shown that accountability to others can heighten expectations of justifying one’s decision (lerner and tetlock ) and induce controlled information processing (bazerman et al. ). thus, we asked mechanical turk participants to read either the intuitive or the deliberative scenario and to rate the extent to which they would expect to need to justify the decision to others. participants who read the deliberative condition scenario were more likely to anticipate justifying their choice than were participants who read the intuitive condition scenario (mdeliberative = . , mintuitive = . , t( ) = . , p < . ). discussion in study , donors who were placed in a more deliberative state by serving as advisers were less likely to choose angelica, the most attractive but least needy recipient. these participants also were more likely to act in line with an explicit prioritization of neediness by choosing vera, the child who was rated as needier than the others. we note that the current result is incompatible with the notion that donors choose beautiful recipients because beautiful individuals are more worthy or more promising. if expectations of beautiful recipients’ success drive the charity beauty premium, then we should observe it both when participants make sponsorship choices for themselves and when they make sponsorship recommendations to others. however, we observe that when participants serve as advisers, the charity beauty premium weakens and, in fact, reverses; this pattern is consistent with an account that donors prefer beautiful recipients because of an intuitive preference for aesthetic appeal and not because these recipients are justified to be more likely to succeed. study tests an additional way of increasing deliberation: asking participants to rate recipients on several dimensions before making sponsorship choices. study previous research documenting that donors allocate more funds to less attractive, needier recipients than to more attractive, less needy recipients finds this pattern after participants first explicitly rate charity recipients on several dimensions including neediness, attractiveness, and empathy (fisher and ma , study ). it is possible that such a rating task encourages participants to thoroughly consider recipients, prompting deliberative decision making. in study , we directly manipulate whether such a rating task steers donors toward a deliberative choice of needy recipients and away from an intuitive choice of beautiful recipients. study includes an intuitive condition identical to that in study and also includes a new deliberative condition in which, before making sponsorship choices, participants explicitly rate each recipient on dimensions identical to those measured by fisher and ma ( ): attractiveness, emotional expression, social competence, perceived need, and empathy. method three hundred six mechanical turk participants ( female, male; mage = ) completed the study in exchange for a small payment. the experiment included two conditions: the intuitive condition from study and a new deliberative condition in which participants rated each child on attractiveness (three items, -points scales), emotional expression (four items, - point scales), social competence (seven items, -point scales), perceived need (four items, - points scales), and empathy (five items, -point scales), all following procedures used by fisher and ma ( ), before making their sponsorship choice. results rating results. similar to the pretest described before study b, participants in the deliberative condition, who rated each child on multiple dimensions before making the allocation choice, rated angelica as more attractive (mangelica = . , mvera = . , mmaria = . , msilva = . , ps < . ) and less needy (mangelica = . , mvera = . , mmaria = . , msilva = . , ps < . ) than any of the other three children; they also judged vera to be needier than any of the other three children, ps < . ). in addition, participants reported either directionally or significantly less empathy for angelica (mangelica = . , mvera = . , p < . ; mmaria = . , p = . , msilva = . , p = . ) and significantly more empathy for vera compared to the other children (ps < . ). these empathy ratings are consistent with the central finding from fisher and ma ( , studies – ) that participants express more empathy for a less beautiful than for a more beautiful charity recipient. main results. an omnibus chi-square test showed a difference between conditions when choosing which child to support, χ ( , n = ) = . , p < . (see figure ). ***** insert figure about here ***** in between-subjects comparisons, participants in the deliberative condition were less likely to choose angelica, the most beautiful recipient, than were participants in the intuitive condition ( % vs. %, z( ) = . , p < . ), and more likely to choose vera, the neediest recipient ( % vs. %, z( ) = . , p < . ). within the deliberative condition, vera was selected the most frequently (vera, %; angelica, %, p < . ; mariana, %, p < . ; silva, %, p <. ; all p-values relative to vera’s choice share), whereas within the intuitive condition, angelica was selected the most frequently (angelica, %; vera, %, p = . ; maria, %, p < . ; silva, %, p < . ; all p-values relative to angelica’s choice share). discussion the deliberative condition from study demonstrates that a rating task, which prompts a thorough consideration of each recipient, pushes donors to choose needier, less beautiful, recipients. this study also sheds light on previous results by showing that such a rating task can trigger a reversal of the charity beauty premium (fisher and ma ; study ). although donors gravitate toward beautiful recipients when choices are intuitive, increasing deliberation by asking participants to rate recipients on several attributes (including both beauty and neediness) steers them to allocate in accordance with their explicit priority of neediness. across studies through , donors were more likely to choose beautiful recipients when deciding intuitively and needy recipients when deciding deliberatively. rating results from study also show that participants report greater empathy for a less beautiful than for a more beautiful recipient. this result is consistent with the central finding from fisher and ma ( , studies – ). despite greater empathy for less beautiful recipients, however, we find that donors choose these recipients only when the choice is deliberative, but not when the choice is intuitive. in the next study, we further explore the complex role of empathy in the relationship between donors’ preferences for beautiful versus needy recipients. study study explores the role of empathy in the charity beauty premium. in study , we see that empathy only predicts giving when participants process information in a deliberative, system mode. in many respects, this result is puzzling. empathy and sympathy are often presumed to be affective responses and, therefore, associated with system intuitive processing (batson ; loewenstein and small ). yet, empathy and sympathy are unique affective influences, because they also often correlate with deliberative judgments of neediness (batson et al. ; fisher and ma ; study ratings from the current paper). moreover, past research proposes a deliberative component of such sympathetic emotions (hatfield, cacioppo, and rapson ). according to this account, empathy entails taking another person’s perspective, a process involving reflection and effort (wispé ) that relies on deliberative cognition. this characterization of empathy is consistent with our findings thus far that donors are more likely to favor empathetic recipients when processing deliberatively. nevertheless, empathy and sympathy have potential to activate intense affective responses as well. such intense affective responses may actually oppose, and even overwhelm, donors’ intuitive want preference for beauty. we posit that very high levels of need may trigger strong emotional empathy toward recipients (loewenstein and small ; small and cryder ), which in turn can override beauty preferences due to a competing system influence. we test this hypothesis in study . method seven hundred seventy mechanical turk participants ( female, male; mage = ) participated in exchange for a small payment. similar to study c, participants learned that they would receive a -cent bonus that they could donate to charity during the study. the study included a (photo: control, beautiful) × (empathy: control-empathy, high-empathy) between-subjects experimental design. the beautiful versus control photo manipulation was identical to that in study c (randomizing female and male photos within condition). in the control-empathy condition, participants read the recipient description from study c portraying a recipient who has recovered from bone cancer and is seeking financial help to move forward in life. in the high-empathy condition, the recipient was described as even higher in need, struggling to recover from bone cancer and no longer able to work and support a family (please see web appendix c for full wording). as in study c, the main dependent variable was whether participants decided to donate their participation bonus to the recipient or not, after which they responded to five items from fisher and ma ( ; see also study of the current paper) designed to measure empathy: the extent to which participants felt sympathetic, compassionate, softhearted, warm, and moved ( – point scales, items combined for single empathy score, α = . ). results manipulation check. participants in the high-empathy condition reported greater empathy than did participants in the control-empathy condition (mhighempathy = . , mcontrolempathy = . , t( ) = . , p < . ). main results. a binary logistic regression simultaneously tested the influence of beauty, empathy, and their interaction on donation likelihood. we observed a marginally significant positive main effect of beauty, exp(b) = . , p = . , and a significant positive main effect of empathy, exp(b) = . , p < . . most importantly, we observed a significant interaction between beauty and empathy, exp(b) = . , p < . . within the control-empathy condition, participants who saw a beautiful photo were marginally significantly more likely to donate ( %) than those who saw a control photo ( %, χ ( , n = ) = . , p = . ), replicating study c’s findings. within the high-empathy condition, however, participants who saw a beautiful photo were not more likely to donate ( %) than were participants who saw a control photo ( %; χ ( , n = ) = . , p > . ). to more firmly understand the phenomenon from study , we showed a new set of mechanical turk participants (n = ) the high empathy description from study and told them that it prompted many people to donate. participants then indicated whether they thought people donated because of ) logical thoughts that the person was needy, ) emotional reactions to the person’s situation, or ) other reasons (with an option to type a response; the order of the first two response options was counterbalanced). a strong majority, %, of participants indicated that emotional reactions drove the response, providing evidence that the high-empathy manipulation was indeed an affective, system –based manipulation. discussion in study we observe that, when faced with recipients in severe need, donors experience high empathy and a tendency to help regardless of beauty. this result complements that from fisher and ma ( ) showing that when recipient need and donor empathy are high, donors feel compelled to help regardless of recipient beauty. in both sets of findings, empathy overwhelms beauty; however, we note that the natures of these two findings differ. in the case of fisher and ma ( , p. ), high empathy trumps a system deliberative process that favors less beautiful recipients; in the present study, high empathy trumps another system process, an instinctive preference for beauty. we therefore have found that multiple preference patterns can result from intuitive system processing; first, we have observed an instinctive draw toward beauty that leads to feelings of happiness and satisfaction (studies b and c); second, we have observed that very high levels of empathy can push donors to choose needy recipients, regardless of their beauty (study ). because there are multiple types of preferences that can arise from intuitive (versus deliberative) decisions, in a final study we test whether beautiful versus needy recipients specifically represent donors’ want versus should preferences. study in studies through donors were more likely to choose beautiful recipients when deciding intuitively but more likely to choose needy recipients when deciding deliberatively. however, there are multiple types of preference patterns that can result from intuitive (vs. deliberative) decision modes (morewedge and kahneman ; stanovich ), including, for example, stronger sensitivity to affect-rich options (rottenstreich and hsee ) or greater sensitivity to emotional influences like empathy (loewenstein and small ). in study , we test whether donors’ preferences for beautiful versus needy recipients map onto their want versus should desires respectively. method two hundred and forty-eight mechanical turk participants ( female, male; mage = ) participated in the study online in exchange for a small payment. participants viewed the sponsorship scenario and photos from the beauty condition from study b and then answered two questions on the same page: “which one of these children do you think the donors would want to choose?” and “which one of these children do you think the donors should choose?” (the words “want” and “should” were bolded in the actual questions; cf. milkman, rogers, and bazerman ). results a within-subjects omnibus mcnemar-bowker test showed a difference between conditions in which child was selected, χ ( , n = ) = . , p < . . when participants considered which child donors want to give to, they chose angelica ( % of choice share), the most attractive and least needy child (vera %, maria %, silva %, all ps < . relative to angelica’s choice share; see figure ). results were different when participants considered which child donors should give to. with this question, angelica was no longer the most frequent choice, now only receiving % of choice share, whereas vera, who was previously rated as needier than the other children, was chosen the most frequently (vera, %; maria, %; silva, %; all ps < . relative to vera’s choice share). in between-questions analysis, participants were more likely to choose angelica when answering the “want” compared to “should” question ( % vs. %, z( ) = . , p < . ); participants were more likely to choose vera when answering the “should” compared to “want” question ( % vs. %, z( ) = . , p < . ). ***** insert figure about here ***** discussion study lends direct support to the idea that donors choose beautiful charitable recipients to satisfy want preferences whereas they choose needy charitable recipients to satisfy should preferences. when asked which recipient donors want to choose, participants selected angelica (the most beautiful, least needy recipient) most often, whereas when asked which recipient donors should choose, they selected vera (the neediest recipient) most often. participants were naturally able to express charity recipient preferences in want and should categories. we also once again see evidence that the charity beauty premium cannot be attributed to beliefs that beautiful recipients have more potential than their less beautiful counterparts (langlois et al. ). if beliefs about recipient success drive the charity beauty premium, then participants ought to indicate that they should give to beautiful recipients. instead, participants indicate that they should give to needier, but less beautiful, recipients instead. general discussion donors explicitly endorse neediness as a top donation priority; however, we observe that they often choose beautiful, less needy recipients instead. we test a hypothesis that donors simultaneously hold a want preference to give to beautiful recipients and a should preference to give to needy recipients. we further test whether preferences for beautiful recipients are most likely to emerge when decisions are intuitive whereas preferences for needy recipients are most likely to emerge when decisions are deliberative. in studies a through c, when beautiful recipients are included in donation recipient choice sets, they are chosen most frequently and increase donor satisfaction. in studies through , prompting deliberative, compared to intuitive, decision making eliminates the charity beauty premium and directs donors toward the neediest recipients. in study , we observe that inducing high levels of empathy for all recipients can overwhelm the charity beauty premium. finally, in study , we find that the precise nature of donors’ preferences for beautiful versus needy recipients corresponds with their want versus should desires: participants explicitly state that donors want to give to beautiful recipients but at the same time that they should give to less beautiful, needier ones. it seems that donors hold both sets of preferences, and that contextual factors favoring intuitive versus deliberative processing drive which preferences they will act upon. the present research reconciles seemingly contradictory previous findings about beauty and giving. although a charity beauty premium is consistent with some past research showing a positive effect of beauty on helping (mims, hartnett, and nay ; west and brown ), recent research uncovered a negative effect of beauty on empathy and helping (fisher and ma ). we bring this work together by identifying the circumstances under which each pattern occurs: when decisions are intuitive, attractive recipients receive more help; when decisions are deliberative, unattractive recipients receive more help. our findings suggest that when donors decide intuitively, charities may benefit by using beautiful photos, whereas when donors decide deliberatively, charities may benefit by emphasizing recipient neediness instead. intuitive system processing often is considered to be the default decision mode, routinely guiding thoughts and actions that are accepted by the deliberative system when processing under low effort (evans and stanovich ; kahneman ). a frequent predominance of intuition over deliberation, in combination with the present findings, sheds light on why needy recipients may be neglected in the real world; if donors predominantly process information intuitively, beauty is likely to be favored. further, these patterns suggest that charities might be best off using beautiful photos as a default unless they believe their donors will be particularly deliberative when choosing (though we emphasize that all organizations should test patterns amongst their own donors and donation contexts). study identifies a situation when system processing does not result in a charity beauty premium: when emotional empathy is high, donors no longer prefer beautiful recipients. although one reaction to this finding is that beauty might have minimal influence in the real world because of an overriding influence of strong empathy, we caution against such an interpretation. first, as we mention in our introduction, real world donations show that the highest-need causes, which have potential to trigger high levels of empathy, do not receive a substantial share of charitable contributions (giving usa ). second, empathy and sympathy are often characterized as negative emotional states (cialdini et al. ; small and verrochi ) and recent neuroimaging research that predicts real world giving finds stronger effects of positive rather than negative donor emotional responses (genevsky and knutson ; genevsky, et al. ). finally, recent field evidence suggests that donors may be adept at avoiding situations where they expect to feel high empathy. a fascinating field study showed that when salvation army solicitors working outside stores made a direct plea to potential donors, looking them in the eye and asking “please give today,” donations increased. however, at the same time, traffic patterns into and out of the stores where solicitors operated also changed so that potential donors avoided encountering the solicitor altogether (andreoni, rao, and trachtman ). these results and others suggest that, once potential donors’ attention is captured, high empathy appeals can be effective (dickert and slovic ); however, when given the opportunity, potential donors may actively attempt to avoid often uncomfortable empathetic appeals. an additional preliminary study that we conducted sounds a cautionary note about increasing deliberation to encourage donors to choose the neediest recipients. in this study, designed similarly to study , participants were randomly assigned to an intuitive condition in which they simply chose a recipient to sponsor, or a deliberative condition in which they rated each potential recipient on neediness before selecting one to sponsor. as in study , the deliberative condition effectively prompted donors to select a needier, less beautiful recipient compared to the intuitive condition. however, later in the same session we asked participants to predict how much they would donate to the overall charity organization one year from now. deliberative condition participants indicated that they would donate significantly less money one year from now compared to those in the intuitive condition, who had been more likely to initially choose beauty. in other words, participants who were prompted to choose needy recipients over beautiful ones did so, but showed less willingness to donate in the future. deliberation, therefore, appears to be a double-edged sword in that it increases priority for the neediest causes in the short term but may decrease kindness in response to future requests. choosing in favor of neediness might satisfy a deliberative priority but might also diminish the immediate gratification that individuals derive from their want charity choices, suppressing future generosity. taken together, this evidence again tentatively suggests that charities might benefit by relying on beautiful photos unless they have a specific reason to believe their donors decide deliberatively when donating. in conclusion, scholars have attempted for many years to understand the puzzle of why highly important campaigns remain underfunded while other, less desperate ones receive an outpouring of support. one of the most notable insights from this research is that focusing on the large scope of a problem, a natural way to present the world’s neediest causes, can undermine fundraising efforts by blocking donors’ capacity for sympathy (kogut and ritov ; small, loewenstein, and slovic ; smith, faro, and burson ) and by obscuring a donor’s sense of impact (cryder, loewenstein, and scheines ; grant ). in this research, we posit another reason why donors do not favor the world’s neediest recipients: they are drawn to beautiful and pleasing ones instead. we examine donors’ intuitive preference for beauty and find that it represents a want desire to give to instinctively pleasing targets. we posit that multiple other want charity preferences exist as well, including preferences to give to 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(. ) least concern ( ) . (. ) zebra . (. ) least concern ( ) . (. ) flamingo . (. ) near threatened ( ) . (. ) elephant . (. ) endangered ( ) . (. ) chimpanzee . (. ) endangered ( ) . (. ) lemur . (. ) endangered ( ) . (. ) orangutan . (. ) endangered ( ) . (. ) penguin . (. ) vulnerable ( ) . (. ) figure study a: percentage of sponsorships for the most and least beautiful animals % % % % % % % % % % % % % % % least beautiful animals most beautiful animals s p o n s o rs h ip a ll o c a ti o n s chimpanzee elephant flamingo giraffe lemur orangutan penguin zebra figure study b: percentage of allocations received by each child based on control versus beauty condition **p < . ***p < . % % % % % % % % % % % vera maria silva angelica/yaolin d o n a ti o n a ll o c a ti o n s beauty control ** *** figure study : percentage of allocations received by each child based on intuitive versus deliberative condition **p < . % % % % % % vera maria silva angelica d o n a ti o n a ll o c a ti o n s intuitive deliberative ** figure study : percentage of allocations received by each child based on intuitive versus deliberative condition *p < . % % % % % % vera maria silva angelica d o n a ti o n a ll o c a ti o n s intuitive (self) deliberative (adviser) * * figure study : percentage of allocations received by each child based on intuitive versus deliberative condition *p < . ***p < . % % % % % % vera maria silva angelica d o n a ti o n a ll o c a ti o n s intuitive (control) deliberative (rating) *** * figure study : choices based on want versus should preferences ***p < . % % % % % % % vera maria silva angelica r e c ip ie n t c h o ic e should want *** *** small is beautiful? explaining resident satisfaction in swedish nursing home care research article open access small is beautiful? explaining resident satisfaction in swedish nursing home care douglas spangler * , paula blomqvist , ylva lindberg and ulrika winblad abstract background: resident satisfaction is an important aspect of nursing home quality. despite this, few studies have systematically investigated what aspects of nursing home care are most strongly associated with satisfaction. in sweden, a large number of processual and structural measures are collected to describe the quality of nursing home care, though the impact of these measures on outcomes including resident satisfaction is poorly understood. methods: a cross-sectional analysis of data collected in two nationally representative surveys of swedish eldercare quality using multi-level models to account for geographic differences. results: of the factors examined, nursing home size was found to be the most important predictor of resident satisfaction, followed by the amount of exercise and activities offered by the nursing home. measures of individualized care processes, ownership status, staffing ratios, and staff education levels were also weakly associated with resident satisfaction. contrary to previous research, we found no clear differences between processual and structural variables in terms of their association with resident satisfaction. conclusions: the results suggest that of the investigated aspects of nursing home care, the size of the nursing home and the amount activities offered to residents were the strongest predictors of satisfaction. investigation of the mechanisms behind the higher levels of satisfaction found at smaller nursing homes may be a fruitful avenue for further research. keywords: nursing home, eldercare, quality, satisfaction, sweden background the increasingly elderly population in many western countries has created an increased demand for high quality medical and social care services. this includes nursing home (nh) care, referring to facilities providing -h functional support and care for persons who re- quire assistance with activities of daily living and who often have complex healthcare needs [ ]. achieving quality in nh care is complicated by the fact that care quality is multifaceted, difficult to define and measure, and may be perceived differently by different stake- holders [ ]. regulatory agencies thus often struggle to identify factors most important in achieving high-quality nh care [ ]. a particular challenge in regulating quality in nh care is that it is in many regards a ‘soft’ service in which the individual experiences of the nh residents is an import- ant dimension of quality. while many aspects of quality (e.g, clinical quality and cost effectiveness) must be con- sidered in order to achieve a well-rounded assessment of the care provided at a given nursing home, some scholars have argued that resident satisfaction may be the most appropriate assessment of quality in nh care [ , ]. in health care, investigations of patient satisfaction are abundant [ , ], while studies measuring nh resi- dent satisfaction are less common. this may be due to the suggestion that elderly patients with cognitive weak- nesses have difficulty reliably answering surveys [ ], though studies have shown that patients in cognitive de- cline are capable of answering surveys, particularly if they are designed with their needs in mind [ – ]. given that the satisfaction of residents is an important dimension of quality in nh care, the question becomes how this is achieved. that is to say, what factors are most important to focus on when seeking to improve © the author(s). open access this article is distributed under the terms of the creative commons attribution . international license (http://creativecommons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. the creative commons public domain dedication waiver (http://creativecommons.org/publicdomain/zero/ . /) applies to the data made available in this article, unless otherwise stated. * correspondence: douglas.spangler@pubcare.uu.se department of public health and caring sciences, uppsala university, box , uppsala, sweden full list of author information is available at the end of the article spangler et al. bmc health services research ( ) : https://doi.org/ . /s - - - http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf http://orcid.org/ - - - http://creativecommons.org/licenses/by/ . / http://creativecommons.org/publicdomain/zero/ . / mailto:douglas.spangler@pubcare.uu.se the satisfaction of nh residents? the most commonly used analytical framework for understanding how quality is generated in health and social care is donabedian’s structure – process – outcome model [ , ]. a central distinction in donabedian’s model is that between struc- tural and processual quality factors, which are seen as potential explanatory factors behind quality outcomes. structural factors refer to the physical attributes of the setting in which care is provided, including the number and qualifications of staff, equipment, and physical facil- ities [ ]. processual factors denote the manner in which the care services are delivered, e.g. whether care routines follow set guidelines, and the extent to which residents are involved in decisions about their care. quality out- comes can be measured in many ways, both objectively in the form of health status or subjectively in the form of patient/resident satisfaction [ ]. a central unresolved question posed in donabedian’s work is whether struc- tural or processual measures are most important for generating outcome quality, and precisely how these fac- tors interact to produce the desired outcomes. the literature on medical quality in nh care in terms of, for instance, mortality and adverse event rates, has investigated numerous explanatory factors including staffing, ownership, care routines, and the size of facil- ities [ – ]. such studies are particularly abundant in the united states, where collection of the minimum data set provides a robust basis for performing broad studies of clinical outcomes. there are considerably fewer investigations of the determinants of resident sat- isfaction. previous studies have investigated structural factors including staff satisfaction [ ], and job commit- ment [ ], with both studies finding positive associations with resident satisfaction. a broader study of the influ- ence of organizational factors found that nh ownership, staffing levels, and the provision of family councils were important predictors of nh resident satisfaction [ ]. others have investigated specific interventions related to processual quality factors such as improved meal time routines [ ], “person-centered care” initiatives [ ], and social activity programs such as gardening [ ]. while generally finding positive effects on resident satisfaction, these interventional studies are narrow, and differ in terms of setting and methodology, making them difficult to compare. taken together, the prior literature on what factors are associated with resident satisfaction in nhs is largely limited to evaluations of specific interventions, and there are few studies investigating the relative influ- ence of structural and processual factors, particularly in the european context. in sweden, several public investigations have pointed to quality deficiencies, and a lack of system- atic knowledge about factors leading to improved quality [ , ]. the issue of nh care quality has increased in significance in swedish public debate as reforms have led to an increasing number of homes contracted out by local governments (municipalities) to private, often for-profit firms. in , one study found that about one fifth of the swedish nhs were run by for-profit providers [ ]. this study, as well as another recent investigation of danish nhs, found that overall, privately operated homes outperformed public and non-profit homes in terms of process mea- sures, while underperforming in terms of structural measures [ , ]. neither of these studies investi- gated resident satisfaction however. in sweden, there is good availability of data on vari- ous aspects of nh care due to comprehensive data col- lection efforts by the swedish national board of health and welfare (nbhw). annual surveys measuring satis- faction are sent by the nbhw to all nh residents, and surveys assessing processual and structural measures of quality are sent to every nh in sweden. so far however, the use of these data for research has been limited. one exception is a study by kajonius and kazemi [ ] which investigated differences in satisfaction among nh resi- dents at the municipal level, finding that processual quality factors such as respect and access to informa- tion appeared to be more important for residents than structural factors such as staffing and budget. in this study, we aim to evaluate which structural and processual measures of quality have the strongest associations with overall nh resident satisfaction. in doing so, we hope to provide policymakers and re- searchers with a broader picture of the determinants of resident satisfaction as nhs than has previously been available. methods setting in sweden, all citizens have access to publicly funded nh services at heavily subsidized rates. the eldercare system in sweden is decentralized, with responsibility for service provision resting with the nation’s mu- nicipalities. municipalities are obliged to offer nh care to those determined to have a need for such care based on national criteria. the municipality may provide ser- vices themselves, or contract out service provision to private entities [ ]. in , there were in total , individuals [ ] living in ca. nhs in sweden [ ], with . % of residents living in nhs operated by pri- vate providers [ ]. while marketization reforms have led to an increase in the proportion of privately man- aged nhs, they remain publicly funded [ ]. all nhs, both public and private, are subjected to the same na- tional quality reporting requirements, user safety regu- lations, and auditing measures [ ]. this study includes all nhs in sweden providing care to individuals over spangler et al. bmc health services research ( ) : page of years of age in , excluding facilities offering only short-term care. data collection two nationally representative surveys conducted in , both developed and administered by the nbhw, serve as the primary sources of data. the first survey is a user satisfaction survey (brukarundersökningen, or user survey) distributed yearly to all individuals over years of age receiving elder care services including nh care. this survey consists of separate items to be rated on a five-point likert scale, relating to their satisfaction with a variety of aspects of elder care services, as well as their health status. among those living in nhs the sur- vey had a response rate of % in , resulting in a total of , responses [ ]. the second data source is a survey sent directly to all nhs in sweden by the nbhw, which assesses a number of processual and structural measures of quality. this survey (enhetsundersökningen, or unit survey) is com- pleted by administrative staff at each nh, and had a re- sponse rate of % in , resulting in responses [ ]. in addition to quality measures, the unit survey provides data on the type of services provided by the nh (general, dementia and/or assisted living), the num- ber of residents in each home, and whether the nh is operated by a public or private entity. while the nbhw has a long experience of developing and administering surveys, and assessments of loss-to follow-up in the user survey have been performed [ ] the psychometric prop- erties of these surveys have not been published in the publicly available literature . observations in the two nbhw survey datasets for were matched based on the nh name and munici- pality. this involved both an automated matching process, and a subsequent manual review of unmatched records. municipality-level variables were extracted from the national municipality and county council database kolada [ ] and merged into the dataset. variables variables for analysis were aggregated from the two sur- veys based on their conceptual meaning and the results of an exploratory factor analysis which may be found in additional file , p – . the extracted variables are de- tailed below, and a summary of the categorization is available as additional file . dependent variable upon exploratory factor analysis, it was found that ques- tions in the user survey were highly correlated (cron- bach’s alpha = . ), and was a poor candidate for approaches based on extraction of distinct latent vari- ables. as such, we chose to extract a single composite measure of satisfaction from the user survey for use as the dependent variable, consisting of questions – , – , and . to generate a composite measure for use as the dependent variable, the percent of residents at a nursing home responding positively to a given survey question was normalized by subtracting the average per- centage of patients responding positively to that ques- tion in the population, and dividing by the standard deviation of the population, resulting in a standardized z-score. z-scores were then averaged across all included survey items to result in a composite score with equal weights for each question. independent variables the nbhw divided the unit survey into conceptual categories. a factor analysis showed that the individual questions generally loaded well onto the categories pro- posed by the nbhw and it was therefore chosen, with a few exceptions, to retain this categorization as the basis for the independent variables used in the analysis. based on the donabedian model, the independent variables were divided into “structural” and “processual” variables. processual variables the first seven variables related to different processual factors, such as meal-related routines or physical or so- cial activities. questions and a in the unit survey related to the ability of residents to participate in “resident councils” where residents regularly meet to voice concerns in the nh. issues raised during resident councils may for in- stance include the planning of common activities or menus for the coming weeks. these were aggregated and reported as the variable participation in resident councils. questions and in the unit survey concerned the existence of-, and the residents participation in, the cre- ation of “action plans” concerning the care needs and wishes of the resident. these action plans contain infor- mation about how various care activities are to be car- ried out and should be updated every months. the questions were combined into the variable individual- ized action plans. questions and addressed the existence of meal- related routines, and the documentation of meal prefer- ences in the residents’ action plans. such meal routines are to be based on the five aspects meal model (famm) proposed by gustafsson et al. [ ], and should be updated every months. the questions were com- bined into the variable meal-related routines and plans. questions a-c in the survey related to the existence of formal routines for handling resident safety issues such as threats, violence, and addiction. while the nbhw grouped question (routines for cooperation spangler et al. bmc health services research ( ) : page of with relatives) into this category, it did not load well onto a common factor and is conceptually quite distinct, and was therefore excluded. the remaining questions were combined into the variable patient safety routines. questions and a-b in the unit survey related to fa- cilities for-, and availability of, exercise and social activ- ities. we excluded question (whether the nh residents have access to facilities for physical activity), which had a weak-to-moderate factor loading, so as to interpret this variable as a purely process-related measure. the remaining questions were combined into the variable availability of exercise and social activity. questions and related to the existence of routines for planning care in cooperation with other healthcare providers, and whether resident’s involvement was docu- mented. similarly, questions and related to rou- tines for medication reviews and whether resident participation is documented in the medical record. we reported these as the variables care coordination rou- tines and medication review routines, respectively. structural variables the structural variables included indicators of staffing, ownership and size. three factors relating to staffing from the unit survey, including the ratio of nurses per resident (questions and ), non-nurse staff per resi- dent (questions and ), and the portion of staff with an “adequate education” for their position (questions & ) were identified. these are reported as the variables nurses per resident, staff per resident, and staff with ad- equate education respectively, and weekday and weekend staffing levels were weighted at a : ratio to represent average daily staffing levels. while staffing ratios are fairly straightforward to calculate, the definition of what constitutes an “adequate education” is more complex. adequacy is determined by the amount of healthcare- related training completed by non-nurse staff based on a point scale established by the nbhw [ ]. the number of beds available at each nh was re- ported as size of nursing home. the nh’s ownership sta- tus, i.e. whether it was run by a private or a public provider, was reported as the variable private ownership. controls several variables were included in the analysis to control for population health differences between the nhs in- cluded in this study. self-rated health has been found to be an excellent predictor of clinical outcomes [ , ], and we used questions – and in the user satisfac- tion survey, which asked about the residents’ physical and mental well-being, to control for health status. the type of facilities (general, dementia and/or assisted liv- ing) available at the nh was also controlled for. it was further deemed necessary to control for demographic factors for which data was only available at the municipal level. this refers to different demo- graphic, economical, and political conditions which may vary significantly between the municipalities. a set of controls were adapted from previous studies [ , , ] including per capita income levels, popu- lation density, age profiles, political control, and ex- penditures, the details of which may be found in table . data at the municipality level was collected from the kolada database [ ]. statistical analysis as the large number of quality measures made available by the nbhw was unsuited to direct inclusion in a regression-modelling framework, an initial exploratory factor analysis was performed to reduce the dimension- ality of the dataset as described above. data from the user satisfaction survey and the unit survey were aggre- gated at the nh level. we sought to minimize bias in the estimation of the effects of the investigated quality measures by drawing upon the approach to causal mod- elling first described by pearl [ ], using the assumptions of causal directionality described by the donabedian model of healthcare quality [ , ]. the donabedian model asserts that a causal relationship exists between structural and processual aspects of healthcare quality, and we assumed that the satisfaction of nh residents would be confounded by their health status. to control for confounding due to these causal relationships, the ef- fects of processual measures of quality were modeled controlling for resident health and structural measures of quality. we present coefficient estimates for structural measures including controls for other measures of struc- tural quality, though the direction of causality within the selected set of structural measures is in many cases un- clear. in addition to these full models, we present add- itional nested models estimating bivariate associations, and models controlling only for resident health. in this framework, variations in the regression coefficients be- tween the full and nested models allowed for the inter- pretation of the impact of health status and structural factors on the effect of the quality measures. the aggregated variables were first analyzed in a classical ordinary least squares regression framework using the huber-white sandwich estimator to account for heteroscedasticity and clustering as implemented in the rms r package [ ]. hierarchal models includ- ing municipality-level controls with random intercepts for municipalities were implemented using a “partial pooling” approach to account for clustering and con- founding due to municipal-level factors [ ], as im- plemented in the lme r package [ ]. confidence spangler et al. bmc health services research ( ) : page of intervals were generated using basic parametric boot- strap resampling. in this analysis, we report our results in terms of standardized regression coefficients. while this allows for direct comparison of the importance of each inde- pendent variable in predicting resident satisfaction, it makes interpretation in terms of absolute effects cum- bersome. given the low rates of missing data at the unit level, multiple imputation was not deemed to be necessary, and cases with missing values were deleted list-wise in the relevant models. all statistical analyses were performed using r version . . , and a reprodu- cible accounting of our reported findings is included as additional file . a number of sensitivity analyses investigating the impact of various model specifications, potential biases due to loss to follow- up, and assumptions made in the main analysis are also included in additional file . source code and the data necessary to reproduce these findings are available on mendeley data [ ]. results data from both surveys (the user survey and the unit survey) were aggregated at the nh level, resulting in records in the user survey, and records in the unit survey. records could be automatically linked based on municipality and nh names, and an additional records could be matched through man- ual review, resulting in a dataset containing nhs. an analysis of non-matched records may be found in table descriptive statistics of aggregate variables mean sd median iqr missing dependent variable aggregate resident satisfaction . * . * . . processual variables participation in resident councils . * . * . . individualized action plans . * . * . . meal-related routines and plans . * . * − . . patient safety routines . * . * − . . care coordination routines . * . * − . . medication review routines . * . * . . availability of exercise and activities . * . * . . structural variables private ownership of nursing home . . . . size of nursing home . . . . nurses per resident . . . . staff per resident . . . . staff with adequate education . . . . has general care facilities . . . . has dementia care facilities . . . . has assisted living facilities . . . . resident health controls aggregate self-rated health . * . * − . . municipal controls (weighted by # of nursing homes in municipality) population + in nursing home (%) . . . . population + (%) . . . . population per square kilometer . . . average annual cost per resident (sek) , , , , average age of residents in nursing homes . . . . political control (left = − , mixed = , right = ) − . . . . average annual per capita taxable income (sek) , , , , *these variables are mean centered and normalized. the reader may draw conclusions regarding the distribution of the normalized variables by examining the median to determine skew, and iqr to assess for kurtosis (a standard normal distribution has an iqr of . ) spangler et al. bmc health services research ( ) : page of additional file . p – . an analysis of the association between survey response rates and the investigated var- iables was performed. we found a positive association between response rates and resident satisfaction, as well as a negative association between response rates and nursing home size, and an effect indicating that private nursing homes had higher response rates (see dropout analysis in additional file , p ). generally, residents of nhs were quite satisfied; in the survey, % an- swered that they overall were fairly or very satisfied with the care they received. descriptive data descriptive statistics were generated for each of the vari- ables included in the analysis, and are presented in table . we found that the average nh in sweden has space for residents, a resident to staff ratio of roughly . : , a resident to nurse ratio of : , and that % of non- nurse staff had an adequate level of education as defined by the nbhw criteria. % of included nhs were oper- ated by private providers. % of nhs offered general care services, while % offered dementia care services, and only % had assisted living facilities – these sum up to over % as a single nh can offer more than one type of service. with regard to municipality level statistics, we see that about % of swedes are over the age of , % of whom live in nhs, where the average age of resi- dents is . the average annual per-resident cost for the municipality is thousand sek (around thousand eur), while average per capita taxable in- come is thousand sek (table ). regression analysis figure presents the summarized results of each of the models developed to characterize the independent vari- ables created from the unit survey. a presents the re- sults using a classical ols regression framework, while b presents the results of hierarchal mixed-effects models controlling for municipal level effects. in terms of overall predictive value, an ols model in- cluding all covariates achieved an adjusted r of . , while the conditional r value [ ] of the multi-level model containing all predictor variables was . . in the multi-level framework, we found that variation be- tween municipalities accounted for % of the total vari- ation found between nhs. a total of processual and structural variables were extracted from the unit survey for analysis as independent variables. upon analyzing the results, variable groupings were identified post hoc based on similarities with regard to effect sizes and con- ceptual meanings, which are used to simplify the discus- sion of our findings, and are labelled on the right-hand side of fig. . the variables in the first group, labelled individualized care, are all related to the individual care process. they include the variables participation in resident councils, individualized care plans, and meal-related routines and plans. this group had an average effect size of . in our fully controlled models, and while % confidence intervals in the main model consistently excluded zero after adjusting for municipality-level covariates. the sig- nificance of the variables in this group varied upon sen- sitivity analyses however (see additional file , p – ). the next group, labelled safe care, includes the vari- ables patient safety routines, care coordination rou- tines, and medication review routines. they are all related to the existence of formal guidelines dealing with various aspects of care. as seen in fig. , none of these variables displayed significant correlations to resi- dent satisfaction. the final group in the processual category consists of only one variable, availability of exercise and social activity. this variable, labelled activity, displayed the highest degree of correlation with overall resident sat- isfaction among the process variables, with an effect size of . in our fully controlled model, and was ro- bust across a range of sensitivity analyses. turning to the structural variables, another three vari- able groups were identified. we identified no significant effects in the ols model with regard to ownership sta- tus. upon controlling for municipality-level variables, a significant positive correlation with a magnitude of . in the fully controlled model was found, though the sig- nificance of the association was sensitive to variations in model specifications. the size of the nh was by a significant margin the most important predictor of resident satisfaction in this analysis, with the negative coefficient suggesting that smaller nhs are associated with more satisfied residents. a small decrease in the effect of this variable could be noticed upon controlling for municipality level effects, suggesting that larger nhs may be more common in municipalities where residents are on average, less satis- fied with their nh care. the effect of size was robust in our sensitivity analyses. the third group of structural variables included nurses per resident, staff per resident and staff with adequate education, and was labelled staffing. the group as a whole had an average effect size of . among the fully controlled models. with the exception of nurse staffing ratios, % confidence intervals consistently excluded zero in the main models, but the significance of the ef- fect was sensitive to varying model specifications. taken together, the results of the analysis presented in fig. show that the structural measure size of the nh was the most important predictor of resident satisfac- tion, followed by the processual availability of exercise spangler et al. bmc health services research ( ) : page of and social activity variable. the effects of the processual individualized care variables and the structural staffing variables were similar in magnitude, as was the effect of private ownership, upon controlling for municipality- level effects. these effects were also sensitive to alternate model specifications. the processual safe care variables were not found to have any significant association with resident satisfaction. fig. standardized regression coefficients of predictors for composite resident satisfaction. this figure presents standardized regression coefficients for each of the analyzed independent variables. coefficients are presented for models including only the relevant independent variable (bivariate), with controls for only the health status of the patient (health controlled), and with controls for both health status and the structural measures (health and structure controlled) spangler et al. bmc health services research ( ) : page of finally, a comment on the significant effects found among our control variables is in order. in our fully controlled model, self-rated health was found to have a strong positive correlation with satisfaction (stan- dardized regression coefficient of . ) suggesting that healthier residents reported considerably higher levels of satisfaction. among the municipality level controls, average nh resident age had a positive correlation with satisfaction, and average per capita taxable in- come had a negative correlation with satisfaction. interestingly, no significant relationship between the amount spent per resident and satisfaction was identi- fied. full model summaries, along with a table report- ing the data upon which fig. is based may be found in additional file , p – . discussion in this study, we investigated a total of variables representing different aspects of care quality reported in the nbhw unit survey. of these, seven were considered to represent process-related quality, and five to represent structural quality. our main findings were that the size of a nh (a structural measure) had the greatest impact on resident satisfaction, followed by the processual measure availability of exercise and social activities. the processual variables concerning individualized care and the structural staffing and private ownership all had similar, weakly positive, effects on resident satisfaction. the processual safe care variables had no significant effect on resident satisfaction. we found no clear differ- ences in terms of effect sizes between processual and structural variables. below, we discuss these findings in order of the effect size identified in our results. the fact that nh size was the best predictor of resi- dent satisfaction suggests that smaller nhs in sweden had more satisfied residents than their larger counter- parts. a recent literature review surveying studies exam- ining the impact of nh size on quality outcomes showed size to be an important predictor of quality, with smaller homes generally having better quality outcomes [ ]. none of the studies investigated the relationship between size and resident satisfaction, though five inves- tigated similar composite “quality of life” measures. there are however some indications that larger nursing homes may be associated with better clinical outcomes such as lower hospitalization risks [ ] and lower rates of antipsychotic medication use [ ]. nh quality is a multi-faceted concept, and it is not necessarily the case that the determinants of quality will affect all aspects of quality in the same way. as such, while this study does add to the evidence that smaller nhs are associated with the type of “soft” quality which resident satisfaction may be said to represent, the results should not be inter- preted as saying anything regarding “harder” measures including clinical outcomes, the determinants of which may be quite different. while size may be an important predictor of satisfac- tion in and of itself, it is also likely that there are causal mechanisms behind this association which mediate the effect of size. previous research has for instance indi- cated that staff turnover may be lower [ ] and staff continuity higher [ ] at smaller nhs. the findings of this study thus emphasize the importance of identifying the more proximal mechanisms by which smaller nhs generate higher levels of satisfaction. the interpersonal aspects of nursing home care which these measures re- flect are however difficult to measure, and investigating the mechanisms behind these softer dimensions of nurs- ing home care may require a more qualitative approach. the availability of exercise and social activities was found to have the strongest association with resident satisfaction among the processual variables. previous research has found that physical activity-related inter- ventions can improve the subjective health status of nh residents [ ], although other studies have found weaker or even negative effects [ ]. our results sug- gest that, overall, nhs which offer more frequent op- portunities for exercise and social activity have higher levels of resident satisfaction. the effect of activity was not diminished by controlling for resident health or nh structure; rather, the effect increased slightly sug- gesting that the provision of such activities may be even more important at nhs with poorer structural precon- ditions, particularly with regard to facility size. three other variable groups had weaker effects with regards to resident satisfaction: individualized care, pri- vate ownership, and staffing. the individualized care variables included participation in resident councils, the use of individualized care plans and the use of meal rou- tines. we identified no previous research regarding the impact of resident councils or the use of individualized care plans on satisfaction in the literature, though lucas et al., [ ] did identify a positive impact of similar “fam- ily councils”. our findings suggest that these quality im- provement measures may indeed be associated with higher levels of resident satisfaction, although more di- rected studies are necessary to confirm this. there is some evidence that interventions to improve meal- related processes are effective [ , ], and our results are consistent with a positive impact of such improve- ments on resident satisfaction. the structural measures related to staffing had effect sizes similar to those found among the processual indi- vidualized care measures. staffing as a determinant of care quality has been well researched. in a review of articles, castle [ ] found a preponderance of evidence suggesting that increased staffing levels are positively as- sociated with several measures of nh care quality. more spangler et al. bmc health services research ( ) : page of recent studies by castle and anderson [ ], hyer et al. [ ], and shin and hyun [ ] point to similar results. however, none of these studies investigated effects on resident satisfaction. we found that both non-nurse staffing ratios and education levels were associated with resident satisfaction in all models, while nurse to resi- dent ratios were significant upon controlling for municipal-level factors, and effect sizes were reduced upon controlling for other structural factors. our results are thus consistent with a positive relationship between staffing levels and nh care quality. regarding the effect of ownership, the main results suggest a higher level of resident satisfaction among pri- vately operated nhs after controlling for municipal level covariates. that is to say, while there was no overall dif- ference in absolute levels of satisfaction, a difference was identified upon taking into account that public and pri- vate nhs are not evenly distributed across sweden, and that when the effects of this non-uniform distribution was accounted for (in effect comparing nhs within the same county), a difference could be identified. the somewhat counter-intuitive effect could, at least in part, be explained by the tendency of private care providers in sweden to establish themselves in municipalities with higher income levels, where resident expectations may be higher. this supposition is supported by the finding that average per capita income had a significant negative association with resident satisfaction (see additional file , p ). the significance of ownership status was not robust in sensitivity analyses however, and as such con- stitutes quite weak evidence for the superiority of private over public nursing homes with regards to resident satisfaction. while we found no association between measures of safe care and resident satisfaction, it stands to reason that the processes which these measures represent (e.g. the performance of regular medication reviews and the existence of care coordination plans) are not immediately visible to residents, and are thus less likely to influence satisfaction. studies investigating the impact of these measures on clinical outcomes may well find that they do have an effect with regards to quality in that respect. taken together, the findings of this study indicate that nh residents are more satisfied in smaller nhs, and nhs with frequent opportunities for physical and social activity. only weak effects were identified with regards to processual individualized care measures, pri- vate nursing home ownership, and staffing levels. for- mal routines had no effect on the satisfaction of residents. another contribution of the study is the comparison of the effect of structural and processual variables on satisfaction. in contrast to a previous study on swedish nh care [ ], this study did not lend support to any firm conclusions regarding the superior- ity of one type of quality measure over the other. ra- ther, it was demonstrated that both structural variables such as size, staffing and ownership, and processual variables including individualized care and activities play a role in determining resident satisfaction. the dif- ference in results between the two studies could be ex- plained by the fact that the processual and outcome variables in the kajonius and kazemi study were both drawn from the resident survey (which we found upon factor analysis to be highly inter-correlated), while the structural variables they were compared with were drawn from a separate statistical database lacking this overall correlation. it is thus likely that the differential effects identified by kajonius and kazemi are an arte- fact of how the authors chose to operationalize the pro- cessual and structural measures. furthermore, in the study data was aggregated at the municipal level, thereby investigating only differences in resident satis- faction between municipalities, which we found to ac- count for only % of the total variation in satisfaction between nhs. strengths and limitations this study was a secondary analysis of two nationally representative surveys collected for quality improvement purposes. a strength of the study is thus that the results are likely to generalize well to other contexts similar to that of sweden, and the wide scope of these surveys allowed us to investigate and compare a broad range of factors. a limitation of the study was that the validity and reliability of these surveys has not been established in the publicly available literature, although the nhbw has analyzed the impact of loss to follow-up in the user survey [ ], and performs ongoing internal quality assur- ance of the surveys it conducts. another risk involved in the secondary analysis of data is the proliferation of “re- searcher degrees of freedom” arising from the numerous decisions which must be made in transforming and ana- lyzing such data [ ]. to ameliorate these risks, we sought to define our analysis strategy a priori, and pro- vide the resources necessary to fully reproduce our re- sults [ ]. another limitation is that the aggregate data used in this study precludes the interpretation results in terms of individual-level effects, and readers must be careful to not commit the “ecological fallacy” of inter- preting effects operative at the nh level as applying to individuals. among other simplifying statistical assumptions in- cluding those of additivity and linear effects, we assumed that each question in the survey was equally important to residents in generating the composite measure used as the dependent in our analysis. weighting each ques- tion equally would seem to be a reasonable assumption spangler et al. bmc health services research ( ) : page of to make in the absence evidence regarding resident pref- erences, and the main findings regarding nursing home size and availability of activities were robust to a range of sensitivity analyses and alternate survey question weights. it was common for the satisfaction surveys to be completed with the assistance of third parties, which could potentially influence reported outcomes, and while the rate of missing data was too high to include this variable in the formal analysis, a sub group analysis of homes reporting data on this variable may be found in additional file , p – . based on our findings, we do not expect this factor to be a threat to the validity of our results. we also analyzed the associations present within the user survey data between nh level response rates and the quality measurements reported in the study. we identified a positive correlation between re- sponse rates and satisfaction rates, as has been found in previous studies of this phenomenon [ , ]. we also identified effects suggesting that response rates were higher at smaller nursing homes, and at private nursing homes (see additional file , p ). previous studies have suggested that low response rates are likely to result in an over-estimation of satisfaction [ ]. as such, bias resulting from the systematic differences in response rates would likely be in the direction of under- estimating the association of size and private ownership with satisfaction. conclusions of the quality factors investigated, nh size had the most prominent association with satisfaction, followed by the availability of exercise and social activities. processual measures relating to individualized care, such as partici- pation in resident councils and the formulation of indi- vidualized action plans had a weak association with resident satisfaction, as did other structural factors such as staffing ratios and staff education. the results also suggested that privately managed nhs had a slightly higher level of resident satisfaction, though the effect was similarly weak and appeared only after adjusting for municipality-level covariates. the results in this study suggest that both structural and processual quality fac- tors matter in determining resident satisfaction, with nh size and the availability of exercise and activities having the greatest impact. implications for policy and practice while the findings in this study suggest a direct link be- tween offering more activities and a higher rate of satisfac- tion, more research is needed to determine why residents appear more satisfied at smaller homes. it may be that the proximal causes of satisfaction at smaller nhs could be replicated at their larger counterparts, for instance by improving staff continuity and turnover. if so, this could be a cost-effective alternative to building smaller nursing homes. qualitative studies using methods such as inter- views and participant observation may be most appropri- ate to investigate such effects in more depth. another policy implication is that activities for residents should be a priority in nh care, and in cases where nhs care is contracted out, offering physical and social activities should be a requirement. supplementary information supplementary information accompanies this paper at https://doi.org/ . /s - - - . additional file . analysis_notebook. this document provides additional details regarding the factor analysis undertaken to reduce the dimensionality of the data prior to regression analysis, additional details regarding the main analysis, and a number of post-hoc analyses under- taken to evaluate the sensitivity of the findings, and investigate a number of interesting findings suitable for pursuit in further research. additional file . survey_questions. this document details the specific questions from the two nhbw surveys constituting the aggregate variables included as independent variables in the regression analysis reported in this manuscript. abbreviations famm: five aspects meal model; iqr: inter-quartile range; nbhw: national board of health and welfare; nh: nursing home; ols: ordinary least squares regression; sek: swedish krona acknowledgements we gratefully acknowledge financial support from the swedish research council for health working life and welfare (forte). the authors wish to thank the national board of health and welfare for providing the data used in the study, and the residents and nursing home administrators completing the surveys. authors’ contributions ds, uw and pb conceived of and designed the study. ds performed the analysis and drafted parts of the manuscript. yl performed data cleaning, record matching, and drafted parts of the manuscript. all authors provided substantial input and revisions, and approved the final manuscript. funding the study was funded by the swedish research council for health, working life, and welfare (forte), dnr – . the funding body had no role in the design of the study or collection, analysis, and interpretation of data or in writing the manuscript. open access funding provided by uppsala university. availability of data and materials all data used in this study are publicly available. the data and code use to generate these results are available on mendeley data at: https://doi.org/ . /y zhgxym . ethics approval and consent to participate this study was approved by the uppsala regional ethics review board (dnr – ). a waiver of informed consent was granted by the review board. consent for publication not applicable. competing interests the authors declare that they have no competing interests. spangler et al. bmc health services research ( ) : page of https://doi.org/ . /s - - - https://doi.org/ . /s - - - https://doi.org/ . /y zhgxym . https://doi.org/ . /y zhgxym . author details department of public health and caring sciences, uppsala university, box , uppsala, sweden. department of government, uppsala university, box , uppsala, sweden. department of public health and caring sciences, uppsala university, box , uppsala, sweden. department of public health and caring sciences, uppsala university, box , uppsala, sweden. received: march accepted: october references . sanford a, orrell m, tolson d, abbatecola am, arai h, bauer jm, 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- en rikstäckande undersökning av äldres uppfattning om kvaliteten i hemtjänst och äldreboenden . stockholm: nbhw; . p. – . . wicherts jm, veldkamp cls, augusteijn hem, bakker m, van aert rcm, van assen malm. degrees of freedom in planning, running, analyzing, and reporting psychological studies: a checklist to avoid p-hacking. front psychol. ; : . . mazor km, clauser be, field t, yood ra, gurwitz jh. a demonstration of the impact of response bias on the results of patient satisfaction surveys. health serv res. ; ( ): – . . sitzia j, wood n. response rate in patient satisfaction research: an analysis of published studies. int j qual health care. ; ( ): – . publisher’s note springer nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. spangler et al. bmc health services research ( ) : page of https://doi.org/ . /y zhgxym . https://doi.org/ . /y zhgxym . abstract background methods results conclusions background methods setting data collection variables dependent variable independent variables processual variables structural variables controls statistical analysis results descriptive data regression analysis discussion strengths and limitations conclusions implications for policy and practice supplementary information abbreviations acknowledgements authors’ contributions funding availability of data and materials ethics approval and consent to participate consent for publication competing interests author details references publisher’s note durham research online deposited in dro: may version of attached �le: published version peer-review status of attached �le: peer-reviewed citation for published item: harland-lang, l. a. and martin, a. d. and motylinski, p. and thorne, r. s. ( ) 'charm and beauty quark masses in the mmht global pdf analysis.', european physical journal c., ( ). p. . further information on publisher's website: https://doi.org/ . /epjc/s - - - publisher's copyright statement: c© the author(s) open access this article is distributed under the terms of the creative commons attribution . international license (http://creativecommons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. funded by scoap additional information: use policy the full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro�t purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in dro • the full-text is not changed in any way the full-text must not be sold in any format or medium without the formal permission of the copyright holders. please consult the full dro policy for further details. durham university library, stockton road, durham dh ly, united kingdom tel : + ( ) | fax : + ( ) https://dro.dur.ac.uk https://www.dur.ac.uk https://doi.org/ . /epjc/s - - - http://dro.dur.ac.uk/ / https://dro.dur.ac.uk/policies/usepolicy.pdf https://dro.dur.ac.uk eur. phys. j. c ( ) : doi . /epjc/s - - - regular article - theoretical physics charm and beauty quark masses in the mmht global pdf analysis l. a. harland-lang , a. d. martin , p. motylinski , r. s. thorne ,a department of physics and astronomy, university college london, london wc e bt, uk institute for particle physics phenomenology, durham university, durham dh le, uk received: october / accepted: december / published online: january © the author(s) . this article is published with open access at springerlink.com abstract we investigate the variation in the mmht pdfs when we allow the heavy-quark masses mc and mb to vary away from their default values. we make pdf sets avail- able in steps of �mc = . gev and �mb = . gev, and present the variation in the pdfs and in the predictions. we examine the comparison to the hera data on charm and beauty structure functions and note that in each case the heavy-quark data, and the inclusive data, have a slight pref- erence for lower masses than our default values. we provide pdf sets with three and four active quark flavours, as well as the standard value of five flavours. we use the pole mass definition of the quark masses, as in the default mmht analysis, but briefly comment on the ms definition. introduction over the past few years there has been a significant improve- ment both in the precision and in the variety of the data for deep-inelastic and related hard-scattering processes. since the mstw analysis [ ] we have seen the appearance of the hera combined h and zeus data on the total [ ] and also on the charm structure functions [ ], together with a variety of new hadron-collider data sets from the lhc, and in the form of updated tevatron data (for full references see [ ]). additionally, the procedures used in the global pdf analyses of data have been improved, allowing the parton distributions of the proton to be determined with more pre- cision and with more confidence. this allows us to improve predictions for standard model signals and to model stan- dard model backgrounds to possible experimental signals of new physics more accurately. one area that now needs care- ful attention, at the present level of accuracy, is the treatment of the masses of the charm and beauty quarks, mc and mb, in the global analyses. here we extend the recent mmht a e-mail: thorne@hep.ucl.ac.uk global pdf analysis [ ] to study the dependence of the pdfs, and the quality of the comparison to data, under variations of these masses away from their default values of mc = . gev and mb = . gev, as well as the resulting predictions for processes at the lhc. we make available central pdf sets for a variety of masses, namely mc = . – . gev in steps of . gev and mb = . – . gev in steps of . gev. we also make available the standard mmht pdfs, and the sets with varied masses in the three and four flavour number schemes. dependence on the heavy-quark masses . choice of range of heavy-quark masses in the study of heavy-quark masses that accompanied the mstw pdfs [ ] we varied the charm and beauty quark masses, defined in the pole mass scheme, from mc = . to . gev and mb = to . gev. this was a very generous range of masses, and it was not clear that there was a demand for pdfs at the extreme limits. hence, this time we are a little more restrictive, and study the effects of varying mc from . to . gev, in steps of . gev, and of varying mb from . to . gev in steps of . gev. part of the reason for this is that the values are constrained by the comparison to data, though for both charm and beauty the preferred values are at the lower end of the range, as we will show. however, there is also the constraint from other determinations of the quark masses. these are generally quoted in the ms scheme, and in [ ] are given as mc(mc) = ( . ± . ) gev and mb(mb) = ( . ± . ) gev. the transformation to the pole mass definition is not well defined due to the diverging series, i.e. there is a renormalon ambiguity of ∼ . – . gev. the series is less convergent for the charm quark, due to the lower scale in the coupling, but the renormalon ambiguity cancels in difference between the charm and beauty masses. http://crossmark.crossref.org/dialog/?doi= . /epjc/s - - - &domain=pdf mailto:thorne@hep.ucl.ac.uk page of eur. phys. j. c ( ) : indeed, we obtain m pole b −m pole c = . gev with a very small uncertainty [ , ]. using the perturbative expression for the conversion of the beauty mass, and the relationship between the beauty and charm mass, as shown in [ ], we obtain m pole c = . ± . gev and mpoleb = . ± . gev. ( ) this disfavours mc ≤ . – . gev and mb ≤ . – . gev. as the fit quality prefers values in this region, or lower, we allow some values a little lower than this. in the upper direc- tion the fit quality clearly deteriorates, so our upper values are not far beyond the central values quoted above. there is some indication from pdf fits for a slightly lower mpole than that suggested by the use of the perturbative series out to the order at which it starts to show lack of convergence. we now consider the variation with mc and mb in more detail. . dependence on mc we repeat the global analysis in [ ] for values of mc = . – . gev in steps of . gev. as in [ ] we use the “optimal” version [ ] of the tr’ general-mass variable-flavour-number scheme gm-vfns [ ]. this is smoother near the transi- tion point, which we define to be at q = μ = m c , than the original version, so has a slight tendency to prefer lower masses—the older version growing a little more quickly at low scales, which could be countered by increasing the mass. we also assume all heavy flavour is generated by evolution from the gluon and light quarks, i.e. there is no intrinsic heavy flavour. we perform the analysis with αs(m z ) left as a free parameter in the fit at both nlo and nnlo, but also use our fixed default values of the coupling of αs(m z ) = . and . at nlo and αs(m z ) = . at nnlo. unlike the mstw study [ ] we will concentrate on the results and pdfs with fixed coupling, as the standard mmht pdfs were made available at these values. we present results in terms of the χ for the total set of data in the global fit and for just the data on the reduced cross section, σ̃ cc̄, for open charm production at hera [ ]. this is shown at nlo with αs(m z ) = . in fig. . the variation in the quality of the fit to the hera combined charm cross section data is relatively slight, less than the variation in the fit to the separate h and zeus data used in [ ]. this is presum- ably due to the use of the full information now available on correlated systematics, which allows movement of the data relative to the theory with only a moderate penalty in χ . the lower variation is also likely due in part to the improved flavour scheme. despite the fairly small variation in χ the charm data clearly prefer a value close to mc = . gev, near our default value of mc = . gev. however, there is more variation in the fit quality to the global data set, with a clear preference for values close to mc = . gev. the dete- rioration is clearly such as to make values of mc > . gev strongly disfavoured. the main constraint comes from the inclusive hera cross section data, but there is also some preference for a low value of the mass from nmc structure function data, where the data for x ∼ . and q ∼ gev is sensitive to the turn-on of the charm contribution to the structure function. overall, there is some element of tension between the preferred value for the global fit and the fit to charm data. we do not attempt to make a rigorous determi- nation of the best value of the mass or its uncertainty, as provided in [ ] for example, as we believe there are more precise and better controlled methods for this. however, a rough indication of the uncertainty could be obtained from the χ profiles by treating mc in the same manner as the stan- dard pdf eigenvectors and applying the dynamic tolerance procedure. in this case the appropriate tolerance, obtained mc [gev] χ σ̃cc ( pts), nlo, αs(m z) = . . . . . . . . . . . mc [gev] χ global ( pts), nlo, αs(m z) = . . . . . . . . . . . fig. the quality of the fit versus the quark mass mc at nlo with αs(m z ) = . for (left) the reduced cross section for charm production σ̃ cc̄ for the combined h and zeus data and (right) the full global fit eur. phys. j. c ( ) : page of mc [gev] χ σ̃cc ( pts), nlo, αs(m z) = . . . . . . . . . . . mc [gev] χ global ( pts), nlo, αs(m z) = . . . . . . . . . . . fig. the quality of the fit versus the quark mass mc at nlo with αs(m z ) = . for (left) the reduced cross section for charm production σ̃ cc̄ for the combined h and zeus data and (right) the full global fit table the quality of the fit versus the quark mass mc at nlo with αs(m z ) left as a free parameter mc (gev) χ global χ σ̃ cc̄ αs(m z ) pts pts . . . . . . . . . . . . . . . . . . by assuming the charm cross section data is the dominant constraint, would be of the order t = √ �χ ≈ . . the analogous results for αs(m z ) = . and αs(m z ) left free are shown in fig. and table , respectively, where in the latter case the corresponding αs(m z ) values are shown as well. for αs(m z ) = . the picture is much the same as for αs(m z ) = . except that the fit to charm data is marginally better, while the global fit is a little worse, though more-so for higher masses. the results with free αs(m z ) are consistent with this, with the preferred value of αs(m z ) falling slightly with lower values of mc. however, the values of mc preferred by charm data and the full data sets are much as discussed in [ ], for a % confidence level uncertainty we insist the fit quality to a given data set deteriorates by no more than the width of the χ distribution for n points, roughly √ n/ multiplied by the χ per point for the best fit. for the charm cross section data this is ≈√ / × . . the same as for fixed coupling—the values of the χ just being a little lower in general. the results of the same analysis at nnlo are shown for αs(m z ) = . and αs(m z ) left free in fig. and table , respectively, where again in the latter case the corresponding αs(m z ) values are shown. broadly speaking, the results are similar to those at nlo, but with lower values of mc preferred and where the χ variation is greater for the inclusive data than for the charm cross section data. however, in this case there is essentially no tension at all between the inclusive and charm data, with both χ values minimising very near to mc = . gev—this lower preferred value for the charm data meaning that the fit quality at mc = . gev has deteriorated more than at nlo. the picture is exactly the same for fixed and free strong coupling, with the values of χ simply being a little lower when αs(m z ) is left free, since the best fit value of the coupling is a little below . , particularly for low mc. . dependence on mb we repeat essentially the same procedure for varying val- ues of mb in the range . – . gev in steps of . gev. however, this time there were no data on the beauty contri- bution to the cross section included in the standard global fit [ ]. in the previous heavy-quark analysis [ ] we compared to beauty cross section data from h [ ]. this placed a weak constraint on the value of mb but had negligible constraint on the pdfs for fixed mb. hence, we did not include these data in the updated global fit [ ]. there are now also data of comparable precision from zeus [ ], and we will include both these data sets in future global fits. in this article we study the quality of the comparison to these data to predic- page of eur. phys. j. c ( ) : mc [gev] χ σ̃cc ( pts), nnlo, αs(m z) = . . . . . . . . . . . mc [gev] χ global ( pts), nnlo, αs(m z) = . . . . . . . . . . . fig. the quality of the fit versus the quark mass mc at nnlo with αs(m z ) = . for (left) the reduced cross section for charm production σ̃ cc̄ for the combined h and zeus data and (right) the full global fit table the quality of the fit versus the quark mass mc at nnlo with αs(m z ) left free mc (gev) χ global χ σ̃ cc̄ αs(m z ) pts pts . . . . . . . . . . . . . . . . . . tions obtained using the mmht pdfs with different values of mb. the data themselves are not included in the fit, i.e. we use predictions from the pdfs, as they still provide negligible direct constraint. the results for the nlo pdfs with αs(m z ) = . and . are shown in figs. and , respectively. the picture for the data in the global fit (not including the σ̃ bb̄ data) is slightly different in the two cases: for αs(m z ) = . there is a fairly weak tendency to prefer lower values of mb, similar to the results in [ ], but for αs(m z ) = . the global fit prefers a value of between . and . gev. for the predictions for the beauty cross section data, however, the picture is similar in the two cases, and low values of mb ∼ . – . gev are preferred. the results for the nnlo fit with αs(m z ) = . are shown in fig. . as can be seen the global fit is fairly weakly dependent on mb, though more than for αs(m z ) = . at nlo, and prefers a value lower than mb = . gev. as in the nlo case the χ for the prediction for σ̃ bb̄ is better for lower values of mb. the slightly larger variations in the quality of the global fit with varying mb compared to [ ] is perhaps due to the greater precision of the inclusive hera cross section data used in this analysis, and to the fact that the cms double-differential drell–yan data [ ] has some sensitivity to the value of mb due to the induced variation in sea quark flavour composition for low scales. the previous analysis preferred a value of mb ∼ . gev for the com- parison to the h beauty data. however, the definition of the general-mass variable-number scheme has improved since this previous analysis, being smoother near to the transition point q = m b, and including an improvement to the approx- imation for the o(α s) contribution at low q at nnlo, so some changes are not surprising. another important differ- ence is in the treatment of the correlated experimental errors, which we now take as being multiplicative. the result within exactly the same framework, but with the experimental errors on the hera beauty data instead treated as additive is also shown in fig. and a higher value of mb ∼ . gev is clearly preferred. similar results are seen in the nlo fits. in fig. the comparison to the (unshifted) hera beauty data for different values of mb at nnlo is shown. at low q and for zeus data in particular, the curves for lower mb are clearly a better fit to unshifted data. how- ever, the low-m b predictions do significantly overshoot some of the unshifted data points. these predictions will work better with the multiplicative definition of uncertainties as the size of the correlated uncertainties then scales with the prediction, not the data point (as would be the case in the additive definition), or equivalently, if data are nor- malised up to match theory, then so is the uncorrelated uncertainty. eur. phys. j. c ( ) : page of mb [gev] χ σ̃bb ( pts), nlo, αs(m z) = . . . . . . mb [gev] χ global ( pts), nlo, αs(m z) = . . . . . . fig. the quality of the fit versus the quark mass mb at nlo with αs(m z ) = . for (left) the reduced cross section for beauty production σ̃ bb̄ for the h and zeus data and (right) the global fit, not including the beauty data mb [gev] χ σ̃bb ( pts), nlo, αs(m z) = . . . . . . mb [gev] χ global ( pts), nlo, αs(m z) = . . . . . . fig. the quality of the fit versus the quark mass mb at nlo with αs(m z ) = . for (left) the reduced cross section for beauty production σ̃ bb̄ for the h and zeus data and (right) the global fit, not including the beauty data . changes in the pdfs we show how the nlo pdfs for mc = . and . gev compare to the central pdfs in figs. and . results are very similar at nnlo, though more complicated to inter- pret for the charm distribution at low q due to the non-zero transition matrix element at q = m c in this case. we see at q = gev (that is, close to the transition point q = m c ) that the change in the gluon is well within its uncertainty band, though there is a slight increase at smaller x with higher mc (and vice versa) such that extra gluon quickens the evo- lution of the structure function which is suppressed by larger mass. similarly the light quark singlet distribution increases slightly near the transition point for larger mc to make up for the smaller charm contribution to structure functions, and this is maintained, helped by the increased gluon, at larger scales. in both cases, however, the changes are within uncertainties for these moderate variations in mc. the charm distribution increases at low q for decreasing mc, and vice versa, sim- ply due to increased evolution length ln(q /m c). as men- tioned before we have identified the transition point at which heavy flavour evolution begins with the quark mass. this has the advantage that the boundary condition for evolution is zero up to nlo (with our further assumption that there is no intrinsic charm), though there is a finite o(α s) boundary condition at nnlo in the gm-vfns, available in [ ]. in principle the results on the charm distribution at relatively low scales, such as that in fig. are sensitive to these defini- page of eur. phys. j. c ( ) : mb [gev] χ σ̃bb ( pts), nnlo, αs(m z) = . . . . . . mb [gev] χ global ( pts), nnlo, αs(m z) = . . . . . . mb [gev] χ σ̃bb ( pts), nnlo, αs(m z) = . , additive errorrs . . . . . fig. the quality of the fit versus the quark mass mb at nnlo with αs(m z ) = . for (left) the reduced cross section for beauty pro- duction σ̃ bb̄ for the h and zeus data and (right) the global fit, not including the beauty data. recall that in the mmht analysis the exper- imental errors are treated multiplicatively. the lower plot shows the χ profile if the errors in the hera beauty data were to be treated additively tions at finite order, though as the order in qcd increases the correction for changes due to different choices of the tran- sition point arising from the corresponding changes in the boundary conditions become smaller and smaller, ambigu- ities always being of higher order than the calculation. at scales typical of most of lhc physics, however, the rela- tive change in evolution length for the charm distribution is much reduced, as are the residual effects of choices relating to the choice of the transition point and intrinsic charm. at these scales the change in the charm distribution is of the same general size as the pdf uncertainty for fixed mc, as seen in fig. . we also note that the charm structure func- tion at these high scales is reasonably well represented by the charm distribution, while at low scales, certainty including q = gev , this is not true. indeed at nnlo the boundary condition for the charm distribution is negative at very low x if the transition point is m c , but this is more than compensated for by the gluon and light quark initiated cross section. as noted in [ ], use of a zero mass scheme becomes unfeasible at nnlo. the dependence on the heavy-quark cross section at low scales relative to the mass is much better gauged from fig. . the relative changes in the gluon and light quarks for variations in mb are significantly reduced due to the much smaller impact of the beauty contribution to the structure functions from the charge-squared weighting, as can be seen in figs. and , where we show nlo pdfs for mb = . and . gev. at q = gev ∼ m b the relative change eur. phys. j. c ( ) : page of zeus h mb = . gev mb = . gev mb = . gev mb = . gev mb = . gev x σ̃bb, q = gev . . . . . . . . x σ̃bb, q = . gev . . . . . . . . . . x σ̃bb, q = gev . . . . . . . . x σ̃bb, q = gev . . . . . . . x σ̃bb, q = gev . . . . . . . . x σ̃bb, q = gev . . . . . . . . . x σ̃bb, q = gev . . . . . . . . . x σ̃bb, q = gev . . . . . . . x σ̃bb, q = gev . . . . . . . . . . x σ̃bb, q = gev . . . . . . . . . x σ̃bb, q = gev . . . . . . . . . x σ̃bb, q = gev . . . . . . fig. the (unshifted) hera σ̃ (bb̄) data versus x at different values of q , namely q = , . , . . . , gev ; the h [ ] and zeus [ ] data are shown as solid circular and clear trian- gular points, respectively. the curves are the nnlo predictions for five different values of mb, namely, in descending order, mb = . , . , . , , . gev in the beauty distribution for a ∼ % change in the mass is similar to that for the same type of variation for mc. how- ever, the extent to which this remains at q = gev is much greater than the charm case due to the smaller evolution length. effect on benchmark cross sections in this section we show the variation with mc and mb for cross sections at the tevatron, and for and tev at the lhc. variations for and tev will be very similar to page of eur. phys. j. c ( ) : − − . . . . gluon (nlo), percentage difference at q = gev x mmht mc = . gev mc = . gev − − . . . . light quarks (nlo), percentage difference at q = gev x mmht mc = . gev mc = . gev − − − . . . . charm quark (nlo), percentage difference at q = gev x mmht mc = . gev mc = . gev fig. the mc dependence of the gluon, light-quark singlet and charm distributions at nlo for q = gev , compared to the standard mmht distributions with mc = . gev and mb = . gev those at and tev, respectively. we calculate the cross sections for w and z boson, higgs boson via gluon–gluon fusion and top-quark pair production. to calculate the cross section we use the same procedure as was used in [ , ]. that is, for w, z and higgs production we use the code provided by w.j. stirling, based on the calculation in [ – ], and for top pair production we use the procedure and code of [ ]. here our primary aim is not to present definitive predictions or to compare in detail to other pdf sets, as both these results are frequently provided in the literature with very specific choices of codes, scales and parameters which may differ from those used here. rather, our main objective is to illustrate the relative influence of varying mc and mb for these benchmark processes. we show the predictions for the default mmht pdfs, with pdf uncertainties, and the relative changes due to changing mc from . to . gev, and mb from . to . gev, i.e. changing the default values by approximately % in each case. the dependence of the benchmark pre- dictions on the value of mc in tables , and reflects the behaviour of the gluon with √ s. the changes in cross sec- tion generally scale linearly in variation of masses away from the default values to a good approximation, although for mb, where the cross section sensitivity to the mass choice is often small, this is less true, and in some cases the cross section is even found to decrease or increase in both directions away from the best fit mass. we begin with the predictions for the w and z production cross sections. the results at nnlo are shown in table . the pdf uncertainties on the cross sections are % at the teva- tron and slightly smaller at the lhc—the lower beam energy at the tevatron meaning the cross sections have more contri- bution from higher x where the pdf uncertainties increase. the mc variation is at most about . % at the tevatron and is . – % at the lhc, being larger at tev. the results at nlo are very similar. in table we show the analogous results for the top-quark pair production cross section. at the tevatron the pdfs are probed in the region x ≈ . / . ≈ . , and the main pro- duction is from the qq̄ channel. at the lhc the dominant pro- duction at higher energies (and with a proton–proton rather than proton–antiproton collider) is gluon–gluon fusion, with the central x value probed being x ≈ . / ≈ . at tev, and x ≈ . / ≈ . at tev. the pdf uncertainties on the cross sections are nearly % at the tevatron, similar for tev at the lhc, but a little smaller at tev as there is less sensitivity to the high-x gluon. the mc variation are slightly less than % at the tevatron and for tev at the eur. phys. j. c ( ) : page of − . . . . gluon (nlo), percentage difference at q = gev x mmht mc = . gev mc = . gev − . . . . light quarks (nlo), percentage difference at q = gev x mmht mc = . gev mc = . gev − − . . . . charm quark (nlo), percentage difference at q = gev x mmht mc = . gev mc = . gev fig. the mc dependence of the gluon, light-quark singlet and charm distributions at nlo for q = gev , compared to the standard mmht distributions with mc = . gev and mb = . gev lhc, but rather lower at tev since the x probed is near the fixed point for the gluon (see fig. ). in table we show the uncertainties in the rate of higgs boson production from gluon–gluon fusion. at the tevatron the dominant x range probed, i.e. x ≈ . / . ≈ . , corresponds to a region where the gluon distribution falls as mc increases and at the lhc where x ≈ . – . at central rapidity the gluon increases as mc increases, though at tev we are only just below the fixed point. at the tevatron the resultant uncertainty is ∼ . %. at the lhc at tev it is in the opposite direction but only ∼ . %, whereas at tev it has increased to near . %. as in [ ] we recommend that in order to estimate the total uncertainty due to pdfs and the quark masses it is best to add the variation due to the variation in quark mass in quadrature with the pdf uncertainty, or the pdf+αs uncertainty, if the αs uncertainty is also used. pdfs in three- and four-flavour-number schemes in our default studies we work in a general-mass variable- flavour-number scheme (gm-vfns) with a maximum of five active flavours. this means that we start at our input scale of q = gev with three active light flavours. at the transition point m c the charm quark starts evolution and then at m b the beauty quark also starts evolution. the evo- lution is in terms of massless splitting functions, and at high q the contribution from charm and bottom quarks lose all mass dependence other than that in the boundary conditions at the chosen transition point. the explicit mass dependence is included at lower scales, but falls away like inverse powers as q /m c,b → ∞. we do not currently ever consider the top quark as a parton. we could alternatively keep the information about the heavy quarks only in the coefficient functions, i.e. the heavy quarks would only be generated in the final state. this is called a fixed-flavour-number scheme (ffns). one example would be where neither charm and beauty exist as partons. this would be a three-flavour ffns. an alternative would be to turn on charm evolution but never allow beauty to be treated as a parton. this is often called a four-flavour ffns. we will use this notation, but strictly speaking it is a gm- vfns with a maximum of four active flavours. one might produce the partons for the three- and four- flavour ffns by performing global fits in these schemes. page of eur. phys. j. c ( ) : − . . . . gluon (nlo), percentage difference at q = gev x mmht mb = . gev mb = . gev − . . . . light quarks (nlo), percentage difference at q = gev x mmht mb = . gev mb = . gev − − − . . . . bottom quark (nlo), percentage difference at q = gev x mmht mb = . gev mb = . gev fig. the mb dependence of the gluon, light-quark singlet and charm distributions at nlo for q = gev , compared to the standard mmht distributions with mc = . gev and mb = . gev however, it was argued in [ ] that the fit to structure func- tion data is not optimal in these schemes. indeed, evidence for this has been provided in [ , , ]. moreover, much of the data (for example, on inclusive jets and w, z production at hadron colliders) is not known to nnlo in these schemes, and is very largely at scales where mc,b are relatively very small. so it is clear that the gm-vfns are more appropri- ate. hence, in [ ] it was decided to make available pdfs in the three- and four-flavour schemes simply by using the input pdfs obtained in the gm-vfns, but with evolution of the beauty quark, or both the beauty and the charm quark, turned off. this procedure was continued in [ ] and is the common choice for pdf groups who fit using a gm-vfns but make pdfs available with a maximum of three or four active flavours. hence, here, we continue to make this choice for the mmht pdfs. we make pdfs available with a maximum of three or four active flavours for the nlo central pdfs and their uncertainty eigenvectors for both the standard choices of α n f,max= s (m z ) of . and . , and for the nnlo central pdf and the uncertainty eigenvectors for the standard choice of α n f,max= s (m z ) of . . we also provide pdf sets with αs(m z ) displaced by . from these default values, so as to assist with the calculation of αs uncertainties in the different flavour schemes. finally, we make available pdf sets with different values of mc and mb in the different fixed-flavour schemes. by default, when the charm or beauty quark evolution is turned off, we also turn off the contribution of the same quark to the running coupling. this is because most calcu- lations use this convention when these quarks are entirely final state particles. this results in the coupling running more quickly. so if the coupling at q is chosen so that α n f,max= s (m z ) ≈ . , then we find that α n f,max= s (m z ) ≈ . and α n f,max= s (m z ) ≈ . . there are sometimes cases where a set of pdfs with no beauty quark but with five-flavour running coupling is desired, e.g. [ ]. after the publication of [ ], pdf sets with this definition were made available. here we make available pdfs for the central sets together with their eigenvectors with a maximum of four active flavours, but the beauty quark included in the running of the coupling. this type of pdf has also been considered very recently in [ ]. the variation of the pdfs defined with a maximum num- ber of three and four flavours, compared to our default of five flavours, is shown at q = gev in fig. for nnlo eur. phys. j. c ( ) : page of − . . . . gluon (nlo), percentage difference at q = gev x mmht mb = . gev mb = . gev − . . . . light quarks (nlo), percentage difference at q = gev x mmht mb = . gev mb = . gev − . . . . bottom quark (nlo), percentage difference at q = gev x mmht mb = . gev mb = . gev fig. the mb dependence of the gluon, light-quark singlet and charm distributions at nlo for q = gev , compared to the standard mmht distributions with mc = . gev and mb = . gev table predictions for w ± and z cross sections (in nb), including leptonic branching, obtained with the nnlo mmht parton sets. the pdf uncertainties and mc and mb variations are also shown, where the mc variation corresponds to ± . gev and the mb variation cor- responds to ± . gev, i.e. about % in each case σ pdf unc. mc var. mb var. w tevatron ( . tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) − . − . ( − . % − . % ) z tevatron ( . tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) − . − . ( − . % − . % ) w + lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) + . − . ( + . % − . % ) w − lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) + . − . ( + . % − . % ) z lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) − . − . ( − . % − . % ) w + lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) + . − . ( + . % − . % ) w − lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) + . − . ( + . % − . % ) z lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) − . − . ( − . % − . % ) pdfs. the general form of the differences are discussed in detail in section of [ ] and are primarily due to two effects. for fewer active quarks there is less gluon branching, so the gluon is larger if the flavour number is smaller. also, as q increases the coupling gets smaller for fewer active quarks, so evolution is generally slower, which means par- tons decrease less quickly for large x and grow less quickly at small x. the latter effect dominates for quark evolution, while for the gluon the two effects compete at small x. for the case where the maximum number of flavours is , but page of eur. phys. j. c ( ) : table predictions for tt cross sections (in nb), obtained with the nnlo mmht parton sets. the pdf uncertainties and mc and mb variations are also shown, where the mc variation corresponds to ± . gev and the mb variation corresponds to ± . gev σ pdf unc. mc var. mb var. tt tevatron ( . tev) . + . − . ( + . % − . % ) − . + . ( − . % + . % ) + . + . ( + . % + . % ) tt lhc ( tev) + . − . ( + . % − . % ) − . + . ( − . % + . % ) + . − . ( + . % − . % ) tt lhc ( tev) + − ( + . % − . % ) − . + . ( − . % + . % ) + . − . ( − . % + . % ) table predictions for the higgs boson cross sections (in nb), obtained with the nnlo mmht parton sets. the pdf uncertainties and mc and mb variations are also shown, where the mc variation corresponds to ± . gev and the mb variation corresponds to ± . gev σ pdf unc. mc var. mb var. higgs tevatron ( . tev) . + . − . ( + . % − . % ) − . + . ( − . % + . % ) + . − . ( + . % − . % ) higgs lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) + . − . ( + . % − . % ) higgs lhc ( tev) . + . − . ( + . % − . % ) + . − . ( + . % − . % ) + . − . ( + . % − . % ) . . . . . . . . f (x, q )/f (x, q ), q = gev x gluon up down strange charm anti–up anti–down . . . . . . . . f (x, q )/f (x, q ), q = gev x gluon up down strange charm anti–up anti–down . . . . . . . . f ,αs( )(x, q )/f (x, q ), q = gev x gluon up down strange charm anti–up anti–down fig. the ratio of the different fixed-flavour pdfs to the standard five flavour pdfs at nnlo and at q = gev . the three and four flavour schemes are show in the top left and right plots, while the four flavour scheme with five flavours in the running of αs is shown in the bottom plot eur. phys. j. c ( ) : page of the coupling has five-flavour evolution, the overwhelming effect is that the gluon is larger—effectively replacing the missing beauty quarks in the momentum sum rule. however, the increase in the gluon is maximal at small x, where the increased coupling compared to the case where we use the four-flavour coupling leading to increased loss of gluons at high x from evolution. renormalisation schemes at present most pdf fitting groups, including the most recent updates [ , – ], use the pole mass definition for the heavy quarks. hence, we have remained with this definition in our investigation of quark mass dependence in this article. the analyses in [ , ] use the ms definition, following the developments in [ ]. the latter analyses perform their fits in the fixed-flavour-number scheme (ffns), while all the others groups use a general-mass variable-flavour-number scheme. there is no fundamental obstacle to switching between the two renormalisation schemes using either approach. the mass dependence in a gm-vfns appears in entirety from the ffns coefficient functions and in the transition matrix elements which set the boundary conditions for the (mass- less) evolution of the charm and beauty quarks. these are used along with the ffns coefficient functions to define the gm-vfns coefficient functions which tend to the massless versions as m c,b/q → . under a change in the definition of the quark mass mpole = m(μr)( + αs(μ r)d (μ r) + · · · ) ( ) the coefficient functions and transition matrix elements can be transformed from one mass scheme to the other straight- forwardly, as illustrated in eq. ( ) of [ ], and the mass in gm-vfns defined in the ms renormalisation scheme. however, there is more sensitivity to the definition of the mass in a ffns at given order than in a gm-vfns. at lo there is no mass scheme dependence in the same way that there is no renormalisation scheme dependence of any sort. at nlo in the ffns the variation of the lo o(αs) coeffi- cient function under the change in eq. ( ) leads to a change in the nlo o(αs) coefficient function. some nlo gm-vfns definitions (e.g. the sacot(χ ) [ ] and the fonll-a [ ]) only use the ffns coefficient functions at o(αs). the tran- sition matrix element for heavy-quark evolution in an nlo gm-vfns is also defined at o(αs) (and indeed is zero with the standard choice μf = mc,b), so neither depend on the mass definition, and the nlo gm-vfns is independent of the mass scheme [ ]. some nlo gm-vfns definitions do use the o(α s) ffns coefficient functions. hence, these will contain some note that d (μ r) = / π if μr = m. dependence on the mass scheme. however, in the original tr [ ] and then the tr’ [ ] schemes this contribution is frozen at q = m c,b, so becomes relatively very small at high q . in the “optimal” tr’ scheme [ ], and in the fonll-b, the dependence falls away like m c,b/q (in the former case the whole o(α s) coefficient function is weighted by m c,b/q , while in the fonll-b scheme the subtraction means that only the massless limit of the o(α s) coefficient function remains as m c,b/q → ). hence, the dependence on the mass scheme is more limited than in the ffns at nlo, and is particularly small. indeed, in all but the original tr and tr’ schemes, there is no dependence at high q . at nnlo the mass scheme dependence in the ffns enters in the o(α s) and o(α s) coefficient functions. in a gm- vfns it now enters in the o(α s) coefficient functions at low scales, and in boundary conditions for evolution, which gives effects which persist to all scales. if the gm-vfns uses the o(α s) coefficient functions these will also give mass scheme dependent effects at low q . however, the expressions for the o(α s) coefficient functions are themselves still approx- imations [ ]. hence, at present it does not seem too important whether the pole mass or ms renormalisation scheme is used in a gm-vfns (indeed in [ ] the pole mass scheme is used, but the ms values for the masses are taken). nevertheless, in the future it is probably ideal to settle on the ms mass, since the value of this is quite precisely determined in many experiments, which is not true of the pole mass. at the same time it will also be desirable for different pdf groups to agree on a common value of mc and mb (there is no agreement at present). conclusions the main purpose of this article is to present and make available pdf sets in the framework used to produce the mmht pdfs, but with differing values of the charm and beauty quark mass. we do not make a determination of the optimum values of these masses, but we do investigate and note the effect the mass variation has on the quality of the fits to the data, concentrating on the hera cross section data with charm or beauty in the final state. we note that for both the charm and beauty quarks a lower mass than our default values of mc = . gev and mb = . gev is pre- ferred, although these are roughly the values of pole masses one would expect from conversion from the values measured in the ms scheme. this suggests that in the future it may be better to use the ms definition, though this is currently not the practice in global fits using a gm-vfns—perhaps because, as we discuss, the mass scheme dependence has less effect in these schemes than for the ffns. we also make pdfs avail- page of eur. phys. j. c ( ) : able with a maximum of three or four active quark flavours. the pdf sets obtained for different quark masses and for different active quark flavours can be found at [ ] and will be available from the lhapdf library [ ]. we investigate the variation of the pdfs and the predicted cross sections for standard processes at the lhc (and teva- tron) corresponding to these variations in heavy-quark mass. for reasonable variations of mc the effects are small, but not insignificant, compared to pdf uncertainties. for vari- ations in mb the effect is smaller, and largely insignificant, except for the beauty distribution itself, which can vary more than its uncertainty at a fixed value of mb; see, in particu- lar fig. . hence, currently the uncertainties on pdfs due to quark masses are not hugely important, but need to be improved in the future for very high precision predictions at hadron colliders. acknowledgments we particularly thank w. j. stirling and g. watt for numerous discussions on pdfs and for previous work without which this study would not be possible. we would like to thank mandy cooper- sarkar, albert de roeck, stefano forte, joey huston, pavel nadolsky and juan rojo for various discussions on the relation between pdfs and quark masses. we would like to thank a. geiser, a. gizhko and k. wichmann for help regarding the treatment of uncertainties for zeus beauty cross sections. this work is supported partly by the london cen- tre for terauniverse studies (lcts), using funding from the european research council via the advanced investigator grant . rst would also like to thank the ippp, durham, for the award of a research associateship held while most of this work was performed. we thank the science and technology facilities council (stfc) for support via grant awards st/j / and st/l / . open access this article is distributed under the terms of the creative commons attribution . international license (http://creativecomm ons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. funded by scoap . references . a.d. martin, w.j. stirling, r.s. thorne, g. watt, eur. phys. j. c , ( ). arxiv: . . h and zeus collaboration, f. aaron et al., jhep , ( ). arxiv: . . h collaboration, zeus collaboration, h. abramowicz et al., eur. phys. j. c , ( ). arxiv: . . l. harland-lang, a. martin, p. motylinski, r. thorne, eur. phys. j. c , ( ). arxiv: . . a. martin, w. stirling, r. thorne, g. watt, eur. phys. j. c , ( ). arxiv: . . particle data group, k. olive et al., chin. phys. c , ( ) . c.w. bauer, z. ligeti, m. luke, a.v. manohar, m. trott, phys. rev. d , ( ). arxiv:hep-ph/ . a.h. hoang, a.v. manohar, phys. lett. b , ( ). arxiv:hep-ph/ . r.s. thorne, phys. rev. d , ( ). arxiv: . . r.s. thorne, phys. rev. d , ( ). arxiv:hep-ph/ . s. alekhin, j. blümlein, k. daum, k. lipka, s. moch, phys. lett. b , ( ). arxiv: . . h , f.d. aaron et al., eur. phys. j. c , ( ). arxiv: . . zeus, h. abramowicz et al., jhep , ( ). arxiv: . . cms collaboration, s. chatrchyan et al., jhep , ( ). arxiv: . . m. buza, y. matiounine, j. smith, w.l. van neerven, eur. phys. j. c , ( ). arxiv:hep-ph/ . l.a. harland-lang, a.d. martin, p. motylinski, r. s. thorne, eur. phys. j. c , ( ). doi: . /epjc/s - - - . r. hamberg, w. van neerven, t. matsuura, nucl. phys. b , ( ) . r.v. harlander, w.b. kilgore, phys. rev. lett. , ( ). arxiv:hep-ph/ . a. djouadi, m. spira, p. zerwas, phys. lett. b , ( ) . m. czakon, p. fiedler, a. mitov, phys. rev. lett. , ( ). arxiv: . . r.s. thorne, w.k. tung, in pqcd formulations with heavy quark masses and global analysis, proceedings, workshop: hera and the lhc workshop series on the implications of hera for lhc physics ( ). arxiv: . . r. thorne, eur. phys. j. c , ( ). arxiv: . . the nnpdf collaboration, r.d. ball et al., phys. lett. b , ( ). arxiv: . . a.d. martin, w.j. stirling, r.s. thorne, phys. lett. b , ( ). arxiv:hep-ph/ . f. cascioli, p. maierhöfer, n. moretti, s. pozzorini, f. siegert, phys. lett. b , ( ). arxiv: . . v. bertone, s. carrazza, j. rojo, in doped parton distributions, th rencontres de blois on particle physics and cosmology blois, france ( ). arxiv: . . the nnpdf collaboration, r.d. ball et al. 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[aip conf. proc. , ( )] . r.s. thorne, r.g. roberts, phys. rev. d , ( ). arxiv:hep-ph/ . h. kawamura, n.a. lo presti, s. moch, a. vogt, nucl. phys. b , ( ). arxiv: . . http://www.hep.ucl.ac.uk/mmht/. accessed jan . http://lhapdf.hepforge.org. accessed jan http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /epjc/s - - - http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://www.hep.ucl.ac.uk/mmht/ http://lhapdf.hepforge.org suicide notes from beautiful girls by lynn weingarten (review) suicide notes from beautiful girls by lynn weingarten (review) kate quealy-gainer bulletin of the center for children's books, volume , number , september , p. (review) published by johns hopkins university press doi: for additional information about this article [ access provided at apr : gmt from carnegie mellon university ] https://doi.org/ . /bcc. . https://muse.jhu.edu/article/ https://doi.org/ . /bcc. . https://muse.jhu.edu/article/ • the bulletin easy to see why tretch might be attracted to him. however, the plotting falls short of coherent. random incidents follow one another, punctuated by stilted dialogue and choppy scenes that neither flow into one another nor connect thematically. for instance, after thinking about his great-uncle, a vietnam vet who took his own life, tretch goes out to stargaze on a frozen lake in the middle of the night and falls in, only to be rescued by his father, who happened to follow him. later, the boys are called on to help tretch’s squeamish farmer grandfather deliver a breech calf in the middle of the night, tretch makes up with a homophobic bully by yelling at him for smoking, and he then cuts a fine rug at a new year’s eve dance after coming out to his date. it’s hard to tell whether the bumpy dialogue is because the characters are not realistic or because they are too realistic for art, but ultimately this requires readers with a high tolerance for literary and character awkwardness. kc weingarten, lynn suicide notes from beautiful girls. simon pulse, p trade ed. isbn - - - - $ . e-book ed. isbn - - - - $ . r* gr. - despite not having talked to delia in over a year, june is devastated when she hears that her former best friend has committed suicide. she’s also suspicious, though: there’s no way that delia set herself aflame in her stepfather’s shed, since fire was the one thing that scared the normally fearless and fierce delia. she joins delia’s most recent boyfriend, jeremiah, in a search for clues to what they believe is delia’s murder. their investigation uncovers some of delia’s seedier activities over the last year, but ultimately, june’s hunt for answers points toward the one person she thought she could trust the most. the book earns its dramatic title, both in the plot’s hairpin twists and the portrait of an intimately toxic relationship between two desperate girls, illuminated through flashbacks that add dimension to both characters. delia seems at first to be a typical manic pixie dream girl, but she is far more clever and manipulative than june gives her credit for. june’s also oblivious to her own malleability when it comes to delia—she is comfortably ensconced in delia’s shadow when they are friends; unmoored but relieved in their separation; and guiltily determined in the aftermath of delia’s death, but never once does she realize that delia is always the motivation behind her behavior. weingarten is acutely aware of pacing—each plot turn is followed by a reprieve that allows readers to settle into a new theory about delia’s fate only to have their assumptions upended once again. a taut, sophisticated thriller, this will find an audience with teens who appreciate labyrinthine plots and ambiguous endings. kqg willems, mo i will take a nap!; written and illus. by mo willems. hyperion/ disney, p (elephant & piggie books) isbn - - - - $ . r gr. k- tired, cranky gerald wisely recognizes that a nap is just what he needs to feel good again, and he quickly settles into sleep with his blankie and knuffle bunny (from knuffle bunny, bccb / ). in his subsequent dream, piggie disturbs his nap, and gerald’s grouchy response to her interruption makes her so cranky that she, too, wants to take a restorative rest. her “special buddy” for napping is a stuffed elephant (which gerald finds endearing), and soon both pals are off to dreamland—until piggie’s snores keep gerald from sleeping. when gerald throws a fit about not being able to sleep and declares, “i am not enjoying my nap, piggie! i am not microsoft word - rbvm_beautypaper.docx munich personal repec archive beauty as a factor of economic and social development baggio, rodolfo and moretti, vincenzo bocconi university, giuseppe di vittorio foundation august online at https://mpra.ub.uni-muenchen.de/ / mpra paper no. , posted aug : utc beauty as a factor of economic and social development rodolfo baggio and vincenzo moretti dondena centre for research on social dynamics bocconi university, milan, italy rodolfo.baggio@unibocconi.it in charge of the society, culture and innovation section giuseppe di vittorio foundation, rome, italy v.moretti@fdv.cgil.it ==================== working paper, august  abstract: we discuss here how beauty can be considered a determinant for economic and social growth and what is its importance. we do this by following a line which links beauty with creativity and innovation; commonly reputed the main engines of development, especially in a globalized and highly technological and competitive world, in which many traditional differences in terms of space, time, size, and economic power have dramatically changed. keywords: innovation, creativity, beauty, economic and social growth, work well done beauty there is little doubt that beauty is a concept of great importance for human beings. in all areas, even those that might seem, to those who do not know them fully, cold and rational. so that, almost surprisingly, we find statements such as the one of the cosmologist janna levin (lethem & levin, ): something i find particularly interesting is that science, i think, is the last realm in which people talk to each other seriously, with a straight face, about beauty. visual artists would never say that’s a beautiful piece of  this is a revised and extended version of an article published online on nova‐ilsole ore in italian: http://nova.ilsole ore.com/frontiere/la‐bellezza‐che‐moltiplica‐lo‐svilluppo work, not in really contemporary, cutting-edge art. […] and it’s considered kind of provincial to aim for something beautiful. we’re not doing pretty pictures here; we’re doing something else. but in science, we really hold on to beauty and elegance as the goal because, for reasons that i think nobody fully understands, it’s a good criterion for distinguishing what’s right from what’s wrong. and if something is beautiful and elegant, it’s probably right. the examples of this view of beauty in science are quite numerous. in albert einstein began a revolution in physics, that was to lead to a view of the world completely different from that which had ruled for more than two centuries (from the publication of newton’s principia). its starting point is not the scrutiny of some experimental data, but the realization of the lack of symmetry of maxwell’s equations of electromagnetism. a strong call for simplicity and harmony in a set of mathematical relationships. a hymn to beauty is also the start of another revolutionary work: de revolutionibus orbium caelestium by nicolaus copernicus. it starts developing his proposal just from considerations of simplicity, symmetry and harmony, as stated at the very beginning: among the many various literary and artistic pursuits which invigorate men's minds, the strongest affection and utmost zeal should, i think, promote the studies concerned with the most beautiful objects, most deserving to be known. the relationship between beauty and scientific thought, however, is even richer and deeper, and comes from the observation of nature as a place of aesthetic experience. we realize that, mostly, beauty meets some criteria of symmetry and harmony, and that these can be described and represented in mathematical terms. this idea is so profoundly rooted in many scientists’ minds, that one can go as far as to say, as paul dirac ( : ): … it is more important to have beauty in one’s equations that to have them fit experiment. […] it seems that if one is working from the point of view of getting beauty in one’s equations, and if one has really a sound insight, one is on a sure line of progress. if there is not complete agreement between the results of one’s work and experiment, one should not allow oneself to be too discouraged, because the discrepancy may well be due to minor features that are not properly taken into account and that will get cleared up with further development of the theory. throughout the history of science, simplicity and elegance, the fundamental attributes of the concept of beauty, have a propelling crucial function. these concepts are closely related to the explanation of a phenomenon and the manner with which this explanation is formulated. the principle of parsimony, known as ockham's razor, according to which it is at least useless, if not harmful, to formulate more hypotheses than what is strictly necessary, may be taken as the theoretical basis for much modern scientific development. on the other hand, in a world often thought (wrongly) as an alternative to scientific knowledge, the world of arts with their many manifestations, the concept of beauty has a central role. in fact, despite the many definitions or attempts to define art, in any of its forms, its essence is in the (emotional) activity of creation and appreciation of beauty. so that, discussing some contemporary refusal of the concept, the critic roger kimball strongly makes the point ( : ): “this much, i think, is clear: without an allegiance to beauty, art degenerates into a caricature of itself; it is beauty that animates aesthetic experience, making it so seductive.” as claimed by morelli, in his mind and beauty (morelli, ), the analysis of the different forms of aesthetic experience highlights the close connection, mediated by the principle of imagination, between the human being, and the world around him and its structure. and, as we know, the system of relations, real or virtual, between individuals and between individuals and the environment in which they live, plays a key role in any human action. there seems to be a physiological reason for this appreciation of beauty. recent studies on human brain performed with functional magnetic resonance imaging (fmri), which allows to highlight areas of the brain activated in the presence of stimuli or during specific activities, show how important is the function played by mirror neurons, those elements that many researchers deem able to allow us to grasp on the fly what is happening around us, to empathize with the emotions of others, and, above all, to learn by imitation (cook et al., ). for some scholars, mirror neurons may even be the building blocks upon which the culture of a human being is founded, because the dissemination of knowledge would occur principally by imitation (ramachandran, ). in any case, these studies show a substantial equivalence, when aesthetic appreciation or creative impulse are concerned, in both the scientific and the artistic world (andreasen, ; zeki et al., ). in essence a human being (his brain) participates in the experience of beauty as if embedded in an open system that co-evolves with the dynamic environment in which it is immersed, and visual and auditory stimuli are the makers of aesthetic experience (welsh & di dio, ). recent research in neuroaesthetics (gallese & di dio, ), posits that this would happen by activating several groups of neurons that produce pleasing sensations, and, more importantly, create new connections between different areas of the brain, the reticular connections that form the basis of many creative processes (vartanian et al., ). one further consideration is in order before going on. beauty is often seen as a subjective feature (“it is in the eyes of the beholder”) and the debate on whether instead it is an objective feature is as long as the history of human thought. here we adopt the view that, even if matter of personal interpretation, beauty has an irreducibly social dimension. it is a view we share, or we want to share, and shared experiences of beauty are exceptionally intense forms of communication. in this interpretation, the beauty experience is not only confined to the mind of an individual, but connects people and objects in communities of appreciation, even small, but strongly cohesive in their views (sartwell, ). creativity and innovation creativity and innovation are, today, a widespread mantra when it comes to economic and social development. these features are identified as essential to ensure success, growth, improvement of material and spiritual life, happiness and well-being of individuals, companies, organizations and social systems (anderson et al., ; leckey, ; piergiovanni et al., ). they are increasingly seen as critical to the design of the elements that can make the difference between a successful product and the serial reproduction of overcrowded offers (richards, ). although not very well defined, creativity seems to have, as essential foundation, the ability to combine and recombine ideas or visions of reality. “good artists copy, great artists steal”, picasso is known to have stated, and in many academic fields is popular the adage: “copying one is plagiarism, copying many is research”. all statements of the fact that having a good amount of creativity means being able to seize, consciously or unconsciously, a set of different stimuli and to frame them into a solution for a problem or the design of a new object. this idea leads on to consider another phenomenon often closely related to creativity, and more or less based on the same elements: serendipity (moretti, b). genius, chance and context there is a strong connection between the drive for innovation that characterizes the current phase of development, and the concept of serendipity, defined by robert k. merton (merton & barber, : ) as “the fairly common experience of observing an unanticipated, anomalous and strategic datum which becomes the occasion for developing a new theory or for extending an existing theory.” according to merton ( : ), there is a “sociological importance of the unintended consequences of intended actions in social life generally and of unanticipated phases in the growth of knowledge “ and, as pointed out on several occasions, chance particularly favors the prepared mind operating in microenvironments that facilitate socio-cognitive interactions, and that can be described as a socio-cognitive serendipitous environments. given this background, our question now becomes: is it possible to imagine a different perspective, organizational rather than individual, that links the possibility of making discoveries by genius and chance with the capacity of organizations to establish rich interactive socio-cognitive environments, beyond the ability of a prepared mind to grasp unexpected anomalous data? and again, to what extent this perspective, with the consequent priority inversion, can promote further unprecedented developments in defining the concept of serendipity and its uses within the boundaries of scientific advancement? in our view, seriously considering this perspective means taking seriously, before all, the sociological character of serendipity and its relationship with the contexts, the organizational structures and the processes that encourage and determine development. the idea is that recognizing the limits of a psychological perspective or agreeing on the need to integrate it with the sociological one is not enough. we must reverse the approach and place the emphasis first on the resources made available to the network and on the active relationships between the different institutions (universities, research groups, innovators, etc.) and then on the preparation and the creativity of the individuals. of course, even a sociological perspective, as well as the psychological one, cannot be self-sufficient. it does not suffice, by itself, to account for the nature and processes of serendipity, but the thesis proposed here on the borders (and limitations) of the psychological perspective is inside the borders (and limits) of sociology and the two boundaries ‘do not match.’ geography, even before the history of scientific discoveries, can help to clarify the matter. two examples: the first one is the cavendish laboratory in cambridge, who has been home, for a considerable period of time, to nobel prize winners; the second one is the california institute of technology (more commonly known as caltech) in pasadena, california, in which as many as nobel prize winners have worked (the single laboratory of renato dulbecco hosted four: dulbecco and howard m. temin in , susumu tonegawa in , leland h. hartwell in ). creative processes as a social processes a consistent line of thought has begun to recognize the fact that a creative process is, at least partially, a social process. there is the idea that a group is more creative than isolated individuals, because their members bring different contributions, and their interactions favor creations more and better (john-steiner, ; paulus & nijstad, ). for this reason, some argue that, especially in a working milieu, environmental factors such as the support of a supervisor or influences resulting from an interaction are crucial for creativity (amabile, ). this is emphasized several times in a decisive manner by isacsoon in the innovators (isaacson, ) that traces the history of the development of information and communication technologies which, notoriously, were, and still are, examples of high creativity and innovation. innovation and creativity are based on what sociologists have called human capital, that set of knowledge, skills, abilities, emotions, acquired by an individual aimed to the attainment of social and economic objectives, individual or collective (coleman, ; subramaniam & youndt, ). but if these phenomena are social processes, they can be fully understood only by adding to the individual characteristics the consideration of the environmental conditions and the effects of the connections existing between the different individuals. this role is now well recognized, and bourdieu (bourdieu, ) extends the concept by defining social capital as (p. ): “the aggregate of the actual or potential resources which are linked to possession of a durable network of more or less institutionalized relationships of mutual acquaintance and recognition – or in other words, to membership in a group.” speaking of connections and social ties means adopting a systemic vision and considering the network that connects the different elements (people, groups, circles). this raises a discussion on which is the ideal network configuration for encouraging the emergence of creative ideas. many contrasting proposals have been made, but a convergence seems to come forward on the idea that the best solution is that of a network consisting of a series of cohesive communities, which then facilitate intense exchanges, that have connections, even very weak, between them, which would help the dissemination new ways of thinking, thus avoiding the risk of excessive closure of a connected , but isolated, community which would remain stuck on what flows inside (baggio, a; fleming & marx, ). in such a configuration, then, the availability of highly standardized infrastructures and technologies increases the possibility of recombining different elements and simplifies the exchange of information and knowledge (baggio, b). beauty, creativity and innovation if creativity, necessary basis for innovation, is largely linked to the individual’s ability to connect different elements, then we have to think that the elements that most affect the human mind are privileged in this process. among these factors, the aesthetic experience certainly has a significant influence. this happens not only when individual elements (objects, ideas etc.) are at play, but also, quite obviously, when beauty and aesthetic pleasantness characterize the environment surrounding an individual. a beautiful setting, being it natural or artificial (meaning ‘man-made’), seems to encourage creative development and innovation, as many state, especially in the field of architecture and city planning. this is the argument put forward for example by kaisa holloway cripps ( ) on the environment, but it also appears valid within individual workplaces (van marrewijk, ). empirical evidence that aesthetically pleasing visual stimuli increase the capacity of creative problem solving is quite solid. two factors are involved in this process: the structure of the brain that controls memory processes, and the individual knowledge and skills (goldschmidt, ). as richard florida argues in his book the rise of the creative class (florida, ), the basis of a favorable environment for creativity, and for fostering innovation, can be traced back to three elements: individual talent (education, skills, experience), a tolerant and multicultural environment, and the necessary technological infrastructures. godoe ( ) broadens the perspective redefining the utility (economic) which is the basis of many models on the dynamics of innovation, highlighting as key elements: aesthetic factors, serendipity and imagination, and, of course, creativity. in the author’s view the role of aesthetic factors defined as “the appeal and attraction associated with beauty” (p. ), is predominant. according to godoe ( : ): “the innovation problem is to find an admissible set of values (e.g., aesthetic factors and codes) of the command variable, compatible with constraints, which maximize the beauty [instead of simon’s ‘utility function’] for the given variables of the environmental variables.” innovation and socio-economic development the relationship between innovation and economic and social development is well known and studied, it is only worth to mention here just a few essentials. an oecd report (oecd, ) describes carefully the fact that the last decades have shown that innovation plays a central role in the economic development of many countries, even considering different forms and different approaches in the various stages of evolution. research on the subject is rich and many studies have good empirical evidence. the conclusions seem unanimous in holding the important contribution of innovation, and its quality and quantity, to economic growth. moreover, this close relationship is confirmed not only globally (at country or sectors level), but also at the level of individual organizations or companies, and is usually geographically bound (hasan & tucci, ). innovation is crucial not only for an economic development, but also plays an important role for the social system involved. this aspect is not always clearly shown, especially by economists, but is of enormous significance (maccallum et al., ). the central idea is that social innovation is about meeting not only material needs but also social relationships and a good management system must adjust the allocation of goods and services so as to satisfy both. this passes through a review of the forms and the structures of governance that should pay careful attention also to factors other than those usually considered. for example they should consider issues such as the creative and artistic milieu, the creation of social capital, the link with the territory. the opportunities offered by this approach seem very interesting especially because they look better development options, as an alternative to the current neoliberal economic vision, and emphasize socially important factors such as cooperation, cultural activities, solidarity and diversity. beauty and work well done a further consideration is in order here. it concerns a matter which, unfortunately, has been disregarded by too many parties for too a long time: the importance of doing things well because that’s how they should be done. the idea in this case is that without a profound cultural change in the approach to work, at every level, it is not possible to capture, and then multiply, the opportunities for development offered by the modern digital society. we definitely need to give more value to work, respecting the work and those who work. connecting own work to dignity, identity, sense of people, structures and organizational systems is more essential than ever, if we want to prevent the shadow of a flat future (martinelli et al., ). libero, one of the protagonists of head, heart and hands (moretti, ), would say that perhaps we “forget the effort it takes to make bread, to pull up a bridge, to pick tomatoes, to build a car. by keeping watching television some people think that we live in the world of copperfield the magician, voila! and things appear as if from nowhere. but behind everything there are the ability, the commitment, the hard work of those who make it.” in the era of internet and the knowledge society, the key for a change is more than ever right here, in the realization that any work makes sense and has a meaning if it is done properly (weick, ); in other words: “what’s ‘almost’ good doesn’t fit.” there is also an etymological connection between the idea of beauty and that of doing things well, given by the latin bellus, beautiful, which is short for an ancient form of bonus: good, well. beauty may be an opportunity (in the sense of the right time, kairos) to lengthen the shadow of the future on the present, to seize opportunities and multiply them. it can provide a different supporting structure, and put in place a new system of mutual relations, words, ideas, concepts, decisions, and actions aimed at the development. work should be associated with the concept of ‘respect’. a job well done should be seen as self-realization, both at individual and at systems, organization and country levels. under the same conditions, whatever they are, those who have chosen to do properly what they have to do are more relaxed, more satisfied, more able to design successful strategies and to adopt virtuous behaviors (individually and collectively). they progress their working conditions, and thus contribute positively to the social and economic environment in which they live. we like to think about the connections between ‘doing things well’ and ‘doing good things’ as the symptoms of a possibility to pay back culture, innovation, and future to the world. in essence, our argument is betting on the connections between doing things well and doing good things so that smart cities, resilient cities, digital cities, can have smart features and unmatched capabilities. the message is: let us rethink cities, regions, districts, be they industrial, social or cultural - as many italian centers - and let us reorganize, rebuild, re-evaluate them in the light of the opportunities offered by the modern advanced technologies: the internet of things, the internet of people, the internet of knowledge. we should start working concretely, enhancing and enriching the historical, cultural, environmental, natural, and productive environment. and we can do this by doing things well, making beautiful things, as has been done for centuries, in every corner of the world. in a world increasingly ‘condemned’ to find a distinctive, competitive advantage, the quid that a country, an institution, a company have as exclusive trait (or in excess with respect to all others), together with the improvement of territories and the emphasis on their beauty, can be the key to return to grow in a balanced way (sustainable some would say), both from an economic and a social point of view (moretti, a). hinged around the territory, the industrial revolution started with the advent of the internet of things (industrial internet, industry . ), and the internet of energy (reorganization of efficient buildings, reorganization of the public transport system, priority use of public goods, environmental protection, production and waste disposal), knits increasingly close relationships between the two ecosystems, digital and physical. this ensemble can have, in our and in many other countries, an enormous potential for development, starting from the ability to attract capitals (monetary and human). the territory (city, district, region) becomes the socio-economic context (scope, background) open and interconnected, able to give uniqueness, value, and competitive advantage to the italian way to work, fostering innovation, business creation, development (agriculture, industry, tourism, etc.), and liberating our enterprise culture from the constraints of family transmission. it can enhance and multiply its resources, with the objective to increase employment in both the ‘traditional’ and the more ‘innovative’ sectors in which new businesses are created (commonly said to be the main source of new jobs). the idea of triggering a new phase from companies and innovative start-ups can help make more explicit the link between job creation and business creation and can help to release the innovative traits of the same companies or start-ups from the (restricted) business sector in which they operate, and connect them with more significant elements such as skilled workforce, certified incubators, universities and research institutions. this would certainly improve the quality and quantity of transactions with medium and large enterprises and with industrial and financial investors. we have a dream bay of naples, the year of grace . fifty years after the establishment of the metropolitan area, the old naples appears literally transformed by the advent of the internet of things and the smart reconfiguration of the relationship between humans and generated by the dramatic development of digital technologies. the dream of experiencing a model centered on beauty as a multiplier of opportunities, as creator of sense, wealth and development (cultural, social and economic), as development of the immense human, cultural and social capitals available, and as promotion of good and active citizenship, has been superseded by reality. the city of bacoli, used by baggio and moretti in as an example of a waste of beauty (cuma the acropolis and the archaeological park; baia aragonese castle, the underwater remains of the roman baths and villa; sacellum in miseno; agrippina’s tomb, centum cellae and mirabile pool in bacoli, all in the same town and within a few kilometers), , is today, unequaled in the world, at the first place in the international ranking of high quality cultural tourism. in a few months the entire bay of naples – from sorrento to monte di procida, passing through the many agricultural areas, the three active volcanoes and the islands of capri, ischia and procida - will be proposed to the plenum of the interplanetary council of the galaxy as good practice to be studied and used in order to activate the necessary isomorphism processes. a few years more and the objective of ensuring beauty and prosperity to all the people of our beloved earth will have been realized. concluding remarks this is for now only a dream, but the beauty equation: job well done - creativity - innovation - development seems to hold, at least according to the qualitative reasoning and logical-deductive line followed so far. actually, more than of an equation we should speak of a system of equations and, what is more, of a system with an unspecified number of equations. in fact, there are numerous factors that should be considered and that can contribute to the solution. as noted, whatever the territory we consider, we should add to the equation the basic parameters involving the efficiency of physical infrastructure (communications, economic and financial), the structure of social relations, and, as well highlighted by some research (baggio, a, b), we should also add a system of effective governance. assessing these impacts is not easy, primarily because the metrics to evaluate these factors and the relationships between them are virtually nonexistent. help will come probably only by the use of simulation techniques that allow, as already happens in many fields, to build scenarios and analyze their consequences (axelrod, ; henrickson & mckelvey, ). on this we can and will work in the future. in the meantime we feel satisfied from having shown that the fundamental equation at the base of our research program holds well. references amabile, t. m. 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( ). the experience of mathematical beauty and its neural correlates. frontiers in human neuroscience, , art. . wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ ucl discovery close ucl home prospective students current students staff ucl discovery home a nascent retina, generated from a d embryonic stem cell culture home main navigation items lists can be nested lists can be nested main navigation items home students staff nhs visitors electronic resources libraries and study spaces opening hours open access research data management bibliometrics special collections, archives & exhibitions getting help & contacting us about us home main navigation items main navigation items home home ioe eprints notice ioe eprints is now part of ucl discovery. your page will load within seconds. if your page does not load, please click here. sidebar supporting content, patterns or related links can be placed in the sidebar facilities faculties and departments library museums and collections ucl bloomsbury theatre maps and buildings locations ucl and london ucl australia ucl qatar ucl global connect with us alumni businesses media relations jobs give to ucl university college london, gower street, london, wc e bt tel: + ( ) copyright © ucl disclaimer freedom of information accessibility privacy cookies contact us department of economics working paper series productivity or discrimination? beauty and the exams. giam pietro cipriani, angelo zago wp number: december issn: - productivity or discrimination? beauty and the exams giam pietro cipriani & angelo zago department of economics, university of verona, italy abstract do good looks make people more productive? an impact of looks on earnings has been found in the empirical literature: plain people earn less than average-looking people who earn less than the good-looking. however, an important question remains unanswered: is the impact of beauty due to pure discrimination or productivity? we provide evidence against the hypothesis of becker-type discrimination stemming from tastes and in favor of productivity-related discrimination. jel: j ; i . keywords: physical appearance; discrimination; productivity. we thank the university of xx for kindly providing the data. g. perrucci and n. tommasi provided excellent support in preparing the data. we received helpful comments from d. lubian, m. menon, and especially e. cannon. i. introduction following on the seminal paper by becker ( ) on discrimination, there has been a vast empirical literature measuring differences in earnings or other labor markets outcomes between different groups of workers. the impact of appearance on wages is now quite well documented. for instance, weight seems to be affecting mainly female wages, with a wage penalty for obese women (averett and korenman, ). persico et al. ( ) explain the origin of the “height premium”, i.e., the increase in wage that goes with an additional inch of height, and find that it is the height at teens age that essentially determines the returns to height. recent research has studied how physical appearance, i.e., beauty, affects labor markets outcomes. however, this task is usually complicated by the fact that different groups may have different productivities. hamermesh and biddle (h&b, ) and biddle and hamermesh ( ) found evidence that beauty affects earnings irrespective of gender. they also found that the labor market sorts the best-looking people into occupations where looks are likely to be more important (hence productive), but this latter evidence is rather weak. using physical appearance as a possible source of discrimination makes it easier to distinguish labor-market outcomes arising from discrimination against a group (the homely in this case) from those produced by unobserved productivity. in fact, it can be argued that there are activities in which appearance is more important and where the payoff to beauty then reflects productivity, and other jobs where any such payoff reflects pure discrimination. similarly, for the uk labor market, harper ( ) found that physical appearance has a substantial effect on earnings. he also found that beauty has a very significant impact in the marriage market. however all these studies, like many others on the effects of various ascriptive characteristics on wages, find it difficult to distinguish whether the wage differential is due to becker-type discrimination stemming from tastes or to differences in productivity. indeed, “.. it is very difficult to construct a research design that allows one to distinguish labor-market outcomes arising from discrimination against a group from those produced by intergroup differences in unobserved (by the researcher) productivity..” (h&b, : ). in an attempt to disentangle these effects, a recent paper by pfann et al. ( ) on a sample of dutch advertising firms finds that those with better-looking executives have higher revenues and hence pay them more. however, the fact that beauty is highly productive in the advertising sector may not come as a surprise. another paper by hamermesh and parker (h&p, ) shows that lecturers who are viewed as better looking receive higher instructional ratings by their students. then, ceteris paribus, these higher ratings translate into higher salaries, because us university administrators pay attention also to teaching quality in setting salaries. however, the question remains on whether students are simply discriminating against ugly professors by reacting to an irrelevant characteristic, or if they do really learn less from them. and again, more generally, “... disentangling the effects of differential outcomes resulting from productivity differences and those resulting from discrimination is extremely difficult in all cases …” (h&p, : ). this paper is a contribution to the debate on whether the labor market outcome of ascriptive characteristics represents productivity or discrimination. using a rich set of data from the college of economics at the university of xx, we examine the effects of students’ physical appearance on examination results. we find evidence that beauty has a significant impact on academic performance, a result which is consistent with and comparable to the impact found in the labor market literature. in addition, since we can compare student performances in oral and written exams, where in the latter the evaluation is blind, i.e., not influenced by physical appearance, we can in fact understand better the source of the “beauty premium”, that is disentangle productivity from discrimination effects. we find that the effect of beauty on academic performance cannot be ascribed to pure professor discrimination. one could then argue that to the extent that wages rise with educational attainments, our findings corroborate the hypothesis that the payoffs to beauty reflect differences in productivity. the paper is organized as follows. section ii describes the working of university system for students in italy and the dataset that we use to analyze the role of looks. section iii presents the main empirical results of the paper, first showing the impact of beauty on students’ performance and then disentangling the discrimination and productivity effects. section iv briefly discusses some possible explanations based on psychological and economic theories which help to interpret our results. section v concludes the paper. ii. data and institutional details in the - academic year, a substantial reform of university degrees took place in italy. in order to make university education more suitable for the job market and to improve on graduation rates, the official duration of undergraduate degrees was reduced from to years. according to the ministry of university, this would make the italian university degrees (laurea) more comparable with analogous degrees in other european countries, as agreed with the bologna convention among eu education ministers. in addition, in the new system more motivated students can further acquire education by adding more years to obtain a specialized degree, the laurea specialistica, and then enter into phd programs. students enrolled at the college of economics at the university of xx, like those in most italian universities, are offered two types of examinations, verbal or written. each professor is free to choose whether to set an oral or a written exam. in some cases the exam is both oral and written, but only a final mark (sometimes the average, some other times other combinations) is recorded. in addition, in italian universities students are allowed to take examinations many times during the academic year, and it may happen that a student attending a class can take the exam either at the end of the course or in other dates during the following months or even years. therefore there is more than one examination session in the academic year and in each session a student can take (almost) as many exams as he/she likes. in the period under consideration, in the college of economics there were sessions every year. the winter session, held in january and february, was about week long, and the exams for each course were delivered at three different dates, at least two-week apart; the summer session, in june and july, about - week long, in which again for each course students had the opportunity to take exams three times; and the fall session, shorter ( weeks), in which exams were delivered only one or at most two times per course. therefore, every year students had the opportunity to find to dates at which to take the exams for each course. the exam evaluation and grading is based on grades with a scale going from to (with cum laude being awarded in some cases) and the pass threshold set at . however no mark is ever recorded when below . if students fail an exam, i.e., they get a grade below , there is no official record of the event (nor even that they have attempted), and they can take the exam again some other time. when marks are released, but before they in italian universities, on average, the drop out rate under the old system was %. the average time spent to complete a first degree was years and only . % of students graduated on time. with the new system of three-year degrees provisional results show that % of students graduate on time, that is within . years (istat, ). are recorded, students can refuse to register the mark in order to re-take the exam in the future and perhaps get a higher mark. in this case, again, there is no record of the first attempt. finally, there is no upper limit on the number of years students can take to finish their degree. in order to graduate, however, a student has to pass a certain number of exams. moreover, the final grade coming with the awarded degree is calculated on the basis of the simple average of grades obtained during the academic career. table presents the statistics describing our variables. we have collected data on the cohort of students at the college of economics at the university of xx registered for their first time in the academic year - , observed over three years. there are students in the dataset, . % of which are female. in our dataset we have data on the type of high school they attended, on the high school final grades, the date of birth, and the home address. we also obtained detailed information about each student’s academic curriculum with examination dates and marks. our dataset records all individual grades up to the summer session. in theory, since the official duration of their course was years, by that session any student in our cohort could have graduated. however, a negligible number of students - only - did actually graduate. some students will have graduated over the following months, and many more will graduate in and later years, when they complete all the required exams. quite a lot of them, however, will never graduate. [insert table about here] for each student, photo-id pictures were also available. each of the student’s pictures was rated by each of five professors: women and men aged respectively , , , , (to accord with the age and sex distribution of university professors in the college). the raters viewed all photographs on a high resolution computer screen, one by one, and could tick beauty on a (highest) to rating scale. of course, the ideal measure of beauty would account for all of a person’s features capable of making a visual impact on the observer and not just the facial features. however, the error this may introduce in the beauty measure is unlikely to be systematically related to any of the variables we focus on. also, jackson ( ) has shown that there is a high correlation between responses to still photographs and responses to video tapes of the same stimulus person. finally, the cited literature on the economics of beauty has always used still photographs. in the years under consideration, the required number of courses and hence exams was . they were instructed to use for average look, and for respectively better and worse than average, and for respectively the beautiful or handsome and the homely. they were allowed to move back to previously rated photographs to change or check their ratings. in a series of pair-wise correlations, we found correlations from . to . between panel members, always highly significant, and given the number of pictures this seems to suggest a substantial agreement among evaluators about the appearance of individuals, thus confirming the existence of common standards of beauty, as found in the rest of the literature. for the beauty index we will use, however, we standardized each rater’s evaluation and then created a composite standardized beauty measure for each student by summing the five standardized ratings. iii. looks and the exams the tuition fees for public universities in italy are rather low, and thus it is quite common that many students are enrolled at university without actually taking exams. in our cohort about % of the students have not passed a single exam. these may be students who have never taken an exam, for example because they enrolled just out of high school while looking for a job and then found one, or they may be students who have never passed an exam despite attempting. although, as already explained, we do not have official university records of students’ failed attempts, evidence collected from colleagues teaching first year courses suggest that about % to % of students fail each time. this seems to suggest that a large portion of “non participating”, i.e., not taking exams, students are actually participating but do fail. an important aspect of this study is to investigate the effect, if any, of the physical appearance on the performance of students. hence, we consider the impact of beauty on an indicator of performance that takes into account both the number and the grades of the passed exams using a series of regressions that we present in the next section. in addition, in the sections that follow, we further investigate this issue by looking at the effects on the number of exams and on the average grade obtained separately, plus some other variables that allow us to distinguish between the impact of beauty due to discrimination and productivity. preliminary to our analysis we run a probit regression on the participation of students, i.e., having or not passed any exam. the result show that whether or not exams are taken is dependent upon beauty. therefore, using ols on the number of exams taken only for those students for whom this number is positive gives downwards biased results. about euro per year at the university under consideration, with similar levels for other italian public universities as well. also, the number of exams, as well as our index of performace described in the next section, are censored variables where observations are clustered at a lower threshold (zero or eighteen) since no mark is ever recorded below the pass mark. since in principle marks could take on values below eighteen but we do not observe them because of censoring, we employ tobit estimates using all students in the sample. iii. evidence of the “beauty premium” as a primary index of performance we use a composite index of the number of exams times the average grade, which is equivalent to the cumulative sum of the grades of the exams passed by the student (checchi and pravettoni, ): , n n i i i i ij ij j ji perf n g n g g n ? ? Ã Ô ? © ? © © ?Ä Õ Å Ö Â Â where ni is the number of exams passed by student i, ig is the average grade, and gij is the grade obtained in the j-th exam. notice that italian students need to pass successfully a given number of exams before being awarded their laurea. the final grade however is proportional to the grades obtained in all the exams during the academic career and hence a student trying to finish her studies in a shorter time may be able to do it at the expense of a lower average and hence final grade. since we are considering the records of each student taken at the end of their third year, our composite index takes into account both the ability to be fast, i.e., to do a greater number of exams and hence to finish earlier, and to have good grades. at this stage we are interested on whether physical appearance has an impact on performance and hence we estimate the following: log , i i i i perf x bd i g? - - where xi is a vector of student i’s characteristics and bi is the student’s index of physical attractiveness. as explained before, since all performances below (one exam times the lowest recorded mark of ) are not registered, we need to employ tobit estimation of students’ performance on their set of characteristics to take truncation into account. according to our results (table ), better looking students perform better in the exams: the coefficient is positive and highly significant (at %). moving from one standard estimates are available from the authors upon request. deviation below the mean to one standard deviation above leads to an increase in the performance of about %. hence there appears to be evidence that beauty – as already found in labor markets, where it affects wages – can affect performance. in addition, the magnitude seems comparable to what is found in labor market studies. for instance, h&b ( ), using data from north-america, found pay premium for above average looking people of about - % and pay penalties for below average looking people of - %, according to the available dataset. harper ( ), using uk data, found a pay penalty ranging from % to . % for unattractive men and around . % for unattractive women. [insert table about here] before testing for the robustness of this result, however, we look also at the effect of other characteristics on students’ performances. being just out of high school (year_ ), on the other hand, increases the probability of doing better at university. this effect may be related to the fact that these students are in a sense just “minted” (fresh of studies) and hence may find it easier to pass exams. alternatively, and more likely, these students in fact do not participate yet in the labor market, and hence their opportunity cost of studying may be lower than part-time students, i.e., those that have already a job. in other words, these students may have acquired and not yet forgotten the right skills to succeed in school, or more likely, fresh graduates may have fewer occupation opportunities and hence may happen to be full-time students and be less distracted by work duties from their academic career. a similar effect is related to the type of high school the students were enrolled before going to university. it appears that students who attended a “liceo”, i.e., a high school that gives a general purpose education, either in the humanities, sciences, liberal arts, or languages, are better performers than student coming from professional schools. indeed, professional schools are known for being less demanding on their students while the curriculum is more rigorous and demanding in a liceo. technical schools are more demanding than a professional school and less than liceo, however the corresponding dummy variable is not significantly different from zero. the students coming from liceo have probably fewer opportunities in the labor market in the short run, at least compared to students graduated from technical or professional high schools, and hence their opportunity cost of studying may be implicitly lower. although we would need to have more information, for instance on family background, to explain in the north-east of italy, the unemployment rate is quite low (about . %), even among young people ( . % for - and only . % for - year old). educational choices and students’ performances, notice that the type of high school chosen is in fact related to family background, especially income levels and parents occupation and class, e.g., working or middle class. middle class families, indeed, tend to send their children to liceo, known for being better equipped to prepare students for universities, where they expect their children will go after high school. on the other hand, working class families may prefer technical schools, known for providing an education better suited for the job market after school. in other words, the choice of the type of schools may reflect, to some extent, the family economic and educational background. given the same family background, moreover, the choice of the type of school may reflect sorting of students based on their educational abilities: other things equal, students going to professional schools may be expected to be less performing on educational matters. for this reason, the choice of the type of school attended may also partially pick up students’ ability. a better proxy for student ability, however, is the final grade, i.e., the graduation grade, from high school. as one would expect, its impact is positive and highly significant on students’ performances. to the extent that this grade reflects students’ abilities, one can conclude that the more able students coming out of high school also perform better at university. another variable that significantly affects students’ performance is the final grade obtained in the state exams at the end of high school. this variable is very likely related to students’ ability and it is not surprising to find a significant effect, which is also the biggest in magnitude among the variables used in these regressions. we also considered a dummy variable (eci) for those students enrolled within the same college but in a degree program managed in a nearby city. this degree program differs in terms of facilities (there are less) and, in part, teaching faculty (more junior, part-time or temporary). the dummy is always significant and positive in this and all the subsequent estimates, meaning either that students enrolled in this program have better abilities or, more likely, that exams there may be relatively easier to pass. the dummy for gender is not significant. however, when estimating separate regressions for males and females, we find a positive and significant effect of beauty only for males, confirming what is found in the labor markets literature. looking at other regressor, characteristic that has an impact on performance but only for males and at the % level, is the fact that the student is resident in the area where the course is offered (resident). if we believe that a student who decides to enroll into a course offered in her own town (province in our case) may be less motivated than a student who decides to enroll into a course in another city, we have to expect that the resident student may have lower performances. as can be seen from table , the coefficient is indeed negative. it is interesting to investigate on whether there is a premium for being handsome or a penalty for being homely and if these two effects are in fact symmetrical. in the literature indeed there have been different findings. h&b ( ), analyzing us data and estimating human capital-type earnings equations, found that penalty for unattractive people were greater than premiums for attractive people. the same authors, using canadian data, however found that premium were larger than penalties, with these latter being insignificant. harper ( ), using data from the uk job market, found a larger penalty for unattractiveness than h&b ( ). we construct a dummy (handsome) for the top % most beautiful students and another (homely) for the bottom % least beautiful students and estimate separate regressions for males and females. as it appears from the last two columns of table , there is a significant penalty for being homely for male students since being in the bottom % reduces our index of performance to % below the average. on the other hand, the premium is small and insignificant for males and only significant at % for female students. in summary, we have shown that physical appearance has a significant and economically meaningful effect on the performance of students. first of all, being handsome increases the probability that a student in fact takes and pass exams. second, and more important for us, better looking students have better performances than other students. last, we find that the premium for beauty is smaller than the penalty for ugliness. while less economically important than the effects of the proxies for education and ability, these impacts seem quite significant, as already observed in the literature on labor market outcomes. we now turn to investigating on whether the increase in performance is related to different students’ productivity or to discrimination. iii. it’s not discrimination, is it? in this section we wish to determine whether the effect of beauty on student’s performance is the result of unobserved productivity or of pure discrimination by professors. if we can reject pure discrimination, one can safely assume that the effects of beauty on performance may be explained by different students’ productivity. to investigate the presence of pure discrimination effects we proceed in different steps. first, as a preliminary check, we look at the effects of beauty separately on the average grade and on the number of exams passed. while the discrimination effect of beauty may be at work in obtaining higher grades – teachers could be influenced by physical appearance when they can actually see it – it is less clear how it would influence the number of exams passed. the number of exams taken and passed is more the result of students’ choices and effort, and so could perhaps reflect more productivity than discrimination. second, we exploit the type of examination – either oral or written – to disentangle the effect of beauty. given that in written examinations physical appearance is unnoticed, our dataset should allow us to see if there is some support to the hypothesis of pure discrimination. if look had a (positive) impact on oral exams grades but were unimportant in written exams, then we could start asking whether these different effects where due to discrimination or whether the type of examination, in the case of the oral exam, was such to disadvantage homely people who may just be less confident and under perform in an oral exam. an important variable in our dataset is thus the number of exams that each student has taken in the period under consideration (almost years). as explained in the previous section ii, this is partly a choice variable, partly the result of students’ effort and ability, in the sense that students graduate when they have passed a given number of exams, but there is no lower limit on the number of exams that must be taken each year and a student is allowed to stay enrolled for as many years as he chooses to. again, since students may in fact have taken exams but not passed them, we need to use tobit analysis. we then estimate the following equation: , i i i i n x bd i g? - - and table reports the results of the tobit estimations of the number of exams passed (ni) on different students characteristics. physical appearance is significant, like other variables such as the dummies for the type of high school completed, being just out of high school, and not being resident at the university’s location, confirming again the results found for the composite performance index. the dummy for being a male student is not significant in explaining students’ performances in terms of number of exams. however, performing separate regression for each gender, we find that physical appearance is significant only for male students. moving from one standard deviation below the mean to one standard deviation above increases the number of exams passed by about % with respect to the mean. this result confirms the impact of beauty on the composite index of performance already seen before, both in significance and in the order of magnitude. the number of exams passed in the interval considered is a clear measure of productivity and thus we believe this is a first signal that beauty has a productivity effect. the other variable related to performance that we employ is the exams average grade and thus we estimate the following: , i i i i g x bd i g? - - where i g is the average grade, obtained in the exams. this measure of performance is censored too. indeed, the grades are on a scale between and , but in order to pass an exam the minimum grade is , and it is a general practice that only the grades equal or above are registered, while in case of failing the exams, i.e., grades below , these are censored. to control for this we use a tobit regression model. as before, beauty does not seem to have any significant effect for females, while it is significantly different from zero for males even though its impact is not high. the dummies for the type of high school attended before enrolling at university plus the final high school grade are also significant. following the second path in our investigation, we look at the, possibly differential, impact of beauty on written and oral examinations. in the years under consideration, exams were to be passed in order to graduate and obtain the laurea. however, the average number of exams passed by active students, i.e., those who took at least one exam, was just below , and only ten students actually finished all the exams and graduated. thus, even though the type of exam for each course – either written or oral – is a choice of the professor, which exams to take first is decided by the student. in table we report the results of tobit regressions on the number of written and oral exams respectively. the impact of beauty for males appears to be positive for both type of exams, but more important for written examinations where an identical increase in beauty increase almost twice as much the number of exams. if we believe in a pure discrimination effect of beauty, we would expect, if any, that handsome students would take more oral exams, where their beauty could be appreciated. since we find the opposite result, i.e., that beauty has more of an impact on the number of written exams, we believe this gives more support to the productivity hypothesis and less to the pure discrimination hypothesis. looking at the average grades for written and oral exams, in table , we find that the beauty coefficient is significant for both oral and written exams average grades. again the effect is stronger on written exams. we believe that if beauty had a pure discrimination effect, we should find a greater impact of beauty on the oral exams average grades, which we do not. again, the (lack of) evidence in this last set of regressions appears to be more consistent with a productivity effect of beauty. we also investigate whether beauty has any impact on students’ differences in performances between oral and written exams by estimating the following: , i i i i perf x bd i gf ? - - where fperfi is the difference in performance between oral and written exams. the performances in this case are measured in terms of average grades and number of exams, as we will describe shortly. in general, if we believe in the pure discrimination effect of beauty, we should expect a better performance of good looking students in oral exams, especially in terms of average grades. in other words, if students show better performances in oral exams and beauty is found to have a positive and significant impact on it, i.e., ,i @ there would be some evidence of discrimination. in table we report the results of an ols regression on the differences between the average grades obtained in oral and written exams on the usual explanatory variables. beauty’s coefficient is not significantly different from zero, as almost all other explanatory variables. in the same table, we also look at the impact of beauty on the difference between the number of oral and written exams passed by the students. to be consistent with a discrimination type of explanation for the effects of beauty on performances, we would expect i > , i.e., more handsome people doing more oral exams. instead, we find that when there is an effect of beauty, in the regression for males, this is in fact negative, meaning that better looking students have passed more written exams. again, if any, we believe that this evidence would be consistent with a productivity effect of beauty. to summarize, we believe that we have evidence that allows us to reject the pure discrimination effect of beauty on performance. instead, given that in our dataset beauty does in fact affect students’ performances at university, we argue that we can opt for a productivity type of explanation: more handsome students are also more productive. we explore possible explanations for this result in the following section. incidentally, this result seems to provide support to the theory that society has higher expectations on the performance of beautiful people compared to the rest. given these expectations, an average performance by iv. discussion: why is better looking also smarter? this research has found a relationship between attractiveness and an index of performance. the motivation of our study was the economic literature on beauty and the labour market and its startling result that looks have a clear impact on earnings. an important unanswered question in the literature is asked directly by daniel s. hamermesh when he describes his research on the economics of beauty: “do good looks make people more productive – can we ever distinguish between the effects of beauty, or some other characteristic, as discrimination or productivity?”. by distinguishing between oral exams (where beauty is observed) and written exams (where it is not), this paper has not found any direct evidence for discrimination, a result similar to experimental economics evidence that ruled out any becker-type discrimination effect (mobius and rosenblat, ). thus our evidence suggests that good looks could make people more productive. in this section we will discuss some of the existing literature on the effects of facial attractiveness in order to find a possible explanation for the positive relationship between beauty and productivity, starting with the non-economic literature. a very comprehensive review of the literature is that by langlois et al. ( ) which conducts a quantitative review of the effects of facial attractiveness using hundreds of papers from published and unpublished sources from to . this article concludes that: ) beauty is not in the eye of the beholder, i.e., contrary to conventional wisdom there is a common standard of beauty both within and across cultures. ) people do judge a book by its cover, i.e., attractive adults and children are judged more favourably and treated more positively than unattractive adults and children, even by those who know them. ) beauty is not only skin deep, i.e., although both attractive and less attractive individuals exhibit positive behaviours and traits, attractive individuals tend to exhibit more positive behaviours and traits than unattractive individuals. another important contribution of the aforementioned paper is to discuss the various theoretical mechanisms explaining why beauty influences judgment, treatment and behaviour. in this respect, the literature distinguishes between social expectancy theories and fitness-related evolutionary theories. the first set of theories is based on the assumptions that cultural norms and experience influence the behaviour of both targets and them is penalized. for a discussion of these effects in a public good experiment see andreoni and petrie ( ). perceivers and that social stereotypes create their own reality (like a self-fulfilling prophecy). the second set of theories posits that morphological characteristics are indicators of fitness, health, quality and reproductive value. according to this second group of theories, beauty is an important aspect in human relations which operates through channels like mate selection and differential parental solicitude. while the first channel makes no predictions regarding the importance of attractiveness for children, since they are clearly not involved in selecting a mate, the second channel could be designed to explain children’s behaviour. in fact, it posits that if attractiveness is perceived as an indicator of quality, adults should invest more in attractive than unattractive children to enhance their own reproductive success. based on their review of the literature, langlois et al. ( ) concludes that although predictions from both social expectancy and fitness-related evolutionary theories are partially supported, neither theory is totally successful in predicting the various findings, and much additional research is needed before we can find how and why facial attractiveness influences social behaviour and development. recent economic literature recognizes the growing consensus that physical attributes, e.g., beauty and height, can affect the acquisition of non-cognitive skills. these latter represent a form of human capital and contribute substantially to labor market success. heckman ( ), for instance, reports evidence that preschool programs improve students’ social skills and motivation and hence can raise lifetime earnings. persico et al. ( ) found that about half of the “height premium” in the labor market can be accounted for by variation in participation in school sponsored non academic activities. being tall as an adolescent, they conclude, facilitates the acquisition of some form of human capital, like social adaptability, confidence and the ability to interact socially with others. in a recent paper, mobius and rosenblat ( ) report the results of an experimental labor market study decomposing the beauty premium and identifying three channels through which physical attractiveness can raise an employer’s estimate of a worker’s ability. since the confidence channel influences workers’ beliefs, they show that better looking workers are substantially more self-confident. their paper is thus consistent with the psychological and economic research and the anecdotal evidence emphasizing that “... people do recognize the income-enhancing effects of confidence ...” and thus “... the need for positive-thinking and for self-esteem as one key to success ...” (mobius and rosenblat, : ). see his homepage at http://www.eco.utexas.edu/faculty/hamermesh/beautyblurb.htm in a theoretical paper, benabou and tirole ( ) analyze the value placed by bayesian rational agents on self-confidence and its effects in enhancing motivation. indeed, self- confidence is valuable to the extent that it improves the individual’s motivation to undertake projects and persevere in the pursuit of her goals. ability and effort may interact in determining performance: in most instances they are complements, and so a higher self- confidence improves the motivation to act. in addition, people have imperfect knowledge of their own skills and abilities, and standard observation shows that morale plays an important role in difficult endeavors. this recent theoretical literature thus accomplish to model the influence of behavioral traits, to be distinguished from cognitive ability, i.e., more productive skills that can be acquired through education or proper training, on earnings differentials. indeed, as bowles et al. ( ) emphasize, seemingly irrelevant characteristics such as height, beauty, obesity have a potential role as reliable predictors of earnings. to conclude and summarize, we view these theories as important in explaining our results. if beauty has an effect on performance, and one can rule out pure becker-type discrimination as we do, the hypothesis that good looks make people more productive finds some support in these theoretical mechanisms. essentially the higher productivity of attractive people could be the result of pure discrimination in the past because of different parental (and teacher) solicitude or of past and current social stereotypes that affect self- esteem and motivation and hence productivity via a self-fulfilling prophecy. we view the fact that we can rule out another important possibility, i.e., that differential attractiveness can simply influence professor appraisals of students’ performance though pure discrimination, as an important result of our paper. given this perspective, one can relate our results to complement the received literature on the effects of beauty in the labour market. if differential productivity at the university translates in differential productivity at work, differences in wages arising from differences in attractiveness could also be the result of different performances. in other words, the proportion of wage differential that can be attributed to greater productivity as opposed to discrimination may be higher than what is implied by the literature. v. conclusions as noted by langlois et al. the question of why and how stereotypes based on attractiveness originated in the first place remains unanswered. we conduct an empirical analysis using a large dataset of students’ records and find evidence of a positive impact of facial attractiveness on their performance at the university. this is in line with the results of a number of papers in the labor literature which find that workers’ looks have a positive impact on their earnings. the main results of our empirical analysis are three: ) the impact of beauty is positive and significant in the decision to participate, that is to sit and pass exams once enrolled at the university. ) beauty affects significantly and positively the performance of active students, i.e., students who chooses to sit exams. ) distinguishing between oral exams (where beauty can be observed by the professors) and written exams (where it cannot be observed) allows us to reject the hypothesis of pure becker-type discrimination based on beauty and stemming from professorial tastes. the paper concludes with a brief discussion of the theories advanced by the psychological and economic literature to explain why attractiveness may influence productivity. references andreoni, j. and r. petrie, . beauty, gender and stereotypes: evidence from laboratory experiments, mimeo, university of wisconsin. averett, s. and s. korenman, . the economic reality of the beauty myth, journal of human resources, , , - . becker, g., . the economics of discrimination, chicago university press, chicago. benabou, r and j. tirole, . self-confidence and personal motivation, quarterly journal of economics, , , - . biddle, j.e. and d.s. hamermesh, . beauty, productivity, and discrimination: lawyers’ looks and lucre, journal of labor economics, , , - . bowles, s., h. gintis and m. osborne, . the determinants of earnings: a behavioral approach, journal of economic literature, , - . checchi, d. and g. pravettoni, . self–esteem and educational attainment, working paper . , dipartimento di economia e politica aziendale, university of milano. hamermesh, d.s. and j.e. biddle, . beauty and the labor market, american economic review, , , - . hamermesh, d.s. and a.m. parker, . beauty in the classroom: professors’ pulchritude and putative pedagogical productivity, nber working paper series, # . harper, b., . beauty, stature and the labour market: a british cohort study, oxford bulletin of economics and statistics, , - . heckman, j.j., . policies to foster human capital, research in economics, , - . jackson, l.a., . physical appearance and gender. albany, ny: state university of new york press. langlois j.h., l. kalakanis, a.j. rubenstein, a. larson, m. hallam and m.smooth, . maxims or myths of beauty? a meta-analytic and theoretical review, psychological bulletin, , - . mobius m.m. and t.s. rosenblat, . why beauty matters, mimeo, wesleyan university, ct. persico n., a. postlewaite and d. silverman, . the effect of adolescent experience on labor market outcomes: the case of height, journal of political economy, , , - . pfann, g.a.; biddle, j.e.; hamermesh, d.s. and c.m. bosman. . business success and businesses’ beauty capital, economics letters, , - . sleeping beauty and the dynamics of de se beliefs christopher j. g. meacham introduction take beliefs to be narrowly psychological. then there are two types of beliefs. first, there are beliefs about what the world is like, or de dicto beliefs. taking a proposition to be a set of possible worlds, the objects of de dicto beliefs are propositions. to believe a proposition is to believe that your world is one of the worlds that form that proposition. so the proposition that there are extraterrestrials is the set of worlds in which there are extraterrestrials, and to believe that there are extraterrestrials is to believe that your world is one of these worlds. but not all beliefs are beliefs in propositions. take a world where two wise sages live, zorn and xingu. both sages know which world they’re in, and thus which propositions are true. the two sages live on different planets, but the planets are qualitatively identical. furthermore, the sages themselves are qualitatively identical. now, both sages can’t have true beliefs about which sage they are. the two sages are qualitatively identical, so if zorn believes he is zorn, so does xingu. if both sages believe that they’re zorn, then xingu has a false belief, even though all his propositional i borrow liberally here from david lewis ( ). in addition to assuming beliefs are in the head, i’ll follow lewis in ignoring difficulties that arise from mathematical or logical truths, and in assuming that the subjects of belief attitudes only exist at one world. i employ lewis’ framework for its elegance, but i think most of my substantive points don’t depend on it. in particular, note that nothing depends on the outcome of the internalist/externalist debate. it might be that the best candidate for the meaning of ‘belief’ is one where beliefs aren’t in the head, as the externalists claim. in any case, there is also another, if less eligible, candidate for the meaning of ‘belief’ where beliefs are in the head. call the first candidate belief , the second belief , and take me to be talking about beliefs . beliefs are true. so not all beliefs are propositional. over and above beliefs about what the world is like, there are beliefs about where one is in the world. beliefs broadly construed are de se beliefs. a centered world is a possible world paired with a designated individual and a time. a centered proposition is a set of centered worlds. the objects of de se beliefs are centered propositions. to believe a centered proposition is to believe that your centered world—who and when you are, and in what world—is one of the centered worlds that form that centered proposition. we can turn any proposition or set of worlds into an equivalent centered proposition or set of centered worlds, by replacing each world with all the centered worlds at that world. thus all de dicto beliefs are reducible to de se beliefs. of course, not all de se beliefs are reducible to de dicto beliefs. de se beliefs that aren’t reducible to de dicto beliefs are self-locating or irreducibly de se beliefs. in his influential article “attitudes de dicto and de se”, david lewis asks what happens to bayesian decision theory once we consider self-locating beliefs as well as de dicto beliefs. lewis’ answer: “very little. we replace the space of worlds by the space of centered worlds, or by the space of all inhabitants of worlds. all else is just as before.” i will argue that lewis is mistaken. i think there is a deep divide between our beliefs about the world and our beliefs about our place in the world. i will argue that changes in one’s purely self-locating beliefs should have no affect on one’s de dicto beliefs. moreover, i’ll argue that this division should be a consequence of the dynamics we adopt for de se beliefs. the dynamics i advocate are essentially identical to those proposed by halpern and tuttle ( ) and halpern ( ). (some minor differences between our approaches are described in the following footnote. ) so this paper can be seen as providing further reasons for adopting their account. lewis ( ), p. . unfortunately, the bulk of this work was done before i became aware that halpern and tuttle had already proposed essentially the same view. as a result, our presentations of this material differ in a number of ways. likewise, the terminology used in this paper is not the same as that used in halpern and tuttle ( ) and halpern ( ). regarding the dynamics of de se beliefs, the account laid out here differs from theirs in the following minor respects: . halpern and tuttle use ordered pairs of a world and time in place of the lewisian centered worlds used here (ordered triples of a world, time and individual). thus formulated, their work does not apply to non-temporal cases of self-location, such as my arguments for this conclusion will draw on the recent literature on the sleeping beauty problem. the sleeping beauty problem raises exactly the question of how changes in self-locating beliefs should affect our beliefs about the world. i’ll show that two of the responses to the sleeping beauty problem that have been advocated in the literature lead to highly counterintuitive consequences. in light of this, i’ll argue that we should adopt the account offered by halpern and tuttle. the paper will proceed as follows. in the next section i’ll present two competing dynamics for de se beliefs, the first employed by elga and lewis, the latter by halpern and tuttle. in the third and fourth sections i’ll discuss some preliminary material needed for the discussion ahead. in the third section i discuss some of the continuity issues that arise in de se contexts, and in the fourth section i discuss purely self-locating beliefs. in the fifth section i’ll present the sleeping beauty problem and sketch the three responses to it. in the sixth, seventh and eighth sections i’ll look at elga’s and lewis’ responses in detail, and show how they both lead to highly counterintuitive consequences. in the ninth section i’ll briefly look at some further considerations for and against these positions. i conclude in section ten. the big picture it’s standard to assume that belief is not an all or nothing affair, but rather admits of degrees. a subject’s beliefs are then represented by a credence function over the space of possibilities. the function assigns values between zero and one to regions of the space, representing the subject’s confidence that one of those possibilities obtains. the values it assigns are additive: the value it assigns to the union of several non-overlapping regions of the space is the sum of the values it assigns to each of these regions. the value it assigns to the entire space of possibilities is one, representing the subject’s certainty that some possibility obtains. in the case of de dicto beliefs, the space of possibilities is the space of possible worlds. can happen in cases of duplication, fission, etc. . in the dynamics i present in section two, a subject’s credences in doxastic alternatives are completely determined by her priors. the dynamics presented by halpern and tuttle are slightly less ambitious, and do not dictate a means by which one’s credence in a doxastic world should be divided among the doxastic alternatives at that world. the credence function takes worlds as arguments, and assigns to each world a degree of belief, or credence. the credence assigned to a proposition is the sum of the credences assigned to each world in that proposition. the worlds in which the subject has non-zero credences are the worlds she thinks might be hers, or her doxastic worlds. when we generalize to de se beliefs, the space of possibilities becomes the space of centered worlds. the credence function takes centered worlds as arguments, and assigns to each centered world a credence. the credence assigned to a centered proposition is the sum of the credences assigned to each centered world in that centered proposition. the centered worlds in which the subject has non-zero credences are the centered worlds she thinks might be hers, or her doxastic alternatives. return to de dicto beliefs. on a broadly bayesian picture, something like condi- tionalization will govern rational belief change. taking earman’s ( ) version of bayesianism as a model, we can characterize de dicto conditionalization as follows. a rational subject’s credences are fixed by her hypothetical priors and her total evidence. a subject’s credences are represented by a dynamic probability function, a function that changes with her evidence. a subject’s hypothetical priors are represented by a static probability function, a function that encodes her disposition to respond to evidence. (hypothetical priors are called ‘priors’ because they can be thought of as a rational subject’s original credences in possibilities, prior to the receipt of any evidence, and ‘hypothetical’ because it is unlikely that one ever was in such a state.) a piece of evidence is represented by a proposition, and a subject’s total evidence is represented by the conjunction of her evidential propositions. if a subject is rational, all belief changes will be the result of the addition of evidence. a rational subject’s credences can be determined from her priors and evidence di- rectly, but it’s convenient for our purposes to break this entailment into two steps. first, a rational subject’s total evidence and hypothetical priors determine her doxastic worlds: her doxastic worlds are the worlds she has non-zero priors in that are compatible with her evidence. second, a rational subject’s hypothetical priors and doxastic worlds de- termine her credences. her credences in non-doxastic worlds are, of course, zero. her for simplicitly i’m ignoring jeffery conditionalization and the like throughout this paper. credences in doxastic worlds are obtained by normalizing her hypothetical priors in these worlds. that is, by assigning credences to each doxastic world such that they sum to one, and such that the ratios between her credences in these worlds are the same as the ratios between her hypothetical priors in these worlds. we can see the effects of these constraints visually. picture a subject’s credence function as a three dimensional map, with each point on the plane representing a world, and the height at each point her credence in that world. there will be a boundary on this map outside of which everything is flat. this boundary outlines the set of doxastic worlds. since a subject’s belief in all possibilities sums to a constant, the volume inside the boundary is conserved. the relative height of the points inside the boundary is set by the subject’s priors—numbers written at each point. the actual height of these points is then fixed by the set of doxastic worlds—which points are inside the boundary—which determines how thinly the volume inside the boundary is spread. since priors are static, all belief changes are changes in the boundary. as the boundary shrinks, the points inside the boundary grow proportionally taller. (since all rational belief changes are the result of added evidence, the boundary can only shrink, not expand.) how should we generalize conditionalization to de se beliefs? one option is to replace every occurrence of ‘world’, ‘proposition’ and ‘doxastic world’ in the characterization of de dicto conditionalization just given with ‘centered world’, ‘centered proposition’ and ‘doxastic alternative’. seen visually, the picture will be just the same as before, except that each point on the map now represents a centered world instead of a world, and the boundary outlines the subject’s doxastic alternatives instead of her doxastic worlds. but frank arntzenius ( ) and chris hitchcock ( ) have shown that this ver- sion of de se conditionalization is untenable. say you’re looking at a clock you know to be accurate. the clock reads pm, so your current credence that it’s pm is , and your credence that it’s : pm is . a minute later the clock reads : pm, and your credence that it’s pm is , while your credence that it’s : pm is . this violates the requirement that all belief changes be the result of the addition of evidence. the addi- tion of evidence can only eliminate doxastic alternatives. but seeing the clock change did not just eliminate the doxastic alternatives where it’s pm, it also added doxastic alternatives at which it’s : pm. to accommodate these kinds of cases we need to allow a rational subject to both add and eliminate doxastic alternatives. (arntzenius ( ) gives us good reason to revise de dicto conditionalization in the same way, allowing a rational subject to both add and eliminate doxastic worlds. from now on i’ll use ‘de dicto conditionalization’ to refer to this appropriately modified version of conditional- ization. in section nine i’ll briefly need to speak of both the modified and unmodified versions; in that case i’ll call them ‘revised de dicto conditionalization’ and ‘unvrevised de dicto conditionalization’, respectively.) take the version of de se conditionalization just considered, and relax the requirement that all rational belief changes be the result of the addition of evidence. call this new version of de se conditionalization centered conditionalization. seen visually, the picture is the same as it was before, except that now the boundary can both expand and contract. centered conditionalization is one way to generalize de dicto conditionalization to de se beliefs. you can’t endorse both centered conditionalization and de dicto condi- tionalization, however, since their assignments conflict. to see this, consider a subject with just two doxastic worlds, a and b, with two doxastic alternatives at each world. assume that her credences are divided equally between alternatives, so that her cre- dence in each alternative is and her credence in each world is . now, what should her credences in a and b be if one of her alternatives at a is eliminated? according to de dicto conditionalization her credences in a and b should remain / . she has it’s well known that there are cases where it appears that conditionalization is violated, such as cases of brainwashing or memory loss. these cases are usually circumvented by labeling belief changes that result from cognitive defects or memory loss ‘irrational’. but arntzenius ( ) presents us with a case where this move isn’t available. in this case you flip a coin to see which of two routes you’ll take to shangri-la. if the coin comes up heads you’ll travel by the mountains, if it comes up tails you’ll travel by the sea. you further know that if you travel by the sea, then the guardians of shangri-la will erase your memories of the trip when you arrive, and replace them with memories of having traveled by the mountains. now say the coin comes up heads. while you’re traveling by the mountains your credence in heads is . when you arrive at shangri-la, however, it seems your credence in heads should become , a violation of conditionalization. and this is so despite that fact that you’ve suffered from no memory loss or cognitive defects. it is the counterfactual possibility that you would have suffered from a memory loss had the coin come up tails that compels you to revise your credences, and this doesn’t seem to provide grounds for the charge of irrationality. it follows from the additive nature of credences that a subject’s credence in a world is equal to the sum of her credences in the centered worlds at that world (and, likewise, that a subject’s prior in a world is equal to the sum of her priors in the centered worlds at that world). the same doxastic worlds, so de dicto conditionalization will assign the same credences. according to centered conditionalization, on the other hand, her credences in a and b should change. after the alternative at a is eliminated, centered conditionalization redistributes her credences among alternatives, so that her credence in each alternative is . since she has one alternative at a and two alternatives at b, her credence in a should now be and her credence in b should now be . there’s another way to generalize conditionalization to de se beliefs which doesn’t conflict with de dicto conditionalization. i’ll call it compartmentalized conditionalization. compartmentalized conditionalization is the same as centered conditionalization except that a different rule is used to determine a subject’s credences given her hypothetical priors and doxastic alternatives. on centered conditionalization, the subject’s priors in her doxastic alternatives are normalized. on compartmentalized conditionalization, the subject’s hypothetical priors in her doxastic worlds are normalized, and then the subject’s hypothetical priors in her doxastic alternatives are normalized at each doxastic world. that is, credences are assigned to each doxastic world such that they all sum to one, and such that the ratios between her credences in these worlds are the same as the ratios between her hypothetical priors in these worlds. credences are then assigned to the doxastic alternatives at a world such that they sum to the credence allocated to that world, and such that the ratios between her credences in these alternatives are the same as the ratios between her hypothetical priors in these alternatives. again we can imagine this visually on a three dimensional map, where every point on the plane is a centered world and the boundary outlines the doxastic alternatives. as with de dicto conditionalization and centered conditionalization, on compartmentalized conditionalization all belief changes are changes in the boundary. however, the same boundary change will bring about different belief changes on compartmentalized condi- tionalization than it will on centered conditionalization. these differences are especially easy to visualize if we assume a subject has a finite number of alternatives, with equal priors in each. in this special case the volume inside the boundary will behave like a body of water. on centered conditionlization, imagine the boundary as a wall surround- ing this body of water. as the boundary contracts, the water level rises, as the boundary expands, the water level falls. on compartmentalized conditionalization, imagine the boundary as a wall surrounding a body of water, but this time with a number of inner walls dividing the body into cells. as the boundary shrinks only the water level in cells that are being contracted rise; the water level in the other cells will be unaffected. the exception is during the last step of contraction when a cell is eliminated. in this case the water in the cell is squeezed out over the cell walls and funneled into the surviving cells. likewise, as the boundary grows, only the water level in cells that are expanding will fall; the water level in the other cells will be unaffected. the exception is when the boundary grows to the extent that a new cell is created, in which case water is funneled from all the other cells into it. i take david lewis, adam elga and most of the sleeping beauty literature to endorse centered conditionalization. joseph halpern, mark tuttle and i endorse compartmen- talized conditionalization. continuity the dynamics of de se beliefs raises questions about belief continuity which don’t arise in de dicto contexts. consider again the case presented in the last section, where a subject is watching a clock they know to be accurate. when the clock changes from pm to : pm, the subject discards all of her alternatives at which it’s pm and replaces them with alternatives at which it’s : pm. intuitively, her credences in these new alternatives should bear some relation to what her credences were in the alternatives they’ve just replaced. but nothing we’ve said so far requires that this be the case. suppose, for example, that the subject watching the clock has only two doxastic worlds, a and b, and that she has only one doxastic alternative at each world. further suppose that she updates her beliefs using centered conditionalization and that at pm her priors in her two alternatives (a pm and b pm) are equal, so her credences in a pm and b pm are / . when she sees the clock register : pm, what should her credences in a : pm and b : pm be? prima facie, we have no reason to think they’ll be / . her priors in a pm and b pm were equal, but it’s now : pm and these are no longer her to make this easy to visualize i’ve implicitly assumed that there’s a single continuous boundary; i.e., assumed that the boundaries won’t contract or expand in a way that forms islands. alternatives. her alternatives are now a : pm and b : pm, and there’s no reason that her priors in these alternatives should be equal. for subjects like us, who have a sense of time passing, every belief change will include a time changing component. as we notice time pass, we replace our old alternatives with new ones located at a later time. since every change brings an awareness that time has passed, every belief change involves the replacement of old alternatives with new ones. prima facie, there’s no reason to think that the beliefs of such subjects should be in any way constant—that their credences shouldn’t be constantly ricochetting around simply due to the passage of time—without imposing a further constraint on their credences. what we need is a continuity principle, a principle that, in the appropriate circum- stances, forces a subject’s credences in new alternatives to be appropriately continuous with her credences in old alternatives. for subjects like us, virtually every diachronic argument with regards to what one’s credences should be (including several that we’ll look at in this paper) will require a principle of this kind to go through. to cash out such a principle we need to answer two questions. first, what is it for a subject’s credences in old and new alternatives to be ‘appropriately continuous’ ? second, what are the ‘appropriate circumstances’ in which a subject’s credences in old and new alternatives should be continuous? let’s start with the first question. restrict our attention to the cases where the issue of continuity arises: belief changes where, at a given doxastic world, some old doxastic alternatives are eliminated and some new ones added. say that an old and new alternative are continuous if a subject’s credences in the old and new alternative should be ‘appropriately continuous’. the easiest case to consider is a belief change which just replaces one doxastic alter- native at a world with another. if the new alternative is continuous with the old one, then it seems the subject should have the same credence in the new alternative as she had in the old alternative. what about a belief change which just eliminates one alternative at a world and replaces it with two? assume one of these new alternatives is continuous with the old this doxastic behavior also holds for some subjects who don’t have a sense of time passing. an awareness of change and the knowledge that change requires the passage of time are sufficient. one. it doesn’t seem that the subject’s credence in the new continuous alternative should need to be the same as her credence was in the old one. after all, her new epistemic situation is importantly different from her old one; she now has more alternatives at this world than she did before. i suggest that the intuitive relation between the subject’s credences in the old and new continuous alternatives is the following: her credences should be such that if there was now a second belief change that just eliminated the other new alternative, then the subject’s credence in the new continuous alternative should be the same as what her credence was in the old alternative. what about a belief change which just removes two alternatives at a world and re- places it with one? assume the new alternative is continuous with one of the old ones. again, it doesn’t seem that the subject’s credence in the new alternative should need to be the same as her credence was in the old continuous alternative. after all, her new epistemic situation is importantly different from her old one; she now has fewer alter- natives at this world than she did before. i suggest that the intuitive relation between the subject’s credences in the old and new continuous alternatives is the following: the subject’s credences should be such that if there was now a second belief change that just reintroduced the other old alternative, then the subject’s credence in the new alternative should now be the same as her what credence was in the old continuous alternative. more generally, the intuitive idea behind these cases is that if one alternative is continuous with another, it should be the case that in otherwise identical epistemic sit- uations they should be alloted the same credence. using this idea, we can provide a general characterization of what it is for a subject’s credences in old and new alterna- tives to be continuous. namely, if a belief change has a new alternative replace an old alternative, and the two alternatives are continuous, then a subject’s credences should be such that if a second belief change reverted the subject’s epistemic state back to how it was, with the exception of the new alternative taking the place of the old one, then her credence in the new alternative should be the same as what her credence was in the old one. this characterization of continuity can be more simply captured if we assume cen- tered conditionalization. on centered conditionalization, a sufficient and almost neces- sary condition for two alternatives to be continuous is that they have the same priors. (the sole exception to this as a necessary condition is the trivial case in which a subject has only one doxastic alternative and has it replaced by another. in this case the old and new alternatives will be continuous regardless of her priors in them, since her credence in each alternative will trivially be .) so on centered conditionalization we can essentially think of continuous alternatives as alternatives with the same priors. for compartmen- talized conditionalization this is not the case. while a pair of alternatives with the same priors will always be continuous, it will often be the case that two continuous alterna- tives will not have the same priors. (we’ll return to the topic of compartmentalized conditionalization and continuity in section nine.) let’s turn to the second question: what are the ‘appropriate circumstances’ in which a subject’s credences in old and new alternatives should be continuous? i.e., when should an old and new alternative be continuous? this is a difficult question to answer. intuitively, alternatives should be continuous when they’re similar or related in the ap- propriate way. but it’s hard to spell out what the right criteria are. i won’t take a position here on what these standards should be. instead, i’ll take a continuity prin- ciple to be any principle which constraints rational credences such that some particular standard of continuity is preserved. in the rest of this paper i’ll assume that the subjects in question are like us, and have a sense of time passing. as a result, several of the arguments we’ll look at in this paper will require a continuity principle of some kind to go through. in these places, i’ll point out what standards of continuity are required. i won’t take a position on whether these versions of the continuity principle are correct. given that subjects have a sense of time passing, it will often be convenient to leave the temporal shifting of alternatives implicit when describing belief changes, and to only explicitly mention the addition or elimination of alternatives not due to the passage of time. so, for example, consider a subject with two doxastic alternatives, one at which a coin toss comes up heads, the other at which the coin comes up tails. suppose she learns the that the coin came up heads. if we leave temporal shifts implicit, we describe this belief change as eliminating her tails alternative. if we make temporal shifts explicit, we describe this belief change as eliminating both of her old alternatives, and adding a new tails alternative located at a later time. leaving temporal shifting implicit allows us to focus on the salient features of cases in which the passage of time is not the central issue, and allows us to concisely present cases where the temporal shifting of alternatives is straightforward. purely self-locating belief changes i’ve claimed that changes in purely self-locating beliefs shouldn’t affect our beliefs about what the world is like. now i need to spell out what purely self-locating belief changes are. in some cases it’s uncontentious that changes in our self-locating beliefs do affect our de dicto beliefs. consider a case where there appear to be two clocks in front of you. the one on the left reads pm, and the one on the right reads pm. you know that one of the clocks is in fact a ceramic sculpture that looks like a clock, while the other is a working clock that has been set to the right time. you don’t what time it is, nor which clock is the sculpture. now, if your self-locating beliefs were to change so that you believed it was pm, you would change your beliefs about what the world is like: you would believe that in your world the clock on the right was a ceramic sculpture. likewise, if you came to believe that in your world the clock on the right was a ceramic sculpture, you would come to believe it was pm. in cases like these self-locating beliefs are tied to de dicto beliefs. we want to separate cases like these from the cases that are contentious—cases in which i’ll claim that self-locating belief changes shouldn’t affect our de dicto beliefs. a change in purely self-locating beliefs is a belief change which results in the addition or elimination of doxastic alternatives, but which doesn’t result in the addition or elim- ination of doxastic worlds. so take the case of the two sages, where each is uncertain of who they are. if they come to believe that they are zorn or xingu, then they’ve eliminated the doxastic alternative where they are xingu or zorn. their doxastic worlds are the same, though; they still believe they’re in the world they’re in. so this is a case of purely self-locating change. contrast purely self-locating belief changes with purely world-locating belief changes. a purely world-locating change is a belief change which adds or eliminates doxastic worlds but does not otherwise affect the subject’s doxastic alternatives. examples of purely world-locating changes are hard to come by for subjects with a sense of time passing. since for such subjects every belief change involves the replacement of old alternatives with new ones, virtually no belief change is purely world-locating. every belief change can be uniquely decomposed into a purely world-locating part and a purely self-locating part. the addition and elimination of doxastic alternatives at worlds that are added or eliminated is the purely world locating part of the belief change, and the addition or elimination of doxastic alternatives at worlds that aren’t added or eliminated is the purely self-locating part of the belief change. for convenience, let ‘purely self-locating change’ apply both to belief changes that are purely self-locating and to the purely self-locating parts of belief changes. likewise, let ‘purely world-locating change’ apply both to belief changes that are purely world-locating and to the purely world-locating parts of belief changes. my claim is that in cases of purely self-locating change, one’s credences in worlds, and thus in propositions, shouldn’t change. this follows from de dicto conditionalization, and thus from compartmentalized conditionalization. on de dicto conditionalization a subject’s credence in worlds is fixed by her doxastic worlds and her priors. purely self- locating changes don’t change a subject’s doxastic worlds, and her priors are static. so purely self-locating changes won’t affect one’s credences in worlds. for subjects like us, most purely self-locating changes are the boring purely self- locating changes brought about by our awareness of time passing. as we notice time pass we shift our alternatives, replacing each old alternative with a new one centered on the same individual but a later time. exotic purely self-locating changes, where there are changes in the number of alternatives at a world, are rare. many cases which seem to be exotic purely self-locating changes aren’t purely self-locating changes at all. as i’m writing this, i’m wondering what time it is. when i last looked at the clock it was pm. two of the times i think it might be are pm and : pm. it might seem that looking at a clock and seeing that it’s pm is an exotic purely self-locating change, a change which eliminates the alternatives at my doxastic worlds which are located at the wrong time, but which leaves my doxastic worlds unchanged. but there is a fact about the temporal distance between when i last looked at the clock and when i typed the sentence “as i’m writing this, i’m wondering what time it is.” the doxastic alternatives where it’s pm are at doxastic worlds where an hour has passed between these two events, while the doxastic alternatives where it’s : pm are at doxastic worlds where minutes have passed between these two events. so looking at the clock and finding out that it’s pm isn’t an exotic purely self-locating change; time shifts aside, it’s a purely world-locating change. we can see how little of our belief change is due to exotic purely self-locating changes in another way. your doxastic alternatives are the centered worlds that you think might be yours. assume transparency—that subjects always have access to their own subjec- tive states. then for you to think that a centered world is yours, it must be subjectively indistinguishable from your current subjective state. so all of the centered worlds you think might be yours—your doxastic alternatives—must be subjectively indistinguish- able. for exotic purely self-locating change, one needs to increase or decrease the number of doxastic alternatives at a doxastic world. so there can only be cases of exotic purely self-locating change when there are doxastic worlds in which we have multiple doxastic alternatives, or in cases where we end up with multiple doxastic alternatives at a dox- astic world. but doxastic worlds with multiple doxastic alternatives are strange worlds. they are worlds in which there are individuals-at-a-time that are in states subjectively a related case is given by arntzenius ( ). a prisoner is put in a cell with two clocks, one that reads pm and one that reads pm. she knows that one of them is accurate, but not which, and her credences are evenly split between them. she further knows that her jailers will a flip a coin at midnight, and if it comes up heads, they’ll turn off the lights. arntzenius argues that if the lights are still on five hours from now, the prisoner’s credences in head/tails should be / . what should the prisoner’s credences be on centered and compartmentalized conditionalization? her credences are now evenly split between four sets of worlds: ( ) worlds where the coin will be flipped six hours after she was put in the cell and the coin will come up heads, ( ) worlds where the coin will be flipped five hours after she was put in the cell and the coin will come up heads, ( ) worlds where the coin will be flipped six hours after she was put in the cell and the coin will come up tails, and ( ) worlds where the coin will be flipped five hours after she was put in the cell and the coin will come up tails. if the lights are still on five hours from now, she’ll eliminate the set of worlds where the coin will be flipped five hours after she was put in the cell and the coin came up heads. this is a purely world-locating change, not a purely self-locating change, so centered and compartmentalized conditionalization will treat it the same way: her credence in each of the remaining sets of worlds will increase to , so her credence in heads/tails will be / . indistinguishable from other individuals-at-a-time. consider my life as a sequence of time-slices. ignore times when i’ve been uncon- scious or otherwise incapable of rational thought, and consider slices that are far enough apart to be noticeably distinct. how many of these me-slices are in subjectively indis- tinguishable states? if i’m in the set of worlds i think i’m probably in, none of them are. likewise, if the world is like i think it probably is, no me-slice will be in a state indistinguishable from that of any time slice of anyone else, present, future or past. at the worlds i think are likely, exotic purely self-locating changes don’t arise. only at rare fringe worlds are there exotic purely self-locating changes, and my credence in these worlds is so small that these changes have little affect on my overall belief distribution. sleeping beauty we saw a case of exotic purely self-locating change above, with the two sages. if the two sages come to believe that they’re zorn, they’ve gone from having two doxastic alternatives at their world to one. a more interesting case of exotic purely self-locating change is the sleeping beauty case: the sleeping beauty case: some researchers are going to put you to sleep for several days. they will put you to sleep on sunday night, and then flip a coin. if the coin comes up heads, they will wake you up once during that time; if it comes up tails, they will wake you up twice. if heads comes up they will wake you up on monday morning. if tails comes up they will wake you up on monday morning and tuesday morning, and in-between monday and tuesday, while your are sleeping, they will erase the memories of your awakening. when you wake up, what should your credence be that the coin came up heads? if you then learn that it’s monday, what should your credence in heads become? on sunday you have credence that you’re in a world where the coin will come up heads, and a credence that you’re in a world where the coin will come up tails. assume that on sunday you have one doxastic alternative at each of these doxastic worlds. when you wake up this is no longer the case. at each of the tails worlds you now have two doxastic alternatives—one where it’s monday and one where it’s tuesday. this is a purely self-locating change, so on compartmentalized conditionalization your credence in the proposition that heads came up should remain . likewise for tails. given tails, what should your credence be that it’s monday versus tuesday? your credence in the tails worlds is , so your credences in these two alternatives must sum to . by compartmentalized conditionalization, the should be divided such that the ratio between the two alternatives is the same as the ratio between your hypothetical priors in these alternatives. those swayed by indifference principles will advocate assigning equal credences to these two alternatives. indifference principles can be seen as rationality constraints on one’s priors. an indifference principle requires that one’s priors be such that whenever one is ‘indifferent’ between several possibilities (by some standard of indifference), one’s credences in these possibilities are equal. i generally don’t find indifference principles very compelling, but they’re a convenient way to generate examples of permissible belief distributions. so for convenience i’ll use something like an indifference principle as a heuristic by which to assign specific values. so on the account i favor, when you wake up your credences in heads and tails should be / , with your credence in tails split evenly between monday and tuesday. how should your credences change if you then learn that it’s monday? this information eliminates a doxastic alternative at the tails worlds, the alternative where it’s tuesday. this is another purely self-locating change, so your credences in heads and tails should remain / . two other responses to the sleeping beauty problem have been advocated in the literature. the majority of the literature on sleeping beauty has endorsed the response offered by adam elga ( ). elga proposes that upon awaking we should have a credence in heads and a credence in tails, the latter split evenly between monday and tuesday. if you then learn that it’s monday, you conditionalize and regain your original / credences in heads and tails. see dorr ( ), monton ( ), arntzenius ( ), and hitchcock ( ). the other response is lewis’ ( ). lewis proposes that we retain our / credences in heads and tails when we wake up, with our credence in tails split evenly between monday and tuesday. lewis’ account diverges from the account i favor in what happens when you then learn that it’s monday. lewis holds that you should conditionalize and come to have a credence in heads and a credence in tails. we can see the disagreements between the account i favor and their accounts in terms of how we think changes in purely self-locating beliefs affect our de dicto beliefs. on the account i favor, our de dicto beliefs are held fixed in all cases of purely self- locating change. so neither waking up in the sleeping beauty case nor then being told it’s monday changes your credences in heads and tails. on lewis’ account increasing the number of doxastic alternatives at a world doesn’t alter our de dicto beliefs, but decreasing the number of doxastic alternatives does; namely, decreasing the number of doxastic alternatives at a world decreases our cre- dence in that world. so waking up in the sleeping beauty case doesn’t change our credences, but then being told it’s monday does, decreasing our credence in tails. on elga’s account both kinds of purely self-locating changes affect our de dicto beliefs. increasing the number of doxastic alternatives at a world increases our credence in that world, and decreasing the number of doxastic alternatives at a world decreases our credence in that world. so waking up in the sleeping beauty case increases our credence in tails, and then being told it’s monday decreases our credence in tails. we can also see the differences between these accounts in terms of which generaliza- tion of conditionalization one endorses with regards to de se beliefs. the response to the sleeping beauty case i’ve offered above follows straightforwardly from compartmen- talized conditionalization and some minimal assumptions about priors. we’ll see that elga’s and lewis’ responses rely on centered conditionalization. in the next section i’ll analyze an argument for elga’s response, and show that elga’s response leads to some highly counterintuitive results. (a different kind of argument for elga’s response using dutch books doesn’t neatly intersect with the issues i look at here. as it turns out, dutch books do little to settle the issue between centered and compart- mentalized conditionalization. since these issues are given a satisfactory treatment in halpern ( ), i’ll restrict my comments on them to the following footnote. ) i’ll then look at lewis’ position. i’ll show that while lewis’ account escapes the difficulties facing elga’s response, it ends up facing other, equally serious, difficulties. a caveat: i present elga’s and lewis’ arguments in my own terms. in some places i’ve filled in and spelled out implicit premises that the arguments require. i believe the arguments i present are faithful to the original arguments, but it matters little for my purposes if they’re not. the arguments i do present will lead us to interesting results all the same. elga’s response to sleeping beauty the sleeping beauty case is an instance of a general type of case. the same questions arise for cases involving duplication or fission. consider a case where instead of waking you up twice if the coin comes up tails, the researchers create a duplicate of you in a distant, qualitatively identical location. on sunday your credences in heads and tails are / . what should your credences in heads and tails be when you wake up on monday? given tails, what should your credence be that you’re the duplicate? i’ll take it that the answers given for the sleeping beauty case apply here as well. this needn’t be the case, of course. one might try to treat sleeping beauty-type cases differently from duplications cases, duplication cases differently from fission cases, and so on. but for the purposes the cleanest presentation of a dutch book argument for elga’s response is given in hitchcock ( ). hitchcock argues that the salient dutch book in the sleeping beauty case is one in which we should adopt : odds on tails. the proponent of compartmentalized conditionalization will agree that in the dutch book hitchcock describes, one should accept : odds on tails as fair. but she will disagree that this suggests her credences should be / . this is because she will consider it to be a case of double counting—tails payoffs are enacted twice, while heads payoffs are enacted only once—so someone with equal credences in h/t should accept : odds. what the dutch book suggets, she will argue, is that her credences in h/t should be / . after all, if she had / credences in h/t, and tails payoffs are counted twice, she should be accepting : odds, not the : odds the dutch book suggests. the fallout, i think, is that dutch books do little to settle the issue between centered and compart- mentalized conditionalization. while both positions will generally agree on how one should bet, they will disagree on what implications this has with regards to one’s credences. these issues are addressed in halpern ( ). the response to the dutch book argument given above first appears in arntze- nius ( ), along with some interesting thoughts about the relation between these issues and decision theory. of this paper, i’ll assume that they should be treated the same way. elga’s argument for his response follows from four principles: . an indifference principle . a continuity principle . centered conditionalization . the principal principle let d(·) be your credence function, h/t be the propositions that the coin came up heads/tails, and mon/tue the propositions that it is monday/tuesday. the first step of elga’s argument uses an indifference principle to argue that upon awakening d(t∧mon) = d(t∧tue). the second step of the argument uses a continuity prin- ciple, the principal principle and centered conditionalization to argue that upon awak- ening d(h∧mon) = d(t∧mon). from these two steps it follows that d(h∧mon) = d(t∧mon) = d(t∧tue) = . the third step of the argument uses the continuity principle and centered conditionalization to argue that if you learn it’s monday after awaking, then d(h∧mon) = d(t∧mon) = . the first step of the argument uses a restricted version of the indifference principle, proposed and defended by elga ( ). according to elga’s principle you should have the same credences in subjectively identical doxastic alternatives at the same doxastic world. since i’m assuming transparency—that subjects always have access to their own subjective states—a subject’s doxastic alternatives are always subjectively identical, and satisfying this principle entails having the same credences in all doxastic alternatives at the same doxastic world. after you wake up in the sleeping beauty case you have two doxastic alternatives at each tails world: t∧mon and t∧tue. by this principle d(t∧mon) = d(t∧tue). the second and third steps of the argument use a continuity principle. as we’ve seen, the content of such a principle depends on the standards of continuity employed. for elga’s argument, any continuity principle for which the following is a sufficient condition for continuity will do. consider a belief change which eliminates some old alternatives at a world and replaces them with new ones. an old alternative and new alternative should be continuous if: (a) both alternatives are focused on the same person p, (b) of the new alternatives focused on p, this new alternative is the located at the earliest time following the time of the old alternative. now consider the belief change that takes place between going to sleep on sunday and waking up on monday in the sleeping beauty case. assume our belief changes are governed by centered conditionalization, and that the purely world-locating part of this change, if any, won’t affect our credences in heads and tails. (for conciseness, i’ll leave the role that centered conditionalization plays in this argument—connecting up our credences and priors—implicit.) by the principle principal, our original credences in h∧sun and t∧sun are / , and thus our priors in h∧sun and t∧sun are equal. from the continuity principle it follows that h∧sun and t∧sun are continuous with h∧mon and t∧mon, respectively, and thus that our priors in h∧sun and t∧sun are the same as our priors in h∧mon and t∧mon. so our priors in h∧mon and t∧mon are equal, and thus so are our credences. so the continuity principle, centered conditionalization and the principal principle entail that d(h∧mon) = d(t∧mon), and the restricted indifference principle entails that d(t∧mon) = d(t∧tue). combining these results, it follows that upon awaking in the sleeping beauty case one’s credences should be d(h∧mon) = d(t∧mon) = d(t∧tue) = . say you’re woken up at am. what if at : am you learn that it’s monday? take the belief change between and : am, and assume that the purely world- locating part of this change won’t change our credences in heads and tails. from the continuity principle it follows that h∧mon( am) and t∧mon( am) are continuous with h∧mon( : am) and t∧mon( : am), respectively, and thus that our priors in h∧mon( am) and t∧mon( am) are the same as our priors in h∧mon( : am) and t∧mon( : am). we saw above that our priors in h∧mon( am) and t∧mon( am) are equal, so our priors in h∧mon( : am) and t∧mon( : am) must be equal as well. so our credences after being told it’s monday should be d(h∧mon( : am)) = d(t∧mon( : am)) = . note that the principal principle only plays a superficial role in elga’s argument. the principal principle sets our credences in heads and tails on sunday to / . but the argument goes through equally well given any reason for / credences in heads and tails on sunday. likewise, the argument goes through just as well if heads and tails are replaced by two different hypotheses we have other reasons for having / credences in. in the sleeping beauty case it’s uncontentious that the principal principle applies on sunday, and thus that you should have / credences in heads and tails. some of the sleeping beauty literature has focused on whether the principal principle should also apply after you wake up on monday. the question is whether you get admissible evidence when you wake up on monday. if so, the thought goes, then the principal principle should still apply, and your credences in heads and tails should remain / . it follows from elga’s argument that upon awaking our credences in heads and tails should be / . so if elga’s argument is sound, you do get inadmissible evidence when you wake up on monday. but i think debating admissibility and the principal principle is the wrong way to approach the problem. first, there is no agreement as to what counts as admissible evidence. this makes it hard to make progress in a debate over whether someone’s evidence is admissible. second, focusing on the issue of whether the principal principle applies on monday gets us relatively little. as we just saw, the argument goes through just as well if heads and tails are replaced by two different hypotheses we have other reasons for having / credences in. concluding one thing or another about the principal principle doesn’t tell us what to say in these other cases. finally, if we conclude that we don’t receive inadmissible evidence upon awaking we still need to decide what to say about elga’s argument, since the argument entails the / result without making any assumptions about the admissibility of your evidence on monday. (the argument only requires that the principal principle hold on sunday, before you wake up.) given this, i think it’s better to assess the merits of elga’s argument and then see what implications this has regarding admissibility, than to use admissibility to assess the merits of elga’s argument. if one accepts elga’s argument, then purely self-locating changes that increase the number of doxastic alternatives at a world will increase one’s credence in that world relative to worlds without such an increase. likewise, one’s credence in a proposition see lewis ( ) and dorr ( ). which multiplies doxastic alternatives will increase relative to propositions that don’t multiply alternatives. one can see why this should be so for the proponent of elga’s response: to endorse elga’s response is to think that one’s credence in tails should increase relative to one’s credence in heads when the number of alternatives given tails increases (and the number of alternatives given heads does not). however, accepting elga’s argument leaves one open to the following objection, based on an argument pointed out to me by tim maudlin: the many brains argument: consider the hypothesis that you’re a brain in a vat. i take it that this is epistemically possible and (perhaps) nomologically possible. your current credence in this possibility, however, is presumably very low. now consider the proposition that you’re in a world where brains in vats are constantly being constructed in states subjectively indistinguishable from your own. let your credence in this proposition be < p < , and your credence that there will be no multiplication of doxastic alternatives be −p. if you accept elga’s argument then your credence in this hypothesis should be constantly increasing and will converge to one. thus, if you hold such a position you should come to believe (if not yet, then in a little while) that these brains in vats are being created. it follows from elga’s indifference principle that your credences should be spread evenly among the doxastic alternatives at a world. so as you become certain that these brains in vats are being created, you should become certain that you’re a brain in the vat. the many brains argument assumed that brain in the vat duplication is the only proposition you have a non-zero credence in that multiplies doxastic alternatives. now suppose that you also have a small credence in the proposition that you’re in a world where duplicates of you are constantly being created on distant but qualitatively identical worlds. then you’ll come to believe (if not yet, then in a little while) that these brains in the vats are being created or that these duplicates of you are being created. likewise, you’ll come to believe that you are a brain in a vat or a duplicate on a distant world. by a similar process, you can generalize the result of the many brains argument to any number of propositions that multiply alternatives. in general, if you accept elga’s argument then you will come to believe that you’re in a world where you have many doxastic alternatives. in section four i argued that worlds with multiple doxastic alternatives are strange worlds. so if we accept elga’s argument, we’ll come to believe (if not yet, then in a little while) that we live in a strange world. this is an unwelcome consequence. an escape route? to escape these many brains-type arguments we need to reject elga’s argument. elga’s argument relied on four principles: the principal principle, an indifference principle, a continuity principle and centered conditionalization. what if we reject the principal principle? we saw above that the principal principle only plays a superficial role in the elga’s argument; any means of assigning / credences to heads/tails will do. in the many brains-type arguments the principal principle plays no role at all; these arguments go through given any assignment of non-zero credences to the relevant propositions. well, what if we do assign a credence to the relevant propositions, those that multiply our doxastic alternatives? that is, what if we have priors in any world that multiplies our doxastic alternatives? it will still be true that purely self-locating changes that increase the number of doxastic alternatives at a world will increase one’s credence in that world, but it will be true trivially, since there will be no purely self- locating changes which increase the number of doxastic alternatives at a world. any world where this might have happened gets a prior. this is counterintuitive, since we can imagine cases where it seems we have very good evidence that we’re in a world where our doxastic alternatives are being multiplied. consider a scientist who has invented brain-in-the-vat duplication technology (though she’s never tried this on herself), and who has just turned on a machine that creates brains in states subjectively identical to her own. on this approach, such a scientist should have a credence in the machine working and successfully creating epistemic duplicates of herself, even if she has no reason to think anything will interfere and the same purpose could be achieved by assigning an infinitesimal credence to such worlds, as long as worlds like our own were still assigned finite credences. assigning infinitesimal credences raises the same problems as assigning credences. believes the machine to be in perfect working order! i don’t think this response to the sleeping beauty case is very satisfying. in any case, my priors in worlds that multiply alternatives aren’t all , i don’t accept the conclusion of the many brains-type arguments, and i don’t feel particularly irrational (in this regard). so i’m inclined to look for a different solution. what if we reject elga’s indifference principle? as with the principal principle, simply rejecting the indifference principle isn’t enough to escape the many brains-type arguments. what is needed is for the sum of our credences in the alternatives at an alternative multiplying world to converge to a value less than one. given the continuity principle and centered conditionalization, new alternatives will get the same priors as the alternatives they’re continuous with. so we can’t play with the priors assigned to continuous alternatives. to get the sum of our credences in the alternatives at alternative multiplying worlds to converge to less than one, we need to restrict the priors assigned to discontinuous alternatives. the simplest way to do this is to have a prior in every centered world that would otherwise become a discontinuous alternative. a less extreme option is to have priors such that finite but decreasing credences are assigned to new discontinuous alternatives, such that the sum of our credences in the alternatives at that world converge to some value less than one. i said earlier that i generally don’t find indifference principles very compelling as a constraint on rational priors. at the same time, it’s plausible that we often do have roughly equal credences in possibilities we’re in some sense indifferent between, such as doxastic alternatives at the same world. i also think that most of us think we don’t live in a strange world, and aren’t irrational in thinking this. if i’m right, then it’s not plausible to insist that having an ‘indifferent’ distribution commits us to thinking we live in a strange world, and we should look for a different way to avoid the many brains-type arguments. we’re left with two ways to escape the many brains-type arguments: we can deny elga’s continuity principle or we can deny centered conditionalization. it’s not surpris- ing that these are the two remaining options. the source of the difficulty is that if one accepts elga’s argument, purely self-locating changes that increase the number of dox- astic alternatives at a world will increase one’s credence in that world (relative to worlds without such an increase). but the continuity principle and centered conditionalization alone entail this. consider two doxastic worlds, a and b. at t we have n alternatives at each world. at t a purely self-locating change adds m alternatives to a. by the continuity principle and centered conditionalization, our priors in n of the alternatives at each world at t will be the same as our priors in their predecessors. but world a gets m additional alternatives with non-zero priors. so our credence in a will increase relative to our credence in b. given the continuity principle and centered conditionalization, some further auxil- iary assumptions—that one has non-zero credences in alternative multiplying hypothe- ses, etc.—are still needed to get the many brains-type arguments to work. but the continuity principle and centered conditionalization are the crucial elements. a plausi- ble response to the many brains-type arguments is going to need to reject one of them. lewis’ response to sleeping beauty lewis’ discussion of the sleeping beauty case questions elga’s response by looking at the principal principle and at whether any inadmissible evidence is received upon awaking. lewis contends that no evidence is received, and thus that the principal principle should still apply. i’ve said above why i think this is the wrong way to approach the problem. and as we saw, even if lewis is right, there remains the task of deciding what’s wrong with elga’s argument. so how would lewis address elga’s argument? lewis accepts a principal principle that entails that our credences in heads and tails on sunday should be / . furthermore, lewis explicitly endorses (centered) conditionalization and the indifference principle. so he must reject elga’s continuity principle. lewis’ argument requries a somewhat different continuity principle, one compatible with the following two conditions. first, an old alternative and new alternative at a world should be continuous if: (a) both alternatives are focused on the same person p, (b) of the new alternatives focused on p, this new alternative is the located at the earliest time following the time of the old alternative, (c) the belief change hasn’t increased the number of alternatives at that world. second, an old alternative and new alternative should never be continuous if both (a) and (b) hold and the belief change has increased the number of alternatives at that world. so how are credences assigned in cases where the number of alternatives at a world increases? lewis’ position seems to be that in cases of purely self-locating change where the number of alternatives increases at a world, we get no evidence with regards to what world we’re in. call this the increasing no-evidence principle: in cases of purely self-locating change where the number of alternatives at a world increases, our credence in that world should remain the same. so lewis’ argument for his response uses five principles: . an indifference principle . a continuity principle . centered conditionalization . the principal principle . the increasing no-evidence principle by the principal principle our credences in heads and tails on sunday should be / . as before, assume that the purely world-locating part of the belief change between sunday and monday (if any) won’t affect our credences in heads and tails. the purely self- locating part of this change increases the number of alternatives at tails worlds, so by the increasing no-evidence principle our credence in tails should remain the same on monday as it was on sunday: . so our credence in heads on monday should be as well. by the indifference principle, our credences in t∧mon and t∧tue should be the same, so d(t∧mon) = d(t∧tue) = and d(h∧mon) = . what if you then learn at : am that it’s monday? the reasoning here is the same as before. take the belief change between and : am, and assume that the purely world-locating part of this change won’t change our credences in heads and tails. by the continuity principle and centered conditionalization, our priors in h∧mon( am) and t∧mon( am) should be the same as our priors in h∧mon( : am) and t∧mon( : am), respectively. our prior in h∧mon( am) is twice that of our prior in t∧mon( am), so our prior in h∧mon( : am) should be twice that of our prior in t∧mon( : am). so our credences after being told it’s monday should then be d(h∧mon( : am)) = , d(t∧mon( : am)) = . elga’s argument ran into problems because it entailed that purely self-locating changes that increased the number of alternatives at a world increased one’s credences in that world, relative to worlds without such an increase. lewis avoids this result by rejecting elga’s continuity principle and adopting the increasing no-evidence principle. how- ever, if one accepts either elga or lewis’ argument, then purely self-locating changes that decrease the number of doxastic alternatives at a world will decrease one’s credence in that world, relative to worlds without such a decrease. and this also leads to coun- terintuitive consequences. namely, accepting lewis’ argument leaves one open to the following objection: the sadistic scientists argument: consider the hypothesis that you’re in a world where every second some scientists will create n brains in vats in situations sub- jectively identical to your own. a half second after the brains are created, the scientists will destroy them. let your credence in this proposition be < p < , and your credence that there will be no creation or destruction of doxastic alter- natives be −p. when the brains are created your credence that you are in such a world will remain the same (increasing no-evidence principle), and this credence will be evenly split between your n + alternatives (indifference principle). as a half second second passes and these brains are destroyed, your credence that you are in such a world will decrease by the appropriate amount (lewis’ continuity principle and centered conditionalization). so as each second passes, your cre- dence that you are in such a world will decrease. thus, if you hold lewis’ position you should come to believe (if not yet, then in a little while) that these brains in vats are not being created. the sadistic scientists argument assumed that brain in vat destruction is the only proposition you have a non-zero credence in that diminishes alternatives. now suppose that you also had a small credence in the proposition that duplicates of you on distant but qualitatively identical worlds were being created and destroyed. then you’d come to believe (if not yet, then in a little while) that neither of these propositions was true. the result generalizes to any number of propositions that diminish alternatives. in general, if you accept lewis’ argument then you’ll come to believe that you’re not in a world where continual doxastic elimination is taking place. i take this result to be counterintuitive. if the result as stated does not move you, imagine a case in which you are living in a world where brain-in-the-vat creation tech- nology is cheap and easily accessible. an enemy of yours who would enjoy destroying brains in vats in your subjective state tells you that at midnight she’ll spend an hour creating n such brains, and at am she’ll spend an hour destroying them. this enemy has the resources to carry out this threat, and reliably carries out the threats she makes. if n is big enough, and you uphold the account i am attributing to lewis, then though you’re now almost certain that she will carry out her threat, you’ll be almost certain that she didn’t when you wake up tomorrow morning. indeed, if n is big enough, you could even go with her and watch as she creates the brains and destroys them; if you watch for long enough you won’t believe your eyes! the difficulty stems from the fact that purely self-locating changes that decrease the number of alternatives at a world decrease one’s credence in that world (relative to worlds without such a decrease). this follows directly from centered conditionalization and either lewis’ or elga’s continuity principles. take two doxastic worlds, a and b. at t we have n alternatives at each world. at t a purely self-locating change eliminates m of the alternatives at a (where m < n). by centered conditionalization and either continuity principle, our priors in n of the alternatives at a and n−m of the alternatives at b at t will be the same as our priors in their predecessors. but world a loses m alternatives, so our credence in a will decrease relative to our credence in b. as with the many brains-type arguments, several further assumptions are needed for the sadistic scientists-type arguments to go through. but the continuity principle and centered conditionalization are the crucial elements. we saw that a plausible rejection of the many brains-type arguments required that we reject either centered conditionaliza- tion or elga’s continuity principle. to escape the sadistic scientists-type arguments as well our choices are further restricted: we must reject either centered conditionalization or both elga’s and lewis’ continuity principles. further considerations i’ve presented three positions on the dynamics of de se beliefs: elga’s stance, lewis’ stance, and the stance of halpern, tuttle and i. in the previous three sections i’ve argued that elga’s and lewis’ positions lead to highly counterintuitive consequences. in this section i’ll consider some further reasons for favoring some of these stances over the others, and look to see if a skeptical scenario can be raised against compartmentalized conditionalization as well. . continuity in section three we saw that we need a continuity principle to keep our credences from varying wildly as time passes. as with any constraint on credences in a bayesian frame- work, this principle can be reformulated as a constraint on our priors—as a principle which only allows priors such that a subject with those priors who updates properly will always have credences that satisfy the original constraint. how severe a constraint on our priors does a continuity principle impose? in section four we saw that almost all of our purely self-locating changes are boring purely self-locating changes, where each old alternative at a world is replaced with a new one centered on the same individual but a later time. likewise, we saw that at almost all of our doxastic worlds we only have one doxastic alternative. restrict our atten- tion to these cases: boring purely self-locating changes at worlds with one alternative. continuity requires a hefty constraint on our priors if we adopt centered conditional- ization, in both these cases and the general case. what if we adopt compartmentalized conditionalization? if we adopt compartmentalized conditionalization, continuity is free in these cases. compartmentalized conditionalization divides the credence allocated to a world among the alternatives at that world in accordance with their priors. but if there’s only a single alternative at a world, then it will be assigned all of the credence allocated to that world, regardless of its prior. so in the vast majority of cases we deal with—boring changes at worlds with one alternative—continuity falls right out of the dynamics! this is a mark in favor of compartmentalized conditionalization. . reflection van fraassen ( ) has suggested that we adopt a reflection principle as a constraint on rationality. the reflection principle is, roughly, that your conditional credence in h given that your credence in h will become x, should be x. in the special case where you believe that your credence in h will be x, reflection entails that your current credence in h should be x. as with conditionalization, one can consider de dicto and de se versions of reflection, with h ranging over de dicto and de se propositions, respectively. unlike conditionaliza- tion, the de se version of reflection is not very interesting. the de se version of reflection is untenable, and there’s no straightforward way of fixing it up. consider the centered proposition that it’s p.m. the de se version of reflection requires that if you believe that at some time in the future you’ll believe it’s p.m., you should believe it’s p.m now. but it can be rational to both believe that it’s p.m. now and believe that at some time in the future you’ll believe it’s p.m. you might, for example, be in possession of a reliable watch. from now on, let us restrict our attention to the de dicto version of reflection. unrevised de dicto conditionalization along with some further assumptions, such as that one’s potential evidence forms a partition of possible worlds, entails reflection. revised de dicto conditionalization violates reflection, since it allows evidential instances to add doxastic worlds; i.e., allows a subject to lose information about the world. i say “roughly” because this version of the principle is narrower than the principle of reflection van fraassen ( ) now subscribes to. van fraassen now subscribes to a principle he calls general reflection, from which the above principle can be derived as a special case. intuitively, what one wants is a tie between what one thinks their future credences in a centered proposition will be, and one’s current belief in some suitable correlate to that centered proposition. but it’s hard to see what such a ‘suitable correlate’ would be. it seems, for example, that such a correlate would not be representable as any kind of belief in the standard lewisian framework (as a set of centered worlds). this is the standard claim made about the relationship between conditionalization and reflection. weisberg ( ) argues that this is not the case; what the entailment requires is not that the subject conditionalize, but that she believes she conditionalizes. likewise, the entailment requires that the subject believes her potential evidence forms a partition. for simplicity, i’ll continue to write in this section as if the standard claim were correct; it is a simple matter of introducing the appropriate ‘if she believes’ clauses to bring the discussion here in line with weisberg’s claim. again, see arntzenius’ ( ) shangri-la example for a case in which this happens. centered and compartmentalized conditionalization also violate reflection for this reason. however, centered conditionalization can violate reflection even if we exclude belief changes that add doxastic worlds. this is not very surprising; de dicto conditionaliza- tion is closely tied to reflection, and centered conditionalization and de dicto condition- alization conflict. we’ve already seen an example of such a violation in the sleeping beauty case. given centered conditionalization, your sunday credences that the coin will come up heads/tails is / , even though you know that your credences on monday in heads/tails will be / . compartmentalized conditionalization avoids some of the reflection violations of cen- tered conditionalization. on compartmentalized conditionalization, potential purely self- locating changes that add or eliminate doxastic alternatives don’t bring about violations of reflection. so in the sleeping beauty case your credence in the proposition that heads/tails will come up does not violate reflection: your credence in heads/tails on sunday is / , and you know your credence in heads/tails on monday will still be / . but compartmentalized conditionalization also violates reflection in some ways that centered conditionalization does not. this is surprising since de dicto conditionaliza- tion is built into compartmentalized conditionalization, and, given some apparently in- nocuous assumptions, de dicto conditionalization entails reflection. compartmentalized conditionalization doesn’t entail reflection because one of the assumptions required for the entailment fails when irreducibly de se evidence is taken into account. namely, in cases where evidence can be irreducibly de se, the potential evidence need not form a partition of possible worlds. take a case like the sleeping beauty case, but with the following twist: if the original coin toss comes up tails, they’ll put you in a black room on monday and a white room on tuesday. if the original coin toss comes up heads, another coin will be flipped to determine whether to put you in a black room or a white room on monday. in this case one’s potential evidence is either waking up and seeing a black room or waking halpern ( ) considers some further issues regarding reflection in the case of subjects who, unlike the subjects we’re considering here, need not have a sense of time passing. he shows that an agent who satisfies a condition he calls perfect recall and updates by compartmentalized conditionalization will satisfy a version of reflection, while an agent who satisfies perfect recall but updates by centered conditionalization will not. up and seeing a white room. these two pieces of evidence don’t form a partition of possible worlds because they’re not mutually exclusive with regards to worlds. both pieces of evidence are compatible with the worlds where the original coin toss comes up tails: seeing black with the tails and monday alternative, seeing white with the tails and tuesday alternative. in this case compartmentalized conditionalization violates reflection: your credences in heads and tails on sunday will be / , but you know that on monday after you open your eyes your credences in heads and tails will be / . if you see a black room, you’ll eliminate half of your heads worlds—the worlds where the second coin toss came up such that they put you in a white room. you’ll also eliminate the tuesday alternatives at your tails worlds, but this won’t eliminate any of the tails worlds. so on compartmentalized conditionalization, if you see a black room your credence in tails will go up. likewise, if you see a white room, you’ll eliminate half of your heads worlds, and eliminate the monday alternatives at your tails worlds. but none of the tails worlds will be eliminated, so again your credence in tails will go up. centered conditionalization will also violate reflection in this case, of course, for the same reason it violates reflection in the standard sleeping beauty case. on centered conditionalization, though, this violation will take place between sunday and when you wake up on monday, and no further violation will take place between monday before you open your eyes and monday after you open your eyes. on compartmentalized conditionalization, the opposite is the case: no reflection violation takes place between sunday and monday before you open your eyes, but a reflection violation does take place between monday before you open your eyes and monday after you open your eyes. elga’s position has struck many as strange because it allows changes in a subject’s de dicto beliefs without, intuitively, the subject having gained or lost any information about what the world is like. in the black and white room case, for example, your credence in heads and tails changes before you open eyes, even though, intuitively, you have the same information about what the world is like as you had before you went to sleep. on the account i favor there is no such oddity. in the black and white room case, there’s no change in your de dicto beliefs until you open your eyes and see that you’re in (say) a black room. and it’s this de dicto information—that you’re not in a heads and white room world—that directly brings about the change in your de dicto credences. if there’s no de dicto information to be had—as in the sleeping beauty case—then there’s no change in your de dicto credences, and no violations of reflection. i take this to be a mark in favor of compartmentalized conditionalization. i’ve focused on elga’s account, but lewis’ account has the same deficits. while lewis does not allow the addition of doxastic alternatives to change our beliefs about what the world is like, he does allow the elimination of doxastic alternatives to change our beliefs about what the world is like. thus he is open to the same criticisms: he allows changes in a subject’s de dicto beliefs without, intuitively, the subject having gained or lost any information about what the world is like. . the varied brains argument reflection considerations aside, the black and white room case raises a natural worry for the account i favor. i offered the many brains argument as a criticism of elga’s / response to the sleeping beauty case. in the black and white room version of sleeping beauty compartmentalized conditionalization also ends up assigning / credences to heads and tails. is there an argument analogous to the many brains argument against compartmentalized conditionalization? yes and no. let’s look at how such an argument might go. the many brains argument itself won’t work because on compartmentalized conditionalization multiplying alternatives at a world doesn’t increase the likelihood of that world. as long as the set of doxastic worlds remains the same, our credences in the respective worlds will remain the same. to get an argument analogous to the black and white room case, we need an argument where the normal worlds are eliminated but the alternative multiplying worlds are not. so consider the following: the varied brains argument: assume your credences are divided between two kinds of worlds, normal (n) worlds and strange (s) worlds. among all these worlds there are n subjectively distinguishable experiences, e through en, that you might experience in the next second. in each of your doxastic s-worlds scientists are creating n brains in vats in the following second, each one compatible with some ei. in your doxastic n-worlds you have no subjective duplicates, but you have some n- world compatible with each ei. now, at the end of a second you’ll have experienced some e, say e . this will eliminate the doxastic n-worlds incompatible with e , i.e., the ones that were compatible with e through en. on the other hand, all of your doxastic s-worlds are compatible with e , so no doxastic s-world will be eliminated. by compartmentalized conditionalization, your credence in the s-worlds relative to the n-worlds will increase. we can extend this case by replacing ‘second’ with longer and longer units of time, and as the unit of time grows larger, the number n of distinguishable experiences you might experience during this period likewise grows larger. by making the unit of time arbitrarily large, we can get a case in which on compartmentalized conditionalization one’s credence in the s-worlds grows arbitrarily large. how bad is this? one might question whether this result is counterintuitive. this is an interesting, if murky, question. but it is worth looking at how things stand if we decide that the result is counterintuitive. in the varied brains case, d(s) gains on d(n) because of the artificial way in which the doxastic worlds have been selected: all the strange worlds under consideration are ones that will end up matching what we experience, whereas many of the normal worlds that are considered won’t end up matching what we experience. if we restricted the normal worlds to those compatible with e , d(s) wouldn’t gain on d(n). likewise, if we placed no restrictions on which strange worlds were allowed, then e would eliminate lots of strange worlds as well as lots of normal worlds. whether d(s) gains on d(n) depends on which s and n-worlds are doxastic worlds—which worlds our priors and evidence lead us to believe could be ours. and it’s reasonable to think that d(s) will not gain on d(n) for people with doxastic worlds like ours. skeptical results can be roughly divided into two kinds. first, there are results which entail that people like us in situations like ours should be lead to skepticism. second, there are results which entail skeptical consequences for people in outlandish situations, but which have little bearing on people like us. i take it that the first kind of result is worse than the second. our general sentiment is that our intuitions in outlandish situations are less reliable—and thus easier to discard—than our intuitions in situations we’re familiar with. likewise, it’s easier to bite the bullet with counterintuitive cases that have little impact on our everyday lives. the varied brains argument is a result of the second kind; it entails that people with certain idiosyncratic doxastic set-ups will come to believe something counterintuitive. the many brains argument, on the other hand, is a result of the first kind; it entails that people like us should come to believe that we live in a strange world. so the skeptical arguments considered weigh more heavily against elga’s account than they do against the account i favor. what about the sadistic scientists argument? this too is a result of the second kind. while people like us will become more and more sure we’re not in a ‘diminishing’ world, this will have little effect on overall belief distribution since our credences in such possibilities are so small. only people whose initial credence in these strange worlds are high will be lead to highly counterintuitive results. so the skeptical arguments, considered in isolation, don’t leave us with a reason to favor the account i advocate over lewis’ account. it is other considerations, such as the prima facie plausibility of the view, the implications with regards to reflection and continuity, etc., that will decide between the two views. a choice the counterintuitive aspects of elga’s and lewis’ responses can be brought together into a single case: the up-and-down case: some scientists will flip a fair coin tonight. if it comes up tails, then every day from now on the scientists will create n brains in vats in states subjectively identical to yours at noon, and will destroy n of the brains they’ve created at midnight. if it comes up heads, no brains will be created or destroyed. if you endorse elga’s solution to the sleeping beauty case, then your credence that the coin came up tails will converge to , regardless of your evidence (knowledge of objective chances, etc.) to the contrary. if you endorse lewis’ solution to the sleeping beauty case, then your credence that the coin came up heads will converge to , again regardless of your evidence (knowledge of objective chances, etc.) to the contrary. i take both of these outcomes to be counterintuitive. intuitively, our credences should remain / throughout. intuitively, purely self-locating changes don’t provide us with any new information about the world, and shouldn’t change our credences about what the world is like. intuitively, purely self-locating changes shouldn’t change our credences in propositions. call this claim. there are two ways to satisfy claim. first, we can reject centered conditionalization and adopt a different belief dynamics, preferably one more compatible with claim. one choice for such a dynamics is compartmentalized conditionalization, which satisfies claim automatically. once we’ve entertained the notion of compartmentalizing beliefs, however, a number of possibilities arise, such as belief dynamics with several layers of compartmentalization, belief dynamics that compartmentalize groups of worlds or within worlds, etc. compart- mentalized conditionalization is uniquely picked out if we add two further constraints. first, require that the dynamics be compatible with de dicto conditionalization. this entails that the dynamics must first compartmentalize at the level of worlds. second, require that the dynamics treat sleeping beauty cases the same way as duplication cases, duplication cases the same way as fission cases, and so on. that is, require that the dy- namics treat shifts in the centered worlds at a world uniformly, taking into consideration only the change in numbers of centered worlds and the relevant priors, not the features of the centered worlds. this eliminates any dynamics that compartmentalize non-trivially within worlds. only compartmentalized conditionalization meets these two constraints. neither of these constraints is beyond question, but i take them both to be prima facie plausible. so i take compartmentalized conditionalization to be a natural choice for the dynamics. second, we can keep centered conditionalization and constrain our priors such that our belief changes will be compatible with claim. this includes rejecting the con- this is only non-trivially possible for agents who have a sense of time passing. for these agents, priors in alternatives can be contrived such that claim is non-trivially satisfied. tinuity principles which elga’s and lewis’ arguments require to go through. but just rejecting these principles isn’t enough. this option requires adopting a strengthened version of the increasing no-evidence principle: in cases of purely self-locating change where the number of alternatives at a world increases, decreases, or stays the same, our credence in that world should remain the same. this general no-evidence principle entails claim. which of the two options should we choose? i suggest that we choose the first op- tion and adopt compartmentalized conditionalization. if we adopt compartmentalized conditionalization we get claim for free. if we adopt centered conditionalization we only get claim after imposing draconian restrictions on our priors, restrictions that in effect make our belief changes look like they’re being governed by compartmentalized conditionalization. what’s the point of adopting centered conditionalization if what we really want is for our beliefs to behave as if we’d adopted compartmentalized condition- alization? i’d like to thank frank arntzenius, maya eddon, adam elga, hilary greaves, john hawthorne, david manley, tim maudlin, adam sennet and jonathon weisberg for valuable comments and discus- sion. in particular, i owe much to david manley, for raising the black and white room case, and to tim maudlin, who’s many worlds argument inspired my interest in these issues. finally, i owe a special thanks to frank arntzenius for comments on a number of drafts, and endless barroom discussion. the bulk of this work was completed with gracious funding from rutgers university in the fall of . references arntzenius, f. 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( ). “the transcendence of artistic beauty over natural beauty”, vol: issue: pp: - keywords: the beauty of nature; artistic beauty, subjectivity. article type review article the transcendence of artistic beauty over natural beauty arrived date . . accepted date . . published date . . siyu*shao* abstract in terms of aesthetic experience, natural beauty and artistic beauty are the most important concepts in people's aesthetic activities.according to the differences of aesthetic objects themselves, natural beauty is a natural thing, while artistic beauty is integrated into human activities. the reason why the artistic beauty transcends the natural beauty is that the natural beauty only has the perceptual form but does not have the idea, while the artistic beauty embodies the subject status of human beings in the content and form. introduction whether the natural beauty or the artistic beauty has higher aesthetic value has always been a question debated by many scholars since ancient times. art recognizes and displays human ideas in a perceptual way, reconciling concepts and external images into a unified whole. art is presented by the idea of filling in the objective world perceptual materials, but the limitations of the objective world cannot embody the concept of absolute limitlessness. philosophy is the logical system, consciousness of perceptual intuition is a necessary source of logical concept, according to the views of hegel, absolute concept has experienced three stages, art, religion and philosophy respectively through the perceptual representation, and the way of concept to show the concept from perceptual to rational development trend. art belongs to the product of human consciousness. to recognize the view that artistic beauty surpasses natural beauty is to recognize the subject status of human beings in aesthetic experience. literature inspiration of natural beauty to artistic beauty the process of conscious creation shows how the human idea makes itself an objective thing and integrates essence and phenomenon into a whole. in the process of discussing such a combination of universality and particularity, the primary form of the idea of beauty is first placed on the natural beauty, then the idea transcends the natural beauty and then reaches the artistic beauty. from the perspective of aesthetic object, the beauty of nature is the externalization of human ideas, and the beauty of art is the result of the transformation of nature by human ideas. the discussion on the relationship between artistic beauty and natural beauty in the field of western aesthetics can be traced back to the ancient greek period. hegel's exposition of natural beauty is a gradual evolution from the lower natural objects to the higher natural objects, and finally falls to the human society to analyze gradually. nature is the first object of human observation, but the in-itself cannot prove the existence of the absolute idea. in hegel's exposition of natural beauty, it is deduced from the evolution * changchun institute of technology, @qq.com, jilin/china volume: , issue: , october issjournal.com https://orcid.org/ - - - and development of nature that natural beauty also presents several levels rising from low to high. according to hegel, "this level of beauty has an intrinsic necessity and is a progressive process consistent with reason. the natural stage is only a preliminary stage in the development of the absolute idea. natural beauty is the result of the idea in its latent stage externalizing itself. "the most superficial objective existence of the idea is nature, and the first kind of beauty is natural beauty (guangqian, ). [ hegel's "aesthetics", the first volume, zhu guangqian, the commercial press, second edition in november , on page ] therefore, natural beauty is only the initial stage, and it will inevitably ascend to a higher level of beauty with the development of ideas. german classical aesthetics generally believes that beauty exists in human experience, while artistic beauty is the perceptual manifestation of ideas, it does not deny the role played by external images in the formation of aesthetic experience. in modern aesthetics, although the transition from the noumenon of "i think" to the noumenon of "will" has not been established in hegel's period, the author thinks that this tendency has already appeared in hegel's theory. for a long time, since the creation of baumgarten in , the concept of "beauty" was considered to be only about sensibility. from kant's analysis of beauty, the perception of beauty is the opposition to logical thinking, until croce's "intuition theory", beauty is only the sensory experience of perceptual image. hegel pointed out that "a work of art is not merely an object of sensibility, but is appealed only to the grasp of sensibility. on the one hand, it is perceptual; on the other hand, it is basically appealed to the mind, which is also moved by it and gets some satisfaction from it." (zhongyuan, ). [ hegel's "aesthetics", the first volume, zhu guangqian, the commercial press, second edition in november , on page ] that is to say, the mind will be touched by art, which shows that thought plays an important role in artistic creation, and artistic works should be the unity of sensibility and rationality. the outward manifestation is either the manifestation of the material sensibility or the formation of the reason by the inner idea. but why nature is beautiful is not because of itself or because it was created to be beautiful. the beauty of nature is endowed by the aesthetic consciousness of human beings, and the beauty is the experience obtained by human senses. it can only exist in human consciousness. however, natural objects cannot actively convey the information of beauty to people, so it needs the active exploration of human perception. it is possible for the human emotion to combine the parts of nature into a whole in consciousness, but it is not at first recognized by the emotional expression of the soul. in other words, from hegel's point of view, the beauty and non- beauty of natural objects only exist in people's consciousness, and nature itself does not have the ability to manifest ideas. natural beauty is reflected in the human mind in the process of understanding natural objects. as mentioned above, the beauty displayed by natural objects exists for aesthetic consciousness, while living natural objects are only beautiful for other objects. because its beauty is endowed by the human idea, the image of beauty needs to be perceived by the human consciousness, and the aesthetic experience needs to be under the control of the human idea. therefore, there is no beauty or unbeauty in simple natural objects. only when people's consciousness judges them, the beauty of nature can be revealed. in hegel's view, nature is beautiful, is because people, the understanding of the practice of human beings in understanding and reforming nature, its philosophy gives natural things, people think that nature is the essence of beauty is the human spirit to mapping of natural things, so people in observing natural plants, the natural thing in the world and the human mind will resonate, and feeling of aesthetic pleasure from natural objects. the beauty of nature lies in gives the idea of people to the natural thing in the world, originated in human understanding of nature of aesthetic practice, the existence of most things in nature is comfortable, humans also exists in nature, but is the existence, human can change the appearance of natural objects through practice, and the practical ability to improve natural thing in the world can be transformed into and consistent state of mind activity. that is to say, man injects his mind into nature through practice. it is only when a man has an idea of his environment that he feels comfortable in it. the two are integrated by a common idea, rather than the existence of natural objects and people in relative isolation. natural thing in the world to meet human practice provides a material basis, but the natural thing in the world is not completely in accordance with the will of the human growth, human also need to learn a skill to the natural barrier in plants, according to their own will to transform natural thing in the world to make it fully satisfy human volume: , issue: , october issjournal.com needs, from this perspective, the product of the mind is higher than the natural thing in the world (xingyun, ). art is the transformation of nature by ideas art is the first way for human beings to express their perceptual knowledge. it can depict objective things or externalize ideas into perceptual images. therefore, art can not only contain perceptual elements, but also show rational thinking. it can reconcile the finite objective world with the infinite spiritual world. the greatest value of art lies in its ability to show abstract ideas as concrete images. however, if art is to occur in an objective form, it must be completed under the guidance of the idea. only the idea can organically unify the subject and object. hegel pointed out that "in nature, the concept is derived from reality and thus becomes the idea in several ways. first, the concept is directly submerged in the objective existence, so that the conceptual unity of the subject cannot be seen, and is completely transformed into the sensible material thing without soul." (linlin, ). the first in the existing way of the concept of material only reflect rather than from the literature, it exists in the form of its own internal cause in accordance with established, completely don't reflect the content of spirit, it couldn't see the soul. secondly, the higher level of natural objects can make the concept present a free state, which is embodied in the fact that each difference surface of the existence mode of natural objects can exist independently. although it is absorbed in the whole, it does not need to be restricted by other difference surface. in other words, in the natural objects of this stage, the different aspects of the concept show a dialectical unity. all the different aspects of the concept exist independently and are dominated by the same system. the actual existence mode of the idea should be the organic natural things that can move like every celestial body, while the dead inorganic natural things cannot show the idea, and obviously the dead inorganic things cannot prove themselves to have the idea. (yuegui, ). therefore, the manifestation mode of the idea in natural objects is a mode with activity ability, and life is the objective existence form of the idea in nature. in ancient greece, art was understood as a collection of various skills, and the development of art level can reveal whether a nation's spiritual world is noble or not. during the renaissance, when art flourished, artistic works began to express the realistic spirit of human beings and became the force to push forward human history and civilization. in the field of philosophy, kant made a systematic exposition of aesthetic judgment for the first time. and kant's views on aesthetics, such as taste, genius legislating for art, natural beauty and artistic beauty, have exerted great influence on the development of aesthetics in later generations. what artistic beauty shows is the truth, which is contained in the individual and the representation. although it may be covered by the external image, artistic creation will pull out the inner essence of the truth and then show it to the world in the form of sensibility after people's soul summary and sublimation. artistic creation is to extract the characteristics of natural things in the objective world and sublimate them in the spiritual world. in artistic creation, the objects of the objective world are reproduced in artistic images and show a unified form with the spirit of the creator. artists in the creation of activities, their perceptual knowledge of the objective form of things, to the artistic image reproduced in the works of art. admittedly, reproduction should reflect the elements contained in natural things, but the reproduction of artistic creation is by no means a completely mechanical copy, but should be re-processed through the artist's perceptual understanding of natural things, reproduced in accordance with the concept of art creators, and reproduced in the way of artists' creative labor. starting from the primitive art, the expression technique of art usually abandons the things defiled by chance and external shape, and only transmits the most ideal form of things, which is still continuing today. in order to achieve the ideal form of a work of art, it is necessary to extract a concept that can truly express its own essence, while the external image of chance cannot achieve true harmony with the idea. art is the spiritual activity of unity of opposites between perceptual image and idea. the idea is still in the primary stage in the symbolic art, which shows a very vague form. the idea expressed in symbolic art is very abstract, and the idea is only embodied as the symbol or symbol of objective things. the referential relationship between this art form and natural things is a simplified form extracted from the perceptual knowledge of natural things. therefore, symbolic art cannot fully show the concept. volume: , issue: , october issjournal.com with the continuous development of art, it will further develop to the classical art. the concept of classical art and the perceptual form have reached a high degree of unity. the absolute idea must exist within the mind itself, and too clear a picture of the external world limits the extent to which the idea can be expressed. therefore, the development of art also needs to abandon the referential relationship between content and form and return to the spiritual realm from the external form. romantic art overcomes the deficiency of classical art in concept development by breaking the unity of form and content. in romantic art, the idea reflects its own independence and no longer permeates into the external perceptual form. although art is the perceptual manifestation of the idea, romantic art mainly reflects the inner spiritual activity, and the perceptual image cannot fully show the content produced by the mind. the classification of art is to grasp the relationship between art and idea, and the basis of the classification of art types is the relationship between idea and the image it shows. this type is known as the symbolic art type. in this type, the idea is only attached to perceptual materials, and the artistic works are not produced in accordance with what the idea wants to express. in this type of artwork, there is a negative relationship between ideas and art. works of art only express ideas in an abstract way, and ideas do not dominate the creation of artistic works. therefore, artistic works cannot fully conform to ideas. the second type of art is classical art, which overcomes the defects of symbolic art. in classical art, ideas are represented in images in a free and appropriate way. the third type of art is romantic art. hegel thought that the romantic art appeared the defect of the symbolic art in the higher stage. it destroys the mode of unity of idea and image established by classical art, because the limitation of art itself cannot express the infinity of idea. romantic art can be understood as the unity of spirit and essence in the mind. although the idea is capable of uniting sensibility and reason, hegel believes that the idea of art transcends its perceptual form and that art is not the most perfect form of expression of the idea. art must adhere to the limited form, while the infinite of the idea needs a more free carrier. in the aspect of the idea, the content and meaning of art are the same as religion and philosophy, and they are both ways of knowing and expressing themselves. however, the difference between the three lies in the degree of manifestation of ideas. among them, art is the lowest, which only has the form of sensibility. while philosophy is the highest, it can think freely in the spiritual world. art and religion are united in philosophy. hegel developed the idea from the perceptual objective world and finally returned to his own spiritual world. at this time, the absolute idea is the most real. the idea is the product of the spiritual realm. it can exist independently in the spiritual world and negate and transcend its perceptual form. the idea of beauty is only the most superficial stage of the development of the absolute idea. compared with religion and philosophy, it needs further exploration in the spiritual world to truly find the connotation of the absolute idea. the idea is the cornerstone of art art, because of its freedom, can become a stage in the development of the absolute idea. art is a form of representation of ideas, which can realize self-knowledge and act on objective things. artistic creation can reconcile the limited objective things with the unlimited freedom of the spiritual world, its highest pursuit is to reveal the truth of the soul. the idea is the soul of art, and the most important role of art for the idea lies in the manifestation. if the idea is to be transformed from the mind into an objective thing, artistic creation needs to be carried out under the guidance of the mind, so that the artwork can show the freedom of the mind through the guidance of the idea. the essence of beauty is the unity of spirit and nature. nature transformed by spirit is beauty or artistic beauty. that is to say, what is revealed through art is the essence of beauty. artistic beauty is to endue the ideal to reality, art is the perceptual form of the idea, the idea is the rational inner art, although there are differences in the form of the two, but they are a unified whole. ideal is usually born in the reality, it is the most perfect form of reality that human beings expect. the whole world derives from the idea of man, and it is all-encompassing. the absolute idea constitutes the essence of the real world and is also the core of hegel's philosophy system. but the idea volume: , issue: , october issjournal.com cannot directly manifest itself, it must be indirectly manifested through a medium, and beauty can be used as the carrier to make the idea in an intuitive state. although art is manifested in the form of sensibility, the foundation of artistic creation is rational. the artist's understanding of beauty is based on sensibility, while the grasp of perceptual materials requires the control of rationality. only through the rational grasp of the universal concept, artistic creation has the idea of the perceptual form of the starting point. the idea determines the specific content of the art, and the concreteness of the perceptual image limits the idea within the specific scope. from the perspective of idea and art, art has developed from symbolic art to romantic art, while with the development of art, the idea has gradually surpassed the status of perceptual image from the vague form at the beginning. from the perspective of the absolute idea, although the idea in romantic art has a high degree of perfection, the limitation of perceptual image is not enough to fully meet the needs of the idea. at this time, the idea must withdraw from the perceptual world and turn to seek higher forms such as religion and philosophy to understand itself. the concept of art can be understood as the connotation that the artist wants to express in his works, while the perceptual exterior is the form that the works of art are presented to people for appreciation. however, the content to be expressed by artistic works is the existence mode of ideas, which needs the works endowed by creators. natural beauty does not reveal its ideas, but only its perceptual exterior. and the idea of artistic beauty is in harmony with the human mind can make the content and form into a unified whole. in hegel's historical period, there is a clear referential relationship between artistic works and natural objects, so he believes that the contents of artworks must be presented in the form of the unity of subjectivity and objectivity. a work of art should present a specific and corresponding perceptual form, which must be single, complete and independent, rather than a common characteristic of a class of things. from this point of view hegel acknowledges that art can represent abstract content. art is able to express the true content, not because it happens to have a similar external form, but because the concrete content already contains the element of perceptual representation. what art presents to people is the perceptual thing, which is essentially the content of the spiritual activity of the artist. when the artistic image is regarded as representing the inner activity, the artistic image and the content can be completely consistent. pure natural things do not exist for the purpose of expressing content. since the beauty of natural things is not recognized by people, it can still exist independently, while artistic works cannot exist independently. it echoes with the heart. a work of art is the external representation of the heart, and the idea of the heart is the content of the work of art, which is a coordinated and unified whole. when nature and art want to show their own beauty, the former product needs to internalize the perceptual knowledge into consciousness, while the latter needs to externalize the product of the mind into the objective world. the reason why the beauty of art is higher than that of nature is that hegel believes that the mind and its products are higher than that of nature and its products. from the perspective of the development process of the concept of beauty, people's understanding of natural beauty is earlier than that of art. natural beauty is presented to people in a perceptual and intuitive way, while artistic beauty is involved in the activities of the human mind. art can fully show the idea, which is the advanced stage of the development of the idea. the thing of nature has no complete self- consciousness, its beauty is in itself, while the beauty of art is for itself. since art reflects the activity of the mind, beauty can only exist in the mind of human beings. unrecognized nature does not matter whether there is natural beauty or not. artistic creation is to convey the idea of beauty and produce it according to the idea of beauty, so artistic beauty is closer to the idea than nature. however, from the perspective of the development stage of the idea, art is higher than nature in the evolution stage of the idea. it is the product of the mind and more suitable to show the idea than nature. art is bound to have the idea and understanding of the creator, the beauty of art in human society, than the natural beauty to convey the role of beauty. but hegel does not believe that art is the best form to show the idea. in hegel's philosophical system, the perceptual form of human consciousness is formed in the process of art, which is a perceptual expression at an earlier stage. the further development of the idea into a higher form depends on religion, for the religion of the mind can understand the form of the idea in a higher way of thinking. but religion is only a transitional stage, and philosophy is the most perfect form to interpret the ultimate idea. [ ]thus it can be seen that art is not the most suitable way for the volume: , issue: , october issjournal.com soul to express ideas in perceptual forms. therefore, art is only the initial stage of the development of ideas, while religion and philosophy are higher than art. conclusions and recommendations although the idea can unify the sensibility and rationality, the idea of art transcends its perceptual form, and art is not the most perfect form of expression of the idea. art must adhere to the limited form, while the infinite of the idea needs a more free carrier. in the aspect of the idea, the content and meaning of art are the same as religion and philosophy, and they are both ways of knowing and expressing themselves. art and religion are united in philosophy. hegel developed the idea from the perceptual objective world and finally returned to his own spiritual world. at this time, the absolute idea is the most real. the idea of beauty is only the most superficial stage of the development of the absolute idea. compared with the natural beauty, it further plays a dominant role in the field of aesthetic appreciation. acknowledgement suppoted by changchun institute of technology theme fund “study of the double modernity of western modern art”. references guangqian, z. ( ). hegel's "aesthetics", the first volume, the commercial press, beijing. linlin, s. ( ). on the dialectic relationship between the beauty of nature and the beauty of art -- rethinking hegel's view that the beauty of art is superior to the beauty of nature. contemporary fiction monthly ( ), - . xingyun, g. ( ). on the superiority of natural beauty over artistic beauty -- hegel's mental process of the superiority of artistic beauty over natural beauty and his reflection on it. journal of wuhan university: humanities edition, ( ), - . yuegui, h. ( ). on the relationship between hegel's natural beauty and artistic beauty. changjiang series, ( ), - . zhongyuan, w. ( ). aesthetic crisis, "back to kant" and the identity of natural beauty and artistic beauty. shandong social science ( ), - . volume: , issue: , october issjournal.com introduction . books mh ab the second half of access denied consists of detailed descriptions of internet use, regula- tions and censorship in eight regions of the world, and in each of different countries. the oni found evidence of censorship in of those . for the other countries, it sum- marizes the legal and regulatory framework surrounding internet use, and tests the results that indicated no censorship. this leads to pages of rather dry reading, but it is vitally important to have this information well- documented and easily accessible. the book’s data are from , but the authors promise frequent updates on the oni website. no set of internet censorship measures is perfect. it is often easy to find the same infor- mation on uncensored urls, and relatively easy to get around the filtering mechanisms and to view prohibited web pages if you know what you’re doing. but most people don’t have the computer skills to bypass controls, and in a country where doing so is punishable by jail — or worse — few take the risk. so even porous and ineffective attempts at censorship can become very effective socially and politically. in , barlow said: “you are trying to ward off the virus of liberty by erecting guard posts at the frontiers of cyberspace. these may keep out the contagion for some time, but they will not work in a world that will soon be blanketed in bit-bearing media.” brave words, but premature. certainly, there is much more information available to many more people today than there was in . but the internet is made up of physi- cal computers and connections that exist within national boundaries. today’s internet still has borders and, increasingly, countries want to control what passes through them. in documenting this control, the oni has performed an invaluable service. ■ bruce schneier is chief security technology officer for bt counterpane, santa clara, california. he is author of beyond fear: thinking sensibly about security in an uncertain world. josie glausiusz a pudgy, pink, pig-like creature, lacking a head but sprouting a tuft of unruly hair, sits in a corner of the museum of modern art (moma) in new york. epidermits, a stubby- legged quadruped, was purportedly spawned from a skin-and-hair-cell culture grown from a human cheek swab, and is fed on a ‘sustain solution’ infused through its tail. if carefully nurtured, it could be expected to live as long as “a large dog or a donated kidney”. so says designer stuart karten, who claims that his ten-centimetre- long, yet-to-be-realized organism could be a pet of the future. our ability to incorporate such fantastic ideas into everyday life is the subject of moma’s new exhibition, design and the elastic mind, which explores the myriad ways in which our minds rapidly adapt to technological changes. this marvellous hodge-podge of exhibits comprises creations that range in size from nano-scale smiley-faces stitched together from viral dna, to an imposing five-metre-tall sculpture by chuck hoberman called emergent surface — a screen of twisting and unfolding slatted steel panels that move in response to changes in light. practical gadgets sit beside whimsical pieces such as the ‘smell augmentation’ plugs that artist susana soares invites us to stuff up our nostrils. at their best, these devices marry beauty and utility. martin and erik demaine, a father-and-son team from the massachusetts institute of technology (mit), created computational origami — delicately folded, interlocking paper loops that demonstrate the use of computer-aided design to squeeze large objects into small spaces. a similar concept underlies robert lang’s origami models of the fresnel lens for the eyeglass space telescope (a mothballed project of the lawrence livermore national laboratory in california). the lens, if realized, could have been scrunched up, launched and then expanded in space to a diameter of metres — roughly the length of an american football field. elegance and expediency also underlie the sonumbra sculpture created by rachel wingfield and mathias gmachl, a tree-like ‘sonic shade of light’ that transforms peoples’ movements via software into serene sounds that are reminiscent of those produced with a tibetan singing bowl. solar cells embedded in the green, umbrella- like shade of sonumbra harvest energy during the day to power the lights at night. some of the most compelling items in design and the elastic mind are simple, yet could prove essential to populations that lack basic equipment. bernhard weigl’s credit-card-sized ‘lab on a card’ can diagnose an intestinal infection from a small faecal sample in minutes. emili padrós’s ‘non-stop shoes’ use the energy generated from walking and stair-climbing to run lamps and radios. similarly, the green-keyed xo laptop computer designed by mit’s media lab is “lighter than a lunchbox” and has a battery that can be recharged by pulling a cord wrapped like a yo-yo. it is being distributed to schools in uruguay, afghanistan, cambodia and mexico, among others, as part of the ‘one laptop per child’ project, a non-profit programme to deliver laptops to the world’s poorest children in remote areas. what makes the exhibition so electrifying is the imagination that drives these innovations. a charming example is a series of drawings inspired by artist alan outten, who challenged british primary-school children to design the future. their inventions included ‘super-human mermaid’, a genetically engineered human with the genes, gills and tails of a fish “in case the world floods due to pollution”, and ‘the apple phone’, a tree with man-made seeds that “use nature as their energy source” to grow apple-like telephones, “so if you are having a private conversation, you just eat the apple”. to quote outten, i left the exhibition “with a sense that creativity and design are safe in the hands of the next generation”. ■ josie glausiusz is a journalist based in new york. design and the elastic mind runs at the museum of modern art, new york, until may (www.moma.org). exhibition beauty meets utility at moma u c la /c o ll o id ia ; i m a g e b y t . g . m a so n /c . j . h er n a n d ez correction ken arnold’s review of the anatomist by bill hayes (nature , ; ) incorrectly said that the mother’s blood enters the fetal heart through a hole. in fact, this hole lets blood move from the right to the left atrium in utero and is sealed after birth. ‘colloidal alphabet soup’: these -micrometre-long polymer letters could be used to label individual cells. nature|vol | march b o o k s & a rt s beauty meets utility at moma note << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (none) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v 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( ) - , visual complexity and beauty appreciation: explaining the divergence of results marcos nadal enric munar gisÈle marty camilo josÉ cela-conde university of the balearic islands abstract although a number of studies have verified daniel berlyne’s ( ) pre- dicted maximum preference for intermediately complex stimuli, others have found that preference increased or decreased in relation to complexity. the objective of the present work was to assess whether differences in the kinds of stimuli used in prior studies or in the way complexity was defined could explain this divergence. in the first phase a set of stimuli varying in complexity, abstraction, and artistry was assembled. in the second phase participants were asked to rate the beauty of the stimuli. in the final phase the same participants rated of the stimuli on seven complexity dimen- sions. we failed to detect any meaningful influence of complexity on beauty ratings for any of the kinds of stimuli. however, our results suggest that there are three different forms of complexity that contribute to people’s perception of visual complexity: one related with the amount and variety of elements, another related with the way those elements are organized, and asymmetry. we suggest that each of these types of complexity influences beauty ratings in different ways, and that the unresolved relation between complexity and beauty appreciation is mainly due to differences in the conception, manipu- lation, and measurement of visual complexity. � , baywood publishing co., inc. doi: . /em. . .d http://baywood.com the knowledge that order and complexity influence people’s appreciation of beauty goes back at least to the ancient greeks. however, it was not until fechner’s ( ) work that this issue was systematically studied, paving the way for birkhoff’s ( ) mathematical approach, which predicted that appreciation would increase with order and decrease with complexity. although birkhoff accompanied his formulation of the aesthetic measure with detailed definitions of order and complexity, together with examples for a large number of polygons, eysenck ( ) reported considerably low correlations between predicted aesthetic measure and the beauty ratings actually awarded by people. in order to find a more satisfactory alternative, eysenck ( ) studied people’s responses to a broad number of geometrical figures. his results suggested that different features of those objects, related with complexity and order, could be used to predict the beauty ratings awarded by human participants. however, the relation between both factors was not the one predicted by birkhoff. in a simplification of his original formula, eysenck ( ) showed both order and complexity contribute positively to the appreciation of beauty. it was not until berlyne ( ) presented his influential framework that the study of complexity’s influence on the appreciation of beauty was based on firm psychological and neurobiological grounds. in brief, berlyne ( ) posited that the interaction of reward and aversion brain systems would lead people to prefer intermediate levels of complexity, which was defined according to such aspects as pattern regularity, amount of elements, their heterogeneity, or the irregularity of the forms (berlyne, , , ; berlyne, ogilvie, & parham, ). a considerable amount of research has since been conducted to test this hypothesis, employing diverse visual stimuli. some studies have been carried out with simple materials, such as geometric shapes (aitken, ; katz, ; vitz, ), or artificially generated images (heath, smith, & lim, ; ichikawa, ; markovic & gvozdenovic, ; stamps, ), varying along a specific, clearly defined, and objectively measurable complexity dimension. other studies have used artworks, though often including only a single class, such as abstract paintings (krupinski & locher, ; nicki & moss, ; osborne & farley, ), cubist artworks (nicki, lee, & moss, ), figurative images (messinger, ), or portraits (saklofske, ). these studies were not able to carry out such a straightforward measurement of complexity. a serious limitation of both sets of studies is that in most instances the number of participants was quite low (in some experiments as few as eight per condition) or the number of stimuli was reduced (only five in some instances). additionally, the large majority of them used correlational methodology, which precluded the proposal of causal explanations of complexity’s influence on aesthetic appreciation. the review of these prior studies reveals a considerable divergence in results. some of them did actually find the expected inverted u-shaped distribution of preference and beauty scores as a function of complexity. conversely, others found that preference and appreciation increased with complexity and, yet others, / nadal et al. found that ratings decreased as the stimuli’s complexity grew. we believe that two reasons could explain this disparity: differences in the kinds of materials used in prior studies, and the disparate ways in which they conceived, measured, and manipulated visual complexity. the objective of the present study was, therefore, to clarify the influence of visual complexity on beauty appreciation, and examine the role of stimuli features such as degree of abstraction and artistry. additionally, we wished to explore the notion of visual complexity. specifically, we addressed the following questions: (i) do people consistently rely on the same features to perform com- plexity judgments of diverse visual stimuli? (ii) is visual complexity reducible to a single measure or is it multidimensional in nature?, and (iii) do all forms of complexity influence beauty ratings in the same way? method participants all participants were students enrolled in their fourth or fifth year of psy- chology, philosophy, or history studies, who voluntarily took part in the experi- ments. we included no one who had received formal art training or had studied art history. participants were divided into two groups. the first one took part in the first phase of the experiment, aimed at reaching an adequate set of stimuli to be used in subsequent phases. the second group participated in phases two and three, which were designed to explore the relation among different kinds of visual stimuli, different levels and forms of complexity and aesthetic appreciation. group consisted of participants: men ( . %) and women ( . %). their ages ranged from to years, with a mean of . and a standard deviation of . . group included participants: men ( . %) and women ( . %). ages ranged from to years, with a mean of . and a standard deviation of . . materials visual stimuli we collected over , digitalized images, which were either abstract or representational, and either artistic or not artistic. the distinction between abstract and representational stimuli referred to the absence and presence of explicit content, respectively. artistic stimuli were reproductions of catalogued pieces created by renowned artists and exhibited in museums. following heinrichs and cupchik’s ( ) recommendation, we included images belonging to diverse styles and schools, such as realism, cubism, impressionism, and so on. as a guide for our initial selection we used the compendium movements in modern art from the tate gallery, london (cottington, ; gooding, ; malpas, ; visual complexity and beauty / thomson, ) and added reproductions of xviii and xix century american and european artworks. non-artistic stimuli included postcards, photographs of landscapes, artifacts, urban scenes, and so on, taken from the series of books boring postcards (parr, , ), photographs taken by ourselves, as well as digital images from the series of cds master clips premium image collection (ismi, san rafael, ca), used in industrial design, book illustrating, etc. stimuli selection and modification the initial set of images was subjected to a series of modifications in order to eliminate the influence of potentially confounding variables. only relatively unknown pieces were selected to avoid the impact of familiarity, as recommended by eysenck ( ). in order to avoid the influence of ecological variables we eliminated those stimuli that contained clear views of human figures and human faces, as well as those stimuli portraying scenes that could elicit strong emotional responses. the undesired influence of psychophysical variables was controlled by adjusting all stimuli to the same resolution of ppi, setting a common size of by cm, standardizing the color spectrum, and adjusting luminance to between and lx. stimuli that could not be reasonably modified to comply with this homogenization were discarded. finally, the signature was removed from all signed pictures. this process of stimuli selection and modification was carried out to leave us with images, of which were abstract artistic, were abstract non-artistic, were representational artistic, and were representational non-artistic. hardware and software all stimuli were presented to participants and their responses registered by means of a specifically designed software running on compaq evo pentium iv / , ghz computers with windows sp . after participants had intro- duced demographic information and understood the instructions, they went on to the actual experimental protocol. all stimuli were presented within a grey frame. in the upper segment of the frame there was a brief reminder of the task they were asked to perform. in the lower segment of the frame there was a reminder of the response scale they were required to use. based on previous studies that showed no effect of viewing time on aesthetic appreciation (mcwhinnie, ; smith, bousquet, chang, & smith, ), we decided not to impose a time limit on participants’ responses. hence, each stimulus was presented until participants responded. they did so by pressing a key between and in the phases and , and a key between and in phase . if participants pressed any other key there was no response from the program. if the response was within the appro- priate values it was fed-back on to the screen for . s, after which the -s masking screen appeared again. this same pattern was implemented for the , , and stimuli in the first, second, and third phases, respectively (see in / nadal et al. the procedure section). the computer program registered all the demographic information given by the participants and each of their responses to the stimuli in each phase. procedure in order to achieve the objectives outlined above, the present work was struc- tured into three phases. the first phase was designed to create a set of stimuli suitable to carry out both subsequent phases. the second phase consisted in the exploration of the relation between complexity and beauty appreciation by means of a beauty rating task using the set of stimuli created in the first phase. finally, the aim of the third phase was to address the three issues we specified with regards to the nature of visual complexity. phase : creating an adequate stimulus set our aim was to obtain a set of stimuli equally divided into three com- plexity levels: low, intermediate, and high. each of these complexity levels would include abstract artistic (aa), abstract non-artistic (an), representa- tional artistic (ra), and representational non-artistic (rn) stimuli. the participants recruited for phase were divided into eight different groups of individuals, attempting to balance each of them in relation to sex. the set of stimuli was divided into eight groups of , using a stratified randomized method, such that there were stimuli of each kind (aa, an, ra, rn) in each group. they were presented to all participants in the same random sequence. participants were asked to rate the complexity of each of the images on a to likert scale (very simple–very complex). at this stage complexity was not defined to participants. participants were only instructed to focus on their general impression of the visual complexity of each stimulus, not on the complexity involved in producing it. two statistics were calculated for each stimulus: the average rating awarded by the participants, considered as the complexity score, and the standard deviation, considered as the measure of participants’ agreement on that score. the selection of stimuli for each complexity level was based on both statistics, and was carried out separately for each of the stimuli types (aa, an, ra, rn) according to the following procedure. the stimuli in each of the four kinds of images were ordered according to their complexity score. to select stimuli for the low complexity level, the experimenter began at the bottom of the list of stimuli (those with the lowest complexity score). if the standard deviation for the first stimulus was below . , it was selected. if it was . or above, the stimulus was discarded and the operation was repeated with the stimulus immediately above in complexity score. this process was carried out for each of the four stimuli types until stimuli of each particular type had been selected. in order to select stimuli for the high complexity level the same procedure was followed, visual complexity and beauty / except that it began at the top of the list and moved down the complexity scores. again, this finished when stimuli of each kind had been selected. in order to select stimuli for the intermediate level of complexity, the median of the complexity scores was calculated for each stimulus kind. the experimenter started the selection at that point, using the same agreement criterion as mentioned above, only that he alternatively moved up and down the list to select or discard the stimuli. when the images of each kind had been selected, the process was ended. this procedure was followed with the objective of maximizing the difference between the three complexity levels and to minimize the difference in complexity within levels. choosing images whose complexity score had a small standard deviation was aimed at including stimuli for which people tended to agree on their degree of complexity. phase : beauty appreciation test the objective of this phase was to explore the influence of complexity, degree of abstraction, and artistry on beauty appreciation. the participants described above were asked to rate the beauty of the stimuli selected in the previous phase on a to (very ugly–very beautiful) likert scale. stimuli were randomized and presented in the same order to all participants, who were sat at different computers in the same room. the average rating awarded by participants was calculated for each stimulus. this was the dependent variable used in our analysis of the influence of the three independent variables: complexity (low, intermediate, high), abstraction (abstract and representational), and artistry (artistic and non-artistic). phase : the nature of visual complexity this phase was conceived to explore the influence of different features of visual stimuli on judgments of complexity, the relations between these features, and their relation with the appreciation of beauty. in order to do so we selected of the stimuli used in phase . this subset was constituted by including five stimuli from each of the four kinds in each level of complexity from the stimuli set. the median value of complexity was calculated for each of the subgroups. we included the stimuli corresponding to the median value and the two adjacent stimuli on both sides. based on our review of the literature on visual complexity and its influence on the appreciation of beauty, we selected seven features we believed could relate to different aspects of visual complexity. these dimensions were: unintel- ligibility of the elements (difficulty to identify the elements in the image), dis- organization (difficulty to organize the elements into a coherent scene, amount of elements, variety of elements, asymmetry, variety of colors, and three- dimensional appearance. / nadal et al. the same group of participants who served as subjects in phase took part in this third and last phase. in this case they were asked to rate each stimulus on a to likert scale for each of the seven aforementioned scales. all the stimuli in the subset were rated on each dimension separately. stimuli were presented in a different random order for each dimension. before rating the stimuli on each particular dimension, participants received written and verbal instructions and a brief definition. after all participants had finished the task, their ratings were collected. the average rating awarded on each dimension were calculated for each stimulus. results phase : creating an adequate stimulus set the descriptive statistics of the set of images, selected from the initial according to the criteria mentioned in the procedure section, are shown in table for each complexity level by abstraction and artistry. a series of kruskal-wallis tests were carried out to make sure that the set was well suited to use in subsequent phases. results showed that there were differences between complexity scores of stimuli included in the high, intermediate, and low complexity levels for each of the four stimuli kinds, for all abstract stimuli, all representational stimuli, all artistic stimuli, and all non-artistic stimuli, as well as for whole set taken together. all differences were highly significant, with the lowest statistic corresponding to the representational non-artistic subset (� = . , p < . ) and the highest to the whole set (� = . , p < . ). additional mann-whitney pairwise comparisons revealed that scores of stimuli visual complexity and beauty / table . descriptive statistics for the set of visual stimuli to be used in phases and artistry complexity level artistic non-artistic abstraction n m sd abstraction n m sd high intermediate low abs rep abs rep abs rep . . . . . . . . . . . . abs rep abs rep abs rep . . . . . . . . . . . . note: abstraction refers to abstract (abs) and representational (rep) images. included in the high complexity level were significantly greater than those in the other two levels, and that stimuli included in the intermediate level had been rated as more complex than those included in the low level. this is true for each of the stimuli categories and the whole set of stimuli taken together. in this case, the lowest statistic corresponded to the comparison between low and intermediate complexity levels of abstract images (z = . , p < . ) and the highest to the comparison between low and high complexity scores for the whole set of stimuli (z = . , p < . ). hence, the objective of the first phase of the investigation, the creation of a set of diverse visual stimuli grouped in three distinct levels of complexity, had been accomplished. phase : beauty appreciation test table shows the descriptive statistics for the beauty ratings to stimuli varying in complexity, abstraction, and artistry. given that homogeneity of variances could not be assumed, and that some of the distributions of beauty ratings could not be considered to approach normality, we used non-parametric techniques to test our hypotheses regarding the influence of complexity on beauty ratings awarded to visual stimuli varying in abstraction and artistry. our results show that our three independent variables had significant main effects on participants’ beauty ratings, revealing that they preferred high com- plexity stimuli over low complexity stimuli (z = . , p < . ), representational over abstract stimuli (z = . , p < . ), and artistic over non-artistic stimuli (z = . , p < . ). however, these results must be viewed in light of the triple / nadal et al. table . descriptive statistics for participants’ beauty scores awarded to each kind of stimulus artistry complexity level artistic non-artistic abstraction n m sd abstraction n m sd high intermediate low abs rep abs rep abs rep . . . . . . . . . . . . abs rep abs rep abs rep . . . . . . . . . . . . note: abstraction refers to abstract (abs) and representational (rep) images. artistry refers to artistic and non-artistic images. interactions we identified, specifically the effects of complexity within each abstraction by artistry level. interaction analysis revealed that complexity had significant effects on participants’ beauty ratings only of representational non- artistic images (� = . , p < . ). scores were higher for high complexity representational non-artistic stimuli than for low complexity images of the same kind (z = . , p < . ). phase : the nature of visual complexity the first issue we explored in relation to complexity was the possibility that participants relied on different features when judging the complexity of different kinds of visual stimuli. in order to do so we performed a series of discriminant analyses, which allow determining the best combination of independent variables (complexity dimensions) to predict the level of complexity (low, intermediate, high) of diverse kinds of stimuli (aa, an, ra, rn). table shows the results of these analyses. it is interesting to note that for most stimuli kinds only one or two complexity dimensions were required to accurately predict the complexity level of the stimuli. furthermore, remarkably high levels of explained variance, correct classification, and agreement between predicted and actual complexity level were achieved. from the results presented in table , it seems that dimension (amount of elements) is the best overall predictor for general complexity ratings. conversely, dimensions , , and (disorganization, variety of elements, and variety of colors), were of little relevance to predict complexity level. visual complexity and beauty / table . results for the discriminant analyses carried out on participants’ ratings of each kind of stimulus stimuli pd ev (%) cc (%) kappa abstract artistic abstract non-artistic representational artistic representational non-artistic & , , & . . . . . note: pd: predictive dimensions; ev: explained variance; cc: correct classification. kappa: agreement between actual and predicted complexity level based on predictive dimensions. all kappa values are significant at p < . . with regards to kind of stimuli, results showed that dimension (amount of elements) was a sufficiently adequate predictor of complexity ratings of both abstract and representational non-artistic stimuli. the prediction of complexity level of artistic images required including other aspects. in addition to dimension , discriminant analysis revealed the importance of dimension (unintelligibility of the elements) when rating the complexity of abstract artistic stimuli, and of dimensions (asymmetry) and (three-dimensional appearance) when rating the complexity of representational artistic stimuli. the second issue we explored in relation to the concept of complexity was whether there was any relation among the seven dimensions of complexity we had considered. this was done by means of factor analysis. sedimentation tests recommended the extraction of three factors for participants’ ratings. although the third eigenvalue was below (. ), we decided to maintain the recommendation of the sedimentation test, given that dimension (asymmetry) only loaded satisfactorily on this third factor. we believe this decision is justified by the historical relevance of symmetry in the study of the relation between complexity and the appreciation of beauty, and the fact that eigenvalues of the additional four factors were well below . table shows the initial eigenvalues for the seven components, as well as the percentage of variance explained by each of the three extracted factors, together with rotated extracted values. the first extracted factor explained close to % of the variance, the second factor explained about %, and the third factor explained approximately . %. overall, the three factors accounted for over % of the variance in participants’ ratings. table shows the rotated component matrix. / nadal et al. table . results for the factor analysis carried out on participants’ scores on the seven complexity dimensions, including initial eigenvalues and percentage of explained variance before rotation, and rotated extracted factors initial eigenvalues rotation sums of squared loadings factor total % of variance cumulative % total % of variance cumulative % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . after the rotation it became very clear that the first factor received loadings mainly from dimensions (amount of elements), (variety of elements), (variety of colors), and to a lesser degree, (three-dimensional appearance), while saturations from other dimensions were negligible. dimensions (unintel- ligibility of the elements) and (disorganization) showed high loadings on the second factor, whereas dimension had a low positive loading and dimen- sion a moderate negative loading on this factor. finally, only dimension (asymmetry) loaded heavily on the third factor. the final issue we wished to clarify in relation to complexity was the possi- bility that different forms of complexity influenced beauty appreciation in diverse ways. given that the present study was not designed expressly to test this possibility experimentally, our approach is merely exploratory in nature. we performed a curve fit test for each of the three complexity factors identified above and the beauty scores awarded by men and women. the factor scores corresponding to each stimulus were entered as independent variables and the beauty scores as dependent variables and calculated the fit to linear, quadratic, and cubic functions. if more than one function, or none, produced a significant fit, we chose the one with a lower significance level. if significance was equal, we chose the one with the greater r value. the relation between factor and beauty scores fit a cubic function (f = . , p < . ). the relation between factor and beauty scores fit a quadratic function (f = . , p < . ). finally, the best fit of the relation between factor and scores was to a quadratic function, though non-significantly (f = . , p = . ). these results are shown graphically in figure . there are clear differences among the relations between the three complexity factors and beauty ratings. ratings of beauty increased linearly with complexity factor , it had a descending u-shaped relation with complexity visual complexity and beauty / table . rotated component matrix factor dimension . –. . . –. . . . . . . –. –. –. –. –. –. . . . –. / nadal et al. figure . results for the curve fit between the three complexity factors and beauty scores. factor , and, finally, both variables showed an inverted u-shaped relation, whereby maximum beauty scores corresponded to intermediate levels of com- plexity factor . discussion the influence of complexity on beauty appreciation our results showed that complexity had a negligible effect on beauty ratings of most of our stimuli kinds. in fact, it turned out to influence only the beauty ratings of representational non-artistic images. specifically, participants awarded higher beauty ratings to high complexity images of this kind than to the low complexity ones. this might seem to suggest that the effects of complexity on beauty ratings are modulated by the kind of stimuli, which would support one of our initial explanations for the divergence of results among earlier studies. however, an alternative explanation for the effect of complexity observed for this kind of stimuli arises from the careful examination of the data and the stimuli themselves. participants rated highly complex representational non- artistic stimuli as beautiful as artistic representational stimuli belonging to any complexity level. conversely, their beauty ratings of low complexity represen- tational non-artistic stimuli were similar to those awarded to most abstract non- artistic stimuli, independently of their complexity. the comparison of low com- plexity and high complexity representational non-artistic stimuli reveals an unforeseen yet clear difference between both groups of stimuli. representational non-artistic stimuli that were included in the level of low complexity are simple or schematic drawings or photographs of individual objects, such as a car, a biker, bananas, a pencil, and so on. conversely, representational non-artistic stimuli assigned to the high complexity level are, for the most part, paintings or photographs of natural sceneries, such as landscapes or seascapes. hence, it seems that the beauty ratings awarded by our participants without artistic training reflect a tendency to consider the art-looking postcards or illustrations as artistic and to reject simple depictions of individual objects. this suggests that our category of non-artistic stimuli could probably be subdivided into a category of what lindauer ( ) and winston and cupchik ( ) might consider cheap or popular art and a category of what we could call icons or objects. the concept of visual complexity since berlyne and colleagues’ ( ) initial distinction among complexity forms, such as the amount of elements, their heterogeneity, the irregularity of their shapes, the irregularity of their disposition, the degree with which the different elements are perceived as a unit, asymmetry, or incongruence, there has not been much work aimed at determining whether these features impact visual complexity and beauty / perceived complexity in the same way and to the same extent. in addition, there has been little research on the relation among the complexity features themselves. finally, there has been no attempt at determining whether different complexity features affect beauty appreciation in the same way or to the same extent. most research in empirical aesthetics and visual perception has regarded complexity as a one-dimensional concept. although many studies have dealt with the relation between complexity and the appreciation of beauty, their conception of com- plexity has not always emphasized the same aspect. whereas some studies have conceived complexity as the amount of elements in a stimulus—lines, angles, turns, and so on—others have regarded it as the degree of asymmetry, or the degree of incongruity. this obviously creates problems when comparing their results, which may differ precisely because complexity refers to different aspects in different cases. the results of our analyses revealed that the complexity level of each kind of visual stimuli could be predicted very reliably from solely one or two dimensions. importantly, not all aspects of an image are taken into account by participants to the same extent when asked to rate its visual complexity. overall, and in agreement with berlyne and colleagues’ ( ) results, participants’ ratings of visual complexity seem to be driven mostly by the amount of elements. con- versely, disorganization, variety of elements, and the variety of their colors seem to have little influence on people’s impression of visual complexity. this is in agreement with hall’s ( ) results, which suggested that the variety of colors did not represent an important factor when rating the complexity of linear stimuli. an interesting finding is that the artistic status of the stimuli influenced visual complexity ratings. whereas the amount of elements seems to be the most relevant feature when people express their impression of the complexity of non- artistic stimuli, additional aspects appear to be taken into account when rating the complexity of artistic stimuli. these include unintelligibility of the elements in the case of abstract artistic images and asymmetry and three-dimensional appearance in the case of representational artistic images. these exploratory results suggest hypotheses that require future experimental testing under rigorously controlled conditions and with stimuli specifically manipulated to this end. regarding the relation among the seven complexity dimensions, our results indicated the existence of two factors that explained most of the variance, and a third one which we included to account for asymmetry. the first factor received high loadings from the following dimensions: amount of elements, element heterogeneity, variety of colours, and three-dimensional appearance. the second factor received high loadings from unintelligibility of the elements and disorgani- zation. and the third factor, as we just mentioned, received high loadings only from asymmetry. these three factors could be referred to as elements—which has to do with the amount and variety of the elements, organization—related with how the elements are grouped to form identifiable objects and how these are organized into a coherent scene, and asymmetry. / nadal et al. generally speaking, these results are in line with prior studies. berlyne and colleagues’ ( ) factor analysis indicated the existence of two main factors, one related with the amount of elements and another which was a composite of several dimensions, and named it unity versus articulation into easily recognizable parts. it stands out that these two factors are very similar, or even equivalent, to our elements and organization factors. however, whereas our elements factor accounted for just under half of the variance in complexity ratings, berlyne and colleagues ( ) found that it accounted for between % and % of the variance. this difference in the relevance of the amount of elements on complexity ratings might be due to the fact that the stimuli used by berlyne and colleagues were simple line drawings in which the constituting elements were much more salient that in most of the stimuli used in the present study. other studies have also found participants’ impression of complexity to depend on two kinds of features. nicki and moss ( ) suggested that there might be two kinds of complexity factors, a “perceptual” one related with the number and variety of elements, and a “cognitive” one related with the amount of asso- ciations or cognitive tags elicited by stimuli. chipman ( ) distinguished between a qualitative component of complexity judgments, determined largely by the amount of elements, and a structural component, related with symmetry, the repetition of motifs and other organizational processes. chipman noted that the first factor, related to the amount of elements, seems to set an upper threshold of perceived complexity and the second one can act to reduce this impression, a suggestion that was later experimentally corroborated by ichikawa ( ). thus, our results add further support to the idea that two or three processes contribute to the formation of subjective visual complexity. probably the most important one is the determination of the number and variety of elements. the second one refers to how well the elements organize into a coherent scene. although previous studies have subsumed asymmetry within organizational processes, the present results showed this was not an adequate solution for our data, and hence, we chose to include it as a separate factor. the temporal sequence of cognitive processes related with these factors remains to be elucidated, though based on ichikawa’s ( ) results, a plausible hypotheses is that the different features are processed in parallel, but that operations related with elements are faster than those related with organization, which are completed later. the final part of this study was a tentative exploration of the possibility that the different factors of complexity are related in different ways to beauty ratings. this can only be regarded as a very tentative exploration because stimuli were not designed to vary independently on each of the complexity factors. despite this limitation, our results suggest that complexity factors might influence beauty appreciation in very different ways. the organization factor seemed to have a u-shaped or descending relation to beauty. specifically, stimuli receiving extremely low values on this factor were rated as more beautiful than those receiving intermediate and high scores. in contrast, the second factor, elements, visual complexity and beauty / had a positive relation with beauty: high-scoring images, those with a large amount and variety of elements, were those that had obtained the best beauty ratings. finally, our results suggest that the last factor, symmetry, seems to have an inverted u-shaped relation to beauty: images rated as intermediately asym- metric were considered to be more beautiful than those rated as extremely asymmetric or extremely symmetric. our review of the literature supports the possibility that the diversity of relations between complexity and beauty that have been found in previous studies were due to their emphasis on different complexity factors. based on our results, we would expect those studies that have varied complexity by manipulating the amount or diversity of elements to have found an increasing relation between complexity and beauty ratings. we would expect to find that studies manipulating complexity by means of organizational features obtained decreasing or u-like distributions between complexity and beauty ratings. finally, we would expect prior studies that specified complexity along a symmetry-asymmetry dimension to have produced the expected inverted-u distribution of beauty ratings over complexity. we used prior studies to test this retrospective prediction. we only selected those that utilized some sort of specific complexity measure, leaving out those that assessed complexity by means of a general complexity rating scale. six studies had designed or employed stimuli which varied along the elements factor (aitken, ; day, ; heath et al., ; nicki, ; nicki & moss, ; stamps, ), five had designed or used stimuli which varied along the organization factor (krupinski & locher, ; neperud & marschalek, ; nicki et al., ; nicki & moss, ; osborne & farley, ), one had used stimuli varying only in asymmetry (krupinski & locher, ), three had used stimuli which varied in asymmetry as well as elements (eisenman, ; imamoglu, ; munsinger & kessen, ), and one had used stimuli varying in all three factors (francès, ), which was discarded due to its combined use of measures related with the three factors. we also pooled the studies that had conceived complexity as asymmetry or the combination of asymmetry and number of elements into a single category. for each of the studies, we summarized its main conclusion as supporting an increasing, inverted u-shaped, or decreasing/u-shaped, relation of awarded beauty scores and complexity. table shows the cross-tabulation of the main factors manipu- lated by these studies and the shape of the relation between complexity and beauty appreciation. the results of the chi-square test are highly significant (� = . , p < . ). directional measures were calculated in order to assess the strength of the association. they revealed that there is a strong relation between the way in which previous studies have specified complexity and their resulting distribution of beauty scores as a function of complexity. moreover, as the measures of association show, the kind of distribution can be predicted from the complexity factor manipulated by the experimenter with a considerable degree of accuracy / nadal et al. 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( ). the evaluation of high art and popular art by naive and experienced viewers. visual arts research, , - . direct reprint requests to: marcos nadal department of psychology university of the balearic islands crta valldemossa s/n, km , palma de mallorca balearic islands, spain e-mail: marcos.nadal@uib.es visual complexity and beauty / love, beauty, and yeats's "anne gregory" ocad university open research repository fa c u l t y of libe r a l arts & sci e n c e s love, be a u t y , an d yeat s ' s "ann e gr e g o r y " bick n e l l, jea n e t t e s u g g e s t e d ci t a t i o n : bick n e ll , jea n e t t e ( ) love, be a u t y , an d yeat s ' s "ann e gr e g o r y " . philos o p h y an d lite r a t u r e , ( ). pp. - . iss n - x availa bl e at htt p : // o p e n r e s e a r c h . o c a d u . c a / i d / e p r i n t / / op e n re s e a r c h is a pu b li cl y acc e s s i b l e , cur a t e d re p o s i t o r y for th e pre s e r v a t i o n and diss e m i n a t i o n of sch ol a rl y and cre a t i v e out p u t of th e ocad uni v e r s i t y co m m u n i t y . ma t e r i al in op e n r es e a r c h is op e n acc e s s and m a d e availa bl e via th e con s e n t of th e aut h o r and/ o r rig h t s hol d e r on a no n- ex cl u s i v e basi s. love, beauty, and yeats's "anne gregory" jeanette bicknell philosophy and literature, volume , number , october , pp. - (article) published by johns hopkins university press doi: for additional information about this article access provided by ontario college of art & design (ocad) ( feb : gmt) https://doi.org/ . /phl. . https://muse.jhu.edu/article/ https://doi.org/ . /phl. . https://muse.jhu.edu/article/ philosophy and literature, © , : – jeanette bicknell love, beauty, and yeats’s “anne gregory” never shall a young man, thrown into despair by those great honey-coloured ramparts at your ear, love you for yourself alone and not your yellow hair. so begins “for anne gregory,” published by w. b. yeats in . it is surely one of his most charming poems. the poem’s lilting rhythm and affectionate tone effectively soften—even disguise—what is arguably a dark and dismaying message. anne is destined to be loved not for herself alone, but for an accidental physical attribute—her blond hair. why do i claim that the poem’s message is dark? why should it dismay anne if she is loved for the beauty of her hair? is that not better, after all, than not being loved in the first place? and what would it be to love anne for herself “alone”? love anne for her sweet disposition; for her ability always to say the right thing; for her kindness; but for her yellow hair? reflections on these questions take us to the heart of some of the most crucial philosophical problems of romantic love. can one draw a neat line between rational and irrational (or at least, non-rational) motives for loving another, or for pursuing love? we might call this question the “anne gregory problem.” in the western tradition the origins of philosophical reflections on love, as of so many other things, can be traced to the works of plato. the account of love offered in the symposium is hierarchical, taking the form of a ladder. the love of the beauty of a particular boy is but a first step that is to be ultimately transcended by a love of beauty itself. interpreters disagree as to whether love for that first individual is cast jeanette bicknell aside in the ascent up the ladder, or whether it is more correctly the intensity of the lover’s initial passion for a particular individual that must be transcended. whatever the outcome of this question, it may strike us as bizarre that the love of a particular individual is seen as an inferior stage that must be surpassed. what is love, if not love for concrete others? there is something unseemly about considering one’s beloved or oneself as steps on a ladder of philosophical fulfillment. yet the vision of love offered in yeats’s poem, in which the love of an indi- vidual is seen as secondary to a love of one of her physical attributes, should strike us as equally unsatisfactory. platonists or not, we seem to have conflicting intuitions about love and rationality. on the one hand, love is considered non-rational because it is not subject to volitional control. cupid is often depicted as blindfolded, so that his arrows fall where they may with little regard to the appropriateness of their targets. we love some people and not others, and that is all there is to it. imagine hearing a single friend describe a meeting with a potential romantic partner; he recounts the many good qualities of the person he has met, yet concludes that he has no wish to pursue a relationship or see that person again. even if our friend cannot offer a reasoned justification of his reluctance, we would not conclude that he is behaving irrationally. other things being equal, we would probably accept both his assessment of the meeting and his decision not to seek further involvement. the non-rationality of love is even more evident in the case of familial love. parents love their children simply because they are their children. they do not love the children because of specific qualities the children possess, although the character and quality of parental love may be responsive to such qualities. harry frankfurt has offered the most robust philosophical defense of the view that love is non-rational. on the other hand, we also seem to think that love (and the with- holding of love) can be responsive to reasons. philosophically, this type of view is associated with david velleman and niko kolodny. reasons for love may be grounded in the qualities of the beloved or of a shared relationship. for many months in , one of the most emailed articles from the new york times website was a list of questions that couples were advised to ask one another before agreeing to marry. the questions very reasonably covered such practicalities as expectations about children and social roles within the marriage, and also about attitudes to financial matters and sexuality. clearly many believe that rationality has a role (or should have a role) in romantic love. we wonder why put-upon philosophy and literature or abused spouses continue to stay with their partners, reflecting that they have perfectly good reasons to end such relationships. familial love seems no less amenable to reasons. we expect familial love to take hold and endure, except in the face of overwhelming reasons why it should not. parents who fail to bond with or seem indifferent to their children’s well-being seem strange, if not contemptible. is the parent- child connection itself not reason enough for love? there is room for a different response to the “anne gregory problem.” i shall argue that rationality can have a place here, but not in the way one might expect. recent philosophical reflections on love and rational- ity share a crucial oversight. in focusing on the rationality of lovers they have overlooked the beloved. whether or not loving someone admits of reasons, and whatever the nature of these reasons, the lover is only one of the possibly rational agents. we can also assess the rationality of the beloved, and the reasons he or she might have for accepting or resisting love. the rationality of love can be assessed in terms of what it is reasonable or appropriate to be loved for. someone who is content to be loved for the yellowness of her hair, and who expects this love to form the foundation of a reciprocal relationship, is not rational. i yeats’s poem ends on a playful note, at once reinforcing and under- cutting anne’s anxieties about the source of her lovability. the poet gives himself the last word, while doubly removing himself from the responsibility for those words: i heard an old religious man but yesternight declare that he had found a text to prove that only god, my dear, could love you for yourself alone and not your yellow hair. the upshot of the final stanza is that it is humanly impossible to love anne for herself and not for her blonde hair. to do so would require a superhuman effort. perhaps the poet—in invoking the old religious man and the text—means us to take the reply as humorous. perhaps he means to make anne smile and set her at ease. one philosopher— amelie oksenberg rorty claims that the poet’s reply to anne, although jeanette bicknell sad, is sage and truthful (p. ). this assessment is of a piece with her skeptical attitude to the possibility of offering general philosophical reasons for loving another. although reasons may be given, they can only be particular and relational, not abstract or general (and hence not philosophical). according to rorty love is individuated by the character of the subject who loves, the object that is loved, and the relation between them, and it shares these features with a number of other psychological attitudes. one’s love for a spouse is not the same as the love one feels towards one’s parents or children, yet “love” may be the correct term for the feeling in each case. love, together with a number of other psychologi- cal attitudes, share a feature which rorty calls their “historicity.” what she means is that these attitudes are not static; they arise from and then are shaped by dynamic interactions between the subject and object. the love one person has for another is the product of a distinctive, and in some cases on-going, dynamic interaction. the beliefs and behaviour of the beloved arouse beliefs and behaviour in the lover. dynamic, interac- tive and historical psychological attitudes have a number of features in common. they take as their proper objects persons, rather than charac- teristics of persons. they are “permeable”—both the subject’s character and actions may be changed by details of the character of the beloved. finally, these attitudes have a specific narrative history. the historicity of love allows it to be sensitive to changes in the characters and situations of the individuals involved, but it also arouses worries about love’s constancy. a love that is dynamic and responsive to changes in the object is also a love that can turn to indifference or worse, depending on changes in the object. rorty interprets the desire of anne in yeats’s poem to be loved “for herself alone” as an expression of anxiety about love’s constancy or endurance. she sees such concern about love to be a recent historical phenomenon that has arisen in a specific cultural context, and claims that there are two reasons why contemporary lovers are so concerned with love’s constancy. first, we feel ourselves to be vulnerable in the world. second, we are aware of being constituted by the perceptions of others. if others—especially those closest to us—fail to perceive us aright and fail to be sensitive to changes we might undergo—this may have adverse consequences for our self-image and well-being. rorty concedes that love and the other psychological attitudes which share the quality of historicity may be sometimes voluntary and inten- tional; however she resists classifying them as voluntary or responsible philosophy and literature actions. “interactive attitudes,” she writes, “are not necessarily caused by intentions or under voluntary control” (p. ). moreover, the historicity of these attitudes does not threaten their possible rationality. indeed, because of the connections among rationality, human thriving, and the possible corrigibility of our psychological attitudes, it is worth thinking about the possible role for rationality in love. but there is a problem here: the lovers must perceive one another accurately, and their “attun- ement” to one another must be appropriate. yet what conduces to the continuity of their love might not serve either of the lovers as individuals. furthermore, whatever contributes to the development and thriving of one of the lovers might not contribute to the harmony between the two of them. all of these depend on factors that are specific or tied to the historicity of each particular relationship. so there is a limit to what we can say in general philosophical terms about love and rationality. as rorty herself puts it, “it is only the details of their particular situation that can determine what would be rational, what would be appropriate, what would constitute (whose?) thriving” (p. ). is rorty’s skepticism here justified? while it seems correct that love has a historicity in something like the way she describes it, does it really follow that little can be said in general terms about love, rationality, and thriving? rorty seems to be led to her skeptical view by the decision, at the outset, not to classify love together with voluntary and responsible actions. in doing so, she risks collapsing a distinction between desire, which may be completely one-sided and unrequited, and the love which forms the foundation of a loving relationship. (and it seems clear that rorty’s concern is with this kind of love, rather than with desire alone, since her examples in the article are of love within continuing relationships.) while desires may be involuntary and may overcome us without our consent, romantic love is at least in part elective. this is not to say that we can choose whom we love, anymore that we can choose to believe in god. but (as pascal realized long ago) religious feelings can be encouraged or depressed by one’s actions; feelings of love and desire are similarly subject to behavioral modification. love need not be pursued. romantic relationships can be initiated or ended at either individual’s whim. most people do not pursue every person whom they desire—practicality, time and existing commitments being only some of the likely constraints. jeanette bicknell ii d. w. hamlyn, another philosopher to address the “anne gregory problem,” defends an equally cautious, though less skeptical position. hamlyn considers the limits of the intelligibility of the terms “love” and “hate” where beliefs about their objects are missing, and frames the question thus: “if one does love x, what beliefs must one have about x, and how must one see or regard x if it is really to be love?” he answers that love (and hate) can be considered rational and justified when their objects have certain appropriate qualities. yet if such qualities are lacking, it does not necessarily follow that the love or hate is irrational, even if we might want to say that it is non-rational. loving someone is compatible with having no respect for him, finding him distasteful, or recognizing in him significant character flaws. hamlyn concludes that there is no particular belief that the lover must have about the object of love. however while such beliefs are not a necessary requirement for love, it would be “odd” if love and hate always lacked appropriate beliefs. human love and hate could not universally be like that. so love must, in general, make some place for rationality, even if we cannot say exactly what that place is. what hamlyn says about the rationality of love seems correct, but misplaced. whether or not a lover has adequate and appropriate beliefs about the beloved is only part of the story. hamlyn’s “epistemology” of love is one-sided and thus inadequate. we see this clearly when we turn to the beloved; in this case to anne. iii we know that anne finds the poet’s claim that she will not be loved for herself “alone” to be troubling because of her reply to him, which comprises the second stanza: but i can get a hair-dye and set such colour there, brown, or black, or carrot, that young men in despair may love me for myself alone and not my yellow hair. philosophy and literature the philosophers who have discussed or alluded to yeats’s poem are mostly concerned with the first and third stanzas and pay little heed to the second. this is unfortunate. if the second stanza is ignored or (as hamlyn does) paraphrased hastily then anne is rendered as mute and anonymous as the beautiful boys who are the initial objects of love on plato’s ladder in the symposium. as many have argued, the notion of reciprocity and relatedness are crucial to romantic love, and indeed to many human interactions. romantic love for another person, as distinguished from unexpressed yearning or longing or from love for a person’s memory, is intrinsically dialogic. yeats acknowledges this in giving anne a voice. there are several reasons why anne might find the poet’s words dis- maying. first, there is the matter of exclusivity as opposed to fungiblity. anne might reasonably expect that if her young man loves her truly he will be willing to forsake others. she probably also wants to feel that she is special in the regard of the young man; she does not want to feel that she could be the substitute for another woman, or that another woman could be readily substituted for her. but if what the young man loves in anne is her blond hair, will he also love this property when it is manifested in any other woman? that is, is anne loved merely as an exemplar of a blond woman—is she loved simply qua blond woman rather than qua anne—and might her young man thus love any and every blond woman he encounters? might he even be rationally con- strained to do so? yet the poet’s words are more careful (and more crafty) than i have suggested thus far. it is anne who is loved; not her hair. thus the distinc- tions among loving universals, loving particular properties, and loving properties as manifested in specific individuals, need not concern us very much. the opening stanza presented the reader with a paradox. anne is loved, but she is loved for a feature that she and others might regard as accidental, incidental, and trivial. nonetheless she is truly loved, or so the poet claims. is anne truly loved if she is loved simply for her beauti- ful hair, and not for herself ? typically we demand of romantic love, if it is true love, that it be for the whole person, the whole self. the proper object of love is seen to be persons, not their physical manifestations, and certainly not their hair. this issue of the proper object of love is closely connected with the ideal of love’s durability or longevity. we want love to endure, and physical beauty (and hair color) are transitory. in the words of another poet, “but beauty vanishes, beauty passes; / however rare—rare it be.” most human beings, men and women, outlive the jeanette bicknell period of their greatest physical attractiveness. persons or selves are the proper objects of love, partly because these are thought to endure, setting aside brain-transplant operations, episodes of the fugue, and other traumatic breaks. to be loved for beauty alone is to be doomed to be unloved when that beauty passes. that is another reason why the poet’s words to anne are so dark and so troubling. yet so far we have not reached the crux of the matter both as to why anne is dismayed and why it is rational that she be dismayed. there is another reason, aside from their relative durability, why selves are the proper object of love, and not just of romantic love. this has to do with personal identity. in a tradition that begins with david hume and adam smith in the eighteenth century, continues with george herbert mead, and influences the work of contemporary feminists and others, the self is seen as at least partly constituted by others, and by our rela- tions with others. we can say this without also making metaphysically dubious claims to the effect that the lover and the beloved are united to form a “super entity,” a worry expressed cogently by deborah brown. for better or worse, our selves are constituted by the many relations we enter into on a daily basis, loving and otherwise. part of the “work” of any loving relationship—be it between romantic partners, friends, or parents and children—is the reinforcement of one another’s personal identities. this is true both of the particular roles that each of us plays every day and of our more general sense of persisting as a person in the world. this mutual identity-constitution takes place among family members, intimates, casual acquaintances and strangers hundreds of times a day. many of these interactions will be quickly forgotten, yet others will have profound and lingering effects. if young men love anne for her blond hair, there is a possibility that they relate to her not as a full person, but merely as an exemplar of a blond woman. if this is so then we can imagine deleterious consequences for anne’s identity—her image of herself as reflected back to her by others. anne may realize that she has beautiful hair. she may even be proud of her hair. but it does not follow that her hair is the cornerstone of her identity, or that she should want others to relate to her as though it was. anne, clearly, does want to be loved for her self alone and not for her hair. she regards her hair color as inessential to who she is; it is something easily changed. her words express the anxiety of a beautiful woman who is perhaps wary of her own beauty. she is willing to alter what others regard as her most beautiful feature in order that they not love her on account of this feature, but for what she regards as her philosophy and literature essential self. anne’s assertion of control over her hair color is also an expression of desire to control how others see her. in controlling the image that others have of her, she seeks to have them reinforce those aspects of her personal identity that are more salient to her than the color of her hair. we already know, from the poem’s final stanza, that any attempts anne might make in this direction would be futile. while she might have control over her hair, she has at best limited control over others’ desire. it would be unproblematic for us and for anne if she was desired for her blond hair; difficulties arise because the poet tells her she is loved for it. can the love of a person’s physical attributes be so strong as to eclipse love of the self “alone”? the poet is clear that anne is loved; but she is loved for her beautiful hair. are we to accept that beauty can be so alluring as to arouse love, in addition to desire? alexander nehemas has argued that to love someone is to find him or her beautiful. while this may be true surely the contrary need not hold. to find someone beautiful is not necessarily to love him or her. perhaps the besotted young man will be disappointed when he gets to know anne. perhaps he will not like her very much in the end. so why is the poet so confident that anne is truly loved? the answer is obvious, but easily overlooked. he knows anne, even if we do not. he knows all about her lovable qualities. that is why he can be so confident that others will love her too. must we believe the poet? perhaps he has simply collapsed the differ- ence between love and desire. perhaps he tells anne that she is loved, concealing (out of propriety?) his actual belief that the young men lust for her because of her hair. indeed the phrase “young men in despair” suggests thwarted desire. love and desire are often contrasted with one another. desire may be unruly and wildly particular; we hold it account- able to few rules. it may be completely one-sided and unrequited. a person need not even ever know that he or she is an object of desire. there is nothing wrong or mistaken in the desires of a person who is especially attracted by those with blond hair, or any specific color hair. the person who is attracted only to blondes does not do some kind of injustice to brunettes and redheads. we accept the particularity of desire. rightly or wrongly, we seem to take a different attitude to love, setting aside the accepted and occasionally irrational love of parents for their children. i believe that we should resist this suggestion that anne is desired rather than loved and accept at face value the words of the poet that she is loved. if anne is merely desired on account of jeanette bicknell her beautiful hair then there is no problem to be addressed, and the poem can no longer be appreciated for its exquisite balance between a dark content and the sunny expression that alleviates it. i have stressed the ways in which lovers constitute and reinforce one another’s identity, and the corresponding importance of allowing one- self to be loved for qualities that one regards as properly pertaining to one’s self “alone.” this is not just a matter of what rorty discusses as the importance of correct perception attunement between lovers, and what hamlyn calls correct beliefs about the object of love. the rationality of love is not just a matter of deciding what is or is not truly loveable or of “drawing a line” between rationality and irrationality. it is also about allowing oneself to be loved for certain qualities, and thus allowing oneself to be constituted by others in certain ways. but which qualities and in which ways? is there anything general philosophical to be said here, or must we be satisfied with rorty’s particularism? although it is tricky, we can respect the historicity of each loving relationship and still say something of general import. the key here is agency. an important part of the kind of love that forms the basis of committed relationships is the desire for reciprocity. we want those we love to love us in return. this is ordinarily true of both familial love and romantic love. reciprocity requires agency. in allowing ourselves to be constituted by others, we must resist those who would constitute us in ways that are not conducive to the formation and continuation of reciprocal relationships. loving anne for her beauty might be something like lov- ing her as an art object. such an attitude would hardly be conducive to reciprocity because it denies the loved one agency. we can love artworks and other beautiful objects, but they do not love us back. desire may be non-volitional; we may not be able to choose whom we are attracted or who is attracted to us. but the love that is intrinsic to human flourishing is typically held to more stringent standards of rationality. it may not be irrational to love anne for her yellow hair. one may not have a choice in the matter. but it would be irrational for anne to allow her lovers to relate to her in such a way that her identity is constituted as being lovable for the color of her hair. ontario college of art and design, toronto philosophy and literature i am grateful to alice maclachlan and ian jarvie for comments and suggestions. . i will refer to the main speaker of the poem as “the poet” to distinguish him from yeats, the author of the poem, and i will refer to the woman addressed in the poem as “anne,” to distinguish her from the historical anne gregory. . i have benefited from reading and thinking about the following philosophical dis- cussions of love: deborah brown, “the right method of boy-loving,” in love, analyzed, ed. roger e. lamb (boulder: westview press, ), pp. – ; ronald de sousa, “the rationality of emotions,” in explaining emotions, ed. amelie rorty (berkeley: university of california press, ), pp. – ; harry g. frankfurt, the reasons of love (princeton: princeton university press, ); d. w. hamlyn, “the phenomena of love and hate,” philosophy ( ): – ; niko kolodny, “love as valuing a relationship,” philosophical review ( ): – ; rebecca kukla, “holding the body of another,” symposium ( ): – ; roger e. lamb, “love and rationality,” in love, analyzed, pp. – ; alexander nehemas, “‘only in the contemplation of beauty is human life worth living’ plato, symposium d,” european journal of philosophy ( ): – ; martha nussbaum, “love and the individual: romantic rightness and platonic aspiration,” in love, analyzed, pp. – ; amelie oksenberg rorty, “the historicity of psychological attitudes: love is not love which alters not when it alteration finds,” midwest studies in philosophy ( ): – ; laurence thomas, “reasons for loving,” in the philosophy of (erotic) love, ed. robert c. solomon and kathleen m. higgins (laurence: university press of kansas, ), pp. – ; and j. david velleman, “love as a moral emotion,” ethics ( ): – . . compare nehemas on this point with gregory vlastos, “the individual as an object of love in plato,” platonic studies (princeton: princeton university press, ), pp. – . . rorty finds the issue of exclusivity to be anne’s main worry. see de sousa for a discussion of love and fungibility. . for extended discussion of the general issues, see brown, nussbaum, and lamb. . walter de la mare, “an epitaph.” . for example, laurence thomas has written powerfully about how those in socially marginalized groups may be downwardly constructed by others. see “moral deference,” philosophical forum ( – ): – . . a similar anxiety is expressed in yeats’s “a prayer for my daughter”: “may she be granted beauty and yet not / beauty to make a stranger’s eye distraught / or hers before a looking-glass.” preface beautiful hypothesis and an ugly little fact ken-ichi honma editor-in-chief hokkaido university graduate school of medicine, sapporo, japan twelve years have already passed since sleep and biological rhythms (sbr) was launched. fortunately, the number of submissions to sbr has rapidly increased in the past several years. we have received a number of good manuscripts, far more than we have been able to publish. for example, last year ( ) manuscripts were submitted from coun- tries. the most submissions came from japan ( ), turkey ( ) and china ( ). since sbr is an official journal not only of the japanese society of sleep research, but also of the asian sleep research society, these figures are reasonable and expectable. furthermore, in we published six review articles, original articles, four short papers, three case reports, two letters to the editor and one editorial. the acceptance rate is approximately %. the -year impact factor was . in . recently, we decided to increase the number of sbr pages from to per year with the aim of publishing more manuscripts. sbr emphasizes the periodical aspect of sleep as implied by the name of the journal. to understand sleep, we should regard it not as a single physiological event, but as a sequence of events, namely sleep and wakefulness. sleep is affected by the preceding wakefulness and succeeding wakefulness is influenced by the preceding sleep. on the other hand, a sleep and wakefulness cycle in mammals is well known to be controlled by the circadian pacemaker located in the hypothalamic suprachiasmatic nucleus. it was more than years ago that the sleep and wakefulness cycle was found to spontaneously desynchronize from the circa- dian body temperature rhythm, suggesting at least two different oscillation mechanisms in humans (aschoff, ). under internal desynchronization, the sleep-wake cycle showed either a shorter (approximately h) or longer (approximately h) periodicity than the circadian temperature rhythm ( . h). several mechanisms have been proposed to explain internal desynchronization. among them, the most beautiful hypothesis was formally proposed some years ago, called the two process model (daan et al. ). the hypothesis assumes two processes: a self-sustained circadian process and an hour-glass pro- cess, which is processed by something increasing monoto- nously during wakefulness and declining exponentially during sleep. the hour-glass process is often called a homeostatic process. but in my opinion, the other terminol- ogy may lead to misunderstanding, since we are still igno- rant of the physiology which is controlled to be constant by the homeostatic process. regardless, the two process model explains internal desynchronization, circabidian (approxi- mately h) rhythm and the relation between the time of sleep deprivation and the length of following recovery sleep. however, the two process hypothesis is still not supported by biological experiments. one of the major reasons for the present situation is a lack of an adequate animal model for human sleep and wakefulness, which is characterized by internal desynchronization, circabidian rhythm, non-photic entrainment and consolidated sleep and wakefulness. these characteristics are unique to humans and, to my knowledge, have never been demonstrated in experimental animals such as rats and mice except for non-photic entrainment by feeding. methamphetamine, a central stimulant, is demonstrated to mimic human sleep and wakefulness in terms of the abovementioned four characteristics when chronically administered by dissolving in drinking water in rats and mice. the mechanism underlying methamphetamine- induced internal desynchronization seems to be an inde- pendent oscillator called methamphetamine-induced oscillator (mao) or methamphetamine sensitive circa- dian oscillator (masco). methamphetamine is a stimu- lant of the central dopaminergic neurons. recently, circadian rhythms in the clock gene per expression in the several dopaminergic structures of the rat brain were reported to be reorganized by methamphetamine and run parallel with desynchronized behavior rhythms (natsubori et al. ). the findings support a two-oscillator model, an alternative hypothesis for the human sleep-wake cycle, which was proposed many years ago. hypotheses are useful to understand a complex phe- nomenon with a simple principle and to make testable predictions. but a tragedy is “a beautiful hypothesis slain by an ugly little fact” (thomas henry huxley). bs_bs_banner sleep and biological rhythms ; : doi: . /sbr. © japanese society of sleep research this is the accepted manuscript made available via chorus. the article has been published as: baryogenesis from oscillations of charmed or beautiful baryons kyle aitken, david mckeen, thomas neder, and ann e. nelson phys. rev. d , — published october doi: . /physrevd. . http://dx.doi.org/ . /physrevd. . pitt-pacc- baryogenesis from oscillations of charmed or beautiful baryons kyle aitken, , ∗ david mckeen, , † thomas neder, , ‡ and ann e. nelson , § department of physics, university of washington, seattle, wa , usa pittsburgh particle physics, astrophysics, and cosmology center, department of physics and astronomy, university of pittsburgh, pa , usa ahep group, instituto de física corpuscular — c.s.i.c./universitat de valència, parc científic de paterna, c/ catedrático josé beltrán e- paterna (valencia), spain (dated: september , ) we propose a model for cp violating oscillations of neutral, heavy-flavored baryons into an- tibaryons at rates which are within a few orders of magnitude of their lifetimes. the flavor structure of the baryon violation suppresses neutron oscillations and baryon number violating nuclear decays to experimentally allowed rates. we also propose a scenario for producing such baryons in the early universe via the out-of-equilibrium decays of a neutral particle, after hadronization but before nucleosynthesis. we find parameters where cp violating baryon oscillations at a temperature of a few mev could result in the observed asymmetry between baryons and antibaryons. furthermore, part of the relevant parameter space for baryogenesis is potentially testable at belle ii via decays of heavy flavor baryons into an exotic neutral fermion. the model introduces four new particles: three light majorana fermions and a colored scalar. the lightest of these fermions is typically long lived on collider timescales and may be produced in decays of bottom and possibly charmed hadrons. pacs numbers: . .fs, . .-c, . .ly, . .nb i. introduction the puzzle of baryogenesis, how the universe came to be composed primarily of matter rather than equal amounts of matter and antimatter, has led to numerous theories about physics beyond the standard model (sm), beginning with the pioneering work of sakharov [ ]. three ingredients are present in one form or another in any baryogenesis theory: baryon number violation, c and cp violation, and departure from thermal equilibrium. because baryon number violation is required, initially baryogenesis was thought to involve new baryon number violating processes which are only important at very high energies, although it was later realized that anomalous electroweak processes could do the job at temperatures as low as the weak phase transition [ ]. most baryogenesis models require the universe to re- heat after inflation to a high temperature, typically well above the weak scale. however, many theories of physics beyond the sm are inconsistent with a high inflation scale or are inconsistent with a high postinflation reheat scale. axion dark matter, if the axion is present during infla- tion, requires a low inflation scale in order to avoid ex- cessive isocurvature perturbations [ ]. supersymmetry requires a low reheat scale in order to avoid overproduc- tion of the gravitino [ ]. the relaxion solution to the hierarchy problem requires a low inflation scale so that the hubble temperature during inflation does not sup- press instantons [ ]. in addition, avoiding the need for ∗ kaitken @gmail.com † dmckeen@pitt.edu ‡ neder@ific.uv.es § aenelson@uw.edu a high reheat temperature or production of heavy parti- cles during reheating means a low baryogenesis scale is consistent with a wider variety of inflationary models [ ]. lower reheat temperatures are possible provided the inflaton decays produce heavy particles which decay out of thermal equilibrium in a baryon and cp violating manner [ ]. in ref. [ ] baryogenesis occurs due to the baryon number violating decays of tev mass squarks in an r-parity violating supersymmetric model, in which the reheat temperature could be as low as an mev, pro- vided that the heavy squarks can be produced out of equilibrium at the end of inflation. such squark medi- ated baryon number violation is consistent with the ob- served lifetime of the proton, due to the conservation of lepton number, and, depending on the flavor structure of the baryon number violating operators, can be consistent with the stability of heavy nuclei as well. a similar model involving the decays of majorana fermions was consid- ered in ref. [ ]. in ref. [ ] it was pointed out that heavy flavor baryon number violation could lead to oscillations of the Ξ b baryon at a rate comparable to its lifetime, while being consistent with the lifetime of heavy nuclei. enhanced baryon number violation involving heavy fla- vors was also studied in ref. [ ]. here we present a baryogenesis model which is consis- tent with a reheat temperature as low as a few mev, and which requires no postinflationary production of any par- ticle heavier than about — gev. the required baryon number violation is conceivably observable via the oscil- lations of heavy-flavor neutral baryons, and the required cp violation is potentially of o( ) in such oscillations. the processes that produce the baryon asymmetry in the early universe involve particles and phenomena which can be directly studied in the laboratory – a unique fea- ture of our theory. our proposal is that certain neutral mailto:kaitken @gmail.com mailto:dmckeen@pitt.edu mailto:neder@ific.uv.es mailto:aenelson@uw.edu heavy flavor baryons undergo cp and baryon number violating oscillations and decays, and are produced in the early universe via the out of equilibrium decays of a weakly coupled neutral particle whose lifetime is of or- der . s, a time when the temperature is of order a few mev. the basic scenario was outlined in ref. [ ], and the model we study has the same field content and cou- plings as ref. [ ]. the basic formalism for analyzing cp violation in fermion antifermion oscillations was worked out in ref. [ ]. the outline of the paper is as follows. in section ii the model is introduced, and the effective operator responsi- ble for baryon oscillations is constructed. in section iii, general ∆b = , six-quark effective operators are ana- lyzed for their contribution to dinucleon decay, that is, the decay of two nucleons into mesons. currently, dinu- cleon decay places similar or stronger constraints on all such operators than does neutron oscillations. for oper- ators that cannot contribute to dinucleon decay at tree level, electroweak corrections to the six-quark operators are examined. in section iv, the general formalism for cp-violating oscillations of fermions is reviewed, and the oscillation parameters are calculated for the model in- troduced in section ii. in sections v and vi, direct con- straints on the masses and couplings of the new φ and χ particles from collider searches, and indirect constraints from rare decays of mesons and baryons are derived, re- spectively. section vii contains our analysis of how in this model the baryon asymmetry of the universe (bau) is produced. finally, in section viii we conclude and point at possible directions for future work. ii. model we wish to find a theory which allows for sufficiently large baryon number and cp violation to explain baryo- genesis at relatively low energy. in order to ensure suf- ficient stability of the proton, we assume lepton number is not violated, other than perhaps via the tiny ∆l = terms that could account for majorana neutrino masses. the lowest dimension terms which violate baryon num- ber and not lepton number are dimension , six-quark ∆b = operators. such operators can lead to neutral baryon oscillations and conceivably cp violation [ ], and can arise as an effective field theory description of physics at some higher energy scale. a minimal renor- malizable model for generating such terms involves a new charge − / color triplet scalar and two majorana fermions, as described in ref. [ ]. a third majorana fermion, which decays out of thermal equilibrium, allows for the fulfillment of the out-of-equilibrium sakharov con- dition. we note that this model for baryon number violation can easily be embedded in an r-parity violating super- symmetric (rpv susy) theory. in such theories, the neutralinos would play the role of the majorana fermions and a down-type su( ) singlet squark can be the colored scalar. for simplicity, we do not explore this embedding in a susy framework in this paper and we stick to the minimal version of the model. our model thus adds four new particles: three ma- jorana fermions, χ , , , and a single color triplet scalar, φ. the interactions involving the new particles and weak su( ) singlet sm quarks are given by lint ⊃−g∗udφ∗ūrdcr −yidφχ̄idcr + h.c., ( ) along with terms involving other generations, d → s,b and u → c,t. by convention we take all two component fields to transform in the left-handed representation un- der lorentz transformations. dcr stands for the charge conjugate of the right-handed down quark field, which is in the left-handed lorentz representation. in this ex- pression and throughout the paper, we work in the mass basis, which is unambiguous for su( ) singlet quarks. the required new particles and their interactions are motivated as follows. a natural way to construct the ∆b = six-quark operator we require for baryon oscilla- tions is from two ∆b = four-fermion interactions con- nected by an exotic neutral majorana fermion. thus we introduce an exotic, electrically-neutral, colorless, majo- rana fermion, χ , which couples to other fermions via a four-fermion interaction of the form urdrd′rχ (using u and d here to represent any up- or down-type quark). since such a four-fermion interaction is itself nonrenor- malizable, we also introduce a complex, color triplet, scalar particle (diquark) φ to mediate the ∆b = in- teractions. note that if χ is heavier than the difference in mass between the proton and electron, mp − me = . mev, this interaction does not give rise to proton decay. in the presence of only χ , there is no physical cp violation, as there is enough reparameterization free- dom to remove the phases in the couplings. we introduce a second fermion, χ (with mχ > mχ ), in order to give rise to cp violation. finally, for baryogenesis, the oscil- lating baryons must be produced out of thermal equilib- rium. as described in sec. vii, this is most simply ac- complished by introducing a third majorana fermion, χ , which decays out of equilibrium to produce the baryons whose oscillations result in baryogenesis. note that we only consider operators constructed out of right-handed quarks, for two reasons. our phenomeno- logical reason is that, as we will show in sec. iii, right handed quark operators are less constrained by dinucleon decay due to the requirement of light quark mass inser- tions in flavor-changing loops. our top down theoretical reason is that, as mentioned, the interactions in eq. ( ) occur in rpv susy models, suggesting a possible em- bedding of our model into a more complete theory. models of baryogenesis that generate four-fermion interactions of this form and identify χi with right-handed neutrinos can be found in ref. [ ]. the stability of be leads to a marginally stronger lower bound of mχ > . mev [ ]. ur dr dr ūr d̄r d̄r φφ χ mχ fig. . the basic six-quark ∆b = operator generated by φ and χ exchange. u and d here represent any of the up- or down-type quark flavors. the quarks involved are all weak su( ) singlets, as emphasized by the r subscripts. figure shows the ∆b = six-quark operators that are generated by the interactions in eq. ( ). such oper- ators, which can mediate the transition of a baryon b to an antibaryon b̄′, can be written as obb′ = �abc�def × [ (qr) i a (qr)i,b (qr) j c (q ′ r)j,d (q ′ r) k e (q ′ r)k,f + . . . ] , ( ) where a,. . . ,f are color indices, i,j,k spinor indices, and q = u,d,s,c,b any of the quark flavors (because of its short lifetime, the top quark does not hadronize and is not important in the low-energy effective theory) which are all right-chiral. the ellipsis represents other possible permutations of color or spinor indices. here, b denotes an arbitrary standard model baryon with the quark con- tent qqq while b′ contains q′q′q′. [we will use both the baryon name b or the quark content (qqq) to label the operators in question throughout this paper.] the pre- cise index structure of obb′ is not important for the pur- poses of this paper. therefore, in what follows, we will suppress the indices on obb′ and generically denote the operators we are interested in that appear in the effective lagrangian via the shorthand leff ⊃ cbb′ (qqq) (q′q′q′) ≡ cbb′obb′, ( ) keeping in mind that the leading operators that are gen- erated involve only right-chiral quarks. matching the interactions generated by eq. ( ) to the effective theory at tree-level gives the coefficient of the operator that generates oscillations between a neutral baryon and its antiparticle, b ↔b̄, cbb ∼ ∑ i mχi m b −mχ i ( g∗udyid′ + g ∗ ud′yid m φ ) , ( ) with u, d, and d′ labeling the quarks comprising b. for example, the operator (ddc) would allow the processes Σ̄c ↔ Σc. given this operator, we will find it useful to relate the coefficient to the (dispersive) transition ampli- tude, defined by δbb ≡〈b̄|cbbobb|b〉, with δbb = κ cbb, ( ) where κ ∼ − gev [ ]. in analogy with meson oscil- lations, when the two-state system in question is unam- biguous, δbb can also be referred to as m . operators which involve different baryons of the form obb′ would allow for a common decay product between b and b̄ and could also give rise to oscillations. for example, (uss) (uds) would allow for Ξ and Ξ̄ to have a common decay product, through Ξ → Λ and Ξ̄ → Λ (ignoring any neutral meson products). however, we will find such processes are suppressed relative to their direct oscillation cousins, so we will ignore them in our analysis. there are also baryon-number–preserving operators that contribute to the masses and mixings of sm baryons. these are greatly suppressed relative to those that occur in the sm and we do not consider them further either. therefore, in what follows, we focus on operators obb with coefficients of the form of eq. ( ). iii. dinucleon decay constraints as described in the preceding section, we would like our six-quark operators to allow for the oscillation of heavy baryons in order to produce the universe’s ob- served baryon asymmetry. in sec. vii, we will show that the ideal width for such an oscillation, which is depen- dent upon the value of cbb in eq. ( ), is a few orders of magnitude smaller than b’s decay width. however, mod- els with b violation by two units are certainly not a new idea, and so significant experimental effort has been put fourth into constraining ∆b = processes. the most immediate constraint on our six-quark operators is the lack of observed dinucleon decay, which we quantify in this section. the analysis we perform here applies to six-quark operators in general and is independent of the origin of the new physics introduced in sec. ii. dinucleon constraints come from underground detec- tors whose primary purpose is the detection of proton decay and neutrino oscillations. for example, in a nu- cleus, a n → n̄ transition will be shortly followed by the annihilation of the n̄ with one of the other nucleons, leading to the decay of the nucleus of mass number a to a nucleus with a′ = a − plus mesons. the lack of observation of such decays can therefore bound the transition amplitude δnn [ ] which is related to the co- efficient of the (udd) operator, cnn [cf. eqs. ( ) and ( )]. currently, the lower bound on the o lifetime (in decays to pions) of . × years from the super- kamiokande collaboration [ ] places the strongest limit, δnn < . × − gev. operators that also violate strangeness do not directly induce n → n̄ transitions in a nucleus. however, they can also lead to dinucleon decays, a → (a− ) + mesons, through the reaction nn → kaons + x where n is a nucleon. for example, the diagram on the left of fig. shows how the operator (uds) can lead to dinucleon de- cay to a pair of kaons. the super-kamiokande collabo- ration [ ] has searched for such decays and has placed s̄ s̄d u d u/d u/d u p/n p/n k+/k k+/k s̄ s̄ s̄ u d u d u/d u/d u s w ± p/n p/n k+/k k+/k k fig. . left: dinucleon decay via the ∆b = ∆s = (uds) operator that mediates Λ ↔ Λ̄ oscillations. right: din- ucleon decay mediated by the ∆b = , ∆s = (uss) operator that becomes ∆s = (uds)(uss) operator in the presence of flavor-changing weak interactions. because the short-distance ∆b = operators we consider involve weak isosinglets, this operator requires light quark chirality flips, indicated by crosses. see text for discussion of the match- ing of the short distance theory onto the (chiral symmetry violating) long distance theory. an upper bound on the pp → k+k+ decay rate by lim- iting the lifetime for o → c k+k+ to more than . × years. to make use of this limit, we start with the effective operator obb. the dinucleon decay rate through direct nucleon annihilation can then be roughly approximated by considering the decay rate to a meson pair [ ], Γnn→x ∼ π |cbb| m n |〈 mesons|obb|nn〉| ρn ( ) where mn is the nucleon mass, ρn ' . fm− is the nucleon density, and we have ignored the masses of the final state particles. in the case of operators that can con- tribute at tree level, the matrix element can be estimated as roughly 〈 mesons|obb|nn〉∼ Λ qcd ' ( mev) . using this and eq. ( ), the limit on the rate for nn → kk from super kamiokande translates to a limit on the transition amplitude of δ(uds) . − gev. ( ) in what follows, we also take operators that change strangeness by one or three units to have roughly the same bound as this. kinematic constraints protect certain operators from contributing to dinucleon decay at leading order. op- erators such as (uss) that change strangeness by four units (i.e. ∆s = ) are kinematically forbidden from con- tributing to dinucleon decay at tree level since mn < mk. similarly, those that involve charm or bottom quarks also do not lead to dinucleon decay at leading or- der. however, when combined with flavor-violating weak depending on the nucleon binding energy, nn → dγ through a ∆c = operator is kinematically allowed for some nuclei, interactions, these operators involving heavy quarks can lead to dinucleon decay. an illustration of this is shown on the right of fig. . to properly estimate the rate for dinucleon decay from ∆b = operators (involving heavy flavors), we must match the uv theory involving quarks to a low energy effective theory involving baryons valid at momentum transfers below πfπ ∼ gev where fπ = mev. this consists of writing down an operator in the uv theory and treating the coefficient of this operator as a spurion that transforms in a particular way under the global chiral quark flavor symmetry su( )l×su( )r so as to make the operator invariant. this operator is then matched onto an operator in the effective theory that transforms in the same way under the chiral symmetry with the same spurion coefficient. in the uv, the light quarks ql,r transform as triplets under su( )l,r. in the low energy theory, the meson octet, Π, is described by a field Σ = exp ( iΠ/fπ) which transforms under the chi- ral symmetry as Σ → lΣr† where l, r are su( )l,r transformations, respectively. incorporating the baryon octet (see, e.g., ref. [ ]) can be done by defining a field ξ = exp (iΠ/fπ) which transforms as ξ → lξu†, ξ → uξr† under su( )l,r. u is an su( ) matrix that depends nonlinearly on the meson fields. the baryon octet b is defined to transform as b → ubu†. oper- ators in the effective theory are then constructed out of Σ, b, and ξ along with spurions from the uv theory to be invariant under the flavor symmetry. since the chiral symmetry is dynamically broken by the strong coupling of qcd around πfπ, one can use naive dimensional anal- ysis to properly account for factors of π (that come from the strong coupling) and the cutoff, πfπ, that appear in this matching procedure, as described in, e.g., ref. [ ]. we will first illustrate this matching procedure in our theory with interactions given by eq. ( ), assuming for now that only the light quarks u, d, and s are involved. we will deal with heavy quarks c and b below. since distinction between chiralities is necessary, we will tem- porarily denote them explicitly. after integrating out the scalar, φ, and the majorana fermions, χi, we are left with a ∆b = operator involving only (light) right-chiral quarks, cbb(qrqrqr) . this operator must be matched onto an operator valid at long distances involving baryons at the scale of chiral symmetry breaking. the coeffi- cient cbb can be treated as a spurion that transforms under su( )r in a representation that appears in the tensor decomposition of triplets. for definiteness, take it to transform as an su( )r octet. then the object c̃bb ≡ ξcbbξ† transforms as c̃bb → uc̃bbu† and the but due to the dependence of the amplitude on the photon mo- mentum and coupling and phase space suppression the rate is proportional to (α/ π) (kγ/mn ) ∼ − , where kγ is the pho- ton energy, suppressing the rate below other decays with less constrained phase space. operator matching is cbb(qrqrqr) → ( πf π ) trbc̃bbb + . . . , ( ) where the ellipsis represents other possible orderings of the baryon octets and the spurion. note that this gives an understanding of the size of κ ∼ πf π ' − gev in eq. ( ). adjusting this analysis if cbb transforms under a different representation of su( )r is straightforward; one inserts the required numbers of ξ and ξ† into the definition of c̃bb so that it transforms in such a way as to leave trbc̃bbb invariant. for example, if cbb is a singlet then one simply takes c̃bb ≡ cbb. four-quark weak operators involving light quarks can be matched onto the low energy effective the- ory in much the same way. the coefficient of the operator ūlγµq j lq̄liγµul can be viewed as a spurion that transforms as an octet under su( )l and the strangeness changing (∆s = ) coefficient takes a value ∝ gfvusv ∗udh with hij = δi δ j . then ξ†hξ → uξ†hξu† and the matching is gf√ vusv ∗ udūγ µ ( −γ ) sd̄γµ ( −γ ) u → gf√ vusv ∗ ud ( πf π ) trb̄ξ†hξb + . . . , ( ) where again the ellipsis represents other possible order- ings of b, b̄, and ξ†hξ. now we can combine a ∆b = operator that also changes strangeness by n units with the weak ∆s = operator to form a ∆b = , ∆s = n− operator that is given by gf√ vusv ∗ udf π ( πf π ) trb̄c̃bbξ †hξb + . . . . ( ) in other words, if the leading ∆b = operator has ∆s = n, the ∆b = , ∆s = n − operator that is generated due to weak interactions is suppressed relative to it by the factor gf√ vusv ∗ udf π ∼ − . ( ) thus, for example, the bound on a leading ∆s = op- erator (ursrsr) from the lack of dinucleon decay is around eight orders of magnitude weaker than that on the ∆s = operator (uds)(uss) [which we take to be comparable to that on the ∆s = operator (uds) ], δ(uss) . − gev. ( ) now, we consider the case where the leading ∆b = operators contain heavy quarks. consider, for example, if after integrating out the heavy scalar φ and majo- rana fermions χi, that the leading operator we generate is c(udb) (urdrbr) . before matching onto the theory valid after chiral symmetry breaking we must first inte- grate out the b quarks. in the presence of weak interac- tions, as shown in fig. , doing so will lead to a ten-quark ⟨ūlur⟩ ⟨ūlur⟩dl dl ul drdr ul b b fig. . the ten-quark ∆b = operator that results from the leading (urdrbr) operator after integrating out the b quarks. the crosses represent chirality-flipping b quark mass insertions. we use 〈ūlur〉 to indicate the pairs of light quark fields that can be replaced by the chiral condensate when matching onto the long distance theory relevant for dinucleon decay. operator, c(udb) (urdrbr) → ( gf√ vubv ∗ ud mb ) ×c(udb) (urdrdlūlul) . ( ) after chiral symmetry breaking, ūlur can be replaced by the quark condensate which is roughly πf π. this means that the induced ∆b = operator (uldrdl) is suppressed relative to (urdrbr) by the factor( gf√ vubv ∗ ud πf π mb ) ∼ − . ( ) additionally in the case of a leading operator containing a b and c quark, e.g. (drcrbr) , there are perturbative loops that generate dimension-nine operators involving light quarks above the chiral symmetry breaking scale. in the case of the operator (drcrbr) , two such loops can be used to generate the operator (uldldr) with a coefficient suppressed relative to the leading one by( gf√ vubv ∗ cd mbmc π log m w m b ) ∼ − . ( ) in table i, we list operators that can mediate b ↔ b̄ transitions along with the number of loops required for each operator to mediate (∆s = , , , ) dinucleon decay. we show the resulting limits on the transition amplitudes δbb = |m | = κ cbb of each operator from the lack of observation of dinucleon decay, accounting for the appropriate suppression factors. in general we find that only operators which require or more weak interactions to contribute to dinucleon decay can give baryon oscillations at a rate which is large enough to be relevant for either experimental searches or baryogenesis. the last column of the table gives the limit on the size of the operator that can be produced in our specific model when collider constraints on new particles are considered, which will be discussed in sec. v. iv. cp violation in heavy baryon oscillations the evolution of the (b, b̄) system in vacuum, assum- ing cpt conservation, can be described [ ] by a × hamiltonian, h = m − i Γ = ( mb − i Γb m − i Γ m∗ − i Γ ∗ mb − i Γb ) . ( ) m and Γ are both hermitian matrices that describe the dispersive and absorptive parts of the b, b̄ → b, b̄ am- plitude, respectively. this system is entirely analogous to the very well known case of neutral mesons and an- timesons. because of the off-diagonal terms in h, the mass eigenstates |bl,h〉 with masses ml,h are linear com- binations of the flavor eigenstates |b〉 and |b̄〉, |bl,h〉 = p|b〉±q|b̄〉. ( ) the mass difference is ∆m = mh−ml > and the width difference between the states is ∆Γ = Γh−Γl and can be of either sign. the flavor admixtures can be determined by ( q p ) = m∗ − (i/ )Γ∗ m − (i/ )Γ . ( ) a state that begins at t = as a |b〉 or |b̄〉 is at time t |b(t)〉 = g+(t)|b〉− q p g−(t)|b̄〉, |b̄(t)〉 = g+(t)|b̄〉− p q g−(t)|b〉 ( ) with g±(t) = ( e−imht− Γht ±e−imlt− Γlt ) . ( ) a particularly useful quantity that measures the level of cp and baryon number violation is the quantity, ab = pb→b −pb→b̄ + pb̄→b −pb̄→b̄ pb→b + pb→b̄ + pb̄→b + pb̄→b̄ , ( ) where, e.g., pb→b̄ is the time integrated probability for an intitial b state to oscillate into a b̄ and the other terms are defined analogously. in terms of the elements of h, this can be concisely expressed, ab = im (m∗ Γ ) Γ b + |m | . ( ) this expresses the familiar fact that cp violation requires a phase difference between the absorptive and dispersive parts of the transition amplitudes. the dispersive part of the transition amplitude, m , is dominantly given by off-shell χi exchange in our model, as seen in fig. . we have already written down what we need to estimate this in eqs. ( ) and ( ), resulting in m ∼ κ ∑ i mχi m b −mχ i ( g∗udyid′ m φ ) . ( ) here, u, d, and d′ refer to the flavors that comprise b and we have assumed, if d = d′, that g∗udyid′ � g∗ud′yid. if we concentrate on the contribution due to a particular χi and express it in terms of its mass difference from the baryon, ∆mbi = mb −mχi, we have |m |i ∼ κ ∆mbi ∣∣∣∣∣g ∗ udyid′ + g ∗ ud′yid m φ ∣∣∣∣∣ ' × − gev ( mev ∆mbi ) × ( gev mφ/ √ |g∗udyid′ + g∗ud′yid| ) . ( ) the absorptive part of the transition amplitude re- quires an on-shell state into which both b and b̄ can decay. this requires at least χ to be light enough for either baryon or antibaryon to decay into it. cp viola- tion will be largest when the mass splitting between χ and b is not too large. in this case the most important states for Γ are decays of b to χ plus a meson. the contribution from χ π , for instance, can be estimated using the effective lagrangian, leff ⊃−yibπ b̄iγ χi + h.c., ( ) where yib ∼ πκ mb g∗udyid′ m φ . ( ) the factor of π in this expression accounts for the non- perturbative nature of the interaction, which is similar to the pion-nucleon vertex. this interaction gives a con- tribution to Γ of Γ ∼ ∑ i y ibmχi π ( + rχi −rπ ) λ / ( ,rχi,rπ ) , ( ) where rχi,π = m χi,π /m b and λ (a,b,c) = a + b + c − ab − ac − bc. the magnitude of the contribution to Γ from a particular χi is roughly |Γ |i ∼ y ib π ∆mbi ∼ πκ m b ∣∣∣∣∣g ∗ udyid′ m φ ∣∣∣∣∣ ∆mbi ' × − gev ( ∆mbi mev ) × ( gev mb ) ( gev mφ/ √ |g∗udyid′| ) . ( ) operator b weak insertions measured limits on δbb = m (gev) required Γ (gev) [ ] dinucleon decay collider (udd) n none ( . ± . ) × − − − (uds) Λ none ( . ± . ) × − − − (uds) Σ none ( . ± . ) × − − − (uss) Ξ one ( . ± . ) × − − − (ddc) Σ c two ( . + . − . ) × − − − (dsc) Ξ c two ( . + . − . ) × − − − (ssc) Ω c two ( . ± . ) × − − − (udb) Λ b two ( . ± . ) × − − − (udb) Σ b ∗ two ∼ − ∗ − − (usb) Ξ b two ( . ± . ) × − − − (dcb) Ξ cb † two ∼ − † − − (scb) Ω cb † two ∼ − † − − (ubb) Ξ bb ‡ four ∼ − ‡ > − (cbb) Ω cbb † four ∼ − † > − table i. operators that mediate b ↔b̄ oscillations and the number of weak interaction insertions required for each of these to contribute to dinucleon decay. the resulting limit from dinucleon decay on the transition amplitude, defined in eq. ( ), for each operator is shown. an ∗ indicates a baryon that has not yet been observed and which has a strong decay channel open. a † (‡) indicates an unobserved baryon which primarily decays through a weak interaction of a c (b) quark. we now see the reason we need at least two majorana fermions. if there were only a single majorana fermion, χ , that contributed to m and Γ , they would have the same phase and ab in eq. ( ) would vanish. thus, we use contributions from χ and χ exchange to obtain a physical, cp-violating phase difference between m and Γ . the ratio of the single meson contribution to Γ from χ to its contribution to m is∣∣∣∣ Γ m ∣∣∣∣ ∼ π ( ∆mb mb ) ' . ( ∆mb mev ) ( gev mb ) . ( ) the cp-violating quantity ab in eq. ( ) linearly de- pends on |Γ |. without finely tuning the contributions due to χ and χ against each other, this value of the ratio due to χ alone is roughly as large as the total ratio |Γ /m | can get. v. collider constraints to obtain a large amount of cp violation in heavy baryon oscillation, it will be clear that the lightest two majorana fermions must have masses on the order of a few gev along with couplings to quarks that are not too small. in this discussion, we consider the two lightest ma- jorana fermions. the third, χ must be weakly coupled in the minimal version of the model, due to cosmological considerations as we will see in sec. vii. the constraints that we will discuss in this section re- quire that φ have a mass of at least a few hundred gev. in this case, χi decays can be analyzed by integrating out the scalar in eq. ( ) resulting in four-fermion inter- actions, − gudyid ′ m φ χ̄iūrd c rd ′c r + h.c. ( ) (for d = d′, we have again assumed that gudyid′ � gud′yid.) both the interactions responsible for the de- cay of the majorana fermions and those that source cp-violating baryon oscillations are of the same form. the quarks involved in the decay operator must be lighter than those responsible for baryon oscillations and the couplings responsible for decay must be relatively smaller, to avoid stronger dinucleon decay limits from ∆b = quarks involving light quarks. the interaction in eq. ( ) allows for the decay χi → udd′, where u, d, and d′ are up- and down-type quarks light enough for this to be kinematically allowed. it is reasonable to assume that one mode dominates their al- lowed branchings and in this case, their lifetimes are τχi ∼ ( π) m χ , ∣∣∣∣∣ m φ gud yid′ ∣∣∣∣∣ ' − s ( gev mχi ) ( mφ/ √ gud yid′ tev ) . ( ) for mχi = gev, with couplings gud yid′ . (mφ/ tev) the ∆b = transition amplitude in the udd′ system is less than − gev, avoiding con- flict with constraints from dinucleon decay (see table i). furthermore, if mχi = gev, as long as gud yid′ & (mφ/ tev) , τχi . . s which is a short enough lifetime to avoid spoiling successful bbn (see, e.g., [ ]). we might ask whether instead of ensuring that χ , decay fast enough to avoid spoiling bbn, the lightest fermion χ could instead be long enough lived to serve as dark matter. first we note that the range allowed for kinematic stability of both proton and χ is extremely fine tuned, with the χ mass between mp − me and mp + me. if we assume all the χ’s participate in a vi- able heavy flavor baryogenesis mechanism, we will see that we must require the χ , masses to be around – gev, and we also need sufficiently large four-fermion interactions involving χ , and heavy flavor quarks, sup- pressed by a scale Λheavy ≡ mφ/ √ gy ∼ gev. here g and y here label couplings with the relevant flavor struc- ture. based on our discussion in sec. iii, at the one loop level we must generate four-fermion operators involving light quarks (into which χ , can decay) are generated with a scale Λlight & Λheavy ∼ gev. this pro- vides a lower bound on the strength of the light quark four-fermion operator which gives an upper bound on the χ , lifetime of τχ , . s in the absence of fine- tuning against some other source of this operator. there is also an unavoidable decay channel that comes from the mixing of χ , with the heavy flavor baryon, b, whose oscillations are responsible for the bau, with a mixing angle θ ∼ |m |/∆m where ∆m is the mass splitting be- tween the majorana fermions and b. this mixing leads to the decay of χ , into b’s decay channels with a partial width proportional to θ Γb, which is much shorter than the lifetime of the universe. we see that the majorana fermions are generically un- stable but long-lived on the scale of collider experiments and appear as missing energy. decay lengths on the or- der of to m are expected, potentially relevant for the recently proposed mathusla detector [ ] which is optimized to search for long-lived particles. in what follows, to analyze collider constraints on the new scalar φ we will assume that any χi produced at a collider is invisible and defer discussion of the displaced decay sig- natures at, e.g., mathusla. now that we know that the χi’s are invisible at col- liders, we can understand how the scalars appear when produced in hadron collisions. because φ is a color fun- damental, if it is kinematically accessible, φφ∗ pairs are easily produced in proton-(anti)proton collisions, and the signatures are essentially those of squarks in rpv susy. in addition to qcd production, (single) scalars can be resonantly produced in the presence of some nonzero gud. once produced, the scalar decays through one of the in- teractions in eq. ( ), either to quark pairs with a rate Γφ→ūd̄ ' ∑ i,j ∣∣guidj∣∣ π mφ, ( ) or to χi plus a quark, Γφ→χd ' ∑ i,j ∣∣yidj∣∣ π mφ, ( ) where we have assumed that mφ is much larger than the mass of any decay product. therefore, these scalars can appear in searches for dijet resonances (either singly or pair produced) and (mono)jets and missing energy. which search is most sensitive depends on mφ and the branching fractions for φ → ūd̄ and φ → χd. taken together, lhc searches for pair produced dijet resonances, both with [ ] and without [ ] heavy flavor in the final states, as well as standard susy searches for (b-tagged [ , ] or not [ , ]) jets plus missing en- ergy rule out φ masses below about gev. above this mass, limits from pair produced dijet resonances are no longer constraining while resonant production of a sin- gle φ with a rate proportional to |gud| for some u, d is important [ ]. we use the limits from resonant di- jet production from [ ] and recast searches for jets and missing energy [ – ] as well as monojets [ ] to find limits on the couplings gud and yid′ as functions of mφ. we find this limit for every flavor u, d, and d′, assuming that only gud and yid′ are relevant. given these limits, the maximum value of the product of couplings gudyid′ at each mφ can be found, and taking a value of the mass splitting between χi and the udd′ baryon, which can be turned into an upper limit on the transition amplitude δudd′ = m in the udd′ system. we show the upper limit on m as a function of mφ for each pattern of flavors u, d, and d′, assuming the dominance of one par- ticular pair of couplings gud, yid′ and a mass splitting between mχi and the udd ′ baryon of mev in fig. . we also show the largest value of m allowed from col- lider searches in each neutral baryon system in table i. lastly, we note that the six-quark ∆b = operators themselves can lead to interesting signatures at the lhc. these were studied in ref. [ ]. vi. hadron phenomenology a. hadron decays after integrating out the heavy colored scalars, four- fermion interactions between the majorana fermions and quarks are generated as in eq. ( ). these can lead to new decays of hadrons to final states that differ in baryon note that we perform this scan for a single majorana fermion. including a second, as we must to obtain cp violation, does not change the allowed values by more than an o( ) factor which, given our level of precision, is unimportant. the third, χ must be more weakly coupled than χ , and can be even more safely neglected here. �� -�� -�� -�� -�� ϕ (��) |� � � | (� �� ) �� -�� -�� -�� -�� |� � � | (� �� ) �� fig. . upper limits on m as functions of mφ that re- sult from collider searches for diject resonances and jets plus missing energy, assuming the dominance of the product of couplings gudyid′ indicated, where u and d (′) label generic up- and down-type quarks, respectively. we have taken ∆mb = mb −mχ = mev. top: the limits when yid or yis are dominant. bottom: the limits when yib is dominant. solid curves show the limits in the case where the charge / quark involved is u while dashed lines show the limit in the case of the c quark. number by one unit along with any kinematically acces- sible χi, e.g., meson → baryon + χi [+ meson(s)], baryon → meson(s) + χi. ( ) as we showed in sec. v, on the scale of particle physics experiments, χi appear as missing energy. for definiteness, let us focus now on four-fermion in- teractions that involve the b quark and the lightest ma- jorana fermion. this is potentially relevant to the case where baryons containing b quarks undergo cp-violating oscillations in the early universe, producing the bau; operators involving heavy quarks are less constrained by dinucleon decay and are therefore more promising candi- dates, cf. table i. similar considerations apply for oper- ators involving lighter quarks. consider, as a definite example, b decays through the operator − guby d m φ χ urdrbr, ( ) where u and d here are the actual up and down quarks. (we have omitted the contribution to this operator from gudy b which is more constrained by collider searches.) the rate for the b quark to decay through such an inter- action is Γb→χ ūd̄ ∼ mb∆m ( π) ( guby d m φ ) + o ( ∆m m b ) ' × − gev ( ∆m gev ) ( . tev mφ/ √ guby d ) . ( ) in this expression ∆m is the mass splitting between χ and the bottom quark (we have ignored masses in the final state besides mχ ). we have chosen to nor- malize this expression on values of the mass splitting and mφ/ √ guby d that result in a transition amplitude of |m | ∼ − gev in the Λ b = (udb) baryon system, which is the rough collider limit. given this mass split- ting, this can lead to decays of b+ mesons to a nucleon and χ with a branching ratio of brb±→nχ +x ∼ × − ( ∆m gev ) × ( . tev mφ/ √ guby d ) , ( ) where x represents possible additional pions. this is not a small branching fraction, although final states of this form have not yet been searched for in b meson decays. however, the requirement that the final state hadrons carry baryon number means that this decay is kinemati- cally forbidden if mχ > mb± −mp = . gev. decays of bottom baryons would be allowed to proceed for split- tings down to mπ, and one could expect branching ratios on the order of − for the parameters in eq. ( ). we also expect “wrong sign” decays of heavy baryons in this model, following a b →b̄ oscillation, with a branch- ing fraction that is roughly |m | Γ b . ( ) consider, e.g., the Ω c. given the constraints that appear in table i, this branching could potentially be as large as − . the belle ii experiment hopes to collect ∼ ab− of e+e− data at √ s = . gev collecting about × b meson pairs. if Ω c baryons are produced in % of b the calculation of the baryon decay rate to χ and a single meson is essentially the same as that of Γ in sec. iv, modulo a factor of mb/mχ ∼o ( ). meson decays (comparable to the measured production of Λc baryons), then there would be a sample of about Ω c’s and Ω̄ c’s. thus, there could be a few hundred “wrong sign” decays in the data sample. while this would be a challenging measurement, it is interesting that it is in principle observable at the next generation b-factory given current experimental limits. we mention here that baryon-number–violating decays of baryons along these lines have been searched for by the clas collaboration [ ]. the branching fraction for Λ → k s + inv. is limited to less than × − while that for Λ → p̄π+ must be less than × − which are sensitive to the operator (uds) . while interesting, these limit δ(uds) = |m | to less than about − gev, which is less strong than the limit on this operator from null searches for dinucleon decay. in light of the less stringent limits from dinucleon decay on operators involving heavy flavor, it would be highly desirable for searches for ∆b = decays of baryons with heavy quarks to be performed. b. meson oscillations in addition to the decays described above, the new interactions could lead to flavor-changing oscillations of neutral mesons. the limits from these processes on this model were considered in ref. [ ]; we refer the reader to [ ] and references therein for further details. avoiding these constraints requires a suppression of particular combinations of flavor-violating couplings. for example, considering kaon oscillations, given mφ & gev, ys and ys could be o( ) provided yd ,yd . − . similar considerations apply for flavor-violating combinations of the couplings gus and gud. the con- straints on charm and bottom couplings from d and b oscillations are less severe. from the model building point of view, flavor-changing meson oscillations can be naturally avoided, e.g. charging the scalar under a symmetry so that f −f is conserved, where f , label flavor quantum numbers. vii. cosmological production of the baryon asymmetry we now answer in detail the question of how the baryon asymmetry of the universe is produced in this model. in addition to the cp and baryon number violation de- scribed above, a nonzero asymmetry requires a departure from thermal equilibrium. the simplest possibility for this is to assume that χ is very weakly coupled. it is therefore long-lived and decays out of equilibrium, pro- ducing the baryons that undergo cp- and b-violating oscillations. at temperatures below mχ , the equations that deter- mine the radiation and χ energy densities are dρrad dt + hρrad = Γχ ρχ , ( ) dρχ dt + hρχ = −Γχ ρχ . ( ) h is the hubble parameter which is related to the total energy density, h = √ π ρ m pl ' √ π ρrad + ρχ m pl , ( ) where mpl = . × gev is the planck mass. in the absence of χ decays, ρrad and ρχ simply redshift like radiation and matter energy densities, respectively. the right-hand sides of these equations describe how χ decays cause the energy density in matter to decrease while dumping energy into the plasma. in addition to depositing energy in the plasma, some of the χ decays produce baryons and antibaryons, b and b̄, that can oscillate and decay, violating cp and b. for this to occur, the temperature of the universe needs to be below the qcd confinement temperature, tqcd ' mev. on the timescale of the expansion of the universe, h− , the (anti-)baryons produced this way rapidly oscillate and decay, producing a net b asym- metry. however, because of the presence of the plasma, with which they can interact, as well as their large anni- hilation cross section, b ↔ b̄ can decohere in this envi- ronment, suppressing the asymmetry that is generated. properly accounting for this requires a density matrix treatment, which has been used in a cosmological con- text for neutrino oscillations and oscillating asymmetric dark matter [ , ]. following ref. [ ] (see [ ] for a similar analysis in the context of baryogenesis-related os- cillations), we can write the boltzmann equations that govern the evolution of the number density of the b-b̄ system, dn dt + hn = −i ( hn−nh† ) − Γ± [o±, [o±,n]] −〈σv〉± ( {n,o±n̄o±}−n eq ) + Γχ ρχ mχ brχ →bo+, ( ) where the last term describes b and b̄ production through χ decay. brχ →b is the branching ratio for χ to decay to b or b̄. in this equation n and n̄ are density matrices, n = ( nbb nbb̄ nb̄b nb̄b̄ ) , n̄ = ( nb̄b̄ nbb̄ nb̄b nbb ) , ( ) and neq is the equilibrium density of baryons plus an- tibaryons. h is the hamiltonian seen in eq. ( ). 〈σv〉± and Γ± are thermally-averaged annihilation cross sec- tions and scattering rates on the plasma, respectively. o± is a matrix o± = ( ± ) . ( ) the subscript of 〈σv〉± and Γ±, i.e. whether they appear with o+ or o− in eq. ( ), is determined by the be- havior of the effective lagrangian that gives rise to these interactions under charge conjugation of only the heavy baryons, b ↔ b̄, leff ↔ ±leff. interactions that do not change sign are said to be flavor-blind while those that do are flavor-sensitive. for example, b and b̄ can scat- ter on light charged particles in the plasma through their magnetic moment, µ, which corresponds to a term in the effective lagrangian of iµ b̄ [γν,γρ]bfνρ. ( ) under b ↔ b̄ this term changes sign, so the rate for scattering via the magnetic moment appears with o− in the botzmann equation. it is useful to work in terms of the quantities Σ ≡ nbb + nb̄b̄, ∆ ≡ nbb −nb̄b̄, Ξ ≡ nbb̄ −nb̄b, Π ≡ nbb̄ + nb̄b. ( ) in this basis the boltzmann equations are( d dt + h ) Σ = Γχ ρχ mχ brχ →b − ΓbΣ − (re Γ ) Π + i (im Γ ) Ξ − [( 〈σv〉+ + 〈σv〉− )( Σ − ∆ − n eq ) + ( 〈σv〉+ −〈σv〉− )( Π − Ξ )] ,( d dt + h ) ∆ = −Γb∆ + i (re m ) Ξ + (im m ) Π,( d dt + h ) Ξ = − ( Γb + Γ− + 〈σv〉+Σ ) Ξ + i (re m ) ∆ − i (im Γ ) Σ,( d dt + h ) Π = − ( Γb + Γ− + 〈σv〉+Σ ) Π − (im m ) ∆ − (re Γ ) Σ. ( ) coherent oscillations from a flavor-symmetric state to an asymmetric state proceed through Σ → Ξ, Π → ∆. flavor-sensitive scattering and flavor-blind annihilation suppress Ξ and Π and therefore lead to decoherence. when they decay, b and b̄ create states that carry baryon number. the flavor-asymmetric configuration contributes to the difference between the baryon and an- tibaryon number densities,( d dt + h ) (nb −nb̄) = Γb∆. ( ) the dominant interaction of b and b̄ with the plasma is scattering on charged particles (mostly electrons at t . mev) via the magnetic moment term in eq. ( ). the cross section for this at temperatures well below mb is dσsc dΩ = α µ ( + sin θ/ sin θ/ ) ( ) which diverges at small scattering angle, θ → . this divergence is cut off at finite temperature by the inverse photon screening length, mγ. using this, the total cross section can be estimated as σsc ∼ πα µ log ( e m γ ) ( ) where e is the electron energy. taking e ∼ t , mγ ∼ et/ [ ] and µ ∼ /( mb), this gives σsc ∼ πα m b log ( πα ) . ( ) the (flavor-sensitive) scattering rate is therefore Γ− = Γsc ∼ σsc (ne− + ne+ ) ∼ πα m b log ( πα ) × ζ( ) π t ∼ − gev ( gev mb ) ( t mev ) . ( ) at temperatures above a few mev, as is needed for bbn, this rate is larger than a typical heavy baryon width and therefore strongly affects the b-b̄ oscillations. when solving the boltzmann equations, we take an annihilation cross section that is similar to that for pp̄ annihilation at low energies, 〈σv〉+ + 〈σv〉− = mb. ( ) we will find that only the total annihilation cross section and not whether it is flavor-blind or -sensitive is impor- tant, since Σ � ∆, Ξ, Π. furthermore the annihilation rate is always much smaller than the scattering rate at temperatures we are interested in, so its effect on the final asymmetry is subdominant and can generally be ignored. a. sudden decay approximation having removed the heavy baryons from the problem due to the short timescales in their system, the evolution equations are eqs. ( ), ( ), and ( ). these involve only the radiation energy density, χ density, and the baryon asymmetry. they can be simply studied using a sudden decay approximation to gain a rough estimate of the baryon asymmetry. we outline this estimate below. at some high temperature above mχ , we assume that χ was in thermal equilibrium with the plasma, fixing its number density for t . mχ to roughly nχ ' ζ( ) π t . ( ) as the universe cools the energy density in χ and radi- ation are equal. this occurs at the temperature teq = ζ( ) π g∗(t ) mχ . ( ) g∗ is the effective number of relativistic degrees of free- dom and here it is evaluated at t & mχ . this corre- sponds to the time teq = √ π g∗(teq) mpl t eq = √ πg∗(teq) π g∗(t ) ζ( ) mpl m χ . ( ) after this the universe is matter dominated and the en- ergy density in radiation and χ redshift as ρrad = ρeq ( teq t ) / , ρχ = ρeq ( teq t ) . ( ) we then assume that all of the χ ’s decay at the time tdec = /Γχ . the ratio of the energy densities just before decay is ξ ≡ ρχ (t − dec) ρrad(t − dec) = (teqΓχ ) − / = [ g∗(teq) g∗(t ) ] / [ g∗(t ) ] × ( mχ gev ) / ( − gev Γχ ) / . ( ) we use t−dec here to indicate the time infinitesimally be- fore decay. the dominance of the scattering rate over other scales in the problem allows us to make some simplifications of the evolution equations that are useful here. in this limit we can ignore the hubble rate as well as annihi- lation and the equations governing b and b̄ in ( ) can be integrated. this results in the evolution equation for the difference between baryon and antibaryon densities, eq. ( ), becoming( d dt + h ) (nb −nb̄) = Γχ ρχ mχ × im (m ∗ Γ ) brχ →b Γb (Γb + Γ−) + |m | ' Γχ ρχ mχ Γb Γ− �, ( ) which is valid for the cases we consider with |m | � Γb � Γ−. we have defined � ≡ im (m ∗ Γ ) Γ b brχ →b ' abbrχ →b, ( ) with ab from eq. ( ). using �, we can then relate the baryon asymmetry to the χ number density at decay, ηb = nb −nb̄ s(t+dec) = nχ (t − dec) s(t−dec) [ t(t−dec) t(t+dec) ] Γb Γ− � = t(t−dec) mχ ξ [ t(t−dec) t(t+dec) ] Γb Γ− �. ( ) here, t+dec is the time just after decay. the ratio of the temperatures just before and after decay is determined by ρrad(t + dec) = ( + ξ)ρrad(t − dec) so that t(t−dec) t(t+dec) = ( + ξ)− / ' ξ− / , ( ) and ηb ' ξ / t(t−dec) mχ Γb Γ− �. ( ) the temperature just before decay can be arrived at by evolving the radiation energy density, resulting in ηb ' √ π [ πg∗(tdec) ] / √ mplΓχ mχ Γb Γ− �. ( ) using the expression for the scattering rate in eq. ( ) evaluated at t(t+dec), ηb ' π ζ( ) √ πg∗(tdec) Γb� σscmχ Γχ mpl ≈ × − [ g∗(tdec) ] / ( mb gev ) ( Γb − gev ) × ( gev mχ )( − gev Γχ )( � − ) . ( ) therefore we see that a baryon asymmetry of the required size is possible for a heavy baryon system with � ∼ − , which requires |m |/Γb ∼ − with |m |/ |Γ | not small. b. full solution of the boltzmann equations to get a more precise estimate of the baryon asymme- try, we numerically solve the system in eqs. ( ), ( ), and ( ). as mentioned above, we need |m |/Γb to not be much smaller than around − . looking at ta- ble i, one potential candidate is the Ω cb where the dom- inant coupling involves the operator (dcb) . in fig. �� -�� -�� -�� -�� -� ��-� ��-� ��-� ��-� �� (��) � (�) η�η� �� (�ℬ+�ℬ _ )/� ��-� (�χ�/�) fig. . ηb = (nb −nb̄)/s (solid, black) as a function of the temperature or time from a numerical solution of eqs. ( ), ( ), and ( ) for parameters relevant to the Ω cb-Ω̄ cb system: mb = gev, Γb = × − gev, |m | = × − gev, |Γ /m | = . , arg(m∗ Γ ) = π/ , mχ = . gev, Γχ = × − gev, and brχ →b = . . we have taken the rate for heavy baryon scattering on the plasma from eq. ( ) and the annihilation cross section to be mb. this can be compared against the value of ηb (solid, gray) from a solution of eqs. ( ), ( ), and ( ) as well as using the sudden decay approximation (dashed, gray) in eq. ( ). also shown are the ratio of the number density of χ to the entropy density (multiplied by − , solid, orange) and the ratio of the b plus b̄ number densities to the entropy density (solid, purple). the dashed purple line shows the equilibrium b and b̄ density (in units of the entropy density). the measured value of ηb = . × − is given by the solid red line. we show the value of ηb as a function of temperature in the case of the asymmetry being sourced by the Ω cb-Ω̄ cb system, taking mb = gev, Γb = × − gev [ ], |m | = × − gev, |Γ /m | = . , arg(m∗ Γ ) = π/ , mχ = . gev, Γχ = × − gev, and brχ →b = . . we have used an annihilation cross sec- tion of mb (the results do not depend on whether it is flavor-blind or -sensitive) and the scattering rate given in eq. ( ). in addition, the temperature dependence of the scat- tering and annihilation rates is compared to the expan- sion rate of the universe as well as to the rates governing the baryon-antibaryon system in fig. . as mentioned before, the (decohering) scattering is the dominant pro- cess above temperatures of about mev and, in partic- ular, is always much larger than the annihilation rate. at high temperatures, the heavy baryon density tracks its equilibrium value and it begins to deviate from its equilibrium value when χ ’s begin to decay. although not directly evident from the plots (except through the change in the temperature vs. time), the out-of- equilibrium χ particles actually come to dominate the energy density of the universe prior to their decay. af- ter the χ decays, which we assume happens in less than �� -�� -�� -�� -�� -� ��-� ��-� ��-� �� (��) � �� (�) Γ�� 〈σ�〉(� ℬ+� ℬ _ ) � Γℬ �� Γ�� fig. . the temperature dependence of the rates involved in the numerical solution of eqs. ( ), ( ), and ( ). the parameters are the same as in fig. . in orange, from top to bottom are the scattering, annihilation, and hubble rates. the purple lines indicate the rates relevant to the b-b̄ system itself, Γb, |m |, and |Γ |, from top to bottom, respectively. ∼ . s, the universe undergoes a transition from being matter-dominated to radiation-dominated, reheating to a temperature above a few mev. we have numerically confirmed the rough accuracy of the sudden decay approximation prediction for ηb over much of the parameter space. maximal cp violation, and thus more baryon asymmetry per oscillation, oc- curs for arg (m∗ Γ ) = π/ and larger values of |m | and |Γ |. a larger branching ratio, brχ →b, would pro- duce more oscillating baryons per majorana decay. the value of ηb that is generated is maximized if χ decays when the universe’s temperature is about mev, i.e. τχ = /Γχ ∼ − s. if it decays earlier than this, heavy baryon scattering on the plasma leads to decoher- ence, suppressing the asymmetry. if if decays later, the universe does not have a sufficient baryon asymmetry at the time the neutrinos begin to decouple, when the universe is around mev. given the constraints on the transition amplitudes in table i, the most promising baryon that could allow for a large enough transition amplitude to source the bau is the as yet unobserved Ω cb. a relatively large value for |m | is needed in this case, not far from the collider limit, unless brχ →Ω cb were rather large. it should be noted that the collider limits discussed in sec. v which appear in table i depend on the specific model that we considered. it is conceivable that the model could be ex- tended in a way that makes the standard collider searches that we considered less constraining. for example, one could imagine making the φ decay to a large number of relatively soft jets by coupling to a heavy vector-like quark and a singlet which decay to a large number of col- ored objects. relaxing these limits could allow for other heavy flavor baryons to source the bau, potentially even observed baryons like the Ω c, Λ b, and Ξ b. on the other hand, since they involve low-energy effective operators, the dinucleon decay constraints are less model depen- dent. weakening them would require significant tuning of tree-level operators against those induced by weak in- teractions. viii. summary and outlook we have presented a model for producing the observed baryon asymmetry of the universe which avoids high re- heat temperatures. the asymmetry is generated through cp and b-violating oscillations of baryons occurring late in the hadronization era. our model minimally intro- duces three neutral majorana fermions and a single col- ored scalar, and could potentially be embedded into rpv susy. the Ωcb ∼ (scb) baryon emerges as our most promising candidate when constraints due to collider data and din- ucleon decay are taken into account. note that the con- straints from colliders are more model-dependent than those from the absence of dinucleon decay. consider- ing only the constraints from dinucleon decay, additional baryons, e.g., Ω c ∼ (ssc), Λ b ∼ (udb), and Ξ b ∼ (usb), become viable candidates for baryogenesis via their os- cillation. an interesting avenue for future work would be constructing models that are less constrained by collider experiments while preserving a large baryon oscillation rate. interesting signatures of this scenario could be present in the large dataset of the upcoming belle ii experi- ment. if the lightest majorana fermion is sufficiently light, one possible signature would be decays of heavy flavor hadrons that violate baryon number and involve missing energy. additionally there could be heavy fla- vor baryons that oscillate into their antiparticles at po- tentially measurable rates. exploring the experimental prospects of this model at high luminosity, lower energy colliders in more detail will be left for future work. constraints from the lhc and the lack of dinucleon decay observation are quite important, suggesting the possibility of the detection of a signal in one or both areas. dinucleon decays are a more model-independent consequence of this scenario, and because of the require- ment of baryon number violation involving heavy flavors, it is likely to assume that dinucleon decay to kaons would be dominant. in the case of the lhc, a particular com- bination of signals in dijet resonances (singly and pair produced) along with an excess in jets plus missing en- ergy should be expected. we should mention in this case that a long-lived neutral particle, χ , that decays hadron- ically is a generic prediction of this model. the typical χ decay length is in the range of − m, which could be well probed by the mathusla detector that was re- cently proposed. the signal of a long-lived but unstable particle at this experiment could help disentangle this scenario from others that lead to excesses in jets plus missing energy. acknowledgments we would like to thank brian batell, kristian hahn, and ahmed ismail for useful conversations. the work of dm is supported by pitt pacc through the samuel p. langley fellowship. the work of tn is supported by spanish grants fpa - -p and sev- - (mineco), and prometeoii/ / (generalitat valenciana). the work of an and ka was supported in part by the department of energy under grant number de-sc . 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page of original research read online: scan this qr code with your smart phone or mobile device to read online. authors: peter-ben smit , , rianne de heide , affiliations: department of texts and traditions, faculty of theology, vrije universiteit, amsterdam, the netherlands institute of old catholic theology, faculty of theology, university of bern, bern, switzerland department of new testament studies, faculty of theology, university of pretoria, tshwane, south africa statistical science group, mathematical institute, leiden university, leiden, the netherlands machine learning group, centrum wiskunde and informatica, amsterdam, the netherlands corresponding author: peter-ben smit, p.b.a.smit@vu.nl dates: received: june accepted: jan. published: mar. how to cite this article: smit, p-b. & de heide, r., , ‘god, the beautiful and mathematics: a response’, hts teologiese studies/ theological studies ( ), a . https://doi.org/ . /hts.v i . copyright: © . the authors. licensee: aosis. this work is licensed under the creative commons attribution license. introduction in his contribution ‘god becomes beautiful … in mathematics’, kessler ( ) argues that relation rudolf bohren’s list of four areas where god’s beauty (or rather: god’s becoming beautiful in the creation through work of the spirit) can be found should be extended with a fifth one: mathematics, in addition to creation, culture and arts, history and the church also mathematics can be seen as a place where god becomes beautiful, a proposal, which rests on an aesthetic interpretation of mathematics. in this response, we would like to argue that ( ) the extension of bohren’s list that kessler argues in favour of is superfluous (as is, in fact, indicated by himself) and ( ) that kessler makes a number of assumptions about (the philosophy of) mathematics that cannot be sustained when taking into consideration the current state of the field. the result of our consideration of kessler’s argument is an interdisciplinary contribution to the discussion about the relationship between mathematics and theology, which seeks to push the debate into direction of a more careful consideration of mathematics as an area in which god’s beauty may become apparent in relation to other such areas, as far as theology is concerned, and a more precise treatments of mathematics, its philosophical underpinning and disciplinary self-understanding as such, which is a precondition for the crafting of any meaningful connection between it and other disciplines, such as theology. four or five areas of god’s beautification? whether or not one should extend bohren’s helpful list of areas in which god may become beautiful – in the sense of becoming concrete, ‘practical’ – through the work of the spirit – thereby overcoming the ugliness of sin in these various realms – depends on one’s understanding of these areas, which seem to be consist of two pairs: nature and culture on the one hand and history and the ‘gemeinde’ on the other. ( ) when it comes to creation, bohren emphasises the process of creation and the excess of beauty in creation, in particular: nature, on the one hand and god’s justification of the beauty of creation (i.e. nature) on the other (i.e. by calling creation ‘good’); yet, this is more than superficial romanticism or an attempt to provide proof for god’s existence out of creation – it is all a question of faith and therefore about discerning god’s becoming beautiful in the ongoing creation of nature, which can be seen as echoing god’s own beauty liturgically (without ignoring ugliness and hurt that is also part of nature – here bohren follows lines of thought of teilhard de chardin; cf. bohren : – ). ( ) in a similar way, bohren understands god’s beautification in human culture and art: ‘gottes praktisch-werden ist ein schön-werden in und durch die schöpfung des menschen, ist ein schön-werden in kultur und kunst’ (bohren : ) in a sense, bohren repeats here with regard to humankind what he has already said about the rest of creation; this agrees with the distinction between nature and culture in his list. ( ) regarding god’s becoming beautiful in history, bohren takes an overarching perspective on the history of the world that goes beyond human culture per se (one could argue, although, that the history of the volker kessler (‘god becomes beautiful … in mathematics’ – hts ) argues two points to rudolf bohren’s list of four areas where ( ) god becomes beautiful should be extended with a fifth one: mathematics and ( ) mathematics can be argued as a place where god becomes beautiful. in this response, we would like to argue that ( ) the extension of bohren’s list that kessler argues in favour of is superfluous and ( ) that kessler makes a number of questionable assumptions about (the philosophy of) mathematics. by arguing against kessler, we intend to make an interdisciplinary contribution to the discussion about the relationship between mathematics and theology by pushing the debate into direction of a more careful consideration of mathematics as an area in which god’s beauty may become apparent. contribution: contributing to the interdisciplinary exploration of theology in hts teologiese studies/theological studies, this article further develops the consideration of the fundamental theological topic of god, the beautiful and mathematics as it was proposed in this journal by volker kessler, by discussing it from a systematic theological and mathematical perspective. keywords: god; beautiful; culture; mathematics; philosophical underpinning. god, the beautiful and mathematics: a response read online: scan this qr code with your smart phone or mobile device to read online. http://www.hts.org.za https://orcid.org/ - - - x https://orcid.org/ - - - mailto:p.b.a.smit@vu.nl https://doi.org/ . /hts.v i . https://doi.org/ . /hts.v i . http://crossmark.crossref.org/dialog/?doi= . /hts.v i . =pdf&date_stamp= - - page of original research http://www.hts.org.za open access world can be subsumed under the nature/culture categories – or vice versa), indicating that also in the events of history, god’s (salvific) becoming practical and beautiful can be discerned. ( ) in analogy to the related realms of nature and culture, bohren also treats the church (‘gemeinde’) in relation to history: what can be said about the history at large can also be said about the particular of israel and the church, together god’s ‘gemeinde’, god’s becoming practical in history cannot be reduced to god’s working in the ‘gemeinde’, yet it is also there and needs to be discerned in faith. based on this background, it becomes difficult to argue that mathematics should be a distinct field in which god becomes beautiful. the reason for this is quite simple: one would have to argue that mathematics is distinct from either the realm covered by the pair ‘nature and culture’ or by the pair ‘history and gemeinde’. that mathematics may not be part of the ‘gemeinde’ would make sense – to a certain extent, at least – that it is not a broader historical development would be hard to deny, however – even harder to deny is that mathematics is a distinctly human cultural achievement, which, depending on one’s view of the matter, has to do with discovering the inner workings of nature and thereby of nature’s beauty (as an echo of god’s beauty or not). in fact, it seems that this is also indicated by kessler himself. as what has been argued in this section, in fact finds additional support in kessler’s ( ) own conclusions, where he states: thus, the mathematician contributes to the visibility of god’s beauty in his creation. this would correspond with bohren’s viewpoint that god becomes beautiful in the creation (bohren : – ). if, however, we follow the minority’s viewpoint, namely that mathematics is a creation, then it would correspond with bohren’s chapter ‘culture and arts’. in that chapter, bohren ( : ) argues that god becomes beautiful by and through human creations in culture and arts. thus, in both cases, we can conclude: god becomes beautiful in mathematics. (p. ) depending on one’s view of the achievement of a mathematician – discovering creation or creating something (cultural) – mathematics can be quite happily subsumed under one of bohren’s other categories, that is, either his first one (creation) or his second one (culture). therefore, a first and somewhat formal conclusion can be that the identification of mathematics as a distinct realm of god’s becoming practical (in the sense of ‘beautiful’) is quite superfluous. questions of mathematics and philosophy kessler states ‘in mathematics, there is a striking link between beauty and truth’, and that ‘mathematicians simply believe in truth’, generalising from quotes of several more or less famous mathematicians. we will take a closer look at concepts that kessler introduces, and see that the matter is more complicated than it might appear. the subject matter of kessler’s article gives rise to fundamental questions such as: ‘what is mathematics about?’, ‘what is mathematical truth?’, ‘what do mathematical statements mean?’, ‘what is the source of mathematical knowledge?’, etc. some of these questions have been asked for many centuries, and are nowadays, after the substantial compartmentalisation of academia of the past century, being studied in the field of philosophy of mathematics. in the following, we challenge two of kessler’s core ideas: first, the platonistic worldview of working mathematicians, which he takes as a point of departure in his argument. secondly, we explore the apparent simplicity of the mathematical method: logical reasoning based on axiom systems, which is also of importance to kessler. we take a closer look at complications that arise both with axiom systems and with logical reasoning, in order to illustrate further the complexity of mathematics, which needs to be considered when making arguments about mathematics and beauty. firstly, platonism amongst mathematicians will be considered. mathematical platonism can be defined as holding the following three theses: ( ) mathematical objects exist, ( ) they are abstract and ( ) they are independent of intelligent agents (linnebo ). let us start with one of kessler’s arguments in favour of a platonistic view of the mathematical world: natural language. mathematicians often use the phrase: ‘i discovered this theorem’ (implying abstract existence of the theorem independent of the mathematician), although the parlance changes when talking about designing or inventing algorithms. the debate over the implicit meaning of using specific words to the mathematical worldview of the speaker is not novel: plato himself already complained about the vocabulary of mathematicians writing about geometry (plato, book of republic). geometry is an interesting subject when we discuss the language mathematicians use, which either would imply external existence of mathematical objects (discovery), or human creation (design, invention). as described in (shapiro : ), most sources of ancient geometry (including euclid’s elements) use constructive, dynamic language. today, we still talk about drawing lines, constructing angles, applying functions, rotating and translating figures. this speaks against a platonistic worldview. whilst it might be true that superficially, many mathematicians want to believe that the objects they study are real, hersch ( : ) famously states that they know better: (...) the working mathematician is a platonist on weekdays and a formalist on sundays. that is, when he is doing mathematics, he is convinced that he is dealing with an objective reality whose properties he is attempting to determine. but then, when challenged to give a philosophical account of this reality, he finds is easiest to pretend that he does not believe in it after all. a study into the world views of university mathematics teachers, asking the ‘sunday question’ (grigutsch & törner ), confirms this. we do not disagree with kessler that the platonic view (to be more precise: realism in ontology (shapiro )) is common amongst working mathematicians, but in hersh’ ( ) words, this is an ‘inarticulate, half- conscious platonism’, as it brings the mathematician in http://www.hts.org.za page of original research http://www.hts.org.za open access trouble when questions are asked how the platonic abstract world relates to our physical world. when asked these ‘sunday questions’, mathematics reduces to rules for manipulating formulas without any reference to their meaning: formalism, one of the ‘big three’ (shapiro ) major philosophical positions in the past century (the other two being logicism and intuitionism). in other words, it is in appearance only that mathematicians are platonists, in reality, they are often formalists, in particular when they face the philosophical questions that one is forced to address when committing to a platonist position in the philosophy of mathematics. this strongly cautions against taking platonism as a representative point of departure in the philosophy of mathematics for making claims about the relationship between mathematics and theology. secondly, the concept of axiom systems is to be addressed. in his article, kessler refers to the method of mathematics as starting with an axiom system, proceeding to further propositions by logical reasoning based on this axiom system – this is by the way a typical description of a formalistic approach. such a system of axioms together with rules in order to generate new propositions (with additional conditions) is commonly referred to as a formal system. kessler further writes that mathematical axiom systems are assumed not to give rise to contradictions, that is, they are assumed to be logically consistent (furthermore, heisenberg is cited pointing to the coherence of axiom systems; coherence is usually characterised encompassing logical consistency). such formal systems arose in the context of hilbert’s programme of providing a foundation for mathematics. kessler describes that his ‘search for eternal, provable truth’ led him to the discipline of mathematics and assumes that this is typical of mathematicians. if we combine this view with working with formal systems as a foundation for (the method of) mathematics, the following famous theorems of the mathematician and philosopher gödel ( ) might come as a disappointment: when f is a consistent formal system (sufficiently rich, see shapiro ch. . ), ( ) there are statements in the language of f that can neither be proved or disproved in f (gödel’s first incompleteness theorem), and ( ) the consistency of f cannot be proved in f itself (gödel’s second incompleteness theorem). gödel’s two theorems show the limits of provability in axiomatic systems, which raises the question how ‘eternal, provable truth’ that can be reached via provability in some deductive system, can be compatible with gödel’s theorems. this depends on how we interpret kessler’s statement that his search for eternal, provable truth led him to mathematics, which we could view as realism in truth-value (shapiro ). a truth-value realist, who views that every mathematical statement is objectively either true or untrue, would have to conclude that truth goes beyond provability in any axiomatic system, and the next question for the realist would be to define what this ‘other type of truth’ consists of. much has been written about this since gödel’s publications in , and it would be impossible to cover every point of view, our point here is merely to illustrate how much more there is to kessler’s casual mentioning of the deceptively uncomplicated reduction of truth-finding in mathematics to having consistent axiom systems together with logical reasoning – see the upcoming paragraph. again, kessler’s argument seems to be based on an oversimplified view of what mathematics and its philosophical reflection entails. finally, having said something about those axiom systems, it is possible to also address briefly what ‘logical reasoning’ is? the answer is more plural than one might expect. one of the big three (terminology of shapiro [ ]) philosophical positions on mathematics is intuitionism, and if one adheres to this view, it has extensive implications for one’s practice of mathematics. the classical logic is replaced by an intuitionistic logic, which does not contain the law of the excluded middle: a law that states that for any proposition, either the proposition or its negation is true. let us look at what happens with the indirect proof or reductio ad absurdum that kessler brings up. suppose we want to derive a contradiction from the proposition not-a, and we successfully conclude: not-not-a. the intuitionist cannot conclude the truth of a, whereas a classical logician can (illustrated by kessler’s example of the existence of infinitely many primes). so also the matter of what logic we should use when we do mathematics turns out to be more complicated than kessler makes it appear. when only considering mathematics superficially, it seems to be this very clear-cut discipline where objective truth follows from well-defined axiom systems and logical deductions. here, we have shown that when we take a closer look, many questions and problems arise; problems that have been considered by many mathematicians and philosophers of mathematics in the history – ancient and recent. our findings are by no means novel, see for example (ernest ), who concludes that ‘mathematical certainty is a myth’. concluding observations in the given considerations of kessler’s argument, we have engaged in a debate with volker kesser and his contribution to the relationship between mathematics and theology, in particular the aesthetic proposal for a practical theology of rudolf bohren. in doing so, we have argued, as a contribution to furthering reflection on the relationship between these two disciplines, that ( ) the addition of mathematics as a fifth area where god’s beauty can become apparent is not necessary, given that mathematics can well be seen as being covered by one or two of bohren’s other areas, and ( ) that kessler does not discuss in detail the current state of research in the field of philosophy of mathematics, and in not doing so, the view of mathematics in his article is not sufficiently represented to function as a starting point for crafting a bridge between this and other disciplines. research into the relationship between theology and mathematics remains inviting but it would be necessary to do so on the basis of the full inclusion of current positions in the philosophy of mathematics and in a manner that more fully considers the relationship between mathematics and human culture and history, at least when a connection is to be established with bohren’s paradigm. http://www.hts.org.za page of original research http://www.hts.org.za open access acknowledgements competing interests the authors have declared that no competing interests exist. authors’ contribution all authors contributed equally to this work. ethical considerations this article followed all ethical standards for a research without direct contact with human or animal subjects. funding information this research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. data availability data sharing is not applicable to this article as no new data were created or analysed in this study. disclaimer the views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of any affiliated agency of the authors. references bohren, r., , dass gott schön werde: praktische theologie als theologische Ästhetik, kaiser, münchen. ernest, p., , ‘the problem of certainty in mathematics’, educational studies in mathematics ( ), – . https://doi.org/ . /s - - -x gödel, k., , ‘Über formal unentscheidbare sätze der principia mathematica und verwandter systeme i’, monatshefte für mathematik und physik , – , english translation in: idem, collected works i: publications – , pp. – , oxford university, oxford, . https://doi.org/ . /bf grigutsch, s. & törner, g., , world views of mathematics held by university teachers of mathematics science, fachbereich mathematik, ud. hersh, r., , ‘some proposals for reviving the philosophy of mathematics’, advances in mathematics ( ), – . https://doi.org/ . / - ( ) - hersh, r., , what is mathematics, really?, oxford university press, oxford. kessler, v., , ‘god becomes beautiful … in mathematics’, hts teologiese studies/ theological studies ( ), a . https://doi.org/ . /hts.v i . linnebo, Ø., , ‘platonism in the philosophy of mathematics’, in e.n. zalta (ed.), the stanford encyclopedia of philosophy, spring edition, viewed march , from https://plato.stanford.edu/archives/spr /entries/platonism-mathematics. shapiro, s., , thinking about mathematics: the philosophy of mathematics, oxford university press, oxford. http://www.hts.org.za https://doi.org/ . /s - - -x https://doi.org/ . /bf https://doi.org/ . / - ( ) - https://doi.org/ . /hts.v i . https://plato.stanford.edu/archives/spr /entries/platonism-mathematics the perceived beauty of regular polygon tessellations symmetrys s article the perceived beauty of regular polygon tessellations jay friedenberg department of psychology, manhattan college, riverdale, ny , usa; jay.friedenberg@manhattan.edu; tel.: + - - - received: june ; accepted: july ; published: august �� abstract: beauty judgments for regular polygon tessellations were examined in two experiments. in experiment we tested the three regular and eight semi-regular tilings characterized by a single vertex. in experiment we tested the demi-regular tilings containing two vertices. observers viewed the tessellations at different random orientations inside a circular aperture and rated them using a numeric – scale. the data from the first experiment show a peak in preference for tiles with two types of polygons and for five polygons around a vertex. triangles were liked more than other geometric shapes. the results from the second experiment demonstrate a preference for tessellations with a greater number of different kinds of polygons in the overall pattern and for tiles with the greatest difference in the number of polygons between the two vertices. ratings were higher for tiles with circular arrangements of elements and lower for those with linear arrangements. symmetry group p m was liked the most and groups cmm and pmm were liked the least. taken as a whole the results suggest a preference for complexity and variety in terms of both vertex qualities and symmetric transformations. observers were sensitive to both the underlying mathematical properties of the patterns as well as their emergent organization. keywords: tessellations; tiles; tilings; polygons; symmetry; beauty; aesthetics; decorative pattern . introduction we are surrounded by geometric patterns. these can be seen in the tiles on floors, in wallpaper patterns on our walls, and in the clothes we wear. they are also found in decorative artwork that adorns the outside of buildings and in signs, advertising, and in graphic and web design [ ]. all major cultures have produced and enjoyed them [ , ]. what is the allure of these patterns? why have we been compelled to create and view them over the course of human history? in this paper, we will examine these questions by looking at a group of tessellations, also known as tilings, whose geometric and mathematical properties are well defined. we will use these properties to predict and help explain their aesthetic appeal. in what follows, we outline the different types of tessellations, showing that they can be categorized by the types of polygons they contain, the way they are arranged around defining vertices, and their symmetry properties. a plane tessellation is a pattern made up of one or more shapes, completely covering a surface without any gaps or overlaps [ , ]. all tessellations can be extended in the plane infinitely in every direction. tilings are made up of closed figures that form the overall design. closed figures all have a perimeter and area. the simplest type of closed figure is a polygon, made of straight-line segments and defined by number of sides and angles. any regular triangle, quadrilateral, or hexagon will tessellate the plane by itself. regular in this instance means that all sides and angles are equal. regular pentagons, heptagons, or any other regular polygon will not tile the plane. these three types of tilings are called regular. any other tiling of the plane by regular polygons must occur through a combination of two or more polygons. there are eight such types, known as semi-regular tilings. every regular tiling is defined by a vertex point. this vertex is surrounded by a group of polygons that in sequence serve as a signature for its identification. the first group of regular and semi-regular symmetry , , ; doi: . /sym www.mdpi.com/journal/symmetry http://www.mdpi.com/journal/symmetry http://www.mdpi.com http://www.mdpi.com/ - / / / ?type=check_update&version= http://dx.doi.org/ . /sym http://www.mdpi.com/journal/symmetry symmetry , , of tilings are defined by one vertex point and are studied in experiment (shown in figure ). these are known as -uniform patterns. the second group of regular tilings are defined by two different vertices and are explored in experiment . all of these tessellations are edge-to-edge, meaning the polygons share common edges and vertices. however, it is possible to tessellate the plane with regular polygons that are not arranged this way. these are called non-congruent tilings. in addition, one can tile the plane with polygons that are not regular and do not have equal sides and angles. these tessellations are referred to as irregular. non-congruent and irregular tilings will not be examined in the current study. regular and semi-regular tilings are characterized by a set of rules first formulated in by the rev. mr. jones [ ]. the first is that these tilings must have polygon angles meeting at a vertex that sum to exactly ◦. the second is that they must have at least three polygons and no more than six meeting at each vertex. the third is that no semi-regular tiling can have four different types of polygons meeting at a vertex. the study provides a more extended and technical discussion of these rules [ ]. the polygons in a shape are clearly visible and may have an impact on their perceived beauty. people may prefer certain polygons over others or may prefer patterns with certain types of vertices. another way to characterize tessellations is by their symmetry properties [ ]. there are four basic symmetry transformations that when applied can transform a shape in a tessellation upon itself or another identical shape. these are translation, reflection, rotation, and glide reflection. in translation a shape is simply moved. in reflection it is mirror-imaged about an axis. in rotation it is rotated or spun about a point. when shapes are rotated, they can be described by their order of rotation. if a shape has an order of rotation of it has -fold rotational symmetry and can be rotated into congruence with itself by a ◦ spin. order is -fold ( ◦), order is -fold ( ◦), and order is -fold, ( ◦). in glide reflection, the shape is both translated and then reflected. all of these symmetries are present in polygon tessellations. when looking at tile patterns, one can consciously or subconsciously perceive these transformations and so they may play a role in determining their visual beauty. despite their ubiquity, there is remarkably little research on the aesthetic qualities of tessellations. much of the work in this area has focused on individual polygons and dates from the th and th centuries [ – ]. according to a recent study, participants judged the perceived attractiveness for all basic types of squares and quadrilaterals [ ]. there was a preference for regularity. triangles with smaller side length standard deviations (more equal sides) were found to be more beautiful. observers in that study liked equilateral triangles more than any other type of triangle. the same result was found for quadrilaterals. as four-sided shapes become more regular, they are preferred more. symmetry also predicted liking for these polygons but could not completely account for all of the ranked preferences. symmetry is a major property affecting preference for two-dimensional geometric pattern. in one study, participants were asked to judge the subjective beauty of novel graphic patterns [ ]. symmetry correlated highly with aesthetic assessments as did stimulus complexity. however, they also found individual differences, in which some of the participants preferred non-symmetric patterns. their data fit both a group model and an individual case model, indicating universal and particular tastes. another study similarly found individual differences in preferences for single polygons [ ]. recent work found that geometric symmetrical patterns are used most frequently in life, but are also produced spontaneously in the lab [ ]. in addition, they are rated significantly more attractive than random patterns. in prior work, the researchers looked at the spatial distribution characteristics of “crazy quilts” and ordered quilt patterns [ ]. crazy quilts, first created in the s, are intended to appear haphazard and unstructured. they found that these two quilt types belong to separate classes, the first corresponding to randomness and the second to ordered production methods. the ordered patterns were based on regular pattern motifs that repeated in the designs. preference for random patterns however, appear to be an exception, with most decorative arts of this nature being highly ordered [ ]. in a different study, researchers interviewed six fourth-grade children as to how they conceptualized tessellations and compared their responses with those of two adult mathematicians [ ]. preference tasks showed the students had a slight preference for symmetric over random patterns but judged on a symmetry , , of number of other criteria such as color, complexity and motif. although children agreed on the criteria, there were substantial individual differences on which criteria determined appeal for a given pattern. the children rarely created random tilings if they could make a symmetric one and often pointed out the “patterns” in random tilings they had constructed. the mathematicians disliked tessellations with only one interesting dimension and thus seemed to have a preference for complexity. they also enjoyed tessellations that surprised them or were thought provoking. in addition, mathematicians preferred tilings whose aesthetic qualities aligned with those identified by previous researchers. children focused on some themes the adults did not like variety of color and real-world connections. this study shows that even young children have a sense of aesthetics and that they can apply this to both evaluating and creating tessellations. the current study is exploratory rather than confirmatory in nature. we thus make no a priori predictions about which tessellations will be considered more beautiful than others. this is because each tiling differs considerably in the kind and complexity of both the polygons that make it up and the symmetry transformations that map these polygons onto themselves and one another. we instead analyze a number of polygon and symmetry features to see if these can predict preference. the main variables measured are the kind of polygons, the number of polygons around each vertex, their symmetry group and lattice type, the kind of symmetries, their rotation order, and other characteristics, such as the location of rotation centers. in experiment , we look at the regular and semi-regular tile types defined by a single vertex. in experiment , we test the types defined by two vertices, sometimes called demi-regular tessellations. . experiment . . participants thirty-two manhattan college undergraduates participated to fulfill a class requirement. there were males and females. vision was normal or corrected to normal. average age of the students was approximately years. all participants volunteered to participate and signed a consent form prior to running in the experiment. american psychological association ethical standards and data confidentiality were adhered to. . . stimuli all of the tiling patterns used in both experiments are regular, meaning they consist only of regular convex polygons whose sides and angles are equal. the types of polygons that occur in these tessellations are equilateral triangles, squares, hexagons, octagons, and dodecagons. all of the tiles are edge-to-edge, in which every side of every tile is an edge of the tiling, and each side of a tile is also a side of precisely one other tile. there are distinct edge-to-edge tilings by regular polygons. these are shown in figure . symmetry , , of symmetry , , x for peer review of figure . the types of regular polygon tessellations shown in experiment . the black dot indicates a defining vertex. one of these patterns, (f a or . ) has an enantiomorphic, or mirror image form. the two versions of these are difficult to distinguish perceptually and so only one of these versions was included in the study. each of these regular tessellations is identified by a unique type of vertex surrounded by a circular sequence of polygons. for example, the purely triangular tiling f is defined by the vertex ( ), in the expanded notation ( . . . . . ) because the vertex is surrounded by figure . the types of regular polygon tessellations shown in experiment . the black dot indicates a defining vertex. one of these patterns, (f a or . ) has an enantiomorphic, or mirror image form. the two versions of these are difficult to distinguish perceptually and so only one of these versions was included in the study. each of these regular tessellations is identified by a unique type of vertex surrounded by a circular sequence of polygons. for example, the purely triangular tiling f is defined by the vertex ( ), in the expanded notation ( . . . . . ) because the vertex is surrounded by six equilateral triangles. symmetry , , of the pattern f or ( . . . . ) has a vertex surrounded by two equilateral triangles, a square, an equilateral triangle, and a square. patterns f , f , and f ( ), ( ), and ( ) are labeled as regular tilings or tessellations. these three are regular if the symmetry group of the tiling acts transitively on the flags of the tiling [ ]. a flag is a triple consisting of a mutually incident vertex, edge, and tile of the tiling. for every pair of flags there is a symmetry operation mapping the first flag to the second. the remaining eight tilings are known as archimedean, uniform, or semi-regular tilings. these are characterized by vertex-transitivity, meaning that for every pair of vertices, there is a symmetry operation mapping the first vertex to the second. in vertex-transitivity each vertex is surrounded by the same kinds of face in the same or reverse order and with the same angles between corresponding faces. each pattern can also be categorized by its symmetry group that lists the type of symmetry operations mapping motifs or elements of the pattern onto themselves and one another. for example, the triangular tiling ( ) belongs to group p m, characterized by rotations of orders ( ◦), ( ◦), and ( ◦), as well as reflections and glide-reflections. the pattern f or ( · · · ) belongs to symmetry group p g. this has reflections and rotations of orders and and four axes of reflection. table lists the notations, symmetry group and polygon features for each of the patterns, listed by the preference rank determined in experiment . table lists the properties of each symmetry group for the tilings used in both experiments. table . notations, symmetry group and polygon properties for the tilings of experiment . file notation standard notation expanded notation symmetry group polygon types polygons in pattern polygons around vertex preference ranking f . . . . . . . p g ts f a . . . . . p th f a . . . . . cmm ts f . . . . . . p m tsh f . . . . . p m t f . . . . . . p m th f . . . p m so f . . p m h f . . . . p m shd f . . . p m s f . . . p m td polygon types: (t = triangle, s = square, h = hexagon, o = octagon, d = dodecagaon). table . symmetry group properties for the tilings in experiments and . symmetry group lattice symmetry types rotation orders other features cmm rhombus rf, rt rf in two perpendicular directions p g square rf, rt, gl , rf in two perpendicular directions order rt centers are at the intersections of rf axes p m square rf, rt, gl , rf lines intersect at ◦ all rt centers lie on rf axes p hexagon rt , , no rf; no gl p m hexagon rf, rt, gl , , rf in six directions possibly the most complex pgg rectangular rt, gl no reflections. gl in two perpendicular directions rt centers not located on gl axes pmm rectangular rf, rt rf in two perpendicular directions rt centers at the intersection of rf axes symmetry types: (rf = reflection, rt = rotation, gl = glide reflection). symmetry , , of . . procedure the tilings were presented within a circular aperture that measured cm in diameter. this was done to prevent familiarity and any framing effects where the lines in the pattern may have aligned with prominent orientations such as gravitational vertical or the sides of the computer monitor. five versions of each tiling were generated. each version corresponded to a different random orientation. this yielded trials per block. six blocks were presented for a total of trials in an experimental session. trial order within a block was randomized. observers were given as much time as they needed to respond. on average a session took about min to complete. participants judged the beauty of each tiling using a -point rating scale. a “ ” on the scale corresponded to “very beautiful”, while a “ ” corresponded to “very ugly”. the students were encouraged to use the entire range of the scale, including “ ”, which indicated a neutral response of no preference. they used the number keys that ran across the top of the computer keyboard. participants were additionally instructed that there was no right or wrong answer and to rate the tessellations in any manner they wanted. this was done in order to reduce experiment-induced judgment criteria or demand characteristics. if any number other than – was entered, the participant would not be able to advance to the next trial. in this case, they were told to re-enter an appropriate value. following the experiment, all participants completed a questionnaire to compile basic demographic information. they were also asked to respond personally as to what tilings they liked and what features of the patterns may have affected their responding. they read a written debrief form and any remaining questions they had concerning the study were answered by the research assistant. . . results and discussion any responses that exceeded seven seconds were considered moments of inattention and removed from the data prior to analysis. these constituted about less than % of all the responses. beauty ratings were normalized by the formula of (score − min)/(max − min) where the minimum and maximum were determined across subjects. reaction time measures were also taken but did not produce any interpretable results so are not reported here. one-way analysis of variance (anova) tests were performed for number of unique polygons in the overall tile pattern (polygons in pattern), number of polygons around the vertex (polygons around vertex), symmetry group (symmetry group) and for type of tile pattern (tile pattern). there was a significant effect of polygons in pattern, f( , ) = . , p < . , with peak responding found for tilings with two polygons (figure ). effect size as eta squared was (η = . ). polygons around vertex was also significant, f( , ) = . , p < . , (η = . ) with peak mean beauty ratings for five polygons (figure ). symmetry group was analyzed next, f( , ) = . , p < . , (η = . ) with the highest rating for tiles with group p g (figure ). finally, we looked at mean ratings for tile pattern, f( , ) = . , p < . , (η = . )with peak responding found for tile f ( · · · ). this is shown in figure . symmetry , , of symmetry , , x for peer review of figure . average normalized beauty ratings based on the total number of different polygons in the tessellations for experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for the number of different polygons around the defining vertex for the tessellations in experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings based on the total number of different polygons in the tessellations for experiment . error bars indicate ± standard error of the mean. symmetry , , x for peer review of figure . average normalized beauty ratings based on the total number of different polygons in the tessellations for experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for the number of different polygons around the defining vertex for the tessellations in experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for the number of different polygons around the defining vertex for the tessellations in experiment . error bars indicate ± standard error of the mean. symmetry , , of symmetry , , x for peer review of figure . average normalized beauty ratings for the symmetry groups of the tessellations in experiment . error bars indicate ± standard error of the mean. see table for the defining features of each group. figure . average normalized beauty ratings for each of the tile pattern types in experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for the symmetry groups of the tessellations in experiment . error bars indicate ± standard error of the mean. see table for the defining features of each group. symmetry , , x for peer review of figure . average normalized beauty ratings for the symmetry groups of the tessellations in experiment . error bars indicate ± standard error of the mean. see table for the defining features of each group. figure . average normalized beauty ratings for each of the tile pattern types in experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for each of the tile pattern types in experiment . error bars indicate ± standard error of the mean. symmetry , , of the results show that participants preferred tiles with the second greatest number of different polygons. one might have predicted a variety effect, in which ratings increased continuously on this variable, but this was not obtained suggesting a moderate preference for polygonal variety. preference also increased with number of polygons around the vertex, but only up to five. this may indicate a limit to liking how tightly packed a pattern is with polygons, as polygon density increases with number around the vertex. average angle and size of polygons around the vertex are also correlated with number. the greater the number the lower the average angle and the smaller in area the polygons become. figure shows mean beauty ratings by each of the tessellation types. these were analyzed in terms of the type of polygons they contained to see if participants preferred certain polygons. looking at ranked preference in table we see that tilings with triangles dominated the top of the list. excluding f tiles triangles occupied the top six positions. tiles with dodecagons (f and f ) were near the bottom of the list, at positions nine and eleven respectively. these preferences were independent of the number of different polygons around the vertex. preference for symmetry groups ranked high to low was as follows: p g, p , cmm, p m, and p m. we can evaluate these rankings looking at some of the basic symmetry properties shown in table . each tiling is characterized by an underlying lattice type. each lattice type has a geometric cell structure that contains the tiling’s basic pattern or motifs and which when fit together will tile that pattern to completely fill the two-dimensional plane. lattice type did not predict rankings. the p g tiling has a square lattice and was preferred the most. the p m tiling also has a square lattice but was preferred the least. we can also examine the type of symmetry operations in each tiling. it was not the case that tessellations with more symmetries were rated higher. tile p g has rotation, reflection, and glide-reflection and was liked the most. but tile p m also has these three symmetries and was ranked lowest. rotation order additionally did not predict liking. tiles with the greatest number of rotation orders ( , , ) were not liked more than those that had only two ( , ) or one ( ) order of rotation. tile p and tile p m have three rotation orders but were not liked equivalently, ranked at positions two and four respectively. one explanation for tile p g’s popularity is that it has reflections in two perpendicular directions and order rotation centers that are at the intersections of reflection axes. so, the type and location of rotation centers for this pattern may be meaningful. . experiment the first experiment examined the regular and semi-regular tiles. these are designated as -uniform because they are characterized by a single vertex. however, there is another class of regular tiles that are -uniform, meaning they are defined uniquely by two different vertices. there are distinct types of -uniform edge-to-edge tilings by regular polygons. these are shown in figure with the two dots indicating the vertices. these patterns allow us to potentially replicate and generalize the findings from experiment to a larger class of similar patterns. they also allow us to examine the relationship between two vertices and how those might affect beauty judgments. . . participants thirty-three manhattan college undergraduates participated to fulfill a class requirement. there were males and females. vision was normal or corrected to normal. average age of the students was approximately years. all participants volunteered to participate and signed a consent form prior to running in the experiment. american psychological association ethical standards and data confidentiality were followed. . . stimuli all of the tiling patterns were again regular containing polygons of equal sides and angles. this time however there were tilings characterized by having two defining vertices. each of these symmetry , , of are shown in figure . table lists the notation, symmetry group, and polygon features for these patterns, listed by their order of preference from the second experiment data. table lists the properties for each of the symmetry groups including the two new groups of pgg and pmm. it should be noted that there are several tilings among the two-uniform grouping that have equivalent vertex designations but that differ in their appearance. these differences are explored in the data analysis. symmetry , , x for peer review of patterns, listed by their order of preference from the second experiment data. table lists the properties for each of the symmetry groups including the two new groups of pgg and pmm. it should be noted that there are several tilings among the two-uniform grouping that have equivalent vertex designations but that differ in their appearance. these differences are explored in the data analysis. figure . the types of regular polygon tessellations shown in experiment . the two black dots indicate the defining vertices. symmetry , , of table . notations, symmetry group and polygon properties for the tilings of experiment . file notation standard notation symmetry group polygon types polygons in pattern polygons vertex polygons vertex preference ranking f g ˆ . ˆ ; . . . p m tsh f c ˆ . . . ; . . . p m tsh f d ˆ ; ˆ . . . p m ts f f . ˆ . ; . . . p m tsh f a . . . ; . . p m tshd f b ˆ ; ˆ . . p m tsd f d ˆ ; ˆ . ˆ p m th f . . . ; . ˆ p m tsd f b ˆ . ˆ ; ˆ . . . p g ts f e ˆ . ; ˆ . ˆ cmm th f c ˆ . ˆ ; ˆ . . . pgg ts f c ˆ ; ˆ . p m th f g ˆ . ˆ ; . . . p th f c ˆ . . . ; . . . pmm th f d ˆ ; ˆ . . . pmm ts f f . ˆ . ; . . . cmm tsh f a . . . ; . . pmm tsh f b ˆ ; ˆ . . cmm ts f d ˆ ; ˆ . ˆ cmm ts f . . . ; . ˆ cmm ts polygon types: (t = triangle, s = square, h = hexagon, o = octagon, d = dodecagaon). . . procedure the procedure was identical to that in the first study. the tilings were presented within the same-sized circular aperture. five versions of each tiling were generated. each version corresponded to a different randomly determined orientation. this yielded trials per block. three blocks were presented for a total of trials in an experimental session. trial order within a block was randomized. observers were given as much time as they needed to respond. on average a session took about min to complete. participants judged the beauty of each tiling using the same -point rating scale and the same set of instructions described previously. following the experiment, all participants completed a demographic questionnaire and debrief form. . . results and discussion any responses that exceeded seven seconds were considered moments of inattention and removed prior to analysis. these constituted about less than % of all the responses. beauty ratings were normalized by the formula of (score − min)/(max − min) where the minimum and maximum were determined across subjects. reaction time measures did not produce meaningful results and are not reported. one-way anovas were performed for number of unique polygons in the overall tile pattern (polygons in pattern), the difference in the number of polygons between the two vertices (polygons vertex − vertex , where vertex contained the larger number), the tessellations symmetry group (symmetry group) and for type of tile pattern (tile pattern). there was a significant effect of polygons in pattern, f( , ) = . , p < . , (η = . ) with ratings increasing with the number of polygons (figure ). ratings for the difference in the number of polygons between the two vertex centers was also significant, f( , ) = . , p < . , (η = . ) with mean beauty ratings at a minimum for tilings with equal numbers of polygons and rising as the difference increases (figure ). symmetry group was analyzed next, f( , ) = . , p < . , (η = . ) with the highest rating for tiles with group p m, followed by p m, p g, pgg, p , pmm, and cmm (see figure ). finally, we looked at mean ratings for each of the unique patterns, what we call tile pattern, f( , ) = . , p < . , (η = . ) with peak responding found for four tiles in the f group, intermediate level responding for several tiles in the f group and lowered ratings for some of the f group of tiles. this is depicted in figure . symmetry , , of symmetry , , x for peer review of looked at mean ratings for each of the unique patterns, what we call tile pattern, f( , ) = . , p < . , (η = . ) with peak responding found for four tiles in the f group, intermediate level responding for several tiles in the f group and lowered ratings for some of the f group of tiles. this is depicted in figure . figure . average normalized beauty ratings based on the total number of different polygons in the tessellations used in experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for the difference in the number of polygons between the two defining vertices for the tessellations in experiment . error bars indicate ± standard error the mean. figure . average normalized beauty ratings based on the total number of different polygons in the tessellations used in experiment . error bars indicate ± standard error of the mean. symmetry , , x for peer review of looked at mean ratings for each of the unique patterns, what we call tile pattern, f( , ) = . , p < . , (η = . ) with peak responding found for four tiles in the f group, intermediate level responding for several tiles in the f group and lowered ratings for some of the f group of tiles. this is depicted in figure . figure . average normalized beauty ratings based on the total number of different polygons in the tessellations used in experiment . error bars indicate ± standard error of the mean. figure . average normalized beauty ratings for the difference in the number of polygons between the two defining vertices for the tessellations in experiment . error bars indicate ± standard error the mean. figure . average normalized beauty ratings for the difference in the number of polygons between the two defining vertices for the tessellations in experiment . error bars indicate ± standard error of the mean. symmetry , , of symmetry , , x for peer review of figure . average normalized beauty ratings for the symmetry groups of the tessellations in experiment . error bars indicate ± standard error of the mean. see table for the defining features of each group. figure . average normalized beauty ratings for each of the tile pattern types in experiment . error bars indicate ± standard error of the mean. participants preferred tiles with the greatest number of different polygons. unlike experiment , in this study ratings increased continuously on this variable. in fact, going from – polygons the effect looks quite linear. the results suggest a preference for either complexity or variety of basic polygon shapes. perhaps the difference between the two experiments has to do with the range of polygons presented. when a greater number of types are present, there may be a preference shift towards increased complexity. in this experiment the patterns are categorized based on two vertex centers with different numbers and types of polygons. in order to capture whether participants are sensitive to the figure . average normalized beauty ratings for the symmetry groups of the tessellations in experiment . error bars indicate ± standard error of the mean. see table for the defining features of each group. symmetry , , x for peer review of figure . average normalized beauty ratings for the symmetry groups of the tessellations in experiment . error bars indicate ± standard error of the mean. see table for the defining features of each group. figure . average normalized beauty ratings for each of the tile pattern types in experiment . error bars indicate ± standard error of the mean. participants preferred tiles with the greatest number of different polygons. unlike experiment , in this study ratings increased continuously on this variable. in fact, going from – polygons the effect looks quite linear. the results suggest a preference for either complexity or variety of basic polygon shapes. perhaps the difference between the two experiments has to do with the range of polygons presented. when a greater number of types are present, there may be a preference shift towards increased complexity. in this experiment the patterns are categorized based on two vertex centers with different numbers and types of polygons. in order to capture whether participants are sensitive to the figure . average normalized beauty ratings for each of the tile pattern types in experiment . error bars indicate ± standard error of the mean. participants preferred tiles with the greatest number of different polygons. unlike experiment , in this study ratings increased continuously on this variable. in fact, going from – polygons the effect looks quite linear. the results suggest a preference for either complexity or variety of basic polygon shapes. perhaps the difference between the two experiments has to do with the range of polygons presented. when a greater number of types are present, there may be a preference shift towards increased complexity. in this experiment the patterns are categorized based on two vertex centers with different numbers and types of polygons. in order to capture whether participants are sensitive to the presence of these symmetry , , of centers we took the difference in the number of polygons between them and used this to predict ratings. the results show a clear preference for centers that differ from each other in polygon number. patterns in which the number was the same were liked the least with an upward trend as the difference increased. patterns with different centers are less homogenous so this result could again indicate a preference for variety or complexity. these results show that participants are sensitive to vertices and that they do seem to affect aesthetic judgments. we compared tiles that had equivalent vertex designations but varying similarity. some of these equivalents are nearly identical to one another in appearance while others are more dissimilar. if there is no difference in responding between such equivalents then the underlying vertices play a more important role in determining perceived beauty. if there is a difference between equivalents that is discernible, then surface appearance should be the more important factor. a least squared means differences analysis (tukey hsd) was performed for all pair-wise tiles (α = . , q = . ). there was no significant difference in mean ratings between any of the vertex equivalent pairs (f b–f c, f d–f e, f b–f c, f a–f f, f a–f b). we conclude that the vertices, although less obvious than some of the larger features in these patterns, affected responding more. this result corroborates the vertex difference findings reported above and shows that our observers are sensitive to vertex properties. unlike in experiment it is difficult to determine a preference for triangles, since all of the patterns contain them. looking at the rankings for polygon type in table there doesn’t seem to be a preference either for patterns with a particular collection of polygons. to illustrate, patterns containing triangles, squares, and hexagons (tsh) are in positions , , , , and , which are at both the top and bottom of the list. however, there are some clusters present in the rankings related to specific types of tile patterns. f g, f c, f d, and f f are all in the top four positions. these tiles all have a global motif consisting of a hexagon surrounded by triangles and squares, indicating that the holistic configuration of polygons is important for aesthetic evaluation. the result implies that participants were perceiving emergent collections of shapes within the tiles and not just processing them at the individual vertex or polygon level. tiles f a and f b were also ranked high, at positions five and six as was f at position eight. these tessellations are characterized by large dodecagons surrounded by interconnecting collections of triangles, squares and hexagons. these patterns can be characterized as having prominent, more circular central spaces. the tessellations at the bottom of the rankings are also informative. f d, f f and f a were the least preferred at positions , , and , respectively. they all have linear stripes of squares that run through them along with stripes of interlocking triangles. the same can be said for f e, f b and f a at positions , and . emergent linear formations thus seem to be less liked than other configurations. the results with regard to symmetry group based on table fall into roughly three categories. first, tiles with symmetry group p m were preferred the most. these tessellations made up the top seven rankings and position . p m tiles have a hexagonal lattice, contain all three symmetry operations (rf, rt, gl) and rotation orders of , , and . as such they appear to have the highest degree of symmetric complexity. second, tessellations in group cmm and pmm were liked the least. these were in the bottom seven positions and at ranking number ten. cmm have rhombic lattices, contain reflections and rotations and a rotation order of . pmm have rectangular lattices, reflections and rotations, with a rotation order of . third, the remaining symmetry groups p m, p g, pgg, and p were in approximately intermediary locations in the list. . conclusions in this study, we examined preference for tessellations containing regular polygons. in experiment we tested the three regular and eight semi-regular (archimedean) tilings characterized by a single vertex, excluding the single enantiomorphic alternate. in experiment we tested the demi-regular symmetry , , of tessellations defined by two vertices. the data from the first experiment show a peak in preference for tiles with two types of polygons and for five polygons around a vertex. triangles were preferred more than other geometric shapes. there was no clear-cut effect of symmetry group and no preference for tiles with a greater number of symmetry operations. the results from experiment show a preference for tessellations with a greater number of different kinds of polygons in the overall pattern and for tiles with the greatest difference in the number of polygons around the two vertices. there was increased preference for tessellations with hexagonal and dodecagonal centers and decreased preference for those with linear square striping. symmetry group p m was liked the most and groups cmm and pmm were liked the least. there are several themes that emerge from the results. the first of these is complexity. this is notoriously difficult to define in a visual stimulus and can vary based on a number of factors [ ]. nevertheless, in our study we will define it based on several features. tessellations with a greater number of polygon types may be considered more complex since they contain a greater variety of different geometric shapes. we see a preference for this in experiment . another form of complexity may be the number of polygons around the defining vertices. this peaked at the second highest number in experiment but showed a linear increasing effect in experiment . we measured this as the difference between the two vertices in the second study. the greater this difference the more heterogeneous the pattern becomes. this was also found to drive responses demonstrating a complexity preference. complexity can also be demonstrated in terms of the symmetry group. pattern p m appears to be the most complex. it has all three types of symmetric transformations, all three rotation orders and reflection in six different directions. p g and p m have the three symmetry types but only two rotation orders. p has all three rotation orders but only one type of symmetry. p m was the number one preferred type in experiment . in contrast, cmm and pmm were least liked in that study and may be considered the least complex. they have two symmetry types but only one rotation order. however, this result must be interpreted with some caution. pgg shares these properties but has no reflections, which may reduce its complexity. it is not clear how to interpret lattice types in terms of complexity but hexagonal lattices were liked the most overall, followed by square lattices. rhombic lattices were liked the least with square and rectangular lattices occupying the middle ground. one of the earliest studies examining fractal patterns varied dimension, recursion, and number of segments in starting generator lines [ ]. ratings of complexity were affected most by recursion and fractal dimension. more recent work has shown that preference for fractal patterns increases with these same measures of stimulus complexity [ ]. this study presented artificially generated fractals to observers who evaluated them aesthetically. preference ratings for most of the participants went up with an increase in fractal dimension. the presence of symmetry interacted with the other variables in their study. preference for patterns at low levels of recursion were increased by the presence of symmetry. most of those tested required a high level of recursion to increase liking for patterns lacking in symmetry. some but not all of the patterns with high rankings in our study had high estimated dimensionality. pattern f d and f b both have lots of space-filling curves, but only the former was rated highly. although our patterns did not have exact repeating structures at different scales, there was approximate repetition for some shapes. for example, f a, f b, f d, f g and f d all have recursive circular formations by individual polygons or collections of polygons at different sizes and were highly ranked but f d, which was also highly rated, does not. a second major theme regards centers. in experiment the preference for vertex centers differing in number of polygons was somewhat surprising because these centers are not always easy to locate, even when one is aware of their presence. our participants were naïve with regard to the mathematical properties of the patterns and average response time was often quick, around one second. the data therefore suggest that observers were able to rapidly process information about the two vertex centers and that these vertex centers had a clear influence on their aesthetic judgments. this finding is corroborated by the vertex equivalent pairs, which were responded to similarly despite cases where their outward appearances were different. it is probable that our participants did not locate these centers symmetry , , of analytically or count the number and type of polygons around them, as they had little knowledge of their existence. instead they were able to perceptually detect the difference somehow by noting changes in the arrangement of polygons across the pattern. based on the experiment results our participants showed a preference for tiles containing hexagonal and dodecagonal centers and did not seem to like as much tiles with linear arrangements of squares or triangles. centers in this sense refer not to vertex centers but to prominent polygons that other polygons organize around. for example, pattern f c has prominent hexagons with triangles and squares around it. it also has salient triangles with other triangles and squares around it. in comparison pattern f f has no perceptually noticeable centers. it appears to consist of alternating linear bands of squares two rows thick interspersed with single linear rows of triangles. to further determine the role of circular and linear arrangements we assigned each of the tessellations in experiment one of three rankings, “c” if it contained a primarily circular configuration of elements, “l” if it had a mostly linear arrangement and “m” if it contained a mixture of circular and linear elements. % of the upper third of rankings were circular, % of the middle third were mixed, and % of the bottom third were linear. this suggests a preference for tessellations with rotational rather than linear configurations. it also strongly demonstrates that emergent structures made of multiple individual polygons are affecting perceived beauty. it may be that recursive spatial scales are more detectable with circular arrangements and that this could be driving preference in these patterns. it is not clear how to reconcile some of the differences between the two experiments. in experiment there appears to be a preference for moderate complexity in terms of preference for number of polygons in the pattern and around the vertex. more complex symmetry groups were not predictive in that study and there was no preference for circular vs. linear arrangements (a linear configurations appears at ranking position and ). in contrast, for experiment there were trends towards increased complexity based on polygons and symmetry, and a distinct circular arrangement preference. one explanation may concern the variety of tilings viewed. if the viewing set is small and the range of pattern examples is limited in terms of complexity and variety, participants may correspondingly limit their preference to lower levels of these measures. when the viewing set is larger and contains a greater variety of different examples, then there may be a shift toward preference for greater complexity. there is much further fruitful ground for study. many different categories of tessellations exist that have yet to be examined from an aesthetics standpoint. these include three-uniform patterns with regular polygons defined by three vertices, mixtures of regular and non-regular polygons, tessellations with star and diamond polygons, monohedral tessellations made from a single shapes like triangles, quadrilaterals, and pentagons, n-morphic monohedral tilings in which the same shape can tile the plane in different ways, homohedral tiles that are similar but not identical, polyiamonds, polyominoes, and polyhexes, escher and penrose tilings, and many more [ – ]. the aesthetics of tessellations and the properties that determine their appeal has hopefully just begun. funding: this research received no external funding. conflicts of interest: the author declares no conflict of interest. references . weil, c.; weil, t. geometric ornament in architecture, art, and design; schiffer publishing: atglen, pa, usa, . . washburn, d.k.; crowe, d.w. symmetries of culture. theory and practice of plane pattern analysis; university of washington press: seattle, wa, usa, . . washburn, d.k.; crowe, d.w. symmetry comes of age: the role of pattern in culture; university of washington press: seattle, wa, usa, . . beyer, j. the secrets of interlocking patterns: designing tessellations; contemporary books: chicago, il, usa, . . seymour, d.; britton, j. introduction to tessellations; dale seymour publications: palo alto, ca, usa, . symmetry , , of . 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. d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : annual review of animal biosciences a beautiful life: high risk–high payoff in genetic science stephen j. o’brien , theodosius dobzhansky center for genome bioinformatics, st. petersburg state university, st. petersburg, russia ; email: lgdchief@gmail.com guy harvey oceanographic center, halmos college of natural sciences and oceanography, nova southeastern university, fort lauderdale, florida , usa annu. rev. anim. biosci. . : – first published as a review in advance on november , the annual review of animal biosciences is online at animal.annualreviews.org https://doi.org/ . /annurev-animal- - copyright © by annual reviews. all rights reserved keywords genomics, conservation, aids, autobiography, evolution abstract this narrative is a personal view of adventures in genetic science and society that have blessed my life and career across five decades. the advances i en- joyed and the lessons i learned derive from educational training, substantial collaboration, and growing up in the genomics age. i parse the stories into six research disciplines my students, fellows, and colleagues have entered and, in some cases, made an important difference. the first is comparative genetics, where evolutionary inference is applied to genome organization, from build- ing gene maps in the s to building whole genome sequences today. the second area tracks the progression of molecular evolutionary advances and applications to resolve the hierarchical relationship among living species in the silence of prehistory. the third endeavor outlines the birth and matura- tion of genetic studies and application to species conservation. the fourth theme discusses how emerging viruses studied in a genomic sense opened our eyes to host–pathogen interaction and interdependence. the fifth re- search emphasis outlines the population genetic–based search and discov- ery of human restriction genes that influence the epidemiological outcome of abrupt outbreaks, notably hiv–aids and several cancers. finally, the last arena explored illustrates how genetic individualization in human and animals has improved forensic evidence in capital crimes. each discipline has intuitive and technological overlaps, and each has benefitted from the contribution of genetic and genomic principles i learned so long ago from drosophila. the journey continues. a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . mailto:lgdchief@gmail.com https://doi.org/ . /annurev-animal- - https://www.annualreviews.org/doi/full/ . /annurev-animal- - av ch _obrien arjats.cls january , : it’s a very ancient saying but a true and honest thought, that if you become a teacher, by your pupils you’ll be taught. —oscar hammerstein ii, the king and i ( ) introduction penning an autobiography is a singular challenge, mostly because the task is hugely subjective. two anecdotes around this exercise help me explain my conundrum. nbc tv journalist and -year host of meet the press tim russert recalled a walk with his dad—folks called him big russ—in buffalo when tim was years old ( ). they passed by a neighborhood church where parishioners were queuing up for a holy service. big russ told his son, “tim, i want us to wait here at the church door for a bit and then, when the service is completed and the worshipers emerge, i have a lesson to tell you.” as the service concluded and the people made their way home, russ said, that was some poor fellow’s funeral. did you notice how long the service was? it took approximately minutes— minutes to honor his memory, to say nice things, and to highlight his lifetime accom- plishments. when you and i pass on in the future, that’s the time we will get, so be sure the worshipers have something important, relevant, or meaningful to say. your whole life in minutes. wow! a second recollection, which raises the prospect that most biographies are apocryphal, is from a classic book written in entitled in search of excellence: lessons from america’s best-run com- panies ( ). the authors offered profiles of a handful of fortune company ceos asking each for the secrets to their success in leading the world’s most influential commercial institutions. the ceos had detailed explanations and insightful reasons for their achievements. but then the authors interviewed deputies and managers of the companies’ executives and got their view of the same question: “what were the most definitive characteristics of the ceo’s suc- cess?” the opinions from these subordinates were equally descriptive and credible, but in nearly all cases very distinct from the reasons the ceos themselves had mentioned. why? because the staff had the perspective of standing back over a decades-long career as observers and offered what they believed really made the difference. the ceos had more cryptic, personal, and recent per- spectives, influenced by their latest actions, challenges, and movements. who was correct? maybe both? can i be so objective myself? i can only try. my own career was stimulating, complex, curious, and fascinating. as a geneticist, i am sup- posing that “nature” awarded to me some good useful aptitudes, but perhaps as important was the “nurture” component: the teachers, colleagues, students, extraordinary support, empirical op- portunities, unanticipated discoveries, peer recognition, science culture, and a bit of good luck. to some, my history sounds simple, even routine: a phd in drosophila genetics; a postdoc at the national cancer institute of the national institutes of health (nci-nih); + years of staying put; then capped off by a genome bioinformatics adventure in st. petersburg, russia. the editors of the annual review of animal biosciences have invited me to expand on my view of how it all came together. because i was anything but focused on my research endeavors, my steps look chaotic and episodic. to help tell this narrative more clearly, i emphasize discrete genetic research disciplines that i became enamored with, for better or for worse, and tell the stories through a genomic lens. origins i was born in to bernard and kathryn o’brien in rochester, new york. kathryn was a college-educated secretary who raised four children (i was number three), and bernard was a o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : self-trained radio engineer. he began by building crystal radio sets in the late s, and with but a high school diploma, he went on to build the cbs radio station and then the tv station in rochester, where he became chief engineer. in my early youth, i paid little attention to sci- ence, being more interested in baseball, dogs, and rock and roll. my family relocated to bethesda, maryland, outside washington, dc, in , where i had a rather undistinguished high school performance that, to be frank, would limit my college admission opportunities. one thing i did enjoy in that period was singing and dancing in amateur high school musicals. looking back, i suspect that these on-stage appearances provided terrific preparation in building confidence for public speaking later in the science arena. after hitchhiking miles each day to good counsel high school in wheaton, maryland, i was excited to enter st. francis college, a small liberal arts catholic school run by franciscan friars in the hills of western pennsylvania. st. francis was good for me. it protected me from my adolescent instincts, prejudices, and lack of career focus. the teachers were patient but demand- ing. i majored in biology and chemistry in a premedical track. my original plan was veterinary medicine, as i loved dogs and animals. but my dad advised me that the veterinary course was both rigorous and demanding, perhaps as much as medicine, so maybe i should consider medicine, because the payoff both culturally and financially could be more rewarding. the premed track i entered was not a perfect fit, and it showed from my transcripts. and then my life took a big turn. a young new professor at st.francis,dr.james edwards,arrived to teach the emerging fields of genetics, evolutionary theory, and microbiology. edwards lectured to small classes with extraor- dinary depth, insight, knowledge, and enthusiasm. his talks were sagas of the great discoveries in the beginnings of genetics and molecular biology. the characters were familiar: george bea- dle, barbara mcclintock, thomas hunt morgan, calvin bridges, watson and crick, marshall nirenberg, jacob and monod—the list goes on. i was hooked. this was not about memorizing endless anatomical details or latin names of countless plants or insects. biology came alive in the details of transcription, translation, development, operons, gene maps, transfer rnas, messenger rnas, and empirical science design. a few students like me embraced it, devoured the excitement, and immersed ourselves into the field. i would remember a lesson from my father, when i asked him why he chose radio engineering as his profession that he did so well in. his response was, “well i was pretty good at it, but also the great advances and discoveries that were driving things forward in radio electronics were all accomplished by young, innovative, and aggressive engineering pioneers. i really wanted to meet them all.” to me at that time, such a field was molecular biology and genetics. my academic performance skyrocketed. edwards embraced and navigated my dream. as a determined mentor, he encouraged me to take summer courses in calculus and differential equations, then to elect a physical chemistry course in my senior year,top out in all of these,and apply to the best universities for graduate train- ing in genetics. i did this and was accepted at half of the high-end schools to which i had applied. i chose a graduate fellowship at cornell to work with bruce wallace, a well-known evolutionary geneticist and himself a student of the population genetics pioneer theodosius dobzhansky. i drove to ithaca the day after my graduation from st. francis in . comparative genomics: genetic maps to whole genome sequence bruce wallace was a creative and kind teacher who penned textbooks in population genetics, de- signed provocative drosophila experiments, and led social science education. more direct oversight www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : and training were provided by ross macintyre, a zealous young molecular geneticist, who as a cornell assistant professor set a high bar for groundbreaking and important molecular genetic research. my first project, an empirical attempt to quantify overall genomic diversity in drosophila populations with allozyme (allelic isozyme) variants, was successful, but my findings came in the wake of a report by dick lewontin and jack hubby (university of chicago), who estimated that something like % of tested allozyme genes had electrophoretic variation ( , ). after a few more population genetic reports ( ), i developed a strong interest in functional genetics for genes of the α-glycerophosphate cycle,a component of energy metabolism in drosophila flight muscle.i learned how to induce knockout mutations that caused weakened flight and early senescence phenotypes in flies ( – ). this work would stimulate a postdoctoral appointment at the national institute on aging in baltimore with bertram sacktor, a pioneer in insect metabolism and energetics. all the while, ross and i were continually mapping new gene markers until we had enough enzyme genes to put together a biochemical map for drosophila ( ). to me, gene mapping was a keystone to functional genetics; we desperately needed a catalog for the genes and mutational alterations that affected all things biological. calvin bridges and alfred sturtevant had initiated drosophila genetic maps years before using observable variant phenotypes (eye color, bristle patterns, and wing morphology). by the late s, it was time to add molecular enzymes and pro- teins to these maps to connect genetics to the fast-moving and exciting new discipline of molecular biology. the nih was a happening place in the early s. the war on cancer had been declared by nixon and embraced by nci. the discoveries of mammalian retroviruses were blossoming— scores of oncogenes were being uncovered by rescues from retroviral isolates from leukemias and sarcomas in chickens, mice, primates, and cats. because i wanted to be part of this excitement, i would shift my postdoc from baltimore to nci in bethesda to join a red-hot program headed by george todaro, a truly brilliant biomedical researcher who among other things had formulated the term oncogene ( ). i was hoping that my genetics and gene mapping background would offer a useful perspective. this hunch led to my developing somatic cell hybrid panels for mapping human genes. frank ruddle (yale) and tom shows (roswell park comprehensive cancer center in buffalo, new york) had streamlined human mapping to an efficient process for mapping the first human molec- ular isozyme genes on human chromosomes. i learned from these two how to construct somatic cell hybrids and to definitively map human genes. later zoofish (chromosome painting) tech- niques augmented the hybrid approach, along with the radiation hybrid (rh) mapping methods developed by david cox (ucsf) and peter goodfellow (cambridge). applying these state-of- the-art mapping technologies, the small group i was building at nci was invited into more than exciting collaborative studies to map the newest oncogenes, retroviral integration sites, tumor suppressor genes, and other gene determinants of cancer. bill nash, bill modi, joan menninger, and i participated in scores of gene assignments for new genes in the armament of cancer research. we had the technology, nci had the money, and the cancer molecular biologists were handing us new gene sequences of interest at a steady pace ( – ). early on in this period, my students and i decided to emphasize a research area that could become our own principal emphasis. i was intrigued by the retroviral advances in cancer research but felt an area that was lacking was uncovering variants in immune response genes, which reg- ulate virus transmission and disease progression. i wanted to choose a nonhuman species with retroviral pathology to begin host genetic analyses. four obvious models were considered: mice, cats, monkeys, and chickens. i excluded mice (too many great researchers there already), monkeys (too expensive and difficult to get numbers), and chickens (too evolutionarily distant from hu- mans to be so relevant). this left domestic cats, which had advancing virology for feline leukemia o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : virus (felv); feline sarcoma virus (fesv); feline herpesvirus; feline coronavirus; and later feline immunodeficiency virus (fiv), first cousin to hiv. we constructed several panels of cat–rodent somatic cell hybrids and began mapping the cat genome ( ). we built a linkage map with a breeding pedigree between house cats and a related species, leopard cats (prionailurus bengalensis), developed at the nih animal breeding facility in poolesville, maryland ( ). this was exciting to me and sparked a career-long fascination (indeed, obsession) with the biology, evolutionary genetics, and medicine of cats ( – ). our choice had one unexpected advantage: the amazingly prescient cancer and oncogene researchers (todaro, huebner, aronson, skolnick, lowy, klausner, sherr, varmus, gallo, vogelstein, and others) be- came my friends and were very willing to help train my students in their latest technologies. with a determined, perhaps misguided, interest in cats, we were not really considered as competitive to these pioneers. our publication and subsequent expansion of the cat gene map made an important point in the emerging field of comparative genomics. cat genes were organized into syntenic groups that were remarkably similar to the order of homologous genes on human chromosomes. cats have chromosome pairs, and humans have pairs. six of the chromosomes bore the same gene clusters in both species, and the other chromosomes had very few interchromosomal exchanges (called translocations). by , zoofish and hybrid maps showed that one could rearrange the human gene syntenic segments into the cat gene order with as few as scissor cuts or exchanges ( – ). the same comparison of syntenic segments required ∼ scissor cuts to rearrange the human map to the mouse map. today, whole genome sequence analyses reveal additional intra- chromosomal inversions and segment transpositions, but the highly conserved ancestral genome organization demonstrated by cat and human genome mapping in the s remains true. i was invigorated by the comparative genetics discoveries in the s and s. we took on the task of comparing homologous gene orders and rearrangements among distantly related mammal species, all the while interpreting them in terms of the evolutionary and genomic deter- minants. this concept blossomed to become the comparative genomics discipline, which details the similarities in gene order and the fixed evolutionary rearrangements that preceded the origins of modern species ( ). to promulgate this area, we needed precise and detailed gene maps of representative species of mammalian orders and families. as the human genome began to take shape, the importance of comparative data became crystal clear. in the s, human gene mapping workshops kept up with the rapidly developing maps of each human chromosome. indeed, the workshops had committees dedicated to human chromosome , to human chromosome , to human chromo- some , to human chromosome …all the way to chromosome . almost as an afterthought, our comparative committee was added to the group. the lead workers on gene mapping for mouse (peter lalley and muriel davisson), cow ( jim womack and harris lewin), horse (ernie bailey), pig (larry shook and alan archibald), kangaroo ( jenny graves), and cat (moi) agreed to build dense gene maps for each species and to compare the gene orders to impute translocation, inversion, and transposition rearrangements that punctuated genome evolution in mammals. the comparative community mapped genes, aligned the gene maps to different species, and included better gene mapping technologies [restriction fragment length polymorphism, polymerase chain reaction (pcr), dna markers of various sorts]. in , a group of us got together in cape hatteras, north carolina, and designed a series of highly conserved pcr primers across the extensive human, mouse, and rat gene sequences, hoping to successfully amplify the gene homologs of cats, dogs, horses, pigs, and other nontraditional mammals. we called the markers comparative animal tagged sequence (or cats) primers ( , ). the original idea,which others would follow,was to provide a common platform for gene mapping www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : in any placental mammal using the same primers tagged to human–mouse gene homologs. it was an audacious step, but as chinese philosopher lao tzu once mused, “a journey of a thousand miles begins with a single step.” the comparative gene mapping committees working in parallel to map homologous genes in a dozen species were our first step. species gene maps were compiled and published annually by cold spring harbor press in what became six editions of genetic maps: locus maps of complex genomes from to ( ). the first edition in was pages; the last was a massive tome of , pages. when the data grew too large for anyone to carry, genetic maps was displaced by genebank, the nih national center for biotechnology information online database that went on to archive published, unabridged dna sequences deposited from all biological species. around that time, whole genome sequences of model organisms were appearing (escherichia coli, saccharomyces, caenorhabditis, drosophila, and others), thanks to first-generation sanger sequencing (developed by perkinelmer–applied biosystems), pyro-sequencing, and others, and subsequently the cheaper, faster, and robust second-generation gene sequencing offered by, e.g., illumina, pacific biosystems, bgi genomics, and oxford nanopore. an initial full human genome sequence appeared in at an estimated cumulative cost of $ . billion, but questions about its meaning, organization, and interpretation were numerous and seemed to need an evolutionary perspective provided by comparative genome sequencing of related species. the nih national human genome research institute staffed a committee (including myself) to select and fund light sanger sequence of diverse species of mammals for a lesser price of $ – million per species ( ). cat and dog were among those selected for sequencing, leading to a major thrust in the area of veterinary medical models of these two companion animals ( , ). as the cost of genome sequencing was rapidly dropping, david haussler (uc santa cruz), oliver ryder (san diego zoo), and i joined forces in to establish the genome k project (g k), a consortium of geneticists, bioinformaticians, and organismal zoologists committed to facilitating whole genome sequence of approximately , species of vertebrates ( – ). we envisioned a truly transformative gift to the coming generation of biological researchers: a public whole genome sequence for each of the , named vertebrate species for which we could actually gather specimens. g k is thriving as i write these words today. in the decade since its inception, its vision, energy, and commitment have spawned other consortia for genome sequence development for insects, plants, marine invertebrates, all vertebrates, fungi, and others ( – ). coordination of all these consortia was attempted last year by the earth biogenome project (ebp) led by harris lewin and colleagues ( ). ebp proposes to coordinate whole genome sequence of all eukaryote species alive today, some million species, at a projected cost of $ . billion. for the comparative genomics community, it is an ambitious but plausible goal. soon, i expect we will really see genome sequence empowerment for countless species of biological interest and enquiry. in , conservation genomics and functional genomics made a major leap forward when the avian consortium of g k, led by erich jarvis, tom gilbert, and guojie zhang, coordinated the simultaneous production of related papers, many in a dedicated issue of science ( , ), that to- gether analyzed the functional and evolutionary inferences derived from annotated whole genome sequences of bird species. these papers dissected the genetic components of bird biology deter- mining feather development, wing aerodynamics, bone density, olfactory reception, visual opsins, tooth loss, plumage coloration, and many other features. today whole genome sequences have been accomplished for more than vertebrate species, and my own group at the theodosius dobzhansky center for genome bioinformatics in st. petersburg has contributed to the anno- tation and analyses of many of these ( , – ). comparative genomics approaches to whole genome sequences are now being used to impute the genome rearrangements that punctuated the mammalian radiations ( ). i saw the genome revolution come of age. o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : evolution and species natural history in my early days, i was strongly influenced by the writing, teachings, and personal counseling of theodosius dobzhansky, founder of the modern synthesis, a period in the s and s during which genetic advances and evolutional perspectives were joined to enrich both previously warring fields. dobzhansky ( ), considered by many the father of empirical population genetics, is well known for his quotation, “nothing in biology makes sense except in the light of evolution.” no longer was evolution about a creationist debate. rather, it became a keystone for biological inference and interpretation of functional genetics and development. in , i named the center i established in st. petersburg the theodosius dobzhansky center for genome bioinformatics in his honor. in the early s, the powerful discipline of molecular evolution was jump-started by the molecular clock hypothesis first formulated by linus pauling and emile zuckerkandl ( ). since then, conceptual advances in molecular evolution have produced amazing insights and windows into the ancient evolutionary secrets of living species. developed analytical algorithms of evo- lutionary theory and automated computer scripts allowed the construction of statistically robust phylogenies of living species. many workers, including those in my own group, rapidly learned and applied four diverse but complementary philosophies to reconstruct the hierarchical history of species divergence and emergence. the methods had names: (a) numerical taxonomy-phenetic or distance-based methods; (b) cladistics or maximum parsimony methods; (c) maximum likeli- hood statistical approaches; and (d) bayesian statistical methods. today, evolutionary relationships of nearly all zoological groups have been solved with these tools and approaches ( ). in the comparative genomics area, we could not ignore the evolutionary lessons and more im- portant opportunities that were arising. during the s, senior editor barbara jasny at science produced an annual genome issue featuring the best genome advances of model organisms and species. intrigued by the depth of specific genome reorganization that the comparative mam- mal community was revealing, she asked me to help organize a science issue on comparative genomics to illustrate genome exchanges that had been documented among approximately mammal species with gene maps and zoofish ( ). my comparative colleagues and i put to- gether a large wall chart that displayed the chromosomes of mammals colored according to their homologous syntenic segments with the human genome ( ). at the top of the poster was a consensus phylogenetic diagram to show the generally accepted phylogenetic or evolutionary hierarchy of the recognized orders of placental mammals, compiled by a consensus of mammal molecular researchers and paleontological systematists. the colorful genome poster, summarizing the comparative inference to date, adorned the lab refrigerator doors of gene researchers across the world. but there was a catch. our assessment of the consensus phylogenetic tree of mammals was a major stretch, made impossible because the morphologists and the molecular people could not agree at all on the hierarchy or the timing. at this stage, the research team that i directed, nci- lgd (nci’s laboratory of genomic diversity), spearheaded by bill murphy, eduardo eizirik, and al roca, reasoned that if we could use cats primers to map genes, maybe we could design specific cats primers to amplify genomic sequences of available species across mammals to re- solve the mammal phylogeny using the molecular clock. of the more than cats primers they designed, ∼ worked in % of the test species. sadly, the rest failed owing to dna drift across more than million years of placental mammal evolution, but still we had enough to produce a first phylogenetic sampling and analysis across placental mammals ( ). the dating of the mam- mal tree divergence nodes was calibrated with time-calibrated ancient mammal species fossil remains that experts believe were precursors, or missing links, for most of the modern species www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : groups. the fossil date–calibrated mammal phylogeny gave a precise timing and hierarchy for the origins and family-level splits that precede the living mammals of today ( ). nearly every really good idea in science occurs to multiple researchers simultaneously. mark springer’s group (uc riverside) had the same thought for mammal evolutionary history, and in our two groups published independent verification of the origins and divergence of mammal species in nature ( , ). then the springer and o’brien teams quickly combined the data sets from each group and published collaborative affirmation of the major divergence node across the -million-year-old radiation of placental mammals ( ). that relationship has been improved and tweaked but stands today as pretty much the same natural history discerned in . molecular phylogenetic scenarios by my students and fellows would follow the mammal tree cats primer strategy with some notable successes. the cat family felidae is composed of living species that range throughout the world, excluding the arctic, the antarctic, and australia. although catlike species occurred as early as mya in the fossil record, it was consistently agreed that modern living cat species all descended from an ancestor, pseudaelurus, that lived in asia ∼ . mya. the molecular phylogenetic analyses of modern felidae, led by warren johnson, using time calibrated by well-dated cat fossil precursors, affirmed the origins of principal groups (we proposed most as genera) ( ). the combined analyses of phylogenetic hierarchy, the present distribution of today’s cat species, the geological record of sea level rise and fall, and the fossil record allowed us to propose not only a history of species divergence but also a plausible hypothesis for historic intercontinental migrations that preceded the present distribution of the felidae species ( ). similar applications of phylogenetic reconstruction and interpretation are now widespread and have been summarized recently in the timetree of life series ( ) and on websites based upon molecular evolutionary phylogeny reconstruction by a generation of molecular evolutionists (http://www.timetree.org). i had first become fascinated with the power of molecular evolution- ary analyses when we embarked on solving the century-old mystery of the phylogenetic position of the giant panda relative to bears and the red panda, which looks a bit like a raccoon ( , ). this was a fascinating study with a colorful history that i summarized in some detail in my semi- popular book, tears of the cheetah ( ). our research groups would also contribute to phylogenies of the bat family chiroptera (led by emma teeling and leading to the bat k genome sequencing project), primates (led by polina perelman and jill pecon-slattery), pangolins (led by shu-jin luo and agostinho antunes), and carnivora (led by robert wayne) ( – ). an important outcome of the phylogenetic and population studies of nontraditional species was the serendipitous discovery of several new species. in hindsight, the group i led would de- scribe novel, previously unrecognized species of orangutan, clouded leopard, african wolf, south american tigrina, and elephant ( – ). each new species was validated by multiple molecular genetic criteria, and nearly all have been accepted by the international conventions for species recognition. i was struck by a news headline when our group (led by al roca) described a second definitive species of african elephant, loxodonta cyclotis, living in the african congo. the headline read, “new species of elephant discovered in africa—you think it would be hard to miss!” my joy continues. genetics of endangered species perhaps one of the more notable areas of my personal science adventure was the realization that genetic analyses of free-ranging wildlife species can reveal secrets of their past and projections for their future ( , ). this first occurred when david wildt and mitch bush (smithsonian institution) invited me into a study of african cheetahs in the early s. cheetahs were well o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . http://www.timetree.org av ch _obrien arjats.cls january , : known as the world’s fastest land animal, a beauty to observe sprinting across the african savannah. unlike other cat species propagated by world zoos, cheetahs were very slow to breed and, when they did, produced congenital abnormalities at a relatively high frequency. bush, a clinician, and wildt, a reproduction specialist, wanted to explore the biological bases for the cheetahs’ poor reproductive performance. wildt found that cheetahs had a high incidence of morphologically malformed spermatozoa (∼ % abnormal compared with < % abnormal in cats, human, and dogs). in a collection trip to a cheetah breeding center in pretoria, south africa, they retrieved blood samples from cheetahs for allozyme diversity quantification. we screened markers and found zero variation in this initial sample, the first evidence of genetic impoverishment for cheetahs ( ). jan martenson, a talented technical assistant who ran the allozyme tests, quipped, “these cheetahs are so boring and monotonous. for a moment, i wondered if wildt and bush really collected different cheetahs?” the results were that hard to believe. every cheetah was genetically identical to all the others. the clincher to the stunning result came when we surgically exchanged postage stamp–sized pieces of skin graft between unrelated cheetahs. the grafts were all accepted as if they were identical twins ( ). subsequently, we added additional measures that all pointed to the conclusion that the cheetah as a species displays – % less overall variation than other cats or mammals in general ( ). the latest affirmation of the cheetah’s genetic impoverishment came from its whole genome sequence ( ). the cheetah would become the poster-child species for the perils of severe population reduction, mating with close relatives, and shriveling genetic diversity, a prelude for extinction ( , ). studies of other species soon revealed that they too had reduced variation because of a near- extinction event in their past. the florida panther, a southeastern us subspecies of cougar or mountain lion, also showed depleted genic variation and consequent congenital pathologies ( % spermatozoa pleiomorphism, cryptorchidism, cardiac defects, and compromised immune system) ( ). the evidence for genetic diminution, combined with clinical details assembled by melody roelke, dvm, led to a florida panther conservation management initiative to augment the > florida panther survivors with healthy wild-caught female texas cougars, a subspecies that had gene flow with the florida subspecies years ago. the restoration program was a dramatic success, resulting in rapid recovery of population numbers, tripling of population size and den- sity, and a measurable increase in fitness for the subspecies intercross offspring ( ). similar ge- netic reduction and restoration proposals have been offered, but never implemented, for asian lions, amur leopards, amur tigers from the russian far east, and california channel island foxes ( – ). genetic diversity is not the only mammal conservation issue genetics has weighed in on ( ). new species discoveries, as outlined above, plus genetic-based categorizations of subspecies also informed wildlife conservation units. for example, the definition of explicit tiger subspecies has confirmed the historically separated units of tiger conservation, as well as the postulated founder effect for today’s tigers caused by the toba volcanic explosion in southeast asia ∼ , years ago ( , ). subspecies verification also happened with leopards, pumas, tigers, and lions ( – ). population genetic and coalescent dating approaches allowed us to pinpoint the timing of historic demographic events like the cheetah and florida panther bottlenecks ( , years ago around the end of the last ice age for cheetahs and a few hundred years ago for the florida panther owing to deliberate decimation) ( , – , ). ecologists have embraced genetic parentage and kinship estimators to resolve field behaviors in lions and other species. for lions, the development of the pride social unit had an evolution- ary explanation that involved conscious mate choices. oxford zoologist william hamilton had coined the term kin selection to describe a component of natural selection impacted by close www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : relatives other than parents ( ). put simply, if evolution is all about transmitting one’s genes suc- cessfully, would there not be an advantage to helping your brothers and sisters transmit theirs? dennis gilbert’s comprehensive genetic assessment of serengeti lion pride organization solved this conundrum where for lions everything sexual is a family event, according to lion ecologist craig packer (university of minnesota) ( , ). whole genome sequences are further pinpointing the genes that mediated historic events of evolutionary adaptation. pavel dobrynin’s phd genomics analysis showed that cheetah sperm problems were linked to five damaging knockout mutations in their akap gene, which plays a major role in human spermatogenesis, azospermia, oligospermia, gonadal dysfunction, and ooge- nesis ( ). another fascinating example involves the well-known artificial selection experiment for tame behavior involving silver foxes, designed in by dmitry belyaev in novosibirsk, siberia. anna kukekova (university of illinois) recently reported a genome analysis indicating that the docile behavior in the foxes was probably a result of mutations in the very large gene sorcs ( ). today few management studies or planning workshops about threatened species convene without consideration of the genetic and genomic history of that species. plagues among us it occurred to me very early in my career that gene interaction and environment were critically important considerations in understanding the demography and survival of every living species. one of the strongest and most influential of environmental components had to be the role of pathogens, notably viruses, bacteria, helminths, and parasites, that afflicted individuals, popula- tions, and species. in nature, the delicate balance between hosts and their pathogens is akin to a deadly arms race, waged fiercely almost daily and multiplied over individuals, within populations, across geography, and among the more than , mammal species that survive on earth today. the struggle is frequently lost, never won, but temporarily circled with the survivors rising once again to compete another day. in the s, there were public voices, encouraged by the success of antibiotics and vaccines against smallpox, measles, mumps, and polio, who predicted a swift shift in biomedical emphasis from infections to chronic diseases ( ). but then came aids, hepatitis b, hepatitis c, papillo- mavirus, hantavirus, ebola, sars, west nile virus, zika, legionnaires’ disease, mad cow disease, etc. modern medicine had far from conquered infections. not even close. transmissible felv and fesv in house cats became my first exposure to the power of the agents to rapidly overcome a healthy population ( ). felv was supposed to afflict only domestic cats,but that conception was shattered when we encountered a deadly felv outbreak in the fragile florida panther population during its recovery ( ). today we believe that pathogen outbreaks often cause the last step in countless populations’ and species’ extinction events. when the hiv–aids epidemic began in the early s,we never anticipated that there would soon emerge a closely related lentivirus in domestic cats. fiv, first cousin of the deadly hiv, mimicked human aids pathogenesis in infected cats, with a devastating prevalence of – % of the hundreds of millions of feral cats worldwide infected with it ( ). our worries that the deadly fiv may have moved into wild cats were confirmed by a huge epidemiological sero-survey of the felidae species that revealed up to species endemic with fiv ( – ). but for some inexplicable reason, the fiv-infected wild cats did not seem to be getting sick. then, in , a devastating contagion abruptly killed % of the fiv-infected lions in the serengeti. at first, we were afraid that the endemic fiv had caused the death of these lions, but we were wrong ( ). some in-depth histological and molecular analyses of lion necropsy materials revealed that the agent in the serengeti lions was a variant of canine distemper virus (cdv), a o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : morbillivirus (think measles) that was previously thought to cause disease in dogs but never in cats ( , ). not this time. the indigenous maasai tribesmen who herd cattle outside the serengeti had pet dogs that were themselves endemic with cdv, a likely source of the lion agent. dogs are prohibited from the serengeti national park, so how did the lions contact them? we now think the connection involved marauding serengeti hyena packs that also developed cdv titers at around the same time. hyenas, who rumble with both maasai dogs and lions, became our best guess as the carriers of the cdv from maasai dogs to serengeti lions. in truth, packer and roelke’s vigilant surveillance of the lions and dogs opened our eyes to a close-up view of a horrific fatal outbreak in a large predatory carnivore ( , ). quickly thereafter, a vaccine initiative targeting the maasai dogs ensued, which seems to have prevented further outbreaks over the coming decades. a lesson of host gene influence during viral outbreaks became crystal clear when the sars (severe acute respiratory syndrome) epidemic emerged in november . the flulike disease defied any and all treatments as it abruptly appeared in the emergency rooms of chinese hospitals around guangdong, guangxi, and hong kong ( , ). sars was new to medicine, to science, and to people. in months, sars traveled to countries, infected , people, and caused deaths (near % mortality). the alarming speed of spread and virulence of transmission were dramatic. consider that a single patient admission at the prince of wales hospital in hong kong transmitted to cases within a few hours. a nearby sprawling hong kong apartment complex, amory gardens, home to , residents, developed sars cases after an infected woman coughed into the ventilation system. the condo became a ghost town within a few days. the sars epidemic was quickly shown to be caused by a novel coronavirus related to that which causes one-third of common colds. although sars subsided in may , likely as a con- sequence of draconian quarantine measures, the deadly epidemic scared us all. sixteen years later, we still have only a vague understanding of the precise mode of transmission, no laboratory-based clinical diagnosis, and no vaccine or efficacious treatment for sars. the abrupt and deadly disease had spread at lighting speed, leaving dire economic consequences in the billions of dollars, along with a dramatic asian cultural shift toward avoiding handshakes, kisses, or any physical contact ( , ). coronavirus pathologies at the time were actually more familiar to veterinary clinicians, who had seen coronavirus diseases in mice, turkeys, chickens, pigs, dogs, and cats ( ). although i had been aware of these, the sars episode set off an alarm as i recalled a devastating coronavirus epidemic we encountered in the s in cheetahs ( ). at the same wildlife park in oregon where we had exchanged skin grafts between unrelated cheetahs, a pair of imported cheetahs from sacramento arrived and grew ill with fevers, jaundice, and acute tremors. with little but symptomatic treatment, the two cheetahs deteriorated and succumbed to an unknown contagion. biopsies and viral screening revealed they were infected with a domestic cat coronavirus called feline infectious peritonitis virus (fipv). in cats, fipv induces an accumulation of proteinaceous immune complexes in the peritoneum that strangulates the organs, leading to death. the fipv quickly spread through fecal transmission across the park, and within a few months all cheetahs had seroconverted ( ). by the time of the sars outbreak (in ), newly available molecular tools allowed us to recover fipv sequence from archival specimens to trace their origins. the cheetah virus was nearly indistinguishable from fipv isolated from domestic cats ( ). why is that important? the cheetahs’ fip morbidity (symptoms) was % (including chronic diarrhea, jaundice, and tremors), and % of the infected cheetahs died of the disease within three years. in domestic cats, fipv morbidity is usually < %, and mortality ∼ %. in human sars, the mortality was < %. a near-uniform response of cheetahs to the fipv was no coincidence. the fipv, once it had www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : overcome the defenses of its first cheetah victim, had overcome them all. cheetahs were all genet- ically the same (remember the skin graft results). the cheetahs’ smoking gun was their endemic genetic uniformity, including the immune defense genes ( ). this homogeneous clinical response to fip in cheetahs convinced me and my colleagues that the genetic context of immune defenses had an enormous influence on the outcome of a novel emerging virus in a naïve population. this lesson i would never forget. aids-restriction genes and the era of genome-wide association studies a clear potential of the comparative inferences unfolding in my early scientific career was the hope to translate animal insights to human medicine. our research group at nci began a remarkable journey in the early s when we looked for a chronic infectious disease that likely had host genetic components contributing to epidemiologic outcomes. we chose hiv–aids as our target because the disease first emerged in , clearly involved an infectious agent (hiv), and was deadly to % of its victims. we were hoping that the natural genetic variants, once unveiled, might lead to better diagnosis, to effective drugs, or even to prophylactic agents. after first consulting with human geneticists and aids experts and securing nci financial sup- port, we mounted a search for what we called aids-restriction genes, host genetic variants that influence epidemiologic heterogeneity among hiv-exposed individuals. we entered into collabo- rations with diligent epidemiologists, who were studying principal aids risk groups (actively gay men, hemophiliacs who received contaminated clotting factor before the advent of hiv screening in , and iv drug users who were sharing contaminated hypodermic needles in urban settings). we sought to connect the clinical data documented by the epidemiology communities with dna variants across the human genome as they were described by human geneticists and the fledgling human genome projects. to do this, we gathered blood samples from the at-risk cohort volunteers. our strategy was to genotype large numbers of individuals in the aids cohort studies with dna variants in candi- date genes (those genes implicated as important in aids pathogenesis) for hiv infection, aids progression, aids-defining diseases (kaposi’s sarcoma, lymphoma, pneumocystis carinii pneumo- nia), other clinical indicators of aids, and differential responses to available therapy (after termed haart for highly active antiretroviral therapy). for detection, patients were parsed into groups with different disease outcomes so we could compare allele frequencies of variants between groups, as well as conformance to hardy–weinberg equilibria and other population genetic equi- libria measures. when a certain gene allele showed higher frequency in one group versus another (e.g., hiv negative versus hiv positive), it was the first signal that the allele conferred resistance to hiv infection. between and , we accumulated more and more patients from some cohorts who agreed to be part of our ambitious study consortium. we recruited nearly , patients, a rich repository for the discipline of genetic epidemiology. at nci-lgd, cheryl winkler and mary eichelberger built a cell transformation laboratory that produced immortal b-cell lines us- ing epstein–barr virus transformation protocol from most of the blood samples. raleigh boaze extracted high molecular weight from each sample. i had hired michael dean, a superb young molecular biologist, to develop the human genotyping technology. mike carried out the dna genotyping for hundreds of gene candidates (mary carrington led the hla and kir typing ef- fort), all in search of a statistically significant population genetic signal for aids influence. for more than a decade, the clinic doctors and nurses, our epidemiologic collaborators, cheryl winkler, mike dean, mary carrington, and i continued to add more patients, more genes, more o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : genetic variants, and more sophisticated computer programs to search for aids-restriction genes. by the mid- s, we had screened thousands of patients for hundreds of gene variants distributed across the human chromosomes. every so often, we spotted a genetic difference between groups, but they all evaporated under closer inspection. we would monitor new research advances that were reported in the aids literature, searching for new genes to test. finally, years after we had begun what was becoming a tedious, expensive, and thus far disappointing fishing expedition, there appeared a glimmer of hope ( – ). in july , four separate studies from independent groups (not us) reported in nature, cell, and science a requirement for the ccr chemokine receptor molecule for hiv to enter lymphoid cells ( – ). hiv binds to two receptors on t-lymphoid cells, ccr and cd , in a stepwise process to enter these cells and destroy them. in an infected victim, hiv then produces more than a billion viral particles each day. cd -bearing t lymphocytes eventually become depleted, leading to collapse of cell-mediated immunity, thereby allowing normally innocuous infections and certain rare cancers to proliferate and kill the victim. we designed pcr primers to amplify the cd and ccr human genes and search for gene variants the day after the announcements appeared. our team quickly discovered a large ( – nucleotide pair long) deletion in the ccr gene (ccr -� ) in some but not all patients. when we genotyped the aids cohorts, an incredible result appeared. although the ccr -+/+ and ccr -+/− genotypes were found in both hiv-positive and hiv-negative patients, the hiv- negative patients were never homozygous for ccr -� /� . it seemed the people with ccr - � /� were completely resistant to hiv infection, no matter how many times they were ex- posed. the reason was that the requisite ccr receptor—the doorway by which hiv enters t lymphocytes—was slammed shut. other groups would opine that ccr -� might confer re- sistance to hiv ( , ), but our result ( ), published in science on september , , proved it with the genotypes of , people from separate aids cohorts. later we would extend and expand these studies around the details, geographic distribution, and origins of ccr -� in scores of derivative reports ( – ). ccr -� remains today one of the more wide-reaching success stories of human gene associ- ation.several anti-aids drugs that block ccr –hiv binding (fuszon-enfuvirtide and maraviroc) were developed and approved as aids treatment by the food and drug administration ( ). we noticed that ccr -� mutation is found mainly in europeans (but virtually absent in pure east asian and african ethnicities), indicating it first occurred in europe after the “out of africa” mi- gration and was likely raised to a % allele frequency by the sixteenth-century black death and earlier bubonic plague episodes. both the berlin patient and london patient, the only two indi- viduals to have had hiv cleared or cured (of the million hiv carriers alive today), received a stem cell transplant using hla-match donors who were homozygous for ccr -� /� ( – ). there are provocative reports that ccr action is important in graft-versus-host disease (gvhd), which can kill up to one-third of bone marrow transplant recipients in cancer therapy ( , ). phase i and ii trials using maraviroc (a ccr antagonist) treatment after bone marrow transplants showed remarkable ablation of gvhd incidence without side effects. ccr -� has been shown to mediate more rapid recovery from stroke ( ). alternatively, homozygous ccr - � /� carriers are at a fivefold-increased risk for developing encephalitis after infection with west nile virus ( ). finally, chinese scientist jiankui he’s ethically challenged crispr-based germline editing claim this year targeted ccr to protect two newborn babies from hiv infection ( , ). the experience and follow-up with ccr invigorated our team to use the aids cohorts to discover some additional aids-restriction genes ( ) (table ). each was published, and most were replicated in independent cohort studies. however, because nearly all showed a www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : table aids-restriction genes described by the nci’s laboratory of genomic diversity ( – )a no. year gene allele mode effect ccr Δ recessive prevents infection ccr Δ dominant delays aids ccr i dominant delays aids ccr p p recessive accelerates aids sdf ’a recessive delays aids ccr Δ dominant prevents lymphoma hla a,b,c,“homozy” codominant accelerates aids il ’a dominant limits infection il ’a dominant accelerates aids hla b∗ px codominant accelerates aids rantes − a dominant accelerates aids in . c codominant accelerates aids kir ds epistatic (bw – ) delays aids eotaxin-mcp hap dominant enhances infection hla b∗ codominant delays aids ifng t dominant accelerates aids cxcr e k dominant accelerates pcp apobec g h r recessive accelerates aids dcsign − t dominant decreases infection hla b codominant delays aids tsg hap dominant accelerates aids trim hap dominant increases infection cul hapi codominant accelerates cd loss pp a (cyclophilina) snp- dominant accelerates aids hla bw dominant reduces hiv transmission myh end-stage renal disease myh hiv fsgn mtdna hap-j, u a dominant accelerates aids mtdna hap-h dominant increases lipatrophy post haart mtdna hap-j dominant delays cmv-nrd hcp t>g; rs dominant hiv set point hla rs dominant hiv set point prox hap-cgt recessive delays aids progression apobec b �v_ recessive increases infection peci g dominant accelerates aids acsm a codominant delays aids ncor t dominant increases infection idh a. c dominant prevents infection pard- b b. c codominant delays aids aall these genes were discovered or validated using the nci’s laboratory of genomic diversity. eight aids cohorts including more than , study participants were used in these studies from to (see for citations). abbreviations: aids, acquired immunodeficiency syndrome; cmv-nrd, cytomegalovirus neuroretinal disorder; fsgn, focal segmental glomerulosclerosis; haart, highly active antiretroviral therapy; hiv, human immunodeficiency virus; nci, national cancer institute. o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : quantitative allelic difference (unlike the gene-knockout effect of ccr -� ), clinical follow-up and translation have been less aggressive than for ccr . finally, we have used similar gene asso- ciation studies, including genome-wide association studies, to discover multiple restriction genes for hiv–aids in africa ( ), for hepatitis b and c in china ( , ), and for nasopharyngeal carcinoma in china ( ). these advances joined in complex gene discovery during the genomics era make me quite proud of the nci-lgd team, who really were among the early formulators of a human “genetic epidemiology” discipline. forays in forensic science my earliest tiptoe into forensic genetics began with the work of walter nelson-rees, a foren- sic pioneer who uncovered cell culture mix-ups or contaminations with hela cells in the s. walter would request samples of well-known cell lines studied by major cancer research groups and then resolve hela karyotypic markers, visible chromosome translocations, and rearrange- ments specific for the rapidly growing hela cells (made famous recently by the book and movie about the unwitting donor, henrietta lacks; ). nelson-rees would catalog and publish all the cases in which he received a cell line with a certain name and origin label that really turned out to be hela cell contaminants ( , ). often his public announcement of cell-line misidentifica- tion ruffled the feathers of the world’s cell biologists, who expected respectful confidentiality. at the time, we were researching human allozymes and their population frequencies. nelson- rees urged me to develop a panel of allozyme markers that would individualize human cell iden- tification and also a cell line’s species origins. we did this quickly, contributing to several releases of cell-line screwups, as well as developing statistical rigor associated with individual genetic uni- formity ( – ). this was a prelude to the better-known dna fingerprinting and product rule calculations used today in courtrooms across the globe. in the fall of , a year after the televised o.j. simpson murder trial taught laymen the power of dna fingerprinting for individual identification in capital crimes, i was contacted by constable roger savoie of the royal canadian mounted police to help solve the murder case of a young mother on prince edward island ( , ). the mounties had uncovered a leather jacket in the woods near the crime scene that was spattered with the victim’s blood, identified by dna fingerprinting. nested in the jacket lining were whorls of white hairs that were not human but feline. the prime suspect lived with his parents and a large white tomcat named snowball. because of our reputation as cat genetic experts, savoie asked me to try to determine whether the jacket hairs were from snowball, which would connect the suspect to the crime scene. marilyn raymond and victor david, crack geneticists on the nci-lgd feline research team, took on the project and performed the dna analyses that in the end allowed for a conviction and sentencing. the jacket hair dna showed a perfect match to snowball. we then had to build an ad hoc population genotype database of stray cats from prince edward island. the island cats had abundant variation and allowed us to compute the likelihood of a chance match of snowball to another local cat to a vanishingly tiny probability of in , , . the suspect was convicted and sentenced, setting an international precedent for animal genetic individualization in capital crime cases. constable savoie, who recruited us and oversaw the case against the suspect, was awarded the high honor of mountie of the year in for his persistence. details of the snowball case are described in more depth in reference and in a derivative tv episode of forensic files ( ). our connecting of dna forensics to species conservation came with the saga of rhinoceros marauding in africa. two species, white and black rhinos, survive today as critically endangered species in southern and eastern africa. both species were objects of intensive conservation www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : protection and relocation efforts in the twentieth century. at the end of the nineteenth century, southern white rhinoceros (ceratotherium simum simum) numbers had declined to between and animals but were restored to more than , , primarily in south africa, in an effort led by dedicated south african conservationist ian player ( ). black rhinoceros populations dove from approximately , in the early twentieth century to , in and increased to , by ( ). both rhinoceros species have seen a hundredfold increase in illegal hunting since . more than , rhinoceros have been killed through poaching across africa, with south africa suffering the highest losses. the slaughter is driven by an appetite for rhino horns, which are considered both of medicinal value and as a cultural status symbol in asian countries, mainly vietnam and china. organized crime circuits with automatic rifles, helicopters, and sophisticated trafficking and smuggling systems earn enormous profits. the risks are relatively modest: a small fine, a few weeks in prison, or a slap-on-the-hand warning. enter cindy harper, dvm, an amazing veterinary geneticist at the university of pretoria. at first, cindy supported her lab and research by assessing the parentage and breeding structure of farm animals and some captive wildlife programs. she embraced the rhino poaching crisis with a personal passion. she optimized a group of short tandem repeat dna markers specific for rhinos to assess species, gender, and individual identification of confiscated specimens. cindy’s team developed an extensive database of rhinoceros dna profiles and demographic information named rhodis® (rhino dna index system), modeled after codis, the us federal bureau of investigation criminal dna database ( , ). the rhodis® forensic system involved training and certification of police and wildlife officials, a chain-of-custody compliant sampling methodology used for live and dead rhinoceros and rhinoceros horns, an erhodistm field data collection app, and state-of-the-art dna genetic individualization. harper has trained more than rangers, police officers, and conservationists. to date, more than , individual rhinoceros specimens and genotypes have been accessioned to the rhodis® database. these data include more than , forensic case samples for which links were made between recovered horns, blood-stained evidence items, and specific rhinoceros carcasses in > cases. in the most recent cases, this forensic genetic individualization allowed heavy punishments upon conviction, establishing international legal precedents for prosecuting and convicting smugglers of rhino horns suitable for trafficking in other endangered species ( ). cindy asked me to serve as her phd supervisor and her counselor. i used our snowball experience to fine-tune the forensic development of chain of custody, plus the population genetic statistics for confirming dna matches based upon accepted dna fingerprinting product rule calculations. we learned an enormous amount of legal detail from the stories of cindy and her team. to date, cindy’s group has submitted hundreds of dna forensic case reports. so far, more than prosecutions of poachers have ensued, with most leading to swift convictions and life-altering sentences of – years of prison. because of cindy’s dedication and determination, dna fingerprint identification has set a new high standard for wildlife forensics and prosecution. her vigilance has changed the world positively and i, for one, am humbled and proud to have played a minor supporting role. communicating science advances publishing research findings in peer-reviewed journals, hopefully of high esteem, is the currency of good science, critical for performance reviews and securing of funding for future research op- portunities. our team of talented students, fellows, and colleagues released more than articles together, including several more wide-ranging review articles (scattered across the citations be- low). i also learned that clear and more general syntheses beyond technical reports are of special o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : value. since my early youth, i had admired the skillful prose and illustrations of scientific american, knowing that these articles would inspire or inform the general science background of important discoveries featured in high school and college textbooks. i dreamed that someday i might write a piece in scientific american that would reach beyond my traditional peer audience to young students of science, teachers, and nonspecialists. looking back, my -year career allowed for five scientific american articles, each on a different topic [cheetahs ( ), giant pandas ( ), ccr -� ( ), felidae natural history ( ) and the cat domestication process ( )]. in , i published a semi-popular book, tears of the cheetah and other tales from the genetic frontier ( ).tears contained science adventure stories stimulated by accounts of our work that had been featured in tv and newsprint media.although these professional outlets made us look amazingly good, tears allowed what i hoped was a more accurate and detailed narrative, because i lived the tales personally. i wrote tears to explain our work to my mother; to my sister carol, a folk singer; and to other interested nonscientists. the -year series of genetic maps, vol. i–vi was undertaken to be a telephone book–like com- pendium of genetic maps of all species ( ). the notion was successful, but it simply got too big, with the genome revolution unfolding, and yielded to scores of important web-based gene and dna databases. in , bill nash, joan menninger, and i decided to collect all the g-banded mammalian karyotype figures that were published (or not) and present them in a single atlas of mammalian chromosomes ( ). in , a dramatically updated version of the atlas, edited by alexander graphodatsky, polina perelman, and myself, will appear with karyotypes of , species plus chromosome painting illustrations of comparative studies of evolutionary genome or- ganization ( ). lastly, my wife, diane, reminds me that my -year tenure as editor of journal of heredity ( – ; published by the american genetic association, of which diane was man- aging editor) clearly opened multiple doors and contacts that led to many new collaborations and dear friends. conclusions so i doubt this treatise can be abridged in the minutes big russ had allotted for his son.and i am certain that there are countless alternative views to be offered someday by dear friends, colleagues, and chroniclers. but this is my story told in my words. i do apologize to so many colleagues who have important roles but are unmentioned here. to me the ride was exhilarating, satisfying, and remarkably satisfactory. although i might have preferred major league baseball or rock music if i were blessed with the required talent (i was not), my adventures and experience in science have more than exceeded my expectations. it is not just the rush of an important flashpoint discovery but the satisfaction of hearing of personal discoveries without any appropriation (not so necessary anyway), and the smile of seeing my own scientific philosophy and even temperament displayed when a former student delivers a science lecture advance. as i traveled across the globe, tracking lions, pandas, whales, and sick people, i worked with impressive, dedicated people and tried to help them out through science. my closing parable relates to why i enjoy the extraordinary science experts i encounter so frequently. folk singer harry chapin once interviewed a hero of his, country singer pete seeger. harry asked pete how he felt after all these years being involved in social activism. seeger paused, leaned back in his chair, and drawled slowly, “harry, my involvement in these causes, benefits, marches, demonstrations—i’m not sure they made a difference…” pete was being modest, because for years he had stood up for every major issue of his time, embracing human rights and fighting fascism, nazis, and racism starting in the late s and s. he continued, www.annualreviews.org • a beautiful life a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av ch _obrien arjats.cls january , : but i can tell you one thing. involvement with these issues means you are involved with the good people, people with live hearts, live eyes and live heads… just think about it in terms of your lives. who are the people who are your best friends? who are the people you keep coming back to? who are the people that make your life worthwhile?…usually they are the people who are committed to something. so in the final analysis commitment, in and of itself—irrespective of whether you win or not, is something that truly makes your life worthwhile. so many times across my life i have embraced this precise emotion in pursuit of important science queries. i have been graced to work and interact with the precise people “with live hearts, live eyes and live heads.” certainly scientists discuss, argue, clash, and compromise with their colleagues. we may not always agree or succeed, but we certainly have tried to hit the highest possible standard. my dad urged me to meet all the innovators in my field, as pete seeger wanted to befriend the prescient pathfinders. i have been privileged to do both, one day at a time across so many years. to me, that may be the essence of a wonderful life and an exciting science career. disclosure statement the author is not aware of any affiliations, memberships, funding, or financial holdings that might be perceived as affecting the objectivity of this review. acknowledgments looking back, it seems clear that my career meanderings were blessed with special opportunities, gifted students, fellows, colleagues, and benevolent supporters. i cannot mention them all, but i am grateful to each. nearly all discoveries derive from countless interactions with my terrific grad- uate students (n ∼ ), postdoctoral fellows (> ), dedicated lab and office staff, prescient collab- orators, dear colleagues, and friends (http://dobzhanskycenter.spbu.ru/images/pdf/sjo-cv- june- - .pdf). i employ the royal “we” in several spots to emphasize that the triumphs i enjoyed are theirs, with myself as a cheerful grateful add-on. the employment support and com- fort i received from the us national cancer institute–national institutes of health (nih) ( – ); the theodosius dobzhansky center in st. petersburg, russia ( – ); and nova southeastern university, fort lauderdale, florida ( – ), were the bedrock of my work across the years. for my initial inspiration, my teachers james edwards, ross macintyre, bruce wallace, and theodosius dobzhansky deserve special mention. support from largely government moneys was paramount in my success. i enjoyed an nih training grant for my graduate education at cornell. the nci-nih provided a hefty budget as several wonderful scientist-administrators believed in me and steered resources to my discretion. dick adamson, richard klaussner, george vandewoude, tony fauci, george todaro, and robert gallo deserve special thanks. i could not have done this well without their encouragement and cheerful support. so important in my rem- iniscence are the joys, laughter, support, and love i received from my family—diane, the steady, cheerful, happy lifetime partner, and kirsten and meghan, my daughters, who taught me humility and caution and to set all my goals and standards so very, very high. literature cited . russert t. . wisdom of our fathers: lessons and letters from daughters and sons. new york: random house . peters tj, waterman rh jr. . in search of excellence: lessons from america’s best-run companies. new york: harper & row. presumed st ed. o’brien a nn u. r ev . a ni m . b io sc i. . : - 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( ): – . o’brien sj, menninger jc, nash wg. . atlas of mammalian chromosomes. new york: john wiley & sons . o’brien sj, graphodatsky a, perelman p. .atlas of mammalian chromosomes. new york: john wiley & sons. in press. nd ed. o’brien a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . https://www.youtube.com/watch?v=e ip hoig k av _toc ari january : annual review of animal biosciences volume , contents a beautiful life: high risk–high payoff in genetic science stephen j. o’brien � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � evolution of marsupial genomes janine e. deakin and rachel j. o’neill � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � the genetics and epigenetics of sex change in fish oscar ortega-recalde, alexander goikoetxea, timothy a. hore, erica v. todd, and neil j. gemmell � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � cephalopod biology: at the intersection between genomic and organismal novelties caroline b. albertin and oleg simakov � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � omics technologies for profiling toxin diversity and evolution in snake venom: impacts on the discovery of therapeutic and diagnostic agents cassandra m. modahl, rajeev kungur brahma, cho yeow koh, narumi shioi, and r. manjunatha kini � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � conservation and management of salmon in the age of genomics robin s. waples, kerry a. naish, and craig r. primmer � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � the immunoglobulins: new insights, implications, and applications yi sun, tian huang, lennart hammarström, and yaofeng zhao � � � � � � � � � � � � � � � � � � � � � � importance of the major histocompatibility complex (swine leukocyte antigen) in swine health and biomedical research sabine e. hammer, chak-sum ho, asako ando, claire rogel-gaillard, mathieu charles, matthew tector, a. joseph tector, and joan k. lunney � � � � � � � � � � the role of the gut microbiome in cattle production and health: driver or passenger? eóin o’hara, andré l.a. neves, yang song, and le luo guan � � � � � � � � � � � � � � � � � � � � � � � � african swine fever epidemiology and control linda k. dixon, karl stahl, ferran jori, laurence vial, and dirk u. pfeiffer � � � � � � � � a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . av _toc ari january : influenza a virus subpopulations and their implication in pathogenesis and vaccine development amir ghorbani, john m. ngunjiri, and chang-won lee � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � defining pollinator health: a holistic approach based on ecological, genetic, and physiological factors margarita m. lópez-uribe, vincent a. ricigliano, and michael simone-finstrom � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � the gut–liver axis in the control of energy metabolism and food intake in animals robert ringseis, denise k. gessner, and klaus eder � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � translational advances in pediatric nutrition and gastroenterology: new insights from pig models douglas burrin, per torp sangild, barbara stoll, thomas thymann, randal buddington, juan marini, oluyinka olutoye, and robert j. shulman � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � use of mechanistic nutrition models to identify sustainable food animal production mark d. hanigan and veridiana l. daley � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � regulation of cell fate decisions in early mammalian embryos ramiro alberio � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � implications of assisted reproductive technologies for pregnancy outcomes in mammals peter j. hansen � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � errata an online log of corrections to annual review of animal biosciences articles may be found at http://www.annualreviews.org/errata/animal a nn u. r ev . a ni m . b io sc i. . : - . d ow nl oa de d fr om w w w .a nn ua lr ev ie w s. or g a cc es s pr ov id ed b y c ar ne gi e m el lo n u ni ve rs it y on / / . f or p er so na l us e on ly . [pdf] idealized female beauty, social comparisons, and awareness intervention material: evidence for preventive effects in young women | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . / - /a corpus id: idealized female beauty, social comparisons, and awareness intervention material: evidence for preventive effects in young women @article{arendt idealizedfb, title={idealized female beauty, social comparisons, and awareness intervention material: evidence for preventive effects in young women}, author={f. arendt and christina peter and j. beck}, journal={journal of media psychology: theories, methods, and applications}, year={ }, volume={ }, pages={ – } } f. arendt, christina peter, j. beck published psychology, computer science journal of media psychology: theories, methods, and applications previous research indicates that exposure to the idealized thin media standard of female beauty can contribute to body dissatisfaction, negative self-perception, depressed mood, and disordered eating. importantly, studies have revealed that social comparison processes underlie this negative media effect: women routinely compare themselves with the encountered mass-mediated thin ideals, which, in turn, elicits negative consequences. while there are a multitude of studies on this topic, little is… expand view on wolters kluwer epub.ub.uni-muenchen.de save to library create alert cite launch research feed share this paper citationsbackground citations view all figures, tables, and topics from this paper table figure digraphs and trigraphs social network new media television image fo (complexity) digital media relevance onset (audio) rule operational amplifier risk assessment numerical aperture command & conquer:yuri's revenge unified model bittorrent mass effect trilogy word lists by frequency citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency impact of viewing body image health promotion videos in adult men and women: comparison of narrative and informational approaches. s. mclean psychology, medicine body image save alert research feed a thematic analysis exploring body image and the use of social media amongst young women haiqa ahmed psychology pdf save alert research feed a biopsychosocial model for understanding media internalization and appearance dissatisfaction among preadolescent boys and girls ann rousseau, r. rodgers, s. eggermont psychology view excerpt, cites background save alert research feed original article in behavioral psychology: relationship between social media use and disordered eating behavior among female university students in qatar yara qutteina, c. nasrallah, linda g. kimmel, s. khaled psychology pdf save alert research feed body-, eating-, and exercise-related comparisons during eating disorder recovery and validation of the beecom-r jessica f. saunders, a. eaton, e. fitzsimmons-craft psychology pdf save alert research feed media multitasking, mind-wandering, and distractibility: a large-scale study wisnu wiradhany, m. v. van vugt, m. nieuwenstein psychology, medicine attention, perception & psychophysics pdf save alert research feed intersectional identities and microaggressions: the experience of transgender females c. gerwe psychology save alert research feed körperbilder in der kommunikationsforschung d. hoffmann save alert research feed die rolle der medien bei entstehung, verlauf und bewältigung von essstörungen christina peter, h. brosius political science bundesgesundheitsblatt - gesundheitsforschung - gesundheitsschutz pdf view excerpt, cites background save alert research feed instagram inspiration: how upward comparison on social network sites can contribute to well-being a. meier, alicia gilbert, sophie börner, daniel possler psychology save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency body dissatisfaction: can a short media literacy message reduce negative media exposure effects amongst adolescent girls? e. halliwell, alice easun, d. harcourt psychology, medicine british journal of health psychology highly influential pdf view excerpts, references methods, results and background save alert research feed reducing the impact of media images on women at risk for body image disturbance: three targeted interventions. h. d. posavac, s. s. posavac, r. g. weigel psychology view excerpts, references methods, background and results save alert research feed the role of the media in body image concerns among women: a meta-analysis of experimental and correlational studies. shelly grabe, l. m. ward, j. hyde psychology, medicine psychological bulletin , pdf save alert research feed “the female may feel male:” defending against the adverse consequences of exposure to idealized media images m. häfner, odile jagsch, a. kund, s. mager, philippe türk pereira, anja zimmermann psychology view excerpt, references results save alert research feed the effect of experimental presentation of thin media images on body satisfaction: a meta-analytic review. l. m. groesz, m. levine, s. murnen psychology, medicine the international journal of eating disorders , save alert research feed counteracting media's thin-body ideal for adolescent girls: informing is more effective than warning j. veldhuis, e. konijn, j. seidell psychology highly influential view excerpts, references background save alert research feed intervention of eating disorder symptomatology using educational communication messages sung-yeon park, jacqueline hitchon mcsweeney, gi woong yun computer science, psychology commun. res. view excerpts, references methods save alert research feed virtually perfect: image retouching and adolescent body image k. harrison, veronica hefner psychology view excerpt, references background save alert research feed the effects of the media on body image: a meta-analysis amanda j. holmstrom psychology view excerpt, references background save alert research feed the status of media effects on body image research: commentary on articles in the themed issue on body image and media m. tiggemann psychology view excerpts, references background save alert research feed ... ... related papers abstract figures, tables, and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue axq .. confirmation in a branching world: the everett interpretation and sleeping beauty d. j. bradley abstract sometimes we learn what the world is like, and sometimes we learn where in the world we are. are there any interesting differences between the two kinds of cases? the main aim of this article is to argue that learning where we are in the world brings into view the same kind of observation selection effects that operate when sampling from a population. i will first explain what observation selection effects are (section ) and how they are relevant to learning where we are in the world (section ). i will show how measurements in the many worlds interpretation of quan- tum mechanics can be understood as learning where you are in the world via some observation selection effect (section ). i will apply a similar argument to the sleeping beauty problem (section ) and explain what i take the significance of the analogy to be (section ). finally, i will defend the restricted principle of indifference on which some of my arguments depend (section ). selection effects . biased procedure . random procedure centred propositions and selection effects many worlds sleeping beauty significance of the analogy the restricted principle of indifference brit. j. phil. sci. ( ), – � the author . published by oxford university press on behalf of british society for the philosophy of science. all rights reserved. for permissions, please email: journals.permissions@oxfordjournals.orgdoi: . /bjps/axq selection effects whenever a sample is drawn from a population, some particular method must be used. this method is the selection procedure. the effect this has on the inference is the (observation ) selection effect. eddington’s ([ ]) classic example involves fishing with a net. if we catch a sample of fish from a lake, and all the fish in the sample are bigger than six inches, this appears to confirm the hypothesis that all the fish in the lake are bigger than six inches. but if we then find out that the net used cannot catch anything smaller than six inches due to the size of its holes, the hypothesis is no longer confirmed. so the inference depends on the method of obtaining the sample, i.e. on the selection procedure. there are countless types of selection procedure, but there are only two that we will need. a random procedure is one where each member of the population has an equal chance of being selected for the sample. a biased procedure is one where, if any member of the population has a certain property p then it is selected for the sample. we will say that the procedure is biased towards p in such a case. i will be repeatedly referring back to this definition, so it is worth putting more succintly. if a procedure is biased towards p then: if p is instantiated then p is observed. to get a grip on these selection procedures, let’s consider a simple thought-experiment that has the same structure as the cases we will look at. suppose you are faced with an urn containing either one ball or two, depending on the result of a fair coin toss (two if tails, one if heads). if tails lands, one big ball and one small ball will be placed in the urn. if heads lands, another fair coin will be flipped to determine if the single ball will be big or small. (for future reference, heads and tails correspond to uncentred possible worlds. balls and correspond to centres within those worlds.) i will henceforth leave ‘observation’ implicit. selection effects play an important role in horwich’s ([ ]) analysis of the ravens paradox and jackson’s analysis of the grue problem (jackson [ ]; jackson and pargetter [ ]; godfrey-smith [ ]). its most famous application is the monty hall problem (vos savant [ ]). see (hutchison [ ]; bostrom [ ]) for systematic discussions. i use selection effects in (bradley [ ], [ ]). see also (freund [ ]; shafer [ ]; bovens and ferreira [ ]; and kotzen [unpublished]). these types are not exhaustive. i have used a precisification of the ordinary language term ‘bias’ that is simple and fits sleeping beauty and many worlds. it could be more precisely expressed as ‘maximal bias’. eddington’s example fits a slightly different kind of bias: only objects with p are selected for the sample. i used this definition in (bradley [ ]). groisman ([ ]) also uses an urn analogy to model sleeping beauty, but for a very different purpose. d. j. bradley ball ball heads big or small tails big small a sample of one is taken from the urn. it turns out to be small. how should we describe the evidence? one thing that has been learnt is ‘there was at least one small ball in the urn’. to express this is in a similar way to the problem cases that follow, we can say ‘there is a ball which is small’. e¼there is a ball which is small. but this may not be the total evidence. we may also know the procedure by which we came to learn that there is a small ball. we’ll assume throughout that the agent has full and certain knowledge of the procedure. let’s run through the effects of a biased and random procedure. (we’ll see that whereas in eddington’s fishing case the hypothesis in question would be confirmed if the procedure were random, in this urn case the hypothesis in question would be confirmed if the procedure were biased. this is not hugely signifi- cant, but i mention it to avoid confusion.) . biased procedure first assume the procedure is biased towards smallness. eb¼i learnt that there is a small ball by a procedure biased towards smallness. we could make this vivid by imagining that a small hole is opened and the urn shaken until a ball comes out. big balls won’t fit, so a small ball will be observed whenever a small ball exists. recall that the probability that a small ball exists given heads is / and the probability that a small ball exists given tails is . so the probability that a small ball is selected given heads is / and the probability that a small ball is selected given tails is ; p(eb|h)¼ / and p(eb|t)¼ . assuming the standard definition of con- firmation—e confirms h iff p(e|h) > p(e|-h)—(hacking [ ]) it follows that eb confirms tails. it will be important in what follows that tails isn’t automatically confirmed whenever the procedure is biased. tails is confirmed when a procedure that is biased towards p selects an object with p. if instead a procedure that is biased towards p doesn’t select p, then tails is disconfirmed. for example, if a pro- cedure that is biased towards small balls fails to select a small ball, then there this procedure is such that an object is selected for the sample if and only if it is small. this is a stronger bias than occurs in sleeping beauty and many worlds, as it is incompatible with observing a large ball. everett interpretation and sleeping beauty must be no small balls in the urn. there must be just one ball in the urn (which is large), so heads must have landed. . random procedure now suppose a large hole is opened and the urn thoroughly shaken until a ball comes out, so that every ball has an equal chance of being selected. er¼i learnt that there is a small ball by a random procedure if tails, there is one small ball and one large ball in the urn, so p(er|t)¼ / . if heads, there is a % chance of the urn containing a large ball and a % of the urn containing a small ball, so p(er|h)¼ / . p(er|t)¼p(er|h) so neither heads nor tails is confirmed. when the procedure was biased towards small balls, p(eb|t) was , as a small ball was certain to be in the urn (due to tails), and that small ball was certain to be selected (due to the bias). but now that a ball is selected at random, a small ball is no more likely to be observed than a big ball. so p(er|t)¼ / . in both cases, the agent has learnt that there was a small ball in the urn. but the procedure by which this has come to be learnt affects the inferences we can draw. we can take the procedure into account by conditionalizing on ‘i learnt e by procedure p’, as opposed to just ‘e’. the distinction is between a prop- osition being true and being learnt. bayesians generally assume that e is learnt whenever it is true. this inference from ‘e is true’ to ‘e is learnt’ is equivalent to assuming the procedure is biased towards e, whatever e turns out to be. we will see that in the many worlds interpretation and sleeping beauty case, it is natural to assume the procedure is biased in this way. but once the procedure is brought to attention, it is clear that we should not make this assumption. explaining this point is the main aim of this article. it follows that a problem of confirmation in many worlds is solved (greaves [ ], [ ]) and an argument for the thirder position in sleeping beauty (titelbaum [ ]; papineau and durà-vilà [ b]) is shown to be problematic. before moving on to this, i want to briefly explain the connection between selection effects and centred propositions. centred propositions and selection effects (this section can be skipped without loss of continuity.) frege’s attempt to model our beliefs using uncentred propositions famously floundered on to take two prominent examples, hacking ([ ], p. ) treats the inference from the truth of p to learning p as a ‘trifling idealization’ and howson and urbach ([ ], p. ) make use of an ‘omniscient oracle’. d. j. bradley indexicals. a man lost in a library isn’t helped by knowing merely the uncentred proposition that ‘agent a is at the south end of corridor f, level , at time t’ because agent a could be someone else. the man needs to know that he is at that position now before he knows where he should go (perry [ ]). lewis ([ ]) gives the example of two gods who know every uncentred proposition concerning their world, but each is still uncertain which of the two gods he is. there is no way to describe what they are uncertain about using only uncentred propositions. we also need centred propositions. a centred proposition tells the agent when or where she is located. sentences containing indexicals, such as ‘i’m in london’ or ‘it is now midnight’, express paradigm examples of centred propositions. furthermore, sentences which don’t contain indexicals, but which need to be relativized to a time or place in order to determine a truth-value, such as ‘obama is president’, express centred propositions. lewis (ibid.) asked what happens when centred propositions are added to the bayesian framework and answered ‘not much’. but this answer raises two issues. the first is that beliefs represented by centred propositions change in ways that beliefs represented by uncentred propositions don’t. this is because centred propositions can change in truth-value, so rational belief can change in virtue of tracking that truth-value. for example, the belief that today is monday disappears as midnight strikes and is replaced by the belief that today is tuesday. it is uncontroversial that the bayesian framework—conditionali- zation in particular—must be modified to incorporate this kind of belief change. various theories have been proposed (meacham [ ]; titelbaum [ ]; schwarz [unpublished]) but i won’t say anything about this kind of belief change here (my suggestion is in bradley [forthcoming]). the second issue arises in cases where the agent is initially uncertain about some self-locating fact, and then discovers it. this happens every time you look at a map to discover where you are, or look at a clock to learn the time. note that this is a different kind of case to that of the previous paragraph, for in this case the change in belief is not due to a change in the truth value of the object of belief. (the authors mentioned in the previous paragraph deal with these two issues together, but i think it best to separate them.) i will try to demonstrate that this second way of acquiring a self-locating belief does not present a problem for conditionalization. instead, the complications in such cases are caused by selection effects. selection effects are especially important to such cases because learning centred propositions has a degree of freedom which is analogous to the degree of freedom we have in selecting a sample. this is also the kind of learning that occurs when you learn who you are in the doomsday argument (leslie [ ]). everett interpretation and sleeping beauty for example, suppose you are uncertain which of two regions of space you are in. it might be that you are equally likely to be in either, in which case each has a % probability of being observed by you. we can model this as a case in which there is a random selection procedure regarding which region of space you observe. but now suppose instead that one of the regions of space is life- permitting and the other is not. we can model this case as one in which the selection procedure is biased towards observing the life-permitting region of space. so we can see that when a centred proposition is learnt, we have to ask: is there a reason i am in one location rather than another? that is, what is the selection procedure by which i have observed one location rather than another? i am not saying that selection effects only exist, or are only relevant, when a centred proposition is learnt. quite the opposite—selection effects always exist, and are always relevant, for any piece of evidence, be it centred or uncentred. the connection between selection effects and centred evidence that is most important for our purposes is that learning uncentred evidence is naturally modelled using a procedure whereby if p is instantiated then p is observed i.e. by a biased procedure. and this is not true of learning centred evidence. for example, suppose that bob is the only object in the population. then any selection procedure that selects an object will select bob. so any properties bob has will be observed, and we can model this using a procedure that is biased towards whatever is observed. (if p is instantiated, p is observed.) we often learn uncentred propositions in an analogous way. if i am about to look at a die to see what number it landed on, then i will see the number it landed on. so we can model learning uncentred propositions using a procedure that is biased towards whatever property is observed (e.g. if a six is instantiated then a six is observed). however, if there have been numerous dice rolls, and i won’t observe all of them, then there may be a six in the population that i don’t observe. so the procedure cannot be modelled as biased towards what- ever is observed. similarly, when evidence is centred, we cannot automatically model the procedure as biased towards whatever is observed some of which i will observe and some of which i won’t, and i am more likely to observe some numbers than others. i will now argue that in both the many worlds case and sleeping beauty we must resist the temptation to treat the procedure as biased towards whatever is observed. i will argue that we should model both cases as learning a centred for example, you might learn that a particular raven, bob, is black by being told by someone whose procedure is to tell you that bob is black if and only if not all ravens are black. you have learnt uncentred evidence, yet the selection effect plays an important role in the inferences that can be drawn. d. j. bradley proposition via a random procedure and in both cases neither of the competing hypotheses is confirmed. many worlds suppose we are comparing two mutually exclusive and exhaustive interpret- ations of quantum mechanics. the stochastic theory (st) says that the world is chancy—for a particle in a superposition of up and down that is about to be measured, st says there is a certain chance of ‘up’, and a certain chance of ‘down’. suppose that chance is %. the many worlds interpretation (mwi) says that the world is branchy—the world will split into ‘up’ and ‘down’ branches when the measurement is made. suppose the branches have a weight of %. note that st and mwi are two possible worlds and the branches are centres within those worlds. in st, there is only one branch; in mwi, there are two. branch branch st up or down mwi up down (note the similarity to the urn example.) suppose an agent makes an obser- vation of up. let’s first express that evidence as an uncentred proposition, without making reference to the selection effect, to see how this leads to trouble. e¼there is a branch in which up occurs. (an obvious problem appears to be that e, by referring to a branch, presup- poses that mwi is true. but if st is true, there is only one branch, and e is referring to that one.) does e confirm mwi? this amounts to: is p(e|mwi) > p(e|st)? yes. mwi says that both up and down will occur, so p(e|mwi)¼ , while p(e|st) is / . it looks like our evidence confirms mwi. and notice that it didn’t matter that up was observed rather than down. both outcomes had a probability of given mwi, both outcomes had a probability of / given st, so both must confirm mwi. we get the result that any possible evidence confirms mwi. this result is absurd. but it is not surprising; as mwi says that every out- come occurs, any outcome that isn’t entailed by st will confirm mwi. so it this does not imply that evidence learnt by a random method can never confirm any hypothesis. classical statistics is built on random sampling, e.g. eddington’s fishing case above. ‘weight’ is a rather mysterious entity that is required by mwi to fit the born probabilities, and can be thought of as a measure of existence. unequal weights bring in new complications which i will not go into in detail in this article. see footnote . everett interpretation and sleeping beauty appears that every observation confirms mwi. this line of reasoning is at the root of what greaves ([ ]) calls naı̈ve conditionalization. she rejects (cor- rectly) naı̈ve conditionalization due to its absurd consequences, but she doesn’t say what went wrong with the reasoning, and not everyone is con- vinced that it is wrong. price ([unpublished]) suggests instead that either mwi is wrong, or that conditionalization can’t be combined with mwi. the ap- parent incompatibility of mwi and conditionalization has been considered a fundamental problem with mwi. until we have a diagnosis of what has gone wrong with naı̈ve conditionalization, the suspicion will remain that attempts to give an alternative theory of confirmation in mwi are ad hoc. i will argue that all that has gone wrong is that incorrect conditional probabilities have been used. naı̈ve conditionalization fails to use centred propositions and the observation selection effects that come with them. according to mwi, the evidence learnt when up is observed is not the uncentred proposition that there is a branch in which up occurs, but the centred proposition that up occurs in this branch. the agent has learnt where he is—the up branch. so the first thing we have to do to correct naı̈ve conditionalization is express the evidence learnt as a proposition that is centred given mwi: ec¼up occurs in this branch notice that ec only expresses its intended meaning if expressed after branch- ing. the situation being modelled is that of an agent after branching but before learning which branch he is in. the question at hand is to determine the likelihoods p(ec|mwi) and p(ec|st) for such an agent. the second thing we have to do to correct naı̈ve conditionalization is put in the correct selection effect. the selection effect is trivial given st — you simply observe whatever happens in the one ‘branch’ that exists. if the particle collapses to up, up will be observed. if the particle collapses to down, down will be observed. we are assuming each has a % chance, so p(ec|st)¼ / . however, in order to determine the likelihood p(ec|mwi), we have to ask: given that both outcomes occur, what should your subjective probability be that you—the in-branch agent you happen to be —are in a branch in which up is my position incompatible with greaves’ quasi-conditionalization, or does it render it otiose? neither. i am only concerned with the belief change between (t ) after the branching but when one is still uncertain which branch one is on, and (t ) after learning which branch one is on. greaves is concerned with how we should update from (t ) before the branching has occurred. this is more difficult because before branching one cannot be uncertain which branch one is one, so there is no appropriate conditional probability to be used in conditionalization. (i assume the agent knows whether or not branching has occurred.) wallace ([ ]) worries that the time between branching and the agent learning which branch they are in may be too short for them to be uncertain. but this appears to be just an instance of the problem of old evidence (glymour [ ]). one might object that the only way to individuate ‘you’ is as ‘the inhabitant of the up branch’, and argue that this has a chance of . but the probabilities are subjective, not objective. even if d. j. bradley occurs? the answer to this question will depend on whether there is any bias in the selection procedure. suppose first that the procedure is biased towards up branches. recall this means that if there is an up branch, then it is observed. we could make this vivid by imagining that, given mwi, only up branches are life-permitting. this ensures that if both up and down branches exist, you observe the up branch. so if there is an up branch, you observe it. (if st is true and the spin collapses to up, you observe up; if st is true and the spin collapses to down, there is no up branch and you observe down.) the evidence is now: ebc ¼i learn that up occurs in this branch by a procedure biased towards up branches. as the procedure is biased towards up branches, p(ebc |mwi)¼ . recall that p(ec|st)¼ / for any procedure, so p(e b c |mwi) > p(e b c |st). thus, the evidence would confirm mwi, just as with naı̈ve conditionalization. so it looks like naı̈ve conditionalization is similar to a maximally biased procedure. but there is an important difference. in our analysis, mwi is confirmed by the procedure that is biased towards up successfully selecting an up branch. if instead it selects a down branch, then mwi is eliminated (st and down would be the only possibility left). there is no automatic confirmation of mwi. but naı̈ve conditionalization says there is automatic confirmation of mwi, whatever the evidence. it says that an observation of up confirms mwi and an observation of down confirms mwi. this requires that the procedure is biased towards up if up is observed, and biased towards down if down is observed. so naı̈ve conditionalization must be rejected; even if it is defensible to argue that there is a bias in one direction, there cannot be a bias in both directions for an in-branch observer. the in-branch observer can only observe the branch she is on, so properties in the other branch will not be observed by her. suppose instead that there is no bias. that is, we have a random proced- ure—up branches have the same probability of being observed as down branches, so you are just as likely to be in an up branch as a down branch. so the new evidence is: erc ¼i learn that up occurs in this branch by a random procedure. you are necessarily the inhabitant of the up branch, this is not a priori, nor is it certain, so your credence will be less than . everett interpretation and sleeping beauty as the procedure is random, p(erc |mwi)¼ / ; p(e r c |st)¼ / as before, so mwi is not confirmed. thus we avoid the absurd result that mwi is con- firmed by any observation. the main aim of this article is to highlight the role of selection effects, and this is what i hope to have just done regarding mwi. but the secondary aim is to defend the selection effect that i think correctly models the case. in mwi, i think the random procedure correctly models the way we acquire our evi- dence. to assume instead that we are more likely to observe an up branch is implausible and unmotivated—up branches are just as hospitable to life, and just as likely to be observed as down branches. i will defend this in section . sleeping beauty i will now offer a parallel analysis of sleeping beauty (elga [ ]). the sleeping beauty problem runs as follows: it is sunday night. sleeping beauty is about to be drugged and put to sleep. she will be woken briefly on monday. then she will be put back to sleep and her memory of being awoken will be erased. she might be awoken on tuesday. whether or not she is depends on the result of the toss of a fair coin. if it lands heads, she will not be woken. she will sleep straight through to wednesday, and the experiment will be over. if it lands tails, she will be awoken on tuesday. the monday and tuesday awakenings will be indistinguishable. sleeping beauty knows the setup of the experiment and is a paragon of probabilistic rationality. note that heads and tails are two possible worlds and the days are centres within those worlds. monday tuesday heads awake tails awake awake when she is woken, what credence should she have that the coin landed heads? some say that her credence in heads should stay at / . call these halfers (lewis [ ]). some say that her credence in heads should fall to / . call these thirders (elga [ ]). this is not to say that every up branch is as likely to be observed as every down branch. the branches might have unequal weightings. this will be matched by unequal probabilities of up and down in st. mwi will only be confirmed by observing up if the probability that this branch is up given mwi is greater than the probability that this branch is up given st. this would require a selection effect favouring up that is not reducible to the branch weight. experiments have not shown such favouring. nevertheless, those worried by unequal weightings can regard my arguments as applying only to the simple case in which there are equal weights. d. j. bradley a plausible sounding argument (which i will reject) for thirding runs as follows: the technicolour beauty argument the difficulty in the sleeping beauty problem comes from the fact that beauty has no expression that allows her to refer uniquely to the different days. let’s allow her to refer uniquely to the different days by making them subjectively distinguishable. suppose that she sees a coloured piece of paper that is either red or blue on each day. if she is woken once (heads), she sees either a red or blue piece of paper with probability . . if she is woken twice (tails), she sees a red piece of paper on one day and a blue piece of paper on the other. beauty knows all this. suppose beauty observes the red piece of paper. e¼there is a wakening on which the red paper is observed. (the colour of the paper on any given day is independent of the coin flip, so the additional information regarding the coloured paper doesn’t affect what beauty should believe about the coin flip. so beauty’s credences in this case should match her credences in the original sleeping beauty.) does e confirm tails? this amounts to: is p(e|tails) > p(e|heads)? yes. tails says that both the red and blue paper will be observed, so p(e|tails)¼ , while p(e|heads) is / . it follows from bayes’ theorem that p(heads|e)¼ / , just as thirders claim. technicolour beauty monday tuesday heads red or blue tails red or blue red or blue (whichever wasn’t seen on monday) notice that it didn’t matter that red paper was observed rather than blue paper. both outcomes had a probability of given tails, both outcomes had a probability of / given heads, so both confirm tails. we get the result that any possible evidence confirms tails. the argument above is based on (titelbaum [ ]), who identifies the problem in sleeping beauty as the inability to express on sunday the evidence learnt on monday. he fixes this problem by allowing that the awakenings are distinguishable, while not allowing that this distinguishability helps beauty figure out which day it is. (i should add that titelbaum introduces technicolour beauty within a more general formal framework, and does not express the argument as i have done above. nevertheless, he uses the likelihoods p(e|tails) > p(e|heads) to generate his thirder position. (see ibid., p. , table , assumption and table assumption ). i don’t dispute the values. i dispute that e expresses beauty’s total evidence.) everett interpretation and sleeping beauty the kind of thinking in technicolour beauty also seems to be endorsed by thirders papineau and durà-vilà ([ a], [ b]) in their dispute with peter lewis ([ ], [ ]). lewis had argued that sleeping beauty and the everett interpretation were sufficiently analogous that everettians had to be com- mitted to the halfer answer in sleeping beauty. (i will argue that he is right.) in both cases, the two hypotheses are that there is one location of observation versus two locations of observation. and in both cases, the agent doesn’t know which location she is at. to use lewis’s apt phrase, she gets lost in the branches. quantum mechanics sleeping beauty branch branch monday tuesday st up or down heads awake mwi up down tails awake awake adding the coloured paper and removing the names of the days makes the analogy even more transparent: quantum mechanics technicolour beauty branch branch day day st up or down heads red or blue mwi up down tails red blue even though both up and down are certain to happen given mwi, quantum theory requires non-trivial probabilities regarding which branch is observed, so everettians have gone to great lengths to devise ways of assigning non-trivial probabilities to up and down (saunders [ ]; vaidman [ ]; greaves [ ]; papineau [ ]; wallace [ ]). peter lewis argued that if there really are non-trivial probabilities in mwi regarding which branch is observed, then by analogy there should be non-trivial probabilities in tails (in sleeping beauty) regarding which day is observed. if so, we could model tails as a case in which a second fair coin is flipped to determine whether beauty will be woken on monday or tuesday. if so, the halfer answer is clearly correct. but papineau and durà-vilà argue that although the outcomes have non-trivial probabilities in mwi, there is only trivial probability (i.e. prob- ability ) with tails in sleeping beauty. why? because credences should match objective probabilities and ‘the objective probabilities of waking on monday and tuesday are both ’ , ([ b], p. ). this mirrors the technicolour due to the brevity of their discussion, i’m not certain papineau and durà-vilà would endorse the technicolour beauty argument. but it does seem like a natural reading of their papers. if the appropriate probability were , it’s not clear to me what would stop an opponent from responding that by analogy the appropriate probability in mwi is also . papineau and durà-vilà base their argument on the ‘objective quantum probabilities’. but the status of these ‘objective quantum probabilities’ and their connection to rational credence is one of the issues up for debate. d. j. bradley beauty argument that the probabilities of there being a red paper and a blue paper are both given tails; p(e|tails)¼ , while p(e|heads) is / , and thirding follows. i will now argue that the technicolour beauty argument fails to take into account the selection effects, and so assigns the wrong conditional probabil- ities. titelbaum and papineau & durà-vilà seem to take e (i.e., there is a wakening on which the red paper is observed), or something like it, to express the evidence. but the total evidence is stronger than e. the evidence learnt when red paper is observed is not the uncentred proposition that there is an awakening on which the red paper is seen, but the centred proposition that red paper is observed on this awakening. the agent has learnt when it is—it is a day with red paper. i will argue that this has probability / , rather than . the first thing we need to do is ensure that the evidence is a centred proposition: ec¼today is a red paper day. the second thing we need to do is put in the correct selection effect. if heads lands, the selection effect is trivial. as she is only awake on monday, she will see whatever coloured paper is placed before her on monday, so (ec|heads)¼ / . however, in order to determine p(ec|tails), we have to ask: given that beauty is woken twice, what should her subjective probability be that her current time-slice is on a day on which red paper is observed? the answer to this question will depend on whether there is any bias in the selec- tion procedure. suppose first that the procedure is biased towards red paper days. recall this means that if there is a red paper day then red paper is observed. to make this vivid, modify the case so that if tails lands, beauty is woken only on the red paper day, whether it be monday or tuesday. (if heads lands, she is woken only on monday as before, and sees whatever paper is placed before her on monday.) so the new evidence is: ebc ¼i learn that today is a red paper day by a procedure biased towards red paper days. as the procedure is biased towards red paper days, p(ebc |tails)¼ . as p(ebc |heads)¼ / , tails is confirmed. this might appear to give us the confirmation of tails defended by titelbaum and papineau & dura-vila. but they think tails is confirmed whatever observation is made, and this isn’t possible. tails is confirmed if i emphasize that i am concerned with the conditional probabilities on a day the paper is observed. it is a further question how these relate to the sunday probabilities, which i take no stand on in this paper. see footnote . again, it doesn’t matter if the awakening is individuated by the day. we are using subjective probability, so what matters are beauty’s beliefs about what day it is. see footnote . everett interpretation and sleeping beauty the property observed is the property towards which the procedure is biased (red paper days in this case). if instead a procedure which is biased towards red had selected a blue paper day, tails would be eliminated (heads and blue paper would be the only possibilty left). the view that both observations confirm tails requires that the procedure is biased in both ways at once. and this isn’t possible for an agent who can only remember the current day. just as naı̈ve conditionalization failed because an in-branch agent can’t be modelled using a procedure biased towards both up and down, automatic confirmation of tails fails because a within-day agent can’t be modelled using a procedure biased towards both red and blue paper days. suppose instead that there is no such bias towards observing a red paper day. then we have a random procedure—red paper days have the same prob- ability of being observed as blue paper days. erc ¼i learn that today is a red paper day by a random procedure. as the procedure is random, p(erc |tails)¼ / . as p(e r c |heads)¼ / , tails is not confirmed. my main concern is simply to highlight the importance of selection effects. but i also want to defend the answers i favour. i think in this case it is even more plausible than in mwi that the process should be modelled by a random procedure. indeed, we stipulated that given tails, beauty would see a red paper one day and a blue paper the next. the only way the procedure would not be random would be if, on one of the awakenings before seeing the paper, beauty had a reasonable subjective degree of belief that ‘today is a red paper day given tails’ that diverged from %. knowing the setup as she does, it is hard to see how beauty could reasonably believe such a thing. nevertheless, can we give a positive argument that beauty should assign % credence to ‘this is a red paper day given tails’? i will argue in the final section on the restricted principle of indifference that we can. but first i want to clarify my position and its significance. significance of the analogy i have argued that sleeping beauty has the same structure as mwi, shown most clearly by this table, repeated from above: quantum mechanics technicolour beauty branch branch day day st up or down heads red or blue mwi up down tails red blue what follows? peter lewis ([ ], [ ]) argues that everettians must be halfers. i agree. he thinks this is bad news for everettians. i think it is good d. j. bradley news for everettians, but i won’t debate the issue here, as the significance of the analogy runs deeper. the issue isn’t about whether we accept mwi, but whether we gain suspiciously easy evidence for mwi. thirders think that beauty gains on waking some reason to believe that the possible world in which there are more observations (tails) is more probable than the world with fewer (heads). the analogous position regarding mwi is that we gain some reason after branching to believe that the possible world in which there are more observations (mwi) is more probable than the one with fewer (st). as branching is happening all the time, it would follow that we have overwhelming evidence in favour of mwi! for example, suppose i see it is raining, where some quantum probability is responsible for it raining rather than being sunny. according to mwi, it was certain that rain would be observed (in some branch), but according to st it is less than certain. so our everyday observations are constantly confirming mwi. on this reasoning, mwi gets enormous confirmation without the need for modern physics. the ancients could have worked out that they have overwhelming evidence for mwi merely by realizing it was a logical possibility and observing the weather. if thirders are to reject this easy evidence for mwi, they owe us an explan- ation of where the disanalogy lies between sleeping beauty and mwi. this isn’t just a problem for thirders who are everettians, it’s a problem for any thirders who think that evidence for mwi should not be easy to come by. so even those who dismiss the scientific theory that the universe is dividing face the question of what would happen to confirmation theory if it were. the fact that philosophers have been led to some of these problems by science is accidental. interest in personal identity under cases of fission, for example, was not motivated by the invention of fission machines, but by interest in what fission cases tell us about our concept of personal identity. similarly, fission of the world is not only interesting because a scientific theory says that the world really is dividing, but because of what fission cases tell us about our concept of confirmation. the final loose end is to defend the assumption that observers in tails and mwi should assign a probability of % to being each of the two observers. this was necessary to model the cases with a random procedure. adam elga those who accept that evidence for mwi is easy to come by might endorse the self-indication assumption (bostrom [ ]), which provides a priori confirmation of hypotheses with greater populations. bostrom rejects it, but similar positions are defended by bartha and hitchcock ([ ]), dieks ([ ]) and peter lewis ([ ]), who all claim that it cancels out the shift in favour of smaller populations of the doomsday argument. but it is not clear that there is an analogous cancellable shift with regard to mwi. everett interpretation and sleeping beauty ([ ]) has defended a restricted principle of indifference which defends this assumption. indeed, the intuitive case elga uses to motivate his principle is exactly the same as tails in sleeping beauty. i will explain elga’s arguments and defend them from the criticisms of weatherson ([ ]) the restricted principle of indifference i include this section against my better judgment, as it may give the impression that my earlier arguments are based on those in this section. but my main point has been that naı̈ve conditionalization and the analogous thirder argu- ments in sleeping beauty are incorrect. those arguments rely on assumptions about selection effects that are not just false but incoherent - they require that the procedures are biased in both directions. even if the procedures are biased in one direction, the arguments for naı̈ve conditionalization and being a thirder still fail. i do not need to argue for the further point that the proce- dures are in fact random. nevertheless, in this section i will do exactly that. elga motivates his argument with the following scenario—o’leary is locked in the boot of his car all night, knows he will wake at a.m. and a.m., but both awakenings will be subjectively indistinguishable because by a.m. he will have forgotten the a.m. awakening. in both the tails and o’leary scenarios, it is highly plausible that the agent’s credence at each centre should be / . more precisely, elga argues that centred worlds deserve equal credence when: (a) they are in the same uncentred world; and (b) the agents are subjectively indistinguishable. elga’s argument is based on the following thought experiment. suppose an agent named al is in a lab and about to be drugged. if a fair coin lands heads, he will be woken up unharmed. but if the coin lands tails, the scientists will make an exact duplicate of al and put the original in a coma. al and the duplicate will be unable to tell when woken which agent he is. al knows all this. before being drugged, al’s credence in heads should be %, as the principal principle dictates (lewis [ ]). elga argues that after waking, al’s credence in heads should still be %. the reason is that al has ‘neither gained nor lost information relevant to the toss outcome’ (elga, ibid., do not confuse elga’s restricted principle of indifference with a less restricted principle of indifference that would imply equal credence in each awakening: monday & heads, monday & tails, tuesday & tails. as david lewis ([ ], p. , fn ) says ‘this would afford a swift shortcut to elga’s conclusion—much too swift—and elga is wise to have nothing to do with it.’ this is an odd thing for elga to rely on, as he seems to explicitly reject this premise in his earlier paper defending the thirder position. there, he concludes that ‘the manner in which an agent counts her own temporal location as relevant to the truth of some proposition can change over time [. . .] even during a period in which that agent neither receives new information nor suffers a cognitive mishap’ ([ ], p. ). i am grateful to an anonymous referee for stressing this point. d. j. bradley p. ). if this is right, then the restricted principle of indifference follows with fairly minimal assumptions (i refer the reader to elga’s paper for the details). al duplicate heads tails % % weatherson ([ ]) disagrees with elga, and argues that al’s degree of belief in heads should not necessarily remain the same after waking. weatherson offers four considerations in support of his view. i will very briefly go through them and indicate why i am not convinced. firstly, weatherson claims that al gets some evidence on waking—perhaps he experiences certain sensations or has certain thoughts—and this evidence might be relevant to heads, for all he knows. but elga set up the thought experiment so that al and the duplicate are subjectively indistinguishable. this means that any sensations or thoughts al has would also be experienced or thought by the duplicate, so they cannot be relevant to heads. second, weatherson charges that elga is committed to internalism about evidence, which conflicts with the evidence externalism of williamson ([ ]) and campbell ([ ]). moreover, it conflicts with the (epistemic) possibility that such evidence externalism might be true. but i think we can grant weatherson the controversial thesis that evidence externalism is, or might be, true. elga doesn’t need to say that al and the duplicate would have the same evidence. he just needs to say that al and the duplicate would be in the same subjective state, and that one’s credences should depend on one’s subjective state. as al and the duplicate would be in the same subjective state, no part of this subjective state can support heads. third, weatherson charges that al’s degree of belief in heads should change from being risky to being uncertain after the toss. that is, it should be represented by an interval rather than a point probability. (the distinction between risk and uncertainty is due to knight [ ]; the central point is that risk is measurable, and uncertainty immeasurable.) but it would be odd for a risky proposition to become uncertain in this way. uncertainty is most plausible in cases in which we have very little information regarding the proposition. but in this case we have as much information re- garding heads after waking as we did before—we know that it is a fair coin. furthermore, elga ([ ]) has put forward an argument that holding interval probabilities is irrational that i at least find persuasive. the literature on dilation (see seidenfeld and wasserman [ ]) might help weatherson here, but he doesn’t mention it, and a discussion would take us too far afield. everett interpretation and sleeping beauty fourth, and relatedly, even if there is no reason for al to change his cre- dence in heads in one direction or the other after the toss, weatherson sug- gests it may still be reasonable for his credences to change. the absence of a reason to change is not a reason to stay put. but al already does have a reason to stay put—his credence in heads matches the objective chances, and it is widely accepted that credences should match known objective chances. without some defeater for this reason, surely he should stay put. obviously, this has been the quickest of discussions, and there is much more to be said. even if elga’s specific argument can be faulted however, some such restricted principle of indifference seems highly plausible. scientists continue to use principles of indifference to great effect (jaynes [ ]), even if philosophers have not produced a satisfactory justification. as mwi is a scientific theory, it does not seem objectionable to use a principle of indifference, even if we were to lack a solid philosophical justification for it at present. both the many worlds interpretation and sleeping beauty involve learn- ing self-locating evidence. i have argued that the selection procedure by which the self-locating evidence was discovered must be taken into account. in particular, i have argued that when we do so, we find that the observa- tion of the result of a measurement does not automatically confirm the many worlds interpretation. a parallel analysis can also be applied to the sleeping beauty problem. the result is that a certain argument for the thirder position is shown to be problematic. finally, the analogy be- tween sleeping beauty and the many worlds interpretation means that thirders appear to have suspiciously easy evidence that the many worlds interpretation is true. acknowledgements thanks to victor durà-vilà,kenny easwaran, adam elga, branden fitelson, hilary greaves, peter lewis, alan hájek, david papineau, john perry, huw price, mike titelbaum, david wallace, and brian weatherson, audiences at the coffs harbour rationality conference and the university of sydney and two referees for helpful discussion and comments. convent ave. new york ny usa bradleydarren@gmail.com d. j. bradley references bartha, p. and hitchcock, c. 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[ ]: ‘conditionalizing on knowledge’, british journal for the philosophy of science, , pp. – . everett interpretation and sleeping beauty beauty in physics : the legacy of paul dirac ral-tr- - february beauty in physics: the legacy of paul dirac* n. a. mccubbin** in physicists around the world celebrated the centenary of the birth of paul dirac, om, frs, nobel laureate, who was one of the greatest physicists of the th century. he made towering contributions to the formulation of quantum mechanics and he was one of the principal creators of quantum field theory. in he combined relativity and quantum mechanics in the dirac equation, which provides a natural description for the spin of the electron and which led to the prediction, by dirac himself, of the existence of anti-matter. in this article i try to explain, in the simplest terms, these major contributions to physics and to give some flavour of the man himself. . introduction throughout his life paul dirac loved walking. it was his habit, as a young post-graduate in cambridge, to take long walks in the cambridge countryside at the weekend. on one of these walks in the autumn of , probably sunday th september [ ], he was thinking about a paper by a young german physicist, werner heisenberg, which suggested a new approach to quantum theory. the mathematics in the paper had a peculiar feature that heisenberg found disturbing. dirac thought suddenly of a similar feature in classical mechanics, but he couldn’t quite remember the details, and, frustratingly, libraries in cambridge were closed on sundays. it is reasonable to suppose that dirac was at the library’s doors as they opened on monday morning; he checked his hunch and found, to his delight, that the pieces fitted: the feature that the paper’s author had found so disturbing in fact mapped perfectly on to the poisson brackets of classical mechanics. the young post-graduate had discovered the bridge between classical mechanics and a general theory of quantum mechanics. this story of dirac’s discovery is well known, delightful, and all the better for being true, since we have it from dirac himself [ ]. (i will say more about it later.) it occurred at the beginning of a ‘golden period’ in physics to which dirac himself would contribute so much. just eight years later, in , he was a nobel prize winner, fellow of the royal society, and lucasian professor of mathematics at cambridge. he lived until and did outstanding work after . but his place in the pantheon of physics rests on the work of those eight years. in the following sections i describe and discuss dirac’s major contributions to the development of quantum theory, and thus to modern physics. my primary aim is to make the main ideas of dirac’s principal contributions as accessible as possible, so that, for example, the interested physics undergraduate should be able to follow the mathematics very easily, and, i hope, learn something of these great years in the history of physics. there is, therefore, no attempt whatsoever to give a complete or in-depth survey of dirac’s work, which would, in any case, far outstrip my competence. section is devoted to the birth of quantum mechanics in . i describe heisenberg’s odd-looking multiplication rule for quantum quantities and dirac’s discovery that this rule had an analogy in the poisson brackets of classical mechanics. dirac’s discovery leads directly to one of the defining principles of modern quantum theory. ** particle physics department, rutherford appleton laboratory, cclrc, chilton, didcot, oxfordshire, ox qx, united kingdom. e-mail: n.a.mccubbin@rl.ac.uk * to be published in contemporary physics section is a brief summary of the remarkable blossoming of quantum theory that took place in and , which sets the scene for sections and that describe what are, by common consent, dirac’s greatest contributions: the relativistic equation for the electron (which everyone, except dirac, has always referred to as the dirac equation), and the prediction, from the equation, of anti-matter. section is a very light-touch discussion of dirac’s contribution to quantum field theory, which underpins so much of the modern theory of particle physics. as is well known, dirac himself was deeply sceptical of the development of quantum field theory in the second half of the last century, even though he was the originator of several of the key ideas. i have attempted to give enough mathematical detail to give at least some flavour of dirac’s work and style, but i have cut mathematical corners aplenty in the interests of simplicity and accessibility to as wide an audience as possible. . : quantum mechanics the year saw the climax of several years of struggle to turn the early quantum ideas of planck ( , black-body radiation), einstein ( , photo-electric effect; , emission and absorption of radiation), and bohr ( , spectrum of hydrogen) into a fully-fledged theory. bohr’s picture of atomic structure has great heuristic value, even today: the hydrogen atom comprises a positively charged proton round which orbits the much lighter negatively charged electron. only certain discrete orbits (and hence energies) are allowed, and radiation is emitted or absorbed by transitions between these discrete orbits. by much effort and ingenuity had been expended in elaborating bohr’s picture and calculations, and it was well established that: (a) classical physics could not explain atomic structure, for the simple reason that classical physics predicted that electrons orbiting a nucleus was not a stable configuration: any accelerating (by virtue of the orbital motion) electron would rapidly radiate off its energy and collapse into the nucleus; (b) there was something ‘discrete’ (or ‘quantized’) about the atomic world: only certain values of energy, angular momenta,….. were allowed. in particular there must be energy levels which atomic electrons can occupy without radiating, in order to explain the stability of atomic structure; (c) atomic spectroscopy (the frequencies, intensities and polarisations of light from atoms), which provided much of the information about the atomic world, could not be calculated in detail, except in the simplest cases (e.g. the hydrogen atom); (d) the frequency, ν , of a spectral line was assumed to correspond to a transition between discrete energy levels e and e , such that : eeh −=ν , where h is planck’s constant. this formula was found to work very well in those simple cases for which the energy levels (e) could be calculated. it also implied that the observed frequencies should often be simple combinations of each other. for example, in a three-level system with e > e >e , and in which transitions took place between all three levels, there is the simple prediction that ννν += . . . heisenberg’s paper by the summer of heisenberg, although still only years old, had been fully engaged in the battle to tease a proper quantum theory out of spectroscopy for some time. he had worked at göttingen and copenhagen with some of the other leading young physicists, published several papers on quantum theory, and discussed the problems with bohr and einstein. he was mindful of one of the lessons of einstein’s relativity theory: pay careful attention to what is measurable, and how you measure it. a classical approach to the atom would start, as bohr had done, with the electron’s orbit. but electron orbits are not the directly measured quantities. on the other hand spectral lines are observable; wavelengths (and hence frequencies) can be measured. it was, and is, a valuable and powerful technique to seek solutions to problems in classical physics in terms of a fourier series. for example, a position x(t) might be expanded as: ( ) exp( ); ,α α αω ω πν ∞ =−∞ = =∑x t x i t ( ) where ω is the angular frequency (i consider, for simplicity, a system with just a single characteristic frequency). the xα are the coefficients of the expansion, and α takes positive and negative integer values so that all integer multiples of ω participate in the series. consider now a two-level quantum system, see figure . there is only one measurable angular frequency: ee −=ωh , where π /h≡h . it is convenient to define also ω =ω = , and ω = − ω . if we insist on using measurable quantities only, then the fourier series for x(t) has to be: ( ) , ω ω ω ω= + + +i t i t i t i tx t x e x e x e x e ( ) where the xij are expansion coefficients similar to the xα in equation ( ). another quantity y(t) would be written: ( ) . ω ω ω ω= + + +i t i t i t i ty t y e y e y e y e ( ) and what about x(t)y(t)? presumably this is perfectly straight-forward: ( ) ( ) [ ] [ ] . i t i t i t i t i t i t i t i tx t y t x e x e x e x e y e y e y e y eω ω ω ω ω ω ω ω= + + + × + + + ( ) mathematically this multiplication is of course perfectly natural. however, when multiplied out, the expression for x(t)y(t) contains terms like exp( )x y i tω× × . such a term is not a position, x, must of course be a real quantity, so there is a convention (e.g. ‘take the real part’) or constraint (e.g. αα −= xx ) required when writing a real quantity in terms of complex exponentials )exp( tiαω . however, it is algebraically extremely convenient to work with the complex exponential even in classical physics, and mandatory to do so in quantum theory. for a discussion of the significance of ‘i’ in quantum mechanics, see [ ]. figure . two-level system allowed if we continue to insist that only observed frequencies appear in the fourier series, since ω does not correspond to any transition in our simple -level system. taking a cue from his theoretical studies of ‘dispersion’ (scattering of light by atoms) with kramers, heisenberg suggested in his ground-breaking paper [ ] a new rule for multiplication in the quantum world. instead of ( ), heisenberg’s rule gives: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) . i t i t i t i t i t i t i t i t x t y t x y e x y e x y e x y e x y e x y e x y e x y e ω ω ω ω ω ω ω ω ω ω ω ω ω ω + + + + + + = + + + + + + + ( ) stated a little clumsily, the rule is to multiply each ‘ij’ term in the x series by all the ‘jk’ terms in the y series, e.g. the x term gets multiplied by the y and y terms, but not by the y or y term. at first glance equation ( ) may also seem to be littered with frequencies which don’t correspond to actual transitions, but, remembering that ω =ω = , and ω =-ω , the only non-trivial exponential terms are in fact )exp( tiω± , i.e. measurable frequencies only. generalising to a multi-level system, and considering: ............)( ++= tinj njextx ω ( ) ........... .......,jm i t jmy t y e= + + ω then heisenberg’s rule for z(t) = x(t)y(t) is that ..................)( ++= tinm nmeztz ω where ( ) . ω ωω += ∑ nj jmnm i ti tnm nj jm j z e x y e ( ) we note that nmmjjnjmnj eeee ωωω =−+−=+ h/)( for all j, and that heisenberg’s rule therefore guarantees that the same frequencies, and only the same frequencies, appear in the product as appear in the multiplicands. in his paper, heisenberg emphasised this feature of his multiplication rule: ‘..in fact this type of combination is an almost necessary consequence of the frequency combination rules’ [ ]. but there is another striking feature. heisenberg again [ ]: ‘a significant difficulty arises, however, if we consider two quantities x(t), y(t), and ask after their product x(t)y(t). …. whereas in classical theory x(t)y(t) is always equal to y(t) x(t), this is not necessarily the case in quantum theory’. and indeed this ‘significant difficulty’ is immediately apparent in our simple two-level example. for example, according to the heisenberg multiplication rule, the product x(t)y(t) contains the term exp( ( ) )ω ω+x y i t (equation ( )), but there is no term in yx in the heisenberg expression for y(t)x(t). modern readers will no doubt recognise that heisenberg’s multiplication rule, equation ( ), is exactly that of matrix multiplication, but, at the time of writing his paper, heisenberg, in common with almost all physicists of the period, had never heard of a matrix! having stated his multiplication rule, and noted the ‘significant difficulty’, heisenberg proceeded in his paper to apply it to simple cases. significantly and quite deliberately, heisenberg took pains to consider cases involving products like x in which the ‘ xy yx≠ ’ difficulty did not appear, or at least was not manifest. the results looked encouraging. as the second sentence is one of the most pregnant in all science, perhaps one should note it in the original german: ‘während klassisch x(t)y(t) stets gleich y(t)x(t) wird, brauch dies in der quantentheorie im allgemeinen nicht der fall zu sein.’ crucially, he found that the principle of energy conservation survived his weird multiplication rule. he thought he was on to something, and he was right. . . dirac’s contribution in september paul dirac had been a post-graduate research student in cambridge for about two years. born in bristol in , he had been a precocious schoolboy, entering bristol university at the age of , and gaining first-class honours in electrical engineering in . since his mathematical interest and gifts were already clear at school, it is at first sight surprising that he did not study mathematics at university. his father, who was by all accounts a severe and rather forbidding character from the french-speaking part of switzerland, may have insisted that paul should study a subject with good employment prospects, as he had insisted with paul’s elder brother. perhaps paul himself was attracted by the fact that the engineering department was in the same building as his secondary school, so the transition from school to university would be in a largely familiar environment; he was, after all, only sixteen. whatever the reason, paul excelled in the course, particularly its theoretical aspects, and he never regretted his engineering studies. he then tried to get a job a job as an engineer: and failed. however disappointing this may have been personally, it is one of the best things that could have happened for the development of physics. he won a scholarship (by examination) to continue his studies at cambridge, but the scholarship was not enough to support him there. so he stayed in bristol where the university mathematics department invited him to take the undergraduate mathematics course, free of charge. he completed the three-year course in two years, and in , encouraged and recommended by the bristol mathematicians, he obtained a grant from the department of scientific and industrial research, which, when combined with his earlier scholarship, was enough to study at cambridge. cambridge would be his professional home for the next forty-six years. dirac’s supervisor as a research student at cambridge was ralph fowler, who had trained as a mathematician, but who had turned to theoretical physics, and developed a strong interest in the doings of experimentalists. (perhaps not coincidentally, he was also rutherford’s son- in-law.) he had mastered the quantum theory such as it was, and dirac attended his lectures on quantum physics. fowler probably had a better understanding of the latest developments from the continental physicists than anyone else in britain. certainly he had spent the early months of working at the niels bohr institute in copenhagen; bohr had visited and spoken in cambridge in may ; two months later heisenberg also lectured in cambridge; certainly fowler asked heisenberg for early sight of his latest work, and in august fowler asked his young research student, paul dirac, to take a look at the proof-sheets (prior to publication) of heisenberg’s paper. at first reading dirac was not overly impressed. on second reading he focussed on precisely the ‘significant difficulty’ that heisenberg had noted, but not pursued. if the difference between xy and yx is not zero, what is it equal to? dirac considered typical terms in the heisenberg expression for xy-yx: , , , , , , ...... ..... ..................... ...... . ω ω + + − − i t i t x y e y x e ( ) as already noted, heisenberg’s paper was written in german, which up to the middle of the last century had at least equal status to english in academic physics. dirac had already studied with the aid of a dictionary the recently published th edition of sommerfeld’s atombau und spektrallinien. i shall now assume that Ω=− ,nnω where Ω is the (classical) angular frequency of the system, so that Ω= , ω . we now add and subtract the term ])(exp[ , , , , tiyx ωω + . such a term does not conform to the heisenberg product rule since the frequency combination , , ωω + is not guaranteed in general to be one of the observed transitional frequencies. but in this case Ω=− ,nnω , so Ω=+ , , ωω , and we can write equation ( ) as: , , , , , , ...... ( ) ..... ..................... ( ) ...... . i t i t x x y e y y x e Ω Ω + − + − − − ( ) (of course coefficients like x , and y , are simple numbers which obey , , , , xyyx = .) generalising equation ( ), we write: ( ) , , , ( ) , , , ...... ( ) ..... ..................... ( ) ...... . i t n n n n n n i t n n n n n n x x y e y y x e + Ω − − − − − − − + Ω − − − − − − − + − + − − − α β α β β α α α β α β β α α β β α β ( ) we now consider large n and small βα and , and assume that the x and y coefficients can be treated as smoothly varying functions of a continuous variable )( hnj ≡ , so that: ,, , , , , and . n nn n n n n n n n n n dydx x x y y dj dj −− − − − − − − − −− ≈ − ≈h h βα α β β α β α α ββ α in setting hnj = we are of course echoing bohr’s quantization condition for angular momentum, as discussed further below. the two terms of equation ( ) can now be written: , , n n i t i t n n dx e y e dj α α β α α ββ − Ω Ω − − −       h , , . n n i t i t n n dy e x e dj β β α β α βα − Ω Ω − − −   −     h if we further define tΩ≡θ , then i t i t dee i d α αα θ Ω Ω = − and , i t i t dee i d β ββ θ Ω Ω = − and equation ( ) becomes: ,, , , . i t i t n nn n i t i t n n n n dydx de de i e y e x dj d dj d β α βα α β α α β β α βθ θ Ω Ω −− Ω Ω − − − − − −     − −          h the ‘nm’ term of x.y-y.x is obtained by summing over α and β with the constraint that mn =−− βα , i.e. :mn −=+ βα ,, , , , . i t i t n nn n i t i t n n n n n m dydx de de i e y e x dj d dj d β α βα α β α α β β α β α β α β θ θ Ω Ω −− Ω Ω − − − − − − + = −     − −          ∑h ( ) now a term like )exp(, tix nn Ω− αα , summed over α, is redolent of the classical expression for x(t) in equation ( ). assuming, with bohr, that there must be a correspondence, in some suitable limit of large quantum numbers, between the quantum and classical descriptions (the this assumption is actually true for the (important) case of the simple harmonic oscillator, and becomes true for ‘large quantum numbers (n)’ for a general quantum system by virtue of bohr’s correspondence principle. dirac considered a general system (of several degrees of freedom) and used the correspondence principle to justify , ω − = Ωn n . correspondence principle), we now identify such sums in equation ( ) with the classical descriptions, obtaining: , x y y x x y y x i i j j j j ∂ ∂ ∂ ∂ ∂ ∂ ∂ ∂   − − = −    ∂ ∂θ ∂ ∂θ ∂θ ∂ ∂θ ∂    h h ( ) where x and y are the classical descriptions like equation ( ). and it must have been at about this point that dirac took his sunday walk. where had he seen something like equation ( ) before? years later dirac recalled: ‘..i remembered something which i had read up previously in advanced books of dynamics about these strange quantities, poisson brackets, and from what i could remember, there seemed to be a close similarity…..’ [ ]. back at home he searched his notes and books for anything about poisson brackets, but found nothing. it is fanciful but not implausible to imagine that he tried out one or two things on paper: the rate of change of any function, ),( ju θ , which is not an explicit function of time t, is given by: . du u d u dj dt dt j dt ∂ θ ∂ = + ∂θ ∂ ( ) that’s just mathematics. if the angle, θ, and angular momentum, j, are canonically conjugate variables in the sense of classical mechanics, then hamilton’s equations of classical mechanics apply: and , d h dj h dt j dt θ ∂ ∂ = = − ∂ ∂θ ( ) where the hamiltonian, h(θ,j), is the total energy of the system. substituting from equation ( ) into equation ( ) gives: . du u h h u dt dj j ∂ ∂ ∂ ∂ = − ∂θ ∂θ ∂ ( ) the right-hand side of equation ( ) is an example of a poisson bracket. for any two functions ),( ju θ and ),( jv θ the poisson bracket is defined as: ( , ) ,pb u v v u u v dj j ∂ ∂ ∂ ∂ ≡ − ∂θ ∂θ ∂ ( ) and so equation ( ) is just pbyxi ),(h . to recapitulate: in the correspondence principle limit, in which classical and quantum descriptions should coincide, the difference between the heisenberg products of two quantum quantities x,y becomes equal to pbyxi ),(h . i have no idea if dirac went through the reasoning of equations ( ) to ( ) that sunday night, but it seems to me he might have done. he was very familiar with the hamiltonian formalism of classical mechanics and had already published a paper that made use of it [ ]. he had to wait impatiently for the libraries to open next morning, but ‘..i still think that my confidence grew during the course of the night’ [ ]. next morning he looked up poisson brackets in whittaker’s analytical dynamics and ‘…found that they were just what i needed’ [ ]. this was just the kind of connection that dirac was looking for: in place of a strange- looking multiplication rule and the mathematically somewhat fuzzy correspondence principle, the hamiltonian formalism was mathematically precise, elegant, and powerful. of hamilton’s equations are an elegant and powerful formulation of classical mechanics. part of their power resides in the fact that they apply for any pair (q, p) of canonically conjugate variables: qhdtdpphdtdq ∂−∂=∂∂= // and // . for the simple case of a -d harmonic oscillator, ( , ) / / ,h p q p m kq= + where p is the usual momentum and q is the usual spatial coordinate. course he had only proved the connection in a particular limit, using, ironically, the correspondence principle. so he made a leap. in his paper ‘the fundamental equations of quantum mechanics’ [ ] he wrote: ‘we make the fundamental assumption that the difference between the heisenberg products of two quantum quantities is equal to π /ih times their poisson bracket expression.’ (dirac’s italics) so he assumed the equality not just in some limit of large quantum numbers, but always! with this assumption results simply pour out. since the difference between heisenberg products turns up so often, it is convenient to define for quantum quantities: [ ],x y xy yx≡ − ( ) which is referred to as the commutator of x and y. choose x and xp as the canonically conjugate variables, then dirac’s fundamental assumption for quantum quantities u and v is: [ ], ( , ) .pb x x u v v u u v i u v i x p x p  ∂ ∂ ∂ ∂ = = −  ∂ ∂ ∂ ∂  h h ( ) we are free to choose u x= and xv p= , which gives immediately: [ ], ,x xx x x p px x x p i i x p x p  ∂ ∂∂ ∂ = − =  ∂ ∂ ∂ ∂  h h ( ) which is the defining equation of quantum mechanics. from equations ( ) and ( ), the hamiltonian formalism of classical mechanics gives: ( , ) .pb du u h dt = ( ) we obtain the quantum version from equation ( ): [ , ] or [ , ], du u h du i u h dt i dt = =h h ( ) which is the fundamental equation of motion in quantum mechanics. setting u=h we obtain: , dh i dt =h ( ) since, by definition, the commutator of anything with itself is zero. so the hamiltonian doesn’t change with time in quantum mechanics: in other words energy is conserved, just as in classical mechanics. hence energy conservation, which heisenberg obtained only after laborious calculation, falls out with complete generality from dirac’s approach. all this, and much more, dirac showed to his supervisor fowler, who realised the importance of what his graduate student had done. dirac’s paper [ ] was ‘communicated’ to the royal society by fowler (who was an frs) and published in the st december issue of the proceedings of the royal society, just ten weeks after heisenberg’s own paper had been published in z. phys. dirac sent heisenberg a manuscript-copy of his paper in november, and heisenberg wrote back almost by return: ‘i have read your extraordinarily beautiful paper on quantum mechanics with the greatest interest, and there can be no doubt at all that all your results are correct as far as one believes at all in the newly proposed theory.’ [ ] the unknown cambridge graduate student, just years old, had announced himself as a physicist of the first rank. his paper is a plausible candidate for the greatest theoretical- physics paper ever written by a graduate student. a paper ‘communicated’ to the royal society by an frs could be published at the discretion of the appropriate officer of the royal society without the need for an external referee’s opinion, provided the paper was not more than pages long [ ]. dirac’s paper was only pages. . the blossoming of quantum theory: - heisenberg’s paper opened the floodgates. dirac was not the only person to see the key idea it contained. in göttingen max born saw the multiplication rule, thought ‘matrix’, and, with his recent graduate student pascual jordan, derived the key equations [ ] hipx x =, and [ ]hudtdui ,/. =h . born and jordan based their approach explicitly on a matrix representation: the equations they obtained were matrix equations [ ]. there was considerable overlap with the results obtained by dirac, but dirac’s approach was, characteristically, more general. he was thinking of a general ‘algebra’ which quantum quantities, ‘q-numbers’ as he called them, must obey. the new quantum mechanics was developed rapidly in a series of papers by dirac and by born and co-workers, notably in the ‘dreimännerarbeit’ paper of born, jordan and heisenberg, [ ]. pauli [ ] (and, almost simultaneously, dirac [ ]) tackled the hydrogen atom using the matrix approach, obtaining full agreement with the results of the ‘old’ quantum theory of bohr and sommerfeld, a key result in establishing confidence in the new methods. dirac went to copenhagen to work with niels bohr, who presided paternalistically over the revolution he had long hoped for. max born went on a lecture tour of the usa, and spread the new faith to large audiences of american physicists. in early any self- respecting theoretical physicist would have been thinking that he or she would just have to buckle down and learn about matrices. and then in early there was a remarkable development: an austrian physicist, erwin schrödinger, somewhat older than the youthful trio of dirac, heisenberg and jordan, published an alternative theory couched in the familiar terms of a differential equation [ ]. he solved the equation, the schrödinger equation, for the hydrogen atom obtaining the well- established result for the energy spectrum. schrödinger, and probably quite a few other theorists, hoped he had killed off matrices and ‘quantum jumps’ and the like, and restored the traditional mathematics of differential equations to its rightful pre-eminence in theoretical physics. years later, in a lecture at edinburgh in [ ], dirac recalled, ‘when i first heard about the schrödinger theory i did not like it. the reason was that i was perfectly happy with the heisenberg theory’. heisenberg’s reaction was, not surprisingly, similar. then schrödinger himself demonstrated that the two approaches were in fact equivalent [ ]: it was easy to take the solutions of the schrödinger equation, the ‘wave function’, and construct quantities which were precisely the elements which filled the rows and columns of heisenberg’s matrices. mathematically the issue was settled, but the struggle for the precise meaning of the new quantum theory, of the wave function and the quantum jumps, was only just beginning. schrödinger went to copenhagen in the fall of to discuss the situation with niels bohr; the discussions were so intense that schrödinger retreated to his sick-bed. for many of the protagonists, and above all for bohr and einstein, this issue of the meaning, or the interpretation, of quantum theory was a major theme for the rest of their professional lives. not for dirac. he had a very clear and pragmatic, even an ‘engineering’, view of how to use the new quantum theory. as far as he was concerned he said all that needed to be said about ‘interpretation’ in a paper he published at the end of entitled ‘the physical interpretation of the quantum dynamics’ [ ]. he said later that this paper was his proudest achievement, which is a remarkable statement given the competition from his other achievements! in it dirac developed, with characteristic generality and elegance, his ‘transformation theory’ which showed how to transform quantum quantities from one ‘representation’, for example based on the position, to another, for example based on energy. almost as a by-product he showed that the schrödinger equation was just one particular representation of quantum theory, albeit a particularly useful one, and that the wave function was nothing but the transformation function needed to transform the hamiltonian into its ‘energy’ representation. he also showed that the square (strictly the modulus squared) of the transformation functions gave the physically meaningful probabilities, as born had postulated in mid- for schrödinger’s wave function. he showed further that the basic equation of quantum theory should be ‘first-order’ in the energy. dirac’s faith in his transformation theory would lead to a huge advance a year later, as will be discussed in the next section. it was also in this paper that dirac introduced his famous ‘delta function’. in october dirac was the youngest delegate to the th solvay conference. figure is the famous photograph of that meeting, in which dirac stands right in the centre of the middle row . the conference was dominated by quantum theory and is noteworthy for the first serious discussions on interpretation between bohr and einstein. bohr asked dirac what he was working on currently, and dirac said that he was thinking about how to bring einstein’s special relativity into quantum theory. bohr replied that that was all sorted out already by klein. dirac tried to explain to bohr why that was not the case, but the start of a lecture interrupted them [ ]. three months later dirac had solved the problem to his own satisfaction, making one of the landmark discoveries in th century physics. with a typographical error in the last equation on p. of [ ]! actually there are two photographs extant. the most obvious difference is that in figure pauli (back row, fourth from right) is looking to his right, and in the other photograph he is looking much more to the front. figure . the th solvay conference, october . dirac is in the middle of the second row, with einstein and lorentz seated in front of him. to dirac’s left are compton, de broglie, born, and bohr. schrödinger (with spectacles and bow tie) is standing in the back row behind dirac’s left shoulder. to schrödinger’s left are verschaffelt, pauli, heisenberg, fowler, and brillouin. of the twenty-nine participants, seventeen were past or future nobel prize winners. acknowledgement: the living archive, manchester university. . the dirac equation: schrödinger’s approach to quantum theory started from the expression for the total non- relativistic energy of a particle of mass m in a potential v: . ev m p =+ ( ) replacing px (we consider just one dimension) by the differential operator xi ∂∂− /h , and introducing a function (the ‘wave function’ ) for the operator to operate on gives: , ))(( ψψ ψ ψψψ ev xm ev x i x i m =+ ∂ ∂ −∴ =+ ∂ ∂ − ∂ ∂ − h hh ( ) which is the (time-independent) schrödinger equation in one dimension. generalising in an obvious way to three dimensions and setting v to the electrostatic coulomb potential, schrödinger then solved for the hydrogen atom, and obtained the same energy levels as the old bohr theory, which agreed, roughly, with experiment. in developing his theory in the winter of / schrödinger had been more ambitious. he had started from the relativistic expression: . ecmcp o =+ ( ) he then introduced the electromagnetic potential (in a relativistically covariant way, the details of which are not important here), replaced p by the appropriate differential operator, and solved the resultant differential equation. he abandoned this approach only because it gave an energy spectrum that disagreed with the experimental results: of course since he was using a relativistic approach he was seeking closer agreement with experiment than the simple non-relativistic bohr theory. dirac considered that any attempt to develop relativistic quantum theory directly from equation ( ) was doomed from the outset: not because it is an incorrect relativistic equation (it isn’t!), but because it transgressed his transformation theory of which he was so proud. that theory required that one must use an equation that is first order in e. very well: . ecmcp o =+ but this is unsatisfactory from the perspective of ‘relativity mathematics’ which requires that e and p should appear in an equation in the ‘same way’, reflecting the way in which relativity treats time and space on an equal footing mathematically. what dirac really wanted was an equation like: , ecmpc o =+ ( ) which satisfies all dirac’s mathematical requirements, but is, unfortunately, wrong! the essence of dirac’s problem was simply that: cmpccmcp oo +≠+ , and, in general: baba +≠+ (for non-zero a and b), as everyone learns (or should learn) at school. at which point mere mortals give up. geniuses try harder. the essence of the equivalence between the schrödinger and heisenberg theories lies in the fact that, for any f(x), ( )( / ) ( ) ( / ) . ( ) ( )x i x f x i x x f x i f x− ∂ ∂ − − ∂ ∂ =h h h , which is obviously analogous to x xxp p x i− = h . let us introduce ‘numbers’ and dd (‘d’ for dirac, say) and consider: ( ) ( )( ) ( ) . d a d b d a d b d a d b d a d d ab d d ba d b d a d d d d ab d b + = + + = + + + = + + + now let us suppose that these d ‘numbers’ obey: " " =d , " " and " " =+= ddddd , then indeed: bdadbababdad " "" " i.e. " "" ")( +=++=+ . thus, similarly to heisenberg in his breakthrough paper [ ], dirac needed a funny ‘multiplication rule’ so that , but rather " "d d d d d d d d≠ + = . and, just as in heisenberg’s case, matrices will do the job. for example, we can choose: , and       =      − = dd so that: " ", " ", and " ". d d d d d d             = × = = = × = =           − −            −              + = × + × = + = =             − − −              so, in summary: ecmpc       =      +      − ( ) has the mathematical structure dirac wanted (equation ( )), and satisfies: , p c m c e       + =            ( ) as required by relativity, equation ( ). in fact that isn’t quite general enough because the momentum p is a vector quantity with three components that so ,, zyxzyx ppppppp ++= . hence dirac’s problem was actually to find four matrices, , , ,α α α α such that: ( ) (" " " " " " " " ) " "x y z x y zp c p c p c m c p c p c p c m c eα + α + α + α = + + + = . so the matrices must satisfy " "iα = and " "i j j iα α + α α = for ji ≠ . it turns out that this can’t be done using ‘ x ’ ( rows, columns) matrices. in later years dirac always said that he was slightly embarrassed that it took him some time to find the answer: you have to use ‘ x ’ matrices, for example: ; ; ; i i i i −               −       α = α = α = α =        − −         − −        which satisfy the conditions on the α ’s, as can be checked by straightforward matrix multiplication. hence we can indeed write: " "x y zp c p c p c m c eα + α + α + α = , ( ) where ‘ ’ is the x unit matrix. to obtain the quantum mechanical equation, we replace xp by xi ∂∂− /h , and similarly for yp and zp , and give the differential operators a wave function to operate on: ( ) " "i c m c e x y z ∂ψ ∂ψ ∂ψ − α + α + α + α ψ = ψ ∂ ∂ ∂ h ( ) which is the (time-independent) dirac equation. but what sort of equation is this? to be meaningful the wave function, ψ, must be not only a function of x, y, and z but must also cater somehow for the matrices, α . if we take: ( ) ),,(),,( zyxfazyxf a a a a =             =ψ then the α matrices multiply the column vector (a) to give another column vector, and the dirac equation is finally revealed as a set of four (coupled) partial differential equations. so the mathematics is now meaningful; but what is the physics of these matrices and column vectors? to answer this we recall yet another development of that remarkable period in physics. in order to understand atomic spectra in ever greater detail, two dutch physicists, goudsmit and uhlenbeck, had proposed in that the electron had an ‘intrinsic’ two- valued quantum number, which could be thought of as a kind of intrinsic ‘spin’ in that it combined with the orbital angular momentum quantum number in a way which was similar to the combination of classical angular momenta. pauli had shown that the mathematics of this ‘spin’ was conveniently handled using ‘ x ’ matrices. dirac knew this, indeed had probably discovered these spin matrices for himself [ ], and he showed that the solutions of his equation described this ‘spin’ in a completely natural way. before the discovery of the dirac equation the spin had to be grafted on to theory in a rather ad hoc fashion. it is important to emphasise, however, that dirac did not set out to describe spin. as described above, he was driven by the requirements of his transformation theory and relativity. in his edinburgh lecture dirac recalled: ‘it was a figure . the plaque commemorating dirac in westminster abbey. the dirac equation is written in a very compact notation, and in units in which .c= =h great surprise to me when the spin turned up in that way. i was just trying to get a satisfactory relativistic theory for a particle’[ ]. indeed; but as soon as he found himself playing around with matrices he must surely have started thinking that this would have something to do with spin in the end. dirac’s paper ‘the quantum theory of the electron’ was completed just before christmas , and published in january [ ]. the paper contained the derivation of the equation itself, along the lines described above (although much more succinct!), proof of the lorentz covariance of the equation, and the demonstration that the equation implies directly and naturally all the previously obtained relativistic and spin-dependent corrections to the hydrogen energy spectrum. this paper is rightly considered one of the very greatest in all physics. the dirac equation (in compact notation) is inscribed on the plaque commemorating dirac in westminster abbey, see figure . it is the only equation in the abbey. electron ‘spin’ has several intriguing properties. as already mentioned, it can take on only two values, which is what is meant by saying it has spin ‘½’, the two possible values being + / h and – / h . mathematically the spin has another surprising property: you have to rotate by two complete revolutions ( π) in order to get back where you started. this is in contrast to normal experience of everyday objects that only have to be rotated by one complete revolution ( π) to return to the original state. in fact it is possible to construct macroscopic examples that have this π property: what is required is that an object is connected in a certain way to its surroundings. a demonstration can be seen at http://heplocal.rl.ac.uk/mccubbin/public/rotate.mpg. a good way to think about this is that each π revolution multiplies the electron mathematics by – . this factor of – has utterly profound significance: if one considers the mathematics of two electrons, the operation of interchanging them is the same as the operation of a π revolution on one of them. a macroscopic example can be viewed at http://heplocal.rl.ac.uk/mccubbin/public/interchange.mpg. so the two-electron mathematics is multiplied by – if you interchange the two electrons. this has the direct consequence that two electrons cannot occupy the same (quantum) state, which is the pauli exclusion principle . so an energy level in an atom (strictly an energy level with orbital quantum number ) can be occupied by at most two electrons: one with spin + / h and one with / − h . if a state could hold an arbitrary number of electrons the lowest-energy state of any atom would consist of all the electrons in the lowest energy state, and there would be no chemistry, no elements, and no life, which is what i mean by ‘utterly profound significance’. this property of electrons (and of all spin − ½ particles) was used by dirac in his next great advance. let ( )αψ denote the wave function for the first electron, ( ), having quantum numbers denoted by ‘α’. we require that the total wave function for two electrons, ( , )Ψ , is multiplied by – when the two electrons are interchanged, i.e. ( , ) ( , ).Ψ = −Ψ this requirement is satisfied by ( , ) ( ) ( ) ( ) ( ).Ψ = −α β β αψ ψ ψ ψ but if the two electrons have the same quantum numbers (i.e. α=β ), ( , )Ψ is identically zero. thus two electrons cannot have the same quantum numbers, which is the pauli exclusion principle. this is the argument, based on the ‘anti-symmetry’ of the wave function, as given by dirac [ ]. the energy distribution for a gas of particles requiring this anti-symmetry was obtained a little earlier by fermi [ ]. such particles are said to obey fermi- dirac statistics. in fact jordan had developed the relevant theory before either fermi or dirac, and had sent a paper to born, as editor of zeitschrift für physik, at the end of . born was about to leave for his lecture tour in the usa and packed jordan’s paper in his suitcase…… where, to his great embarrassment, he found it several months later, by which time fermi and dirac had done their work [ ]. http://heplocal.rl.ac.uk/mccubbin/public/rotate.mpg http://heplocal.rl.ac.uk/mccubbin/public/interchange.mpg . anti-matter: in the introductory remarks of the paper on the dirac equation [ ], the author noted that previous work to incorporate relativity into quantum theory (the work which bohr felt had sorted it out) had two problems: the equation used wasn’t first-order in the energy, and the solutions allowed both positive and negative energies. as dirac emphasised, negative energies could not be ignored in quantum theory as they could be in classical physics, because transitions between energy levels were the very essence of quantum theory, and so one had to face up to transitions to a bottomless pit of negative-energy levels. as discussed above, the dirac equation is, triumphantly, first-order in the energy. but the problem of negative energies remains. the origin of the problem is simple. in taking the square root of the relativistic equation: p c m c e+ = both positive and negative energies are allowed, just as the number has two square roots: + and – . despite his brilliant manipulations to obtain a first-order equation for e, dirac did not avoid this second problem. his (matrix) equation relating e, p and m was indeed constructed to ensure that it was consistent with p c m c e+ = , and so it is not too surprising that the dirac equation yields solutions with both positive and negative energies. in dirac proposed a solution [ ]: if each negative-energy state were filled by two electrons then the pauli exclusion principle would forbid any transition to negative energy, since each negative- energy state would already hold its maximum number of electrons. this solves the problem, but at a price. nature’s ground state, the vacuum, now becomes a ‘sea’ of filled negative-energy states, with infinite (negative) electric charge. dirac argued this would not pose a problem for the equations of electromagnetism provided charge in those equations was interpreted as change of charge with respect to this infinite sea. but this picture of the vacuum raises another question: what was there to stop a deposit of energy raising one of the electrons in a negative-energy state into a positive-energy state? certainly there’s an energy gap to be overcome: the positive-energy states start at cm+ and the negative states at cm− , but a photon of energy cm (or greater) has enough energy to overcome this gap. the answer is that, given enough energy, nothing can stop such a process, and an electron can be ‘lifted’ out of the negative-energy sea into a positive-energy state. what then are we to make of the negative-energy sea when it isn’t quite filled, but when there is an unfilled ‘hole’ in the negative-energy states? the negative-energy states have now one more unit of positive charge (since the electron charge is negative) than when completely filled. dirac showed that such an unfilled sea did indeed behave like a positively charged particle in his equation, see figure . but what positively charged particle? in there was only one known fundamental particle with the opposite charge to the electron: the proton. dirac therefore suggested that a ‘hole’ in the negative-energy sea was in fact a proton. the proton mass is, however, some times larger than the electron mass, and dirac had no explanation for such a gross asymmetry. however, there was a certain appealing economy in this interpretation: the two known (at the time) elementary particles, the electron and the proton, were both described by the dirac equation. in the first edition ( ) of his classic textbook ‘the principles of quantum mechanics’, dirac wrote, ‘we assume that these unoccupied negative-energy states are the protons.’ in the second (and subsequent) editions he changed exactly one word. for all its economy, nobody liked very much the proton interpretation. a clinching argument was provided by oppenheimer [ ] and tamm [ ], independently, who showed that the hydrogen atom, consisting of an electron and negative-energy ‘hole’ (the proton), would annihilate essentially immediately into photons, in striking contradiction to experimental observation! in dirac followed the inexorable logic of his mathematics: the natural prediction of his equation was that the positively charged particle arising from a ‘hole’ in the negative- energy states should have the same mass as the electron. in a paper entitled ‘quantized singularities in the electromagnetic field’ [ ], he proposed ‘a new kind of particle, unknown to experimental physics, having the same mass and opposite charge to an electron’. this particle, the anti-electron or positron, did not remain unknown to experimental physics for long: it was discovered by the american physicist anderson in . in making his proposal dirac was of course doubling the number of particles in nature, since this idea of anti-particle partner should presumably apply to protons, as dirac stated explicitly, and as has subsequently been abundantly confirmed by experiment for all particles. in dirac was awarded, jointly with schrödinger, the nobel prize in physics for ‘..the discovery of new and fruitful forms of atomic theory’. the nobel committee had made no award in physics for , delaying until when they awarded the prize to heisenberg. thus the three pioneers of the revolution in quantum theory were all in stockholm together to receive their prizes. it was the first time the nobel committee made awards for work that was fundamentally theoretical in nature, rather than for work in experimental physics or for theoretical work which bore very directly on experiment. famously, einstein won the prize in for ‘..services to theoretical physics, and especially the discovery of the law of the photo-electric effect’. not for relativity! whilst no one questioned that the winners deserved their prizes, there was some discontent that certain others, principally born and pauli, had not also been recognised. heisenberg in particular was very unhappy that born had been overlooked. amends were made when pauli won in , for the exclusion principle, and born in , for his contributions to quantum mechanics [ ]. the nobel prize was the most important, but not the first, official recognition dirac received: he was elected to the royal society in (on the first occasion he was a candidate for election, which is extremely rare), and he had been appointed to the lucasian indeed, the secretary of the swedish academy of sciences wrote to einstein to emphasise that the nobel committee had awarded him the prize ‘..without taking into account the value which will be accorded your relativity and gravitation theories after these are confirmed in the future’ [ ]. figure . sea of filled negative-energy levels with one ‘hole’, which behaves like a positively-charged particle. professorship in mathematics at cambridge in , in succession to sir william larmor. (the lucasian professorship was established in . the second holder was sir isaac newton. the current, seventeenth, professor is stephen hawking.) . dirac and the birth of quantum field theory: by it was clear that there was something particle-like about light, i.e. about the electromagnetic field. that the energy of light had a discrete aspect, ,ωh=e had been the starting-point for quantum theory at the turn of the century in the work of planck on black- body radiation ( ) and of einstein on the photo-electric effect ( ). however, the idea of a ‘particle of light’, with both energy and momentum, took some time to emerge. einstein was fully convinced only in when he showed, from an analysis of the fluctuations of gas molecules emitting and absorbing radiation, that the light quanta must also be fully directional, i.e. carry momentum as well as energy. (as pais has noted, it is striking that the father of relativity took twelve years before he was prepared to publish / alongside p c eω ω= =h h [ ]). not everyone was as convinced as einstein, but in the american physicist arthur compton obtained conclusive experimental verification of the light quantum, or photon, as a carrier of both energy and momentum from a study of the scattering of light by electrons (the compton effect). so it was of course hoped that the new quantum ideas of heisenberg et al. would have something to say about light and the photon. as a first step, born and jordan showed, at the end of their first paper [ ], that maxwell’s equations of electrodynamics could be written and manipulated in matrix form. in the born, heisenberg, jordan ‘dreimännerarbeit’ [ ], the last section, written by jordan, was devoted to an application of the new quantum mechanics to a vibrating string. the authors considered it ‘particularly encouraging’ that the result obtained for the mean-square fluctuation in the energy contained both ‘wave’ and ‘particle’ terms, exactly as einstein had obtained for radiation using an argument based on thermodynamic equilibrium and planck’s formula for black-body radiation. the authors may have found this ‘particularly encouraging’, but in later years jordan commented ruefully that he felt that nobody had read this section of the ‘dreimännerarbeit’, and those who did didn’t want to believe it [ ]. dirac turned his attention to radiation and the new quantum mechanics during his stay at the niels bohr institute in copenhagen in . he had just worked out his ‘transformation theory’ [ ], which, as noted above, he viewed as a general and powerful formulation of quantum theory, including how to extract physically meaningful probabilities from the theory. it was of course axiomatic that the sum of all those probabilities for the system under consideration should be one. but suppose one considered, instead of a single system, an ensemble of n particles. any observation of the ensemble would find n particles in state , n in state , etc., such that nnn =++ ..... . of course ,..., nn must be integers. could this be guaranteed in the new quantum mechanics formalism? dirac showed how this question could indeed be answered in the affirmative, using an almost magical inter-weaving of all his quantum ideas: the analogy with the hamiltonian formalism of classical mechanics, commutation relations, and his transformation theory. it is of course clear that, in order to guarantee that ,..., nn are always integers, one must ensure that any changes in these occupation numbers take place in units of . so dirac introduced creation and annihilation operators, which increase or decrease an occupation number by . dirac then applied this formalism to an ensemble of photons (i.e light) perturbed by an atom that emits or absorbs photons. in order to treat this problem he introduced the idea of a ‘ground state’ containing an infinite number of non-observable photons and which acts as a ‘source’ of emitted photons or as a ‘sink’ for absorbed ones. (this idea clearly anticipates the ‘sea’ of electrons filling the negative-energy states that he used a few years later in interpreting the dirac equation.) he then obtained expressions for the probability that the atom would absorb or emit a photon. dirac’s formalism showed that photon emission could either be induced by an electromagnetic field (‘stimulated emission’), or could take place when no field was initially present (‘spontaneous emission’). ten years earlier einstein had shown that both emission processes must indeed be present in order to maintain thermal equilibrium between the atoms and radiation. dirac’s work showed how quantum theory explained einstein’s results, and further how the intrinsic atomic transition probabilities could actually be calculated. (einstein’s theory left these transition probabilities undetermined.) from the perspective of quantum theory, the existence of spontaneous emission can be traced directly to the commutation relation between the creation and annihilation operators, which is in turn a direct consequence of the fundamental relation [ ] hipx x =, . working through this provides a moment when even the ordinary practitioner can know some of the thrill which creators like dirac must have experienced. (see, for example, [ ].) dirac’s paper entitled ‘the quantum theory of the emission and absorption of radiation’ was ‘communicated’ to the royal society (by bohr, a foreign member) at the end of , and published in [ ]. in effect, he had ‘quantised’ the electromagnetic field, and his paper marks the start of quantum field theory and, in particular, of quantum electrodynamics. quantum field theory was developed rapidly through the ’s with contributions from a galaxy of theorists: jordan, pauli, heisenberg, fermi, wigner, klein, weisskopf, and dirac himself. however, serious and profound difficulties were encountered in the form of infinite results from the perturbative calculations. as is well known, the resolution of these infinities had to wait until after the second world war, and the pioneering work of feynman, schwinger, and tomanaga, all of whom were inspired directly by some of the earlier work of dirac. the whole story is told wonderfully by schweber [ ]. that resolution requires the procedure of ‘renormalisation’ in which, in effect, the infinities are absorbed into the physical values of mass and electric charge. renormalisable quantum field theories now provide the theoretical framework for all of particle physics. as is also well known, dirac was profoundly unsympathetic to the whole renormalisation programme, viewing it as mathematical chicanery. infinite results should be faced directly, and not removed by convenient definition. in his last published remarks in [ ] he returned to this theme in a lecture entitled ‘the inadequacies of quantum field theory’. written in dirac’s precise and unemotional prose, it is, nevertheless, an impassioned and poignant lament about the way quantum field theory had evolved. he urged that the correct approach must be to find an appropriate hamiltonian; that the remarkable agreement with experiment achieved by the renormalisation approach in quantum electrodynamics may, nevertheless, be illusory, just as bohr’s original quantum theory of the hydrogen atom was fundamentally flawed despite its impressive agreement with experiment; that the discovery of the dirac equation showed the benefits of adherence to sound mathematical principles; and that he planned to continue his programme as long as he could. his audience listened, no doubt respectfully, but almost certainly disagreed. in the twenty years since that lecture the triumphant march of renormalisable quantum field theory has continued. but a quantum theory of gravity has resisted the renormalisable approach, and may well require something fundamentally different, like ‘string theory’. so dirac’s intuition may yet prove to be correct. . vignette when asked, in , to state his philosophy of physics, dirac wrote on the blackboard, ‘physical laws should have mathematical beauty’. the precision and conciseness of the statement are typical of him. he took great pains in what he wrote and how he wrote it. notation matters: dirac introduced the symbol h to save writing myriad factors of π , and, more importantly, his ‘bra’ and ‘ket’ notation for quantum states is now standard. his classic textbook, ‘the principles of quantum mechanics’, is now in its th edition ( ), and has not been out of print since it was first published in . nor has the book been re-set, so the th edition looks very much like the first, and indeed significant passages are word-for-word identical. for example, the discussion of photons and interference in a set-up like young’s double-slit is almost unchanged between the first and fourth editions. the first edition already contains the famous sentences: ‘each photon then interferes only with itself. interference between two different photons can never occur’. of course dirac did make certain changes. for the second edition in he changed the sentence ‘we assume that these unoccupied negative-energy states are the protons’ to ‘we assume that these unoccupied negative-energy states are the positrons’, and he added a chapter on quantum electrodynamics. in the third edition ( ) he introduced the ‘bra’ and ‘ket’ notation. for the fourth ( ) he re-wrote the chapter on quantum electrodynamics. it is indeed the case that his cambridge lecture course on quantum mechanics consisted in part of dirac reading out sections of his book. dirac’s logic was no doubt that he had taken great pains to explain quantum mechanics as clearly as he could in his book, so why should he use a less good explanation? this logical approach certainly carried over into aspects of his social interactions and has been the source of many ‘dirac stories’ of which a reasonable selection can be found in [ ]. as part of the celebrations of the centenary of his birth the iop prepared a set of six posters about dirac’s work in the style of manga comics [http://education.iop.org/schools/supteach/dirac.html]. at the bristol celebration in august his daughter margit was interviewed by the bbc and asked what her father would have thought of such a depiction of his work. she replied that he would have loved it, and added that when the weekly comic section of the newspaper was delivered to the dirac household one was ill-advised to get in her father’s way in his dash to get it! it makes a charming counter-point to the usual picture of the rather taciturn theorist. dirac retired from the lucasian chair at cambridge in , at the statutory age of . he held an emeritus professorship in florida from , and died there in . a plaque was placed in westminster abbey in , see figure . it has the simplicity, elegance and conciseness that he always sought. in the first dirac memorial lectures in , steven weinberg, nobel prize winner for his work on the quantum field theory of weak and electromagnetic interactions, gave a lecture entitled ‘towards the final laws of physics’ in which he described some of the latest ideas on ‘string theory’. he closed by saying, ‘i don’t know, of course, whether dirac would think that the mathematics of string theory is sufficiently beautiful to make it likely that it will survive as part of the final laws of physics. he might agree with that, and he might not agree with that, but i don’t think he would disapprove of what we are trying to do’ [ ]. acknowledgements i thank the organisers of the british association meeting for the invitation to talk on dirac, which sowed the seeds for this article, and all those who have provided feedback and comments on that talk at the ba and subsequent venues. i am particularly grateful to alan walker of edinburgh university for making his recording of dirac’s lecture available, by the th edition the second sentence has been changed to ‘interference between two different photons never occurs’, which is hardly a significant change. in fact it is interesting that dirac did not add any further comments for the th edition, since he must have been preparing it around the time of the furore (among physicists) over the hanbury-brown twiss experiments on intensity interferometry [ ]. dirac’s statements are perfectly correct in the context of young’s double-slit and similar experiments, but need some qualification when ‘higher-order correlations’ are measured, as in the hanbury-brown twiss experiment. on the other hand it is entirely typical of dirac to avoid unnecessary verbiage: his statements, taken in context, were correct. if others chose to mis-interpret or mis-apply them, that was hardly his fault! http://education.iop.org/schools/supteach/dirac.html and to robin marshall of manchester university who digitised the recording and provided several sound-bites. i am also grateful to robin devenish of oxford university for the opportunity to peruse a first edition of dirac’s the principles of quantum mechanics. i have leant heavily on two sources: van der waerden’s compilation of, translation of, and commentary on some of the key papers in his sources of quantum mechanics [ , , , ], and the six-volume encyclopaedic work on the historical development of quantum theory by mehra and rechenberg [ , , ]. for filling out aspects of dirac, both his life and his work, i have often consulted helge kragh’s dirac: a scientific biography [ ]. finally, although it is not properly an acknowledgement, i want to mention the pleasure there is to be had from reading dirac’s original papers. they are not always easy to read - dirac never uses a single superfluous word – but there are passages that have an almost poetic quality. any physicist interested in dirac’s work should start there [ ]. references [ ] mehra, j., and rechenberg, h., , the historical development of quantum theory, volume , part , p. footnote . (new york, heidelberg, berlin: springer-verlag) [ ] dirac, p.a.m., , recollections of an exciting era, pp - . in history of twentieth century physics, proceedings of the international school of physics ‘enrico fermi’, varenna , edited by c.wiener (new york: academic). [ ] yang, c.n., , square root of minus one, complex phases and erwin schrödinger. in schrödinger: centenary celebration of a polymath, edited by c.w.kilminster (cambridge university press). [ ] heisenberg, w., , Über quantentheoretische umdeutung kinematischer und mechanischer beziehungen. z. phys., , - . a translation of this paper is available in van der waerden, b.l., , sources of quantum mechanics (north- holland publishing company). [ ] dirac, p.a.m., , the adiabatic invariants of the quantum integrals. proc. roy. soc. a, , - . [ ] dirac, p.a.m., , the fundamental equations of quantum mechanics. proc. roy. soc. a, , - . [ ] holt, t.j.p., , personal communication. i am grateful to dr. holt, the current editorial & review coordinator for the proceedings royal society a, for his speedy responses to several queries on the processing of dirac’s papers. [ ] letter heisenberg to dirac, nov . quoted in [ ] p. , footnote . [ ] born, m., and jordan, p., , zur quantenmechanik. z. phys., , - . a translation of this paper, except the last chapter, is available in van der waerden, b.l., , sources of quantum mechanics (north- holland publishing company). [ ] born, m., heisenberg, w., and jordan, p., , zur quantenmechanik ii. z. phys., , - . a translation of this paper is available in van der waerden, b.l., , sources of quantum mechanics (north-holland publishing company). [ ] pauli, w., , Über das wasserstoffspektrum vom standpunkt der neuen quantenmechanik. z. phys., , - . a translation of this paper is available in van der waerden, b.l., , sources of quantum mechanics (north- holland publishing company). [ ] dirac, p.a.m., , quantum mechanics and a preliminary investigation of the hydrogen atom. proc. roy. soc. a, , - . [ ] schrödinger, e., , quantisierung als eigenwertproblem (erste mitteilung). annalen der physik ( ), , - . this is the first in a series of six papers on ‘wave mechanics’ published by schrödinger in . they are all available in english translation in: schrödinger, e., , collected papers on wave mechanics ( rd edition) (american mathematical society). [ ] dirac, p.a.m., , lecture in edinburgh. this lecture was recorded and the original recording has been digitized. dirac’s comment on schrödinger’s theory can be heard at: http://heplocal.rl.ac.uk/mccubbin/public/dirac_on_schr.mp , and on spin at: http://heplocal.rl.ac.uk/mccubbin/public/dirac_on_spin.mp . i am very grateful to alan walker (edinburgh university) for making the original recording available, and to robin marshall (manchester university) for the digitized sound-bites. [ ] schrödinger, e., , Über das verhältnis der heisenberg-born-jordanschen quantenmechanik zu der meinen. annalen der physik ( ), , - . this is the fourth paper in the series of six, and is available in english translation, see [ ]. [ ] dirac, p.a.m., , the physical interpretation of the quantum dynamics. proc. roy. soc. a, , - . [ ] reference [ ], p. . [ ] reference [ ], p. and mehra, j., and rechenberg, h., , the historical development of quantum theory, volume , part , p. . (new york, heidelberg, berlin, springer-verlag). [ ] dirac, p.a.m., , the quantum theory of the electron. proc. roy. soc. a, , - . [ ] dirac, p.a.m., , on the theory of quantum mechanics, proc. roy. soc. a, , - . [ ] fermi, e., , sulla quantizzazione del gas perfetto monoatomico. rend. r. accad. lincei ( ), , - , and zur quantelung des idealen einatomigen gases. z.phys. , - . [ ] schucking, e., , jordan, pauli, politics, brecht, and a variable gravitational constant. physics today, october , . [ ] dirac, p.a.m., , a theory of electrons and protons. proc. roy. soc. a, , - . [ ] oppenheimer, j.r., , on the theory of electrons and protons. phys. rev., , - [ ] tamm. i., , Über die wechselwirkung der freien elektronen mit strahlung nach der diracschen theorie des elektrons und nach der quantenelektrodynamik. z. phys., , - . [ ] dirac, p.a.m., , quantized singularities of the electromagnetic field. proc. roy. soc. a, , - . [ ] pais, a., , how einstein got the nobel prize. in subtle is the lord (oxford and new york: oxford university press), pp. - . [ ] friedman, r.m., , quantum theory and the nobel prize. physics world, august , . [ ] pais, a., , the photon. in subtle is the lord (oxford and new york: oxford university press), pp. - . [ ] jordan, p., , interview with t.s. kuhn, p. . archives for the history of quantum physics, niels bohr library, aip, new york. [ ] knight, p.l., and allen, l., , concepts of quantum optics, sections . , . , . and . (pergamon press). [ ] dirac, p.a.m., , the quantum theory of the emission and absorption of radiation, proc. roy. soc. a, , - . [ ] schweber, s.s., , qed and the men who made it: dyson, feynman, schwinger, and tomonaga (princeton university press) [ ] dirac, p.a.m., , the inadequacies of quantum field theory. in [ ]. http://heplocal.rl.ac.uk/mccubbin/public/dirac_on_schr.mp http://heplocal.rl.ac.uk/mccubbin/public/dirac_on_spin.mp [ ] hanbury brown, r., , the intensity interferometer (taylor & francis, london). [ ] kursunoglu, b.n., wigner, e.p. (editors), , reminiscences about a great physicist: paul adrien maurice dirac (cambridge university press) [ ] weinberg, s., , towards the final laws of physics. in elementary particles and the laws of physics (cambridge university press), pp. - . [ ] kragh, h., , dirac. a scientific biography. (cambridge university press). [ ] all of dirac’s papers published in proc. roy. soc. a are available from the jstor archive (http://www.jstor.org/) to members of participating institutions. http://www.jstor.org/ . introduction . : quantum mechanics . . heisenberg’s paper . . dirac’s contribution . the blossoming of quantum theory: - . the dirac equation: . anti-matter: . dirac and the birth of quantum field theory: . vignette acknowledgements working paper series faculty of finance no. the beauty contest and short-term trading giovanni cespa & xavier vives the beauty contest and short-term trading∗ giovanni cespa† and xavier vives‡ november abstract short-termism need not breed informational price inefficiency even when gen- erating beauty contests. we demonstrate this claim in a two-period market with persistent liquidity trading and risk-averse, privately informed, short-term investors and find that prices reflect average expectations about fundamentals and liquidity trading. informed investors engage in “retrospective” learning to reassess inferences (about fundamentals) made during the trading game’s early stages. this behavior introduces strategic complementarities in the use of information and can yield two stable equilibria that can be ranked in terms of liquidity, volatility, and informa- tional efficiency. we derive implications that explain market anomalies as well as empirical regularities. keywords: price speculation, multiple equilibria, average expectations, public informa- tion, momentum and reversal jel classification numbers: g , g , g ∗a previous version of this paper was circulated under the title “expectations, liquidity, and short- term trading”. for helpful comments we thank elias albagli, max bruche, giacinta cestone, hans degryse, marcelo fernandes, itay goldstein, peter hoffmann, harrison hong, peter kondor, jean- paul laurent, olivier loisel, stephen morris, richard payne, ioanid roşu, kristien smedts, gunther wuyts, lian yang, kathy yuan, and participants at numerous seminars and conferences. cespa acknowl- edges financial support from esrc (grant no. es/j x/ ). vives acknowledges financial support from the european research council under the advanced grant project information and competition (no. ) and from project eco - of the spanish ministry of science and innovation at the public-private sector research center at iese. †cass business school, city university london, and cepr. , bunhill row, london ec y tz, uk. e-mail: giovanni.cespa@gmail.com ‡iese business school, avinguda pearson, , barcelona, spain. it might have been supposed that competition between expert profession- als [. . . ] would correct the vagaries of the ignorant individual left to himself. it happens, however, that the energies and skill of the professional investor and speculator are mainly occupied otherwise. for most of these persons are [. . . ] largely concerned, not with making superior long-term forecasts [. . . ] but with foreseeing changes in the conventional basis of valuation a short time ahead of the general public. (keynes, the general theory of employment, interest and money, ) does short-termism breed informational price inefficiency? we find that this need not be the case—even though beauty contests arise—provided that liquidity shocks are per- sistent. we examine this question in a two-period market where short-term, informed, competitive, risk-averse agents trade on private information and to accommodate liquid- ity supply while facing persistent demand from liquidity traders. traders’ “myopia” ranks high on the regulatory agenda, which testifies to policy mak- ers’ concern about the possibly detrimental effects of such myopia on the market. debate over this issue has a long tradition in economic analysis. indeed, short-term trading is the very basis of keynes’s dismal view of financial markets. according to his “beauty contest” analysis, traders’ investment decisions are driven by anticipation of their peers’ changing whims and not by actual knowledge of the companies they trade. as a result, competition among informed traders does not necessarily counteract the actions of unin- formed traders. it has been claimed that this type of behavior introduces a particular form of informational inefficiency whereby traders tend to put a disproportionately high weight on public information in their forecast of asset prices (see allen, morris, and shin while the market presence of traditionally long-term investors such as institutions has steadily increased during the last two decades, their holding period has decreased substantially (see oecd, http: //www.oecd.org/daf/fin/financial-markets/ .pdf). haldane and davies ( ) examine a large panel of uk- and us-listed companies over the period from to ; they find compelling evidence of investors’ short-term bias, which is even more pronounced in the last years of their sample. “or, to change the metaphor slightly, professional investment may be likened to those newspaper competitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average pref- erences of the competitors as a whole; so that each competitor has to pick, not those faces which he himself finds prettiest, but those which he thinks likeliest to catch the fancy of the other competitors, all of whom are looking at the problem from the same point of view. it is not a case of choosing those which, to the best of one’s judgment, are really the prettiest, nor even those which average opinion genuinely thinks the prettiest. we have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. and there are some, i believe, who practise the fourth, fifth and higher degrees.” (keynes, the general theory of employment, interest and money, ). http://www.oecd.org/daf/fin/financial-markets/ .pdf http://www.oecd.org/daf/fin/financial-markets/ .pdf ( )). furthermore, the anticipation of short-term price movements may induce mar- ket participants to act in a way that amplifies such movements (shin ( )) and may contribute to crashes. we show that the beauty contest analogy for financial markets tells just part of the story because, when liquidity traders’ demand shocks are persistent, prices reflect average expectations not only of the fundamental value but also of liquidity trading. in this paper we present a two-period model of short-term trading with asymmetric information—in the tradition of dynamic noisy rational expectations models (see, e.g., singleton ( ), brown and jennings ( )). we find that if liquidity trading is per- sistent then there is strategic complementarity in the use of private information, and we provide sufficient conditions for that complementarity to generate multiple extremal stable equilibria that can be ranked in terms of price informativeness, liquidity, and volatility. in particular, we find that there are two extremal equilibria: a “high informa- tion” equilibrium (hie) and a “low information” equilibrium (lie). at the hie, prices are good signals of the underlying fundamentals, volatility is low, and liquidity is high; the lie displays the opposite properties in terms of informational efficiency, volatility, and liquidity. in a model identical to ours but with transient liquidity trading, allen, morris, and shin ( ) find that prices (i) are driven by higher-order expectations (hoes) about fundamentals, (ii) underweight private information (with respect to the optimal statisti- cal weight), and (iii) are farther away from fundamentals than investors’ consensus. the same result obtains in our setup when liquidity trading is transient. a similar result also holds at the lie when liquidity trading is persistent. however, at the hie we find that the price is more strongly tied to fundamentals (as compared with investors’ consensus) and overweights average private information (as compared with the optimal statistical weight). therefore, the beauty contest feature of asset prices does not necessarily imply that prices are worse estimators of fundamentals compared to consensus; neither does it imply that prices exhibit inertia or react slowly to changes in the fundamentals. hence we can establish the limits of this beauty contest analogy for financial markets and refute the view that short-term trading always amplifies demand shocks or necessarily leads to uninformative prices or “excess” volatility. we also identify the circumstances in a related paper, we show that a similar conclusion holds in a model with long-term investors (see cespa and vives ( )). part of the debate over the consequences of short-term trading revolves precisely around its al- leged negative effect on the informativeness of asset prices (see, e.g., the “kay review of uk equity markets and long term decision making,” available at http://lawcommission.justice.gov.uk/docs/ http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf under which informed traders stabilize the market by counteracting the actions of liquid- ity traders (at the hie). finally, we deliver sharp predictions on asset pricing that are consistent with the received empirical evidence (including noted anomalies). a crucial hypothesis of our model is that liquidity trading displays persistence. this hypothesis can be viewed as a reduced-form assumption for the performance–flow rela- tionship’s effect on the holdings of mutual funds. coval and stafford ( ) show that mutual funds faced with aggregate redemption orders will curtail their positions and en- gage in “fire sales”. this dynamic generates a temporary and allegedly uninformed price pressure that reduces fund performance. as shown by evidence on the performance–flow relationship (chevalier and ellison ( ), sirri and tufano ( )), poor performance in turn breeds investors’ redemptions, thus engendering further fire sales. the implica- tion is that uninformed orders can display persistence. building on this intuition, lou ( ) tests a capital flow–based explanation for some well-known empirical asset pricing regularities and finds that mutual funds’ shareholdings display strong persistence at a quarterly frequency. campbell and kyle ( ) follow a different approach and disentan- gle the properties of the noise process from the properties of returns; these authors find that liquidity traders’ positions are highly persistent at an annual frequency. in sum, the persistence of liquidity trading appears to be a natural and plausible assumption that is backed by empirical evidence. the mechanism responsible for complementarities is as follows. suppose a risk-averse, short-term trader has a private signal on the firm’s fundamentals. his willingness to spec- ulate on that signal is directly related to how well he can estimate the next period’s price and, significantly, such willingness is also inversely related to the trader’s uncertainty about the liquidation price. indeed, the more volatile the price at which the investor un- winds, the riskier his strategy and the less willing to exploit his private signal the trader becomes. yet an average increased response to private information today, increases the price informativeness and reduces the residual variance of tomorrow’s price conditional on today’s price. this pushes up the response to the private signal today and may induce strategic complementarities in the responses to the private signals. for this to happen the variance reduction effect must be strong enough to overwhelm the usual substitution effect according to which a more informative price today decreases the weight put by the trader on his private signal in the estimation of tomorrow’s price. therefore, a trader’s willingness to act on private information not only depends on his uncertainty about the liquidation price but also affects that uncertainty. we argue that this two-sided loop kay-review-of-equity-markets-final-report.pdf ). http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf 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http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf http://lawcommission.justice.gov.uk/docs/kay-review-of-equity-markets-final-report.pdf may account for the existence of multiple stable equilibria that can be ranked in terms of liquidity, volatility, and informational efficiency. the variance reduction effect is potentially strong when liquidity trading is persis- tent. the crux of our argument revolves around a particular type of inference from the information (as reflected by prices) that arises in this case. if there is persistence then second-period investors can retrospectively assess their first-period inferences about the fundamentals—that is, based on the new evidence gathered in the second period. we therefore term this effect “retrospective inference”. in a market whose investors are both risk averse and asymmetrically informed, it is well-well known that the price impact of trades stems from the sum of an “inventory” component and an “inference” component. in a static market the two terms are positive, but in a dynamic market it is possible for retrospective inference to render the inference component negative. that effect dimin- ishes the price impact of trades, reducing the volatility of the asset price and boosting the response of traders to private information. the intuition is as follows. suppose that second-period informed investors observe a large demand for the asset. if in the first period these investors traded aggressively on their private information, then the first-period price is informative about the fundamentals. therefore, the bulk of the price adjustment to fundamentals must have already occurred in the first period. this reduces the likelihood that demand is being driven by informed trading and thereby makes it more likely that it is driven by liquidity trading. if there is persistence, then this result implies that a high demand for the asset from liquidity traders also affected the first- period aggregate demand —which further implies (for a given price realization) a lower expectation of the fundamentals. so in this case, a large aggregate demand realization leads second-period investors to revise downward their expectation of the liquidation value. this implies in turn that the inference component of the price impact offsets the inventory component, reducing the latter’s significance. the result is diminished first-period investor uncertainty about the unwinding price, which boosts the response of investors to private signals. we have therefore a self-fulfilling loop of strong reaction to first period private signals which leads to a high information equilibrium. the same logic leads to a low information equilibrium when one assumes that first-period investors trade weakly on their private signals. we show that if retrospective inference is present but the variance reduction effect that is, liquidity traders’ position are correlated across trading dates. the former captures the price variation due to the the change in asset exposure that investors experience when clearing the market; the latter captures the price change due to investors’ inferences from aggregate demand for the asset. moderately strong, then two extremal and stable equilibria arise: the lie and the hie. in the hie, volatility is low, liquidity is high, and prices closely reflect the underlying fundamentals; in the lie, volatility is high, liquidity is low, and prices reflect poorly underlying fundamentals. if retrospective inference and the variance reduction effect are very strong then the hie becomes unstable, in which case the only likely equilibrium to arise is the lie. our analysis shows that the strength of the retrospective inference loop depends on traders’ reliance on prices as a source of information for their decisions. suppose, for example, that private signals are much more precise than exogenous public information; then prices are relatively more informative, the loop is very strong, and the hie is unstable. when the public signal precision increases, the retrospective inference loop weakens and thereby stabilizes the hie. finally, when precision of the public signal increases further, the hie disappears, because the variance reduciton effect is weakened, and uniqueness occurs at the lie. thus, our paper shows that public information plays an active role in determining the type of market equilibrium when there is short-term trading. our model predicts that the lie arises under extreme values of public signal precision (which could be proxied by the number of analysts following a given security). the low- information equilibrium is characterized by: (i) a positive inference component of the price impact; (ii) momentum or reversal, depending on the strength of persistence; (iii) high expected returns from providing liquidity; (iv) prices that are far from the semi-strong efficient price; (v) strong short-horizon return predictability from order imbalances; and (vi) low volume accompanied by high levels of disagreement. for intermediate values of public signal precision, the hie can also arise. the high-information equilibrium features (i) a negative inference component of the price impact, (ii) mild momentum, (iii) low expected returns from liquidity provision, (iv) prices that are close to the semi-strong efficient price, (v) weak short-horizon return predictability from order imbalances, and (vi) high volume accompanied by low levels of disagreement. it is important to note that the autocovariance of short-term returns is always positive in the hie but is positive in the lie only when liquidity trading is sufficiently persistent. since the predictability of liquidity trading is an essential ingredient in multiple equilibria, it follows that momentum is a consequence of persistence. that being said, the patterns of prices and price informativeness implied by the two equilibria are markedly different. in particular, momentum along the hie (resp., lie) is a sign that prices are rapidly (resp., slowly) converging toward the full-information value. our model has the following implications: • when high trade volume is associated with informative prices and with low levels of disagreement, then this discriminates in favor of the hie, not only in relation to the lie but also in relation to alternative theories based on differences of opinions (do) models, in which disagreement is associated with high volume. • a negative covariance between conditional volatility of returns and volume does not rule out the applicability of rational expectations models (as suggested by banerjee ( ), for example) since it is consistent with ours. • a negative inference component of the price impact identifies the hie; the ob- servation of a reversal at short horizons identifies the lie (under the maintained hypothesis that our model holds). • if for “fragile” stocks – in the sense of greenwood and thesmar ( ) – there is a low transaction volume when there is high disagreement, then this would be evidence for a lie. similarly, a high transaction volume for non-fragile stocks about which there are low levels of disagreement, constitutes evidence for a hie. the rest of the paper is organized as follows. after discussing the related literature, we analyze the static benchmark. in section iii we study the two-period model, relate it to the beauty contest literature, and present the multiplicity result. we then derive asset pricing implications and use our model to interpret some aspects of the recent financial crisis. the paper’s final section summarizes our results and discusses their empirical implications. most formal proofs are relegated to the paper’s appendix. an online appendix offers a detailed robustness analysis of the model. i related literature our results are related to—and have implications for—three strands of the literature. first, our paper is related to the literature that investigates the relationship between the effect of short-term investment horizons on prices and the reaction of investors to their private signals (see singleton ( ), brown and jennings ( ), froot, scharfstein, and stein ( ), dow and gorton ( ), vives ( ), cespa ( ), vives ( ), and this finding has an empirical counterpart: some spread decomposition models find that, consistently with our hie prediction, the spread’s inference component can be negative. albagli ( )). if prices are semi-strong efficient (as in vives ( )), then traders do not require compensation for increasing their exposure to the asset and so the inventory component of the price impact disappears. as a consequence, the retrospective inference loop breaks down and a unique equilibrium obtains. brown and jennings ( ) analyze a model in which prices are not semi-strong efficient, investors have a short-term horizon, and liquidity trading can be correlated. their work provides a rationale for “techni- cal analysis” that shows how, absent semi-strong efficiency, the sequence of transaction prices is more informative—about the final payoff—than is the current stock price. we argue that, in the absence of semi-strong efficiency, if liquidity trading is correlated then second-period investors can retrospectively evaluate their first-period inferences. this opportunity for reassessment generates strategic complementarities in the use of private information and can also lead to multiple equilibria. other authors find that multiple equilibria can arise in the presence of short-term traders. in this regard, part of the literature assumes an infinite horizon economy. un- der that assumption, multiplicity arises from the bootstrap nature of expectations in the steady-state equilibrium of an overlapping generations (olg) model in which investors live for two periods. spiegel ( ) studies the model with symmetric information. watanabe ( ) extends the model of spiegel ( ) to account for the possibility that investors have heterogeneous short-lived private information. other authors generate multiple equilibria in finite-horizon economies. zhang ( ) shows that short-term trad- ing generates multiple equilibria that can be ranked in terms of price informativeness. however, multiplicity in that paper arises at the information acquisition stage, whereas we find multiplicity in the response to private information. furthermore, public informa- tion in the lie crowds out the production of private information, which is the opposite of what happens in our case. along similar lines, avdis ( ) finds that short-term trading can generate multiple equilibria in information acquisition. finally, chen, huang, and zhang ( ) analyze a model with short-term trading and in which traders receive sig- nals of different precision. these authors show that, even with transient liquidity trading, multiple equilibria can arise in the response to private information. this is so because in the absence of private information, our model is akin to a finite-horizon version of spiegel ( ); hence, in this case we can show that a unique equilibrium obtains. in his case, too, the analysis concentrates on the steady-state equilibrium; his results are therefore not directly comparable to ours. furthermore, information on fundamentals is short lived in watanabe ( ) whereas in our model it is long lived; this difference substantially changes the nature of the inference problem faced by first-period investors. in related research, dennert ( ) concentrates on the steady-state solution in his olg extension of grossman and stiglitz ( ). private information is short lived in this setup also. the uncertainty reduction effect of an increase in the response to private information is boosted by the dispersion of private precisions. the second stream of literature to which our paper relates is the work that addresses the influence of higher-order expectations on asset prices (see allen, morris, and shin ( ), nimark ( ), bacchetta and van wincoop ( ), kondor ( )). bacchetta and van wincoop ( ) study the role of hoes in the foreign exchange market. they show that such expectations worsen the signal extraction problem that investors face when observing exchange rate fluctuations that originate from trades based on hedging motives and fundamentals information. in our setup this deterioration occurs at the lie; at the hie, in contrast, investors’ strong reaction to private information makes signal extraction less of a problem. it is noteworthy also that, in contrast with do models (see, e.g., kandel and pearson ( ), banerjee ( ), kondor ( )), we find that at the hie, in which there is low disagreement, volume is large and the conditional volatility of returns is negatively related to expected volume. finally, this paper is related to the literature on limits to arbitrage. in that regard, our multiplicity result is reminiscent of de long et al. ( ), but in a model with rational traders and a finite horizon. thus, our paper naturally relates to the strand of this literature that views limits to arbitrage as the analysis of how “non-fundamental demand shocks” impact asset prices in models with rational agents (gromb and vayanos ( ), vayanos and woolley ( )), emphasizing the role of liquidity shocks persistence. our model also predicts that momentum is related to a high volume of informational trading, which is in line with the evidence presented in llorente et al. ( ). some have claimed that limits to arbitrage capital are responsible for crashes and meltdowns (see duffie ( ); see also khandani and lo ( ) for the august quant meltdown). in our model, meltdowns can be explained in terms of a transition from the high- to the low-information equilibrium. ii the static benchmark consider a one-period stock market in which a single risky asset (of liquidation value v) and a riskless asset (of unitary return) are traded by a continuum of risk-averse, informed investors in the interval [ , ] and also by liquidity traders. we assume that v ∼ n(v̄,τ− v ). investors have constant absolute risk aversion (cara) preferences (we use γ to denote in a static trading model, ganguli and yang ( ) discusses complementarities in information acquisition. the risk-tolerance coefficient) and maximize the expected utility of their wealth: wi = (v−p)xi. before the market opens, each informed investor i obtains private information on v, receiving a signal si = v + εi, εi ∼ n( ,τ− ε ), and submits a demand schedule (generalized limit order) x(si,p) to the market; indicating the investor’s desired position in the risky asset for each realization of the equilibrium price. assume that v and εi are independent for all i and that error terms are also independent across investors. liquidity traders submit a random market order u (independent of all other random variables in the model), where u ∼ n( ,τ− u ). finally, we adopt the convention that the average signal∫ si di is equal to v almost surely. in other words, errors cancel out in the aggregate:∫ εi di = . in the cara-normal framework just described, a symmetric rational expectations equilibrium (ree) is a set of trades contingent on the information that investors have, {x(si,p) for i ∈ [ , ]}, and on a price functional p(v,u) (measurable in (v,u)) such that investors in [ , ] optimize (given their information) and the market clears: ∫ xi di + u = . given this definition, it is easy to verify that a unique and symmetric equilibrium in linear strategies exists in the class of equilibria with a price functional of the form p(v,u) (see, e.g., admati ( ), vives ( )). the equilibrium strategy of cara investor i is given by x(si,p) = γ e[v|si,p] −p var[v|si,p] . letting τi ≡ (var[v|si,p])− and denoting by αe = τε/τi the optimal statistical (bayesian) weight given to private information in e[v|si,p], we have that γτi = (a/αe), where a = γτε, ( ) denotes the responsiveness to private information of investor i. note that a is independent of the variance of the price or of liquidity trading. this is because var[v|si,p] cancels in the numerator and denominator of x(si,p). if market clearing is imposed then the we assume without loss of generality that, with cara preferences, the nonrandom endowment of informed investors is zero. the unique equilibrium in linear strategies of this model is symmetric. this convention is justified in section . of the technical appendix to vives ( ). equilibrium price is given by p = ∫ ei[v] di + αe a u ( ) = e[v|p] + Λe[u|p], ( ) where e[u|p] = a(v −e[v|p]) + u and Λ = vari[v] γ . ( ) equations ( ) and ( ) show that the price can be represented in two different ways. ac- cording to the representation in ( ), the price reflects not only the consensus opinion that investors hold about the liquidation value but also the effect of demand from liquid- ity traders (multiplied by their risk tolerance–weighted uncertainty over the liquidation value). indeed, owing to cara and normality, in a static market an investor’s demand is proportional to the expected gains from trade, e[v|si,p]−p. because the price aggregates the demand of all investors, it reflects the consensus opinion ∫ ei[v] di that is shocked by the orders of liquidity traders. according to ( ), the equilibrium price reflects investors’ estimates of the fundamen- tals v (the so-called semi-strong efficient price e[v|p]) and of liquidity traders’ demand u; risk-averse investors demand compensation for accommodating liquidity traders’ orders. under asymmetric information, that demand is not perfectly observable from the price. therefore, such compensation is increasing in an investor’s estimate e[u|p] scaled by Λ. it follows from ( ) that, for a given e[u|p], greater investor uncertainty about the liquidation value or about the risk involved is associated with higher Λ and greater compensation. thus Λ captures the “inventory” component of market liquidity. liquidity traders’ orders have an additional effect on the price through their impact on the semi-strong effi- cient price e[v|p]. this effect induces an inference component that adds to the inventory component, implying that the (reciprocal of) market liquidity can be written as λ ≡ ∂p ∂u = Λ + ( −αe) aτu τ , when risk-averse investors accommodate an expectedly positive demand of liquidity traders, the former require compensation for risking that the liquidation value ends up being higher than the public expectation (conversely, if e[u|p] < then investors insist on a price that is lower than e[v|p]—to cover the risk that v < e[v|p]). such compensation is increasing in the uncertainty faced by investors (as captured by Λ) and in the the extent of their anticipated exposure to the liquidity traders’ shock (i.e., their expected inventory e[u|p]). where τ = /var[v|p] = τv + a τu. we remark that, all else equal, in a static setup the inference component magnifies the price impact of liquidity traders’ orders. iii a two-period market with short-term investors consider now a two-period extension of the market analyzed in the previous section. at date (resp., ), a continuum of short-term investors in the interval [ , ] enters the market, loads a position in the risky asset, and then unwinds that position in period (resp., ). investor i has cara preferences (we denote by γ the coefficient for common risk tolerance) and maximizes the expected utility of her short-term profit πin = (pn+ − pn)xin for n = , with p = v̄ and p = v. the short-term horizons of investors can be justified on the grounds of incentive reasons related to performance evaluation or of the difficulties associated with financing long-term investment when there are capital market imperfections (see holmström and ricart i costa ( ) and shleifer and vishny ( )). an investor i who enters the market in period receives a signal si = v+εi that she recalls in the second period, where εi ∼ n( ,τ− ε ) and where v and εi are independent for all i. we assume further that in the second period a signal sp = v+η is publicly disclosed to the market, where η ∼ n( ,τ− η ) is independent of both v and εi for all i. the public signal introduces an additional source of public information on the fundamentals (i.e., besides the equilibrium prices) whose informativeness is exogenous to the trading process. the real-world counterpart of this assumption is any public announcement about the asset’s value (e.g., an earnings announcement, analysts’ consensus forecast of earnings). once again we adopt the convention that, given v, the average private signal ∫ si di equals v almost surely and so errors cancel out in the aggregate: ∫ εi di = . we restrict our attention to equilibria in linear demand functions. we denote by x (si,p ) = a si − ϕ (p ) and x (si,sp ,p ,p ) = a si + bsp − ϕ (p ,p ) an investor’s desired position in the risky asset for each realization of the equilibrium price at (respec- tively) dates and . the constants an and b denote, respectively, the weight an investor gives to private information at date n and the weight she gives to the public signal. the function ϕn(·) is a linear function of the equilibrium prices. the adverse selection effect is a consequence of the signal extraction problem that dealers face in this market: since a > , if investors on average have good news then they buy the asset and so e[v|p] increases, reflecting that information. however, this effect cannot be distinguished from the buying pressure of liquidity traders, which also has the effect of increasing e[v|p]. as before, we assume (w.l.o.g.) that the nonrandom endowment of investors is zero. the equilibria in linear strategies of this model are symmetric. the position of liquidity traders is assumed to follow a first-order autogressive or ar( ) process: θ = u , θ = βθ + u ; ( ) here β ∈ [ , ] and {u ,u } is an independent and identically distributed (i.i.d.) random process (independent of all other random variables in the model) with un ∼ n( ,τ− u ). other authors have adopted this assumption for liquidity traders, including singleton ( ), campbell and kyle ( ), he and wang ( ), biais, bossaerts, and spatt ( ), and cespa and vives ( ). if β = , then {θ ,θ } follows a random walk and we are in the usual case of independent liquidity trade increments: u = θ − θ is independent of u (kyle ( ), vives ( )). if β = , then liquidity trading is i.i.d. across periods; this is the case considered by allen, morris, and shin ( ). persistent liquidity trading is taken as a primitive of the model, but such trading can be shown to arise endogenously in a model where liquidity traders are replaced by rational hedgers with different investment horizons (see cespa and vives ( )). persistence in liquidity trading can be given several possible interpretations, depend- ing on the frequency of observations. at a daily or intra-daily frequency, to assume persis- tence is a simple way to capture the need of liquidity traders to break down a large order into a series of smaller orders and thereby minimize price impact; as such, this assumption is consistent with several empirical findings (e.g., griffin, harris, and topaloglu ( ), chordia and subrahmanyam ( )). at a lower frequency, liquidity trading persistence can be seen as a reduced-form assumption capturing the performance–flow relationship’s effect on the holdings of mutual funds. coval and stafford ( ) show that mutual funds faced with aggregate redemption orders engage in fire sales (resp., purchases), creating more specifically, suppose that we replace the first-period liquidity traders with a set of hedgers in the interval [ , ] and that each of these hedgers receives an idiosyncratic and normally distributed endowment shock θi that is independent of the model’s other random variables. all hedgers take a position in the asset at date . however, a fraction β of them (denoted hl) have a long-term horizon and hold their positions until the liquidation date; the complementary fraction (denoted hs) has a short- term horizon, and these hedgers liquidate their positions at date . under this model we can show that, in a linear equilibrium, the persistence coefficient corresponds to the β-weighted relative responsiveness to the endowment shock displayed by hl (i.e., as compared with the average response of both hl and hs). since the responsiveness of hedgers is endogenous and since information is asymmetric, it follows that that in this case a participation externality (similar to the one in admati and pfleiderer ( ), pagano ( ), and dow ( )) arises. namely, hedgers’ decisions to trade in the first period depend on market liquidity, which in turn depends on hedgers’ decisions to trade. this new loop can generate multiplicity with different levels of hedging activity. contemporaneous, uninformed, and temporary negative (resp., positive) price pressure. coupling this result with the evidence that capital flows in and out of mutual funds are strongly related to past performance (chevalier and ellison ( ), sirri and tufano ( )), negative shocks to the capital of mutual funds can affect those funds’ trades and thus have a negative (resp., positive) effect on their performance through feeding back to the funds’ capital outflows (resp., inflows). empirical evidence of liquidity trading persistence has been obtained in two ways. campbell and kyle ( ) disentangle the properties of the noise process from the prop- erties of returns. these authors examine annual aggregate returns of index data in the united states and then attempt to fit the properties of the time series with different mod- els that feature noise. they find that, at a yearly level, noise traders’ positions are highly persistent (from % to % of the noise remains after one year). an alternative strategy is to look at the f filings of mutual funds that face negative or positive net inflows and are thus led to trade for non-informational purposes (coval and stafford ( )). this is the approach taken by lou ( ), who finds that mutual funds’ shareholdings display strong persistence at a quarterly frequency. we denote by ei [y ] = e[y |si,p ] and vari [y ] = var[y |si,p ] the expectation and variance of the random variable y formed by a date- investor using private and public information; e [y ] = e[y |p ] and var [y ] = var[y |p ] denote the same case but when only public information is used. similar definitions for date- investors yield ei [y ] = e[y |si,sp ,p ,p ] and vari [y ] = var[y |si,sp ,p ,p ] as well as e [y ] = e[y |sp ,p ,p ] and var [y ] = var[y |sp ,p ,p ]. the variables τn and τin denote the precision of investor forecasts of v based (respectively) only on public information and on both public and private information; thus, τn = ( /varn[v]) and τin = ( /varin[v]). letting αen = τε/τin, we have ein[v] = αensin + ( −αen )en[v]. we now derive the informational content of prices in a linear equilibrium. consider a candidate linear (symmetric) equilibrium where xi = a si−ϕ (p ) and xi = a si +bsp − ϕ (p ,p ) for ϕn(·) a linear function. denote by z ≡ a v + θ the noisy informational addition about v generated by informed investors in period (i.e., the “informational content” of the first-period order flow). similarly, put ∆a ≡ a − βa and denote investors’ second-period informational addition by z ≡ ∆a v + u . we now show that, at a linear equilibrium, p is observationally equivalent (o.e.) to z and that, given sp , the coval and stafford argue in more detail that fire sales occur in mutual funds that follow specialized investment strategies and that exhibit considerable overlap in their holdings. easley, hvidkjaer, and o’hara ( ) develop a methodology to estimate the probability of informed trading from transaction data. sequence {z ,z } is o.e. to {p ,p }. if we let xn ≡ ∫ xin di and impose market clearing in the first period, then (by our convention) the implication is that x + θ = ⇐⇒ a v + θ = ϕ (p ). ( ) in the second period, the market-clearing condition is x + βθ + u = ⇐⇒ x −βx + u = ⇐⇒ a v + bsp −ϕ (p ,p ) −β(a v −ϕ (p )) + u = ⇐⇒ ∆a v + u = ϕ (p ,p ) −βϕ (p ) − bsp ; ( ) in the second line we have used ( ), and by ∆a = a − βa we denote the β-weighted net trading intensity of second-period informed investors. from ( ) and ( ) it is easy to see that z is o.e. to p and that, given sp , {z ,z } is o.e. to {p ,p }. hence e [v] = τ− (τvv̄+a τuz ), e [v] = τ − (τ e [v] +τηsp + ∆a τuz ), var [v] ≡ τ − = (τv +a τu) − , var [v] ≡ τ− = (τ + τη + (∆a ) τu) − , ein[v] = τ − in (τnen[v] + τεsi), and varin[v] ≡ τ− in = (τn + τε) − . we shall now relate price formation to the keynes’s notion of a beauty contest. then we look at the retrospective inference mechanism that we associate with persistent liquidity trading and characterize equilibria, their stability properties, and trading strate- gies. in this way we demonstrate the limits of the beauty contest analogy for financial markets. we end section iii with a robustness analysis. a prices and beauty contests here we give an expression for the equilibrium price that highlights the dependence of that price on investors’ higher-order expectations about fundamentals (cf. allen, morris, and shin ( )). when there is persistence, liquidity traders’ orders at time n also affect the demand for the asset at time n+ . so in a two-period model, first-period investors use their private information also to infer the demand of liquidity traders from the first-period price. as a result, the latter is driven by investors’ hoes about fundamentals and by their average expectations about liquidity trading. this result, in turn, has implications for the informational properties of the price. let us denote by ēn[v] ≡ ∫ ein[v] di the consensus opinion about the fundamentals at time n, where ēn[v] = αenv + ( − αen )en[v]. starting from the second period, if we impose market clearing then ∫ x (si,sp ,p ,p ) di + θ = . because of cara and normality, we have x (si,sp ,p ,p ) = γvari [v] − (ei [v] − p ). substituting this expression into the market-clearing equation and solving for the equilibrium price now yields p = ē [v] + vari [v] γ θ . ( ) similarly, imposing market clearing in the first period we have ∫ x (si,p ) di + θ = ; solving for the equilibrium price then yields p = ē [p ] + vari [p ] γ θ . ( ) substituting ( ) and then rearranging, we obtain p = ē [ ē [v] + vari [v] γ θ ] + vari [p ] γ θ = ē [ē [v]] + β vari [v] γ ē [θ ] + vari [p ] γ θ . ( ) according to ( ), three terms constitute the first-period price: investors’ second-order average expectations over the liquidation value (ē [ē [v]]), the risk-adjusted effect of the first-period stock of liquidity trades (θ ), and investors’ average expectations over first- period liquidity trades (ē [θ ]). those latter expectations arise because p depends on θ , which in turn is correlated with θ when β > . thus, investors in period are also interested in estimating θ . expression ( ) implies that, because of persistence in liquidity trading, the weight of the price on investors’ average information is the sum of two terms. the first term captures the effect of hoes on v, and the second reflects the effect of investors’ average expectations concerning θ . we have that ē [ē [v]] = ᾱe v + ( − ᾱe )e [v]; ē [θ ] = a ( −αe )(v −e [v]) + θ . here ᾱe = αe ( − (τ /τ )( − αe )), and a denotes first-period investors’ average responsiveness to private information. so given ( ), the implication is that the total when computing ē [θ ] we have z = ei [z ] = a ei [v] + ei [θ ], and ei [θ ] = z − a ei [v] = a (v −ei [v]) + θ . computing average expectations yields ē [θ ] = a (v − ē [v]) + θ . finally, using ē [v] = αe v + ( −αe )e [v] yields the expression in the centered formula above. weight of the price on average private information is given by αp = ᾱe + β vari [v] γ a ( −αe ). ( ) observe that ᾱe < αe for any β. therefore, if liquidity trading is transient (β = ) then the first-period price places more weight on public information than does the optimal statistical weight. this finding is in line with allen, morris, and shin ( ), who prove that if information is heterogeneous then prices reflect investors’ hoes about the final payoff. in this case, the law of iterated expectations does not hold and investors’ forecasts overweight public information (in the sense that αp = ᾱe < αe ). the reason is that investors anticipate the average market opinion while knowing that this opinion depends also on the public information observed by other investors. in section iii.e we show that the price is then systematically farther away (than the consensus) from fundamentals. if liquidity trading is persistent, however, then p also reflects investors’ average expectations about θ . hence another term is added to ᾱe in the expression for αp given by ( ). we argue in section iii.e that this additional term can reverse the conclusion we derived under transient liquidity trading. b retrospective inference and equilibrium prices we start by giving a general description of the equilibrium price function providing three equivalent expressions for prices that highlight different properties of the model. proposition . at a linear equilibrium, the price is given by pn = αpn ( v + θn an ) + ( −αpn )en[v], ( ) where θn = un + βθn− and where an and αpn denote the responsiveness to private in- formation exhibited at period n by investors and by the price, respectively (see equations (a. a), (a. b), (a. ), and (a. )). we have that αp = αe < . according to ( ), at period n the equilibrium price is a weighted average of the market expectation about the fundamentals v (the semi-strong efficient price) and a noisy market signal about v that depends on the response to private information. rearranging this expression yields pn −en[v] = αpn an (an(v −en[v]) + θn) = Λnen[θn] ( ) for Λn ≡ αpn/an, which implies that there is a discrepancy between pn and en[v]. as in the static market (see ( )), this discrepancy reflects a premium that is proportional to the expected stock of liquidity trading that investors accommodate at n. the result is our second equilibrium price expression as follows. corollary . at a linear equilibrium, the price incorporates a premium above the semi- strong efficient price: pn = en[v] + Λnen[θn], ( ) where Λ = vari [v]/γ and Λ = vari [p ] γ + βΛ . ( ) a comparison of ( ) with ( ) reveals that short-term trading affects the inventory component of liquidity. in a static market, investors who absorb the demand of liquidity traders are exposed to risk stemming from the randomness of v. in a dynamic market, however, short-term investors at date face the risk due to the randomness of the next- period price (i.e., the price at which they unwind). to the extent that liquidity trading displays persistence, informed second-period investors absorb part of the first-period liq- uidity traders’ positions; this dynamic contributes to first-period investors’ uncertainty about p , yielding ( ). we can use ( ) to show that, as in the static benchmark, under asymmetric informa- tion the price is affected not only by the inventory component Λn but also by an inference component. this claim is formalized in our next corollary. corollary . let a = . at a linear equilibrium, p = λ z + ( −λ a )v̄ and ( a) p = λ z + τη τi sp + γτ e [v] + βz γτi . ( b) here λn denotes the price impact of trades in period n = , : λn ≡ ∂pn ∂un = αpn an + ( −αpn ) ∆anτu τn . ( ) according to ( ), the inference component of liquidity at n = is captured by ( −αp ) ∆a τu τ . ( ) as shown in ( ), a dynamic market differs from the static benchmark in that the sign of this component depends on the β-weighted net position of informed investors; thus the net trading intensity ∆a = a −βa . as a result, the effect of private information in the second period depends on the change in informed investors’ positions, where this change is measured by ∆a = a −βa . the implication is that the sign of the inference component depends on the magnitude of a as compared with a /β. therefore, the first- period response to private information affects the informational innovation extracted from p and also (when β > ) the one extracted from p —that is, both z and z —as well as the sign of the inference component in λ . when β > the door is open to a negative inference component in the second period when a is large since in this period investors retrospectively reassess the first period inference about the fundamentals based on the new evidence gathered. suppose that second-period informed investors observe high demand for the asset (i.e., z high). if a is large then the first-period price is quite informative about v (since z = a v + θ ). hence (i) most of the price adjustment to fundamentals information must have occurred in the first period and (ii) demand is likely to be driven by liquidity trading. since β > , it follows that high demand for the asset from liquidity traders also affected the first-period aggregate demand. but for a given price realization p , that would imply a lower expectation of the fundamentals. indeed, if a is so large that ∆a < , then a large aggregate demand realization leads second-period investors to revise downward their expectations of the liquidation value because a large z = ∆a v + u is bad news about v when ∆a < . in this case the inference component in λ is negative and offsets the inventory component. if instead a is small, the first period price is poorly informative about v, and a second period large realization z is more likely to come from informed investors. for β > this reinforces the belief that low liquidity traders’ demand affected the first period demand for the asset and, for a given price realization p , implies a higher expectation of the fundamentals (since ∆a > ). in this case, the inference component is positive and adds to the inventory component, increasing λ . we have that αp = αe and so −αp ∈ ( , ). this is because, for given p and z = a v + θ , a higher value for θ provides stronger evidence that the fundamentals v is low. in summary, when liquidity trading displays persistence, second period investors can retrospectively reassess the first period inference about the fundamentals, based on the new evidence gathered in the second period, affecting the inference component of second period price impact of trade (λ ). we thus term this effect “retrospective inference”. c equilibrium characterization short horizons create a dependence of a on the residual variance of p given p , generating an uncertainty reduction effect when a increases. the reason is that short-term investors in the first period trade according to x (si,p ) = γ ei [p ] −p vari [p ] =⇒ a = γ weight to si in ei [p ] vari [p ] . ( ) by this implication, a is directly related to the relevance of the private signal to forecast p and inversely related to investors’ uncertainty about p . two effects are present that, contrary to the static case, do not cancel each other. on the one hand, we have the usual substitution effect whereby a higher on average a leads to a more informative price in period (higher τ and τi ), and therefore a lower weight to private information τ�/τi in ei [p ], which tends to depress a . on the other hand, a higher average a and larger τ leads to a lower vari [p ], which tends to raise a . this is a source of strategic complementary in the responses to private information. with short-horizons, this uncertainty reduction effect also works through λ . this is because, first period investors are interested in forecasting p and, for any public signal, the extent to which p differs from p depends on λ (see ( b)). therefore, a higher λ (in absolute value) will, ceteris paribus, increase first-period investors’ uncertainty about p and depress a . recall that when β > it is possible that ∆a < when a is high enough, implying that the inference component in λ offsets the inventory component. in this case, the second- period price impact of trade is small, which diminishes first-period investors’ uncertainty about p and so boosts their response to private signals. hence, the variance reduction (second) effect dominates the substitution (first) effect and a high level of a can be sustained in equilibrium. at the same time, a lower level of a is also self-fulfilling. indeed, a low a generates a low τ and a high residual variance for p given p which makes the low a self-fulfilling. in this case we have ∆a > (even if β > ) and the retrospective inference plays an anlaogous role as the “adverse fundamental” effect in goldstein and yang ( ). second period price impact of trade (λ ) is high, augmenting the residual variance of p . summarizing, investors’ willingness to speculate on private information not only de- pends on their uncertainty about the liquidation price, but also affects that uncertainty. this two-sided loop in the determination of a gives rise to strategic complementarities in the use of private information, which can yield multiple equilibria. the following proposition characterizes linear equilibria and provides suffcient conditions for multiple equilibria to exist. those conditions imply that the variance reduction effect is strong enough. proposition . suppose τη > . • if β > / , γ τετu > ( β − )/( − β), and τη ≤ τ̂η (for some τ̂η > defined in the appendix, see (a. c)), there always exist at least three linear equilibria where a = γτε and a ∈{a∗ ,a∗∗ ,a∗∗∗ }, with a∗ ∈ ( ,a ), a∗∗ ∈ ( + γτua γβτu , + γτua γβτu ) , a∗∗∗ > + γτua γβτu , implying a∗ < a < a ∗∗ < a ∗∗∗ . when a =   a ∗ , then a −βa∗ > , and λ ∗ > , a∗∗ ,a ∗∗∗ , then a −βa∗∗ < , and λ ∗∗ < . ( ) along these equilibria: τ∗n < τ ∗∗ n < τ ∗∗∗ n , n = , . ( ) • if β = , there exists a unique equilibrium with a = γτε, γ a τu(a τu + τε + τη) + γ τu(a τu + τε + τη) < a∗ < a , and λ∗ > . according to this proposition, multiplicity requires that private information be strongly reflected in prices (γ τετu > is sufficient), persistence (β) is high, and public precision (τη) is low. all of these conditions strengthen the retrospective inference and the de- scribed uncertainty reduction effect loop. a contrario, for example, a higher precision of the public signal makes p more dependent of sp and less on p and therefore the impact of τ on the residual variance of p is lessened. a Ψ�a � lie hie iie figure : the best-response mapping ( ) for β = , γ = / , τu = τv = , τη = , and τε = . . in view of ( ), we refer to the three equilibria described in proposition as (respec- tively) the low-, intermediate-, and high-information equilibrium: lie, iie, and hie. in the appendix we show that first-period equilibrium responsiveness is obtained as a fixed point of the following function: ψ(a ) = γ (λ ∆a + τη/τi )αe (λ ∆a + τη/τi ) /τi + λ /τu + τη/τ i . ( ) numerical analysis shows that this function crosses the -degree line at most three times, which suggests that the three equilibria described in proposition are the only ones that can arise (see figure ). our numerical results show further that these equilibria can be ranked in terms of second-period price impact (λ ), inventory component of liquidity (Λn), and conditional volatility (var [p ]). the following result gives more details. numerical result . when multiple equilibria arise, these inequalities hold: λ∗ > |λ ∗∗ | > |λ ∗∗∗ |; ( a) Λ∗n > Λ ∗∗ n > Λ ∗∗∗ n ; ( b) var [p ] ∗ > var [p ] ∗∗ > var [p ] ∗∗∗. ( c) along the hie, ∆a < and the inference component of liquidity is negative. this finding is consistent with second-period traders revising downward their first-period as- sessment of the payoff in the presence of a positive demand shock (i.e., engaging in retrospective inference). this result is consistent also with the findings of some spread decomposition models (e.g., huang and stoll ( ), van ness, van ness, and warr ( ), henker and wang ( )) in which the adverse selection component of the spread can be negative. thus, our model provides a theoretical justification for this empirical finding. in figure we display the effects of a change in the values of public and private signal precision, persistence, and liquidity traders’ demand precision on the best response ( ). as the graphs show, uniqueness always occurs at the lie and requires high public pre- cision or low private precision, persistence, or liquidity traders’ precision. intuitively, in all of these cases the endogenous public signal (the price) becomes relatively less in- formative than the exogenous public signal (sp ), leading second-period investors to rely less on price information. this dynamic weakens strategic complementarity by softening the self-reinforcing uncertainty reduction loop resulting from retrospective inference and thereby yields a unique equilibrium. it is worth noting that it can be checked that the best response ψ(·) is downward sloping when β = . in figure we show that the effect of an increase in public signal precision on a depends on the equilibrium that arises. along the hie (resp., lie), a larger τη leads to a decrease (resp., increase) in a . the reason for this result is that a more precise public signal reduces traders’ reliance on price information when forecasting the fundamentals. thus, along both equilibria, the effect of retrospective inference is weaker in the second period. in the hie (lie) this weakened effect increases (decreases) first-period investors’ uncertainty about p , leading to a decrease (increase) in a . it is worth noting that huang and stoll ( ) assumes uninformed market orders to be generated by an ar( ) process, and the estimated parameter of that process turns out to be positive and close to. negative inference components also occur in different spread decomposition models. for example, hamm ( ) investigates the effect of exchange-traded funds on the liquidity of underlying stocks and estimates a spread decomposition model based on madhavan, richardson, and roomans ( ). in several of her findings, the inference component of the spread is negative—leading to the exclusion of such “out-of-range” observations. see also foucault, pagano, and röell ( ), ch. . . . public precision has little effect on the equilibrium ex ante, while the degree of risk tolerance has an effect similar to that of private precision. along the hie, second-period investors facing a large positive demand for the asset will adjust their estimate of the fundamentals downward, which implies that the inference component of λ is negative. other things equal, a more precise public signal reduces the absolute value of the inference component, which works to increase first-period investors’ uncertainty about p . in the lie, the converse statement holds. a Ψha l ΤΗ = ΤΗ = (a) a Ψha l ΤΕ = ΤΕ = . (b) a Ψha l Β=. Β= (c) a Ψha l Τu = . Τu = (d) figure : comparative statics. we plot the best response ( ) for the parameters’ value of figure (in orange) and show the effect of a change in the values of τη, τε, β, and τu (dashed, blue curve). in panel (a) we increase public signal precision to τη = ; in panel (b) we decrease private signal precision to τε = ; in panel (c) we decrease liquidity traders’ persistence to β = . , and in panel (d) we decrease the precision of liquidity traders’ demand to τu = . . if the public signal is totally uninformative then, for β > , the retrospective inference and variance reduction loop becomes extremely strong. in this case, the best response ( ) becomes discontinuous at the iie (which therefore disappears; see figure ) and so we always obtain two equilibria that can be computed in closed form. this claim is formalized in our next corollary. corollary . suppose τη = . • if β > then there always exist two linear equilibria, where a = γτε and a ∈ a Ψha l ΤΗ = ΤΗ = ΤΗ = � ΤΗ = � ΤΗ = figure : the best-response mapping ( ) when the public signal’s precision ranges within the set { , / , / , , }. the other parameter values are β = , γ = / , τu = τv = , τε = . , and τη = . when τη = , note that ψ(·,τη) diverges at the point â ≡ ( +γτua )/(γβτu) and the iie disappears. for τη > , we have ψ(â , . ) = . , ψ(â , . ) = . , ψ(â , ) = . , and ψ(â , ) = . . {a∗ ,a∗∗∗ } for a∗ < a < a∗∗∗ (see (a. ) and (a. ) for explicit expressions). if a =  a ∗ then a −βa∗ > and λ ∗ > (lie), a∗∗∗ then a −βa∗∗∗ < and λ ∗∗∗ < (hie). furthermore, |λ∗∗∗ | < λ ∗ , Λ ∗∗∗ n < Λ ∗ n, prices are more informative, and var [p ] is lower along the hie. • if β = , then there exists a unique equilibrium with a = γτε and a∗ = γa τu + γa τu < a . remark . it is possible to show (as in vives ( )) that a unique equilibrium arises when prices are set by a sector of competitive and risk-neutral market makers. in this case the market makers do not require compensation (for inventory risk) in order to clear the market, and prices are semi-strong efficient. the uncertainty reduction effect of an increase in a is present when β > but weakened, which ensures uniqueness. it is also possible to show that the equilibrium is unique when investors have no private information (τε = ). in this case our model is akin to grossman and miller ( ) and investors trade only to accommodate liquidity traders’ orders. prices are therefore invertible in the latter’s demand and retrospective inference does not arise, with price informativeness depending only on prior precsion. remark . we can draw a parallel between our model and models in which investor actions have a feedback effect on the asset’s value. in papers that feature such models (e.g., ozdenoren and yuan ( ), bond, goldstein, and prescott ( ), dow, goldstein, and guembel ( ), goldstein, ozdenoren, and yuan ( )), complementarities-driven multiplicity of equilibria arises also from the effect of the price on the asset’s value. in our paper, the price at n = (i.e., p ) represents the asset’s value from the perspective of investors at n = , and their trading also affects p . this dynamic corresponds to the feedback effect from prices to values in a one-period feedback model. bond, goldstein, and prescott ( ) show that, if agents use market prices when deciding on corrective actions (as when the board considers firing the ceo in response to a low stock price), then prices adjust to reflect this use and may thus become less revealing. in ozdenoren and yuan ( ), prices are informative about both the fundamentals and the likelihood of coordination among informed investors. multiple equilibria arise when the price is more informative of the coordination motive than of the fundamentals. in their paper, the feedback effect’s strength depends on the sensitivity of asset value to investment in the risky asset. the parallel in our model is the degree of persistence in liquidity trading. in both models, multiplicity tends to arise when the feedback effect is strong. much as in our model, in ozdenoren and yuan ( ) there are multiple equilibria also when the precision of private information is high and base liquidity trading low. yet unlike their study, in which an increase in public precision leads to a higher coordination motive and multiple equilibria, our model (with no coordination motive) yields the opposite result. d stability in this section we use the best response ( ) to perform a stability analysis of the equi- libria. toward that end, consider the following argument. assume that the market is at an equilibrium point ā and so ā = ψ(ā ). suppose now that a small perturbation to ā it is easy to see that in equilibrium a = γ/ ( τ− � + τ − ) and therefore we have always that ∆a > and λ = τu∆a /τ > . occurs. as a consequence, first-period investors modify the weight they give to private information; then the aggregate weight becomes ā′ = ψ(ā ′ ). if the market returns to the original ā then—according to the best-reply dynamics with the best-response function ψ(·)—the equilibrium is stable; otherwise, it is unstable. hence we can say that, in a stable (unstable) equilibrium, if investors other than i put a lower weight on their signals then (i) the price is noisier and (ii) investor i reacts by increasing less (more) than propor- tionally the weight on his own signal and so contributing less (more) than proportionally to restoring price informativeness. formally, we have the following definition. definition (stability). an equilibrium is stable (unstable) if and only if its correspond- ing value for a is a stable (unstable) fixed point for the best-response function ψ(·)—that is, iff its corresponding value for a satisfies the inequality |ψ′(a )| < . for τη > , if multiple equilbria arise then the iie is always unstable. on the contrary, in our simulations the lie is always stable. finally, the behavior of the hie is more complex. in particular, for the hie to be stable we require that private signals not be “too” precise when compared with the public signal. in the extreme case when τη = , we can formally analyze the best-response mapping and obtain the following result. corollary . suppose τη = . then (i) ψ ′(a ) < and (ii) the lie (resp., hie) is stable (resp., unstable) with respect to the best-response dynamics: |ψ′(a∗∗∗ )| > > |ψ ′(a∗ )| . ( ) intuitively, if private information is much more precise than public information then the retrospective inference and the variance reduction loop become very strong. in that case we approach a situation close to that described in corollary , which makes the hie always unstable. in figure we set β = , γ = / , and τu = τv = ; we also partition the parameter space {τε × τη | τη ∈{ , . , . . . , }, τε ∈{. , . , . . . , }} into five regions depending on whether multiple equilibria or instead a unique equilibrium obtains, whether the hie is stable, and whether responses to private information are strategic substitutes or strategic complements. this claim follows immediately from the inequality ψ( ) > ; hence the best-response mapping cuts the -degree line from below at the iie, which implies that ψ′(a∗∗ ) > . as shown in figure , the responses of traders to private information in the hie and the lie are strategic complements or substitutes depending on the parameters. for given τε, the higher is τη figure : the equilibrium set for β = , γ = / , τu = τv = , τη ∈{ , . , . . . , }, and τε ∈ {. , . , . . . , }. the black line denotes the set τη = τε. for values of (τε,β) in the white and yellow regions, the equilibrium is unique, whereas multiple equilibria (me) obtain when (τε,β) are in the other regions, where the hie can be stable or unstable depending on the difference between τη and τε. remark . what is the effect of a shock to parameter values on the market’s equilib- rium? the answer to this question depends on whether or not the hie is stable (see the online appendix). when the hie is stable we can easily generate non-monotonic effects of exogenous parameter changes (e.g., in private signal precision or in risk toler- ance) on the response to private information, the conditional volatility of returns, and the informational efficiency of prices. these results are possible because a parameter change may induce traders to coordinate at a different equilibrium. for instance, it is possible that a large decrease in private signal precision produces an increase in the equilibrium response to private information and informational efficiency—as well as a decline in the conditional volatility of returns, with the equilibrium shifting from the initial lie to the hie. when the hie is unstable, numerical simulations show that the effect of even a mild shock to parameter values depends on how persistent is the demand of liquidity traders. when β ∈ ( , ), the equilibrium converges to the lie; when β = , the market oscillates between two nonequilibrium values. the more likely it will be for at least one of the two equilibria to display strategic complementarities. for instance, when β = , γ = / , τu = τv = , τε = , and τη = . we obtain (a ∗ ,a ∗∗∗ ) = ( . , . ) and (ψ′(a∗ ),ψ ′(a∗∗∗ )) = (− . ,− . ). increasing τη to yields (a∗ ,a∗∗∗ ) = ( . , . ) and (ψ′(a∗ ),ψ ′(a∗∗∗ )) = (− . , . ). finally, if we further increase τη to (resp., to ), then the hie disappears and we obtain a∗ = . with ψ ′(a∗ ) = − . (resp., a∗ = . with ψ ′(a∗ ) = . ). e equilibrium strategies and limits of the beauty contest anal- ogy we characterize first investors’ strategies. corollary . at a linear equilibrium, the strategies of an informed investor are given by x (si,p ) = a αe (ei [v] −p ) + αp −αe αe e [θ ], ( ) x (si,sp ,p ,p ) = a αe (ei [v] −p ). ( ) in the event of multiple equilibria, if a =  a ∗ then αp < αe , (∂xi /∂p ) < , covi [v −p ,p −p ] < ; a∗∗ ,a ∗∗∗ then αp > αe , (∂xi /∂p ) > , covi [v −p ,p −p ] > . ( ) if β = then αp < αe , (∂xi /∂p ) < , and covi [v −p ,p −p ] < . according to ( ), in the second period an investor behaves as if he were in a static market. so in the first period this investor loads his position while anticipating the second- period price and scaling it down according to his uncertainty regarding p (see ( )). in this case, the investor’s strategy can be expressed as the sum of two components (see ( )). the first component captures the investor’s activity based on his private estimation of the difference between the fundamentals and the equilibrium price. such activity is akin to “long-term” speculative trading that aims to take advantage of the investor’s superior information on the asset’s liquidation value (since p is correlated with v). the second component captures the investor’s activity based on the extraction of public information (i.e., order flow). this trading instead aims to time the market by exploiting short-run movements in the asset price related to the evolution of aggregate demand. along the hie, the price is closer to fundamentals. as a result, when observing e [θ ] = a (v −e [v]) + θ > the investor infers that this realization is mainly driven by fundamentals information; he therefore goes long in the asset, “chasing the trend”. this behavior reflects his anticipa- tion that second-period investors will bid the price up when he unwinds his position, as implied by the sign of covi [v−p ,p −p ]. along the “keynesian” lie, prices are driven more by liquidity trading and so the trader acts instead as a “contrarian” investor. this observation also suggests that the aggregate trading behavior of informed in- vestors differs across the two equilibria. in the lie, investors trade less aggressively on private information and thus exploit more aggressively the predictability of liquidity traders’ demand. the opposite occurs in the hie, where aggregate demand is driven by trading that is relatively more informed. we can demonstrate these claims formally by evaluating informed investors’ first-period aggregate position ∫ x (si,p ) di = x (v,p ), x (v,p ) = a αe (ē [v] −p ) + αp −αe αe e [θ ], ( ) and then computing the following covariances: cov [ a αe (ē [v] −p ),θ ] = − ( a τ + αp αe τv τ τu ) < ( a) cov [ αp −αe αe e [θ ],θ ] = αp −αe αe τv τ τu   < lie> hie ( b) the aggregate long-term speculative position is always negatively correlated with the noise shock (see ( a)). for the short-term aggregate position, this correlation is observed only in the lie (see ( b)). in other words, for a given noise shock realization, investors in the hie speculate against it according to the long-term component of their strategy while apparently trading along with it according to the short-term component. the intuition is that, along the hie, investors trade so aggressively on their private information that they more than offset the initial price deviation from fundamentals generated by θ . for example, if θ > then investors short the stock so aggressively that its price undershoots the fundamentals. in equilibrium, then, investors find it profitable to purchase shares based on order flow information. along the lie, investors trade less aggressively on private information and so the covariances of both the long- and short-term components of investors’ demand with liquidity traders’ demand have concordant signs. remark . it is interesting that, along the hie, the asset is a giffen good in the second period (see ( )). differentiating xi with respect to p , we can break down the effect of we can prove that ( a) is larger (in absolute value) at the hie than at the lie when τη = , and our numerical simulations indicate that this difference holds also when τη > . a price increase into a substitution effect and an “information” effect: ∂x (si,sp ,p ,p ) ∂p = a αe   ∂ei [v]∂p ︸︷︷︸ information effect − ︸︷︷︸ substitution effect   . ( ) along the hie, investors rely strongly on prices, which are extremely informative about liquidation value. in this case, the substitution effect is swamped by the information effect. along the lie, the opposite happens and the asset is a normal good in the second period. giffen goods often arise when the learning from uninformed investors prevails, in which case the aggregate information effect dominates the substitution effect (see, e.g., barlevy and veronesi ( ), yuan ( ), vives ( )). this could happen also in the presence of feedback effects when prices are informative both about the fundamentals and about the likelihood of coordination among informed investors, since the feedback effect would then strengthen the information effect (as in ozdenoren and yuan ( )). our last result in this section relates the two equilibria to the reliance of price on public information. corollary . suppose τη > . . let β ∈ ( , ], and assume there are multiple equilibria. in that case, if a =  a ∗ then αp < αe and cov[p ,v] < cov[ē [v],v], a∗∗∗ then αp > αe and cov[p ,v] > cov[ē [v],v]. . if β = , then αp < αe and cov[p ,v] < cov[ē [v],v]. if liquidity trading is persistent then, along the hie, investors escalate their response to private information. in this case the extra weight added to ᾱe (see ( )) is large enough to draw the price closer to fundamentals (than is the consensus), in contrast with allen, morris, and shin ( ). in view of the results obtained in section iii.d, this equilibrium is stable provided that private information is not too much more precise than see admati ( ) and cespa ( ) for discussions about the existence of giffen assets due to information effects in the context of a multi-asset ree model. to see this, observe that ∂xi /∂p = (a /αe )(∆a τu/λ τi − ) = −γτi /( + γ∆a τu). along the hie (resp., lie), as shown in proposition , +γ∆a τu < (resp., +γ∆a τu > ). these inequalities prove the result. the exogenous public signal. along the lie, the price is farther away from fundamentals compared to consensus. this equilibrium, which shares the same properties of the one found by allen, morris, and shin ( ), is always stable. remark . according to numerical result and corollary , the inventory component of liquidity is larger in the lie than in the hie. that difference suggests an alternative interpretation of corollary : when prices are farther away from (resp., closer to) fun- damentals as compared with the consensus, inventory risk is high (resp., low). from an empirical standpoint, the implication is that the inventory component of liquidity is in- creasing in the extent of the difference between how accurately fundamentals are assessed by asset prices versus the consensus. f robustness in this section we perform some robustness exercises. first, we extend our model to encompass the possibility that residual uncertainty affects the asset payoff. second, we show that a very similar pattern of equilibrium multiplicity arises in a model with long-term traders who face residual uncertainty about the final payoff. (our analysis of both these extensions is given in the online appendix.) finally, we discuss the effect of extending the number of trading rounds and allowing investors to receive more than one private signal. f. the effect of residual uncertainty assume that investors face residual uncertainty over the final liquidation value. that final payoff is written as v̂ = v + δ, where δ ∼ n( ,τ− δ ) is a random term orthogonal to all random variables in the market and about which no investor is informed. our inclusion of the random term δ allows one to study the effect of an increase in the residual uncertainty that characterizes the investing environment in periods of heightened turbulence. it is intuitive that, when investors face residual uncertainty, they put less weight on their own signals because prices and private information are less useful in predicting the asset payoff. this dynamic is likely to weaken the retrospective inference and variance reduction loop and may even eliminate the hie. yet our analysis shows that, in general, residual uncertainty neither eliminates the hie nor makes it unstable. even when there is residual uncertainty, the expressions for prices and investors’ strategies do not change (i.e., the expressions ( ), ( ), and ( ) still hold). however, the equilibrium obtains as the solution of a system of two highly nonlinear equations and is therefore more difficult to solve. numerical analysis establishes that: (i) an equilibrium akin to the lie always arises; (ii) for low values of /τδ there can be as many as five equilibria, and at least one of these will be a hie; (iii) if residual uncertainty is high then a unique equilibrium obtains and only lie-type equilibria survive. in our baseline simulation, we set τv = and find that, for τδ < , the hie vanishes. although at first blush a small level of residual uncertainty (e.g., σ δ ≤ / ) may seem to cast doubt on the hie’s relevance, it is possible to show that this parameterization is in line with calibrated asset pricing models. for instance, wang ( ) models the asset payoff as a dividend process ft+ = ρft + ωt+ , where ft is a persistent component and ωt+ an orthogonal random error term that corresponds to our residual uncertainty term. here the coefficient ρ parameterizes the effect of past fundamentals on current ones. in this framework, the fraction of variance coming from residual uncertainty is − ρ (i.e., the ratio of σ ω to the steady-state variance of ft+ or σ ω/( − ρ )), which in our framework corresponds to σ δ/(σ δ + σ v). it is easy to show that, for ρ ∈ (. , . ), residual uncertainty in the dynamic model is of comparable importance to that implied by the parameter τδ = . so if, for example, we take our model to represent trading patterns that occur at a quarterly frequency, then the previous statement implies (roughly) a critical value of ρ = . at a yearly frequency; that value is commonly used for calibration in asset pricing models. f. long-term investors consider again the market with residual uncertainty, but now suppose that investors have a long horizon and so maximize the expected utility of their final wealth. for simplicity we will address the case in which the public signal is useless (τη = ). we find that multiple equilibria are possible in this scenario as well, and the reasons are similar to those given for the case of short-term investors. a long-term investor in the first period speculates on short-term returns and takes into account the hedging possibilities of second-period trading. the equilibrium strategy of investor i in the first period is actually a linear combination of (ei [p ]−p ) and ei [xi ] (cespa and vives ( )). if traders do not expect prices to change, then their optimal period- position would be just as in a static market. the risk of holding such a position we are indebted to an anonymous referee for suggesting this calibration exercise. this strategy is of the form xi = Γ (ei [p ] − p ) + Γ ei [xi ], where Γ and Γ are equilibrium parameters and ei [xi ] = Λ − ( −λ ∆a )(ei [v] − p̂ ). would be due only to the liquidation value’s unpredictability. however, if a change in prices is expected then traders optimally exploit short-run price differences. two factors increase the risk of their period- position: the partial unpredictability of the price change; and the impossibility of determining their exact future position. nevertheless, the opportunity to trade again in the future does serve as a hedge against potentially adverse price movements. in equilibrium, this option reduces risk and thereby—in the absence of residual uncertainty—exactly offsets the price risk conditional on private information. so when there is no residual uncertainty, traders’ strategies incorporate static responses to private information and there is a unique equilibrium. in this case, the optimal strategy of an informed trader is static (i.e., buy and hold): in the first period, informed traders receive their private signal and take a position; in the second period, there is no informed trading. although investors may nonetheless speculate on price differences, they do so only for market-making purposes (i.e., to profit from the mean reversion of liquidity trading). when there is residual uncertainty, investors in the second period scale down their trading activity as the final payoff becomes harder to forecast. this weakens the hedging effect of the re-trading opportunity and renders strategies truly dynamic, leading investors to speculate on short- term price movements based on their private information. these consequences reinforce the retrospective inference and variance reduction loop and lead to multiple equilibria, since the market’s liquidity in the second period strongly affects a trader’s reaction to private information in the first period. in summary, with long-term and risk-averse investors there may be multiple equilibria when there is either residual uncertainty (he and wang ( ), cespa and vives ( )) or a common shock to private signals (grundy and mcnichols ( )). we may have situations then with a negative price impact in the second period. this arises because in those cases informed traders have incentives to use their private information to speculate on short-term price movements and long-term traders may behave as short-term ones. if the asset price is not expected to change in response to today’s information, then the market is not expected to receive any new private information and so the model collapses to one in which traders hold the risky asset for two periods. in that case, those positions naturally coincide with the ones they would hold in a static market. indeed, a long-term trader who faces uncertain impending liquidation will find his private signal to be of little use in period . as a result, such a trader will behave in the first period more like a short-term trader: he will try to unwind his first-period holdings in the market at time and thus carry little of that inventory to the liquidation date. f. more private signals, more trading rounds the model can be extended to encompass the possibility that investors trade for more than two periods and/or receive additional private signals during each round of trading. however, the analysis becomes more complicated without any effect on the qualitative re- sults. in particular, we can still show that multiple equilibria (with the stated properties) arise provided β > . iv asset pricing implications in this section we investigate the asset pricing implications of our analysis. first, we show that liquidity trading persistence can generate positive autocovariance of returns irrespec- tive of whether beliefs are heterogeneous (as in banerjee, kaniel, and kremer ( )) or whether investors’ preferences exhibit a behavioral bias (as in daniel, hirshleifer, and sub- rahmanyam ( )). second, we look at the expected volume of informational trading and then compare the model’s predicitons with predictions under “differences of opinion” models. third, we discuss identification problems in models with multiple equilibria and derive a set of empirical implications that allow one to distinguish the hie from the lie. finally, we show how our model can provide a narrative of some episodes related to the recent financial crisis. a return autocovariance we start by computing the return autocovariance at different horizons. corollary . suppose τη > . at equilibrium, the following statements hold. (i) for all β ∈ [ , ], cov[p −p ,p − v̄] < . (ii) for β ∈ ( , ], cov[v −p ,p − v̄] < ; for β = , cov[v −p ,p − v̄] = . (iii) for β ∈ ( , ], if there are multiple equilibria then—along the hie—we have cov[v− p ,p −p ] > . if β = , then cov[v −p ,p −p ] < . this result states that, along the hie, momentum always occurs at short horizons (i.e., near the end of the trading horizon) whereas the reversal of returns occurs at long horizons. numerical simulations in a three-period model show that, along the hie, both cov[v −p ,p −p ] and cov[p −p ,p −p ] are positive. parts (i) and (ii) of the corollary hold because a given estimated first-period imbalance e [θ ] has the opposite effect on p −v̄ as it does on both p −p and v−p . for part (iii), a covariance decomposition (and the normality of returns) yields: cov[v −p ,p −p ] = cov[e [v −p ],e [p −p ]] + cov [v −p ,p −p ] = βΛ vari [p ] γ var[e [θ ]] + ( + γτu∆a )(βa ∆a τu − τ ) + γτητuβa (γτi ) τ τu . ( ) the first term in this decomposition captures the covariation in forecasts of conditional returns, e [v−p ] and e [p −p ]—in other words, the covariance “explained” by p . the second term captures the conditional covariation of returns, the “residual” covariance. all else equal, if trading is persistent then the anticipated effect of the first-period imbalance on the second- and third-period expected returns is of the same sign; hence the first term is always positive when β > . suppose that investors in the first period estimate a selling pressure from liquidity traders. if p < p then the outcome p < v is more likely than is p ≥ v because liquidity traders’ sales of the asset are likely to persist in the second period. for the second term, factoring out the effect of first-period information suggests that the joint covariation of returns around their expectations could be driven either by liquidity trading or by fundamentals information. in the hie, prices are driven by informed traders; hence the second effect predominates and there is positive covariance of returns around their means. conversely, prices in the lie are more driven by liquidity trades and so returns tend to covary around their means in opposite directions. when τη = , all of the results obtained in corollary continue to hold. we can also prove that, for β sufficiently high, momentum occurs at short horizons also along the lie (numerical simulations confirm this result for the case τη > ). formally, we have the following statement. one can easily verify that cov[v−p ,p −v̄] = cov[e [v−p ],e [p −v̄]] = −βΛ cov[e [θ ],p ] < and cov[p −p ,p − v̄] = cov[e [p −p ],e [p − v̄]] = (βΛ − Λ ) cov[e [θ ],p ] < . suppose that e [θ ] < . then our pricing equation ( ) implies a reduction in p so that a risk- averse investor will be awarded higher expected returns, inducing her to absorb the shock. indeed, we have e [p − p ] = (βΛ − Λ )e [θ ] > . if β > then selling pressure is likely to persist, which implies that prices will be depressed again at date and will thus ensure positive expected returns: e [v −p ] = −βΛ e [θ ] > . in this way, the persistence of liquidity trades offsets the mean reversion effect resulting from the first period’s short-term investors’ unwinding at date . proposition shows that in this case +γτu∆a < , which by ( ) implies that cov [v−p ,p −p ] > . corollary . suppose τη = . then, along the lie, for τv < τ̂v there exists a value β̂ such that for all β > β̂, cov[v −p ,p −p ] > . (the expression for τ̂v is given in the appendix; see (a. ).) along the lie, momentum is a sign of strong liquidity trading persistence and is due to the effect of the covariance explained by p in ( ). this finding is consistent with prices in that equilibrium being driven by liquidity trades, so here the predictability of returns is a sign of poor informational efficiency. indeed, it is possible to show that, for β sufficiently large, momentum arises also in a model with no private information. along the hie, however, momentum occurs for any value of β ∈ ( , ]. this means that even though (a very mild) persistence is required, momentum in this case is not due to liquidity trading. to the contrary, the hie properties illustrated in proposition suggest that momentum here is rather a sign of rapid price convergence to the fundamentals. according to the “time series momentum” evidence, which spans a vast class of finan- cial instruments, the lagged -month excess return on a given asset is a good predictor of that same asset’s “one year ahead” return. in addition, moskowitz, ooi, and ped- ersen ( ) document the following patterns associated with time-series momentum: (i) hedgers (who in our setup can be proxied by liquidity traders) have stable positions for extended time periods and so induce a persistent price pressure, yielding continuation of returns; (ii) speculators benefit from time-series momentum by going long in an asset to exploit its anticipated price trend (at the expense of hedgers); (iii) the spot price of the asset underlying the futures reacts slowly to information. these patterns are con- sistent with behavior along the lie. indeed, along the lie, the covariance of the long- and short-term components of investors’ demand with liquidity traders’ demand has the same (negative) sign; see equations ( a) and ( b). the implication is that investors fully exploit the predictability of liquidity trades—while mildly offsetting their price im- pact with their information so that prices are driven by liquidity trades. under these conditions, it pays to exploit liquidity traders’ predictability precisely because so little of the information about fundamentals affects aggregate orders. b expected volume and return predictability we now address the implications of our results for the expected volume of informational trading. this claim can be demonstrated by computing limτε→ cov[v−p ,p −p ] = (β−γ τvτu)/γ τ uτ v, which implies that momentum in this case arises when β > γ τvτu. we start by computing the expected traded volume in the market with heterogeneous information net of the expected volume when there is no private information. we have v ≡ ∫ e[|x (si,p )|] di− ∫ e[|x (p )|] di = ∫ √ π var[x (si,p )] di− ∫ √ π var[x (p )] di = √ π (√ a τ − ε + τ − u − √ τ− u ) ( ) and v ≡ ∫ e[|x (si,p ,p ) −x (si,p )|] di− ∫ e[|x (p ,p ) −x (p )|] di = ∫ √ π var[ x (si,p ,p ) −x (si,p )] di− ∫ √ π var[ x (p ,p ) −x (p )] di = √ π (√ (a −a ) τ− ε + ( + (β − ) )τ− u − √ ( + (β − ) )τ− u ) . ( ) using v + v to measure the total volume of informational trading, we obtain the following result. corollary (expected volume of informational trading). suppose τη > . then, at equilibrium, for all β ∈ ( , ] the expected volume of informational trading is higher along the hie. when β = , only the equilibrium with a low volume of informational trading survives. proof. rearranging corollary ’s expressions for investor strategies yields xin = anεin − θn for n = , . for a normally distributed random variable y , we have e[|y |] = √ π var[y ]. since a∗∗∗ > a ∗ , it now follows from ( ) that v is larger along the hie. according to ( ), v + v is an increasing function of a for a > a , a condition that is satisfied along the hie. finally, by corollary , if β = then a∗ < a . the intuition for corollary is straightforward: because investors in the hie step up in a market with no private information, investors absorb only the orders of liquidity traders. in equilibrium, then, their positions reflect only liquidity traders’ demand and so e[|x |] = (( /π)τ− u ) / . this approach is taken by he and wang ( ), among others. their response to private signals, the position change due to private information is higher along such equilibrium. taken together, corollaries and imply that a high volume of informational trading in the second period predicts a continuation of returns regardless of how persistent liquidity trading is—a conclusion that accords with the evidence presented by llorente et al. ( ). yet a low volume of informational trading can also be associated with momentum as long as liquidity trading is persistent enough. however, momentum in this case signals slow price convergence to the liquidation value. in short, momentum is compatible with both a high volume and a low volume of informational trading, but the implications of continued returns for price informativeness are markedly different in the two situations. the extant literature typically associates volume realizations with investors’ diver- gence of opinions about the asset payoff (see, e.g, kandel and pearson ( )). in our setup, disagreement is measured as follows: disag = var [ ein[v] − ēn[v] ] = var[αenεi] = τε τ in . ( ) from this expression and proposition , we conclude that disagreement is low (high) along the hie (lie). this statement and corollary now imply the following. corollary . volume is high (resp., low) in the equilibrium with low (resp., high) levels of disagreement. this corollary accommodates recent empirical evidence on the relationship between the convergence of opinions and the trading volume around earnings announcements. indeed, giannini, irvine, and shu ( ) find that large volume is actually compatible with convergence of opinions—a result that runs counter to what most of the literature on transaction volume implies. their finding can be explained as follows. from expressions ( ) and ( ) it is clear that volume is increasing in a /τε. we now use ( ) and obtain a τε = ( γ λ ∆a vari [p ] ) var[αe εi]. ( ) the first component on the right-hand side of equation ( ) captures the effect of in- vestors’ perceived risk on volume; the second term coincides with our definition of dis- agreement. along the hie (lie), we know that disagreement is low (high) but we also know that investors face little (considerable) risk concerning the price at which their po- sitions unwind. the latter effect prevails in our setup, which implies that high trading volume is a good proxy for low disagreement and low perceived risk. our model predicts in addition that, when volume is high and opinions are converging, prices should serve as a reliable signal of the underlying fundamentals. finally, our findings on volume are also related to banerjee ( ) and kondor ( ). the former paper compares differences of opinion (do) models to rational expectations (re) models. one prediction is that in a do model, differently from a re one, the conditional volatility of returns is negatively related to expected volume. that relation is precisely the one found in our re setup with strategic complementarities (a coupling of corollary and numerical result ) even though investors agree on a common prior. hence we conclude that observing a negative correlation between trading volume and the conditional volatility of returns is insufficient grounds for rejecting a re model. on the contrary, this correlation may well indicate that the retrospective inference mechanism described in our model is responsible for the observed regularity. kondor ( ) stud- ies a two-period trading model with three-factor fundamentals and short-term traders who have factor-specific information. in his model, a public signal on the fundamentals generates disagreement because it leads traders to compare their factor-specific private information to the public signal and thereby gauge the magnitude of the factor about which they have no private information. the author shows that an increase in the infor- mativeness of public signals can, by facilitating disagreement, generate large volume as well as prices that are not only more informative but also more volatile (conditional on the public signal). our model can produce similar patterns for price volatility. however, in our setup the association between a burst in trades and higher price volatility results from a public signal that is precise enough to stabilize the hie. c stock price fragility according to greenwood and thesmar ( ), a fragile asset is one that is vulnerable to non-fundamental demand shocks. these authors find that ownership concentration increases asset fragility but also that the active trades of hedge funds and mutual funds can mitigate fragility by counteracting the effect of mutual funds’ flow-induced trades. for example, set τu = τv = , τε = , τη = . , γ = / , and β = ; then we obtain two stable equilibria, a∗ = . and a ∗∗∗ = . . by corollary , volume is higher along the hie. furthermore, calculating price volatility yields var[p ] ∗∗∗ = . and var[p |sp ]∗∗∗ = . , as compared with var[p ]∗ = . and var[p |sp ]∗ = . . thus, price volatility is larger in the hie compared to the lie in the first (resp. second) period. the idea is that if the mispricing induced by non-fundamental demand shocks becomes large enough, then hedge funds will step in to correct it by taking offsetting positions. along the hie, this hypothesis is in line with the mechanism outlined in ( a) and ( b). greenwood and thesmar ( ) find that the distribution of offsetting trades is extremely heterogeneous across stocks, with some stocks characterized by strong offsetting effects and with other stocks for which this effect is relatively weak. our analysis implies that the former stocks should be those for which the hie is likely to prevail and hence should be associated with the combination of high trading volume and converging opinions. conversely, we predict that stocks associated with low volume and diverging opinions should be more fragile. d identifying equilibria we know from jovanovic ( ) that models governed by multiple equilibria of structural parameters have severe identification problems and also that “the set of distributions on observable outcomes that are consistent with a given structure can be quite large.” pos- itive identification results are obtained in a range of papers that use simple models with multiple equilibria (e.g., discrete entry or binary games; see the accounts in ackerberg et al. ( ) and berry and tamer ( )). identification of structural parameters is achieved through equilibrium refinements, shape restrictions, informational assumptions, or the specification of equilibrium selection mechanisms. alternatively, inference can be based on the identified features of the models with multiple equilibria, which are sets of values of the structural parameter vector (see, e.g., ciliberto and tamer ( ) and the refinement in henry and galichon ( )). in the model developed here, with two stable equilibria there is no equilibrium re- finement or equilibrium selection mechanism to be used. given the presence of strategic complementarities in our model, a promising approach is the one of echenique and ko- munjer ( ) based on monotone comparative statics (mcs) results. unfortunately, the type of multiplicity that arises in our paper fails to satisfy mcs, which this literature requires for identification (see the online appendix). equilibria can nonetheless be identified based on their respective implications for spe- cific market observables. according to proposition , the inference component of the spread is negative along the hie and positive along the lie. at the same time, by nu- merical result and corollaries and we know that, in the hie, the conditional volatility of returns is low, trading volume is high, and these patterns occur with low disagreement. finally, corollary implies that in the hie there is mild positive autocor- relation of returns at short horizons. more insights on identifying the specific features of each equilibrium can be obtained by contrasting the qualitative properties of the hie and lie via numerical simulations. in what follows we assume that τv = . , τu = . , τε = , γ = / , τη = . , and β = / . with these values, a stable hie obtains ({a∗ ,a∗∗∗ } = { . , . } with {ψ′(a∗ ),ψ ′(a∗∗∗ )} = {− . ,− . }) and we obtain momentum along the lie and in the unique equilibrium with no private information (τε = ); see table . next we set v̄ = and extract , i.i.d. normal shocks for v, u , u , and η and then average across the prices and shocks. the results of this exercise are presented in figure , where we plot the positions of liquidity traders at dates and followed by the simulated price paths along the low-information equilibrium, the high-information equilibrium, and the equilibrium with no private information. lie hie equilibrium with τε = cov[v −p ,p −p ] . . . × cov [v −p ,p −p ] − . . − , cov[z ,p −p ] − . − . × − − . × e [v −p ] − . − . − , e [p −p ] − . − . × − − , table : autocovariance of returns (unconditional and conditional), return predictability from order flows, and expected returns from liquidity provision in the numerical example. panel (a) in the figure displays the position of liquidity traders, which in this simula- tion is (on average) positive at both dates. according to panel (b), if there is no private information then prices mirror liquidity traders’ demand. indeed, since short-term traders are risk averse, they require compensation—for satisfying the positive demand of liquidity traders—that is proportional to their perceived uncertainty about the payoff. that com- the green line in panels (b), (c), and (d) of the figure is the (log of the) average of the semi-strong efficient prices obtained in the simulations—that is, ln(( / ) ∑ j= enj[v]), n = , . the horizontal line in the plots for the price paths is the (log of the) average value of the fundamentals (in this simulation, ln( . ) ≈ . ). n . . . . . Θn (a) n log@en @vdd log@ pn d (b) n log@en @vdd log@ pn d (c) n . . . . log@en @vdd log@ pn d (d) figure : liquidity traders’ demand (panel (a)) and the path of prices (red) and semi- strong efficient prices (green) along the equilibrium with no private information, the lie, and the hie (respectively, panels (b), (c), and (d)). parameter values are as follows: v̄ = , τv = . , τu = . , τε = , γ = / , τη = . , and β = / . pensation drives p above v̄ in this equilibrium. in panel (c) of figure we see that prices display a qualitatively similar behavior along the lie. yet because traders are informed, an > and so part of liquidity traders’ shock is accommodated by offsetting speculative orders (in this numerical example, sell orders). these orders transmit information and thereby diminish investors’ perceived uncertainty about the payoff, which implies that the price adjustment needed to accommodate θn is lower than in the τε = case. in the lie, then, absent private information the price path reflects the liquidity traders’ position and is therefore hump-shaped. along the hie (panel (d)), in contrast, the first-period price coincides almost exactly with the semi-strong efficient price and with the full-information value. in this equilibrium, traders aggressively speculate (sell) against the liquidity (buy) shock θn based on their private information. this behavior drives p below v̄ and close to v, accelerating price adjustment. these trades are highly informative and thus dra- matically reduce investors’ perceived uncertainty about the payoff, which explains why the price nearly matches en[v] even though the market’s risk-bearing capacity is limited (γ < ∞). in this equilibrium, short-term trading offsets the impact of liquidity traders’ orders on prices, and the price path is inversely hump-shaped. these different patterns complement our findings and suggest that (i) the compensa- tion investors receive for supplying liquidity should be greater in the lie than in the hie and (ii) the short-term predictability of prices based on order flow information (z ) should be higher along the lie than along the hie. both predictions are confirmed by the last three rows of table . the latter prediction is also consistent with the evidence pre- sented by chordia, roll, and subrahmanyam ( ), who find that short-horizon return predictability from order flows declines when the market is more liquid. combining these observations with proposition and our previous results in sec- tion iv suggests a way to identify the hie and the lie from the data. our model predicts that the lie arises for extreme values of public signal precision (which could be proxied, e.g., by the number of analysts following a given security). this equilibrium is characterized by (i) a positive inference component of the price impact, (ii) momentum or reversal depending on the strength of trading persistence, (iii) high expected returns from liquidity provision, (iv) prices that are far from the semi-strong efficient price, (v) high short-horizon return predictability from order imbalances, and (vi) low volume accom- panied by high levels of disagreement. our model predicts that the hie may arise for intermediate values of public signal precision. this equilibrium is characterized by (i) a negative inference component of the price impact, (ii) mild momentum, (iii) low expected returns from liquidity provision, (iv) prices that are close to the semi-strong efficient price, (v) low short-horizon return predictability from order imbalances, and (vi) high volume accompanied by low levels of disagreement. see table , which summarizes the model’s empirical implications. the equilibrium predictions of table help us when using market data to distin- guish among equilibria and also when seeking to discriminate among different behavioral theories. the main implications of our findings can be listed as follows. . high volume associated with informative prices and low disagreement argues for the hie in relation not only to the lie but also to alternative theories based on differences of opinion and in which disagreement is associated with high volume. in the expected returns from liquidity provision are calculated per unit of expected demand from liquidity traders, e [θ ] = . since e [v − p ] = −βΛ e [θ ] and e [p − p ] = (βΛ − Λ )e [θ ], it follows that expected returns are due only to the inventory component of liquidity—consistently with our interpretation. β = β ∈ ( , ] lie hie reliance on public information high high low liquidity low low high price impact (period ) { + + − strong strong weak price informativeness low low high risky asset (period ) normal normal giffen expected volume of informational trading low low high return correlation at long horizons − − − return correlation at short horizons − ± + disagreement high high low conditional volatility high high low table : the beauty contest revisited. fact, an observation of high trading volume with high levels of disagreement would be inconsistent with our model at either the lie or the hie. . a negative covariance between conditional volatility and volume need not disqualify re models (as suggested by banerjee ( ), for example) because that finding is consistent with our results. . a negative inference component of the price impact identifies the hie and the oc- currence of return reversals at short horizons identifies the lie, with the maintained hypothesis that our model holds. . if for fragile (non-fragile) stocks—in the sense of greenwood and thesmar ( )— there is a low (high) volume transacted when there is high (low) disagreement, then that would constitute evidence for our lie (hie). in other words, fragility should be associated with low trade volume and divergence of opinions. e meltdowns finally, our model can also shed some light on episodes of sudden liquidity dry-ups as exemplified in severe form by the recent financial crisis. we offer an information-based explanation that complements the standard one given in terms of insufficient arbitrage capital. the quant meltdown of august . in the second week of august , several hedge funds started unwinding their holdings (arguably for non-informational reasons). khandani and lo ( ) show that the price impact of trades spiked during the event. their conclusion is that a lack of arbitrage capital (together with the increased importance of high-frequency trading for market making) was largely responsible for the meltdown. in our model, a large increase in price impact is consistent with an increase in the volume or volatility of liquidity trading and a switch from the hie to the lie (since then the hie may disappear; see figure (d)). in fact, the lie prevails also when the demand of liquidity traders becomes larger and more volatile. in that case, the retro- spective inference and variance reduction loop weakens and the high-liquidity equilibrium disappears. the alternative view is that even if capital had been abundant (with cara utilities there is no room for endowment effects), a similar meltdown could have occurred if informational conditions were like those that we find. the financial crisis and public information. several authors have argued that, during the – crisis, the selling pressure of investors drove asset values downward and below the fundamentals (though this was followed by a rebound; cella, ellul, and giannetti ( )). a possible reason for the occurence of such large corrections is the lack of (or “slow moving”) arbitrage capital (duffie ( )), which exhausted the risk- bearing capacity of liquidity suppliers. our theory provides an alternative explanation based on the absence of informational conditions that would have allowed for a milder correction. in particular, the dearth of reliable public information (proxied here by a steep reduction in τη) may have reduced the market’s risk-bearing capacity, relegating most of the economy to the lie. as argued in the online appendix, if the market coordinates at a hie that poor public information has rendered unstable, then an additional mild shock to public information leads this market to the lie. indirect evidence of such a transition is that “contrarian” liquidity providing strategies were extremely profitable during the for instance, gorton and metrick ( ) report that repo depositors during the crisis “did not know which securitized banks were most likely to fail.” financial crisis (as documented by nagel ( ))—in line with our prediction of the lie derived in section iv.d. with regard thereto our paper makes the additional prediction that, in the cross section, the assets that underwent the most extreme corrections were those for which the public information was poorest. v conclusions in this paper we argue that the persistence in liquidity traders’ positions has a significant effect on the response of risk-averse, short-term investors to their private signals. when the orders of liquidity traders are correlated across trading dates, investors reassess the evidence (about the fundamentals) obtained at the early trading stage based on the new information gathered in the market. such “retrospective” inference can generate strategic complementarities in the use of private information that in turn can yield multiple stable equilibria, and these equilibria can be ranked in terms of price informativeness, liquidity, and volatility. our analysis reveals that, if uninformed orders are predictable, then the effect of investors’ short horizons on market observables depends on the quality of public infor- mation. when public information is not much more precise than private signals, the retrospective inference channel is not too strong; in this case, a stable equilibrium arises that is characterized by low volatility, high liquidity, high price informativeness, high volume, and low levels of disagreement. this equilibrium exists alongside another equi- librium in which prices are more volatile and less informationally efficient, the market is thinner, volume is low, and disagreement is high. when public information is either very precise or very poor, the low-volatility equilibrium disappears or becomes unstable while the high-volatility equilibrium survives. thus our analysis indicates that there could be a nonlinear effect of public information on market observables. furthermore, our results can guide the empirical literature investigating the effect of investors’ horizons on market patterns as a means of identifying the stock characteristics associated with the high- or low-volatility equilibrium. our paper also clarifies the role of higher-order expectations in asset pricing. with liquidity trading persistence, prices are driven by average expectations about fundamen- tals and about liquidity trading. this dynamic, in contrast to the beauty contest results of allen, morris, and shin ( ), can draw prices either systematically farther away from nagel ( ) finds that the stocks of small, illiquid, and highly volatile companies generated the largest contrarian returns during the financial crisis. or closer to fundamentals—along the lie and the hie, respectively—as compared with the consensus of investors. we show that when public information is either very precise (compared with private signals) or very poor, prices are farther away from fundamentals compared to consensus. however, a public signal of intermediate precision makes the hie stable, thereby drawing prices closer (than consensus) to the fundamentals. we also link the hie and lie to the magnitude of the inventory component of liquidity, to the price impact, and to the returns from liquidity supply. thus, our analysis establishes the limits of the beauty contest analogy for financial markets and provides empirical implications to assess the effect of hoes on asset prices. table summarizes the empirical implications of our model. we provide the observ- ables that can discriminate among equilibria (under our model’s hypothesis) and among behavioral theories as well. high trading volume associated with low conditonal volatil- ity and low disagreement discriminates in favor of our hie against not only the lie but also alternative, do theories wherein disagreement is associated with high volume. furthermore, a negative covariance between conditional volatility and volume does not preclude the validity of rational expectations models because it is consistent with our model. we find also that fragility (in the sense of greenwood and thesmar ( )) should be associated with low transacted volume and divergence of opinions. in addition, our paper provides an alternative interpretation for empirically documented regularities in the patterns of return autocorrelation. the literature has only recently begun to in- vestigate the relationship between empirical regularities, such as the momentum effect, and the role of hoes in asset prices (see, e.g., verardo ( )). our paper 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(a. b) rearranging (a. ) we obtain p = αp a (a v −βa v + βa v + θ ) + ( −αp )e [v] =  αp a + ( −αp ) ∆a τuτ ︸︷︷︸ λ  z + τητi sp + γτ e [v] + βz γτi = λ z + τη τi sp + βαp a z + ( −αp ) τ τ e [v], (a. ) which provides an alternative expression for p which separates the impact on second period “news” from the information contained in the first period price and the public signal. in the first period owing to cara and normality, an agent i trades according to x (si,z ) = γ ei [p ] −p vari [p ] , (a. ) where, using (a. ), ei [p ] = ( λ ∆a + τη τi ) ei [v] + γτ e [v] + βz γτi , (a. ) vari [p ] = ( λ ∆a + τη τi ) τi + λ τu + τη τ i . (a. ) replacing (a. ) and (a. ) in (a. ) yields x (si,z ) = γ (λ ∆a + τη/τi )ei [v] vari [p ] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) − γ vari [p ] p = a si + a τ τε e [v] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) − γ vari [p ] p , where a = γ (λ ∆a + τη/τi )αe (λ ∆a + τη/τi ) /τi + λ /τu + τη/τ i . (a. ) imposing market clearing: x + θ = , which implies a v + θ + a τ τε e [v] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) = γ vari [p ] p . finally, solving for the equilibrium price and collecting terms yields p = a ( vari [p ] γ + βαp a ) ︸︷︷︸ αp ( v + θ a ) + ( −αp )e [v]. (a. ) proof of corollary in the second period, rearranging (a. ), p = e [v] + Λ e [θ ], where Λ = vari [v]/γ. in the first period, from (a. ) we have αp = a ( vari [p ] γ + β vari [v] γ ) . by definition of the inventory component obtained in ( ), Λ = αp /a . this implies Λ = vari [p ] γ + β vari [v] γ . proof of corollary for the second period price, see (a. ). for the first period price, we rearrange (a. ) to obtain p =  αp a + ( −αp )a τuτ ︸︷︷︸ λ  z + ( −αp )τvτ v̄. (a. ) proof of proposition to prove existence it suffices to note that in the first period, the equilibrium responsiveness to private information is defined by the fixed points of the following function ψ(a ) = γ (λ ∆a + τη/τi )αe (λ ∆a + τη/τi ) /τi + λ /τu + τη/τ i . (a. ) by inspection φ(a ) ≡ a −ψ(a ) = is a quintic in a , and therefore always possesses a real root. note that at equilibrium a > , otherwise λ ∆a > , which in view of (a. ) yields a contradiction. suppose that β > . to prove multiplicity we proceed as follows. note that φ( ) = −γ τετu(a + γ(τη + a τu))(τε + τη + a τu + τv) < (a. a) φ(a ) > . (a. b) therefore, there exists an equilibrium a∗ ∈ ( ,a ). next, evaluating φ(·) at a = + γτua γβτu , yields φ ( + γτua γβτu ) > , while evaluating it at a = + γτua γβτu , yields φ ( + γτua γβτu ) < , provided β > (a. a) γ τετu > ( β − ) − β (a. b) τη ≤ τ̂η ≡ ( / β − / )γa τ u + / a τu(β − / ) + γa τu( / −β) . (a. c) therefore, provided (a. a), (a. b), and (a. c) are satisfied, a second equilibrium a∗∗ exists in the interval ( + γτua γβτu , + γτua γβτu ) . given that φ(·) is a quintic, it must have an odd number of roots, which implies that when (a. a), (a. b), and (a. c) are satisfied at least another equilibrium a∗∗∗ must exist in the interval ( + γτua γβτu ,∞ ) . given the location of the roots we can conclude that < a∗ < a < a ∗∗ < a ∗∗∗ . further- more, we have + γτu∆a =   > for a = a ∗ < for a ∈{a∗∗ ,a∗∗∗ } which implies that λ∗ > , while λ ∗∗ < , and λ ∗∗∗ < . finally, we prove that price informativeness increases across the three equilibria. for τ this is immediate, since it increases in a . for τ as one can verify, given that a ∗ < a < a ∗∗ we have τ ∗ < τ ∗∗ . furthermore, for a > ( + γτua )/(γβτu), ∂τ ∂a > , which implies τ∗∗ < τ ∗∗∗ . suppose now that β = . then, φ(·) becomes a cubic in a : φ(a ) = a τu(( + γa τu) + γ τuτν) −a γ a τ u(a τu + τε + τν) (a. ) + a ( a τu(a ( + γa τu) + γτν) + τv(( + γa τu) + γ τντv) + τε + γ τu(τν + a τu) ) −γ a τu(a τu + τε + τν)(τv + a τu + τε + τν), with a negative discriminant. this implies that with β = there exists a unique equilib- rium in linear strategies with first period responsiveness a∗ . to locate the equilibrium, note that φ ( γ a τu(a τu + τε + τν) + γ τu(a τu + τε + τν) ) = − γ a τντu(a τu + τε + τν) + γ τu(a τu + τε + τν) < (a. a) φ(a ) = a (τv + τε( + γ τu(τν + τε( + γa τu) + τv))) > . (a. b) therefore, a∗ ∈ ( γ a τu(a τu + τε + τν) + γ τu(a τu + τε + τν) ,a ) . furthermore, since ψ′(a ) ∝ a τu(γ a τu(a τu + τε + τν) −a ( + γ τu(a τu + τε + τν)), we also have that for β = , the weights to private information in the first period are strategic substitutes. proof of corollary for any β ∈ [ , ], in the second period an equilibrium must satisfy a = γτε. in the first period, assuming τη = , and using (a. ), at equilibrium a equilibrium must satisfy φ (a ) ≡ a λ (τ + τε) −γτε∆a τu = a ( + γτu∆a ) −γ τε∆a τu = . (a. ) the above equation is a quadratic in a which for any a > and β > possesses two positive, real solutions: a∗ = + γτua ( + β) − √ ( + γτua ( + β)) − β(γτua ) βγτu (a. ) a∗∗ = + γτua ( + β) + √ ( + γτua ( + β)) − β(γτua ) βγτu , (a. ) with a∗∗ > a ∗ . this proves that for β > there are two linear equilibria. inspection of the above expressions for a shows that βa ∗ < a , while βa ∗∗ > a . the result for λ , var [p ] follows from substituting (a. ) and (a. ), respectively in λ and var [p ]. to see that prices are more informative along the hie note that in the first period var[v|z ]− = τ = τv + a τu. in the second period, the price along the hie is more informative than along the lie if and only if ( + β + γa τu(( −β ) + β( + β ))) √ ( + γa τu( + β)) − β(γa τu) γ β τu > , which is always true. given that τi = τ + τε, this also implies that Λ ∗∗∗ < Λ ∗ . finally, substitution of (a. ) and (a. ) in vari [p ] shows that vari [p ] ∗∗∗ < vari [p ] ∗. in view of ( ) this implies that Λ∗∗∗ < Λ ∗ . when β → , along the hie we have lim β→ + γτu(a + βγτε) + √ + γτu( (a + βγτε) + γτu(a −βγτε) ) βγτu = ∞, while along the lie, using l’hospital’s rule, lim β→ + γτu(a + βγτε) − √ + γτu( (a + βγτε) + γτu(a −βγτε) ) βγτu = γa τu + γa τu . from (a. ) it then follows that in this case αp < αe . finally, defining a∗ = γa τu + γa τu , and taking the limit of λ as β → when a = a∗ yields lim β→ λ∗ = + γτua γ(τv + (a ∗ ) τu + a τu + τε) > , whereas limβ→ λ ∗∗∗ = . proof of corollary starting from the lie, we need to verify that |ψ′(a∗ )| < , or that when a = a∗ , γβa τu < ( + γτu∆a ) . substituting (a. ) on r.h.s. of the above inequality and rearranging yields |ψ′(a∗ )| < ⇐⇒ − ( + a γτu( −β))( + a γτu( −β) + √ ( + γτua ( + β)) − β(γτua ) ) < , which is always satisfied. for the hie, we need instead to verify that |ψ′(a∗∗∗ )| > , or that when a = a ∗∗∗ , γβa τu > ( + γτu∆a ) . substituting (a. ) on r.h.s. of the above inequality and rearranging yields |ψ′(a∗∗∗ )| > ⇐⇒ ( + a γτu( −β))(−( + a γτu( −β)) + √ ( + γτua ( + β)) − β(γτua ) ) > , which is always satisfied, since the first factor in the product on the r.h.s. of the above expression is positive, while manipulating the second factor shows that √ ( + γτua ( + β)) − β(γτua ) > ( + a γτu( −β)) ⇐⇒ a βγτu > . proof of corollary in the second period, the result follows from the fact that since at equilibrium a = γτε, a αe = γ vari [v] . in period we have x (si,z ) = γ (λ ∆a + τη/τi )ei [v] vari [p ] + γ vari [p ] ( βαp a z + ( −αp ) τ τ e [v] ) − γ vari [p ] p . adding and subtracting (a /αe )p from the right hand side of the above expression yields x (si,z ) = a αe (ei [v] −p ) + ( a αe − γ vari [p ] ) p + γ vari [p ] ( β γτi z + τ τi e [v] ) . the second and third terms in the above expression can be rewritten to obtain( a αe − γ vari [p ] ) p + γ vari [p ] ( β γτi z + τ τi e [v] ) = β( −αp ) −γτ αp a τi vari [p ] e [θ ] = αp −αe αe e [θ ]. note, also, that setting ρ ≡ a /a , we can express αp = αe ( + (βρ− )τ τi ) . (a. ) this implies that for a = a ∗ , αp < αe , whereas the opposite holds for a ∈{a∗∗ ,a∗∗∗ }. to differentiate xi with respect to p , we first express the information contained in a trader’s forecast in terms of p . to this end we use (a. ) and write z = λ ( p − τη τi sp − βαp a z − ( −αp ) τ τ e [v] ) . substituting the above in ei [v], and differentiating xi with respect to p yields ∂xi ∂p = − γτi + γτu∆a . for a = a ∗ , we know that ∆a > , so that the information effect reinforces the substi- tution effect and the asset is a normal good. conversely, when multiple equilibria arise, for a ∈{a∗∗ ,a∗∗∗ }, + γτu∆a < , implying that the asset is a giffen good. finally, to compute the conditional covariance we have covi [v −p ,p −p ] = covi [v −p ,p ] = covi [v,p ] − vari [p ]. (a. ) using ( b), we obtain covi [v,p ] = τi ( λ ∆a + τη τi ) . on the other hand, from (a. ) we have vari [p ] = τi ( λ ∆a + τη τi ) + λ τu + τη τ i . substituting these expressions in (a. ) and rearranging yields covi [v −p ,p −p ] = − γτi τi ( λ (τi − τη) τu + ∆a τη τi ) . according to proposition , when a ∈ {a∗∗ ,a∗∗∗ }, ∆a < and λ < . therefore, covi [v −p ,p −p ] > . conversely, along the lie, the opposite occurs. proof of corollary we have already established in corollary that along the hie (lie) αp > αe (αp < αe ). now, using ( ) the covariance between p and v is given by cov[v,p ] = αp τv + ( −αp ) ( τv − τ ) , (a. ) and carrying out a similar computation for the first period consensus opinion cov [ ē [v],v ] = αe τv + ( −αe ) ( τv − τ ) . (a. ) we can now subtract (a. ) from (a. ) and obtain cov [ p − ē [v],v ] = αp −αe τ , (a. ) implying that the price at time over relies on public information (compared to the optimal statistical weight) if and only if the covariance between the price and the funda- mentals falls short of that between the consensus opinion and the fundamentals. proof of corollary to compute cov[p −p ,p − v̄] we first note that cov[p −p ,p − v̄] = cov[p ,p ] − var[p ]. (a. ) next, cov[p ,p ] = cov[e [p ],e [p ]] + cov [p ,p ] = cov[e [p ],p ]. computing cov[e [p ],p ] = var[e [v]] + (Λ + βΛ )cov[e [v],e [θ ]] + βΛ Λ var[e [θ ]] = a τ τ τv + (Λ + βΛ ) a τ + βΛ Λ τv τ τu , and var[p ] = a τu τ τv + Λ τv τ τu + Λ a τ . substituting these expressions in (a. ) and rearranging yields cov[p −p ,p − v̄] = − vari [p ] γ ( Λ τv τ τu + a τ ) < . consider now cov[v −p ,p − v̄], decomposing the covariance yields cov[v −p ,p − v̄] = cov[e [v −p ],p ] + cov [v −p ,p − v̄]︸︷︷︸ = = −βΛ (cov[e [θ ],e [v]] + Λ var[e [θ ]]) = −βΛ ( a τ + Λ τv τ τu ) = −βΛ λ τu , which is always negative for β ∈ ( , ], and null for β = . finally, to compute cov[v − p ,p −p ] we decompose again the covariance cov[v −p ,p −p ] = cov[e [v −p ],e [p −p ]] + cov [v −p ,p −p ]. computing, e [v −p ] = −βΛ e [θ ], and e [p −p ] = (βΛ − Λ )e [θ ]. therefore, cov[e [v −p ],e [p −p ]] = βΛ vari [p ] γ var[e [θ ]]. (a. ) next, we obtain cov [v −p ,p −p ] = ( + γτu∆a )(βa ∆a τu − τ ) + γτητuβa (γτi ) τ τu . (a. ) when a ∈ {a∗∗ ,a∗∗∗ }, ∆a < −(γτu)− , and the above expression is always positive, which implies that along the hie cov[v −p ,p −p ] > . proof of corollary to prove this result, we impose τη = in (a. ) and (a. ), obtaining cov[v −p ,p −p ] = − λ γτi τu ( −β∆a τi − τv a τi ) . (a. ) looking at (a. ) we again verify that along the hie there is momentum. this is true because in that equilibrium λ < and ∆a < . along the lie momentum can occur, depending on the persistence of liquidity trades. to see this, note that since in this equilibrium λ > and ∆a > , from (a. ) momentum needs −β∆a τi − τv a τi < , which can be rearranged as an (implicit) condition on the magnitude of β: a τi ∆a (τi − τv) < β < . if β = , the above condition is never satisfied. indeed, in this case there exists a unique equilibrium in which ∆a = a > . therefore, when β = returns always display reversal. if β = , the condition is satisfied if a τv + a (τε + a τu) < ∆a τu(τε + a τu). isolating τv in the above expression yields: τv < τ̂v ≡ (∆a −a )(τε + a τu) a , (a. ) which, since a does not depend on τv (see (a. )), gives an explicit upper bound on τv. hence, if τv < τ̂v, there exists a β̂ such that for all β ≥ β̂, when τη = , momentum occurs between the second and third period returns along the lie. b online appendix b. non-monotone comparative statics and dynamic adjust- ment what is the effect of a shock to parameters’ values on the equilibrium of the market? the answer to this question depends on whether the hie is stable or not. starting from the case in which the hie is stable, figure in the paper (panel (b)) implies that a decrease in private signal precision or in risk tolerance can have a non- monotone effect on a and thus on the conditional volatility of returns, and informational efficiency of prices. to see this, consider first the case of private signal precision. suppose that τv = τu = , τε = . , γ = / , τη = , and β = . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and correspond to the intersection of the orange best response function with the -degree line in figure (panel (a)). suppose the market coordinates on the lie. suppose now that the precision of the private signal decreases to τε = . the new best response is depicted by the dashed curve in the figure. again we have three equilibria with the lie and hie given respectively by a ∗,new = . , and a ∗∗∗,new = . . which equilibrium does the market coordinate on? with adaptive dynamics, we can see that this will be the hie. thus, in this case a decrease in private signal precision determines an increase in the response to private information and informational efficiency, and a decrease in the conditional volatility of returns (along the initial lie, var [p ] = . , while along the new hie, var [p ] = . ). non-monotonicity requires however a sufficiently large reduction in private precision. indeed, in panel (b) we repeat the same exercise, assuming that τε is lowered to . in this case, adaptive dynamics implies that the new equilibrium along the dashed best response is the lie. panel (c) and (d) show that similar effects arise with a reduction in risk tolerance. consider now the case in which the hie is unstable. in this situation numerical simulations show that starting from the hie, the effect of a shock (even a very mild one) to parameters’ values depends on the persistence of liquidity traders’ demand. in detail: in both cases the hie is stable case since (∂ψ/∂a )|a =a∗∗∗ = −. , and (∂ψ/∂a )|a =a∗∗∗,new = . . denoting respectively by ψ and ψnew the orange and dashed best responses, non monotonicity requires that that ψ(a∗ ) > ψ new (a ∗∗,new ). if the reduction in private precision is such that ψ(a ∗ ) > ψnew (a ∗∗∗,new ), the new equilibrium along the dashed best response is still the hie, but monotonicity is restored since a ∗∗∗,new < a ∗ . a Ψha l ΤΕ = ΤΕ = . (a) a Ψha l ΤΕ = ΤΕ = . (b) a Ψha l Γ= � Γ= � (c) a Ψha l Γ= � Γ= � (d) figure : adjustment to a shock when the hie is stable. we plot the best response ( ) for τv = τu = , γ = / , τη = , β = , and τε = . (orange). in panel (a) and (b) we analyze the effect of a reduction in the precision of the private signal to τε = (dashed best response, panel (a)) and τε = (dashed best response, panel (b)). in panel (c) and (d) we analyze the effect of a reduction in risk tolerance to γ = / (dashed best response, panel (c)) and γ = / (dashed best response, panel (d)). when β ∈ ( , ), the equilibrium converges to the lie; when β = , the market oscillates between two non-equilibrium values. in figure , panel (a) we plot the best response for τv = τu = , τε = , γ = / , τη = / , and β = . . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ ′(a∗∗∗ ) = − . . as shown in the figure, perturbing the hie an iterated application of the best response leads the market to coordinate on the lie. consider now panel (b) where we plot the best response for τv = τu = , τε = , γ = / , τη = / , and β = . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ ′(a∗∗∗ ) = − . . in this case, iterating the application of the best response perturbing the hie (after about iterations) leads the market to oscillate between the non-equilibrium values . and . . thus, the implication is that, provided β < , if the market is at the hie a small shock to parameter values leads it to the lie. a yha l (a) a yha l (b) figure : adjustment to a shock when the hie is unstable. in panel (a) we plot the best response ( ) for τv = τu = , τε = , γ = / , τη = / , and β = . . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ′(a∗∗∗ ) = − . . in panel (b) we plot the best response ( ) for τv = τu = , τε = , γ = / , τη = / , and β = . with these parameter values, the lie and hie are respectively a∗ = . , and a ∗∗∗ = . , and the slope of the best response at these two points is given by ψ′(a∗ ) = −. and ψ ′(a∗∗∗ ) = − . . b. the effect of residual uncertainty in this section we perform a robustness exercise and assume that investors face residual uncertainty over the final liquidation value. therefore, we model the final payoff as v̂ = v + δ, where δ ∼ n( ,τ− δ ) is a random term orthogonal to all the random variables in the market, and about which no investor is informed. the addition of the random term δ allows to study the effect of an increase in the residual uncertainty that surrounds investors’ environment in periods of heightened turbulence, and shows that a price crash can occur within our framework. intuitively, when investors are faced with residual uncertainty, they put less weight on their signals, since prices and private information are less useful to predict the asset payoff. this is likely to weaken the retrospective inference and variance reduction loop, eliminating the hie. our analysis shows, however, that in general residual uncertainty does not eliminate the hie, nor makes it unstable. with residual uncertainty, the expressions for prices and investors’ strategies do not change (that is, expressions ( ), ( ), and ( ) in the paper hold). however, the equi- librium obtains as the solution of a system of the following highly non-linear equations: a = fa (a ,a ) ≡ γτε + κ (b. a) a = fa (a ,a ) ≡ γ τi (∆a ( + κ + γτu∆a ) + γτη)τετu (∆a ( + γτu∆a + κ) + γτη) τu + τi (( + γτu∆a + κ) + γ τητu) . (b. b) inspection of the cubic (b. a) shows that it possesses a unique real solution, which can therefore be substituted in (b. b) to solve the equilibrium as a fixed point of a best response in a , fa (a ,a (a )). in f figure we show the plot of such a best response mapping for the following parameterization: τu = τv = , τε = , τη = / , γ = , β = / , and τδ ∈ { , , , }. when τδ = , we have equilibria, only two of which are stable with respect to best response dynamics. furthermore, the equilibrium with a higher value of a displays a negative inference component of liquidity, as shown by the first row of table b. . this suggests that, when retrospective inference is not too strong, the presence of residual uncertainty per-se is not sufficient neither to make the hie disappear, nor to make it unstable. of course, as residual uncertainty increases, the strength of the loop weakens even more and the hie tends to disappear as shown by panels (b), (c), and (d) in the figure, where we plot the best response for τδ = , τδ = , and τδ = . table b. collects the results of our calculations for the different values of τδ. τδ {(a∗ ,ψ ′(a∗ )),a ∗ ,λ ∗ } {(a∗∗ ,ψ ′(a∗∗ )),a ∗∗ ,λ ∗∗ } {(a∗∗∗ ,ψ ′(a∗∗∗ )),a ∗∗∗ ,λ ∗∗∗ } {(a∗∗∗∗ ,ψ ′(a∗∗∗∗ )),a ∗∗∗∗ ,λ ∗∗∗∗ } {(a∗∗∗∗∗ ,ψ ′(a∗∗∗∗∗ )),a ∗∗∗∗∗ ,λ ∗∗∗∗∗ } {(. ,−. ), . , . } {( . , . ), . ,−. } {( . ,−. ), . ,−. } {( . , . ), . ,−. } {( . ,− . ), . ,−. } {(. ,−. ), . , . } {( . , . ), . ,−. } {( . , . ), . ,−. } {( . , . ), . ,−. } {( . ,− . ), . ,−. } {(. ,−. ), . , . } {( . , . ), . ,−. } {−−,−−} {−−,−−} {( . ,− . ), . ,−. } {(. ,−. ), . , . } {−−,−−} {−−,−−} {−−,−−} {−−,−−} table : equilibrium values and values of the derivative of the best response mapping at equilibrium for the plots of figure . a yha l (a) a yha l (b) a yha l (c) a yha l (d) figure : the best response mapping in the model with residual uncertainty. parameters’ values are τu = τv = , τε = , τη = / , γ = , and β = . when τδ ∈ { , }, five equilibria obtain, only two of which are stable (respectively, panel (b), and (a)). when τδ = , only the lie is stable (panel (c)). when τδ = , only the lie survives (panel (d)). in our baseline simulation, we set τv = , and find that for τδ < , the hie vanishes. while at first blush this small level of residual uncertainty may seem to question the relevance of the hie, it possible to show that this parameterization is not uncommon in calibrated asset pricing pricing models. for instance, wang ( ) models the asset payoff as a dividend process ft+ = ρft + ωt+ , where ft is a persistent component, and ωt+ an orthogonal random error term, which corresponds to our residual uncertainty term. the coefficient ρ in this case parameterizes the impact of past fundamentals on current ones. the fraction of variance coming from residual uncertainty in this framework is −ρ (that is, the ratio between σ ω and the steady-state variance of ft+ , which is σ ω/( −ρ )), which in our framework corresponds to τ− δ /(τ − δ + τ − v ). it is easy to show that with a value of ρ ∈ (. , . ), residual uncertainty in the dynamic model has a comparable importance as the one implied by the parameter τδ = . thus, if for example we take our model to represent trading patterns that occur at a quarterly frequency, this roughly implies a critical value of ρ = . at a yearly frequency, which is not uncommon as a calibration in asset pricing models. b. long-term investors consider the market with residual uncertainty but assume that now investors have a long horizon and maximize the expected utility of final wealth. for simplicity we will deal with the case where the public signal is useless (τη = ). in this case multiple equilibria are also possible and the reasons are similar to those of the case with short-term investors. a long-term investor in the first period speculates on short-term returns and takes into account the hedging possibilities of second period trading. the equilibrium strategy of investor i in the first period is in fact a linear combination of (ei [p ]−p ) and ei [xi ] (cespa and vives ( )). were traders not to expect a change in prices, then their optimal period position would be like the one of a static market, and the risk of holding such a position would only be due to the unpredictability of the liquidation value. if a change in prices is expected, traders optimally exploit short-run price differences. two factors add to the risk of their period position, as traders suffer from the partial unpre- dictability of the price change, and from the impossibility of determining exactly their future position. however, the opportunity to trade again in the future also grants a hedge against potentially adverse price movements. this, in equilibrium, yields a risk-reduction which when there is no residual uncertainty exactly offsets the price risk conditional on private information. as a consequence, with no residual uncertainty, traders’ strategies we are indebted to an anonymous referee for suggesting this calibration exercise. it is of the form xi = Γ (ei [p ]−p ) + Γ ei [xi ] where Γ and Γ are equilibrium parameters and ei [xi ] = Λ − ( −λ ∆a )(ei [v] − p̂ ). intuitively, if given today’s information the asset price is not expected to change, no new private information is expected to arrive to the market and the model collapses to one in which traders hold for two periods the risky asset. their position, then, naturally coincides with the one they would hold in a static market. have a static nature in their response to private information. still investors may spec- ulate on price differences but only for market making purposes to profit from the mean reversion of liquidity trading. with residual uncertainty strategies are truly dynamic and informed investors speculate on short-term price movements based on their private information. we have that in equilibrium the responsiveness to private information (when informed traders do not receive a new signal in the second period as in our base model, see cespa and vives ( )) is given by: a = γτε( + γτu∆a ) + κ + γτu∆a , a = γτε + κ . when κ = then a = a = γτε. with long-term investors, and under the assumptions of the model, the feed-back loop that generates multiplicity is broken because the optimal strategy of an informed trader is static (buy-and-hold): in the first period informed traders receive their private signal, take a position and then in the second period there is no informed trading, the informed traders just make the market absorbing the demands of liquidity traders. when κ > , a = ργτε/( + κ) with ρ > at any equilibrium. the endogenous parameter ρ captures the deviation from the long term private signal responsiveness due to the presence of residual uncertainty. thus, prior to the last trading round, investors react to their private signals more aggressively than if the liquidation value were to be realized in the next period. indeed, while residual uncertainty makes investors less confident about their signals, the presence of an additional trading round increases the opportunities to adjust suboptimal positions prior to liquidation. this, in turn, boosts investors’ reaction to private information. residual uncertainty implies that informed investors speculate on short-term price movements based on their private information. this makes possible multiple equilibria. indeed, faced with uncertain impending liquidation a long-term trader in period is not going to use much his private signal. this makes the trader behave in in fact, when β = we have that xi = e[xi |si,p ]. when β < traders speculate also on price changes based on public information. if informed traders were to receive a second signal in the second period then there would be informed trading in this period but still the strategies would be static and price impact would still be positive. the reason is that the trading intensity in the second period will always be larger than the one in the first period, a = γ (τε + τε ) > a = γτε, because private information about the liquidation value accumulates over time. with long-term traders we can not have negative price impacts when the joint information of traders reveals the liquidation value. the first period more like a short-term trader since he will try to unwind his first period holdings in the market at time , and carry little of that inventory to the liquidation date. in this case the liquidity of the second period market becomes much more important to determine the trader’s reaction to private information in the first period and multiple self- fulfilling expectational loops are possible as in the case with short-term traders. again the possibility of multiple equilibria is linked to having a negative price impact in the second period (λ < ) due to a large response to private information in the first period (generating ∆a < ). for example, three equilibra arise with τδ = ,τε = τv = τu = γ = and β = . and only in the low a equilibrium we have ∆a > and stability. in general three equilibria are obtained for high β and high τδ. multiple equilibria may arise also when there is a common shock in the private signal (grundy and mcnichols ( )). in summary, with long-term risk averse investors and either residual uncertainty (he and wang ( ), and cespa and vives ( )), or a common shock in the private signals (grundy and mcnichols ( )) there may be multiple equilibria. we may have situations then with a negative price impact in the second period. this arises because in those cases informed traders have incentives to use their private information to speculate on short-term price movements and long-term traders may behave as short-term ones. cover page cespa the beauty contest.pdf st-model-november- - .pdf appendix online appendix non-monotone comparative statics and dynamic adjustment the effect of residual uncertainty long-term investors microsoft word - beauty and intelligence - wp - kevin denny geary wp/ / ucd geary institute discussion paper series beauty and intelligence may- or may not- be related dr. kevin denny ucd school of economics & geary institute, university college dublin, belfield, dublin tel: + kevin.denny@ucd.ie th february my thanks to orla doyle, charlotte faurie and kenneth mckenzie for comments. the author is also affiliated to the institute for fiscal studies, london. permission to use the national child development survey given by the esrc data archive at essex is gratefully acknowledged, the views expressed here do not necessarily reflect those of the geary institute. all errors and omissions remain those of the author geary wp/ / abstract: in a recent paper, kanazawa and kovar ( ) assert that given certain empirical regularities about assortative mating and the heritability of intelligence and beauty, that it logically follows that more intelligent people are more beautiful. it is argued here that this “theorem” is false and that the evidence does not support it. forthcoming in intelligence geary wp/ / introduction “inventing evolutionary stories is a seductively easy exercise” in kanazawa and kovar ( ) (henceforth kk) a remarkable assertion is made: given certain regularities about assortative mating and the heritability of intelligence and of beauty that it logically follows that beautiful people are more intelligent. they make four specific assumptions ( ) men who are more intelligent are more likely to attain high status than men who are less intelligent, ( ) higher status men are more likely to mate with beautiful women than lower status men ( ) intelligence is heritable and ( ) beauty is heritable. it is asserted that this logically (their emphasis) implies a “theorem” that “more beautiful people are more intelligent than less beautiful people”. in this note i show that their summary of the evidence is misleading and some new evidence on the relationship between beauty and intelligence is provided, casting further doubt on their claim. whether a correlation between beauty and intelligence really follows from these assumptions is a matter for debate. in my opinion it does not since there are a number of reasonable counter-arguments. for example what constitutes “high status” changes over time as the environment changes: what was attractive or intelligent in a mate in the pleistocene may be very different from what is attractive now. indeed the models that posed for goya's or ruben’s nudes would probably not get a job in the st century modeling industry. the correlation of the genes associated with beauty and intelligence may be complicated if the individual genes are pleiotropic, that is they affect multiple phenotypic traits. finally while beauty is heritable it is not immutable as the large industry devoted to grooming and laland and brown ( ) p . geary wp/ / beautification practices testifies to. more intelligent people may be more likely to engage in such practices because they are wealthier. so while more intelligent people may or may not be more beautiful they can generally avoid being slovenly or dirty. depending on whether kk’s argument is ceteris paribus or not (which is unclear) a positive correlation between beauty and intelligence is simply one possibility. why the evidence does not support it kk discuss a large literature analysing assumptions ( ) to ( ) and it seems plausible that these assumptions are a good summary of the data. five studies are cited which, it is claimed, compare intelligence and beauty and find the expected positive relationship. there may, of course, be other models which generate the same prediction . the cited paper by furlow et al ( ) is not about beauty or attractiveness (it mentions neither) but is about the relationship between intelligence and fluctuating asymmetry (fa). fa refers here to bilateral asymmetries in morphology e.g. differences in the sizes of one’s ears, digits etc. fa is likely to be inversely correlated with beauty but so too are a lot of factors. as the authors acknowledge, the observed correlations are modest in size. the explanations they offer for these correlations owe nothing to evolutionary arguments but point to the existence of some common physiological cause such as the effects of stress during early development. this interpretation is supported by bates ( ) who also finds a negative relationship between fa and intelligence with essentially the same explanation: that it reflects fitness related biological and psychological variation. the cited meta-analysis by jackson et al ( ) concludes that “…physical attractiveness was unrelated to actual intellectual competence in adults but was related for example the “good genes” explanation that there are genes which encode for both iq and attractiveness, see zebrowitz et al ( ) . geary wp/ / modestly in children” (p ). this is qualified by the fact that “actual intellectual competence” here includes direct measures as well as indirect measures such as competence in a particular occupation. the majority of studies ( of ) are for such indirect measures. the authors find a negative but statistically insignificant relationship for the direct measures. the cited meta-analysis by langlois et al ( ) also finds much smaller effect sizes for adults than children and concludes that attractive adults are “very slightly more intelligent” (p ) than unattractive adults. the cited paper by elder ( ) is based on undergraduates in oakland, california, so it is doubtful whether one can extrapolate to a wider population. a third meta-analysis, not cited by kk, feingold ( ) finds no evidence that more attractive adults were more intelligent. if a positive correlation between beauty and intelligence really is a logical implication of assumptions ( ) to ( ) then one would expect it to be found in all studies which is clearly not the case. a number of other papers are discussed by kk which, it is claimed, “indirectly demonstrate that the beautiful are more intelligent” (p ). there is no basis for this inference since these look at correlations between beauty and a range of other variables which may or may not be correlated with intelligence (such as income) but will also be correlated with other variables. the cited paper by hamermesh and biddle ( ) finds a positive relationship between attractiveness and earnings but there could be numerous causes for this and one cannot assume that it is acting as a proxy for intelligence. for example, an individual’s perceived beauty may be correlated with their self-esteem or their height and these can have independent effects on earnings . they do not mention intelligence as a factor and find strongest support for discrimination by the employer on the basis of taste. harper ( ) finds see bowles, gintis and osborne ( ) for example. mobius and rosenblatt ( ) o show that more attractive workers have greater self-confidence and hence higher wages. geary wp/ / an effect of beauty on earnings while controlling for cognitive ability. in summary, the existing evidence is weak and inconclusive on the correlation between beauty and intelligence. to examine this issue further, the british national child development survey (ncds) is used to further explore the relationship between intelligence and being attractive. the ncds is a cohort study of children born in one week in . at age their teacher was asked about the appearance of the child. there were possible answers and only the first two are used: attractive and not attractive. the three responses not used are being undernourished, abnormal and scruffy/dirty account for about % of the observations. intelligence is based on tests of verbal and non-verbal ability, mathematics and reading comprehension taken at age . the first principal component of these is used as a general measure of intelligence. this variable is labelled “iq” and is normalized to have a mean of and a standard deviation of . a probit model is used to estimate the probability of being deemed beautiful as a quadratic function of iq. higher order terms are redundant. figure graphs the predicted probability of being attractive against intelligence along with confidence bands. the relationship between intelligence and being attractive is generally positive but highly non- linear with the positive association diminishing at medium levels of intelligence and flattening out for much of the distribution of intelligence there is no significant relationship between being attractive and intelligence. since the evidence here suggests, if anything, that is primarily low intelligence that is associated with lack of beauty, it is worth asking whether there are alternative explanations for this. one possibility is that there are several syndromes that are associated with both low intelligence and some facial or other physical abnormality. down’s syndrome is probably the best known of these but there are several others including prader-willi syndrome, and turner’s geary wp/ / syndrome. given that these syndromes are rare it is doubtful if this could explain the results presented in figure or indeed any population survey. down’s syndrome is the most common one mentioned and one would not expect there to be more than about cases in the sample. the ncds recorded whether (according to a doctor) individuals were mentally retarded at age . if one eliminates from the sample those for whom there is some retardation ( out of ) the graph is not noticeably different while this test is not conclusive it suggests that it is not those with very low cognitive ability that are driving the results and one needs to look elsewhere for an explanation for the graph. it is possible that there is a “halo effect” i.e. that teachers will rate more intelligent people as being more attractive as they are less likely to be badly behaved etc. finally there is the point made in the previous section that the more intelligent may simply be better at avoiding being slovenly and unclean. conclusion measuring intelligence and its correlates is a fundamental research endeavour in psychology which has attracted huge interest and no little controversy amongst scholars. it is vital therefore that claims about the relationship between intelligence and other variables are carefully established. this paper argues that kk’s claim is theoretically suspect and that the evidence that is claimed to support it is, in fact, weak and inconclusive. geary wp/ / . . . . . intelligence pr e d ic te d pr o ba b ili ty figure : attractiveness age and intelligence note: % confidence bands. geary wp/ / references bates t.c. ( ) fluctuating asymmetry and intelligence, intelligence, , - bowles s., gintis h. & osborne m.( ). the determinants of earnings: a behavioural approach. journal of economic literature, xxxix, ( ) - feingold, a. ( ) attractive people are not what we think they are. psychological bulletin, , - . elder g.h. ( ). appearance and education in marriage mobility. american sociological review, , - . furlow, f.b., armijo-prewit, t. gangestad, s.w. & thornhill, t. ( ) fluctuating asymmetry and psychometric intelligence. proceedings of the royal society. series b: biological sciences, , - . hamermesh d. & biddle j.( ). beauty and the labor market, american economic review ( ) - . harper, b.( ). beauty, stature and the labour market: a cohort study, oxford bulletin of economics and statistics, ( ) , - jackson, l.a., hunter j.e. & hodge c.n. ( ). physical attractiveness and intellectual competence: a meta-analytic review. social psychology quarterly, , - . kanazawa, s. & kovar, j.l.( ). why beautiful people are more intelligent, intelligence, , - laland k.n. & g.r. brown ( ) sense and nonsense: evolutionary perspectives on human behaviour. oxford: oxford university press geary wp/ / langlois, j.h., kalakanis,l., rubenstein, a.j., larson,a.,hallam,m. & smoot,m.( ) maxims or myths of beauty? a meta-analytic and theoretical review, psychological bulletin, , - mobius m.m. & t.s. rosenblat ( ) why beauty matters, american economic review, ( ), - zebrowitz l.a., hall j.a., murphy n.a. & rhodes g. ( ) looking smart and looking good: facial cues to intelligence and their origins, personality and social psychology bulletin, ( ), - can we measure beauty? computational evaluation of coral reef aesthetics uva-dare is a service provided by the library of the university of amsterdam (https://dare.uva.nl) uva-dare (digital academic repository) can we measure beauty? computational evaluation of coral reef aesthetics haas, a.f.; guibert, m.; foerschner, a.; co, t.; calhoun, s.; george, e.; hatay, m.; dinsdale, e.; sandin, s.a.; smith, j.e.; vermeij, m.j.a.; felts, b.; dustan, p.; salamon, p.; rohwer, f. doi . /peerj. publication date document version final published version published in peerj license cc by link to publication citation for published version (apa): haas, a. f., guibert, m., foerschner, a., co, t., calhoun, s., george, e., hatay, m., dinsdale, e., sandin, s. a., smith, j. e., vermeij, m. j. a., felts, b., dustan, p., salamon, p., & rohwer, f. ( ). can we measure beauty? computational evaluation of coral reef aesthetics. peerj, , [e ]. https://doi.org/ . /peerj. general rights it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like creative commons). disclaimer/complaints regulations if you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the library know, stating your reasons. in case of a legitimate complaint, the library will make the material inaccessible and/or remove it from the website. please ask the library: https://uba.uva.nl/en/contact, or a letter to: library of the university of amsterdam, secretariat, singel , wp amsterdam, the netherlands. you will be contacted as soon as possible. download date: apr https://doi.org/ . /peerj. https://dare.uva.nl/personal/pure/en/publications/can-we-measure-beauty-computational-evaluation-of-coral-reef-aesthetics( c ea-bd f- - ed- c bb c ef).html https://doi.org/ . /peerj. submitted july accepted october published november corresponding author andreas f. haas, andreas.florian.haas@gmail.com academic editor robert costanza additional information and declarations can be found on page doi . /peerj. copyright haas et al. distributed under creative commons cc-by . open access can we measure beauty? computational evaluation of coral reef aesthetics andreas f. haas , marine guibert , anja foerschner , tim co , sandi calhoun , emma george , mark hatay , elizabeth dinsdale , stuart a. sandin , jennifer e. smith , mark j.a. vermeij , , ben felts , phillip dustan , peter salamon and forest rohwer department of biology, san diego state university, san diego, ca, united states ensta-paristech, université de paris-saclay, palaiseau, france the getty research institute, getty center, los angeles, ca, united states department of mathematics and statistics, san diego state university, san diego, ca, united states scripps institution of oceanography, university of california san diego, san diego, ca, united states caribbean research and management of biodiversity (carmabi), willemstad, curacao aquatic microbiology, university of amsterdam, amsterdam, netherlands department of biology, college of charleston, charleston, sc, united states abstract the natural beauty of coral reefs attracts millions of tourists worldwide resulting in substantial revenues for the adjoining economies. although their visual appearance is a pivotal factor attracting humans to coral reefs current monitoring protocols exclusively target biogeochemical parameters, neglecting changes in their aesthetic appearance. here we introduce a standardized computational approach to assess coral reef environments based on visual features designed to evaluate the aesthetic appearance of art. the main feature groups include color intensity and diversity of the image, relative size, color, and distribution of discernable objects within the image, and texture. specific coral reef aesthetic values combining all features were calibrated against an established biogeochemical assessment (nceas) using machine learning algorithms. these values were generated for ∼ , random photographic images collected from coral reef locations exposed to varying levels of anthropogenic influence across ocean systems. aesthetic values proved accurate predictors of the nceas scores (root mean square error < for n ≥ ) and significantly correlated to microbial abundance at each site. this shows that mathematical approaches designed to assess the aesthetic appearance of photographic images can be used as an inexpensive monitoring tool for coral reef ecosystems. it further suggests that human perception of aesthetics is not purely subjective but influenced by inherent reactions towards measurable visual cues. by quantifying aesthetic features of coral reef systems this method provides a cost efficient monitoring tool that targets one of the most important socioeconomic values of coral reefs directly tied to revenue for its local population. subjects environmental sciences, computational science keywords image analysis, coral reef, aesthetics, machine learning, reef degradation how to cite this article haas et al. ( ), can we measure beauty? computational evaluation of coral reef aesthetics. peerj :e ; doi . /peerj. mailto:andreas.florian.haas@gmail.com https://peerj.com/academic-boards/editors/ https://peerj.com/academic-boards/editors/ http://dx.doi.org/ . /peerj. http://dx.doi.org/ . /peerj. http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / https://peerj.com http://dx.doi.org/ . /peerj. introduction together with fishing, cargo shipping, and mining of natural resources, tourism is one of the main economic values to inhabitants of coastal areas. tourism is one of the world’s largest businesses (miller & auyong, ) and with ecotourism as the fastest growing form of it worldwide (hawkins & lamoureux, ) the industry is increasingly dependent on the presence of healthy looking marine ecosystems (peterson & lubchenco, ). in this context coral reefs are one of the most valuable coastal ecosystems. they attract millions of visitors each year through their display of biodiversity, their abundance of colors, and their sheer beauty and lie at the foundation of the growing tourism based economies of many small island developing states (neto, ; cesar, burke & pet-soede, ). over the past decades the problem of coral reef degradation as a result of direct and indirect anthropogenic influences has been rigorously quantified (pandolfi et al., ). this degradation affects not only the water quality, but also the abundance and diversity of the reefs inhabitants, like colorful reef fish and scleractinian corals. to assess the status of reef communities and to monitor changes in their composition through time, a multitude of monitoring programs have been established, assessing biophysical parameters such as temperature, water quality, benthic cover, and fish community composition (e.g., jokiel et al., ; halpern et al., ; kaufman et al., ). these surveys however target exclusively on provisioning, habitat, and regulating ecosystem services and neglect their cultural services; i.e., the immediately nonmaterial benefits people gain from ecosystems (seppelt et al., ; martin-lopez et al., ; casalegno et al., ). monitoring protocols to assess the biogeochemical parameters of an ecosystem, which need to be conducted by trained specialists to provide reliable data, will not give account of one of the most valuable properties of coastal environments: their aesthetic appearance to humans, which is likely the main factor prompting millions of tourists each year to visit these environments. the value of human aesthetic appreciation for ecosystems has been studied in some terrestrial (e.g., hoffman & palmer, ; van den berg, vlek & coeterier, ; sheppard, ; beza, ; de pinho et al., ) and marine ecosystems (fenton & syme, ; fenton, young & johnson, ; dinsdale & fenton, ). however most of these studies have relied on surveys, collecting individual opinions on the aesthetic appearance of specific animals or landscapes and are therefore hard to reproduce in other locations due to a lack of objective and generalizable assessments of aesthetic properties. a recent approach by casalegno et al. ( ) objectively measures the perceived aesthetic value of ecosystems by quantifying geo-tagged digital photographs uploaded to social media resources. although relatively new in the context of ecosystem evaluation, efforts to define uni- versally valid criteria for aesthetic principles have been existing since antiquity (e.g., plato, aristotle, confucius, laozi). alexander gottlieb baumgarten introduced aesthetics in as a philosophical discipline in his meditationes (baumgarten & baumgarten, ) and defined it as the science of sensual cognition. classicist philosophers such as immanuel kant, georg wilhelm friedrich hegel, or friedrich schiller, then established further theories of the “aesthetic,” coining its meaning as a sense of beauty and connecting it to the visual arts. kant ( ) also classified judgments about aesthetic values as having a haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. subjective generality. in the th and st century, when beauty was not necessarily the primary sign of quality of an artwork anymore, definitions of aesthetics and attempts to quantify aesthetic values have reemerged as a topic of interest for philosophers, art historians, and mathematicians alike (e.g., datta et al., ; onians, ). with the term aesthetics recipients usually characterize the beauty and pleasantness of a given object (dutton, ). there are however various ways in which aesthetics is defined by different people as focus of interest and aesthetic values may change depending on previous attainment (datta et al., ). for example, while some people may simply judge an image by the pleasantness to the eye, another artist or professional photographer may be looking at the composition of the object, the use of colors and light, or potential additional meanings conveyed by the motive (datta et al., ). thus assessing the aesthetic visual quality of paintings seems, at first, to pose a highly subjective task (li & chen, ). contrary to these assumptions, various studies successfully applied mathematical approaches to determine the aesthetic values of artworks such as sculptures, paintings, or photographic images (datta et al., ; li & chen, ; ke, tang & jing, ). the methods used are based on the fact that certain objects or certain features in them have higher aesthetic quality than others (datta et al., ; li & chen, ). the overarching consensus hereby is that objects, or images, which are pleasing to the eye, are considered to be of higher value in terms of their aesthetic beauty. the studies which inspired the metrics used in our current work successfully extracted distinct features based on the intuition that they can discriminate between aesthetically pleasing and displeasing images. by constructing high level semantic features for quality assessment these studies have established a significant correlation between various computational properties of photographic images and their aesthetics perceptions by humans (datta et al., ; li & chen, ). methods study sites: four atolls across a gradient of human impact served as basis for this study. the islands are part of the northern line islands group located in the central pacific. the most northern atoll kingman has no population and is, together with palmyra which is exposed to sparse human impact, part of the us national refuge system. the remaining two atolls tabuaeran and kiritimati are inhabited and part of the republic of kiribati (dinsdale et al., ; sandin et al., ). to extend the validity of the method proposed here to other island chains and ocean systems we included an additional sampling site in the central pacific (ant atoll) and four locations in the caribbean also subjected to different levels of human impact ( sites on curacao, klein curacao, and barbuda, fig. ). from every location we collected sets of ± benthic photo-quadrant (preskitt, vroom & smith, ) and ± random pictures. to evaluate the level of human impact and status of the ecosystem we used the cumulative global human impact map generated by the national center for ecological analysis and synthesis (nceas; http://www.nceas.ucsb. edu/globalmarine/impacts). these scores incorporate data related to: artisanal fishing; demersal destructive fishing; demersal non-destructive, high-bycatch fishing; demersal haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://www.nceas.ucsb.edu/globalmarine/impacts http://dx.doi.org/ . /peerj. figure map of sampling sites with representative images and nceas scores. the upper images show images of the benthic community in the respective caribbean sites, the lower images represent the sampling sites throughout the tropical pacific. non-destructive low-bycatch fishing; inorganic pollution; invasive species; nutrient input; ocean acidification; benthic structures; organic pollution; pelagic high-bycatch fishing; pelagic low-bycatch fishing; population pressure; commercial activity; and anomalies in sea surface temperature and ultraviolet insolation (halpern et al., ; mcdole et al., ). additionally, bacterial cell abundance across the northern line islands and of the caribbean locations (curacao main island and barbuda; table ) were measured after the method described by haas et al. ( ). aesthetic feature extraction: in total we extracted, modified, and complemented features (denoted as f ,f , ...,f ) from three of the most comprehensive studies on computational approaches to aesthetically evaluate paintings and pictures (table s ; datta et al., ; li & chen, ; ke, tang & jing, ). aesthetic evaluation of paintings and photographs in all three studies were based on surveys of randomly selected peer groups. some of the features presented in previous work were however difficult to reproduce owing to insufficient information given on these features (e.g., f – , or f ). this may have led to slight alterations in some of the codes which were inspired by the suggested features but deviate slightly in their final form. as the pictures were considered to be objective samples representing the respective seascape, some traditional aesthetic features, like size of an image or its aspect ratio have not been considered in this study. overarching feature groups considered in the picture analysis were color, texture, regularity of shapes, and relative sizes and positions of objects in each picture. haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. aesthetic value: although some of the implemented codes appeared similar and were assessing closely related visual aspects, all of the suggested codes were implemented and their value, or potential redundancy, was evaluated using machine learning algorithms. following feature extraction the feature values were used as input for feed forward neural networks that optimize the importance of features or feature groups and generate a single aesthetic value for each respective photograph. the target outputs for the training of the networks were the nceas scores of the regions where the pictures were taken. the pictures were randomly separated into a batch used for training the machine learning algorithms (n = , ) and one on which the algorithms were tested (n = , from each of sites). we used matlab’s neural network package on the training samples which further subdivided these samples into training ( %), validation ( %) and test ( %) sets (see appendix for details). unlike previous studies in which the aesthetic quality was classified in given categories, this machine learning regression approach generates a continuous metric for the aesthetic quality of a given reefscape. results an aesthetic value of coral reef images was defined using features previously created for measuring the aesthetic quality of images. the values were calibrated using machine learning to match nceas scores as closely as possible. our algorithm gleaned the nceas score from an image to within a root mean squared (rms) error of . . using five images from the same locale improved the nceas score prediction to an rms error of . . the relative importance for each feature derived from a random forests approach showed that all three overarching feature groups, texture, color of the whole image, and the size, color, and distribution of objects within an image yielded important information for the algorithm (fig. s ). the ten most important features, or feature groups were hereby the similarity in spatial distribution of high frequency edges, the wavelet features, number of color based cluster, the area of bounding boxes containing a given percentage of the edge energy, the average value of the hsv color space, entropy of the blue matrix, range of texture, the arithmetic and the logarithmic average of brightness, and the brightness of the focus region as defined by the rule of thirds. the mean coral reef aesthetic values generated with this approach for each picture were significantly different (p < . ) between all sampling locations except for ant atoll, fanning and klein curacao (anova followed by tukey, see table s ). these sites are also exposed to comparable levels of anthropogenic disturbance (nceas: . – . ). regression of coral reef aesthetic values against the nceas scores of the respective sampling site showed a significant correlation (p < . ) for both the training (n = , , r = . ) and the test (n = , r = . ) set of images (fig. ). further comparison to microbial abundance, available for of the locations (microbial numbers for curacao buoy and ant atoll were not available), revealed a significant correlation between the aesthetic appearance of the sampling sites and their microbial density (p = . , r = . ; fig. ). haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. figure coral reef aesthetic values. boxplots of coral reef aesthetic values at each site and regression of coral reef aesthetic values vs. nceas scores across all assessed reef sites. (test) shows coral reef aesthetic values calculated for images on which the previously trained machine learning algorithm was tested. (training) shows the generated coral reef aesthetic values from , images used to improve the feed forward neural networks that optimized the importance of features or feature groups in generating a single coral reef aesthetic value. discussion this is the first study using standardized computational approaches to establish a site-specific correlation between aesthetic value, ecosystem degradation, and the microbialization (mcdole et al., ) of marine coral reef environments. human response to visual cues the connection between reef degradation and loss of aesthetic value for humans seems intuitive but initially hard to capture with objective mathematical approaches. dinsdale ( ) showed that human visual evaluations provided consistent judgment of coral reef status regardless of their previous knowledge or exposure to these particular ecosystems. the most important cue was the perceived health status of the system. crucial for this intuitive human response to degraded or “unhealthy” ecosystems is the fact that we are looking at organic organisms and react to them with the biological innate emotion of disgust (curtis, ; hertz, ). being disgusted is a genetically anchored reaction to an object or situation, which might be potentially harmful to our system. often, a lack of salubriousness of an object or situation is the crucial element for our senses, one of them visual perception, to signal us to avoid an object or withdraw from a situation (foerschner, ). as the microbial density and the abundance of potential pathogens in degrading reefs are significantly elevated (dinsdale et al., )—albeit not visible haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. figure distribution of aesthetic values. (a) shows microbial cell abundance at reef sites. (b) shows the distribution of pictures with respective aesthetic values at each of those sites. (c) shows the regression between mean microbial cell abundance and mean aesthetic value (training + test) across all sampling sites. to the human eye—our inherent human evaluation of degraded reefs as aesthetically unpleasing, or even disgusting, is nothing else than recognizing the visual effects of these changes as a potential threat for our well-being. generally the emotion of disgust protects the boundaries of the human body and prevents potentially harmful substances from compromising the body. this theory was supported by french physiologist richet ( ), who described disgust as an involuntary and hereditary emotion for self-protection. the recognition of something disgusting, and thus of a lack of aesthetic value, prompts an intuitive withdrawal from the situation or from the environment triggering this emotion. recent evolutionary psychology largely follows this thesis and concludes that disgust, even though highly determined by a certain social and cultural environment, is genetically imprinted and triggered on a biological level by objects or environments which are unhealthy, infectious, or pose a risk to the human wellbeing (rozin & fallon, ; rozin & schull, ; foerschner, ). decisive here is the connection between disgust and the salubriousness, or better lack thereof, of given objects, which indicates unhealthiness. our here presented study supports these theories by establishing objectively quantifiable coral haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. reef aesthetic values for ecosystems along a gradient of reef degradation, and for a subset microbial abundance. perception of aesthetic properties is not purely a subjective task and measurable features of aesthetic perception are inherent to human nature. the main visual features assessed by our analysis are color intensity and diversity, relative size and distribution of discernable objects, and texture (fig. s and table s ). human perception of each of these features does not only trigger innate emotions, each of these features also yields palpable information on the status of the respective ecosystem. color: thriving ecosystems are abounding with bright colors. on land photosyn- thesizing plants display a lush green and, at least seasonally, blossoms and fruits in every color. animals display color for various reasons, for protective and aggressive resemblance, protective and aggressive mimicry, warning colors, and colors displayed in courtship (cope, ). underwater, coral reefs surpass all other ecosystems in their display of color. the diversity and colorfulness of fauna and flora living in healthy reef systems is unmatched on this planet (marshall, ; kaufman, ). this diverse and intense display of color is, however, not only an indicator of high biodiversity, but also of a “clean” system. the brightest and most diverse display of colors by its inhabitants will be dampened in a system with foggy air or murky waters. previous studies suggest an evolutionary theory in the human preference of color patterns as a result of behavioral adaptations. hurlbert & ling ( ) conclude that color preferences are engrained into human perception as neural response to selection processes improving performance on evolutionarily important behavioral tasks. humans were more likely to survive and reproduce successfully if they recognize objects or environments that characteristically have colors which are advantageous/disadvantageous to the organism’s survival, reproductive success, and general well-being (palmer & schloss, ). thus it is again not surprising that humans are inherently drawn to places with bright and diverse colors as they represent clean systems not associated with pollution or other health risks. objects: not only does the visual brain recognize properties like luminance or color, it also segregates higher-order objects (chatterjee, ). the relative size, distribution and regularity of objects in the pictures analyzed were important features in determining the aesthetic value of pictures. birkhoff ( ) proposed in his theory of preference for abstract polygon shapes that aesthetic preference varies directly related to the number of elements. further it has been established that people tend to prefer round regular and convex shapes as they are more symmetrical and structured (jacobsen & höfel, ; palmer & griscom, ). the fluency theory provides an additional explanation for a general aesthetic preference for specific objects (reber, winkielman & schwarz, ; reber, schwarz & winkielman, ; reber, ). it predicts aesthetic inclination as a result of many low-level features (oppenheimer & frank, ), like preferences for larger (silvera, josephs & giesler, ), more symmetrical (jacobsen & höfel, ), more contrastive objects (reber, winkielman & schwarz, ; reviewed in reber, schwarz & winkielman, ). from a biological view there may be additional causes for the preference of larger discernable objects. bigger objects representing living entities indicate that the environment is suitable for large animals and can provide a livelihood for apex predators haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. like humans, while small objects suggest a heavily disturbed system, unable to offer resources for growth or a long life experience for its inhabitants. the lack of discernable objects like fish, hard corals, or giant clams suggests that microbiota are dominant in this system, likely at the expense of the macrobes (mcdole et al., ). texture: another important criterion in the aesthetic evaluation of an image is the existence of clearly discernible outlines; a distinguishable boundary texture that keeps objects separated from their environment. the russian philosopher bakhtin ( ) elevated this characteristic to be the main attribute of grotesqueness in relation to animated bodies. anything that disrupts the outline, all orifices or products of inner, bodily processes such as mucus, saliva, or semen evokes a negative emotional response of disgust and repulsion (foerschner, ; foerschner, ). even though various theories on triggers for disgust exist, the absence of discernable boundaries (both physical and psychological) are fundamental to all of them (foerschner, ; menninghaus, ). for living organisms the transgression of boundaries and the dissolution of a discernable surface texture signify much more than the mere loss of form: it comprehends the organism in a state of becoming and passing, ultimately in its mortality. decomposition, disease, and decay are as disgust- ing to us as mucus, saliva, or slime; the former in their direct relation to death, the latter ones as products of bodily functions, which equally identifies our organic state as transient (kolnai, ). further, amorphous slime covering and obscuring the underlying texture of objects may be the result of biofilm formation. a biofilm is a group of microorganisms which, frequently embedded within a mucoidal matrix, adheres to various surfaces. these microbial assemblages are involved in a wide variety of microbial infections (costerton, stewart & greenberg, ). human perception is therefore more likely to evaluate a vis- cous, slimy, or amorphous object surface as repulsive whereas surface textures with clearly defined boundaries and patterns are pleasing to our senses and generally deemed aesthetic. it has to be mentioned that by no means do we claim to provide an assessment for the value of art or artistic images by this method. the value of an artwork depends not only on the aesthetics, but also on the social, economic, political or other meanings it conveys (adorno, ), and on the emotions and impulses it triggers in a recipient. however this study suggests that perception of aesthetic properties may be more objective than com- monly appraised and patterns of aesthetic evaluation are inherent to human perception. crowd sourcing & historic data mining the approach provided here will likely be a valuable tool to generate assessments on the status of reef ecosystems, unbiased by the respective data originator. by taking a set of random photographic images from a given system information on the aesthetic value and thus on the status of the ecosystem can be generated. contrary to all previously introduced monitoring protocols the objective analysis of pictures will overcome bias introduced by the individual taking samples or analyzing the respective data. obviously, the analysis of a single picture will depend on the motive chosen or camera handling and not every single picture will accurately reflect the status of the ecosystem (fig. ). however, as in most ecological approaches the accuracy of the information increases with haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. figure image examples. examples of pictures with their respective generated aesthetic values from two contrasting sampling sites, kingman and kiritimati. aesthetic values for (a) and (b), which resemble representative images of the specific locations, were close matches to the nceas score at the respective site. (c) and (d) give examples of pictures which resulted in mismatches to the respective nceas score. sample size, i.e., number of digital images available (see fig. b). the application of this method to resources like geo-tagged digital image databases or historic images of known spatial and temporal origin will allow access to an immense number of samples and could provide objective information on the status and the trajectories of reefs around the world. previous studies already focused on the problem of establishing a baseline for pristine marine ecosystems, especially coral reefs. but coral reefs are among the most severely impacted systems on our planet (knowlton, ; wilkinson, ; bellwood et al., ; pandolfi et al., ; hoegh-guldberg et al., ) and most of the world’s tropical coastal environments are so heavily degraded that pristine reefs are essentially gone (jackson et al., ; knowlton & jackson, ). the here presented method could provide a tool to establish a global baseline of coral reef environments, dating back to the first photographic coverage of the respective reef systems. as an example we used photographic images of the haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. a) carysfort reef : . b) carysfort reef : . c) carysfort reef : . d) carysfort reef : . e) carysfort reef : . f) palmyra : . figure aesthetic values of carysfort reef. (a–e) are taken at the identical location on carysfort reef, us caribbean, over a time span of years (photos taken by p dustan). the aesthetic value calculated for each picture shows a significant degradation of aesthetic appearance during this period. the historic images from indicate that the aesthetic appearance of this caribbean reef was comparable to present day pristine reefscapes as for example on palmyra atoll in the central pacific (f, photo taken by j smith). carysfort reef in the us caribbean, taken at the same location over a time span of nearly years ( – ). the image analysis showed a clear degradation of aesthetic values during those four decades (fig. ). while the aesthetic appearance of this caribbean reef in is comparable to reefscapes as they are found on remote places like the palmyra atoll today, the aesthetic value drastically declined over the year time span and place the aesthetic appearance of this reef below the heavily degraded reef sites of kiritimati today ( and ). socioeconomic assessment for stakeholders this study provides an innovative method to objectively assess parameters associated with a general aesthetic perception of marine environments. although converting the aesthetic appearance of an entire ecosystem in simple numbers will likely evoke discussions and in some cases resentment, it may provide a powerful tool to disclose effects of implementing haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. conservation measurements on the touristic attractiveness of coastal environments to stakeholders. the approach allows for a rapid analysis of a large number of samples and thus provides a method to cover ecosystems on large scale. linking aesthetic values to cultural benefits and ultimately revenue for the entire community may be an incentive to further establish and implement protection measurements and could help to evaluate the success and the value to the community of existing conservation efforts. using monitoring cues that directly address inherent human emotions will more likely motivate and sustain changes in attitude and behavior towards a more sustainable usage of the environmental resources than technical terms and data that carry no local meaning (carr, ; dinsdale, ). quantifying the aesthetic appearance of these ecosystems targets on one of the most important socioeconomic values of these ecosystems, which are directly tied to culture and the revenue of its local population. acknowledgements we thank the biosphere foundation for providing the pictures of carysfort reef. we further thank the captain, martin graser, and crew of the m/y hanse explorer. appendix: feature extraction global features global features are computed over all the pixels of an entire image. color: the hsl (hue, saturation, lightness) and hsv (hue, saturation, value) color spaces are the two most common cylindrical-coordinate representations of points in an rgb color model. the hsv and hsl color space define pixel color by its hue, saturation and value, respectively lightness (joblove & greenberg, ). this provides a color definition similar to the human visual perception. the first step for each picture analysis was therefore to calculate the average hue, saturation and value respectively lightness for both color spaces. assuming a constant hue, the definition of saturation and of value and lightness are very much different. therefore hue, saturation, and value of a pixel in the hsv space will be denoted as ih (m,n),is(m,n) and iv (m,n), and hue, saturation and lightness in the hsl space as ih (m,n), is (m,n) and il (m,n) from here on, where m and n are the number of rows and columns in each image. f = mn  n  m ih (m,n) ( ) f = mn  n  m is(m,n) ( ) f = mn  n  m iv (m,n) ( ) f = mn  n  m is (m,n) ( ) f = mn  n  m il (m,n). ( ) haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. to assess colorfulness the rgb color space was separated in cubes of identical volume by dividing each axis in four equal parts. each cube was then considered as individual sample point and color distribution d of each image defined as the frequency of color occurrence within each of the cubes. additionally a reference distribution d was generated so that each sample point had a frequency of / . the colorfulness of an image was then defined as distance between these two distributions, using the quadratic-form distance (ke, tang & jing, ) and the earth mover’s distance (emd). both features take the pair-wise euclidian distances between the sample points into account. assuming ci is now the center position of the i-th cube, we get dij = ∥rgb luv(ci) − rgb luv(cj)∥ after a conversion to the luv (adams chromatic valence space; adams, ) color space. this leads to f =  h − h  t a  h − h  and f = emd(d ,d ,{dij| < i,j < }) ( ) in which h and h are vectors listing the frequencies of color occurrence in d and d . a = (aij) is a similarity matrix with aij = − dij/dmax and dmax = max(dij); ‘emd’ denotes the earth mover’s distance we implemented using an algorithm described by rubner, tomasi & guibas ( ). for color analysis only pixels with a saturation is (m,n) < . and a lightness il ∈ [ . , . ] were used as the human eye is unable to distinguish hues and only sees shades of grey outside this range. as ph = {(m ′,n′)|is > . and . < il < . } represents the set of pixels whose hues can be perceived by humans, f was defined as the most frequent hue in each image and f as the standard deviation of colorfulness. f = min(hmax), ( ) where ∀ hue h, # of {(m′,n′) ∈ ph |ih = hmax} ≥ # of {(m ′,n′)} ∈ ph |ih = h. if hues had an identical cardinal, the smallest one was chosen. f = std(var(i ′ h )). ( ) where i′h (m,n) = ih (m,n) if (m,n) ∈ ph ; otherwise i ′ h (m,n) = . var (i ′ h ) is the vector containing the variance of each column of i′h , and std returns its standard deviation. the hue interval [ , ] was then uniformly divided into bins of identical size and computed into a hue histogram of the image. q represents the maximum value this histogram and the hue count was defined as the number of bins containing values greater than c · q. the number of missing hues represents bins with values smaller than c · q. c and c was set to . and . , respectively. f = # of {i|h(i) > c · q} ( ) f = # of {i|h(i) < c · q}. ( ) hue contrast and missing hues contrast was computed as: f = max(∥ch(i) − ch(j)∥al) with i,j ∈ {i|h(i) > c · q} ( ) f = max(∥ch(i) − ch(j)∥al) with i,j ∈ {i|h(i) < c · q} ( ) haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. where ch(i) is the center hue of the i-th bin of the histogram and ∥ · ∥al refers to the arc-length distance on the hue wheel. f denotes the percentage of pixels belonging to the most frequent hue: f = q/n where n = # of ph ( ) f = − # of {i|h(i) > c · q} with c = . ( ) color models: as some color combinations are more pleasant for the human eye than others (li & chen, ), each image was fit against one of color models (fig. s k). as the models can rotate, the k-th model rotated with an angle α as mk(α), gk(ih (m,n) was assigned to the grey part of the respective model. emk (α)(m,n) was defined as the hue of gk(α) closest to ih . emk (α)(m,n) =  ih (m,n) if ih (m,n) ∈ gk(α) hnearestborder if ih (m,n) ∉ gk(α)  ( ) where hnearestborder is the hue of the sector border in mk(α) closest to the hue of pixel (m,n). now the distance between the image and the model mk(α) can be computed as fk,α =  m  m is (m,n)  n  m ∥emk(α)(m,n) − ih (m,n)∥al · is (m,n) ( ) with is (m,n) accounting for less color differences with lower saturation. this definition of the distance to a model was inspired by datta et al. ( ) with the addition of a normalization  m  n is (m,n) which allows for a comparison of different sized images. as the distances of an image to each model yield more information than the identity of the single model the image fits best, all distances were calculated and features f –f are therefore defined as the smallest distance to each model: f +k = min α fk,α, k ∈ { ,..., }. ( ) theoretically the best fitting hue model could be defined as mko(αo) with α(k) = arg min α fk,α,k = arg min k∈{ ,... } fk,α(k) and α = α(k ). ( ) those models are, however, very difficult to fit. therefore we set a threshold th assuming that if fk,α(k) < th, the picture fits the k-th color model. if ∀k fk,α(k) ≥ th the picture was fit to the closest model. in case several models could be assigned to an image not the closest one, but the most restrictive was chosen. as the color models are already ordered according to their restrictiveness the fit to the color model we characterize as: f =  maxk ∈ {j|fj,α(j),th} k if ∃k ∈ { ,..., },fk,α(k) < th k if ∀kfk,α(k) ≥ th  ( ) normalizing the distances to the models enabled us to set a unique threshold (th = ) for all the images independently of their size. haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. brightness: light conditions captured by a given picture are some of the most noticeable features involved in human aesthetic perception. some information about the light condition is already explored by the previously described color analysis, however, analyzing the brightness provides an even more direct approach to evaluating the light conditions of a given image. there are several ways to measure the brightness of an image. for this study, we implemented analysis which target slightly different brightness contrasts. f = mn  m  n l(m,n) ( ) f = exp  mn  m  n log  ∈ + l(m,n)  ( ) where l(m;n) = (ir(m;n) + ig (m;n) + ib(m;n))/ . f represents the arithmetic and f the logarithmic average brightness; the latter takes the dynamic range of the brightness into account. different images can therefore equal in one but differ in the other value. the contrast of brightness was assessed by defining h as a histogram with equally sized bins for brightness l(m;n), with d as index for the bin with the maximum energy h (d) = max(h ). two indices a and b were set as the interval [a;b] which contains % of the energy of h . the histogram was then analyzed step by step towards both sides starting from the dth bin to identify a and b. the first measure of the brightness contrast is then f = b − a + . ( ) for the second contrast quality feature a brightness histogram h with bins comprising the sum of the gray-level histograms hr,hg and hb generated from the red, green and blue channels: h (i) = hr(i) + hg (i) + hb(i), ∀i ∈ { ,..., }. ( ) the contrast quality f is then the width of the smallest interval [a ,b ] whereb i=a h (i) > .  i= h (i). f = b − a . ( ) edge features: edge repartition was assessed by looking for the smallest bounding box which contains a chosen percentage of the energy of the edges, and compare its area to the area of the entire picture. although li & chen ( ) and ke, tang & jing ( ) offer two different versions to target this feature, both use the absolute value of the output from a × laplacian filter with α = . . for color images the r, g and b channels are analyzed separately and the mean of the absolute values is used. at the boundaries the values outside the bounds of the matrix was considered equal to the nearest value in the matrix borders. according to li & chen ( ) the area of the smallest bounding box, containing % of the edge energy of their ‘laplacian image’ ( % in each direction), was divided by the area haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. of the entire image (figs. s e–s h). f = h w /hw ( ) h and w represent the height and width of the bounding box with h and w as the height and width of the image. ke, tang & jing ( ) resized each laplacian image initially to × and the image sum was normalized to . subsequently the area of the bounding box containing . % of the edge energy ( % in each direction) was established and the quality of the image was defined as − h w , whereby h and w are the height and width of the bounding box. f = − h w ;h and w ∈ [ , ]. ( ) resizing and normalizing the laplacian images further allows for an easy comparison of different laplacian images. analog to ke, tang & jing ( ) who compared one group of professional quality photos and one group of photos of inferior quality, we can now consider two groups of images: one with pictures of pristine and one with pictures of degraded reefs. mp and ms represent the mean laplacian image of the pictures in each of the respective groups. this allows a comparison of the laplacian image l with mp and ms using the l -distance. f = ds − dp, where ( ) ds =  m,n |l(m,n) − ms(m,n)| ( ) dp =  m,n |l(m,n) − mp(m,n)|. ( ) the sum of edges f was added as an additional feature not implemented by one of the above mentioned studies. sobel image s of a picture was defined as a binary image of identical size, with ’s assigned to edges present according to the sobel method and ’s for no edges present. for a color image sobel images sr,sg and sb were constructed for each of its red, green and blue channels and the sum of edges defined as f = (|sr|l + |sg |l + |sb|l )/ . ( ) texture analysis: to analyze the texture of pictures more thoroughly we implemented features not yet discussed in ke, tang & jing ( ), datta et al. ( ), or li & chen ( ). therefore we considered rh to be a matrix of the same size as ih , where each pixel (m,n) contains the range value (maximum value–minimum value) of the -by- neighborhood surrounding the corresponding pixel in ih . rs and rv were computed in the same way for is and iv and the range of texture was defined as f = mn  m  n (rh (m,n) + rs(m,n) + rv (m,n))/ . ( ) haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. additionally dh ,ds, and dv were set as the respective matrix identical in size to ih ,is, and iv , where each pixel (m,n) contains the standard deviation value of the -by- neighborhood around the corresponding pixel in ih ,is, or iv . the average standard deviation of texture was defined as: f = mn  m  n (dh (m,n) + ds(m,n) + dv (m,n))/ . ( ) the entropy of an image is a statistical measure of its randomness, and can also be used to characterize its texture. for a gray-level image, it is defined as—  i= p(i) ∗ log (p(i)) where p is a vector containing the bin gray-level histogram of the image. thus, we define features f , f and f as the entropy of ir , ig , and ib respectively. f = entropy (ir) ( ) f = entropy (ig ) ( ) f = entropy (ib). ( ) wavelet based texture: texture feature analysis based on wavelets was conducted according to datta et al. ( ). however concrete information on some of the implemented steps (e.g., norm or exact daubechies wavelet used) was sometimes not available which may result in a slight deviation of the calculation. first a three level wavelet transformation on ih was performed using the haar wavelet (see figs. s i and s j). a d wavelet transformation of an image yields matrices: the approximation coefficient matrix ca and the three details coefficient matrices ch ,cv and cd. height and width of resulting matrices are % of the input image and ch ,cv and cd show horizontal, vertical and diagonal details of the image. for a three-level wavelet transformation a d wavelet transformation is performed and repeated on the approximation coefficient matrix ca and repeated again on the new approximation coefficient matrix ca , resulting in sets of coefficients matrices. the ith-level detail coefficient matrices for the hue image ih were then denoted as chi ,c v i , and c d i (i ∈ { , , }). features f –f are then defined as follows: f +i = si  m  n (chi (m,n) + c v i (m,n) + c d i (m,n)), i ∈ { , , } ( ) where ∀i ∈ { , , }, si = |c h i |l + |c v i |l + |c d i |l . features f –f and f –f recomputed accordingly for is and iv. features f –f are defined as the sum of the three wavelet features for h,s, and v respectively: f =  i= fi,f =  i= fi,f =  i= fi. ( ) blur: measurements of the image blur were done based on suggestions given by li & chen ( ) and ke, tang & jing ( ). based on the information provided we were not able to implement the features successfully, thus the features presented here are a modified haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. adaptation. for this purpose each picture was considered to be a blurred image iblurred as a result of the convolution of an hypothetical sharp version of the image isharp and a gausssian filter gσ : iblurred = gσ ∗ isharp. as the gaussian filter eliminates high frequencies only, the blur of a picture can be determined by quantifying the frequency of the image above a certain threshold θ . a higher frequency indicates less blur. the threshold θ reduces the noise and provides a defined cutoff of the high frequencies. to quantify blur in a given image, a d fourrier transform was performed resulting in y . to avoid ambiguities the d fourrier transform is then normalized by / √ mn : y = fft (iblurred)/ √ mn . as we observed a phenomenon of spatial aliasing, only the frequencies (m′,n′) where < m′ < m/ and < n′ < n/ were used, resulting in f = max  m′ −  m  m ; n′ −  n  n  ( ) where |y (m′,n′)| > θ , < m′ < m/ , and < n′ < n/ . the threshold was set as θ = . . local features in addition to global features which provide information about the general aspect of a picture, local features consider fragments of the image. this approach focuses on objects captured in the photograph, while disregarding the overall composition, which is partly dependent on the camera operator. objects corresponding to uniform regions can be detected with the segmentation process described in datta et al. ( ). first the image is transformed in the luv color space and the k means algorithm is used to create k color-based pixel cluster. then a connected components analysis in an -connected neighborhood is performed to generating a list of all segments present. the largest segments are denoted as s ,...s , in decreasing order. as most pictures contain many details resulting in noise, we applied a uniform blur with m × m ones matrix as kernel before the segmentation process. rule of third: a well-known paradigm in photography is that the main subject of attention in a picture should generally be in its central area. this rule is called the ‘rule of third’ and the ‘central area’ can more precisely defined as the ninth of a photo divided by / and / of its height and width (see figs. s a and s b). using hsv color space f defines the average hue h for this region f =  m  −  m  +  n  −  n  +   m  m=  m   n  n=  n ih (m,n) ( ) is and iv are computed accordingly with f and f . focus region: li & chen ( ) offer a slightly different approach on the rule of thirds. the study suggests to use hsl color space and argue that focusing exclusively on the central ninth is too restrictive. from this approach, the focus region fr was defined as the central ninth of the respective picture haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. plus a defined percentage µ in its immediate surrounding (figs. s a and s b). for the here presented image analysis we set µ = . . f = #of{(m,n)|(m,n) ∈ fr}  (m,n)∈fr ih (m,n) ( ) is and il are computed accordingly with f and f . segmentation: the segmentation process generates a list l of connected segments in which the largest segments are denoted as s , . . . , s . our analysis focuses on the largest or segments only. not only were the properties of each of these segments, but also the quantity of the connected segments in each picture recorded. this provides a proxy for the number of objects and the complexity of each recorded image. f = # of l. ( ) the number of segments si in l above a certain threshold (f ), and the size of the largest segments si (f –f ) was defined as: f = # of {si|# of si < mn/ ,i ∈ { ,..., }} ( ) f +i = (# of si)/mn, ∀ ∈ { ,..., }. ( ) to gain information on the position of these biggest segments, the image was divided in equal parts identical to rule of third feature analysis. setting (ri,ci) ∈ { , , } as the indices of the row and column around the centroid of si, features f through f as were defined, starting on the top left of each image as f +i = ∗ r + c, ∀ ∈ { ,..., }. ( ) the average hue, saturation and value were then assessed for each of the objects. features f through f were computed as the average hues of each of the segments si, in the hsv color space: f +i = # of si  (m,n)∈si ih (m,n), ∀i ∈ { ,..., }. ( ) features f –f and f –f are computed analog for is and iv respectively. features f – f were further defined as the average brightness of the top segments: f +i = # of si  (m,n)∈si l(m,n), ∀i ∈ { , , } ( ) lightness l(m,n) has already been defined under ‘brightness analysis’. this allows us to compare the colors of each of the segments and to evaluate their diversity by measuring the average color spread f of their hues. as complementary colors are aesthetically more pleasing together f was defined as the average complementary colors among the assessed segments. haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. f =  i=  j= |h(i) − h(j)| and f =  i=  j= ∥h(i) − h(j)∥al ( ) where ∀i ∈ ,..., ,h(i) = f +i is the average hue of si. as round, regular and convex shapes are considered to be generally more beautiful, the presence of such shapes in a picture should increase its aesthetic value. here we only assessed the shapes of the largest segments in each image. the coordinates of the centers of mass (first-order moment), the variance (second-order centered moment) and skewness (third-order centered moment) was calculated for each of these segments was calculated by defining for all i ∈ { , , } f +i = xi = # of si  (m,n)∈si x(m,n) ( ) f +i = yi = # of si  (m,n)∈si y(m,n) ( ) f +i = # of si  (m,n)∈si ((x(m,n) − xi) + ((y(m,n) − yi) ) ( ) f +i = # of si  (m,n)∈si ((x(m,n) − xi) + ((y(m,n) − −yi) ) ( ) where ∀(m,n),(x(m,n),y(m,n)) are the normalized coordinates of pixel (m,n). horizontal and vertical coordinates were normalized by height and width of the image to account for different image ratios. to quantify convex shapes in an image f was defined as the percentage of image area covered by convex shapes. to reduce noise only r segments p ,...,pr containing more than mn/ pixels were incorporated in this feature. the convex hull gk was then computed for each pk. a perfectly convex shape pk ∩ gk = pk and area(pk) area(gk) = would be too restrictive for our purposes of analyzing natural objects, so pk was considered convex if area(pk) area(gk) > δ. f = mn r k= i  area(pk) area(gk) > δ  ∗ |area(pk)| ( ) where i(·) is the indicator function and δ = . . the last features using segmentation measure different types of contrast between the largest segments. features f –f address the hue contrast, the saturation contrast, the brightness contrast, and the blur contrast. first the average hue, saturation, brightness, and the blur for each si was calculated h(i) = # of si  (m,n)∈si ih (m,n), ∀i ∈ { ,..., } ( ) s(i) = # of si  (m,n)∈si is(m,n), ∀i ∈ { ,..., } ( ) haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. l(i) = # of si  (m,n)∈si l(m,n), ∀i ∈ { ,..., }. ( ) to calculate the blur of the segment si, isi was computed so that isi(m,n) =  (ir(m,n) + ir(m,n) + ir(m,n))/ if (m,n) ∈ si otherwise ( ) and b(i) defined as blur measure of isi for all i ∈ { ,..., } , analog to the previously described ‘blur measure’. b(i) = max  m′ −  m  m ; n′ −  n  n  ( ) where |yi(m ′,n′)| > θ, < m′ < m/ and < n′ < n/ , with yi = fft (isi)/ √ mn and θ = . . features f –f were then defined as f = max i,j∈{ ,..., } (∥ h(i) − h(j)∥al) ( ) f = max i,j∈{ ,..., } (∥ s(i) − s(j) ∥) ( ) f = max i,j∈{ ,..., } (∥ l(i) − l(j) ∥) ( ) f = max i,j∈{ ,..., } (∥ b(i) − b(j) ∥). ( ) low depth of field indicators: finally, according to the method described by datta et al. ( ) to detect low depth of field (dof) and macro images, we divided the images into rectangular blocks of identical size m , ..., m , numbered in row-major order. applying the notations of the ‘wavelet based texture’, ch ,c v , and c d denote the third level detail coefficient matrices generated by performing a three-level haar wavelet transform on the hue channel of the image. the low dof for the hue is then computed as f =  (m,n)∈m m m m (c h (m,n) + c v (m,n) + c d (m,n)) i=  (m,n)∈mi(c h (m,n) + c v (m,n) + c d (m,n)) ( ) and f and f are calculated similarly for saturation and value. machine learning to reduce the noise and decrease the error, we analyzed multiple methods of determining feature importance. an unsupervised random forests approach was used to identify the most important features (fig. s ). for every tree in the construction of a random forests, an out-of-bag sample was sent down the tree for calculation and the number of correct predictions was recorded. the variable importance was then generated by comparing the number of correct predictions from the out-of-bag sample to a randomly permuted haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. /supp- http://dx.doi.org/ . /peerj. variant. for each feature, the resulting importance is: ntrees  all trees (roob − rperm). a second method was to identify redundant columns before the training. using a covariance matrix of the features, relationships between columns were analyzed and columns with a correlation greater than . were clustered into groups. within every group, features were either directly or mutually related. in order to not compromise the comprehensive approach of the coral reef aesthetic feature analysis the most important features from each group remained in the analysis while highly correlated, less important features within a group were removed. we built neural networks based on these two methods and discerned when removing redundant features we obtained lower mean square errors. thus, we utilized a total of features when building our ensemble of neural networks. to fuse the predictive power of the aesthetic features, a levenberg–marquardt algorithm was used simultaneously on every sample of the training set to minimize the mean squared error of the estimated output score and the nceas value. typical mean squared error rates were in the s. we then decided on a threshold of for the mean squared error and searched the weight space of the neural network to find sets of weights with a mean squared error of less than on the validation set. the predicted nceas scores of these networks were then averaged for the ensemble prediction, which is our aesthetic value. after running test data through the ensemble of neural networks, we further analyze the accuracy of our system by simultaneously testing multiple pictures at a time. to see how much more reliably we could deduce the nceas score using n pictures from the same site, we averaged the outputs from our ensemble of neural networks for all twenty choose n (n = , , , , ) combinations available from the test batch. combinations of multiple pictures increased the accuracy of the root mean square error of . for n = – . for n = , . for n = , and . for both n = and n = . additional information and declarations funding the work was funded by the gordon and betty moore foundation, investigator award to fr. the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. grant disclosures the following grant information was disclosed by the authors: gordon and betty moore foundation: . competing interests the authors declare there are no competing interests. haas et al. ( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . /peerj. author contributions • andreas f. haas conceived and designed the experiments, performed the experiments, analyzed the data, wrote the paper, prepared figures and/or tables, reviewed drafts of the paper. • marine guibert, sandi calhoun and emma george performed the experiments, analyzed the data, prepared figures and/or tables, reviewed drafts of the paper. • anja foerschner conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, wrote the paper, reviewed drafts of the paper. • tim co performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, prepared figures and/or tables, reviewed drafts of the paper. • mark hatay and phillip dustan performed the experiments, contributed reagents/materials/analysis tools, prepared figures and/or tables, reviewed drafts of the paper. • elizabeth dinsdale conceived and designed the experiments, performed the experi- ments, contributed reagents/materials/analysis tools, wrote the paper, prepared figures and/or tables, reviewed drafts of the paper. • stuart a. sandin and jennifer e. smith performed the experiments, contributed reagents/materials/analysis tools, reviewed drafts of the paper. • mark j.a. vermeij performed the experiments, contributed reagents/materials/analysis tools, wrote the paper, reviewed drafts of the paper. • ben felts performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, reviewed drafts of the paper. • peter salamon conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, wrote the paper, prepared figures and/or tables, reviewed drafts of the paper. • forest rohwer conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, wrote the paper, reviewed drafts of the paper. supplemental information supplemental information for this article can be found online at http://dx.doi.org/ . /peerj. #supplemental-information. references adams eq. . chromatic valence as a correlate of munsell chroma. in: proceedings of the twenty-eighth annual meeting of the optical society of america, vol. . 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( ), peerj, doi . /peerj. / https://peerj.com http://dx.doi.org/ . / - . http://dx.doi.org/ . /s pspr _ http://dx.doi.org/ . / - x. . . http://dx.doi.org/ . /a: http://dx.doi.org/ . /journal.pone. http://dx.doi.org/ . /j. - . . .x http://dx.doi.org/ . /bdm. http://dx.doi.org/ . /jevp. . http://dx.doi.org/ . /peerj. can we measure beauty? computational evaluation of coral reef aesthetics introduction methods results discussion human response to visual cues crowd sourcing & historic data mining socioeconomic assessment for stakeholders acknowledgements appendix: feature extraction global features local features machine learning references a study of beauty baryons with extended local hidden gauge approach a study of beauty baryons with extended local hidden gauge approach c. w. xiaoa,∗, w. h. lianga,b, e. oseta adepartamento de fı́sica teórica and ific, centro mixto universidad de valencia-csic, institutos de investigación de paterna, apartado , valencia, spain bdepartment of physics, guangxi normal university, guilin, , p. r. china abstract in present work we investigate the interaction of b̄n, b̄Δ, b̄∗n and b̄∗Δ states, together with their coupled channels. taking into account the heavy quark spin symmetry for pion exchange and the results of the weinberg tomozawa term in the extended local hidden gauge approach, we search for states dynamically generated from the interaction, and find two states with small width, which we associate to the Λb( ) and Λb( ) states. in addition to these two Λb states, we find three more states with i = and eight more states in i = , some of which are degenerate in different spin j. keywords: coupled channels, box diagram, heavy quark spin symmetry . introduction recently, the discovery of the two Λb excited states by the lhcb collaboration [ ], Λb( ) and Λb( ) with j p = / −, / − respectively, drives more attention to the beauty sector, since the widths of these two states are very small, less than mev. the higher one is also confirmed by the cdf collaboration [ , ]. in the present work, following the works [ , , , ], we investigate the open beauty system of meson-baryon interaction, using the extended local hidden gauge for- malism and the coupled channel approach. the assump- tion that the heavy quarks act as spectators at the quark level automatically leads us to the results of the heavy quark spin symmetry for pion exchange. . formalism we investigate the coupled channels πΣb, πΛb, ηΛb, ηΣb, b̄n with i = , . similarly, we also study the b̄∗n and πΣ∗b, ηΣ ∗ b, b̄Δ, b̄ ∗Δ channels, belonging to a decuplet of / + states. using the local hidden gauge ∗presenter p p b b(a) v(q) v v b b(b) v(q) figure : diagrammatic representation of the pseudoscalar-baryon in- teraction (a) and vector-baryon interaction (b). approach, the meson- baryon interaction proceeds via the exchange of vector mesons as depicted in fig. . assuming that the heavy quarks act as spectators in the dominant terms of the interaction, with the extended local hidden gauge approach from the exchange of light vector mesons, the transition potential is given by vi j = −ci j f ( √ s − mbi − mb j ) × √ mbi + ei mbi √ mb j + e j mb j , ( ) with f the pion decay constant (for light vector mesons exchange, taking f = fπ = mev), √ s the energy in the center mass frame, mbi, ei (mb j, e j) the mass, energy of baryon of i ( j) channel. the ci j coefficients available online at www.sciencedirect.com nuclear and particle physics proceedings – ( ) – - /© published by elsevier b.v. www.elsevier.com/locate/nppp http://dx.doi.org/ . /j.nuclphysbps. . . http://www.elsevier.com/locate/nppp http://dx.doi.org/ . /j.nuclphysbps. . . http://dx.doi.org/ . /j.nuclphysbps. . . http://www.sciencedirect.com are given in refs. [ , ] for the pseudoscalar meson- baryon interactions and in refs. [ , ] for the vector meson-baryon interactions. in coupled channels we use the bethe-salpeter equa- tion to evaluate the scattering amplitudes t = [ − v g]− v, ( ) where g is the diagonal matrix of the loop function for the propagating intermediate meson baryon channels, and the elements of the kernel v are given by eq. ( ). first, using the coupled channels approach, we inves- tigate the sector of b̄n and its coupled channels, and the sector of b̄∗n and its coupled channels, respectively. but, it is difficult to dynamically reproduce the two Λb excited states with a reasonable cutoff. more details can be seen in our recent paper [ ]. next, we break the degeneracy of the / −, / − states of the b̄∗n sector, by mixing states of b̄∗n and b̄n in both sectors. this means that it is sufficient to evaluate the contribution of the box diagrams as below: n n n b̄∗ b̄ b̄∗ π π finally we obtain the following results for the b̄∗n → b̄n → b̄∗n box diagram j = / : δv = f ac ( ∂ ∂m π i′ + i ′ + i ′ ) , j = / : δv = f ac ( ∂ ∂m π i′ ) , ( ) where i′ = ∫ d q ( π) �q ωb(�q ) mn en (�q ) num den , i′ = ∫ d q ( π) �q ωb(�q ) mn en (�q ) num den , ( ) i′ = ∫ d q ( π) ωb(�q ) mn en (�q ) × p in + k in − en (�q ) −ωb(�q ) + i� , with f ac = g (mb∗ mk∗ ) (f + d fπ ) , num = k in − en (�q ) − ωπ(�q ) −ωb(�q ) + p in, den = ωπ(�q )[p in −ωπ(�q ) −ωb(�q ) + i�] ×[k in − en (�q ) −ωπ(�q ) + i�] ×[p in + k in − en (�q ) −ωb(�q ) + i�], and p in, k in the energies of incoming b̄ ∗ and n, g = mv/ fπ with mv ≈ mev, d = . and f = . [ ]. for the other boxes, such as b̄n → b̄∗n → b̄n for i = , and for i = b̄Δ → b̄∗Δ → b̄Δ, b̄∗Δ → b̄Δ → b̄∗Δ, b̄Δ→ b̄∗n → b̄Δ, b̄∗Δ→ b̄n → b̄∗Δ, we obtain similar results and more details can be referred to our paper [ ]. . results when we consider the mixing of b̄∗n and b̄n states by taking into account the contribution of the box dia- gram for the channels of b̄∗n and b̄n with their coupled channels, we obtain the energy splitting of mev be- tween the j = / and j = / in the sector of b̄∗n and its coupled channels, which is rather independent of the cutoff used. thus, by tuning the cutoff qmax to get the right binding, we find qmax = mev leading natu- rally to two Λb states, where the energy of the j = / state is mev, and the one of the j = / state mev, associating them to the Λb( ) and Λb( ). then, with this fixed cutoff, we search the generated states in other isospin i = and i = sectors. finally, since we have many intermediate results, we summarize all the results that we obtain with qmax = mev. the results are shown in table , where we also write for a quick intuition the main component of the states. table : energies and widths of the states obtained and the channels to which the states couple most strongly. channels j i (e, Γ) [mev] exp. b̄n . , - πΣb . , . - b̄∗n . , Λb( ) b̄∗n . , Λb( ) ρΣb . , . - ρΣb . , . - b̄n, πΣb . , . - πΣb . , . - b̄Δ, πΣ∗b . , - πΣ∗b . , . - b̄∗n , . , - ρΣb , . , . - b̄∗Δ , , . , - ρΣ∗b , , . , . - c.w. xiao et al. / nuclear and particle physics proceedings – ( ) – in the work of ref. [ ], the same interaction as here is used for the main diagonal channels, but the transi- tion between different coupled channels is not obtained through vector or pion exchange as done here, but in- voking a combined su( ) and heavy quark spin sym- metry. comparing the results with ref. [ ], we obtained some consistent results in i = . the two states asso- ciated to the Λb( ) and Λb( ) exhibit, as here, a substantial coupling to b̄∗n. there is also a / − state in that work at mev which we find at mev, only mev higher, and another state at mev that we find at mev, mev below. the mostly ρΣb state found here at mev, basically degenerate in j = / , / , was either not found or not searched for in that work because of its higher mass. the states of i = are not investigated in that work. thus, these states are our predictions with the same pa- rameters in i = , and we find quite a few, some of them narrow enough for a clear experimental observation. in summary, we predict states with i = , two of them corresponding to the Λb( ) and Λb( ), and states with i = . the energies of the states range from about mev to mev. . conclusion the interaction of b̄n, b̄Δ, b̄∗n and b̄∗Δ states with its coupled channels are investigated in the present work by using dynamics mapped from the light quark sec- tor to the heavy one. we studied the interaction of the b̄n, b̄Δ, b̄∗n and b̄∗Δ with their coupled channels πΣb, πΛb, ηΣb (for the b̄n); πΣ∗b, ηΣ ∗ b (for the b̄Δ); ρΣb, ωΛb, φΛb, ρΣ∗b, ωΣ ∗ b, φΣ ∗ b (for the b̄ ∗n); and ρΣ∗b, ωΣ ∗ b, φΣ∗b (for the b̄ ∗Δ), and looked for poles of the scatter- ing matrix in different states of spin and isospin. we found six states in i = , with one of them degen- erate in spin j = / , / and two of them associ- ated to the experimental Λb( ) and Λb( ) states, which couple mostly to b̄∗n. we also obtained eight states in i = , less bound, two of them degenerate in spin j = / , / , and two more degenerate in spin j = / , / , / . we look forward to future exper- iment searches of the baryon states with open beauty predicted here. references [ ] raaij et al. [lhcb collaboration], phys. rev. lett. , ( ) [arxiv: . [hep-ex]]. [ ] t. a. aaltonen et al. [cdf collaboration], phys. rev. d , ( ) [arxiv: . [hep-ex]]. [ ] p. palni [ for the cdf collaboration], arxiv: . [hep-ex]. [ ] j. -j. wu, l. zhao, b. s. zou, phys. lett. b , ( ) [arxiv: . [hep-ph]]. [ ] c. garcia-recio, j. nieves, o. romanets, l. l. salcedo and l. tolos, phys. rev. d , ( ) [arxiv: . [hep-ph]]. [ ] c. w. xiao and e. oset, eur. phys. j. a , ( ) [arxiv: . [hep-ph]]. [ ] p. g. ortega, d. r. entem and f. fernandez, phys. lett. b , ( ) [arxiv: . [hep-ph]]. [ ] e. oset and a. ramos, nucl. phys. a , ( ) [nucl- th/ ]. [ ] s. sarkar, e. oset and m. j. vicente vacas, nucl. phys. a , ( ) [erratum-ibid. a , ( )] [nucl-th/ ]. [ ] e. oset and a. ramos, eur. phys. j. a , ( ) [arxiv: . [hep-ph]]. [ ] s. sarkar, b. -x. sun, e. oset and m. j. vicente vacas, eur. phys. j. a , ( ) [arxiv: . [hep-ph]]. [ ] w. h. liang, c. w. xiao and e. oset, phys. rev. d , ( ) [arxiv: . [hep-ph]]. [ ] b. borasoy, phys. rev. d , ( ) [hep-ph/ ]. c.w. xiao et al. / nuclear and particle physics proceedings – ( ) – working paper / age before beauty? productivity and work vs. seniority and early retirement giovanni mastrobuoni filippo taddei age before beauty? productivity and work vs. seniority and early retirement ∗ giovanni mastrobuoni† filippo taddei‡ may abstract we show how the age profile of earnings, retirement rules and retirement behavior are tightly linked through the general equilibrium of the economy. generous social security benefits financed by large social security taxes discourage human capital accumulation. in social security systems where social security benefits prioritize redistribution less productive workers with lower levels of human capital tend to retire earlier. these outflows of workers from the labor force tend to generate wage profiles that are monotonically increasing over age and labor markets that display larger seniority premia. this paper theoretically rationalizes the links between retirement rules and the wage structures over the life cycle and uses data on european countries to show how social security taxes, the age profile of earnings, and retirement behavior are related. keywords: social security tax, early retirement, age profile of earnings, human capital, seniority premium jel classification codes: h ; h ; d ∗we thank elsa fornero and flavia coda moscarola for their help, and participants at the alpop conference for their comments. we are grateful to regione piemonte and netspar for their financial support. †collegio carlo alberto, cerp and netspar, , via real collegio , moncalieri (to), italy, e-mail: gio- vanni.mastrobuoni@carloalberto.org. ‡collegio carlo alberto and cerp, via real collegio , moncalieri (to), italy. e-mail: fil- ippo.taddei@carloalberto.org introduction social security systems are likely to come under severe financial stress in the near future, mainly because of the progressive aging of populations. by , the ratio between the elderly population (aged and above) and the working age population (aged to ) is expected to double with respect to its level in almost all european countries (visco, ). the ratio between retirees and people of working age is going to increase even more dramatically (galasso, ). developed economies, starting with china, will soon face similar generational tensions. even though the financial distress of social security systems (ssss) in advanced economies resembles a ticking bomb, the pace of reforms does not appear to be sufficiently fast. the explanation for this delay is probably linked to the shift in the demographic structure toward old age: it is politically easier to shift the burden of the reforms to the younger generations. we argue that the reforms need to be accelerated to avoid additional increases in social security taxes. as we show in this paper, these increases are likely to have major effects by leading to changes in the level of human capital and in the age profile of wages. we not only rationalize these features in the general equilibrium of the economy, but also show they are related to each other within european countries. academics and policy-makers often overlook that social security rules are interlinked with the age profile of productivity and earnings over workers’ careers. we show in this paper that these two characteristics of the economy are part of the same general equilibrium. in fact, the age at which an agent chooses to retire depends on his stock of human capital in so far human capital determines their productivity in the labor market. the reason is simple: the higher is human capital, the higher is labor income, and so the smaller is the incentive to retire. since, in general, people differ in their ability to acquire and maintain human capital, less productive individuals retire in disproportionate number from the labor force. but this observation is not enough to rationalize the starkly different behavior in retirement decision across workers in different european economies. the crucial observation we make here gives a central role to the level of social security taxation. in the empirical evidence we present regarding european countries, we highlight that the average retirement age tend to be lower in countries where social security taxes are higher and the labor market, including the private sector, rewards relatively more seniority. we propose a general equilibrium perspective to systematically rationalize these features. the intuition is the following. in economies where the social security tax is high, the private benefit of human capital accumulation are reduced while the social security benefits tend to be large and the early retirement age tends to be low. then only the most productive individuals find it convenient to remain workers because their high human capital commands high wages. the selection among workers is reflected in the average wage observed among more senior workers and in the aggregate the labor market displays a more pronounced seniority premium. as a consequence of high social security taxation and the resulting low investment in human capital, the aggregate effective human capital is reduced, labor income stays stagnant and, on average, individuals retire earlier. while the age profile of wages is increasing for economies with high social security tax, this is not the case, by a specular reasoning, when social security taxes are low. in these economies even low productivity individuals find it convenient to accumulate more human capital and remain active in the labor market for longer periods. in this latter group of economies the average wage by age class follows the dynamic of individual human capital: it first increases and then it decreases in the second half of the working career. the age profile of wages takes a more hump-shaped structure and the seniority premium falls. this study has two main contributions, both a theoretical and an empirical one, relating social security rules and the age profile of wages. first, while we are certainly not the first to observe that social security in general and the level of social security taxation in particular affects the accumulation of human capital and retirement decision, especially among the least productive individuals, (conde-ruiz et al., , conde-ruiz and galasso, , ), this is to our knowledge the first paper to link it the shape of the age profile of earnings to ssss and to highlight how these profiles differ among european countries in terms of the seniority premium. differently from the seminal contribution of lazear ( ), we show how these differences do not necessarily reflect discrepancies between the wage and individual productivity. establishing this link is not just an intellectual curiosity, but it is an important observation for policy. as ssss enter additional distress because of the aging population, policy reforms point in the direction of increasing the level of social security taxation, possibly in alternative to an retirement age increase. as we point out in this paper, policymakers should be particularly wary of taking this view because raising social security taxation not only decreases human capital, but it also has the effect of making individuals, especially but not only the low productivity ones, less eager to remain in the labor force. we also provide an empirically valid measure of the severity of this phenomenon: the seniority premium observed in the labor market. the first part of the paper develops a general equilibrium model to help to systematically tie together the age profile of earnings and social security. the second part provides cross- country evidence supporting the view that there is a robust empirical relationship, within european countries, between high social security taxes, low investment in human capital, labor markets that reward more seniority, early retirement and low labor market participation at old age. the economy consider an economy inhabited by overlapping generations of individuals living for t periods, all with size one. we use jt to denote the set of individuals born at time t, i.e. generation t. time starts at t = and then goes on forever. individuals jt leave the economy at the end of period t + t. each individual acquires human capital that depreciates over time in order to foster his produc- tivity and income. we label the amount of human capital by individual j of generation t at time i by hit(j), i ∈ {t, ..., t + t}. wherever ambiguous, we will adopt the notational convention that, respectively, the subscript t identifies the generation and the superscript i identifies the period to which the variable refers. human capital is valuable because it increases individual’s productivity, and thus the effective wage while working. every individual j ∈ jt maximizes the sum of her lifetime income, net of the cost of human capital accumulation: ut(j) = t+t∑ i=t y(hit(j)) −c j(hit(j)), ( ) where cj(ht(j)) = t+t∑ i=t cj(xit(j)), hit(j) =   xit(j) if i = t hi− t (j)( − δ) + xit(j) if i > t , ( ) dcj(xit(j)) dxit(j) > , d cj(xit(j)) d xit(j) < . y(.) is per period income, cj(.) is the total cost of the sequence of human capital accumulated over individual j’s life, i.e. ht(j) = [h i t(j)]i∈{t,...,t+t}. the strictly convex function c j(.) is a reduced form expression that captures the individual specific cost of education, the opportunity cost of learning on the job and, in general, all the resources required to build up and maintain the vector of human capital ht(j) by individual j. it should be noted that, in our setup, the cost to maintain the level of human capital hit(j) of individual j in period i depends only on the amount added by the individual in that specific period, i.e. xit(j). the crucial feature of this economy is that individuals differ in their ability to acquire skills and human capital and this difference is persistent over the life cycle. formally, this heterogeneity is captured by the function cj(.) that we assume to be increasing in the label j, for any given level of human capital hit. this means that if we compare individual j > j, then the marginal cost of human capital is higher for j: dcj(x) dx > dcj(x) dx , ∀x. ( ) the second crucial feature of our setup is that agents do not only invest in human capital that is useful to work, but they also decide when they exit the labor force and retire, conditional on the institutional constraints that may exist. once an individual stops working, she retires to collect from the sss a (possibly time variant) benefit. formally, r j t is the label we apply on the period in which individual j of generation t exits the labor force and retires. therefore an individual j with the level of human capital hit(j) in period i obtains an income at time t̃ equal to: yt̃(hit(j)) =   wt̃(h i t(j)) = wt̃( − τ) ·f [h i t] if j works, i.e. t̃ ∈ { t, ...,r j t − } bt̃(j) if j is retired, i.e. t̃ ∈ { r j t , ..., t + t } where f [.] is an increasing, strictly concave and differentiable function that translates individual human capital into actual efficiency units useful for production, wt̃ is the time dependent unitary wage for each efficiency unit, τ is the social security tax and bt̃(j) is the social security benefit an individual receives after she leaves the labor force. the concavity of f [.] is meant to capture the realistic feature that, although productivity is increasing in the level of individual human capital, it is so at a decreasing rate. for the sake of simplicity we will abstract from social security debt and we will assume through- out the analysis that the sss accounts are always balanced. therefore, we have: wtτ · ∑ r j k − ≥t (∫ jk f [ htk(j) ] dj ) = ∑ r j k ji would also choose to retire in period i because it is also more costly for him to accumulate human capital than for individual ji. therefore we can also define, for a generic individual j, the beginning of retirement by the first period rj satisfying the minimum age requirement and condition ( ): rj = min i ∈{ , ...,t} rj≥κ, κ∈{ ,...,t} : w ( hi(j) ) · ( − τ) − cj(xi(j)) ≤ b(j) = b ( ) for a given social security tax τ and sequence of social security benefit b, maximization of utility ( ) with respect to the human capital xit(j) that individual j of generation t accumulates in period i satisfies the following: max ht(j)=[hit(j)]i∈{t,...,t+t } u(j) ⇔ a · ( − τ) · ∑rjt− z=i ( − δ) (z−i) ∂f[hz(j)] ∂xz(j) = ∂[cj(xit(j))] ∂xit(j) ( ) the condition ( ) has an intuitive interpretation. first, it states that the benefit of investing in the build-up of human capital depends on the future wages this investment secures, ∑rjt− z=i ( − δ)(z−i) ∂f[hz(j)] ∂xz(j) , net of taxation (τ). second, in every period, agents build up additional human capital until its marginal cost, ∂[cj(xit(j))] ∂xit(j) , equates its marginal benefit. by joining ( ) and the assumption that agents have heterogenous ability to accumulate human capital - condition ( ) - it is immediate to observe that the level of human capital investment falls with the individual’s ability to accumulate it, i.e. cj(.). formally: xi(j′) < xi(j) if j′ > j ( ) most interestingly from our point of view, we can now study how the level of human capital changes over the life cycle of a generic individual. given the level of the social security tax τ, condition ( ) shows that the largest investment in human capital takes place at the beginning of life. the reason is straightforward: the marginal benefit - ∑rjt− z=i ( − δ) (z−i) ∂f[hz(j)] ∂xz(j) - is the highest and the marginal cost - ∂[cj(xit(j))] ∂xit(j) - is the same. as individuals age the marginal cost remains the same, while the marginal benefit falls progressively as the same human capital investment now commands lower future wages because of the reduced working horizon and the concavity of human capital effectiveness - f [.]. therefore, the investment per period in human capital decreases as individuals approach retirement age, i.e. i → rj. but since, as setup in condition ( ), human capital depreciates over time at the constant rate δ, it is straightforward to conclude that the stock of human capital, hi(j), must initially increase over the first part of the working career, peak around its middle and fall as retirement becomes closer and closer. eventually the effect of depreciation dominates the effect of additional investment in human capital and so the stock of human capital hit(j) falls as retirement approaches, i.e. i → r j t . therefore, while at the beginning of the working career the additional investment in human capital is large and more than enough to compensate for the fall in the stock of human capital due to depreciation, this ceases to be the case as the stock of human capital increases and the marginal benefit of human capital investment falls. moreover, it is important to notice that the just described behavior of human capital over the life cycle must take place, irrespective of the individual ability to accumulate human capital, i.e. cj(.). it is due solely to the fact that, while the benefit of human capital is time varying, the cost of human capital built up is not. now we can join our observations about the optimal retirement decision with those regarding the life cycle of human capital. by condition ( ), we know that the age at which agent chooses to retire depends on her stock of human capital and so, eventually, on her ability to acquire human capital, i.e. on cj(.). the reason is simple: the higher the human capital, the higher the labor income, the smaller the incentive to retire and the later people retire from the labor force. but in principles it would be easy to speculate that also the cost of building up human capital is time varying and is, in particular, increasing as individuals age. if this feature were to be introduced here, it would strengthen our arguments. this is not enough to explain why we observe starkly different behavior regarding retirement in different economies. the crucial observation we make here gives a central role to the level of social security taxation τ. in the empirical sections that follow we show that countries where the social security tax is high are also the ones where retirement takes place earlier and where the labor market, including the private sector, rewards relatively more seniority. we now try to rationalize these features through the framework we have proposed here. if the sss picks a high level of the social security tax, condition ( ) shows that the marginal benefit of human capital accumulation falls. these has two effects: first, it decreases the overall level of human capital for any individual and at any age, i.e. ∀j,i; second, it increases the level of the social security benefit b relatively to the wage, as condition ( ) dictates, and so it builds an incentive for workers to retire earlier. but which individuals remain longer in the workforce? once again, these are the most productive so that we would also observe that, as social security taxation increases, the marginal worker ji that is indifferent between working and retiring - defined by condition ( ) - falls, labor market participation also falls but the average wage of active individuals increases. the increase is the average wage is not the result of a surge in productivity of senior workers, but rather the effect of selection pushed forward by the incidence of the social security tax. in economies where the social security tax τ is higher, the private benefit of human capital accumulation falls, the social security benefit provided by sss instead increases, but then only the most productive individuals find convenient to remain workers and postpone retirement. this selection is reflected in the average wage observed among senior workers and the labor market thus displays a more pronounced seniority premium that is though the consequence of the structure of the sss, and not of a crucial function that senior workers provide in the economy. as a consequence of high social security taxation and the resulting low investment in human capital, the aggregate effective human capital h is reduced, labor income stays stagnant and individuals face on average a strong incentive to retire earlier, whenever the sss rules allows so. the selection taking place among workers as a consequence of the high level of the social security tax that some ssss display is responsible for the fact that the average wage by age class among active workers increases with seniority. while the age profile of earnings is increasing for economies with high social security tax, a specular reasoning help us to conclude that ssss with low social security tax do not present such a thorough selection among workers. thus the average wage by age class first increases and then decreases in the second half of the working career. the age profile of earnings takes a more hump-shaped structure in these economies and the seniority premium falls. the following proposition summarizes our discussion: proposition . . under the sss defined above, we have: . the stock of human capital hi(j) first increases and then decreases over the life cycle, ∀j; . the aggregate level of human capital h decreases as social security tax, τ, increases; . the retirement age rjdecreases as social security tax, τ, increases, ∀j; . the ratio between average working income at the time of retirement and at entry in the labor market, i.e. the seniority premium, ∫ w(hr j (j))dj∫ w(hi= (j))dj , increases as social security tax, τ, increases. empirical evidence . differences in the age profile of earnings across european coun- tries policy makers might not realize that social security rules influence labor market features, so that the age profile of earnings accommodates to specific social security rules. given that social security rules hardly vary within a country we are going to analyze differences across countries, and we do so using the european community household panel (echp), a representative panel of the european workers. figure shows the pattern of wage profiles in european countries. each line represents a different cohort, defined as individuals born in the same decade. these lines represent the average log wage across age, and are based on simple wage regressions shows in table . in italy, for example, wages of older workers grow over time as much as those of younger workers. in the united kingdom this is not the case: wages for the cohort drop over time! in general, countries seem to differ quite extensively by how concave the age profile of earnings is. southern countries like spain and greece, and, as we just showed, italy, show no evidence of bending of wages across age. these are typical countries where strong seniority systems seem to be in place. the wage-age profile is clearly different in the united kingdom, germany, the netherlands, and denmark, where not only wages at older ages decline across generations, even within cohorts the slope tends to get flatter. roughly speaking, european countries can, on the basis of their seniority premium, be divided into two groups. in the first group we find austria, belgium, italy, and spain where labor markets are relatively more rigid, less favorable to entry, and workers are more protected when employed. such conditions lead to higher youth unemployment (echp - ), which creates downward pressure on wages of younger workers. this pressure diminishes as workers age, and with age we observe falling unemployment rates. moreover, hourly wages in the private sector increase with seniority ( labor force survey, eurostat and echp, - ) even when workers’ productivity is unlikely to do so. even though measuring productivity at the worker level is hard, no available evidence suggests that average productivity increases with age (see roger and wasmer ), certainly not after a certain age (see skirbekk and abowd and kramartz, ), while the theoretical literature argues that productivity is hump-shaped during a worker’s career ((ben-porath, ), (kredler, )). we are going to assume that, conditional on observable characteristics (including educa- tion, occupation, industry, and the like), there are no ex-ante systematic differences in the age profile of productivity of individual workers across developed european countries, other than be- cause of differences in human capital investments. but productivity might still differ ex-post if more productive workers are less likely to retire that less productive ones. if a country presents higher premia for seniority, there is a selection that would leaves only the most productive individuals active in the labor market at late ages. as first noticed by lazear ( ) in a different context, if wages do not adjust efficiently to the shifting composition of the labor force, this creates an incentive for employers to push for social security rules that mandate early retirement. in the second group of countries we find economies with more flexible labor markets like the uk, germany and sweden, wages appear to track individual productivity more closely. in these countries, salaries increase at the beginning of a workers’ career, up to age - , to fall later on as workers approach retirement. unlike the previous case, in these economies unemployment rates for younger and older workers are similar, even across skill groups. thus, with these labor markets firms have no particular incentive to prefer young workers to older ones. workers tend to work longer, because wages and individual productivity are more aligned and social security benefits also tend to be less generous. . the relationship between the age profile of earnings and retire- ment rules this section is going to shed some light on the relationship between the seniority system and several measures of social security generosity. let us first define the specific feature of the labor market on which we will focus. based on the wage-age profiles seen before we can rank countries based on the difference in the slope of wages between the cohort and the one. the higher that difference the more flexible the labor market. table shows that different slopes, that we derived in regressions outlined in the appendix. table instead, shows the difference in slopes. the negative of it is simply what we call the seniority premium. the closer to zero is the difference, the more similar are the changes in the hourly wage because of every additional year spent in the labor market between young and older workers, and thus the higher is the seniority premium. the first evidence we provide is about what happens early in life, and how these decisions influence the age profile of earnings. the left panel of figure shows that in countries that have higher social security taxes workers invest much less in human capital, and the relationship seems strong and approximately linear. how this lower investment influences the earnings profiles is shown in the second panel. countries where workers accumulate higher levels of human capital tend to have concave wage profiles, meaning that in these countries wages do not steadily increase with age. in other words, where workers invest less in human capital these same workers seem to withdraw earlier from the labor market. the next step is to define the generosity of the social security system. we’ll proxy for the generosity using several different measures. table shows the first set of these measures, the ones based on the retirement age. the idea is simple, the lower the retirement age, the more generous the system. the upper-left panel in figure shows the correlation between the early retirement age as set by law and the seniority system. the correlation is negative but far from perfect. most probably a better measure for the overall generosity is the average retirement age, as it also depends not only on the constraints set on ages but also on the overall generosity and on actuarial adjustments to the benefits when retirement is postponed. the second panel does indeed show a stronger correlation. as before, the higher the labor market flexibilities, the higher the retirement age. using the median shows similar results and what works even better is the lowest quartile of retirement age, probably because it highlights that some countries (italy more than others) allow very early exits from the labor market and have very strong seniority systems. the regression line shown in these figures are all weighted by the population of countries. another way to measure generosity is by looking at replacement rates. table shows the different replacement rates. we computed them exploiting the panel as the benefits divided by the last wage. figure shows the corresponding correlations with the seniority premium. the larger the replacement rate the higher the seniority premia. the negative correlation between retirement age and the seniority premium is a striking fact that turns out to be empirically robust to a series of control (educational classes, gender, and other demographics). conclusions and future developments we highlighted the relationship in equilibrium between social security rules and the age profile of earnings. we showed that this relationship holds for european countries and developed a simple theoretical rationalization of this result. social security rules and the implied social security tax provide strong incentives for the level and the pattern of accumulation of human capital over the life-cycle. the main policy implication of this perspective is that social security reforms are closely linked to labor market reforms. this is, in our opinion, the main reason why countries have had such a hard time to reform their sss: they often neglect the deep relationship between the labor market, specifically investments in human capital and the age profile of earnings, and retirement rules. let us complement the intuition set forth here with some additional features that are certainly relevant and that we intend to develop in the future. to fix ideas, think about economies with european-type labor markets: contracts are long term because employment protection legislation prevents employers from firing workers at will. the cross-country evidence we have produced shows that in countries where, on average, retirement takes place later, the difference between how much wages change in the first and the second half of workers’ career is larger. this is the main prediction of the macroeconomic general equilibrium model we set up. in labor markets where the seniority premium is relatively large, both employers, and older and low skilled workers end up preferring a “loose” sss: they pay higher social security taxes to support looser retirement requirements. this allocation is an equilibrium allocation that is only apparently paradoxical. in fact, when the age profile of earnings displays a large seniority premium, firms are happy to see older workers enter retirement. the reason is that, although the wage of these workers is likely to be higher, their productivity is unlikely to be so. therefore employers would like instead to hire more productive younger workers who are likely to be paid below their productivity. moreover, low skilled workers are also eager to exploit the looser retirement requirements and leave the labor force early, maybe taking advantage of the opportunities offered by the informal economy. the coalition between old and low skilled workers and employers makes a generous sss politically sustainable, against the interest of the young generations that suffer high unemployment and, most importantly, contrary to the general interest of the economy. in labor markets displaying low seniority premium instead, wages and productivity tend to be more aligned across different age groups, and for older workers in particular. employers have low incentives to lobby for early retirement provisions and they shift their support towards stricter retirement requirements in exchange for lower social security contributions. notice the innovation of the mechanism we just described compared with conde-ruiz and galasso ( , ). in their papers, it is the fact that the median voter becomes relatively older to shift the equilibrium of the sss. in our model it is the interaction between the age profile of earnings and social security rules, even if the median voter age does not change, to determine the equilibrium sss of the economy. while both models coincide in predicting the support of low skilled workers for loose requirements for early retirement, in addition to them we could argue that employers too may favor “loose” ssss when the age profile of earnings rewards relatively more seniority. unsurprisingly, a richer version of our argument also predicts that rigid labor markets severely reduce labor force participation for workers aged - or - (gruber and wise ( , )), an implication that finds strong empirical support. interestingly enough, there are important cross-country variations in the way these “loose” systems are designed, with disability/sickness and unemployment benefits playing a more prominent role in some countries, and old-age benefits playing a more prominent role in others. the rationalization provided by our model is not just a theoretical curiosity but it suggests how much society would gain by changing the retirement rules depends on the underlying age profile of earnings, i.e. on the labor market structure. moreover, the shape of the age profile of earnings is a crucial determinant of how losses and gains due to the sss are distributed across skill groups and generations. after providing a rational for the observed cross-country relationship between ssss and age profiles of earnings, we plan to extend our insights to study the puzzling high unemployment rate among high skilled young workers in italy, greece and spain, the three countries displaying the largest seniority premium (see figure ). this is particularly interesting since economies without a seniority effect do not display this feature. but our extended perspective could rationalize this difference: if a generous sss is associated with wage profiles that rewards relatively more seniority, less skilled elderly workers take advantage of the more flexible sss requirements and retire. the more skilled elderly workers instead stay on the job longer: this asymmetry generates a relative abundance of skilled elder workers in the labor market. this relative abundance in turn delays the entry of young high skilled workers and is thus likely to be an important cause of the observed high unemployment rates in this skill group. this observation is not only important for its redistributive implications but also for its dis- couraging effect on human capital accumulation in early periods of the life-cycle. this is one of the causes – one could argue – for staggering productivity growth and the relatively lower number of university graduates displayed in the set of countries with more generous retirement rules. in conclusion, this framework may also be fruitfully employed to analyze how low entry wages and low levels of education feed back into workers’ fertility decisions. low entry wages are likely to lower fertility and thus exacerbate the financial burden of the sss. an age profile of earnings providing higher seniority premium, with the feature of low entry wages, also keeps young people financially dependent on their parents, thus reinforcing the status quo in these economies even further. references john m. abowd and francis kramarz. the analysis of labor markets using matched employer-employee data. in handbook of labor economics, volume , pages – . . url http://www.sciencedirect.com/science/article/b p v- fj vr -y/ / bda b a e fe f e . yoram ben-porath. the production of human capital and the life cycle of earnings. the jour- nal of political economy, ( ): – , august . url http://www.jstor.org/stable/ . ignacio j. conde-ruiz, vincenzo galasso, and paola profeta. the evolution of retirement. cepr discussion papers , c.e.p.r. discussion papers, january . url http://ideas.repec. org/p/cpr/ceprdp/ .html. ignazio j. conde-ruiz and vincenzo galasso. early retirement. review of economic dynamics, ( ): – , january . url http://ideas.repec.org/a/red/issued/v y i p - . html. ignazio j. conde-ruiz and vincenzo galasso. the macroeconomics of early retirement. journal of public economics, ( - ): – , august . url http://ideas.repec.org/a/eee/ pubeco/v y i - p - .html. vincenzo galasso. the political future of social security in aging societies. mit press books, edition , volume , september . isbn x. johnathan gruber and david a. wise. social security and retirement around the world. uni- versity of chicago press for nber, chicago, february . isbn . johnathan gruber and david a. wise. social security and retirement around the world - micro- estimation. university of chicago press for nber, chicago, march . isbn . http://www.sciencedirect.com/science/article/b p v- fj vr -y/ / bda b a e fe f e http://www.sciencedirect.com/science/article/b p v- fj vr -y/ / bda b a e fe f e http://www.jstor.org/stable/ http://www.jstor.org/stable/ http://ideas.repec.org/p/cpr/ceprdp/ .html http://ideas.repec.org/p/cpr/ceprdp/ .html http://ideas.repec.org/a/red/issued/v y i p - .html http://ideas.repec.org/a/red/issued/v y i p - .html http://ideas.repec.org/a/eee/pubeco/v y i - p - .html http://ideas.repec.org/a/eee/pubeco/v y i - p - .html matthias kredler. experience vs obsolescence: a vintage-human-capital model. universidad car- los iii madrid, mimeo, . url http://papers.ssrn.com/sol /papers.cfm?abstract_ id= . edward p. lazear. why is there mandatory retirement? journal of political economy, ( ): – , december . url http://www.jstor.org/sici?sici= - ( ) : % c :ipalc% e . .co; -x&origin=repec. ocse. pensions at a glance : retirement-income systems in oecd and g countries. oecd publishing, . url http://dx.doi.org/ . /pension_glance- -en. muriel roger and malgorzata wasmer. labour productivity differentiated by age and skills. working paper, august . url http://www.eale.nl/conference /papersc/wasmer. pdf. vegard skirbekk. age and individual productivity: a literature survey. in g. feichtinger (ed.), vienna yearbook of population research, austrian academy of sciences press, . isbn - - - . ssa. social security programs throughout the world: europe, . social security administra- tion; research, statistics, & policy analysis, . url http://www.ssa.gov/policy/docs/ progdesc/ssptw/. ignazio visco. ageing and pension system reform: implications for financial markets and economic policies. report, report for the deputies of the group of ten, september . url http: //www.imf.org/external/np/g / /pdf/ .pdf. http://papers.ssrn.com/sol /papers.cfm?abstract_id= http://papers.ssrn.com/sol /papers.cfm?abstract_id= http://www.jstor.org/sici?sici= - ( ) : % c :ipalc% e . .co; -x&origin=repec http://www.jstor.org/sici?sici= - ( ) : % c :ipalc% e . .co; -x&origin=repec http://dx.doi.org/ . /pension_glance- -en http://www.eale.nl/conference /papersc/wasmer.pdf http://www.eale.nl/conference /papersc/wasmer.pdf http://www.ssa.gov/policy/docs/progdesc/ssptw/ http://www.ssa.gov/policy/docs/progdesc/ssptw/ http://www.imf.org/external/np/g / /pdf/ .pdf http://www.imf.org/external/np/g / /pdf/ .pdf figure : profile of the log hourly wage by country and cohort notes: cohort classes group individuals born in the same decade (i.e. cohort groups individuals born in the decade - ) figure : seniority premium, social security taxes, and human capital notes: human capital is measured using the isced classifications. the social security taxes are taken from ocse ( ) and ssa ( ). figure : seniority premia against various measures of early retirement provisions notes: the uk and the netherlands have no early retirement (here we are not accounting for disability retirement), old age requirements are reported in the place of early retirement requirements. figure : seniority premium against median rr - panel approach notes: based on echp data. table : slopes of log hourly wage profile (euro reported in prices), by country and cohort - men isp basic denmark . . . . . . the netherlands . . . . . . belgium . . . . . . france . . . . . . ireland . . . . . . italy . . . . . . greece . . . . . . spain . . . . . . portugal - . . . . . . austria - . . . . . . finland - . . . . . . germany . . . . . . luxembourg . . . . . . uk - . . . . . . notes: data echp for the period - . for germany, luxembourg and the uk we use the echp surveys, the soep, psell and bhps. the surveys of austria and luxembourg start from , the one of finland starts from . sweden is omitted as there are no data on monthly net wages. slopes are derived from an ols regression of the log hourly wages on the age and a constant. the basic inverse seniority premium (isp basic) is the difference between the slope of the log hourly wage profile for the cohort and the one for the cohort . table : inverse seniority premium - men country basic specification enriched specification denmark . . the netherlands . . belgium . . france . . ireland . . italy . . greece . . spain . . portugal . . austria . . finland . . germany soep . . luxembourg psel . . united-kingdom bhps . . notes: in the basic specification the inverse seniority premium is obtained as the difference between the coefficient of the variable “age” in the ols regression of the log hourly wage on the age (and a constant) for the cohort and the one in the regression for the cohort (see table ). in the enhanced specification the inverse seniority premium is the coefficient of the interaction term of the variable “age” and the dummy for “cohort ” in the ols regression of the log hourly wage on the age and some other regressors, where the “cohort ” is the baseline (see table bis). regression controls for age, good health, disability, education, being someone that retires in the observed period (retiring), cohort and interaction between “age” and “retiring”, interactions between “age” and “cohort”. there is no info on disability in first wave (disab== for all) and no health information for luxembourg. table : retirement age by country by lawa from sample datab old early mean median percentile country age retirement ret. age ret. age ret. age denmark the netherlands · · · belgium france ireland italy greece spain portugal austria finland germany soep luxembourg psel united-kingdom bhps · · · a) source: social security programs through the world, http://www.ssa.gov/policy/docs/progdesc/ssptw/ b) echp - table : replacement rates (rr) - men. my elaborations on echp. panel approacha cross-sectional approachb denmark % % the netherland % % belgium % % france % % ireland % % italy % % greece % % spain % % portugal % % austria % % finland % % germany soep % % luxembourg % % united-kingdom % % a) median rr calculated as first pension on last wage (panel approach). b) rr calculated as mean pension for individuals aged - /mean labor income for individuals aged - (cross-sectional approach). table : mean educational level (average isced) - men mean isced all + denmark . . netherlands . . belgium . . france . . ireland . . italy . . greece . . spain . . portugal . . austria . . finland . . germany soep . . luxembourg psel . . united-kingdom bhps . . t a b le : w a g e re g re ss io n s d e n m a r k t h e n e th e r la n d s b e lg iu m f r a n c e ir e la n d it a ly g r e e c e s p a in p o r tu g a l a u s tr ia f in la n d g e r m a n y l u x e m b o u r g u k a g e - . - . - . - . . * * . * * * . * * * . * * * - . * * - . - . - . . - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) g o o d h e a lt h . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * — . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) d is a b le d - . - . . - . * * * . - . * * - . * * - . * * * - . * * * - . - . * - . * * * — - . * * 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* * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) c o h - . * * * - . * * * - . * * * - . * * * - . * * * - . - . * * * - . * * * - . * * * - . * * * - . * - . * * * - . * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) c o h - . * * * - . * * * - . * * * - . * * * - . * * * - . - . - . * * * - . * * * - . * * * - . * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a g e * c o h . * * * . * * * . * * * . * * * . * * * . . * * * . * * * . * * * . * * * . * * . . . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a g e * c o h . * * * . * * * . * * * . * * * . * * * . . * * * . * * * . * * * . * * * . * . * * * . . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a g e * c o h . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a g e * c o h . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) r e ti r in g * c o h - . . - . - . * * * - . . . * * * - . . * * . . . - . * - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) r e ti r in g * c o h - . * * . * . - . - . - . - . - . * * * - . - . - . . - . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) r e ti r in g * c o h - . — — . — - . * * * . — - . * * * - . - . — - . * * — ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) r e ti r in g * c o h — — — — — - . * * — — - . — — — - . * * * — ( . ) ( . ) ( . ) r -s q u a r e d . . . . . . . . . . . . . . n n o te s : d a t a e c h p fo r t h e p e r io d - . f o r g e r m a n y , l u x e m b o u r g a n d t h e u k w e u s e t h e s u r v e y s e c h p b a s e d o n t h e n a t io n a l s u r v e y s s o e p , p s e l l a n d b h p s r e s p e c t iv e ly . our papers can be downloaded at: http://cerp.unito.it/index.php/en/publications cerp working paper series n° / giovanni mastrobuoni filippo taddei age before beauty? productivity and work vs. seniority and early retirement n° / maarten van rooij annamaria lusardi rob alessie financial literacy, retirement planning, and household wealth n° / luca beltrametti matteo della valle does the implicit pension debt mean anything after all? n° / riccardo calcagno chiara monticone financial literacy and the demand for financial advice n° / annamaria lusardi daniel schneider peter tufano financially fragile households: evidence and implications n° / adele atkinson flore-anne messy assessing financial literacy in countries: an oecd pilot exercise n° / leora klapper georgios a. panos financial literacy and retirement planning in view of a growing youth demographic: the russian case n° / diana crossan david feslier roger hurnard financial literacy and retirement planning in new zealand n° / johan almenberg jenny säve-söderbergh financial literacy and retirement planning in sweden n° / elsa fornero chiara monticone financial literacy and pension plan participation in italy n° / rob alessie maarten van rooij annamaria lusardi financial literacy, retirement preparation and pension expectations in the netherlands n° / tabea bucher-koenen annamaria lusardi financial literacy and retirement planning in germany n° / shizuka sekita financial literacy and retirement planning in japan n° / annamaria lusardi olivia s. mitchell financial literacy and retirement planning in the united states n° / annamaria lusardi olivia s. mitchell financial literacy around the world: an overview n° / agnese romiti immigrants-natives complementarities in production: evidence from italy n° / ambrogio rinaldi pension awareness and nation-wide auto-enrolment: the italian experience n° / fabio bagliano claudio morana the great recession: us dynamics and spillovers to the world economy n° / nuno cassola claudio morana the -? financial crisis: a money market perspective n° / tetyana dubovyk macroeconomic aspects of italian pension reforms of s n° / laura piatti giuseppe rocco l’educazione e la comunicazione previdenziale - il caso italiano n° / fabio bagliano claudio morana the effects of us economic and financial crises on euro area convergence n° / annamaria lusardi daniel schneider peter tufano the economic crisis and medical care usage n° / carlo maccheroni tiziana barugola e se l’aspettativa di vita continuasse la sua crescita? alcune ipotesi per le generazioni italiane - n° / riccardo calcagno mariacristina rossi portfolio choice and precautionary savings n° / flavia coda moscarola elsa fornero mariacristina rossi parents/children “deals”: inter-vivos transfers and living proximity n° / john a. list sally sadoff mathis wagner so you want to run an experiment, now what? some simple rules of thumb for optimal experimental design n° / mathis wagner the heterogeneous labor market effects of immigration n° / rob alessie michele belloni retirement choices in italy: what an option value model tells us n° / annamaria lusardi olivia s. mitchell vilsa curto financial literacy among the young: evidence and implications for consumer policy n° / annamaria lusardi olivia s. mitchell how ordinary consumers make complex economic decisions: financial literacy and retirement readiness n° / elena vigna mean-variance inefficiency of crra and cara utility functions for portfolio selection in defined contribution pension schemes n° / maela giofré convergence of emu equity portfolios n° / elsa fornero annamaria lusardi chiara monticone adequacy of saving for old age in europe n° / margherita borella flavia coda moscarola microsimulation of pension reforms: behavioural versus nonbehavioural approach n° / cathal o’donoghue john lennon stephen hynes the life-cycle income analysis model (liam): a study of a flexible dynamic microsimulation modelling computing framework n° / luca spataro il sistema previdenziale italiano dallo shock petrolifero del al trattato di maastricht del n° / annamaria lusardi peter tufano debt literacy, financial experiences, and overindebtedness n° / carolina fugazza massimo guidolin giovanna nicodano time and risk diversification in real estate investments: assessing the ex post economic value n° / fabio bagliano claudio morana permanent and transitory dynamics in house prices and consumption: cross-country evidence n° / claudio campanale learning, ambiguity and life-cycle portfolio allocation n° / annamaria lusardi increasing the effectiveness of financial education in the workplace n° / margherita borella giovanna segre le pensioni dei lavoratori parasubordinati: prospettive dopo un decennio di gestione separata n° / giovanni guazzarotti pietro tommasino the annuity market in an evolving pension system: lessons from italy n° / riccardo calcagno elsa fornero mariacristina rossi the effect of house prices on household saving: the case of italy n° / harold alderman johannes hoogeveen mariacristina rossi preschool nutrition and subsequent schooling attainment: longitudinal evidence from tanzania n° / maela giofré information asymmetries and foreign equity portfolios: households versus financial investors n° / michele belloni rob alessie the importance of financial incentives on retirement choices: new evidence for italy n° / annamaria lusardi olivia mitchell planning and financial literacy: how do women fare? n° / flavia coda moscarola women participation and caring decisions: do different institutional frameworks matter? a comparison between italy and the netherlands n° / radha iyengar giovanni mastrobuoni the political economy of the disability insurance. theory and evidence of gubernatorial learning from social security administration monitoring n° / carolina fugazza massimo guidolin giovanna nicodano investing in mixed asset portfolios: the ex-post performance n° / massimo guidolin giovanna nicodano small caps in international diversified portfolios n° / carolina fugazza maela giofré giovanna nicodano international diversification and labor income risk n° / maarten van rooij annamaria lusardi rob alessie financial literacy and stock market participation n° / annamaria lusardi household saving behavior: the role of literacy, information and financial education programs (updated version june : “financial literacy: an essential tool for informed consumer choice?”) n° / carlo casarosa luca spataro rate of growth of population, saving and wealth in the basic life-cycle model when the household is the decision unit n° / claudio campanale life-cycle portfolio choice: the role of heterogeneous under- diversification n° / margherita borella elsa fornero mariacristina rossi does consumption respond to predicted increases in cash-on- hand availability? evidence from the italian “severance pay” n° / irina kovrova effects of the introduction of a funded pillar on the russian household savings: evidence from the pension reform n° / riccardo cesari giuseppe grande fabio panetta la previdenza complementare in italia: caratteristiche, sviluppo e opportunità per i lavoratori n° / riccardo calcagno roman kraeussl chiara monticone an analysis of the effects of the severance pay reform on credit to italian smes n° / elisa luciano jaap spreeuw elena vigna modelling stochastic mortality for dependent lives n° / giovanni mastrobuoni matthew weinberg heterogeneity in intra-monthly consumption. patterns, self- control, and savings at retirement n° / john a. turner satyendra verma why some workers don’t take (k) plan offers: inertia versus economics n° / antonio abatemarco on the measurement of intra-generational lifetime redistribution in pension systems n° / annamaria lusardi olivia s. mitchell baby boomer retirement security: the roles of planning, financial literacy, and housing wealth n° / giovanni mastrobuoni labor supply effects of the recent social security benefit cuts: empirical estimates using cohort discontinuities n° / luigi guiso tullio jappelli information acquisition and portfolio performance n° / giovanni mastrobuoni the social security earnings test removal. money saved or money spent by the trust fund? n° / andrea buffa chiara monticone do european pension reforms improve the adequacy of saving? n° / mariacristina rossi examining the interaction between saving and contributions to personal pension plans. evidence from the bhps n° / onorato castellino elsa fornero public policy and the transition to private pension provision in the united states and europe n° / michele belloni carlo maccheroni actuarial neutrality when longevity increases: an application to the italian pension system n° / annamaria lusardi olivia s. mitchell financial literacy and planning: implications for retirement wellbeing n° / claudio campanale increasing returns to savings and wealth inequality n° / henrik cronqvist advertising and portfolio choice n° / john beshears james j. choi david laibson brigitte c. madrian the importance of default options for retirement saving outcomes: evidence from the united states n° / margherita borella flavia coda moscarola distributive properties of pensions systems: a simulation of the italian transition from defined benefit to defined contribution n° / massimo guidolin giovanna nicodano small caps in international equity portfolios: the effects of variance risk. n° / carolina fugazza massimo guidolin giovanna nicodano investing for the long-run in european real estate. does predictability matter? n° / anna rita bacinello modelling the surrender conditions in equity-linked life insurance n° / carolina fugazza federica teppa an empirical assessment of the italian severance payment (tfr) n° / jay ginn actuarial fairness or social justice? a gender perspective on redistribution in pension systems n° / laurence j. kotlikoff pensions systems and the intergenerational distribution of resources n° / monika bütler olivia huguenin federica teppa what triggers early retirement. results from swiss pension funds n° / chourouk houssi le vieillissement démographique : problématique des régimes de pension en tunisie n° / elsa fornero carolina fugazza giacomo ponzetto a comparative analysis of the costs of italian individual pension plans n° / angelo marano paolo sestito older workers and pensioners: the challenge of ageing on the italian public 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governance: the case of uk pension funds n° / vincenzo andrietti and vincent hildebrand pension portability and labour mobility in the united states. new evidence from the sipp data n° / hans blommestein ageing, pension reform, and financial market implications in the oecd area n° / margherita borella social security systems and the distribution of income: an application to the italian case n° / margherita borella the error structure of earnings: an analysis on italian longitudinal data n° / flavia coda moscarola the effects of immigration inflows on the sustainability of the italian welfare state n° / vincenzo andrietti occupational pensions and interfirm job mobility in the european union. evidence from the echp survey n° / peter diamond towards an optimal social security design n° / emanuele baldacci luca inglese le caratteristiche socio economiche dei pensionati in italia. analisi della distribuzione dei redditi da pensione (only available in the italian version) n° / pier marco ferraresi elsa fornero social security transition in italy: costs, distorsions and (some) possible correction n° / guido menzio opting out of social security over the life cycle introduction the economy the definition of the competitive equilibrium the life cycle of human capital, the age profile of earnings and retirement empirical evidence differences in the age profile of earnings across european countries the relationship between the age profile of earnings and retirement rules conclusions and future developments bibliography page of beautiful burials, beautiful skulls: the aesthetics of the egyptian mummy the american egyptologist herbert e. winlock often livened up his annual excavation reports with a colourful turn of phrase. even so, ‘atrocities of hideousness’ stands out in his description of several burials he and his metropolitan museum of art colleagues discovered beneath the dramatic cliffs of deir el-bahri in the s (fig. ). sited on the west bank of the nile at luxor, deir el-bahri shelters temples of the middle and new kingdoms (c. to bce), which were the primary interest of the metropolitan expedition. one of the inconveniences of archaeology, however, is that later things lie in the way of earlier material, where stratigraphic deposits have accrued over time. archaeology took more interest in the remains of egypt’s glory days under famous pharaohs than in the centuries when egypt was part of the roman empire. while winlock’s team recorded these later burials with the same diligence devoted to other finds, his negative judgement of their aesthetic qualities reflects widespread ideas in th-century scholarship about the comparative value of ‘provincial’ roman art or the ‘decline’ of ancient egyptian art from its earlier pinnacle. laid directly in the ground, these wrapped-up mummies and their staring covers, painted on coarse-weave, gessoed linen, looked impoverished as well as hideous. plaster jewels were poor imitations of byzantine splendour, ancient gods appeared in cartoonish style at the bottom of each cover, and white, black, red, and yellow dominated the colour palette, a drab desert of painterly skill. today, one of the few intact examples of these rd-century ad mummies rests in a display case in the metropolitan museum of art, after several decades in storage. while still in the field, the museum unwrapped the other mummies it found, documenting the removal of h. e. winlock, hthe museum's excavations at thebes’h bulletin of the metropolitan museum of art, part ii, the egyptian expedition - ( ), - , at . for the burials, see christina riggs, ‘iggsstinaurials, seepoldeir el-bahri’, journal of egyptian archaeology ( ), - ; the beautiful burial in roman egypt: art, identity, and funerary religion. oxford: oup, , - , - . for a full-colour image of the intact mummy in the metropolitan museum of art, see ‘mummy with a painted mask depicting a woman holding a goblet’, the collection online accessed november . http://www.metmuseum.org/collection/the-collection-online/search/ page of the wrappings stage by stage in photographs and likely discarding both the textiles and the human remains afterwards. archaeological records are silent on such details, and mummies have the distinction of being the only discovery that archaeologists have consistently dismantled and destroyed in the process of their work. to modern science (and in the late th and early th centuries, archaeology self-consciously styled itself as a science in anglophone scholarship, more strongly than cognate knowledge formations), the primary value of a mummy was in the human corpse beneath the wrappings. surfaces – especially surfaces as unprepossessing as the deir el-bahri covers – offered little interest on either academic or aesthetic grounds. instead, the body inside held an aesthetic fascination of its own, thanks to the mummy’s trajectory through anatomical study, gothic fiction, and forensic science. the egyptian mummy thus exemplifies the gulf between any ancient aesthetic we can recover through archaeological evidence, and a modern aesthetic with tenacious roots in the colonial encounter between europe and egypt. in this article, i use egyptian burials of the roman period as an entry point for considering aesthetics in relation to archaeology, ancient art, and human remains. although some archaeologists and egyptologists reject the concept of aesthetics, even the word itself, i argue that a more rounded and reflexive approach to aesthetics in fact complements questions of ontology, materiality, and social practice that concern much contemporary archaeological thought. this in turn allows disparate sources of evidence or method – fieldwork, philology, visual analysis – to work together to try to apprehend ancient motivations and experiences. moreover, engaging with aesthetics requires archaeologists and egyptologists to reflect critically on disciplinary histories and the legacies they carry. more hideous than winlock’s ‘bedizened’ dead of deir el-bahri is the egyptian mummy’s long embedding in the discursive strategies of racial science, for instance, which this article concludes by contrasting with evidence for the aesthetics of funerary practice in roman egypt. beautiful burials and beautiful skulls lie on either side of the gulf between ancient page of experiences and modern expectations of what an egyptian mummy is, and is for. understanding these as the products of two different aesthetic frameworks shaped by distinct cultures may offer the best way to bridge them. i. aesthetics, archaeology, ancient art many specialists in ancient art either avoid the words ‘aesthetic’ and ‘aesthetics’ or use them chiefly in relation to visual perception and the communicative or expressive potential of form. archaeologists have also tended to reject aesthetics as too laden with western notions of fine art or refined taste, with their ready assumptions of cultural superiority and elitism. while both perception and the role of form have conventionally been foci of analytic aesthetics in philosophy, the past twenty-five years have seen anthropologists, archaeologists, and ancient art historians, along with philosophers, develop a much broader, less ethnocentric concept of aesthetics that moves beyond subject-object binaries to consider a full range of sensory encounters and engagements with the material world. building on the work of anthropologists jeremy coote and anthony shelton, archaeologist chris gosden has called for an understanding of aesthetics as part of the social life of objects, that is, the ways in which objects enable social relationships, the creation and maintenance of social structures, and the circulation and negotiation of social norms. sensory experiences, hence aesthetic values, are culturally directed. they derive not from the self-contained, perceiving subject, nor from the object or artwork itself (which is, after all, a cultural creation embedded in experiences), but from our interactions with the material world and – through materiality – the immaterial world as well. in cognitive archaeology, lambros malafouris has argued that an emphasis on one such argument within philosophy is alan h. goldman, ‘old broad view of aesthetic experience’, the journal of aesthetics and art criticism : ( ), - . jeremy coote and anthony shelton (eds), anthropology, art and aesthetics (oxford: clarendon, ); chris gosden, ‘osden: sense: archaeology and aesthetics’, world archaeology : ( ), - ; ‘aesthetics, intelligence and emotions: implications for archaeology’, in elizabeth demarrais, chris gosden and colin renfrew (eds), rethinking materiality: the engagement of mind with the material world (cambridge: mcdonald institute for archaeological research, ), - . page of material engagement offers a corrective to the overly narrow conception of aesthetics dismissed, or misconstrued, by some archaeologists and anthropologists of art. two examples may be useful here to illustrate the vexed relationship between aesthetics and the study of archaeology and ancient art. the first stems from my own experience, writing recently for an editor trained in classical archaeology, who questioned my use of the phrase ‘aesthetic preferences’ in a discussion of sculpture in roman egypt; wouldn’t ‘stylistic’ be a better choice than ‘aesthetic’? i held out for aesthetic, because judgements about the ‘style’ of an artwork are judgements that we make, in hopes that they will help us better characterize differences and similarities among our incomplete, self- defined corpus. what i was suggesting was that certain sculptural features were actors’ choices that could be understood as part of a wider aesthetic system rather than simply parsed as x indicates y, as if an arsenal of academic terms – iconography, style, context – could protect us from the pitfalls of our own admiration, or winlock-like revulsion, for our objects of study. my second example is a recently published reference work on ancient egyptian art, in which just three (of twenty-seven) contributions explicitly consider aesthetics. contributions to the volume use little or no comparative or theoretical literature, including what seem to this author to be established and significant scholarly voices in the archaeology and anthropology of art. for instance, only one contribution cites coote and shelton’s volume (required reading on anthropology syllabi for twenty years, and well-known to many archaeologists); none refers to gosden or other archaeological theorists and ancient art historians engaged with questions of aesthetics, such as zainab bahrani. instead, a lambros malafouris, ‘the aesthetics of material engagement’, in riccardo manzotti (ed.), situated aesthetics: art beyond the skin (exeter: imprint academic, ), - ; see also his how things shape the mind: a theory of material engagement (boston and london: the mit press , ). melinda k. hartwig (ed.), a companion to ancient egyptian art (malden, ma and oxford: wiley blackwell, ). bahrani’s relevant work includes the graven image: representation in babylonia and assyria (philadelphia: university of pennsylvania press, ); the infinite image: art, time and the page of contribution on ‘reception and perception’, which includes a section on aesthetics, proffers an internal dialogue between author alexandra verbovsek’s own and other egyptologists’ work, and uses a narrow idea of aesthetics focused on questions of beauty and formal effect. a second contribution on ‘style’, by editor melinda hartwig, similarly conjoins aesthetics and ‘the formal aspects of a work of art’. the contribution that does point readers to coote and shelton’s work, by egyptologist john baines, opens the volume by posing the ontological question ‘what is art?’. that this question needed its own chapter, in a volume devoted to art, speaks to the crisis of confidence that seems to dog the study of visual and material culture in egyptology, and to the insularity of egyptian art studies in comparison to ancient greek, roman, and near (or middle) eastern art. baines’ answer to ‘what is art?’ is to take ‘the aesthetic’ as his basis for interrogating the context, creation, and performative enactment of art in ancient egypt; in this way, he aims for a broader, more inclusive scope than that adopted elsewhere in the same volume. as he points out, the material record recovered through – i would say, created by – archaeology is a starting point, but apprehending the full significance of aesthetic concerns in ancient society requires us to think beyond that record, to the kinds of experiences that do not necessarily survive in a physical state. western theories of art, especially since the th century, have defined ‘art’ as something – a book, a piece of music, a painting – that produces an aesthetic effect or experience because it has been designed to do so. this culturally specific definition, often assumed to parallel ancient greek categorizations, arguably reduces ‘the ancient world’ aesthetic dimension in antiquity (reaktion/university of chicago press, ); and ‘assyro-babylonian aesthetics’, in michael kelly (ed.), the oxford encyclopaedia of aesthetics, nd edn (oxford: oup, ). perhaps tellingly, editors have not included an entry concerned with ancient egyptian aesthetics in either edition of the oxford encyclopaedia of aesthetics. alexandra verbovsek, ‘reception and perception’, in hartwig (ed.), companion to ancient egyptian art, - , section on aesthetics at - . melinda k. hartwig, ‘style’, in hartwig (ed.), companion to ancient egyptian art, - , quoted passage at . hartwig situates her discussion of style within semiotics and communications theory, rather than the extensive literature on style in art history, archaeology, and philosophy, on which see the overview by stephanie ross, nie . hartwig in jerrold levinson (ed.), the oxford handbook of aesthetics (oxford and new york: oup, ), - . john baines, ‘what is art?’, in hartwig (ed.), companion to ancient egyptian art, - . page of to a literate male elite in classical athens. beyond plato’s cave, the misapprehension of aesthetics as a matter of visual perception, or a standard of beauty, owes as much to th and early- th century philosophy (baumgarten, kant, hegel) as it does to the enduring influence of clive bell’s ‘significant form’. the formulation of a modernist aesthetic coincided with important publications on egyptian art (e.g. by heinrich schäfer and jean capart) and with changes in collecting and display practices in the early th century. as with ethnographic art, non-western art from the distant past seemed to invite connoisseurial appraisal, ‘elevating’ it to the status of ‘art’ in western mode and separating it from questions of context and provenance that had been archaeology’s defining characteristic. today, neuroaesthetics and other scientistic approaches to art and aesthetics often echo the easy universalism of ‘significant form’, especially when generalizing from a few restricted examples, as if the chauvet cave and picasso were unproblematically sublime. like gosden and malafouris, i see the relationship between the artwork and its aesthetic values as inherently fluid, created as it is within social, material, and historical networks. an object develops aesthetic qualities because of what it does, not (or not only) because of how it looks, and the ontology of the object likewise incorporates this social and temporal dimension. as bahrani argues for ancient mesopotamian art, a statue in human-like form functioned as a representation not through mimetic resemblance, which has been a this is the approach in james o. young, ‘the ancient and modern system of the arts’, british journal of aesthetics : ( ), - , for instance. for an alternative view (with a broader perspective than young, whose focus is paul oskar kristeller’s study the modern system of the arts), see larry shiner, the invention of art: a cultural history (chicago: university of chicago press, ). discussion of the ancient greek evidence: jeremy tanner, ىئ ېئ 辏﻾﻾ب椐 and art history writing in comparative historical perspective’, arethusa : ( ), - ; the invention of art history in ancient greece: religion, society and artistic rationalisation (cambridge: cambridge university press, ). schäsch’scvon ägyptischer kunst (leipzig: j. c. hinrich, ), influential in german-speaking egyptology, was translated into english in by john baines. capart’s leeipz sur l’art égyptien (liége: vaillant-carmanne, ), which includes a chapter ‘problems of egyptian aesthetics’, appeared in english in . capart’s work was influential in defining and promoting prehistoric (predynastic) egyptian objects as ‘primitive art’ in the early th century. the work of two leading proponents of neuroaesthetics, semir zeki and v. s. ramachandran, is discussed in john hyman’s cogent critique, ‘art and neuroscience’, in roman frigg and matthew hunter (eds), beyond mimesis and convention: representation in art and science (dordrecht: springer, ), - . page of primary concern of western art, but through an un-real resemblance that used the material world to look beyond the material, and beyond the horizon of human time. egyptian art, too, had another audience in mind, not an embodied viewer who could stand, like we do, in front of a tomb painting and ‘read’ its messages, or bend over a museum display case to weigh up the relative attractions of a painted mummy cover thick with plaster, pressed over an actual human body whose time horizon uncannily intersects ours. how, then, can those of us who study and interpret the past today acknowledge, identify, or retrieve the aesthetic experiences of an ancient culture, especially where those might seem so far removed from our own? perhaps the museum display case is an apt metaphor for this challenge, facilitating as it does our unimpeded vision across a gulf of time, place, and being. yet if we do not at least attempt to recover something of ancient aesthetic concerns, we do ourselves and our objects of study a disservice. the archaeological object demands and deserves aesthetic consideration on as near as we can get to its own terms, not only as an approach to modelling the ancient past, but as a corrective to our own aestheticization of that past, which may be diametrically opposed. aesthetics need not, and should not, be an etic exercise, the outsider always looking in through the distancing glass. archaeological evidence does offer ways to see insiders looking at themselves, and in the next section, i return to the burials of roman egypt to consider how enactment, form, and materiality can each help us apprehend the aesthetics of ancient funerary practices. ii. beautiful burials one reason for winlock’s dismissive attitude to the third-century ad burials at deir el-bahri was the relative simplicity of their deposition, compared to earlier egyptian practice. however, the enactment of burials was always more varied than the presumed egyptian norm bahrani, infinite image, esp. at - , but the discussion is sustained throughout the volume. page of of a rock-cut or constructed tomb with an exterior chapel or commemorative marker; this was a norm only for certain elites at certain periods and places. throughout egyptian antiquity, some forms of corpse disposal either left no archaeological trace or have not been recovered through excavations to date. the roman burials at deir el-bahri were laid directly in the ground in shallow pits, either individually or in small groups. apart from the wrapping and adornment of the embalmed body, and a basket or broken amphora placed over the head of a few burials, nothing else was found in the graves. in the roman period, this pattern of deposition was not uncommon. grave goods were minimal, and bodies were often cached in communal tombs overseen by cemetery caretakers, some of whom combined the roles of administrators, gravediggers, and ritualists. depending on the locale, burials were made in simple pits or in fresh, purpose-built tombs cut into cliffs or bedrock, or else they might be inserted into much older tombs, reclaiming and reusing venerated space. some cemeteries associated with urban centres did have tomb superstructures, with bodies placed under the floor or set into niches, but these appear to have been more rare, or at least not as well preserved. in thinking about funerary practices in roman egypt, then, one of the first points to acknowledge is that communal burial was widely practiced, and even individual graves were dug in close proximity to each other, sometimes overlapping earlier burials. even if the specific deposition of the corpse was a decision left to cemetery workers, rather than the mourners, communality and simplicity (as we might characterize the paucity of grave goods) must have had a positive, or at least neutral, aesthetic value. john baines and peter lacovara, ‘burial and the dead in ancient egyptian society: respect, formalism, neglect’, journal of social archaeology ( ), - . tomasz derda, rdasz)of social archaeograeco-roman egypt in the light of the greek papyri’, journal of juristic papyrology ( ), - . for example, katja lembke, ‘city of the dead: tuna el-gebel’, in christina riggs (ed.), the oxford handbook of roman egypt (oxford: oup, ), - . practices varied over time and by region, but for the cemetery workers known as choachytes, active in the theban region in the ptolemaic period, see p. w. pestman, the archive of the theban choachytes (leuven: peeters, ). page of moreover, in egyptian practice, the enactment of a burial extended both before and beyond the deposition of the body. the ideal length of time devoted to embalming and wrapping a corpse was seventy days, correlated in ritual texts to the length of time the decan constellations were visible in the night sky. although not every body received a complete mummification, by any means, some form of embalming enabled a prolonged performance of mortuary and mourning activities. gaps of days, weeks, or many months could pass between the time the mummy was prepared and the date when it was placed in the grave or tomb, suggesting that a separation of ritual activities was not unusual. papyrological documents hint at stages such as an initial washing and laying out of the body at home, delivery to the embalmers three or four days after death, and a funeral banquet and procession, but it is difficult to say anything much more precise. what scholars can say is that funerary practices reflect and enable an array of aesthetic choices, which are not about ‘providing for the afterlife’ in the rather simplistic way that much egyptological literature and museum displays would have it. they are also not so much about the preservation of a bounded individual identity but about the commemoration, and re-creation, of a social one, a caveat that applies all the more so where certain individuals were singled out for particular care in terms of the embalming and wrapping of the body and its adornment with masks, shrouds, or coffins. such examples are exceptional, but nevertheless, they can help us understand the sensory, visual, and material world that produced them, and thus, the ancient actors’ aesthetic intent. maarten j. raven, ‘egyptian concepts on the orientation of the human body’, journal of egyptian archaeology ( ), – (at – ). relevant discussion in walter scheidel, ‘the meaning of dates on mummy labels: seasonal mortality and mortuary practice in roman egypt’, journal of roman archaeology ( ), – . for an overview of such practices, using greek-language evidence from the period, see dominic montserrat, ‘ontserratrview of such practicesfayum’, in m. l. bierbrier (ed.), portraits and masks (london: british museum press, ), - . thus also alice stevenson, ‘tevenson alice mupredynastic egyptian burial: funerary performances in the th millennium bc’, archaeological review from cambridge : ( ), – . page of from a different site and an earlier date, another roman-period burial in the metropolitan museum of art exemplifies this exceptionality: even winlock could not have characterized the mummy of artemidora as hideous, with its gilded adornments, rich colours, and plaster mask, moulded to resemble a lifelike head (fig. ). the naturalistic mask and a greek epitaph at the foot end of the mummy, identifying the deceased as ‘artemidora, daughter of sarapion, died untimely aged ’, lend this body a more immediate impact, to modern eyes, than the wrapped body from deir el-bahri, and to some extent, this distinction reflects differences in social status and milieu. unlike the deir el-bahri burials, which are drawn from a village population in the south of egypt, the mummy of artemidora was found in a communal tomb at meir in middle egypt, a cemetery that served a provincial town nearby, in a region better connected to trade and commerce and more intensively settled over the centuries by immigrants from the greek world. in terms of the performance and enactment of funerary rites, artemidora’s mummy probably shares much in common with the mummy from deir el-bahri, but as a more elaborate example, i use it here to address two further insights it may offer into an ancient aesthetic system, which i discuss in terms of form and materiality. to start with the question of form – whose concern with outer surface and shape has vexed so much discussion of aesthetics – let us consider first the distinctive shape of the mummy, with its smooth and rounded contours; tall, shaped foot end; and masked head end. the same form is attested for other wrapped mummies and wooden coffins, all from the region of middle egypt between the fayum basin and asyut, and all dating to the st and nd centuries ad. the exaggerated foot end, which stands nearly a metre high on the artemidora example, is matched by the extended length of the entire mummy, which, at almost two christina riggs, the beautiful burial in roman egypt: art, identity, and funerary religion (oxford oup, ), - . for full-colour images, see ‘mummy of artemidora’, the collection online accessed november . see riggs, beautiful burial, - passim, - ; dieter kurth, der sarg der teüer : eine studie zum totenglauben im römerzeitlichen Ägypten (mainz: philipp von zabern, ). http://www.metmuseum.org/collection/the-collection-online/search/ page of metres, is almost a third longer than the corpse itself. most of what we see comprises some hundreds of metres of linen textiles layered and wrapped around the body inside, so that the corpse becomes an inner core deep within a sacred bundle. these textiles, which were essential to the ritual of mummification, linked the deceased’s lifecycle to his or her family and community, comprising as they did clothing and household linen owned by the dead person and donated by family and associates. only pure linen could be used as wrapping material, and by preference cloth that had not been dyed or decorated. where linen had to be purchased for a burial, the expense represented a substantial outlay, perhaps ten times the annual earnings of a skilled craftsman. on the mummy of artemidora, the padded, bulky form of the wrappings created the tall foot projection as well as a head end curved exactly to fit into the hollow of the richly gilded, painted, and inlaid mask. the embalmers and mask-makers must have worked in tandem to create this effect, likewise the smaller pieces of stuccoed linen that decorate the sides and foot area of the wrappings. the mask itself represents artemidora in contemporary clothing, heavy jewellery, and a roman imperial hairstyle, which merges with the luxuriant long curls of an egyptian goddess to emphasize the divine qualities that mummification brought out in the dead. around the sides and back of the mask, a procession of gods culminates at the crown of the head with the resurrection of osiris, the god-king whose death and embalming anchored egyptian funerary mythology. the content and design of this composition makes clear reference to temple decoration; similarly, the tall foot end of the mummy, with its curved and flared upper edge, echoes the shape of shrine roofs and commemorative stelae. at each end of the mummy, the outer forms thus create their own sacred structure around the body, in effect providing a tomb for the wrapped or coffined mummy even in a communal space such as the one where artemidora was buried. these architectonic forms and decorative references also for the use and significance of textiles in mummification, see christina riggs, unwrapping ancient egypt (london: bloomsbury, ), - , - . page of treat the wrapped body like the sacred image it is, since egyptian statues of the gods were kept in shrines even when carried outside the temple for festival processions. the formal aspects of a burial cannot be separated from this wider network of associations, or from the processes that yield its outer form, such as the supply and wrapping of the textiles. this does not deny that visual splendour was also part of a burial’s effectiveness. in the ancient egyptian language, a burial was often described as either menkhet, ‘effective’ or neferet, ‘beautiful’, with an interchangeability suggesting that the two expressions convey similar qualities. a wrapped mummy and its accoutrements – masks, shrouds, coffins – were manifestations of the deceased as something not-of-this-world, created within a set of practices contingent upon the individual’s being and relationships in- this-world. hence questions of form lead to a second, related insight into an ancient aesthetic system, through questions of materiality. the deir el-bahri mummy may look drab in comparison to the mummy of artemidora, but both most must have transmitted some idea of beauty, through a visual splendour that we can access more equitably by paying closer attention to the materials used in their making. both the cover on the deir el-bahri mummy and the mask and placards on artemidora’s are made in the same way, by adhering coarse-weave linen with gesso and adding further plaster to achieve a sculptural effect. the faces of both were created by pressing them into a mould, to which other moulded elements were then added and hand-finished. the use of plasterwork for burial equipment increased during the roman period, for reasons that have never been explored in detail. an improved ability to make plaster (by firing limestone into lime) and to work with it may well have been involved, but the effects that plaster produced – naturalistic facial features, complex hair and jewellery patterns, a surface ready to paint or gild – may also asja müller, university of kiel, is undertaking a doctoral thesis on plaster mummy masks in roman egypt, which will help address this and other points about the use of this material. page of have struck a chord with contemporary representational preferences, perhaps influenced by the prestige of classical-style sculpture in the roman empire. plaster-and-linen masks like the artemidora example, or another female mask that has been removed from its mummy (fig. ), display the striking impact of colour and gilding. the latter example, which comes from the fayum cemetery of hawara, covers the skin and dress of the deceased with gold leaf. on the artemidora mask, the skin of the face and arms was originally a bright, gleaming white, to judge by similar coffins and masks; a modern coating appears to have darkened these surfaces. both gold and bright white conveyed a shining, almost supernatural, gleam, and both were used in egyptian art to represent the skin of gods. one of the most striking features of the artemidora mask is the rich red of the clothing; the gilded mask in fig. also deployed a deep purple on the tunic stripe, red on the floral bouquet, and bright pink on the back, where egyptian gods appear. rather than the red ochre-based pigments used in pharaonic egypt, these deep shades of red, purple, and pink are likely a form of red lead, a synthetic pigment, known as lake pigment, which was made using madder. lake pigments were innovations of this period, and the richer, more durable effects they allowed may have been one factor encouraging the predominance of pinks and reds in funerary art of this era – though the deir el-bahri cover reminds us that similar colour results could still be achieved with conventional pigments. pinks, reds, and purples were likely seen as contiguous, being shades of one colour (red) rather than the distinct colours marked by english vocabulary. for instance, ritual papyri of around this date refer to ‘dark red’ and ‘light for instance, in the paintings on a papyrus known as the great harris papyrus, in the collections of the british museum: pierre grandet, le papyrus harris i (bm ) (cairo: institut française d’archéologie orientale, ); photographs are accessible on the museum website. sophie rowe, ruth siddall, and rebecca stacey, ‘roman egyptian gilded cartonnage: technical study and conservation of a mummy mask from hawara ‘, in julie dawson, christina rozeik, and margot m. wright (eds), decorated surfaces on ancient egyptian objects: technology, deterioration and conservation (london: archetype ), – . page of red’ – maroon and pink, in contemporary english? – to describe bandages that the sister- goddesses isis and nephthys contributed to embalming. the use of colour and gilding is intrinsically linked to our visual apprehension of the finished object, but as with the textiles discussed above, the signifying role of different materials, colours, and methods of manufacture are just as important for understanding an aesthetic experience and value system quite different from that of modern societies steeped in western intellectual traditions. textiles, which wrapped the dead in an individual as well as a social identity, had visual and tactile qualities whose aesthetic appeal can be judged through the documentary evidence, such as the different grades applied to textiles; so-called royal linen was the most finely spun and woven. the outcome of wrapping rituals in the mummification process was only partly visible, however, with the outermost layer smoothed into the cocoon-like form used for mummies and most coffins since around bc. to be wrapped, as other sacred images were as well, was to be hidden, safe, and preparing for rebirth. the performance of wrapping was seen by no one but the responsible priests, and wrapped forms like the mummy, or its doubles in coffins and divine statues, thus exemplify what jan assmann has called an ‘aesthetics of secrecy’ in ancient egyptian culture. restrictions on viewing were part of this aesthetic system: there is no way to know for certain whether wrapped mummies were ever seen by mourners. if they were, it may only have been fleetingly during a funeral procession, and where a mummy was placed inside a coffin or covered by a catafalque. even those fleeting glimpses will have been further restricted by factors such as ritual roles, mourners’ relationship to the deceased (widows are shown embracing the coffin, for instance), and by the performance itself, with the crowds and e.g. mark smith, the mortuary texts of papyrus bm (london: british museum, ), column vi, lines - . jan assmann, ‘zur Ästhetik des geheimnisses: kryptographie als kalligraphie im alten Ägypten’y in aleida assmann and jan assmann (eds), schleier und schwelle, i: geheimnis und Öffentlichkeit (munich: wilhelm fink, ), – ; see also riggs, unwrapping, –ß . page of obscured sightlines any large gathering tends to entail. the aesthetic value of a work of art or other cultural practice need not correlate to its visibility. yet visibility – whether through the museum display case, or the ct-scanner – now dominates our aesthetic judgement of mummies and other archaeological objects. since the late th century, modern interpretations have transmuted the aesthetics of the egyptian mummy into an aesthetics not of beauty and of the secret, but of dissection, the forensic, and the relentlessly visible. in the final section of my discussion, i explore the history and legacy of this transmutation, which has turned beautiful burials into beautiful skulls. iii. beautiful skulls many museum collections of egyptian antiquities bear ample evidence that modern ideas about what a mummy is and is for are very different from ancient ones. from the early modern trade in powdered mumia to the penchant for grisly souvenirs, mummies and fragments of mummies have become part of larger narratives, about the individual presumed to have inhabited the body; about the archaeologists, scientists, or collectors associated with the remains, often in a colonial context; and about ancient egypt and the egyptian mummy as tropes of death, disease, danger, the erotic, and the exotic. but running through all these narratives is something at least as invidious as the cannibalism of mumia consumption or the dismemberment and commodification of human remains: it is the search for the beautiful skull. prior to the paradigm shift of the enlightenment, with its preference for the penetrating gaze, europeans were disinclined to unwrap egyptian mummies, which were rarities in collections until the turn of the th century. the founding collection of the british museum included small, intact mummies collected by sir hans sloane and sir william john frederick blumenbach, ‘lumenbacherick her references.e to the reviewer’s helpfulphilosophical transactions of the royal society london ( ), - . page of hamilton. these were revealed to be forgeries only in , when they were unwrapped by johann blumenbach, professor of medicine at göttingen, who presented his results to the royal society in london. composed of ancient linen neatly arranged around a core of animal or human bones, linen scraps, and debris, such mummies had been acquired in good faith as examples of mummification, because their external appearance matched what europeans had come to think of as ‘a mummy’, in the recognizable, smooth-sided form that was already well- documented. the absence of human remains inside the british museum mummies was a particular disappointment, because blumenbach’s chief aim was to make detailed measurements of skulls. his work laid down the fundamental principles of what would become physical anthropology, including the use of craniometry to develop the new concept of race. blumenbach’s doctoral thesis had characterized human ‘variety’ through five races, identified by skull shape and skin colour, or in his terms, caucasoid, mongolian, ethiopian, american, and malayan. the caucasoid group was so named after the caucasus mountains in georgia, where what he described as the most beautiful skull he had ever studied, that of a woman, had originated. blumenbach’s work was both the product and promoter of prevailing ideologies, which used race as one way of examining the bewildering differences that confronted europeans in colonial contact zones. in addition to whatever antiquarian or anatomical insights might be gained from examining mummies more closely, from the late th century onwards there was now another incentive for unwrapping egyptian mummies, whose preserved skin and bones held the promise of further data for the scientific classification of humankind. in the s, english-italian obstetrician augustus bozzi granville referred to blumenbach, dutch anatomist petrus camper, and leading french scientist georges cuvier in john frederick blumenbach, ‘lumenbacherick her references.e to the reviewer’s helpfulphilosophical transactions of the royal society london ( ), - . page of presenting his own unwrapping and dissection of an egyptian mummy to the royal society, concluding – like cuvier – that the egyptians were caucasian, like europeans. measurements of the skull and pelvis provided all the evidence needed; granville proved his point by measuring the facial angle of the mummy’s profile and comparing its pelvis to that of a ‘negro girl’ in his collection of anatomical preparations. as more mummies entered european collections after the end of the napoleonic wars and concomitant increase in trade and travel between egypt and the west, newly styled egyptologists such as george gliddon and showman-surgeons like thomas ‘mummy’ pettigrew turned mummy unwrappings into public spectacle, laying bare on the examination table what ancient egyptian aesthetics and cultural decorum had expected to remain intact and unseen. when archaeology emerged as a self-consciously scientific discipline in the late th century, it ostensibly rejected such showmanship. but the destruction – for that is what it was – of mummified bodies through anatomy continued both in the field and in the metropole. the characterization of race in ancient human remains was taken as given, using the techniques of physical anthropology and victorian race science. one of the most influential archaeologists working in egypt, w. m. flinders petrie, collected egyptian skeletal remains for the eugenics laboratory established by his friend francis galton at university college london, while petrie’s protégée, margaret murray, conducted two mummy unwrappings at the university of manchester in . augustus bozzi granville, ‘ra essay on egyptian mummies, with observations on the art of embalming among the ancient egyptians’, proceedings of the royal society of london ( ), - ; christina riggs, ‘an autopsic art: drawings of “dr granville’s mummy” in the royal society archives’, royal society notes and records , doi: . /rsnr. . [advance online publication]. on pettrigrew, see gabriel moshenska, shenskag“ shenskpettigrew and the study of egypt in early nineteenth-century britain’, in william carruthers (ed.), histories of egyptology: interdisciplinary measures (abingdon, uk: routledge, ), - . for gliddon, see robert j. c. young, ‘young, j. c. seeutblack athena’, in daniel orrells et al. (eds), african athena: new agendas (oxford: oxford university press, ), - , at - . for petrie and galton, see debbie challis, the archaeology of race: the eugenic ideas of francis galton and flinders petrie (london: bloomsbury, ); for the murray unwrappings, see samuel j. m. m. alberti, ‘molluscs, mummies and moon rock: the manchester museum and manchester science’, manchester region history review ( ), - , at - ); kathleen l. sheppard, ‘between spectacle and science: margaret murray and the tomb of the two brothers’, science in context : ( ): - ; riggs, unwrapping, - , - . page of although one of these unwrappings was a public event, attended by local grandees, university students, and the press, murray emphasized the rigour of the scientific methods applied to studying what was left of the fragile corpses. in the published results, a manchester physician contributed his conclusion that one of the skeletons was ‘negroid’ and ‘robust’, the other ‘caucasian’ and ‘effeminate’, this despite hieroglyphic inscriptions on the mummies’ coffins identifying them as brothers. murray and her colleagues knew better. the evaluation of egyptian mummies not for their exterior but for their interior is presumed to be a function of scientific advances, but i suggest that we can consider it instead as a question of aesthetics, whereby one aesthetic system has supplanted another, overwriting the values of an ancient culture with the aesthetic forms constitutive of scientific objectivity in our own. facial reconstructions of ancient egyptian mummies offer a contemporary case in point, based as they are in what human rights scholar thomas keenan and visual studies scholar eyal weizman have called a ‘forensic aesthetics’. since the s, techniques for reconstructing the fleshed appearance of a skull have proved to have criminological uses, for instance to help identify victims of murder or war crimes or, in the case keenan and weizman discuss, a perpetrator of such crimes, josef mengele. but forensic artists also applied these techniques to ancient human remains, first using physical skulls, and more recently ct-scanning, which allows wrapped bodies to be visualised without physically unwrapping them. the effects are the same, however, with the result that the aesthetic emphasis placed on egyptian mummies in museums and the media today focuses almost entirely on the physicality of the corpse – quite the opposite of the ancient actors’ intent. imaginative reconstructions take the study of skulls much further than blumenbach and on visualisation and objectivity in the sciences, see lorraine daston and peter galison, objectivity (brooklyn: zone books, ). thomas keenan and eyal weizman, mengele's skull: the advent of forensic aesthetics (berlin: sternberg press, ); riggs, unwrapping, - . caroline wilkinson, forensic facial reconstruction (cambridge: cambridge university press, ); john prag and richard neave. making faces: using forensic and archaeological evidence (london: british museum press, ). page of granville, or petrie and galton, could ever have anticipated, though all would recognize the discourse of race science in which such reconstructions are enmeshed. the recent reconstruction of two roman-period mummies at a canadian university museum offers a case in point (fig. ). the accompanying press release, picked up by websites such as livescience.org and discovery.com, adopts a passive voice that suggests scientific authority and defers responsibility for the inevitable questions of race such reconstructions raise: egyptian tissue depth data derived from ultrasonic imaging of modern egyptians were used to flesh out the faces. a diversity of skin tone is shown to reflect the mediterranean, north african, and sub-saharan mixture of the egyptian population as noted throughout history. hairstyles were pulled from earlier anthropology reports and detected through the wrappings worn by one of the mummies [emphasis added]. press coverage, the responsible artist, and, judging by its website, the museum’s own exhibition, all present such ‘data’ as unproblematic, likewise the technique itself. yet such facial reconstructions rely on soft tissue depth data that are often outmoded, and always open to interpretation, likewise judgements about what skin colour, age and gender features, and hairstyles or clothing to represent. photographs and videos of facial reconstructions in progress, with depth markers plugged into the modelling matrix, or of mummies being ct- a third mummy dated to around the st cent bc; strangely, the museum seems to have thought all three dated to the much earlier new kingdom. online coverage: neale mcdevitt, ‘facial reconstructions bring redpath mummies to life’ ; ‘the faces of egyptian mummies revealed’, < http://www.livescience.com/ -egyptian-mummy-facial-reconstructions.html>; jennifer viegas, ‘mummies’ faces, hairdos, revealed in d’ ; victoria lywood, ‘the mummies’ all accessed november . ‘p://sc life after death’, news release accessed november . redpath museum, ‘exhibits’, third floor, world cultures exhibits accessed november . see discussion in susan hayes, ‘ayesnscussion inember .h/node/ /exhibits /exhibits"hibits b̂. that is, there see page of brown and jennings ( ). is an extra weight on public information above and beyond its information value. apparently, b − b̂ = α α + ρ k + βm − α α + ρ + β > since k < and m < . moreover, because we have derived the explicit expressions of b and b̂, we can examine the properties of the keynesian-beauty-contest effect beyond its existence. this paper focuses on one of these other properties: how changes in the quality of public information affect the informativeness of stock prices as signals of the fundamental value. in a keynesian-beauty-contest stock market, the information role of public information makes the stock price a more accurate signal of the fundamental value, whereas the commonality role of public information drives the stock price away from the fundamental value. the overall impact of public information on market efficiency is thus a trade-off between these two opposing forces and the answer is not straightforward. for example, one extreme case is to eliminate the keynesian-beauty-contest effect by prohibiting public information. as α goes to zero, the weight on public information approaches zero in both the long- and short-horizon economies and the keynesian-beauty-contest effect vanishes. in this case, does the withdrawal of public information drive stock prices closer to the fundamental value? while investors put no weight on the noise in the public signal, they are now putting more weight on the supply noise. the net effect of withdrawing some noisy public information is therefore ambiguous. i formally study this issue in the rest of the paper. this is the case because d is decreasing in α. keynesian beauty contest and market efficiency while there are many metrics measuring market efficiency, i focus on price efficiency, the accuracy with which stock prices reflect the fundamental value (see tobin, , e.g). the primary goal of financial reporting is to provide various market participants with information about a business en- terprise’s fundamental value (see fasb, , e.g.). meanwhile, one basic function of markets, stock markets included, is to aggregate and disseminate value relevant information inherently dispersed among market participants (see hayek, , e.g.). to the extent that i examine the impact of the quality of accounting disclosure on the price discovery function of stock markets, price efficiency is a proper measure. by adhering to my definition of market efficiency, i try to avoid unnecessary confusion of terminology. in the theoretical literature on noisy rational expectations in capital markets, price efficiency is sometimes labeled as informational efficiency, as opposed to allocational efficiency based on pareto-efficiency in a general equilibrium (see brunnermeier, , e.g.). the label “informa- tional” is inevitably confused with the empirical definition of market efficiency by fama ( ). moreover, despite the possible divergence, two types of efficiency are closely related. in a much richer model, more accurate prices could enable market participants to make better informed deci- sions with respect to resource allocation. to that extent, price efficiency may also be viewed as a reduced-form counterpart of the pareto-efficiency-based definition of market efficiency, such as the one in grossman ( ). price efficiency is measured using the reciprocal of the mean-squared error (mse) between a firm’s fundamental value and its stock prices, a traditional measure of the extent to which markets hirshleifer ( ) provides an example of the possible divergence. fulfill the price discovery function. in statistical terms, price efficiency emphasizes on the efficiency property of stock prices as an estimator of the fundamental value. lower mse implies that stock prices are much closer to the fundamental value, resulting in higher market efficiency. p e = es,z[p − θ] ( ) pe is an ex ante measure. es,z[·] means that the expectation is taken with respect to both supply noise and public information. given the presence of the keynesian-beauty-contest effect, how could we improve market effi- ciency through accounting disclosure? proposition answers this question. proposition . more public information uniformly improves market efficiency, even in the pres- ence of the keynesian-beauty-contest effect. in the context of stock markets as a keynesian beauty contest, transparency is still a worthwhile cause. accounting disclosure provides information about the future cash flow of a firm. although short-horizon investors overuse it, provisions of more and better financial reporting still boost the overall informativeness of stock prices to market participants. the fact that stock markets behave like a keynesian beauty contest does not justify the withdrawal of public information. public information affects market efficiency through its dual role: the information role and the commonality role. the former improves price efficiency while the later potentially reduces price efficiency. in the absence of a formal examination of the relation between the two roles, we may conjecture that prohibition of some noisy public information may be necessary to enhance market efficiency in a keynesian-beauty-contest stock market. as public information becomes less precise, its information value is attenuated. if the commonality role increases or at least does not decrease in the variance of public information, there could exist a threshold of the precision of public information under which the diminishing information role is dominated by the non-decreasing commonality role. proposition contradicts such a conjecture. it implies that while public information plays the dual role, the information role always dominates the commonality role. since the information role dissipates as public information becomes less precise, a necessary condition for the dominance is that the commonality role decreases in the variance of public information. that is, the dual role of public information is endogenously linked through the quality of public information. i verify this intuition by showing that the keynesian-beauty-contest effect intensifies as public information becomes more accurate. before proceeding to the endogenous link between the dual role of public information, there is one caveat about proposition . the conclusion is obtained in a competitive equilibrium in which the action (demand) of any atomistic investor does not affect the price and thus the ac- tions (demands) of other investors. while this result establishes an important benchmark for the desirability of public information in a competitive market, there could be other channels through which public information reduces the overall informativeness of market prices. in this broad sense, shiller ( ) suggests that news media exert undue influence on market events by promulgating information and thus creating “similar thinking among large groups of people.” one prominent approach, which has been advanced lately and may substantiate shiller’s arguments, is to model explicit coordination motivations among agents. for example, plantin, sapra, and shin ( ) cre- ate explicit coordination issues among financial institutions by introducing the (il)liquidity of the market for selling financial assets. their selling decisions become strategic substitutes under the the august issue of the economist has a concise summary of the main effects in plantin, sapra, and shin regime of historical cost accounting, and strategic complements under the regime of mark-to-market accounting. by coordinating financial institutions’ selling decisions, mark-to-market accounting in- jects “endogenous” and “artificial” volatility to the market price, degrading its information value. thus, the attempt to use the information contained in prices destroys the information value of prices. although they do not model the impact of public information on market efficiency, their approach may be used to construct examples with different conclusions on the desirability of public information. in sum, proposition sets an important benchmark for the welfare effect of public information in a competitive market; it will be interesting to explore what kind of market frictions could change the conclusions in this benchmark case. bearing this caveat in mind, we resume the investigation of the relation between the dual role of public information to gain better intuition behind proposition . as discussed before, the keynesian-beauty-contest effect of stock market, the commonality role of public information, and the extra weight on public information in stock price are three equivalent concepts. using as the benchmark the weight on public information in the long-horizon economy, we could quantify the keynesian-beauty-contest effect as the discrepancy between the weights on public information in p and p̂ . i define the extra weight on public information, r, as follows. r = − b c / b̂ ĉ ( ) since the ratio b c ( b̂ ĉ ) reflects the relative use of public and private information when investors have short (long) horizons, the ratio b c / b̂ ĉ represents the extent to which public information is overused by short-horizon investors. the monotonic transformation in definition normalizes r to ( ). lie between zero and one. the greater r is, the more salient the keynesian-beauty-contest effect. proposition . the keynesian-beauty-contest effect intensifies as public information becomes more precise. since we have solved for the closed-form equilibrium, we can show here the determinant of the intensity of the keynesian-beauty-contest effect. the commonality role is connected to the information role through the quality of public information. when the quality of public information improves, the keynesian-beauty-contest effect becomes more salient and the price concentrates further on public information. the intuition for this link is straightforward. the keynesian- beauty-contest effect occurs because public information has information value in the first place. anticipating that other investors will be using public information to forecast the fundamental value, a short-horizon investor, who tries to forecast the consensus fundamental value, overuses public information over and above its optimal use in assessing the fundamental value. as it becomes more accurate, not only does she use public information more due to its improved information value, she also overuses it further because of its enhanced commonality role of forecasting the consensus fundamental value. just as morris and shin ( ) differentiate the keynesian-beauty-contest effect from the sunspot literature based on the fact that public information has the information role, the endogenous link between the dual role of public information is a hallmark of the rational keynesian-beauty-contest effect. this endogenous link between the information role and the commonality role of public informa- tion is crucial in the market efficiency consequences of public information. short horizons create interdependency of investors’ demands for stocks and give rise to the dual role of public informa- tion. the dual role is endogenously connected to each other in such a way that the commonality role is always secondary to the information role in terms of market efficiency. in contrast, if the dual role of public information is directly assumed, as opposed to being derived from short horizons, the endogenous link is then muted. consequently, when the information value is tenuous while the commonality role is strong enough, noisy public information could decrease market efficiency. morris and shin ( ) prove a similar point. in their game theory model, besides a standard component of utility defined over the distance between her action and the true state, an agent’s loss function has an additional “beauty contest” component with a fixed weight. defined over the distance between her action and the average action across all agents, this assumed “beauty contest” component of utility not only gives rise to the commonality role of public information, but also fixes the intensity of this commonality role. as a result, when the fixed weight is great and public information is noisy enough, the fixed commonality role dominates the diminishing information role and public information becomes detrimental to social welfare, which is defined as the negative of the average mean-squared error between individual action and the true state. the following exercise gives us a glance at the importance of the endogenous link between the dual role of public information. recall that r measures the intensity of the commonality role and that it is increasing in α. now we fix r to be a constant, r, so that the commonality role is decoupled from the information role. observation . when the keynesian-beauty-contest effect is fixed at r, provisions of public infor- mation decrease market efficiency if and only if r and α are such that α < ( − r)(β + ρ )( − (β + ρ ) ρ ( − r)) ( ) and − ρ (β + ρ ) < r < ( ) in the sense that fixing an endogenous variable to a constant inherently has too many degrees of freedom, observation is more a back-of-the-envelope calculation than a rigorous statement. however, it gives some clues about the importance of the endogenous link between the dual role of public information in determining its market efficiency consequences. when the public information is relatively noisy (condition ) and the keynesian-beauty-contest effect is fixed at a high level (condition ), provisions of public information reduce market efficiency. in this sense, conditions and resemble condition in morris and shin ( ). therefore, the comparison of proposition and observation suggests that the detrimental social welfare effect of public information in morris and shin ( ) may result from the assumed “beauty contest” utility, an observation that warrants further investigation. conclusion i study the market efficiency consequences of accounting disclosure in the context of stock markets as a keynesian beauty contest. in such markets, public information performs both an information role and a commonality role. because the dual role of public information is endogenously linked to each other via the quality of public information, disclosure of public information, however noisy it is, always brings stock prices closer to the fundamental value. transparency should not be compromised on grounds of the keynesian-beauty-contest effect. accounting disclosure is a distinct feature of modern corporations characterized by dispersed ownership. previous research on accounting disclosure has mainly focused on agency problems and differential information among investors. this paper provides one example that dispersed ownership has other important consequences for accounting disclosure that have not received the attention they deserve. it opens up many new opportunities for future research. the keynesian- beauty-contest effect may have substantial implications for the trade-off between public and private channels to disclose corporate information, the relation between information quality and cost of capital, and the relation between earnings and stock prices. another promising direction is to include real effects of accounting disclosure so as to exam- ine the allocational efficiency consequences of accounting disclosure in a keynesian-beauty-contest stock market. since allocational efficiency may diverge from market efficiency, such an extension complements this study and deepens our understanding of the real consequences of accounting disclosure in a keynesian-beauty-contest stock market. appendix proof of proposition . i solve for the model in five steps. step : previous work has shown that for an economy in which investors have cara utility functions and the payoff of the security is normally distributed, an investor i’s demand for the risky security is described by equation . step : the information structure in period . assume p = bz + cθ − ds (a- ) for investor i, she interprets p as an independent signal, p ∗ , with precision ρ. p∗ = c (p − bz) = θ − d c s (a- ) ρ = ( c d ) γ (a- ) correspondingly, her information set is i i = (z, p ∗ , x i). notice that p ∗ is the same for all investors although they have differential private information. her belief about the fundamental value θ is characterized by ei[θ|i i] = αz + ρp∗ + βx i α + ρ + β and v ari[θ|i i] = α + ρ + β the estimate of the variance is independent of the realization of signals and thus the same across investors. step : the information structure in period . assume p = a p + b z + c θ − d s (a- ) given the assumption that both z and p∗ are available to investors in period , investor i in period starts with a prior about θ, αz+ρp∗ α+ρ , with a precision of α + ρ. moreover, she also learns from p . given her knowledge about z and p∗ , the independent signal she can extract from p is p ∗ , with precision ρ . p∗ = c (p − a p − b z) = θ − d c s ρ = ( c d ) γ thus her information set is i i = (p ∗ , z, p ∗ , x i). conditional on i i, she forms her belief of θ as follows: ei[θ|i i] = αz + ρp∗ + βx i + ρ p ∗ α + ρ + β + ρ v ari[θ|i i] = α + ρ + β + ρ again the estimate of the variance is independent of the realization of individual investors’ private signals and thus identical across investors. step : solve for p . according to equation , investor i’s demand conditional on i i is d i = τ (ei[θ|i i] − p ) v ari[θ|i i] = τ [αz + ρp∗ + βx i + ρ p ∗ − (α + ρ + β + ρ )p ] = τ [αz + ρ c (p − bz) + βx i + ρ c (p − a p − b z) − (α + ρ + β + ρ )p ] = τ [(α − b c ρ − b c ρ )z + ( c ρ − a c ρ )p + βx i − (α + ρ + β + ( − c )ρ )p ] (a- ) p is determined by aggregating individual investors’ demands and equating it with the aggregate supply. p = (α − b c ρ − b c ρ )z + ( c ρ − a c ρ )p + βx i − s τ (α + ρ + β + ( − c )ρ ) (a- ) the coefficients array (a , b , c , d ) are determined by comparing coefficients in equation a- with those in equation a- . a = c ρ α + ρ + β + ρ , b = α − b c ρ α + ρ + β + ρ , c = β + ρ α + ρ + β + ρ , d = βτ c (a- ) and ρ = β τ γ (a- ) step : solve for p . investor i who purchases stocks in period does not hold them until the firm is liquidated; instead, she resells them at the price of p . her demand, according to equation , is shaped by her expectation about p , which is different from her expectation about θ. in period , investor i’s belief about p is characterized by ei[p |i i] = c ρ α + ρ + β + ρ p + α − b c ρ α + ρ + β + ρ z + β + ρ α + ρ + β + ρ ei[θ|i i] = c ρ α + ρ + β + ρ p + α − b c ρ α + ρ + β + ρ z + β + ρ α + ρ + β + ρ αz + ρp∗ + βx i α + ρ + β = α + ρ + β + ρ [( + β + ρ α + ρ + β )(α − b c ρ)z + β + ρ α + ρ + β βx i + ( + β + ρ α + ρ + β ) c ρp ] and v ari[p |i i] = ( β + ρ α + ρ + β + ρ ) v ari[θ|i i] + ( β + ρ α + ρ + β + ρ ) β τ γ = (β + ρ ) (α + ρ + β + ρ ) (α + ρ + β)ρ her demand is di. di = τ (ei[p |i i] − p ) v ari[p |i i] = τ [ α+ρ+β+ρ (( + β+ρ α+ρ+β )(α − b c ρ)z + β+ρ α+ρ+β βx i + ( + β+ρ α+ρ+β ) c ρp ) − p ] v ari[p |i i] = τ ρ β + ρ [(α − b c ρ) m z + βx i − ((α − b c ρ) m + β)p ] (a- ) where m = + α+ρ+β β+ρ = β + ρ α + ρ + β + ρ (a- ) p is determined by equating aggregate supply with aggregate demand. p = (α − b c ρ) m z + βθ − β+ρ τ ρ s (α − b c ρ) m + β (a- ) the coefficient array (b, c, d) are determined by comparing coefficients in equations a- and a- . b = α α + ρ + βm , c = ρ + βm α + ρ + βm , d = ρ + βm α + ρ + βm β + ρ ρ βτ (a- ) and ρ = ( ρ β + ρ ) β τ γ (a- ) so p is solved for by plugging equation a- to equation a- . p = α α + ρ + βm z + ρ + βm α + ρ + βm θ − β + ρ ρ ρ + βm α + ρ + βm βτ (a- ) p is determined by inserting equation a- and a- to equation a- . p = α + β + ρ + ρ [αz + (β + ρ + ρ )θ − β + ρ ρ ρ βτ s − (β + ρ ) βτ s ] since the coefficients (b, c, d) and (a , b , c , d ) are unique, the linear rational expectations equilibrium in proposition is unique, too. proof of lemma . lemma is proved by using the traditional solution to a single-period noisy rational expectations equilibrium, such as that in diamond and verrecchia ( ). the procedure is the same as that in the proof of proposition , except that ei[p |i i] and v ari[p |i i] in equation a- are replaced by ei[θ|i i] and v ari[θ|i i]. proof of proposition . proposition is proved by showing that the partial derivative of pe with respect to α is positive. define m ′= ∂m ∂α . thus, m ′ = − β+ρ (α+ β+ρ+ρ ) < . p e = es,z(p − θ) = es,z(bǫz − ds ) = b α + d γ = b α + c ρ = ρ(α + ρ + βm ) αρ + (βm + ρ) ∂p e ∂α = ρ(α + βm + ρ)( + βm ′)(αρ + (ρ + βm ) ) − ρ(α + βm + ρ) (ρ + (ρ + βm )βm ′) (αρ + (ρ + βm ) ) = (α + βm + ρ)ρ (αρ + (ρ + βm ) ) [ β m + βm ρ + αρ + ρ − αβ m m ′] > proof of proposition . proposition is proved by showing that the partial derivate of r with respect to α is positive. r = − b c / b̂ ĉ = β( − m ) + ρ ( − k) β + ρ (a- ) ∂r ∂α = − βm ′ β + ρ > proof of observation . observation is proved by showing that the partial derivative of pe with respective to α, evaluated at r = r = β( −m )+ρ ( −k) β+ρ , is negative under condition and . for notational convenience, define b as follows. b = b̂ ĉ = α β + ρ p e = b α + c ρ = c ( b c ) α + ρ = ( − r + b) b α + ( −r) ρ = αρ( − r + b) b ρ + ( − r) α and ∂p e ∂α |r=r= ρ ( − r + b)α (β + ρ ) (( − r) α + b ρ) [α − ( − r)(β + ρ )( − (β + ρ ) ρ ( − r))] (a- ) since α, β, τ , γ , and γ are positive and finite, both m and k lie between zero and one. as a result, < r < . it could be verified that a- < is equivalent to conditions and . references admati, a.r., , a noisy rational expectations equilibrium for multi-asset securities markets, econometrica , – . allen, f., s. morris, and h.s. shin, , beauty contests 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research , – . untitled kent academic repository full text document (pdf) copyright & reuse content in the kent academic repository is made available for research purposes. unless otherwise stated all content is protected by copyright and in the absence of an open licence (eg creative commons), permissions for further reuse of content should be sought from the publisher, author or other copyright holder. versions of research the version in the kent academic repository may differ from the final published version. users are advised to check http://kar.kent.ac.uk for the status of the paper. users should always cite the published version of record. enquiries for any further enquiries regarding the licence status of this document, please contact: researchsupport@kent.ac.uk if you believe this document infringes copyright then please contact the kar admin team with the take-down information provided at http://kar.kent.ac.uk/contact.html citation for published version parkins, wendy j. ( ) “feeling for beauty”. the senses and society, ( ). pp. - . issn - . doi https://doi.org/ . / x link to record in kar http://kar.kent.ac.uk/ / document version author's accepted manuscript “feeling for beauty”: tactile aesthetics & the childhood of may morris wendy parkins w.j.parkins@kent.ac.uk biographical note: wendy parkins, professor of victorian literature at the university of kent, has published widely on the morris family, including jane morris: the burden of history ( ) and william morris and the art of everyday life ( ). keywords: tactile aesthetics, emotions, embroidery, habitus, arts & crafts movement. abstract: may morris ( - ), renowned craftswoman and daughter of william morris, had an unconventional victorian childhood in a home where all the members of the family were engaged in various forms of aesthetic labour, either as amateurs or professionals, and shared an aesthetic philosophy that blended the artisanal and the experimental from which would develop the arts and crafts movement. this article will examine the fragmentary recollections of her childhood recorded by may morris in the introductions she wrote for the twenty-four volume edition of the collected works of william morris as a rich resource for victorian sensory history because of the emphasis she places on the development of the child’s sensorium, especially in relation to touch as the vital sense that linked family intimacy with creative activity. employing the term “tactile aesthetics,” i show how, in the morris household, the pleasurable sensual apprehension of the objects or materials worked by the hands of the craftsperson was inseparable from the complex feelings of connection with others. in such an environment, a feeling for beauty comprised a vital component of habitus, the embodied knowledges and aptitudes that, according to pierre bourdieu, are acquired from earliest childhood through the practices of everyday life within a specific social setting. mailto:w.j.parkins@kent.ac.uk “feeling for beauty”: tactile aesthetics & the childhood of may morris i have tried to show that executive skill and the desire of and feeling for beauty, realized in a work of definite utility, are the vital and essential elements of this as of all other branches of art, and that no one of these elements can the embroideress neglect or overlook if her work is to have life and meaning. if she pursues her craft with due care, and one might even say with enthusiasm, however, she will not only taste that keen pleasure which every one feels in creative work, however unpretending, but the product will be such as others will be careful to preserve: this in itself being an incentive to good work. in the dedicatory note to her decorative needlework ( ), may morris – a renowned craftswoman for morris & co. and the daughter of william morris – encouraged amateur needlewomen to view their handiwork as meaningful creative labour in terms that emphasized the sensory: a “feeling for beauty” is vital if one is to “taste that keen pleasure” which such work can produce. images of taste and touch may be a conventional idiom for conveying a passionate intensity of experience but may morris’s aesthetic was shaped from childhood by an emphasis on sensory experience. i will focus here on may’s anecdotal accounts of childhood which she incorporated into the introductions she wrote for the collected works of william morris, a monumental undertaking she began in that was published in twenty four volumes between and . these introductions, intended to provide the biographical background for her father’s extraordinary productivity in literature, design and political activism, constitute a form of covert autobiography at times as may recalls significant moments of her own early life and situates them in relation to her father’s career. a striking feature of these childhood recollections is their rendering as vivid sense memories: the sights, sounds, smells, tastes and, above all, feel of the phenomena of daily life that may experienced growing up in the s and s. in this article, then, i will show how a focus on the child’s sensorium, as it responded to the rich sensory environment of a home steeped in the aesthetic labour of both her parents, shaped the adult for whom tactile aesthetics and a “feeling for beauty” remained a guiding principle. as a young woman of (and after studying textile design at the south kensington school of design), may morris took on the management of the embroidery section of morris & co., a position she held until her father’s death in . for the remainder of her life, may morris taught and lectured on embroidery, textiles and pattern design, as well as continuing to exhibit her own work (in textile design and embroidery) internationally. before turning to may’s anecdotes of childhood, however, it is necessary to describe briefly the homes where she grew up, beginning with red house – the home built for the newly-wed morrises at bexleyheath in and where both jenny and may morris were born (in and , respectively). in this first family home, shared creative projects were a part of everyday life for the morris family. may describes the vague impressions she retained of the first few years of her life as “dream-pictures” but uses imagery of contact – even contact that painfully permeates the boundaries of the self – to convey how affect was powerfully transmitted through her earliest memories that “impressed on an unconcerned tiny brain … till in later days … their beauty at last pierce[d] the heart” (vol. i: xiv). red house had a formative influence on everything that followed in the morris family history: the family’s interest in diverse arts and crafts, the development of the family business, and the connections forged there with a wider network of creative people (artists, illustrators, architects, ceramicists, poets, embroiderers) who remained close to the family thereafter. the decoration and furnishing of red house was carried out by william and jane morris and their circle of friends and associates, men and women, providing the impetus for the establishment of morris, marshall, faulkner and company (later, simply morris & co., or – to friends and family – “the firm”), a company that designed, produced and sold everything from stained-glass windows and glassware to furniture, tiles, wallpapers and fabrics in a style that embodied the popularization of aestheticism and the rise of the arts and crafts movement. may morris recalled how many striking objects from these early years had “been unconsciously part of my external life” (vol. ii: xii) as an enduring, material legacy of this early aesthetic experimentation in the morris home. as i have argued elsewhere, the decoration of red house was not simply a statement of aesthetic style but said something about the nature of home life as a space where exuberance and playful experimentation – in art and life – could be encouraged (parkins ). while the marital estrangement of william and jane morris has become the stuff of legend, it is easy to overlook the many ways in which william morris’s design principles were shared by his wife, with both parents comprising a united front for their daughters in their passion for interior design, literature and handicrafts (from embroidery to book-making). as may makes clear, jane morris put into practice a morrisian philosophy of the home as a space of beauty, utility and hospitality where creative labour was always at hand. mother and daughters worked together on beautiful textiles for their own home and for friends, as well as embroidery commissions for morris & co. (sometimes in collaboration with jane’s sister elizabeth burden, who became a professional needlewoman and teacher of embroidery). from may’s earliest memories, then, we see all the members of the family working with fabrics and fibres, colours and designs, across different media in a richly sensory domestic environment. after the family left red house in (due to financial reversals), and moved to live above the new workroom and showroom for morris & co. in red lion square, the domestic space they inhabited may have been less utopian than the idyllic red house but it marked an integration of aesthetics at home and at work that made the home seem a magical space for the young may morris where she could observe stained-glass production, hear the glass-painters at work and mess about with dyes and paints of her own. when the family subsequently moved to hammersmith in , the business premises were no longer shared with the domestic space (although this home would accommodate william morris’s socialist activities, providing a meeting space for the hammersmith socialist league, of which may was an active member as a young adult) but both here and in the country home the morrises leased from the early s, kelmscott manor near lechlade, domestic and creative practices were thoroughly imbricated in daily life. from may morris as well as some of the morrises’ contemporaries, we are given an insight into the sometimes volatile daily life of the morris family in their various homes, where the features of morrisian style (rich textiles, simple furnishings, and restrained ornamentation) combined with unstinting hospitality and provided the background for exuberant games, heated debates and creative productivity to an extraordinary degree. the domestic, then, was always a space of creative collaboration for the morrises where what i will call tactile aesthetics – practices of creative making in which the senses, especially touch, were given a priority – were in evidence. while the term “haptic aesthetics” has been used to describe an approach in which a “felt proximity” as well as “actual physical contact” with the aesthetic object is valued (paterson : ; see also fisher : ), i prefer the term tactile aesthetics, to emphasize the more cutaneous aspect of the sense of touch – relating to the skin as receptive to pressure and texture – and the motor skills of the hand, to think about the many creative practices using paper, fabric or thread in which the morrises engaged. tactile aesthetics were associated with the pleasurable sensual apprehension of the objects or materials worked by the craftsperson and with the feelings of connection with others of like mind and skill arising from collaboration – in which objects were passed from hand to hand, worked on simultaneously or sequentially, or produced in the social settings of the studio or drawing room. eve sedgwick’s account of touch is relevant here, as it emphasizes the relational dimension between toucher and touched that speaks to the processes involved in making the “textured objects” that filled the morrises’ home: even more immediately than other perceptual systems, it seems, the sense of touch makes nonsense out of any dualistic understanding of agency and passivity; to touch is always already to reach out, to fondle, to heft, to tap, or to enfold, and always also to understand other people or natural forces as having effectually done so before oneself, if only in the making of the textured object. (sedgwick : ) in this context, every touched object has been touched before – by the hands of the maker, the co-worker, the giver, the admirer, or the user – and carries with it a tactile history, embedded and embodied, as a result. in this way, tactile aesthetics were also directly related to – and derived from – william morris’s critique of the instrumentality of capitalist production that he articulated from the late s onwards. not only did such a mode of production rely on an alienated and exploited labour force, morris argued, it produced inferior goods that did not even enhance the life of the leisured minority who consumed them (see morris ). insisting on the value of touch and tactility in domestic practices and objects was a form of resistance to the sensory deprivation or impoverishment morris associated with the mass-produced commodity, or what he called “sham art” ( ), intended for domestic decoration. morris’s tactile aesthetics, then, premised on a conscious adaptation to the temporality of the body rather than the machine, acknowledged both the duration needed to make beautiful objects by hand and the “longing to set [our] hand” to objects and materials that could offer sensory gratification in the process of making as well as in the final product ( ). in a not dissimilar vein, pierre bourdieu ( ) described a kind of resistance which he saw as a “dynamic friction” that occurs between art and the everyday. bourdieu speculated that aesthetic practices could become the means by which habitus – our internalized predispositions and aptitudes acquired through the social environment we inhabit, from earliest childhood onwards – was transformed ( : - ). our capacities and habits, that is, could be altered through the processes and skills associated with art (or crafts) because such practices foster a sense of heightened awareness, a self-conscious shaping of intention and agency. allowing that habitus manifests both in the habitual ways in which we engage with the world as well as in our more creative improvisations or adaptations to circumstances, bourdieu’s idea of the “dynamic friction” that results from the contiguity of art and everyday life provides a useful means to understand the importance of tactile aesthetics in the morris family: more than a hobby or even a business, their attention to tactile aesthetics was a way of understanding – and re-shaping – the relation between self and other, between intimacy and resistance, that creative practices associated with touch foregrounded. while the morrises often collaborated on aesthetic projects –william and jane taught themselves traditional embroidery practices together at red house; jane and her daughters worked on embroidery pieces for each of their homes as well as for morris & co. – they also engaged in individual projects while sharing the same space. the illustrator edmund new, for instance, described these parallel creative practices during his stay with the morrises at kelmscott manor in . while new worked on his sketches of the manor in the drawing room, “mr morris was designing some cretonnes and miss [may] morris knitted; mrs m[orris] joined us during the morning and continued embroidering a book cover on which she was engaged” (cox : ). such a model of shared creativity may reflect the social practices associated with the feminine handiwork of leisured gentlewomen (see classen : ) rather than the cultural paradigm of the solitary artist working alone in a studio but it re-frames such practices to blur the boundary between amateur and professional, masculine and feminine, and – equally as important – brings such practices into a new kind of visibility: observing others at work in close proximity (whether family or friends) allowed for the sharing of ideas, the influence of one practice or design on another, or the potential to pass the work from hand to hand for advice, admiration, or collaboration. in may morris’s introductions to her father’s collected works, we also gain glimpses into the shared aesthetic practices within the morris home but these introductions necessarily cover william’s entire career and as such presented may with the problem of describing events before her birth or when she was too young to properly observe or understand them. in the opening paragraph of the introduction to volume i, may addresses this issue and makes explicit the narrative strategy she has chosen to adopt in response to this potential problem. what will follow, she writes, is “the child’s picture of ‘things as they seem’ [which] may help to bring the reality before older eyes” (vol. : x), a position she reiterates at the start of volume viii when she reminds the reader, “i am still telling my story from the child’s point of view” (vol. viii: xxvii). may’s emphasis on her status as a child in the early volumes, however, goes beyond the problem of chronology and instead serves a number of other functions. the narrator-as-child strategy firstly gives a strong sense of immediacy to her recollections, stressing their value as “personal impressions” (vol. i : ix), while also mobilizing the romantic myth of the child’s acuity of perception, the capacity of children to feel deeply and experience a sense of wonder as they encounter phenomena – both natural and social – for the first time. the child’s perspective can thus create an estranging effect for adult readers, an effect that is similar to the sense of cognitive estrangement often associated with the aesthetic, which offers the potential to re-present the everyday in a new or challenging light to unsettle our assumptions. the narrator-as-child strategy also makes an implicit claim for authenticity, as when may excuses the “want of art” in her telling of these recollections to emphasize their raw, unprocessed quality in which memories are offered without regard to sifting the profound from the more trivial (vol. i: ix). at the same time, this narrative strategy justifies the partial perspective offered and thus rather disingenuously allows the narrator to avoid confronting any awkward adult realities of her parents’ lives (such as her father’s unreliable temperament or her mother’s infidelity) and therefore enables may to maintain an often idealized perspective on her father in particular by refusing to re-evaluate her childhood experiences in the light of later wisdom or subsequent revelations. it is in this context, then, that the dominance of sense memories in recalling childhood events and places emerges in may’s account. the child’s sensorium is depicted as acutely responsive to the smell, touch or taste of distinctive locations and the adult may often describes how she is still imaginatively transported by a sensory cue in the present – “the taste of angelica on a cake” or the “smell of a glass-painter’s shop” – to what she calls “memory-pictures” of her past (vol. iii: xxiv, xxv). the past remains a tangible presence to the narrator and even a recollection which begins by recalling a prohibition of touch strongly evokes the tactility of substances and materials through which the relationship between parent and child was enacted in the morris home. describing her father’s work table at horrington house (where the morrises lived from to ), may paints a scene of familial intimacy grounded in a shared love of beautiful objects and creative processes: it was a wonderfully interesting table to explore – with the eye, for of course one never dreamt of disarranging or touching a single paint-brush; there were sticks of chinese ink of a special quality (which i was often allowed to grind when wanted), there was precious ultramarine in a slim cake, there was pale gold in shells, and gold-leaf in books, which we were shown standing in ceremonial attitude of respect and drawing in our breath, lest the fragile glitter should break asunder in the least disturbance of the air. and in passing, let me note one picture i retain of this time: we were shown how the gold was laid, and my father would pass the broad badger-hair brush used for taking up the leaf through his forest of thick curls in the orthodox way, before laying it gently on the leaf of gold. that made us laugh: then the brush, ever so slightly greased by this simple means, took even hold of the leaf and laid it delicately on the cushion where it was dexterously cut. i have seen the same process many times enough since, but never without my thoughts going back to the little house in chiswick – the bare light room, the plain work-table; the splendid head bending over the gold, and the two young heads laid close, and the curly locks all mingling … (vol. ix: xvii, ellipsis in original) here, where even a breath can have a haptic dimension, with its capacity to make contact with – and disperse – the gold-leaf, the fragility of the exotic materials and the need for gentleness of touch underpins the reverence for the creative process shared by the father and his daughters. william morris is linked indexically with his work materials – as he touches his brush to his hair before picking up the leaf – and he becomes the means by which all three morrises present are connected through contact, in the “mingling” of their curly hair as they intently attend to the work at hand. william morris was not, however, always so protective of his materials, often keen to share his new discoveries of craft processes or materials with his daughters, as when he turned his attention to dyeing fibres and fabrics, setting up a dye-shop in the basement of the family home in . “the air at home was saturated with dye-ing,” may morris recalled, bits of madder and indigo lay about, papers of the kermes insect brought home and its habits and customs explained…. even we children were presented with a set of dye-stuffs – how well i remember the look of the broad-stoppered bottles filled with queer powders and lumps and grains that stood in an inviting row on a shelf in the schoolroom, and what distressing messes we made with them! (vol. xi: xvi) while there is no explicit mention of touch in this passage, it again evokes a sense of palpable contact between the child and the craft materials: the “saturated” air suggests the extent to which the morris home was permeated by the aesthetic, while the “distressing messes” made with the dye-stuffs implies a ‘hands-on’ approach typical of child’s play and artistic creativity alike. may morris’s lifelong devotion to her father’s ideals in both art and politics is evident throughout her introductions to his collected works but, perhaps as a result, her relationship to her mother is often overlooked. as an accomplished needlewoman carrying out and supervising commissions for morris & co., as well as making and embellishing decorative objects and items of clothing for personal use or for friends and family, jane morris exemplifies christine bayles kortsch’s contention that textile literacy became a form of feminine cultural capital in this period ( : ). a working-class woman by birth, jane morris had entered a radically different environment on her marriage to william morris: not only did she acquire a new level of social status and affluence but she entered a social network in which creativity was the modus operandi for men and women alike and where she became a full participant in the aesthetic experimentation that characterized the morris circle. within this group, jane morris’s closest female friends were creative women who supported themselves (and sometimes their families) through their work, like the artist marie spartali stillman, the author and embroiderer mary de morgan, and the illustrator olive cockerell. creative women like this looked to historical models of art or craft to express their creativity but not in a kind of anti-modern or retrograde way such as talia schaffer ( ) has recently associated with an arts and crafts aesthetic. schaffer’s account underestimates both william morris’s impact on progressively- minded female craftswomen and interior designers in this period and also the ways in which women like jane morris and her friends negotiated their work and identity in relation to new and emerging theories of art, work and the domestic, as pamela gerrish nunn ( ) has argued. the example of jane morris complicates the historical narrative offered by schaffer, of women’s domestic handicrafts superseded by the masculine cultural authority of designers and practitioners of the arts and crafts movement. jane morris was neither simply a “leisured female producer” (schaffer : ) nor a professional craftswoman to the same degree as her daughter may. the work she carried out, however, exemplified an ethos of aesthetic production that was not defined against modernity but squarely positioned within it: as a socially-mobile woman, she had painstakingly acquired the skills to produce accomplished work – from needlework commissions for morris and co. to ornamented dresses worn to model for the artist dante gabriel rossetti. as such, she had more in common with her daughter may than has often been acknowledged. it is perhaps puzzling, then, that may does not emphasize jane morris’s creative labour in the introductions to her father’s collected works but, in the context of may’s almost synaesthetic evocation of the past, the association she draws between her mother and the tactile is nonetheless a striking one. in the midst of her account of life in queen square, for instance, may interrupts her memories of the firm’s stained- glass commissions and her father’s woodcuts with a single-sentence paragraph: “and in all these pictures comes and goes the figure of my mother, in soft silk gowns that we loved and stroked” (vol. iii: xxv). the pleasure of stroking silk is so strongly bound up with may’s childhood memories of her mother that it is repeated more than once in these introductions. in another volume, may recalled that rossetti’s portrait of jane morris (also known as the blue silk gown) perpetuates a delicious, simple silk gown of shot blue and brown that was a great favourite with the little girls. it had some fragile ornament of gold thread at the throat and wrists, and was of a delicate, faintly-rustling texture, that we never tired of stroking. the merest glance at the indian chain and bracelet in the picture bring back vividly the fragrance of the painted cedar-wood casket where mother’s lovely ornaments were kept. we were allowed to play with it sometimes on sunday afternoons, with reverent adoring fingers that did no damage to the treasures it contained. (vol. ii: xxxv) the sensory elements may describes – the look, feel and sound of the garment, the handling of precious objects, the smell of the wooden casket – underline the inextricable association between such rich sense impressions and her mother. the treasured preservation of the elements that appeared in this portrait – the dress and jewellery – also symbolizes the complex set of emotional identifications and affective connections present in the morris home. rossetti’s painting, the casket decorated by elizabeth siddall (rossetti’s wife, who died tragically in ) where the bracelet designed by rossetti was kept, the dress made and embroidered by jane, each in turn is strongly cathected by may as precious and meaningful. object and creator are indissoluble from the feelings (in both senses of the word) that are recalled through this recollection. the memory, that is, is not simply that of a child’s play at ‘dressing up’ but of beautiful objects highly valued for their connection with beloved people and places, forming the fabric of daily life for a child in the morris household. while the reverence with which may recalls the dress and jewellery suggest these were not ‘everyday’ items, it places them within the parameters of domestic life, connecting mother and daughters with the portrait, the jewellery and the casket in a way that assumes the imbrication of creativity, emotions and senses. another striking aspect in these memories of touching silk, however, is the way the silk both represents and displaces the mother. does this mark an emotional distance between mother and daughter, where the desired contact with the mother is absent but displaced onto the mother’s possession, the dress? or is the silk dress a form of transitional object, which allowed the satisfaction of the desire for intimate contact while also marking the child’s awareness of her separation from the mother, a stage necessary for a child’s development of independence and creativity? in d. w. winnicott’s account, the “transitional object” serves a vital role in a child’s transition from absolute dependence on the mother towards relative independence, through the adoption of a special object to which the child attaches significance and affection. in winnicott’s words: “sooner or later in an infant’s development there comes a tendency on the part of the infant to weave other-than-me objects into the personal pattern” ( : ). the metaphor of weaving aptly picks up on the craft and aesthetic practices associated with the morris household, as does winnicott’s description of the characteristics of the types of objects which may commonly be co- opted by the child in this way: such an object, winnicott conjectures, “must seem to the infant to give warmth, or move, or to have texture, or to do something that seems to show it has vitality or reality of its own” ( : emphasis added). the “faintly- rustling texture” of the silk gown may recalls captures precisely the dimension winnicott emphasizes: “rustling” implies not only sound but movement, a quality also evident in the “shot” silk which seems to change colour from blue to brown only as the garment moves to pick up different aspects of the light. the gown, alive but fragile, draws the touch of the child, an image that embodies a desire for contact with the beautiful in which the mother and the aesthetic become merged. may’s tactile recollections of childhood in fact described a number of transitional objects through which the child enacted and mediated desires for both the mother and the father at the same time as she tested the boundaries of her relationship with her parents and her growing sense of independence from them. on another occasion, she recalled: my best beloved doll was a discarded little jointed lay-figure of father’s, whose name was john. when mother was specially unwell and lay abed, i used to bring him down wrapped in a ragged piece of green baize (he had no wardrobe) to pay her a visit. she had to kiss the dint on his gaunt nose, much to my father’s amusement, and i thought my treasure would surely comfort her. (vol. iv : xiii) may’s doll ritual allowed the child to express her love for her mother while also momentarily reversing the roles of parent and child, carer and patient. the masculine- gendered doll – named “john” and described as belonging to may’s father – also situates the transitional object within a triangular relationship between child, father and mother, where the child effectively orders the mother to love the father (by kissing the father’s doll) while bestowing the ‘gift’ of the father upon the mother. may had previously described other more typical dolls she had possessed as a child so her choice of “john” as a gift was a meaningful one. as a “lay-figure,” an articulated figure used by artists to copy the proportion and posture of the body, john was squarely located within the aesthetic domain of family life, his function and context undisguised because john “had no wardrobe.” even here, however, the tactile is evoked, through the contrast described between john’s only covering, a “ragged piece of green baize,” where the adjective “ragged” connotes the rough feel of the fabric compared to the smoothness of his “gaunt nose.” recalled in a light-hearted tone as part of a narrative sequence may designates “gossip about dolls and things,” the story of john nonetheless represents a powerfully resonant, if largely non-verbal, emotional transaction within the morris family in which touch connects what is loved – parents, dolls – with a broader context of aesthetic production. in her memories of her parents, may’s emphasis on touch renders love a profoundly sensory experience where to love is to touch and to touch is to love. tactile aesthetics, then, were an expression of both art and intimacy for the morrises, articulating family values that were first put into practice in the home and then carried over into the family business, morris & co. the daughter’s lifelong fascination for, and cultivation of, sensory aesthetic experience in the form of embroidery and textile design can be understood as a significant weaving together of family affection with shared practices and objects. within the uniquely creative environment of the morris household, may morris’s upbringing both stimulated her sensory capacity as a child and shaped the re-telling of her memories in strongly sensual terms. when, in decorative needlework, may urged that an embroideress must have a “desire of and feeling for beauty” if “her work is to have life and meaning,” she could well have been articulating her own experience of the vital imbrication of all these elements – life, work, meaning, beauty, desire – in a “personal pattern” (winnicott : ) that began with an awareness of texture and the impression of affect, and touched every aspect of family life from childhood onwards. references: bourdieu, pierre. . “habitus.” in jean hillier and emma rooksby (eds), habitus: a sense of place, pp. - . aldershot: ashgate. classen, constance. . the deepest touch: a cultural history of touch. urbana: university of illinois press. cox, david. . “edmund new’s ‘diary of a visit to kelmscott manor house.’” journal of william morris studies ( ): - . fisher, jennifer. . “relational touch: towards a haptic aesthetics.” parachute ( ): - . kortsch, christine bayles. . dress culture in late victorian women’s fiction: literacy, textiles and activism. farnham: ashgate. morris, may. . decorative needlework. london: joseph hughes & co. morris, may. . introductions to the collected works of william morris. vols. ii, iii, iv, ix, xi. london: longmans, green & co. morris, william. . “the prospects of architecture [ ].” in may morris (ed), the collected works of william morris, vol. xxii, p. - . london: longmans, green & co. morris, william. . “how we live and how we might live [ ].” in may morris (ed), the collected works of william morris, vol. xxiii, p. - . london: longmans, green & co. nunn, pamela gerrish. . “bewitched, bothered and bewildered by the beauty of life.” in wendy parkins (ed), william morris and the art of everyday life, pp. - . newcastle: cambridge scholars publishing. parkins, wendy. . “feeling at home: gender and creative agency at red house.” journal of victorian culture ( ): - . parkins, wendy. . jane morris: the burden of history. edinburgh: edinburgh university press. paterson, mark. . the senses of touch: haptics, affects and technologies. oxford: berg. schaffer, talia. . novel craft: victorian domestic handicraft and nineteenth- century fiction. oxford: oxford university press. sedgwick, eve kosofsky. . touching feeling: affect, pedagogy, performance. durham: duke university press. shaw, george bernard. . “william morris as i knew him.” in may morris (ed), william morris: artist, writer, socialist. vol. . oxford: blackwell. winnicott, d. w. . “transitional objects and transitional phenomena: a study of the first not-me possession.” the international journal of psycho- analysis ( ): - . in addition to exhibiting work regularly at arts and crafts exhibitions in britain, may morris also exhibited at the universal exhibition in ghent in and the exposition d’arts décoratifs in paris in . for an examination of the scandals attached to the morris marriage, see parkins ( : - ). in her teenage years, jenny morris was diagnosed with epilepsy and lived the remainder of her life as an invalid, subject to repeated seizures which were relatively untreatable by victorian medicine. while jenny, who outlived both her parents, continued to read widely, travel, engage in amateur craftwork and take an active interest in her father’s politics, she had no significant involvement in the family business. see, for example, shaw ( ). for accounts by jane morris of these shared projects, see william morris papers, british library, add (on her work with william morris) and the cockerell papers, national art library, victoria & albert museum, msl/ / / (on her work with may). while, on occasion in later volumes, may will acknowledge that she is indebted to her mother’s memory for some information, the introductions also contain many extracts from the correspondence of her father and his friends and colleagues to provide detail and to assure her readers of the accuracy of her account. for instance, a doll she had “named lady audley because of her yellow hair,” after mary elizabeth braddon’s sensational heroine of the same name, may buried in the garden one day, to the distraction of the employees in the morris & co. workshop who observed the uncanny scene (vol. vi: xxxi). games:science:science_magazine_ - :root:data:science_ - :pdf: _v _n :p _ .pdf [ganino] ganino user tools register log in site tools search tools show pagesource old revisions backlinks recent changes media manager sitemap register log in > recent changes media manager sitemap trace: games:science:science_magazine_ - :root:data:science_ - :pdf: _v _n :p _ .pdf this topic does not exist yet you've followed a link to a topic that doesn't exist yet. if permissions allow, you may create it by clicking on create this page. page tools show pagesource old revisions backlinks back to top cognitive e¤ort in the beauty contest game� pablo brañas-garza & teresa garcía-muñoz globe: universidad de granada, spain roberto hernány economic science institute, chapman university, usa september , abstract thispaperanalyzes cognitive e¤ort in di¤erentone-shotp-beauty games. we use both raven and cognitive re�ection tests to identify subjects�abilities. we �nd that the raven test does not provide any insight on beauty contest game playing but crt does: subjects with higher scores on this test are more prone to play dominant strategies. keywords: beauty contest game, raven, cognitive re�ection test introduction recent papers connect individuals�cognitive abilities with performance in di¤erent games through di¤erent tests (see for instance burnham et al., ; oechssler, roider and schmitz, ; brañas�garza, espinosa and rey-biel, ). this paper expands on this literature using both the raven and the cognitive re�ection test (crt hereafter) to study how people play a series of sixp�beautycontestgames. we�ndthat theraventest lacks explanatory power, but the crt makes a di¤erence. an increasing amount of literature analyzes the connection between eco- nomic behavior and cognitive abilities. frederick ( ) shows that subjects who score high on the crt are more patient and more willing to take risks in �special thanks to sej - /econ ycorresponding author: economic science institute, chapman university, roberto.hernangonzalez@gmail.com gains. benjamin, brown and shapiro ( ) show similar results for chilean high school students and, with a more heterogeneous sample, dohmen et al. ( ) also �nd that cognitive abilities are related to time and risk prefer- ences. interestingly, brañas-garza, guillen and lópez ( ) �nd that risk attitudes are similar across subjects with di¤erent computational abilities. oechssler et al. ( ) show that subjects with low scores on a cognitive test are more likely subjected to the conjunction fallacy and to conservatism to update probabilities. analyzing the entries in a travelers�dilemma game, brañas-garza, guillen and lopez ( ) �nd that subjects who score better on a gre-type math test tend to "undercut" the rival. assuming rationality and common knowledge of rationality, the beauty contest game (bcg hereafter) has a unique nash equilibrium, i.e., play zero. however, this equilibrium has not been observed in the laboratory setting for the one-shot game, although players tend to the equilibrium after sev- eral repetitions with feedback. alternatively, the literature has considered equilibrium strategies according to depths of levels of reasoning (cognitive hierarchy of thinking) that better describe behavior in this game (nagel, ; camerer, ho and chong, ). a higher level of reasoning indicates higher strategic behavior by subjects and the belief that rivals are also more strategic. burnham et al. ( ) investigated the relationship between cognitive abilities and choices in a beauty contest game (bcg). they found that in- dividualswithhigher scoresonthecognitive test choosenumbers closer to the nash equilibrium in the one-shot bcg. they point out that this result could be driven by the fact that subjects with lower scores have more mathematical di¢ culties �nding the equilibrium as they choose dominated numbers . but they also argue that this result could be related to di¤erences in predict- ing other participants�choices (out of the equilibrium). coricelli and nagel ( ) show individuals�brain activity is di¤erent when playing a bcg with another human participant than when playing with a computer that selects the numbers randomly. furthermore, they �nd that subjects with a higher level of reasoning expect other participants to play strategically, while low- level reasoning subjects choose in the belief that others will play randomly (see coricelli and nagel, on the theory of mentalizing). according to the theory of mentalizing , bruguier, quartz and bossaerts ( ) �nd that skill in predicting price changes in markets with insider correlates with scores burnham et al. ( ) study a bcg with a parameter of p= / . therefore, numbers higher than are dominated by . �... humans detect malevolence or benevolence by online tracking of changes in their environment (rather than, say, logical deduction about the situation at hand)�(bruguier et al., , p. ). on �eye gaze�and �heider�tests of mentalizing. interestingly, bruguier et al. ( ) do not �nd evidence of correlation between participants ability to predict price changes and their score in a mathematics test . we analyze the raven test and the crt as they have appealing char- acteristics for playing the bcg. raven�s progressive matrices test (raven, raven and court, ) measures visual reasoning and analytic intelligence, the capacity to learn from immediate experience with the problem without rely ing on previous knowledge, and mathematical reasoning (mills, ablard and brody, ; ablard and mills, ). the second test is the crt pro- posed by frederick ( ); a short test with only three brief questions that can be answered in less than minutes. the three items of the crt are designed such that the intuitive response is incorrect, but can be correctly reconsidered through some deliberation. in this sense, the crt measures cognitive re�ectiveness or impulsiveness, respondents�automatic response versus more elaborate and deliberative thought, and is also a good indicator of mathematical skills. experimental methods a total of subjects ( males and females) participated in the experi- ment. the experiment was run over sessions; sessions with participants each and one session with participants. the experiment was programmed and conducted with the software z-tree (fischbacher, ) at the �old� experimental laboratory of the university of granada, spain. the subjects came to the lab and played six rounds of the bcg, one round of the raven test and one round of the crt in that order. subjects were not allowed to use pencils or paper to make calculations. additionally, they completed some questionnaires and performed some risk lotteries (not reported here). . beauty contest game the beauty contest game consisted of guessing an integer number between and (both limits included) in which the winner is the person whose number is closest to m*(average of all chosen numbers). in contrast to burnham et al. ( ), we ran six di¤erent one-shot bcg where m �the known multiplier parameter �takes values: = ; = ; = ; = ; = and = : coricelli and nagel ( ) �nd a similar result. the original instructions are in spanish. the instructions were provided by rosemarie nagel. the subjects were distributed into groups of individuals. the winner of each round received euros. in the event of a tie, the euros were split between those who tied. we did not provide any feedback between trials. information about the results of the game was provided at the payment stage (see below). all the subjects played the di¤erent versions of the game in the same order: m�s by screens screen : m = = screen : m = = screen : m = = screen : m = = screen : m = = screen : m = = observe that we chose this particular ordering of values of m in such a way that: i) participants would �nd it more di¢ cult to learn as the values increase and decrease from one game to the next. ii) furthermore, this design allows us to distinguish between players who play random numbers and those thinking about their best strategy . . raven & crt tests originally developed by dr. john c. raven in , raven�s progressive matrices are multiple choice tests of abstract reasoning. in each test item, a subject is asked to identify the missing item required to complete a larger pattern (see figure ). in our case, subjects face matrices, that is, they make choices. we calculate raveni as the sum of correct answers, hence raveni [ ; ] where indicates that the subject correctly �lled the matrices. we did not organize the subject pool into smaller groups with di¤erent orders to keep the large size of the pool. figure : an example of one test item in the raven�s test the �nal score is a measure of ability for abstract analytic reasoning and �uid intelligence, that is, an ability that does not rely on knowledge or skill acquired from experience as opposed to crystallized intelligence (see horn and catell, ). following burnham et al. ( ), we expected to �nd a negative relation between high scores on the test and entries in the bcg. once the subjects �nished the raven test, they completed the crt de- veloped by frederick ( ). the crt consists of three short questions: . a bat and a ball cost $ . in total. the bat costs $ . more than the ball. how much does the ball cost? . if it takes machines minutes to make widgets, how long would it take machines to make widgets? note that there is a unique nash equilibrium (for any of the bcgs de�ned in this paper) where all players play zero. due to an unintended typographical error, the second question of the crt was shown to the participants as follows: if it takes machines minutes to make widget, how long would it take machines to make widgets?. in this case, the intuitive response is not , as in the original version. since we analyze players�behavior according to the number of correct answers, and not their impulsiveness, this has not a signi�cant impact in our results. note that the correct answer now, minutes, is a little bit more di¢ cult to calculate. we have replicated the analysis using only questions one and three in the crt, and we don�t �nd substantial di¤erences in the results. . in a lake, there is a patch of lily pads. every day, the patch doubles in size. if it takes days for the patch to cover the entire lake, how long would it take for the patch to cover half of the lake? the three questions have an obvious incorrect answer ( , , and ), that can be easily corrected upon minimal re�ection. those who arrive at the correct answers are less impulsive and more likely to engage in re�ective thinking . in this sense, the crt can be viewed as a combination of cognitive capacity and the disposition for judgement and decision making (finucane and guillon, ; toplak, west and stanovich, ). toplak, west and stanovich ( ) put forward that the crt captures important character- istics of rational thinking that are not measured on other intelligence tests. theyargue that humans tendtouse the simplest cognitive mechanism, which could mean that sometime behave not fully rational. the crt is computed as the number of questions answered correctly. frederick ( ) shows that the scores are highly correlated with some other tests of analytic thinking (such as the act, nfc, sat and wpt). we predicted that subjects that do better on this test are more likely to choose lower entries in the bcg. its important to mention here that the subjects completed the crt as the last task. moreover, they did the test in front of a computer and without pencils or paper to make their calculations. this may explain why the results are, on average, not so good ( individuals, % of the sample pool, did not provide any right answers) compared to those shown in frederick ( ) . since we were interested in detecting speci�c subjects who are able to solve these questions �without any help�this particular set-up posed no problems for us. in this sense, our sample of subjects is a lower bound. moreover, our bcg is also computerized, hence this appears to be the most "sensible" comparison. as expected, scoring on the raven test and the crt are correlated (spearman�s rho � = : ;p�value < : ). for example, the third question is particularly interesting in our case as it requires some recursive thinking to be solved. this could be the case for the bcg and the way to think about it in a step-by-step reasoning procedure (see coricelli and nagel, for an extensive discussion) only % ( out of ) and % ( out of ) of the subjects scored and on the crt, respectively. none of the subjects responded correctly to the three questions. frederick ( ) reports that %, %, %, and % of the participants scored , , , and , respectively. results first, we explore the e¤ect of individual cognitive abilities through the bcg. as in previous studies, just a few subjects played according to the nash equilibrium. for all six games, the choices range from to . figure shows the mean values of the subjects�choices, which were classi�ed for their score on the crt (crt= vs. crt> ). it is easy to see that subjects� choices are related to their performance on the crt. figure : average guess by crt table shows a series of six tobit models where the dependent variable is, in each case, the individual guess, gi [ ; ]. as independent variables we used female, raveni and crti. the models are presented in the same order in which they were played. there are two salient results: i) raven is never signi�cant, and ii) crt appears to be signi�cant after two trials. after minimal experience, subjects with a positive score on the crt behave better . the choices ranged from to in the �rst game (m = = ) and in the last two games (m = = , m = = ). it is important to remark here what the raven test captures: subjects�ability to learn from immediate experience. table : estimated e¤ects of cognitive abilities = = = = = = female � : � : � : � : � : � : ( : ) ( : ) ( : ) ( : ) ( : ) ( : ) raven � : � : : � : : : ( : ) ( : ) ( : ) ( : ) ( : ) ( : ) crt : � : � : � : � : � : ( : ) ( : ) ( : ) ( : ) ( : ) ( : ) *(p-value) we study also how subjects play across games. first, we analyze the number of players who played dominated strategies and the relation to the cognitive tests. we observe that the proportion of players that never played a dominated strategy di¤ers according to their crt score: : % of players with crt = versus : % with crt> , although this di¤erence is not signi�cant (p�value = : , proportion unilateral test). wecomputethevariable irrat ( [ ; ])as thenumberof times thesubject played dominated strategies, i.e., if �guess > m� � . we must emphasize that it is not the same to fail in the �rst game (m = = ) than in the last one (m = = ) as the last choice is assumed to be easier. in the last guess, subjects have already learned through the pure experience of the game (feedback free learning; weber, ). the variable exp_irrational captures this idea. we de�ne exp_irrational ( [ ; ]) as the number of times the subject plays dominated strategies weighted by the order they were played . table below shows the results of estimating the e¤ect of both raven and crt on rationality. we use censored tobit regression with normal dis- turbances models according to the values of the dependent variable. note that the use of > instead of � is not trivial. this is because when subjects guess the = m* , they are not best-responding. in any case, there are very few subjects in this extreme case. exp_irrat= � irrat + � irrat + � irrat + � irrat + � irrat + irrat table : learning across tasks irrat. exp. irrat female � : � : ( : ) ( : ) raven : : ( : ) ( : ) crt � : � : ( : ) ( : ) *(p-value) once again we �nd that raven does not have any explanatory power. however, crt appears to be signi�cant again: subjects with positive scores on the crt are less prone to play dominated strategies. this is true for both de�nitions of learning. concluding remarks the bcg is an intriguing game in that only a tiny fraction of people are able to solve it, but once the logic of the game is revealed, most people �nd the nash equilibrium to be an obvious prediction. this paper explores if people who are able to solve the bcg have higher cognitive abilities. we measure intelligence using two complementary tests: the raven and the crt. our subject pool played six (incentivized) one-shot p-beauty games without any feedback. we �nd that subjects with higher scores on the crt test are more prone to play according to the nash equilibrium. in sharp contrast, the raven test does not provide any insight on bcg playing. references [ ] ablard, k. e. and c. mills, . evaluating abridged versions of the ravens advanced progressive matrices for identifying students with academic talent. journal of psychoeducational assessment ( ): - [ ] benjamin, d. j., s. a. brown and j. m. shapiro, . who is "behav- ioral"? cognitive ability and anomalous preferences. levine�s working paper archive , david k. levine. 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[pdf] borrowed beauty? understanding identity in asian facial cosmetic surgery | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /s - - - corpus id: borrowed beauty? understanding identity in asian facial cosmetic surgery @article{aquino borrowedbu, title={borrowed beauty? understanding identity in asian facial cosmetic surgery}, author={yves saint james aquino and norbert l steinkamp}, journal={medicine, health care and philosophy}, year={ }, volume={ }, pages={ - } } yves saint james aquino, norbert l steinkamp published sociology, medicine medicine, health care and philosophy this review aims to identify ( ) sources of knowledge and ( ) important themes of the ethical debate related to surgical alteration of facial features in east asians. this article integrates narrative and systematic review methods. in march , we searched databases including pubmed, philosopher’s index, web of science, sociological abstracts, and communication abstracts using key terms “cosmetic surgery,” “ethnic*,” “ethics,” “asia*,” and “western*.” the study included all types of papers… expand view on springer philpapers.org save to library create alert cite launch research feed share this paper citationsbackground citations view all figures, tables, and topics from this paper figure table figure table table figure view all figures & tables sense of identity (observable entity) cosmetics rhinoplasty scientific publication paper societies abstract summary citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency cosmetic surgery consideration among male and female university students in five asean countries s. pengpid, k. peltzer, niruwan turnbull medicine save alert research feed the south asian facial anthropometric profile: a systematic review. maria raveendran medicine journal of cranio-maxillo-facial surgery : official publication of the european association for cranio-maxillo-facial surgery save alert research feed surgeon, media, society, patient: four factors in determining the ethics of cosmetic surgery brett lunceford medicine save alert research feed discrepancies in east asians' perceived actual and ideal phenotypic facial features michael thai, anthony j. lee, jordan r axt, m. hornsey, f. barlow psychology pdf view excerpts, cites background save alert research feed cosmetic patient evaluation t. zhu, ali banki, mohammad banki medicine save alert research feed a novel method to enhance dynamic rhinoplasty outcomes: double “v” carving for alloplastic grafts shanshan bai, dong li, l. xu, huichuan duan, j. yuan, m. wei medicine ear, nose, & throat journal view excerpt, cites background save alert research feed beauty or the beast? university academics’ perceptions of women’s physical appearance and academic achievements ladan rahbari psychology view excerpt, cites background save alert research feed understanding and treating different patient archetypes in aesthetic medicine s. liew, michael b silberberg, jonquille chantrey psychology, medicine journal of cosmetic dermatology save alert research feed consumer reactions to female and male cosmetic surgery beauty in asian advertisements p. tipgomut, l. paas, angela mcnaught psychology save alert research feed workflow and strategies for recruitment and retention in longitudinal d craniofacial imaging study r. denadai, junior chun-yu tu, + authors pang-yun chou psychology, medicine international journal of environmental research and public health pdf view excerpts, cites background save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency facial aesthetic preferences among asian women: are all oriental asians the same? m. dobke, c. chung, k. takabe medicine aesthetic plastic surgery highly influential view excerpts, references background save alert research feed ethnic trends in facial plastic surgery. angela k. sturm-o’brien, annette e. a. brissett, a. brissett medicine facial plastic surgery : fps highly influential view excerpts, references background save alert research feed aesthetic surgery in asians joseph k. wong medicine current opinion in otolaryngology & head and neck surgery highly influential view excerpts, references background and methods save alert research feed transforming "racial characteristics": is it an appropriate role for aesthetic surgery? n. jablonski medicine aesthetic surgery journal view excerpts, references background save alert research feed cosmetic surgery, racial identity, and aesthetics s. munzer psychology highly influential pdf view excerpts, references background save alert research feed gender, globalization and aesthetic surgery in south korea r. holliday, j. elfving-hwang sociology save alert research feed steven polgar prize essay ( ). medicalization of racial features: asian american women and cosmetic surgery eugenia kaw sociology highly influential view excerpts, references background save alert research feed a contemporary assessment of facial aesthetic preferences. j. biller, d. kim medicine archives of facial plastic surgery pdf save alert research feed korean cosmetic surgery and digital publicity: beauty by korean design g. davies, g. han sociology save alert research feed aching for the altered body: beauty economy and chinese women's consumption of cosmetic surgery w. luo sociology highly influential view excerpts, references background save alert research feed ... ... related papers abstract figures, tables, and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue smith, s. m., mcintosh, w. d., & bazzini, d. g. ( ). are the beautiful good in hollywood? an investigation of the beauty and goodness stereotype on film. basic and applied social psychology, ( ): - . (mar ) published by taylor & francis (issn: - ). are the beautiful good in hollywood? an investigation of the beauty-and-goodness stereotype on film stephen m. smith, william d. mcintosh, doris g. bazzini abstract physically attractive individuals are often viewed more favorably than unattractive people on dimensions that are weakly related or unrelated to physical looks, such as intelligence, sociability, and morality. our study investigated the role of u.s. films in this "beauty-and- goodness" stereotype. in study , we established that attractive characters were portrayed more favorably than unattractive characters on multiple dimensions (e.g., intelligence, friendliness) across a random sample from decades of top-grossing films. the link between beauty and positive characteristics was stable across time periods, character sex, and characters' centrality to the plot. study established that exposure to highly stereotyped films can elicit stronger beauty-and-goodness stereotyping. participants watching a highly biased film subsequently showed greater favoritism toward an attractive graduate school candidate (compared with ratings of an unattractive candidate) than participants viewing a less biased film. the quality of these films is completely beside the point, as they are only required to loyally express my personal worldview—punish the wicked, reward the attractive, and have as little to do with reality as possible. —libby gelman-waxner ( ; italics added) looks may not be everything, but physical good looks usually work in one's favor. such is the conclusion of a quarter century's worth of research on physical attractiveness (pa) effects. do the mass media encourage or reinforce the pervasive stereotypes that link beauty and positive traits? much of the work on the beauty-and-goodness stereotype was triggered by the report of k. k. dion, berscheid, and walster ( ), who found that "what is beautiful is good" in the eyes of many observers. in a variety of studies conducted since that time, physical good looks have been found to elicit many favorable reactions. perhaps not surprisingly, people view physically attractive individuals as more desirable romantic partners (suman & kureshi, ). in addition, good-looking people are judged less likely to commit criminal acts (saladin, saper, & breen, ), attractive defendants are more likely to receive lenient verdicts in mock trials (castellow, wuensch, & moore, ), attractive infants are rated more favorably than less attractive ones (karraker & stern, ), good-looking children are judged to be more socially and academically capable tban less physically appealing ones (kenealy, frude, & shaw, ), grade school children prefer attractive teachers to unattractive teachers (hunsberger & cavanagb, ), and perhaps more alarming, mock jurors recommend harsher punishments for defendants who have raped an attractive woman than those who raped an unattractive woman (kanekar & nazareth, ). the bias toward the physically attractive can also help explain why researchers have found in several studies that good-looking people tend to earn higher incomes than unattractive peers (frieze, olson, & russell, ; roszell, kennedy, & grabb, ; umberson & hughes, ). although some real differences (beyond looks themselves) exist between physically attractive and physically less attractive individuals, these actual differences are few and relatively weak compared to the strength of people's stereotypical beliefs. a meta-analysis of studies of actual correlates of attractiveness by feingold ( ) indicated "no notable relationships between physical attractiveness and basic personality traits" (p. ) or between attractiveness and character (e.g., manipulativeness). the main characteristics that truly separate attractive and unattractive people were found to be loneliness, social anxiety, popularity witb the opposite sex, and variety of sexual experiences. the evidence suggests quite clearly that the preferential judgments and attributions bestowed on physically attractive individuals are out of concert with actual differences in ability, character, and personality relative to unattractive people. nevertheless, a meta-analytic review ofthe pa stereotyping literature showed that even though the magnitude of beauty-and-goodness effects varied considerably among studies, overall researchers found a moderate effect present (eagly, ashmore, makhijani, & longo, ). the effects of attractiveness were strong for judgments of social competence; moderate for judgments of mental health, social dominance, and intellectual ability; and not significant for judgments of integrity and concem for others. even though conceptions of what constitutes pa may be partially determined at birth (langlois et al., ), the beauty-and-goodness stereotype itself is believed to be at least partly learned. but from where is it learned? one possibility is that the stereotype results from direct observation of attractive and unattractive people, in which different characteristics are perceived to covary with attractiveness. however, feingold's ( ) review renders this explanation implausible; attractive people's actual qualities are not much different than those of less attractive people. another possibility is that the stereotype develops through acculturation. important for our research, the entertainment media has been implicated as a source of the stereotype, primarily by portraying physically attractive characters as "good" and unattractive characters as "bad" (e.g., aronson, wilson, & akert, ). but what is the evidence that the popular media portray an unbalanced view of physically attractive people? as noted by eagly et al. ( ), "appropriate content analyses of media content are lacking" (p. ), and hence reviewers of this literature have been forced to fall back on citing a few specific films (most typically, cinderella) to support the contention that the media play a central role in encouraging the beauty-and-goodness stereotype (e.g., feldman, ). our purpose here was to gather evidence bearing on the issue of entertainment media influences on the beauty-andgoodness stereotype. specifically, we sought to analyze a sample of media from the past decades and assess the extent to which beauty is associated with "goodness" (and positive traits in general). we opted to use the film medium for this study. researchers have estimated that almost two thirds of the adult population sees at least two movies each year and, as recently as , u.s. cinemas drew well in excess of billion customers, for an average of approximately five films viewed per u.s. citizen (monush, ). we selected a sample of films from through , and a team of raters evaluated the pa ofthe main characters and a variety of other attributes (i.e., their goodness, intelligence, friendliness, aggressiveness, romantic activity, socioeconomic status [ses], and outcome). in study , we moved to the laboratory and asked participants to view films that we selected based on their level of beauty-and-goodness stereotyping. we then subjected our participants to a task in which they evaluated an application submitted by either an attractive or an unattractive candidate, anticipating greater bias toward the attractive candidate among participants exposed to a highly stereotyped film. study hypotheses our primary hypothesis in study was that characters' pa would be significandy associated with some of the positive characteristics assessed. based on previous findings (ashmore & longo, ; eagly et al., ; feingold, ), we anticipated that the relationship would be strongest between attractiveness and measures of social competence, particularly romantic activity, but also for friendliness, and weaker between pa and intelligence or ses, which are found to be moderately associated with looks (e.g., jackson, hunter, & hodge, ; umberson & hughes, ); and we expected no pa effects on characters' outcome at film's end (e.g., "lived happily ever after"), goodness, or aggression because morality is generally uncorrelated with pa in the literature (e.g., eagly et al., ). we also sought to examine trends over time in the link between pa and positive characteristics. because the beauty bias has been established in the literature since the early s, has public awareness ofthe stereotype led filmmakers to combat it in their films, or has the bias remained stable over time? we predicted that pa effects would be stronger for female characters than for male characters, and we based this prediction on research suggesting that looks are seen as more important to women's gender roles rather than to men's (e.g., bar-tal & saxe, ) and a study of televi- sion ads that found that looks and positive outcomes were more commonly linked for women than for men (downs & harrison, ). research on attractiveness and liking has shown that looks are more important to a woman's ability to attract men than to a man's ability to attract women (e.g., feingold, ; kenrick, sadalla, groth, & trost, ), so we predicted that the difference between pa effects for women and men would be most evident on the measure of romantic activity. finally, we expected that central characters would be portrayed more favorably than peripheral characters. feingold ( ) suggests that leading actors are "not only inordinately attractive, but they also ooze charm and sensuality" (p. ). because the central characters are more noticeable, any covariations between pa and goodness among such characters could be particularly influential. thus we also examined the relationship between pa and goodness across levels of character centrality (central, secondary, and peripheral). method in study we attempted to assess the validity of the claim that hollywood films project a stereotype that favors the physically attractive. to assess this contention, we first needed to identify a representative collection of films. a comprehensive study of all films would have proved too lengthy, so we decided to study a sample of u.s. films beginning with (relatively few films were produced prior to the s). selection of target films to compile a representative pool of films, we started from the assumption that more popular films (i.e., those that drew the largest audiences) would have a greater influence on the prevalence of people's stereotype and hence were more important to examine than lesser known films. thus, we obtained lists of the top-grossing movies from each year between and , counting only a film's revenues at first release. we included the top films from each year in our initial pool; thus we had , films in the initial pool, for each decade.[ ] to arrive at a more manageable number, we randomly chose films from this initial pool. we imposed one constraint on randomness in selecting these films: we required films for each decade. the resulting sample of films is listed in the appendix and included the following genres: % comedy; % drama; % action-adventure; % musical; % suspense; % children-family; % western; and % science fiction-fantasy. rating procedure we provided extensive training materials for each of the raters ( men, women), and at least people rated each film. films were viewed by an average of . raters, who were instructed to rate all characters identified by name or appear in what the rater considered to be a significant number of scenes. characters were rated on the following dimensions. . attractiveness. we based ratings of pa on an -point scale ranging from (extremely unattractive) to (extremely attractive) and instructed peuticipants to make this rating the first time the character was shown on screen in a reasonably clear, full-faced shot. . aggressiveness. we defined aggressiveness as physical or verbal abuse of other people, and rated it on a scale ranging from (not at all aggressive) to (extremely aggressive). . friendliness. raters assessed each character's friendliness on a scale ranging from (extremely unfriendly) to (extremely friendly). a. goodness. raters assessed the character's moral virtue on a scale ranging from (extremely immoral) to (extremely moral, saintly). . intelligence. raters assessed the character's intelligence on a scale ranging from (extremely unintelligent, a moron) to (extremely intelligent, a genius). . outcome. at film's end, participants rated each character's outcome on a scale of (extremely negative; e.g., death) to (extremely positive; e.g., struck it rich and lived happily ever after.) . romantic activity. participants rated a character's real or implied romantic involvement, sexual involvement, or both on a scale ranging from (totally inactive) to (extremely active). due to changing norms and laws, recent films portray this more explicitly. in an attempt to balance this inequity, raters attempted to estimate how much romantic or sexual activity a character was portrayed to be involved in, rather than consider only the amount of time the characters actually engaged in romantic activity, sexual activity, or both. . ses. participants rated ses on a scale ranging from (extremely poor, lower class) to (extremely rich, upper class). in addition to these ratings, each rater identified the character's sex and rated the character's role in the film as either central (leading character), secondary (supporting character), or peripheral (appearing in only a few scenes). with the exception of attractiveness ratings, raters could make the ratings at any point during the film. however, in cases where a character's aggressiveness, ses, and so forth, changed during the course of the film, participants often revised ratings for that character on that dimension, and we used the last rating in the analysis. raters were required to stick with their original attractiveness rating to eliminate the possibility of altering attractiveness ratings after finding out whether a character was good or bad (e.g., a rater might deduct a few attractiveness points after seeing a character engage in evil acts). whenever two or more raters viewed a film together, we asked that no discussion of the characters or plot of the film occur until all ratings were complete, thereby eliminating opportunities for raters to influence each others' judgments. rater reliability. although we involved several individuals in rating the films, a few raters viewed a disproportionately high number of films. we first sought to establish the reliability of the three raters who were responsible for the majority of the ratings. we assessed their reliability by randomly selecting films from our sample that all three core raters scored. for each of the characters in these films, we analyzed the reliability of these raters for each primary measure using a random effects model. the analysis yielded the following alphas: attractiveness, . ; aggressiveness, . ; friendliness, . ; goodness, , ; intelligence, . ; outcome, . ; romantic activity, . ; and ses, . . we also assessed reliability for a random sample of raters, including both the core raters and the remaining raters. we used character ratings in this analysis in which we again selected films at random and then selected three raters randomly from among those viewing each of these films. again, reliabilities across raters were well above acceptable levels across all dimensions rated, ranging from a low of . (for intelligence) to a high of . (for outcome). the reliability for attractiveness ratings was in the middle of this range (a = . ). from these data, our raters' efforts did not seem to suffer from significant idiosyncratic biases. however, shared biases regarding the covariance between beauty and goodness might have influenced the observed correlations between beauty and the other measured variables. specifically, the raters may have shared a belief that more attractive people are better people and biased their ratings to produce this relationship (e.g., increasing the ratings of attractiveness for characters portrayed positively). to investigate this possibility, we asked a sample of undergraduate volunteers (a^= ) to rate the attractiveness (on the same -point scale we used earlier) of photos of characters taken from our sample of films. we then averaged and compared these ratings to the ratings of attractiveness our raters assigned. for the subsample of characters, the correlation between the ratings generated by the raters and the ratings provided by the students was r = . , p< . . this correlation was undermined by the fact that our undergraduates were surprisingly prone to giving same-sex characters attractiveness scores of , whereas the raters in our study seldom gave ratings of (our guess is that many of the undergraduates believed anything other than a rating of a same-sex person's attractiveness indicated homosexual inclinations). eliminating the zeroes from the student sample elevated the correlation between ratings to r = . . most important, however, the correlation between beauty and goodness was . using our ratings of attractiveness and goodness, and , using the students' ratings of attractiveness and our ratings of goodness. so, if our ratings were biased at all, they appear to be biased against the beauty-and-goodness stereotype, f( ) = . , p < . . we implemented another protective measure prior to the beginning of data collection. each of our core raters submitted a written summary of their expectations of what significant results would be found before viewing any of the films in the study. content analysis of these lists (available from stephen smith) indicated only one consistent expectancy across raters: they expected the relation between beauty and goodness to be strongest in early decades and weakest in the s. as we discuss later, our results suggested nonsignificant variations across decades. taken together, the fact that interrater reliabilities were quite high, that the attractiveness ratings produced by a naive sample of students yielded nominally higher correlations with goodness than our own ratings, and that raters' expectancies of what we would find were completely idiosyncratic (save for one shared expectancy that clearly did not produce the expected finding), argue quite consistently for the reliability of our results. results and discussion test for general pa bias table presents means and standard deviations for all measured variables, and table shows intercorrelations for all measured variables. because the characters appeared with other characters who were also being rated, analyzing all rated characters would violate the assumption of independence. hence, we randomly selected one character from each film for inclusion in the regression analyses. we performed separate regressions using aggressiveness, friendliness, goodness, intelligence, outcome, romantic activity, and ses as criterion variables. predictor variables in these equations included beauty, character sex (coded = female, = male), character centrality (coded = central, - secondary, = peripheral), and decade of film ( = s, = s, etc.). we also entered cross-product interaction terms for beauty x sex, beauty x character centrality, and beauty x decade. we used simultaneous solutions due to the high number of tests conducted. the results of these regression analyses appear in table .[ ] we anticipated that beauty would be most reliably associated with heightened levels of romantic activity and friendliness. although beauty was indeed strongly related to levels of romantic activity, b = . , p < . , it was not a significant predictor of friendliness, b = . , ns. we predicted a moderate level of association between beauty and both intelligence and ses and no association between beauty and either outcome, goodness, or aggression. however, beauty was only weakly associated with intelligence ( = . ,/ < . ) and essentially unrelated to ses (b - . , p > . ). beauty was a weak, unreliable predictor of aggression, b - -. , p < . , with more attractive characters displaying slightly lower levels of aggression. however, beauty was more reliably related to both goodness {b = . , p < . ) and outcome (s - . , p < . ). despite previous research indicating no clear evidence that attractive people actually have better life outcomes (i.e., "living happily ever after"; feingold, ) than unattractive people, this was certainly the case in many of our films. to summarize, our guesses were less than perfect regarding which characteristics would be most strongly related to characters' pa, but we found a clear tendency for attractive characters to be portrayed more favorably overall. variation by decade. to test for variability of pa effects across decades, we examined the beauty x decade predictor terms for each analysis. as noted earlier, several raters expected to find reduced stereotyping in recent films relative to older films, but this was clearly not the case. the interaction between beauty and decade fell far short of significance {ps > . ) for everything except intelligence, for which a significant beauty x decade interaction emerged, b = . , p < . . the positive regression coefficient indicated that beauty was actually a better predictor of intelligence in more recent movies than in earlier ones (see table ). although not particularly germane to our hypotheses, we found a main effect of decade on ratings of intelligence, b = -. , p< . . this result suggested that characters tended to be portrayed as less intelligent in more recent films than in older movies. variation by character sex. we expected beauty to predict more reliably positive qualities in female rather than in male characters. contrary to our hypotheses, large sex differences in the strength of the pa bias did not emerge. the beauty x sex interaction term approached significance only for aggression, b = . , p < . . as seen in table , pa was a modest, positive correlate of aggressive behavior for male characters, although beciring a slight, negative relationship to aggression in female characters. variation by character importance. we performed a final set of analyses to test the hypothesis that central characters would be portrayed more favorably than less important characters. central characters in our sample were indeed rated as more attractive (a/= . ) than secondary (m= . ) characters, t{ ) = . , p < . , or peripheral {m = . ) characters, t{ ) - . , p < . . the latter two groups of characters did not differ in pa, t{ ) = . , ns. regression analyses indicated that central characters also received more favorable ratings than less important characters on friendliness, b = -. , p < . , but no other significant effects emerged for character importance. we also looked at the beauty x centrality interaction terms in the regression analyses to see if the beauty-and-goodness relation varied by character importance. surprisingly, the relation between the beauty x cen- trality interaction and several variables (friendliness, goodness, intelligence, and outcome) was significant (bs = -. , -. , -. , and -. , respectively; all ps < . ). the pattern of these interactions (see table ) suggested that beauty-and-goodness stereotyping was most pronounced for central characters with the primary exception being for outcome, for which we found no relation between beauty and goodness for central characters. this is perhaps due to the fact that central characters seldom die in the film whereas less important characters are more expendable. conclusions the results of our investigation indicate quite clearly that hollywood filmmakers have been portraying physically attractive individuals more favorably than their less attractive film counterparts in terms of their moral goodness, romantic activity, and life outcomes. this bias was reliably present throughout the period studied ( - ), was apparent for both male and female characters, and was most pronounced for central characters. left unanswered in our data, however, is another important question. although the movies may indeed project a stereotyped view of good-looking people, is the public influenced by these stereotyped portrayals? to be sure, much evidence suggests that the messages of the mass media are widely accepted in the population. for example, research has indicated that televised aggression increases many viewers' own aggressiveness (e.g., bandura, ross, & ross, ; berkowitz & geen, ). the entire advertising industry is founded on the assumption that public attitudes can be altered by exposure to media messages, and research suggests that repeated exposure to ads does indeed alter attitudes (e.g., schumann, petty, & clemons, ). mass media appeals can increase prosocial behavior as well. for example, when townhouse and apartment dwellers were shown videotaped messages about energy-saving behaviors, they significantly altered their energy-related habits (winett et al., ). most directly relevant to our work, studies have shown that media portrayals of gender stereotypes directly impact the stereotypes of viewers (e.g., geis, brown, jennings, & porter, ). nevertheless, evidence regarding the ability of the media to affect or create stereotypes is scant. the mere presence of stereotypical portrayals in the media tells us little about their influence. for example, studies suggest that changes in stereotypical depictions of black people on prime-time television have coincided with apparent changes in society's views of black people (weigel, kim, & frost, ). but does this suggest that changes in media portrayals have produced changes in public attitudes? does it suggest that changes in public attitudes have produced changes in the programming choices of television executives? or does it suggest that other variables are responsible for both changes? in the absence of controlled studies, we cannot confidently draw causal conclusions. conducting such a study was the objective of our second investigation. study our second study experimentally examined the hypothesis that exposure to films with stereotypical depictions of attractive people as good can subsequently influence the stereotypes of viewers regarding the relationship between beauty and goodness. we selected four films from study for inclusion in our laboratory follow-up. method participants and design. fifty-seven female and male undergraduate students in lower division psychology classes participated for extra credit, and we randomly assigned them to film conditions. approximately one half watched a film that data from study indicated to be high in beauty-and-goodness stereotyping (specifically, correlations between the pa and the goodness ofthe film's characters exceeded . ); remaining participants viewed a film with low levels of beauty stereotyping (with correlations between pa and goodness of less than . ). subsequent to viewing the full-length film, participants completed an "unrelated" second experiment in which they rated the applications of two fictitious graduate school candidates, one of whom was physically attractive and one of whom was physically unattractive (photos were attached to the applications). the photos had been shown to reliably elicit divergent attractiveness ratings in a previous investigation (petty & cacioppo, ). both applicants were of the same sex with target sex manipulated randomly between participants. the resulting design was a mixed factorial including the following variables: film type (high- vs. low-beauty stereotyping; between-participants), participant sex (male vs. female; between-participants), target sex (male vs. female; between-participants), and target attractiveness (attractive vs. unattractive; within-participant). procedures. we informed participants that they were taking part in two separate experiments; the first involved pilot testing a movie for use in future research and the second involved checking the reliability of graduate school admissions decisions. after obtaining informed consent, the experimenter proceeded to show participants one of four films. the films, selected from our initial pool of on the basis of very high or very low beauty-and-goodness correlations according to our ratings, were pride ofthe yankees (high bias, drama). road to utopia (high bias, musical). up the down staircase (low bias, drama), and rhapsody in blue (low bias, musical).[ ] after viewing the film, participants provided several ratings that supported the cover story but were otherwise inconsequential for our study. we then asked them to close the folder containing the film ratings and gave them a second folder containing four sheets. we told them that a nearby university had asked for some assistance in checking the reliability of their graduate school admissions decisions and wanted to have a set of applications rated by novices with no knowledge of the candidates and no special expertise in the planned area of study (psychology). the folders contained two single-page resumes with a black-and-white photograph of the applicant in the upper right corner. the qualifications ofthe candidates were essentially equivalent, but were cosmetically varied to reduce suspicion (e.g., different fonts, college affiliations, and club memberships). each participant judged two applications that were matched on sex and approximate qualifications but whose photographs were manipulated such that one was particularly attractive and the second was particularly unattractive (the main deviation from standardization of the applications was that the unattractive candidate was always identified as having a slightly higher grade point average than the attractive applicant). the attractiveness manipulation was validated in previous research (haugtvedt, petty, & cacioppo, ). we asked participants to take their time reviewing the resumes and then rate the applicants separately on a -point scale ranging from (not at all qualified) to (extremely well qualified). after completing the evaluations, we probed participants for suspicion, debriefed them, and thanked them for their participation. results the primary objective of the study was to see if exposure to beauty-biased films would increase the extent to which people favored attractive candidates. thus the key prediction was an interaction between film type (high vs. low bias) and candidate's attractiveness. the dependent variable was the rating assigned to each candidate on a -point scale. overall ratings of candidates differing in attractiveness. we performed a mixed (film type; between- participants) x (participant sex) x (target sex) x (candidate's attractiveness; within-participant) analysis of variance on the ratings of candidate's qualifications for graduate school. five participants failed to complete this item and were dropped from the analysis. the analysis revealed a significant main effect of pa, f(l, ) = . , p < . , that mirrored past findings. physically attractive candidates received more favorable ratings (m = . ) than did unattractive candidates (m = . ). however, this effect was qualified by a significant interaction, f( , ) = . , /; < . . (see table for means.) simple effects tests indicated that the favoritism for the more attractive candidate was particularly strong among partici- pants exposed to a highly stereotyped film, r( ) = . , p < . , although those exposed to a low-bias film also favored the attractive candidate, r( ) = . , p < . . thus, our study results repeated past findings in that our participants rated attractive people more favorably than unattractive people. importantly, however, we went beyond the past literature by directly demonstrating the influence of a situational variable—exposure to stereotyped films—on the magnitude of the tendency to favor the physically attractive. this effect was the consequence of exposure to only one film. general discussion the pa literature has clearly demonstrated that a prevalent judgmental bias favoring physically attractive people exists; they are viewed as more sociable, more intelligent, better adjusted, and more desirable as romantic partners. indeed, hatfield and sprecher ( ) concluded that physically attractive people are believed to "possess almost all the virtues known to humankind" (p. xix). although the origins of this bias are not clear, most scholars have either directly or indirectly accused the entertainment media of encouraging or maintaining the "what-is-beautiful-is-good" stereotype (e.g., aronson et al., ). however, this criticism has lacked any scientific support beyond the mere citation of a few examples of films that seem to project the beauty-and-goodness stereotype. we could cite no systematic study of a representative sample of films because none existed. in addition, even if a systematic study had existed, no direct evidence could be cited to support the claim that exposure to attractiveness stereotyped films can lead to actual changes in behavior on the part of viewers. these data ameliorate both of these problems in the literature. we found, in a representative sample of films across decades, that pa was significantly associated with goodness, romantic activity, and life outcomes. furthermore, we found that these relationships were consistent across decades. we also discovered that the tendency for physically attractive characters to be portrayed more positively was stronger for central (leading) characters than for lesser characters and that the extent of beauty stereotyping was essentially the same for male characters as for female characters. a second study supported the validity of a causal path from viewing pa biased films to strengthened stereotypes in favor of attractive people. participants who viewed highly biased films were more prone to favor a physically attractive applicant in a bogus admissions decision task. beyond tying up important loose ends in the pa literature, our research testifies to the power of mass media in influencing human attitudes and judgments. when commentators express concern over negative effects of the mass media, they are generally referring to the infiuence of long-term exposure on attitudes and behavior (e.g., myers, ). our data suggest that such concern is indeed warranted with respect to media promotion ofthe beauty-and-goodness stereotype; we were able to document strong evidence that films tend to portray good-looking characters as good and found evidence of increased beauty stereotyping effects based on a single exposure to a beauty stereotyped film. given this finding, expecting that repeated exposure would have more powerful—and for some, deleterious—effects seems plausible (e.g., gerbner, gross, morgan, & signorielli, ). on a more optimistic note, evidence suggests that media infiuences on stereotypes can work both ways. researchers have found that portraying women in positions of authority over men reverses the tendency for men to be viewed as more competent than women (geis, deitz, brofee, & fennimore, ). however, optimism regarding the chances that filmmakers will try and "undo the damage" assumes that these manufacturers of popular media believe they are at least partially responsible for public beliefs and stereotypes. this assumption may not be particularly valid. consider the following quote from director stanley kubrick ( , as reported in karney, ): " . . . the idea that people can be corrupted by a film is, i think, completely wrong" (p. ). our research studied pa in a global sense, but recent work indicates that beauty is multidimensional and that significant differences exist among the different dimensions. for example, ashmore, solomon, and longo ( ) delineated trendiness, cuteness, and sexiness as separate factors sharing a relationship with ratings of pa. quite possibly, these separate factors of pa could be differentially responsible for the beauty bias evident in the films we studied, but we can ascertain this only through further research. determining what the s look like in terms ofthe portrayal of physically attractive characters would also be informative. perhaps we have made progress toward reversing the unfavorable trend apparent in the years of film we sampled. but as was the case for films in general prior to our investigation, our own impressions are all we have to go on to gauge the level of beauty stereotyping in films ofthe s. notes . we rejected two movies that were selected because the main characters were animated and meaningful attractiveness ratings could not be made. . we also analyzed all characters with only minor discrepancies compared to the af = analyses. for example, the interaction between beauty and decade on characters' outcomes was significant in the w= analysis (p < . ) but failed to approach significance in the a^ = icx) analysis (p = . ). . the correlations between beauty and goodness for the films used in study were: pride ofthe yankees, r= . ; 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( ). the effects of videotape modeling and daily feedback on residential electricity conservation, home temperature and humidity, perceived comfort, and clothing worn: winter and summer. journal of applied behavior analysis, , - . appendix list of films viewed in this study my favorite wife all this and heaven too the ziegfield girl that hamilton woman hold that ghost pride of the yankees my favorite blonde madame curie dragon seed spellbound road to utopia rhapsody in blue caesar and cleopatra a tree grows in brooklyn it's a wonderful life the razor's edge till the clouds roll by night and day key largo the barkleys of broadway all about eve halls of montezuma father's little dividend here comes the groom quo vadis the quiet man ivanhoe stalag sabrina river of no return on the waterfront desiree rear window guys & dolls pete kelly's blues picnic around the world in days the bridge on the river kwai the pride and the passion the horse soldiers lover come back to kill a mockingbird bon voyage days at peking the great escape it's a mad, mad, mad, mad world tom jones the americanization of emily the sons of katie elder a man for all seasons wild angels up the down staircase thoroughly modern millie you only live twice oliver! three in the attic chitty chitty bang bang for love of ivy finian 's rainbow starting over stir crazy tarzan the ape man midnight cowboy big jake sounder the new centurions last tango in paris magnum force the three musketeers herbie rides again jaws the enforcer the omen taxi driver no deposit, no return all the president's men silent movie slap shot star wars turning point heaven can wait grease sudden impact psycho ii gremlins indiana jones and the temple of doom police academy splash cocoon the jewel of the nile witness national lampoon's european vacation heartbreak ridge la bamba throw momma from the train planes, trains, and automobiles beetlejuice die hard parenthood when harry met sally wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ synthese issues/year electronic access ▶ link.springer.com subscription information ▶ springer.com/librarians synthese an international journal for epistemology, methodology and philosophy of science editors-in-chief: o. bueno; w. van der hoek; k. miller ▶ google scholar highest ranking journal in category philosophy ▶ google scholar highest ranking journal in category epistemology & scientific history ▶ % of authors who answered a survey reported that they would definitely publish or probably publish in the journal again synthese is a philosophy journal focusing on contemporary issues in epistemology, philosophy of science, and related fields. more specifically, we divide our areas of interest into four groups: ( ) epistemology, methodology, and philosophy of science, all broadly understood. 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( ), journal citation reports® on the homepage of synthese at springer.com you can ▶ sign up for our table of contents alerts ▶ get to know the complete editorial board ▶ find submission information http://link.springer.com/journal/ http://www.springer.com/librarians http://www.springer.com/philosophy/epistemology+and+philosophy+of+science/journal/ http://www.springer.com/ chickens prefer beautiful humans∗ stefano ghirlanda , liselotte jansson , and magnus enquist , group for interdisciplinary cultural research, stockholm university zoology institution, stockholm university —reprint of april , — abstract we trained chickens to react to an average human female face but not to an average male face (or vice-versa). in a subsequent test, the animals showed preferences for faces consistent with human sexual preferences (ob- tained from university students). this suggests that human preferences arise from general properties of nervous systems, rather than from face-specific adaptations. we discuss this result in the light of current debate on the mean- ing of sexual signals, and suggest further tests of existing hypotheses about the origin of sexual preferences. introduction a widespread idea about sexual signals is that they provide potential mates with detailed information about the signal bearer’s quality as a mate. signalling of both phenotypic and genetic quality (for instance: lack of genetic defects, a good immune system) has been hypothesised (reviewed in andersson, ). the hy- pothesis goes further in assuming that the natural receivers of a signal (that is, conspecifics of the opposite sex) possess a biological adaptation enabling them ∗correspondence: stefano ghirlanda, kräftriket b, s- , stockholm, sweden. email: stefano.ghirlanda@intercult.su.se. first published in human nature ( ), – . c© aldine de gruyter. non-commercial circulation of this paper is unrestricted in any media, provided no fees are requested and no alterations are made. to decode the quality information contained in the signal. such a mate-quality hypothesis has been often embraced in studies on humans (cunningham, ; perrett et al., ; buss, ; thornhill & gangestad, ) whereas it re- mains controversial among biologists studying other species (see e.g. palmer & strobeck, ). an alternative hypothesis (enquist & arak, ; ryan, ) agrees that receivers get some information from sexual signals, e.g. about sex and age, but also claims that finer details of receiver preferences are due to biases inherent to nervous systems. for instance, preferences for exaggerated sex-typical traits (keating, ; gillen, ; perrett et al., ; rhodes et al., ) may fol- low from how the brain discriminates between the sexes (enquist et al., ). indeed, it is typical for biases to emerge as a by-product of some discrimination or recognition task. such biases follow well-known empirical rules which are largely independent of the particular task at hand (that is whether a discrimina- tion has been solved to obtain food, to escape a danger, or, in humans, simply to comply with the instructions of an experimental psychologist, see purtle, ; mackintosh, ). this latter fact suggests a method to distinguish generic biases from prefer- ences shaped by a specific selection pressure. kobayashi ( ) argued that if the bias hypothesis is correct, similar preferences can potentially develop in any nervous system, given experience with the considered signals. in contrast, the mate-quality hypothesis predicts that preferences be species-specific, because they should be tailored to interpret quality cues that differ across species. kobayashi tested this idea by presenting mynhas (gracula religiosa) with pictures of pea- cocks (pavo cristatus), and showing that they preferred to approach and peck at the picture representing the peacock with the most magnificent tail. in this paper we report on a similar experiment comparing human sexual preferences for faces with preferences developed by chickens in the course of a face discrimination task. methods chickens subjects. the experimental animals were six chickens (gallus gallus domesti- cus), of which four females. the animals had experience with the experimental setup (pecking visual stimuli on a computer screen, see below), but not with tasks involving faces. stimuli. a set of seven faces (fig. a) was obtained as follows. average male and female faces were obtained by averaging individual pictures of individuals of each sex. these averages are indicated with an arrow in fig. a. the middle face was obtained by averaging these two averages. finally, we obtained by graph- ical manipulation (linear extrapolation based on pixel patterns) two faces showing exaggerated female traits (shown at the right of the female average in the figure) and two faces showing exaggerated male traits (at the left of the male average). the whole set of faces has been reliably rated as increasing in femininity from left to right by human subjects in another study (enquist et al., ). training. during training the animals saw only the average male and female faces. the faces alternated in random order on a touch-sensitive computer screen (with the provision that a face could not appear more than three times in a row). apart from the face image, the screen was black. hens were rewarded for pecking at the male face, cocks for pecking at the female face. pecks at the rewarded face caused the screen to become white while access to food was allowed for s. if no pecks occurred within s, a new randomly chosen face was shown (after a s interval during which the screen was black). when the unrewarded face was shown, it stayed on the screen until s with no pecks had occurred. animals were trained daily excluding weekends. each training session lasted until the subject stopped responding (criterion: about minutes without any pecks) or after about minutes. animals were motivated by withdrawal of food from their cages to hours before training. training continued until at least % of the total number of pecks was directed to the rewarded face (average of three consecutive sessions). this criterion was reached in an average of . sessions (range – ). testing. during testing the presentation of the rewarded and unrewarded faces continued as above, but every seven presentations of the rewarded face a test trial occurred. during a test trial a randomly chosen face from the whole set in fig. a was shown for s, and the number of pecks to it was recorded. no reinforcement was given on test trials. testing continued until all animals had received at least four presentations of each of the test faces. humans subjects. fourteen undergraduate students in biology (seven females) partici- pated in the study for course credits. a b chickens humans . . . . p ro po rt io n of r es po ns es face figure : a) faces used in the experiment (see text). b) average proportions of pecks by chickens in response to the test faces, and human ratings of the same faces. bars denote se. animal data are aligned so that face is the unrewarded face, and face the rewarded one. for humans, face is the same-sex average and face the opposite-sex one. stimuli. same as for the chickens. training. human subjects received no training. rather, they were shown the faces in fig. a once in random order, immediately before the test. testing. the students were asked to rate, in random order and on a scale from to , all faces in fig. a according to how desirable would it be to go on a date with the portrayed person. each face was shown alone on a computer screen, until the subject rated it. the total scores collected by each face were transformed into relative scores, which allowed comparison with animal data. results and discussion fig. b shows the test results in the form of a generalisation gradient over the whole face set. human and chicken behaviour was almost identical (correlation between the two gradients r = . ). moreover, chicken and human data for each face never differed significantly (two-sample t tests, n = , n = , p values between . and . ). the response gradients in fig. b are as expected based on our general knowledge about learning and memory, simply based on the fact that a discrimination between stimuli has been established (mackintosh, ; enquist et al., ). the agreement between chickens and humans is a further argument to conclude that no deviation from these general rules is present in our human data. thus, the results do not require the assumption of face-specific adaptations in humans. we cannot of course be sure that chickens and humans processed the face im- ages in exactly the same way. this leaves open the possibility that, while chickens use some general mechanism, humans possess instead a specially evolved mech- anism for processing faces. we cannot reject this hypothesis based on our data. however, there are at least two reasons why we do not endorse this argument. first, it is not needed to account for the data. we believe that the existence of a task-specific adaptation can be supported only with proofs for it, rather than with absence of proofs against. second, the evolutionary logic of the argument is weak. from observed chicken behaviour and knowledge of general behaviour mechanisms we must in fact conclude that humans would behave the same way with or without the hypothesised adaptation. there would thus be no selection pressure for developing one. our experiment can be developed in several ways. for instance, we have trained chickens to distinguish between two faces only, while humans have ex- perience of many more faces. to partially compensate for this difference in ex- periences we have used average faces, which encode the characteristics of many individuals. nevertheless, it is certainly desirable to extend our results by train- ing animals to discriminate between the sexes based on individual faces. this would also allow to test preferences with a wider set of faces. moreover, faces of children and old people may also be employed as unrewarded stimuli to better approximate human experiences and investigate preferences with respect to age. if the bias hypothesis is correct, closer and closer approximation of human expe- rience should lead to better agreement between animals and humans with larger sets of faces than the one used here. on the contrary, if systematic differences between humans and animals will emerge, and if the human criteria will be found to match actual mate quality, the mate-quality hypothesis will receive support. ours is of course a preliminary study. we believe, however, that it shows the potentials of the comparative study of preferences. this method is relevant not only to the study of human faces, but can be applied to any communication system to evaluate whether its evolution has favoured information transfer or rather is a product of receiver biases. acknowledgments support from the tercentenary fund of the bank of sweden and marianne och marcus wallenberg stiftelse is gratefully acknowledged. references andersson, m. . sexual selection. princeton, nj: princeton university press. buss, d. m. . evolutionary psychology. the new science of the mind. boston: allyn and bacon. cunningham, m. r. . measuring the physical in physical attractiveness: quasi-experiments on the sociobiology of female facial beauty. journal of per- sonality and social psychology, , – . enquist, m. & arak, a. . neural representation and the evolution of signal form. in cognitive ethology (ed. by r. dukas), pp. – . chicago: chicago university press. enquist, m., ghirlanda, s., lundqvist, d. & wachtmeister, c.-a. . an etho- logical theory of attractiveness. in facial attractiveness: evolutionary, cogni- tive, cultural, and motivational perspectives, volume of advances in visual cognition. westport, ct: ablex. gillen, b. . physical attractiveness: a determinant of two types of goodness. personality and social psychology bulletin, , – . keating, c. . gender and the physiognomy of dominance and attractiveness. social psychology quarterly, , – . kobayashi, t. . do mynahs prefer peacock feathers of more regular pattern? ornis svecica, , – . mackintosh, n. . the psychology of animal learning. london: academic press. palmer, a. r. & strobeck, c. . fluctuating asymmetry and developmental stability: heritability of observable variation vs. heritability of inferred cause. journal of evolutionary biology, , – . perrett, d., lee, k., penton-voak, i., rowland, d., yoshikawa, s., burt, d., henzi, s., castles, d. & akamatsu, s. . effects of sexual dimorphism on facial attractiveness. nature, , – . purtle, r. b. . peak shift: a review. psychological bulletin, pp. – . rhodes, g., hickford, c. & jeffery, l. . sex-typicality and attractiveness: are supermale and superfemale faces super-attractive? british journal of psy- chology, , – . ryan, m. . sexual selection, receiver bias, and the evolution of sex differ- ences. science, , – . thornhill, r. & gangestad, s. w. . facial attractiveness. trends in cognitive sciences, , – . the architecture of subterranean ant nests: beauty and mystery underfoot j bioecon ( ) : – doi . /s - - - the architecture of subterranean ant nests: beauty and mystery underfoot walter r. tschinkel published online: july © springer science+business media new york abstract over the million years of their evolution, ants have constructed or occupied nests in a wide range of materials and situations. a large number of ant species excavate nests in the soil, and these subterranean nests have evolved into a wide range of sizes and architectures. on the basis of casts made of such nests, this variation and the patterns that govern it are described. the possible functions of architectural features are discussed, as are the behavioral “rules” through which the nests are created by worker ants. keywords formicidae · excavation · soil nesting · thermoregulation · division of labor · vertical organization · pogonmyrmex badius · dorymyrmex bossutus · dorymyrmex bureni · prenolepis imparis · solenopsis invicta · atta · cyphomyrmex rimosus · trachymyrmex septentrionalis · monomorium viridum · dolichoderus mariae · formica pallidefulva · formica archboldi · formica dolosa · camponotus socius · camponotus floridanus · pogonomyrmex californicus · odontomachus brunneus · aphaenogaster floridanus · veromessor pergandei · nylanderia arenivaga · pheidole morrisi introduction soil is the medium under our feet, the stuff that we grow our crops in, the foundations for our houses and the basis of all terrestrial ecosystems with their thousands of species. to those animals adapted to live in it, soil is a welcoming medium. it can offer protection from enemies, coddling temperatures, soothing humidity, a refuge b walter r. tschinkel tschinkel@bio.fsu.edu department of biological science, florida state university, tallahassee, fl - , usa http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf w. r. tschinkel from the lethal sunshine and withering heat during the summer, or from paralytic cold during the winter. even when not a drop of liquid water is to be found above ground, the soil can offer drinkable films of life-giving water to animals small enough to exploit it. but most of us rarely give a thought to the many animals that create burrows, homes, galleries, cavities and tunnels in the soil. among the most common soil-dwelling animals in most of the warm areas of the world are the ants, many of which are consummate diggers. all , species of ants are social, living in colonies that function like organisms, in the sense that it is the colony that reproduces, the colony members merely being the gears and levers of this self-reproducing machine. ants, like social wasps and bees, are all-female societies in which the colony is a family and consists of more-or-less sterile workers along with a single individual (or a few) that lays eggs (the queen). this sharp division of labor is further subdivided among the workers on the basis of age. young workers function as nurses caring for their larval sisters. as they age, they take on more general nest maintenance, transport and processing, and only toward the ends of their lives do they leave the nest to forage, bringing food back to be shared among their sisters, and meeting an early death as a consequence. the nesting habits of ants are quite varied, ranging from excavated soil nests, to rotten wood, to cavities in living trees, or even nests constructed of carton. in this essay, we will focus only on nests excavated in the soil, for excavation and construction are fundamentally different behaviors. in the context of biomimicry, the implication is that there is engineering wisdom to be gained from the ants, but it is important to understand that ant nests are evolved not designed. they are not engineered entities such as human houses, bridges and other structures. ant nests, like the ants themselves, evolved over millions of years through the addition of small changes to whatever existed at the time. gradually, species of ants diverged from one another through these incremental changes, gradually producing the modern fauna of about , species, and at the same time, through the same gradual modification of behavior, producing the range of nest architectures we see today. a more complete literature review of ant nest architecture can be found in tschinkel ( ). the ancestral nest what did the ancestral ant nest look like, and how was it modified through evolution? the ancestor of all ants was probably a solitary wasp whose females excavated a nest in the ground in which she raised her offspring (wilson ). sociality evolved when the female and her offspring shared the nest for much of their lives, gradually dividing up the duties of reproduction and work to produce the first ant societies from which all modern ants descended. although we do not have fossils of these ancestral ant nests, we can guess that they probably looked like the nests of many ground-nesting wasps and bees—simple vertical or angled burrows with an enlarged chamber at its lower end, or perhaps several small chambers off the main burrow. just as the evolution of ants began with a single individual, the life cycle of many ants begins by recapitulating what is essentially the ancestral condition—a single mated queen, soon to be mother of a family. this queen digs what is essentially a facsimile of the ancestral nest, a the architecture of subterranean ant nests: beauty and... fig. the majority of subterranean ants nests are composed of variations of the same basic unit, a more- or-less vertical shaft connecting more-or-less horizontal chambers. some of the examples shown are not complete nests, e.g. numbers , and . the nests are not shown to the same scale. inset .it seems likely that all modern ant nests evolved from a simple burrow with one or a few chambers. many modern ant species recapitulate this simple stage during the founding period when the newly-mated queen constructs such a simple burrow-with-chamber. the example shown is of the fire ant, solenopsis invicta simple burrow with a chamber at its end (fig. , inset). after the queen has produced the first brood of workers from reserves stored in her body, these workers enlarge the nest by adding chambers, enlarging chambers and deepening the nest as the colony grows. in a general sense, the nest grows much as it evolved. moreover, its basic unit of structure remains the same in almost all ground-nesting ants—a more or less vertical shaft connecting more or less horizontal chambers (like shish-kebobs, fig. ). in the course of evolution, all elements of this basic unit have been modified to produce the range of nest architectures we observe today. methods for studying nest architecture (tschinkel ): the architecture of subterranean ants nests can be rendered by careful excavation, layer by layer, exposing each chamber in turn. this can reveal the chamber outlines, chamber depth and orientation, but it does not record connecting shafts very well, nor does it record characters such as chamber ceiling height, fine structural details and so on. in contrast, filling the hollow space of an ant nest with a casting material can produce a three-dimensional cast that is faithful in even tiny details. the casting material used will depend on the purpose of making the cast. when the nest contents are to be retrieved, the best material might be paraffin wax (or possibly dental plaster). the wax can be melted or the plaster dissolved to retrieve the ants. when the purpose is simply to render the space visible for a display (e.g. a museum), the best material will be a molten metal, with the ideal being aluminum because of its strength. however, zinc is better for nests with smaller diameter shafts and finer structure. the higher melting point of aluminum means that it cannot cast very fine structures. w. r. tschinkel thus, for most of the life cycle, it is the colony that creates the underground nest. it is one thing to imagine a single animal digging a nest of some specified shape. after all, we can all think of examples. but it is entirely another when the characteristic nest architecture is created by a group of individuals, for they must all respond to each other and to the growing nest in particular ways to produce the consistent outcome we see. this fact is the charming, central mystery of social insect behavior, for everything they accomplish they accomplish without a leader, without a blueprint, without a plan, without prior instruction, and in the case of subterranean ant nests, in the dark, but with a shared set of behavioral rules. in brief, the workers’ behaviors that create the nest are self-organized (rasse and deneubourg ; buhl et al. ). each worker carries within herself the “instructions” of what to do given a certain context, how to interact with other workers and the forming nest, and when to do it. the tasks are carried out in “series-parallel”, that is, each worker does a small part of the job, whereupon another worker may do the next step, while the first responds to something else. because labor is highly redundant, the work gets done in thousands of little steps, eachseemingperhapsundirected,randomorevenbackwards,butstatistically,progress is directional, and the nest gradually appears. there is a broad division of labor that makes some workers more likely to initiate a new nest site, others to dig, to carry sand, to transport brood to the new nest and still others of yet unknown function, yet within these broad categories, workers are interchangeable (beshers and fewell ). in essence, the colony as a whole behaves like an organism (camazine and deneubourg ; hölldobler and wilson ). organisms are entities composed of cells whose cooperation is so well-honed that we fail to recognize them for what they are—the ultimate, perfected self-organized, self-reproducing machines. perhaps we are blinded to this truth by the fact that the cells all stick to one another, whereas the members of an ant colony are free to roam about. yet, to see the colony as a “superorganism” parallel to organisms is to perceive its most fundamental character—an entity whose members all pursue the common goal of self-reproduction. neither the cells of an organism, nor the workers in a colony have a reproductive future save through the entity of which they are a part. our understanding of how self-organization works is dim, but because the nests of ant species occur in a wide range of shapes and sizes, it is clear that subtle evolved changes in worker behaviors and sensory responses produce shifts in self-organization that in turn produce nests that are quite different. this thought should be kept in mind as i describe the variety of architectures across ant species. evolution and range of architectural variation with this background, we can see that most ant nests have been derived from the (pre- sumed) ancestral nest through the addition of chambers, changes in chamber shape and spacing, maximum depth and total chamber area (or volume). these elements seem to have been modified with a large degree of independence from each other, sug- gesting a degree of independence of the self-organizing programs. chamber spacing may be increased or decreased independently of other architectural features (fig. ). chamber outline may be modified with little change in other elements, although there the architecture of subterranean ant nests: beauty and... fig. most elements of the nest architecture seem to be able to evolve more-or-less independently of one another. in this example, the most obvious difference between the nests of monomorium viridum (left) and dorymyrmex bossutus (right) is the spacing between the chambers. the shafts connecting chamber in m. viridum are extremely short, while those in d. bossutus are long is a strong trend for the chamber outlines to become lobed as the ants enlarge them (fig. a, b). maximum nest depth may change with little change in other elements (fig. ). w. r. tschinkel fig. chamber outlines often become more lobed as the chambers are enlarged, but this is not universal. in prenolepis imparis (a), lobes arise even when the chambers are incipient, but in aphaenogaster floridanus (b) even the largest chambers are only moderately lobed the architecture of subterranean ant nests: beauty and... fig. maximum nest depth varies greatly among species, even when other elements are rather simi- lar. dorymyrmex bureni (left), prenolepis imparis (center, tschinkel ) and aphaenogaster floridanus (right) although most of the connecting shafts are more or less vertical, in some species they are distinctly to greatly angled (fig. ). pogonomyrmex badius is a special case of angled shafts, for the shaft is wrapped into a helix (fig. a), a condition that is par- ticularly apparent at depth (tschinkel ). this condition is also apparent in pogon- omyrmex californicus, although the helix is much looser (fig. b) (unpublished data). w. r. tschinkel fig. in some species, the shaft is not vertical, but distinctly angled. this is expressed to an extreme degree in the desert dwelling veromessor pergandei shown here. a a view directly from the side and b a / view showing the chambers in many species, the chambers just below the soil surface are qualitatively different from those at greater depth. in p. badius (fig. a), these near-surface excavations result from the enlargement and branching of horizontal, linear tunnels, eventually creating very large chambers of complex outlines. the deeper chambers begin as rounded circular or oval outlines and become lobed as they are enlarged. it is thus likely that near-surface chambers and deeper chambers result from different behavioral programs (tschinkel ). other examples of such architectural differences in near- surface and deep chambers include prenolepis imparis (fig. ) (tschinkel ), p. californicus (fig. b), f. pallidefulva (mikheyev and tschinkel ), dorymyrmex bureni (tschinkel ) and d. sp. (fig. b, c) (unpublished data). variation of architecture within a genus is particularly interesting because it reveals the relatively recent modifications of behaviors and nest elements leading to distinct architectures among related species. in three species of north florida formica, the the architecture of subterranean ant nests: beauty and... fig. in pogonomyrmex badius, the shaft is also angled rather than vertical, but it is wrapped around an imaginary cylinder to form a helix (a). in (b) p. californicus, the helix is much looser (the cast is incomplete) architecture is distinguished primarily through single versus multiple shafts, angled versus vertical shafts and concentration of chamber area near the surface versus near the bottom of the nest (fig. ) (unpublished data). f. archboldi and f. pallidefulva most commonly have single shafts with a greater concentration of chamber area near the surface, but the shaft is usually vertical in f. archboldi while it is angled in f. pallidefulva. the nests of f. dolosa consist of multiple, mostly angled shafts with chamber area concentrated near the bottom of the nest. the nature of the individual chambers remains similar in all three species—relatively small in comparison to the ants’ body size, simple and rather “clunky.” similar within-genus comparisons can be made for three north florida aphaenogaster species (tschinkel ). although most chambers are flattened in vertical aspect, in some of the fungus gardening ants, the chamber shape has been converted from the widespread pancake shape to egg shaped (fig. ) (tschinkel ; moreira et al. a,b; solomon et al. w. r. tschinkel fig. near-surface chambers in some species are qualitatively different than deeper chambers in that they are more like branching horizontal tunnels rather than enlarged ovals. a p. badius (tschinkel ), b dorymyrmex sp. and c dorymyrmex bureni ; rabeling et al. ), showing that even this element is mutable. the egg-shaped chambers accommodate the fungus gardens (fig. , inset). some species seem to have abandoned highly regular architecture entirely, as for example the fungus gardener, the architecture of subterranean ant nests: beauty and... fig. within the genus formica, the elements that differ among these three species are the number and angling of the shafts, and the concentration of chamber area near the top or bottom of the nest cyphomyrmex rimosus and the florida carpenter ant, camponotus floridanus (fig. ) (unpublished data). even the argentine ant, linepithema humile has tendencies in this direction (unpublished data). species of nylanderia seem to forgo excavating w. r. tschinkel fig. in the fungus gardening trachymyrmex septentrionalis, the chambers are egg-shaped rather than flattened in order to accommodate the fungus gardens (inset) distinct chambers, creating only lateral bulges in their vertical shafts (fig. ). on the other hand, they consistently construct a second vertical shaft that does not connect directly to the surface, but rather to the primarily vertical shaft (unpublished data). dolichoderus mariae appears to have abandoned all pretenses of aesthetics and simply excavates the soil under grass clumps to form a large, irregular cavity exposing the grass roots that the colony then uses as a scaffold on which to hang itself and its brood (fig. ) (laskis and tschinkel ). nest growth during the life cycle and colony growth, all elements of the nest are enlarged so that the proportions of the elements to each other remain more or less constant (fig. ) (tschinkel , ). it is the conservation of these proportions, no matter what the architecture of subterranean ant nests: beauty and... fig. in some species, such as the fungus gardener cyphomyrmex rimosus, the architecture lacks reg- ularity and appears to consist of rather haphazard shafts without distinct chambers. this is also seen in camponotus floridanus (inset) the size or stage of development, that creates the species-typical nest architecture. in addition to such growth of the basic nest unit, some species enlarge the nest by adding shish-kebab units to make nests composed of multiple units. spacing between units can be considerable, as in p. badius (fig. a) (tschinkel ), minimal as in ph. morrisi (fig. b) (unpublished data) and touching as in the fire ant, solenopsis invicta (fig. c) (cassill et al. ). an interesting consequence for the first two is that in order to move between the vertical units, ants must travel to the near-surface before descending into another unit. what consequences this might have for colony organization and function is unknown. in all species, the nest is enlarged as the colony grows, but the total chamber area and depth may grow faster, slower or at the same rate as the number of workers. when the growth rate of the two is different, the ants may become, on average, more crowded or less crowded, with unknown consequences for social interaction. however, the meaning of this overall density is not clear because in most species, the ants are generally more crowded deep in the nest, and also move up and down within the nest to track environmental conditions (penick and tschinkel ). it should be no surprise that the total size of subterranean ant nests is generally related to both the size of the colony that built it and the size of the ants that live within it. this suggests that there is feedback from the nest size to the worker behavior such that nest enlargement reaches a limit set by the colony size. such feedbacks can apply w. r. tschinkel fig. nylanderia arenivaga nests lack distinct chambers but always have the second shaft connecting to the main shaft by a lateral tunnel. this cast is incomplete not only to the whole nest, but also to different levels, assuring that certain architectural proportions are preserved. ant nests range from thimble sized to the truly monumental excavations of the higher fungus gardening ants in the genus atta (jonkman a,b; moreira et al. a,b). figure shows nests built by approximately monomo- rium viridum, a very small ant, pheidole morrisi, a medium-sized ant, and p. the architecture of subterranean ant nests: beauty and... fig. the polygyne, polydomous ant dolichoderus mariae simply excavates the soil beneath grass clumps and uses the exposed roots as a scaffolding on which to hang the workers and brood (laskis and tschinkel ) badius, a large ant. larger ants need larger diameter shafts and higher chamber ceilings than do smaller ones. moreover, at the same level of crowding, larger ants will dig larger chambers than smaller ants. whether there are general rules that apply across ant body sizes is yet unknown, but there ought to be a fairly tight relationship between shaft diameter, chamber area, ceiling height and the body size of the ants. from an energetic investment point of view, there should be an optimum relationship among these variables. smaller dimensions would create crowding that could interfere with efficient movement and work, whereas larger values would expend unnecessary energy in soil removal and transport. function and organization of work because ant nests have evolved to be species-typical, it is reasonable to assume that the architecture is functional. of course the most basic functions of shelter, defense and microclimate are obvious and need hardly be pointed out. what is meant here is that, in some as yet unclear way, the particular features of architecture enhance the colony’s fitness by acting on some aspect of production or efficiency. perhaps a particular distribution of vertical chamber area, chamber shape or spacing between chambers, or total area or maximum depth, maximizes fitness by allowing the production of more sexual alates, or their production at lower cost. brian ( ) showed that work-group efficiency declined as group size increased, suggesting a possible function for chamber size. experiments with the fire ant, solenopsis invicta, supported the hypothesis that chamber size may be important to colony efficiency. in laboratory experiments, the efficiency with which workers reared brood (i.e. new workers per old worker per month) decreased as the size of the worker group increased (michener ; porter w. r. tschinkel fig. during colony growth and nest enlargement, all elements of the nest architecture are simultaneously enlarged, thus preserving the proportions and giving the nest its species-typical appearance. the example shown here is camponotus socius (tschinkel ) and tschinkel ; karzai and wenzel ). however, in natural colonies of the fire ant, larger colonies reared brood just as efficiently as did smaller ones (tschinkel ). natural nests are composed of dozens to hundreds of chambers averaging about cm , limiting the size of the work group to about ants (cassill et al. ), far smallerthanthelaboratoryexperiments.thissuggeststhatoneeffectofthesubdivision of the natural nests into many chambers is to limit the size of the work groups and thus to maintain a high brood-rearing efficiency. whether this is true of other ant species is not known. another example of function is suggested by the upward movement of aging work- ers in harvester ant nests (and many other ant species) (mackay ; tschinkel ; hart and tschinkel ; kwapich and tschinkel ). brood are found primarily in the bottom third or so of the nest, seeds in a zone above that but still well below the surface, and foragers only in the top – cm. young workers engage in brood care and are found mostly in the bottom third of the nest, middle aged workers take on several maintenance, transport and processing duties in the middle regions and only older workers act as defenders and foragers at the top. the upward movement com- bines with the vertical nest structure to separate each set of duties into different zones of the nest in an assembly line fashion. this linear separation probably increases the the architecture of subterranean ant nests: beauty and... fig. three examples of nest enlargement among species with multiple-shaft nests. the nest is enlarged duringcolonygrowthinpartbyaddingmoreshish-kebabunits,butalsobyaddingmorechambers,deepening the nest and enlarging chambers. a p badius (tschinkel ), b ph. morrisi and c s. invicta w. r. tschinkel fig. nests vary enormously in total volume according to species and body size of the ants. all of three of these nests housed approximately – ants. the nest of the tiny ant monomorium viridum is much smaller than that of the medium sized pheidole morrisi, which in turn is much smaller than that of the large ant p. badius efficiency of a number of colony functions just as a factory assembly line increases the efficiency of automobile production. although it may not be possible to attribute this presumed efficiency to any specific architectural feature, the vertical spread of many ant nests suggests similar segregation of work duties. even ants with simple, single-chamber nests between stones show a centripetal movement of aging workers away from the central brood pile (sendova franks and franks ). the architecture of subterranean ant nests: beauty and... the nest also provides the ants with a range of microclimates and temperatures, a range which most ants seem to exploit by moving themselves and their brood into zones with favorable temperatures and humidities (penick and tschinkel ). in the fire ant, solenopsis invicta, construction of the heat-collecting mound has been shown to provide an approximately % brood production benefit (porter ). many species of ants move brood into and out of near-surface chambers or under stones on a daily cycle to track favorable brood-rearing conditions. much more mysterious is why a lobed chamber should provide some benefit over a simple oval one, or why variable spacing between chambers might be beneficial. other features of mysterious possible benefit include the maximum depth of the nest, and the top-heavy nature of many nests, that is, the disproportionate amount of chamber area nearthesurface.ofcourseitispossiblethatsomefeatureshavenodemonstrablefitness effects, and are simply meaningless epiphenomena of the behavioral mechanisms that created the nest. it is unlikely that every architectural detail is functional, or at least, it would be extremely challenging to test such details. in order to create the vertically structured nests of many species, the ants must possess information with respect to their current depth below the surface. such infor- mation is also necessary for the vertical arrangement by worker age. tschinkel ( ) proposed that soil carbon dioxide gradients could provide such information, but his experiments later showed this not to be true (tschinkel ). nest excavation in harvester ants occurs in part through a chain of transport in which a pellet of soil is removed, moved upward, deposited and picked up by different workers until it is finally deposited on the soil surface (rink et al. ). most of how ants construct nests is still a mystery, although a few hints do exist. although termites construct rather than excavate their nests, the same behaviors basic to self-organization can result in pil- lars, walls, galleries or chambers depending upon pheromonal and air flow conditions (bonabeua et al. ). one can imagine that the basic ant behaviors of digging, pellet formation, pellet transport and deposition could be elicited and modified by varying local conditions to produce nests of a particular architecture. does ant nest architecture offer wisdom for humans? what might ant nest architecture have to offer humans? no doubt, when rendered visible by casting, the nests present appealing objects of great beauty. appreciation is enhanced by the knowledge that the ants constructed these nest in the dark, without a leader and without a plan. few humans live underground, and when they do, as in the loess areas of tunisia and northern china, the architectural rules of excavation seem largelyinspiredby“normal”houseswhosespacesaresimplycreatedunderground.the excavated cities of cappadocia in turkey seem more ant-like in flavor with much less resemblance to “normal” houses and more to ant nests. moreover, from a human point of view, the evolved nests of ants have features that engineered human space would strictly avoid. an architect who built a tall building in which inhabitants have to take the elevator all the way to the top in order to access an adjacent series of rooms below would have a short career. on the other hand, designing rooms of sizes appropriate to their purpose is already very much a part of human architecture. perhaps someday w. r. tschinkel an adventurous architect will design structures containing rooms without corners and with strongly lobed outlines. whether humans would find benefit or pleasure in such rooms will have to be seen. on the other hand, the self-organization of the ants that produces the nests has much to offer humans in the sense of self-recognition. studying self-organization in ants can make us aware that much of human activity is also self-organized, that is, that the tasks are accomplished by competent, distributed agents operating under a shared set of rules and interacting directly with the task itself. in humans as in ants, intense communication is not necessary to get the job done, and the outcome is to varying degrees an emergent phenomenon. this is apparent at the scale of economies, but also operates at many scales in human societies. it seems likely that we overestimate the importance of hierarchy and underestimate that of self-organization in human societies. thus, we might profit from careful analysis of how leaderless groups of individuals with shared behavioral programs, be they ants or humans, interact to get the job done. what subtle cues, changes of venue, current job status, signals and elapsed time cause human or ant workers to change from one task to another, or to stop working? how do these shifts affect the rate and efficiency of work? how does the efficiency and proficiency of workers change with age and experience? and finally, if we view human group tasks as if they were being accomplished by ants, could we gain insight into how humans work? references beshers, s. n., & fewell, j. h. 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( ). subterranean ant nest architecture: trace fossils past and future? paleogeography, paleoclimatology and paleoecology, , – . tschinkel, w. r. ( ). the nest architecture of the florida harvester ant, pogonomyrmex badius. journal of insect science, , . http://jinsectscience.oxfordjournals.org/content/ / / . tschinkel, w. r. ( ). the nest architecture of the ant, camponotus socius. journal of insect science, , . tschinkel, w. r. ( ). methods for casting subterranean ant nests. journal of insect science, , . http://jinsectscience.oxfordjournals.org/content/ / / . tschinkel, w. r. ( ). the nest architecture of three species of aphaenogaster in north florida. journal of insect science. http://jinsectscience.oxfordjournals.org/content/ / / . tschinkel, w. r. ( ). florida harvester ant nest architecture, nest relocation and soil carbon dioxide gradients. plos one, , . wilson, e. o. ( ). the insect societies. cambridge, ma: harvard/belknap. http://jinsectscience.oxfordjournals.org/content/ / / http://jinsectscience.oxfordjournals.org/content/ / / http://jinsectscience.oxfordjournals.org/content/ / / http://jinsectscience.oxfordjournals.org/content/ / / http://jinsectscience.oxfordjournals.org/content/ / / http://jinsectscience.oxfordjournals.org/content/ / / the architecture of subterranean ant nests: beauty and mystery underfoot abstract introduction the ancestral nest evolution and range of architectural variation nest growth function and organization of work does ant nest architecture offer wisdom for humans? references sÖz varliĞi turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer gÜzellİk, aŞk ve bİlgİ ÜÇgenİnde “Şem ve pervÂne” ayşegül akdemİr  Özet tasavvufi düşünce sisteminde “aşk”, allah‟ın yaratıcı etkinliği olarak karşılık bulmakta; “bilgi” ise söz konusu etkinliğin gayesini ve sonucunu ifade etmektedir. hem aşkın hem de bilginin ortaya çıkabilmesi için, “âşık- maşuk” ve “bilen-bilinen” olmak üzere iki unsurun varlığına gereksinim duyulması ise söz konusu kavramların ortak noktasını teşkil etmektedir. en temel kavramı “aşk” olan klasik türk edebiyatında, “âşık/bilen” ve “maşuk/bilinen” ikilisini karşılamak ve bunlar arasındaki ilişki biçimini yansıtmak üzere çeşitli unsurlardan faydalanılmıştır. Çalışmamızın konusunu teşkil eden “şem„ ve pervâne” ikilisi de klasik türk edebiyatında, “âşık/bilen-maşuk/bilinen” ikilisini ve ilişkisini anlatmada kullanılan sembolik unsurlardan biridir. bu unsurlardan “pervâne”, âşığı temsil ederken “şem„ ” ise maşuk fonksiyonunu yüklenmiş durumdadır. bunların şiir dünyası içinde kendilerine bu şekilde bir yer bulmuş olmaları ise söz konusu iki unsur arasındaki ilişki biçiminin, aşk ilişkisi şeklinde yorumlanmış olmasının bir sonucudur. tasavvufi düşünce sisteminde aşk, sadece insanı değil, insanı olduğu kadar yaratıcı‟yı da ilgilendiren bir kavram olarak ele alınmıştır. buna bağlı olarak “şem„ ve pervâne” sembolizminde de aşk, her iki unsur için de geçerli bir kavram olarak karşımıza çıkmakta ve söz konusu iki aşk, varlık halkasının birbirini takip eden iki aşamasını meydana getirmektedir. bu halkanın ilk yayını şem„in yanışı oluştururken ikinci yayını ise pervânenin yanışı oluşturmaktadır.  arĢ. gör., fırat Üniversitesi fen edebiyat fakültesi türk dili ve edebiyatı bölümü. ayse.akdmr@mynet.com ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bu çalışmada, klasik türk edebiyatının sembolik ifadelerinden olan “şem„ ve pervâne” ikilisi; “güzellik”, “aşk” ve “bilgi” kavramları çerçevesinde ele alınmış ve tasavvufi düşünce sisteminin ışığında yorumlanmaya çalışılmıştır. anahtar kelimeler: Şem„, pervâne, güzellik, aşk, ateş, bilgi. “Şem and pervane” in the triangel of beauty, love and knowledge abstract in the sufism thought system “love” means the creative activity of allah; but “knowledge” means the aim and result of the activity mentioned. to cause both love and knowledge appear, two elements known as “lover- love” and “knowing-known” are needed because they consist of joint point of the concepts mentioned. in the classical turkish literature whose main concept is love several elements are taken into consideration to meet “the lover/knowing” and “the love/known” and to reflect the form of the relation between them. “Şem and pervane” which is the main subject of our study is one of the sembolic elements used in expressing the relationship of “the lover/knowing-the love/known” in the classical turkish literature. among these elements “pervane” represents the lover and “şem” undertakes the function of maşuk. the fact that these elements take place in the world of poetry is because the form of the relationship between these two element are commented as the love relation. in the sufism, love is taken into consideration as a notion which is related to not only human but also the creator. therefore, love in the “şem and pervane” symbolism faces us valid for both two elements and the two love mentioned forms the two steps following each other in the coil of the existence. the first ring of this coil is the burning of şem and the second is the burning of pervane. güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer in this study, “şem and pervane” which are the symbolic expressions in the classical turkish literature are taken into consideration through the concepts of “beauty”, “love” and “knowledge” and they are commented in the light of sufism thought system. key words: Şem, pervane, beauty, love, fire, knowledge. Ġslam‟ın iç yüzü, bâtıni boyutu olan tasavvufi düĢünce sistemini, “bilinen (maddi, zâhiri)” olandan “bilinmeyen (manevi, bâtıni)” olana doğru yapılan bir yolculuk ya da bunlardan ilk grubu oluĢturanların ikinci grubu oluĢturanlara dönüĢümü Ģeklinde değerlendirmek mümkündür. bu dönüĢüm, çok büyük ölçüde tasavvufi düĢünce sistemiyle beslenmiĢ olan klasik türk edebiyatının diline de doğrudan yansımıĢ ve bu dile, maddi âlemden manevi âleme doğru uzanan bir köprü olma niteliği kazandırmıĢtır. zira dikkatini madde âleminden mana âlemine çevirmiĢ olan klasik türk edebiyatı Ģairinin dili, her ne kadar sıradan bir dil gibi görünse de aslında “bilinen (maddi, zâhiri)” olan vasıtasıyla, “bilinmeyen (manevi, bâtıni)” olanı anlatmayı hedeflemiĢ çift katmanlı bir dildir. latîfî, klasik türk edebiyatında kullanılan dilin bu özelliğini, klasik türk Ģiirine yaklaĢım biçimimizin nasıl olması gerektiği konusunda bir uyarı niteliği taĢıyan sözleriyle Ģu Ģekilde ifade etmektedir: “aslında, Ģâirlerin mecazî Ģiir örtüleri ve gerçeği iltibaslarında def, ney, sevgili ve Ģarabı gösteren ibare ve istiareler gelirse, görünüĢe bakıp bunları Ģarap, dilber, kol ve boy övgüsü olarak düĢünmemek lazımdır. tasavvuf [erbâbının] ve gerçek[i] bilenlerin dilinde her sözün bir mânâsı, her ismin bir müsemması, her sözün bir tevili ve her tevilin bir temsili vardır. (…) sözün kısası bunlar ister güzelleri medh etsin, isterse dilberleri övsün hakk‟ı görebilen gerçek erlerle vahdete ulaĢmıĢ allah dostlarının yolunda gidenler, onları celâl ve cemâl sahibi yüce allah‟a ait görürler” ( , - ). ġiir dilinin bu özelliği, “söylenen” ve “kastedilen” olmak üzere bir ikiliğin ve ayrımın ortaya çıkmasına da zemin hazırlamaktadır. dolayısıyla da klasik türk Ģiirinde “söylenen” baĢka, “kastedilen” ise baĢka bir Ģey olmaktadır. bu ikisi arasındaki mesafe ise dönemden döneme veya Ģairden Ģaire değiĢkenlik gösterebilmekle beraber, söz konusu mesafenin hiçbir zaman kapanmaması, klasik türk Ģiirinin genel niteliğini teĢkil etmektedir. ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer ġiirlerinde, “söylenen” ve “kastedilen” arasındaki mesafeyi çoğu zaman oldukça geniĢ tutmuĢ bir Ģair olan ġeyh gâlib, okuyucuya kılavuz olmak istercesine bu gerçeğe iĢaret eder. onun Ģiirleri, gerçek anlamıyla değerlendirilmemelidir. Çünkü söyledikleri baĢka, kastettikleri ise baĢka Ģeylerdir: eğer desem ki havâlar açıldı geldi bahâr murâd odur ki benimle mahabbet eyledi yâr ya söylesem ki çemen goncalarla zeyn oldu odur garaz ki tebessümle söyledi dildâr ġeyh gâlib (kt/ ) gâlib, bu uyarıyı her ne kadar sadece kendi Ģiiri için yapmıĢ olsa da söyledikleri, klasik türk edebiyatı dairesinde yer alan tüm Ģiirler için genelleĢtirilebilir niteliktedir. buna göre, klasik türk Ģiirinin dili çift katmanlıdır; ama bu katmanlardan asıl olan, kelimelerin gerçek anlamlarıyla ilgili olan katman değil, bu kelimeler vasıtasıyla ortaya konulan mecazi anlam veya anlamlardır. o, baĢka bir beytinde Ģiir dilinin bu özelliğini, Ģiir (sühan) ve bir yüzü sarı diğer yüzü ise kırmızı renkte olan ve bu nedenle de “iki yüzlü” olarak nitelenen “gül-i ra„nâ”yı iliĢkilendirerek ifade eder. ancak bu kez, söylediklerini kendisiyle sınırlandırmaz. ġiir dili, çift katmanlı yapısıyla, bir yüzü sarı diğer yüzü ise kırmızı renkte olan “gül-i ra„nâ” gibidir ve gerçek ve mecazi anlam, tıpkı iki yüzü farklı renkte olan bir gül yaprağı gibi, ayrıĢtırılamaz bir bütünlük meydana getirmektedir: sühan olup gül-i ra„nâ-yı reng [ü] bû gâlib ne denlü varsa hakîkat mecâz matlabdır ġeyh gâlib (g / ) gâlib, bu beytiyle genelde klasik türk edebiyatı Ģairinin, özelde ise kendisinin Ģiir anlayıĢını da ortaya koymuĢ olmaktadır: gerçek Ģiir, tıpkı bir “gül-i ra„nâ” gibi iki renkli/çift katmanlı olmalıdır. ya da tek renkli/tek katmanlı olan Ģiir, gerçek Ģiir değildir. Çünkü Ģiir, bütün güzelliğini, iki renkli/çift katmanlı yapısından alır. nitekim gülün ve dolayısıyla da gerçek Ģiirin sıfatı durumunda olan “ra„nâ”nın bir diğer anlamı da “güzel, latif, hoĢ”tur. gül-i ra„nâ ile Ģiir arasında kurulan benzerlik, her ikisinin de “iki renkli” olmasına dayanmaktadır ki klasik türk edebiyatındaki söz konusu bu “iki renklilik”, temelde aĢk kavramının çeĢitliliğine dayanmaktadır. zira aĢk, her ne kadar özünde tek de olsa ortaya çıkıĢ biçimi ve yöneldiği arzu nesnesinin farklı olmasına bağlı olarak “beĢeri/mecazi” ve “ilahî” olmak üzere kategorize edilmektedir. güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer klasik türk edebiyatında ise aĢk, çoğu zaman beĢeri/mecazi ya da ilahî olarak kategorize edilmeye imkân vermeyecek bir Ģekilde iĢlenmiĢ olarak karĢımıza çıkmaktadır. bu ise anlamı belirsizleĢtirmekte ve Ģiiri, hem beĢeri/mecazi aĢkın hem de ilahî aĢkın sınırlarına dâhil olabilecek Ģekilde yorumlanmaya müsait bir duruma getirmektedir. böylece, aĢk kavramının klasik türk Ģiirindeki iĢlenme biçimi ve gül-i ra„nâ, iki farklı “reng”i ayrıĢtırılamaz bir biçimde bütünleĢtirmiĢ olma noktasında birleĢmektedirler ki bu durum, beĢeri/mecazi ve ilahî aĢkın tıpkı gül-i ra„nânın iki yüzündeki iki farklı renk gibi bütün ve ayrıĢmaz olmasının bir sonucu durumundadır. baĢka bir deyiĢle, “insanî aĢkın ve ilahî aĢkın bir tek aĢkın iki ayrı yüzü ol(ması)” (settârî , ) hususu, Ģiire de tıpkı bir gül-i ra„nâ gibi iki renkli/çift katmanlı olma özelliği kazandırmaktadır. aĢkın ve buna bağlı olarak da Ģiirin çift katmanlı yapısı, aslında bir taraftan “mutlak güzellik”in klasik türk edebiyatında beĢeri bir güzellik Ģeklinde tasvir edilmiĢ olmasının, diğer taraftan ise biri ilahî diğeri insani olmak üzere bitiĢik iki ilkeden mürekkep olan insanın (livingston , ) çifte bir doğaya sahip olmasının bir sonucu durumundadır. zira ölümlü (beden) ve ölümsüzü (ruh) bünyesinde birleĢtirmesi bakımından iki kutuplu bir doğaya sahip olan insanın yöneliĢleri de daima doğasındaki bu çift yönlülüğe paralel olarak iki yönde olmaktadır. ancak klasik türk edebiyatında hâkim durumda olan anlam, aĢkın ilahî boyutuyla ilgili olan anlamdır. nitekim andrews, “herhangi bir Ģiirde tasavvufî-dinî yorumun üstünlüğü, birincilliği sorgulanabilir, ama böyle bir yorum potansiyeli barındırmayan bir Ģiir bulmak güçtür” ( , ) derken tasavvufi düĢüncenin klasik türk edebiyatındaki hâkimiyetini açıkça ifade etmektedir. Özü gereği iki kiĢiyi ilgilendiren aĢk, “âĢık” ve “maĢuk” olmak üzere iki unsurun varlığını gerekli kılar. temel kavramı aĢk olan klasik türk edebiyatında, bu iki unsuru karĢılamak ve bunlar arasındaki iliĢki biçimini yansıtmak üzere çeĢitli unsurlardan faydalanılmıĢtır. ÇalıĢmamızın konusunu teĢkil eden “Ģem„ ve pervâne” ikilisi de klasik türk edebiyatında, âĢık-maĢuk ikilisini ve iliĢkisini anlatmada kullanılan sembolik unsurlardan biridir. bu unsurlardan pervâne, âĢığı temsil ederken Ģem„, yani mum ise maĢuk fonksiyonunu yüklenmiĢ durumdadır. bunların Ģiir dünyası içinde kendilerine bu Ģekilde bir yer bulmuĢ olmaları, söz konusu iki unsur arasındaki iliĢki biçiminin aĢk iliĢkisi Ģeklinde yorumlanmıĢ olmasının bir sonucudur. bu Ģekilde bir yorumlamaya sebep ise pervânenin, mumun/sevgilisinin ateĢinde yanarak canını feda etmesidir. zira ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer gerçek bir âĢık olmanın yegâne Ģartı, sevgili uğruna canını feda edebilmektir: „iĢka tanıĢık sıgmaz degme cân göge agmaz pervâne gibi oda yanmayan „âĢık mıdur yunus emre (g / ) aĢkın öznesi (fâili) durumunda olan “âĢık”, klasik türk edebiyatının dünyası içinde Ģairin kimliğiyle özdeĢtir. buna bağlı olarak da sevgilisinin uğruna canını feda etmesi bakımından gerçek âĢığın temsilcisi durumunda olan pervâne, Ģair/âĢık için bir örnek teĢkil etmektedir: ne denlü nâ-tüvân olsam da kaçmam „aĢkdan yahyâ tutuĢdı Ģem„ ile gördüm o lâgar tenle pervâne ġeyhülislâm yahyâ (g / ) ġair/âĢık da tıpkı bir pervâne gibi, sevgili uğruna canını feda etmelidir. Çünkü vuslat, ancak bu sayede mümkün olabilecektir: cihân ü cânı terk et yâr vaslı için ki pervâne aramaz vasl Ģem„a geçmeyince per ü bâlinden ahmet paĢa (g / ) cânumı pervâne tek yandururam Ģem„a kim yanar imiĢ yâr içün vâsıl olan yârına nesîmî (g / ) ġairler, bazen de pervâneyle kendi durumları arasında dıĢ görünüĢe dayanan bir benzerlik kurmuĢ ve bu benzetmenin yönünü de ortaya koymuĢlardır. zayıf bedeni ve vücudundaki siyah yanık yaralarıyla ya da gönlündeki aĢk ateĢi sebebiyle, vücuduna saplanmıĢ olan oklar tutuĢmuĢ olan Ģair, yanmıĢ bir pervâne görünümündedir: dâğ-ı siyehler ile cism-i nizâr u zerdi bir bâl ü peri yanmıĢ pervânedür sanurlar bâkî (g / ) sûzândır odumdan tenime sancılan oklar pervâneyim ey Ģem„ tutuĢmuĢ per ü bâlim fuzûlî (g / ) yukarıda da bahsetmiĢ olduğumuz gibi aĢk, beĢeri/mecazi ve ilahî olmak üzere iki Ģekilde ortaya çıkabilmesi bakımından “iki renkli/yüzlü” bir nitelik taĢımaktadır. dolayısıyla da beĢeri/mecazi aĢk söz konusu olduğunda iki insan arasındaki duygusal yakınlığı ve bağlılığı ifade eden aĢk, ilahî boyutuyla düĢünüldüğü zaman ise insan ve allah arasındaki yakınlığı karĢılar duruma gelmektedir. bu ise güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer aĢkın öznesi ve nesnesi durumunda olan âĢık ve maĢuğun da kimliklerini değiĢtirmekte ve onları, “sâlik” ve “allah”la eĢdeğer duruma getirmektedir. mehmet kanar, “Ģem„ ile pervâne mazmunları, tasavvuf sahasında sık sık iĢlenmiĢ; „pervâne‟, tasavvuf yolunda ilerleyen, makamdan makama geçen; ama vuslata ermek, bir baĢka deyiĢle, fenâfillâh mertebesine ulaĢmak için çeĢitli engellerle karĢılaĢan sâlike benzetilmiĢtir. „pervâne‟nin mum[un] etrafında döndükten sonra kendini aleve atarak yok etmesi ve vuslata ermesi, ikilikten kurtulup vahdete ulaĢması, sûfî Ģairler için orijinal bir konu teĢkil etmiĢtir” ( , ) derken Ģem„ ve pervâne arasındaki iliĢkinin, klasik türk edebiyatında ilahî aĢkla ilgili olarak tasavvur edilmiĢ olduğuna iĢaret etmektedir. neden böyle olduğu sorusunun cevabını ise bize, klasik türk edebiyatında en çok kullanılan benzetmelerden olan “aĢk-ateĢ” benzetmesinin altında yatan gerçeklikler vermektedir. zira pervâneyi sâlikle özdeĢleĢtiren Ģey, ilahî aĢk ve ateĢin her ikisinin de benzer özelliklere sahip olması ve benzer sonuçlar ortaya çıkarmasıdır. Ġlahî aĢk ve ateĢ arasındaki en önemli benzerlik, her ikisinin de değiĢtirici, dönüĢtürücü bir güce/etkiye sahip olması bakımındandır. zira ilahî aĢk; değiĢtiren, dönüĢtüren, arındıran özelliğiyle ateĢin ta kendisidir. yakar, yok eder. böylece ikiliği birliğe dönüĢtürür: “aĢkın ateĢi, insanın putlarını, onu hakikatten alıkoyan maddî heveslerini yıkar. böylece onu temizler. aĢkın ateĢi, insanı tefrikadan ve çeĢitli Ģekillerden alıp birliğe ve hakikî istikrara; çokluktan, Ģirkten kurtarıp tevhid ve birliğe sürükleyen bir kuvvettir. akıl, insana varlık kazandırır. aĢk ise insanın varlığını ortadan kaldırır. Ġnsanın varlığı kaldığı müddetçe de birlik olmaz. Ġkilik olur. biri allah‟ın varlığı, diğeri de insanın varlığıdır. hâlbuki hedef birliktir. o halde insanın birliğe ulaĢması için aĢk gerekir” (düzen , ). bu da mevlânâ‟nın, tedrici bir Ģekilde gerçekleĢen manevi yolculuğunu neden “hamdım, piĢtim, yandım.” Ģeklinde ifade etmiĢ olduğunu anlama noktasında oldukça önemlidir. zira insanı putlarından, maddi bağlarından kurtararak hakikate taĢıyacak olan Ģey, aĢk ateĢidir: ÂteĢ-i „aĢkda mahv etmeğe çâr „unsurunu dört yanından kemer-i gayreti merdân kuĢanır ġeyh gâlib (g / ) klasik türk edebiyatında, pervânenin mumun ateĢinde yanmasının nedeni sorgulanmamıĢ; sonucu ve değeri üzerinde yoğunlaĢılmıĢtır. zaten böyle bir sorgulama, pervânenin bu noktada bir iradesi olduğu, dolayısıyla da seçme hakkına sahip olduğu Ģeklinde bir varsayıma dayanır. oysa yanmak, onun için bir tercih değil, ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer kaderdir. Çünkü o, yanmaya programlanmıĢtır. dolayısıyla da pervânenin durumunu, “kendini yakmak” olarak değil, “yanmak” Ģeklinde ifade etmek gerekmektedir. Çünkü “kendini yakmak” Ģeklindeki bir ifade tarzı, pervânenin yanıĢının bir tercihin sonucu olduğu anlamına gelmekte, bu ise yaĢamın kanunları ve canlı varlıkların doğasıyla örtüĢmemektedir. zira bir canlının kendi varlığı, “yakmak” fiiline nesne olabilecek en son Ģeydir. dolayısıyla aĢk ve ateĢ arasında kurulan benzetmenin baĢka bir boyutu da her ikisinin de “irade”yi dıĢlayan Ģeyler olmasıyla ilgilidir. ahmed gazzâlî, “aĢk öyle bir „cebr‟dir ki onda kesb ve yolun hiç bir önem ve yetkisi yoktur. ġüphesiz onun ahkâmı da bütünüyle „cebr‟dir. onda ve velâyetinde (hüküm alanında) irade ve ihtiyardan söz edilemez. onun velâyetinde irade kuĢu kanat çırpamaz.” ( , ) Ģeklindeki ifadeleriyle, aĢkın gayr-i iradi bir Ģekilde ortaya çıkan ve yaĢanan bir Ģey olduğunu açıkça ortaya koymuĢ olmaktadır. Çünkü aĢk rüzgarı (hevâ) esince akıl mumunu söndürmektedir. yani aĢk gelince akıl devre dıĢı olmaktadır: yine ben dil Ģem„ini bir dil-bere yandırmıĢam ol hevâ ile çerâğ-ı „aklı dinlendirmiĢem zâtî (g / ) dolayısıyla diyebiliriz ki klasik türk edebiyatı Ģairleri, pervânenin mumun alevinde yanmasını “aĢk” Ģeklinde yorumlayarak aĢkla ilgili bir baĢka gerçeğe daha iĢaret etmiĢlerdir: aĢkın olduğu yerde, iradeden bahsetmek mümkün değildir. Ġrade ise aklın tezahürüdür. dolayısıyla aĢk, bir nevi “delilik” hâlidir. bu nedenle de klasik türk edebiyatında çoğu zaman “cünûn (delilik)” olarak karĢılık bulmaktadır: kevser-i âteĢ-nihâdın adı eĢk dûzah-ı cennet-nümânın adı „aĢk bir lügat gördüm cünûn isminde ben anda hep cevr ü cefânın adı „aĢk ġeyh gâlib (kt/ ) “Öteki âleme, ancak bu dünyayla herhangi bir iliĢki içinde lekelenmemiĢ daha yüksek bir akıl seviyesi aracılığıyla eriĢilir; bu nedenle, öbür âleme eriĢme çabası, gündelik hayatta akılcı sayacağımız yolun tam karĢıtıdır” (andrews , ). dolayısıyla aĢkın aklı dıĢlaması neticesinde ortaya çıkan “delilik” hâli, pervâneyi/sâliki birliğe (ruh/yanak) taĢıyacaktır: yakıĢır ruhlarının Ģem„ine pervâne-i dil belî dîvâne olur âteĢe ekser mâ‟il necâtî (k / ) güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer tasavvufi düĢünce sisteminde aĢk, sadece „beĢerî‟ varlığı kuĢatan bir kavram olarak değil, insanı olduğu kadar yaratıcı‟yı da ilgilendiren bir kavram olarak ele alınmıĢtır. zira mutasavvıflar varlık âleminin tecelli ediĢini, “ben, gizli bir hazine idim. bilinmemi istedim. halkı, bilinmem için yarattım…” (Ġsmail hakkı bursevî , ) kudsî hadisiyle açıklamıĢlar ve burada geçen “bilinmeyi isteme”yi de “aĢk” olarak yorumlamıĢlardır. bilinme, hüsn-i mutlak olan allah‟ın, kendi cemâline meylederek güzelliğini seyretmek için kâinatı bir ayna edinmesi suretiyle gerçekleĢir. yani allah‟ın kendi güzelliğini seyretmek istemesi, baĢka bir deyiĢle “aĢk”, kâinatın yaratılıĢ sebebini teĢkil etmektedir. ġem„ ve pervâne sembolizminde, aĢk kavramının allah‟la ilgili olan boyutu da “ateĢ” Ģeklinde karĢılık bulmaktadır. zira baĢında yanan ateĢ ve bu ateĢin sonucu olarak akıttığı gözyaĢlarıyla (mumun damla damla erimesi) mum, tam bir âĢık görünümündedir: „iĢk odı uğraĢdı Ģem„un cânına gör kim neçe gâh yanar geh gözlerinden ahıdur seyl-âblar nesîmî (g / ) bu aĢk, insanın allah‟a olan aĢkından önce gelmektedir. zaten Ģem„in, Ģem„ ve pervâne aĢkının öncelikli ve temel öğesi durumunda olması da bununla tam olarak örtüĢmektedir. dolayısıyla esas olan, öncelikli olan, allah‟ın “bilinme isteği”, baĢka bir deyiĢle “aĢk”ıdır. zira mevcudat yaratılmadan (allah‟ın aĢkı/Ģem„in yanması), allah‟ın bilinmesi (insanın aĢkı/pervânenin yanması) mümkün olmayacaktır. baĢka bir deyiĢle, mumun pervâneyi yakabilmesi için, öncelikle kendisinin yanması gerekmektedir: „aĢk odu evvel düĢer ma„Ģûka andan „âĢıka ġem„i gör kim yanmayınca yakmadı pervâneyi fuzûlî (cebecioğlu , ) “Ġlahî düzeyde, aĢka allah‟ın yaratıcı etkinliği denebilir” (chittick , ). bu etkinlik, ilahî kelâm olan “kün!” emriyle beraber ortaya çıkmıĢtır. zira “allah kur‟an‟da, „biz bir Ģeyi istediğimizde, ona tek sözümüz „ol!‟ demektir; o oluverir (nahl : ) de(mektedir). baĢka bir ifade ile âlemdeki her bir Ģey, allah‟ın kelâmının bir sonucu olarak vücuda gel(mektedir)” (chittick , ). allah‟ın ilminde var olmalarına rağmen, yokluğun karanlığı içinde kaybolmuĢ olan mevcudat, allah‟ın bu hitabıyla beraber ortaya çıkmıĢtır: cümle bir künden nümâyândır vücûd-ı kâ‟inât bâ‟is-i îcâd-ı kevn olan hitâb oldur ki ol ġeyh gâlib (g / ) ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer aĢk ve bunun sonucu olarak zuhur eden ilahî hitap, bütün kâinatın yaratılıĢına sebep olmuĢ ve böylece “gizli hazine/saklı güzellik”, görünür olmuĢtur: meger Ģem„-i tecellîdür cemâlün ki nûrından cihân oldu münevver nesîmî (g / ) tecellî tutdı âfâkı cemâlün Ģem„-i tâbından meger kim tal„atun ayı „ıyân oldı nikâbından nesîmî (g / ) açığa çıkmamıĢ, bilinmemiĢ, sevilmemiĢ bir güzellik ise yanmayan bir mum gibidir ki, bu da bütün mevcudatın yaratılmadan önce allah‟ın ilminde mevcut olmalarına tekabül etmektedir: “varoluĢun anlaĢılabilir baĢlangıcı yüce „nokta‟nın gizemindedir ve bu nokta, her Ģeyin baĢlangıcı olmasından dolayı, „düĢünce‟ (mahaşeba) olarak adlandırılmıĢtır. yaratıcı düĢüncenin gizemi, saklı „nokta‟ya tekabül eder” (guenon , ). Ġlahî hitapla beraber bu “saklı nokta” ortaya çıkmıĢ ve tüm âlemin merkezi durumuna gelmiĢtir: “nokta gerçekten birliğin sembolüdür. ancak onun ıĢımasıyla var olan (önceki „boĢluk‟ salt gizilgüçlülüktür, kuvve hâlidir) yayılımın ilkesidir. fakat ancak kendisinin de bu yayılımda onun merkezini oluĢturacak biçimde konumlanmasıyla kavranılabilir hâle gelir. (…) yayılıma gerçekliğini kazandıran, „boĢluğu bir Ģey hâline getiren ve olmayanı olur hâle getiren‟ ıĢığın neĢet ediĢi, konsantrasyonu izleyen bir südûrdur. (…) iĢık (aor), esirin (avir) gizeminden fıĢkırır. saklı nokta yani „yod‟ harfi tezahür eder. (…) Ġlâhiyat diliyle, tanrı‟nın kelâmı ile kendini „Âlemin merkezi‟ kılması söz konusudur” (guenon , ). dolayısıyla yaydığı ıĢığın ortasında bulunan “Ģem„/mum”, tüm tezahürün kaynağı olan merkezî noktayı sembolize etmektedir. yaratılıĢ, aynı zamanda “vahdet/birlik (yanak, boy)”in, “kesret/çokluk (hat, perçem)”a dönüĢmesi anlamına gelmektedir: haddün hayâli gitdi vü geldi hatun dile yandugı yirde kor dütünin yâdigâr Ģem„ mesîhî (g / ) kâmetün bir Ģem„dür ruhsârun anun Ģu„lesi ger o Ģem„ün dûdidur dirsem revâdur perçemün zâtî (g / ) klasik türk edebiyatında “yüz(birlik)”den zuhura gelmesi ve onu örtmesi bakımından madde âlemini sembolize eden “hat” ve “perçem”, mumun alevinden çıkan dumanla renk (siyah) bakımından ortaktır. siyah renk ise ölümün, „asl‟a dönüĢün rengi olması güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bakımından, madde âleminin asli bir varlığa sahip olmadığına göndermede bulunur bir mahiyet taĢımaktadır. nitekim madde âlemi, her an “varlık”la “yokluk/ölüm” arasında bir gidiĢ geliĢ hâlindedir. yok olarak “asl”ına döndükten sonra tekrar var olur; ama eskinin aynı olarak değil, değiĢime uğramıĢ bir Ģekli olarak var olur. dolayısıyla da madde âlemi, her an ölümü yaĢamaktadır ve siyah da bu durumu ifade etmek için kullanılan sembolik bir renktir. yukarıda da bahsetmiĢ olduğumuz gibi aĢk, allah‟ın “bilinme isteği”dir. “aĢk” ve “bil(in)mek” fiilinin sonucu olarak ortaya çıkan “bilgi”nin ortak noktasını ise her ikisinin de ortaya çıkabilmesi için “âĢık-maĢuk” ve “bilen-bilinen” olmak üzere “iki” unsura ihtiyaç duyulması gerekliliği oluĢturmaktadır. ahmed gazzâlî, bu gerekliliği Ģu sözlerle açık bir Ģekilde ifade etmektedir: “hüsnün gözü kendi cemâline kapalıdır; öyle ki âĢığın aĢk aynası olmadıkça kendi güzelliğinin mükemmelliğini temâĢâ edemez. ĠĢte bu yüzden, cemâl için bir âĢık gerekir, tâ ki mâĢuk, aĢk aynasında kendini görebilsin ve âĢığın talebinden nasibini alabilsin” ( , ). hem “aĢk” hem de “bilgi”nin ortaya çıkabilmesi için gerekli olan iki unsurdan her biri, eĢit derece önemli ve gerekli durumdadır. zira bu unsurlardan birinin yokluğu, aĢk ve bilgiden bahsetmeyi imkân dıĢı bırakmaktadır. ĠĢte “Ģem„/allah” ve “pervâne/sâlik”, hem “aĢk” hem de “bilgi” için gerekli olan “ikilik”i meydana getirmektedirler ve söz konusu bu ikilik, allah‟ın yaratma iradesinin bir sonucu olarak ortaya çıkmıĢtır. o‟ndan baĢka bir varlık olmadığı için de söz konusu “ikilik”, itibari bir durumdur: “Öte yandan, iki öğe arasındaki iliĢki bir bilgi iliĢkisi olarak da tasavvur edilebilir. bu durumda, varlık kendisini tanımak (bilmek) için, deyim yerindeyse, kendisini kendisinin karĢısına koyarak özne ve nesne oluĢturacak biçimde ikiye bölünür. fakat burada da yine bu ikisi gerçekte birdir. bu husus, özne ile nesne özdeĢleĢmesini gerektiren, tüm gerçek bilgiler için geçerlidir. bu durum, bilginin var oluĢu ölçüsünde, „bilen varlık bilinen varlıktır‟ biçiminde ifade edilebilir” (guenon , ). bütün bunlardan da anlaĢıldığı gibi, “Ģem„ ve pervâne” sembolizmi, aĢkı, yaratıcı‟dan baĢlayarak anlatmaktadır. zira Ģem„/mum önce kendi yanmakta, daha sonra ise ateĢiyle pervâneyi yakmaktadır. aĢkın, yaratıcı‟yla ilgili olan boyutu, varlık halkasını oluĢturan yaylardan “kavs-i nüzûl”a tekabül etmektedir. “bilgenin Ġlke ile sırra ulaĢmak için kat ettiği yol (ise) bu evrelerden ikincisidir. yani baĢlangıca dönüĢ hareketidir” (guenon , ). dolayısıyla da bu halkanın ilk yayını mumun yanıĢı oluĢtururken ikinci yayını ise pervânenin yanıĢı (kavs-i urûc) oluĢturacaktır. “zira yere inmek, aĢk ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer iptilâsı içindir” (Ġsmail hakkı bursevî , ). böylece, yaratıcı‟nın bilinmeye duyduğu aĢkla açılan varlık halkası, pervânenin mumun ateĢinde yanmasıyla beraber kapanacak, baĢka bir deyiĢle tamamlanacaktır. zira yanan bir mumun olduğu yerde, onun ateĢinde yanacak olan bir pervâne de mutlaka olacaktır: tal„atın Ģem„i durur ġeyhî‟yi odlara yakan ta„n mı pervâne yakılsa nerede kim ola mum ġeyhî (g / ) mum; “beyaz” bedeni, “kırmızı” alevi ve “siyah” dumanıyla da yaratılıĢı ifade etme hususunda sembolik bir değere sahiptir. zira söz konusu renkler, tasavvufi düĢünce sisteminde, tedrici bir Ģekilde gerçekleĢen tecellinin çeĢitli aĢamalarını sembolik olarak ifade etmek için kullanılmaktadır. mum, dumanının yanı sıra, geceleri yanması bakımından da gecenin rengi olan “siyah”la yakından ilgilidir. onun karanlığın içinde yanması, yanması neticesinde ortaya çıkan dumanın siyahlığından daha önceliklidir. zira gece, yani siyah Ģem„ ve pervâne arasındaki karĢılıklı iliĢkinin baĢlamasından önceki aĢamaya tekabül etmektedir. mumun yanması, sembolik olarak yaratılıĢı ifade ettiğine göre; gece, yaratmanın henüz gerçekleĢmemiĢ olmasına iĢaret etmektedir. zira mutasavvıfların da çoğu zaman “„adem/yokluk” ve “siyah/gece” arasında bir ilgi kurma eğiliminde oldukları görülmektedir. bunun en büyük sebebini ise siyahın bütün renkleri yutması -gece söz konusu olduğunda ise karanlığın, bütün varlıkların üzerini örterek görülmelerini engellemesi, baĢka bir deyiĢle onları bir nevi “yok” etmesi- oluĢturmaktadır: “siyah ise yutan bir renktir. bütün renkler onun içinde yok olup gider. siyah tamamen bir renksizliktir. onun için mutasavvıflar allah‟ın yaratma iradesinden önceki mertebeyi yani „zât-ı ahadiyyet‟i, tecellisizlik ve mutlak anlamda idrak edilemezlik yönlerinden dolayı siyahla simgelemiĢlerdir” (yıldırım , ). mumun bedeninin rengi olan “beyaz” ise içinde bütün renkleri barındıran bir renktir. dolayısıyla da o, bütün renklerin kaynağı olan renktir. bu da beyazı, allah‟ın “yaratma iradesi”nin sembolik ifadesi olarak kullanmak için yeterli bir gerekçe teĢkil etmiĢtir: “renk üzerine çalıĢan uzmanlar, aslında bütün renklerin, ıĢığın yani beyazın farklı yansımaları olduğunu tespit etmiĢlerdir. beyaz görünen güneĢ ıĢığına prizmayı tuttuğumuzda diğer renkleri gözlemlememiz mümkün olmaktadır. bu durum, tasavvuf ehlinin, her Ģeyin aslını mutlak nur‟a dayandırması anlayıĢını tam olarak simgelemektedir. nihayetinde „bin bir‟ olarak adlandırdığımız renklerin kaynağı beyaz renktir. bu, aynı zamanda vahdet-kesret güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer meselesini de aydınlatmaktadır; zira bu kadar çokluk, aslında bir‟in tecelli ve tezahüründen baĢka bir Ģey değildir” (yıldırım , ). alevin rengi olan “kırmızı” ise bütün canlılığıyla, yaratma eyleminin öncesindeki “bî-rengî (renksizlik)” hâlinin yaratılıĢ neticesinde “çeĢitlilik”e dönüĢmüĢ olmasına iĢaret etmekte ve bu nedenle de madde âlemini temsil etmektedir. buna sebep ise onun, -siyah ve beyazın dıĢında- bütün renkleri temsil ediyor oluĢudur: “kırmızı, renklerin içinde en kesif ve dikkat çekici olanıdır. bu itibarla aslında siyah ve beyazın dıĢındaki bütün renkleri temsil etmektedir. bir diğer söyleyiĢle tamamen varlık âlemini simgeler. zira görünen tarafı ile varlık âlemi rengârenktir” (yıldırım , ). bu noktada, alevin sadece rengi bakımından değil, “kendisi” olarak da madde âlemini sembolize etmede önemli bir sembolik değer olma niteliğini taĢıdığını belirtmemiz gerekmektedir. zira bachelard, “ateĢ, her Ģeyi açıklayabilecek ayrıcalıklı bir olgudur. eğer yavaĢ değiĢen her Ģey yaĢamla açıklanabilirse, hızlı değiĢen her Ģey ateĢle açıklanabilir. ateĢ, en ileri düzeyde canlı öğedir.” ( , ) derken varlık âleminin niteliklerinden bahsediyor gibidir. sürekli olarak titreyen, yenilenen ateĢ, bu özelliğiyle tam olarak madde âlemini karĢılar durumdadır. zira tasavvufi düĢünce sistemine göre de yaratma, “geçmiĢ”e ait olan ve onunla sınırlanan bir eylem değil; geçmiĢi, Ģimdiyi ve geleceği içine alan bir eylemdir. dolayısıyla da yaratılıĢ, “statik” değil, “dinamik” bir karaktere sahiptir. mutasavvıflar, “o, her gün (her an) bir iĢtedir” (kur‟ân rahmân, ) âyetini buna delil olarak göstermiĢlerdir. mumun dumanı ise yukarıda da ifade etmiĢ olduğumuz gibi, yine renk sembolizmi bakımından (siyahın matemin, “asl”a dönüĢün rengi olması) madde âleminin, “yokluk”un içinden var olduktan sonra, tekrar “yokluk”a dönüyor veya dönecek olmasını temsil eder durumdadır. ġeyh gâlib, bir beytinde siyah, beyaz ve kırmızıyı birbirini bütünleyici öğeler (allah‟ın zâtı, yaratma iradesi ve varlık âlemi) olarak kullanmakta ve bu suretle de mumun, ancak yandığında vasfını tamamlayacağını (yıldırım , ) ifade etmiĢ olmaktadır: bu dûd u Ģu„le vü ten-i kâfûr-fâm ile ġem„ eyler âh u zâr sefîd ü siyâh u sürh ġeyh gâlib (g / ) “pervâne mumun etrafında dönen kelebektir. ateĢin cazibesine kapılıp neticede yanarak yok olmaktadır. (…) pervânenin bir diğer anlamı ise haberci, yani peygamber demektir” (yıldırım , - ) ki söz konusu kelimenin bu anlamı, yaratılıĢla ilgili ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer önemli bir gerçeğe iĢaret etmektedir. zira allah‟ın, “sen olmasaydın felekleri yaratmazdım” Ģeklindeki hitabına mazhar olan “hz. peygamber, gerçeklik kazanmıĢ aĢkın kemâlidir; âlem onunla ve onun yüzü suyu hürmetine yaratılmıĢtır” (chittick , ): rahmeten li‟l-„âlemîn sen seyyid-i kevneyn hem ġem„-i ruh-sârundan oldı kün fekân gark-ı zıyâ nesîmî (g / ) “mutasavvıflar, devir nazariyesini hz. peygamber‟in „ben nebi iken Âdem su ile çamur arasındaydı‟ hadisine isnad ederler. buna göre ilk yaratılan nur, hz. peygamber‟in nurudur” (yıldırım , ). bu nedenle de “Ģair, peygamber haberdar değilken ben haberdardım, diyerek vahdeti hatırlatır” (yıldırım , ): Âhum göge boyandı göge gök boyanmadın yandum o Ģem„ Ģevkıne pervâne yanmadın bâkî (g / ) yaratmanın ardından mum (merkezî nokta), bütün varlık âlemi için bir cazibe merkezi hâline gelmiĢtir. bu cazibeye kapılmıĢ olan varlık âlemi, mumun etrafında dönen pervâne gibi, merkezî noktanın etrafında sürekli olarak dönüp durmaya baĢlamıĢtır: yedi Ģem„in iĢi pervâneliktir yanalıdan beri hüsnün çerâğı ġeyhî (g / ) yüzün bedri cihânun dânesidür yir ü gök ayla gün pervânesidür nesîmî (g / ) bu dönüĢ, varlık âleminin yaratılmasına sebep olan ve bu nedenle de bütün varlık âlemini kuĢatmıĢ olan “aĢk”ın sebep olduğu ĢaĢkınlığın bir sonucu olarak ortaya çıkmaktadır: „Âlemi pervâne-i Ģem„-i cemâlin kıldı „aĢk cân-ı „âlemsin fidâ her lâhza bin cândır sana fuzûlî (g / ) cezbe-i nûr-ı mahabbetdir medâr-ı kâ‟inât anlamaz bu sırrı bir Ģeb olmayan mihmân-ı „aĢk ġeyh gâlib (tr / ) bütün varlık âlemi için söz konusu olan bu “dönüĢ”, koptuğu “bütün”le tekrar birleĢme arzusunun bir tezahürü durumundadır. zira “her varlık, kendi menĢeine dönmek ve kaybettiği mükemmelliği bulmak hususunda içinde bir istek duyar. bu istek aĢk dediğimiz Ģeydir. ġu halde aĢkın gâyesi „eksiğini tamamlamak‟tır” güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer (güngör , ). dolayısıyla da bütün kâinatı kuĢatmıĢ olan “dönmek” eylemi, “asl”a “dönme” istek ve çabasının bir tezahürüdür. nitekim “dönmek” fiili, “kendi ekseni üzerinde veya baĢka bir Ģeyin dolayında hareket etmek” anlamının yanında, “geri gelmek, geri gitmek” anlamına da gelmektedir. varlık âleminin dönüĢüyle ilgili olarak düĢünüldüğü zaman söz konusu kelimenin ikinci anlamı, ilk anlamını içerir durumdadır. zira devir nazariyesine göre, varlığın “kopmuĢ” olduğu “bütün”e tekrar ulaĢabilmesi için, “kavs-i nüzûl” ve “kavs-i urûc” olmak üzere karĢılıklı iki yayın meydana getirdiği çemberi tamamlaması, baĢka bir ifadeyle onun üzerinde bir tur “dönme”si gerekmektedir. varlık âlemi, aĢkın sebep olduğu sarhoĢluk ve koptuğu “bütün”e geri dönme arzusuyla Ģuursuz bir Ģekilde dönüp dururken bütün kâinata Ģâmil olan bu “dönme” eylemine bir bilincin sayesinde/sonucunda katılan tek varlık ise insandır. zira insan, ancak bu bilinç sayesinde taĢıdığı potansiyelin (eĢref-i mahlûkât olma) Ģuuruna varacak ve bu potansiyeli açığa çıkarma yolunda harekete geçecektir. yukarıda da bahsetmiĢ olduğumuz gibi yaratılıĢ (baĢka bir ifadeyle, mumun yanması), varlık halkasını meydana getiren yaylardan ilki olan “kavs-i nüzûl”a tekabül etmektedir ve yaratılıĢ neticesinde insan, “asl”ından koparak “dip nokta” durumunda olan dünyaya “inmiĢ/düĢmüĢ”tür. bunun sebebi ise allah‟ın “bilinme isteği”, baĢka bir ifadeyle “aĢk-ı zâtî”dir. ancak aĢk, “asl”dan kopmaya sebep olduğu gibi, o‟na tekrar ulaĢmanın da vasıtası durumundadır. fakat yaratmaya, baĢka bir deyiĢle “asl”dan kopmaya sebep olan aĢk, allah‟ın “bilinme isteği (aĢk-ı zâtî)” iken o‟nunla tekrar bütünleĢmeyi sağlayacak olan aĢk ise insanın allah‟a olan aĢkıdır. bununla beraber, ilahî aĢk beĢeri/mecazi aĢktan oldukça farklı bir özellik arz etmektedir. azîzüddîn nesefî ve ahmed gazzâlî, bu farkı çok açık bir Ģekilde ortaya koyarlar. beĢeri aĢkı, “aĢk bir âteĢtir. ÂĢıka düĢer ve bu âteĢin mevzi„i gönüldür ve bu âteĢ göz yoluyla gönle gelir ve gönülde tavattun eder” (azîzüddîn nesefî , ) Ģeklinde ifade eden azîzüddîn nesefî‟nin sözlerinden de anlaĢıldığı gibi beĢeri aĢk, göz yoluyla gönle giren, yani dıĢarıdan içeriye (gönle) giren bir aĢktır. Ġlahî aĢkın ortaya çıkıĢ biçimi ise beĢeri aĢkın ortaya çıkıĢ biçiminden oldukça farklıdır. Çünkü ilahî aĢk, ruhların elest meclisinde allah ile yaĢadıkları vuslat sırasında baĢlamıĢtır. bu nedenle de ilahî aĢk, beĢeri aĢk gibi dıĢarıdan içeriye giren bir aĢk değil, içeriden dıĢarıya çıkan bir aĢktır. ahmed gazzâlî ilahî aĢkla ilgili bu hususu, Ģu sözlerle ifade etmektedir: “aĢkın sarayı cân eyvanıdır. ‘ben sizin rabbiniz değil miyim?’ (a„râf: / ) mührü ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer rûhlara ezelde vurulmuĢtur. orada bir yük yükletilmiĢtir. eğer perdeler ĢeffaflaĢırsa aĢk da örtülerin altından parlayıverir. burada büyük bir sır vardır; yani sözü edilen bu aĢk, içeriden dıĢarı çıkar” ( , ). dolayısıyla da insan, bu çokluk âlemine inerken/düĢerken allah‟a tekrar kavuĢmasını sağlayacak olan aĢkı da beraberinde getirmiĢtir: dedim rûz-ı ezel oldum bu bezm-i hüsne pervâne gülüp dedi ki gelmedi bu bezme kimse senden geç necâtî (g / ) merkezden uzaklaĢ(tırıl)mıĢ olmak ve tekrar oraya yönelmek ve ulaĢmak, varlık halkasının birbirini takip eden iki aĢamasını meydana getirmekte ve bunlardan birinin (kavs-i nüzûl) sonu, diğerinin (kavs-i urûc) baĢlangıcı olmaktadır. ancak söz konusu iki aĢamanın arasında yer alan ve “devr”i -geçici bir süreliğine de olsa- kesintiye uğratan “gaflet/unutma” hâli de kaçınılmaz olması bakımından varlık halkasına dâhil olmaktadır. Çünkü dünyaya “iniĢ/düĢüĢ”le beraber insan, bezm-i elestte allah‟a vermiĢ olduğu sözden ve o‟na olan aĢkından “gâfil” olmakta, baĢka bir deyiĢle bunları unutmaktadır: “o varlıklar (ruhlar), bu karanlık bedene kendilerini bağımlı hissedince, arzularının kendilerini yönelttiği Ģeylere koĢtular ve ancak kendi tabiatlarına uygun olanı sevdiler. kendilerini yaratan allah‟ın rablığı üzerine yaptıkları Ģahitlikten gâfil oldular” (Ġbn arabî , ). ancak söz konusu aĢkın unutulmuĢ olması, onun yok olduğu anlamına gelmemektedir. dolayısıyla da insan unutmuĢ olmasına rağmen, hâlâ bu aĢkı potansiyel olarak kendisinde taĢımaktadır. söz konusu bu aĢkın potansiyel olmaktan çıkıp tezahür edebilmesi için, sadece bu “unutkanlık” durumunun ortadan kalkması gerekmektedir. bu nedenle de insanın allah‟a tekrar kavuĢmak için gösterdiği veya göstereceği çabanın/hareketin baĢlangıcı olacak Ģey, bir “hatırlama”dan ibarettir. bu noktada ateĢ, “hatırlatıcı” bir unsur olarak devreye girerek insana, yitirdiği birlik‟i hatırlatacak ve “yok olmak” suretiyle, ayrıldığı bütün‟e tekrar kavuĢma arzusu uyandıracaktır. zira “insana geliĢmeye açık bir derinliğin dersini ver(en)” (bachelard , ) ateĢ, insanda “değiĢtirme, zamanı hızlandırma ve yaĢamı sonucuna ulaĢtırma isteği uyandırır. bu koĢullarda düĢleme gerçekten büyüleyici ve çarpıcı olur. Ġnsan yazgısını açıp geniĢletir; küçük olanı büyüğe, ocağı volkana, bir kütüğün yaĢamını dünyanın yaĢamına bağlar. büyülenmiĢ kiĢi cenaze töreni ateşi’nin çağrısını duyar. böyle bir kiĢi için yok oluĢ bir değiĢimden öte bir Ģeydir, bir yenilenmedir” (bachelard , ). güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer pervâne, önce karanlığın içindedir ve onun bu hâli, “gaflet” durumuna denk gelir. ancak daha sonra, uzaktan mumun alevini görür ve onun cazibesine kapılarak muma yaklaĢmaya baĢlar. dolayısıyla “uyanıĢ/farkındalık/alevin çağrısı”, muma/sevgiliye yönelme konusunda baĢlangıç noktası olur. yöneliĢin sebebini ise muma/allah‟a kavuĢma isteği oluĢturmaktadır. zira her eylem, bir amaca hizmet eder. baĢka bir deyiĢle insan/pervâne, muma/sevgili‟ye kavuĢma arzusunu gerçekleĢtirmek için harekete geçmiĢtir artık ve bu hareket, ancak bir farkındalığa ulaĢmanın sonucu olarak baĢlamıĢtır: ruhlarına sünbülünden meyl eder bu murg-ı dil görse Ģem„i geceler pervâneler pervâz eder ahmet paĢa (g / ) mum, aleviyle pervâneyi kendisine doğru çeker ve ona, yönelmesi gereken yönü gösterir. bu yön, merkeze doğrudur, merkezi/mumu iĢaret eder. dolayısıyla da bu aĢamada alev, pervâne için gideceği yolu gösteren bir “kılavuz” olma fonksiyonunu yüklenmiĢ durumdadır. “mumun alevindeki dikeylik, pervânenin ruhunda da yükselme hissini uyandırmıĢ; bu his, onun ilahî olana daha fazla yaklaĢmasına vesile olmuĢtur. pervâne, mumun kılavuzluğunda, yönünün çemberden merkeze; yani ilahî olan (gökyüzü)a doğru olması gerektiğini öğrenecektir” (demirel , ): rûĢen et çeĢm-i çerâğı cân u dil bulsun safâ zulmet içre kalmasın pervâne allah aĢkına ġeyh gâlib (g / ) ġem„-i ruhudur „aĢk tarîkinde delîlim gönlüm Ģeb-i zülfünde bulursa n‟ola râhı ahmet paĢa (g / ) zülfi Ģebinde yolunı yanılma ey gönül ruhsâr-ı dost çünki elinde dutar Ģem„ mesîhî (g / ) gerçi zulmete saçun dâldür iy fitne delîl „ÂĢıka Ģem„-i ruhun nûrını reh-ber didiler nesîmî (g / ) alevin çağrısı, hareketin baĢlangıcıdır ve bu çağrı, sevgili‟nin çağrısıdır aslında. zira “tasavvufta insan hem arayan, hem aranılandır; yani allah da onu sever ve arar” (güngör , ). dolayısıyla insanın allah‟a olan aĢkı tek taraflı değil, karĢılıklı bir aĢktır. baĢka bir deyiĢle aĢk, insanla olduğu kadar yaratıcı‟yla da ilgili olan bir ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer kavramdır. Çünkü pervâneyi/ sâliki yakan ateĢin/ aĢkın, mumu/sevgili‟yi yakmaması mümkün görünmemektedir: sûz-ı dilden bî-haberdür sanmanuz cânâneyi ġem„i yakmaz mı ol âteĢ kim yakar pervâneyi ġeyhülislâm yahyâ (g / ) ancak bu noktada, allah‟tan insana yönelen aĢkın mı yoksa insandan allah‟a yönelen aĢkın mı öncelikli olduğu sorusunun net bir cevabı verilememektedir. baĢka bir deyiĢle, hangi tarafın aĢkının öncelikli olduğu kesin değildir; ancak kesin olan bir Ģey vardır ki aĢk, bir tarafta ortaya çıkıp sağlam olursa diğer tarafta da kaçınılmaz olarak ortaya çıkacaktır: “aĢk bir bağlılık râbıtasıdır, her iki tarafla da alakası vardır. eğer bu râbıta âĢık tarafında sağlam olursa bağlılık her iki tarafta da zorunlu olarak ortaya çıkar ki bizzat bu durum birliğe giriĢtir” (ahmed gazzâlî , ). dolayısıyla da insan ve allah arasındaki aĢk, birbirini tetikleyen bir nitelik arz etmektedir. baĢka bir deyiĢle, herhangi bir tarafta ortaya çıkmakta ve zincirleme bir Ģekilde geliĢmektedir: yanarlar âteĢine âkıbet biri birinin mizâc-ı Ģu„le tenük germ ü zûd pervâne nâilî (g / ) müselseldir kanâdîl-i mahabbet biribirini eyler nûra meĢhûn ġeyh gâlib (tr / ) “ġem„ ve pervâne” sembolizminde ise mumun pervâneyi yakabilmesi için öncelikle kendisinin yanması gerektiğinin vurgulanıyor olması, söz konusu sembolizmde, allah‟ın kuluna olan aĢkının ön planda olduğu Ģeklinde bir değerlendirme yapmaya imkân ahmed gazzâlî, bu belirsizliği açıkça ortaya koyar. ama kendi görüĢü, daha ziyade allah‟ın kuluna olan aĢkının öncelikli olduğu yönündedir: “aslında aĢk iki gönül arasındaki yakınlıktır. ama âĢığın mâĢuka aĢkı baĢka, mâĢukun âĢığa aĢkı daha baĢka bir Ģeydir. ÂĢığın aĢkı gerçektir; mâĢukun aĢkı ise âĢığın aĢkının mâĢukun aynasındaki yansımasıdır. müĢâhedede karĢılıklı bir iliĢki söz konusu olduğundan, âĢığın aĢkı her durumda çaresizlik, zillet, ezilmiĢlik, hakirlik ve teslimiyeti gerektirir. mâĢukun aĢkı ise tahakküm, kibirlenme ve büyüklenmeyi. (…) ama âĢık hangisi, mâĢuk hangisi? bilmiyorum. bu en büyük sırdır. zira, önce sevgilinin cezbetmesi, derken âĢığın iĢi tamamlaması söz konusu olabilir. bu dünyada ise durum tersinedir. „allah irade etmedikçe siz edemezsiniz.‟ (Ġnsan: / ; tekvir: / ) ġüphesiz, „o onları sever‟, „onlar o’nu sever‟den önce gelir. bâyezid (r.a.) Ģöyle demiĢtir: „uzun süredir, benim o‟nu istediğim yanılsaması içindeydim, ama beni isteyen önce kendisiymiĢ‟ ” ( , - ). güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer vermektedir. dolayısıyla da söz konusu sembolizmde aĢk, insandan allah‟a yönelmiĢ olduğu gibi, allah‟tan da insana yönelmiĢ durumdadır ve bunlardan ikincisi, ilkinin sebebini teĢkil etmektedir. yani öncelikli olan, allah‟ın kuluna olan aĢkıdır; ama bunun yanında kulun allah‟a olan aĢkı da söz konusudur. dolayısıyla da “Ģem„ ve pervâne” sembolizminde her iki aĢk, birlikte iĢlenmektedir. allah ve insan arasındaki aĢkın, sadece bir tarafı ilgilendiren bir durum olmadığı hususu, tasavvufi sembolizmde “ip” sembolüyle de iĢlenmiĢtir. zira “ip” de tıpkı aĢk gibi, “iki” unsurun varlığına -zira ip, iki uçludur- ve karĢılıklı bir bağlılığa iĢaret etmektedir. ġems-i tebrizî bu hususu, “o bana bir ipin ucunu verdi. bana ‘çek ki ben de çekebileyim. ancak çekerken koparma’ dedi.” (livingston , ) Ģeklinde, hâfız ise “Ġpin sendeki ucunu iyi muhafaza et ki, o da kendisindeki ucu iyi muhafaza edebilsin.” (livingston , ) Ģeklinde ifade etmiĢtir. aĢkın, sadece “beĢerî” varlığı kuĢatan bir kavram olmayıp insanı olduğu kadar yaratıcı‟yı da ilgilendiriyor olması, tasavvufi düĢünce sisteminde oldukça önemli bir yer iĢgal eden bir kabulle de çok yakından ilgilidir. bu düĢünceye göre ruh, ilahî bir nefha olması nedeniyle, ilahî kaynaklıdır. bu da allah ve insan arasında “ontolojik bir birlik” olduğu düĢüncesini ortaya çıkarır ve “allah ile insan arasında bir mâhiyet ortaklığının mevcudiyeti, tasavvufun âdeta temelini teĢkil eder. sûfîler en azından insan rûhunun bütün diğer yaratılmıĢlardan farklı olduğunu, rûhun allah ile aynı Ģey olmasa bile ondan bir Ģey olduğunu kabul ederler” (güngör , ). dolayısıyla da allah‟ın varlığı bir ateĢse insan da bu ateĢten sıçramıĢ/kopmuĢ olan bir kıvılcımdan baĢka bir Ģey değildir: olaydı muktebes-i hüsn-i dil-fürûzun Ģem„ ederdi her Ģererinden zuhûr pervâne nâilî (g / ) “ „ġem„‟ kelimesi, „balmumu, çerağ, kandil, aydınlanmak için yakılan her Ģey, yıldızlar‟ ve „payanda‟ anlamlarında kullanılmaktadır” (kanar , ). “pervâne” kelimesi ise genel olarak, “çerâğa âĢık olan ve geceleri kendini mum alevine atan böcek” anlamında kullanılmakla beraber, aslında “yıldız” anlamına gelen ve mutasavvıflar bu konuda, “ona Ģekil verdiğim ve ona rûhumdan üflediğim zaman, siz hemen onun için secdeye kapanın!” (kur‟ân, hicr: ) âyetini delil olarak göstermektedirler. ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer mecazen “çerâğ” ve “mum ıĢığı” yerine kullanılan “perv” ile nisbet bildiren “-âne” son ekinin birleĢmesiyle meydana gelmiĢtir (kanar , ). dolayısıyla da klasik türk edebiyatında âĢık ve maĢuğu temsil eden “pervâne” ve “Ģem„ ” kelimeleri arasında bir bakıma “anlamsal bir birlik” söz konusudur ki bu durum, yukarıda bahsetmiĢ olduğumuz ve allah‟la insan arasında var olduğu kabul edilen “ontolojik birlik” konusuyla yakından ilgilidir. dolayısıyla mumun alevinde yanan pervâne, bir bakıma kendini feda ettiği Ģeyle (ateĢ) “aynı”dır. bu durum, pervânenin/insanın mum/allah hakkında bilgi sahibi olabilmesi gereklidir de. nitekim “tanrı‟nın varlığına karıĢarak birlik hâlini yaĢamak, birbirine karıĢan ve bir olan iki Ģeyin aynı cevherden olmasını gerektirir. gerçekten, insanın tanrı‟yı bilmesi kendisinde „ilahî‟ bir parçanın bulunmasından dolayıdır” (güngör , ): sendedür leylî niçün mecnûn olup dîvânesen ġem„ bigi hâ yanarsan ne „aceb pervânesen nesîmî (g / ) “ġem„ ” ve “pervâne” kelimeleri arasındaki söz konusu yakınlığa bağlı olarak pervânenin muma doğru yöneliĢi, “asl”a duyulan özlemin ve tekrar ona ulaĢma arzusunun bir tezahürü durumundadır. dolayısıyla da kendisinde “ilahî bir öz” taĢıyan; ancak dünyaya inme/düĢme neticesinde allah‟tan ayrılmıĢ olan insanın o‟nunla tekrar bütünleĢme gayesini, baĢka bir deyiĢle menĢeine geri dönme isteğini yansıtmaktadır. bu yöneliĢi sağlayan Ģey ise daha önce de ifade etmiĢ olduğumuz gibi, alevin/sevgili‟nin çağrısıdır. bununla beraber, aslında sevgili‟nin çağrısı da insan ve yaratıcı arasında var olduğu kabul edilen “ontolojik birlik”in bir sonucu olarak ortaya çıkmaktadır. zira yaratma neticesinde ortaya çıkan “ayrılık”, allah ile insanın değil, allah ve o‟ndan uzak düĢmüĢ olan ruhun ayrılığıdır. bu ayrılığın insana aitmiĢ gibi görünmesi ise ilahî nefhayı taĢımasından kaynaklanmaktadır. “asl”ından ayrılan ilahî nefhayı taĢıdığı için de ayrılıktan kaynaklanan “özlem” ve buna bağlı olarak da koptuğu bütün‟e tekrar kavuĢma arzusu, pervânede/insanda ortaya çıkmaktadır. ancak bu özlem, sadece bütün‟den ayrılan ilahî nefhayı kendisinde taĢıyan insana değil, ayrılığın taraflarından biri olan allah‟a da ait bir husustur. ancak “hak, özlem sahibi olan kula değil, ancak, kulun aynında görünen kendi nefsine ve kul mazharında nefh edilmiĢ olan kendi ruhuna özlem duy(maktadır)” (sunar , ). bu ise allah‟tan kula yönelen aĢkın temelini teĢkil etmektedir. bu noktada Ģöyle bir soru akla gelmektedir: aĢk, seven ve sevilen için ortak bir paydaysa allah ve insan arasındaki aĢkta insanın güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer “âĢık”, allah‟ın ise “maĢuk” olarak konumlandırılmıĢ olmasını belirleyen etken ne olmaktadır? bu, aslında beĢerî aĢk iliĢkileri için de geçerli olan bir sorudur ve söz konusu soruya ilk etapta Ģöyle bir cevap vermek mümkündür: her iki tarafın da pay sahibi olduğu aĢkın yaĢanma sürecinde, söz konusu taraflardan biri, bu olguya daha fazla katılmaktadır. baĢka bir deyiĢle aĢk, seven ve sevilen için ortak nokta olmakla beraber, tarafların her ikisinde de eĢit derecede ortaya çıkmamaktadır. bu da aĢkın fâili (âĢık) ve aĢkın nesnesi (maĢuk) Ģeklinde bir tanımlama yapmaya yol açmakta ve böyle bir tanımlama da fâil/âĢık konumunda olan kiĢinin aĢktan daha fazla pay almıĢ olduğu anlamını barındırmaktadır. allah ve insan arasındaki aĢkta, kulun allah‟a olan aĢkının “bütün”e yönelik, allah‟ın insana olan aĢkının ise “parça”ya yönelik olduğu göz önünde bulundurulduğu zaman, bu aĢkta hangi tarafın aĢk olgusuna daha fazla katılabileceği, dolayısıyla hangi tarafın “âĢık” hangi tarafın ise “maĢuk” tanımlamasına daha yakın olduğu kendiliğinden ortaya çıkmaktadır. “ÂĢık” ve “maĢuk” sıfatlarının aĢkın tarafları arasında nasıl ya da ne kadar paylaĢılacağını belirleyen bir diğer etken ise “eylem/eylemsizlik”tir. aĢk hususunda eylem, arzu nesnesine yakın olma ve ona ulaĢma yolunda harcanan çabayı ifade etmektedir. bu durumda aĢktan daha fazla pay alan tarafın “eylem” hâlinde olacağı kesindir. dolayısıyla da aĢkta “etkin” olan taraf “âĢık”, “edilgen” olan taraf ise “maĢuk” konumunda olacaktır. “ġem„ ve pervâne” arasındaki aĢkta “eylemsiz” olan taraf, “ayağı yere yapıĢık” olmasından dolayı klasik türk Ģiirinde çoğu zaman “ayağı bağlı” olarak nitelenen “Ģem„/mum”dur. onun tek eylemi, alevinin cazibesi sayesinde pervâneyi kendine doğru çekmektir -baĢka bir ifadeyle, “çağrı”- ki aslında, bu bir eylem bile değildir. zira “çekmek”, her ne kadar bir eylemse de “cazibe”yi ifade ettiği zaman bir “eylem” olmaktan çıkmakta ve güzelliğin doğal bir sonucu durumuna gelmektedir. yani pervâneyi kendisine doğru çekmek, onun bir eyleminin değil, sahip olduğu “cazibe”nin bir sonucudur. dolayısıyla da mum, “bir anlamda bir duygusal iliĢkinin hareketsiz baĢlatıcısıdır; aĢk uyandırır, aĢkın yöneldiği hedef iĢlevi görür” (andrews , ) ancak o, “iliĢkiye doğası gereği katılamaz” (andrews , ). zira onun “ayağı bağlı”dır ve bu da onu, doğal olarak “eylemsiz” olan taraf durumuna getirmektedir. o‟nun eylemi, âĢığı eylem hâline geçirmektir. o‟na yakın olmak ise “eylem” gerektirir ki söz konusu eylem, pervâneye aittir. “pervâne”nin hareketi ve “Ģem„(mum)”in hareketsizliği, bu iki unsur arasındaki aĢkta pervâneyi “âĢık”, Ģem„i ise “maĢuk” konumuna getirmektedir. ġem„in cazibesi pervânede “eylem”e ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer dönüĢmekte ve bundan sonra da söz konusu bu aĢk iliĢkisinde pervâne “etkin” Ģem„ ise “edilgen” olmayı sürdürmektedir. ancak “Ģem„ ve pervâne” aĢkının ilahî aĢkı sembolize ettiği hatırlandığı zaman, görünüĢteki bu durumun yanıltıcı olduğu gerçeğiyle karĢılaĢırız. zira tasavvufi düĢünce sistemine göre varlık, “bir”dir. dolayısıyla da “maĢuk/aranılan” o olduğu gibi, “âĢık/arayan” da o‟ndan baĢkası değildir ve olamaz da. zira o, bütün zıtlıkları kendisinde birleĢtirdiği gibi, “eylem”i ve “eylemsizlik”i de kendisinde birleĢtirir. bu husus, “kozmik çark” sembolizminde de kendisini açık bir Ģekilde göstermektedir. zira söz konusu sembolizme göre “merkez”, “hareketsiz” olmakla birlikte, tüm hareketin kaynağıdır: “bu merkez, tezahür etmemiĢ olarak ya da daha çok tezahür etmemiĢ olduğu için aslında etkinlikle dolu olan -zira o, tüm özel etkinliklerin kendisinden türemiĢ oldukları her Ģeyi yönetir ve- ilkesel etkinliktir. Öyle ki, lao- tse bunu Ģöyle ifade eder „ilke daima durağandır, ancak her Ģey onun tarafından yapılır‟ ” (guenon , ). pervâne için geçerli olan “eylem” hâlinde olma durumu, tasavvufi düĢünce sistemindeki baĢka bir hususla da çok yakından ilgilidir. zira tasavvufta, insanın ayrı düĢmüĢ olduğu sevgili‟ye kavuĢması için çaba harcaması gerekir: “gerçekten, Ġslâm mistisizmi pasif olmaktan ziyâde aktif tarafıyla dikkati çekiyor. sûfî vecd hâlinde allah‟ın iradesine teslim olmuĢtur ve pasiftir, fakat o noktaya gelmek için aktif bir Ģekilde hazırlanmıĢ ve kendisini „ilham‟ alabilecek hâle getirmiĢtir” (güngör , - ). daha önce de bahsetmiĢ olduğumuz gibi pervâne/insan, mumun/sevgili‟nin çağrısı (alev) neticesinde o‟na yönelmiĢ, dolayısıyla da eyleme geçmiĢ olur. baĢka bir deyiĢle “uyanıĢ”, “arayıĢ”a kapı aralamıĢ ve bu sayede aĢk, “eylem”e dönüĢmüĢtür. ĠĢte bu noktadan itibaren pervâne/insan, bütün dikkatini ve enerjisini sevgili‟ye kavuĢma hedefi üzerinde yoğunlaĢtıracaktır: “ĠĢte bu biçimde daha iyi bir hayat imgesine ulaĢtığında uyanan kiĢi, bir arayıcı olur ve bu imgeyi bütün imgelerden daha değerli bulur. bu imge ile güdülenir, onu özler, ona ilgi duyar ve onunla bir olmak için tüm gayretini onu elde etmeye yöneltir” (arasteh , ): ta yüzün Ģem„ından ırag olmıĢam pervâne tek yanaram leyl ü nehâr iy nûr-ı nûrum handasan nesîmî ( / ) alevin cazibesine kapılarak muma yaklaĢan ve onun etrafında dönüp durmaya baĢlayan pervânenin içinde bulunduğu durum, insanın/sâlikin allah‟a ulaĢma yolunda gösterdiği gayreti güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer ifade eder. bu çabanın sonuca ulaĢabilmesi ise ancak pervânenin/sâlikin mumun alevinde/sevgili‟de “yok olma (fenâ)” sıyla gerçekleĢebilecektir. zira uyandıktan sonra, yeniden doğmak (bekâ) için ölmek (fenâ) gerekmektedir (needlemann-skynner- ingleby , ). “arayıĢ”, ancak bu sayede “buluĢ”a dönüĢecektir. iĢığıyla (nûr) pervâneyi kendisine çeken mum/alev, ısısıyla (nâr) da onu “yokluk”a taĢıyacak potansiyeli barındırmaktadır. ancak “birliğin son hedefine ulaĢması, insanın kusurlu varlıklar dünyasına âit her Ģeyden uzaklaĢmasıyla mümkün olacak” (güngör , ), hatta âĢığın bu uğurda “cân”ını bile feda etmesi gerekecektir. zira “hiçbir mahluk ölmeksizin, bir üst varlık seviyesine, yani eskiden olduğu hâle (hakikatine) yükseleme(mektedir)” (livingston , ). hâlbuki bunlar, her insanın göze alabileceği, yapabileceği Ģeyler değildir. nitekim insan, “beden” ve “ruh” olmak üzere iki unsurdan müteĢekkildir ve ruh yönü onda “ulvî” arzuların doğmasına ve geliĢmesine zemin hazırlarken beden/nefs yönü ise onu “süflî” arzulara sürükleyebilmekte, hatta “uyanıĢ”ı yaĢamıĢ olmasına rağmen, bu yolda sonuca ulaĢamamasına bile sebep olabilmektedir: “Ġnsanın tabiatı, kolayca mükemmelliğe yönelmez. sezgisiyle daha iyi bir hayatın farkına varırken (…) içgüdüleri, dürtüleri ve bencil güdüleri veya nefs, kendisini aĢağıya çekebilir” (arasteh , ). nitekim “Ġbn arabî (de) yeryüzüne bitiĢik olup kuĢlar gibi yukarılara yükselememesinden dolayı insanın beden yönünün tabiatını „kayalar‟la sembolize etmiĢtir” (mahmûd , ). ancak mumun etrafında dönüp durmaya baĢlayan pervâne/sâlik için böyle bir durum söz konusu değildir. o, bütün çeliĢkilerden ve korkulardan arınmıĢ bir Ģekilde “hedef (merkez)”e yoğunlaĢmıĢtır. Öyle ki korkusuzluk (pervâ ne), onun adıdır (pervâne): tâlib-i Ģem„-i vasl olınca kiĢi oda yanmakdan ana pervâ ne bâkî (g / ) cân ü dil yaksam n‟ola cânâ yüzün Ģem„ine kim bâl ü perden „âĢık-ı pervânenin pervâsı yok ahmet paĢa (g / ) “ezelde allah insanlarla bir ahde girmiĢtir ve tevhîd o ahdi yerine getirmek, geldiği yere dönmek mânâsına gelir. nitekim cüneyd‟e tevhîdin manası sorulduğunda „olmadan önce olduğun hâle dönmektir‟ de(miĢtir)” (güngör , ). bu “olmadan önce olduğun hâle dönmek” durumu, bedenle kayıtlanarak dünyaya inen/düĢen ve gittikçe madde âleminin kesafeti içine dalan insan için ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bir “arınma” sürecine iĢaret etmektedir. arınmayı sağlayacak olan Ģey ise “aĢk/ateĢ”tir. zira aĢk/ateĢ, “maddeyi ayrıĢtır(ır) ve katkıları yok ed(er). baĢka bir deyiĢle, ateĢten geçen bir Ģey türdeĢleĢir, böylece arılaĢır” (bachelard , ). muma yaklaĢıp onun etrafında dairesel hareketlerle dönmeye baĢlayan pervâne, merkeze yaklaĢtıkça çekimin de artmasına bağlı olarak ateĢe gittikçe daha da yaklaĢır, yaklaĢtıkça da hareketi hızlanır. merkezin cazibesine kapılmıĢ bir Ģekilde onun etrafında durmadan dönen pervânenin bu hâli, sevgili‟ye artık oldukça yakın bir mesafede olmanın ortaya çıkardığı sevincin sebep olduğu bir nevi “sarhoĢluk” hâlidir: girip semâ„a eder gâyet-i sürûrundan lisân-ı hâl ile Ģem„e durûd pervâne nâilî (g / ) kalır piyâlesi Ģem„in lebâleb ü serĢâr teraĢĢuhunda olur bî-Ģu„ûr pervâne nâilî (g / ) “merkez”e yakın olmak, pervânenin mumun etrafında çizdiği çemberin yarıçapını da gittikçe kısaltır, baĢka bir deyiĢle mumun etrafında çizdiği çember aĢama aĢama daralır. artık “mum/sevgili/merkez” ve “pervâne/âĢık/çevre” arasındaki mesafe kapanmak/sıfırlanmak üzeredir. ancak bu aĢamada, söz konusu mesafenin kapanmasını engelleyen bir engel vardır. bu, pervânenin “kendi varlığı”, baĢka bir deyiĢle “bedenî varlık”ıdır. zira “bireyin kiĢilik dediği Ģey, gerçekte onun potansiyel kiĢiliğini gölgelemekte ve olgunlaĢmasını engellemektedir. onun kiĢilik dediği Ģey gerçekten de onun gerçek kiĢiliğini gizleyen Ģeydir ve onun için „ben‟ olan, gerçekte onun „ben‟ olması için engeldir (arasteh , ). dolayısıyla da vuslatı engelleyen bu “perde/engel”in aĢk ateĢinde yok edilerek aradan kaldırılması gerekmektedir. bu, vuslata/birliğe ulaĢmanın temel Ģartını teĢkil etmektedir: pervâne gibi yanmayıcak nâr-ı „aĢka ten ol Ģem„-i hüsne vasl olımazsın cihânda sen ġeyhülislâm yahyâ (g / ) terk-i ağyâr ile herkes vâsıl-ı yâr oldu lîk gâlibin ağyârı gâlibdir hicâb oldur ki ol ġeyh gâlib (g / ) güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer “ben” olabilmek için, “ben” ortadan kaldırılmalıdır. ancak tasavvufi düĢünce sistemine göre, bu aĢamaya ulaĢabilmek için bunun öncesinde “hazırlık” niteliğindeki birtakım aĢamalardan geçilmesi gerekmektedir. pervâne/sâlikin, sevgili‟nin çağrısının ardından ona doğru yönelip mumun alevine oldukça yakın bir durumda konumlanmasına kadarki süreç, söz konusu hazırlık aĢamasına tekâbül etmektedir. pervâne/sâlik, bu aĢamaya kadar oldukça “aktif” bir hâldedir ki bu durum, tasavvufi düĢünce sistemindeki “aktiflik (gayret)” ilkesiyle tam olarak örtüĢmektedir. dolayısıyla da artık alevin hemen yanı baĢında olan pervâne/sâlik, vuslata ulaĢmak için gerekli olan Ģeylerden kendi üzerine düĢen her Ģeyi yapmıĢtır. geriye ise “beden (ben)”in ortadan kaldırılması kalmıĢtır. ancak bu, pervâne/âĢığın kendisinin yapabileceği bir Ģey değildir. dolayısıyla da bu noktada artık âĢığın, sevgili‟nin yardımına ihtiyacı vardır. bu aĢama, seyr ü sülûku meydana getiren yedi aĢamadan altıncısına tekâbül etmektedir: “bu altıncı makama kadar, ma‟nevî yolcu, makamları mücâhede ile elde eder, fakat altıncı makamdan yedinci makama geçebilmek için mutlaka hakk‟ın cezbesi, yani ma‟nevî yolcuyu bizzat hakk‟ın kendine çekip kavuĢturması gerekir” (sunar , ). yani pervâne/sâlik, mum/merkez/allah‟a yaklaĢmak için gerekli olan tüm çabayı ortaya koymuĢtur. bundan sonra gerekli olan Ģey ise allah‟ın cezbesiyle onu kendine çekip “fenâ”ya ulaĢtırmasıdır. ĠĢte pervânenin ateĢin etrafında dönüp dönüp en sonunda aniden bu ateĢte yanması, çaba sarf ederek belli bir aĢamaya gelmiĢ olan kulunu, allah‟ın, cezbesiyle bir anda kendisine çekerek vahdete ulaĢtırması anlamına gelmektedir. baĢka bir deyiĢle, hakk‟ın cezbesine mazhar olan âĢık, sevgili tarafından, tıpkı pervâne gibi aniden “ateĢ”in içine çekilmektedir: ġem„a diyen râzını pervâne tek Çâresi yanmagdur anun ya nedir nesîmî ( / ) söz konusu aĢamada, pervâne/sâlik için söz konusu olan “aktiflik”, yerini artık “pasiflik”e bırakmaktadır. Çünkü artık “gayret” değil, “bekleyiĢ” vardır: “bu sınıra kadar ulaĢmak ve aldatıcı Ģeylerden yüz çevirerek orada devamlı kalmak insanın kudreti dâhilindedir; ama allah teâlâ‟nın rahmetini kendine celbetmek onun elinde değildir. ama insan bunları yerine getirmek suretiyle ilahî rahmet nefhalarını alacak duruma gelmiĢtir ve yapacağı bütün iĢ allah teâlâ‟nın ona, tıpkı bu yoldan peygamberlere ve velîlere yaptığı gibi, rahmetinden lutfedeceği Ģeyleri beklemekten ibarettir” (güngör , ). ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bu husus, allah ve insan arasındaki aĢkın tek taraflı değil, karĢılıklı bir aĢk olmasıyla, baĢka bir deyiĢle aĢkın sadece insandan allah‟a değil, aynı zamanda allah‟tan da insana yönelmiĢ olmasıyla da yakından ilgilidir. ancak bu noktada, o‟nu sevmiĢ olmak, o‟nun tarafından sevilmiĢ olmanın ön koĢulu durumundadır: “sâlikler allah‟ı bir sevdiler mi, karĢılığında o‟nun tarafından sevilirler. sonra allah aĢkının onları sarhoĢ etmesi ve onların tüm insanî duygularını ve sınırlanmıĢlıklarını yok etmesi imkân dâhiline girer. bu durum, yerine allah‟ın ezelî-ebedî varlığının parıltısını bırakarak, gelip geçiciliğin ve mümkün oluĢun karanlığını sıyırıp alabilir” (chittick , ): nâra atan cânını çün Ģem„ içün pervânedür nârına Ģem„ ol sebebden yandurur pervâneyi nesîmî (g / ) pervâne/sâlikin, etrafında dönüp durduğu ateĢin içine sevgili tarafından aniden çekilmesi neticesinde “pervâne/sâlik” ve “mum/sevgili” arasındaki son engel durumunda olan “ben”in aradan kalkmasıyla beraber, “merkez-çevre/sevgili-sâlik” arasındaki mesafe de kapanmıĢ/sıfırlanmıĢ olur. bu durum, aynı zamanda yaratmayla beraber açılan varlık halkasının da kapanması/tamamlanması anlamına gelmektedir. zira ateĢ, dokunduğu her Ģeyi kendisine dönüĢtürür. baĢka bir deyiĢle, yanan her Ģey, bizzat ateĢin kendisi olur. pervâne/sâlik söz konusu olduğunda bu “ateĢ olma” durumu, “fenâ”ya tekâbül eder ki bu aĢama, varlık halkasının son aĢamasını meydana getirmektedir. ancak pervânenin dönüĢtüğü ateĢ, yakan ve yok eden ateĢ (nâr) değil, aydınlatan ateĢ(nûr)‟tir: yakıp vücûdunu eyler kebûd pervâne görünce Ģem„i hem-âgûĢ-ı dûd pervâne nâilî (g / ) ol Ģem„a karĢu yananun küllî vücûdı nûr olur ol od bu oda benzemez hîç belürmez zebânesi yunus emre (g / ) harîr-i Ģu„leye tebdîl edip libâs-ı teni fenâda anladı zevk-ı hulûd pervâne ġeyh gâlib (g / ) pervâne/sâlik, “bu dünyada çılgınlık sayılan aĢkıyla, öteki âleme ait idraki bulur, bu idrakle mâĢûğuyla hakikî birliğe kavuĢur” güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer (andrews , ). zira aĢk/ateĢ, pervâne/sâlikin varlığını ortadan kaldırmak suretiyle yaratma neticesinde ortaya çıkan “ikilik”i, tekrar “birlik”e dönüĢtürmüĢ, baĢka bir deyiĢle âĢık ile maĢuk arasındaki fark ortadan kalkmıĢ ve âĢık, maĢuk; maĢuk ise ÂĢık olmuĢtur: eylemez halvet-sarây-ı sırr-ı vahdet mahremi „ÂĢıkı ma„Ģûktan ma„Ģûku „âĢıktan cüdâ fuzûlî (g / ) pervâne/sâlik, bu aĢamaya ancak “ben (beden)”ini fedâ ederek ulaĢmıĢtır. dolayısıyla da onun varlığı, sevgili‟nin varlığı içinde erimiĢtir. bu nedenle de pervâne/sâlikin artık kendisine ait bir varlığı yoktur (fenâ); ama o, artık sevgili‟yle beraber “var (bekâ)”dır: zihî ta„alluk-ı pervâne kim yanar kül olur Ölünce Ģem„-i Ģeb-efrûzdan cüdâ düĢmez nâilî (g / ) pervâne/sâlik, aĢk ateĢinde yanmadan önce “bî-karâr”dır. baĢka bir deyiĢle, tam bir “hareketlilik” içindedir. ancak fenâya ulaĢmayla birlikte, “hareketlilik” hâlinden “dinginlik” hâline geçer. bu husus, bir taraftan pervânenin yanarak ölmesi ve bunun neticesi olarak hareketsiz bir hâle gelmesi -ki hareketsizlik ölümün doğal bir sonucudur- gerçeğiyle, diğer taraftan ise seyr ü sülûkun son aĢamasına ulaĢmıĢ olan sâlikte ortaya çıkan içsel hâl ile ilgilidir. nitekim “kökenine (yani, tüm varlıkların ilk kaynağı ve nihaî sonu olan -ya da ezelî ve ebedî olan- ilkeye) dönmek, dinlenme hâline girmektir” (guenon , ). “zira kesretin içerdiği tüm zıtlıkları aĢmıĢ olması nedeniyle, o artık hiçbir Ģeyden etkilenmez: o, tam bir eriĢilmezliğe ulaĢmıĢtır. yaĢam ve ölüm onun için aynı derecede önemsizdir, onda hiçbir heyecan doğurmaz” (guenon , ). böyle bilinç seviyesine ulaĢmıĢ olmak, aynı zamanda “özgürlük”e kavuĢmuĢ olmak anlamına gelmektedir: rumûzât-ı dehenden hurde-bîn-i râz olan hâtır cihânın hîç teng olmaz gam-ı bûd u nebûdundan ġeyh gâlib (g / ) sanma pervâneleri yakdı oda Ģem„-i münîr Çevirüp baĢına her birini âzâd itdi mesîhî (g / ) ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer “Ġnsan/bilen”in, “allah/bilinen”de yok olması (fenâ) neticesinde, “bil(in)mek” de gerçekleĢmiĢ olur. burada söz konusu olan bilgi, herhangi bir varlığa ait olan alelâde bilgi değil, allah‟a iliĢkin bilgi (marifet)‟dir ve ancak “bilen” varlığın “bilinen” varlıkta kendini yok etmesi neticesinde varlık halkasının tamamlanması/kapanması (devrin tamamlanması) sayesinde ortaya çıkmıĢtır. bununla beraber söz konusu bilgi, mutasavvıflar tarafından sürekli olarak “anlatılamaz” olarak vasıflandırılmıĢtır. marifet için kullanılan “tatmayan bilmez” Ģeklindeki ifade, söz konusu bilginin aktarılamayacağına iĢaret etmenin yanında, onun Ģahsi bir tecrübenin ürünü olduğunu da ortaya koymaktadır. dolayısıyla da marifet, zihinler arasındaki bir aktarımı mümkün kılmayan, ancak deneyimlenerek öğrenilen bir bilgidir. bu bilgi ancak “aĢk ateĢi”nde yanmanın neticesi olarak ortaya çıkmıĢtır ki, bu noktada “ateĢ/aĢk” ve onun sonucu olarak ortaya çıkan “bilgi”, aynı niteliğe sahip olma noktasında birleĢmektedirler. zira marifetin ne olduğunu anlamak için onu tecrübe etmek gerektiği gibi, ateĢ hakkında tam bir bilgiye sahip olmanın yolu da onu tecrübe etmekten geçmektedir: kim ki pervâne-sıfat „ıĢkuna yanmaz ne bilür ne bilür Ģol yine kim pertev-i envâr nedür nesîmî (g / ) pervânelerin “Ģem„den haberdâr olma” arzularını ve bu yoldaki çabalarını anlatan aĢağıdaki hikâye, marifetin söz konusu bu özelliklerini tam olarak yansıtan bir nitelik taĢımaktadır: “bir gece pervâneler toplanarak, Ģem„e kavuĢmak isterler. „birimizin gidip, ondan haber getirmesi gerek‟ derler. pervânelerden biri gider ve uzaktan Ģem„in kasrını görür. geri döner ve gördüklerini anlatır. tenkidci olan pervâne, onun Ģem„den bîhaber olduğunu söyler. bunun üzerine bir baĢka pervâne gider. nûrdan geçerek Ģem„e atılır. kanatlarını çırpar. ama o da geri döner ve bir miktar sır söyler. tenkidci pervâne onu da eleĢtirir. bir baĢkası kalkıp gider. sarhoĢça dans ederek ateĢe konar; ona sarılarak kendini kaybeder. her yanı ateĢ gibi kızarır. tenkidci pervâne onu uzaktan görünce, „ĠĢte Ģem„den haberdâr olan budur‟ der” (kanar , - ). bu hikâyede, pervânenin mumun alevini uzaktan görmesi, sonra ona yaklaĢarak ısısını hissetmesi ve son olarak da bu alevde yanması Ģeklinde üç aĢamadan meydana gelen macerası, üç ayrı pervâne vasıtasıyla iĢlenmiĢtir. bu pervânelerden ilk ikisi, Ģem„ hakkında ancak kısmi bir bilgi edinebilmiĢtir. “ġem„den tam olarak güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer haberdâr olabilmek” için ise üçüncü pervânenin kendisini Ģem„e fedâ etmesi gerekmiĢtir. hikâyede karĢımıza çıkan bu “üçleme”, marifetin elde edilmesini sağlayan sürecin üç aĢamasına tekabül etmektedir. bunlar “ilme‟l-yakîn”, “ayne‟l-yakîn” ve “hakke‟l-yakîn”dir. pervânenin mumun ıĢığını ilk gördüğü andaki bilgisi, “ilme‟l-yakîn” mertebesindedir. zira bu aĢamada alevin sadece “ıĢık”ından haberdârdır. bu ise alev hakkında bir bilgi olmakla beraber, eksik bir bilgidir. pervâne aleve yaklaĢınca onun aynı zamanda bir “ısı kaynağı” olduğunu da öğrenmiĢ olur. böylece alev hakkındaki bilgisi artmıĢtır. ama yine de eksik bir bilgidir. zira alev, aynı zamanda “yakan” bir Ģeydir. dolayısıyla da pervânenin bu aĢamadaki bilgisi “ayne‟l-yakîn” mertebesindedir. pervâne alev etrafında çizdiği çemberi gittikçe daraltıp en sonunda da kendisiyle alev arasındaki mesafeyi kapatınca, baĢka bir deyiĢle etrafında döndüğü alevde yanınca onun alev hakkındaki bilgisi “hakke‟l-yakîn” mertebesine yükselmiĢ olur. zira o artık, alevin hem “aydınlatan” hem “ısıtan” hem de “yakan” bir Ģey olduğunu öğrenmiĢtir. pervâne, mumun alevinde yanarak onun hakkında en kesin bilgiyi (hakke‟l-yakîn) elde eder; ama bu bilgiyi edinmenin bedeli olarak bedenî varlığını feda ettiği için, yaĢadığı tecrübeyi, yani ateĢ hakkında edindiği bilgiyi geri dönerek diğer pervânelere aktaramaz. zira o, “bilgi”yi bulduğu anda “maddi varlığı”nı kaybetmiĢtir. dolayısıyla da pervânenin Ģem„le olan macerasında, Ģem„ hakkında “tam” bir bilgi sahibi olabilmek için cânı fedâ etmek gerektiğinin vurgulanıyor olması, marifetin tecrübi bir bilgi olması hususuna iĢaret etmenin yanında, aynı zamanda marifetin aktarılamaz oluĢu gerçeğine de tekabül etmektedir. ahmed gazzâlî, bu gerçeği Ģu sözlerle ifade eder: “aĢk, âĢığı bütünüyle kaplamadıkça âĢıkta bir taraf eksik kalır; öyle ki âĢık, burada olup biteni zahirî bilgi yoluyla aktarabilir. ama aĢk, âĢığın varlık mülkünü tamamen kuĢatınca arada haber alacak ve gıdalanacak hiçbir Ģey kalmaz. aĢk daha da derinlere nüfuz edince, bilginin zahirî (dıĢ yüzü) sır perdesinin derûnundaki madeni bulamaz. evet, buluĢ gerçekleĢmiĢtir; ama bu buluĢla ilgili haber yoktur; çünkü bir özdeĢleĢme vardır. değil mi ki, „Ġdrak, idrakin aczini idraktir‟ sözü buna iĢaret etmektedir” ( , ). bütün bunlardan da anlaĢıldığı gibi “aktarılamaz olma”, marifetin en temel niteliklerinden birini teĢkil etmektedir. buna bağlı olarak da klasik türk Ģiirinde çoğu kez bu özelliğiyle karĢımıza çıkmaktadır: ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer hafîdir hüsn-i ma„nâ gibi gâlib bilen vasf edemez ma„nâ-yı hüsnü ġeyh gâlib (g / ) hep cân atıyor halk fenâ mülküne ammâ bir hârice çıkmaz ki ne hâlet var içinde ġeyh gâlib (g / ) ġahsi bir tecrübenin sonucunda elde edilmesi, marifete “sübjektif” olma vasfını da kazandırmaktadır. zira bu bilgi ancak yaĢanarak öğrenebildiğine göre, yaĢayan kiĢiye göre değiĢiklik arz etmesi de kaçınılmaz olmaktadır: bir midir mey hum u sâgarda leb-i sâkîde fark eder neĢ‟e-i „irfân gönülden gönüle ġeyh gâlib (g / ) bu noktada, marifetle ilgili olarak bir baĢka gerçeğe de iĢaret etmek gerekmektedir. söz konusu bilginin ortaya çıkması aĢamasında “insan” ve “allah”, sırasıyla “bilen” ve “bilinen” konumundadırlar ve bunlar, bilginin/marifetin ortaya çıkabilmesi için gerekli olan zorunlu “ikilik”i meydana getirmektedirler. ancak bu ikilik, “itibari” bir durumdur. Çünkü var olması mutlaka gerekli olan allah‟ın (vâcibü‟l-vücûd) vücudu dıĢında herhangi bir varlık yoktur. dolayısıyla da varlık/vücûd “bir”dir. (vücûd-ı mutlak) kâinat ve onun özü/özeti olan insan ise allah‟ın bilinmek için tecelli etmesi neticesinde ortaya çıkmıĢ birtakım görünüĢlerden ibaret olup gerçek bir varlığa sahip değildir. dolayısıyla “bilen” de “bilinen” de tek varlık olan allah‟tan baĢkası değildir. o, “bilen” konumundayken insan, “bilinen” konumundayken ise allah‟tır. böylece allah, “bilen/insan” ve “bilinen/allah” olmak üzere, zahirde meydana gelen bu ikilik vasıtasıyla kendini bilir. “bu, „varlık kendisini kendisi vasıtasıyla bilir‟ ibaresiyle ifadelendirilen durumdur” (guenon , ). onun aynı zamanda hem özne hem de nesne olduğu biçimindeki önerme ise “varlık, „varlık‟tır” Ģeklinde ifadesini bulur (guenon , ). “bilen” ve “bilinen”in aynîleĢtiği noktada, “güzellik” ve “aĢk” da aynîleĢir. zira söz konusu aĢama, “vahdet (birlik)” aĢamasıdır ve orada hiçbir “ikilik”e yer yoktur. dolayısıyla orada güzellik ve aĢk, birbirinden ayrı Ģeyler değildir: güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer müttehid hüsn ü mahabbet ne nizâ‟ u ne cedel müdde„î mahkeme-i „aĢkda gavgâ sığmaz nâilî (g / ) bu durum aslında, yaratılıĢın baĢlangıç aĢamasıyla seyr ü sülûkun son aĢamasının aynı noktaya tekabül etmesinin bir sonucudur. zira varlık halkasının tamamlanması anlamına gelen “devr”, cüneyd-i bağdâdî‟nin “nihâyet, bidâyete dönüĢtür” (Ġsmail hakkı bursevî , ) Ģeklindeki ifadesinden de anlaĢıldığı gibi, baĢlangıç noktasına geri dönmektir. nitekim bir çember üzerinde sürekli olarak aynı yönde ilerlendiği zaman, baĢlanılan noktaya geri dönülmektedir ki, devir nazariyesi de karĢılıklı iki yayın (kavs-i nüzûl ve kavs-i urûc) oluĢturduğu bir halka (çember) Ģeklinde sembolize edilmektedir. bu noktada zihinlerde Ģu soru belirir: baĢlangıç aĢaması ve son aĢama aynı olduğuna göre, “devr”in amacı nedir? daha önce de ifade etmiĢ olduğumuz gibi yaratılıĢ, allah‟ın “bilinme isteği”nin sonucu olarak gerçekleĢmiĢtir. devri tamamlayan insan, yaratılıĢın gayesinin gerçekleĢmesi noktasında bir “vasıta” fonksiyonunu yerine getirmektedir. zira “gizli hazine/mutlak güzellik” onun vasıtasıyla “sevilmiĢ” ve “bilinmiĢ” olmaktadır. sevilmek ve bilinmek ise güzelliğe değer katar. dolayısıyla da güzelliğin anlam ve değer kazanabilmesi için, o güzelliğe yönelmiĢ bir aĢkın olması gerekmektedir. ĠĢte insanın serüveni, bu gerekliliğin sonucudur. klasik türk edebiyatı Ģairleri aĢkı, güzelliğe anlam ve değer kazandıran bir unsur olarak göstererek bu gerçeğe iĢaret ederler: zahm-ı nigâh-ı „âĢık olur hüsne feyz-bahĢ gül-bûsedir o gül-bedenin güldüren yüzün ġeyh gâlib (g / ) var ise seng-i siyâh-ı kalb-i „âĢıkdır mihek yohsa o Ģûhun „ayâr-ı hüsn ü ânın kim bilir nâilî (g / ) nitekim bülbülün aĢkı olmasa gülün güzelliği bir değer ifade etmeyecektir. Çünkü gülün güzelliğine anlam ve değer katan Ģey, bülbülün feryatlarıdır: „aĢk eğer bâzârını germ etmese bülbül gibi hüsn olur vakt-ı Ģitâ içre açılmıĢ gül gibi ġeyh gâlib (g / ) “o, ilktir, sondur…” (kur‟ân, hadîd: ). ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer yek-rengdir zebân-ı hakîkatda hüsn ü „aĢk bâng-ı hezâr Ģu„lesidir âteĢ-i gülün ġeyh gâlib (g / ) bununla beraber, aĢk sadece “güzellik”e değil, “güzellik”e değer katması sebebiyle aĢkı yüreğinde taĢıyan insana da değer katmaktadır: gör iltifât-ı „aĢk ile bu kadr ü câhımız kâlâ-yı hüsne kıymet olur kem nigâhımız ġeyh gâlib (g / ) bütün bunları, “Ģem„ ve pervâne” sembolizmiyle ilgili olarak değerlendirdiğimizde oldukça ilginç bir gerçekle karĢılaĢırız. nitekim pervânenin yandığı anda alevde ani bir parlama meydana gelir, alev harlanır. ġairin tabiriyle “pervâne yanınca Ģem„in nûru „tamâm‟ olur”: ahmedâ yan bu „aĢk oduna ki Ģem„ nûru olmaz yakılmayınca tamâm ahmet paĢa (g / ) ĠĢte bu gerçek, insanın yeryüzü macerasının özeti durumundadır. mumun alevinde yanan, baĢka bir deyiĢle “devr”i tamamlayan insan, “güzellik”i kemâl noktasına taĢır. zira bu yanıĢ olmasa “güzellik”, tam olarak bilinmemiĢ ve sevilmemiĢ olacak, dolayısıyla da pervânenin mumun alevinde yanmasıyla ortaya çıkan son parıltı “eksik” kalacaktır. sonuç en temel kavramı “aĢk” olan klasik türk edebiyatında, “âĢık/bilen” ve “maĢuk/bilinen” ikilisini karĢılamak ve bunlar arasındaki iliĢki biçimini yansıtmak üzere çeĢitli unsurlardan faydalanılmıĢtır. ÇalıĢmamızın konusunu teĢkil eden “Ģem„ ve pervâne” ikilisi de klasik türk edebiyatında, “âĢık/bilen- maĢuk/bilinen” ikilisini ve iliĢkisini anlatmada kullanılan sembolik unsurlardan biridir. bu unsurlardan pervâne, âĢığı temsil ederken Ģem„ ise maĢuk fonksiyonunu yüklenmiĢ durumdadır. bunların Ģiir dünyası içinde kendilerine bu Ģekilde bir yer bulmuĢ olmaları ise söz konusu iki unsur arasındaki iliĢki biçiminin, aĢk iliĢkisi Ģeklinde yorumlanmıĢ olmasının bir sonucudur. güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer pervâne, sevgilisine kavuĢma yolunda canını feda etmekten çekinmeyen gerçek bir âĢıktır. ancak “Ģem„ ve pervâne” sembolizminde aĢk, sadece pervâneyle ilgili olan bir kavram olarak değil, en az pervâne kadar Ģem„i de ilgilendiren bir kavram olarak karĢımıza çıkmaktadır. zira -klasik türk edebiyatındaki aĢk-ateĢ benzetmesine bağlı olarak- baĢında yanan ateĢ ve bu ateĢin sonucu olarak akıttığı gözyaĢlarıyla Ģem„, tam bir âĢık görünümündedir. pervâneyi âĢığın sembolü durumuna getiren Ģey ise aĢk ve ateĢin her ikisinin de benzer özelliklere sahip olması ve benzer sonuçlar ortaya çıkarmasıdır. buna bağlı olarak da “Ģem„ ve pervâne” sembolizminde aĢk, her iki unsur için de geçerli bir kavram ve ortak bir nokta olarak karĢımıza çıkmaktadır. “ġem„ ve pervâne” sembolizmi, aĢkı, yaratıcı‟dan baĢlayarak anlatmaktadır. zira Ģem„ önce kendi yanmakta, daha sonra ise ateĢiyle pervâneyi yakmaktadır. aĢkın yaratıcı‟yla ilgili olan boyutu, varlık halkasını oluĢturan yaylardan ilki olan kavs-i nüzûla, pervânenin Ģem„e kavuĢma gayreti ise kavs-i urûca tekabül etmektedir. dolayısıyla da bu halkanın ilk yayını Ģem„in yanıĢı oluĢtururken ikinci yayını ise pervânenin yanıĢı oluĢturmaktadır. böylece, yaratıcı‟nın bilinmeye duyduğu aĢkla açılan varlık halkası, pervânenin Ģem„in ateĢinde yanmasıyla beraber kapanmaktadır. varlık halkasını meydana getiren yaylardan ilki olan kavs-i nüzûl, allah‟ın bilinmeye duyduğu aĢk neticesinde tecelli etmesi sürecini ifade etmekte iken, ikinci yay olan kavs-i urûc ise “dip nokta” konumunda olan dünyaya inerek/düĢerek “devr”i tamamlama vazifesini yüklenmiĢ olan insanın baĢladığı noktaya geri dönmek amacıyla gerçekleĢtirdiği manevî yolculuğunu ifade etmektedir. yaratılıĢ, allah‟ın “bilinme isteği”nin sonucu olarak gerçekleĢmiĢtir. “devr”i tamamlayan insan ise yaratılıĢın gayesinin gerçekleĢmesi noktasında bir “vasıta” fonksiyonunu yerine getirmektedir. zira “gizli hazine/mutlak güzellik”, onun vasıtasıyla “sevilmiĢ” ve “bilinmiĢ” olmaktadır. bu, insanın yeryüzü macerasının özetidir. ġem„in alevinde yanan, baĢka bir deyiĢle “devr”i tamamlayan insan, “güzellik”i kemâl noktasına taĢır. zira bu yanıĢ olmasa “güzellik”, bilinmemiĢ ve sevilmemiĢ olacaktır. ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer kaynakÇa ahmed gazzâlî ( ), aşkın hâlleri (çev. turan koç-m. Çetinkaya), gelenek yayıncılık, Ġstanbul ahmet paĢa ( ), ahmet paşa dîvânı (hzl. ali nihat tarlan), akçağ yayınları, ankara andrews, walter g. ( ), Şiirin sesi toplumun Şarkısı (çev. tansel güney), ĠletiĢim yayınları, Ġstanbul arasteh, a. reza ( ), aşkta ve yaratılışta yeniden doğuş (çev. bekir demirkol-Ġbrahim Özdemir), kitâbiyât yayıncılık, ankara azîzüddîn nesefî ( ), İnsân-ı kâmil (çev. ahmet avni konuk), gelenek yayıncılık, Ġstanbul bachelard, gaston ( ), ateşin tinçözümlemesi (çev. nail bezel), Öteki yayınevi, Ġstanbul bâkî ( ), bâkî dîvânı (hzl. sabahattin küçük), türk dil kurumu yayınları, ankara chĠttĠck, william ( ), tasavvuf (çev. turan koç), Ġz yayıncılık, Ġstanbul demĠrel, gamze ( ), “ „ġem„ ve pervâne‟nin Ġçsel yolculuğuna dair felsefî bir yaklaĢım, türkiyat araştırmaları, s. , s. - devellĠoĞlu, ferit ( ), osmanlıca-türkçe ansiklopedik lûgat, aydın kitabevi yayınları, ankara dÜzen, Ġbrahim ( ), azîz nesefî’ye göre allah kâinat İnsan, furkan yayınları, Ġstanbul cebecĠoĞlu, ethem ( ), tasavvuf terimleri ve deyimleri sözlüğü, anka yayınları, Ġstanbul fuzûlî ( ), fuzûlî dîvânı (hzl. kenan akyüz vd.), akçağ yayınları, ankara guenon, rene ( ), yatay ve dikey boyutların sembolizmi (çev. fevzi topaçoğlu), Ġnsan yayınları, Ġstanbul gÜngÖr, erol ( ), İslâm tasavvufunun meseleleri, Ötüken yayınları, Ġstanbul Ġbn arabî ( ), İlahî aşk (çev. mahmut kanık), Ġnsan yayınları, Ġstanbul güzellik, aşk ve bilgi Üçgeninde… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer Ġsmail hakkı bursevî ( ), kenz-i mahfi (sad. abdulkadir akçiçek), kitsanyayınları, Ġstanbul kanar, mehmet ( ), fehmî ve Şebisterî’den Şem‘ ve pervâne, Ġnsan yayınları, Ġstanbul kur’ân-ı kerîm ve açıklamalı meâli (hzl. hayrettin karaman vd.) ( ), türkiye diyanet vakfı yayınları, ankara latîfî ( ), latîfî tezkiresi (hzl. mustafa Ġsen), akçağ yayınları, ankara lĠvĠngston, ray ( ), geleneksel edebiyat teorisi (çev. necat Özdemiroğlu), Ġnsan yayınları, Ġstanbul mahmûd, zeki necîb ( ), “Ġbn arabî‟de sembolizm”, İbn arabî anısına (makaleler), Ġnsan yayınları, Ġstanbul mesîhî ( ), mesîhî dîvânı (hzl. mine mengi), atatürk kültür merkezi yayınları, ankara nâ‟ilî ( ), nâ’ilî dîvânı (hzl. haluk Ġpekten), akçağ yayınları, ankara necâtî ( ), necâtî beg dîvânı (hzl. ali nihat tarlan), akçağ yayınları, ankara needlemann, j. –skynner, r. – ingleby, d. ( ), psikiyatri ve kutsallık (çev. abdullah haklı), Ġnsan yayınları, Ġstanbul nesîmî ( ), nesîmî hayatı edebî kişiliği, eserleri ve türkçe dîvânının tenkitli metni i-ii (hzl. hüseyin ayan), türk dil kurumu yayınları, ankara settârî, celâl ( ), züleyhâ’nın aşk derdi (çev. mehmet kanar), Ġnsan yayınları, Ġstanbul sunar, cavit ( ), tasavvuf felsefesi veya gerçek felsefe, anadolu aydınlanma vakfı yayınları, Ġstanbul ġeyh gâlib ( ), Şeyh gâlib dîvânı (hzl. muhsin kalkıĢım), akçağ yayınları, ankara ġeyhî ( ), Şeyhî dîvânı (hzl. mustafa Ġsen-cemal kurnaz), akçağ yayınları, ankara ġeyhülislâm yahyâ ( ), Şeyhülislâm yahyâ dîvânı (hzl. hasan kavruk), milli eğitim bakanlığı yayınları, ankara türkçe sözlük ( ), türk dil kurumu, ankara ayşegül akdemİr turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer yildirim, ali ( ), “bâkî‟nin devriyye türünde yazdığı bir gazeli”, fırat Üniversitesi sosyal bilimler dergisi, c. , s. , s. - yildirim, ali ( ), “renk simgeciliği ve ġeyh gâlib‟in Üç rengi”, milli folklor, c. , s. , s. - . yunus emre ( ), yunus emre dîvânı ii (tenkitli metin) (hzl. mustafa tatçı), kültür bakanlığı yayınları, ankara. zâtî ( ), zâtî dîvânı iii (hzl. mehmed ÇavuĢoğlu-m. ali tanyeri), Ġstanbul Üniversitesi edebiyat fakültesi yayınları, Ġstanbul. beautiful interfaces. from user experience to user interface design full terms & conditions of access and use can be found at http://www.tandfonline.com/action/journalinformation?journalcode=rfdj download by: [ . . . ] date: september , at: : the design journal an international journal for all aspects of design issn: - (print) - (online) journal homepage: http://www.tandfonline.com/loi/rfdj beautiful interfaces. from user experience to user interface design letizia bollini to cite this article: letizia bollini ( ) beautiful interfaces. from user experience to user interface design, the design journal, :sup , s -s to link to this article: http://dx.doi.org/ . / . . © the author(s). published by informa uk limited, trading as taylor & francis group published online: sep . submit your article to this journal view related articles view crossmark data http://www.tandfonline.com/action/journalinformation?journalcode=rfdj http://www.tandfonline.com/loi/rfdj http://dx.doi.org/ . / . . http://www.tandfonline.com/action/authorsubmission?journalcode=rfdj &show=instructions http://www.tandfonline.com/action/authorsubmission?journalcode=rfdj &show=instructions http://www.tandfonline.com/doi/mlt/ . / . . http://www.tandfonline.com/doi/mlt/ . / . . http://crossmark.crossref.org/dialog/?doi= . / . . &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . / . . &domain=pdf&date_stamp= - - design for next th ead conference sapienza university of rome - april doi: . / . . © the author(s). published by informa uk limited, trading as taylor & francis group. this is an open access article distributed under the terms of the creative commons attribution license (http://creativecommons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. beautiful interfaces. from user experience to user interface design letizia bollinia* adepartment of psychology, university of milano-bicocca *corresponding author e-mail: letizia.bollini@unimib.it abstract: the paper is aimed to explore and to conduct a critical review of the latest position in the debate of the aesthetic dimension of visual design applied to graphical, multimodal and virtual interfaces in the digital field and its impact on the experience of people. the relationship between form and function —aesthetic values and technical issues— has become the juxtaposition between graphic and usability in the digital field. the mobile revolution in has forced designers to rethink the interaction and interface concepts, since the introduction of the desktop metaphor in . the skeuomorphism style and the transition to flat patterns are a strong evidence of the ongoing discussion about the visual paradigms adopted. brutalism start by deville in is a deep reaction that recalls to design its role and its own value. keywords: interface design, visual language, brutalism in web design, skeuomorphism, flat design, material design . form follows function? starting from the vitruvian definition of the pillars of architecture: “haec autem ita fieri debent, ut habeatur ratio firmitatis, utilitatis, venustatis.” [“in tutte queste cose che si hanno da fare devesi avere per scopo la solidità, l'utilità, e la bellezza.”] (vitruvio, ) to the three element’s of the art & science of web design defined by jeffrey veen ( ), the issue of the aesthetic dimension in design disciplines is always central and critical. the relationship between form and function has become an explicit debate after the industrial revolution representing the opposite position of the aesthetic values and technical issues. the discussion involved along the evolution of design – intended as theoretical, practical and productive discipline – single personalities such as sullivan and whole school – the bauhaus above all – or intellectual movements. s d ow nl oa de d by [ . . . ] a t : s ep te m be r letizia bollini with the digital revolution the discussion as worsened in a juxtaposition between graphic and usability – user experience design vs. user interface design, in recent years – as well reported in many books and guidelines given by nielsen – the well-known usability guru – in the late ‘ s. in a series of best-seller books such as web usability ( ) or homepage usability ( ), nielsen gave a precise indication to “purge” interfaces from visual design and graphical elements in favor of a strict and orthodox respect of usability heuristic as if the visual language would interfere instead of supporting the human-computer interaction. although the community of web designers and developers actively supports the adoption of the user-centered approach and of web standards to guarantee accessibility to digital contents, where design of the visual elements – that means, most of the time, the quality of the figurative elements and message representation through the graphic language – were banned, the whole usability of the system fails, as well represented by the two interfaces of figure . figure . the homepage of “a list apart” the webzine founded by jeffrey zeldman to promote web standards and digital design future (on the left). the homepage of “useit” the jacob nielsen’s blog aimed to spread usability issues and approaches to web design (on the right). on the left the alistapart.com – the webzine homepage promoted by jeffrey zeldman author and evangelist of the web standard project movement ( - ) with aaron gustafson molly e. holzschlag, jeffery venn, dave shea etc. on the right the homepage of the jacob nielsen’s useit.com blog (both in the previous version). both publications are focused on web usability and standards, but the first one uses the basic rules of visual language – hierarchy, space, alignment, colors, typography – and creates a well-organized and pleasant interface that supports the users in building a strong mental model and cognitive comprehension of the structure. the aesthetic provides a clear and enjoyable experience. on the other hand, the nielsen’s site just creates two equal areas with no lecture and perception priority, link colors and the underline effect has a heavy visual impact without giving a rhythm to users when skimming and scanning the text. . missing in action according to the iso definition proposed and shared in : “usability is the ease of use and learnability of a human-made object such as a tool or device. in software engineering, usability is the degree to which a software can be used by specified consumers s d ow nl oa de d by [ . . . ] a t : s ep te m be r http://alistapart.com/ http://useit.com/ beautiful interfaces. from user experience to user interface design. to achieve quantified objectives with effectiveness, efficiency, and satisfaction in a quantified context of use” (iso - , ) if the first two parameters – effectiveness and efficiency – are well known, tested, and investigated, the third – satisfaction – is often ignored, although is the one aimed to evaluate the qualitative aspects of the experience such as pleasantness, comfort, and the overall appreciation of the users. quantitative performances of an interaction could be measured using criteria like time of execution, numbers of failures or succeeding in completing the tasks and so on. on the other hand, feedbacks on more personal opinions and feeling or emotional reactions are not as easy to collect and understand. therefore the human-computer interaction, usability, and user experience design debate have often ignored the “dark side” of user experience – that means the visual, aesthetic, and emotional aspects – in order to raise and consolidate a strong and shared method among theorists, scholars, and practitioners. the mantra of this cultural approach could be: “it’s ugly, but it works” and it is well exemplified by a lot of big portals and platforms of the first generation of websites – developed in the late ‘ s – and the web . era – introduced by the o’reilly definition in – i.e. wikipedia, reddit, craiglist (see figure ). they have millions of unique visitors, monthly page views and votes although they have no look & feel at all – visual values and interface design – they “just work” in solving a problem. besides this approach in building and evaluating website interactions based on usability culture of the late ‘ s and ‘ s, two japanese researchers, masaaki kurosu and kaori kashimura introduced in the concept of apparent usability opposite to inherent usability in digital systems. the experimental research looks at the statistical correlation between the two aspects of usability. what emerges from the study is that “the apparent usability is less correlated with the inherent usability compared to the apparent beauty which showed the correlation coefficient of . . this suggests that the user may be strongly affected by the aesthetic aspect of the interface even when they try to evaluate the interface in its functional aspects and it is suggested that the interface designers should strive not only to improve the inherent usability but also brush up the apparent usability or the aesthetic aspect of the interface” (kurosu & kashimura, : ). the results suggest to designers to improve the apparent usability, they mean, the aesthetic aspects of the interfaces. this shift of focus —from rational to emotional elements— restores the centrality of visual design and its languages. this issue has been widely and in-depth reviewed by other authors including tractinsky, katz & ikar ( ), donald norman ( and ), lavia & tractinsky ( ). in particular, the experimental studies conducted by tractinsky explicitly introduce again the concept of beauty and aesthetic proving and claiming the role of them in the user experience. “this study demonstrated once again the tight relationships between users' initial perceptions of interface aesthetics and their perceptions of the system's usability. moreover, we showed that these relations endure even after actual use of the system. we believe that these results shed new light on the role of aesthetics in hci design and its effects on how users experience their interaction with computerized systems. the results of this study are commensurate with social psychology findings that people associate a person’s physical attractiveness with other personal attributes. similarly, research in the areas of marketing and consumer behavior indicate that aesthetic features of the shopping environment are perceived as s d ow nl oa de d by [ . . . ] a t : s ep te m be r letizia bollini related to other, seemingly independent attributes (e.g. functional) of that environment. […] yet, we believe that there is sufficient evidence already to justify the elevation of the issue of aesthetic design from its current standing at the cellars of hci research.” (tractinsky, katz & ikar, : ) in this debate what seems to miss is the voice of visual and interface designers. human-computer interaction experts, usability experts, user experience designers, cognitive psychologists have been participating and involved in the evolution of the last years of web and applications evolutions when designers keep silently doing their jobs. despite the first generation of ui designer has been deeply committed to finding a new expressive way to let people interact inside the graphical user interfaces digital ecosystem is difficult to recognize a theoretic contribution and a strong cultural evolution beyond the trends. figure . an entry of wikipedia – the history of ugliness by umberto eco – visualized in the standard mode, on the left, and presented by wikivand®, a browser add-on, aimed to improve the visual aesthetic and interface performance f the free encyclopedia, on the right. . from metaphors to flatness as happened to many design and technologies innovation – moreover in immaterial field – when introduced in the mass market, also the operative systems or software have adopted a mimetic approach to existing material references and/or physical patterns already familiar to the users. even for early adopter – therefore people susceptible and motivated to learn the new mindset of interaction according to the diffusion of innovation theory by rogers ( ) – the experience should s d ow nl oa de d by [ . . . ] a t : s ep te m be r beautiful interfaces. from user experience to user interface design. be supported by a recognizable mental model based on the memories and previous interactions with similar artifact already embedded in people mind. . gui: the visual rhetoric of metaphors the first operating system of the apple based on a graphical interface – launched in – reproduced the office environment to simulate everyday interaction such as archiving documents – folders and files – throwing stuff and garbage away – the bucket – moving object on the tables etc. all these activities are dissimulated in the desktop metaphor designed by susan kare in - and shaped according to the real world. kare has a fine-arts background that mixed with the ideas of steve jobs on good typography give birth to an original digital aesthetic. minimalism, essentiality, white space are the guiding rules of the visual composition and rhythm of the lay-out completed with smart, basic and user-friendly icons and a clear and elegant font. the careful modulation of pixels in their essential composition creates a colorful and expressive language just using black and white and grayscale. elefont, chicago, monaco, and geneva were specifically designed to guarantee a pleasant readability, high legibility and aesthetic quality similar to the analogical typography although still rendered without the anti- aliasing correction. with the revolution of the internet in , the metaphorical approach and visual language have been extended to website and new visual design patterns have been established according to two different perspectives on page design for the net. one first attempt to create a specific iconography for the web is due to the effort of david siegel ( ). the inventor of the transparent dot and the workaround of table grid used to create visual layout mixed both his editorial and typographical culture and his coding and markup knowledge. the result was an almost original aesthetic able to balance the interactive components – specific of the medium a limited by the poor expressive control of the html, the markup language used to compile the semantic structure and content – rapidly become a standard de facto. the visual metaphor and allegories try to connect the visual world with the material of physical elements – papers, d bottoms, shaded boxes, brick walls etc. – were progressively dismissed and a new language of web design try to give voice to the issues, peculiarities, and potentialities of the new-media. the first generation of web design were artist, pioneers, and practitioners at the same time: mike china, todd purgason, amy franceschini, niko stumpo, joshua davis, jugo nakamura, brendan dawes, irene chan are some of the protagonists involved in the on line art gallery the remedy project published since or cited in new masters of flash (bauman & davis, ) as flash designer and innovators. many of this protagonist were keen to mould technologies – although limits s d ow nl oa de d by [ . . . ] a t : s ep te m be r letizia bollini and inadequate – as a design tool able to shape a new visual culture, an interactive and hypertextual language and a multimodal aesthetic. figure . pictures of the remedi project artworks: munkowitz and niko stumpo: football-themed interactive piece (on the left, available at gmuk.com); squid soup (unknown artist) interactive artwork based on onomatopoeia and sound (on the right, available at https://ollenga.wordpress.com/category/sketch/) on the other side of the possibilities to approach to interface design jeffrey zeldman proposes a convergent way between the traditional graphical culture of paper works and the respect of technical standards. he contributes with books – taking your talent to the web: making the transition from graphic design to web design published in and designing with web standards ( ) now at its rd edition – a webzine – a list apart – and the web standard project ( - ) to the design debate sustaining and spreading a design approach based on standards. the introduction of css allows the creative and developers community to separate the content and its structures – build with the semantic html – from its presentation: the visual part. this has become a massively adopted way to think and develop interfaces but also it gave rise to a strong expressive approval and an overall flattering of the expressive issue in digital design. this approach flows in the mainstream on which styling and trends of the next decade are rooted. if standards have simplified and improved the web, the user experience and the access to information, on the other hand, they have turned off the original expressive research, oversimplifying in a series of recurring patterns and trends related to the software possibilities the aesthetic of the digital design. figure . davis siegel’s homepage in : the template is realized using html and images simulating typography (right); the css zen garden template launched in by molly e. holzschlag and dave shea based on the user-generated variation in css of the original template html (right) . skeuomorphism: the world mimesis a new beginning of the expressive experimentation is born with the launch of the first iphone at the beginning of . this first generation of mobile os – which was followed by android developed by google and firstly installed on the devices of apples competitor samsung – adopted a digital skeuomorphic strategy to s d ow nl oa de d by [ . . . ] a t : s ep te m be r http://gmuk.com/ https://ollenga.wordpress.com/category/sketch/ beautiful interfaces. from user experience to user interface design. visual design, or a skeuomorphism style “in which certain images and metaphors, like a spiral-bound notebook or stitched leather, are used in software to give people a reassuring real-world reference” as underlined by wroblewski himself ( ). the term skeuomorphism is compound by the greek words skéuos [σκεῦος]: container or tool and morphé [μορφή]: shape, used since to describe a material object and, nowadays, applied to the digital interfaces as already reported by gessler in . if – generally speaking – d effects, materiality, and touch-feeling are the basic design patterns of the representation language of skeuomorph-interfaces, colors, and their conceptual use is directly drawn from the world. elements are rendered through textures and hues or tints which depict explicitly physical objects that are intended to symbolize or, at least, visually synthesize. a leather-bound diary, a ’ s radio microphone, a d compass where the icon that once tapped – one of the gesture to interact with touch interfaces listed by villamore, willis and wroblewski ( ) – launch the applications. the aesthetic seems to come out directly from the visual mimesis with the real world in a sort of revival of the motto form follow function, but in this case, the function is a digital service or features embedded in a mobile device and the semiotic and symbolic referent is a concrete vintage object. . material design: a touch of abstraction the transition to ios in - (wingfield and bilton, ) ends the pioneer phase of the mobile revolution: new generation of devices have been introduced —not only smartphones but also tablet, phablet, wearables and iot— new brands have been raised in the market older player in it and hardware field are missing the wave or definitely disappearing acquired or exhausted being no more able to compete in a new challenging world. this transition phase represents the required time to normalize the first generation approach, preparing the field for experimenting and addressing further exploration to potentiality and specific features of the devices. mobile os and apps design free themselves from realistic patterns and embrace the new language of the so-called flat design. the flat interfaces – bi-dimensional to differentiate from the d effects, s d ow nl oa de d by [ . . . ] a t : s ep te m be r letizia bollini synesthetic, tactile and shades – find a symbolic and minimal way to communicate to users although maintaining an almost clear affordance according to norman affordances and design and bagnara & broadbent studies ( ). figure . skeuomorphic interface in ios (left); flat design in ios (center); the detail of audio recording built-in app interface based on the ‘ s iconography (right) at its very first launch, flat design of ios was mainly concerned with simplification of the whole user, experience, both in the emotional and mental model and in the technical aspects. loosing d and shaded effects, the vintage look and the dark, heavy metaphor referring to the ‘ s object almost unknown to the younger digital natives and millennials generations, immediately give a new perspective. as reported by matt gemmell in a deep-debated and well-documented post “ios is much, much lighter - in the color sense, and consequently also in visual weight. breathable whitespace is everywhere, and is used to unify… the overall impression is of brightness and openness. ios ’s new look is bold, opinionated and readable.” (gemmell, ). so, the new wave of bi-dimensional visual elements, surrounded by a wide amount of white negative space let the chromatic choices speaking loudly, although not always clearly, according to the ui design basics section of the ios human interface guideline released by apple. soon after, google creates and launched a document – material design – in , in which theoretical concepts, principles and practical examples are given and explained to allow pros to better design apps coherent with the whole approach of android development and framework. in this interactive guide the philosophical perspective is declared and discussed to understand the declination of single principles, their use and implementation: it is a declaration of the aesthetic language, rapidly became “the” visual language of contemporary mobile and responsive app and sites. the declared aim of google is to create a visual language that s d ow nl oa de d by [ . . . ] a t : s ep te m be r beautiful interfaces. from user experience to user interface design. “synthesizes the classic principles of good design with the innovation and possibility of technology and science” but the declared material metaphor has a very different interpretation compared to skeuomorphism. it grounds in tactile reality, inspired by study of paper and ink, but “yet open to imagination and magic.” (google, ) but the concept of materiality, in this new context, means multi-layered, tactile, -dimensional, flat, geometrical surfaces barely differentiated by lightning effects and animations. dramatic changes of bold background colors indicate space articulations or subdivisions and cognitive organization of the interface structure. in the absence of more explicit references to patterns or systems already known by the user the visual grammar and the language of graphic design become the conceptual tools to create the new imaginary as declared: in the fifth principle of the nine conceptual premises: “content is bold, graphic, and intentional: bold design creates hierarchy, meaning, and focus. deliberate color choices, edge-to-edge imagery, large-scale typography, and intentional white space create immersion and clarity.” (google, ) in the end, flat firstly and material design next introduces a bold use of colors in a very abstract and connotative way. colors become “unnatural”, saturated, vivid, acid. contrasts are strong and effective and they become one of the main expressive assets of the mobile interface design. . the brutalism manifesto brutalism was born as a reaction to issues of usability, features that have overwritten the expressive instances of design and its own nature. “brutalism” (or “new brutalism”) is a term which has been rattling round architectural schools for over half a century. it refers to a raw form of architecture with characteristics such as rough unfinished surfaces, unusual shapes, solid materials (like concrete), massive forms, and contrasting small features. brutalist websites, like their architectural cousins, are an antidote to the more popular, softer web. we live in an age of emotional web design; where we as interface and experience designers climb over each other to offer users empathy and understanding. where products entice customers in the friendliest, easiest ways possible. colors are inviting, images are polished, the type is smooth and crafted. looking at brutalist websites, adjectives such as these spring to mind: harsh, rough, rugged, uncomfortable, raw, confrontational, cynical. it’s a school of thinking i like; you could argue my own website (which i haven’t changed in a while) has a touch of brutality” (yates, ) s d ow nl oa de d by [ . . . ] a t : s ep te m be r letizia bollini the informal movement was started in by the creative director pascal deville ( ) in his site brutalistwebsites.com where he collects brutal interfaces. figure . lifeactionrevival.org homepage: an example of brutal interface where all the expressive elements are represented: brutal images with default d borders, limited color palette (gray, pale yellow and blue), basic typography (helvetica and times new roman) brutalism is not just a matter of formal aesthetic and visual surfaces, but it represents a deep change in digital design culture. brutalism is more about code, and the graphic expression is a direct consequence of the technological background. raw code and a crude form are the basis of a simple, not optimized – we could say anti-standard – way to write directly and manually the markup structure and decoration. times new roman, courier, arial and few other system fonts are the solely used in a sort of self-limitation and browser-safe revival. “[brutalism] is interesting to me… because it doesn’t necessarily have a defined set of aesthetic signifiers. what defines those signifiers is decided by the platform it’s built on.” says jake tobin in a recent interview echoes by nathaniel smith, of tilde.town: “i designed a brutalist website to show that we can still do wonderful things together on the web without so-called ‘best practices’”. (archement, ) it sounds like a return to an original eldorado of the late ‘ s driven by simple and effective attempt to find a concrete, warm, fuzzy expressive language. yates recalls the good old times when colors were limited by the browsers safe palette and red, blue, gray were enough. images iconography draws to a time and to a language prior to the glossy and trendy world of instagram. verbal language claim for itself a real vocabulary, brutal and free. . conclusions the contemporary evolution of user interface aesthetic seems to follow a parabolic path. starting from the ‘ s the first protagonists attempt to shape technologies, software and code to the s d ow nl oa de d by [ . . . ] a t : s ep te m be r http://brutalistwebsites.com/ http://lifeactionrevival.org/ beautiful interfaces. from user experience to user interface design. expressive issues of visual language. afterward standards, usability paradigms, and patterns have rewritten the priority of design excluding or, at least, limiting formal aspects and perceived pleasantness as negative components of the people experience. nevertheless, a new consciousness is emerging both in the cognitive, user experience studies field and in the new designer's generations. on one hand the theoretical cultural is giving new space to emotional dimension of design and interactive artifact as a value and a contribution to functional aspects and usability issues. on the other digital designers claim for an experimental, personal place to express a new aesthetic and vision. the exploration of a new language shaped by the medium is creating a retrospective- avantgarde an apparent contradiction. the search for roots and rejection of standardization produce an original mix of backward expressive elements and innovative way to use the technology – markup and scripting language – as an alternative vocabulary. the exploration assumes new eyes and perspectives to see the existing context, deny it and rebuilt according to a new sensibility and a new freedom. furthermore, aptic interfaces, environmental interactions, internet of things, smart objects, ubiquitous computing, augmented, virtual reality and the -dimensional evolution of interactive experiences are opening new possibilities to a multimodal and spatial aesthetic involving a multi sensorial-interactions. they could refer to already seen imaginary like the ones proposed in sci-fi and cyber movies – minority reports in primis – or inventing an original universe of sign, symbols and aesthetic values as called for by gabo arora, onu creative director, and virtual reality designer. references arcement, k. ( , may). the hottest trend in web design is making intentionally ugly, difficult sites. the washington post. retrieved november , , from https://www.washingtonpost.com/news/the-intersect/wp/ / / /the-hottest-trend-in-web- design-is-intentionally-ugly-unusable-sites/ bagnara, s. and broadbent, s. ( ). comunicare con artefatti cognitive. in g. anceschi (ed.) il progetto delle interfacce: oggetti colloquiali e protesi virtuali. milano: domus academy bauman, j.; davis, j. et al. ( ). new maters of flash. new york: apress brutalist web site. retrieved november , , from http://brutalistwebsites.com/ iso ( ). ergonomic requirements for office work with visual display terminals. iso - , iso, geneva. retrieved november , , from https://www.iso.org/obp/ui/#iso:std:iso: :- :ed- :v :en deville, p. ( ). http://www.brutalism.com tobin, j. ( ). truly bald. retrieved november , , from http://www.trulybald.com gemmell, m. ( , june). ios . retrieved november , , from http://mattgemmell.com/ios- / gessler, n. ( ). skeuomorphs and cultural algorithms. in proceeding of the th international conference on evolutionary programming vii, pp. - . berlin: springer-verlag google ( ). material design. retrieved november , , from https://www.google.com/design/spec/material-design/introduction.html s d ow nl oa de d by [ . . . ] a t : s ep te m be r https://www.washingtonpost.com/news/the-intersect/wp/ / / /the-hottest-trend-in-web-design-is-intentionally-ugly-unusable-sites/ https://www.washingtonpost.com/news/the-intersect/wp/ / / /the-hottest-trend-in-web-design-is-intentionally-ugly-unusable-sites/ http://brutalistwebsites.com/ https://www.iso.org/obp/ui/#iso:std:iso: :- :ed- :v :en https://www.iso.org/obp/ui/#iso:std:iso: :- :ed- :v :en http://www.brutalism.com/ http://www.trulybald.com/ http://mattgemmell.com/ios- / https://www.google.com/design/spec/material-design/introduction.html letizia bollini kurosu, m., & kashimura, k. ( , may). apparent usability vs. inherent usability: experimental analysis on the determinants of the apparent usability. in conference companion on human factors in computing systems (pp. - ). acm. lavie, t., & tractinsky, n. ( ). assessing dimensions of perceived visual aesthetics of web sites. international journal of human-computer studies, ( ), - . linghammar, f. ( ). usability and aesthetics: is beautiful more usable. institutionen för datavetenskap , . , p. nielsen, j .(s.d.) useit.com [the site is no more online, but some pics are available in the web archive. http://www.thewebarchive.org/ temporary in maintenance mode]. nielsen, j. ( ). web usability. milano: apogeo editore. nielsen, j., tahir, m., & tahir, m. ( ). homepage usability: websites deconstructed (vol. ). san francisco: new riders norman, d. ( ). emotion & design: attractive things work better. interactions, ( ), - . norman, d. ( ). emotional design: why we love (or hate) everyday things. basic book norman, d. (s.d.) affordances and design. retrieved november , , from http://www.jnd.org/dn.mss/affordances_and.html quan, y., & lee, d. ( ). principles of text organization and aesthetics in cultural interfaces. adada . , - rogers, e. m. ( ). diffusion of innovation. ( st ed.), free press of glencoe oclc siegel, d. ( ). killer web site. londra: macmillan tractinsky, n., katz, a. s., & ikar, d. ( ). what is beautiful is usable. interacting with computers, ( ), - . yates, i. ( , may). it’s tough out there: a look at brutalism in web design. retrieved november , , from https://webdesign.tutsplus.com/articles/its-tough-out-there-a-look-at- brutalism-in-web-design--cms- veen, j. ( ). the art & science of web design. san francisco: new riders villamore, c.; willis, d. and wroblewski, l. ( , april, ). touch gesture reference guide. retrieved november , , from from http://www.lukew.com/ff/entry.asp? vitruvio, m. p. ( ). de architectura. vol i, wingfield, n. and bilton, n. ( , october). apple shake-up could lead to design shift. the new york times. retrieved april , , from http://nyti.ms/qvp vc wroblewski, l. ( ). mobile first. san francisco: a book apart zeldman, j.(s.d.). a list apart. retrieved november , , from http://www.alistapart.com [this version of the site is more online, but some pics are available in the web archive. http://www.thewebarchive.org/ temporary in maintenance mode] zeldman, j. ( ). taking your talent to the web: making the transition from graphic design to web design. san francisco: new riders publishing zeldman, j. ( ). designing with the web standards. san francisco: new riders publishing s d ow nl oa de d by [ . . . ] a t : s ep te m be r http://useit.com/ http://www.thewebarchive.org/ http://www.jnd.org/dn.mss/affordances_and.html https://webdesign.tutsplus.com/articles/its-tough-out-there-a-look-at-brutalism-in-web-design--cms- https://webdesign.tutsplus.com/articles/its-tough-out-there-a-look-at-brutalism-in-web-design--cms- http://www.lukew.com/ff/entry.asp? http://nyti.ms/qvp vc http://alistapart.com/ http://www.thewebarchive.org/ beautiful interfaces. from user experience to user interface design. about the authors: letizia bollini, assistant professor of visual and interface design. she earned is ph.d. from the politecnico di milano. she is an architect, a researcher, a designer focused on visual and multimodal interfaces, cultural and digital heritage, and spatial representation. s d ow nl oa de d by [ . . . ] a t : s ep te m be r a beautiful prize nature materials | vol | december | www.nature.com/naturematerials editorial dan shechtman’s reaction after seeing the seemingly impossible electron diffraction pattern emerging from an alloy of aluminium and manganese was one of surprise and scepticism. it was only after excluding, through further experiments, the possible artefacts that could have produced such a result that he convinced himself that the ten-fold symmetry pattern he had observed corresponded to a compound with rotational but not translational symmetry , hence ordered but aperiodic. it was april , and the belief that crystals must be periodic was so strong at the time that shechtman’s results were met with outrage and criticism, even after publication, and not least by an authority such as linus pauling . it was only shechtman’s perseverance in challenging the established knowledge, even at the risk of derision and isolation, that would eventually lead to wide recognition, and finally to the award of the nobel prize in chemistry. a great part of the fascination for quasicrystals — so defined by levine and steinhardt in a paper published only weeks after shechtman’s — is owed to their unusual and mesmerizing, though mathematically well defined, atomic structure. a structure that, as shown by lu and steinhardt has similarities with the decoration patterns using girih tiles made by islamic artists several centuries ago. some of these patterns can still be admired, for example, in the mausoleum of oljeitu in soltaniyeh in iran (pictured); in the case of the darb-i imam shrine (also in iran) they resemble a proper quasicrystalline structure in two dimensions. from a theoretical perspective, the possibility of tiling up a two-dimensional space with a five- or ten-fold rotational symmetry had been challenging mathematicians for a long time, until it was elegantly solved by roger penrose in the s . these studies proved essential in determining the type of arrangements that atoms assume in a quasicrystal, although it is fair to say that the possibility that such patterns could occur in real crystals as energetically favoured phases was initially surprising. the aperiodic structure of quasicrystalline materials has enormous consequences for their electronic, thermal and mechanical properties. most quasicrystals are composed of metallic elements, but the electrical conductivity is not metallic at all, and increases with temperature in a similar fashion to that of semiconducting crystals. the aperiodicity also leads to very low thermal conductivity, as well as unique hardness and low friction. undoubtedly, the interest in quasicrystals in the past three decades has also been fuelled by the prospects of technological applications. low friction could be applied to micro- and nanomechanical systems whereas low thermal conductivity could lead to efficient thermoelectric devices and thermal barriers. other applications such as light absorption and sensing, catalysis, hydrogen storage and even cookware have been pursued . it is fair to say, however, that despite some isolated examples — like the production of non-stick pans that have a quasicrystalline coating — quasicrystals have hardly changed our day-to-day life. whether it is appropriate to award the nobel prize to a discovery with potential technological applications before such applications are successfully realized is debatable. but it is hard to disagree with the fact that the discovery of materials that should not exist, that have provided a completely new perspective on a whole subject area, and that have raised the interest and excitement of a wide range of multidisciplinary scientists, deserves such important recognition. this is precisely the case for quasicrystals. more widespread applications may come. but as elegantly argued by the quasicrystals expert jean-marie dubois in his book useful quasicrystals, the value of these materials is not necessarily to be sought in their relevance for technology ; instead, we should consider that they “have revolutionized our description of solid matter”. in light of the discovery, the definition of crystal had to be officially changed from a periodic structure to one that produces a discrete diffraction pattern. quasicrystals also provide a unique playground for scientists of different backgrounds to synthesize new compounds and to understand their very unusual properties. at times when too much emphasis is put on technological relevance of scientific work at the expense of scientific curiosity, the nobel prize for a discovery that has had a primarily fundamental scientific impact is most welcomed. thus, our most sincere congratulations go to dan shechtman, in recognition of his discovery and of his struggle to affirm his ideas against the scientific establishment. ❐ references . shechtman, d., blech, i., gratias, d., cahn, j. w., phys. rev. lett. , – ( ). . pauling, l., nature , – ( ). . levine, d., steinhardt, p. j., phys rev. lett. , – ( ). . lu, p. j., steinhardt, p. j., science , – ( ). . penrose, r., bull. inst. math. applic. , – ( ). . dubois, j. m., useful quasicrystals (world scientific, ). the nobel prize in chemistry awarded for the discovery of quasicrystals recognizes a breakthrough that has fundamental scientific consequences. a beautiful prize pe te r j. lu © macmillan publishers limited. all rights reserved a beautiful prize references tubeach.dvi � �� !�� "�� #�� $%�� &�� !� � '� �� &�� !� �� (� $��(� �� !�(�� )�� *�� !�(�� +,-./ - � � '�! �� !� � �� " � �� #� �� $ �� % �&� '�� !� �$�� (�� % �� % �)� �� *+, �� - ��% �.� /�� - �� $�� $�� !� �� "�##$� �� %&�'%� �'( �(�%�#&�' � ��%� �� '� �� '� �� $ �� (� �� (�� *�� ! �� '" � �� *�� ( �� ( �� *� �� !�! 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message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ microsoft word - beauty constructs for mp players.doc codesign – intetrnational journal of cocreation and design and the arts, vol ( ): - , . beauty constructs for mp players ali al-azzawi digital world research centre & department of psychology university of surrey, guildford, surrey gu xh, u.k. a.al-azzawi@surrey.ac.uk david frohlich digital world research centre university of surrey, guildford, surrey gu xh, u.k. d.frohlich@surrey.ac.uk margaret wilson department of psychology university of surrey, guildford, surrey gu xh, u.k. m.wilson@surrey.ac.uk abstract this paper contributes to the current debate about the nature of beauty and aesthetics as they apply to interactive products. current disagreement centres around the question of whether beauty should be viewed as a continuous property of objects or as a rare emotional response to object encounters (hassenzahl , frohlich ). here we develop a new perspective of beauty as a complex psychological construct, subject to competing influences from visible object properties such as shape and colour, and invisible object associations such as perceived ease of use and brand. we introduce a new methodology for examining such constructs based on a card sorting procedure, and use it to show how participants think about the beauty of mp players. one major finding is that participants tended to evaluate the players holistically, applying similar categorisations to free sorts, beauty sorts and preference sorts. this involved a common polarisation between modern and post-modern forms as they have been found to apply to architectural styles (wilson ). introduction the field of human computer interaction (hci) was initially established to examine the relationship between people and computers, at a time when getting the computer to do what you wanted was a major challenge (e.g. card, moran & newell ). considerations of the beauty of a computer did not arise in this era, which was more dominated by considerations of error, incomprehension and frustration. things are very different today in a context where the interfaces to personal computers have standardised around a handful of operating systems and common applications, and the design of the computer itself has become a differentiator for consumer sales. computing resources are also assuming a variety of novel forms, as they become embedded in portable physical objects or situated architectural surfaces. this is leading to a merging of human computer interaction with product design and architecture, and a re-framing of questions of aesthetics, pleasure and fun as they apply to interactive experiences (e.g. blythe et al , jordan , mccarthy & wright , norman ). one debate to arise out of these developments is about the nature of beauty and how it relates to digital products. a recent set of discussions have been published in the human computer interaction journal, around a new study by hassenzahl (hci special issue volume ). hassenzahl ( ) undertook a study to examine the beauty of software mp players and its relationship to other attributes such as usability and goodness, using a series of bipolar rating scales and correlations between them. he suggests that perceived beauty is more related to judgements of hedonic identification or self-presentation, than to judgements of usability or other kinds of hedonic stimulation (pleasure). this contradicts previous work which showed that perceptions of beauty affected perceptions of usability, such that ‘what is beautiful is usable’ (tractinsky et al ). irrespective of the particular findings reported, hassenzahl’s paper has sparked a discussion about the nature of beauty in hci and how to measure it. hassenzahl’s view that beauty is a continuous property of an interactive artefact, whose extent can be measured on a simple rating scale, was challenged by frohlich ( ). frohlich observed that beauty has been defined differently in classical philosophy, as a rare all-or-nothing response to an object experienced in a particular context, and may not have been present at all in hassenzahl’s experiment or others’ like it. he recommended studying beauty by collecting stories of its occurrence, wherever it can be found. unfortunately this is not a practicable method that can be applied to a specific product’s design. it closes off a form of affective engineering to assess the impact of design alternatives on related judgements or experiences of beauty. if beauty really is so rare, how can people compare the beauty of individual items and what are they really thinking about when they do this? in this paper we address this question and debate by introducing a new methodology for studying beauty as a multi-faceted psychological construct. we argue that different “kinds of beauty” may be perceived in relation to different product options based on comparisons between them, and that these perceptions co-exist alongside other constructs, including overall preference. we also examine the relationship between preference and beauty. there is wide agreement to the notion that in order to arrive at more meaningful theory and understanding, it is important to elicit data in a clean way without researcher influence. we have adopted the facet theory approach (canter , shye et al ), which has had much success in other areas of psychology and aesthetics (wilson & ). wilson’s previous work showed insight into the relationship between architecture style and preference. this approach is based upon gathering data without any assumptions regarding individual users’ constructs, unlike other methods where the constructs are predefined such as semantic differential scale (osgood et al ). our methodology is based on a multiple sorting procedure (msp), a card sorting procedure originally developed to examine people’s conceptual system and to elicit their constructs and categories for a given context (canter et al ). it has been successfully applied to the perception of architectural style in buildings (wilson & canter ), and has become a useful tool in environmental psychology. we apply it here for the first time to the perception of interactive products, and show how it begins to reveal how users themselves define and discuss aesthetic properties. method participants thirty participants volunteered to take part in the study ( males & females, average age = . years (range = )). for the preference data, there were extra participants ( males & females, average age = . years (range = )). each participant was given cards (figure- ) that showed a good quality, colour, life-sized photograph of a hand-held portable mp player. the mp players (appendix a) were picked from the offering that is currently available in the market, and were chosen to be as broad a range as possible. the range of mp players was verified during a pilot study, which showed that there was a good spread in the data. the whole of the session was recorded using a voice recorder for later analysis. the msp looks at the participants’ own relative judgments and concepts in order to investigate their individual perceptions and how they conceptualise beauty in objects. the msp was run in three modes; free-sort, semi-structured sort and structured sort. figure – mp players used in this study. in the free-sort mode, the participants were asked to sort the cards for any criteria (constructs), into any number of piles and with any number of cards into each pile. the participants then attributed labels (categories) to each pile and explained their rationale. codesign – intetrnational journal of cocreation and design and the arts, vol ( ): - , . in the semi-structured mode, the participants were given the sorting criteria (in this case “kinds of beauty”), and then they were asked to sort the cards into any number of piles with any number of cards into each pile. in the structured sort, the participants were given the sorting criteria, in this case “preference”, and the number of piles and the meaning for each pile (in this case it was a -point preference scale). however, there were no restrictions on the number of cards per pile. results sorting constructs the multiple sorting procedure (msp) was used for this part of the data collection. the participants were given the cards with the instruction to sort them into any number of piles for any reasons or criteria they wanted (free-sort). all participants were given the following verbal instruction (based on that given by canter et al. ( )): “i am carrying out a study on how users experience technology. so i am asking a number of people to look at the photographs of mp players (the photographs are : scale) and to sort them into groups in such a way that all the mp players in each group are similar to each other in some important way and different from those in the other groups. you can have as many groups as you like, and have as many mp players in each group as you like. it is your views that count. when you have carried out the sorting i would like you to tell me the reasons for your sorting, and what the mp players in each group have in common. assume that they all have similar specifications.” once sorted, the item codes were recorded from each photograph for each group. the participants were then asked to clarify the criterion (construct) of the sort, and to give a description for each of the groups within this criterion. on the more subjective sorts, such as “easy to use”, the participants were asked to elaborate on the choices made. open questions were used such as “what about these items make them easy to use?” participants performed as many free sorts as they felt able to find new sorting criteria. in order to have a systematic way of collating the constructs into structured data that can be analysed, a set of rules were devised. for a construct such as “controls” the rules will be the following: - count all references to “controls”. - if a participant used “controls”, as a sorting criteria, then the count for references to “controls” is incremented by one. - if a participant sorted for “controls” and “size” at the same time, for example the participant may say “this pile is big with small controls, and this pile is small with round controls”, then the count for references to “controls” is incremented by one, and the count for references to “size” is incremented by one. - once all the references are counted, for all the participants, they are aggregated into a more concise data set. for example, if there was one count for “shape of controls” and one count for “number of controls”, then they are aggregated under two counts for “controls”. in summary, the counting was done for any time a participant referenced that particular construct (as a sorting criteria) as a way of distinguishing between mp players. all the sorts from the free-sort part of the data collection were analysed to assess the “constructs” that the participants had during the visual interaction. this data (table- ) show a mixture of objective and subjective constructs. the “cross-linking” construct refers to situations where the participant may have described the sorting criteria (the construct) in one way, and the individual categories within the construct, were described in another way. for example, participant a- used the construct “sport” and the criteria within the sort were; light and heavy. another example was “average comfortable-to-hold size”, by participant a- . another example was with participant a- , where he distinguished a sort on “shape & display” and also said that a large display meant better quality. also, participant a- used the construct of “size” and linked it to “user friendly”. this suggests that size is related to usability somehow. there were some constructs that seem to be concerned with functionality or specifications, but actually were more concerned with convenience. for example the “battery” construct was explained by participant a- as “mp players that show battery life”. several participants saw item- as “just a watch” or “the watch”, and even put it in a pile on its own, while others were happy to see it as an mp player. no. construct references screen size controls shape colour aesthetics brand design functions usability convenience buy price watch headphones cross-linking ipod orientation construction quality sport age gender weight texture battery table – constructs used in all the free-sorts by all participants. the free-sort data were analysed using multidimensional scalogram analysis (msa) (zvulun , wilson ). the msa program provides a plot of all the mp players as points in geometric space, such that the more frequently two items are placed in the same category the closer together they are in the plot. therefore, irrespective of the overt reason that the participant chose for placing the item in that category, it would be reasonable to assume that there is a physically visible property that helped the participants concur, knowingly or otherwise. even though the instructions were clear regarding the functional specifications (to ignore them), many participants still involved the specifications in the sorting task. participant a- actually said that it would “not make sense” to sort them without including what he could assume, or remember about the functional specifications of the items he was seeing. what was also interesting about this particular session with a- is that he insisted that he was making logical judgements about the specifications throughout most of the session, and he chose item number as his favourite, with reasons such as “well designed”, “good size” and “solid state” [referring to the technology type]. however, when asked; “would you still like it if it was green?” the answer was an instant “no!”. participant a- also had reservation about not including specifications into his sorts, and in fact did included specifications and function on several occasions. there were also participants who were not interested in any specifications and said that they would only wanted to know “how many songs can it hold” and “as long as it looks good”. the msa plots were divided into regions and were given labels that are an interpretation by the researcher. the interpretations were derived from the aggregate of the constructs that the participants gave for the individual items, which consequently appear in the regions. figure – msa of first sort for all participants. the msa (figure- ) shows the data obtained in the first sort (of the free-sorts) of all participants. these data reflect the first impressions experienced by the participants. although there are four regions, they can be grouped into two groups; simple (standard and horizontal) and non-simple (curved and other) designs. codesign – intetrnational journal of cocreation and design and the arts, vol ( ): - , . kinds of beauty this part of the data was used to gain better insight into how the participants think about beauty, and to find out about what aspects of the mp player reflect the sense of beauty. the participants were asked to perform a msp in a semi-structured sorting mode. the participants were asked to sort the cards into any number of piles for the criterion of “kinds or types of beauty”. all participants were given the following verbal instruction: “please sort the photographs for the criteria of beauty into any number of groups. sort them in such a way to show how they differ in ‘kinds of beauty’ or ‘types of beauty’.” at the end of the sort, the items’ codes were recorded. once the sorting was done, the participants were asked to explain the rationale and meanings behind their choices and an unstructured discussion was allowed to take place. the “kinds of beauty” sort showed a very large range of ways of describing beauty categories and attributes. this data also showed common beauty categories along with idiosyncratic ones that only appear once amongst all the participants. although most participants were able to perform this sorting task easily and responding with such comments as “sure, i see what you mean” or getting straight into the task, a few did see it as a matter of scale, and would sort the photographs in a scalar manner; least beautiful (or ugly), to most beautiful. participant a- chose “the watch” (player number ) as his favourite, and remarked that it was very “james bond” and was visibly excited about the possibility of using it. i met this participant the very next day, and he said that he spent the night hunting on the world wide web for a place to buy the watch, and was interested to know if i would recommend any stores. during his “kinds of beauty” sort, this participant categorised this mp player as having “technological beauty”. there was no correlation between preference and the beauty category chosen by the participant. participant a- pointed out an interesting “kind of beauty”. when she sorted for “kinds of beauty”, she used the following categories: average smooth rounded colourful ugly holiday the category of “holiday” was attributed to one mp player only, number . when asked about what that meant, she said that the picture depicted on the screen of the player screen [showing a holiday scene] made her like the player, and it reminds her of a nice holiday. she subsequently gave the player the highest preference score of . no. category ref. no. category ref. beautiful compact colour complicated ugly conventional average cost nice cute shape dinky attractive dull functional elegant simple eye-catching sleek fiddly bulky form gender geek original like size ok technological pleasing boring regular design shiny different sport effort stereotype futuristic symmetry misc. streamlined practical striking quirky tacky smooth the mark stylish traditional texture trendy aesthetic unknown angular unusual classic weight clutter total table – this table shows the categories used in the “kinds of beauty” sorts by all participants, and the number of times they are referenced. (ref. = references). the msa shown in figure- shows four main regions that show different “kinds of beauty”. this is consistent with the general discussions with the participants where there were regular references to “curved” and “shapely” shapes, and also “very standard”, “average”, “stereotypical” and “mp player look”. the items in the “functional” group were also given names such as “tough”, “dull”, “male” and “old”. figure – msa of “kinds of beauty” sort for all participants. as with the msa for the first-sort (figure- ), the msa for the “kinds of beauty” sort (figure- ) could be grouped into two main groups; simple (functional and standard), and non-simple (odd and curved). this would suggest a similarity between “beauty” and the first-impression that users have when sorting photographs of mp players. preference sort the participants were finally asked to sort the cards according to “preference”. all participants were given the following verbal instruction: “please sort the photographs for personal preference. sort them into groups, where “ ” is the most preferred, and “ ” is the least preferred.” just before the participants were allowed to sort the photographs, seven numbered cards (with the numbers to printed on them) were spread evenly across the sorting surface. the intention was to provide a visual cue for the participants and ensure they followed the instructions correctly. once the sorting was completed, the items’ codes were recorded for each pile. the participants were asked to explain the rationale behind their choices and an unstructured discussion was allowed to take place. a mean preference was calculated for each mp player and the data is shown in figure- . mean preference . . . . . . . mp -player code m ea n p re fe re nc e figure – chart showing the mean preference for each item (averaged for all participants). the preference data were analysed using smallest space analysis (ssa). ssa is a nonmetric mds (multidimensional scaling) technique that represents variables as points in geometric space. the distance between the points is inversely proportional to the rank order of the associations between the variable. this means that the closer the points the more associated the variables they represent. the structured preference sorting tasks allow insight on how the structure of physical properties underlying preference. as can be seen in d-ssa plot (figure & ), there is a colour gradient across the plot, and there is also a screen colour variation (blue/dark screen at the bottom, and lighter/colourful screen at the top). there is also an orientation variation (landscape vs. portrait) and also a curved/small band that skirts the outside of the plot on the right. the meaning of the plot is that participants who preferred a particular item, are also likely to prefer another item closest to it, and unlikely to prefer an item far away from it, especially if it is on the opposite side of the plot. codesign – intetrnational journal of cocreation and design and the arts, vol ( ): - , . figure – d-ssa of preference sort for all participants (guttman-lingoes' coefficient of alienation = . in iterations). the guttman-lingoes' coefficient of alienation for the d-ssa plot (figure- ) was . . shye (shye , pp ) discusses the value of using this coefficient, and shows that it is best used as a discretionary guide, and ultimately the data is useful if trends are visible and interpretable, which they are in this data set. there were several examples of the participants making gestures with their hands as they were viewing the photographs, as though they were testing something. when asked to elaborate on this behaviour, they would say that they were “trying it out”. participant a- also went on to say “i am trying to see if i can control the buttons in the right way”. conversely, participant a- said that he “could not imagine having it [item ] on my wrist”, while gesturing on his wrist. he said “i am intrigued, i tried to imagine having it on my wrist”. when asked “you tried to imagine it?” he said “yes, i have tried, and i just can’t!” participant a- was gesturing with his hands as he saw one of the photographs, and when asked about his actions, he said that he “was trying it out”. figure – schematic diagram of ssa of preference showing general mp player colour distribution, shape, orientation and screen colour. figure – d-ssa of preference sort for all participants showing mean preference. the size of the circle is directly proportional to the mean preference for each mp player. the positions of the items match the positions shown in figure- . the solid dark-blue circles form a band across the middle of the plot. these circles represent mp players that have a mean preference in the lower half ( out of items) of the population, i.e. they represent the half that has the least preference. participant a- , referring to the time when he was shopping for his own mp player, said “it spoke to me [item ]…you think about using it, about situations where you would use it…i fly to america…i thought about taking it out on the plane…people might be curious [watching me]…i could see myself using it…i can see it fitting my life…i literally positioned myself using it [on the plane]”. this demonstrates a strategy that some participants use in order to verify a “fit”, and ultimately influences their decision on preference. the results of the ssa of preference ratings demonstrate that there appear to be two groups of mp players that are preferred by this group of participants. according to the principles of ssa, it is likely that those who prefer the players to the top left of the ssa plot (figure & ) will have rated as less preferred the group of mp players toward the bottom right of the plot and vice versa. references to the actual players represented in these groups shows that the first group are primarily rectangular and do not tend to use colours beyond black, white and sliver. in contrast, the other group are primarily curved and unusual shapes that use fun imagery and some colour. interestingly, this corresponds to the distinction between modernism and post-modernism found to underlie architectural preference in wilson’s ( ) study. discussion this group of data collection methods, as a whole, include several opportunities for discovering salient aspects of the experience with mp players, such as past experiences that influence the current experience, as well as environmental and social factors that precede the specific interaction with the technology items. a key part of this approach is that the criteria that were elicited during the msp provided a “tailored” framework for the discussion of the aesthetic constructs that were relevant to the participant and therefore allowed the participant to be fully engaged and able to reveal more of their salient experiences. this study concentrated on the visual interaction with mp players, and participants were not given the opportunity to handle the devices. this could be seen as missing a vital component of interaction. however, we argue that this level of interaction is important in its own right, and the fact that the participant were engaged and were able to relate to the products, shows this validity. essentially, this interaction is similar to the interaction via any visual medium such as paper or on-line catalogues or window shopping. when the participants sorted the photographs, they could only see the objective aspects, and were overlaying their own interpretations and meanings on what they saw. the results of the free-sort msa (figure- ) showed that there are distinct objective parameters that were perceived by the participants, such as “rectangular” (portrait and landscape orientations), “curved” and “irregular” shapes. the constructs described in table- show a richer range than the msa, which shows that the simple, user- defined and objective, constructs such as colour, shape and size, are ultimately translated to constructs that are more personal and subjective such as “attractiveness”, “beauty” and “easy-of-use” and they help create the initial impression made by the object. it is ultimately the relationship between the participant and the objective constructs that create the more subjective ones, and therefore concepts such as beauty lie within these relationships. participants also tended to link personal values to objective attributes such as “clean”, “easy to use”, “well designed”, “simple” and “fun”. an example of how an experiential response can be triggered by an objective aspect of an mp player, was the example of the “holiday” construct, that was triggered by the screen showing a holiday scene and ultimately lead to a high preference rating. the data also showed definitions of beauty ranging from “symmetry”, “sleek” and “simple” to “trendy”, “striking” and “eye- catching”. beauty was also defined as “technological”, “futuristic” and “classic”. these definitions are anchored to objective parameters, as seen in the groups in the msa plots. the regions shown in figures & , show a consistent grouping of the individual mp players, and both figures show an almost identical split between simple designs and non-simple designs. this is echoed in the preference plots (figures & ) where there seems to be two distinct groups of preferences; modern and post-modern. although the data show that there is a degree of consensus (figure- ) of preferences of the mp players, it is also clear that there are individual variations. it is therefore difficult to conclude a simple relationship between individual preference and mean- preferences, for example, item number , which is a watch that is also an mp player. most participants hated it, and said so unreservedly, while two participants were totally enamoured by the item, to the extent that one of them subsequently searched the internet to find the watch in order to buy it. codesign – intetrnational journal of cocreation and design and the arts, vol ( ): - , . table- shows the distribution of construct counts for “kinds of beauty”. power distributions occur naturally and they are given different names in different disciplines e.g. zipf and pareto distributions (zipf ). this phenomenon is also referred to as “the long tail”. there are also many theories on why this is a general phenomenon in nature (newman ), and the question of “why this happens specifically in beauty”, could be a research project in its own right. the large number of beauty categories shows a large variety of different ways of defining beauty, although there are a few categories that are most popular. however, the smaller number of objective constructs shows a limited number of perceived objective parameters. a few non-owners have owned an mp player in the past, or their partner has one, they sometimes use. this makes the category of “owner” ambiguous in its meaning. we also saw several examples where there was a link between the preferred mp and the “exposure” the participant had to that particular device, in the physical sense as well as the advertising media sense. this is consistent with the mere- exposure effect (zajonc ), and participants readily admitted that they know about it, and their friends have it, therefore they prefer it. the notion of preference has only had little exposure in the general debate where the “halo effect” was cited as a major factor (de angeli & sutcliffe ), where users are likely to have enhanced usability and preference towards devices that are attractive. preference seems to be influenced by “trials”. some participants were “trying out” the mp players to see how they could be used, how they would fit into their lives and the way they would go about using them in different scenarios. these scenarios included social occasions as well as usability and convenience situations. although participants were explicitly asked to ignore technical specifications, most of them found it very difficult to separate beauty and preference from specifications. this could be linked with the cross- linking that was apparent in many discussions and sorting criteria, were objective attributes were given meanings that were subjective in nature. frohlich ( ) discussed consistencies within groups that agree about examples of beauty, and he also discussed individual idiosyncratic examples. our data concurs with this view. however, we also show that beauty can also be a “kind” of beauty, and these kinds are borne of the way participants relate to the items under investigation. so, we conclude that beauty is not a scalar quantity along some arbitrary dimension, and neither a singular emotional response, but a result of complex relationships between the object itself and how an individual relates to it. of course, it is important to note that such relationships could well be socially constructed (bull ). for example, the attraction towards the ipod is not just about the device and its physical attributes, but also about membership of the ipod community. the msp data collection method, along with the msa technique, has provided a useful insight into the users’ conceptualisations of their interaction with mp players, and this methodology could be extended to other artefacts and contexts of interaction. overall, these data show that the facet theory approach provides a useful set of techniques that can help us further understand beauty within technological artefacts. conclusion we believe that beauty is a function of the relationships between many components, tangible and intangible. we also believe that beauty is linked to a sense of wonderment and surprise, and the intensity of beauty, as a response, begins to wane when expectations and promises are not met, and therefore can be fragile. however, there was evidence that beauty in mp players follows that of buildings, as demonstrated by wilson ( ) who showed a basic split; modern and post-modern. there was no evidence of a direct relationship between preference and beauty, and we saw examples where preferences can shift in an instant and are linked to mundane factors such as specifications, convenience and cost. participants also seemed to make holistic judgements about the fit of the individual products to their lifestyle and image. further investigation into the notion of preference is required along with studies that explore how physical interactions influence beauty and preference. work is also required in correlating these finding with individual differences between users, in order to obtain a usable model or guidelines that can be used by designers who wish to provide more pleasurable products for users. appendices appendix – a: mp players used in the study code brand model creative zen vision creative zen vision creative zen sleek creative zen micro maxfield diamond creative muvo sport c creative muvo tx creative muvo slim sony nw-a sony nw-e sony nw-e sony nw-e sony nw-e sony nw-hd iriver h iriver h iriver t iriver ifp- apple ipod shuffle apple ipod apple ipod nano philips psa philips hdd nike + philips psa mpeye hts- mpeye hts- yepp yp- sanyo hdp-m sandisk sansa m pebble pebble rio carbon ce xonix mp- elio m dnt star -ir odys mp -s references . blythe, m.a., overbeeke, k., monk, a.f. and wright, p.c., funology: from usability to enjoyment, (kluwer academic publishers: dordrecht, boston, london). . bull m., no dead air! the ipod and the culture of mobile listening. leisure studies, vol. , no. . pp. - . . canter, d. (ed.), facet theory: approaches to social research, (springer verlag: new york). . canter d., brown j. & groat l., a multiple sorting procedure. in brenner, m., brown j. & canter d. (eds), the research interview: uses and approaches, (academic press: london). . card, s., moran, t., & newell, a., the psychology of human-computer interaction. (lawrence erlbaum associates: hillsdale, nj). . de angeli a., sutcliffe a., & hartmann j., interaction, usability and aesthetics: what influences users' preferences? proceedings of the th acm conference on designing interactive systems, pp. - , (acm press: ny, usa). . frohlich d.m., beauty as a design prize, human- computer interaction. volume , pp. - . . hassenzahl m., the interplay of beauty, goodness, and usability in interactive products, human- computer interactions. volume , pp. - . . jordan p., designing pleasurable products. (taylor & francis: london). . mccarthy j. and wright p., technology as experience. (mit press: cambridge, ma, usa). . newman m., the power of design, nature , - . . norman d. emotional design: why we love (or hate) everyday things, (new york: basic books). . norman d., introduction to this special section on beauty, goodness, and usability, human- computer interactions. volume , pp. - . . osgood c. e., suci g j & tannenbaum p. h., the measurement of meaning, (illinois university press: urbana, il). . shye, s., elizur, d. & hoffman, m., introduction to facet theory, (sage: thousand oaks). . tractinsky, n., shoval-katz, a., ikar, d., what is beautiful is usable, interacting with computers , - . . wilson m. a. and canter d., the development of central concepts during professional education: an example of a multivariate model of the concept of architectural style, applied psychology: an international review. volume ( ), pp. - . . wilson m., structuring qualitative data: multidimensional scalogram analysis. in breakwell g., hammond s. & fife-shaw c. (eds), research methods in psychology. (sage publications: london). . wilson m., the socialization of architectural preferences, journal of environmental psychology, : - . . zajonc r., feeling & thinking: preferences need no inferences, american psychologist : - . zipf, g. k., human behavior and the principle of least effort, (addison-wesley: reading). . zvulun e., multidimensional scalogram analysis: the method and its application. in shye s. (ed.), theory construction and data analysis in the behavioural science, (jossey-bass: san francisco). wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ electrophysiology meets printed electronics: the beginning of a beautiful friendship | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /fnins. . corpus id: electrophysiology meets printed electronics: the beginning of a beautiful friendship @article{inzelberg electrophysiologymp, title={electrophysiology meets printed electronics: the beginning of a beautiful friendship}, author={l. inzelberg and y. hanein}, journal={frontiers in neuroscience}, year={ }, volume={ } } l. inzelberg, y. hanein published computer science, medicine frontiers in neuroscience electroencephalography (eeg) and surface electromyography (semg) are notoriously cumbersome technologies. a typical setup may involve bulky electrodes, dangling wires, and a large amplifier unit. adapting these technologies to numerous applications has been accordingly fairly limited. thanks to the availability of printed electronics, it is now possible to effectively simplify these techniques. elegant electrode arrays with unprecedented performances can be readily produced, eliminating the… expand view on pubmed frontiersin.org save to library create alert cite launch research feed share this paper citationsbackground citations view all figures and topics from this paper figure figure electrode surface electromyography neuroscience discipline cross-talk electrophysiology (science) brainwave biofeedback citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency wearable and comfortable e-textile headband for long-term acquisition of forehead eeg signals manuel reis carneiro, aníbal t. de almeida, m. tavakoli computer science ieee sensors journal save alert research feed electroantennography measurement by printed electronics electrode naoki yamada, s. shigaki, + authors k. hosoda computer science ieee/sice international symposium on system integration (sii) save alert research feed a d printed device for low cost neural stimulation in mice t. morrison, elana sefton, melissa marquez-chin, m. popovic, c. morshead, h. naguib computer science, medicine front. neurosci. view excerpt, cites background save alert research feed critical appraisal of surface electromyography (semg) as a taught subject and clinical tool in medicine and kinesiology v. medved, s. medved, i. kovač medicine frontiers in neurology save alert research feed the influence of screen-printing parameters on properties of conductive layers for application in biomedical electrodes l. kołodziej, s. ostrowski, a. maciejewski, m. jakubowska, g. wróblewski materials science save alert research feed biosensing in dermal interstitial fluid using microneedle based electrochemical devices julia madden, c. o'mahony, m. thompson, alan o’riordan, p. galvin materials science save alert research feed references showing - of references sort byrelevance most influenced papers recency ultraconformable temporary tattoo electrodes for electrophysiology laura m. ferrari, s. sudha, + authors f. greco materials science, medicine advanced science pdf view excerpts, references background save alert research feed temporary-tattoo for long-term high fidelity biopotential recordings lilach bareket, l. inzelberg, + authors y. hanein materials science, medicine scientific reports pdf view excerpts, references background and methods save alert research feed inkjet printed flexible electrodes for surface electromyography r. scalisi, m. paleari, + authors a. chiolerio materials science view excerpts, references methods and background save alert research feed comparison of three types of dry electrodes for electroencephalography p. fiedler, j. haueisen, + authors c. fonseca materials science highly influential pdf view excerpts, references background save alert research feed dry eeg electrodes m. a. lopez-gordo, d. s. morillo, francisco pelayo valle engineering, medicine sensors pdf view excerpts, references background save alert research feed novel screen printed electrode set for routine eeg recordings in patients with altered mental status s. myllymaa, p. lepola, + authors katja myllymaa materials science, medicine th annual international conference of the ieee engineering in medicine and biology society (embc) view excerpts, references background and methods save alert research feed new disposable forehead electrode set with excellent signal quality and imaging compatibility s. myllymaa, p. lepola, j. töyräs, t. hukkanen, katja myllymaa medicine journal of neuroscience methods view excerpts, references background and methods save alert research feed home monitoring of sleep with a temporary-tattoo eeg, eog and emg electrode array: a feasibility study. s. shustak, l. inzelberg, + authors y. hanein computer science, medicine journal of neural engineering save alert research feed unobtrusive ambulatory eeg using a smartphone and flexible printed electrodes around the ear s. debener, reiner emkes, m. de vos, m. bleichner medicine scientific reports highly influential pdf view excerpts, references background and methods save alert research feed screen-printed eeg electrode set for emergency use p. lepola, s. myllymaa, + authors katja myllymaa computer science view excerpts, references methods save alert research feed ... ... related papers abstract figures and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue biblioteca di economia e management salta al contenuto principale italiano english form di ricerca cerca biblioteca di economia e management unito.it sezioni la bem presentazione dove siamo orari di apertura accesso norme di comportamento staff organi documenti, regolamenti e privacy statistiche la bem in immagini collezioni libri di testo enciclopedie e dizionari volumi di approfondimento quotidiani, settimanali e periodici pubblicazioni di fonte istituzionale working papers tesi di laurea e dottorato motore di ricerca nuove acquisizioni servizi covid- attività 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coordination motive. however, the predictive power of level-k models is significantly weakened when private information is introduced or the importance of the coordination motive is decreased. introduction the experimental literature on beauty contests and related guessing games has documented sub- stantial evidence that individuals tend to have a limited degree of strategic sophistication, especially in settings where the strategic reasoning is not straightforward. this is best illustrated by the “p- beauty contest” in which participants choose a number between and and whoever picks the number closest to a multiple p of the group average wins a prize. when p is less than one the game can be solved by iterative elimination of strictly dominated strategies, and the unique equilibrium is where every player chooses . in order to reach this equilibrium subjects need to go through a large number of rounds of elimination of dominated strategies. the experimental literature on beauty contests, however, shows that subjects usually perform one to three rounds of elimination and that their behavior is consistently different from the equilibrium prediction. the theory of level-k reasoning, first proposed by stahl and wilson ( ) and nagel ( ) with further extensions by ho, camerer, and weigelt ( ), costa-gomes, crawford and broseta ∗shapiro and zillante: belk college of business, university of north carolina, university city boulevard, charlotte nc - , usa; email address: dashapir@uncc.edu, azillant@uncc.edu. shi: department of eco- nomics, university of toronto, st. george street, toronto, ontario m s g , canada; email address: xian- wen.shi@utoronto.ca. we would like to thank stephen morris for many helpful comments and constant feedback. we are also grateful to vincent crawford, kirill evdokimov, and pei-yu lo for helpful comments and suggestions. this research was supported by funds provided by a childress klein research grant, the belk college of business, the connaught start-up fund at university of toronto and a sig award from sshrc of canada. ( ) and costa-gomes and crawford ( ), can be used to rationalize subject behavior in the p-beauty contest. the level-k model is based on the presumption that subjects’ behavior can be classified into different levels of reasoning. the zero level of reasoning, l , corresponds to non-strategic behavior when strategies are selected at random without forming any beliefs about opponents’ behavior. in the literature l is typically considered to be a person’s model of others rather than an actual person. level- players, l , believe that all their opponents are l and play a best response to this belief. level- players, l , play the best response to the belief that all their opponents are l and so on. for example, when p is equal to / in the beauty contest, level- players choose and level- players choose . as was shown in nagel ( ) and many other papers, there is indeed a salient pattern of levels of reasoning in the beauty contest setting. while level-k thinking is not particularly unique to the beauty contest (see e.g. costa-gomes and crawford, ), the structure of the game and its simplicity are very conducive to this type of behavior. success in the beauty contest largely depends on a person’s ability to correctly predict the average choice made by others. this explicitly forces individuals to think about decisions of other players. moreover, the symmetry of information makes this task relatively simple, which can further encourage participants to focus on the behavior of others. in many real applications, however, market participants often have access to both public and private information on the underlying fundamentals, and choose actions that are not only responsive to peer action choices but also appropriate to the fundamentals. a natural question then arises: how will level-k models perform beyond the classical beauty contest setting? to answer this question, we introduce a framework which generalizes the classical beauty contest setting along two dimensions. first, it allows players to have private information that is relevant for their action choice. second, it allows the importance of coordination to change so that the ability of correctly guessing other players’ actions may have a different impact on players’ payoffs. we then analyze how the predictive power of the level-k models varies along these two dimensions. the generalized framework that we use for our study is a modification of the morris and shin ( ) model (hereafter ms) on the social value of public information. in our setting, just as in morris and shin, the agents’ payoff is determined by two criteria: how well an agent’s action matches an unknown state of the world and how well his action matches the average actions of other agents. the relative importance of both factors can be varied within the model. in particular, as the latter becomes more important it makes the coordination motive of the game stronger. agents in our model receive two signals about the (unknown) underlying state. if both signals are public the information is symmetric. if one signal is public and the other is private (as in the original morris and shin setting) then the information is asymmetric and, in particular, different participants have different information. based on this framework we design several experimental treatments that differ from each other in the symmetry of information and in how important it is to predict the average action of other players. our main findings are as follows. first, in aggregate we find that subjects place less weight on the public signal than the ms model predicts. we show that this is consistent with the theoretical prediction of level-k models. an important implication is that, if agents have limited cognitive ability, the detrimental effect of increased public disclosure on social welfare may not be as strong as the ms model predicts. second, we compare individual subjects’ behavior with level-k predictions. we find that in treatments with public information and a strong coordination motive subjects’ behavior is consis- tent with level-k reasoning. in these treatments the percentage of individuals playing according to level-k models is as high as %, which is in sharp contrast with private information treatments or treatments with weak coordination motive where it never reaches %. another individual level finding is that the most commonly used level of reasoning in our data is l . this result holds robustly across most of the treatments. the most notable exception is the treatment with public signals and a strong coordination motive where the most common level was l . our last individual level result is that we do not find any evidence of level-k reasoning being more prevalent in the beginning of the treatment. thus our data do not support the common interpretation of level-k behavior as a model to describe subjects’ initial responses. finally, we perform maximum likelihood (ml) estimation of the level-k model and a closely related cognitive hierarchy model (ch) model introduced in camerer, ho, and chong ( ). we find that with few exceptions both models predict subjects behavior better than ne. the models are particularly successful in public information treatment with the strong coordination motive. in fact, regardless of the information structure when the coordination motive is stronger the estimated shares of strategic types (i.e. the types that are not level- ) are higher and are more likely to be significant. comparing the standard level-k model and ch we conclude that the ch performs better in matching the data. this is particularly surprising since the ch has fewer parameters (one for public information treatments and two for private information treatments) than the standard level-k model. overall, our analysis highlights the strengths and limitations of level-k models. the modified morris and shin framework used in our study is considerably more complicated than those typically used in the level-k literature. despite this complexity level-k models are very successful in predicting subjects’ behavior in settings that are close to the classical beauty contest, such as when the coordination motive is strong and information is symmetric. at the same time we find that the predictive power of level-k models diminishes as we move away from the classical setting and either weaken the coordination motive or introduce private information. our experimental findings also have important policy implications. the key insight in the analysis of morris and shin ( ) is that in equilibrium players often place too much weight on the public signal relative to the weight that would be used by the social planner. therefore, individual information aggregation is not socially efficient and enhanced public disclosure could hurt social welfare. however, our theoretical analysis of level-k reasoning shows that limited cognitive ability, either due to limited level of reasoning or incapability of bayesian updating, necessarily leads to subjects underweighting the public signal compared to the equilibrium prediction. we find in our experiment that subjects indeed put less weight on the public signal than the theory gneezy ( ) applies the framework of cognitive hierarchy to analyze first-price and second-price common value auctions with complete information, and finds evidence supporting the ch theory. predicts. this finding is also documented independently in a recent experimental study by cornand and heinemann ( ). this implies that limited cognitive ability can limit the detrimental effect of increased public disclosure. the rest of the paper is organized as follows. in section we discuss relevant literature on level- k thinking and the ms model. in section we provide a theoretical background for our study which is largely based on the ms model. we derive the prediction of level-k models in this setting and show that subjects with limited cognitive ability will put less weight on the public signal than the equilibrium predicts. section provides details of our experimental design and various treatments. our experimental results are reported in section . section then concludes and the experimental instructions are given in the appendix. literature review our experimental study contributes to the existing literature on the classical beauty contest begin- ning with nagel ( ), who first documents the clear pattern of level-k thinking in subject behavior. ho, camerer, and weigelt ( ); bosch-domenech, montalvo, nagel, and satorra ( ); costa- gomes and crawford ( ); and crawford and iriberri ( a,b), among others, have further developed and applied level-k models to beauty contests and related settings. however, most of the existing literature focuses on games with complete information. notable exceptions are crawford and iriberri ( a), who applied level-k reasoning to first- and second-price auctions, and a recent independent work by cornand and heinemann ( ), which is closely related to our paper. cornand and heinemann ( ) conduct experiments within the framework of the ms model and find that subjects put less weight on the public signal than the theory predicts. by assuming that all subjects use a common level of reasoning, they find that subject behavior is consistent with the second level of reasoning (l ). they further argue that, if all subjects behave according to l , the welfare result in morris and shin does not hold: increasing the precision of public information is always beneficial. their paper and ours share the same theoretical framework and both find that the increased disclosure of public information is less detrimental than the theory predicts. but there are important differences. they exclusively focus on the welfare implications of public disclosure, whereas our main focus is to test the performance of level-k models across settings with different information and payoff structures. moreover, we assume that the population consists of a mixture of different levels, whereas for the purposes of cornand and heinemann it was sufficient to assume a common level. the framework underlying our experimental study is first developed by morris and shin ( ) to evaluate the value of public information on social welfare in a coordination environment. sub- sequently, angeletos and pavan ( ) generalize their analysis of the social value of information by allowing both strategic complementarity and strategic substitutability among agents’ actions. the morris and shin framework has been applied to many different settings including asset pric- ing (allen, morris and shin, , bacchetta and wincoop, ), venture capital (angeletos, lorenzoni and pavan, ) and political science (dewan and myatt, , ). theoretical background this section provides a theoretical background for our study. the primary goal of our paper is to analyze performance of level-k reasoning in a setting which is similar to the classical beauty contest yet allows us to vary the importance of the coordination motive and information structure. for this purpose we use the morris and shin ( ) framework as a basis for our experimental analysis. however, since the original ms model cannot be directly implemented in the lab due to such assumptions as continuum of agents and improper uniform distribution we, first, need to modify it to adapt it to experimental environment. this is done in section . . in section . we use the modified ms framework to derive predictions of the level-k model. . modified morris-shin model there are n ex-ante identical agents, i = , ..., n. agent i chooses an action ai ∈ r. the payoff function for agent i is given by ui (ai, a−i,θ) = c − ( − r) (ai − θ) − r (ai − λa−i) , ( ) where c is a constant, θ represents the underlying state, r and λ are constants between and , and a−i is the average action of i’s opponents: a−i = n− ∑ j ̸=i aj. the payoff function has three terms. the first one is a constant c and is the highest payoff the individual can possibly receive. the second term reflects the loss from mismatching the underlying state θ and is simply the square of the distance between θ and ai. the third term is the “beauty contest” term. it measures the loss from mismatching the average action of opponents a−i which is scaled by λ. the parameter r measures the relative importance of coordinating with opponents’ actions versus matching the underlying state. when λ = and c = the game becomes the coordination game specified in ms. when r = and λ < the game becomes similar to the beauty contest in the sense that subjects only need to match λ times the average of other players’ actions. unlike the beauty contest, however, everyone, not just the player whose guess is the closest to the target, receives a non-negative payoff. our payoff function differs from the ms one in three ways. first, we consider a setting with a finite number of players while in ms there is a continuum of players. second, we introduce the term λ inside the payoff function to match the classical p-beauty contest. third, the payoff function in ms is always negative, which is difficult to implement in the laboratory. by adding a positive constant c to the original payoff function we allow participants’ payoffs to be positive without altering equilibrium predictions. as in ms, before taking actions, agent i will receive two signals about θ and we assume that both signals have the same precision α. the first signal y is always public and is given by y = θ + η, η ∼ n ( , /α) . ( ) as for the second signal, xi, it can be either public or private. if it is private, then xi = θ + εi, εi ∼ n ( , /α) , ( ) and η and εi are independent. if it is public, then it is the same across agents and is given by xi = θ + ε, ε ∼ n ( , /α) . again η and ε are independent. after receiving xi and y, agent i chooses action ai. morris and shin assume that θ is distributed with the improper uniform distribution over the real line in which case the expected value of θ given xi and y is ei(θ|xi, y) = y + xi . ( ) following the same procedure as in ms we can show that when xi is private the unique equi- librium is linear and is given by ai (y, xi) = − r − λr xi + − r ( − λr)( − λr) y. ( ) when signal xi is public, the unique nash equilibrium is ai (y, xi) = − r − λr xi + − r − λr y. ( ) notice, in particular, that when λ < and r = the ne is , as in the beauty contest. a major difficulty of implementing the ms setup in the lab is to generate θ according to the improper uniform distribution. to deal with this problem we adopted the following strategy. we generated θ using the uniform distribution on interval [a, b] and then given θ we generated the signals y and xi according to ( ) and ( ). after that we normalized state θ and signals (xi, y) by subtracting y from each of them, so that θn = θ − y, xi,n = xi − y and yn = . since the prior of θ has a bounded support, the formula ( ) to obtain e(θ|xi, y) may not be valid, and thus the ne would no longer be given by ( ) and ( ). however, normalized signals are immune to this problem. by the definition of y, we have θn = −η and xi,n = εi − η. since both −η and ε − η are normally distributed, by the standard formula for the conditional distribution of normally distributed random variables we have e(θn|xn,i) = e(−η|εi − η) = (εi − η) = xi,n . given that yn = this is the same as ( ). therefore, when agents observe normalized signals the ms logic and the equilibrium derivations remain valid. in the experimental design section we provide more details on how the normalization was implemented. . calculating levels of reasoning within the setting introduced in the previous section we derive actions that correspond to different levels of reasoning. from now on we assume that signals and the state are normalized and with slight abuse of notation we will use θ, xi and y(= ) to denote the normalized signals. it is convenient to introduce the variable µ = / so that player i’s updated estimate of the state can be written as ei[θ] = µxi. player i chooses ai to maximize ( ) and from the first-order condition the best response is a∗i = ( − r) ei [θ] + rλei [ā−i] . except for the non-strategic l type, agents with different levels of reasoning will form different beliefs about ei [ā−i] and will choose an action accordingly. the first step in calculating lk actions is to define the behavior of l . in the literature type l is usually viewed as the starting point of a player’s analysis of others’ actions, so it should be unsophisticated and non-strategic (see e.g. crawford and iriberri, ). in our paper we assume that l ’s actions are uniformly distributed between the two signals. under this assumption l ’s behavior is indeed unsophisticated and serves as a natural focal point for higher level players to start their reasoning (see discussion in crawford, ). furthermore, our specification is directly related to the l -specification in the standard beauty contest. in particular, when r = and signals are public, our game is reduced to a beauty contest game and the two l definitions coincide. given that l is non-strategic its behavior should not change as one signal becomes private or as we vary r. an alternative way to model l , which is related to truthful l in crawford and iriberri ( ), is to assume that the l type ignores all strategic aspects of the game (guessing other players’ actions) and focuses solely on the nonstrategic aspect of the game (guessing the state). in our setting these two approaches yield the same prediction for higher types’ behavior. according to the standard level-k model, an l agent expects that other players are l players. this means that an l player believes that the average action of other players will be equal to their own estimated state: ā−i = e−i [θ] = µx−i. in the setting when xi is private ei [x−i] = ei [θ] from which it follows that ei [ā−i] = ei [µx−i] = µ (µxi) = µ xi. therefore, an l player in the setting with private signals will play al = ( − r) µxi + rλµ xi. we use induction to derive the action choice of a level-n agent. let aln denote the action taken by an ln player with private signal xi. then it takes the following linear form aln = βnxi, where βn is a coefficient depending on r, λ and µ. in particular β = µ and β = ( − r) µ + rλµ . ( ) now consider an l (n + ) player with private signal xi. then she expects that other players are ln players and ei [ā−i] = ei [βnx−i] = βnµxi. therefore, aln+ = ( − r) ei [θ] + rλei [ā−i] = ( − r) µxi + rλµβnxi. when l ’s actions are uniformly distributed between the two signals the average l ’s action will be ei [θ] = xi, the exact same number that a (truthful) l type would choose. it follows that βn+ = ( − r) µ + rλµβn, which implies the following difference equation: (βn+ − βn) = rλµ (βn − βn− ) . using the initial condition ( ), we can solve βn = ( − r) µ − rλµ + ( − λµ) rµ (rλµ)n − rλµ . ( ) when signal xi is public, by following a similar procedure we can show that an ln agent with signal (xi, ) will choose action β̃nxi, where β̃n is given by β̃n = ( − r) µ − rλ + ( − λ) rµ (rλ) n − rλ . ( ) above we derived level-k predictions under the assumption that subjects are capable of correctly estimating signals received by others. for the setting with private signals we also consider an alter- native level-k model where players can not perform appropriate bayesian updating in estimating x−i. we call it a näıve level-k model and we assume that subjects are näıve in that they simply think that the other players’ private signal is exactly the same as their own. in the experimental part of the paper we will test whether subjects use näıve update or not and the frequency of actions consistent with näıve levels of reasoning. mathematically, näıve update is equivalent to the case when subjects receive two public signals. thus, the level-k prediction for näıve update is given by ( ). notice also that in this case if λ = then all level-k players will play action µxi regardless of k. it is clear from ( ) and ( ) that both βn and β̃n are decreasing in n and converges to our ne predictions given by ( ) and ( ) as n → ∞. therefore, we have proved the following result: proposition all level-k players choose higher actions than the ne prediction. when λ = the weights put on public and private signals sum up to . therefore, it follows from proposition that when λ = level-k agents will overweight the private signal and underweight the public signal as compared to the theoretical prediction. this has an important implication with regards to the ms model. one of the main results of morris and shin ( ) is that the coordination motive forces players to place too much weight on the public signal relative to the weight that would be used by the social planner. as a result, information is not aggregated efficiently and public disclosure of more information could be detrimental to the social welfare. however, proposition shows that the detrimental effect of public disclosure may be less than predicted by theory if agents are not fully rational. specifically, level-k players, whether näıve or not, put a higher weight on the private signal — and consequently a lower weight on the public signal — than ne predicts. experimental design the design of all treatments in our study is based on the modified ms framework as described above. in this section we explain our experimental implementation of the ms framework as well as similarities and differences across treatments. . payoff function and signals in all treatments the payoff function of subject i is given by ui(ai, a−i) = − ( − r)(ai − θ) − r(ai − λa−i) , ( ) where ai is the action of subject i, θ is the true state of the world, a−i is the average of all other subjects’ actions, λ ∈ [ , ] is the weight put on a−i, and r ∈ [ , ] is the relative importance of matching the weighted average of other investors’ actions. note that negative values of u(ai, a−i) are possible and so it was publicly announced to participants that negative payoffs would count as . otherwise, subjects may incur a large loss in a single period of the experiment that would be impossible to recover even if subjects receive the maximum of each period afterwards. to ensure participants’ understanding of the payoff structure we took advantage of the fact that each term had a very simple and intuitive interpretation. we started by verbally explaining that there are three factors that will determine the payoff: mismatching the underlying state, mismatching λa−i, and their relative importance r. after this was understood, we presented the actual mathematical form, explained the meaning of each term, and went through several numerical examples. finally, during the actual experiment at the end of each period the second and third terms in ( ) were calculated and displayed together with ai, θ, and λa−i. the information available to subject i was given by two signals: y and xi. the signals as well as state θ were generated prior to the experiment according to the following procedure. for each round t, state θ is generated randomly according to a uniform distribution on [ , ]. given θ, the signals are independently drawn from a normal distribution n (θ, ). signal y is public and is the same for all subjects. signal xi can be public or private. in treatments when it is private different subjects in a group observe different signals. when it is public all subjects observe the same signal. signals and the state were generated in such a way so that each period all groups of subjects received the same signals and the underlying state was the same. if, say, members of group received private signals , , and then in all other groups there would be a member who received signal , a (different) member with signal and so on. after the state and signals were generated, we normalized them by subtracting y from each of them so the triple (θ, xi, y) becomes (θ − y, xi − y, ) and the normalized signal y, therefore, is always . both normalized signals are then displayed on the computer screens and the payoffs are calculated using the normalized state value, θ − y. note that normalized x-signals and the this can potentially affect the equilibrium prediction since when the maximum of ( ) is negative the agent would be indifferent between all actions. however, one can show that this happens only when the two signals are very far apart. in our experiment this happened at approximately . % of all observations. normalized state could be negative. while the main reason for using the normalization is theoretical and was explained in section there are also additional benefits. first, it simplifies the environment as it is easier to make a decision with signals and than with signals and . second, this guarantees that subjects know that y was indeed a public signal. third, it makes our setting similar to the standard beauty contest setting. to keep matters simple subjects were not informed about the distributions used for state and signal generation. subjects were told, however, that the best guess for the state is the average of two signals (see instructions in the appendix for the exact wording). as one can see from section . , derivations of levels of reasoning and the equilibrium action do not require knowledge of the distribution as long as one knows how to estimate the state given the two signals. . treatment and session description there are four aspects in which the ms model differs from the classical beauty contest. first, in the ms model there is private information because agents receive private signals. second, the goal is divided between guessing λ-average and guessing fundamentals. third, the action domain is unrestricted. finally, in the standard ms model λ = and in the classical beauty contest λ < . the treatments designed for this paper will reflect these differences. it will be convenient to classify each treatment based on the information structure and value of λ. in total, there are three groups of treatments. in the first group signal xi is private and λ = . we label this group pr-a as the non-zero signal was private and the participants must match the average action of other investors. this environment is directly related to the ms model, especially when the domain is unrestricted. in the second group we set λ = / so that subjects need to match θ and one-half of the average action of their opponents. the latter consideration makes the game related to the p-beauty contest with p = / , however, the information is private and not public. we label the group pr-h where the h represents that individuals must now match one-half of the average action. our third group λ = / as in pr-h but both signals are public. as such only two signals are drawn every period, and it is common knowledge that both signals are public. we label this treatment pu-h as the non-zero signal is now a public signal and subjects need to match one-half of the average action. pu-h is directly related to the beauty contest especially when the domain is restricted. for a fixed information structure and value of λ we will vary values of r from . to . with higher r corresponding to a higher coordination motive. finally, for every information structure and (r, λ) pair there is a treatment where the strategy choice is bounded by the two signals, like in bc, and one where it is unrestricted, like in ms. given the goal of this paper it is instructive to be more precise regarding the relationship between pu-h and the beauty contest. first, similar to the beauty contest pu-h is the game with perfect information. second, when the choices are restricted to [ , xt] it makes pu-h dominance solvable. finally, as r gets closer to , the state, θ, becomes irrelevant with the only remaining to see this, recall that the best response is given by ai = ( − r) xi + rλa−i. without loss of generality we can assume xi > . because subjects are restricted to choose actions between [ , xi], we can first eliminate actions outside goal being to match a−i. one notable difference from the bc model is that here all subjects, not just the player who is closest to one-half of the average, are paid. however, the tournament aspect of the bc is still retained in that subjects with actions closer to λa−i in pu-h receive higher payoffs than those farther away. to sum up there is a group of treatments that is close to the ms model, pr-a; a group of treatments that is close to the beauty contest, pu-h; and a group of treatments that is in between the two, pr-h. table summarizes the information about the treatments, their mnemonic names, and the number of subjects in each treatment. y xi λ unrestricted domain restricted domain pr-a private pr-h private pu-h public table : description of experimental sessions and the number of subjects. sessions are based on one of the three designs described. within each session the information structure, value of λ and restrictions on the domain remained the same with the only variation being due to changes in r. each each consists of phases with rounds in each phase, for a total of rounds. within each phase the value of r is fixed but r is different across phases. we use six values of r: . , . , . , . , . and . . for each session we use the following order of r across phases: . , . , . , . , . , and finally . . thus, in the first phase (first rounds) subjects make decisions with r = . , while in the second phase (rounds - ) subjects make decisions with r = . and so on. note that we start with a low value of r, gradually increase r until phase four, decrease r between the fourth and fifth phases, and then increase it again. the choice of a non-monotone sequence of r’s can help us separate the effect of r from the effect of learning. for example, if subjects’ behavior is similar in phases with r = . (the first rounds) and r = . (the fifth ten rounds) then it suggests that this behavior is caused by low r and not by lack of subject’s experience with the environment. overall, our design enables us to vary the standard beauty contest setting in the following two directions. first, by changing r we vary the strength of the coordination motive. this is interesting because games in which the importance of coordination varies can capture a wide range of economic applications such as monetary policy (morris and shin, ), asset pricing (allen, morris and shin, , bacchetta and wincoop, ), venture capital (angeletos, lorenzoni and pavan, ) and political campaigns (dewan and myatt, , ). while levels of reasoning are well-defined for any value of r, one would expect that subjects will focus less on the actions of others as the coordination motive becomes weaker. if this is correct it would suggest that in games of the interval [( − r) xi/ , ( − r) xi/ + rλxi]. once we do that, we can further eliminate actions outside of the interval [ ( + rλ) ( − r) xi/ , ( + rλ) ( − r) xi/ + r λ xi ] and so on. by repeating this procedure we will get a sequence of intervals with length rkλkxi, and this sequence will shrink to a point, which is ne. due to time constraints the pr-h treatment with restricted domain had only five phases. the last phase (the one with r = . ) was not conducted. where coordination is less important or its effect is less obvious subjects will be less likely to follow level-k reasoning. second, we introduce private information into the game by making the second signal xi private. private information is prevalent in many economic applications and therefore it is important to understand how well level-k models can explain the data in settings with private information. indeed, level-k reasonings have been applied to classical settings with private information, such as the winner’s curse in common value auctions and overbidding in private value auctions (see crawford and iriberri, a). however, the comparison of level-k model performance between the complete and private information settings, both in absolute and relative terms, has not been studied yet. . procedures sessions were conducted at unc charlotte between and . subjects were typically undergraduate students, primarily recruited from the business school but not exclusively. subjects were seated at visually isolated carrels and were forbidden to communicate with other subjects throughout the duration of the experiment. instructions were read aloud to subjects, and a few minutes were spent discussing how different values of r could impact the subjects’ loss from mismatching the state θ (i.e. the term −( − r)(ai − θ) ) and the loss from mismatching the decisions of other investors (i.e. the term −r(ai − λa−i) ). to reinforce this distinction in the actual experiment after each round a payoff screen displayed the loss from mismatching each of these two terms as well as the total payoff. all subjects were divided into four-person groups which were re-assigned in the beginning of each period. in some sessions we had a number of subjects that was not divisible by . in those instances we used the following procedure. first, the computer would form as many groups as possible. the remaining subjects would form an incomplete group that was completed by the decisions of a subject(s) from fully completed groups. when relevant the subject(s) chosen from the fully formed group was the one who observed the private signal different from those observed by members of incomplete group. for instance, if the private signals in a fully completed pr-h were , , , and , and the private signals of an incomplete group were , , and , then a decision from a subject who saw a private signal of would be used to complete the incomplete group. even though the decision of this randomly chosen subject is used for two groups, that subject will only receive the payoff based on the outcome within her fully formed group. at the beginning of each round, subjects were shown signals and were asked to submit a decision for ai. depending on the treatment, subjects were informed that either both signals were public signals or one was a public signal and the other was a private signal only observable to that specific subject. when all decisions were submitted, a−i and profit were calculated for each agent. at the end of each round subjects were shown a screen containing their own action choice, ai, the true state, θ, the average opponent action, a−i and their payoff for the current round. subjects’ cash payment is determined as follows. at the end of the experiment one of the six phases is randomly chosen. a subject’s total payoff during the chosen phase is calculated and converted it into usd by multiplying it by . . thus, if a subject earned during the chosen phase it will become . $. this is in addition to the $ show-up fee that all subjects received. the average payment to subjects, including the show-up fee, was $ for a - minute session. results in this section we analyze subjects’ behavior and study how well it matches ne and level-k (lk) predictions. given that ne and lk actions are linear combinations of a random non-zero signal x and zero signal y, they will vary each period even when the treatment and the value of r, that is the session phase, are fixed. to make results comparable across periods and treatments we normalize the non-zero signal to be and adjust subjects’ actions as well as ne and lk predictions accordingly. for example, given action a and non-zero signal x, the normalized action is an = · a/x so that action a = x/ is normalized to and action a = x is normalized to . the interpretation of normalized values is that they represent the percentage weight a particular action or a prediction puts on a non-zero signal. as mentioned in section , two treatments for each set of parameter values and each information structure were conducted. in one the action domain is restricted to be between the two signals a subject receives and in the other the action domain is unrestricted. differences in behavior between those two treatments were minimal, and to keep the paper focused we present our findings using the pooled data from the restricted and unrestricted treatments. . comparing subjects’ behavior with ne and level-k reasoning first, we compare subjects’ behavior with ne predictions. for each treatment and each r we calculate the average normalized action an and plot it on figure together with the normalized ne prediction. as we see from figure , in all three treatments subjects’ actions are higher than ne predicts. in other words, subjects tend to overweight the non-zero signal which is private in pr-a and pr-h and public in pu-h. recall that, as we established earlier, overweighting the non- zero signal is consistent with level-k reasoning. using non-parametric signed rank test we have that most of the time the difference between observed behavior and ne is significant. more precisely, it is significant in all three cases for high values of r, that is when r = . and r = . . in pr-a the difference is significant for every r ̸= . , in pu-h for every r ̸= . . as for pr-h the difference is insignificant for r = . , r = . and r = . . figure shows the average of normalized actions for each treatment. in table we present the average absolute deviation of actions from ne (in normalized units). as we see deviations are quite substantial in all treatments and especially in treatments with private signals. notably, the observed behavior was closest to ne when r = . regardless of the value of λ and the information separate results for restricted and unrestricted treatments are available from the authors upon request. in a setting similar to our pr-a treatment cornand and heinemann ( ) also observed the overweighing of private signals by subjects. . . . . . . pr−a r w e ig h t o n n o n − z e ro s ig n a l . . . . . . pr−h r . . . . . . pu−h r ne a n figure : subjects’ behavior and ne in all treatments. on the y-axis is the average weight that subjects put on the non-zero signal which is public in pu − h and private otherwise. solid line is ne; and dash-dotted line, an, is the average over normalized actions. structure. the most likely reason is that r = . case was the last phase in each session and subjects’ learning could bring them closer to ne. level-k reasoning is usually thought of as the framework that describes people’s behavior in the beginning of experiments. therefore, a better performance of ne in the final stage of experimental sessions is not surprising. r . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . table : average absolute deviation of observed behavior from ne across different treatments and phases. the deviation is calculated based on normalized data with non-zero signal normalized to . higher r means stronger coordination motive. result : subjects tend to put a higher weight on the non-zero signal than ne predicts. this is consistent with level-k behavior. overall, ne performs the best in the last phase of the study with r = . . so far we established that aggregated subjects’ behavior is consistent with level-k predictions in that subjects overweight the non-zero signal. now we study whether this finding is the result of aggregation and whether it holds on the individual level as well. figure visualizes subjects’ behavior and the relationship between observed behavior and level- k predictions. from each of the three groups of treatments we picked three subjects and plotted their choices and levels of reasoning in the phase with r = . . the choices are denoted by crosses. the solid red line corresponds to l and dash-dotted magenta line corresponds to l . dashed black line in treatments with public signals correspond to l and dashed green line in treatments with private signals correspond to l naı̈ve. pr−a # pr−a # pr−a # pr−h # pr−h # pr−h # pu−h # pu−h # pu−h # figure : individual behavior of subjects in phase with r = . . crosses correspond to subjects’ actions; solid line is l and dash-dotted line is l . for treatments with public signals dotted line is l , for treatments with private signals dotted line is l naı̈ve . to increase the scale of images we use absolute values so that all levels and actions are positive. from figure we see that some subjects were following a particular level of reasoning in a fairly consistent fashion whereas some subjects were not. in particular, following level-k reasoning was considerably more common in treatments with public signals. subject , for example, was following l very consistently. subject was using l and subject seemed to converge to l by the second half of the phase. in treatments with private signals, on the other hand, such a pattern was less common. only subject in pr − h seemed to pick choices consistent with l naı̈ve; as for the remaining subjects, their behavior is harder to assign to a particular level of reasoning whether näıve or not. to quantitatively measure whether actions of a particular subject are consistent with level-k reasoning we use the following criterion. recall that each experimental session consisted of six -period phases with each phase corresponding to a particular value of r. we divided each phase into two halves: the first five periods and second five periods. within each group of five periods for each subject we calculated average absolute deviations of subjects’ normalized actions from normalized levels of reasoning (l , l , and l ). we say that a subject’s behavior closely followed one of the levels of reasoning during a given half of the phase if two conditions hold. first, the average deviation of subjects’ choices from this level was the smallest as compared to other levels. second, the average deviation from that particular level was less than normalized units. the reasons why we picked this criterion are as follows. level-k behavior is often considered as a way to describe subjects’ initial responses in which case it should be more pronounced in the beginning of the phase. furthermore, subjects’ behavior can change as the experiment proceeds; in particular, they can switch from one level to another, presumably a more sophisticated one. separately studying subjects’ behavior in the beginning and in the end of a given phase enables us to detect level-k behavior if it is used only in the beginning or if a subject switches levels within a phase. we allow for the error of up to normalized units in order to take into account that even if a particular subject uses level-k reasoning his choices are likely to be biased towards integers, particularly those ending with and . thus it is unlikely that subjects’ actions will precisely match a given level of reasoning. r . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . table : the frequency with which the first three levels of reasoning were closely followed. we say that a subject’s behavior closely followed one of the levels of reasoning during a given half of the phase if two conditions hold. first, the average deviation of subjects’ choices from this level was the smallest when compared to other levels. second, the average deviation was less than (in normalized units). table shows the frequency with which the first three levels of reasoning were closely followed in a given treatment. it is calculated as follows. we label decisions made by a particular subject during a particular half of a phase as whether following some lk or not. for private treatments we also include näıve levels of reasoning. then for given r and information structure we divide the number of half-phases where levels of reasoning were used over the total number of half-phases. several things can be noticed from table . first, in treatments with public signals the success rate of level-k models tends to be higher. second, the highest success rate occurs in treatments with two public signals and r = . where more than % of subjects followed some level of reasoning. this suggests that level-k models perform best when there is no private information and the coordination motive is the strongest. the third result, while in some sense being a corollary as a robustness check we also examined several alternative criteria. we performed the calculations using only the first five periods of each phase (as in crawford and iriberri, a) as well as pooling the data from all all ten periods of each phase. in addition to having the threshold of normalized units we considered thresholds of and normalized units. we also used actual values instead of normalized ones. in all these cases, the qualitative picture does not change. level-k models perform better in treatments with public signals and in phases with high r. quantitatively, numbers change as compared to table depending on whether the criterion is more or less favorable to level-k reasoning. if it is more favorable, say because of a higher threshold, then all frequencies are higher. if it is less favorable, say, because of a lower threshold or because we consider all periods of the phase instead of two five-period intervals, then all frequencies are lower. of the previous two, is worth mentioning separately. in treatments with private signals even when r = . the success rate of level-k models is relatively low and, in particular, is much lower than in treatments with public signals. result : in treatments with private signals and in phases with low r only a few subjects followed levels of reasoning. in treatments with public signals and high values of r level-k models did the best with the majority of subjects following some level of reasoning. the next question is how subjects’ behavior evolves over time. first, we study how the predictive power of the level-k model changes within the phase. given that level-k reasoning is usually viewed as the way to describe subjects’ initial responses we measure the performance of level-k models separately in the beginning and in the end of each phase. in table we calculate percentages of level-k subjects in the first five periods of each phase as well as percentages of level-k subjects in the last five periods of each phase. the criterion for attributing subjects’ behavior to a particular level is the same as before. that is the average absolute deviation from this level prediction should be the smallest compared to other levels and should not be more than normalized units. first rounds second rounds r . . . . . . . . . . . . pr-a . . . . . . . . . . . . pr-h . . . . . . . . . . . . pu-h . . . . . . . . . . . . table : percentage of subjects who followed closely one of the levels of reasoning in the beginning of the phase (the left table) and in the end of the phase (the right table). frequencies are computed similarly to table . comparing the left and right parts of table we find no evidence that level-k reasoning was more prevalent in the beginning of the phase. a simple comparison shows that in half-phases out of level-k behavior was more frequent in the beginning, in half-phases frequencies were equal, and in the remaining half-phases it was more frequent in the end. however, in the case of public signals and r ≥ . , which is when level-k reasoning was most common, we see it was used more frequently in the second half. furthermore, we do not see the evidence for level-k reasoning in the first phases of the experiments which were the phases with r = . and r = . . we conclude that our results are inconsistent with the conjecture that level-k reasoning is more likely to be observed in the beginning of the experiment. next, we turn our attention to the r = . and r = . phases of the treatments with public signals which is where level-k behavior was the most prominent. from table we see that in these phases level-k reasoning was more pronounced during the second half rather than during the initial five periods. looking at the evolution of subjects’ choices over time we have the following results. among those subjects who followed some level of reasoning in both halves of a phase there were cases (out of ) when subjects stayed with the same level in both halves, cases when subjects switched to a higher level, and case when a subject switched to lower level (subject , phase r = . , treatment pu-h). this is consistent with nagel ( ) who also found that subjects subject # r= . st half l l l l l l l nd half l l l ne l l l l l l l l ne l l r= . st half l l l l l l l l l l l l l l l l nd half ne l l l l l l l l ne l l l l l table : subjects’ behavior in pu-h treatment with unrestricted domain in phases with r = . and r = . . tend to adhere to the same level of reasoning throughout the entire study. for those subjects who followed some level in one half of a phase, only subjects did so in the first half while subjects did so in the second half. in other words, it was more likely for subjects to switch to level-k behavior than to abandon it. similarly, looking at subjects’ behavior between phases we see that those subjects who followed some level in the r = . phase would typically continue doing so, though perhaps using a different level, in the next (r = . ) phase. table summarizes the behavior of subjects in the pu-h treatment with unrestricted domain. for brevity we omit the similar table for subjects from the pu-h treatment with restricted domain. subject # r= . st half ln ln l nd half ne ne ln l ln r= . st half l l l ln ln ln nd half ln ln ln table : subjects’ behavior in treatment pr-a. only those subjects whose behavior could be attributed to any level are shown. subject’s ids below are for pr-a with unrestricted domain and those above for pr-a with restricted domain. in treatments with private signals, the picture is considerably less clear. table shows all participants in the pr-a treatments whose actions could be attributed to a particular level in at least one half-phase. the difference between tables and is immediate. out of subjects in pr-a treatments there were only who closely followed some level of reasoning during at least one half of at least one phase. that includes two instances when subjects followed ne. furthermore, nagel ( ) finds that subjects’ choices decreased over time which one may interpret as the evidence that subjects learn to play with higher levels of reasoning. nagel argues that this interpretation is false. the declining pattern of choices is not because subjects learned to play with higher levels of reasoning but because subjects adjusted downwards their beliefs about the average action given the outcome of the previous play. our experiment is different in that every period a new signal – or the support of the beauty contest game – is randomly drawn. therefore, subjects cannot directly use the information of the average action of the previous play to guess the average action of the current play. this makes learning much slower and more difficult in our setting. as a result we can observe many subjects staying with the same level of reasoning without adjusting subjects’ beliefs as in nagel ( ). levels of reasoning were not used in a particularly consistent manner. there are no subjects who would follow some level of reasoning throughout both phases, and only three subjects followed some level throughout the entire phase. result : we do not observe that subjects are more likely to follow level-k reasoning in the beginning of the phase as compared to the end, or vice versa. however, in phases where level-k behavior was most prominent, level-k reasoning was more common in the end. result : in treatments with public signals and high r subjects were more likely to switch to lk-behavior and within lk behavior they were more likely to switch to higher levels. in treatments with private signals such a consistent pattern is either not observed or is considerably weaker. the last question we want to address in this section is how frequently different levels of reasoning were followed by subjects. this information is given in table where we count how many times subjects followed a particular level of reasoning during a half of the corresponding phase. pr-a pr-h pu-h l l ln ne l (n) l (n) l n ne l l l ne . - ( ) - - - - . - - - - - - - . - ( ) - - . - ( ) - - . - ( ) ( ) - . - ( ) ( ) total: ( ) ( ) total %: . % . % . % . % . %( . %) . %( . %) . % . % . % . % . % . % table : each entry shows how many times subjects followed a given level within one half of a corresponding phase. in pr-h treatments columns l (n) and l (n) show both sophisticated and näıve levels. numbers for näıve levels are in parenthesis. numbers in the last row are calculated as a percentage of all phase-halves played by all subjects within a given treatment. several things can be noticed upon inspecting table . first, in treatments with private signals näıve levels were used more often than the “sophisticated” ones: versus in pr-a and versus in pr-h. second, in the treatments with public signals as well as in the pr-h treatment, l , regardless of näıvety, was followed most frequently. in pr-a we cannot separate l n from higher näıve levels but we still observe that l was followed more often than l . third, in the r = . and r = . phases of pu-h treatments higher levels of reasoning were used more often than in phases with lower r. in particular, in the r = . phase level l was followed more frequently than l . finally, we see the effect of learning. in the last phase of each treatment, the one with r = . , ne was followed most often. result : in all four treatments subjects were more likely to follow the first level of reasoning independent of näıvety. one notable exception is the r = . phase in treatments with public signals where l was most common. in treatments with private signals näıve levels of reasoning were considerably more common. given the popularity of näıve reasoning we conclude this section by studying whether such popularity is due to näıve updating or not. we added a belief-elicitation stage for treatments pr-a and pr-h with restricted domain. to minimize the interference between subjects’ responses to belief-elicitation and subjects’ action, the elicitation was conducted at the end of the round, i.e. after the decision was made, and only in the last three rounds of each phase. in other words among rounds for each given value of r, we added belief elicitation to the end of rounds , , . the belief elicitation consisted of a single question: “what was the average of private signals observed by other members of your group?”. while answering the question subjects could see their own private signal. to provide incentives subjects were paid for being close to the correct answer according to the formula max{ − (avgsignal−i − guessi) , }. denote subject i’s guess as gi and define αi so that gi = αi ·xi. if a subject with signals and xi can perform the update correctly then αi = / . for näıve updaters αi = . the average value of α for all subjects was . in pr-a and . in pr-h. a t-test could not reject the hypothesis of correct update with p-values equal to . for pr-a and . for pr-h. on the other hand the hypothesis of näıve update was rejected with p-values of . in both treatments. to investigate the issue further we assumed that subjects best responded to their beliefs regard- ing ā−i, which then could be calculated from the chosen actions. looking separately at subjects who followed a näıve level of reasoning (“näıve” subjects) and at those who did not, we observed the following. first, we did not find evidence of näıve update among “näıve ” subjects. typically “näıve ” subjects expected the average signal observed by opponents to be around xi/ . in fact, “näıve” subjects were more consistent in submitting xi/ than the others. second, for low values of r (up until . ) “näıve” subjects’ median expectation of λā−i/ was xi/ both in pr-a and pr-h. thus it seems that following a näıve level of reasoning was not due to näıve update regarding the signals observed by others. instead, näıve subjects were näıve regarding how the others would act on their information. for example, in pr-a they would anticipate that their opponents would take actions equal to their signal. they would correctly estimate the opponents’ signal to be centered around xi/ and would expect that average opponents’ action to be equal to xi/ as well. . maximum likelihood estimation of level-k and ch models our initial analysis of the data performed in the previous section indicated that the predictive power of level-k reasoning is weaker as we introduce asymmetric information or reduce the weight of the coordination component. in this section we turn to formal statistical analysis of the data to provide further evidence for this finding. we calculate the ml estimations of the following two models: the standard level-k model where lk type plays best response to the population that consists entirely of lk − type, and the cognitive hierarchy model (ch) where lk plays the best response to the population that consists of the mixture of lower types l , . . . , lk − . results of ml estimation of the standard level-k model are given in table . for the estimation we assume that l players choose their actions using the uniform distribution and lk players play the best response to the lk − strategy plus an error that is uniformly distributed around the best pr-a ( obs.) . . . . . . l . . . . . . l . . . . . . ln . . . . . . ne . . . . . . ll - . - . - . - . - . - . pr-h( obs.) l . . . . . . l . . . . . . l n . . . . . . l n . . . . . . ne . . . . . . ll - . - . - . - . - . - . pu-h ( obs.) l . . . . . . l . . . . . . ne . . . . . . ll - . - . - . - . - . - . table : maximum likelihood estimation of percentage of population that followed l , l and ne in different treatments. estimates are in bold when they are significantly different from at the % level. response. the estimation is performed using normalized values and the support of the error is set equal to normalized units, i. e. to % of the distance between two signals. in the literature the error is usually modeled as having a logistic distribution. we opted for the uniform distribution because subjects are often biased towards “nice” numbers such as integer numbers or those ending with and — something that we also observe in our data. the uniform distribution seems to be a more natural way to capture the error generated by such a bias. in all treatments we directly estimate the shares of l , l and ne types. in addition, in treatments with private signals we estimate shares of näıve types. the share of type l is then calculated as one minus the sum of the shares of other types. the results of ml estimation are consistent with our earlier findings. first, larger values of r generate larger and, most importantly, significantly positive estimates of shares of different types. furthermore, in treatments with public signals statistically significant level-k reasoning appear for lower values of r and the share of population using l and l are considerably higher than in treatments with private signals. looking at r = . and ignoring statistical significance and the ne-type, we see that in pr-a only . % used some level of reasoning; in pr-h it was only . %. for pu-h this number is . % which is more than times higher than pr-h and more than seven times higher than in pr-a. the most prevalent level of reasoning used by participants was level- , whether näıve or not. the most notable exception is the pu-h case with r = . where l ’s share was . % and l ’s share was . %. adding type l does not significantly change the results. it changes estimates slightly for the phase with r = . only. next, we estimate the cognitive hierarchy model (ch) that was introduced in camerer at al. ( ). the idea behind the ch model is that higher types believe that opponents’ population is a mixture of lower types. for example, type l believes that some opponents are l and others are l and best responds accordingly. camerer et al. assume that there is a correct distribution of different types given by the poisson distribution with parameter τ so that pr(lk) = f(k) = exp(−τ)τk/k!. each type does not realize that there are players of the same or higher types but it correctly estimates relative proportions of lower types. for example, type l will believe that the share of l is f( )/(f( ) + f( )) and the share of l is f( )/(f( ) + f( )). pr-a ( obs.) . . . . . . τ . . . . . . share of näıve . . . . . . ll - . - . - . - . - . - . pr-h ( obs.) τ . . . . . . share of näıve . . . . . . ll - . - . - . - . - . - . pu-h ( obs.) τ . . . . . . ll - . - . - . - . - . - . table : the ml estimation of the ch model. higher τ implies more evidence of level-k behavior. the estimation of treatments with public signals is straightforward. as before we assume that each type plays the best response plus the error that is uniformly distributed around the best response. the support of the error is normalized units. in estimation we assumed that the highest type in the population is l . for treatments with private signals, we adjust the ch estimation to account for näıve types. first, we assume that both näıve and sophisticated types are unaware of higher types. second, näıve types are unaware of the sophisticated types. for sophisticated types we considered two alternatives: one when sophisticated types are unaware of näıve types and another one when they are aware. we report only the former and the results for the latter were fairly similar. finally, we assume that the entire population is divided into two groups: näıve players and sophisticated players. the size of each group is an estimation parameter. within each group types are distributed according to poisson distribution with parameter τ. table shows the results of estimation. a higher τ implies that there are larger fractions of subjects who can do higher levels of reasoning. in pr-a the highest τ is actually at r = . after which it declines. this is consistent with what was seen in table where the treatment with r = . leads to the highest coefficients. in pr-h and pu-h the estimates of τ increase as r increases especially when r = . . except for the r = . case the τ values in pu-h are considerably higher than in treatments with private signals. one way to compare the performance of the two level-k models both across the treatments and with each other is to look at the estimated share of l . in our estimation procedure any action that was not consistent with a particular level of reasoning was assigned to level . thus higher share of l implies more observations that cannot be explained by a model. the results are presented in table . in addition to the already well-established fact that level-k models perform the best in public treatments with high r, we see that the performance of the ch model is considerably better. this is despite the fact that the ch model has fewer parameters than the standard level-k model. for example, in pu-h with r = . the ch model leaves unexplained only % versus % unexplained by the standard level-k model. level-k . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . ch . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . table : estimates of l by the standard level-k and the ch models. result : ml estimates confirm that level-k models perform the best when the coordination motive is the strongest and information is public. in the remaining cases level-k models perform poorly and put most of the weight on the non-strategic l type. result : in all treatments the ch model fits subjects’ behavior better than the standard level-k model, despite the fact that the ch model has fewer parameters than the standard level-k model. we conclude the section by comparing the effectiveness of estimated level-k models in predicting the aggregated subject behavior relative to the ne prediction. in table we calculate the absolute difference (in normalized units) between observed and predicted behavior by ne, level-k model and the ch model. we call these differences prediction errors. the comparison is done at the aggregated level; that is for each treatment we compare the average observed behavior with the average predicted behavior. differently from ne, both the standard level-k and the ch model assume heterogenous subjects’ behavior which is why we compare the three models only on the aggregated level. the panel with ne errors shows a picture which is very similar to figure . on the aggregated level ne performs quite well when r = . and when r = . and signals are private. in fact, r = . phase is the only phase where ne consistently outperforms the other two models. as we mentioned above the most likely reason is that r = . was the last phase and subjects’ behavior could converge to ne simply due to learning. for high values of r the ne error is around normalized units or more which corresponds to % of the distance between signals. both level-k models outperform ne for high r. this is despite the fact that on the individual level in treatments with private signals and high r we did not find strong evidence of level-k behavior. a particularly the ch model has one parameter in treatments with public signals and two in treatments with private signals. the standard level-k model has three parameters in pu-h, in pr-h and in pr-a. ne error . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . level-k error . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . ch error . . . . . . pr-a . . . . . . pr-h . . . . . . pu-h . . . . . . table : average deviation (in normalized units) of the observed behavior from the predicted behavior in ne and level-k models. striking result is that the error is as little as . in the r = . phase of pr-h; however, it appears to be a result of aggregation. finally, compared with level-k predictions the ne errors for r = . case are much higher in treatments with private signals. result : with the exception of r = . phase, both level-k models predict the aggregated behavior better than ne. their advantage is particularly pronounced in treatments with strong coordination motives. concluding remarks the goal of this paper is to determine the setting in which level-k thinking most appropriately describes subjects’ behavior. to do that we generalize the classical beauty contest setting by using a modified morris and shin ( ) framework that allows us to introduce private information and vary the strength of the coordination motive. having the experimental design based on the ms model generates an environment that is more complex than the one typically used in the level-k literature. despite this complexity we confirm the finding in the existing beauty contest literature that level-k models are indeed successful in predicting subject behavior when the game setting is close to the classical beauty contest, that is, when information is symmetric and the coordination motive is strong. moreover, most subjects choose their levels of reasoning consistently in the sense that they either adhere to one particular level or switch to higher levels. however, as we move away from the classical setting, subjects are less likely to follow level-k reasoning. in particular, only a handful of subjects play according to level-k reasoning and those who do tend to use it in a rather inconsistent manner. we conjecture that the reason for these results is as follows. when the coordination motive weakens, the behavior of other players becomes less important; as such, subjects are less likely to try to predict it. this is true regardless of whether information is symmetric or not. the introduction of private information into the model weakens level-k behavior even further since the task of predicting the beliefs and actions of opponents becomes considerably more complex. for example, in the p-beauty contest with p = / , l logic can be summarized in the following simple phrase: people will just pick actions randomly between and so the average action will be and so i should play . in contrast, in the setting with private information the same l logic becomes more complicated since subjects do not know the range from which others are choosing and have to estimate it. given the increased complexity of level-k reasoning, participants may rely on a different rule of thumb in settings with private information. for example, as our analysis shows subjects can take näıve approach regarding how other agents use their information. the identification of the exact rule of thumb subjects used in the experiment is an important research question, and we leave it for future research. appendix. instructions for treatment pr-h welcome to a decision-making study! introduction thank you for participating in today’s study in economic decision-making. these instructions describe the procedures of the study, so please read them carefully. if you have any questions while reading these instructions or at any time during the study, please raise your hand. at this time i ask that you refrain from talking to any of the other participants. general description this study consists of rounds, time permitting. in each round all participants (including you) have the role of investors. all participants are divided into groups with investors in each group. the division is random and will be re-done in the beginning of each round. you and the other investors in your group can invest some amount of experimental currency in a particular project. your task is to decide how much you would like to invest into this project. returns on your investment will be determined by the amount that you invest (ayou) and by the following two factors: • the project’s quality q; • one-half of the average investments made by others: · aaverage = · a + a + a ; example: assume that the other three investors in your group invested , and . the average amount invested by the others is aaverage = . one-half of the average then is · = . at the time when you make decisions you will not know either of these two factors. you will not know one half of the average amount invested by others, ·aaverage, because other participants are making their decisions at the same time as you. you will not know q because you must make your investment decision before q is revealed. therefore, you will need to decide how much to invest based on the information that will be made available to you. information. signals. in the beginning of each round you and all other investors in your group will receive two signals that will provide you with information about the project’s quality. both signals are randomly drawn given the project’s quality q. because signals are randomly drawn it is impossible to precisely predict q given the signals. however, they will give you an idea of a range where q might be. the table below shows to you how signals should be interpreted. first, to make calculations easier for you one signal is always set equal to . second, given the two signals that you will see the best guess of q will be simply the average of the two signals. because of the randomness it is unlikely that q will ever be precisely equal to the average of the two signals. the last two columns in the table give you an idea of how precise your guess is. you see that in two cases out of three, i.e. with probability / , the quality, q, will be at most away from the average and with probability % the quality will be at most away from the average. signal signal the best with prob. / with prob. % guess of q q will be in q will be in s ( +s)/ ( +s)/ ± ( + s)/ ± example : assume that you received two signals and . then the best guess of the project quality would be ( + )/ = . with probability of / you can conclude that the project quality will be between (= − ) and (= + ) and with probability % the project quality will be between - and . in the remaining % of the cases the quality will be outside of the [− , ] interval. guessing one-half of the average in the previous section we explained how to guess q given the information that you will receive (the two signals). however, your profit will also depend on how well you can guess one-half of the average amount invested by other investors in your group. the decisions of other investors are decisions made by humans and therefore there is no precise theory that will tell you where one-half of the average will be. therefore, your best option would be to try to predict how much the other investors are going to invest given their information. here is what you know and what you don’t know about the information available to other investors in your group: • they receive two signals, just like you do; • you know the first signal that everyone receives. it is . all investors in your group will have as the first signal. • you do not the second signal that they receive. the second signal is a private signal. it means that you cannot see private signals received by other investors. it also means that they cannot see the private signal that you receive. • you do know that private signals of other investors are generated in the same way as your private signal. most importantly that they are also centered around the project’s quality q. use your knowledge about the information that other investors have to predict how much they will invest. based on that you can form your guess of one-half of the average investment. your profit and cash payments your profit will be calculated as follows. in the beginning of each round you will be given experimental points. from this amount we will deduct points when your action does not match the project’s quality. we will also deduct points when your action does not match one-half of the average investments made by others. your final profit will be calculated by the following formula: payoff = − ( − r)(ayou − q) − r ( ayou − aaverage ) . the first term says that your investment will bring you at most . the second term determines your loss from mismatching the project’s quality q. the third term determines your loss from mismatching one-half of the average investments made by others. it is possible that the project quality and one-half of the average investment will be two different numbers. in this case parameter r measures the relative importance of matching the investments of others versus matching the quality. a lower r means matching the quality is more important. relative importance will be changed every rounds. the following two examples are used to illustrate how r impacts your payoff. while you will submit decisions for these two examples they are for illustrative purposes and will not impact your payment. example: let r = . so that is it is more important to match the quality. let quality, q, be , and aaverage be . at your computer terminal, please submit an action of now. if your action, ayou, is then your loss from mismatching the quality is ( − . )·( − ) = . your loss from mismatching one-half of the average investments is . · ( − ) = . you see that your mismatch of the average investment is larger than the mismatch of quality, but your losses from mismatching the quality are higher. your total profit is − − = . example: now assume that r = . so that is it is more important to match the investments of others. as before assume that q = and aaverage = . thus everything is the same as in the example above except for r. again, please submit an action of now. your loss from mismatching the quality is ( − . ) · ( − ) = and your loss from mismatching the average investment is much higher and is equal to . · ( − ) = . your total profit is − − = . the profit that you made in each round will be converted into cash by the following procedure. the study lasts for rounds. in the end of the study we will openly and randomly choose a sequence of rounds: either from round to round , or from round to round and so on. your cash earnings will be equal to the total profit that you earned during these rounds times . . this is in addition to the $ that you receive as a show-up fee. for example, if round to is chosen and you earned during these rounds your cash payoff will be: · . + = $ . if in a particular round you make a negative profit it will count as . summary the study consists of rounds, time permitting. in the beginning of each round, the computer will generate the project quality q and randomly determine other investors who will be in your group. computer will also generate two signals for each participant. the first signal — zero — will be the same among all participants. the second signal will be private. it means that you cannot see the signals received by other investors, and they cannot see the second signal received by you. your task is to submit an amount that you would like to invest. after you and all other members of your group enter their decisions, the computer will calculate and display your profit in that particular round. your profit will be determined based on how well you guessed the project’s quality and how well you guessed one-half of the average investment made by others. in the end of the study we will take the profit you made in a randomly chosen sequence of rounds and will convert it into cash payment. references [ ] allen, franklin, stephen morris and hyun song shin ( ). “beauty contests and iterated expectations”, review of financial studies, , - . 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[ ] stahl, dale and paul wilson ( ). “experimental evidence on players’ models of other players.” journal of economic behavior and organization, , – . wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ editorial dr. andreas sputtek institut für transfusionsmedizin universitätsklinikum hamburg-eppendorf martinistraße , hamburg, germany tel. + - , fax - , e-mail sputtek@uke.uni-hamburg.de website www.sputtek.de © s. karger gmbh, freiburg accessible online at: www.karger.com/tmh fax + e-mail information@karger.de www.karger.com published online: july , in the days of beginning global warming: cool is beautiful andreas sputteka allison hubelb a institut für transfusionsmedizin, universitätsklinikum hamburg-eppendorf, hamburg, germany b department of mechanical engineering, university of minnesota, minneapolis, mn, usa when blood is withdrawn from a human being, this is the be- ginning of hypothermia – provided this is not done at ambient temperatures at or above °c (i.e. . °f, k). the same holds for any tissue or organ removed at room temperature. this removal is already the start of a sometimes not very well controlled cooling process; it is the first step towards hy- pothermia, which is characterized by a lowering of biochemi- cal and biophysical reaction rates. for biochemical reactions, this relationship is well described by the arrhenius law, which can be written in various forms, one of which is k = a e –e/rt ( ), where t is the absolute temperature, a is a constant, e is the activation energy of the reaction and r is the gas constant. thus, an arrhenius plot of ln k as a function of /t yields a straight line with slope –e/r. however, in a sequence of reac- tions each step may have a different activation energy which makes the overall effect of a change in temperature quite un- predictable. keeping this in mind, what happens to a mammalian organism when controlled cooling down to °c in parallel to exsan- guination is performed, followed by an asanguineous perfu- sion by special blood substitution fluids for several hours, and controlled rewarming? this is described in the article by tay- lor [ ] in this issue. the good news for people in the field of transfusion medicine is that blood was needed again after the rewarming and that the dogs were not able to play chess after- wards (nor had they been before). however, in times of an ex- isting shortage of red cells for transfusion, the demonstrated efficacy of these synthetic, acellular solutions justifies their consideration for multiple organ harvesting from cadaveric brain-dead heart-beating donors. from a protein’s point of view the removal from a ‘warm’ or- ganism is the beginning of dampening of the molecular mo- tions and the elimination of conformational transitions – in other words, denaturation. the structure of a protein is deter- mined by intermolecular and intramolecular interactions, such as van der waals interactions as well as polar, hydrogen and ionic bonds. when we cool, e.g. fresh frozen plasma, we re- duce the activity of the surrounding water, and we expose the proteins to solutes that may alter their chemical activities and affect their secondary and tertiary structure. fortunately most of the proteins intended for a later use in patients (e.g. to stop bleeding) seem to tolerate this well, provided we freeze the plasma rapidly, store it at sufficiently low temperatures and rewarm it quickly. the article by ragoonanan and aksan [ ] in this issue reviews the methods we have at present for pro- tein stabilization and proposes a new stabilization method termed ‘nanoencapsulation’. on a cellular level, the removal of a cell, tissue, or an organ from a living organism is the start of hypoxemia as well, and in combination with hypothermia both effects may lead to cell, tissue, and organ damage. so why not simply keep the temper- ature at the level it is inside the organism? the answer is that slowing down biophysical and biochemical reactions may be what we want to achieve when hypoxemia takes place. as a rule of thumb, oxygen consumption is halved for each °c drop in temperature. another answer is that we want to make life less comfortable for contaminating microbiological ‘guests’ once the biological material is not ‘safe-guarded’ by a fully functional immunological system. both answers apply to the storage of red cells for transfusion at °c: they are not expected to perform a lot of anaerobic glycolysis. generally this requires a temperature (mostly found empirically by trial and error) which is not too low for the target cell, tissue or organ but low enough for the undesired microbes. however, it is known that the activity of the na-k pump in human ery- throcytes at °c is only . % of that at °c [ ]. the rate of ion pumping at such low temperatures is unable to match the passive ion fluxes and there is a net gain of na+ and cl– (asso- transfus med hemother ; : – doi: . / dr. andreas sputtek institut für transfusionsmedizin universitätsklinikum hamburg-eppendorf martinistraße , hamburg, germany tel. + - , fax - , e-mail sputtek@uke.uni-hamburg.de website www.sputtek.de http://dx.doi.org/ . % f transfus med hemother ; : – sputtek/hubel ciated with a k+ loss) which osmotically draws in water and leads to cell swelling. as a consequence the hematocrit in stored red cell units increases towards the end of the storage period. on the other hand, platelets for transfusion are stored at room temperature in gas-permeable bags under agitation because platelets need oxygen for their aerobic glycolysis. they also need to get rid of the carbon dioxide produced as a result thereof: otherwise the resulting drop in ph leads to their inactivation. the work by josefsson et al. [ ] in this issue is an example of how complex the phenomena are when chill- ing platelet concentrates to different temperatures and for dif- ferent periods of time. they propose a mechanism which ex- plains the fact why chilled platelets are rapidly removed from circulation despite high functionality and also propose meth- ods for intended ex vivo preservation. there is no doubt that there is a growing interest in how to harness the natural ability of living cells to survive another un- friendly treatment: freezing. cryopreservation of somatic and reproductive cells and tissues has a wide range of applications in biotechnology, biomedicine, agriculture, forestry, aqua- culture, biodiversity conservation and – transfusion medicine. the cryopreservation of blood cells can be regarded as a clas- sical field of development and application of low temperature biology. the review by sputtek et al. [ ] summarizes from where we have progressed to where we are now. new con- cepts are being derived from the growing appreciation of the use of polymeric extracellular cryoprotectants. cellular thera- pies based on the use of hematopoietic stem cells either from bone marrow or peripheral blood have become a standard therapy for a variety of diseases, and some transfusion medi- cine-based institutions were fortunate and clever enough not to miss this train. the article by fleming and hubel [ ] sum- marizes the emerging science, technology and issues in this field regarding aspects of cryopreservation. in their paper, woods et al. [ ] summarize what is known about procedures for cord blood stem cell cryopreservation. while umbilical cord blood has been known to be a rich source of hematopoi- etic stem cells capable of providing hematopoietic reconstitu- tion, more recently it has also been investigated as a potential source of mesenchymal stem/progenitor cells. under correct cytokine stimulation, these cells exhibit the mesenchymal lin- eage capacity to form bone, fat and cartilage. they are usually prepared and cryopreserved using methods prescribed for hematopoietic progenitor preservation; optimized methods specific to this cell type have yet to be fully investigated. from an ‘evolutionary’ perspective, blood banking can be re- garded as a first step to tissue and organ banking. patients will increasingly benefit from donated bone, cartilage, corneas, skin grafts and heart valves. people running a blood bank are experts in organizational requirements (e.g. record keeping and working in accordance with standard operating proce- dures), acquisition (e.g. ethical and legal rules, anonymity, donor screening and selection), processing (e.g. identification, inspection, storage, expiration, irradiation, sterilization, freeze-drying, quality management), labeling, distribution, and transportation. the above-mentioned prerequisites are al- ready implemented in a modern blood bank, so why not take the chance as described in the contribution by rebulla et al. [ ] in this issue to diversify into a ‘biobank’? today, ‘life and death at low temperatures’ (with a bow to basil luyet and his famous book) [ ] would not be com- plete without an article about the banking of human embryon- ic stem cells. pluripotent human embryonic stem cells tend to differentiate into cells from all germ layers when being kept in culture. therefore, an essential prerequisite for the devel- opment of treatments with these cells is setting up banks of well-characterized and safety-tested cells for research – and even more important for therapeutic applications. currently conventional freezing (rather low concentrations of cryopro- tectants and slow cooling) or vitrification (high concentrations of cryoprotective cocktails and extremely rapid cooling) have been applied with varying degrees of success. the article by hunt [ ] reviews the debate and describes the current prac- tice at the uk stem cell bank. finally: we want to emphasize that our underlying scientific discipline, termed ‘cryobiology’, does not subscribe to, and in fact views with skepticism, the practice of ‘cryonics’. the prac- titioners of cryonics freeze entire bodies or detached heads of deceased persons in anticipation of their reanimation to a nor- mal living individual, a practice which has no scientific basis. to paraphrase arthur w. rowe, co-author of [ ] (personal communication): ‘believing that cryonics could result in rean- imation of a human being after having been frozen is like be- lieving you could turn hamburger back into a cow’. references taylor mj: hypothermic blood substitution: special considerations for protection of cells during ex vivo and in vivo preservation. transfus med hemother ; ( ): – . ragoonanan v, aksan a: protein stabilization. transfus med hemother ; ( ): – . willis js, ellory jc, wolowyk mw: temperature sensitivity of the sodium pump in red cells from various hibernator and non-hibernator species. j comp physiol ; : – . josefsson ec, hartwig jh, hoffmeister km: platelet storage temperature – how low can we go? transfus med hemother ; ( ): – . sputtek s, kühnl p, rowe aw: cryopreservation of erythrocytes, thrombocytes and lymphocytes. transfus med hemother ; ( ): – . fleming kk, hubel a: cryopreservation of hematopoietic stem cells: emerging science, tech- nology and issues. transfus med hemother ; ( ): – . woods ej, pollok ke, byers ma, perry bc, heim- feld s, gao d: cord blood stem cell cryopreserva- tion. transfus med hemother ; ( ): – . rebulla p, lecchi l, giovanelli s, butti b, salvater- ra e: biobanking in the year . transfus med hemother ; ( ): – . luyet bj, gehenio pm: life and death at low temperatures. normandy, biodynamica, . hunt jh: the banking and cryopreservation of human embryonic stem cells. transfus med hemo- ther ; ( ): – . op-bjps .. everettian confirmation and sleeping beauty: reply to wilson darren bradley abstract in bradley ([ b]), i offered an analysis of sleeping beauty and the everettian interpretation of quantum mechanics (eqm). i argued that one can avoid a kind of easy confirmation of eqm by paying attention to observation selection effects, that halfers are right about sleeping beauty, and that thirders cannot avoid easy confirmation for the truth of eqm. wilson ([forthcoming]) agrees with my analysis of observation selection effects in eqm, but goes on to, first, defend elga’s ([ ]) thirder argument on sleeping beauty and, second, argue that the analogy i draw between sleeping beauty and eqm fails. i will argue that neither point succeeds. introduction background wilson’s argument for i in sleeping beauty reply: explaining away the crazy wilson’s argument for the breakdown of the analogy reply: the irrelevance of chance conclusion introduction in my ([ b]), i offered an analysis of sleeping beauty and the everettian interpretation of quantum mechanics (eqm). i argued that one can avoid a kind of easy confirmation of eqm by paying attention to observation selec- tion effects, that halfers are right about sleeping beauty, and that thirders cannot avoid easy confirmation for the truth of eqm. wilson ([forthcoming]) agrees with my analysis of observation selection effects in eqm, but goes on to, first, defend elga’s ([ ]) thirder argument on sleeping beauty and, second, argue that the analogy i draw between sleeping beauty and eqm fails. i will argue that neither point succeeds. brit. j. phil. sci. ( ), – � the author . published by oxford university press on behalf of british society for the philosophy of science. all rights reserved. for permissions, please email: journals.permissions@oup.comdoi: . /bjps/axt the british journal for the philosophy of science advance access published april , by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ after setting up the background in section , i discuss the first point in sections and , and the second point in sections and . i conclude in section . background consider the following two cases: quantum wombat: wombat is about to perform a spin measurement with possible outcomes up and down. quantum mechanics says that up and down each has a chance of fifty percent. according to eqm, the universe will divide, so wombat will have two future successors, one of whom will observe up, and one down. according to stochastic theory (st), there will be only one future successor, who will observe either up or down, each with fifty percent probability. wombat is unsure whether eqm or st is correct, and assigns each a credence of fifty percent. after branching and observing either up or down, what should wombat’s credence in st be? some say it should stay at ½; call this ‘no-easy-confirm- ation’. others say it falls to i; call this ‘easy-confirmation’. technicolour sleeping beauty : beauty will be put to sleep on sunday night and woken on monday. a fair coin is tossed on monday night. if the coin comes up heads, beauty will not be woken on tuesday. if the coin comes up tails, beauty will be woken on tuesday. beauty’s memory of her monday experience will be erased on monday night; so each waking is initially subjectively indistinguishable from every other. however, shortly after each waking beauty will be shown either a red or a blue piece of paper. if tails comes up, she will be shown red on one day and blue on the other, with a further fair coin determining on which day she’ll be shown which colour ; if heads comes up, she will be shown either red or blue on monday, depending on the toss of a further fair coin. beauty knows all this. on waking and seeing a red piece of paper, what should beauty’s credence in heads be? ½ (so say halfers) or i (so say thirders)? in both cases, there are two possible worlds: a world with one successor (heads/st) and a world with two successors (tails/eqm). and in both wilson and i agree that modifying the original sleeping beauty problem by changing the coin toss to monday doesn’t change anything, so i’ll discuss this variant. other details we agree on will also be suppressed. there is a slip in wilson’s description of the case. he says, ‘if tails comes up, she will be shown red on monday and blue on tuesday’. he confirms (personal correspondence) this is not what he meant. darren bradley by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ cases, the three possible observers have the same subjective experiences. the parallel can best be seen in figure . i’ll now briefly recap my ([ b]) arguments, and highlight the points where wilson disagrees. in my ([ b]), i made three claims that are relevant here. first, i gave an analysis of quantum wombat, which supports no-easy-confirmation. one aim of my argument was to deny the claim, which i attributed to papineau and durà-vilà ([ a], [ b]), that the total evidence quantum wombat has on waking and observing up is, ‘there is a branch in which up occurs’. such evidence would indeed confirm eqm. instead, i argued that the total evidence is something like, ‘i learn that up occurs in this branch by a random procedure’ (where a random procedure would select each waking day with equal chance). such evidence does not favour eqm over st, so there is no easy confirmation. i’m gratified that wilson agrees with this analysis. second, i gave an analogous analysis of sleeping beauty that supports halfers. one aim of my argument was to deny the claim, which i attributed to titelbaum ([ ]), that the total evidence sleeping beauty has on waking and seeing a red piece of paper is, ‘there is a wakening on which the red paper is observed’. such evidence would indeed confirm tails. instead, i argued that super- position up or down sunday monday monday tuesday sunday heads tails st up down super- position eqm figure . the analogy between sleeping beauty and eqm. though not using that name, which is wilson’s. though he does poke at a squishy bit in the argument regarding the principle of indifference and suggests a way to firm it up. i suggest a different way in my ([ ], p. ). everettian confirmation and sleeping beauty by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ the total evidence is something like, ‘i learn that today is a red paper day by a random procedure’. such evidence does not favour tails over heads, so there is no support for thirders. wilson agrees with this analysis too. however, he thinks there is a different route to the thirder position, that of elga ([ ]), which is based on the principal principle (to be explained shortly). i will argue in section that this route doesn’t succeed either. so i will defend: (a) elga’s ([ ]) argument for the thirder position, based on the prin- cipal principle, fails. third, i suggested in my ([ b]) that due to the parallels between quantum wombat and sleeping beauty, the following conditional holds: (b) if you are a thirder in sleeping beauty, you are committed to easy confirmation of eqm. wilson denies (b). i’ll explain wilson’s denial of (a) in section and criticize it in section . i’ll explain wilson’s denial of (b) in section and criticize it in section . wilson’s argument for i in sleeping beauty wilson agrees with me that the evidence beauty has on seeing a coloured piece of paper doesn’t confirm tails as some thirders claim. instead, wilson offers a different route to the thirder conclusion, via elga’s ([ ]) argument. to understand elga’s argument, we need the principal principle and the concept of inadmissible evidence. the principal principle connects chance with rational belief. we can use wilson’s locution (based on lewis [ ]): principal principle (pp): where an agent knows the chances and has no inadmissible evidence, the agent’s credences should match the chances. and we can understand inadmissible evidence as: inadmissible evidence: evidence that justifies an agent in having a cre- dence that deviates from the known chances. wilson says his argument uses the following assumption: the [. . .] assumption is that chance is the norm of credence: that in a situation where an agent knows the chances and has no inadmissible information, the agent’s credences should match the chances [pp]. where a fair coin toss is in the future, an agent cannot have inadmissible information about it without the help of precognition or some other form of backwards causation. (wilson [forthcoming]) in fact, there are two assumptions here. i agree with the first sentence— pp—and disagree with the second, which is a claim about what information darren bradley by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ is inadmissible. wilson’s argument ([forthcoming]) needs both assumptions; it runs as follows: let cr be sleeping beauty’s credence function after waking but before being told what day it is: (i) cr(headsj today is monday)¼½, by the pp, (ii) cr(headsj today is tuesday)¼ , (iii) cr(today is tuesday) > , therefore, cr(heads) < ½. reply: explaining away the crazy i deny (i). wilson doesn’t just apply pp; he assumes that ‘today is monday’ is admissible evidence. it would be admissible evidence if ‘precognition of some other form of backwards causation’ were required for inadmissibility, as wilson suggests ([forthcoming]). i claim that beauty has inadmissible evidence without backwards causation. though this doesn’t come up in my ([ b]), i gave a detailed argument in my ([ a]), which is based on (lewis [ ]) and which wilson doesn’t discuss. but he does say that the position defended there is ‘crazy’ and ‘implausible’. so i will try to make the position more plausible. i hold that beauty should have credence a that a future coin toss will land heads: (i*) cr(headsj today is monday) ¼ a, by the pp, correctly understood. i agree that this is odd. but oddity is no objection by itself—sleeping beauty is in an odd position. what i hope to show is that the oddity i endorse is independently motivated. what follows in this section is a sketch of the argu- ment of my ([ a]), with an emphasis on making the position intuitively acceptable. consider the following case: imperfect crystal ball: suppose you have an imperfect crystal ball. you can ask it about the result of any particular coin toss. whenever the coin will land heads, it shows you a picture of the coin showing heads. but whenever the coin will land tails, it shows you nothing. suppose you ask the crystal ball about some particular toss, look into the crystal ball and it shows you nothing. titelbaum ([ ]) shows that even the double-halfer position (where beauty’s credence on waking and then learning that it’s monday should stay at one half)) cannot avoid embarrassment. everettian confirmation and sleeping beauty by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ does this confirm tails? yes. one way to put this is to say that you have discovered an absence of evidence for heads, and this confirms tails. another way to put this is to say that the evidence space was {image of heads, image of nothing}, and when one piece of evidence confirms a hypothesis (image of heads), the negation of that evidence (image of nothing) disconfirms the hypothesis. now imagine someone who looks at the image-free crystal ball and says: ‘the crystal isn’t working. so you have no inadmissible evidence and should follow the pp and believe heads with fifty percent certainty’. they would be wrong. if they had correctly taken into account not just the absence of the image in the crystal ball but the whole evidence space, they would see that you have evidence for tails. i claim the same thing happens to sleeping beauty. imagine her, after waking, about to be told what day it is. the evidence space is {today is monday, today is tuesday}. if she learns that today is tuesday, this is conclusive evidence that the coin landed tails. so if she fails to learn that today is tuesday—if she learns that it is monday instead—this is evidence that the coin lands heads. so learning that it’s monday is relevant to the future coin toss. it is tempting to say, as the thirder does, ‘you have no inadmissible evidence and should follow the pp and believe heads with fifty percent certainty’—that is, (i). but, i claim, that would be a mistake. if we take into account the whole evidence space, we can see that beauty has evidence for heads—that is, (i*). therefore, we can conclude that (a): elga’s ([ ]) argument for the thirder position fails. wilson’s argument for the breakdown of the analogy let’s put that aside and grant that wilson’s argument for the thirder position in sleeping beauty succeeds. i suggested in ([ b]) that: (b) if you are a thirder in sleeping beauty, you are committed to easy confirmation of eqm. the argument for (b), in as much as i gave one, was simply that it seemed to follow from the parallels described at the beginning of this article. as i put it: thirders think that beauty gains on waking some reason to believe that the possible world in which there are more observations (tails) is more probable than the world with fewer (heads). the analogous position i assume here that on learning what day it is, beauty should update by conditionalization. there is no memory loss during this period so no reason to deny conditionalization. either way, wilson gives no indication that he does. darren bradley by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ regarding eqm is that we gain some reason after branching to believe that the possible world in which there are more observations (eqm) is more probable than the one with fewer (st). as branching is happening all the time, it would follow that we have overwhelming evidence in favour of eqm! [. . .] if thirders are to reject this easy evidence for [eqm], they owe us an explanation of where the disanalogy lies between sleeping beauty and eqm. ([ b], p. ; notation altered) wilson attempts to give an explanation of where the disanalogy lies. he argues that confirmation in eqm does not depend on a chance process, whereas confirmation in sleeping beauty does. as we saw above, wilsons’s thirder argument relies on pp, which relies on a chance process generating heads or tails. as there is no chance process determining st or eqm, the pp is inapplicable, so the thirder argument in sleeping beauty does not transfer to easy confirmation for eqm. here’s how wilson puts it: the disanalogy between sleeping beauty (sb) and quantum wombat (qw) is, on reflection, a straightforward one. whether eqm or st is true does not depend on any chance process, and wombat knows that. in contrast, whether the coin lands heads or tails does depend on a chance process, and beauty knows that. (wilson [forthcoming]) reply: the irrelevance of chance the first thing to say is that coin flipping is really a non-chancy process—how a coin lands is determined by how exactly it was flipped and caught. however, let’s grant wilson that the coin flip in sleeping beauty is chancy. my main response is that it’s implausible that the presence or absence of chance could make the difference wilson needs it to. let’s distinguish the question of beauty’s reason for her prior probability from the question of whether she gains evidence that shifts the credence from the prior probability. that is, we should distinguish what generated pr(h) from whether pr(hje) > p(h). in sleeping beauty, the pp just fixes the prior probability of h (the former question). however, the issue between halfers and thirders is whether beauty receives new evidence on waking that shifts her credence (the latter question). halfers say no; thirders say yes. this issue, i claim, isn’t affected by what the prior is based on. i’m grateful to a referee for stressing this point. the fact that we can grant this so easily indicates that chanciness doesn’t play an important role. meacham ([ ], p. ) seems to express the consensus : ‘note that the principal principle only plays a superficial role in the argument for elga’s proposal. the principal principle sets our credences in heads and tails on sunday to (½)/ (½). but the argument goes through equally well given any reason for (½)/(½) credences in heads and tails on sunday’. it isn’t prior relative to all evidence. it’s prior relative to learning how the coin landed. everettian confirmation and sleeping beauty by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ we can press the point by imagining a non-chancy variant of sleeping beauty. wilson provides us with such a variant, in which uncertainty about the result of a fair coin toss is replaced by uncertainty about the truth of a mathematical proposition. wilson has to say that the thirder arguments cannot be applied to the following case : mathematical sleeping beauty (msb): on sunday night beauty has credence ½ that fermat’s last theorem is true. she will be awakened on monday if the theorem is true, and on both monday and tuesday (again with her memories from monday erased) if the theorem is false. beauty knows all this. the puzzle is to say what credence beauty should have on monday in the proposition that fermat’s last theorem is true (call this proposition true.) i claim that making the hypothesis non-chancy doesn’t change anything—if you’re a thirder for chancy sleeping beauty cases, you should be a thirder for non-chancy sleeping beauty cases. however, before we get to the details, we can improve the example, as this variant has some unwanted complications. first, msb cannot be an ideal bayesian agent as ideal bayesian agents know all mathematical truths. second, in sleeping beauty there is a long-run frequency argument for i, based on the fact that, in the long run, there will be twice as many tails awakenings as heads awakenings. this argument cannot be used in msb, as the truth-value of a mathematical proposition can’t vary between wakings. wilson notes both worries and tries to use the second to drive a wedge between sleeping beauty (for which he endorses the i answer) and msb (for which he doesn’t). however, we can avoid both complications by letting the coin flip depend on a non-chancy contingent proposition. here’s a suggestion : non-chancy sleeping beauty: on sunday night, beauty has credence ½ that an even number of stars will be visible in total on monday night. she will be awakened on monday if there is an odd number, and on both monday and tuesday (again with her memories from monday erased) if there is an even number. beauty knows all this. the puzzle is to say what credence beauty should have on monday in the proposition that the number of stars is even. i claim that this still doesn’t change anything: if you are a thirder about the original case you should be a thirder about this one. wilson is committed to wilson pulls back from explicitly endorsing the halfer position for mathematical sleeping beauty. he just argues that ‘there are important disanalogies between msb and sb’ and ‘this provides reason to doubt whether our two cases [msb and sb] have a uniform solution [i]’ (wilson [forthcoming]). if you think this is chancy, feel free to substitute another proposition you think is non-chancy. darren bradley by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ being a thirder in the original sleeping beauty and a halfer in non-chancy sleeping beauty. and, i claim, this difference is inexplicable. the only differ- ence between the cases is what generated the priors, so we should not end up with a difference regarding confirmation. wilson does offer an argument that attempts to explain the difference between chancy and non-chancy sleeping beauty. he points out that the principal principle argument for i, which i described in section , cannot be applied to non-chancy sleeping beauty cases. and of course he’s right that it can’t be. however, this response is unsatisfactory for a couple of reasons. first, most thirder arguments do still apply to non-chancy sleeping beauty. wilson would have to hold that all of these fail, but elga’s succeeds. second, non-chancy sleeping beauty seems to show that, intuitively, chancy cases in which the principal principle can be applied should get the same verdict as non-chancy cases in which the principal principle cannot be applied. wilson has to explain away this intuition. merely pointing out that the principal principle cannot be applied to non-chancy cases doesn’t do this. and if we do apply the halfer answer in non-chancy sleeping beauty, we get problematic consequences of the kind that wilson is keen to avoid. the halfer position in non-chancy sleeping beauty means her credence in odd is still ½ after waking. and learning it’s monday then increases credence in odd to more than ½. so wilson is committed to the position that being told it’s monday is relevant to the number of stars that will be seen on monday night! this seems no better than the claim that being told it’s monday is relevant to the toss of a coin on monday night. we can also put pressure on the distinction wilson is trying to draw (between chancy and non-chancy processes) from the other direction. for example, imagine that god chose between st and eqm by flipping a chancy fair coin. indecisive god: god cannot decide between creating a world with st or one with eqm. so he creates a chancy fair coin and flips it: st if heads; eqm if tails. there is at least a prima facie case that each of the following thirder arguments can be extended to non-chancy sleeping beauty; see (arntzenius [ ]; dorr [ ]; draper and pust [ ], hitchcock [ ]; horgan [ ]; seminar [ ]; titelbaum [ ]; and weintraub [ ]). see lewis ([ ]) for details. here, with wilson, i ignore the ‘double-halfer response’ whereby credence would stay at ½. this is similar to wilson’s god’s gambling game (ggg). the (insignificant) difference is that in ggg, god is so indecisive that he flips a new coin every time a measurement is made to determine whether there will be more than one branch. wilson points out that we don’t get easy confirmation of ggg. but that isn’t the issue. wilson concedes that given ggg we would get easy confirmation of eqm (or its analogue for each branch). similarly, he should concede that given indecisive god, we would get easy confirmation of eqm. so he is committed to an everettian confirmation and sleeping beauty by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ the pp can be applied here, so wilson seems committed to the analogue of the thirder position, and easy confirmation of eqm. however, it’s inexplicable that whether god chose his design of the world by chance or had a clear intention all along could make such a difference to our epistemic position. so the distinction between outcomes generated by a chance process and outcomes generated by a non-chance process cannot do the work wilson wants it to. so i maintain that: (b) if you are a thirder in sleeping beauty, you are committed to easy confirmation of eqm. conclusion to sum up, i’ve defended two theses. first, that elga’s ([ ]) argument for being a thirder is unpersuasive and, second, that the presence of chance in sleeping beauty is irrelevant to whether being woken confirms heads or tails. let me briefly connect this to two broader issues. in the broader debate between thirders and halfers, i think there is no knock- down argument either way, but the most reasonable position still seems to me to be the halfer position of lewis ([ ]), defended in my ([ a]). there is also a broader debate about the extent of the analogy between sleeping beauty and eqm, and specifically about whether thirders are com- mitted to easy confirmation of eqm. wilson has pointed out a disanalogy between sleeping beauty and eqm, but i have argued that the disanalogy isn’t relevant to whether the agent receives confirmatory evidence. so the challenge stands: if thirders are to reject this easy evidence for eqm, they owe us an explanation of where the disanalogy lies. funding support for this project was provided by a psc-cuny award, jointly funded by the professional staff congress and the city university of new york. philosophy department the city college of new york convent ave, ny , usa bradleydarren@gmail.com inexplicable difference in confirmation depending on whether god picked st or eqm by a chancy or non-chancy process. wilson himself discusses other disanalogies pointed out by papineau and durà-vilà ([ a], [ b]) and peterson ([ ]), and argues that these disanalogies are not relevant; what wilson says here seems reasonable to me. thanks to alastair wilson and an anonymous referee for helpful comments on earlier drafts. darren bradley by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ references arntzenius, f. [ ]: ‘some problems for conditionalization and refection’, journal of philosophy, , pp. – . bradley, d. [ a]: ‘self-location is no problem for conditionalization’, synthese, , pp. – . bradley, d. [ b]: ‘confirmation in a branching world: the everett interpretation and sleeping beauty’, british journal for the philosophy of science, , pp. – . bradley, d. [ ]: ‘four problems about self-locating belief’, philosophical review, , pp. – . dorr, c. [ ]: ‘sleeping beauty: in defence of elga’, analysis, , pp. – . draper, k. and pust, j. [ ]: ‘diachronic dutch books and sleeping beauty’, synthese, , pp. – . elga, a. [ ]: ‘self-locating belief and the sleeping beauty problem’, analysis, , pp. – . hitchcock, c. [ ]: ‘beauty and the bets’, synthese, , pp. – . horgan, t. [ ]: ‘sleeping beauty awakened: new odds at the dawn of the new day’, analysis, , pp. – . lewis, d. [ ]: ‘a subjectivist’s guide to objective chance’, in r. jeffrey (ed.), studies in inductive logic and probability, berkeley: university of california press. lewis, d. [ ]: ‘sleeping beauty: reply to elga’, analysis, , pp. – . meacham, c. j. g. [ ]: ‘sleeping beauty and the dynamics of de se beliefs’, philosophical studies, , pp. – . papineau, d. and durà-vilà, v. [ a]: ‘a thirder and a everettian: a reply to lewis’s “quantum sleeping beauty” ’, analysis, , pp. – . papineau, d. and durà-vilà, v. [ b]: ‘reply to lewis: metaphysics versus epistemology’, analysis, , pp. – . peterson, d. [ ]: ‘qeauty and the books: a response to lewis’s quantum sleeping beauty problem’, synthese, , pp. – . seminar, o. [ ]: ‘an objectivist argument for thirdism’, analysis, , pp. – . titelbaum, m. g. [ ]: ‘the relevance of self-locating beliefs’, philosophical review, , pp. – . titelbaum, m. g. [ ]: ‘an embarrassment for double-halfers’, thought, , pp. – . weintraub, r. [ ]: ‘sleeping beauty: a simple solution’, analysis, , pp. – . wilson, a. [forthcoming]: ‘everettian confirmation and sleeping beauty’, british journal for the philosophy of science. everettian confirmation and sleeping beauty by guest on a pril , http://bjps.oxfordjournals.org/ d ow nloaded from http://bjps.oxfordjournals.org/ http://bjps.oxfordjournals.org/ lunfd /(nffl- ) october beauty’ conference summary paula eerola lund university, lund, sweden abstract investigations of b hadrons are expected to break new ground in measuring cp-violation effects. this series of beauty conferences, originating from the conference in liblice, has contributed significantly in developing ideas of cp-violation measurements using b hadrons and formulating and comparing critically the b-physics experiments. in the ’ conference in bled we saw the ripening of the field and the first fruit emerging – tevatron have produced beautiful b-physics results and more are expected to come with the next run, while the b- physics experiments at desy, slac and kek are starting their operation. the longer-term projects at lhc and tevatron have taken their shape and detailed prototyping work is going on. meanwhile, on the phenomenological side, there has been impressive theoretical progress in understanding deeper the ‘standard’ measurements and proposing new signatures. in this summary, i will highlight the status of the field as presented in the conference, concentrating on signatures, experiments, and r&d programmes. paula.eerola@quark.lu.se introduction cp violation is a key phenomenon in elementary particle physics for completing our present understanding of particles and interactions, formulated by the standard model of electroweak interactions, and searching for inconsistencies indicating effects from physics beyond the stan- dard model. investigations of b hadrons are expected to break new ground in measuring cp violation effects. cp violation can occur in any theory in which there are complex coefficients in the la- grangian. in the standard model (sm), the origin of the cp violation is the complex coupling of quarks to the higgs field. after the electroweak symmetry breaking, and after removing un- physical phases, one irremovable complex phase remains in the three-generation quark mixing matrix, the cabibbo-kobayashi-maskawa (ckm) matrix. the matrix is defined as: v =   vud vus vubvcd vcs vcb vtd vts vtb   =   − λ λ aλ (ρ − iη)−λ [ + a λ (ρ + iη)] − λ aλ aλ [ − (ρ + iη)( − λ ) ] −aλ [ ( − λ ) + λ (ρ + iη) ]   where the latter matrix is the wolfenstein approximation to order λ . λ is the cabibbo angle and is about . , a ' and ρ = . the complex elements are vub and vtd, if η = . in general, there are three sources of cp violation: cp violation in decay (‘direct cp violation’), where the decay amplitude for a process and its’ complex conjugate are not the same; cp violation in mixing (‘indirect cp violation’), which occurs when two neutral mass eigenstates are not cp eigenstates. cp violation can also originate from interference between direct decays and decays via mixing, if neutral b and b̄ mesons decay into the same final cp eigenstate. all these types of cp violation have been observed in kaon decays, most recent case being the direct cp violation, which the ktev experiment could observe, thus confirming the earlier results of na . preliminary results from na are in agreement with the ktev and na measurements (for a review, see ref. [ ] in these proceedings). kaon decays have provided a wealth of cp violation measurements, but they have not been able to probe the complex elements of the ckm matrix, and thus the sm origin of the cp violation. for this purpose, observing cp violation in b decays is mandatory. the b mesons are expected to exhibit large cp-violation effects in some (rare) decay modes, which probe the so-called unitarity triangle. unitarity of the ckm matrix defines triangle relations. the one which relates the first and the third column of the ckm matrix turns out to form a triangle in which all the sides are of the same order of magnitude: vudv ∗ ub + vcdv ∗ cb + vtdv ∗ tb = . when all the sides are divided by |vcdv ∗cb| ' aλ so that the base of the triangle is along the real axis and normalized to , the apex of the triangle is located at (ρ̄, η̄), where ρ̄ = ρ( −λ / ) and η̄ = η( − λ / ). one side of the triangle is related to v ∗ub, vudv ∗ub/vcdv ∗cb ' . , and the other side is related to vtd,vtdv ∗ tb/vcdv ∗ cb ∼ . the angles α, β and γ are defined in fig. . another triangle can be defined by combining the first and the third rows of the ckm matrix, figure : unitarity triangle vudv ∗ ub + vcdv ∗ cb + vtdv ∗ tb = . figure : unitarity triangle vtbv ∗ ub + vtsv ∗ us + vtdv ∗ ud = . and it is shown in fig. . it probes the same two ckm matrix elements as the ‘standard’ unitarity triangle, and it’s angles γ′ and δγ can be measured. when neutral b and b̄ mesons decay into the same final cp eigenstate, the cp violation can in general have contributions both from direct cp violation and from interference between direct and mixed decays. in this case, the time-dependent cp asymmetry can be expressed as follows: acp (t) = Γ(b q(t) → f) − Γ(b̄ q(t) → f) Γ(b q(t) → f) + Γ(b̄ q(t) → f) = adircp (b q → f) cos(∆mqt) + aintcp (b q → f) sin(∆mqt), where adircp is the direct cp-violation amplitude and a int cp is the mixing-induced cp-violation amplitude. subscript q indicates a d- or an s-quark, and ∆mq is the mass difference of the b q eigenstates. here it is assumed that there is no width difference of the b q eigenstates, which is valid for b d mesons. for b s , however, the width difference can be sizeable, % or so, and the formula has to be modified accordingly. if the decay of a neutral b meson is dominated by a single ckm amplitude, the mixing- induced cp-violation amplitude is aintcp = Λ sin(φm − φd). the mixing phase φm is + β in case of b d mesons and − δγ for b s mesons, and Λ is the cp eigenvalue of the final state. the cp-violating weak decay phase φd is zero for dominant b̄ → c̄cs(d) amplitudes, and − γ for dominant b̄ → ūud(s) amplitudes. measurement methods in the past few years, much theoretical progress has been made in understanding the different sources of cp violation, and analysis methods have been developed accordingly. here, the measurement methods of angles β, α and γ are described, with an emphasis on the proposed new modes. these issues are described in more detail in the theoretical contributions to this conference, see [ ], [ ] and [ ]. analysis methods are also addressed briefly. . angle β the angle β can be measured cleanly using the decays b d → j/ψk s. this decay is dominated by the decay amplitude b̄ → c̄cs, since the penguins are expected to be small and moreover, they have the same weak phase as the tree-level decays. therefore, the direct cp-violation contribution is very small and can be neglected, i.e. adircp ' , and the mixing-induced cp- violation amplitude is aintcp = − sin β. . angle α the angle α can be measured with the decay b d → π+π−. this decay has, however, contribu- tions from both penguin and tree decay graphs, and recent cleo measurements of b → ππ, kπ indicate that the penguins play a significant role. if there were no penguin contributions present, the mixing-induced cp-violation amplitude would be aintcp = sin( β + γ) = − sin α, assuming the sm triangle relation α + β + γ = π. including the penguin contributions the amplitudes can be written in the form: adircp = ap at sin δ sin α, aintcp = − sin α − ap at cos δ cos α sin α, where ap /at is the ratio of the penguin and tree amplitudes, and δ is the strong phase difference between the amplitudes. if the ratio ap /at can be predicted accurately with the help of additional branching ratio measurements, α and δ can be extracted from the measured asymmetry. there is an alternative proposal of measuring the angle α using decays b d → ρπ [ ]. this option has been studied recently for example by the babar collaboration [ ]. another way of attacking the problem is to use isospin relations between the decays b d → π+π−, b d → π π , b+ → π+π and the charge conjugated modes [ ]. in this way the angle α could be measured unambiguously. the decay mode b d → π π is, however, predicted to have a branching ratio of − or less, which makes the method experimentally difficult. . angle γ the angle γ is the most difficult to measure, since there is no both experimentally feasible and theoretically clean decay of a b to a cp eigenstate, which could be used (the equivalent channel to b d → j/ψk s and b d → π+π− would be b s → ρk s). there has been, however, a considerable amount of theoretical activity recently to find new methods of probing the angle γ. a method of measuring the angle γ is to measure the decay time distributions of b s → d±s k∓ and the charge conjugated modes [ ]. here cp violation is due to interference of direct and mixed decays. tagging is obviously needed to distinguish b s and b̄ s . fitting the two decay asymmetries vs. decay time gives γ − δγ and δ, where δ is the strong phase, and δγ is the phase of vts. another method of measuring the angle γ is to consider the decays b d → d cpk∗, b d → d̄ k∗, b d → d k∗ and their charge conjugated modes [ ]. the amplitudes of these decays are related by two triangles in the complex plane. the triangles differ in the length of one side only, and an angle between the two triangles is γ. in addition to the weak phase, there is a dependence on a strong phase difference δ, but it can be extracted from the measurements. similar relations exist for the charged b decays: b+ → d cpk+, b+ → d̄ k+, b d → d k+ and charge conju- gated modes [ ]. these decays are self-tagging, so no external tag is required. on the other hand, these decays are purely hadronic, requiring a hadronic first level trigger. furthermore, some of the decay modes have small branching ratios, which make the measurements difficult, in particular for babar and belle. the decay b d → d(∗)±π∓has been proposed already a while ago for angle γ measurement [ ]. even if these decays are not decays to cp eigenstates, both b d and b̄ d can decay to the same final state, leading to interference between mixing and decay, which measures sin( β +γ), and a strong phase difference δ. when the angle β will have been measured accurately in the b d → j/ψk s decays, the angle γ can be extracted. these decays were first payed little attention due to problems with statistics – even if the branching fractions are not that small, of the order of − , one of the decay paths is doubly cabibbo-suppressed and therefore the cp-violating effects are tiny. furthermore, the reconstruction efficiency is small for fully reconstructed final states. the channel was, however, recently re-considered by babar [ ], for which the channel would provide an access to the angle γ since b d decays are involved. they realized that the statistics can be improved considerably by using inclusive reconstruction. the channel has also been studied by lhcb collaboration with promising results, indicating an accuracy of four degrees for the angle γ after five years of data-taking [ ]. a lot of theoretical effort has been put recently in learning how to extract angle γ, or set limits to γ, using various combinations of kπ, ππ, and kk final states. here these modes are addressed only briefly, more details can be found elsewhere in these proceedings [ ], [ ], [ ]. three different combinations of these decays have been proposed to set limits to the angle γ: b± → π±k and b d → π∓k± [ ], b± → π±k and b± → π k± [ ], [ ], and b d → π k and b d → π∓k± [ ]. the strategies are based on flavour-symmetry arguments, although the theoretical understanding of the hadronic final state interaction effects is poor at the moment. the strategies of simultaneously determining β and γ using decays b d → π+π− and b s → k+k− was also discussed in this conference [ ]; using this combination of decays is theoretically cleaner, since the theoretical accuracy is only limited by u-spin breaking effects (interchanging d and s-quarks). similar arguments were presented for decays b s(d) → j/ψk s and b d(s) → d + d(s) d− d(s) . . measurements of b s -mesons the b s -meson mixing parameter ∆ms has not been measured yet, due to the rapid oscillations of b s -mesons. the b s -meson mixing gives an important constraint to the unitarity triangle. one side of the triangle is proportional to vtd, which is related to the b d-meson mixing parameter ∆md. despite of the fact that there is a rather precise measurement of ∆md, several hadronic uncertainties limit the precision of the vtd measurement. in the ratio ∆ms/∆md, on the other hand, many common factors such as qcd corrections and dependence on the top quark mass cancel, and a more accurate estimation of vtd is possible. the ratio can be written as ∆ms ∆md = m(bs) m(bd) b(bs)f (bs) b(bd)f (bd) |v ∗tbvts| |v ∗tbvtd| , where m(bq) are the b-meson masses, b(bq) are the bag parameters, and f(bq) the b- meson form factors. in order to measure the b s -mixing, the decay time has to be measured accurately, and the flavour of the b has to be tagged both at the decay time (tagged by the observed decay itself) and at production. to tag the flavour of the b at the production time, an external tag has to be used – these tagging methods are discussed in more detail in the following section. the asymmetry between mixed and non-mixed decays is: a(t) = d cos(∆mst) cosh(∆Γst/ ) , where the dilution factor d comes from finite proper time resolution, mistags, and back- ground. ∆Γs = Γh − Γl is the width difference between the b s mass eigenstates bh and bl. oscillations are most often searched for using methods based on fitting the amplitude of the oscillatory term, keeping the ∆ms fixed, and repeating the fit with different values of ∆ms [ ]. this method has the advantage that results from different experiments can be easily combined. the decay channel b s → j/ψφ is very useful for extracting various, as yet unmeasured or poorly measured parameters of the b s mesons. furthermore, the decay channel is experimen- tally an easy one since it can be triggered and reconstructed cleanly. the b s decay proper time and the angular distributions of the secondary particles can be used for extracting ∆Γs, Γs = (Γh +Γl)/ , and cp amplitudes a|| and at describing the decays to cp-even and cp-odd configurations. the angular analysis is sensitive to the strong phase differences between the amplitudes as well. all these parameters can measured by using untagged samples. the weak phase of the decay b s → j/ψφ is proportional to δγ, and it is very small in the sm. furthermore, the weak phase measurement requires an external tag. nevertheless, this decay mode can be used for constraining the angle γ together with the various other decay modes. in particular, larger than expected cp violation would indicate that processes beyond the sm are involved. . analysis methods experimental analysis methods have been improved considerably over the years. in particu- lar, many new or complementary tagging methods have been established; in addition to the traditional opposite-side lepton tagging and kaon tagging, hadronic tagging methods such as same-side pion tagging, same- or opposite side jet-charge tagging, and vertex charge tagging have shown their power in increasing the statistics significantly. the cdf experiment, for example, has demonstrated that the poorer purity of the hadronic tags is compensated by the bigger efficiency, and the tagging quality factor �d (� = efficiency, d = dilution) is roughly the same for the opposite side lepton tags ( . %) as for the same-side hadron tags ( . %) and the jet-charge tags ( . %) [ ]. the combined use of these methods has allowed the experiments at lep, slc and tevatron to push the limits of their b-physics programmes by improving considerably the tagging efficiency. measurements of ∆md, limits on the b s -mixing, and the asymmetry measurement of tagged b d → j/ψk s decays in particular, are examples of results unforeseen some years ago. in the early days of planning cp-violation measurements using b-decays, expected perfor- mance was evaluated by simply estimating event rates. more thorough analysis methods are needed to extract all the available information. for example, time-dependent measurement of cp-asymmetries is almost mandatory, not only to prove the expected time-dependence of the asymmetry, but also to help in distinguishing the signal from backgrounds with different time- dependence. for mixing measurements, amplitude fits have provided a useful platform at lep, slc and tevatron to extract and combine experimental limits. angular analyses will have to be utilized for channels in which the b-meson decays into spin-carrying non-stable particles, such as in the case of b s → j/ψφ decay. present results . direct measurement of angle β the cdf limit on angle β was reported in this conference [ ]. the b d → j/ψk s sample consisted of about events in which both muons from j/ψ are within the svx acceptance, and about events with one or no muons reconstructed in the svx. data were collected at the tevatron run i, and consisted of an integrated luminosity of pb− . the events with both muons in the svx had a precise lifetime information, and a time-dependent analysis could be performed. the additional sample of events had imprecise lifetime information. a time-averaged analysis could be performed, however, improving the precision of the combined measurement. soft leptons, jet-charge, and same-side hadrons were used for tagging, each providing a similar tagging quality of about . %. the combined tagging quality factor was ( . ± . )%, accounting for correlations and double tags. the tagging efficiency and dilution factors were measured using an independent sample of b+ → j/ψk+ decays, and a b → `d(∗)x sample suitably scaled to account for momentum differences. the result of the full unbinned maximum likelihood fit was: sin β = . + . − . . the measured asymmetry is shown in fig. . interpreting the measurement as a limit to sin β, cdf quote < sin β < at % cl using the feldman-cousins frequentist approach, and at % cl using the bayesian approach. ct (cm) tr u e as ym m et ry ∆m floating ∆m fixed - sin β - - . . . . . figure : cdf measurement of asymmetry in b d → j/ψk s decays [ ]. the opal experiment at lep performed the first exploratory search for cp asymmetry in b d → j/ψk s decays, using a sample of reconstructed events, out of which events were estimated to be background [ ]. the measurement yielded sin β = . + . − . ± . . . precision measurements the ckm matrix element ratios |vub/vcb| and |vtd/vcb| are related to the lengths of the sides of the unitarity triangle. in this conference, updated results were presented by cleo on |vcb| and |vub/vcb| [ ], yielding |vcb| = ( . ± . ± . ± . ) · − , |vub| = ( . ± . + . − . ± . ) · − , where the last error is the theoretical uncertainty. the lep experiments have made progress in measuring these matrix elements in the lep data, with different systematical uncertain- ties from cleo. new results on |vcb| were presented in this conference from analyses using exclusively reconstructed final states, see ref. [ ]; the errors of individual experiments are approaching the ones from cleo. averaging over the lep results, including both the inclu- sive |vcb| determinations from lifetime and branching ratio measurements and the exclusive measurements, yields [ ]: |vcb| = ( . ± . ) · − . the lep average for |vub| reported in this conference was: |vub| = ( . + . − . ± . ) · − , where the last error is the theoretical uncertainty. the matrix element vtd is at the moment constrained by the ∆md measurements and the ∆ms limits. the b d meson oscillation frequency ∆md has been measured accurately by the lep experiments, sld and cdf, while the Υ( s) experiments provide time-integrated mixing measurements. the lep average value reported in this conference yields a value of ∆md = ( . ± . ) ps− [ ], while the world average including lep, sld, cdf and Υ( s) experiments is ∆md = ( . ± . ) ps− [ ]. the combined lep % cl limit for the b s meson oscillation frequency ∆ms is . ps − , while the sensitivity is . ps− . the world average limit by the lep experiments, sld, and cdf is . ps− , and the sensitivity is at . ps− [ ]. lifetimes of b+, b d, b s , bc and b-baryons were reported by cdf and the lep experiments. the combined results were [ ], [ ]: τ(b+) = ( . ± . ) ps, τ(b d) = ( . ± . ) ps, τ(b s ) = ( . ± . ) ps, τ(bc) = ( . ± . ) ps (cdf), τ(Λb) = ( . ± . ) ps, τ(Ξ b) = ( . + . − . ) ps (aleph, delphi). very recently, new branching ratio measurements were presented by cleo [ ]. the mea- sured branching ratio for the decay b d → π+π−, br(b d → π+π−) = ( . + . − . ± . ) · − , indi- cates difficulties for the angle α measurements, in particular at the e+e− b-factories. the much larger branching ratio for the decay b d → k−π+, br(b d → k−π+) = ( . + . − . ± . ) · − , suggests large penguin contributions. cleo is also probing the way of constraining the angle γ by comparing the rates for charged and neutral b decays to kπ using the neubert-rosner analysis. cleo results [ ] favour γ > ◦, a result which would be in contradiction with the unitarity triangle apex region allowed by the ∆ms limit. . . . . - - . - . - . - . . . . . figure : unitarity triangle constraints from present precision data (from ref. [ ]). cdf presented complementary results on the b s frontier [ ]. using a sample of about inclusively reconstructed b s → `dsx decays, a two-component lifetime fit of the form exp(−Γht) + exp(−Γlt) was used to measure the width difference ∆Γs, yielding a result ∆Γs/Γs = . + . − . . interpreted as a limit, the measurement yielded ∆Γs/Γs < . at % cl. in the sm, the width difference ∆Γs is related to ∆ms by a hadronic scale factor. the cdf limit on upper limit on ∆Γs gives thus an upper limit of ps − to ∆ms. cdf presented also polarisation measurements. the measurement of the polarisation in b d → j/ψk ∗ used about events, similar to cleo. the polarisation measurement of b s → j/ψφ used about events – it is the first polarisation measurement of its kind, al- beit limited by the statistics. with a larger statistics, ∆Γs can be measured together with the cp-even and cp-odd amplitudes a|| and at , along with the strong phases, as discussed in section . . the precision data on |vcb|, |vub/vcb| and ∆md, the ∆ms limit, and �k from kaon ex- periments, combined with estimates on hadronic factors from mass measurements and lattice calculations, can be used to constrain the unitarity triangle. various such fits have been per- formed, see for example refs. [ ], [ ] and [ ]. theoretical errors for the vub are already limiting the bound from |vub/vcb|. the direct measurement of angle β is completely consistent with the region allowed by the indirect measurements, but the present accuracy of the sin β measurement does not improve the overall fit. in ref. [ ], the following ranges for the angles α, β and γ are quoted: sin β = . + . − . , sin α = − . + . − . , γ = ( . + . − . ) ◦. the region limited in the complex space by the combined fit is shown in fig. . the hera-b experiment at desy ring imaging cherenkov counter mrad mrad mrad magnet si-strip vertex detector calorimeter trd muon detector target wires m photon detector planar mirrors top view side view proton beam electron beam proton beam electron beam spherical mirrors vertex vessel inner / outer tracker beam pipe c f figure : the hera-b detector layout. experiments embarking on data taking the timing of the conference was quite exciting, since there were several b-experiments getting ready for data-taking. this conference was the first one to see collision events from babar and belle. hera-b experiment is expected to be fully commissioned by end of , and the upgraded cdf and d experiments will re-start at the high-luminosity tevatron around mid- . . hera-b hera-b experiment at desy is a fixed-target b-experiment, operating at the gev proton ring hera [ ]. the detector layout is shown in fig. . the experiment is challenging due to the small ratio of bb̄-to-total cross-section, about − , resulting in difficult trigger and target requirements. at the center-of-mass energy of about gev, the bb̄ cross-section is about nb, albeit with large uncertainties. in order to obtain a competitive number of signal events in the decay mode b d → j/ψk s ( reconstructed events in a year), four interactions per bunch crossing are needed, resulting in an interaction rate of mhz. this corresponds to an integrated luminosity of about fb− in a year. the requirements to the trigger, and the high radiation dose that some of the hera-b subdetectors will have to stand, are comparable to the conditions at lhc. to maximise the interaction rate while minimising the interference to the ep-operation at hera, the target was designed to consist of two sets of four wires placed at the beam halo, located at a distance of four to ten standard deviations from the beam [ ]. the target has been in continuous operation since , and the main requirements have been achieved. the hera-b trigger consists of three levels [ ]. the first level trigger searches for two lepton candidates with an invariant mass compatible with a j/ψ, or two high-pt hadrons compatible with originating from a b-meson. the track seeds originate from the muon pad chambers, the electromagnetic calorimeter or from the high-pt chambers. a fast hardware tracking is then performed, in which regions of interest are scanned in the upstream detector layers using a kalman filter-type method. the track candidates are refined in the second level, while the third level trigger uses data outside regions of interest as well. the final output level (level ) reconstructs and classifies the events without any further rate reduction. many of the sub-detectors are completed and entering the full commissioning phase: the vertex detector (vds) [ ], the ring imaging cherenkov counter (rich) [ ], electromagnetic calorimeter (ecal) [ ], the tdr and the muon detector [ ]. the data-acquisition system has been running stable for several months, and the commissioning of the first level trigger (flt) is starting. some hera-b subdetectors have been suffering from technological problems to fulfil the requirements of operating in a high-radiation environment. the anode aging and malter effect problems with the outer tracker, which consists of honeycomb drift-chambers, seem to have been solved by cathode au-coating, proper gas choice and careful validation of materials as well as manufacturing procedures. after applying these measures, the detectors have been proven to survive in a hadronic environment an equivalent radiation dose of two integrated hera-b years [ ]. the mass production is progressing in a rapid pace, and all the chambers are planned to be installed by november . the inner tracker is using microstrip gas chambers (msgcs). original problems with sparking were solved by adding gas electron multipliers (gems) into the drift space. even though the chambers still show a gain variation as a function of the accumulated charge, the detectors have been considered as adequate for hera-b [ ]. the mass production is proceeding and the whole inner tracker is expected to be completed by the end of . . e+e− b-factory experiments the babar experiment at slac and the belle experiment at kek are asymmetric e+e− collider experiments, collecting bb̄ pairs produced in Υ( s) decays. the production cross- section of bb̄ pairs is about nb. both experiments took their first data just prior to this conference, and exciting first event views were shown. in babar, the gev electron and . gev positron beams, circulating in the double pepii ring, are brought to collide with a zero-angle crossing, which requires strong magnets within the interaction region to deflect the beams between bunches. the nominal luminosity is · cm− s− – the nominal one year data corresponds thus to fb− . the babar detector has to fulfil special requirements on its’ tracking parts due to the asymmetric collisions: since the boost is along the beam axis, the difference of the decay times of the two b-mesons is measured by the difference in the z component of the vertex separation. furthermore, the pt- range of the final state particles is quite low, between mev and gev. the tracking system consists of a silicon vertex tracker (svt) and a drift chamber (dch), immersed in a . t solenoidal field. the charged hadrons are identified in the detector for internally reflected cherenkov light (dirc), which is a novel technology using quartz bars both for producing the cherenkov light and as light guides [ ]. the electromagnetic calorimeter is a csi calorimeter, and outside the emc the instrumented flux return (ifr) is used for muon identification and for enhancing k l detection. the collaboration is using software written entirely in c++. babar started taking colliding beam data may th [ ]. by june th , time of the conference, pb− were collected on tape and first hadronic events were shown. an example of a reconstructed hadronic event is shown in fig. . mass peaks for k s → π+π− with a width of mev (loose vertex pointing requirements, no particle id) and π → γγ were reconstructed and shown. in addition, · cosmics had been collected prior to the colliding beam data taking. all subsystems were operational and complete apart from a fraction of the dirc bars. since the conference, the exclusive b reconstruction was under way and the first b d → j/ψk s candidates were identified. figure : a hadronic event reconstructed in babar. the belle experiment is operating at the kekb ring, which produces collisions between gev electron and . gev positron beams. the ring design includes several novel features, such as a finite-angle beam crossing, which has the advantage that there is no need for strong magnets within the interaction region, making the design of the tracker detectors easier. the nominal design luminosity is · cm− s− . if bunch-bunch instabilities appear, a crab- crossing scheme, in which the bunches are tilted so that they collide head-on despite of the finite crossing angle, will be a possible solution. the tracking system consists of a silicon vertex detector (svd) and a central drift chamber (cdc) in a . t solenoidal field. the charged hadrons are identified by using a time-of-flight (tof) counter and an aerogel cherenkov counter (acc). the electromagnetic calorimeter consists of csi crystals and the instrumented iron yoke serves as a muon and k l detector. the first collision events were observed in june st [ ]. by june th , an integrated luminosity of about nb− was collected. in this conference, reconstructed j/ψ → e+e− and µµ events were shown, as well as mass peaks for k s → π+π− and for π → γγ. the k s mass resolution was . mev. the resolution for the π was about . mev, with eγ > mev. an example of a reconstructed hadronic event is shown in fig. . after the conference, till august th , a total of pb− of data was recorded by belle, with the accelerator reaching a peak luminosity of . · cm− s− . most of the data were taken on the Υ( s) peak. z x z y cm belle cm belle µ (j/ψ)+ µ−µ (j/ψ)− µ (j/ψ)+ µ (j/ψ)− µ− mm ∆z= µm k+ k+ cm belle cm belle(a) (b) (c) (d) figure : a hadronic event reconstructed in belle. the cleoiii detector is an upgrade of the cleo detector at cesr to achieve luminosities in excess of cm− s− [ ]. cesr is a symmetric e+e− collider operating at the Υ( s) peak. the main features of the upgrade concerns the particle identification and tracking [ ]. charged hadron identification will be enhanced with a rich detector. the tracking system had to be rebuilt due to the reduced space available – the new tracker will consists of a new drift chamber, and a silicon vertex detector, whose main function is in providing precision tracking. the cleoiii experiment will start operating during , and it is aiming at a wide range of b-physics accessible with rate measurements. . upgraded cdf and d the cdf and d experiments at the tevatron pp̄ collider are being upgraded for the high- luminosity run (runii). the runii is scheduled to begin in the summer of , with an increased luminosity resulting from many improvements in the collider, the main one being the replacement of the old main ring with the new main injector. the crossing rate will be ns for bunches, corresponding to a typical luminosity of . · cm− s− and a peak luminosity of · cm− s− . at the peak luminosity, the average number of interactions per crossing is two. the design goal is to collect an integrated luminosity of fb− in about two years of running. an increase of the collision energy from . tev to . tev is planned as well, driven by the % enhancement in the tt̄ yield. at tevatron, the bb̄ production cross-section is about µb. the ratio of the bb̄-to-total cross-section is about − , requiring efficient trigger strategies. the cdf detector will have many new features to improve the resolution and radiation tolerance, and to cope with the shorter crossing rate [ ]. there will be a new seven-layer radiation hard silicon vertex and tracking system, extending between radii . cm to cm ( . cm with the innermost layer , beyond the baseline detector). the central outer tracker, cot, will be new as well, since the available radial space will be less, and the maximum drift time has to be shorter than the crossing time. the calorimeters beyond |η| > will be replaced with a scintillating tile calorimeter, and a new muon system will be built to cover the region . < |η| < . . the trigger and data acquisition system will be fully pipelined. fast tracking will be available at level- , allowing for an all-hadronic b-decay trigger. in the level- , it will be possible to trigger on tracks with a high impact-parameter. beyond the baseline design, a tof detector has been recommended to enhance particle identification at very low momenta ( . gev < pt < . gev). the d detector is undergoing a major upgrade, driven by both new physics goals and changes in the collider [ ]. the whole tracking system is new, consisting of a central fiber tracker (cft) and a silicon microstrip tracker (smt) in a t solenoidal field. the elec- tron identification is enhanced by adding preshower detectors in front of the electromagnetic calorimeter, and the muon system has been upgraded significantly. to cope with the shorter bunch spacing while covering the physics goals, the front-end electronics, trigger and data- acquisition systems have been largely re-designed. the level- b-decay triggers are based on soft leptons – hadron or vertex triggers are not considered. in addition to the single and di-muon triggers, e+e− pairs can be triggered on by matching either a track element in the outermost cft layers (pt threshold . gev) and a calorimeter cluster (et threshold . gev), or a preshower cluster (threshold - mips) and a calorimeter cluster. experiments being designed and constructed by the year , various experiments will have explored the unitarity triangle. it is likely that the angle β will have been measured with a fair precision, σ(sin β)= . or so. sides of the unitarity triangle will have been measured: vub, possibly still limited by hadronic uncertainties, and vtd from mixing measurements of both bd and bs. it is still quite possible that for the angle α, there is only a low statistics measurement, with theoretical uncertainties, and for the angle γ, there is no accurate measurement or even no direct measurement at all. considering the allowed region for the apex of the unitarity triangle, the angle β is actually not constraining it significantly, but it is the angle γ which is significantly reducing the size of the allowed region and thus placing a stringent test to the sm. therefore, the next generation of experiments at lhc and at tevatron are needed for full investigation of cp violation in order to over-constrain the ckm matrix via high statistics measurements, complemented by theoretically clean channels. . dedicated b-physics experiments lhcb and btev lhcb is a forward single-arm spectrometer at lhc with efficient trigger, good particle iden- tification and good momentum resolution [ ], [ ]. the lhcb detector layout is shown in fig. . the main components of the detector are a vertex detector inside the beam vacuum, a tracking system with a dipole magnet, two rich counters to identify charged hadrons over a sufficiently large momentum range, calorimeters, and a muon system. the angular coverage is from mrad to mrad, corresponding to about three units in pseudo-rapidity. the single- arm geometry exploits the fact that the bb̄ system is boosted along the beam, and thus the b and the b̄ mesons are highly correlated in pseudo-rapidity. figure : the lhcb detector layout. at lhc, the total bb̄ cross-section is about µb, with an uncertainty of a factor of two or more. the fraction of bb̄-to-total cross-section is of order − . at lhcb, the lhc beam is ‘detuned’ to produce a constant luminosity of · cm− s− . this luminosity is chosen to optimize the fraction of single pp interactions per bunch crossing to minimize the radiation damage, and to minimize the detector occupancy to make pattern recognition easier. at the luminosity of · cm− s− , the fraction of bunches with a single pp interaction is about %. at lhcb, the level- trigger selects first single pp interactions by applying a pile-up veto, obtained from two dedicated si-disks. single interactions are then passed on to be processed by pt or et single track triggers, provided by muon chambers for muons ( % of events), ecal for electrons/photons ( %), or ecal and hcal for hadrons ( %). the rate is reduced from mhz to mhz. the level- trigger is based on topological identification of secondary vertices. track ele- ments are found in the si-disks, the primary vertex is reconstructed, and secondary vertices are formed by using large impact parameter tracks. the rate is expected to be reduced from mhz to khz. the higher level triggers (levels two and three) will consist of software algorithms running on farms of commercial computers. the higher level triggers will have to reject uninteresting bb̄ events in addition to non-b events. the target rate for data recording is hz. btev is a forward two-arm spectrometer proposed for tevatron [ ], [ ]. the btev detector layout is shown in fig. . the detector is planned to have a good particle identification, and in particular, it is relying on a secondary vertex level- trigger by using track vectors from pixel triplets. the main components of the detector are a pixel vertex detector located inside a dipole magnet on the interaction region, forward trackers, rich counters, high-resolution pbwo electromagnetic calorimeters, hadron absorbers and muon system consisting of toroid spectrometers. the angular coverage is up to mrad on both arms. the total bb̄ cross-section is a factor of five less than at lhc; however, there are many compensating factors working in favour of btev. the two-arm solutions brings an obvious factor of two. another factor of two comes from running with two interactions per crossing, which is possible at tevatron due to the long luminous region which makes it easier to separate different primary vertices, and the longer bunch spacing ( ns). furthermore, the smaller boost of b hadrons increases the track angles with respect to the beam pipe, thus reducing the radiation damage and making the pattern recognition easier. the smaller boost also enables btev to manage with a single rich detector, whereas lhcb has to use two separate riches to cover the whole dynamical range. the overall length of the detector can be made shorter as well. a vertex trigger at the level- is naturally very desirable to trigger efficiently on purely hadronic final states. to achieve this, the tracking/vertex detector design has to be tied closely to the trigger design. the baseline is to use pixel triplets in a dipole field, thus forming track vec- tors. primary vertex can be formed from these track vectors, and large impact parameter tracks can be searched for. preliminary studies indicate that requiring at least two tracks detached by more the four standard deviations from the primary vertex, only % of the beam crossings are triggered, while an efficiency from % to % can be achieved for the most commonly studied hadronic decays (b → h+h−, b s → dsk, b− → d k−, b− → k sπ−, b d → j/ψk s, b d → j/ψk∗, b → k∗γ ) [ ]. . general purpose experiments atlas and cms at lhc the general purpose experiments atlas and cms at lhc are high-pt central collider ex- periments, designed primarily for heavy particle searches, but with a significant capacity for precision physics, in particular in the first years of lhc operation with a nominal ‘low’ lumi- nosity of · cm− s− , giving an integrated luminosity of fb− per year [ ], [ ], [ ]. the limiting factor for the maximum luminosity for b physics is the level- trigger output rate, rather than the offline reconstruction capability. some channels such as rare decays of the type b → µµ(x) are particularly suitable for atlas and cms since they are self-triggering, and the high-luminosity data of lhc can be used as well. the angular coverage of the tracking systems of these detectors is about five units in pseudo- figure : the btev detector layout. rapidity. since the bb̄ production cross-section is roughly flat in pseudo-rapidity, the production rate is as high in the central as in the forward region. on the other hand, the small boost of central b quarks, and the consequent lack of angular correlation between the b and b̄, make triggering of b-hadron final states difficult. the lack of single hadron triggers with sufficiently low pt at the lowest trigger level, and the poor charged hadron identification are the most obvious handicaps of the general purpose experiments with respect to dedicated b-physics experiments. both atlas and cms have powerful muon systems which are capable of triggering on single low-pt muons at the lowest trigger level – the threshold for a single muon trigger is gev for atlas and gev for cms. the single muon trigger makes the backbone of the b-physics triggers. cms can use a lower threshold of - gev for the level- muon if other signals are available in addition to the muon. after applying the trigger level- acceptance, the number of triggered bb̄ events is typically few times per year. at the level- and at higher trigger levels, the triggers are designed to select specific b-decay channels. atlas and cms have pixel detectors as the detector element closest to the interaction point, thus providing a good vertex resolution. the large tracking systems enable efficient charged particle reconstruction. in addition, atlas has the capability for identifying low-pt electrons (pt > . gev) by using the transition radiation in the trt, while both experiments can use their electromagnetic calorimeters for identifying soft electrons at somewhat higher pt. the use of the atlas trt for π/k separation has been investigated recently [ ]. the results are very encouraging and would enhance greatly the analysis of the two-hadron decays of b-mesons, however, the results are still to be confirmed at beam tests. detector r&d, prototypes and running experience . targets and beams in this conference, first running experience was reported on the pepii and kekb asymmetric e+e − beam operation [ ], [ ]. at kekb, synchrotron light background from the whole ring was found to be a significant issue for the belle operation, requiring further work. at pepii, the main source of babar background was found to be lost particles, coming from local bremsstrahlung, and local or distant coulomb scattering. hera-b experiment has already several years experience on the wire target operation [ ]. two sets of four wires are placed at the beam halo, located at a distance of four to ten standard deviations from the beam. the distance is not constant, but as the beam intensity drops, the wires are brought continuously closer to the beam core to keep a constant interaction rate. even though the proton beam lifetime is reduced due to the fact that the wire target operation is consuming between and ma/h of the proton current, the luminosity and the background conditions to the other hera experiments are not affected. a reliable target steering and stable operation have been achieved. . multilevel triggering apart from the e+e− b-experiments, the trigger is a vital issue since the fraction of b-events varies from about % (lhc) down to − (hera-b). moreover, since the branching fractions of interesting final states are typically small, the experiments have to have interaction rates o( mhz) or more. all the experiments use a multilevel triggering scheme. some experiments use a pre-trigger (level- ) either to discard empty crossings (hera-b), or to make a pile-up veto (lhcb). the lowest level physics trigger (level- ) is searching for high-pt leptons or hadrons. this is achieved in most experiments by using fast trigger detectors stand-alone. only hera-b will use tracking in level- to confirm the high-pt hadron signals. btev is the only experiment which is planning to use an event topology trigger at level- , searching for displaced vertices. at the higher trigger levels, data is kept in pipelines for online event processing. data storage is expected to operate at a hz rate, apart from btev which is planning to compress the data online, and to write out only data summary information. . tracking and vertexing microvertex detectors, located as close to the primary vertex as practically possible, are crucial for precise secondary vertex measurements. in e+e− experiments at the Υ( s), the vertex detectors operate also as stand-alone tracking devices for very low-momentum particles. in forward spectrometer geometries, retractable detector disks are located inside the beam vacuum vessel, while in central experiments the closest detector layer can be placed just outside the beam pipe. technologies employed are either si-strip detectors or si-pixels. radiation hardness is an issue even for the vertex detectors in e+e− experiments – for example the babar vertex detector is foreseen to tolerate a . kgy dose per year, thus guaranteeing a -year operation [ ]. for comparison, at hera-b, in the detector area closest to the beam, the maximum dose per year is kgy, and it is foreseen that the silicon detectors will be exchanged once per year [ ]. tracking systems are facing unforeseen operational requirements with the high particle rates. progress has been made in solving detector physics and chemistry problems at high particle rates. hera-b experience with the honeycomb drift chambers has given valuable lessons on the careful choice of materials, glues and gases [ ]. the problems at hera-b with a new device, msgc, are not that surprising since these detectors have never been used before in high-energy physics experiments. while the hera-b experiment has equipped their msgcs with gems [ ], thus achieving satisfactory performance, the cms experiment is studying using advanced passivation on their msgcs [ ]. in this method, a strip of dielectric material is deposited over all the cathode edges to prevent electron extraction by the high electric field at the strip edges. using this method, together with high surface resistivity and narrow anodes, the cms prototype detectors have been proven to operate in an lhc-like radiation environment. the possibility for de/dx measurements has proven to be a valuable asset, if no other particle identification method is available and if the momentum spectrum of particles is suit- able. it has been used in e+e− experiments (cleo, lep experiments) as well as in hadronic experiments (cdf). . calorimetry and muons the electromagnetic calorimeters are used for triggering electrons and photons, and for recon- structing electrons, photons, and π and η mesons. different experiments have very different dynamic ranges and radiation hardness requirements, leading to different choices for calorime- ters. the e+e− experiments (cleo, babar, belle) operate at low energies, and the choice has been csi crystals, which are sensitive down to - mev photons. hadron experiments require a large dynamic range and high radiation hardness. the choice has been either high- resolution crystal calorimeters (pbwo ) in btev and cms, or standard sampling calorimeters with more modest energy resolution (lead-scintillators in lhcb, lead-lar in atlas). the hadron calorimeters play a minor role in b-physics. nevertheless, they are used for muon iden- tification and as a muon filter, as well as for hadron triggers and for enhancing k l identification in babar and belle. muons represent the cleanest way of tagging b-meson final states, and all experiments are designed to trigger and reconstruct muons with a high efficiency. some experiments (d , btev, atlas) have a powerful stand-alone muon momentum measurement, provided by toroids in the muon system. . charged hadron identification charged hadron identification is a feature which often puts contradictory requirements on the detector, compromising the operation of other detector elements. therefore dedicated devices such as cherenkov counters are only incorporated in experiments which consider physics with identified hadrons as their first priority. this is obviously the case with dedicated b-physics experiments, which all are relying on cherenkov counters of some sort. in addition, cherenkov counters are used extensively in heavy-ion and astrophysics experiments. general purpose high-energy physics experiments have to compromise between the requirements on the particle identification on one hand, and on the minimisation of material in front of the calorimeters and maximisation of the tracking volume, on the other hand. therefore, most general purpose experiments have chosen to have either a de/dx capability in the tracker (cdf, atlas), or no identification at all – among the recent general purpose collider experiments, only delphi and sld have had cherenkov counters. cherenkov counters are the most practical solution for identifying charged hadrons over a large momentum range, typically between and gev. relativistic particles emit cherenkov radiation in a medium. the angle of emission is proportional to the velocity of particle as θ = arccos( /nβ), where n is the index of refraction. when the angle is measured using photo- sensitive devices, and the momentum is measured independently in another detector, the mass of the particle can be defined. the choice of radiator medium depends on the desired momen- tum range for identification, and on the available space. the larger the refractive index, the larger the emission angle, and the radiator can thus be made thinner. on the other hand, large refractive index is correlated with a high density, which is harmful for the operation of other subdetectors. characteristics of radiators in cherenkov detectors in b-physics experiments are summarised in table . the light collection must be efficient to obtain a sufficient amount of photoelectrons per particle. the detector walls have to have a high transparency for the radiated photon spectrum (walls are typically made of quartz, caf , or borosilicate), while the detectors must have a high quantum efficiency [ ], [ ]. detectors can be either multiwire chambers with gas doped with tmae or tea as the photosensitive component, multiwire chambers with reflective csi photocathode, standard pmts, or hybrid photodiodes (hpds), which combine a photocathode to a small si-strip or si-pad drift chamber [ ]. the specific ionisation (de/dx) can be used at a more limited momentum range than cherenkov radiation for charged hadron identification. the minimum of the bethe-bloch curve for the specific ionisation is around βγ= . - . , and the relativistic rise region of βγ which can be used for particle identification is roughly from to , leading to π/k separation for momenta between and gev [ ]. moreover, the required detector length is larger than for cherenkov counters to achieve the same separation. particle identification by de/dx is thus radiator cf c f aerogel lif fused silica material (quartz) n . . . - . . . (ref. . ) (λ = nm) θmaxc [mrad] pπthr [gev] . . . . . pkthr [gev] . . . . . state gas gas solid solid solid experiment lhcb hera-b belle cleoiii babar btev lhcb lhcb table : characteristics of radiators in rich detectors in b-physics experiments: refractive index n, maximum emission angle θmaxc = arccos( /n), and threshold momenta for pions and kaons (pthr > m/ √ (n − )). the state is given for room temperature. a feasible option for b-physics experiments which have a significant fraction of the b-hadron decay products in this momentum range. this is the case for the e+e− experiments at the Υ( s), and also the central collider experiments, while at forward experiments the momentum spectrum is harder. the particle identification technologies used or foreseen for b-physics experiments are sum- marized in table . experiment hadron identification technique status cdf de/dx in cot ready for runii tof design, pending funding d - cleoiii lif rich, chambers with tea [ , ] being installed babar dirc [ , ] working de/dx in dch working belle aerogel working tof working de/dx in cdc working hera-b c f rich, pmts [ ] working lhcb c f and aerogel rich design cf rich readout with hpds or pmts [ ] btev c f and aerogel rich design atlas de/dx in trt design, pending beamtest verification cms - table : charged hadron identification techniques in different experiments. the hera-b rich detector has proven that a cherenkov counter can be operated success- fully in the harsh forward hadron spectrometer environment [ ]. the rich has been designed to separate pions and kaons in the momentum range between and gev. the radiator used is c f gas. the photons are imaged by two spherical mirrors and two planar mirrors event: apr : : figure : raw hits of a typical event in the hera-b rich [ ]. onto two photon detection systems outside the spectrometer active volume. due to the very high interaction rate and large multiplicity of charged particles, the cherenkov photon flux is up to several mhz per cm , and only photomultipliers were found to operate reliably over the lifetime of the experiment [ ]. the photon detectors thus consist of multianode pmts, with anodes for the inner region and anodes for the outer region to match the expected occupancy. in addition, there is a two-lens telescope in front of each pmt to solve the pmt packing problem and to match the anode dimension to the dispersion error. the detector was completed in january , and the detector was run under realistic data- taking conditions in may . raw hits of a typical event are shown in fig. . the rings could be reconstructed in hadronic events. even without the final tracking, but using a crude momentum estimation by matching the calorimeter clusters with the track angles determined from the rich and assuming that the particles originate from the target, the correlation between the cherenkov ring opening angle and the particle momentum for different particle species could be demonstrated. the babar experiment has constructed a particle identification system based on the detec- tion of internally reflected cherenkov (dirc) light [ ]. the dirc is a novel concept which uses long, thin, rectangular fused silica bars both as radiators and as light guides to direct the produced light via internal reflection to photodetectors. the design has been constrained by the desired momentum range ( mev to gev), and by the demand of minimising material figure : event display of a multi-hadron event the in the babar dirc [ ]. in front of the electromagnetic csi calorimeter. in addition, for high luminosity running condi- tions, the particle identification system must have a fast signal response and be able to tolerate high backgrounds. these boundary conditions are well satisfied by the thin fused silica detector elements ( . mm thick). moreover, the photon detectors can be located outside of the active detector volume. at one end of the detector bars, the cherenkov image is allowed to expand through a standoff region (standoff box) filled with water, which has an index of refraction close to that of fused silica, which minimises the total reflection at the interface of the two materials. the expanded image is then detected in an array of pmts. the instrumented end is located at the backward direction, since in the asymmetric collisions the final state particles emerge mainly to the forward direction. the dummy ends of the detector bars are covered with mirrors to reflect the photons back to the instrumented end. at the time of the conference, five detector elements out of the total were installed in babar [ ]. cosmic ray data showed a large number of photons collected and a close agreement of the data with monte carlo predictions. a typical multihadron event reconstructed in the dirc is shown in fig. . the dominant class of background photons originates from the event itself, while beam-related background can be rejected effectively by the good time-resolution of the pmts. the remainder of the detectors will be installed by end of . the lhcb experiment has the most difficult task for designing their particle identification system due to the largest momentum range to be covered, from to gev. this will be accomplished by using two rich counters, rich with an aerogel and c f radiators, and a rich with a cf radiator [ ]. at lhcb, however, there is a strong correlation between the particle polar angle and momentum, and therefore the angular coverages of the detectors do not have to be the same. the rich is intended for low momentum tracks and will have - mrad polar angle coverage. tilted spherical mirrors will focus the cherenkov rings to photodetectors outside the detector acceptance. the rich is intended for high momentum, and consequently small polar angle tracks, and it will cover polar angles - mrad. the cherenkov photons are reflected with flat mirrors onto spherical mirrors, which will focus the photons to photodetectors. three photodetector options are presently under study: commercial multianode pmts, pad hpds, and pixel hpds. performance comparison of b-physics experiments the performance of several b-physics and general purpose experiments is compared in table . the e+e− b-factory experiments will collect data in clean conditions, but the performance is limited by statistics and the fact that only b d/b + mesons can be produced. presenting the babar estimates as an example, and assuming fb− integrated luminosity, sin β will be measured with an accuracy of . using the b d → j/ψk s decays (charged particle final states) – the precision will be improved to about . combining various other modes. the number of reconstructed, untagged events in the b d → π+π− final state will be only , assuming a branching ratio of . · − . several years of data-taking, and combination of other decay modes will be necessary to obtain reliable information on the angle α. the angle γ could be studied with the decay mode b d → d(∗)π – the statistical accuracy of sin( β + γ) would be . . using decays b± → dk± and b d→ d k∗, fb− would be needed to obtain a precision in the range ◦- ◦. other possible measurements will be measurements on |vub| and |vcb|, as well as rare decays of the type b → kγ. the belle performance should be similar to babar, and if kekb will be successful in achieving the design luminosity of . · cm− s− , the belle experiment should gain about a factor of three in statistics compared to babar. hadronic experiments will be more challenging in view of the much smaller signal-to- background ratio. nevertheless, experience from cdf has already shown the feasibility of achieving significant results in a hadron collider experiment. as we gain more insight on the complicated pattern of cp-violating phenomena, more and more channels will turn out to be important to be experimentally reachable to constrain theoretical uncertainties and to control experimental systematic uncertainties. this leads to the following requirements: • large statistics, • access to b±/b d/b s/bc/Λb hadrons, • trigger on purely hadronic final states, • charged hadron identification. while the hera-b rich is proving the feasibility of charged hadron identification in hadronic experiments, the statistics will be the limiting factor of the hera-b physics pro- gramme. after one year of data-taking, it is foreseen that the sin β will be measured with an measurement babar hera-b cdf lhcb atlas belle (d ) btev cms sin β ** ** ** **** **** δ(sin β) . . . . . sin α * * ** *** ** n(π+π−) rec. unt. unt. unt. tagged tagged angle γ * * *** b d → d(∗)π, b± → dk±, b d → d(∗)π, b± → dk±, b s → d−s k+ b d → dk∗, b d → dk∗ b s → d−s k+ bs mixing * ** **** *** ∆ms reach ps − ps− ps− ps− bs analyses * ** **** *** δ(δγ)) from bs → j/ψφ . . . b → µµ(x) *** *** integrated l fb− fb− fb− fb− fb− table : performance comparison of different experiments. where applicable, **** indicates a % measurement, *** a few% measurement, ** a % measurement and * a measurement. the branching ratio for the decay b d → π+π− was assumed to be . · − [ ]. for the bs → j/ψφ analysis xs = was assumed. accuracy of . using the b d → j/ψk s decays. the number of reconstructed, untagged events in the b d → π+π− final state will be about , assuming a branching ratio of . · − . the expected background, however, cannot be reliably estimated. the b s mixing parameter ∆ms will be reachable up to about ps− [ ]. cdf (and d ) will be serious competitors for the dedicated b-experiments at the first phase of b-experimentation before the lhc startup. cdf at the runii will fulfil all the requirements above, while d will be lacking hadron identification and hadronic trigger. after two years of data-taking ( fb− ), cdf expects to measure sin β with an accuracy of . ( . with a kaon tag using the tof). the number of reconstructed, untagged events in the b d → π+π− final state will be about , assuming a branching ratio of . · − . a . σ π/k separation is expected for particles with transverse momenta greater than gev using the de/dx in the cot, thus helping to extract the signal from the two-body background. cdf has studied possibilities for extracting the angle γ by using decays b± → dk± and b s→ d−s k+, but the preliminary studies indicate a poor accuracy. the decay mode b s → j/ψφ will be experimentally easy, and observing an asymmetry in this decay mode would signal the existence of an anomalous cp violating phase. the parameter δγ can be measured with a precision of . (xs = ). the b s mixing parameter ∆ms will be reachable up to about ps − with the cdf baseline detector ( signal events, signal-to-background ratio of : ). the dedicated b-experiments lhcb at lhc and btev at tevatron are being designed to fulfil all the requirements above in an optimal way. after one year of data-taking ( fb− ), the lhcb experiment will have measured sin β with an accuracy of the order of %. the number of reconstructed and tagged events in the b d → π+π− final state will be about , assuming a branching ratio of . · − . various modes for extracting the angle γ are being investigated – here it will be mandatory to use the full power of the charged hadron identification. the b d→ d k∗ modes will yield a precision of order ◦ for the angle γ. the decay mode b d → d(∗)π will need five years running to get the precision on β + γ down to ◦. the b s→ d−s k+ decay mode will allow measuring γ − δγ with a statistical precision between ◦ and ◦ with one year’s data, depending on the numerical values of the parameters involved. the parameter δγ can be measured with a precision of % in one year using decays b s → j/ψφ and the b s mixing parameter ∆ms will be reachable up to about ps − . rare decays of the type b → k∗ γ can be reconstructed efficiently. compared to the lhcb performance, the btev experiment has actually some advantages despite of the apparent handicap of smaller center-of-mass energy, resulting in quite similar expectations for the physics reach. the longer bunch-spacing and the longer interaction region allow accepting multiple interactions. smaller boost means that the experiment can be made shorter and further away from the beam, saving from radiation damage. if the two-arms and the vertex trigger can be realised this is an obvious big advantage. the general purpose experiments atlas and cms at lhc will be competitive with the dedicated experiments in some channels. in addition, if some charged particle identification can be realised, the spectrum of the b-physics programme can be made much wider. atlas and cms are expected to obtain a very good precision for the measurement of sin β, at the level of % with fb− . various parameters of the b s -meson system will be measured for example with b s → dsπ, dsa , and b s → j/ψφ final states [ ]. the b s mixing parameter ∆ms will be reachable up to about ps− , and the statistical precision for δγ will be about % (xs = ). there are some hopes for the angle α measurement – in atlas, a π/k separation is expected to be possible at the one-standard-deviation level using the trt. the issue is to be verified with beam test data. the number of reconstructed and tagged events in the b d → π+π− final state will be about , assuming a branching ratio of . · − . various other precision measurements such as b-baryon lifetimes and polarizations will be feasible. rare decays of the type b → µµ(x) are particularly suitable for atlas and cms since they are self-triggering, and the high-luminosity data of lhc can be used as well. for example, the decay mode b s → µ + µ−, for which the sm branching fraction is . · − , should be observed. conclusions we are living exciting times. the first direct measurement of an angle of the unitarity triangle has emerged from cdf when the physicists have learned to use the limited statistics in an optimal way. meanwhile, the precision measurements from cleo, lep, sld, cdf and kaon experiments are constraining more and more the unitarity triangle. the first generation of b-physics experiments is getting off the ground and hoping to get to a cruising speed soon, while the tevatron experiments are expected to continue producing even more exciting results in the coming run. from years of planning, designing and reviewing experiments we are now getting into the experimentation itself, and hopefully already in the next beauty conference new results can be reported. it is also important to discuss the future developments. therefore, the future projects at lhc and at tevatron have their due place in this conference. when we learn more about b physics, the experiments can be better optimised to cover fully the physics spectrum, while new ideas, technological progress and experience help us to design better particle detectors. acknowledgements thanks to peter krizan and other local organizers for a well-organized conference in a beautiful location, to peter schlein and samim erhan for making and keeping up the spirit of this conference series, to all the conference participants for an interesting and enjoyable week, and to all the authors of the contributed papers for providing me with the material for this summary. references [ ] m. calvetti, these proceedings. 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[ ] r. j. mountain et al., nucl. instrum. and methods a ( ) . self-locating belief and the sleeping beauty problem adam elga analysis, ( ): - , . in addition to being uncertain about what the world is like, one can also be uncertain about one’s own spatial or temporal location in the world. my aim is to pose a problem arising from the interaction between these two sorts of uncertainty, solve the problem, and draw two lessons from the solution. the sleeping beauty problem: some researchers are going to put you to sleep. during the two days that your sleep will last, they will briefly wake you up either once or twice, depending on the toss of a fair coin (heads: once; tails: twice). after each waking, they will put you to back to sleep with a drug that makes you forget that waking. when you are first awakened, to what degree ought you believe that the outcome of the coin toss is heads? so named by robert stalnaker (who first learned of examples of this kind in unpublished work by arnold zuboff). this problem appears as example of piccione , which motivates two distinct an- swers but suspends judgment as to which answer is correct ( : – ). aumann uses a fair lottery approach to analyse a similar problem. adapted to the sleeping beauty problem, that analysis yields the same answer as the one i will defend in section . however, unlike the argument in aumann , my argument does not depend on betting considerations. the precise effect of the drug is to reset your belief-state to what it was just before you were put to sleep at the beginning of the experiment. if the existence of such a drug seems fanciful, note that it is possible to pose the problem without it — all that matters is that the person put to sleep believes that the setup is as i have described it. first answer: / , of course! initially you were certain that the coin was fair, and so initially your credence in the coin’s landing heads was / . upon being awakened, you receive no new information (you knew all along that you would be awakened). so your credence in the coin’s landing heads ought to remain / . second answer: / , of course! imagine the experiment repeated many times. then in the long run, about / of the wakings would be heads-wakings — wakings that happen on trials in which the coin lands heads. so on any particular waking, you should have credence / that that waking is a heads-waking, and hence have credence / in the coin’s landing heads on that trial. this consideration remains in force in the present circumstance, in which the experiment is performed just once. i will argue that the correct answer is / . suppose that the first waking happens on monday, and that the second waking (if there is one) happens on tuesday. then when you wake up, you’re certain that you’re in one of three ‘predicaments’: h heads and it is monday. t tails and it is monday. t tails and it is tuesday. notice that the difference between your being in t and your being in t is not a differ- ence in which possible world is actual, but rather a difference in your temporal location within the world. (in a more technical treatment we might adopt a framework similar to the one suggested in lewis , according to which the elementary alternatives over which your credence is divided are not possible worlds, but rather centered possible worlds: possible worlds each of which is equipped with a designated individual and time. in such a framework, h , t , and t would be represented by appropriate sets of centered worlds.) let p be the credence function you ought to have upon first awakening. upon first awakening, you are certain of the following: you are in predicament h if and only if the outcome of the coin toss is heads. therefore, calculating p(h ) is sufficient to solve the sleeping beauty problem. i will argue first that p(t ) = p(t ), and then that p(h ) = p(t ). if (upon first awakening) you were to learn that the toss outcome is tails, that would amount to your learning that you are in either t or t . since being in t is subjectively just like being in t , and since exactly the same propositions are true whether you are in t or t , even a highly restricted principle of indifference yields that you ought then to have equal credence in each. but your credence that you are in t , after learning that the toss outcome is tails, ought to be the same as the conditional credence p(t |t or t ), and likewise for t . so p(t |t or t )=p(t |t or t ), and hence p(t )=p(t ). the researchers have the task of using a fair coin to determine whether to awaken you once or twice. they might accomplish their task by either . first tossing the coin and then waking you up either once or twice depending on the outcome; or . first waking you up once, and then tossing the coin to determine whether to wake you up a second time. your credence (upon awakening) in the coin’s landing heads ought to be the same regard- less of whether the researchers use method or . so without loss of generality suppose that they use — and you know that they use — method . now: if (upon awakening) you were to learn that it is monday, that would amount to your learning that you are in either h or t . your credence that you are in h would then be your credence that a fair coin, soon to be tossed, will land heads. it is irrelevant that you will be awakened on the following day if and only if the coin lands tails — in this circumstance, your credence that the coin will land heads ought to be / . but your credence that the coin will land heads (after learning that it is monday) ought to be the same as the conditional credence p(h |h or t ). so p(h |h or t ) = / , and hence p(h )=p(t ). combining results, we have that p(h ) = p(t ) = p(t ). since these credences sum to , p(h )= / . let h be the proposition that the outcome of the coin toss is heads. before being put to sleep, your credence in h was / . i’ve just argued that when you are awakened on monday, that credence ought to change to / . this belief change is unusual. it is not the result of your receiving new information — you were already certain that you would be awakened on monday. (we may even suppose that you knew at the start of the experiment exactly what sensory experiences you would have upon being awakened on monday.) neither is this belief change the result of your suffering any cognitive mishaps during the intervening time — recall that the forgetting drug isn’t administered until well after you are first awakened. so what justifies it? the answer is that you have gone from a situation in which you count your own temporal location as irrelevant to the truth of h, to one in which you count your own temporal location as relevant to the truth of h. suppose, for example, that at the start of the experiment, you weren’t sure whether it was : or : . at that time, you counted to say that an agent receives new information (as i shall use that expression) is to say that the agent receives evidence that rules out possible worlds not already ruled out by her previous evidence. put another way, an agent receives new information when she learns the truth of a proposition expressible by an eternal sentence (quine : ) of some appropriately rich language. to say that an agent counts her temporal location as relevant to the truth of a certain proposition is to say that there is a time t such that the agent’s beliefs are compatible with her being located at t, and her credence in the proposition, conditional on her being located at t, differs from her unconditional credence in the proposition. your temporal location as irrelevant to the truth of h: your credence in h, conditional on its being : , was / , and your credence in h, conditional on its being : , was also / . in contrast (assuming that you update your beliefs rationally), when you are awak- ened on monday, you count your current temporal location as relevant to the truth of h: your credence in h, conditional on its being monday, is / , but your credence in h, con- ditional on its being tuesday, is . on monday, your unconditional credence in h differs from / because it is a weighted average of these two conditional credences — that is, a weighted average of / and . it is no surprise that the manner in which an agent counts her own temporal location as relevant to the truth of some proposition can change over time. what is surprising — and this is the first lesson — is that this sort of change can happen to a perfectly rational agent during a period in which that agent neither receives new information nor suffers a cognitive mishap. at the start of the experiment, you had credence / in h. but you were also certain that upon being awakened on monday you would have credence / in h — even though you were certain that you would receive no new information and suffer no cognitive mishaps during the intervening time. thus the sleeping beauty example provides a new variety of counterexample to bas van fraassen’s ‘reflection principle’ ( : , : ), even an extremely qualified version of which entails the following: any agent who is certain that she will tomorrow have credence x in proposi- tion r (though she will neither receive new information nor suffer any cogni- tive mishaps in the intervening time) ought now to have credence x in r. david lewis once asked ‘what happens to decision theory if we [replace the space of possible worlds by the space of centered possible worlds]?’ and answered ‘not much.’ (lewis : ) a second lesson of the sleeping beauty problem is that something does i am indebted to ned hall for pointing out that an answer of / conflicts with the reflection principle. happen. namely: at least one new question arises about how a rational agent ought to update her beliefs over time. massachusetts institute of technology cambridge, ma - , usa adam@mit.edu references aumann, r. j., s. hart and m. perry. . the forgetful passenger. games and economic behavior : – . lewis, d. . attitudes de dicto and de se. in his philosophical papers, volume i, – . new york: oxford university press. piccione, m. and a. rubenstein. . on the interpretation of decision problems with imperfect recall. games and economic behavior : – . quine, w. v. . word and object. cambridge, mass.: the mit press. van fraassen, b. c. . belief and the will. journal of philosophy : – . van fraassen, b. c. . belief and the problem of ulysses and the sirens. philosophical studies : – . many thanks to jamie dreier, gary gates, ned hall, vann mcgee, robert stalnaker, roger white, sarah wright, the participants in a conference at brown university (at which an earlier version of this paper was presented), and an anonymous referee. j. fash. bus. vol. , no. : - , sep. issn - (print) http://dx.doi.org/ . /jfb. . . . issn - (online) corresponding author: barng keejung, tel. + - - - , fax. + - - - e-mail: @nate.com this research was presented at the spring conference of the korean society of fashion business. 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 방 기 정 대전대학교 뷰티건강관리학과 the research compared the general high school and beauty specialized high school student's interests of beauty and beauty products, and beauty behavior barng keejung dept. of beauty health management, daejeon university abstract in this study, changes in the timing of puberty physicality and mentality and beauty characteristics of high school students were characterized for high school students and the general high school population in order to distinguish between interest and beauty and beauty products and beauty behavior for comparative analysis. first, for beauty characteristics of high school students and the general high school population, differences in beauty action and beauty characteristics of high school students were higher than this beauty behavior. secondly, for the high school students and high school beauty characteristics of general high school population for beauty and beauty products, the difference between interest and multi-functional beauty products that characterize high school students has beauty and beauty products with multi-functional beauty products interest being high. third, high school students and high school beauty characterize the general high school population of beauty is different from behaviors on its factors with common factors including the psychological gratification 'for reasons of appearance management looks for reasons that do not' have time to manage the response. two groups of factors that characterize the differences in appearance and beauty as areason to manage high school students interested in the 'style' order, high school students do not manage 패 션 비 즈 니 스 제 권 호 서론i. 아름다움에 대한 관심은 누구나 소유하고 있으며 , 자신의 외모를 아름답게 가꾸기 위해 여성들은 적극 적으로 외모 관리를 하고 있다 특히 청소년은 외. , 모나 이성에 대한 호기심이 많아지고 신체적 정신, , 적 변화를 겪게 되는 시기로 그로인한 외모와 신체 에 대한 사회적인 인식의 영향력이 매우 커지고 있 다(jung, kim, & lee, ). 외모관리는 자신에 대한 시각적 이미지를 만들어나갈 뿐만 아니라 상황 에 맞추어 외모상징의 의미를 전달함으로써 자신을 표현하는 수단이라고 할 수 있다. 우리나라에서 뷰 티라는 단어는 미용을 대신하여 사용되어지고 있으 며 미용의 사전적 의미는 얼굴이나 머리를 아름답, ‘ 게 매만지는 것 으로 정의되어 있다 외모에 대한 ’ . 관심도가 높아지는 청소년 시기의 여고생들은 자기 스스로 만족스러운 외모를 가꾸기 위해 화장이나 장 신구 등으로 치장을 하고 타인이나 이성에게 좋은 이미지로 평가 받고 싶어 한다 외모지상주의가 확. 대되면서 좋은 신체적 외모가 행복과 성공을 위한 중요한 조건이나 요인으로 작용하면서 뷰티산업과 뷰티행동은 청소년에게 외모 지향적 심리와 모방 성 향이 강하게 반영이 되고 있다 뷰티산업은 화장품. , 다이어트 네일아트 미용문신 피부미용관리 등을 , , , 통해 신체를 미학적으로 꾸미는 것을 목적으로 하는 산업을 말하며 뷰티산업의 범위는 외과적 수술을 , 통하지 않고 몸을 미학적으로 바꾸어 내는 것이라 볼 수 있다 이는 인공적인 과정을 통해 자연 미인. ‘ ’ 을 만드는 과정 전체를 의미하며 우리 생활 전반에 걸쳐 중요한 자리를 하고 있다 뷰티(barng, ). 행동은 인류의 역사와 더불어 시작되었으며 현대에, 는 대중매체의 발달과 생활수준의 향상으로 뷰티산 업은 뷰티행동이 대중에게 보편화되는 계기를 마련 하였다 뷰티행동은 사춘기 여고생들의 집단 간 의. 사소통을 위한 도구의 형태로 나타나고 있으며 사, 회문화적 변화를 통해 여고생들은 중요한 소비주체, 잠재적 소비자로 떠오르고 있으며 구매 연령도 중, 저가 화장품의 보급과 대중매체의 영향으로 점점 대 상자의 연령이 낮아지며 확대되고 있으며 스마트폰 , 세대인 고등학생을 겨냥한 타깃 마케팅이 성행하고 있다 고등학교 여학생들은 사춘기의 영향으로 급속. 한 신체발달과 신체적 변화로 인해 외모에 관심을 갖게 되고 이성과 타인에게 관심을 받고 싶은 욕구, 가 급증하게 되면서 다양한 외모관리행동을 하게 된 다 또한 그들은 대중매체의 영향으로 유행에 민감. 한 세대가 되며 새로운 유행의 선두주자가 되기도 한다 여성들의 사회진출 증가로 인한 여성의 사회. 적 지위 역할 기능이 다양화 되면서 패션과 뷰티에 , 대한 관심이 증가하고 있으며 좋은 신체적 외모가 , 행복과 성공을 위한 중요한 조건으로 인식되고 있 다 의 연구에서는 요즘 이슈. park and park( ) 로 부각되고 있는 몸짱 얼짱 이라는 용어를 통해' ', ' ' 서 외모 가꾸기와 외모지상주의 시대의 여성들은 자 신의 이미지 변화를 위해 패션과 뷰티 소비생활에 깊이 관여하고 있다고 하였다 외모가 개인의 자아. 존중감 인간관계 행동양식 등에 매우 중요한 영향, , 을 미치기 때문이다 는 의복 외모 및 . m. lee( ) , 신체에 대한 만족 불만족은 자아존중감 사회성이, , 나 사회참여도와 관련이 되며 전반적인 생활만족도, reasons for lack of interest in the 'general' as a response. beauty characteristics of high school students in the beauty, beauty products, and products demonstrated a multi-functional information gathering with lots of attention, and much ability can have an active beauty behavior. the general high school population lacks the ability to gather information in accordance with interested beauty behavior being passive. the two groups and beauty behavior patterns of consumption could see that a difference occurred. key words : 뷰티행동 미용특성화 beauty behavior( ), beauty specialized high-school students( 고등학생 뷰티제품 뷰티제품 관심), beauty products( ), beauty products interest( ), 멀티기능 뷰티제품multi-functional beauty products( ) 방기정 / 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 에도 영향을 줄 수 있다 자기만족은 옷차림과 머리. 모양 메이크업 성형 체중관리 등의 외모관리에 영, , , 향을 미칠 수 있고 더 나아가서는 사회생활과 자신 의 삶을 질적으로 향상시키는데 기여한다고 할 수 있다 선행연구에는. (barng, ; jun, ; h. lee & o, ; y. lee, ; seol & choi, 의 외모 및 화장 헤어스타일 ; yang, ) , , 피부 관리에 관한 연구 등이 있었으나 같은 고등학 교 학생이라고 하더라도 미용특성화 고등학교와 같 은 유행선도 또는 외모관심 집단에 대한 뷰티 및 제 품 및 뷰티행동에 대한 비교연구는 부족하였다 그. 러나 같은 고등학생이지만 미용특성화 고등학생들은 뷰티정보 수집능력도 많고 뷰티 관심도와 그에 따, 른 적극적인 뷰티행동이 있을 수 있고 일반 고등학, 생들은 뷰티정보 수집능력도 부족하고 뷰티관심도에 따른 뷰티행동이 소극적이며 이 두 그룹의 소비 및 , 뷰티행동 패턴은 다를 것이다 따라서 본 연구에서. 는 미용특성화 고등학생과 일반 고등학생으로 구별 하여 미용특성화 고등학교와 같은 유행선도 또는 외 모관심 집단과 멀티기능 뷰티제품 및 뷰티행동을 비 교 분석하고 두 집단의 뷰티패턴의 분석과 사용자 , 요구 중심의 뷰티 및 멀티기능 뷰티제품과 뷰티행동 에 대한 비교분석을 하고자 한다 첫째 미용특성화 . , 고등학생의 뷰티관심 뷰티제품 및 멀티기능 뷰티제, 품과 뷰티행동에 어떤 차이가 있는지 알아보고 둘 째 뷰티관심과 멀티기능 뷰티제품이 뷰티행동에 미, 치는 영향에 관하여 두 집단의 뷰티 소비행동에 미 치는 영향에 관해 알아보고자 한다. 이론적 배경. Ⅱ 청소년기의 특성 . 현대사회가 급속히 변화되고 산업이 발달하여 물 질적으로는 풍요로워 졌으나 현대인은 정서적으로 불안과 스트레스 속에서 살아가고 있으며 그 수는 , 날로 늘어나고 있다 특히 청소년의 경우 심리적. , 사회적으로 갑작스런 변화를 경험하는 시기이기 때 문에 과도한 긴장과 불안 자신과의 갈등 미 타인과, 의 대인관계 문제 등으로 많은 갈등을 경험한다 청. 소년기는 아동기와는 달리 자신 속에 여러 다양한 자아들이 내재하고 있음을 인식한다 또한 다양한 . 그룹으로부터 다양한 역할을 요구 받는다 이 단계. 에서 내가 나 되는데 실패하게 되면 정체성이나 역 할의 혼란이 오게 된다 이러한 혼란은 영웅이나 탤. 런트에게 자신을 지나치게 동일화시킴으로 야기되기 도 한다 현시대의 소비 형태는 물질주(choi, ). 의와 루키즘으로 인한 가치관의 혼란 속에서 타인들 의 시선을 끌 목적으로 패션 메이크업 헤어 피부 , , , 관리 체중조절 성형수술 등 외적인 것에 대한 과, , 시소비가 증가하고 있는 것으로 나타나고 있다 패. 션과 뷰티관련 서비스 및 제품은 옷차림이나 장신 구 신체외모 등의 외적인 것들로 착용자의 사회적 , 위치와 신분을 알려주는 지표로 활용되고 있으며, 또한 대인관계에서 자기표현의 수단으로 사회생활의 상호작용에서 매우 중요한 영향을 미친다 특히 이. 성에 대한 관심과 패션과 뷰티관련 서비스 및 제품 은 개성이 있고 호감이 가는 외모를 가꾸는 수단으 로서 많이 활용되고 있다(barng, ). 뷰티관심 및 뷰티행동 . 우리는 일상생활에서 다른 사람들에게 다양한 외 모관리행동을 보인다 외모관리를 하면서 자신의 이. 미지를 만들어 나가고 그 이미지를 내면화 시켜 나 가는 것이다 미 에는 내적인 면과 외적인 면이 . ( )美 있는데 내적인 면에 비해 외적인 면은 다른 사람들, 에게 보여 지기 때문에 다른 사람과 자신을 비교하 게 되고 대부분의 사람들은 자신의 외모에 많은 관, 심을 갖고 외모가 더 나아지도록 노력함으로써 외모 는 자기 자신이 만들어 내는 것이라 할 수 있다 (seol & choi, ) 외모를 가꾸기 위한 개인의 . 의지는 메이크업 헤어스타일 또한 현대 사회에 만, , 연하고 있는 성형중독이나 다이어트와 같은 몸매관 리는 자신의 외모를 변화시키며 사회의 미적 기준과 그에 부합하는 이상적인 이미지를 실현하기 위해 뷰 티 관리행동에 관여한다고 볼 수 있다. 뷰티관심은 사회적 이상형과 자신의 실제 외모와의 차이를 좁히 기 위해 메이크업 피부 관리 헤어 연출 성형수술, , , , 패 션 비 즈 니 스 제 권 호 체중관리 등의 수단을 활용하여 외모를 관리하는 행 동과 관심의 정도 의미한다 신체관리를 비롯하여 . 여러 가지 도구 즉 화장품 외모 관련 제품 등을 , , 사용하여 관리하는 정도 의미한다 외모란 우리가 . 타인을 지각할 때 단서로 사용하는 신체적 특성으로 체격 얼굴 모습 의복 화장 안경과 같은 건강상, , , , , 태 체취 등을 포함하며 외모관리 , (m. lee, ), 행동이란 다른 사람에게 자신의 모습을 나타내 보일 때 자신이 기대하는 대로 보이도록하기 위하여 여러 도구 즉 의복 화장품 액세서리 소품 등을 사용하, , , , 는 것을 의미한다(seol & choi, ). 매일 아침 의복을 선택하고 화장하는 행동을 포함한 외모를 가 꾸는 행동은 다른 사람들이 우리를 어떻게 지각하는 가에 많은 영향을 받는다 그러므로 외모관리는 자. 신에 대한 시간적 이미지를 만들어나갈 뿐만 아니라 상황에 맞추어 외모상징의 의미를 전달함으로써 자 신을 표현하는 수단이라고 할 수 있다(h. lee & o, ). 외모는 자신에 대한 외관적 정보를 타인에게 직접적으로 전달하는 결정적인 요인으로 외적인 아 름다움에 의해 다른 특성까지 긍정적으로 지각되는 후광효과를 지니기도 한다. m. lee and lee( ) 는 외모 관심도란 외모 향상을 위해 의복과 화장, 장신구 등과 같은 신체 장식에 대해 지속적으로 흥 미를 가지는 정도라고 규정하였다. 이러한 견해에 따라 본 연구에서는 뷰티 관심을 뷰티제품 구매의 제반 상황에서 뷰티제품을 대상으로 개인이 지각하 는 중요성과 관심으로 정의한다. 뷰티제품은 사람의 ‘ 외모를 손질하여 아름답게 꾸미는 물건 제품 이라, ’ 고 설명할 수 있다 자신의 모습을 더(barng, ). 욱 세련되고 매력적인 개성적인 이미지로 나타낼 , 수 있는 자기표현의 수단으로 복잡하고 다양화되는 사회에서 자신을 나타내기 위한 수단 및 도구 성별 및 연령이 다양하고 대상자의 연령 또한 낮아지고 , 있다 우리는 매일 아침 의복을 선택하고 화장하는 . 행동을 포함한 외모를 가꾸는 행동을 통해 다른 사 람들이 우리를 어떻게 지각하는가에 많은 영향을 받 는다 고도의 경제성장과 가치관의 변화는 의복뿐만 . 아니라 뷰티와 관련된 소비행동에 있어서도 많은 의 식의 변화를 가져왔다 특히 토탈 코디네이션의 개. 념은 패션의 영역을 의복에서부터 뷰티에 이르기까 지 확대시켜 중요하게 인식되고 있다 이러한 관리. 행동은 개인의 신체적 정신적 노력으로 이루어지며 , 이를 통해 사람들은 자신에 대한 만족감을 획득할 수 있을 것이다 대부분의 사람들은 자신의 외모에 . 지대한 관심을 가지며 자신들의 외모를 향상시키기 , 위해 노력한다. 뷰티 . 제품의 특성 화장품은 사람의 몸을 청결하게 하고 아름답게 하 며 더욱 매력적으로 변화시켜 주기 위하여 사용하, 는 물품 또는 피부와 모발을 건강하게 유지하기 위, 해 신체에 바르거나 뿌리거나 그 밖에 이와 유사한 방법으로 사용하는 물품으로 인체에 대한 작용이 적 은 것을 말한다 뷰티는 머리 얼굴 손(ha, ). , , , 손톱 등을 가꾸는 의미로 사용하며, 우리나라에서 ‘뷰티 라는 단어는 미용 대신하여 사용한다’ ‘ ’ . 뷰티제 품은 사람의 외모를 손질하여 아름답게 꾸미는 물건 및 제품을 뜻한다 우리나라의 화장품법에서 정하고 . 있는 법적인 의미의 기능성 화장품에는 미백 주름, , 자외선 및 탠닝 과 관련된 제품으로 한정되(tanning) 어 있으며 법적 의미의 기능성 화장품이다 그러나 . 본 연구에서의 기능이라 함은 여러 가지 물리적 화, 학적 기술의 기능을 포함한 다양한 기능을 동시에 지닌 제품을 의미하며 멀티기능 제품은 여러 가지의 기능을 가지고 있는 다기능의 뷰티제품을 의미한다. 미용 특성화 고등학교 . 특성화 고등학교는 소질과 적성 및 능력이 유사한 학생을 대상으로 특정분야에 인재양성을 목적으로 하는 교육 또는 자연현장 실습 등 체험 위주의 교, 육을 전문적으로 실시하는 고등학교이다 학생 자신. 의 적성과 능력을 고려하여 조기에 진로를 결정하, 여 전문가로 양성될 수 있도록 다양한 전문 분야의 교육을 실시하는 고등학교로 여기에서 고등학교 유 형은 일반고 특목고 특성화고 자율고 개의 유형, , , 으로 미용분야는 특성화 고등학교에 속하며 기존 , 전문계 미용 고등학교에서 명칭이 미용특성화 고등 학교로 변경되었다 미용 전문분야에 집중교육 및 . 방기정 / 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 관련 분야의 상급학교 진학 준비하는 학교로 특정 미용분야에 소질 적성 흥미 관심을 가지고 집중적, , , 으로 교육을 받고자 하는 보통학생 대상의 고등학교 이다(elementary, secondary education act enforcement decree article , ). 연구 방법iii. 연구문제 . 미용특성화 고등학생과 일반 고등학생의 뷰티 ) 행동에는 차이가 있을 것이다. 미용특성화 고등학생과 일반 고등학생의 뷰티 ) 및 뷰티제품 멀티기능 뷰티제품 관심의 차이가 있, 을 것이다. 미용특성화 고등학생과 일반 고등학생의 뷰티 ) 행동에 미치는 요인에는 차이가 있을 것이다. 연구대상 및 자료수집 . 연구방법은 문헌연구와 설문조사를 통한 실증연구 로 진행하였으며 설문조사의 분석단위는 개인이며 , 서울 및 경기 충남 대전지역의 미용특성화 고등학, 생 명과 일반 고등학생 명을 중심으로 뷰티 관심과 뷰티행동에 대한 비교분석 연구를 위한 연구 대상으로 비확률 표본추출 방법인 편의추출을 실시 하였다 본 연구의 자료 수집은 년 월 일부. 터 월 일까지 이루어졌다 설문지 배부는 연구자 . 가 담임선생님을 대상으로 설문조사에 대해 간단히 설명한 후 설문지를 배포하였고 작성된 설문지는, table . measuring tools configuration number measured variables number of questions how to measure part i demographic characteristics multiple choice / technology type part ii interest in beauty multiple choice / steps how to likert part iii beauty product step likert method part iv beauty behavior step likert method 응답한 후 즉시 회수하였다 자료수집 방법은 기존. 의 선행연구를 참고하여 본 연구의 목적에 맞게 연 구자가 고안한 설문지를 이용한 자가 기입식 설문조 사를 통해 수집하여 총 부가 본 연구의 통계분, 석을 위하여 사용되었다. 측정도구 . 본 연구에서 사용된 조사도구는 설문지를 사용하 였으며 측정도구의 구성은 아래 , table 과 같다. 총 부로 구성되었다 부는 인구 통계적 특성에 관 . 한 문항으로 만들어졌으며 부는 뷰티관심 관련된 , 문항으로 부는 뷰티제품 관련된 문항으로 부는 , , 뷰티행동 관련 문항으로 작성하여 조사하였다 구성. 내용은 인구 통계적 특성 문항 외모관리행동( ), ( 문항 뷰티관심도 문항 뷰티제품 관심도 문), ( ), ( 항 멀티기능 뷰티제품 관심도 문항 뷰티행동), ( ), ( 문항 의 개의 영역으로 구성하였다 뷰티 및 뷰티) . 제품 관심도 멀티기능 뷰티제품 관심도 뷰티행동 , , 개 영역의 각 문항은 전혀 그렇지 않다 점 에서 ‘ ’( ) 매우 그렇다 점 의 점 척도로 구성되었으‘ ’( ) likert 며, 점수가 높을수록 각 문항의 내용이 더 그러하다 는 것을 뜻하였다. 인구 통계적 특성 ) 인구 통계적 변인은 학년별 거주지별 한 달 용 , , 돈별 이성 친구의 유무를 조사하였다 일반적으로 , . 여고생의 학년별 한 달 용돈과 이성친구의 유무는, 뷰티행동과 뷰티제품과 관계가 있으며 뷰티제품과 , 멀티기능 뷰티제품에 대한 관여 등에 영향을 줄 수 있을 것으로 판단되어 선정하게 되었다. 패 션 비 즈 니 스 제 권 호 뷰티 관심도 및 외모관리 행동 ) 뷰티 관심도와 외모관리 행동은 패션 및 뷰티업계 와 사회전반에서 머리와 얼굴 손 발톱 등을 아름, , 답게 단장하는 것을 의미하고 이러한 행위 등에 마, 음을 두고 주의를 기울이고 가꾸는 것과 이러한 뷰 티산업 전반에 대한 관심도를 의미한다 뷰티관심도. 를 측정하기 위하여 사용된 문항은 선행연구(jeong & kim, ; hwang, joe, & yoo, ; oh, 의 내용을 토대로 연구자가 kim, lee, & jin, ) 본 연구의 대상자에 맞게 수정 보완하였으며 최종 , , 문항으로 구성되었다 이 문항에 대하여 신뢰도 . 검사결과 문항의 신뢰도는 였다 측정방법은 . . 점 형 척도를 사용하였으며 점수가 높을수록 likert , 뷰티관심이 더 많은 것을 의미하였다. 뷰티제품 및 멀티기능 뷰티제품 관심도 ) 뷰티제품은 사람의 외모를 손질하여 아름답게 꾸 미는 물건 및 제품을 뜻하며 멀티기능 제품은 여러 , 가지의 기능을 가지고 있는 다기능의 뷰티제품을 의 미한다 본 연구의 연구대상인 고등학교 학생을 고. 려하여 인구통계학적 범위를 학년별 용돈별 이성, , , 친구 유무별로 분류하였다 뷰티제품 및 멀티기능 . 제품의 관심을 측정하기 위해 사용된 문항은 선행연 구(barng, ; kim, ; h. lee & o, ; 의 내용을 참고로 하여 연구자가 수정 yang, ) 보완하였으며 뷰티제품 문항 멀티기능 제품 문, , 항으로 구성되었다 뷰티제품 관심 문항에 대하여 . 신뢰도 검사결과는 멀티기능제품 관심에 대한 . , table . the reliability of the measurement tool division number of questions alpha interest in beauty . the interest of beauty products . beauty behavior . the interest of multi-function beauty products . 문항의 신뢰도는 이였다 측정방법은 점 . . likert 형 척도를 사용하였으며 점수가 높을수록 뷰티제품 , 및 멀티기능 제품에 대한 관심이 더 많은 것을 뜻하 였다. 뷰티 행동 ) 뷰티행동은 자신의 모습을 더욱 세련되고 매력적 인 이미지 개성적인 이미지로 나타낼 수 있는 자기 , 표현의 수단이며 도구이다 뷰티행동의 측정도구는 . 외모관리 중 뷰티행동에 관한 문항으로 이루어졌다. 뷰티행동과 관련된 선행연구(ahan & cho, ; 그리고 외모관리에 대한 선행seol & choi, ), 연구 를 기초(han, ; song, kim, & na, ) 로 하여 전문가 집단과 토의하여 연구목적에 맞게 수정 보완하여 작성하였다 뷰티행동을 측정하기 , . 위해 사용된 문항은 의 선행연seol and choi( ) 구에서 본 연구 대상자에 부합하는 문항을 선택하 였다 이 문항에 대하여 신뢰도 검사결과 문항의 . 신뢰도는 였다. . 독립변수인 뷰티행동은 . 종속변수인 신뢰도, 는 뷰티 관심도 뷰티제품의 관심도 멀 . , . , 티기능 제품의 관심도 로 모두 이상으로 . , . 신뢰도를 나타냈다 에서 보는 바와 같이 . table 가 모두 이상으로 나타났다 따라cronbach . . α 서 본 연구의 측정도구는 신뢰할만한 수준임을 알 수 있다 측정방법은 점 형 척도를 사용하였. likert 으며 점수가 높을수록 뷰티행동이 더 높다는 것을 , 의미하였다 본 연구 측정도구의 신뢰도를 검증한 . 결과는 아래 와 같다table . 방기정 / 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 분석방법 . 본 연구의 수집된 자료는 spss(statistical 프로그package for the social science) win . 램을 이용하여 분석하였다 분석 기법으로는 연구 . 대상자의 일반적 특성을 파악하기 위해 빈도와 백분 율을 산출하였으며 일반 고등학교 여학생과 미용특, 성화 고등학교 여학생의 뷰티관심과 뷰티제품의 관 심도 뷰티행동 그리고 멀티기능 제품의 관심을 알, , 아보기 위해 χ 검증과 검증 그(chi-square) t-test( ), 리고 일원변량분석 을 실시하였one-way anova( ) 다. 결과 및 논의. Ⅳ 연구대상 . 본 연구의 연구 대상자의 일반적 특성은 table 과 같다 연령별로는 일반 고등학교 여학생은 세. 가 로 가장 높은 분포를 보인 반면에 미용특 . % 성화 고등학교 여학생은 세가 로 가장 많았 . % 다 거주지별로는 일반 고등학교 여학생은 서울이 . 로 대부분을 차지한 반면에 미용특성화 고등 . % 학교 여학생은 충청도가 로 대부분을 차지하 . % 였다 한 달 용돈별로는 일반 고등학교 여학생은 . 만원 미만이 로 가장 많은 반면에 미용특 . %～ 성화 고등학교 여학생은 만원 이상 이 로 . % 가장 많았다 이성친구 유무별로는 일반 고등학교 . 학생 미용특성화 고등학교 여학생 로 . %, . % 단순한 친구가 가장 많았으나 일반 고등학교 학생, 이 로 미용특성화 고등학교 여학생 보 . % . % 다 높은 분포를 보였고 미용특성화 고등학교 여학, 생은 로 일반 고등학교 여학생 보다 이 . % . % 성친구가 많았다 또한 외모를 관리하는 이유로는 . 일반 고등학교 여학생 미용특성화 고등학교 . %, 여학생 로 심리적 만족감이 가장 큰 이유로 . % 나타났으며 미용특성화 고등학교 여학생은 , . % 로 일반 고등학교 여학생 보다 스타일에 관심 . % 이 더 많았다 외모를 관리하지 않는 이유로는 일반 . 고등학교 여학생은 시간이 없어서와 관심이 없어서, 가 각각 로 가장 높은 분포를 보인 반면에 미 . % 용특성화 고등학교 여학생은 시간이 없어서 에 ‘ ’ 로 가장 많은 응답을 하였다 . % . 이러한 연구결과는 미용특성화 고등학생이 한 달 용돈별 이성 친구 유무별 스타일 관심이 높게 나, , 타나 목적과 관심에 따른 고등학생의 뷰티 패턴을 보여주었다 이러한 연구결과는 의 연구 . jun( ) 결과를 뒷받침한다 또한 공통점으로는 외모를 관리. 하는 이유로 심리적 만족감을 이야기 하고 있는데, 이는 seol and choi( ), bae and sung( ) 에서 밝힌 집단별 화장추구는 자신감 기능성 아름, , 다움 추구 등 화장을 통한 여러 가지 혜택추구를 한 다는 연구결과와 대중매체의 영향으로 유행에 민감 한 청소년의 뷰티행동에 영향을 주는 요소라고 할 수 있다. 외모관리 유무에 대한 시간이 없어서 라는 이러 ‘ ’ 한 연구결과는 일반 고등학교 및 미용특성화 고등학 교 여학생은 다기능 멀티기능을 통한 빠르고 간편하 며 사용하기 쉬운 제품을 원한다는 것을 유추할 수 , 있는 결과였다 이는 미용특성화 고등학생 유행선도 . 집단이 편의성 보다는 이상적 신체이미지 추구와 개 성을 표현할 수 있는 사회적 적합성을 선택하고 외, 모관심 집단은 매력적인 신체 표현과 편의성을 중요 하게 고려한다는 의 연구결과bae and sung( ) 를 지지 한다 뷰티와 뷰티제품 관심도 . 뷰티 관심도 ) 일반 고등학교 여학생과 미용특성화 고등학교 여 학생의 뷰티에 대한 관심도에 대해 살펴본 결과는 와 같다table . 나는 외모 미용에 관심이 많다 ’(t=- . , p<. ) 와 무료 미용에 대한 강좌가 있으면 듣고 싶‘ 다 나는 유행하는 화장기법을 ’(t=- . , p<. ), ‘ 안다 에 대해서는 미용고등학교 ’(t=- . , p<. ) 여학생이 일반 고등학교 여학생보다 높은 인식을 보 였으며 통계적으로도 유의미한 차이를 보였다 다, . ‘ 패 션 비 즈 니 스 제 권 호 division general high school beauty high school age less than years old ( . ) ( . ) years old ( . ) ( . ) years old ( . ) ( . ) more than years ( . ) ( . ) living seoul ( . ) ( . ) gyeong-gi ( . ) ( . ) chung-cheong - ( . ) monthly allowance less than , won ( . ) ( . ) less than , to , won ( . ) ( . ) less than , to , won ( . ) ( . ) less than , to , won ( . ) ( . ) more than , won ( . ) ( . ) etc. ( . ) ( . ) male friends yes ( . ) ( . ) simply be friends ( . ) ( . ) no ( . ) ( . ) why appearance management psychological satisfaction (confidence) ( . ) ( . ) beneficial to the relationship between friends ( . ) ( . ) to show strong ( . ) - did not want to fall behind the fashion ( . ) ( . ) reason to give favor to a friend ( . ) ( . ) many time - ( . ) many are interested in the original style ( . ) ( . ) etc. ( . ) ( . ) why does not the administration looks more importantly, it is first (studies, etc.) ( . ) ( . ) appearance is not important ( . ) ( . ) lack of time ( . ) ( . ) economic difficulties ( . ) ( . ) lack of interest ( . ) ( . ) i think students should not have to ( . ) ( . ) etc. ( . ) ( . ) total ( . ) ( . ) table . general characteristics of study subjects 방기정 / 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 table . interest in beauty division general high school (n= ) beauty high school (n= ) totality (n= ) t p m sd m sd m sd i am much interested in cosmetic appearance . . . . . . - . *** . beauty courses for free if you want to hear is . . . . . . - . *** . i know trendy makeup techniques . . . . . . - . *** . i know the brand of the various kinds of cosmetics . . . . . . . . i want to buy a product color . . . . . . - . * . i want to take up professional . . . . . . - . *** . i am interested in many different kinds of beauty products . . . . . . - . ** . cosmetics shops that i go to this it is interesting to take a look . . . . . . - . *** . interest in beauty . . . . . . - . *** . * p<. , ** p<. , *** p<. 양한 화장품 종류의 브랜드를 안다 에 대해서는 일’ 반 고등학교 여학생이 미용고등학교 여학생보다 높 은 인식을 보였으나 유의미한 차이는 아니었다 사. ‘ 고 싶은 색조제품이 있다 와 전문’(t=- . , p<. ) ‘ 가에게 메이크업을 받아보고 싶다’(t=- . , 여러 가지 뷰티제품에 관심이 많p<. ), ‘ 다 화장품 샾에 가면 이것저것 둘’(t=- . , p<. ) ‘ 러보는 것이 재미있다 에 대해서’(t=- . , p<. ) 는 미용고등학교 여학생이 일반 고등학교 여학생보 다 높은 인식을 보였으며 계열에 따라 유의미한 차, 이를 보였다 전체적으로 뷰티관심도 는 미용고등학. ‘ ’ 교 여학생이 일반 고등학교 여학생보다 높았으며, 통계적으로도 유의미한 차이를 보였다(t=- . , p<. ). 이상에서 일반 고등학교 여학생과 미용특성화 고 등학교 여학생의 뷰티에 대한 관심도에 대해 살펴본 결과 미용특성화 고등학교 여학생이 일반 고등학교 , 여학생보다 뷰티에 대한 관심도가 높음을 알 수 있 다 이러한 결과는 . oh and kim( ), h. lee and 의 연구 결과와도 일치하는데 이는 정보탐o( ) , 색에 있어서 인터넷 스마트폰 등 다양한 디지털 매, 체를 통한 뷰티관련 정보의 잦은 노출과 높은 관심 을 통해 미용특성화 고등학생들은 일반 고등학교 학 생들 보다 뷰티에 대한 관심이 높다는 연구결과를 지지한다. 뷰티제품의 관심도 ) 일반 고등학교 여학생과 미용특성화 고등학교 여 학생의 뷰티 제품에 대한 관심도에 대해 살펴본 결 과는 와 같다 나는 인터넷이나 케이블 를 table . ‘ tv 통해 뷰티제품 관련 정보를 얻는다’(t=- . , 패 션 비 즈 니 스 제 권 호 와 시간이 많이 걸려도 뷰티제품에 대한 새p<. ) ‘ , 로운 아이디어를 찾는 것을 즐긴다’(t=- . , 에 대해서는 미용특성화 고등학교 여학생이 p<. ) 일반 고등학교 여학생보다 높은 인식을 보였으며 계, 열에 따라 유의미한 차이를 보였다 나는 주로 주변 . ‘ 사람이 사용하는 뷰티제품을 구입하는 편이다 와 뷰’ ‘ 티제품 종류가 너무 많아 선택하기 어렵다 현재 나’, ‘ 는 나에게 맞는 뷰티제품을 사용해오고 있다 하나’, ‘ 의 제품으로 다양한 효과를 얻을 수 있는 뷰티제품을 좋아 한다 에 대해서는 미용특성화 고등학교 여학생’ 이 일반 고등학교 여학생보다 높은 인식을 보였으나 division general high school (n= ) beauty high school (n= ) totality (n= ) t p m sd m sd m sd i'm over the internet or cable tv to get information about beauty products . . . . . . - . ** . i have even if it takes a lot of time, looking for new ideas for beauty products that enjoy . . . . . . - . *** . i mostly used by people around to buy a piece of beauty products . . . . . . - . . if there are too many kinds of beauty products, it is difficult to choose . . . . . . - . . i have been using and beauty products are suitable for . . . . . . - . . one product i can get a variety of effects like beauty products . . . . . . - . . i look to spend most of the extra money to decorate . . . . . . - . *** . i have another popular beauty products than those who know a lot about . . . . . . - . ** . i would like to purchase the newly released beauty products often come . . . . . . - . *** . the interest of beauty products . . . . . . - . *** . table . the interest of beauty products ** p<. , *** p<. 유의미한 차이는 아니었다 나는 외모를 가꾸기 위해 . ‘ 용돈의 대부분을 지출하는 편이다’(t=- . , p<. ) 와 나는 다른 사람들보다 유행하는 뷰티제품에 대해 ‘ 많이 알고 있다 새로 나온 뷰티제’(t=- . , p<. ), ‘ 품 구입을 좋아하고 자주 하는 편이다’(t=- . , 에 대해서는 미용특성화 고등학교 여학생이 p<. ) 일반 고등학교 여학생보다 높은 인식을 보였으며 통, 계적으로도 유의미한 차이를 보였다 전체적으로 뷰. ‘ 티제품의 관심도 는 미용특성화 고등학교 여학생이 일’ 반 고등학교 여학생보다 높았으며 계열에 따라 유의, 미한 차이를 보였다(t=- . , p<. ). 방기정 / 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 이상에서 일반 고등학교 여학생과 미용특성화 고 등학교 여학생의 뷰티제품에 대한 관심도에 대해 살 펴본 결과 미용특성화 고등학교 여학생이 일반 고, 등학교 여학생보다 뷰티제품에 대한 관심도가 높음 을 알 수 있다 의 연구결과를 통해 일. yang( ) 반 고등학교 여학생의 경우 외모에는 관심이 많으나 아직 화장법이 미숙하여 자신에게 어울리는 화장 방 법을 모르거나 화장품 사용에 대한 지식이 부족하여 화장품 사용이 다양하지 않기 때문인 것으로 사료된 다 이와 같은 결과는 미용특성화 고등학교 학생들. 은 유행을 선도하는 유행선도 집단 또는 외모관심을 table . the interest of multi-function beauty products division general high school (n= ) beauty high school (n= ) totality (n= ) t p m sd m sd m sd i had heard about the various features of beauty products . . . . . . - . ** . i had purchase the multi-function beauty products . . . . . . - . *** . i can be a simple product than many features . . . . . . . . i have a cute and funny can a drastic beauty products . . . . . . - . ** . i can travel or disposable multi-functional beauty products . . . . . . - . * . i used the pop star multi function wants to buy beauty products . . . . . . - . *** . i'm great to be used as disposable once, always use the uncomfortable . . . . . . - . ** . multi-function beauty products are fun, convenient and efficient . . . . . . - . *** . i have always been interested in beauty products, first of all i would like to try out the new multi-function beauty products. . . . . . . - . *** . the interest of multi-function beauty products . . . . . . - . *** . * p<. , ** p<. , *** p<. 가지고 있는 집단으로 생각할 수 있으며 이는 선행, 연구 의 유행선도 및 외모관심bae and sung( ) 집단은 다양한 정보원을 활용하여 뷰티제품의 관심 이 높으며 구입비용 또한 높다는 연구결과를 지지, 한다. 멀티기능 뷰티제품의 관심도 ) 일반 고등학교 여학생과 미용특성화 고등학교 여 학생의 멀티기능 뷰티제품에 대한 관심도에 대해 살 펴본 결과는 과 같다table . 패 션 비 즈 니 스 제 권 호 여러 가지 기능이 있는 뷰티 제품에 대해서 들어 ‘ 봤다 와 나는 멀티기능 뷰티제품을 ’(t=- . , p<. ) ‘ 구입한 적이 있다 에 대해서는 미’(t=- . , p<. ) 용특성화 고등학교 여학생이 일반 고등학교 여학생 보다 높은 인식을 보였으며 통계적으로도 유의미한 , 차이를 보였다 나는 여러 가지 기능이 있는 것보. ‘ 다는 단순한 제품이 좋다 에 대해서는 일반 고등학’ 교 여학생이 미용특성화 고등학교 여학생보다 높은 인식을 보였으나 유의미한 차이는 아니었다. 나는 귀엽고 재미있는 과감한 뷰티 제품이 좋 ‘ 다 와 나는 여행용이나 일회용 멀’(t=- . , p<. ) ‘ 티기능 뷰티제품이 좋다 대중스’(t=- . , p<. ), ‘ 타가 사용하는 멀티기능 뷰티제품을 구입하고 싶 다 일회용으로 사용하기에는 좋’(t=- . , p<. ), ‘ 지만 사용이 불편하다 멀티기능 , ’(t=- . , p<. ), ‘ 뷰티 제품은 재미있고 편리하고 효율적이라고 생각 , 한다 나는 매사에 관이 많으며 ’(t=- . , p<. ), ‘ 남보다 먼저 새로운 멀티기능 뷰티 제품을 시도해 보고자 한다 에 대해서는 미용특’ (t=- . , p<. ) 성화 고등학교 여학생이 일반 고등학교 여학생보다 높은 인식을 보였으며 계열에 따라 유의미한 차이, 를 보였다 전체적으로 멀티기능 뷰티제품 관심도. ‘ ’ 는 미용특성화 고등학교 여학생이 일반 고등학교 여 학생보다 높았으며 통계적으로도 유의미한 차이를 , 보였다(t=- . , p<. ). 이상에서 일반 고등학교 여학생과 미용특성화 고 등학교 여학생의 멀티기능 뷰티제품에 대한 관심도 에 대해 살펴본 결과 미용특성화 고등학교 여학생, 이 일반 고등학교 여학생보다 멀티기능 뷰티제품에 대한 관심도가 높음을 알 수 있다 미용특성화 고등. 학교 학생들은 최신 유행하는 화장법과 뷰티 제품 에 대한 관심과 정보를 많이 가지고 있는 집단으로 멀티기능 뷰티제품의 관심이 높은 것으로 나타났다. 은 유행을 선도하는 집단에서bae and sung( ) 는 다양한 화장품을 사용하고 높은 관심으로 유행화 장을 습득하고 많은 종류의 화장품을 사용한다고 하 였다 외모와 유행에 관심이 적은 집단일수록 적은 . 화장품을 사용한다는 연구결과는 기초제품 위주의 화장품을 사용하고 색조제품의 사용이 적은 것을 말 하고 있다 하지만 외모관리 유무에 대한 두 집단. , 의 공통적인 연구결과에서 시간이 없어서 라는 연‘ ’ 구 결과는 두 집단의 여학생들은 다기능 멀티기능을 통한 빠르고 간편하며 사용하기 쉬운 제품을 원한, 다는 것을 유추할 수 있는 결과라고 할 수 있다. 뷰티 행동 . 일반 고등학교 여학생과 미용특성화 고등학교 여 학생의 뷰티 행동에 대해 살펴본 결과는 과 table 같다 색조 화장을 해 본 적이 있다. ‘ ’(t=- . , 와 컬러로션 크림 파우더 등을 사용해 p<. ) ‘ bb , 본 적이 있다 틴트 립 글로즈’(t=- . , p<. ), ‘ , , 립스틱 등을 사용해 본 적이 있다’(t=- . , p<. ), 아이섀도나 아이라이너를 사용해 본 적이 있‘ 다 눈썹집게나 마스카라를 사용’(t=- . , p<. ), ‘ 해 본 적이 있다 색조 제품을 ’(t=- . , p<. ), ‘ 바르고 외출한 적이 있다 색조 ’(t=- . , p<. ), ‘ 제품 사용을 자주 하는 편이다 에 ’(t=- . , p<. ) 대해서는 미용특성화 고등학교 여학생이 일반 고등 학교 여학생보다 높은 인식을 보였으며 계열에 따, 라 유의미한 차이를 보였다 학교에 색조 제품을 . ‘ 하고 간 적이 있다 에 대해서는 미용특성화 고등학’ 교 여학생이 일반 고등학교 여학생보다 높은 인식을 보였으나 유의미한 차이는 아니었다. 나는 뷰티제품 구입을 좋아하는 편이다 에 대해 ‘ ’ 서는 미용특성화 고등학교 여학생이 일반 고등학교 여학생보다 높은 인식을 보였으며 통계적으로도 , 유의미한 차이를 보였다 전체적(t=- . , p<. ). 으로 뷰티 행동 은 미용특성화 고등학교 여학생이 ‘ ’ 일반 고등학교 여학생보다 높았으며 계열에 따라 , 유의미한 차이를 보였다(t=- . , p<. ). 이상에서 일반 고등학교 여학생과 미용특성화 고 등학교 여학생의 뷰티행동에 대해 살펴본 결과 미, 용특성화 고등학교 여학생이 일반 고등학교 여학생 보다 뷰티행동이 높음을 알 수 있다 이러한 결과. 를 통해서 뷰티에 관심과 뷰티제품에 관심이 많은 고등학교 학생은 유행을 선도하고 외모관심이 많은 집단이라고 할 수 있는 미용특성화 고등학생은 매 우 적극적인 뷰티행동을 한다는 것을 알 수 있었다. 방기정 / 일반고와 미용특성화고 학생의 뷰티 및 제품 관심도와 뷰티행동 비교 연구 table . beauty behavior division general high school (n= ) beauty high school (n= ) totality (n= ) t p m sd m sd m sd i tried the color makeup . . . . . . - . *** . i have a base color lotion, bb cream, powder, etc., had used . . . . . . - . *** . i tint, lip-geulrojeu, had used lipstick. . . . . . . - . ** . i used to use eye shadow or eyeliner. . . . . . . - . *** . i used to use eyelash-curler and mascara . . . . . . - . *** . i have never go out rubbing the tint products . . . . . . - . *** . i use the tint products often come . . . . . . - . *** . i tint products makeup and had gone to school. . . . . . . - . . i like to buy beauty products. . . . . . . - . *** . beauty behavior . . . . . . - . *** . ** p<. , *** p<. 결론v. 본 연구는 신체적으로 정신적으로 변화시기인 사 춘기의 여고생 중에서 미용특성화 고등학생과 일반 고등학생으로 구별하여 뷰티 및 뷰티제품 관심과 뷰 티행동을 비교분석 하고자 하였으며 연구결과는 다, 음과 같다. 첫째 미용특성화 고등학교 여학생과 일반 고등학 , 교 여학생의 뷰티패턴에는 차이가 있었으며 그에 , 따른 뷰티행동에도 적극성과 정보의 노출에 따른 차 이가 있었다 또한 미용특성화 고등학교 여학생은 . 매우 다양한 많은 종류의 색조제품을 이용하고 활용 하는 뷰티행동이 높다는 것을 알았다 둘째 미용특. , 성화 고등학교 여학생과 일반 고등학교 여학생의 뷰 티 및 뷰티제품 멀티기능 뷰티제품 관심은 차이가 , 있었으며 유행을 선도하고 외모에 관심이 높은 집, 단으로서 미용특성화 고등학교 여학생이 뷰티 및 뷰 티제품 멀티기능 뷰티제품 관심도가 높았다 셋째, . , 미용특성화 고등학생과 일반 고등학생의 뷰티행동에 미치는 요인에는 차이가 있었으며 공통적인 요인으, 로는 외모관리를 하는 이유로 심리적 만족감이 크다‘ ’ 라는 연구결과를 통해 자신감 기능성 아름다움 추, , 구 등 여러 가지 혜택추구를 한다고 볼 수 있다 또. 한 외모관리를 하지 않는 이유로 시간이 없어서 로 ‘ ’ 응답을 하였다 이와 같은 결과를 통해 유행에 민. , 감하고 뷰티제품에 관심이 많은 일반 고등학교 및 , 미용특성화 고등학교 여학생은 다기능 멀티기능을 통한 빠르고 간편하며 사용하기 쉬운 제품을 원한, 다는 것을 유추할 수 있는 결과였다 이상에서 볼 . 패 션 비 즈 니 스 제 권 호 때 고등학교 여학생들은 같은 고등학생이지만 미용, 특성화 고등학교 여학생들은 일반 고등학교 학생보 다 뷰티 및 뷰티제품 멀티기능 뷰티제품에 관심이 , 많고 뷰티정보 수집력 또한 많아 뷰티 관심과 그에 따른 매우 적극적인 뷰티행동이 있을 수 있었다 또. 한 다기능 멀티기능을 통한 빠르고 간편하며 사용, 하기 쉬운 제품을 원한다는 것을 유추할 수 있는 결 과였다 일반 고등학생들은 뷰티정보 수집능력도 부. 족하고 뷰티관심에 따른 뷰티행동이 소극적으로 이 , 두 그룹의 소비 및 뷰티행동 패턴은 차이가 있었음 을 알 수 있었다 본 연구 결과를 통해 청소년의 외. 모관리 행동에 대한 뷰티행동과 유형 파악을 통해 학문적 기초 자료를 제공하고 관련업계 마케팅 전략 수립에 방향을 제공하는데 본 연구의 의의가 있다, 고 하겠다 그러나 본 연구의 대상자가 지역적 한계. 로 객관화하기에는 무리가 있으며 추후 후속연구를 , 위한 제언으로 뷰티제품에서도 유형별 세분화와 상, 표충성도 브랜드 인지도 등 다양한 변수들과의 연, 구가 진행되어야 할 것이다. references ahan, h., & cho, k. 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( ). a study for recognition to the relativity on skin health of cosmetics in a girl’s high school students. the journal of korea beauty design society, ( ), - . received(july , ) revised(august , ) accepted(september , ) manuscript number facial attractiveness: beauty and the machine yael eisenthal school of computer science tel-aviv university tel-aviv , israel yre @columbia.edu gideon dror senior lecturer department of computer science academic college of tel-aviv-yaffo tel-aviv , israel tel: - - fax: - - gideon@mta.ac.il eytan ruppin professor of computer science and medicine school of computer science tel-aviv university tel-aviv , israel tel: - - fax: - - ruppin@post.tau.ac.il corresponding author: gideon dror gideon@mta.ac.il none of this material has been published or is under consideration for publication elsewhere. abstract this work presents a novel study of the notion of “facial attractiveness” in a machine-learning context. to this end, we collected human beauty ratings for datasets of facial images and used various techniques for learning the attractiveness of a face. the trained predictor achieves a significant correlation of . with the average human ratings. the results clearly show that facial beauty is a universal concept, which can be learned by a machine. analysis of the accuracy of the beauty prediction machine as a function of the size of the training data indicates that a machine producing human-like attractiveness rating could be obtained given a moderately larger dataset. introduction in this work, we explore the notion of facial attractiveness through the application of machine learning techniques. we construct a machine which learns from facial images and their respective attractiveness ratings to produce human- like evaluation of facial attractiveness. our work is based on the underlying theory that there are objective regularities in facial attractiveness to be analyzed and learned. in the introduction, we first briefly describe the psychophysics of facial attractiveness and its evolutionary origins. we then provide a review of previous work done in the computational analysis of beauty, attesting the novelty of our work. . the psychophysics of beauty . . beauty and the beholder the subject of visual processing of human faces has received attention from philosophers and scientists, such as aristotle and darwin, for centuries. within this framework, the study of human facial attractiveness has had a significant part - “beauty is a universal part of human experience, it provokes pleasure, rivets attention, and impels actions that help ensure survival of our genes” (etcoff, ). various experiments have empirically shown the influence of physical attractiveness on our lives, both as individuals and as part of a society; its impact is obvious by the amounts of money spent on plastic surgery and cosmetics each year. yet, the face of beauty, something we can recognize in an instant, is still difficult to formulate. this outstanding question regarding the constituents of beauty has led to a large body of ongoing research by scientists in the biological, cognitive and computational sciences. over centuries, the common notion in this research has been that beauty is "in the eye of the beholder", that individual attraction is not predictable beyond our knowledge of a person's particular culture, historical era or personal history. however, more recent work suggests that the constituents of beauty are neither arbitrary nor culture bound. several rating studies by perrett et al. and other researchers have demonstrated high cross-cultural agreement in attractiveness rating of faces of different ethnicities (cunningham, roberts, wu, barbee & druen, ; jones, ; perrett, may & yoshikawa, ; perrett, lee, penton- voak, rowland, yoshikawa, burt, henzi, castles & akamatsu, ). this high congruence over ethnicity, social class, age and sex has led to the belief that perception of facial attractiveness is data-driven, i.e. that the properties of a particular set of facial features are the same irrespective of the perceiver. if different people can agree on which faces are attractive and which are not, when judging faces of varying ethnic background, then this suggests that people everywhere are using similar criteria in their judgements. this belief is further strengthened by the consistent relations, demonstrated in experimental studies, between attractiveness and various facial features, with both male and female raters. cunningham et al. showed a strong correlation between beauty and specific features, which were categorized as neonate (features such as small nose and high forehead), mature (e.g. prominent cheekbones) and expressive (e.g. arched eyebrows). they concluded that beauty is not an inexplicable quality which lies only in the eye of the beholder (cunningham, ; cunningham, barbee & pike, ). a second line of evidence in favor of a biological rather than an arbitrary cultural basis of physical attractiveness judgements comes from studies of infant preferences for face types. langlois et al. showed pairs of female faces (that had been previously rated for attractiveness by adults) to infants only a few months old (langlois, roggman, casey, ritter, rieser-danner & jenkins, ). the infants preferred to look at the more attractive face of the pair, indicating that even at two months of age, adult-like preferences are demonstrated. slater et al. demonstrated the same preference in newborns (slater, von der schulenberg, brown, badenoch, butterworth, parsons et al., ). the babies looked longer at the attractive faces, regardless of the gender, race, or age of the face. the "owner vs observer” hypothesis was further studied in various experiments. zaidel explored the question of whether beauty is in the perceptual space of the observer or a stable characteristic of the face (chen, german & zaidel, ). results showed that facial attractiveness is more dependent on physiognomy of the face than on a perceptual process in the observer - both for male and female observers. . . evolutionary origins since darwin, biologists have studied natural beauty's meaning in terms of the evolved signal content of striking phenotypic features. evolutionary scientists claim that the perception of facial features may be governed by circuits shaped by natural selection in the human brain. aesthetic judgements of faces are not capricious but, instead, reflect evolutionary functional assessments and valuations of potential mates (thornhill & gangestad, ). these “darwinian” approaches are based on the premise that attractive faces are a biological "ornament" that signals valuable information; attractive faces advertise a "health certificate", indicating a person's "value" as a mate (thornhill & gangestad, ). advantageous biological characteristics are probably revealed in certain facial traits, which are unconsciously interpreted as attractive in the observer’s brain. facial attributes like good skin quality, bone structure and symmetry, for example, are associated with good health and, therefore, contribute to attractiveness. thus, human beauty standards reflect our evolutionary distant and recent past and emphasize the role of health assessment in mate choice, or, as phrased by anthropologist donald symons, “beauty may be in the adaptations of the beholder". research has concentrated on a number of characteristics of faces, which may honestly advertise health and viability. langlois and others have demonstrated a preference for average faces: composite faces, a result of digital blending and averaging of faces, were shown to be more attractive than most of the faces used to create them (grammer & thornhill, ; langlois & roggman, ; langlois, roggman & musselman, ; o´toole, price, vetter, bartlett & blanz, ). evolutionary biology holds that in any given population, extreme characteristics tend to fall away in favor of average ones, therefore, the ability to form an average-mate template would have conveyed a singular survival advantage (symons, ; thornhill & gangestad, ). the averageness hypothesis, however, has been widely debated. average composite faces tend to have smooth skin and be symmetric; these factors, rather than averageness per se, may lead to the high attractiveness attributed to average faces (alley & cunningham, ). both skin texture (fink, grammer & thornhill, ) and facial bilateral symmetry (grammer & thornhill, ; mealey, bridgstock & townsend, ; perrett, burt, penton-voak, lee, rowland & edwards, ) have been shown to have a positive affect on facial attractiveness ratings. the averageness hypothesis has also received only mixed empirical support. later studies found that, although averageness is certainly attractive, it can be improved upon. composites of beautiful people were rated more appealing than those made from the larger, random population (perrett et al., ). also, exaggeration of the ways in which the prettiest female composite differed from the average female composite resulted in a more attractive face (o’toole, deffenbacher, valentin, mckee, huff & abdi, ; perrett et al., , ); these turned out to be sexually dimorphic traits, such as small chin, full lips, high cheekbones, narrow nose and a generally small face. these sex- typical, estrogen dependent characteristics in females may indicate youth and fertility, and are, thus, considered attractive (perrett et al., ; symons, , ; thornhill & gangestad, ). . computational beauty analysis the previous section clearly indicates the existence of an objective basis underlying the notion of facial attractiveness. yet the relative contribution to facial attractiveness of the aforementioned characteristics and their interactions with other facial beauty determinants are still unknown. different studies have examined the relationship between subjective judgements of faces and their objective regularity. morphing software has been used to create average and symmetrized faces (langlois & roggman, ; perrett et al., , ), as well as attractive and unattractive prototypes (http://www.beautycheck.de), in order to analyze their characteristics. other approaches have addressed the question within the study of the relation between aesthetics and complexity, which is based on the notion that simplicity lies at the heart of all scientific theories (“occam's razor” principle). schmidhuber created an attractive female face composed from a fractal geometry based on rotated squares and powers of two (schmidhuber, ). exploring the question from a different approach, johnston produced an attractive female face using a genetic algorithm, which evolves a “most beautiful” face according to interactive user selections (johnston & franklin, ). this algorithm mimics, in an oversimplified manner, the way humans (consciously or unconsciously) select for features they find the most attractive. measuring the features of the resulting face showed it to have “feminized” features. this study and others, which have shown attractiveness and femininity to be nearly equivalent for female faces (o’toole et al., ), have been the basis for a commercial project, which uses these sex-dependent features to determine the sex of an image and predict its attractiveness (http://www.intelligent-earth.com). . this work previous computational studies of human facial attractiveness have mainly involved averaging and morphing of digital images and geometric modeling to construct attractive faces. in general, computer techniques used include delineation, transformation, prototyping and other image processing techniques, most requiring fiducial points on the face. in this work, rather than attempt to morph or construct an attractive face, we explore the notion of facial attractiveness through the application of machine learning techniques. using only the images themselves, we try to learn and analyze the mapping from two- dimensional facial images to their attractiveness scores, as determined by human raters. the cross-cultural consistency in attractiveness ratings demonstrated in many previous studies has led to the common notion that there is an objective basis to be analyzed and learned. the remainder of this paper is organized as follows: section presents the data used in our analyses – both images and ratings, where section describes the representations we chose to work with. section describes our experiments with learning facial attractiveness, presenting prediction results and analyses. finally, section consists of a discussion of the work presented and general conclusions. additional details are provided in appendix a. the data . image datasets to reduce the effects of age, gender, skin color, facial expression and other irrelevant factors, subject choice was confined to young caucasian females in frontal view with neutral expression, without accessories or obscuring items (e.g. jewelry). furthermore, to get a good representation of the notion of beauty, the dataset was also required to encompass both extremes of facial beauty: very attractive as well as very unattractive faces. we obtained two datasets, which met the above criteria, both of relatively small size of images each: . dataset # contains young caucasian (american) females in frontal view with neutral expressions, face and hair comprising the entirety of the picture. the images all have identical lighting conditions and nearly identical orientation, in excellent resolution, with no obscuring or distracting features, such as jewelry and glasses. the pictures were originally taken by japanese photographer akira gomi. images were received with attractiveness ratings. . dataset # contains caucasian (israeli) females, aged approximately , in frontal view, face and hair comprising the entirety of the picture. most of the images have neutral expressions, but, in order to keep the dataset reasonably large, smiling images in which the mouth was relatively closed were also used. the images all have identical lighting conditions and nearly identical orientation. this dataset required some image preprocessing and is of slightly lower quality. the images contain some distracting features, such as jewelry. the distributions of the raw images in the two datasets were found to be too different for combining the sets, and, therefore, all our experiments were conducted on each dataset separately. dataset # , which contains high-quality pictures of females in the preferred age range, with no distracting or obscuring items, was the main dataset used. dataset # , which is of slightly lower quality, containing images of younger women with some distracting features (jewelry, smiles), was used for exploring cross-cultural consistency in attractiveness judgement and in its main determinants. both datasets were converted to grayscale to lower the dimension of the data and to simplify the computational task. . image ratings . . rating collection dataset # was received with ratings, but, to check consistency of ratings across cultures we collected new ratings for both datasets. to facilitate both the rating procedure and the collection of the ratings, we created an interactive html- based application, which was used by all our raters. this provided a simple rating procedure, in which all participants received the same instructions and used the same rating process. the raters were asked to first scan through the entire dataset (in grayscale), to obtain a general notion of the relative attractiveness of the images, and only then to proceed to the actual rating stage. they were instructed to use the entire attractiveness scale, and to consider only facial attractiveness in their evaluation. in the rating stage, the images were shown in random order to eliminate order effects, each on a separate page. a rater could look at a picture for as long as he or she liked and then score it. the raters were free to return to pictures they had already seen and adjust their ratings. images in dataset # were rated by observers - male, female, most in their twenties. for dataset # , ratings were collected from male and female raters of similar age. each facial image was rated on a discrete integer scale between (very unattractive) and (very attractive). the final attractiveness rating of a facial image was the mean of its ratings across all raters. . . rating analysis in order to verify the adequacy and consistency of the collected ratings, we examined the following properties: • consistency of ratings: the raters were randomly divided into two groups. we calculated the mean ratings of each group and checked consistency between the two mean ratings. this procedure was repeated numerous times and consistently showed a correlation of . - . between the average ratings of the two groups for dataset # and a correlation of . - . for dataset # . the mean ratings of the groups were also very similar, for both datasets, and a t-test confirmed that the rating means for the two groups were not statistically different. • clustering of raters: the theory underlying the project is that individuals rate facial attractiveness according to similar, universal standards. therefore, our assumption was that all ratings are from the same distribution. indeed, clustering of raters produced no apparent grouping. specifically, a chi-square test that compared the distribution of ratings of male versus female raters showed that there are no statistically significant differences between these two groups. in addition, the correlation between the average female ratings and average male ratings was very high: . for dataset # and . for dataset # . the means of the female and male ratings were also very similar, and a t-test confirmed that the means of the two groups were not statistically different. the results show no effect of observer gender. an analysis of the original ratings for dataset # (collected from austrian raters) vs. the new ratings (collected from israeli raters) shows a high similarity in the images rated as most and least attractive. a correlation of . was found between the two sets of ratings. these findings strongly reinforce previous reports of high cross-cultural agreement in attractiveness rating. face representation numerous studies in various face image processing tasks (e.g. face recognition and detection) have experimented with various ways to “specify” the physical information in human faces. the different approaches tried have demonstrated the importance of a broad range of shape and image intensity facial cues (bruce & langton, ; burton, bruce & dench, ; valentine & bruce, ). the most frequently encountered distinction regarding the information in faces is a qualitative one between feature-based and configurational-based information, i.e. discrete, local, featural information vs. spatial interrelationship of facial features. studies suggest that humans perceive faces holistically and not as individual facial features (baenninger, ; haig, ; young, hellawell & hay, ), yet experiments with both representations have demonstrated the importance of features in discriminative tasks (bruce & young, ; moghaddam & pentland, ). this is a particularly reasonable assumption for beauty judgement tasks, given the correlation found between features and attractiveness ratings. our work uses both kinds of representations. in the configurational representation, a face is represented with the raw grayscale pixel values, in which all relevant factors, such as texture, shading, pigmentation and shape, are implicitly coded (though difficult to extract). a face is represented by a vector of pixel values created by concatenating the rows or columns of its image. the pixel-based representation of a face will be referred to as its "pixel image". the featural representation is motivated by arguments tying beauty to ideal proportions of facial features such as distance between eyes, width of lips, size of eyes, distance between the lower lip and the chin etc. this representation is based on the manual measurement of facial feature distances and ratios that reflect the geometry of the face (e.g. distance between eyes, mouth length and width). the facial feature points, according to which these distances were defined, are displayed in figure . the full list of feature measurements is given in appendix a, along with their calculation method. all raw distance measurements, which are in units of pixels, were normalized by the distance between pupils, which serves as a robust and accurate length scale. to these purely geometric features we added several non-geometric ones: average hair color, an indicator of facial symmetry and an estimate of skin smoothness. the feature-based measurement representation of a face will be referred to as its "feature vector". the pixel-based representation of a face will be referred to as its "pixel image". figure : feature landmarks used for feature-based representation learning attractiveness we turn to present our experiments with learning facial attractiveness, using the facial images and their respective human ratings. the learners were trained with the pixel representation and with the feature representation, separately. . dimension reduction the pixel images are of an extremely high dimension, of the order of , (equal to image resolution). given the high dimensionality and redundancy of the visual data, the pixel images underwent dimension reduction with principal component analysis (pca). pca has been shown to relate reliably to human performance on various face image processing tasks, such as face recognition (o’toole, abdi, deffenbacher & valentin, , turk & pentland, ) and race and sex classification (o’toole, deffenbacher, abdi & bartlett, ), and to be semantically relevant: the eigenvectors pertaining to large eigenvalues have been shown to code general information, such as orientation and categorical assessment, which has high variance and is common to all faces in the set (o’toole et al., ; o´toole, vetter, troje & bülthoff, ; valentin & abdi, ). those corresponding to the smaller eigenvalues code smaller, more individual variation (hancock, burton & bruce, ; o’toole et al., ). pca was also performed on the feature-based measurements, in order to decorrelate the variables in this representation. this is important since strong correlations, stemming, for example, from left-right symmetry, were observed in the data. . . image alignment for pca to extract meaningful information from the pixel images, the images need to be aligned, typically by rotating, scaling and translating, to bring the eyes to the same location in all the images. to produce sharper eigenfaces, we aligned the images according to a second point as well – the vertical location of the center of the mouth, a technique known to work well for facial expression recognition (padgett & cottrell, ). this non-rigid transformation, however, involved changing face height to width ratio. to take this change into account, the vertical scaling factor of each face was added to its low-dimensional representation. as the input data in our case is face images and the eigenvectors are of the same dimension as the input, the eigenvectors are interpretable as faces and are often referred to as “eigenfaces” (turk & pentland, ). the improvement in sharpness of the eigenfaces from the main dataset as a result of the alignment can be seen in figure . each eigenface deviates from uniform gray where there is variation in the face set. the left column consists of two eigenfaces extracted from pca on unaligned images; face contour and features are blurry. the middle column shows eigenfaces from images aligned only according to eyes. the eyes are indeed more sharply defined, but other features are still blurred. the right column shows eigenfaces from pca on images aligned both by eyes and vertical location of mouth – all salient features are much more sharply defined. figure : left column: eigenfaces from unaligned images, middle: eigenfaces from images aligned only by eyes, right: eigenfaces from images aligned both by eyes and mouth . . eigenfaces pca was performed on the input vectors from both representations, separately. examples of eigenvectors extracted from the pixel images from the main dataset can be seen in figure . the eigenfaces in the top row are those pertaining to the highest eigenvalues, the middle row shows eigenfaces corresponding to intermediate eigenvalues and the bottom row presents those pertaining to the smallest eigenvalues. as expected, the eigenfaces in the top row seem to code more global information, such as hair and face shape, while the eigenvectors in the bottom row code much more fine, detailed feature information. each eigenface is obviously not interpretable as a simple single feature (as is often the case with a smaller dataset), yet it is clearly seen in the top-row eigenfaces that the directions of highest variance are hair and face contour. this is not surprising as the most prominent differences between the images are in hair color and shape, which also causes large differences in face shape (due to partial occlusion by hair). smaller variance can also be seen in other features, mainly eyebrows and eyes. figure : eigenfaces from largest to smallest eigenvalues (top to bottom) . feature selection the eigenfaces are the features representing the face set; they can be combined in a certain weighting to represent a specific face. a low-dimensional representation using only the first eigenvectors minimizes the squared-error between the face representation and the original image, and is sufficient for accurate face recognition (turk & pentland, ). however, omitting the dimensions pertaining to the smaller eigenvalues decreases the perceptual quality of the face (o’toole et al., , ). consequently, we anticipated that using the first m eigenfaces would not produce accurate results in our attractiveness evaluation task. indeed, these experiments resulted in poor facial attractiveness predictions. we therefore selected the eigenfaces most important to our task by sorting them according to their relevance to attractiveness ratings. this relevance was estimated by calculating the correlation of the eigenvector projections with the human ratings across the various images. interestingly, in the pixel representation, the features found most correlated with the attractiveness ratings were those pertaining to intermediate and smaller eigenvalues. figure shows the eigenfaces, where the top row displays those pertaining to the highest eigenvalues and the bottom row presents the eigenfaces with projections most correlated with human ratings. while the former show mostly general features of hair and face contour, the latter also clearly show the lips, the nose tip and eye size and shape to be important features. the same method was used for feature selection in the feature-based representation. the feature measurements were sorted according to their correlation with the attractiveness ratings. it should be noted that, despite its success, using correlation as a relevance measure is problematic, as it assumes the relation between the feature and the ratings to be monotonic. yet, experiments with other ranking criteria that do not make this assumption, such as chi-square and mutual information, produced somewhat inferior results. figure : eigenfaces pertaining to highest eigenvalues (top row) and highest correlations with ratings (bottom row) . attractiveness prediction the original data vectors were projected onto the top m eigenvectors from the feature selection stage (where m is a parameter on which we performed optimization) to produce a low-dimensional representation of the data as input to the learners in the prediction stage. . . classification into two attractiveness classes although the ultimate goal of this work was to produce and analyze a facial beauty predictor using regression methods, we begin with a simpler task, on which there is even higher consistency between raters. to this end, we recast the problem of predicting facial attractiveness into a classification problem - discerning "attractive" faces (the class comprised of highest % rated images) from "unattractive" faces (the class of lowest % rated images). the main classifiers used were standard k-nearest neighbors (knn) (mitchell, ) and support vector machines (svm) (vapnik, ). the best results obtained are shown in table , which displays the percentage of correctly classified images. classification using the knn classifier was good; correct classifications of %- % of the images were achieved. classification rates with svm were slightly poorer, though, for the most part, in the same percentage range. both classifiers performed better with the feature vectors than with the pixel images; this is particularly true for svm. best svm results were achieved using a linear kernel. in general, classification (particularly with knn) was good for both datasets and ratings, with success percentages slightly lower for the main dataset. knn does not use specific features, but rather averages over all dimensions, and, therefore, does not give any insight into which features are important for attractiveness rating. in order to learn what the important features are, we used a c . decision tree (quinlan, , ) for classification using feature vectors without preprocessing by pca. in most cases, the results did not surpass those of the knn classifier, but the decision tree did give some insight into which features are “important” for classification. the features found most informative were those pertaining to size of the lower part of the face (jaw length, chin length), smoothness of skin, lip fullness and eye size. these findings are all consistent with previous psychophysics studies. dataset # dataset # knn % % pixel images svm % % knn % % feature vectors svm % % table : percentage of correctly classified images . . the learners for the regression task following the success of the classification task, we proceeded to the regression task of rating prediction. the predictors used for predicting facial beauty itself were, again, knn and svm. for this task, however, both predictors were used in their regression version, mapping each facial image to a real number that represents its beauty. we also used linear regression, which served as a baseline for the other methods. targets used were the average human ratings of each image. the output of the knn predictor for a test image was computed as the weighted average of the targets of the image's k nearest neighbors, where the weight of a neighbor is the inverse of its euclidean distance from the test image. that is, let v ,…,vk be the set of k nearest neighbors of test image v with targets y ,…yk, and let d ,…,dk be their respective euclidean distances from v. the predicted beauty y for the test image v is then ki w yw y i i i ii k , , == ∑ ∑ where wi = ( σ+id ) - is the weight of neighbor vi and where σ is a smoothing parameter. on all subsequent uses of knn we set σ = . knn was run with k values ranging from to . as a predictor for our task, knn suffers from a couple of drawbacks. first, it performs averaging, and, therefore, its predicted ratings had very low variance, and all extremely high or low ratings were evened out and often not reached. in addition, it uses a euclidean distance metric, which need not reflect the true metric for evaluation of face similarity. therefore, we also studied an svm regressor as an attractiveness predictor, a learner which does not use a simple distance metric and does not perform averaging in its prediction. the svm method, in its regression version, was used with several kernels: linear, polynomials of degree and and gaussian with different values of γ, where log γ∈{- , - , - , }. γ is related to the width parameter σ by γ = /( σ ). we performed a grid search over the values of slack parameter c and the width of regression tube w such that log c∈{- , - , - , , } and w∈{ . , . , . , . }. in all runs we used a soft-margin svm implemented in svmlight (joachims, ). due to the relatively small sample sizes, we evaluated the performance of the predictors using cross validation; predictions were made using leave-n-out, with n= for knn and linear regression and n= for svm. . . results of facial attractiveness prediction predicted ratings were evaluated according to their correlation with the human ratings, using the pearson correlation. the best results of the attractiveness predictors on the main dataset are shown in figure . the left figure shows the best correlations achieved with the pixel-based representation, and the right figure shows the best results for the feature-based representation. prediction results for the pixel images show a peak near m= features, where the maximum correlation achieved with knn is approximately . . feature-based representation shows a maximum value of nearly . at m= features, where the highest correlation is achieved both with svm and linear regression. highest svm results in both representations were reached with a linear kernel. results obtained on the second dataset were very similar. the normalized mse of the best predicted ratings is . - . (vs. a normalized mse of of the "trivial predictor", which constantly predicts the mean rating). knn performance was poor, significantly worse than that of the other regressors in the feature-based representation. these results imply that the euclidean distance metric is most probably not a good estimate for similarity of faces for this task. it is interesting to note that the simple linear regressor performed as good as or better than the knn predictor. however, this effect may be attributed to our feature selection method, ranking features by the absolute value of their correlations with the target, which is optimal for linear regression. figure : prediction results obtained with pixel images (left) and with feature-based representation (right). performance is measured by the correlation between the predicted ratings and the human ratings. . . significance of results all predictors performed better with the feature-based representation than with the pixel images (in accordance with results of classification task). using the feature vectors enabled a maximum correlation of nearly . vs. a correlation of . with the pixel images. to check the significance of this score, we produced an empirical distribution of feature-based prediction scores with random ratings. the entire preprocessing, feature selection and prediction process was run times, each time with a different set of randomly generated ratings, sampled from a normal distribution with mean and variance identical to those of the human ratings. for each run, the score taken was the highest correlation of predicted ratings with the original (random) ratings. the average correlation achieved with random ratings was . and the maximum correlation was . . figure (a) depicts the histogram of these correlations. using qqplot, we verified that the empirical distribution of observed correlations is approximately normal; this is shown in figure (b). using the normal approximation, the correlation of . obtained by our feature-based predictor is significant to a level of α= . . the numbers and figures presented are for the knn predictor. correlations achieved with linear regression have different mean and standard deviation, but a similar z- value. the distribution of these correlations was also verified to be approximately normal and the correlation achieved by our linear regressor was significant to the same level of α= . . this test was not run for the svm predictor due to computational limitations. figure : correlations achieved with random ratings: (a) histogram of correlations (left), (b) qqplot of correlations vs. standard normal distributed data (right). correlations were obtained with knn predictor. . . hybrid predictor ratings predicted with the two representations were very different; the best ratings achieved using each representation had a correlation of only . - . . the relatively low correlation between the feature-based and pixel-based predictions suggests that results might be improved by using the information learned from both representations. therefore, an optimal weighted average of the best feature- based and pixel-based ratings was calculated. we produced a hybrid machine that generates the target rating , where is the rating of the feature-based predictor, is the prediction of the pixel-based machine and ≤ α ≤ . figure shows the correlation between the hybrid machine ratings and the human ratings as a function of the weights tried (weights shown are those of the feature-based ratings, α). the hybrid predictor was constructed using the best feature-based and pixel-based ratings obtained with linear regression. as evident from the graph, the best weighted ratings achieve a pixelfeaturehybrid yyy ) ( αα −+= featurey pixely figure : correlation of the weighted machine ratings with human ratings vs. the weighting parameter, α. correlation of . with the human ratings. the hybrid predictor with the optimal value of α = . improves prediction results by nearly % over those achieved with a single representation. its normalized mse is . , lower than that of the individual rating sets. these weighted ratings have the highest correlation and lowest normalized mse with the human scores. therefore, in subsequent analysis we use these weighted ratings as the best machine-predicted ratings, unless stated otherwise. . . evaluation of predicted rating ranking an additional analysis was performed to evaluate the relative image ranking induced by the best machine predictions. figure shows the probability of error in the predicted relative ordering of two images as a function of the absolute distance d in their original, human ratings. the distances were binned into bins. the probability of error, for each distance d, was computed over all pairs of images with an absolute difference of d in their human ratings. as evident from the graph, the probability decreases almost linearly as the absolute difference in the original ratings grows (the small peak observed at a distance of . is insignificant and stems from one erroneous relative ranking). . . the learning curve of facial attractiveness for further evaluation of the prediction machine, an additional experiment was run, in which we examined the learning curve of our predictor. we produced this curve by iteratively running the predictor for a growing dataset size, in the following manner: the number of input images, n, was incremented from to the entire images. for every n, the predictor was run ten times, each time with n different, randomly selected images (for n= all images were used in a single run). testing was performed on the subsets of n images only, using leave-one-out, and results were evaluated according to the correlation of the predicted ratings figure : probability of error in the predicted relative order of two images as a function of the absolute difference in their original, human ratings. with the human ratings of these images. figure shows the results for the knn redictor trained using the feature representation with k= and m= features. the are the average over the ten runs. the figure clearly shows that the performance of the predictor improves with the increase in the number of images. the slope of the graph is positive for every n≥ . similar ehavior was observed with other parameters and learners. this tendency is less istinct in the corresponding graph for the pixel images. p correlations shown in the plot b d figure : accuracy of prediction as a function of the training-set size discussion this paper presents a predictor of facial attractiveness, trained with fema e facial images and their respective average human ratings. images were represented both as raw pixel data and as measurements of key facial features. prediction was carried out using knn, svm and linear regression, and the best predicted ratings achieved a correlation of . with the human ratings. we consistently found that the measured facial features were more informative for attractiveness prediction, on all tasks tried. in addition to learning facial attractiveness, we also examined some cha riments. in particular, we ran our predictor on the "average" face, i.e. the mathematical average of the faces in the dataset. this face received only an average rating, showing no support for the averageness hypothesis in our setting. this strengthens previous experiments that argued against the averageness hypothesis (as described in section . . ). the high attractiveness of composite faces may be attributable to their smooth skin and symmetry and not to the averageness itself, explaining the fact that the mathematical average of the faces was not found to be very attractive. given the high dimensionality and redundancy of visual data, the task of learning facial attractiveness is undoubtedly a difficult one. we tried additional preprocessing, feature selection and learning methods, e.g. wrapper (kohavi & john, ), isomap (tenenbaum, de silva & langford, ) and kernel pca l racteristics found correlated with facial attractiveness in previous expe (scholkopf, smola & muller, ), but these all produced poorer results. the non-linear feature extraction methods probably failed due to an insufficient number of training examples, as they require a dense sampling of the underlying manifold. nevertheless, our predictor ach ent in the predictor’s performance as the num ieved significant correlations with the human ratings. however, we believe our success was limited by a number of hindering factors. the most meaningful obstacle in our project is likely to be the relatively small size of the datasets available to us. this limitation can be appreciated by examining figure , which presents a plot of prediction performance vs. the size of the dataset. the figure clearly shows improvem ber of images increases. the slope of the graph is still positive with the images used and does not asymptotically level off, implying that there is considerable room for improvement by using a larger, but still realistically conceivable, dataset. another likely limiting factor is insufficient data representation. while the feature-based representation produced better results than the pixel images, it is, nonetheless, incomplete; it includes only euclidean distance-based measurements and lacks fine shape and texture information. the relatively lower results with the pixel images show that this representation is, likewise, not informative enough. in conclusion, this work, novel in its application of computational learning methods for analysis of facial attractiveness, has produced promising results. significant correlations with human ratings were achieved despite the difficulty of the task and several hindering factors. the results clearly show that facial beauty is a universal concept which can be learned by a machine. there are sufficient grounds to believe that future work with a moderately larger dataset may lead to an “attractiveness machine” producing human-like evaluations of facial attractiveness. acknowledgements we thank dr. bernhard fink and the ludwig-boltzmann institute for urban ethology at the institute for anthropology, university of vienna, austria, for one of the facial datasets used in this research. appendix a feature-based representation following is a list of the measurements comprising the feature-based presentation: . face length face width – at eye level . face width – at mouth level . distance between pupils . right eyebrow thickness (above pupil) . left eyebrow thickness (above pupil) . right eyebrow arch – height difference between highest point and inner edge . left eyebrow arch – height difference between highest point and inner edge . right eye height . left eye height . right eye width . left eye width . right eye size = height * width re . . ratio between and . ratio between and . ratio between and . ratio between and . left eye size = height *width . distance between inner edges of eyes . nose width at nostrils idth = ( - ) and lip lip p lip p lip ttom of lower lip to right bottom face edge from nostrils to eyebrow top) to (distance from face bottom e from nostrils to face top) to (distance from face bottom to follows) . nose length . nose size = width * length . cheekbone w . ratio between . thickness of middle of top . thickness of right side of top . thickness of left side of to . average thickness of to . thickness of lower lip . thickness of both lips . length of lips . chin length – from bottom of face to bo . right jaw length – from bottom of face . left jaw length – from bottom of face to left bottom face edge . forehead height – from nose top to top of face . ratio of (distance to nostrils) . ratio of (distanc nostrils) . symmetry indicator (description . skin smoothness indicator (description follows) s) ator was set between the eyes of each image and two indows, surrounding only mouth and eyes, were s of the axis. the symmetry measure of the image was . hair color indicator (description follow symmetry indic a vertical symmetry axis rectangular, identically-sized w extracted from opposite side calculated as ( )∑ − yx , where n i iin is the total number of pixels in each window, xi is the value of pixel i in the right window and yi is the value of the corresponding pixel in the left window. the value of the indicator grows with the asymmetry in a face. this indicator is indeed a measure of the symmetry in the facial features, as the images are all consistent in lighting and orientation. skin smoothness indicator the “smoothness” of a face was evaluated by applying a canny edge detection operator to a window from the cheek/forehead area; a window representative of the skin texture was selected for each image. the skin smoothness indicator was the average value of the output of this operation, and its value monotonously decreases with the smoothness of a face. hair color indicator a window representing the average hair color was extracted from each image. alue of the window, thus increasing ith lighter hair. the indicator was calculated as the average v w r alley, t. r. & cunningham, m. r. 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( ) configurational in introduction . the psychophysics of beauty . . beauty and the beholder . . evolutionary origins . computational beauty analysis . this work the data . image datasets . image ratings . . rating collection . . rating analysis face representation learning attractiveness . dimension reduction . . image alignment . . eigenfaces . feature selection . attractiveness prediction . . classification into two attractiveness classes . . the learners for the regression task . . results of facial attractiveness prediction . . significance of results . . evaluation of predicted rating ranking . . the learning curve of facial attractiveness discussion acknowledgements we thank dr. bernhard fink and the ludwig-boltzmann institut appendix a feature-based representation references in the s, the developmental biologist and geneticist ch waddington coined the concept of ‘developmental stability’, or the robustness of the phenotype against genetic and environmental perturbations [ , ]. it has been claimed that this robustness, termed ‘canalization’, has evolved under natural selection to stabilize pheno- types and decrease their variability. �is is achieved by buffering the expression of traits, holding them near their optimal states despite genetic and environmental perturbations. canalization also allows the accumulation of ‘cryptic genetic variation’ caused by mutations that do not affect the phenotype. canalized traits are pheno- typically expressed only in particular environments or genetic backgrounds and become available for natural selection, a mechanism that can lead to the assimilation of novel traits. it was found some years ago that reduction in the function of the hsp protein in drosophila (whether by mutation or by specific inhibitors) apparently uncovered previously silent genetic variation, which led to an increase in morphological variation [ ]. hsp is a chaperone and heat-shock protein, which in drosophila is encoded by the hsp gene. �e morphological changes could become fixed and stably transmitted even if wild-type hsp function were restored in subsequent generations. �ese findings implied that functional hsp is a capacitor (that accumulates cryptic genetic variation and releases it under certain circumstances) that masks the effect of hidden or pre-existing genetic variation (figure ). �e hsp story in flies has become very complicated, however. recent studies have shown that the buffering by hsp is limited to specific morphological traits and does not affect others. �is supports the idea that numerous mechanisms are involved in developmental buffering, and that hsp is just one of many capacitors for genetic variation [ , ]. in addition, hsp is a very abundant protein, in some cells accounting for up to % of the total protein content, and a reduction in hsp activity affects the expression levels of numerous genes. a new study that implicates hsp in the repression of transposon- mediated mutagenesis now further complicates the story. in work recently published in nature, specchia et al. [ ] show that biogenesis of the small piwi-interacting rna (pirna) in drosophila depends on the activity of hsp . �ese results are of interest not only for the insights they provide into the molecular pathways of pirna produc- tion, but also because they imply that hsp prevents phenotypic variation by suppressing de novo mutation caused by the activity of transposons in the germline, one of the known roles of the pirnas in drosophila. �is calls for current ideas on the buffering role of hsp in flies to be revisited. pirnas are one class of the numerous small rnas (around to nucleotides long) that are expressed by eukaryotic cells and that trigger sequence-specific gene silencing called rna silencing [ , ]. by base pairing with target mrnas, the small rnas guide inhibitory complexes based on members of the argonaute class of proteins (which includes the piwi proteins) to the mrnas, resulting in mrna destruction or the inhibition of translation. rna silencing is thought to have evolved as a form of nucleic-acid-based immunity to inactivate parasitic and pathogenic invaders such as viruses and transposable elements (transposons) [ ]. in drosophila, the endogenous small interfering rna (esirna) pathway of rna silencing restrains the expression of transposons in somatic cells, whereas the pirna pathway represses transposon activity in germline cells. transposons are generally considered as ‘selfish dna’ elements usually hidden from sight. �ey can move around the genome, transposing into new sites and causing insertion mutations that are frequently deleteri- ous. �us, host genomes have evolved multiple mecha- nisms for regulating transposons, including rna silencing. abstract the heat-shock protein (hsp ) is currently thought to bu�er eukaryotic cells against perturbations caused by pre-existing cryptic genetic variation. a new study suggests that the bu�ering function of hsp could instead be due to its repression of de novo transposon- mediated mutagenesis. © biomed central ltd is canalization more than just a beautiful idea? kaoru sato and haruhiko siomi* r e s e a r c h h i g h l i g h t *correspondence: awa @sc.itc.keio.ac.jp department of molecular biology, keio university school of medicine, shinanomachi, shinjuku-ku, tokyo - , japan sato and siomi genome biology , : http://genomebiology.com/ / / / © biomed central ltd transposition is also potentially adaptive by occasionally providing a source of genetic diversity [ ]. thus, a trans posable element is often defined as a natural, endogenous, genetic toolbox for mutagenesis. in addition, transposon defense mechanisms have recently been shown to be co opted or borrowed to provide additional regulatory complexity for host genes [ ]. the production of esirnas from their longer precursor transcripts requires the processing activity of the ribonuclease dicer. by contrast, the production of pirnas is independent of dicer. drosophila has three distinct piwi proteins, ago , aubergine, and piwi, all of which exhibit the small rnaguided ribonuclease (‘slicer’) activity. deep sequencing and bioinformatic analyses of drosophila pirnas suggest a model for pirna biogenesis in which piwi subfamily proteins guide the ’ end formation of pirnas by reciprocally cleaving or slicing long sense and antisense transcripts of transposons. thus, in this amplification loop, which is called the pingpong cycle, transposons are both a source of pirnas and a target of pirnamediated silencing. however, classification of pirnas according to their origins indicated that pirnas derived from a particular pirna cluster locus are exclusively loaded onto one of the piwi proteins, piwi, indicating that those pirnas are produced by a pathway independent of the pingpong cycle. this pathway is called the primary processing path way [ , ]. the mechanism of their production, however, has been largely unclear. during spermatogenesis in drosophila males, antisense pirnas derived from the repetitive suppressor of stellate [su(ste)] locus on the y chromosome silence the xlinked stellate locus. in su(ste) and pirna pathway mutants, pirnas targeting stellate are lost, causing crystals of stellate protein to form in primary spermatocytes [ ]. specchia et al. [ ] found that mutations in the hsp gene encoding hsp , or treatment with the specific hsp inhibitor geldanamycin also caused the accumu lation of crystalline aggregates in primary spermatocytes, suggesting that hsp is involved in a pirnamediated mechanism that silences the expression of repetitive sequences and transposons. consistent with this, the authors found that hsp mutations result in a marked reduction in the accumulation of pirnas corresponding to su(ste) and various transposon sequences. conversely, the expression of various types of transposons was upregulated in both the ovaries and the testes of hsp mutants. these results showed that hsp represses the expression of transposons through pirnamediated mechanisms (figure a). specchia et al. [ ] examined the effect of hsp mutations on transposon mobility in individual flies and found that in homozygous hsp null mutants, several transposons had jumped into new sites within the genome. they further showed that approximately % of hsp mutants screened ( out of , flies) exhibited morphological abnormalities. together, these findings suggested that the phenotypic variation observed among figure . a model for the buffering role of hsp in canalization. hsp conceals cryptic genetic mutations. (a) when hsp is normal, underlying genetic variation (gray peaks) is hidden and genetic signal inputs (black peaks) are outputted normally, resulting in a phenotype that varies within normal limits. (b) when hsp is impaired, hidden genetic variation is revealed, resulting in altered genetic signal inputs (black peaks) that are abnormally outputted. these altered outputs may lead to an abnormal phenotypic variation. normal hsp function reduced hsp function g e n e tic s ig n a l i n te n si ty g e n e tic s ig n a l i n te n si ty genetic variationgenetic variation v a n a tio n in p h e n o typ e v a n a tio n in p h e n o typ e (a) (b) sato and siomi genome biology , : http://genomebiology.com/ / / / page of hsp mutants could be due to de novo mutations produced by activated transposable elements rather than to the buffering of preexisting cryptic genetic variation. for example, among the abnormalities observed by specchia et al. [ ] among their hsp mutants was a fly resembling the scutoid phenotype (in which there is a loss of bristles from the head and thorax of the adult), which is caused by a mutation in the noc gene. the authors demonstrated that the coding sequence of the noc gene in this fly was indeed interrupted by an i- elementlike transposon sequence. this indicates that the scutoid phenotype found in the screen was caused by a de novo mutation and not by the expression of a pre existing genetic variation (figure b). as well as suggesting that a reinterpretation of the buffering role of hsp [ ] might be needed, these new findings also provide evidence supporting a model in which hsp is involved in the control of transposon activity in germ cells by affecting pirna biogenesis. pirnas in drosophila are produced almost exclusively in germ cells from intergenic repetitive genes, transposable elements and pirna clusters by two pathways: the primary processing pathway, and the amplification ‘ping pong’ loop [ , ]. mature pirnas are loaded onto the piwi subfamily of argonaute proteins, and the amplifi cation loop is known to be independent of dicer but dependent on the slicer activity of piwi proteins. however, the mechanisms of primary pirna processing remain elusive. how does hsp function in pirna biogenesis and which of the two pirna production pathways is it involved in? hsp can, for example, be co purified with the slicer activity of ago , one of the mammalian argonaute proteins [ ]. hsp could play a role in the biogenesis of small silencing rnas either as a chaperone for the correct folding of the argonaute proteins or by providing an assembly platform for components of the small rna biogenetic machinery to promote the loading of small rnas onto the argonaute proteins. it will be important to ascertain whether hsp interacts with the piwi proteins in flies and has a role in their function, such as ensuring their correct cellular localization, and also whether mutations in hsp affect either or both of the two pirna biogenesis pathways. it will also be interesting to examine whether hsp is required for the esirna pathway that silences transposable elements in somatic cells. further investigation should reveal the role of hsp in rna silencing and help expand our understanding of transposon regulation by rna silencing pathways. published: march references . flatt t: the evolutionary genetics of canalization. q rev biol , : - . . hornstein e, shomron n: canalization of development by micrornas. nat genet , :s -s . . rutherford rl, lindquist s: hsp as a capacitor for morphological evolution. nature , : - . figure . hsp functions in the suppression of transposon-mediated ‘canonical’ mutagenesis via the pirna pathway. (a) activated transposons can move from one site in a genome to another by the process of transposition and so have the potential to induce de novo gene mutations by insertion. hsp could be involved in the control of transposition by affecting pirna biogenesis. (b) reduced hsp function leads to transposon-mediated insertional mutagenesis and the induction of morphological variability, such as variation in eye and body color. reduced hsp function decrease of pirnas transposon activation transposon insertional mutagenesis phenotypic variation transposon hsp (piwi proteins) pirna transposon silencing insertional mutagenesis (a) (b) sato and siomi genome biology , : http://genomebiology.com/ / / / page of . specchia v, piacentini l, tritto p, fanti l, d’alessandro r, palumbo g, pimpinelli s, bozzetti mp: hsp prevents phenotypic variation by suppressing the mutagenic activity of transposons. nature , : - . . siomi h, siomi mc: on the road to reading the rna interference code. nature , : - . . ghildiyal m, zamore pd: small silencing rnas: an expanding universe. nat rev genet , : - . . girard a, hannon gj: conserved themes in small-rna-mediated transposon control. trends cell biol , : - . . kazazian hh jr: mobile elements: drivers of genome evolution. science , : - . . siomi h, siomi mc: interactions between transposable elements and argonautes have (probably) been shaping the drosophila genome throughout evolution. curr opin genet dev , : - . . liu j, carmell ma, rivas fv, marsden cg, thomson jm, song jj, hammond sm, joshua-tor l, hannon gj: argonaute is the catalytic engine of mammalian rnai. science , : - . doi: . /gb- - - - cite this article as: sato k, siomi h: is canalization more than just a beautiful idea? genome biology , : . sato and siomi genome biology , : http://genomebiology.com/ / / / page of abstract references sex, race, age, and beauty as factors in recognition of faces sex, race, age, and beauty as factors in recognition of faces* john f. cross,t jane cross, and james daly saint louis university, st. louis, missouri three hundred ss, black and white, male and female, at four age levels were tested for their recognition of photographed faces: black, white, male, female, child, adolescent, and adult. females recognized female faces more frequently than the male faces, while male ss recognized the male and female faces with equal facility. whites recognized the white faces more frequently than the black faces, while black ss recognized the black and white faces with equal facility. incorrect identifications of faces not actually seen before were treated separately. male faces and black faces were misidentified more than white faces and female faces. the number of false identifications of faces decreased as ss increased in age. perceived beauty in a face facilitated recognition. there was evidence of large differences in memorability among individual faces. adolescents, and adults in their s and s. the portraits, each about in. square, were arranged randomly on an x in. card in a matrix containing faces, presenting two faces from each of the age-sex-race categories. two such composites were made. twelve of the faces, one from each category, were common to both cards and each card had additional faces not appearing on the other card. the consequence of this arrangement of stimuli was that the stimulus sample for recognition included six portraits of males, of females, of blacks, and of whites, and four portraits at each age level. the sample of portraits subject to misidentification was doubled for each category of portrait since different faces appeared in the two matrices. to many uninitiated observers all babies tend to look alike, as do most orientals. experience with a group usually leads the observer to make the many fine discriminations possible until he ultimately discovers that the group is composed of individuals with infinitely variable and memorable facial characteristics. recognition of faces is a complex perceptual achievement with practical applications ranging from identification of criminals to social success at cocktail parties. in the recent literature there are few studies in this area. howells ( ) reported that women were superior to men and sales personnel superior to farmers. he found a correlation of . with iq of the s. seeleman ( ) found that among white ss, unfavorable attitudes toward negroes were related to poor memory for black faces. goldstein and chance ( ) report that -year-old children found it easier to recognize younger faces than those of the same age or older, but that other age groups of children were not affected by the age of the photographed face. malpass and kravitz ( ), working with black and white college students, found that white faces were recognized more frequently than were black faces, but that there was a significant interaction between race of the s and race of the stimulus. ss having more experience with the opposite race recognized faces of that race more frequently than more racially segregated ss. *this research was supported by u.s. public health service grant mh - . the authors wish to thank the ss who gave their time to this project, and the faculty of each of the participating schools for their cooperation and help. trequests for reprints should be sent to john f. cross, who is now chairman of the social sciences division, college of the virgin islands, st. thomas, u.s. virgin islands . malpass and kravitz concluded that experience with persons of a given race was related to ability to recognize faces of that race. the present study was concerned with the ability of individuals, black and white, male and female, children, adolescents, and adults from racially segregated and racially integrated backgrounds, to recognize a wide range of facial types. the relation of perceived attractiveness of faces to their recognizability was investigated as were differences in recognizability between individual faces. method subjects three hundred ss, consisting of individuals at each of three age levels- , , and years-and a group of adults whose mean age was , were interviewed individually. in each of the first three age groups there were black children and white children. within these groups, half lived in racially segregated communities and attended uniracial schools, while the other half lived in racially integrated urban neighborhoods and attended integrated schools. the adult group consisted of white adults and black adults from the same communities and neighborhoods as the younger ss, equal numbers of males and females were included in each s group. stimulus material the photographic portraits used were selected at random from high school year books and school portraits of grade school children and their teachers. highly unusual facial expressions, hair styles, or clothing, or persons with eyeglasses, were screened. black and white faces of both sexes were represented at three age levels, -year-old children, -year-old procedure before testing, ss were assigned randomly to one of two orders, and to either the male or female examiner. the s was told that we were studying beauty, that we were interested in which faces he thought were pretty or handsome or beautiful, and that we were trying to discover what sorts of faces were attractive to different kinds of people and whether or not a person's ideas of beauty changed with age. the s was not told that he would be asked to recall any of the faces. the s was then shown one of the two group pictures. he was requested to look at all the faces and to pick which, if any, he considered pretty, handsome, or beautiful. the s was allowed to pick as many faces as he wished, with as much time as he needed. if the s acted hastily, he was gently encouraged to examine all the faces carefully. the s was then given, as an intervening task, a series of groups of six faces to look at. judge, and finally rate for beauty. this procedure provided data for a separate study of the perception of beauty in faces, but served for the present study as a simulation of the real-world experience of seeing many faces before encountering the need to recall a previously seen face. the s was then shown the second matrix of portraits containing faces seen previously and new faces. s was asked which of the faces had been shown before. results results for correct recognitions and incorrect identifications were analyzed separately. for the sake of clarity, the results are presented in four general areas: ( ) the effects and interactions of sex of the face and age and sex of the s on recognition and misidentification of faces; ( ) the effect and interaction of race of face perception & psychophysics, , vol. ( ) copyright , psychonomie society, inc., austin, texas table memory for faces of the same and other sex and the same and other race table memory for male and female faces by male and female ss at different ages percent correct percent incorrect recognition identification age of s type of face a a male ss male faces female faces all faces female ss male faces femalefaces all faces perception & psychophysics, , vol. ( race variables in recognition and false identification recognition of black and white faces by black and white ss was evaluated in a two-way anov a with one repeated measure. equal numbers of male and female ss at four age levels were included. while neither of the main effects reached statistical significance, the interaction of race of face by race of s was significant at the . level (f = . , df = / ). black ss recognized black and white faces almost equally well, but white ss demonstrated poorer recognition of black faces and better recognition of white faces, as seen in table . the data on misidentification indicates that both black and white ss made more false identifications of black faces than of white faces. the two-way anov a on the misidentification data revealed the main effect of race of face to approach significance (f = . , df = / , p < . ). half of our ss lived in racially integrated neighborhoods and half in uniracial communities. the data of two of the s groups, the -year-olds and the -year-olds, whose level of integration or segregation would be most precisely defined in terms of school population, were combined and analyzed in terms of the differences in recognition of black and white faces relative to the racial environment of the s. these data are presented in table . for black adolescents, racial environment seemed to have no measurable effect on recognition ability. both integrated and segregated black adolescents recognized black and white faces with equal facility. black faces were incorrectly identified more often than white faces. this was true for both integrated and segregated black adolescents. both these results repeat the overall pattern noted in this study for black ss of all ages. for white adolescents, however, racial segregation or integration was related to recognition ability. while both integrated and segregated white ss recognized more white faces than black faces, the segregated white adolescents recognized significantly more white faces than did ss from percent "attractive" faces correctly recognized maless whitess female ss black ss percent incorrect identification sex and age effects in misidentification of faces a three-way anov a with two repeated measures was done for incorrect identification of male and female faces by male and female ss at four age levels. in table it can be seen that both male and female ss falsely identified male faces more frequently than female faces, and that females made slightly more errors in identification than did male ss. in the anov a, for misidentifications, however, the main effects of sex of face and sex of s were not statistically significant, nor was the interaction of these two variables. age of s was a highly significant variable (f = . , df = / , p < . ). for both male and female ss the tendency was for fewer false identifications with increasing age. although male and female ss were similar in their performance at age levels of , , and adult, the -year-old girls made many more errors in identification than did -year-old boys. this is largely the basis of the significant age of s by sex of s interaction (f = . , df = / , p<. ). percent correct type of face recognition male faces female faces malefaces female faces black faces whitefaces black faces whitefaces and race of the s on recognition and misidentification; ( ) the relation between perceived beauty of the face and recognition; and ( ) differences between individual faces. generalizations concerning the facial variables are limited because of the small sample of portraits used. effects of sex and age on recognition percent correct recognition of the male and female faces by male and female ss at different ages was analyzed in a three-way anov a with two repeated measures (winer, , p. ). each cell of the by by (sex of face and sex of s and age of s) analysis contained the proportion of correct recognitions for each of the six faces used. both black and white ss were included. while female ss (n = ) recognized more faces than did male ss (n = ), and while the female faces (n = ) were recognized more frequently than the male faces (n = ), neither sex of s nor sex of face were significant main effects. the sex of face by sex of s interaction was significant beyond the . level (f = . , df = / ). this result is more easily understood by referring to the percent of correct recognitions of male and female faces presented in table . male ss recognized the male and female faces with equal facility, while female ss recognized the male faces less often than did males and recognized the female faces more often. the age of s main effect was not statistically significant (f = . , df = / , p < . ). when male and female results are seen separately in table , there is seen a slight improvement in recognition with age for males, while for females there is a slight decrease in correct recognitions with increasing age. this age of s by sex of s interaction was statistically significant (f = . , df = / , p < . ). table memory for black and white faces by segregated and integrated black and wh;t" ss racially integrated schools (z = . , p < . ). predictably, segregated white adolescents made more false identifications of black faces than of white faces. the incorrect identifications of the integrated white ss, however, were equally divided between black and white faces, an exception to the otherwise consistent finding of more false identification of black than of white faces. effect of perceived beauty on recognition of faces the initial task presented to each s was to choose from the first matrix of faces any which he considered pretty, handsome, or beautiful. table indicates the percentage ~f correct recognitions of faces by ss who reported those faces attractive in comparison to the percentage of correct recognition of all ss. in every case, a higher percentage of ss who perceived beauty in a face were subsequently able to recognize the face. range of recognizability of various faces for each portrait the total number of correct identifications possible was . the most frequently recognized face, that of the -year-old white girl was recognized by slightly more than half the ss. the face least frequently recognized, that of the -year-old black male, was recognized by only % of the ss. the mean number of ss correctly recognizing a picture was , and the range was from to . for of the faces which could be misidentified, the range was from to false identifications out of a possible . the two notable exceptions were a -year-old black male face, which was falsely identified by ss, and an adult black male face, which was falsely identified by ss. although earlier work (howells, ) led us to expect that females would be better at recognizing faces than males, we found females superior only in the case of the female faces. this result might be specific to the six female faces in oor sample, but this seems unlikely ir w of the range of age and the race d.. ~rence in both our ss and our photos. possibly female ss white faces, blacks would have had ample opportunity to learn the discriminanda for both racial types, while whites would have not. the smaller difference in recognition efficiency between black and white faces found for the integrated white adolescent ss as compared to the segregated whites is consistent with this interpretation. it remains for future research to establish that there are in fact differences in the discriminanda, be they specific or more gestalt-like, between racial types. an alternative explanation of these results might be made strictly in terms of motivational factors, considering the relative importance to the s groups of the ability to distinguish within the groups of faces in question. the greater memorability of attractive faces is another result requiring further research to determine the relative weight of the various factors which may account for it. simple explanation in terms of differences in exposure time are ruled out. our ss often spent more time scrutinizing faces of doubtful beauty, finally deciding that most of these were not really pretty or handsome, than they spent examining obviously (to them) attractive faces. instructional set probably played a part in the results. while ss did not expect to be asked later to recognize specific faces, they were set for an examination of their personal standards of beauty. while they generally spent less time looking at the attractive faces, they may have given them their more active attention, especially as gestalten, which would enhance later recall of the face as a whole. the differences in memorability of individual faces was a notable result of our study. out of our sample of f aces, the most memorable was recognized three times as often as the least. of the which could be incorrectly identified, the most mistaken face was falsely identified times as often as the least. when we arrayed these faces in the order of their memorability and asked of our colleagues to identify the continua on which the faces were ordered, they could detect none. when told the basis of the ordering, out of correctly identified the high and low end of the array of faces ordered by hit frequency and out of did so for the faces ordered by false alarm frequency. at this point they were prepared to suggest that the well-remembered faces were less "ordinary" looking, while the more misidentified faces were more ..ordinary, " which suggests an interference theory of facial percent incorrect identification segregated black ss segregated white ss percent correct recognition are more attentive to female faces because of the emphasis placed on attractive female facial characteristics. the results for incorrect identifications showed few differences between male and female faces. this finding is not inconsistent with the hypothesis of sensitivity of females to female faces since, for faces not previously seen and consequently not scrutinized, no sex of s difference would be expected. while percent correct recognition did not change with age, holding around %, performance improved steadily by virtue of a decreasing false alarm rate up to the adult level. the percent correct recognition and incorrect identification is most likely quite specific to the instructions and testing conditions used, but the trend of performance related to age of s is probably a widely generalizable finding. the most obvious interpretation is that younger ss guess more than older. another explanation is that younger ss may have less ability to recall the circumstances under which a face was seen and consequently confused the faces shown them in the matrix with faces seen prior to the interview or with faces in the interpolated series. if young children are less capable of making the fine discriminations which differentiate faces, the probability of such confusion would be increased. thus, at least three factors may contribute to performance in recognition or misidentification of faces: willingness to guess, ability to make discriminations, and recall of the circumstances of the prior perception. the effect of race on recognition of faces is interpretable in the light of differences between the black and the white experience in the united states at the time that we did the testing (summer and autumn of ). american blacks, in their work and via television and movies, are virtually assured of exposure to whites. for a majority of whites the situation is reversed. these differences in exposure rates could account in part at least for the results obtained. if those details of physiognomy which provide the most salient diseriminanda between black faces are different from those between percent incorrect identification integrated white ss integrated black ss percent correct recognition black faces white faces black faces white faces type of face perception & psychophysics, , vol. ( ) memorability, more typical faces are more easily confused with previously seen faces. an interference theory would similarly account for the greater memorability of the more than typically attractive faces. a final note of concern is directed to the finding that of our faces were misidentified by so many ss. these faces did not remind our ss of any well-known persons, which might account for our result. the social significance of the finding rests in the possible consequences for persons who are atypically misidentifiable, say, for example, in a police line-up. it is interesting that the faces in question were both black males. the need for further investigation of this issue is apparent. references goldstein, a. g .. & chance, j. e. recognition of children's faces. perceptual & motor skills, , , - . howells, t. h. a study of ability to recognize faces. journal of abnormal & social psychology, , , - . malpass, n, s., & kravitz, j. recognition for faces of own and other race. journal of personality & social psychology, , , - . seeleman, v. the influence of attitude upon remembering of pictorial material. archives of psychology, , , - . winer, b. j. statistical principles in experimental design. new york: mcgraw-hill, . (accepted for publication may , .) perception & psychophysics, , vol. ( ) desy- - .dvi desy– – may beauty photoproduction using decays into electrons at hera zeus collaboration abstract photoproduction of beauty quarks in events with two jets and an electron asso- ciated with one of the jets has been studied with the zeus detector at hera using an integrated luminosity of pb− . the fractions of events containing b quarks, and also of events containing c quarks, were extracted from a likelihood fit using variables sensitive to electron identification as well as to semileptonic decays. total and differential cross sections for beauty and charm production were measured and compared with next-to-leading-order qcd calculations and monte carlo models. the zeus collaboration s. chekanov, m. derrick, s. magill, b. musgrave, d. nicholass , j. repond, r. yoshida argonne national laboratory, argonne, illinois - , usa n m.c.k. mattingly andrews university, berrien springs, michigan - , usa p. antonioli, g. bari, l. bellagamba, d. boscherini, a. bruni, g. bruni, f. cindolo, m. corradi, g. iacobucci, a. margotti, r. nania, a. polini infn bologna, bologna, italy e s. antonelli, m. basile, m. bindi, l. cifarelli, a. contin, s. de pasquale , g. sartorelli, a. zichichi university and infn bologna, bologna, italy e d. bartsch, i. brock, h. hartmann, e. hilger, h.-p. jakob, m. jüngst, a.e. nuncio-quiroz, e. paul, u. samson, v. schönberg, r. shehzadi, m. wlasenko physikalisches institut der universität bonn, bonn, germany b n.h. brook, g.p. heath, j.d. morris h.h. wills physics laboratory, university of bristol, bristol, united kingdom m m. capua, s. fazio, a. mastroberardino, m. schioppa, g. susinno, e. tassi calabria university, physics department and infn, cosenza, italy e j.y. kim chonnam national university, kwangju, south korea z.a. ibrahim, b. kamaluddin, w.a.t. wan abdullah jabatan fizik, universiti malaya, kuala lumpur, malaysia r y. ning, z. ren, f. sciulli nevis laboratories, columbia university, irvington on hudson, new york o j. chwastowski, a. eskreys, j. figiel, a. galas, m. gil, k. olkiewicz, p. stopa, l. zawiejski the henryk niewodniczanski institute of nuclear physics, polish academy of sciences, cracow, poland i l. adamczyk, t. bo ld, i. grabowska-bo ld, d. kisielewska, j. lukasik, m. przybycień, l. suszycki faculty of physics and applied computer science, agh-university of science and technology, cracow, poland p a. kotański , w. s lomiński department of physics, jagellonian university, cracow, poland i u. behrens, c. blohm, a. bonato, k. borras, r. ciesielski, n. coppola, s. fang, j. fourletova , a. geiser, p. göttlicher , j. grebenyuk, i. gregor, t. haas, w. hain, a. hüttmann, f. januschek, b. kahle, i.i. katkov, u. klein , u. kötz, h. kowalski, e. lobodzinska, b. löhr, r. mankel, i.-a. melzer-pellmann, s. miglioranzi, a. montanari, t. namsoo, d. notz , a. parenti, l. rinaldi , p. roloff, i. rubinsky, r. santamarta , u. schneekloth, a. spiridonov , d. szuba , j. szuba , t. theedt, g. wolf, k. wrona, a.g. yagües molina, c. youngman, w. zeuner deutsches elektronen-synchrotron desy, hamburg, germany v. drugakov, w. lohmann, s. schlenstedt deutsches elektronen-synchrotron desy, zeuthen, germany g. barbagli, e. gallo infn florence, florence, italy e p. g. pelfer university and infn florence, florence, italy e a. bamberger, d. dobur, f. karstens, n.n. vlasov fakultät für physik der universität freiburg i.br., freiburg i.br., germany b p.j. bussey , a.t. doyle, w. dunne, m. forrest, m. rosin, d.h. saxon, i.o. skillicorn department of physics and astronomy, university of glasgow, glasgow, united kingdom m i. gialas , k. papageorgiu department of engineering in management and finance, univ. of aegean, greece u. holm, r. klanner, e. lohrmann, p. schleper, t. schörner-sadenius, j. sztuk, h. stadie, m. turcato hamburg university, institute of exp. physics, hamburg, germany b c. foudas, c. fry, k.r. long, a.d. tapper imperial college london, high energy nuclear physics group, london, united kingdom m t. matsumoto, k. nagano, k. tokushuku , s. yamada, y. yamazaki institute of particle and nuclear studies, kek, tsukuba, japan f a.n. barakbaev, e.g. boos, n.s. pokrovskiy, b.o. zhautykov institute of physics and technology of ministry of education and science of kazakhstan, almaty, kazakhstan v. aushev , m. borodin, i. kadenko, a. kozulia, v. libov, m. lisovyi, d. lontkovskyi, i. makarenko, iu. sorokin, a. verbytskyi, o. volynets institute for nuclear research, national academy of sciences, kiev and kiev national university, kiev, ukraine ii d. son kyungpook national university, center for high energy physics, daegu, south korea g j. de favereau, k. piotrzkowski institut de physique nucléaire, université catholique de louvain, louvain-la-neuve, belgium q f. barreiro, c. glasman, m. jimenez, l. labarga, j. del peso, e. ron, m. soares, j. terrón, m. zambrana departamento de f́ısica teórica, universidad autónoma de madrid, madrid, spain l f. corriveau, c. liu, j. schwartz, r. walsh, c. zhou department of physics, mcgill university, montréal, québec, canada h a t a t. tsurugai meiji gakuin university, faculty of general education, yokohama, japan f a. antonov, b.a. dolgoshein, d. gladkov, v. sosnovtsev, a. stifutkin, s. suchkov moscow engineering physics institute, moscow, russia j r.k. dementiev, p.f. ermolov †, l.k. gladilin, yu.a. golubkov, l.a. khein, i.a. korzhavina, v.a. kuzmin, b.b. levchenko , o.yu. lukina, a.s. proskuryakov, l.m. shcheglova, d.s. zotkin moscow state university, institute of nuclear physics, moscow, russia k i. abt, a. caldwell, d. kollar, b. reisert, w.b. schmidke max-planck-institut für physik, münchen, germany g. grigorescu, a. keramidas, e. koffeman, p. kooijman, a. pellegrino, h. tiecke, m. vázquez , l. wiggers nikhef and university of amsterdam, amsterdam, netherlands h n. brümmer, b. bylsma, l.s. durkin, a. lee, t.y. ling physics department, ohio state university, columbus, ohio n p.d. allfrey, m.a. bell, a.m. cooper-sarkar, r.c.e. devenish, j. ferrando, b. foster, k. korcsak-gorzo, k. oliver, s. patel, v. roberfroid , a. robertson, p.b. straub, c. uribe-estrada, r. walczak department of physics, university of oxford, oxford united kingdom m a. bertolin, f. dal corso, s. dusini, a. longhin, l. stanco infn padova, padova, italy e p. bellan, r. brugnera, r. carlin, a. garfagnini, s. limentani dipartimento di fisica dell’ università and infn, padova, italy e b.y. oh, a. raval, j. ukleja , j.j. whitmore department of physics, pennsylvania state university, university park, pennsylvania o iii y. iga polytechnic university, sagamihara, japan f g. d’agostini, g. marini, a. nigro dipartimento di fisica, università ’la sapienza’ and infn, rome, italy e j.e. cole , j.c. hart rutherford appleton laboratory, chilton, didcot, oxon, united kingdom m h. abramowicz , r. ingbir, s. kananov, a. levy, a. stern raymond and beverly sackler faculty of exact sciences, school of physics, tel aviv university, tel aviv, israel d m. kuze, j. maeda department of physics, tokyo institute of technology, tokyo, japan f r. hori, s. kagawa , n. okazaki, s. shimizu, t. tawara department of physics, university of tokyo, tokyo, japan f r. hamatsu, h. kaji , s. kitamura , o. ota , y.d. ri tokyo metropolitan university, department of physics, tokyo, japan f m. costa, m.i. ferrero, v. monaco, r. sacchi, a. solano università di torino and infn, torino, italy e m. arneodo, m. ruspa università del piemonte orientale, novara, and infn, torino, italy e s. fourletov , j.f. martin, t.p. stewart department of physics, university of toronto, toronto, ontario, canada m s a a s.k. boutle , j.m. butterworth, c. gwenlan , t.w. jones, j.h. loizides, m. wing physics and astronomy department, university college london, london, united kingdom m b. brzozowska, j. ciborowski , g. grzelak, p. kulinski, p. lużniak , j. malka , r.j. nowak, j.m. pawlak, t. tymieniecka, a. ukleja, a.f. żarnecki warsaw university, institute of experimental physics, warsaw, poland m. adamus, p. plucinski institute for nuclear studies, warsaw, poland y. eisenberg, d. hochman, u. karshon department of particle physics, weizmann institute, rehovot, israel c e. brownson, t. danielson, a. everett, d. kçira, d.d. reeder, p. ryan, a.a. savin, w.h. smith, h. wolfe department of physics, university of wisconsin, madison, wisconsin , usa n s. bhadra, c.d. catterall, y. cui, g. hartner, s. menary, u. noor, j. standage, j. whyte department of physics, york university, ontario, canada m j p a iv also affiliated with university college london, uk now at university of salerno, italy supported by the research grant no. p b ( - ) this work was supported in part by the marie curie actions transfer of knowledge project cocos (contract mtkd-ct- - ) now at university of bonn, germany now at desy group feb, hamburg, germany now at university of liverpool, uk now at cern, geneva, switzerland now at bologna university, bologna, italy now at bayesforecast, madrid, spain also at institut of theoretical and experimental physics, moscow, russia also at inp, cracow, poland also at fpacs, agh-ust, cracow, poland partly supported by moscow state university, russia royal society of edinburgh, scottish executive support research fellow also affiliated with desy, germany also at university of tokyo, japan now at kobe university, japan supported by desy, germany partly supported by russian foundation for basic research grant no. - - - nsfc-a eu marie curie fellow partially supported by warsaw university, poland this material was based on work supported by the national science foundation, while working at the foundation. now at university of kansas, lawrence, usa also at max planck institute, munich, germany, alexander von humboldt research award now at kek, tsukuba, japan now at nagoya university, japan department of radiological science, tokyo metropolitan university, japan now at sunmelx co. ltd., tokyo, japan pparc advanced fellow also at hamburg university, inst. of exp. physics, alexander von humboldt research award and partially supported by desy, hamburg, germany also at lódź university, poland lódź university, poland now at lund universtiy, lund, sweden † deceased v a supported by the natural sciences and engineering research council of canada (nserc) b supported by the german federal ministry for education and research (bmbf), under contract numbers hz pda, hz gua, hz vfa and hz kha c supported in part by the minerva gesellschaft für forschung gmbh, the is- rael science foundation (grant no. / - . ) and the u.s.-israel binational science foundation d supported by the israel science foundation e supported by the italian national institute for nuclear physics (infn) f supported by the japanese ministry of education, culture, sports, science and technology (mext) and its grants for scientific research g supported by the korean ministry of education and korea science and engi- neering foundation h supported by the netherlands foundation for research on matter (fom) i supported by the polish state committee for scientific research, project no. desy/ / - /des/ / j partially supported by the german federal ministry for education and re- search (bmbf) k supported by rf presidential grant n . . for the leading scientific schools and by the russian ministry of education and science through its grant for scientific research on high energy physics l supported by the spanish ministry of education and science through funds provided by cicyt m supported by the science and technology facilities council, uk n supported by the us department of energy o supported by the us national science foundation. any opinion, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the national science foundation. p supported by the polish ministry of science and higher education as a scien- tific project ( - ) q supported by fnrs and its associated funds (iisn and fria) and by an inter-university attraction poles programme subsidised by the belgian federal science policy office r supported by the malaysian ministry of science, technology and innova- tion/akademi sains malaysia grant saga - - - vi introduction the production of heavy quarks in ep collisions at hera is an important testing ground for perturbative quantum chromodynamics (pqcd) since the large b-quark and c-quark masses provide a hard scale that allows perturbative calculations. when q , the negative squared four-momentum exchanged at the electron or positron vertex, is small, the re- actions ep → ebbx and ep → eccx can be considered as a photoproduction process in which a quasi-real photon, emitted by the incoming electron interacts with the proton. the corresponding leading-order (lo) qcd processes are the direct-photon process, in which the quasi-real photon enters directly in the hard interaction, and the resolved- photon process, in which the photon acts as a source of partons which take part in the hard interaction. for heavy-quark transverse momenta comparable to the quark mass, next-to-leading-order (nlo) qcd calculations in which the massive quark is generated dynamically [ , ] are expected to provide reliable predictions for the photoproduction cross sections. beauty and charm quark production cross sections have been measured using several different methods by both the zeus [ – ] and the h [ – ] collaborations. both the deep inelastic scattering (dis) and photoproduction measurements are reasonably well described by nlo qcd predictions. most of the previous measurements of b-quark production used muons to tag semileptonic decays of the b hadrons. the identification of electrons close to jets is more difficult than for muons, but the electrons can be identified down to lower momenta. a first measurement of b-quark photoproduction from semileptonic decays to electrons (e−) was presented in a previous publication [ ], which used the e+p collision data from the – running period corresponding to an integrated luminosity of pb− . this paper presents an extension of this measurement exploiting semileptonic decays to electrons as well as to positrons for data taken with both e−p and e+p collisions using three times the integrated luminosity. the production of electrons from semileptonic decays (esl), in events with at least two jets (jj) in photoproduction, ep → ebbx → ejj esl x′, was measured in the kinematic range q < gev and gev < wγp < gev, where wγp is the centre-of-mass energy of the γp system. the likelihood method used to extract the b-quark cross sections also allowed the corresponding c-quark cross sections to be extracted. this paper provides a complementary study to the measurements using muon decays. hereafter unless explicitly stated both electrons and positrons are referred to as electrons. experimental set-up this analysis was performed with data taken from to , when hera collided electrons or positrons with energy ee = . gev with protons of energy ep = gev ( – ) or gev( – ). the corresponding integrated luminosities are . ± . pb− at centre-of-mass energy √ s = gev, and . ± . pb− at √ s = gev. a detailed description of the zeus detector can be found elsewhere [ ]. a brief outline of the components that are most relevant for this analysis is given below. charged particles were tracked in the central tracking detector (ctd) [ ], which operated in a magnetic field of . t provided by a thin superconducting coil. the ctd consisted of cylindrical drift chamber layers, organised in nine superlayers covering the polar- angle region ◦ < θ < ◦. the transverse-momentum resolution for full-length tracks is σ(pt )/pt = . pt ⊕ . ⊕ . /pt , with pt in gev. the pulse height of the sense wires was read out in order to estimate the ionisation energy loss per unit length, de/dx (see section ). the high-resolution uranium–scintillator calorimeter (cal) [ ] consisted of three parts: the forward (fcal), the barrel (bcal) and the rear (rcal) calorimeters. each part was subdivided transversely into towers and longitudinally into one electromagnetic sec- tion and either one (in rcal) or two (in bcal and fcal) hadronic sections. the smallest subdivision of the calorimeter is called a cell. the cal energy resolutions, as measured under test-beam conditions, are σ(e)/e = . / √ e for electrons and σ(e)/e = . / √ e for hadrons, with e in gev. the luminosity was measured from the rate of the bremsstrahlung process ep → eγp, where the photon was measured in a lead–scintillator calorimeter [ ] placed in the hera tunnel at z = − m. de/dx measurement a central tool for this analysis was the de/dx measurement from the ctd. the pulse height of the signals on the sense wires was used to measure the specific ionisation. this pulse height was corrected for a number of effects [ ]. such as a factor / sin θ due to the zeus coordinate system is a right-handed cartesian system, with the z axis pointing in the proton beam direction, referred to as the “forward direction”, and the x axis pointing left towards the centre of hera. the coordinate origin is at the nominal interaction point. the pseudorapidity is defined as η = − ln ( tan θ ) , where the polar angle, θ, is measured with respect to the proton beam direction. the azimuthal angle, φ, is measured with respect to the x axis. the projection of the track onto the direction of the signal wire, the space-charge effect caused by the overlap of the ionisation clouds in the avalanche, and the dependence of the pulse shape on the track topology. an additional correction was needed for hits close to the end-plates of the ctd. if a hit followed a previous one on the same wire within ns, its pulse could be distorted: such hits were rejected. the event topology was used to identify additional double hits that could not be resolved; the de/dx measurement was corrected accordingly. the de/dx value of a track was calculated as the truncated mean value of the individual measurements, corrected as discussed above, after rejecting the lowest % and the highest % of the measurements. hits where the measured pulse height was in saturation were always rejected in forming the mean. corrections were applied for the finite number of hits and whenever more than % of the hits were saturated. the corrected de/dx measurement was normalised in units of mip (minimum ionising particles) such that the minimum of the de/dx distribution was . mip. electrons are expected to have a mean value of about . mip in the momentum range studied here. different samples of identified particles were used to calibrate and validate the de/dx measurement. the samples used for calibration were: • e± from photon conversions, j/ψ decays and dis electrons; • π± from k decays with . gev < p < gev, where p is the measured track momen- tum. the samples used for validation were: • π± from k outside the momentum range used for the calibration sample, as well as π± from ρ , Λ and d∗ decays; • k± from φ and d∗ decays; • p,p from Λ decays; • cosmic µ±. typical sample purities were above % for the calibration samples and well above % for the validation samples [ ]. after all corrections, the measured de/dx depended only on the particle velocity, βγ. this is illustrated in fig. . it shows the specific energy loss as a function of βγ, for the different samples of identified particles, e±,µ±,π±,k±,p,p. all particle types are well described using a single physically motivated parametrisation of the mean energy loss as a function of βγ with five free parameters following allison and cobb (ac) [ ]. given the quality of the description of the mean de/dx by the ac parametrisation, the measurements can be used to determine residuals on de/dx. as an example, the distribution of residuals for a sample of tracks with the number of hits after truncation, ntrunc, equal to is shown in fig. . the de/dx resolution is typically % for tracks that pass at least five superlayers. it improves to about % for tracks that pass all superlayers. monte carlo simulation to evaluate the detector acceptance and to provide the signal and background distri- butions, monte carlo samples of beauty, charm and light-flavour events generated with pythia . [ ] were used. the production of bb-pairs was simulated following the standard pythia prescription with the following subprocesses [ ]: • direct and resolved photoproduction with a leading-order massive matrix element; • b excitation in both the proton and the photon with a leading-order massless matrix element. the cteq l [ ] parton distributions were used for the proton, while grv-g lo [ ] was used for the photon. the b-quark mass parameter was set to . gev. the production of charm and light quarks was simulated for both direct and non-direct photoproduction with leading-order matrix elements in the massless scheme using the same parton distributions as for the bb samples. the generated events were passed through a full simulation of the zeus detector based on geant . [ ]. the ionisation loss in the ctd was treated separately using a parametrisation of the measured data distributions based on the calibration sample [ , ]. the final monte carlo events had to fulfil the same trigger requirements and pass the same reconstruction programme as the data. data selection events were selected online with a three-level trigger [ , ] which required two jets reconstructed in the calorimeter. the hadronic system (including the decay electron) was reconstructed from energy-flow objects (efos) [ ] which combine the information from calorimetry and tracking, cor- rected for energy loss in inactive material. each efo was assigned a reconstructed four- momentum qi = (pix,p i y ,p i z,e i), assuming the pion mass. jets were reconstructed from efos using the kt algorithm [ ] in the longitudinally invariant mode with the massive recombination scheme [ ] in which qjet = ∑ i qi and the sum runs over all efos. the transverse energy of the jet was defined as e jet t = e jet · pjett /pjet, where ejet, pjet and p jet t are the energy, momentum and transverse momentum of the jet, respectively. the trans- verse energy, e jet t , is therefore always larger than the transverse momentum, p jet t , used in a previous publication [ ]. dijet events were selected as follows: • at least two jets with ejett > ( ) gev for the highest (second highest) energetic jet and pseudorapidity of both jets |ηjet| < . ; • the z coordinate of the reconstructed primary vertex within |zvtx| < cm; • . < yjb < . , where yjb = (e − pz )/( ee) is the jacquet-blondel estimator [ ] for the inelasticity, y, and e − pz = ∑ i ei − piz , where the sum runs over all efos; • no scattered-electron candidate found in the calorimeter with energy e′e > gev and ye < . , with ye = − e ′ e ee ( − cos θ′e), where θ′e is the polar angle of the outgoing electron. these cuts suppress background from high-q events and from non-ep interactions, and correspond to an effective cut of q < gev . identification of electrons from semileptonic decays electron candidates were selected among the efos by requiring tracks fitted to the pri- mary vertex and having a transverse momentum, pet , of at least . gev in the pseu- dorapidity range |ηe| < . . only the efos consisting of a track matched to a single calorimetric cluster were used. to reduce the hadronic background and improve the overall description, at least % of the efo energy had to be deposited in the electro- magnetic part of the calorimeter. electron candidates were required to have a track with ntrunc > to ensure a reliable de/dx measurement. an additional preselection cut of de/dx > . mip was applied to reduce the background. candidates in the angular re- gion corresponding to the gaps between fcal and bcal as well as between rcal and bcal were removed using a cut on the efo position [ ]. electrons from photon conversions were tagged and rejected based on the distance of closest approach of a pair of oppositely charged tracks to each other in the plane perpen- dicular to the beam axis and on their invariant mass [ ]. untagged conversion background and electrons from dalitz decays were estimated from monte carlo studies. the electron candidate was required to be associated to a jet using the following proce- dure: • the jet had to have ejett > gev and |ηjet| < . ; • the distance ∆r = √ (ηjet − ηe) + (φjet − φe) < . ; • in case of more than one candidate jet, the jet closest in ∆r was chosen. for the identification of electrons from semileptonic heavy-quark decays, variables for particle identification were combined with event-based information characteristic of heavy- quark production. for a given hypothesis of particle, i, and source j, the likelihood, lij , is given by lij = ∏ l pij (dl) , where pij (dl) is the probability to observe particle i from source j with value dl of a discriminant variable. the particle hypotheses i ∈ {e,µ,π,k,p} and sources, j, for electrons from semileptonic beauty, charm decays and background, j ∈ {b,c, bkg}, were considered. for the likelihood ratio test, the test function, tij was defined as tij = αiα ′ jlij ∑ m,n αmα′nlmn . the αi, α ′ j denote the prior probabilities taken from monte carlo. in the sum, m,n run over all particle types and sources defined above. in the following, t is always taken to be the likelihood ratio for an electron originating from a semileptonic b-quark decay: t ≡ te,b, unless otherwise stated. the following five discriminant variables were combined in the likelihood test: • de/dx, the average energy loss per unit length of the track in the ctd; • eemc/ecal, the fraction of the efo energy taken from the calorimeter information, ecal, which is deposited in the electromagnetic part, eemc; • ecal/ptrack: the efo energy divided by the track momentum. in order to distinguish between electrons from semileptonic b-quark and c-quark decays and other electron candidates, the following additional observables were used: • prel⊥ , the transverse-momentum component of the electron candidate relative to the direction of the associated jet defined as prel⊥ = |~pjet × ~pe| |~pjet| , where ~pe is the momentum of the electron candidate. the variable p rel ⊥ can be used to discriminate between electrons from semileptonic b-quark decays and from other sources, because its distribution depends on the mass of the decaying particle. it is not possible to distinguish charm from light-flavour decays with this variable; • ∆φ, the difference of azimuthal angles of the electron candidate and the missing trans- verse momentum vector defined as ∆φ = |φ(~pe) − φ(~ pt )| , where ~ pt is the negative vector sum of the efo momentum transverse to the beam axis, ~ pt = − ( ∑ i pix, ∑ i piy ) , and the sum runs over all efos. the vector ~ pt is used as an estimator of the di- rection of the neutrino from the semileptonic decay. the variable ∆φ can be used to discriminate semileptonic decays of b quarks and c quarks from other sources. the shapes of the charm- and light-quark prel⊥ distributions in the monte carlo were corrected [ ] using a dedicated background sample in the data. the value of the correction increased with prel⊥ and was % at p rel ⊥ = . gev, where the purity of the b contribution is highest. for the ∆φ distribution a correction was determined in a similar way, but in this case the maximal correction was only of the order of %. in fig. the distributions of the five input variables used in the likelihood are shown for electrons from b-quark and c-quark decays and for electron candidates from other sources. a clear difference in shape between signal and background can be seen. signal extraction the electron candidates in the monte carlo samples were classified as originating from beauty, charm or background. the beauty sample also contains the cascade decays b → c → e, but not b → τ → e and b → j/ψ → e+e− that have been included in the background sample. test functions (see section ) were calculated separately for the three samples. the fractions of the three samples in the data, fdatae,b , f data e,c , f data bkg , were obtained from a three-component maximum-likelihood fit [ ] to the t distributions. the constraint fdatae,b + f data e,c + f data bkg = was imposed in the fit. the fit range of the test function was restricted to − ln t < to remove the region dominated by background and where the test function falls rapidly. the χ for the fit is χ /ndf = / and the b-quark and c-quark measurements have a correlation coefficient of − . . the result of the fit is shown in fig. and corresponds to a scaling of the cross section predicted by the beauty monte carlo by a factor of . ± . and the charm monte carlo by a factor of . ± . . these factors are applied to figs. – and denoted as “pythia (scaled)”. a fit over the whole t range gave consistent cross sections and was used as a cross-check. the distributions of the five variables that entered the likelihood are shown in fig. . the description of all variables is reasonable. these distributions are dominated by the background contribution. in order to select a beauty-enriched sample, a cut of − ln t < was applied. the resulting distributions are shown in fig. . a likelihood for semileptonic charm can also be constructed, te,c. the distributions of the likelihood for a sample satisfying − ln te,c < . are shown in fig. . good agreement is observed in both cases. to demonstrate the quality of the data description by the monte carlo, the distributions of e jet t and η jet of the jet associated with the electron and of the pet of the electron candidates are compared in fig. a)–c). in fig. d)–i) the same distributions are compared for the beauty- and charm enriched-samples. some differences are observed in the jet variables, mainly in the region dominated by background. the agreement significantly improves for samples enriched in beauty and charm signal. cross section determination the cross sections have been measured in the kinematic range q < gev , . < y < . , with at least two jets with e jet t > ( ) gev, |ηjet| < . and an electron from a semileptonic decay with pet > . gev in the range |ηe| < . . the differential beauty cross section for a variable, v, was determined separately for each bin, k, from the relative fractions in the data obtained from the fit and the acceptance correction, abvk , calculated using the monte carlo, dσb dvk = ndata · fdatae,b (vk) abvk · l · ∆vk , where ndata is the number of electron candidates found in the data, l is the integrated luminosity and ∆vk is the bin width. in order to determine the acceptance, the jet-finding algorithm was applied to the mc events after the detector simulation and at hadron level. the acceptance is defined as a = n obs e nhade , where nobse is the number of electrons from semileptonic decays reconstructed in the monte carlo satisfying the selection criteria detailed in sections and , and nhade is the number of electrons from semileptonic decays produced in the signal process that satisfy the kinematic requirements using the monte carlo information at the generator level. at hadron level, the kt algorithm was applied to all final-state particles with a lifetime of τ > . ns and the electron was associated to its parent jet using the generator information. all cross sections were measured separately for the two centre-of-mass energies √ s = and gev. additionally, the cross sections were calculated with the whole data set and were corrected to √ s = gev. the correction factor of ≈ % was determined with lo as well as nlo calculations. the charm cross sections were measured using the same procedure. systematic uncertainties the systematic uncertainties were calculated by varying the analysis procedure and then redoing the fit to the likelihood distributions. the following sources were the main con- tributors to the systematic uncertainty (the first value in parentheses is the uncertainty for beauty, while the second is that for charm): • the systematic uncertainty on the description of the de/dx information was estimated by looking at the differences between the various calibration and validation samples. variations in the mean, width and shape of the distributions were evaluated and used as a measure of the uncertainty [ ]. the resulting uncertainty was found to be (+ − % / + − %); • the changes in the correction to the prel⊥ distribution in various kinematic ranges were taken as a measure of its uncertainty. for prel⊥ = . gev the variation was % of the correction. the changes led to a systematic uncertainty of (+ − % / + − %). in addition, the correction to the charm distribution was varied from zero to that of the background sample. this led to an uncertainty of (+ − % / + − %); • a shift of the cal energy scale in the monte carlo simulation by ± % (± % / ± %); • reweighting of the direct and non-direct contributions in the monte carlo to provide a better description of the data (+ % / + %); • the estimated residual number of electrons left in the sample from photon conversions as well as from dalitz decays were varied by % and % respectively [ ]. this led to systematic uncertainties of (± % / ∓ %) due to photon conversions and (± % / ∓ %) due to dalitz decays. these systematic uncertainties were added in quadrature separately for the negative and the positive variations to determine the overall systematic uncertainty of + − % for the beauty and + − % for the charm cross sections. since no significant dependence of the systematic uncertainties on the kinematic variables was observed, the same uncertainty was applied to each data point. a % overall normalisation uncertainty associated with the luminosity measurement was included. a series of further checks were made. the cut on the transverse momentum of the electron candidate was varied by ± %, which is the momentum uncertainty for a track with pt = . gev. the ∆φ correction was varied within its uncertainty. the cut on ∆r to associate the decay electron with a jet was varied between . and . . the effect of the gaps between fcal and bcal as well as between rcal and bcal was investigated by varying the cut on the efo position. various tests of the signal-extraction method were made: e.g. using the likelihood without the eemc/ecal or ecal/ptrack variables; applying the fit on a signal-enriched sample by making tighter cuts on the input variables and varying the fit range. the prior probabilities were recalculated after the fit and used as the input for a second fit iteration. separate fits were made for electron and positron candidates for each of the lepton beam particles (e− and e+) separately as well as for the combined sample. all variations were found to be consistent with the expected fluctuations due to statistics; therefore they have not been added to the systematic uncertainty. theoretical predictions and uncertainties qcd predictions at nlo, based on the fmnr programme [ ], are compared to the data. the programme separately generates processes containing point-like and hadron- like photon contributions, which have to be combined to obtain the total cross section. the bb and the cc production cross sections were calculated separately. the parton distribution functions were taken from cteq m [ ] for the proton and grv-g ho [ ] for the photon. the heavy-quark masses (pole masses) were set to mb = . gev and mc = . gev. the strong coupling constant, Λ ( ) qcd, was set to . gev. the renormalisation, µr, and factorisation, µf , scales were chosen to be equal and set to µr = µf = √ p̂ t + m b(c) , where p̂t is the average transverse momentum of the heavy quarks. the peterson fragmentation function [ ], with ǫb = . and ǫc = . [ ], was used to produce beauty and charm hadrons from the heavy quarks. for the bb and cc cross sections, the decays into electrons were simulated using decay spectra from pythia. for beauty, both the contributions from prompt and from cascade decays, excluding b → τ → e and b → j/ψ → e+e−, are taken into account in the effective branching fraction. the values were set to . for the bb and to . for the cc cross sections [ ]. for the systematic uncertainty on the theoretical prediction, the masses and scales were varied simultaneously to maximise the change in the cross section using the values: mb = . , . gev, mc = . , . gev and µr = µf = √ p̂ t + m b(c) , √ p̂ t + m b(c) . the effects of different parton density functions as well as variations of ǫb within the un- certainty of . had a small effect on the cross-section predictions and were neglected. the parameter ǫc was varied between . and . and the contribution was added in quadrature to the systematic uncertainty. the uncertainty on the electron decay spectra, evaluated from comparisons to experimental measurements [ , ] and to a simple free- quark decay model, was found to be small compared to the total theoretical uncertainty and was neglected. the uncertainty on the nlo qcd predictions for the total cross section are + % and − % for beauty and + % and − % for charm. the nlo qcd predictions for parton-level jets, reconstructed by applying the kt al- gorithm to the outgoing partons, were corrected for hadronisation effects. a bin-by-bin procedure was used according to dσ = dσnlo · chad, where dσnlo is the cross section for partons in the final state of the nlo calculation. the hadronisation correction factor, chad, was defined as the ratio of the dijet cross sections, extracted from the pythia monte carlo, after and before the hadronisation process, chad = dσhadronsmc /dσ partons mc . the hadronic corrections were generally small and are given in tables – . no uncertainty was assigned to the correction. results the visible ep cross sections (quoted at hadron level) for b-quark and c-quark production and the subsequent semileptonic decay to an electron with pet > . gev in the range |ηe| < . in photoproduction events with q < gev and . < y < . and at least two jets with et > ( ) gev, |η| < . were determined separately for √ s = gev and √ s = gev. the measurements are given in table and are shown in fig. . the cross sections at the two different centre-of-mass energies are consistent with each other; combining the results leads to a reduced statistical uncertainty. for the complete data set ( – ) the cross sections evaluated at √ s = gev are σvisb = ( ± (stat.)+ − (syst.) ) pb, σvisc = ( ± (stat.)+ − (syst.) ) pb. the visible b-quark cross section was also determined in the kinematic region of a previous zeus analysis using muons [ ] and is in good agreement. the nlo qcd predictions of fmnr (see table ) are compared to the data in fig. . good agreement is observed. also shown in fig. are expectations of the pythia monte carlo. the combined b(b) cross section is a factor . higher while the c(c) cross section is a factor of . higher than the pythia prediction (see section ). these factors are used to scale the pythia predictions in the following figures. differential cross sections as a function of pet and ηe, x obs γ , e jet t and η jet are shown in figs. , and , respectively. the variable xobsγ is defined as xobsγ = ∑ i= , (e jet i − pjet iz ) e − pz , where the sum is over the two highest-energy jets, and corresponds at leading order to the fraction of the exchanged-photon momentum in the hard scattering process. the figures also show the nlo qcd and the scaled pythia predictions. the cross-section values are given in tables – . both the predictions from the nlo qcd calculations as well as the scaled pythia cross sections describe the data well. the differential cross sections as a function of the transverse energy of the jet associated with the electron from the semileptonic decay, e e jet t , were also determined. these cross sections are shown in fig. and given in table . the good agreement with the nlo qcd prediction allows the cross section as a function of pbt to be extracted [ ]. the resulting cross section is shown in fig. and is also compared with previous zeus measurements [ , , ]. the results presented here overlap in pbt with these previous measurements and have comparable or smaller uncertainties, giving a consistent picture of b-quark production in ep collisions in the photoproduction regime. conclusions beauty and charm production have been measured in dijet photoproduction using semilep- tonic decays into electrons. the results were obtained by simultaneously extracting the b- and c-quark cross sections using a likelihood ratio optimised for b-quark production. one of the most important variables in the likelihood was the de/dx measurement in the central tracking detector. the results were compared to both nlo qcd calculations as well as predictions from monte carlo models. the nlo qcd predictions are consistent with the data. the monte carlo models describe well the shape of the differential distributions in the data. the results on b-quark production are also in agreement with a previous less precise zeus measurement using semileptonic decays into electrons. within the momentum range covered by previous zeus measurements using decays into muons, good agreement is found. the cross section as a function of the transverse momentum of the b quarks has been measured over a wide range. the measurements agree well with the previous values, giving a consistent picture of b-quark production in ep collisions in the photoproduction regime, and are well reproduced by the nlo qcd calculations. acknowledgements we thank the desy directorate for their strong support and encouragement. the re- markable achievements of the hera machine group were essential for the successful completion of this work. the design, construction and installation of the zeus detector have been made possible by the effort of many people who are not listed as authors. references [ ] m. glück, e. reya and a. vogt, phys. rev. d , ( ). [ ] s. frixione, p. nason and g. ridolfi, nucl. phys. b ( ); s. frixione et al., phys. lett. b , ( ). [ ] zeus collab., s. chekanov et al., eur. phys. j. c , ( ). [ ] zeus collab., s. chekanov et al., phys. lett. b , ( ). [ ] zeus collab., s. chekanov et al., phys. rev. d , ( ). erratum-ibid d , ( ). [ ] zeus collab., j. breitweg et al., eur. phys. j. c , ( ). [ ] zeus collab., s. chekanov et al., phys. lett. b , ( ). [ ] zeus collab., s. chekanov et al., preprint desy- - (arxiv: . v [hep-ex]), . accepted by jhep. [ ] zeus collab., s. chekanov et al., nucl. phys. b , ( ). [ ] zeus collab., s. chekanov et al., eur. phys. j. c , ( ). [ ] zeus collab., s. chekanov et al., phys. rev. d , ( ). [ ] zeus collab., s. chekanov et al., phys. lett. b , ( ). [ ] zeus collab., j. breitweg et al., eur. phys. j. c , ( ). [ ] zeus collab., j. breitweg et al., phys. lett. b , ( ). [ ] zeus collab., j. breitweg et al., eur. phys. j. c , ( ). [ ] zeus collab., j. breitweg et al., phys. lett. b , ( ). 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[ ] n. harnew et al., nucl. instr. and meth. a , ( ); b. foster et al., nucl. phys. proc. suppl. b , ( ); b. foster et al., nucl. instr. and meth. a , ( ). [ ] m. derrick et al., nucl. instr. and meth. a , ( ); a. andresen et al., nucl. instr. and meth. a , ( ); a. caldwell et al., nucl. instr. and meth. a , ( ); a. bernstein et al., nucl. instr. and meth. a , ( ). [ ] j. andruszków et al., preprint desy- - , desy, ; zeus collab., m. derrick et al., z. phys. c , ( ); j. andruszków et al., acta phys. pol. b , ( ). [ ] d. bartsch, energy-loss measurement with the zeus central tracking detector. ph.d. thesis, universität bonn, bonn, germany, report bonn-ir- - , , available on http://www-zeus.physik.uni-bonn.de/german/phd.html. [ ] w.w.m. allison and j.h. cobb, annual review in nuclear & particle physics , ( ). [ ] t. sjöstrand et al., comp. phys. comm. , ( ); e. norrbin and t. sjöstrand, eur. phys. j. c , ( ); t. sjöstrand, l. lönnblad, and s. mrenna, preprint hep-ph/ , . [ ] o.m. kind, production of heavy flavours with associated jets at hera. ph.d. thesis, universität bonn, bonn, germany, report bonn-ir- - , , available on http://www-zeus.physik.uni-bonn.de/german/phd.html. [ ] h.l. lai et al., phys. rev. d , ( ). [ ] m. glück, e. reya and a. vogt, phys. rev. d , ( ). [ ] r. brun et al., geant , technical report cern-dd/ee/ - , cern, . [ ] r. zimmermann, kalibrierung und charakterisierung der de/dx-information der zentralen driftkammer bei zeus. diploma thesis, universität bonn, bonn, germany, report bonn-ib- - , , available on http://www-zeus.physik.uni-bonn.de/german/diploma.html. [ ] w.h. smith, k. tokushuku and l.w. wiggers, proc. computing in high-energy physics (chep), annecy, france, c. verkerk and w. wojcik (eds.), p. . cern, geneva, switzerland ( ). also in preprint desy - b. [ ] zeus collab., j. breitweg et al., eur. phys. j. c , ( ); g.m. briskin, diffractive dissociation in ep deep inelastic scattering. ph.d. thesis, tel aviv university, report desy-thesis - , . [ ] s.d. ellis and d.e. soper, phys. rev. d , ( ). [ ] s. catani et al., nucl. phys. b , ( ). [ ] f. jacquet and a. blondel, proceedings of the study for an ep facility for europe, u. amaldi (ed.), p. . hamburg, germany ( ). also in preprint desy / . [ ] m. jüngst, elektronidentifikation mit dem zeus-detektor und bestimmung des beauty-produktionsquerschnitts. diploma thesis, universität bonn, bonn, germany, report bonn-ib- - , , available on http://www-zeus.physik.uni-bonn.de/german/diploma.html. [ ] r. barlow and c. beeston, comp. phys. comm. , ( ). [ ] w. verkerke, measurement of charm production deep inelastic scattering. ph.d. thesis, university of amsterdam, . unpublished. [ ] s. frixione et al., nucl. phys. b , ( ); s. frixione et al., adv. ser. direct. high energy phys. , ( ). [ ] cteq collab., h.l. lai et al., eur. phys. j. c , ( ). [ ] c. peterson et al., phys. rev. d , ( ). [ ] p. nason and c. oleari, nucl. phys. b , ( ). [ ] particle data group, w.-m. yao et al., j. phys g , ( ). [ ] belle collaboration, k. abe et al., phys. lett. b , ( ); babar collaboration, b. auert et al., phys. rev. d , ( ). [ ] cleo collaboration, n.e. adam et al., phys. rev. lett. , ( ). σvisb σ nlo b c had b σ vis c σ nlo c c had c (pb) (pb) (pb) (pb) — ± + − +− . ± + − +− . — ± + − +− . ± + − +− . — ± + − +− . ± + − +− . table : total cross sections for electrons from b or c quarks in photoproduction events, q < gev and . < y < . , with at least two jets with e jet t > ( ) gev , |ηjet| < . and the subsequent semileptonic decay to an electron with pet > . gev and |ηe| < . . the values are given separately for √ s = gev ( — ) and√ s = gev ( — ) as well as for the complete data set ( — ) extrapolated to √ s = gev . the first error is statistical and the second is systematic. in addition, the nlo qcd prediction and its uncertainty is given, after applying the appropriate hadronisation correction (chadb , c had c ). pet dσb/dp e t dσ nlo b /dp e t c had b dσc/dp e t dσ nlo c /dp e t c had c ( gev) (pb/ gev) (pb/ gev) (pb/ gev) (pb/ gev) . : . . ± . + . − . +− . ± + − +− . . : . . ± . + . − . . +− . . . . ± . + . − . +− . . : . . ± . + . − . . +− . . . . ± . + . − . +− . . : . . ± . + . − . . +− . . . . ± . + . − . . +− . . . ηe dσb/dη e dσnlob /dη e chadb dσc/dη e dσnloc /dη e chadc (pb) (pb) (pb) (pb) - . : - . . ± . + . − . . +− . . . ± + − +− . - . : . . ± . + . − . . +− . . . ± + − +− . . : . . ± . + . − . . +− . . . ± + − +− . . : . . ± . + . − . . +− . . . ± + − +− . table : differential electron cross sections as a function of pet and η e for the complete data set. for further details see the caption of table . xobsγ dσb/dx obs γ dσ nlo b /dx obs γ c had b dσc/dx obs γ dσ nlo c /dx obs γ c had c (pb) (pb) (pb) (pb) . : . ± + − +− . ± + − +− . . : . ± + − +− . ± + − +− . . : . ± + − +− . ± + − +− . table : differential cross sections as a function of xobsγ for the complete data set. for further details see the caption of table . e jet t dσb/e jet t dσ nlo b /e jet t c had b dσc/e jet t dσ nlo c /e jet t c had c ( gev) (pb/ gev) (pb/ gev) (pb/ gev) (pb/ gev) : . ± . + . − . . +− . . . . ± . + . − . +− . : . ± . + . − . . +− . . . . ± . + . − . +− . : . ± . + . − . . +− . . . . ± . + . − . . +− . . . : . ± . + . − . . +− . . . . ± . + . − . . +− . . . ηjet dσb/dη jet dσnlob /dη jet chadb dσc/dη jet dσnloc /dη jet chadc (pb) (pb) (pb) (pb) - . : - . . ± . + . − . . +− . . . ± + − +− . - . : . . ± . + . − . . +− . . . ± + − +− . . : . . ± . + . − . . +− . . . ± + − +− . . : . . ± . + . − . . +− . . . ± + − +− . table : differential cross sections for the most energetic jet as a function of e jet t and ηjet for the complete data set. for further details see the caption of table . e e jet t dσb/e e jet t dσ nlo b /e e jet t c had b dσc/e e jet t dσ nlo c /e e jet t c had c ( gev) (pb/ gev) (pb/ gev) (pb/ gev) (pb/ gev) : . ± . + . − . . +− . . . . ± . + . − . +− . : . ± . + . − . . +− . . . . ± . + . − . . +− . . . : . ± . + . − . . +− . . . . ± . + . − . . +− . . . table : differential cross sections of e e jet t for the jet associated to the electron from beauty or charm decays for the complete data set. for further details see the caption of table . . . . . . . . . βγ (m ip ) e π k p µ zeus figure : the mean de/dx measured in the ctd, 〈de/dx〉, as a function of βγ for different samples of identified particles as denoted in the figure. the curve shows a physically motivated parametrisation of the 〈de/dx〉 dependence on βγ. pred ) / de/dx pred - de/dx obs (de/dx - - . . t ra c k s data = ) trunc ( n zeus pred ) / de/dx pred - de/dx obs (de/dx - - . . t ra c k s figure : distribution of the relative difference between the observed (de/dxobs) and predicted (de/dxpred) specific energy loss for the track sample with ntrunc = . the inset shows the same distribution with a logarithmic ordinate scale. de/dx (mip) . . . a rb it ra ry u n it s - - - - de/dx (mip) . . . a rb it ra ry u n it s - - - - (a) (gev)relp . . . . a rb it ra ry u n it s - - - . . . . a rb it ra ry u n it s - - - (d) cal /eemce . . . . . a rb it ra ry u n it s - - - - cal /eemce . . . . . a rb it ra ry u n it s - - - - (b) (rad)φ∆ . . . a rb it ra ry u n it s - (rad)φ∆ . . . a rb it ra ry u n it s - (e) track /p cal e . . . . . . a rb it ra ry u n it s - - - - track /p cal e . . . . . . a rb it ra ry u n it s - - - - (c) e x→b e x →c bkg figure : normalised distributions of the five input variables used in the likelihood for the electron candidates extracted from the monte carlo, without applying the cuts on de/dx and eemc/ecal. the solid line shows the distribution for electrons from semileptonic b-quark decays, the dashed line for c-quark decays and the dotted line the background (bkg). - ln t - c a n d n zeus pythia (scaled) e x→b e x→c bkg - zeus pb - ln t - c a n d n figure : the distribution of the likelihood ratio for electron candidates, ncand, in data compared to the monte carlo expectation after the fit described in the text. the arrow indicates the region included in the fit (− ln t < ). the shaded areas show the fitted contributions from b quarks, c quarks and background as denoted in the figure. de/dx (mip) . . . c a n d n de/dx (mip) . . . c a n d n (a) (gev)relp . . . . c a n d n . . . . c a n d n (d) cal /eemce . . . . . c a n d n cal /eemce . . . . . c a n d n (b) (rad)φ∆ . . . c a n d n (rad)φ∆ . . . c a n d n (e) track /p cal e . . . . . . c a n d n track /p cal e . . . . . . c a n d n (c) pythia (scaled) e x→b e x →c bkg < e,b- ln t - zeus pb zeus figure : distributions of the five input variables of the likelihood for the electron candidates used in the fit (− ln t < ). all cuts have been applied except de/dx > . in a) and eemc/ecal > . in b) (the cuts are indicated in the figure). the shaded areas show the contributions from b quarks, c quarks and background as denoted in the figure, after applying the scale factors from the fit. zeus de/dx (mip) . . . c a n d n de/dx (mip) . . . c a n d n (a) (gev)relp . . . . c a n d n . . . . c a n d n (d) cal /eemce . . . . . c a n d n cal /eemce . . . . . c a n d n (b) (rad)φ∆ . . . c a n d n (rad)φ∆ . . . c a n d n (e) track /p cal e . . . . . . c a n d n track /p cal e . . . . . . c a n d n (c) pythia (scaled) e x→b e x →c bkg < e,b- ln t - zeus pb figure : distributions of the five input variables of the likelihood for a beauty enriched sample (candidates with − ln t < ). in these plots the ordinate is shown on a linear scale. other details as in the caption of fig. . zeus de/dx (mip) . . . c a n d n de/dx (mip) . . . c a n d n (a) (gev)relp . . . . c a n d n . . . . c a n d n (d) cal /eemce . . . . . c a n d n cal /eemce . . . . . c a n d n (b) (rad)φ∆ . . . c a n d n (rad)φ∆ . . . c a n d n (e) track /p cal e . . . . . . c a n d n track /p cal e . . . . . . c a n d n (c) pythia (scaled) e x→b e x →c bkg < . e,c- ln t - zeus pb figure : distributions of the five input variables of the likelihood for a charm enriched sample (candidates with − ln te,c < . ). in these plots the ordinate is shown on a linear scale. other details as in the caption of fig. . zeus (gev) e jet te / g e v c a n d n / g e v c a n d n (a) (gev) e jet te / g e v c a n d n / g e v c a n d n (d) (gev) e jet te / g e v c a n d n / g e v c a n d n (g) e jetη - - . - - . . . c a n d n e jetη - - . - - . . . c a n d n (b) e jetη - - . - - . . . c a n d n e jetη - - . - - . . . c a n d n (e) e jetη - - . - - . . . c a n d n e jetη - - . - - . . . c a n d n (h) (gev)e t p / g e v c a n d n (gev)e t p / g e v c a n d n (c) (gev)e t p / g e v c a n d n (gev)e t p / g e v c a n d n (f) (gev)e t p / g e v c a n d n pythia (scaled) e x→b e x →c bkg - zeus pb (gev)e t p / g e v c a n d n (i) < e,b- ln t < e,b- ln t < . e,c- ln t figure : distributions of e e jet t and η e jet t of the jet associated with the electron, and pet of the electron candidate. figures a)-c) contain all electron candidates satisfying − ln te,b < ; d)-f) and g)-i) show the same distributions for the beauty (− ln te,b < ) and charm (− ln te,c < . ) enriched samples, respectively. other details as in the caption of fig. . (gev)s ( p b ) v is σ zeus − zeus pb e x→b e x→c nlo qcd pythia figure : total cross sections for electrons from b and c quarks in photoproduction events, q < gev and . < y < . , with at least two jets with et > ( ) gev , |η| < . and the subsequent semileptonic decay to an electron with pt > . gev and |η| < . . the measurements are shown as points. the inner error bar shows the statistical uncertainty and the outer error bar shows the statistical and sys- tematic uncertainties added in quadrature. the solid line shows the nlo qcd prediction after hadronisation corrections, with the theoretical uncertainties indi- cated by the band; the dashed line shows the prediction from pythia. zeus (gev)e t p ( p b /g e v ) e t /d p b σ d (gev)e t p ( p b /g e v ) e t /d p b σ d (a) eη - . - - . . . ( p b ) e η /d b σ d - zeus pb e x →b nlo qcd pythia x . eη - . - - . . . ( p b ) e η /d b σ d (b) (gev)e t p ( p b /g e v ) e t /d p c σ d (gev)e t p ( p b /g e v ) e t /d p c σ d (c) eη - . - - . . . ( p b ) e η /d c σ d - zeus pb e x →c nlo qcd pythia x . eη - . - - . . . ( p b ) e η /d c σ d (d) figure : differential cross sections as a function of a), c) the transverse momentum and b), d) the pseudorapidity of the electrons. plots a) and b) are for b- quark production while c) and d) are for c-quark production. the measurements are shown as points. the inner error bar shows the statistical uncertainty and the outer error bar shows the statistical and systematic uncertainties added in quadrature. the solid line shows the nlo qcd prediction after hadronisation corrections, with the theoretical uncertainties indicated by the band; the dashed line shows the scaled prediction from pythia. zeus obs γx . . . . ( p b ) o b s γ /d x b σ d obs γx . . . . ( p b ) o b s γ /d x b σ d - zeus pb e x →b nlo qcd pythia x . (a) obs γx . . . . ( p b ) o b s γ /d x c σ d obs γx . . . . ( p b ) o b s γ /d x c σ d - zeus pb e x →c nlo qcd pythia x . (b) figure : differential cross sections as a function of xobsγ . a) shows the dis- tribution for electrons from b-quark production while b) shows c-quark production. other details as in the caption of fig. . zeus (gev) jet te ( p b /g e v ) je t t /d e b σ d (gev) jet te ( p b /g e v ) je t t /d e b σ d (a) jet η - ( p b ) je t η /d b σ d - zeus pb e x →b nlo qcd pythia x . jet η - ( p b ) je t η /d b σ d (b) (gev) jet te ( p b /g e v ) je t t /d e c σ d (gev) jet te ( p b /g e v ) je t t /d e c σ d (c) jet η - ( p b ) je t η /d c σ d - zeus pb e x →c nlo qcd pythia x . jet η - ( p b ) je t η /d c σ d (d) figure : differential cross sections as a function of a), c) the transverse energy and b), d) the pseudorapidity of the highest-energy jet. plots a) & b) show the distributions for electrons from b-quark production while plots c) & d) show those for c-quark production. other details as in the caption of fig. . zeus (gev) e jet te ( p b /g e v ) je t t /d e b σ d - zeus pb e x →b nlo qcd pythia x . (a) (gev) e jet te ( p b /g e v ) e j e t t /d e c σ d - - zeus pb e x →c nlo qcd pythia x . (b) figure : differential cross sections for a) b-quark and b) c-quark production as a function of the transverse energy of the jet associated to the electron. other details as in the caption of fig. . (gev)b t p ( p b /g e v ) b t /d p σ d e→ b - zeus pb µ d* → b zeus - µ → b zeus - e→ b zeus - nlo qcd | < b η| ebx)→ (ep b t /dpσd < gev q . < y < . zeus figure : differential cross section for b-quark production as a function of transverse momentum, pbt , compared to the results of previous zeus measurements as indicated in the figure. the measurements are shown as points. the inner error bar shows the statistical uncertainty and the outer error bar shows the statistical and systematic uncertainties added in quadrature. the solid line shows the nlo qcd prediction from the fmnr program with the theoretical uncertainty shown as the shaded band. 书籍 .indb issn - [print] issn - [online] www.cscanada.net www.cscanada.org canadian social science vol. , no. , , pp. - doi: . /j.css. . copyright © canadian academy of oriental and occidental culture impact of beauty fashion on contemporary chinese youth li changsong[a],* [a]lecturer, school of politics and public management, southwest university, china. research field: youth education theory and practice. *corresponding author. supported by the western project of national found of social science—research on basic experience of chinese communist party in terms of the diversified social thoughts since the reform and opening up (no. xks ). received july ; accepted october abstract beauty fashion is the product as well as the reflection of the new age. its emergence and prosperity, on the one hand, cater to the contemporary chinese youth’s psychological seeking for beauty characterized by seeking for novelty, change and fashion; on the other hand, they have exerted immense impact on the young’s value orientation, aesthetic sentiment, consumer attitude, character and lifestyle due to their own limitations and their incomplete understanding of beauty and fashion. key words: beauty fashion; youth; impact l i c h a n g s o n g ( ) . i m p a c t o f b e a u t y f a s h i o n o n c o n t e m p o r a r y c h i n e s e yo u t h . c a n a d i a n s o c i a l s c i e n c e, ( ) , - . av a i l a b l e f r o m : h t t p : / / w w w . c s c a n a d a . n e t / i n d e x . p h p / c s s / a r t i c l e / v i e w / j . c s s . . doi: http://dx.doi.org/ . /j.css. . . introduction beauty fashion is a kind of group preference and trend revealed in the process in which people are seeking for beauty under the contemporary conditions with a similar social psychology and in a similar behavioral way. it is the product and reflection of contemporary socio-political, economic and cultural development, and also enjoys such features as novelty, diversity and time variability. youth, as a special group, has a lot of say in beauty seeking. the vast majority of them are passionate about innovative ideas and changes so that what is popular today may turn out to be obsolete next day. flourishing under the contemporary conditions, beauty fashion not only caters to chinese youth’s unique psychology for beauty and helps them realize the beauty-seeking dreams, but also exerts inconsiderable impact on them in terms of ideological and conceptual change and the transformation of way of life. to a large degree, they are the largest group affected by fashion beauty. . impact of fashion beauty on c o n t e m p o r a r y y o u t h va l u e orientation youth value orientation refers to their tendentious attitudes towards choices and pursuits. as a product of the current era of social development, beauty fashion has broadened the spiritual horizons of contemporary youth, enriched their spiritual life, and played a positive role in cultivating their ideas and concepts, which thus has made inconsiderable influence on their life value orientation. . enhancing the individuality of value pursuit the emergence of beauty fashion has impressed upon contemporary chinese youth’s pursuit of value, so that the values of contemporary chinese youth are gradually shifted to what are admired in the new era. the youth’s concerns about entertainment are highly concentrated on “serving their own interests”. the individualized values of advocating freedom, pursuing self-development, developing individuality, and creating new things gradually take root in the minds of contemporary chinese youth. in contrast, it appears that traditional values are fading away. the values held by contemporary youth are different from those of the previous generation copyright © canadian academy of oriental and occidental culture i m p a c t o f b e a u t y f a s h i o n o n contemporary chinese youth and are rarely affected by the traditional factors. in this sense, the young people have their own beauty preferences, aesthetic sentiment and consumer attitude. besides, they have their personality traits and lifestyles. i n d i v i d u a l f r e e d o m a n d s e l f - d e v e l o p m e n t h a v e become their life-pursuing goals. meanwhile, beauty fashion has created favorable conditions for youth’s development of personality in its unique way, which facilitates the production of individualized values such as desire for freedom, self-expression, and unwillingness to be restricted. under the influence of beauty fashion, contemporary chinese youth’s passion and pursuit of cosmetology way and cosmetic products which are revealing, pioneering, and sensational have given full expression of their individualized value pursuit. . vulgarize the values of some young people youth is a special life stage in which people chase popularity and fashion, care about their appearance, have a strong curiosity, and are keen to track and capture the subtle changes in the forefront of beauty. moreover, they are passionate in exchanging information of various beauty products and information on beauty. they often linger in diversified beauty places and institutions, and tend to take an initiative boldly. all these characteristics mentioned above are in line with the special development stage of life. however, some people are too indulged in it, pursuing individuality and gaudy and paying attention to dress-up, which in the long run too would have negative impact on choosing their mainstream life values, resulting in fading political ideals and weakening civic awareness. what is more, their lei feng spirit and patriotism would be given little attention so that the lofty ideals to serve the motherland would almost go bankrupt. in addition, the young are deficient in rational judgment in front of showy and fickle beauty fashion phenomena so that they are more likely to make value judgments based on some specific phenomena, which makes the mediocre things admired as trendy whereas profound and noble things considered outdated. beauty fashion, to some degree, gives rise to the phenomenon of vulgarization. and the youth’s irrational pursuit of weirdness and exaggeration breeds their spiritual needs for superficial and vulgar things. all these have hindered the improvement of values, making the values of some young people show the characteristics of vulgarization. . impact of beauty fashion on contemporary youth aesthetic sentiment the popularity of contemporary beauty fashion has had a profound impact on the aesthetic sentiment of contemporary chinese youth. they are no longer proud of mimicking the mainstream, and regard it as the overwhelming beauty; instead, they are willing to go along with it, seek novelty, difference, and exoticness to satisfy their own desires for beauty, and establish and express themselves through the pursuit and display of “personal charm” and “unique beauty”. . seeking novelty contemporary youth’s pursuit of novelty in aesthetic sentiment is essentially an indirect expression of their expectations for self-independence and desires for self- identity. contemporary youth always want to get rid of the old way of life, and create a new lifestyle. they are chasing fashion in order to keep up the pace without falling behind. so it often goes that before mastering a new thing, they would learn another brand-new one so as to meet their desires for novelty by constantly changing. the kind of desires for novelty has made their own beauty and dress-up also show novel characteristics. the advent of new beauty products and technologies will soon be the concern of young people, and the more novel beauty products are, the more likely they are to be chased by young people and thus become their “new favorites”. . valuing timeliness time variability is an important feature of beauty fashion, under the impact of which the aesthetic sentiment of contemporary chinese youth appears the characteristic of timeliness. we can find its expression in their pursuit of products and way of beauty fashion: the products and way of beauty fashion are produced and expanded all of a sudden but will soon fade away within a very limited time, or another new product and way of beauty fashion comes afore so that they turn their attention to the new one again. at present, no matter what kind of the popular beauty fashion is, it will cause the attention of young people. as far as the hairdressing is concerned, in the previous period the young people were chasing after dying hair. hence in a very short time, heads with hairs full-dyeing, half- dyeing, and highlighting are ubiquitous. the variety of colors on the heads could even overshadow the colors of the sky rainbow. with the passage of time, the attention of the young turned to straight hair. the falling and dynamic straight hair suddenly became the best choice for young people, and straight hair then was changed to a wide range of curly hair. coming all of a sudden and going out of blue is the most distinctive feature of timeliness of youth’s aesthetic sentiment. . mistakes in aesthetic ideas of some young people since the understanding of popular items for beauty fashion on the part of young people is limited, some of them may make mistakes in cultivating their aesthetic concept by blindly pursuing formatted beauty. therefore, “beauty” in the aesthetic ideas of these young people has been distorted and alienated, which could be copyright © canadian academy of oriental and occidental culture li changsong ( ). canadian social science, ( ), - represented by the following points: first, there are wrong interpretations of “beauty of individuality”. in fact, for the contemporary young “koreaphile” and “japanification”, the aim of what their beauty-pursuing is not for the benefit of the beauty itself, but to draw more attention when they are walking on the streets. what’s worse, they do not have a clear idea of whether their own image is beautiful or not. second, there is an excessive pursuit of “perfectness”. its aesthetic characteristics are demanding “exacting beauty”. for instance, if the joint of one finger is bit thick, then it is demanded to make it thinner; and if the foot bone is slightly bigger, then it is demanded to do an operation, so that the bone will be cut to be lanky. third, “weirdness” and “coolness” are worshipped as beautiful. the aesthetic standards held by these young people do not set the natural beauty high, but according to the standards, one with a piercing tongue, sharpened ears, elongated chin, navel plastic surgery and other quirky beauty is full of beauty. fourth, physical beauty is the only beauty. under the influence of the beauty fashion information such as “ideal body “, “perfect image”, and “one hundred perfect”, some young people one-sidedly focusing on mending and beautifying the physical beauty while ignoring the cultivation of the inner beauty of the soul. therefore, some erroneous aesthetic values are developed such as “physical beauty is more important than inner beauty” and “physical beauty is the key while inner beauty does not matter” and so on. . i m pa c t o n c o n t e m p o r a r y youth’s consumer attitude the young people are not only the main consumers of beauty fashion, but also the loyal consumers of various brands. the young and beauty fashion interact with each other. the contemporary youth, on the one hand, stimulate the development of beauty fashion; on the other hand, they are fully influenced by the consumer attitudes in the field of beauty. the main reflections are: . prominently valuing brand and high quality under the influence of beauty fashion, the contemporary chinese youth have showed largely high consumer desires for brands and high-quality products. they pay more attention to the reflection of identity and seeking high taste when turning to brands. when it comes to the brand awareness of such well-known brands as maybelline, avon, shiseido, yves saint laurent, clinique, elizabeth arden, etc., the contemporary youth population has arrived at about %. those overwhelming advertisements of modern beauty fashion and consumer demonstration of some celebrity model have constantly inculcated young people with some symbolic meaning of a product, a way of consumption as well as of a consumer attitude, thus continuously building symbol systems in the youth, so that young people could successfully register in the social community by gaining self and social recognition in the process of consumption. all these could reinforce the brand consumer awareness and high-quality consumer attitude in an intangible way. it’s easy to see them in a variety of beauty consumer sites. besides, they have enough knowledge about the beauty and continue to think about their money spending. they will spend money in consuming the beauty fashion products that they themselves believe are the most tasteful and with the best quality. of course, the upscale consumption on beauty is not what most young people could achieve, for the “brand consumption” is not only a matter of consumer attitudes, but also a matter of economic strength. . youth beauty consumerism making first appearance everything has a dual nature, and the beauty consumption on the part of the young people is not an exception. youth, as a special group, has created a special cultural environment. beauty fashion and its derivative beauty products, on the one hand, have catered to the needs of young consumers; on the other hand, due to the profitable commercial purposes, they have introduced an ideology of consumerism during the course of their popularity and spreading. youth beauty consumerism refers to the consumer attitudes and consumption pattern in the field of beauty under the influence of beauty fashion. it has lighted the passion of the young for beauty pursuit and has stimulated their desire to buy beauty products. today, there are a great number of young people who have such consumer attitudes as “following the fashion by consuming”, “one-step consumption”, and “excessive consumption”, and “being superior in consumption”. furthermore, today’s businessmen launched a variety of beauty products which are not placed in the counter in separation, but rather in the form of full set to publicize the products with all efforts. in this way, the consumption impulse of the young people is stimulated so that the logic of buying a beauty product is diverted to buy another beauty product, which inevitably develops a fixed consumption pattern aimed at young consumers. contemporary youth, due to the restriction of its own life experience and other deficiencies, lacks the ability to distinguish right and wrong. they make judgments and select beauty products merely out of personal preferences and impulse, which results in irrational consumption behaviors on the part of young people while they are passionately pursuing beauty products and cosmetology way. all these have made the youth’s beauty consumption concepts filled with a lot of blindness and in an unorganized nature, showing a consumerism tendency of “well-off morbidity” and “irrational consumption”. copyright © canadian academy of oriental and occidental culture i m p a c t o f b e a u t y f a s h i o n o n contemporary chinese youth . i m pa c t o f b e a u t y fa s h i o n o n c o n t e m p o r a r y y o u t h ’ s character the nature of the times is in line with the character of young people, and the character of young people reflects the trend of the times. the traits of youth’s character will surely be influenced and constraint by the society and cultural context in which they live. as a popular phenomenon in contemporary society, beauty fashion has made a vast majority of young people willing to express themselves and achieve their dreams, and in the process of pursuing beauty fashion, they have formed, changed and developed their own characters. . . expanding space for youth’s independent personality the intention of the youth for following fashion is to highlight the self, get admiration from the peers and envy from the opposite sex. since the young people have such psychology as independent curiosity, trying to be preeminent, and seeking success, they are finding independent freedom of personality that fits them in a constantly changing fashion and developing charisma in line with their own circumstances. in addition, they are trying to influence and impress others with such kind of independent freedom of personality and charisma so as to get recognition from others and the society. t h e i n d e p e n d e n c e o f y o u t h ’s p e r s o n a l i t y i s contradictory to the social influence. to put it more specific, the young not only could not make compromise to the social influence, and also have to maintain their personality and ensures that they do not swim with the times. social beauty fashion is in a constant change and development. in our modern society, beauty fashion could be seen everywhere and at any moment, under the impact of which the cognitive regulation, volitional efforts, emotional control, and self-reinforcement and other psychological conflicts have become very prominent. faced with the arrival of every beauty fashion, the young are inclined to chase, mimic, get obsessed in and unable to extricate themselves from it, which have caused blindness and uncertainty in youth character development and made the development course in a variable and repeated feature. however, we should also see that the arrival of beauty fashion has also created a new space for the formation and development of youth’s independent personality. on the one hand, the young people’s participation of beauty fashion has accelerated puberty socialization process, broken with their personality patterns in childhood, and accelerated the transition to adult character pattern; on the other hand, young people has given vent to their emotions in the pursuit of beauty fashion, enabling their personality recognized, meeting their “disparate demands”, and relatively completing the character pattern transformation. therefore, young people’s character formation and development has gradually “taken shape” in a series of unstable and constantly repeated process (zhang, , p. ). . opening up new field for youth’s self- confidence a r i s t o t l e o n c e s a i d , “ b e a u t y i s a m o r e p o w e r f u l recommendation than any letter of reference.” what kind of method can make you become self-confident? scientific studies show that the most simple and effective method is to make you become more beautiful. according to an authoritative survey, “ % of people think that dyeing hair can enhance self-confidence”, and “ % of women think that plump breasts could bring self-confidence to them”; what is more, some scholars also point out in their research, “keep one’s hairs clean is not only related to personal hygiene, but it directly affects people’s psychological characteristics including self-confidence, self-esteem, self-efficacy, and so forth (yang, ).” such slogans as “beauty can enhance self-confidence” and “where there is beauty, there is self-confidence” have become remarkable and popular among the contemporary young people. in our modern society where emphases are put on visual effects here and there, external beauty, on the one hand, has given enjoyment to people’s eyes; on the other hand, it continues to affect people’s judgment. if one’s external beauty is poor, the first impression given by him or her to others will be largely discounted. today, some companies are willing to pay big bucks, inviting beautiful women and handsome men in order to enhance the company’s overall image. besides, young men and women are increasingly focusing on each other’s appearance and temperament when choosing their soul mate. after all, natural beauty and not needing make-up belong only to a few people. the cheering thing is that the rise of beauty fashion is in a good position to provide homely young people with services such as “beauty mending”. hence, in order to enhance self- confidence and achieve success in job market and mate selection, a great number of young people are turning to cosmetic surgery. especially in today’s society where the “artificial beauty” gains momentum, the number is remarkably going up. the young are spending most of their income in in the packaging of their appearance and dressing up. . impact of beauty fashion on contemporary youth’s lifestyle there are a variety of forms of beauty fashion whose scale is expanding and contents become increasingly pervasive. all these have largely transformed young people’s ordinary way of life. greatly affected by the full impact of beauty fashion, the contemporary young people have a tireless desire and pursuit of a brand-new life. with more leisure time, they have updated the contents copyright © canadian academy of oriental and occidental culture li changsong ( ). canadian social science, ( ), - of life, increased the levels of their pursuits, and created numerous “excitements” one after another in life while seeking beauty, knowledge, and pleasure. . health is beauty with the advent of beauty fashion, young people have showed more concern about their health than ever before, and they are firmly convinced that there is no beauty without health. from the daily diet, outdoor sports, body-building to tobacco and alcohol quitting as well as overeating prohibitions, the contemporary youth is struggling to create a healthy environment for themselves, looking for a way of beauty that is fit to themselves. in the diet, they are paying more attention to “nutrition beauty”. proceeding from such aims as beautifying skin, hairdressing, slimming, losing weight, and improving eyesight which are conducive to their health and beauty, the young have formulated scientific “beauty nutrition menus” and set “health and beauty diet plan” tailored to themselves, treating their beauty with a healthy and nutritious diet. considering the importance of a regular healthy lifestyle, most young people have put an end to tobacco and alcohol abuse to protect their own health. at the meantime, such slogans as “life is movement”, “women will fall behind the times without exercises and “it is better to ask people to sweat than eat” have become the advertisements for present beauty fashion. a colourful series of sports like yoga, “parapara dance”, aerobics, equipment sports, and travel are becoming fashionable ways of exercises among the young people. all the things have revealed that the contemporary youth has realized doing a right amount of light sports could help speed up the body’s metabolism and cell replacement to beautify skin and lose weight; furthermore, it could reduce stress, relax themselves and enable them to maintain a best body condition , making health and beauty coexistent. . “slimming” exercises are popular the contemporary youth is quite concerned about the figure, for in our society filled with intense competition more and more young people are aware of the importance of good figure and temperament, which could leave a good impression on others, thus gaining more opportunities. therefore, as one of the most accepted item of beauty fashion among the young, “slimming” exercises have gained momentum. it advocates regarding “fatness” as the enemy and “slimness” as a friend, which meets the desires and needs of young people, thus becoming a hot pursuit of contemporary youth. “losing weight” popular in the past decades is obsolete, while “slimming” is penetrating into people’s minds. slimming methods such as beauty and slimming, slimming diet, slimming exercises, slimming methods and slimming thorough surgery are spreading among the young. according to a survey published by the globally leading market research firm, ac nielsen, “nearly % of chinese young people have joined the army of slimming”. “slimming” campaign has enabled young people to have vision, hope, relaxation and happiness. hence the young people who advocate “slimming” are faithful followers of beauty fashion. . plastic and cosmetic surgery is hot the passion for beauty is human being’s nature. whoever you are and whatever you look like, you are born to love beauty, and there is no exception. with the improvement of people’s living standards and the upgrading of people’s psychological needs, loving and seeking beauty have become a crucial part of people’s daily life. under the circumstances of beauty fashion, the contemporary youth even considers beauty as an asset. they all are dreaming to look like a celebrity, in particular, some young women are even eager to have a zhou xun’s chin, zhao wei’s eyes, and zhang ziyi’s face. therefore, the plastic and cosmetic surgery industry has become a beauty workshop where the young people are enabled to be a beauty, which makes the dream of “thousands of people have a same look” become a reality. the contemporary youth called the past year— as an “artificial beauty” year. the confidence on the part of the young in plastic and cosmetic surgery has been enhanced with the emergence of “artificial beauty”. they believe that beauty is created, and through plastic surgery, they themselves will look younger and more beautiful. in this sense, many cosmetic plastic surgeries such as cosmetic tattoos on eyebrow, eye liner, and lips, lash lengthening, polymer synthesis double- fold eyelid, pouch removing without scars, painless wrinkles lifting, laser spot removal, e-whitening, artificial dimples, breast implant through soft tissue injection, and ultrasound emulsified liposuction have attracted a number of young people to have a try. this leads to a fact that the contemporary youth population has gradually formed the biggest army of cosmetic plastic surgery. however, since young men and women often do not have a right and profound understanding of their physical condition before cosmetic plastic surgery and also the expected effect thereafter, it is highly common to see some physical as well as mental traumas caused by blind cosmetic plastic surgery and surgery at a lower age. conclusion as one scholar goes, “social fashion is playing a remarkable role in changing mainstream ideology and upgrading values (deng & ren, ).” “it is easy for the young to show their contradictory side in the process of growing up: the collision of passion and reason, assertive personality, confused but optimistic views of life and values (deng & ren, ).” therefore, we should not ignore the negative impact of beauty fashion and the cognitive biases caused by it while appreciating and enjoying beauty fashion’s leading young people’s pursuit of beauty and giving young people passion for life. we should guide the youth to have a positive, good, and sound attitude copyright © canadian academy of oriental and occidental culture i m p a c t o f b e a u t y f a s h i o n o n contemporary chinese youth towards beauty fashion, so that they could grow up healthily and happily under the influence of beauty fashion. references deng, z. m., & ren, y. m. ( ). i choose and i like— contemporary social fashion and college students. beijing: china youth publishing house. deng, z. m., & ren, y. m. ( ). social fashion and contemporary youth. chongqing: southwest china normal university press. yang, w. ( ). this way of beatification can stimulate self- confidence. china beauty fashion. zhang , j. f. ( ). modern youth psychology. chongqing: chongqing press. beauty photoproduction at hera s. miglioranzis. miglioranzi ucl / argonne national lab. th international conference on b-physics at hadron machines assisi (perugia), italy. june - , outline: introduction to beauty production at hera b measurements using different tagging techniques comparison of data to mc(lo) and nlo predictions on behalf of the h and zeus collaborations hera collider the world's only ep collider h and zeus integrated luminosity: √s ~ gev e ( . gev) - / - - / - e+ l ~ / pb- e- l ~ / pb- ~ pb- ? p ( gev) b production in ep collision dominant production process in ep collision:dominant production process in ep collision: bboson oson ggluon luon ffusionusion multiple scales involved: m b ~ gev q ≤ gev (photoproduction – p)γ q ≥ gev (deep inelastic scattering – dis) p t b ~few gev (event selection:p t jet > , gev) powerful tool for testing p structure powerful tool for testing p structure and pqcdand pqcd resolved photon: flavour excitation b production in ep collision massivemassive scheme ffns (heavy quarks dynamically generated in the hard process) monte carlomonte carlo: leading order + parton shower models available, including flavour excitation, dglap evolution (pythia , herwig) ccfm evolution with k t factorisation (cascade) theoretical calculationtheoretical calculation: full nlo calculation (fmnr) available parton shower b tagging techniques jets + jets + µ beauty eventsµ beauty events large b-mass pp tt relrel: pt of mu relative to jet axis: pt of mu relative to jet axis long b-lifetime : δ μ: δ μ impact parameter impact parameter μ + jets and δ (h ) simultaneous -dimensional ptrel and fitδ data - ( pb- ) data tend to rise more steeply then nlo qcd at low p t μ q < gev . . gev - . <η μ < . p t jet> ( ) gev |η lab jet|< . enhanced statistics and reduced systematic uncertainties μ + jets and δ : comparison h - zeus agreement within errors of h and zeus agreement within errors with massive nlo qcdnlo qcd (fmnr) h : ptrel + delta , (hep-ex/ ) zeus: ptrel , (hep-ex/ ) lifetime tagging (h ) h preliminary s s ( track associated to jet) significance of the track s s (≥ tracks associated to the jet) second highest significance enhanced sensitivity to b advantageadvantage: higher statistics w.r.t. d* or lepton analysis inclusive sample (all tracks p t > mev) extract b and c fraction from fit to subtracted significance distributions significance = dca/σ(dca) lifetime tagging (h ) main difference between beauty data and nlo qcd nlo qcd in region +ve rapidity large contribution from resolved photon events to the xsections pythiapythia and cascadecascade (lo+ps): good shape description but generally data higher in normalisation (factors ~ . , . ) h preliminary x γ (h & zeus) xx γγ jetjet = Σ = Σ j ,j j ,j (e(e-p-p zz ) / Σ) / Σ hh (e-p(e-p zz )) lifetime tagging +μ jets gg bb b-excitation:bg gb → → at lo qcd xx γγ is the fraction of photon's energy entering the hard interaction xx γγ ≤ . ≤ . h beauty from di-μ events b double tag ep bbx x'→ →μμ →d* x'μ full phase space for beauty production low p t threshold for muon identification large rapidity coverage of zeus muon system low background di-mu selection separation of the sample in high-low mass, isolated and non-isolated,like and unlike-sign muon pair direct measure total bb cross section without any cutsdirect measure total bb cross section without any cuts - charm pair productioncharm pair production contributes to the unlike-sign muon sample only and was estimated from d*+muon analysisestimated from d*+muon analysis - fake muon bkg fake muon bkg was removed by taking the difference between like sign and unlike sign samples (lfl contribution cancels) beauty from di-μ events (zeus) what is left is only beauty contribution...what is left is only beauty contribution... low+high mass unlike sign beauty from di-μ events (zeus) zeus preliminary beauty from di-μ events (zeus) zeus preliminary agreement in shape with mc (lo+ps) p t μ> . gev - . <η< . for ΔΦ additional request: true level: μ coming from different bs rec level: m μμ > . gev d* + μ events (h ) this measure extends to significantly lower centre-of-mass energies of bb system than previous hera xsections. simultaneously detection of d* and test high order qcd effectsμ d* sensitive to a possible transverse momentum kμ t of the gluons entering the quark pair production process deviations from lo -> high order effects, good agreement with nlo d* + μ events (h & zeus) σ b vis(ep ed* x)= ± (stat.)± (syst.)pb→ μh : zeus: σb vis(ep ed* x)= ± (stat.)→ μ + - (syst.)pb μμ php (zeus) d* μ php (zeus) d* μ dis (zeus) d* μ php (h ) hera ii : μ + jets and δ (zeus) zeus vertex detector since upgrade first zeus result using impact parameter technique summary p t rel, and significance measurements have been performed in php:δ - h and zeus measurements agreeh and zeus measurements agree - general agreementgeneral agreement at large p at large p t t of beauty data with of beauty data with nlo qcdnlo qcd - h data slightly higher at low p t μ,p t jet (observed also in dis) hera ii is running smoothly in e- mode improved analysis and detector performances (e.g. zeus mvd) high precision results are coming... analysis with jets: double tag analysis: d* and di- measurements (μ μ sensitive at low pp tt ) have been presented ) have been presented - - beauty data larger than nlo qcdbeauty data larger than nlo qcd outlook inclusive b-quark cross section extrapolation to ep-> ebx good agrement with nlo qcd backup slides data/theory backup slides simultaneous -dimensional ptrel and fitδ enhanced statistics and reduced systematic uncertainties data - ( pb- ) data tend to rise more steeply then nlo qcd at low p t μ,p t jet q < gev . . gev - . <η μ < . p t jet> ( ) gev |η lab jet|< . backup slides s xjra .. the terminology for beauty in the iliad and the odyssey an ancient greek proverb declares: ‘beautiful things are difficult’. one obvious diffi- culty arises from their almost limitless variety: sights, sounds, people, natural phenom- ena, man-made objects and abstract ideas may all be beautiful, but what do these things have in common? it is not just beauty’s breadth of application, then, that makes it dif- ficult, but the way in which its meaning varies depending on context. the beauty of a child may mean something quite different from the beauty of an old and wizened face, let alone the beauty of a supermodel. in common parlance, beautiful may be used as a general term of approbation alongside others like lovely or fine, while in academic dis- course, the word beauty has a life of its own: since the emergence of aesthetics as an independent discipline in the mid eighteenth century, beauty has been constantly theorized and responded to in different ways that have laden the term with its own pecu- liar historical baggage. and although some of these philosophical reflections on beauty may have trickled into the common cultural consciousness, in general they seem a far cry from beauty’s most ubiquitous incarnation in modern western society, in the cosmetics industry; to put it another way, if you go into a beauty salon in search of a kantian ideal of disinterested contemplation, i suspect you will be disappointed. all this goes to show that beauty is a protean beast, notoriously slippery in the hands of those who try to define it. the lack of a clearly defined concept of beauty certainly poses a challenge to those wishing to explore ancient attitudes to beauty, but it is not insurmountable. the enquiry calls for an approach that is attentive to the historical contingency of our ideas and the potential discrepancies between ancient and modern conceptual categories. from our brief sketch of beauty’s various modern uses and permutations, it is clear that we should not expect to find a greek concept that bears pl. hp. mai. e: χαλεπὰ τὰ καλά. i am very grateful to i.j.f. de jong, j. elsner, r.l. hunter, c. metcalf, m. paprocki, r.c.t. parker and cq’s anonymous readers. their patience, criticism and encouragement have been invaluable in helping me through these ‘difficult beautiful things’. for some recent approaches to beauty and its modern history, see n. zangwill, the metaphysics of beauty (ithaca, ); w. steiner, venus in exile: the rejection of beauty in twentieth-century art (chicago, ); a.c. danto, the abuse of beauty: aesthetics and the concept of art (chicago, ); e. prettejohn, beauty and art (oxford, ); a. nehamas, only a promise of happiness: the place of beauty in a world of art (princeton, ); r. scruton, beauty (oxford, ); j. brouwer, a. mulder and l. spuybroek (edd.), vital beauty: reclaiming aesthetics in the tangle of technology and nature (rotterdam, ); a. chatterjee, the aesthetic brain: how we evolved to desire beauty and enjoy art (oxford, ); p.c. hogan, beauty and sublimity: a cognitive aesthetics of literature and the arts (cambridge, ). on the challenges in studying ancient aesthetics, see j.i. porter, the origins of aesthetic thought in ancient greece: matter, sensation, and experience (cambridge, ), – ; p. destrée and p. murray (edd.), ‘introduction’, in p. destrée and p. murray (edd.), a companion to ancient aesthetics (chichester, ), – . the classical quarterly . – © the classical association ( ) doi: . /s x of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core precisely the same range and depth of meanings. but what common features make beauty identifiable across time and place? in general terms, beauty pertains to the attract- ive way in which things appear. at the most basic level of perception, beauty pleases: beautiful things attract and demand our attention because they please us. yet, beyond this basic element of pleasure, any number of emotional and cognitive responses to beauty is possible: delight, desire, wonder, sadness, even fear. the important point is that beauty is affective. to call something ‘beautiful’ is to make a claim not just about how something appears but about how it makes you feel. what is at stake is a special kind of relationship between appearance and experience, between the properties of perceptual objects and the effects they have. nowhere is this clearer than in homer’s representation of helen, whose beauty is conveyed not just by her appearance ‘like the immortal goddesses’ but by its extraordinary agency over the greeks and the trojans: her appearance is a justifiable cause, so the trojan elders say, for ten years suffering in war. this paper investigates some of our earliest literary evidence for greek views on beauty: the iliad and the odyssey. how does homer express beauty? what words, if any, does he have for ‘beauty’ and ‘beautiful’? how else does the poet express beauty without an explicit word for ‘beauty’ or ‘beautiful’? semantic studies on greek beauty have focussed almost exclusively on the adjective καλός, though david konstan’s recent work has brought its cognate noun κάλλος into the picture. the greek termin- ology for beauty, however, was far from limited to a single semantic family. what we find in the iliad and the odyssey is a rich and diverse terminology for expressing beauty in nuanced ways. to achieve a well-rounded understanding of homeric and early greek attitudes to beauty, therefore, we must interrogate these various ways of expressing beauty, their relationship with one another and with our own ideas about beauty. exploring ancient attitudes to an unstable concept such as beauty must begin as an exercise in translation, ever attentive, in matthew arnold’s words, to ‘the shade, the fine distinction’ of semantic meaning. i. ‘beauty’ and ‘beautiful’ as the most prolific word in homer’s terminology for beauty, καλός seems an appro- priate place to begin. with over three hundred appearances, καλός is one of the most common adjectives in the homeric poems, applied to everything from people, animals and armour, to songs, buildings and natural phenomena. in most cases, ‘beautiful’ is an it is for this reason that beauty is not coterminous with attractiveness (although inextricably linked) and why ‘beautiful’ is different from ‘pretty’, which is purely pleasing; beauty cannot therefore be reduced, in tolstoy’s words, to ‘nothing other than what is pleasing to us’. see l. tolstoy, what is art? (london, [ ] ), . on the relationship between beauty and attractiveness, see nehamas (n. ), – . hom. il. . – . d. konstan, beauty: the fortunes of an ancient greek idea (oxford, ); d. konstan, ‘beauty’, in p. destrée and p. murray (edd.), a companion to ancient aesthetics (chichester, ), – ; d. konstan, ‘beauty and desire between greece and rome’, in d. cairns and l. fulkerson (edd.), emotions between greece and rome (london, ), – . m. arnold, on translating homer (london, ), . on the importance of sensitivity to semantics when analysing foreign notions of beauty, see c. sartwell’s six names of beauty (new york, ). cf. tlg s.v. καλός; lfgre s.v. καλός. hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core apt translation of καλός in its denotation of a general attractive aspect of appearance common to such a broad spectrum of visible and audible objects. the same applies to the cognate adjective περικαλλής, which intensifies the meaning of καλός and is only applied to visible objects in homer; in signifying attractive physical appearance, it may be rendered as ‘most beautiful’ or ‘exquisite’ in each case. significantly, however, καλός also shades towards meaning simply ‘good’: ‘it is kalos to do this’, for instance, is a standard way of saying ‘it is good/appropriate to do this’. whether καλός designates an aspect of appearance or quality, therefore, is often hard to disentangle, especially for material objects: does τεύχεα καλά mean ‘beautiful armour’ or ‘good armour’ in the sense of ‘well-made’? the semantic range of καλός seems to imply that if something looks good, then it is good. as a result, some scholars have wondered whether the greeks were even able to differentiate between (say) a person’s beauty and their moral virtue, or between a material object’s beauty and its quality of manufacture. the latter case—to which we will return—is certainly difficult, but when it comes to people, homer clearly shows that καλός can denote beauty without implying moral virtue or excellence of character. the obscure greek soldier nireus is described as ‘the most beautiful [κάλλιστος] man that came to troy … after the blameless son of peleus [achilles]; but he was weak [ἀλαπαδνός] and few people followed him.’ that nireus was κάλλιστος, ‘most beautiful’, clearly does not imply that he was also especially excellent in character, for he lacks the heroic essentials of strength and a large following. in another instance, however, καλός signifies precisely the kind of appearance that manifests nobility and prowess. at the sight of agamemnon, priam eulogizes: he comments how he is ‘good and big’ (ἠΰς τε μέγας τε) and claims: ‘never have i seen with my eyes a man so kalos, nor so majestic; for he has the look of a king.’ the emphasis on regal and majestic appearance suggests that καλός here means something closer to ‘noble in appearance’ than ‘beautiful’. the examples of nireus and agamemnon show that (in homer at least) καλός connotes no single claim to the relation between appearance and character: the adjective can convey both the superficial beauty of nireus and the noble and distinguished appearance that affirms agamemnon’s status as the most powerful achaean king. ranging from ‘beautiful’ to ‘noble in appearance’ for people, and from ‘beautiful’ to περικαλλής appears fifty-five times in homer and is applied to a diverse range of physical objects (chariots, houses, armour, people, etc.). in the odyssey (e.g. od. . , . ), κάλλιμος also appears, which is entirely synonymous with καλός. e.g. hom. il. . ; od. . – . see lfgre s.v. καλός ( b). cf. konstan (n. [ ]), – . cf. pl. hp. mai. c– d; xen. mem. . . – ; arist. eth. eud. a. there seems no substantive difference, moreover, between the homeric epithets καλλίζωνος (‘beautiful-girdled’) and εὔζωνος (‘well-girdled’); καλλίκομος (‘beautiful-haired’) and ἠύκομος (‘fair-haired’); καλλιπλόκαμος (‘of beautiful locks’) and ἐυπλόκαμος (‘of fair locks’); καλλίρροος (‘beautiful-flowing’) and ἐύρροος (‘fair-flowing’). it is because of this slippage between appearance and quality that καλός is most often translated as ‘fine’; see n. below. see a. kosman, ‘beauty and the good: situating the kalon’, cph ( ), – ; g.r. lear, ‘response to kosman’, cph ( ), – , especially . cf. u. eco, history of beauty (new york, ), . hom. il. . – . cf. paris, who is similarly distinguished by his beauty but deficient in heroic excellence; see hom. il. . – , . – . so, too, euryalus at od. . – . hom. il. . – . on the semantic development of καλός after homer, see konstan (n. [ ]), – . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core ‘good’ for objects and ideas, καλός both subsumes and surpasses the range of the english word beautiful. to understand how καλός relates to other homeric terms and expressions for beauty, we must explore the common properties of things that are καλός and what responses they evoke. priam’s description of agamemnon introduces one of the most common properties: bigness. in his own words, achilles is ‘beautiful and big’ (καλός τε μέγας τε), just like ares and athena on his shield, ‘beautiful and big in their armour (καλὼ καὶ μεγάλω σὺν τεύχεσιν). throughout homeric epic, men and women described as καλός are often big, and this also applies to animals and material objects: rhesus’ horses are ‘the most beautiful … and biggest’ (καλλίστους … ἠδὲ μεγίστους); hecuba’s peplos for athena is ‘most beautiful in its embroideries and biggest’ (κάλλιστος … ποικίλμασιν ἠδὲ μέγιστος). radiance is another outstanding quality of things that are καλός, like hecuba’s peplos, which ‘shone like a star’ (ἀστὴρ δ’ ὣς ἀπέλαμπεν). the homeric lexicon contains a panoply of terms to convey the radiance often possessed by things that are καλός: hera’s tresses are ‘shining, beautiful’ (φαεινοὺς καλούς); her ‘beautiful veil … was white like the sun’ (κρηδέμνῳ … καλῷ … λευκὸν δ’ ἦν ἠέλιος ὥς); ‘the brightness of achilles’ beautiful, cunningly wrought shield reached heaven’ (Ἀχιλλῆος σάκεος σέλας αἰθέρ’ ἵκανε | καλοῦ δαιδαλέου). achilles’ shield exemplifies another feature characteristic of καλός objects: skilful manufacture, illustrated most often by the juxtaposition of καλός with δαιδάλεος, derived from δαιδάλλω, ‘to work cunningly’, ‘embellish’. like its cognates δαίδαλος and πολυδαίδαλος, δαιδάλεος contains not only a sense of craft but also quality, intricacy and skill in craftsmanship. their common association with καλός objects therefore underpins the slippage between an object’s beauty and excellence of kind implied by the semantic range of καλός. similar to δαιδάλεος in its range of application, association with καλός objects, and connotation of intricate, skilful manufacture is the adjective ποικίλος, which also variously denotes polychromy, for more on καλός, see lfgre: s.v. καλός; k.j. dover, greek homosexuality (london, ), – , ; r. barney, ‘notes on plato on the kalon and the good’, cph ( ), – ; t.h. irwin, ‘the sense and reference of the kalon in aristotle’, cph ( ), – ; a. ford, ‘response to irwin’, cph ( ), – . hom. il. . , . . for other examples of καλός and bigness for people, see hom. od. . , . , . , . , . – , . , . , . . hom. il. . . cf. od. . . hom. il. . . cf. il. . – ; od. . , . – , . . hom. il. . . on the aesthetics of radiance in greek culture, see r.a. prier, thauma idesthai: the phenomenology of sight and appearance in archaic greek (tallahassee, ), – ; e. parisinou, the light of the gods: the role of light in archaic and classical greek cult (london, ); r. neer, the emergence of the classical style in greek sculpture (chicago and london, ), passim especially – ; konstan (n. [ ]), . e.g. αἴγλη, αἰόλος, ἀστερόεις, αὐγή, γανόω, λάμπω, λιπαρός, μαρμαίρω, παμφαίνω, σέλας, σιγαλόεις, etc. cf. hom. il. . – , . – ; od. . – , . – . hom. il. . – . hom. il. – . hom. il. . – . see hom. il. . ; od. . , etc. cf. a. bergren, ‘plato’s timaeus and the aesthetics of “animate form”’, in r.d. mohr and t. sattler (edd.), one book, the whole universe: plato’s timaeus today (las vegas, ), – , at – , where she links aspects of ‘homeric beauty’ with plato’s demiurgic narrative in the timaeus. on δαίδαλος, see s.p. morris, daidalos and the origins of greek art (princeton, ). hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core elaborate adornment and embroidery. antinous gives penelope, for instance, ‘a big, most beautiful peplos, intricately embroidered in many colours’ (μέγαν περικαλλέα πέπλον, | ποικίλον). in addition to bigness, radiance and skilful manufacture, the precious metals gold, silver and bronze have an important place in the catalogue of common properties of things that are καλός. menelaus’ ‘most beautiful’ (κάλλιστον) treasure is a mixing- bowl ‘all of silver, its rims finished with gold’ (ἀργύρεος … ἅπας, χρυσῷ δ’ ἐπὶ χείλεα κεκράανται). encapsulated by the prolific expression καλός χρύσειος, ‘beau- tiful, golden’, the association of καλός with gold is particularly strong. so much for the physical properties of things that are καλός. what about their effects? desire and wonder stand out. hermes ‘desired’ (ἠράσατ’) polymele, ‘beautiful in the dance’ (χορῷ καλή), just as tyro ‘desired’ (ἠράσσατ’) enipeus, ‘the most beau- tiful of rivers’ (κάλλιστος ποταμῶν). the sight of athena’s ‘most beautiful light’ (φάος περικαλλές) is a ‘wonder’ (θαῦμα) to telemachus, while hephaestus assures thetis that he will make for achilles ‘beautiful armour [τεύχεα καλά], such that any mortal man will wonder at [θαυμάσσεται]’. pleasure and delight are pervasive responses to mousikē in homer and, although music, dance and song need not be καλός to have this effect, the connection is discern- ible on a number of occasions. apollo ‘took pleasure’, ‘delighted as he listened’ (τέρπετ’ ἀκούων) to the achaeans singing ‘the beautiful paean’ (καλὸν … παιήονα). likewise, the sirens sing to odysseus in their ‘beautiful voice’ (ὄπα κάλλιμον) that if he stay with them a while, he will go on his way ‘having delighted … and knowing more’ (τερψάμενος … καὶ πλείονα εἰδώς). allied with the promise of knowledge, the ‘beautiful’ quality of the sirens’ song—otherwise described as ‘clear’ (λιγυρός) and ‘sweet-voiced’ (μελίγηρυς)—seems to contribute to its power to please and ‘charm [θέλγουσιν] all men’. in other words, it is at least part of what makes the sirens’ song so deadly—attracting, pleasing and luring men to their deaths. the immediate context might suggest the pleasing effect of the sirens’ ‘beautiful voice’, like δαιδάλεος, ποικίλος applies above all to objects of metalwork, carpentry and embroidery. on the parallel between them, see f. frontisi-ducroux, dédale. mythologie de l’artisan en grèce ancienne (paris, ), – ; bergren (n. ), – . on ποικιλία, see e. berardi, f.l. lisi and d. micalella (edd.), poikilia. variazioni sul tema (acireale, ); a. grand-clément, ‘poikilia’, in p. destrée and p. murray (edd.), a companion to ancient aesthetics (chichester, ), – . hom. od. . – . cf. il. . – , . . ποικίλος is most commonly applied to armour in homer (τεύχεα ποικίλα, e.g. il. . , . , . , etc.). it seems no coincidence that the most common adjective applied to armour (τεύχεα and ἔντεα) in homer is καλός. e.g. hom. il. . – ; od. . , etc. hom. od. . – . see hom. il. . – ; od. . , etc. hom. il. . – ; od. . – . cf. il. . – ; od. . – . hom. od. . – ; il. . – . cf. il. . – , . – ; od. . – . on the relation between wonder and beauty for material objects in archaic epic, see c. hunzinger, ‘le plaisir esthétique dans l’épopée archaïque: les mots de la famille de θαῦμα’, bulletin de l’association guillaume budé ( ), – . cf. neer (n. ), especially – . on the pleasures of mousikē in homer and elsewhere in greek literature, see a.-e. peponi, frontiers of pleasure: models of aesthetic response in archaic and classical greek thought (oxford, ). hom. il. . – . hom. od. . – . cf. od. . . hom. od. . – , , . on the power of the sirens’ song, see peponi (n. ), – . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core but the broader narrative complicates and enriches the picture: the pleasing effect of their song is the sirens’ weapon of deception. a good point of comparison is odysseus’ tearful response to demodocus’ song about the trojan horse, which prompts alcinous to interrupt the song, ‘for it is not pleasing [χαριζόμενος] to all’, and to ask odysseus who he is. odysseus reassures his host that there is ‘nothing more pleasing’ (οὐ … τέλος χαριέστερον) than precisely his present situation: when ‘good cheer’ abounds among people as they dine, listen to a bard, and enjoy food and wine in plenty. ‘to me’, odysseus says, ‘this seems to be the most beautiful thing’ (τοῦτό τί μοι κάλλιστον ἐνὶ φρεσὶν εἴδεται εἶναι). but because of his personal investment in the subject of demodocus’ song, odysseus’ response to this ‘most beautiful’ situation is not unalloyed pleasure but intense sadness. this inversion of the expected affect is underscored by odysseus’ reference to his ‘grievous troubles’ (κήδεα … στονόεντα) immediately after his portrayal of ‘this most beautiful thing’. so although pleasure may be the expectation, narrative context—in this case, odysseus’ personal story—conditions and complicates the response to καλός. desire, wonder, pleasure, even sadness: the adjective καλός is tied to an affective register in homer and closely associated with a set of physical properties, namely big- ness, radiance, skilful manufacture and precious metals. in their range of effects, καλός things present no great discrepancies with how beautiful things may affect us now, though there is no question that καλός is broader than the english adjective in its range of signification from ‘beautiful’ to ‘good’. by contrast, its cognate noun κάλλος is far more limited than our notion of beauty. this is true for both its range of application and its meaning. while we may speak of the beauty of people, objects, ideas and practically anything else, for fifteen of its six- teen appearances in homer, κάλλος is applied to anthropomorphic appearance. the exception is a ‘well-made silver mixing-bowl’ (ἀργύρεον κρητῆρα τετυγμένον) presented as a prize in the funeral games for patroclus: ‘it could hold six measures, and surpassed in beauty [κάλλει ἐνίκα] all others in the whole world, since sidonians, skilled in crafts, fashioned it well [πολυδαίδαλοι εὖ ἤσκησαν].’ the large size of the mixing-bowl, the fact that it is silver, and the emphasis on its expert manufacture—denoted by τετυγμένον and πολυδαίδαλοι εὖ ἤσκησαν—recall the outstanding properties of objects that are καλός. the effect of the mixing-bowl’s ‘beauty’ is not explicit. but since it is presented as first prize in the contest, it seems reasonable to infer that its pre-eminent ‘beauty’ enhances its desirability as a possession for the victor. this is underpinned by κάλλος’ application to people, where it has a strong connec- tion with desire, as konstan has highlighted. the desire inspired by κάλλος is often either implicitly or explicitly sexual. homeric women are courted and married ‘for the sake of their kallos’, and men like ganymede and cleitus abducted by the gods compare hera’s seduction of zeus, where her beautiful appearance inspires zeus’s ‘desire’ (hom. il. . ) and therefore effects her deception. hom. od. . . hom. od. . – . hom. od. . – . cf. peponi (n. ), . penelope’s sorrow in response to phemius’ song about the return of the achaeans parallels odysseus here (hom. od. . – ). for the same reason, there is not a dry eye among the achaeans as they listen to the dirge for achilles sung by the muses ‘with their beautiful voice’ (ὀπὶ καλῇ) (hom. od. . ). hom. il. . – . see konstan (n. [ ] and [ ]). hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core ‘on account of their kallos’. and like other desirable human attributes, κάλλος is presented as a divine blessing: heroes and heroines are said to have ‘beauty from the gods’ (θεῶν ἄπο κάλλος). in odyssey book homer envisages a very literal take on this epic formula, as athena endows penelope with ‘immortal gifts in order that the achaeans would marvel [θηησαίατ’] at her’; athena’s motivation for this ploy is that penelope ‘win greater honour from her husband and son’. athena washes penelope’s face with ‘immortal beauty’ (κάλλεϊ … ἀμβροσίῳ), presented here like a physical ointment that aphrodite uses when ‘she joins the desirable [ἱμερόεντα] dance of the charites’. and ‘she made her bigger and fuller in appearance, and whiter than sawn ivory’ (μακροτέρην καὶ πάσσονα θῆκεν ἰδέσθαι, | λευκοτέρην δ’ ἄρα μιν θῆκε πριστοῦ ἐλέφαντος). the erotic power of penelope’s divinely endowed κάλλος is palpable: at the sight of her, the suitors went ‘weak at the knees, their hearts charmed by eros [ἔρῳ δ’ ἄρα θυμὸν ἔθελχθεν], and they all prayed to go to bed with her’. so the achaeans marvel at penelope as athena intended, while the deceptive poten- tial of penelope’s erotic beauty is suggested by the use of the verb ἔθελχθεν, ‘charmed’, ‘beguiled’. in this state of erotic enchantment, the suitors are easily exploitable, as penelope coaxes from them a shower of gifts vainly hoped to win her affection— much to odysseus’ delight, for he recognizes penelope’s ulterior motives. and so athena achieves her aim of enhancing penelope’s honour in the eyes of her husband. the narrative sequence therefore reveals how the goddess harnesses the erotic agency of κάλλος to manipulate the suitors and benefit odysseus and penelope. the suitors’ immediate response and the narrative sequence underline the noun’s strong connection with desire. unlike its cognate adjective καλός, the noun κάλλος in homer is limited in its range of meaning and application: it unambiguously signifies ‘beauty’ in the narrow sense of desirable physical appearance. yet, something of the conceptual breadth of the modern notion of beauty is approximated by the greek noun χάρις, derived from the indo-european ancestor *gher- meaning ‘pleasure’, ‘delight’. χάρις has two essential spheres of meaning. on the one hand, it refers to an ideal of social reciprocity, of ‘pleasure’ from favours given and received. on the other, χάρις signifies an aesthetic quality possessed by people, objects and immaterial things that attracts, charms and pleases. in this context, χάρις approximates the modern notion of beauty, as some scholars have recognized. hom. il. . – ; od. . – ; il. . – ; od. . . cf. il. . – , . – . hom. od. . – , . ; il. . – . cf. hom. hymn . ; hes. cat. . . hom. od. . . hom. od. . – . hom. od. . . hom. od. . – . on female beauty in greek poetry, see k. jax, die weibliche schönheit in der griechischen dichtung (innsbruck, ). hom. od. . – . hom. od. . – . cf. konstan (n. [ ]), . penelope’s reference to telemachus’ κάλλος at hom. od. . – is the only instance in homer where the noun has no obvious link with desire. for the etymology of χάρις, see b. maclachlan, the age of grace. charis in early greek poetry (princeton, ), ; r.s.p. beekes, etymological dictionary of greek (leiden, ), s.v. χαίρω. see maclachlan (n. ), especially – , – ; r. parker, ‘pleasing thighs: reciprocity in greek religion’, in c. gill, n. postlethwaite and r. seaford (edd.), reciprocity in ancient greece (oxford, ), – . see maclachlan (n. ), – , – ; g. nagy, homer the preclassic (berkeley, ), . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core the relationship between χάρις and κάλλος as greek words for ‘beauty’, however, has been neglected. so how do they compare and what can this tell us about homeric and early greek attitudes to beauty? after odysseus’ supplication of nausicaa in odyssey book , athena steps in as his personal beautician: she pours ‘charis on his head and shoulders’, makes his hair like flowers of hyacinth and, as she did for penelope, makes him ‘bigger and stouter’ (μείζονά … καὶ πάσσονα). just as bigness reappears, so too gold and silver: athena enhances odysseus’ appearance with χάρις like a craftsman overlaying silver with gold in the creation of ‘pleasing works’ (χαρίεντα … ἔργα). odysseus thus appears κάλλεϊ καὶ χάρισι στίλβων, ‘glistening with kallos and charis’; evidently a seductive sight, as nausicaa ‘marvelled’ (θηεῖτο) at him, quietly longing for such a man to be her husband. the synonymity of κάλλος and χάρις here is remarkable: ‘glistening with desirable beauty and pleasurable beauty’ (though an ugly translation) perhaps best conveys their similarity and subtle distinction. yet, when athena beautifies odysseus to facilitate his long-awaited reunion with penelope, even that distinction is blurred. introduced with athena pouring ‘much kallos’ on odysseus, the passage concludes with ‘so she poured charis on his head and shoulders’. κάλλος and χάρις thus appear interchangeable as homeric words for ‘beauty’. the difference between the two nouns becomes clear, however, when athena pours χάρις on odysseus before the assembled phaeacians. again she makes him ‘bigger and stouter’ (μακρότερον καὶ πάσσονα), and here the goddess’ purpose is explicit: she enhances his appearance with χάρις ‘in order that he would be philos to all the phaeacians and deinos and aidoios’. as before, odysseus’ χάρις has a pleasing effect, the sort that may make the phaeacians ‘marvel [θηήσαντο] at the sight of him’, and make him φίλος—‘dear’, ‘welcomed’, ‘loved’. but this pleasing effect is untouched by the erotic overtones that characterized the appearances of χάρις alongside κάλλος in the episodes with nausicaa and penelope. in contrast, this χάρις may engender the perception of odysseus as δεινός τ᾽ αἰδοῖός τε, ‘respected and revered’, two qualities that in homer underline social authority. though at times interchangeable, therefore, χάρις differs from κάλλος in its greater freedom from desire. both nouns point to an attractive aspect of appearance that pleases and inspires aesthetic admiration: signified by the verb θηέομαι, beholders ‘marvel’, ‘gaze in wonder’ at χάρις and κάλλος. furthermore, they are both connected with gold, silver hom. od. . – . hom. od. . – . hom. od. . – . i take the translation of χάρις as ‘pleasurable beauty’ from nagy (n. ), . because of its similar range of social and aesthetic meaning, ‘grace’ is the most common translation of χάρις. though sometimes useful as an approximation—‘glistening with beauty and grace’, for example— there are some problems with this translation. first, ‘grace’ does not capture the importance of pleas- ure to χάρις. second, grace’s strong connection with christian theology is potentially misleading: since χάρις is a fundamental concept in ancient greek religion, there is a danger in over-assimilating greek χάρις with christian grace. third, in denoting beauty with respect to motion, posture and elegance of proportions, grace is in fact more specific than χάρις in its aesthetic meaning. hom. od. . – . hom. od. . – . hom. od. . . cf. g. pasquali, terze pagine stravaganti (florence, ), . cf. hom. il. . , . ; od. . . see hom. od. . , . , . , . – . on θηέομαι, see v.h.j. mette, ‘“schauen” und “staunen”’, glotta ( ), – . hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core and impressive stature, and both represented as forms of radiance: like odysseus, paris ‘glistens with kallos’ (κάλλεΐ τε στίλβων), and ‘charis shone from’ (χάρις δ’ ἀπελάμπετο) the earrings of hera and penelope. but while κάλλος is bound to desirability, the ‘pleasurable beauty’ denoted by χάρις embraces a broader spectrum of pleasing and compelling appearances, both those that are erotically attractive and those that provoke reverence and respect. in this way, homer’s use of χάρις is closer to the modern notion of beauty than his use of κάλλος. just as the beauty of a supermodel and of an old and wizened face may come together despite their differences under beauty’s broad conceptual wing, so might χάρις embrace such a range of appearances, all endowed with the power to please our eyes and mind but for very different reasons. χάρις’ greater range of application than that of κάλλος in homer reaffirms its greater proximity to the modern notion of beauty. with one exception (achilles’ mixing-bowl), κάλλος is exclusively applied to anthropomorphic appearance in homer. by contrast, χάρις denotes a kind of ‘beauty’ possessed not just by people and objects but by words and deeds as well. it seems then that χάρις signifies an aesthetic property com- parable to the modern notion of beauty in both its conceptual breadth and its range of application. at their core, homeric χάρις and modern beauty share a broad sense of pleasure-bearing power. the same power to please characterizes the noun’s derivative adjective χαρίεις. although something may be χαρίεις—‘pleasing’, ‘attractive’—for any reason, the adjective is most often applied to visible objects such as clothes and human features, where the sense is ‘physically attractive’, that is, the conventional meaning of beautiful. as we might expect, therefore, the adjectives χαρίεις and καλός sometimes work in tandem as equivalent aesthetic terms like their cognate nouns: helenus recommends the ‘most attractive’ (χαριέστατος) peplos as an offering for athena, and hecuba duly chooses the peplos that is ‘most beautiful’ (κάλλιστος). as homeric terms for ‘beauty’ and ‘beautiful’, the καλός–κάλλος and χάρις–χαρίεις semantic families dem- onstrate a high degree of conceptual overlap and interconnection, discernible in their range of meanings, associated affects and physical properties. that said, each term has its own peculiar aesthetic connotations, whether it is the ontological associations of the adjective καλός, the noun κάλλος’ connection with desire, or the broad idea of pleasure-bearing power conveyed by χάρις and χαρίεις. yet, homer has a further set of words meaning ‘beauty’ and ‘beautiful’ in nuanced ways: the adjective ἀγλαός and its derivative noun ἀγλαΐη. the adjective ἀγλαός is applied to a variety of visual objects: gifts, prizes, people, achilles’ limbs, women’s handiwork, water and sacred groves. what common feature denoted by ἀγλαός do these diverse things possess? although it is often interpreted as connoting radiance, hom. il. . , . ; od. . . cf. hom. hymn . – . cf. hom. od. . – and . – , where athena’s dispensations of χάρις on telemachus attract aesthetic admiration untouched by desire. for discussion of beauty’s ability to embrace both the erotic and the reverential, see scruton (n. ), – ; konstan (n. [ ]), – . see hom. il. . ; od. . , . , . . cf. the brief comparison of χαρίεις and καλός in j. latacz, zum wortfeld «freude» in der sprache homers (heidelberg, ), . hom. il. . , . . for more examples of the equivalence of καλός and χαρίεις, see od. . , . ; the face and brow of achilles—the ‘most beautiful’ (κάλλιστος) greek (il. . – )—are both χαρίεις at il. . , . . the exception is hom. il. . : ἀγλαὸν εὖχος. cf. hes. theog. . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core the range and the distribution of its application suggest rather that ἀγλαός points to affect. it is noteworthy, for instance, that ἀγλαός is the most common homeric word to qualify objects given from one person to another in order to delight and honour the recipient. above all, this applies to ‘gifts’ (ἀγλαὰ δῶρα) but also to ‘ransom’ (ἄποινα) and ‘prizes’ (ἄεθλα). that ἀγλαός designates a general delightful quality is underpinned by its likely derivation from ἀγάλλομαι, ‘to delight in’, ‘exult in’, ‘be proud of’. it seems that, like the use of beautiful in colloquial expressions such as ‘what a beautiful day’, ἀγλαός is a general term of approbation with a nuance of delight. in many cases, such as water, sacred groves, achilles’ limbs and women’s handi- work, it is evidently the physical appearance of objects that makes them ἀγλαός, and here ‘beautiful’ makes an apt approximation. the adjective’s appearance in conjunc- tion with καλός and χαρίεις reinforces this sense. circe’s ‘big web’ is one of those ‘delicate and attractive and beautiful works’ (λεπτά τε καὶ χαρίεντα καὶ ἀγλαὰ ἔργα) that goddesses make; the evocation of their bigness and affective power to please (χαρίεις) and delight (ἀγλαός) underscores the expression of their beauty. likewise, achilles’ old armour is described as ‘massive, a wonder to behold, beautiful’ (πελώρια θαῦμα ἰδέσθαι | καλά); such were peleus’ ἀγλαὰ δῶρα—‘glorious/delight- ful/beautiful gifts’—from the gods. in this instance, the aesthetic properties of the armour seem instrumental to why they are ἀγλαός. but we cannot always be sure. like the potential ambiguity of objects that are χαρίεις—which may be ‘pleasing’ aesthetically or otherwise—we may wonder whether ‘gifts’ can be ἀγλαός, ‘delightful’, ‘splendid’, simply by virtue of being given rather than because of their appearance. like καλός and χαρίεις, therefore, ἀγλαός does not unambiguously signify ‘beautiful’. all three adjectives intersect with and diverge from the word beautiful in different ways—a relationship which, if nothing else, may clarify the cultural contingency of what we deem worthy of the label beautiful. the cognate noun ἀγλαΐη, by contrast, is more specific as a homeric word for ‘beauty’. for five of its eight occurrences in homeric epic, ἀγλαΐη refers to a general feature of physical appearance which only living beings—humans and animals—may possess, unlike κάλλος and χάρις which apply both to people and to material objects. unlike them, moreover, ἀγλαΐη has a special association with pride in appearance—fur- ther support, it seems, for its derivation with ἀγλαός from ἀγάλλομαι, ‘to delight in’, ‘exult in’, ‘be proud of’. this association with pride is best illustrated by homer’s the supposed link with radiance depends on a hypothetical etymological relationship with γελάω; see p. chantraine, dictionnaire étymologique de la langue grecque: histoire des mots (paris, ), s.v. ἀγλαός. for the common interpretation of ἀγλαός and ἀγλαΐη as denoting radiance, see e.g. lfgre: s.v. ἀγλαός (b); c. segal, aglaia: the poetry of alcman, sappho, pindar, bacchylides and corinna (lanham, ), – ; d.t. steiner, images in mind: statues in archaic and classical greek literature and thought (princeton and oxford, ), . e.g. hom. il. . , . , . , etc.; od. . , . , . , etc. cf. beekes (n. ), s.v. ἀγλαός; o. szemerényi, syncope in greek and indo-european and the nature of indo-european accent (naples, ), . the inference of radiance to ἀγλαός and ἀγλαΐη in modern scholarship may be owed to the fact that visually delightful things—denoted by ἀγλαός and ἀγλαΐη—are often radiant in greek literature; but this is different from these words themselves signifying radiance. see hom. il. . , . , . , etc. hom. od. . – . hom. il. . – . this also applies to ἄποινα and ἄεθλα; e.g. hom. il. . , . ; od. . , . . this connotation is reaffirmed by the two instances when ἀγλαΐη does not refer to an aspect of appearance. at hom. od. . – the connotation of pride and showiness tip over into the negative hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core simile of a horse to analogize the charge into battle of paris and hector respectively. the poet likens each to a horse that races across the plain κυδιόων, ‘exulting’, ‘bearing himself proudly’. the sense of pride in appearance continues in the description of the horse as ‘he holds his head high, and his mane streams around his shoulders’. all this amounts to the horse ἀγλαΐηφι πεποιθώς: ‘trusting in his splendour’ or ‘confident in his beauty’. allied with this element of pride, ἀγλαΐη has a connotation with superficial good looks. at the sight of his old dog argus, the disguised odysseus wonders whether the hound has speed to match his ‘fine form’ (καλὸς … δέμας) or is like one of those ‘table dogs’ that ‘masters tend for the sake of their aglaïē’, that is, ‘for their [superficial] beauty’, ‘for the sake of show’. is argus the canine equivalent of nireus, beautiful only in appearance, or, like achilles, is his beauty matched by excel- lence? in contrast to the sort of appearance that manifests ability, ἀγλαΐη is here used to denote a superficial kind of beauty. when applied to women, ἀγλαΐη betrays the same set of nuances. the ‘beautiful- cheeked’ (καλλιπάρῃος) housemaid melantho is warned by odysseus that someday ‘you may lose all the beauty [ἀγλαΐην] in which now you surpass the other house- maids’. abusive, ungrateful and deceitful, melantho is one of the most detestable characters in the odyssey; conveyed with the noun ἀγλαΐη, her beauty is clearly only skin deep. this connotation is reaffirmed by the noun’s link with cosmetics. when eurynome encourages penelope to wash and anoint her cheeks before presenting herself to the suitors, penelope says that it is no use because ‘the gods destroyed … [her] beauty’ (ἀγλαΐην … θεοὶ … ὤλεσαν) when odysseus left for troy. so penelope believes she has lost the ἀγλαΐη, ‘the glamorous beauty’, she had twenty years ago, but thanks to athena she has enough κάλλος, ‘desirable beauty’, to weaken the suitors’ knees. for both penelope and melantho, moreover, ἀγλαΐη is represented as a quality one loses, perhaps suggesting the noun’s association with youthful good looks: just as penelope believes she has lost her ἀγλαΐη of twenty years ago, so melantho’s ἀγλαΐη may soon fade. in sum, ἀγλαΐη primarily denotes a superficial glamorous kind of beauty marked by a certain pageantry, which corresponds with the use of the word beauty in the modern cosmetics industry. sense of ‘excessive pride’ or, in the plural, ‘vanities’. conversely, at od. . – the association with pride takes a positive meaning: menelaus tells telemachus that ‘it is both an honour [κῦδος] and source of pride [ἀγλαΐη] and advantage [ὄνειαρ] to have a meal and then set off over the great bound- less earth’. on the interpretative difficulties of these lines, see a. heubeck and a. hoekstra, a commentary on homer’s odyssey. volume ii, books ix–xvi (oxford, ), . hom. il. . – , . – . hom. il. . – = . – . hom. od. . – . given this connotation, the appearance of ἀγλαΐη in connection with nireus makes perfect sense. he is ‘the son of aglaïē [Ἀγλαΐης] and charopos’ (hom. il. . ). the peculiar nature of nireus’ beauty is implied by his mother’s name which personifies the noun ἀγλαΐη: his characterization as aglaïē’s son underlines both his beauty—he is the ‘most beautiful’ (κάλλιστος) achaean after achilles—and its superficiality—for he is ‘weak’ and a leader of few. hom. od. . , . – . hom. od. . – . cf. hes. theog. – : Ἀγλαΐην … ὁπλοτάτην Χαρίτων. cf. later authors’ use of ἀγλαΐη to mean ‘festivity’, in the sense of elaborate and spectacular dis- play, e.g. hes. [sc.] ; pind. ol. . ; pyth. . . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core rather than one word for ‘beauty’ and one for ‘beautiful’, homer has three sets of alternatives which are conceptually interconnected yet distinguished by their various semantic and aesthetic idiosyncrasies: κάλλος and καλός; χάρις and χαρίεις; ἀγλαΐη and ἀγλαός. yet, homer’s terminology for beauty does not stop there for the simple reason that expressing beauty does not depend on an explicit word for ‘beauty’ or ‘beautiful’. ii. implicit expressions the homeric lexicon contains a variety of terms and formulaic expressions that convey beauty without one of the more obvious lexical suspects so far discussed. let us begin with the nouns ἄγαλμα, κόσμος and μορφή. derived from ἀγάλλομαι, the noun ἄγαλμα follows naturally from the preceding discussion of ἀγλαΐη and ἀγλαός. what an ἄγαλμα is varies considerably: a horse, an ivory cheekpiece, the trojan horse, a necklace, a brooch, and gold and woven goods are all ἀγάλματα in homer. what an ἄγαλμα does, however, remains consistent: as its etymology suggests, it is an object that is a source of simultaneous pride, pleasure and delight to its owner. in other words, an ἄγαλμα is defined by its pleasing effects, and this explains why for five of its eight occurrences in homer the noun describes gifts, both for humans and for gods—a notable similarity with the common application of ἀγλαός to δῶρα, ‘gifts’. it is clear, moreover, that the pleasing effects of ἀγάλματα are inseparable from their aesthetic properties. nestor employs a goldsmith to gild the horns of a sacrificial heifer for athena ‘in order that the goddess might look at the agalma and be pleased’ (ἵν’ ἄγαλμα θεὰ κεχάροιτο ἰδοῦσα). the gilded heifer is an ἄγαλμα because of the pleasure— signified by χαίρω, cognate with χάρις—it may give athena’s eyes and the honour and pride she may experience as its recipient. as gold beautifies the beast for the deity’s aesthetic pleasure, the passage recalls athena’s beautification of odysseus when she pours χάρις on him like a craftsman pouring gold on silver in the creation of ‘pleasing works’. the description of odysseus’ ‘shining brooch’, which penelope gave to him ‘to be an agalma’, similarly instantiates forms and affects common to other homeric terms and expressions for beauty. not just golden and radiant, it is also δαίδαλον, ‘cunningly wrought’, depicting a ‘dappled fawn’ (ποικίλον ἐλλόν), and inspires the ‘wonder’ of all onlookers (τὸ δὲ θαυμάζεσκον ἅπαντες). the beautiful visual properties of the on the relationship between ἄγαλμα, ἀγλαός and ἀγλαΐη, see j.w. day, archaic greek epigram and dedication: representation and reperformance (cambridge, ), – . see hom. il. . ; od. . , . , . , . , . , . , . . hom. od. . . hom. od. . – . on the relationship between ἄγαλμα and χάρις, see n. lanérès, ‘la notion d’agalma dans les inscriptions grecques, des origines à la fin du classicisme, métis ( ), – , at – . on beautifying the beast in greek sacrifice, see f.t. van straten, hiera kala: images of animal sacrifice in archaic and classical greece (leiden, ), – ; cf. f. naiden, ‘sacrifice’, in e. eidinow and j. kindt (edd.), the oxford handbook of ancient greek religion (oxford, ), – . hom. od. . – . hom. od. . – . hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core brooch are instrumental to its status as an ἄγαλμα, ‘an object of delight’, ‘a pride and joy’, for odysseus. it is noteworthy that the brooch is an ἄγαλμα specifically for odysseus, not his admiring onlookers. in other words, an ἄγαλμα is a possession, whether of gods or of humans. this sense is clear when homer envisages a woman who ‘stains ivory with crimson dye … to make a cheekpiece for horses; it is kept in a chamber, and many horsemen pray to wear it. but it is kept there as an agalma for the king, both an ornament [κόσμος] for a horse and an honour [κῦδος] for the rider’. the ἄγαλμα is an ‘ornament’, ‘adornment’ (κόσμος) for a horse by enhancing its attractiveness, and confers ‘honour’, ‘glory’ (κῦδος) on its owner because of its attractive appearance and the admiration it inspires. it is fair to say then that the noun ἄγαλμα makes its own peculiar contribution to homer’s terminology for beauty: it denotes an object that by virtue of its beautiful visual properties is a source of pride, pleasure and delight for its owner, and is therefore invested in the social dynamics of honour mediated by desirable material possessions. without this notion of ownership, the ἄγαλμα of the ivory cheekpiece would be sim- ply a κόσμος, an ‘ornament’, ‘adornment’, as it is for the horse. κόσμος, then, is some- thing that enhances physical attractiveness, as does hera’s κόσμος in her seduction of zeus. the scene of hera’s toilette is perhaps the most emphatic representation of any character’s beauty in homer. this is conveyed not just by the repetition of καλός four times in short succession—her skin, hair, veil and sandals are all ‘beautiful’— and the fact that ‘great beauty [χάρις] shone from’ her earrings but also by the appear- ance of some familiar physical properties: her hair, veil and feet are radiant; her dress is decorated with ‘many cunning embellishments’ (δαίδαλα πολλά); the pins fastening her dress are golden. the sum total of these beautiful adornments is πάντα … κόσμον, ‘all her finery’—fit for seducing and deceiving zeus, just as aphrodite’s ‘beautiful, golden’ and radiant κόσμος seduces anchises in her homeric hymn. the examples of hera and the horse suggest that κόσμος is more than conceptually contiguous with other terms and expressions for beauty: it denotes material adornment that has a beautifying effect. for the majority of its occurrences in homer, however, κόσμος is used in adverbial expressions to mean ‘in order’, either in a physical sense of orderly formation and arrangement, or in an abstract sense of what is right and proper. the semantic range of κόσμος, from ‘proper order’ to ‘adornment’, bears a telling resemblance to the semantic range of καλός, which also embraces everything from beautiful appearances to appropriate behaviour. this semantic parallel is cf. alcm. fr. . – . hom. il. . – . compare the role of beautiful objects in the customs of homeric guest-friendship. menelaus gives telemachus his ‘most beautiful’ (κάλλιστος) and ‘most valuable’ (τιμηέστατος) treasure—a sil- ver mixing-bowl with gold rims (hom. od. . – ); the object’s beauty is integral to its material and social value in managing a pleasing relationship of χάρις. cf. od. . – . cf. n. himmelmann, ‘the plastic arts in homeric society’, in w. childs (ed.), reading greek art: essays by nikolaus himmelmann (princeton, ), – , at – : ‘a remarkable aspect of the homeric work of art … [is] its role as a possession’. hom. il. . – . hom. il. . ; hom. hymn . – , . – . cf. hom. hymn . . e.g. hom. il. . , . ; od. . , . . in homer, the cognate verb κοσμέω is only used to mean ‘to order, arrange’; cf. hom. hymn . , where it used to mean ‘adorn’. cf. lfgre: s.v. καλός (b); j.d. mikalson, new aspects of religion in ancient athens: honors, authorities, esthetics, and society (leiden, ), – , who notes the mutual aesthetic signifi- cance of καλός and κόσμος in descriptions of religious ritual. beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core reaffirmed by their implicit assimilation in odysseus’ response to euryalus’ derisive comments. odysseus tells euryalus that he has ‘not spoken well’ (οὐ καλὸν ἔειπες), gives him a lecture on the different blessings of eloquence and physical appearance, then reasserts that euryalus has ‘spoken in no due order’, ‘out of order’ (εἰπὼν οὐ κατὰ κόσμον). like καλός, the semantic range of κόσμος echoes the slippery and complex relationship between what is beautiful in appearance and what is right, proper and good. such semantic range may suggest the slippage between these qualities, but poetic narrative problematizes their relationship, at least for human beauty: nireus is ‘most beautiful’ but also ‘weak’ and a leader of few. euryalus is another prime example of the potential dissonance between physical beauty and excellence of character. in his lecture to euryalus, odysseus imagines two hypothetical men: ‘one man is weaker in appearance [εἶδος ἀκιδνότερος], but god crowns his words with shapeliness [μορφήν]’; ‘the other is like the immortals in appearance [εἶδος … ἀλίγκιος ἀθανάτοισιν], but beauty [χάρις] does not crown his words’. euryalus is like the lat- ter, blessed in looks but deficient in mind and eloquence: ‘so too’, odysseus concedes, ‘your appearance is outstanding [εἶδος μὲν ἀριπρεπές] … but your mind is empty [ἀποφώλιος]’. the words of the second man lack ‘beauty’ (χάρις), unlike the words of the first man which possess μορφή. for its only other appearance in homer, the noun μορφή is again a quality of words: it signifies the ‘shapeliness’ of odysseus’ words according to alcinous. although in later use μορφή can mean simply ‘form’, ‘shape’, for both its appearances in homer it has a positive aesthetic sense: not the ‘form’ of words but ‘the beauty of their form’, their ‘shapeliness’. the use of μορφή and χάρις together, moreover, exemplifies a familiar trope in homer’s aesthetic terminology: the use of discrete but conceptually interconnected and mutually support- ive terms to convey beauty. the same is true for the expression of physical beauty in the passage: euryalus’ ‘outstanding appearance’ is assimilated with his hypothetical counterpart who is ‘like the immortals in appearance’. here, then, we have two more common homeric methods of expressing human beauty. we will return to divine analogy shortly. first, let us explore the use of phrases with the physical properties εἶδος, δέμας, μέγεθος and φυή. piqued by odysseus’ endless desire for his wife penelope, the nymph calypso points out that she can ‘claim to be no worse than her, neither in form nor in build’. calypso asserts her superior beauty according to a common homeric formula: by combining an adjective—‘worse’ (χερείων)—with a word or words denoting general aspects of phys- ical appearance—‘form’ (δέμας) and ‘build’ (φυή). in his reply, odysseus adopts the same idiom, adding two further terms to the list: he acknowledges that penelope is ‘weaker in appearance and size’ (εἶδος ἀκιδνοτέρη μέγεθός τ᾽). but odysseus’ desire ‘to go home’ and reunite with his wife exceeds the seductive allure of calypso’s hom. od. . , . . so, too, hera’s κόσμος is hardly good or proper in a moral sense (at least as far as zeus is concerned); it is her weapon of deception. on ‘the problem of female beauty’ in greek culture, see r. blondell, helen of troy: beauty, myth, devastation (oxford, ), – . hom. od. . – , . – . hom. od. . – . hom. od. . . cf. lfgre: s.v. μορφή. hom. od. . – . hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core physical beauty. much like his tearful response to demodocus’ song, odysseus’ per- sonal story defies the expected response to beauty, in this case the goddess’ superior appearance, size, form and build. these four physical properties provide the basic standards by which homeric individuals are physically differentiated: εἶδος (‘appearance’, ‘looks’); δέμας (‘form’, ‘shape’); μέγεθος (‘size’, ‘height’); φυή (‘form’, ‘build’). though inherently neutral terms, when combined with various adjectives like ‘better’ (ἀμείνων), ‘best’ (ἄριστος) and ‘admirable’ (ἀγητός), they are used to denote positive aspects of appearance. but is a ‘best appearance’ a beautiful one in homer? the potential ambiguity of such phrases is mitigated by their common appearance alongside other expressions for beauty. in iliad book , for instance, paris has a ‘beautiful appearance’ (καλὸν εἶδος), ‘glistens with beauty’ (κάλλεΐ τε στίλβων) and is ‘best in looks’ (εἶδος ἄριστε). perhaps the best example of how homer layers these various terms and expressions for beauty is in the episode with penelope and the suitors. enchanted by the sight of penelope endowed with ‘immortal kallos’, eurymachus exclaims: ‘you excel all women in appearance and height’ (περίεσσι γυναικῶν | εἶδός τε μέγεθός τε). yet, penelope rejects his praise with the same idiom she used to convey her loss of ἀγλαΐη: ‘eurymachus, the immortals destroyed my excellence in appearance and form [ἐμὴν ἀρετὴν εἶδός τε δέμας τε], when the argives made for ilium.’ in a single sequence, therefore, the poet uses four distinct yet overlapping expressions for penelope’s beauty. whether it is the moralizing tone of ‘excellence in appearance and form’, the relativizing formula of excelling ‘all women in appearance and height’, the erotic lure of κάλλος or the glamour of ἀγλαΐη, each expression brings its connotations to bear in this nuanced portrait of penelope’s beauty. in addition to this layering effect, phrases with εἶδος, δέμας, μέγεθος and φυή stand out as homer’s favourite way of defining relative beauty. more often than he employs a word for ‘beauty’ or ‘beautiful’, homer compares how beautiful people are in terms of their ‘appearance’, ‘form’, ‘height’ and ‘build’. penelope excels ‘all women in appearance and height’, just as calypso knows she must be no worse than penelope in ‘neither form nor build’. as the standard criteria by which people are physically differentiated in the homeric poems, it makes perfect sense that these four properties also provide the physical criteria by which the relative beauty of people (and gods) is hom. od. . – . on the absence of a single word for ‘body’ in homer, see j. redfield, ‘le sentiment homérique du moi’, le genre humain ( ), – ; j.-p. vernant, ‘mortals and immortals: the body of the divine’, in f.i. zeitlin (ed.), mortals and immortals: collected essays (princeton, ), – , at – . cf. εὐειδής (hom. il. . ), ‘of fair appearance’, ‘beautiful’; εὐφυής (il. . , . ), ‘shapely’. εἶδος sometimes appears unqualified in an implicitly positive sense, as when hector refers to paris’ ‘gifts of aphrodite’: ἥ τε κόμη τό τε εἶδος, ‘your hair and your looks’ (il. . – ). εἶδος is often translated therefore as ‘beauty’, e.g. blondell (n. ), . we should beware making this leap, however, because εἶδος can be combined with a negative adjective to express ugliness: dolon ‘was bad in appearance’ (εἶδος … ἔην κακός) (il. . ). hom. il. . , . – , . . cf. . , . . hom. od. . – . hom. od. . – . cf. od. . – . comparisons with καλλίων: hom. od. . ; with κάλλιστος: il. . , . , . ; with κάλλος: Ιl. . , . ; with ἀγλαΐη: od. . – . comparisons with εἶδος, δέμας, etc.: il. . – , . , etc. beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core assessed, calibrated and understood. the earliest evidence for greek beauty-contests reaffirms this tendency outside homeric epic: alcaeus refers to women on lesbos κριννόμεναι φύαν, ‘being judged in form’. likewise, in hesiod’s catalogue of women, phrases with εἶδος are a pervasive means of both expressing and relativizing beauty: this past age abounded with women ‘lovely in appearance’, who ‘rivalled the immortal goddesses in appearance’. as in the catalogue, so in homeric epic, the gods are paradigms of anthropomorphic beauty. calypso clearly articulates this assumption when she points out that ‘it would by no means be right for mortal women to rival immortal goddesses in form and appear- ance’. gods are more beautiful than humans, and it is for this reason that divine ana- logy provides a common method of expressing beauty. of course, not every comparison of a human to a god emphasizes beauty. exceptional strength, power and wits also assimilate humans to gods, but physical beauty has an important place in this catalogue of godlike attributes, as it represents the outstanding difference between human and divine appearance. generalized comparisons are prolific: phrases such as ‘godlike in appearance’ (θεοειδής), ‘resembling a god’ (θεῷ ἐναλίγκιος), ‘looking like the goddesses’ (ἐϊκυῖα θεῇσιν) and ‘in form like the immortals’ (δέμας ἀθανάτοισιν ὁμοῖος) emphasize both the beauty of homer’s heroes and heroines and their remarkable proximity with the gods. and just as these general comparisons highlight a defining feature of homer’s myth- ical world—the proximity of gods and heroes—so comparisons with specific deities highlight defining features of particular individuals at the same time as emphasizing their beauty. homer expresses nausicaa’s beauty in various ways: she is both ‘like the immortal goddesses in form and appearance’ (ἀθανάτῃσι φυὴν καὶ εἶδος ὁμοίη) and ‘has beauty from the gods’ (θεῶν ἄπο κάλλος). her lengthy comparison to artemis elaborates and refines the portrait of her beauty. she is likened to artemis roving the mountains in pursuit of wild beasts, accompanied by her nymphs: ‘high above them all [artemis] holds her head and brow, and easily is she recognized [ἀριγνώτη], though all [the nymphs] are beautiful [καλαί]. just so did the unmarried maiden [παρθένος ἀδμής] stand out amid her handmaids.’ nausicaa is distinguished by her height and beauty like artemis, whose appearance in this wild guise mirrors nausicaa’s premarital status, as she too is ἀδμής, ‘untamed’, ‘unmarried’. but the simile also suggests nausicaa’s desirability as a bride by highlighting her outstanding beauty. the analogy thus helps define nausicaa’s peculiar social position in the epic: unwed though ready for marriage. alc. fr. b. . on greek beauty contests, see f. gherchanoc, concours de beauté et beautés du corps en grèce ancienne: discourse et pratiques (bordeaux, ). e.g. hes. cat. . : κούρας πολυήρ]ατον εἶδος ἐχούσας; e.g. . : Φυλο[νόην θ᾿ ἣ εἶδος ἐρήριστ᾿ ἀθαν]άτηισι. cf. . , . , . . on female beauty in the catalogue, see r. osborne, ‘ordering women in hesiod’s catalogue’, in r. hunter (ed.), the hesiodic catalogue of women: constructions and reconstructions (cambridge, ), – . cf. hes. [sc.] – . hom. od. . – : ἐπεὶ οὔ πως οὐδὲ ἔοικεν | θνητὰς ἀθανάτῃσι δέμας καὶ εἶδος ἐρίζειν. on the similarity and difference between homeric gods and heroes, see j. griffin, homer on life and death (oxford, ), especially – . e.g. hom. il. . ; od. . . hom. od. . , . . hom. od. . – . for this aspect of nausicaa’s portrayal, see hom. od. . – , . – , . – , . – , . – , . – . hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core similarly, penelope’s appearance ‘like artemis or golden aphrodite’ tells us some- thing special about her. like artemis, she is a model of chaste female beauty, renowned for her fidelity in her husband’s twenty-year absence. but she is also desir- able like aphrodite, drawing a host of suitors to her door. in these specific divine analogies, homer draws on his audience’s knowledge of clearly differentiated divinities to enrich his mortal characters at the same time as illustrating their beauty. like all homeric terms and expressions for beauty, therefore, divine analogy is distinguished by certain uses, connotations and implications which the poet harnesses for particular effects. nowhere is this clearer than when priam and achilles are reconciled through their common mortality and suffering, which defines humans in contrast to the gods, who, achilles says, ‘are free from sorrow’. yet, even in this moment of intense grief, achilles and priam are able to appreciate one another’s beauty: ‘priam wondered [θαύμαζ’] at achilles, so big and such as he was; for he was like the gods to look at [θεοῖσι γὰρ ἄντα ἐῴκει]. and achilles wondered [θαύμαζεν] at dardanian priam … and when they had taken pleasure [τάρπησαν] in looking at one another, the old man priam, godlike in appearance [θεοειδής], spoke to him.’ at once indicative of his characteristic sensitivity to beauty, the passage demonstrates how homer creatively exploits the particular connotations of divine analogy as a way to express beauty. both achilles and priam may look beautiful like gods, but this physical similarity only serves to underscore their essential difference from the gods which has framed their reconciliation. for unlike gods, suffering and death await them both; yet it is from this sad fact that compassion between two mortal enemies may emerge. the divine assimilation of achilles and priam simultaneously conveys their beauty and intensifies the poignancy of their realization of common suffering and humanity. iii. physical properties and affects in addition to a cluster of words for ‘beauty’ and ‘beautiful’, therefore, the homeric lexi- con contains a variety of implicit expressions of beauty. and like the various words for ‘beauty’ and ‘beautiful’, these implicit expressions are conceptually interconnected but marked by certain individual uses and connotations. testimony to that interconnection is their common application to single objects: homer frequently layers multiple terms and expressions for beauty, both for emphasis and for variety. the particular connotations of these various terms and phrases also allow the poet to enrich his representations of beauty with great subtlety and depth of nuance. all very well, the reader may think, but is it not problematic to bring diverse ancient terms and phrases together under the modern conceptual umbrella of beauty? does that not smack of anachronism? to group these diverse terms and phrases together is not to hom. od. . , . . cf. j. russo, m. fernàndez-galiano and a. heubeck, a commentary on homer’s odyssey, volume iii, books xvii–xxiv (oxford, ), . see hom. od. . – , . – , . – . see hom. od. . – , especially . – . cf. hom. od. . – . hom. il. . – . hom. il. . – . on the sensitivity to beauty in this passage and its thematic significance, see j. griffin, homer (oxford, ), . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core efface their differences or force them into a modern mould of beauty. rather, it is to show that they share conceptual common-ground both with each other and, in various ways, with modern ideas about beauty, however elusive and mutable. what we are dealing with is a series of relationships: relationships between ancient terms, and relationships between ancient and modern ideas. as for the latter, their inevitable discrepancies make these ‘beautiful things’ even more ‘difficult’ for modern interpreters, surrounded as they are by potential pitfalls of anachronism. but it is precisely this complex relationship between ancient and modern aesthetic ideas—their simultaneous similarity and difference—that makes them such intriguing and valuable objects of enquiry. as for the relationships between ancient terms, these are in part discernible in their mutual association with certain physical prop- erties and affects that have recurred throughout this paper. in other words, the expression of beauty in homer is tied to a spectrum of affects—notably desire, wonder, admiration and pleasure—and a catalogue of physical properties—notably radiance, bigness, skilful manufacture and precious materiality, especially gold and silver. the final part of this paper argues that such physical properties and affects can in themselves evoke a sense of beauty. divine analogy works in a similar way: the representation of beauty by divine comparison is entirely oblique; the audience infers the mortal analogue’s beauty because gods are known to be exceptionally beautiful. likewise, their connection with beauty is such that at times these physical properties and affects can convey beauty too. a simple example is the epithet ‘white-armed’ (λευκώλενος) for women and goddesses. that the epithet suggests female beauty is indicated by athena’s beautification of penelope, when she makes her ‘bigger and fuller in appearance and whiter than sawn ivory’. of course, it does not follow that everything white is beautiful; it is the aesthetic significance of whiteness for women in particular that gives the epithet its meaning. but this is a quite specific case, and for others the sense may be less clear. just because, say, bigness and wonder are often associated with beauty does not mean every- thing big and wonderful is beautiful: polyphemos ‘was a massive wonder’ (θαῦμ’ ἐτέτυκτο πελώριον) but hardly beautiful. ‘wonder’ in homer is not an exclusive response to beauty; surprising and lamentable things are also ‘wonders’, and it seems that for polyphemos the latter sense prevails. sensitivity to context is therefore essen- tial. for in another instance a ‘wonder’ appears synonymous with ‘beauty’: neleus’ daughter, pero, was ‘a wonder to mortals, whom all the men in the neighbourhood courted’ (θαῦμα βροτοῖσι, | τὴν πάντες μνώοντο περικτίται), much like her mother, ‘most beautiful [περικαλλέα] chloris, whom neleus married on account of her beauty [κάλλος]’. in the context of courtship, then, the ‘wonder’ inspired by pero is indica- tive of her beauty. similarly, when eros and wonder combine in the representation of see destrée and murray (n. ), – ; m. squire, ‘conceptualizing the (visual) “arts”’, in p. destrée and p. murray (edd.), a companion to ancient aesthetics (chichester, ), – . e.g. hom. il. . , . , etc.; od. . , . , etc. hom. od. . – . cf. il. . ; od. . . see m. treu, von homer zur lyrik (münchen, ), – . hom. od. . ; cf. . – . for surprising and lamentable wonders, see hom. il. . , . ; od. . . on greek aesthetics of wonder, see prier (n. ); neer (n. ); c. hunzinger, ‘wonder’, in p. destrée and p. murray (edd.), a companion to ancient aesthetics (chichester, ), – . hom. od. . – , . – . hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core aphrodite’s ‘lovely/desirable clothes, a wonder to behold’ (εἵματα … ἐπήρατα, θαῦμα ἰδέσθαι), we can be fairly confident that this expresses their beauty. desire may be a common response to beauty, but this does not mean that every appearance of a word for ‘lovely’ or ‘desirable’—such as ἐπήρατος, ἐρατεινός, πολυήρατος and ἱμερόεις—evokes beauty. but it is important to acknowledge that on occasion they do—like aphrodite’s ‘lovely clothes’—and that they therefore have a place in homer’s terminology for beauty alongside words like χάρις and ἄγαλμα that also have the effect of beauty (pleasure and delight respectively) written into their semantics. the characterization of hermione as helen’s ‘desirable daughter’ (παῖδ’ ἐρατεινήν), for instance, underlines the peculiar nature of her beauty, which is also implied by her assimilation to ‘golden aphrodite’. beauty and desirability often appear as two sides of the same coin in homer. in some contexts, therefore, the former can be inferred from the latter: the ‘desirable dance’ (χορὸν ἱμερόεντα) of the charites testifies to its beauty, just as in alcman’s choral lyric, the erotic impact of astymeloisa is testimony to hers. the appearance of hagesichora in alcman’s first partheneion echoes another familiar homeric topos of aestheticization: hagesichora’s hair ‘blooms like undefiled gold, her face like silver’ (ἐπανθεῖ | χρυσὸς [ὡ]ς ἀκήρατος· | τό τ’ ἀργύριον πρόσωπον). so, too, rhesus’ ‘chariot well worked [εὖ ἤσκηται] with gold and silver’ suggests its beauty by virtue of the aesthetic connotations of gold, silver and skilful manufacture. his ‘golden, massive armour, a wonder to behold’ (τεύχεα δὲ χρύσεια πελώρια θαῦμα ἰδέσθαι) demonstrates the same technique: the association of gold, bigness and wonder with material beauty is such that their depiction together aestheticizes rhesus’ armour. dolon’s comment that it is only appropriate for gods to wear such armour underscores this impression; such heights of beauty and magnificence are a divine preserve. no wonder, then, that gold is the divine material par excellence. but more than any other deity, gold is associated with aphrodite: her most common homeric epithet is ‘golden’. is it coincidence that she is also distinguished by her beauty? and it is perhaps down to more than chance or the demands of versification that whenever she is compared with mortal women to emphasize their beauty, she appears as ‘golden aphrodite’: hermione had ‘the looks of golden aphrodite’ (ἣ εἶδος ἔχε χρυσῆς Ἀφροδίτης), while achilles would not marry agamemnon’s daughter ‘even if she rivalled golden aphrodite in beauty’ (οὐδ’ εἰ χρυσείῃ Ἀφροδίτῃ κάλλος ἐρίζοι). hom. od. . . hom. od. . – . cf. il. . . see especially section on κάλλος above and konstan (n. [ ] and [ ]). hom. od. . . cf. il. . – , . . see alcm. fr. . – . cf. hes. theog. – ; sappho, fr. ; thgn. ; pind. fr. ; pl. phdr. a– b. on eroticization as a formulaic means of expressing beauty in alcman and sappho, see g. most, ‘greek lyric poets’, in t.j. luce (ed.), ancient writers: greece and rome (new york, ), – , especially ; a. lardinois, ‘keening sappho: female speech genres in sappho’s poetry’, in a. lardinois and l. mcclure (edd.), making silence speak: women’s voices in greek literature and society (princeton and oxford, ), – . alcm. fr. . – . cf. alcm. ( col. ii); hom. il. . – . hom. il. . . hom. il. . . see e.g. hom. il. . – , . – , . – . ‘golden aphrodite’ appears eleven times. hom. od. . ; il. . . cf. il. . , . ; od. . , . . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core as far as physical properties are concerned, only radiance can claim a stronger connection with homeric beauty than gold: the beauties of κάλλος and χάρις are themselves forms of radiance. when gold and radiance appear together, therefore, the inference of beauty is hard to resist, let alone if skilful craftsmanship is added to the list: ‘expertly crafted … golden, strung with amber beads, like the sun’ (πολυδαίδαλον … χρύσεον, ἠλέκτροισιν ἐερμένον, ἠέλιον ὥς)—the physical proper- ties of the necklace eurymachus gives penelope are all evocative of its beauty. for the aestheticization of odysseus’ tunic, by contrast, radiance combines with a common affect of beauty—aesthetic admiration—denoted by the verb θηέομαι: his ‘glittering tunic … was soft, and radiant like the sun; many women marvelled at it’ (χιτῶν’ … σιγαλόεντα … ἔην μαλακός, λαμπρὸς δ’ ἦν ἠέλιος ὥς. | ἦ μὲν πολλαί γ’ αὐτὸν ἐθηήσαντο γυναῖκες). radiance is fundamental to beauty in homer, as it is in much archaic poetry: aphrodite’s ‘immortal beauty’ (κάλλος … ἄμβροτον) shines from her cheeks in her homeric hymn; to ‘have the sparkle of the charites’ (Χαρίτων ἀμαρύγματ᾿ ἔχο[υσαν) is a recurrent formula for female beauty in the catalogue of women; the ‘bright sparkle’ (κἀμάρυχμα λαμπρόν) of anactoria’s face is a mark of the beauty sappho’s speaker loves and longs for. so where do we draw the line? does every- thing radiant in homer connote beauty? achilles is a case in point. the sight of achilles, radiant in his armour like the star orion—the ‘brightest’ (λαμπρότατος) star, an ‘evil sign’ (κακὸν … σῆμα) to mortals— terrifies priam, who fears for his son’s life. achilles’ ominous radiance recalls athena’s descent from heaven ‘like a star … a shining portent [τέρας … λαμπρόν] to sailors or a large army of people’. and when hector sees achilles in his brazen armour shining ‘like the light of blazing fire or the rising sun’, he is overcome with ‘trembling’; the death and destruction presaged by achilles’ godlike radiance is aimed squarely at him. ominous, godlike and terrifying, achilles’ radiance is a far cry from the seductive sight of paris or odysseus ‘glistening with beauty’. perhaps it would be safer, then, to set achilles’ brightness outside the realm of homeric beauty. and yet the culmination in this series of radiant apparitions should make us think twice. at precisely the moment when he is at his most deadly and terrifying—in his final encounter with hector—homer emphasizes achilles’ radiant beauty in arms: his shield is ‘beautiful, cunningly wrought’ (καλὸν δαιδάλεον); the plumes of his see n. . hom. od. . – . hom. od. . – . cf. od. . – ; anac. fr. . see n. . hom. hymn . – ; cf. . – ; hom. hymn . – . hes. cat. . , . , . , a. . sappho, fr. . . cf. hdt. . . – : tellus had τελευτὴ τοῦ βίου λαμπροτάτη and ἀπέθανε κάλλιστα. hom. il. . – . cf. il. . – , . – , . – . see c. moulton, similes in the homeric poems (göttingen, ), – , – . hom. il. . – . for more divine radiance, see e.g. hom. il. . – , . ; od. . – ; s. constantinidou, ‘the light imagery of divine manifestation in homer’, in m. christopoulos, e.d. karakantza, o. levaniouk (edd.), light and darkness in ancient greek myth and religion (lanham, ), – . hom. il. . – . hom. il. . ; od. . . the first in this series, which charts achilles’ return to the fighting, is at hom. il. . – , where athena manifests a golden radiant cloud around achilles’ head. hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core ‘shining helmet’ are ‘beautiful … golden’ (καλαί … χρύσεαι); most striking of all, his spear, with which he is about to kill hector, is ‘like the evening star, the most beautiful star in heaven’ (οἷος δ’ ἀστὴρ … ἕσπερος, ὃς κάλλιστος ἐν οὐρανῷ … ἀστήρ). reminiscent of demeter’s and aphrodite’s epiphanies in their homeric hymns, achilles’ radiance here is godlike, terrifying and beautiful—no less than sublime. the passage therefore invites the possibility that his radiant manifestations leading up to this climactic moment similarly connote a sense of terrifying divine beauty. achilles is a good example, then, of the challenges we face in attempting to access that peculiarly homeric sense of beauty. bound to a culture of visual theology foreign to our own, the representation of achilles’ terrifying divine beauty may seem alien to mod- ern aesthetic expectations. more than that, this series of apparitions highlights how the lines between what is radiant and what is beautiful are not always clearly drawn. nor are those between what is beautiful and what is wonderful, desirable or admirable. sensitivity to context is therefore essential for determining where the outer boundaries of homeric beauty lie. they may be more fluid and less clear than perhaps we would like, but this kind of complication does not mean that we should ignore all those cases where things radiant, wonderful, desirable or admirable are expressive of beauty. for however hermeneutically challenging, they have an integral place in the broad semantic field of homeric beauty. when the common physical properties and affects of homeric beauty converge, then we are on firmer ground. the choral scene of boys and girls on achilles’ shield offers a well-known example. the rare use of the verb ποικίλλω to signify hephaestus’ skilful and intricate manufacture of the image; the radiance of the boys’ ‘tunics glistening with oil’ (στίλβοντας ἐλαίῳ); their gold and silver daggers and baldrics; the ‘beautiful garlands’ (καλὰς στεφάνας) of the girls; the description of the audience ‘taking pleasure in the desirable chorus’ (ἱμερόεντα χορὸν … τερπόμενοι): the aesthetic connotations of these physical properties and affects work together to conjure an atmosphere of choral beauty. hom. il. . – . cf. hom. hymn . – ; hom. hymn . – . on the relation between the beautiful and the sublime in antiquity, see j.i. porter, ‘the sublime’, in p. destrée and p. murray (edd.), a companion to ancient aesthetics (chichester, ), – , at ; j.i. porter, the sublime in antiquity (cambridge, ), passim especially – ; see – on sublimity and divinity in homer. on visual theology in archaic greece, see vernant (n. ); v. platt, facing the gods: epiphany and representation in graeco-roman art, literature and religion (cambridge, ), especially – ; g. petridou, divine epiphany in greek literature and culture (oxford, ), especially – . cf. pl. hp. mai. e, where socrates comes to appreciate the proverb χαλεπὰ τὰ καλά after failing to define clearly the boundaries of καλός. cf. e. burke, a philosophical enquiry into the origin of our ideas of the sublime and beautiful (london, ), : ‘a clear idea is … another name for a little idea’. cf. hom. od. . – , . – , where the beauty of menelaus’ palace is conveyed by an abundance of gold, silver, electrum, ivory and radiance that inspire telemachus’ aesthetic admiration, wonder, awe and delight. hom. il. . – . note the description of the maidens as ἀλφεσίβοιαι ( . ), ‘bringing in oxen’, in the sense of ‘who yield their parents many oxen as presents from their suitors’, i.e. ‘much- courted’ (lsj). since beauty and skilful handiwork are the two outstanding qualities for which homeric women are courted, it seems that this adjective joins the list of implicit expressions of beauty. cf. il. . – , . – , . – ; od. . – , . – . on the visual aesthetics of this scene, see j. carruesco, ‘choral performance and geometric patterns in epic poetry and iconographic representations’, in v. cazzato and a. lardinois (edd.), the look of lyric: greek song and the visual (leiden and boston, ), – , at – . beauty in the iliad and the odyssey of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core in short, the common ingredients of homeric beauty—its physical properties and affects—have an aestheticizing power of their own. this has two important consequences for our understanding of beauty in homer. the first effect is a significant expansion of the semantic field of homeric beauty; the second, more challenging effect is that homeric beauty appears more nebulous, therefore underlining the necessity of attentiveness to context and contingency in clarifying ‘the shade, the fine distinction’ of aesthetic and semantic meaning. the terminology for beauty in the iliad and the odyssey is profoundly rich: the expression of beauty is bound to a plethora of terms and phrases, physical properties and affects. any reader of homer will know that hardly ten verses go by without the appearance of one or other of these words or phrases. it is true that there is a danger in over-expanding the reach of beauty; the challenge for us is to be sensitive to ancient modes of aesthetic expression, to interrogate their relationships with one another, and to pursue their consequences for understanding ideas about beauty foreign to our own. for there is also a danger in shying away from beauty’s potential vastness and complexity in homer. the poet envisages a world where beauty matters: the aestheticization of every- thing from people and gods to household objects and natural phenomena is an essential element of what elevates homer’s mythical past above and beyond the historical present of the poem’s performance and reception. hugo shakeshaftchrist church, oxford hugoshakeshaft @gmail.com charles.shakeshaft@chch.ox.ac.uk hugo shakeshaft of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms mailto:hugoshakeshaft @gmail.com mailto:charles.shakeshaft@chch.ox.ac.uk https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core the terminology for beauty in the iliad and the odyssey ‘beauty and ‘beautiful implicit expressions physical properties and affects untitled research watch | cancer discovery�july www.aacrjournals.org major finding: fcγriiia on macrophages and fcγriia on dendritic cells mediate adcc and vaccinal effects, respectively. concept: long-term mab-dependent immune responses require expression of fcγrs on cd c+ cells. impact: antibody engagement of both fcγriiia and fcγriia is required for maximal antitumor responses. antibodies fcgriiia and fcgriia engagement mediates antitumor cellular immunity passive delivery of antitumor mabs has been shown to promote rapid tumor cell death via transient induction of fc-receptor for igg (fcγr)– mediated antibody-dependent cellular cytotoxic- ity (adcc), which is determined by the relative binding affi nity of antibodies for activating and inhibitory fcγr receptors on effector cell sur- faces. in addition, antitumor mab therapy has also led to durable antitumor cellular immune responses in some patients, prompting dilillo and ravetch to study the mechanisms that underlie this long-term vaccinal effect. in a murine lymphoma model expressing the tumor neoantigen human cd (hcd ), treatment with the murine igg a isotype anti-hcd mab led to rapid clearance of lym- phoma cells via fcγr-mediated adcc, as well as sustained antitumor immune responses when mice were subsequently rechallenged with tumor cells that expressed hcd , but not cells lacking hcd expression. mechanistically, cd c+ cell–specifi c deletion of the activating receptor mfcγriv revealed that expression of mfcγriv was required to gen- erate long-term mab-stimulated vaccinal effects, but was dispensable for adcc-mediated tumor cell kill- ing. in order to bypass interspecies differences and assess the individual contributions of hfcγrs in generating mab-induced antitumor responses, fcγr-humanized mice expressing hfcγrs in the absence of mfcγrs were treated with higg anti- hcd variants engineered to selectively engage hfcγriiia, hfcγriia, or both hfcγriiia and hfcγriia. engagement of hfcγriiia, but not hfcγriia, was necessary and suf fi cient to promote adcc-mediated primary tumor cell clearance via clodronate liposome– sensitive macrophages. in contrast, however, long-term vac- cinal effects required hfcγriia expressed by dendritic cells. together, this work highlights the role of differential fcγr engagement in primary and long-term mab-mediated anti- tumor immune responses and suggests that targeting both fcγriiia and fcγriia may be required for maximal clinical benefi t of antitumor antibodies. ■ dilillo dj, ravetch jv. differential fc-receptor engagement drives an anti-tumor vaccinal effect. cell ; : – . major finding: osteosarcoma driver genes are enriched in the erbb, pi k–akt–mtor, mapk, and axon guidance pathways. concept: a forward genetic screen identified genes that accelerate pri- mary and metastatic osteosarcoma. impact: lineage tracing using common insertion sites reveals multiple patterns of metastatic spread. osteosarcoma a sleeping beauty screen highlights cancer drivers in osteosarcoma osteosarcoma is a common primary bone cancer with high metastatic potential. however, characterization of can- cer driver genes and potential therapeutic targets has been limited due to the highly heterogeneous and genomically unstable nature of osteosarcoma tumors. to identify genes that are involved in driving osteosarcoma, moriarity and col- leagues performed a sleeping beauty (sb) transposon-based forward genetic screen in mice harboring wild-type (sbmut) or mutant trp (trp -sbmut). sb mutagenesis promoted the formation of osteosarcomas that faithfully recapitulated the human disease and accelerated tumor formation in trp - mutant mice. analysis of common insertion sites (cis) from trp -sbmut and sbmut osteosarcomas identifi ed known osteosarcoma-associated genes, as well as putative proto-oncogenes and potential tumor suppressor genes, including nf and pten, which were observed in both genetic backgrounds. pathway analysis highlighted an enrichment of genes involved in the pi k–akt–mtor, mapk, and erbb signaling cascades, as well as mutations in upstream regula- tors of cis-associated genes, including mirnas that have been previously implicated in osteosarcoma. comparison of cis-associated gene expression, genomic alterations, and methylation across human osteosarcoma samples revealed that a signifi cant proportion of candidate genes was altered in tumor samples compared with normal tissue. functional validation of cis-associated genes reinforced the notion that loss of pten and trp cooperatively accelerate osteo- sarcomagenesis in mice and confi rmed that overexpression of the axon guidance genes sema d and sema d in human osteosarcoma cells was suffi cient to promote anchorage- independent growth and xenograft formation via activation of the pi k and mapk pathways. furthermore, analysis of metastases identifi ed cis-associated candidate metastasis driver genes and revealed multiple patterns of metastatic spread, including both parallel and clonal evolu- tion. together, these data demonstrate that forward genetic screens represent a useful tool to identify cancer driver genes in tumors with high genetic variability and highlight onco- genic pathways that may be targetable in osteosarcoma. ■ moriarity bs, otto gm, rahrmann ep, rathe sk, wolf nk, weg mt, et al. a sleeping beauty forward genetic screen identifi es new genes and pathways driving osteosarcoma development and metasta- sis. nat genet ; : – . on april , . © american association for cancer research. cancerdiscovery.aacrjournals.org downloaded from published onlinefirst may , ; doi: . / - .cd-rw - http://cancerdiscovery.aacrjournals.org/ ; : . published onlinefirst may , .cancer discovery osteosarcoma screen highlights cancer drivers insleeping beautya updated version . / - .cd-rw - doi: access the most recent version of this article at: e-mail alerts related to this article or journal.sign up to receive free email-alerts subscriptions reprints and .pubs@aacr.org to order reprints of this article or to subscribe to the journal, contact the aacr publications department at permissions rightslink site. click on "request permissions" which will take you to the copyright clearance center's (ccc) .http://cancerdiscovery.aacrjournals.org/content/ / / . to request permission to re-use all or part of this article, use this link on april , . © american association for cancer research. cancerdiscovery.aacrjournals.org downloaded from published onlinefirst may , ; doi: . / - .cd-rw - http://cancerdiscovery.aacrjournals.org/lookup/doi/ . / - .cd-rw - http://cancerdiscovery.aacrjournals.org/cgi/alerts mailto:pubs@aacr.org http://cancerdiscovery.aacrjournals.org/content/ / / . http://cancerdiscovery.aacrjournals.org/ c:\doc\beauty contest\belief&information_nber_ .wpd to appear in the journal of mathematical economics, beauty contests under private information and diverse beliefs: how different? by mordecai kurz, stanford university august , abstract: the paper contrasts theories that explain diverse belief by asymmetric private information (in short pi) with theories which postulate agents use subjective heterogenous beliefs (in short hb). we focus on problems where agents forecast aggregates such as profit rate of the s&p and our model is similar to the one used in the literature on asset pricing (e.g. brown and jennings ( ), grundy and mcnichols ( ), allen, morris and shin ( )). we first argue there is no a-priori conceptual basis to assuming pi about economic aggregates. since pi is not observed, models with pi offer no testable hypotheses, making it possible to prove anything with pi. in contrast, agents with hb reveal their forecasts hence data on market belief is used to test hypotheses of hb. we show the common knowledge assumptions of the pi theory are implausible. the theories differ on four main analytical issues. ( ) the pricing theory under pi implies prices have infinite memory and at each t depend upon unobservable variables. in contrast, under hb prices have finite memory and depend only upon observable variables. ( ) the “beauty contest” implications of the two are different. under pi today’s price depends upon today’s market belief about tomorrow’s mean belief about “fundamental” variables. under hb it depends upon today’s market belief about tomorrow’s market beliefs. tomorrow’s beliefs are, in part, beliefs about future beliefs and are often mistaken. market forecast mistakes are key to beauty contests, and are a central cause of market uncertainty called “endogenous uncertainty.” ( ) contrary to pi, theories with hb have wide empirical implications which are testable with available data. ( ) pi theories assume unobserved data and hence do not restrict behavior, while rationality conditions impose restrictions on any hb theory. we explain the tight restrictions on the model’s parameters imposed by the theory of rational beliefs. jel classification: d , d , d , g , g , e . keywords: private information; bayesian learning; updating beliefs; heterogenous beliefs; asset pricing; rational beliefs. for correspondence: mordecai kurz, joan kenney professor of economics department of economics, landau building stanford university stanford, ca. - email: mordecai@stanford.ed this research was supported by a grant of the smith richardson foundation to the stanford institute for economic policy research (siepr). the author thanks ken judd, stephen morris, maurizio motolese, ho-mou wu, min fan and john o’leary for helpful discussions of the ideas in this paper. department of economics, serra street at galvez, stanford university, stanford, ca. - , usa beauty contests under private information and diverse beliefs: how different by mordecai kurz, stanford university august , diversity of belief is an empirical fact. a large and growing body of work has used this diversity to explain various market phenomena, and there are two theories inspired by it. one follows the harsanyii doctrine which views people as bayesian decision makers who hold the same probability belief but who have asymmetric private information which they use in forecasting. examples of papers that are applicable here includes phelps ( ), lucas ( ), diamond and verrecchia ( ), singleton ( ), brown and jennings ( ), grundy and mcnichols ( ), wang ( ), he and wang ( ), hellwig ( ), judd and bernardo ( ), ( ), woodford ( ), allen, morris and shin ( ) and others. an alternative view holds that there is nothing to justify a common prior and heterogeneity of probability models is inevitable in a complex world. moreover, agents clearly do not have and do not use private information to forecast aggregates such as the s&p , gnp growth rate, exchange rates, inflation or interest rates, yet there is a vast diversity of such forecasts. a sample of papers which use this approach includes harrison and kreps ( ), varian ( ), ( ), harris and raviv ( ), detemple and murthy ( ), kurz ( ), ( a), kurz and motolese ( ), kurz jin and motolese ( a), ( b), motolese ( ), ( ), nielsen ( ),( ), wu and guo ( ), ( ). in particular, kurz’s ( ), ( a) theory of belief diversity stresses the impossibility of perfect learning. it holds that our environment is non-stationary with technological and institutional changes occurring faster than we can learn them. but then, how different are these two theories of belief diversity? what are the differences in their theoretical and empirical implications? this paper explores the economic structure of asset pricing theories under private information (in short, pi) compared with the structure of heterogenous beliefs approach (in short, hb), aiming to highlights the different theoretical and empirical implications of the two theories. to that end we keep the formalism down to a minimum, focusing on ideas and concepts. our discussion is confined to theories where optimizing agents forecast aggregates such as future s&p returns, exchange rates, interest rates, gdp growth etc. we do not address the problem of forecasting future conditions of individual firms or establishments. our main conclusions are that models with pi are not appropriate to the problem of forecasting economic aggregates and offer contrived solutions. on the other hand, theories where agents have diverse beliefs and use diverse models constitute a natural setting for problems of this type. we argue that pi models have virtually no empirical implications and hence with private information one can prove almost anything. in contras, models with hb have clear empirical implications and testable hypotheses since market beliefs are observable. to explore the key ideas we first outline a simple model used to study asset pricing with private information. in section we adapt the model to an environment with hb but without private information. after fully developing the equilibrium asset pricing theory under hb we compare in section the results to those obtained under private information. we explore in section . the restrictions on beliefs proposed by the theory of rational beliefs (see kurz ( ), ( a)). . asymmetric information and asset pricing the model reviewed here is an adaptation of the short lived trader model used by brown and jennings ( ), grundy and mcnichols ( ), allen, morris and shin ( ) and others. specifying the model will also provide us with terminology and notation used throughout the paper. there is a unit mass of traders, indexed by the [ , ] interval and only one homogenous aggregate asset (e.g. s&p index fund) with unknown intrinsic value q. the economy is static with one period divided into three dates (no discounting): in dates traders first receive a public and private signals about the asset value and then they trade. in date they trade again. in date (or end of date ) uncertainty is resolved, the true liquidation value q of the asset is revealed and traders receive this value for their holdings. the initial information of traders is that q is distributed normally with e(q) = y and variance . at date each trader also observes a private signal about q, α x i ' q % εi where are, independently normally distributed across all i with mean and variance . since theseεi β facts are common knowledge, agents know that the true unknown value q is “in the market” at all time since by the law of large numbers the mean of all private signals is the future value q. all have the same cara utility over wealth w, with constant absolute coefficient of risk aversion. they maximize expected utility where . trader i starts withu(w i) ' &e &(w i /τ) w i ' s i p %d i ( p &p )%d i ( q&p ) si units of the aggregate asset and can borrow at zero interest to finance trading in it. are i’s( d i , d i ) demands in the first and second rounds and are market prices in the two rounds. aggregate( p , p ) supplies (s , s ) of ownership shares traded in each of the rounds are random, unobserved and normally distributed. this noise is crucial since it ensures that traders cannot deduce from prices the true value of q. in a noisy rational expectations equilibrium (in short, ree) traders maximize expected utility while markets clear after traders deduce from prices all possible information. indeed, brown and jennings ( ) show equilibrium price at date is ( a) p ' κ ( λ y % μ q & s ) and since s is normally distributed p is also normally distributed. ( a) shows that since q and s are both unknown, prices are not fully revealing. since over trading dates q is fixed, more rounds of trading generate more price data from which traders deduce added information about q. but with additional supply shocks the inference problem becomes more complicated. that is, at date the price p contains more information about q but it depends upon two unobserved noise shocks (s , s ). hence, as in brown and jennings ( ), the price function takes the form ( b) .p ' κ̂ ( λ̂ y % μ̂ q & s % ψs ) since the realized noise s is not known at date , traders condition on the known price p to infer the information about s . they thus use a date price function which takes an equivalent form .p ' κ ( λ y % μ q & s % ξ p ) using ( a) equivalence implies that denoteκ 'κ̂ , λ ' (λ̂ %λ ψ) , μ ' (μ̂ %μ ψ) and ξ ' & ψ κ . by the information of i in the two rounds. the linearity of the equilibrium price map implies( h i , h i ) that the payoff is normally distributed. brown and jennings ( ) then show in appendix a that there exist constants determined by the covariance matrix of the model’s random variables such( g , g ) that the demand functions of trader i are ( a) .d i ( p ) ' τ var i (q | h i ) [ e i(q | h i ) & p ] ( b) .d i ( p ) ' τ g [ e i(p | h i ) & p ] % ( g & g ) g [e i ( d i | h i )] it is typically assumed that independent of i. the second term in ( b) is thevar i (q | h i ) ' σ q “hedging demand” arising from risk perception of traders at date about price change at date . the hedging demand in a noisy ree complicates the inference problem and raises problems regarding the existence of equilibrium. as a result, most writers ignore this demand and study the myopic-investor economy. this concept is framed by regarding traders as long or short lived. a “short lived” trader lives one period only. he first trades in date , gains utility from p and leaves the economy. he is replaced by a new short lived trader who knows the information of the first trader but trades in date and gains utility from the revealed q. neither trader has a hedging demand. a “long lived” trader lives through both periods, trades in dates and hence has a hedging demand. it is then common to ignore the second term in ( b), average on i, equate to supply and conclude that ( c) , .p ' ē ( q ) & σ q τ ( s % s ) p ' ē ( p ) & g τ s is date average market forecast of q and is average market forecast of . in thisē ( q ) ē ( p ) p case and it is assumed this variance is independent of i.g ' var i ( p ) ( a)-( b) depend only upon the condition that prices are normally distributed but not upon any private information assumption. hence, the difference between the two theories on which we focus in this paper result from differences between their implications to the conditional expectations in ( a)- ( b). for example, ( a) shows p depend upon date expectations which are updated based on the information deduced from p and p . this is different from date information which consists of public signal, private signals and inference from p . allen, morris and shin ( ) present in their appendix a computations of the closed form solution. to get an idea of the inference involved we review the steps they take. what does a trader learn in round ? given prior belief trader i q-n( y , α ) observes . since all he infers from date price is thatp 'κ ( λ y%μ q&s ) s -n( , /γ ) . κ μ ( p & κ λ y ) ' q& s μ - n ( q , /(μ γ ) ) but now, his added piece of information is the private signal , . using ax i ' θ % εi εi-n( , β ) standard bayesian inference from these three sources, his posterior belief becomes ( a) e i( q | h i ) ' αy%βx i %μ γ κ μ ( p &κ λ y) α % β % μ γ ' (α&μ γ λ ) y%βx i % μ γ κ p α % β % μ γ ( b) with precision .α % β % μ γ averaging ( a) over the population we can see that the average market forecast at date is then .ē ( q | h ) ' ( α&μ γ λ ) y%βq% μ γ κ p α % β % μ γ / α y%(β % μ γ )q α % β % μ γ & μ γ s α % β % μ γ in round a trader observes p which is a function of the same three variables and of p . given p and the fact that , he infers from that s - n( , γ ) p 'κ ( λ y%μ q&s % ξ p ) . κ μ ( p & κ λ y & κ ξ p ) ' q& s μ - n ( q , μ γ ) he now updates ( a)-( b). since supply shocks are i.i.d. the updated posterior is standard .e i(q | h i )' [ (α&μ γ λ )y%βx i % μ γ κ p α % β % μ γ ](α%β%μ γ ) % κ μ (p &κ λ y&κ ξ p )(μ γ ) α % β % μ γ % μ γ simplification leads to ( b) e i( q | h i ) ' [ α & μ γ λ & μ γ λ ] y % βx i %[ μ γ κ p % μ γ κ p & μ γ ξ p ] α % β % μ γ % μ γ ( c) . var( q | h i ) ' α%β%μ γ %μ γ to compute ( c) we average ( b) to conclude that ( a) ē ( q ) ' [ α & μ γ λ & μ γ λ ] y % βq%[ μ γ κ p % μ γ κ p & μ γ ξ p ] α % β % μ γ % μ γ ( b) .ē ( p ) ' κ ( λ y % μ ē ( q ) % ξ p ) when ( a)-( b) are inserted into ( c) we end up with two equations in the two unknown prices which can now be computed. the final step is to match coefficients of the price functions ( a)-( b) in order to identify ( , ξ ). for details of these computations see allen, morris and shinκ , λ , μ , κ , λ , μ for discussion of the “long lived” traders see he and wang ( ) and appendix a of allen, morris and shin ( ). for a simple exposition of the hedging demand in a two period economy see brown and jennings ( ). ( ) , appendix a. it is useful to write the forecasts ( b) and ( a) in terms of unknown variables: ( b’) e i( q | h i ) ' αy % βx i % ( μ γ % μ γ )q α % β % μ γ % μ γ & μ γ s % μ γ s α % β % μ γ % μ γ ( a’) .ē ( q ) ' α y % (β%μ γ %μ γ )q α % β % μ γ % μ γ & μ γ s % μ γ s α % β % μ γ % μ γ what is the length of memory in prices? the model is static but multiple trading rounds provide opportunities to deduce more information from prices about q, revealed after n rounds. as trading continues, the memory of all past prices is preserved since prices depend upon all unobserved supply shocks. in such a case the price system can never be a finite memory markovian process. the model has, indeed, been extended to multi period trading where q is revealed n periods later (see brown and jennings ( ), grundy and mcnichols ( ), he and wang ( ) and allen, morris and shin ( )). in these models the complexity of inference depends upon the presence of a hedging demand of long lived traders . however, for both long and short lived traders the number of trading rounds is an arbitrary modeling construct. it would thus be instructive to examine the limit behavior of the model. in a third round of trading by the short lived traders the price map becomes .p 'κ ( λ y%μ q&s % ξ p % ξ p ) hence, the independent supply shock leads to an updating rule which is again standard .e i(q | h i )' e i(q | h i ) (α%β%μ γ %μ γ ) % κ μ ( p &κ λ y&κ ξ p &κ ξ p )(μ γ ) α % β % μ γ % μ γ % μ γ simplification and averaging over the population leads to the market forecast ē ( q ) ' [ α & μ γ λ & μ γ λ & μ γ λ ] y % βq α % β % μ γ % μ γ % .% μ γ κ p % μ γ κ p % μ γ κ p &μ γ ξ p &μ γ ξ p &μ γ ξ p α % β % μ γ % μ γ as in ( b’) individual and market forecasts can be expressed in terms of the unobserved variables. they can easily be extended to n rounds of trade and take the general form ( ) e i(q | h i n ) ' αy % βx i%j n j' μ j γj q α % β % j n j' μ j γj & j n j' μj γj sj α % β % j n j' μ j γj a standard argument shows the converge. for simplicity assume the precision of sj is constantμj hence = γ. the independence property of the noise with ( ) and the law of large numbers imply thatγj the first term converges to q and the second converge with probability to . hence, in the limit, with probability all forecasts converge to the true q and the effect of the public signal y disappears. hence, repeated trade leads to a full revelation of the true value q. moreover, in the limit p = q and traders do not forecast prices at all. if the unit of time is, say, a month the rounds of trade are not really limited. hence the result contradicts allen, morris and shin’s ( ) claim that the effect of the public signal y on the price lingers on forever. with sufficient trading the effect of y disappears. to conclude, the study of markets with private information has advanced our understanding of risk sharing and insurance markets. here we examine its limits. with different information agents clearly make different forecasts. but private information is a very sharp sword. hence, when diverse forecasting is an important component of a theory, the temptation is to assume private information to model diversity. a large literature has done just that. it is so common that for some, thinking of agents with different opinions is synonymous to thinking of them as having different private information. for forecasting market aggregates this equivalence is wrong and the assumption of private information has no merit. we identify three areas of forecasting where the model of diverse beliefs is the correct one: (i) market prices such as interest rates, indices of stock prices, foreign exchange rates ; (ii) macroeconomic variables such as rates of gnp growth, inflation, unemployment, monetary policy actions; (iii) exogenous shocks like productivity shocks, aggregate factor supplies etc. unfortunately there are many contributions which use models with asymmetric private information to solve problems in which traders forecast variables in the above three categories. examples include phelps ( ) and lucas ( ) but recent examples include romer and romer ( ), hellwig ( ), woodford ( ), amato and shin ( ) bacchetta and van wincoop ( a) and others. to illustrate, kurz ( b) explains the volatility of foreign exchange rates and the forward discount bias in foreign exchange markets by demonstrating that these are consequences of diverse beliefs of traders about future exchange rates. in rejecting the ree framework he assumes agents hold diverse rational beliefs which are restricted as explained in section . below. in such a market the center of uncertainty is the uncertainty of traders about future beliefs of other traders. bacchetta and van wincoop ( a) adopt the same idea by using a noisy ree but assume that at each date traders have random private information about future aggregate money supply. hence traders are uncertain about future private information of other traders. our argument here is that in the context of exchange rates determination such an assumption does not have empirical validity and hence leads to an implausible explanation of the forward discount bias. our view is then that the economic explanation provided by these papers is flawed and questionable . to compare with theories under diverse beliefs, we interpret the asset value q in the noisy ree literature to be an aggregate value such as the s&p , an interest rate or an exchange rate. before formulating our hb model, we observe that the simple model discussed above leads to several natural objections against models where traders use private information to forecast variables in the three categories listed above. these natural objections do not depend upon the formulation of any specific heterogenous belief model. for this reason we outline these first. . when should the assumption of asymmetric information be avoided? in casting significant doubt on the validity of the pi assumption we recall that the typical problem studied with pi include market volatility, aggregate risk premia, foreign exchange dynamics, business cycles, the effects of monetary policy, etc. apart from the fact that the assumption of private information is not plausible, we also argue that the explanations offered for these phenomena, driven by private information, are unconvincing. thus, pi offers a distorted “solution” for such problems. (i) what is the data that constitutes “private” information? if forecasters of gnp growth or future interest rates use pi, one must be able to specify the data to which such forecasters have an exclusive access. forecasters of macroeconomic variables, including the federal reserve itself, state their data sources and universally claim they use only published data. more important, without an explicit identification of the private information used by a forecaster, a model with pi does not make sense. indeed, all empirical implications the model has are deduced from restrictions imposed by that information. as illustrated in section , a model with pi specifies an unknown parameter q about which agents receive private signals with for this to have meaning one must knowx i t i ' , , . . . what the are or what they could conceivably be. when agents forecast aggregate variables in thex i t three categories above, no such imaginary data exist. (ii) asymmetric information imply a secretive economy. forecasters take pride in their models and are eager to make their forecasts public. as a result, there are vast data files on market forecasts of most of the variables mentioned. these include data of the blue chip economic indicators (blu), blue chip financial forecasts (bluf), the survey of professional forecasters (spf), forecasts by individual firms engaged in forecasting and even detailed forecast data of the staff of the federal reserve system. such data are being used more and more in economic research as (e.g. romer and romer ( ), swanson ( ), kurz ( ), kurz and motolese ( ) ). in addition to making public their forecast data, forecasters stress their opinions are different from others. in discussing public information they explain their own interpretation of such information often framed as “their thesis”, the weight they place on it and their disagreement with others’ use of that same information. trade journals are used to debate forecasting techniques and in public competitions prizes are awarded to the best forecaster in specified categories. since pi gives clear advantage to those who have it other forecasters would not compete since there is nothing to compete about. in short, forecasters view their work as model formulation and interpretation of information, not a reflection of secret information to which they are privy. such behavior is not compatible with an equilibrium with pi. in contrast, an equilibrium with pi is secretive. individuals are careful not to divulge their pi since it would deprive them of the advantage they have. in such an equilibrium all private forecast data of any state variable (e.g. productivity) are treated as sources of new information. agents use forecast data of other forecasters to update their posterior beliefs about that state variable. had such pi been deduced from forecasts, the mean market forecast would change. since in reality all forecasters happily reveal their forecasts, the economy must converge to an equilibrium with uniform information. the eagerness of agents to reveal their forecasts is thus not compatible with pi being the cause of the persistent divergence of opinions and forecasts. (iii) for the problems considered, asymmetric information is not sufficient. implicit in (ii) is the fact that in ree with pi, there is basic tension between information asymmetry and revelation\learning. if prices reveal pi the model has noise to prevent such revelation. noise must be unobserved and the cause for the noise is often unspecified. when specified, it takes strange forms such as an unobserved random supply of the asset. but then, the implications of the theory do not depend only upon the private information available but, more important, on the investigator’s noise. the problem does not end there. as we have seen, repeated trading overcomes the effect of noise and leads to full revelation. since the number of rounds of trade is a model construct, the empirical implications of the model are affected by an artificial component constructed in the model. finally, there are other channels that affect the revelation of pi. for example, private forecast data is available and is extensively used (otherwise the data would not be collected). given the assumption of pi, much information could then be deduced from private forecasts. hence, any implications of theories based on pi cannot depend only upon prices; they must also depend upon other channels for inference. without credible and observable ways to measure these channels of revelation the theory lacks empirical implications. also, there are other formulations of the private information model in real time (e.g. judd and bernardo ( ), ( ), bacchetta and van wincoop ( a), wang ( )) but we do not review them here. (iv) if private signals are unobserved, how could common knowledge of the structure be attained? to permit a deduction of pi from public data the structure of the private signals must be common knowledge. for example, they may take the form where are pure noise, independentx i ' q % εi εi across traders. but then one asks the simpler question: if these signals are not publically observed, how does the common knowledge come about? how does agent i know that his own signal takes the form and that is an unbiased estimate of θ? how does trader i knows that the signal of k x i ' q % εi x i takes the form ? are these not merely devices used by the investigator to enable a closedx k ' q % εk form solution of the bayesian inference problem, rather than an empirically verifiable hypothesis? (v) why are private signals more informative than audited public signals? one peculiar assumption that drives the results of morris and shin ( ), allen, morris and shin ( ), bacchetta and van wincoop ( a) and others, is explained in the model of section . it says that traders get a public signal y which is the mean value of the unknown q. knowing the prior mean of q is clearly inferior to knowing the true q. it is then assumed there is a continuum of agents on [ , ] with x i ' q%εi and with i.i.d. hence, if you knew all private signals you would use the law of large numbers toεi aggregate them and learn the true q. in an ree it is assumed there is some agent who aggregates the information and hence equilibrium price becomes a function of the true q, which nobody knows. but this procedure raises two questions. (a) why do private signals contain more precise information than the professionally audited statements? does it make sense to postulate that audited statements are less reliable than the sum of all the fragmentary signals that individuals obtain? (b) who is doing the aggregation? how does he know the i.i.d. structure needed to arrive at an aggregation? what are the incentives of this aggregating agent? if he is a neutral agent with a duty not to exploit the public, why does he not simply announce q? or else, he must be part of the model. (vi) with asymmetric information you can prove anything. a typical model with pi is based on the fact that crucial components of the theory can never be observable. we shall never observe the private signals agents had about gnp growth or about future value of the s&p . this lack of observability is contrasted with the case of insurance markets where driving records or health records can confirm the assumption that agents have pi which, ex ante, is not available to firms in the insurance market. but if there is no way to ever obtain data on the crucial component of the theory, the theory cannot be falsified: for any hypothesis about market behavior one can find a pattern of pi that would induce that behavior as an equilibrium behavior. the theory has no empirical restrictions and without restrictions it has no scientific content. . modeling asset pricing under hb with public information only we now turn to the alternative paradigm of hb instead of private information. what are the differences between these two theories and do these differences matter? . adaptation of the earlier model to adapt the model of section with pi to a market with hb and only public information, we clearly reject the common knowledge assumptions made. but then what is common knowledge among traders with diverse beliefs? our unequivocal answer is past data on observable variables. traders know they all observe the same data. they have diverse beliefs about the future because they have diverse interpretations of past data. hence, a mechanical adaptation of the two- period economy in section is not suitable for an economy with hb. a meaningful model with hb must be anchored in real time with past data available at each date. to permit a comparison we thus adapt the earlier model by preserving its key assumptions. apart from private information, the key assumptions are: (i) traders live finite life and derive utility from the terminal value of their net wealth; (ii) at date agents cannot trade futures contracts for delivery of the stock at date ; (iii) at date traders must form beliefs about the price at date and the true liquidation value . this changed notation will be clarified later.q̂ our adaptation is then based on two principles. first, we maintain the above assumptions. second, we require that our model generates exactly the same demand functions as the pi model in ( a) -( b) so the comparison is reduced to differences between the implied probabilities used. since under hb traders need price history to form beliefs, we assume trading is carried out by generations of traders, each of whom trades for two periods. in our setting a trader who starts trading at date t trades again at date t + and retires at the end of t+ , after is revealed and the value of his holdings isq̂t% set. at retirement he exchanges his stock for consumption goods. hence, at each t there are two types of overlapping traders: one group whose trading career is launched at t- and who retire at the end of trading at t, and a second group launched at date t, and who retires at t+ . our economy consists of a continuum of traders of each type. as was the case in the pi model, we do not explicitly model the entire economy with consumption, investment, and production. the real economy is the background and the model is used to study the behavior of risk taking investors who use financial markets to trade risk. as in the pi model we assume their utility is defined only over gains from trading risk hence comparison of asset returns is a comparison of risk premia in an economy under pi vs risk premia under hb. with a real economy in the background we follow the pi literature and assume a constant riskless interest rate and without loss of generality let it be zero. the traded stock reflects an aggregate collection of assets kept in the background about which true audited information is revealed at the end of each date. these valuations are then used to compensate the retiring traders for risk taking. is the value revealed at date t and the long history of for k = , , ..., t is known atq̂t q̂k date t hence traders use past data to compute the finite dimensional distributions of the observations. clearly, all compute the same empirical moments. using standard extension of measures they all deduce from the data a unique probability measure on infinite sequences denoted by m. it can be shown that m is stationary (see kurz ( )) and we call it “the stationary measure.” this is the empirical knowledge shared by all. to conform to the earlier model assume the data reveals the areq̂t it would probably be more realistic to assume that the values qt grow and the growth rate of the values has a mean μ rather than the values themselves. this added realism is useful when we motivate the model later but is not essential for the analytic development. without altering any of our results we could initiate trading with an endowment of a real commodity as in ordinary overlapping generation models. this is a consequence of the fact that under the utility function in ( ) there are no income effects. had we included such endowment, the definition of wealth would simply include it. model consistency clearly requires the sum of shares surrendered by date t- retiring traders to equal the sum of shares allotted to new traders at date t. this assumption is inconsequential since young traders take the share allotment as exogenous and with free borrowing and without wealth effects the rule for initial shares allotment has no effect on optimal portfolios. an alternative procedure would be to treat the initial endowment as a loan in the form of shares borrowed. this would then lead to the requirement that the trader must return the loan and the amount would be subtracted froms it (qt% %μ) terminal wealth. conditionally normally distributed with mean μ and precision . now define . a theory ofα qt ' q̂t & μ belief diversity flows from the fact that traders do not know the true probability distribution of the ‘s. that is, the stochastic process { } has an unknown probability Π. traders knowqt qt , t ' , , . . . only the stationary probability m deduced from data. the distinction between m and Π is central to our development and is explored later when we describe the belief structure. here we note traders’ beliefs at date t are conditioned on common information which consists of past values of for k =ht qk , , ..., t and prices. as in the pi model, trader i is launched at t (he is “date t” trader) with an endowment of shares but the total supply is a constant, not random. our notation is:s i t - the endowment of shares with which trader i is launched at date t;s i t - date t demand of trader i who is launched at date t;d i t - date t+ demand of trader i who is launched at date t;d i t% s - total constant supply of shares. traders borrow or hold cash at the riskless rate hence they trade between the aggregate asset and cash. under the utility function in ( ) the assumption of an endowment of shares is a convenients i t assumption with absolutely no effect on the results. with endowment and borrowing a trader purchases his initial stock position at the cost of . at t+ he traders again into the positiond i t d i t pt . at the end of date t+ the audited valuation of the asset is revealed. given the traderd i t% qt% qt% exchanges his stock position for real commodities and retires. the shares of retiring traders ared i t% then used for the initial endowment to the next generation of traders . a trader has a preference over risky capital gains. his net terminal wealth is and hisw i t% 's i t pt%d i t ( pt% &pt )%d i t% ( qt% %μ &pt% ) date t+ utility is ( ) .u( w i t% ) ' & e &( w i t% τ ) , w i t% 's i t pt%d i t ( pt% &pt )%d i t% ( qt% %μ &pt% ) ( ) shows that on the demand trader i makes gains or losses of while gains on d i t d i t ( pt% &pt ) d i t% are . the realized has informational value to a date t trader since it is a signald i t% ( qt% %μ &pt% ) qt for . apart from this, it has no impact on his wealth since is payment to retiring portfolios at t.qt% qt in short, with a real economy in the background agents in our model redistribute risk in accord with their beliefs or information. this is exactly the spirit of the pi model. trader i who is launched at date t selects an optimal trading strategy which sequentially solves ( a) j i t% ( d i t ) ' max d i t% e i &exp[& τ ( s i t pt % d i t ( pt% &pt )%d i t% ( qt% %μ &pt% )] | ht% ( b) j i t 'max d i t e i max d i t% e i &exp [& τ (s i t pt %d i t ( pt% &pt )%d i t% (qt% %μ &pt% )] | ht% | ht . ( a) solves for , given date demand function, while ( b) solves for i’s demand in date . thed i t reasoning presented earlier for computing the demand functions applies here as well. they are ( a) .d i t% ( pt% ) ' τ var i (q t% | h t% ) [ e i(q t% | h t% ) % μ & p t% ] ( b) .d i t ( pt ) ' τ g [ e i(pt% | ht ) & pt ] % ( g & g ) g [e i ( d i t% | ht )] is our adaptation of the model reasonable? since our trader lives for two periods (he is “long lived”) we incorporate the hedging demand. but, as required, our demand functions are identically the same as in the model with pi: ( a)-( b) and ( a)-( b) are exactly the same functions. the crucial difference between the private information and the heterogenous belief models are the expectations of traders in ( a)-( b) and ( a)-( b) and the information they are assumed to have. we also observe that, although somewhat artificial, the assumption of a share endowment to new traders removes alls i t intergenerational effects of a trader’s decision. indeed, the equality of the demand functions together with the device of the share endowment attains model consistency and ensures that the infinite time horizon in our model has no independent effect. that is, the facts that the first model is of a finite horizon economy and the second is imbedded in an infinite horizon economy do not lead, on their own, to different implications of the two models. the infinite repetition introduces the driving force of diverse beliefs which is the fact that Π, the true probability of the process { }, is unknown. the model is given an economicqt , t ' , , . . . the model could be modified to the more famialr form where { } are the usual risky dividends. inqt , t ' , , . . . that case date t trader buy assets at date t and at date t+ . he receives dividends and for investmentsd i t d i t% qt% %μ qt% %μ made at dates t and t+ respectively. dividend payments are paid, as usual, at the start of a period and are known at the time of trading. as a result, date t trader retires at the start of date t + and when he liquidates his position by selling it into the market for the value of . uncertainty about is now thew it% 'd i t (pt% %qt% %μ &pt )%d i t% ( pt% %qt% %μ &pt% ) ( qt% , qt% ) uncertainty about profits. computing the implied demand functions we find that they are slightly different from ( a)-( b). we elected to stay with the problem ( a)-( b) and demand functions ( a)-( b), which offer an entirely reasonable analytical platform with which to carry out the comparison we seek. interpretation via a collection of real assets, kept in the background. these experience changes in innovation and organization so the time variability of the mean values of { } is driven byqt , t ' , , . . . the forces of change. the terminal wealth of trader i, who is initiated at date t, depends upon . ifqt% he does not trade, his terminal net wealth is . but then, what does thew i t% ' s i t ( qt% % μ ) liquidation value reflect? it is clear this value is a compensation for taking risk associated with net profits of the background assets and results from the fact that date t uncertainty is resolved only after date t trading. risk taking of this sort takes place in diverse sectors such as agriculture, mining, oil extraction, real estate and others. in these arrangement an investor buys an equity position which is tradable. the capital in the venture typically consists of the cumulative net output of the venture. in agriculture it may be the grain produced at the risky harvest, in oil extraction it may be oil discoveries, in mining it may be minerals discovered, in venture capital it is the realized valuation at the public offering. thus, ownership shares allow risk sharing of the prospects involved and liquidation by the retiring members is permitted when the outcome of date t venture is known (i.e. size of crops, amount of oil found, outcome of a venture capital project, etc.). more generally, the market price reflects the valuation of the risky prospect while the liquidation value is the known benefit of the venture when it matures. when trading is resumed at date t+ the venture continues into its next phase with new activity, new members and a new true value that will become known after trading. this, of course, is the assumption made in the pi model and since we want the demand functions of the two models to be identically the same, we must adopt this same concept as well. in the next section we model the structure of traders’ beliefs, which is central to this paper. we have stressed that disagreements arise from diverse interpretation of the same empirical record. thus, to conclude this section we make the simple assumption that the empirical frequencies of recorded past values is known by all to imply a first order markov process described by a stationary transition ( ) .qt ' λq qt& % ρ q t , ρ q t - n( , σ q ) since the implied stationary probability is denoted by m, we write .e m[qt | qt& ] ' λq qt& is the stationary model ( ) with probability m the true data generating mechanism and hence is it the case that m = Π? if the environment was stationary and if all traders knew it was stationary, the ergodic theorem says that all would know the true data generating process. indeed, in that case it would be common knowledge that ( ) is the truth. in reality such conditions do not hold. the economy undergoes rapid changes with structural breaks associated with periods of high or low productivity. the process { } is then non-stationary under the true probability Π whichqt , t ' , , . . . is not known to anyone. a stationary markov empirical record is simply an average over different regimes. in particular, the first order markov property is a result of diverse dynamic patterns, averaged out statistically over time. the simple analogy we can give for the empirical frequencies of past values is like running a single regression over a long data set with many unobserved regimes. such a procedure estimates the average over different structures. but, for long data sets, this is all that they could ever agree on. the fact is that traders do not believe the empirical distribution of the past is adequate to forecast the future. all surveys of forecasters show that subjective judgment contributes more than % to the final forecast (e.g. batchelor and dua ( )). in this environment each trader forms his own beliefs about qt and other state variables to be explored in the next section. with such complexity how do we describe an equilibrium? for such a description do we really need to give a full, detailed, development of all the diverse theories of the traders? . heterogeneity of belief: the question is how! diverse beliefs is the result of the fact that agents do not know the exact structure of a complex economy. since one cannot be declared irrational if one cannot hold rational expectations, the concept of rationality must be modified. the theory of rational beliefs (in short, rb due to kurz ( ), ( a)) defines a trader to be rational if his model cannot be falsified by the data and if simulated, it reproduces the empirical distribution. under this theory rational traders may hold diverse forecasting models based on different interpretations of the data. more generally, without a compelling known “true” model, any meaningful concept of rationality of belief will embrace a wide collection of models. such a conclusion raises a clear methodological question. in formulating an asset pricing theory should we provide a detailed description and motivate the subjective models of each trader in the model? with diversity of traders such a task is formidable. but if the objective is an understanding of the dynamics of asset prices, is such a detailed description necessary? an examination of the subject reveals that, although an intriguing question, such a detailed task is not needed. instead, to describe an equilibrium all that we need is to specify how the beliefs of the traders affect their subjectively perceived transition functions of all the state variables. once these are specified, the euler equations are fully specified and market clearing leads to equilibrium pricing. to carry out such a program we follow the structure developed in kurz, jin and motolese ( a), ( b). we now outline this development for traders in our simple asset price model. . market belief as a state variable: diverse opinions vs. asymmetric information in markets without private information agents are willing to reveal their forecasts. hence, in formulating our theory we now assume that market forecast data are public. the crucial difference between markets with and without private information is that when individual forecasts of a state variable are revealed in a market without private information, others do not see such forecasts as a source of new data and do not update their own beliefs about a parameter used to forecast that state variable. in such a market, a forecaster uses knowledge about the forecasts of others to alter his forecasts of endogenous variables since these depend upon the market belief. in short, the difference between an equilibrium with pi and an equilibrium without pi but with hb is that in the latter agents do not learn from others and do not update their beliefs about state variables based on the opinions of others. but then, how do we describe the individual and market beliefs? the key analytical step we have taken (see kurz ( ), kurz ( a), kurz and motolese ( ), kurz, jin and motolese ( a),( b)) is to treat individual beliefs as personal state variables, generated within the economy. that is, an individual belief about an economy’s state variable are described with a personal state of belief which uniquely pins down the conditional probability or transition function of next period’s economy’s state variable. hence, personal states of belief are analogous to other state variables in the decision problem of the agent, although iy can also be interpreted as defining the more familiar concept of a “type” of the trader. at date t the trader is not certain of his future belief type but his behavior (e.g. bayesian updating) or procedural model and interpretation of current information determines the dynamics of the personal state of belief. the distribution of individual states of belief then becomes a central economy-wide dynamical force where the cross sectional average state of belief is simply the average of individual beliefs. as we indicated, the crucial fact is that the distribution of beliefs in the market is observable. in equilibrium, endogenous variables (e.g. prices) depend upon the economy’s state variables, but in a large economy a trader’s “anonymity” implies a personal state of belief has a negligible effect on prices. it turns out that with the utility function we use equilibrium endogenous variables depend only upon the distribution of market beliefs. thus, as in any equilibrium, prices and other endogenous variables are functions of the economy’s state variables and here these state variables include the distribution of personal beliefs. in our equilibrium the moments of the cross sectional distributions of belief are important economy state variables and their stochastic transition laws play a central role. finally, since endogenous variables are functions of the market beliefs, it follows that future endogenous variables are forecasted by forecasting the market distribution of beliefs using the known equilibrium map. in short, to forecast future endogenous variables a trader must forecast the beliefs of others. we thus introduce trader i’s state of belief . it describes his perception by pinning down hisg i t transition functions. adding to “anonymity” we assume trader i knows his own and the marketg i t distribution of across k. as to past, he observes past distributions of the for all τ < t hence heg k t g k τ knows past values of the moments of the distributions of the . we specify the dynamics of by g k τ g i t ( ) g i t ' λz g i t& % ρ ig t , ρ ig t - n( , σ g ) where are correlated across i reflecting correlation of beliefs across individuals. the concept ofρ ig t an individual state of belief, with dynamics ( ), is central to our development. here we state ( ) as a positive description of type heterogeneity but in section . we prove ( ) as a consequence of a bayesian updating procedure. we postpone this demonstration in order to explain first the asset pricing theory implied by our model of hb. we note that in general is used to express a trader’sg i t assessment of the difference between date t distribution of an observable state variable and the empirical distribution m. in the model of this paper the perception of trader i regarding at date tqt (denoted by ) is described by using the belief state as followsq i t g i t ( a) .q i t ' λq qt& % λ g q g i t % ρ iq t , ρ iq t - n( , σ̂ q ) the assumption that is the same for all traders is made for simplicity. it follows that the state ofσ̂ q belief measures the deviation of his forecast from the empirical stationary forecastg i t ( b) .e i [ q i t | ht , g i t ] & e m [ qt | ht ]' λ g q g i t indeed, ( b) shows how to measure in practice. for any state variable xt, data on i’s forecasts ofg i t xt (in ( b) it is qt ) are measured by . one then uses standard econometric techniquese i [ x i t | ht , g i t ] keep in mind the unnatural timing in the model. at date t trader i has a state of belief about variables he doesg it not know. these are: (i) qt to be announced at the end of date t, and (ii) zt+ to be revealed at the start of t+ . this peculiar timing is a consequence of the timing in the private information model presented in the introduction according to which qt is revealed at the end of date t. also, for simplicity we assume ( a)-( b) is the same across traders: diversity is in the .g it to construct the stationary forecast with which one empirically constructs the differencee m [ xt | ht ] in ( b). this construction and the data it makes available are at the core of the papers by fan ( ) and kurz and motolese ( ). a trader type who believes the empirical distribution is the truth, is described by , hence he believes that . since belief heterogeneity is theg i t ' qt - n (λq qt& , σ q ) result of dynamic non-stationarity of the economy, it should be clear that around the subjective assessments of the were related to the development of electricity and the combustion engine, whileg i t around the belief measured the impact of computers and information technology. hence,g i t success or failures of past do not really tell you anything what present day should be. thisg i τ g i t issue is further explored in section . and for additional details see kurz ( a). denote by the first moment of the cross sectional distribution of the and we refer to it aszt g i t “the average state of belief.” it is observable. due to correlation across traders, the law of large numbers is not operative and the average of over i does not vanish. we write it in the form ρ ig t ( ) .zt% ' λz zt % ρ z t% the true distribution of is unknown. correlation across agents exhibits non stationarity and thisρ z t% property is inherited by the { zt , t = , , ...} process. since zt are observable, market participants actually have data on the joint process { }. traders are thus assumed to know( qt , zt% ) , t ' , , . . . the joint empirical distribution of these variables. for simplicity we assume that this distribution is described by the system of equations ( a) qt ' λq qt& % ρ q t ρ q t ρ z t% - n , σ q, , , σ z ' Σ , i.i.d. ( b) zt% ' λz zt % ρ z t% now, a trader who does not believe that ( a)-( b) is the truth for t, formulates his own model\belief. we have seen in ( a) how trader i’s belief state pins down his forecast of . we now broadeng i t q i t this idea to the trader’s perception model of the two state variables . keeping in mind that( q i t , z i t% ) before observing qt trader i knows , his belief takes the general symmetric form qt& and zt ( a) q i t ' λq qt& % λ g q g i t % ρ iq t ρ iq t% ρ iz t% - n , σ̂ q, σ̂zq, σ̂zq, σ̂ z ' Σi , ( b) z i t% ' λz zt % λ g zg i t % ρ iz t% although the belief state was initially defined to be about the unknown value , ( a)-( b)g i t qt show that we use it also to pin down the transition of . we could have, instead, introduced a newz i t% variable to express belief about future z. we avoid this procedure for simplicity and in order tog iz t avoid an artificial problem of infinite regress. hence, expresses how the agent considers theg i t present conditions to be different from the empirical distribution: ( c) e i t q t zt% &e m t q t zt% ' λ g q g i t λ g z g i t the average market expectation operator is loosely defined by . from ( c) it isēt (c ) ' me i t (c) di ( d) . ēt q t zt% & e m t q t zt% ' λ g q zt λ g z zt the perception models ( a)-( b) explains why the average individual market belief is not a proper probability. to see this let be a product space where take their values and let gix ' q × z (qt& , zt) be the space of the . since i conditions on his own , his unconditional probability is a measureg i t g i t on the space where öi is i’s sigma field. hence, the average market conditional( ( q × z × g i) ,öi ) belief is an average of conditional probabilities, each conditioning on a different state variable. hence, one cannot write down a probability space for the market belief and we have the following result: theorem : the average individual belief violates iterated expectations: .ēt (qt% ) … ēt ēt% (qt% ) proof: from ( a)-( b) we know that .e i t ( qt% ) ' λq e i t ( qt ) % λ g q e i t (g i t% ) ' λq [λq qt& %λ g q g i t ] % λ g q λzg i t it follows that ( a) .ēt ( qt% ) ' λ q qt& %λ g q ( λq % λz ) zt on the other hand ( a) implies ēt% ( qt% ) ' λq qt % λ g q zt% hence e i t ēt% ( qt% ) ' λq [λq qt& % λ g q g i t ] % λ g q [λz zt % λ g zg i t ] and aggregating now to conclude that ( b) .ēt ēt% (qt% ) ' λ q qt& % λ g q (λq % λz % λ g z ) zt comparison of ( a) and ( b) shows that . �ēt ( qt% ) … ētēt% ( qt% ) belief and information: understanding what is . from the perspective of a trader, is a statezt zt variable like any other. news about are used to forecast prices and assess the time variability ofzt market risk premia in the same way macroeconomic data such as gnp growth or non farm payroll are used to assess the risk of a recession. market belief may be wrong as it may forecast recessions that never occur. market risk premia may fall just because traders are more optimistic about the future, not necessarily because there is any specific data which convinces everybody the future is bright. but then, how do traders update their beliefs when they observe ? in sharp contrast with the pi theory,zt traders do not revise their own beliefs about the state variable ; ( ) specifically does not dependqt upon . traders do consider as new information about since they know all used all availablezt zt qt information. without being a “signal” about unobserved private information, is not used to updatezt beliefs about exogenous variables. the importance of is it’s great value in forecasting futurezt endogenous variables. date t endogenous variables depend upon and future endogenous variableszt depend upon future market belief. since market belief exhibits persistence, traders know that today’s market belief is useful for forecasting future endogenous variables. how is this equilibrated? this is what we show now. . combining the elements: the implied asset pricing theory under diverse beliefs we now derive equilibrium prices under hb. denote the conditional variance of qt (common to all traders) by . by ( a)-( b) we write the date t demand functions of the two type of traders as σ q ( a) .d i t ( pt) ' τ σ q [ e i(q t %μ | h t ) & p t ] ( b) .d i t ( pt ) ' τ g [ e i(pt% | ht ) & pt ] % ( g & g ) g [e i ( d i t% | ht )] for an equilibrium to exist we need some stability conditions. to specify these we introduce the notation . now we add:δ ' & g / ( g %σ q) stability conditions: we require that . < λq < , < λz % λ g z < , < |δ | < the first requires {qt , t = , , ...} to be stable and have an empirical distribution. the second is a stability of belief condition. it requires i to believe is stable. to see why take expectations of( qt& , zt ) ( b), average over the population and recall zt are market averages of the . this implies that g i t .ēt [ zt% ] ' (λz % λ g z ) zt theorem : for the model with hb and under the specified stability conditions, there is a unique equilibrium price function which takes the form .pt ' a ( qt& % μ ) % b zt & c s proof: aggregating ( a) over all retiring traders and ( b) over all new traders at date t leads to ( a) .d̄ t ( p t ) ' τ σ q [ ē t ( q t %μ ) & p t ] ( b) .d̄ t ( pt ) ' τ g [ ēt( pt% % qt % μ ) & pt ] % ( g & g ) g τ σ q [ ēt( qt% %μ ) & ētpt% ] ] since we add ( a)-( b) to conclude thatd̄ t ( pt) % d̄ t ( pt) ' s .s ' τ σ q [ ēt( qt % μ ) & pt ] % τ g [ ēt( pt% % qt % μ ) & pt ] % ( g & g ) g τ σ q [ ēt ( qt% %μ ) & ēt [pt% ] ] hence .s ' ( τ σ q % τ g )[ēt( qt %μ )&pt ]%( τ g )[ & ( g &g ) σ q ] ēt ( pt% )% ( g &g ) g τ σ q [ ēt( qt% %μ )]] now use the perception models ( a)-( b) about the state variables, average them over the population and use the definition of zt to deduce the following relationships which are the key implications of treating individual and market beliefs as state variables ( a) ēt(qt ) ' λq qt& % λ g q zt ( b) ēt ( qt% ) ' (λq) qt& % [λq λ g q % λ g q λz ] zt ( c) .ēt(zt% ) ' (λz % λ g z ) zt now solve for date t price to deduce ( ) .pt ' ēt ( qt % μ ) % ( g &g ) g % σ q ēt ( qt% %μ ) % σ q %g &g g % σ q ēt ( pt% ) & σ q g g % σ q [ s τ ] observe that ( a)-( c) together with ( ) imply that equilibrium price is the solution of the following difference equation ( ) pt ' a ( qt& % μ ) % b zt % δ ēt [ pt% ] & c s , δ ' σ q%g &g g %σ q with , , .a ' λq % ( g &g ) g % σ q λ q b ' λ g q % ( g &g ) g % σ q [λqλ g q % λ g q ( λz % λ g z ) ] c ' ( τ ) σ q g g % σ q ( ) is a linear difference equation in the two state variables . hence, a standard argument( qt& , zt ) (see blanchard and kahn( ), proposition, page ) shows that the solution is ( a) pt ' c ( qt& % μ ) % c zt & c s with matching coefficients of ( b) c ' [ & δλq ] ( g &g ) g % σ q λ q ( c) c ' &δ( λ z %λ g z ) λ q g % ( g &g ) g % σ q (λq λ g q % λ g q (λz % λ g z ) ) % ( δλ g q & δλq ) ( g &g ) g % σ q λ q ( d) .c ' ( & δ ) σ q g τ ( g % σ q )the stability conditions ensure that ( a) - ( d) is the unique solution as asserted. � finally, recall that the demand functions ( a)-( b) were computed under the conjecture that prices are conditionally normally distributed. theorem provides the final confirmation of this conjectures. . deducing the markov belief process from bayesian inferenceg it ' λz g i t& % ρ ig t our key analytical tool is the state of belief and we now justify the dynamics ( ). keeping in mind that we study asset pricing in a changing environment, our first justification is simplicity and analytic tractability as seen in the developments in sections . - . . in a changing environment there is no universal procedures to learn an unknown sequence of parameters. it is thus less important to explain why agents disagree and more important to be able to describe their diversity so that an equilibrium analysis is tractable. the description ( ) of a state of belief in the form g i t% ' λz g i t % ρ ig t% where leads to a simple and useful description of equilibrium asset pricing withρ ig t% - n( , σ g ) diverse beliefs. it also shows that in contrast with pi theories, it does not entail extraction of information from market prices. instead, it requires different agents to have different state spaces for description of their uncertainty. it also requires the endogenous expansion of the economy’s state space for a description of equilibrium pricing. we now explore the conditions under which the markov dynamics ( ) is proved as a consequence of elementary principles of bayesian inference. before proceeding we formulate the problem in a setting which is more general than the one where an intrinsic value qt is revealed. instead, we assume the observable variable is the dividend dt paid by an asset before trading takes place. this will result in a more natural timing than in the case of the model developed earlier. the economy unfolds over an infinite horizon and agents have a long history of data, allowing statistical analysis which leads all to compute the same empirical moments and the same finite dimensional distributions of the observations. hence they all deduce from the data a unique empirical probability on infinite sequences denoted by . it can be shown that ism̂ m̂ stationary. we assume the data reveals that under the constitutes a markov processm̂ dt , t' , ,... where is conditionally normally distributed with means and variance . now wedt% μ %λd (dt&μ) σ d define , hence { } is zero mean with unknown true probability Π and andt ' dt & μ dt , t ' , ,... empirical probability m. we shall assume that under the true Π the { } is a non-stationarydt , t ' , ,... process but under the assumptions made above the empirical probability of { } is deduceddt , t ' , ,... from the data and is characterized by a first order markov process with a stationary transition ( ) dt% ' λd dt % ρ d t% , ρ d t% - n( , σ d ) and we write . the probability m is merely an empirical average over an infinitee m[dt% | dt] ' λd dt sequence of regimes.we now turn to a bayesian inference about the true probability Π. in a standard bayesian environment an agent faces data generated under a stationary structure but with an unknown and fixed parameter. the agent starts with a prior on the parameter and then uses bayesian inference for retrospective updating of his belief. the term “retrospective” stresses that inference is made after data is observed. in real time the agent must use the prior to forecast all variables while learning can only improve future forecasts of these variables. our model has some parameters fixed and others that change over time. the fixed parameters are known as they are deduced from the empirical frequencies. the time varying parameters, reflecting the non stationarity of the economy, are modeled by the fact that under the true probability Π the value hasdt a transition function of the form . dt% & λd dt ' bt % ρt% the sequence of parameters is an exogenous, time varying mean value function. agents know bt λd but not the “regimes” bt. this formulation includes economies with slow changing regimes, each lasting a long time or fast changing regimes. the mere fact that they change limits the validity of bayesian updating. to see why observe that at date t our agent has a prior belief about bt with which he forecasts . after observing he updates his prior to have a sharper posterior estimate of bt.dt% dt% but when date t+ arrives he needs to forecast and for that he needs a prior on bt+ . agents dodt% not know if and when a parameter changes. if the bt change slowly, a sharp posterior estimate of bt (given ) may serve also as a prior belief about bt+ . indeed, if the agent knew that thedt% bt ' bt% updated posterior of bt is the best prior of bt+ . in the absence of such knowledge, agents would believe that is only one possibility. they would, then, seek additional information and usebt ' bt% subjective interpretation of other public data to arrive at alternative subjective estimates of tobt% supplement the bayesian posterior they have. such subjective interpretation of public data arises naturally from the fact that public quantitative data is always provided together with a vast amount of qualitative information which is an important source of subjective interpretation of data. . . qualitative information and subjective interpretation of public information bayesian inference is only possible with quantitative measures. the fact is that quantitative data like are always accompanied with much qualitative public information about usual or unusualdt conditions. for example, data on inflation are interpreted with reports on normal or abnormal productivity features, conditions of the labor markets, assessment of the price of energy, political environment, etc. if are profits of a firm then is just one number extracted from a detaileddt dt financial report of the firm, the industry, the technology or the products involved. if are profits ofdt the s&p then qualitative information includes general business conditions, monetary policy, political environment, prospective tax reform, trends in productivity and other macroeconomic conditions. qualitative information cannot, in general, be compared over time and does not constitute conventional “data.” for example, when a firm announces a new research into something that did not exist before, no past data is available for comparison. when a new product alters the nature of an industry, it is a unique event. financial markets pay a great deal of attention to qualitative announcements which are often the focus of diverse opinions of investors. there is little modeling of deduction from qualitative information. saari ( ) uses qualitative information in a competitive model of market shares. toukan ( ) is a second example. here we provide a simple formalization of the use of qualitative information. thus, qualitative information consist of statements about the future. let date t statements be ,at '(at ,at ,...,atkt ) each with quantitative measures in some units. the list may change with t and varies with time.kt the activity in a statement may turn out to impact or not. the effects may be desirable(dt% &λd dt) or not. a realization at t+ is a vector of numbers which are or . a nt% '(nt% , ,nt% , ,...,nt% ,kt ) means the activity turns out to have no effect and means it has an effect. these can be interpreted as “success” or “failure.” there are possible vectors of outcomes . next, kt nt% (k) , k' , ,..., kt agent i has a subjective map from to an expected value of . this is annt% Φ i(nt% ) (dt% &λd dt) independent estimate by agent i on how different he expects to be from the stationary(dt% &λd dt) forecast conditional upon the success or failure of the statements. but, keep in mind, the quantitative estimate depends upon the statement . for example, a research plan with $ million budgetΦi(nt% ) at would be expected to have a smaller impact than a plan with a $ billion budget. finally, conditional on , agent i attaches probabilities to the vectors . the result of this is thatat (a i , a i , . . . ,a i k t ) nt% (k) agent i has an alternate subjective estimate of based only on public data :(dt% &λd dt) at .Ψ i t( at ) ' j k t k ' a i k Φ i(n i t% ( k )) by ( ) the long term average of is zero. hence, rationality requires that the are zero( dt% & λd dt ) Ψ i t mean random variables. although public data consist only of , the procedure outlined shows that indt a complex world agents endogenously create subjective quantitative measures which reflect their beliefs. we incorporate such a measure in the bayesian procedure below. . . a bayesian inference: beliefs are markov state variables start by assuming that has a true transition of the formdt% .d t% & λ d d t ' b t % ρ d t% , ρ d t% - n( , β ) agents do not know bt but β is known. at first decision date t (say, t = ) an agent has two pieces of information. he knows and observes qualitative information with which todt (a(t) ,a(t) ,...,a(t)kt ) assess . assume that without the prior subjective mean at t = is b but to start the process heΨ i t Ψ i t uses both sources to form, as yet unspecified, a prior belief about bt (used to forecaste i t ( bt | dt ,Ψ i t ) ). the changing parameter leads to a problem. when is observed, agent i updates hisdt% bt dt% &λd dt note our notation. we use the notation of for date t prior belief about the parameter used toe it ( bt | dt ,Ψ i t ) bt forecast . we then use the notation for the posterior belief about the same given the observation of dt% e i t% ( bt | dt% ,Ψ i t ) bt dt% but without forming the estimate of . assumption (a) will use this posterior belief as a building block in the formation of theΨit new prior about the new parameter .e it% ( bt% | dt% , Ψ i t% ) bt% belief about the same parameter to in a standard bayesian inference but beforebt e i t% ( bt | dt% ,Ψ i t ) knowing the assessment .the point is that the agent needs an estimate of , not of . hence,Ψ i t% bt% bt his problem is how to go from to a prior of ? without new information hise i t% ( bt | dt% ,Ψ i t ) bt% belief about is unchanged and he would use as a prior of . this is surely truebt% e i t% (bt | dt% ,Ψ i t) bt% if the b’s change very slowly or when . hence, if agent i believes a new prior isbt% 'bt bt% …bt needed. to that end he uses the qualitative information released publicly(a(t% ) , a(t% ) , . . . , a(t% )kt% ) before trading at t+ . these lead to an alternate subjective estimate of . now the agent hasΨ i t% bt% two independent sources for belief about : the last posterior is to be used if bt% e i t% ( bt | dt% ,Ψ i t ) and if . with a bayesian approach we assume:bt% 'bt Ψ i t% bt% …bt assumption (*): agent i uses a subjective probability to form date t+ prior belief which is thenμ ( a) .e i t% ( bt% | dt% ,Ψ i t% ) ' μe i t% ( bt | dt% ,Ψ i t ) % ( &μ)Ψ i t% # μ < at t= it was assumed an initial posterior b, hence for consistency, if is normal thenΨi ( b) for some α.b -n(μb%( &μ) Ψ i , α ) this assumption is the new element that permits the posterior of to be upgraded to ae it% ( bt | dt% ,Ψ i t ) bt date t+ prior belief about , before is observed. we then have:e i t% ( bt% | dt% , Ψ i t% ) bt% dt% theorem : suppose , i.i.d. and assumption (*) holds. then for large values of t, theΨ i t - n( , γ ) prior belief is a markov state variable such that if we define ande i t ( bt | dt ,Ψ i t ) g i t ' e i t ( bt | dt ,Ψ i t ) for some then the dynamics ( ) holds: ( a) implies ( ).μ κ ' λz < κ < proof: pick a starting date t = . data is known and the agent generates a subjective measure ofdt . he then forms a prior on , which by assumption (*) is . now weΨit bt bt-n(μb%( &μ) Ψ i t , α ) move on to t+ and dt+ is observed. the agent updates the prior in a standard bayesian manner: .e i t% ( bt | dt% , Ψ i t ) ' α (μb%( &μ) Ψ i t ) % β[ dt% &λd dt] α % β , #μ # but before date t+ trading he generates the subjective measure of qualitative data. byΨit% assumption (*) the expected parameter bt+ under the new prior at t+ is .e i t ( bt% | dt% ,Ψ i t% ) ' μ e i t ( bt | dt% ,Ψ i t ) % ( &μ )Ψ i t% , #μ # denote by . then the prior is ζ ' μ and ξ ' ( &μ ) .b t% - n( e i t ( bt% | dt% ,Ψ i t% ) , ζ (α%β ) % ξγ ) it is used to forecast . moving on to t+ , the agent observes and based on thisdt% &λd dt% dt% &λd dt% observation he uses bayesian inference to deduce a posterior belief about bt+ .e i t% ( bt% | dt% ,Ψ i t% ) ' (ζ (α%β )%ξγ ) [ μ e i t ( bt | dt% ,Ψ i t )%( &μ )Ψ i t% ] % β[ dt% &λd dt% ] ζ (α%β )%(ξγ % β ) before the start of date t+ trading, the agent generates a new value leading to t+ prior beliefΨit% about the unobserved parameter bt% e i t% ( bt% | dt% , Ψ i t% ) ' μ e i t% ( bt% | dt% , Ψ i t% ) % ( &μ ) Ψ i t% , #μ < when is observed the posterior belief about is thendt% &λd dt% bt% .e i t% (bt% | dt% , Ψ i t% ) ' [ζ (α%β)%(ξγ%β)j n' ζn&β][μe i t% (bt% | dt% ,Ψ i t% )%( &μ)Ψ i t% ]%β[dt% &λddt% ] ζ (α%β)%(ξγ%β)j n' ζn next the agent generates a new value leading to a t+ prior belief about .Ψit% e i t% ( bt% | dt% ,Ψ i t% ) bt% by forward iteration we conclude that after n rounds the prior takes the form e i t%n ( bt%n | dt%n% ,Ψ i t%n ) ' [ζn& (α%β)%( ξγ%β)j n& n' ζn&β] ζn(α % β)%(ξγ%β)j n& n' ζn [μe i t (bt%n& | dt%n , Ψ i t%n& )%( &μ) Ψ i t%n] % + . β[ dt%n% &λd dt%n ] ζn(α%β) % ( ξγ%β) j n& n' ζn now take the limit. since , as n increases hence we find that ζ > ζn lim n [ζn& (α%β)%( ξγ%β)j n& n' ζn&β] ζn(α % β)%(ξγ%β)j n& n' ζn ' (α%β)%( ξγ%β) ( ζ ζ & ) ζ (α % β)%(ξγ%β)( ζ ζ & ) / κ some (e.g. bacchetta and van wincoop ( b)) bypass this theorem by not carrying out the full inference and instead making the arbitrary assumption that the information structure in a noisy ree is of finite memory. since all terms are positive it is clear that < κ < . hence we have that for large t e i t% ( bt% | dt% ,Ψ i t% ) ' κ[μ e i t ( bt | dt% , Ψ i t ) % ( &μ )Ψ i t% ] but by definition we have ( ) e i t% ( bt% | dt% , Ψ i t% ) ' μ e i t ( bt | dt% ,Ψ i t ) % ( &μ )Ψ i t% we conclude that for large t, the contribution of each new observation of dividends is negligible hence .e i t ( bt | dt% ,Ψ i t ) ' κe i t ( bt | dt ,Ψ i t ) inserting this last equation again into ( ) we finally have the desired conclusion that for large t ( ) .e i t% ( bt% | dt% , Ψ i t% ) ' μ κe i t ( bt | dt , Ψ i t ) % ( &μ ) Ψ i t% now identify , and to see that ( ) is actually ( ). �g i t ' e i t ( bt | dt ,Ψ i t ) ( &μ)Ψ i t% ' ρ ig t% μκ ' λz the theorem shows that as the dt data set increases, there is nothing new to learn. the posterior does not converge but the law of motion of the posterior converges to a time invariant stochastic law of motion defined by ( ). the posterior fluctuates forever, providing the basis for the dynamics of market belief but the fluctuations follow a simple markov transition. new data dt and alter theΨ i t conditional probability of the agent, but these do not change the dynamic law of motion of . g i t . contrasting the models: pi vs. hb we discussed in section the natural objections to an excessive use of the assumption of pi. we now complete the comparison between the two theories and their empirical implications based on the analytic results of the two models. we also return to the notation of the earlier model. . sharp differences in asset pricing implications the striking difference between the two theories are revealed by their equilibrium price maps. hence they lead to different characteristics of all phenomena which depend upon price dynamics, such as market volatility, risk premia, etc. we thus examine the difference between the maps ( a)-( c) under pi and ( a)-( d) under hb. prices ( a)-( c) under pi have infinite memory, a generic property of any learning. this follows from a theorem which says that if some components of a markov process are unobserved, the process without full observability becomes one of infinite memory . since learning in a noisy ree with pi is driven by unobserved supply shocks, the inference utilizes all past prices which are proxies for these shocks. the infinite memory of prices arises despite the fact that the exogenous shocks have no memory at all. in addition, since private signals are independent they are averaged out and the average equals q, the true value. hence under pi price dynamics, risk premia and all other endogenous phenomena which depend upon prices are driven only by market “fundamentals”: changes in qt and past supply shocks , all of which are unobservable. indeed, noisy rees t ' ( s , s , . . . , st ) under pi leads to the peculiar result that prices depend on variables which nobody observes. in contrast, the asset pricing theory under hb leads to an invariant price map which is defined over the economy’s state variables, including the market state of belief, all of which are observable. hence, the pricing process is non-stationary only to the extent that state variables are non stationary. under hb the price does not reflect the unknown intrinsic value of the object since no one knows it and pt forever fluctuate around their “fundamental” values. but there is a deeper principle involved here which is orthogonal to any rational expectations thinking. in a market with hb agents never learn the true structure of the economy and this leads to a simple principle. in an equilibrium with hb there is one true stochastic law of motion of state variables but traders hold diverse beliefs about this dynamics. hence, most traders are wrong most of the time. hence, under hb prices are determined by the distribution of forecasting mistakes of the traders. indeed, prices are functions of both the observed exogenous variables as well as the market’s belief about the future. but the market belief is the aggregation of individual assessments, including all mistaken assessments. as a result, under hb the price space is larger than under pi and price volatility is greater than the volatility implied by exogenous shocks. kurz ( ), ( a) and kurz and wu ( ) call this component of market risk “endogenous uncertainty.” samuelson expressed the intuition of this formal result by noting that “the market has predicted ten of the last six recession.” recall under hb agents do all the learning they can from past data and past data is ample, hence both heterogeneity and price volatility are persistent. . difference in beauty contest implications a great deal has been written about the keynesian beauty contest metaphor. in the context of the pi model with n rounds of trading one can rewrite ( c) in the form p ' ē ē . . . ēn( q ) & var ( p ) τ s allen, morris and shin ( ) associate this equation with the beauty contest since in a noisy ree the price today reflects tomorrow’s (i.e. next round) average market forecast of the fundamental value q. this is much too narrow interpretation of the “beauty contest.” an examination of this idea, as explained by keynes (see keynes ( ), page ), shows that the crux of keynes’s conception is that there is little merit in the idea of using fundamental values as a yardstick for market valuation. hence what matters for the market pricing of an asset is what the market believes the future price of that asset will be rather than what the intrinsic value of the asset will be. moreover, keynes insists future price depends upon future market beliefs which may be right or wrong but have no necessary relation to fundamental values. hence, one must interpret the “beauty contest” as keynes’ statement that the price today is determined by today’s market belief about the forecasts of the market’s investors tomorrow, when such forecasts may be “right” or “wrong.” the allen, morris and shin ( ) interpretation does not rise to this level of subtlety required of the “beauty contest” idea. finally, the idea of “trading rounds” is a modeling construct and as the number of rounds increases the private information market leads to full revelation hence, with time, p = q. when this is the case, traders do not engage in any “beauty contest”at all, which makes any “beauty contest” temporary. another line of thinking in the literature about the beauty contest often stresses the role of higher order expectations. this is entirely misleading since higher order expectations are intrinsic mathematical properties of a probability measure over future sequences. indeed, conditions ( a)-( b) imply iterated higher order expectations and this is true with and without pi or hb (see also townsend ( ),( )). the idea that higher order beliefs “are important” in some sense is no more than the statement that investors hold probability beliefs about future sequences. we now examine the hb perspective of the beauty contest, keeping in mind the fact that the unknown value qt is announced at the end of each date. to enable full comparison with the pi model suppose for the moment that we discard the hedging demand and assume our traders are short lived. in that case demand function ( c) would apply and we would write it in the dynamic context as\ ( a) .pt ' ēt( pt% ) & g τ s insert into ( a) the corresponding equilibrium map under hb which would remain of the functional form ) to havept% 'ĉ ( qt%μ )%ĉ zt% &ĉ s ( b) .pt ' ĉ ( ēt [ qt ] % μ ) % ĉ ēt [ zt% ] & (ĉ % g τ ) s compare ( b) with the price maps ( a)-( b) under pi which depends upon q and the supply shocks p ' κ ( λ y % μ q & s ) .p ' κ̂ ( λ̂ y % μ̂ q & s % ψs ) in ( b) the price at t is a function of the market expectation of qt and of zt+ , the market belief state at date t+ . the crux of the hb theory says that the root causes of endogenous uncertainty are the mistakes markets make in pricing assets too high or too low, leading to excess volatility. the term in the price map ( b) says the price today depends upon today’s risk perception of theēt [ zt% ] mistaken assessment the market may collectively make tomorrow. this risk is central to any theory with hb. this, in our view, is the essence of the keynesian beauty contest. in short, the difference between the pi and the hb perspectives of the beauty contest is very sharp. under pi the price is a function of the true fundamental value which is unknown to anyone. under hb, the price depends upon the market expectation of qt and and of zt+ . but market belief may be right or wrong hence it may cause the asset to be overpriced or underpriced. this fear of future price volatility induced by future market beliefs, which we call “endogenous uncertainty,” is therefore at the heart of the “beauty contest” phenomenon. . difference in rationality assumptions and restrictions: rational beliefs up to now we compared the pi model with the hb model without specifying any restrictions on information or requiring restrictions on beliefs. we criticized the pi theory for permitting arbitrary, unobservable, private signals and introducing contrived random supply shocks. these make it possible to prove anything with a model with pi. one may make a similar argument against hb, claiming that with hb one can prove anything. this last argument is false for two reasons. first, since the distribution of market belief is observable, hypotheses about the impact of market beliefs are testable. second, we have defined individual beliefs to be about deviations from the empirical distribution and this, by itself, places restrictions on beliefs. indeed, it is essential that we seek additional a priori restrictions on beliefs in order to further narrow down the empirical implications of the theory given the specified information. recall that at t trader i knows his own but he does not observe any past values of for all( g i t , g i t& ) g k τ k. he does observe the distribution of for all dates up to t. this is an assumption of anonymity. g k τ the theory of rational belief (in short, rb) due to kurz ( ), ( a) proposes natural restrictions on beliefs. in a sequence of papers the theory has been applied to various markets (e.g. kurz ( ), ( a), ( b), kurz and schneider ( ), kurz and wu ( ), kurz, jin and motolese ( b), motolese ( ), ( ) nielsen ( ), ( ), wu and guo ( ), ( )). in relation to the equity risk premium, kurz and beltratti ( ), kurz and motolese ( ), and kurz, jin and motolese ( a) explain the equity premium by asymmetry in the distribution of beliefs. a belief is a rational belief if it is a probability model of the observed market variables which, if simulated, reproduces the known empirical distribution. an rb is thus a model which cannot be rejected by the empirical evidence. we specified beliefs with the perception models ( a) -( b). for these to be rb they must induce the assumed empirical distribution ( a)-( b). but this requires that ( ) the empirical distribution of = the distribution of λ g qg i t %ρ iq t λ g zg i t %ρ iz t% ρ q t ρ z t% -n , σ q, , , σ z , i.i.d. to compute the moments of the empirical distribution of the market variables ( qt& , zt ) implied by the model ( a) -( b), one treats the symmetrically with other random variables.g i t from ( ), the unconditional variance of isg i t .var( g i ) ' σ g & λ z hence, we have the following rationality conditions on the moments, which follow from ( ): (i) (ii) (iii) (λ g q ) σ g & λ z % σ̂ q ' σ q (λ g z ) σ g & λ z % σ̂ z ' σ z λ g q λ g z σ g & λ z % σ̂zq ' (iv) (v) . (λ g q ) λzσ g & λ z % cov(ρ̂ iq t , ρ̂ iq t& ) ' (λ g z ) λzσ g & λ z % cov(ρ̂ iz t , ρ̂ iz t& ) ' the first three conditions pin down the covariance matrix in ( a)-( b). the last two pin down the serial correlation of the two terms . an inspection of ( a)-( b) reveals the only choice left(ρ̂ iq t , ρ̂ iz t ) for a trader are the two free parameters . but under the rb theory these are not completely(λ g q , λ g z ) free either. the requirements that place two strict conditions on :σ̂ q > , σ̂ z > (λ g q , λ g z ) .|λ g q | < σq σg & λ z |λ g z | < σz σg & λ z next, to ensure the covariance matrix in ( a)-( b) is positive definite one must impose an additional condition. a condition such as & λ z σ g > (λ g z) σ z % (λ g q) σ q is sufficient. finally, if one accepts the bayesian procedure in section . as the basis for ( ), one can also insist on the restriction , but this restriction does not flow from the basic rb condition.λ g q ' within the bayesian framework we would also insist that the time average of the distinct valuations under qualitative assessment be zero as they would measure only deviations from the stationary forecast. we then see that the "free" parameters are restricted to a rather narrow range.(λ g q , λ g z ) . difference in testable implications in section we explored the assumptions of the pi theory. since neither the private signals nor the supply noise are observable, the pi theory lacks testable implications. the model’s key implication is the price map which results from the informational assumptions which are contrived and implausible. in contrast, the model under hb is entirely testable since all central components of the theory are observable, including the average market belief. data on the variables zt are constructed exactly as required by averaging ( ). in a standard asset pricing equilibrium one can then write down the euler equations of the agents, aggregate them and use the market data on returns, asset prices and market beliefs for a full identification. recent examples of work where this has been done include fan ( ) and kurz and motolese ( ). these papers show that with data on asset returns and market belief an asset pricing theory leads to specific testable restrictions. moreover, by studying the excess returns on different categories of assets (i.e. stocks, bonds, etc.) one derives sharp estimates of the market risk premia of different assets and the effect of market beliefs on such premia. clearly, the empirical evidence is the decisive factor to reveal which of the two theories discussed here is superior. references allen, f., morris, s., shin, h.s. 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(ed.) knowledge, information and expectations in modern macroeconomics, in honor of edmund s. phelps princeton: princeton university press. economics blog - blog about finances, economics and money skip to content economics blog blog about finances, economics and money menu home finance loans insurance credit cards savings contact search why is there no credit check with payday loans? people often suggest that, as payday loans are advanced without credit checks, the lender is acting irresponsibly loaning out money carte blanche without doing background checks first. whilst it’s true that most payday lenders are not so concerned with credit history, to say that they don’t carry out checks is something of a myth. twice […] loans read more look for unclaimed money – retirement benefits and k funds retirement funds from defined benefits plans are insured by the pension benefits guarantee corporation or pbgc. this is a government agency set up to protect employees’ pension money in case their companies go out of business or close their pension plans. retirement funds from k plans are not guaranteed by pbgc. however, k funds are […] finance unclaimed money read more accidents and injuries at work: how to avoid them and what to look out for knowing the risks surrounding you in the workplace can stop accidents and illnesses from occurring. there’s no doubt about it: sometimes, the workplace can be a real war zone. just in the past year, over a million people in the uk have been become ill as a result of doing their job, and workers […] finance injuries at work read more important lessons every young adult needs to learn about finances as parents, it’s important to make sure you pass on lessons to your children. unfortunately, too many financial lessons get forgotten along the way. because of this, young adults go out into the world, ignorant of crucial money lessons. so, what are some things that kids need to know about money? 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is money really that hard to manage? well, the answer to these questions is both yes and no. yes, because with the rising number of people caught up in the web of debt, even if they are earning sizable income, is proof that money is the most challenging thing […] finance financial advisor investment advisor read more recent posts why is there no credit check with payday loans? look for unclaimed money – retirement benefits and k funds accidents and injuries at work: how to avoid them and what to look out for important lessons every young adult needs to learn about finances protect yourself against the unthinkable with a popular cancer cover more financial related tips can be found on financialhelper.co.uk sÖz varliĞi turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bİr gazel karŞisinda sÜje veya …ÜstÜ okuma; sadece gÜzel resul kaya  Özet edebî bir eser karşısında tavrın ne olduğu tartışmalı bir konudur. tartışmanın merkezinde edebî eserin ne olduğu, bu eser karşısında süjenin özellikleri ve bunların süreçle olan ilgisinin hangi boyutta olduğu konuları vardır. diğer taraftan sanat eserinden oluşan hazzın güzel kavramıyla ilgisinin, derinliklerinin, sürekliliğinin olup olmadığı ayrı tartışma noktalarıdır. bu çalışmada edebî eser karşısında süjenin süreç içerisinde konumundan bahsedilip, sürecin bütün bir faaliyeti yöneten unsur olup olmayacağı görülmek istenmiş, sonrasında güzelin bütün bu tavrı nasıl yönlendirdiği vurgusu yapılmıştır. anahtar kelimeler: edebî eser, süje, süreç, güzel. suje before a gazzel or …higher reading: only beauty abstract what is the attitude towards a literal work is a controversial issue. at the centre of the controversy there are some basic concerns like what is a literal work, the characteristics of suje towards this work and how all these are affected by the process etc. on the other hand the depths and continuity of the relations between the pleasures emerged from the art work and the concept of beauty is another topic of discussion. in this work in order to see whether the process is the factor that manages the whole activity the position of suje during the process towards a literal work is going to be touched  arĢ. gör. balıkesir Üniversitesi, necatibey eğitim fakültesi türk dili ve edebiyatı eğitimi resulkaya_ @hotmail.com mailto:resulkaya_ @hotmail.com bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer upon then how the beauty affects this attitude is emphasized. key words: literal work, suje, process, beauty. giriş edebiyatla ilgili bir metinle ilk karĢılaĢma anında, sonrasında, metnin yaĢantının parçası olması süresi içinde süjenin düĢünce, hayal, ruh, reel dünyasında ne olup bitmektedir? bu anlamda süje için metin nedir, metin karĢısında süje nedir? böylesi baĢlayan bir süreç hangi boyutlara kadar gider? son sınır nedir? bu çalıĢmada yukarıdaki Ģekilde baĢlayan sürecin süjede nasıl devam ettiği göstergeleri sunulacaktır. baĢlayan böylesi bir sürecin devam edip etmeyeceği, devam ederse nereye kadar, nasıl devam edeceği bilinmemektedir. ÇalıĢmanın amacı bir sanat eserinin değerlendirilmesinde sürecin yöntem olarak kullanıp kullanılmayacağını belirleyebilmek veya sürecin yöntem oluĢturmada etkisinin olup olmayacağını görebilmek için bir zemin oluĢturabilmektir. süjede baĢlayan bu süreç Ģu an devam etmektedir. bu sürecin nasıl baĢladığı, Ģimdiye kadar nasıl devam ettiği ile ilgili tespitlerin öncelikle belirtilmesi gerekli görülüyor. metinle İlk karşılaşma Öncesi zihnî durum bu çalıĢmanın öncesinde -Ģimdi de olduğu gibi- edebiyatla ilgili metinlerin hangisinin sanat eseri olduğu ile ilgili belirlemenin süje tarafından yapılması gerektiği savunulmuĢtur. zira süjenin anladığı anlam özeldir. hayatın süjece yaĢanması gibi özeldir. nasıl genel bir hayat içerisinde kiĢi kendi hayatına özel bir anlam, özel bir varoluĢ özelliği veriyorsa kendi okuduğu bir metni anlamada da özel bir tutum takınmak ister. edebî bir eserin süjece algılanmasından, özellikle haz boyutunda algılanmasından öte ne vardır? sanat eserinin böyle anlam kazandığı, süjede anlam kazandığı düĢüncesi bir anda düĢünülmüĢ değildir. zaman içerisinde, bu düĢünce sürecinden karĢılaĢılan her metin bu anlamda payına düĢeni almıĢtır. bu düĢünceden hareketle bir edebî metnin ne anlama geldiğini, onun tam olarak ne olduğunu belirleyen unsurun süreç olup olmadığının pratikte gösterilip gösterilmeyeceği hep düĢünülmüĢ, resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer sürecin böylelikle yöntem olarak kullanılıp kullanılmayacağı hep merak edilmiĢtir. bu meraktan hareketle yukarıda bahsedilen süreç yönteminin edebî bir eserde uygulanıp uygulanmayacağı fikri zihinde kendiliğinden canlanıverdi. zihindeki bu canlanmanın hemen ardından edebiyat alanındaki metinlere bakılarak süjenin sürecinin nasıl iĢlediği görülmek istendi. Ġlk olarak ele geçen metinler okundu. bu metinler zihnî bir hazır bulunuĢluk olmadan rastgele okundu. okumalar sırasında süjenin metni kendi anlaması gibi diğer süjelerin de kendi süreçlerini nasıl yaĢadıkları merakı uyanıverdi. zincirleme olarak da bir metnin anlaĢılması için süjelerin katkısının ne olup olmadığı düĢünülüp, genel bir sürecin nasıl iĢlediğini görmenin iĢe yarar olabileceği heyecanı duyuldu. böylelikle genel bir sürecin nasıl iĢlediği görülebilirdi. bu sırada yeni bir süreci baĢlatmak mümkün olmadığından, önceden baĢlamıĢ bir sürece dâhil olmak gerektiği anlamlı göründü. zira yüzyıllardan beri birikerek gelen edebiyat dünyasının bir anlam geleneği vardı ve bu geleneği göz ardı etmek olmazdı. diğer yandan süjenin kendini anlam konusunda özgür hissetmesi gerektiği düĢüncesinden vazgeçilemiyordu. tam da bu sırada hem önceden baĢlayan bir sürece dâhil olunabileceği hem de süjenin kendi sürecini diğer yandan devam ettirebileceği akla geldi. bu noktada önceden ele alınmıĢ bir eser bulmak gerekliydi. bu ele almanın süje tarafından bilinmemesine dikkat edildi. zira süjenin edebî bir eserle ilk karĢılaĢmasında kendi özgün sürecini bir hazır bulunuĢluk olmadan baĢlatmasının uygun olabileceği düĢünüldü. bu ilk karĢılaĢma sonrası ele alınan çalıĢmaya bakılarak önceden baĢlayan sürece süje dâhil edilmeye çalıĢıldı ama önceden söylenildiği gibi süreç içerisinde diğer süjelerin iĢleyiĢi nasıl etkileyeceği bilinmemektedir. metinle İlk karşılaşma yukarıda söylenildiği gibi ilk olarak daha önce ele alınmıĢ bir metin bulmak gerekirdi. araĢtırmalar sırasında tahlil edilmiĢ değiĢik çalıĢmalara ulaĢıldı, bunların bir kısmı daha önce bilinen/okunmuĢ/anlamlandırılmıĢ olduğundan bir kısmının da tahlilleriyle okunmuĢ eserler olmasından dolayı tercih edilmedi. süje için ilk defa karĢılaĢılan bir metin olmalıydı. zira ilk okuma edebî bir metnin anlam ve haz boyutunda değerlendirilmesi için önemlidir. Çünkü süjenin sürecini baĢlatan ve nasıl bir süreç takip edeceğini belirleyen aslında bu ilk okumadır. diğer yandan ilk karĢılaĢılan bu metnin önceden ele alınmıĢ olması gerekliydi. böylelikle hem önceden baĢlayan bir sürece dâhil olunabilir hem de ilk okumanın bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer süjede nasıl bir süreci baĢlattığı görülebilirdi. genel süreç ve bu sürecin içinde süjenin sürecinin özellikleri tespit edilebilirdi. bu düĢünceler doğrultusunda araĢtırmalar sırasında “kadı burhaneddin’in bir gazelinden hareketle” baĢlıklı çalıĢma dikkat çekti. bu çalıĢmaya konu edilen Ģiirin okunmasıyla süjedeki süreç baĢlamıĢ oldu. ÇalıĢmaya konu edilen Ģiir aĢağıdaki gibidir: ġâhâ senüñ camâlüñi göreyim andan öleyim susamıĢam visâlüñe ireyim andan öleyim bunca zemân lebünçün saçuñ karañusındayım Âb-ı hayât kandadur sorayım andan öleyim dün gice düĢde ben seni benümile göriridüm bu düĢümün ta’bîrini yorayım andan öleyim bezm-i ezelde ireli cânuma aĢkı hüsnünüñ Ġrimedim varamadım ireyim andan öleyim canum u aklum u göñül zülfüñ içinde yitdiler teĢvîĢ eğer olmazısa tarayım andan öleyim metni İlk okuma ġiirde Ģairin belirli isteklere kavuĢma dileğinde bulunduğu anlaĢılmaktadır. ġair, Ģiirinde bahsettiği isteklere kavuĢtuktan sonra ölmek istediğini belirtiyor. ġiir boyunca da bu isteklerini sıralıyor. ġiir boyunca Ģair birisine hitap etmektedir. hitap ettiği kiĢi ikinci tekil Ģahıstır. ġairin istekleri de yine bu ikinci tekil Ģahısla ilgilidir. bu Ģahsın özelliklerinin ne olduğu, kim olduğu konusunda bir netlik yok. karĢısındaki kiĢiye “ġâhâ” diye seslense de bu kiĢinin gerçekten Ģah mı olduğu, Ģairin gönlünün Ģahı mı olduğu, Ģahtan kastının yaratıcı mı olduğu soruları akla geliyor. “senüñ camâlüñi göreyim” derken Ģahın kim olduğu noktasında ipuçları var gibi. yaĢarken yüzünü görmek istediği varlığın bu anlamda yaratıcı olamıyacağını buradan çıkarabiliriz. zira yaratıcının yüzü yaĢarken somut anlamda görülemez. geriye yüzünü görmek istediği kiĢinin atabey kılıç, “kadı burhaneddin’in bir gazelinden hareketle”, klâsik türk edebiyatı Üzerine makaleler, turkish studies publication, ankara, , s. – . araĢtırmalar sırasında karĢılaĢılan çalıĢmaya konu edilen Ģiirdir. dolayısıyla Ģiir, çalıĢmada verildiği Ģekilde buraya alınmıĢtır. resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer insan olduğu ihtimali güçlü olarak kalmaktadır ki bu insanın da kim olduğu hâlâ meçhuldedir. ġairin karĢısındaki kiĢiyi tek bir defa mı görmek isteyip istemediği, ilk mi, son mu görmek isteyip istemediği bu meçhullüğü artırmaktadır. ġair, “seni son kez göreyim, seni bir defa göreyim” gibi ifadeleri kullanmıĢ olsaydı belirsizlik ortadan kalkacaktı. ġiir boyunca Ģairin hitap ettiği kiĢinin tam olarak kim, ne olduğu belirsizliği devam etmektedir. ġairin karĢısındaki kiĢinin dudaklarını öpmek istemesi, onu rüyasında görmek istemesi bu kiĢiden kastının sevgili olduğunu akla getirse de “bezm-i ezel”den beri karĢı tarafla aĢinalığının olduğunu belirtmesi Ģiirde dinî anlamların olabileceğini düĢündürmektedir. Şiirin Şerhinin/ açıklanmasının/yorumunun/Çözümünün/ okunması daha önce bahsedildiği gibi baĢlayan bir genel sürecin içerisine süje dâhil edilmek istenmiĢ dolayısıyla ilk okuma sonrası Ģiirin Ģerhi okunmuĢtur. (bu Ģerhin okunmasıyla sürecin nasıl devam ettiği ilerde gösterilmiĢtir.) yukarıdaki Ģiirin Ģerhi daha önce atabey kiliÇ tarafından yapılmıĢtır. atabey kiliÇ, çalıĢmasında Ģiirin Ģairi hakkında kısaca bilgi verdikten sonra bir Ģiiri yorumlamadaki güçlüklerden, özellikle Ģiire herhangi bir sıfatı vermenin güçlüğünden bahsederek Ģiir karĢısında nelere dikkat edileceğinin standardı olmadığını belirtir. bir Ģiiri yorumlamada eklektik tavrın büyük ihtimalle anlamaya yararlı olabileceğini ifade ederek çalıĢmasında konu edindiği Ģiirle ilgili kendi düĢüncelerini aktarmak niyetinde olduğunu vurgular. metni “baĢkalarından daha iyi” anladığı iddiasında olmadığını özellikle vurgulayan kılıç’ın Ģiir karĢısındaki düĢünceleri Ģöyledir: “ey hükümdar senin yüzünün güzelliğini göreyim de ondan sonra öleyim. sana kavuşmaya susamışım, ulaşayım da ondan sonra öleyim” Ģeklinde aktarabileceğimiz matla beyti görüleceği üzere dînî birtakım telmihler taĢımaktadır. anahtar kelimelerden olan “cemâl”, allah’ın yüz güzelliği “cemâl-i mutlak” karĢılığındadır. kitab’ın anlattığına göre biz cemâl-i mutlak’ı ilk kez “elest bezminde” görmüĢüz. Ġkinci görüĢ ise mîzandan sonra Ģâyet cennet nasip olur ise söz konusu olabilecektir. sadece bu telmihten dolayı klâsik Ģerh usûlünde düĢünecek olursak sayfalar tutacak mâlumâtı sıralamamız mümkündür. klâsik kültüre âit, pek çok kiĢinin rahatlıkla tahmin edebileceği bu bilgiler, muhtemelen Ģairin de bilgisi dâhilindedir. atabey kılıç, age, s. – . bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer buradan en az Ģair kadar okuyucun da bu beytin arka plânında bulunan bilgilere vâkıf olması gerektiği anlaĢılacaktır. Ġkinci mısrada da “visâl” kelimesi anahtar olarak bulunmaktadır. visâlin dünyevî anlamından ziyâde dînî anlamının ağır bastığını rahatlıkla söyleyebiliriz. bu konuda da sayfalar dolusu bilgi aktarmak mümkündür. eklemek istediğimiz son bir husus, hz. peygamber’e atfedilen “Ölmeden önce ölünüz” meâlindeki ifâdenin hem beyitle, hem de Ģiirin bütünüyle ve redifle doğrudan alâkasıdır. nefis terbiyesi esâsına dayanan bu veciz ifâde, kâmil insan olmanın öncelikle mâsivâ yani allah’tan gayrı her Ģeyden geçmek Ģeklinde kabaca özetlenebilir. cemâl-i mutlak’ı görmek için, vuslata ermek için önce nefis terbiyesi yapmak gerekir. beyitteki zıtlık, Ģairin ölümü Ģarta bağlamasıdır: önce cemâl, visâl, sonra ölüm. Ölmeden önce ölmek, tasavvuf terimleri ve deyimleri sözlüğünde “kalpte, allah’tan gayrı bütün istekleri yok etmek. bu, isteğe bağlı (irâdî ölümdür); mecbûrî ölüm (son nefesle ölüm ) değildir. bu şekilde kendi irâdesiyle ölenler ma’nâ âleminde yeni bir yaşantıya kavuşurlar. Âb-ı hayât denilen ölümsüzlük suyu da işte budur.” Ģeklinde tarif edilmektedir. beyitten de kadı burhaneddin’in âb-ı hayât peĢinde olduğunu yani mâ’nâ âleminde yeni bir hayata kavuĢmayı arzuladığını anlamak mümkündür. Ġkinci beyit zaten bu fikrimizi destekleyen güçlü bir delildir. yunus emre’nin “Âşıklar yoldaş olup sâdıklara yâr olmadun Ölmezdin öndin ölmedin ışk neylesün senün ile” beytinde de anlatmaya çalıĢtığı Ģey aĢktır. kadı burhâneddin’in yukarıya aldığımız gazelinde aĢk kelimesi bir defa geçmektedir. fakat Ģiirin tamamında ortak konu aĢktır, daha doğrusu Ġlâhî aĢktır. biz sözü daha fazla uzatmadan temas etmeyi düĢündüğümüz dördüncü beyte göz atmaya çalıĢalım. “ezel meclisinde senin güzelliğinin aşkı, ruhuma ulaştığından beri ( ben sana) eremedim, varamadım; ulaşayım ondan sonra öleyim. ” beytin anahtar kelimesi “bezm-i ezel” dir. kur’ân-ı kerîm’de a’raf suresi . âyette anlatıldığına göre ruhlar âleminde cenâb-ı hak bütün ruhlara “elestü bi-rabbiküm (ben sizin rabbiniz değil miyim?)” diye buyurunca, hepsi birden “belâ (evet) ” Ģeklinde cevap vermiĢler ve bu yolla ruhlar, kıyamet günü “biz bundan habersizdik.” dememeleri için birbirlerine Ģâhit tutulmuĢlardır. ku’ân- ı kerîm’de anlatılan bu sahneye sûfîler “bezm-i elest” veya “bezm-i ezel” de demiĢlerdir. kadı burhâneddin de bu meclise iĢaret etmekte ve bütün ruhların cenâb-ı hakk’ı ilk kez görüp âĢık oldukları o âna telmihte bulunmaktadır. can kelimesinin arapça ruh anlamında olduğunu hatırlatırsak, aĢk ve hüsn kelimeleriyle bezm-i ezel terkibi resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer de bu sahneyle ilgili telmihi pekiĢtirir. Ġkinci mısradaki irimemek, varamamak ruhlar âleminden sürgünlüğümüzün ifâdesidir. sûfilere göre mâlum olduğu üzere bizler allah’ın huzurundan dünya hapishânesine gönderilmiĢ bulunmaktayız. ruhumuz da ten kafesinin içerisine hapsedilmiĢtir. bu dünyada iken allah’ın hüsnünün aĢkına eremememin, varamamamın pek çok sebebi vardır. sûfî terminolojisinde kesrette kalmak ya da mâsivâdan geçememek diye adlandırılan bu hâl yunus’un ifadesiyle “hayvan” olma hâlidir. Ġrmenin, varmanın anahtarı âĢık olmaktır veya âĢıklık hâlidir. yine yunus’un ifadesiyle “Ölen hayvandurur âĢıklar ölmez”. ÂĢık olmak için ise, öncelikle dünyadan, bedenden ve allah’ı unutturacak her Ģeyden vazgeçmek gerekir. pek çok tarikatin, tarikate kabul merâsimindeki sembolik “baĢ kesme âyini” iĢte bu, allah’ı unutturacak her Ģeyden vazgeçmeye olan arzuyu da gösterir. yani böylece, hayvan olan kısım gidecek, “âĢık”(insan) olan kısım ortaya çıkacaktır. bu yolla baĢ gözü kapanacak, kalp ya da gönül gözü açılacak; baĢ dili kesilecek, kalp veya gönül dili açılacak ve nihâyet baĢ kulağı kapanacak, can kulağı açılacaktır. bu Ģekilde nefis sembolik de olsa öldürülecektir. mûtû kalbe en-temûtu yani, “Ölmeden önce ölünüz.” beĢ beyitlik bu gazele baktığımızda öncelikle ön planda hemen herkesin rahatlıkla anlayabileceği dünyevî veya sığ bir mânâ bulunur. fakat kelimelerin sıralanıĢına, ikinci, üçüncü anlamlarına biraz daha dikkat edildiğinde görülecek ola Ģiire asıl değerini veren arka plândır. burada Ģiirin tamamına hâkim olan dînî ve daha doğrusu tasavvufî tablolar görürüz. bütünlüğe dikkat edildiğinde, elest bezminden baĢlayıp dünyadaki, insan-ı kâmil olma mücâdelesini de içine alan insan hikâyesini görürüz. elhak nefsini bilen rabbini de bilir. klâsik kültürün çok önem verdiği kâmil insan olma gayreti, günümüzde belki anlaĢılmaktan bile çok uzaktır. biliyoruz ki bu kültüre dâhil olan atalarımız hangi meslekten, milletten ve meĢrepten olurlarsa olsunlar, Ģöyle böyle bu gayretin içerisindedir. tabiîdir ki kadı burhâneddin de kültürümüzün anadolu sahasındaki oluĢumunda hizmetleri bulunan önemli bir kiĢi olarak bu gayrete yabancı değildi. aldığı dînî eğitim, büyük ihtimalle, Ģiirlerinde gördüğümüz tasavvufî söylemleri de beslemiĢtir. sözü daha fazla uzatmadan sadece bu gazelden hareketle kadı burhâneddin’in Ģiirlerinde dinî alt yapının fazlasıyla bulunduğunu söylememiz mümkündür. fakat bu yönün tasavvufî sıfatı ile nitelendirilip nitelendirilmeyeceği hususunda tereddütlerimiz vardır. Öncelikle bu son sıfatın bütün devirler, isimler, meslek ve meĢrepler göz önünde bulundurularak sağlam bir tarifinin yapılması lâzımdır. tasavvufî Ģiiri, bir tarikat veya tekkeye mensup kiĢilerce yazılmıĢ dînî nitelikli Ģiirler olarak kabaca kabul edecek bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer olursak, hakikati belki de sadece bir yönünden tutmuĢ oluruz. bu hâlde kadı burhâneddin’in Ģiirlerine tasavvufî sıfatını vermek söz konusu olamaz. dînî içerikli Ģiirlerin hepsine tasavvufî sıfatını yapıĢtıracak olursak, o zaman edebiyatımızda bütün devirler içerisinde bu anlamda dînî olmayan Ģiir yazmıĢ birkaç isim kaldığını görürüz. hâl böyle olunca terimlerin içini doldurmanın ne kadar mühim olduğu kendiliğinden ortaya çıkmaktadır. netice itibarıyla Ģiiri anlama hususunda bize kalan, Ģu meĢhur ifâdeye sığınmak olacaktır: “el-mâ’nâ fî-batni’Ģ-Ģâir”. mânânın da “sırr-ı ekber” veya “âĢikar sır” olduğunu tekrar edersek bir metni anlamanın ne kadar güç olduğunu tekrara herhâlde lüzum kalmayacaktır.” Şerhten/açıklanmadan/yorumdan/Çözümden hareketle okumayla akla gelen sorular ġaha kelimesinden yaratıcının anlaĢılmasının nedeni nedir? Ġlk okuma baĢlığı altında söylendiği gibi Ģah tamamen Ģairin hayal dünyasında veya kendi dünyasında mevcut biri, sadece Ģairin bildiği biri, çok özel biri olamaz mı? bundan hareketle Ģair bu Ģiiri herhangi bir yere yazıp Ģah dediği kiĢiye doğrudan veya dolaylı olarak ulaĢtırmıĢtır diyemez miyiz? bu Ģiirin ne amaçla kime yazıldığı konusunda elimizdeki bilgiler ne kadardır? yaratıcıya yönelik dua, istek varsa ve bu da Ģiirde hakim olan duygu, düĢünce ise neden Ģair seslenme ünlemlerini çok kullanmamıĢtır? neden sadece “Ģaha” kelimesiyle seslenmiĢtir? bu durum diğer taraftan yaratıcı dıĢında hitap edilebilir kiĢiler-varlıklar için de geçerlidir. “susamıĢam visalüne” ile baĢlayan mısra güçlü bir duyguyu vermesi açısından seslenilenin yaratıcı olduğu düĢünülebilir. zira ancak yaratıcıya böylesi bir duygu beslenebilir. diğer yandan Ģairin yaratıcı dıĢında birisine böylesi bir duygu besleyebileceğini yine de unutmamak gerekir. Ġkinci beyitte leb, saç gibi unsurlar yaratıcı dıĢındaki varlıklara aittir. ġairin leb, saç gibi unsurlarla yaratıcıyla nasıl bir ilgi kurduğu açık değildir. yine aynı beyitte âb-ı hayatın ilâhî aĢkla ilgisinin ne olduğu belli değildir. ġairin ölme fiilini istemesi karĢısında ölümsüzlük suyunun olduğuna inanması tam anlaĢılır değildir. Üçüncü beyitte Ģairin düĢünde neyi, nasıl gördüğüne değinilmemiĢtir. yaratıcıyı düĢte görmek mümkün müdür? böyle bir rüyayı kim görmüĢtür? kaç kiĢi görmüĢtür? bu soruları cevaplamak zor gibidir. diğer taraftan yaratıcının rüyada görülmesi gibi önemli bir atabey kılıç, age, s. – . resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer olayın üçüncü beyte bırakılması Ģair açısından anlaĢılmayacak bir durumdur. yaratıcının insanla beraber olması gibi güzel bir Ģeyin öncelikli anlatılması gerekmez mi? yoksa Ģair kimi gördüğünden emin değil mi? rüyasını tabir etmek istemesi bundan mı kaynaklanmaktadır? “ben seni benimile görüridim” ne demektir? rüyası sonunda Ģairin hangi duygu ve düĢünceleri yaĢadığı belli değil. hem böylesi bir rüya yorumlanmak istenmez mi? ġair niçin sürece bırakmıĢtır? akla gelen bir soru da Ģu: neden Ģair, rüyasını kendi yorumlamak istiyor? bu neyin göstergesidir? dördüncü beyitte seslenilenin yaratıcı olduğu daha belirgin gibidir. bezm-i ezel terminolojik olarak ruhlar âlemiyle ilgilidir. ruhlar âlemi denilince kuran-ı kerim’de araf süresinin . ayeti akla gelmektedir. ġairin bu ayette anlatılanlara telmih yaptığı anlaĢılmaktadır ama yine yaratıcıya seslenildiği ile ilgili kesin bir bilgi yok. ġair sevdiği kiĢiyi ne kadar sevdiğini hem miktar hem zaman olarak belirtmek için bezm-i ezel kullanımı seçmiĢ olamaz mı? sevdiğine “ben seni ezelden beri seviyorum.” demiĢ olamaz mı? “ben seni severim ezel ezeli/ bana cefa etme dünya güzeli (karacaoğlan)” ifadesi gibi bir kullanımı tercih etmiĢ olamaz mı? birisini çok sevmek anlamında kullanılan “sonsuza dek sevmek” ifadesi “ezelden beri sevmek” ifadesinden farklı bir anlamda mıdır? Ġki ifadenin de anlamı, vurgusu aynı değil mi? ruhların sonsuza dek var olup birbirlerini sevme durumu söz konusuyken, birbirlerini ezelden beri sevme durumu neden söz konusu olmasın? kadı burhaneddin’in dindar kiĢiliği göz önünde tutulursa ezelden ebede ancak yaratıcının sevilebileceği, sevilmesi gerektiği, zorunluluğu, inancı akılda yer etmesi gereken düĢüncedir. kaldı ki mümin olan herkes için bu durum tartıĢılmaz gerektir. ancak yaratıcı çok sevilir, ezelden ebede kadar sevilir. ama bu durum insan olan biri için baĢkaları çok sevildiği zaman sevilen kiĢiye ezelden ebede kadar onun sevileceği ifadesini kullanmayı engeller mi? İki okuma sonrası İlk durum: tam anlama yukarıdaki iki okuma sonrası süjenin dünyasında olan Ģey Ģiirin tam anlamının açık olarak anlaĢılamıyacağı kanaatine varmak olmuĢtur. Ġki okumadan sonra edebî bir eserden neyin nasıl anlaĢılacağı meselesinin kolay halledilebilir bir mesele olmadığı bir kez daha düĢünülmüĢtür. burada bu durumun çalıĢma yapan kiĢiden kaynaklanmadığını önemle belirtmek gerekir. diğer yandan Ģiirin http://www.mcuma.com/ekitap/ / .php bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer Ģerhini yapan süje de böylesi bir güçlüğün olduğunu yazısının sonunda belirtir. sanat eserinin her Ģeyden önce bireye ait olması, eserin tamamen anlaĢılmasını, hissedilmesini engellemektedir. sanatçının birebir yaĢadığı Ģeyin sanatçı dıĢındaki süjelerde tamamen yaĢanmadığı/yaĢanamayacağı bir gerçektir. böylesi bir gerçeklik varken edebî eserin niçin, nasıl ele alınacağını tamamen belirlemek zordur. okumalar ve hayal gücü bir önceki adımda bahsedilen tam anlamanın olmaması durumunda anlaĢılan Ģeyler hayal gücünün ürünü mü? Özellikle yukarıda bahsedilen ilk okumada süjenin yaĢadığı Ģey nedir? hayal gücünün göstergesi ise bunun oluĢmasına neden olan Ģey nedir? veya hayal gücünün okumalarda yeri olmalı mı, olmamalı mı? bunun kontrolü nasıl olacak? dahası böyle bir kontrol olmak zorunda mı? en önemlisi bu hayal gücü kimin? ġairin mi, eseri okuyanların mı? yoksa bu yaĢananlar tamamen farklı bir Ģey mi? hepsinin hayal gücünün kesiĢmesi midir, ayrıĢması mıdır? en önemlisi metnin ilk okunması ve sonrası okumada süjede asıl olup biten, bu olup bitenin de niteliği ve niceliği nedir? metnin İlk okunma zamanı, süjenin İlk okuma zamanı süjenin zihninde canlanan bu düĢünceler süjeyle mi alakalı? bu durumda metnin ilk okunma zamanında yaĢanılanların hükmü nedir? hele metni ilk okuyan süjenin/süjelerin yaĢadıklarının bir hük mü, bir önceliği var mıdır? metinle ilk karĢılaĢan süjeleri böyle bir durumda nereye koyacağız? edebî eserin ortaya çıktığı zaman ile bu eserin sonraki zamanlarda ilk okunması aynı anlamda mıdır? …üstü okuma görülüyor ki bir edebî eser karĢısında bütün bir tavrın nasıl olacağı konusunda bir netlik oluĢturulamıyor. edebî eser karĢısında süje her zaman ayrı bir özele bürünebiliyor. edebî eseri süje istediği gibi ele alabiliyor. edebî eseri okuyan süjenin metin karĢısına kendisini istediği gibi koyması kabul edilecek doğru tutumdur. bu noktada edebî bir eseri okumanın zaman üstü, mekân üstü, sanatçı üstü her türlü Ģeyin üstü özelliklerde olduğu kendiliğinden ortaya çıkmaz mı? okuma ve atabey kılıç, age, s. . resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer anlama noktasında süjenin aĢkın bir konumda olduğu anlaĢılmaz mı? …üstü okumayı ancak süjenin yapacağı gerçeği belirmez mi? sonuç veya sürecin devamlılığı edebî bir eserle ilk karĢılaĢan süje bundan sonra iç içe girmiĢ eylemlerle bu okumayı devam ettirebilir veya bırakabilir. bu anlamda dıĢtan veya süjenin kendi içerisinden okuma ve anlama noktasında birçok uyarıcı gelebilir, gelmeyebilir de. bu noktada dıĢtan gelebilecek uyarıcılara zemin oluĢturmak, önceden baĢlayan genel sürecin devamlığı içine diğer süjelerin dahil olup olmayacağını görebilmek açısından yazının geldiği aĢama sonuç aĢamasıdır. diğer yandan süreç zaten süjede devam edecektir. süjede devam eden sürece dair bir gazel karşısında süje adlı yazının ele alınması metnin giriĢ bölümünde edebiyatla ilgili bir metinle ilk karĢılaĢma anında, sonrasında süjede neler olup bittiğinin sorgulanmak istediği görülmektedir. oysa herhangi bir sanat eseri karĢısında süjede ne olup bittiğinin sorgulanması yapılarak yazıya baĢlanabilirdi. bununla ilgili olarak mesele, sanat eserinin türünün ne olduğuna değil herhangi bir sanat eseriyle ilk karĢılaĢmayla olup bitenle veya devam edenle alakalı olduğuna getirilebilirdi. zira sanat eserinin türünden ziyade onunla ilk karĢılaĢma bütün sürecin Ģekillenmesine etki eden en temel unsurdur. karĢılaĢma olmasa hiçbir Ģekilde süreç baĢlayamayacaktır. ÇalıĢmanın amacında belirtilen sürecin yöntem olarak kullanılıp kullanılmayacağı ifadesinden pratikte böyle bir Ģeyin olmadığının kabul edildiği anlaĢılmamalı. yapılmak istenenin sanat eserini değerlendirmede sürecin etkisinin daha çok vurgulanmasına dikkat çekmek olduğudur. metinle ilk karĢılaĢma öncesi zihnî durumda belirtilen hayatın her bir süje için kendince özel anlam ifade ettiği düĢüncesinin herkeste oluĢtuğunu veya oluĢmuĢ olduğunu kabul etmek sorgulanabilir bir tutumdur. acaba her süje gerçekten hayatın anlamı noktasında kendisine özel bir yer ayırıyor mu? kaç süje böyle düĢünüyor? böyle düĢünmeyen süje acaba var mı? onlar kendi varlıklarını nasıl görüyor ve anlamlandırıyor? metinle ilk karĢılaĢmada süjede sürecin baĢlaması için bir hazır bulunuĢluk olmadan okumaya baĢlamak gerektiği ifadesi anlam karıĢıklığına yol açabilir. zira bir metin var olsun olmasın süjenin her zaman zihnî bir hazır bulunuĢluğu vardır. bu hazır bulunuĢluk olmasa zaten hiçbir Ģey algılanmaz. hazır bulunuĢluk yerine sanat eseriyle bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer önceden karĢılaĢmıĢ süjelerin zihnî faaliyetlerinden habersiz bir zihin ifadesini kullanmak daha doğru olurdu. metni ilk okuma ve Ģerhten hareketle okuma baĢlığı altında verilen düĢüncelerin çağrıĢım hükmünde olması nedeniyle bunların niçin olduğu ve nasıl olduğu noktasında kritik yapmanın anlamlı olmadığını burada söylemek gerekir. zira bu bölümlerde zihnin akıĢı, daha doğrusu süjede olup biten aynen olduğu gibi yazılarak kaydedilmek istenmiĢtir. “Ġki okuma sonrası Ġlk durum: tam anlama, okumalar ve hayal gücü, metnin Ġlk okuma zamanı, süjenin Ġlk okuma zamanı ” gibi baĢlıklarda önceki bölümlerde olduğu gibi süjenin sanat eseri karĢısında özel bir yerinin olduğu düĢüncesinin izleri vardır. sonuçtan önceki bölümde -…üstü okumada- de genel bir süje tavrının ne olduğu düĢüncesinin inanca dönüĢtüğü görülmektedir. acaba bu durum sanat eseri olarak özel olarak kabul edilenin karĢısına ancak özel bir algının yakıĢacağı gerçeği Ģeklinde de ifade edilebilir mi? sonuç/süreç süjede olup bitenin tam anlamıyla ne olduğu halen merak edilmektedir. bir sanat eseri karĢısında süjenin kendi dünyasında yaĢadıklarının ötesinde herhangi bir Ģeyin konulup konulamıyacağı ise asıl merak edilendir. tabii …üstü okumanın nasıl olduğu/olacağı da. zorunlu sonuç/süreç sanat eserinin oluĢturulmasında güzellik temel anlayıĢ olduğu gibi bu eser karĢısında alınacak tavrın genel özelliğinin de güzel olduğu tartıĢılmazdır. bu anlamda sanat faaliyetinin her türlü aĢamasında güzelliğin izleri olduğunu kabul etmek kendinden zorunluluktur. bu zorunluluğun ne demek olduğu daha doğrusu nasıl olduğu ilerde görülecektir. ÇalıĢmamızın amacı olan sürecin iĢlevselliğinin güzele zorunlu olarak nasıl bağlandığı ayrıca kendiliğinden ortaya çıkacaktır. süreçle ilgili düğümlenmelerin güzelle nasıl çözüldüğü anlaĢılacak, sanatın özünün güzel olduğu bir kez daha ortaya çıkacaktır. bu çalıĢmanın zorunlu sonuç/süreç baĢlığının önceki bölümleri yaklaĢık yedi ay öncesinde yazılmıĢtı. o zamanda çalıĢmanın geldiği nokta bir düğüm noktasıydı. genel bir sürecin nasıl iĢleyebileceğini görmek açısından en baĢta düĢünülen çalıĢmayı geniĢ bir okuyucu kitlesine sunmak istenilmiĢ, bu imkân bulunamamıĢtı. diğer yandan süjenin kendisinde süreç zaten devam etti. yedi ay sonrasında klasik Ģiirimizde aĢk konusunu inceleyen bir derginin yayımlanacağı haberi üzerine çalıĢmaya tekrar dönülmüĢ, resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer farklı bir sürece yönelmiĢti. bu süreçte çalıĢmayı aĢkla ilgilendirmek isteyen süje Ģiir karĢısında ilk karĢılaĢmasında estetik tavırdan ziyade daha çok bilgisel tavır takınmıĢ olduğunu fark etmesi üzerine bu isteğinden vazgeçmiĢ bu noktada da farklı bir düğüm yaĢamıĢtır. hem çalıĢmayı bilinçli olarak bu yöne sürüklemek çıkarcı tavır olarak değerlendirilebilirdi. ÇalıĢma faydacı bir noktaya kayabilirdi. süje her Ģey doğal sürecinde seyretsin arzusundaydı. sonrasında Ģiiri estetik bir tavırla seyredip süreci estetik anlayıĢla devam ettirmek istemiĢ, çalıĢmasını bu noktada ele almaya koyulmuĢtur. tamamen estetik bir tavır takınmadan sanat eseriyle ilgili bir çalıĢmanın ne kadar iyi olursa olsun eksik kalacağı inancını duymaya baĢlamıĢtır. gelinen nokta estetik bir tavır almak gerekliliğiydi. daha önce Ģiir daha çok bilgisel, kısmen estetik bir tavırla ele alındığından yeniden bu sanat eseri için tamamen estetik bir tavır almak zordu. en zoru estetik bir tavır olması için estetik tavır alınamıyordu/alınamazdı. zira estetik tavır kendiliğinden olan bir Ģeydir. ÇalıĢmanın bu noktada da geldiği yer düğümdü ta ki güzel kelimesinin kendisinin hissedilip bütün düğümleri açmayı baĢlamasına kadar. artık çalıĢmanın hareket noktası güzelin kendisiydi. alınacak bütün tavırlarda güzel her yönüyle hareket ettiriciydi. estetik tavır veya güzel tavır “Ġnsanın, belli bir estetik değere sahip nesne ya da sanat eserlerine, sanatın bizatihi kendisine, onun aslî değer ve algısal niteliklerine kıymet takdir edecek ve sonuçta estetik bir yaĢantı içinde olacak Ģekilde yaklaĢma imkanı veren, çıkardan bağımsız, anlam ve temaĢa zevki arayıĢıyla belirlenen duruĢ ya da zihin hâli” ,“ereği kendinde bulunan, kendi dıĢında baĢka ereği olmayan tavır ”, “pratik tavrın zıddı” olarak tanımlanan estetik tavır sanat eseri karĢısında alınan diğer tavırlardan farklıdır. yukarıda konu edindiğimiz Ģiire salt bir estetik haz almak için yönelebileceğimiz gibi Ģiirin kadı burhaneddin’in kendi yaĢantısıyla ilgisine veya âĢığın aĢkını nasıl yaĢadığı noktasına da yönelebiliriz. bahsedilen bu tavırlardan ikincisi “bilgisel-düĢünsel” , üçüncüsü “pratik-ahlâksal” tavırdır. ahmet cevizci, paradigma felsefe terimler sözlüğü, paradigma yayınları, Ġstanbul, , s. . Ġsmail tunalı, estetik, Ġstanbul, , s. . ahmet arslan, felsefeye giriş, vadi yayınları, ankara, , s. . Ġsmail tunalı, age., s. . Ġsmail tunalı, age., s. . bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bu açıklamalara göre çalıĢmada süjenin takındığı tavır daha çok bilgisel-düĢünsel tavır olarak gözükmektedir. ne var ki burada bu tavırların birbirinden eserle karĢılaĢma noktasında ne kadar ayrıĢtığı noktasında belirli bir ölçüt olup olmadığını sorgulamak gerekir. dahası bu tavırlar arasında bir dönüĢümün olup olamıyacağı da belirlenmemiĢtir. bilgisel tavırla esere yönelen biri estetik haz alamaz mı? yine pratik noktalardan ele alınan eserden haz olarak bir Ģeyler duyulamaz mı? ana konumuza tekrar dönecek olursak çalıĢmamızı düğüm noktasına götüren estetik tavır alamamanın eksikliğinden yukarıda bahsetmiĢtik. bu düğümü açan Ģeyin güzellik olduğunu da değinmiĢ ama bunun nasıl olduğundan bahsetmemiĢtik. tıkanıklık noktasında güzel kelimesinin iç dünyamızda hissedilmesi üzerine metnin bu kelime açısından ele alınması kendiliğinden oluverdi. bütün bir varlığın güzel olduğu, varlığa bu noktadan bakmak gerektiği zihin ve ruh dünyamızda oluĢuverdi. Ġllaki böylesi oluĢumlar daha önceden kendi dünyamızda, diğer süjelerin dünyasında olmuĢtur. varlık noktasında çoğu kiĢi böyle Ģeyler hissetmiĢtir. sanat eserleri karĢısında da bu hissediĢler olmuĢtur. burada bahsedilen sanat eseri karĢısında da böylesi bir his vardır. güzelin kendisini düĢünüp hissetmek kapıları açıverdi. Ġçimizin güzellik anlayıĢıyla kaplanması sonucu Ģiirle iç dünyamızda hemen bir bağ kuruluverdi. bu duygu ile gerçek sanat eserinin amacının güzeli aramak olduğu düĢüncesi zihinde bir kez daha beliriverdi. bu belirmeyi bütün insanlık tarihinin güzele, mutluluğa, iyiye, doğruya ulaĢmak gayretinden baĢka bir Ģey olmadığı düĢüncesi takip etti. Ġnsanlık tarihi güzele, güzelin özüne ulaĢmak gayretinden baĢka zaten neydi? oluĢ kuramıyla baĢta platon, aristoteles olmak üzere hegel, nietzsche gibi büyük filozofları etkileyen herakletius evrende zıtların bir araya gelmesinden harmony/uyum oluĢtuğunu, bu uyumun da doğal olarak sanattaki uyumu meydana getirdiğini düĢünmüĢtü. aynı harmony düĢüncesini empedokles de taĢımıĢ, diğer yandan pythagorasçılar evrende sayılara dayalı bir uyumun olduğunu düĢünmüĢtü. güzellikle iyiliğin aynı olduğunu xenophon ve platon söylemiĢ , dahası platon sonraki yaĢamında elea okulu özellikle de pythagorasçılardan etkilenerek güzelliği formel-geometrik formlarda ahmet arslan, İlkçağ felsefe tarihi sokrates Öncesi yunan felsefesi, Ġstanbul bilgi Üniversitesi yayınları, Ġstanbul, , s. – . Ġsmail tunalı, grek estetik’i, remzi kitabevi, Ġstanbul, , s. . Ġsmail tunalı, age, s. . Ġsmail tunalı, estetik, s. . resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer aramıĢ, güzel olan salt geometrik-formlardır diyerek önceki güzellik anlayıĢını değiĢtirmiĢ , ama ahmet arslan’ın whitehead’den naklettiği “bütün felsefe tarihi platon’a düĢülmüĢ dip notlarından ibarettir.” cümlesiyle nitelenen bu filozof güzelin öneminden, güzelin kendisinden, kendinde güzelden vazgeçmemiĢtir. platon’un öğrencisi aristoteles de güzeli, bir orantı, matematik olarak belirlenebilen bir kavram olarak ele almıĢtı. “bundan baĢka, “güzel” ister bir canlı varlık, isterse belli parçalardan oluĢmuĢ bir nesne olsun, sadece içine aldığı parçaların uygun düzenini göstermez. aynı zamanda onun geliĢi güzel olmayan bir büyüklüğü de vardır. Çünkü güzel, düzene ve büyüklüğe dayanır. bundan ötürü ne çok küçük bir Ģey güzel olabilir, çünkü kavrayıĢımız, algılanamayacak kadar küçük olanın sınırlarında dağılır, ne de çok büyük bir Ģey güzel olabilir. zira o, bir kez de kavranamaz; bakanda birlik ve bütünlüğü sağlayamaz.” ifadesiyle güzeli tanımlayan “platon’la birlikte yunan dünyasının yetiĢtirmiĢ ve bütün felsefe tarihinin görmüĢ olduğu en büyük filozofu” aristoteles sonraki devirler açısından önemli bir tespit yapmıĢsa da güzellik unsurunu o da kayda değer görmüĢ, güzeli vazgeçilemez olarak değerlendirmiĢti. sonraki zamanlarda da güzellik teorileri oluĢturulmuĢtur. shatfesbury, kant, schiller, schelling, hegel gibi baĢta bu kiĢiler olmak üzere bu alanda önemli kuramlar geliĢtirilmiĢtir. platondan beri oluĢturulan bu güzellik teorilerinin çoğu metafizik karakterdedir. bu teoriler güzelliği mutlak, soyut anlamında düĢünürler. ancak zamanla güzelliğin böyle soyut bir ideye bağlanmadan, sanat yapıtının somut varlığına dayanarak güzelliği temellendirmek gerektiği teorisi-aynı zamanda yöntemi- anlayıĢı hâkim olur. nicolai hartman’ın ontolojiden faydalanarak oluĢturduğu bu teoride/yöntemde sanat ontolojisi teorisi/yöntemi denilen sanat yapıtını, somut varlığa dayandırmak, bunu yaparken de idealiteyi göz ardı etmemek, ikisi arasında(somut varlık-idealite) heterojen bir yapının, ilginin olduğunu kabul etmek gerektiği anlayıĢına hâkim olan Ġsmail tunalı, grek estetik’i, s. – . ahmet arslan, İlkçağ felsefe tarihi sofistlerden platon’a, Ġstanbul bilgi Üniversitesi yayınları, Ġstanbul, , s. . Ġsmail tunalı, grek estetik’i, s. . aristoteles, poetika (çeviren: Ġsmail tunalı), remzi kitabevi, Ġstanbul, , s. – . ahmet arslan, İlkçağ felsefe tarihi aristoteles, Ġstanbul bilgi Üniversitesi yayınları, Ġstanbul, . s. xiv. Ġsmail tunalı, grek estetik’i, s. - . Ġsmail tunalı, estetik, s. vd. Ġsmail tunalı, age, s. . bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer yeni bir ontoloji-sanat ontolojisi- alanı oluĢmuĢtur. bu ontolojinin amacı “sanata ya da sanatçıya ilkeler, yöntemler dikte etmek ya da bir sanat eleĢtiricisi olmak değildir; sanat adını alan varlık- alanını anlamaktır; bu varlık-alanının, insanın varlık-yapısında, varlık- bütünündeki yerini göstermektir.” sanat eserinde güzel unsurunun nasıl belirleneceğini gösteren bu anlayıĢın temelinde, güzellik ne yalnız realiteye ne de yalnız idealiteye aittir anlayıĢı vardır. “güzel, güzel olarak ne yalnız arka plandadır, ne de yalnız ön plandadır, tersine yalnız ikisinde birden bulunur.” güzele aşk, metinle asıl karşılaşma görüldüğü gibi meselenin özü eski çağlardan günümüze kadar aynı. her Ģey güzellikte baĢlıyor, yine güzellikte devam ediyor. sonrasında da güzellikte devam edecek. hartman güzelin nasıl ele alınacağı noktasında tespitleri önemlidir. ama asıl önemli olan bu birlikli yapıyı yine süjenin fark etmesi değil midir? süje varlığa bu nazarla bakmadığı sürece onu tam anlamıyla nasıl görecektir? süje güzel düĢünüp varlığa bu nazarla bakmadığı sürece bu birlikli güzeli görebilir mi? burada asıl önemli olan süjenin güzel düĢünmesiyle sanat eserinin varlığının anlaĢılmasıdır. süjenin güzel düĢünmesi varlığın hepsine güzel nazarla bakmasını getiriyor. varlığın her parçasını ayrı ayrı temaĢa ettiriyor. Çoklukta birlik olduğunu seyrettiriyor. yüce’nin ayrı ayrı tecellileri olduğunu yaĢatıyor, bundan zevk-estetik zevki aĢan- duyuruyor. ÇalıĢmaya konu edinilen Ģiire bu yönde bakıldığında Ģiirin kapılarının kendisini açtığını görülmüĢtür. görülmüĢtür ki Ģiir güzelden/yüceden izler taĢıyor. güzele aĢkı anlatıyor, bunu yaparken de yine yücenin güzel tecellilerinden hareket ediyor. ulaĢılmak istenen Ģey güzel, ulaĢılacak yol da güzel, bu yoldaki her unsur da güzel. ġiirle bu ikinci karĢılaĢmanın süje tarafından asıl olarak nitelendirilmesi bu noktada daha anlamlı görünmüĢtür. zira süje ilk karĢılaĢmayı eksik olarak değerlendirmiĢtir. güzel okuma metinle bahsedilen bu asıl karĢılaĢmanın sonrasında doğal olarak Ģiirin okunması da ilk okumadan farklı bir boyutta seyretmiĢtir. bu okumanın asıl özelliği güzel okumadır. güzel okumadan kasıt Ġsmail tunalı, sanat ontolojisi, Ġnkılâp kitabevi, Ġstanbul, . takiyettin mengüĢoğlu, felsefeye giriş, remzi kitabevi, Ġstanbul, , s. . Ġsmail tunalı, estetik, s. . resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer öncesinde söylediğimiz gibi Ģiire güzelliklerin tecelli ettiği bir unsur olarak bakma tavrıdır. bu tavırla bakıldığı zaman Ģairin yaratıcının güzelliğini, kendi Ģahsından varlığa bakarak yaĢadığı anlaĢılıyor. diğer yandan Ģairin bu tavrı okuyucu süje tarafından güzeli aramada güzel bir tavır olarak değerlendiriliyor. Ġlk okumada seslenilen kiĢinin kim, ne olduğu noktasında belirsizlik olduğu anlaĢılmıĢtı. bu okumada seslenilen kiĢinin yaratıcı olduğu açıkça beliriyor. kaldı ki yaratıcı dıĢında birine sesleniyor olsa bile bu hitabı yücenin kendi güzelliğinin ayrı bir tecellisi olarak değerlendirmek gerekiyor. Şerhi güzellikle okuma Ġlk okuma sırasında oluĢan anlam belirsizliklerin bir anda güzel okumayla ortadan kalktığı gibi Ģerhten hareketle okumayla akla gelen soruların da ortadan kalktığı süje tarafından anlaĢılmıĢtır. sayın kiliÇ’ın Ģerh/okuma/anlama faaliyetine bilgisel bir tavır alarak değil yine güzeli merkez alan bir yaklaĢımla yöneldiğimizde Ģiirin kiliÇ’ın söylediği gibi yaratıcı aĢkını iĢlediği görülmektedir. güzel okuma sonrası durum: duyulan haz/tam haz ġiirin bu Ģekilde yeniden okunmasıyla süjede mutluluk veren bir haz duyulduğu kesindir. estetikçi bir yaklaĢımla ele alınan edebî bir eserin süjede oluĢturduğu en üst Ģey metni tam anlamadır. kaldı ki metni tam anlama her zaman kolay ulaĢılacak bir nokta olarak görülmüyor. esere estetik bir tavır almanın oluĢturduğu haz kuĢkusuz baĢka bir Ģeyle en azından tam anlamayla mukayese edilemez. diğer yandan kendi dıĢında baĢka ereği olmayan tavır olarak bilinen estetik tavrın güzel düĢünen güzel görür, güzel gören her Ģeyden lezzet alır anlayıĢıyla iliĢkilendirilmesi varlığın herkes tarafından güzel görülebileceği zeminini oluĢturması açısından önemlidir. güzeli sürekli yaşama/hazzın kesilmemesi, aşkınlık varlıkta güzeli sürekli olarak yaĢayabilmek mümkündür. güzellikten edinilen hazzın bu anlamda devamını sağlamak da imkân dâhilindedir. Ġnsanlar kendi benliklerinde bu hazzın devamını sağlayacak dinamikler oluĢturabilirler. ama bu hazzın tam olarak ne olduğu, nasıl yaĢandığı bu çalıĢmanın hacmini aĢmaktadır. güzelle yaĢanılan alakanın tam olarak ne olduğu çalıĢmanın hacmini aĢan ayrı bir konudur. güzelin aĢk, iĢtiyak, alaka ile ilgili boyutlarının, ötelerle ilgisinin süjede nasıl mülahazalar oluĢturduğu çalıĢmayı, benliği aĢan noktalardır. bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer hakem süreci yukarıdaki bir gazel karşısında süje veya …Üstü okuma; sadece güzel baĢlıklı yazının çıkıĢ noktası Ģuydu: “herhangi bir süje(ben) olarak öyle veya böyle karĢılaĢmıĢ olduğum bir edebî eser karĢısında bütün bir benlik dünyamda olup biten nedir?” sorusunun cevabını sorgulamak. bu hareket noktasının temelinde bu sorunun cevabının ne olduğu vardı. bunun yanında bütün bir sürecin benliğimi bu anlamda nasıl yönlendirdiği diğer bir merak unsuru olarak kendiliğinden belirdi. bunu takiben diğer süjelerin bir eser karĢısında kendi dünyalarında neler olduğu merakı, sonrasında da kendi benliğimle diğer süjelerin benlik dünyalarının süreç içerisinde birbirlerini etkileyip etkilemeyeceğini öğrenmek isteği oluĢuverdi. bütün bunların sonucunda bütün süjelerin beraber bir edebî eser karĢısında bir anlam dünyası oluĢturup oluĢturmayacaklarını, sürecin bu anlam dünyasının oluĢmasında bir yöntem olarak kullanılıp kullanılmayacağını görmek isteği çalıĢmamızın konusunu oluĢturuverdi. bu düĢüncenin pratiğe aktarılma sürecinde nelerin yaĢandığı ile ilgili tespitler yazımızın buraya kadar olan bölümünde bulunmaktadır. yazımız yukarıdaki süreçleri geçirdikten sonra hakem sürecine gelmiĢ bulunmaktadır. bir gazel karşısında süje veya …Üstü okuma; sadece güzel baĢlıklı yazımız, düĢüncelerimizi diğer süjelere sunma imkânını bulduğumuz bir dergiye gönderilmiĢ, derginin iki hakemi tarafından ön değerlendirilmeden geçirilmiĢ, bu değerlendirmeler tarafımıza iletilmiĢtir. Öncelikle Ģunu belirtmeliyiz ki hakemlerin çalıĢmamızda konu edinilen Ģiire nasıl tavır takındıklarını göremedik. ġiiri merkeze alan değerlendirme yapacakları beklentisi bu anlamda boĢ çıkmıĢtır. dolayısıyla Ģiirin bu süjelerce nasıl algılandığını/anlamlandırıldığını/yorumlandığını görmek isteği, hakemlerin bu yönde sürece dahil olmalarını beklemek de sonuçsuz kalmıĢtır. sürecin Ģiiri esas alan değerlendirmeler, yaklaĢımlarla devam edeceği umuluyordu. yukarıda geçen kadı burhaneddin’in Ģiirini merkeze alan yoğun bir sürecin yaĢanacağını umut etmiĢtik. beklediğimiz gibi bir süreç olmasa da yine de süreç devam etmektedir. hakem değerlendirmelerinin dikkate alındığı bir süreç içerisine girilmiĢtir. görüleceği üzere yazımız baĢlayıp devam eden bir süreci içerdiği için yazının önceki bölümlerine herhangi bir ekleme yapılması çalıĢmanın formatını bozacaktır. bu noktada yazımızla ilgili değerlendirmeler yapan hakemlerin düzeltme önerisi bulunduğu yerleri hem yazının bütünlüğünü bozmamak hem de sürecin nasıl devam ettiğini göstermek açısından değiĢtirmeyecek, bu önerilerle resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer ilgili düĢüncelerimizi, tartıĢmalarımızı buradan devam etmek suretiyle belirtip, düzeltmelere bu Ģekilde değineceğiz.  bir gazel karşısında süje veya …Üstü okuma; sadece güzel baĢlıklı yazımızı ortaya koyarken edebî bir eser karĢısında tavrın ne olduğu konusunun tartıĢmalı bir konu olduğu düĢüncesinden baĢlamıĢtık. “tartıĢmanın merkezinde edebî eserin ne olduğu, bu eser karĢısında süjenin özellikleri ve bunların süreçle olan ilgisinin hangi boyutta olduğu konuları vardır.” düĢüncesini belirtmiĢtik. yazımızı hakemlerin birbirlerinden farklı olarak değerlendirdiklerini görmemiz edebî eserin süjelerce farklı algılanabileceğini doğrular niteliktedir. zira bir düĢünce eseri farklı olarak algılanıyor, değerlendiriliyorsa hayli hayli bir sanat eseri süjelerce farklı algılanır, anlamlandırılır. hakemlerden birisi makale değerlendirme kıstasları noktasında yazımızı yeterli bulup sadece süje tanımının yapılmamasını eksiklik olarak değerlendirmiĢtir. yapılacak süje tanımının yazıyı daha akıcı hâle getirebileceğini vurgulamıĢ ki bu düĢüncesinde haklıdır. yazımızda sıkça geçen süje türkçe sözlükte konu, özne olmak üzere iki anlamda verilmiĢtir. bizim yazımızda “özne” anlamında kullanılmıĢtır. gerek baĢlıkta gerek yazının genelinde “özne” kelimesini kullanmayı düĢünmüĢsek de Ġsmail tunalı’nın kitabında süje kelimesi kullanıldığı için felsefî anlamda genel kullanıma uygun olması açısından bu kelimeyi kullanmayı tercih ettik. diğer taraftan hâlen özne kelimesinin kullanılabileceği zihnimizdedir, dahası yazıda süje kelimesi yerine özne kelimesini koyarak bir değiĢikliğin yapılması baskın gelmektedir. Ġlerleyen süreçte bu değiĢiklik yapılabilir. “genellikle süje bir bilgi öğesi olarak anlaĢılır. Ġnsan bilinç sahibi bir varlık olarak, kendisinin dıĢında bulunan nesneleri kavradığı gibi, kendi varlığını, iç gözlemle de kendi bilincini kavrar. bu kavramaya bilme adı verilir. bilme olayında bu algılayan, kavrayan bilinç varlığına, ben’e süje dendiği gibi, algılanan, kavranan varlığa da obje denir.” Ģeklinde süje’yi tanımlayan tunalı, estetik bir obje karĢısında süjenin bilgi süjesinden çıkarak estetik süjeye dönüĢtüğüne değinerek estetik süje özelliklerinden bahseder. “buna göre estetik süje, bir estetik obje’yi algılayan, onu kavrayan ve ondan estetik olarak hoĢlanan, ondan estetik haz duyan bilinç varlığı ben anlamına  hakemlerin gerekli gördüğü teknik düzeltmeler; imlâ, noktalama vb. yazı üzerinde düzeltilmiĢtir. http://tdkterim.gov.tr/bts/?kategori=verilst&kelime=s%fcje&ayn=tam Ġsmail tunalı, estetik, s. . Ġsmail tunalı, age, s. . bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer gelir.” ifadeleriyle estetik süje’yi açıkladıktan sonra süjenin obje karĢısındaki tavır alması noktasına konuyu getirir. estetik tavır dediği bu tanımlamanın özelliklerine yazımızın önceki bölümlerinde değindiğimizden dolayı burada değinmeyeceğiz. yazımızda çok basit bir anlamda bir Ģiir karĢısında bir süje olarak kendimizde, benliğimizde ne olduğu, sürecin benliğimizi nasıl Ģekillendirdiği, etkilediği noktasında durmak istedik. daha önce değindiğimiz gibi yazımızın çıkıĢ noktasının bu olduğunu söyleyerek diğer hakemin değerlendirmelerine geçmek istiyoruz. diğer hakem ise makale değerlendirme kıstasları noktasında yazımızı çoğu yönden yetersiz bulmuĢtur. Öncelikle konunun karıĢık olarak ele alındığını belirtmiĢ, konu baĢlığının uygun olmadığına karar vermiĢtir. bu tespitlerle ilgili olarak Ģunları söyleyebiliriz: her Ģeyden önce yazının baĢlangıcında bir konunun olduğundan bahsedebiliriz. ancak dikkat edilirse yazının geneli bir konudan ziyade edebî bir eser karĢısında süjenin süreçte neler yaĢamıĢ olduğunu anlatır. baĢlangıçta bir Ģiir karĢısında süjenin tavrının ne olduğu konusu var ise de sonrasında sürecin nasıl devam ettiği olduğu gibi kaydedilmiĢtir. konu baĢlığı ve alt baĢlıklara da bu zaviyeden bakılması gerekir. konu baĢlığı süjenin yaĢadığı bütün bir süreci özetler niteliktedir. bu noktada konunun baĢtan ele alınması söz konusu olamaz. zira baĢtan ele almak bütün bir süreç göstergelerini ortadan kaldırmak olacaktır ki biz de böyle bir Ģey olsun istemiyoruz. bundan sonrası için meseleyi sistemli bir Ģekilde ele almak gerçekleĢebilir veya gerçekleĢmeyebilir. daha önce söylenildiği gibi sürecin nasıl devam edeceği bilinmemektedir. aynı hakem estetikle ilgili kaynakların görülmediği hükmüne varmıĢ ki öncelikle alanında önemli kaynakların okunmuĢ olduğunu, bunların da kaynakçada belirtildiğini burada vurgulamak gerekir. Ġkinci olarak estetik alanıyla ilgili daha çok kaynağın olduğu gerçektir. ama yazının amacı teorik olarak bir düĢünce eseri yazmak değil bir sanat eseri karĢısında bütün olarak nelerin olup bittiği- seyretmek/anlamak/sezmek/kavramak- sürecini yaĢamak isteğidir. yine aynı hakemin Ģiirin Ģerhini anlamak için çeĢitli Ģerh kitaplarını tavsiye etmesi kabul edilebilecek bir tutumdur. yalnız gönül isterdi ki hakem bu Ģiir hakkında kendi sürecinde ne olduğunu yazmıĢ olsun. bu durumda Ģunu önemle belirtmek isteriz ki hakem bu Ģiir karĢısında bir tavır almamıĢ olabilir, buna da diyecek bir Ģey olamaz. Ġsmail tunalı, age, s. . resul kaya turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer hakemin yazıyı dilbilimsel, felsefî, estetik açılarından birinin seçilerek yeniden ele alınması noktasındaki tavsiyesi üzerine diyebileceğimiz Ģu ki yukarıda bahsedilen alanlar birbirlerinden tamamen ayrı alanlar değil. dolayısıyla yazıyı bu alanlardan biri üzerine yoğunlaĢtırmak zorlama bir iĢ olur. kaldı ki yazımızı herhangi bir minvalde devam ettirme gibi bir kaygımız olmamıĢtır. bundan sonraki süreçte de ne olur bilemeyiz. daha önce iki hakemin de birbirlerinden farklı olarak yazımızı değerlendirdiğini belirtmiĢtik. bu farklılığın algı farklılığından kaynaklandığını da ifade etmiĢ, düĢünce eserleri karĢısında bile farklı algılar olabiliyorsa edebi eserlerin farklı algılanmasının hayli normal olduğu, dolayısıyla bu anlamda yazımızın çıkıĢ noktasının önemli bir temele dayandırılmıĢ olduğu hükmüne varmıĢtık. yukarıda iki hakemin yazımızı birbirlerinden farklı noktalarda değerlendirdiğini göstermiĢ olmamız bu durumu daha da açıklar niteliktedir. yazımıza bu Ģekilde bir hakem süreci eklenilmesi önceden düĢünülmüĢtü. herhangi bir yönlendirme olmasın diye dergi editörüne böyle bir çalıĢma süreci içerisinde bulunulacağı söylenmemiĢtir. amacımız her yönüyle doğal bir süreci yaĢamaktı. hakemlerin de böylesi bir çalıĢmadan haberdar olmadığını düĢünüyoruz. yazımızın formatından hareketle böyle bir sürecin yaĢanabileceği tahmininin yapılabileceğini düĢünmüĢtük. dergi yönetimine, hakemlere bilmeden bir kusur ettiysek Ģimdiden özür dileriz. amacımızın bir edebî eserin yaĢantımıza nasıl dâhil olduğu, olabileceği sorgusunu süreç içerisinde yapmak olduğunu tekrar önemle ifade etmek isteriz. kaynakÇa aristoteles, poetika (çeviren: Ġsmail tunalı), remzi kitabevi, Ġstanbul, . arslan, ahmet, felsefeye giriş, vadi yayınları, ankara, . arslan, ahmet, İlkçağ felsefe tarihi sokrates Öncesi yunan felsefesi, Ġstanbul bilgi Üniversitesi yayınları, Ġstanbul, . arslan, ahmet, İlkçağ felsefe tarihi sofistlerden platon’a, Ġstanbul bilgi Üniversitesi yayınları, Ġstanbul, . arslan, ahmet, İlkçağ felsefe tarihi aristoteles, Ġstanbul bilgi Üniversitesi yayınları, Ġstanbul, . bir gazel karşısında süje veya… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer cevĠzcĠ, ahmet, paradigma felsefe terimler sözlüğü, paradigma yayınları, Ġstanbul, . kiliÇ, atabey, “kadı burhaneddin’in bir gazelinden hareketle”, klâsik türk edebiyatı Üzerine makaleler, turkish studies publication, ankara, , s. – . mengÜġoĞlu, takiyettin, felsefeye giriş, remzi kitabevi, Ġstanbul, . tunali, Ġsmail, estetik, Ġstanbul, . tunali, Ġsmail, grek estetik’i, remzi kitabevi, Ġstanbul, . tunali, Ġsmail, sanat ontolojisi, Ġnkılâp kitabevi, Ġstanbul, . http://www.mcuma.com/ekitap/ / .php http://tdkterim.gov.tr/bts/?kategori=verilst&kelime=s%fcje&ayn=ta m http://www.mcuma.com/ekitap/ / .php wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ the marketing review , , - www.themarketingreview.com issn - / / / + £ . / ©westburn publishers ltd. wolfgang messner softlab gmbh, frankfurt the beauty and importance of quality customer information many executives find the subject of data management to be unglamorous and mind-numbing. they pay only lip service to their company’s need for quality customer information – until they realize how much is really at stake. when a critical project cannot go live due to data quality problems, the response rate on marketing campaigns is substandard due to an inability to define proper target groups or the total credit outstanding of international customers cannot even be estimated – only then senior management begins to take notice. poor customer information means not only wasted money, but also key performance indicators and thus the basis for guiding the corporate strategy might be flawed. after the eu has included data privacy into the charter of human rights and member states have adopted the eu data privacy directive into national law, the legitimacy and correctness of storing and processing customer information is at stake. this paper focuses on the banking industry; its key considerations and concepts can equally be applied to other industries where companies are storing and handling detailed data on a large number of customers. introduction according to research why projects in the area of customer relationship management (crm) fail, one key reason is that the customer data is being ignored (nelson and kirby , p. ). “although a crm initiative may have multiple vendors and timelines that take months or years to implement, the vast majority of enterprises pay no attention to the data that will support investments and systems” (nelson and kirby , p. ). senior managers need to understand the need, importance and legal implications of a good foundation of data and professional customer data management if they are to get best value from customer data: “good customer management requires good customer data management” (foss et al. , p. ). then enterprises will find that subsequent investments in crm projects will correspondence: wolfgang messner, business segment crm, softlab gmbh, hanauer landstrasse , frankfurt am main, germany, email: wolfgang.messner@softlab.de / wolfgang.messner@epost.de similarly, in a study among institutions in germany (link/hildebrand , p. ) difficulties with getting customer information and it-related challenges have been highlighted as the main problems in the area of database marketing (dbm). http://www.themarketingreview.com wolfgang messner generate acceptable payback. in many banks, customer data was originally collected and managed departmentally per branch or by individual account managers. some banks still operate this way. it was not possible, for example, to understand the needs and preferences of the individual customer, judge his value, determine his potential or get a management overview on how the bank is doing business within one customer segment. but it is the advancement in computer technology which helps companies to understand and communicate with customers who have specific characteristics and attributes (christopher et al. , p. ). this paper provides guidance on how banks – as an example for companies handling large volumes of data – can enhance the quality, quantity and meaningfulness of customer information data. the analysis is framed by the following key issues: • creation of a consistent crm data architecture • evolving analytical systems to leverage customer information • discussion of legal implications and data privacy issues creation of a consistent crm data architecture most banks have several – if not hundreds – of different operational sources containing data concerned with their customers. thus for all, but the simplest or most recently founded banks with a clean system architecture, a universal database containing all customer information will remain an elusive desire. therefore most banks will be forced to source customer information from multiple systems and combine them to create a single, integrated view of the customer as the cornerstone for all crm initiatives. different semantics add to the complexity. for example, what is meant by the term customer? is it an individual, the household or a corporate client? frequently these meanings are not consistent from one data source to the next. when multiple departments are capturing data, their priorities and requirements may differ (berrian , p. ). account managers in private wealth management may want a physical address where they can best reach and meet their clients, but accounting may want to have a mailing address. the creation of multiple customer touchpoints also increases the danger of capturing incorrect or duplicate information. a crm project needs to first understand and then to reconcile all these different needs, semantics and their usage within the bank. this is a laborious and arduous task which is often underestimated (kramer , p. ). the next challenge is in accessing all these heterogeneous databases. this requires special know-how about technology which is sometimes up to years old. “after years of piecemeal technology purchases, companies have inevitably ended up with a mishmash of disparate systems spread throughout different units” (hagel and brown , p. ). the major core banking systems have certainly solved some problems, but they have also the beauty and importance of quality customer information created new ones. because they are relatively inflexible, they tend to lock banks into rigid business processes. it becomes difficult to adapt quickly to changes in the marketplace, strategic partnerships and mergers & acquisitions. a more strategic challenge is in designing the future architecture. there is a choice between handing over control to the data model of the new crm system or retaining control of the data model and architecture. in most crm projects enterprises and banks choose to use a vertical specialisation of the data model provided by the crm vendor. this poses two significant challenges. first, a new operational database with its own data model and semantics has to be introduced. second, the new database will have to be populated with data from existing systems. it will have to be integrated via appropriate interfaces, replication or migration depending on the volume of data and the frequency of updates. this could portend to possible synchronisation problems tied up with an implementation of bidirectional and real-time data transfers. today, data trickles slowly through the enterprise, as more than percent of integration is still done with batch file transfers (gartner , chap . ). also, the issue of the leading system has to be discussed. as some of the functionality and data will be duplicated by the crm suite, it has to be decided, which functionality should be pulled out of the established systems and re-used or substituted with functionality from the vendor. in some cases the bank might have to live with duplicate functionality leading to inconsistent business process support. high low low high volume of data to be processed frequency of update interfacing replication migration source: foss et al. , p. figure . data movement – timing and volume the second option is to retain control of the entire crm data architecture and to map the new crm functionality right into the established databases. this approach brings its own challenges and operational risks in terms of wolfgang messner manipulating the heart of the core banking systems. thus a variation would be to introduce a new operational data store (ods). the ods would on one side interface with the new crm system and other superordinate leading applications. on the other side it would connect to the established databases (conrad ; feld and stoddard ; gartner , chap . ; hagel and brown ). providing this integrated view of data does not come without challenges. the autonomy of local applications must not be endangered; it needs to be possible to continue using the existing applications. the integrity, consistency and dependencies of redundant data needs to be ensured. potential access (write, update, delete, read) conflicts need to be handled by a global transaction management agent. - figure . introducing a new operational data store frequently data complexity is also caused by business process complexity (foss et al. , p. ). then process reengineering, simplification and introduction of straight-through processing (stp) should be the focus for the bank. once the process landscape and the architectural framework has been laid, data needs to be treated as a ‘holy grail’. it is a valuable asset for the bank and resources for its maintenance need to be allocated. rather than struggling with defining and assigning ownership of complete subject related data areas, the nature of distributed data should be accepted and data stewards (gartner , chap . ) should be named who are responsible for the quality and consistency of a smaller designated portion of data. it is recommendable to place this responsibility as close to the point of data operational data store (ods) crm system superordinate applications application application dbs dbms db dbs dbms db dbs dbms db dbs dbms db dbs n dbms n db n dbs n dbms n db n ... key: dbms= database management system db = database dbs = database system ods = operational data store the beauty and importance of quality customer information capture as possible. robust measures of data quality and its impact on customer management processes need to be build. these measures should include, for example, financial data on wasted marketing activity generated by poor data inputs, the amount of rework undertaken at information- intensive stages in customer management processes (stone et al., p. ). customer-facing employees should have incentives and sanctions in place relating to customer-information quality in the respective data stewardship area. evolving analytical systems to leverage customer information information technology in banks is generating more and more data and is permitting it to collect or capture various information. technology also makes it possible to use the extended data, conduct comprehensive analysis (porter and millar , p. ) and develop a fine-grained customer understanding on a mass scale. this makes “various crm functions like customer segmentation, communication targeting, retention, and loyalty much more effective” (srivastava et al. , p. ). in order to translate customer data into measurable results, banks need to focus on creating an analytic capability that enables to leverage customer information through data aggregation and analysis to gain customer insight, make better decisions, and shape future customer interactions (harris , p ). banks need to recognize that crm impacts many different aspects of their business. the first steps are to determine what customer specific insight is actually needed to plan and optimize customer relationships and what metrics will subsequently measure the success in meeting the bank’s strategic objectives. by working backward from the business goal, it is possible to concentrate on the source of the appropriate data, rather than collecting and analyzing all kinds of irrelevant data simply because it is readily available in the bank (gartner , chap . ). as so much of the usefulness of customer data depends on how it is analysed, the analytical capabilities should be one of the first areas to plan (foss, et al. , pp. - ). as outlined above, data must be extracted from several databases, transformed into a usable format and integrated for loading into an analytical database. this process is called etl (extraction, transformation and loading). internal data can be enriched with external data to complete possible gaps. however, external data is not considered as valuable as internal data since it is also available to competitors. banks can classify three different fields of data to effectively manage their customer relationships: • identification data focuses on identifying the customer. it contains the name, company or household, address, customer and account number. • the customer status describes the status of the relationship between wolfgang messner the customer and the bank together with the probability of converting a market participant into a customer. the following five levels are possible: non-usage of offered banking products, usage of similar or competing banking products, contacted non-customers, prospects and customers (adapted to the banking industry from link and hildebrand , p. ). • additional customer information about the customer is sometimes also referred to as descriptive data (arndt and gersten , p. ). much of this data comes from the interaction of the bank with the customer, surveys or behavioural studies and is therefore likely to be incomplete or outdated. it is the bank’s responsibility to keep this data up to date and clean as the customer is highly unlikely to inform the bank about changes in this contextual kind of data. • the customer history contains details on the transactions that comprise the relationship between the bank and the customer. • marketing data entails summarized analytical results of information available about the customer, for example the customer value, potential, risk of attrition, channel preference, need analysis, cross- selling opportunities, contact occasions and information about campaigns. • contractual data is about contracts between the bank and the customer including legal data (like the facility id and the agreed limit) but also transactional and product utilization data (like drawings under the umbrella of the facility). there are four main components to customer data quality (foss et al. , pp. - ; stone et al. , p. ): • data completeness is the proportion of all possible relevant data sources and the coverage across all defined fields of data (see above) that a bank has integrated into its business processes. • data accuracy is the overall exactness of the data associated with each customer record. data grouping accuracy refers to how the bank can consolidate and match data from disparate sources. through experience the bank and its employees need to gain confidence in data accuracy to ensure that it is fully utilised and exploited. • data appropriateness measures how close data matches the business purpose for which it is actually collected and processed. static appropriateness describes how well the data represents a customer and his current behaviour. dynamic appropriateness takes it a step further into the future and depicts whether the data tactically (i.e., cross-selling, event generation) or strategically (i.e. decision making in terms of new products, customer segments and the development of value propositions) supports the business direction of the bank. the beauty and importance of quality customer information • data access describes the speed and accuracy with which a bank can integrate its data and provide information in a usable form to customer-facing applications in a multi-channel environment. analytical crm systems provide many different types of analysis supporting different needs within the bank: customer analysis, financial analysis, market analysis and management-metrics. applying customer insight – that is making information actionable – as an outcome of analytical crm aims at optimizing the relationship with the customer by planning and executing customer interactions through: • campaign interactions through outbound marketing campaigns. campaign management systems improve efficiencies by reducing marketing cycle times and by building optimal target groups through applying customer insight. but the real benefit in outbound marketing comes from centralising campaign management across the growing marketing mix of channels, products and customer segments (silva , p. ). • event-driven interactions, in which an event at the customer suggests that the customer may be likely to respond positively to an approach by the bank. these interactions take the form of : campaigns and can be described by the latin term in-speculis (messner , p. ). • inbound marketing leverages customer insight into all inbound contacts of the customer by “wrapping a targeted message around the tactical response provided to the customer” (gartner , chap . ). the bank needs to develop a closed loop system that will feed information to dedicated recipients across the bank and allow them to give feedback based on their activities. this feedback can in turn be used to keep the data up to date and to further refine the analytical studies. most algorithms as implemented in today’s crm tools stop at discovering customer models, at pointing out customers who are likely attritors or who are profitable. while these techniques are essential to put the data mining result into action, they still require human experts to postprocess this information manually and do not directly suggest actions (yang et al. , p. ). to improve customer relationship, the bank must know what measures to apply to make an individual customer more profitable. to date there are no mining algorithms widely available which accomplish this task automatically. one computational possibility is to build up customer profiles in the form of decision trees, which classify customers and provide profit probability of customers. when a customer of the database falls into a particular leaf note, an algorithm tries to move the customer into other leaves with higher profit probability. for conducting this move, some attribute values of the customer need to be changed through actions which incur marketing costs. the collection of moves should maximize the net profit, which equals the gross wolfgang messner profit minus the cost of the corresponding actions (yang et al. , pp. - ). discussion of legal implications and data privacy issues it is this very bringing together of information about the customer into a single database that can potentially be at odds with the law (stone and findlay , p. ). initially, privacy protection in europe was driven by the desire to prevent government use of personal data for purposes of executing malicious policies, as had happened in totalitarian states (bergkamp , p. ). the eu commission started working on data protection legislation in the late ’s, and enacted directive / /ec on the protection of individuals with regard to the processing of personal data and on the free movement of such data on th october . all member states were required to incorporate the eu data protection directive into national law within three years. but by then several eu member states had already adopted privacy legislation and had to amend existing national law (becker et al. , p. ). in the eu had again reinforced its statement on data privacy protection by including it in the eu charter of human rights, which provides that “everyone has the right to the protection of personal data concerning him or her” ( /c / , art - ). hence the eu judges data privacy to be a fundamental core human right – at the same level as, for instance, prohibition of torture or slavery and the freedom of expression. the data protection directive generally prohibits, subject to listed exceptions, the collection and processing of personal data. as a consequence, the bank as a processor of data bears the burden of proving that the processing is lawful (asymmetry of proof). as a result, it has become much easier to prove positively that an activity of the bank results in specific harm to a customer. where data collection is permitted, serious restrictions are imposed on personal data processing. individuals are granted the right to be informed about data processing and, in some instances, their prior consent must be obtained. in marketing jargon, this is also known as opt-in or permission marketing. in addition, there is a right to access data pertaining to the individual, rectify incorrect data and a right to object to data processing. furthermore, confidentiality and security have to be ensured by the bank. the bank is obliged to ensure “that personal data must be […] adequate, relevant and not excessive in relation to the purposes for which they are collected and/or further processed; […] [it also has to be] accurate and, where necessary kept up to date” ( / /ec, art ). relating this directive to the so-called customer soft facts (additional customer information, see above) imposes great legal risks. it is common practice for account managers to try to collate as much information about the customer as possible. while information about preferred investment assets or a risk profile is typically required for conducting an asset management respectively lending business, storing information about hobbies and other preferences would pretty openly contradict the eu directive. also, there is no differentiation if this kind of information is stored electronically in a crm the beauty and importance of quality customer information system or via the old-fashioned way in the account manager’s own folders. such folders would also be governed under art. c of the eu directive, where filing systems are defined as “any structured set of personal data which are accessible according to specific criteria, whether centralized, decentralized or dispersed on a functional or geographical basis” ( / /ec, art b; / /ec, dir ). as a consequence of raising data privacy as a core human right in the eu charter of human rights, the cost of data protection no longer matters because privacy is fundamental and therefore must be protected by all means. the eu privacy legislation does not provide for cases where the cost of privacy is becoming excessive and as it is a fundamental human right, a business case or cost/benefit-analysis would be inappropriate. however, one could argue, that privacy protection is a valuable good which – unlike prohibition of slavery, for example – is in competition with other rights for resources and is therefore subject to the law of diminishing marginal returns (bergkamp , p. ). once banks have addressed the most serious security threats, further investments in privacy protection may provide only little added value while becoming very expensive at the same time. is the customer really willing to pay a significant higher price for this? it could further be argued, that because data privacy is a fundamental human right, it cannot be given up by any individual. it is an inalienable and non-waivable right, just like you are not in a position to surrender yourself to slavery. even if an individual wishes to give up some or all of his privacy rights to obtain a lower price for a product or service, eu law will not let him do so. the eu is trying to portray the privacy issue in terms of a fight of consumers versus enterprises. it does not take into account the nature of conducting business, e.g. an advisory business like private wealth management is fully dependent on customer information. being aimed at protecting the individual against risks arising from data misuse, the eu seeks to ensure a very high level of protection – but it fails to specify the risks involved with using customer information in its data protection directive. in practice, the bank should focus on art. of the eu data protection directive together with art. - of the eu charter of human rights which both provide cases in which enterprises may conduct data processing: • the customer has unambiguously agreed to data processing. this can be achieved by asking him to sign an agreement while account opening. • data processing is necessary for performing the contract. clearly, this enables the bank to maintain an account history, transfer payments and provide consultative advice. internet-only banks priding themselves in customer self-service without any consultative function might experience some restrictions. but in both cases, calculating the value of the customer for the bank is not quite necessary for performing the contract. the current trend and enthusiasm of customers towards bonus programs and different levels of club- wolfgang messner membership depending on the value of business conducted might be a good remedy to lawfully perform such calculations. • data processing is also allowed if there is a need to comply with legal requirements (e.g. calculate tax on interest income) and to protect public, official (e.g. ensure taxation) or other legitimate interests (e.g. discover money laundering). according to a recent study of qci, less than percent of the (mainly european) enterprises claim to have implemented robust programmes to tackle the legislation-affected issues (stone et al. p ). however, the issue is still broader than compliance with legislation – a possible loss of customer confidence is more alarming. the aarp survey shows that even though citizens might not be well informed about their financial privacy rights, they believe it is very important that their personal, financial information is not shared without their permission (bridges , p. ). an overwhelming majority say it is very important ( percent) and fewer than four percent say financial privacy is not important to them. remarkably, the survey did not show any differences by age, income, or education in the importance citizens place on the right to financial privacy. but the survey also shows that only percent of the people questioned have a correct view when financial institutions are required to provide privacy statements to their customers and whether these institutions are required to obtain consumers’ consent before their personal, financial information (bridges , p. ). conclusion one hundred percent accuracy, integrity and lawfulness are rarely achievable. the world of banking is simply too complex. but this should not deter banks and other companies from defining and structuring, what their information needs and data availability are, what transformations are needed and what activities have to follow. it is important to prioritise and focus on getting a close loop through to the customer-facing employees and applications, further to involving the customer and back to the business processes and applications of the enterprise. customers now have a fundamental right to expect corporations to manage their data professionally. this is no longer just a marketing question, as long as the eu continues with their strict understanding of data privacy, companies are advised to find innovative ways – like bonus programs, club memberships or value-added service offerings – to allow them to actually store customer data and turn it into valuable customer information. a randomly selected sample of vermont residents age + was interviewed beginning of . the beauty and importance of quality customer information references becker, j., serries, t., dreiling, a. and ribbert, m. ( ), “datenschutz als rahmen für das customer relationship managmeent – einfluss des geltenden rechts auf die spezifikation von führungsinformationssystemen“, working paper no. , westfälische wilhelm-universität münster, institut für wirtschaftsinformatik, münster. christopher, m., payne, a. and ballantyne, d. ( ), relationship marketing – creating stakeholder value, elsevier butterworth-heinemann bergkamp, l. ( ), “eu data protection policy – the privacy fallacy”, computer law & security report, vol. , no. , pp. - berrian, c. ( ), “turning your data into revenue – a marketing guide”, white paper, d&b sales & marketing solutions bridges, k. ( ), “aarp vermont financial privacy survey”, aarp, washington dc, conrad, s. ( ), föderierte datenbanksysteme – konzepte der datenbankintegration, springer-verlag feld, c., stoddard, d. ( ), “getting it right”, harvard business review, february foss, b., henderson, i., johnson, p., murray, d. and stone, m. ( ), “managing the quality and completeness of customer data”, journal of database marketing, vol. , , pp. - gartner ( ), “building business benefits from crm – how to design strategy, people, processes and architecture to succeed”, gartner group, r - , may hagel, j. and brown, j. ( ), “your next it strategy”, harvard business review, pp. - , october harris, j. ( ), “finding the customer in transaction data”, working paper, accenture institute for strategic change, december kramer, m. ( ), “comparing crm architectures”, strategic research service of patricia seybold group, boston kramer, m. ( ), “customer data mining”, strategic research service of patricia seybold group, boston link, j. and hildebrand, v. ( ), database marketing and computer aided selling, verlag vahlen link, j. and hildebrand, v. ( ), verbreitung und einsatz des database marketing und cas, verlag vahlen messner, w. ( ), “kundenorientierung als herausforderung für das kampagnenmanagement von banken“, in: hollway, s. (ed.), bankwesen- , micg publishing and european financial management & marketing association (efma) nelson, s. and kirkby, j. ( ), “seven key reasons why crm fails”, gartner group, research note com- - , / / porter, m. and millar, v. ( ), “how information gives you competitive advantage”, harvard business review, pp. - , july-august salmen, s. and ruhland, m. ( ), “elektronische marketing-kampagnen – http://www.ingentaselect.com/rpsv/cgi-bin/linker?ext=a&reqidx= - () : l. [aid= ] http://www.ingentaselect.com/rpsv/cgi-bin/linker?ext=a&reqidx= - () : l. [aid= ] http://www.ingentaselect.com/rpsv/cgi-bin/linker?ext=a&reqidx= - () : l. [aid= ] wolfgang messner zwischen e-privacy und electronic customer care”, Öba, pp. - silva, r. ( ), “growing lifetime value through marketing and analytics in financial services”, presentation at the gartner crm summit, london, april srivastava, j., wang, j., lim, e. and hwang, s. ( ), “a case for analytical customer relationship management”, in: chen, m., yu, p. and liu, b. (eds.), pakdd , lnai , springer-verlag, pp. - stone, m. and findlay, g. ( ), “data chaos – a court case waiting to happen”, international journal of customer relationship management, pp. - , september/october stone, m., foss, b., henderson, i., irwin, d., o’donnell, j. and woodcock, n. ( ), “the quality of customer information management in customer life cycle management”, journal of database marketing, vol. , , pp. - yang, q., yin, j., ling, c. and chen, t. ( ), “postprocessing decision trees to extract actionable knowledge”, proceedings of the third ieee international conference on data mining, icdm’ directive / /ec of the european parliament and of the council of october on the protection of individuals with regard to the processing of personal data and on the free movement of such data, official journal , pp. - , / / charter of fundamental rights of the european union, /c / , official journal of the european communities, / / about the author wolfgang messner is a senior management consultant with softlab gmbh in frankfurt. his focus is on the design and implementation of crm- instruments for financial institutions, establishing customer oriented process architectures, deriving functional requirements and executing system evaluations. he has had similar positions in the area of crm with other leading consulting companies. earlier he was a project manager with deutsche software (india) ltd. in bangalore and a business analyst with deutsche bank ag in frankfurt. he holds a ph.d. in economics (dr. rer. pol.) from the university of kassel (germany), an m.b.a. from the university of wales (u.k.) and a master’s degree in computing science (dipl.-inform.) from the technical university munich (germany). he has published several articles with magazines and books and is a frequent speaker on international conferences. weak radiative decays of hyperons and of charm and beauty baryons ∗ paul singer department of physics, technion-israel institute of technology, haifa, israel a review is presented of the weak radiative decays of baryons. it includes an analysis of the possible contri- butions of electromagnetic penguins to these decays, a survey of the difficulties still encountered in the sector of hyperon decays and a short account on some new developments on this topic. the theoretical treatments on charm and beauty baryon decays are summarized, with a good outlook for their detection. . introduction although hyperon decays have been under scrutiny for some three decad the subject still carries the burden of a major puzzle and of dis- crepancies between existing data and a variety of theoretical models [ , ]. at the other end of quarks spectrum, there are no data yet on weak radiative decays of heavy baryons; however, esti- mates [ - ] for some of these modes allows us to anticipate optimistically their future detection. in the (s,d,u) sector, the interesting weak ra- diative processes are two-body decays. these de- cays proceed with branching ratios of the order of ( − )× − , like Σ+ → pγ, Λ → nγ, Ξ → Σ γ, or of the order − , like Ξ− → Σ−γ and the expected Ω− → Ξ−γ[ ]. the three-body de- cays Λ → pπ−γ, Σ+,− → nπ+,−γ proceed as expected for inner bremsstrahling processes with branching ratios close to − and are not of our concern here. on the other hand, the two- body exclusive heavy baryon weak radiative pro- cesses like Λb → Λ γ, Ξ−b → Ξ−γ are not nec- essarily dominating the radiative channel and as we shall see one expects these modes to be sub- stantially smaller than the inclusive ones, e.g. br[Λb → x(s)γ] >> br[Λb → Λ γ]. never- theless, the study of the exclusive channels could provide important physical insights. these weak radiative processes result from an interplay of electroweak and gluonic interactions. presently, their theoretical treatment requires the inclusion of separate short-distance (sd) and long ∗research supported in part by a grant from the ministry of science and the arts and by the fund for promotion of research at the technion. distance (ld) contributions [ , , , ]. the es- timate of the relative size of the two types of processes is an issue to be determined for every specific process. if, for instance, one is confi- dent that in a certain process the long-distance emission is a rather small perturbation, like in b → x(x)γ, b → k∗γ, such processes may be assigned the strategic role of testing the standard model [ , ] as well as the testing of theories be- yond it [ ]. the next section surveys the possible role of the sd single-quark transition q → qγ in the weak radiative decays of strange, charm and beauty baryons. . electroweak penguins in baryon radiative weak de- cays at the quark level there are three types of pro- cesses which contribute to the weak radiative de- cays of baryons, classified [ , ] as single-, two- , and three-quark transitions. the two-quark transition corresponds to w− exchange, with the photon radiated by the participating quarks, and it is essentially a long-distance process. the three-quark transition, where the quark not par- ticipating in w-exchange radiates a photon, is strongly suppressed [ ]. the single-quark tran- sition involves a sd contribution due to the elec- tromagnetic (em) penguin diagrams [ , , ] as well as possible ld contributions [ , ]. before turning to the role of the em pen- guins in the weak radiative baryon decays, one should mention the powerful analysis of gilman and wise (gw)[ ]. in their paper, gw checked the hypothesis that all weak radiative hyperon decays in the -multiplet of su( ) are driven by the single-quark transition s → dγ. they de- termined the strength from the Σ+ → pγ decay and proceeded to calculate from this the expected branching ratios for Λ → nγ, Ξ → Σ γ, Ξ → Λγ, Ξ− → Σ−γ, Ω− → Ξ−γ and Ω− → Ξ−∗γ. their predictions exceed the experimental rates by one or two orders of magnitude for the vari- ous decays. thus, the hypothesis that all these decays proceed via the single-quark transition is untenable. however, it must be stressed that the analysis of gw does not preclude substantial con- tributions from s → dγ, whether sd [ , ] or ld [ ], in only some of the hyperon radiative decays. in the standard electroweak model, the flavour- changing qqγ vertex with the q,q quarks on the mass-shell has the form Γµ = e π gf√ (q) ∑ λ v ∗λqvλq[f ,λ(k )(kµk/ − k γµ) − γ + f ,λ(k )iσµνk ν(mq + γ + mq − γ )](q). ( ) f (q ) and f (q ) are the charge radius and mag- netic form factors respectively, calculated [ ] in electroweak theory in terms of masses of quarks and w ; vab are cabibbo-kabayashi-maskawa (ckm) matrices. for (sdγ) and (bsγ) one has λ = u,c,t and for (cuγ) the contribution is from λ = d,s,b. the f term does not contribute to decays with real photons. it is, however, relevant in de- cays involving leptons like b → x(s)`+`− [ ], Σ+ → p`+`− [ ], Ω− → Ξ−`+`−[ ]. in this pa- per we restrict our discussion to decays with real photons, to which only f contributes. the quantity of physical interest is the qqγ ver- tex with qcd corrections. the effective hamilto- nian has the form heff = − gf√ λ ∑ ci(µ)oi(µ) ( ) where λ represents symbolically products of ckm matrices, oi(µ) is a complete set of dimension- six operators and ci(µ) are wilson coefficients. explicit expressions for the strange, charm and beauty sectors are given in refs. [ ], [ ] and [ ] respectively. o , are current-current opera- tors, o − o are strong penguin operators and o ,o are magnetic operators, of em and gluonic type respectively. in particular the em penguin operator required by eq. ( ) has the form o = e π (q̄)ασ µν[mq( + γ ) + mq( − γ )](q)αfµν . ( ) the application of the qcd corrections using the renormalization group equations endows ( ) with a coefficient ceff , which is a linear combi- nation of ci(µ) and has been calculated for all three sectors, at least to leading order. we are thus in a position to determine quantitatively the contribution of the em penguin to the baryonic radiative weak decays. in the strangeness sector, the replacement by the qcd-corrections of a quadratic gim cancel- lation by logarithmic dependence, increases f by about three orders of magnitude [ , ]. the value of ceff (sdγ) has been reevaluated recently with better accuracy [ , ]. using the new value we estimate the sd contribution to the typical pole decay Σ+ → pγ and to the decays which have been singled out [ ] as potential windows to s → dγ, namely Ω− → Ξ−γ and Ξ− → Σ−γ. using wave functions of ref. [ ] we find Γ(Σ+ → pγ)sds→dγ/Γ(Σ+ → pγ)exp = × − ( ) hence in hyperon radiative decays driven by ld poles the s → dγ transition does not play a no- ticeable role. on the other hand, one finds Γ(Ω− → Ξ−γ)sds→dγ = . × − ev . ( ) using the recently determined [ ] upper limit Γ(Ω− → Ξ−γ)exp < . × − ev one concludes [ ] that in this decay the amplitude ratio sd/ld is larger than / . obviously, this is a remark- able result. a similar calculation for Ξ− → Σ−γ gives Γ(Ξ− → Σ−γ)sds→dγ = . × − ev , ( ) which indicates a contribution of sd of about % in the amplitude of this decay. the transition c → uγ has been treated in detail, including qcd corrections, only recently [ ]. contributions from all three quark loops are comparable in size, like in the strangeness sector. likewise, the qcd corrections enhance also here enormously the transition, leading to a c → uγ width which is increased by five orders of magni- tude. however, even with increased strength the c → uγ em penguin is too small to play a role in weak hadronic radiative decays. the b → sγ transition has been treated in great theoretical detail [ , ]. in this case, the contri- bution of the t-quark loop is strongly dominant so that other contributions are usually omitted. the recent measurements by cleo of b → k∗γ[ ] and b → x(γ [ ] confirm the original expecta- tions [ ] that these modes are dominated by the em penguin transition b → sγ. we expect there- fore b → sγ to play a central role also in beauty baryon decays [ ]. hence, the role of the sd q → qγ transition in the baryonic weak radiative decays is of differ- ent nature in each of the three sectors: it is to- tally negligible in the charm sector, it dominates the appropriate decays in the beauty sector, and plays a modest role in some of the hyperon decays like Ω− → Ξ−γ and Ξ− → Σ−γ. . the hyperon sector the amplitude for the transition b(p) → b′(p′) + γ(k) is m(b → b′γ) = iegf ū(p′)σµν(a + bγ )� µkνu(p) ( ) where a(b) are the parity-conserving (-violating) amplitudes. the angular distribution of the de- cay is characterized by an asymmetry parameter αh, given by αh = re(a ∗b)/(|a| + |b| ) . ( ) table summarizes the experimental situation, based on ref. [ ] except for the entry on Ω− → Ξ−γ which is based on a new experiment [ ]. the recent analysis on the Σ+ → pγ width based on events [ ], not included in table , gives br(Σ+ → pγ) = ( . ± . ± . )× − . a puzzling feature is the large negative asym- metry detected in Σ+ → pγ. according to hara’s theorem [ ], in the limit of su( )-flavour symmetry the pv-amplitudes in Σ+ → pγ and Ξ− → Σ−γ should vanish, causing a vanishing asymmetry. many articles have been devoted to this question as exemplified by ref. [ ]. it has also been argued [ ] that in a quark description the hara theorem does not hold and the problem could lie in the “translation” of the quark basis to the hadronic world. so far, there is no convincing explanation for this large su( )-breaking. a large number of models have been construc- ted to treat the processes of table , most of them attempting a “unified” picture for the ra- diative hyperon decays. among these models, there are pole models [ ], quark models [ ], skirmion models [ ], vector meson dominance models [ ] and chiral models [ ]. in many of these attempts, one accomplishes firstly a fit to the well measured Σ+ → pγ mode, and predic- tions are made for other decays, though refs. [ ], [ ] do not follow this pattern. unfortunately, none of the existing models can reproduce simul- taneously all the features in table . in fact, comparing various models (see, e.g. table . of ref. [ ] and table ii of ref. [ ]) one finds strong disagreements for the yet unmeasured quantities. in the following, we restrict ourselves to an anal- ysis of the better understood physical features in these decays. the analysis of section has shown that the contribution of sd emission is negligible in the four decays proceeding at the − level, namely Σ+ → pγ, Λ → nγ, Ξ → Σ (Λ )γ. it also can account for only a fraction of the decays proceeding at the − level or lower, Ξ− → Σ−γ, Ω− → Ξ−γ, Ω− → Ξ∗−γ, as already established for Ξ− → Σ−γ[ ]. thus, in all hyperon radiative decays the ld emission plays the predominant role. a further dynamical distinct arises from the valence quark structure of the hyperons and the explicit form of h∆s= eff (eq. [ ]). for the above group of four decays heff induces pole diagrams [e.g. Σ → (p,n∗) → pγ, etc.], which dominate over multiparticle intermediate states. a suitable combination of the + baryons and − resonance poles can lead to large asymmetries. however, the table the experimental status of the hyperon radiative decays decay branching ratio( − ) asymmetry parameter Σ+ → pγ . ± . − . ± . Λ → nγ . ± . Ξ → Σ γ . ± . . ± . Ξ → Λ γ . ± . . ± . Ξ− → Σ−γ . ± . Ω− → Ξ−γ < . Ω− → Ξ−∗γ poor knowledge of some of the couplings involved leads to a widely divergent spectrum of predic- tions. the second group of three decays involves par- ticles Ω−(sss), Ξ−(ssd), Σ−(sdd) with no u- valent quark, i.e. there are no w-exchange di- agrams to generate poles. these decays will then proceed via two-hadron intermediate states. glu- onic penguins may also contribute; explicit calcu- lations [ ] indicate that such penguin contribu- tions are considerably suppressed. thus, from a dynamical point of view, there are two distinct groups: the “pole decays” (Σ+ → pγ, Λ → nγ, Ξ → Σ γ, Ξ → Λ γ) and the “non-pole decays” (Ξ− → Σ−γ, Ω− → Ξ−γ, Ω− → Ξ∗−γ), which are driven by different mech- anisms. as an example of a “non-pole” calcula- tion we mention Ξ− → Σ−γ [ ], where the main ld contribution is due to the (Λπ−) intermediate state. the imaginary part of eq. ( ) is then imm(Ξ− → Σ−γ) = ∫ d k ( π) δ(k − m π)δ[(p − k) − m Λ]m(Ξ− → Λπ−) · t (π−Λ → γΣ−) ( ) giving [ ] imald = . mev, imbld = − . mev. for the real part, dominated by an infrared log divergence in the chiral limit, one finds reald = , rebld = − . mev. including uncerta one obtains [ ] Γ(Ξ− → Σ−γ) Γ(Ξ− → all) = ( . ± . ) × − ; αh(Ξ − → Σ−γ) = − . ± . . ( ) the value for the width agrees well with experi- ment; the measurement of the asymmetry is re- quired to confirm the physical picture. . a vector meson dominance approach for long distance transitions q → qγ a new approach to the calculation of the ld contributions to the radiative decays b → s(d)γ has been suggested recently [ ] and was applied to s → dγ and hyperon radiative decays in ref. [ ]. the basic idea is to calculate the ld emis- sion via the t-channel, assuming the vector meson dominance (vmd) of the hadronic electromag- netic current [ ]. a hybrid approach is employed in converting from the nonleptonic hamiltonian expressed in terms of quark operators to the pro- cess q → qv → qγ. it should be mentioned that an older “s-channel” attempt to calculate the ld contribution to s → dγ [ ] uses a problematic mixture of particles and quarks on equal footing in intermediate loops. let us present the new approach [ , ] by considering the relevant o ,o operators in the ∆s = sector of eq. ( ) h∆s= eff = gf√ ∑ η=u,c,t vηsv ∗ ηd(c ,ηo ,η + c ,ηo ,η) + h.c. ( ) o ,η = d̄γµ( − γ )ηβη̄βγµ( − γ )s , ( a) o ,η = d̄γµ( − γ )ηη̄γµ( − γ )s . ( b) using factorization, one obtains the amplitude for q → qv proportional to a gv , where 〈v (k)|η̄γµη| 〉 = igv (k )�+µ (k) and a = c + c n , n being the number of colors. for the hyperon decays, the η = t contribution is negligible and using vcsv ∗ cd ' −vusv ∗ud and the gordon decomposi- tion to extract the transverse part, one has a s→dγ ld = − egf√ vcsv ∗ cda (µ ) [ ∑ i g ψi ( ) m ψi − g ρ( ) m ρ − g ω( ) m ω ] . m s − m d d̄σµν(msr − mdl)sfµν . ( ) a phenomenological value a (µ ) ≥ . is as- sumed [ ]. ms, md are constituent quark masses, r,l projection operators and the sum- mation covers the six narrow −ψ states. the Ω− → Ξ−γ decay is calculated [ ] from ( ) using the formalism of ref. [ ]. using the experimental bound [ ] of Γexp(Ω− → Ξ−γ) < . × − ev one obtains the relation |cvmd| = ∣∣∣∣∣ Σi ∑ i g ψi ( ) m ψi − g ρ( ) m ρ − g ω( ) m ω ∣∣∣∣ < . gev . ( ) the relation ( ) represents a remarkable cancel- lation at the % level. it also determines∑ i g ψi ( )/m ψi = . ± . gev , implying a strong k dependence in the ψi − γ couplings which reduces their value by a factor of ' from k = m ψi to k = . this conclusion agrees well with independent determinations of gψi ( ) from photoproduction and decays [ ]. we expect |cvmd| to be quite close to the up- per limit value ( ), which in turn implies that br(Ω− → Ξ−γ) should be close to the exper- imental upper limit of table . the two-body intermediate states contribute [ ] to the br of this decay only . × − . the application of this approach to Ξ− → Σ−γ gives for the ld contribution to the rate from s → dv an upper limit of %. for a pole decay like Σ+ → pγ the same contribution is less than %. these values confirm the consistency of the dynamical picture discussed in this section. . charm baryon decays charm baryons containing one c quark are usu- ally classified according to the su( ) representa- tion of the two light quarks, which can form a symmetric sextet (with spin ) or an antisym- metric antitriplet (with spin ). the spin an- titriplet is composed of b̄ c (Λ + c , Ξ + c , Ξ c). the sextet baryons have spin (b c ) or spin (b ∗c ). the particles forming it are (Σ++c , Σ + c , Σ c, Ξ ,+ c , Ξ, ? Ω c). the b̄ c particles and Ω c decay weakly, while the rest of sextet particles decay strongly (Σ++,+, c → Λ+c π+, ,−) or electromagnetically (Σ+c → Λ+c γ, Ξ,+, c → Ξ+, γ. in the following, we shall consider only two-body weak radiative decays of charm baryons. the sd contribution from c → uγ to the ra- diative decays was shown to be negligible [ ], hence the main mechanism for the decays is w-exchange. since the radiative decays are “cleaner” than other weak multiparticle decay channels of bc to strongly interacting particles, one may hope that their estimate will be quite reliable. we start our considerations by firstly classifying these decays according to their ckm strength: ckm allowed decays (∆c = ∆s = − ): Λ+c → Σ+γ; Ξ c → Ξ γ. ckm forbidden decays (∆c = − ; ∆s = ): Λ+c → pγ; Ξ+c → Σ+γ; Ξ c → Λ(Σ )γ; Ξ c → Ξ γ. ckm doubly-forbidden decays (∆c = −∆s = − ): Ξ+c → pγ; Ξ−c → nγ; Ω c → Λ (Σ )γ. the photon energy in these decays is consider- ably larger than in the hyperon decays, ranging between mev in Λc → Σ+γ to mev in Ω c → Λγ. kamal has pioneered [ ] this field by calcu- lating Λ+c → Σ+γ from two-quark w-exchange bremsstrahlung transitions of type c+d → s+u+ γ. summing all relevant diagrams one obtains an effective hamiltonian which is used to calculate the amplitudes a,b of eq. ( ). using harmonic oscillator wave functions for the baryons involved, a branching ratio of nearly − is obtained. up- pal and verma [ ] have improved the relativistic corrections of this calculation and have also intro- duced strong flavour dependence in the harmonic oscillator wave functions. the results of their two table . theoretical estimates for charm baryon decays branching ratio ( − ) asymmetry decay mode ref. [ ] ref. [ ] ref. [ ] ref. [ ] ref. [ ] ref. [ ] ref. [ ] i ii i ii Λc → Σ+γ . . . . - . . - . Ξ c → Σ γ . . . - . - . - . models, together with an updated value of ref. [ ] and results from a heavy-quark effective theory calculation [ ] with c and s quarks as heavy are presented in table for the ckm allowed decays. branching ratios for the ckm-forbidden de- cays Λ+c → pγ, Ξ+c → Σ+γ, Ξ c → Λγ, Ω c → Ξ γ were also estimated in ref. [ ] and found to be generally of the order of − . finally, we comment on the weak radiative decays of heavy baryons with several c quarks. among these, of particular interest is Ξ+cc → Ξ+c γ which is ckm allowed and expected with a − branching ratio. there are also a couple decays which cannot proceed via w-exchange. these are Ξ++cc → Σ++c γ and Ω++ccc → Ξ++cc γ, which could be driven by the c → uγ transition. since the sd contribution is very small, these decays would constitute a direct window to the ld c → uγ pro- cess, or possibly to effects beyond the standard model. . beauty baryon decays as it was explained in section , the sd con- tribution plays a prominent role in the b-sector. therefore, we shall classify the beauty baryon two-body weak radiative decays as follows: (a) sd decays driven by the em penguin b → sγ, which includes Λ b → Λ γ; Λ b → Σ γ; Ξ b → Ξ γ; Ξ−b → Ξ−γ; Ω−b → Ω−γ. (b) ld decays which are described on the quark level by two-quark w-exchange transitions accompanied by photon radiation. to this group belong Λ b → Σ cγ; Ξ b → Ξ cγ; Ξ b → Ξ, c γ. the decays in both groups are ckm doubly-forbidden, the matrix el- ement being proportional to vtbv ∗ts ∼ λ for group (a) and to vudv ∗bc ∼ λ for group (b). the pho- ton energies are in the several gev range, e.g. eγ = . gev for Λ b → Λ γ. theoretical calculations for these decays were performed only recently [ , ]. for group (a) the transition amplitude for bi → bfγ is given by the short-distance qcd-corrected o operator m(bi → bfγ) = igf√ e π ceff vtbv ∗ tb� µkν 〈b̄f|s̄σµν[mb( + γ ) + ms( − γ )]b|bi〉 ( ) where cefff = . [ , ]. the ld contribution to the b → sγ transition is estimated to be at the level of a few percent only [ , ], which al- lows us to neglect it. the authors of ref. [ ] use two methods to treat the Λb → Λγ decay, - the heavy quark symmetry scheme with both b and s treated as heavy, and the mit bag mo in the first method, they obtain for the a,b amplitudes of eq. ( ) a,b = ceff √ π vtbv ∗ ts ( ± ms mb − Λ̄h ms ) ξ(v · v′) ( ) where ξ(v·v′) is the isgur-wise function and h is a function of v·v′. allowing for reasonable variation of the various parameters involved, cheng et al. [ ] conclude that br(Λ b → Λ γ) = ( . − . ) × − ( ) ¿from their amplitude, one obtains αh(Λ b → Λ γ) = . . in the heavy s quark limit, Λ behaves as an an- titriplet heavy baryon while Σ as a sextet heavy baryon. Λ b belongs to an antitriplet. accord- ingly, b → sγ will not induce in the limiting case Λ b → Σ γ which is a sextet-antitriplet transition and one is led to Γ(Λ b → Σ γ) << Γ(Λ b → Λ γ) ( ) the other decays of group (a) are more difficult to treat (several heavy quarks baryon). in any case, branching ratios somewhat smaller than in eq. ( ) are expected, also due to wave function overlap suppression especially in Ω−b → Ω−γ. for the transitions of group (b) an effective lagrangian is constructed [ ] from the diagrams of the w-exchange bremsstrahlung processes b + u → c + d + γ, b + d̄ → c + ū + γ. branching ratios smaller by at least one order of magnitude than in group (a) are obtained [ ], even if max- imal overlap for the static bag wave functions is assumed: br(Ξ b → Ξ cγ) = . × − ; αh = − . br(Ξ b → Ξ, c γ) = . × − ; αh = − . br(Λ b → Σ cγ) = . × − ; αh = − . the basic decay mechanism b → sγ actually leads to a multitude of exclusive states in the ra- diative Λb decay, like Λb → Λ( )γ, Λ( )γ, Λ(nπ)γ, Ληγ, Λη′γ, etc. hence it is of interest to estimate the expected Λ b → x(s)γ branching ratio and the percentage of it of the lowest exclu- sive mode, Λ b → Λ γ. we use the measured [ ] b → x(s)γ to calculate Γ(b → sγ) = ( ± . )× − ev. assuming Γ(Λ b → x(s)γ)/Γ(Λb → all) ' Γ(b → sγ)/Γ(Λb → all) and the measured Λ b life-time[ ] we estimate Γ(Λ b → x(s)γ) Γ(Λb → all) = ( . ± . ) × − . ( ) hence, the calculations presented above lead to Γ(Λ b → Λ γ) Γ(Λb → x(s)γ) ' ( . ± . )%. ( ) the figure we obtained is not very different from the mesonic sector, where one has [ , ] Γ(b → k∗γ)/Γ(b → x(s)γ) = . ± . an analysis [ ] of the angular distribution of the photon in Λ b → x(s)γ with polarized Λ b, using the heavy quark effective scheme, shows that deviations from free quark decay are gener- ally small and are significant mostly for photons emitted in the forward direction with respect to Λ b spin. however, as a consequence of the func- tional form of the em penguin the photons are emitted preferentially backwards. . concluding remarks we highlight here several points, some of which are of direct relevance to forthcoming and con- templated experimental programmes: # as a result of the theoretical activity of last few years, a clear picture emerges on the the im- portance of short-distance radiation in the weak radiative decays of baryons. thus, the electro- magnetic penguin q − qγ (with gluonic correc- tions) plays a major role in the beauty sector, dominating processes like Λb → x(s)γ, Λb → Λγ. the charm penguin c → uγ is too weak to play any noticeable role in charm baryon radiative de- cays, while the strange penguin s → dγ occupies an intermediate position, contributing to a pos- sibly detectable extent in a few hyperon decays (Ω− → Ξ−γ, Ξ− → Σ−γ, Ω− → Ξ∗−γ). # the measurements of the rate and asymme- try parameter of Ω− → Ξ−γ should be given high priority, since there is good probability that both sd and ld radiation contributes measurably to it. this decay could constitute the main desired window to the em penguin in the strangeness sec- tor s → dγ, in addition to providing interesting information on couplings of vector mesons to pho- tons from the ld contribution. # it is difficult at present to favour any of the competing models describing pole hyperon decays like Σ+ → pγ, Ξ → Σ γ, etc. since the var- ious models diverge mostly in the prediction of the asymmetry parameter, good measurements of this parameter in Λ → nγ, Ξ → Λγ and Ξ → Σ γ should finally alllow one to resolve the unsettled situation. # the measurement of the asymmetry param- eter in the decay Ξ− → Σ−γ will distinguish be- tween the dynamical picture [ , ] for non-pole decays which leads to eq. ( ), and alternative mechanisms [ - ]. # theoretical estimates indicate that charm baryon ckm allowed radiative decays will oc- cur with a branching ratio of ∼ − , making the search for these decays a realistic proposition. one expects br(Λ+c → Σ+γ) = + − . × − , br(Ξ c → Ξ γ = ( . ± . ) × − . the ckm- forbidden decays, like Λ+c → pγ, Ξ c → Λ(Σ )γ, Ξ+c → Σ+γ, Ω c → Ξ γ are expected to occur with branching ratios of − or less. # beauty baryons have detectable weak ra- diative decays induced by short distanc electro- magnetic penguins. the inclusive decay Λb → x(s)γ is expected to have a branching ratio of ( . ± . ) × − . the most frequent exclu- sive mode is probably Λb → Λγ expected to oc- cur with a branching ratio of ( ± . ) × − . on the other hand, Λ b → Σ γ is expected from heavy quarks symmetry considerations to be be much smaller. radiative decays to charm baryons Λ b → Σ cγ, Ξ b → Ξ cγ, Ξ b → Ξ, c γ are expected in the − − − range. references . a detailed review on the experimental and theoretical states of weak radiative decays of hyperons is: j. lach and p. zenczykowski, int. j. of mod. phys. a (in press). . p. singer, in “puzzles on the electroweak scale” (world scientific, eds. z. ajduk, s. pokorski and a.k. wroblewski) p. 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(in press). sÖz varliĞi turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer Şİİr semasinin yegÂne yildizi; gÜzeller sultani mehmet gÜrbÜz  Özet divan şiirinin merkezinde sevgili vardır. bu sevgili, sanatsal bir kimliğe büründürülmüş böylece sosyal hayata dair bütün yüklerinden, eksikliklerinden ve kusurlarından arındırılarak idealize edilmiştir. divan edebiyatına mensup şairler de özelliklerini geleneğin belirlediği bu sevgiliyi, yine geleneğin belirlediği mecaz ve teşbihler dünyası içerisinde, ortak bir kelime kadrosuyla tasvir etmişlerdir. sevgili etrafında oluşturulan bu imaj dünyasına ait hususların gelenekselleşme sürecini konuyla ilgili farklı türlerde yazılmış eserlerden takip etmek mümkündür. bu çalışmada kâbilî’nin sultân-ı hûbâna münâsib eşˋâr adlı şiir mecmuası merkeze alınarak sevgilinin güzellik unsurları üzerine yazılmış eserler ele alınacaktır. anahtar kelimeler: divan edebiyatı, şiir mecmuası, sevgilinin güzellik unsurları. the only stars of poem’s sky; sultan of beauties abstract beloved stands at the centre of divan poetry. this beloved is defined by an artistic identity and so is idealized by being purified from all charges, deficiencies and faults, in short, everything related to social life. and the poets of divan literature have described this beloved, whose characteristics have been determined by tradition, with metaphors and comparisons. it is possible to follow this process of making of tradition on the peculiarities of the imaginary world around the beloved from the works written in different kinds. in this study, the works written on peculiarities of beloved, by taking kâbilî’s poetry  okutman, bozok Üniversitesi, meingurbuz@hotmail.com mailto:meingurbuz@hotmail.com Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer periodical titled sultân-ı hûbâna münâsib eşˋâr to the centre, will be evaluated. key words: divan literature, poetry periodical (mecmua), elements of beloved’s beauty. divan edebiyatı, kuralları önceden belirlenmiş olan bir geleneğe sahiptir. Çerçevesi fars edebiyatından yararlanılarak oluşturulan bu gelenek, şekle ait unsurları kurallara bağladığı gibi muhtevayı da sınırlandırır. divan edebiyatı geleneğine giren bir şair, nazım şekillerinden divan tertibine kadar gelenek tarafından tespit edilmiş şekil hususiyetlerine uymak zorundadır. yine gelenekçe belirlenmiş olan konu, hayal dünyası ve imaj sistemi içerisinde şiirini inşa etme durumundadır. bu dünya içerisinde geleneğin belirlediklerini reddederek şahsî bir yol çizme anlayışı yoktur. elbette sanatın doğası gereği, bir sanatkâr olan divan şairi de özgünlük peşinde koşacaktır. ancak divan edebiyatı geleneği içerisindeki şairlerin bu özgünlük arayışları –çok az istisnanın dışında- yine geleneğin çizdiği çerçeve içerisinde yürür. geleneğin bu şekilde varlığını sürdürebilmesi, divan edebiyatı dairesine girmeye çalışan şair adaylarının geçmek zorunda oldukları eğitim süreciyle ilgilidir. Şair adayı öncelikle üstat şairlerin şiirlerini okuyup ezberler, onlardan geleneğin istediği edebî terbiyeyi alarak şiir meşk etmeye başlar. ancak bu uzun ve meşakkatli uğraşı sonrasında kendi edebî kimliğini bulmaya çalışır (ayrıntılı bilgi için bkz. akün , - ; köksal ; kurnaz ). Şair bundan sonraki edebî hayatı boyunca, bahsedilen eğitim sürecinde edindiği birikimi kullanır. Şiirinde ele alacağı konuyu, bunu işlerken kullanacağı teşbih, mazmun gibi ifade unsurlarını geleneğin inşa ettiği birikim içerisinden seçer. Ö. faruk akün‟e göre geleneğin sunduğu bu teşrifat gereğince sosyal kimliğinden farklı olarak ikincil bir şair kimliği oluşturur ve şiirlerinde bu kimliğin ağzından geleneğin kendisine öğrettiklerini terennüm eder ( , ). divan şiiri geleneğinin şaire biçtiği en önemli görev, bu “teşrifatın” gerektirdiği şekilde bir âşık kimliğine bürünerek sevgiliyi övmesidir. Çünkü divan şiirinin merkezinde sevgili vardır. Şair, sosyal statü, yaş, cinsiyet gibi bütün ayrımların üzerine çıkan bir aşk anlayışıyla tüm vasıfları gelenekçe belirlenmiş olan sevgiliyi yine onun öğrettiği şekilde sever ve bunu dile getirir. sevgilinin güzellik unsurlarının gelenek içerisinde nasıl belirlendiğini ya da en azından süreç içerisinde nasıl şekillendiğini mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer divanlardan ve özellikle de bu konu üzerine yazılmış müstakil eserlerden takip etmek mümkündür. bu konuda üzerinde ilk durulması gereken tür, şairlerin sevgilinin vasıflarını hangi sıfatlarla nasıl övdüğü ya da övmesi gerektiği üzerine, teşbihler sözlüğü anlayışıyla hazırlanmış olan eserlerdir. bunlardan en önemlisi Şerâfeddin râmî‟nin enisü’l-uşşâk ( / )‟ıdır. fars edebiyatında türünün ilk örneği olan ve arap edebiyatında yazılmış aynı türdeki eserlerden oldukça önemli farklılıklar gösteren bu çalışma, kendisinden sonra yazılacak eserlere kaynaklık etmiştir (Şerafeddîn râmî ). bu edebiyat içerisinde xvii. yüzyıl şairi fasîhî-i herevî‟nin mecazlar mecmuası ile nizamüddin-i kandehârî‟nin kavâ’idü’l-urefâ ve Âdâbu’ş-Şuˋarâ ( / )‟sı gibi eserlerin kaleme alınması, bu eserlerden elde edilen birikimin sözlüklere yansıması ve “serâpây” denilen özel bir türün doğması bu kabildendir (ayrıntılı bilgi için bkz. Şafak , - ). söz konusu eser, fars edebiyatında olduğu kadar divan edebiyatında da yankı bulmuştur. kutbüddin ahmet‟in hevesnâme ( / )‟si, xvi. yüzyıl şairi muîdî‟nin miftâhu’t-teşbîh‟i (erünsal , - ) ile sürûrî‟nin bahrü’l-maˋârif ( / )‟inin en hacimli kısmını teşkil eden “teşbîhât ve mesâ‟il-i enîsü‟l-uşşâk beyânındadır” başlıklı bölümü (Şafak , - ) büyük oranda râmî‟nin eserine bağlı kalınarak oluşturulmuştur. bu tür eserlerde, sevgilinin güzellik unsurlarının tasnife tabi tutularak bunlarla ilgili adlandırma, tanımlama ve kavramlaştırma çalışmalarının yapıldığı görülür. bu kavramların bir yandan sözlüklere dayanılarak kelime anlamları tespit edilirken diğer yandan da edebî gelenekte kazandıkları kullanım alanlarının çerçevesi çizilmeye çalışılır. ayrıca edebî gelenek içerisinde sevgili etrafında oluşturulan mecazlar dünyası fars ve türk şiirinden seçilmiş örneklerle desteklenir. bu çalışmalar, genel hatlarıyla râmî‟nin eserine bağlı olmakla birlikte izlenilen yöntem, sınıflandırma ve kullanılan kavramlar bakımından birtakım farklılıklar da gösterir. Örneğin kutbüddin ahmet, farsça kaleme aldığı hevesnâme’sini râmî‟nin eserine nazire olarak yazmasına karşılık tasvir edilen uzuvların sayısını arttırarak (atay , ), sürûrî de bazı bölümler ilave ederek muhtasar bir eser olan enîsü’l-uşşâk‟ı genişletmişlerdir (Şafak , ). benzer farklılıklar şairlerin kullanımlarında da söz konusudur. zira eserlerde işaret edilen kavramlar veya tanımlamalar tüm zamanlar için kuşatıcı olmaktan uzaktır. Çünkü sanatçı, geleneğin belirlediği genel çerçeve içerisinde de olsa sürekli bir yenilik arayışı hâlindedir. dolayısıyla da şairlerin peşinde koştukları orijinal hayal ve Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer söyleyiş arayışlarının sonucu olan kullanımlar, söz konusu kalıpların dışında bir değişikliği ve genişlemeyi de beraberinde getirmiştir. nitekim sevgilinin güzellik unsurlarıyla ilgili mecaz dünyası söz konusu olduğunda şairlerin bir hayli farklı tercihleri olduğu görülür. (bu duruma örnek olması için bkz. tanyıldız , , , , ). benzetmeler sözlüğü olarak düşünülebilecek bu eserlerin dışında, yine sevgilinin güzellik unsurları etrafında teşekkül etmiş mesnevilerden de söz edilebilir. tâcîzâde cafer Çelebi, hevesnâme ( )‟sinin bir bölümünde ideal bir güzelin bütün uzuvlarını yukarıdan aşağıya anatomik bir düzenle bir araya getirme, her uzuv için yapılan betimlemelerden yola çıkarak küçük çapta bir sözlük hazırlama gayreti içerisindedir (atay , - ). hassân‟ın farsçadan tercüme ettiği mihr ü müşterî ( / - )‟si ile kara fazlî‟nin gül ü bülbül ( / - )‟ü de sevgilinin güzellik unsurları etrafında oluşturulmuş mesnevilerdendir. xvi. yüzyıl şairi manastırlı celâl‟in hüsn-i yûsuf adlı eseri de her biri sevgilinin güzellik unsurları üzerine yazılmış gazelden meydana gelir (aksoyak b, - ). bu tür çalışmalar, kavram sınıflandırmasını ve sıralamasını yukarıda bahsedilen belagat merkezli eserlerden almış olmakla birlikte sanatsal bir amaç gütmeleri ve bu amaç doğrultusunda teşbih unsurlarını sıralamak ve ansiklopedik bilgi vermek yerine şiir formunda takdim etmeleriyle farklılık gösterirler. mesnevilerden başka gazel, şehrengiz, bahr-ı tavîl (aksoyak a, ) gibi şiir türlerinde de sevgilinin güzellik unsurlarının ve ona duyulan aşkın merkeze alınması söz konusudur. yukarıdan beri saydığımız eserlerin dışında, sevgilinin güzellik unsurları etrafında oluşturulmuş şiir mecmualarını da yine bu geleneğin devamı olarak değerlendirmek ve burada anmak gerekir. genel anlamıyla mecmua kelimesi, değişik ilgi alanlarından pek çok farklı malzemeyi ihtiva etmeleriyle meydana getirildikleri dönemin tarihine, inanç ve değer yargılarına, sosyal ve kültürel yapısına ışık tutacak nitelikteki eserleri tanımlamak için kullanılan bir terimdir. daha özelde şiir mecmuaları ise çoğunlukla kendileri de şair olan mürettiplerce onların kişisel zevklerine göre derlenmiş farklı tür ve şekildeki şiirleri içinde barındıran eserlerdir (ayrıntılı bilgi için bkz. kut , - ). Şiir mecmuaları, edebiyat tarihi, biyografi, metin neşri (bkz. aydemir , - ) gibi edebiyat araştırmalarının farklı dalları için önemli kaynaklardır. bütün bunların ötesinde şiir geleneğinin nasıl oluştuğunun anlaşılabilmesinde ve metinlerarasılık bağlamında şairler arasındaki mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer etkileşimin ortaya çıkarılabilmesinde önemli bir rol oynarlar. bu çerçevede sevgilinin güzellik unsurları etrafında oluşturulmuş beyitleri ya da şiirleri toplayan mecmualar da geleneğin nasıl oluştuğuna ve değişim gösterdiğine ışık tutacak niteliktedir. xvi. yüzyılda kâbilî‟nin tertip ettiği sultân-ı hûbâna münâsib eşˋâr adlı mecmua , varlığından yaşar aydemir‟in söz ettiği xvii. yüzyılda meydana getirilmiş bir şiir mecmuası ( , - ), xviii. yüzyıl şairi lâzikîzâde feyzullah nâfiz‟in letâifü’l-hayâl adlı mecmuası (demir , - ) bunlardandır. Ömer faruk akün, bunlardan başka sevgilinin beden güzelliği üzerindeki teşbih ve sıfatları sıralayan birtakım listeleri içeren başka şiir mecmualarının varlığından da söz eder (akün , ). bu örneklerden hareketle işaret edilen konu üzerine mecmua tertip etmenin bir gelenek haline geldiği tespiti yapılabilir. bu tür bir mecmua oluşturma geleneğinin içeriğine geçmeden önce sultân-ı hûbâna münâsib eşˋâr adlı mecmua hakkında tanıtıcı bilgi vermek yerinde olacaktır. mecmuanın mürettibinin gerek eserin “müntahabât-ı Şâˋir kâbilî” şeklindeki başlığından gerekse kimi beyitlerin başındaki “kâbilî el-hakîr, bende- i kemter ü kemîne kâbilî” gibi ifadelerden kâbilî olduğu anlaşılmaktadır. tezkirelerde iki kâbilî‟den söz edilir. haklarında çok fazla bilgi bulunmayan şairlerden birincisinin hicri x. asır şairi olduğu, İstanbul‟un molla gürani mahallesi‟nden zuhur ettiği, tasavvuf yoluna girip bir müddet eğitim ve terbiye gördükten sonra buradan ayrılarak mekke, medine, Şam ve halep gibi arap illerinde ikamet ettiği ve rum diyarında seyahat ettiği ve ömrünün sonlarında sağır olduğu kayıtlıdır (kılıç , ; sungurhan , ; tuman , md ). İkincisinin ise ispartalı abdülgani efendi‟nin oğlu yaverizâde mehmet efendi olduğu bilgisi vardır (riyâzî tsz, b). sicill-i osmânî‟ye göre müderrislik yaptığı, ( / )‟de galata mollası sonra selanik mollası olduğu ve Şevval (mart- nisan )‟te vefat ettiği yazılıdır (mehmed süreyya , ). tuhfe-i nâilî‟de ise selanik kadısı olduğu safer (temmuz- ağustos )‟te öldüğü ve mezarının yine burada olduğu kayıtlıdır (tuman , md. ). ancak mecmuanın bu şahıslardan hangisine ait olduğunu şu an için kesin olarak söylemek mümkün görünmemektedir. zira söz doktora tezi olarak üzerinde çalışmakta olduğum bu eseri tespit eden sadık erdem‟e, esere ulaşmamda aracılık eden tez danışmanım İsmail hakkı aksoyak‟a ve alanımızın çok değerli bilim insanı günay kut‟a teşekkür etmeyi bir borç biliyorum. Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer konusu şahıslar hakkında bilgi veren tezkirelerde böyle bir eserden söz edilmez. yalnızca kâfzâde fâizî, tezkiresinin yaverizâde kâbilî Çelebi maddesinde, şairin mecmuasını gördüğünü ve örnek beyitleri oradan aldığını söyler (kâfzâde fâizî tsz, b). bu kayıt söz konusu eserin yukarıda tanıtılan şairlerden ikincisine ait olabileceği ihtimalini güçlendirmektedir. ancak mecmuadaki kâbilî‟ye ait olduğu anlaşılan matla beytinden hiçbirisi ne fâizî‟nin verdiği örnekler içerisinde ne de diğer tezkirelerde yer almaz. Üstelik mecmuada geniş bir şair kadrosuna ait çok sayıda farsça beytin bulunması, arap ve acem diyarını dolaşmış olan İstanbullu kâbilî‟nin eserin mürettibi olabileceğini de düşündürmektedir. ancak bu aşamada eserin mürettibinin kaynaklara girmemiş, farsçayı iyi bilen başka bir kâbilî olabileceği ihtimalini de göz ardı etmemek doğru olacaktır. tezkireler kâbilî‟nin bir divanından ya da başka bir eserinden bahsetmemişlerdir. ancak mecmuasındaki şiirleri ona ait bir divanın olabileceğini düşündürmektedir. zira tezkireler onun mecmuasından da söz etmemişlerdir. Öyleyse kâbilî‟nin tezkirelere girmemiş bir divanının bulunması ihtimali hep vardır. böyle bir divanın ele geçmesi, mecmuanın mürettibinin kimliği konusundaki sorunu da çözecektir. kâbilî‟nin mecmuasının tespit edebildiğimiz tek nüshası, millet kütüphanesi ae manzum - numaralara kayıtlıdır. İki cilt halinde tertip edilmiş bu nüsha, varaktan oluşmaktadır. sayfalarda farklı renklerdeki mürekkeplerle yapılmış eksik numaralandırmaların yanında eserin başından sonuna kadar devam eden tek bir numaralandırma da vardır. bu numaralandırmaya göre eserin ciltlenmesi sırasında yaprakların takdimi ya da tehirinden kaynaklandığı anlaşılan karışıklıklar bulunmaktadır. mecmuanın sayfa düzenindeki bu karışıklığın en azından metnin tamamının ortaya dökülmeden çözüme kavuşturulması mümkün gözükmemektedir. beyitler, sevgilinin güzellik unsurları temelinde sınıflara ayrılmış olduğu için bu karışıklık, sayfalarda yer alan şiirlerin konu başlıklarıyla ilişkilendirilmesi suretiyle çözümlenebilecektir. İçerisine alınan şairlerden hareketle xvi. yüzyıla ait olduğu anlaşılan eserin istinsah tarihi belli olmadığı gibi müntesihi de belli değildir. hemen her şair, mahlasının ses ya da anlam ilgisi çerçevesinde övülürken kâbilî‟nin “el-hakîr, bende-i kemter ü kemîne, erbâb-ı nazmın ayağı toprağıdır” gibi ifadelerle birlikte anılması eserin onun kaleminden çıktığını düşündürmektedir. bir beytin başındaki “terceme-i lâ-nazîr matladır” başlığının farklı bir kalemle yapılan ilavelerle “kâbilî tercemesi lâ-nazîr matladır” şekline dönüştürülmüş olması bu düşüncemizi desteklediği gibi eserin mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer sonradan bir başkası tarafından gözden geçirildiğini de göstermektedir. mecmuanın başındaki “müntahabât-ı Şâˋir kâbilî” ifadesi de eserin bir başkası tarafından gözden geçirildiğinin, ciltlendiğinin ya da en azından ona müdahale edildiğinin bir kanıtıdır. eserdeki kimi beyitlerde sonradan yapıldığı anlaşılan müdahale ve düzeltmeler bulunmaktadır. bu düzeltmelerin elde edilen yeni bilgiler doğrultusunda veya sonraki zamanlarda şairlerin divanlarının yeni nüshalarının görülmesiyle yapılmış olması ihtimali yüksektir. mecmuaya alınan beyitler, çok ayrıntılı ve sistematik bir şekilde sınıflandırılmıştır. sevgilinin yüz, kaş, boy gibi güzellik unsurlarının ana bölümlerini oluşturduğu bu sınıflandırmada alt bölümler de bulunmaktadır. İşlenen hayal, anlamın üzerine kurulduğu mazmun veya şiirlerin birbirine nazire olması gibi etkenlerin bu alt sınıflandırmada etkili olduğu düşünülmektedir. edebiyatımızda sevgilinin güzellik unsurlarını konu edinen eser yazma geleneği hakkında bilgi verdikten ve kâbilî‟nin mecmuasını kısaca tanıttıktan sonra söz konusu eserin gelenek içerisindeki konumunu tespit etmek yerinde olacaktır. bu amaçla öncelikle geleneği oluşturan eserlerde ele alınan unsurları görmek ve buradan hareketle bir kıyaslamaya gitmek gerekecektir. aşağıdaki tabloda belli başlı eserlerde işlenen sevgilinin güzellik unsurlarını görmek mümkündür . e mm h h bm gb mt hy saç saç hüsn ü cemâl kâmet hüsn ü cemâl zülf mûy kâkül alın kaş işk mû işk u hâl kâmet gûş zülf kaş göz mûy cebîn kâkül ü zülf pişânî cebîn cebîn göz bînî cebîn ebrû alın ebrû ebrû ebrû kirpik yanak ebrû Çeşm kulak Çeşm Çeşm Çeşm yüz gûş Çeşm Çeşm kaş gamze bînî müje ayva tüyü leb müjgân müjgân göz müjgân müje gamze ben dehân gamze zülf kirpik bînî rûy Ârız dudak dendân ruhsâr gûş gamze ruhsâr hat ruh diş dil bînî Ârız yüz hâl hâl gûş tablo, aksoyak b, - ‟ten alınmıştır. tablodaki kısaltmalardan e, Şerâfeddin râmî‟nin enisü’l-uşşâk ( / )‟ını; mm, hassân‟ın mihr ü müşterî ( / - )‟sini; h , kutbüddin ahmet‟in hevesnâme ( / )‟sini; h , tâcîzâde cafer Çelebi‟nin hevesnâme ( )‟sini; bm, sürûrî‟nin bahrü’l-maˋârif ( / )‟ini; gb, kara fazlî‟nin gül ü bülbül ( / - )‟ünü; mt, muîdî‟nin miftâhu’t-teşbîh (xvi. yy.)‟ini; hy ise manastırlı celâl‟in hüsn-i yûsuf (xvi. yy.)‟unu karşılamaktadır. Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer ağız zenehdân hat hâl burun gûş leb leb Çene gabgab hâl ruhsâr hat leb dendân dehen boyun gerden leb bînî kara ben dehân zenehdân zekan göğüs dûş dendân dehen tudak zebân gerden gabgab kol bâzû dehân leb dendân dendân sîne gerden parmak bilek zenehdân dendân ağız gabgab engüşt sîne boy dest ü sâid gerden zebân dil zekan sâid miyân bel el ber ü pistân zekan enek gerden kadd dest baldır parmak sâid ü dest ü bâzû zekan boyın bâzû miyân sâid dırnak engüşt ü benân gabgab göğüs sâid sâk pây ber kadd u kâmet gerden bilek dest ser ü pây pehlû miyân sîne parmak engüşt kâmet Şikem sâk bâzû boy nâhun nâf beden ü endâm sâid bil sîne püşt zât-ı mahbûb kef İncik miyân kadd kelâm püşt-i dest mecmû-ı azâ nâf bil asâbi zât-ı mahbûb sâk nâhunhâ söz pây batn nâf miyân pehlû rân (?) sâk kadem yukarıdaki tabloda yer alan eserlerde sevgiliyle ilgili unsurların neredeyse tamamının fiziksel güzelliğe ait olduğu ve yukarıdan aşağıya doğru anatomik bir sıralamayla ele alındığı dikkati çeker. sevgilinin fiziksel yönüyle ilgili olmayan “ışk, kelâm/söz” gibi ancak birkaç hususa yer verildiği görülür. kâbilî‟nin sultân-ı hûbâna münâsib eşˋâr adlı mecmuasında ise derlenen beyitler şu başlıklar altında sınıflandırılmıştır: . laˋl-i rengîne münâsib olan eşˋâr-ı latîf . bu meclis ol kemân-ebrûların tîr-i cefâsıdır . leylî vü mecnûn İle ferhâd u Şîrîn bahsidir mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer . Şîve vü nâza münâsib olan eşˋâr budur . gam u gussa-i firâk u cevr-i cânân meclisidir bu . rakîb-i rû-siyehle hâsılı ağyâr faslıdır . Âftâb u mâh vasfında metâliˋ faslıdır . serv faslıdır bu meclis-i kadd-i cânân . hâne vü kâşâneye lâyık olan eşˋârdır . tîğ ü hançer faslıdır bu gamze-i ebrû-yı yâr . fasl-ı sâz u söz ü makâmât (sâz faslıdır bu meclis nağme-i uşşâkdan) . hammâm-ı pür-safâya münâsib olan eşˋâr budur ki zikr olunur (fasl-ı hammâma münâsib Âb-dâr ebyât-ı pâk) . hat-ı müşgîne münâsib olan eşˋâr-ı safâ . nigâr-ı nâzenîn faslı bu meclis . fasl-ı Âh-ı pür-sûz (Âh faslıdır bu meclis gün gibi meşhûrdur) . kûy-ı cânâne-i dil Âyâ baht-ı bed beyânındadır burada dikkati çeken ilk husus, bölüm başlıklarının şiirsel üslubudur. başlıklarda eserin meydana getiriliş amacına uygun olarak sanatlı söyleyişler tercih edilmiştir. hatta bazı bölümlere daha güzel bir söyleyiş yakalayabilmek için birden fazla başlık konulmuştur. Üzerinde durulması gereken başka bir husus da ele alınan unsurlardır. mecmuada sevgilinin güzellik unsurlarının tümüne yer verilmemiştir. esere alınanlar da anatomik bir sıralamayla sunulmamıştır. diğer eserlerden farklı olarak sevgilinin dudak, kaş, yüz, yanak, boy, gamze, hat gibi fiziksel güzelliklerinin dışında, nazı, işvesi, cevri, nezaketi ve yaşadığı mekân da sınıflandırmaya dâhil edilmiştir. sevgiliye ait bu hususların yanında aşk, âşık, rakip, ayrılığın gamı, kederi ve âşığın ahı ile saz, söz ve hamam tasvirleri gibi unsurların da mecmuada yer aldığı görülür. bütün bu farklılıklar kâbilî‟nin mecmuasını yukarıdaki eserlerden ayırır. hemen şunu da belirtmek gerekir ki eser, “ışk, söz” gibi unsurların işlenmiş olması bakımından kutbüddin ahmet‟in hevesnâme‟si ve sürûrî‟nin bahrü’l-maˋârif‟i ile benzerlik gösterir. mecmuanın niteliğini daha iyi ortaya koyabilmek için bölümlerin içeriğinden genel hatlarıyla bahsetmek ve birkaç örnek beyit vermek faydalı olacaktır. eser sevgili, âşık ve rakip ile ilgili beyitlerin toplanmasından oluşmuştur. bu beyitler yukarıdaki başlıklar Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer altında sınıflandırılmıştır. diğer eserlerde sevgilinin sadece fiziksel güzellik unsurları yer alırken burada ruhsal özelliklerinin de ele alındığı görülmektedir. birinci bölümde fizikî unsurlardan dudağın şekli, rengi, şeker gibi tatlı oluşu, âşığa canlar bağışlaması gibi özellikleriyle ilişkili beyitler seçilmiştir. zîbâ ruhundan oldı lebün ey kamer lezîz gün germ olınca lâ-cerem olur semer lezîz necâtî bir cevâb alabileydüm dehenünden cânâ dil-i bîmârumı ol sâˋat ideydüm ihyâ ˋÂlî bilmez idüm bilmek agzun sırrını düşvâr imiş agzunı dirlerdi yok didüklerince var imiş fuzûlî eserin ikinci bölümünde yine sevgilinin fiziksel güzellik unsurlarından kaş, göz, kirpik gibi uzuvları ile bunların âşığa ettikleri cevr ü cefa üzerine oluşturulmuş beyitler yer almaktadır. bir kemândur dôstum ol kaşlarun mûyı bana kim urur cân u dile bir demde bin tîr-i cefâ figânî kaşlarun yayını kur kim cân olur kurbân ana tîr-i gamzen gizle kim lâzım degül peykân ana muhibbî bakış ile sîneye tîrin kaçan cânân atar ana bir gezden nişân olmaga ˋâlem cân atar sadrî diğer bir bölümde sevgilinin gamzesi ele alınmış, kılıca ve hançere benzeyen bakışlarının âşığı yaralaması ile ilgili beyitler bir araya getirilmiştir. tîgün ile gel şikâf it sînemi mânend-i kâf dönmeyem bâr-ı belâdan ger olursa kûh-ı kâf yahyâ tîg-i mahabbetünle yürek pâre pâredür her pâre tîr-i gamze ile yâre yâredür emrî hancerün aksi nigârâ sîne-i sad-çâkde Şekl-i mâhîdür ki tasvîr eylemişler hâkde münîrî bir başka bölümde sevgilinin serviye benzeyen boyu, servi etrafında oluşan bahçe imajı içerisinde ele alınmıştır. mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer ser-defter-i hûbânsın eyâ serv-i sehî-kad yok sencileyin şimdi güzellerde ser-âmed nâmî serv ile gül çemende ki turup oturdılar bu kadd ü bu ˋizârı yine sende gördiler hayâlî sevgilinin güzelliğinin güneşe ve aya benzetilerek övüldüğü beyitler ayrı bir başlık altında yer alır. ey meh şuˋâˋ sanma ki hüsnünden âftâb barmakların yüzine tutar eyleyüp hicâb emrî subh-ı sâdık togar ol mihr-i dırahşân gelmez kara ahşamlar olur ol meh-i tâbân gelmez meylî-i bursevî ruhlarun kıldı münevver ˋâlemi ey meh-likâ kim bulardan kesb ider şems ü kamer nûr u ziyâ hüsâmî bir başka bölümde sevgilinin ve teninin güzelliği hamamla ilişkili olarak ele alınmıştır. kıldı ol serv seher nâz ile hammâma hırâm Şemˋ-i ruhsârı ile oldı münevver hammâm fuzûlî bir cevân-ı bî-bedel gördüm bugün hammâmda zerrece noksânı yokdur cümleten endâmda adlî diğer bir fiziksel güzellik unsuru olan sevgilinin yanağındaki ayva tüylerinin üzerine kurulmuş beyitler de ayrı bir başlık altında sunulmuştur. hatt u lebün ki hızr u mesîhâ nişânıdur ben hastenün biri eceli biri cânıdur kâmî gam degül bî-hâl olursa hüsnün evrâkında hat resmdür âriflere nâme yazarlar bî-nukat ahmed paşa Ünlü aşk kahramanları leyla ile mecnun ve ferhat ile Şirin üzerinden sevgili ve âşığın hâllerini konu edinen matlalar da eserin ayrı bir bölümünü oluşturur. beni mecnûn bilürler hâlet-i leylîyi bilmezler Çekerler bend-i zencîre nedür sevdâyı bilmezler Şemsî paşa Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer daglar nâle kılup tîşeler itdi feryâd virdüginde gam-ı Şîrîn ile cânın ferhâd sânî deşt-i gamda gördügüm mecnûn-ı nâ-şâd eylemez İtdügüm kârı belâ deştinde ferhâd eylemez figânî eserde ruhsal açıdan sevgiliyi tanımlayıcı bir takım özelliklere de yer verilmiştir. bu çerçevede sevgilinin işveli ve nazlı oluşu ile ilgili beyitler bir araya getirilmiştir. nâz-perver ˋişve-gersin şûhsın tannâzsın dil-rübâlar içre hüsn ü ân ile mümtâzsın nevˋî nedür bu handeler bu ˋişveler bu nâz u istignâ nedür bu cilvelerle şîveler bu kâmet-i bâlâ bâkî cânân odur ki ˋâşık idince ana niyâz her bir niyâzına kıla anun hezâr nâz zarîfî yine sevgilinin bir put kadar güzel olmasının yanında nazenin oluşu da ayrı bir bölümde ele alınmıştır. cânân odur ki nakşı güzel bir nigâr ola hûb u latîf ü nâzük ola şîve-kâr ola Şevkî efendi ol nigârun çeşmi âfet gamzesi gammâz imiş Şehrümüz dil-berlerinden cümleden mümtâz imiş İshâk başka bir bölümde de sevgilinin vefasızlığını ve cevrini konu edinen beyitler toplanmıştır. bir devâsuz derd imiş gam yok durur dermân ana bir ˋaceb vâdî imiş fürkat ki yok pâyân ana hayretî künc-i gamda hem-nişînüm mihnet ü derd ü ˋanâ hüzn enîsüm gussa eglencem celîsümdür belâ ˋaskerî mecmuada sevgilinin fiziksel ve ruhsal özelliklerinin yanı sıra onun bulunduğu mekân da ele alınmıştır. harîm-i kaˋbe-i kûyun yiter penâh bana harâm ola dahi bir gayrı secde-gâh bana ahmed paşa mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bir serây-ı dil-güşâdur kûyun ey hûr-sirişt kim anun yanında bir kasr-ı müsemmendür behişt emrî eserde sevgiliden başka, aşkın bir diğer aktörü olan âşık ve onun aşk uğruna çektiği acılar da konu edilmiştir. Âh itdügüm efendi senden degül şikâyet bir pâre haste gönlüm bulur anunla râhat figânî Âh itdügümce toldı felekler şerâr ile döndüm şol âteşe tağıla rûzgâr ile Âlî Âşığın hâlleri ile kimi uzuvları çeşitli musiki aletleriyle ilişkilendirilmiştir. derd ü gam bezmine kaddüm gibi bir çeng olmaz nâylar nâlelerüm sâzına âheng olmaz bâkî nâylar bil bagladılar bana dem-sâz olmaga nâleme bezm-i belâlarda hem-âgâz olmaga sun„î bir başka bölümde âşığın bulunduğu mekân, çoğunlukla sevgilinin yokluğunda onun kaderine ve çektiği sıkıntılara eşlik eden bir hüzünler evi olarak karşımıza çıkarken kimi zaman da sevgilinin teşrifiyle bayram yerine dönmüş bir hâlde görünür. mihr-i rûyunla münevver kıldun ey meh hânemüz rûşen olmışdur felekde gün gibi kâşânemüz kâbilî nûr ile toldı külbe-i ahzân geçen gice bizi müşerref eyledi cânân geçen gice necâtî sevgili ve âşık dışında rakibe de eserde yer verilmiştir. onun sevgiliyle olan ilişkilerine ve âşığa eziyetlerine dair beyitler de ayrı bir bölümde toplanmıştır. görmedüm bir mâh-rû ˋâlemde ben agyârsuz gül-şen içre nitekim bir gül açılmaz hârsuz muhibbî yâr cevri bir yana agyâr cevri bir yana gel gidelüm ey gönül sen bir yana ben bir yana necâtî dirîgâ bezm-i agyâra düşüp hûr u hakîr olduk bizi kurtar İlâhî kâfiristâna esîr olduk nâmî Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer kâbilî‟nin eserinde ele aldığı unsurların listesi diğer mecmualarla benzerlik gösterir. ankara Üniversitesi dtcf kütüphanesi mÖ i. koleksiyonu numarada bulunan xvii. yüzyılda tertip edilmiş şiir mecmuasında “fasl-ı bahâr, fasl-ı zülf, fasl- ı hat, fasl-ı bâde vü sâkî, fasl-ı sîne vü dâğ, fasl-ı eşk, fasl-ı hançer bâ- miyân, fasl-ı tîr, fasl-ı gerdân, fasl-ı zenehdân, fasl-ı dendân, fasl-ı ruh, fasl-ı âh u nâle, fasl-ı müje vü gamze, fasl-ı leb, fasl-ı hâl, fasl-ı ebrû, fasl-ı çeşm, fasl-ı rakîb, fasl-ı mezâmîn” başlıkları altında sevgilinin güzellik unsurları, âşığın ve rakibin aşk hâlleri ile bahar tasvirleri üzerine yazılmış seçme şiir ya da beyitler takdim edilir (bkz. aydemir , - ). xviii. yüzyıl şairi lâzikîzâde feyzullah nâfiz‟in letâifü’l-hayâl adlı mecmuasında da “zülf, çeşm, dehân, gabgab, arak, sîne, dendân, zekan” gibi sevgilinin güzellik unsurları, “cevr ü cefâ, istignâ, visâl” gibi aşk hâlleri, “gül-bülbül, şem-pervâne” mazmunları, ilkbahar ve sonbahar betimlemeleri ile felekten şikâyet gibi konularla ilgili örnek beyitlerin yer aldığı görülür (bkz. demir , ). kâbilî‟nin eserinde olduğu gibi bu mecmualarda da sevgilinin güzellik unsurlarına ilaveten âşık, rakip ve bunların aşk hâlleri ile aşkın bizatihi kendisi üzerinde durulmuş, aşk ile ilişkili çeşitli mazmunlara ve mevsim tasvirlerine yer verilmiştir. yine bu eserlerde de sevgilinin tüm güzellik unsurları işlenmemiş ve ele alınan unsurların sıralamasında anatomik yapıya sıkı sıkıya bağlı kalınmamıştır. bütün bu farklılıkların her üç mecmuada da ortaklık göstermesi bu tür mecmuaların kendi içerisinde tutarlı bir yönteminin olduğunu düşündürmektedir. yukarıda sayılan yöntem farklılıkları, mecmuaları bu konuda orijinal bir konuma yerleştirmiştir. ancak asıl önemli farklılık mecmualardaki sevgili algısındadır. diğer eserler sevgiliyi sadece fizikî güzellikleriyle ele alıp onu bir put gibi görürken mecmualardaki sevgili anlayışında bu puta nazıyla, işvesiyle, nezaketiyle ve âşığa cevr ü cefasıyla insanî bir ruh üflenmiş gibidir. sunulan verilerin ışığında sevgilinin güzellik unsurlarını konu edinen mecmua tertip etme geleneğinin, temelde yukarıda bahsedilen eserlerden esinlenmekle birlikte ele alınan unsurları genişletmek suretiyle kendi yöntemini oluşturduğu söylenebilir. bu gelenek içerisinde kâbilî‟nin sultân-ı hûbâna münâsib eşˋâr adlı mecmuası, yazıldığı dönem itibariyle belirleyici bir yere sahiptir. divan şiiri dünyasında gelenekselleşen sevgilinin güzellik unsurları ile sevgili-âşık-rakip algılaması, günümüzde anlaşılmaya çalışılan bir husustur. bu çalışmada üzerinde durulan eserler, bu geleneği üreten şairin ya da geleneğin parçası olan okuyucunun söz mehmet gÜrbÜz turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer konusu hususları nasıl algıladığı konusunda fikir verecek mahiyettedir. bu özellikleriyle de estetik algılayış noktasında kültürel bağlarımızı kopardığımız uzak bir geçmişi anlamaya çalışan günümüz okuyucusu için yol gösterici olacak niteliktedirler. kaynakÇa ali canib ( ). "edebiyat tedkiklerinde mecmuaların rolü", hayat, c. , s. , teşrinievvel, s. - , ankara milli kütüphane, sa . akÜn, Ömer faruk ( ). “divan edebiyatı”, tdv İslâm ansiklopedisi, c. ix, İstanbul: türkiye diyanet vakfı yayınları, s. - . aksoyak, İ. hakkı ( a). “anadolu sahasında İlk bahr-ı tavîl ahmed paşa‟nın mıdır?”, turkish studies, vol. / fall, s. - ; http://www.turkishstudies.net/dergi/cilt /sayi /sayi pdf/ .pdf, (et: . . ). aksoyak, İ. hakkı ( b). “manastırlı celâl‟in hüsn-i yûsuf adlı eseri”, (ed. ayşenur külahlıoğlu İslam, süer eker), dil ve edebiyat yazıları – mustafa İsen’e armağan, ankara, s. - . atay, hakan ( ). heves-nâme’de aşk oyunu: tâcî-zâde cafer Çelebi’nin Özgünlük İdeali, bilkent Üniversitesi ekonomi ve sosyal bilimler enstitüsü, basılmamış yüksek lisans tezi, ankara. aydemİr, yaşar ( ). “Şiir mecmuaları ve metin teşkilinde mecmuaların rolü”, bilig, s. , güz, s. - . demİr, hiclal ( ). “xviii. yüzyıl klasik türk edebiyatı Şairlerinden lâzikî-zâde feyzullah nâfiz ve dîvân‟ı Üzerine”, hacettepe Üniversitesi edebiyat fakültesi dergisi, aralık, c. , s. , s. - . erÜnsal, İsmail ( ). “muˋîdî‟nin miftâhu‟t-teşbîh‟i” osmanlı araştırmaları, vii-viii, İstanbul, s. - . kâbilî (tsz). müntahabât-ı eşˋâr: sultân-ı hûbâna münâsib eşˋâr, i, millet kütüphanesi, ae manzum . kâbilî (tsz). müntahabât-ı eşˋâr: sultân-ı hûbâna münâsib eşˋâr, ii, millet kütüphanesi, ae manzum . http://www.turkishstudies.net/dergi/cilt /sayi /sayi % pdf/ .pdf http://www.turkishstudies.net/dergi/cilt /sayi /sayi % pdf/ .pdf http://www.turkishstudies.net/dergi/cilt /sayi /sayi % pdf/ .pdf Şiir semasının yegâne yıldızı; güzeller sultanı turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer kâfzâde fâizî (tsz). zübdetü’l-eşˋâr, ankara milli kütüphane, yz a , vr. b. kiliÇ, filiz ( ). meşâˋrü’ş-Şuˋarâ - İnceleme-metin, İstanbul: İstanbul araştırmaları enstitüsü. kÖksal, fatih ( ). sana benzer güzel olmaz (divan Şiirinde nazire), ankara: akçağ yay. kurnaz, cemal ( ). osmanlı Şair okulu, ankara: birleşik dağıtım kitabevi. kut, günay ( ). “mecmualar”, türk dili ve edebiyatı ansiklopedisi, vi: - , İstanbul: dergâh yayınları. levent, agâh sırrı ( ). türk edebiyatı tarihi, ankara: ttk basımevi. mehmed süreyya ( ). sicill-i osmânî, haz.: nuri akbayar, İstanbul: tarih vakfı yurt yay, c. , s. . riyâzî (tsz). riyâzü'ş-Şuˋarâ, ankara milli kütüphane, hk , vr. b. sungurhan eyduran, aysun ( ), kınalızâde hasan Çelebi – tezkiretü’ş-Şuˋarâ, ankara: kültür bak. e- kitap (metin b); http://ekitap.kulturturizm.gov.tr/genel/dg.ashx?dil= & belgeanah= &dosyaisim=tsmetinb.pdf, (et: . . ). Şafak, yakup ( ). “sürûrî‟nin bahrü‟l-maˋârif‟i ve bu eserdeki teşbih ve mecaz unsurları”, türkiyat araştırmaları dergisi, s. , s. - . Şerafeddîn râmî ( ). enîsü’l-uşşâk - klasik doğu edebiyatlarında sevgiliyle İlgili mazmunlar, Çev.: turgut karabey, numan külekçi, habib İdrisî, ankara: ecdad yay. tanyildiz, ahmet ( ). “sevgilide güzellik unsuru olarak saç”, turkish studies, vol. / winter, s. - ; http://turkishstudies.net/sayilar/sayi / tany%c %b ld% c %b zahmet.pdf, (et: . . ). tuman, mehmet nail ( ). tuhfe-i nâilî: divan Şairlerinin muhtasar biyografileri, haz.: cemal kurnaz-mustafa tatcı, ankara, c. , s. , md. . http://ekitap.kulturturizm.gov.tr/genel/dg.ashx?dil= &% belgeanah= &dosyaisim=tsmetinb.pdf http://ekitap.kulturturizm.gov.tr/genel/dg.ashx?dil= &% belgeanah= &dosyaisim=tsmetinb.pdf http://turkishstudies.net/sayilar/sayi / tany%c %b ld%c %b zahmet.pdf http://turkishstudies.net/sayilar/sayi / tany%c %b ld%c %b zahmet.pdf african american dance - philosophy, aesthetics, and ‘beauty’ thomas f. defrantz abstract: this essay considers the recuperation of ‘‘beauty’’ as a productive critical strategy in discussions of african american dance. i argue that black performance in general, and african american concert dance in particular, seeks to create aesthetic sites that allow black americans to participate in discourses of recognition and appreciation to include concepts of ‘‘beauty.’’ in this, i suggest that ‘‘beauty’’ may indeed produce social change for its attendant audiences. i also propose that interrogating the no- tion of ‘‘beauty’’ may allow for social change among audiences that include dance theorists and philosophers. through a case- study consideration of work by three african american chore- ographers, donald byrd (b. ), ulysses dove ( – ), and abdel salaam (b. ), i ultimately hope to suggest critical possibilities aligning dance performance with particular aesthetic theory relevant to its documentation and interpretation. a metaphysics, ontology, epistemology, or aesthetics is necessarily distorted by communicative practices which invariably include inherited and privileged structures, forms, assumptions, and codes that remain unstated. the subject, on such accounts, may be considered problematic because the subject may inappropriately present its ideas as ones that surmount the limitations of what it is to be a subject – contextually bounded. aesthetics in dance, and especially the terms of ‘beauty’ as they might relate to african american artistry, remain extremely difficult to discuss. how can aesthetic theory be engaged in relation to african american dance practice? what sorts of aesthetic imperatives surround african american dance and how does black performance make sense of these imperatives? who names the quality of performance, or who determines that a performance may be accu- rately recognized as ‘black’? more than this, how can african american dance participate on its own terms in a discourse of ‘beauty’? this essay offers portions of my current research project to consider the recuperation of ‘beauty’ as a productive critical strategy in discussions of african american dance. i argue that black performance in general, and african american concert dance in particular, seek to create aesthetic sites that allow black americans to participate in discourses of rec- ognition and appreciation to include concepts of ‘beauty’. in this, i suggest that ‘beauty’ may indeed produce social change for its attendant audiences. i also propose that interrogating the notion of ‘beauty’ may allow for social change among audiences that include dance theorists and philosophers. through a case-study consideration of work by three african american choreographers, donald byrd (b. ), ulysses dove ( – ), and abdel salaam (b. ), i ultimately hope to suggest critical possibilities aligning dance performance with particular aesthetic theory relevant to its documentation and interpretation. . ‘beauty’ in philosophy, dance, and african american studies i mean for the essay epigraph by philosopher leonard harris to suggest that ‘aesthetics’ and ‘beauty’ num- ber among the seemingly limitless subjects of both dance and philosophy. aesthetics, as a field of in- quiry, has not served dance, as a practice, well. very little productive aesthetic theory related to dance has been published in the last century, and the literature related to modern or contemporary dance remains exceedingly thin. in many ways, the subject of dance within the context of aesthetic theory – especially contemporary western concert dance – seems to ex- ceed the limits of communication for those trained in that field. recently, american philosophers have been willing to explore ‘beauty’ as an aesthetic action useful to the topoi ( ) : – � springer doi . /s - - - process of human recognition. notably, in on beauty and being just, professor of aesthetics elaine scarry constructs an argument for ‘beauty’ as a sensate cognition that can lead toward social justice. for scarry, ‘beauty’ contains sacred, unprecedented, and life-saving features that incite deliberation about the nature of truth and fairness. in recognizing and appreciating ‘beauty’, people experience its pressure toward distribution, and seek to both protect and reproduce (or create) its effects. in addition, as ‘beauty’ brings copies of itself into being, its observers undergo a ‘‘radical decentering’’ that moves them toward ethical fairness; and ‘‘people seem to wish there to be beauty even when their own self-interest is not served by it.’’ in this analysis, ‘beauty’ may achieve more than its presence suggests, as human responses to ‘beauty’ may include social action. scarry does not lay out the terms of ‘beauty’ she considers except by example of things seen and then felt; she seems to assume its recognition to be self- evident. her referents – a boy, a palm tree, a flower, a bird, the sky, among others – align her theory to romanticist assumptions about ‘beauty’ as it might be ever-present in nature. she offers little criteria for the recognition of ‘beauty’, although she does men- tion, in passing, a quality of symmetry as an ‘‘important element’’ in its assessment. because she writes of the largest concept of ‘beauty’ as a natural presence, she seems to be unconcerned with any spe- cific aesthetic qualities that mark its discovery. for scarry, the pressure toward distribution performed by ‘beauty’ is something already done by nature; a task that may be imitated by people (creative artists), but need not be ‘‘because it does not depend on human beings to bring it about.’’ in other words, ‘beauty’ will persist whether humanists are willing to explore its qualities or not. scarry is only one of several contemporary american philosophers who write about ‘beauty’. her universalist ethos, however, strikes familiar po- ses of exclusion for many contemporary stage cho- reographies, which are not concerned with the persistence of lightness or grace, as well as the physiognomic attributes of african americans, which have rarely been considered ‘beautiful’ by the larger american public. my project seeks to explore the recognition points of ‘beauty’ that african american audiences attend to in dance performance in order to expand on the notion of what may be perceived as ‘beauty’, as well as the logic that determines who may name that quality. on the whole, contemporary dance studies has ignored the function of ‘beauty’ as a potent aesthetic paradigm. we can easily understand why: the concept seems at once extremely unstable – what are the terms for recognizing ‘beauty’? – and monolithic, without significant nuance. more than this, ‘beauty’s’ philo- sophical lineage has ignored dance, all the while positing universal values from which african ameri- can identity and subjectivity have also been excluded. yet many of the possibilities scarry, among others, raises relate easily to african american concert dance practice. here, dance performance may refer to the spiritual (sacred) and spontaneous (unprecedented) choreographies that have sustained generations of african american dancers in the context of harsh everyday racialized interactions (its life-saving fea- ture). among dance critics and historians, the quality and content of african american concert dance has generated sustained debate about its choreographic nature (can it be recognizably ‘beautiful’ in and of it itself?) and the access of black americans to advanced training in white-operated academies and schools (how can it press toward distribution? who has access to it?). while i do not mean to imply that african american concert dance embodies ‘beauty’ in and of itself, scarry’s assertions will become important in later discussions of particular dances. . a ‘beautiful’ duet for ethnophilosophy and feminist aesthetics amid continuous overarching questions around what the terms of ‘beauty’ may be and who may name them, i contend that ‘beauty’ might be recuperated effectively as a critical paradigm when deployed within a particular, culturally explicit frame of per- formance analysis. my study of ‘black beauty’ seeks to invigorate the analysis of how african american audiences experi- ence and respond to aspects of concert dance in contexts that may be termed ‘black’. my interest centers on how ‘beauty’ is constructed by the body in motion, or more precisely, in the space between artist and audience that the concert stage inevitably creates. african american philosophy, a branch of ethno- philosophy, offers a grounding context for aesthetics thomas f. defrantzthomas f. defrantz relevant to african american dance. in phi- losopher cornel west argued that this then-emergent literature sought to ‘‘make theoretically explicit what is implicit in afro-american history to describe and demystify the cultural and social practices in this history and offer certain solutions to urgent problems besetting afro-americans.’’ west’s materialist call for philosophy as action informs african american dance practice: these choreographies emerge to offer simultaneous solutions to adverse minoritarian con- ditions, as well as fulfillment of aesthetic imperatives embedded within their recognition as ‘black’. african american philosophers have long under- scored the creative and world-making view of phi- losophy as a practice, as well as the political importance of the documentation of a recognizable constellation of cultural processes. as with dance, the professionalization of philosophy for african amer- icans is fairly recent. among its earliest proponents, author and harlem renaissance critic alain leroy locke earned his doctoral degree in philosophy from harvard university in . locke’s interest in the arts, represented by his editorship of seminal docu- ments related to african american participation in dance, music, visual arts, and letters, set a twentieth- century standard for an alignment of african amer- ican philosophy and aesthetics. in large part, locke’s efforts signaled the arrival of modern african amer- ican subjectivity in the european and european american imagination, as his critical work established recognizable boundaries for a consideration of long- standing art practices. locke’s ‘‘ethnophilosophical’’ method documented the existence of african american artists as well as the persistence of african american cultural practices that flourished, unexplored by most critics, in segre- gated contexts. his studies assumed a black ontology, represented in artistic creations, that his focused critical attention brought to light for all to see. for locke, the act of documenting presence in the arts satisfied a need to place african american creative practices within a larger context of recognized euro- pean and euro-american artistry. clearly, ‘‘ethnophilosophical’’ approaches are hybrid and politically motivated. philosopher anthony appiah asserts that there may be no ‘native’ african tradition in philosophy, since philosophy as a practice has been created by the west. still, philoso- phy becomes an inevitable partner in a project to ground aesthetic theory in performance research, if only because it contains what appiah terms ‘‘the highest-status label of western humanism.’’ the current project to articulate a notion of ‘black beauty’ in concert dance bears similar weight; ‘beauty’ is, of course, among the highest-status labels of gesture as thought, action, and spiritual wholeness. in a context that considers america’s continuously fraught racial asymmetries, any maneuver to align african ameri- can corporeal practices and aesthetics with narratives of ‘beauty’ proposes a strategic recuperation of some political import. here i follow philosopher lucius outlaw’s sug- gestion of african american philosophy as a ‘‘gath- ering notion’’ around which to create a possibility of moving toward a useful philosophy of black perfor- mance. outlaw reminds us that all philosophy is created according to an agenda of arranging and naming, and emerges as ‘‘a matter of historical, cul- tural, social, and political circumstance’’ involving the people who produce it. this may seem self-evident: what reason might there be to invent philosophy other than to present ideologies of a particular sub- ject-location? however, the implications of consider- ing philosophy as a response to material need are broad. in terms of dance, an african american phi- losophy of aesthetics may allow us to recognize and articulate qualities of performance in a way that eurocentric aesthetics cannot. but we must also resist a rush to rewrite aesthetics in order to understand dance. in a discussion of african cultural practices and the circumstances surrounding their narration by contemporary philosophers, outlaw cautions: ‘‘the practices named do not require this arranging and naming as security for their meaningfulness or integrity, nor for their validity.’’ for outlaw, phi- losophy may make sense of particular practices for the purposes of philosophy, but this process of anal- ysis emerges in response to practices ‘‘already done.’’ in similar terms, african american dance perfor- mance may ‘‘gather’’ around particular aesthetic principles, but it will never conform to those guide- lines as if only to satisfy their delineation. similarly, feminist aesthetics provides a counter- balance to the prevalent kantian model of beauty as a form of jouissance experienced by an individuated [masculine] beholder, typically as he gazes on a static object, like a flower. cultural theorists including joanne waugh and rita felski have argued that african american danceafrican american dance feminist aesthetics might be an approach to aesthetic theory more than any single totalizing formulation. felski points out that while feminist criticism ‘‘does not need an (autonomous) aesthetic, it cannot afford to ignore the realm of the aesthetic, because it is nec- essarily implicated within and influenced by its insti- tutional and discursive logics.’’ surely this is true for an africanist dance criticism as well; for its artists, audiences, and critics are aware of competing and contradictory concert dance idioms whose aesthetic sensibilities are not easily reconciled. felski clarifies her motives thus: ‘‘from romanticism to modernism and postmodernism, the figure of the artist has become closely identified with an ideal of transgressive masculinity, while women have been seen as, at best, capable of reproduction and imitation, but not of creative innovation.’’ in this, she might make refer- ence to any african american modern or postmodern dance artist, whose works are almost inevitably teth- ered to the european-derived parentage of balan- chine, cunningham, graham, or wigman. finally, felski argues that ‘‘women’s art has been typically read by critics as an expression of the limits of their sex; the transcendent and universal qualities ascribed to great art have remained almost by definition beyond their reach.’’ here echo generations of dance critics and aesthetes who discuss african american dance as merely an expression of the limits of a rec- ognizable black identity. so long as african ameri- cans dance ‘black’, these critics report, they will only be able to express that limited experience without access to the realms of universal ‘beauty’ and ‘truth’. but what if ‘beauty’ need not be universal, or even visible, to be potent? feminist aesthetics coupled with ethnophilosophy offers a resistant platform to con- sider the possibility, as well as the means, to move beyond the realm of the visual as the dominant sig- nifier of aesthetic meaning. for example, laura mulvey famously engaged this resistant critique of a prevalent visual pleasure offered by film. her exposure of a recurrent masculinist gaze constructed by mainstream hollywood films indicted the tyranny of the visual in the construction of pleasure and ‘beauty’. as feminist philosopher hilde hein notes, aesthetic philosophy since plato has referred to vision as ‘‘the noblest and most theoretical of the senses’’ in the west. however, an africanist aesthetic enact- ment of ‘beauty’, as i intend to explore it, refers to the visual as only an aspect of the sensorial. to move beyond ‘beauty’ as something visually apprehended, toward ‘beauty’ as a performed gesture felt by a witnessing audience, we must be willing to resist the primacy of sight as truth, and allow for the possibility of an aesthetic sensibility concerned with spirit. thus, my thesis emerges here, at the shared edges of ‘‘ethnophilosophy’’ and feminist aesthetics. to recognize ‘black beauty’ in motion, we engage awareness of social and political circumstance as well as the perception of fullness of gestural execution and the manifestation of spirit. i shall turn now to con- sider possibilities of black performance, answered in part by case study considerations of particular cho- reographies. . ‘beauty’s’ bits: black performance, narrative, and movement lexicons black performance allows us to imagine possibilities for social movement, social particularity, social flexibility, and social change. its evidentiary markers – ‘black’ and ‘performance’ – are each contingent manifestations, deployed according to particular contexts. as a social category, ‘black’ becomes implicitly bound up with ‘white’, ‘asian’, ‘latino’, ‘aboriginal’, and other cor- poreal locations; ‘black’ does not exist without a pre- sumption of other identities. in this, ‘black’ implies particular social referents as well as social movements through those referents towards boundaries supplied by other social categories. the performance of black- ness, then, may refer constantly to absent, discarded, and elided performances which form an offstage background to the social category of ‘black’. black performance emerges as an inflection of social identity in motion, with intimations of movement toward and away from contingent social categories. elements of performance that may be consistently recognized as ‘black’ allow us to consider social par- ticularity. within shifting social boundaries, black performance carries corporeal artifacts – gestures, rhythms, soundings, rhetorics, aesthetic logics – that distinguish it among itself. ‘black’ may describe a contingent social location, but its emergence in per- formance is tied to the perception of particular ges- tures. these gestures form the corpus of a performance ideology that holds significant import in the realm of american concert dance, and comprises the distinctive features of african american concert dance. thomas f. defrantzthomas f. defrantz and yet, social flexibility is embedded in black performance by virtue of its citational – its ‘signifyin’ – ethos. black performance prizes referential logics and spontaneity as foundational creative approaches. spontaneity may be borne out as rhythmic emphasis or unexpected citation in any idiom of black perfor- mance, including music, oratory, social dance, and concert dance. this flexibility of source material and its interpretation also underscore the contingency of ‘black’ as a marker of social location: improvisation and spontaneity confirm unexpected possibility as a hallmark of black performance. finally, black per- formance can herald social change in the moment of its emergence. because the visible evidence of ‘black’ highlights other social identities, and its performance prizes spontaneity and flexibility while referring to a particular black ground, its presence achieves a simultaneous stabilizing and distending effect. black performance can enable social change by confirming its transformative possibility. in this final feature, we find the possibilities of ‘beauty’ as a productive aspect of performance. african american dance can cho- reograph gestures of ‘beauty’ recognizable to african american audiences, a possibility denied in almost any other modern american location. here, concert dance may predict social change through the staging of ‘beauty’ as an action. to offer a case study of performance that marks out social flexibility and social change through the use of particular movement lexicons, i turn to the work of donald byrd. for byrd, ‘beauty’ often comes to be tied to the triumph of physical tech- nique, or excellence in form. form is tied to finish, with jagged edges smoothed into a seamless perfor- mance persona engaged by the dancers. the ruptures of byrd’s rhythmic phrasing make clear principles of percussive attack or complex meter, but without breaking an overall flow of movements performed to their physical ends. in pushing his dancers to work at the ends of physical possibilities, he forces them to respond in the physical crucible of the spirit. this, in turn, extracts a ‘beauty’ of dancing in the spirit by virtue of the force of physical challenges posed to the dancers. byrd stages social movement within dance idioms, born of the tension between the exe- cution of balletic movements with a low-to-the- ground, weighted stance. byrd’s choreographic project explores the expres- sive limits of classical ballet technique sutured to the weightiness of modern dance. his work tends to be highly kinetic – almost excessively so – in an effort to align compositional rigor with a patently discur- sive physicality. highly literate in terms of dance compositions, his works always reference other dances, and he enjoys a choreographic game in which he challenges his audiences to recognize trace elements of other choreographies as they are played out in his own constructions. in dance at the gym ( ) for instance, byrd makes structural reference to jerome robbins’ choreography from west side story, wrung through an africanist aesthetic wringer. the work for eight dancers – four men and four women – describes competitions and flirtations among a group of urbanites in a workout session of sorts, set in an abstraction of a commercial gym. in one sequence, we are invited to view the percussive attack of the dancer as she repeatedly pierces the space above her head with her pointed foot; the antiphonal phrasing that constructs gestural responses to various movement calls; the complex rhythm and apart-playing of a group of women that challenge us to repeatedly choose a focal point within the proscenium frame. these choreographic structures signal the work’s convergence with africanist aesthetic features. the dancer hits her foot against the space above her head with an unanticipated, tangible force. the attack of her kicking gestures conveys a temporal rift in the basic rhythmic pulse of the dance and its musical score. the unexpected bursts of percussive attack serve as a reminder of powerful, submerged forces that propel the more obvious, visible rhythmic phrasing and aural musical gestures. they allow for the recognition of spirit as they herald the extension of rhythmic possibility in the dance. byrd’s choreography reveals itself to be ‘black’ through its citations, call and response, complex rhythmicity; it conducts ‘beauty’ through the cor- poreal luster that its virtuosity creates. byrd encourages an intense visual ‘finish’ from his dancers that becomes as important to his work as the com- positional strategies he employs. as if to coax every ounce of tension from their taut performances, the movements are phrased to emphasize an unim- peachable mastery of physical technique in terms of, at least, flow, depth of spatial field, and rhythmic intensity. this performed ‘finish’ contributes to a quality of ‘beauty’ aligned to an aesthetic of the african american danceafrican american dance cool; byrd’s dancers perform super-hero styled feats without, it seems, breaking a sweat. in this way, they construct ‘beauty’ as action that predicts social change through the synthesis of dance aesthetics. here, ballet is sutured to modern dance via afri- canist aesthetic principles to charge the stage with vistas of ‘beautiful’ virtuosity and luster. where the brightness and sheen of byrd’s chore- ography proposes ‘beauty’ as a visible effect of dance motion and a suturing of dance movement lexicons, other choreographers focus on the force of unseen social narratives to produce motions of ‘beauty’. in an irony not without consequence, nearly all of the markers of performance that allow its recognition as ‘black’ are nonmaterial. virtual forces propel black performance, and these nonmaterial aspects from its substance. they include the gestures, the tonalities, the guttural wails, the rhythmic complexities, the deployment of allusions, the tempi and forces of action that shape performance. unlike the physical technique of, say, martha graham modern dance, these aspects of black performance have no codified system of production; no physical training that per- petually produces their effects. to discuss the nonmaterial, we find the usefulness of ‘spirit’ as an animating feature of africanist per- formance. ‘spirit’ might be similar to the sacred aspect of ‘beauty’ that scarry mentions, in that its nonma- terial manifestations are bound up with ‘faith’ and legacies of ‘knowledge’. in the context of black per- formance, ‘spirit’ refers to the contingent presences of immaterial, animating, vital forces that allow human beings to recognize incorporeal actions. the spirit ‘flashes’ in africanist performance to momentarily confirm incorporeal action enabled by the perfor- mance, and not bounded by the performer’s body. in the ‘flash of the spirit’ we find what african art his- torian robert farris thompson has described as the motivation of successful africanist performance. to enable the flash of the spirit, the dancer must be willing to become the thing that is being danced or being summoned. other aesthetic theorists, including choreographer and author delores cayou, have termed ‘‘functionalism’’ – or a willingness to become the thing that is danced – as an aspect of excellence in africanist performance. this aspect teams the artistic ability to become the dance with the gathered audience’s ability to perceive the ‘spirit’ animated by the dance, and to honor and protect its arrival. in this group action of honoring and protecting, the mani- festation of ‘spirit’ is again likened to the sacred components of ‘beauty’ mentioned by scarry. clearly, ‘spirit’ needn’t be tied to a particular religious doc- trine. it emerges in the fullness of gesture performed with vitality and clarity for the purpose of group cognition – at times, for the performance of ‘beauty’. here, i turn to the work of choreographer ulysses dove. dove’s choreography is marked by its relentless speed, violent force, and daring eroticism. he treats the dancer as a weapon of sorts, out to slay the demons of torpor. his movement palate is impossibly dense, requiring a precision of execution as well as an inevitable extension of the technical capability of its dancers. many of his works portray an unlikely community of people who seem to know each other well; they describe violence as an inevitable family trait that will result from their interaction. the world of these works is up in arms; fights emerge from multiple simmering hostilities, and an anger palpably born of social and sexual dysfunction forces the people of these works through uncomfortable com- promises in terms of movement. his work episodes ( ) described a harsh land- scape of men and women who rush toward each other as if to connect emotionally, but are inevitably repelled by the very force of their [e]motion. clad in chic, form-fitting black, the dancers are pinned, rather than revealed, by shafts of blinding white light focused as a diagonal crossroads on the stage. the overall mood is unrelentingly tense, in no small part due to the extreme physical demands of dove’s cho- reography. when slow-motion phrases emerge, they offer little release from the overall drive and fervor of the staging. episodes presents a landscape of urgency and danger. within this misanthropic space, audi- ences may recognize actions as an expressive response to the random racism of everyday life for many african americans. in recreating violence and intense physical challenge as the lingua franca of his work, dove stages african american survival and perse- verance as aesthetic action. the dance offers ‘spirit’ in its existence and repeatability; it proposes ‘beauty’ as an ability to survive. episodes, like other of dove’s works, depicts a world of narrative relationships without beginning or ending; of actions answered by movement conse- quences that lead to other movement choices without reference to theatrical mise en scène. many of dove’s thomas f. defrantzthomas f. defrantz works take place in oblique settings that suggest abstractions of physical locations without details of particularity. for example, episodes is set at a phys- ical ‘‘crossroads’’ designated by the lighting design; the dancers relate to each other as people, with par- ticular histories, somehow trapped within this sceno- graphic limbo. the dancers here persist, as if to underscore a truth of african american corporeality that endures through adverse social circumstances. the stories of the dancers and their relationship are viewed through an aesthetic lens that values the arrival of ‘spirit’ in certain movement sequences – an unexpected drop to the floor; a series of turns per- formed on the knees; an unanticipated foot-stomping sequence that echoes ecstatic religious dancing. dove aligns ‘beauty’ with the survival of black subjectivity in these stories of relationships – violent, harsh, nuanced and erotic – that confirm a persistence of black corporeality. while explorations of individual subjectivity offer a valuable platform for considerations of black beauty, particular dances and dance practices also mark black performance in diaspora. as practice and commodity, black performance creates vibrant economies of national and global production and dispersal. in terms of african american dance, this process began in the nineteenth century with the cakewalk, a transformed slave festival dance that became first a national, and then international fad at the beginning of the twentieth century. black social dance idioms, from the cakewalk to hip hop, have held currency in all corners of the world, where they are often per- formed by dancers with no recognizable african ancestry. this tendency toward distribution of black performance underlines ‘diaspora’ as a possibility available to these aesthetic constellations. a geneal- ogy of performance in diaspora echoes and recasts the standard understanding of ‘diaspora’ as the move- ment of bodies across geography. while popular african american social dances have emerged at regular historical intervals to be dispersed into global contexts, in the wake of the s civil rights movement african americans have embraced neo-african choreographies. these dances reference ‘beauty’ as a reclaiming of creative gestural expression derived from an (imaginary) ancestral homeland. neo- african dance forms, also highly popular among african, latino, and european americans, offer diasporic opportunities for holistic corporeal mem- ory. ancestral ‘beauty’ is protected by these dances, in their recovery by african americans, and in their frequent staging in touring concert dance festivals such as the annual danceafrica series. here, abdel salaam’s choreography offers insight. salaam constructs ‘beauty’ as an inevitable function of civil rights activism that laid bare afri- canist aesthetics in diaspora. neo-african dance forms gained currency in the united states as a function of dispersed black arts movement ideolo- gies. salaam’s interest in these choreographies grew as he found dance to be a ‘‘tool of empowerment, a tool of stimulation’’ for his core african american audience. he propels his interest in dance as black studies through teaching and choreography, with an intention to underscore that dance may offer simul- taneous political action and art. he created his company to encourage a particular mode of specta- torship, one that resonates with a neo-african diasporic ethic. in ancestral earths ( ) salaam collaborated with several native american dancers to explore intertwined diasporic legacies. the work stages afri- can american dancers and musicians, clad in beaded neo-african costume, in tandem with native ameri- can dancers and musicians, dressed in feathered cer- emonial garb. in the theater space, the visual synergy of extravagant costume establishes an obvious grounding of mythic ‘beauty’ in motion. the move- ment vocabulary of the work confirms distinctions in percussive approach. where salaam’s choreography highlights complex arrangements of body-part isola- tions in densely-layered patterns, the native ameri- can choreography teases nuance from repetition of steady, full-bodied pulsations. the work offers ever shorter alternations of separate native and african american dance ideas, to culminate in a shared improvisational space entered by dancers representing each tradition. salaam’s work often highlights ‘diaspora’ as source of ‘beauty’ in the form of remembered neo- african choreographies. he also stages gender according to a holistic africanist worldview that assumes the presence of distinctive ‘male’ and ‘female’ energies in every human being. in his work, grand themes of communal interest, including judgement, rebirth, and regeneration, are to be considered as sources of primal energy to be recycled through the art of dance. particular dances of west african american danceafrican american dance african origin, also restructured for the stage, pro- vide the foundational movement lexicon for many of his works. while these dances are not practised by large numbers of african american audiences, they are recognized as part of a diasporic movement legacy that references black group identity through performance. movement lexicons, interpersonal narratives, and diasporic dances transferred to the concert stage provide three prisms through which ‘beauty’ may be reflected. but ‘beauty’ must be recognized as such in order to fulfill its potential. in terms of dance, the process that allows audiences to recognize ‘beauty’ remains insufficiently theorized. the performing arts function within increasingly impoverished systems of thought dedicated to analysis or interpretation. we need only consider how alvin ailey’s first-generation modern work revelations ( ) stands for ‘black dance’ in an unequivocal way that forecloses broad black audience interest in, say, the work of post- modern african american choreographer bebe mill- er. ‘beauty’ may be enacted in choreography constructed by both ailey and miller, but it must be recognized in context in order to thrive. the recog- nition of ‘beauty’, especially in terms of concert dance, is in no way automatically achieved. concert dance is not symmetrically available to all african americans who might attend it, notwith- standing material expense or aesthetic education. even if all those who wanted to attend concert dance performances could do so, this work demands a grounding in the aesthetic logic of stage performance that must be undertaken by audiences. ‘black beauty’, as i discuss it here, is performed within a frame of the concert stage proscenium. unfortunately, a useful grounding in the aesthetic experience of dance attendance escapes the growing african american working class and lower-middle class populace. ‘beauty’ – in any definition – cannot flourish without representation. it has to be reflected, pur- sued, and circulated to be engaged; it has to be assembled in its component parts to fulfill itself, it must be remembered to construct its effects. ‘beauty’, like ‘blackness’, offers a contingent experience that grows in volume as critical theory is brought to bear on its contents. i do not argue here for the contrivance of strict critical formulae as the basis for aesthetic awareness or the recognition of ‘beauty’. when ‘beauty’ emerges in african american choreographies of the concert stage, its presence and appeal break from any sur- rounding structures, including the hybrid euro- american modern dance legacies that its choreogra- phers may engage. this approach to reconsider the terms of ‘beauty’ offers a way to consider african american subjectivity within dance that might allow it to flourish on its own terms. ‘beauty’ need not be universal to be a potent and important paradigm for group awareness and well-being. ‘black beauty’, defined here as performed movement, might allow philosophy and dance studies to reconsider how var- ious ‘truths’ of movement are contingent upon the analytical frames brought to bear on their contents. not all audiences recognize ‘beauty’ in these works or as it might be performed by african american danc- ers. ‘black beauty’ surely exists in terms of concert dance; its aesthetic principles and contents demand sustained exploration. my hope here is to participate in the creation of a conversation about ‘black beauty’ in concert dance that opens possibilities for sustained discussions of aesthetics. in this, i hope that ‘beauty’ may emerge in this process, and then disappear again, to leave all of us marveling in its wake. notes harris , p. . scarry . scarry , p. . ibid., p. . ibid., p. . among many studies of racialized history of american dance practice, see especially gottschild ( ), long ( ), perpener ( ), and manning ( ). outlaw ( ) offers an effective overview of theoretical and semantic distinctions between african, african american, and africana philosophy. for the overview-granting purposes of this essay, i will use only ‘african american’ where ‘afro- american’, ‘african’, or ‘africana’ may offer more nuanced implications. west , p. . locke’s ( – ) many publications include negro art: past and present and the negro and his music, both published in ; see leroy ( ). appiah , p. . outlaw , p. . ibid. p. . ibid. felski , p. . thomas f. defrantzthomas f. defrantz ibid. p. . ibid. mulvey . hein , p. . raised in the american black middle class of the s, byrd studied performance aesthetics and dance at tufts and yale universities, the cambridge school of ballet, the london school of contemporary dance, the alvin ailey american dance center, and with mia slavinska. he danced, briefly, with twyla tharp, karole armitage, and gus solomons jr. before he founded his company donald byrd/the group in with a commitment to the idea that ‘‘dance can change and enrich the lives of many people.’’ (byrd, ) highly prolific, he has created over works for his own company and others, including a production of carmina burana for the new york city opera. in byrd dissolved his own company and assumed artistic directorship of the spectrum dance theater of seattle, washington. thompson ( ). thompson’s inventory of ‘‘guiding prin- ciples’’ of africanist performance has been frequently recounted, but bears repeating here. they include dominance of a percussive performance style; multiple and complex rhythmic meter; overlapping call and response in singing; an inner impulse control that retains a rhythmic common denominator; suspended accentuation patterning that allows for cross-rhythms; and the performance of songs and dances of social allusion. cayou , p. . born in columbia, south carolina, the eldest of three children, dove began dance study with carolyn tate while a pre-medical student at howard university. he transferred to the university of wisconsin to study with xenia chlistowa of the kirov ballet, and in graduated from bennington college with a degree in dance. upon moving to new york, dove joined the merce cunningham company and performed with mary anthony, pearl lang, and anna sokolow. in he joined the alvin ailey american dance theater, where he quickly rose to the rank of principal dancer acclaimed for his commanding presence, bright clarity of movement, and truthful dramatic intensity. he turned to choreography in , and began a significant freelance career making dance for the basel ballet, the cullberg ballet, the dutch national ballet, the london festival ballet, american ballet theater, the new york city ballet, and the groupe de recherche choreographique de l’opera de paris where he spent three years as assistant director. dove’s death from aids placed him among the most prominent of publicly discussed gay male black dance artists. krasner . heard and mussa . since , danceafrica has offered an annual festival of american dance companies based in traditional and neo- african idioms. the festival continues to be organized by african american founding director chuck davis. born and raised in new york city, salaam trained in modern and neo-african dance as an adult student at lehman college under the guidance of joan miller. he quickly became concerned with patently hybrid constructions of dance idioms. he founded his company, forces of nature, in with a desire to combine martial arts, lester horton—and jose limon-based methods with selected sub-saharan african dance languages to explore the cultural and philosophical foundations of african dance traditions. housed in manhat- tan’s church of saint john the divine, forces of nature performs salaam’s emphatically diverse repertory that includes postmodern offerings as well as many neo-african dance and drumming pieces. the company achieved acclaim in new york and internationally for its recreation of historical, mythical, and epic events through dance theater based in africanist narrative themes. heard and mussa . salaam . on separate occasions, salaam’s collaborators included the silver cloud native american dancers and musicians, and matoaka little eagle with members of the thunderbird american indian dancers. references appiah, anthony: , ‘african-american philosophy?’, in pittman, – . brand, peggy zeglin, and carolyn korsmeyer, (eds): , feminism and tradition in aesthetics. university park, pa: the pennsylvania state university press. byrd, donald: , personal interview with author, seattle, washington ( january). cayou, delores k.: , modern jazz dance, palo alto: mayfield publishing company. defrantz, thomas f. (ed.): , dancing many drums: excavations in african american dance, madison: univer- sity of wisconsin. felski, rita: , ‘why feminism doesn’t need an aesthetic (and why it can’t ignore aesthetics),’ in brand and korsmeyer ( ), pp. – . gottschild, brenda dixon: , digging the africanist pres- ence: dance and other contexts, westport, ct: greenwood publishing. harris, leonard: , ‘the horror of tradition or how to burn babylon and build benin while reading ‘‘a preface to a twenty-volume suicide note’’,’ in pittman ( ), pp. – . heard, marcea. e. and mussa, mansa: , ‘african dance in new york city,’ in defrantz ( ), pp, – . hein, hilde: , ‘the role of feminist aesthetics in femi- nist theory’, brand and korsmeyer, pp. – . krasner, david: , resistance, parody, and double con- sciousness in african american theatre, – , new york: st. martin’s press. locke, alain leroy: , the negro and his music, reprinted, port washington, ny: kennikat press, . also rep- rinted with negro art: past and present, new york: arno press, l . african american danceafrican american dance long, richard: , the black tradition in american dance, new york: rizzoli international publications, inc., lott, tommy l. and john pittman, (eds): , a companion to african-american philosophy, malden, ma: b ackwell publishing ltd. manning, susan: , modern dance, negro dance: race in motion. minneapolis: university of minnesota press. mulvey, laura: , ‘visual pleasure and narrative cinema,’ screen . autumn, pp. — . outlaw, lucius: , ‘african, african american, africana philosophy’ in pittman, pp. – . perpener, john o.: , african-american concert dance: the harlem renaissance and beyond, urbana: university of illinois press. pittman, john p. (ed): , african-american perspectives and philosophical traditions, newyork: routledge. salaam, abdel: , personal interview with author, new york, june. scarry, elaine: , on beauty and being just, princeton, nj: princeton university press. thompson, robert f.: , flash of the spirit: african & afro-american art & philosophy, new york: first vintage books edition. west, cornel: , ‘philosophy and the afro-american experience,’ in lott and pittman ( ), pp. – . massachusetts institute of technology massachusetts avenue room - cambridge, ma usa e-mail: defrantz@mit.edu thomas f. defrantz is associate professor of music and theater arts at mit. a director and choreographer, he has affiliations with the drama league of new york, the theater offensive of boston, and the performance research group slippage: performance interventions in culture and technol- ogy, in residence at mit. he is editor of dancing many drums: excavations in african american dance (university of wisconsin press, ) and author of dancing revelations: alvin ailey’s embodiment of african american culture (oxford university press, ). thomas f. defrantzthomas f. defrantz wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ facial symmetry and the perception of beauty psvchonomic bulletin & review , ( ), - facial symmetry and the perception of beauty giluan rhodes university of western australia, nedlands, perth, western australia and university of canterbury, christchurch, new zealand and fiona proffitt, jonathon m. grady, and alex sumich university of canterbury, christchurch, new zealand evolutionary, as well as cultural, pressures may contribute to our perceptions of facial attractiveness. biologists predict that facial symmetry should be attractive, because it may signal mate quality. we tested the prediction that facial symmetry is attractive by manipulating the symmetry of individual faces and observing the effect on attractiveness, and by examining whether natural variations in symmetry (between faces) correlated with perceived attractiveness. attractiveness increased when we increased symmetry, and decreased when we reduced symmetry, in individual faces (experiment ), and natural variations in symmetry correlated significantly with attractiveness (experiments and la). perfectly symmetric versions, made by blending the normal and mirror images of each face, were preferred to less symmetric versions of the same faces (even when those versions were also blends) (experiments and ). similar results were found when subjects judged the faces on appeal as a potential life part- ner, suggesting that facial symmetry may affect human mate choice. we conclude that facial symmetry is attractive and discuss the possibility that this preference for symmetry may be biologically based. the question of what makes a face attractive, and whether our preferences come from culture or biology, has fascinated scholars for centuries. variation in the ideals of beauty across societies and historical periods suggests that standards of beauty are set by cultural con- vention. recent evidence challenges this view, however, with infants as young as months of age preferring to look at faces that adults find attractive (langlois et ai., ), and people from different cultures showing con- siderable agreement about which faces are attractive (cun- ningham, roberts, wu, barbee, & omen, ; jones & hill, ; see langlois & roggman, , for a review). these findings raise the possibility that some standards of beauty may be set by nature rather than culture. con- sistent with this view, specific preferences have been iden- tified that appear to be part of our biological rather than our social heritage (langlois & roggman, ; langlois, roggman, & musselman, ; perrett, may, & yoshi- kawa, ; rhodes & tremewan, ). for example, average facial configurations are attractive (langlois & this research was supported by grants from the department of psy- chology. university of canterbury. the australian research council. and the university of western australia. we thank graham byatt, ian mcl.ean, johanna roberts. and leslie zebrowitz for stimulating dis- cussions about this work. and rotem kowner, nicola bruno. randy larsen. leslie zebrowitz. and an anonymous reviewer for helpful com- ments on an earlier version of the manuscript. we also thank graham byatt for assistance with stimulus construction. linda jeffery for as- sistance with the figures. and alison clark and catherine hickford for assistance with data collection and statistical analysis in experi- ment i a. correspondence should be addressed to g. rhodes. depart- ment of psychology. university of western australia. ncdlands, perth. wa . australia (e-mail: gill@psy.uwa.edu.au). roggman, ; langlois et ai., ; rhodes & treme- wan, ). such a preference would be adaptive if sta- bilizing selection operates on facial traits (symons, ), or if averageness is associated with resistance to patho- gens, as some have suggested (gangestad & buss, ; thornhill & gangestad, ). evolutionary biologists have proposed that a prefer- ence for symmetry would also be adaptive because sym- metry is a signal of health and genetic quality (palmer & strobeck, ; parsons, ; thornhill & moller, ; watson & thornhill, ). only high-quality individu- als can maintain symmetric development in the face of environmental and genetic stresses. symmetric bodies are certainly attractive to humans and many other animals (brooks & pomiankowski, ; concar, ; moller & pomiankowski, ; thornhill & gangestad, ; wat- son & thornhill, ), but what about symmetric faces? biologists suggest that facial symmetry should be at- tractive because it may signal mate quality (ridley, ; swaddle & cuthill, ; watson & thornhill, ). high levels offacial asymmetry in individuals with chro- mosomal abnormalities (e.g., down's syndrome and tri- somy ; for a review, see thornhill & moller, ) are consistent with this view, as is recent evidence that facial symmetry levels correlate with emotional and psycholog- ical health (shackelford & larsen, ). in this paper, we investigate whether people can detect subtle differences in facial symmetry and whether these differences are as- sociated with differences in perceived attractiveness. recently, kowner ( ) has reported that faces with normal levels of asymmetry are more attractive than per- fectly symmetric versions of the same faces.:' similar re- sults have been reported by langlois et al. ( ) and sam- copyright psychonomic society, inc. rhodes, proffitt, grady, and sumich uels, butterworth, roberts, graupner, and hole ( ). together, these studies suggest that symmetry is not at- tractive in faces. other results, however, suggest that fa- cial symmetry is attractive. in particular, natural varia- tions in symmetry appear to covary with attractiveness (grammer & thornhill, ; jones & hill, , for some ethnic groups; zebrowitz, voinescu, & collins, ; but see jones & hill, , for other ethnic groups; langlois et ai., ). how can these two conflicting sets of results be recon- ciled? one possibility is that symmetry is attractive within the normal range of variation, but that perfect symmetry is not preferred. to understand why this might be so we need to distinguish between two kinds of asymmetry in faces: fluctuating and directional asymmetries. fluctu- ating asymmetries are randomly distributed (with re- spect to the direction of the asymmetry) across individ- uals in a population, so that there is no consistent left- right bias in the population as whole. these asymmetries result from environmental or genetic stresses, and so may be reliable indicators of mate quality. unlike fluc- tuating asymmetries, directional asymmetries have a consistent bias (to the left or right) across a population, are not produced by stresses during development, and are not potential indicators of mate quality. directional asymmetries in faces include systematic biases for the left side of face to be larger (previc, ) and more ex- pressive (borod, ) than the right. because of these directional asymmetries, a face will be somewhat asym- metric in the absence of any stresses during development; that is, perfect symmetry will not be the norm. there- fore, it is possible that symmetry is attractive within the naturally occurring range of symmetry levels because variations within that range primarily reflect fluctuating asymmetries, but that perfect symmetry is unattractive because it is abnormal. ' there is, however, another possible resolution of the two sets of results. the studies reporting that perfect symmetry is unattractive have compared normal faces with perfectly symmetric chimeras, constructed by re- flecting each half of the face about the vertical midline (yielding two chimeras for each face). however, these chimeras may not be appropriate for assessing the at- tractiveness of perfect symmetry in faces because they can contain structural abnormalities that make them look strange. part of the problem stems from the directional size asymmetry in faces, which means that for many faces, one chimera will be wider, and the other narrower, than a normal face (i.e., the chimeras may have width- height aspect ratios outside the normal range). features in the center of the face may also be abnormal in chimeras. for example, if the nose bends to one side of the face, then one chimera will have an abnormally wide and the other an abnormally narrow nose. an asymmet- rically positioned mouth will generate similar distortions in the chimeras. slight deviations from frontal views in the original photographs will compound these problems and introduce new abnormalities (e.g., the eyes may be- come abnormally narrow-set or widely spaced in the chi- meras if there is any rotation around the main axis of the head). given that attractiveness decreases with distortion from a prototypical facial configuration (see, e.g., rhodes & tremewan, ), these abnormalities are likely to make the chimeras unattractive, thus offsetting any pref- erence for symmetry. an alternative way to construct perfectly symmetric faces that does not introduce structural abnormalities is to blend the normal and mirror images of each face. this technique results in more natural looking symmetric faces that might well be considered attractive. we therefore de- cided to reassess the attractiveness of perfect symmetry using this technique to make perfectly symmetric faces. we also investigated whether the attractiveness of individ- ual faces could be manipulated by varying their level of symmetry across a wider range of symmetry levels than is normally found in faces. this manipulation provides a strong test of how the level of symmetry influences facial attractiveness. it also tests kowner's ( ) claim that ob- servers are not tuned to perceive the low degree of asym- metry present in normal faces. if she is correct, observers should be unable to distinguish normal (asymmetric) faces from perfectly symmetric versions of the same faces. langlois and her colleagues ( ) used a similar tech- nique to create symmetric versions of individual faces when they blended the forward and mirror images of slightly different shots of each face to make a symmetric -image version of each face. however, they did not use these images to assess the attractiveness of symmetry. rather, they compared these same-face composites with a composite made from different individuals in a suc- cessful attempt to show that the attractiveness of com- posite or average faces was not simply the result of their symmetry or an artifact of combining multiple images. experiment in experiment , we varied the level of symmetry in individual faces and examined the effect on attractive- ness. there were four versions of each face (figure ). one of these was a perfectly symmetric version created by blending the normal and mirror images of the face. the others were ( ) a high-symmetry version, created by reducing the differences between the original face and its perfectly symmetric version by %,( ) the original face showing a normal level of symmetry, and ( ) a low- symmetry version, created by increasing the differences between the original face and its perfectly symmetric ver- sion by % (see below for details). subjects rated all versions of all the faces on attrac- tiveness. if a preference for symmetry is part of our evolu- tionary heritage, as conjectured, then a preference for symmetry should ultimately influence mate choice. there- fore, we also asked subjects to rate opposite-sex faces on appeal as a potential life partner. the order of attractive- ness and mate-choice ratings was counterbalanced across subjects. finally, we asked subjects to rate all versions low normal high facial symmetry perfect symmetry figure l. low-, normal-, high-, and perfect-symmetry versions for three faces from experiment l. of all the faces on symmetry level to determine whether or not they were sensitive to different levels of symme- try in faces. method subjects. sixty-four university students ( males, females) re- ceived $ each for participating. stimuli. digitized black-and-white photographs of young adult faces ( males, females) were used. all were frontal views, with neutral expressions, taken with symmetric lighting. blemishes, ear- rings, clothing, and stray pieces of hair were removed using the cloning stamp tool in photoshop. to correct for any slight deviations from ver- ticality in the images, the best-fitting line (found by eye) through the midpoints of the lines joining the inner eye corners, the outermost edges of nose, and the outer corners of mouth was aligned to vertical. the mid- point between the eyes was centered on the screen before a face was manipulated. a fixed set of landmark points (a subset of the points used in rhodes & tremewan, ) outlining the shape and po- sition of the internal features and face outline was located on each face. perfectly symmetric versions were created using gryphon's morph software to average the normal and mirror images of each face. this procedure first averages the locations of the points and then averages the gray-level values in corresponding regions of the face (for details. see beale & keil, ). to make high- and low-symmetry versions of a face. corresponding points are found (by the program) on the original face and its perfectly symmetric version, and all distances between the corresponding points are reduced (to create a high-symmetry version) or increased (to make a low-symmetry version) by %. the gray lev- els from the original face are then mapped onto the new configuration. an oval mask hid most of the neck and the top of the head (figure ). the resulting face images measured approximately x cm and had a resolution of pixels per inch. one version of each face was as- signed to each of four booklets, with booklets balanced for sex and sym- metry level. additional male-only and female-only booklets were cre- ated for use in the mate appeal ratings. procedure. each subject rated the attractiveness (i = not at all at- tractive, = very attractive) and symmetry (i = not at all symmetric, = perfectly symmetric) of all four versions of all faces (different versions in different booklets. as described above) and rated all four ver- sions of all opposite-sex faces for mate appeal ("how appealing is this person as a life partner?" i = not at all appealing, = very ap- pealing). order of attractiveness and mate appeal ratings was counter- balanced with order of booklets. symmetry ratings were always made last so that attention was not drawn to symmetry before the attractiveness and mate appeal ratings were made. subjects were tested individually. results and discussion reliability for attractiveness, mate appeal, and sym- metry ratings was assessed separately for male and fe- male subjects and faces. all ratings were highly reliable, with cronbach alpha's ranging from . to . . three- way analyses of variance (anovas) were carried out on the mean attractiveness and symmetry ratings. with sex rhodes, proffitt, grady, and sumich .-------------------. -- -- female faces -.- malefaces i gi :ii tween symmetry level and sex of face, symmetry had qual- itatively similar effects on the attractiveness of male and female faces. simple tests of main effects showed that the effect of symmetry was significant for both male [f( , ) = . , p < . ] and female [f( , ) = . , p < . ] faces. perfect symmetry was signifi- cantly more attractive, and low symmetry significantly less attractive, than normal symmetry in both cases (all ps < . ), but ratings of normal and high symmetry did not dif- fer significantly for either male or female faces. none of the sex differences at the different symmetry levels were significant by simple tests of main effects (all fs < . ). mate appeal ratings (opposite-sex faces only). as for attractiveness, there was a significant main effect of symmetry level [f( , ) = . ,p < . ], which was qualified by an interaction with sex ofsubject [f( , ) = . ,p < . ; figure , bottom]. simple tests of main effects showed significant effects of symmetry level for both male [f( , ) = . , p < . ] and female [f( , ) = . , p < . i] subjects, but males found perfectly symmetric faces more appealing as potential life partners than did females [f(l, ) = . , p < . ]. the appeal of perfect symmetry was stronger for males than females, but males and females did not differ on any of the other symmetry levels (all fs < . ). this sex difference is consistent with evidence that physical ap- pearance plays a larger role in the mate choices of males than of females (buss, ; buss & schmitt, ). we note, however, that parental investment theory (trivers, ) predicts the opposite sex difference. on that ac- count, females should be more attuned to potential sig- nals of mate quality than males because they make a greater parental investment than males. symmetry ratings. there was a significant main ef- fect of symmetry level [f( , ) = . ,p < . ]. therefore, subjects were sensitive to the differences in symmetry levels within faces produced by our distortions, even though these differences were quite subtle (due to the approximate bilateral symmetry offaces). symmetry level interacted with sex offace [f( , ) = . ,p < . ]. simple tests of main effects showed that the effect of symmetry was significant for both male [f( , ) = . , p < . ] and female [f( , ) = . , p < . ] faces, with symmetry ratings increasing signifi- cantly from one symmetry level to the next in both cases (male ms = . , . , . , and . ; female ms = . , . , . , and . for low, normal, high, and perfect symmetry, respectively; all ps < . ). there was a marginal interac- tion between symmetry and sex of subject [f( , ) = . , p < . ], with a wider range of ratings for males ( . - . ) than for females ( . - . ). correlations. mean ratings were calculated for each face for each rating scale. table shows pearson product- moment correlations between mean ratings of symmetry and attractiveness, symmetry and mate appeal, and attrac- tiveness and mate appeal for the normal (undistorted) versions of the faces as well as for all versions (low, nor- perfecthigh symmetry normallow l--or-----...,...----.,..-----.---' low normal high perfect symmetry - - malesubjects ~ female subjects s iii :ii c iii gi :ii iii iii gl c gi >.. u iii...... iii( ii gl q. q. iii( of subject as a between-subjects factor and sex of face and symmetry level as repeated measures factors. a two- way anoya was carried out on the mean mate appeal ratings, with sex of subject as a between-subjects factor and symmetry level as a repeated measures factor. for each analysis, planned t tests were carried out to test for differences between symmetry levels. attractiveness ratings. there was a significant main effect of symmetry level [f( , ) = . , p < . ], qualified by an interaction between symmetry level and sex offace [f( , ) = . ,p < . ; figure , top]. in- spection of figure shows that despite the interaction be- figure . mean attractiveness ratings (top) as a function of symmetry level and sex of face in experiment . mean mate ap- peal ratings (bottom) as a function of symmetry level and sex of subject in experiment . se bars are shown. facial symmetry table pearson product-moment correlations between mean ratings of symmetry and attractiveness, symmetry and mate appeal, and attractiveness and mate appeal in experiments and ia experiment i subjects experiment a subjects all male female all male female (all faces) (female faces) (male faces) (all faces) (female faces) (male faces) normal faces df= df= df> df= df= df= symmetry and attractiveness . t . * . . t al t . symmetry and mate appeal . * . s* . . a t -. attractiveness and mate appeal . § . § . § . s§ . § . § all versions df= df > df= df= df= df= symmetry and attractiveness . § . § . t . § § . t symmetry and mate appeal . § . t . t . § . § .is ;\ttractiveness and mate appeal . s§ . § . § . § . § . s§ note-separate correlations are shown for normal (undistorted) faces and all versions (low, normal, high, and perfect symmetry) offaces. only opposite-sex faces were rated for mate appeal. *p < . . "p < .os. lp < . i. \p < . i. mal, high, and perfect symmetry versions). in addition to overall correlations for all subjects and faces, correla- tions are also shown for opposite-sex ratings, which are more directly relevant to assessing the role of symmetry in mate choice. for all faces (male and female) and ratings by all the subjects, all the correlations were significant except for that between mate appeal and symmetry in the normal faces, which was only marginally significant. these re- sults clearly show that facial symmetry is attractive, and they corroborate our evidence for the attractiveness of symmetry obtained by direct manipulation offacial sym- metry. ratings of attractiveness and mate appeal were highly correlated, suggesting that ratings of attractive- ness may have been based primarily on an assessment of sexual attractiveness, rather than other aspects of attrac- tiveness, such as cuteness. for opposite-sex ratings when all versions of the faces were considered, symmetry was again positively corre- lated with attractiveness and mate appeal. when only normal faces were considered, the correlations were sim- ilar, but failed to reach significance with the smaller num- ber of faces. the preference for symmetry appeared to be stronger for males rating female faces than for females rating male faces. the effect of symmetry on attractiveness did not de- pend on a face's initial attractiveness. the increase in at- tractiveness from the normal to the perfectly symmetric version of each face was uncorrelated with initial attrac- tiveness (r = . , df> , n.s.). the corresponding cor- relation for mate appeal was . (n.s.). the scatterplots showed no hint of curvilinear relations between initial at- tractiveness or mate appeal and the enhancing effect of in- creased symmetry. these results do not support langlois et al.s ( ) conjecture that only exceptionally un- attractive faces are improved by an increase in symmetry. they found that only very unattractive faces increased in attractiveness when made perfectly symmetric, but this re- sult may reflect the use of perfectly symmetric chimeras. a normal face would have to be exceptionally unattractive to be rated less attractive than such strange looking images. our results indicate that facial symmetry is attractive. they should not, however, be taken to mean that sym- metry is the only determinant of facial attractiveness. if it were, then perfectly symmetric faces would all have been judged equally attractive, and they were not. mean ratings (averaged across subjects) for the perfectly sym- metric images ranged from . to . (means for the nor- mal faces ranged from . to . ), and these judgments were highly consistent, with male and female subjects' ratings correlating . (df= ,p < . ). nor do these ratings indicate that symmetry is strikingly beautiful. nevertheless, they do show that people are sensitive to different levels of symmetry in faces, and they generally find symmetry attractive. experiment la in experiment , each subject rated the faces on attrac- tiveness, mate appeal, and symmetry, raising the possibil- ity that the correlations reported above were inflated by carryover effects from one rating scale to another> given that subjects rated a large number of images on each scale (blocked by scale), subjects would be unlikely to remem- ber exactly how they had rated any particular image on an earlier scale. nevertheless, there may be a more general carryover effect from thinking about a face's attractiveness (or mate appeal) before rating its symmetry, which could inflate the correlations between symmetry and attractive- ness (or mate appeal). in experiment a, therefore, we tested additional subjects to determine whether significant correlations between symmetry and attractiveness, and symmetry and mate appeal, would still be found when dif- ferent subjects rated the faces on each scale. method subjects. one hundred and twenty-eight university students ( males. females) each received either $s or course credit for participating. of these. ( males, females) rated the faces on symmetry. ( males. females) on attractiveness, and ( males. females) on mate appeal. fewer subjects rated attractiveness and mate appeal be- cause their data could be combined with the data from subjects in ex- periment i who had rated those scales first. rhodes, proffitt, grady, and sumich procedure. the procedure was identical to that of experiment i ex- cept that each subject rated the faces on only one rating scale. results and discussion all ratings were highly reliable, with cronbach alphas ranging from . to . . mean symmetry, attractive- ness, and mate appeal ratings were calculated for each image using ratings from separate groups of subjects. the symmetry ratings were calculated using the data from the new group of subjects only because no subjects in experiment had rated symmetry first. attractiveness and mate appeal ratings were calculated by combining the data from the new subjects with data from those subjects in experiment who had rated that scale first. table shows that the correlations between symmetry and attractiveness and between symmetry and mate ap- peal were very similar to those obtained in experiment . of these correlations (see table , rows , , , and ), increased from experiment to experiment a, and decreased, suggesting that the use of the same sub- jects to make all the ratings did not consistently inflate the correlations. most importantly, we replicated the sig- nificant correlations between symmetry and attractive- ness for normal (undistorted) versions of the faces and for all versions of the faces. we also replicated the cor- relation between symmetry and mate appeal for all ver- sions of the faces, but not the marginal correlation for normal faces found in experiment . the correlations be- tween attractiveness and mate appeal were high, but con- sistently lower than in experiment . as in experiment , males appeared to have a stronger preference for symmetry in female faces than females had for symmetry in male faces. males showed significant cor- relations between symmetry and attractiveness, and sym- metry and mate choice, when rating normal female faces (cf. marginal correlations in experiment ). for females, neither correlation was significant for normal faces in ei- ther experiment, and the correlation between symmetry and mate appeal, which was significant for ratings of all versions ofthe faces in experiment , was not significant. as in experiment , we found no support for the notion that symmetry enhances only unattractive faces. the dif- ference in attractiveness between normal and perfectly symmetric versions of faces was uncorrelated with ini- tial attractiveness (r = - . , df = , n.s.), and the corre- sponding correlation for mate appeal was -. (n.s.). the scatterplots showed no sign of curvilinear relationships. taken together, the correlations obtained in experi- ments and a suggest that higher levels of symmetry enhance the attractiveness and mate appeal of a face. these effects are seen most clearly when an extended range of symmetry levels is used (all versions), but are still appar- ent when only the normal faces are considered. the opposite-sex ratings indicate that males and females both find symmetry attractive in opposite sex faces, but that the preference may be stronger for males than fe- males. only males showed replicable correlations be- tween symmetry and mate appeal. experiment in experiment , we created perfectly symmetric faces by blending each face with its mirror image. this tech- nique has the advantage of creating natural-looking sym- metric faces. however, blends themselves may be more attractive than normal faces, because they are more av- erage (langlois & roggman, ), because they have smoother skin texture (benson & perrett, ), or both. therefore, our perfectly symmetric versions of faces could have been attractive because they were blends rather than because they were symmetric. two points argue against the interpretation of our re- sults as solely due to blending artifacts. first, our per- fectly symmetric faces were created by blending two face images, and two-face blends were not more attractive than the original faces in langlois and roggman's ( ) study. sixteen faces had to be entered into the compos- ites before they were more attractive than the original faces. second, blending artifacts cannot explain the full pattern of our results because reducing the symmetry of normal faces decreased attractiveness, and neither the normal- nor low-symmetry versions were blends. nevertheless, in experiment we attempted to rule out a blending account of our results by comparing the at- tractiveness of faces at three symmetry levels (normal, high, and perfect), all of which were blends (see figure and below for details). on each trial, subjects were shown two versions of the same face at different levels of sym- metry and were asked to choose the more attractive one." three kinds of pairs were presented for each face: the normal- and high-symmetry versions, the high- and perfect-symmetry versions, and the normal- and perfect- symmetry versions of that face. in each case, subjects should select the more symmetric version in the pair if symmetry is attractive, and given that all the images were blends, any such symmetry preference would be unlikely to result simply from a blending artifact. alternatively, if the preference for perfectly symmetric faces in experi- ment was due solely to a blending artifact, we should find no preference for perfectly symmetric images in this study. in addition to choosing the more attractive face in each pair, subjects were also asked to choose the face with more appeal as a potential life partner (mate appeal) (for opposite-sex faces only). in computer graphics, a distinction is made between two aspects of an image that can be manipulated inde- pendently, namely "shape" and "texture" information. shape information refers to the spatial layout of land- mark points or features in an image, and texture informa- tion refers to variations in the pattern of light and dark (or colors) across an image. asymmetries can also be classified as asymmetries in shape or texture. an exam- ple of a shape asymmetry would be a difference in the position of the eyes. an example ofa textural asymmetry would be a difference in brightness (or color) between corresponding regions on the two sides of a face (e.g., one pale eye and one dark eye). blending the forward and normal high symmetry facial symmetry perfect figure . normal-, high-, and perfect-symmetry versions for three faces from experiment . mirror versions of a face results in an image with perfect bilateral symmetry of both shape and texture. the ma- nipulation used to produce the high- and low-symmetry images in experiment i (warping each face halfway to- ward, or away from, its perfectly symmetric configura- tion), however, altered only shape symmetry. reducing shape symmetry reduced attractiveness, but increasing shape symmetry did not increase attractiveness. in ex- periment , we investigated whether attractiveness (and mate appeal) would increase if both texture and shape symmetry were increased in the high-symmetry versions. kowner ( ) has hypothesized that people are not sensitive to the subtle asymmetries present in normal faces. if she is correct, subjects should be unable to discrimi- nate any symmetry differences between the two images in each pair. to test this claim, we also asked people to choose the more symmetric face from each pair of images. method subjects. sixty university students ( males. females) received $ each for participating. stimuli. new normal versions of each face were created by blending ( : ) the low- and high-symmetry versions from experiment i (fig- ure . left). high-symmetry versions (figure . middle) were created by blending the forward and mirror images of each face in a : ratio (see experiment i for general details of the blending process). if one considers a continuum of images with the normal face on the left. the mirror image on the right. and the perfectly symmetric image lying mid- way in between. then this : blend morphs the normal face halfway toward its perfectly symmetric version. in this way. we can create a high-symmetry version of each face in which both shape and textural symmetry have been increased by %. perfect-symmetry versions were those used in experiment i (figure . right). these images were displayed in the same oval masks as in experiment i. three pairings were created for each face. one consisting of the normal- and high-symmetry versions. one consisting of the high- and perfect- symmetry versions. and the other consisting of the normal- and perfect- symmetry versions. each of the three face pairs for a face was assigned to a different booklet. with booklets balanced for sex of face. type of pair. and left-right arrangement of faces in the pairs (less symmetric face on left or right). additional male-only and female-only booklets were created for usc in the mate appeal ratings. procedure. each subject made forced choices on attractiveness. mate appeal (opposite-sex faces only). and symmetry for all the face pairs in all the booklets. with trials blocked by rating scale. order of at- tractiveness and mate appeal choices was counterbalanced with order of booklets. symmetry choices were always made last so that attention would not be drawn to symmetry before the attractiveness and mate ap- peal judgments were made. note that symmetry judgments were in- cluded to determine whether subjects could accurately detect the dif- ferences in symmetry introduced by our manipulations. and not to determine whether symmetry correlated with attractiveness (or mate appeal). therefore. we did not obtain the symmetry and attractiveness (and mate appeal) judgments from independent groups of subjects. rhodes, proffitt, grady, and sumich results and discussion the dependent variable for each rating scale was a symmetry preference score, calculated as the proportion of trials on which the more symmetric member of each pair was chosen.f a score greater than . indicates a pref- erence for the more symmetric members of the pairs. separate three-way anovas were carried out on the mean symmetry preference scores for attractiveness and sym- metry choices, with sex of subject as a between-subjects factor and sex of face and pair type as repeated measures factors. the levels of pair type were normal-high, high- perfect, and normal-perfect. a two-way anova was car- ried out on the mean symmetry preference scores for mate appeal choices, with sex of subject as a between- subjects factor and pair type as a repeated measures factor. planned t tests were carried out to test whether symmetry preferences were significantly greater than . . tukey tests were used for other, unplanned comparisons. attractiveness. for all three pair types, there was a significant preference for the more symmetric face in the pair (i.e., mean preference scores were significantly greater than . ; all ts > . ,ps < . ). therefore, when choosing between two versions of the same face, subjects consistently preferred the more symmetric one. there was a significant main effect of pair type [f( , ) = . , p < . i; figure ]. not surprisingly, the strong- est symmetry preference was for the pairs with the great- est symmetry difference, namely the normal-perfect pairs (m = . ). the next highest preference was for normal-high pairs (m = . ), followed by high-perfect pairs (m = . , all ps < . , tukey tests). there was a marginal interaction between pair type and sex of subject . iii attractiveness . mate appeal gl . u c: . e gl "§ . d. e q; e . e >- ul . . nh hp np type of comparison figure . mean symmetry preference as a function of type of comparison (pair type) in experiment . choice pairs were al- ways versions of the same face. symmetry preference values greater than . indicate a bias to select the more symmetric member of each pair. se bars are shown. nh, choices between normal- and high-symmetry versions; hp, choices between high- and perfect-symmetry versions; np, choices between normal- and perfect-symmetry versions. [f( , ) = . ,p < . ]. males had stronger symme- try preferences than females for normal-high (m = . , males; m = . , females) and high-perfect (m = . , males; m = . , females) pairs, but not for normal-perfect (m = . , males; m = . , females) pairs. these results confirm the attractiveness of facial symmetry and dem- onstrate that it is not a blending artifact. mate appeal. the results were very similar to those obtained for attractiveness choices. for all three pair types, there was a significant preference for the more symmetric member of the pair (all ts > . , ps < . i). there was a significant main effect of pair type [f( , ) = . , p < . ; figure ], with the highest symmetry prefer- ence for normal-perfect pairs (m = . ), followed by normal-high pairs (m = . ), followed by high-perfect pairs (m = . , all ps < . i, tukey tests). there was also a significant main effect of sex ofsubject [f(l, ) = . , p < . ], with males (m = . ) showing a stronger over- all preference for symmetry than females (m = . ). symmetry. in this task, a symmetry preference repre- sents accurate performance (i.e., the most symmetric face was chosen as more symmetric). for all three pair types, performance was significantly better than chance (all ps < . i). there was a significant main effect of pair type [f( , ) = . , p < . ], with best perfor- mance on normal-perfect pairs (m = . ), followed by normal-high pairs (m = . ), followed by high-perfect pairs (m = . , allps < . , tukey tests). the greater sen- sitivity to the symmetry difference in normal-high than in high-perfect pairs may be a perceptual learning effect re- sulting from more experience at discriminating variations in symmetry close to normal levels. this ordering of sen- sitivity to symmetry differences in the three types of pairs matches, and may account for, differences in the strength of the symmetry preference for the three types of pair in the attractiveness judgments (figure ). the main effect of pair type was qualified by a significant interaction with sex offace [f(l, ) = . ,p < . ]. the pattern of accuracy found for the three pair types (see above) did not differ for male and female faces (see above), but accu- racy was higher for male than for female faces in the nor- mal-high and normal-perfect pairs. there was a signifi- cant main effect of sex of face [f(l, ) = . , p < . ], which was qualified by an interaction with sex of subject [f( i , ) = . , p < . ]. symmetry was judged more accurately in male (m = . ) than in female faces (m = . ), and this difference was greater for male (m = . , male faces; m = . , female faces) than for female subjects (m = . , male faces; m = . , female faces). general discussion we have shown that the attractiveness of individual faces can be in- creased by increasing the bilateral symmetry of those faces. that attrac- tiveness is reduced when symmetry levels are decreased. and that per- fectly symmetric faces. although not strikingly beautiful, are preferred to faces with lower levels of symmetry. because faces are approxi- mately bilaterally symmetric, our manipulation of symmetry did not dramatically alter the faces (see figures i and ). nevertheless people were sensitive to the rather subtle differences in symmetry that resulted, and preferred higher levels of symmetry. we also found that attractiveness was associated with natural varia- tions in symmetry between different faces (for both undistorted faces and sets of images covering an extended range of symmetry levels). these results corroborate our experimental evidence for the attractive- ness offacial symmetry, described above. in addition, they replicate ear- lier positive correlations between symmetry and attractiveness (gram- mer & thornhill, ; jones & hill, ; zebrowitz et ai., ). they are also consistent with a recent report that symmetry differences between identical twins correlate positively with differences in attrac- tiveness (mealey & townsend, ). both male and female subjects found symmetry attractive in opposite- sex faces, but the preference appeared to be stronger for males. this sex difference is consistent with the finding that physical appearance plays a larger role in the mate choices of males than females (buss, ; buss & schmitt, ). lt is less consistent with parental investment theory (trivers, ), which predicts greater female sensitivity to sig- nals of mate quality (assuming that symmetry is a signal of mate qual- ity) because their reproductive investment is greater than that of males. we also note that grammer and thornhill ( ) found very similar correlations between facial symmetry and attractiveness of opposite- sex faces for males and females, and suggest that the sex difference found in our experiments be viewed with caution. kowner ( ) and others (langlois et al., ; samuels et ai., ) have reported that perfect symmetry in faces is unattractive. we suggest that their results may reflect the use of perfectly symmetric chimeras, which introduce structural abnormalities (see introduction) and are therefore likely to be unattractive. our results indicate that when these abnormalities are avoided, by blending normal and mirror images of faces, the resulting perfectly symmetric images are more attractive than the original faces. moreover, this result did not appear to be an ar- tifact of the attractiveness of blends per se because perfectly symmetric blends were preferred to other, less symmetric, blends. since we began these studies, swaddle and cuthill ( ) have re- ported that symmetry is unattractive, using a similar symmetry manip- ulation to ours. we suspect that their result is due to differences in fa- cial expression that covaried with symmetry level in their study. expression was not controlled, and the sample face shown in their paper had a small, asymmetric smile, which disappeared as symmetry in- creased. smiles are attractive (see, e.g., cunningham et ai., ), so if this sample face is typical, then swaddle and cuthill's faces would have become less attractive as symmetry increased and they lost their smiles. symmetric smiles may also be unnatural (kowner, ), which could restrict the appeal of perfect symmetry for smiling faces. we are cur- rently investigating the effects of expression on the attractiveness of symmetry. another feature of swaddle and cuthill's stimuli that could have minimized the appeal of symmetry is that only the internal fea- tures offaces were shown, thereby eliminating cues to mate quality pro- vided by the jaw and chin. development of this part of the face is strongly influenced by sex hormones, which stress the immune system (thornhill & gangestad, ), and symmetry in that region may there- fore provide a powerful cue to mate quality. our results show that when emotional expression is carefully controlled (and neutral), and the whole face is visible, symmetry is attractive. similar results have re- cently been obtained by perrett and his colleagues (perrett, burt, lee, rowland, & edwards, ). the hypothesis that facial symmetry is attractive was derived from evolutionary theory. we therefore collected mate appeal ratings, as well as attractiveness ratings, to gain preliminary information about whether symmetry might influence human mate choice. the mate appeal results were similar to those described above for attractiveness, with more sym- metric images being rated as more appealing as a potential life partner than less symmetric images. the sex difference found for attractiveness was even greater for mate appeal ratings, with only males showing replicable correlations between symmetry and mate appeal. more di- rect measures of the impact of facial symmetry on reproductive behav- ior will be needed to determine whether facial symmetry (like bodily symmetry, thornhill & gangestad, ) influences mate choice, but the present results suggest that it may do so. facial symmetry in the introduction, we noted that the presence of directional asym- metries in faces means that some degree of asymmetry is normal, and that not all facial asymmetries would indicate a poor-quality mate. lt was not, therefore, obvious that perfect facial symmetry would be at- tractive (or even that it should be considered optimal in a system tuned to detect fluctuating asymmetries). does our finding that people prefer perfectly symmetric faces to less symmetric versions mean that perfect symmetry is attractive despite its abnormality? we suspect not, because directional asymmetries in resting faces appear to be very small, which means that perfect symmetry is not abnormal in the sense of deviating markedly from the population mean. rhodes, surnich, and byatt (in press) found that the average female face (made by averaging female faces together to eliminate fluctuating, but not directional, asymme- tries) and its perfectly symmetric counterpart were perceived as equally symmetric. the male average was considered less symmetric than its perfectly symmetric counterpart, but still appeared more symmetric than any individual male face. therefore, directional asymmetries in faces (especially female faces) appear to be very small, so most facial asymmetries would be fluctuating asymmetries, which could potentially signal mate quality. it is an open question whether the slight degree of asymmetry present in the average male face (due to directional asym- metries) would be more attractive than perfect symmetry. future stud- ies using a finer grained manipulation of symmetry levels than that used in the present experiments would be needed to answer this question. if facial symmetry is a standard of beauty set by nature rather than culture, then how might a preference for symmetry have evolved? in the introduction, we raised the possibility that facial symmetry, like sym- metry in other morphological traits (for an extensive review, see thorn- hill & moller, ), may be a reliable signal of health and genetic qual- ity. if it is, individuals who prefer to mate with symmetric individuals would have higher fitness, on average, than those without a preference for symmetric mates, and the symmetry preference would be selected for. this possibility receives preliminary support from shackelford and larsen's ( ) results, described above. there are, however, other ways that a symmetry preference could evolve. given that symmetry is heritable (moller & thornhill, ), the offspring of individuals who chose symmetric mates would tend to be symmetric and therefore popular as mates (as long as the preference for symmetry was also heritable). this sort of feed-forward mechanism can maintain preferences in a population (fisher, , ). a prefer- ence for facial symmetry could also be a by-product of some general sensitivity to symmetric patterns that has evolved for reasons that have nothing to do with assessing mate quality." for example, sensitivity to symmetry could have evolved because it is useful in form perception generally. support for this "perceptual bias" hypothesis comes from simulation studies showing that symmetry preferences evolve when connectionist networks are trained to recognize patterns (enquist & arak, ; johnstone, ) and from evidence that symmetric pat- terns generally are attractive (corballis & beale, ). note that neither the feed-forward mechanism nor the perceptual bias account requires that symmetry signals mate quality or that a symmetry preference is specific for faces (or bodies) for such a preference to evolve. our results are consistent with the notion that symmetry is a standard of beauty set by nature, but they do not allow us to rule out an alterna- tive, culturally based account. cross-cultural and developmental stud- ies are potentially informative. evidence of cross-cultural agreement on the attractiveness offacial symmetry would support the biological view, as would evidence of early emergence of the preference (so that there is little opportunity for cultural shaping) or emergence at puberty (trig- gered by the sex hormones that motivate the search for a mate). addi- tional studies are also needed to replicate and extend shackelford and larsen's ( ) initial evidence for an association between facial sym- metry and health. several commentators have suggested that a preference for symmetry may underlie our preference for averageness because average faces are more symmetric than other faces (see langlois et al., , for a review). our finding that symmetry is attractive adds plausibility to this conjec- ture, which was advanced in the absence of good evidence that symme- try is indeed attractive. nevertheless, we think it unlikely that a preference for symmetry will completely account for the attractiveness of average- rhodes, proffitt, grady, and sumich ness. langlois and her colleagues ( ) have shown that a blend of a large number of different faces is more attractive than perfectly symmet- ric versions of individual faces like those used here. this result suggests that an average facial configuration, obtained by blending many different faces, is more attractive than perfect symmetry. weare currently investi- gating the precise relationship between preferences for symmetry and av- erageness. our results suggest that symmetry and averageness make in- dependent contributions to attractiveness (rhodes et ai., in press). in the last decade, scholars from a variety of disciplines have become interested in the evolution of the mind (e.g., barkow, cosmides, & tooby, ;corballis, ; dennett, ; pinker, , ). a clear consensus has emerged that evolutionary forces have shaped our per- ceptual, communicative, and reasoning systems. the perception of facial attractivenessseems especially likelyto be under selection pressure, given the importance of facial attractiveness in human mate choice (buss & schmitt, ). our results lend preliminary support to this view. references barkow, j. h., cosmides, l., & tooby, j. 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( ). wide- eyed and crooked- faced-determinants of perceived and real honesty across the lifespan. personality & social psychology bulletin, , - . notes i. here and elsewhere, the claim that a particular characteristic is at- tractive should be interpreted in the relative sense of attractiveness vary- ing with the level of that characteristic, rather than in an absolute sense. . although average faces are attractive, they may not be the most at- tractive faces. for example, the most attractive female faces appear to differ systematically from average in some respects, having relatively large eyes, high cheekbones, small jaws and chins, and short nose-to- mouth distances (perrett et al., ). exaggerating these deviations from averageness increases attractiveness further. for some traits, then, extreme values may be preferred to average values (see cronin, , and rhodes, , for discussions of the possible adaptive value of pref- erences for certain extreme traits). . this preference for asymmetric faces was found for the faces of children and young adults, but not for elderly adults. symmetric ver- sions were preferred for elderly faces, apparently because they looked younger. . a follow-up analysis of opposite-sex attractiveness ratings showed the same interaction [f( , ) = . ,p < . ], with the same pattern of means, although the sex difference for perfectly symmetric images (or at any other symmetry level) was not significant by a simple test of main effects. facial symmetry . note that the attractiveness and mate appeal ratings could not have been influenced by making symmetry ratings because symmetry was always rated last, so the results of the anoyas on those variables can- not have been affected by making symmetry ratings. . this forced-choice procedure follows that used in other studies in- vestigating facial attractiveness. for example, kowner ( ) required subjects to make forced choices between natural and perfectly sym- metric versions of faces, and perrett et al. ( ) asked subjects to make forced choices between even more similar pairs of images (composites that differed in the number and selection of component images). . it is possible that making attractiveness and mate appeal judgments for opposite- (but not same-) sex faces contributes to any similarities found for these two tasks. however, comparison of the correlations be- tween attractiveness and mate appeal in experiments i (same raters) and i a (independent raters) suggests that the contribution of any such carryover effects would be quite small. . note that separate proportions (symmetry scores) were calculated for each subject for each cell of the design, so that an anaya on such proportions is quite proper. . note that more than one kind of selection pressure can operate on a given trait or preference (see rhodes, , for further discussion). (manuscript received october , ; revision accepted for publication january , .) inertia, optimism and beauty patrick hawley march , abstract the best arguments for the / answer to the sleeping beauty problem all require that when beauty awakes on monday she should be uncertain what day it is. i argue that this claim should be rejected, thereby clearing the way to accept the / solution. inertia and sleeping beauty if on monday you confidently and rationally believe that slippery slim is guilty, and from monday to tuesday you gain no new relevant evidence, then, quite plausibly, on tuesday you should remain equally confident that slippery slim is guilty. lots of evidence might be relevant: that slim has an impeccable alibi, that the informant who fingered slim is unreliable, that mournful mel has confessed to the crime, that your biases have clouded your judgment, and so on. but if you learn nothing at all relevant to your confident belief that slim is guilty, then surely you should remain confident that slim is guilty. perhaps that was too quick. suppose you lose some relevant evidence— say you forget why you became convinced that slim is guilty— then perhaps you should be- come less confident that he is guilty. or maybe your confidence should change if your cognitive faculties are damaged or disrupted. still, the following principle is intuitively plausible: inertia if you should have degree of belief d that p at time t , and between t and a later time t , your cognitive faculties remain in order, and you neither gain nor lose relevant evidence, then you should also have degree of belief d that p at time t . inertia comes into play in the much discussed sleeping beauty problem. on sunday, sleeping beauty[ ] is informed that after she goes to sleep that evening a fair coin will be tossed. if the coin lands heads, she will be awakened for a moment on monday, put back to sleep, and then not awakened until wednesday morning. if the coin lands tails, beauty will be awakened for a moment on monday, and put back to sleep. while sleeping, her memory of the monday awakening will be erased. then, on tuesday, she will be awakened for a moment, put back to sleep and not awakened until wednesday morning. whether the coin lands heads or tails, on wednesday morning she will be awakened and immediately informed that the experiment is over. when beauty wakes on monday, what should be her degree of belief that the coin lands heads? thirders say / . halfers say / . puzzlingly, there are strong arguments on both sides. a compelling argument for the halfer’s view relies on inertia. when beauty awak- ens on monday she learns nothing relevant to the coin toss. she does learn that she is awake, but surely that news is not relevant to the coin toss. as roger white puts it, “[s]he knew all along that she was to be awakened briefly during the experiment at some time. so it is no news to her when she finds herself awake at an unknown time. when awakened she may learn something that she would express as ‘i am awake now.’ but it is difficult at best to see what bearing this could have for her on whether the coin landed heads.”[ ] moreover, beauty does not forget anything between sunday and monday, and she does not lose evidence in any other way. nor does she suffer any disruption in her cognitive faculties. strange happenings do occur on monday night, if the coin lands tails. but from sunday to monday morning, nothing of the sort occurs. now, since beauty knew that the coin was fair, on sunday she should have degree of belief / that the coin lands heads. (this is an application of david lewis’ principal principle connecting chance to credence.) so, by inertia, when she wakes up she should continue to have degree of belief / that the coin lands heads. thirders[ ][ ][ ][ ][ ][ ][ ][ ] agree with halfers that on sunday beauty should have degree of belief / that the coin lands heads. however, thirders think that beauty’s degree of belief should change to / when she wakes up on monday. the thirder view thus appears incompatible with inertia: beauty’s degree of belief that the coin lands heads should change from sunday to monday, although she suffers no cognitive disruptions, and she neither gains nor loses relevant evidence. despite appearances, few thirders reject inertia. many thirders think beauty gains some relevant evidence upon awakening on monday. some thirders instead (or additionally) hold that, despite appearances, beauty loses relevant evidence. indeed, a thirder can use inertia to argue that beauty gains relevant evidence: since she should change her degree of belief, she does not forget anything (or lose relevant evidence in some other way) and she suffers no cognitive disruption, it follows, given inertia, that she gains relevant evidence. but it is one thing to argue that beauty gains relevant evidence, and quite another to explain how that evidence is relevant. with a satisfactory explanation how that evidence is relevant, thirders might blunt the force of the halfer reasoning, thereby resolving the puzzle. however, no explanation how that evidence is relevant has seen wide acceptance; the sleeping beauty problem still rankles. indeed, as i will discuss, the best developed attempt at such an explanation fails. moreover, as i will explain later, there isn’t good reason to think that beauty loses relevant evidence either. my goal is to resolve the sleeping beauty problem in favor of the halfer view. as i will explain, the best thirder arguments require a common assumption. i will argue e.g. horgan[ ], weintraub[ ], and stalnaker[ ] that we have better reason to reject this assumption than we have to conclude that beauty gains relevant evidence or that she loses relevant evidence (or that inertia is false). once the assumption is rejected, these thirder arguments can be set aside, and the path is open to be a halfer. but before identifying the common assumption, it will be useful to clarify some background issues, and then ask a non-standard question about sleeping beauty’s situation. background i assume that all agree that when beauty wakes up on monday, she should divide her credence among at least some of the following propositions: hm on : the coin lands heads and it is now monday tm on : the coin lands tails and it is now monday tt u e : the coin lands tails and it is now tuesday let p() represent the credences beauty should have when she wakes up on monday, heads be the proposition that the coin lands heads, tails be the proposition that the coin lands tails, mon be the proposition that it is now monday, and tue be the proposition that it is now tuesday. i assume that all agree that: p (hm on ) + p (tm on ) + p (tt u e ) = p (heads) = p (hm on ) p (t ails) = p (tm on ) + p (tt u e ) p (m on ) = p (hm on ) + p (tm on ) p (t u e) = p (tt u e ). an optimistic answer to a different question thirders and halfers disagree about beauty’s degree of belief, on monday morning, that the coin lands heads; thirders and halfers disagree about p (heads). is it / as thirders claim? or / as halfers say? but consider a second question: when beauty wakes up on monday what should be her degree of belief that it is monday? that is, what is p (m on )? little attention has been paid to this second question. it is an unquestioned assumption in the literature on the sleeping beauty problem that when beauty awakes on monday she should be uncertain about what day it is, that is that < p (m on ) < . it is not surprising that this assumption is unquestioned. for imagine yourself in beauty’s shoes as you awake on monday morning. “i have no idea whether it is monday or tuesday!” you might think to yourself. it might seem to you that you have no evidence which indicates that it is now monday as opposed to tuesday. it seems intuitively obvious that you should have at least some uncertainty about the day. however, we should not agree that < p (m on ) < merely on the basis of brute intuition. it is not clear that our intuitions about such a bizarre situation are reliable. we need to rely on reasoning here, not brute intuition. let us question the unquestioned assumption. suppose beauty adopts the following optimistic policy: believe to degree that it is monday whenever awakened during the experiment. if beauty is an optimist, whether the coin lands heads or tails, when awakened on monday she will have full credence in the truth that it is monday. if the coin lands heads, she will never be wrong about the day during the experiment. if the coin lands tails, on tuesday she will also believe to degree that it is monday, and thus have full credence in a falsehood. to explore the plausibility of the optimistic policy, recall her unusual situation: if there are two awakenings, her memory of the monday awakening is erased on monday evening. a straightforward way to understand the memory erasure is this: on monday evening beauty’s belief state is reset to what it was just before she fell asleep on sunday evening. the result of the erasure, i take it, is that for any proposition p, if, on monday, beauty has degree belief d that p, then on tuesday, beauty (if she is awakened) has the same degree of belief d that p. thus, if the coin lands tails, then both on monday and on tuesday beauty has, for example, the same degree of belief that it is monday, and the same degree of belief that the coin lands heads. in short, her degrees of belief are yoked together between monday and tuesday, if she awakens on tuesday. , if the coin lands tails, the yoking of her degrees of belief means that the higher her degree of belief, on monday, in the truth that it is monday, the higher her degree of belief, on tuesday, in the falsehood that it is monday. in a certain sense, being closer to the truth on monday brings the possible cost of being farther from the truth on tuesday. this is an odd situation. beauty is barred from the epistemically desirable goal of both believing to degree that it is monday on monday, and believing to degree that it is monday on tuesday. in this odd situation the best compromise, with respect to the claim that it is monday, might well be to believe to degree that it is monday whenever she awakens. she will be surely be right on monday, and possibly never be wrong about the day during the experiment. indeed this is how elga[ ] describes the memory erasure. if a yoked degree of belief changes while beauty is awake on monday, that degree of belief is to change similarly on tuesday (if she is awakened on tuesday). as the case is sometimes described, beauty’s experiences on monday and tuesday are phenomenally indistinguishable. if she sees a triangular shadow on the wall on monday, she sees a triangular shadow on the wall on tuesday. if she hears a passing airplane on monday, she hears a passing airplane on tuesday. and so on. as several have noted (e.g. kierland and monton[ ], stalnaker[ ] and titelbaum[ ]), the puzzle remains even if her experiences are not phenomenally indistinguishable, as long as the difference between her experiences provide no evidence about propositions of interest— such as propositions about the coin toss or the current day. one can accommodate this observation by yoking together degrees of belief only for propositions of interest as opposed to all propositions. one might attempt to formalize and thereby clarify this thought that optimism is the best compromise by using a scoring rule. however, an initial attempt is inconclusive. according to some scoring rules (for example a linear rule), p (m on ) = , but by other scoring rules (for example brier’s rule) p (m on ) = . it is unclear which rule to apply in this case, and moreover, it is unclear how to calculate the score for beauty’s unusual circumstance. kierland and monton[ ] have approached the sleeping beauty problem by using a scoring rule. they do not reach a single conclusive answer. they use brier’s rule to measure the although suggestive, these thoughts are obviously not sufficient to show that beauty should adopt the optimistic policy. i will later present an argument that p (m on ) = . at the moment, i merely conclude that the claim that p (m on ) = should not be immediately rejected. so let us accept p (m on ) = as temporary working hypothesis. given that hypothesis, we next see what goes wrong with the best thirder arguments. problems with two thirder arguments according to thirders, p (heads) = / . two of the best arguments rely on the key premise (eq) p (hm on ) = p (tm on ) = p (tt u e ). for from (eq) and p (hm on ) + p (tm on ) + p (tt u e ) = it follows that p (hm on ) = / , and given that p (heads) = p (hm on ) it follows that p (heads) = / , the thirder’s conclusion. given the agreed assumptions (in section ), optimism is incompatible with the key premise (eq): if p (m on ) = , then p (hm on ) = p (tm on ) or p (tm on ) = p (tt u e ) (or both). but what, in the eyes of the optimist, is wrong with thirder arguments for (eq)? . elga’s defense of (eq) elga[ ] defends (eq) by arguing both that p (hm on ) = p (tm on ), and that p (tm on ) = p (tt u e ). the optimist need have no quarrel with elga’s argument for the former: sup- expected inaccuracy of beauty’s degree of belief that the coin lands heads. they argue that if expected total inaccuracy is calculated the answer is / , and if expected average inaccuracy is used, the answer is / . they don’t mention that other plausible scoring rules yield yet other answers. by elga[ ], and by arntzenius[ ][ ] and dorr[ ] pose, after awakening on monday, beauty is told that it is monday. at that point her degree of belief that the coin lands heads should be / , for her degree of belief that the coin lands heads should be the same as the chance of the future event that the coin lands heads. (this is another application of the principal principle.) but when she is told that it is monday, beauty should revise her degrees of belief by conditionalization. in particular, her new degree of belief that hm on should be p (hm on /m on ). so p (hm on /m on ) = / , and it follows that p (hm on ) = p (tm on ). the error— from the point of view of the optimist— lies in elga’s defense of the other claim, that p (tm on ) = p (tt u e ). elga reasons like this: suppose when beauty wakes up monday that she is informed that the coin landed tails. she thus learns that either tm on or tt u e is true. since she has no reason to favor tm on over tt u e , or tt u e over tm on , she should divide her credence equally between tt u e and tm on . according to elga, this is an application of a “highly restricted principle of indifference”. since beauty should update her beliefs by conditionalization, after learning that the coin landed tails her credence in tm on ought to be the same as the conditional credence p (tm on|tm on or tt u e ), and her credence in tt u e ought to be the same as the conditional credence p (tt u e|tm on or tt u e ). it follows that p (tm on|tm on or tt u e ) = p (tt u e|tm on or tt u e ), and therefore p (tm on ) = p (tt u e ). the optimist does not accept this reasoning. one of elga’s claims is that beauty should divide her credence equally between tt u e and tm on after learning tails. if so, then beauty’s credence in m on after learning tails should be less than . for if she should divide her credence equally between tt u e and tm on , then her credence in tm on should be less than , and, therefore, her credence in m on should be less than . we assume that, whether the coin toss occurs on monday evening or sunday evening, there is no difference to beauty’s credences. however, elga also claims that after learning tails her credence in tm on ought to be the same as her conditional credence p (tm on|tm on or tt u e ). if so, and if beauty should have degree of belief that it is monday when she awakens, then upon learning tails, beauty’s credence that it is monday ought to remain . so, on pain of accepting that on learning tails beauty should both have degree of belief that it is monday, and have degree of belief lower than that it is monday, the advocate of optimism should not accept both of elga’s claims. it is open to the optimist to reject elga’s view that after learning tails beauty’s credence in tm on ought to be the same as her conditional credence p (tm on|tm on or tt u e ). but this would seem to be an ad hoc departure from standard conditional- ization. a better route for the optimist is to reject elga’s claim that beauty should divide her credence equally between tt u e and tm on after learning tails; the optimist should reject elga’s “highly restricted” indifference principle. . arntzenius and dorr’s argument for (eq) arntzenius and dorr argue for (eq) in a different way. they consider a variation of the original scenario: if the coin lands heads, beauty is awakened on tuesday, but a few moments after the awakening beauty is given an unusual experience which indicates to her that it is tuesday and the coin landed heads. the argument goes that when beauty more formally, the principle, developed and defended in [ ], is that similar centered worlds deserve equal credence. a centered world is a possible world with a designated time and individual. different centered worlds x and y are similar just in case x and y are associated with the same possible world, and the designated individual of x (at the designated time) is in a state subjectively indistinguishable from the designated individual of y (at the designated time). the problem with elga’s defense of the principle, from the perspective of the optimist, is that elga argues, in effect, that if one should have at least some credence both in x and in similar world y, then one should have equal credence in x and y. but to defend the principle it needs to be further shown that if one should have at least some credence in x then one should have at least some credence in any possible world similar to x. however, the optimist thinks that it is rational to have credence in tm on but no credence in the similar tt u e . the optimist would be in good company in rejecting the indifference principle: see [ ] for detailed criticism of elga’s view; stalnaker [p.c.] has different reasons to worry about the application of this principle. is awakened on monday, she should initially divide her credence equally among four possibilities: p ′(hm on ) = p ′(tm on ) = p ′(ht u e ) = p ′(tt u e ). after waiting and failing to have the unusual experience, she is able to rule out ht u e . since she should update her beliefs by conditionalization, her revised credences should be divided equally among the three remaining possibilities: p ′′(hm on ) = p ′′(tm on ) = p ′′(tt u e ). her situation now is relevantly like her situation in the original scenario, so (eq) is true for the original scenario. again the optimist should not accept this reasoning. the optimist might hold that after waiting and failing to have the unusual experience, beauty should not use conditionalization to update her beliefs. but this would seem to be an ad hoc departure from standard conditionalization. a better route for the optimist is to deny that when beauty fails to have the unusual experience she merely learns that ht u e is not true. the optimist may contend that she learns something else, something relevant to what degree of belief she should have that it is monday. she learns that she is in a situation like the original scenario. but, says the optimist, in the original scenario she should have degree of belief that it is monday. thus, when beauty fails to have the unusual experience she learns m on . so, she should not revise her credences by conditionalizing on not-ht u e . she should conditionalize on the strongest proposition learned, m on . another thirder argument michael titelbaum[ ] presents a different argument for the thirder view. titel- baum develops a formal framework for rational belief revision which, unlike the simple bayesian rule of updating by conditionalization, can model cases when a degree of belief changes from an extreme value ( or ) to a non-extreme value. however, we another possibility for the optimist is (like bradley[ ]) to deny that her situation in the revised story is relevantly like her situation in the original story. need not examine the details to note that as titelbaum tells the story, when beauty awakens she is “uncertain whether it is monday or tuesday”. and when he formalizes what he calls the “extrasystematic constraints” of the story, one explicit constraint is that < p (m on ) < . thus, titelbaum simply assumes that p (m on ) = . perhaps titelbaum— or any other thirder— would insist that the claim that < p (m on ) < is simply a stipulation. isn’t one free to stipulate anything one likes? in reply: one can certainly stipulate that beauty has a non-extreme degree of belief that it is monday when she wakes up on monday. but that is not enough for the thirder’s needs. the thirder needs to make the case that beauty should have a non-extreme degree of belief that it is monday. to see why, compare the following case. stipulate that on sunday, confused cal has degree of belief / that cleveland won the pennant. also stipulate that on monday, cal has degree of belief / that cleveland won the pennant, and that between sunday and monday, cal doesn’t lose relevant evidence, doesn’t gain relevant evidence, and his cognitive faculties remain in order. does the case of cal show that inertia is false? clearly not. now revise the case by removing the phrase “doesn’t gain relevant evidence” from the previous paragraph. does the revised case show that, given inertia, cal gains relevant evidence? again, clearly not. cal might gain no relevant evidence, and might have degree of belief / on monday as stipulated, but it might not be that he should have that degree of belief. in order to justifiably conclude that cal gains relevant evidence, an argument is needed curiously titelbaum is unusual in making this assumption explicit. when the sleeping beauty puzzle was introduced to the philosophical literature by elga[ ], the case was described without any mention of beauty’s degrees of belief about the day when she wakes. nor does lewis[ ], one of the earliest halfers, mention any such thing. later, something crept into the presentation of the situation. dorr[ ] says that when she awakes she “will not be able to tell that it is not monday” and then assumes without argument that p (m on ) = . hitchcock[ ] says that when she wakes up she “will not know whether it is monday or tuesday”. but many others, when describing the case, do not explicitly mention anything about beauty being uncertain about the day when she awakes.[ ][ ][ ][ ][ ][ ][ ] that cal should have degree of belief / on monday. merely stipulating that he has degree of belief / is not sufficient. the lesson here applies to beauty. suppose one stipulates that she has degree of belief < that it is monday when she wakes up on monday. and, for the sake of argument, suppose that it then follows (given well accepted principles and the other stipulations about the case) that she has degree of belief / on monday that the coin lands heads. should one conclude by inertia that beauty gains relevant evidence? no. beauty might gain no relevant evidence, and might have degree of belief < that it is monday when she wakes up on monday, but it might not be that she should have that degree of belief. in order to justifiably conclude that beauty gains relevant evidence, an argument is needed that beauty should have degree of belief < that it is monday when she wakes up on monday. merely stipulating that she has degree of belief < is not sufficient. a dutch book let us consider one last thirder argument. some thirders support their view using a diachronic dutch book. although the force of such arguments is debatable, it will be instructive to discuss a recent example offered by draper and pust[ ]. note that draper and pust discuss a slightly different version of the sleeping beauty case. this version is just like the original, except that on monday afternoon beauty is told that it is monday. let us suppose that this additional element does not affect what beauty’s degree of belief should be when she wakes up on monday, or anything else important about the original case. note also that they ensure that the bookie does not have any information that beauty lacks. otherwise the bookie might be able to use that information to his advantage in betting. so the bookie will undergo the same procedure see e.g. christensen[ ] as beauty, sleeping and waking at the same time, as well as memory erasing monday night, if necessary. here is a version of draper and pust’s diachronic dutch book argument: the bookie sells beauty two bets. on sunday the bookie sells her a bet for $ that pays $ if the coin lands tails. beauty considers this fair because on sunday she has degree of belief / that the coin lands tails. beauty and the bookie then go to sleep. on monday afternoon, beauty and the bookie are told that it is monday. beauty revises her belief state. at this point, the bookie sells beauty a bet for $ z that pays $ if the coin lands heads, where z is beauty’s revised degree of belief that the coin lands heads. beauty considers this fair too. if she accepts these bets, then, if z > / , beauty is guaranteed to lose. whether the coin lands heads or tails beauty loses $ − $ z. (if z < / then a different pair of bets will do the trick: on sunday the bookie sells her a bet for $ that pays $ if the coin lands heads. on monday, after beauty and the bookie are told that it is monday, the bookie sells beauty a bet for $ ( − z) that pays $ if the coin lands tails.) thus, if z = / , beauty is vulnerable to a diachronic dutch book. and, we can see, if z = / then beauty comes out even, and thus avoids this dutch book. so, if beauty ought not to be vulnerable to a dutch book, then, after beauty is told that it is monday, she ought to have degree of belief / that the coin lands heads. a further step is needed to reach the thirder view: if p (heads) = / then the dutch book is avoided, and if p (heads) = / then beauty is vulnerable to the dutch book. this further step seems plausible, if we suppose that when beauty learns that it is monday, she updates her belief by conditionalization, that is, if we suppose that z = p (heads|m on ). the thirders we have discussed all hold that p (heads) = p (hm on ) = p (tm on ) = p (tt u e ) = / . so p (m on ) = p (hm on )+p (tm on ) = / , and thus p (heads|m on ) = p (hm on )/p (m on ) = ( / )/( / ) = / . so these thirders avoid the dutch book. the halfer, as defended by david lewis[ ], thinks that p (heads) = p (hm on ) = / , and p (tm on ) = p (tt u e ) = / . so, p (m on ) = p (hm on )+p (tm on ) = / , and p (heads|m on ) = p (hm on )/p (m on ) = ( / )/( / ) = / . so the lewisian halfer faces this dutch book. however, it is not only a thirder who can avoid draper and pust’s dutch book. the optimist halfer avoids it too. according to the optimist halfer, p (heads) = / and p (m on ) = . so p (heads|m on ) = / . , notice that any thirder who accepts that p (heads|m on ) = / must hold that p (m on ) < . for if p (heads|m on ) = / then p (hm on ) = p (tm on ). so, since, p (heads) = p (hm on ) = / , p (m on ) = / . hitchcock[ ] presents a different dutch book argument against the halfer view: on sunday beauty pays $ for a bet that yields $ if tails, and whenever she wakes up she pays $ for a bet that yields $ if heads. if the coin lands heads she loses $ on sunday and gains $ on monday for a net loss of $ . if the coin lands tails she gains $ on sunday and loses $ on both monday and tuesday for a net loss of $ . this argument is criticized by both bradley and leitgeb[ ] and by draper and pust. draper and pust rightly point out that (at least on evidential decision theory) the halfer should not consider the bets offered when she wakes to be fair. that is easy to see in the case of optimist halfer beauty. since optimist halfer beauty is certain that it is monday whenever she wakes, she is certain that if she were to accept the bet today she would accept it tomorrow (if awakened). so she is certain that if she accepts the bet then if the coin lands heads she wins $ , and if the coin lands tails she loses $ both today and tomorrow. that means the expected value of the bet is p (heads) ∗ $ + p (t ails) ∗ (−$ ) = . ∗ $ − . ∗ $ = −$ . since the expected value is less than the bet is not fair. even some causal decision theorists may agree, because ( ) beauty’s activities on monday do in some way causally influence the state of the world on tuesday and ( ) when she wakes beauty is certain that if she were to accept the bet today she would accept it tomorrow (if awakened). one might think that there is a simple diachronic dutch book against the optimist halfer’s view that p (m on ) = because with that degree of belief beauty would bet at any odds that it is monday. an audience member at a conference suggested the following. since beauty is certain that it is monday whenever she wakes, on both monday and tuesday (if awakened) she should be willing to pay $ for a bet that yields $ if it is monday. but then one can guarantee a sure loss by adding another bet on sunday: pay $ for a bet that yields $ if the coin lands tails. whether the coin lands heads or tails beauty is sure to lose. if the coin lands heads she loses $ on the sunday bet and gains $ on the monday bet for a net loss of $ . if the coin lands tails she gains $ on the sunday bet and $ on the monday bet, but loses $ on the tuesday bet, for a net loss of $ . this dutch book argument is problematic for reasons similar to those in the previous footnote. beauty would not accept the bets on monday and tuesday as fair. whenever she awakes, she is certain that it is monday, so she is also certain that if she accepts the bet today she will gain $ . however, she is also certain that, if the coin lands tails, if she accepts today she will accept the same bet tomorrow and lose $ . so, since she has degree of belief . that the coin lands heads, the expected value of this bet is . ∗ $ + . ∗ ($ − $ ) = −$ . the expected value of the bet is less than , so it is not fair (at least according to evidential decision theory and possibly some versions of causal decision theory as well.) an argument for optimism we have now seen the best available arguments for the thirder view, and where, in the optimist’s view, these arguments go wrong. it is now time to argue in favor of optimism. two premises entail that p (m on ) = : ( ) p (heads/m on ) = / ; ( ) p (heads) = / . we have just seen two explicit arguments for ( ), the dutch book argument in the previous section, and the following argument by elga: after beauty is told that it is monday, her degree of belief that the coin lands heads should be / , for her degree of belief that the coin lands heads should be the same as the chance of the future event that the coin lands heads. but when she is told that it is monday, beauty should revise her degrees of belief by conditionalization. in particular, her new degree of belief that heads should be p (heads/m on ). now recall the apparently compelling halfer reasoning in favor of ( ): since beauty knew that the coin was fair, on sunday she should have degree of belief / that the coin lands heads. when beauty awakens on monday she learns nothing relevant to the coin toss. she does learn that she is awake, but surely that news is not relevant to the coin toss. moreover, she has no cognitive mishap between sunday and monday, and does not forget anything or lose relevant evidence in some other way. so, by inertia, when she wakes up she should continue to have degree of belief / that the coin lands heads. optimists conclude from ( ) and ( ) that p (m on ) = . there are strong argu- ments in favor of ( ) and ( ), and ( ) and ( ) together entail p (m on ) = . such is the compelling reasoning for the optimist view that p (m on ) = . thirders disagree. thirders accept ( ) but think p (m on ) < . so thirders would it follows that p (heads) = p (heads/m on ) = p (heads&m on )/p (m on ). but p (heads&m on ) = p (heads). so p (heads) = p (heads)/p (m on ), and thus p (m on ) = . (this reasoning requires that p (m on ) > , but this must be so since p (heads/m on ) = / .) take the optimist argument as a reductio showing that ( ) is false, and conclude there- fore that beauty gains or loses relevant evidence (or both) when she awakes, or else inertia is false. which reasoning should we accept, the optimist’s or the thirder’s? the optimist’s reasoning relies on the premise that beauty neither gains nor loses relevant evidence when she awakes. the conclusion of this reasoning, p (m on ) = , is surprising. thirders, as we have seen, hold that p (m on ) < . thirders conclude, surprisingly, that beauty gains relevant evidence when she awakes, or loses relevant evidence, or, even more surprisingly, that inertia is false. in short: thirders claim that p (m on ) < , and conclude that beauty gains or loses relevant evidence (or conclude, less plausibly, that inertia is false); optimists claim that beauty does not gain or lose relevant evidence, and conclude that p (m on ) = . thirders and optimists both start with an intuitive claim, and reach a counterintuitive conclusion. it is intuitive that p (m on ) < . (wouldn’t beauty wonder what day it is? wouldn’t she learn something if she is told that it is monday?) however it is counterintuitive that on monday she gains or loses evidence relevant to the coin flip. (how can what she learns on monday be relevant to the coin flip? and how can she lose relevant evidence? she doesn’t forget anything or have a cognitive mishap— how can she lose relevant evidence in some other way?) on the other side, it is intuitive that what she learns on monday is not relevant to the coin flip and it is intuitive that she doesn’t lose any evidence– much less lose evidence relevant to the coin flip. but it is counterintuitive that p (m on ) = . as far as intuitions go, the optimist’s reasoning and the thirder’s reasoning are on a par, with intuitive premises and a counterintuitive conclusion. moreover the optimist and the thirder accept the same principles: belief revision by simple conditionalization, the principal principle, and (at least most thirders anyway) inertia. thus, as far as intuitions and principles go, the optimist argument is at least as persuasive as any thirder argument we have seen. in itself that is an interesting conclusion— until now the optimist view has been rejected by all without discussion. indeed, further consideration tips the balance in favor of the optimist’s argument. notwithstanding numerous thirder arguments, convincing to many, the sleeping beauty problem continues to rankle. despite the thirder arguments, it is still difficult to believe that beauty learns something relevant to the coin flip when she awakes on monday. beauty learns that she is awake, but she already knew on sunday that she would learn that. what does she learn that is relevant to the coin flip? moreover, it is difficult to believe that beauty loses evidence relevant to the coin flip. she does not forgot anything between sunday and monday. she suffers no cognitive mishaps. what evidence does she lose and how does she lose it? it does not look promising to claim that beauty gains or loses relevant evidence. even so, some thirders do claim so and attempt to explain how it is that beauty gains or loses relevant evidence. let us next explore the most serious of such attempts. they are, as we will see, unsuccessful. . does beauty gain relevant evidence when she awakes? the most developed attempt to explain how beauty learns something relevant to the coin flip is due to horgan.[ ][ ] according to horgan, beauty learns “i was awakened today by the experimenters”, and this information is relevant to the coin flip. horgan tries to isolate the effect of what beauty learns by partitioning the current information that she has on monday after being awakened. when beauty wakes up on monday, she first assigns preliminary probabilities relative to a portion of her current information. this portion of her current information excludes the information that she was awakened today by the experimenters and also excludes the information that she is awake right now. the portion includes the information about the situation that beauty had on sunday and continues to have on monday, and also includes the information that today is either monday or tuesday.[ , ] according to horgan, hm on , tm on , ht u e and tt u e are all consistent with and equally well supported by that portion of her current information. since, he argues, these four possibilities are mutually exclusive and exhaustive, the preliminary probabilities should be: p−(hm on ) = p−(tm on ) = p−(ht u e ) = p−(tt u e ) = / . and thus the preliminary probability of heads is p−(hm on ) + p−(ht u e ) = / . next, according to horgan, beauty should update her preliminary probabilities by conditionalization on the information that she has been awakened today. that information (together with what she knows about the experiment) rules out ht u e . conditionalizing on this information yields: p (hm on ) = p (tm on ) = p (tt u e ) = / , and so p (heads) = p (hm on ) = / . on this view, what beauty learns when she wakes is relevant to the coin flip because it lowers the preliminary probability / of heads to the updated probability / . it is unclear to me whether this two-stage framework is a generalization of standard bayesian conditionalization (as horgan suggests) or is instead a departure from it. but let us accept the framework for the sake of argument. even so, the proposal fails. a minor addition to the sleeping beauty story will help show why. suppose that on sunday a poster advertising a performance of the ballet sleeping beauty is hanging on the door outside beauty’s room in the experimental laboratory. the poster will remain on the door at least until monday evening. the poster cannot be seen by beauty from inside the room. if the coin lands tails, the poster remains on the door throughout the experiment. however, if the coin lands heads, the poster is removed on monday evening at midnight while beauty is sleeping, and then returned to its place twenty-four hours later, as beauty continues to sleep. beauty is certain of all of this. on sunday, before she enters the room, she sees the poster on the door and she is certain that the poster is on the door. throughout the experiment she will continue to be certain that the poster is on the door. note that the addition of the poster does not matter for any of the thirder arguments discussed earlier. in horgan’s framework, beauty’s preliminary probabilities on monday are deter- mined relative to a portion of her current information which includes the information about the situation that beauty had on sunday and continues to have on monday, and also includes the information that today is either monday or tuesday. two pieces of information that beauty has on sunday and continues to have on monday are: (a) the poster is on the door, and (b) on tuesday, if the coin lands heads, the poster is not on the door. from this information, it follows that ht u e is ruled out, and therefore the preliminary probability of ht u e is . that means that what beauty learns when she wakes is not relevant to heads; updating her preliminary probabilities by con- ditionalization on the information that she has been awakened today has no effect on the probability of hm on and thus no effect on the probability of heads. horgan may respond by excluding the information that the poster is on the door from the portion of her information used to calculate her preliminary probabilities. but that response does not work. a second response is to hold that while poster for example, if the arguments mentioned for the thirder premise that p (heads/m on ) = / work for the original story, they work for the poster version. being certain that the poster is on the door doesn’t change whether beauty is subject to draper and pust’s diachronic dutch book. being certain that the poster is on the door doesn’t affect elga’s reasoning based on the claim that if, on monday, beauty learns that it is monday, she ought to have degree of belief / that the coin lands heads. to see why, consider the effort of pust[ ], who also argues against horgan that beauty’s preliminary probability in ht u e is . pust relies on the claim that it is not possible for beauty to be in an epistemic situation in which she lacks the information that she is presently conscious. horgan’s reply, in effect, is to exclude her information that she is presently conscious from the portion of her current information used to determine her preliminary probabilities. horgan imagines beauty saying to herself on monday, “statements hm on , ht u e , tm on , and tt u e are all consistent with the conjunction of ( ) the information i had on sunday and with ( ) the information that today is either monday or tuesday. in particular, statement ht u e is consistent with that specific information—notwithstanding the fact that if ht u e were true, then today i would not be conscious. so, relative to the information just mentioned, and only that information, the four statements each have the same degree of evidential support.”[ ] (the names of the possibilities are changed to match the present paper.) horgan does not explicitly say why he excludes beauty’s information that she is presently conscious. presumably he thinks that beauty’s (monday) information that she is presently conscious is not information that she had on sunday. or perhaps he thinks that the information that beauty is presently conscious should be excluded because that information (given the description of the case) entails that she has been awakened today, and the information that she has been awakened today is already excluded. either way, horgan has no such grounds to exclude the information that the poster is on the door. beauty has and continues to have the information that the poster is on the door from sunday to beauty does not gain any relevant information, standard beauty does. but that second response is inadequate too: it would leave a thirder about poster beauty with no explanation why her degree of belief in heads should change, and it would leave a halfer about poster beauty with the challenge of explaining why the addition of the poster should make a difference to beauty’s degree of belief in heads, when that addition does not affect the force of the thirder arguments discussed earlier. horgan’s proposal aside, the poster case highlights a challenge facing any attempt to show that when she learns that she is awake she gains information relevant to heads. in the poster version beauty is certain that the poster is on the door and she remains certain that the poster is on the door throughout the experiment. similarly, it seems, in the standard version, not only is she certain, on sunday, that “today is tuesday and the coin lands heads” is false, throughout the experiment she remains certain that this sentence is false. but on monday, certainty that “today is tuesday and the coin lands heads” is false is sufficient to rule out ht u e . so the information that she is awake is not needed to rule out ht u e . but then how could learning that she is awake be in any way relevant to heads? monday, and that information does not entail that she has been awakened today– the poster is also on the door on monday while she is sleeping before being awakened. in essence, the problem for horgan’s view is that on sunday beauty already had information which, on monday, suffices to rule out ht u e ; on monday she can rule out ht u e without using the information that she has been awakened today. someone might suggest that the information conveyed on sunday using “the poster is on the door” differs from the information conveyed on monday using “the poster is on the door”: the former describes the location of the poster on sunday and the latter describes the location of the poster on monday. but this suggestion does not help horgan. beauty has the information that the poster is on the door throughout the experiment, even if the nature of this information changes over time. we can put it this way: throughout the experiment she will remain certain that the sentence “the poster is on the door” is true even if the information conveyed by a use of this sentence changes over time. note that she may need to be awake in order to fix the reference of the indexical “today” or the present tense “the poster is on the door” and thus she may need to be awake on monday in order to eliminate ht u e on monday. but that does not mean that she needs to use the information that she has been awakened (or that she is awake) to eliminate ht u e . she may need to be awake in order to fix the reference of an indexical like “today” in “today is tuesday and the coin lands heads”, but that does not mean that she needs to use the information that she is awake in order to fix the reference of “today” or to eliminate ht u e . . does beauty lose relevant evidence when she awakes? thus, the best developed attempt to show that beauty gains relevant evidence does not succeed. the thirder might instead pursue another option: beauty loses relevant evidence. this approach is not promising either. between sunday and monday, beauty does not forget anything, and she suffers no cognitive mishaps. unless there is some other way to lose evidence, beauty does not lose any. perhaps there is another way to lose evidence. the shangri-la example (due to arntzenius[ ]) has been thought by some to show how: you will travel to shangri-la by one of two paths, the path by the mountain or the path by the sea. which path you take is determined by the flip of a fair coin. if the coin lands heads you travel on the path by the mountain; if the coin lands tails you travel on the path by the sea. however, the guardians of shangri-la have arranged it so that if the coin lands tails and you travel via the sea, you don’t remember doing so: when you pass through the gates of shangri-la, your memories of traveling by the sea are wiped out, and replaced by apparent memories of having traveled through the mountains. on the other hand, if the coin lands heads and you go via the mountains, nothing untoward happens and you enter the city with your memories intact. before you set off, all the arrangements are known with certainty by you. before the coin is flipped, according to the principal principle, you should have degree of belief / that the coin lands heads. now suppose the coin lands heads and you travel by the mountains. as you are traveling, we can agree, you should be certain that the coin landed heads because you see the enjoyable mountain scene. then, according to arntzenius, after entering shangri-la your degree of belief that the coin landed heads should be / again: “... once you have arrived, you will revert to having degree of belief / in heads. for you will know that you would have had the memories that you have either way, and hence you know that the only relevant the two options do not exclude each other; the thirder might claim that beauty both gains and loses relevant evidence. but if beauty does not gain relevant evidence she does not both gain and lose relevant evidence. information that you have is that the coin was fair.”[ ][p ] if this is right, then if the coin lands heads you might be said to lose information upon passing through the gates of the city. just before the gates you are certain that the coin landed heads and you are certain that you traveled through the mountains. after passing through the gates you are no longer certain of these things. this loss of certainty, one might say, is (or indicates) a loss of information. but you do not forget anything and you do not suffer any cognitive mishaps. apparently then there is different a way to lose information- a way different from forgetting or suffering a cognitive mishap. the mere threat of being in the counterfactual situation where the coin lands tails and forgetting/disruption occurs seems to be enough to bring about this loss. perhaps beauty loses information in some such way; perhaps the threat of the possible memory erasure monday evening is enough to bring about a loss of information about what day it is. however, the shangri-la case does not show how to lose information in a way dif- ferent from forgetting or cognitive mishap. arntzenius claims that, if the coin lands heads, after passing through the gate you should change from degree of belief to degree of belief / that the coin landed heads. but this claim is incompatible with the bayesian principle that belief updating (for non-indexical propositions) should only occur by conditionalization. given that principle, after passing through the gate you should continue to have credence that the coin landed heads. for once you have credence that the coin landed heads, your credence cannot be lowered by condition- alization. indeed, intuitively, the principle yields the correct result in this case. why should you reduce your credence in the truth that the coin landed heads because an unfortunate event would have occurred if the coin had instead landed tails? on the other hand, there is some intuitive appeal to the view that your degree of although arntzenius says you will revert to degree of belief / , i take it that he also holds that you should revert to degree of belief / . belief should revert to / after passing through the gates. (imagine yourself in that situation. wouldn’t you doubt whether your memories are accurate?) but principled commitment to bayesian principles should not stand or fall on the basis of mere in- tuitive appeal— especially given the countervailing intuition that you should not give up your certainty in the truth that the coin landed heads because something untoward would have happened to you if the things had been different. arntzenius is of course aware that his view of the shangri-la case conflicts with standard bayesian principles. however mere intuition is not the justification he gives for his view. there you are before the gates. the coin landed heads and you are certain that it did. then you pass through the gates. arntzenius’s suggestion seems to be that you should now ignore your evidence that the coin landed heads because you know that you would have had the same evidence whether the coin landed heads or the coin landed tails. but this way of reasoning is suspicious at best. compare the following. you are, i take it, certain that you are awake right now. but suppose you start thinking about what it is like when you are dreaming and you realize that you would have had the same evidence whether you are awake or you are asleep having a particularly vivid dream. at that point, should you then ignore your evidence that you are awake? no. surely it would be a mistake at that point to ignore your evidence that you are awake. for you are certain that you are not asleep; you are certain that you are not in the counterfactual situation where you are asleep having a particularly vivid dream. learning the interesting fact that you would have had the same evidence in a certain counterfactual situation should not bring you to stop being certain that that situation is counterfactual. this is the best sense i can make of the remark quoted earlier: “ ... you will know that you would have had the memories that you have either way, and hence you know that the only relevant information that you have is that the coin was fair.” the point here is simply that you should not, on the basis of discovering that you would have had the same evidence if you were dreaming, accept the conclusion that you should ignore your evidence that you are awake. we can save the problem of explaining what exactly is wrong with this reasoning for later. here is another example of similar suspicious reasoning: the wall is painted red, and on monday morning you one can say something similar about shangri-la. at the gates of shangri-la, after the coin landed heads, you are certain that the coin landed heads, and you are certain that you are not in the counterfactual situation where the coin landed tails. then you pass through the gates. on the other side of the gates, you learn an interesting fact about the counterfactual situation in which the coin landed tails. you learn that the evidence you have at that point is the same (or at least appears the same) as the evidence you would have had in the counterfactual situation in which the coin landed tails. you should not then ignore your evidence that the coin landed heads. for you are certain that you are not in the counterfactual situation in which coin landed tails. you have merely learned an interesting fact about that counterfactual situation. neither mere intuition nor arntzenius’ suspicious reasoning should sway us from principle: when the coin lands heads, you should continue to be certain that the coin landed heads after passing through the gates of shangri-la. thus the shangri-la case does not provide good reason to think there is a way to lose evidence different from forgetting or suffering a cognitive mishap. so that case provides no good reason to think that beauty loses evidence. are certain that it is painted red. as you know, in a nearby room there is a white wall with a red light shining on it, but you are certain that you are not in that nearby room. it would be a mistake to ignore your evidence that the wall is painted red, even if you come to know on monday evening that you would have had the same evidence whether you are in the red painted room or the red lighted room. for you are certain that you are not in the nearby room. your certainty should not be shaken by the discovery of the interesting fact that you would have had the same evidence in some counterfactual situation. perhaps behind arntzenius’s reasoning is a principle like this: if you have the same evidence that p in situation s as you have in situation s’, then you should have the same degree of belief that p in situation s and situation s’. even if this principle is correct, it is not sufficient to show that you should have degree of belief / that the coin lands heads after passing through the gates. it is compatible with this principle that you have degree of belief that the coin lands heads after passing through the gates whether the coin lands heads or tails. as far as i know this view of the shangri-la case has not yet found a defender in print— although wolfgang schwarz apparently advocated it in a talk. . on the optimist side earlier, we saw that as far as intuition and principles go, the reasoning of optimists and the reasoning of thirders are on a par. thirders and optimists both start with an intu- itive claim, and reach a counterintuitive conclusion. thirders claim that p (m on ) < , and conclude that beauty gains or loses relevant evidence (or conclude, less plausibly, that inertia is false); optimists claim that beauty does not gain or lose relevant evi- dence, and conclude that p (m on ) = . the last section investigated the most plausible attempt to show how beauty can lose relevant evidence. the section before last examined the most developed attempt to show that beauty gains relevant evidence. we found no good reason to believe that beauty either gains or loses relevant evidence. this strongly supports the optimist’s claim that beauty does not gain or lose relevant evidence, given the lack of any better proposals to explain how beauty can gain or lose relevant evidence. these considera- tions thus tip the balance in favor of the optimist’s argument over the thirder’s. one should follow the argument where it leads, and conclude that p (m on ) = . however, there is a lingering issue. the optimist’s conclusion, p (m on ) = , is not easy to believe. when one imagines oneself in beauty’s position upon awakening on monday, one imagines that one would feel uncertain about what day it is. it is easy to think that beauty should be uncertain about what day it is when she awakes on monday. however, the optimist can help make the claim that p (m on ) = easier to accept. the optimist can explain why one might mistakenly believe that p (m on ) < . the explanation is that one is attracted to something like the following thought: because of the memory erasure, beauty cannot distinguish monday wakings from tuesday wakings. when she awakes on monday, she has no evidence that indicates to her that it is monday as opposed to tuesday. so, on monday, surely she should give at least some credence to the proposition that it is now tuesday. it is understandable that this sort of thought might lead one to believe that p (m on ) < . but, again, there is a striking similarity to a skeptical thought: i cannot distinguish an experience had while awake from particularly vivid dream experiences had while asleep; i have no evidence that indicates to me that i am awake now as opposed to being asleep having one of those particularly vivid dreams. so surely i should give at least some credence to the proposition that i am asleep right now. it is understandable that this sort of thought might lead me to uncertainty whether i am awake now. many have been attracted to skeptical thoughts. however, while attractive, the skeptical thought is mistaken. i am certain that i am awake right now, and surely it is rational for me to be certain that i am awake right now. despite recognizing that the thought is mistaken (we can figure out why another day) the skeptical thought retains an illusory air of cogency. similarly, says the optimist, the thought about beauty is mistaken. on monday, beauty should be certain that it is monday. but, as in the skeptical case, even after recognizing that the thought is mistake, the illusory air of cogency persists. conclusion i have considered the best thirder arguments i am aware of: by elga, by arntzenius and dorr, by titelbaum, and by draper and pust. i have explained how these arguments each require that p (m on ) < . therefore, if p (m on ) = , these arguments should is there is a quick way to show that although the skeptical thought is mistaken the thought about beauty is not mistaken? one might say that although i have overwhelming evidence that i am awake now, beauty (on monday) does not have overwhelming evidence that it is monday. but this suggestion fails. on monday, beauty does have overwhelming evidence that it is monday– she is filled with memories of the happenings on sunday, memories, as she would put it, about “yesterday”. one might reply that she does not have overwhelming evidence that it is monday because ( ) she should doubt that her memory is reliable because if it is tuesday she would have indistinguishable (apparent) memories, and ( ) doubt about the reliability of her memory undermines or defeats her evidence that today is monday. but then parallel points would seem to apply to the dreaming case: i do not have overwhelming evidence that i am awake because ( ) i should doubt that my experiences reliably indicate that i am awake because if i am asleep i would have indistinguishable experiences, and ( ) doubt about the reliability of my experience undermines or defeats my evidence that i am awake. not be accepted. i have also argued that p (m on ) = . thus, the thirder arguments should not be accepted. the path is clear to be a halfer. references [ ] f. arntzenius. reflections on sleeping beauty. analysis, ( ): – , . 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[ ] r. white. the generalized sleeping beauty problem: a challenge for thirders. analysis, ( ): – , . workingp.pdf “one, two, (three), infinity: newspaper and lab beauty-contest experiments” by rosemarie nagel, antoni bosch-domènech, albert satorra, and jose garcía-montalvo universitat pompeu fabra, barcelona november , acknowledgments: we wish to thank ernan haruvy for his comments on a preliminary version. we acknowledge financial support from the spanish ministry of education through grants sec - -ce and dges pb - , and the eu-tmr research network endear (fmrx-ct - ). we thank the spanish newspaper expansión and the german magazine spektrum der wissenschaft for letting us use their platforms to run our experiments, richard thaler for giving us his data from the financial times experiment, and gary charness, sjaak hurkens and bettina rockenbach, for running an experiment in their classes. abstract “beauty-contest” is a game in which participants have to choose, typically, a number in [ , ], the winner being the person whose number is closest to a proportion of the average of all chosen numbers. we describe and analyze beauty-contest experiments run in newspapers in uk, spain, and germany and find stable patterns of behavior across them, despite the uncontrollability of these experiments. these results are then compared with lab experiments involving undergraduates and game theorists as subjects, in what must be one of the largest empirical corroborations of interactive behavior ever tried. we claim that all observed behavior, across a wide variety of treatments and subject pools, can be interpreted as iterative reasoning. level- reasoning, level- reasoning and level- reasoning are commonly observed in all the samples, while the equilibrium choice (level-maximum reasoning) is only prominently chosen by newspaper readers and theorists. the results show the empirical power of experiments run with large subject-pools, and open the door for more experimental work performed on the rich platform offered by newspapers and magazines. j.e.l. classification codes: c , c keywords: experiments, bounded rationality, beauty-contest, parallelism . introduction in june , richard thaler on one hand, and antoni bosch-domènech and rosemarie nagel on the other, totally unaware of each other endeavor, designed and announced an experiment on the beauty-contest game in two different business daily newspapers, in the uk and spain, inviting the readers to participate. five months later, reinhard selten and rosemarie nagel ( ) replicated the experiment in a german scientific magazine. when designing an experiment, many elements are taken into account that can influence its results. just to mention a few: ) physical environment, ) subject pool (gender, education and training, group identification and friendship, etc.), ) number of subjects, ) communication among subjects, ) information available to subjects, etc. each represents a potential treatment or control. when experimenting with newspaper or magazine readers (i.e., announcing an experiment in a daily newspaper and inviting its readers to participate in it) the experimenter looses control simultaneously of all these elements. in addition, two other elements that play a crucial role in any experimental design can be changed dramatically: ) reward, ) duration of the experiment. however, running experiments in a newspaper helps to answer questions like the following. are the results of lab experiments different from those obtained with large numbers of subjects, who are not the usual students, have plenty of time to ponder their decisions, and can obtain large prizes? to say it differently, by running experiments in newspapers we put to the test the critical assumption of “parallelism” between the lab and the field. also, experimenting in newspapers has advantages. they are cheap, since sponsors usually finance prizes. they do not require having a lab or easy access to students. they allow for a variety of subject pools in terms of interests, knowledge and nationalities, each pool corresponding to the particular readership of each newspaper. and potentially, they have a huge educational impact on the public at large, being advertised, described, and analyzed in the mass media. the basic elements of a typical experiment are the following: it usually consists of a relatively small group of persons (up to subjects), who arrive at the lab at the same time, participate in an experiment for or hours, and are paid slightly above the equivalent to the minimum salary per hour. a number of experiments tried to go beyond the basic procedure of experimenting. the iowa electronic markets may be the best known of them. the advent of internet has allowed some experimenters to move out of the lab. bossaerts and plott ( ), for instance, have run several experiments using the internet as a medium to collect experimental data, subjects being able to lock in any time they want within a range of several days. lucking- reiley ( ) and list and lucking-reiley ( ) test different auction mechanisms selling sports-cards in a real market or on the internet. see also isaac et al ( ) about the difficulties of large-scale experiments. for a pre-internet experiment involving hundreds of subjects, bohm ( ) is a classic example. economists have always questioned whether subjects other than students behave differently in a given setting. for example, cooper et al. ( ) study behavior in ratchet effect games with students, experienced managers, and white-collar workers from china. the main difference observed is that managers behave differently in games with real world content and with abstract content. students act the same in both contexts. cross-cultural studies have become fashionable after the work of roth et al ( ). yet, we are not aware of any experiment run in newspapers or magazines. these are experiments not involving students, with numbers of subjects (drawn possibly from different cultures) in the thousands, time availability extended to several weeks or months, and with rewards beyond the usual financial constraints. in a more fundamental sense, these are experiments with much less control, in a zone between a fully controlled experiment and a survey. in this paper we first compare three newspaper experiments of the beauty-contest game. ) the experiment run in the financial times (ft from now on) by richard thaler ( ). ) the experiment run in expansión (e from now on) -a spanish daily business newspaper similar to financial times- by antoni bosch-domènech and rosemarie nagel ( a, b, c). and ) the experiment run in spektrum der wissenchaft (s from now on) -a monthly german science magazine, the german edition of scientific american- by reinhard selten and rosemarie nagel ( ). we also comment on some methodological points that arise when experiments are proposed to newspaper and magazine readers. second, we relate these experiments to similar ones run in labs, as reported in nagel ( ), and to new experimental data involving students, economists and game theorists as subjects. third, an essential feature of the present paper is the integration of the statistical analysis of these independent experiments -involving widely different subject pools, sample sizes, payoffs and settings- in a single statistical model. this model enables to capture aspects of the individual decisions that fit the predictions of a particular game-theoretical model, the model of iterated best reply, as discussed in nagel ( , ), stahl ( ) and ho et al. ( ). the paper is organized as follows: in section we explain the game and its theoretical predictions. section contains the design of the newspaper experiments. in section we report the results of these experiments. in section we compare the lab experiments with the newspaper experiments. in section we describe the statistical methods applied to further the comparison. section gives the results of the statistical analysis and section concludes. . the game a basic beauty-contest game is as follows. a certain number of players each chooses simultaneously a decimal number, let us say, from the interval [ , ]. the winner is the person whose number is closest to p times the mean of all chosen numbers, where p < is a predetermined and known number. the winner gains a fixed prize. if there is a tie, the prize is split amongst those who tie or a random draw decides the winner. the game is dominance solvable. the process of iterated elimination of weakly dominated strategies leads to the game's unique equilibrium in which everybody chooses . thus, a rational player does not simply choose a random number or his favorite number, nor does he choose a number above p, since it is dominated by p. moreover, if he believes that the other participants are rational as well, he will not pick a number above p ; and if he believes that the others are rational and that they also believe that all are rational, he will not pick a number above p and so on, until all numbers are eliminated but zero. the concept of iterated dominance is an important concept in game theory. the beauty-contest game is an ideal tool to study whether individuals reason in steps and how many iterated levels subjects actually apply. game theory has mostly developed using deductive and refinement concepts. however, their scarce predictive power in some experiments has turned the attention to alternative approaches based on bounded rationality and heterogeneity of beliefs. obviously, once individuals are assumed not to be fully rational or to be diverse in their beliefs, selection of equilibria becomes an empirical matter (see, e.g., schelling ( ), stahl and wilson ( ), costa-gomes et al. ( )). for the beauty-contest experiments, nagel ( ), stahl ( ) and ho et al. ( ), show that a model of iterated best reply describes subjects behavior better than the equilibrium obtained by iterated elimination of dominated strategies. they classify subjects according to the number of steps, or depth, of their reasoning. accordingly, a level- player chooses arbitrarily in the given interval, with the mean being . a level- player gives best reply to level- players and thus chooses · / = . . a level- player chooses ·( / ) and so on. a player, who takes infinite steps and believes that all players take infinite steps, will choose the equilibrium . the number of steps is infinite. when subjects choose in [ , ] (as in e), a finite number of reasoning steps leads to the equilibrium. if only integers are allowed (as in f) there are several equilibria. in the case of p = / , there is an additional equilibrium to “all choosing ,” which is “all choosing .” this is a minor modification that should not change the game in an important way. however, if p had been equal to . , the equilibria would have been “all choosing either , , , , or ,” instead of just a unique equilibrium as in the case of real number choices (see lópez ( )). the hypothesis of iterated levels of reasoning predicts that choices will be clustered around the values . , . , . , . , … and . . newspapers’ experiments . design participants in the newspapers’ experiments are asked to choose a decimal number in [ , ] (in [ , ] in e, non-negative integers only in ft). the winner is the person who chooses the number closest to / of the average number submitted. rewards offered and time available in the newspapers’ experiments were much larger than rewards offered and time available in the lab as can be seen in table . thaler ( ) and bosch-domènech and nagel ( a) wrote the instructions without knowing about each other’s plan of running a newspaper experiment. selten and nagel ( ) had both sets of e and ft instructions when writing their sets of rules for s. table summarizes common aspects and differences between the three games run. the newspapers’ editors imposed some of the differences in the instructions. thaler had to limit the choices to integers instead of decimal numbers. the reason was a legal restriction imposed by the lawyer of ft. the lawyer thought that a game with decimal numbers becomes a game of pure luck, and gambles by private persons or institutions are not allowed in the uk. this restriction causes a higher number of ties. in order to decide the winner in ft’s contest, “the judges consider the best answer to be the tie breaker.” for a survey on the beauty-contest experiments, see nagel ( ). all data sets used in this paper are available upon request. items financial times expansión spektrum numbers/ interval to choose from integer number in [ , ] number in [ , ] number in [ , ] explanation of “ / of the mean” with an example: people choose , , , , . the average is , / of which is . the person who chooses wins with a definition: suppose persons participate. sum the chosen numbers and divide them by . multiply the results by / . the winning number is the closest to this result no explanation of mean or / of mean is given. / of mean is called “target number” comments asked “please describe in no more than words the thought processes you went through in arriving at your number” “if you want to add some comment about how you decided to choose your number, we are interested in it” “we will be glad when you also tell us how you got to your number” prize return club class tickets to new york or chicago donated by british airways . pesetas (about $ ), paid by expansión dm (about $ ) paid by spektrum announceme nt of the rules once pre-announcements of publication of the game; appearance of rules on consecutive days once time to submit days week weeks submission form postcards letters, fax, or e-mail letters or e-mail other restrictions one entry per household, minimum age , resident of uk; excluded: employees of ft or close relatives, any agency or person associated with the competition one entry per person. personnel of universitat pompeu fabra and direct family excluded one entry per participant. employees of spektrum excluded cover story, context of experiment competition as “appetizer for the ft mastering finance series”... “contest will be discussed … in an article on behavioral finance…. the series will offer a mix of theory and practical wisdom on … corporate finance, financial markets and investment management topics” this is an exercise, an experiment ... related to economics and human behavior. john maynard keynes could say that playing at the stock market is similar to participating in a beauty-contest game “who is the fairest of them all? the average... according to psychological tests. however, sometimes it helps being different from the average by the right amount.” tale about a country hairia where the most beautiful person is the one who has / of the hair-length of all contestants. cover story, context of experiment competition as “appetizer for the ft mastering finance series”... “contest will be discussed … in an article on behavioral finance…. the series will offer a mix of theory and practical wisdom on … corporate finance, financial markets and investment management topics” “this is an exercise, an experiment ... related to economics and human behavior. john maynard keynes could say that playing at the stock market is similar to participating in a beauty-contest game…” “who is the fairest of them all? the average... according to psychological tests. however, sometimes it helps being different from the average by the right amount.” tale about a country hairia where the most beautiful person is the one who has / of the hair-length of all contestants language english spanish german description of newspaper/ magazine daily business paper, world wide distribution, printed in england, with , copies per day. daily business paper, distributed in spain with , copies per day. monthly magazine, german edition of scientific american, distributed in germany, with about , copies per month. authors thaler bosch, nagel selten, nagel table . main features of the newspapers’ experiments expansión requested that the opening article included a reasoned justification for performing the experiment. this newspaper did also several pre-announcements of the game, days before the opening article appeared. furthermore, without the authors’ knowledge, expansión published a shortened version of the opening article containing the rules of the game on the three consecutive days following its publication. the shorting resulted in the omission that comments were welcome and that only one number per person would be accepted. in fact, several participants submitted multiple numbers. however, they only amounted to about % of the entries. finally, spektrum der wissenschaften asked selten and nagel to write a fairy tale, introducing the spirit of the game. the editor changed the story submitted of a nose-length beauty-contest to a hair-length beauty-contest. these reported interventions on the part of the newspapers’ editors are examples of how experimenters who use the mass media as a platform for their experiments may be constrained in ways that they do not face in the lab. fortunately, we believe that none of the described interventions had a significant influence on the results. but other differences in the design of the experiments, imposed or not by the newspapers’ editors, may have had an impact on the results and are worth reporting here. ) only entrants in the ft experiment were forced to explain their decision . it is well known among experimentalists that requiring subjects to provide explanations may force them to think the decisions over, bringing about more thoughtful results. however, in e, the average choice of those entries, which submitted comments was . , whereas the average choice of entries without comments was . . ) we know from lab experiments that giving examples can tip decisions. in ft, an example was provided with the number as the winner. it is not farfetched to ponder whether using an example that focuses on low numbers did not push entrants towards small ones. indeed, in the ft lawyer believed that if subjects had to make a comment showing their skills in choosing a number, this could be used in court to prove that the game was not a gamble. ft, numbers above were much less frequent than in the other two publications. in addition, as teachers we know that examples are good didactic devices. thus, giving an example may also have helped to educate entrants about the game. ) the number of participants was a parameter that was not directly controlled by the experimenters, but was certainly conditioned by the design. in e, in spite of having half the time to answer compared to ft and s, the number of participants was the largest of all. one reason was the fact that the game was prominently announced in e, where an advertisement on the first page was run for several days. another reason might have been allowing fax and e-mail entries in e, unlike ft which only accepted mailed letters. ) we all very well know that using e-mail requires little effort. this may have enticed the participation of people who did not want to spare one moment to think about the game (“noise players” if you want). forbidding the use of e-mail and forcing entrants to sit down to write their decision on a piece of paper, put it inside an envelope, place a stamp on it, and post it, could also have had an “educational” effect. however, a comparison of the numbers submitted by mail or by e-mail does not show significant differences. ) communication among subjects could not be constrained. in the results section we will report on some of the consequences of this loss of control, for example, as observed collusion among some participants. . . results figures to show the relative frequencies of the numbers chosen (the rounding to an integer is from to . , . to . , etc.) in the three newspapers’ experiments. the figures also indicate the number of participants, the average of all numbers and the number submitted by the winner. in total there were participants ( , in e, , in ft and , in s). we will show that when we exclude numbers above , the distributions of numbers in ft and s are strikingly similar. which, incidentally, may help to explain the higher numbers of s and s in ft than in e. the results seem to confirm the existence of a common pattern of decision-making among participants, previously identified in lab experiments of the beauty-contest game and interpreted as steps of iterated dominance (see references above): the most popular numbers in all three experiments are two-thirds of (about ), two thirds of this number (about ) and the equilibria of the game ( and in ft, in e and in s). the steps of iterated dominance interpretation claims that in the beauty-contest game people reason in steps. step , which would be the preliminary step of any reasoning, translates into numbers that are arbitrarily distributed over the interval, resulting in an expected value of ( . if numbers are from to ). level- reasoning is ( / )· = . . level- reasoning is ( / )· . = . and so on. taking this reasoning to all its steps of iterated dominance would lead to choose the nash equilibrium . we report this finding as: fact : the numbers obtained by the process of reasoning in steps coincide with the peaks observed in the experiments. this is particular true of the first two steps and the maximum step (and to some extent of the third as well). from the submitted numbers it should be possible to identify those entrants that take one reasoning step, those taking two steps, perhaps even those taking three steps, and those taking all the steps down to the nash equilibrium. this will be done in sections and , using statistical techniques. between the equilibrium choice and step or there are no other notable peaks and in the comments submitted we could not find anybody who stopped at just steps of reasoning. therefore we infer the following additional fact. as mentioned in our footnote , when subjects have to choose in [ , ], the number of reasoning steps necessary to reach the nash equilibrium, , is finite. not so when subjects have to choose in [ , ]. ho et al. ( ) call the two types of games finite-threshold and infinite-threshold, respectively. in our one-shot games we do not observe any difference in the results of the two types of games that can be reasonably attributed to this particular characteristic. ft-data ( subjects) , , , , , , , choices re la ti v e f re q u e n c ie s average . , winning number: ex p a n sion-data ( subjects) , , , , , , , c h o i c e s re la ti v e f re q u e n c ie s average . winning number: . spektrum-data ( subjects) , , , , , , , choices re la ti v e f re q u e n c ie s average , winning number: , figure to . frequencies of choices in the three newspapers’ experiments fact : once subjects reach the second, or third reasoning level, they jump all the (infinite) steps towards nash: one, two (three), infinity. analyzing the comments of those entrants in the s experiment who describe the equilibrium process of infinite iteration , we find that the average number chosen by them is , with % of them choosing below . we state this as: fact : a significant proportion of the subjects ( / = % in our sample) who reach all the way to nash, bounce back to choose a number larger than the equilibrium. however, most of them ( / = %), stay below and thus clearly below the numbers corresponding to levels of reasoning from to (numbers around , and ). many economists (see plott ( )) have argued that phenomena that appear irrational could be the result of rational players expecting others to behave irrationally. fact is an example that confirms this observation: many rational players do not choose the nash equilibrium because they take into account the bounded rationality of others. but there is another side to this fact: fact : a significant proportion of subjects ( / = % in our sample) who comment on reaching the equilibrium, choose a number from to . turning the previous statement upside down, we could say that a phenomenon that appears rational (choosing the nash equilibrium) may be the result of players expecting, irrationally, that other players will behave rationally. in other words, that what is taken for rational behavior represents, in fact, a boundedly rational ignorance of other players bounded rationality. in psychology this is known as “false consensus” (see dawes ( )), a situation that appears when people assume that other players reason as themselves. notice that numbers above are scarcer in ft than in the other two experiments. one reason for this fact, already suggested above, may be that in the ft description of the game an example that selected a low number was presented. since this may have pointed the way towards lower numbers in the ft experiment, we may be justified in comparing the experiments using we randomly selected comments out of all comments that identify the equilibrium, and classified their behavior. only numbers lower than . in figure we compare the s results and the ft results in a quantile-quantile plot, when all the results above have been removed form the two experiments. in the figure, it appears that the distributions of the numbers chosen in both experiments are almost identical, despite the non-normality of both distributions, the different subject pools, and the large number of subjects involved. indeed, there is no significant difference between the two distributions when applying a conventional test, like the mann-whitney-u-test, despite the high power of the test induced by the large number of observations. here we have, then, two experiments, run among two large populations presumed to be rather different (one made up mostly of uk businessmen and economists, the other made up of german scientists), whose results are undistinguishable. s f figure . quantile-quantile plot of choices to in ft and s we can summarize this observation as: fact : two large subject pools, drawn from different countries and from different professional backgrounds, answer the beauty-contest game in ways that are statistically indistinguishable. . comparisons with lab experiments one purpose, perhaps the main purpose, of running experiments out of the lab is to help critically assess the assumption of “parallelism”. do we see, then, similarities or differences between beauty-contest experiments run in labs and in newspapers? before entering into a detailed comparison, it is worth mentioning some of the basic differences between the two types of experiments due, most of them, to the increased loss of control occurred in experiments carried out in newspapers. this loss of control should reshape the design of experiments’ methodology when moving away from the full control provided by the lab. it involves: . sampling error experimentalists know that there is sampling error in their experimental results. they know that their subjects are not representative of the population at large, but are confident they have the ability to control the relevant characteristics of their samples. in a newspaper experiment, the experimenter looses some additional control of the sample. . information seeking subjects of newspaper experiments may go to great lengths to submit informed answers. one interesting variety of information-seeking behavior on the part of some subjects consists, of all things, in running a parallel experiment. some participants mentioned that they had run versions of the same experiment among friends, relatives or school classes, to help them decide what number to submit. in one case that we comment below in footnote , a potential subject of the s experiment started in the internet his own beauty-contest. another reader of s run the experiment in her math-class and then submitted the joint bid of her class mates (which was close to nash equilibrium,). of the subjects in the s game who reported that they had run their own experiment, % chose a number between and (the winning numbers in the three newspapers’ contests were in this interval), whereas in the total population only % chose a number in this interval. in addition, quite a few participants used an excel spreadsheet in order to calculate the best response to a distribution of numbers selected by them, typically with the pivotal numbers and having a high number of frequencies. whether this behavior may or may not have an undesirable effect on experiments run in newspapers is perhaps a moot issue, but it certainly helps to propagate out of academic circles the use of the experimental methodology as a road to enlightenment. . coalition forming if an experimenter wants to avoid the forming of coalitions in the lab there are usually ways of ensuring that this is the case. not so in a newspaper experiment. in fact, we know that in all three experiments there were attempts of coalition forming , although with little impact on the results (except for a larger than expected frequency of ). should newspapers experiment become more prevalent, and prizes larger, readers might find it worth organizing stable coalitions to participate in them, in the same way that it pays to organize rings of bidders in public auctions. . number of answers per subject the comment (see appendix) exemplifies a wide variety of comments we received: a) the idea of choosing a favorite number, b) reasoning according to the iteration model and c) the equilibrium concept. the attempt was blatant in e. allowing for the use of e-mail to submit numbers, we made it easy for a ring leader to spread the word among his e-friends to enter the number , so that he could increase his chance of winning by choosing a large number. in fact, we were recipients of one such e-mails and what we saw was interesting. the proposition was not a profit-sharing colluding agreement. instead, the ring leader asked friends to start a chain-letter of entrants playing , mentioning without further details that this way they were participating in an “economic experiment”. are we witnessing, thanks to internet, the spawning of a new form of collusion, with a leader controlling both information and profits, and some instrumental followers who participate without gain or cost? when large numbers of subjects are involved and the means of communicating between subjects and experimenters are diverse, it is quite difficult to enforce the rule of “one person one answer”. on the other hand, this rule becomes less important as more subjects are involved. in newspaper experiments it may not even make any precise sense to talk about number of answers per person. one person can send many answers under different names or have her entire family, or her friends, sending answers on her behalf. we know, for instance, that a schoolteacher invited over students to participate in the s experiment. the coalition forming problem and the problem of several answers on the part of a single individual may easily melt into each other. nevertheless, it is conceivable that, in some newspaper experiments, a very determinate person might affect significantly the results by entering a large number of decisions. of these potential differences between lab and newspaper experiments, the first two have revealed themselves as the most interesting. in the remaining of this section we present and compare the main features of different experiments collected from different sources (see table ). experiments to involve undergraduate students ( - in bonn, in caltech) with about minutes to think and no communication among them. experiments and are take-home experiment and experiments and are in-class sessions which all involve nd year undergraduate students from the intermediate micro classes in universitat pompeu fabra with very limited knowlegde in game theory. communication among the students was not constrained. experiment is a take-home exercise with game theory students of bettina rockenbach, university of bonn. experiments and involve economists (mainly game theorists and experimentalist). experiment was done by e-mail at universitat pompeu fabra among colleagues and graduate students from the department of economics and business. experiment is an e-mail game run by a participant of the s experiment , and experiments to are the ones done with readers of s, e and ft, respectively, and reported above. to help making his decision, as mentioned above, one participant in the s experiment decided to run on internet his own replication of the experiment. the answers that he received show the same common pattern of iterated reasoning. the winning number in his experiment was . . he submitted a slightly lower number ( . ) and was very close to win the s prize, the winner being the number . . a difference of . points in two experiments, one exp. numbers (month/ year) data collected by subject pool no. of players per session (total) payoffs time to submit the number submission by type comments - ( / , / ) nagel ( ), nagel (unpub.) undergraduates at bonn and (various faculties) at bonn and caltech - ( ) dm to winners, dm show up fee $ and $ show up fee min. immediately optional - ( / ) various instructors at upf (unpub.) nd year economic undergraduates at upf - ( ) pesetas ($ ), split if tie min. or week immediately or hand-in personally optional ( / ) rockenbach (unpub.) rd- rth year undergraduates in game theory class, bonn ( ) dm ( dm), split if tie weeks hand in personally optional - ( / , / , / ) nagel (unpub.) game theorists/ economists in or before seminars - ( ) min. or week immediately or by e-mail optional ( / ) matthias, a participant in s newsgroup in www dm or book week e-mail optional ( / ) thaler ( ) in financial times readers of f tickets london-ny or london-chicago weeks letters required to become a winner ( / ) bosch, nagel ( ) in expansión readers of e . pesetas ($ ) week letter, e-mail fax optional ( / ) selten, nagel ( ) in spektrum der wissenschaft readers of s dm ($ ) random draw if tie weeks letter, e-mail optional table . design and structure of experiments in order to assess the differences among these beauty-contest experiments in labs and newspapers and to compare their results, we have constructed in figure the box plots associated to the responses in each of the experiments. notice that box plots are drawn in such a way that % of the distribution is below the line dividing the box. with subjects, the other with , ! value figure . distribution of data in single experiments. the lower and upper side of the box indicates the nd and rd sÍmbolosÍmboloquartile of the distribution, q and q . therefore, the box spans the middle half of the data and the length of the box is the interquartile range (iqr). the “whiskers” at either end extend to the smallest and largest observations that are within [q - . iqr, q + . iqr]. points that are outside this interval are shown with circles. note the high variation across experiments of the median of the distribution (i.e., the level of the line dividing the box). among the experiments, the first four are clearly distinguished from the rest by the fact that the nash equilibrium of the game is never selected. this corresponds to four sessions run with undergraduates at the university of bonn (see nagel ( )). this is the most significant difference in the choices observed in lab-experiments and in newspaper experiments. in experiments and the median of the distribution is close to zero ( % of the subjects were at the nash equilibrium). other than subject pool, time availability seems to be a factor in the frequency differences observed in choosing the nash equilibrium. to test it, we run, at universitat pompeu fabra, a take-home experiment among undergraduate students with very limited knowledge of game theory, giving them one week to return their number choice (experiments and ). we observed in it a clear increase in equilibrium choices (about %), still below the newspapers average frequency of %. at the other extreme, when only game theorists are present in the experiment, the -choices are between % and % (experiments - , with and as “take-home” experiments). we can state these results as: fact : time availability seems to have some impact on the frequency of equilibrium responses. fact : subject-pool can have an important effect on the frequency of choices near the equilibrium. fact represents a warning. sampling error has to be carefully monitored in experiments. in spite of these differences in frequencies, all experiments show a common and important pattern. we refer to the iterated best reply reasoning introduced in nagel ( ). a thorough analysis of this pattern requires the use of statistical techniques. in the following section we comment on some of the statistical procedures used in previous work and describe the procedure that we use to analyze the data from the experiments under consideration. . statistical analysis of iterated reasoning the seminal paper by nagel ( ) uses the theoretical values of the iterated best replies starting from (in experiments labeled here to ) as the center of step-k reasoning intervals. in the beauty-contest game, this was the first attempt to characterize empirically the heterogeneous selection principles of agents assumed to iterate over best replies. from a statistical perspective, the fact that this method imposes the intervals’ centers instead of estimating their locations, supposes a drawback. stahl ( , ) describes the data of nagel ( ) with a boundedly rational rule learning model using the iterated model *( / )k. an individual with type-k initial propensity (so called disposition) is more likely to use rule k than any other rule. in order to avoid identification problems, the set of dispositions is assumed to be equal to the set of behavioral rules. players evaluate the ex-post performance of these rules using step-k reasoning. the econometric specification is completed by assuming that the choices in each step of reasoning belong to the family of truncated normal distributions in the [ , ] interval. for the type called “– ”, players that do not learn, stahl ( ) includes an additional uniform distribution. from the econometric perspective the specification becomes a mixture of distributions where the parameters to be estimated are the means, variances and proportions of each type. however, from the underlying theoretical model and the particular specification assumed, the moments of these distributions are constrained across them. the estimation procedure is maximun-likelihood. ho, weigelt and camerer ( ) use also beauty-contest results to investigate the proportion of players with different levels of reasoning. their procedure assumes that players, at each level of reasoning, believe they are at one level of reasoning deeper than the rest. ho et al. determine the mean and variance of each level-of-reasoning interval from the value of the mean and variance of level- players who choose from a truncated normal distribution. the idea being to assign the outcomes in each interval to the different levels-of-reasoning types. using maximum-likelihood, they estimate the mean and variance of level- players and the proportion of subjects in each interval. this approach, although interesting, suffers from several shortcomings. first, the results are very sensitive to the assumption about subjects’ perceptions of each other. even without changing the basic iterated dominance criterion, the analysis leads to very different results if players exhibit different levels of self-confidence. second, the authors impose a restrictive specification that ties the mean and the variance of each level-of-reasoning to the mean and the variance of level- distribution. stahl and haruvy ( ) use also maximum likelihood to uncover and test the selection principles used by different types of agents. the econometric specification is, as in the case of ho, weigel and camerer ( ) and stahl ( , ), a mixture distribution model. the experimental results are obtained from twenty symmetric x games. the selection principles tested include three deductive strategies (payoff dominance, security selection and risk dominance), three bounded rationality rules (level-n rules), one optimistic rule, one pessimistic rule and a hybrid rule. their methodology also allows testing the homogeneous population model versus the heterogeneous model. haruvy and stahl show that the predictive power of deductive equilibrium principles is very small and that even a level- rule of bounded rationality has a hit rate much higher than deductive rules in the homogenous case. for this reason their base model includes only one deductive rule (uniform nash equilibrium) instead of the original three. their results show that the most likely set-up includes heterogeneous agents with a high weight of level- bounded rationality rules. deductive selection principles do not add any predictive power. haruvy ( ) proposes a non-parametric technique to find modes, or local maxima, in a kernel estimated probability density function. he applies this method to two data sets. the first is a set of fifteen symmetric x games. the second one is essentially the same as in haruvy and stahl ( ), with the players being asked to specify the distribution of the other participants’ choices that led to their choices. therefore, the data were in the form of the probabilities of the strategies of other agents as described by each agent . the main idea of this non-parametric estimation is to change the bandwith parameter in order to modify the smoothing of the density surface and to find modes where probability mass is concentrated. the larger the bandwith the smoother is the surface and, therefore, less modes could be observed. our approach, as in ho et al ( ) and haruvy and stahl ( ), is based on a mixture distribution model, but without imposing any particular structure on the mean and variance of each distribution in the mixture. the set of experiments that we are analyzing provides multiple group data {xig, i = , …, ng}g= g, where xig corresponds to the choice of the ith subject in the gth group. as can be seen from table below, we have aggregated the experiments in different an important question with this kind of data is the possibility that individuals are not able to quantify their beliefs using probabilities. groups (g = ), from lab experiments to newspapers’ experiments. in the same table one can also find the values of the group sample sizes, ng. we assume that the data xig correspond to iid observations from a mixture of various normal distributions truncated at and and a uniform distribution in [ , ]. the normal components are assumed, with one exception spelled below, to have unconstrained means µk and variances σ k, k = , ,…, k- . here k denotes the number of normal components of the mixture. the normal distributions correspond to choices under levels of reasoning to maximum, while the uniform distribution collects the remaining choices, the level reasoning. we distinguish two types of parameters: ) those that characterize the mixing proportions, i.e. the weights of each level of reasoning in the population and ) the means and variances of the normal components of the mixture. the mixture model that we consider can be written as fx (x, θ) = π f (x, ζ ) + …+ πk fk(x, ζk) + πu fu, where fx (x, θ) denotes the density function of the mixture distribution at the value x. θ = (π´, ζ´)´, where π is a vector that collects the mixing proportions πk's, and ζ is a vector collecting the component parameters ζk = (µk, σk )´. the fk's correspond to normal distributions of mean µk and variance σ k, for k = ,…, k, and fu corresponds to a uniform distribution in [ , ]. as mentioned above, we keep the component parameters unconstrained , i.e., they are determined by the data themselves, with one exception. for the sake of the stability of the model when applied to small samples, we chose one of the normal distributions, the one that corresponds to the maximum reasoning level, fk, to have mean and variance . the mean of we also run an estimation assuming a mixture of log-normal distributions plus one uniform distribution. the fitted distributions were very symmetrical except for the distribution of choices at the maximum level of reasoning. the present specification with truncated normals reflects both the asymmetry at the maximum level and the symmetry of the remaining distributions, while keeping the description of the procedure simpler. identifiability of the mixture model requires the means of the components of the mixture to be sufficiently apart from each other, and within the permissible parameter space. that the estimation procedure converges is an indication that the condition is fulfilled. seemed a natural choice , while the variance of was selected for consistency with the observed variance when the model with unconstrained component parameters was fitted in the largest sample size experiment. we observed that the results of the statistical analysis were not sensitive to moderate changes in the value of this variance. the key aspect of the empirical investigation is whether the pattern of choices postulated by the iterated reasoning hypothesis shows up across the variety of groups (newspapers, students theorists). specifically, we want to see if choices cluster around the theoretical choices of . , . , . , …. another aspect of the statistical analysis is to evaluate the weight across groups of each level of reasoning. we consider two alternative model specifications, which differ according to the degree of invariance across groups of the model’s parameters. the unconstrained model, in which the different component parameters, means and variances, are unconstrained across groups, and the constrained model, in which the component parameters are constrained to be equal across groups. in both analyses, the mixing proportions are allowed to vary across groups. the technique we use is ml estimation of the mixture model using the expectation maximization (em) algorithm (e.g., dempster et al., ). the em algorithm is a procedure that iterates estimation between ζ and π, i.e., given ζ, π is computed, and the other way round, till convergence is achieved. estimation of the mixing proportions for each group is obtained from the mean, within groups, of the conditional probabilities of belonging to component k. note that the different analytic role of π and ζ in the likelihood function makes an em algorithm the natural approach to our problem. in fact, the em algorithm is found to be quite fast and stable in the problem at hand. once convergence is attained, standard errors of the parameter estimates are obtained using the approximation to the information matrix as proposed in louis ( ). recall that in the e data set, choices were in [ , ]. and in ft many participants thought the range to be from [ , ]. in the remaining data sets choices were from [ , ]. . results of the statistical analysis in table we show the results of the statistical method described above for k = . the first six rows describe the results of the unconstrained model, while the estimated parameters in the seventh row correspond to the constrained model. number of level- level- level- level-max level- observations ( . ) ( . ) ( . ) ( / ) . lab µ . . . . (experiments - ) σ . . . . proportion . . . . . . classroom µ . . . . (experiments , ) σ . . . . proportion . . . . . . take home µ . . . . (experiments , ) σ . . . . proportion . . . . . . theorists µ . . . . (experiments - ) σ . . . . proportion . . . . . . e-mail µ . . . . (experiment ) σ . . . . proportion . . . . . . newspapers µ . . . . (experiment - ) σ . . . . proportion . . . . . . constrained µ . . . . model σ . . . . proportion . . . . . table . results of the statistical analysis. sets of experiments with similar subject pools are aggregated in the groups described in the first column of the table. the second column shows the group sample sizes, ng. we report means µk and variances σk , and the proportion variable which indicates the proportion, in each group, of the population with different levels of reasoning. as an illustration, in figure , we represent the four different normal distributions - obtained in the unconstrained analysis of group (newspapers)- associated to the levels of reasoning , , and maximum. figure : the components of the mixture for the newspapers’group (exp. - ). in addition, in table , we present the log-likelihoods of the different estimations. it is interesting to note that the mean log-likelihood is similar for groups of experiments, an indication of similar goodness of fit among groups. number of mean observations - log l - log l . lab (experiment - ) . . . class (experiments , ) . . . take home (experiments , ) . . . theorists (experiments - ) . . . e-mail (experiment ) . . . newspapers (experiments - ) . . constrained model . . table . values of minus-log-likelihood of the estimated models the first result we want to highlight is that all groups have means close to the theoretical predictions. the constrained model shows means of . , . , and . , when the theoretical prediction puts them at . , . , and . . if we turn to the unconstrained model and look in particular at the group of experiments with the largest sample size (newspapers, row ), the means estimated in the decomposition of the data, . , . , and . , appear again quite close to the theoretical predictions. equally important, a comparison of the µ-values in the different groups shows little differences. on the basis of the statistical analysis above, we can state the following facts: fact : stability across very disparate experiments of the mean parameters of the component distributions. fact : estimated mean values are close to the theoretical values predicted by the game- theoretical model of iterated reasoning. one could be tempted to carry out a statistical test for the equality of the means of the composing distributions to the theoretical values predicted by the iterated reasoning hypothesis, i.e., values of . , . , . , etc. to carry out such test, however, we need to face the issue of high heterogeneity of the sample sizes across groups. such heterogeneity induces a high variation across groups of the power of a test for the same hypothesis. take for example group (newspapers’ experiments) with a sample size of , . if we test for the equality of the first- level mean to its theoretical value of . , we obtain a t-value of . that clearly rejects the null hypothesis (p-value is smaller than %). in contrast, if we take a group like classroom with sample size , the t-value turns out to be . , which clearly leads to acceptance of the null hypothesis (p-value greater than any reasonable significance value). therefore, in the large sample-size group we reject the hypothesis of the first-level mean being equal to the theoretical value, while we accept it in the small sample size group. but note that we reject the hypothesis of equality, the estimated mean differs from the theoretical prediction by . , while we accept the equality hypothesis when the difference is . . it is important to realize that the variation of the sample size that conditions the test, is an observation design artifact, nothing to do with the truth or falsity of the null hypothesis. clearly, as in many settings, an adequate interpretation of the test statistics requires to perform a power sensitivity analysis, in order to distinguish between statistical and substantive significance. this is an issue that we are currently investigating, but that, we feel, exceeds the scope of the present paper. with regard to the estimated proportions of the different reasoning levels, and especially the maximum-level reasoning, we observe that they vary considerably across experiments, a confirmation of fact above . this can be summarized as: fact : the proportions of subjects in each level of reasoning vary across experiments, i.e. it is highly determined by subject pools. in particular, the frequency of equilibrium choices in the newspapers experiments and in experiments with subjects trained in game theory is much higher than with un-trained undergraduates. this reflects the wide variation in the backgrounds of subject pools across experiments. the hypothesis that subjects have reasoning levels , , , or maximum seems to account, as has been shown, for the choice patterns of a wide variety of very heterogeneous experiments. one may wonder whether the statistical analysis of the data would give a better fit if we assumed that no subjects had level reasoning, i.e., if our mixtures model did not include a uniform distribution. to assess the need for the uniform distribution in the mixture, we have performed the analysis without such non-normal component. the results show a significant deterioration of the fit of the model, as measured by the schwarz information criterion. this extending the simple t-test to the multivariate setting of the equality of the three- (four-) level means to their corresponding theoretical values would yield, again, results dependent on the sample size. indeed, the corresponding wald test for the equality of the three means to their theoretical values yields for the newspapers and the classroom groups the values . and . respectively which, compared with a χ -distribution with degrees of freedom, induce a clear rejection of the null hypothesis in the case of the newspapers group and acceptance in the case of the classroom group (p-values are and . respectively). this is also true for the conditional proportions in the constrained model, that we did not print here. in fact, a formal test of the null hypothesis that the proportions are equal across groups, conditional that the component parameters (means and variances of each component) are equal, could be carried out. we take times the difference of log-likelihoods for the constrained model and the model that assumes identical components and proportions across groups (this analysis would correspond to pooling all the cases in a single group). the test statistic equals , which in relation to a χ -distribution with degrees of freedom (the difference on the number of parameters estimated) clearly rejects the null hypothesis that all the proportions are equal across groups. thus, the data clearly supports the fact . confirms that reasoning level- should be included as a uniform distribution in the mixture model. another issue of interest is the testing of the number of normal components of the mixture model. a test statistic that takes care of the non-standard issue that the null value of the parameter is at the boundary of the parameter space can be constructed using bootstrap methods. but the power of such a test would be probably low given the large difference in sample sizes among the groups of experiments. . conclusions experimental results are influenced by what marshak ( ) called the different costs of thinking, calculating, deciding and acting. grand-scale experiments of the sort that can be run through a newspaper can test whether the results of the lab experiments change under variations in sample sizes and rewards but also when these different costs are modified. a population more heterogeneous than undergraduate subjects -as one is likely to encounter in a newspaper experiment- will include subjects with wide different costs of thinking and calculating (due to different education, training or information), different cost of deciding (at leisure vs. the time- constraint imposed in the lab), and different costs of acting (ready access to e-mail and fax or not). a richer world with less control. that three experiments, run in different countries, for different newspapers, catering at different populations, yield results that are similar and, in two cases, indistinguishable from each other, is a clear indication that we are observing a pattern of behavior that must be quite common. that, in addition, the iterated reasoning observed with these large and diverse populations is also a pattern observed in lab experiments with subject pools of undergraduate, graduate students and economists, seem to clearly indicate that the “parallelism” assumption between lab and field has we repeated the previous estimation procedure for k = . the results indicate that the theoretical regularities are sustained (the mean of the fourth composing distribution is on average at . , when the theoretical prediction would put it at . ). but the convergence problems for one group (theorist) when we use the k= specification been vindicated for the iterated reasoning hypothesis in beauty-contest experiments. in fact, we are not aware that such a wide empirical corroboration of individual behavior has been previously observed, or even tried. in addition, the paper shows that some basic patterns of behavior, specifically the individual depth of reasoning, are subject specific. this observation should warn experimentalists to apply with caution the results of their experiments to the wider world. to sum up, the two main conclusions of the paper are: conclusion : across subject pools, different sample sizes, and different methods of selecting the data, iterated reasoning patterns are stable and remain similar to the theoretical values predicted by the bounded rational model of iterated reasoning. conclusion : the proportions of subjects employing different levels of reasoning are subject-pool specific. could also be taken as indication of overparameterization, at least in the case of small sample size groups. references bosch-domènech, antoni 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( ). “is step-j thinking an arbitrary modelling restriction or a fact of human nature?” journal of economic behavior and organization, ( ), - . stahl, dahl o. and ernan haruvy ( ). “empirical tests of equilibrium selection principles in symmetric normal-form games.” working paper university of texas. stahl, dahl o and paul w. wilson ( ).“experimental evidence on players' models of other players.” journal of economic behavior and organization, ( ), - . thaler, richard ( ).“giving markets a human dimension.” financial times, section mastering finance , june , . appendix comment by participants in the s-experiment (translation from german into english): i would like to submit the proposal of students of my math class grade e of the felix-klein-gymnasium goettingen for your game: . . how did this value come up? johanna …asked in the math-class whether we should not participate in this contest. the idea was accepted with great enthusiasm and lots of suggestions were made immediately. about half of the class wanted to submit their favorite numbers. to send one number for all, maybe one could take the average of all these numbers. a first concern came from ulfert, who stated that numbers greater than / had no chance to win. sonja suggested to take / of the average. at that point it got too complicated for some students and the decision was postponed. in the next class helena proposed to multiply / by / and again by / . however, ulfert disagreed, because starting like that one could multiply it again by / . others agreed with him that this process could be continued. they tried and realized that the numbers became smaller and smaller. a lot of students gave up at that point, thinking that this way a solution could not be found. others believed to have found the path of the solution: one just has to submit a very small number. however, they could not agree about how many of the people participating would become aware of this process. johanna supposed that the people who read this newspaper were quite sophisticated. at the end of the class, to students heatedly continued to discuss the problem. the next day i received the following message: […] we think it is best to submit the number . . اهی فلسفی ژپوهش بُار ي تابستان / / شمارٌ سال آل زیبایی و زیبایی وابسته در فلسفه کانت دهاینسبت یجًاد امیه خىدق ٔؿئَٛ( ٢ زا٘كز٢ٛ زوتط٢ حىٕت ٞٙط ز٣ٙ٤ زا٘كٍبٜ از٤بٖ ٚ ٔصاٞت)٤ٛ٘ؿٙسٜ علی سلماوی ٕٞساٖ اؾتبز٤بض ٌطٜٚ فّؿفٝ ٞٙط زا٘كٍبٜ ث٣ّٖٛ ؾ٥ٙب چکیدٌ وٙس. اٚ أط ظ٤جب ضا زض چٟبض زل٥مٝ ٔتٙبْط ثب احىبْ ُٔٙم٣ ثطضؾ٣ ٣ٔ ،«٘مس ل٠ٛ حىٓ»وب٘ت زض ْ «ٔٙتس٢ غب٤تت »زض زل٥م١ ؾْٛ ثط ٔجٙب٢ تح٥ُّ ٔفْٟٛ و٥ّس٢ ٔحتٛض اظ ظ٤جتب٣٤ ٤ٗٙت٣ ، ثتٝ تٗط٤فت٣ فتط ٝ »ضؾس. زض ش٤ُ ٥ٕٞٗ زل٥مٝ، زٚ ٔفْٟٛ ٔٙس٢ ش٣ٙٞ( ٣ٔ ٔٙس٢ ثسٖٚ غب٤ت )غب٤ت غب٤ت ٚ « ظ٤جب٣٤ ٚاثؿتت ٔٙس٢ ٥ٖٙت٣ ٞب ثط ٔجٙب٢ غب٤ت قٛز وٝ زاٚض٢ ظ٤جبقٙبذت٣ زض ٞط ز٢ٚ آٖ ٥٘ع ُٔطح ٣ٔ« ب٣٤آَ ظ٤ج ا٤سٜ» قتٛز. ٌطفتتٝ ٔت٣ فطو ثطا٢ زاٚض٢ پ٥ف آٖ ثب ٔٛافك ٥ٖٗ وٕبَ ٚ ٥ٖٗ چ٥ؿت٣ ثط زاَ اؾت ٚ ٔف٣ٟٔٛ ا٤تس٠ آَ ظ٤جب٣٤، ٔفْٟٛ حبنُ اظ رٕٕ ا٤س٠ ٖم٣ّ ٚ فطو زض ظ٤جب٣٤ ٚاثؿتٝ، وٕبَ ٥ٖٗ ٚ زض ا٤سٜ ا٤ٗ پ٥ف زضثتبض٠ ٔتٗبضف ظ٤جبقٙبذت٣ اؾت؛ أب ا٤ٗ ز٤سٌبٜ ٔتٗبضو ثب ا٤ٗ انُ ظ٤جبقٙبذت٣ وب٘ت اؾت وتٝ زاٚض٢ ٔٙتس٢ ٚ ٘تٛٔ اؾت. ا٤ٗ ٘ٛقتبض ثتب ثطضؾت٣ ٔفٟتْٛ غب٤تت ش٣ٙٞ ٔتى٣ ٔٙس٢ غب٤ت ٤ه نطفبً ثط أط ظ٤جب ضظـ ظ٤جبقتٙبذت٣ ا٤تٗ زٚ آَ ظ٤جب٣٤، زضنسز تج٥٥ٗ چٍت٣ٍ٘ٛ ا ٔٙس٢ ٣ٙ٥ٖ زض ظ٤جب٣٤ ٚاثؿتٝ ٚ ا٤سٜ غب٤ت ثبقس تب رب٤ٍبٜ ا٤تٗ زٚ ٔفٟتْٛ زض ٞب ثب ٤ىس٤ٍط ٣ٔ ٔفْٟٛ ٚ زض ٟ٘ب٤ت ثطضؾ٣ ٘مبٌ اذتالف ٚ اقتطان آٖ فّؿف١ وب٘ت ٔكرم قٛز. ٔٙتس٢ ٔٙتس٢ شٞٙت٣، غب٤تت آَ ظ٤جب٣٤، ظ٤جب٣٤ ٚاثؿتٝ، زاٚض٢ ظ٤جبقٙبذت٣، غب٤ت ا٤سٜ َای کلیدی: ياژٌ .٣ٙ٥ٖ / / تأ٥٤س ٟ٘ب٣٤: / / تبض٤د ٚنَٛ: - - e-mail: a.khandaqi@gmail.com ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ مقدمٍ ٖ ضا زض ش٤ُ زلب٤ك چٟبضٌب١٘ حىٓ شٚل٣ تزع٤ٝ ٚ تح٥ُّ ٣ٔوب٘ت أط ظ٤جب وتٝ وٙس. ثتب آ أب ا٤ٗ زلب٤ك چٟبضٌب٘ٝ ٔتًب٤ف ثب چٟتبض نتٛضم ُٔٙمت٣ حىٓ شٚل٣ ذٛز حىٓ ُٔٙم٣ ٥٘ؿت، قٛز. وب٘ت زض ٞط زل٥متٝ ثركت٣ اظ تٗط٤تف احىبْ ٣ٙٗ٤ و٥ف٥ت، و٥ٕت، ٘ؿجت ٚ رٟت ُٔطح ٣ٔ ٔٙتس٢ س٤ٍط٘تس. زل٥مت١ ؾتْٛ ثتب قتطح ٔفٟتْٛ غب٤تت زٞتس وتٝ ٔىٕتُ ٤ى ضا اضائتٝ ٔت٣ « ظ٤جب» (purposiveness) ،ٔٙس٢ ٤ه ٥ٖٗ، تب رب٣٤ وٝ ا٤ٗ نتٛضم ظ٤جب٣٤ ضا نٛضم غب٤تأط ظ٤جب ٘ىتت١ حتبئع (. ، ، ة وب٘تت، )وٙس ثسٖٚ تهٛض غب٤ت٣ زض ٥ٖٗ زض٤بفت قٛز، تٗط٤ف ٣ٔ اٚض٢ ظ٤جبقٙبذت٣ اؾت. اظ ٔٙٓتط ٢ٚ، ٔٙس٢ زض ز ا٥ٕٞت زض ا٤ٗ زل٥مٝ، تٗط٤ف وب٘ت اظ ا٘ٛأ غب٤ت ( subjective purposiveness)(ش٣ٙٞ) نٛض٢ نطفبً ٔٙس٢ غب٤ت ٤ه ثط ظ٤جب زضثبض٠ زاٚض٢ ٣ٙ٥ٖ ٔٙس٢ غب٤ت ٌٛ٘ٝ ٞط اظ أط ظ٤جب ،اؾبؼ ٥ٕٞٗ ثط اؾت. ٔتى٣ غب٤ت، ثسٖٚ ٔٙس٢ غب٤ت ٣ٙٗ٤ ٤ٗٙت٣ ،٣ٙ٥ٖ زضٚ٘ت٣ ٔٙس٢ غب٤ت ٚ ؛ؾٛزٔٙس٢ ٣ٙٗ٤ ،(objective purposiveness)ث٥ط٣٘ٚ نتٛضم ٔٙس٢، غب٤ت انُ ٔجٙب٢ تأ٣ّٔ ثط حىٓ ل٠ٛ (. ، ة ٕٞبٖ،) اؾت ذب٣ِ ٥ٖٗ، وٕبَِ ٝ ٞتب، نٛضم ا٤ٗ ا٘تعأ ثب ٚ زازٜ لطاض تأُٔ ٔٛضز ش٣ٙٞ ثٝ ٘حٛ ضا ا٥ٖبٖ ٔحى ِتصت٣ احؿتبؼ ثت ٝ ٕٞتبٖ، )٘ب٥ٔتس ظ٤جبقٙبذت٣ ِصم احؿبؼ ضا آٖ تٛاٖ ٣ٔ وٝ ٤بثس ٣ٔ زؾت . (vii، - ز٤جبچت ( ضا اظ ظ٤جتب٣٤ free beautyاٚ زض اثتسا٢ ثرف قب٘عزٞٓ زض ٥ٕٞٗ زل٥مٝ، ظ٤جب٣٤ آظاز)ٕٞچ٥ٙٗ ٔف٣ٟٔٛ زاَ ثتط ،ظ٤جب٣٤ آظاززض ا٤ٗ تفى٥ه، .وٙس تفى٥ه ٣ٔ (dependent beautyٚاثؿتٝ) ٥ٌطز، أب ظ٤جب٣٤ ٚاثؿتٝ چ٥ٙٗ ٔف٣ٟٔٛ ٚ وٕبَ ٥ٖٗ ٔٛافك ثتب آٖ فطو ٣ٕ٘ چ٥ؿت٣ ٥ٖٗ ضا پ٥ف قتٛز ٚ زٚٔت٣ وتٝ ظ٤جب٣٤ لبئٓ ثٝ شامِ ا٤ٗ ٤ب آٖ ق٣ء ذٛا٘تسٜ ٔت٣ ،٥ٌطز. ا٣ِّٚ فطو ٣ٔ ضا پ٥ف ه ٔفٟتْٛ اؾتت وتٝ تحتت ٤ت ٚاثؿتٝ ٚاثؿتٝ ثٝ ٔفْٟٛ اؾت )ظ٤جب٣٤ ٔكطٌٚ(، ثٝ ظ٤جب٣٤ ا٥ٖب٣٘ ٞب، ثؿ٥بض٢ اظ پط٘سٌبٖ، ثؿ٥بض٢ اظ أٛض٢ ٕٞچٖٛ ٌُثط ا٤ٗ اؾبؼ، ٥ٌط٘س. )غب٤ت ذبل( لطاض ٣ٔ بغصٞب٢ ز٤ٛاض٢، ٔٛؾت٥م٣ ٞب، و ٞب٢ تع٣ٙ٥٤ حبق٥ٝ ٞب٢ زض٤ب٣٤، ٘مٛـ ٤ٛ٘ب٣٘، قبخ ٚ ثطي نسف ٞتب، ب٣٤ آٖظ٤طا زض قبِٛز٠ حىتٓ ثتٝ ظ٤جت .٥ٌط٘س ٣ٔ زض ظٔط٠ ٔهبز٤ك ظ٤جب٣٤ آظاز لطاضثسٖٚ والْ، ٔٙس٢ ٣ٙ٥ٖ زض٣٘ٚ( وٝ تز٥ٕٕ وخطام ثٝ آٖ ٘ؿجت زازٜ قٛز، ٚرٛز ٘تساضز. ٥ٞچ ٘ٛٔ وٕب٣ِ )غب٤ت ثٝ قٕبض ٞب٢ ظ٤جب٣٤ ٚاثؿتٝ زض ٔمبثُ أٛض٢ چٖٛ ظ٤جب٣٤ ا٘ؿبٖ، اؾت ٚ ٖٕبضم ضا ثٝ ٖٙٛاٖ ٕ٘ٛ٘ٝ ثب٤س ثبقتس ٤تب ثتٝ وٙس ق٣ء چٝ ٞب، ٔفْٟٛ غب٤ت٣ وٝ ٥ٗٔٗ ٣ٔ . ظ٤طا زض حىٓ ثٝ ظ٤جب٣٤ آٖضٚ٘س ٣ٔ .( - ، ةقٛز)ٕٞبٖ، فطو ٌطفتٝ ٣ٔ ٔف٣ٟٔٛ اظ وٕبَ آٖ، پ٥ف ،ٖجبضم ز٤ٍط أب زض ا٤ٗ ٥ٔبٖ .زا٘س ٌكب٢ ثؿ٥بض٢ اظ ٔٙبلكبم ظ٤جبقٙبذت٣ ٣ٔ ا٤ٗ تفى٥ه ضا ضاٜوب٘ت / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ اـ ٚاضز وٙتس. ؾبظز تب ٔف٣ٟٔٛ ز٤ٍتط زض ٘ٓتبْ ظ٤جبقٙبؾت٣ ٔهٕٓ ٣ٔضا اؾبؾ٣ وب٘ت ١ِ ٔؿأ٤ه ٥ٞچ ٘ٛٔ لبٖ٘ٛ ٣ٙ٥ٖ اضائٝ زٞس. ظ٤طا اضائ١ ٞط ٘ٛٔ لبٖ٘ٛ ٣ٙ٥ٖ ٔؿتّعْ ،تٛا٘س ثطا٢ شٚق وب٘ت ٣ٕ٘ ثٝ وبض٥ٌط٢ ٔفب٥ٞٓ اؾت ٚ ثٝ وبض٥ٌط٢ ٔفب٥ٞٓ، حىٓ ظ٤جبقٙبذت٣ ضا تجتس٤ُ ثتٝ حىتٓ قتٙبذت٣ وٙس. اظ ٥ٕٞٗ ضٚ، ثب تى٥ٝ ثط ٚرٛز ٔجتب٣٘ ا٘ؿتب٣٘ ٔكتتطن ٚ تٛافتك ُٔتطح قتسٜ زض احىتبْ ٣ٔ بقٙبذت٣ ثٝ رب٢ ٔٗطف٣ لبٖ٘ٛ ٤ب لٛا٥٘ٗ شٚلت٣ ٚ ظ٤جبقتٙبذت٣، ؾطٔكتك لتطاض زازٖ ثطذت٣ اظ ظ٤ج وٙس ٚ ا٤ٗ ٔخُ اٖال٢ شٚق ضا وٝ آقىبضا ثط ا٤س٠ ٘تبٔت٥ٗٗ ٖمتُ اظ ٔحهٛالم شٚق ضا پ٥كٟٙبز ٣ٔ ٘بٔتس ( ٔت٣ the ideal of beauty«)آَ ظ٤جتب٣٤ ا٤تسٜ »٤ه حساوخط )ٔبوع٤ٕٓ( ٔتى٣ اؾتت، ٥ٖٙت٣ ٔٙس٢ غب٤ت ٤ه اظ ٖم٣ّ ٔف٣ٟٔٛ ظ٤جب٣٤ آَ رب٣٤ وٝ ا٤سٜ (. اظ آ ٖ- ، ، ة)ٕٞبٖ ٞتب ُٔتطح ٔٙس٢ ٣ٙ٥ٖ اؾت، ا٤تٗ پطؾتف اؾت ٚ زاٚض٢ ظ٤جب٣٤ ٚاثؿتٝ ٞٓ حبو٣ اظ ٣ٖٛ٘ غب٤ت تتٛاٖ ٔٙس٢ شٞٙت٣ ؾتطٚوبض زاض٘تس، چٍٛ٘تٝ ٔت٣ قٛز وٝ اٌط احىبْ ظ٤جبقٙبذت٣ نطفبً ثب غب٤ت ٣ٔ ٖ ٚاثؿتٝ ضا زض ٘ؿجت ثب غب٤تآَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ا٤سٜ ٞتب ضا ٔٙس٢ ٣ٙ٥ٖ تٗط٤ف وتطز ٚ ٕٞچٙتبٖ آ آَ ظ٤جب٣٤ چٝ ٘ؿجت٣ ثب ظ٤جب٣٤ ٚاثؿتٝ زاضز؟ ا٤ٗ ٘ٛقتتبض ثتط زاضا٢ اضظـ ظ٤جبقٙبذت٣ زا٘ؿت؟ ا٤سٜ اضتجبٌ ا٤ٗ زٚ ٔفْٟٛ ثب ٤ىس٤ٍط ٚ آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ، ٔٙس٢ ا٤سٜ آٖ اؾت تب ثب تج٥٥ٗ غب٤ت ٞب ضا ثطضؾ٣ ٕ٘ب٤س. بقٙبذت٣ آٖاضظـ ظ٤ج مىدی عیىی مىدی ذَىی ي غایت غایت ٔٙس٢ ٚ ا٘ٛأ آٖ ضا زض ٞب٢ ُٔطح قسٜ، اثتسا ثب٤س ٔفْٟٛ غب٤ت رٟت پطزاذتٗ ثٝ پطؾف ل٠ٛ ذ٥بَ زض تأٔالم ٚ احىتبْ ظ٤جبقتٙبذت٣ ذتٛز، ،٘ٓبْ فّؿف٣ وب٘ت ثطضؾ٣ وطز. اظ ٔٙٓط وب٘ت وٙتس. وب٘تت ثتب تمؿت٥ٓ نتٛضم ٔحتى ا٥ٖتبٖ ضا تأٔتُ ٔت٣ ،ٔٙس٢ ش٣ٙٞ نطفبً ثط ٔجٙب٢ غب٤ت تط وٙس تب ٔف٣ٟٔٛ ضٚقٗ ٔٙس٢ ٣ٙ٥ٖ ثٝ ث٥ط٣٘ٚ )ؾٛزٔٙس٢( ٚ زض٣٘ٚ )وٕبَ ٥ٖٗ(، تالـ ٣ٔ غب٤ت ٔٙس٢ ٣ٙ٥ٖ ث٥ط٣٘ٚ ثٝ ٘ؿجت ذبضر٣ ٥ٖٗ ثب ز٤ٍط ا٥ٖبٖ ٚ ثب ٔٙس٢ ش٣ٙٞ اضائٝ زٞس. غب٤ت اظ غب٤ت ٣٘ٚ ارعاء وخ٥ط ثب ٔف٣ٟٔٛ اظ چ٥ؿت٣ ٥ٖٗ تٛرٝ زاضز. ٔٙس٢ ٣ٙ٥ٖ زض٣٘ٚ ثٝ ٘ؿجت زض وُ، ٚ غب٤ت ٣ٙٗ٤ تٛافك و٥ف٣ ارعاء ٖت٥ٗ ثتب ٔفٟتْٛ « وٕبَ و٥ف٣»ٔٙس٢ ٣ٙ٥ٖ زض٣٘ٚ ٥٘ع ثٝ وٕبَ زض غب٤ت ٌتطزز ٣ٙٗ٤ تٛافك و٣ٕ وخطام ثب ٔفْٟٛ چ٥ؿتت٣ ٖت٥ٗ تمؿت٥ٓ ٔت٣ « وٕبَ و٣ٕ»چ٥ؿت٣ آٖ ٚ ٓ » اظ اٚ بم ذب٣ِ اؾت. ٔمهٛزحىٓ شٚل٣ ٔحى اظ تٕب٣ٔ ا٤ٗ غب٤ ٚ ( ، ة ٕٞبٖ،) «حىت چ٥تع٢، زضثبض٠ ٘ٓط ٤ب ازٖب ث٥بٖ ثٝ ٔٙزط ٟ٘ب٤ت زض وٝ اؾت ا٢ تزطثٝ زض احىبْ ظ٤جبقٙبذت٣، نطفبً (.crawford, , )قٛز ٣ٔ ،اؾت چ٥ٙٗ چ٥ع٢ وٝ ا٤ٗ ثٝ آٌب٣ٞ آٖ، اظ تط و٣ّ حت٣ ٤ب ٘ٓتط ثبض٠ ظ٤جب٣٤ ق٣ء اْٟبضفطز زضبقٙبذت٣ فطز اؾت وٝ زض آٖ زض ٚالٕ، حىٓ ٣ٖٛ٘ اظ تزطث١ ظ٤ج ا٢ ثطؾس ٚ چٝ ٘ٛٔ وٝ فطز زض ٔٛارٟٝ ثب ق٣ء ٤ب احط ٞٙط٢ ثٝ چٝ ٘ٛٔ تزطثٝ وٙس. ثط اؾبؼ ا٤ٗ ٣ٔ ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ قٛز. ا٢ وؿت وٙس، ازٖب ٤ب ٘ٓط اٚ )حىٓ( ٔتفبٚم ٣ٔ آٌب٣ٞ تزطث٣ ٞب٢ حؽ ،ٖبَفٝ ٚ ٥ٞزبٖ اظ ٘بق٣ ِصم ثط ٔتى٣تٛا٘س ٣ٕ٘ شٚل٣ ٔحى حىٓ ٗ زَ انٛام ٤ب ظ٤جب ٞب٢ ضً٘ لج٥ُ اظ ٝ ثبقتس، ذتبل ٔفٟت٣ٔٛ ثتب ٚ ٘كت٥ ثتط ٔتىت٣ نتطفبً ثّىت ٚ ا٥ٖبٖ ذبضر٣ ثٝ ٚرٛز ٞب نٛضم ا٘تعأ زض تأ٣ّٔ حىٓ ل٠ٛ اٌط .)ش٣ٙٞ( اؾت نٛض٢ ٞب٢ ٤ٚػ٣ٌ ( شٞٙت٣ ٔٙس٢ غب٤ت) غب٤ت ثسٖٚ ٔٙس٢ غب٤ت ٔجٙب٢ ثط تٟٙب ٚ ٘ىٙس تٛرٝ وبضثطزٞب٢ ٔٛضز ٘ٓط آٖ ثٝ ا٥ٖبٖ، غب٣٤ ٚ ٔحى ٞب٢ نٛضم ا٘تعأ ٘ت٥ز١ ٚضظز، زض فٗب٥ِت ل٠ٛ فٟٓثب آظاز ٕٞب٣ٍٙٞ زض ٚ ٝ ٤بثتس ٔت٣ زؾت ضيب٤ت٣ ٚ ِصم احؿبؼ ٖ ٔت٣ وت ٘ب٥ٔتس ظ٤جبقتٙبذت٣ ِتصم احؿتبؼ ضا آٖ تتٛا (allison, , ). : قتٛز ٣ٔ ذٛز ٔتٛؾُ ذبل انَٛ ثٝ شٚل٣ اظ چٙس رٟت تأ٣ّٔ حىٓزض ز٤سٌبٜ وب٘ت، ٖ احؿبؼ ل٠ٛ ثٝ ؛(نٛض٢ ّٖت) حىٓ ا٤ٗ ث٥ٙبٖ ثٝ ٖٙٛاٖ لٛا آظاز ٕٞب٣ٍٙٞ ثٝ ٔحتتٛا ثتٝ ٖٙتٛا وٙس؛ ٣ٔ ت٥٥ٗٗ ثطتط حبِت ٤ه ثٝ ٖٙٛاٖ ضا ذبل ِصم ٤ه آٖ ثب ضاثُٝ زض حىٓ وٝ ،ٔبز٢( )ّٖت ٝ ذتبل تٕب٤ُ ثٝ ثبالذطٜ ٚ ؛غب٣٤( )ّٖتغب٤ت ثسٖٚ ٔٙس٢ غب٤ت نٛضم ثٝ )ّٖتت ظ٤جتب أتط ثت (.deleuze, , )آ٤س ٣ٔ ثٝ ٚرٛز آٖ اظ ظ٤جب أط احؿبؼ وٝ تبٔٝ(، ٖ ٚحتسم ٚ زازٖ ٘ٓٓ وب٘ت، اؾبؾ٣ ٞب٢ فطو اظ ٤ى٣ ثٝ ٔٛرت ٝ ثركت٥س وختطام ثت (critique of pure reason)«ٔحى ٖمُ ٘مس» ا٤ٗ فطآ٤ٙس زض. اؾت فٟٓ ل٠ٛ وبض ٔسضن، سٜ،تزازٜ قت طامتطح اؾتت. ازضان وخت تؾتٝ ٌتبْ ُٔت ٙس ٔتصوٛض تاؾتت. زض فطآ٤ت قتسٜ ط٤حتتك طام تز٥ٕتٕ تثتٝ وخت ٛالمتٔم اظ ٤ى٣ ؾطا٘زبْ اَالق ٚ ٥بَتذ ل٠ٛ ثٝ ٚؾ١ّ٥ وخطام آٚض٢ٕ ترٕ ُ ٤ته ٚحتسم ٤بثٙتس. زالِت٣ تزطث٣ ٚ ٣ٙ٥ٖ ٣ٔ ،ٔمٛالم ،َط٤ك ا٤ٗ ثٝ قسٜ وٝ ٖ وت ٝ ٔمتطٚ ثت ٕ ذ٥بَ زض چٝ ٞط. ٥٘ؿت ؾْٛ ٌبْ ٥٘بظٔٙس اؾت، زاٚض٢ ٔٛضز ظ٤جبقٙبذت٣ ِحبِ ثٝ وٝ غبئ٥ت رٕت ٓ » ثط وٝ ٞؿت، ٚحست٣ ٥٘ع ٚحسم ٚارس قٛز، ٗ ٔفتب٥ٞ (indeterminate concepts)«٘تبٔت٥ٗ طام( ٚ لت٠ٛ فٟتٓ )اِجتتٝ ٘تٝ ثتٝ ؾتٕت ت٥ٕٕ وختت ل٠ٛ ذ٥بَ )تزتحبنُ فٗب٥ِ ٚ وٙس ٣تٔ زالِت تحتت زازٖ لتطاض اظ اؾتت جبضمتٖت ،ٓتحىت ٠ٛتٕ وبض لتزض ٚال .٥ٗٗ( اؾتت٣ٟٔٛ ذبل ٚ ٔتتٔف ٥ٌتطز ٕ٘ت٣ ٤ب ٥ٌطز ٣ٔ لطاض قسٜ زازٜ س٠تلبٖ ٤ه تحت چ٥ع٢ آ٤ب وٝ ا٤ٗ زازٖ ٥عتت٥ٕ ٣ٙٗ٤ لٛاٖس، (kant, , b - and b - , a / b ). ا٤ٗ زض ثٙتتبثط ٔٙس٢ ش٣ٙٞ، ل٠ٛ حىٓ تأ٣ّٔ ثب٤س ارعا٢ وخ٥ط ضا زض رٟتت ٤تبفتٗ نتٛضم غتب٣٤ آٖ ٔتٛضز غب٤ت تٛرٝ لطاض زٞس ٚ ا٤ٗ وخطام ضا تحت ٚحست٣ ش٣ٙٞ، وٝ اظ اثتسا چ٥ؿتت٣ آٖ ّٔٗتْٛ ٥٘ؿتت، لتطاض / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ تهٛض اظ َط٤ك ازضان نطف نٛضم ٤ه ٔتّٗك قٟٛز ت زض حبِت٣ وٝ اظ ٤ته ؾتٛ، ثتب ٤ته زٞس. ٗ ٕٞطاٜ ٘جبقس ٚ اظ ؾ٢ٛ ز٤ٍط، ِصم ثٝ ٕٞطاٜ زاقتٝ ثبقس ت تٟٙب ثب شٞٗ ٘ؿجت زاضز ٚ ٔفْٟٛ ٥ٗٔ وٝ وب٘ت ٞط ٌٛ٘تٝ تٛاٖ ٌفت ضٚ ٣ٔ اظ ا٤ٗتٛا٘س حبو٣ اظ چ٥ع ز٤ٍط٢ ثبقس. ِصم حبنُ اظ آٖ ٣ٕ٘ وٙتس وتٝ ازٖب ٔت٣ ثط ٥ٕٞٗ ٔجٙب ؾبظز ٚ ٚ ٞب٢ ظ٤جبقٙبذت٣ ذبضد ٣ٔ ٔٙس٢ ٣ٙ٥ٖ ضا اظ زاٚض٢ غب٤ت ظ٤جبقٙبذت٣، حى٣ٕ ٔحى ٚ ثسٖٚ ٖاللٝ ٚ ثسٖٚ تٛرٝ ثٝ ٔفْٟٛ ٣ٙ٥ٖ ق٣ء ٚ ٤تب ٔفٟتْٛ حىٓ ٝ .ٔٙس٢ ٥ٖٙت٣ اؾتت اذالل٣ ٚ ثٝ َٛض و٣ّ غب٤ت ا٢ حىتٓ شٚلت٣ ضا ترط٤تت ٚ ظ٤تطا ٞتط ٖاللت (. ، ةٚ vii، ز٤جبچٝ : ، وب٘تثطز) اـ ضا اظ ث٥ٗ ٣ٔ َطف٣ ث٣ زیبایی يابستٍ فتطو زاَ ثط چ٥ؿت٣ ٥ٖٗ ٚ وٕبَ ٥ٖٗ ٔٛافك ثتب آٖ ضا پت٥ف ظ٤جب٣٤ ٚاثؿتٝ ٔف٣ٟٔٛ ٝ تت ٤ته تهت٤ٛط ٚلتت٣ ثتطا٢ ٕ٘ٛ٘تٝ، . اؾتت قت٣ء اظ لجّت٣ ؾبظ٢ ٔفْٟٛ ٥٘بظٔٙسٚ ٥ٌطز ٣ٔ وت زازٜ لتطاض ٔفب٥ٞٓ اٌط آٖ ضا تحت و٥ٙٓ، ٣ٔ ٔكبٞسٜ ضا ؾبذتٕبٖ ٤ه ٤ب ت اؾت چ٥ع٢ زٞٙس٠ ٘كبٖ ٝ ظ٤جتب٣٤ احؿبؼ ٥ٞچ تٛا٥٘ٓ ٣ٕ٘ت ِحبِ قٛز آٖ وبضوطز ثٝ ضرٛٔ ثب ٣ٙٗ٤ت ثبق٥ٓ ثبقت٥ٓ. زاقتت ٝ ضا ظ٤جب٣٤ ا٤ٗ ٥ٖٗ،وٕبَ ٔفْٟٛ ثب ٚاثؿتٝ ظ٤جب٣٤ ٕٞطا٣ٞ ز٥ُِ ثٝ ٔفؿطاٖ، اظ ثطذ٣ ُ ثت ٚ ٖمت َ آٖ، انبِت ا٘ىبض ثب اؾبؼ، ٥ٕٞٗ ثط ٚ زازٜ ٘ؿجت اذالق ٗ حهتٛ َ ٘ت٥زت١ ضا ظ٤جتب٣٤ ا٤ت اٖٕتب ٝ ظ٤جب٣٤ ٚ زا٘ؿتٝ آظاز ظ٤جب٣٤ ثٝ ٔٙحهط ضا ظ٤جب٣٤ اؾبؾبً ،ا٘س؛ اظ ٥ٕٞٗ ضٚ زا٘ؿتٝ ٖمُ زذبِت ضا ٚاثؿتت ٖ وٝ ا٢ ا٘س. ثٝ ثبٚض ا٤ٗ ٔفؿطاٖ، ق٣ اٍ٘بقتٝ ظ٤جبقٙبذت٣ اضظـ فبلس ٖمُ، زذبِت ثٝ ز٥ُِ ثتٝ ٖٙتٛا اظ ذبنت٣ ٘ٛٔ ٥ٗٔبضٞب، ا٤ٗ وٝ اؾت ٥ٖٗ وٕبَ اظ ٥ٗٔبضٞب٣٤ ٚارس اؾت، قسٜ زاٚض٢ ٚاثؿتٝ ظ٤جب٣٤ ٝ زاض٘س. پؽ ا٥ٖب٣٘ ٣ٔ ٖطيٝ اؾت، آظاز ظ٤جب٣٤ ثب ٔتفبٚم وٝ ضا ظ٤جب٣٤ ٝ ظ٤جتب٣٤ ٚارتس وت ا٘تس، ٚاثؿتت (.scarre, , and zimmerman, , آظاز٘تس) ٞتب٢ ٔتفبٚم اظ ظ٤جب٣٤ تتٛاٖ ازٖتب أب ا٤ٗ تفؿ٥ط ثٝ زال٣ّ٤ وٝ زض ازأٝ ث٥بٖ ذٛاٞس قس، ٘بزضؾت اؾت ٚ اظ ٥ٕٞٗ ضٚ ٣ٔ وطز وٝ ظ٤جب٣٤ ٚاثؿتٝ ٞٓ ٚارس اضظـ ظ٤جبقٙبذت٣ اؾت. )٘ؿجت ث٥ط٣٘ٚ ٣ٙ٥ٖ غب٤بم ثٝ ٚاثؿتٝ ظ٤جب٣٤ زض تٛاٖ ٌفت وٝ وب٘ت زض ٌبْ ٘رؿت ٣ٔ ثتٝ ٖٙتٛاٖ تت ٤ه و٥ّؿب ظ٤جب٣٤ ٕ٘ٛ٘ٝ، ثطا٢. ٘ساضز ذبضر٣ ٥ٖٗ ثب ز٤ٍط ا٥ٖبٖ ٤ب ؾٛزٔٙس٢( ٘ٓط ٝ ت ٍ وب٘ت ثطا٢ ظ٤جتب٣٤ ٚاثؿتتٝ ٞب٢ اضائٝ قسٜ تٛؾ ٤ى٣ اظ ٕ٘ٛ٘ٝ ٚ ؾتٛزٔٙس٢ ثتب ٘ؿتجت زض ٘ت ،(ث٥طٚ٘ت٣ ٥ٖٙت٣ ٔٙتس٢ غب٤ت)آٖ اذالل٣ ٚ ز٣ٙ٤ وطز ُٖٕ ٚ آ٣ٙ٥٤ ٔطاؾٓ ثطٌعاض٢ زض آٖ وبضوطز زض ا٤تٗ زاٚض٢، .٥ٌتطز ٔت٣ لطاض زاٚض٢ ٔٛضز( و٥ّؿب چ٥ؿت٣) آٖ وُ ثب ارعاء ٘ؿجت ثٝ ِحبِ ثّىٝ قتٛز. ثتط فطو ٌطفتتٝ ٔت٣ وٙس ق٣ء چٝ ثب٤س ثبقس )وٕبَ ق٣ء( پ٥ف ٔفْٟٛ غب٤ت٣ وٝ ٥ٗٔٗ ٣ٔ ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ ٥ٕٞٗ اؾبؼ، ا٤ٗ ظ٤جب٣٤، فمٍ ظ٤جب٣٤ ٚاثؿتٝ اؾت وٝ ٘ؿجت ثٝ ظ٤جب٣٤ آظاز ثتٝ ٚاؾت١ُ زض ٘ٓتط تٛاٖ آٖ ضا ٕٞچتٖٛ ٚ ٣ٕ٘( ، ة، وب٘ت، )زاضا٢ ذّٛل وٕتط٢ اؾت ،زاقتٗ وٕبَ ثٝ ٔطثٌٛ (، اظ زا٤ط٠ شٚق ذبضد وطز. ظ٤طا احىبcoleman, , ْ٘ٓط ثطذ٣ ٔفؿطاٖ) َ ثب ٘ؿجت زض وٝ آٖ ثب ٚ ٥٘ؿتٙس ٖمُ ٤ب فٟٓ اظ نبزضٜ احىب٣ٔ ٚاثؿتٝ، ظ٤جب٣٤ زاٚض٢ ٖت٥ٗ، وٕتب ْ . قتٛ٘س ٔت٣ زاٚض٢ ظ٤جتب أتط ثٝ ٔخبث١ ٕٞچٙبٖ أب ٥٘ؿتٙس، آظاز ظ٤جب٣٤ ٚ قٛ٘س ٣ٔ ْ اً٘تٕب ٔفٟتٛ آٖ ظ٤جبقٙبذت٣ اضظـ ٣ِٚ ثطز، ٣ٔ ث٥ٗ اظ ضا ظ٤جبقٙبذت٣ حىٓ ذّٛل چٙس ٞط ظ٤جب، ٥ٖٗ ثٝ ،وٕبَ ا٤تٗ أتط .زاضز ٚرٛز ٚاثؿتٝ ظ٤جب٣٤ زض آظاز ظ٤جب٣٤ اظ ٢ًٖٛ ٚ ٖٙهط ٕٞٛاضٜ ظ٤طا .وٙس ٣ٔ حفّ ضا قتٛز. اظ ٔٙٓتط اٚ، لت٠ٛ تط ٣ٔ وب٘ت ضٚقٗ لٛا٢ فٟٓ، ٖمُ ٚ حىٓ زض ٘ٓبْ فّؿف٣ ثب زضن ضاث١ُ ٚ : اؾت ٌصاض لبٖ٘ٛ پ٥ك٥ٗ ثٝ َٛض ٞب آٖ ز٢ٚ ٞط زض لٜٛ ا٤ٗ وٝ زاضز لّٕطٚ زٚ ا٘ؿبٖ قٙبذت لّٕتط ُ حٛظ٠ زٚ ثب اضتجبٌ زض وٝ اذت٥بض ٔفْٟٛ لّٕطٚ ٚ َج٣ٗ٥ ٔفب٥ٞٓ ُ ٚ ٘ٓتط٢ ٖمت لتطاض ّٖٕت٣ ٖمت ٓ وٕته ثٝ َج٣ٗ٥، ٔفب٥ٞٓ ثٝ ٚؾ١ّ٥ ٌصاض٢ لبٖ٘ٛ. زاض٘س . اؾتت ٘ٓتط٢ ٚ ٥ٌتطز ٔت٣ نتٛضم فٟت ا٤ٗ ضٚ اظ. اؾت ٣ّٕٖ نطفبً ٚ ٥ٌطز ٣ٔ نٛضم ٖمُ ثٝ وٕه اذت٥بض، ٔفْٟٛ ثٝ ٚؾ١ّ٥ ٌصاض٢ لبٖ٘ٛ ٗ ثط ٤ىس٤ٍط، ثب تعاحٓ ثسٖٚ ضا ٔرتّف ٌصاض٢ لبٖ٘ٛ زٚ ٖمُ ٚ فٟٓ ٝ ٚاحتس ؾتطظ٥ٔ َ تزطثت اٖٕتب ٞتب٢ ؾتبحت ٥ٔبٖ ٕٞچ٥ٙٗ ٚ ٖمُ ٚ فٟٓ لٛا٢ ٥ٔبٖ ثعضي قىبف٣ تفى٥ه، ا٤ٗ ثٝ ثٙب. وٙٙس ٣ٔ اٌتط ظ٤تطا .قتٛز پتط تتاؾ الظْ وٝ ستآ٤ ٣ٔ ٛزتثٝ ٚر ىتٔح مُتٖ ٘ٓبْ زض ٣ّٕتٖ ٚ ٙبذت٣تق ٥بضتاذتت ْٟٛتٔفت ٔحؿتٛؼ فتٛق لّٕطٚ ٚ ٗتتَج٥ ٔفْٟٛ ٔحؿٛؼ ٕطٚتلّ ٥ٔبٖ قىبف٣ چ٥ٙٗ وٙتس ٔتحمتك َج٥ٗتت زض ضا ذتٛز قتسٜ ٚيٕ فطا٥ٔٗ ثب٤س ٣ّٕٖ ٖمُ ٞٓ ثبظ ثبقس، تٝتزاق ٚرٛز (. تii ، ز٤جبچٝ ، ،وب٘ت) اظ ٚ زاضز لتطاض َج٥ٗتت ٥ّٖت تحت اؾت، َج٥ٗت ا٥ٖبٖ اظ ٣ٙ٥ٖ وٝ ِحبِ ا٤ٗ اظ ا٘ؿبٖ ْ ٞط اٌطچٝ. وٙس ٣ٔ ُٖٕ ٖمُ ٥ّٖت تحت اؾت، آظاز اضاز٠ ٚ ٖمُ زاضا٢ وٝ رٟت آٖ زٚ اظ وتسا ُ آظاز اضاز٠ ذٛاؾتت وٝ ؾٗبزم حهَٛ أب وٙٙس، ٣ٔ ٌصاض٢ لبٖ٘ٛ ذٛز ٤ٚػ٠ ؾبحت زض ٥ّٖت، ٖمت ٖ َج٥ٗت٣ تٕب٤الم ٚ ٞب ا٥ٍ٘عـ ٥ّٖت ثط اضازٜ ٥ّٖت تؿٍّ ثٝ ٔسز تٟٙب اؾت، ٖ ثتس ُ ا٘ؿتب حبنت زض ا٤ٙزب ٘مف ل٠ٛ حىٓ ثٝ ٖٙٛاٖ ٚاؾ١ُ زٚ ل٠ٛ ز٤ٍتط آغتبظ (. kant, , - )آ٤س ٣ٔ ٣ّٕٖ ٖمُ غب٤بم ٚفك ثط آ٘چٝ ثٝ ٔخبث١ َج٥ٗت ٖبِٓ ثٝ وٝ ؾبظز ٣ٔ لبزض ضا ٔب ل٠ٛ حىٓ قٛز. ٣ٔ .و٥ٙٓ ٘ٓط ٤بفتٝ، تُج٥ك تزطث٣ ٖبِٓ اظ ٔب قٙبذت ثط آ٘چٝ ثٝ ٖٙٛاٖ ٣ّٕٖ ٖمُ ثٝ ٚ اؾت قتٛز ٣ٔ ذٛا٘سٜ ظ٤جب رٟت آٖ اظ ٚقٛز ٘بق٣ ٣ٔ فٟٓ ٚ ذ٥بَ آظاز ٕٞب٣ٍٙٞاظ ظ٤جب أط ٚ وٙس ٣ٕ٘ ُٖٕ ٖمُ ٤ب فٟٓ ٔت٥ٗٗ ٔفْٟٛ ٚ انُ ٌٛ٘ٝ ٥ٞچ تحت ذٛز، ش٣ٙٞ فٗب٥ِت زض ذ٥بَ وٝ / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ ٝ اؾتت ٣ٙ٥ٖ ظ٤جب، ٥ٖٗ اؾبؼ، ا٤ٗ ثط .زٞس ٣ٕ٘ لطاض ذٛز غب٤ت ضا ٔفب٥ٞٓ ا٤ٗ ٖ ٔٛرتت وت تتٛاظ فٟتٓ، لت٠ٛ ثتب آٖ ٕٞتب٣ٍٙٞ ٚ ذ٥بَ ل٠ٛ آظاز فٗب٥ِت اِجتٝ. ٌطزز ٣ٔ فٟٓ ٚ ذ٥بَ لٛا٢ ٥ٔبٖ و٣ّ ٌ فٟٓ ل٠ٛ ٚ ذ٥بَ ل٠ٛ ٥ٔبٖ ٕٞب٣ٍٙٞ أىبٖ ثٝ نطفبً ثّىٝ ٥٘ؿت، قٙبذت٣ ٔمت٥ًبم تبثٕ ٔطثتٛ ٝ ٘بْط وٝ ٥ٖٗ ٚرٛز ثٝ ا٢ ٖاللٝ ثسٖٚ تأ٣ّٔ حىٓ ل٠ٛ .اؾت ُّٔتٛة ٚ وتبضوطز ؾتٛزٔٙس٢، ثت أتط ثتب ٔتفتبٚم ظ٤جتب أتط ،ا٤ٗ ضٚ اظ. زاضز تٛرٝ ٥ٖٗ آٖ ٔحى نٛضم ثٝ نطفبً اؾت، آٖ ثٛزٖ اؾتت، اذاللت٣ غب٤بم ثٝ ٘بْط وٝ ذ٥ط أط ٚ اؾت قره٣ ٖال٤ك ٚ ٞب ا٥ٍ٘عٜ ثٝ ٘بْط وٝ ُٔجٛٔ .( ، ة : ،وب٘ت)زاض٘س تٛرٝ ق٣ء ٚرٛز ثٝ ٕٞٛاضٜ وٝ ثبقس ٣ٔ ا٤ٗ اؾتمالَ زض ظ٤جب٣٤ ٚاثؿتٝ ثط وٕبَ ٔفْٟٛ ٚ شٚل٣ حىٓ ٕٞىبض٢ ثٝ اقبضٜ ثب وب٘ت ثط٘س، أب زض ٥ٖٗ حبَ، ا٢ اظ ٤ىس٤ٍط ٣ٕ٘ وٝ وٕبَ ٚ ظ٤جب٣٤ ٥ٞچ وساْ ثٟطٜ . ثب آٖوٙس ٣ٔ و٥ستأ زٚ قتٛز، ظٔب٣٘ وٝ ثٝ ٚاؾ١ُ ٔف٣ٟٔٛ، تهٛض ٥ٖٗ ثب ٥ٖٗ ت اظ ح٥ج آ٘چٝ وٝ ثب٤س ثبقس ت ٔمب٤ؿٝ ٣ٔ ضيتب٤ت ،اظ ٔٙٓط وب٘تت تٛاٖ اظ ٕٞطا٣ٞ ا٤ٗ ٔفْٟٛ ثب زض٤بفت حؿ٣ زض شٞٗ ذٛززاض٢ وطز. ٣ٕ٘ قٛز، ضيب٤ت٣ زض ٘ؿجت ثب غب٤ت زض٣٘ٚ وٝ أىبٖ آٖ چ٥ع ضا ٔٛرت ٣ٔ ،خطم زض چ٥ع٢حبنُ اظ و فطو ضيب٤ت٣ اؾت وٝ ٥ٞچ ٔف٣ٟٔٛ ضا پ٥ف ،ٔتى٣ ثط ٔفْٟٛ اؾت، أب ضيب٤ت حبنُ اظ ظ٤جب٣٤ پ٥ٛؾتٝ اؾت. حبَ اٌط حىتٓ ،قٛز ٚاؾُٝ ثٝ تهٛض٢ وٝ ٥ٖٗ اظ َط٤ك آٖ زازٜ ٣ٔ ٥ٌطز ٚ ث٣ ٣ٕ٘ ا٤ٗ ٔحتسٚز ٔٛرٛز زض وخطام آٖ ٔم٥س ٚ ثٙبثط ء ٕٞب٘ٙس حىٓ ٖم٣ّ ثٝ غب٤بمثبض٠ ٤ه ق٣شٚل٣ زض ٚ زض ظ٤جتب٣٤ ٚاثؿتتٝ، ضيتب٤ت ،ثبقس، ز٤ٍتط ٤ته حىتٓ شٚلت٣ آظاز ٚ ٔحتى ٥٘ؿتت. اظ ا٤تٗ ض وٙٙتس. زض ٤٣ٔبثٙس ٚ زض ٥ٖٗ حبَ اؾتمالَ ذٛز ضا ٥٘ع حفّ پ٥ٛ٘س ٣ٔ ،ظ٤جبقٙبذت٣ ٚ ضيب٤ت ٖم٣ّ . ٔحى ثتٛزٖ ٔتّٗك زاٚض٢ اؾت ثبض٠ ٥ِٖٗبؾتٝ اظ ٘ٛٔ آٌب٣ٞ ٔب زضذٚالٕ ٥ٔبٖ آٖ زٚ تفى٥ى٣ ثط وٙٙسٜ ٥ٞچ ٔف٣ٟٔٛ اظ غب٤ت ثبض٠ ٤ه ٥ٖٗ، ٌٔٙٛ ثٝ ا٤ٗ أط اؾت وٝ قرم حىٓزض حىٓ شٚل٣ (. ت : ٕٞبٖ، ةوٓ آٖ ضا زض حىٓ ذٛز زض ٘ٓط ٥ٍ٘طز) زض٣٘ٚ ٘ساقتٝ ثبقس ٤ب زؾت ٝ اؾتت ثٝ قتط٣َ ظ٤جب٣٤ٚاثؿتٝ ثٛزٖ وٝ تٛاٖ ٌفت زض ٚالٕ، ٣ٔ غب٤تت ٚ ٔمهتٛز وت ضا ٞتب٣٤ تزطثٝ أىبٖ تمؿ٥ٓ ا٤ٗ ثب وب٘ت. اؾت آظاز ،٘جبقس چ٥ٙٗ اٌط ٚ ثبقس ٘ٓط زض آٖ اظ ذبن٣ زض ٚ ذتبل ٔمهتٛز٢ حهَٛ ٚؾ١ّ٥ ثٝ ٖٙٛاٖ ضا غبئ٥ت ثب ٔمطٖٚ وُ ٞب آٖ زض وٝ وٙس ٣ٔ ِحبِ ا٤ٗ ث٥ٗ ٌصاقتٗ ت٥٥ٕعثب٤س ثٝ ا٤ٗ أط تٛرٝ زاقت وٝ .و٥ٙٓ ٣ٔ ٔمهٛز زضن آٖ اظ رسا حبَ ٥ٖٗ ٔمطٖٚ وُ اظ ٔرتّف زضن لؿٓ زٚ ث٥ٗ تٕب٤ع٢ ثّىٝ ٥٘ؿت، اق٥بء ثٙس٢ ضزٜ ثطا٢ ،ظ٤جب٣٤ ٘ٛٔ زٚ ٥ٖٗ ٤ه ثّىٝ ٘ساضز، ٚرٛز شات٣ ثٝ ٘حٛ ٚاثؿتٝ ٚ آظاز ظ٤جب٢ ا٥ٖبٖ ٘بْ ثٝ چ٥ع٢ٚ غبئ٥ت اؾت ثٝ ٓ ٚ آظاز ظ٤جب٣٤ ثٝ ٖٙٛاٖ ٞٓ تٛا٘س ٣ٔ ٔتٗ ٚ ٔتأُٔ ؾٛغ٠ آٌب٣ٞ ٔجٙب٢ ثط ٖ ٞت ظ٤جتب٣٤ ثتٝ ٖٙتٛا ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ وتٝ ثب آٖ ،اظ ٔٙٓط وب٘تاِجتٝ ثب٤س تٛرٝ زاقت وٝ .(guyer, , قٛز) زاٚض٢ ٚاثؿتٝ ٔب٤ُ اؾت ا٥ٖبٖ ضا ثتط ٔجٙتب٢ ،وٙٙس٠ ٘ٛٔ ظ٤جب٣٤ ا٥ٖبٖ اؾت، أب ٕٔٗٛالً شٞٗ ت٥٥ٗٗ ،زاٚض٢ شٞٗ ٤طا ل٠ٛ ذ٥بَ زض ٔٛار١ٟ ا٥ِٚتٝ ثتب ٖت٥ٗ زض تأٔتُ ظ٤جبقتٙبذت٣، ظ .َطحكبٖ ٔٛضز زاٚض٢ لطاض زٞس ا٤ٗ تٛرٝ شٞٗ ثٝ وٕبَ ي٥ٕٕٝ قسٜ ثٝ قٛز. ثٙبثط ضم ٔحى( ٥ٖٗ ٔٛارٝ ٣ٔ٘رؿت ثب َطح )نٛ ٥ٌتطز. ٥ٖٗ ظ٤جب زض ظ٤جب٣٤ ٚاثؿتٝ، ٕٞٛاضٜ پؽ اظ تٛرٝ ثٝ ٖٙهط نٛض٢ ٔٛرٛز زض ٥ٖٗ ا٘زبْ ٣ٔ ٝ وٕتط٢ ذّٛل ٚاثؿتٝ، ظ٤جب٣٤ حىٓقٛز وٝ ا٤ٗ أط ؾجت آٖ ٣ٔ ٓ ٘ؿتجت ثت آظاز ظ٤جتب٣٤ حىت ٝ وبضوطز ٤ب ٔٗٙب اظ وٝاؾت ٚ ذبِم ا٤ٗ حىٓ ثطا٢ وؿ٣ ٔحىظ٤طا .زاقتٝ ثبقس ٔكتبٞسٜ آ٘چت ثط ٔجٙب٢ ٘متف ٔحتٛض٢ تٛاٖ ٌفت وٝ ٘ٛٔ ظ٤جب٣٤ زض ٘ت٥زٝ ٣ٔ .ثبقس ٘ساقتٝ ازضاو٣ ٥ٞچ ،وطزٜ ؛ ثٝ ا٤ٗ نٛضم وٝ اٌط ؾٛغٜ ٔتأُٔ نطفبً ثٝ احؿبؼ ِصم ش٣ٙٞ ذٛز قٛز ت٥٥ٗٗ ٣ٔ ،ؾٛغ٠ ٔتأُٔ ظ٤جب٣٤ آظاز، ٚ اٌط ا٤ٗ احؿبؼ ضا ثب ٔفْٟٛ وٕبَ ٥ٖٗ ٕٞتطاٜ ؾتبظز، ظ٤جتب٣٤ ٚاثؿتتٝ ثؿٙسٜ وٙس، قٛز. زاٚض٢ ٣ٔ آل زیبایی ایدٌ (٣توبفتت طٌتقتت) ٥ب٣٘تثتت لبثتتُ ٖٕتت٣ٔٛ ٥بضتٔٗتت ٞتتط ٥بةتغتت زض ت،توب٘تتط تٔٙٓتتاظ (sufficient condition) ثتٝ ٚ ثبضظ ٞب٢ ٕ٘ٛ٘ٝ اظ قٕبض٢ ثب٤س ،ٔفْٟٛ ٤ه ثٝ وبض٥ٌط٢ ثطا٢ ٚ ثتطآٚضز اضظ٤تبث٣، زض ٚ وتطزٜ تّم٣ پب٤ب٣٘ حس ثٝ ٖٙٛاٖ ضا ٞب آٖ ٚ وطز قٙبؾب٣٤ ضا رٙزبَ اظ زٚض ٥ٌط٤ٓ. شٚق ثب٤س ٞب ضا ثٝ ٖٙٛاٖ اٍِٛ زض ٘ٓط ٣ٔ ثط ا٤ٗ اؾبؼ، ثطذ٣ اظ ٕ٘ٛ٘ٝز٥ٞٓ. زذبِت زاٚض٢ قتٛز وتٝ ا٢ قره٣ ثبقس ٚ زض ٘ٓط ٌطفتٗ ا٤ٗ اٍِٛ ثطا٢ زاٚض٢ ظ٤جبقٙبذت٣ ؾجت آٖ ٕ٘ت٣ لٜٛ ثطز، شٚق ثب تم٥ّس اظ ز٤ٍطاٖ اوتؿبة قٛز. وؿ٣ وٝ زض زاٚض٢ ظ٤جبقٙبذت٣ ذٛز اظ ا٣٤ٍِٛ ثٟطٜ ٣ٔ ، وٙتس ٕٞت٥ٗ اٍِتٛ زاٚض٢ ٔت٣ زضثبض٠تب رب٣٤ وٝ ٣ زض ا٤ٗ أط زاقتٝ ثبقس ٚ اِجتٝثب٤س ٟٔبضم وبف ُ شٚق ٘كبٖ زازٜ اؾت. ثط ا٤ٗ اؾبؼ، وب٘ت ٘ت٥زٝ ٣ٔ شٚق (archetypeاٖتال٢) ٥ٌطز وٝ ٔخت ثط اؾتبؼ آٖ ٚ وٙس ا٤زبز ذٛزـ زض ضا آٖ وؿ٣ يطٚض٢ اؾت وٝ ٞط ٚ ثبقس نطف ا٢ ا٤سٜ ثب٤س (. ، ، ة وب٘ت، )زاٚض٢ وٙس ذٛز شٚق حت٣ ٚ شٚق تٛؾٍ زاٚض٢ شٚق، ضارٕ ثٝ ٔتّٗك قت٣ء ٤تب ض٤ٚتساز آ٤ب وٝ قٛز ٣ٔ ُٔطح پطؾف ا٤ٗ تأ٣ّٔ احىبْ زضثب زض ٘ٓط ٌطفتٗ ا٤ٗ ُّٔت، ٝ اؾت وبض٢ ا٤ٗ ٚ ذ٥ط، ٤ب اؾت ٘عز٤ه آَ ا٤سٜ أط ثٝ ذبل ْ ثب٤تس ٔتب وت نتسق اضظ٤تبث٣ ٍٞٙتب ٤تب ؾرٗ ٣ٖٛ٘ ٔفْٟٛ اظ ٖبْ ٔٛضز ٣ٖٛ٘ ثبظٕ٘ٛز وب٘ت، ٔٙٓط اظ آَ ا٤سٜ ز٥ٞٓ. ٤ه ا٘زبْ ٞب ٌعاضٜ ُ ٔف٣ٟٔٛ ٥٘ؿت لبزض ٚال٣ٗ چ٥ع ٥ٞچ ظ٤طا .اؾت ٥٘بفت٣ٙ تحمك لَٛ ثتطا٢ .ثركتس تحمتك ضا وبٔت / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ آَ ا٤تسٜ ذتسا ٤تب اؾت حىٕت آَ ا٤سٜ ١ٕ٘ٛ٘ ،ؾمطا٣َ فطظا١٘ ا٘ؿبٖ ،«ٔحى ٖمُ ٘مس» زض ،ٕ٘ٛ٘ٝ kant, , a / b and a / b .) )اؾت ٔحى ٖمُ اؾتٗال٣٤ آَ ظ٤جتب٣٤، ٘ت٣ٖٛ اظ ظ٤جتب٣٤ ضا قب٤ؿتت١ ضؾت٥سٖ ثتٝ ا٤تسٜ وب٘ت زض ضاثُٝ ثب چ٣ٍٍ٘ٛ ٔٙس٢ ٣ٙ٥ٖ حجٛم ٤بفتٝ ثبقتس. زض زا٘س وٝ ٔجٟٓ ٘جبقس ٚ ثط اؾبؼ ٔف٣ٟٔٛ اظ غب٤ت ٚرٛ ٣ٔ رؿت شٚلت٣ حىٓ ٤ه ٔتّٗك ثٝ ثّىٝ ٔحى، وبٔالً شٚل٣ حىٓ ٤ه ٔتَّٗك ثٝ ٘ت٥زٝ، ا٤ٗ ظ٤جب٣٤ ٘جب٤س آٖ زض آِت٣ ا٤سٜ ثب٤س وٝ زاٚض٢ ٔجٙب٢ ٘ٛٔ ٞط قبِٛز٠ زض ٣ٙٗ٤. ثبقس زاقتٝ تّٗك ،قسٜ ٖم٣ّ لؿٕبً غب٤ت٣ پ٥ك٥ٗ، ثٝ ٘حٛ وٝ ثبقس زاقتٝ لطاض ٥ٗٔٗ ٔفب٥ٞٓ ثب ٔٛافك ٖم٣ّ ا٤س٠ ٣ٖٛ٘ ثب٤س قٛز، ٤بفت آَ ثتطا٢ غ٥تط اظ ا٤ٗ ضٚ، اٚ تهٛض ا٤سٜ وٙس. ٣ٔ ت٥٥ٗٗ اؾت ٔتى٣ آٖ ثط ٣ٙ٥ٖ زض٣٘ٚ أىبٖ وٝ ضا قبٖ ثٝ لتسض ٞب٢ ظ٤جب ٤ب ٔؿى٣ٙ ظ٤جب، غب٤ت زض أٛض٢ ٕٞچٖٛ ٌُ ظ٤طا. زا٘س ا٘ؿبٖ ضا ٘بٕٔىٗ ٣ٔ ٞب تمط٤جتبً ٕٞب٘ٙتس ٔٙس٢ زض ٔٛضز آٖ وبف٣ ثٝ ٚؾ١ّ٥ ٔفب٥ٞٓ ت٥٥ٗٗ ٚ تخج٥ت ٘كسٜ ٚ زض ٘ت٥زٝ غب٤ت ظ٤جب٣٤ ٔجٟٓ، غ٥طپ٥ك٥ٗ ٚ آظاز اؾت. زض ز٤سٌبٜ اٚ، تٟٙب ٔٛرٛز٢ وٝ غب٤ت ٚرٛزـ ضا زض ذٛزـ تٛا٘س ا٤ٗ غب٤بم ضا ثب وٕته ٖمتُ ت٥ٗت٥ٗ وٙتس. ٕٞچٙت٥ٗ ا٤تٗ ت. ا٘ؿبٖ ٣ٔزاضا اؾت، ا٘ؿبٖ اؾ ٞب ضا ثب غب٤بم شاتت٣ ٚ ٞب٢ ذبضر٣ زض٤بفت وٙس، ثبظ ٞٓ آٖ ٞب ضا اظ ازضان تٛا٘ب٣٤ ضا زاضز وٝ اٌط آٖ ٞب ضا ثٝ ٘حٛ ظ٤جبقٙبذت٣ ٔٛضز زاٚض٢ لطاض زٞتس. ثتط ا٤تٗ اؾتبؼ، و٣ّ ل٥بؼ وٙس ٚ ٕٞب٣ٍٙٞ آٖ تٛاٖ ٘ت٥زٝ ٌطفت وٝ زض ٥ٔبٖ اقت٥ب٢ ٔٛرتٛز زض رٟتبٖ، وٙس وٝ ٣ٔ ضا ث٥بٖ ٣ٔ وب٘ت ا٤ٗ ُّٔت (. - : آَ ظ٤جب٣٤ اؾت)وب٘ت، ا٤سٜتٟٙب ا٘ؿبٖ ٔؿتٗس ٤ه حتساوخط ٤تب وبُٔ ظ٤جب٣٤ ٕ٘ب٤ف ثطا٢ آٖ لبث٥ّت ٚ ا٘ؿبٖ آَ ا٤سٜ ٥ٔبٖ ا٢ ضاثُٝ چٝ أب وٝ اؾت ٟ٘فتٝ ٚاثؿتٝ ظ٤جب٣٤ اظ اٚ تّم٣ زض وب٘ت ٤بفت؟ پبؾد تٛاٖ ٣ٔ ظ٤جب٣٤ اظ ثٛزٖ ثطذٛضزاض ٤ب ا٢ ٘م٥هٝ وٝ آٖ ثٝ قطٌ ٞؿتٙس، ظ٤جب( ا٘ؿبٖ َج٥ٗتبً ٚ و٥ّؿب ذب٘ٝ، ٔب٘ٙس) ٔٙس غب٤ت چ٥عٞب٢ آٖ زض آٖ َطاحت٣ زض ا٤تطاز٢ وٝ آٖ ثٝ قطٌ اؾت ظ٤جب و٥ّؿب تطت٥ت ا٤ٗ ثٝ ٘جبقس؛ ٞب آٖ ٔٙس٢ زض غب٤ت تٛا٘تس ٕ٘ت٣ فبحكت٣ ٘م٥هت١ ٞت٥چ وٝ وٙس ٣ٔ تهٛض وب٘ت ا٘ؿبٖ، ٔٛضز زض .٘كٛز ٔب ٥٘ب٤ف اظ ٔبٕ٘ قتٛز، ٣ٔ آقىبض ٞب ا٤ٗ ٔب٘ٙس ٚ چٟطٜ ضفتبض، ُٖٕ، زض فطز اذالل٣ وٕبَ وٝ ٌٛ٘ٝ آٖ ضا ظ٤جب ِحٓبم ٝ فطز٢ وٝ ٥٘ؿت ٔٗٙب ثساٖ اِجتٝ ا٤ٗ .وٙس زاض ذسقٝ ٓ ظ٤جتب اِعأتبً اؾتت، اذتالق اؾت٠ٛ وت ثتسا٥٘ (savile, , .) وب٘ت زض ازا١ٔ تج٥ت٥ٗ ٔتالن زاٚض٢ ظ٤جبقتٙبذت٣ ثتط اؾتبؼ ٤ته زا٘س آَ، ٖالٜٚ ثط ا٤س٠ ٖم٣ّ، ا٤س٠ ٔتٗبضف ظ٤جبقٙبذت٣ ضا ثطا٢ زاٚض٢ ظ٤جبقٙبذت٣ يطٚض٢ ٣ٔ ا٤سٜ ٝ (. ا٤س٠ ٔتٗبضف ظ٤جبقٙبذت٣ قٟٛز٢ ٔٙفطز اظ ل٠ٛ ذ٥بَ اؾتت ت ، ة ، وب٘ت،) وت ا٤تس٠ . وٙتس ٣ٔ ٔتهٛض ضا ذبل ح٥ٛا٣٘ ٘ٛٔ ثٝ ٔتّٗك چ٥ع٢ ثٝ ٔخبث١ ا٘ؿبٖ زضثبض٠ ٔب زاٚض٢ ٥ٗٔبض ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ زض ٔٙتس٢ غب٤ت تط٤ٗ ثعضي - قٛز ٣ٔ اؾتفبزٜ ظ٤جبقٙبذت٣ زاٚض٢ و٣ّ ٥ٗٔبض ٖٙٛاٖ ثٝ وٝ - ٖم٣ّ اظ - اؾتت تهٛض لبثُ ٔٛرٛز٢ ٞط ثطا٢ وب٘ت ز٤سٌبٜ زض وٝ - ٔتٗبضف ا٤س٠ ٚ اؾت ق٣ء نٛضم ٍ ،ٔتٗتبضف ا٤س٠. قٛز ٣ٔ اؾترطاد ا٘ؿبٖ ٕٞچٖٛ ٘ٛٔ ٤ه ذبل ٖٙبنط ٚاؾ١ُ ثٝ ٚ تزطثٝ تٛؾت ٕ٘ٛ٘ٝ، لت٠ٛ ثطا٢. آ٤س ٣ٔ پس٤س ٤ىس٤ٍط ض٢ٚ ثط تهب٤ٚط زازٖ لطاض ثب ٚ ٘بآٌبٞب٘ٝ ق٠ٛ٥ ثٝ ذ٥بَ ل٠ٛ زٞس ٚ حسّ ٚؾٍ ٤ب ٥ٔتب٣ٙ٥ٍ٘ اظ آٖ ضا ثتٝ زؾتت تهب٤ٚط ٞعاض ٔطز ثبِغ ضا ض٢ٚ ٞٓ لطاض ٣ٔ ،ذ٥بَ قٛز ٚ تحت ٞط قطا٤ٍ تزطث٣ ٔتفبٚت٣ ثٝ ٤ه نٛضم حبنُ ٣ٔ ،آٚضز. اِجتٝ، ا٤ٗ ا٤س٠ ٔتٗبضف ٣ٔ ضؾٙس. أب چٍٛ٘ٝ زاٚض٢ ثط ا٢ ثٝ ا٤س٠ ٔتٗبضف ٔرتم ثٝ ذٛز ٣ٔ زض ا٤ٗ پطٚؾٝ ٞط وكٛض ٤ب ربٔٗٝ ضٚز. پبؾد زض ا٤ٗ ٔٙس٢ ٣ٙ٥ٖ زاضز، زاٚض٢ ظ٤جبقٙبذت٣ ثٝ قٕبض ٣ٔ آَ وٝ ٘ٓط ثٝ غب٤ت ؾبؼ ا٤سٜا يطٚض٢ اؾت: ا٤تس٠ ٔتٗتبضف ظ٤جبقتٙبذت٣ ٚ ،آَ ظ٤جب٣٤ أط ٟ٘فتٝ اؾت وٝ زٚ چ٥ع زض ٕ٘ب٤ف ا٤سٜ ٙتب٢ رب٣٤ وٝ ا٤س٠ ٔتٗبضف ٔحهَٛ ل٠ٛ ذ٥بَ ٚ ثبظ٢ آظاز آٖ ثب ل٠ٛ فٟتٓ ثتط ٔج ا٤س٠ ٖم٣ّ؛ اظ آٖ ضٚز. رٕٕ ٥ٔبٖ ا٤ٗ نٛضم شٚل٣ ٔحى ٞب٢ تزطث٣ اؾت، نٛضم شٚل٣ ٔحى ثٝ قٕبض ٣ٔ زازٜ ٝ ثب٤تس آَ وب٘ت، ا٤سٜ ز٤سٌبٜ وٙس. زض آَ ظ٤جب٣٤ ضا زاضا٢ اضظـ ظ٤جبقٙبذت٣ ٣ٔ ٚ ا٤س٠ ٖم٣ّ، ا٤سٜ ثت ٗ ٚ وٙس ت٥٥ٗٗ ٔكرهبً ت زاض٤ٓ ضا آٖ ظ٤جب٣٤ زاٚض٢ لهس وٝ تضا ق٣ء وٕبَ وٝ ثبقس ا٢ ٌٛ٘ٝ ا٤ت قتٛز ؾجت اؾت ٕٔىٗ وٝ ٞب٣٤ زِجؿت٣ٍ ؛اؾت آٖ ثٝ ٔب ٌصضا٢ ٞب٢ زِجؿت٣ٍ اظ ٔؿتمُ ت٥٥ٗٗ، آَ ظ٤جب٣٤ ثطا٢ وب٘ت ثتط اؾتبؼ ا٥ٕٞت ا٤سٜ .ثبق٥ٓ زاقتٝ ق٣ء وٕبَ زضثبض٠ ٔتفبٚت٣ ٞب٢ زاٚض٢ ٞب٢ حؿ٣ ق٣ء ثتب ضيتب٤ت زٞس ربشثٝ آَ ظ٤جب٣٤ اربظٜ ٣ٕ٘ زضؾت٣ آٖ اؾت؛ ثٝ ا٤ٗ ٔٗٙب وٝ ا٤سٜ قٛز، زاٚض٢ ُٔبثك ثتب ٔٙس٢ ق٣ء ِحبِ ٣ٕ٘ رب٣٤ وٝ نطفبً غب٤ت حبنُ اظ آٖ زضآ٥ٔعز. أب اظ آٖ ٌتبٜ زاٚض٢ ُٔتبثك ثتب ٚ زض ٘ت٥زتٝ ٞت٥چ ا٤ٗ ٥ٗٔبض ٞطٌع ٤ه لًبٚم ظ٤جبقٙبذت٣ ٔحى ٥٘ؿت اِجتٝ، ا٤ٗ أط ؾتجت آٖ (. ، ة ، وب٘ت،)٥٘ؿت آَ ظ٤جب٣٤ ٤ه حىٓ شٚل٣ نطف ا٤سٜ شٚل٣ ثٝ قتٕبض ٥٘ب٤تس. اظ آَ زاٚض٢ ظ٤جبقٙبذت٣ ٘جبقس ٤ب حىٓ قٛز وٝ زاٚض٢ ُٔبثك ٤ه ا٤سٜ ٣ٕ٘ ٗ ن ٚ ٥ٗٔتبض ٔٙبؾتت ثتتطا٢ زاٚض٢ ٌكتتب٢ ٤تبفتٗ ٔتال ضاٜ ،آَ ظ٤جتب٣٤ ضٚ زاٚض٢ ُٔتبثك ا٤تسٜ ا٤ت ظ٤جبقٙبذت٣ اؾت. ٖ آَ ظ٤جتب٣٤، قتب٤س ا٤سٜ زضثبض٠ثب تٛرٝ ثٝ ز٤سٌبٜ وب٘ت ٘ت٣ٖٛ زاض رب٘تت ضا وب٘تت ثتتٛا حطف ا٤ٗ اظ ٔطاز. اؾت غ٥طظ٤جبقٙبذت٣ ٖٛأُ زذبِت ٥٘بظٔٙس وٝ زا٘ؿت افال٣َ٘ٛ قجٝ ظ٤جبقٙبؾ٣ ا٘تعاٖت٣ ٚرتٛز٢ ثٝ ٔٙس ٖاللٝ ٤ب ظ٤جبقٙبذت٣ حس تب اذالل٥بم تم٥ُّ زاض رب٘ت وب٘ت وٝ ٥٘ؿت ا٤ٗ زض وب٘تت، ٔٙٓتط اظ ثّىٝ اؾت، ظ٤جب٣٤ ٔطاتت ؿّٝؾّ ٣ٖٛ٘ ٔسافٕ ٤ب ظ٤جب٣٤ اٖال٢ ٔخبَ ٕٞچٖٛ .قتٛز ٣ٔ حبنُ ٔتٗسز ٚ ٔٙفطز اق٥ب٢ اظ ٔب تزطث١ زض ٔؿتم٥ٕبً اذالل٣ ذ٥ط ٔب ظ٤جبقٙبذت٣ تزطث١ / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ ٝ آٚضز ثتٝ قتٕبض اق٥ب٣٤ اَٚ تطاظ ٤ٚػ٣ٌ ٤ب نفت ٣ٖٛ٘ حىٓ زض ضا ظ٤جب٣٤ ٘جب٤س اٚ، ٔٙٓط اظ زض وت ٝ ٔتّٗك نفت٣ ٤ب ٤ٚػ٣ٌ ضا ظ٤جب٣٤ اؾت ثٟتط ثطٖىؽ زاض٘س؛ رب٢ ا٢ رساٌب٘ٝ ظ٤جبقٙبذت٣ لّٕطٚ ثت تتطاظ اذاللت٣ ٤ٚػٌت٣ ٤ب نفت وٝ قٛز ٣ٔ ز٤سٜ چ٥عٞب٣٤ ١ٕٞ زض وٝ و٥ٙٓ لّٕساز ٔتٗب٣ِ تطاظ٢ (.savile, , )زاض٘س ذٛز ْبٞط زض حساوخط ثٝ ضا اَٚ آل زیبایی با زیبایی يابستٍ وسبت ایدٌ آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ ضا ثب٤س ثب ظ١ٙ٥ٔ زغسغ١ اذالل٣ وب٘ت ثطضؾ٣ وطز. اضتجبٌ ا٤سٜ اظ وٝ ٤بثس زؾت ٖبِٓ ثب ا٘ؿبٖ ضاث١ُ اظ تفؿ٥ط٢ ثٝ ذٛز ظ٤جب٣٤ فّؿف١ َط٤ك اظ تب وٛقس ٣ٔ وب٘ت ٝ اؾت ظ٤جبقٙبذت٣ حىٓ ا٤ٗ اٚ، ز٤سٌبٜ زض. ثبقس آظاز ٘ٓطٌبٞف ٔحسٚز٤ت ٝ ضا ٔتب وت زض٤بفتت ثت تأ٥٤تس ٚ ثركتس ٔت٣ ٔحتتٛا زض٤بفت ا٤ٗ ثٝ ٣ّٕٖ ٖمُ وٝ حب٣ِ زض .وٙس ٣ٔ ٞسا٤ت اؾتٗال٣٤ ٖبِٓ ٗ وٝ وٙس ٣ٔ ٕ زض اقت٥بء، اظ ٘ٓطٌتبٜ فبلتس ث٥تٙف ٤ته اظ آٌتب٣ٞ ا٤ت اؾتت ذتسا اظ آٌتب٣ٞ ٚالت (scruton, , - .) پ٥ٛ٘تس اظ اؾتت ٖجبضم ،وب٘ت ا٤ٗ ثبٚض٘س وٝ ٞسفثطذ٣ ثط زض ٚ َج٥ٗت٣ اٍ٘بض٢ غب٤ت ٔفْٟٛ ثب َج٣ٗ٥ اق٥ب٢ شٚل٣ ٚ حؿ٣ زضن زض ٕ٘ب٤بٖ ٕٞب٣ٍٙٞ زازٖ زضثتبض٠ ٞتب آٖ ثٝ وٕه وٝ ٞب٣٤ ضاٜ ثب و٣ّ ثٝ َٛض َج٥ٗت غب٣٤ ٕٞجؿت٣ٍ ؾبذتٗ آقىبض ٘ت٥زٝ، ذٛز لٛم ثٝ ٕٞچٙبٖ ٔٛضز ا٤ٗ زض اٚ اثٟبْاِجتٝ . و٥ٙٓ ٣ٔ ثطلطاض ضاثُٝ آٖ ثب ٚ ا٘س٤ك٥ٓ ٣ٔ َج٥ٗت ٚ ؾتبظ٘سٜ رٙج١ ٖٕالً اؾت ٕٔىٗ ٤ب زاضز وٙٙسٜ ت٥ٓٙٓ رٙج١ نطفبً پ٥ٛ٘س٢ چ٥ٙٗ آ٤ب وٝ اؾت ثبل٣ ٓ ٚ ٞٙط اٚ، ٔٙٓط اظ. اؾت اَٚ ثطزاقت ثٝ ث٥كتط وب٘ت تٕب٤ُ ٚ ثبقس زاقتٝ ٥٘ع زٞٙسٜ لٛاْ ٚؾتب٣ّ٤ ّٖت ثتب رتبٖ، آظازٌت٣ پطٚض٘س٠ ٕٞچٖٛ ٞٙط ٚ( bowie, , and )ا٘س ٖمُ پطٚضـ ثطا٢ ـ ثتطا٢ ا٢ ظ٥ٔٙٝ ٢ٛٙٗٔ، ث٥ٙبز اظ ٔب آٌبٞب٘سٖ ثب ٚ پطٚضز ٣ٔ ضا ٕٞس٣ِ ضٚح ظ٤جب٣٤، زازٖ ٘كبٖ پتص٤ط ازضان ٤ته ظ٤جتب٣٤ احؿبؼ اؾت ٚ ذ٥ط اظ ٕ٘بز٢ ذٛز ظ٤جب ٌطزز. اظ ا٤ٗ ضٚ، أط ٣ٔ اذالل٣ ٞب٢ ا٤سٜ زاضز ٚرتٛز تطو٥ج٣ ا٢ ضاثُٝ ثّىٝ ٘ساضز، ٚرٛز ظ٤جب ٚ ذ٥ط ٥ٔبٖ تح٣ّ٥ّ ا٢ ضاثُٝ ٚ ٥٘ؿت ذ٥ط اظ ٖبض٢ ٓ ذٛة وٝ ؾبظز ٣ٔ ٔؿتٗس ضا ٔب ظ٤جب أط ثٝ تٕب٤ُ آٖ َجك ثط وٝ ُ ) ثبقت٥ ْ ذ٥تط ٖٕت ٓ ا٘زتب ٚ( زٞت٥ (.deleuze, , - and körner, , ؾتبظز) ٣ٔ ٔمسض ثطا٤ٕبٖ ضا اذالق َ ٤ب اٖتال ٕٞبٖآَ ظ٤جب٣٤، ٙٛاٖ تٟٙب ٔهساق ا٤سٜٖثٝ ا٘ؿبٖ ٔٙس٢ غب٤ت . اؾتت اٚ اذاللت٣ وٕتب ٝ وٙت٥ٓ، تهتٛض ٔتتعٔ ٚ ٔزطز چ٥ع٢ ٘جب٤س ضا ٔٙس٢ غب٤ت ا٤ٗ نٛضم ٤ب قىُ زض ضا آٖ ثب٤تس ثّىت ٓ ٖجبضم ز٤ٍتط ثٝ قٛز؛ ٣ٔ ْبٞط آٖ َط٤ك اظ اذالل٣ وٕبَ وٝ ثسا٥٘ٓ پٛقك٣ حىٓ ُ رؿت ٔحت . قتب٤س (savile, , , footnote )اؾتت اذالل٣ وٕبَ ٔحؿٛؼ ْٟٛض ٚ ثطٚظ ثتٛاٖ اظ ا٤ٗ ُٔبِت چ٥ٙٗ ٘ت٥زٝ ٌطفت وٝ ٞسف وب٘ت اظ ٚاضز وطزٖ ٔفْٟٛ ظ٤جب٣٤ ٚاثؿتتٝ ٚ زض ا٘س، پط وتطزٖ ذتن ٘ٓتبْ ظ٤جبقٙبؾت٣ ٔٙس٢ ٣ٙ٥ٖ آَ ظ٤جب٣٤ وٝ ٞط زٚ ٔجت٣ٙ ثط غب٤ت پ٣ آٖ ا٤سٜ ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ سٖ ثٝ ا٢ٍِٛ اذالل٣ زض لبِت آحبض ٞٙتط٢ اؾتت. ٔجت٣ٙ ثط حىٓ شٚل٣ ٔحى زض رٟت ٔٙت٣ٟ ق وٙتس ٔت٣ ث٥بٖ نط٤حبً ،(critique of judgment«)حىٓ ل٠ٛ ٘مس» رف ث زض ذٛز وب٘ت ٖ قتجبٞت ٕٞبٖ ٤ب ٕٔبحّت وٝ اؾت ثط ا٤ٗ ثبٚض اٚ. اؾت اذالل٣ ذ٥ط ٕ٘بز ظ٤جب٣٤ وٝ ْ ٥ٔتب احىتب آظاز٢ ٚ زاض٘س و٥ّت ازٖب٢ زٚ ٞط ٥٘ؿتٙس، تٕب٤الم ثط ٔجت٣ٙ زٚ ٞط) اذالل٣ احىبْ ٚ ظ٤جبقٙبذت٣ اذاللت٣ ذ٥تط ٘كتب١٘ ٤تب ٕ٘بز ضا ظ٤جب٣٤ وٝ وٙس ٣ٔ ٞسا٤ت أط ا٤ٗ ثٝ ضا ٔب( زٚ زذ٥ُ اؾت ٞط زض ٝ ٖم٥تسٜ ا٤ٗ وٝ زاقت تٛرٝ ثب٤س .( ت ، ة ، ثسا٥٘ٓ )وب٘ت، ٝ ٞت٥چ ثت ٔحتى ٚرت ٔٙتس٢ غب٤تت ٚ فطْ ِحبِ ثٝ تٟٙب اثتسا ٔب. ؾبظز ٣ٕ٘ زاض ذسقٝ ضا شٚل٣ حىٓ ثٛزٖ ّٖمٝ ث٣ ٚ ثٛزٖ ٌط ث٥بٖ ظ٤جب أط وٝ ق٤ٛٓ ٣ٔ ٔتٛرٝ زاٚض٢ اظ پؽ ٔطح١ّ زض ٚ زا٥٘ٓ ٣ٔ ظ٤جب ضا چ٥ع٢ غب٤ت، ثسٖٚ وٙت٥ٓ، ٔت٣ اضظ٤بث٣ ظ٤جب ضا ظ٘جم٣ ٌُ وٝ ا٤ٗ اظ پؽ ٕ٘ٛ٘ٝ، ثطا٢. اؾت اذالل٣ ٔفب٥ٞٓ غ٥طٔؿتم٥ٓ ثتب ضا ٞٙتط٢ ٤تب َج٥ٗت٣ ظ٤جب٢ زا٥٘ٓ. ثط ا٤ٗ ٔجٙب، اق٥بء ٣ٔ ٔٗه٥ٔٛت ا٤س٠ اظ ث٥ب٣٘ ضا آٖ ؾف٥س٢ ٤تب ٞتب ؾبذتٕبٖ ثطذ٣. اؾت قسٜ ٌطفتٝ اذالل٣ ٞب٢ زاٚض٢ اظ ْبٞطاً وٝ و٥ٙٓ ٣ٔ تٛن٥ف نفبت٣ ٓ ٔت٣ ٘بْ ،ٔال٤ٓ ب٤ ٘ز٥جب٘ٝ ٤ب ٔت٥ٗ ضا ٞب ضً٘ ثطذ٣ حت٣٘ب٥ٔٓ؛ ٣ٔ آثطٚٔٙس ضا زضذتبٖ . ظ٤تطا زٞت٥ شٞٗ زض اذالل٣ ٞب٢ زاٚض٢ ٘ت٥ز١ زض وٝ و٥ف٥ت٣ قج٥ٝ چ٥ع٢ حب٢ٚ ا٥ٍ٘ع٘س ثط٣ٔ ٔب زض احؿبؾبت٣ وٙس ٣ٔ ٚال٥ٗت ا٤ٗ ثٝ اقبضٜ ،أط ا٤ٗ تٛر٥ٝ ثطا٢ وب٘ت (.körner, , )آ٤س ٣ٔ پس٤س ٚ ض٢ٚ، ٥ٕٞٗ اظ ٚ ثجركس تزؿٓ ،ٖبِٓ زض ضا ذٛز ٞب٢ ا٤سٜ زاضز زٚؾت ٖمُ وٝ ٞٙتط ضا َج٥ٗتت .٤بثس ٣ٔ ذٛز ٞب٢ ا٤سٜ ٔؿتم٥ٓ غ٥ط ث٥بٖ ثطا٢ ثؿتط٢ آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ ت وٝ ٞط وتساْ ثط اؾبؼ آ٘چٝ ٌفتٝ قس، ٥ٔبٖ زٚ ٔفْٟٛ ا٤سٜ ٞب٣٤ ٤بفت ٞب ٚ تفبٚم ٌصاض٘س ت قجبٞت ٞب٢ ٖم٣ّ( ضا ثٝ ٕ٘ب٤ف ٣ٔ ثٝ ٘ح٢ٛ غب٤بم اذالل٣ )ا٤سٜ ٔٙس٢ ٣ٙ٥ٖ زض٣٘ٚ اؾت ٚ ٔفٟت٣ٔٛ غب٤تقٛز. زض ٞط زٚ ٔفْٟٛ، زاٚض٢ ظ٤جبقٙبذت٣ ثط ٔجٙب٢ ٣ٔ قتٛز. ا٤تٗ ٌطفتتٝ ٔت٣ فتطو ثتطا٢ زاٚض٢ پت٥ف آٖ ثب ٔٛافك ٥ٖٗ وٕبَ ٚ ٥ٖٗ چ٥ؿت٣ ثط زاَ آَ ظ٤جب٣٤، ٔفْٟٛ حبنُ اظ رٕٕ ا٤س٠ ٖمّت٣ ٚ فطو زض ظ٤جب٣٤ ٚاثؿتٝ، وٕبَ ٥ٖٗ ٚ زض ا٤سٜ پ٥ف ث٥ط٣٘ٚ ٣ٙ٥ٖ زٚ ٔفْٟٛ غب٤بم وساْ اظ ا٤ٗ ا٤س٠ ٔتٗبضف ظ٤جبقٙبذت٣ اؾت. اظ ٥ٕٞٗ رٟت، زض ٥ٞچ ٗ قتٛز. زاذتُ ٕ٘ت٣ (ؾٛزٔٙس٢ ٤ب ا٥ٖبٖ ز٤ٍط ثب ٥ٖٗ ذبضر٣ ٘ؿجت) ٞتط زٚ زاضا٢ اضظـ ثٙتبثطا٤ ظ٤جبقٙبذت٣ ٞؿتٙس، أب ثب ذّٛل وٕتط ٘ؿجت ثٝ ظ٤جب٣٤ آظاز؛ ظ٤طا زض ٞط زٚ، ٤ه ثرف اظ قتبِٛز٠ ؾس ٔحى ثتٛزٖ حىتٓ ض ٔفْٟٛ، حىٓ شٚل٣ ٔحى ٚ ثرف ز٤ٍط غب٤بم ٖم٣ّ اؾت. ثٝ ٘ٓط ٣ٔ ثبقس. زض ظ٤جب٣٤ ٚاثؿتٝ تٛرٝ ظ٤جبقٙبذت٣ ٣ٖٛ٘ ٔفْٟٛ ٔكىه اؾت وٝ زاضا٢ زضربم ٔرتّف ٣ٔ ٖ ثٝ وٕبَ ي٥ٕٕٝ قسٜ، ذّتٛل آٖ ضا وتٓ ٔت٣ رتب٣٤ وتٝ زضن ظ٤جتب٣٤، حبنتُ وٙتس، أتب اظ آ / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ اظ ٤ه ؾٛ آَ ظ٤جب٣٤ ٥٘ع ٕٞب٣ٍٙٞ آظاز ل٠ٛ ذ٥بَ ٚ فٟٓ اؾت، اضظـ ظ٤جبقٙبذت٣ ٥٘ع زاضز. زض ا٤سٜ َ ٔتٗبضف وبٞس ٚ اظ ؾ٢ٛ ز٤ٍط ٚرٛز ا٤س٠ ا٤س٠ ٖم٣ّ ذّٛل آٖ ضا ٣ٔ َ لت٠ٛ وتٝ ٔحهتٛ ٚ ذ٥تب ضٚز، ٔت٣ ثٝ قٕبض ٔحى شٚل٣ نٛضم اؾت ٚ تزطث٣ ٞب٢ زازٜ ٔجٙب٢ ثط فٟٓ ل٠ٛ ثب آٖ آظاز ثبظ٢ زٞس. ثٝ آٖ اضظـ ظ٤جبقٙبذت٣ ٣ٔ تط اقبضٜ َٛض٢ وٝ پ٥ف ٕٞبٖٞب٢ ا٤ٗ زٚ ٔفْٟٛ ضا ثطقٕطز. تٛاٖ تفبٚم رب ٣ٔ اظ ٥ٕٞٗ وٙٙس٠ آظاز ثٛزٖ ٤ب ٚاثؿتٝ ثتٛزٖ ظ٤جتب٣٤ زض زاٚض٢ ا٥ٖتبٖ قس، چ٣ٍٍ٘ٛ ِحبِ ؾٛغ٠ ٔتأُٔ ت٥٥ٗٗ تٛا٘س اظ ِحب٣ْ ظ٤جب٣٤ ٚاثؿتٝ ثبقس ٚ ثتٝ ِحتب٣ْ ز٤ٍتط ٔٛضز تأُٔ اؾت. اظ ا٤ٗ ضٚ ٤ه ٥ٖٗ ٣ٔ ٛز ٘ساضز. اِجتٝ ٕٔىٗ اؾت ا٤ٗ أتط آَ ظ٤جب٣٤ ٚر ظ٤جب٣٤ آظاز ثٝ قٕبض آ٤س، أب چ٥ٙٗ چ٥ع٢ زض ا٤سٜ آَ تغ٥٥ط قطا٤ٍ تزطثت٣ ٚ رغطاف٥تب٣٤ زض ا٤تسٜ . ظ٤طاا٢ ز٤ٍط ثٝ ٖٙٛاٖ قجبٞت شوط وطز ضا ثٝ ٌٛ٘ٝ تٛا٘س ٔٗبزَ تغ٥٥تط ِحتبِ آَ ظ٤جب٣٤ اؾت، ٣ٔ ظ٤جب٣٤ وٝ ؾجت تغ٥٥ط ا٤س٠ ٔتٗبضف ٚ ثٝ تجٕ آٖ ا٤سٜ ٙبٖ ٤ه تفبٚم ٖٕتس٠ ز٤ٍتط ثت٥ٗ ا٤تٗ زٚ ثتبل٣ زض زاٚض٢ ظ٤جب٣٤ ٚاثؿتٝ ثبقس. ثب ا٤ٗ حبَ، ٕٞچ ٝ ٞتط ثب ٖم٣ّ غب٤بم ٚ وٕبَ ٔفْٟٛ ٚاثؿتٝ ظ٤جب٣٤ زض ٔب٘س. اظ ٔٙٓط وب٘ت، ٣ٔ ٥ٖٙت٣ ٚرتٛز ٌٛ٘ت ٖ ظ٤جتب٣٤، آَ ا٤سٜ قٛ٘س، أب تٟٙب ٔهساق ٣ٔ ٕٞطاٜ ٝ ٚ اؾتت ا٘ؿتب .وٙتس ٔت٣ ثؿتٙسٜ آٖ وب٘تت ثت ٞب٢ ٖمُ ٘ٓط٢ آَ ٔب٘ٙس ا٤سٜ ،ط٤ٗ ا٘ؿبٖآَ ظ٤جب٣٤ )ٔخُ اٖال٢ شٚق( ٕٞچٖٛ ظ٤جبت ٕٞچ٥ٙٗ ا٤سٜ ٥٘بفت٣ٙ اؾت ٚ ٔهساق ذبضر٣ ٘ساضز، أب ثطا٢ ظ٤جتب٣٤ ٚاثؿتتٝ تحمك ،ٔخُ ا٘ؿبٖ فطظا١٘ ؾمطا٣َ قٛز. قٕبض٢ ٤بفت ٣ٔ ٔهبز٤ك ث٣ بىدی کاوت وقد ي بررسی تقسیم پ٥ف اظ اقبضٜ ثٝ ٘تب٤ذ ا٤ٗ ٘ٛقتبض قب٤ؿتتٝ اؾتت وتٝ ثتٝ ثطذت٣ اظ ا٘تمتبزام ٚاضز ثتط ثٙس٢ ظ٤جب٣٤ آظاز ٚ ٔم٥س ثپطزاظ٤ٓ. مؿ٥ٓت ثٙس٢ ظ٤جب٣٤ ثٝ آظاز ٚ ٔم٥س اظ ؾ٢ٛ ثؿ٥بض٢ اظ ٔتفىطا٣٘ ٔٛضز ٘متس ٘رؿت ا٤ٙىٝ تمؿ٥ٓ ٚ ثطضؾ٣ لطاض ٌطفتٝ اؾت وٝ ثٝ َٛض و٣ّ تفىط ٔسضٖ ٚ ثٝ َٛض ذبل تفىط ٚ ظ٤جبقٙبؾ٣ وتب٘ت٣ ٔب٘ٙتسِ ٥٘چٝ اؾت وٝ ٔٗتمس اؾتت وب٘تت، ا٘س. ٤ى٣ اظ ا٤ٗ ٔتفىطاٖ ضا ٔٛضز ٘مس ٚ ثطضؾ٣ لطاض زازٜ ٚ ٞٙط زض ثبض٠ ثٍٙطز،( آفط٤ٙٙسٜ ٤ب) ٞٙطٔٙس تزطث١ ز٤سٌبٜ اظ ِٝٔؿأ ثٝ ا٤ٙىٝ رب٢ ثٝ ف٥ّؿٛفبٖ، تٕبِْ ٔفِْٟٛ[ ثبظ٢ِ] ٚاضز ضا «تٕبقبٌط» ٘بزا٘ؿتٝ، زض ٘ت٥زٝ ٚ ا٘س٤كس ٣ٔ «تٕبقبٌط» چكِٓ اظ تٟٙب ظ٤جب أط اٚ زض تٗط٤تف . ظ٤تطا ٥٘چٝ، ز٤سٌبٜ وب٘ت٣ ثٝ زٚض اظ ٚال٥ٗت تزطث٣ اؾتوٙس. اظ ٘ٓط ٣ٔ «ظ٤جب أط» ظ٤جب٣٤ احؿبؾبم ٚ ٥ٞزب٘بم ٚ ا٘فٗبالم آز٣ٔ ضا وٝ حبو٣ اظ حؽ ح٥بم ٚ ظ٘س٣ٌ اؾت زض ٔمبثُ اظ ز٤ٍط ٔٙتمساِٖ ثبٚض ثٝ ظ٤جتب٣٤ (. ٥ٌnietzsche, , - طز) ظ٤جب٣٤ آظاز ٘بز٤سٜ ٣ٔ ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ ٝ فطا٘ىفٛضم اقتبضٜ وتطز ٔىتت ٔٙتمس٤ٗ تٛاٖ ثٝ آظاز وب٘ت٣ ٣ٔ ٝ زض ٚ ارتٕتب٣ٖ وتبضوطز٢ وت ٘ت٥زت زض زازٜ ضخ زٌط٣ٌ٘ٛ ٚ ٔسضٖ ٞٙط پ٥ٛ٘س ثط تأو٥س ثب ث٥ٙب٥ٔٗ ا٘س. ٚاِتط لب٤ُ ٞٙط ثطا٢ ٔساض ُّٖمٝ ٘بٌع٤ط، ٖ ثطرؿتٝ آزٚض٘ٛ ثب تئٛزٚض ٔسضٖ؛ تزطث١ ٔب٥ٞت ٚ حؿ٣ ازضانِ ؾطقت تت تتبض٤ر٣ ٔب٥ٞتت وتطز ٞٙط٢، ظ٤جب٣٤ آظاز آحبض تبض٤دِ ٚ ربٔٗٝ ثب اـ ز٤بِىت٥ى٣ ضاث١ُ ٚ آٖ ذٛزآ٣ٙ٥٤ ٚ ٞٙط٢ احط ارتٕب٣ِٖ ا٘س٤كتب٘ٝ اؾتت وتٝ ٣ اظ ٘ٓط ا٤ٗ ٔتفىطاٖ ثؿ٥بض ؾبزٜزٞٙس. ثٝ َٛض وّ وب٘ت٣ ضا ٔٛضز ٘مس لطاض ٣ٔ ٚ ٞٙتط ظ١ٙ٥ٔ ارتٕب٣ٖ ٚ فط٣ٍٙٞ ٔس ٘ٓط لطاض زاز. فطٚوبؾتتِٗ اظ طظ٤جب٣٤ ضا ٕٞب٘ٙس وب٘ت لُٕ ٘ٓ ٔىتتت انت٣ّ زغسغت١ ٚ ِٝٔؿتأ ٕٞبٖ ٣ٙٗ٤) ان٣ّ ١ِٔؿأ ٔب ضا اظ ُّٔك، فطِْ ٤ب قىُ ظ٤جب٣٤ ثٝ adorno, , .) زاضز) ثبظ٣ٔ ٞٙط ض٣٤ِٚ چٝ اظ ٚ چطا٣٤ ٣ٙٗ٤( فطا٘ىفٛضم ٖ ثبظ ٣ٔ ا٢ٚ ان٣ّ ٞبازٖب٤ى٣ اظ ثٝثٙس٢ وب٘ت ا٘تمبز ز٤ٍط ثٝ تمؿ٥ٓ ٌٛ٘تٝ ٌطزز. ٕٞتب حىب٤تت اظ ،ثٙس٢ ظ٤جب٣٤ ثتٝ آظاز ٚ ٔم٥تس آٖ اؾت وٝ تمؿ٥ٓ ،ازٖبٞب٢ وب٘ت وٝ ث٥بٖ قس ٤ى٣ اظ ٣ٖٛ٘ تفبٚم زض ض٤ٚىطز ٤ب ٍ٘بٜ ٔب زاضز ٚ ٘ٝ تفبٚم زض ا٥ٖبٖ ذبضر٣. اٌط ثٝ ٤ته ٌتُ ضظ اظ ٍ٘تبٜ قٙبؼ ٍ٘بٜ و٥ٙٓ، زاٚض٢ ٔب ز٤ٍط ٔحى ٘رٛاٞس ثٛز ٚ ظ٤جب٣٤ حبنُ قتسٜ ٥٘تع ظ٤جتب٣٤ ٤ه ٥ٌبٜ آٖ ٌتُ نتطفبً اظ تٕب٣ٔ غب٤بم ٣ٙ٥ٖ ٚ قٙبذتٝ قس٠٘ٓط اٌط لُٕٝ آظاز. حبَ ٔم٥س ذٛاٞس ثٛز ٚ ٘ نٛضم زاٚض٢ ٔب آظاز ٚ اٌتط ثٝ فطْ ٚ نٛضم آٖ ثپطزاظ٤ٓ ٚ آٖ ضا ٔٛضز زاٚض٢ لطاض ز٥ٞٓ، زض ا٤ٗ ٓ ضغٓ ا ظ٤جب٣٤ آٖ آظاز ذٛاٞس ثٛز. ٣ّٖ ،آٖ ٌُ ضا ظ٤جب ثسا٥٘ٓ ثٙتس٢ ٤ٙىٝ ا٤تٗ ٘تٛٔ تٕتب٤ع ٚ تمؿت٥ قٛز وٝ ز٤سٌبٜ ظ٤جبقٙبذت٣ اٚ زض حُ ٚ فهُ ثؿ٥بض٢ اظ اذتالفبم شٚلت٣ ٔٛفتك ٣ٔ وب٘ت٣ ؾجت ضؾس وٝ ٔكىُ ثؿت٥بض ٥ٕٖمت٣ ضا ثتطا٢ ز٤تسٌبٜ ظ٤جبقتٙبذت٣ اٚ ا٤زتبز أب ثٝ ٘ٓط ٣ٔ ،ُٖٕ وٙس ضا ُٔتطح وتطز وتٝ آ٤تب پطؾتف تتٛاٖ ا٤تٗ ٔت٣ ،وٙس. ثب زض ٘ٓط ٌطفتٗ تٛي٥حبم ث٥بٖ قتسٜ ٣ٔ ٘ٓط اظ غب٤بم ٣ٙ٥ٖ ٚ قٙبذتٝ قتس٠ ٣ أٛض ٔٛرٛز زض ٖبِٓ َج٣ٗ٥ ضا لُٕٞب٢ تٕبٔ تٛا٥٘ٓ فطْ ٣ٕ٘ ،اٌط تفبٚم زض ٍ٘بٜ ٚ ض٤ٚىطز ثبقس ؟ثرف ث٥بث٥ٓ ٞب ضا ظ٤جب ٚ ِصم ُٔ لطاض ثس٥ٞٓ ٚ آٖٔٛضز تأ ٞب آٖ تتٛاٖ زض ٔت٣ . ظ٤تطا اؾت ٕٔىٗ ٚ ٔٗمَٛ اؾت. پؽ ثب٤س ثپص٤ط٤ٓ وٝ ٕٞٝ چ٥ع ظ٤جب ا٤ٗ أط وبٔالً نٛضم آٖ ضا ظ٤جب زا٘ؿت. ٞب ضا ٔس ٘ٓط لطاض زاز ٚ زض ا٤ٗ فطْ آٖ نطفبً ،چ٥ع٢ زض ٖبِٓ ٍ٘بٜ ثٝ ٞط ٖجج ٚ ث٥ٟتٛزٜ أط٢ ز٤ٍطاٖ،چ٣ٙ٥ٙ نحجت اظ ظ٤جبتط ثٛزٖ ثطذ٣ اظ أٛض ٘ؿجت ثٝ زض قطا٤ٍ ا٤ٗ ذت٣ ب٣ٍٙٞ آظاز لٛا٢ قٙبٕٞ ٞب ثٝ ذبَط ظ٤جب لّٕساز ٕ٘ٛزٖ آٖ ،ثٙب ثط ازٖب٢ وب٘ت . ظ٤طاذٛاٞس ثٛز ُٔ فتطْ ٕٞب٣ٍٙٞ حبنُ اظ تأوٝ وٙس ٚ اظ آ٘زب٣٤ ٞب ثطا٢ ٔب ا٤زبز ٣ٔ ُٔ زض فطْ آٖاؾت وٝ تأ س. اٌتط وب٘تت ا٤تٗ ٞب ثٝ ٤ه ا٘ساظٜ ظ٤جب ٞؿتتٙ آٖ ز اؾت ٚ ٘ٝ ٔم٥س، پؽ ١ٕٞآظا ،تٕب٣ٔ ا٤ٗ أٛض پتؽ ثب٤تس ازٖتب ت حبو٣ اظ ا٤ٗ أط اؾت «حىٓ ٠٘مس لٛ»وٝ قٛاٞس ٔٛرٛز زض ت ٘ت٥زٝ ضا ٘پص٤طز / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ ثّىٝ ثٝ ذهٛنت٥ت٣ ،ٌطزز ٣ٕ٘ تمبٚم زض ض٤ٚىطز ٚ ٍ٘بٜ ٔب ثطوٙس وٝ تفبٚم ظ٤جب٣٤ آظاز ٚ ٔم٥س ثٝ اٌتط اٚ . ظ٤تطا تٛا٘تس ثپتص٤طز وب٘ت ا٤ٗ ازٖب ضا ٥٘ع ٣ٕ٘ ،ٕ٘ب٤س. اظ ؾ٢ٛ ز٤ٍط زض ذٛز ا٥ٖبٖ اقبضٜ ٣ٔ ؾب٣٤ آٖ و٥ف٥ت ٤ب و٥ف٥تبم ثبقتس. زض ظ٤جب٣٤ ضا و٥ف٥ت ٤ب و٥ف٥بت٣ زض ا٥ٖبٖ ثسا٘س، ثب٤س لبئُ ثٝ قٙب ٞب٢ قتبذت٣ َطح قٛز ٚ ٥ٞچ ٥٘تبظ٢ ثتٝ فتطو اٚض٢زنٛضم زاٚض٢ ظ٤جبقٙبذت٣ ثب٤س ش٤ُ ا٤ٗ ٘ٛٔ رس٤س٢ اظ حىٓ ٚ ٘مس آٖ احؿبؼ ٘رٛاٞس قس. آَ ا٤تسٜ »تط اقبضٜ قتس، ايتبفٝ وتطزٖ ٔفتب٣ٕ٥ٞ ٕٞچتٖٛ َٛض٢ وٝ پ٥ف ٕٞبٖؾْٛ، ثتط قتٛز. وب٘ت زض ضاؾتب٢ زغسغت١ اذاللت٣ اٚ اضظ٤تبث٣ ٔت٣ اظ ؾ٢ٛ« ظ٤جب٣٤ ٚاثؿتٝ»ٚ « ظ٤جب٣٤ ثٙس٢ وب٘تت زض ثتبة ٘ؿتجت ٝ قسٜ اظ ؾ٢ٛ ف٥ّؿٛفبٖ تح٣ّ٥ّ، نٛضمٞب٢ اضائ ثٙس٢ اؾبؼ تمؿ٥ٓ ( لتطاض radical moralism«)ٌطا٣٤ افطاَت٣ اذالق»اضظـ ظ٤جبقٙبذت٣ ٚ اضظـ اذالل٣ ش٤ُ ٞتب٢ ز٤تسٌبٜ .(carroll, , - and gaut, , - )٥ٌتطز ٔت٣ ٖ افطا٣َ زض ثبة ٘ؿجت ٞٙط ٚ اذالق، زض ا٤ٗ أط ٔكتطوٙس -ٞتب زض زاٚض٢ اذاللت٣ وتٝ ٘ت٥زت١ آ زا٘ٙس ٣ٔ ٖبْ قَٕٛ زاضا٢ ضا اذالل٣ قٛز وٝ اضظ٤بث٣ ظ٤جبقٙبذت٣ آحبض ٞٙط٢، ٔٙزط ثٝ ا٤ٗ أط ٣ٔ ٖ ٞٙطٞتب اظ طذت٣ زٞٙس ٚ ا٤ٗ زض حب٣ِ اؾتت وتٝ ث ٣ٔ رب٢ ٔمِٛٝ ا٤ٗ زض ضا ٞٙطٞب تٕبْ ٚ ٕٞچتٛ ا٘تمتبز . زاز لطاض اذالل٣ اضظ٤بث٣ ٔٛضز ثكٛز وٝ ٘ساض٘س اذالل٣ ٚرٝ ا٘تعا٣ٖ، ٘مبق٣ ٤ب ٘بة ٔٛؾ٥م٣ اؾتبؼ ثتط بٔالًتوت ( ٔهبز٤ك ٚ ٞب ٌٛ٘ٝ تٕبْ قبُٔ) ط٢تٞٙ طتاح ٞط اضظـ اٌط وٝ اؾت ا٤ٗ ز٤ٍط ا٢ ط٢تاحط ٞٙت وٝ و٥ٙٓ ٣ٔ تهس٤ك ٛالًتٕٔٗ ٔب ٛ٘ٝتچٍ پؽ ٛز،تق ٣ٔ ت٥٥ٗٗ آٖ الل٣تاذ ؾطقت ٥ٙٗ تٕٞچت ثبقتس؟ آفط٤ٗ ِٝٔؿأ اؾت ىٗتٕٔ آٖ ٣تاذالل تتٕٙس اؾت ٚ زض ٥ٖٗ حبَ ؾطقتاضظق ٥ف تٗ َت تٓط ٌطفتت تاؾتت، ثتب زض ٘ت طتذ٥ت اظ بز٢تٕ٘ت ذتٛز ٣ چ٥ٙٗ حى٣ٕ وٝ ظ٤جبتزٞٓ تت٥ٕٗ «سْٚتؾ نس ٚ ث٥ؿت ضٚظِ»تٛاٖ ضٔبٖ ٛ٘ٝ ٣ٔتبز٤ك ثب اقىبَ ٣ٕٟٔ ضٚثطٚ اؾت. اظ رّٕٝ چٍتٔه ( days of sodom(احط ؾبز )marquis de sadeضا ٥٘ع ٕ٘بز ذ٥ط اذالل٣ ثسا٥٘ٓ؟ ) وتیجٍ ٝ »ٚ «آَ ظ٤جب٣٤ ا٤سٜ»زض زٚ ٔفْٟٛ ت ، زاٚض٢ ظ٤جبقتٙبذت٣ ثتط ٔجٙتب٢ «ظ٤جب٣٤ ٚاثؿتت ٚ اظ آٖ رٟتت وتٝ لت٠ٛ فٟتٓ زض زاٚض٢ )ثتطذالف ظ٤جتب٣٤ آظاز( ٔٙس٢ ٣ٙ٥ٖ زض٣٘ٚ اؾتت غب٤ت قٛز، ٞتط زٚ ا٤ٗ زٚ ٔفْٟٛ ٘مف زاضز ٚ غب٤بم ٣ٙ٥ٖ ث٥ط٣٘ٚ زض ا٤ٗ زاٚض٢ زاذُ ٣ٕ٘ ظ٤جبقٙبذت٣ ٘ؿجت ثتٝ ظ٤جتب٣٤ آظاز ذّتٛل ،ٞب٢ ٖم٣ّ اضظـ ظ٤جبقٙبذت٣ زاض٘س. اِجتٝ ثٝ ٚاؾ١ُ تطو٥ت ثب ا٤سٜ وٕتط٢ زاض٘س. ٔٙس٢ اظ رٟت ٘ٛٔ غب٤ت ،زض ٔمب٤ؿٝ ثب ٤ىس٤ٍط «ظ٤جب٣٤ ٚاثؿتٝ»ٚ «آَ ظ٤جب٣٤ ا٤سٜ» ت ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ تط٢ ٘ؿجت ثٝ ظ٤جتب٣٤ آظاز لتطاض ٚ ذّٛل ظ٤جبقٙبذت٣ ثب ٤ىس٤ٍط اقتطان زاض٘س ٚ زض رب٤ٍبٜ پب٥٤ٗ ٞب٢ ٖم٣ّ، چ٣ٍٍ٘ٛ ِحبِ فطو ٌطفتٗ ا٤سٜ ا٤ٗ زٚ ٔفْٟٛ زض ٘ٛٔ پ٥ف ،٥ٌط٘س. اظ ؾ٢ٛ ز٤ٍط ٣ٔ ٞب ثب ٤ىس٤ٍط تفبٚم زاض٘س. قسٖ زض زاٚض٢ ظ٤جبقٙبذت٣ ٚ ٔهساق ثتب يتٛاثٍ حىتٓ «ظ٤جب٣٤ ٚاثؿتٝ»ٚ «آَ ظ٤جب٣٤ ا٤سٜ»ذت٣ وٝ رب٤ٍبٜ ظ٤جبقٙب ثب آٖ ت شٚل٣ ٔحى وب٘ت ٔج٣ٙ ثط ٤بفتٗ انَٛ زاٚض٢ پ٥ك٣ٙ٥ ٚ ٍٕٞب٣٘ ظ٤جبقٙبذت٣، ٍٕٖٞٛ ٥٘ؿتت، تٛاٖ ا٤ٗ ٔفب٥ٞٓ ضا زض ضاؾتب٢ زغسغ١ اذالل٣ اٚ زض لبِت لّٕساز وطزٖ ظ٤جتب٣٤ ثتٝ ٖٙتٛاٖ أب ٣ٔ آَ ظ٤جتب٣٤ ضا زض ٞب٢ ٖم٣ّ زض ا٤سٜ اض زاز ٚ ٕٞطا٣ٞ ا٤س٤ٜٚػ٣ٌ ٤ب نفت٣ ٔتّٗك ثٝ تطاظ٢ ٚاال، لط ٞب٢ فٛق ٔحؿٛؼ ٔالحٓٝ وطز. رٟت ٔحؿٛؼ ؾبذتٗ ا٤سٜ ت تٛرٝ ثٝ رب٤ٍبٜ تفى٥ته ظ٤جتب٣٤ آظاز ٚ ٚاثؿتتٝ ٚ ٕٞچٙت٥ٗ ٚاضز وتطزٖ ٔفتب٣ٕ٥ٞ ثتٝ ٔٙس ٚ ربٕٔ وب٘ت زض ظ٤جبقٙبؾ٣ اؾت وٝ تزط ٌط ز٤سٌبٜ ٘ٓبْ ، ٘كبٖ«آَ ظ٤جب٣٤ ا٤سٜ»ٕٞچٖٛ قٙبؾ٣، ٔبثٗساُِج٥ٗتٝ ٚ ٞب٢ َج٣ٗ٥ ٚ ٞٙط٢ ضا ثٝ ٔفب٥ٞٓ اؾبؾ٣ ٔٗطفت ظ٤جب٣٤ زضثبض٠ٚ احىبْ ٔب ٞب٣٤ ؾجت آٖ قسٜ اؾت وٝ ٥ٔطاث اٚ تٛؾٍ افتطاز٢ ٕٞچتٖٛ زٞس. چ٥ٙٗ ٤ٚػ٣ٌ اذالق ضثٍ ٣ٔ ق٥ّط، ٍُٞ، قٛپٟٙبٚض، ٥٘چٝ ٚ ثؿ٥بض٢ اظ ٤ٛ٘ؿٙسٌبٖ لطٖ ث٥ؿتٓ ٘مس ٚ ز٘جبَ قٛز. َا وًشت پی ال٢تاٖ ٔخُ ثب٤س وؿ٣ ٞط ٤ٌٛس ٣ٔ وب٘ت وٝ ا٤ٗ . ظ٤طاتتاؾ ضٚثطٚ اثٟبْ ٤ه ثب وب٘ت ز٤سٌبٜ رب ا٤ٗ زض . وٕته ثٝ وٝ ذٛز ثطا٢ ا٣٤ٍِٛ ذّك. اِف: طزتپص٤ ٣ٔ ٔتفبٚم ؿ٥طتتف زٚ وٙس، ا٤زبز ذٛزـ زض ضا شٚق ١ٗتتٛؾ ٚ ٍتثؿ. ة. زاز لطاض زاٚض٢ ٚ بث٣تاضظ٤ ٔٛضز ستآ٤ٙ ٣ٔ پ٥ف طثٝتتز زض وٝ ضا ٔٛاضز٢ ثتٛاٖ آٖ ٖ ثطا٢ وٝ ذٛز ثطا٢ ٣٤ٛتاٍِ ٓ ز٤ٍتطا ٝ ٞت ٗ وت ثبقتٙس تطنتٔكت وٙٙتس، ٔت٣ بزضتنت ب٣ٔتاحىت چٙت٥ (savile, , .)ٗزض اؾت ٕٔى ٗ ٖ رتب ا٤ت ٝ قتٛز ث٥تب ٗ وت َ ا٤ت . ظ٤تطا ٥٘ؿتت ٚاضز اقتىب ٗ آَ، ا٤تسٜ ٥ٗٔبض وٕه ثٝ ظقت٣ ٤ب ظ٤جب٣٤ ؾٙز٥سٖ وٙس، ٣ٔ ث٥بٖ رب٣٤ زض وب٘ت ذٛز وٝ َٛض ٕٞبٖ ا٤ت ٓ ٥ٌتط٢ ا٘تساظٜ ٚ ثؿٙز٥ٓ ضا ٘بلم أط ب٢ٞ ٘مم ٚ ٔمساض تب وٝ زٞس ٣ٔ ضا أىبٖ ٝ آٖ ثتب . ظ٤تطا وٙت٥ وت ٓ ٣ٕ٘ ق٤ٛٓ، لب٤ُ ٣ٙ٥ٖ ٚرٛز ٞب آَ ا٤سٜ ا٤ٗ ثطا٢ تٛا٥٘ٓ ٣ٕ٘ ٝ ضا ٞتب آٖ تتٛا٥٘ ٗ ثت ٝ ز٥ِتُ، ا٤ت ٚ ؾتبذت وٝ وٙٙس ٣ٔ ت٥٥ٗٗ زاٚض٢ ٥ٗٔبض ٚ ٔالن ٖمُ ثطا٢ ٞب آَ ا٤سٜ ا٤ٗ چطاوٝ آٚض٤ٓ؛ حؿبة ثٝ ٞٗش پطزاذت١ أتط زض ٔٛرتٛز ٞتب٢ ٘متم و٥ف٥ت ٚ و٥ٕت تب زٞٙس ٣ٔ ضا أىبٖ ا٤ٗ آٖ ثٝ ٚ ثرك٥سٜ ٔفْٟٛ ٖمُ ثٝ ٞتب آَ ا٤تسٜ ا٤ٗ وٝ زٞس ٣ٔ ٘كبٖ أط ا٤ٗ(. kant, , a )وٙس اضظ٤بث٣ ٚ ثؿٙزس ضا ٘بلم ٗ ٚ زاض٘تس زاٚض٢ ٔتٛضز ق٣ء ثب ٖمُ اضتجبٌ زض ٣ٕٟٔ ٘مف ٚ ثٛزٜ تبْ ذٛز اظ ضا ٞتب آَ ا٤تسٜ أتط ٕٞت٥ ٗ ٥٘تع تٛي٥ح ا٤ٗ ثب اِجتٝ،. ؾبظز ٣ٔ زٚض ش٣ٙٞ ٞب٢ ؾبذتٝ ٗ اؾتت ٕٔىت ٝ قتٛز ٚاضز ا٤تطاز٢ چٙت٥ وت ٝ «ة» ق٣ء اظ «اِف» ق٣ء وٝ ا٤ٗ ثٝ لَٛ نٛضم ا٤ٗ زض ثبقس، ٥٘بفت٣ٙ زؾت ٚالٗبً آَ ا٤سٜ چٝ چٙبٖ ثت ٟ٘ب٤تت ث٣ ثٝ «زٚ» ٖسز اظ «ز٤ٚؿت» ٖسز ث٥٤ٍٛٓ وٝ اؾت ٘ؿٙز٥سٜ لسض ٕٞبٖ ت،اؾ تط ٘عز٤ه آَ ا٤سٜ / آَ ظ٤جب٣٤ ٚ ظ٤جب٣٤ ٚاثؿتٝ زض فّؿفٝ وب٘ت ٘ؿجت ا٤سٜ ٗ زض وب٘ت ٚ اؾت تط ٘عز٤ه ٚ( savile, , , footnote )٘تساضز حّت٣ ضاٜ ٔتٛضز ا٤ت .٥٘ؿت ٥ٗٔبض ٘جٛز ثطا٢ ٌكب٣٤ ضاٜ احط اضظ٤بث٣ ثطا٢ آَ ا٤سٜ ٤ه ت٥٥ٗٗ .( ) ز٤ٍطاٖ، ٚ ٚاِتط ثطا٢ اَالٖبم ث٥كتط، ٖ.ن: ث٥ٙب٥ٔٗ، . ىابعم ثتتبة زض ٞتتب٣٤ ٘ٛقتتتٝ ٌع٤تتسٜ: ا٘تمتتبز٢ ظ٤جبقٙبؾتت٣ ،( ) .ز٤ٍتتطاٖ ٚ ٚاِتتتط ث٥ٙتتب٥ٔٗ، - .٘ٛ ٌبْ،تٟطاٖ ٟٔطٌبٖ، ا٥ٔس تطر١ٕ ٚ ٌع٤ٙف ،قٙبؾ٣ ظ٤جب٣٤ .٣٘: تٟطاٖ، ٖجساِىط٤ٓ ضق٥س٤بٖ تطر١ٕ، ٘مس ل٠ٛ حىٓ(، ، )ا٤ٕب٘ٛئُ وب٘ت، - - adorno, theodor. ( ), aesthetic theory: theory and history of literature, trans. and ed. robert hullot-kentor, minnesota: university of minnesota press. - allison, henry e. ( ), kant’s theory of taste: a reading of the critique of aesthetic judgment, london: cambridge university press. - bowie, andrew. ( ), aesthetics and subjectivity: from kant to nietzsche, second edition, manchester: manchester university press. - carroll, noël. ( ), "morality and aesthetics", encyclopedia of aesthetics, michael kelly (ed.), new york: oxford university press, vol. , pp. - . - coleman, francis x. j. ( ), the harmony of reason: a study of kant’s aesthetics, pittsburgh: university of pittsburgh press. - crawford, donald w. ( ), “kant” in the routledge companion to aesthetics, london: routledge, pp. - . - deleuze, gilles. ( ), kant’s critical philosophy: the doctrine of the faculties, trans. hugh tomlinson and barbara habberjam, london: the athlone press. - gaut, berys. ( ), art, emotion and ethics, oxford: oxford university press. - guyer, paul. ( ), kant and the claims of taste, second edition, london: cambridge university press. - kant, immanuel. ( ), critique of pure reason, trans. norman kemp smith, london: macmillan. - kant, immanuel. ( ), groundwork of the metaphysics of moral, trans. & ed. mary gregor, london: cambridge university press. - körner, stephan. ( ), kant, london: penguin books. - nietzsche, friedrich. ( ), on the genealogy of morality, ، قٕبضٜ ، ثٟبض ٚ تبثؿتبٖ ؾبَ ،اهی فلسفیژپوهش/ trans. walter kaufmann, new york: vintage books. - savile, anthony. ( ), “kant and the ideal of beauty” in art and morality, london: routledge, pp. - . - scarre, geoffrey. ( ), “kant on free and dependent beauty” in immanuel kant critical assessments, vol. iv, london and new york: routledge, pp. - . - scruton, roger. ( ), kant: a very short introduction, new york: oxford university press. - zimmerman, robert l. ( ), “kant: the aesthetic judgement” in immanuel kant critical assessments, vol. iv, london and new york: routledge, pp. - . prospects for beauty physics at hadron colliders k. t. mcdonald joseph henry laboratories princeton university princeton, new jersey introduction n a t u r e wants us to do b physics! t h e b lifetime is - . psec - can observe the decay vertex separated from the production vertex. t h e b's can be isolated even when produced in hadronic interactions. b o - eo mixing is large - phenomenology rich in quantum-mechanical effects. t h e cross-sections for g g - b b a r e large a t collider energies.'t r h i c tev i ssc . / / / @ t h e signal to noise for beauty a t the s s c is comparable to that for charm in b-decay products a r e soft: % of all tracks have p, < gev/c. * c a n follow a classic prescription for detailed study of particles: measure the cp violation is accessible. fixed-target photoproduction. decays to few-body, all-charged final states. - a -u signal for a cp-violating asymmetry of . requires reconstructed events. - need ' reconstructible pairs if branching fraction = lo-'. - need o'o pairs produced if reconstruction efficiency = %. - t h e luminosity needed to produce such a sample in lo sec is then l = lo * cm- sec-' a t r h i c l = . x lo ' cm- sec-' a t tev i l = x cm-'sec-l a t s s c - how to survive in high multiplicity. t h e crispness of the cp-violation physics encourages us to tackle difficult issues. tracks/event; samplesltrack - - lo wordslevent. can readily find patterns if detector occupancy is - need - l o detector elements (- /layer). - how to survive a t high rate. annals new york academy of sciences have - m h z event rate a t l = need sparse readout and buffering of the lo elements struck per event. - - gword/sec raw event rate! front-end analog triggers reduce event rate to < l o khz. numeric-processor farm reduces rate to - khz. archival data rate - mbytelsec to video tapes. cm- sec-'. * t h e same detector concept applies to rhic, tev i, and the ssc. figure shows the beauty spectrometer as conceived a t the snowmass workshop. prejudices about cp violation in the b-b system the best signal for cp violation is an asymmetry: r(b--f) - l?(b-f) i'(b--f) + l?(b-f) ' a = the theoretical interpretation of a is clean only w h e n f = f = cp eigenstate. - must tag the other b of the b - i p a i r . - 'self-tagging' modes like b o - k - r - or d + t - might be more accessible experimentally, but a r e less useful theoretically. (like e ' / e in ko - tt these depend on penguin diagrams. . .) large a - small r, in most models. to reach s standard deviations in a measurement of a for mode b - f with branch i', need n produced b s , where example: s = , a = . , r = - n = x '. -. ssc beauty spectrometer (snowmass ' ) figure . a beauty spectrometer concept. mcdonald prospects for beauty physics p i - " t s figure . the unitarity triangle. cp violation and the km matrix (wolfenstein): vud vus vub wi.x (p - ilt) v k m = [ ; ; ; ;i=[ - a fa . p ~ ( - - ilt) -& x - the cabibbo angle. p is known via the b lifetime. # - cpviolation. but, p , a r e not well determined from the kesystem. bjorken's trick: unitarity of v k m - v r d + xvrs + v,*, = . - t h e b-bsystem is the place! - these vectors form a closed triangle. on dividing the lengths by px , we obtain figure . since the base is known, the experimental challenge is equivalent to measuring the interior angles ,, &, &. for b --fwithfa cp eigenstate, the asymmetry a depends only on sin @ a - sin , for b - + k ~ , ddk,, +?t?t, do, d o ? t + t - , . . . a - sin $* for b - ?t+?t-, p p , . . . a -sin($, - ,) for b - e*' k s , . . . an overconstrained study of cp violation in the km matrix requires the observation of many decay modes. =) need a general purpose detector with particle identification. - need tagging of the second b. - an extensive program for the 's! pre-cp physics in the b-b system o b ~ - gluon structure functions a t collider energies. bh&and b,-& mixing. t h e latter is large but surprisingly hard to measure owing to rapid oscillations. annals new york academy of sciences r ( b --f) for likely cp-violating modes - a rich program even before cp violation. recent detector proposals . march , letter of intent to f n a l by volk, reay et ul . march , letter of intent to f n a l by van berg, lockyer et al. . july , ssc beauty spectrometer a t the berkeley workshop.s . november , dipole beauty spectrometer a t the f n a l beauty work- . june , status report of the fermilab b collider study group.' . july , ssc beauty spectrometer at the snowmass workshop.* shop! e l e v a t i o n v i e w figure . overview of the bcd detector. . july , solenoid beauty spectrometer a t the r h i c workshop.' . august , letter of intent to c e r n by brandt, schlein et a[." . october , letter of intent for a bottom collider detector for the fermilab tevatron." overview of the bottom collider detector we will use the recently proposed bottom collider detector" as an example. a schematic side view is shown in figure . the design is driven by the need for large angular acceptance, good momentum resolution for low-momentum tracks, precision vertexing, and particle identification. calorimetry is not important except for electron mcdonald. prospects for beauty physics identification. the basic character of the detector is ‘central,’ but with greater emphasis on the angular region o < < ° than in present detectors designed for w and z physics. a a dipole magnet is chosen to optimize the detection of tracks produced between o < < o (pseudorapidity: - < < ). the kinematics of b - b production a r e such that both forward and central tracks must be measured well to have a high geometric acceptance, while transverse momenta greater than gev/c are seldom of interest. a dipole magnetic field oriented perpendicular to the beams is the best and simplest solution. a low-field ( tesla), large-diameter magnet is preferable for pattern recognition of low-momentum tracks. t h e magnet design calls for circular pole tips of -m diameter, separated by a -m gap. this large gap permits a tracking system with - samples per track, the minimum acceptable number in a high-multiplicity event, while still accommodating the em calorimeter, trd, and r i c h counters inside the gap. t h e vertex detector is designed to find the secondary vertices of b particles with high accuracy and efficiency, thereby isolating the b from the rest of the event. t h e resulting ability to study the time evolution of the states is particularly advantageous for cp studies. extensive monte carlo simulation indicate that -d vertex reconstruc- tion is necessary to achieve good pattern recognition, and that the system should have a worst-case impact-parameter resolution of < pm. all tracks should intersect a t least planes with an angle of incidence t s . these requirements, along with the length of the interaction region, led to a hybrid design of barrels and planes of double-sided silicon detectors. these devices are located outside the beam pipe, beginning a t . -cm radius, to minimize the effects of multiple scattering. monte carlo studies of this design, where tracking efficiencies were loo%, gave an efficiency of finding b vertices of - %. a preliminary mechanical model of this detector design has been constructed. * t h e vertex detector relies on the gas tracking system for most of the pattern recognition. the tracking system is designed for efficient and rapid -d pattern recognition of tracks over the full angular range. there are - samples along each track. the technology used is thin-walled straw tubes, pressurized to atmospheres and arranged in superlayers. such straw tubes permit a measurement error of pm per hit. this high precision will allow a mass resolution of mev/c and an extrapolation error into the silicon vertex detector of pm. good mass resolution is desirable to separate bd from b,, and to set a narrow mass window around the b as a rejection against combinatoric background. particle identification is important in reducing the combinatoric background, especially for modes such as b - kt and b - p p . electron identification is required for triggering and tagging the particle-antiparticle nature of the b . the design incorporates trd’s r i c h counters, and an electromagnetic calorimeter over the full detector acceptance and for the full momentum range of the b-decay products. t h e trigger and data-acquisition system is designed to handle a luminosity of lo ’ cm- sec-’ and data-flow rates of gigabytes per second. the trigger philosophy is to assemble the full event as soon as possible and pass it to a farm of numeric processors where a variety of trigger algorithms can be implemented in software. t h e system is based on the latest communications-industry technology, which represents a new approach for high-energy physics experiments and is suitable for ssc data rates. annals new york academy of sciences - - - t - i i an initial cost estimate for the detector is $ m. i n the space remaining we elaborate slightly on two issues, a possible ‘topology trigger,’ and the data-acquisition system based around a ‘barrel switch.’ topology trigger a first-level trigger is desired that might be straightforward to implement while reducing the event rate by - . t h e ‘topology trigger’ simply counts the number of x a c i $ z i ’ a m d track tracks x i m track tracks background m n t s from u.ub.d.db.s.sb.c.cb twojet fnte%t$g’c’ figure . (upper) t h e number of charged tracks above a given p, for events containing a b - t+k- decay, according to an isajet simulation; (lower) t h e same for events without a n y b’s. mcdonald prospects for beauty physics charged tracks in the event above a given cut in p p this is illustrated in figure , based on an isajet simulation. if a cut on only a single track could be made reliably, we see that a cut a t pt = . gev/c would yield a factor of reduction in the event rate a t the expense of only a % loss of events with a -body decay such as b - a+a-. or, if two tracks a r e each required to be above gev/c, the desired reduction of the total event rate could be achieved with % loss of -body b decays. the efficiency for many-particle b decay is, of course. less. data acquisition the architecture of the data-acquisition system takes advantage of several new digital transmission over fiber-optic cables. a simple ‘barrel shifter’ switch for event building a t khz. a farm of - numeric processors, especially suited to tracking problems, approaches: in particular: which implement the second-level triggers, employing full reconstruction algorithms for some detector systems. a block diagram of the proposed data-acquisition system is shown in figure . the data flow is from top to bottom. prompt triggers (such as the topology trigger) will first reduce the data rate by a factor of - , using a subset of the detector elements labeled a-z in figure . from this point on there is no other specially built logic for triggering. if the event is accepted by the first-level trigger, the data fragments are transmitted over fiber-optic cable to the event-builder switch. there can be any number of data sources from each detector system. the event-builder switch is based on the high-speed technology of a telephone exchange. the ‘barrel-switch’ technique can accept parallel inputs from a large number of sources and reorganize these into a set of output streams, each stream containing only information from a single event. data rates of tens to a few hundreds of gigabytes/sec are possible. the receiver/formatters format the data into structures suitable for high-level language programs, and then pass the events into one member of the large farm of numeric processors. each of these processors will be the equivalent of about vax ’s and will implement the second-level trigger in software. they should reduce the event rate by another factor of , leaving a rate of - khz a t a luminosity of cm- sec-l, which can be archived to tape on video cassettes. summary the cross-section for gg - b b is relatively high a t collider energies, so that a one-year r u n a t rhic or tev i might yield > l o l a b-bpairs, and pairs a t the ssc. the challenge to the experimenter is to trigger on and reconstruct a significant fraction of this sample. detectors are being proposed that make extensive use of silicon vertexing, vlsi readout, and massive online numerical processing with the goal of annals new york academy of sciences event fragmsflts event fragments from m sources from n sources from deleclor element a from detector element z transmitted via transmitted via fiber optic cables fiber optic cables event builder (switch) 'barrel shiner with very linle memoiy i i unformatted event x+i fiber optic cables c- transmnedwa unformatted event x transmined via fiber optic cables recelverl receiver formatier formatter formaned events copper cables procassor(s) processor(s) - processor(s) t""l processor(s) p figure . block diagram of the proposed data-acquisition system. maintaining a % efficiency for few-body decays to all-charged final states. if achieved at the ssc for l = lo ' cm-'sec-', this would be equivalent to an e + e - - b factory operating at l = cm-'sec-' and % reconstruction efficiency. even at rhic or tev i with lo reconstructible b ' s , the strongest signals for cp violation in the b - b system would be accessible. references . . berger, e. l. anl-hep-pr- - . nason, p., s. dawson & r . k . ellis, fermiiab-pub- / -t. mcdonald prospects for beauty physics . . . . . . . . i . volk, j. t., n. w. reay, et al. letter of intent for a tevatron collider beauty factory v a n berg, r., n. s. lockyer, et a/. proposal for a bottom collider detector (march foley, k . j., et al. a beauty spectrometer for the ssc. in proceedings of the ssc reay, n . w., et al. in proceedings of the workshop on high sensitivity beauty physics a t status report of the fermilab b collider study group. princeton university preprint in proceedings of the snowmass workshop on physics in the ’s (july ). i n lockyer, n. s., et al. in proceedings of the r h l c workshop (july ). i n press. brandt, a,, p. schlein, et al. letter of intent to the spcs for a study of beauty and charm castro, h., et al. letter of intent for the bcd, a bottom collider detector for the fermilab (march ). ). workshop (berkeley, july ) p. . fermilab (november ). doe/er/ - (june ). press. physics at the sps collider (august ). tevatron (october ). beauty opening beauty at high { precision sensitivity chris quigg fermilab beauty · ljubljana · september , see also “dream machines” . “perspectives and questions” zenodo. mailto:quigg@fnal.gov http://www.beauty .org/en/ https://arxiv.org/pdf/ . .pdf https://doi.org/ . /zenodo. origin story . . . -gev pn → µ+µ− + x volume ) , number physical review letters november - table ii. sensitivity of resonance parameters to continuum slope. continuum subtraction of eq. ( ) but with b varied by + (t. errors are statistical only. o c . ~ o.o t bi blab l mass (gev} y m( (gev) bdo/dy(„-& (pb} ~, (gev) b do/dy i -g (pb) ~ (gev) b do/dy / ~ -o (pb) per degree of freedom . + . . + . . ~ . . + . . + . . + . . / . + . . + . . ~ . . + . . + . . + . . / b = . gev = . gev fig. . excess of the data over the continuum fit of eq. ( ). errors shown are statistical only. the solid curve is the three-peak fit; the dashed curve is the two-peak fit. table i. resonance fit parameters. continuum subtraction is given by eq. ( ). errors are statistical only. peak peak y m, (gev) bda/dye o (pb) y m, (gev) bdo./dye~ (pb) m (gev) b do/dyj, , (pb) y per degree of freedom . + . . + . . + . . + . . / . + . . + . . + . . + . . + . . + . . / cise form of the continuum. the first test is to vary the slope parameter, b, in eq. ( ). varia- tion each way by yields the results given in table ii. a detailed study has been made of the error matrix representing correlated uncertain- ties in the multiparameter fit. the correlations increase the uncertainties of tables i and ii by & %. further uncertainties in the results presented above arise from the fact that the continnum fit is dominated by the data below gev. nature could provide reasonable departures from eq. ( ) above this mass. these issues must wait for a large increase in the number of events, especial- ly above - gev. however, the primary conclu- sions are independent of these uncertainties and may be summarized as follows: (i) the structure contains at least two narrow peaks: y( . ) and y'( . ). (ii) the cross section for y( . ), (bda/ dy) i, „is' . + . pb/nucleon. (the error in- cludes our + /o absolute normalization uncertain- ty and. also the estimated uncertainty due to mod- el dependence of the acceptance calculation. ) (iii) there is evidence for a third peak y "( . ) although this is by no means established. examination of the pr and decay-angle distribu- tions of these peaks fails to show any gross dif- ference from adjoining continuum mass bins. an interesting quantity is the ratio of (bda/ dy)l, , for y( . ) to the continuum cross section (d'o/dmdy)i, , at m = . gev: this is . ~ . gev. table iii presents mass splittings and cross sections (including systematic errors) under the two- and three-peak hypotheses and compares them with theoretical predictions to be discussed below. there is a growing literature which relates the y to the bound state of a new quark (q) and its an antiquark (q).' " eichten and gottfried' have cal- culated the energy spacing to be expected from the potential model used in their accounting for the energy levels in charmonium. their potential v(r) = —~ m, (m, )/r +r/a' ( ) predicts line spacings and leptonic widths. the level spacings t table iii(a)] suggest that the shape of the potential may be oversimplified; we note that m(y') -m(y) is remarkably close to m (g') -m( )" table iii(b) summarizes estimates of bda/dyl, -, for qq states and ratios of then= , states to the ground state. cascade models (y produced as the radiative decay of a heavier p state formed by gluon amalgamation) and direct production processes seem to prefer q = —& to q =-', . we note finally that the ratios in table iii may re- quire modification due to the discrepancy between the observed spacing and the universally used e m(Υ′) −m(Υ) m(υ′′) −m(Υ′) two-level fit ± mev three-level fit ± mev ± mev m(ψ′) −m(j/ψ) ≈ mev general motivation: j/ψ, τ discoveries kobayashi–maskawa cpv insight chris quigg beauty opening ljubljana · . . / http://cds.cern.ch/record/ /files/vol -issue - -p -e.pdf?version= https://doi.org/ . /physrevlett. . https://doi.org/ . /ptp. . eichten & gottfried: cesr proposal (november ) volume b, number physics letters january h e a v y q u a r k s i n e ÷ e - annihilation* e. eichten and k. g o t t f r i e d laboratory o f nuclear studies, cornell university, ithaca, new york, , usa received november there are many speculations that there exist quarks q considerably heavier than the charmed quark. their qq states will display a far richer spectrum of monochromatic photon and hadron transitions than charmonium. the most important features of this spectrum - in particular, its dependence on the mass of q - are outlined. the l i t e r a t u r e bristles [ ] w i t h c o n j e c t u r e d quarks c o n s i d e r a b l y heavier t h a n the c h a r m e d quark. we d o n o t w a n t to pass j u d g e m e n t on the p l a u s i b i l i t y o f these speculations here. our principal p u r p o s e is t o p o i n t out a quite obvious fact: i f such super-heavy quarks q ac- tually exist and have masses mq b e l o w g e v , the new g e n e r a t i o n o f e+e - storage rings will find a spec- trum o f q(~ b o u n d states and resonances t h a t is far richer than the c c s p e c t r u m in the - gev region. this is so because for mq ~> . gev we e x p e c t three b o u n d states b e l o w the t h r e s h o l d for the zweig- allowed decays o f qq. as a c o n s e q u e n c e , the qq s p e c t r u m will d i s p l a y a very i n t r i c a t e and c o m p l e x array o f p h o t o n and h a d r o n transitions. in a d d i t i o n , the region above the zweig-decay t h r e s h o l d will con- tain a rich a s s o r t m e n t o f r a t h e r n a r r o w resonances. planning for e x p e r i m e n t s at cesr, pep and p e t r a might b e a r this e n t i c i n g p o s s i b i l i t y in m i n d . t h a t an increase o f q u a r k mass leads to s t r o n g e r b i n d i n g o f q(~ states is obvious w i t h o u t any t h e o r y . thus sg j u s t fails to have a b o u n d - s t a t e , whereas cg has two. hence we e x p e c t f u r t h e r qq - states can be b o u n d b y a s u f f i c i e n t l y large increase o f m q , and it o n l y remains to q u a n t i f y " s u f f i c i e n t l y " . the success o f the c h a r m o n i u m m o d e l [ - ] allows one to c o m p u t e the m q - d e p e n d e n c e o f the qq s p e c t r u m with a c o n s i d e r a b l e degree o f c o n f i d e n c e , and t h e r e b y to e s t i m a t e the value o f m q where a t h i r d s s t a t e is b o u n d . as in c h a r m o n i u m , we [ ] use a static qq interac- tion v(r) = ! + r s r a . ( ) * supported in part by the national science foundation. i [~((idick~ :(:i;l ' . :.::;~":':'~:~::";::::'::;;'~";#'~-;;~~:' w _ g , ~ _ ~ o o m~ i i i i ffi o (gev) fig. . qq excitation energies as a function of quark mass. the energies shown are found from the schr dinger equation with ( ) as potential. all relativistic corrections to the excita- tion spectrum are ignored. the onset of the q~+ qq conti- nuum is also shown. its position relative to the qq spectrum does depend on various corrections; see the discussion related to eqs. ( ) and ( ). the length a is assumed to be a universal c o n s t a n t cha- racterizing the q u a r k c o n f i n e m e n t i n t e r a c t i o n . the c o u l o m b i c i n t e r a c t i o n has a s t r e n g t h % ( m ~ ) whose mq d e p e n d e n c e is given b y the w e l l - k n o w n renormali- z a t i o n g r o u p f o r m u l a from c o l o r gauge t h e o r y . f r o m our analysis [ o f the c~ system, we have a = . gev - and a s ( m ) = . . the qq e x c i t a t i o n s p e c t r u m p r e d i c t e d b y v ( r ) is shown in fig. as a f u n c t i o n o f mq. ( f i n e s t r u c t u r e effects - n o t y e t u n d e r s t o o d in c h a r m o n i u m - are e ( s) − e ( s) ≈ mev general: # of narrow s levels ∝ √ mq chris quigg beauty opening ljubljana · . . / https://doi.org/ . / - ( ) - why choose mq = gev? excess events at high inelasticity observed in ν̄µn → µ+ + anything v −a: dσ(νq)/dy ∝ dσ(ν̄q)/dy ∝ ( −y) “high-y anomaly” could be explained by( u b ) r with mb ≈ – gev also at budapest . . . cdhs experiment ruled out the high-y anomaly chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevlett. . Υ( s), Υ( s) leptonic widths ; qb = − (doris, ) chris quigg beauty opening ljubljana · . . / cesr resolves three narrow Υ states ( – ) volume , number physical review letters apr&l — io- — l — c io a) - ca coe o i ~ i . i i i i & i . . . - i ~ ~ i ~ i i i i . . io.o i i , io. - -- 'i, it ii i i i i i i i i i i . i . i . i . . w = center of mass energy, gev fig. . measured cross sections, including cor- rections for backgrounds and for acceptance, but not for radiative effects. errors shown are statistical only. there is an additional systematic normalization error of + /o arising from uncertainties in efficiencies and in the luminosity calibration. the energy scale has a calibration accuracy of mev. the curves show the best fit described in the text. orbit. although cesr energy settings were found by repeated resonance scans to be reproducible to better than . /o accuracy, there is at present an uncertainty in the overall calibration scale factor amounting to about . %. the resonances near . and . gev match the & and y' observed first by herb et a~.~ and confirmed at the dorl e+e ring. ' because of the superior energy resolution of the cesr machine, our resonance peaks appear about two times higher and narrower than those observed at doris. the resonance near . gev is the first confirmation of the &" claimed by ueno et al.' we fit the data by three very narrow resonan- ces, each with a radiative tail convoluted with a gaussian energy spread, added to a continuum. ' a single fit to the three peaks with a common energy spread proportional to ~' and a common continuum proportional to ~ ' has a x equal to . per degree of freedom. the rms energy spread is . ~ . mev at ~= gev, as ex- pected from synchrotron radiation and beam- orbit dynamics in cesr. individual fits to the three peaks with independent continuum levels and peak widths give results for the rms energy spread and for "„which remain within the er- rors quoted. from the radiatively corrected area under each peak we extract the leptonic width &„, using the relation fo'd~= m' ;, /m'. the results are given in table i. we list our results in terms of relative masses and leptonic widths, since systematic errors in these quanti- ties tend to cancel. our measurements agree with those reported by bohringer et al. ' on the y and &' our results agree with those from doris ' for the mass difference but not for the i;, ratio. because of rather large uncertainties in the contribution of background processes such as & production and two-photon collisions, we do not regard our present measurement of the con- tinuum cross section as definitive. mass differences have been predicted by as- suming that the y, y', and &" are the triplet is, s, and s states of a bb quark pair bound in a phenomenological potential, essentially the same as that responsible for the psion spectrum. when the potential is adjusted to fit masses in the psion region and earlier measurements of the &'-y difference, the predictions for the y"-t mass difference' "range from to mev, table i. measured masses and leptonic widths for the second and third & states, relative to values for the first state, &( . ). the first error is statistical, the second systematic. m-m( . ) (mev) y'( . ), doris (ref. ) y'( . ), doris (ref. ) &'( . ), this experiment &"( . ), this experiment + + . + . + . . + . + . . + . . + . . + . + . . + . + . cleo volume , number physical review letters april all signals were digitized and recorded on tape. this trigger gave an event rate of . hz for a luminosity of pb ' s '. a typical fill of cesr lasts to hours yielding an integrated lumi- nosity of up to - nb '. the integrated luminos- ity for each run was measured by detecting and counting small-angle ( to mrad) collinear bhabha scatter s w ith lead-scintillator sandwich shower detectors. the long-term stability of the luminosity monitor is confirmed by the yield of large-angle bhabha scattering events in the nai array. because of the limited solid angle of the nai array as used, a major fraction of the hadronic e e annihilations gave very few particles in the detector. rather than trying to identify all had- ronic events, which would result in an unaccept- able amount of background, our aim in the analy- sis was to obtain a clean sample through the use of strict event- selection criteria. fundamental in all criteria used was the identification of mini- mum-ionizing hadrons. at normal incidence, minimum-ionizing particles deposit mev in the first four nal layers and - mev in the last layer of a single sector. in all scans one unam- biguous and isolated minimum-ionizing track plus at least two other tracks or showers were required. all data were scanned by physicists and with computer programs. the acceptance criteria for data presented were determined by maximizing detection eff iciency while maintain- ing the background level well below l '%%uo of the continuum cross section. the overall efficien- cies for detecting continuum and y events are, respectively, % and /o. these values are ob- tained by use of the cross sections measured at doris'' (g„„,= . nb at . gev, o ~»&= . nb after correcting for the difference in beam en- ergy spread at cesr and doris). absolute nor- malization was obtained by use of large-angle bhabha-scattering data. the difference in effi- ciencies is due to the fact that & decays have higher multiplicity and sphericity than continuum events. ' the actual number of &, y', and&" events detected above continuum were, respec- tively, , , and . from the continuum around the three ~'s we collected events. the major sources of background were (i) far single beam-wall and beam-gas interactions, (ii) close beam-wall interactions, (iii) close beam-gas interactions, and (iv) cosmic rays. case (i) was trivially removed by the require- ment of an isolated track. cases (ii) and (iii) oc- cur with very small probability of producing pene- trating hadrons at = '~ ' with -gev elec- trons. case (ii), which is more frequent, is also recognizable by tracks crossing azimuthal sector boundaries. case (iv) was rejected by the re- quirement of three tracks. we point out that the minimal residual background does not affect the results presented here. the hadronic yield is presented in fig. , plot- ted in arbitrary units proportional to the ratio of detected events to small-angle bhabha yield. in this way, the energy dependence (- i/e') of the single-photon processes is removed. the hori- . q- c o z.o ~ . - . - i il i ic . . i . ~ w ii ll i ' p ;,e- i i. -ilk .. ~ g 'i]~ „][ii t&l & 'q ii ii k-k-~ &-'-"&~~"& i i i i . . . . .& . e e mass (gev) fig. . the number of hadronic events, normalized to the small-~~pie bhabha yield. the solid line indicates a fit described in the text. cusb Υ( s) launches b physics ( ) chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . rich spectrum of (bb̄) levels observed predicted e j e ic h te n states below threshold still unobserved chris quigg beauty opening ljubljana · . . / charmonium-associated states not pure charmonium all these states near or above threshold near threshold states have possible molecule component “¿. . . ?” need more info if jpc = ++, ¿x ( )? possible p ¿ψ( )? possible s ψ( ), ¿ψ( )? possible hybrids e j e ic h te n when can we find (bb̄) analogues? chris quigg beauty opening ljubljana · . . / quarkonium-associated states: m & threshold: x ( ) etc. mostly narrow, seen in hadronic transitions or decays what are they? quarkonium (+ coupled-channels, thresholds) threshold effects new body plans: quarkonium hybrids (qq̄g) two-quark–two-antiquark states, including dimeson “molecules” tetraquarks diquarkonium · hadroquarkonium and superpositions! (crypto)pentaquarks chris quigg beauty opening ljubljana · . . / cp violation might be large and observable ( – ) chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . https://doi.org/ . / - ( ) - reconstruction of b mesons (cleo, ) pdg: i,j,p still need confirmation! chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . http://pdg.lbl.gov/ /tables/contents_tables_mesons.html mac & mark ii find unexpectedly long b-hadron lifetime ( ) charm lifetimes [fs] d+ : ± d : . ± . ds : ± Λc : ± Ξ+c : ± Ξ c : + − Ωc : + − evidence for small |vcb| ≈ . beauty lifetimes [fs] b+ : ± b : ± bs : ± Λb : ± Ξ−b : ± Ξ b : ± Ωb : + − chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . b -b̄ mixing: the golden event from argus ( ) large mixing ; large mt ua same-sign dimuons ; b s – b̄ s mixing ( ) chris quigg beauty opening ljubljana · . . / https://doi.org/ . / - ( ) - https://doi.org/ . / - ( ) - b properties imply top-quark partner must exist ( ) lb ≡ i l − qb sin θw, rb ≡ i r − qb sin θw Γ(z → bb̄) measures (l b + r b ), a (bb̄) peak (l b −r b )/(l b + r b ), le fb asym a(bb̄) ∝ (rb −lb) i l = − ; i r = chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevd. . observation of large cp violation in b decays (babar & belle, ) sin β ≈ . sin φ ≈ . chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . observation of b s – b̄ s oscillations (cdf, ) ∆ms ≈ . ps− chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . precision tests of the ckm paradigm − . − . ρ − . − . η γ β α sm∆ dm∆ d m∆ k ε cbv ubv summer )σpull ( | ud |v . ) e b(k . ) e b(k . ) μ b(k . )k τb( . not lattice | cd |v . not lattice | cs |v . )νlπ →b(d . )νkl→b(d . )ν τ→ s b(d . )νμ→ s b(d . )νμ→b(d . semilep | cb |v . semilep | ub |v . )ντ→b(b . dmΔ . smΔ . kε . βcos . βsin . α . γ . s φ . μμ→sb . . . . summer ckm f i t t e r chris quigg beauty opening ljubljana · . . / http://www.utfit.org/utfit/resultssummer sm http://ckmfitter.in p .fr/www/results/plots_summer /ckm_res_summer .html reconstruction of bc meson (cdf, ) m(bc ) = . ± . mev (test of lattice qcd prediction) chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . mesons with beauty and charm: stress test for nrqm, lqcd bc : weak decays only b → c c → s bc̄ → w− bc → j/ψπ: (qq̄) transmutation rich (bc̄) excitation spectrum; interpolates j/ψ, Υ ( = masses) excited states below bd → bc + . . . bc ( s) → bc ( s) + ππ p states: γ transitions many states observable at lhc, teraz update: eichten & cq ( ) using “frozen-αs” potential, new approach to spin splittings m as s [m ev ] – narrow levels chris quigg beauty opening ljubljana · . . / http://arxiv.org/abs/arxiv: . http://arxiv.org/abs/arxiv: . observing the bc spectrum: ππ transitions combine predicted production rates (bcvegpy . ) with calculated branching fractions to obtain expectations for ππ transition rates ; peak heights: b∗′c /b ′ c ≈ . m b∗c → /γbc unobserved [m(b∗′c ) −m(b′c )] − [m(b∗c ) −m(bc )] ≈− mev: b∗′c lower peak s → ππ+ s transitions observed by atlas, cms, lhcb cms separation: − mev d σ /d m [n b /m ev ] . . . . m(bcπ +π–) [mev] chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevd. . https://doi.org/ . /physrevlett. . observing the bc spectrum: e transitions e spectroscopy in the (bb̄) family: lhc experiments discovered χ′′b ,χ ′′ b . incentive for the search: s → p and p → s transitions, assuming missing b∗c → bc /γ in the reconstruction. s, p yields ≈ × p → s lines, but higher γ energies may aid detection. p ( ) → b∗c γ( mev) encourage search for ( , )p(bc̄). k [mev] σ b [n b/ m ev ] . . . . . . . . chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . mesons with beauty and charm: states above flavor threshold s states above threshold have significant decay widths p states just below threshold; j = may have significant mixing chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . strong dynamics greatly simplifies for mq � Λqcd symmetry independent of dynamics of light degrees of freedom heavy-light systems: (cq̄), (bq̄), (cqq), (bqq), (ccq), (cbq), (bbq) (q = u,d,s) hqet: systematic expansion in powers of Λqcd/mq hqs relations among spectra in [(cq̄), (bq̄), (ccq), (bcq), (bbq)] and [(cqq), (bqq)] qed analogue: hydrogen atom (e−p+) nonrelativistic (qq̄): bound-state masses m≈ mq nrqcd: systematic expansion in powers of v/c quarkonium systems: (cc̄), (bb̄), (bc̄) heavy quark velocity: pq/mq ≈ v/c � binding energy: mq −m≈ mqv /c qed analogs: positronium (e+e−), “true” muonium (µ+µ−), muonium (µ+e−) chris quigg beauty opening ljubljana · . . / heavy quark symmetry ⇒ stable heavy tetraquarks qiqjq̄kq̄l (qq) q̄ q̄ (qq) q̄ q̄ (qq) q̄ q̄ q̄ q̄ q q hqs relates dhtq mass to masses of qqq, qqq, qq̄. lightest bbūd̄, bbūs̄, bbd̄s̄ states: (likely) no strong decays. heavier bbq̄kq̄l , ccq̄kq̄l , bcq̄kq̄l → qq̄ + qq̄ might be seen as “double-flavor” resonances near threshold. observing a weakly decaying double-beauty state would establish the existence of tetraquarks and illuminate the role of heavy color- ̄ diquarks as hadron constituents. eichten & cq . chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . hqs relations for ground-state tetraquark masses m(qiqjq̄kq̄l ) −m(qiqjqm) = m(qxqkql ) −m(qxq̄m) + finite-mass corrections rhs is determined from data one doubly heavy baryon observed, Ξcc ; others from model calculations ? lhcb: m(Ξ++cc ) = . ± . mev ?we adopt karliner & rosner, prd , ( ) strong decays (qiqjq̄kq̄l ) → (qiqjqm) + (q̄kq̄lq̄m) ∀ ground states consider decays to pairs of heavy–light mesons case-by-case chris quigg beauty opening ljubljana · . . / https://dx.doi.org/ . /physrevlett. . https://dx.doi.org/ . /physrevd. . expectations for ground-state tetraquark masses, in mev state jp m(qiqjq̄kq̄l ) decay channel q [mev] {cc}[ūd̄] + d+d∗ {cc}[q̄k s̄] + d+d∗+s {cc}{q̄kq̄l} +, +, + , , d+d ,d+d∗ , , , [bc][ūd̄] + b−d+/b d [bc][q̄k s̄] + bsd [bc]{q̄kq̄l} + b∗d/bd∗ / {bc}[ūd̄] + b∗d/bd∗ / {bc}[q̄k s̄] + db∗s {bc}{q̄kq̄l} +, +, + , , bd/b∗d / , , {bb}[ūd̄] + b−b̄∗ − {bb}[q̄k s̄] + b̄b̄∗s /b̄sb̄∗ / − {bb}{q̄kq̄l} +, +, + , , b−b ,b−b∗ , , , cf. m. karliner & j. l. rosner model, phys. rev. lett. , ( ) [arxiv: . ]. estimate deeper binding, so additional bc and cc candidates. chris quigg beauty opening ljubljana · . . / https://dx.doi.org/ . /physrevlett. . real-world candidates for stable tetraquarks jp = + {bb}[ūd̄] meson, bound by mev ( mev below b−b̄ γ) t {bb} [ūd̄] ( )−→ Ξ bcp̄, b −d+π−, and b−d+`−ν̄︸︷︷︸ manifestly weak! jp = + {bb}[ūs̄] and {bb}[d̄s̄] mesons, bound by mev ( mev below bbsγ) t {bb} [ūs̄] ( )−→ Ξ bc Σ − t {bb} [d̄s̄] ( ) → Ξ bc (Λ̄, Σ ) chris quigg beauty opening ljubljana · . . / unstable doubly heavy tetraquarks resonances in “wrong-sign” (double flavor) combinations dd,db,bb? jp = + t {cc}++ [d̄s̄] ( )→ d+d∗+s : prima facie evidence for non-qq̄ level double charge / double charm (new kind of resonance: no attractive force at the meson–meson level.) also, + t {bb}{q̄kq̄l}( ) ,−,−−, q = + mev + t {bc} [ūd̄] ( ) , q = + mev + t [bc] [ūd̄] ( ) , q = + mev + t {cc} [ūd̄] ( )+, q = + mev aside: d and f cc̄ mesons still to be identified in dd̄, etc. lhcb d candidate ( ) chris quigg beauty opening ljubljana · . . / https:\dx.doi.org/ . /jhep ( ) homework for experiment t . look for double-flavor resonances near threshold. t . measure cross sections for final states containing heavies: qiq̄iqjq̄j . t . discover and determine masses of doubly-heavy baryons. needed to implement hqs calculation of tetraquark masses intrinsic interest in these states: compare heavy–light mesons, possible core excitations resolve Ξ+cc uncertainty (selex/lhcb) t . find stable tetraquarks through weak decays. lifetime: ∼ ps ?? chris quigg beauty opening ljubljana · . . / https://doi.org/ . /physrevlett. . https://arxiv.org/pdf/ . homework for theory t . develop expectations for production. a. ali et al., “prospects of discovering stable double-heavy tetraquarks at a tera-z factory,” arxiv: . → plb. t . refine lifetime estimates for stable states. t . understand how color configurations evolve with qq (and q̄q̄) masses. j.-m. richard, et al., “few-body quark dynamics for doubly-heavy baryons and tetraquarks,” arxiv: . , phys. rev. c , ( ). t . investigate stability of different body plans in the heavy-quark limit. . . . up to (qiqj )(qkql )(qmqn): b = , but qpqqqr color structure? chris quigg beauty opening ljubljana · . . / https://arxiv.org/abs/ . https://doi.org/ . /j.physletb. . . https://arxiv.org/abs/ . https://doi.org/ . /physrevc. . flavor: the problem of identity what makes an electron an electron, a top quark a top quark, . . . ? we do not have a clear view of how to approach the diverse character of the constituents of matter ckm paradigm: extraordinarily fruitful framework in hadron sector but—many parameters: no clue what determines them, nor at what energy scale they are set even if higgs mechanism explains how masses and mixing angles arise, we do not know why they have the values we observe physics beyond the standard model! chris quigg beauty opening ljubljana · . . / flavor: the problem of identity (continued) parameters of the standard model coupling parameters, αs, αem, sin θw parameters of the higgs potential vacuum phase (qcd) quark masses quark mixing angles cp-violating phase charged-lepton masses neutrino masses leptonic mixing angles leptonic cp-violating phase (+ majorana phases?) + arbitrary parameters chris quigg beauty opening ljubljana · . . / questions concerning the problem of identity f . can we find evidence of right-handed charged-current interactions? is nature built on a fundamentally asymmetrical plan, or are the right-handed weak interactions simply too feeble for us to have observed until now, reflecting an underlying hidden symmetry? f . what is the relationship of left-handed and right-handed fermions? f . are there additional electroweak gauge bosons, beyond w± and z ? f . are there additional kinds of matter? f . is charged-current universality exact? what about lepton-flavor universality? chris quigg beauty opening ljubljana · . . / b(s,d) → `+`− search and observation sm: b(bs → µ+µ−) = ( . ± . ) × − b(bd → µ+µ−) = ( . ± . ) × − recent cms: b(bs → µ+µ−) = [ . + . − . ± . (fs/fd )] × − coming: τ(bs → µ+µ−), b(d,s) → e+e− searches chris quigg beauty opening ljubljana · . . / https://indico.cern.ch/event/ /attachments/ / /slides.pdf https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . https://cds.cern.ch/record/ /files/bph- - -pas.pdf k + → π+νν̄ search and observation ( . ± . ) × − % cl: < . × − < . × − @ % clchris quigg beauty opening ljubljana · . . / https://indico.cern.ch/event/ /attachments/ / /cern_seminar_ _ _ .pdf https://doi.org/ . /jhep ( ) searches for flavor-changing neutral currents f . where are flavor-changing neutral currents in quark transitions? in the standard model, these are absent at tree level and highly suppressed by the glashow–iliopouolos–maiani mechanism. they arise generically in proposals for physics beyond the standard model, and need to be controlled. and yet we have made no sightings! why not? bs,d → µ+µ−, k + → π+νν̄, . . . f . can we detect flavor-violating decays h( ) → τ±µ∓, . . . ? f . how well can we test the standard-model correlation among b(k + → π+νν̄), b(bs → µ+µ−), and the quark-mixing matrix parameter γ? chris quigg beauty opening ljubljana · . . / have we found the “periodic table” of elementary particles? pointlike spin- / constituents (r < − m) su( )c ⊗ su( )l ⊗ u( )y→ su( )c ⊗ u( )em f . what do generations mean? is there a family symmetry? f . why are there three families of quarks and leptons? (is it so?) f . are there new species of quarks and leptons? exotic charges? chris quigg beauty opening ljubljana · . . / more questions concerning the problem of identity f . is there any link to a dark sector? f . what will resolve the disparate values of |vub| and |vcb| measured in inclusive and exclusive decays? f . is the × (ckm) quark-mixing matrix unitary? f . why is isospin a good symmetry? what does it mean? f . can we find evidence for charged-lepton flavor violation? f . will we establish and diagnose a break in the sm? f . do flavor parameters mean anything at all? contrast the landscape perspective. f . if flavor parameters have meaning (beyond engineering information), what is the meta-question? chris quigg beauty opening ljubljana · . . / the top quark touches many topics in particle physics t . how well can we constrain vtb in single-top production, . . . ? t . how well can we constrain the top-quark lifetime? how free is t? recent atlas: Γ(t) = . ± . gev (sm . gev) t . are there tt̄ resonances? t . can we find evidence of flavor-changing top decays t → (z,γ)(c,u)? chris quigg beauty opening ljubljana · . . / http://cdsweb.cern.ch/record/ questions about ewsb and the higgs sector h . is h( ) the only member of its clan? might there be others—charged or neutral—at higher or lower masses? h . does h( ) fully account for electroweak symmetry breaking? does it match standard-model branching fractions to gauge bosons? are absolute couplings to w and z as expected in the standard model? h . are all production rates as expected? any surprise sources of h( )? h . what accounts for the immense range of fermion masses? h . is the higgs field the only source of fermion masses? are fermion couplings proportional to fermion masses? µ+µ− soon? how can we detect h → cc̄? e+e−?? (basis of chemistry) h . what role does the higgs field play in generating neutrino masses? chris quigg beauty opening ljubljana · . . / more questions about ewsb and the higgs sector h . can we establish or exclude decays to new particles? does h( ) act as a portal to hidden sectors? when can we measure Γh ? h . can we detect flavor-violating decays (τ±µ∓, . . . )? h . do loop-induced decays (gg,γγ,γz ) occur at standard-model rates? h . what can we learn from rare decays (j/ψ γ, Υ γ, . . . )? h . does the ew vacuum seem stable, or suggest a new physics scale? h . can we find signs of new strong dynamics or (partial) compositeness? h . can we establish the hhh trilinear self-coupling? h . how well can we test the notion that h regulates higgs–goldstone scattering, i.e., tames the high-energy behavior of ww scattering? h . is the electroweak phase transition first-order? see dawson, englert, plehn, arxiv: . ; phys. rep. chris quigg beauty opening ljubljana · . . / https://arxiv.org/abs/ . https://doi.org/ . /j.physrep. . . an exercise for all of us how do you assess the scientific potential for beauty and in general of (a) the high-luminosity lhc? (b) the high-energy lhc? (c) a -tev pp collider (fcc-hh)? (d) a -gev ilc? (e) a circular higgs factory (fcc-ee or cepc)? (f) a -gev clic? (g) a µ+µ− → h higgs factory? (h) lhec / fcc-eh? (or an electron–ion collider?) (i) a muon-storage-ring neutrino factory? (j) a multi-tev muon collider? (k) the instrument of your dreams? chris quigg beauty opening ljubljana · . . / sleeping beauty transposon-mediated asparaginase gene delivery by a nanoparticle platform scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreports sleeping beauty transposon- mediated asparaginase gene delivery by a nanoparticle platform jen-hsuan chang , , kurt yun mou & chung-yuan mou , transgenic genome integration using non-viral vehicles is a promising approach for gene therapy. previous studies reported that asparagine is a key regulator of cancer cell amino acid homeostasis, anabolic metabolism and cell proliferation. the depletion of asparagine would inhibit the growth of many cancer cells. in this study, we develop a nanoparticle delivery system to permanently integrate the asparaginase gene into the genome of human lung adenocarcinoma cells. the asparaginase plasmid and the sleeping beauty plasmid were co-transfected using amine-functionalized mesoporous nanoparticles into the human lung adenocarcinoma cells. the intracellular asparaginase expression led to the cell cytotoxicity for pc and a cells. in addition, the combination of the chemotherapy and the asparaginase gene therapy additively enhanced the cell cytotoxicity of pc and a cells to % and %, respectively. finally, we showed that the stable cell clones were successfully made by puromycin selection. the doxycycline-induced expression of asparaginase caused almost complete cell death of pc and a asparaginase-integrated stable cells. this work demonstrates that silica-based nanoparticles have great potential in gene delivery for therapeutic purposes. non-viral gene therapy vectors are being studied intensively in human gene therapy due to the simplicity of con- struction, customized individual needs and lower costs of production compared to viral gene therapy vectors , . the sleeping beauty (sb) transposon system is a non-viral vector that can mediate stable integration of thera- peutic transgenes into the genomes of treated cells , and provides sustained expression over a long time. gene therapy based on sb has the potential to become an effective component of cancer treatment by transferring genes that cause tumor cell death or that inhibit angiogenesis . the major obstacle to using non-viral vectors in vivo is the delivery to target cancer cells because naked dna has difficulty in cellular uptakes and tumor targeting , . a nanocarrier system for the delivery gene into the specified tumor for cancer therapy would be very desirable for overcoming these barriers . enzymatic therapy has been developed for the treatment of tumors , . asparagine, a semi-essential amino acid in humans, is crucial for the growth of human cancers, and it plays an important role in tumor metabo- lism , . the tumor cells would undergo cell apoptosis when glutamine-dependent asparagine synthesis was sup- pressed , . the asparaginase synthetase is widely expressed in eukaryotic cells, but it is absent or low expressed in several cancer cells, for example, the acute lymphoblastic leukemia , . therefore, enzymatic depletion of aspar- agine is a promising approach for cancer therapy , . avramis and tiwari reported that native and pegylated l-asparaginase could deaminate l-asparagine into aspartic acid and ammonia, killing t-lymphoblastic leu- kemia – . zhang et al. demonstrated that the depletion of asparagine by asparaginase could induce remarkable cytotoxicity and apoptosis in human lung adenocarcinoma cells . note that the most widely utilized asparaginase from e. coli also processes a weak glutaminase activity , which may also contribute to the cancer elimination . likewise, other non-essential amino acids could also be targets of depletion. arginine depletion was used for the treatment of breast cancer , . savaraj et al. studied that arginine deiminase (adi) would lead to the degradation of arginine resulting in cell apoptosis of melanoma . limitations arise from the difficulty of delivering enzymes, including asparaginase, to cells . poor stabil- ity of the protein, the subsequent immune response, endosome trapping, and protein degradation are all prob- lematic issues that are difficult to be addressed in enzyme delivery, limiting its clinical use to liquid cancers . department of chemistry, national taiwan university, taipei, , taiwan. institute of biomedical sciences, academia sinica, taipei, , taiwan. graduate institute of nanomedicine and medical engineering, taipei medical university, no. , wu xinyi street, taipei, , taiwan. correspondence and requests for materials should be addressed to k.y.m. (email: ymou@ibms.sinica.edu.tw) or c.-y.m. (email: cymou@ntu.edu.tw) received: august accepted: july published: xx xx xxxx open https://doi.org/ . /s - - - mailto:ymou@ibms.sinica.edu.tw mailto:cymou@ntu.edu.tw scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ furthermore, periodical delivery of enzymes could be expensive. a better approach would be a gene delivery by nanocarrier to targeted cells that express the therapeutic protein inside or nearby (in the case of amino acid deple- tion) the targeted cells. an exciting recent example is using nanoparticle to carry piggybac transposon system for in situ programming patient-derived t cells with genes encoding disease-specific chimeric antigen receptors (cars) that target leukaemia . mesoporous silica nanoparticles (msn) is a good nanocarriers with its ease of surface functionalization, high surface area (> m g− ) and tunable pore sizes ( . – nm). in addition, msn is non-toxic and have been widely applied to delivery systems – . with further functionalization of pei, endosomal escape of msn can be enhanced by proton sponge effect. herein, we developed the first non-viral gene delivery for asparaginase expression using the sb transposon vectors by polyethyleneimine (pei)-absorbed msn to induce lung cancer cell apoptosis (fig. ). the sb system could efficiently integrate the target gene into the host chromosome for long-term expression both in vitro and in vivo – . prior to this study, our lab has successfully accomplished the transient gene delivery using msn into induced pluripotent stem cells for specific cell-oriented differentiation , . while transient transfections are ideal for certain experimental settings, stable cell lines could be a more reliable approach for long-term observation as well as for in vivo implantation. in this study, we used msn to deliver the sb transposon plasmids and successfully created stable cell lines expressing the asparaginase. the intracellular expression of asparaginase caused significant cell death in two lung cancer adenocarcinoma cells, pc and a . in addition, we found that the asparaginase gene therapy is additive to the common chemotherapy. we expect that the msn-delivered transposon system could be applied in vivo for targeted gene therapy in the future. result and discussion characterization of amine-modified mesoporous silica nanoparticles (msn-nh ). msns were synthesized by base catalyzed sol-gel reaction with cetyltrimethylammonium bromide (ctab) as templates, and -aminopropyltriethoxysilane (aptms) was used to functionalize msns into amine group-functionalized nanoparticles (abbreviated as msn-nh ). a representative transmission electron microscopy (tem) image of msn-nh is shown in fig. a. based on the tem image, the size of msn-nh is . ± . nm with an oval shape. the dynamic light scattering (dls) showed a comparable particle size of . nm (fig. b). the n adsorption-desorption isotherm is shown in fig. c. the pore size determined by barrett-joyner-halenda (bjh) analysis is . nm. the internal pores will be used for carrying tracking fluorescence agents or other small molecule drugs such that they do not interfere with the carrying of the plasmid. the brunauer–emmett–teller (bet) surface area is . m g− . figure d shows the ph-dependent zeta potential of msn-nh . under the physiological condition, the msn-nh particles are positively charged owing to the amine functionalization. the amination weighs . ± . % of the mesoporous silica nanoparticles as determined by thermogravimetric analysis (tga) (fig. s ). the pei was physically adsorbed on the msn-nh . the amount of pei adsorption was determined to be . ± . % by tga. the resulting material pei-adsorbed msn showed no apparent aggrega- tion with a particle size of ~ – nm (table s ). the zeta potential at ph = . was increased up to + . due to the pei adsorption. further complexation of pei-adsorbed msn and the sb plasmids (psb-asnase + sb ) caused no significant aggregations ( . nm) to slight aggregations ( . nm) when increasing the dose of pei from . μg to . μg (table s ). pei-adsorbed msn showed good uptake and low cytotoxicity to human lung cancer cells. for efficient gene delivery, a good cell uptake of nanoparticles with high endosomal escape is critical. we used flow cytometry to quantify the cellular uptake efficiency of the nanoparticles. all particles tested (fm, fmp, and fmpt) showed great cell uptake with the efficiency over % after -hour incubation (fig. ). we then used figure . the nanoparticle delivery of the sleeping beauty transposon system to mediate the asparaginase (asnase) gene integration into cancer cells. two vectors, the transfer vector psb-asnase and the sleeping beauty vector sb , were co-delivered by the pei-absorbed mesoporous silica nanoparticles. the intracellular expression of asparaginase depletes the asparagine supply and causes the cell death. https://doi.org/ . /s - - - scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ confocal microscopy to visualize the endosomal escape of nanoparticles in pc and a cells at various time points (fig. s ). at min, pei-adsorbed fmsn were aggregated around the cell membrane. the nanoparticles co-localized with an early endosome marker eea after min. co-localization decreased after min, suggest- ing that the nanoparticles successfully escaped from the endosomes and resided in the cytoplasm. we further evaluated the cell cytotoxicity caused by the nanoparticles. pc and a cells were treated with pei or pei-absorbed msn, and the cell viability was measured after hr and hr. as expected, the free pei is cytotoxic to the cells with the viability down to ~ % after hr of the treatment (fig. ). interestingly, the pei-adsorbed msn treatment significantly improved the viability to more than % for both pc and a cells. this experiment implicates that the pei was tightly adsorbed on the msn-nh particles, therefore sequestering the cytotoxicity of pei. pei-absorbed msn successfully delivered the sleeping beauty system for asparaginase expression. we next sought to analyze the transfection efficiency using the msn nanoparticles. we co-delivered the sb plas- mids psb-asnase and sb , where the psb-asnase plasmid encodes a doxycycline-inducible asparagine gene and a green fluorescent protein (gfp) reporter gene. the gfp-positive cells were determined by flow cytometry after days of transfection. figure s showed that the transfection efficiencies were . ± . % and . ± . % for pc cells and a cell, respectively, when using msn-nh particles alone. the transfection efficiency was improved to . ± . % and . ± . %, respectively, when pei-absorbed msn particles were used. note that the improvement was due to the pei absorbed on the particles as the cytotoxicity from the free pei was not observed. we have also used two widely utilized commercial transfection reagents pei and lipofectamine , which exhibited inferior efficiencies around – % compared to the pei-absorbed msn. note that the lipofectamine transfection was performed according to the vendor’s protocol. the suboptimal transfection efficiency might be improved by further optimization. for the asparagine quantification, we added doxycycline to induce the asparagine expression after one day of transfection and incubated for days. we quantified the asparaginase expression level by western blot. figure showed that the asparaginase expression levels in pc and a cells were higher than the negative controls by . and . folds. the successful asparaginase induction was also vali- dated by qpcr at the mrna level (fig. s ). genetic delivery of asparaginase is effective for cancer therapy and additive with chemotherapy. previous studies have shown that asparagine was involved in coordinating protein and nucleotide synthesis in certain cancer cells. consequently, their survival and growth are fully dependent on the external supply of aspar- agine. therefore, the asparagine depletion therapy, such as asparaginase, has proved useful for treating certain figure . the amine-modified mesoporous silica nanoparticles (msn-nh ) is homogeneous and well- dispersed in the water solution. (a) representative tem of msn-nh , (b) dls size measurements of msn-nh , (c) n adsorption-desorption isotherm of msn-nh and (d) the ph-dependent zeta potentials of msn-nh . https://doi.org/ . /s - - - scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ malignancies. we first showed that two human lung adenocarcinoma cell lines, pc and a , are sensitive to the asparaginase treatment with ic unit/ml and unit/ml, respectively (fig. s ). two facts should be noted here: (i) pc and a are competent to de novo synthesize asparagine; (ii) the e. coli asparaginase used here has weak glutaminase activity (asparaginase activity/glutaminase activity ~ : ). the exogenous aspar- aginase cytotoxicity could be due to an additive effect of both asparagine and glutamine depletions. next, we sought to use the nanoparticle vehicle to deliver the asparaginase gene with a doxycycline-inducible sb system. the sleeping beauty plasmids psb-asnase and sb were co-delivered by the pei-absorbed msn particles (msn + pei + psb-asnase, abbreviated as mpt). after one day of transfection, doxycycline was added to induce the asparagine expression in the cells. the cell viability was examined after hours of transfection. note that we have tested that the doxycycline treatment alone is not cytotoxic to pc or a cells (fig. s ). as shown in fig. , the viability of the mpt-transfected cells decreased approximately ± . % in pc cells and ± . % in a compared to the untreated cells. note that % pc and % a cell death were found for the pei-absorbed msn treatment alone (data not shown). furthermore, we tested if the asparaginase gene therapy and the chemo- therapy are additive. we used cisplatin or doxorubicin co-treated with the mpt. after the mpt transfection for two days, µm of cisplatin or . µg/ml of doxorubicin was added to the culture medium. the cell viability assay was performed after days. figure showed that the cisplatin treatment alone led to ± . % cell death of pc , whereas the cisplatin and mpt co-treatment increased the death rate to ± . %. similarly, the doxorubicin treatment alone caused only ± . % of a cell death, whereas the doxorubicin and mpt co-treatment greatly improved the cell death to ± . %. the data suggested that our nanoparticles could successfully deliver the asparaginase gene as a potent therapy to the asparagine-sensitive cancer cells, especially when co-treated with chemotherapy. figure . pc and a showed great cellular uptake of the amine-modified mesoporous silica nanoparticles within -hour incubation. fm: fitc-conjugated msn-nh ; fmp: pei-absorbed fmsn; fmpt: t + pei- absorbed fmst; t: psb-asnase + sb . the amount of fmsn was µg/ml, the pei was . µg/ml for pc cells and . µg/ml for a cells. t: psb-asnase + sb . **indicates the statistical differences (**p < . ) compared with controls. figure . the pei-absorbed msn significantly reduced the cytotoxicity of free pei in pc and a cells. mp: pei-absorbed msn; p: free pei. the pc and a cell viability was measured after the treatment of pei and pei-absorbed msn (pei, . µg/ml for pc cells, . µg/ml for a cells, msn: µg/ml) for (a) hr and (b) hr. *and **indicates the statistical differences (*p < . and **p < . ) compared with controls. https://doi.org/ . /s - - - scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ nanoparticles successfully delivered the sleeping beauty system to create the asnase-carried stable cell line. next, we sought to test if the sleeping beauty system delivered by the nanoparticles could successfully create stable cell lines. the psb-asnase plasmid encoded a puromycin resistance gene that could be used for stable cell line selections. after co-transfection of psb-asnase and sb by pei-adsorbed msn for days, we challenged the pc and a cells with . µg/ml puromycin for days. all the survived cells of pc and a (asnase-carried pc and asnase-carried a ) showed clear gfp signals as shown by fluores- cence microscopy (fig. s ). continuous growth of the cells in the absence of puromycin maintained the gfp expression, indicating a stable integration of psb-asnase into the host genome by the sleeping beauty system. figure . the asparaginase gene was successfully delivered and expressed by the pei-absorbed msn transfection in pc and a cells. mpt: t + pei-absorbed msn (t: psb-asnase + sb ). (a) pc cells, and (b) a cells under the treatment of mpt or the non-treatment condition (ctl) for days. figure . the cytotoxicity of the asparaginase gene expression and the chemotherapy is additive in pc and a cells. the cell proliferation assays were demonstrated under the treatments of (a) cisplatin ( . µm) in pc cells and (b) doxorubicin ( . µg/ml) in a cells after the transfection of psb-asnase and sb . *p < . and **p < . . mpt: t + pei-absorbed msn (t: psb-asnase and sb ). https://doi.org/ . /s - - - scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ to investigate the full strength of the asparaginase gene therapy, we performed the asparagine depletion exper- iments with the asnase-carried pc and asnase-carried a stable cells. the time-course cell viability was measured after the asparaginase induction by doxycycline (fig. ). the cell viability was dropped to only . % and . % for the asnase-carried pc cells on day and the asnase-carried a cells on day , respectively. the asnase-carried pc or a cells also showed much higher sensitivity to the exogenous asparaginase treatment compared to the parental pc or a cells (fig. s ). note that the parental pc or a cells were also sensitive to the asparaginase treatment when growing in the asparagine-free dmem medium, which likely reflected the cytotoxicity caused by the glutaminase activity from the asparaginase (fig. s ). interestingly, the rpmi-adapted asnase-carried pc or a are more sensitive to the asparaginase treatment than the dmem-adapted pc or a . we reasoned that the growth of the rpmi-adapted cells might rely more heavily on asparagine than the dmem-adapted cells. asnase-carried cells depleted the environmental asparagine and reduced the cell growth to the neighboring cells. in the previous experiments, we noticed that – % transfection efficiency could lead to – % cell death for pc and a (figs s and ). although a portion of cell death could be contributed by the transfection toxicity (< %), we suspected that the transfected cells might cause additional cell death to the non-transfected cells through the asparagine depletion in the medium. to test this hypothesis, we designed a transwell experiment, in which the inner chamber was seeded with the asnase-carried pc or a stable cells and the outer chamber was seeded with the parental pc or a cells (fig. a). the cell viability of the parental cells in the outer chamber was compared between the conditions with or without the doxycycline induction after hour. the doxycycline-treated experiments showed significant lower cell viability, which is only % and % of the non-treated experiments for pc and a , respectively (fig. b,c). this result supports our hypothesis that the asparaginase induction in the asnase-carried cells not only kills themselves but also effects the viability of the co-cultured parental cells due to the asparagine depletion in the medium. note that the pc and a cells can de novo synthesize asparagine. the asparagine depletion in the medium only slowed down the growth but not killed the cells. expectedly, when performing the transwell experiment in dmem, we observed no cytotoxicity to the outer chamber cells because dmem is an asparagine-free medium (fig. b,c). this neighboring effect is very encouraging for the future in vivo work because perfect transfection efficiency may not be required for effective tumor elimination. conclusions in summary, we have developed a mesoporous silica nanocarrier system that can deliver a sleeping beauty sys- tem, which endows a long-term expression of l-asparaginase for depletion of the amino acid asparagine. we demonstrated the asparaginase gene delivered by the nanoparticles could effectively kill two human lung ade- nocarcinoma cells, pc and a , with great additive effect to common chemotherapy drugs. the nanocarrier system can be improved in several ways for in vivo studies in the future: (i) a surface functionalization of msns by cancer-targeting ligands can be easily executed by surface silane coupling reactions. also, the msn particles can be further functionalized with polyethylene glycol (peg) to increase its blood circulation. (ii) the msns can be synthesized into specific sizes to accumulate in the tumor by enhanced permeability and retention (epr) effect. the newly formed tumor has fenestrated blood vessel with hyper-permeability. the nanoparticle size is chosen such that they can take advantage of the enhanced permeability and retention (epr) effect based on the hyper-permeability of tumor vessels, which allows certain sizes of nanoparticles to accumulate in the tumor. (iii) hollow silica nanospheres (hsn) may be used instead of msns for more elaborate loadings of internal cargos. recently, ma et al. improved the efficiency of a sb/carrier system by loading in situ pcr-amplified sleeping beauty transposon . figure . the asnase-carried stable cell lines pc and a showed severe cell death after inducing the asparaginase expression. (a) after the asparaginase induction by doxycycline, the cell viability of the asnase- carried stable cell line pc (pc -mpt) was measured from day to day . the signal was normalized to the parental pc cells. (b) the same experiment for a . https://doi.org/ . /s - - - scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ a note about the amino acid depletion method in cancer therapy should also be mentioned here. because some cancer cells down-regulated the synthesis of asparagines, they have to import asparagine from extracellular media. the delivery of our nanocarrier system for amino acid depletion needs only to the local environment of the cancer cell. once asparagine molecules are efficiently removed from the local microenvironment of cancer, the cancer cells will die from starvation. this is especially suitable for our sb system since the expression of asnase is localized to tumor cells and effective for long term. finally, we would like to comment that our nanocarrier/gene delivery platform may be useful for another major class of unmet medical need, e.g. the lysosomal storage disease (lsd), such as fabry disease. lsds are inherited diseases in which lysosomal enzymes are deficient and there is no cure . present approaches of enzyme replacement therapy (ert) are very inefficient and expensive because of the biological barriers for enzyme deliv- ery . an approach of long-term production of enzymes intracellularly by the nanocarrier/sb system would be most desirable. the encouraging results of this report may make this goal closer. experimental section synthesis of amine-group conjugated mesoporous silica nanoparticles. . m of c tab (hex- adecyltrimethyl ammonium bromide) was dissolved in . m of ammonia solution under constant agitation ( min, °c). then, ml of . m teos (tetraethoxysilane) ethanol solution was added with stirring for hr at °c, and then ml of . m teos ethanol solution was added with stirring ( min, °c). next, μl of ( -aminopropyl)trimethoxysilane (aptms) was added with stirring ( min), and the solution was standing for hrs. then, μl of peg-silane (mw ) and μl of ammonia solution ( %) was added with stirring ( hr, °c). the amine-functionalized msn-nh was collected by centrifugation ( min, rpm), washed, and redispersed with deionized water and ethanol several times. next, the c tab was extracted by nh no ( . m of nh no ethanol solution) twice. finally, the amine group-conjugated msn-nh was collected by centrifugation ( min, rpm). labeling of ritc-psb-asnase. to study the plasmid release, the rhodamine isothiocyanate (ritc)-labeled psb-asnase was prepared. μl of psb-asnase ( . μg psb-asnase/μl h o) was mixed with μl of ritc ( mg ritc/ml etoh). after the solution was stirred at °c overnight, the unreacted ritc was removed by dialysis for three days and the ritc-psb-asnase was collected. molecular cloning. the sb transfer plasmid (psb) was digested with the restriction enzyme sfii. the inserts were prepared by designing the pcr primers (table s ) of asparaginase (asnase) gene and using escherichia coli cells as the template to amplify the dna fragment of asnase gene (fig. s ). next, the inserts were assembled with the digested psb vector by the nebuilder hifi dna assembly master mix (neb, e s). the final plasmid was sequencing verified and denoted as psb-asnase. cell uptake analysis. the uptake efficiency of nanoparticles was determined by facscalibur flow cytom- eter and cellquest pro software (becton dickenson, mississauga, ca). fitc-conjugated msn (fmsn) were synthesized for detection of the fluorescence signal. the µg/well fmsn and pei-absorbed fmsn (pei: . µg for pc cells and . µg for a cells) were incubated with cells ( × /well) for hr and then washed by phosphate-buffered saline (pbs). figure . the asnase-carried pc or a stable cells depleted the asparagine in the medium and caused the cytotoxicity to the co-cultured parental pc or a cells. (a) the experimental design of the transwell co-culture assay. the doxycycline-inducible asnase-carried pc or a stable cells were seeded in the inner chamber, and the parental pc or a cells were seeded in the outer chamber. after hours of the asparaginase induction by doxycycline, the cell viability was assayed for the parental cells in the outer chamber. (b) the cell viability was compared between the doxycycline-treated and the non-treated experiments for pc in rpmi or dmem medium. (c) same as (b) for a . https://doi.org/ . /s - - - scientific reports | ( ) : | https://doi.org/ . /s - - - www.nature.com/scientificreportswww.nature.com/scientificreports/ cellular cytotoxicity of pei-absorbed msn. × of pc or a cells per well were seeded in -well plates for h before cytotoxicity assays. to evaluate the in vitro cytotoxicity of pei and pei-absorbed msn, cells were incubated with pei-absorbed msn ( . μg of pei mixed with µg of msn) in -well plates for hr and hr with regular growth medium. the cell was followed by the incubation of wst- ( . mg ml− ) for hr at °c for the cell cytotoxicity assay. the amount of orange formazan dye generated by the living cells was propor- tional to the number of the living cells, and the absorbance at nm was measured by using a microplate reader (biotek synergy h hybrid reader). cell culture, transfection, and cell selection. the human lung adenocarcinoma cells (pc ) and the human alveolar adenocarcinoma cell (a ) were maintained in rpmi supplemented with mm glu- tamine, % fetal bovine serum (fbs, gibco), u/ml penicillin and µg/ml streptomycin (gibco) at °c in a % co atmosphere. cells were passaged every days. before transfection, the cells were seeded into -well dishes at a density of × cells/well. . μg of psb-asnase and . µg of sb plasmid were mixed with µg of msn for mins, followed by addition of pei for mins (pei, . µg for pc cells and . µg for a cells). the complexes were then added to cells and incubated for hrs. after a wash step with pbs, the cells were cultured at °c in rpmi supplemented with % fbs and µg/ml doxycycline. after three days of transfections, . µg/ml of puromycin was used to select for days to generate the stable cell clones. immunofluorescence staining. immunofluorescence staining was used to identify early endosome in pc cells. after fmsn incubated with pc cells for , and min, the pc cells were washed with pbs and fixed with % paraformaldehyde for min. the pc cells were then permeabilized with . % np- for min, and then the cells were subsequently incubated overnight with the early endosome marker eea antibody (abcam, ab ). the cells were then washed with pbs and treated with the fluorescence-conjugated secondary antibody (jakson immunoreseatch, - - , - - ) and dapi. the stained pc cells were observed using a fluorescence microscope. western blot. × of cells were seeded in cm dishes and transfected with psb-asnase and sb using pei-absorbed msn for hr. after days, cells were trypsinized and lysed using μl of m-per® mammalian protein extraction reagent ( , thermo fisher) on ice for min. the lysates were purified by centrifugation ( rpm, min). protein concentrations were quantified using a pierce™ bca protein assay kit ( , thermo fisher). the protein was denatured at °c for min and loaded into the sds-page gel. proteins were transferred using the te mighty small transfer tank (hoefer) onto pvdf membranes (millipore, ipvh ). the membrane was blocked with % milk for hr followed by the primary antibody ( : of anti-asnase (abcam, ab ), : of anti-actin (millipore, mab )) diluted in % milk followed by : of hrp-conjugated secondary antibody ( : dilution of cell signaling, # , # ). the signal was detected by adding the ecl-plus western blotting substrate and a luminescence imaging system. transwell co-culture experiments. the asnase-carried pc or a cells were co-cultured with the parental pc or a cells in a transwell setup (falcon cell culture insert, # , -well, pore size μm). a number of , asnase-carried and parental cells were seeded in the inner chamber and the outer chamber, respectively, in a six-well plate. after hours, μg/ml doxycycline was added to the medium. a control exper- iment without the doxycycline treatment was also performed. after hours of the doxycycline treatment, the cell viability was measured for the parental cells in the outer chamber by the wst assay. the cell viability was compared between the doxycycline-treated and the non-treated experiments for pc and a cells. data availability the datasets generated during the current study are available from the corresponding author on reasonable re- quest. references . yin, h. et al. non-viral vectors for gene-based therapy. nat. rev. genet. , – , – ( ). . schatzlein, a. g. non-viral vectors in cancer gene therapy: principles and progress. anti-cancer drug , – ( ). . ivics, z., hackett, p. b., plasterk, r. h. & izsvak, z. molecular reconstruction of sleeping beauty, a tc -like transposon from fish, and its transposition in human cells. cell , – ( ). . ohlfest, j. r., lobitz, p. d., perkinson, s. g. & largaespada, d. a. integration and long-term expression in xenografted human glioblastoma cells using a plasmid-based transposon system. mol. ther. , – ( ). . aronovich, e. l., mcivor, r. s. & hackett, p. b. the sleeping beauty transposon system: a non-viral vector for gene therapy. hum. mol. genet. , r –r ( ). . zhang, y., satterlee, a. & huang, l. in vivo gene delivery by nonviral vectors: overcoming hurdles? mol. ther. , – ( ). . al-dosari, m. s. & gao, x. nonviral gene delivery: principle, limitations, and recent progress. aaps j. , – ( ). . wang, k., kievit, f. m. & zhang, m. q. nanoparticles for cancer gene therapy: recent advances, challenges, and strategies. pharmacol. res. , – ( ). . holcenberg, j. s. enzyme therapy of cancer, future studies. cancer trea. rep. 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( ). . converse, a. d. et al. counterselection and co-delivery of transposon and transposase functions for sleeping beauty-mediated transposition in cultured mammalian cells. bioscience rep. , – ( ). . ma, k. et al. targeted delivery of in situ pcr-amplified sleeping beauty transposon genes to cancer cells with lipid-based nanoparticle-like protocells. biomaterials ( – ), – ( ). . chen, w., tsai, p.-h., hung, y., chiou, s.-h. & mou, c.-y. nonviral cell labeling and differentiation agent for induced pluripotent stem cells based on mesoporous silica nanoparticles. acs nano , – ( ). . chang, j. h., tsai, p. h., chen, w., chiou, s. h. & mou, c. y. dual delivery of sirna and plasmid dna using mesoporous silica nanoparticles to differentiate induced pluripotent stem cells into dopaminergic neurons. j. mater. chem. b , – ( ). . chang, f. p., chen, y. p. & mou, c. y. intracellular implantation of enzymes in hollow silica nanospheres for protein therapy: cascade system of superoxide dismutase and catalase. small , – ( ). . seregin, s. s. & amalfitano, a. gene therapy for lysosomal storage diseases: progress, challenges and future prospects. curr. pharm. design , – ( ). . schultz, m. l., tecedor, l., chang, m. & davidson, b. l. clarifying lysosomal storage diseases. trends neurosci. , – ( ). acknowledgements this research was funded by national taiwan university, academia sinica (as-cda- -l ), and the ministry of science and technology of taiwan (most - -m- - -my ). author contributions j.-h. chang designed the experiments and performed the laboratory experiments, including characterization of materials, cell experiments and analysis of the results. j.-h. chang wrote the paper and all authors discussed the results and commented on the manuscript. k.y.m. and c.-y. mou conceived and supervised the project. all authors have seen the manuscript at all stages, discussed the data and agreed to the content. additional information supplementary information accompanies this paper at https://doi.org/ . /s - - - . competing interests: the authors declare no competing interests. publisher’s note: springer nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. open access this article is licensed under a creative commons attribution . international license, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the cre- ative commons license, and indicate if changes were made. the images or other third party material in this article are included in the article’s creative commons license, unless indicated otherwise in a credit line to the material. if material is not included in the article’s creative commons license and your intended use is not per- mitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. to view a copy of this license, visit http://creativecommons.org/licenses/by/ . /. © the author(s) https://doi.org/ . /s - - - https://doi.org/ . /gene. https://doi.org/ . /s - - - http://creativecommons.org/licenses/by/ . / sleeping beauty transposon-mediated asparaginase gene delivery by a nanoparticle platform result and discussion characterization of amine-modified mesoporous silica nanoparticles (msn-nh ). pei-adsorbed msn showed good uptake and low cytotoxicity to human lung cancer cells. pei-absorbed msn successfully delivered the sleeping beauty system for asparaginase expression. genetic delivery of asparaginase is effective for cancer therapy and additive with chemotherapy. nanoparticles successfully delivered the sleeping beauty system to create the asnase-carried stable cell line. asnase-carried cells depleted the environmental asparagine and reduced the cell growth to the neighboring cells. conclusions experimental section synthesis of amine-group conjugated mesoporous silica nanoparticles. labeling of ritc-psb-asnase. molecular cloning. cell uptake analysis. cellular cytotoxicity of pei-absorbed msn. cell culture, transfection, and cell selection. immunofluorescence staining. western blot. transwell co-culture experiments. acknowledgements figure the nanoparticle delivery of the sleeping beauty transposon system to mediate the asparaginase (asnase) gene integration into cancer cells. figure the amine-modified mesoporous silica nanoparticles (msn-nh ) is homogeneous and well-dispersed in the water solution. figure pc and a showed great cellular uptake of the amine-modified mesoporous silica nanoparticles within -hour incubation. figure the pei-absorbed msn significantly reduced the cytotoxicity of free pei in pc and a cells. figure the asparaginase gene was successfully delivered and expressed by the pei-absorbed msn transfection in pc and a cells. figure the cytotoxicity of the asparaginase gene expression and the chemotherapy is additive in pc and a cells. figure the asnase-carried stable cell lines pc and a showed severe cell death after inducing the asparaginase expression. figure the asnase-carried pc or a stable cells depleted the asparagine in the medium and caused the cytotoxicity to the co-cultured parental pc or a cells. ivics.pm sleeping beauty curr. issues mol. biol. ( ) : - . online journal at www.cimb.org *for correspondence. email zivics@mdc-berlin.de. © caister academic press. offprints from www.cimb.org the sleeping beauty transposable element: evolution, regulation and genetic applications zoltán ivics , christopher d. kaufman , hatem zayed , csaba miskey , oliver walisko and zsuzsanna izsvák , max delbrück center for molecular medicine, robert rössle str. , d- , berlin, germany institute of biochemistry, biological research center of the hungarian academy of sciences, szeged, hungary abstract members of the tc /mariner superfamily of transposable elements isolated from vertebrate species are inactive due to the accumulation of mutations. a representative of a subfamily of fish elements estimated to be last active > million years ago has been reconstructed, and named sleeping beauty (sb). this element opened up new avenues for studies on dna transposition in vertebrates, and for the development of transposon tools for genetic manipulation in important model species and in humans. multiple transposase binding sites within the terminal inverted repeats, a transpositional enhancer sequence, unequal affinity of the transposase to the binding sites and the activity of the cellular hmgb protein all contribute to a highly regulated assembly of sb synaptic complexes, which is likely a requirement for the subsequent catalytic steps. host proteins involved in double-strand dna break repair are limiting factors of sb transposition in mammalian cells, underscoring evolutionary, structural and functional links between dna transposition, retroviral integration and v(d)j recombination. sb catalyzes efficient cut-and-paste transposition in a wide range of vertebrate cells in tissue culture, and in somatic tissues as well as the germline of the mouse and zebrafish in vivo, indicating its usefulness as a vector for transgenesis and insertional mutagenesis. the evolutionary life-cycle of dna transposons large fractions of genomes can be composed of transposable element sequences. the human genome project revealed that approximately % of the human genome is transposon-derived (i. h. g. s. c. ); nevertheless, most of these elements are inactive. three evolutionary processes were proposed to describe the “life- cycle” of a dna transposon in a genome (lohe et al., ; hartl et al., ). in the absence of selection pressure, “vertical inactivation” leads to accumulation of mutations in the transposon sequence. dna transposons consist of two components: a transposon dna and a recombinase that can trans-activate the transposon. since transposase- defective (nonautonomous) elements can be as good “jumpers” as the autonomous copies, the ratio of autonomous to nonautonomous elements decreases with time, eventually resulting in the complete disappearance of active transposons in a given genome: a process termed “stochastic loss”. “horizontal transfer” is able to rescue the active transposon by invasion of the germline of a naive genome, so that the cycle can start over again. consequently, dna-transposons can be viewed as transitory components of genomes which, in order to avoid extinction, must find ways to establish themselves in a new host. due to these processes, not a single autonomous element has been isolated from vertebrates, hindering studies on the basic mechanisms of dna transposition, and prohibiting the development of transposon-based tools for vertebrate genetics. awakening of sleeping beauty, an ancient tc -like transposon from fish from all dna-transposons found so far in vertebrates, members of the tc /mariner superfamily from teleost fish are by far the best characterized (goodier and davidson, ; radice et al., ; izsvák et al., ; ivics et al., ). in contrast to the p element transposon which is restricted to the drosophila genus (rio et al., ), tc / mariner elements are extremely widespread in nature (plasterk et al., ). this indicates that host requirements for tc /mariner transposition are not that tight and that elements might be promiscuous in evolutionary terms. molecular phylogenetic analyses have shown that the majority of the fish tc -like elements can be classified into three major types: zebrafish-, salmonid- and xenopus txr- type elements (ivics et al., ), of which the salmonid subfamily is probably the youngest and thus most recently active. all of the fish elements isolated so far appear to have undergone vertical inactivation, and accumulated several mutations in their transposase genes. in an attempt to derive an active tc -like transposon from vertebrates, we have analyzed the salmonid subfamily of elements that was presumed to be active more than - million years ago, and appeared to have been able to invade different fish genomes through horizontal transmission (ivics et al., ). we reasoned that a consensus sequence generated from a sequence alignment of defective copies isolated from different fish genomes would likely represent an active archetypal sequence. we engineered this sequence to reconstruct an active ancestral element, which was named sleeping beauty (sb) (ivics et al., ). the sb transposon system consists of two main functional components: the transposase encoded by a synthetic gene, and a cloned, nonautonomous, salmonid-type element that ivics et al. carries the inverted repeats of the transposon that are recognized by the transposase (figure a). the two components of the sb system have to at least temporarily coexist in a cell for transposition to occur. we established an in vivo transposition assay to detect sb transposition events from plasmids to the chromosomes of vertebrate cells (ivics et al., ). the assay, shown in figure b, is based on cotransfection of a transposon donor plasmid and a transposase-expressing helper plasmid into cultured cells. the transposable element carries an antibiotic resistance gene such as neo, so that inserted transposons that express their genes confer an antibiotic- resistant phenotype to cells. cells are then placed under g- selection, and resistant colonies counted. the ratio between numbers obtained in the presence and absence of transposase is the readout of the assay, and is a measure of the efficiency of transposition. the result of a typical experiment in human hela cells is shown in figure b. horizontal gene transfer in the lab: transposition of sleeping beauty in diverse vertebrate cells in plants, transposable elements of the ac/ds and spm families have been routinely introduced into heterologous species (haring et al., ). no obvious barriers existed a priori that would restrict the activity of sb in heterologous species: the expression of transposase in any host should be sufficient to trigger transposition. the observation that both tc (vos et al., ) and mariner transposases (lampe et al., ) produced in e. coli are able to catalyze transposition in vitro, and the several successful gene transfer experiments with various tc /mariner elements into heterologous hosts (reviewed in plasterk et al., ) seemed to support this assumption. the ancient salmonid transposon was clearly able to invade certain teleost fish species; nevertheless, it is absent from other vertebrate species, suggesting some limitations to its spread. a “zoo” figure . sleeping beauty transposition in cultured vertebrate cells. (a) schematic representation of the two major components of the sleeping beauty transposable element system. in nature, the terminal inverted repeats (black arrows) flank a gene encoding the transposase (tnpase). the inverted repeats of sb elements have a characteristic structure (ir/dr), and contain two binding sites for the transposase (white arrows) per repeat. the transposase has an n-terminal, paired-like dna-binding domain consisting of two helix-turn-helix motifs, pai and red, with a grrr-motif (at-hook) between them. the red subdomain overlaps with a nuclear localization signal (nls), which is followed by the catalytic domain responsible for the dna cleavage and joining reactions and characterized by the conserved dde signature. the pai subdomain recognizes the '-, whereas the red subdomain recognizes the '-half of the bipartite recognition sequence. a sequence comparison between the outer and inner binding sites and the hdr enhancer is shown. (b) assay for transposition in cultured cells. under experimental conditions the two components of the transposon system are separated. a selectable marker such as an antibiotic resistance gene (neo) is cloned between the inverted repeats of the sb transposon. transposon donor plasmids are introduced into cells together with transposase-expressing helper plasmids by transfection. in control transfections, a plasmid expressing a nonrelevant protein (β-gal) substitutes for the transposase. cells are placed under antibiotic selection; only cells that express the antibiotic resistance gene due to chromosomal integration survive. resistant cells give rise to colonies that can be harvested for dna analysis, picked and expanded into larger cultures or stained for documentation. shown are two petri dishes with stained human hela cell colonies obtained in the absence (upper dish) or in the presence (lower dish) of transposase. the marked difference in the numbers of resistant clones is due to transposition of the marked transposable elements into chromosomes. β sleeping beauty experiment, in which sb’s activity was tested in cells of different vertebrate classes, raised some interesting points (izsvák et al., ). cell lines from different fish species, from mouse, human, frog, chick, sheep, cow, dog, rabbit, hamster and monkey were tested, using the in vivo transposition assay described above. as summarized in table , sb was able to increase the frequency of transgene integration in all of these cell lines, indicating that sb is active in most (if not all) vertebrate species. we found extensive variation in the extent to which transposase stimulates integration between different species and even between different cell lines of the same species (table ). unexpectedly, evolutinary distance of the recipient species (as compared to bony fishes from which sb originates) was not the main factor affecting transpositional efficieny, since the highest activity was observed in human cells. one factor that can clearly affect the activity of sb in these experiments is the varying levels of transfectability of the different cell lines, which can influence both the amount of transposase and the number of available transposon substrate molecules per cell. this might explain the difference in transpositional efficiency in cells derived from the same species. furthermore, despite the widespread nature of tc /mariner elements, the involvement of certain host factors in transposition cannot be ruled out. interaction of such factors with the transpositional machinery might lead to different efficiencies of transposition in different species and/or cells. indeed, we have found that the relative inefficiency of transposition correlated with a decreased level of precision of transposon integration in some cell lines (izsvák et al., ). another line of experiments appoached the question from the other direction. when tested under identical experimental conditions in the same cell line, sleeping beauty outperformed other members of the tc /mariner superfamily (fischer et al., ). sb activity was about - -fold higher in human cells compared to tc , tc , the mos and himar mariner elements and minos (fischer et al., ; and our own unpublished results). one possible explanation for the differences is that the activity of a transposon might depend on the actual phase of its evolutionary life cycle. the three main periods in the cycle are: ) the invasion of a naïve genome, ) establishment of the transposon in the new host and ) propagation, accumulation of mutations and extinction. it is possible, that a transposable element has the highest activity in the period of invasion and, subsequently, certain regulatory mechanisms are established between the host and the transposon resulting in low(er) transpositional activity. the available data suggest that transposons begin to accumulate mutations after their arrival into a genome. transposons are not always successful, they can fail to establish themselves in a given genome, and might be unable to achieve high copy numbers, or can even “die out” without successfully invading a new host. accordingly, the sleeping beauty transposon, which is presumed to represent an ancient element capable of invading new genomes through horizontal transmission, might have a higher intrinsic transpositional activity than the other elements that were tested. nevertheless, hyperactive mutants of the sb transposase can be selected (unpublished results), indicating that a plateau of possible intrinsic activity has not yet been reached. another explanation for the observed difference in the respective transpositional activities of different elements can be their different abilities to interact with host factors. since sb is a vertebrate transposon, it might be better “tuned” to a vertebrate cellular environment than elements originating from invertebrates. the structure of the sleeping beauty transposon conserved protein domains in the transposase the overall domain structure of the transposase is conserved in the entire tc /mariner superfamily (plasterk et al., ). specific substrate recognition is mediated by an n-terminal, bipartite dna-binding domain of the transposase (figure a) (vos and plasterk, ; pietrokovski and henikoff, ; izsvák et al., ). this dna-binding domain has been proposed to consist of two helix-turn-helix (hth) motifs, similar to the paired domain of some transcription factors in both amino acid sequence and structure (franz et al., ; vos and plasterk, ; ivics et al., ). the modular paired domain has evolved versatility in binding to a range of different dna sequences through various combinations of its subdomains (pai+red) (czerny et al., ). the nucleotide sequences recognized by the composite paired domain are degenerate, the dna- binding specificity is relaxed (pellizzari et al., ). the origin of the paired domain is not clear, but phylogenetic analyses indicate that it might have been derived from an ancestral transposase (breitling and gerber, ). partially overlapping with the red subdomain in the transposase is a nuclear localization signal (nls in figure a), flanked by phosphorylation target sites of casein kinase ii (ivics et al., ). phosphorylation of these sites is a potential checkpoint in the regulation of transposition. the nls indicates that these transposons, unlike murine retroviruses, can take advantage of the receptor-mediated transport machinery of host cells for nuclear uptake of their table . horizontal gene transfer in the laboratory. summary of tissue culture transformation experiments using sleeping beauty transposons as vectors. transpositional efficiency is expressed as the ratio between the number of g- -resistant cell clones obtained in the presence versus in the absence of sb transposase. + - -fold, ++ - -fold, +++ - -fold, ++++ - -fold, +++++ > -fold. ivics et al. transposases. a characteristic grpr-like motif (grrr) between the two hth motifs (figure a) is similar to an at-hook (izsvák et al., ), responsible for minor groove interactions in the hin invertase of salmonella (feng et al., ) and in the rag recombinase of v(d)j recombination (spanopoulou et al., ) the catalytic domain of the transposase, responsible for the dna cleavage and joining reactions, is characterized by a conserved amino acid triad, the dde motif (figure a), which is found in a large group of recombinases, including retrotransposon and retrovirus integrases, bacterial is element transposases (doak et al., ) and rag (kim et al., ; landree et al., ). within the catalytic domains of tc -like transposases, a conserved glycine-rich subdomain can be found (ivics et al., ). the function of this subdomain is unknown. in addition to the dde-containing transposases and integrases (dyda et al., ; davies et al., ), crystallographic analyses of the catalytic domains of proteins whose functions are not obviously related to transposition, such as rnaase h (katayanagi et al., ) or ruvc (ariyoshi et al., ) have revealed a remarkably similar overall fold. the existence of a common structural motif that catalyses polynucleotidyl transfer reactions in diverse biological contexts suggests that the different specificities in binding to dna might have evolved by the apparent acquisition of different dna-binding domains in the evolution of dde recombinases (capy et al., ). structure of the transposon transposons are bracketed by terminal inverted repeats that contain binding sites for the transposase. tc /mariner elements have a roughly uniform size of approximately . - . kb, indicating a natural selection in genomes for this particular size. sleeping beauty has a pair of transposase- binding sites at the ends of the - bp long inverted repeats (irs). within each ir of sb, there are two transposase binding sites that contain short, - bp direct repeats (drs). this special organization of inverted repeat, termed ir/dr (figure a), is an evolutionarily conserved feature of a group of tc -like elements, but not that of the tc element itself (izsvák et al., ; plasterk et al., ). the ir/dr subgroup is represented by the minos, bari , s elements in flies (franz and savakis, ; merriman et al., ; moschetti et al., ), quetzal elements in mosquitos (ke et al., ), txr elements in frogs (lam et al., ) and at least three tc -like transposon subfamilies in fish (ivics et al., ). the spacing of about bp between the outer and inner binding sites is conserved in all elements within the ir/dr group, but the actual dna sequences are not similar, suggesting convergent evolution of the ir/dr-type repeats. the ir/dr group significantly differs from tc or the mariner elements that are more simple and have repeats of less than bp and a single transposase binding site per repeat. all four binding sites within the ir/dr structure are required for sb transposition (izsvák et al., ). the four binding sites are not identical, the outer ones are longer by two base pairs (figure a). the irs are not identical either; the left ir contains a sequence motif called the hdr, which resembles the '- half of the transposase binding sites (figure a) (izsvák et al., ). a construct containing two left irs transposes better than the wild-type transposon, but another version that has two right irs has very poor mobility, indicating that the left and right irs are functionally distinct (izsvák et al., ). mechanism of transposition the transposase protein and the inverted repeats together engage in a series of molecular events that lead to the excision of the element from its dna context and reintegration into a different locus, a process termed cut- and-paste transposition. the transposition process can arbitrarily be divided into at least four major steps: ) binding of the transposase to its sites within the transposon irs; ) formation of a synaptic complex in which the two ends of the elements are paired and held together by transposase subunits; ) excision from the donor site; ) reintegration at a target site. on the molecular level, mobility of dna-based transposable elements can be regulated by imposing constraints on transposition. one important form of transpositional control is represented by regulatory “checkpoints”, at which certain molecular requirements have to be fulfilled for the transpositional reaction to proceed. these requirements can operate at any of the four different stages of transposition listed above, and can be brought about by both element-encoded and host- encoded factors. specific dna-binding by the sleeping beauty transposase similar to the dna-binding domain of the transposase, the binding sites also have a bipartite structure in which the '- part of the binding site is recognized by the pai subdomain, whereas the '-sequences interact with the red subdomain of the transposase (figure a) (izsvák et al., ). specificity of dna-binding is predominantly determined by base-specific interactions mediated by the pai subdomain (izsvák et al., ). the pai subdomain also binds to the hdr motif within the left inverted repeat of sb, and mediates protein-protein interactions with other transposase subunits. thus, the pai subdomain is proposed to have at least three distinct functions: interaction with both the drs and the hdr motif, and transposase oligomerization. in cooperation with the main dna-binding domain, the grrr motif was shown to function as an at- hook, contributing to specific substrate recognition (izsvák et al., ). although part of the nls is included in the red subdomain, it does not appear to contribute to dna recognition. domain swapping experiments have shown that primary dna-binding is not sufficient to determine specificity of the transposition reaction. zebrafish tdr elements are closely related to sb, but are not mobilized by sb transposase. comparison of the transposase binding site sequences of sb and tdr elements revealed main differences in the '-half of the drs. this sequence is contacted by the red subdomain, indicating that the function of the red is to enforce specificity at a later step in transposition. substrate recognition of sb transposase is therefore sufficiently specific to prevent activation of transposons of closely related subfamilies. sleeping beauty the spacing between the drs is conserved in the ir/ dr group, and decreasing the distance between the drs has a negative effect on transposition (izsvák et al., ). the transposase does not bind the drs with equal affinity, it preferentially binds the internal recognition sequences (cui et al., ; zayed et al., ). perhaps due to the two-base-pair difference in length, the helical phasing of the outer binding sites make transposase binding unfavored at these sites. the significance of this unequal affinity in binding is discussed in the next section. synaptic complex assembly, and the role of the multiple binding sites for the transposase a uniform requirement among transposition reactions is the formation of a nucleoprotein complex, before the catalytic steps can take place. this very early step, synaptic complex assembly, is the process by which the two ends of the elements are paired and held together by transposase subunits. sleeping beauty transposition is controlled at the level of complex assembly (izsvák et al., ). the paired-like dna-binding domain forms tetramers in complex with transposase binding sites (izsvák et al., ). the necessary factors that are required for synaptic complex assembly of sb include the complete inverted repeats with four transposase binding sites, the hdr motif and tetramerization-competent transposase. these tetrameric complexes form only if all the four binding sites are present and they are in the in proper context. the hdr motif is important but not essential in transposition, and therefore can be viewed as a transpositional enhancer. our findings suggest that the transpositional enhancer and the pai subdomain of the transposase are stabilizing complexes formed by a transposase tetramer bound at the ir/dr. in contrast to mu transposase, where the two specificities of binding to the enhancer and to the recombination sites are encoded in two distinct domains (leung et al., ), the paired-like region of sb transposase combines these two functions in a single protein domain. the role of hmgb in sleeping beauty transposition: ordered assembly of synaptic complexes differential interactions between the transposon and host- encoded factors may result in limitation of host range. we have found that the high mobility group protein hmgb is required for efficient sleeping beauty transposition in mammalian cells (zayed et al., ). hmgb is an abundant, non-histone, nuclear protein associated with eukaryotic chromatin, and has the ability to bend dna (bustin, ). sb transposition was significantly reduced in hmgb -deficient mouse cells. this effect was complemented by expressing hmgb and hmgb , but not with the more distantly related hmga protein. overexpression of hmgb in wild-type cells enhanced transposition, indicating that hmgb is a limiting factor of transposition. hmgs have low affinity to standard, b-form dna, and interactor proteins need to guide them to certain sites (bustin, ). sb transposase was found to interact with hmgb in vivo, and to form a ternary complex with the transposase and transposon dna, suggesting that the transposase may actively recruit hmgb to transposon dna via protein-protein interactions. considering the significant drop of transposition activity in hmgb -deficient cells, the role of hmgb in transposition is a critical one. hmgb was proposed to promote communication between dna motifs within the transposon that are otherwise distant to each other, including the drs, the transpositional enhancer and the figure . a proposed model for the role of hmgb in sleeping beauty synaptic complex formation. sleeping beauty transposase (gray spheres) recruits hmgb (striped objects) to the transposon inverted repeats. first, hmgb stimulates specific binding of the transposase to the inner binding sites. once in contact with dna, hmgb bends the spacer regions between the drs, thereby assuring correct positioning of the outer sites for binding by the transposase. cleavage (scissors) proceeds only if complex formation is complete. the complex includes the four binding sites (black boxes), the hdr enhancer sequence (black circle) and a tetramer of the transposase. hmgb dr dr dr dr hdr tnpase ivics et al. two irs (figure ). however, as mentioned above, physical proximity of the drs is not sufficient for sb transposition; a highly specific configuration of functional dna elements within the inverted repeats has a critical importance. as mentioned earlier, sb transposase preferentially binds the inner drs within the transposon inverted repeats. it was also found that hmgb enhances transposase binding to both drs, but its effect is significantly more pronounced at the inner sites. it appears, therefore, that the order of events that take place during the very early steps of transposition is binding of transposase molecules first to the inner sites, and then to the outer sites. the pronounced effect of hmgb on binding of the transposase to the inner sites suggests that hmgb enforces ordered assembly of a catalytically active synaptic complex (figure ). indeed, interference with this sequence of events by replacing the outer transposase binding sites with the inner sites abolishes sb transposition (cui et al., ). this ordered assembly process probably controls that cleavage at the outer sites occurs only if all the previous requirements had been fulfilled. an assembly pathway similar to the one we propose for sleeping beauty has been described for bacteriophage λ (richet et al., ). the ir/dr-type organization of inverted repeats introduces a higher level regulation into the transposition process. the repeated transposase binding sites, their figure . the preferred insertion site of sleeping beauty is a bendable at-repeat. (a) consensus sequence of insertion sites. seqlogo analysis of five base pairs upstream and downstream of ta target sites. the y-axis represents the strength of the information, with bits being the maximum for a dna sequence. (b) bendability of sleeping beauty and tc target sites. dnase i digestion of radioactively labeled, -bp oligos containing either the -bp sb (vigdal et al., ) or -bp tc consensus insertion sequences (van luenen and plasterk, ), or two different -bp sequences with low predicted bendability was performed. the labeled bands in were quantitated with a phophorimager and graphed relative to each other. the uppercase letters indicate the core target sequence, while the lowercase letters indicate the identical flanking sequence. (!) sb consensus, (") tc consensus, (!) bad bender, (#) bad bender . b. c a c a t a t g t g g a t a t a t a t g g a a a a a a a a g t g a a a a a a a g a. sleeping beauty dissimilar affinity for the transposase, and the effect of hmgb to differentially enhance transposase binding to the inner sites are all important for a geometrically and timely orchestrated formation of synaptic complexes, which is a strict requirement for the subsequent catalytic steps of transposition. transposon excision all the dde recombinases catalyze similar chemical reactions (craig, ), which begin with a single-strand nick that generates a free '-oh group. to catalyze second strand cleavage, dde recombinases developed versatile strategies (turlan and chandler, ). the position of ’- cleavege of the second strand required for the liberation of the element occurs directly opposite to the ’-cleavage site in v(d)j recombination (gellert, ) and for the bacterial tn element (kennedy et al., ) (thereby generating blunt ended products), but it is staggered inwards the element by three nucleotides for sleeping beauty (luo et al., ) and by two nucleotides for the tc and tc elements (van luenen et al., ). thus, transposon excision leaves behind three-nucleotide-long ’-overhangs in sb transposition. dna repair of the broken dna ends generates transposon “footprints” that are therefore identical to the first or last three nucleotides of the transposon (luo et al., ). in v(d)j recombination, the single-strand nick is converted into a double-strand break by a transesterification reaction in which the free ’- oh attacks the opposite strand, thereby creating a hairpin intermediate (van gent et al., ; gellert, ). tn and tn transposons also transpose via a hairpin intermediate, with the difference that the hairpin is on the transposon and not on flanking dna (kennedy et al., ; bhasin et al., ). in contrast to v(d)j recombination, the excision sites do not have a hairpin structure in sb transposition (unpublished results). whether second-strand cleavage occurs by transesterification or by hydrolysis in sb transposition needs to be investigated. transposon integration: target site selection of sleeping beauty most transposable elements do not integrate randomly into target dna, and display some degree of specificity in target site utilization (craig, ). target selection may depend on primary dna sequence and chromatin structure, which can influence target site utilization by modulating the accessibility of dna. in some systems, including the bacterial transposon tn and the tc and tc transposons in caenorhabditis elegans, target site selection is primarily determined by the transposase itself (van luenen and plasterk, ; junop and haniford, ). sequences responsible for target site selection of tn and retroviruses have been mapped to the core catalytic domain of the transposase (or integrase) (katzman and sudol, ; junop and haniford, ), containing the dde signature. several members of the dde domain recombinase family integrate fairly randomly, yet not all possible sites are utilized within a genome with equal frequencies. despite the implication that the conserved catalytic domain is responsible for locating the target site, no common pattern of integration can be recognized on the sequence level. therefore, assuming that there might be common features of target selection in the dde family, it is an attractive hypothesis that structural properties of the target dna will be among them. because of the great potential of sb in genetic applications, determination of the factors affecting specificity of sb’s target site selection is of great importance. sleeping beauty displays a random pattern of integration in the human genome in order to analyze sb’s insertion profile on the genomic level, transposon insertions were generated in human hela cells using the in vivo transposition assay shown in figure b. insertion sites were identified and mapped on human chromosomes, using ncbi’s human genome blast service. although some chromosomes were hit more frequently than others, no clear preference was apparent for any chromosome, or for certain subchromosomal regions (vigdal et al., ). this observation indicates that most (if not all) chromosomes can serve as good targets for transposition. % of the transposition events occurred in transcribed regions. because about one third of the human genome is estimated to be transcribed (i. h. g. s. c., ), this frequency suggests no preference for or against insertion into genes. taken together, these results indicate a fairly random pattern of integration of sb elements in human chromosomes. sleeping beauty prefers a palindromic at-repeat for insertion sleeping beauty, like all other tc /mariner elements, integrates at ta dinucleotides (plasterk et al., ), which occur approximately once every basepairs, on average, in vertebrate genomes. we investigated whether all tas are equally good targets, or if other sequence determinants exist that influence sb’s target site selection. chromosomal sequences flanking integrated transposons were used to determine the dna sequence of a consensus target site. we found six bases directly surrounding the insertion site forming a short, palindromic at-repeat: atatatat (vigdal et al., ), in which the central underlined ta is the insertion site (figure a). both major steps of dna transposition, i. e. excision and integration, are catalyzed by the same catalytic domain of the transposase. we investigated whether excision and integration are under the same rules with respect to primary sequence of the dna that serves either as a target for transposition or as a donor site for element excision. if that were the case, an element that had transposed into the consensus target would excise more efficiently out of this site than from others. a collection of sb elements flanked by different base compositions were tested for their respective transpositional efficiencies. no dramatic effects on transposition were observed; the transposition efficiency ranged from a low of % to a high of % (vigdal et al., ). in general, homopolymeric stretches of nucleotides make poor excision substrates, whereas alternating purine and pyrimidine bases flanking the element are more efficient donor substrates. moreover, the preferred ivics et al. integration target sequence does not constitute an efficient donor site. apparently, sb is only moderately sensitive to the base composition of sequences immediately flanking the transposon at the excision step of transposition. structural properties of dna at sleeping beauty insertion sites a preference for inserting into a particular sequence raises the possibility that integration sites might have common structural features. we found three properties of dna that together define preferred sites for integration of sleeping beauty and other tc /mariner transposons. these are bendability (figure b), a-philicity and a symmetrical pattern of hydrogen bonding sites in the major groove of the target dna (vigdal et al., ). dna bending can lead to changes in the width and depth of the major and minor grooves, affecting a protein’s access to bases of the dna (brukner et al., ). a bendable structure may allow transposase and/or auxiliary host factors, to deform the bound dna into a spatial optimum for strand transfer. a- philicity represents the propensity of dna to form an a- dna like double helix (ivanov and minchenkova, ). a- dna has a wide and shallow minor groove that is believed to provide proteins easier access to form hydrogen bonds with bases within the dna helix. we have detected a - bp palindromic pattern of hydrogen bonding for both sleeping beauty and tc genomic insertions (vigdal et al., ). such palindromic pattern and the symmetry of the consensus target site sequence (figure a) together indicate that the target dna is recognized by a dimeric or multimeric form of the transposase, consistent with our earlier finding that sb transposase forms tetramers in solution (izsvák et al., ). alltogether the data indicate that, similar to some other transposable elements, target site selection of sb shows considerable specificity, and that it is primarily determined on the dna structural rather than on the sequence level. the results indicate that a combination of particular physical properties generate a spatial optimum of the dna for transposase interaction, and the ability of the transposase polypeptide to efficiently interact with such sequences specifies the sites where insertions occur. regulation of sleeping beauty transposition by intrinsic factors transposon movement is usually restricted in genomes to minimize the mutational damage inflicted on the host cell (hartl et al., ). consequently, naturally occuring transposons may not be the most active ones. transposon size is among the factors that can affect the efficiency of transposition. indeed, deleted, inactive transposon copies frequently accumulate in genomes, probably because the shorter versions transpose better. small size may not be an absolute requirement for mobilization, but it has been observed for different transposons, including sb, that longer elements tend to transpose less efficiently (lampe et al., ; izsvák et al., ). the efficiency of sleeping beauty transposition is higher when the donor transposon is present on a plasmid as opposed to a chromosome (luo et al., ). furthermore, reducing the outer distance between the two transposon ends in a plasmid-based vector enhances transposition (izsvák et al., ). however, when the transposon ends are less than bp apart from each other, transposition rates drop. these observations collectively indicate that physical distance between the transposon inverted repeats is an important determinant of the transposition process, perhaps by affecting synaptic complex assembly or stability. transposition of mariner elements was shown to be regulated by “overproduction inhibition”; an increase in the amount of transposase, either by increasing gene dosage or by increasing expression of a single gene, results in a decrease in transpositional activity (lohe and hartl, ). we have found in tissue culture experiments that the efficiency of sb transposition positively correlates with the number of available transposase and transposon molecules within a well-defined range (izsvák et al., ). however, high level sb transposase gene dosage in living mice resulted in repressed transpositional activity, suggesting the existence of a regulatory mechanism similar to overproduction inhibition (yant et al., ). future work will have to address the issue of regulation of sb transposition by transposase overexpression. links between dna transposition, retroviral integration and v(d)j recombination it has been proposed that there are mechanistic links between different recombination reactions such as the cut- and-paste transposition used by tc /mariner elements, bacteriophage mu transposition, and retroviral integration (craig, ). likewise, v(d)j recombination is a transposition-like reaction (van gent et al., ). the recombinases responsible for these reactions all contain dde domains (plasterk et al., ). the similarity between v(d)j recombination and transposition was further supported by the discovery that the rag proteins can mediate transposition of dna flanked by recombination signal sequences (agrawal et al., ; hiom et al., ), suggesting that the v(d)j recombination machinery evolved from an ancient rag transposon. the similarities are further emphasised in requirements for host factors. hmgb / were shown to enhance v(d)j recombination, by enhancing binding of the rag proteins to recombination signal sequences, and enforcing the cleavage to occur only at a defined combination of different recombination signals, which is termed the / rule (van gent et al., ; aidinis et al., ). hmga , that belongs to another family of hmg proteins, is required for retroviral integration (hindmarsh et al., ; li et al., ). in addition to the hmg proteins, the requirement for cellular proteins involved in double-strand dns break repair provides an addition to the several links between dna transposition, v(d)j recombination (gellert, ) and retroviral integration (daniel et al., ) that exist on evolutionary, structural and functional levels. sleeping beauty genetic applications sleeping beauty transposition in somatic tissues of the mouse in vitro induction of transposition and selection of cultured cells that harbor integrated transposons in their chromosomes can be useful when combined with embryonic stem cell technology (luo et al., ). however, there is considerable interest in technologies that allow the delivery and expression of genes in certain tissues or organs in vivo, for the correction of genetic diseases. evidence that the sb system can potentially be developed as a useful vector for gene therapy came from experiments in which the two components of the transposon system were administered into living mice by tail vein injection (table ) (yant et al., ). using this simple technology, about % of hepatocytes of the experimental animals expressed a foreign marker protein, β-galactosidase, from the lacz gene within the transposon vector. taking into account that the transposon vector cannot infect cells (thus active cellular uptake is not promoted), a % transformation efficiency is a significant result, because other integrating and infectious vectors such as retroviruses and adeno-associated virus vectors also transform hepatocytes in vivo with similar efficiencies. thus, sb can mediate efficient chromosomal integration of transgene constructs in vivo in a mammalian model system. for gene therapy, chromosomal integration of transgene constructs itself does not solve the problem, because in many cases the transferred gene has to be expressed for a prolonged period of time, and it has to express the gene product at a level that will have a therapeutic effect. the following four studies clearly demonstrated that the sb transposon can fulfill both requirements (table ). first, transgenic mice generated with an sb vector containing the human α- -antitrypsin (haat) cdna expressed haat in their blood for more than months (yant et al., ). second, transfer of an sb vector containing a human factor ix (fix) expression cassette resulted in partial correction of the bleeding disorder in haemophilic mice (yant et al., ), and sustained the production of biologically active fix at levels which would convert a severely affected patient with haemophilia b to one with a much milder phenotype. third, sb-mediated gene therapy in fumarylacetoacetate hydrolase (fah)-deficient mice has been shown to correct hereditary tyrosinemia type in % of the animals receiving a fah-expressing transposon construct and the transposase (montini et al., ). this latter study demonstrated an average transposon copy number of / diploid cellular genome in the liver, and a long-lasting transgene expression even after serial transplantation of hepatocytes. finally, the applicability of transposon- mediated gene transfer in human tissues was demonstrated in an ex vivo study, in which skin tissues of table . in vivo gene transfer in vertebrates in somatic tissues and in the germline using sleeping beauty. method of transfer vector target comment transferred gene organism aim ref. linearized dna mouse germ line oocyte injection mutagenesisneomycin . transposition/ sperm fischer et al., linearized plasmid+ mrna mouse germ line pronuclear injection germ line transgenesis gfp transposon array, transposition/ embryo, long term expr. dupuy et al., lacz α-antitrypsin factor ix hydrodynamic tail vein injection plasmid hepatocytemouse gene therapy yant et al., - % integration/ long term expr. tail vein injection/ infection adonovirus/ transposon hybrid hepatocytemouse lacz factor ix gene therapy yant et al., therapeutic level/ long term expr. fahhydrodynamic tail vein injection hepatocyteplasmid mouse gene therapy montini et al., % integration/ long term expr. linearized gene trap plasmid+ mrna mouse germ line pronuclear injection mutagenesisgfp dupuy et al., transposition/ sperm plasmid+ mrna zebrafish germ line microinjection germ line transgenesis gfp long term expr. dupuy et al., transfectionplasmid keratinocytehuman lamb gene therapy ortiz-urda et al., % integration/ therapeutic level/ long term expr. mouse germ line pronuclear injection mutagenesisgfp horie et al., transposition/ sperm linearized dna ivics et al. junctional epidermolysis bullosa patients were transfected with an sb vector expressing laminin (ortiz-urda et al., ). transformed cells were shown to regenerate healthy human skin with normal laminin expression, and thus to enable genetic correction of a life-threatening disease (ortiz-urda et al., ). together, the above studies have demonstrated the potential usefulness of sleeping beauty for the correction of human genetic diseases. one problem with respect to further applications is that the efficiency of in vivo gene transfer into many types of tissue with naked dna constructs is rather low, therefore the overall transformation rates with plasmid-borne sb vectors can be insufficient in clinical applications. a second problem is that the hydrodynamic injection method used in the above studies (injection of a large volume of dna solution into the bloodstream in a couple of seconds) is hardly applicable in humans. a potential solution to both problems was offered by engineering an adenovirus/sb hybrid vector (table ) (yant et al., ). adenovirus vectors are very efficient at infecting cells, but transgene expression from these vectors is transient due to the lack of stable genomic integration. repeated administration of adenovirus vectors can induce an immune response against viral proteins and the elimination of transduced cells. the adenovirus/sb hybrid combines the advantages of the two systems: high efficiency gene transfer and stable transgene integration and expression. sleeping beauty transposition in the vertebrate germline a requirement for the generation of stable transgenic stocks and for insertional inactivation of endogenous genes is that genetic changes are directed to the germline so that mutations will be passed on to the next generation. classical methods to express foreign genes in vertebrate animals rely on injection of nucleic acids into oocytes or fertilized eggs. these techniques are relatively simple, but because plasmid-borne genes are not equipped to promote chromosomal integration, their presence and expression is usually transient and mosaic, and very rarely results in figure . experimental strategies to induce transposition in the vertebrate germline. the figure shows a possible strategy for the zebrafish, but some of these methods can be adapted to other vertebrate species. the “jumpstarter” stock expresses the transposase in the male germline, and the “mutator” stock contains the mutagenizing transposon, preferably equipped with a gene trap marker. the two components are brought together in a hybrid after breeding of the two lines. transposition events will occur in the germline of males of f heterozygotes. these animals are crossed with wild-type females to segregate the insertion events in individuals of the f generation. f intercross yields f progeny, % of which is expected to contain the transposon insertion allele in a homozygous form. phenotypic changes can be observed in f . mutant genes can easily be cloned by different pcr methods making use of the inserted transposon as a unique sequence tag. sleeping beauty genomic integration. an improvement of germline transgenesis by sleeping beauty transposition has been demonstrated in zebrafish (nasevicius and ekker, ) and in the mouse (dupuy et al., ) (table ). the mouse experiments were done by pronuclear microinjection of a gfp-marked transposon together with sb transposase mrna synthesized in vitro (dupuy et al., ). a transgenic frequency of % was established (as opposed to % in the absence of transposase) (table ). integrated transposons undergo germline transmission, and are expressed in the offspring. these results demonstrate the usefulness of transposition for the generation of stable transgenic lines in vertebrate models. breeding of “jumpstarter” and “mutator” stocks to induce transposition in the germline of the hybrid this is most likely the preferred method for generating large numbers of transposon insertions for insertional mutagenesis, a method that cannot be applied for retrovirus vectors. in this experimental setup, two transgenic lines need to be generated first; a “jumpstarter” stock expressing the transposase in the male germline, and a “mutator” stock containing the transposon to be mobilized (figure ). these two stocks are crossed to bring the two components of the transposon system together, and transposition is expected to occur in the sperm cells of males of the heterozygous hybrids. such males would be crossed to wild type females to segregate the different insertion events in the genomes of their sperm cells into separate animals (figure ). recent evidence suggests that such a scheme might be useful for generating insertional mutations in vertebrate model systems (fischer et al., ). two separate transgenic mouse lines have been established: one expressing the sb transposase from the protamine promoter which is active during spermiogenesis, and the other containing an integrated neo-merked sb element. in % of the offspring of double-transgenic males the transposon jumped to different genomic locations, and transposon insertions are stably transmitted in the absence of the transposase (fischer et al., ) (table ). subsequent to this study, two other papers describing a similar experimental design and even more encouraging results were published (dupuy et al., ; horie et al., ). both studies employed a ubiquitous promoter to drive the expression of the sleeping beauty transposase in transgenic mice, and a multicopy array of transposons as donors for transposition. horie et al. ( ) have found up to % of the progeny of a double-transgenic male to contain transposition events, and estimated the frequency of germline transposition to be about one event per gamete, whereas dupuy et al. ( ) estimate that, on average, their double-transgenic males carry about two new transposon insertions per sperm cell. although further studies are required to establish a protocol for inducing large numbers of transposon insertions in the mouse germ line, it appears that promoter choice and a chromosomal pool of transposons with a sufficiently large number of elements available for mobilization will be among the important parameters. what frequency of transposition is required for optimal mutagenesis? insertional mutagenesis is less efficient than chemical mutagenesis. however, on average, the phenotypic effect of a transposon insertion is more dramatic than that of a single nucleotide substitution. although relatively random insertion of transposon vectors can be a clear advantage for gene identification through insertional mutagenesis, a limiting factor can be the overall frequency of transposition. a critical parameter contributing to the success of insertional mutagenesis with transposable elements will be if multiple transposon insertions per gamete can be generated. the relative inefficiency of gene inactivation with insertional mutagens can be counterbalanced by the fecundity of model species such as fish or frogs, where several thousand embryos can be generated in a single mating. preferably, the transposon would contain a gene trap construct to allow for selection of transposon insertions into genes. in the mutator stock, the gene trap must not be expressed. offsping of double-transgenic males can be examined for expression of the gene trap marker such as the green fluorescent protein (gfp), which is indicative of transposition of the marker elements into expressed genes. usually, mutations can only be observed when products of both copies of a gene are inactivated. by bringing the insertions identified in the founder animals to homozygosity, animals that contain two mutant copies of the affected gene can be generated. the spatial/temporal expression of the transposon marker and possible phenotypic effects (mutations) can be examined over the course of embryonic development, and the affected tissues/organs/ developmental pathways can be colocalized with the marker. acknowledgements we thank d. fiedler, e. stüwe and a. katzer for their technical assistance. work in this laboratory is supported by eu grant qlg -ct- - 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. vos, j.c., i. de baere, and r.h. plasterk. . transposase is the only nematode protein required for in vitro transposition of tc . genes dev. : - . vos, j.c. and r.h. plasterk. . tc transposase of caenorhabditis elegans is an endonuclease with a bipartite dna binding domain. embo j. : - . yant, s.r., a. ehrhardt, j.g. mikkelsen, l. meuse, t. pham, and m.a. kay. . transposition from a gutless adeno- transposon vector stabilizes transgene expression in vivo. nat biotechnol : - . yant, s.r., l. meuse, w. chiu, z. ivics, z. izsvák, and m.a. kay. . somatic integration and long-term transgene expression in normal and haemophilic mice using a dna transposon system. nat. genet. : - . zayed, h., izsvák, z., khare, d., heinemann, u. and z. ivics. . the dna-bending protein hmgb is a cellular cofactor of sleeping beauty transposition. nucleic acids res. : - . • maldi-tof mass spectrometry in microbiology edited by: m kostrzewa, s schubert ( ) www.caister.com/malditof • aspergillus and penicillium in the post-genomic era edited by: rp vries, ib gelber, mr andersen ( ) www.caister.com/aspergillus • the bacteriocins: current knowledge and future prospects edited by: rl dorit, sm roy, ma riley ( ) www.caister.com/bacteriocins • omics in plant disease resistance edited by: v bhadauria ( ) www.caister.com/opdr • acidophiles: life in extremely acidic environments edited by: r quatrini, db johnson ( ) www.caister.com/acidophiles • climate change and microbial ecology: current research and future trends edited by: j marxsen ( ) www.caister.com/climate • biofilms in bioremediation: current research and emerging technologies edited by: g lear ( ) www.caister.com/biorem • microalgae: current research and applications edited by: mn tsaloglou ( ) www.caister.com/microalgae • gas plasma sterilization in microbiology: theory, applications, pitfalls and new perspectives edited by: h shintani, a sakudo ( ) www.caister.com/gasplasma • virus evolution: current research and future directions edited by: sc weaver, m denison, m roossinck, et al. 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( ) www.caister.com/bacteria-plant • aeromonas edited by: j graf ( ) www.caister.com/aeromonas • antibiotics: current innovations and future trends edited by: s sánchez, al demain ( ) www.caister.com/antibiotics • leishmania: current biology and control edited by: s adak, r datta ( ) www.caister.com/leish • acanthamoeba: biology and pathogenesis ( nd edition) author: na khan ( ) www.caister.com/acanthamoeba • microarrays: current technology, innovations and applications edited by: z he ( ) www.caister.com/microarrays • metagenomics of the microbial nitrogen cycle: theory, methods and applications edited by: d marco ( ) www.caister.com/n caister academic press is a leading academic publisher of advanced texts in microbiology, molecular biology and medical research. full details of all our publications at caister.com further reading order from caister.com/order doi: . /rspb. . proc. r. soc. b ( ) , – doi: . /rspb. . did the perils of abdominal obesity affect depiction of feminine beauty in the sixteenth to eighteenth century british literature? exploring the health and beauty link devendra singh ,*, peter renn and adrian singh the university of texas at austin, university station a , austin, tx - , usa harvard law school, cambridge, ma , usa published online january * autho received accepted ‘good gene’ mate selection theory proposes that all individuals share evolved mental mechanisms that identify specific parts of a woman’s body as indicators of fertility and health. depiction of feminine beauty, across time and culture, should therefore emphasize the physical traits indicative of health and fertility. abdominal obesity, as measured by waist size, is reliably linked to decreased oestrogen, reduced fecundity and increased risk for major diseases. systematic searches of british literature across the sixteenth, seventeenth and eighteenth centuries reveal that a narrow waist is consistently described as beautiful. works in ancient indian and chinese literature similarly associate feminine attractiveness with a narrow waist. even without the benefit of modern medical knowledge, both british and asian writers knew intuitively the biological link between health and beauty. keywords: attractiveness; abdominal obesity; fecundity; health; literature; waist . introduction health is beauty, and the most perfect health is the most perfect beauty. british author william shenstone ( – ) writers and artists have devoted immense time and effort to depicting feminine beauty (thiessen & umezawa ). why does feminine beauty have such a strong, persistent and universal appeal? evolutionary psycho- logical theorists propose that beauty reliably advertises a woman’s good health and fertility (symons ). accordingly, laymen and artists alike should share evolved mental mechanisms that associate specific parts of a woman’s body with fertility and health, although not necessarily in a conscious fashion. for example, we now know that abdominal obesity, as measured by waist size, is reliably linked to decreased oestrogen, reduced fecundity and increased risk for major diseases (kissebah & krakower ; yusuf et al. ). collectively, these physical cues such as the waist size form the basis for an evolved standard of beauty (grammer et al. ). depictions of feminine beauty should therefore also emphasize those physical features that are indicative of good health and fertility. literature provides one window into the architecture of the human mind by revealing possible universal cogni- tions, motivations and emotions (carroll ). it also provides information that would be difficult to obtain by any other means. for instance, it offers one means by which to test whether writers in pre-modern europe— prior to mass media and modern medical knowledge— described a narrow waist as a component of feminine r for correspondence (singh@psy.utexas.edu). november december beauty. the present study examined the sixteenth to eighteenth century british literature in order to determine how often writers described a narrow waist as beautiful. the study also examined whether romantic literature from india and china described a narrow waist as beautiful. (a) narrow waist: an indicator of health and fertility in the past years, clinical and epidemiological research has shown that the anatomical location of body fat affects risk factors for various diseases. abdominal obesity, as measured by waist size and a ratio of waist to hip circumference (waist-to-hip ratio), is a key predictor of cardiovascular disorders, diabetes ii, various cancers (breast, ovarian and endometrial) and gall bladder disease (singh ). moreover, changes in circulating oestrogen levels affect waist size ( jasienska et al. ); after puberty, as oestrogen levels increase, the waist narrows. con- versely, as women age, the production of oestrogen decreases and the waist enlarges. the current health guideline is that a large waist size ( cm or greater) in women should be used as a marker of risk for various diseases, independent of overall body weight (han et al. ; national institute of health ). waist size is the only scientifically documented visible body part that conveys reliable information about reproductive age, sex hormone profile and risk for major diseases. if universal mental mechanisms equating fertility and health with feminine beauty have indeed evolved, then artists and writers in past and present societies should describe narrow waists as beautiful. although local conditions and cultural practices undoubtedly shape metaphors, similes and other literary devices, the current evolutionary hypothesis predicts that imaginative and this journal is q the royal society table . frequency distribution of reference to body parts in romantic writings of british authors. (the numbers in parentheses denote the frequency of physical description (shape and/or size) of the body part.) search term sixteenth century ( – ) seventeenth century ( – ) eighteenth century ( – ) no. of entries no. of romantic references no. of entries no. of romantic references no. of entries no. of romantic references waist ( ) ( ) ( ) breasts ( ) ( ) buttocks ( ) hips ( ) ( ) ( ) thighs ( ) ( ) legs ( ) ( ) plump slim d. singh et al. literature and health creative musings should emphasize the waist as a marker of feminine beauty. (b) narrow waist: a marker of beauty consider some of the specifications of feminine beauty as described by: proc. r her skin, and teeth, must be cleare, bright, and neat. large brests, large hips, large space betweene the browes, a narrow mouth, small waste. british poet sir john harington ( ) since the waist does not intuitively appear to be a sexually attractive body part (like the breasts or hips), it is strange to describe a narrow waist as an essential bodily feature of a beautiful woman. despite a few studies reporting that some present tribes do not find a small waist attractive (yu & shepard ; marlowe & wetsman ), a small waist seems to have a near universal historical appeal. could the poet ‘know’, without being consciously aware, that such a description would appeal to the readership due to a shared meaning of physical attractiveness? the oldest reference linking beauty and small waist size is the epithet of queen nefertari, the favourite wife of ramses ii, second millennium b.c.e. ‘.the buttocks are full, but her waist is narrow.the one for who[m] the sun shines.’ . study : beauty and the narrow waist to test whether a narrow waist has historically been viewed as attractive, we examined the british literature (prose, poetry and drama) between the sixteenth and the eight- eenth centuries. the literature spanning these centuries is readily accessible on the website literature online (lion; http://lion.chadwyck.com\). this database contains over british and american works of fiction, prose and drama from the sixteenth ( – ), seventeenth ( – ) and eighteenth ( – ) centuries. while lion is not necessarily exhaustive, it represents the largest collection of published british works. (a) method we searched the literature for any reference to a female waist and examined every passage that contained each such reference. as a control, we also searched for the words breast, hip, buttocks (bum), leg, thighs, slim and plump and compared how often the authors referred to . soc. b ( ) these characteristics as attractive. for all terms, we searched for alternate spellings (e.g. waste, waiste) and plurals (e.g. breasts) and created an aggregate number of hits for each search item. two independent raters other than the authors examined those passages containing target items to judge whether the reference was romantic or non-romantic (e.g. ‘her hair came down to her waist’ versus ‘longing to hold her lovely waist’). there was high interrater reliability: out of entries, raters disagreed only in cases. the probability that the raters were operating independently or randomly in their judgment (controlling for high rate of ‘romantic’ rating in both raters) is exceptionally low ( p! ! k ). after excluding the entries that the raters disagreed upon, the remaining romantic entries were divided into two categories: (i) those which have no reference to size or shape (e.g. ‘better are thy breasts than wine’; ‘beholden to her lovely waist’) and (ii) those in which either the shape or size was actually described (e.g. pretty, round, heavy breasts; slim or tapered waist) or defined by analogy (e.g. ‘thy breasts are like ripe pomegranates’; ‘whose waste is little as a wand’). the raters did not disagree on any entries into these categories. (b) result and discussion as evident in table , for every century, three body parts— breasts, waist and thighs—are more often referred to as beautiful than other body parts. moreover, waist size was always described as narrow or small; there were romantic descriptions of waist in these three centuries, and every one of them referred to narrow waist. in contrast, while breasts had the most romantic references ( entries), there were only instances describing breast shape or size. there was only one reference for large breasts and three for small breasts, whereas descrip- tions referred to the roundness of the breasts (figure ). apparently, it is the shape (roundness—a sign of youthfulness; grammer et al. ), rather than the size, of breasts that is judged to be beautiful. furthermore, there were romantic references to various body sizes— references to plump women and references to slim women—but none of these references describe an enlarged waist. there were four references admiring slim women. thus, reference to body size is more variable, but there are no instances of thicker waists being described as attractive. the tendency among writers to consistently http://lion.chadwyck.com\ table . frequency distribution of reference to body part in romantic writings of indian and chinese authors. (the numbers in parentheses denote the frequency of physical description (shape and/or size) of the body part.) search item india china first to third century fourth to sixth century no. of entries no. of romantic references no. of entries no. of romantic references waist ( ) ( ) breasts ( ) buttocks ( ) hips ( ) thighs ( ) legs plump slim – % % % % small/narrow small round large waist (n = ) breast (n = ) large/wide fr eq ue nc y – % figure . total number of references summed across sixteenth to eighteenth century describing the shape/size of waist and breasts. literature and health d. singh et al. describe narrow waists as beautiful suggests that the narrow waist has a universal and timeless appeal. . study : allure of narrow waist in non-western cultures if evolved psychological mechanisms equate health and beauty, one would expect these links to be universally shared. selection of literature from non-western cultures poses the problem of cultural diffusion; one could argue that exposure to western culture influences the literary content and style of non-western cultures. additionally, local cultures and religious practices in many non-western societies may not sanction description of various female body parts. we therefore asked professors of asian literature in two universities to nominate ancient erotic/romantic poetry describing beautiful women. experts suggested two ancient indian epics, mahabharata and ramayana (first to third century), and chinese sixth dynastic palace poetry (fourth to sixth century). (a) method following the procedure used in the first study, references to body parts were rated by two independent raters to determine whether the entry was romantic or non- romantic, and if romantic, whether it specified the shape and size of the body part. there was no disagreement on the classifications of any entries between the two raters. (b) results table shows the number of entries, romantic references and references which described the size/shape of the body part for the literature from india and china. indian literature contained the largest number of shape descrip- tions of the waist, followed by the hips, breasts and thighs. all the references that described waist shape/size referred to slender waist. hips and breasts were described as full and round and thighs as tapering. in chinese literature, there were shape references, and in every instance, the waist was defined as narrow or slender. we did not find any romantic references to the breasts, hips, buttocks or thighs. neither indian nor chinese writers mentioned plumpness as beautiful, although a slim body was mentioned as attractive in a few indian and chinese references (two and four, respectively). proc. r. soc. b ( ) (c) discussion the difference between ancient indian and chinese descriptions of female body parts is probably due to differences in cultural practices. the ancient indian artists created sculptures showing nude female bodies (some- times in sexual acts) and literature which contained detailed descriptions of body parts and sexual acts. ancient chinese tradition, however, apparently did not sanction such depictions in literature. it is remarkable that in spite of these cultural differences, both indian and chinese writers used a slender waist to convey ideal feminine beauty. consider, for instance, the description by chinese writer xu ling ( – ) ‘beautiful women.in the palace of chu, there were none who did not admire their slender waist; the fair woman of wei’ (quoted by wu , p. ). similarly, the indian epic mahabharata contains the following description: ‘.accept this slender- waisted damsel for thy spouse’ (ganguli – ). the probability that two ancient cultures opted to stress a slender waist as one of the hallmarks of feminine beauty by sheer chance is exceedingly miniscule. . conclusion: literature—a window into human nature the validity of the darwinian notion that the cognitive structures we currently possess are adaptations to problems encountered in our phylogenetic past depends on demonstrating that (i) core cognitions are shared cross- culturally in spite of variations caused by ecological differences and (ii) such cross-cultural consensus is not due to shared, but novel environment. for cross- generational consensus, literature and art comprise a rich data source. the cognitions and motivation of our ancestors are enshrined in art and literature. recently, some scholars, known as ‘literary darwinians’, have explored classical literature and tales from diverse societies to examine whether darwinian concepts occur universally (gottschall & wilson ). references to beautiful women abound throughout human history and across cultures. ancient greek epics (helen of troy), persian and chinese poetry, indian classics, mythology and even popular or folk stories glorify feminine beauty. d. singh et al. literature and health feminine beauty is multifaceted, and poets and writers in different eras and cultures have freedom to describe feminine beauty. the common historical assumption in the social sciences has been that the standards of beauty are arbitrary, solely culturally determined and in the eye of the beholder. the finding that the writers describe a small waist as beautiful suggests instead that this body part—a known marker of health and fertility—is a core feature of feminine beauty that transcends ethnic morphological differences and cultures. our study suggests that in spite of variation in the description of beauty, the marker of health and fertility—a small waist—has always been an invariant symbol of feminine beauty. we wish to thank alejandro tyler, jason roth, tim riley, deepa gupta, aresh ebrahimi and lu shen for their help in collecting data, to tim chen and fusheng wu for their help with chinese literature and to drew bailey for his help in statistical analysis. references carroll, j. literary darwinism: evolution, human nature, and literature. new york, ny: routlege. clinical guideline in the identification, evolution, and treatment of overweight and obesity in adults. the evidence report. national institute of health. obes. res. (suppl. ), s – s. ganguli, k. m. – english translation of mahabhar- ata of krishna dwaipayana e-book. http://www.guten- berg.org/dirs/etext / mkdw .txt. date retrieved: september , . gottschall, j. & wilson, d. s. (eds) the literary animal. evanston, il: northwestern university press. proc. r. soc. b ( ) grammer, k., fink, b., moller, a. p. & thornhill, r. darwinian aesthetics: sexual selection and the biology of beauty. biol. rev. , – . (doi: . / s ) han, t. s., van leer, e. h., seidell, j. c. & lean, m. e. j. waist circumference action levels predict cardiovas- cular risk factors: prevalence study in a random sample. br. med. j. , – . jasienska, g., zimokiewicz, a., ellison, p. t., lipson, s. f. & thune, i. large breasts and narrow waist indicate high reproductive potential in women. proc. r. soc. b , – . (doi: . /rspb. . ) kissebah, a. h. & krakower, g. r. regional adiposity and mortality. physiol. rev. , – . marlowe, f. & wetsman, a. preferred waist-to-hip ratio and ecology. pres. indiv. differ. , – . (doi: . / s - ( ) - ) singh, d. female mate value at a glance: relationship of waist-to-hip ratio to health, fecundity, and attractiveness. neuroendocrinol. lett. (suppl. ), – . symons, d. the evolution of human sexuality. new york, ny: oxford university press. thiessen, d. & umezawa, y. the sociobiology of everyday life: a new look at a very old novel. hum. nat. , – . wu, f. the poetics of decadence: chinese poetry of southern dynastic and late tang period. albany, ny: state university of new york press. yu, d. & shepard, g. h. is beauty in the eye of the beholder? nature , – . (doi: . / ) yusuf, s., hawken, s. & ounpun, s. obesity and risk of myocardial infraction in participants from countries: a case-control study. lancet , – . (doi: . /s - ( ) - ) http://www.gutenberg.org/dirs/etext / mkdw .txt http://www.gutenberg.org/dirs/etext / mkdw .txt http://dx.doi.org/doi: . /s http://dx.doi.org/doi: . /s http://dx.doi.org/doi: . /rspb. . http://dx.doi.org/doi: . /s - ( ) - http://dx.doi.org/doi: . /s - ( ) - http://dx.doi.org/doi: . / http://dx.doi.org/doi: . /s - ( ) - did the perils of abdominal obesity affect depiction of feminine beauty in the sixteenth to eighteenth century british literature? exploring the health and beauty link introduction narrow waist: an indicator of health and fertility narrow waist: a marker of beauty study : beauty and the narrow waist method result and discussion study : allure of narrow waist in non-western cultures method results discussion conclusion: literature-a window into human nature we wish to thank alejandro tyler, jason roth, tim riley, deepa gupta, aresh ebrahimi and lu shen for their help in collecting data, to tim chen and fusheng wu for their help with chinese literature and to drew bailey for his help in statistical analysis. references [pdf] cp violation with beautiful baryons | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /bf corpus id: cp violation with beautiful baryons @article{dunietz cpvw, title={cp violation with beautiful baryons}, author={i. dunietz}, journal={zeitschrift f{\"u}r physik c particles and fields}, year={ }, volume={ }, pages={ - } } i. dunietz published physics zeitschrift für physik c particles and fields abstractcp violation can be studied in modes of charmed or bottom baryons when a decay process is compared with its charge-conjugated partner. it can show up as a rate asymmetry and in a study of other decay parameters. neither tagging nor time-dependences are required to observecp violation with modes of baryons, in contrast to the conventionalb modes. numerous modes of bottom baryons have the potential to show largecp-violating effects within the standard model. those effects can be… expand view on springer cds.cern.ch save to library create alert cite launch research feed share this paper citationsbackground citations methods citations view all figures and tables from this paper figure table table figure figure table figure table figure table table table figure figure view all figures & tables citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency nonleptonic weak decays of bottom baryons h. cheng physics pdf save alert research feed cp violation and the ckm matrix: assessing the impact of the asymmetric b factories j. charles, a. hoecker, + authors l. roos physics pdf save alert research feed cp violation in b→d+(cc without tagging i. dunietz physics save alert research feed nonleptonic beauty baryon decays and c p asymmetries based on an s u ( ) -flavor analysis s. roy, r. sinha, n. g. deshpande physics pdf save alert research feed studies of beauty baryons decaying to d pπ − and d pk − the lhcb collaboration a. poluektov pdf view excerpt, cites methods save alert research feed beauty baryon nonleptonic decays into decuplet baryons and $cp$ -asymmetries based on an $su( )$ -flavor analysis s. roy, r. sinha, n.g.deshpande physics pdf save alert research feed study of the kinematic dependences of Λb production in pp collisions and a measurement of the Λb → Λc+π− branching fraction r. aaij, b. adeva, + authors s. ricciardi physics pdf view excerpt, cites background save alert research feed cp violation in the k-meson system k. mcdonald physics pdf save alert research feed atlas: helicity analyses in beauty hadron decays m. smizanska physics save alert research feed extracting the unitarity angle γ in bs→d h ,d¯ h decays c. chua physics pdf save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency exclusive non-leptonic decays ofd-,ds- andb-mesons m. bauer, b. stech, m. wirbel physics save alert research feed cp violation using non-cp eigenstate decays of neutral b mesons r. aleksan, i. dunietz, b. kayser, f. diberder physics pdf save alert research feed the question of {cp} noninvariance - as seen through the eyes of neutral beauty i. bigi, a. sanda, n. uraltsev, v. khoze physics pdf save alert research feed first observation of the beauty baryon Λb in the decay channel Λb→j/ψΛ at the cern proton-antiproton collider c. albajar, m. albrow, + authors p. zotto physics pdf save alert research feed cp violation with self-tagging bd modes i. dunietz physics pdf save alert research feed cp violation in the renormalizable theory of weak interaction m. kobayashi, t. maskawa physics , pdf save alert research feed final-state interactions and cp violation in weak decays. wolfenstein physics, medicine physical review. d, particles and fields pdf save alert research feed standard-model predictions for cp violation in b -meson decay. dib, dunietz, gilman, nir physics, medicine physical review. d, particles and fields pdf save alert research feed branching ratios and cp-violating asymmetries in exclusive charged b-meson decays h. simma, d. wyler physics save alert research feed cp violation in radiative b decays j. m. soares physics save alert research feed ... ... related papers abstract figures and tables citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - 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( ) aesthetic value: beauty, ugliness and incoherence. philosophy, ( ). pp. - . issn - eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ reuse see attached takedown if you consider content in white rose research online to be in breach of uk law, please notify us by emailing eprints@whiterose.ac.uk including the url of the record and the reason for the withdrawal request. mailto:eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ promoting access to white rose research papers white rose research online universities of leeds, sheffield and york http://eprints.whiterose.ac.uk/ white rose research online url for this paper: http://eprints.whiterose.ac.uk/ / published paper kieran, m. ( ) aesthetic value: beauty, ugliness and incoherence, philosophy, volume ( ), - . eprints@whiterose.ac.uk aesthetic value: beauty, ugliness and incoherence m a t t h e w k i e r a n i: beauty and aesthetic value from plato through aquinas to kant and beyond beauty has tradi- tionally been considered the paradigmatic aesthetic quality. t h u s , quite naturally following socrates' strategy in the meno, we are tempted to generalize from our analysis of the nature and value of beauty, a particular aesthetic value, to an account of aesthetic value generally. when we look at that which is beautiful, the object gives rise to a certain kind of pleasure within us. t h u s aesthetic value is characterized in terms of that which affords us pleasure. of course, the relation cannot be merely instrumental. many activities may lead to consequent pleasures that we would not consider to be aes- thetic in any way. for example, playing tennis, going swimming or finishing a book. rather it is in the very contemplation of the object itself that we derive pleasure. as kant puts it: ive dwell on the contemplation of the beautiful because this con- templation strengthens and reproduces itself. t h e case is analo- gous (but analogous only) to the way we linger on a charm in the representation of an object which keeps arresting the attention, the mind all the while remaining passive.' t h u s contemporary philosophers have, following this tradition, defined aesthetic value in terms of our delighting in and savouring an object with pleasure.* an object is of intrinsic aesthetic value if it appropriately gives rise to pleasure in our contemplation of it. of course background knowledge of particular art movements, cate- gories or artistic intentions may be required to perceive an artwork appropriately. nonetheless, given the relevant understanding, it is ' immanuel k a n t , the critique of judgement, trans. j . c . meredith, (oxford 'niversity press, ), book i , section , p. . * see, for example, kendall walton, ' h o w marvellous! toward a t h e o r y of aesthetic value', journal of aesthetics and art criticism, vol. , no. , pp. - , malcolm budd, values of art, (london: penguin, ), pp. - , and jerrold levinson, 'pleasure, aesthetic' in david cooper ( e d . ) , a compatriot to aesthetics (oxford: blackwells, ), pp. - . philosophy matthew kieran in attending to and savouring u h a t is presented to us that we are afforded pleasure. of course, we may delight in many things that are presented to us which are not beautiful, such as the comic and the tragic, which we still wish to characterize as aesthetic. \ve cannot, of course, say they are aesthetic by virtue of the pleasure deriving from their beaut): for often what is tragic or comic is far from beautiful at all. hence if we are to grasp the essence of aesthetic value, we need a more general characterization. t h e standard move is to use the same form of explanation, where beauty mas taken as the paradigmatic aes- t h e t ~ c qualit?; to derive a general account of aesthetic value. t h e classic account given by beardsley locates aesthetic value, in quali- ties which vary from the beautiful to the comic or tragic, in the for- mal unit?; complexity and intensity of an object's formal and cog- nitive features.' \l.'hat unites all the various aesthetic qualities is the peculiar delight me take in the development of a theme, the elegance of the representation and so on. t h u s , it is thought, lve can use the characterization of aesthetic value to generate general principles of aesthetic evaluation. t h e core thought is that what we take delight in is itself delightful, in terms of unit?; harmon); coherent structure and complex development. : counter-examples however, this standard picture of aesthetic value seems far from adequate if we consider the folloxving kinds of cases. firstly, con- sider the case of punk. i take ~t that the whole point of punk, incor- porating both music and fashion, was to achieve both maximal ugli- ness and incoherence. t h e point of putting studs or safety pins through noses, dying scruff\; unkempt hair in g a r ~ s h colours, dress- ing u p in black bin bags, tartan zipped trousers and slashed t-shirts was precisely to achieve an incoherent, ugly look. t h i s was, in part, in contra-distinction to the highly stylized, slick and formal empha- sis on elegance that was taken to be predominant at the time. similarly the use of discordance, guitar feedback and yelling stood in stark contrast to the overblom n, overproduced formalit~es of con- cept rock and the smooth, polished rhythms and harmonies of disco. if one searches for the qualities of coherence or complexitj- in punk music one is not onll- likely to be disappointed but be in for ' ilionroe beardsley, aesthetrcs ( y e n t o r k : h a r c o u r t , brace a n d fl'orld, ), s e c t ~ o n , pp. - , a n d aionroe b e a r d s l e ~ , ' o n t h e g e n e r a l ~ t y of c r ~ t i c a l reasons', journal of philosophy, yol. lix, s o . , , pp. - . aesthetic value: beauty, ugliness and incoherence a very painful and unpleasant experience. which is why many peo- ple find it unintelligible that anyone should like punk at all. but if someone looks for and savours the sheer brute ugliness and inco- herence of it all, then they will derive pleasure from it. an analo- gous example in the case of classical music is the work of composers like stockhausen and john cage. t h e point of their music lies in contra-distinction to the setting u p and development of themes and harmonies that typified classical music heretofore. i t is also important to note that the positive evaluation of quali- ties such as ugliness and incoherence are not confined to the sphere of music or the transitory zeitgeist of fashion. i n visual art there is a long tradition of the rendering of grotesques, both real and imag- inary; one only has to think of late michelangelo, the late renaissance generally, francis bacon or andreas serrano. i t seems that we do derive a peculiar delight from the portrayal of distorted physiognomies or the rendering of grotesques. indeed, many art- works not only involve distinctly repulsive emotions, thoughts and depictions but use repellant materials as well. so even though an artwork may be constituted from repugnant materials, depict per- verse scenes or people, we may be afforded pleasure by attending to them rather than being repelled by them. one reason for this might be that alluded to by john constable: t h e r e is nothing ugly; i never saw an ugly thing in my life: for let the form of an object be what it may,-light, shade, and perspec- tive will always make it beautiful.' subject matter we would ordinarily find disgusting might afford pleasure if it is artistically manipulated in a certain way and we are constrained to regard it in a certain light. t h e peculiar orange medium bathing the crucifix in andreas serrano's piss christ con- stitutes a peculiarly pleasing, luminous light if looked at indepen- dently of the material's associations. t h u s the contribution of materials we would normally consider repugnant, such as various bodily fluids, may constitute valuable features of an artwork. but it is crucial to recognize that the appeal of such works lies not merely in the way the subjects are rendered but in the very grotes- query of the image itself. t h e high degree of unpleasantness involved often seems central to some artworks. we miss the entire point of serrano's piss christ if we fail to realize what the medium is. t h e very fact that the urine the crucifix is bathed in is high- lighted in the work's title ought to indicate its central relevance to the work. if we just looked at the luminous, aesthetically appealing ' john constable as quoted in c. r. leslie, ivlemoirs of the life of john constable ( ), chapter . matthew kieran liquid bathing the crucifix without knowledge of its constituent material, we would have missed the point of the work. for the work's point lies in the juxtaposition of the meaning and associa- tions of the medium used and the crucifix suspended in it. consider, in a similar vein, the buiiuel and dali film u n chien andalou where several different parts are played by the same actor and actress, where the landscape outside the window changes arbitrarily from landscape one minute to cityscape the next and where the juxtaposition of surreal images and stark edits all con- tribute to the film's maximal incoherence. t h e very point of the film is its lack of coherence, its opaqueness to attempts to analyse and make sense of it, whilst textured images such as the grotesque slitting of a donkey's eyeball continue to haunt the mind. t h e point of these examples is that we, or at least some of us, seem to value in art images or music which are assumed to fall out- side the sphere of aesthetic value because they are ugly, grotesque or incoherent and that is their very point. t r u e , aesthetic theorists such as beardsley may deny such works have any aesthetic value at all. but then this severely weakens the force of their claim to ha\,e captured the notion of aesthetic value, since many people clearly do value such qualities in artworks and, moreover, they are valued as such in many acclaimed masterpieces. t h u s , lve might be tempted to conclude, the typical picture of aesthetic value must be inade- quate. : cognitive value o n e possible reply to such an objection is to claim that the examples cited are not really counter examples at all. for we must be careful to separate out cognitive value from aesthetic value. it seems clear that in art we value many different qualities, from the expressive to the cognitive, and not merely the aesthetic. it is crucial that we rec- ognize that artistic and aesthetic value are not co-extensive. a game of football or chess may have great aesthetic value, due to the sheer artistry and elegance of the players, yet we would hesitate to call such things artworks. conversely, most conceptual art, dada art- works or the music of john cage and stockhausen may almost entirely lack aesthetic value and yet clearly be considered artworks due to their expressive nature or cognitive content. i n these cases even if the work does possess aesthetic value, this seems almost entirely incidental to the reasons we attend to and value them as art- works. t h u s , it may be claimed, what xve value in the counter-examples aesthetic value: beauty, ugliness and incoherence cited are not any putative aesthetic qualities but rather the cognitive attitudes represented or explored through them. for example, punk took off not merely as a reaction against the slick, stylized, heavily produced music of the time but as, in essence, an anti-establishment cult which aimed to tear down the supposed walls of snobbery, materialism and bourgeois aspirations. t h i s is why, it might be said, many people do not and cannot enjoy punk music. for only if one takes punk as expressive of a certain attitude, and identifies with that attitude, will one derive any satisfaction from listening to, see- ing or being a punk. just as in the fifties there was an angry young man syndrome underlying popular culture so too one might consid- er punk in the same light. for both in terms of fashion and music punk saw itself as standing against the values and aesthetics of tra- ditional british society. indeed, the phrase anti-aesthetic used of such movements may be a telling one. for it seems plausible to hold that what is valued about punk is the underlying attitude rather than any intrinsic aesthetic merits possessed by the music. similarly it might be said that the grotesqueries of late michelangelo are valued because they express a disenchantment with the religious order of the world after the fall and sacking of rome. moreover grotesque, ugly and incoherent art- works may be valued by virtue of the way they enable us to explore our cognitive attitudes, beliefs and desires. so, in the case of a francis bacon, though horrifically ugly and repulsive, the work may have great appeal and artistic value because it enables us to confront and explore what it would be like if humanity were rotten, diseased, corrupted and distorted. t h r o u g h engaging with such artworks we may learn and develop our cognitive understanding of what certain human possibilities would or could be like.' o u r pleasure in such cases may arise from the provocation of cer- tain attitudes or our cognitive curiosity. artworks or movements devoted to the grotesque or incoherent are concerned to provoke certain attitudes or explore our fascination with certain anomalies which violate our standard social and moral categories. francis bacon's creations violate the natural order, the way humanity appears to be, and for this very reason compels our curiosity, inter- est and thus attention. yet, at the same time and for the same rea- sons, we find them aesthetically disgusting and repugnant. t h e abrogation of society's standard categories may be where both the fascination and aesthetic repugnance of such works lies. therefore, though they lack aesthetic value, such works may be of great artis- tic value. j noel carroll makes a similar point about the value of horror films in his the philosophy of h o r r o r ( n e w york: routledge, ), p p - . matthew kieran so cognitive value may explain why we attend to intrinsically unpleasant things in art and value them as such. furthermore, in engaging with artworks, we can afford to explore repulsive, grotesque and incoherent apparations and situations in a way we could not in the real world. for we cannot be threatened by an imaginary state of affairs in the way we could be if what we were imagining was actually happening. hence kve may enjoy contem- plating the ugly or incoherent in art, a matter which might not so readily give rise to pleasure if the situation represented were part of our everyday world and constituted an actual threat to ourselves. after all, the threat of chaos and incoherence in our lives hardly gives rise to pleasurable delight. by contrast, in art we can experi- ence what sheer chaos, ugliness and brutality might be like, and per- haps what it would be appropriate to think and feel, without the potentially terrible cost which would follow in the real world. therefore we can consider, provoke and satiate our curiosity about the grotesque, the ugly and the incoherent in art in ways we could or would not do in our everyday life. perhaps then, by divorcing aesthetic from artistic value, such an account can completely explain why we value such artworks. even as a psychological matter, it is often difficult for us to explore our curiosity about creatures, possibilities and events which challenge the way we categorize the world. t h i s may be due to social taboos or real emotional and physical threats. however, in art these constraints fall away and we can provoke, extend and indulge our curiosity. so the cognitivist can claim to resolve the challenge to the traditional picture of aesthetic value. for he rejects the notion that we aesthetically value the disgusting, ugly or incoherent, whilst nonetheless recognizing their cognitive virtues in works of art. t h e unpleasant appearances, thoughts and feelings are conceived of as unfortunate by-products of the cognitive pay-off. if we are to explore the ideas, concepts and categorial violations which give rise to the value distinctive of such artworks, the unpleasant by-prod- ucts are unfortunate but necessary. t h u s our interest in the ugly, incoherent or obscene lies in the curious violation of our social norms and conceptual framework. t h e fact that they are aestheti- cally unpleasant and repel us is the price we must pay. consider, in this light, the appeal of the dada art movement. t h e use of and delight in radical artistic practices used to subvert attempts to impose sense upon art, literature and the world was associated with a radical political standpoint. t h e reaction against figuration and artistic attempts to render the human world intelligi- ble suggests that dada saw itself in direct opposition not merely to the artistic but, more generall?; to the broader political and social aesthetic value: beauty, ugliness and incoherence status quo. perhaps without the use of these radical techniques which fractured the audience's ability to make sense of what was going on, dada would not have been able to question or stand against the way society was conceived to be. t h u s it is not that ugli- ness and incoherence are themselves intrinsically valuable in aes- thetic terms, but rather that under certain circumstances they can be used to make us confront and explore certain possibilities about our own society, possibilities we would not otherwise think about: t h e word dada symbolizes the most primitive relation to the reality of the environment; with dadaism a new reality comes into its own. life appears as a simultaneous muddle of noises, colours and spiritual rhythms, which is taken unmodified into dadaist art, with all the sensational screams and fevers of its reckless everyday psyche and with all its brutal reality. t h i s is the sharp dividing line separating dadaism from all artistic direc- tions u p until now ... dadaism for the first time has ceased to take an aesthetic attitude toward life, and this it accomplishes by tear- ing all the slogans of ethics, culture and inwardness, which are merely cloaks for weak muscles, into their components." indeed the whole point of foregrounding the construction of the artwork, in dada, brechtian theatre or nem wave french cinema, is to make us stop and think about the ways in which we can be lead into thinking certain institutions, social practices and structures are 'natural' and therefore cannot be changed. t h u s the usually nega- tive value of incoherence can have a positive value when it is artis- tically used to get us to see things in a new light. one key means of doing so in twentieth century art clearly involves the fracturing of our experience of the work, thereby foregrounding the verj- ways in which we attempt to impose sense upon our n o r l d . iv: the appeal of the grotesque yet though the cognitivist's explanation is partially adequate it can- not prove wholly so. for what is left out of the cognitivist account is the actual delight we feel in attending to repellent, ugly and inco- herent artworks. i t obviously makes sense to claim of a' dada piece that it is just not incoherent enough, of a stockhausen performance that it was just too harmonious or to say of a punk that he is just not as grotesque as he should be; and in all these cases we are disap- ' richard hulsenbeck, 'first german dada alanifesto ("collective dada hlanifesto)"', pp. - , in charles harrison and paul lyood (eds),art i n theory - (oxford: blackwells, ). matthew kieran pointed. t h e cognitivist equates these claims to the demand that they should explore more fully the relevant categorial violations. but the assimilation is a false one. imagine piss christ had the same title but did not in fact use urine as its medium. since we can treat the work as if constituted by urine this would hardly lessen the work's exploration of the divine as a being both of our human world and yet violating our standard cat- egories. yet, for some at least, this would significantly diminish the force and appeal of the work itself. on the cognitivist account, piss christ would be a better art~vork with a different medium. yet this is the exact opposite of what is the case. if the original medium was replaced then many would deem it to be of lesser value as art. t h i s is precisely because we enjoy and value the uncomfortable oscilla- tion between the beauty of the image and the repulsive material it is actually constituted out of, independently of whether it extends our curiosity about the image violating our standard conceptualization of the world. secondlq; the cognitivist's account works far better for our appre- ciation of francis bacon or andreas serrano than it does for ugly, brutal, chaotic images of war or grief. whether a depiction of war or grief is valued as art does not seem to depend upon its violation of our categorial schemes at all. for example, the work of goya, ugly) brutal tribal sculptures of various war gods, picasso's guernica or weeping woman seem, if anything, to confirm and extend, rather than abrogate, our understanding of violence, war or grief respec- tively. t h u s picasso states: if someone wished to express war it might be more elegant and literary to make a bow and arrow because that is more esthetic, but for me, if i want to express war, i'll use a machine-gun!' t h e value of guernica or weeping woman lies not in their con- fronting us with searing, repellent violations of our standard con- cepts. rather, their value lies centrally in their exploration of the vicious nature of grief and n a r respectively; which we can all rec- ognize and whose sheer raw poxver we should find discomforting, animalistic and repugnant. icioreover, the pleasure we feel does not just derive from the fact that the ug ; grotesque subject of the work is not a threat or open to our apprehension in el~eryday life. for in everyday life me sometimes do come across those unfortunate enough to be deformed, horrific conflicts or vicious forms of grief upon which, rather unfortunately, people are inclined to dwell. no ' picasso as quoted in a conversation on guernica recorded by jermoe seckler in excerpted in herschel b. chipp (ed.), theories o f iwodern art (berkley: c'niversity of california press, ). p. . aesthetic value: beauty, ugliness and incoherence doubt we are all familiar with the fact that pedestrians and traffic habitually slow down to take a good look at some unfortunate acci- dent victim. t h e cognitivist account fails not only to recognize that we may enjoy and savour the fundamentally repugnant, ugly and incoherent in art but, just as significantly, that some do so in their everyday lives. t h e cognitivist response fails to hit the target. even though part of the reason grotesquery, ugliness and incoherence are valued in art concerns their relation to our categorial schemes, this cannot be the tl-hole story. for many people just do delight in the presentation of the grotesque, ugly or incoherent features themselves. hence the appeal of the grotesque o l d ivoman, after quentin massys, c. , to be found in the national gallery, london, or christian schad's depiction of a g o s t a t h e pigeon-chested iwan a n d r a s h a t h e b l a c k d o c e , displayed in the royal academy's german art in the twentieth century exhibition. if a beautiful, coherent, non- grotesque and elegant subject and artistic means could be found to express the same attitudes a work would not necessarily be better, as it would have to be according to the cognitivist. if u n c h i e n a n d n l o u expressed the same point, the possible incoherence of the world, but was edited in such a nay that it did so coherently and devoid of horrific images, ive would have lost rather than improved the work's value of course, perhaps a certain attitude or disposition is required to delight in such features. one might even think that those who are petrified by the possible meaninglessness of the world will be unable, psychologically speaking, to cope with attending to works and features which manifest this possibility or delight in it. but the fundamental point is that we do not value ugliness, grotesquery or incoherence in the examples cited merely because they are taken to represent an attitude. for those who value them, the works and their typically repellent features are delighted in and savoured. t h u s we can make sense of the complaint, made of a portrait of a grotesque, dada piece or a punk rock track, that it is just not ugly, repugnant or incoherent enough. v: relational value different response would be to claim that although we do delight in the sound or look of features such as ugliness or incoherence it is only by virtue of their relation to other features of a work or other artistic movements. consider the following quotation from shakespeare's twelfth aright: matthew kieran o! what a deal of scorn looks beautiful i n the contempt and anger of his lip." part of the point of shakespeare's lines is precisely that the nor- mally distorted and horrific features of scorn and contempt them- selves become beautiful and pleasurable to dwell upon when mani- fested in the features of one who is both beautiful and beloved. t h u s what is normally repellent and harsh to look upon maq: given a certain context and relation to other features, become beautiful and pleasing. so, following sible?; it may be claimed that the aes- thetic value of features such as ugliness and incoherence may be, properly speaking, relational and wholly context dependent rather than being, as is the case with beaut); of autonomous aesthetic value." take atvay the relation and ive would not savour these fea- tures at all. for example, the deliberate incoherence and ugliness of punk rock or stockhausen were valued in contrast to ~ v h a t had gone before. xamely, a highly polished structural coherence and de\,el- opment of themes and harmonies which seemed too slick and empty. t h u s , in contrast to the formal elegance and beauty of prior music forms, punk and stockhausen were enjoyed precisely because they xvere not polished, slick or finished but grating, raw and appar- ently uncontrolled. it is a general feature of our understanding of art that it is neces- sarily comparative.'" o u r understanding of the nature and point of an artwork depends not just on attending to a work in isolation but, necessarily, to its place in an artist's oeuvre as a whole, the relation of the artist to a particular mo\-enlent and the relation between the movement to lvhich he belongs and the movements he conceives himself to be reacting to; lvhether it be in terms of repeating, extending or repudiating particular artistic traditions. a work's artistic value is intelligible if and only if \ve grasp its various rela- tions to the works and movements that preceded it. consider once more the dada art movement. only in the light of a classical art tradition and attempts to capture the essential, unchanging, eternal values of art which reasserted itself after the catastrophe of itorld \tar i , with which the avant garde's glorifica- tion of n-ar and machine aestheticism had been associated, can lve make sense of the assault attempted by dada on the cultural prac- tice of art. only given the predominant classical conception of art "shakespeare, tzcelfth sight ( ), act , section , . . frank sibley, 'aesthetic c o n c e p t s ' , plzilosopltical reciezc, h l . , , pp. - . ' i ' see david h u m e ' s essay. 'of t h e s t a n d a r d of t a s t e ' in his selected essays (oxford university press, ), s . copley a n d a . edgar (eds), pp. - . aesthetic value: beauty, ugliness and incoherence can we make sense of marcel duchamp's readymades as a jokey attempt to refute the presumption that good art must manifest an essential property or transcendent value. only in the light of a rea- soned, traditional conception of art do the essentially irrationalist and deconstructive techniques of dada make any sense. for if the classical tradition had not existed prior to dada then far from con- stituting an art movement what was produced would, in the most literal sense, have been nonsense. similarly, only in the light of a great classical tradition stretching from monteverdi through mozart and beethoven to elgar, does the music of john cage or stockhausen make any sense. for such movements are essentially negative in a deep sense; they are essentially repudiations of the artistic traditions that had evolved and developed pre\~iously over many ages. take away the tradition that is being repudiated and such music or art makes no sense. o n this story, then, features such as ugliness and incoherence may possess intrinsic aesthetic value but, unlike beauty, this value is only parasitic. t h e i r value is wholly supervenient on their relations to and the negative evaluation of other works and artistic traditions. take away the prior works and traditions and the relation to what is being repudiated disappears and, consequentl\; what merits the works have would vanish. hence, one might suggest, punk music died a predictable death once popular music became vital once more instead of slickly pursuing empty disco formulas. rjoreover, for those who continue to delight in the classical tradition, the appeal of cage and stockhausen remains deeply puzzling and unintelligible. t h e point is that features such as ugliness and incoherence may have an intrinsic aesthetic value only in certain contexts; where such features are used to react negatively against other artistic traditions. but beauty and coherence, by contrast, have an independent aes- thetic value which is not reducible to particular contexts and rela- tions, though what makes something beautiful may \\ell be context dependent. vi: freakish delights konetheless, although an appreciation of artistic traditions is required to understand how certain ~ v o r k s or artistic movements came about, and thus grasp a large part of their value, it cannot be the whole truth. for in the case of stockhausen, u n chien andalou and the portrayal of grotesques, we do consider the ugly and inco- herent features of the work to possess a certain positive aesthetic worth, independently of their relation to and our negative evalua- matthew kieran tion of other works o r artistic movements. hence, for example, we might like both soul music, elgar or hollywood films and the kind of works typified by punk, stockhausen's music or u n chien andalou. of course, part of the value of the ugliness and incoherence man- ifest in representational works which bear these features lies in their artistic rendering and the oscillation between the work and what it depicts. moreover, part of the enjoyment of these features arises from a contrast between the way the artistic object is and the way it could have been. for example, u n chien andalou works precisely because it sets u p all sorts of expectations and then proceeds to frus- trate them at every conceivable t u r n . t h e characters change, just as a narrative line suggests itself it is cut off, the images clash and so on. similarly, part of the attraction of grotesques lies in the very disjunction between what, had they been normal they would have been like, and the distorted, corrupted, freakish physiognomies we see before us. we look at what is presented to us and value it at the meta-level for its frustration of our expectations and the oscillation between what we see or hear and ~ v h a t we would normally expect such works or people to be like." yet the attraction cannot entirely rest at the meta-level. for we may just delight in and savour what is ugly and incoherent, which ties in with a certain kind of human fascination for the freakish or horrific. indeed, consider leontion's story as recounted by plato in the republic: he noticed some corpses lying on the ground with the execution- er standing by them. h e wanted to go and look at them, and yet at the same time held himself back in disgust. for a time he struggled and covered his eyes, but at last his desire got the bet- ter of him and he ran up to the corpses, opening his eyes and say- ing to them, ' t h e r e you are, curse you,-a loeely sight! have a real good look."' t h e point is that leontion's delighting in the corpses, analogous to punk's delight in complete ugliness or incoherence in both style and music, suggest that it is the grotesque features which are themselves delighted in. of course, one might hold that it is a purely contin- gent matter as to whether people actually savour intrinsically i' t h i s kind of line is suggested by jerrold lei-inson, 'pleasure and the value of [vorks of a r t ' , b v i t i s h journal of a e s t h e t i c s , vol. , no. , , p. . l plato, t h e republic, trans. d. lee, (harmondsworth: penguin, ), nd edn, book i\: pp. - , . e- . a. t h e italics are my own, to emphasize that leontion delights in the sight of the corpses. aesthetic value: beauty, ugliness and incoherence unpleasant features such as ugliness." t h e thought is that it is not the intrinsically unpleasant features and our subsequently unpleas- ant response that are delighted in but, rather, only the features of the object which give rise to an unpleasant, unsavoured response. recognizing that delighting in the grotesque, ugly and incoherent may be aesthetically rewarding does not entail that what is ugly, grotesque or incoherent is a contingent matter. for there are certain ideal human standards by virtue of which it is appropriate to derive pleasure from certain things and be repelled by others.i certain tastes or sensations are pleasurable under certain standard and nor- mative human conditions. in normal cases where someone fails, say, to delight in quenching their thirst or in being reunited with a friend we look for an explanation. if the failure to derive pleasure from such cases is beyond the standard limits of taste or desire vari- ation, then it must be explained in terms of the subject's divergence from our norms of desire. however, in secondary cases, where we can inhibit or modify the standard conditions through interference or convention, then sensations which are typically unpleasant may become pleasant and vice versa. t h u s , a delight in our reponses to ugliness, incoherence and the grotesque may constitutively include negative or positive evaluative thoughts and are individuated according to their formal object. ugliness, incoherence and grotesquery which give rise to a response of disgust may intrinsically afford great pleasure, though we might evaluate them as undesireable. for we may delight in what we (ought to) desire not to desire.i t h e attractions of activi- ties such as sado-masochism are not reducible to the controlled rit- ualistic role play which enables people to engage in and enjoy activ- ities that, outside such a controlled artificial context, would both be highly dangerous and socially threatening. t h e fact is that such activities are pursued because they focus upon and afford a pleasur- able delight, which is savoured, in the infliction of pain and brutal- ity. but such a delight is intrinsically perverse since our evaluation i' see kendall walton, m i m e s i s as m a k e believe (cambridge, mass.: harvard university press, ), p. , and alex neill, 'on a paradox of the heart', philosophical s t u d i e s , \'ol. , , pp. - . " see alasdair macintyre's 'pleasure as a reason for action' in his a g a i n s t t h e s e l f i m a g e s of t h e a g e (london: duckworth, ), pp. - . see berys g a u t , ' t h e paradox of horror', b r i t i s h j o u r n a l of aesthetics, ' . , no. , , pp. - , makes this point in relation to o u r enjoyment of fearful and horrific fictions. '"ee david lewis, 'dispositional theories of value', a r i s t o t e l i a n s o c i e t y s z ~ p p l . v o l . , vol. l x i i i , , pp. - . matthew kieran of such a delight resulting from a perverse desire ought to be nega- tive: we ought to be ashamed of desiring and delighting in the painful, the brutal and the downright dangerous. indeed, if some- one were not only to take delight in such activities but evaluate them positively, then we would take this as a mark of a perverse charac- ter. as i have argued ugly, incoherent and grotesque artworks can and sometimes do afford us aesthetic pleasure. hence from bacon's bru- tal vision of the human condition through picasso's searing depic- tion of grief to serrano's piss christ, stockhausen or punk rock we can appreciate why many people appropriately consider them to possess aesthetic value. typically unpleasant features, characters or states of affairs may be of aesthetic value and cannot be wholly explained away as unfortunate by-products of something else we derive pleasure from. rather they may afford pleasure, at least to those with an aesthetic sensibility directed toward the chaotic, ugly and incoherent, in attending to them. so the standard account of aesthetic value holds good but only if we are careful to distinguish, as too many people often fail to do, between aesthetic and artistic value. hence it makes sense to complain that a punk's outfit is not inco- herent enough, that the grotesque depicted in a portrait is not ugly enough or that u n chien andalou could have been more fractured. moreover, we do not delight in these appearances merely because they confirm our responses as appropriate. leontion does not thrill to the sight of the corpses merely because it confirms to him that he is the kind of person who is afraid of death. for leontion's pleasure is not dependent upon him refraining from looking at the corpses but rather precisely in his dwelling upon them. t h e very sight of the distorted, dehumanized corpses is an essential part of the delight he takes in his enjoyment of looking upon them. such unpleasant sights themselves can actually afford us a peculiar kind of aesthetic pleasure. of course we may need to have a certain attitude or disposition in order to take delight in the ugly, grotesque or incoherent. i think this is certainly true of much post-modern and nihilistic art, which places primary aesthetic value on the chaotic, incoherent and grotesque, certainly above and beyond formal elegance, grace and unity. hence the aesthetic value here is perhaps best captured in terms of kant's dependent beauty. but in so far as kant's contrast between free and dependent beauty is meaningful, not all the delight we take in ugliness and incoherence is dependent.'' " immanuel kant, the critique of judgement, trans. j. c. meredith, (oxford university press, ), book , section , pp. - . aesthetic value: beauty, ugliness and incoherence sometimes, we just do delight in the appearance of ugliness. for example, in yorkshire there is a great tradition of gurning. gurning essentially involves competing to see who can pull the most distort- ed and ugly faces possible. similarly, the pull of freak shows would be unintelligible if we did not derive pleasure from gazing on the ug ; grotesque and deformed. t h u s , atypically at least, we do derive pleasure from and delight in the grotesque, freakish or chaotic. what i have tried to show is that far from constituting counter examples to the traditional understanding of aesthetic value, if worked out carefully, ugliness and incoherence, contrary to first appearances, conform to it. what this points up, pace beardsley et al, is the danger of deriving overall aesthetic principles of evalua- tion from the paradigmatic case of beauty. what we delight in, aes- thetically speaking, may be far from delightful. vii: ethical afterthoughts i t is important to point out that a perverse fascination for and delight in the freakish is, in a significant sense, perverse. of course, it might be pointed out that art which confronts and pushes back the boundaries of our ethical and social taboos may be valuable in chal- lenging various prejudices. t h u s confronting the viewer with the ugly, the grotesque or incoherent may usefully challenge our com- fortable assumptions about normality, beauty and the ways in which we make sense of our world. but it is far from clear that pushing back the boundaries of our ethical and social presumptions, at least for its own sake, is a good thing at all. for the corrosion of our natural human bonds may lib- erate us, but liberation from the self-discipline of moral and social restraints upon the violent, ugly and brutish aspects of our animal natures is clearly a bad thing. what marks out human civilization, as distinct from animal behaviour, is precisely our self-conscious suppression and sublimation of our animal natures toward what is, humanly speaking, rational. artworks which cultivate the delight in our baser non-rational appetites are thus humanly impoverishing and bad as art. indeed, it is interesting to note that the preoccupation with inco- herence, violence and perverse pleasures in art tends to occur after ''see hiatthew kieran, ' t h e impoverishment of a r t ' , britishjournal of aesthetics, vol. , no. , , pp. - , and 'art, imagination and the cultivation of morals', journal of aesthetics and a r t critirisnz, vol. , s o . . fall . matthew kieran the apparent perfection of a form of a certain kind. for example, jacobean drama's preoccupations are partly a result of the perfec- tion reached by shakespearean tragedy; so there is nowhere left to go but down toward pandering to our more perverse pleasures." t h e slide toward decadence is deeply interesting. but although aes- thetically valuing such things ma!- well be the mark of a juvenile or morally bad character, this is a separate matter from the question of- pure aesthetic value. artistic value is broader than mere aesthetic value. tthen people object to something as obscene they are often not disputing that the work concerned has, or can be seen by some to have, aesthetic value. rather what underlies the condemnation is the thought that though aesthetically attractive in a certain light, what is represented and how it is conveyed is morally repugnant. a morally or religiously obscene image is not denounced merely by virtue of the subject matter, but because the focus of interest is merely the particularities of the ugl?; repulsive medium used, for instance the urine in andreas serrano's piss christ, or the tedious, unimaginative con- centration upon the perennial repetition of images of violence and death, as in damien hirst, or images of sexual congress, as in the work of jeff koons, without any distinctively artistic achievement. i t is interesting to consider in this light john ruskin's thoughts on the late renaissance in the s t o n e s of venice. ruskin recognized that the art of the period was devoted to the pursuit of pleasure, which we would characterize as aesthetic, but did so only given a debased delight in brutal mocker); monstrosity and deformity at the expense of insight into or the transcendence of our human condition. hence when describing a sculpture at the base of the t o u e r dedicated to s t . hlary the beautiful ruskin comments thus: a head,-huge, inhuman, and monstrous,-leering in bestial degradation, too foul to be either pictured or described ... in that head is embodied the type of evil spirit to which venice \vas aban- doned in the fourth period of her decline.'" ruskin is not disputing that, seen under a certain light, the sculp- ture may be aesthetically rewarding. rather he is objecting to such things as 'evidences of a delight in the contemplation of bestial vice, and the expression of low sarcasm, \vhich is, i believe, the most hopeless state into which the human mind can fall.'" t h e point is that we can give a story about the aesthetic appeal of such images, ' ' i t h i s example mas suggested to me by roger vhite. "' john ruskin, t h e s t o n e s of vetzzce (london: smith, elder and co., ), vol. , chapter , section xi: p. . ibid., section x ' , p. . aesthetic value: beauty, ugliness and incoherence yet the kind of interest rewarded by this form of aesthetic attention is a perversion of art proper. perhaps, as robert hughes has sug- gested, a large part of the story may be told in terms of the degen- eration of modern art coupled with an obsession with the external vagaries of fashion and the commercial m a r k e t p l a ~ e . ~ ~ what this does suggest is the extent to which, though producing aesthetically appealing works, such artists and much contemporary art has failed our culture. but this leads us into plato's worry about the arts and that is a question that can only be addressed elsewhere." unicersity of leeds '' robert hughes, ' t h e decline of the city of mahagonny' in his -yothing if s o t cuitical (london: collins harvill, ), pp. - . 'i plato, the republic, trans. \t. k . c. guthric, (harmondsworth: penguin, ), book x, pp. - . t h i s paper is a h e a d > - modified version of one presented at the flemish society of aesthetics conference in antwerp, - september, , in whose proceedings a summation of the earlier version is due to be p u b - lished. i would like to thank all those present, and roger if'hite, for their helpful comments. contentserver.asp.pdf women’s studies, : – , copyright © taylor & francis group, llc issn: - print / - online doi: . / gwst - - women’s studies, vol. , no. , aug : pp. – women’s studies black women, beauty, and hair as a matter of being black women, beauty, and hair as a matter of beingcheryl thompson cheryl thompson mcgill university, montreal if a woman has long hair, it is a glory to her; for her hair is given to her for a covering. — corinthians : since i was a teenager, i have chemically altered the natural state of my hair. at the time, i never really thought about why i did it, or the extent to which that chemical would rule over me. but my hairstory is not unique. for the vast majority of black women, hair is not just hair; it contains emotive qualities that are linked to one’s lived experience. the crux of the black hair issue centers on three oppositional binaries—the natural/unnatural black, good/bad hair, and the authentic/inauthentic black. on the one hand, scholars in the caribbean, britain, and the united states speak of the importance given to the dominant beauty paradigm, which privileges “white/light skin, straight hair and what are seen to be european facial features” (tate ). on the other hand, the legacy of the s and s black power movement is that blackness was redefined such that afrocentric or “naturally” black hairstyles became associated with the authentic. as such, “within this black anti-racist aesthetic the beauty that was valorized and recognized was that of ‘dark skin’ and ‘natural afro-hair’. . . the only authentic black hairstyles would be dreadlocks, afro, cane-row and plaits. by extension, the only authentic blackness would be a dark-skinned one. these are the valorized signifiers of the ideal of ‘natural black beauty’” (tate – ). this article uses causal talk about hair to examine how media and social interactive processes mediate one’s grooming choices while simultaneously ascribing an aesthetic value on one’s body. address correspondence to cheryl thompson, saint mathieu, apt. , montreal, qc, canada h h s . e-mail: musiqwriter@gmail.com or cheryl.thompson@mail.mcgill.ca cheryl thompson the black and bi-racial women featured in this article demon- strate the depth and breadth of issues that arise when black hair is discussed. using social comparison theory as a framework, i argue that the eurocentric beauty standard of straight, long and flowing hair has a sociocultural affect on black women’s notions of physical attractiveness, but also on courtship, self-esteem, and identity. leon festinger’s social comparison theory suggests that people compare themselves to others when they are not certain about themselves. ultimately, this article seeks to explain the dis- crepancy between desired and perceived beauty and how such perceptions lead black women to engage in hair practices designed primarily to align themselves with the dominant beauty standard. in order to understand the complexity of the juxtaposition between adhering to eurocentric beauty standards and the assim- ilatory cultural practice of hair straightening, i first review the his- tory of black hair and hair altering techniques. second, i explain how and why social comparison theory is a valid measure to eluci- date black hair issues, especially since beauty is subjective. third, i contemplate the ways in which hair length and texture perform as a marker of femininity; the western beauty ideal and the pres- sures to conform to this ascribed beauty aesthetic, and how such conformity contributes to conceptualizations of what it means to be physically attractive, and sexually desirable. finally, i critique the politics of black hair in the workplace, exploring the question of why black hair continues to be eyed as a threat to the domi- nant hegemonic beauty ideal. a history of black hair hair. it may seem like a mundane subject, but it has profound implica- tions for how african american women experience the world. —lanita jacobs-huey ( ) i conducted interviews with these women in july . the interviews were done both in person and via telephone and transcribed by myself. in discussion with them, we agreed to use an alias name to protect their privacy. i have personally known these women for several years, with the exception of one, who was referred to me by one of the women interviewed. participants were caribbean and caribbean and indian descent and lived in toronto and hamilton, ontario, canada. black women, beauty, and hair as a matter of being several african-american scholars have explored the history of black hair from pre-slavery africa to contemporary times (banks – , ; byrd and tharps – , ; mercer – ; rooks – ). prior to the transatlantic slave trade, black hair denoted cultural and spiritual meanings for both men and women. while some of the hairstyles that were dawned by africans during this period are still worn today, including twists, braids, zulu knots, nubian knots, and dreadlocks, once the slave trade began, the african’s connection to their hair was forever altered, and com- plicated by life in north america. forced to work in the fields all day, there simply was no time to care much about one’s appear- ance or one’s hair. moreover, “treasured african combs were nowhere to be found in the new world, so the once long, thick, and healthy tresses of both women and men became tangled and matted” (byrd and tharps – ). where women, in particular, used to meticulously craft elaborate hairstyles back in africa, once in the new world (america, the caribbean, and canada) they took to wearing head scarves or handkerchiefs atop their heads, partly to shield themselves from the sun, but also to hide their unsightly, unkempt hair. in years without a comb, willie morrow chronicled the history of black hairstyling practices, arguing that skin color and hair are so intertwined that it is hard to separate the two when examining the forces that shape black people’s lives. morrow argued that “[hair] is the basic, natural symbol of the things people want to be . . . and its social-cultural signifi- cance should not be underestimated” (qtd. in banks ). during the th century, it was fashionable for white men of the upper class to wear wigs; in turn, slaves who worked in the “big house” also took to wearing wigs, while others shaped their own hair to look like a wig. in order to further distance blacks from their cultural roots, and denigrate any attempts to hang on to such african hair traditions, during this period, european scientists began to categorize the appearance of blacks in the new world, including hair and skin tone. dominated by fair skinned and straight hair people, “african hair was deemed wholly unattractive and inferior by the europeans. many white people went so far as to insist that blacks did not have real hair, made famous by reggae singer and rastafarian bob marley, dreadlocks have their roots in african culture, and still carry many negative connotations for people who wear them. cheryl thompson preferring to classify it in a derogatory manner as ‘wool’” (byrd and tharps ). further, once black beauty was juxtaposed with white beauty, a socially stratified hierarchy began to take shape. by the time slavery was abolished in the late th century, “the goal of grooming the hair had morphed from the elaborate and symbolic designs of africa into an imitation of white styles adapted to black kinks and curls. . . . there existed neither a public nor a private forum where black hair was celebrated” (byrd and tharps ). as free blacks left their plantations, demarcations related to straightened black hair began to circu- late. in her historical review of early th century advertisements, noliwe rooks found that the products that were advertised regu- larly included before and after pictures encouraging black women to lighten their pigment and straighten their hair, if not for themselves, but for their community. these advertisements, as rooks notes, “argue for the desirability of changing physical manifestations of ‘classic’ african features by juxtaposing the characteristics of caucasians and africans to highlight the advan- tages of disavowing the physical manifestations of an african ancestry” ( ). in conjunction with such advertisements, black entrepreneurs recognized the tremendous opportunity to market and sell products to blacks—especially women—that would simi- larly appeal to the need to assimilate into white culture. madam c.j. walker’s hair softener, which was accompanied by a hair-straightening comb (known as a hot-comb), is regarded as the first hair product developed and manufactured by, and sold to, black people. walker revolutionized the way black women thought about their hair. because she was also black, not only did her product sanction the act of straightening, it also turned it from something whites had demanded that blacks do into a collective signifier of progress. as tracy owens patton argues, according to rooks’ research, by the turn of the th century, ads for ozonized ox marrow showed in the “before” drawing, the woman’s hair almost standing on end, where- as the “after” drawing portrays the hair as neatly combed and styled. the advertising copy proclaims, “this wonderful hair pomade is the only safe preparation in the world that makes kinky or curly hair straight.” finally, advertisements for curl-i-cure: a cure for curls said, “you owe it to yourself, as well as to others who are interested in you, to make yourself as attractive as possible. attractiveness will contribute much to your success—both socially and economically. positively nothing detracts so much from your appearance as short, matted un-attractive curly hair” ( – ). black women, beauty, and hair as a matter of being “walker’s beauty empire, therefore, not only contributed to higher self-esteem among the black community, but also created a new job industry for those who attended her beauty schools” ( ). and while walker’s astute entrepreneurial endeavors make her an undeniable trailblazer, “by the mid- s, however, straight hair had become the preferred texture to signal middle- class status” (rooks ) not natural black hair, in large part due to her efforts. walker may have positively reinforced the act of straightening one’s hair, but during the black is beautiful move- ment of the s and s, hair alteration became a contested practice. the “shift to calling oneself black and being proud of it translated into a style that proudly hearkened back to africa” (byrd and tharps ). this shift was largely sparked by the hair- styles of such performers as james brown, sammy davis jr., and cicely tyson, who all wore afros and braids during the s. the aforementioned also contributed to demarcations surround- ing an authentic and inauthentic blackness. those who wore an afro were also wearing another look, known as the “natural,” which was “unstraightened black hair that was not cut close” (byrd and tharps ). ultimately, the ideological shift in black hair coin- cided with a political shift. a “real” black person adorned a “natural” hairstyle, while those who straightened their hair were deemed fake for attempting to emulate a white aesthetic, and an “unnatural” black look. today, hairstyles run the gamut from afros to straightened hair to jheri curls, irrespective of skin tone, socio-economic class, and political affiliation. however, this article aims to debunk the idea that black hair is no longer political or “just hair.” first, at the same time black people have a plethora of hair options at cicely tyson, an african-american actress, is touted as one of the first women to adorn a natural hairstyle on television. as bryd and tharps recount, “in , cicely tyson appeared on the cbs drama series east side, west side with her hair in an afro and, in subsequent episodes, in cornrows” ( ). while it would be several years later that the wearing of an afro meant an allegiance to africa, nonetheless, tyson’s hair was ground- breaking at the time. made popular in the eighties by black celebrities of the day, the jheri curl was essen- tially a chemical added to the hair that gave the appearance of tight, curly hair. it required an activator, aka “jheri curl juice,” and a shower cap to keep the moisture in one’s hair. when michael’s jackson’s jheri curl caught fire during the filming of a pepsi commercial, the style began to fade. cheryl thompson their disposal, there have been punitive measures taken by employers to restrict the donning of the “natural” in the work- place. in the case of rogers v. american airlines for example, the court “upheld the right of employers to prohibit categorically the wearing of braided hairstyles in the workplace. the plaintiff, a black woman, argued that american airlines’ policy discrimi- nated against her specifically as a black woman . . . the court chose, however, to base its decision principally on distinctions between biological and cultural conceptions of race” (caldwell ). in , a black woman in west virginia was fired from her job at a prison for wearing braids, which was deemed to be inappropriate —even by penal standards. while the argument can be made that black hair no longer carries the same socio- cultural significance it did in decades and centuries past, the “natural” remains an unwanted politically charged marker in the workplace. as lori s. robinson writes, “corporate america isn’t the only adversary of natural styles. some black institutions dis- courage the ‘natural’ look, believing it’s best to prepare african americans to blend into a majority-white corporate environ- ment” ( ). second, perhaps fueled by hip-hop culture and its images of pimps, thugs, and gangsters who wear cornrows and braided hairstyles, a review of the discourse on black hair shows very little acceptance of natural black hair. in the hair in black women, dr. neil persadsingh, a trained dermatologist (who is light-skinned with curly wavy hair) provides a guide to styling, grooming and treating black hair. in describ- ing the genetics of black hair, persadsingh writes: black hair has some advantages, especially in a hot climate. . . . caucasian hair offers better protection against the rain compared to black hair, but water runs off it rapidly with little lasting cooling effect. ( ) this is an excellent example of the ways in which black hair con- tinues to be juxtaposed with “caucasian” hair as being inferior to, or in need of fixing. while black hair has “some advantages,” . i cannot recall the woman’s name but this was a topic of discussion on the michael biesdon syndicated radio show on september , . i presume persadsingh’s use of the word “caucasian” is meant to include all ethnici- ties other than african descendants. black women, beauty, and hair as a matter of being persadsingh implies that the negative aspects of the “natural” aes- thetic far outweigh the positive. similarly, in her book, the guild to styling and grooming black children’s hair: it’s all good hair, michele n.-k. collision uses language that prioritizes straightened hair over afrocentric styles. in describing whether or not a parent should put their child’s hair in dreadlocks, collision writes: locs are not for every child. the hairstyle is permanent. if your daughter or son is the type who wants a new hairstyle every couple months, tell her or him to try a different style. . . . locs are recommended for children who are confident and can talk about their hair choices. a lot of people don’t understand locs and may say cruel things to children about their hairstyle. when his friends start to call him “buckwheat,” he may decide he doesn’t want locs. ( – ) conversely, she describes chemically “relaxing” a child’s hair as follows: you’ve all seen the pretty pictures of the little girls on the perm boxes with the beautiful, bouncy hair. lately, you’ve been thinking that relaxing your child’s hair would make your life much easier because you wouldn’t have to spend so much time managing and styling it. or, maybe it’s your daughter—or even your son—who’s pushing for the change. ( ) it is the contemporary discourse on black hair that reminds us that it is still a contentious issue. while their respective works pro- vide necessary styling guidance on different types of hair textures, both collison and persadsingh demonstrate how straight hair, which is more aligned with western beauty ideals, continues to be privileged over natural styles—especially dreadlocks. it is impor- tant to note that hair straightening has been challenged as an expression of collective pride, not as a badge of self-hate. accord- ing to paul taylor, hair straightening “has taken on such racial- ized significance that participation in the practice can be a way of expressing black pride rather than a way of precluding it” ( ). further, charisse jones and kumea shorter-gooden argue that “not every woman who decides to straighten her hair or change buckwheat was a black character in the s television show, the little rascals. his appearance was largely an exaggeration of blackness, and by today’s standards, is quite offensive. as such, collison makes the reference here to connote the negative reaction people who wear dreadlocks will likely receive. cheryl thompson the color of her eyes . . . believes that beauty is synonymous with whiteness. trying on a new look, even one often associated with europeans, does not automatically imply self-hatred. it is possible to dye your brown tresses platinum and still love your blackness” ( ). for some, hair alternation is a matter of personal choice, thus, the question this article aims to examine is whether straight- ened hair should be considered just another option amid a plethora of styling options, or whether all hair—natural or unnatural— should be critically evaluated as kobena mercer suggests, “as an aesthetic practice inscribed in everyday life, all black hairstyles are political in that they each articulate responses to the panoply of historical forces which have invested this element of the ethnic signifier with both symbolic meaning and significance” ( ). social comparison theory and hair social comparison theory provides a measure to understand how and why people compare themselves to societal standards when assessing their own behaviors. with respect to beauty, this theo- retical framework can provide a critical tool to evaluate a woman’s hair choices, and the ways normative hair standards are used to evaluate one’s level of attractiveness. as law and labre describe, “once a comparison is made, assuming that the person wants to be similar to and ranks the other person as superior, then the existence of the discrepancy will result in action on the part of the person making the comparison in order to reduce the discrepancy” ( ). there are several examples where social com- parison theory has been used in gender studies involving physical attractiveness and self-esteem. thornton and moore found that women’s self-ratings of attractiveness and social self-esteem were lower after exposure to a physically attractive, same-sex model than after exposure to a physically unattractive, same-sex model ( – ). when it comes to body shape, researchers have found that black women are not strongly affected by mainstream body standards of beauty, which is consistent with findings that black women have greater body satisfaction than do white women (e.g., evans and mcconnell ). beth molloy found that unlike white american women who are plagued by waif-like images they cannot attain, african american women are relatively positive about their body image, as she writes, african-american women black women, beauty, and hair as a matter of being “believe that african-american males prefer larger women, they have less need to lose weight, and therefore, feel more attractive” (qtd. in patton ). however, this finding does not take into consideration the images of hair that are disseminated by mainstream media. understanding the intersection of social com- parison and hair gives us deeper insight into why black women find it difficult to resist aligning their hair choices with that of the dominant beauty ideal. the juxtaposition of in-group compari- sons and social interactive processes also provide valuable insight into the pressures to conform to mainstream standards of long, flowing, and straight hair. hair texture and identity good hair means curls and waves bad hair means you look like a slave —india arie it has been over ten years since i last combed my hair. when i mention this, friends and family are sometimes scandalized. i am amused by their reactions. during the same ten years they’ve poured gallons of possibly carcinogenic “relaxer” chemicals on themselves, and their once proud, interestingly crinkled or kinky hair has been forced to lie flat as a slab over a grave. but i understand this, having for many years done the same thing to myself. —alice walker a fundamental question that all black women, irrespective of skin tone, hair type and socio-economic class have asked themselves at one point in time is: what am i going to do with my hair? black hair, in all its manifestations, must always be contemplated. byrd and tharps argue that “it is impossible to ignore the fact that pop culture paradigms of beautiful black women are coiffed with long, straight hair” ( ). during conversations with “mixed race” black women in britain, shirley tate notes that “shade and its companion hair, matter for acceptance into black community” ( ). specifically, one of tate’s respondents cited that when lyrics are from the song, “i am not my hair” off arie’s album, testimony: vol. , life & relationship ( ). mastalia and pagano, . cheryl thompson faced with the denial of black people in her youth, she plaited her hair and wore an african head-wrap to hide the straightness of her hair, an act which supports judith butler’s concept of per- formative reiteration, in that black beauty, following butler’s argument, is a matter of doing and its effects are not therefore an inherent attribute. rather, it is about “racing” bodies and being raced by embodied subjects ( ). for instance, latoya recalls a childhood visit to new york and how exposure to african-american culture shaped her hair choices; and rebecca, in talking about her experiences going to a black hair salon, illustrates how and why for “mixed race” women, “shade and hair are . . . refigured as an absence such that black can be rendered present in every account of beauty while ‘mixed race’ is erased as a source of iden- tification” (tate ): latoya i used to go to the states and hang out with some of my cousins who were quite a bit older and they used to have their hair relaxed like everybody had their hair relaxed. nobody had natural hair in new york; that was the style and that was what the cool kids were doing. . . . i think prior to that i would wear my hair in two plaits down my head or something like that and nothing fancy or anything like that. i wanted to be doing whatever the cool kids were doing. rebecca when you’re half or when you’re “mixed race” it’s difficult to fit in because you’re many things. it’s difficult to find similarities between people, culturally or community speaking wise and i think i just felt really isolated and i felt i finally found somewhere where i felt like african beauty or hair was celebrated . . . black hair in its natural state is often negatively marked for its difference. while white women have lots of issues about their hair, “they also have lots of affirmation for their hair. [black peo- ple] don’t have the overall cultural affirmation that counters the negative obsession” (qtd. in byrd and tharps ). for example, byrd and tharps further argue that “since the beauty standards in [america] are set according to a white aesthetic—from miss america to the barbie doll—black women are left with precious few places to find an image of beauty that showcases unstraight- ened tresses and natural styles” ( ). further, “hair functions as a key ethnic signifier because, compared with bodily shape or facial black women, beauty, and hair as a matter of being features, it can be changed more easily by cultural practices such as straightening” (mercer ). when asked about her earliest childhood memory about her hair and its difference, sheila told me: “i would say probably when i was around eight. i used to . . . wear blankets on my head and wear headbands to hold the blan- kets and i’d pretend that it was my hair . . . i think that’s when i really noticed that i didn’t like my hair, well i don’t want to say i didn’t like my hair but i preferred the longer hair.” historically, white women have also been forced to adhere to a beauty standard that is often unattainable. in the th cen- tury, “ample breasts, hips, and buttocks became the beauty ideal” (patton ); then in the th and th centuries, women contin- ued to wear corsets to exaggerate small waists, despite adverse effects on their physical health. in the th century, a similar pre- scribed beauty ideal became ubiquitous and entrenched. impor- tantly, not all racial minority groups have been affected the same by such standards. evans and mcconnell found that black women and asian women, although both racial minorities, respond differently to mainstream standards of beauty. specifically, “although black women may employ self-protective strategies while comparing themselves to mainstream standards of beauty . . . asian women were less likely to utilize such strategies. instead, asian women appeared to adopt non-ingroup, mainstream beauty ideals” ( ). second, they found that “asian women resemble white women in their desire to strive for mainstream beauty ideals” ( ). while researchers argue that black women do not sub- scribe to the same thinness ideals that are prescribed in main- stream culture (e.g., evans and mcconnell ), through their hair, black women are similarly struggling to adhere to main- stream beauty ideals. importantly, frantz fanon first regarded cultural preference for all things white as symptomatic of psychic inferiorization; however, if black hair, and all human hair, has no inherent aesthetic value in that it must be worked upon before it can be beautiful (mercer ), what peculiarities distinguish black hair from other types of hair? as midge wilson and kathy russell found, “hair becomes such a major preoccupation for there has yet to be quantitative or qualitative comparison research done to affirm or disaffirm the argument i put forth here. cheryl thompson adolescent girls of both races that their self-esteem can actually rise and fall with every glance in the mirror” (qtd. in patton ). since black “hair decisions are subject to more critical feedback from friends, because hair styles are laden with political overtones” ( ) the aesthetic stylization of a black woman’s hair, whether inten- tionally or unintentionally, “seeks to revalorize the ethnic signifier” (mercer ), and reduce the impact of psychic inferiority. for example, african-american writer, akkida mcdowell’s recollection of her childhood illustrates how black hair is as an ethnic signifier that requires action: when my hairstyle differed from the elaborate norm, my classmates and peers viewed me as unacceptable. . . . if my hair didn’t look good (to them), i wasn’t any good. my hair dictated whether i went out or not. on days that my hair acted up, the tv kept me company. according to movies, my beloved television, my classmates and even my neighbors, a proper hairstyle not only completed the package, but defined and delivered it. ( ) similarly, jackie, vanessa christine, nicole, and tracy all give accounts from their childhood that highlights the power of social comparison. their comments also illustrate how through the physicality of hair, black women are caught between what mercer describes as two logics of black stylization—one emphasizing natural looks, the other involving straightening to emphasize artifice: jackie when i got to school . . . considering that my brother and i were the only two black kids in the whole school i learned early that my hair was differ- ent. . . . if my hair wasn’t braided and my mom let it out, they would be like, ‘your hair is so spongy’ and they always liked to touch it, it was proba- bly grade when i noticed. vanessa when i was in elementary school, grade four or grade five . . . being a young kid, it really caused me to be a little more self-conscious of my hair. . . . my hair made me different . . . there were a lot of different races where i grew up and i’m not sure how my other friends felt about it but i always felt definitely that they were intrigued by my hair. christine my mom has always pressed her hair since i was a kid and a person who was not of our culture came over and saw her pressing her hair and actually said, black women, beauty, and hair as a matter of being ‘your mom is putting fire in her hair!’ so that to me was a wake up call because i realized that what we do to our hair is tantamount to torture compared to other people who have straight hair, more manageable hair. nicole i was one of the lucky kids i guess because everyone back in the day was like ‘oh, you’re hair has to be long to be beautiful’ and my hair was . . . i was always asked to wear my hair out to school but then . . . people would always want to touch my hair and be like, ‘oh you hair is so nice, can i touch your hair?’ tracy i think it would probably be when i was really consciously aware was prob- ably grade . . . . because at that point i started to not go to school with my hair braided in plaits, i was starting not to do that and sort of trying differ- ent styles and i realized that i had limited styles that i could do and get away with going to school and still look decent. hair straightening is not only linked to physical attractiveness, it is also a marker of socio-economic mobility; as noliwe rooks recalls, “my grandmother believed i would be ostracized by middle-class african americans if i did not straighten my hair” ( ). historically, the idea that straight hair means higher social and economic opportunities was spearheaded by c.j. walker; however, by the mid- s white-owned companies recognized that black women were a multiple product-dependent market, desperate to move up the social and economic ladder. thus, such companies as “vaseline and dixie peach . . . established them- selves as key players in the hair game” (byrd and tharps ). the black hair industry was dominated by white-owned companies up until when african-american george e. johnson created the first “permanent” straightening system that could be applied in one’s home. although the black is beautiful movement valo- rized a natural aesthetic over a chemically treated one, that ethos could not be maintained; albeit, it did have a short lived revival in the s. during this second hair movement, “black women started wearing their hair in intricate african-inspired braided styles, which launched an enormously successful business for immigrant african hair braiders” (byrd and tharps ). hair braiding was so circa . cheryl thompson popular during the s that vanessa, who grew up during this period said, “i would get my hair braided almost every summer either with extensions or my own hair. i don’t know if you remember sheneneh from martin that tv show but she was the only character at the time that was black and had braids.” once again, hair manufacturers seized an opportunity to introduce new lines of sprays and sheens for natural hairstyles, and just like in the past, white-owned companies again dominated the market with products like african pride, which was “packaged in the african nationalist colors of red, black, and green” (byrd and tharps ). each of the women i spoke to at one point in time chemi- cally straightened their hair. interestingly enough, their reasons for doing so were in large part due to a growing tiredness with their natural hair, and the fact that they came of age during a period—the late s and s—where chemically straight- ened hair was an easy option (or quick “fix”) at their disposal: latoya i got my first relaxer when i was about or maybe. living in the com- munity that we lived in there wasn’t any black hairdressers around and i asked my mother to buy a kit and help me do it and we did it. vanessa it was my idea . . . i felt really excited about it like “finally, i’m in some kind of club,” i don’t have to wash my natural hair and have it shrink so it was really an exciting experience. i guess i was walking a little bit taller the next day at school. nicole i was about four or five years old and . . . my mom was combing my hair and it was tough because you know natural hair, i was getting my hair pulled every time and i would cry and cry. . . . so, every morning i remem- ber dreading getting my hair pulled. so, my mom actually said to me one time . . . there’s this treatment you can do and your hair will be a lot easier to comb so it won’t hurt as much . . . i’ve pretty much had my hair relaxed since then. sheneneh jenkins was a female character played by african-american actor martin lawrence on the television sitcom martin, which ran from to . byrd and tharps further write, “most consumers assumed that african pride came from a black manufacturer until company president brian marks decided to sue a smaller black-owned company and his cover was blown” ( ). black women, beauty, and hair as a matter of being jackie the first relaxer must have been in grade six, and i think my mom was just tired of combing my hair and tired of me screaming but then i think my mom relaxed it at home and of course that didn’t last and my hair broke off a lot. rebecca when i was in my second year of university . . . when i went to the hair- dressers . . . i just fell in love because it was something that i could relate to because it was women in particular like me and . . . i wanted to do what they were doing. . . . my hairdresser and i started talking about having straight hair and she said well the only way to straighten it is to put a chem- ical in it and she kept saying how wonderful it would look and i was . . . fasci- nated. part of me was totally thrilled to be a part of something that i could identify with and so i did it. tracy my mom used to press my hair for years and she didn’t want me to relax my hair because she never relaxed her hair. . . . everyone reacts differently to relaxers and there are different types of relaxers too. . . . the chemicals are ridiculous and now i think it’s just crap that you put in your hair. at the time, i just kept thinking to grin and bare it because it will be straight and i can sweat and it will still be straight. these black women talk about using relaxers in a way that suggests it was something they willingly did to their hair in order to be a part of something; in other words, participation in straightening signified a collective sense of black pride. similarly, as lanita jacobs-huey found with respect to african-american women, in their talk about hair and hairstyles, they “strategically invoke an array of in-group hair terms, gendered experiences, and cultural discourse styles to establish their individual and collective rights” ( ). however, it is important to consider cornel west’s assertion that “much of black self-hatred and self- contempt has to do with the refusal of many black americans to love their own black bodies—especially their black noses, hips, lips, and hair” ( ). physical attractiveness and sexuality: is hair really depoliticized? all women, irrespective of race, compare themselves to the western beauty ideal. as patton notes, “it is fair to say that in the united cheryl thompson states, and in many countries that are influenced by the united states (largely through mediated forms), the current standard of beauty is a white, young, slim, tall, and upper class woman” ( ). however, shame is a key concept that underscores in-group talk about black hair. according to eve sedgwick the power of shame lies in its ability to transform or intensify the meaning of things such as body parts, identities, or people’s behavior towards one- self ( – ). in describing the shame one of her respondents experienced, tate writes, “it is about how black others perceive and react to her and it is felt because she has an attachment to black community” ( ). because shame is a part of the process in which identity is formed and is available for the work of refram- ing, transfiguration and deformation of identities (tate ), if “beauty contradictions are felt as shame and ambivalence because the essentialisms of racialized and normalized racializing beauty mean that black beauty is entailed, made proper, installed as such and naturalized within our thoughts and our being” (tate ), and identification is a matter of emulating a fake aesthetic, while disidentification is a matter of embodying an authentic black beauty, is hair really depoliticized? sheila, like millions of other black women, has taken to wearing synthetic hair weaves, a process she describes as follows: i just glue in tracks up until not the top of my head but more or less to the top it just looks very natural. there’s not one person that can tell my hair is weave. but you can still see my scalp and everything at the very front so when i part it, it looks like it just blends right in which is why i only do a half head so it still looks natural. . . . so you leave it like an inch so if you want to wear your hair back you can pull it back and not see the tracks and still only see your natural hair. these comment are quite revealing in that despite the fact that sheila continues to relax her hair in addition to weaving, her interpretation of her relaxed hair as “natural”—by its very nature an inauthentic black style—illustrates how the authentic natural black aesthetic is often denied the right to exist; instead it is replaced (almost entirely) by the “regulatory ideal of normalized racializing black beauty congealed into a corporeal . . . and also a psychic reality” (tate ). for example, sheila continues, “my tracks are rows of synthetic or fake hair. black women, beauty, and hair as a matter of being hair is relaxed so the hair is straight. it’s just normal black straight hair. i mean, it’s not caucasian, it’s the permed straight so it still kind of has that texture to it.” how did black hair get to a point where straight hair is considered to be “normal?” importantly, vanessa said, “i definitely see it as a lack of edu- cation, a lot of the black magazines i read like essence and ebony all the ads in there are for relaxed hair.” from oprah to janet jackson to tyra banks and a slew of others, weaves have become a normative part of black beauty. more so than ever before, black women are bombarded with images that have normalized long, straight hair. while the age long quest was always to have straight hair “through the use of weaves, the long-standing black problem of not having long hair is effectively solved” (byrd and tharps ), but why has this obsession with having long— unnaturally black—hair taken off with such force? as hooks reminds us, “popular culture provides countless examples of black female appropriation and exploitation of ‘negative stereo- types’ to either assert control over the representation or at least reap the benefits of it” (black looks ). undoubtedly, the image of black beauty in popular black magazines gives the impression that black hair is only beautiful when it is altered. the vast majority of the images in publications such as essence, ebony, and sophisticates black hair styles and care guide, are of women with straight, long hair, and to the extent that they do show natural hairstyles, it is often an insert with hairdos that arguably perpetu- ate a racialized black beauty. with the exception of sheila, each of the women i spoke to about weaves affirmed hooks’ argument that “the idea that there is no meaningful connection between black experience and criti- cal thinking about aesthetics or culture must be continually inter- rogated” (yearning ). for vanessa, nicole, rebecca, tracy, and christine, resisting ascribed beauty ideals serve to counterpoliti- cize the signifier of ethnic and racial devalorization and challenge definitions of blackness as defined by hegemonic structures: vanessa it just seems like we have to conform to some standard that’s out there. why should we feel that way? i’m a black woman, my hair is never going to be long down to my butt, i’m not mixed with anything . . . we don’t grow hair naturally that long, i don’t see what the appeal is to have silky long hair and it is so obviously fake. cheryl thompson nicole i think growing up and always kind of being “the other” and seeing white cul- ture for what it is, it’s always been inherently fake. . . . the [white] women have always been very insecure or very focused on their appearance and so you know i don’t like my hair like this, i want to perm it. . . . it’s all a business and most people are not happy with what they have naturally. rebecca i have mixed feelings about it [weaves]. i have mixed feelings because i understand the history and i understand the struggle of identity. . . . i’m conflicted because it’s fake. it’s again something being projected by a mass media and a power outlet. . . . i think that you lose something of your identity if you’re doing that to yourself. tracy i think the whole process of weaving is damaging to your hair. . . . i just think it’s the worst thing we can do psychologically and physically to our- selves. psychologically to ourselves and physically to our hair. . . . there is no way you can do something like that long term and your hair is going to be thick and healthy, there’s just no way. it’s like anything else—chemicals, relaxing, and after a period of time hair braiding—anything you add to your hair like that will deteriorate it. christine people are buying into this standard; this beauty standard that we’re well aware of because even back in the th century it was a problem. when we deny this standard and we wear our hair natural . . . we’re saying you know what, i’m beautiful the way i am, i’m not going to try to be like you. and when you weave, what you’re saying to the world is that i want to imitate you . . . i don’t like who i am naturally. it is my contention that although hair straightening, weaving (and to some extent braid extensions) are as christine noted, “tantamount to torture,” black women continue this practice because a “real” woman has long straight hair, while short nappy hair is relegated to something children have or those women— according to mainstream and black beauty standards—who may be deemed less attractive. what affect does a valorized inauthentic aesthetic have on a black woman’s conceptualization of her phys- ical attractiveness and sexuality? there are of course exceptions to this statement. for example, sudanese supermodel alex wek and actor whoppi goldberg both adorn natural hairstyles and it has not impeded their ability to be successful in mainstream culture. black women, beauty, and hair as a matter of being the crux of the hair issue for black women appears to center on the performance of beauty and to a large extent, heterosexual courtship. latoya said, “i feel that men have such a strong attac- ment to what it means to be feminine and female that they’ve created this expectation that to be a woman, to be considered sexy, to be attractive and desirable one must have a head of long flowing hair and to choose to do something different with hair is like a slap in the face and a personal offence to them.” latoya’s comments are illustrative of butler’s argument that gender is culturally constructed. the notion that gender is constructed sug- gests a “certain determinism of gender meanings inscribed on anatomically differentiated bodies” ( ) wherein the body is “a construction, as are the myriad of ‘bodies’ that constitute the domain of gendered subjects. bodies cannot be said to have a signifiable existence prior to the mark of their gender” ( ). for instance, patton notes that “we learn that beauty is one of the defining characteristics of a woman. . . . most often the hair com- mercials show euro american women tossing their bouncy, shiny, long, straight hair. . . . this image, while directed toward euro american women, impacts african american women, because it is often not our image that becomes the vision and standard of beauty” ( ). to what extent does the body come into being in and through the mark(s) of gender? for black women, gender (and sexuality) comes into being through adherence to an inau- thentic hair standard. as mcdowell affirms, “deep down, we might even believe that we must be in a perpetual state of artificial fine- ness to attract men. . . . to get a man, i need to beautify myself by any means necessary—including starving and having my power/ telephone/hot water shut off—in favour of phat hairstyles” ( ). we are socially constructed through the language of texts and through mediated images to believe that hair is what makes a female (sex) a woman (gender), and a beautiful woman is defined by hair that is long, silky, and flowing. for example, in big hair: a journey into the transformation of self, grant mccracken describes a variety of hairstyles for women; he suggests that each style carries a variety of meanings: slang for great or wonderful. for example, previously noted works of collison and persadsingh. cheryl thompson “voluptuous hair” is mostly about sexuality. “imperial hair” is mostly about social standing. the “career coif” is mostly about professionalism. the “shaved and shorn” look is mostly about protest. the “pixie” look is about a certain charm and élan. the “mature bob” is about a certain tragic or dignified retreat from fashion. each look is a piece of our culture turned into the nature of hair. ( – ) where does that leave black women if, for the most part, each of the aforementioned hairstyles are naturally unattainable, short of getting a weave to “fix” the problem? importantly, “femininity is not merely associated with long hair . . . but with white women” (banks ). thus, just like during slavery where “emulating white hairstyles, particularly straight hair, signified many things in the black community . . . free vs. slave; employed vs. unemployed; educated vs. uneducated; upper class vs. poor” (patton ), arguably, the status of black liberation remains perpetually stagnant because the imitation and emulation of white-defined standards of beauty continue to reign supreme. while “self-hate” is a term that many black women resist using because of its harshness, vanessa reminds us that whether or not a black woman identifies her hair alternation as an act of “self- hatred,” there is still an attempt being made to emulate whiteness: vanessa the whole european look is also exotic to men. i don’t remember where i heard it but some female artist was . . . perming her hair and she found that boyfriends were leaving her for the more european look so she started weav- ing her hair and dying it blonde or light brown . . . to try and fit in. further, jackie, rebecca, latoya, and tracy show us how female (hetero) sexuality is perpetually defined by long flowing hair: jackie when you feel like you can attract a man that gives you some power. . . . back in the day in europe if you didn’t have the long thick flowing hair you were probably suffering from malnutrition or something. . . . i think it’s just sexuality that you’re seeing . . . if you see a couple of short haired women, you automatically assume that they’re lesbian. rebecca when i was younger, everybody thought i was a boy before i developed . . . and this whole thing again about being sexualized and being put into a black women, beauty, and hair as a matter of being gender that i didn’t identify with . . . in high school i became very dainty and very girlish and all those things which are me you know wearing the dresses and wearing very elegant clothing which i love and is part of my femininity but when my hair is cut short some people are like is she gay or is she bi? latoya hair is like this market for heterosexuality and femininity. . . . i’ve had guy friends who have clearly said to me that what they like is long flowing hair. . . . i’m finding that i’m getting more favourable responses from men with fake hair in my head than i did when i had my natural hair and i was wearing it how it grows out of my head. tracy when my hair was short i was wearing a lot of makeup. i always had make up and jewellery and earrings . . . i wore a lot of skirts and then my hair started growing and i just felt better. . . . you do kind of feel a little mascu- line but i don’t know if masculine is the right word, maybe a little less feminine is a better way of saying it. as butler declares, “women who fail to . . . understand their sexu- ality as partially constructed within the terms of the phallic econ- omy are potentially written off within the terms of that theory as ‘male-identified’ or ‘unenlightened’” ( – ). if black beauty is about repeating hegemonic norms in order to be a viable subject, does that mean that challenging a racialized black beauty and a reified white beauty is futile? black hair is (not) just hair it is not enough for black women to simply wear their hair any way they please without their styling choice being called into question. after centuries of condemnation, black hair is inex- tricably laden with social, class, sexual, and cultural implica- tions. for example, i asked each of the women to describe what it means to have “good hair” and “bad hair,” tracy, latoya, rebecca, and nicole’s responses suggested a shared understanding of the power associated with adhering to the western (white) beauty standard—having hair that is straight, long, and flowing—in addition to lighter skin, and called into question the assertion that all hair is “good”: cheryl thompson tracy to me, good hair means less nappy and bad hair means negroid and i think that’s just the extreme continuum. . . . the closer to caucasian hair your hair is . . . is good hair, the further away from that on the oppo- site end of the continuum towards being . . . black, thick, nappy, dense strong hair is bad hair. latoya when i think of good hair it goes beyond the hair and it speaks more to the person. so people with good hair also look a certain way. for the most part, their skin is lighter; they might even be prettier or considered to be prettier. rebecca in terms of “mixed race” children . . . it doesn’t speak to their identity; it speaks to their identity but it doesn’t in a positive way speak to the tradi- tions of african hair, it sort of adds a negative tone onto it. nicole i’ve heard that i had good hair growing up. good hair now to me is when you have good strong, thick and healthy hair but it was also you know how soft your hair was, the longer your hair was, i guess maybe closer to white- ness in texture or the finer your hair was, was considered to be good hair. rose weitz argues that “no matter what a woman does or doesn’t do with her hair—dyeing or not dyeing, curling or not curling, covering with a bandana or leaving uncovered—her hair will affect how others respond to her, and her power will increase or decrease accordingly” ( ). as mcdowell notes, “those making the choice to be ‘happy nappy’ are in the minority. . . . many with natural hairstyles can recall shameful childhood memories as well as recent ones of feeling too nappy by nature. they often face criticism of being unrefined, unhygienic, low class and ugly. alternatively, they are accused of being militant, lesbian or out of touch with the times” ( ). even though various texts have argued that natural hairstyles (e.g., dreadlocks and afro styles) were once politicized statements of pride but are now incorpo- rated into mainstream fashions—and therefore are depoliticized— a fact that needs to be underscored is that black women continue to fear adorning the “natural,” especially in the workplace because of the spectacle an authentically black aesthetic will create, and the potential negative impact on one’s economic mobility. black women, beauty, and hair as a matter of being while there is anti-discrimination legislation in western countries, and hair choices are an important mode of self- expression, as caldwell astutely notes, “for blacks, and particu- larly for black women, such choices also reflect the search for a survival mechanism in a culture where social, political and economic choices of racialized individuals and groups are con- ditioned by the extent to which their physical characteristics, both mutable and immutable, approximate those of the domi- nant racial group” ( ). for instance, jackie said of her work- place, “the only black girls who are wearing their hair natural are the ones who are mixed so going for the natural kind of curl but for the most part they all have their hair straightened; there’s a handful of us with our braids not too many of us with braids, and a lot of them with weaves,” and vanessa said, “if i decided to grow an afro and i went to work people would be like ‘what’s up with her, what’s she trying to prove?’. . . if i were to go to work with all . . . white men, they might think i was trying to prove something and they would distance them- selves because they’d think i was some kind of radical.” these women affirm that very little has changed with respect to the depoliticization of black hair moreover “the rationalizations that accompanied opposition to afro hairstyles in the s— extreme, too unusual, not businesslike, inconsistent with a conservative image, unprofessional, inappropriate with busi- ness attire, too ‘black’ (e.g. too militant), unclean—are used today to justify the categorical exclusion” (caldwell – ) of natural hairstyles in the workplace. for example, jackie, tracy, and latoya rationalize about wearing natural hairstyles (afros and dreadlocks) to work: jackie one day when i’m more established in my career i would like to get dread- locks . . . i can’t do it now . . . i want to be in corporate canada and . . . if i’m going to show up with my hair in dreadlocks in the first year of dreadlocks [when they are very short] they would not think i fit a corporate ideal and for sure i wouldn’t get the job. tracy i was working in the office and i went in there with dreads and i thought they were going to fire me and they would tell me it was because of my performance but i’d know it was because of my hair. i was so fearful. cheryl thompson latoya i feel that there’s still in canada definitely there’s still a lot of focus that’s put on black people in general about how they look in the professional landscape and if you don’t look a certain way and you don’t speak a cer- tain way your opportunities career wise just do not present themselves. further, tracy said, “if i went in (to work) with a huge afro tomorrow that’s political because they’ll think, ‘ok, what’s my statement now?’” ultimately, the crisis of black womanhood can only be addressed as hooks poignantly writes, “by the development of resistance struggles that emphasize the importance of decoloniz- ing our minds, developing critical consciousness” (black looks ). while resistance can take the form of momentous acts of orga- nized, planned, and disciplined protests, “it may consist of small, everyday actions of seeming insignificance that can nevertheless validate the actor’s sense of dignity and worth” (caldwell ). conclusion i got tired of perming my hair and using all those chemicals on my head. . . . straightening my hair was a way of conforming to caucasian society, and that’s just not my tribe . . . i finally came to a place where i could permit my hair to be natural.—hazelle goodman, actress and writer it has been the intent of this article to refute the notion that black women are liberated from their hair. today, it is not uncommon to hear someone flippantly remark, “just get a weave, it’s no big deal” without a second thought. covering up your nat- ural tress and damaging your real hair for the sake of a desired “look” should not be taken lightly. sure, all women, irrespective of race, have been socialized to adhere to a beauty standard that has caused “psychological damage, loss of self-esteem, anorexia, bulimia, sexism, racism, ignorance, and lack of communication” (patton ); however, black women are unique in that we are asked not just to strive to attain mainstream standards of beauty, but to have such standards completely override our natural being. as byrd and tharps sullenly conclude, “america’s, including black america’s, beauty ideal has not altered drastically since the late s. large breast, small waists, and masses of flowing hair mastalia and pagano, . black women, beauty, and hair as a matter of being are still the look desired by men and sought after by many women. . . . black people looking to fit into the mainstream visu- ally still overwhelmingly have to contend with the same standards as in the past” ( – ). it is the st century, yet black women are still struggling to meet this standard. ontologically speaking, these eight women have shown us that black subjectivity has no existence without comparison to white (mainstream) culture. natural black hair remains misunderstood, villainized, and eroti- cized in virtually every facet of society. it is not simply a matter of assuming that black women who relax, weave or braid their hair do not want to, or have not considered going natural, but fear of societal reprisal—i.e., limited employment opportunities; lack of male interest (courtship); and, the possibility of their sexuality being questioned—is the overwhelming reason why hair contin- ues to hold such immense political power. as film producer max- ine walters asserts, “in america, blackness doesn’t count. society is not geared toward giving us confidence—it’s geared toward keeping us in our place” (qtd. in mastalia and pagano ). until black women (including “mixed race” women, who may not nec- essarily process or weave their natural hair) collectively agree that hair alternation stunts any potential to overcome the legacy of sla- very and a multi-generational pathology of self-hatred, hair will always be a contentious (and debated) issue. works cited banks, ingrid. hair matters: beauty, power, and black woman’s consciousness. new york: new york u p, . butler, judith. gender trouble. great britain: routledge, . byrd, ayana d., and lori l. tharps. hair story: untangling the roots of black hair in america. new york: st. martin’s p, . caldwell, paulette. “a hair piece: perspectives on the intersections of race and gender.” duke law journal ( ): – . collison, michele n.-k. it’s all good hair: the guide to grooming black children’s hair. new york: harpercollins, . evans, peggy c., and allen r. mcconnell. “do racial minorities respond in the same way to mainstream beauty standards? social comparison processes in asian, black, and white women.” self and identity ( ): – . festinger, leon. “a theory of social comparison processes.” human relations ( ): – . hooks, bell. yearning: race, gender, cultural politics. toronto: between the lines, . cheryl thompson hooks, bell. black looks: race and representation. toronto: between the lines, . jacobs-huey, lanita. from the kitchen to the parlor: language and becoming in african american women’s hair care. new york: oxford u p, . jones, charisse, and kumea shorter-gooden. shifting: the double lives of black women in america. new york: harpercollins publishers, . law, cheryl, and magdala p. labre. “cultural standards of attractiveness: a thirty-year look at changes in male images in magazines.” j&mc quarterly . ( ): – . mastalia, francesco, and alfonse pagano. dreads. new york: artisan, . mccracken, grant. big hair: a journey into the transformation of self. toronto: penguin books, . mcdowell, akkida. “the art of the ponytail.” body outlaws: young women write about body image and identity. ed. ophira edut. seattle: seal press, . – . mercer, kobena. welcome to the jungle: new positions in black cultural studies. new york: routledge, . morrow, willie. years without a comb. san diego: black publishers of san diego, . patton, tracy o. “‘hey girl, am i more than my hair?’ african american women and their struggles with beauty, body image, and hair.” nwsa journal . ( ): – . persadsingh, neil. the hair in black women. jamaica: stephenson’s litho press, . robinson, lori. “the politics of hair.” the crisis sept.–oct. : . rooks, noliwe. hair raising: beauty, culture, and african american women. new brunswick: rutgers u p, . sedgwick, kosofsky e. “queer performativity: henry james’s the art of the novel.” glq . ( ): – . tate, shirley. “black beauty: shade, hair and anti-racist aesthetics.” ethnic and racial studies . ( ): – . taylor, paul c. “malcolm’s conk and danto’s colors; or four logical peti- tions concerning race, beauty, and aesthetics.” african american literary theory: a reader. ed. winston napier. new york: new york university press, . – . thornton, bill, and scott moore. “physical attractiveness contrast effect: implica- tions of self-esteem and evaluations of the social self.” psychology of personality and social psychology . ( ): – . weitz, rose. “women and their hair: seeking power through resistance and accommodation.” gender & society . ( ): – . west, cornel. race matters. boston: beacon press, . interest and beauty in the world environmental conservation grows exponentially with such loss. for similar reasons, we should have taken better care of the biosphere's rivets, the living species. their future, in turn, is determined inter alia by their genetic diversity, so that neglect of this point may shake the very foundation of the biosphere and hence of our human existence. gabor vida, professor and head* department of genetics eotvos lorand university museum korut a budapest hungary. * and, incidentally, the co-organizer and local agent of our fourth international conference on environmental future: surviving with the biosphere, which is to take place during - april mainly on the heights overlooking budapest, and concerning which we plan to publish details in our next issue. —ed. editorial comment interest and beauty in the world t o one who, for nearly years, has found our natural world fascinating and beautiful, it has become moreand more distressing and emotionally painful to see it made increasingly and often shockingly homo- genized and drab. the incredible diversity that makes nature so interesting and satisfying to observe and investigate is disappearing at an exponentially increasing rate. the beauty that makes life so pleasant and worth living fades almost daily before our eyes, mainly in the names of'progress' and profit! the only factor that will make the situation of our descendants tolerable may be that they will never have experienced the beauty that we know. if some of what is written about it persists and is read, or if photographs and paintings manage to survive and save faded inklings of what we have been privileged to enjoy, and so are seen, posterity will justly condemn us. the results of our greed and short-sightedness will be what will live after us. our great-grandchildren will have little reason to revere us. there will surely be little trace of ancestor-worship in a future and, hopefully, more enlightened world. one wonders why a natural landscape never becomes tiresome, why a new view—whether of mountain or prairie—is such a delight, why one never sees clashing or disharmonious colour combinations in a flower, a sunset, or a landscape. is this something inherent in these phenomena, or is it something within us? why is it that such things are so vivid to us when we are small children but tend to relative dullness as we mature? the latter impression may be the result of familiarity coupled with increasing preoccupation with survival in an ever-more crowded and competitive world. but our original response to what we see in nature must be ingrained—an age-long, innate evolutionary conditioning and response to the environment in which man developed. instinctive recognition of what we were surrounded by during the evolution of our consciousness may be what makes us comfortable in, and responsive to, natural beauty. this beauty, itself, may be what, during our evolution, was imprinted in our nervous systems. the clash and discordance of so much of what our artificial surroundings confront us with—colours put together in strange combinations, proportions seldom or never seen in nature, weird angular shapes and geometrical arrangements—may well be simply things that were uncommon or not present in our evolu- tionary environment. natural selection has formed us to fit and respond to what we are surrounded by. artificial selection, resulting from more and more crowding into these increasingly unnatural surroundings, may well, as time goes on—if we survive—change us, even making us insensitive to what now pleases and satisfies us. it may make us, in the not-too-remote future, into something not very admirable from our present viewpoint. at present it seems to us that, if there is something particularly beautiful or interesting in the world, there is always someone ready and waiting, for profit or power, to destroy or anyway change it—a jaundiced view, you may say, but one which we have become increasingly forced to adopt. f. raymond fosberg, botanist emeritus national museum of natural history smithsonian institution washington dc , usa. https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core [pdf] the “beauty arch: ” a new aesthetic analysis for malar augmentation planning | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /scs. corpus id: the “beauty arch: ” a new aesthetic analysis for malar augmentation planning @article{marianetti thea, title={the “beauty arch: ” a new aesthetic analysis for malar augmentation planning}, author={t. marianetti and s. cozzolino and a. torroni and g. gasparini and s. pelo}, journal={journal of craniofacial surgery}, year={ }, volume={ }, pages={ – } } t. marianetti, s. cozzolino, + authors s. pelo published medicine journal of craniofacial surgery midface is a critical area for the aesthetics of the face. [...] key method we took a reference group of italian women participating in a national beauty contest in on which we performed our analysis. we used the ideal values to elaborate the surgical treatment planning of a second group of consecutive female patients affected by skeletal class iii malocclusion.twenty-three patients undergo simultaneous le fort i osteotomy and malar implants. from the descriptive statistical comparison of the…expand view on wolters kluwer aicef-chirurgiaplasticafacciale.it save to library create alert cite launch research feed share this paper citationsbackground citations view all topics from this paper zygomatic bone malocclusion esthetics (discipline) name aspartate transaminase description malar flattening absorbable implants citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency modified high-level le fort i advancement without malar augmentation: assessment of effect on midfacial aesthetics. a. Özel, z. Ç. yılmaz, r. sağlam, s. uçkan medicine international journal of oral and maxillofacial surgery save alert research feed surgical adjuncts to rhinoplasty: an algorithmic approach john r peleman, m. chung, + authors h. vásconez medicine aesthetic plastic surgery view excerpt, cites background save alert research feed early assessment of computer-assisted malarplasty: a novel methodology for both reduction and augmentation s. o. keyhan, h. fallahi, a. azari, behzad cheshmi computer science save alert research feed quantification of the aesthetically desirable female midface position gary linkov, pooja mally, c. czyz, a. wulc medicine aesthetic surgery journal pdf save alert research feed evaluation of the relationship between malar projection and lower facial convexity in terms of perceived attractiveness in -dimensional reconstructed images hon kwan woo, deepal haresh ajmera, + authors m. gu medicine head & face medicine view excerpts, cites background save alert research feed customized approach to facial enhancement. ava t shamban medicine facial plastic surgery clinics of north america save alert research feed rhinoplasty combined with centrofacial lipofilling to optimize facial proportions m. carvas, p. tonnard, a. verpaele medicine aesthetic surgery journal. open forum pdf save alert research feed references showing - of references sort byrelevance most influenced papers recency aesthetic augmentation of the malar‐midface structures l. whitaker medicine plastic and reconstructive surgery save alert research feed augmentation of cheek bone contour using malar osteotomy w. layoun, l. guyot, o. richard, r. gola medicine aesthetic plastic surgery save alert research feed malar augmentation: a -year retrospective review of the silastic midfacial malar implant. s. metzinger, e. mccollough, j. campbell, d. rousso medicine archives of otolaryngology--head & neck surgery pdf save alert research feed gridplan midfacial analysis for alloplastic implants at the time of jaw surgery p. nocini, a. boccieri, d. bertossi medicine plastic and reconstructive surgery save alert research feed simultaneous malaroplasty with porous polyethylene implants and orthognathic surgery for correction of malar deficiency. m. robiony, f. costa, v. demitri, m. politi medicine journal of oral and maxillofacial surgery : official journal of the american association of oral and maxillofacial surgeons view excerpt, references background save alert research feed malar augmentation using lamellar split osteotomy k. salyer medicine the journal of craniofacial surgery save alert research feed advancement of the midface, from conventional le fort iii osteotomy to le fort iii distraction: review of the literature. e. nout, l. cesteleyn, k. v. d. van der wal, l. v. van adrichem, i. mathijssen, e. wolvius medicine international journal of oral and maxillofacial surgery pdf save alert research feed zygomatic sagittal split osteotomy: a novel and simple surgical technique for use in midface corrections g. gasparini, g. saponaro, a. moro, r. boniello, d. cervelli, s. pelo medicine the journal of craniofacial surgery save alert research feed alloplastic cheek augmentation. r. mladick medicine clinics in plastic surgery view excerpt, references methods save alert research feed a lateral photometric analysis for aesthetic-orthognathic treatment. k. bütow medicine journal of maxillofacial surgery save alert research feed ... ... related papers abstract topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue a mathematical analysis of the sleeping beauty problem by jeffrey s. rosenthal* (august ; revised march .) . introduction. the sleeping beauty problem (elga, ; see also piccione and rubinstein, ) is a philosophical dilemma related to conditional probability. it may be succinctly described as follows. sleeping beauty is put to sleep, and a fair coin (say, a nickel) is tossed. if the nickel shows heads, then beauty is interviewed on monday only, while if the nickel shows tails, beauty is interviewed on both monday and tuesday (and given an amnesia-inducing drug between the two interviews, so she does not remember the first interview during the second). in each interview, without access to any additional information (such as the result of the coin toss, or the existence of any previous interviews, or the day of the week), beauty is briefly woken and is asked to assess the probability that the nickel showed heads. the question is, what probability should she assign to this? one possible answer (e.g. lewis, ; arntzenius, ; bostrom, ; pust, ) is / . after all, the coin is fair, so beauty surely would assess the probability of heads as / before being put to sleep. now, when beauty is awakened and interviewed, she apparently does not gain any new information, since she knew in advance that she would be interviewed at least once no matter what. so, if the probability of heads was / before, it seems plausible that this probability should be unchanged during the interview, giving a final answer of / . this answer seems rather intuitive (and was, in fact, the author’s first reaction upon hearing of this problem). but is it correct? another possible answer (e.g. elga, ; dorr, ; monton, ; weintraub, ; horgan, ; neal, ; titelbaum, ) is / . one argument for this is that beauty will be interviewed twice as often when the nickel shows tails as when it shows heads. thus, if during each interview she makes a bet in which she will win $ on tails but lose $ on *department of statistics, university of toronto, st. george street, room , toronto, ontario, canada m s g . email: jeff@math.toronto.edu. web: http://probability.ca/jeff/ heads, then she will break even on average (and also, by the law of large numbers, break even over the long run if the experiment is repeated many times). but for this to be a fair bet, the probability of heads must be / . this argument is somewhat convincing. however, one concern is that it does not appear to make explicit use of the amnesia aspect, i.e. it appears to still apply if we instead assume that beauty is permitted to remember any previous interviews. but under that assumption, the conclusion seems incorrect, since if beauty remembers having a previous interview, she then would immediately know that the nickel was tails with probability . some authors have accepted certain parts of both of these solutions. for example, al- though arntzenius ( ) argues that beauty should assign probability / to heads, he nevertheless agrees that “if she bets according to her degree of belief of / , she can be expected to lose money against a bookie, and she and the bookie know this in advance”. in other words, he feels that the question of beauty’s assigned probabilities is distinct from the question of fair betting odds, the former being / and the latter being / . a different approach is to appeal to the principle of indifference, which asserts that equal probabilities should be assigned to any collection of indistinguishable, mutually exclusive and exhaustive events. but in this case, it is not clear to what “collection” this principle should be applied. if we apply it to “nickel heads” and “nickel tails”, we obtain an answer of / . if we apply it to “nickel heads and interview monday”, “nickel tails and interview monday”, and “nickel tails and interview tuesday”, we obtain an answer of / . if we apply it to “interview monday” and “interview tuesday” we conclude that with probability / the interview will be on monday, and then a second application implies that the probability of heads is ( / )( / ) = / . in short, the principle of indifference does not appear to resolve the problem satisfactorily. to a mathematical probability theorist such as myself, such controversy is frustrating. we are being asked to compute the conditional probability that the nickel showed heads, conditional on the fact that beauty is currently being interviewed. conditional probabilities are well understood and should be unambiguously analysable by straightforward mathemat- ics, using the classic formula p (a |b) = p (a and b) p (b) . so, how could this simple conditional probability problem create such controversy? the difficulty seems to be that a precise mathematical interpretation of “conditional on currently being interviewed” is unclear, thus creating an obstacle to direct mathematical calculation. this paper attempts to reconsider the problem in such a way that precise mathematical reasoning can then be applied. after such reconsideration, we then obtain the answer / through direct calculation. it is hoped that this mathematical approach avoids most of the philosophical ambiguities inherent in some previous arguments. . a subproblem: the sleeping peon. consider the following simple subproblem. we find a peon and put him to sleep, and then flip a fair coin, say a nickel. if the nickel shows tails, we wake peon and interview him (just once), asking him to assess the probability that the nickel showed heads. if the nickel shows heads, then we flip a second fair coin, say a dime. if the dime shows tails, we similarly wake the peon and interview him once. if not (i.e., if the nickel and dime both show heads), then we do not bother to wake or interview peon at all. in summary, we interview peon once if either the nickel or the dime show tails, otherwise we interview him zero times. hence, the overall probability that peon is interviewed is equal to / . under these circumstances, what probability should peon assign, upon being interviewed, to the event that the nickel showed heads? for this subproblem, the solution seems clear. let interviewed be the event that “peon was interviewed (at all)”, and let nickelheads be the event “the nickel showed heads”, and similarly dimeheads, etc. then peon is being asked to assess the probability of nickelheads, conditional on knowing only that the event interviewed occurred. indeed, since this sub- problem involves no amnesia or multiple interviews, all that peon learns is whether or not he is interviewed at all, i.e. whether or not the event interviewed occurs, so it is mathematically clear that interviewed is the event peon should condition on. that is, peon is being asked to compute the conditional probability p (nickelheads |interviewed). he would do so as follows: p (nickelheads |interviewed) = p (nickelheads and interviewed) p (interviewed) = p (nickelheads and dimetails) p (nickeltails or dimetails) = / / = / . thus, for this simple subproblem, the correct probability that peon should assign during the interview to the event that the nickel showed heads is equal to / . i consider this answer to be correct and clear and unambiguous, following directly from straightforward mathematical laws of conditional probability. i shall now argue that the original sleeping beauty problem can essentially be reduced to this simple peon subproblem. . the original problem revisited. to make use of the above peon subproblem in analysing the original sleeping beauty problem, we add one additional element. we assume that in addition to the previous elements (the nickel, sleeping beauty herself, the amnesia-inducing drug, etc.), we also have at our disposal another fair coin, say a dime. we make use of the dime as follows. if the nickel showed tails, then the dime is simply placed so that it shows heads during beauty’s monday interview, and then repositioned so that it shows tails during beauty’s tuesday interview. if instead the nickel showed heads (so beauty will only be interviewed once), then the dime is instead simply flipped once in the usual fashion at the beginning of the experiment, and allowed to show its actual flipped result (either heads or tails, with probability / each) during the one interview that will take place on monday. furthermore, we assume that beauty is not allowed to see the dime at all, and might not even know of its existence. thus, the dime does not in any way affect or control or interfere with any aspect of the original problem. however, we shall see that the dime does permit a precise mathematical analysis of the problem. we now reason as follows. call an interview a “heads-interview” if it takes place while the dime shows heads. if the nickel showed tails, then there will certainly be precisely one heads-interview. if the nickel showed heads, then there will be either one or zero head- interviews, with probability / each. so, the number of heads-interviews behaves just like the total number of interviews in the peon subproblem. now, if beauty were told just before her interview that the dime shows heads (while still undergoing complete amnesia regarding any previous interviews), then she would learn that a heads-interview did indeed occur. this would then put her in precisely the same situation as that of the peon in the subproblem above. hence, just like the peon, beauty would then assign probability / that the nickel showed heads. in summary, if beauty were told that the dime showed heads, then the correct answer to the problem would be / . similarly, if beauty is informed (just before her interview) that the dime shows tails, then by identical reasoning, the answer would again be / . in summary, the answer would be / if beauty could see the dime, regardless of whether the dime was currently showing heads or tails. we can write this in mathematical terms as p (nickelheads |dimeheads) = p (nickelheads |dimetails) = / . where now dimeheads is the event that the dime shows heads during the particular interview under consideration, i.e. that the interview was a heads-interview (and similarly dimetails). in the actual problem, we assume that beauty cannot see the dime. however, we now argue that, as far as probabilities for the nickel are concerned, that fact is irrelevant, and beauty should still assign the probability / even if she does not know what the dime shows. to see this, write p (nickelheads) for the overall probability that beauty should assign to the event that the nickel showed heads upon being interviewed (but now without knowing about the dime). then it follows by the law of total probability that p (nickelheads) = p (dimeheads) p (nickelheads |dimeheads) + p (dimetails) p (nickelheads |dimetails) = p (dimeheads) ( / ) + p (dimetails) ( / ) = / , since p (dimeheads) + p (dimetails) = . thus, the answer for this version of the problem seems unambiguously and mathemati- cally to be / . and, since the mere existence of the dime (which beauty cannot see and has no knowledge of) cannot change beauty’s probabilities, i submit that this argument shows unambiguously that the answer to the original sleeping beauty problem is also / . . some related issues. while the above completes my main argument, i now consider a few other related issues. . . a slight variant: randomised sleeping beauty. consider a very slight variant of the original sleeping beauty problem. as before, if the nickel is tails we will interview beauty twice, once on monday and once on tuesday (with amnesia). and, as before, if the nickel is heads we will interview beauty just once. the only modification is that if the nickel is heads, then rather than necessarily interviewing beauty on monday, we will first flip another fair coin (say, a dime), and then conduct our (one) interview on monday if the dime is heads, or on tuesday if the dime is tails. (we assume, as usual, that sleeping beauty cannot tell what day it is.) for this variant, if beauty were told that her interview was taking place on monday, then this would reduce precisely to the peon subproblem above. that is, as far as monday interviews go, if the nickel showed tails then she would certainly have precisely one, while if the nickel showed heads then she would have one only with probability / (i.e., only if the dime showed tails), otherwise zero. furthermore, the fact that the interview is actually taking place on monday tells her that she did indeed have one monday interview. thus, beauty is in precisely the same situation as the peon in the above subproblem. so, just as in the subproblem, the correct answer for the probability that the nickel showed heads would be / . similarly, if beauty were told that her interview was taking place on tuesday, the answer would again be / . (the reasoning is identical to the above, except that the roles of “heads” and “tails” for the dime are interchanged.) in summary, the answer would be / if she knew which day it was, regardless of whether that day were monday or tuesday. now, in the actual problem, beauty is not told which day it is. however, by the law of total probability just as before, it follows that since she would have assigned probability / upon being told either that is monday or that it is tuesday, she should still assign probability / even if she does not know which day it is. thus, the answer for this variant of the problem again seems unambiguously and mathematically to be / . now, it seems clear that this variant is probabilistically equivalent to the original sleeping beauty problem, since in the original problem it is not relevant whether the one interview (if the nickel shows heads) takes place on monday or tuesday. so, this provides another (similar) argument for why the answer to the original problem is / . . . yet another variant: sleeping twins. consider the following variant of the sleeping beauty problem. suppose there are two twins, named beauty and beauty . we put them both to sleep (in separate, soundproof rooms), and flip a fair nickel. if the nickel shows tails, we wake and interview each of them (separately). if the nickel shows heads, we flip a dime. if the dime shows tails we interview beauty only, while if the dime shows heads we interview beauty only. what probability should each of them assign, upon being interviewed, to the event that the nickel showed heads? it is clear that in this variant, the situation for beauty is precisely the same as that of the peon in the above subproblem. hence, as in that subproblem, beauty should assign probability / to the nickel showing heads. similarly, beauty should also assign probability / to the nickel showing heads. on the other hand, if we regard beauty and beauty as a “unit”, then together they behave (probabilistically speaking) just like sleeping beauty in the original problem. indeed, the total number of times that beauty and beauty will be interviewed is two if the nickel is tails, and one if the nickel is heads. so, since each of beauty and beauty should assign the probability / , this suggests that sleeping beauty in the original problem should also assign probability / . indeed, this argument is very similar to, and perhaps more intuitive than, the argument given in section above. however, it is not completely definitive, due to the possible confusion over conditioning on the same person being interviewed twice (in the original problem), versus two different people each being interviewed once (in this variant). . . a simple argument why / must be wrong. another mathematical insight into the original sleeping beauty problem can be gained by conditioning on the day of the interview, i.e. by considering how the probabilities would change if beauty knew which day it was. recall that, in the original problem, beauty is interviewed on both monday and tuesday if the nickel showed tails, but is interviewed on monday alone if the nickel showed heads. suppose first that beauty is informed that her interview is taking place on monday. then, since precisely one interview would be conducted on monday regardless of whether the nickel showed heads or tails, she should at that point assign equal probabilities to the nickel showing heads or tails. in other words, we must have p (nickelheads |monday) = / , where monday is the event that “the interview is taking place on monday”. on the other hand, suppose beauty is informed that her interview is taking place on tuesday. then, since it is impossible to have an interview on tuesday if the nickel shows heads, she should at that point assign probability zero to the nickel showing heads. that is, we must have p (nickelheads |tuesday) = . it then follows, again by the law of total probability, that p (nickelheads) = p (monday) p (nickelheads |monday)+p (tuesday) p (nickelheads |tuesday) = p (monday) ( / ) + p (tuesday) ( ) = p (monday) / . now, it is not clear what value beauty should assign to p (monday), the probability (without any additional knowledge) that her interview is in fact taking place on monday. is it / , since she could be interviewed on either day? or / , since two of the three possible interview situations (heads-monday, tails-monday, tails-tuesday) involve monday? or / , reasoning that the probabilities of those three possible interview situations are respectively / , / , and / , and / + / = / ? in any case, since sometimes interviews will take place on tuesday, we must have p (tuesday) > , whence p (monday) = − p (tuesday) < , whence p (nickelheads) = p (monday) / < / . hence, this argument allows us to see directly that the answer / cannot be correct. (of course, once we agree that p (nickelheads) = / is the correct answer to the original problem, then working backwards we can conclude that p (monday) = / .) . . generalisation to other numbers and probabilities. once we accept the above reasoning, then it can also be applied to various generalisations of the original problem. for example, if beauty will instead be interviewed n times (with amnesia each time) if the nickel showed tails, but just once if the nickel showed heads, then it follows (by replacing the dime by an n-sided die) that the answer becomes /(n + ). the original problem corresponds to n = . or, if the nickel actually was not a fair coin but instead had a priori probability q of coming up heads (and −q of coming up tails), then the answer would become (q/ )/(q/ + ( − q)) = q/( − q). the original problem corresponds to q = / . if we combine both of the above modifications simultaneously, then the answer would become q/(n−(n− )q). the original problem corresponds to the values n = and q = / . many other similar variations can be solved in a similar fashion. . relation to other probability puzzles. the sleeping beauty problem is reminiscent of certain other well-known probability puz- zles in which a conditional probability at first appears to be / , but upon reflection is actually / . we review two such puzzles here, and then consider their relation to the sleeping beauty problem. . . bertrand’s box. the bertrand’s box probability puzzle was proposed by joseph bertrand in . it is sometimes called (in an equivalent “drawers” version) the three desk problem or three drawers problem, or (in an equivalent “cards” version, see e.g. rosenthal ) the three- card thriller or three-card swindle. it can be stated as follows: there are three boxes. box # contains two gold coins, box # contains two silver coins, and box # contains one gold and one silver coin. one box is chosen uniformly at random, and one coin is chosen uniformly at random from that box. suppose the chosen coin is gold. what is the probability that the chosen box was box # ? in this problem, many people will reason (correctly) that observing the gold coin imme- diately eliminates box # . they will then reason that boxes # and # must (still) be equally likely, so the probability of box # must be / . however, what the question is really asking is for the conditional probability p (box |coingold). this can easily be computed (e.g. rosenthal, ) as: p (box |coingold) = p (box , coingold) p (coingold) = p (box ) p (coingold |box ) p (coingold) = ( / )( / ) / = / , . hence, the answer is / . (if that seems counter-intuitive, note that conditional on coingold, the chosen coin was equally likely to be any of the three gold coins available, only one of which is in box # .) . . monty hall problem. another probability puzzle is the monty hall problem (vos savant, ), which may be stated as follows: a car is equally likely to be behind any one of three doors. you select one of the three doors (say, door # ). the host then reveals one non-selected door (say, door # ) which does not contain the car. at this point, you choose whether to stick with your original choice (i.e. door # ), or switch to the remaining door (i.e. door # ). what is the probability that you will win the car if you stick with your original choice? most people, upon first hearing this problem, believe (vociferously!) that the car is equally likely to be behind either of the two unopened doors, so the probability of winning is / regardless of whether you stick or switch. however, in fact the probabilities of winning are / if you stick, and / if you switch. from a conditional probability point of view, this error arises because most people intu- itively compute the wrong quantity. specifically, most people compute p (car |carnot ), i.e. the conditional probability that the car is behind door # given that it is not behind door # . this probability is easily computed (and intuitively seen) to be / . and, this would indeed be the correct answer if we assumed that the host just happened to reveal door # , by accident, and it just happened not to contain a car. (in rosenthal , this variant is called the monty fall problem.) however, in the original monty hall problem, what we actually want to compute is p (car |host ), i.e. the probability that the car is behind door # given that the host elected to open door # . this is related to the host’s motivations, so to compute this properly requires certain assumptions (which are implicit, though not explicit, in the original problem). namely, we assume that the host knows where the car is, and will always elect to open some door which is not the door you originally selected and which does not contain a car. furthermore, we assume the host will choose randomly (with probability / each) if there are two different such doors available. with these assumptions, we can compute (e.g. rosenthal, , ): p (car |host ) = p (car , host ) p (host ) = p (car ) p (host |car ) p (host ) = ( / )( / ) / = / , . hence, the answer is / . (if that seems counter-intuitive, note that the strategy of sticking will only succeed if your original guess happened to be correct, which had probability / . and since we knew the host was going to open some door not containing the car, observing this doesn’t change the probability / that we were right in the first place.) . . comparison to sleeping beauty. each of these two puzzles, like the sleeping beauty problem, involves computing a condi- tional probability which may at first seem to equal / , but is in fact equal to / . however, there are some subtle differences between the three scenarios. in bertram’s box, the erroneous answer / arises purely from a misunderstanding of conditional probability. once the rules of conditional probability are carefully brought to bear on the problem, the answer is clear and unambiguous. in the monty hall problem, there is some confusion about which conditional probability should actually be computed, and also about the implicit assumptions concerning the host’s behaviour. however, once these points are clarified, then again the rules of conditional probability can be carefully brought to bear on the problem, again providing a clear and unambiguous answer. by contrast, with the sleeping beauty problem, even upon careful reflection, it remains unclear how to mathematically formulate the notion of “conditional on currently being in- terviewed”. so, without some sort of reformulation, it seems that conditional probability cannot be brought to bear directly on sleeping beauty. however, the contribution of this paper is to present a slight reformulation of the sleeping beauty problem (by introducing a dime, while arguing that the dime does not affect the final answer), and to show that this slight reformulation can then be analysed unambiguously by the mathematics of conditional probability. in summary, bertram’s box and the monty hall problem, when formulated clearly, pro- vide unambiguous exercises in probability theory. by contrast, the sleeping beauty problem necessarily involves some sort of reformulation or philosophical analysis, though this paper attempts to keep such matters to an absolutely minimum. . final discussion. as mentioned in the introduction, lots of articles have previously been published about the sleeping beauty problem, including many which argue (as i do) that the answer is / . thus, i see the main contribution of this paper not as presenting a new result, but rather as providing a simple, mathematically-based justification for why / is correct. specifically, my main argument requires only (i) the mathematics of conditional proba- bility, e.g. p (a |b) = p (a and b) p (b) , and (ii) the “axiom” that people with identical relevant information will assign probabilities identically. my argument is then quite brief (sections and above), and can be summarised as: • by (i), the peon will assign probability / to the nickel being heads. • hence, by (ii), after beauty is informed that the dime shows heads (or, similarly, tails), she will assign probability / to the nickel being heads. • hence, by (i), beauty will assign probability / to the nickel being heads even before she is informed what the dime shows. • hence, by (ii), beauty will assign probability / to the nickel being heads even if the dime does not exist. so, it seems that any readers who accepts mathematical probability theory together with the above rather obvious “axiom”, should be convinced that / is the correct answer. of course, some such readers may have already been convinced by various previously published arguments, and might find the current paper superfluous. indeed, some of the previous arguments already contained some elements of conditional probability somewhat related to those herein (e.g. the “technicolor beauty” variant described in section . of the long paper by titelbaum, , has some points of commonality). and, conversely, some readers may continue to believe that / is the correct answer, for various philosophical reasons, even after reading my argument. so, i do not expect the current paper to completely resolve the controversy. despite these caveats, i hope and believe that there is merit in providing a simple, short, direct argument that / is the correct answer, using solid mathematical foundations with few assumptions and little philosophical ambiguity. acknowledgements: i am very grateful to gary malinas and calvin normore for discussing these issues with me, and to an anonymous referee for a very helpful report. references: arntzenius, f. (january ), reflections on sleeping beauty. analysis , – . bostrom, n. (july ), sleeping beauty and self-location: a hybrid model. synthese , – . dorr, c. (october ), sleeping beauty: in defence of elga. analysis , – . elga, a. (april ), self-locating belief and the sleeping beauty problem. analysis , – . horgan, t. (january ), sleeping beauty awakened: new odds at the dawn of the new day. analysis , - . lewis, d. (july ), sleeping beauty: reply to elga. analysis , – . monton, b. (january ), sleeping beauty and the forgetful bayesian. analysis , – . neal, r. m. ( ), puzzles of anthropic reasoning resolved using full non-indexical con- ditioning. technical report no. , dept. of statistics, university of toronto. piccione, m. and rubinstein, a. (july ), on the interpretation of decision problems with imperfect recall. games and economic behavior ( ), – . pust, j. (january ), horgan on sleeping beauty. synthese , - rosenthal, j.s. ( ), struck by lightning: the curious world of probabilities. joseph henry press, washington, d.c. rosenthal, j.s. (september ), monty hall, monty fall, monty crawl. math horizons, – . titelbaum, m.g. ( ), the relevance of self-locating belief. philosophical review ( ), – . vos savant, m. (sept. , ), ask marilyn column. parade magazine, p. . weintraub, r. (january ), sleeping beauty: a simple solution. analysis , - . wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ do younger sleeping beauties prefer a technological prince? | scholarly publications skip to main content leiden university scholarly publications home submit about select collection all collections this collection academic speeches dissertations faculty of archaeology faculty of governance and global affairs faculty of humanities faculty of science faculty of social and behavioural sciences leiden journals, conference proceedings and books leiden law school leiden university press medicine / leiden university medical centre (lumc) research output ul search box persistent url of this record https://hdl.handle.net/ / documents download avr- -scientomsbtecprince not applicable (or unknown) open access full text at publishers site in collections this item can be found in the following collections: centre for science and technology studies (cwts) raan, a.f.j. van; winnink, j.j. ( ) do younger sleeping beauties prefer a technological prince? article / letter to editor in this paper we investigate recent sleeping beauties cited in patents (sb-snprs). we find that the increasing trend of the relative number of sbs stopped around . moreover, we find that the time lag between the publication year of the sb-snprs and their first citation in a patent is becoming shorter in recent years. our observations also suggest that, on average, in the more recent years sbs are awakened increasingly earlier by a ‘technological prince’ rather than by a ‘scientific prince’. these observations suggest that sbs with technological importance are ‘discovered’ earlier in an application-oriented context. then, because of this earlier recognized technological relevance, papers may be cited also earlier in a scientific context. thus early recognized technological relevance may ‘prevent’ papers to become an sb. the scientific impact of sleeping beauties is generally not necessarily related to the technological importance of the sbs, as far as measured with... show more in this paper we investigate recent sleeping beauties cited in patents (sb-snprs). we find that the increasing trend of the relative number of sbs stopped around . moreover, we find that the time lag between the publication year of the sb-snprs and their first citation in a patent is becoming shorter in recent years. our observations also suggest that, on average, in the more recent years sbs are awakened increasingly earlier by a ‘technological prince’ rather than by a ‘scientific prince’. these observations suggest that sbs with technological importance are ‘discovered’ earlier in an application-oriented context. then, because of this earlier recognized technological relevance, papers may be cited also earlier in a scientific context. thus early recognized technological relevance may ‘prevent’ papers to become an sb. the scientific impact of sleeping beauties is generally not necessarily related to the technological importance of the sbs, as far as measured with number and impact of the citing patents. the analysis of the occurrence of inventor-author relations as well as the citation years of inventor-author patents suggest that the scientific awakening of sleeping beauties only rarely occurs by inventor-author self-citation. show less quantitative studies of science all authors raan, a.f.j. van; winnink, j.j. date - - journal scientometrics volume issue pages - doi doi: . /s - - - link https://doi.org/ . /s - - - © - leiden university a service provided by leiden university libraries contact about us recently added digital collections student repository c:/dokumente und einstellungen/volker/desktop/beautythesis/thesis.dvi measurement of beauty production in deep inelastic scattering at hera volker michels measurement of beauty production in deep inelastic scattering at hera dissertation zur erlangung des doktorgrades des departments physik der universität hamburg vorgelegt von volker michels aus lüneburg korrigierte fassung ( . . ) gutachter der dissertation: dr. b. list prof. dr. r. klanner gutachter der disputation: prof. dr. p. schleper dr. h. jung datum der disputation: . . vorsitzender des prüfungsausschusses: dr. m. martins vorsitzender des promotionsausschusses: prof. dr. j. bartels dekan der fakultät mathematik, informatik, naturwissenschaften: prof. dr. a. frühwald abstract a measurement of the beauty production cross section in ep collisions at a centre-of-mass energy of gev is presented. the data was collected with the h detector at the hera collider in the years - and corresponds to an integrated luminosity of pb− . events are selected by requiring the presence of at least one jet together with a muon in the final state. the large mass of b-flavoured hadrons is exploited to identify events containing beauty quarks on a statistical basis. single and double differential cross sections are measured in deep inelastic scattering, with photon virtualities . < q < gev . the results are compared to perturbative qcd calculations. the next-to-leading order prediction is . σ below the measurement. the deficiencies of the pre- diction are found in the forward direction of the muon, which is defined by the direction of the proton beam, and at low transverse momenta of the muon and jet. the leading-order predictions, which are augmented by parton showers, describe the shape of the measurements very well, but not the normalization. the predictions are about a factor two too low, which is compatible with the next-to-leading order prediction. kurzfassung eine messung des wirkungsquerschnittes für beauty-quark produktion in ep-kollisionen bei einer schwerpunktsenergie von gev wird vorgestellt. die daten wurden mit dem h -detektor am hera-beschleuniger in den jahren - aufgezeichnet und entsprechen einer integrierten luminosität von pb− . für die auswahl der ereignisse wird mindestens ein jet zusammen mit einem myon verlangt. die große masse von hadronen mit beauty-quarks wird ausgenutzt, um ereignisse mit beauty-quarks auf einer statistischen weise zu identifizieren. einfach- und doppelt-differentielle wirkungsquerschnitte wer- den in tief-inelastischer streuung gemessen, mit photonvirtualitäten , < q < gev . die ergebnisse werden mit perturbativen qcd berechnungen ver- glichen. die vorhersage in nächst führender ordnung ist , σ niedriger als die messung. die niedrigeren werte der vorhersage werden in vorwärtsrichtung für das myon, welche gegeben ist durch die richtung des protonstrahls, und bei niedrigen transversalimpulsen für das myon und den jet gemessen. die vorher- sagen in führender ordnung, ergänzt durch partonenschauer, beschreiben die form der messungen sehr gut, nicht jedoch die normierung. die vorhersagen sind ungefähr einen faktor zwei zu niedrig, was kompatibel ist mit der vorher- sage in nächst führender ordnung. contents contents heavy flavour production at hera . kinematics of high-energy ep scattering . . . . . . . . . . . . . . . . quark parton model and proton structure functions . . . . . . . . . quantum chromo dynamics (qcd) . . . . . . . . . . . . . . . . . . . qcd improved parton model . . . . . . . . . . . . . . . . . . . . . . . . parton evolution models . . . . . . . . . . . . . . . . . . . . . heavy quark production . . . . . . . . . . . . . . . . . . . . . . . . . parton hadronization . . . . . . . . . . . . . . . . . . . . . . . . . . . charm and beauty hadrons . . . . . . . . . . . . . . . . . . . . . . . . monte carlo event generators . . . . . . . . . . . . . . . . . . . . . . nlo calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . the experiment . hera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . h detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . tracking system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . central silicon tracker (cst) . . . . . . . . . . . . . . . . . . . . central proportional chamber (cip) . . . . . . . . . . . . . . . central jet chamber (cjc) . . . . . . . . . . . . . . . . . . . . . outer z chamber . . . . . . . . . . . . . . . . . . . . . . . . . . forward tracker . . . . . . . . . . . . . . . . . . . . . . . . . . calorimetry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . liquid argon calorimeter (lar) . . . . . . . . . . . . . . . . . . spacal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . muon system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . luminosity measurement . . . . . . . . . . . . . . . . . . . . . . . . . trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . previous experimental results . experimental methods . . . . . . . . . . . . . . . . . . . . . . . . . . . measurements at hera . . . . . . . . . . . . . . . . . . . . . . . . . . . photoproduction . . . . . . . . . . . . . . . . . . . . . . . . . . . deep inelastic scattering . . . . . . . . . . . . . . . . . . . . . . fixed target . . . . . . . . . . . . . . . . . . . . . . . . . . . . measurements at other colliders . . . . . . . . . . . . . . . . . . . . . . pp̄ collisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . γγ collisions . . . . . . . . . . . . . . . . . . . . . . . . . . . event reconstruction . identification and reconstruction of the scattered lepton . . . . . . . identification and reconstruction of the muon . . . . . . . . . . . . . . track reconstruction in the inner drift chambers . . . . . . . . track reconstruction in the instrumented iron . . . . . . . . . reconstruction of the hadronic final state . . . . . . . . . . . . . . . . selection of input objects . . . . . . . . . . . . . . . . . . . . . . hadroo algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . treatment of calorimetric energy deposition for muons . . . . jet reconstruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . longitudinally invariant kt -clustering algorithm . . . . . . . . . jets in the breit frame . . . . . . . . . . . . . . . . . . . . . . kinematic variables . . . . . . . . . . . . . . . . . . . . . . . . . . . event selection . data sample . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . run selection and detector status . . . . . . . . . . . . . . . . . trigger selection . . . . . . . . . . . . . . . . . . . . . . . . . . monte carlo samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . background sources . . . . . . . . . . . . . . . . . . . . . . . . z vertex distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . selection of dis events . . . . . . . . . . . . . . . . . . . . . . . . . . selection of muons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . muon identification efficiency . . . . . . . . . . . . . . . . . . . selection of jets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . summary of the selection . . . . . . . . . . . . . . . . . . . . . . . . measurement . cross section definition . . . . . . . . . . . . . . . . . . . . . . . . . . cross section determination . . . . . . . . . . . . . . . . . . . . . . . measurement of beauty fractions . . . . . . . . . . . . . . . . . . . . . . relative transverse momentum . . . . . . . . . . . . . . . . . . . binned likelihood fit . . . . . . . . . . . . . . . . . . . . . . . . fit results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . efficiency and acceptance corrections . . . . . . . . . . . . . . . . . . qed corrections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . systematic uncertainties and cross checks . . . . . . . . . . . . . . . . systematic uncertainties . . . . . . . . . . . . . . . . . . . . . . . cross checks . . . . . . . . . . . . . . . . . . . . . . . . . . . results . theoretical models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . total visible cross section . . . . . . . . . . . . . . . . . . . . . . . . differential cross sections . . . . . . . . . . . . . . . . . . . . . . . . . . comparison to nlo prediction . . . . . . . . . . . . . . . . . . . comparison to monte carlo prediction . . . . . . . . . . . . . double differential cross sections . . . . . . . . . . . . . . . . . . . . . comparison to nlo predictions . . . . . . . . . . . . . . . . . . comparison to monte carlo predictions . . . . . . . . . . . . . analysis in the breit frame . . . . . . . . . . . . . . . . . . . . . . . summary and discussion of the results outlook a run selection b transformation to the breit frame c cross section tables d level z-vertex trigger d. overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. . fast track trigger . . . . . . . . . . . . . . . . . . . . . . . . d. . z vertex trigger . . . . . . . . . . . . . . . . . . . . . . . . . d. data flow and hardware . . . . . . . . . . . . . . . . . . . . . . . . d. . front end modules and multipurpose processing boards . . d. . key technologies . . . . . . . . . . . . . . . . . . . . . . . . . d. implementation of the z vertex trigger . . . . . . . . . . . . . . . . d. . vhdl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. . hit finding and z measurement . . . . . . . . . . . . . . . . . d. . segment finding . . . . . . . . . . . . . . . . . . . . . . . . . d. . merging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. . linking and trigger decision . . . . . . . . . . . . . . . . . . d. . trigger element generator unit . . . . . . . . . . . . . . . . d. . timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. . cosmic runs . . . . . . . . . . . . . . . . . . . . . . . . . . . d. . luminosity runs . . . . . . . . . . . . . . . . . . . . . . . . . list of figures list of tables references danksagung introduction quantum chromo dynamics (qcd) describes one of the fundamental forces of na- ture, the strong force. the study of the production of heavy quarks at the electron proton collider hera gives insight into various aspects of qcd, both at the short distances where perturbative calculations are possible (perturbative regime), and at larger distances where only phenomenological approaches exist (non-perturbative regime). the large masses of heavy quarks set an energy scale, where perturbative qcd is expected to give reliable predictions. this holds true in particular for the production of beauty quarks which have a mass of about gev. in this thesis open beauty production is studied in the region of deep inelastic scat- tering (dis) in the range . < q < gev , where q is the virtuality of the exchanged photon. a muon from a semi leptonic heavy quark decay and a jet are required in the final state. the momentum of the original quark, which is not visible in the final state directly, can be approximated by the energy and direction of the observed jet. the fraction of beauty events of the data sample is determined on a statistical basis, using the large momentum of the muon with respect to the jet axis (prelt ) for beauty quarks. in comparison to the photoproduction regime (q ≈ gev ), the cross section and therefore the statistics of the data sample is small in the dis regime. on the other hand the structure of the photon is not important for the dis regime, which helps to reduce the uncertainties of theoretical predictions. q provides an additional hard scale apart from the jet transverse momentum and the quark mass. this allows a study of the multiscale problem: the qcd predictions may become unreliable if several hard scales are present due to large coefficients in the perturbation series. in this thesis differential cross sections as a function of different observables are compared to theory predictions. these are available in the form of next-to-leading order calculations of the hard matrix element with respect to αs, the coupling con- stant of the strong interaction. full event generators perform the calculation in leading order, and the long distance, non perturbative regime is modelled using phenomenological approaches. for a further investigation of the interesting regions of phase space where deviations to the predicitons are observed double-differential cross sections are determined. in the region of phase space investigated in this analysis, both the transverse mo- mentum of the jet and √ q are comparable to the beauty quark mass. therefore the calculations in the massive scheme are expected to give reliable results. in this scheme the beauty and charm quark are not treated as active flavours inside the proton, but are produced in the hard interaction process (boson-gluon fusion). this process is sensitive to the gluon density of the proton which can be determined from the scaling violations of the inclusive cross sections. using information gained on the gluon density, predictions of heavy quark production become possible. in this thesis direct measurements of heavy quark production are made thus providing a test of such predictions. this thesis is organized as follows: chapter gives a theoretical introduction to heavy quark production at hera. in chapter the h detector and the relevant subdetectors are introduced. in chapter an overview of experimental methods and previous measurements at hera and elsewhere is given. the explanation if the experimental work of this thesis starts with chapter , where the event reconstruction is discussed in detail. in chapter the selection of the event samples, in both data and monte carlo, is presented, followed by a discussion of the beauty quark measurement in chapter . here the prelt method, which is used to obtain the beauty fraction of the data sample together with all correction factors applied to the data to obtain the cross sections as well as systematic studies are discussed in detail. in chapter the results are presented: the total visible cross section for beauty quark production, differential and double differential cross sections as a function of different observables compared to next-to-leading order calculations and two differ- ent monte carlo predictions. in chapter the summary of the results is given. some results are compared to other measurements and discussed in a more general context. the presentation of the analysis is concluded with chapter where an outlook is given and some potential improvements of the measurement are discussed. in appendix d a topic not related to the analysis but part of the work done for this thesis is discussed. a z vertex trigger based on drift chamber signals was implemented as a part of the fast track trigger (ftt) upgrade project of the h experiment. the principle and implementation of this trigger and the results thereof are discussed. chapter heavy flavour production at hera . kinematics of high-energy ep scattering the scattering process ep → lx ( . ) is described by the exchange of a virtual gauge boson as illustrated in figure . . for this thesis only the neutral current process ep → ex is relevant where a virtual photon or z boson is exchanged. the exchange of virtual w bosons leads to the charged current process ep → νex with a neutrino in the final state. the photon virtuality q is given by the squared momentum transfer q = −q = −(k − k′) , ( . ) the squared centre-of-mass energy of the reaction is s = (p + k) . ( . ) the relative energy transfer at the electron-boson vertex in the proton rest frame is given by y = p · q p · k , ≤ y ≤ , ( . ) the bjorken scaling variable as x = q p · q , ≤ x ≤ . ( . ) the bjorken scaling variable can be interpreted as the fraction of the proton’s mo- mentum carried by the interacting quark in the infinite momentum frame. neglect- ing the lepton and proton masses, these variables are related by the equation q = x · y · s. ( . ) the phase space region of small momentum transfers (q ≈ ) is called photopro- duction, at h usually selected by the condition q < gev . the region of larger q is referred to as deep inelastic scattering (dis). � �� figure . : deep inelastic electron-proton scattering at hera in the single boson exchange picture. for the neutral current process a photon or z boson is exchanged, resulting in an final state electron. in the case of a charged current process a w boson is exchanged, resulting in an outgoing antineutrino. the four momenta are denoted in parantheses. . quark parton model and proton structure func- tions in the quark parton model (qpm) picture [ , ] the proton is made of quasi- free, non interacting particles, called partons, which can be identified as quarks. the double differential cross-section for electron proton scattering can then be de- scribed by the incoherent sum of electron parton scatterings d σ dxdq = πα xq ( + ( − y) ) ∑ i e i xqi(x). ( . ) the distribution function qi(x) gives the probability that the struck quark i carries the momentum fraction x of the proton. the momentum distribution xq(x) is called parton distribution function (pdf). the inelastic electron proton scattering cross-section is given by the general formula dσ ∼ leμν w μν , ( . ) where leμν is the tensor describing the leptonic current and w μν is the tensor de- scribing the hadronic current. for unpolarized neutral current scattering, neglecting parity violating effects due to the weak interaction, the hadronic tensor has the form w μν = w (−gμν ) + gμgν q + w m ( pμ − p · q q qμ ) ( pν − p · q q qν ) , ( . ) where w and w are structure functions and m is the proton mass. when ignoring mass terms and redefining the structure functions as f = w and f = (p · q)w /m , the double differential cross-section can be expressed as d σ dx dq = πα s xq ( xy f (x, q ) + ( − y)f (x, q ) ) . ( . ) in terms of f and the longitudinal structure function fl = f − xf the cross- section may also be written as d σ dx dq = πα s xq ( y+f (x, q ) − y fl(x, q ) ) , ( . ) where y+ = + ( − y) . the longitudinal structure function fl is related to the exchange of a longitudinally polarised photon. this contribution is kinematically suppressed due to the factor y and leads to sizeable effects only for large inelastic- ities. when compared to equation ( . ), the quark parton model predicts that the struc- ture function depends only on x and not on q : f (x, q ) = f (x) = ∑ i e i xqi(x). ( . ) this effect, known as scaling, can be seen for x ∼ . for hera and fixed target data, as shown in figure . . scaling violations become visible at low x, where f rises with increasing q . this can be interpreted by qcd (see section . ) due to the parton dynamics and the corresponding rise of the gluon density towards small x. . quantum chromo dynamics (qcd) quantum chromo dynamics is a non-abelian gauge theory that describes the in- teractions between quarks and gluons. quarks are spin- / color charged particles building the hadronic matter. massless spin- gluons are the mediators of the strong force between quarks. the interaction is based on a su ( )c color symmetry group and three-fold color charges. the symmetry group allows for a rich interaction structure. the exchange quanta itself carry charge, which is the main difference to quantum electrodynamics (qed). loop graphs (see figure . ), contributing to higher orders of the expansion of scattering amplitudes in αs, are divergent. qcd is a renormalizable field theory: to ensure finite results in all orders of the expansion in αs, a renormalized (redefined) coupling αs(μr) is defined, that depends on the renormalization scale μr. the leading order equation for the running coupling is αs(μr) = ( b ln( μ r Λ qcd ) )− , with b = − nf π , ( . ) where nf is the number of active flavours. the scale parameter Λqcd depends on the renormalization scheme and on the number of active flavours. it was determined experimentally for the m s scheme (see section . ) to be about mev [ ]. the running coupling is shown in figure . . for μr much larger than Λqcd, the effective coupling is small and a perturbative description is applicable. this region of asymptotic freedom corresponds to the quark parton model picture of quasi-free quarks. for μr of the order of Λqcd the strong binding force becomes important, which confines the quarks within hadrons (confinement). hera f f em -l og (x ) q (gev ) zeus nlo qcd fit h pdf fit h - h (prel.) / zeus / bcdms e nmc x= . e- x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . x= . figure . : proton structure function f for various fixed values of x, measured by h , zeus and different fixed target experiments together with dglap-based fits. for better visibility an offset (− log x) is applied to each data point. figure . : virtual corrections to the gluon propagator: gluon loop (left) and fermion loop (right). . . . . qcd αs(mz) = . ± . hera et jet (gev) α s figure . : running of the effective coupling constant αs as a function of the transverse jet energy. shown is the combined h and zeus measurement and the qcd prediction [ ]. figure . : diagrams contributing to o(αs) correction to the quark parton model by emission of gluons from the quark line (γ∗q → gg). for qcd compton processes the gluon can either be emitted from the initial or final state quark. figure . : o(αs) boson gluon fusion process γ∗g → qq (bgf). . qcd improved parton model in qcd the scaling of the structure functions is broken due to o(αs) corrections to the parton model result. diagrams contributing to this corrections by emission of gluons from the quark line (γ∗q → qg) are shown in figure . . therefore in qcd the structure function is q dependent and given by [ ] f (x, q ) = x ∑ q,q̄ e q [ q (x) + αs π ∫ x dξ ξ q (ξ) { pqq ( x ξ ) ln q κ + c ( x ξ )} + ... ] , ( . ) where c(x) is a calculable function and the splitting function pqq is given in leading order by the equation pqq(x) = ( + x ( − x)+ + δ( − x) ) . ( . ) this splitting function is always used inside an integral and is therefore a distribution. the plus description is used, the integral with any sufficiently smooth function f is ∫ dx f (x) ( −x)+ =∫ dx f (x)−f ( ) −x and ( −x)+ = −x for ≤ x ≤ . the singularity for x → is due to emissions of soft gluons. the scaling is broken by logarithms of q /κ , where κ is a cut-off that has to be introduced due to collinear divergencies, which arise when the gluon is emitted parallel to the quark. this problem is solved by absorbing these singularities into the quark distribution, which now becomes scale dependent: q(x, μ f ) =q (x) + αs π ∫ x dξ ξ q (ξ) ( pqq( x ξ ) ln μ f κ − cq( x ξ ) ) + αs π ∫ x dξ ξ g (ξ) ( pqg( x ξ ) ln μ f κ + cg( x ξ ) ) + ... ( . ) in this formula, o(αs) contributions from the process γ∗g → qq (see figure . ) are included and folded with the bare gluon distribution g (x), where the corre- sponding splitting function is pqg(x) = ( x + ( − x) + ( − x) ) . ( . ) the factorization scale μf defines the scale where the singularities are contributed to the quark density which cannot be calculated perturbatively. the wilson coeffi- cient functions cq and cg depend on the factorization and renormalization schemes, as the amount of finite contributions to the quark density is arbitrary. for the dis factorization scheme the structure function f has the simple form f (x, q ) = x ∑ q,q̄ e q q(x, q ). ( . ) for the m s factorization scheme, where not all the gluon contribution is absorbed into the quark distribution, the structure function has the form f (x, q ) =x ∑ q,q̄ e q ∫ x dξ ξ q(ξ, q ) ( δ( − x ξ ) + αs π cm sq ( x ξ ) + ... ) + x ∑ q,q̄ e q ∫ x dξ ξ g(ξ, q ) ( αs π cm sg ( x ξ ) + ... ) . ( . ) the coefficient functions are cm sq (z) = δ( − z) + αs π c q + ... ( . ) cm sg (z) = αs π c g (z) + ... , ( . ) with c q (z) = ( ln( − z) − ( − z)+ − ( + z) ln( − z) − + z − z ln z + + z − ( π + )δ( − z) ) , ( . ) figure . : gluon and valence quark densities of the proton as obtained from h and zeus fits. c g (z) = ( (z + ( − z) ) ln( − z z ) + z( − z) − ) . ( . ) equations ( . ) and ( . ) are based on the factorization theorem [ ] which states that the cross-section for dis may be written as the convolution of a hard scattering cross-section and a non-perturbative parton density. from fits to the measured f structure functions the parton density functions can be determined. the gluon and valence quark distributions as determined from h and zeus fits are shown in figure . . the gluon density becomes important and exceeds the quark densities by far for the small x region. this is the reason for the observed scaling violations of the structure functions at low x. to compare the data measured in this analysis with theory predictions, sets of parton density functions are used that are based on global fits, provided by the cteq [ ] group. . . parton evolution models the scale dependent parton densities discussed in the previous section include soft processes up to the factorization scale μf . they are not calculable by perturbative qcd, nevertheless qcd predicts the scale dependence. if the densities are measured at a scale μ , an evolution to a scale μ > μ is possible. the variations of q(x, μ ) and g(x, μ ) with respect to ln μ are given by the dglap equations [ , , , , ] ∂qi(x, μ ) ∂ ln μ = αs π ∫ x dξ ξ ( qi(ξ, μ )pqq(x/ξ) + g(ξ, μ )pqg(x/ξ) ) ( . ) dokshitzer, gribov, lipatov, altarelli, parisi figure . : illustration of the four different splitting functions used for the dglap equations. z denotes the longitudinal momentum fraction. and ∂g(x, μ ) ∂ ln μ = αs π ∫ x dξ ξ (∑ i qi(ξ, μ )pgq(x/ξ) + g(ξ, μ )pgg(x/ξ) ) . ( . ) these equations depend on the splitting functions pqq, pgq, pqg and pgg, which are illustrated in figure . . they give the probability for a parton j to emit a parton i with momentum pi = zpj. the dglap approach is based on resumming the leading αs ln(q /μ ) terms. this leading log approximation (lla) requires a strong ordering in the transverse momenta of the emitted partons (see figure . ): μ < p t, < p t, < ... < p t,n < q . ( . ) this approach describes successfully the scaling violations of the structure functions observed at hera down to the smallest accessible x. the dglap evolution is used to model parton showers for monte carlo programs (see section . ). the probability for evolving from a virtual mass scale t to t without resolvable branching is given by the ratio Δ(t )/Δ(t ), where Δ(t) is the sudakov form factor (for a deeper discussion see e.g. [ ]). the ccfm approach [ , , , ] is an alternative to the dglap approach. it is based on the angular ordering constraint, which is a property of qcd: in a cascade of gluon and quark emissions the angles of the emitted particles decrease when proceeding down one branch. an unintegrated kt dependent gluon density this resumming is achieved by replacing αs by the running coupling. ciafaloni, catani, fiorani, marchesini figure . : subsequently emitted gluons build a gluon ladder. for the dglap approach the emitted gluons are ordered in transverse momenta kt. a(xg, k t , μ f ) is used, allowing the partons entering the hard matrix element to be off-shell. the ccfm approach, also called kt factorization, is equivalent to the dglap approach, also called collinear factorization, for large q and moderate x. this scheme avoids the problem of αs ln( /x) terms of the dglap solution which becomes important for small x and might spoil the convergence of the perturbation series. . heavy quark production the production of charm and beauty quark pairs at hera is an ideal testing ground for qcd as the masses of these heavy quarks set a hard scale which allows the mea- surements to be compared to perturbative calculations. at scales of the charm mass mc ≈ . gev and beauty mass mb ≈ . gev the strong coupling constant αs gets so small that processes with further gluons involved are expected to be sufficiently suppressed. in the model described so far, only light quarks are considered. several approaches exist to introduce beauty and charm quarks, they treat these quarks either as massless or massive: massive scheme as no charm or beauty density for the proton is assumed, this scheme is also called fixed flavour number scheme (ffns). heavy quarks are only produced per- turbatively in the hard interaction. the leading order (o(αs)) boson-gluon-fusion process and some next to leading order (o(α s)) processes are shown in figure . . the corresponding beauty structure function (the formalism is similar for charm quarks) is given by f b (x, q ) = ∫ x dz z xg (x/z, μ )cf fg (z, m b /q , μ ), ( . ) figure . : leading order (outer left) and next-to-leading order diagrams for heavy quark production in the massive scheme. where g is the gluon density for three light flavours, μ is the used scale (e.g. μ = m b + p tbb̄ ), and the massive fixed flavour coefficient function is given by cf fg (z, m b /q , μ ) = αs(μ ) π e b c ,f f g (z, m b /q ) + ... ( . ) for q � m b the gluon coefficient function is given by c ,f fg (z, m b /q ) = c g + ( z + ( − z) ) ln( q m b ), ( . ) where c g is the gluon coefficient function from the massless dglap formalism (equation ( . )) and an additional term proportional to ln( q m b ) appears, represent- ing collinear gluon emissions from the heavy quarks. for q � m b , terms proportional to ( αs ln( q m b ) )n , which are considered up to the order o(α s), might spoil the convergence of the perturbation series. the same holds for terms proportional to ( αs ln( p t m b ) )n for p t � m b . if p t and q are not too large compared to m b , this method is reliably applicable. this scheme is used for the theory predictions for this analyis. massless scheme in this scheme heavy quarks are considered as massless active flavours of the pro- ton by introducing heavy quark structure functions for scales larger than the heavy quark mass. therefore this scheme is called zero-mass variable flavour num- ber scheme (zm-vfns). this results in a resummation of the terms representing collinear gluon radiations. the parton dynamics of heavy quarks can then be de- scribed by the dglap approach in a similar way as for the light quarks. the disadvantage is that the threshold behaviour for low q can not be described prop- erly by this scheme. some leading and next to leading order diagrams for this scheme are shown in figure . . the variable flavour number scheme (vfns) is a mixed scheme that interpo- lates between the vfns and the ffns approach with a correct threshold behaviour at low q and heavy quark densities for large q . figure . : leading order (outer left) and next-to-leading order diagrams for heavy quark production in the massless scheme. . parton hadronization as a consequence of the colour confinement (see section . ), all experimental re- sults are derived from the observation of hadrons. the hadronization, also called fragmentation process, has to be modelled to allow the comparison to theoretical predictions. this process can be calculated perturbatively above a scale of ≈ gev. the evolution of a heavy quark from the factorization scale μf to this scale via sub- sequent gluon emissions and splittings is described in monte carlo simulations by the parton shower approach. the scale dependence of this evolution is described by the dglap evolution (see section . ). for the long distance, non perturbative part of the hadronization process different phenomenological models exist. for this analysis the string fragmentation model [ ] is used. in this model strings are formed by qq̄ pairs and the colour field between them (see figure . , left). the stored potential energy is proportional to the separation distance of the quarks. when this energy is large enough, the string breaks up and a new qq̄ pair is produced out of the vacuum. gluons are incorporated into this mechanism by kinks in the strings. finally the string fragments are combined to hadrons. the transverse momentum distribution is assumed to be gaussian, the longitudinal momentum frac- tion z is given by the fragmentation function dhq(z). the lund fragmentation function [ ], defined as dhq(z) ∼ z ( − z)a exp(−bm t /z), ( . ) is used as default for the monte carlo simulation for this analysis. here mt is the transverse mass m + p x + p y of the hadron, and a and b are free parameters. for heavy quarks the lund-bowler [ ] fragmentation function is used, which is a modification of equation ( . ). another widely used fragmentation function is the peterson fragmentation function [ ], given by dhq(z) ∼ /z ( − /z − �q/( − z)) , ( . ) where �q is a free parameter which is different for charm and beauty quarks, resulting in a harder fragmentation for beauty quarks. this means that beauty hadrons get mesons q q d is ta n c e time c d s u d u s d∗+ Κ Κ− Εc ( -z)z’ec zec ( -z)( -z’)z’’ec vacuum fluctuation until cut-off energy figure . : illustration of the string fragmentation model (left) and the inde- pendent fragmentation (right). on average a larger longitudinal momentum fraction of the initial parton. in this analysis this function is used for the systematic study of the fragmentation of heavy hadrons. a further fragmentation function is the kartvelishvili fragmentation function [ ], defined as dhq(z) ∼ z α( − z). ( . ) the string fragmentation model is similar to the independent fragmentation [ ] which is not used anymore. in this model the partons hadronize individually (see figure . , right). for each transition the initial parton is combined with a quark from a vacuum fluctuation. the other quark pair continues the fragmentation process. this cascade is stopped when all the energy is used up. another model which is not used for this analysis but mentioned for completeness is the cluster fragmentation model [ ] where clusters form colour singlets which decay isotropically into hadron pairs. . charm and beauty hadrons the most important properties of charm and beauty hadrons that can be exploited as experimental signatures on a statistical basis for heavy quark production are their large mass and lifetime (see section . ). the main properties of heavy hadrons are listed in table . . the much smaller ckm (cabbibo-kobayashi-maskawa) matrix element |vcb| responsible for the decay b → cw − compared to the matrix element |vcs| responsible for the decay c → sw + is the reason for the longer lifetime of beauty hadrons, which is about . ps, compared to . - ps for charm hadrons [ ]: |vcb| = . ± . ( . ) |vcs| = . ± . ( . ) this results in a larger decay length for beauty hadrons, where the lifetime effect is partially compensated by the larger lorentz-boost of charm hadrons. due to the hadron quark content lifetime [ps] cτ [μm] mass [gev] d+ cd . ± . . ± . d cū . ± . . ± . d s + cs̄ . ± . . ± . Λ+c ucd . ± . . ± . b+ ub . ± . . ± . d db̄ . ± . . ± . b s sb̄ . ± . . ± . Λ b udb . ± . ± table . : lifetime, decay length and mass of some selected charm and beauty hadrons. � � � � � � � � � � � � � �� figure . : diagrams for semi-leptonic decays of beauty quarks: direct (left) and the cascade decay via a charm quark (right). large beauty quark mass the semi-leptonic decay of beauty hadrons can be described by the spectator model [ , ], where the beauty quark decay is not affected by the light quarks (see figure . ). one can distinguish two modes for the decay b → μ x: for the direct process the beauty quark decays into cw and the w subsequently into a muon and neutrino. the branching ratio for this direct decay is about . % [ ]. for the indirect decay the charm quark decays further into sw , where the w decays into a muon and neutrino. in rare cases two muons can be produced as two w bosons appear in this indirect decay chain. the branching ratio for this indirect decay is about % [ ]. other decay chains as b → j/Ψ → μμ or b → τ x → μx′ have much smaller branching ratios. . monte carlo event generators monte carlo generators provide an event-by-event prediction of the full hadronic final state. this is the input of detector simluations needed to study detector effects and to determine detector acceptances and efficiencies. event generators model the underlying physics using several steps, based on the factorization theorem (see sec- tion . ). in figure . the different parts of an event generator are shown. all generators available at present calculate the hard matrix element in leading order αs. higher order qcd effects are modelled by the simulation of parton showers before and after the hard interaction. these parton showers are based on parton evolution equations (see section . . ), where a backward evolution from the hard ps ps h a d ro n is a ti o n h a d ro n s me p e figure . : illustration of the perturbative and non perturbative processes imple- mented in monte calo generators: hard matrix element (me), parton showers (ps) and the hadronization. matrix element to the proton is used for performance reasons. as the multi gluon emissions result in observable objects, event generators are in this sense superior to nlo predictions. for the hadronization part of the generators phenomenological fragmentation models (see section . ) are implemented. in addition hadron decays are modelled, e.g. semi-leptonic decays of heavy hadrons. after running the jet algo- rithm this hadron level prediction can be compared to data. for the determination of detector corrections this hadron level information is fed into detector simulations, usually based on the geant package [ ], which provides particle tracking through the different subdetectors. decays of long lived particles are simulated at this step. this simulation step is not part of the monte carlo generators and not discussed further. finally the simulated data is subject to the same reconstruction as the data (see section ). for this analysis the default event generator is rapgap [ ], used for a full simu- lation and in a separate mode to produce beauty events via boson gluon fusion. in both cases the leading order calculation is performed in the massive scheme. the in- clusive mode includes a full simulation, including quark parton model and processes of the order αs, like boson gluon fusion and qcd compton. higher order qcd effects are modelled using the dglap approach for the initial and final state par- ton showers. hadronization and particle decays are implemented using the jetset part of the pythia code [ – ]. the hadronization is modelled using the lund string fragmentation, where for heavy quarks the peterson fragmentation function can be used. rapgap is interfaced to the heracles program [ ], which simu- lates qed radiative corrections. it generates the eγ∗e vertex, including real photon emission from the incoming and outgoing electron and virtual corrections. by in- corporating these corrections at this level large correction factors on reconstruction level for the dis kinematic variables x, q and y can be avoided. as an alternative, the monte carlo generator cascade [ , ] is used. this pro- gram generates the boson gluon fusion process γ∗g∗ → qq̄ for light and heavy quarks using an unintegrated gluon density which is obtained from the measured structure function f . this model has the advantage that the gluon entering the hard subpro- cess is allowed to carry a non zero transverse momentum. the backward evolution of the gluon density is based on the ccfm model, final state parton showers are modelled based on the dglap approach (see section . . ). the hadronization pro- cess is again modelled by the jetset routine. qed radiation is not implemented in cascade. details about the monte carlo parameters used for the simulated samples and for the samples used for the comparison to the data can be found in section . and . , respectively. . nlo calculation the monte carlo integration program hvqdis [ ] provides the total and differ- ential cross sections for a number of variables for heavy quark production in deep inelastic scattering. the matrix element is calculated in next-to-leading order using the massive approach (see section . ) in the m s scheme (see section . ). the program provides two or three partons for the final state. to allow a comparison to data, an extended version of this program is used. the hadronization of beauty hadrons into beauty flavoured hadrons is modelled by rescaling the three-momentum of the quark using the peterson fragmentation function. semileptonic decays into a final state with a muon are modelled using the muon decay spectrum taken from jetset [ – ]. parton level jets are reconstructed by applying the kt algorithm (section . . ) to the outgoing partons. a comparison to data at hadron level re- quires a correction to the hadron level using a monte carlo generator like rapgap. this is explained in section . the main theoretical uncertainties of the nlo calcu- lation arise from the uncertainty of the beauty quark mass and the renormalization and factorization scales (see section ). chapter the experiment . hera two accelerators, one for electrons or positrons and one for protons, are housed in a common ring tunnel of . km circumference. this hera collider, the preaccel- erators and the location of the four interaction regions are illustrated in figure . , left. the proton ring is equipped with dipole magnets, main quadrupole magnets, correction quadrupoles, correction dipoles, all superconducting. about ma of protons were injected at an energy of gev and accelerated up to gev. the magnetic field for the proton ring was . tesla for the nominal beam energy produced by a current of a for the dipoles. the electron ring consists of more than normal conducting dipole magnets. the injection energy was gev, the lumi energy . gev. the usual beam current was about ma. a maximal longitudinal polarisation of % was achieved for the lepton beam using three spin rotator pairs. the lepton beam and proton beam consisted of up to bunches, where each bunch contained about particles. the bunch length was about mm for the leptons and, much longer, up to − cm for the protons. the revolution frequency was . khz. whereas the hera b and hermes experiments were using only the proton and lepton beam, respectively, the beams were brought to collison at the collider ex- periments h and zeus. every ns an intersection happened, which defined the hera bunch crossing rate of . mhz. the luminosity is given by l = πe f nb ieip σxσy , ( . ) where f is the revolution frequency, nb is the number of bunches, ie and ip are the electron and proton currents, and σx · σy is the spot size at the interaction point, with typical values of μm · μm. typical parameters of the lepton and proton beams are summarized in table . . after a shutdown and upgrade program to increase the luminosity, which included the installation of focussing magnets within the h and zeus detectors, luminosity hall north h hall east hermes hall south zeus hera hall west hera-b e p volkspark stadion m m r= m trab rennb ahn day a c c u m u la te d b y h [ p b - ] figure . : hera accelerator, preaccelerators and the four experiments h , zeus, hermes and hera b and accumulated lumi for the h experiment for the years - . electron-proton positron-proton proton/electron beam energy gev/ . gev proton/electron beam currents ma/ ma ma/ ma luminosity [cm− s− ] . · . · specific luminosity [ma− cm− s− ] . · . · spot size σx × σy [μm ] × table . : parameters of hera ii [ , ] operation resumed in in the electron-proton mode. in july the operation switched to positron-proton mode. the accumulated luminosities for the different years are shown in figure . , right. after dedicated low energy runs with a reduced proton beam energy to measure the longitudinal structure function fl, the hera operation ended at the end of june . . h detector the h detector [ ], which is currently being dismantled after the shutdown of hera, was a complex detector consisting of several subdetectors which were ar- ranged in a shell structure around the interaction point at the center of the detector. it was optimized for new particle production, neutral current inclusive measurements detector component abbreviation tracking detectors forward silicon detector fst central silicon detector cst backward silicon detector bst central inner proportional chamber cip central outer z drift chamber coz inner central jet chamber cjc outer central jet chamber cjc backward proportional chamber bpc calorimeters electromagnetic spaghetti calorimeter spacal em. hadronic spaghetti calorimeter spacal hadr. liquid argon calorimeter (electromagnetic) lar em. liquid argon calorimeter (hadronic) lar hadr. muon detectors instrumented iron: central muon detector cmd forward muon detector fmd table . : list of the main detector components of h (legend to figure . ). and charged current interactions. therefore the detector covered the whole π solid angle with a higher instrumentation in the proton direction to account for the asym- metric beam energies. the main design decisions were the use of liquid argon as detector medium and lead/copper as absorber for the calorimeters and a coil outside the calorimeters. a drawing of the detector is shown in figure . , the inner part is shown in figure . . the proton beam direction defines the positive z-axis, the x − y plane is per- pendicular to this axis, with the x-axis pointing to the center of the ring and the y-axis downward. the nominal interaction point defines the origin of the coordinate system. the polar angle φ of a particle trajectory is defined in the x−y plane where φ = defines the x-axis, the azimutal angle θ is defined with respect to the z-axis. the most inner detectors are tracking detectors used for identifying decay vertices, triggering and reconstruction of tracks. they are surrounded by calorimeters using liquid argon as active material for the measurements of particle energies. a lead- scintillator-fibre detector was used to identify the scattered electron in the backward direction. the superconducting magnet, which was outside the calorimeters, gener- ated a magnetic field of . tesla which was needed for the momentum measurement of charged particles. the return yoke of the magnet was instrumented with limited streamer tubes used to detect muons that penetrate the calorimeters. in the forward direction the detector was instrumented with a forward muon detector, which is not used for this analysis. as part of the hera ii upgrade program many subdetectors and trigger systems were improved, this includes the fast track trigger (ftt), which is used to trigger detector component abbreviation tracking detectors central silicon tracker cst central inner proportional chamber cip inner central jet chamber cjc central outer z drift chamber coz central outer proportional chamber cop outer central jet chamber cjc cjc electronics forward tracking detector ftd superconducting quadrupole magnet go forward tracker cables inner wall of lar vacuum tank backward proportional chamber bpc electromagnetic spaghetti calorimeter spacal em. photomultipliers for spacal em. hadronic spaghetti calorimeter spacal hadr. photomultipliers for spacal hadr. superconducting quadrupole magnet gg table . : the main component of the central h tracker and backward calorime- ters (legend to figure . ). shown is the configuration without forward and backward silicon detectors (fst, bst). in figure . ’ ’ denotes the nominal inter- action point. events based on drift chamber information and a combination with other subdetec- tors. the ftt is discussed in more detail in section d. . tracking system a radial view of the central tracking system is shown in figure . . the sub-detector closest to the interaction region is the central silicon tracker (cst) used for precise measurements of charged particle tracks close to the event vertex. this detector is surrounded by the central inner proportional chamber (cip) used for triggering. the most important tracking detectors are the inner and outer central jet cham- bers, cjc and cjc , with the central outer z-chamber between them. they cover the angular range in ◦ < θ < ◦. in the forward direction the forward tracking detector ftd delivers track infor- mation in the angular range ◦ < θ < ◦. the cst is supplemented by silicon detectors in the forward and backward region, the fst and bst, which were only operational for a fraction of the hera ii period due to repair work. the backward proportional chamber bpc refines the measurement of the scattered electron of the backward calorimeter. e le c tr o n s p ro to n s figure . : technical drawing of the h detector after the luminosity upgrade. for the different subdetectors see table . . m figure . : the inner part of the h detector, consisting of the central tracking system, the forward tracking system and backward calorimeter. the legend to the subdetectors is given in table . . not shown in this drawing are the forward and backward silicon detectors. figure . : radial view of the central tracking system at h . shown are from the inside to outside: cst ( ), cip ( ), cjc ( ), coz ( ), cjc ( ). rf -strips µ m implant pitch µ m readout pitch aluminium wire bonds carbon fiber rail apc amplifier and pipeline chip ceramic hybrid mm mm . mm readout lines on nd metal layer z-strips µ m pitch vias metal- to metal- n-side:p-side: decoder chip cst half ladder kapton cable figure . : central silicon detector: elliptical arrangement of the two layers of strip sensors (left) and detailed view of the n and p side of the strip sensors (right). . . central silicon tracker (cst) the cst delivers precise vertex and track information by refining tracks recon- structed in cjc and cjc . several analyses use this data and exploit lifetime effects of heavy quarks (see section . ). for the analysis presented in this thesis this information is not used. this detector consists of double-sided strip sensors which are arranged in two layers around the beam pipe at a distance between and cm due to the elliptical beam pipe in this region for hera ii (see figure . . , left). the p side of the sensors has strips parallel to the z-axis and delivers information in the rφ plane, the n side measures the z coordinate. the p and n side of the ladders, made of six sensors each, are illustrated in figure . . , right. more detailed information on the cst and the two endcap parts (fst, bst) of the h silicon tracker can be found in [ ]. . . central proportional chamber (cip) the central inner proportional chamber (cip) installed for hera ii is a multi- wire proportional chamber with wires parallel to the beam. detector layers enclose the cst at radii between and cm. the chamber covers a range − . < z < + . cm and ◦ < θ < ◦. the readout pads are arranged in a projective geometry which results in the same pattern for tracks that origin from the same z position. the cip trigger searches for track patterns, builds a z-vertex histogram from the number of tracks pointing to the bins along the beamline, and evaluates the histogram. a fast trigger decision on level (see section . ) allows an early rejection of background events without introducing dead time for data taking. the trigger decision is based on the total number of entries in the histogram and the fraction of central to backward entries (cip significance). a similar condition is used for the ftt z-vertex trigger (see section d). the fast response time of the detector also allows for a determination of time of the interaction (event t ). details on the detector and the trigger can be found in [ ]. . . central jet chamber (cjc) the central jet chamber is a drift chamber made of two parts, the inner chamber cjc that encloses the cip at an inner radius of . cm and the outer chamber cjc with an outer radius of . cm. an angular range ◦ < θ < ◦ is covered, defined by the acceptance of the cjc . the inner (outer) chamber is divided in ( ) cells, which are tilted with respect to the radial direction. this ensures that high momentum tracks cross the cell boundaries and can be measured within cells. each cell of cjc (cjc ) contains ( ) sense wires. the actual positions of these wires are shifted by an amount of ± μm (staggering). the hit position is measured using the drift time of charges to these signal wires (determined in a qt-analysis of the pulse shape, see section d. . ), drift velocity and the exact wire position. an ambiguity appears as it is not known from which side the charges drift to the wire resulting in the reconstruction of mirror hits. this left-right ambiguity can be resolved due to the crossing of cell boundaries and the staggering of the sense wires. the single hit resolution in the rφ-plane is about μm, in the z plane only about mm are achieved. the cjc is the main detector component that provides the data (hit information) used for the reconstruction of tracks in the central detector region. the reconstruc- tion algorithm delivers helix parameters of bent tracks due to the magnetic field, which is a measurement of the transverse momentum of the corresponding particle. the principle is described in some more detail in section . in the context of the muon track reconstruction. a fraction of the signal wires deliver information for the fast track trigger (ftt), which is described in some more detail in section d. . . outer z chamber the central outer z chamber (coz) is a drift chamber with wires strung perpen- dicular to the z-axis. it is used to improve the poor z measurement of the cjc and achieved a resolution of about μm. this chamber is installed between the inner and outer jet chambers cjc and cjc and covers the angular range ◦ < θ < ◦. the thickness of the chamber is . % x , where x is the radiation length. energy losses and photon conversions between the jet chambers have to be taken into account for the track reconstruction algorithm. . . forward tracker an additional tracking system (forward tracking detector, ftd) to identify charged particles is installed in the forward direction. this allows the measurement of heavy quark production for large q and x, where the hadronic final state is produced in the forward direction. the detector is designed to detect tracks in the angular range ◦ < θ < ◦ from the interaction point and was upgraded for hera ii. it consists of three supermodules, where the inner two supermodules (with respect to the interaction point) contain five planar chambers (the three inner denoted as p type, the two outer as q type). figure . : r-z view of the upper half of the liquid argon calorimeter. the parts denoted with “e“ belong to the electromagnetic section, the parts denoted with “h” belong to the hadronic section. the different orientation of the absorber plates for the different wheels is visible. the outer supermodule has only one module of type q. the drift cells for the p chambers have four wires each, which are rotated with respect to the y-axis for an amount of ◦, + ◦ and − ◦. the cells for the q type have wires each at angles of + ◦ and + ◦. the identification of tracks in the ftd starts with a search for clusters, which are groups of three or four hits consistent with a straight line, in each of the planar chambers. a cluster defines a plane in space containing the path of the particle. the combination of two planes defines a line segment on the particle’s path. a third plane is required to resolve ambiguities due to many different com- binations of two planes if several particles pass the chamber. these segments from different submodules are combined to forward tracks. it is also possible to combine these forward tracks with tracks from the central drift chamber cjc for the overlap region. . calorimetry . . liquid argon calorimeter (lar) the liquid argon calorimeter (lar) (figure . ) covers the forward and central region of the h detector in the angular range ◦ < θ < ◦. the electromagnetic section (ecal) measures electromagnetic showers using lead absorbers. hadronic showers which penetrate into the hadronic part (hcal) are measured using steel absorbers. in both cases the active material is liquid argon, therefore the whole calorimeter is contained in a cryostat. the calorimeter is divided into eight wheels made of eight octants each. the orientation of the absorber plates is such that par- ticles from the interaction point impinge with an angle larger than ◦. the electro- magnetic section of the calorimeter has a resolution of σe /e ≈ % √ e/gev ⊕ %, the hadronic section has a resolution of σe/e ≈ % √ e/gev ⊕ %. the calorime- figure . : illustation of the electromagnetic spacal: each module, indicated by the thick lines, consists of eight submodules (thin lines). ter is of non compensating type, which means that the response for electromagnetic particles is higher than for hadrons. the compensation is obtained using offline algorithms. . . spacal the backward region of h is instrumented with a lead-scintillating fibre spaghetti calorimeter (spacal). it has a diameter of cm and consists of an electromag- netic (see figure . ) and a hadronic section. the electromagnetic section consists of about quadratic lead absorber cells with scintillating fibres, pairwise arranged in submodules, where eight submodules build a module. the cells have an active volume of × × cm . the thick- ness corresponds to . radiation lengths which ensures an only small leakage of the deposited electromagnetic energy to the hadronic section. the fibres with . mm diameter direct the light through light mixers to photomultiplier tubes (pmt), where the scintillation light is converted into an electrical pulse and amplified. this calorimeter is used to measure the scattered electron in the backward direction, with an energy resolution σe/e ≈ % √ e/gev ⊕ %, and the polar angle of the scat- tered electron can be measured with a resolution of about mrad. in addition this detector is used to trigger on the scattered electron and as a veto to suppress beam gas due to the precise timing information with a resolution of ns. c m cm . mm m m figure . : inner spacal region: the circle shows the new spacal hole, which has a radius of cm. the origin is shifted with respect to the origin of the h coordinate system. the hadronic section of the spacal has a similar structure with larger cells of di- mension × × cm . the cell depth corresponds to one interaction length. this calorimeter is used as a veto against hadrons. the installation of the focussing at h for the hera ii upgrade required modi- fications of the inner spacal region. in order to have space for the new elliptical beam pipe, the radius of the spacal hole was extended cm, where the center is shifted with respect to the center of the h coordinate system (see figure . ). the angular coverage is reduced to ◦ < θ < ◦, the acceptance in q is reduced to ≈ < q < gev . . muon system the return yoke of the solenoid magnet is instrumented with limited streamer tubes to measure tracks of muons that penetrate the calorimeters. this central muon detector (cmd) is divided into four parts: forward endcap ( ◦ < θ < ◦), backward endcap ( ◦ < θ < ◦), and the barrel region ( ◦ < θ < ◦), made of the backward and forward barrel. the backward barrel region is not used for the analysis presented in this thesis. each of these parts consists of modules (see figure . ). about limited streamer tubes with a cross section of × cm are mounted in the slits between the ten iron plates with a thickness of . cm, where the slits are on average . cm wide. three additional layers of streamer tubes are mounted on the inner and outer surface of the return yoke. the wires are strung parallel (perpendicular) to the beam axis for the barrel (endcap) region. influence charges x y z x y z magnet coil backward endcap forward endcapbackward barrel forward barrel figure . : illustration of the four parts of the central muon detector. each part consists of modules. �� z y x h i �� g strips strips and pads pads iron ds layers with pads layers with pads layers with strips layers with strips layers with strips mm mm mm figure . : cross section view of an instrumented iron module. are induced and measured at electrodes mounted at the top side of the chambers. these electrodes are either strips with a width of mm and mm spacing or pads with a size of × cm in the endcaps and × cm in the barrel. the instrumentation of the different layers of a module is shown in figure . . wires and strips are read out digitally and allow for a two-dimensional space measurement. five layers ( , , , and ) are used in addition for trigger purposes. the momentum resolution of the cmd is only about %. therefore for this analysis the muon system is only used to identify muons, the momentum measurement is provided by the tracking system. the tracks from the muon system (iron tracks) are combined with the inner tracks from the tracking system (see section . ). . luminosity measurement the rate at which the bethe-heitler process ep → epγ [ ] occurs, is used to measure the luminosity. this process has a large and well known cross section, calculable in quantum electro dynamics (qed). the photons of this process are detected at small angles by a quartz-fibre calorimeter with tungsten absorber located at z=- m. a beryllium filter shields the detector against synchrotron radiation background induced by the focusing magnets. the main uncertainty of the measurement is the acceptance of the photon detector. the offline measurement for the hera ii running period is not fully understood when writing this thesis. therefore an averaged uncertainty of about % is assumed for the data period analysed in this thesis, which is higher than the uncertainty for hera i, which is about %. . trigger at the nominal bunch crossing rate of mhz at hera, electron proton scattering is expected to appear at a rate of several khz. as the rate of background events (e.g. beam gas and beam wall events) is three orders of magnitude higher and the detector can only be read out at a rate of hz, a trigger system with a high selectivity is required which selects interesting physics events and rejects background event efficiently. at h a four level trigger system was used: the algorithms of the first three levels were running on custom made hardware. the readout of one event takes about . ms, during which the data taking is stopped. the optimisation goal to keep this dead time reasonably low (about %) defined the maximum rate at which the detector can be read out. the computing farm of standard pcs at level four reduced the rate further to about ten events per second which were fully reconstructed and written to tape. . . level the first level trigger is the only trigger level that does not induce deadtime itself, as the data from the subdetectors is written to pipelines and the data taking continues during the calculation of the trigger decision. in total trigger elements (tes) are formed, based on track signals of the muon system and the central tracker and energy depositions in the calorimeters. these tes are forwarded to the central trigger logic (ctl) where they are combined to up to subtriggers (sts). only if a subtrigger condition is fulfilled, the pipelines are stopped and the dead time starts. in order to limit the output rate of this trigger level to the predefined target rate and to make best use of the available bandwidth, subtriggers are prescaled, i.e. scaled down. therefore some subtriggers “see” only a fraction of the luminosity. this is not the case for the subtrigger relevant for the analysis presented in this thesis. subdetectors with precise timing information (spacal and cip) deliver t trigger signals, which define the bunch crossing of the triggered interaction and mark there- fore the positions in the pipelines that has to be read out by the subdetectors. . . level after a positive level decision dead time is accumulated as the pipelines are stopped. the level decision is validated using three trigger systems: the topo- logical trigger and the neural network trigger combine information from trackers, calorimeters and the muon system. the ftt refines the level decision and reaches a track resolution comparable to the offline reconstruction. the total time available for the level decision is μs. trigger elements are forwarded to the central trigger logic and combined. if no level one trigger could be validated by level two, the data taking resumes, otherwise the readout of the detector begins. many level one triggers did not have level two conditions and were validated by default. . . level the readout started after a positive level two decision with an average readout time of . ms per event. this time could be much larger, depending on the event size. the level trigger, which was part of the ftt system (see section d), could stop the readout after μs and therefore reduce the deadtime of the detector. the level system performed a partial event reconstruction based on level two track information on commercial processors. in addition information from the muon system and calorimeter information is used. trigger elements are provided to the central trigger logic, which rejects the event if no trigger element could be validated, where some subtriggers with no level condition are validated by default. the level system must ensure a maximum output rate of about hz. . . level after readout the full event information was assembled at the event builder. the full event reconstruction was performed at a pc farm, followed by an event classification. events are rejected in a deterministic way: for subtriggers with prescale factor n only each n-th positive decision is taken into account. based on this decision events which fall into one of the event classes and in addition a fraction of rejected events were stored with a rate of about - hz. chapter previous experimental results in this section an experimental review about beauty quark production at hera and elsewhere is given. after a short introduction of the experimental methods used for the measurements at the hera experiments, the results are discussed for the photoproduction and the dis region. this is complemented by a discussion of measurements at other colliders. a discussion of charm quark production can be found in [ ]. . experimental methods the different taggig methods used at h and zeus to select heavy flavour enriched samples are illustrated in figure . . a full reconstruction of heavy flavoured hadrons is only done for charmed hadrons, where e.g. the golden decay channel (d∗+ → d π+s → (k−π+)π+s ) is used. for beauty hadrons, no similar decay channel without neutral particles and large enough branching ratios exists. instead usually a lepton tag is used. the muons and electrons from semileptonic decays of beauty hadrons have large enough momenta and can therefore be well reconstructed. for the muon+jet analyses, jets are required in addition to the lepton (dijets for the photoproduction region and only one jets due to the lower statistics for the dis region). the jets estimate the quark direction. this information is needed to determine the fraction of beauty events on a statistical basis using the prelt tag. prelt is the relative transverse momentum of the lepton with respect to the jet axis. the large mass of beauty hadrons is exploited which results in large values of prelt . an event display of a dijet event with an identified muon is shown in figure . . figure . shows the prelt distributions used for the first h measurement [ ], the h measurement using the full hera statistics [ ], and for the analysis presented in this thesis. in [ ] the prelt tag is combined with a lifetime tag which exploits the long lifetime of beauty hadrons. the signed impact parameter distribution δ of a track is defined as the shortest distance to the primary event vertex. to define a signed impact parameter the jet axis is needed. in figure . the δ distribution for the muon track is shown. the position of the muon track at the primary vertex is measured figure . : tagging methods used at h and zeus to select heavy flavour enriched samples (from [ ]). figure . : event display of a dijet event with an muon identified in the central muon detector. h data fit b contrib. c contrib. fake muons m uo ns / . g ev pμ [gev] t,rel p rel t [ gev ] e n tr ie s data bb − cc − uds sum h < q < gev rel t p . . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data [gev] figure . : p relt distribution from the first h measurement [ ] based on pb − from photoproduction data (upper left plot), from the measurement [ ], based on about pb− of dis data recorded in / (upper right plot) and from the measurement presented in this thesis, based on about pb− hera ii data (lower plot). the upper right and lower plot show the distribution for electroproduction data. the increased statistics of the / data and the hera ii data allow the measurement of differential cross sections and double differential cross sections, respectively. - . . . impact parameter δ [ cm ] e n tr ie s data bb − cc − uds sum h < q < gev figure . : δ distribution of the muon track, which is defined as the distance to the primary vertex, for the dis sample of the h muon+jet analysis [ ]. using the innermost tracking detector, the central silicon tracker (see section . . ). this additional information allows a separation of light flavour, charm and beauty events on a statistical basis. this is not possible when using prelt alone, as the light flavour and charm quark distributions are very similar. the main disadvantage of methods using jets is the lower energy cut at about gev, which is necessary to reconstruct a stable jet axis. this cut limits the measured range of the beauty quark transverse momentum. a measurement at threshold is possible when requiring a second heavy quark tag besides the muon, either a d∗ or a second muon. for the d∗ analyses [ , ] the charm and beauty content of the sample can be disentangled on a statistical basis using charge and angular correlations (see figure . ). for the dimuon analyses [ ] it is exploited that for the beauty signal there are significantly more muon pairs with unlike-sign charges. this method has the advantage that low beauty quark momenta can be measured but the disadvantage of a low statistics data sample compared to other methods. an alternative method is the inclusive lifetime tagging method, based on the displaced impact parameter of tracks in dijet events [ , ]. this method has the advantage that highest transverse jet momenta up to gev can be reached, because of the larger available statistics. figure . : possible production of a muon and a d∗ meson in a beauty quark event (from [ ]). . measurements at hera beauty production is measured at hera in photoproduction and deep inelastic scattering by the collider experiments h and zeus using the different methods explained in the previous section and covering different kinematic regions. the largest statistics is available for the photoproduction region. in addition, beauty production was measured at the fixed target experiment hera b. . . photoproduction in figure . a summary of zeus results, based on hera i data, is shown. this includes the very recent results from the analysis using decays into electrons [ ], an older measurement using the same method [ ], the measurement using decays into muons [ , ] and the d∗ muon measurement [ ]. the measured cross sections with respect to the beauty quark momentum are compared to the nlo prediction. for the jet measurements the transverse quark momentum is given by the transverse jet momentum, the lowest momentum is accessible for the d∗ muon measurement. in [ ] it is stated that “the measurements agree well with the previous values, giving a consistent picture of b-quark production in ep collisions in the photoproduction regime and are well reproduced by the nlo calculations”. the interesting region of low transverse momenta will be further explored by an h measurement at threshold using electrons and muons triggered by the fast track trigger [ ]. the nlo prediction predicts a less steep behaviour than the h hera i analysis based on events with muon and jets, which combines prelt tag and the lifetime tag [ ] (see figure . ). the prediction “is lower than the data in the lowest momentum bin by roughly a factor of . ”. when extrapolated to the inclusive beauty quark cross (gev)b t p ( p b /g e v ) b t /d p σ d e→ b - zeus pb μ d* → b zeus - μ → b zeus - e→ b zeus - nlo qcd | < b η| ebx)→ (ep b t /dpσd < gev q . < y < . zeus figure . : summary of zeus photoproduction results, obtained from hera i data. besides the latest results using decays into electrons [ ], the results from [ ], [ , ] and [ ] are given. section, the result is . standard deviations below the result obtained in the first h measurement using the prelt tag [ ]. the analogue zeus measurement [ ] did not verify this result and agrees with the nlo prediction (see figure . ). the higher statistics of the hera ii data and the better understood cst detector allows a measurement of higher precision [ ]. also for the dijet analysis based on the inclusive lifetime tag [ ] the data is above the nlo prediction (see figure . ). . . deep inelastic scattering the beauty production cross section at a median transverse momentum value for the b-quark of . gev was measured as well for deep inelastic scattering in [ ]. it is concluded that “[...] the measured cross sections exceed the nlo predictions, but they are compatible within errors.” some results of the zeus hera i measurement at higher transverse momenta using the prelt tag are shown in figure . . the jet selection is performed in the breit frame (see section . . ). it is concluded that “the differential cross sections are in general consistent with the nlo qcd predictions; however at low values of q , bjorken x, and muon transverse momentum, and high values of jet transverse energy and muon pseudorapidity, the prediction is about two standard deviations below the data.” a similar measurement was performed at h for hera i data, in a more restricted phase space. also for this measurement jets are selected in the breit frame, and in addition to the prelt tag the lifetime tag is used. for this measurement it is concluded that also for dis “the total cross section measurements are somewhat higher than the predictions.[...]the observed excess is pronounced at large muon pseudo-rapidities.” preliminary results for a zeus measurement using a fraction of the hera ii statistics, again using only the prelt tag, are shown in figure . . this time the jet selection is done in the laboratory data nlo qcd ⊗ had nlo qcd cascade pythia h ep → ebb − x → ejjμx q < gev p jet t [ gev ] d σ /d p je t t [ p b /g e v ] figure . : differential photoproduction cross section as a function of the jet trans- verse momentum for the highest transverse momentum jet for the h muon+jets hera i measurement [ ] (left) and the zeus muon+jets hera i measurement [ ] (right). / gev jet t p [ p b /g ev ] je t t /d p σ d - data pythia cascade had⊗nlo qcd ejjx→x b eb→ep / gev jet t p [ p b /g ev ] je t t /d p σ d - data pythia cascade had⊗nlo qcd ejjx→x b eb→ep / gev jet t p [ p b /g ev ] je t t /d p σ d - data pythia cascade had⊗nlo qcd ejjx→x b eb→ep / gev jet t p [ p b /g ev ] je t t /d p σ d - data pythia cascade had⊗nlo qcd ejjx→x b eb→ep h / gev jet t p [ p b /g ev ] je t t /d p σ d - data pythia cascade had⊗nlo qcd ejjx→x b eb→ep h / gev jet t p [ p b /g ev ] je t t /d p σ d - figure . : differential photoproduction cross section as a function of the jet transverse momentum for the highest transverse momentum jet for the h hera i dijet analysis using the inclusive lifetime tag [ ]. - data nlo qcd ⊗ had nlo qcd cascade rapgap h ep → ebb − x → ejμx < q < gev p breit t,jet [gev] d σ /d p b re it t, je t [p b /g e v ] - . . data nlo qcd ⊗ had nlo qcd cascade rapgap h ep → ebb − x → ejμx < q < gev ημ d σ /d η μ [ p b ] figure . : differential cross sections as a function of the jet transverse momen- tum and the muon pseudorapidity for the h hera i dis analysis [ ] using a combination of the prelt tag and the lifetime tag. frame and the measurement was extended to the forward region and supplemented by double differential cross sections. it is concluded that “the total visible cross section is σ higher than the nlo prediction. [...]in all distributions the data are described in shape by the mc and by the nlo qcd calculation.” for the analysis presented in this thesis the well established prelt method is applied to a large fraction of the hera ii data. in comparison to the h hera- analysis, the phase space is extended towards larger pseudorapidities and smaller momenta of the muon and the jet selection is performed in the laboratory frame. as a cross check, the analysis is repeated for the same phase space region as for the hera i anaysis , selecting the jets in the breit frame. . . fixed target fixed target beauty production at hera-b, where the proton beam halo interacts with wires of different materials, allows a measurement at threshold complementary to the collider experiments. the result of a combined measurement based on the decay channels bb̄ → j/Ψx and bb̄ → μμx [ , ] is shown in figure . . the conclusion is that the combined result “is consistent with the latest qcd predictions [...] based on nlo calculations and resummation of soft gluons.” due to the modified spacal detector the lower part of the q phase space is only accessible by an extrapolation based on the monte carlo prediction figure . : differential cross sections as a function of the jet transverse momen- tum and the muon pseudorapidity for the zeus hera i dis analysis [ ] using the prelt tag. (gev)jet t p ( p b /g e v ) je t t /d p σ d - zeus - zeus (prel.) pb rapgap x . nlo (hvqdis) zeus - zeus (prel.) pb rapgap x . nlo (hvqdis) (gev)jet t p ( p b /g e v ) je t t /d p σ d - μη - . - - . . . . ( p b ) μ η /d σ d zeus - zeus (prel.) pb rapgap x . nlo (hvqdis) zeus - zeus (prel.) pb rapgap x . nlo (hvqdis) μη - . - - . . . . ( p b ) μ η /d σ d figure . : differential cross sections as a function of the jet transverse momen- tum and the muon pseudorapidity for the zeus hera ii dis analysis [ ] using the prelt tag. proton beam energy [gev] [ n b /n u cl eo n ] b b σ kidonakis et al. ( ) bonciani et al. ( ) + x)ψj/→e (b + x)μμ→be (b + x)μμ→b + x and bψj/→hera-b (b figure . : cross section for bb̄ production as a function of the proton energy in fixed target collisions. shown is the result of a combined hera b measurement [ , ], lower energy fermilab experiments [ , ] and nlo predictions. . measurements at other colliders . . pp̄ collisions beauty production in hadron collisions was first measured at the spp̄s collider at cern. in [ , ] the ua collaboration finds “good agreement with an [nlo] qcd prediction over the whole measured transverse-momentum range”(figure . left). also this measurement is based on a prelt fit to the muon decay spectrum (see figure . , right). over the last years the tevatron collider is the main source for beauty quark production measurements in pp̄ collisions. the measurements were performed at an centre of mass energy of gev for run i and gev for run ii. for the final run i measurements based on beauty hadron decays, both collaborations, d and cdf, come to the conclusion that the measurements do not agree very well with nlo predictions (see figure . ). for a measurement in the forward region [ ], the d collaboration states that they “find that next-to-leading order qcd calculations underestimate b quark production by a factor of four in this region.” for the measurement [ ] cdf comes to the conclusion that “the differential cross section is measured to be . [...] times higher than the nlo qcd predictions with agreement in shape.” in contrast, a d measurement based on beauty jets [ ] is well described by the nlo qcd prediction. the results of a cdf measurement based on run ii data [ ] are shown in figure . . the data is in good agreement with qcd predictions using a fixed-order approach with a next-to-leading-log resummation, using updated determinations of proton parton densities and beauty quark fragmentation functions. figure . : results from the ua measurement at the spp̄s collider (left) and the prelt distributions used to measure the beauty fraction. figure . : tevatron run i measurements of beauty quark production from d (left) [ ] and cdf (right) [ ]. figure . : recent measurement of beauty quark production from cdf for run ii data [ ]. the data is compared to improved qcd calculations. . . γγ collisions beauty quark production in photon-photon collisions was measured at the lep experiments. the l collaboration published final results based on the whole data sample, where events containing b quarks are identified through their semileptonic decay into electrons or muons [ ]. the result is shown in figure . and compared to nlo qcd predictions. the results are ”found to be in significant excess with respect to monte carlo predictions and next-to-leading order qcd calculations.” the measurement is a factor of three, and three standard deviations, higher than the prediction. figure . : beauty quark production measurement at the lep collider [ ]. the data is compared to nlo qcd calculations. for completeness also measurements of charm quark production are compared to the predictions. chapter event reconstruction this analysis is based on the reconstruction of the scattered electron and the hadronic final state, in particular muons and jets. this will be discussed in this chapter in detail, focussing on the subdetectors and algorithms involved. . identification and reconstruction of the scattered lepton the main detector for measuring the kinematics of the scattered lepton in the kine- matic range of this analysis is the electromagnetic part of the spacal calorimeter. due to the high granularity of the calorimeter, the scattered lepton deposits en- ergy in several neighbouring cells, which comprise a cluster. the cluster having the highest energy is taken as the scattered electron, where only clusters with a minimum energy of gev and a maximal radius of cm are taken into account. the cell energies are calibrated using the double-angle method, which was intro- duced in [ ] and [ ] and has become the standard method to perform the electron calibration [ ]. this method makes use of the fact that the kinematics of the scat- tered lepton is overconstrained and can be determined from the measurement of the hadronic final state. the polar and azimuthal angle of the lepton with respect to the event vertex is determined from the cluster position taking into account the position of the event vertex. in addition tracks measured from the bpc detector are extrapolated to the spacal. if the distance of the track impact point to the cluster centre is smaller than cm, this extrapolated value is used. finally beam tilt corrections are applied. this ensures that the angles are measured with respect to the beam axis which is tilted against the nominal axis. from now on only the term electron is used for electrons and positrons. the radius is defined using logarithmic weighting. the z position of the cluster is not measured directly but calculated from the cluster energy ecl using the formula z = . · ecl + . log( · ecl). the parameters of this formula are determined from simulations of the longitudinal shower distribution. . identification and reconstruction of the muon the reconstruction of the muon kinematics is done using the information from tracks in the inner tracking chambers. the cmd, which is the outermost part of the h detector, is used to identify the muon. muons in the energy range considered in this analysis are minimal ionising particles. in addition they do not produce electromagnetic or hadronic showers in the calorimeters (the average energy loss in lead is only about mev per traversed cm). the energy deposits are concentrated within a narrow cone around the muon track. muons need an energy of about . gev to pass the superconducting coil surrounding the calorimeter and reach the cmd. here they loose an energy of about mev per iron plate. for this analysis only muons are considered whose inner track fulfills certain quality criteria (”lee west tracks”, [ ]) and can be extrapolated and linked to the outer track with a minimal link probability. the latter is derived from the χ value which is determined from the track parameters of both the inner and outer track and their covariance matrices. details concerning this procedure as well as the reconstruction of inner tracks (inner chambers) and outer tracks (cmd) can be found e.g. in [ ]. the track reconstruction will be outlined briefly in the following. . . track reconstruction in the inner drift chambers in the central jet chamber a track finding in the plane perpendicular to the beam axis is perfomed. this track finding is based on charge and drift time information of single hits. triplets of hits are connected to curved tracks using a χ fit. the curvature κ allows the determination of the muon momentum since the magnetic field is known. in the r-z-plane the z-position is determined from the charge division between the wire ends. in addition information from the coz drift chamber is used to increase the resolution. the values determined for the track include the helix parameters κ, θ, φ, and z . θ and φ denote the track direction and z the position at the dca, which is the point of closest approach to the event vertex. after the track reconstruction a vertex fit is performed yielding refined helix parameters. this leads to a momentum resolution of σpt /pt = . pt/gev ⊕ . . track segments of the radial and planar drift chambers of the forward tracking detector are combined to tracks and fitted to the reconstructed vertex. in the overlap region ( ◦ ≤ θ ≤ ◦) a combination of forward and central tracks is performed. . . track reconstruction in the instrumented iron tracks in the central muon detector are searched for using up to wire layers and pad layers (see section . ). a pattern matching is performed separately for the forward and central parts. only patterns with a sufficient hit number and not matching to particle showers are considered as tracks. inner tracks are extrapolated to the cmd, taking into account energy loss, multiple scattering and variations of the magnetic field. then the extrapolated parameters are compared to the parameters measured by the cmd using a χ method. the following parameters of the iron track (outer track) are used: • the z-coordinate of the first point on the iron track • the azimuthal angle of the connection of the first measured point on the iron track to the event vertex • the azimuthal angle of the reconstructed iron track from the χ value a linking probability is determined. events with a low linking probability are rejected (see section . ). . reconstruction of the hadronic final state the reconstruction of the kinematics of the hadronic final state is based on hadronic final state (hfs) objects. these are also input objects to the jet finding al- gorithm (see section . ). the hfs objects are constructed by a energy flow algo- rithm (hadroo [ ]) making use of information from charged particle tracks and calorimetric energy clusters. their respective resolution and overlap are taken into account, while double counting of energy is avoided [ , ]. in the following the selection of input objects to the algorithm and the basic principles of the algorithm will be described. . . selection of input objects input to the algorithm are tracks and clusters. the tracks have to be well measured with the central detectors, see section . for the track reconstruction. tracks are supposed to originate from a pion, the energy is given by e track = p track + m π, ( . ) the error is obtained from error propagation using the output of the track fit: σetrack etrack = etrack √ p t,track sin θ cos θσ θ + σ pt,track sin θ , ( . ) with σpt and σθ being the corresponding errors on pt,track and θ. the other input to the algorithm are clusters. they are built by a clustering al- gorithm from neighbouring cells after applying noise reduction and dead material corrections. clusters can be classified as electromagnetic or hadronic. all clus- ters with at least % of their energy in the electromagnetic part of the calorimeter and with also % of it in the first two layers are defined as electromagnetic clus- ters [ ]. since the lar calorimeter is non compensating, a reweighting of the corresponding cells has to be applied to hadronic clusters. details on the cell selec- tion, clustering and reweighting can be found e.g. in [ ]. finally a noise suppression is applied to the clusters by running several background finders. this includes the suppression of low energy isolated clusters, halo muons, cosmic muons and coherent noise. . . hadroo algorithm the hadroo algorithm is a modified energy flow algorithm in the sense that both track and calorimetric information is used without a one-to-one attribution of tracks to individual clusters. the basic idea of the algorithm is to decide whether the track or the calorimeter clusters behind the track are preferred, i.e. better measured. if the track information is preferred, this information is taken to define the hfs object and the clusters are locked to avoid double counting. tracks are extrapolated to the surface of the calorimeter as a helix, inside the calorimeter a straight line extrapolation is performed. a calorimetric volume is defined by an overlapping volume of a . ◦ cone and two cylinders of radius cm for the electromagnetic part and cm for the hadronic part of the calorimeter. a calorimetric energy ecylinder is defined as the sum of all cluster energies within this volume. the expected relative error on the energy measurement in the calorimeter is estimated, only using the measured track energy, since the contribution of neutral particles to the cluster is not known:( σe e ) lar,exp. = σe,lar,expectation etrack = . √ etrack . ( . ) the track measurement is preferred either if the track measurement is better com- pared to the expected calorimeter measurement, σe,track etrack < σe,lar,expectation etrack , ( . ) or the calorimetric energy is larger than the energy measured from the track, etrack < ecylinder − . · σecylinder . ( . ) in the latter case one assumes calorimetric energy from neutral particles, upward calorimetric energy fluctuations are taken into account. if the track measurement is preferred, clusters behind the track are locked to avoid double counting. the maximum locked energy is given by the calorometric energy ecylinder, also in this case upward energy fluctuations with respect to the track en- ergy are taken into account. if the calorimetric energy is prefered, the hfs object is defined from this energy and the track is locked. the remaining clusters after treating all tracks are considered to be massless. they are assumed to originate from neutral hadrons with no measured track or charged particles with a badly measured track. as discussed in [ ], the calorimetric measurement is better than the track mea- surement in the central region for energies larger than gev. in this detector region the cluster contribution to the total hadronic transverse momentum is about %. . . treatment of calorimetric energy deposition for muons muons are part of the hadronic final state but as minimal ionizing particles subject to a special treatment. an isolation criterium is applied to the muons. a muon is classified as isolated if the calorimeter energy in a cone around the extrapolated track is less than gev, but not larger than pμ + gev. the cone radius is cm in the electromagnetic and cm in the hadronic section of the lar calorimeter. the muon fourvector is not altered, but depending on the isolation the clusters along the muon track in the calorimeter are treated differently. if the muon is isolated, those clusters are locked and are no longer visible for the hfs algorithm. this avoids double counting of energy belonging to the muon. if the muon is not isolated, no locking of clusters is applied. this avoids locking of energy depositions of other particles which would lead to an underestimation of the jet energy. this method results in an overestimation of the jet energy for non isolated muons, which is corrected by applying the same algorithm for the simulated samples. as the calorimetric energy deposition of muons is not described very well the sensitivity of the algorithm to modifications concerning the isolation and locked energy has to be checked. this is described in more detail in section . where an estimation for the systematic uncertainty is given. . jet reconstruction jets on detector level are reconstructed by a jet algorithm, using the hfs objects and the muon as input. jets are complex objects constructed to define and perform the measurement. therefore the results of the measurement and the definition of the cross sections depend on the used algorithm. to correct detector level jets for detector effects like reconstruction efficiencies and to predict cross sections, the algorithm has to be applied on hadron level as well. it is also possible to apply the algorithm on parton level before hadronization corrections to obtain parton level cross sections. the requirement of a sound definition on these different levels implies that the construction of such an algorithm is a non trivial task. the snowmass convention [ ] gives some basic properties such an algorithm has to fulfill. the algorithm has to be well defined on each level. from the experimental point of view the jets have to be easily measured from the hadronic final state. from the theoretical point of view this means that the jets have to be easily calculated from the partonic state. furthermore there has to be a close connection between the jet distributions on detector level and on parton level. the experimental and theoretical requirements the algorithm has to fulfill are closely connected: • the results of the algorithm have to be independent of the detector granularity, this means the angular resolution of the detector. therefore the results should not depend on resolving two particles which are almost collinear. an analogue requirement has to be fulfilled on parton level, the result should not change when replacing one particle by two almost collinear particles. this reflects the fact that in perturbative qcd collinear divergencies are cancelled by virtual corrections. this locking is performed for clusters within a smaller inner cone of radius cm and cm for the electromagnetic and hadronic section, respectively. • the results of the algorithm have to be independent from noise and thresholds of the individual calorimeter cells. the analogue requirement on parton level is the insensitivity to the emission of low energy particles. the resulting infrared divergencies are guaranteed to be cancelled in perturbative qcd by virtual corrections. two types of algorithms are used: • cone algorithms define jets on a simple geometric basis by maximizing the energy flow into a cone with a fixed radius r = √ Δη + ΔΦ , where η is the pseudorapidity and φ the angle position of the particle. algorithms of this type are used for hadron-hadron collisions. despite the advantage of a simple intuitive interpretation and simple implementation, they have several disadvantages. the main problem is the treatment of overlapping jets since the assignment of particles to jets is ambiguous. • clustering algorithms find pairs of particles based on a closeness criteria and merge them to pseudoparticles in an iterative procedure. these pseudoparticles are the constituents of the jets. jets created this way have no geometrical definition but the advantage of an unambigous assignment of particles to jets. algorithms of this type have been used for e+e− collisions and are also used for hadron collisions today after solving problems of the treatment of the hadron remnant and underlying events. the algorithm used for this analysis is the longitudinally invariant kt -clustering algorithm [ ], which will be described in the following section in more detail. . . longitudinally invariant kt -clustering algorithm this is the algorithm most frequently used at hera. it starts with a list of particle fourvectors and proceeds as follows: . for each pair of particles a closeness parameter di,j is calculated, where di,j = min[p t,i, p t,j] [ (ηi − ηj ) + (Φi − Φj) ] ( . ) and for each particle a closeness to the beam particles is defined by di = p t,i. for small opening angles the “distance” di,j is proportional to kt, which is the momentum of the softer particle to the axis of the harder: min[p t,i, p t,j ](ΔΦ + Δη ) ≈ k t . ( . ) . the minimum dmin of all values di, di,j is determined, if dmin = di,j the two particles are combined to form a new one, if dmin = di then that particle is removed from the list and added to the list of protojets. . new values for di, di,j are determined and step is repeated. this iteration continues until all particles are assigned to protojets. the pseudorapidity is defined as η = − ln(tan θ ), where θ is the polar angle of the particle. figure . : quark parton model (left), qcd compton (middle) and boson gluon fusion (right) processes in the breit frame (from [ ]). the way how two objects are merged is defined by the recombination scheme which is a prescription how to calculate the parameters of the new particle from the two merged particles. for this analysis the pt-weighted recombination scheme is used: ηk = pt,k (pt,iηi + pt,jηj ), ( . ) Φk = pt,k (pt,iΦi + pt,jΦj ), ( . ) with pt,k = pt,i + pt,j. ( . ) . . jets in the breit frame in the breit frame [ ] for the lowest order process γ∗q → q′ (quark parton model) there is no energy transfer between the virtual photon and the initial state quark. they collide head on and the quark momentum is reversed (see figure . ). if the z-axis is chosen such that q = ( , , , −q), the incoming quark has the four momentum p = (q/ , , , q/ ) and the outgoing scattered quark has the four momentum p′ = (q/ , , , −q/ ). the transformation to the breit frame requires rotations and a boost and is explained in detail in appendix b. the breit frame is an appropriate frame for the investigation of leading order qcd processes like boson gluon fusion and qcd compton. jets reconstructed from these processes usually have large pt, whereas for quark parton model processes there is no transverse momentum in either the initial or final state on parton level and only limited transverse momentum on hadron level due to fragmentation. despite the advantage of a better separation of bgf processes from qpm processes, the jet selection is performed in the laboratory frame for this analysis. this selection results in a higher statistics event sample and allows a measurement of the beauty contribution to the proton structure function f . the selection of jets in the breit frame is performed as a cross check to compare to published results (see section . ). . kinematic variables this measurement is defined in terms of the properties η and pt of the jet and muon and in addition in terms of the event variables x, q and y which are related via q = x · y · s. the quantities q and y can be determined from the kinematics of the scattered electron, this is called the electron method: ye = − e′e( − cos θe) ee ( . ) q e = e ′ eee( + cos θe) = e′ e sin θe − ye . ( . ) here e′e and θe denote the energy and polar angle of the scattered electron. the resolution of the ye measurement is given by δye ye = ( ye − ) δe′ e′ ⊕ ( ye − ) cot ( θe ) δθe. ( . ) for y > . the resolution is dominated by the resolution of the energy measurement (δe′e/e ′ e < %). due to the /ye term the resolution gets worse for smaller y. one advantage of the hera kinematics is that the measurement of the dis variables is overconstrained and can be performed by using the properties of the hadronic final state alone. when using conservation of energy and longitudinal momentum, (einp − p in z,p ) + (ee − pz,e) = ee = e ′ e( − cos θe) + ∑ a ea( − cos θa), ( . ) y can be expressed in terms of the hadronic final state alone: yh = ee − e′e( − cos θe) ee = Σ ee , ( . ) where Σ = ∑ a ea( − cos θa) and the sum is performed over all final state particles neglecting their masses. this method is called hadron method, it was introduced by jacquet and blondel [ ]. the resolution of y reconstructed by the hadron method is given by the hadronic energy resolution: δyh yh = δΣ Σ . ( . ) this method can also be used for lower values of y since the resolution does not diverge at low y. the reconstruction of y can be further improved. emissions of collinear real photons from the incoming electron before the interaction with the proton (qed initial state radiation) lead to large corrections because in equation ( . ) the electron energy is fixed to ee. this can be avoided by replacing ee by the “measured” incoming electron energy using the relation given by ( . ): yΣ = Σ Σ + e′e( − cos θe) . ( . ) this sigma method [ ] has a similar resolution as the hadron method. yresolution_pfx y gen. . . . . . . . y re c . / y g e n . . . . . yresolution_pfx yresolution q resolution_pfx entries mean . mean y . q gen. [gev ] q re c ./ q g e n . . . q resolution_pfx entries mean . mean y . q resolution figure . : ratio of reconstructed to generated values as a function of the generated value for yΣ (left) and q e (right). to summarize, for this analysis a combination of the electron method and the sigma method is used, q is reconstructed using the electron method and y using the sigma method due to its better resolution at low y and its insensitivity to radiative effects. as a cross check the analysis is repeated using the electron method for the reconstruction of y as well (see section . ). the bjorken scaling variable x is given by x = q e yΣ · s . ( . ) the resolution plots for q e and yΣ are shown in figure . . chapter event selection this measurement is based on the selection of a heavy quark enriched sample where beauty, charm and light quarks contribute with respective fractions of %, % and % [ ]. the exact measurement of the beauty fraction and the determina- tion of detector correction factors applied to the data requires a precise description of the data using simulated monte carlo samples. in the case of discrepancies addi- tional corrections or the introduction of systematic errors have to be considered. this chapter is organized as follows: first the requirements the analysed data sample has to fulfill are discussed, including the online trigger selection and the correspond- ing correction factors. after this the signal and background monte carlo samples are presented. finally the selection cuts that are applied both to the data and the monte carlo samples are discussed in detail, including the selection of dis events, muon events and jet events. control distributions are shown for each selection cut. . data sample data from the years - , taken at a center of mass energy of gev, is analysed. the analysed part of the hera ii data has to fulfill several requirements on the selected runs, the status of subdetectors and the online trigger selection. this will be discussed in the following. the data sample consists of three different run periods, the corresponding run ranges and luminosities are summarized in table . . the total luminosity of the analysed data is . pb− . run period run range luminosity [pb− ] e- - . e- - . / e+ - . table . : different run ranges and corresponding luminosities. s : ((spcle iet> )||spcle iet cen )&&(ftt mul td> )&&veto &&cipveto spcle iet> spacal inclusive electron trigger, outer part spcle iet cen spacal inclusive electron trigger, central part ftt mul td> at least one ftt l track with pt > mev veto veto wall, time of flight detectors cipveto:(cip mul> )&&(cip sig== ) cip veto table . : trigger elements of subtrigger s . . run selection and detector status a run selection is applied to the data, taking into account the running conditions of the machine and the detector. only runs with an assigned quality of good and medium are included in the data sample, in addition several run ranges are excluded due to problems and malfunctions of detector compoments relevant to the analysis. the list of excluded runs is summarized in appendix a. in addition detector status information which is stored every seconds is used. only events where all relevant subdetectors are fully functional are selected. the high voltage status of the sub detectors has to be controlled since a lower than the nominal value leads to a significant loss of efficiency. the relevant subdetectors are the forward and central tracking chambers, the spacal calorimeter, the muon system, the luminosity system, time of flight detectors and the fast track trigger. the condition of the cip detector is not taken into account for the run selection as it is only used as a veto condition. the run ranges and the corresponding corrected luminosites are summarized in table . . . . trigger selection the data sample and its luminosity is defined by the applied online selection crite- rions (trigger condition). the used data sample was triggered by the dis subtrig- ger s , which requires a scattered electron detected by the backward calorimeter (spacal) and in addition a high momentum track measured by the central drift chambers and found online by the fast track trigger. background events origi- nating from beam gas events are rejected online using the timing condition of the spacal and additional veto conditions from the veto wall, different time of flight detectors and cip trigger elements. the subtrigger elements are summarized in ta- ble . . the online selection of dis events is only fully efficient for electron energies above gev. therefore a correction has to be applied for lower energy electrons. the energy dependence of this subtrigger was measured using a sample of events containing an offline selected scattered electron detected by the spacal but trig- gered independently. the fraction of events fulfilling the online spacal condition the given run range for the e− does not include the period before the ftt was active. for this period the track trigger condition is not fully efficient and has to be investigated. e’ [gev] e ff ic ie n c y . . . . . . . effspacal figure . : energy dependence of the spacal trigger efficiency. as well determines the efficiency as shown in figure . . a fermi function of the form /( + exp (−a · e′ + b)), where a and b are free parameters, is fitted to these data points. this additional detector inefficiency was incorporated to the analysis by applying a weight to each simulated event according to the measured electron energy. the online track condition does not lead to an inefficiency. this was checked using an independently triggered data sample. the loss of events due to the additional cip veto condition, which was applied from run on, is negligible. . monte carlo samples the simulated event samples, used to determine detector efficiencies and acceptances and to describe signal and background distributions, are generated using rapgap as the default event generator, supplemented by the heracles program [ ] to gen- erate radiative events. the luminosity of the inclusive event samples, generated using the full mode ipro [ ], including light flavour, charm and beauty events, corresponds to about times the data luminosity (see table . ). the kinematic range for the event generation is restricted to q > gev and y > . . heavy quarks are produced in the massive mode, the decision whether to generate a quark parton model process or a first order αs process is based on the cross section for the particular process at a given x and q . the charm and beauty quark masses are set to . gev and . gev, respectively. the grv lo [ ] sets for the parton density functions are used. the scale is set to q for light flavour events and q + m q for heavy quark production, where mq is the heavy quark mass. lund string fragmentation is used, with the peterson fragmentation function for light quarks and the lund-bowler frag- mc type runperiod number of events l [pb− ] inclusive e− . · ∼ inclusive e− . · ∼ inclusive / e+ . · ∼ beauty e− . beauty e− . beauty / e+ . table . : monte carlo sets: given are the number of events that are reconstructed and simulated and the luminosities for the different run periods. mentation function for heavy quarks (see section . ). due to the large cross section only a fraction of the generated events is simulated: events that do not contain at least one jet with a minimum transverse momentum of gev and a charged parti- cle with transverse momentum of at least . gev in the range ◦ < θ < ◦ are rejected. in total about mio. events are simulated. the luminosity of the beauty event samples, generated using mode ipro [ ], corresponds to about times the data luminosity (see table . ), where the kinematic range is again restricted to q > gev and y > . . the mrst ff lo [ ] set of parton density functions is used. the beauty mass is set to . gev, the scales are set to q + m b and the lund string fragmentation with the lund-bowler fragmentation function is used. also for the beauty sample only a fraction of the generated events is simulated. at least one charged particle with a minimum transverse momentum of . gev in the range ◦ < θ < ◦ is required. no muon is demanded to allow fake muon studies. in total about . mio. events are simulated. . . background sources each selected event requires the detection of a muon candidate. if the muon arises from the decay of a hadron or τ -lepton, but no beauty hadron is produced, the event is regarded as a background event. the muon candidate of a background event may either be a real muon or a misidentified hadron. in the case of a real muon this may come from a charm quark decay or from the decay of a light hadron, usually a pion or a kaon, which are predominantly produced. almost every pion decays into a muon and a neutrino (the branching fraction is almost %). the branching fraction the decay of a kaon into a muon and a neutrino is ( . ± . )% [ ]. due to the large decay lengths cτ ( . m for pions and . m for kaons), these particles are usually stopped inside the lar calorimeter before decaying. because of the abundance of these particles and the large branching fractions, light hadrons that decay during the passage through the detector volume in the inner detector are an important contribution to the background (inflight decays). the other important contribution to the background are misidentified hadrons. this source of background can be further distinguished: • the hadrons that are interacting in the calorimeter do not necessarily deposit their entire energy inside the calorimeter. energy leakage passing some iron layers may lead to the misidentification of these hadrons (denoted as punch through). • hadrons may reach the muon detector without strongly interacting inside the calorimeter volume. the maximum probability for this is . %, depending on the polar angle [ ]. these hadrons contribute to the background because the muon system in some cases falsely identifies the resulting hadronic showers as muons. this contribution is denoted as sail through background. misidentified hadrons (punch through, sail through) and inflight decays are summa- rized as fake muons. according to the monte carlo simulation, for about % of the selected charm events and about % of the selected beauty events, the selected muon candidate is a fake muon, and for about % of the selected light flavour events the selected muon comes from an inflight decay. . z vertex distribution a precise measurement of the kinematic variables and modelling of the detector acceptance requires a well described distribution of the z position of the event ver- tex. the longitudinal bunch structure of the protons is reflected in a gaussian z vertex distribution. a cut on the minimal distance of the z position of the event vertex to the nominal vertex is applied (|zvtx| < cm). events not fulfilling this cut are most probably background events, e.g. due to beam gas interactions. the z vertex distribution is on purpose simulated broader than the data distribution, and the average z vertex position is different for the simulation. the widths and median values of the z vertex distributions are determined from the simulated dis- tributions and summarized in table . . the simulated distributions are reweighted individually for each run period. the reweight factor is determined from the ratio of the gaussian functions obtained from the fits which are evaluated for each event. both the reweighted and non reweighted z vertex distributions are compared to the data distributions in figure . , where all selection cuts as described in the following sections are applied. as for all control plots presented in the following, the beauty fraction is set to %, which is the beauty fraction for the total sample as obtained from the measurement (see section . ). the reweighting leads to an improvement of the description. z vertex [cm] - - n u m b e r o f e v e n ts b mc c+uds mc sum mc data vtxz_xgammabins . < < . z vertex [cm] - - n u m b e r o f e v e n ts vtxz_xgammabins . < < . figure . : comparison of the simulated z vertex distributions to the data before (left) and after (right) reweighting. run period data monte carlo σz [cm] μz [cm] σz [cm] μz [cm] e− . . . . e− . . . . / e+ . - . . - . table . : parameters of the z vertex distributions for the different run periods for data and monte carlo as obtained from a gaussian fit. the monte carlo parameters are determined from the beauty sample which do not differ to the inclusive sample within the errors. . selection of dis events the polar angle of the scattered electron is required to be larger than ◦, ensuring a reconstruction by the backward calorimeter (spacal) and avoiding the overlap region with the lar calorimeter. for efficient triggering the electron energy has to be larger than gev. misidentified electrons, which lead to photoproduction background in the sample, are rejected by requiring a cluster radius smaller than cm because hadronic clusters are usually broader. as shown in figure . the distri- bution is shifted towards smaller values for the simulation, but otherwise described well in shape. possible remaining photoproduction background is rejected by a cut e − pz > gev, with e − pz = ∑ h ea( − cos θa), ( . ) where a summation over the whole final state is done. for photoproduction events, where the scattered electron is not detected but a hadron misidentified as an elec- tron, smaller values of e−pz are measured. the distribution, which peaks at gev due to momentum conservation, is shown in figure . . a loss of hadrons and of photons from initial final state radiation in the backward direction leads to a broad asymmetric distribution. z e-p n u m b e r o f e v e n ts b mc c+uds mc sum mc data [gev] cluster radius [cm] . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : control distributions for e − pz and the cluster radius. for the monte carlo distribution the contribution from beauty quarks is fixed to . %. the e − pz cut applied for the selection is indicated by the dashed line. in addition, several fiducial cuts have to be fulfilled: • in the course of the hera ii upgrade program the beampipe was modified and focussing magnets had to be inserted within the detector region. this implied modifications like a new elliptical shape of the beam pipe and a larger spacal hole, where the center is shifted horizontally with respect to the nominal beam axis and the center of the h coordinate system. at the spacal edge the electron energy and scattering angle cannot be measured correctly since the shower is only partly contained in the spacal. therefore the inner spacal region, which ] [gev q . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data impact radius [cm] n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : q distribution for small values of q and impact parameter distri- bution for the inner spacal region, where the contribution from beauty quarks is fixed to % for the monte carlo distribution. for the q distribution the radial cut is applied, for the impact parameter distribution no lower q cut is applied. the data is compared to the monte carlo simulation. the cuts used for the analysis are indicated as dashed lines. corresponds to low q events, is not very well described by the monte carlo simulation. the shift of the spacal hole leads to an asymmetric acceptance as a function of q . to avoid these problems, a radial cut is applied, and only clusters with a minimal radial distance of cm are accepted . this distance is determined with respect to the intersection of the electron beam with the spacal plane, taking into account a possible beam tilt (beam coordinates) . this ensures a symmetric acceptance and allows for a lower q cut of . gev . the radial cluster distribution and the distribution for low values of q between gev and gev are shown in figure . . both distributions are well descibed by the monte carlo simulation. the loss of acceptance due to the radial cut is clearly visible for the q distribution. no events below . gev pass the selection. to avoid too large correction factors, a lower q cut of . gev is applied. for hera i low q dis analyses a lower cut of gev was usually applied. the analysis is stable with respect to variations of this cut. the radial cut was modified by an amount of ± . cm, the cross section deviation obtained this way is negligible. • a fraction of the inner spacal region is hit by the synchrotron radiation fan of the electron beam. the corresponding cells are taken out of the trigger. therefore these cells are excluded from the selection by applying a box cut which covers the corresponding spacal region. also in this case the coordinates this radial cut is much more conservative than the cut applied in [ ], where the distance of the cluster to the spacal center has to be larger than cm. for that analysis a larger q cut of gev was chosen to ensure a symmetric acceptance. technically this is done by recalculating the position of the cluster using the angular parameters of the scattered electron which are corrected for beam tilts. x [cm] - - - - y [ c m ] - - - - spacal_selection figure . : distribution of the reconstructed impact position of electrons in the spacal plane for data events. no fiducial cuts are applied. the circle and box applied in the selection are shown. additional cell cuts are not shown. due to reconstruction artefacts the shadow of the bpc is visible. for this cut are defined in beam coordinates. • additional cell cuts are applied. some cells do not deliver trigger signals due to electronic problems, others cannot be used for the energy measurement due to a defect photomultiplier. an investigation for these problematic cells for different run periods was done in [ ] and [ ]. all these cells are excluded from the selection. the distribution of impact points for the scattered electron in the spacal plane for data events is shown in figure . . the spacal hole, the area which is taken out of the trigger and the increase of selected events towards the inner region are clearly visible. the radial and the box cut are also depicted. control plots for all relevant distributions are shown in figures . and . . in addition to the dis selection cuts the muon and jet selection cuts as explained in the following sections are applied as well. for all plots the contribution from beauty quarks is fixed to %, as measured from the data (see section . . ). the monte carlo distributions are normalized to the number of data events. the polar angle of the scattered electron is reweighted since the distribution does not in the case of a defect photomultiplier it is demanded that clusters of neighbouring cells have a minimum distance of cm to the defect cell to achieve a good description of the acceptance by the simulation. θe [deg.] c o rr e c ti o n . . . . scatelectheta_xgammabins . < < . figure . : reweight factor applied to the monte carlo simulation as a function of θe. cut value scattering angle θe > ◦ electron energy e′ > gev cluster radius < cm impact radius > cm virtuality . < q < gev inelasticity . < yΣ < . table . : dis selection cuts. the cuts that define the kinematic range of this analyis are in bold letters. describe the data very well. this distribution is reweighted by applying a bin-wise factor that is determined from the comparison of this distribution for data and the inclusive monte carlo sample. this reweighting factor as a function of θe is shown in figure . . this reweighting leads to an improvement for q and e′, as shown in figure . , where all distributions are shown before and after reweighting. in figure . the azimuthal angular distribution of the scattered electron is shown, which is flat and well described by the monte carlo simulation. the y distribution is not described very well for low y (see figure . , left). since this variable is measured from the hadronic final state (see section . ), a reweighting of the pseudorapidity distribution of the muon as discussed in section . leads to a significant improvement (see figure . , right). the log x distribution which is measured from q and y (see section . ) is shown in figure . . also this distribution is well described by the monte carlo simulation. all dis selection cuts are summarized in table . . [gev ] q n u m b e r o f e v e n ts b mc c+uds mc sum mc data [gev ] q n u m b e r o f e v e n ts b mc c+uds mc sum mc data e' [gev] n u m b e r o f e v e n ts b mc c+uds mc sum mc data e’ [gev] n u m b e r o f e v e n ts b mc c+uds mc sum mc data e [deg.]θ n u m b e r o f e v e n ts b mc c+uds mc sum mc data n u m b e r o f e v e n ts b mc c+uds mc sum mc data e [deg.]θ figure . : control distributions for variables determined from the scattered elec- tron. the cuts applied for the selection are indicated as dashed lines. the plots are shown before (left column) and after (right column) reweighting in θe. Σ y . . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data Σ y . . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : control distribution for the variable y, before (left) and after (right) reweighting in ημ. the cuts applied for the selection are indicated as dashed lines. [deg.]φ - - - n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : φ distribution of the scattered electron. log x - - - - - n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : distribution of the bjorken scaling variable. . selection of muons as explained in section , muons have to be identified as iron muons by the outer central and forward muon detector (outer track). this track has to be linked with a certain probability to an inner track measured by the central and forward track- ing chambers. the muon is required to have a minimum transverse momentum of gev, the allowed pseudorapidity range is − . ≤ ημ ≤ , which corresponds to an angular range . ◦ ≤ θμ ≤ . ◦ and is an extension in phase space compared to the previous analysis [ ]. in the overlap region between the central region (cjc) and the forward region (ftd), a small fraction of the selected muon tracks are re- constructed using information from both detectors (combined tracks) or the ftd alone (forward tracks). this fraction is small (about %). in addition, the muon has to be assigned to a jet fulfilling the jet selection criteria as described in the next section. this assignment of muons to jets is an intrinsic property of the used jet algorithm as described in section since every particle is assigned to exactly one jet. in rare cases a second muon is found fulfilling the selec- tion criteria. then the muon having the highest transverse momentum is selected and required to be assigned to a selected jet. the detector cuts applied to the muon have an influence on the efficiency of the muon selection and the purity of the sample. as the kinematic range of this analysis is extended with respect to the pseudorapidity and momentum range of the muon, the influence of these cuts is studied in detail. the studied cuts are the linking probability of the outer to the inner muon track (see section . ) and the number of muon layers having a muon signal separatly for the central and forward region. the linking probability is shown in figure . . for all distributions shown in this section, in addition to the muon selection, the dis selection and the jet selection, as explained in the following section, are applied to data and monte carlo simu- lation. the distribution is flat and increases for small probabilities as expected. the monte carlo simulation describes the data reasonably well. in addition the distribution of background events is shown for the simulated samples and compared to data. background events are defined as misidentified hadrons (fake muons) and real muons coming from inflight decays as defined in section . . . according to the simulation, the background is dominated by misidentified hadrons both from events with no heavy quark or a charm quark involved. the amount of events with a produced beauty quark and a misidentified hadron or events with a real muon coming from an inflight decay is small. as expected, the fraction of background increases for small linking probabilities. the linking probability cut is scanned, the result for the selection efficiency and the purity of the sample is also shown in figure . . the selection efficiency is defined with respect to a sample with no linking probability cut applied. whereas the selection efficiency decreases from % for a linking probability of % to % for a linking probability of %, the fraction of background events stays constant at %. the cut applied for this analysis is at %. the influence of this cut on the cross section is studied as a cross check in section . . the same investigation is done for the cut on the number of muon layers with a cut value transverse momentum pμt > . gev pseudorapidity − . ≤ ημ ≤ . linking probability ≥ % number of muon layers ≥ table . : muon selection cuts. the cuts that define the kinematic range of this analyis are in bold letters. muon signal. the results are shown in figure . for the central region and figure . for the forward region. for this study, no other muon detector cut is applied. the maximum number of layers is , the inner and outer muon boxes (see section . ) are not taken into account. the distributions of the number of layers are not described very well by the simulation because the single hit efficiency is too low for the simulation after a high voltage increase. therefore only a loose cut of at least three muon layers is possible. as can be seen in the plot comparing the efficiency and purity of the sample, no significant reduction of background is possible by using a harder cut, whereas the efficiency decreases significantly from almost % at a cut of at minimum three layers. again the efficiency is defined with respect to a sample with no cut on the number of muon layers applied. the same holds for the forward region. the distribution of the number of muon layers with a muon signal is not described very well, the fraction of events having a signal from less than six layers is negligible. applying a cut on the number of layers does not lead to a significant reduction of the background, whereas the efficiency decreases rapidly. for a cut of less than six layers the background fraction is about %, which is a bit higher than for the central region. another quantity for rejecting background is the number of layers between the first and the last muon layer having a muon signal. this distributions are shown in figures . and . for the forward and central region. again, the distribution for the forward region is well described, the distribution for the central region is not described very well. a cut on this distribution does not lead to any additional background rejection, therefore no cut is applied. the pseudorapidity distribution of the muon is shown in figure . . the fraction of events in the forward region (ημ > . ) is overestimated by the simulation. a reweighting is applied, where the reweighting factors are determined bin-wise from the ratio of the data to the inclusive monte carlo distribution. the reweighting factor as a function of the pseudorapidity is shown in figure . . the polar angle and transverse momentum distributions are shown in figure . . no further reweighting has to be applied, the transverse momentum distribution is well described by the simulation. all cuts concerning the muon selection are summarized in table . . linking probability [%] n u m b e r o f e v e n ts b mc c+uds mc sum mc data linking probability [%] n u m b e r o f e v e n ts data fake muonlinkprobfinebinning_xgammabins . < < . . . . . efficiency fake fraction linking probabiliy [%] figure . : linking probability between central track and iron track: in the upper left plot the data distribution is compared to the simulation, in the upper right plot the data distribution and the distribution from background events as determined from the simulation is shown. in the lower plot efficiency and fake fraction are shown as explained in the text. # muon layers n u m b e r o f e v e n ts �� b mc �� c+uds mc sum mc data # muon layers . . . . efficiency fake fraction figure . : distribution of the number of muon layers with a hit for the central region: in the left plot the data distribution is compared to the simulation, in the right plot efficiency and fake fraction are shown as explained in the text. # muon layers n u m b e r o f e v e n ts �� b mc �� c+uds mc sum mc data # muon layers . . . . efficiency fake fraction nmuonlayersforw_xgammabins_uds . < < . figure . : distribution of the number of muon layers with a hit for the forward region: on the left plot the data distribution is compared to the simulation, on the right plot efficiency and fake fraction are shown as explained in the text. distance muon layers n u m b e r o f e v e n ts b mc c+uds mc sum mc data distance muon layers . . . . efficiency fake fraction figure . : distribution of the distance between first and last hit layer for the central region: on the left plot the data distribution is compared to the simulation, on the right plot efficiency and fake fraction are shown as explained in the text. distance muon layers n u m b e r o f e v e n ts b mc c+uds mc sum mc data distance muon layers . . . . efficiency fake fraction figure . : distribution of the distance between first and last hit layer for the forward region: on the left plot the data distribution is compared to the simulation, on the right plot efficiency and fake fraction are shown as explained in the text. η - - . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data η - - . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : pseudorapidity distribution for the selected muon, before (left) and after (right) reweighting. μη - . . . c o rr e c ti o n . . . . . . . . . muoneta_selection_xgammabins . < < . figure . : reweight factor applied to the monte carlo simulation as a function ημ. φ [deg.] - - - n u m b e r o f e v e n ts b mc c+uds mc sum mc data tp n u m b e r o f e v e n ts b mc c+uds mc sum mc data [gev] figure . : azimuthal angle (left) and transverse momentum (right) distribution of the muon. invariant mass [gev] . . . . e v e n ts masspeak figure . : invariant mass distribution of the elastic j/ψ sample . . muon identification efficiency the performance of the muon identification with respect to the efficiency and misiden- tification depends on the detector cuts applied to the event selection. since the data is corrected for these detector effects using monte carlo simulations, the identifica- tion efficiency of muons in the iron implemented in the simulation has to be checked with real data. correction factors have to be applied to account for a not perfect simulation of the muon identification. a clean sample of muon events is used for this check, the muons origining from decays of elastically produced j/ψ mesons. exactly two well measured tracks are demanded, their invariant mass has to lie within the j/ψ mass window, which is defined as the mass range from . gev to . gev. if in addition at least one of these tracks is identified as a muon in the calorimeter, this event sample is almost background free. the sample was triggered by an in- dependent subtrigger which has no iron muon condition and consists of muon candidates, the invariant mass distribution is shown in figure . . the cuts for se- lecting this sample are summarized in table . . the muon identification efficiency can be checked by considering the second muon. the detector cuts for the iron muon correspond to the final selection cuts discussed in section . the pt dependence of the identification is determined for three detector regions: the forward and back- ward of the barrel region and the forward endcap. for each region the efficiency determined from the data is compared to the efficiency determined from a sample of simulated elastic j/ψ events where the same selection is applied. the results are shown in figures . to . . for each efficiency measurement a fit of a fermi function of the form �(pt) = �max/( + exp (−a x + b)) with three free parameters is performed. the important parameter is �max, which denotes the efficiency for the plateau region. since the fermi function is not able to describe both the low and this sample is generated using the diffvm [ ] monte carlo generator. [gev] t p . . . e ff ic ie n c y . . . . efficiency_forwbarrel °<θ< ° [gev] t p . . . e ff ic ie n c y . . . . efficiency_forwbarrel figure . : muon reconstruction and identification efficiency for the forward barrel determined from data (left) and monte carlo simulation (right). [gev] t p . . . e ff ic ie n c y . . . . efficiency_backwbarrel °<θ< ° [gev] t p . . . e ff ic ie n c y . . . . efficiency_backwbarrel figure . : muon reconstruction and identification efficiency for the backward barrel determined from data (left) and monte carlo simulation (right). high pt part, the fit is only performed for the region with pt > . gev. only muons in this region are used for this analysis. in general, the efficiency is overestimated by the simulation. it is assumed that the reconstruction efficiency is the same for muons from elastic j/ψ decays and muons in a jet environment. the pt dependent correction function is given in figure . . the correction factor is in the range from − % to − % for the backward part of the barrel region and from − % to + % for the forward part of the barrel region. for the forward end- cap a constant correction factor of % is used for the region p > gev which corresponds to pt > gev. the monte carlo simulation is corrected by applying these correction factors. technically this is done by applying a momentum depen- dent reweighting of the simulated events for each of the three investigated detector regions. the results of this investigation are summarized in table . . the limited statistics of the data sample, especially in the high momentum region, leads to a non negligible systematic uncertainty introduced by this method. this uncertainty is estimated by the relative error of the parameter �max determined from the fit. a conservative overall uncertainty of % is estimated for the muon identification. [gev]p e ff ic ie n c y . . . . efficiencyp_forwendcap °<θ< ° p [gev] e ff ic ie n c y . . . . efficiencyp_forwendcap figure . : muon reconstruction and identification efficiency for the forward endcap determined from data (left) and monte carlo simulation (right). [gev] t p . . . . . . c o rr e c ti o n fa c to r . . . . . [ ]/( +exp(-[ ]*x+[ ])) °<θ< ° [gev] t p . . . . . . c o rr e c ti o n fa c to r . . . . . [ ]/( +exp(-[ ]*x+[ ])) °<θ< ° figure . : correction factors for the muon reconstruction and identification efficiencies for the forward barrel (left) and the backward barrel (right). detector region polar angle efficiency rel. correction backward barrel ◦ ≤ θ ≤ ◦ % − % to − % forward barrel ◦ ≤ θ ≤ ◦ % − % to + % forward endcap ◦ ≤ θ ≤ ◦ % + % table . : muon reconstruction and identification efficiencies as determined from data for the different detector regions. also given is the range of correction factors. the efficiency denotes the value �max for the plateau region. elastic j/ψ selection two well measured primary vertex fitted tracks of opposite charge invariant mass . gev ≤ mμμ ≤ . gev one identified muon in the calorimeter (quality ≥ ) ◦ ≤ θμ ≤ ◦, ◦ ≤ θμ ≤ ◦, ◦ ≤ θμ ≤ ◦ |zvtx| < cm table . : cuts for the j/ψ selection. cut value transverse momentum pjett > . gev pseudorapidity |ηjet| ≤ . number of associated particles > table . : jet selection cuts. the cuts that define the kinematic range of this analyis are in bold letters. . selection of jets using the output of the jet algorithm, a muon jet association is performed. the selected muon has to be part of a jet that fulfills the jet selection criteria (denoted as muon jet in the following). the minimum transverse momentum of the jet is gev, the pseudorapidity range is restricted to the detector region |ηjet| ≤ . . to reject possible background from cosmic muons, the number of particles associated to the jet has to be larger than two. the polar angle distribution of the muon jet is shown in figure . , both before and after reweighting of the muon pseudorapidity distribution (see section . ). as expected, also this distribution is well described after the reweighting. in addition, in figure . the transverse momentum distribution, the jet multiplicity distribu- tion and the distribution for the number of associated particles are shown. the transverse momentum distribution is well described, no further reweighting has to be applied. for the jet multiplicity distribution, only jets fulfilling the jet selection criteria (table . ) are counted. the distribution is reasonably well described, the majority of events having one or two reconstructed jets, only a small fraction of events having three reconstructed jets. also the multiplicity distribution of parti- cles belonging to the selected jet is reasonably well described. this measurement relies on a precise understanding of the jet structure. therefore the energy flow of the jets is studied in more detail. the results are shown in figure . . for all selected events of the heavy quark enriched sample, the aver- age transverse momentum summed over all hadronic final state particles close in azimuthal angle (Δφ < ) to the jet axis is determined with respect to the distance in pseudorapidity. in an analogous way this is done for all particles close in pseu- dorapidity (Δη < ) with respect to the azimuthal distance. both distributions are compared to the monte carlo simulation, an excellent agreement for these distribu- tions is achieved. for all the jet control distributions shown, the full event selection including the dis selection and the muon selection was performed. the jet selection cuts are summarized in table . . . summary of the selection all the cuts defining the kinematic range of this analysis are summarized in table . . in total, events are selected. the run dependence of the selection (event [deg.]θ b mc c+uds mc sum mc data n u m b e r o f e v e n ts n u m b e r o f e v e n ts b mc c+uds mc sum mc data [deg.]θ figure . : polar angle distribution for the jet selection. the left plot is before, the right plot after reweighting the pseudorapidity distribution of the selected muon. [gev]tp n u m b e r o f e v e n ts b mc c+uds mc sum mc data # jets n u m b e r o f e v e n ts b mc c+uds mc sum mc data # objects n u m b e r o f e v e n ts b mc c+uds mc sum mc data figure . : transverse momentum of the muon jet (upper left), multiplicity for jets fulfilling the jet selection criteria (upper right) and number of particles belonging to the muon jet (bottom). [rad] - - - > [g e v ] t [ g e v ] t . gev muon pseudorapidity − . ≤ ημ ≤ . jet transverse momentum pjett > . gev jet pseudorapidity |ηjet| ≤ . table . : summary of all selection cuts that define the kinematic range of this analysis. yield) is shown in figure . . no time dependence is observed, the event yield is flat within errors with respect to the run number. on average events are selected per inverse picobarn luminosity. run number · - e v e n ts / p b e- e - / e+ figure . : number of selected events per inverse picobarn luminosity. the dif- ferent run periods are indicated. chapter measurement in this chapter the measurement of the cross section for beauty quark production in deep inelastic scattering is discussed. the measurement of the beauty content of the event sample is presented, followed by a discussion of correction factors that have to be applied to the measured number of beauty events. finally the systematic studies are explained in detail. . cross section definition in this thesis, the cross section is measured for beauty quark production with a muon and a jet in the final state, ep → ebb̄x → ejμx′ in the range . gev ≤ q ≤ gev , . < y < . with pμt > . gev, − . < ημ < and p jet t > . gev. the jets are defined using the kt -algorithm on all final state particles after the decay of charmed or beauty hadrons. muons coming from both direct and indirect b decays (including τ and j/Ψ decays) are considered to be part of the signal. muons from decays of light flavoured hadrons (inflight decays, see section . . ) are regarded as background. . cross section determination in general, the cross section measurement is a counting experiment: the total visible cross section σvisb (ep → ebb̄x → ejμx ′) is determined from the number of measured beauty events for this process, nb, and the luminosity l, nb = l · σvisb . ( . ) for the measurement of bin averaged differential cross sections the number of selected events nb(xi) for each bin xi has to be divided by the bin width Δxi, nb(xi) Δxi = l · Δσvisb Δx |bin i. ( . ) the different variables x investigated in this analysis are q , the scaling variable x, the transverse momentum of the muon and the jet, and the pseudorapidity of the muon. the different binnings for these variables are given in the result tables in appendix c. double differential cross sections are determined in an analogous way nb(xi, yi) Δxi · Δyi = l · Δσvisb ΔxΔy |bin i,j, ( . ) where y is a second variable. in this analysis double differential cross sections are measured as a function of the transverse momentum of the jet for different muon pseudorapidity regions and as a function of log(x) for different q . the measured number of beauty events nb is determined from the number of ob- served beauty events n obsb : nb = n obs b · � − , ( . ) where � is the factor that corrects for the limited acceptance, efficiency and resolution of the detector, for events with muons from inflight decays and not direct or indirect decays, and for events that do not carry a muon at all but are selected due to a misidentified hadron. this correction factor is discussed in section . . the number of observed beauty events n obsb is determined from the total number of observed events n obs by measuring the fraction of beauty events fb for the event sample: n obsb = n obs · fb ( . ) this measurement is discussed in the following section. . measurement of beauty fractions the main experimental challenge of this analysis is the measurement of the fraction of selected events originating from decays of beauty mesons. the cross produc- tion rates of light, charm and beauty quarks at hera roughly scale like σ(uds) : σ(charm) : σ(beauty) = : : . beauty production is strongly suppressed due to the limited kinematic phase space and the smaller electric charge of the down type beauty quark compared to the up type charm quark. when requiring a high pt muon, heavy quarks are enriched, the ratio is then about σ(uds) : σ(charm) : σ(beauty) = : : . light flavour events still give a large contribution to the sample due to the large cross section for light quarks. to measure the beauty fraction, a statistical method is used, based on a fit of tem- plate distributions derived from monte carlo simulations to the data. only the transverse momentum distribution of the muon with respect to the jet axis prelt as an input for this method. in the following, the definition of the variable used to determine the beauty fraction is presented, the statistical method is discussed and the fit results are presented. for the cross section plots the bin averaged cross sections are denoted as dσ dx and shown at the middle of the bin. no bin-centre correction is performed. this ratio was determined in [ ], where the charm and beauty fractions could be disentangled, which is not possible for this analysis (see section ). rel t p . . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data [gev] . . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data rel t p [gev] figure . : prelt distribution for the selected events shown in linear (left) and logarithmic (right) scale, compared to the simulation, which is the sum of the two template distributions, weighted according to the fit result. the fraction of the beauty sample as obtained from the fit is . %. [gev]rel t p . . . . . n u m b e r o f e v e n ts ptreltrack_xgammabins . < < . [gev]rel t p . . . . . n u m b e r o f e v e n ts ptreltrack_xgammabins . < < . figure . : shown is the prelt distribution for the highest momentum track with respect to the jet axis for a sample with no muon requirement, compared to the simulation shown in linear (left) and logarithmic (right) scale. . . relative transverse momentum the transverse momentum of the muon with respect to the jet axis is determined as follows: prelt = |pμ × (pjet − pμ)| |pjet − pμ| ( . ) following the procedure adapted in the previous analysis [ ], the muon momentum is subtracted from the jet momentum. the alternative definition of this variable where the muon momentum is not subtracted is discussed in section . in the context of the systematic studies. the difference in the fit results for both methods is the major contribution to the systematic uncertainty of this analysis. the measured distribution of prelt is shown in figure . together with the monte carlo predictions. the beauty fraction is set to % which is the result of the fit of the different template distributions to the data. this method is only valid if the contribution from light quark events, which are mainly misidentified hadrons, is well described. this is indeed the case, as shown in figure . . for this check a light quark sample was selected by omitting the muon requirement. in this case prelt is defined as the transverse momentum of the highest momentum track with respect to the jet axis, analogue to ( . ). . . binned likelihood fit the prelt distributions for the different monte carlo sources are used as templates to determine the fraction of beauty events in the data. since the shapes of the distributions are not given by a smooth function, the data as predicted from the simulation has to be binned and a binned likelihood fit has to be performed where the distributions for each bin content is assumed to be a poisson distribution both for data and simulation. for this analysis an extended method is used as proposed in [ ] where as an additional degree of freedom for each template component also fluctuations of the number of simulated events are taken into account. this is necessary if the monte carlo statistics is limited which is the case for this analysis. in addition, this method is applicable for monte carlo templates with empty bins and weighted monte carlo templates. the implementation used for this anlysis is provided by the root analysis package [ ] and uses the minuit minimization library [ ]. in the following a short outline of this fit method is given. when using m templates, the number of events in bin i as predicted from the simulation is fi = m∑ j= pjaji, ( . ) where pj are the strength factors one is interested in and aji are the number of monte carlo events from source j in bin i. assuming a poisson distribution for the bin contents, the logarithm of the likelihood is given by ln l = n∑ i= di ln fi − fi, ( . ) where di is the number of measured events in bin i, and n is the number of bins. to take into account fluctuations of the number of monte carlo events, the number of data events in a bin is not given by equation . , but fi = m∑ j= pjaji, ( . ) the actual fractions pj are obtained when considering the normalization of the template samples with nj events to the data sample with nd events: pj = pj nj /nd. where aji is the unknown expected number of events for source j in bin i. the corresponding likelihood that has to be maximized is ln l = n∑ i= (di ln fi − fi) + n∑ i= m∑ j= (aji ln aji − aji). ( . ) this method results in one additional free parameter aji for each template bin in which one is not interested in. a simplification is possible by solving the m differentials of equation ( . ) with respect to pj in an interative procedure. for each step of the iteration and given values for pj , a set of n equations di − ti = ∑ j pj aij + pjti , ( . ) is solved for ti. the new values of aji for the next step of the iteration are then given by the relation aji = aji + pjti . ( . ) this method has the advantage that it can also be used for reweighted monte carlo distributions. this is important for this analysis for several reasons, including the study of systematic effects (see section . ). in this case eqs. ( . ) and ( . ) have to be modified by di − ti = ∑ j pj wjiaji + pj wjiti ( . ) and aji = aji + pjwjiti , ( . ) where wji is the average weight for source j in bin i. . . fit results the prelt distributions obtained from the beauty monte carlo sample and the in- clusive monte carlo samples are used as input templates to the fit procedure as described above. although this method is sensitive to the amount of light quark events, it is not able to distinguish the charm and the light quark fractions. there- fore the fit is performed using two input templates, the beauty template sample and the charm/light quark template. the latter template is based on the inclusive sample where the events originating from beauty quarks are removed. in this way a monte carlo dependency is introduced, since it is assumed that the ratio of events originating from light quarks and charm quarks is correctly described. the shapes for the light and charm quark distribution are compared in figure . . the light to obtain this average weight for each bin, a template histogram with no weights applied to the events is filled. the average weight for a bin is then given by the ratio of entries for the weighted and unweighted template. [gev]rel t p . . . . . n u m b e r o f e v e n ts ptrel_xgammabins_cincl . < < . uds c figure . : comparison of the prelt shape for light and charm quark events. quark distribution has a slightly more pronounced tail for high prelt . the corre- sponding systematic uncertainty, which is of the order of the statistical uncertainty of the fit, is discussed in section . . the fit yields a fraction of % beauty events for the selected data sample, which is measured with a statistical relative uncertainty of %. the statistical error of the fit is the major contribution to the statistical uncertainty. as expected, the statistical error is larger for the differential measurements. due to the reduced statistics of both data and simulated samples the error reaches values up to %, which is com- parable to the total systematic uncertainty of this measurement (see section . ). the fractions and corresponding values for χ obtained from the fit for the different binnigs are shown in figures . and . . for most bins, the χ value (per degree of freedom) is between and . to check the stability of the fit, the number of bins is modified from bins to and bins. no deviation of the fit result within the errors and the fit quality is observed. the main features of the beauty fraction measurement are as follows: • the dependency on q and log x is flat within the errors. • a strong dependency on the transverse muon momentum is observed, the mea- sured beauty fraction increases towards higher momentum and reaches a maxi- mum value of about %. this is expected as the light quark cross section rises very fast towards low jet transverse momenta, whereas the rise is slower for heavy quarks due to their mass. this momentum dependence is reflected in the measurement with respect to the transverse jet momentum. the prelt -spectra for data and monte carlo for the different bins of the muon transverse momentum are shown in figure . . • the measurements show a dependency on the polar angle of the muon. the background contribution to the selected sample is highest for the central region of the detector and decreases towards the forward region. this can be explained by the fact that the amount of material the hadrons have to traverse is lowest for the central region. [gev ] q b e a u ty fr a c ti o n . . . . bfractions_myq bins ] [gev q /n d f. χ . . . . . . . . . fitchi _myq bins logx - - . - - . b e a u ty f ra c ti o n . . . . bfractions_mylogxbins logx - - . - - . /n d f. χ . . . . . . . . fitchi _mylogxbins [gev]μ t p b e a u ty f ra c ti o n . . . . bfractions_mymuonptbins [gev]μ t p /n d f. χ . . . . . . . fitchi _mymuonptbins figure . : results of the prelt fits (left column) and the corresponding χ /ndf. (right column) for the different analysis intervals. to summarize, the prelt method gives stable results with small errors and very good χ values for the fit. this justifies the use of this variable for a one dimen- sional fit without additional lifetime information. nevertheless a large dominating systematic error has to be applied due to a possible bias of this method (see section . ). μη - . . . b e a u ty f ra c ti o n . . . . bfractions_mymuonetabins μη - . . . /n d f. χ . . . . . . . . fitchi _mymuonetabins [gev]jet t p b e a u ty f ra c ti o n . . . . bfractions_mymuonjetptbins [gev]jet t p /n d f. χ . . . . . . . fitchi _mymuonjetptbins figure . : results of the prelt fits (left column) and the corresponding χ /ndf. (right column) for the different analysis intervals. [gev]rel t p . . . . . n u m b e r o f e v e n ts b mc c+uds mc sum mc data .
. gev • − . < ημ < • pjett > gev • |ηjet| < . yields a cross section of σvis(ep → ebb̄x → ejμx′) = . ± . (stat.) ± . (sys.) pb. ( . ) the uncertainty of the measurement is dominated by the systematic uncertainty of about % which is approximately three times larger than the statistical uncertainty. this measurement is compared to predictions from the rapgap and cascade monte carlo programs. the prediction from rapgap is σrap gapvis (ep → ebb̄x → ejμx ′) = . pb, ( . ) from cascade σcascadevis (ep → ebb̄x → ejμx ′) = . pb. ( . ) the rapgap monte carlo prediction is about σ lower than the measurement, the cascade monte carlo prediction is about . σ lower. the prediction from the nlo calculation, corrected to hadron level, is σn lovis (ep → ebb̄x → ejμx ′) = . + . − . pb. ( . ) this prediction is compatible with both monte carlo predictions, but about . σ lower than the data. . differential cross sections differential cross sections are determined in bins of the transverse momentum of the muon and jet, pseudorapidity of the muon, q and log x and compared to the nlo and monte carlo predictions in the following sections. the measured cross sections and nlo predictions are given in appendix c. . . comparison to nlo prediction the nlo prediction lies below the data for most of the measured bins, with the difference at most to σ. a steep rise towards small q is measured (see figure . ). the nlo prediction for the lowest bin is compatible with the data, but the shape of the distribution is not described very well. the deviation of the prediction to the data increases towards higher q , with about . σ difference for the highest bin. the differential cross section as a function of the scaling variable x is shown in figure . , the shape of the distribution is described reasonably well, the prediction is below the data for most of the bins. the cross section as a function of the pseudorapidity of the muon is shown in figure . . the cross section rises towards the forward region and falls for the most forward bin. the rise of the cross section is not described by the prediction. the differential cross sections as a function of the muon and jet transverse momentum fall steeply towards higher transverse momenta. the data show a steeper behaviour than the predictions, with a difference of about σ for the lowest bins. ] [gev q ] [ p b /g e v /d q σ d - hera ii nlo hadronlevel ] [gev q ] [ p b /g e v /d q σ d - xsection_myq bins figure . : differential born level cross section as a function of q . the data is compared to the hvqdis nlo prediction. log x - - . - - . /d lo g x [ p b ] σ d hera ii nlo hadronlevel log x - - . - - . /d lo g x [ p b ] σ d xsection_mylogxbins figure . : differential born level cross section as a function of log x. the data is compared to the hvqdis nlo prediction. μη - . . . [ p b ] μ η /d σ d hera ii nlo hadronlevel μη - . . . [ p b ] μ η /d σ d xsection_mymuonetabins figure . : differential born level cross section as a function of ημ. the data is compared to the hvqdis nlo prediction. [gev]μ t p [ p b /g e v ] μ t /d p σ d hera ii nlo hadronlevel [gev]μ t p [ p b /g e v ] μ t /d p σ d xsection_mymuonptbins figure . : differential born level cross section as a function of pμt . the data is compared to the hvqdis nlo prediction. [gev]jet t p [ p b /g e v ] j e t t /d p σ d hera ii nlo hadronlevel [gev]jet t p [ p b /g e v ] j e t t /d p σ d xsection_muonjetptbins figure . : differential born level cross section as a function of pjett . the data is compared to the hvqdis nlo prediction. ] [gev q ] [ p b /g e v /d q σ d - hera ii rapgap x . cascade x . xsection_myq bins figure . : differential born level cross section as a function of q . the data is compared to rapgap and cascade monte carlo predictions. . . comparison to monte carlo prediction the cross section measurements are compared to the predictions of the rapgap and cascade monte carlo generators (see figures . - . ). the predictions are scaled with a factor . and . for rapgap and cascade respectively. the scaling factors are determined from the predictions and measurements for the total visible range. with exception of the lowest q bin, where the scaled prediction is below the data, all distributions are well described in shape by the predictions. both rapgap and cascade describe the steep rise of the cross section towards small transverse momenta (see figure . ). the rise of the cross section towards the forward direction of the muon is better described by the cascade prediction (see figure . ). log x - - . - - . /d l o g x [ p b ] σ d hera ii rapgap x . cascade x . xsection_mylogxbins figure . : differential born level cross section as a function of log x. the data is compared to rapgap and cascade monte carlo predictions. μη - . . . [ p b ] μ η /d σ d hera ii rapgap x . cascade x . xsection_mymuonetabins figure . : differential born level cross section as a function of η. the data is compared to rapgap and cascade monte carlo predictions. [gev]μ t p [ p b /g e v ] μ t /d p σ d hera ii rapgap x . cascade x . xsection_mymuonptbins figure . : differential born level cross section as a function of pμt . the data is compared to rapgap and cascade monte carlo predictions. [gev]jet t p [ p b /g e v ] j e t t /d p σ d hera ii rapgap x . cascade x . xsection_mymuonjetptbins figure . : differential born level cross section as a function of pjett . the data is compared to rapgap and cascade monte carlo predictions. . double differential cross sections to clarify the measurements of the cross sections as a function of the jet transverse momentum, the measurement is performed double differentially for three regions of the muon pseudorapidity: • − . < η < • < η < . • . < η < in addition the differential cross sections with respect to log x are measured for five q ranges: • . < q < gev • < q < gev • < q < gev • < q < gev • < q < gev the results are tabularized in appendix c and compared to the theory predictions in the following sections. . . comparison to nlo predictions in figure . the measurements as a function of the jet transverse momentum are compared to the nlo prediction for three different bins of the muon pseudorapidity. whereas shape and normalization are well described for the central region, the steep rise of the cross section for the forward region is not predicted by the nlo calculation. the prediction lies below the data with a difference of about . σ for the lowest bin of the jet transverse momentum, but agrees within errors for large jet transverse momenta. the measurements as a function of the scaling variable x are compared to the nlo prediction for five different bins of q . in general the prediction is too low, with a deviation of at most . σ. [gev]jet t p [p b /g e v ] η μ d j e t t /d p σ - hera ii nlo hadronlevel [gev]jetp [p b /g e v ] d j e t t d - - . <η< [gev]jet t p - [gev]jetp - [p b /g e v ] η μ d j e t t /d p σ [p b /g e v ] d j e t t d <η< . [gev]jet t p - [gev]jetp - [p b /g e v ] η μ d j e t t /d p σ [p b /g e v ] d j e t t d . <η< figure . : double differential born level cross section as a function of pjett for three different ranges of the muon pseudorapidity. the data is compared to the hvqdis nlo prediction. log x - - . - . - . ] [p b /g e v σ /d lo g (x )d q d hera ii nlo hadronlevel log x - - . - . - . . . gev • − . < ημ < . • pjet,breitt > gev • |ηjet| < . is σbreitvis (ep → ebb̄x → ejμx ′) = . ± . (stat.) ± . (sys.) pb. ( . ) only about half of the events compared to the laboratory frame analysis are selected, leading to a higher statistical uncertainty of . %. the same systematic uncertainty of % is assumed. the result of this measurement is % higher than the rapgap monte carlo prediction, corresponding to a deviation of about σ. the differential cross sections and the comparison to the rapgap monte carlo prediction are shown in figure . . the rapgap prediction is scaled by a factor of . to account for the normalization difference. the shapes of all differential distributions are reasonably well described by the monte carlo prediction, no significant deviations are observed. this breit frame measurement is compared to the published h measurement by extrapolating the cross sections from the kinematic range q > . gev to q > gev using the monte carlo prediction. the measured total cross section is scaled up by %, yielding σbreitvis (ep → ebb̄x → ejμx ′) = . ± . (stat.)± . (sys.)± . (extrapol.) pb ( . ) for the kinematic range • < q < gev • . < y < . • pμt > . gev • − . < ημ < . • pjet,breitt > gev • |ηjet| < . . the statistical error is . % and a systematic uncertainty of % as determined in the laboratory frame analysis is assumed. the uncertainty in the extrapolation due to the limited monte carlo statistics is taken into account by an additional uncertainty of . % on the measurement. the result quoted in the publication is σ breit,publication vis (ep → ebb̄x → ejμx ′) = . ± . (stat.) ± . (sys.) pb. ( . ) this new hera ii measurement is in good agreement with the published result. the systematic uncertainty of this measurement is of comparable size and the statistical uncertainty is reduced due to the larger data sample. the differential cross sections are compared in figure . . also in this case a scaling factor is applied for each individual bin according to the monte carlo prediction. all new hera ii data points agree even within statistical errors with the published results, except for the most forward bin of the muon pseudorapidity. a deviation of about σ suggest an upward fluctuation of the hera i measurement. the lowest bins of the muon and jet transverse momenta are systematically lower for the new measurement but still in agreement within errors. ] [gev q ] [p b /g e v /d q σ d - hera hera log x - . - - . - - . /d lo g x [p b ] σ d hera hera η μ - . . [p b ] η /d σ d hera hera [gev] t p [p b /g e v ] t /d p σ d hera hera [gev] jet t p [p b /g e v ] je t t /d p σ d hera hera figure . : comparision of double differential cross sections measured in the breit frame to the published hera i measurement. only the statistical errors are shown. for better visibility, the data points of the hera i measurement are shifted horizontally. ] [gev q ] [ p b /g e v /d q σ d - data hera rapgap x . xsection_myq bins log x - - . - . - . - . - - . - . - . - . /d lo g x [ p b ] σ d data hera rapgap x . xsection_mylogxbins μη - . - . - . . . . . [ p b ] μ η /d σ d data hera rapgap x . xsection_muonetabins [gev]μ t p [ p b /g e v ] μ t /d p σ d data hera rapgap x . xsection_muonptbins [gev]jet t p [ p b /g e v ] j e t t /d p σ d - data hera rapgap x . xsection_mymuonjetptbins figure . : comparision of double differential cross sections measured in the breit frame to the rapgap monte carlo prediction. chapter summary and discussion of the results in this analysis, open beauty quark production in deep inelastic scattering with a muon and a jet in the final state was measured with the h detector using approxi- mately pb− of hera ii data taken in the years - . the beauty fraction of the event sample was determined on a statistical basis using the prelt method which exploits the large transverse momentum with respect to the jet axis of the muon for beauty quark events. the phase space was extended to the forward region and lower transverse muon momenta compared to the previous h analysis [ ]. all relevant systematic uncertainties were reevaluated, and the detector cuts of the muon system were optimized to obtain a high selection efficiency and a small background contri- bution to the sample. for the visisble range . < q < gev , . < y < . , pμt > . gev, − . < ημ < , pjett > gev and |ηjet| < . where the jet is reconstructed us- ing the inclusive kt algorithm and selected in the laboratory frame, the total cross section was measured to be σvis(ep → ebb̄x → ejμx′) = . ± . (stat) ± . (sys.) pb. ( . ) the total uncertainty of the measurement was reduced compared to the previous measurement from about % to % due to the higher statistics of the data sample. the statistical uncertainty was reduced from % to . %. therefore it was also possible to obtain the same systematic uncertainty of % although no additional lifetime information as in the previous analysis was used. the results are compared to theory predictions. the prediction of the next-to- leading order calculation in the massive scheme, using the program hvqdis, cor- rected to hadron level, is σnlovis (ep → ebb̄x → ejμx ′) = . + . − . pb, ( . ) with a much larger uncertainty than the measurement, dominated by scale uncer- tainties. this prediction is about . σ below the measurement, which is compatible with the findings of the previous h and zeus measurements in dis. due to the large beauty mass one would expect a much better agreement. the predictions of the monte carlo programs rapgap and cascade, which cal- culate the matrix element in leading order in the massive scheme (augmented by parton showers) and use different parton evolution schemes, are compatible with the nlo prediction. the normalization factors are . and . for rapgap and cascade respectively. differential cross section measurements are performed as a function of q , bjorken x, the muon pseudorapidity, and the muon and jet transverse momenta. for the for- ward direction, at large pseudorapidities of the muon and large bjorken x, and small muon and jet transverse momenta, the next-to-leading order prediction is up to σ below the data. the rise of the cross section towards small transverse momenta is steeper than that predicted by the calculations. these results are compatible with the h and zeus hera i measurements and the latest zeus hera ii results (see figures . and . ). the interpretation is not clear: possible explanations for this deficiency being missing higher order effects or insufficient modelling of the frag- mentation process. the next-to-leading order calculation does not describe the shape of the q dis- tribtion very well for the small and medium q region covered in this analysis. the prediction is below the data for all bins of this measurement. this is also ob- served in the latest zeus measurement, which covers an extended q region up to gev (see figure . ). the prediction agrees only for q much larger than m b and p t . this may indicate that the interplay of the different scales is not fully understood. with exception of the lowest q bin, both monte carlo generators describe the shape of all measured distributions very well. the rise of the cross section as a function of the muon pseudorapidity is better described by the cascade monte carlo. the large statistics of the data sample allowed a measurement of double differ- ential distributions. the measurement of the cross section as a function of the jet transverse momentum for three regions of the muon pseudorapidity confirms that the excess at low transverse momenta is most significant in the forward region, where the next-to-leading order calculation predicts a less steeper rise of the cross section towards small transverse momenta. the prediction is about σ below the data. in contrast, both monte carlo generators describe the shape of the distributions very well for all detector regions. additionally a double differential measurement of the cross section as a function of the scaling variable x is performed for different q regions. with exception of the lowest q region (which is compatible with the single differential q measurement), the shape of the distribution is well described by the prediction for all other q ranges. as a cross check, the measurement is repeated with the reconstruction and selec- tion performed in the breit frame. this allows a direct comparison to the previous [gev]μ t p [ p b /g e v ] μ t /d p σ d hera ii nlo hadronlevel [gev]μ t p [ p b /g e v ] μ t /d p σ d xsection_mymuonptbins zeus ep→ ebb – x→ e μ x zeus (prel.) hera ii pb- hvqdishvqdis pt μ (gev) d σ /d p tμ ( p b /g e v ) data nlo qcd ⊗ had nlo qcd cascade rapgap h ep → ebb − x → ejμx < q < gev pμt [gev] d σ /d p μ t[ p b /g e v ] figure . : cross section measurements as a function of the muon transverse momentum. shown are the results of the analysis presented in this thesis (upper left), of the latest zeus hera ii measurement using decays into a muon and a jet [ ] (upper right), and of the previous h (lower left) [ ] and zeus (lower right) [ ] hera i measurements. μη - . . . [ p b ] μ η /d σ d hera ii nlo hadronlevel μη - . . . [ p b ] μ η /d σ d xsection_mymuonetabins - . . data nlo qcd ⊗ had nlo qcd cascade rapgap h ep → ebb − x → ejμx < q < gev ημ d σ /d η μ [ p b ] figure . : cross section measurements as a function of the muon transverse mo- mentum. shown are the results of the analysis presented in this thesis (upper) and of the previous h (lower left) [ ] and zeus (lower right) [ ] hera i measurements. ] [gev q ] [ p b /g e v /d q σ d - hera ii nlo hadronlevel ] [gev q ] [ p b /g e v /d q σ d - xsection_myq bins - - - - zeus ep→ ebb – x→ e μ xep→ ebb – x→ e μ x zeus (prel.) hera ii pb- hvqdishvqdis q (gev ) d σ /d q ( p b /g e v ) figure . : cross section measurements as a function of q . shown are the results of the analysis presented in this thesis (left) and of the latest zeus hera ii muon+jet measurement. [ ] (right), which covers a larger q region. h results and requires only an extrapolation to lower q . for the total and differ- ential cross section measurements, both analyses agree within the statistical errors. chapter outlook the measurements presented in this thesis are another step towards a better under- standing of beauty quark production at hera in deep inelastic scattering. from the experimental point of view, the high statistics and precision of the hera ii data, which will remain the last ep-data for the next few decades, has not yet been fully exploited. whereas a combination with hera i data and the inclusion of the run pe- riod of hera ii will not lead to a significant increase of the statistical precision of the measurement, there is still potential to decrease the systematic uncertainties (compared to the hera i measurements). the next step in this direction would be the additional use of lifetime information. the cst tracking detector is very well understood and delivered high precision data for a large fraction of the hera ii run period [ , ]. although additional sources of systematic uncertainty have to be considered, it is possible to reduce the total systematic uncertainty of the measurement by combining both prelt and lifetime information and perfoming a two- dimensional fit to determine the beauty fraction. as an estimation of the charm and light quark content of the event sample is possible when lifetime information is used, the measurement of the contribution from light quark events is possible which allows a reduction of the model uncertainties. furthermore, a measurement of charm quark cross sections is possible in parallel. the results of this and other analyses show that the forward region (defined by the proton direction) is the most interesting phase space region to study. due to the limited acceptance of the cst detector, lifetime information is not available for this region and one has to rely on the prelt information alone. despite the stability of this method and the good agreement between the results obtained from both meth- ods [ ], it is necessary to get an understanding of the remaining deficits in the modelling of the prelt distribution, which were seen in this analysis. a step in this direction would be a detailed study of the jet axis resolution for different detector regions. besides a reduction of the systematic uncertainties, a further extension of the mea- sured phase space region is possible. by extending the measurement to regions where the scattered electron is located in the central region, the large q domain can be investigated. as the momentum transfer is much larger than the beauty mass and the transverse momentum of the beauty quark, a comparison to the theory predic- tions in this region allows a better understanding of the multi scale problem. it was shown in this analysis that the double differential measurement is possible due to the high statistics of the data sample. it has to be investigated whether the precision is sufficient to contribute to the measurement of the beauty quark structure function f b , which depends on the double differential cross sections as a function of the scaling variable x and q . as the uncertainties of the theoretical predictions are large compared to the system- atic uncertainties of the measurements, also from the theory side further progress is needed to complete the picture of beauty quark production. it would be interesting to compare the data to next-to-leading order predictions. this mc@nlo [ ] is not available at present. next to next to leading order calculations (nnlo) are available from the mrst [ ] group in the mixed flavour number scheme, but there are no programs existing yet for calculating single or double differential cross sections. the focus of interest in high energy physics will move to the lhc (large hadron collider) at cern very soon, which is expected to discover new physics beyond the standard model. nevertheless, the interpretation of the new data relies on a good understanding of standard model processes, in particular the production of heavy quarks. this is where the legacy of hera, which has delivered the last data on electron-proton scattering for the next decades, will contribute to the exploration of the new energy frontier. appendix a run selection run range reason ftt problem - ftt timing tests - ftt timing tests - ftt wrongly configured - ftt ro problem - ftt level topologies not loaded - ftt problem (cjc ) - ftt level problems - ftt problem (low efficiency) - ftt ro problem - ftt ro problem - ftt problem (low efficiency) - ftt problem (low efficiency) table a. : list of excluded runs mnemonic detector component ftp forward tracker cjc inner jet chamber cjc outer jet chamber lar lar calorimeter ftt fast track trigger lumi lumi system spac spacal calorimeter ironclusters central muon detector tof time of flight system table a. : list of requested detector components for the run selection. the mnemonics as used for the steering of the executable to perform the run selec- tion [ ] are given. appendix b transformation to the breit frame the transformation from the laboratory frame to the breit frame requires rotations and a boost. the complete transformation that contains the boost and rotates the z axis from the laboratory frame to the breit frame can be written in the matrix form l(l → b) = ry(α′)Λ(β)ry (α). (b. ) all components can be written in terms of the components of q = (q , q , , q ) which is the four momentum of the exchanged virtual photon in the laboratory frame. when defining d = q + ( q + q q − q ) (b. ) and d = q q + q (q − q ) , (b. ) the lorentz parameter is given by β = d q + q /(q − q ) , (b. ) the rotation about the y-axis in the hera frame is given by sin α = − q d , cos α = q + q /(q − q ) d (b. ) and the final rotation about the y axis in the breit frame is given by sin α′ = qq d , cos α′ = − q (q − q ) d . (b. ) details can be found in [ ]. the overall transformation matrix takes the simple form l(l → b) = ⎛ ⎜⎜⎜⎝ q q + q q −q − q q − q q − q q −q − q q −q q q −q q q − q q − q q ⎞ ⎟⎟⎟⎠ . (b. ) appendix c cross section tables measurement experimental errors correction factors ημ-range dσ/dημ stat. sys. fb �rec δrad [pb] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . - - . . . . . . ± . . - . . . . . . ± . . - . . . . . . ± . . + . . . . . . ± . . + p μ t -range dσ/dp μ t stat. sys. fb �rec δrad [gev] [pb/gev] [pb/gev] [pb/gev] [%] [%] [%] . . . . . . ± . . + . . . . . . ± . . - . . . . . . ± . . + . . . . . . ± . . - . . . . . . ± . . + . . . . . . ± . . - p jet t -range dσ/dp jet t stat. sys. fb �rec δrad [gev] [pb/gev] [pb/gev] [pb/gev] [%] [%] [%] . . . . . . ± . . + . . . . . . ± . . - . . . . . . ± . . + q -range dσ/dq stat. sys. fb �rec δrad [gev ] [ pb/gev ] [ pb/gev ] [ pb/gev ] [%] [%] [%] . . . . . . ± . . - . . . . . . ± . . - . . . . . . ± . . . . . . . . ± . . + log x-range dσ/d log x stat. sys. fb �rec δrad [pb] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . - - . - . . . . . ± . . - . - . . . . . ± . . + - . - . . . . . ± . . + - . - . . . . . ± . . - - . - . . . . . ± . . + - . - . . . . . ± . . - table c. : differential cross sections for the process ep → ebb̄x → ejμx′ in the kinematic range . < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors p jet t -range dσ/(dp jet t dη μ) stat. sys. fb �rec δrad [gev] [pb/gev] [pb/gev] [pb/gev] [%] [%] [%] . . . . . . ± . . + . . . . . . ± . . - . . . . . . ± . . - table c. : differential cross sections as a function of the transverse momentum of the jet in the kinematic range . < q < gev , . < y < . , pμt > gev, − . < ηµ < , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors p jet t -range dσ/(dp jet t dη μ) stat. sys. fb �rec δrad [gev] [pb/gev] [pb/gev] [pb/gev] [%] [%] [%] . . . . . . ± . . . . . . . . ± . . - . . . . . . ± . . - table c. : differential cross sections as a function of the transverse momentum of the jet in the kinematic range . < q < gev , . < y < . , pμt > gev, < ηµ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors p jet t -range dσ/(dp jet t dη μ) stat. sys. fb �rec δrad [gev] [pb/gev] [pb/gev] [pb/gev] [%] [%] [%] . . . . . . ± . . + . . . . . . ± . . + . . . . . . ± . . - table c. : differential cross sections as a function of the transverse momentum of the jet in the kinematic range . < q < gev , . < y < . , pμt > gev, . < ηµ < , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors log x-range dσ/(d log xdq ) stat. sys. fb �rec δrad [pb] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . - - . - . . . . . ± . . - - . - . . . . . ± . . - table c. : differential cross sections as a function of the scaling variable x in the kinematic range . < q < . gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors log x-range dσ/(d log xdq ) stat. sys. fb �rec δrad [pb/gev ] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . - - . - . . . . . ± . . - . - . . . . . ± . . - table c. : differential cross sections as a function of the scaling variable x in the kinematic range . < q < . gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors log x-range dσ/(d log xdq ) stat. sys. fb �rec δrad [pb/gev ] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . - . - . . . . . ± . . - - . - . . . . . ± . . - table c. : differential cross sections as a function of the scaling variable x in the kinematic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors log x-range dσ/(d log xdq ) stat. sys. fb �rec δrad [pb] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . - - . - . . . . . ± . . - - . - . . . . . ± . . - table c. : differential cross sections as a function of the scaling variable x in the kinematic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. measurement experimental errors correction factors log x-range dσ/(d log xdq ) stat. sys. fb �rec δrad [pb] [pb] [pb] [%] [%] [%] - . - . . . . . ± . . + - . - . . . . . ± . . - - . - . . . . . ± . . - table c. : differential cross sections as a function of the scaling variable x in the kinematic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . also given are correction factors as obtained from the monte carlo simulation and the beauty fractions of the event sample. nlo prediction theor. uncertainty correction to hadron level ημ-range dσ/dημ sys. ch − [pb] [pb] [%] - . - . . + . − . - . - . . . + . − . - . . . . + . − . - . . . . + . − . - . . . . + . − . - . p μ t -range dσ/dp μ t sys. ch − [gev] [pb/gev] [pb/gev] [%] . . . + . − . - . . . . + . − . - . . . . + . − . - . . . . + . − . - . . . . + . − . - . . . . + . − . - . p jet t -range dσ/dp jet t sys. ch − [gev] [pb/gev] [pb/gev] [%] . . . + . − . - . . . . + . − . - . . . . + . − . + . table c. : predictions from next-to-leading order qcd calculations in the kine- matic range . < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level q -range dσ/dq sys. ch − [gev ] [ pb/gev ] [ pb/gev ] [%] . . . + . − . - . . . . + . − . - . . . . + . − . - . . . . + . − . - . log x-range dσ/d log x sys. ch − [pb] [pb] [%] - . - . . + . − . - . - . - . . + . − . - . - . - . . + . − . - . - . - . . + . − . - . - . - . . + . − . - . - . - . . + . − . - . - . - . . + . − . - . table c. : predictions from next-to-leading order qcd calculations in the kine- matic range . < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level p jet t -range dσ/(dp jet t dη μ) sys. ch − [gev] [pb/gev] [pb/gev] [%] . . . + . − . - . . . + . − . - . . . + . − . + table c. : predictions from next-to-leading order qcd calculations in the kinematic range . < q < gev , . < y < . , pμt > gev, − . < ηµ < , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level p jet t -range dσ/(dp jet t dη μ) sys. ch − [gev] [pb/gev] [pb/gev] [%] . . . + . − . - . . . + . − . - . . . + . − . + table c. : predictions from next-to-leading order qcd calculations in the kinematic range . < q < gev , . < y < . , pμt > gev, < ηµ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level p jet t -range dσ/(dp jet t dη μ) sys. ch − [gev] [pb/gev] [pb/gev] [%] . . . + . − . - . . . + . − . - . . . + . − . + table c. : predictions from next-to-leading order qcd calculations in the kinematic range . < q < gev , . < y < . , pμt > gev, . < ηµ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level log x-range dσ/d log x sys. ch − [pb] [pb] [%] - . - . . + . − . - - . - . . + . − . - - . - . . + . − . - table c. : predictions from next-to-leading order qcd calculations in the kine- matic range . < q < . gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level log x-range dσ/d log x sys. ch − [pb] [pb] [%] - . - . . + . − . - - . - . . + . − . - - . - . . + . − . - table c. : predictions from next-to-leading order qcd calculations in the kine- matic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level log x-range dσ/d log x sys. ch − [pb] [pb] [%] - . - . . + . − . - - . - . . + . − . - - . - . . + . − . - table c. : predictions from next-to-leading order qcd calculations in the kine- matic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level log x-range dσ/d log x sys. ch − [pb] [pb] [%] - . - . . + . − . - - . - . . + . − . - - . - . . + . − . - table c. : predictions from next-to-leading order qcd calculations in the kine- matic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . nlo prediction theor. uncertainty correction to hadron level log x-range dσ/d log x sys. ch − [pb] [pb] [%] - . - . . + . − . - - . - . . + . − . - - . - . . + . − . - table c. : predictions from next-to-leading order qcd calculations in the kine- matic range < q < gev , . < y < . , pμt > gev, − . < ημ < . , pjett > gev and |ηjet| ≤ . . appendix d level z-vertex trigger d. overview the successfull hera ii physics program is based on the four to five times higher instantaneous luminosity that was delivered to the experiments. the upgrade of the storage ring required an upgrade of the detectors. for the h detector it was decided to keep the reliable data acquisition electronics and to increase the sensitivity of the experiment to interesting events instead. therefore new trigger electronics and algorithms were developed, based on signals from different subdetectors. the jet trigger was designed to recognise local energy depositions in the liquid argon calorimeter. the dcrphi trigger [ ] was replaced by the fast track trigger (ftt) [ , ], both processing drift chamber information. one important part of the trigger upgrade was the replacement of the cip detector by an improved detector consisting of five instead of three layers and new trigger electronics [ ]. only by rejecting beam induced background, like beam gas and beam wall events (see figure d. ), at an early stage at level , an efficient use of the trigger bandwith for all other physics triggers was possible. nevertheless, at the beginning of the hera ii data taking the cip was still in the commissioning phase figure d. : event display of a beam gas induced background event. cjc cjc figure d. : a radial view of the ftt, the cjc wires used by the ftt are indicated as dashed lines. only the three inner ftt layers of cjc are used for the z vertex trigger. and only three out of five layers were operational. this was accompanied by very high beam induced backgrounds. it was highly desirable to have a backup solution for the cip trigger, therefore studies were conducted that demonstrated the feasibility of a z vertex trigger based on drift chamber signals at level by extending the ftt functionality [ ]. for this only a minimum of additional hardware was necessary. the corresponding interfaces for this upgrade were introduced from the beginning in the design of the ftt data flow and the algorithms were finally implemented within the work of this thesis. in the following a brief overview of the ftt is given followed by a discussion of the z vertex trigger algorithm. d. . fast track trigger in order to cope with the higher rates after the hera ii upgrade and to increase the selectivity, the fast track trigger was built to replace the dcrphi trigger. of special interest is a high selectivity in the photoproduction region where the rate of signal and background events is high and no suppression based on triggering on the scattered electron is possible. therefore a purely track based trigger is necessary, using information from the central drift chambers. the drift chamber signals allow for a standalone track reconstruction, the achieved resolution of % pt/ gev is com- parable to the offline resolution. the ftt allows for a low momentum threshold of mev, compared to a threshold of mev for the dcrphi trigger. this is of special interest for the study of soft physics, e.g. production of mesons at the production threshold (very low transverse momenta). the large dynamic range of track momenta and the pattern recognition on a short timescale within ns are a major challenge. in addition the algorithms had to be designed to deal with the large drift times of - bunchcrossings within the drift chambers. cjc cell in-cell wires neighbour upper left lower right neighbour la ye r la ye r la ye r figure d. : geometry of the cjc with wires marked used for the ftt (from [ ]). each group consists of three wires, the upper left and lower right neighbour wire are included in the processing of each group. the ftt uses only a fraction of from wires of the drift chambers. a radial slice of the drift chambers is shown in figure d. . as indicated, the ftt wires are arranged in four trigger layers, three for the inner chamber and one for the outer chamber. the inner and outer layers consist of and trigger cells, respectively. each trigger group is made of three ftt wires. the cell geometry for the inner layers is depicted in figure d. . the local pattern matching is performed within these trigger cells. the ftt provides trigger information on all three trigger levels, where the first two levels are solely based on drift chamber signals. at level track segments are linked in the transverse plane, yielding coarse track parameters. finally the trigger decision is determined, in total a set of trigger elements (tes) is forwarded to the central trigger logic. these trigger elements are based on the number of tracks above a certain momentum threshold, the total charge of the tracks and the arrangement of tracks in the r − φ plane. all these calculations have to be performed within the level latency of . μs ( bunch crossings). details can be found in [ ]. the z vertex trigger, that is described in this thesis, is part of level . at level track segments are linked based on refined segment information. a - dimensional primary vertex constrained fit is performed. this consists of a circle fit in the transverse plane, which is able to fit four track segments within . μs. in the longitudinal plane a straight line fit is performed, combining up to hits and the z vertex position. this fit can be performed within . μs. the level -linker algorithm is described in detail in [ ], the -dimensional fit in [ ]. the vertex position in z that is used for the fit in the longitudinal plane is determined by the ftt on an event-by-event basis [ ]. in addition it was possible to perform an invariant mass reconstruction already on level using the parameters determined by the track fits [ ]. finally internal ftt trigger elements [ ] are generated making use of the higher precision and resolution at level . these trigger elements are combined to physics triggers that are sent to the central trigger logic. the internal trigger elements are based on track multiplicities above a certain threshold, track topologies in the transverse plane and the total charge in the event. level does not only verify and refine level information but also delivers information based on the z vertex and additional kinematic quantities like the et and pt, which is the scalar and vectorial sum of charged particle momenta, vp and vap, which is the amount of momentum parallel and antiparallel to the direction of missing mo- mentum, and the invariant mass of two track combinations. the total time available on level is μs. at level a partial event reconstruction is performed by determining invariant masses based on the high precision tracks delivered from level . for this purpose physics algorithms like the selection of d∗ candidates run on commercial proces- sors [ , , ]. at level it is possible to combine track information with in- formation from other detectors, like the muon system [ ] and the liquid argon calorimeter. the latter allows the search for electronic decays of beauty mesons at low momenta [ , ]. the total time available for level is μs. r z figure d. : mutually exclusive valid patterns for the segment finding (from [ ]). each pattern defines a local search neighbourhood, consisting of five hit positions for the outer and inner wire and three hit positions for the middle wire. for the positions marked in black a hit is required, for positions marked in white no hit is allowed. the grey patterns denote “don’t care” positions. d. . z vertex trigger the z vertex trigger algorithm consists of the following steps: • for each ftt-wire a hit finding algorithm is applied, followed by a calculation of the z-coordinate of the hit. the hit finding is common for the z vertex algorithm and the r-φ part of the ftt. the result of the z measurement is given in two representations, with a resolution of bins for the level system and a resolution of bins ( cm per bin) for the level z vertex part due to bandwith limitations . the hit finding and the z measurement are explained in more detail in section d. . . • for each of the trigger cells of the inner three ftt layers a search for track segments is performed. the pattern matching algorithm is based on hitpatterns along the z-coordinate, where five bins of each inner and outer wire and three bins of the middle wire build a local search neighbourhood. the valid patterns are summarized in figure d. . all patterns are mutually exclusive and also patterns consisting of only two hits are valid to account for the limited hit finding efficiency. the result of this part of the algorithm are z-segments for each of the trigger cells. • in the linking step all combinations of two segments belonging to different layers are extrapolated to the beamline, and the intercept is entered into a his- togram. this extrapolation is done separately for different φ-sectors (see technically an internal representation of bit is used, which is converted to a and bit representation. the hit information of the outer wires is combined with the information from neighbour wires. �� trigger layer trigger layer ° trigger layer figure d. : illustration of a φ sector. the vertex histogram is calculated for each sector seperately. within the overlap region cells contribute to both sectors. figure d. ). the final vertex histogram is the sum of these individual his- tograms and consists of bins with a binwidth of cm, covering the range from − m to m. this has to be compared to a much coarser binning of about cm for the cip, where the number of bins is only . the extrapolation method is illustrated in figure d. . • finally this vertex-histogram is evaluated by counting the histogram entries and performing a peak search. the trigger decision is based on the peak position and the number of entries in the signal region of the histogram compared to the total histogram contents. several aspects make the implementation of the z vertex algorithm a challenging task: • the algorithm has to account for the large drift times up to - bunch cross- ings. a hit might constitute a valid segment combined with a hit detected later due to a larger drift time. therefore hits have to be held in pipelines of sufficient length. a large fraction of the available time at level is spent for waiting for the latest hits. this latency is about five times larger than the hit finding itself. • due to the limited time available at level one, the z vertex algorithm has to run in parallel to the r-φ-part. since large parts of the algorithms run in parallel on the same hardware, a large fraction of the resources for the individual fpgas has to be shared. this implies complications concerning the timing constraints of the final design at register transfer level. in addition the bandwidth for signal reconstructed tracks tracks hits combinatorial background r axis z axis trigger layer trigger layer trigger layer signal region intersect histogram figure d. : sketch of the z-linking process (from [ ]). all combinations of two segments are extrapolated to the beamline, leading to entries in the vertex histogram. the entries are weighted and smeared according to the different precision depending on the layer combination. transmission between the different hardware components is limited. • in comparision to the z vertex algorithm at level , not only r-φ linked segments are considered for the extrapolation, but all segments for the inner three layers. therefore the algorithm suffers from a much larger number of z-segments and z- segment combinations, resulting in a smaller signal to noise ratio. this problem is enhanced by the fact that the outer ftt layer is not used for the algorithm due to hardware limitations. combining segments from the inner and the outer layer (cjc ), which is possible at level , allows for a large lever arm and a much higher precision for the peak measurement. d. data flow and hardware the ftt level trigger system is distributed over a large number of hardware boards, most of them are used for level functionality as well. an illustration of the level system is given in figure d. . the processing of the drift chamber data starts at the front end modules (fem). each fem processes the data coming from trigger cells ( wires times two wire ends). in total the system consists of fems, each of the three inner trigger layers is connected to fems. the outer layer is not used by the level z vertex trigger. after digitization the hit finding and z measurement is performed, followed by the segment finding in the r-φ and r − z plane, which is done in parallel. fem fem fem fem fem fem ii pb io pbio pb ii pb l linker controller lvds mhz mhz lvds mhz lvttl mhz mhz merger card pb linker linker l z pb figure d. : overview of the ftt l trigger system, showing the data flow from the fems to the various linker cards via the merger cards. in addition, the segment finding at level with a higher resolution is performed on the fems. the fems transmit the data to the merger card at a rate of mhz via lvds channel links. therefore the merger cards are equipped with four piggy back cards that receive the data. two different types of piggy back cards are used, the ii-type has two input channels, the io-card one input and one output channel. merger and piggy back cards are operated at a frequency of mhz. the merger collects the r-φ and z data from fems and forwards this information to the linker and z linker, respectively (see figure d. ). the z data is organized in sectors ( or groups each) and sent out in sequence. one of the io-piggy back cards sends the merged r-φ segments to the linker card via one lvds channel link, the other io-piggy back card sends r − z segments to the z linker card via a second lvds channel link. in addition, r-φ segments for level are sent, therefore merger and piggy back cards switch between level mode and level mode. in level mode, the z linker piggy back card, that is receiving the data from the merger, is forwards the data to the l linker card. the merger card and the different linker cards are multipurpose processing boards (mpbs). both, the mpbs and the fem hardware and the used key technologies are presented in more detail in the following subsections. d. . front end modules and multipurpose processing boards for the ftt level and level hardware two types of boards are used: front end modules (fems, figure d. ), built by rutherford appleton laboratory, and several multipurpose processing boards (mbps, figure d. ), built by supercomputing sys- tems (scs). each front end module is equipped with dual bit analogue to digital converters (adcs) of type ad - [ ] for sampling the analogue signal low voltage differential signaling [ ] of trigger groups at a rate of mhz. the further digital processing is performed on fpgas of type altera apex k e [ ]. five of them, the so-called front fpgas, perform the hit finding, z measurement and segment finding in the r-φ plane. to include information from neighbour wires, these fpgas are cross-linked with the neighbour fpgas. the front fpgas are clocked with a frequency of mhz. the sixth fpga of this type (so called back fpga) synchronizes and collects the track segments from the front fpgas and forwards them to the merger system. the five front fpgas and the back fpga are connected via a bit bus. in level mode a validation of the track segments is performed, using higher granularity masks stored in ram. (for the level two verification and lookup the board is equipped with a mb zero bus turnaround (zbt) memory.) the segment finding in the r-z plane at level is an extension of the trigger functionality using the remaining hardware resources. in addition this board is equipped with a fpga of type altera flex which provides a vme interface for configuration and readout. many components of the ftt, including the merger system and different linkers, are implemented on multiporpose processing boards using different firmware imple- mentations. each mpb hosts up to four piggy back cards providing two gbit/s channel links each, controlled by an altera apex k e fpga. the correspond- ing buses are collected on the main board by the data controler fpga, which hosts the linker algorithms for the linker cards and the merger algorithm for the merger card. the fpgas are of type altera apex kc e for the linker boards and altera apex k e for the merger boards. a fpga of type altera flex epf k a is used to control the vme interface. at level fitter boards are used for track fits, which are in addition equipped with four floating point dsps and a corresponding dsp controller fpga. d. . key technologies the implementation of fast and parallel algorithms and the successful commissioning of the ftt was only possible by the use of fast and flexible programmable hardware on level and level . as the ftt is based on pattern matching algorithms a dedicated memory technology is used. both key technologies are briefly presented in the following. field programmable gate arrays (fpgas) fpgas are programmable integrated circuits (ics). they are used for complex applications, where flexibility and reprogrammable redesign are important. this is especially important during the commissioning phase. an overview of the apex k device is shown in figure d. . this device incorpo- rates lut-based logic , product-term-based logic and memory. these components are organized in groups consisting of logic array blocks (labs) and embedded sys- vesa module europe lut stands for look-up-table, which is a function generator that implements any function of four variables. figure d. : photo of a front end module (from [ ]). : connector for analogue signal cables : adcs . front fpgas : back fpgas : zbt ram : vme interface fpga : vme connector j : custom backplane connector : jtag connectors. figure d. : picture of a multipurpose processing board (from [ ]). : dsps : dsp controller fpga : data controller fpga : piggy back connectors : vme interface fpga : vme connector j : custom backplane connector : logic analyser connector for data controller fpga : logic analyser connector for dsp controller fpga : jtag connectors : status leds. for the z linker a simplified version is used without dsps and dsp controller fpga. not visible are two more piggy back connectors, a dual ported ram and dpram controller fpga on the back side. figure d. : apex k device block diagramm (from [ ]). shown are the logic array blocks, consisting of lut-based logic, product-term-based logic, and memory. these blocks are connected via fast interconnections (fasttrack interconnect). tem blocks (esbs) and connected via fast interconnections. the smallest units of this architecture are logic elements (les). each le contains a four-input lut, a programmable register and carry and cascade chains . product-term logic is im- plemented using esbs. in this mode, each esb contains macrocells consisting of two product terms and a programmable register each. the esb can implement various types of memory blocks, including dual-port ram, rom, fifo, and cam blocks. the latter is discussed in the following subsection in more detail due to the importance for the used algorithms. content adressable memories (cams) content adressable memories are associative memories based on ram technology. instead of receiving the address and supplying the data as in conventional ram memory, a data word is compared to a list of pre-loaded data words, and the address of the matching data word(s) is signaled. the search through all memory locations is done in parallel. cams are used for implementing high-speed search applications, e.g. pattern matching algorithms. the used apex ke device contains on-chip cam which is built into the esb blocks [ ]. the core task of the z vertex trigger and the ftt in general is a fast pattern matching of drift chamber hits. all valid patterns shown in figure d. are used to pre-load the cams during configuration. the cam units allow for a third matching state, the “don’t care” state (ternary cam). as all patterns are disjoint, the single match mode can be used. for this mode only one clock cycle is needed to read the stored data. carry chain logic is used to implement counters, adders and comparators. cascade chain logic is used to implement functions with a very wide fan-in. d. implementation of the z vertex trigger in this chapter the implementation of the z vertex trigger is discussed in detail. since this is based on the programming of fpgas using the hardware description language vhdl, this chapter begins with a brief discussion of vhdl and the development process. after this the different steps of the algorithm are presented. d. . vhdl the algorithm is implemented using the hardware description language vhdl . the use of this high level language allows a high level of abstraction for the system design, including top-down and bottom-up design approaches and reusable components. a common modelling for the simulation and the synthesis of the design can be used. digital hardware is described in vhdl using concurrent assignments, concurrent processes, and local signals for the communication between them. for processes the use of sequential statements is allowed. this way it is possible to implement not only combinatorical logic but sequential logic using storage components like flip flops. more details can be found e.g. in [ ]. for the implementation the quartus ii design software [ ] is used. this is an integrated development environment for all design steps, including the compilation, simulation, synthesis, placement and routing. during the synthesis step a netlist is produced. the last step, the mapping of the netlist to the hardware and connecting the components is a very time consuming step. for complex designs this step has to be repeated several times to fulfill the timing requirements. d. . hit finding and z measurement both hit finding and the z measurement are performed on the front fpgas of the front end modules. therefore the digitized signal of channels (both ends of wires, wires of the corresponding cell plus two neighbour wires) is fed into the front fpga at a rate of mhz. this results in a total input rate of gbit/s. the hitfinding and the z measurement, performed by the qt algorithm and a charge division algorithm, are described in the following. qt algorithm a difference of samples (dos) method is used to measure the hit timing. therefore for each time slice n the difference of the digitized wire value to the previous time slice n − is calculated, δn = sn − sn− , (d. ) where sn is the sum of both wire ends. a hit is found at a time slice n if the following conditions are fulfilled: • the difference δn is above a certain threshold, which implies a minimum slope for the rising edge of the hit. very high speed integrated circuit hardware description language charge left charge right sum dos threshold time a d c c o u n ts figure d. : illustration of the difference of samples method (from [ ]). • the difference δn is larger than the difference for the next time slice δn+ . this dos technique is illustrated in figure d. . by applying these conditions a hit finding with high efficiency and purity, high precision of the hit timing measurement and high accuracy of the charge measurement is possible. this step of the algorithm takes only three mhz clock cycles. with the availability of the hit information, the segment finding in r-φ can proceed. charge division to determine the z value, a charge integration is performed for both wire ends. the principle of the charge integration is illustrated in figure d. . the integration is performed for six clock cycles and starts as soon as the difference of samples is above the threshold. a noise substraction is performed, therefore a pedestal integration of six clock cycles is performed eight clock cycles before the hit (in phase with the hera clock to reduce the influence of correlated noise). for a time period of clock cycles after the hit integration, no pedestal integration is allowed. the values ql and qr for the measured charges are then entered into the simple formula z = lef f ql − qr ql + qr , (d. ) where lef f is the effective wire length, which is not only determined by the physical wire length but also by electronics at the wire ends (see figure d. ). if the values for the charges at both wire ends are equal, the formula yields a value z = for the hit position, which is the center of the wire. time a d c c o u n ts ( o n e w ir e e n d ) h it in te g ra tio n h it in te g ra tio n h it in te g ra tio n p e d e st a l i n te g ra tio n p e d e st a l v e to figure d. : illustration of the charge integration method (from [ ]). shown are the interval for the signal integration, the interval for the background integration (pedestal) and the veto region, where no pedestal integration is allowed. cm ~ Ω . nf . nf Ω Ω central jet chamber wire preamplifier figure d. : illustration of cjc wires (from [ ]). for the qt algorithm an effective wire length is used, which accounts for the impedance due to electronics at both wire ends. data line l /monitor mode mhz clk inverted κ enable z enable bc half monitor enable .. monitor data .. z( .. ) .. z( .. )/κ( .. ) table d. : front fpga to back fpga protocol. only the protocol for the level and monitor mode is shown. d. . segment finding the segment finding in r − z is performed on the back fpga. the functional design of the vhdl implementation is shown in figure d. . the data is processed by three different units: synchronizer the first step is the synchronization of five mhz bit data streams (one data stream for each trigger cell) to the mhz clock of the back fpga. for the synchronization the inverted mhz clock is transmitted via the data stream. as a result only of the clock cycles per bunch crossing contain valid data. three different protocols are used: level mode, level mode and read-out control mode. in level mode, the z data is sent two times per bunch crossing. for each half bunch crossing times bit encoded z data is transmitted, which takes two clock cycles. for these clock cycles the z-enable bit of the data stream is set, the bunch crossing half is indicated by another bit. the front fpga to back fpga protocol for level one is shown in table d. . pipeline units to account for the large drift times of the detector, the hit information is fed into five pipeline units, one for each cell, and stored for bunch crossings. therefore it is possible to form hit patterns consisting of hits detected at different bunch crossings but belonging to the same event. each pipeline unit contains five counter units, three for the cell wires and two for the left and right neighbour wire. each counter unit uses counters to model one pipeline per z position. twice a bunch crossing it is checked whether a hit was detected for each z position. in this case the counter is set to and the bit corresponding to this z position is enabled. the counters are decremented per bunch crossing, and the corresponding bit is disabled if the counter is at zero. half bunch crossings e n tr ie s early late e n tr ie s half bunch crossings figure d. : drift spectrum for z hits for the innermost layer and the outermost layer. this data was read out from the back fpga. for each cell bit ( z positions per wire) are written to a cyclic memory which is used to feed the data to the cam unit. in addition, the hit information is written to a dedicated cyclic memory twice per bunch crossing for timing studies. this memory has a depth of bunch crossings and can be read out via vme. the number of z hits with respect to the half bunch crossing is shown in figure d. for the innermost layer and the outermost layer, ordered from earlier to later bunch crossings. the first hits are written to the memory bunch crossings before the pipelines are stopped by the central trigger decision. the rising edges for all trigger layers show that the pipelines are stopped at the same time with respect to the central trigger signal for each event. the width of this distribution denotes the maximum drift time, which is about bunch crossings for the innermost layer and about bunch crossings for the outermost layer. the latest hits are available only about bunch crossings before the pipelines stop. as all subsequent processing and transmission steps exceed this time constraint, only the fraction of hits that are available early enough is processed and included to the trigger decision. to maximize this fraction, all steps of the algorithm have to be optimized with regard to processing time and parallelism. cam unit the cam unit performs the search for track segments in a local search neighbour- hood. bit of z-information from three wires is presented to cams (one for each z position, omitting the edge positions) in parallel and compared to predefined patterns. this principle and the z-patterns are illustrated in figure d. and d. . the data from five groups has to be processed, but due to limited resources only one cam unit is available. therefore the data from each group is presented to the cam unit in sequence using a state machine. the result of this pattern matching is represented by five bit vectors, where each component represents a z-bin. these vectors become available in sequence for each group. to reduce the amount of data to be transmitted and processed, a reduction to three bit vectors is necessary by merging these vectors. three groups of bit z data are defined, which belong to fem pb card pb type group layer layer layer m ko - - - ( ) - ( ) - ( ) - ∗ m ii a ( ) - ( ) - ( ) - - - - m ii a - ( ) - ( ) - ( ) - - m ii b - - - ( ) - ( ) - ( ) - m ii b ( ) - ( ) - ( ) - - - - m zo - ( ) - ( ) - ( ) - - table d. : cjc merger input. only the z data is shown, in addition κ informa- tion is sent. the merger receives three groups of z data for each of the five fems for one layer. the data denoted with * is not transmitted due to bandwidth limitations. one sector (see figure d. ). for each group a bitwise or of three or four vectors is performed, depending on the fem type and layer. this is summarized in table d. . finally the z data is sent out to the merger cards in three groups of bit. the sequence of data sent to the merger card is summarized in table d. . three cycles are needed for the z data, two cycles for the r-φ data. d. . merging the amount of data is further reduced by merging the z segments on three merger boards, one for each layer. sectors are defined, with overlap regions between them (figure d. ). as the implementation of the merger algorithms is not part of this thesis, only a brief overview of the merger functionality is given. the merging scheme is complicated because r-φ data and z data are processed on the same merger. a detailed description including the detailed merging scheme and r-φ functionality can be found in [ ]. the fem-merger channel links are operated at mhz. the protocol is given in table d. . five bytes are available for the unencoded z position per group, dedicated header bits are used to denote the group number. in addition r-φ information is sent via these channel links. control words are used for switching between the level and level mode. for each bunch crossing the begintriggerdata control word is step word hclk fem control word → lower bytes rφ segments higher bytes rφ segments empty word empty word bits z segments group → bits z segments group bits z segments group empty word empty word table d. : sequence of sending data at mhz ( cycles per bunchcrossing) from the fem to the merger cards. synchronizer pipeline unit counter unit counter unit counter unit counter unit counter unit cam unit cam cam cam array state machine pipeline unit counter unit counter unit counter unit counter unit counter unit pipeline unit counter unit counter unit counter unit counter unit counter unit pipeline unit counter unit counter unit counter unit counter unit counter unit pipeline unit counter unit counter unit counter unit counter unit counter unit group group group group group hits patterns wire wire wire wire wire cams figure d. : functional design of the segment finding unit of the back fpga. hits from each trigger group are fed to the pipeline units. each pipeline unit consists of counter units, one for each ftt wire. the cam unit consists of cam memories, one for each z position. wire , wire wire , segment figure d. : principle of the pattern matching performed on the back fpga. for each z position a local pattern matching is performed, resulting in a segment array. data type byte byte byte byte byte byte invalid/no data x x x load load load load load track segments cell#( .. )load( .. ) load load load load load l mode header cell cell cell cell cell empty word p ignored ignored ignored ignored ignored rφ segments (low) p lower byte lower byte lower byte lower byte lower byte rφ segments (high) p higher byte higher byte higher byte higher byte higher byte z segment group p unencoded z position z segment group p unencoded z position z segment group p unencoded z position control words x x p begintriggerdata p fem# x #hclk #hclk #hclk switchtol mode p fem# x #l keep #l keep #l keep nomoresegments p fem# x x x #sent segments switchtol mode p fem# x #l keep #l keep #l keep table d. : fem-merger protocol. p stands for parity bit. the control words contain counter information for monitoring purposes. sent along with the actual hera clock counter. for each of the three trigger layers used by the z-trigger, one merger receives z data data via four piggy back cards. one of these cards forwards the data to the z linker. clock cycles after receiving the begintriggerdata control word, the last z sector is sent to the z linker card. the channel link to the z linker is operated at mhz, the protocol is summarized in table d. . the sequence of data and control words from the merger to the z linker card is summarized in table d. . the begintriggerdata control word is sent only once at the beginning of the level mode. d. . linking and trigger decision the linking of the segments is the essential part of the algorithm. this is performed on a dedicated mpb-board, the z linker, operated at mhz. the z data is received by the z linker via three lvds channel links, one for each layer. the linking step is followed by the evaluation of the resulting vertex histogram and the generation of trigger elements which are sent to the central trigger. the different modules of the implementation are discussed in the following. data type byte byte byte byte byte byte invalid/no data (l mode) track segments cell#( .. )load( .. ) load load load load load l mode header byte byte byte byte byte z segment sector+ s unencoded z position control words x x p begintriggerdata p fem# x #hclk #hclk #hclk switchtol mode p fem# x #l keep #l keep #l keep nomoresegments p fem# x x x x switchtol mode p fem# x #l keep #l keep #l keep table d. : merger-z-trigger protocol. p stands for parity bit. the control words contain counter information for debugging purposes. for the sector which is sent first in a sequence (sector ) the startbit s is set high. in level mode track segments are sent. step word hclk merger begintriggerdata → sector z segment sector z segment sector z segment sector z segment sector z segment → sector z segment sector z segment sector z segment sector z segment sector z segment → ... ... ... ... switchtol mode ... ... ... ... ... l track segments ... ... ... ... nomoresegments ... ... ... ... ... switchtol mode ... table d. : sequence of data sent from the merger to the z linker. signal region: bin - backward region: bin - forward region: bin - z figure d. : illustration of the vertex histogram, divided into backward, signal and forward region. parameter value length cjc cm centre cjc cm radius inner layer r . cm radius middle layer r . cm radius outer layer r . cm #histogram bins histogram length cm histogram centre cm table d. : cjc and vertex histogram parameters used for the extrapolation of z segments. receiver unit this unit synchronizes the data from three trigger layers. the incoming data is written to input buffers, implemented as cyclic memories. the synchronization step is performed by a final state machine that writes the data to three z buses, one for each trigger layer. the data of one sector is written per clock cycle to each bus. in total ten clock cycles are needed for all ten sectors. histogram unit the histogram unit performs the linking step of the algorithm by extrapolating seg- ment pairs linearly to the beam line. it consists of three linking units, corresponding to the three possible combinations of two layers. each of these linking units fills a bin z vertex histogram with a binwidth of cm. the linear extrapolation of segment pairs to the beamline using the geometric cjc parameters given in table d. is performed offline. for each histogram bin all segment combinations, that can be extrapolated to that bin (links) are calculated offline, and the corresponding vhdl code is generated. the algorithm is pipelined, the linking is performed for each of the ten sectors in sequence sharing the same hardware. each link gives an entry for the corresponding bin. the vertex histogram is calculated by summing up the number of links for each bin. this cannot be done in one clock cycle due to timing constraints. for each bin an adder with a large fan-in would be required. instead, the addition is done in several steps within five clock cycles using a chain of adders. the sum unit is used to add the individual histograms for each layer combination. the algorithm is pipelined, therefore one tenth of the histogram is processed for each clock cycle. the vertex histograms for all ten sectors become available in sequence and are summed up to the final vertex histogram. after ten clock cycles the data from the next bunch crossing is processed. to take into account the higher resolution for the combina- tion layer - layer due to the longer lever arm, a weighting scheme is applied: the radii of the different cjc layers used for the algorithm deviate from the physical parameters and are chosen in a way to avoid binning artefacts (moiré effects). trigger element method signal region te top peak - cm - cm te top peak - cm - cm te top peak - cm - cm te significance - cm - cm table d. : trigger elements provided by the z vertex trigger. they correspond to two different methods for evaluating the vertex histogram and different definitions of the signal region. histogram entries from this combination get a weight of three, whereas entries from the other two layer combinations are smeared to the left and right neighbour bin. the peakfinder unit analyzes the vertex histogram. a peak search is performed and entries for the central, forward and backward region are counted. an asym- metric signal window is defined from bin to as illustrated in figure d. . due to secondary tracks showering in the forward region, the signal window had to be extended to the forward region. d. . trigger element generator unit this unit processes the results from the histogram unit given by the number of entries for the three different histogram regions and a bit array containing the peak information. two different methods are used: for the significance method the number of entries for the signal and background regions are compared. the corresponding trigger element is enabled if the condition nsignal > (nf orward + nbackward) (d. ) is fulfilled. a similar method was used for the level z vertex trigger and the cip trigger. for the top peak method the peak array is evaluated. the corresponding trigger condition is fulfilled if the position of the top peak is within the signal window. three different asymmetric signal windows are defined. in total four trigger elements are defined, they are summarized in table d. . all four trigger elements are sent to the central trigger. to fulfill the timing requirements with respect to the central trigger and to synchronize the four trigger elements, additional individual delays are added. d. . timing the processing and transmission times needed for the individual steps of the algo- rithm are summarized in table d. . the accumulated time is estimated to ns. as the maximal level latency is ns and the maximum drift time is ns, this results in an implicit cut into the hit distribution for the outermost layer (see figure d. ). the latest hits (about three bunch crossings) for this layer are therefore not included in the processing of the vertex histogram. delay clock cycles time (ns) accumulated (ns) analogue cable delay - fem: digitization - fem: charge integration (ffpga) fem: charge division (ffpga) fem: data preparation (ffpga) fem: segment finding (bfpga) channel link: fem-merger - merger: merging channel link: merger-z linker - z linker: receiving, synchronizing z linker: linking z linker: pipelining z linker: summing histograms z linker: evaluating histogram z linker: te driver, delay transmission of trigger elements to ctl table d. : summary of time consumption of the algorithm for the different pro- cessing and transmission steps. d. results d. . cosmic runs in the course of the commissioning phase the first test were performed using data from cosmic runs. the cosmic muon events recorded during this runs provide ideal back to back two track events. the functionality of the trigger is documented in figure d. where the correlation between z vertex position as determined by the h event reconstruction and the position of the top peak is shown. figure d. shows an overlay of many vertex histograms for ideal single track events from cosmic runs. as the vertex position of each event is distributed uniformly, each single histogram is shifted to the central bin. the overlay histogram has a small width and peaks at the central bin. this demonstrates that the ftt is able to reconstruct the vertex position reliably for single track events with small combinatorical background. d. . luminosity runs the performance of the trigger with respect to the background rejection and effi- ciency is tested using ep data. for these dedicated test runs the filtering on trigger level was switched off (transparent runs). in figure d. the distribution of the offline reconstructed z vertex is shown for an event sample triggered with the level subtrigger s , which requires a scattered electron (see section . . for the trigger conditions). as the veto conditions are switched off for these runs, a background ftt bin o ff li n e v e rt e x [c m ] - - - - figure d. : correlation plot of offline measured z vertex and online measured top peak position for cosmic events. ftt bin # e v e n ts figure d. : overlay of vertex histograms for ideal single track cosmic events. each individual histogram contributing is shifted to the central bin (see text). the binwidth is cm. peak is visible in the backward region of the detector. this peak contains about the same number of events as the signal peak due to the bad background conditions. in the same plot this distribution is shown if the trigger element te (significance method) is required. a large part of the background peak is rejected (about %), whereas only a small fraction of about % of the signal peak is rejected. this analysis was preceeded by detailed simulation studies on ep data [ ]. the pre- dicted rejection power of the z vertex trigger is shown in figure d. for a method very similar to the implemented significance method. a comparison to figure d. shows that the predicted background rejection was achieved for the implementation of the algorithm. the implemented methods are compared in figure d. . the maximum rejection is achieved for the significance method. the width of the signal window influences the rejection for the backward region. as expected, the largest rejection is achieved for the smallest signal window (top peak method). for all methods, the signal window is asymmetric and extends to + cm in the forward direction. the reason is a secondary vertex peak in the forward direction, which results from secondary tracks induced by particle showers. this peak often exceeds the primary vertex peak which results in a rejection of signal events if the signal window does not cover the forward region. the efficiency for the signal region is comparable for all methods. this was checked using samples of elastic and inelastic j/Ψ events which provide an ideal ep-signal. the selection was performed using the j/Ψ finder algorithm, both tracks belonging to the j/Ψ meson are required to be identified as an electron or muon. for the elastic sample no other tracks are allowed, for the inelastic sample the inelasticity is restricted to the range . < z < . , the center of mass energy in the photon proton system to the range < wγp < gev. in figure d. the invariant mass distribution is shown for both samples and compared to the distribution with the requirement of trigger element (significance method). only minimal losses due to the z vertex condition are desirable, the measured efficiency is about %, which is still acceptable. the performance of the ftt z vertex trigger is compared to the cip z vertex trig- ger, again using the s triggered data sample. the result is shown in figure d. . whereas the rejection of the ftt is about % for the background region, the cip trigger rejects almost every event for this region. the difference for the signal region is smaller, nevertheless the performance of the cip z vertex trigger is superior. the ftt has a better rejection power for the forward region. - - - - # e ve n ts with ftt zvtx condition zvtx [cm] z [cm] - - - - offline reconstructed vertices of: events with no vertex peak events triggered by the / peak method events vetoed by ftt figure d. : upper plot: z vertex distribution for s triggered events and for the additional z vertex trigger requirement. this data sample was taken at the end of a fill using dedicated trigger conditions, avoiding the rejection of background at other trigger levels. lower plot: z vertex distribution showing the predicted rejection power of the z vertex trigger as result of simulation studies (from [ ]). offline zvtx [cm] - - - - -r e je c ti o n . . . . . . . . . toppeak toppeak toppeak significance figure d. : comparison of the rejection power for different z vertex trigger ele- ments. inv. mass [gev] . . . . . . . . # e v e n ts with ftt zvtx condition inv. mass [gev] . . . . # e v e n ts with ftt zvtx condition figure d. : invariant mass distribution of a elastic (left) and inelastic (right) j/Ψ-sample with and without requiring the z vertex condition. offline zvtx [cm] - - - - -r e je c ti o n . . . . cip ftt figure d. : comparison of the rejection power for the ftt and the cip z vertex trigger. list of figures . deep inelastic electron-proton scattering at hera . . . . . . . . . . proton structure function f . . . . . . . . . . . . . . . . . . . . . . virtual corrections to the gluon propagator . . . . . . . . . . . . . . running of the effective coupling constant αs . . . . . . . . . . . . . qcd compton processes . . . . . . . . . . . . . . . . . . . . . . . . . boson gluon fusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . gluon and valence quark densities . . . . . . . . . . . . . . . . . . . illustration of splitting functions . . . . . . . . . . . . . . . . . . . . gluon ladder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . diagrams for heavy quark production in the massive scheme . . . . . diagrams for heavy quark production in the massless scheme . . . . illustration of fragmentation models . . . . . . . . . . . . . . . . . . diagrams for semi-leptonic decays of beauty quarks . . . . . . . . . . illustration processes implemented in monte carlo generators . . . . hera accelerator . . . . . . . . . . . . . . . . . . . . . . . . . . . . technical drawing of the h detector . . . . . . . . . . . . . . . . . . inner part of the h detector . . . . . . . . . . . . . . . . . . . . . . radial view of the central tracking system . . . . . . . . . . . . . . . central silicon detector . . . . . . . . . . . . . . . . . . . . . . . . . . r-z view of the upper half of the liquid argon calorimeter . . . . . . illustration of the electromagnetic spacal . . . . . . . . . . . . . . . inner spacal region . . . . . . . . . . . . . . . . . . . . . . . . . . . illustration of the four parts of the central muon detector . . . . . . cross section view of an instrumented iron module . . . . . . . . . . tagging methods used at h and zeus . . . . . . . . . . . . . . . . event display of a dijet event with a muon identified in the central muon detector . . . . . . . . . . . . . . . . . . . . . . . δ distribution for the dis sample of the h muon+jet analysis . . . beauty quark event with d∗ and muon . . . . . . . . . . . . . . . . . summary of zeus photoproduction results . . . . . . . . . . . . . . h hera i photoproduction result for the muon+jets analysis . . . h hera i photoproduction result for the dijet analysis . . . . . . . differential cross sections for the h hera i dis anal- ysis [ ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . differential cross sections for the zeus hera i dis analysis [ ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . differential cross sections for the zeus hera ii dis analysis [ ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . results from the ua measurement . . . . . . . . . . . . . . . . . . . tevatron run measurements . . . . . . . . . . . . . . . . . . . . . recent measurement of beauty quark production from cdf for run data . . . . . . . . . . . . . . . . . . . . . . . . . . . beauty quark production measurement at the lep collider . . . . . processes in the breit frame . . . . . . . . . . . . . . . . . . . . . . . ratio of reconstructed to generated values as a function of the generated value . . . . . . . . . . . . . . . . . . . . . . . . . . comparison of the simulated z vertex distributions to the data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . control distributions for e − pz and the cluster radius . . . . . . . . q distribution for small values of q and impact pa- rameter distribution for the inner spacal region . . . . . . . . . . . . distribution of the reconstructed impact position of electrons in the spacal . . . . . . . . . . . . . . . . . . . . . . . . . . reweight factor applied to the monte carlo simulation as a function of θe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . control distributions for variables determined from the scattered electron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . control distribution for the variable y . . . . . . . . . . . . . . . . . φ distribution of the scattered electron . . . . . . . . . . . . . . . . . distribution of the bjorken scaling variable. . . . . . . . . . . . . . . linking probability between central track and iron track . . . . . . . distribution of the number of muon layers with a hit for the central region . . . . . . . . . . . . . . . . . . . . . . . . . . . distribution of the number of muon layers with a hit for the forward region . . . . . . . . . . . . . . . . . . . . . . . . . . distribution of the distance between first and last hit layer for the central region . . . . . . . . . . . . . . . . . . . . . . . . distribution of the distance between first and last hit layer for the forward region . . . . . . . . . . . . . . . . . . . . . . . pseudorapidity distribution for the selected muon . . . . . . . . . . . reweight factor applied to the monte carlo simulation as a function of ημ. . . . . . . . . . . . . . . . . . . . . . . . . . . . . azimuthal angle and transverse momentum distribu- tion of the muon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . invariant mass distribution of the elastic j/ψ sample . . . . . . . . . muon reconstruction and identification efficiency for the forward barrel . . . . . . . . . . . . . . . . . . . . . . . . . . . . muon reconstruction and identification efficiency for the forward endcap . . . . . . . . . . . . . . . . . . . . . . . . . . . . correction factors for the muon reconstruction and iden- tification efficiencies . . . . . . . . . . . . . . . . . . . . . . . . . . . polar angle distribution for the jet selection . . . . . . . . . . . . . . transverse momentum of the muon jet, multiplicity for jets fulfilling the jet selection criteria and number of particles belonging to the muon jet . . . . . . . . . . . . . . . . . . . energy flow distributions for the selected jet . . . . . . . . . . . . . . number of selected events per inverse picobarn luminosity . . . . . . prelt distribution for the selected events . . . . . . . . . . . . . . . . . prelt distribution for the highest momentum track with respect to the jet axis for a sample with no muon requirement . . . . comparison of the prelt shape for light and charm quark events . . . results of the prelt fits . . . . . . . . . . . . . . . . . . . . . . . . . . results of the prelt fits . . . . . . . . . . . . . . . . . . . . . . . . . . prelt -fits for different bins of the muon transverse momentum . . . . . resolution of the measured transverse momentum of the jet according to the monte carlo simulation . . . . . . . . . . . . efficiencies and purities for the different analysis bins . . . . . . . . . efficiencies and purities for the different analysis bins . . . . . . . . . comparison of prelt and p̃ rel t . . . . . . . . . . . . . . . . . . . . . . . polar angle resolution of the jet according to the monte carlo simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . calorimetric energy attributed to muons . . . . . . . . . . . . . . . . isolation criteria for muons . . . . . . . . . . . . . . . . . . . . . . . total cross section for four different quadrants of the spacal . . . . differential born level cross section as a function of q . . . . . . . . differential born level cross section as a function of log x . . . . . . . differential born level cross section as a function of ημ . . . . . . . . differential born level cross section as a function of pμt . . . . . . . . differential born level cross section as a function of pjett . . . . . . . differential born level cross section as a function of q . . . . . . . . differential born level cross section as a function of log x . . . . . . . differential born level cross section as a function of η . . . . . . . . . differential born level cross section as a function of pμt . . . . . . . . differential born level cross section as a function of pjett . . . . . . . double differential born level cross section as a function of pjett . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . double differential born level cross section as a function of the scaling variable x . . . . . . . . . . . . . . . . . . . . . . . . . double differential born level cross section as a function of pjett . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . double differential born level cross sections as a func- tion of log x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . comparision of double differential cross sections mea- sured in the breit frame to the published hera i mea- surement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . comparision of double differential cross sections mea- sured in the breit frame to rapgap monte carlo pre- diction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . cross section measurements as a function of the muon transverse momentum . . . . . . . . . . . . . . . . . . . . . . . . . . cross section measurements as a function of the muon pseudorapidity . cross section measurements as a function of q . . . . . . . . . . . d. event display of background event . . . . . . . . . . . . . . . . . . d. radial view of the ftt . . . . . . . . . . . . . . . . . . . . . . . . d. geometry of the cjc . . . . . . . . . . . . . . . . . . . . . . . . . . d. z patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. illustration of a φ sector . . . . . . . . . . . . . . . . . . . . . . . . d. sketch of the z-linking process . . . . . . . . . . . . . . . . . . . . . d. overview of the ftt l trigger system . . . . . . . . . . . . . . . d. picture of a front end module . . . . . . . . . . . . . . . . . . . . . d. picture of a multipurpose processing board . . . . . . . . . . . . . d. apex k device block diagramm . . . . . . . . . . . . . . . . . d. difference of samples method . . . . . . . . . . . . . . . . . . . . . d. illustration of the charge integration method . . . . . . . . . . . . . d. illustration of ftt wires . . . . . . . . . . . . . . . . . . . . . . . . d. drift spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. functional design of the segment finding unit of the back fpga . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. principle of the pattern . . . . . . . . . . . . . . . . . . . . . . . . d. illustration of the vertex histogram . . . . . . . . . . . . . . . . . . d. correlation plot for cosmic events . . . . . . . . . . . . . . . . . . . d. overlay of vertex histograms for ideal single track cos- mic events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. z vertex distribution for s triggered events and pre- dicted rejection power . . . . . . . . . . . . . . . . . . . . . . . . . d. comparison of the rejection power . . . . . . . . . . . . . . . . . . d. invariant mass distribution of an elastic and inelastic j/Ψ-sample . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d. comparison of the rejection power for the ftt and the cip z vertex trigger . . . . . . . . . . . . . . . . . . . . . . . . . . list of tables . properties of some heavy hadrons . . . . . . . . . . . . . . . . . . . . parameters of hera ii . . . . . . . . . . . . . . . . . . . . . . . . . list of the main detector components of h . . . . . . . . . . . . . . the main component of the central h tracker and backward calorimeters . . . . . . . . . . . . . . . . . . . . . . . . . . different run ranges and corresponding luminosities. . . . . . . . . . trigger elements of subtrigger s . . . . . . . . . . . . . . . . . . . . monte carlo sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . parameters of the z vertex distributions . . . . . . . . . . . . . . . . dis selection cuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . muon selection cuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . muon reconstruction and identification efficiencies . . . . . . . . . . cuts for the j/ψ selection . . . . . . . . . . . . . . . . . . . . . . . . jet selection cuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . summary of all selection cuts that define the kinematic range of this analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . summary of the different error sources contributing to the systematic uncertainty . . . . . . . . . . . . . . . . . . . . . . . . parameters used for the different theoretical predictions for beauty quark production from lo monte carlo gen- erators and a nlo program. . . . . . . . . . . . . . . . . . . . . . . a. list of excluded runs . . . . . . . . . . . . . . . . . . . . . . . . . . a. list of requested detector components for the run selection . . . . c. differential cross sections for the process . . . . . . . . . . . . . . . c. differential cross sections as a function of the transverse momentum of the jet . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the transverse momentum of the jet . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the transverse momentum of the jet . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the scaling variable x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the scaling variable x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the scaling variable x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the scaling variable x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c. differential cross sections as a function of the scaling variable x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of ημ, pμt and p jet t . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of q and log x . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of pjett . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of pjett . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of pjett . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of log x . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of log x . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of log x . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of log x . . . . . . . . . . . . . . . . . . . . . . . c. predictions from next-to-leading order qcd calcula- tions as a function of log x . . . . . . . . . . . . . . . . . . . . . . . d. front fpga to back fpga protocol . . . . . . . . . . . . . . . . . d. cjc merger input . . . . . . . . . . . . . . . . . . . . . . . . . . d. sequence of sending data from fem to merger . . . . . . . . . . . d. fem-merger protocol . . . . . . . . . . . . . . . . . . . . . . . . . d. merger-z-trigger protocol . . . . . . . . . . . . . . . . . . . . . . . d. sequence 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[ ] t. wolff, entwicklung, bau und erste ergebnisse eines totzeitfreien spurfinders als trigger für das h -experiment am hera speicherring, phd thesis, swiss federal institute of technology zurich, . danksagung ich habe vielen personen zu danken, die einen beitrag zum zustandekommen dieser arbeit geleistet haben. frau prof. dr. b. naroska, die den abschluss dieser arbeit leider nicht mehr er- leben konnte, hat den mit abstand größten beitrag geleistet. ich bedanke mich bei ihr für das vertrauen und die möglichkeit, die promotion am h experiment durchzuführen. mit ihrem anhaltenden interesse, unermüdlichen einsatz und ver- antwortungsbewusstsein bis zum schluss wird sie mir als ein großes vorbild in erin- nerung bleiben. dr. benno list danke ich für die betreuung der analyse, das korrekturlesen der arbeit und die übernahme des gutachtens. bei prof. dr. klanner bedanke ich mich für seinen einsatz für die abschlussfi- nanzierung der arbeit, das schnelle und gründliche korrekturlesen der arbeit und die übernahme des gutachtens. prof. dr. schleper und dr. hannes jung danke ich für die bereitwillige übernahme des disputationsgutachtens. bei dr. olaf behnke bedanke ich mich für das interesse an der analyse und die beruhigenden, pragmatischen kommentare. dr. andré schöning danke ich für die möglichkeit, am ftt projekt mitzuarbeiten. ich konnte in dieser zeit viel von dr. niklaus berger lernen und habe von seinen vorarbeiten profitiert. bei michael und mira bedanke ich mich für die gute zusammenarbeit während der datenanalyse. miras positive einstellung hat zu einer entspannten, positiven büroatmosphäre beigetragen. bei shiraz bedanke ich mich für das korrekturlesen von teilen der arbeit. besonders wichtig ist es mir, tobias und den anderen diplomanden, doktoranden und post-docs der eth-zürich-gruppe in hamburg, giom, lea, michel, nik und ron, für die freundliche aufnahme während des ftt-projektes, die gute zusamme- narbeit auch danach und die vielen privaten unternehmungen zu danken. black skin and the ideal of beauty vol. . no . m ay t y table i. microsatellite instability in neurofibromas of two related nf-l patients" marke rs t t t t d s + s + + + s + + d s + s + + d s + a thre e nc urofi bro m bs oc th e fat h e r (t i. t . t ) and onc of th e d aug hte r (t ) were anal y z e d at l i cros< cclli tc lo c i . altered mi c ro satc llitc l l;lrkc rs are shown . sug g ests that this ge n e tic ev ent m ay b e ch ara cte ri sti c o f tb e late stages of tumor d evelo pm ent. on th e other hand , th e in cr eas ed susceptibility to e n vironm ental facto rs, pro ba bl y inv o lve d in n e u- rofi broma tumoli ge n es is, ma y al so ex pl ain di fie re n ces b e tw ee n individuals . m ultipl e ge n es r esp o nsibl e fo r se ve ral ge n o de rma toses ha ve be en recentl y m appe d on chromo so m e (pe ri cak-van ce ef ai , ). ou r findin g o f multiple alterations o n chro m oso m e indi cates that " m o difying ge n es" (easton et ai, ) , unlinked to th e nf- loc u s an d loca ted in th e r egio n s w e anal yze d , mi ght ha ve a r ole it) th e path ogen esis of n e uro fibr o ma s in nf-l pati e nts. f urth e r in ves ti ga- letters t o t he ed itor tio n s o n a large r numb er of n f-l p atients ar e n ee d ed to claj.i fy th e p rec is e rol e o f chro m oso m e in th e d eve lo pm en t of th ese tumors . m ali a con cett a farg n oli , sergio c himen ti , ke t ty pelis d ep artm ent of derm ato logy unive rsity of l' aq uil a, l' a quil a, ital y refer e n ces easto n df, po de r ma . hu so n sm , po n de r haj: an alla lys is ofv;lriauon in exp ress io n of n c u fo fibro m :tcosis (n f) ryp e . (nf l ): ev idence fo r m od ifyi n g gcn es . . j huiii cm et : - , t h on chel r . hallin g kc , pitte lkow m. sch aid oj, t hi bod eau sn : m icrosa telli rc in s t ~lbiljry in m uir-torre syndro m e . gnll re,. res - : l t - ' . j -t h oll c hc it . h all ing k c . thi bo d eau sn : gen o m ic in sti b ility in i co pla sin. scmill cel l bioi : - . ottini l. espo siro d l, r.ic he l ta a. cn rl csil l o m. p" llll.iro tra r. veri m c. bat ti sfa p. f rad l. ca rami a fg. c alv ic ri s, c,lm a a, mariani- c o stan tin i it: al te rn tion s o f m ic rosatc lli ces in ne u roftb ro m as o f voli r cc kjin g< u sc ll 's d ise ase . c allce,. res : - . pe ricak - va nc e ma . ba le ae, h aine s jl, kwiarko w ski d.i . pil z a , slau gc nh au pt s , w hite j a. edward s jh . ma rc hu k o. olopa de . attwoo d .l , povey s: r.epo rt o n the fo urth w o rksho p a ll c hro m o so m c . a iiii h i/iii g elll'l : - - - , pc ris k. ke ll e r g , c him c n ti s. a m semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /mtm. . corpus id: transcriptionally regulated and nontoxic delivery of the hyperactive sleeping beauty transposase @article{cocchiarella transcriptionallyra, title={transcriptionally regulated and nontoxic delivery of the hyperactive sleeping beauty transposase}, author={fabienne cocchiarella and m. latella and v. basile and f. miselli and m. galla and carol imbriano and a. recchia}, journal={molecular therapy. methods & clinical development}, year={ }, volume={ } } fabienne cocchiarella, m. latella, + authors a. recchia published biology, medicine molecular therapy. methods & clinical development the sleeping beauty (sb) transposase and, in particular, its hyperactive variant sb x raises increasing interest for gene therapy application, including genome modification and, more recently, induced pluripotent stem cells (ips) reprogramming. the documented cytotoxicity of the transposase, when constitutively expressed by an integrating retroviral vector (irv), has been circumvented by the transient delivery of sb x using retroviral mrna transfer. in this study, we developed an… expand view on pubmed cell.com save to library create alert cite launch research feed share this paper citationsbackground citations view all figures and topics from this paper figure figure figure figure figure view all figures & tables hyperactive behavior transposase tetracycline adverse reaction to drug induced pluripotent stem cells retroviridae trans-activators keratinocyte green fluorescent proteins reprogram citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency going non-viral: the sleeping beauty transposon system breaks on through to the clinical side m. hudecek, z. izsvák, s. johnen, m. renner, g. thumann, z. ivics biology, medicine critical reviews in biochemistry and molecular biology pdf view excerpt, cites background save alert research feed crispr/cas -mediated in situ correction of lamb gene in keratinocytes derived from a junctional epidermolysis bullosa patient. daniela benati, francesca miselli, + authors a. recchia biology, medicine molecular therapy : the journal of the american society of gene therapy save alert research feed references showing - of references sort byrelevance most influenced papers recency avoiding cytotoxicity of transposases by dose-controlled mrna delivery m. galla, a. schambach, + authors c. baum medicine nucleic acids research pdf save alert research feed sleeping beauty transposition from nonintegrating lentivirus. c. vink, h. gaspar, + authors w. qasim biology, medicine molecular therapy : the journal of the american society of gene therapy save alert research feed development of hyperactive sleeping beauty transposon vectors by mutational analysis. h. zayed, z. izsvák, oliver walisko, z. ivics biology, medicine molecular therapy : the journal of the american society of gene therapy save alert research feed genomic analysis of sleeping beauty transposon integration in human somatic cells giandomenico turchiano, m. latella, + authors a. recchia biology, medicine plos one pdf save alert research feed integration profile and safety of an adenovirus hybrid-vector utilizing hyperactive sleeping beauty transposase for somatic integration w. zhang, martin muck-hausl, + authors a. ehrhardt biology, medicine plos one pdf save alert research feed comparative genomic integration profiling of sleeping beauty transposons mobilized with high efficacy from integrase-defective lentiviral vectors in primary human cells. brian moldt, c. miskey, + authors j. mikkelsen biology, medicine molecular therapy : the journal of the american society of gene therapy save alert research feed duration of expression and activity of sleeping beauty transposase in mouse liver following hydrodynamic dna delivery. j. b. bell, e. aronovich, jeffrey m. schreifels, t. beadnell, p. hackett biology, medicine molecular therapy : the journal of the american society of gene therapy save alert research feed the hyperactive sleeping beauty transposase sb x improves the genetic modification of t cells to express a chimeric antigen receptor z. jin, s. maiti, + authors l. j. cooper biology, medicine gene therapy pdf save alert research feed molecular evolution of a novel hyperactive sleeping beauty transposase enables robust stable gene transfer in vertebrates l. mátés, m. chuah, + authors z. izsvák biology, medicine nature genetics pdf save alert research feed sleeping beauty transposition: biology and applications for molecular therapy. z. izsvák, z. ivics biology, medicine molecular therapy : the journal of the american society of gene therapy save alert research feed ... ... related papers abstract figures and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue breast surgery – a problem of beauty or health? uva-dare is a service provided by the library of the university of amsterdam (https://dare.uva.nl) uva-dare (digital academic repository) breast surgery: a problem of beauty or health? benditte-klepetko, h.c. publication date link to publication citation for published version (apa): benditte-klepetko, h. c. 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chapter ii hypertrophy of the breast: a problem of beauty or health? heike ch. benditte-klepetko valerie schickl tatjana paternostro monika rakos thomas helbich siegfried trattnig michael schemper maria deutinger department of plastic and reconstructive surgery | krankenanstalt rudolfstiftung department of rehabilitation | medical university of vienna department of radiology | medical university of vienna institute of computer sciences | medical university of vienna vienna, austria journal of women’s health ( ): - , hypertrophy of the breast: a problem of beauty or health? introduction the most common symptoms of women suffering from breast hypertrophy are mal-posture, painful shoulder grooves, submammary intertrigo and back pain - . furthermore different authors reported upper extremity neurologic symptoms caused by excessive breast size, like ulnar nerve paresthesias , hand numbness and carpal tunnel syndrome . these findings may result from brachial plexus com- pression between the coracoid process of the scapula and the rib cage as forward depression of the shoulders tilts the coracoid downward . starley et al. reported reduction of lung function, suggesting that a heavy breast mass leads to decreased chest wall compliance. in addition to these physical symptoms, macromastia has cosmetic and psycho- logical components. the breast plays an important role in female self-confidence. therefore breast hypertrophy is associated with heightened body image dissatis- faction. patients may have decreased self-confidence due to difficulties while exer- cising, problems finding properly fitting clothes or impaired personal relationships and social life - . a detailed overview of the literature was given recently by young and watson . they conclude, that the majority of women with macromastia pursue breast reduc- tion surgery to relieve the physical symptoms, which also interfere with the ability to keep up daily life activities. but young and watson also point out that especially young women may be more strongly motivated to have surgery because of psy- chosocial concerns, although they suffer from physical problems. young women tend to adopt strategies to camouflage their breasts and the emotional and social repercussions of abnormally large breasts in adolescence may resonate throughout adulthood. as young and watson discuss, complaints about physical symptoms are more often voiced by older women, perhaps because of the accumulated years of carrying heavy weight on the chest, which can place unnatural loading on the upper body . because of this complex health burden for women with breast hypertrophy, reduction mammoplasty is considered reconstructive in nature and is the most common operation on the female breast in plastic surgery today. with a rate of up to . in , women it ranks among the top five reconstructive procedures . in , . breast reduction procedures were performed in the united states by board-certified plastic surgeons . on the other hand, cosmetic surgery procedures have increased at a dramatic rate , since the enigma of beauty is epitomised in our culture. but, cosmetic sur- gery is excluded from service contracts. selective access policies are designed to restrict expenditure on certain procedures, and non-urgent plastic surgical cases, chapter ii such as breast reduction, have become targets. beside the fact that the official definition of reconstructive surgery by the american society of plastic surgeons considers reduction mammoplasty to be reconstructive in nature , the general public and many medical professionals consider reduction mammoplasty to be more a cosmetic than a functional operation. as a result, insurers do not accept that symptomatic macromastia is a significant health burden. unfortunately, denials of insurance coverage and policy exclusions for breast reduction are becoming increas- ingly common in europe as well as in the united states , , and the justification for outright rejection of funding is often unknown . although previously published longitudinal studies showed that reduction mammoplasty will reliably provide the desired improvement of all symptoms and improvement in the quality of a women’s life - , , a continuous discussion is ongoing about whether reduction mammoplasty is a cosmetic or reconstructive procedure. to elucidate this question the aim of our study was to demonstrate using reliable measurements the influence of breast weight on the physical and psychological morbidity of women. materials and methods study design and population we performed a cohort study of women with various breast sizes, a mean age of years (range: – years, sd: . ) and a body mass index (bmi) less than (mean: . , sd: . ). the women were recruited from nurses of our department, medical students and women consulting our outpatient clinic for breast reduction surgery as well as other reasons. a balanced representation of individuals with re- spect to cup-size (a-c vs. t d) and age ( - years vs. – years) was achieved. in order to reduce the confounding effect of overweight, the body mass index had to be less than according to the national heart, lung and blood insti- tute criteria (normal < kg/m , overweight – , kg/m , obese > kg/m ). also women with traumatic or other known spine diseases were excluded from the study. all women were caucasian, well educated (at least years of education) and employed. all women were asked for participation without payment. the women with hypertrophic breasts were specifically told that the responses given in this study were confidential and would not impact on their treatment, thus eliminating any possible confounding motive in their responses. hypertrophy of the breast: a problem of beauty or health? local ethics committee approval was obtained and all women had to give in- formed consent to participate under the guidelines of the local ethics committee. the following data were obtained: breast volume, magnet resonance imaging of the spine, physical examination and interview as described below. volumetric measurement of the breast a specific device based on the principle of water displacement was constructed by technicians of the department of biomedical engineering and physics of the medical university of vienna. the amount of displaced water was weighted and multiplied by a breast tissue specific factor (mass density of breast tissue = kg/m ) . the validity and reliability of this method was demonstrated in previous studies. for statistical analysis the weight of both breasts was added. magnetic resonance imaging (mri) of the spine degenerative changes in the cervical and thoracic discs were studied by mri and evaluated by loss of signal characteristics, posterior and anterior disc protrusion, narrowing of the disc space and foraminal stenosis. we examined the alignment for deviations in the frontal and sagittal plain. for mri a . t scanner (magnetom vision, siemens, erlangen, germany) with a phased array spine coil was used. we obtained localiser sequences in the coronal plane for planning the sagittal and axial sequences. the following sequences were applied: sagittal t -fse (tr/te: / ms; turbofactor: ), sagittal t -fse (tr/te: / ms; turbofactor: ). for both sequences the matrix size was x mm, field of view: x and the slice thickness mm. additionally, an axial fisp- d sequence (tr/te/flip-ankle: / / °) was performed. for this sequence the matrix size was x mm, the field of view: and the slice thickness mm. for statistical analyses pathological findings were graded as and , for degen- erative and no changes, respectively. the assessments were made blindly by two independent, experienced radiologists. functional evaluation of the spine to evaluate the functional status of the spine a grading system was used, based on the assessment of posture, mobility of the cervical spine, muscular dis-balance and musculoskeletal pain. according to the specific symptoms described for women with high breast weight , it was looked for the presence of scoliosis, the presence of deviated head position, the presence of shoulder protraction in habitual or cor- rected sitting position, the shortening of the pectoralis muscles, the strength of the abdominal muscles and back extensor muscles. the mobility of the cervical spine chapter ii was measured by a hand goniometer according to the neutral-zero method and the muscle strength of the abdominal wall and the back extensors was obtained using janda’s and kendall’s standardised grading scale (table ). scoliosis, spine deviation in the sagittal plane and head posture were assessed in standing position. a spine deviation was scored as , no deviation as . a correct head posture was assumed if the meatus acusticus externus was in ligne with the hip joint axis. any deviation to the front was regarded as deviation of the correct head position and was scored as , no deviation as . shoulder protraction was assessed in sitting position. shoulder position was described as being protracted (score ) or normal (score ). for measurements of the length of the pectoralis muscle the woman was lying supine, elevating the arms over the head. shortening was assumed when the arms did not reach the table and scored as . normal length was considered . cervical spine mobility was assessed for the sitting patient. restricted cervical spine mobility was scored as , unrestricted as . for muscle strength assessment of the abdominal wall the woman was lying supine, strength was assessed according to janda’s grading system from to (grade stands for normal strength and grade for highly reduced strength). for the spine score in our study grade was scored as and grade as . for muscle strength assessment of the back extensors according to kendall’s strength grades were scored from (highly reduced strength) to (normal strength). maximum score was . the higher the score, the higher was the functional impairment of the spine. all measurements were performed by a single physical therapist. table . “spine score”: grading system for the functional status of the spine, maximal total score = hypertrophy of the breast: a problem of beauty or health? pain intensity a visual analogue scale (vas) was used to quantify pain intensity. this scale consists of a -cm line with each centimeter numbered to . at the left ( ), the words “no pain” are typed, and at the right ( ), the words “worst possible pain” are typed. the patient is asked to mark on the scale an estimation of their current level of pain . assessment of depressive symptoms all women completed the beck depression inventory (bdi). the beck depression inventory defines grades of depressive symptoms by a scoring system: . no depression (score d ) . mild depression (score – ) . severe depression (score t ) statistical analyses the effects of age, breast weight and bmi on pathologic findings in the mri were quantified and tested for significance by means of multiple logistic regression analy- sis. associations of bdi and spine-score values with other patient characteristics were quantified and tested for significance by spearman correlation coefficients. partial spearman correlations served to eliminate the effect of bmi and age on correlations of bdi and spine-score values with breast weight. all statistical analyses utilised programs of sas (sas institute, cary, nc, usa). results breast weight measurement a median total breast weight of both breasts of g was found (range: – g). the correlation of breast weight to the bra-cup size is shown in figure . concerning the definition for breast hypertrophy, as reported in the literature by cup size d or larger, the corresponding breast weight for the smallest cup size d was g. the mean bmi of all women was , kg/ m (range: - kg/m ). table shows that the breast weight is correlated with the mri-score, the spine score, pain, bdi, age and bmi. adjustment of these correlations by age and bmi did neither substantially modify correlations or p-values. chapter ii mri of the cervical and thoracic spine in out of women a pathologic mri result was found. in woman a disc- protrusion beyond the margin of the vertebral bodies was seen. women had a disc-protrusion within the anterior margin of the vertebral bodies. in women other degenerative abnormalities were found. for the mri-score we observed a statistically significant correlation with breast weight, spine-score, pain bdi and bmi. between mri-score and age no significant correlation was detected. after adjustment of these correlations by age and bmi the correlation of mri-score and bdi is not significant anymore, which might show the influence of bmi on these parameter (table ). figure . breast weight of all individuals included in the population according to bra size table . upper triangle: spearman correlations of all variables considered, lower triangle: partial spearman correlations of the variables considered, adjusted for age and bmi hypertrophy of the breast: a problem of beauty or health? multiple logistic regression analysis (using breast weight, age and bmi as predic- tors) gave evidence that the independent effect of breast weight on pathologic findings in the mri is confirmed (p= . ), as is the effect of age (p= . ). in addi- tion to age and breast weight, the body-mass-index was of no predictive relevance (table ). for each additional years the relative risk to develop a degenerative spine dis- order increases . fold and for each additional kg of breast weight . fold. the resulting probabilities for degenerative spine disorders are summarised in table and the effect of breast weight by age are plotted in figure . spine score in the whole cohort the mean score of functional impairment of the spine was . (range: – ). the statistical analysis of the data by the spearman correlation coef- ficient “r” showed a significant correlation between the spine score and the bmi as well as the breast weight, the mri-score, the bdi and the pain defined by the visual table . effect of the three most important factors for degenerative spine disorders classified by mri according to multiple logistic regression. figure a & b. degenerative morphological changes ( a) and a prolapse of an intervertebral disc ( b) shown by mri in women with breast hypertrophy. chapter ii analogue scale vas, which does not change after adjustment for age and bmi. in our selected group no significant correlation was found between the spine score and age (table ). back pain the mean cumulative visual analogue scale score for all participants was . (range, - ). the unadjusted spearman correlation coefficient “r” showed significant cor- relation between pain and breast weight, mri-score, spine-score, bdi and bmi. these correlations are not changed by adjustment for age and bmi (table ). beck depression scale out of women showed symptoms of a mild or severe depression analogue to the beck depression inventory. out of had signs of a mild (score - ), out of of a severe (score >/= ) depression (mean: . , sd: . ). the statistical analysis by the spearman correlation coefficient showed a significant correlation of the score of depressive symptoms and all other measured parameters beside age. adjusted for age and bmi there was no further significant correlation found between the value of depressive symptoms and the mri score (table ). discussion this cohort study demonstrates the impact of breast weight on the morbidity of – year old women. in particular, the results of pathologic findings in the mri show conclusively the increased risk of developing a spine disorder in women with heavy breasts. the risk has been shown to be related to the patients’ age , but additionally the risk is , times higher per kilogram of increased breast weight. as an example, the corresponding probability of developing a spine disorder for a -year-old woman with g breast weight (cup size b) is %; for -year-old woman with g breast weight (cup size d) it is %. compared to this the risk for a -year-old woman with g breast weight is % and for a -year-old woman with g breast weight it is % (fig. ). by using standardised muscle and posture testing we have shown the morpho- logic changes caused by increased breast weight and a validated pain scoring dem- onstrated the high level of pain in woman with heavy breasts. our results, similar to those published by chao et al. illustrated the functional disability in patients with macromastia. hypertrophy of the breast: a problem of beauty or health? additionally, the psychological impairment caused by increased breast weight was demonstrated by the high incidence of depressive symptoms in heavy breasted women by means of the beck depression inventory. our data show that body weight as measured by body mass index also has an impact on development of spine disorders, mal-posture and depressive symptoms. a correlation between obesity and depressive symptoms had been previously de- scribed . therefore we suggest that weight reduction might support risk reduction. however, it is notable that glatt et al. found that symptom relief and improved body image occurred after breast reduction independently of preoperative body weight. in addition, there is a high prevalence of obesity in patients seeking breast reduction and these women also benefit from breast reduction surgery, as reported by collins et al. . weight seemed to have an influence on all parameters, but by excluding obese women from this study and adjusting the analysis of the effect of breast weight on bmi, the confounding effect of weight was avoided. as a result our cohort might be not representative for the typical population of women seeking breast reduc- tion, but by focusing on the effect of breast weight, it was necessary to exclude obese women from the study. for the same reason, women older than years were excluded from the study, since age has a well known impact on spine pathol- ogy. as our data show an effect of age on pathologic findings in the mri even in women younger than , we believe older women might benefit from reduction mammoplasty. a further study of a larger number of women, including obese women and women older than , would allow this issue to be proved statistically. figure . estimated probabilities for degenerative spine disorders (as diagnosed by mri), effect of breast weight and age. line : gr/ years old: risk %; gr/ years old: risk %. line : gr/ years old: risk %; gr/ years old: risk %. chapter ii limitations of our study include the small sample size, as well as the predomi- nantly affluent caucasian population that comprises the study cohort. further study of a more racially and economically diverse population may be warranted. thus far no definite breast weight has been defined at which reduction mammoplasty is necessarily indicated to prevent a subsequent morphological or psychological disease. apart from those insurance companies that do not cover the procedure at all, most companies reimburse the cost of a resection involving more than g tissue per breast. kerrigan et al. stated that a woman with cup-size d or larger would benefit from breast reduction surgery. our data show that the minimum breast weight of a breast with cup-size d is approximately g per side compared to approximately g in a breast with cup-size b. therefore, we suggest that g is a reasonable weight of tissue to remove in women with cup size d or larger. nevertheless, we emphasise that declaring a minimum of g resection-weight per breast to differentiate between cosmetic and reconstructive indications might be disadvantageous to very small and slim women. for this reason schnur et al. as well as kompatscher et al. calculated scales of individual specimen weight limits for a reconstructive indication in breast reduction operations adapted to the indi- vidual patients body proportions. as stated by collins et al. it makes more sense to use the physical symptoms of the patients as the criteria for insurance coverage instead of the amount of removed tissue. the question arises if nonsurgical interventions could be an alternative to reduc- tion mammaplasty. to answer this question collins et al. performed a prospective study comparing a surgical intervention group with a group including women with hypertrophic breasts and a control group of women with cup-size < d. in this study, conservative measures such as weight loss, physical therapy, special brassieres and medications did not provide sufficient and permanent relief of symptoms in patients with macromastia. conclusions these data give the objective evidence that breast weight has an influence on the physical and psychological morbidity of women, and therefore challenges the basis for resource allocation decisions with regard to breast reduction surgery. the results should guide insurance companies to establish a uniform and ap- propriate selection procedure that ensures equitable access. hypertrophy of the breast: a problem of beauty or health? references . glatt bs, sarwer db, o’hava de, hamori ch, bucky lp and larossa d: a retrospective study of changes in physical symptoms and body image after reduction mammaplasty. prs / : - , . gonzales f, walton rl, shafer b, matory we, borah gl: reduction mammaplasty improves symptoms of macromastia. plast reconstr surg : - , . blomqvist l, eriksson a, brandberg y: reduction mammaplasty provides long-term improve- ment in health status and quality of life. plast reconstr surg : , . mizgala cl, mackenzie km: breast reduction outcome study. ann plast surg : - , 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- , . .j.ellc. . english language, literature & culture ; ( ): - http://www.sciencepublishinggroup.com/j/ellc doi: . /j.ellc. . issn: - (print); issn: - (online) commentary an analysis of “beauty of death” in edgar allen poe’s poetry jiaqi yin school of education, nanjing normal university, nanjing, china email address: to cite this article: jiaqi yin. an analysis of “beauty of death” in edgar allen poe’s poetry. english language, literature & culture. vol. , no. , , pp. - . doi: . /j.ellc. . received: march , ; accepted: march , ; published: april , abstract: edgar allen poe was one of the greatest poets in america and the poems he created have a great impact on not only american literature but the whole world. in many of his poems, “death” is almost everywhere, and through these poems his aesthetic view was revealed. in poe’s mind, the terror and ugliness of death is another form of beauty, and this sort of beauty is eternal and transcends time and space. the author analyzes different presentations of “beauty of death” in poe’s poems and finds that, in poe’s mind, death does not mean the end of life, but a kind of rebirth and a sublimation of soul, and it helps people to find the “supernal beauty” which only exists in another world. to explore this is of great value to study his extraordinary and unique poems and further explore his view of death and aesthetics. keywords: allen poe, poetry, death, beauty, aesthetics . introduction edgar allen poe ( — ) was one of the greatest and the most widely read writers in america, who had a deep influence on not only american literature but the world arena. just as hammond said, “poe is a poet in the first place and then a short story writer.” [ ] poe’s writing career began with poems and also ended with it, and he was also a prolific poet since his four collections of poems were published. however, although he devoted himself in writing, he did not get a foothold in mainstream american literature when he was alive. on the contrary, his life was filled with sneer and disesteem and he was not accepted by american literary circle at that time. to make things worse, poe’s beloved families passed away one by one, leaving him alone in this indifferent world, which led to his death at a young age. during poe’s lifetime, there were three important women who were muse in most of his poems. they are his mother, mrs stannard, and his wife virginia clemm. unfortunately, his mother died when he was very young. this tragedy leads to his desire for maternal love throughout his life, which is reflected in literary creation. it has been said that a series of his heroine such as ligeia, eleonora, berenice and lenore are modeled on his mother. mrs. stannard, poe’s classmate’s mother, was a beautiful, melancholy, sentimental and fragile woman who provided him with consolation, sympathy and maternal love. in poe’s mind, mrs stannard was his mother, his lover and his bosom friend. unfortunately, mrs. stannard died of tuberculosis, the disease same as his mother’s. to helen was to commemorate his “first and purest and ideal love” [ ] to this lady. poe’s wife, virginia clemm, was also tortured by tuberculosis and died at the same age as his mother. virginia was smart, beautiful and brave, and poe’s love to her had a love-like attachment to his mother. just like poe’s mother and mrs stannard, virginia was also the muse in many of poe’s poems, among which the most famous is annabel lee. these three important females’ deaths are undoubtedly a heavy blow to poe, which laid a deep imprint on his works. it is no wonder that poe was so sensitive to death and beauty. in poe’s poetry, aesthetics is the most important thing rather than profound thought and philosophy. poe thought that among all the melancholy topics, death was the saddest one and “the death of a beautiful woman is unquestionably the most poetical topic in the world”. [ ] thus, most of his works are dark and pessimistic, and his heroines are all beautiful, clever and kind, but no one escaped the fate of dying at a english language, literature & culture ; ( ): - young age. therefore, to analyze “death of beauty” not only is conductive to further understanding poe’s aesthetic view and exploring his artistic achievements, but has a guiding significance to study modern american poetry. . previous studies on allen poe in recent years, edgar allan poe has been always within the spotlight of critical attention and evaluation. just as t. s. eliot said, edgar allan poe was indeed “a stumbling block for the judicial critic.” studies on him covered many aspects, including biography, psychology, and his literary creations. in early years, most studies on him tried to probe into his personal life to find the root of his creations, such as hervey allan’s israfel: the life and times of edgar allan poe ( ) and arthur hobson quinn’s edgar allan poe: a critical biography ( ). in the first half of the twentieth century, critics turned to study his works, such as allan tate’s the angelic imagination ( ). d. h lawrence’s studies in classic american literature ( ). after that, critics began to analyze poe’s works from the perspective of structuralism, socialism, feminism and so on, such as david ketterer’s the rationale of deception in poe ( ) and leland s. person’s aesthetic headaches ( ). studies on poe in china began during “the may th ” period when the highly reputed chinese writer lu xun translated and introduced poe’s the gold-bug to chinese readers, and lu highly praised the effect of poe’s works. since then, more scholars began to read poe’s works and the aesthetic theories in poe’s work do have a profound impact on the formation and development of chinese modern poetry, especially the development of crescent school. however, for a long period, studies on poe in china remained on a superficial level as chinese scholars just either studied poe’s life or translated his works. fortunately, in the late s, more researches began to apply some literary theories to the analysis of poe’s works, and noticed the theme and the aesthetic value of poe’s poetry, such as zhu zhenwu and wang erlei [ ] who talk about poe’s aesthetic interest and his poetic theories in his poetry concerning death and dreams, and yu lei [ ] who analyzes the cognitive mechanism in poe’s fictional aesthetics and he also discusses four aspectes of edgar allen poe’s fictional aethestics [ ]. in addition, some chinese scholars compare poe with chinese poets. for example, zhang junru and zheng fei [ ] compare poe with haizi to analyze their view on death. liu shijun [ ] compare poe’s annabel lee with jiangchengzi which was written by sushi, a great chinese ci poet, to talk about the eternal and immortal love to their respective wife. after analyzing current studies on poe’s poetry in china, the author finds that although there is an increasing number of researches on poe’s view of death and his aesthetic view, few of them combine these two together. in this paper, the author will analyze three poems to conclude different presentations of “death of beauty” in poe’s poetry and his view of death and aesthetics, so as to better understand poe’s poetry and his profound impact on american literature. . different presentations of “beauty of death” in poe’s poetry “death” and “beauty” have always been the two major themes in poe’s poems. in poe’s poetry, “beauty” has always been closely linked to “death” in a melancholy and horrific atmosphere. different from traditional beauty which is pure and is usually linked with good morality, “beauty” in poe’s poetry tends to be absurd and creepy. . . the horrific and mysterious beauty of death death is undoubtedly the most horrible and mysterious thing in the world, and it appears repeatedly in poe’s poetry, forming a horrific and mysterious atmosphere. there are different kinds of horror in his poetry, such as the horror of death, the horror of disillusionment, and the horror of weirdness. horror in poe’s poetry is not only revealed from the words and senses, but emerges from the bottom of readers’ heart. in this way, the effect of horror is achieved and beauty of death is depicted. poe has a great number of poems that manifest horrific and mysterious beauty, such as the conqueror worm, ulalume and the city in the sea. the author will analyze the city in the sea to explore how poe manifests the horrific and mysterious beauty of death. lo! death has reared himself a throne in a strange city lying alone far down within the dim west, where the good and the bad and the worst and the best have gone to their eternal rest. there shrines and palaces and towers (time-eaten towers that tremble not!) resemble nothing that is ours. around, by lifting winds forgot, resignedly beneath the sky the melancholy waters lie. no rays from the holy heaven come down on the long night-time of that town; but light from out the lurid sea streams up the turrets silently— gleams up the pinnacles far and free— up domes—up spires—up kingly halls— up fanes—up babylon-like walls— up shadowy long-forgotten bowers of sculptured ivy and stone flowers— up many and many a marvellous shrine whose wreathed friezes intertwine the viol, the violet, and the vine. resignedly beneath the sky the melancholy waters lie. so blend the turrets and shadows there that all seem pendulous in air, while from a proud tower in the town death looks gigantically down. there open fanes and gaping graves yawn level with the luminous waves; but not the riches there that lie jiaqi yin: an analysis of “beauty of death” in edgar allen poe’s poetry in each idol’s diamond eye— not the gaily-jewelled dead tempt the waters from their bed; for no ripples curl, alas! along that wilderness of glass— no swellings tell that winds may be upon some far-off happier sea— no heavings hint that winds have been on seas less hideously serene. but lo, a stir is in the air! the wave—there is a movement there! as if the towers had thrust aside, in slightly sinking, the dull tide— as if their tops had feebly given a void within the filmy heaven. the waves have now a redder glow— the hours are breathing faint and low— and when, amid no earthly moans, down, down that town shall settle hence, hell, rising from a thousand thrones, shall do it reverence. [ ] there is a mysterious and unforgettable atmosphere in the city in the sea. something unknown is hidden in this seemingly peaceful sea, which is manifested as a mysterious and horrible scene. in this poem, sea is not just a background but is indispensable to form the whole picture. in the first section, poe first depicts a city which is “strange” and lies “alone”, in which the throne of “death” is erected. this provides readers with a horrible scene and arouses readers’ interest to explore this city. then, poe uses “far”, “dim” and “eternal rest”, all of which not only vividly depict a dark and cold atmosphere but also show that everything here is static just like “the melancholy waters lying resignedly beneath the sky”. however, this seemingly peaceful sea is going to have a striking change. in the second section, poe tells us that rays are not from “the holy heaven” but “the lurid sea”. these rays are not static but “streams up the turrets silently” and “gleams up the pinnacles far and free”. this scene undoubtedly shows that the sea is going to change. in addition, both of “the kingly hall” and “babylon-like walls” reveal the power of the invader. in the fourth section, poe also portrays that the sea is “less hideously serene” with “no ripple” and “no swellings”. but is it true? in the last section, the city is destroyed all of a sudden. poe depicts a “stir” in the air and a “movement” in the sea, and that “the tower had trust aside” and “the wave have a redder glow”. all of them lead to the sinking of the city, with which hell rises “from a thousand of thrones”. this perfectly echoes the first sentence “death has reared himself a throne”. poe successfully created a horrific and mysterious atmosphere by using different artistic techniques to illustrate the surrounding environment and the supernatural phenomenon. for example, he used personification in the sentence “the hours are breathing faint and low”, suggesting that the fainting time provides the sea with life and power to engulf the city. readers can imagine that a terrible monster with dark wings hovers in the vast sky, with its blue eyes staring at the vast sea to find treasures to build a palace for itself. in addition, poe also took advantage of the techniques of contrast and comparison to strengthen the horrific and mysterious “beauty of death”. . . the melancholy and romantic beauty of death in poe’s mind, the death of a beauty is undoubtedly the most poetic thing. in order to pursue “beauty” in poetry, poe portrayed a great many females in his poems, all of whom are beautiful, young, loyal to love, and are the representation of perfection. however, they all die in their bloom of youth and in the hug of love, which does not conform to the law of nature. these beauties are the true portrayal of those important females in poe’s life, like his mother, mrs stannard and virginia. it is easy for readers to be touched and immerse themselves in a sorrowful mood upon seeing the death of those beauties, for their death has a melancholy and romantic beauty. many of poe’s poems depict this kind of beauty, such as annabel lee, israfel, lenore, and his well-known poem the raven. the author will analyze the raven to explore how poe described the melancholy and romantic beauty of death in his poetry. “prophet!” said i, “thing of evil!—prophet still, if bird or devil! by that heaven that bends above us—by that god we both adore— tell this soul with sorrow laden if, within the distant aidenn, it shall clasp a sainted maiden whom the angels named lenore— clasp a rare and radiant maiden, whom the angels named lenore.” quoth the raven, “nevermore.” poe wrote this poem as a narrator and drew a melancholy picture. in a dreary and bleak midnight, the narrator just lost his beloved lenore. he is weak and weary and tries to indulge himself in the book to forget the pain, but in vain. suddenly, the narrator hear someone knocking at his door, and he wonders if it is his lenore. to his disappointment, it is just a raven. the narrator asks it about its name. it replies “nevermore”. then, the narrator asks whether it is the angel sent by god to give him nepenthe to respite and forget his lost lenore, and it replies “nevermore” again. the narrator asks it whether he can clasp lenore in “the distant aidenn”, but it replies “nevermore” again. when the narrator asks it to get back into “the tempest and the night’s plutonian shore”, it also replies “nevermore”. there are twelve “nevermore” in this poem, which implies that lenore will not come back and “my” soul will never be lifted. lenore and the narrator are separated by death, making him grief-stricken, frenzy and mad. traditionally, raven is regarded to be ominous and usually appears in cemetery. thus, the poem sets a melancholy, bleak and decaying tone and suggests the loss of lenore with the appearance of raven. just as poe said, the death of a beauty is the most poetic one. the death of this “sainted”, “rare and radiant” maiden reveals extreme beauty. in fact, the raven describes a dream in which the narrator’s pursuit of lenore is in vain. the loss of this angel-like lenore also implies the loss english language, literature & culture ; ( ): - of beauty. in this way, death is closely linked with beauty. readers will not only sigh for the loss of beauty but be easily touched by the romantic but grievous love between the narrator and lenore. between the lines, the poem sings the praise for the eternal romantic love, and at the same time, shows that the narrator is lingering between the reality and the dream in a melancholy mood. thus, a melancholy and romantic beauty of death is realized. . . the holy and transcending beauty of death poe was pursuing a “supernal beauty” throughout his life, which can only be realized via death because this beauty is spiritual freedom and rebirth of the soul. many of his poems manifest this sort of beauty, like tamerlane and to helen. the author will analyze to helen to explore how poe expresses this kind of beauty that is holy and transcends death. helen, thy beauty is to me like those nicean barks of yore, that gently, o’er a perfumed sea, the weary, way-worn wanderer bore to his own native shore. on desperate seas long wont to roam, thy hyacinth hair, thy classic face, thy naiad airs have brought me home to the glory that was greece, and the grandeur that was rome. lo! in yon brilliant window-niche how statue-like i see thee stand, the agate lamp within thy hand! ah, psyche, from the regions which are holy land! the whole poem is surrounded by an illusory misty and exotic aesthetic color. in the first line of the poem, the narrator declares that he is totally intoxicated with helen’s beauty, and the purpose of this poem is to praise this kind of beauty which can destroy a city or even a state. traditionally, helen is the embodiment of classical beauty in greek mythology. in this poem, poe does not mention helen’s life experience and social background, but depicts her beauty and her elegant temperament and demeanor with rich imagination and by the use of metaphor. helen’s beauty attracts the narrator and stimulates his sincere love to her, which is emanated from his soul. readers can imagine that when he wrote this poem, poe was totally immersed in the beauty of helen. in the second section, “i” can be considered as the poet himself because this set of images is also the description of poe’s unfortunate life. his father left him and his mother died when he was very young. thus, he was “wont to roam on desperate seas” and longed for maternal love. mrs stannard provided him with this sort of love and he devoted his loyal love to her in turn. in poe’s mind, she is the embodiment of perfection and has the same transcending beauty as helen in greek mythology. “thy hyacinth hair, thy classic face, thy naiad airs have brought me home” is not only praise for helen, but for mrs stannard. in addition, there are two implications in “have brought me home”. one is the literary meaning while the other is the metaphorical one. “i” understand that “the glory that was greece, and the grandeur that was rome” is actually a synonym for classical beauty. the poet linked helen’s hair, face and elegance with the splendor of greece and rome, which represents that helen’s beauty is sacred and immortal and will not fade away as time goes by. this suggests that mrs stannard is the embodiment of youth, pureness and transcending beauty. it is from mrs stannard that poe felt the holiness of this transcending beauty. in this poem, poe did not depict helen’s appearance meticulously, but compared her beauty with all kinds of images that transcend time and space, so as to show that her beauty is actually the sacred beauty of another world, a world one can reach only when he dies. in this way, a holy beauty is created which transcends the death of body. . the root of “beauty of death” in poe’s poems . . poe’s view of death thompson once said that allen poe is a “verbal landscapist of death” [ ]. in poe’s poetry, death, like a monarch, looks down on all the living things. although death is ugly and horrific, it is another form of “beauty” and “rebirth” under poe’s pen. just as the aesthetician dufrenne said that this kind of death may lead to “the regeneration of life and surrealism”. then a more advanced, more beautiful and purer soul is generated. in other words, death is the sublimation of one’s soul in poe’s mind. poe thought that death was not the end of life but a transcendence and had a metaphysical meaning. he thought that soul could be separated from body, which implies that one’s soul is immortal and eternal and it will not disappear even if one dies. in his view, death is neither a natural event, nor an accident, so one can not simply regard it as the the end of life from a chronological perspective. instead, death means rebirth and transcendence of time and space. thus, death, to some extent, has a metaphysical meaning. therefore, in allen poe’s poetry, he usually expressed the desire to transcend life by the death of beauty. . . poe’s aesthetic view “supernal beauty” has always been the core concept in allen poe’s aesthetic view and the ultimate goal in his creations, as he said, “beauty is the atmosphere and the real essence of the poem.” and “i have created beauty with superlative terms, just for beauty is the criteria for all the arts and the source stimulating arts”. in his the poetic principle, he mentioned that one’s feeling of beauty was “an eternal instinct” [ ]. he thought that pleasant things, such as form, sound, smell and emotion, etc., were the concrete forms of beauty. the reason why these things are considered beautiful is that they arouse man’s instinct to pursue beauty. thus, when these forms, sounds, smells and emotions are repeated in words, they become the source of pleasure. [ ] this sort of pleasure is indeed an instinctive feeling of beauty. jiaqi yin: an analysis of “beauty of death” in edgar allen poe’s poetry however, poe’s pursuit of beauty is not just on the stage of materials or forms, but on a much higher level. the beauty he pursued throughout his lifetime is an immortal and eternal one that transcends time and space. this beauty leads to the sublimation and excitement of the soul, which is different from the emotional excitement or the satisfaction of ordinary people. poe thought that tears people had when appreciating the eternal beauty of poetry were not due to joy but unbearable sorrow. this is because the “supernal beauty” that people feel is vague and obscure. just as vico said, “we are not yet able to grasp all the sacred and maniacal pleasures in this world once and for all.” [ ] allen poe thought that it was hard for people in this particular world to feel that extreme beauty which can only be touched through death. in order to feel, explore and even capture this kind of beauty, living people can only turn to poetry or other forms of art. this idea is clearly manifested in poe’s poetry where he tried to show the inner world of people and vividly described their desires and thoughts to stimulate readers’ instinct to pursue “supernal beauty”. therefore, the “supernal beauty” he sought is a beauty existing in the spiritual world. . conclusion it is the short and unfortunate life that emerges allen poe’s “death complex”, and it is those beautiful females in his life that lead to his pursuit of beauty. this sort of beauty transcends time and space, and can only be touched after death. in poe’s poetry, death does not mean the end of life, but a kind of rebirth and a sublimation of soul. besides, death helps people to find the “supernal beauty” which only exists in another world. this thesis conducts a study on different presentations and the root of “beauty of death” in poe’s poetry. not comprehensive enough though, it still provides a rough glimpse for readers to appreciate the extraordinary style of creation and unique aesthetic view of this genius poet. references [ ] j. r. hammond. an edgar allen poe companion. the macmillan press ltd., . [ ] kevin j. hayes. edgar allan poe. cambridge university press, . [ ] edgar allan poe. the philosophy of composition. macmilan publishing co. inc, . [ ] zhu zhenwu, wang erlei. the aesthetic presentations and poetic theories in allen poe’s poetry. foreign language education, . [ ] yu lei. “sidelong glance”the cognitive mechanism in edgar allan poe’s fictional aesthetics. foreign literatures, . [ ] yu lei. four aspects of edgar allen poe’s fictional aethestics. foreign literature, . [ ] zhang junru, zheng fei. the beauty of death—an analysis of allen poe’s and haizi’s view of death. college english(academic edition), . [ ] liu shijun. on the comparison of annabel and jiangchengzi. journal of xinyang agricultural college, . [ ] edgar allan poe. the complete tales and poems of edgar allan poe. random house, inc. . [ ] g. r thompson. the selected writings of edgar allan poe. new york: norton & company, . 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[ ] giambattista vico. new science. trans. zhu guangqian. anhui education press, . vlc_ _ - _bookreviews .. beauty lucy hartley what does it mean to be interested in beauty? the last decade ortwo have seen renewed attention to beauty both within our field, where economic and liberal discourses as well as discourses of science and the body have been brought to bear on established aesthetic tradi- tions, and in the humanities at large, where the aesthetic has to some extent been recuperated from charges of cultural elitism and social irrel- evance. i shall not attempt to count the ways beauty has been defined in nineteenth-century literature and culture nor to chart its manifold forms and values across the century, nor even to connect it, strategically or oth- erwise, to the present. rather, i shall attempt to outline a political inter- pretation of beauty by reflecting not just on what it meant but also for whom. in so doing, i place the stress on interest, that is, on the complex- ities of being interested in beauty amidst the social transformations of nineteenth-century britain. let me turn to raymond williams by way of registering the complex- ities of interest and, at the same time, registering appreciation for his work. williams is, characteristically, alert to the shifting historical senses of interest: it is, he notes, “a significant example of a word with special- ized legal and economic senses which, within a particular social and economic history, has been extended to a very general meaning,” and, he continues, “the now predominant sense of general curiosity or atten- tion, or having the power to attract curiosity and attention, is not clear before c .” here are the grounds of possibility for being interested in beauty. put differently, beauty might be understood in a limited sense as a marker of taste and privilege (as, for instance, in the essays of walter pater) and in an expansive sense as a means of imagining the lives of individual subjects and their roles and responsibilities in society (as, for example, in the writings of john ruskin). i do not want to overdraw the opposition between ruskin and pater but instead gesture to the terms of debate. to this end, i want to make three claims about the debate over beauty in nineteenth-century britain. first, that it arose from and spoke to a particular set of conditions including (but not limited to) state intervention into matters of art, the ascendency of the middle classes and the alienation of the working classes, and the extension of the franchise. second, that it pivoted on the distinction between self-regarding and other-regarding actions as vlc • vol. , no. / https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core critics, artists, and arts administrators directed individuals and groups to identify a position amongst conflicting understandings of interest in order to participate in the collective life of society and also recognize their own aesthetic advantage or detriment. third, that it revealed con- flicts between established political notions of nobility and class hierarchy and emerging democratic ideals of liberty, individuality, and equality. one way of thinking about the content and consequences of these claims is to borrow a statement from dean mathiowetz, a political theorist who contends that “arguments from interest . . . are claims about ‘who’ some- body is, and provocations to act in such a way that this ‘who’ is realized,” and, further, that “identity is not a backdrop to interest; rather, an appeal to the interest of an agent is an ascription to that agent of an identity against a field of possibilities.” to parse this statement, let me now offer an example of how beauty might serve as the ground for democracy as well as an instrument of social justice. it is well known that william morris championed “the democracy of art” in his lectures and socialist writings, decrying the destruction of society by the forces of industrial capitalism and advocat- ing for its reconstruction by reinvesting value in the production of beau- tiful objects. the terms by which morris explains this cause bear more than a passing resemblance to alexis de tocqueville’s opinions about the cultivation of the arts in democracy in america. morris was not impressed by received standards of art on the evidence of his admittedly rare visits to the royal academy, however. more appealing to his political and aesthetic sensibilities were the possibilities presented by free exhibi- tions in working-class districts of, say, manchester and london. take the whitechapel fine art loan exhibition: its purpose, morris explained at the easter opening in , was to show “beauty, imagination, [and] fancy” to “a set of people much in need of such instruction,” and to prove “a serious man” can dedicate his life to “expressing these qualities for the benefit of his fellows.” or take the art exhibition at new islington hall in ancoats, manchester where, in the same year, morris called on workingmen to claim their right to beauty: “the qualities of beauty and interest which have made these works the wonder of the world should be present in some way or another in your own daily work and have their influence on your home life, making it orderly, beautiful, in a word human.” morris was not alone in wanting a less impoverished and more toler- ant and inclusive understanding of beauty; at the same time, his provoca- tions to action were not devoid of exclusions since his appeal was made beauty https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core expressly and consistently to workingmen. in fact, the whitechapel fine art loan exhibition (sometimes called the st. jude’s picture exhibition) appealed to a broader constituency of women, children, and men than morris admitted. set up on the initiative of samuel and henrietta barnett and inspired by their commitment to ruskin’s teachings on art and society, the exhibitions, which ran from to , represent a prac- tical endeavor to democratize beauty. “what do the people want with fine art? . . . show them an oleograph of ‘little red riding hood,’ or a colored illustration of ‘daniel in the lion’s den,’ and they will like it just as much as mr. millais’s ‘chill october’ or mr. watts’s ‘love and death.’” such were some of the opinions henrietta barnett recorded about the very idea of “having an art exhibition in whitechapel.” and yet, the barnetts persisted in their belief that objects of beauty could offer a moral and cultural coun- terweight to the problem of poverty. the intersection of contemporary art with social impoverishment at st. jude’s reveals tensions between tradition and progress, between class hierarchy and property, between sacred and secular, and between aesthetic and economic conditions. these tensions are, i propose, fundamental to understanding beauty in nineteenth- century britain. notes . raymond williams, keywords: a vocabulary of culture and society (new york: oxford university press, ), , . for a related account of interest, see albert o. hirschman, “the concept of interest: from euphemism to tautology,” in rival views of market society (new york: viking penguin, ), – . . for detailed explanation of these claims, see my book: democratising beauty in nineteenth-century britain: art and the politics of public life (cambridge: cambridge university press, ), – . . dean mathiowetz, appeals to interest: language, contestation, and the shaping of political agency (university park: pennsylvania state university press, ), – . . see, in particular, william morris, “art under plutocracy,” in the collected works of william morris, with introductions by his daughter may morris. volume xxiii: signs of change. lectures on socialism (london: longmans, green & co., ), – . . alexis de tocqueville, “of the spirit in which the americans cultivate the arts,” in democracy in america, trans. henry reeve, new ed., vols. (london: longmans, green and co., ), : – . vlc • vol. , no. / https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core . may morris, william morris. artist writer socialist. volume the second (oxford: basil blackwell, ), . . morris, william morris, . . on the exhibitions, see seth koven, “the whitechapel picture exhibitions and the politics of seeing,” in museum culture: histories, discourses, spectacles, ed. daniel j. sherman and irit rogoff (minneapolis: university of minnesota press, ), – ; and diana maltz, “in ample halls adorned with mysterious things aesthetic: toynbee hall as aesthetic haven,” in british aestheticism and the urban working classes, – . beauty for the people (basingstoke: palgrave macmillan, ), – . . henrietta barnett, “pictures for the people,” in practicable socialism: essays on social reform, nd ed. (london: longmans, green & co., ), . boy matthew kaiser though she called me ‘boy’ so often, and with a carelessness that was far from complimentary, she was of about my own age. —charles dickens, great expectations beye; boye; boie; boi. it is unclear why the voiced bilabial stop knownas the “b” sound, when harnessed to the business end of the dip- thong “oi,” should appeal to the medieval ear as a means of communicat- ing diminutive or low status in male persons. what is clear, however, is that, by the early thirteenth century, the slang term “boye,” introduced to england by dutch sailors and frisian merchants, and watered liberally by tavern badinage, had taken root in english. by the time edward i expelled the jews in and conquered wales, the monosyllable had experienced a lexical growth spurt, acquiring three related but distinct meanings: male child; knave; and male servant or slave. “boy” as “knave” (the dubious, illegitimate or base man) barely survived the four- teenth century, petering out in the fifteenth, but “boy” as “male child” (the proto-man, the not-yet man, the unformed or half-grown man) beauty, boy https://www.cambridge.org/core/terms. https://doi.org/ . /s x downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s x https://www.cambridge.org/core beauty notes boy strength, functionality and beauty of university buildings in earthquake-prone countries | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /pjab. . corpus id: strength, functionality and beauty of university buildings in earthquake-prone countries @article{wada strengthfa, title={strength, functionality and beauty of university buildings in earthquake-prone countries}, author={a. wada}, journal={proceedings of the japan academy. series b, physical and biological sciences}, year={ }, volume={ }, pages={ - } } a. wada published engineering, medicine proceedings of the japan academy. series b, physical and biological sciences strength, functionality and beauty are the three qualities identifying well-designed architecture. for buildings in earthquake-prone countries such as japan, emphasis on seismic safety frequently leads to the sacrifice of functionality and beauty. therefore, it is important to develop new structural technologies that can ensure the seismic performance of a building without hampering the pursuit of functionality and beauty. the moment-resisting frame structures widely used for buildings in japan… expand view on pubmed jstage.jst.go.jp save to library create alert cite launch research feed share this paper citations view all figures and topics from this paper figure figure figure figure figure figure figure figure figure figure figure figure figure figure figure view all figures & tables walls of a building earthquakes one citation citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency energy-efficient and renewable energy-supported buildings in hot and humid regions n. enteria, h. yoshino environmental science save alert research feed references showing - of references sort byrelevance most influenced papers recency lessons from the behavior of a monitored -story building during the tohoku earthquake for robustness against design uncertainties z. qu, h. sakata, s. midorikawa, a. wada engineering pdf save alert research feed pin‐supported walls for enhancing the seismic performance of building structures z. qu, a. wada, s. motoyui, h. sakata, s. kishiki engineering pdf save alert research feed seismic collapse resistance of rc frame structures——case studies on seismic damages of several rc frame structures under extreme ground motion in wenchuan earthquake l. yi engineering save alert research feed outline of earthquake provisions in the recently revised japanese building code h. aoyama pdf save alert research feed seismic retrofit using rocking walls and steel dampers a. wada, z. qu, h. ito, s. motoyui, h. sakata, kazuhiko kasai engineering save alert research feed effect of gravity columns on mitigation of drift concentration for braced frames x. ji, m. kato, t. wang, t. hitaka, m. nakashima engineering save alert research feed seismic design of reinforced concrete and masonry buildings b. pfeffer engineering save alert research feed effect of column stiffness on braced frame seismic behavior g. macrae, yoshihiro kimura, c. roeder engineering pdf save alert research feed a more rational approach to capacity design of seismic moment frame columns k. bondy engineering save alert research feed strongback steel-braced frames for improved seismic behavior in buildings, engineering journal american institute of steel construction, ... ... related papers abstract figures and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue empirical relationships between beauty and justice: testing scarry and elaborating danto rhett diessner, lisa davis, and brett toney lewis-clark state college elaine scarry ( ) proposes a correspondence between engagement with beauty and a sense of justice. parallel to scarry, arthur danto ( ) posits that th century artists avoided producing beautiful works because of an offended sense of justice. in study , the relationship between justice reasoning (dit ; rest et al., a) and engagement with beauty (diessner et al., ) is examined; there is a significant raw correlation (r � . ; p � . ; n � ), which reduced to a nonsignificant r � . when openness to experience was partialed out. study examines the relationship between fairness as a character strength (cf. peterson & seligman, ) and engagement with beauty, finding a raw r � . , p � . (n � ). after partialing out openness to experience the r is . , significant at p � . . although there is no significant association between justice reasoning and engagement with beauty, when justice/fairness is viewed as a character strength, scarry’s hypothesis is empirically validated. thus, justice-minded artists need not avoid beauty, as beautiful art may increase viewers’ sensitivity to justice. keywords: beauty, justice, dit, character strengths, trait fairness in elaine scarry, walter m. cabot professor of aesthetics at harvard university, offered her provocative tanner lectures on beauty and justice, at yale university, which were later published by princeton university press as, on beauty and being just (scary, ). in the first of this tiny text, entitled, “on beauty and being wrong,” scarry provides background to understand her argument concerning beauty and justice. she emphasizes how easy it is to overlook beauty in the world and to believe something is not beautiful when it is, and thus be wrong. she goes on to observe that engagement with beauty leads to a love of conviction, which in its turn leads to a love of the search for truth; and truth is a necessary condition for justice (viz., p. , p. ). the second part of her lovely little tome, which directly ad- dresses beauty and justice, is entitled, “on beauty and being fair.” her argument, which is a bit elusive (gitlin, , p. ; nehamas, ; paden, ), follows this line: we love beauty, thus we love symmetry, and thus we love justice. she invokes “justice as ‘fairness,’ using the widely accepted definition by john rawls of fairness as a “symmetry of everyone’s relations to each other’” (scarry, , p. ). scarry ( ) describes a political critique of beauty by noting that some critics contend that beauty attracts and holds our atten- tion and thus distracts us from unethical social arrangements and thus makes us indifferent to acting on social justice. she argues against this view, making the case that beauty is innocent of these charges, at the very least; rather it is likely that beauty creates a pressure within us to rectify existing injustices. scarry also con- nects beauty and justice linguistically (p. ff), by creatively exploring etymological links, across a variety of languages, of beauty as fairness (loveliness of countenance) and of justice as fairness (an ethical demand). as well, she links beauty and justice through the concept of “distribution”– beauty encourages the vol- untary extension of one’s gaze toward finding beauty distributed across our world, and this sets the conditions to be concerned with distributive justice. she goes on to argue that all three sites of beauty—the object, the perceiver, and the act of creation—all expose the pressure beauty exerts toward ethical equality. what is the quality of scarry’s arguments about the relationship between beauty and justice? although reviews of her text have been mixed (gitlin, ; paden, ), we find nehamas’ ( ) summary the most balanced and accurate. he asserts that “her book is a hymn to the love of beauty” analogous to agathon’s speech plato’s symposium as “a hymn to the beauty of love. both are fresh, eccentric, and uncompromising, and both leave you dazed—suspended between admiration and doubt, eager to praise and compelled to criticize” (p. ). we also feel admiration for and a desire to praise scarry’s thoughts on beauty and justice. as social scientists, however, we would like to postpone criticism of scarry’s ideas until we have collected and analyzed data relevant to the relationship between beauty and justice, which we do below. danto: the fall and rise of beauty dickie ( ) argues that the decline of beauty, that is, the decline of its importance to philosophers of aesthetics and to art critics, began with the th century german and british philos- ophers who, frustrated with their inability to define beauty, and their recognition of other relevant aesthetic factors (the sub- lime, the picturesque, the aesthetic attitude, etc.), removed beauty from its central position in art and aesthetics. by the th century beauty was seldom mentioned by philosophers of aesthetics, and it began to be spurned by artists as well. arthur rhett diessner, lisa davis, and brett toney, psychology department, social sciences division, lewis-clark state college. correspondence concerning this article should be addressed to rhett diessner, lewis-clark state college, th avenue, lewiston, id – . e-mail: diessner@lcsc.edu psychology of aesthetics, creativity, and the arts © american psychological association , vol. , no. , – - / /$ . doi: . /a danto, emeritus johnsonian professor of philosophy at colum- bia university, has undertaken to explain why many artists during the th century, especially those of the avant-garde, purposely avoided beauty in their creations (danto, , ). in the early th century, many socially conscious and radical artists purposefully avoided creating anything beautiful, and viewed a focus on beauty as naı̈ve and irresponsible. danto ( ; and cf. higgins, ) notes that the art of the th century is an art of activism, indignation, and accusation. he believes that modern artists perceive beauty as consoling. be- cause of their sense of justice, modern (and post modern) artists do not want to console—they want to provoke and accuse. danto notes that consolatory beauty in art is ethically inconsis- tent with the indignation necessary for accusatory art, and thus beauty had to be exiled. focusing on the late th century, scarry ( ) appears to agree, by arguing beauty has been banished from the humanities for the last two decades. yet, at the beginning of this st century, there has been a call to bring beauty out of exile and back into art (danto, )–note the symposium for philosophers and art critics, in the last year of the th century, was entitled, “beauty matters” (viz., eaton, ). eaton argues that by the end of the th century there was a trend for aesthetic theorists and artists to believe once again that beauty does matter in art. danto ( ) states that from the th to early th century it was simply presumed that art should possess beauty. he traces the downfall of beauty to the dada movement, which out of a sense of justice, objected to making anything beautiful for the pleasure of the social class that was responsible for the first world war. at the time of world war i artists were deeply unsettled by the west’s hypocrisy in believing itself to be highly civilized, yet creating and participating in the greatest carnage in history. thus, beauty became suddenly politicized by socially conscious avant- garde artists in , and abusing beauty was a way for them to dissociate themselves from a society for which they had great contempt. this trend continued through the th century–danto notes that the whitney biennial of was full of shocking works, that disturbed the viewers, but which demonstrated the commitment of american artists to addressing injustices of race, class, and gender. danto appears sympathetic to this, implying that victimization is ugly, and thus to make such works beautiful would be artistically wrong. danto is at pains to show that beauty is not necessary in a work of art; but that nonetheless, beauty is a fully appropriate goal for artists whose creative works are internally congruent with a dis- play of beauty. he describes the spontaneous appearance of im- provised shrines throughout new york after the / attack, stat- ing that this was evidence of a deeply ingrained need for beauty in human life: i came to view that in writing about beauty as a philosopher, i was addressing the deepest kind of issue there is. beauty is but one of an immense range of aesthetic qualities, and philosophical aesthetics has been paralyzed by focusing as narrowly on beauty as it has. but beauty is the only one of the aesthetic qualities that is also a virtue, like truth and goodness. it is not simply among the values we live by, but one of the values that defines what a fully human life means” (p. – ). is it necessary to avoid beauty to create a more just society? if scarry is correct in saying that experiences of beauty correspond to an increased awareness of justice, then a conscious abandonment of beauty may backfire, unintentionally leading to further injus- tices. we agree with danto, not all works of art need be beautiful; on the other hand, beauty need not be the enemy of justice. the importance of beauty in the west beauty, since the dawn of western civilization, has been one of the three ends of human being: truth, beauty, and the good (plato, / ). of course, in our post modern age, the words and concepts of truth, beauty, or the good have been kicked off the pedestal of divine forms and deconstructed, whereas many intel- lectuals assume they remain in usage only among the naı̈ve. nonetheless, whether one believes truth, beauty and the good to be objective realities, or simply concepts used to gain power and oppress others, they continue to provoke and organize the thought of scholars, artists, and laypersons. in addition, close on the heels of these three big ends is the concept of justice. justice is the prominent moral principle of plato’s republic—socrates argues justice is the central principle for structuring the order of a city- state, as well as organizing the individual human psyche (diessner, frost, & smith, ). many of the west’s most influential philosophers have argued for the fundamental importance of beauty: thomas aquinas ( / ; see eco, ), aristotle (ca. bce/ ), augustine ( / ); dewey ( / ), ficino ( / ), ( / ), kant ( / ), plotinus, / , santayana ( / ), and schopenhauer ( / ). philosophers have ad- dressed both beauty in art and beauty in nature (beardsley, ; croce, / ; hofstadter & kuhns, ; mothersill, ; sheppard, ). moral beauty (cf. haidt, , , , ; haidt & keltner, ; keltner & haidt, ), in the context of the beauty of human virtue has been emphasized by aristotle. aristotle ( ) argued that the end (the goal) of all virtues is beauty. danto ( ) briefly refers to moral beauty as well (p. ). the importance of beauty across cultures in beauty happily i walk. with beauty before me i walk. with beauty behind me i walk. with beauty below me i walk. with beauty above me i walk. with beauty all around me i walk. (navajo/diné prayer; quoted in jones, , p. ) it appears that every culture has standards of beauty; beauty is a universal value (haidt & keltner, ; washburn, ). there are at least two broadly influential sources for the importance of beauty across cultures. one is our evolutionary past: perceiving aspects of nature as beautiful appears to have adaptive or survival value (averill, stanat, & more, ; etcoff, ; richards, ). another source can be found in the spiritual traditions and religions of humankind. spirituality and religion have influenced beauty in art from ancient through modern times (cf. mark tobey in dahl, ; kandinsky, / ). the concept of beauty is diessner, davis, and toney ubiquitous in the sacred texts of the world’s religions, commonly embedded in the concept of glory. “great beauty” is a direct synonym of “glory” (gove, , p. ). reference to beauty and glory are found in the hindu bhagavad-gita (arjuna & krishna, ca. bce/ ); in the psalms (king david, ca. bce/n.d.) of judaism; in the buddhist dhammapada (buddha, ca. bce/ ); in the christian bible (john, : , kjv, ca. ce/n.d.); in islam’s qur’án (muhammad, ca. ce/ ); and in the bahá’ı́ writings (bahá’u’lláh, / ). assessing appreciation of and engagement with beauty there is very little empirical work indexed by psycinfo, eric, or socindex on engagement with beauty, other than a wide variety of studies on issues of human physical/cosmetic beauty. one exception is milton rokeach’s ( ) and his colleagues (cf. mayton, ) work on human values. rokeach framed a world of beauty as a human terminal value, and found that americans considered it to be among the least important of values in the late s and early s. this finding by rokeach parallels danto’s ( ) and scarry’s ( ) concerns about the lack of interest in beauty in philosophy and the humanities in the th century. humanistic and existential psychologists have addressed the im- portance of beauty, but typically without a systematically empir- ical focus (maslow, , ; may, ). empirically oriented personality psychologists costa and mccrae ( ), creators of the neo-pi scale which measures the five factor model of personality, have framed openness to aes- thetics as a specific trait within the broader trait of openness to experience. their openness to aesthetics facet scale measures appreciation for beauty in art. research using this facet scale has established a wide variety of findings (brown, wise, & costa, ; griffin, & mcdermott, ; lusebrink, ; mccrae, ; perrine, & brodersen, ; thompson, brossart, & car- lozzi, ). studies using the engagement with beauty scale (ebs; diess- ner, parsons, solom, frost, & davidson, ), which has three subscales measuring engagement with natural beauty, artistic beauty and moral beauty, have shown that engagement with beauty has medium to high positive correlations with the traits of gratitude and spiritual transcendence and a low negative correlation with endorsement of materialistic values. a known-groups study dem- onstrated that the ebs artistic beauty subscale differentiated college students taking courses in the arts from those that were not. in a beauty intervention study (diessner, rust, solom, frost, & parsons, ), it was shown that college students who partici- pated in focused engagement with beauty exercises significantly increased their level of engagement with beauty. that study also demonstrated that engagement with beauty is significantly corre- lated with the trait of hope. cattron’s ( ) study with the ebs found that engagement with beauty significantly correlates with mindfulness (a height- ened state of being in the present) (n � ; r � . total score, p � . ). he also showed that engagement with artistic beauty correlates higher with mindfulness (r � . , p � . ), than do engagement with natural beauty (r � . , p � . ) or moral beauty (r � . , p � . ). international studies (richel et al., ; susnjic & diessner, ) using translations of the ebs in iran, samoa, germany, cyprus, and croatia, have shown it to maintain fairly high internal consistency across translations (�s for total score from . –. ). such high alphas indicate that engagement with natural beauty (�s from . –. ), with artistic beauty (�s from . –. ), and with moral beauty (�s from . –. ), are coherent and meaningful concepts in cultures from europe, the mediterranean, the middle east, and the south pacific. in the context of the positive psychology movement, peterson and seligman ( ) have developed the item values in action inventory of strengths (via-is), which provides a ranking of character strengths. one such strength is labeled “apprecia- tion of beauty and excellence,” and it is measured by a -item subscale of the via-is. a study by peterson, park, and seligman ( ) shows that appreciation of beauty may be one of the most important and effective character strengths involved in gaining satisfaction with life after overcoming depression and other psy- chological disorders. riddle and michel-riddle ( ) used the via-is to study a small sample (n � ) of male art therapists and art therapy students (they selected men as an unusual group, as the field is apparently % women). they found that the two highest ranked character strengths for this sample, of the strengths measured on the via-is, were “curiosity and interest in the world” and “appreciation of beauty and excellence.” on a biological note, steger, hicks, kashdan, krueger, and bouchard ( ), in a study using the via-is with n � twins, found that monozygotic twins showed a correlation of . with the appreciation of beauty and excellence subscale, but dizygotics had a correlation of . . such correlations were typical across all via-is character strengths, indicating levels of heritability that are characteristic for most personality traits. assessing a sense of justice psychologists have approached assessment of the human sense of justice primarily in two ways. one method has been to assess the ability to think and reason about justice, pioneered by piaget, and elaborated extensively by kohlberg ( ; colby & kohlberg, ; and cf. gibbs et al., ) and rest ( ; rest, narvaez, bebeau, & thoma, b). the other approach is to view justice as a personality trait or as the character strength of fairness (peterson & seligman, ; lee & ashton, , ). kohlberg ( ), following the lead of piaget, defined a six stage structural model of the development of the ability to reason with justice. in kohlberg’s methodology (colby & kohlberg, ), interviewers present moral dilemmas to subjects and ask them their solutions; their responses are recorded, transcribed and scored for stage level. james rest ( ) developed a multiple choice format for assessing justice reasoning, the defining issues test (dit), which is based on kohlberg’s theory and presents subjects with moral dilemmas similar to the ones that kohlberg used. the subjects read the dilemmas, and then mark their pre- ferred choice of solutions. the choice of options, following the dilemmas on the dit, represent kohlberg’s stages, and thus pro- vide the researcher with a percentage score of how often the subjects selected principled level choices. with both kohlberg’s and rest’s approaches the individual’s level of justice reasoning is determined. there is a large empirical track record, as well as theoretical arguments, concerning the relevance and meaningful- ness of their research programs (kohlberg, , ; rest et al., b). beauty and justice the personality approach to assessing a sense of justice views justice as the trait of fairness. the trait of fairness includes such attributes as being committed to fairness in social relations, being sensitized to issues of social and distributive justice, being trust- worthy, being civic minded, honoring one’s promises, not cheat- ing, not stealing, following rules, and believing in equality and equity. the values in action inventory of strengths (via-is; peterson & seligman, ) measures such a trait, which they call the character strength of fairness or equity. likewise, lee and ashton ( , ) have developed a facet scale which they named justice, as one of the personality facets measured by their hexaco personality inventory (hexaco-pi). purpose of the present studies the main purpose of the two studies reported below is to examine whether or not there is empirical support for scarry’s argument that beauty and justice are related. study will examine whether there is a significant positive relationship between en- gagement with beauty and justice reasoning. study will examine whether there is a significant positive relationship between en- gagement with beauty and the character strength of fairness. this appears to be fresh empirical territory—the psycinfo, eric, and socindex databases reveal no published empirical studies concerning the relationship between engagement with beauty and justice, other than related to issues of human physical/ cosmetic beauty. for instance, forbes, collinsworth, jobe, braun, and wise ( ) found that oppression/injustice and hostility toward women correlated with endorsement of western physical beauty ideals; and callan, powell, and ellard ( ) showed that participants judged the accidental death of an attractive woman as more tragic and unfair than the death of a less attractive woman (they also reviewed research relevant to injustice and beauty, such as physically attractive individuals being perceived as more qual- ified to obtain jobs, getting better health care services, receiving more lenient criminal sentences, and being offered help more often). however, it appears there are no published studies exam- ining engagement with beauty in general (such as natural beauty, artistic beauty, or moral beauty) and its relationship to either justice reasoning or to the character strength of fairness. the two studies below remedy those lacunae. study : engagement with beauty and justice reasoning the introduction to this study is contained in the above general introductory section. method participants the participants were a convenience sample of n � under- graduates at lewis-clark state college, in lewiston, idaho, re- cruited in fall, from introductory, developmental and edu- cational psychology classes. there was wide diversity of majors in those classes: % teacher education, % social science, % natural science, % humanities, % vo-tech, % undecided, and % nonreporting. the participants had a mean age of . (sd � . ; range – ); were % women; % african, % asian, % euro, % latino, % marked “mixed,” and % native american. measures engagement with beauty scale. the ebs is a -item self- report scale describing various levels of cognitive and emotional engagement concerning natural, artistic, and moral beauty. al- though there are other instruments that measure appreciation of beauty as a subscale, the ebs is the only scale extant that is devoted to measuring the trait of engagement with beauty. the ebs uses a -point likert scale ranging from “very unlike me” to “very much like me,” on questions such as, “when per- ceiving beauty in nature i feel changes in my body, such as a lump in my throat, an expansion in my chest, faster heartbeat, or other bodily responses,” “when perceiving beauty in a work of art i feel something like a spiritual experience, perhaps a sense of oneness or being united with the universe or a love of the entire world,” and “when perceiving an act of moral beauty i find that i desire to become a better person” (diessner et al., ). the ebs provides a total scale score and also has three sub- scales tapping engagement with natural beauty (four items), artistic beauty (four items), and moral beauty (six items). studies of the ebs with an american sample (n � ; % female) yielded a total score internal consistency of . , and test–retest reliability of . ; ebs natural beauty subscale � of . ; artistic beauty sub- scale � from . ; and the ebs moral beauty subscale � from . ; test–retest reliability correlations ranged from . to . on the subscales. factor analytic studies (efa and cfa) and goodness of fit indices show the three subscales reasonably fit a -factor model (diessner et al., ). international studies with translations of the ebs, in iran, samoa, germany, cyprus, and croatia, have shown it to maintain fairly high internal consistency across translations (�s from . –. ) and to have a similar factor structure across cultures (richel et al., ; susnjic & diessner, ). a variety of concurrent and predictive studies have shown the promising validity of the ebs (diessner et al., , ). in this current study the ebs total score had a cronbach’s alpha of . ; the natural beauty subscale’s was . ; artistic beauty . ; and the moral beauty subscale’s alpha was . . defining issues test- . the revised defining issues test (dit ; bebeau & thoma, ) is a shortened, revised, and improved version of the original dit (rest, ). both the dit and dit consist of several moral dilemmas, each of which is followed by multiple-choice questions that are keyed to kohl- berg’s ( ) stages of justice reasoning. the results of the dit produces a p-score, which is a percentage of items ranked as highly important by the participant, that are at the principled (postconventional) level of justice reasoning. the dit offers a new score, the n , which integrates the subject’s p-score with the degree to which the subject rated lower stage items (personal interest items) below higher justice reasoning stage postconven- tional items. both the dit and dit have a wide range of validity indices (rest, narvaez, thoma, & bebeau, a; rest et al., b). the dit has shown moderate internal consistency, with a cronbach’s alpha ranging from . (crowson & debacker, ) to . (rest et al., a), for the n score. in our current study the alpha, for the n � valid n scores, was . . diessner, davis, and toney neo-pi-r. the neo-pi-r (neo personality inventory– revised), self-report form s (costa & mccrae, ) is a classic measure in personality assessment, providing scores for each of the domains of the five-factor model theory of personality: neuroti- cism, extraversion, openness to experience, agreeableness, and conscientiousness. these domain scores show internal consis- tency coefficients from . to . . multiyear test–retest reliability coefficients are in the range of . to . ; each domain has a variety of facet scales within them, with internal consistency coefficients ranging from . to . . costa and mccrae report a variety of validity studies relating the neo-pi-r to other person- ality inventories and projective measures. for the domain that is of interest in our current study, openness to experience, costa and mccrae report an alpha of . , and for the aesthetic facet scale a . . in our current study, the openness to experience scale had an alpha of . , and the aesthetic facet scale’s alpha was . . procedure half the subjects completed the ebs first, the other half the dit first, to avoid sequencing effects. a week after taking the ebs and dit , n � of these same subjects completed the neo-pi-r (costa & mccrae, ). the participants were given course credit to complete the scales; the study was approved by the lcsc human subjects committee, and all apa ethical research standards were adhered to. design of statistical analysis the two main variables under study, engagement with beauty as shown by total score on the ebs, and justice reasoning as shown by n score of the dit , will be correlated using a pearson product–moment correlation. as the trait of openness is known to influence both appreciation of beauty, and justice reasoning, a partial correlation will be computed, controlling for openness to experience, as measured by the neo-pi. results ebs total score showed an r � . ( p � . ) with the dit n score; additionally, the dit n score correlated with the ebs natural beauty subscale, r � . ( p � . ), with the ebs artistic beauty subscale, r � . ( p � . ), and with the ebs moral beauty subscale, r � . (n.s.). however, after partialing out the openness to experience factor of the neo-pi-r (n � ) the correlation dropped to a nonsignificant r � . . as a psychometric aside, the ebs total score showed a . correlation with the aesthetic facet scale of the neo-pi-r (costa & mccrae, ); and the ebs natural beauty subscale correlated . , the ebs artistic beauty subscale . , and the ebs moral beauty subscale . with the aesthetics facet. discussion initially it appeared that scarry’s hypothesis was somewhat vindicated by the positive and significant, though small, correla- tion between engagement with beauty and justice reasoning. how- ever, the major trait, openness to experience is known to correlate with the endorsement of both appreciation of beauty and justice/ equality; for example, political liberals score much higher on openness scales, and endorse appreciation of beauty and equality, much more than political conservatives (viz., haidt, ; haidt & graham, ). therefore, it was deemed important to examine if there was any relationship between beauty and justice reasoning after partialing out the influence of openness to experience. after partialing out openness, the correlation between engagement with beauty and justice reasoning dropped to . , which is essentially no relationship at all. so, was scarry wrong? the dit specifi- cally measures the ability to reason, in the kohlbergian tradition, about justice-oriented issues. perhaps, rather than reasoning abil- ity, scarry’s hypothesis is relevant to personality, to the trait of being fair, of being oriented to and cherishing justice. we decided to further test her hypothesis by examining the relationship be- tween engagement with beauty and fairness as a character strength. below, in study , we do just that. we expected that the dit , a measure of moral/justice reason- ing, would correlate higher with the ebs subscale of moral beauty engagement, than with the ebs’s artistic or natural beauty sub- scales. however, this was not the case—there was no significant relationship between moral/justice reasoning and engagement with moral beauty; but there were significant correlations between justice reasoning and engagement with both artistic beauty and with natural beauty. could it be that persons with a high level of justice reasoning tend not to look for the inner beauty in others, but they do seek beauty in art and nature? future research on this topic appears warranted. in the original technical paper on the ebs (diessner et al., ), concurrent validity between the neo-pi-r aesthetic facet scale (costa & mccrae, ) and the ebs was not reported. our data in this study show a correlation of . between the ebs total score and the aesthetics facet scale; this correlation is high enough to indicate that the two scales may be measuring something quite similar, but low enough to show they are not measuring something identical. as the neo-pi-r aesthetic facet scale has eight items, of which . refer to art [music, dance, poetry, art], and half of a question refers to patterns in nature, and has no item concerning moral beauty, it is not surprising that the ebs engagement with art subscale correlates higher with the aesthetic facet (r � . ) than do the natural beauty (r � . ) or moral beauty (r � . ) subscales of the ebs. study : engagement with beauty and the trait of fairness there appear to be no published studies which examine the empirical relationship between measures of engagement with beauty and the trait (or character strength) of fairness. we predict a moderately high correlation between the ebs and the ipip-via fairness scale. to address discriminant validity, we will correlate two character strengths that we anticipate would have low, non- significant, correlations with the ebs–the ipip-via modesty/ humility scale and the ipip-via industry/perseverance/ persistence scale. see the above general introductory section for background to this study. method participants the participants were a convenience sample of n � under- graduates at lewis-clark state college, in lewiston, idaho, re- beauty and justice cruited from spring, introductory, developmental and edu- cational psychology classes. there was wide diversity of majors in those classes: % teacher education, . % social sciences, . % natural sciences, % humanities, . % vo-tech, . % undecided, and . % left it blank. the participants had a mean age of . (sd � . ; range – ); and are % women; . % asian, . % euro, . % latino, . % marked “mixed,” . % native american, . % other, and . % no response. measures engagement with beauty scale. see above, in study , for a description of this scale. in this study , the ebs showed cron- bach’s alphas of . for total score; . for the natural beauty subscale; . for the artistic beauty subscale; and . for the moral beauty subscale. defining issues test- . see above, in study , for a description of this test. in this current sample, with an n � , the cronbach’s alpha was . . ipip-ffm-openness to experience scale. rather than use the expensive neo-pi-r, to get results for a single domain scale (openness to experience), we used the international personality item pool, five factor model, item openness to experience scale (goldberg, ; goldberg et al., ; http://ipip.ori.org/). saucier and goldberg ( ) report, with an n � from a community sample, a corrected correlation of . between the -item openness scale of the ipip ffm measure and the neo- pi-r openness domain scale. they also report a coefficient alpha of . for this openness scale, and in our current study, we found an alpha of . . ipip-via fairness scale. this is a -item, likert response, free-use scale from the ipip site (goldberg et al., ; http:// ipip.ori.org/) that measures the trait-like character strength of “fair- ness” or equity, and has a reported cronbach’s alpha of . . in the study reported here, the scale had an alpha of . . the ipip-via fairness scale is an analogue scale of the fairness/equity subscale of peterson and seligman’s ( ) values in action scale (via). the ipip-via fairness scale and the original via fairness scale contain items similar to, “i am committed to principles of justice and equality,” “i treat all people equally,” and “i believe that everyone should have a say.” peterson and seligman ( ) define the character strength of fairness by referring to an “individual’s treatment of other people in similar and identical ways—not letting one’s personal feelings or issues bias decisions about others,” and can refer to either a “radical equality of treatment or a more nuanced equity of treatment” (p. ). ipip-via modesty/humility scale. this is a -item, likert re- sponse, free-use scale from the ipip site (goldberg et al., ; http://ipip.ori.org/) that measures the trait-like character strength of modesty and humility, and has a reported cronbach’s alpha of . . in the study reported here, the scale had an alpha of . . the ipip-via modesty/humility scale is an analogue scale of the modesty/humility subscale of peterson and seligman’s ( ) values in action scale (via). although there is little empirical validity evidence published concerning this specific subscale, a variety of studies are showing the via’s promising validity (park, peterson, & seligman, , ; peterson, park, & seligman, ). ipip-via industry/perseverance/persistence scale. this is an -item, likert response, free-use scale from the ipip site (gold- berg et al., ; http://ipip.ori.org/) that measures the trait-like character strength of industry, perseverance, and persistence, and has a reported cronbach’s alpha of . . in the study reported here, the scale had an alpha of . . the ipip-via industry/perseverance/ persistence scale is an analogue scale of the industry/perseverance/ persistence subscale of peterson and seligman’s ( ) values in action scale (via). although there is little empirical validity evidence published concerning this specific subscale, a variety of studies are showing the via’s promising validity (park, peterson, & seligman, , ; peterson, park, & seligman, ). procedure the ebs, ipip-via fairness scale, ipip-openness to experi- ence scale, and a political affiliation measure (which will not be reported on in this study) were randomly ordered into packets (to prevent any sequencing effect) and completed by the participants during class time. a subset of n � then completed the dit two weeks later. four weeks after that n � of the original subjects completed the ipip-via modesty/humility scale and the ipip-via industry/perseverance/persistence scale; half the sub- jects completed the modesty scale first, the other half the industry scale, to prevent sequencing effects. the participants were given course credit to complete the scales; the study was approved by the lcsc human subjects committee, and all apa ethical research standards were adhered to. design of statistical analysis the two main variables in study , engagement with beauty as shown by total score on the ebs, and the character strength of fairness, as measured by the ipip-via fairness scale, will be correlated using a pearson product–moment correlation. as the trait of openness is known to influence both appreciation of beauty, and endorsement of justice, a partial correlation will be computed, controlling for openness to experience. to examine whether a positive response style could account for finding a relationship between engagement with beauty and the character strength of fairness (i.e., someone who indiscriminately endorses any and all character strengths), we will correlate two other character strengths—modesty/humility and industry/perseverance—with the ebs, as measured by the ipip-via modesty/humility and the ipip-via industry/perseverance/persistence scales. results the correlation between the ebs total score and the ipip-via fairness scale was r � . , p � . (n � ); after partialing out openness to experience the r dropped to . , but was still signif- icant at p � . . the three ebs subscales all showed significant correlations with the ipip-iva fairness scale: natural beauty r � . ( p � . ); artistic beauty r � . ( p � . ); moral beauty r � . ( p � . ). however, after partialing out openness to experience, only the engagement with natural beauty subscale retained statistical significance: natural beauty r � . ( p � . ); artistic beauty r � . ( p � . ); moral beauty r � . ( p � . ). diessner, davis, and toney the ebs total score showed a statistically nonsignificant r of . ( p � . ; n � ) with the ipip-via modesty/humility scale; and likewise with the ipip-via industry/perseverance/persistence scale, r � . ( p � . ; n � ). the correlation between the dit n score and the ebs, for an n � subsample, was . ( p � . ); but after partialing out openness to experience, the r dropped to a statistically nonsignif- icant . ( p � . ). the correlation between the dit n score and the ipip-via fairness scale was a nonsignificant . ( p � . ). discussion of study scarry ( ) may be right. if her hypothesis about the connec- tion between beauty and justice is referring to the personality trait of being fair, then these data support her argument. the . correlation between the ebs and the ipip-via fairness scale is medium-sized and significant; and even after partialing out the openness factor, the relatively small correlation of . remains significant ( p � . ). thus, there does appear to be a small relationship between engagement with beauty and the character strength of fairness. although the correlation between justice reasoning, as measured by the dit , and engagement with beauty, was higher in study than study (. vs. . ), after partialing out the broad trait of openness to experience, it was not statistically significant. there- fore, we tentatively conclude that justice reasoning and engage- ment with beauty are unrelated. to be confident that people scoring high on the ebs are not simply positive people in general, who tend to endorse character strengths in general, we also ad- ministered to ipip-via subscales that measure modesty/humility and industry/perseverance. we hypothesized that these two traits are unrelated to engagement with beauty, and the data supports that; both had very low nonsignificant correlations with the ebs total score. this indicates that those scoring high on engagement with beauty do not indiscriminately score high across a range of desirable character strengths. it adds discriminant validity to the claim that fairness as a character strength has a meaningful rela- tionship with engagement with beauty. general discussion what is the difference between justice reasoning and the per- sonality trait of fairness? justice reasoning, as measured by kohl- berg ( ) and rest ( ), has its roots in jean piaget’s para- digmatic approach to psychology. this approach, typically called cognitive-development in english language textbooks, was re- ferred to by piaget as genetic epistemology. the emphasis in justice reasoning is upon cognition, logic, and reason. traits, however, are not focused on our reasoning ability, but rather are dispositions to feel and to act. a trait is a way of being. the ability to reason and the disposition to feel and act are two different things. on the other hand, we believe in a unified psyche, in which the fundamental abilities to think, emote and will, are in constant dynamic interaction, and are inseparable (diessner, ; diessner et al., ). nonetheless, reasoning can be differentiated from feelings and action. traits are ontologically closer to the core of human being than is thinking or reasoning. heidegger trumped descartes in arguing that ontology must precede epistemology— existence is logically before thinking. the major finding in the two studies presented here is that engagement with beauty is signifi- cantly related to the trait of fairness, but not related to justice reasoning. engagement with beauty appears more closely related to emotions, feelings, and patterns of behavior, than it is to reasoning. therefore, to the degree that elaine scarry views justice as the trait of fairness more than as an ability to reason about fairness, the data in these studies support her argument. she does appear to view justice as something like a trait, as she emphasizes motivation toward justice, and specifically that engagement with beauty leads to “attention to justice” ( , p. ). again, we are not encouraging an artificial separation between thinking and feeling, or between reasoning and traits, no doubt they interpene- trate in vivo. sherblom ( ) must think so, as he emphasizes the moral reasoning aspect of the character strength of fairness. these studies have important implications concerning the role of beauty for st century artists. as danto ( ) has described, western artists, especially the avant-garde, spurned beauty based on their own notions of justice. the artists reasoned (or felt or intuited) that purposefully producing works of beauty was to cater to a bourgeois class that was destroying our world both socially and materially, and to offer beauty to the public was placating forces of evil. producing works that shocked and confused was a form of justice-activism among artists. danto concludes, however, that beauty still has its place; he makes it clear that art can be created that is not beautiful and still have artistic merit. however, he also emphasizes that the goal of beauty in a work of art is perfectly acceptable, and not necessarily socially irresponsible on the part of the artist. the findings in our studies here—that engagement with beauty and fairness as a personality trait are significantly correlated— implies that when artists create works of beauty they may be enhancing the viewing public’s development of the trait of fair- ness, especially when that beauty is internally appropriate to the subject matter of the painting (viz., danto, chapter , “internal and external beauty,” ). there certainly is ugliness in injustice, and thus danto would support the idea that when painting about issues of injustice, it is perfectly appropriate to paint a nonbeautiful painting. on the other hand, danto would also agree that a wide range of issues can be appropriately portrayed with beauty without artists compromising their integrity or setting aside their social consciousness. danto uses the vietnam war memorial, designed by maya lin, as an example—the memorial is about “healing,” and the beauty that is internal to it supports that meaning. that beauty and justice go hand-in-hand indicates that an art education that encourages the creation of beauty does not work against creating a sense of justice in art students. in fact, it implies that art teachers who emphasize the creation of beauty in works of art may actually be setting the conditions for their students to further develop their sense of justice, fairness, and equality. it also implies that observers of beauty in art (as well as observers of natural beauty, and human inner beauty) will have their character strength of fairness reinforced and encouraged. we are not stating that simply increasing one’s engagement with beauty is sufficient to create justice–howard gardner ( ) has pointed out that the nazis valued beautiful works of art, but nonetheless were one of the worst perpetrators of injustice in the history of our planet. however, as it seems likely that most events, processes, and occurrences are multicausal, beauty may at least be one of the beauty and justice forces of the universe that move us toward social justice and intra- and interpersonal fairness. the studies reported here are simple correlational studies; they are preliminary studies examining whether there is any empirical support for scarry’s argument that engagement with beauty is related to the disposition to act justly. future experimental designs that could determine causality (does beauty cause justice, or justice cause beauty?), or structural equation modeling to examine causal pathways, are warranted. science, including psychological social science, requires replication, and the external validity of the find- ings in the studies reported here would be enhanced by studying participants in a wider range of ethnic and geographical diversity. we will end this paper with the end of danto’s abuse of beauty ( ); the last three sentences of that book are: beauty is an option for art and not a necessary condition. but it is not an option for life. it is a necessary condition for life as we would want to live it. that is why beauty, unlike the other aesthetic qualities, the sublime included, is a value (p. ). references aquinas, t. 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( ). aesthetic universals in cultural perception and practice. in p. locher, c. martindale, & l. dorfman, (eds.), new directions in aesthetics, creativity, and the arts (pp. – ). amityville, ny: baywood pub. co. received september , revision received november , accepted november , � diessner, davis, and toney crowdsourcing architectural beauty online appendix for the paper “crowdsourcing architectural beauty: online photo frequency predicts building aesthetic ratings.” albert saiz∗ arianna salazar† james bernard‡ this section contains supplementary material for the paper “crowdsourcing ar- chitectural beauty: online photo frequency predicts building aesthetic ratings.” section a discusses the differences between panoramio and flickr. section a presents additional figures to illustrate the variation of image uploads. section a shows additional robustness tests that validate the use of image uploads as a proxy for building beauty. finally, in section a we include a subset of the photos shown to the survey respondents (including their ranking) and a copy of the survey instru- ment. a panoramio, flickr, and image uploads as probability fields: potential pitfalls, promises, and solutions both panoramio and flickr are examples of volunteered geographic information (vgi) by internet users active on their websites (f. goodchild ( )). therefore, we expect a degree of error in the measurement of the latitude and longitude in user- contributed geotagged photos. many of these images contain precise coordinates ∗ urban studies and planning department, massachusetts institute of technology, e-mail:saiz@mit.edu † urban studies and planning department, massachusetts institute of technology, e-mail: ariana@mit.edu ‡ economics department, brown university, e-mail: jamesbernard@brown.edu a from the exchangeable image file format (exif) used by cameras and smartphones with gps systems. these coordinates capture the position from which the photo was taken. however, both panoramio and flickr allow users to pin down image locations on a digital map, absent exif information. in both sources the pinning down of images to the position from which they were taken is encouraged by software, but users may be using alternative heuristics for photo location (et al. larson ( )). nevertheless, since city street widths limit the distance between the position of the author and the landmark, we can expect for photos taken and uploaded around major urban buildings to have geotags that are proximate to the building’s coordinates. moreover, users taking photos at far distances from a building tend to geotag the objective. recent research by zielstra and hochmair ( ) has carefully analyzed the posi- tional accuracy of images in flickr and panoramio. these authors find panoramio’s geotags to be more accurate than flickr’s since its users are more likely to own bet- ter cameras and to be more sophisticated in geolocating their photos. importantly, a large number of discrepancies are due to users geotagging the exact coordinates of the buildings they were capturing, not the point of where they were shooting ( and percent for north american street buildings in flickr and panoramio, respec- tively). therefore, positional errors are generally biased in the direction of making photo geotags closer to the target buildings. moreover, differences between flickr and panoramio can be attributed to the type of photo that is being posted. for ex- ample, flickr photos tend to show a significant amount of human activity compared to panoramio, which shows more scenic and landmark photography. therefore, we expect panoramio to be a better proxy for architectural beauty. in any case, the number of photos geotagged around each building needs to be considered probabilis- tically: more photos in the vicinity of a building signal a higher probability of that building being depicted. type one classification errors (including pictures that are not about the building measured) and type two classification errors (missing pictures about a building that are posted beyond the distances that we explore in the pa- per) will typically bias down the relationship between image uploads and the actual building beauty metric. therefore estimates in the article need to be interpreted as lower bounds for the quantitative impact of perfectly-measured image uploads focusing on street buildings in the united states, zielstra and hochmair ( ) found the median distance between the camera position and the geotag of flickr images to be of meters. for panoramio, the distance was only meters. a on building beauty. since researchers will tend to focus on the relative ranking by type of building rather than on the exact building beauty rating numbers (that is by definition designed by the survey creator), the downward bias may not be a problem in statistical applications that use image uploads under the laws of large numbers to capture building beauty across building types. for example, consider two sets of different building types, which we convention- ally denominate ”brick” and ”concrete.” assume that each set contains a vast and an identical number of buildings, but that the sum of the number of photos posted around ”brick” buildings is double the number of photos posted around ”concrete” buildings. given the large number of observations, and if there are no reasons to assume that geotagging errors by internet users depend on building materials, the actual number of true photos of ”brick” buildings should also be double (the rate of misclassification across groups should be constant in large samples). further- more, due to the results in the paper, it is likely for the beauty mean of the ”brick” buildings to be substantially higher than the beauty mean for ”concrete” buildings, which is sufficient for many -if not most- applications. nevertheless, the differences in image uploads between the two groups multiplied by the coefficients reported in table of the main text are likely to underestimate their mean building beauty differences, due to attenuation bias. note that if researchers have a priori doubts about the randomness of measure- ment errors across categories (e.g. brick buildings tend to be in high-pedestrian traffic areas or narrower streets and therefore would get more type ii misclassifi- cations), then they should explicitly control for the potential sources of covariance that generate such measurement errors (e.g. control by pedestrian traffic or street width). in most applications, conditioning on neighborhood effects (e.g. zip code or census tract fixed effects) should control for localized differences in photo-taking behavior that could originate other patterns of misclassification error. another interesting and related issue has to do with the possible spatial correla- tion of building beauty. if architectural beauty tends to be geographically clustered, then type ii classification errors (including photos from adjacent buildings) may be more likely for edifices within ”beautiful” clusters. beauty clustering may not be perceived as a problem for many applications if such clustering is systematic. in this case, the beauty of adjacent buildings can be thought of as an additional predictor of a building’s beauty. in other applications, a straightforward way to bypass this issue is by including area fixed effects, so that we study differences in the impact of a building types within each cluster. however, our results in table , panel i, column , suggest that the additional information in annuli further away from the building (which are more likely to capture adjacent buildings) does not generate statistically significant coefficients. in other words, there does not seem to be a substantial con- tribution to explaining building beauty from photos that are more likely to be about neighboring buildings. note that if neighboring beauty were adamant predictors of a building’s beauty, we should have found stronger correlations. after all, -meter image uploads around one building is expected to be a noisier proxy for a buildings beauty than image uploads encompassing wider areas. in conclusion, while building beauty may indeed be spatially correlated, local image uploads at meter distances seem to be sufficient statistics for a building’s beauty perceptions. a image uploads coverage figure a maps the location of all the photos posted to flickr and panoramio websites throughout the u.s. as mentioned in the main text, the total number of photos in panoramio was approximately , and grew up to million by . the total number of photos posted to the flickr website was approximately million. the maps show how the photos are widely distributed across the u.s. the states with the highest number of photos per square kilometer uploaded to panoramio are new jersey ( . ), rhode island ( . ), and massachusetts ( . ). for that same year, the states with the lowest number of photos per square kilometer are north dakota ( . ), kansas ( . ), and mississippi ( . ). a robustness tests this section presents additional robustness tests that validate the use of image uploads as a proxy for building beauty. as a first test, we present the scatter plots of the relationship between image uploads and building beauty. figure a displays the graphic version of the relationship shown in table in the main text. on the vertical axis, we group buildings by the number of photos uploaded in their vicinity, measured using the and panoramio, and flickr websites. the vertical axis captures the sample mean building beauty ratings across buildings in our survey. the size of the dots are commensurate to the number of buildings within each a (a) (b) (c) figure a : map of all u.s. uploaded photos to panoramio in (figure (a)), in (figure (b)), and flickr (figure (c)) photo frequency bin. we display linear and quadratic fit lines. the figures show positive relationships between the number of uploaded photos and mean survey scores. reassuringly, this positive relationship is not driven by outliers. our results in the paper show mostly pictures taken within - meters of a building in panoramio can marginally predict the survey’s building beauty. fig- ure a is analogous to figure in the main text, but uses flickr photo uploads to illustrate the relationship. as in the paper, we run a regression with building beauty on the left hand side and a battery of variables capturing the number of pho- tos within meter-distance annuli (up to meters) on the right hand side. the panel shows a marked decay in the marginal information conveyed by pictures taken further away from a given building. the right panel zooms in to further illustrate the marked decay. our results are therefore robust to using different photo-sharing a figure a : scatter plots of the number of panoramio photos in and against the mean survey score and flickr photos. websites. interestingly, photo frequencies within the first meters are less infor- mative in flickr. this could be consistent with the fact that flickr users are more likely to upload coordinates directly from their phone, corresponding to the place from where they took the photo. therefore, a setback of meters would seem reasonable. conversely, the panoramio application makes it easy for users to pin photos to the exact geolocation of the buildings on a map. alternatively, some of the differences in marginal significance between websites within the first or meters may just be random. nevertheless, in both datasets, the sum of all photos at distances between and meters provides a strong predictor of building beauty, one that is strongly correlated across sites. table a shows the results of the regression that explains building beauty using height, age, and architectural style dummies, as used in table of the main text. we find that spanish colonial revival and beaux-arts architectural styles receive on average a higher building beauty, while modernist and early modernist buildings receive the lowest building beauty. the fitted results from this regression (the explanatory variable values multiplied by the estimated coefficients) are used as our ”predicted” component of beauty and the residuals (orthogonal to the explanatory variables) as our measure of ”residual” beauty. the spanish colonial revival style is a united states architectural stylistic movement arising in the early th century based on the spanish colonial architecture of the spanish colonization of the americas. the beaux-arts style is known as a very rich, lavish and heavily ornamented classical style. a table a : estimates of the relationship between observed character- istics, building beauty and image uploads measures: ols estimates average survey score ( ) building height . ∗∗∗ ( . ) building year . ∗∗ ( . ) art deco . ∗∗∗ ( . ) beaux-arts . ∗∗∗ ( . ) brutalism - . ( . ) chateauesque . ∗∗∗ ( . ) chicago school . ( . ) early modernism . ( . ) gothic . ∗∗∗ ( . ) international style - . ( . ) neo-classicism . ∗∗∗ ( . ) neo-gothic . ∗∗∗ ( . ) postmodern . ∗∗∗ ( . ) renaissance revival . ∗∗∗ ( . ) romanesque revival . ∗∗∗ ( . ) spanish revival . ( . ) observations clusters r-squared . notes: the table shows the correlation between the observed architectural characteristics and building beauty. the table reports only the coefficients of the architectural dummies in the display to save space, but we include all characteristics in the regression. the omitted architectural style, which serves as a baseline is modernism. below each of our estimates and in parentheses, we report standard errors that are robust against heteroskedasticity and clustered on buildings. *** denotes a coefficient significant at the % level, ** at the % level, and * at the % level. a figure a : estimated survey score marginal gains from pictures in range (flickr) as an additional robustness test we repeat the exercise in table , panel i, column of the main text, this time allowing for the range of controls that we used in other columns in the same table. table a presents the estimates of image uploads using two-dimensional annuli (”donuts”) of different lengths around each building in our sample. we then regress building beauty simultaneously against the number of photos uploaded in each annuli. the fact that the coefficients of photo uploads within meters are robust across specifications confirms the highly localized nature of the relationship between image uploads and building beauty, which suggests that we are not confounding contextual factors, regional differences, or neighborhood effects. a respondents in online sample as explained in the text, we used the services of a private vendor (qualtrics) to conduct our survey online. we contracted an ex-ante random sampling of the us population, as opposed to much more expensive methods that explicitly stratify the sample to achieve the average population characteristics ex-post. in practice, this implies that we will have sampling error with regards to matching national characteristics. in addition, the procedure could also include errors introduced by the online sampling methods of the private vendors. heen et al. ( ) conducted an empirical examination of the composition errors of different primary survey providers: survey monkey, qualtrics, and mechanical turk. on average, they find that online surveys tend to oversample the highly- a table a : estimates of the relationship between photo uploads and survey scores, panoramio : ols estimates dependent variable: average survey score ( ) ( ) ( ) ( ) i. photo count for all ratios photos within - meters . ∗∗ . ∗∗ . ∗∗∗ . ∗∗∗ ( . ) ( . ) ( . ) ( . ) photos within - meters . . . . ( . ) ( . ) ( . ) ( . ) photos within - meters . . . . ( . ) ( . ) ( . ) ( . ) photos within - meters - . - . - . - . ( . ) ( . ) ( . ) ( . ) observations clusters r-squared . . . . covariates and weighting: rater effects x x x photo order effects x x weighting by consistency (dif) x notes: the number of photos within each annuli is shown in tens. each column presents a different specification, and the bottom rows describe the covariates and sample restrictions on each model. below each of our estimates and in parentheses, we report standard errors that are robust against heteroskedasticity and clustered on buildings. *** denotes a coefficient significant at the % level, ** at the % level, and * at the % level. a educated and white, but do well in other dimensions. in general, they conclude that “for many applications, the advantages of online surveys (e.g., the efficiency of data collection, lower economic costs, and acceptable approximations to population profiles) far exceed their disadvantages regarding external validity.” table a reports the demographic characteristics of our survey conducted in and the american community survey (acs) -year from to . among the demographic characteristics, we have age reported in brackets (under , - , - , - , and or older) and gender. our survey also includes the race of the respondent, which corresponds to one of the following categories: white/non- hispanic, african american, asian, hispanic, and other. also, the survey reports the education level of respondents, which varies from high-school graduates to re- spondents with some college or completed college and respondents with less than high school. finally, concerning geography, our survey reports whether respondents live in a metropolitan area and their state of residence. some of the survey characteristics do not deviate much from those reported in the census. however, as in heen et al. ( ), the online survey did tend to oversample whites. the survey’s largest discrepancy is with regards to metropolitan area status. the frequency of self-reported metropolitan status is much smaller than we would expect based on random sampling. such discrepancies could arise from different conceptions about how a metropolitan area is perceived by respondents. however, we take the discrepancies at face value to assess the robustness of the findings. in order to see if the existing differences between the census sample and survey in table a impact the covariance between assessed beauty and online photo frequencies we conduct additional exercises to reweigh the survey data to match the frequency of the census demographic categories. in these exercises, we eliminate the respondents who report ”unknown” in the survey (amounting to people). the first row of table a includes gender and age. results are virtually identical to the ones in table of the main text. in the following columns, we continue adding additional variables (race, education, state, and finally metro area) and reassuringly our results remain the same as those in table . when we attempt to match the frequency of a few categories (for instance age and gender) in the first row of table a , we can do it perfectly. naturally, as we increase the number of categories the census bins become more sparse, and we cannot perfectly match their frequency. for instance, in the last row of table a , we have about , census bins and a sample of individuals. nevertheless, reweighing a table a : census and survey comparison percentage of individuals survey (acs) -year gender unknown . % [ . %- . %] male . % . % [ . %- . %] female . % . % [ . %- . %] age unknown . [ . %- . %] and older . . [ . %- . %] - . . [ . %- . %] - . . [ . %- . %] - . . [ . %- . %] under . . [ . %- . %] race unknown . [ . %- . %] white, non-hispanic . . [ . %- . %] african american . . [ . %- . %] asian . . [ . %- . %] hispanic . . [ . %- . %] other . . [ . %- . %] metro area unknown . . [ . %- . %] yes . . [ . %- . %] no . . [ . %- . %] education level unknown . [ . %- . %] high school degree . . [ . %- . %] college degree or higher . . [ . %- . %] other . . [ . %- . %] notes: the table presents the percentage of respondents in the survey and the american community survey (acs) -year from to broken down by their demographic and geographic characteristics. a does eliminate expected biases in the relative frequencies of characteristics. as stated, concerns about sample composition turn out not to be relevant in practice: our estimates remain extremely robust with all alternative weight rebal- ancing schemes. in the bottom panel of table a , we lose an additional survey respondent (hence the decline in observations) for which we cannot find its corre- sponding weights in the acs sample. that is, there no respondent in the acs with the same demographic characteristics. for instance, we can compare the coefficients in the bottom panel, where we thoroughly reweigh using census frequencies concerning all variables in the sam- ple. the coefficients of the impact of survey scores on photo frequencies are . , . , and . in panoramio, flickr, and their first principal component factor, respectively. these are comparable to . , . , and . in the unweighted counterpart results in table , column ( ) of the main text. in the worst-case sce- nario, the differences are below one-sixth of the estimated standard deviation of the parameter. we conclude that –in our case– the raw online sample provides researchers with valid variation for investigating issues related to the environmental covariates of perceived architectural beauty. moreover, the use of similar online rating exercises can provide researchers with a cost-effective way to study architectural beauty in other contexts as well. conducting off-line image ratings with significant respondent samples (e.g., over ) and many image ratings (exceeding per respondent), might make these exercises prohibitively expensive, thereby curtailing such inves- tigations. re-weighting exercises –as we do here– can then be conducted to assess the robustness of results to sampling conditions. a table a : main results reweighing by survey characteristics dependent variable: average survey score ( ) ( ) ( ) panoramio photo uploads flickr photo uploads pcf photo uploads reweighting by gender and age . ∗∗∗ . ∗∗∗ . ∗∗∗ ( . ) ( . ) ( . ) observations clusters r-squared . . . reweighting by gender, age, . ∗∗∗ . ∗∗∗ . ∗∗∗ and race ( . ) ( . ) ( . ) observations clusters r-squared . . . reweighting by gender, age, . ∗∗∗ . ∗∗∗ . ∗∗∗ race, and education ( . ) ( . ) ( . ) observations clusters r-squared . . . reweighting by gender, age, . ∗∗∗ . ∗∗∗ . ∗∗∗ race, education, and state ( . ) ( . ) ( . ) observations clusters r-squared . . . reweighting by gender, age, race, . ∗∗∗ . ∗∗∗ . ∗∗∗ education, state, and metro area ( . ) ( . ) ( . ) observations clusters r-squared . . . covariates: rater effects x x x photo order effects x x x notes: the dependent variable is average survey score. observations are building and rater specific. each column presents a different specification, where we vary the source of image uploads. the bottom rows describe the covariates in each model. below each of our estimates and in parentheses, we report standard errors that are robust to heteroskedasticity and clustered at the building level. *** denotes a coefficient significant at the % level, ** at the % level, and * at the % level. a figure a : top survey photos ranked by mean respondent scores. figure a : bottom survey photos ranked by mean respondent scores. a references et al. larson, m. ( ). the benchmark as a research catalyst: charting the progress of geo-prediction for social multimedia. f. goodchild, m. ( ). citizens as sensors: the world of volunteered geography. geojournal, : – . heen, m. s. j., lieberman, j. d., and miethe, t. d. ( ). a comparison of different online sampling approaches for generating national samples. ccjp, (september): – . zielstra, d. and hochmair, h. h. ( ). positional accuracy analysis of flickr and panoramio images for selected world regions. journal of spatial science, ( ): – . a panoramio, flickr, and image uploads as probability fields: potential pitfalls, promises, and solutions image uploads coverage robustness tests respondents in online sample the journal of academic social science studies international journal of social science doi number:http://dx.doi.org/ . /jasss number: , p. - , autumn i araştırma makalesi / research article yayın süreci / publication process yayın geliş tarihi / article arrival date - yayın kabul tarihi / the published date . . . . yayınlanma tarihi / publication of acceptance date . . the secret of the beauty of the speech of the prophet ســــــــــّر جمالــــــية البيـــــــان النبــــــــــوي dr. fatima zahra nahmar orcid id: https://orcid.org/ - university of blida algeria department of arabic language and literature, zahraanahmar@gmail.com abstarct the prophet, may allah's peace and blessings be upon him, singled out a number of characteristics in which the prophets, messengers, and creation were distinguished by the most important of which is the prophet's hadith. this is in honor of his position and honor for his position. and the impact of the human, scientific, spiritual and moral perfection of the prophet (pbuh) at the height of his position, addresses the following problems: what is the secret of the aesthetics of the prophet's statement? and what made him influential in the soul key words: the speech of the prophet, the secret, the beauty, the influential, the soul الدكتكرة: فاطمة الزىراء نيمار الجزائر - -يدةػػػػػػػػػػػػػػلبمعة اػػجام قسـ الّمغة العربية ك آدابيا محاضرة أ zahraanahmar@gmail.com https://orcid.org/ - ../zahraanahmar@gmail.com mailto:zahraanahmar@gmail.com fatima zahra nahmar الممخص : ،مف أىميا الحديث النبكي بيا األنبياء كالرسل كالخمق أجمعيف لخصائص فاؽبجممة مف اكجل رسكلو الكريـ دمحم ملسو هيلع هللا ىلص اختص هللا عزّ ، فيذه المداخمة ىي محاكلة لمغكص في أعماؽ خمق هللا خيرُ ك األنبياء كالرسل كىك خاتـُ كيف ال ،تكريًما لمقامو كتشريًفا لمكانتو كىذا االكتماؿ ؼ إلى معرفة مكانة الحديث النبكي الشريف، كمدى تأثير ، تيدالبياف النبكي لمكشف عف خبايا جماليتو كتأثيره في النفكس لنبكي ؟ اإلنساني كالعممي كالركحاني كالُخمقي لمنبي عميو الصالة كالسالـ في عمّك منزلتو ، تعالج اإلشكالية اآلتية: ما سّر جمالية البياف ا كما الذي جعمو مؤثرا في النفكس ؟ النفكس التأثير الجمالية السر بكي البياف الن الكممات المفتاحية : مقدمة : َفَأْعِرْض ﴿ لقد تحّدث القرآف الكريـ في نصكص عديدة عف سمّك البياف النبكي كعمّك مكانتو، إذ كصفو بالقكؿ البميغ في قكلو تعالى : ُهْم َوِعْظُهْم َوُقْل ََلُْم ِف َأنْ ُفِسِهْم قَ ْوًلا بَِليغاا كالبياف الناجع األثر في فيذه اآلية ىي " شيادة هللا لرسكلو ملسو هيلع هللا ىلص بغاية القدرة عمى الكالـ البميغ ، ، ﴾َعن ْ ره كالكالـ يختمف تأثي ﴾ِف َأنْ ُفِسِهْم قَ ْوًلا بَِليغاا﴿ أعماؽ النفكس، فقد أمره هللا تعالى أف يعع ىؤالء المنافقيف ليرتدعكا عف نفاقيـ، كأف يقكؿ ليـ باختالؼ أفياـ المخاطبيف، كىذه فئة مريضة معقدة األساس، يحتاج إفياميا كالتأثير فييا إلى قكة أسمكب كبالغة بياف فكؽ غيرىـ مف . لبالغة "لحكمة االناس، فكاف أمره ملسو هيلع هللا ىلص بيذا األمر شيادة لو بغاية القدرة عمى الكالـ البميغ، كاألسمكب العميق األثر في النفكس، مع ا كشيد ذلؾ أيضا صحابتو رضكاف هللا عمييـ كىـ جيل فصاحة كبياف ، كىـ الذيف تذكقكا إعجاز القرآف الكريـ كخضعكا لبيانو المعجز، َصمهى َّللاهُ َعَمْيِو َكَسمهـَ َيْكًما َبْعَد َصاَلِة الَغدَ فيذا عرباض بف سارية " اِة َمْكِعَظًة َبِميَغًة َذَرَفْت ِمْنَيا الُعُيكُف َكَكِجَمْت ِمْنَيا َقاَؿ: َكَعَظَنا َرُسكُؿ َّللاهِ . " الُقُمكبُ فما الذي جعل البياف النبكي مؤثرا في النفكس ؟ كما سبب سمّكه كعمّك مكانتو ؟ كما سّر جماليتو ؟ ز العقل البشري عف ييا كجدُت أّف السّر أعمق بكثير، يعجِ بعد االّطالع عمى الكتب التي تصّب في المكضكع كقراءتيا كالتأّمل ف الكشف عنو، ألّنو يتعمق بسّيد الخمق كأعظـ قدكة لمّناس أجمعيف، كصل إلى مرتبة سامية عظيمة ، كقد بدا لي أّنو يمكف جعمو في ثالثة أمكر متمثمة فيما يمي : االكتمال اإلنساني والعممي والروحاني والخمقي : يمّثل الكماؿ المطمق في التككيف سمّك البياف النبكي ناتج عف سمّكه ملسو هيلع هللا ىلص، كعمّك مكانتو ناتج عف عظمتو ملسو هيلع هللا ىلص، فدمحم عميو الصالة كالسالـ قتو كدقة تصكيره، كفي قكة عقمو اإلنساني كالعممي كالركحاني كالخمقي، فيك المثل الكامل في شرؼ نسبو ، كفي كـر أسمائو، كفي جماؿ ِخم طرتو، كفي فصاحة لسانو، كفي بالغة بيانو، كفي كجدانو، كفي شعكره، كفي نفسيتو، كفي تعّبده، كفي شريعتو، ّدة ذكائو، كفي استقامة فِ كحِ صالة كالسالـ : " أّدبني رّبي كقد ُركَي عنو عميو ال يضاؼ إلى ذلؾ أّف هللا تعالى تعّيده منذ الصغر بالتربية المثمى كالتأديب السامي ُ يَ ْعِصُمَك ِمَن النهاسِ ﴿ : كما أحاطتو العناية اإلليية الربانية لقكلو تعالى فأحسف تأديبي " . ﴾ َواَّلله نسبو الزكي الشريف : أ األخالؽ مبنيا عمى اصطفاءة مف األصكؿ الكريمة الفركع الزكيّ اإلليي ، فقد اصطفى هللا تعالى ءيتمّيز نسب دمحم ملسو هيلع هللا ىلص باالصطفا عمييما بالنسبة إلى إسماعيل كالنبي النبكة كالرسالةكيضاؼ إلى ذلؾ الكريمة، كالفضائل اإلنسانية السامية، كالطباع الفطرية السميمة، .السالـ ـِ اْلَحَجِر َعَمْيِو َقْبَل النُُّبكهةِ َباب َفْضِل َنَسِب النهِبيِّ َصمهى هللُا َعمَ كقد كرد في صحيح مسمـ مف" " أّنو عميو الصالة كالسالـ ْيِو َكَسمهـَ، َكَتْسِمي «ِني َىاِشـٍ َىاِشـٍ، َكاْصَطَفاِني ِمْف بَ ِإفه هللَا اْصَطَفى ِكَناَنَة ِمْف َكَلِد ِإْسَماِعيَل، َكاْصَطَفى ُقَرْيًشا ِمْف ِكَناَنَة، َكاْصَطَفى ِمْف ُقَرْيٍش َبِني »قاؿ: ركاه مسمـ . ُمَحمهُد ْبُف َعْبِد َّللاهِ ْبِف َعْبِد الُمطهِمِب ْبِف »باب مبعث النبي ملسو هيلع هللا ىلص" فقاؿ : " في ذكر البخاري في صحيحو نسب دمحم عميو الصالة كالسالـ ْبِف َكعِب ْبِف لَؤيِّ ْبِف غاِلِب ْبِف ِفْيِر ْبِف َماِلِؾ ْبِف النهْضِر ْبِف ِكَناَنَة ْبِف ُخَزْيَمَة ْبِف ُمْدِرَكَة ْبفِ َىاِشـِ ْبِف َعْبِد َمَناِؼ ْبِف ُقَصيِّ ْبِف ِكاَلِب ْبِف ُمرهةَ . « ِإْلَياَس ْبِف ُمَضَر ْبِف ِنَزاِر ْبِف َمَعدِّ ْبِف َعْدَنافَ ْبِف َأِبي َكَداَعَة، َقاَؿ: َقاَؿ اْلَعبهاُس: َبَمَغُو َصمهى هللُا َعَمْيِو َكَسمهـَ َبْعُض َما َيُقكُؿ َعِف اْلُمطهِمبِ ركى اإلماـ أحمد بف حنبل في مسنده بسند " ْبِد اْلُمطهِمِب، ِإفه هللَا َخَمَق اْلَخْمَق َعْبِد هللِا ْبِف عَ النهاُس، َقاَؿ: َفَصِعَد اْلِمْنَبَر، َفَقاَؿ: " َمْف َأَنا؟ " َقاُلكا: َأْنَت َرُسكُؿ هللِا، َفَقاَؿ: " َأَنا ُمَحمهُد ْبفُ the secret of the beauty of the speech of the prophet ي ِفي َخْيِر َقِبيَمٍة، َكَجَعَمُيـْ ُبُيكًتا، َفَجَعَمِني ِفي َخْيِرِىـْ َفَجَعَمِني ِفي َخْيِر َخْمِقِو، َكَجَعَمُيـْ ِفْرَقَتْيِف، َفَجَعَمِني ِفي َخْيِر ِفْرَقٍة، َكَخَمَق اْلَقَباِئَل، َفَجَعَمنِ َفَأَنا َخْيُرُكـْ َبْيًتا َكَخْيُرُكـْ َنْفًسا " َبْيًتا، . أسماؤه الكريمة: ب لمنبي عميو الصالة كالسالـ أسماء كثيرة تعكس شرؼ المسمى كمدى تحميو بالفضائل كاآلداب كالميزات، أشيرىا خمسة كىي خاصة بو َأَنا ُمَحمهٌد، َكَأَنا َأْحَمُد، َكَأَنا اْلَماِحي، الهِذي ُيْمَحى ِبَي اْلُكْفُر، َكَأَنا »َكَسمهـَ، َقاَؿ: َأفه النهِبيه َصمهى هللُا َعَمْيوِ كحده، جاء في صحيح مسمـ " " اْلَحاِشُر الهِذي ُيْحَشُر النهاُس َعَمى َعِقِبي، َكَأَنا اْلَعاِقُب َكاْلَعاِقُب الهِذي َلْيَس َبْعَدُه َنِبي عمة ، كاألميف، كالمزّمل، كالمدّثر، كالرؤكؼ، ، كالرحمة، كالنّ ر: المذكّ خرى فقد يشاركو فييا غيره مف األنبياء منيا كأّما األسماء األ ، كالشفيع كالمشفهع،كالصادؽ كالمصدكؽ ، الشاىد، كالمبّشر، كالنذير، كالمبيف، كالداعي إلى هللا ، كاليادي، كالسراج المنير، كالرحيـ ،كالشييد . المصطفى كالمختار ك سيرتو وعظمة أخالقو : ج مقًة كصكرًة كنشأًة كتربيًة ، خُمُقو القرآف يرضى لرضاه كيغضب لغضبو، ُعرؼ بالصدؽ، كاف عميو الصالة كالسالـ أكمَل الناس خِ صفات المذمكمة، لـ ُيعْب قّط في أقكالو كاألمانة، كالكقار، كالحمـ، كالحياء، كالرحمة، كالعفك، كالتكاضع، كالعدؿ، كترؾ الفكاحش كالظمـ كال ـِ ْبِف َعاِمٍر، َقاَؿ: َأَتْيُت َعاِئَشَة، َفُقْمُت: َيا ُأـه اْلُمْؤِمِنيَف، َأْخِبِريِني ِبُخُمِق رَ ، " كال في أفعالو كال في أخالقو ُسكِؿ هللِا َصمهى َعْف َسْعِد ْبِف ِىَشا " ُخُمُقُو اْلُقْرآفَ هللُا َعَمْيِو َكَسمهـَ، َقاَلْت: " َكافَ .ركاه أحمد في مسنده وا ِمْن َحْوِلكَ ﴿كقد كصفو هللا تعالى فقاؿ : . ﴾ َوإِنهَك لََعَلى ُخُلٍق َعِظيمٍ ﴿كقكلو أيضا : ﴾ َوَلْو ُكْنَت َفظًّا َغِليَظ اْلَقْلِب ًَلنْ َفضُّ بة كلـ يتتممذ عمى يد أحد، كفي ذلؾ حكمة كبيرة حتى ال يقكؿ الكافركف كالجاحدكف أضف إلى ذلؾ فقد كاف أمّيا لـ يتعمـ القراءة كال الكتا بأّف ىذا الذي يّدعي ما يّدعي عّممو بشر . نبوتو وتبميغو لمرسالة الربانية العالمية الخاتمة : د أ بو الرؤيا الصادقة، فكاف ال يرى رؤيا إاّل كيتحقق لما بمغ عميو الصالة كالسالـ سف األربعيف نّبأه هللا تعالى كأكحى إليو، كأكؿ ما ُبد َوَما َأْرَسْلَناَك ﴿ ليحمل رسالة رب العالميف كيبمغيا إلى الّناس كاّفة قاؿ تعالى : صدُقيا، كبعد ستة أشير نزؿ عميو جبريل بالكحي القرآني راا َوَنِذيراا ) يَ ﴿: كقكلو أيضا، ﴾اِس ًَل يَ ْعَلُمونَ ِإًله َكافهةا لِلنهاِس َبِشرياا َوَنِذيراا َوَلِكنه َأْكثَ َر النه ا َوُمَبشِّ َها النهِبُّ ِإَّنه َأْرَسْلَناَك َشاِهدا ( َوَداِعياا ِإََل اَّللِه ِبِِْذنِِه َأي ُّ ا ُمِنرياا . ﴾ َوِسَراجا أعالىا كأعظميا القرآف الكريـ الحاكي لعمـك األكليف كاآلخريف كلتأييد رسالتو الربانية أُعطي معجزات معنكية كحسية ، أّما المعنكية ف ، أّما الحسية ﴾ َوإِنهَك لََعَلى ُخُلٍق َعِظيمٍ ﴿كتحدى بو الجف كاإلنس أف يأتكا بمثمو فعجزكا، يضاؼ إلى ذلؾ كماالت أخالقية لقكلو تعالى : قاؤه عميو الصالة ك السالـ رّبو ألمتو حيف تأخر المطر، كمنيا ما ىك كانشقاؽ القمر، كرد الشمس بعد مغيبيا، كاستس فمنيا ماىك سماكي َوَأنْ َزَل اَّللهُ َعَلْيَك اْلِكتَاَب ﴿ ، قاؿ تعالى : أرضي كنبع الماء مف بيف أصابعو، كتسبيح الحصى في كفو، كحنيف الجذع شكقا إليو كغيرىا اَواْلِْْكَمَة َوَعلهَمَك َما ََلْ َتُكْن تَ ْعَلُم وَ . ﴾َكاَن َفْضُل اَّللِه َعلَْيَك َعِظيما فصاحتو المنفردة : يرى العقاد أّف الفصاحة ىي صفة تجتمع في الكالـ كىيئة النطق بو كفي مكضكعو، كقد تكامل ذلؾ في فصاحة دمحم إذ ُيعّد أفصح َما »ك خير مف كصفو ىك عائشة رضي هللا عنيا إذ قالت : ، ناطق بالضاد كأعرب العرب، فقد ُأكتي جماؿ النطق كالكالـ كالمكضكع ـُ ِبَكاَلـٍ يُ َصمهى َّللاهُ َعَمْيِو َكَسمهـَ َيْسُرُد َسْرَدُكـْ َىَذا، َكَلِكنهُو َكاَف َيَتَكمه . «َبيُِّنُو، َفْصٌل، َيْحَفُظُو َمْف َجَمَس ِإَلْيوِ َكاَف َرُسكُؿ َّللاهِ ف القكؿ، كال يقصد إلى تزيينو، كال يبغي إليو كسيمة مف كسائل الصنعة، كال يجاكز ال يتكمّ كالسالـ أفصح العرب، " كاف عميو الصالة و الُفجاءة كما َيْبَده مف أغراض الكالـ عف ال يعرض لو في ذلؾ سَقط كال استكراه؛ كال تستزلُّ بو مقدار اإلبالغ في المعنى الذي يريده، ثـّ أنت ال عف النمط الغريب كالطريقة المحكمة، بحيث ال يجد النظر إلى كالمو طريقًا يتصفح منو صاعدًا أك منحدرًا؛ ثـّ األسمكب الرائع، ك إنساني مف مقدارٌ ا يخرج بو الكالـ كليس فكقو المعاني التي ىي إلياـ النبكة، كنتاج الحكمة، كغاية العقل، كما إلى ذلؾ ممّ تعرؼ لو إالّ . " براعة القصدالبالغة كالتسديد ك كما ىذه الفصاحة إاّل تكفيقا مف هللا تعالى، إذ بعثو إلى العرب الذيف ينقادكف مف ألسنتيـ، كليـ في ذلؾ مقامات مشيكرة في الفصاحة fatima zahra nahmar ة، فكاف عميو كالبياف، كمتفاكتكف في معرفة المغة فمنيـ الفصيح كاألفصح، كمنيـ المضطرب كالجافي، كمنيـ الخالص في منطقو كذك المكث الصالة كالسالـ يعمـ حقائق المغة كأسرارىا، فيخاطب كل قـك بمحنيـ كعمى مذىبيـ، فيككف أفصحيـ خطابا، كأبينيـ عبارًة، كأسدىـ لفظا، . كلـ ُيعرؼ ذلؾ لغيره مف العرب يا طبيعية فيو؛ كألفّ حيانًا كثيرة كقميمة: ألنّ النقص الذي يعتري الفصحاء مف جيتيا أ عفإنفرد عف فصحاء العرب مف حيث أّنو " ُمنّزه صمى -ا انفرد بو نبينا كىي مف الجية المغكية ممّ ... أثر إنساني يصدر عنيا، مف كرائيا تمؾ النفَس العظيمة الكاممَة التي غمبت عمى كلّ نهما أنزؿ القرآف بمسانو لساف عربي م -هللا عميو كسمـ . " بيففي عربيتو، كما يمنعو منيا كا ىناؾ عامالف أساسياف في الفصاحة : األكؿ تمّثل في أّنو تكفيق مف هللا ك إلياـ منو لتككف الحجُة بو أظيَر كالبرىاَف القاطَع عمى أفصح القبائل كأخمصيا في بَ كتقمه -ملسو هيلع هللا ىلص -كقد نشأ النبي رسالتو، أّما الثاني فككنو مف قريش التي ىي مف أفصح المغات كألينيا، " جو في بني تزكّ منطقًا، كأعذبيا بيانًا، فكاف مكلده في بني ىاشـ، كأخكالو في بني زىرة، كرضاعو في سعد بف بكر، كمنشؤه في قريش، كمُ . " أسد، كمياجرتو إلى بني عمرك، كىـ األكس كالخزرج مف األنصار، لـ يخرج عف ىؤالء في النشأة كالمغة منقطعة النظير :بالغتو ال النبي عميو الصالة كالسالـ أفصح العرب ك أبمغيـ بيانا كخطابا، بمغ مف البياف اإلنساني أعمى مراتبو ال يبمغ شأكه أحد، فيك يتبكأ المرتبة الثانية بعد القرآف الكريـ. ز عػػف بمكغيػػا فصػػحاء العػػرب كبمغاؤىػػا، فيػػك يجمػػع بػػيف يػػرى مصػػطفى صػػادؽ الرافعػػي أّف لمبالغػػة النبكيػػة نسػػٌق خػػاص متمّيػػز يعجػػ أّمػا المغػُة فيػي لغػة الكاضػع بػالفطرة القكيػة المسػتحكمة، كالمنصػرؼ معيػا الخالص مف سّر المغػة كالبيػاف كالحكمػة كيشػرح ذلػؾ كيقػكؿ : " النبػكة، ا الحكمػة فتمػؾ حكمػةٌ لػذكاء كاإلليػاـ، كأّمػا البيػاف فبيػاف أفصػح النػاس نشػأة، كأقػكاىـ مػذىبًا، كأبمغيػـ مػف اباإلحاطة كاالستيعاب، كأّمػ . " في اإلنساف مف فكؽ اإلنسانية. هللا، كأمرٌ الكحي كتأديبُ كتبصيرُ ّزه عف معانيو، كجّل عف الصنعة، كنُ ر عددُ حركفو ككثُ كىك الكالـ الذي قّل عددُ أسمكب كالمو فقاؿ : " )ق ت(كصف الجاحع ر بالتكفيق. كىك الكالـ الذي ألقى هللا سّ د بالتأييد، كيُ يّ بالعصمة، كشُ بكالـ قد حفّ عف ميراث حكمة، كلـ يتكمـ إالّ الّ ف... فمـ ينطق إالتكمّ اه بالقبكؿ كجمع لو بيف الميابة كالحالكة، كبيف حسف األفياـ، كقمة عدد الكالـ، مع استغنائو عف إعادتو، كقمة حاجة عميو المحبة، كغشّ كدتو.السامع إلى معا الطكاؿ بالكالـ القصار، كال طبَ الخُ ت بو قدـ، كال بارت لو حجة، كلـ يقـ لو خصـ، كال أفحمو خطيب، بل يبذُّ لـ تسقط لو كممة، كال زلّ أعدؿَ لفظا، كال نفعا، كال أقصدَ أعـه كالـ قطّ بلـ يسمع الناس بالصدؽ... ثـّ إالّ بما يعرفو الخصـ، كال يحتجّ يمتمس إسكات الخصـ إالّ و كزنا، كال أجمل مذىبا، كال أكـر مطمبا، كال أحسف مكقعا، كال أسيل مخرجا، كال أفصح معنى، كال أبيف في فحكى، مف كالمو صّمى هللا عمي . " كسّمـ كثيرا ة القكؿ، فقد ا فصاحة المساف كبالغكأمّ في فصاحتو كبالغتو قائاًل : " )ق ت(تحّدث القاضي عياض بف مكسى اليحصبي السبتي يجاز مقطع، كنصاعة كاف صمى هللا تعالى عميو كسمـ مف ذلؾ بالمحل األفضل، كالمكضع الذى ال يجيل، سالمة طبع، كبراعة منزع، كا ة بمسانيا،أمّ ـ ألسنة العرب، فكاف يخاطب كلّ مّ ببدائع الحكـ، كعُ ّص ف، أكتى جكامع الكمـ، كخُ لفع، كجزالة قكؿ، كصحة معاف، كقمة تكمّ . " مف أصحابو يسألكنو فى مكطف عف شرح كالمو كتفسير قكلو ى كاف كثيرٌ كيحاكرىا بمغتيا، كيبارييا فى منزع بالغتيا، حتّ عمى جية الصناعتيف المغكية -ملسو هيلع هللا ىلص -نقمو مف كالـ النبي إذا نظرت فيما صحّ لمرافعي مكضٌع يفّصل فيو الكالـ النبكي فيقكؿ : " الصمة بيف الجممة كاضحَ األجزاء في تأليف الكممات: فخـَ التركيب. متناِسبَ الكضع جزؿَ كالبيانية، رأيتو في األكلى ُمسدَد المفع ُمحكـَ مضطربًا؛ كال لفظة مستدعاة لمعناىا أك مستكرىة عميو؛ كال كممة ال ترى فيو حرفاً المفع كمعناه كالمفع كضريبو في التأليف كالنسق، ثـّ ه في االستعماؿ؛ كرأيتو في الثانية حسف المعِرض بيف الجممة، كاضَح التفضيل، ظاِىَر الحدكد جيَد يًا لسرّ منيا أداة لممعنى كتأتّ غيُرىا أتـّ . ناصع البياف " الرصِف، متمكف المعنى؛ كاسع الحيمة في تصريفو، بديَع اإلشارة، غريب الممحة، ، أنت أضفت إلييا ما ىناؾ، مف سمك المعنى؛ كفصل الخطاب، كحكمة القكؿ، كدنك المأخذ، كا صابة السرّ فإذابعدىا يضيف قائال : " بو في اإلفصاح، كمنحاه في التعبير، مما ُخّص -ملسو هيلع هللا ىلص -طبقة مف الكالـ، كما يمتحق بيذه كأمثاليا مف مذىبو كفصل التصرؼ في كلّ رأيت مف جممة -ف ف عظمة النفس، ككماؿ العقل، كثقكب الذىف كمف المنزَعة الجيدة، كالمساف المتمكّ ة، مدكف الفصحاء، ككاف لو خاّص المغة كمف البياف كمف ما يتييأ في ُمثكؿ أغراضو كتساكؽ معانيو لبميغ مف البمغاء، إذ يجمع الخالص مف سرّ مّ ذلؾ نسقًا في البالغة ق the secret of the beauty of the speech of the prophet . " بعضيا إلى بعض -الحكمة أّنو س محمكد العقاد أّف السمة الغالبة عمى أسمكب النبي ملسو هيلع هللا ىلص في كالمو المحمكد بيف أيدينا ىي سمة اإلبالغ كأقكى ما فييا يرى عبا ، كيعرفيا قائال : " اجتماع المعاني الكبار في الكممات القصار، بل اجتماع العمـك الكافية في بضع كممات، كقد أكتي جكامع الكمـ . سطيا الشارحكف في مجمدات " يب َصمهى هللُا َعَمْيِو َكَسمهـَ، َيُقكُؿ: كقد جاء شرح لمعناىا في حديث أبي ىريرة رضي هللا عنو إذ قاؿ : " ُبِعْثُت ِبَجَكاِمِع »َسِمْعُت َرُسكَؿ َّللاهِ ـِ، َكُنِصْرُت ِبالرُّْعِب، َكَبْيَنا َأَنا َناِئـٌ ُأِتيُت ِبَمفَ ـِ: َأفه َّللاهَ « اِتيِح َخَزاِئِف اأَلْرِض َفُكِضَعْت ِفي َيِديالَكِم َقاَؿ َأُبك َعْبِد َّللاهِ: " َكَبَمَغِني َأفه َجَكاِمَع الَكِم . َنْحَك َذِلَؾ "َيْجَمُع األُُمكَر الَكِثيَرَة، الهِتي َكاَنْت ُتْكَتُب ِفي الُكُتِب َقْبَمُو، ِفي اأَلْمِر الَكاِحِد، َكاألَْمَرْيِف، َأْك رار حّدد دمحم الصالح الصديق معناىا قائال : " المراد بجكامع الكمـ القرآف الكريـ سمي بو إليجازه كاحتكائو عمى المعاني الكثيرة، كاألس خبار...ككالـ الرسكؿ أيضا الدقيقة، كاإلشارات المطيفة، كالشتمالو أيضا عمى ما جمعتو الكتب السماكية مف العمـك السنية، كالمعاني األ ( ِإْن َوَما يَ ْنِطُق َعِن اَْلََوى )﴿ مدعما بقكلو تعالى : جكامع، قميمة المفع، كثيرة المعنى، بعيدة المرمى، صادقة ال تحتمل الصدؽ ك الكذب" . ﴾( ُهَو ِإًله َوْحٌي يُوَحى ) كقيل بأّف الجكامع يقصد بيا القرآف حينما جمع هللا تعالى المعاني الكثيرة جاء ذلؾ المعنى في صحيح مسمـ حينما ُشرح الحديث نفسو , في ألفاظ يسيرة، ككالـ عميو الصالة كالسالـ كاف بالجكامع بمعنى قميل المفع كثير المعنى" كر مثاليف لمتكضيح فيقكؿ: " كقد أكرد مصطفى صادؽ الرافعي بعض األمثمة عف جكامع الكمـ النبكية كشرحيا شرحا بالغيا كبيانيا أذ كالكطيُس: ىك التنكر مجتمُع النار كالكقكد، فميما كانت صفة الحرب، فإف ىذه كقكلو في صفة الحرب يـك حنْيف: " اآلف َحِمي الكطيس " ارية أك نارًا دمكية!مشبكبة مف البالغة تأكل الكالـَ أكال، ككأنما ىي تمثل لؾ دماء ن الكممة بكل ما يقاؿ في صفتيا، ككأنما ىي نار كقكلو في حديث الفتنة: ىْدنة عمى َدخف، كاليدنة: الصمح كالمكادعة كالدخف: تغير الطعاـ إذا أصابو الدخاف في حاؿ طبخو فأفسد و، كذلؾ أف الصمح إنما كىذه العبارة ال َيعدليا كالـ في معناىا، فإف فييا لكنًا مف التصكير البياني لك أذيبت لو المغة كميا ما كفت ب طعمو. ٍة يككف مكاَدعة كلينًا؛ كانصرافًا عف الحرب، ككفًّا عف األذى؛ كىذه كميا مف عكاطف القمكب الرحيمة فإذا بني الصمح عمى فساد، ككاف لعم و إال رائحة ىذا غمب ذلؾ عمى القمكب فأفسدىا، حتى ال يسترح غيره مف أفعاليا، كما يغمب الدخف عمى الطعاـ، فال يجد آكم مف العمل، . " الدخاف، كالطعاـ مف بعد ذلؾ مشكب مفسد البياف في العبارة معنى ثالث، كىك النكتة التي مف أجميا اختيرت ىذه المفظة بعينيا، ككانت سرّ ثـّ بعدىا يكاصل الشرح فيقكؿ : " فيذه حرٌب قد طفئت نارىا بما سكؼ أف تطفأ الحرب. الصمح ال يككف إالّ عبارة تككف في ىذا المعنى كذلؾ أفّ يا، كبيا فضمت كلّ كمّ يستكِقد فيستعر فإذا ىي نار تمظى، كما كاف فكقو الدخاف فإفّ ار تخبك بو قمياًل، ثـّ كما يمقى الحطب الرطب عمى النّ يككف فييا نارًا أخرى. معنى مف المعاني يمكف أف ليدنة التي تمؾ صفتياالنار كال َجـر مف تحتو، كىذا كمو تصكير لدقائق المعنى كما ترى، حتى ليس في ا " يتصكر في العقل إال كجدت المكف البياني يصكره في تمؾ المفظة لفظة " الَدخف ". جمع دمحم الصالح صديق األحاديث النبكية الدالة عمى جكامع الكمـ في كتابو " جكامع الكمـ النبكية" ، أذكر منيا عمى سبيل التمثيل ال حصر : ال  ُبعثت بجكامع الكمـ " ركاه البخاري كمسمـ "  الصكـُ ُجّنة " ركاه البخاري "  المؤمُف لممؤمف كالبنياف يشّد بعُضو بعضا " أخرجو البخاري كمسمـ كالترمذي كالنسائي عف أبي مكسى "  أكمُل المؤمنيف إيمانا أحسُنيـ ُخمقا " أخرجو الترمذي كأحمد كابف حباف "  ْف قل " أخرجو البخاري كمسمـ " أحبُّ األ عماؿ إلى هللا أدكُميا كا  مثُل القمب مثُل الريشة تقّمبيا الرياُح بفالة " ركاه ابف ماجة عف أبي مكسى األشعري "  مْف شاب شيبة في اإلسالـ كانت لو نكرا يـك القيامة " أخرجو الترمذي "  ُيبعث كل عبد عمى ما مات عميو " ركاه مسل عف جابر " fatima zahra nahmar  أد األمانة إلى مف ائتمنؾ، كال تخف مف خانؾ " أخرجو جمع مف األئمة الكبار كأتي داكد كالترمذي ك الدارقطني كالطبراني " كالبييقي كغيرىـ  خيُر الصداؽ أيسُره " أخرجو أبك داكد كصححو الحاكـ "  لحاكـ " إّياؾ ككلُّ أمر ُيعتذر منو " ركاه الديممي في مسند الفردكس كسنده حسف كا  الصمُت حكمة كقميٌل فاعُمو " أخرجو العسكري عف أبي الدرداء "  أفمح مف ُرزؽ لّبا " أخرجو البخاري كالبييقي "  مف تشّبو بقـك فيك منيـ " أخرجو أبك داكد كصححو ابف حباف "  ف ابف عمر " ما عاؿ مف اقتصد " ركاه أحمد عف ابف مسعكد، كركاه الخطيب عف أنس، كالطبراني كالبيقيي ع  أعطكا األجيَر أجَره قبل أْف يجفه عرّقو " ركاه ابف ماجة "  العمماء أمناء أمتي " أخرجو الديممي  اإلسالـ َيعمك كال ُيعمى " أخرجو الدارقطني " كخالصة القكؿ فإّف الغكص في سّر جمالية البياف النبكي بحر عميق ال قعر لو، ف فيض، كقطرة مف بحر، كقد خرجت بالنتائج اآلتية :كمحاكلتي لمكشف عنو ىك غيض م ي دمحم عميو الصالة كالسالـ يمثل الكماؿ المطمق في التككيف اإلنساني كالعممي كالركحاني كالُخمقي كقد تجّسد ذلؾ في البياف النبكي الذ فاؽ كالـ أفصح الفصحاء كأبمغ الُبمغاء . المرتبة الثانية بعد القرآف الكريـ البياف النبكي في فصاحتو كبالغتو يتبكأ لمبالغة النبكية نسق خاص متمّيز يعجز عف بمكغيا بمغاء العرب كفصحاؤىا تمّثل في الجمع بيف الخالص مف سّر المغة كمف البياف كمف الحكمة لياـ منو، كالثاني: أّنو مف قريش التي ىي مف دمحم عميو الصالة كالسالـ ىك أفصح العرب لسببيف : األكؿ : أّنو تكفيق مف هللا تعالى كا أفصح المغات كألينيا . الهوامش : النساء : عتر نكر الديف : في ظالؿ الحديث النبكي، دار اليدى، الجزائر، ص ق ك ، ، ج صححو الترمذي كحسنو ، الترمذي: سنف الترمذي، تح أحمد دمحم شاكر، شركة مصطفى البابي، مصر، ط ، ص ، باب ما جاء في السنة كاجتناب البدع، رقـ: ق ، ص ، ينظر: أبك زىرة دمحم بف دمحم : خاتـ النبييف ملسو هيلع هللا ىلص، دار الفكر العربي، القاىرة، ج ، دت، باب اليمزة مع الداؿ ، ص السيكطي جالؿ الديف: جامع األحاديث، ج المائدة: ، ص ،رقـ الحديث: ابف الحجاج مسمـ: صحيح مسمـ، تح دمحم فؤاد عبد الباقي، دار إحياء التراث العربي، بيركت،ج ق، ص ، ، ج البخاري: صحيح البخاري ، تح دمحم الناصر ناصر، دار طكؽ النجاة، ط ، رقـ الحديث: ق ك ، ، ج دؿ مرشد، مؤسسة الرسالة، طابف حنبل أحمد بف دمحم : مسند اإلماـ أحمد بف حنبل، تح عا ، ص ،ص ، باب في أسمائو ملسو هيلع هللا ىلص ، رقـ الحديث: ابف الحجاج مسمـ: صحيح مسمـ، ج ك ينظر: ابف سكيمـ دمحم بف دمحم: السيرة النبكية عمى ضكء القرآف كالسنة، ص ابف كثير إسماعيل بف عمر: معجزات النبي ملسو هيلع هللا ىلص، د.د ، د.ط ، د.ت ، ص ينظر: ،ص ابف حنبل أحمد بف دمحم : مسند اإلماـ أحمد بف حنبل، ج the secret of the beauty of the speech of the prophet آؿ عمراف: القمـ : ينظر: ابف سكيمـ دمحم بف دمحم: السيرة النبكية عمى ضكء القرآف كالسنة ، ص سبأ : األحزاب : القمـ: المائدة: ك ك ك ك ك ك ينظر: ابف كثير إسماعيل بف عمر: معجزات النبي ملسو هيلع هللا ىلص، ص النساء: ك ينظر: العقاد عباس محمكد : عبقرية دمحم، دار الرحاب ، الجزائر، د.ت ، ص ق ، بف عيسى : الشمائل الدمحمية كالخصائل المصطفكية ، تح سيد بف عباس الجميمي، المكتبة التجارية، مكة، طالترمذي دمحم ، ص ك ، ص ق ك الرافعي مصطفى صادؽ : إعجاز القرآف كالبالغة النبكية، دار الكتاب العربي، بيركت، رآف كالبالغة النبكية، صالرافعي مصطفى صادؽ : إعجاز الق المرجع نفسو ، ص المرجع السابق ، المرجع نفسو ، ص ك ق، ص ، الجاحع : البياف كالتبييف، دار مكتبة اليالؿ ، بيركت، ج ، ص أبك زىرة دمحم بف دمحم : خاتـ النبييف ملسو هيلع هللا ىلص، ج ك ى صادؽ : إعجاز القرآف كالبالغة النبكية ، الرافعي مصطف المرجع نفسو، ص ينظر: العقاد عباس محمكد : عبقرية دمحم، ص المرجع نفسو ، ص ، ص البخاري : صحيح البخاري، ج ، ص ق ك ، الصديق دمحم الصالح : جكامع الكمـ النبكية، دار طميطمة، ط ك النجـ: ، ص ابف الحجاج مسمـ : صحيح مسمـ ، ج مصطفى صادؽ : إعجاز القرآف كالبالغة النبكية ، ص المرجع السابق، ص citation information/kaynakça bilgisi nahmar, f. z. ( the secret of the beauty of the speech of the prophet, jass studies-the jour- nal of academic social science studies, doi number:http://dx.doi.org/ . /jasss , number: autumn i , p. - . - _ecs_ .indd www.ssoar.info the beautiful in the commonplace skatvedt, astrid; schou, kirsten costain postprint / postprint zeitschriftenartikel / journal article zur verfügung gestellt in kooperation mit / provided in cooperation with: www.peerproject.eu empfohlene zitierung / suggested citation: skatvedt, a., & schou, k. c. ( ). the beautiful in the commonplace. european journal of cultural studies, ( ), - . https://doi.org/ . / nutzungsbedingungen: dieser text wird unter dem "peer licence agreement zur verfügung" gestellt. nähere auskünfte zum peer-projekt finden sie hier: http://www.peerproject.eu gewährt wird ein nicht exklusives, nicht übertragbares, persönliches und beschränktes recht auf nutzung dieses dokuments. dieses dokument ist ausschließlich für den persönlichen, nicht-kommerziellen gebrauch bestimmt. auf sämtlichen kopien dieses dokuments müssen alle urheberrechtshinweise und sonstigen hinweise auf gesetzlichen schutz beibehalten werden. sie dürfen dieses dokument nicht in irgendeiner weise abändern, noch dürfen sie dieses dokument für öffentliche oder kommerzielle zwecke vervielfältigen, öffentlich ausstellen, aufführen, vertreiben oder anderweitig nutzen. mit der verwendung dieses dokuments erkennen sie die nutzungsbedingungen an. terms of use: this document is made available under the "peer licence agreement ". for more information regarding the peer-project see: http://www.peerproject.eu this document is solely intended for your personal, non-commercial use.all of the copies of this documents must retain all copyright information and other information regarding legal protection. you are not allowed to alter this document in any way, to copy it for public or commercial purposes, to exhibit the document in public, to perform, distribute or otherwise use the document in public. by using this particular document, you accept the above-stated conditions of use. diese version ist zitierbar unter / this version is citable under: https://nbn-resolving.org/urn:nbn:de: -ssoar- http://www.ssoar.info https://doi.org/ . / http://www.peerproject.eu http://www.peerproject.eu https://nbn-resolving.org/urn:nbn:de: -ssoar-                                             copyright © sage publications los angeles, london, new delhi and singapore vol () – ; - doi: . / www.sagepublications.com        the beautiful in the commonplace astrid skatvedt and kirsten costain schou university of oslo  during fieldwork in a rehabilitation institution for drug abusers, i became aware that certain, apparently commonplace, informal interaction situations between residents and staff appeared to constitute emotionally moving and identity-constructing situations which apparently had a great impact on the residents. these situations seem, on the surface, to be trivial, minor, superficial and very common. still, and perhaps because of their ‘smallness’, they show qualities that suggest authentic interaction, immediate and unfeigned, by participants. this article draws upon an analysis of what i have called ‘love-bearing interaction situations’ (skatvedt, ) and connects this with theoretical insights drawn from the work of erving goffman and johan asplund, and from howard becker’s labelling theory. of particular interest is a notion touched upon by goffman, namely, the expression of love in commonplace interaction.  commonplace interaction, emotions, goffman, identity, labelling, relations, social encounters introduction goffman briefly touches upon the notion of the expression of love in commonplace interaction: these two tendencies, that of the speaker to scale down his expressions and that of the listeners to scale up their interests, each in the light of the other’s capacities and demands, form the bridge that people build to one another, allowing them to meet for a moment of talk in a communion of reciprocally sustained involvement. it is this spark, not the more obvious kinds of love, that lights up the world. (goffman, [ ] : – ) like goffman, i am concerned with the face-to-face situations of everyday life in my fieldwork at the house, a norwegian residential rehabilitation institution for adult drug abusers. i first became aware of the ‘specialness’ of the commonplace when one particular situation had an impact on me. i had had a very heavy, lonely and fruitless day as a researcher in the field,                    studies                               ( ) and my morale was low. i felt invisible and useless. i sat in the living room, messing about with my apparently meaningless field notes. the house was empty, except for tom, one of the residents, who was clearing up the kitchen. all of a sudden he stood in the doorway to the lounge and shouted enthusiastically: ‘hey astrid, i’ve saved the day! i found a bag of coffee when i cleaned behind the freezer!’ i thought that they had run out of coffee and answered politely, ‘ok, that’s good.’ in a place like the house it is important to have enough coffee, and though i was pleased with this news, it was not in itself of particular emotional significance. the impact of the situation came from tom’s use of my name, and he had beamed at me while sharing the satisfaction of his discovery. i had a clear and immediate experience of being made into a ‘somebody’, ‘one of us’, when he addressed me in this way. tom’s interaction with me thus constituted an identity-constructing situation. i, who at that point had felt like ‘nobody’, was touched by being made ‘someone’ to whom it was important to tell something vital. at that moment i began to believe i could achieve something at the house after all. i started to understand the power and magnification of such moments of commonplace contact. i have previously termed interaction situations like this one ‘love-bearing’ (skatvedt, ). i wish to investigate here what characterizes situations like these, and how they can best be understood. this article concerns feelings, but not emotions in the traditional sense. i am concerned with situations that, relatively speaking, are trivial, ap- parently superficial, which occur frequently. still, and perhaps because of their smallness, they show qualities of authentic interaction, immediate and unfeigned. the type of interaction situation in question does not appear as an intimate or expressly loving interaction in the usual sense, that is, as particularly intimate, passionate, private or even necessarily per- sonal. according to the residents, such interaction did not even have to be pleasant; it had to carry what might be called signs of life, the opposite of indifference. with asplund ( : ), we can regard interaction situ- ations like these as illustrations of ‘social responsivity’. as the title of his essay ‘alienation from interaction’ ([ ] ) suggests, goffman writes primarily about rituals of degradation and meetings between people that have a problematic nature. the quotation above is a rare exception from this focus. goffman often highlights the processes and consequences of following or not following implicit rules in interaction. in this article, however, i will emphasize the last three lines of the quotation in examining what might be happening when people meet in such a way that the world lights up for them. i wish to describe the love-bearing interchange as a social phenomenon in everyday life and to suggest a theoretical understanding of situations of this kind. while we are concerned to indicate directions for further analysis and theorizing, the focus of this article will be on empirical material and analysis. it is beyond the scope of this article to argue an elaborate theoretical base.                                             material and method my fieldwork is an ethnographic study which has much in common with the tradition exemplified by goffman’s asylums ( ) from a psychiatric ward in the usa; løchen’s idealer og realiteter [ideals and realities] ( ) from a psychiatric hospital in norway; mathiesen’s the defences of the weak ( ) from a norwegian prison; and album’s nære fremmede [close strangers] ( ), an analysis of patient-to-patient interaction in a norwegian somatic hospital. goffman, løchen and mathiesen have been identified as ‘sociologists of the underdog’. in contrast, and like album, i focus on aspects of the treatment institution and its activities that appear to be affirming and positive. i have taken a phenomenological approach to the field. i seek to present a description of daily life at the house as close as possible to the residents’ own. that is to say, this article is a matter of naturalistic sociology (schatzman and strauss, ). my aim has not been to gather large amounts of quantitative material nor to make comparisons. my wish is to present ‘thick descriptions’ of interaction situations (geertz, ). the data upon which this analysis is based consists of interviews, field note descriptions of both formal and informal interaction and reflective notes about these observations and descriptions. the house is a norwegian state-run rehabilitation institution for people with drug- related addiction problems. it offers a treatment program that runs for one year from admission, with one-and-a-half years of follow-up, for which the county social services is responsible. the residents of the house are male and female, are admitted voluntarily, and had a mean age of years when the fieldwork was carried out. there is accommodation for residents who must be drug-free on admission. most residents have been in a detoxification unit before entry, until they can provide ‘clean’ urine samples. some come directly from prison after finishing their sentences, while some are serving sentences for various offences while resident at the house. most have had contact with rehabilitation units previously and are very experienced both as drug users and as treatment clients. i was a participant observer at the house for a total of one year. i came and went as i wished, living and working with the residents for shorter and longer periods of time. i had my own residential room in which i slept. my job was to perform the same tasks as the newest residents: tidying, cleaning, setting the table for meals, cooking, dishwashing, laundry, gardening, maintenance work on the buildings and so forth. i received my instructions from the resident who was leader of the work team to which i belonged. i took part in organized activities, both formal and informal, such as individual consultations, therapy groups, meetings, recreational trips, parties for friends and family, visits to the movies and so on. the residents and i were together for most of the time we were awake during the day, with our final meeting each day typically in the bathroom, brushing                               ( ) our teeth together. i am confident that this participatory observation was essential to my goal of close contact with the residents. it might be argued that i was in danger of getting too close, of ‘going native’, but the fact that i came and went and had periods away from the field has probably reduced this problem. my study is resident-centred in the sense that i have chosen not to focus on staff members’ perspectives or interpretations or evaluate their activ- ities. this does not mean that i was not aware of the staff’s presence, but i deliberately chose an exclusive focus on the residents instead. while i did on occasion have brief chats with staff members, a resident was always present. it has been important for me to keep a significant distance from the staff culture, as staff members function as both therapists and guards. i wanted to come as close to the resident world as possible, and distance between the staff and myself was necessary for this. the limitation is that i did not access staff members’ points of view. to my knowledge, the staff did not perceive this as unfair. rather, they seemed profoundly interested in the knowledge that research like this could give them. it seemed essential for the residents that i had a clearly defined role as a non-staff member and as a participant on a resident level, with the distinction that i had different goals for my stay from those of the other residents. ‘c‘mere!! i need somebody for the dishes! … heh heh, no no! i was only kidding!’ was the first comment i received when i arrived to start my fieldwork. the residents expressed great surprise at the fact that i wanted to be only with them. they would have been less surprised at this had i been younger (i was in my forties during the fieldwork); apparently i had broken with the residents’ expectations of what women my age do (or do not do). i believe that this breach was one reason i easily obtained their permission to enter their world and was considered trustworthy. it seems clear to me that my insights into the ‘moving’ aspects of daily life at the house were possible because i lived and worked solely with the residents over time. they were the ones from whom i needed recognition, both in order to ‘get inside’ the house and to avoid becoming isolated in the field. because i was neither staff nor resident, and there were no other researchers present, i had in a way a meagre identity at the house. tom had made it richer in a moment by calling to me when he found the bag of coffee. empirical material like this is difficult to structure into manageable categories. quite early on, i started to systematize data through a counting method. i went through the data in order to find out which types of situ- ations the residents talked most about when they spoke about ‘good’ situations, and what characterized them. the concepts i have used are a mixture of the residents’ language of description and my own inter- pretations of what i heard and saw, with care taken to preserve the informal language of each. i ended up with different ‘good’ interaction                                             forms between residents and staff. these were gathered into three types of situations: emotionally loaded situations, personal situations and com- monplace situations (see appendix). they have different principal features and are not mutually exclusive categories. the fact that they have features in common, e.g. ‘good’ and ‘everyday’, made it a challenge to make the implicit particularities explicit. client-centred research during the last decade there has been increasing interest in clients’ theories of change. there are many substantial contributions, such as duncan and miller’s the heroic client ( ) and the heart and soul of change edited by hubble et al. ( ), which presents analyses of the extensive literature on working elements in therapy. their attention is to common factors shared by all therapy orientations. according to asay and lambert ( ), the therapeutic relationship and extra-therapeutic events are two common factors that together count for percent of im- provement in psychotherapy. therapeutic technique accounts for only percent. this literature seeks to present a client-theory approach. i agree about the importance of this approach, though i find it too expert-centric. the studies i refer to above seem to have one feature in common: data on clients’ theories of change is, to a large extent, collected on the expert’s premises, from the expert’s perspective, in his or her office, using cat- egories stemming from the expert. this type of data reflects to a lesser extent the client-world and the client’s categories, conceptions, beliefs and understanding. the ‘client-centred knowledge’ produced is, so to speak, ‘therapist-oriented’ – it comes from above. hubble et al. ( ) have made important contributions to the search for clients’ theories. but their knowledge rests on a powerful clinical understanding of where and how we can get insights into processes of change. glen gabbard ( : ) writes that a tremendous amount of research shows that psychotherapy has value within the psychiatric field. however, when it comes to understanding how it works, we know very little. he writes that when psychotherapists ask their patients about what has been helpful, the patient’s fondest memory may be a joke that the therapist told, and not his or her brilliant therapeutic technique. he points to the lack of data illustrating the active aspects of the therapeutic endeavour and presents a new article (høglend et al., ) in which the authors conclude that the establishment of a good treatment relationship can be an active ingredient in psychotherapy. these studies must be said to be very different from my own: they are quantitative and medically oriented and concern patients who are, it must be said, more ill upon admission to therapy than are the residents of the house. however, høglend et al. do direct their attention similarly toward the treatment relationship and patients’ perspectives on it.                               ( ) rich ordinarinesses ordinary everyday interaction, despite its mundane nature, can be ‘moving’, emotionally and psychologically, and can enable those involved to reach another, preferably better, place in their biography by changing existing or adding new narratives or stories about themselves. in addition, such interaction constitutes the majority of face-to-face interactions that people have in the course of most days. institutions like the house represent a society in miniature where social life is pared down to its essential elements. social interaction at the house took place in frames that were readily accessible to the researcher. the residents appeared to be very conscious and attentive observers. they were good at catching what was going on in different situations and between different persons with what might be viewed as over-sensitivity to subtle signals and cues. most residents had extensive experience as substance abusers and therapeutic clients, and were probably especially observant because this had been a necessary skill in order for them to function ‘outside’. as one resident remarked: you know, you do have to have reasonably good antennae to catch moods and what’s in the air and … of course we see, we’re experts in seeing, under- standing how people think, how they feel and all – we’ve had to be! this skill is probably connected to the fact that the activity they have in common is illegal. they cannot be straightforward in approaching other people, in order to get the next ‘fix’, unless they are sure about who they are. the residents often made jokes about being able to spot the police, a social worker, a childcare employee or a drug addict from a distance, no matter where they were. those who were good at observing people and their possible intentions usually seemed to have been good at staying out of trouble with the authorities. finding meaning in the social and cultural context of the house was more of a challenge for residents, as it was a very different context from those with which they had usually been familiar. one tendency i noted was for residents to fix upon, and express being strongly moved by, features of normal interaction that others might take for granted. this might have something to do with the residents having what might be called ‘meagre identities’ or ‘fragile selves’ (album, ). the residents have had to abandon most of their identity in the world outside as part of their work on change. they are, in a sense, in search of something or somebody who can tell them ‘who they are’. i favour a concept of identity similar to that sketched by goffman ([ ] : ) when he writes that ‘the individual must rely on others to complete the picture of him of which he himself is allowed to paint only certain parts’. the self is understood here as a dynamic phenomenon that emerges and develops through self- reflection and in cooperation with important others. according to the residents, the staff are these significant others. the residents seemed so                                             hungry for identity signs that they fixed attention even on non-noteworthy elements of interactions, looking for signs that reflected back to them that they were more than undignified ‘junkies’. goffman ([ ] ) writes about the self as both one’s own product, in the sense that we choose how we present ourselves to others, and also as a result of interaction with others, during which we receive symbolic messages or signs about who we are. this idea fits well with the ‘counter’ labelling process which i will introduce here. in a similar sense to durkheim ( ), goffman views the self as a sacred object, but for him, selves are acknowledged as ‘holy’ through innumerable small and everyday interaction situations. this makes everyday interchange (such as that between staff and residents) into symbolic interaction with the distinction of ritual. according to goffman ([ ] ), we have a tendency to use and adopt signs that mediate messages about selves and expose who we are. this implies, as mentioned above, that communi- cation between people is communication about identity. good labellings and troublesome labellings goffman develops cooley’s ( ) and mead’s ( ) ideas about the self as product of social interaction, and there are similarities between goffman ( , ) and becker ( ) in this regard. both have common roots in cooley and mead: mead’s ( ) writings about the self suggest a notion of labelling, in that the individual becomes a human being by ‘seeing one’s self through others’ eyes’. all four have developed models of socialization. cooley and mead write about how selves are created through primary socialization, whereas becker and goffman present the self as a result of secondary socialization, although becker is more of a relationist where goffman is a situationist. both understand the self as manifold; it can be created and recreated, and resocialized. asplund ( ), to whom i will return later, can also be said to espouse a socializing model. becker’s ( ) labelling theory is thus attached to an interactionist tradition and is frequently used as a perspective on deviance and deviants as social constructions. according to becker, a deviant is ‘one to whom that label has successfully been applied’ ( : ). drug users are easily labelled deviants in this sense. becker declares deviance a consequence of the response of others. a person has become the label when he or she has integrated the identity that is attached to that label and made it his or her own. becker writes about how one becomes an outsider, whereas our focus is on how one becomes an insider. we see this as the same labelling process, but as ‘counter’, in that it has an opposite and ‘positive’ development. we are concerned with becker’s understanding of labelling as process. individuals are assigned identity tags that are visible and clear, both for the bearer and for their social milieu. we use only a small aspect                               ( ) of becker’s theory on deviance and deviants as social constructions; this is not a critique of his ideas but rather a use of them in inverted form. according to the residents, the staff appeared as significant others in each resident’s identity project. it was the staff who were authorized as labellers and who could declare residents, over and over again, as ‘insiders’. instead of sanctions that declare deviant identities, as in becker, the residents describe being confirmed as ordinary people. the ‘label’ of what appears to be the residents’ own labelling theory declared ‘you are one of us’ (normal, worthy). the labelling process took place during infor- mal interaction, in which powerful signs of new, alternative selves were mediated and which gradually accumulated and became ‘fixed’, thereby beginning to take on the character of permanence. we view all interaction as rich in meaning, in the sense that interaction mediates symbolic messages about selves, about who we are. the messages or signs conveyed are interpreted by the receiver in different contexts. goffman ([ ] : ) writes that: ‘the gestures which we sometimes call empty are perhaps in fact the fullest things of all.’ excerpts from residents’ stories presented below are illustrations of such rich emptinesses, full of meaning: valuable situations that appear insignificant at first glance. as we shall see, even the slightest hint of recognition of one’s own presence was described as conveying messages about one’s worth. knut (a resident) said about one of the staff who often invited him for a cigarette on the ‘smoking porch’: she seems to enjoy chatting with me … ‘come here! now we’re going to have a cigarette,’ she says! … she apparently enjoys chatting with me … so nice, eh! from a staff member, you know! the staff member could easily have smoked her cigarette elsewhere, either by herself in peace and quiet, or with a colleague. knut was made into the sort of person she could enjoy having a cigarette with, and he indicated receiving a message about being ‘the same kind of person’ as the others – normal and worthy people. this can be regarded as a feature of a ‘counter’ labelling process, which takes place again and again in the course of ordinary interaction. goffman ([ ] ) writes as if the right and proper thing is when interaction follows a pattern that is more or less fixed. but in my empir- ical material it becomes apparent that interaction can also be successful (and beautiful) by breaching or challenging unspoken norms, rules and expectations about how it is supposed to be enacted. messages beyond the spoken every morning the residents and i sat on the smoking porch. it was at that time the staff arrived for work. one day, harald, the manager of the house, approached us. he greeted us and looked very amused and                                             self-satisfied. he put his bag down beside him, leaned against the rail opposite kjell and terje, who sat on a bench, and lit his cigarette. he was more formally dressed than usual. kjell looked at him with a curious glance and said, ‘you’re really dressed up, harald, are you going on a visit today?’ harald answered, ‘i am receiving a visit today – i’m going to have a meeting with the guys who make decisions about residents’ funding. clothes do have a lot to say when it comes to what one can achieve,’ as he leant towards kjell, smiled and squinted his eyes. they laughed at this and i didn’t understand what was so funny. this exchange illustrates what i call ‘an advanced sign of affection’ – ‘teasing’ – something which is not immediately recognizable as a sign of love, and often takes a rough form, but declares the situational equality of those involved. harald gives signs to the residents that tell them they are included in an area of his private sphere, and that they are significant – for example, indicating he had thought of them that morning while he got dressed. the fact of his dressing up for the meeting holds a different meaning than if he had merely read some papers in order to prepare for the same meeting. the residents receive confirmation that they have left an impression on harald. the relational proximity between them is reflected in the atmosphere of the interaction, which is characterized by humour, warmth and reciprocity. they stand close to each other, they look at each other, chuckle and exchange glances; they gesticulate, light each others’ cigarettes and fetch cups of coffee for each other. harald could have had his cigarette elsewhere and hurried into his office after a short ‘hi!’, but he remained outside instead, ‘without reason’. the residents indicated appreciation for this, and it was probably a good experience to be someone with whom the boss wanted to chat and smoke. ‘i hear him talk to us the same way he talks to everybody else,’ john said. in spite of the casualness and apparent superficiality of situations like this, they become incidents that hold great significance. these situations are understood as a break with the expected and with the formal social positions of the house. harald’s participation appears authentic and not as a manifestation of his duty. this helps the messages communicated about the selves involved to become valid as ‘good labels’. in this way we can say that a labelling process is triggered and maintained with the reverse direction of development from that seen in becker ( ) – a median labelling, in which residents tend to adopt the self ascribed by significant others, making it their own. i emphasize here that the question of whether this was intended or ‘really felt’ and ‘authentic’ from the staff member’s side is irrelevant; we cannot know this – the important point is that the residents interpret it as such. those who enter the dining room at the house during mealtimes will usually see that staff sit at one table, while residents sit at the others. the atmosphere may vary greatly, from quiet gloominess to hilarious noisiness. it is not usual to discuss personal issues or emotions. ideally,                               ( ) mealtime conversation should concern everyday matters, preferably those that are minimally ‘loaded’. martin, a resident, told me about what siri (a staff member) had said during a short meeting over lunch. a break arose from the usual lunch-frame, and the situation changed character for a moment: like she … siri, when she came over to me during lunch and said that … eehh … after i had a relapse and … i had some big trouble i hadn’t sorted out yet, then she said, ‘i’ve been thinking a lot about you’ … when she says things like that a couple of times, it … i remember it … like, i see the picture in my head … then she stood in front of me, by the coffee machine, pouring coffee and looking at me and then she said it … and then she looked at me, and then she meant it, she did! when things like that get you in the stomach … ooohh … yes … it goes in, you know! … yes. this meeting had taken place a long time prior to our discussing it, but martin was still clearly touched when relating it and remembering it. we may say that siri had distinguished a footing, a footing of intimacy, from that of the usual lunch-frame. goffman ( : ) introduces this notion in forms of talk, suggesting the power of breaks in interaction in which a new ‘micro-frame’ suddenly appears in the frame. he explicates his definition of ‘footing’ in a story about an article in a newspaper in : president nixon signing a bill in the presence of government officers and newspaper reporters in the oval office. after the ceremony, he rises and comments, in a teasing way, on the outfit and looks of one of the female journalists. he calls her by her name, uses a cheerful voice, and even gets her to turn around so that everybody can see how nice she looks ‘in spite of ’ her wearing trousers, all of which results in much merriment amongst the press corps and others present, including the woman herself. like frames, footings are culturally defined entities with which participants in social life are familiar and which they can use. small signs might put forward a new situation: a gaze, a change of attention or a special tone of voice. this is what happens in the lunch story, and what contributes emotional force – a sudden break with the predictable flow of events. the concept of footing can be used both for describing a degrading situation for the self and a situation that might be positively magnifying. both appear as emotionally moving for the one who is the focus of the shift. it is the breach and the emotional dimension that make the communicated sign ‘hit home’ and ‘work’, both for martin and for the journalist and press corps in the nixon example. we can say the same about the other examples: tom’s discovery of the coffee-bag, harald and kjell’s talk by the stairs and the staff member’s invitation to smoke. if the participants in these situations had not been moved by them in each case, they would have barely registered them, as they would not have had any real significance. in the meeting by the coffee machine it is not goffmanian rules for good or expected conduct that make the situation become special; rather,                                             it is the violation of such rules. martin says that siri meant what she said. objectively speaking, he cannot know anything about this. however, the point is that martin describes experiencing her behaviour as genuine. it is the registration of breaches, of siri’s and his own emotional reactions, of siri’s gaze, body language, tone of voice, strength of voice that make martin draw his conclusion about authenticity in the situation. another resident, john, describes another encounter with a staff member: ‘it’s just there … like … i just feel it, i notice it when he talks with me, like … that it’s not something he says just because it’s his job.’ the residents’ ‘feeling’ is interpreted as a sign of authenticity in the interaction. in both the white house situation and during lunch hour by the coffee machine, a high-status participant transforms one of lower status into a specific somebody: nixon changes the journalist from a competent reporter into a sweet and naughty, slightly stupid girl at whom everybody laughs. martin goes from being one of many ‘hopeless junkies’ to someone with significant meaning for a staff member. both are apparently moved, but in opposite directions. the stories are illustrations of what asplund ( : ) describes as ‘social responsivity’, which can be both light and dark; the socially responsive human being can be both appealing, as with siri, or offensive, as in nixon’s case. sanctifying discourtesy martin related a fishing trip that he had taken with sivert (a staff member) one day, when sivert had his day off. martin had been a resident long enough to have permission to leave the premises on his own. the fishing spot was near his home. they had planned to be away all day but had forgotten to bring food. martin suggested they could eat something at his place: he wanted to come fishing with me! on his day off! he came with me to my place, and the way he was at home with me and … i asked him in for some hot dogs and coffee and things like that, and he was there, it was … like … he behaved … it was so okay! [martin laughs as he tells me] … he wasn’t there with a strict face on … like … ‘here is a staff member’ … you know … he was just … ‘hey, shall we eat soon, or what?’ … he was so very okay, it was just like being with a pal … i thought it was so good that … i noticed i was different that day there, when we were together. it is unusual for staff to join clients in activities outside of working hours, and it is generally frowned upon to do so, though i shall not discuss that here. a staff member’s wish to participate in something with a resident without ‘having to do it’ might in itself be a powerful sign of sameness. sivert’s comments about when they were to eat were apparently what made the biggest impression on martin, and where we find the emotional dimension of the anecdote. it is not very polite to ask, ‘hey, shall we eat soon, or what?’ when one is a guest. it is as if martin highlights the closeness                               ( ) of the situation through his brusque question. friendship and intimacy can be declared through rudeness (album, ). two persons who do not know each other would be unlikely to raise the question of eating at the other’s place, as this could easily be interpreted as presumptuous or inappropriate. at the very least, such an inquiry should have been properly framed in a politely formal manner. pals can be bad mannered toward one other. it might even be necessary in ‘pal-hood’. martin obviously has experience of such friendship, enabling him to interpret sivert’s question as a declaration of intimacy. we might say that the two of them speak in a goffmanesque way: they follow the rules of pal-talk. but martin and sivert are not pals in the ordinary sense; they are client and therapist. sivert’s question represents a break with expected ‘professional’ behaviour. in this breach, the goffmanian ‘bridge’ is established between them, and they become alike – of the same kind – even if it is for just a moment. martin receives definition as one worthy of pal-hood from one with the authorization to bestow it. he can acquire a self as an ordinary man through this ‘counter’ labelling process. without the breaches i have highlighted, the fishing tour would have been qualitatively different, and potential signs of equality would not have had the same validity. the fishing trip lasted several hours – they had quite possibly talked a great deal of therapy-talk – for instance, men’s group talk. but the comment ‘hey, shall we eat soon, or what?’ is what martin presents as particularly important. goffman ([ ] : – ) writes about the profanation of selves through the use of humiliating talk or other means of degradation. the example of rudeness during the fishing trip illustrates instead how a profaned self (the deviant drug abuser) can be made ‘sacred’, or worthy. martin is declared as similar to the other and thereby also as worthy. he receives a self distinct from the one he usually has at the house. norms of interaction between staff and clients will, in contrast, often serve the client self (the less worthy self) as the sacred self. for instance, staff members may, with good intentions, present ‘over-involvement’ (goffman, [ ] : ) in interaction with clients. some might, unwillingly, force in- timacy upon clients by using their given name too often and sometimes at the wrong occasion or in the wrong tone of voice. the opposite is nicely illustrated by the resident who told me that he heard that the leader of the house talks to him in the same way that he talks to everybody else (while pointing at the staff members). in this way, distance between people and differences in levels of worthiness are marked through norms of behaviour. during the fishing trip, martin is identified as competent, sober and normal; however, he cannot confirm such an identity on his own. neither can the other residents. this must be done by powerful representatives of the others, such as staff members. in the example of the fishing trip, it is rudeness and the apparently immediate ease that raises the interaction. sivert, who has the power of                                             definition in the situation, breaches the norm-confirmed therapy frame. this is also what happens, though more poetically, in the lunch meeting between martin and siri. the fishing trip is prosaic by comparison; it is easier to see the coffee-machine meeting as a beautiful situation, some- thing that can light up the resident’s life. there, the sanctifying of the self does not occur through rudeness, but is still a breach of rules governing staff behaviour. these situations appear as identity-construing situations or footings, as links in what i see as a ‘counter’ or more ‘initial’ labelling process. it is not what at first appears beautiful or poetic that is the essence of these stories; it is that something greater than the objective quality of the interchange occurs with the sudden breach in the rules of interaction. this suddenness and immediacy make the meta-message of the interaction authentic – it is instantly believable: ‘it goes in, it sticks’, as knut said. it is as if the residents’ own emotional reactions – that they feel moved – contribute to their interpretation of what is said to be true. then it is no longer relevant to reflect on whether the other could have meant it or not: ‘i just feel it’, as john said. the experience of being moved has a logic of its own: ‘i’m moved, ergo what was said is true.’ these situations appear to transport the resident to another emotional and psychological position in his or her biography. according to the residents, situations like these had a powerful therapeutic potential in enabling them to believe in themselves, by giving hope that they could cope with ‘the work’ they had to do in order to live a drug-free life. if we return to the goffman quotation in the introduction, goffman’s point is that the speakers should do the speaking in the ‘right’ way so that the world is ‘lit up’. one might ask whether it is sufficient merely to ‘do it right’, in that each participant adjusts ‘correctly’ in relation to the other. another question is whether norms, implicit or explicit, might hinder the experience of interaction as an expression of love. it is as much the breaching of the norms that regulate interaction between staff and client that seems to comprise the emotional force in the situations i have presented. rules and breaches in the elementary forms of social life (authors’ translation), asplund ( ) has written about people’s alienation from each other when role reasoning characterizes the relation between them. asplund’s role concept is applied to relations characterized by distance, in which participants are established as distinct from one another. he claims that such relations are characterized by an abstract sociality in which one participant sees the other as an abstract member of society and not as a concrete person (asplund, : – ). according to asplund, this distancing is characteristic of many professional arenas, including care professions such as social work and psychotherapy.                               ( ) abstract sociality is the antonym of the social responsivity mentioned above, in which participants take turns in responding to each other’s ini- tiatives. in social responsivity, people reverberate with one another, they move and are moved, the opposite of indifference and pretence. social responsivity demands liberation from rules and formalized action. it demands immediacy: ‘a social responsivity that is reined and formalized can no longer be regarded as social responsivity. interaction that unswervingly follows a protocol is of course not informal behaviour. social responsivity is characterized by breaches of rules and improvisations’ (asplund : – ). here, asplund isolates a norm for social responsivity – that it must be immediate. both asplund and goffman refer to the norm of spontaneity, and it would appear that the residents’ own theories of interaction are similar in this respect. the point is not whether what goes on is ‘good’, but that there are response and reciprocation which are not exposed as pretence. immediacy is necessary for authenticity. if it is lacking, the interaction turns into asocial irresponsiveness and it cannot ‘move’. in asocial irresponsiveness, people see each other as ‘abstract societal beings’, or as asplundian ‘role-occupants’. according to the residents, the emotional power of their anecdotes is such that they still feel moved in remembering and relating them. the intimations of identity they received from staff members in these inter- actions have an effect that far exceeds the interactions themselves. here, they are in agreement with goffman; one must receive such signs from significant others, people who have the power to declare a resident’s iden- tity. in addition, such signs must be mediated in encounters characterized by the spiritual and emotional presence of staff members. this seems to occur most visibly and reliably in everyday interactions in which powerful, identity-constructing messages are conveyed and accumulate to form a new biography for each resident. such episodes will form part of a continuum in the project of the reflective self (giddens, ). the residents – societal deviants – become labelled ‘ordinary’ people. in my analysis of residents’ reflections on significant interactions with staff, it is precisely commonplaceness and immediacy that come into view as important conditions in the process of acquiring an identity as sober. the commonplace interactions we take part in seem to give us particularly reliable signs of who we are, and they can have greater potential in establishing or labelling worthy identities than more formal interaction situations. the special in the commonplace we have seen that everyday interactions are situations in which the self can be acknowledged as sacred and can emerge as worthy, even in situations that are quite profane. one of the findings of the fieldwork is that commonplace interactions between staff and residents seem to have                                             potential to contribute to new resident narratives. here, where there is no express therapeutic value, staff and residents can move and be moved and can meet in reciprocity. they can regard each other as what asplund ( ) calls concrete persons – not as abstract members of society: ‘abstract members of society can neither love nor be loved, neither hate nor be hated. one cannot empathize with them, be compassionate with them, pity them, etc. there is nothing to love, hate, be compassionate about or pity’ (asplund, : ). we understand asplund to claim that human beings are comprised of both an abstract and a concrete aspect. the concrete is the human being of flesh and blood, the one that can be moved and can move in an emotional sense. the abstract individual, on the other hand, houses the role, really a copy of one’s self – an abstraction – that can be loved only in an iconic sense, and which can neither move nor be moved by others (asplund, ). in this perspective, both drug abusers undergoing treatment and staff members can appear to each other as abstract individuals – as occupants of the role of client or staff member. it is often regarded as ideal to take on different professional roles. however, from an asplundian perspective, such roles might contribute to the establishment of an abstract sociality at the house, a form of lack of contact. the ordinary, everyday interaction both at the house and ‘outside’, between residents and staff members or others, seems to loosen roles and prepare the ground for situations in which people can meet as concrete persons, where one can love and be loved. here, one might say with asplund ( : – ), the participants are enacting social responsivity, ‘an elementary form of social life’. the introductory citation in this article is taken from interaction ritual (goffman, [ ] ). contained in goffman’s title is the concept of ‘ritual’, and in asplund ( ) is the concept ‘elementary’. rituals are not elementary in the sense of being fundamental or pre-meditated in the same way that the elementary is. rituals tend to be more managed and rule-based than elementary; they are perhaps a rather formalized further development of elementary forms of social life. it appears that breaches of rules of conduct make the participants return to the ‘elementary’. they fall out of the rule-based situation, not into nothingness, but into a situation that cuts across rules. it is as if some situations have moments of liberating emptiness in which the echo of authenticity can be heard. perhaps such a ‘clean’ sociality (asplund, ) is a basic human property, where participants are subjects for each other, or where they are ‘just humans together’, as one of the residents said with emphasis. the fieldwork took place in an institution characterized in part by thera- peutic relations. such relations are norm-laden and governed by rules, limiting the possibilities for staff and clients to relate as concrete persons in an asplundian sense. while we do not wish to flout the importance of professional ethics of engagement, it is perhaps the case that formalizing interaction also can contribute to distance and alienation between                               ( ) participants. the empirical material gives voice to the converse need for immediacy and authenticity in such interaction. notes . the pronoun ‘i’ is used in the beginning of this article. later on we use ‘we’. the ‘i’ refers to the first author’s specific experience of the fieldwork that led to the master’s thesis stories of love (skatvedt, ). . the article is a revised and developed version of an article published in norwegian in (skatvedt, ) in the journal sosiologi i dag [sociology today], presenting erving goffman’s writings in a themed issue. . the fieldwork was conducted in connection with stories of love and also the first author’s doctoral project, the potential of the commonplace. the doctoral project is financed by the norwegian research council and the university of oslo, and will be completed in spring . . ‘formal’ refers to interaction with a declared therapeutic value, such as individual or group therapy sessions with staff. ‘informal’ refers to interaction without declared therapeutic value, such as a resident and staff member having a cigarette together or shopping in the local supermarket. . all grammatical irregularities in the original transcribed text have been retained. the second author is a native english speaker who has lived in norway for years and has translated from the norwegian with a view to retaining the vernacular and immediacy of the original speech. . we have not tried to understand how the staff experience or interpret the situations in question. the focus has been the residents’ interpretations, and not whether these are reflected in the staff’s understandings. however, we have no reason to believe that the staff’s understandings of the situations are fundamentally different from the residents’. references album, d. ( ) ‘hvordan går det med goffman og garfinkel? teorier om samhandling ansikt til ansikt’ [how is it going with goffman and garfinkel? theories of face-to-face interaction], sosiologisk tidsskrift : – . album, d. ( ) nære fremmede. pasientkulturen i sykehus [close strangers: patient culture in the hospital]. oslo: tano. asay, t.p. and m.j. lambert ( ) ‘the empirical case for the common factors in therapy: quantitative findings’, in m.a hubble, b.l. duncan and s.d. miller (eds) the heart and soul of change: what works in therapy, pp. – . washington, dc: american psychological association. asplund, j. ( ) det sociala livets elementära former [elementary forms of social life]. gøteborg: bokforlaget korpen. becker, h. ( ) outsiders: studies in the sociology of deviance. new york: the free press/simon & schuster inc. cooley, c.h. ( ) human nature and the social order. new york: charles scribner’s sons. duncan, b. and s. miller ( ) the heroic client: doing client-directed, outcome-informed therapy. san francisco, ca: jossey bass. durkheim, e. ( ) the elementary forms of the religious life. new york: the free press.                                             gabbard, g. ( ) ‘when is transference work useful in dynamic psychotherapy?’ american journal of psychiatry : – . geertz, c. ( ) the interpretation of cultures: selected essays. new york: basic books. giddens, a. ( ) modernity and self-identity: self and society in the late modern age. cambridge: polity press. goffman, e. ( ): asylums: essays on the social situation of mental patients and other inmates. new york: first anchor books. goffman, e. ( ) behaviour in public places: notes on the social organization of gatherings. new york: free press. goffman, e. ( ) forms of talk. philadelphia: university of pennsylvania press. goffman, e. ([ ] ) interaction ritual. essays on face-to-face behaviour. new york: pantheon books. goffman, e. ( ) the presentation of self in everyday life. london: penguin books. høglend, p., s. amlo, a. marble, k.-p. bogwald, o. sorbye, m. sjaastad et al. ( ) ‘analysis of the patient–therapist relationship in dynamic psychotherapy: an experimental study of transference interpretations’, american journal of psychiatry : – . hubble, m.a., b.l. duncan and s.d. miller (eds) ( ) the heart and soul of change: what works in therapy. washington, dc: american psychological association. løchen, y. ( ) idealer og realiteter i et psykiatrisk sykehus [ideals and realities in a psychiatric hospital]. oslo: universitetsforlaget. mathiesen, t. ( ) the defences of the weak. a sociological study of a norwegian correctional institution. london: tavistock. mead, g.h. ( ) mind, self and society from the standpoint of a social behaviorist. chicago, il: the university of chicago press. schatzman, l. and a.l. strauss ( ) field research: strategies for a natural sociology. englewood cliffs, nj: prentice hall. skatvedt, a. ( ) ‘fortellinger om kjærlighet. om kommunikasjon mellom ansatte og klienter på en institusjon for stoffmisbrukere’ [‘stories of love. on communication between staff and clients in an institution for drug abusers’], master’s thesis, department of sociology and human geography, university of oslo. skatvedt, a. ( ) ‘det vakre i det alminnelige’ [‘the beautiful in the commonplace’] sosiologi i dag ( ): – . biographical note astrid skatvedt obtained her master’s degree in sociology at the university of oslo in . she is now a phd student, and her project is financed by the norwegian research council. she works at the school of sociology and social geography, university of oslo. her research interests include micro sociology, deviance, drug abuse and treatment, fieldwork and participatory observation. a d d r e s s : school of sociology and human geography, university of oslo, pb blindern, no- oslo, norway. [email: astrid.skatvedt@sosiologi.uio.no]                               ( ) kirsten costain schou obtained her phd in psychology at the university of leeds in . she lives in norway and has held teaching posts at the university of bergen and at diakonhjemmet university college in oslo. her research interests include qualitative methodology, sociological perspectives in quality of life and chronic illness, and palliative care. appendix i have categorized the three types of situation by selecting situations referred to by residents as illustrations of love-bearing togetherness. the formulations below are the residents’ own. i have chosen to present them with the prefix ‘that the staff …’ in order to regularize them. they are presented in the order in which they arose and in point form: . that the staff are personally engaged. . that the staff are together with us. . that the staff show their feelings. . that the staff’s initiatives/topics of talk are of a private nature. . that the talk is non-therapeutic. . that residents feel their own emotional reactions. . that the staff are outside their staff role, and are ‘just people’. . that the staff talk to us as, or treat us as, ordinary people. . that we know the staff think about us. . that the staff talk, or are, like us. . that the staff participate in informal talk there and then. . that staff listen and follow along. . that the staff ask us for advice. . that the staff are honest and fair. . that the staff are understanding. . that the staff say something about me. . that the staff give a hug or a clap on the shoulder. . that we can be one-on-one with staff. . that the staff show hope and optimism. . that the staff show a sense of humour. . that the staff participate in ceremonies. i defined criteria from the types of situation: . personal engagement . emotional expression by staff . own emotional reactions of residents . the private nature of talk and address from the staff . the staff were ‘ordinary people’ . staff had thought about the residents outside of work time . everyday, non-therapeutic talk . staff and residents are together outside of the office . residents are talked to like normal people of these, the first three illustrate the emotionally laden situations. the next three illustrate personal situations. the everyday situations are illustrated in the final three situational types. _ _ _ _ -web .. small is beautiful: why profundaplasty should not be forgotten h. savolainen Æ a. hansen Æ n. diehm Æ i. baumgartner Æ f. dick Æ g. heller Æ b. gahl Æ j. schmidli published online: july � société internationale de chirurgie abstract background surgical profundaplasty (sp)is used mainly as an adjunct to endovascular management of peripheral vascular disease (pad) today. results from earlier series of profundaplasty alone have been controversial, especially regarding its hemodynamic effect. the question is: can profundaplasty alone still be useful? our aim was to evaluate its role in the modern management of vascular patients. methods this was a retrospective outcome study. a consecutive series of patients ( legs) from january through december were included. in ( %) legs, the superficial femoral artery was occluded. these patients were included in the current analysis. of these patients ( %) were female. mean age was (( ) years. nineteen ( %) were diabetic. the indication for operation was claudication in ( %), critical leg ischemia (cli) in ( %), either with rest pain in ( %), or ulcer/gangrene in ( %). endarterectomy with patch angioplasty with bovine pericardium was performed in all cases. mean follow-up was ( months. mean preoperative ankle brachial index (abi) was . . sustained clinical efficacy was defined as upward shift of or greater on the rutherford scale without repeat target limb revas- cularization (tlr) or amputation. mortality, morbidity, need for tlr, or amputation were separate endpoints. results postoperatively, abi was significantly improved (mean = . ), in ( %) by more than . . at three years, cumulative clinical success rate was %. overall, patients with claudication had a better outcome than those with cli (p = . ). two ( %) major amputations and ( %) minor ones were performed, all in patients with cli. none of the ( %) ulcers healed. conclusion profundaplasty is still a valuable option for patients with femoral pad and claudication without tissue loss. it is a straightforward procedure that combines good efficacy with low complication rates. further endovascular treatment may be facilitated. it is not useful for patients with the combination of critical ischemia and tissue loss. since the introduction of distal surgical revascularization and later catheter-based management, surgical profun- daplasty is not commonly performed anymore. results from earlier clinical series have been controversial. in a recent review, earnshaw [ ] concluded: ‘‘there is little literature and no science to provide clear recommendations for profunda disease. indeed, the transatlantic inter- society consensus has nothing to say on the subject.’’ calcified femoral arterial bifurcation is not readily acces- sible for the interventionalist either. a profundaplasty is a straightforward procedure with low morbidity and short hospital stay. does it have any role at all in vascular sur- gery, or should it simply become part of medical history? the aim of our study was to clarify the outcome following open surgical profundaplasty in modern practice. methods between january and december , profun- daplasties were performed in patients at the swiss cardiovascular center (scvc) in berne, switzerland. of the patients, ( %) were female. mean age was h. savolainen (&) � a. hansen � n. diehm � i. baumgartner � f. dick � g. heller � b. gahl � j. schmidli swiss cardiovascular center, university hospital, berne, switzerland e-mail: hannu.savolainen@insel.ch world j surg ( ) : – doi . /s - - -y (± ) years.the superficial femoral artery (sfa) was oc- cluded in ( %) cases. these patients were included in the study. patient charts were retrospectively reviewed. patient characteristics are seen in table . indication for operation was lifestyle-limiting claudica- tion in ( %) and cli in ( %) patients, of which ( %) had ulcer or tissue loss. preoperative duplex scan and angiography were obtained. mean preoperative abi was . . patient selection criteria included ( ) severe stenosis of femoral bifurcation, especially of common and proximal profunda femoris artery with occlusion of the superficial femoral artery, ( ) adequate proximal inflow or inflow to be improved by pta/stenting, and ( ) collaterals seen in angiography. tibial runoff was not an exclusion criteria. the operations were performed as primary surgical reconstruction. previous pta and/or stenting had been performed times in ( %) patients (iliac artery , common femoral , superficial femoral , profunda fem- oris , popliteal times). profundaplasty was performed as previously described by martin et al. [ ]. arterial closure was done using bovine pericardial patch (vascu-guard, synovis life technologies inc., st paul, mn) in all cases. mean (±sd) follow-up was (± . ) months. sustained clinical treatment efficacy was defined as an upward shift of one or more on the rutherford scale [ ] without repeat target limb revascularization (tlr) or amputation. mor- tality, need of amputation, or repeat tlr were solitary study endpoints. cumulative freedom from surgical rein- tervention was defined as freedom from minor or major amputation or arterial reconstruction. subgroup analysis was performed for fontaine stages, for isolated (ip) or combined (ip with pta or stenting) procedure, and dia- betes mellitus. ankle brachial pressure index (abpi) was measured at baseline and postoperatively at intervals. all patients were followed up in the department of angiology at the scvc. statistical analysis statistical analysis was performed using spss software (spss inc., chicago, il). preoperative factors predicting successful outcome were analyzed using fischer’s exact test. kaplan–meier survival analysis was used to estimate the rates of cumulative freedom from surgical reinterven- tion and sustained clinical treatment efficacy. statistical significance of observed differences were evaluated by the log-rank test. wilcoxon signed-rank test was used to compare abpi before and after revascularization. results patients were followed at the swiss cardiovascular centre at three and six months and then annually by clinical examination, abpi measurement, and duplex scan to en- sure the patency of the profunda femoris artery. there was no -day mortality in the group of claudicants, but two patients ( %) with extreme critical ischemia died postoperatively from myocardial infarction. perioperative complications are seen in table . minor surgical com- plications occurred in five ( %) cases: one ( %) superficial infection and three ( %) postoperative hematomas were surgically evacuated under local anesthesia. one ( %) developed postoperative pneumonia. mean postoperative abpi was . . in ( %) patients; it improved signifi- cantly (> . ) after profundaplasty. the difference in pre- versus postoperative abpi was less than . . sustained clinical treatment efficacy according to rutherford [ ] was % at three years (fig. ). in five ( %) legs, a femoropopliteal reconstruction was performed during follow-up ( in claudicants, for critical limb ischemia). in five ( %) legs, an occlusion of sfa was postoperatively treated by pta at an average of five months after the initial procedure. two ( %) iliac arteries were stented to improve inflow. tlrs included two ( %) ptas of the distal profunda. the overall tlr rate was ( %), with some arteries undergoing more than one pta. cumulative freedom from surgical reintervention was % at three years. there was a difference between clau- table patient characteristics age (mean, yr) ± female ( %) male ( %) fontaine ii ( %) fontaine iii ( %) fontaine iv ( %) smoking ( %) diabetes mellitus ( %) renal insufficiency ( %) obesity ( %) dyslipidemia ( %) hypertension ( %) copd ( %) copd = chronic obstructive pulmonary disease, renal insuffi- ciency = creatinine > mg/ml, dyslipidemia = under treatment with statins, obesity = body mass index > kg/m table perioperative morbidity hematoma ( %) wound infection ( %) myocardial infarction ( %) pneumonia ( %) world j surg ( ) : – dicants ( , %) and patients with cli ( , %). clinically, subgroup analysis showed an upward shift in the ruther- ford classification in claudicants versus cli. healing of ischemic lesions was not seen in any of the nine ( %) legs. in the remaining ones, two ( %) major and two ( %) minor amputations were performed. discussion profundaplasty alone is not commonly performed anymore. it has been replaced by vascular reconstructions and cath- eter-based interventions. the inevitable question today is: does surgical profundaplasty have any role in the modern management of peripheral vascular disease? the surgical importance of the profunda femoris artery was discussed by morris et al. [ ] and leeds et al. [ ] in the early s. the revascularization of the deep femoral artery to treat peripheral arterial occlusive disease was introduced by natali in [ ]. cotton and roberts [ ] popularized the deep extended profundaplasty in the s. martin and bouhoutsos [ ] favored a patch over a short length. the first series was published by martin and bouhoutsos [ ], but it dealt mainly with proximal inflow procedures. jamieson [ ] declared that profundaplasty should be used to treat only critical ischemia and was not indicated when the superficial femoral artery is patent. in our unit, we knowingly apply it to patients with claudica- tion, thinking of it rather as part of general management than as a last resort prior to amputation. in our unit, pro- fundaplasty is performed in patients with a patent superfi- cial femoral artery ( %) and in patients with an occluded superficial femoral artery ( %). it has been compared to femoropopliteal reconstructions as well [ ]. to clarify the effect of profundaplasty alone, we excluded patients with a patent sfa from the analysis. many opponents of profundaplasty think it has a very limited hemodynamic effect [ – ]. however, in our study there was a significant postoperative increase in abi (mean = . – . ). of the patients, % had an improvement of greater than . compared with their preoperative values. clinical improvement after profundaplasty has been reported [ – ], but generally the results have been controversial: rollins et al. [ ] reported healing of ulcers in % in a small series. cotton and roberts [ ] reported success in %, treating patients with severe claudica- tion, rest pain, and ulcers. fugger et al. [ ] reported improvement in % in fontaine stage iii ischemia and % in iv. amputations could not be avoided. our group has compared the results of surgical profundaplasty to those of pta [ ]. in our study profunda revascularization was not sufficient in fontaine class iv ischemia (healing in none of the of cases), but it was beneficial in patients with rest pain. in our series, nine ( %) ptas were performed within one year of the operation. interestingly, five ( %) of our patients had a pta of their sfa, probably due to the introduction of modern advanced guidewires that started appearing during the study period. in this situation the patch may well facilitate access for the intervention. in our series, bovine pericardial patch was used in all cases, leaving the vein intact for further options. one ( %) superficial infection was seen. miksic and novak [ ] re- ported impaired results in connection with pta/stenting of the iliac artery. in our series, pta/stenting of the iliac artery was performed in % to improve inflow. in our series, profundaplasty showed a cumulative rate of freedom from any surgical revascularization in % at three years, which can be compared to the results of sutter et al. [ ], who showed a % rate at five years in patients with fontaine stage ii. sustained clinical treatment efficacy was % at three years, which compares favorably with the results of jamil et al. [ ], who found a % success rate in a mixed series of patients. patients with critical ischemia may benefit from pro- fundaplasty as well. however, in the nine patients with cli and tissue loss, none of the ulcers healed. conceivably, all amputations were performed in this group. similar results have been reported by miksic and novak [ ]. cli with time in months . . . . . . survival censored fig. kaplan–meier analysis for sustained clinical efficacy accord- ing to rutherford et al. [ ] world j surg ( ) : – tissue loss can be seen as an indication for femoropoliteal reconstruction, as reported by martin and bouhoutsos [ ]. remote superficial artery endarterectomy and distal stenting have been reported by rosenthal et al. [ ] with a primary patency rate of % at months. the procedure includes femoral endarterectomy if needed. we have no experience with the technique described by moll et al. [ ], but obviously it is technically more demanding than pro- fundaplasty alone. in our study, a short hospital stay and a low rate of complications (no mortality or major morbidity in patients with claudication) were seen. amputations and mortality were restricted to patients with catastrophic critical ische- mia without any possibility of surgical revascularization. as such, profundaplasty does not mean difficulties in case vascular reconstruction is later needed, and the vein is left intact. the bovine pericardial patch is easy to access sur- gically, and it can readily be punctured for endovascular interventions. limitations of our study include its retrospective nature and its relatively small number of patients. however, our follow-up coverage was good and the results present proof of concept for the procedure. in conclusion, profundaplasty, either alone or combined with proximal or distal endovascular intervention, can be used in selected patients suffering from claudication or critical ischemia. it brings good relief of symptoms and objectively improves distal circulation. the operation is straightforward and can be performed with short hospital- ization and low complication rates. profundaplasty is use- ful in critical ischemia with rest pain, but it should not be performed in patients with ischemic tissue loss. references . earnshaw j ( ) surgical options for treatment of profunda stenosis. in: greenhalgh rm (ed) towards vascular and endo- vascular consensus. london, biba, pp – . martin p, renwick s, stephenson c ( ) on the surgery of the profunda femoris artery. br j surg : – . rutherford r, baker j, ernst c, et al. ( ) recommended standards for reports dealing with lower extremity ischemia: re- vised version. j vasc surg : – . morris gc, edwards w, cooley d, et al. ( ) surgical importance of the profunda femoris artery. arch surg : – . leeds rh, gilfillan rs ( ) revascularisation of the ischemic limb. arch surg : – . natali j ( ) by-pass using the deep femoral artery (technique and indications) j chir (paris) : – . cotton lt, roberts vc ( ) extended deep femoral angio- plasty an alternative to femoropopliteal bypass. br j surg : – . martin p, bouhoutsos j ( ) the medium term results after profundaplasty. br j surg : – . jamieson c ( ) reconstruction of, and to, the profunda femoris artery. in: greenhalgh rm (ed) vascular surgical techniques: an atlas. london, wb saunders, pp – . meyer e, adar r ( ) comparison of extended deep femoral angioplasty and femoropopliteal bypass graft in severe ischemia of the leg. world j surg : – . fugger r, krethschmer g, schemper m, et al. ( ) the place of profundaplasty in surgical treatmen of superficial femoral ar- tery occlusion. eur j vasc surg : – . jamil z, hobson rw, lynch tg, et al. ( ) revascularization of the profunda femoris artery for limb salvage. am surg : – . van der plas jp, van dijk j, tordoir jh, et al. ( ) isolated profundaplasty in critical limb ischemia – still of any use? eur j vasc surg : – . kalman pg, johnston kw, walker pm ( ) the current role of isolated profundaplasty. cardiovasc surg : – . sutter t, jauch kw, erlewein g, et al. ( ) long-term results of profundaplasties. vasa : – . mccoy dm, sawchuk ap, shuler jj, et al. ( ) the role of isolated profundaplasty for the treatment of rest pain. arch surg : – . rollins dl, towne jb, bernhard vm, et al. ( ) isolated profundaplasty for limb salvage. j vasc surg : – . diehm n, savolainen h, mahler f, et al. ( ) does deep femoral artery revascularization as an isolated procedure play a role in chronic critical limb ischemia? j endovasc ther : – . miksic k, novak b ( ) profunda femoris revascularization in limb salvage. j cardiovasc surg : – . rosenthal d, martin jd, smeets l, et al. ( ) remote super- ficial femoral artery endarterectomy and distal aspire stenting: results of a multinational study at three-year follow-up. j car- diovasc surg (torino) : – . moll f, ho g, joosten p et al ( ) endovascular remote endarterectomy in femoropopliteal long segmental occlusive disease. a new surgical technique illustrated and preliminary results using a ring strip cutter device. j cardiovasc surg (torino) ( suppl ): – world j surg ( ) : – small is beautiful: why profundaplasty should not be forgotten abstract methods statistical analysis results discussion references << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (none) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false 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] /vsamples [ ] >> /colorimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg coloracsimagedict << /tilewidth /tileheight /quality >> /jpeg colorimagedict << /tilewidth /tileheight /quality >> /antialiasgrayimages false /downsamplegrayimages true /grayimagedownsampletype /bicubic /grayimageresolution /grayimagedepth - /grayimagedownsamplethreshold . /encodegrayimages true /grayimagefilter /dctencode /autofiltergrayimages true /grayimageautofilterstrategy /jpeg /grayacsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /grayimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg grayacsimagedict << /tilewidth /tileheight /quality >> /jpeg grayimagedict << /tilewidth /tileheight /quality >> /antialiasmonoimages false /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputcondition () /pdfxregistryname (http://www.color.org?) /pdfxtrapped /false /description << /deu /enu >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice acta .indb udmurt auto- and hetero-stereotypes about physical beauty acta ethnographica hungarica ( ), – ( ) doi: . / . . . . – /$ © akadémiai kiadó, budapest galina a. niki na udmurt ins tute of history, language and literature, ural branch of russian academy of sciences (udmurtskiy ins tut istorii, yazyka i literatury uro ran), izhevsk, russia abstract: for udmurtians, physical beauty is an attractive and impressive physique. in the late th century, udmurt criteria for evaluating physical beauty were infl uenced by the aesthetic ideals of neighbouring peoples. a beautiful girl was supposed to have slavic or turkic features but not udmurt ones. northern udmurts believed that an attractive young woman was fair- complexioned with fair hair and blue eyes, while southern udmurts admired women with dark hair and black eyes. one can still hear them saying, “she is so beautiful, she doesn’t look like an udmurt girl at all,” which is followed by more precise information, such as, “she looks like a russian/tatar woman.” this stereotype still exists among the udmurts and their neighbouring peoples, especially the russians. keywords: udmurts‒russia, personal beauty, beauty culture, body image, social aspects of human body physical beauty is known to refer to attractive appearance and impressive physique. in this respect udmurt folk songs are of special interest to researchers as they provide useful information on ideals of beauty. on careful analysis of southern and northern udmurt lyrical songs, one can notice that auto-stereotypes about physical beauty in those songs have subtle nuances. according to northern udmurts, a beauty is a woman with a golden plait, blue eyes and a faint blush. her appearance corresponds with her light-coloured clothes. in the opinion of southern udmurts, a beauty is a woman with dark hair and eyebrows, her eyes as dark as black currants. her clothing is compared to a full-blown fl ower of italmas (european globe fl ower) and her voice to a nightingale singing. i believe the difference in beauty perception by the northern and sourthern udmurts is infl uenced to some extent by aesthetic ideals of their neighboring peoples. a beauty was considered to have slavic (in the northern areas, close to kirov oblast with russian population) or turkic features (in the southern areas with turkic population), but she was not supposed to look like an udmurt woman. even nowadays the udmurts, especially elderly women, can say: “uchky-ay, kyč̈e cheber, udmurt tusyz no övöl” (look! what a beauty, she does not have the appearance of an udmurt), and can add: “she looks like a acta .indb acta .indb . . . : : . . . : : galina a. niki na russian woman” or “she looks like a tatar woman.” so far this stereotype has been popular both among the udmurts and their neighbouring peoples, especially among russians. in the th century the northern udmurts compared attractive women to dolls made of clay (syuymuno) and wax (syus’muno), or to russian dolls (z̈uchmuno): milyam gine suzermy suzer no-a ma? lavkaye no puktylem z̈uchmuno kad’ [our sister, what a beauty! she looks like a russian doll from a shop] (b – v : ). i am not inclined to consider the phrase “a russian doll” to be infl uenced by russian beauty stereotypes. the udmurts must have meant children’s painted toys, which differed signifi cantly from udmurt handmade rag dolls. in some cases a dymkovo toy (a painted clay doll) was implied, especially if it was compared to a clay doll “syuymuno”. the folk ideals of beauty are found not only in folklore texts but also in ethnographic data. thus, for instance, nikolay pervukhin, the inspector of national schools in glazov county of vyatka province, described an udmurt beauty as follows: “to be considered a beauty, a woman must be primarily of medium height, plump, and she must have big plump arms and legs as an evidence of her ability to work well… dark, rather oblong than round eyes, a straight nose of medium size, dark narrow long eyebrows. the votyaks believe these are the features a votyak beauty has” (p : – ). such beauties were seldom found, so the author adds: “the above mentioned features are of some importance to young boys, but their parents pay less attention to these characteristics, they are more concerned with a bride’s health and housewifeliness.” as for a bridegroom, his attractiveness was not important even to the bride’s parents. a woman never refused to marry a man just because he was not good looking enough (p : ). psychiatrist and neurologist vladimir bekhterev gave the following description of udmurt females: “they mostly have red hair, a broad face, blue eyes, a large mouth and nose with a low nasal bridge, plump chest and belly” (b : ). according to irina nazmutdinova’s research, the ancestors of the udmurts living now in kuyedinsky district of perm krai characterized a beauty as being “clean” (chylkyt). it suggests that the udmurts emphasized not only her neatness and cleanliness, but also her attractiveness (n b: ). moreover, according to my colleague lyudmila karpova’s mother, who is from the uva district of the udmurt republic, the above-mentioned word was also used to underline a woman’s physical beauty. the state archive of the kirov oblast contains a manuscript with a very remarkable description of the udmurt beauty ideal: “to be considered beautiful, a woman should be of medium height and plump enough, she should have big plump arms and thick (as a sign of labor force) legs. her face should be round, white and rosy, without pockmarks. a thick plait is supposed to be attractive, light chestnut hair is preferable. the bright red hair is considered to be the ugliest women’s hair. a small mouth acta .indb acta .indb . . . : : . . . : : udmurt auto- and hetero-stereotypes about physical beauty and lips of medium size, dark eyes which are rather more oblong than round, a straight nose of medium size, dark narrow and long eyebrows... ” however, folklore texts do not contain a detailed description of physical attractiveness of young men. apparently, it was primarily associated with their physical performance, endurance, strength, agility, and proportional physique. a man is considered handsome if he is as lean as a wax candle, pine or maple (yus’ nyl kad’, puzhym/badyar kad’ voskres), and as strong as a lynx (balyan kad’). he is supposed to have a smooth face without any pockmarks, fair or dark curly hair, but by no means bright red hair. a young man “should be lean, agile and well-built. his arms and legs should be large. he has blue eyes, a medium-sized nose, mouth, and lips. less attention is paid to his facial cleanliness.” “the red hair index” is certainly high among the udmurts: the number of redheads varies from to % in different groups (d : ). the readheads’ psychology is distinctive: they are more sensitive, vulnerable, and they have a specifi c worldview (k –v : ). researchers also noted the endurance of the udmurts, “although they are slim” (d : ). as a rule they are of medium build, but not overweight, and they have a slender, muscular body (k –v : ). although the udmurts’ attitude towards russians was cautious, often mistrustful and suspicious, the udmurts tended to overestimate their neighbours. one of the pre-revolutionary researchers made a remark about it: “they do not appreciate their nationality at all, the highest praise for the votyaks is to say that they resemble russians.” unfortunately, this stereotype is still alive and well among some udmurts, including the urban population: the udmurts keep making derogatory remarks about themselves. noting this phenomenon, one should remember that the historical interaction between the udmurts and russians was asymmetrical: russians were more active than the udmurts. besides, one should not forget about the purposeful and aggressive missionary activity of the orthodox church. however, it cannot be suggested that udmurt society has always accepted any form of russian borrowings positively. thus, for instance, one of the udmurt songs provides a fi guratively negative attitude towards them: chil’pam chalma, ž̈utkam chalma yyrad sekyt yötïz-a? yyrad sekyt öy yötysal, z̈uch kyshno luemed potïz-a? woven, embroidered chalma [an udmurt female headdress], did you fi nd it heavy? it would not be heavy, maybe you want to become a russian’s wife? (p : ) physical beauty was rarely considered to be a self-value. firstly, it was always associated with a person’s spirituality, morality, diligence, physical health, and as for women – with the state archive of the kirov oblast. fund . inventory . file . sheet – verso. the state archive of the kirov oblast. fund . inventory . file . sheet – verso. the state archive of the kirov oblast. fund . inventory . file . sheet - verso. acta .indb acta .indb . . . : : . . . : : galina a. niki na their reproductive functions as well. the following sayings prove it, “en uchky cheberez shory, uchky solen uzhamez shory” (do not pay attention to the person’s beauty, pay attention to their work), “pushkaz övöl ke, vylaz ud lyaky” (if there is nothing inside, you cannot add to it). in addition, an attractive physique has always been related to intelligence, “cheberen köt ug tyr” (you can not be full with beauty), “cherez č̈ok, viz’my medlo” (a person’s beauty is not as important as their intelligence) (p ). in his letters, uno holmberg also highlighted that the udmurts assigned paramount importance to a person’s health, but not to their beauty: “now pagan votyaks are buying their brides. the price for a bride does not depend on her beauty, her eyes and hair, but on her health. ‘it is worth paying for her, because she is strong and hardworking,’ say the votyaks. but a thin girl does not cost much. men choose their wives according to their ability to work. kalym, the price for a bride, of course, varies depending on the economic well-being of the area. i guess a bride in ufa province is twice more expensive than in kazan province” (l et al. : ). the researcher also considered the age when people can get married: “sometimes the votyaks can make a deal rather early when their children are too young. once i stayed at one votyak’s in the birsk district, he was years old, but his son was already years old. when i started to ask him how old he was when he got married, i was surprised to learn that he had married at the age of . his brother, who also lived in the same house, married at the age of . but their wives were both signifi cantly older than their husbands” (l et al. : ). in fact, udmurt wives were older than their husbands. the situation was especially typical of families with a small number of females. in relations with the outside world, the udmurts are often helpless, defenseless, and closed to something new and extraneous. according to socrates, the body does not get ill apart from the soul. psychological mood plays a vital role in the prevention and treatment of diseases, and in this situation the role of the environment, especially the family, cannot be overestimated. according to current data, married udmurts feel more comfortable and happier as they are supported by their families. not coincidentally, single people who have never been married commit suicide more often than the married ones: the index is . % among the udmurts, and . % among russians (v : ). in the past, udmurts had large families consisting of several generations. family communications infl uenced the feelings of dependence and psychological attachment to relatives. therefore, any confl ict could inevitably destroy the current relationships and infl uence deep personal feelings which resulted in the high sensitivity of the udmurts. according to recent research, social exclusion plays a potentially negative role in maintaining health and can eventually cause illness (m ). this data also emphasizes the vital importance of the following behavioural dominant: a human being should live in harmony with other people: “peace with oneself due to the peace with others” (k – v : ). the opinion of others is of crucial importance for the udmurts – it can literally destroy their fragile emotional health. the community was aware of the danger of alcohol intake and tried to restrict its consumption by young people. the rules of morality, decencies and visitor etiquette acta .indb acta .indb . . . : : . . . : : udmurt auto- and hetero-stereotypes about physical beauty related to the use of intoxicating drinks are found in folkloric texts: “kudz̈em murt viz’temles’ no urod” (a drunken person is worse than a fool), “kurytse yuysa, z̈eche ud poty” (drinking alcohol you will not become good), and so on. a drunken person was called disapprovingly tordos (wino) (n : ). according to fi eld material by irina nazmutdinova, udmurts do not like men who are vulgar and garrulous, but their ability to carry out different kinds of work is highly appreciated. udmurts expressed their disapproval if there was a discrepancy between male behavior and ideas of masculinity. those men were contemptuously called zyzykyshno (literally: a thin woman). to make derogatory remarks about such kind of men, zakamsk udmurts could use a harsh word apakay (comes from the word apay – sister), an unpleasant phrase alama nylkyshno (worthless woman), or an insulting russian word baba (woman) (n a: ). as for hetero-stereotypes about the physical beauty of the udmurts, it seems that the majority of pre-revolutionary researchers and observers did not consider the udmurts to be a beautiful ethnic group. while describing their physical appearance, the researchers chose such words as “weak,” “puny,” “frail” and “feeble,” and also emphasized their small, deep-set eyes, prominent cheeks, average height, and red hair (k : – ). for example, alexander radischev, while traveling through the territory of udmurtia in the autumn of to a -year exile, briefl y summarized about the udmurts: “the votyaks are almost like russians, most of them are married to russian women. their houses are already heated by wood-burning stoves. there are many mountains beginning from the town of zura, although they are small, but steep. the votyak women are not beautiful. the votyaks sing while riding a horse like russian coachmen. they tend to be cheerful rather than sad…” (r : ). according to current observations on the youth, including young rural udmurts studying at udmurt state university, they do not tend to belittle their attractiveness and physical appearance, giving preference to the turkic or slavic type of beauty. however, it is not as inherent in rural young people as it is in young urban udmurts. the traditional stereotype of “the udmurt beauty” is being reassessed by the urban young people. empirical experience shows that the preferences of young udmurts are infl uenced by the current fashion, western standards and criteria for beauty, which dominate in the modeling business. besides, we should remember that folk culture has formed its own knowledge about the means of hygiene and cosmetology, which help to maintain physical beauty and health and to hide some physical appearance defects. nowadays udmurts are actively involved in assimilation processes. it is believed that more beautiful children are born in ethnically mixed families as a result of “blood mixture,” and it seems to be true when it comes to the udmurts. we must also remember that parents cherish their children, care about their diet, do not force them to work too hard, care about their health, education, and so on. all this excludes the harm to children’s physical and mental health, which contributes to their good-looking appearance. acta .indb acta .indb . . . : : . . . : : galina a. niki na references cited b , e. b. – v t. g. pesni yuzhnykh udmurtov [songs of the southern udmurts]. izhevsk: udmurt. in-t istorii, yaz. i lit. (udmurtskiy fol’klor). b , vladimir mikhaylovich votyaki i ikh istoriya i sovremennoye sostoyaniye [votyaks, their history and current status.] i-ii. vestnik yevropy [ ]( ): – ; [ ]( ): – . d , a. i. antropologicheskaya kharakteristika severnykh i tsentral’nykh udmurtov [anthropological characteristics of northern and central udmurts]. (novyye issledovaniya po etnogenezu udmurtov [new research on udmurt ethnogenesis: proceedings]). izhevsk: udmurt. in-t istorii, yaz. i lit. k , v. byt votyakov sarapul’skogo uyezda vyatskoy gubernii [everyday life of the votyaks in sarapulsky county, vyatka province]. kazan’: tip. imp. un-ta. k a. s. − v v. e. ob etnose, lichnosti, tolerantnosti [ethnicity, identity and tolerance]. vestnik udmurtskogo universiteta. : − . l , seppo – m , tatiana. g. – s , ranus. puteshestviya k udmurtam i mariytsam. pis’ma uno khol’mberga. – matkat udmurttien ja marien luo. uno holmbergin kirjeitä vuosilta ja [trips to the udmurts and maris. uno holmberg’s letters for the years of and ]. st. petersburg: evropeiskii dom. m , david psikhologiya i kul’tura [psychology and culture]. st. petersburg: praym- yevroznak. n , irina konstantinovna a semeynyy etiket v sisteme traditsionnoy i sovremennoy kul’tury udmurtov [family etiquette in the system of udmurt traditional and modern culture]. dissertation manuscript. izhevsk: chuvash. gos. un-t im. i.n. ul’yanova. rgb od, – / b zhenshchina v traditsionnom udmurtskom obshchestve: ideal krasoty i obraz khozyayki [woman in traditional udmurt society: the ideal of beauty and the image of housewives]. iii informatsionnaya shkola molodogo uchenogo sbornik nauchnykh trudov. − . ekaterinburg: tipografi ya „ural’skiy tsentr akademicheskogo obsluzhivaniya”. n , galina arkad’yevna narodnaya pedagogika udmurtov [folk pedagogy of udmurts]. izhevsk: udmurtiya. p , t. g. (ed) udmurtskiy fol’klor: poslovitsy, aforizmy i pogovorki [udmurt folklore: proverbs, aphorisms and sayings]. izhevsk (ustinov): udmurtiya. acta .indb acta .indb . . . : : . . . : : udmurt auto- and hetero-stereotypes about physical beauty p , n.g. (ed) eskizy predaniy i byta inorodtsev glazovskogo uyezda . sledy yazycheskoy drevnosti v suyevernykh obryadakh obydennoy zhizni votyakov ot kolybeli do mogily [sketches on traditions and way of life of foreigners in the glazov county . traces of pagan antiquity in superstitious rituals of everyday life of votyaks from cradle to grave]. vyatka: gub. tip. p , m.i. udmurt kalyk kyrz̈an”yos [udmurt folk songs]. izhevsk: udgiz. r , alexander nikolaevich polnoye sobraniye sochineniy [complete set of works]. vol. . (ed by borozhdin a. k. – lapshin i. i. – schegolyev p. e.) sankt petersburg: izdaniye m. i. akinfi yeva. (biblioteka russkikh klassikov № – ). v v. v. etnokul’tural’nyye osobennosti suitsidal’nogo povedeniya psikhicheski bol’nykh v udmurtii [ethnocultural features of suicidal behavior of psychiatric patients in udmurtia]. dissertation manuscript. moskva: gosudarstvennyy nauchnyy tsentr sotsial’noy i sudebnoy psikhiatrii. niki na, galina arkad’yevna is an ethnographer, doctor of historical sciences ( ), professor ( ), and state honored scholar of the udmurt republic ( ), currently at the udmurt ins tute of history, language and literature, ural division of the russian academy of sciences in izhevsk, russia, where she has worked since as a senior researcher in the department of ethnology and sociology; from to she was deputy director for research, and since she is the lead researcher in the department of historical research. academic interests and fi elds of research: issues of social organiza on of the udmurt peasants, folk knowledge (pedagogy, medicine, metrology). since she has been engaged in research of the udmurt diaspora on ethno-cultural and modern ethno- poli cal processes. email-address: niki na@udnii.ru acta .indb acta .indb . . . : : . . . : : << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (dot gain %) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /tags /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /cmyk /dothumbnails false /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - /imagememory /lockdistillerparams false /maxsubsetpct /optimize false /opm /parsedsccomments true /parsedsccommentsfordocinfo true 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acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /createjdffile false /description << /ara /bgr /chs /cht /cze /dan /deu /esp /eti /fra /gre /heb /hrv (za stvaranje adobe pdf dokumenata najpogodnijih za visokokvalitetni ispis prije tiskanja koristite ove postavke. stvoreni pdf dokumenti mogu se otvoriti acrobat i adobe reader . i kasnijim verzijama.) /ita /jpn /kor /lth /lvi /nld (gebruik deze instellingen om adobe pdf-documenten te maken die zijn geoptimaliseerd voor prepress-afdrukken van hoge kwaliteit. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /pol /ptb /rum /rus /sky /slv /suo /sve /tur /ukr /enu (use these settings to create adobe pdf documents best 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need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ the objectivity of truth, morality, and beauty the objectivity of truth, morality, and beauty steven james bartlett abstract whether truth, morality, and beauty have an objective basis has been a perennial question for philosophy, ethics, and aesthetics, while for a great many relativists and skeptics it poses a problem without a solution. in this essay, the author proposes an innovative approach that shows how cognitive intelligence, moral intelligence, and aesthetic intelligence provide the basis needed for objective judgments about truth, morality, and beauty. . . . the author has chosen to issue this essay as a free open access publication under the terms of the creative commons attribution-noncommercial-noderivs license, which allows anyone to distribute this work without changes to its content, provided that both the author and the original url from which this work was obtained are mentioned, that the contents of this work are not used for commercial purposes or profit, and that this work will not be used without the author’s or his executor’s permission in derivative works (i.e., you may not alter, transform, or build upon this work without such permission). the full legal statement of this license may be found at http://creativecommons.org/licenses/by-nc-nd/ . /legalcode © steven james bartlett < > the objectivity of truth, morality, and beauty steven james bartlett his famous trio—truth, morality (or the good), and beauty—was firmly set at the very center of western philosophical thought ever since plato wrote about them, and there it has remained, subject to the vagaries of changing philosophical fashion and style, vested interests, and preferred paradigms. for more than two millennia, the same fundamental question has haunted the members of the trio, is objectivity in connection with any one or more of them possible, and if so, can such objectivity be established so as to satisfy the standards of rational thought? as the formal science of mathematics has developed, and somewhat less so as physical science has reached periods of great confidence in its results, only to be revised and recast as a consequence of conceptual revolutions, objective truth has seemed more readily approachable than has objectivity in connection with beauty or morality. and yet, not even as the most secure and demonstrable of all areas of human knowledge, mathematics, too, has been forced to take steps backwards or sideways, as it has been compelled by its own findings to recognize forms of intellectually humbling internal theoretical limitation. some of these limitative proofs were developed by gödel, whose work has become best known, but results by a succession of other mathematicians—including kleene, rosser, kalmár, gentzen, church, turing, post, tarski, mostowski, löwenheim, skolem, henkin, wang, and others—have extended, amplified, modified, and in a variety of ways and, to a degree, have even found ways to circumvent some internal limitations of t < > mathematics. their contributions, developed from differing formalized perspectives, point in the direction of what i have termed “framework-relativity,” which recognizes that all claims to knowledge, mathematical or otherwise—including the claim i am making here—are intimately tied to, and limited by, the conceptual frameworks that make those claims possible. the same pattern of development has been witnessed in physics, where special and general relativity recognize the inseparable connection of physical results from the reference frames in terms of which physical laws are expressible and are subject to confirmation or disconfirmation. quantum theory, in a similar way, is based on the parallel recognition of essential and unbreakable ties among the physically observable, the physical observer, and the theoretical framework presupposed in order to interrelate the preceding two. these theoretically intimate, essential, nonseverable relationships of connection between the objects measured by physics and the theoretical frameworks that are presupposed by agent-bound, measurement-bound descriptions of physical regularities that we can come to recognize, all tell very much the same theoretical story as in mathematics: that whatever we can know, whatever we are capable of formulating and communicating, whatever we are able to prove, all of these rely for their very possibility and meaning upon the frames of reference that we cannot help but presuppose in the process. framework-relativity is, however, not “relativism,” a now-widespread popular presumption that claims—no matter what purported “truths” are discovered or believed to be proved—that such “truths” are no more than provisional, tentative, and dismissible whenever we feel like shrugging them off, since all we need to do is remind ourselves that “everything really is subjective,” that “nothing can be known objectively to be true,” etc. there are, of course, good, strong, and rationally convincing arguments against relativism, the best of which, in my view, points to the fact that the relativist’s own position cannot possibly be articulated without < > presuming the very objectivity that he or she wishes to deny. but here i am not concerned to refute relativism, only to dismiss it as irrelevant to the concept of framework-relativity, which, contrary to relativism, recognizes the objectivity of results relative to the frameworks those results presuppose. this is not a sophism, not a smokescreen to disguise, elevate, and dignify the “merely relative” by coining an unfamiliar phrase. let me give some examples of objective results that are framework-relative: euclidean geometry’s theorems are objective in this sense; they are provably true relative to a set of definitions, postulates, and rules of inference. similarly, riemannian geometry, which rejects euclid’s parallel postulate, leads to a set of true propositions, which are provable relative, again, to a specified set of definitions, postulates, and rules of inference. lobashevskian geometry, which also repudiates the parallel postulate in a different way, leads to demonstrable results relative to an alternative set of definitions, postulates, and rules of inference. all such results are objectively demonstrable. what meaning does the term ‘objectivity’ have, other than simply the capacity to establish results that are not subject to controversy and can be replicated by competent colleagues in a given discipline—provided that they accept the framework which the establishment of such results must presuppose? if they don’t accept that framework, they beg the question, they engage in what philosophers call a petitio principii—they refuse to abide by the rules of the game at issue, perhaps because they wish to use alternative rules and play a different game, or perhaps because they are being intellectually recalcitrant, believing that the skepticism they express is not itself self-undermining (which it is). as long as you accept the rules of chess, some moves are objectively good, and others are objectively bad. as long as you accept the definitions, postulates, and rules of as we shall see later on, such “competence” means having in common with colleagues a relevant form of intelligence without which the results in question could not be obtained or adequately understood. see note . < > inference of euclidean geometry, then there are results in euclidean geometry that are objectively provable. this is what ‘framework-relativity’ means, and the metatheory that leads to the recognition of framework-relativity is itself objectively provable—by showing that any (possible) attempt to deny it leads to self-referential inconsistency of a particularly devastating kind. mathematicians have long been both aware and appreciative of the essential interrelationship between the formal systems they study and the validity of the results those formal systems entail. physicists have, during the century since einstein’s special and general theories of relativity, come to understand and also appreciate how the conceptual structures in terms of which their observations are both made and then are formulated reveal an underlying logic of framework-relativity. neither mathematicians nor physicists have, as a result of this growing framework-relative awareness, given up the search for, and claims on behalf of, objectively demonstrable results. this is not because mathematicians and physicists are intellectually stubborn or obtuse, it is because ‘objectivity’ simply means—and the very possible meaning of the term itself necessarily requires—framework-relativity. let us suppose, for the sake of moving on, that there is a well-defined sense in which mathematics and physics can attain to objectively valid results, objective truths. in admitting this, it is not necessary that we always know for certain that these results are, at the time, objectively valid, but only that, given sufficient time and continuing effort, objective truth stands as a meaningful goal in mathematics and in physics, a goal that satisfies basic tenets of rationality. (what i generally mean by the last phrase will be made clearer in the context of our later discussion of forms of intelligence). let us turn to morality and beauty, those more nebulous and less intellectually manageable ideas compared with truth. is there any possible sense in which sample publications by the author that bear this out will be found under “references” at the end of this paper. < > propositions of morality or in which those of aesthetics can be “objectively established?” these two areas, morality (or ethics) and aesthetics (or the theory of beauty), have remained the ultimate refuges of unbridled subjectivity. for these are areas in which—by nearly universal admission by those who are not afflicted by unyielding religious dogma—it is believed that “one person’s meat is another’s poison,” that “my belief is as good as yours,” that “thinking makes it so,” and so on. in the world of reality, aesthetics therefore has been associated with “personal taste,” and morality with “personal moral inclination.” tastes and inclinations are inherently subjective terms and suffer from the aura of vagueness and the arbitrariness of relativism. to go beyond the merely subjective in connection with beauty and morality, we will take a path not previously travelled which involves an understanding of two unfamiliar and newly identified varieties of human intelligence. major forms of human intelligence cognitive intelligence is human iq an objectively determinable thing? are cognitive abilities such as verbal comprehension, problem-solving, pattern recognition, memory, mental processing speed, etc., measurable, and if so, are the conclusions reached on the basis of such measurements in any sense “objective”? the answer to this question is as non-arbitrary as are the results derived in a system of euclidean geometry. once definitions of the relevant cognitive skills are specified, tests are constructed to measure those skills, the tests are then given to sample groups of people, and finally the test results themselves are carefully evaluated to answer the question, do individuals whose test scores are high (or low) reliably exhibit the designated skills to a high (or low) degree? additional, alternative/supplementary ways to assess the skills being tested may then be brought in to confirm the test results. once a psychometric test has been validated in these < > ways with large populations, to ask whether the test results are “objective” is to ask one of three questions: whether the definitions of the relevant skills are to be accepted, or whether the test that has been constructed actually succeeds in measuring those skills effectively, or sometimes a third and misconceived question is asked, to which we’ll come in a moment. the second question is of course more easily answered: we look for additional means to strengthen the iq test validation process. there are numerous ways to do this: personal interviews with the test subjects, data about their cognitive success rates in real life, etc. it is the first question that often misleads people, especially those who believe that definitions are somehow dictated by reality, and, because they believe this, they disagree about what “real intelligence” actually is. reality, whether we may be concerned to designate specific cognitive skills, or whether we may want, for example, to specify the features that define and differentiate biological species, does not come pre-classified or pre- compartmentalized. it is rather our own interests and goals that lead us to regard certain cognitive skills, or certain biological characteristics in the case of species, to be significant, important, or relevant, and we then formulate definitions that reflect those interests and goals. we value such cognitive skills as verbal abilities, spatial relations skills, the ability to calculate, the ability to remember, the ability to comprehend, to imagine, to think critically. these cognitive skills reflect basic human interests and goals, and those interests and goals motivate us to designate these and related skills as important. iq tests are simply constructed to test for the skills that we choose to define as cognitively important because they reflect our vested interests and goals. these interests and goals establish a framework relative to which we have developed ways on the kinds of definition and the belief in “real definitions,” see bartlett ( , chap. ). on the so-called species problem in biological taxonomy, see bartlett ( ). < > of testing individuals for the presence of those skills which our interests and goals lead us to recognize as “cognitive intelligence skills.” but there is a third question we need to mention, one that the iq skeptic insists upon asking about iq tests: whether people whose test results show them to have high (or low) iqs really are cognitively intelligent (or lacking such intelligence). to raise this question is again to engage in a petitio principii—to refuse to accept a set of rules that establishes a system that identifies certain skills as manifestations of “cognitive intelligence” as it has been defined by iq tests. either the skeptic is exercising his or her “right” to be intellectually uncooperative (wanting to play “chess” but refusing to accept the rules of chess), or underlying the question is a wish to assert the skeptic’s “right” to specify an alternative, broader, or narrower set of defined skills, and by so doing to formulate an alternative, broader, or narrower conception of “intelligence.” that latter “right” is always assured, and it has in fact been exercised by investigators of intelligence so as to produce conceptions of intelligence that are distinguishable from the standard skills associated with cognitive intelligence. the study of human intelligence at this time recognizes a variety of forms of intelligence, among them, emotional intelligence, social intelligence, as well as other varieties, and more recently in the author’s research, moral intelligence and epistemological intelligence. the multiplicity of kinds of human intelligence does not imply that any one of them is any the less amenable to objective measurement merely because other varieties have also been identified. the same situation exists, as we have seen, in connection with the family of alternative geometries. the existence of conceptual alternatives does in itself not stand in the way of objectivity. relative to each among the earliest authors, see, e.g., salovey & mayer ( ), gardner ( , / ), goleman ( ). the historical development of the concept of social intelligence can be found in going from one of these publications to the next: thorndike ( ), spearman ( ), bruner & tagiuri ( ), taft ( ), guilford ( ), eysenck ( ). bartlett ( ), bartlett ( , chap. ) and ( , chap. ). bartlett ( a). < > reference frame that clearly specifies what is to be identified and how, we are able to recognize and reach public agreement about whatever objects that frame of reference enables us to designate. this is most fundamentally what the term ‘objectivity’ means. moral intelligence we now shift our attention from cognitive intelligence to what i have elsewhere called “moral intelligence.” like the cognitive variety, moral intelligence is defined in terms of a set of skills. —once again it is important to be reminded, reality does not dictate the specific skills we select, but rather our goals and interests do; they determine what we value. the fact that values are basic and central to any concept of intelligence, of whatever variety, does not imply that we are therefore automatically dealing with “purely subjective,” “arbitrary,” or “vague” ideas. framework-relativity in connection with any given variety of intelligence means two things: (i) that a certain set of values is necessarily presupposed, values that underlie the interests and goals which the given form of intelligence manifests, and (ii) that it is relative to those values that the given variety of intelligence possesses the meaning we ascribe to it. if we make an effort to define clearly—in a manner that permits objective validation—the set of skills that we wish to recognize, then the resulting concept of intelligence that we formulate becomes capable of objective reference. the concept of moral intelligence can be defined in terms of a set of specific skills and dispositions (how an individual will likely behave). the skills and dispositions we select in defining moral intelligence is not arbitrary. in the case of cognitive intelligence, we look to human models—human exemplars—of high cognitive intelligence in order to direct attention to skills that we value in cognitively high-functioning individuals. in the case of moral intelligence, we do the same thing: see note , also bartlett ( a). < > we look to human individuals whom we judge to exemplify high-functioning moral reasoning and behavior. just as we have a traditional consensus that cognitively high-functioning individuals are to be found in connection with intellectually demanding high achievement, morally high-functioning individuals are found among outstanding spiritual leaders and great humanitarians; in addition, we also recognize high- functioning moral reasoning and behavior in those less celebrated, more ordinary people who dedicate themselves to human welfare: fighters against injustice, cruelty, bias, prejudice, and persecution, those who struggle and sacrifice to help the unfortunate, etc. there are many ways in which moral intelligence can be manifested. individuals whom we identify as morally high-functioning serve as a “reference group” in relation to which it is not a difficult matter to identify the dispositions and skills that characterize their way of thinking and of behaving. among the main dispositions and skills that i have identified in studying moral intelligence are these: a strong psychological aversion to participation in behavior that harms others, a fully functioning capacity for empathy, a well-developed sensibility that is expressed in normative weighing tied to aversion that a morally intelligent person feels when confronted by typical human aggression and destructiveness, and a strong moral conviction that bridges skills in moral reasoning with commitment to act accordingly. here in this short essay it is not my intent to describe in detail and to discuss the dispositions and skills related to moral intelligence, but rather to point to the fact that, once we have clearly formulated definitions of those dispositions and skills in hand, along with criteria that inform us how we can recognize those dispositions and skills in people, we then have at our disposal a frame of reference in terms of which for detailed discussions of the dispositions and skills that constitute moral intelligence, see notes and . < > it is possible to identify morally intelligent individuals. and once that reference frame is established, “moral intelligence” becomes objectively identifiable. once morally intelligent individuals are objectively identifiable, it is then a short step to identify “objective moral behavior,” which, it follows, is the behavior that morally intelligent people engage in. treatise-upon-treatise has been written about morality, attempting—by hook or by crook!—somehow to justify moral admonitions, and books-upon-books about ethics have urged reasons for the adoption of ethical principles. these works fill many of the shelves of libraries. moral and ethical discussions over millennia have been interminable, and they have led to no objectively establishable conclusions. they have led to dogmas and doctrines, to pronouncements, and to often bitter controversy. it is, however, possible to provide a clear and persuasive response to the question, does morality have objective validity? a clearly formulated concept of moral intelligence provides a natural and empirically-based means of understanding and conceptualizing moral reasoning and behavior, and it also provides us with a psychologically-based comprehension of why some individuals behave morally and others do not. aesthetic intelligence of the members of the illustrious trio, least amenable to objective validation has very likely been aesthetic judgment concerning beauty. what constitutes beauty and how is it to be recognized? are some works of art “objectively beautiful,” or is beauty merely in the eye of the beholder, an entirely subjective affair? is there any set of standards or criteria by means of which high aesthetic quality (and low) can be objectively recognized? bartlett ( and , chap. and passim.) < > again, the shelves of libraries are packed with treatises and disquisitions that attempt to answer these questions. i think it is fair to say that none has. an untried answer to the question follows readily from a recognition of a largely overlooked variety of human intelligence which it is appropriate to call “aesthetic intelligence.” as we shall see, once we gain an understanding of aesthetic intelligence, an acknowledgment of framework-relativity leads in a straightforward way to the objectivity of beauty, as it does in the cases of truth and morality. one of the most outspoken, articulate, and scientifically-oriented researchers in the field of aesthetics has been charles murray. his carefully compiled study, human accomplishment: the pursuit of excellence in the arts and sciences, b.c. to , takes a stand on behalf of the objectivity of scientific truth as well as the objectivity of beauty: judgment is separable from opinion in matters of artistic and scientific excellence. it is possible to distinguish the important from the trivial, the fine from the coarse, the credible from the meretricious, and the elegant from the vulgar. doing so is not a simple matter, and no single observer is infallible, but a realm of objective knowledge about excellence exists. that knowledge can be tapped systematically and arranged as data that meet scientific standards of reliability and validity. (murray, , p. xvi) murray was certainly aware of objections to his claim of aesthetic objectivity. among the main objections is the flat-out opposition to the very notion that aesthetic judgments can be objective. there is, he realized, “. . . hostility to the idea that discriminating judgments are appropriate in assessing art and literature, or that hierarchies of value exist—hostility as well to the idea that objective truth exists” (p. xviii). psychological hostility toward an idea is difficult and usually impossible to reason with; often, in a typically human paradox, the more one attempts to reason with it, the more magnified and intense the opposition becomes. here, i make no attempt to < > reason with it, but choose to ignore it. hostility toward an idea has never constituted a valid argument, and rational argument is our interest here, not the psychology of hostility. in the first passage quoted above from murray’s book, he claims “a realm of objective knowledge about excellence exists.” the category of objective knowledge that he has in view includes both scientific and aesthetic knowledge. in connection with the latter, he is concerned with “aesthetic excellence.” now the usual way in which researchers in aesthetics have approached the matter of aesthetic excellence has been to try to develop criteria or standards in relation to which works of art (here i include music, sculpture, literature, drama, dance, etc.) can be judged on a spectrum from bad to outstanding. this is a reasonable approach to take—to look to the objects of aesthetic creation for relevant standards of excellence. unfortunately that approach has not been successful in establishing the validity of objectively valid judgments concerning beauty. the reason for this failure has been the ease with which it is possible to dispute and reject any proposed set of aesthetic standards that apply to created artistic works. there is nothing beyond the works themselves to appeal to that can serve as a basis for objectivity. it is not so easy, however, to dispute the set of skills that are associated with aesthetic intelligence. the reason this is the case is due to the existence, again, of a “reference group” in terms of which we can identify the skills that are manifested by aesthetically intelligent individuals. a reference group, one that exists independently of the artistic works about we wish to be able to judge objectively, provides us with a separate basis upon which judgment can be formulated and expressed with detachment. objectivity of judgment in this context requires just such a separately of course we are reminded that there is nothing, including even this qualification, that is immune to stubborn disputatiousness. intellectual recalcitrance can perhaps never be eliminated, but, at the same time, recalcitrance, like hostility, is not a rational position, and rational justification is our only concern here. < > available point de repère—it gives us a place to stand, a locus from which judgment can be made about a subject-matter, from outside that subject-matter. and yet we see immediately that to appeal to such a reference group presupposes that we are already in possession of implicit criteria that enable us to choose “appropriate” individuals who are to comprise that reference group. this appears to be manifestly circular, does it not? and in fact it is. but not all circular reasoning is “viciously circular.” sometimes—for logical reasons i will only suggest here and not explain in detail —we cannot possibly get outside ourselves to gain access to that from which our experience internally limits us. this is not as perplexing as it may at first sound: we cannot experience what lies beyond experience; we cannot think thoughts that we are unable to think; we cannot say the unsayable. in these senses—in our experience, in our thought, and in our ability to express ourselves—we are confined to a closed or recurved universe, whose topology, to speak metaphorically, has the shape of a geometrically closed surface in space (e.g., a klein surface): no matter how far we travel, we remain in that space; no matter what we think or experience, we remain subject to the limitations of thought or experience. as inhabitants in such a closed universe, we do not have insurmountable trouble in specifying acceptable criteria in terms of which mathematical or physical truth can be recognized. we have somewhat more trouble specifying acceptable criteria for moral reasoning and conduct, but we can and do accomplish this in the logically circular way in which we can point to recognized spiritual leaders or great humanists and say, “there is an individual with highly developed moral reasoning and conduct.” in the arts, in connection with beauty, our closed universe is somewhat less helpful because it does not lead us directly, in established and commonly accepted ways, to recognize individuals who possess aesthetic intelligence. but we can for those interested in a more technical, less accessible explanation, see bartlett ( ) and bartlett ( b, forthcoming). < > nevertheless begin to formulate the basis for a reference frame in terms of which aesthetic intelligence, and as a result, beauty, are objectively meaningful. a descriptive psychology or phenomenology of aesthetic sensibility, discrimination, and judgment has not been formulated in a manner that can be stated clearly in a way similar to that we have found in connection with cognitive and moral intelligence, for there is today no accepted established reference group of aesthetically intelligent leaders. and yet the defining characteristics of aesthetic intelligence are implicit in our consciousness of those whom we would regard as possessing it. here are some of its main characteristics, which i leave it to the reader to ratify by his or her own cultural experience: to possess a high degree of aesthetic intelligence is to have, in combination, the following set of skills: the skill of sensitivity to the form, structure, detail, and multi- level meaning of a work of art; the ability to discern levels of meaning, complexity, and the successful integration of these in a work of art; the ability to perceive, appreciate, and discriminate a work’s degree of success in communicating its meaning, complexity, and integrity; the ability to recognize and evaluate the artist’s degree of skill in realizing the foregoing accomplishments; a capacity to become absorbed in attention and awareness of what the work expresses; the skill of aesthetic discernment, that is, a breadth of consciousness of the gamut of aesthetic possibility open to whatever art form is involved, coupled with a cultivated, informed capacity to recognize the value of a work on a scale of value. beyond these skills, there is a further essential characteristic required. it is, we might say, a meta-property of the foregoing skills, for it brings together that set of skills within the unity of a distinguishing perspective. i have described this perspective in some detail in a group of previous publications, and so here will only state in a few words the property that is central in defining that perspective. bartlett ( , , a, b). < > what unifies the previous set of skills in an individual possessing aesthetic intelligence is a consciousness and deep-seated appreciation of “higher” and “permanent” realities, realities that have a significance which transcends the “lower” and “transient” world of everyday, mundane living. such higher, permanent realities offer a level of meaning that is perceived by the aesthetically intelligent to be of value in and of itself, and those with aesthetic intelligence immediately recognize this. since our society has generally lost touch with such realities, to the point that the previous paragraph can for some readers be mystifying or meaningless, we may wish for a brief reminder of what they are: to clarify what i mean by ‘permanent realities’, it will be helpful to mention some of the kinds of frameworks of reference from the standpoint of which permanent realities become evident: within the traditional liberal arts, . . . mathematics, art, music, literature, philosophy, and religion were thought to provide such frameworks of reference. in a wide variety of ways . . . these disciplines focused attention on subjects that mattered to individuals whose interests invested them with certain cares. generally these cares involved a concern for realities of a higher order [—that is, realities] that do not change with the passage of time, and do not vary in character when identified by different individuals at different times. terms like ‘logos,’ ‘formal reality,’ ‘transcendental principles,’ etc., were used to refer to them. these subjects of interest to mathematicians, philosophers, and others were asserted to be perennial in that the permanent realities they study constitute a level of discourse and of understanding that is enduring and beyond the effects of the passage of time. (bartlett, a, p. ) this level of discourse and of understanding was thought to be intellectually elevating: in this sense, the artes liberales liberated the mind from its preoccupation with mundane and fleeting human affairs, bringing the mind into contact with higher concerns that, because they are universal and invariant, occupy a plane of reality higher than that of ordinary and routine daily living. < > in the group of publications i mentioned above, i described an increasingly widespread inability in western society to perceive reality under the guise of the transformation that “higher values” make possible. the scholastics called this inability acedia. they associated the word ‘cultus’—that is, ‘culture’—with the permanent realities that are closed off to those whose capacity to appreciate them is impaired by acedia. of course, the word ‘culture’ is today applied enthusiastically and indiscriminately, to “the culture of a business,” “the culture of a sports team,” or “the culture of u.s. kindergarten schools.” but at one time, the word had a specific unitary significance: it pointed to a level of meaning that is both higher than the commonplace and transient, and provided those with the required sensibility access to permanent realities. this “required sensibility” is the meta-property of the skills that define “aesthetic intelligence.” the concept of aesthetic intelligence did not occur to the scholastics, nor did it occur to them to spell out in detail what set of skills, and what defining overall perspective, such intelligence involves. the selection of these defining skills and their meta-property is far from arbitrary, but like the defining skills of cognitive and moral intelligence, the selection made is, in a non-viciously-circular way, dependent upon familiarity with the interests and goals that outstanding aesthetic creation presupposes. as in the cases of cognitive intelligence and moral intelligence, it is of course possible to specify a variety of competing, alternative interests and goals, and as a function of those to propose alternative conceptions of aesthetic intelligence. but in connection with any variety of intelligence there is a need to take into account the reference group consisting of those who express it to an exceptional degree. with cognitive intelligence, this reference group consists—and this is no accident—of individuals who display a set of recognized cognitive skills to an outstanding degree; the same is true of the reference group consisting of those who exhibit high < > functioning moral thought and conduct. when we consider aesthetic intelligence, we similarly do not proceed in a vacuum, but look to those individuals who possess aesthetic intelligence to an exceptional degree. the world of art is rich and multivaried; works of art express a huge range of intent and accomplishment, of simplicity and complication, of design or arbitrariness, of success or failure to communicate. the range and diversity of works of art bear within them, much as do the achievements of mathematics and science, and as do expressions of moral thought and behavior, their own requirements of relevant skills both for their accomplishment and for their appreciation. aesthetic intelligence is therefore not an empty box that can be filled as one pleases: the skills that are required in the human listener, reader, or spectator are spelled out, implicitly, by artistic creations. the skills of aesthetic sensitivity, discernment, absorption, discrimination, breadth of consciousness, and aesthetic valuation are, in fact, prerequisites laid down by works of art themselves. i have given aesthetic intelligence more space in this discussion due to the fact that there is today less evident “aesthetic authority” in connection with this form of intelligence in contrast to the very evident “moral authority” that exists and is well- established in connection with moral intelligence, and in contrast to the “cognitive authority” represented by acknowledged major thinkers, scientists, and mathematicians who exemplify cognitive intelligence. the reference group that provides us with a basis for objective aesthetic judgment does, nonetheless, exist, although the size of the population of that group—consisting of those who can be recognized as clear aesthetic authorities— has diminished in recent decades. that this has happened is an evident consequence of a loss of the sense of fundamental purpose and direction on the part of all of the arts; we get some inkling of this loss by observing the way the term ‘art’ has come to be applied as indiscriminately as the word ‘culture’. < > the phenomenological profile of aesthetic intelligence i have given is intended not as a full and detailed account of the skills that define it, but rather to indicate how it is possible, in relation to a specified set of skills, to recognize the objectivity of beauty in precisely the same way in which morality and truth can be recognized as objective in relation to the skills that define their respective forms of human intelligence. intelligence as a path to objectivity the close relationship between objectivity and intelligence is seldom explored. we take that close relationship for granted when it comes to mathematical and scientific truth; we have, accordingly, developed a well-defined conception of cognitive intelligence as a set of skills which together are essential to the realization and to the understanding of mathematical and scientific truth. in connection with moral reasoning and moral behavior, the human tendency has been to seek for commandments from above or from beyond human experience, moral injunctions which then are believed to be “objective” and therefore non- arbitrary. as i have tried to prove elsewhere, such recourse to “transcendent reality” is a form of conceptual error, a primitive wish “to project” beyond the limitations of human experience in order to persuade believers that what they believe is capable of serving as a compelling objective basis for moral goodness or virtue. the projective wish for transcendent realities has of course brought humanity throughout its history intractable conflicts and great unnecessary suffering. but purely in order to establish the objectivity of morality, the psychological drive to engage in projective belief is unnecessary. in the concept of moral intelligence, we see, for example, bartlett ( , chapter , “the pathology of everyday thought”: § “the delusion of transcendence and human evil”; also a, appendix: “the projection of transcendence”). < > are already in possession of a framework-relative basis for moral objectivity; no more than this is needed. the same is true in connection with aesthetic intelligence. the skills which define that variety of human intelligence provide the necessary basis for aesthetic judgment that is, in parallel with judgments of cognitive truth and judgments of moral goodness, equally objective. . . . we have in this essay in a certain sense turned analysis inward to examine the function of “the eye of the beholder” in establishing objectivity. we have found residing behind the beholder’s eye three distinct forms of human intelligence— cognitive, moral, and aesthetic intelligence—each respectively comprising a pathway to truth, morality, and beauty, and each variety of intelligence providing a basis for the objectivity of its corresponding member of the famous trio. in the process, we have shifted our interest and attention, from truths, moral precepts, and standards of aesthetics, to the corresponding varieties of human intelligence that enable us to recognize and to develop the objectivity of truth, the objectivity of moral thought and behavior, and the objectivity of beauty—each now no longer spelled with a capital letter, as each now serves our human goals not only as an ideal, but as an objective reality. < > references bartlett, steven james ( ). acedia: the etiology of work-engendered depression. new ideas in psychology, : , - . bartlett, steven james ( ). barbarians at the door: a psychological and historical profile of today’s college students. originally published concurrently in the netherlands, in methodology and science, : , , - , and in the u.s., in modern age, : , , - . bartlett, steven james ( a). the loss of permanent realities: demoralization of university faculty in the liberal arts. methodology and science: interdisciplinary journal for the empirical study of the foundations of science and their methodology, : , - bartlett, steven james ( b). the psychology of faculty demoralization in the liberal arts: burnout, acedia, and the disintegration of idealism. new ideas in psychology, : , - . bartlett, steven james ( ). roots of human resistance to animal rights: psychological and conceptual blocks. animal law, , - . electronically re- published october, , by the michigan state university’s detroit college of law, animal law web center, and maintained on an ongoing basis: http://www.animallaw.info/articles/arussbartlett .htm. translated into german: wurzeln menschlichen widerstands gegen tierrechte: psychologische und konceptuelle blockaden. trans. gita y. arani-may. electronically published: http://www.simorgh.de/animallaw/bartlett_ - .pdf. translated into portuguese: raízes da resistência humana aos direitos dos animais: bloqueios psicológicos e conceituais. trans. daniel braga lourenço. brazilian animal rights review (revista brasileira de direito animal), : , july/december, . bartlett, steven james ( ). the pathology of man: a study of human evil. springfield, il: charles c. thomas. bartlett, steven james ( ). normality does not equal mental health: the need to look elsewhere for standards of good psychological health. santa barbara, ca: praeger. bartlett, steven james ( ). the species problem and its logic: inescapable ambiguity and framework-relativity. monograph. published online fall, , by arxiv.org (http://arxiv.org/abs/ . ), in england by cogprints (http://cogprints.org/ /), in france by the centre pour la communication < > scientifique directe’s hal (https://hal.archives-ouvertes.fr/hal- ), and in the u.s. by philsci (http://philsci-archive.pitt.edu/ /). bartlett, steven james ( a). epistemological intelligence. monograph, open access publication, available from philpapers: https://philpapers.org/rec/barei- and the centre pour la communication scientifique directe’s hal: https://hal.archives-ouvertes.fr/hal- . bartlett, steven james ( b). horizons of possibility and meaning: the metalogic of reference. book in progress. bruner, j. s. tagiuri, r. ( ). the perception of people. in lindzey, g. (ed.), handbook of social psychology, pp. - . reading, ma: addison-wesley. eysenck, hans j. ( ). intelligence: a new look. new brunswick: transaction. gardner, howard ( ). multiple intelligences: the theory in practice. new york: basicbooks. gardner, howard ( / ). frames of mind: the theory of multiple intelligences. new york: basicbooks. first pub. . goleman, daniel ( ). emotional intelligence. new york: bantam. guilford, j.p. ( ). the nature of human intelligence. new york: mcgraw-hill. murray, charles ( ). human accomplishment: the pursuit of excellence in the arts and sciences, b.c. to . new york: harpercollins. salovey, peter & mayer, john d. ( ). emotional intelligence. imagination, cognition, and personality, : , - . spearman, charles e. ( ). the abilities of man. new york: macmillan. taft, r. ( ). some characteristics of good judges of others. british journal of psychology, , - . thorndike, e.l. ( ). intelligence and its uses. harper’s magazine, , - . < > about the author steven james bartlett was born in mexico city and educated in mexico, the united states, and france. his undergraduate work was at the university of santa clara and at raymond college, an oxford-style honors college of the university of the pacific. he received his master’s degree from the university of california, santa barbara; his doctorate from the université de paris, where his research was directed by paul ricoeur; and he has done post-doctoral study in psychology and psychotherapy. he has been the recipient of many honors, awards, grants, scholarships, and fellowships. his research has been supported under contract or grant by the alliance française, the american association for the advancement of science, the center for the study of democratic institutions, the lilly endowment, the max-planck-gesellschaft, the national science foundation, the rand corporation, and others. bartlett brings to his research and writing an unusual background consisting of training in clinical psychology, pathology, and epistemology. he is the author and editor of more than books and monographs, and numerous papers and research studies in the fields of psychology, epistemology, and philosophy of science. he has taught at saint louis university and the university of florida, and has held research positions at the max-planck-institute in starnberg, germany and at the center for the study of democratic institutions in santa barbara. he is currently visiting scholar in psychology at willamette university and senior research professor at oregon state university. willamette university hosts a website that provides information about the author and his research, and makes available a large number of his publications in free downloadable from: http://www.willamette.edu/~sbartlet res .. religious studies http://journals.cambridge.org/res additional services for religious studies: email alerts: click here subscriptions: click here commercial reprints: click here terms of use : click here divine maximal beauty: a reply to jon robson mark ian thomas robson religious studies / firstview article / september , pp - doi: . /s , published online: september link to this article: http://journals.cambridge.org/abstract_s how to cite this article: mark ian thomas robson divine maximal beauty: a reply to jon robson. religious studies, available on cjo doi: . /s request permissions : click here downloaded from http://journals.cambridge.org/res, ip address: . . . on sep http://journals.cambridge.org downloaded: sep ip address: . . . divine maximal beauty: a reply to jon robson mark ian thomas robson head of philosophy, st robert of newminster rc school, washington, tyne and wear, ne af, uk e-mail: robson.m @sunderlandlearning.net abstract: in this article i reply to jon robson’s objections to my argument that god does not contain any possible worlds. i had argued that ugly possible worlds clearly compromise god’s beauty. robson argues that i failed to show that possible worlds can be subject to aesthetic evaluation, and that even if they were it could be the case that ugliness might contribute to god’s overall beauty. in reply i try to show that possible worlds are aesthetically evaluable by arguing that possible worlds are maximally rich representations of possible events. i further argue that nothing in god’s being can be aesthetically non-evaluable since god must be maximal beauty – a beauteous maximality which needs no ugliness. finally i show in what sense christ’s heavenly scars can be beautiful. in a recent article, jon robson has challenged my argument that there is a clear contradiction between the notion that god contains within himself all possible worlds and the idea that god is perfectly beautiful. my argument tried to show that a mainstream trend of thought in (analytic) philosophical theology should be rejected. i tried to show that we should not believe that god contains within himself a whole host of possible worlds which he examines, and then selects from as a kind of prelude to creation. in order to make my case against the possible worlds view, i imagined god telling the ‘stories’ of his possible worlds to a pilgrim eager to explore the wonders of the divine mind. some of the stories that god tells are lovely, beautiful, and sublime. the pilgrim is astonished and delighted and awestruck at the beauty of god’s thoughts. other stories tell of all kinds of horrors – there are rapes, murders, and sadistic barbarity beyond the wit of man to imagine. the stories are so full – so excruciatingly minute in their details – that they exactly represent what these events would have been like were they to have been actualized. the pilgrim now realizes that god is not wholly and completely beautiful since many of his thoughts are horrendously ugly. in god’s mind, then, there are possible worlds religious studies, page of © cambridge university press doi: . /s  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . that would transport us to the highest realms of joy, and possible worlds which would make us retch and vomit in horrified disgust. the now worried pilgrim asks if these stories are drawn from any source outside of the mind of god, and god replies that every thought originates from the resources of the divine mind alone; not one inspiration is drawn from elsewhere. i came to the conclusion that a god who contains such ugly stories cannot be wholly and completely beautiful. the moral that i draw from this is that orthodox theists should reject the possible worlds model of the divine understanding, and furthermore concentrate less attention on arguments about god’s power and knowledge. god’s beauty should be more central in philosophical theology, not some kind of weak, background notion that is barely acknowledged. robson has two main arguments against my position, and a parting tu quoque. to begin with, he seeks possible motivations for my conception of god’s beauty (which i characterize as ‘complete and utter beauty’), and suggests that the following principle could serve as my motivation for characterizing god’s beauty in the way that i do: for any object x and any proper part of that object p, if p is ugly then x is not perfectly beautiful. he argues that this principle is implausible since there are many examples of things which are ugly in some of their parts, but nevertheless they are beautiful overall. indeed, the ugly parts may well be needed in order to make the whole thing more beautiful. he gives as an example the ballet the rite of spring. he says, the ballet itself is very beautiful but contains sections, in stravinsky’s complex and dissonant music as well as nijinski’s often awkward and ungainly choreography, which taken by themselves would be very ugly. yet, an attempt to remove those sections, or replace them with some sanitized alternative would somehow miss the point of the work entirely and rob it of its, admittedly complex and somewhat non-standard, beauty. it is obvious, therefore, that many things have parts which are ugly, but the whole can nevertheless be beautiful. the challenge to my position can then be stated: perhaps those possible worlds which are ugly can be part of a beautiful, divine, overall vision. it is an interesting challenge. i think robson is correct in pointing out that my argument was not robust enough to disallow the possibility that god’s beauty could be of such a kind. in other words, i had not adequately guarded my thesis from the notion that god’s beauty might need ugly parts – parts which somehow coalesce together to form a beauteous whole. in order to remedy this, i will try to give reasons for thinking that god’s beauty must be such that no part whatsoever is ugly. i will try to analyse and give voice to the notion that god is maximal beauty – a beauty than which no greater can be conceived.  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . robson’s next argument says that i fail to show that possible worlds are suffici- ently analogous to stories. if this is true and possible worlds are not appropriately analogous to stories, then, a crucial part of my argument is insufficiently supported. to be more precise, i cannot move from the idea that if a story is horrendously ugly then its possible counterpart (the possible world) must be ugly as well. robson suggests that if possible words are aesthetically non-evaluable, then, it could be the case that possible worlds containing such representations as rape, murder and child abuse are not ugly. in reply, i will first argue that god’s stories will be aesthetically evaluable if they are to do the job they are meant to do. they are supposed to make it the case that god knows exactly what he is doing in the creative act. they must, therefore, have sufficient richness of representational content. given enough representational content we have more and more reason for believing that the representations will be aesthetically evaluable. after that, i will focus on the idea of the maximal beauty of the divine. my basic argument will be that nothing in the being of god can be aesthetically non-evaluable, for if there were such regions of aesthetic emptiness god, it seems, could be more beautiful, which contradicts the supposition that he is maximal beauty. if possible worlds are in god in some fashion (which is the usual understanding), then, they must be subject to aesthetic judgement. robson’s final argument says that if i am correct, then, it follows that all classical theists would be in the same boat, not just those who explicitly espouse the notion that god contains within himself all possible worlds. robson says that god’s knowledge of what actual people might do would infect god with ugliness. this ugliness is perhaps not the full-blown, horrendous ugliness of some possible worlds, but it is nevertheless a muddying of the waters of god’s purity. unfor- tunately, although i think this an interesting criticism and well worth answering, it is too large to be dealt with in this article. so we will have to concentrate upon giving answers to robson’s first two objections. i will begin by concentrating on the second of robson’s arguments. then, using the insights gained from the reply to that, move onto a consideration of his first argument. there will then be a short excursion into more theological territory where i discuss the beauty or otherwise of christ’s heavenly scars. are possible worlds analogous to stories? the second of robson’s arguments is our first port of call since it is potentially the most damaging. if robson is right – if possible words are not ap- propriately analogous to stories – then it follows that anything i say about the ugliness of stories will simply be irrelevant as a claim about the aesthetic status of the divine mind. my argument, it would seem, cannot even get off the ground. let us look carefully at what robson says. first, he acknowledges that many writers use the idea of possible worlds being akin to stories as ‘a discursive divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . and pedagogical tool’ but that it is important not to ‘get carried away by these instructive metaphors.’ he goes on to say: ‘stories and possibilities are entities of different kinds and establishing a point about the former will not, without further argument, establish anything about the latter.’ there are, he points out, clear differences between possible worlds and stories. stories, for example, are typically selective. the author of a story selects some events, and not others, for inclusion. one of the stories that i mentioned in my essay is the story of what would happen if the nazi empire had attained supreme dominance over the entire universe and over countless aeons subjected the weak and innocent to torture and mayhem. robson says: ‘it is easy to picture this world as being a piece of alternative history writing gone wrong, a snuff tale filled with gleefully descriptive accounts of the imaginative and gruesome tortures the intergalactic reich imposes on its numerous victims.’ but the possibility i envisage is not a story since it is all- inclusive. everything in such a possible world is included. ‘and i mean’, says robson, ‘everything; every thought that ever crossed the mind of a fourteenth century peasant, every squashed beetle, the exact trajectories of every piece of dust.’ if god were to select from all these other details the ones which included the torture and murder of billions upon billions of innocent people, then we might well complain that his selections were perverse. but possible words are not like that at all. they are maximally inclusive. they cannot, therefore, be stories, or, more precisely, they cannot be seen as being sufficiently analogous to stories for my argument to succeed. robson goes on to point out other disanalogies between possible worlds and stories. possible words ‘are not artefacts, they have no narrator, they are not told in any particular style (primarily because they are not told at all), very many of them . . . lack any reference to the actions of persons or to any relation of con- sequence . . . and they have neither theme or unity of subject matter’. the upshot of all this is: we can judge the beauty or ugliness of stories but we have no idea whether possible worlds are aesthetically evaluable or not. in other words, the analogy between possible worlds and stories is not the kind that allows us to make the leap from one to the other. robson is honest about his own agnosticism on this point: ‘i have no idea how to go about settling the question of whether an abstract entity such as a proposition, or a set of propositions, is itself ugly.’ but, given that we do not know whether or not possible worlds are ugly (or beautiful), we cannot be a position to assert, as i did, that there is a clear contradiction in saying god contains all possible worlds and is, at the same time, completely beautiful. my case against possible words is, therefore, unproven. in reply let me try to show in what way the analogy between possible words and stories is appropriate and allows us to say that if the story is ugly the possible world is ugly as well. robson himself, as we saw, calls the metaphor ‘instructive’. we are looking in what way it is instructive. first let us to look at one of the funda- mental motivations behind possible worlds talk. why do so many theologians  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . and philosophers feel that they want to employ the notion of possible worlds? it seems clear that at least one major reason is that they want god to know exactly what he is doing when he creates the world. if all the worlds that could be actual are laid out in some way in the divine mind, and god can ‘see’ each one of them, or comprehend the possible truths each one contains, then god is in a position to select which one is to be actual. he can reject those whose evil is extreme, and even if, contrary to what leibniz would have us believe, there is no best possible one, god could still make one with an overall positive value. such a god will suffer no surprise or novelty when any particular world is actualized. how do possible worlds provide god with the knowledge of what would come to be were he to actualize that world? the most plausible answer is that possible worlds represent what would happen if that world were to become actual. stories are, of course, similar in this respect. stories, like possible worlds, represent what could be the case. part of the enjoyment and terror of stories is the thought, ‘what if this were to become real?’ as robson has rightly seen, there are important disanalogies between possible worlds and stories. a possible world story, for example, has its representative content increased to a maximal extent. nothing is omitted from this kind of story or representation of what could be. however, all that i need for my argument to work is for the central idea of representation to be shared by both possible worlds and stories. even if there is no theme or unity of content in a possible world maximal ‘story’, there is still representation. we know that certain actual states of affairs are ugly. if the representation (possible world or maximal story) of these states of affairs is rich enough, then it follows that the rep- resentation is ugly as well. we have here the typical possible worlds account of creation: god uses possible worlds in order to find out exactly what worlds would be like if they were to become actual. not one part of the actual world is a surprise to god, says the possible worlds theist. possible worlds or maximal world-books are that to which he looks in order to understand fully what could become actual. it is vitally important that we understand that, under this view, a possible world is not just some vague indicator of what could be; it is not just a gesture towards some amorphous, indeterminate nebula. god, according to this model, knows exactly what the world will be like by looking at its maximal representation. in order to see this more vividly, think of tom. he is a very fastidious, ultra- cautious person, and he wants a building designed and made. being extremely cautious, he asks the architect to give him a plan of the proposed new building, which will specify right down to the last detail what the new building would be like. the architect duly complies and gives tom an immense list of the new building’s properties. it will have seventeen windows, eleven doors, four-foot-high newel posts at the foot of the three grand staircases; it will have rooms of such and such an area and colour, etc. the list is maximal and specifies everything about the proposed house. if possible worlds are like this, or analogous to this, then it might be plausible that they themselves are not beautiful or ugly. it is, after all, divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . only a list. but will tom be satisfied with only a list? he is, you will recall, very fastidious and ultra-cautious. he wants to know exactly what the house will be like. he does not want a vague list; he requires something much richer. the model for the house must be as like the house as is possible; otherwise the actual house might contain surprises. the plan must be maximally representative, not just in specifying everything that the house will contain, but what each thing in that house will be like. tom hates surprises, so he even wants to know what the house will smell like, and feel like to touch! no novelty or serendipity for tom! fortunately, the architect is technically savvy, and writes a computer program using the latest virtual reality techniques. the program hooks up directly into tom’s brain and feeds him the representative content. he can now ‘walk’ around the house, ‘smell’ the house’s scent, ‘feel’ its brickwork. he can scrutinize the house completely, and so nothing in the actual house will now surprise him. it seems that something like this must be true of god. if god is to know exactly what his creating will create, something analogous to virtual reality (maximal representation) will have to be in god’s mind. such a set of images, ‘sights’, ‘sounds’, and ‘smells’ will be ugly if the resultant actual thing will be ugly since in a very strong sense the actual thing is a copy of the virtual or possible thing. god’s ‘stories’ must, it seems to me, be as rich as this; they are so detailed that they are exact representations of the story’s events right down to the last detail. if god’s possible worlds (or maximal stories) are as rich as i have suggested they must be, then many of the ‘stories’ he contains will be extremely ugly. i conclude then that robson’s objection to my argument is unsuccessful. let us turn now to another argument which, as promised, pursues the notion of god’s maximal beauty. my strategy is to move from the specific question of whether or not possible worlds are appropriately analogous to stories. i will argue that, given the usual metaphysics of the christian understanding of possible worlds, they must be the kinds of objects that are capable of being aesthetically judged, and, furthermore, they must be the kind of thing that is beautiful. if any reader is dissatisfied with my first argument, she can concentrate on this one. the issue of whether or not divine maximal possible worlds are appropriately analogous to stories can be completely bypassed. here is the argument in a nutshell: there can be nothing aesthetically non- evaluable in the being of god, and since the god of possible worlds is envisaged as having these possibilia ‘in the region of eternal truths’ which is in the ‘under- standing of god’, they cannot be aesthetically empty. we could (perhaps) get to this conclusion by way of the idea that god is perfectly simple, but again, that would lead us into very complex questions. in that case we would have to explore precisely what is meant by god’s being simple. my route is less complex. i ask this question: can god be anything else but full of beauty? can there be anything which would be neither beautiful nor ugly in the being of god? let me put the question in another way: if god is maximally beautiful can there be anything in  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . god which would leave the spectator (or participator) of (or in) the being of god aesthetically indifferent? to my mind, this cannot be the case. i am not sure that even in the created, finite realm there is anything that is aesthetically neutral. as gerard manley hopkins so memorably said, ‘the world is charged with the grandeur of god.’ interact with the world, and, like foil being shaken, it will shine and spark with joyous exhilaration. a fortiori, there can be nothing in the being of god that does not excite aesthetic appreciation, astonishment, and wonder. robson’s agnosticism about the potential aesthetic non-evaluability of possible worlds is implicitly allowing a kind of aesthetic vacuum into the heart of god, a kind of region where beauty is entirely absent. to be sure, there isn’t any ugliness either, but to entertain the possibility that there is a sort of vapid colourlessness at the heart of the divine being does not seem to do justice to his maximal nature, a maximality which surely must include beauty as well as other attributes like power and knowledge. i am appealing, then, to a kind of principle of plenitude in relation to the beauty of god. he is not just wholly and completely beautiful, but also fully beautiful as well. there can be no ‘part’ of god that is not (so to speak) crammed full of beauty. his aesthetic plenitude is such that he ‘bursts’ and ‘spills’ beauty. it follows from this that if possible worlds are in the regions of god’s understanding then they must also be bursting with beauty. they cannot be aesthetically non-evaluable, which is precisely what robson is allowing as a possibility in his agnosticism about whether abstract entities such as possible worlds can be subject to aesthetic judgement. it seems to me that if god contains possible words then they must have aesthetic value. robson’s argument seems to suggest that god could be partly empty of beauty. it seems to me, however, that any proper conception of the beautiful plenitude of the divine being cannot allow this. this idea will be seen more clearly in the next part of my reply, which attempts to respond to robson’s argument about the relationship between a beautiful whole and its proper parts. could ugly parts be needed in god’s beauty? recall that robson says that the following implausible principle may serve as my motivation for claiming that ugly possible worlds ruin the beauty of god: for any object x and any proper part of that object p, if p is ugly then x is not perfectly beautiful. that this is implausible i am happy to acknowledge. it is implausible since, as robson correctly points out, there are plenty of examples of beautiful wholes which contain ugly parts. indeed, we can say that there are plenty of beautiful wholes that need ugly parts. as we saw, robson uses the example of the ballet the rite of spring. but we need to note that the principle alluded to above is not the principle to which i am committed – i am committed to the idea that divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . god’s beauty is such that it can contain no ugliness. in other words, i agree that the principle that robson suggests could motivate my account is very implausible when it comes to what we might term earthly beauty – the kind of beauty that we, as fallen beings, appreciate and find appealing. the finite beauty we find in the mundane world often needs ugliness to act as a kind of foil. this, i think, points to something deep about our appreciation of the beautiful. we are fallen beings and our appreciation of the beautiful has been radically affected. because of this, any principle that is true of earthly beauty is not necessarily going to apply to the beauty of god. after all, his beauty is not just the best kind around as if his beauty is the undisputed supreme champion at a cosmic beauty contest. his beauty is the beauty that somehow allows or lets other things be beautiful. god’s beauty is ‘off the scale’ so to speak. the principle that robson points to as being implausible is implausible precisely because it begins ‘for any x’. but when talking of god’s beauty we are not talking about ‘any x’, we are talking about the very source of all and consequently the logic or grammar of his beauty must be very different. it seems to me that god’s beauty needs no foil or counterpoint to set it off. it must be unalloyed beauty. now robson could well respond at this point in the following way: ‘all this is grist for my mill. that the grammar of god’s beauty is very different from earthly beauty is precisely the view i have defended in my agnosticism about whether or not possibilia are the kinds of thing that can be subject to aesthetic appreciation. if god’s beauty is so “other” – so radically different – we cannot claim to know what his beauty consists in. if god’s beauty is, indeed, “off the scale” we must be agnostic as to whether it can be subject to any kind of aesthetic “measurability”.’ robson here could be seen as aligning himself with an ancient tradition. god’s reality is hidden by an impenetrable cloud of unknowing. as we ascend the path toward the final mysteries of god’s beauty, speech gives way to silence. i respect this silence, but i do not think that those believers who adopt the typical theistic version of possible world semantics are entitled to be quite so dumbstruck. after all, they say so much about what is going on in god’s mind. god has, it is claimed, whole hosts of perfect and maximal representations of what could be. these perfect representations contain enough representational content for god to know what each actual world will be like right down to the last detail. if this is true, then, as i have argued, we surely can talk about the beauty or otherwise of these representations. robson could, i think, be entitled to agnostic silence, but i don’t think others who espouse divine possible worlds can lay claim to a similar muteness. let me, at this point, try to give the reader a lively sense of what the unalloyed beauty of god must be like by giving two contrasting ‘visions’ of god’s beauty. i am doing this largely because it is so difficult to respond to the kind of agnosticism that robson puts forward in his article. robson, in effect, is saying, ‘for all we know, horrendous and unspeakable horrors might contribute to and  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . make god’s overall beauty even more beautiful.’ this strikes me as massively implausible. part of what i am doing in the following accounts of god’s beauty is to expose and make plain the implausibility. before we start, however, i need to give fair warning that i will talk about parts or aspects of god’s beauty. this goes against an increasing sense of uneasiness i have about the idea that god is not perfectly simple. i find myself more and more persuaded that the notion of the simpleness of god is a crucial formal ‘attribute’ of deity and so talk of parts is, in the final analysis, false. however, given our finite understanding, we can do little but speak as if god’s beauty had parts or aspects, and so that is what i will do in the following contrasting accounts of god’s beauty. what, then, could the beauty of god be like? god’s beauty must (at the very least) inspire a deep attraction, a profound charm and a deep devotion, but at the same time, its purity and holiness would provoke dread and terror. you would be tempted to feel as if you were nothing were it not for the fact that there, in the beauty’s radiance, is a deep love, so intense that you are filled to the brim with the certainty that the source of all regards you as of infinite importance. as you change the direction of your gaze, varied realms of new beauty surprise and delight and stupefy. if you concentrate your attention on one part, it has such endless, breathtaking depth. it is like an infinitely dense fractal – new, more profound, more intricate and more exquisite delights enrapture you as you plunge deeper and deeper. it is a kaleidoscopic wonder of such magnificent intensity. there are beautiful meanings and puzzles, codes and ciphers that delight and send the intellect spinning. there are patterns and harmonies. no part, no matter how minuscule, disappoints – each delights in ways the earth-bound mind could not have dreamt of. there is no ugliness to offset the beauty. there is no need of that. this is god’s beauty after all. our attempts at beauty are tainted. they are ‘bleared, smeared with toil’. our versions of beauty often have to use shade and darkness to bring the light of fullness to the fore, but god’s brightness needs no contrast for its intensity to shine. you laugh with joy, and for the first time, without the slightest trace of sorrow. some aspects of god’s beauty are like music or narrative, and so their wholes unravel chapter by chapter or movement by movement. each part falls seam- lessly into place. some pieces are initially puzzling, and thrill you with delight at their strangeness. then they are seen in their varied and varying contexts and then a new depth of appreciation begins its dizzying, awe-inspiring cycle again. and the delight would be all the more intense given that the root of the experience began in such puzzlement. other parts inspire deep dread and a vertiginous awe. there is what you can only say is a terrible beauty. here we have something too awesome for even the resurrected mind. but god’s beauty is such that, even if you were to explore for all eternity, no part would, to the right-minded, inspire loathing or hatred. no matter where you looked, no matter where you delved, god would be completely and utterly and fully beautiful. divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . contrast this with the idea that robson entertains as a possibility. you are the eager pilgrim in the heaven of god’s beauty. you come across yet another brilliant aspect in the geography of god’s radiance. you change the direction of your gaze and, for a terrible instant, as the profiles of two ranges of mountains come together their lines form a scene of the most terrible and sickening horror and depravity. not one detail is omitted from the nauseatingly ugly scene. nothing is left to the imagination. you are appalled and physically sick. but it is gone immediately you adjust your vision. you see that it is a necessary part of the overall beauty. that mountain range could not exist unless that scene was there as a kind of background. its terrible lines and contours are ‘needed’ for the overall beauty to be as wonderful as it is. you try not to revisit that part of god again, but the memory haunts you as you explore the rest of the divine mind. you are, of course, a little wary. you are never quite sure whether the next scene in the divine mind will require a bit of horror to make it more beautiful. from other now-less-than-eager explorers you learn that there are whole hosts of these scenes representing every horror possible. they tell you that these loathsome parts are eternal, and, indeed, are a necessary part of the very being of god. it seems clear to me that given a choice between these alternative conceptions of the beauty of god, the first one should be preferred. god’s beauty is such that it needs no horror. there are instead awe-inspiring, never-ending oceans and depths of radiance. there may be a terrible beauty (more of this below). but there is no ‘need’ for ugliness. in contrast, robson’s speculations about the relationship between beautiful wholes and their parts allows for the possibility that there are horrors in heaven. i do not see how this is even remotely plausible. i would be extremely surprised to enter heaven to find that god’s overall beauty somehow demanded the existence of local scenes of aesthetic depravity, as if zion needs sodom and gomorrah in order to be beautiful. christ’s heavenly scars what i want to do here is deal with what could be a counter-example to my general position about the aesthetic purity of god. an important problem – at least for a christian theology/metaphysic – is how one could include a theology of the cross within any idea of god’s beauty. the cross is the beauty of the most perfect, self-sacrificial love and it is the utter horror of an innocent being tortured to death. that this innocent is also god incarnate – the very creator of the wood and the iron which racks his body – only serves to augment the horror. so where is the cross in all this – where is the cross in my picture of heaven’s unsullied beauty – a beauty that is supposedly beauty through and through? haven’t i sanitized heaven to the point where it becomes a superficial sentimentality, a place of saccharine pleasure entirely without depth?  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . to examine any theology of the cross is bound to be too large for an article such as this. indeed, it raises a whole host of other questions, not least of which is this: should we understand the cross to be an eternal aspect of the beatific vision? personally, i do not think so. this to my mind eternalizes a moment of horror – the cross, for all its terrible beauty and horror, did not happen for its own sake. it happened to effect something else – salvation. it seems, then, correct to distinguish that which is an essential part of god and that which is contingent upon the way the world is. christ’s sacrifice would not have taken place without a prior act of human rebellion. in a sense then, the cross is ‘external’ to god. of course, christians want to affirm that the love and fidelity which drove christ to the cross are eternal, but whether they want to see the cross itself as a permanent aspect of the deity is a difficult question. we need to limit our ambitions here, and find something potentially ugly which is somehow part of god. let us look, then, all too briefly at this more specific question: christ is in his ascended body in heaven, but his body bears the scars of the events on earth. will these scars somehow ruin the beauty of heaven? countless sermons and hymns say that christ’s heavenly scars are not ruinations or blots. but how can something so ugly be so beautiful? does this accommodation of the ugly with the beautiful tell against my account of god’s complete, utter, and full beauty? does it show that some things really are more beautiful if there are some local aspects which are ugly? my reply is to maintain that ‘ugliness’ can sometimes be transformed. not everything which appears ugly really is so once all is known. christ’s heavenly scars are not just scars. they are testimonies to sacrifice and a love which defies all limits. christ’s scars are, we may say, witnesses to the drama of salvation and its victory. if they were not, if they were just scars, then, they would be ugly; they would only be unsavoury reminders of the vulnerability of the flesh and its inability to heal fully. but the events of the whole salvation drama transform them down to the core. this is not a matter of an ugly part being somehow accommodated into a whole and in doing so making the whole more beautiful. the whole thing must be deeper than that. there a kind of transfiguration going on. perhaps the following account from a different (though related) area would help clarify my thinking about how we should regard the aesthetic status of christ’s heavenly wounds. james kellenberger relates this particularly disturbing practice in the sudan – the live burial of the spear-master. after a set of religious ceremonies an old spear-master is lowered into the ground and the people throw cattle dung onto his prostrate body until he is completely covered except for a small hole. he slowly suffocates to death beneath his prison of excrement. now were a typical westerner to witness this, she would be horrified and appalled. she would, no doubt, think it a morally depraved action, and regard it all as rather horrifyingly ugly. however, there is more going on than merely what we see. divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . kellenberger informs us that the dinka believe that the spear-master is the highest spiritual authority, and that by performing this ‘sacrifice’ of their beloved spiritual master, his spirit will pass through the hole and not be lost by the community. his presence will be preserved and passed on. the spear-master, when he first takes on that position in his society, knows that this will be the way he will die, and chooses the time of death when he is old and frail. cattle dung, for the dinka, is not repulsive, but in their cattle-dependent culture it is a source of ‘curative and restorative powers’. it takes a leap of the imagination to see it through different eyes, but i think we can just about see the event from the perspective of the dinka. they surely do not think that the event is ugly, but perhaps see it as rather beautiful. they certainly find it ethically acceptable, and so might we were we to share the background beliefs that imbue the event with a spiritual significance. on the surface then, we might say, the action is one thing, and appears to have a certain aesthetic quality. on another it is a wholly different thing, and can have a different aesthetic quality, and that once we know this, the initial reaction can be shown to be wrong-headed. we have, so to speak, not seen it with the correct interpretative spectacles on. as i say, beauty is not always on the surface, and what is initially apparently ugly can be shown to be beautiful. now do we have ugly parts which somehow are needed to get the whole thing more beautiful, or is it more subtle, more interconnected than that? do the dinka see a murder, which is then transformed into a sacrifice? do the dinka see aesthetically depraved parts mixed with some beauty and see that the ugliness helps to make the whole aesthetically better? i think not. there is a transfiguration happening, a fundamental change in the whole and not just at the level of parts. it is important to realize that i am not advocating a kind of subjectivity about beauty here. i think that what the dinka are doing is, in reality, objectively ugly, and, of course, ethically unacceptable. the dinka are wrong in almost all their background beliefs, and so what is happening is not actually a real transfiguration. it is only an apparent one. there is, of course, a danger in this approach to beauty. might we not re-describe everything – even the aesthetically and outrageously appalling – in such a way that it is imbued with a kind of allure? yes, we can. this is probably why we do so many wrong things. we re-describe them to ourselves so that they take on a veneer of respectability. and there is a similar danger in the theological context too. we sanitize horror and make it kitsch. much religious imagery sometimes seems like that. however, it seems to me that, even given the dangers of misdirected re-description, we can see the central point that beauty and ugliness are not just surface phenomena. there will be deep beauty in heaven, perhaps, in some ways, a terrible beauty, but not horrors which are horrors through and through. we must remember that if possible world talk is true there will not be just a few eternally discordant notes, not just a few ungainly dances,  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . but whole hosts of horrors right at the very heart of heaven. these horrors remain in god for all eternity. my view is that this is not so, and we must reject the notion that god contains possible worlds. conclusion a summary of the argument might be helpful. robson argues that possible worlds are not sufficiently analogous to stories for us to be confident whether they are aesthetically evaluable. i had two arguments here. one said that if possible worlds have enough representational content for god to know exactly what he is doing in creation, then possible words must be, in some sense, copies of actual worlds. if a possible world or maximal story represents ugliness, the represen- tation must be ugly. otherwise god won’t know what could be. my next reply said that possible worlds must have an aesthetic status since there could be nothing aesthetically neutral in the being of god. robson also said that, for all we know, it could be the case that god’s beauty was such that it needs ugly parts. after all, this is true of many beautiful works of art such as the rite of spring. i argued that this might be true of earthly beauty, but god’s beauty cannot be like that. god must, i reiterated, be completely, fully, and wholly beautiful. finally i considered a possible counter-argument within christian theology. doesn’t the resurrected lord have scars in heaven? if so, aren’t there ugly things in heaven? i countered by saying that christ’s scars are not ugly. they are transfigured to the core by his free self-sacrifice and his desire for our salvation. references adams robert () ‘theories of actuality’, in loux (), –. ayres, lewis () nicaea and its legacy: an approach to fourth-century trinitarian theology (oxford: oxford university press). balthasar, hans urs von () theodrama: theological dramatic theory, iv: the action (san francisco: ignatius press). begbie, jeremy s. () theology, music and time (cambridge: cambridge university press). () ‘beauty, sentimentality and the arts’, in treier et al. (), –. burrell, david b. () knowing an unknowable god (notre dame in: university of notre dame press). () ‘creatio ex nihilo recovered’, in janet soskice (ed.) creatio ‘ex nihilo’ and modern theology, modern theology, special issue, , –. craig, william lane () the only wise god: the compatibility of divine foreknowledge and human freedom (eugene or: wipf and stock publishers). () ‘the middle knowledge view’, in james beilby & paul eddy (eds) divine foreknowledge: four views (downers grove: intervarsity press), –. currie, gregory () narratives and narrators (oxford: oxford university press). divers, john () possible worlds (london: routledge). gaines, simon francis () will there be free will in heaven? (london: continuum). hart, david bentley () beauty of the infinite (cambridge: eerdmans). herman, bruce () ‘wounds and beauty’, in treier et al. (), –. hopkins, g. m. () the poems of gerard manley hopkins, w. h. gardner & n. h. mackenzie (eds) (oxford: oxford university press). divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . kant, immanuel () [] critique of judgement, james meredith (tr.) (oxford: oxford university press). kekes, john () the morality of pluralism (princeton: princeton university press). kellenberger, james () moral relativism, moral diversity and human relationships (university park pa: pennsylvania university press). kilby, karen () balthasar: a (very) critical introduction (grand rapids mi: eerdmans). leibniz, g. w. () [] monadology, george montgomery (tr.) (la salle: open court publishing). loux, michael () the possible and the actual (new york: cornell university press). nichols, aidan () no bloodless myth (washington, dc: catholic university of america press). () a key to balthasar: beauty, goodness and truth (oxford: blackwell). plantinga, alvin () ‘transworld identity or world-bound individuals’, in loux (), –. () ‘actualism and possible worlds’, in loux (), –. robson, jon () ‘do possible worlds compromise god’s beauty? a reply to mark ian thomas robson’, religious studies, , –. robson, mark ian thomas () ontology and providence in creation: taking ex nihilo seriously (london: continuum). () ‘possible worlds and the beauty of god’, religious studies, , –. treier daniel, mark husbands, & roger lundin (eds) () the beauty of god: theology and the arts (downers grove: intervarsity press). walford, john e. () ‘the case for a broken beauty: an art historical viewpoint’, in treier et al. (), –. walton, kenneth l. () ‘categories of art’, philosophical review, , –. notes . robson (). and jon robson’s reply: robson (). . i presumed throughout the article that possible worlds are in god – in his understanding. there is no separate plenum from which god draws his inspiration. i take it that this is a part of the normal, theistic understanding of the relationship between possible words and the being of god. . robson (), , agrees that there should be a redistribution of emphasis. . ibid., . . i think at least the beginnings of an answer lie in the metaphysics of modality i present in robson (). we might, for instance, ask the question of who ‘owns’ the possibility that, say, the actual jack the ripper think one more ugly thought. i think god is thinking about things which are ‘external’ to his mind. i do not believe he is internally representing anything here, but thinking about actual things and their real possibilities. the intentional object of god’s thinking is the real jack the ripper, his inclinations, his habits, and his psychological makeup. these are real things which are always understood to be outside god in some way or other – at least if we are not pantheists. . robson (), . . ibid. . ibid., . . robson (ibid.) cites currie () on these criteria. . robson (), . . it might be helpful to remind ourselves of the pervasiveness of the metaphor of possible worlds being stories. we have robert adams (), plantinga (), and plantinga (). john divers (), –, calls this position book-realism and adds the following philosophers to our list: jaakko hintikka, andrew roper, and richard jeffrey. . william lane craig argues that there are many problems with the visualization metaphor, and prefers an account where god simply knows truths. he contrasts what he calls perceptualist models of god’s foreknowledge with conceptualist accounts, and prefers the latter. see craig (), –, and craig (), –. i think that god needs something at least analogous to pictures or images if his idea of, for example, a yellow ball is going to have any semantic content. how will god know what hue adam’s skin will possess if he does not have some kind of image? see robson (), –. . the idea of actualization is weird. however, we have grown accustomed to its strangeness, and hardly think it worthy of comment. one of its many ambiguities is this: when god actualizes a world, is it that  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . very divine idea that is made real, or is the possible world a kind of maximal model for the world that comes to be? are possible worlds themselves made real, or are they complete models for the real? the whole force of the word ‘actualized’ seems to favour the former reading, but then we have problems. if we do not want to be pantheists, we must say that in some sense the actualized world is ‘outside’ the divine mind, and so in actualization god is literally losing a bit of his mind. even the most enthusiastic advocate of kenosis would blanch at that idea. i argue that the alternative idea of copying has unfortunate theological implications in robson (), –. however, others see the contrast between pantheism, emanation, and creation to be more nuanced than this simple sketch suggests. see burrell (). . actually we might question the strict accuracy of this statement. possible worlds are understood to be logically prior to their actual counterpart. but the verb ‘represent’ implies that the logical priority is the other way round. this seems to me another confusion surrounding possible worlds talk. see robson (), n. . . now i have argued elsewhere (ibid., – and –) that this seems to imply that the actual world becomes only a kind of copy or perfect imitation of the possible world. in other words, the possible world which is selected for actualization is copied out and made real. of course, many advocates of the possible world view would prefer to use more exotic vocabulary instead of the much blander and clearly much less exciting idea of ‘copying’. so they might say a particular possible world ‘obtains’, while those which are not realized by god ‘do not obtain’. those that are not selected remain as mere ‘unactualized’ (as opposed to ‘actualized’) possible worlds. i think it up to the leibnizians to show how ‘actualization’ or the mysterious process of ‘obtaining’ is different from copying. but, in doing so, they must show how it is possible for a model (the possible world, maximal state of affairs, or whatever) to provide god with a complete and rich enough understanding of that world without it being a copy of its actual counterpart. . the rest of the argument is this: since it is obvious that not all possible worlds will, in fact, be beautiful our only option is to reject the idea that there are possible worlds in the mind of god. . the quotations are from the originator of the possible worlds idiom leibniz () [], sect. , p. . . hopkins (), ‘god’s grandeur’. hopkins seems to be suggesting that god’s beauty in the world is often underneath the surface, so to speak. the world is charged with the grandeur of god, rather than actually sparking. we must shake the foil. we must tread the olives to extract the oil, and without the encumbrance of shoes, directly feel the ooze of its richness. of course, hopkins also knows that the world can be very ugly as well. grim testimony to this can be found in his dark sonnets. . on an autobiographical note, i can report that when i wrote the original article an early draft contained an attempt to capture some of the beautiful stories that wisdom could tell her pilgrim. these stories were meant to capture the merest glimpse of the noble grandiloquence and unquenchable beauty of the divine mind. to my vanity’s chagrin, i quickly found out that this is an impossible task. my ‘beautiful’ stories became sentimental, inane, and sickly sweet. certainly i could not write a story that was completely and wholly beautiful and at the same time prevent it from being cloying and indeed rather ugly. it was much easier to write tales of perverse horror. as we all know, this problem has assailed far greater minds: milton’s satan is a lot more exciting, glamorous, and beautiful than the spock-like logician that milton has playing the role of god. . robson makes this kind of criticism of my position in correspondence. . see burrell (), –. see ayres (), ch. . the term ‘simpleness’ is one which burrell prefers over the more usual ‘simplicity’. . these are meant to be minimum conditions of the divine beauty. i am not attempting to describe the fullness of the actual beatific vision. words will surely not be enough. . interesting questions arise here about the relationship between freedom and the beatific vision. can the saint in heaven avert her gaze from the contemplation of the godhead? the orthodox view is that the heavenly saints are impeccable or incapable of sin, which suggests that they cannot but look upon the glory and beauty of god. these issues are pursued by gaines (). . hopkins (), ‘god’s grandeur’. . see begbie () for his argument that some kind of analogue of temporal succession is an essential part of our conception of god. divine maximal beauty: a reply to jon robson  http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . . orthodox believers in divine possible worlds usually subscribe to the idea that whatever is possible is necessarily possible. . an excellent essay which deals with exactly these themes is begbie (), –. see also herman (). herman’s ideas are especially interesting in this context. walford () has many specific examples of how art tries to represent the world’s fallen nature. . hans urs von balthasar tries to accommodate two competing currents in his thought here. he wants two apparently contradictory things to be simultaneously true. the event of the cross is entirely the act of god. it is not a mere adjunct to the deity – as if it were ‘accidental’ in my sense. but he also wants it to be because of our presumably contingent actions. this passage seems to capture this tension well: ‘the action taking place between heaven and earth is not one-sided – for example, the mere pouring out of bowls of wrath from above – for where does the lamb’s supratemporal wound come from, if not from his destiny on earth?’ (balthasar (), ). note the idea of a supratemporal wound as if the christ’s wounds are a timeless aspect of the godhead, but also the notion that somehow it is contingent upon the way the world is. overall, however, balthasar’s theology sees the cross as eternal. it is taken into the very life of the trinity. christ is, he says, eternally infinitely distant from the father. see kilby (), –. see her very penetrating comments on balthasar’s views on the value of suffering (ibid., –). balthasar’s idea of theodrama has been a central inspiration in the ideas that follow. however, what i say here should not be read as any kind of interpretation of his work. such a task is well beyond the limits of a short essay, and well beyond the limits of my scholarship. for a short overall account of balthasar see nichols (). for more detail see nichols (). . d. z. phillips gives an account in one of his lectures of a poem – it is a splendidly patriotic poem and gives its readers immense pleasure in the beautiful way it captures the spirit of loyalty to kin and country. it turns out one day that we find the author was a traitor to his own country. now what was beautiful and moving becomes ugly and treacherous. it is possible, therefore, that there could be two identical ‘patriotic’ poems with the same words and cadence, etc. a was written by a patriot and b was written by a traitor. it seems plausible to assume that a would be beautiful, while b would be ugly. (think of two helens of troy identical in every facial feature – one is a natural beauty, the other made by a kind of mengelean plastic surgery where each skin graft came from unwilling donors.) it seems natural to say that b has the superficial appearance of beauty without actually being beautiful. in order to counter this, one could say that the origin of a work of art is irrelevant. however, it does seem part of what i mean by beautiful that we must, so to speak, delve beneath the surface. after all, are not many evil things superficially lovely and attractive and beautiful? if they are not, why do people feel such attraction for them? (in his superb beauty of the infinite (), –,  hart seems to imply that beauty is always a surface phenomenon. i think that beauty – real beauty – has to be all the way down.) kant would disagree with the idea that beauty relies upon things external to the object. he would claim that a pure judgement of beauty would distinguish between my disapproving of the existence of such a face (or such a poem) with my disinterested appreciation of its beauty. see kant () [], pt. i, sect. , § . presumably he would think both helens of troy equally beautiful, and both poems inspiring. see walton (), –, for a defence of the view that aesthetic appreciation depends on more than the physical attributes of the artwork itself. i thank jon robson for the walton reference. . kellenberger (), –. kellenberger is defending his principle of ascent which says: ‘ascending values tend towards universality: as the level of abstraction of a moral value increases, the breadth of its application and acceptability increases’ (ibid., ). . ibid., . kellenberger is here quoting from kekes (), –. . think of such initially repulsive christian phrases like ‘washed in the blood of the lamb’, ‘his body broken for you’, etc. christians find such phrases beautiful. . kellenberger (), –, sees this danger. . for example, in that bestseller of the late nineteenth century, quo vadis? by henryk sienkiewicz, there are such graphically long and detailed descriptions of the executions and the tortures that the christians endure that it becomes disturbing. there is a kind of unsavoury celebration of the pain and suffering. (however, we must not lose sight in our world of anaesthetics and pain-killers that other times have had to endure more pain. the edification of pain might have been a balm that they needed.)  m a r k i a n t h o m a s r o b s o n http://journals.cambridge.org http://journals.cambridge.org downloaded: sep ip address: . . . . what is the alternative to possible worlds? i would say that possibility is not determinate. there are no things in possibility like possible worlds or possible hitlers. possibility is not, we might say, composed of atoms. this is the main modal claim which i attempt to pursue in robson (). . i am very thankful to jon robson for responding so clearly to my article, and for his generous comments on earlier drafts of this essay. he made me see things more clearly. i am also thankful to phil robinson for his perceptive criticisms and comments. fr tony currer has made valuable contributions in discussions over christ’s scars. his knowledge of christian art has helped me a lot. divine maximal beauty: a reply to jon robson  http://journals.cambridge.org doi: . /j.neuroimage. . . www.elsevier.com/locate/ynimg neuroimage ( ) – brain correlates of aesthetic judgment of beauty thomas jacobsen, a,* ricarda i. schubotz, b lea höfel, a and d. yves v. cramon b a biocog-cognitive and biological psychology, institute of psychology i, university of leipzig, seeburgstrasse - , leipzig, germany b max planck institute of human cognitive and brain sciences, department of neurology, leipzig, germany received april ; revised june ; accepted july available online august functional mri was used to investigate the neural correlates of aesthetic judgments of beauty of geometrical shapes. participants performed evaluative aesthetic judgments (beautiful or not?) and descriptive symmetry judgments (symmetric or not?) on the same stimulus material. symmetry was employed because aesthetic judg- ments are known to be often guided by criteria of symmetry. novel, abstract graphic patterns were presented to minimize influences of attitudes or memory-related processes and to test effects of stimulus symmetry and complexity. behavioral results confirmed the influence of stimulus symmetry and complexity on aesthetic judgments. direct contrasts showed specific activations for aesthetic judgments in the frontomedian cortex (ba / ), bilateral prefrontal ba / , and posterior cingulate, left temporal pole, and the temporoparietal junction. in contrast, symmetry judgments elicited specific activations in parietal and premotor areas subserving spatial processing. interest- ingly, beautiful judgments enhanced bold signals not only in the frontomedian cortex, but also in the left intraparietal sulcus of the symmetry network. moreover, stimulus complexity caused differential effects for each of the two judgment types. findings indicate aesthetic judgments of beauty to rely on a network partially overlapping with that underlying evaluative judgments on social and moral cues and substantiate the significance of symmetry and complexity for our judgment of beauty. d elsevier inc. all rights reserved. keywords: evaluative judgment; aesthetic judgment; descriptive judg- ment; symmetry; aesthetics; fmri introduction what are the brain correlates of aesthetic judgment? previous studies have investigated effects of attractiveness and preference by presenting faces (aharon et al., ; kampe et al., ; o’doherty et al., ) or works of art (kawabata and zeki, ; vartanian and goel, ) and yielded evidence for a role of reward-related subcortical and limbic areas. however, these - /$ - see front matter d elsevier inc. all rights reserved. doi: . /j.neuroimage. . . * corresponding author. fax: + . e-mail address: jacobsen@uni-leipzig.de (t. jacobsen). available online on sciencedirect (www.sciencedirect.com). approaches focus on the particular valences of judgments, e.g., by parametric manipulation of levels of attractiveness or by direct comparison of beautiful versus ugly or neutral pictures. in contrast, none of these studies aimed at identifying the network of aesthetic judgment per se. aesthetic judgments can be considered a subset of evaluative judgments such as those made on social, religious, or moral cues. evaluative judgments as in contrast to descriptive ones were reported to engage frontomedian areas around brodmann areas (ba) and mostly together with posterior cingulate cortex or precuneus as well as ventral prefrontal cortex around ba / (cunningham et al., , ; greene et al., , ; johnson et al., ; moll et al., , ; zysset et al., ). it appears plausible to hypothesize aesthetic judgments to engage a similar cerebral network. however, since all considered studies focused on the social or moral evaluation of persons or actions, it remains a fully open issue whether also not-social and non-moral evaluation on abstract entities call for the same network. the present fmri study used novel, abstract graphic patterns as stimulus material (jacobsen and höfel, ) to isolate the neural correlates of aesthetic judgments of beauty (jacobsen and höfel, ; jacobsen et al., ). importantly, these stimuli afforded judgments that could not be based on attitudes (petty et al., ) or other memory representations. when using faces or works of art as objects of aesthetic judgment, it cannot be excluded that attitudes like, e.g., financial interests (in case of works of art) or attractiveness (of faces) partly confound identified brain areas. indeed, an old issue in aesthetics questions whether the evaluation of beauty can be independent of desire, i.e., ‘‘disinterested’’ (kant, ). this is particularly critical as those factors should also affect brain correlates of self-reflection as outlined above. a further confound with a similar effect could result from episodic or semantic memories (zysset et al., ). participants performed two judgment tasks and an additional forced choice task. they had to judge either whether a stimulus was beautiful or not (aesthetic judgment task) or whether it was symmetric or not (symmetry judgment task). in many individuals aesthetic judgment is found to be ruled by symmetry (e.g., jacobsen and höfel, ). therefore, we expected both the symmetry judgment task and the aesthetic judgment task to trigger http://www.sciencedirect.com t. jacobsen et al. / neuroimage ( ) – an assessment of symmetry. in contrast, differences between the brain correlates of aesthetic judgment and symmetry judgment should be solely due to differences of judgment processes per se. note that stimuli also controlled for effects of symmetry. likewise, stimulus complexity has a significant influence on aesthetic judgment of beauty (eisenman, ; berlyne, ; jacobsen and höfel, ). this factor, again, has not yet been controlled for in studies using faces and works of art as stimulus material, where it also may elude control. while symmetry was a dichotomous stimulus property in the present approach, stimulus complexity was varied as a scalar property. our design therefore allowed to additionally analyze the parametric influence of perceptual complexity on the considered brain networks. materials and methods participants fifteen right-handed, healthy young volunteers ( male; age range, – years; mean age . years) participated in the study. none of them had received professional training in the fine arts or participated in a similar experiment before. participants had normal or corrected-to-normal visual acuity and no known neurological condition. after being informed about potential risks and screened by a physician of the institution, subjects gave informed consent fig. . exemplary trials for both judgment tasks (middle) and for the control condi ( s) and a picture presented at screen center for . s. participants were asked to pr asked to decide whether or not the presented stimulus was beautiful (aesthetic ju were asked to press the left button for arrow pointing left and the right button for row) and complex (lower row) stimuli which are either symmetric (right column) before participating. the experimental standards were approved by the local ethics committee of the university of leipzig. data were handled anonymously. material black and white patterns from jacobsen and höfel ( , ) were used for aesthetic (aj) and symmetry (sj) judgment conditions in this experiment ( for the practice trials, in the main experiment). each consisted of a solid black circle ( . cm in diameter) showing a centered, quadratic, rhombic cutout and – basic graphic elements (small black triangle) arranged within the rhomb according to a grid and resulting in a graphic pattern. the basic elements were arranged such that geometric figures like triangles, squares, rhombuses, horizontal, vertical, or oblique bars were created. using this approach of basic elements, the overall luminance was identical for all stimuli. half ( ) were sym- metrical, i.e., one mirroring operation given four possible symmetry axes was sufficient to detect symmetry. the other half of the stimuli was clearly not symmetric. fig. shows examples of the material. the following features of the patterns were extracted for use in the judgment analysis: mirrored at one axis (one operation sufficient), mirrored at two axes (each one of two possible operations sufficient), regular composition, number of elements, horizontal or vertical bars, large horizontal or vertical bars, small tion (top right). a variable jitter time of . – s was followed by a task cue ess the selected response button while the picture was presented. they were dgment) or symmetric (symmetry judgment); in the control condition, they arrow pointing right. stimulus examples (bottom left) depict simple (upper or not (left column). t. jacobsen et al. / neuroimage ( ) – horizontal or vertical bars, oblique bars, large oblique bars, small oblique bars, squares, large squares, small squares, rhombuses, large rhombuses, small rhombuses, triangles, large triangles, and small triangles. these were considered to be perceptual cues that could be used by the participants in deriving their judgments. accordingly, the features were employed in the judgment analysis, i.e., they were introduced as predictors in the multiple regression analysis (jacobsen, ; jacobsen and höfel, ). for the control condition (cc), two stimuli (hereafter: arrow patterns) were employed which exactly matched the properties of the judgment stimuli. in these stimuli basic graphic elements were clustered to show an arrow pointing either left or right. procedure this study was conducted in two parts. the first part, the aesthetic threshold test (see below), served to select participants with an aesthetic threshold appropriate for the stimulus set. aesthetic threshold test for the individual beholder, a stimulus needs to have certain properties, in order to elicit aesthetic appreciation. it must exceed the aesthetic threshold (fechner, ). the participants were asked to judge graphic patterns on any number out of six - point rating scales (� to + ), depending on which scales they considered sensible. three of these scales were descriptive (round–angular, small–large, not symmetric–symmetric) and three evaluative in character (not harmonic–harmonic, not beautiful–beautiful, not interesting–interesting). arguably, the beauty scale was only chosen if a given pattern exceeded the aesthetic threshold. participants of the fmri experiment were selected on the basis of this test: at least two of the three exemplary patterns that were used in the main experiment had to be judged on the aesthetic scale. the aesthetic threshold of the participant (value on mixed subject–object mds model) had to be lower than the value of those three patterns. fmri experiment the paradigm comprised two experimental conditions (aj, sj), one control condition (cc) and one resting baseline condition (rc) (fig. ). three hundred trials were presented overall, with trials per experimental condition and per control and resting condition. conditions were presented in random order (mixed-trial design). background color of the screen was light gray throughout the experimental session. within each trial of each condition, the screen-centered presentation of the target stimulus (visual angle of . -) lasted . s including response time and was preceded by a - s verbal task cue; stimulation was followed by an intertrial interval that lasted . s. to enhance the temporal resolution of the blood oxygenation level-dependent (bold) signal, variable jitter times of , , , or ms were inserted at the beginning of each trial. stimuli (except arrow patterns) were pseudo-randomly assigned to the experimental conditions aj and sj, that is there was no item repetition (höfel and jacobsen, ). assignments were counterbalanced across participants. the type of judgment and symmetry status of the stimuli were fully crossed. participants were asked to judge the patterns with regard to symmetry and aesthetic value contingent on the task cue, answering the question ‘‘is this pattern symmetric?’’ in the former case and ‘‘is this pattern beautiful?’’ in the latter. they were instructed to press one of the two response buttons (‘‘yes’’ or ‘‘no’’) when they had decided but still while the stimulus was presented (maximal response time . s). participants were randomly assigned to two possible response key assignments (no/yes, yes/no). in cc, participants were presented arrow stimuli pointing equiprobably either to the left or to the right. participants were asked to press the corresponding response buttons (left button for arrow pointing left, right button for arrow pointing right). in rc, no cue or stimulus was presented but only a black screen-centered fixation cross. participants were instructed to fixate the cross and to wait for the next trial. data acquisition participants were instructed before the mri experiment. before the experimental session, during acquisition of the anatomical data sets (see below), a block of twenty practice trials was administered using ten symmetric and ten not symmetric patterns. in the mri session, subjects were supine on the scanner bed with their right index and middle finger positioned on the response buttons. to prevent postural adjustments, the subjects’ arms and hands were carefully stabilized by tape. in addition, form-fitting cushions were used to prevent arm, hand, and head motion. participants were provided with earplugs to attenuate scanner noise. imaging was performed at t on a bruker medspec / system equipped with the standard birdcage head coil. twenty-two axial slices (field of view mm; � pixel matrix; thickness mm; spacing mm) parallel to bicommissural line (ac pc) were acquired using a single-shot gradient echo-planar imaging (epi) sequence (echo time, ms; flip angle, -; repetition time, s) sensitive to blood oxygenation level-dependent (bold) contrast. a set of two- dimensional ( d) anatomical images was acquired for each subject immediately before the functional experiment, using a modified- driven equilibrium fourier transformation (mdeft) sequence ( � pixel matrix). in a separate session, high-resolution whole-brain images ( slices and mm slice thickness) were acquired from each subject to improve the localization of activation foci using a t -weighted three-dimensional ( d) segmented mdeft sequence covering the whole brain. behavioral data analysis in the judgment analysis, the judgment values were entered into a constrained stepwise multiple regression as the criterion along with the stimulus features (cues, see above) as predictors. the cue explaining most of the criterion variance was entered into the model first. other cues, providing incremental explanation of variance, were entered, if they did not show a substantial cue–cue correlation with already entered cues (r < . ) and yielded a beta weight of . or more reflecting incremental explanation of variance (jacobsen, ). fmri data analysis the mri data were processed using the software package lipsia (lohmann et al., ). functional data were corrected for motion using a matching metric based on linear correlation. to correct for the temporal offset between the slices acquired in one scan, a sinc-interpolation based on the nyquist shannon theorem was applied. a temporal high-pass filter with a cutoff frequency of / hz was used for baseline correction of the signal and a spatial gaussian filter with . mm fwhm was applied. to align the functional data slices with a d stereotactic coordinate reference t. jacobsen et al. / neuroimage ( ) – system, a rigid linear registration with six degrees of freedom ( rotational, translational) was performed. the rotational and translational parameters were acquired on the basis of the mdeft and epi-t slices to achieve an optimal match between these slices and the individual d reference data set. this d reference data set was acquired for each subject during a previous scanning session. the mdeft volume data set was standardized to the talairach stereotactic space (talairach and tournoux, ). the rotational and translational parameters were subsequently transformed by linear scaling to a standard size. the resulting parameters were then used to transform the functional slices using trilinear interpolation, so that the resulting functional slices were aligned with the stereotactic coordinate system. slice gaps were interpolated to generate output data with a spatial resolution of � � mm. the statistical evaluation was based on a least squares estimation using the general linear model (glm) for serially autocorrelated observations (random effects model; friston, ; friston et al., a,b; worsley and friston, ). the design matrix was generated with a synthetic hemodynamic response function and its first and second derivative. brain activations were analyzed in an event-related design time locked to stimulus onset. the model equation, including the observation data, the design matrix, and the error term, was convolved with a gaussian kernel of dispersion of s full width at half maximum to deal with the temporal autocorrelation (worsley and friston, ). in the following, contrast images, i.e., estimates of the raw score differences between specified conditions, were generated for each participant. the single-participant contrast images were then entered into a second- level random effects analysis for each of the contrasts. the group analysis consisted of a one-sample t test across the contrast images of all participants that indicated whether observed differences between conditions were significantly distinct from zero (holmes and friston, ). subsequently, t values were transformed into z scores. to protect against false-positive activations, only regions with z score > . ( p > . ; uncorrected) and with a volume > cubic mm ( contiguous voxels) were considered. all reported activations survived a threshold corresponding to p > . (corrected for multiple comparisons) at the cluster level. table paramorphic individual case models (rows: participant nos. – ) and model for th a b c d e f g � . � . . . � . . � . . . � . . mean . standardized regression coefficients and multiple regression coefficients (r) are s included in at least one model. most important predictors are in bold font. abbreviations: a = number of elements; b = horizontal or vertical bars; c = larg triangles; g = squares; h = large squares; i = small squares; j = rhombuses; k = results behavioral results judgment analysis table gives the paramorphic individual case models for the participants as well as the model for the group average data. standardized regression coefficients and multiple regression coefficients (r) are shown. the following predictors were included in at least one of the models: number of elements (i.e., a measure for complexity, see fmri analysis), horizontal or vertical bars, large horizontal or vertical bars, oblique bars, large oblique bars, triangles, squares, large squares, small squares, rhombuses, small rhombuses, mirrored at one axis, and mirrored at two axes. no other predictor was included in a model. in addition to these paramorphic individual case models, a group model derived from the mean judgment values for each picture was computed using the same method. for one of the participants, no informative model could be derived. as predicted, symmetry was found to be the most important stimulus property determining participants’ aesthetic judgments. in general, participants showed agreement that symmetric and regular pictures were more beautiful than the others. the group model also reflected this fact. additionally, the individual case models revealed consistent inter-individual differences. twelve partici- pants used symmetry cues as the most important stimulus property determining beauty in a positive direction. one of them relied on symmetry cues as the sole substantial factor influencing his judgments. for them, a symmetric pattern was more beautiful. moreover, individual beta weights of symmetry cues ranged from . to . revealing considerable variation of cue use, that is the importance of symmetry cues for individual judges differed. these inter-individual differences were leveled by the group model. hence, detailed capturing of individual judgment policies provides a more thorough account of aesthetic judgment policies for these stimuli. at the group level, the number of elements in a pattern, a measure for complexity, accounted for the second-most amount of e group average data (last row: mean) as computed in the judgment analysis h i j k l m r . . . . . . . . / . . . . . . . . . . . . . . . . . . . . . . . . . hown. columns show all predictors (a–m, abbreviations as given below) e horizontal or vertical bars; d = oblique bars; e = large oblique bars; f = small rhombuses; l = mirrored at one axis; m = mirrored at two axes. t. jacobsen et al. / neuroimage ( ) – variance. one of the participants relied on this predictor as the sole substantial factor influencing his judgments. three participants considered a larger number of elements in a pattern more beautiful. conversely, one participant had the opposite strategy. to him, patterns with fewer elements were more beautiful. one participant relied on a shape cue for the judgment. this participant found patterns with rhombuses more beautiful than other patterns. this predictor was found to be the most important predictor, followed by number of elements. a number of stimulus features (e.g., small triangles or small oblique bars) were not used by the participants to derive their judgments. participants revealed differences in linear predictability. multiple r’s ranged from . to . , that is, a range of explained judgmental variance from % to %. the group model showed . % of linearly explained variance, thus leveling the inter- individual differences and hiding that fact. averaging procedures treat individual differences as noise and therefore cancel them out which was not adequate for the present data. furthermore, differences in explained variance are typically interpreted as an index of strategy use (stewart, ). participants with a high linear predictability used systematic judgment strategies, while linearly unpredictable judges most likely employed highly config- ural cue combinations (brehmer and joyce, ; cooksey, ). behavioral performance . % of all symmetry judgment responses were correct. there were . % non-responses and . % of the given answers were erroneous. aesthetic judgment responses showed . % non- responses. mean response times for correct trials only and standard deviations (in parenthesis) were as follows: symmetry judgment ‘‘yes’’ ms ( ms), . % errors; symmetry judgment ‘‘no’’ ms ( ms), . % errors; aesthetic judgment ‘‘yes’’ ms ( ms); and aesthetic judgment ‘‘no’’ ms ( ms). a repeated-measures analysis of variance (anova) over the judg- ment latencies with the factors judgment task (symmetry/ aesthetic) and answer (yes/no) revealed an interaction ( f( , ) = . , mse = . , p = . ). no other effect was significant (task, f( , ) = . , mse = , . , p = . ; and answer, f( , ) = . , mse = , . , p = . ). further investigation of the interaction task by answer showed an effect for the judgment latencies for answer under the aesthetic task, with beautiful patterns being slower to be answered ( f( , ) = . , mse = , . , p = . ). summarized judgment latencies for the tasks symmetry and aesthetics were significantly slower than those for the baseline trials ( f( , ) = . , mse = , . , p < . ). an anova over the symmetry judgment errors revealed no signifi- cant effect ( f < ). summarized judgments errors for the symmetry task were significantly higher than those for the baseline trials ( f( , ) = . , mse = . , p = . ). . % of the stimuli under the aesthetic judgment task were judged as beautiful, . % as not beautiful, the difference being statistically significant ( f( , ) = . , mse = . , p = . ). imaging results aesthetic and symmetry judgments versus control condition in both judgment tasks, assessed separately versus the control condition cc (aj–cc, sj–cc), activity was observed in the dorsal frontomedian cortex with a maximum probably within mesial ba , the intraparietal sulcus, the inferior precentral gyrus (ventral premotor cortex), the anterior inferior frontal sulcus, fusiform gyrus, pulvinar nucleus of the thalamus (dorsomedial nucleus), superior anterior insula, ventral tegmental area, and extrastriate visual cortex. while frontomedian activation extended more anteriorly for aesthetic judgments (aj–cc) than for symmetry judgments (sj–cc), symmetry judgments but not aesthetic judgments caused activation in the bilateral dorsal premotor cortex at the crossing between superior precentral sulcus and superior frontal sulcus. aesthetic judgments versus symmetry judgments the direct contrast revealed that a number of areas were differentially activated by the two categories of judgment tasks under investigation (fig. , table ). aesthetic judgments (aj–sj) elicited activation within the right frontomedian cortex (ba and ), extending bilaterally onto the convexity of superior frontal gyri, and in adjacent areas of the anterior cingulate cortex (ba ). other foci were observed within the posterior cingulate cortex, the inferior precuneus, the right and left inferior frontal gyrus (ba / ) extending into the lateral orbitofrontal cortex in the left hemisphere, the left temporal pole, and the temporoparietal junction. in contrast, symmetry judgments (sj–aj) caused bilateral activation within dorsal premotor cortex and the superior parietal lobule, the intraparietal sulcus, left ventral premotor cortex, left fusiform gyrus probably corresponding to the so-called fusiform face area (ffa; kanwisher et al., ), and the visual cortex. beautiful versus not-beautiful judgments, and symmetric versus not-symmetric judgments in order to identify valence effects within the networks specifically engaged for either aesthetic or symmetry judgments, bold signal changes were extracted from voxels with maximal activation in areas identified by direct task contrasts aj–sj and sj–aj. considering firstly areas with higher activation for aesthetic as compared to symmetry judgment (aj–sj), some of them showed a higher signal for beautiful as compared to not- beautiful judgments (dorsal frontomedian cortex, ba / and temporal pole), whereas all others were indifferent. selected t tests revealed, however, that the signal difference beautiful versus not-beautiful reached significance only in ba (x/y/z = / / ; p = . ), which is in accordance to this areas’ connectivity with ba / and temporal pole (ramnani and owen, ). all of these areas were indifferent with respect to the two symmetry judgments. considering areas with higher activation for symmetry as compared to aesthetic judgment (sj–aj), no differences were found for signal changes of either symmetric or not-symmetric judgments. interestingly, however, judged-as- beautiful pictures showed a higher signal than judged-as-not- beautiful pictures in the left intraparietal sulcus (x/y/z = � / � / ), though with a t test reaching only marginal significance ( p = . ). overall, hence, symmetry had no significant influence on signal changes, whereas beautiful judgments led to higher signal changes than not-beautiful judgments in frontome- dian ba , i.e., an area which was specifically engaged in aesthetic judgments, as well as in the left intraparietal sulcus, i.e., an area which was specifically engaged in symmetry judgments (fig. ). since each stimulus was presented only once to a participant over the course of the experiment, the assessment of mere valence effects was restricted by this fact. contrasting beautiful fig. . brain correlates of experimental tasks. group-averaged (n = ) statistical maps of significantly activated areas for aesthetic judgments as opposed to symmetry judgments (left panel) and for symmetry as opposed to aesthetic judgments (right panel). z-maps were thresholded at z = . ( p < . corrected). bar charts depict maximal signal changes (% sc) for the two areas in which beautiful judgments (b) caused a higher bold signal than not-beautiful (nb) judgments (afmc = frontomedian cortex at ba , and left ips = intraparietal sulcus). in contrast, no significant differences were found between symmetric (s) and not-symmetric (ns) judgments. further abbreviations: ifg ( / ) inferior frontal gyrus at ba / . t. jacobsen et al. / neuroimage ( ) – versus not-beautiful judgments (under this restriction), we found the left junction of the inferior frontal sulcus and inferior precentral sulcus (x/y/z = � / / ) and extrastriate visual areas (x/y/z = /� / and /� / ) to be more engaged when subjects judged a stimulus to be beautiful (no activation was found for the reverse contrast). activation in these areas may owe to the particularly extended visual analysis preceding the beautiful judgment ( ms versus ms) and thereby the shortly postponed assignment of the key to the currently evaluated stimulus. note, however, that viewing time was the same for all conditions, as stimulus presentation was not response-dependently aborted (cf. analysis in vartanian and goel, ). parametric effects of complexity finally, a parametric contrast was calculated to test for the correlates of stimulus complexity. complexity was measured by the number of separate elements in a stimulus pattern (see materials and methods section). the complexity value was . elements on average (t . sd) and ranged from to . these values entered the parametric analysis testing for the effect of stimulus complexity separately for aesthetic and symmetry judg- ments. for both judgment conditions, increasing complexity caused significant activation within the fusiform gyri (aesthetic judgment: x/y/z = � /� /� , � /� /� , /� /� , and /� /� ; symmetry judgment: � /� /� , � /� /� , /� / , and /� / ). this effect was descriptively dominant for symmetry judgments. condition-specific effects of complexity were observed in the right lateral fronto-orbital cortex for aesthetic judgments (x/y/z = / /� ), and within the right anterior inferior frontal gyrus (x/y/z = / / ) and the right ventral premotor cortex (x/y/z = / / ) for symmetry judgments (fig. ). discussion the present fmri study aimed at identifying the neural correlates of genuine aesthetic judgments of beauty. novel, abstract graphic patterns were employed to minimize influences of attitudes or memory-related processes. as aesthetic judgments are known to be often guided by criteria of symmetry, evaluative aesthetic table anatomical area, hemisphere (r right, l left), talairach coordinates (x, y, z), and maximal z scores (z) of significant activations of the direct contrasts anatomical area hemisphere x y z z aesthetic judgment versus symmetry judgment frontomedian/anterior cingulate cortex (ba / ) r . frontomedian cortex (ba ) r . superior frontal gyrus (ba ) r . posterior cingulate cortex r � . inferior precuneus l � � . inferior frontal gyrus (ba / ) l � . r . temporal pole l � � . temporoparietal junction r � . l � � . symmetry judgment versus aesthetic judgment superior parietal lobule l � � . r � . intraparietal sulcus l � � . precentral gyrus (dorsal premotor cortex) l � . r . precentral gyrus (ventral premotor cortex) l � . fusiform gyrus (face area, ffa) l � � . extrastriate visual cortex l � � . t. jacobsen et al. / neuroimage ( ) – judgments were moreover compared with descriptive symmetry judgments on the same stimulus material. results revealed both types of judgment to rely on a set of areas supporting high-level visual analysis. as hypothesized, however, direct contrasts showed specific activations for aesthetic judgments; these were located in the medial wall (ba / and inferior precuneus) and bilateral ventral prefrontal cortex (ba / ), i.e., regions which have been previously reported for social or moral evaluative judgments on persons and actions (cunningham et al., ; greene et al., ; johnson et al., ; moll et al., ; zysset et al., ). aesthetic judgments also engaged the left temporal pole and the temporoparietal junction. in contrast, symmetry judgments elicited specific activations in several areas related to visuospatial analysis, including superior parietal lobule and intraparietal sulcus as well as dorsal premotor cortex (wager and smith, ; schubotz and von cramon, ). interestingly, when participants judged a pattern to be beautiful (as in contrast to not beautiful), not only areas dominant in aesthetic judgments, but also one area specifically engaged in symmetry judgments (left intraparietal sulcus) showed fig. . brain correlates of parametric effects of stimulus complexity in aestheti conditions, activation was enhanced by high complexity in fusiform gyri. diffe judgments, and in the right prefrontal and premotor area for symmetry judgment an enhanced bold signal. moreover, the parametrically manip- ulated and a second important factor of aesthetic judgment, stimulus complexity, caused differential effects for each of the two judgments types, including right lateral fronto-orbital cortex (ba / ) for high complexity during aesthetic judgments. against the background of the literature, present findings indicate that aesthetic judgments of beauty recruit partially overlapping networks with social and moral judgments, but also specific areas which have not yet been reported for the latter. moreover, the behaviorally established significance of stimulus symmetry and complexity for our judgment of beauty was found to be reflected also by brain correlates. common activations of the aesthetic and the symmetry judg- ment reflected that participants encountered decisions under uncertainty, as indicated by activation of mesial ba , anterior insula, and ventral tegmental area (volz et al., , ). in contrast, direct comparisons revealed a cortical network for aesthetic judgments, parts of which are reported for social (cunningham et al., ; johnson et al., ), moral (moll et c judgments (left panel) and symmetry judgments (right panel). for both rential effects were observed in the right orbitofrontal cortex for aesthetic s. t. jacobsen et al. / neuroimage ( ) – al., ; greene et al., ), or other (zysset et al., ) evaluative judgments. one of these areas, frontomedian ba / , has attracted particular interest in recent years as almost no functional models exist for this area in the non-human primate. ba is a very large brain region in humans: in volumetric terms probably the largest single architectonic region of the frontal lobes (christoff et al., ). rostral prefrontal cortex (ba included) is in relative terms twice as large in the human brain as in many great apes (semendeferi et al., ). this region is possibly the last to achieve myelination, and it has been argued that tardily myelina- tion areas engage in complex functions highly related to the organism’s experience (fuster, ; burgess et al., ). in our aesthetic versus symmetry judgment, the center of activation was located within ba / , and ba activation was restricted to its polar subdivision (ba p; ongur et al., ). functionally, this region has been related to the explicit processing or introspective evaluation of internal mental states, i.e., one’s own thoughts and feelings (christoff and gabrieli, ). the notion of evaluation of internally generated information (as in contrast to externally available information) takes into account that the same area and networks were found in tasks related to mentalizing (happe, ) which requires self-reference as well (vogeley et al., ; gusnard et al., ; gallagher, ). our present findings are in accord with this account. thus, to give a candid answer in the aesthetic judgment task, subjects had to ask themselves ‘‘do i find this pattern beautiful?’’ in contrast, to judge upon symmetry all relevant information could be derived directly from the stimulus itself without explicit reference to one’s own thoughts or feelings. ramnani and owen ( ) in their review on area ba propose it more generally to be involved when integration of the outcomes of two or more separate cognitive operations is required in the pursuit of a higher behavioral goal. it is an open issue, however, whether the notion, as put forward by christoff and gabrieli ( ), that the lateral portion of ba supports relational integration, i.e., binding a large number of independent sources of variance, applies to the medial portion of area ba , too. it appears plausible, at least, that evaluative judgments necessitate complex relational integration in terms of multiple relations between external entities and mental states (kroger et al., ; christoff et al., ), or holding in mind goals while exploring and processing secondary goals (koechlin et al., ). mesial ba is known to be reciprocally connected with several areas which were also activated in aesthetic as compared to symmetry judgment, including the ventrolateral prefrontal cortex (ba / ), temporal pole, posterior cingulate cortex, and precuneus (barbas, ; pandya and yeterian, ; for a literature synopsis, see ramnani and owen, ). comparing our data with other findings on evaluative judgment so far, ba / in the ventral prefrontal area was found to be unilaterally activated in previous studies. zysset et al. ( ) reported left ba / for evaluative in contrast to either semantic or episodic judgments. cunningham et al. ( ) found right ba / for good–bad in contrast to factual judgments made on famous people, and signal in this area was found to particularly increase for ambivalent judgments. authors take this effect to support that evaluative judgments reflect a constructed online process rather than a controlled activation of a memory representation. in accordance with this view, and because probably most of the stimuli were not judged to be absolutely beautiful or absolutely not beautiful, bilateral ba / activation in our study may reflect a particular demand of the aesthetic judgments, namely to map a non-dichotomous judgment onto a binary decision (for involve- ment of both hemispheres in aesthetic judgment, see also regard and landis, ). indirect evidence for this interpretation comes from the finding that the bold signal of a directly adjacent orbitofrontal area was found to positively co-vary with stimulus complexity during aesthetic judgments only. furthermore, work by cunningham et al. ( ) suggests that the stronger recruitment of areas ba / , ba / , anterior cingulate, and the left temporal pole in the present evaluative judgment task depended on the intentional nature of the processes (as in contrast to implicit processes of evaluation). with regard to aesthetic judgments, complexity was found to account for the second-most amount of variance at the group level, as outlined in the judgment analysis. overall, pictures that contained more elements were considered more beautiful. the parametric effect in this area may hence reflect the particular conflict arising when subjects evaluated a complex stimulus, and often against the principal bias for not-beautiful judgments. a further area specifically co-activated with ba in aesthetic judgment, the temporal pole, has been suggested to be concerned with generating, on the basis of past experience, a wider semantic and emotional context for the material currently being processed (frith and frith, ). finally, the potential contribution of posterior cingulate cortex and precuneus to aesthetic judgment may relate to their role in memory retrieval (fletcher et al., ; shallice et al., ; buckner et al., ; dobbins et al., ; nakamura and kubota, ), particularly successful episodic memory retrieval (cabeza and nyberg, ). as outlined in the introduction, we aimed to minimize or even rule out memory- related confounds by using a non-referential, abstract stimulus material. what may be the particular role of memory retrieval in aesthetic judgment as compared to symmetry judgment? one possibility is that participants, in order to give an appropriate answer according to their subjective valence system, engaged in a spontaneous comparison of the graphic patterns with patterns they were already familiar with. this could be done in two ways. firstly, participants could have spontaneously associate the graphic stimuli they were presented with to the similar patterns they were already familiar with before the experimental session, as e.g., grandma’s bobbin lace. secondly, participants could try to retrieve their own judgments on prior patterns in the experiment, or run a comparison to facilitate their judgment, saying e.g., that the present pattern is more or less beautiful than the preceding one. in this context, it is particularly interesting that the precuneus responds to the repeated exposure to stimuli (maguire et al., ; dolan et al., ). together with posterior cingulate cortex, this region is hence suggested for fitting new information into an established mental framework of prior knowledge (maguire et al., ). in either way, present effects in memory-related networks signify a strong behavioral bias to use episodic or semantic memories to guide aesthetic judgment. the valence of aesthetic judgments had a significant influence on the bold signal in several of these areas and, interestingly, also on the left intraparietal sulcus involved in symmetry judgments. on the one hand, signal boost in areas related to aesthetic judgment may reflect the particularly intensive evaluation before assigning a stimulus to the category of beautiful items. this view is substantiated by the general and statistically significant tendency of the participants to find patterns not beautiful ( . % ‘‘beautiful’’ as compared to . % ‘‘not beautiful’’) and to need significantly t. jacobsen et al. / neuroimage ( ) – more time for beautiful ( ms) than for not-beautiful judgments ( ms). on the other hand, beautiful judgments caused higher signal changes than not-beautiful judgments in left intraparietal sulcus engaged in symmetry judgments. one might argue that this effect cannot be unambiguously attributed to the (subjective) beauty of the stimulus, since symmetric items were more frequently judged to be beautiful ( . %, sd . ). however, symmetric judgments did not cause higher signals than not-symmetric ones in this very area. it can therefore be ruled out that the ‘‘beauty-induced’’ signal boost in left intraparietal sulcus was due to (the perception of) a higher ratio of symmetric patterns among those judged as beautiful. this effect may rather reflect, in our view, that the analysis of stimulus symmetry was boosted whenever participants found a stimulus beautiful. metabolic findings hence nicely parallel the behavioral finding that, in many participants, symmetry guides aesthetic judgments of beauty. conclusion the present study shows, for the first time, that aesthetic judgments of beauty trigger activation in a brain network that generally underlies evaluative judgments, and hence share neural substrate with, e.g., social and moral judgments. since judgments of beauty often base on the analysis of stimulus symmetry, a descriptive symmetry judgment was employed for comparison. the differential patterns of metabolism demonstrate that brain activations during aesthetic judgment cannot be reduced to an assessment of symmetry but are actually due to a particular mode of judgment. acknowledgments this work was partly supported by dfg grant ja / - . the authors are grateful to three anonymous reviewers for helpful comments on an earlier version of the manuscript. references aharon, i., etcoff, n., ariely, d., chabris, c.f., o’connor, e., breiter, h.c., . beautiful faces have variable reward value: fmri and behavioral evidence. neuron , – . barbas, h., . architecture and cortical connections of the prefrontal cortex in the rhesus monkey. adv. neurol. , – . berlyne, d.e., . novelty, complexity and hedonic value. percept. psychophys. , – . brehmer, b., joyce, r.b., . human judgment: the sjt view. north- holland, amsterdam. buckner, r.l., raichle, m.e., miezin, f.m., petersen, s.e., . func- tional anatomic studies of memory retrieval for auditory words and visual pictures. j. neurosci. , – . burgess, p.w., simons, j.s., dumontheil, i., gilbert, s.j., . the gateway hypothesis of rostral prefrontal cortex (area ) function. in: duncan, j., mcleod, p., phillips, l. 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( ) explain the origin of the “height premium”, i.e., the increase in wage that goes with an additional inch of height, and find that it is the height at teens age that essentially determines the returns to height. recent research has studied how physical appearance, i.e., beauty, affects labor markets outcomes. however, this task is usually complicated by the fact that different groups may have different productivities. hamermesh and biddle (h&b, ) and biddle and hamermesh ( ) found evidence that beauty affects earnings irrespective of gender. they also found that the labor market sorts the best-looking people into occupations where looks are likely to be more important (hence productive), but this latter evidence is rather weak. using physical appearance as a possible source of discrimination makes it easier to distinguish labor-market outcomes arising from discrimination against a group (the homely in this case) from those produced by unobserved productivity. in fact, it can be argued that there are activities in which appearance is more important and where the payoff to beauty then reflects productivity, and other jobs where any such payoff reflects pure discrimination. similarly, for the uk labor market, harper ( ) found that physical appearance has a substantial effect on earnings. he also found that beauty has a very significant impact in the marriage market. however all these studies, like many others on the effects of various ascriptive characteristics on wages, find it difficult to distinguish whether the wage differential is due to becker-type discrimination stemming from tastes or to differences in productivity. indeed, “.. it is very difficult to construct a research design that allows one to distinguish labor-market outcomes arising from discrimination against a group from those produced by intergroup differences in unobserved (by the researcher) productivity..” (h&b, : ). in an attempt to disentangle these effects, a recent paper by pfann et al. ( ) on a sample of dutch advertising firms finds that those with better-looking executives have higher revenues and hence pay them more. however, the fact that beauty is highly productive in the advertising sector may not come as a surprise. another paper by hamermesh and parker (h&p, ) shows that lecturers who are viewed as better looking receive higher instructional ratings by their students. then, ceteris paribus, these higher ratings translate into higher salaries, because us university administrators pay attention also to teaching quality in setting salaries. however, the question remains on whether students are simply discriminating against ugly professors by reacting to an irrelevant characteristic, or if they do really learn less from them. and again, more generally, “... disentangling the effects of differential outcomes resulting from productivity differences and those resulting from discrimination is extremely difficult in all cases …” (h&p, : ). this paper is a contribution to the debate on whether the labor market outcome of ascriptive characteristics represents productivity or discrimination. using a rich set of data from the college of economics at the university of xx, we examine the effects of students’ physical appearance on examination results. we find evidence that beauty has a significant impact on academic performance, a result which is consistent with and comparable to the impact found in the labor market literature. in addition, since we can compare student performances in oral and written exams, where in the latter the evaluation is blind, i.e., not influenced by physical appearance, we can in fact understand better the source of the “beauty premium”, that is disentangle productivity from discrimination effects. we find that the effect of beauty on academic performance cannot be ascribed to pure professor discrimination. one could then argue that to the extent that wages rise with educational attainments, our findings corroborate the hypothesis that the payoffs to beauty reflect differences in productivity. the paper is organized as follows. section ii describes the working of university system for students in italy and the dataset that we use to analyze the role of looks. section iii presents the main empirical results of the paper, first showing the impact of beauty on students’ performance and then disentangling the discrimination and productivity effects. section iv briefly discusses some possible explanations based on psychological and economic theories which help to interpret our results. section v concludes the paper. ii. data and institutional details in the - academic year, a substantial reform of university degrees took place in italy. in order to make university education more suitable for the job market and to improve on graduation rates, the official duration of undergraduate degrees was reduced from to years. according to the ministry of university, this would make the italian university degrees (laurea) more comparable with analogous degrees in other european countries, as agreed with the bologna convention among eu education ministers. in addition, in the new system more motivated students can further acquire education by adding more years to obtain a specialized degree, the laurea specialistica, and then enter into phd programs. students enrolled at the college of economics at the university of xx, like those in most italian universities, are offered two types of examinations, verbal or written. each professor is free to choose whether to set an oral or a written exam. in some cases the exam is both oral and written, but only a final mark (sometimes the average, some other times other combinations) is recorded. in addition, in italian universities students are allowed to take examinations many times during the academic year, and it may happen that a student attending a class can take the exam either at the end of the course or in other dates during the following months or even years. therefore there is more than one examination session in the academic year and in each session a student can take (almost) as many exams as he/she likes. in the period under consideration, in the college of economics there were sessions every year. the winter session, held in january and february, was about week long, and the exams for each course were delivered at three different dates, at least two-week apart; the summer session, in june and july, about - week long, in which again for each course students had the opportunity to take exams three times; and the fall session, shorter ( weeks), in which exams were delivered only one or at most two times per course. therefore, every year students had the opportunity to find to dates at which to take the exams for each course. the exam evaluation and grading is based on grades with a scale going from to (with cum laude being awarded in some cases) and the pass threshold set at . however no mark is ever recorded when below . if students fail an exam, i.e., they get a grade below , there is no official record of the event (nor even that they have attempted), and they can take the exam again some other time. when marks are released, but before they in italian universities, on average, the drop out rate under the old system was %. the average time spent to complete a first degree was years and only . % of students graduated on time. with the new system of three-year degrees provisional results show that % of students graduate on time, that is within . years (istat, ). are recorded, students can refuse to register the mark in order to re-take the exam in the future and perhaps get a higher mark. in this case, again, there is no record of the first attempt. finally, there is no upper limit on the number of years students can take to finish their degree. in order to graduate, however, a student has to pass a certain number of exams. moreover, the final grade coming with the awarded degree is calculated on the basis of the simple average of grades obtained during the academic career. table presents the statistics describing our variables. we have collected data on the cohort of students at the college of economics at the university of xx registered for their first time in the academic year - , observed over three years. there are students in the dataset, . % of which are female. in our dataset we have data on the type of high school they attended, on the high school final grades, the date of birth, and the home address. we also obtained detailed information about each student’s academic curriculum with examination dates and marks. our dataset records all individual grades up to the summer session. in theory, since the official duration of their course was years, by that session any student in our cohort could have graduated. however, a negligible number of students - only - did actually graduate. some students will have graduated over the following months, and many more will graduate in and later years, when they complete all the required exams. quite a lot of them, however, will never graduate. [insert table about here] for each student, photo-id pictures were also available. each of the student’s pictures was rated by each of five professors: women and men aged respectively , , , , (to accord with the age and sex distribution of university professors in the college). the raters viewed all photographs on a high resolution computer screen, one by one, and could tick beauty on a (highest) to rating scale. of course, the ideal measure of beauty would account for all of a person’s features capable of making a visual impact on the observer and not just the facial features. however, the error this may introduce in the beauty measure is unlikely to be systematically related to any of the variables we focus on. also, jackson ( ) has shown that there is a high correlation between responses to still photographs and responses to video tapes of the same stimulus person. finally, the cited literature on the economics of beauty has always used still photographs. in the years under consideration, the required number of courses and hence exams was . they were instructed to use for average look, and for respectively better and worse than average, and for respectively the beautiful or handsome and the homely. they were allowed to move back to previously rated photographs to change or check their ratings. in a series of pair-wise correlations, we found correlations from . to . between panel members, always highly significant, and given the number of pictures this seems to suggest a substantial agreement among evaluators about the appearance of individuals, thus confirming the existence of common standards of beauty, as found in the rest of the literature. for the beauty index we will use, however, we standardized each rater’s evaluation and then created a composite standardized beauty measure for each student by summing the five standardized ratings. iii. looks and the exams the tuition fees for public universities in italy are rather low, and thus it is quite common that many students are enrolled at university without actually taking exams. in our cohort about % of the students have not passed a single exam. these may be students who have never taken an exam, for example because they enrolled just out of high school while looking for a job and then found one, or they may be students who have never passed an exam despite attempting. although, as already explained, we do not have official university records of students’ failed attempts, evidence collected from colleagues teaching first year courses suggest that about % to % of students fail each time. this seems to suggest that a large portion of “non participating”, i.e., not taking exams, students are actually participating but do fail. an important aspect of this study is to investigate the effect, if any, of the physical appearance on the performance of students. hence, we consider the impact of beauty on an indicator of performance that takes into account both the number and the grades of the passed exams using a series of regressions that we present in the next section. in addition, in the sections that follow, we further investigate this issue by looking at the effects on the number of exams and on the average grade obtained separately, plus some other variables that allow us to distinguish between the impact of beauty due to discrimination and productivity. preliminary to our analysis we run a probit regression on the participation of students, i.e., having or not passed any exam. the result show that whether or not exams are taken is dependent upon beauty. therefore, using ols on the number of exams taken only for those students for whom this number is positive gives downwards biased results. about euro per year at the university under consideration, with similar levels for other italian public universities as well. also, the number of exams, as well as our index of performace described in the next section, are censored variables where observations are clustered at a lower threshold (zero or eighteen) since no mark is ever recorded below the pass mark. since in principle marks could take on values below eighteen but we do not observe them because of censoring, we employ tobit estimates using all students in the sample. iii. evidence of the “beauty premium” as a primary index of performance we use a composite index of the number of exams times the average grade, which is equivalent to the cumulative sum of the grades of the exams passed by the student (checchi and pravettoni, ): , n n i i i i ij ij j ji perf n g n g g n ? ? Ã Ô ? © ? © © ?Ä Õ Å Ö Â Â where ni is the number of exams passed by student i, ig is the average grade, and gij is the grade obtained in the j-th exam. notice that italian students need to pass successfully a given number of exams before being awarded their laurea. the final grade however is proportional to the grades obtained in all the exams during the academic career and hence a student trying to finish her studies in a shorter time may be able to do it at the expense of a lower average and hence final grade. since we are considering the records of each student taken at the end of their third year, our composite index takes into account both the ability to be fast, i.e., to do a greater number of exams and hence to finish earlier, and to have good grades. at this stage we are interested on whether physical appearance has an impact on performance and hence we estimate the following: log , i i i i perf x bd i g? - - where xi is a vector of student i’s characteristics and bi is the student’s index of physical attractiveness. as explained before, since all performances below (one exam times the lowest recorded mark of ) are not registered, we need to employ tobit estimation of students’ performance on their set of characteristics to take truncation into account. according to our results (table ), better looking students perform better in the exams: the coefficient is positive and highly significant (at %). moving from one standard estimates are available from the authors upon request. deviation below the mean to one standard deviation above leads to an increase in the performance of about %. hence there appears to be evidence that beauty – as already found in labor markets, where it affects wages – can affect performance. in addition, the magnitude seems comparable to what is found in labor market studies. for instance, h&b ( ), using data from north-america, found pay premium for above average looking people of about - % and pay penalties for below average looking people of - %, according to the available dataset. harper ( ), using uk data, found a pay penalty ranging from % to . % for unattractive men and around . % for unattractive women. [insert table about here] before testing for the robustness of this result, however, we look also at the effect of other characteristics on students’ performances. being just out of high school (year_ ), on the other hand, increases the probability of doing better at university. this effect may be related to the fact that these students are in a sense just “minted” (fresh of studies) and hence may find it easier to pass exams. alternatively, and more likely, these students in fact do not participate yet in the labor market, and hence their opportunity cost of studying may be lower than part-time students, i.e., those that have already a job. in other words, these students may have acquired and not yet forgotten the right skills to succeed in school, or more likely, fresh graduates may have fewer occupation opportunities and hence may happen to be full-time students and be less distracted by work duties from their academic career. a similar effect is related to the type of high school the students were enrolled before going to university. it appears that students who attended a “liceo”, i.e., a high school that gives a general purpose education, either in the humanities, sciences, liberal arts, or languages, are better performers than student coming from professional schools. indeed, professional schools are known for being less demanding on their students while the curriculum is more rigorous and demanding in a liceo. technical schools are more demanding than a professional school and less than liceo, however the corresponding dummy variable is not significantly different from zero. the students coming from liceo have probably fewer opportunities in the labor market in the short run, at least compared to students graduated from technical or professional high schools, and hence their opportunity cost of studying may be implicitly lower. although we would need to have more information, for instance on family background, to explain in the north-east of italy, the unemployment rate is quite low (about . %), even among young people ( . % for - and only . % for - year old). educational choices and students’ performances, notice that the type of high school chosen is in fact related to family background, especially income levels and parents occupation and class, e.g., working or middle class. middle class families, indeed, tend to send their children to liceo, known for being better equipped to prepare students for universities, where they expect their children will go after high school. on the other hand, working class families may prefer technical schools, known for providing an education better suited for the job market after school. in other words, the choice of the type of schools may reflect, to some extent, the family economic and educational background. given the same family background, moreover, the choice of the type of school may reflect sorting of students based on their educational abilities: other things equal, students going to professional schools may be expected to be less performing on educational matters. for this reason, the choice of the type of school attended may also partially pick up students’ ability. a better proxy for student ability, however, is the final grade, i.e., the graduation grade, from high school. as one would expect, its impact is positive and highly significant on students’ performances. to the extent that this grade reflects students’ abilities, one can conclude that the more able students coming out of high school also perform better at university. another variable that significantly affects students’ performance is the final grade obtained in the state exams at the end of high school. this variable is very likely related to students’ ability and it is not surprising to find a significant effect, which is also the biggest in magnitude among the variables used in these regressions. we also considered a dummy variable (eci) for those students enrolled within the same college but in a degree program managed in a nearby city. this degree program differs in terms of facilities (there are less) and, in part, teaching faculty (more junior, part-time or temporary). the dummy is always significant and positive in this and all the subsequent estimates, meaning either that students enrolled in this program have better abilities or, more likely, that exams there may be relatively easier to pass. the dummy for gender is not significant. however, when estimating separate regressions for males and females, we find a positive and significant effect of beauty only for males, confirming what is found in the labor markets literature. looking at other regressor, characteristic that has an impact on performance but only for males and at the % level, is the fact that the student is resident in the area where the course is offered (resident). if we believe that a student who decides to enroll into a course offered in her own town (province in our case) may be less motivated than a student who decides to enroll into a course in another city, we have to expect that the resident student may have lower performances. as can be seen from table , the coefficient is indeed negative. it is interesting to investigate on whether there is a premium for being handsome or a penalty for being homely and if these two effects are in fact symmetrical. in the literature indeed there have been different findings. h&b ( ), analyzing us data and estimating human capital-type earnings equations, found that penalty for unattractive people were greater than premiums for attractive people. the same authors, using canadian data, however found that premium were larger than penalties, with these latter being insignificant. harper ( ), using data from the uk job market, found a larger penalty for unattractiveness than h&b ( ). we construct a dummy (handsome) for the top % most beautiful students and another (homely) for the bottom % least beautiful students and estimate separate regressions for males and females. as it appears from the last two columns of table , there is a significant penalty for being homely for male students since being in the bottom % reduces our index of performance to % below the average. on the other hand, the premium is small and insignificant for males and only significant at % for female students. in summary, we have shown that physical appearance has a significant and economically meaningful effect on the performance of students. first of all, being handsome increases the probability that a student in fact takes and pass exams. second, and more important for us, better looking students have better performances than other students. last, we find that the premium for beauty is smaller than the penalty for ugliness. while less economically important than the effects of the proxies for education and ability, these impacts seem quite significant, as already observed in the literature on labor market outcomes. we now turn to investigating on whether the increase in performance is related to different students’ productivity or to discrimination. iii. it’s not discrimination, is it? in this section we wish to determine whether the effect of beauty on student’s performance is the result of unobserved productivity or of pure discrimination by professors. if we can reject pure discrimination, one can safely assume that the effects of beauty on performance may be explained by different students’ productivity. to investigate the presence of pure discrimination effects we proceed in different steps. first, as a preliminary check, we look at the effects of beauty separately on the average grade and on the number of exams passed. while the discrimination effect of beauty may be at work in obtaining higher grades – teachers could be influenced by physical appearance when they can actually see it – it is less clear how it would influence the number of exams passed. the number of exams taken and passed is more the result of students’ choices and effort, and so could perhaps reflect more productivity than discrimination. second, we exploit the type of examination – either oral or written – to disentangle the effect of beauty. given that in written examinations physical appearance is unnoticed, our dataset should allow us to see if there is some support to the hypothesis of pure discrimination. if look had a (positive) impact on oral exams grades but were unimportant in written exams, then we could start asking whether these different effects where due to discrimination or whether the type of examination, in the case of the oral exam, was such to disadvantage homely people who may just be less confident and under perform in an oral exam. an important variable in our dataset is thus the number of exams that each student has taken in the period under consideration (almost years). as explained in the previous section ii, this is partly a choice variable, partly the result of students’ effort and ability, in the sense that students graduate when they have passed a given number of exams, but there is no lower limit on the number of exams that must be taken each year and a student is allowed to stay enrolled for as many years as he chooses to. again, since students may in fact have taken exams but not passed them, we need to use tobit analysis. we then estimate the following equation: , i i i i n x bd i g? - - and table reports the results of the tobit estimations of the number of exams passed (ni) on different students characteristics. physical appearance is significant, like other variables such as the dummies for the type of high school completed, being just out of high school, and not being resident at the university’s location, confirming again the results found for the composite performance index. the dummy for being a male student is not significant in explaining students’ performances in terms of number of exams. however, performing separate regression for each gender, we find that physical appearance is significant only for male students. moving from one standard deviation below the mean to one standard deviation above increases the number of exams passed by about % with respect to the mean. this result confirms the impact of beauty on the composite index of performance already seen before, both in significance and in the order of magnitude. the number of exams passed in the interval considered is a clear measure of productivity and thus we believe this is a first signal that beauty has a productivity effect. the other variable related to performance that we employ is the exams average grade and thus we estimate the following: , i i i i g x bd i g? - - where i g is the average grade, obtained in the exams. this measure of performance is censored too. indeed, the grades are on a scale between and , but in order to pass an exam the minimum grade is , and it is a general practice that only the grades equal or above are registered, while in case of failing the exams, i.e., grades below , these are censored. to control for this we use a tobit regression model. as before, beauty does not seem to have any significant effect for females, while it is significantly different from zero for males even though its impact is not high. the dummies for the type of high school attended before enrolling at university plus the final high school grade are also significant. following the second path in our investigation, we look at the, possibly differential, impact of beauty on written and oral examinations. in the years under consideration, exams were to be passed in order to graduate and obtain the laurea. however, the average number of exams passed by active students, i.e., those who took at least one exam, was just below , and only ten students actually finished all the exams and graduated. thus, even though the type of exam for each course – either written or oral – is a choice of the professor, which exams to take first is decided by the student. in table we report the results of tobit regressions on the number of written and oral exams respectively. the impact of beauty for males appears to be positive for both type of exams, but more important for written examinations where an identical increase in beauty increase almost twice as much the number of exams. if we believe in a pure discrimination effect of beauty, we would expect, if any, that handsome students would take more oral exams, where their beauty could be appreciated. since we find the opposite result, i.e., that beauty has more of an impact on the number of written exams, we believe this gives more support to the productivity hypothesis and less to the pure discrimination hypothesis. looking at the average grades for written and oral exams, in table , we find that the beauty coefficient is significant for both oral and written exams average grades. again the effect is stronger on written exams. we believe that if beauty had a pure discrimination effect, we should find a greater impact of beauty on the oral exams average grades, which we do not. again, the (lack of) evidence in this last set of regressions appears to be more consistent with a productivity effect of beauty. we also investigate whether beauty has any impact on students’ differences in performances between oral and written exams by estimating the following: , i i i i perf x bd i gf ? - - where fperfi is the difference in performance between oral and written exams. the performances in this case are measured in terms of average grades and number of exams, as we will describe shortly. in general, if we believe in the pure discrimination effect of beauty, we should expect a better performance of good looking students in oral exams, especially in terms of average grades. in other words, if students show better performances in oral exams and beauty is found to have a positive and significant impact on it, i.e., ,i @ there would be some evidence of discrimination. in table we report the results of an ols regression on the differences between the average grades obtained in oral and written exams on the usual explanatory variables. beauty’s coefficient is not significantly different from zero, as almost all other explanatory variables. in the same table, we also look at the impact of beauty on the difference between the number of oral and written exams passed by the students. to be consistent with a discrimination type of explanation for the effects of beauty on performances, we would expect i > , i.e., more handsome people doing more oral exams. instead, we find that when there is an effect of beauty, in the regression for males, this is in fact negative, meaning that better looking students have passed more written exams. again, if any, we believe that this evidence would be consistent with a productivity effect of beauty. to summarize, we believe that we have evidence that allows us to reject the pure discrimination effect of beauty on performance. instead, given that in our dataset beauty does in fact affect students’ performances at university, we argue that we can opt for a productivity type of explanation: more handsome students are also more productive. we explore possible explanations for this result in the following section. incidentally, this result seems to provide support to the theory that society has higher expectations on the performance of beautiful people compared to the rest. given these expectations, an average performance by iv. discussion: why is better looking also smarter? this research has found a relationship between attractiveness and an index of performance. the motivation of our study was the economic literature on beauty and the labour market and its startling result that looks have a clear impact on earnings. an important unanswered question in the literature is asked directly by daniel s. hamermesh when he describes his research on the economics of beauty: “do good looks make people more productive – can we ever distinguish between the effects of beauty, or some other characteristic, as discrimination or productivity?”. by distinguishing between oral exams (where beauty is observed) and written exams (where it is not), this paper has not found any direct evidence for discrimination, a result similar to experimental economics evidence that ruled out any becker-type discrimination effect (mobius and rosenblat, ). thus our evidence suggests that good looks could make people more productive. in this section we will discuss some of the existing literature on the effects of facial attractiveness in order to find a possible explanation for the positive relationship between beauty and productivity, starting with the non-economic literature. a very comprehensive review of the literature is that by langlois et al. ( ) which conducts a quantitative review of the effects of facial attractiveness using hundreds of papers from published and unpublished sources from to . this article concludes that: ) beauty is not in the eye of the beholder, i.e., contrary to conventional wisdom there is a common standard of beauty both within and across cultures. ) people do judge a book by its cover, i.e., attractive adults and children are judged more favourably and treated more positively than unattractive adults and children, even by those who know them. ) beauty is not only skin deep, i.e., although both attractive and less attractive individuals exhibit positive behaviours and traits, attractive individuals tend to exhibit more positive behaviours and traits than unattractive individuals. another important contribution of the aforementioned paper is to discuss the various theoretical mechanisms explaining why beauty influences judgment, treatment and behaviour. in this respect, the literature distinguishes between social expectancy theories and fitness-related evolutionary theories. the first set of theories is based on the assumptions that cultural norms and experience influence the behaviour of both targets and them is penalized. for a discussion of these effects in a public good experiment see andreoni and petrie ( ). perceivers and that social stereotypes create their own reality (like a self-fulfilling prophecy). the second set of theories posits that morphological characteristics are indicators of fitness, health, quality and reproductive value. according to this second group of theories, beauty is an important aspect in human relations which operates through channels like mate selection and differential parental solicitude. while the first channel makes no predictions regarding the importance of attractiveness for children, since they are clearly not involved in selecting a mate, the second channel could be designed to explain children’s behaviour. in fact, it posits that if attractiveness is perceived as an indicator of quality, adults should invest more in attractive than unattractive children to enhance their own reproductive success. based on their review of the literature, langlois et al. ( ) concludes that although predictions from both social expectancy and fitness-related evolutionary theories are partially supported, neither theory is totally successful in predicting the various findings, and much additional research is needed before we can find how and why facial attractiveness influences social behaviour and development. recent economic literature recognizes the growing consensus that physical attributes, e.g., beauty and height, can affect the acquisition of non-cognitive skills. these latter represent a form of human capital and contribute substantially to labor market success. heckman ( ), for instance, reports evidence that preschool programs improve students’ social skills and motivation and hence can raise lifetime earnings. persico et al. ( ) found that about half of the “height premium” in the labor market can be accounted for by variation in participation in school sponsored non academic activities. being tall as an adolescent, they conclude, facilitates the acquisition of some form of human capital, like social adaptability, confidence and the ability to interact socially with others. in a recent paper, mobius and rosenblat ( ) report the results of an experimental labor market study decomposing the beauty premium and identifying three channels through which physical attractiveness can raise an employer’s estimate of a worker’s ability. since the confidence channel influences workers’ beliefs, they show that better looking workers are substantially more self-confident. their paper is thus consistent with the psychological and economic research and the anecdotal evidence emphasizing that “... people do recognize the income-enhancing effects of confidence ...” and thus “... the need for positive-thinking and for self-esteem as one key to success ...” (mobius and rosenblat, : ). see his homepage at http://www.eco.utexas.edu/faculty/hamermesh/beautyblurb.htm in a theoretical paper, benabou and tirole ( ) analyze the value placed by bayesian rational agents on self-confidence and its effects in enhancing motivation. indeed, self- confidence is valuable to the extent that it improves the individual’s motivation to undertake projects and persevere in the pursuit of her goals. ability and effort may interact in determining performance: in most instances they are complements, and so a higher self- confidence improves the motivation to act. in addition, people have imperfect knowledge of their own skills and abilities, and standard observation shows that morale plays an important role in difficult endeavors. this recent theoretical literature thus accomplish to model the influence of behavioral traits, to be distinguished from cognitive ability, i.e., more productive skills that can be acquired through education or proper training, on earnings differentials. indeed, as bowles et al. ( ) emphasize, seemingly irrelevant characteristics such as height, beauty, obesity have a potential role as reliable predictors of earnings. to conclude and summarize, we view these theories as important in explaining our results. if beauty has an effect on performance, and one can rule out pure becker-type discrimination as we do, the hypothesis that good looks make people more productive finds some support in these theoretical mechanisms. essentially the higher productivity of attractive people could be the result of pure discrimination in the past because of different parental (and teacher) solicitude or of past and current social stereotypes that affect self- esteem and motivation and hence productivity via a self-fulfilling prophecy. we view the fact that we can rule out another important possibility, i.e., that differential attractiveness can simply influence professor appraisals of students’ performance though pure discrimination, as an important result of our paper. given this perspective, one can relate our results to complement the received literature on the effects of beauty in the labour market. if differential productivity at the university translates in differential productivity at work, differences in wages arising from differences in attractiveness could also be the result of different performances. in other words, the proportion of wage differential that can be attributed to greater productivity as opposed to discrimination may be higher than what is implied by the literature. v. conclusions as noted by langlois et al. the question of why and how stereotypes based on attractiveness originated in the first place remains unanswered. we conduct an empirical analysis using a large dataset of students’ records and find evidence of a positive impact of facial attractiveness on their performance at the university. this is in line with the results of a number of papers in the labor literature which find that workers’ looks have a positive impact on their earnings. the main results of our empirical analysis are three: ) the impact of beauty is positive and significant in the decision to participate, that is to sit and pass exams once enrolled at the university. ) beauty affects significantly and positively the performance of active students, i.e., students who chooses to sit exams. ) distinguishing between oral exams (where beauty can be observed by the professors) and written exams (where it cannot be observed) allows us to reject the hypothesis of pure becker-type discrimination based on beauty and stemming from professorial tastes. the paper concludes with a brief discussion of the theories advanced by the psychological and economic literature to explain why attractiveness may influence productivity. references andreoni, j. and r. petrie, . beauty, gender and stereotypes: evidence from laboratory experiments, mimeo, university of wisconsin. averett, s. and s. korenman, . the economic reality of the beauty myth, journal of human resources, , , - . becker, g., . the economics of discrimination, chicago university press, chicago. benabou, r and j. tirole, . self-confidence and personal motivation, quarterly journal of economics, , , - . biddle, j.e. and d.s. hamermesh, . beauty, productivity, and discrimination: lawyers’ looks and lucre, journal of labor economics, , , - . bowles, s., h. gintis and m. osborne, . the determinants of earnings: a behavioral approach, journal of economic literature, , - . checchi, d. and g. pravettoni, . self–esteem and educational attainment, working paper . , dipartimento di economia e politica aziendale, university of milano. hamermesh, d.s. and j.e. biddle, . beauty and the labor market, american economic review, , , - . hamermesh, d.s. and a.m. parker, . beauty in the classroom: professors’ pulchritude and putative pedagogical productivity, nber working paper series, # . harper, b., . beauty, stature and the labour market: a british cohort study, oxford bulletin of economics and statistics, , - . heckman, j.j., . policies to foster human capital, research in economics, , - . jackson, l.a., . physical appearance and gender. albany, ny: state university of new york press. langlois j.h., l. kalakanis, a.j. rubenstein, a. larson, m. hallam and m.smooth, . maxims or myths of beauty? a meta-analytic and theoretical review, psychological bulletin, , - . mobius m.m. and t.s. rosenblat, . why beauty matters, mimeo, wesleyan university, ct. persico n., a. postlewaite and d. silverman, . the effect of adolescent experience on labor market outcomes: the case of height, journal of political economy, , , - . pfann, g.a.; biddle, j.e.; hamermesh, d.s. and c.m. bosman. . business success and businesses’ beauty capital, economics letters, , - . shaw | the aesthetics of retrieval: beautiful data, glitch art and popular culture | anthropocenes – human, inhuman, posthuman login | register home news about about become a reviewer research integrity author guidelines editorial team articles issues submission contact start submission account login register research the aesthetics of retrieval: beautiful data, glitch art and popular culture author: debra benita shaw (university of east london) options share: a- a+ dyslexia view harvard citation style view vancouver citation style view apa citation style abstract at a time when the meaning of democracy is challenged by the power of algorithms and the politics of misinformation what has become apparent is that the valorisation of data is the defining characteristic of contemporary digital capitalism. in the marketing of ‘big data’ different forms of visualisation (dataviz) are employed to support the claim that a series of perfect signals can be abstracted from the background noise of the world’s incessant uploading of information. at the same time, ‘glitch’ artists and musicians have developed techniques which deliberately disrupt digital signals, randomly re-assorting ordered sequences to privilege noise over signal and aestheticize error. this paper will examine glitch as an artform which deconstructs the aesthetics of dataviz at the same time as it exposes what must remain hidden for it to retain value. it will propose a critical technique through which glitch artefacts in popular culture can be employed to explore the oppositional politics of posthuman subjects. keywords: blade runner , mr robot, max headroom, posthuman, aesthetics, glitch art, big data, algorithm how to cite: shaw d., ( ) “the aesthetics of retrieval: beautiful data, glitch art and popular culture”, anthropocenes – human, inhuman, posthuman ( ). p. . doi: https://doi.org/ . /ahip. views downloads published on oct peer reviewed license creative commons attribution . in rosi braidotti and maria hlavajova’s posthuman glossary ( ), david theo goldberg and jemma ng call for the inauguration of what they call ‘algorithmic studies … the critical study of the social, political and cultural life of the algorithm’ ( : – ). in this demand they are recognising not only the importance of algorithms to the operations of contemporary capitalism but that it is equally necessary to understand their part in the overall system through which culture is constructed and which is comprised of machines, people and their cultural artefacts. this system is cybernetic. it functions on the basis of read-outs from algorithmic processes which are fed back into the social through their cultural effects, a process which, in turn, produces new data on which the algorithms can feed. this constant process of feedback and feedforward incorporates market adjustments, currency values, commodity prices and information and transportation infrastructures at a global scale. at the same time, it effects ontological changes at the level of populations and individuals in such a way as to blur the boundaries between people and machines, social systems and information systems, data and knowledge. as a contribution to algorithmic studies, my proposal is to interrogate the politics of algorithms and how they provide for the conditions under which we experience the world with a particular emphasis on how algorithmic processes give rise to visual data. i want to explore the representation of massive data sets, bearing in mind what is compressed, elided or discarded, both in the refinement of data into information and the way in which it is produced as a visual experience. my aim is to contribute to a vocabulary through which the aesthetics of data visualisation (hereafter ‘dataviz’) can be critiqued and, at the same time, to examine the appropriation of digital ‘glitch’ art in contemporary popular culture. i will suggest that glitch effects in mainstream film and video offer a method of analysis which can engage with the way that the paradigmatic structures and sensibilities through which data is rendered ‘beautiful’ can be subverted. i see in this a potential for the glitch aesthetic to open these products to new forms of critique; to, in effect, expose the relationship between the form and content of screen media and the way that the process of subjectivation proceeds as an effect of digital capitalism. i am interested here in opening a way to the new dimensions of knowledge production that braidotti calls for and that she names the ‘critical posthumanities’ ( : – ) which, as she says ‘are both caught in and resisting the accelerating spin of neo-liberal logic of capitalizing on knowledge’ ( : ). in what follows, i will explore the graphics of big data commodification before drawing on the critical resources of glitch practitioners to examine glitch effects in denis villeneuve’s blade runner (villeneuve ) and sam esmail’s mr robot ( – ). beautiful data the term big data is used to describe both the messy flows of information that algorithms operate upon and the commodified results of that operation. it is the raw resource of cybernetic capitalism that, in the second decade of the twenty-first century, we all labour to produce and the by-product of our lives as organised through social media, the internet of things, financial transactions and cloud computing. at the same time, it is what constrains the form of our interactions, determines our access to resources and conditions the structures of our lifeworlds. for antionette rouvroy, the application of information processing to masses of data produces a kind of truth which is immanent and purely operational; which neither admits of, nor requires, any form of verification or testing. put simply, data speaks and the world responds accordingly. ‘it is no longer a matter of threatening you or inciting you’, states rouvroy, ‘but simply [of] sending you signals that provoke stimuli and therefore reflexes. there is no longer any subject in fact’ (rouvroy and stiegler : ). this is algorithmic governmentality which, as she says, has had fundamental consequences for ‘the … making of norms and how they breed obedience’ ( : ). in short, as hito steyerl puts it, ‘humans feed affect, thought, and sociality into algorithms, algorithms feed back into what used to be called subjectivity’ ( : ). in this scenario, the subject of modernity, the western european ‘self’ which is brought into being by the cogito and nurtured through modern science as the standard for patriarchal rationality is fatally undermined by the processes that produce us all as what gilles deleuze has called ‘dividuals’ ( : ); aggregates of data distributed across multiple platforms that do not require the coherence of the individual to be meaningful. but, as i will demonstrate, dataviz as employed by corporations bidding for lucrative contracts or organisations concerned to reduce the complexity of large datasets, employs classical perspective to establish the veracity of what it represents. it thus reproduces the aesthetics of liberal humanism in the service of capital while being, at the same time, a significant actor in the discursive production of the dispersed and distributed digital self. this accords with what maurizio lazzarato refers to as the ‘twofold cynicism’ of contemporary capitalism, ‘the “humanist” cynicism of assigning us individuality’ and ‘the “dehumanizing” cynicism of including us in an assemblage that no longer distinguishes between human and non-human, subject and object, or words and things’ ( : ). it is not so much the case then that there is ‘no subject in fact’ but that algorithmic governmentality mobilises forces which usher into being new configurations of the subject which, as i will later argue, requires new critical methods to bring into focus the politics of the algorithm and its cultural effects. for now, it is enough to point out that the feedback that algorithms produce is far from uncontrolled. kantar, for instance, which bills itself as ‘the world’s leading data, insights and consulting company’ ( a) produces reports based on data mining, coupled with structured interviews and other forms of market research designed to enable the advertising industry to better target consumers. although this kind of research is as old as advertising itself, the speed with which data can now be mined for ‘insights’ and the increasingly fine-grained profiling of consumers makes the product that they offer uniquely valuable. data may be ‘big’ but what data mining promises is that tools will be provided through which it can be surveyed as a totality, mastered and forced to give up its valuable secrets. the promise of big data is, as david chandler suggests, that ‘the world (coded through datafication) can begin to speak for itself’ ( : ) without the necessity of interpretation. but, as orit halpern puts it, ‘there is nothing automatic, obvious, or predetermined about our embrace of data as wealth. there is, in fact, an aesthetic crafting to this knowledge, a performance necessary to produce value’ ( : ). in other words, data may allow the world to ‘speak for itself’ but, in order for it to be made meaningful as a product at point-of-sale, its ‘speech’ is pre-coded through a set of representational practices. these, as anthony mccosker and rowan wilken have suggested, draw on predetermined ideas of ‘beauty’ which refer to the kantian mathematical sublime: the aesthetic satisfaction derived from elegant representations of large and complex numerical data which cannot ordinarily be comprehended ( : – ). kantar hosts the yearly information is beautiful awards, held to celebrate ‘awesomeness in data vizualisation and infographics across the world’ ( b). ‘gold’ winners in , among many others, included a graphic representation of recurring themes and motifs in the work of pablo picasso, a sound and vision interactive mapping of ‘fan energy’ during a football game and a colour coded scrolling map of land use in the united states. the winner of the ‘most beautiful’ category was simulated dendrochronology of u.s. immigration – (cruz et al. a) which uses the visual metaphor of colour coded tree rings to image the historical growth of immigration to the us, where the colours represent the regions of the world which have done most to swell the us population in any given period. rings for individual states and segments of history can be abstracted and it is also possible to see the difference in growth between new immigrants and increases in population due to ‘natural borns’ (children born in the us). the visual is complex, able to yield a number of differently inflected results and crafted according to design principles which deliberately suggest ‘natural’ growth (the soundtrack of the accompanying video is bird sounds and rushing water). indeed, the designers state that their decision to image quanta of immigration statistics as ‘cells’ deposited during aeons of tree growth was motivated by ‘the idea that these marks in the past are immutable and cannot be erased regardless how you read them. additionally, it embodies the concept that all cells contributed to the organism’s growth and that they are all part of it’ (cruz et al. b). the intention, then, is to appropriate big data aesthetics to counter populist rhetoric which pits a supposed indigenous ‘us’ against a maligned immigrant ‘them’. however, the form of presentation, as i will show, tends to mitigate these laudable intentions. in her study of the corporate data industry, melissa gregg found that the medium overcame the message to the extent that, in one presentation that she attended, visualisations were offered that no actual datasets had been employed to develop. what was being promoted then was a persuasive aesthetic that could be applied to any number or type of dataset with any presumed audience. thus ‘in corporate settings, the possibility of data visualisation is regularly celebrated at the expense of considering the materiality of that which is processed’ ( : ). despite the fact that simulated dendrochronology is not aimed at the corporate market, i would argue that similar considerations apply. it simulates the retrieval of history in a form which gains the status of undisputed truth through its association with the instrumental value of big data while offering a form of knowledge which is literally naturalised by its presentation in images of organic growth. at the same time, it flattens the terrain of race to imply that immigration to the us has been seamless and that assimilation is the norm. tree-rings notwithstanding, the form of simulated dendrochronology in fact, refers to and animates, both literally and figuratively, a visual rhetoric established in the statistical atlases published in the us in the early twentieth century through which data about the distribution of races across states and among eg., occupations could be read off easily by diverse audiences. these ‘[c]lean, geometric forms’, as charles kostelnick suggests, ‘supplied a basic design vocabulary for implementing the modernist program, engendering an aesthetic of cultural homogeneity that dovetailed with the melting-pot ideology of early th-century america’ ( : ) and developing ‘a conventional visual language for displaying data which built ‘a rhetorical bridge to contemporary information design’ ( : ). the idea of the melting-pot and the forms through which it is communicated can be seen to establish a standard both for how information about immigration is received and the viewing subject who receives it. citizens schooled in the visual literacy of these forms are performing a ritual of self-recognition through which they are established as in conformity with a normalised ontology. thus the selective sifting of data which is the quintessential function of algorithms and which is, in corporate settings, structured to produce value is, in simulated dendrochronology, employed to strategically simulate a version of us history which accords with the mythology of colonialism. put another way, the graphic here is read through the discourse of colonialism, supported by and entangled with algorithmic governmentality. with this in mind, my proposition is that the pleasure of viewing dataviz is derived from what i will continue to refer to as the aesthetics of retrieval to stand for the way in which data becomes beautiful through the graphic performance of a conditioned abstraction from the noise of the world. this describes the ‘crafting’ to which halpern refers while encoding the sense that information is knowledge and is only waiting the appropriate retrieval mechanism to be realised and made available to perception. in fact, i intend the aesthetics of retrieval to have a dual meaning; referring both to the way that dataviz is crafted to assure the value of what is retrieved from the churning archive of digital culture while also, as i will continue to argue, suggesting the affordances of what is not retrieved by the algorithms that do their work only in the name of profit. the aesthetics of retrieval the representational logic of retrieval, i would suggest, offers access to what lazzarato calls (following félix guattari) ‘asignifying semiotics’ ( : ) which function to destabilise the systems of meaning through which language operates to determine subject formation. asignifying semiotics are found in languages (including, but not limited to, computer languages) and are, as he says, ‘a matter of assemblages where man (sic), language and consciousness no longer have priority’ ( ) and which ‘constitute the semiotics of an economy of possibles’ ( ). with reference to simulated dendrochronology, we could say that it derives its ‘beauty’ from an attempt to reterritorialize the asignifying semiotics from which it is produced and subject them to representation. like cinema, which (again, following guattari) lazzarato points out is an always already deterritorialized art form which has nevertheless been subjected by the culture industry to reterritorialization through the exploitation of ‘like psychoanalysis, personological and familialist signifiers’, so the ‘crafting’ of simulated dendrochronology attempts to reduce ‘asignifying semiotics to the models of capitalist subjectivity’ ( : ). for lazzarato the imperative is to ‘free the human and non-human forces that the first industrial revolution imprisoned in labor, language, and life, and do so not in order to find an “original” subjectivity, but to open and activate other processes of its production’ ( : , emphasis in original). in other words, asignifying semiotics code an interrogation of what braidotti calls ‘the self-representations and conventional understandings of being human, which “we” have inherited from the past’ ( : ). what is at stake here is the set of assumptions which had always ensured the category ‘human’ as a baseline measurement for all other ontological forms. it is this, i will argue, that is realised in the way that the aesthetics of retrieval activate both the coherent and consistent subject that the promise of synoptic vision confirms and the possibilities inherent in the realisation that there is ‘no subject in fact’. in what follows, i will propose that glitch art functions to expose the potential of asignifying semiotics in the form of the excess which cybernetic capitalism both requires and disavows. this is the excess which constitutes the ‘grayness’ (fuller & goffey, : ) necessarily produced by all forms of processing and which matthew fuller and andrew goffey describe as the ‘digital equivalent of rotting offal’ and which presents ‘multiple occasions … for crafty … exploitation’ ( – ). glitch, i would suggest, in exploiting this excess, questions the self-evidence of the visible and re-frames data retrieval as an act of what jacques rancière calls ‘dissensus’ which ‘creates a fissure in the sensible order by confronting the established framework of perception, thought and action with the “inadmissible”’ ( : ). for rancière, ‘[t]here is no real world’. ‘instead’, he writes, ‘there are definite configurations of what is given as our real, as the object of our perceptions and the field of our interventions’ ( : ). glitch then marks out a space for dissensus where the configurations of data and their relationship to the real is made visible. in troubling those configurations it also troubles the ontologies to which they refer. it disturbs the sediment of what is forgotten or ignored; the remains that constitute the archive and which hold the promise of a different kind of retrieval and, just possibly, a different way of life. invention and breakdown in to our friends, the most recent of the invisible committee’s anonymously penned manifestos for social change they take a position which is echoed by, for instance, braidotti ( : – ) and which is the fundamental position from which posthuman politics proceeds. in broad agreement with lazzarato, they refer to a ‘cybernetic governmentality’ operating in terms of a ‘completely new logic’ while ‘its subjects continue to think of themselves according to the old paradigm’ ( : ). this is the paradigm represented by vitruvian man (braidotti : – ), the impossible template for modern man and his investment in optics as proxy for the individual as controlling centre of a private and self-directed universe. he is the architect as author of space, the artist as interpreter of the world, the scientist as guarantor of progress and, finally, the human as bearer of rational perspective which is also the human as manipulator of technical devices. what this entails is not only the categorical expulsion of any and all living things deemed a-rational but the illusion of a natural world, itself a-rational, which human entities are both a part of and able to control. but the division between natural and artificial and technical and organic is artificial in itself. or, as the invisible committee ( : ) put it, ‘our familiar world rarely appears to us as “technical” … because the set of artifices that structure it are already part of us’. crucially, they continue ‘the technical character of our world only stands out in two circumstances: invention and “breakdown.” it’s only when we’re present at a discovery or when a familiar element is lacking, or breaks, or stops functioning, that the illusion of living in a natural world gives way in the face of contrary evidence’. posthuman politics is attuned to this ‘contrary evidence’ and, in particular, to the frailty of the human as a category which guarantees ontological hierarchies. posthuman thought, as braidotti says, mobilises ‘resources and visions that have been left untapped’ ( : ) and is able to ‘make a qualitative leap out of the familiar’ ( ). this, as i will continue to argue, is the appeal of glitch; that it not only exposes the workings of the system and its ability to function otherwise but enables us to recognise ourselves as always already posthuman and thus not ‘natural’ subjects ranged against forces beyond our control but political actors subjectivised by those same forces and thus in a position to mobilise against them. i would designate glitch as an instance of what dimitris papadopoulos, niamh stephenson and vassilis tsianos call ‘imperceptible politics’ ( : ), the apprehension of moments when the absurdity and precarity of the entire system of production and its associated representations become visible, graspable, and open to creative exploitation. ‘the generative activity of the dataset’ as fuller and goffey point out, ‘is never completely assured in its outcomes, producing new forms of uncertainty and indeterminacy even as it accomplishes its allotted tasks of automation and control’ ( : ). glitch art exploits these moments of revelatory breakdown by appropriating the tools with which dataviz achieves its aesthetic crafting to structure an opposition which works with what rouvroy has called the ‘remnants’ ( : ) or what the data retrieval mechanisms of contemporary capitalism discard, disavow or conceal. glitch apocalypse glitch art works with the signals suppressed by – but a necessary supplement to – algorithmic processes. in working with this redundancy, it utilises the output from random operations to reveal the underlying dependency of the smooth surface of the digital image on a particular but contingent arrangement of nested and interlocking commands. the process is deliberately destructive, aiming to rupture the coherence of a digital artefact so that something other may emerge. in effect then, it deliberately introduces noise into communication, randomly re-assorting an ordered sequence to demonstrate that order itself is arbitrary, contingent and open to transduction. carolyn l. kane locates its historical precedents in, for instance, the way that painting responded to the visual accuracy of the photographic image in the late nineteenth and early twentieth centuries, singling out, for instance, futurism ‘which actively skewed and distorted the coherency of the composition’ ( : ). she also cites duchamp’s the bride stripped bare by her bachelors, even ( – ) a.k.a the large glass which, as she says ‘uses error and breakage to highlight what is normally invisible and functional in practices of looking and knowing, making visible what is otherwise an unconscious and ideological relation to knowledge and truth’ ( : ). for similar reasons the large glass also features in david campany’s essay ‘a handful of dust’, in which he emphasises how duchamp’s strategic use of random accumulations of dust (and dust breeding, man ray’s photograph (ray ) of the glass in production) are significant examples of a ‘preoccupation with the “stage wings” of modernity, with what progress must leave out or suppress’ ( : ). thus, glitch and its ‘compression aesthetics’ (kane : ) is an iteration of these tendencies which makes direct use of the technical processes of digital production to suggest a critique of data visualisations and their representations of forms of order through which information becomes commodified. the glitch aesthetic itself is not particularly new, as is well known by producers of ‘noise’ music, an artform that utilised the inherently glitchy early samplers and digital synthesisers that began to emerge in the s. sound designer kim cascone suggests that glitch originated as ‘a subversion of the smooth and technically perfect surface of digital audio’ and is ‘cognitively reacted to as a rupture in the continuum of an idealized artifact’ ( : ). put another way, glitch can be understood as a rupture in the spectacle effected through interference techniques attuned to the latent potential of redundancy, error, misdirection and randomness. with this in mind, it can be understood as exploiting the aesthetics of retrieval to reveal what is beneath the technically perfect surface, what is discarded to ensure that it retains its value; the excess which secures meaning but which also threatens it with redundancy. indeed, glitch artists themselves are prone to describe their work in terms which echo my analysis. post-photography practitioner sabato visconti ( ), for instance, situates glitch in the interstices of the digital production process which includes the techniques through which the digital camera and its firmware are made available for purchase and use through the iterations of the image as it is compressed, manipulated, corrected and viewed. nick briz, referring specifically to the systems architecture through which visual images are realised in a digital environment is concerned with the politics of glitch as an affront to the hegemony of corporate computing. ‘a glitch’, as he says, ‘is an unexpected moment in a system that calls attention to that system’, it ‘reveals aspects of that system which might otherwise go unnoticed (while the system attempts to remain “invisible”)’ (briz ). for philip stearns, glitch is ‘the unlocking of other worlds latent in the technologies with which we surround ourselves’ ( ). and rosa menkman, in her glitch studies manifesto, proposes the term ‘noise artifacts’ ( / : / ) to refer to the ‘fingerprints of imperfection’ ( / ) which are inherent in all technologies and which glitch retrieves and makes apparent. ‘the glitch is a wonderful experience of an interruption’, she writes, ‘that shifts an object away from its ordinary form and discourse … but somewhere within the destructed ruins of meaning hope exists; a triumphal sensation that there is something more than just devastation’ (ibid / ). michael betancourt suggests that the critical function of glitch is in that it reveals the materiality of machinic processes and, crucially, can be thought of as ‘unformed and unforeseen potential … which is inherent in the machine’ ( : ). relevant here also is hito steyerl’s assessment of ‘poor images’ as working to suggest a retrieval of what is discarded to produce what she refers to as ‘the fetish value of high resolution’ ( : ). poor images are low resolution (pirated) copies of cinema blockbusters, imperfectly digitised copies of old analogue films that never made it to dvd, ‘amateur’ video and photography, the many clip montages with ill-chosen soundtracks that litter youtube, gonzo pornography. all these (and more) are both the labour and product of the prosumer economy and what is other to, and guarantor of, the high exchange value of their high-resolution counterpart. they are its background hum; the noise which determines the signal – the debased term of an oppositional hierarchy. for steyerl, this ‘alternative economy of images’ has the potential to constitute an art of the multitude, constructing ‘anonymous global networks just as it creates a shared history’. ‘the poor image’, she writes, ‘ambivalent as its status may be—thus takes its place in the genealogy of carbon-copied pamphlets, cine-train agit-prop films, underground video magazines and other nonconformist materials, which aesthetically often used poor materials. moreover, it reactualizes many of the historical ideas associated with these circuits’ ( : ). glitch, i would argue, engages with the same sense of reactualisation, encoded as the play of errant pixels in its signature aesthetic. in a different register, evan calder williams echoes this idea in his concept of ‘salvagepunk’, a cultural formation fascinated by ruins, not as a nostalgic yearning for lost empires or a romantic attachment to natural decay but as an expression of potential. what he calls ‘apocalypse’ is ‘a wound of the present that exposes the unseen – but unhidden – from which after-work can begin to dig out all the failed starts, possible histories.’ ( : ) apocalypse, for calder williams, is a revelation of potential in ideas that refuse to die but have been obscured by totalising ideologies and the ‘universal ordering system’ which ensures that ‘certain things are worth seeing or even can be seen’. what he calls the ‘“undifferentiated” is that which cannot be seen’ ( : ). in other words, what cannot or must not be seen are what threaten to collapse oppositions and to throw into doubt sanctioned differentiations. apocalypse is, quite simply, the revelation of what we should have known all along, precipitated by a change in direction, a pause, a malfunction or, essentially, a glitch. thus another way to describe the aesthetics of retrieval might be through the deliberate strategy of forced breakdown in the service of revealing the undifferentiated which algorithmic governmentality both requires and disavows. it is also, crucially, a description of the pleasure of reading the undifferentiated in such a way as to destabilise the hegemony of ‘natural’ structures and their associated ontological determinacy. glitch practitioners are often dismayed at the leaky nature of contemporary media and the incorporation of glitch artefacts into pop video and film. kane, in particular, is scathing about kanye west’s glitchy welcome to heartbreak video which, as she says, ‘simulates a diy aesthetic, but is not actually derived from diy strategies, nor does it perform any real critique of pop-culture’ ( ) nevertheless, as campany points out ‘[t]he line between entertaining visual puzzles and troubling estrangement is very fine’ ( : ). if we are to take seriously kane’s suggestion that ‘[a] glitch or technical error can be used to pose questions and open up critical spaces in new and unforeseen ways’ ( ) then i would suggest that it is precisely in popular culture where we may make use of the appearance of the aesthetics of retrieval to inaugurate new forms of critique; to, in effect, expose the relationship between the form and content of screen media and the way that the process of subjectivation proceeds as an effect of digital capitalism. i want to conclude here then by exploring the emergence of noise artefacts into popular culture with a particular emphasis on denis villeneuve’s sequel to ridley scott’s blade runner ( / / ) and sam esmail’s tv series mr robot, both of which are about the loss of data and which also make judicious use of glitch to explore the power structures that condition subjectivities. noise artefacts arguably, one of the first glitch artefacts in popular culture was max headroom (figure ), a chat show host/vj spun off from a tv movie, max headroom: minutes into the future ( ), originally broadcast on channel in the uk ( – ). although max, from a twenty-first century point of view looks like a glitched data file, actor matt frewer’s ai alter-ego was actually created using prosthetics. figure looking like a ‘glitched data file’. max headroom. nevertheless, the premise of max headroom: that a human mind uploaded to a platform designed for broadcast television of the s (remember – this is only minutes into the future) would necessarily glitch but would also have the potential to subvert the medium of which it had become a part is instructive. leaving aside, for the moment, the debates which make a distinction between glitch art proper and ‘glitch-alike’ (moradi in betancourt, : ), my claim here is that max is a figure that, in his troubling of ontological certainties in the face of apocalypse, can offer a way to assess the critical function of glitch in popular culture in terms of its revelation of the posthuman subject, read through the aesthetics of retrieval. max, possibly the most annoying ‘character’ of s tv and now largely consigned to the archive of lost media and the more obscure corners of internet fandom is nevertheless him/itself, i would suggest, representative of how the ‘remnants’ or ‘false starts’ can be mobilised to interrogate the apparent seamlessness of the looping structures through which algorithmic governmentality operates. more recently, of course, glitch has emerged full blown into popular culture, perhaps lamentably collapsing the distinction between glitch as art and commercial forms which simulate or appropriate it (betancourt : ). nevertheless, blade runner seems to me to invite a reading in which glitch effects stand for more than simply appropriation of the form in an attempt to borrow authenticity. i have suggested elsewhere (shaw, ) that ridley scott’s original blade runner can be most productively read as a critique of hierarchies of being in that it images the effects of the collapse of distinctions on which they rely through an interrogation of the relationship between visual prosthetics and memory. in the sequel, set thirty years into the diagetic future, the employment of noise artefacts both troubles this relationship and, as i will demonstrate, opens new avenues of critique which work with the latent potential of breakdown and its cultural effects. the graphics accompanying the opening and closing credits of were produced, in fact, through a collaboration between video glitch artist anton marini (aka vade) and designer toros kose (marini and kose ). when i saw the film at the cinema, i honestly thought, at least for a moment, that the transmission was faulty. the shift to recognition of the glitch aesthetic was a moment of affective displacement or, to repeat menkman’s glitch experience, a ‘wonderful interruption’ where what was interrupted was the narrative of hollywood and its overdetermination as the factory of cultural meaning. the glitching of familiar hollywood and tech giant logos can be seen to render the ideas that they represent impermanent and corrupt. this is the ‘shift away from ordinary form and discourse’ to which menkman refers and it is a powerful introduction to a film about the function of technology in the crafting of memories. in the future of a rebel engineered data blackout has almost completely wiped the databanks of the world’s computers (watanabe ), leaving a gap in history and only fragments of the knowledge through which the famous ‘replicants’ of the original blade runner were created. rick deckard (harrison ford), now lives alone in a crumbling casino amid the ruins of las vegas where fragments of twentieth century culture survive as imperfect holograms of elvis, marilyn monroe and liberace in their prime, complete with chorus line. what is interesting here is not just the survival of twentieth century cultural artefacts but the significance of their degraded state: elvis winks out halfway through a line and re-appears for the next verse; marilyn flickers and stalls; the chorus line stutters mid-kick. on the surface, this is a representation of the degraded state of historical data in the film’s diagetic present which can also stand as commentary on the unreliable nature of memory. however, read through the aesthetics of retrieval, these noise artefacts in their random disruption of the smooth transmisson of data, insert a hesitation which draws attention to the machinery of image production. the system, in menkman’s words, exhibits ‘its formations, inner workings and flaws’ (menkman / : / ). this stands as an effective deconstruction of celebrity culture and its artifice but it also functions, like the glitchy delivery of max headroom, to destabilise the myth of technological utopia or the dream that a successor species will emerge from the confluence of human consciousness and the digital archive; what steve fuller refers to as ‘humanity . ’ ( ). this yearning for salvation through incorporation with advanced technology is currently the aim of multi-billion dollar projects investigating life extension through things like cryonic preservation, gene editing, nanotechnology, space migration and brain uploading. all of these projects, ultimately, are oriented towards the preservation of an essential humanity founded in an informational paradigm in which the brain is privileged as the organ of determination. in this scenario, the cumbersome body on which the violence of the state is enacted in the name of capital is dispensed with, modified or preserved as pure information while consciousness is retained in the form of digital encoding. this signals, as charles thorpe has pointed out, not only the triumph of abstract individualism but full mergence with etherized capital and thus a dispensation from the necessity to confront it ( : ). at the same time, what this scenario seems to require is the continuation of capitalism by any means necessary, including the use of dwindling natural resources. but blade runner is about lost knowledge, data that can never be retrieved and imperfect constructions of truth as read-out from the remaining fragments. the degraded holograms, representations of celebrities who, in their prime, promised a form of eternal life through their constant re-circulation as commodities are, in the face of structural breakdown, rendered redundant and monstrous. at the same time, the employment of glitch aesthetics, intentionally or not, points to the posthuman understood as a recognition of what we always already are, rather than what we hope to become. what is suggested is the promise of the undifferentiated where the aesthetics of retrieval activate an orientation towards to the future which does not imagine a perfected human condition reserved for the few at the expense of the many but a consciousness of imperceptible politics in the present and a commitment to working creatively with what emerges from the ruins. shortly after the film’s premiere, voices were raised in protest (smith ) over its portrayal of female characters, in particular the depiction of joi (ana de armas. figure ), the holographic ‘girlfriend’ who lives with k (ryan gosling), the replicant at the centre of the narrative. however, it is joi her/itself which most potently exposes the ‘inner workings’ of the system of gender. when k’s spinner crashes in the desert, joi, along for the ride thanks to the ‘emanator’ device that k has purchased to free her from the confines of his apartment, glitches in the act of showing proper girl-friendly concern for her injured lover, never quite completing the gesture. as the camera pulls back from the scene, there is real pathos in the exposure of her fragility, the glitch here functioning as proxy for the fragility, artifice and constructedness of gender itself. figure one in a series of ‘femine archetypes’: the fragility of glitch functioning as proxy for ‘artifice and constructedness of gender itself’. ana de armas as joi in blade runner . joi is mercurial, adaptable to k’s moods as she cycles through a series of feminine archetypes, conforming to her program which promises the perfect girlfriend experience, ‘everything you want to see, everything you want to hear…’. as a noise artefact, however, she is a foil for the ‘happy’ ending; the expectation of heterosexual completion in the normatively constituted family scene. she is as redundant, in fact, as elvis, marilyn and all the absurdly remaining artefacts of las vegas in its prime represented, aside from the holograms, by giant tumbled mouldings of the idealised female form. holographic nostalgia is a familiar entertainment in the media saturated world of our current location in time, as are virtual girlfriends. but displaced to the ruins of the future, their struggle to maintain coherence exposes the fragility of what they attempt to figure; the ideal that they purport to model. similarly, in the final episode of sam esmail’s award winning series mr robot (figure ), glitch effects figure the dual meaning of memory disruption and dislocation which ground both the series’ narrative and its sub-text. for a large part of the first three seasons, elliot alderson (rami malek) is a drug addicted hacker with an enabling alter ego, called mr robot (christian slater), who may or may not be his father. in season , other characters emerge as manifestations of elliot’s dissociative personality disorder and the hack becomes a metaphor for the restructuring of the psyche necessary for him to re-engage with reality. mr robot is revealed as a memory retrieved from elliot’s childhood, put to work as an interface between elliot and the world he must navigate in his fight against globe-dominating digital behemoth e corp. thus distorted recall and the function of memory in the structure of the personality are integral to the text and these are presented as inseparable from data retrieval as a function of cybernetic capitalism. figure rami malek in mr robot (glitched) – ‘memory disruption and dislocation’. on a banal level, the hack can be read as standing in for the clinical scene of psychoanalysis and its resolution in adjustment to psychic reality. however, a more nuanced reading becomes possible through the noise artefacts which make an appearance in the final episode, imaged as interference in the transmission producing pixelated effects and time-space distortions. initially, what this tends to emphasise is a breakdown in elliot’s constructed reality and an orientation towards a new subjective horizon. but, equally, it can be read as enacting jacques derrida’s proposition, in archive fever, that ‘[a]rchivable meaning is also and in advance codetermined by the structure that archives’ ( : ). part of what derrida is suggesting here is a necessary relationship between the sedimentation of memory as a function of psychic conditioning, the social structures that determine meaning and the technical devices that enable the archive to exist. as in blade runner then, what mr robot makes available, and what the noise artefacts that it employs promote, is a ‘wonderful interruption’ in which ‘the structure that archives’ is exposed. the revelation of elliot’s self-administered therapy which he experiences as a series of sessions with another artefact of his personality, krista (gloria reuben), is not then adjustment to a pre-given reality but a recognition of disassociation as essential to subject positions as constructed by algorithmic governmentality. what i am discussing here then are what braidotti calls ‘conceptual personae … alternative representations of the subject as a dynamic non-unitary entity’ ( : ) which can stand for the posthuman as both a rejection of anthropocentrism and a move towards creative re-imaginings of what it means to be in a world where the boundaries between previously disparate entities are becoming increasingly fluid. glitch then is noise made manifest; a visual representation of what, if the system is functioning correctly, should not be seen. it is, equally, a retrieval but one which, in privileging noise over signal, provides for a response which is a recognition of the entire system of production as vulnerable to the excess which it necessarily represses in the aesthetic crafting of algorithmic truth. as betancourt points out ( : ), glitch realises the kind of aesthetic that theodor adorno claimed for modern art. its social function is, as adorno says, in its ‘functionlessness’ ( : ). it is thus in antagonistic relation to production and consequently to the reality represented by the culture industry. what i have suggested then is that this requires a new critical approach; a form of posthuman critical theory which works with the tension between the atomised human subject that algorithmic governmentality requires and a subjectivity that is emergent with that same system and is an effect of its attempts at global dominance. crucial here is the testing of these ideas in a critical appraisal of the products of popular culture which, in its attempts to incorporate the glitch aesthetic, also borrow its ‘wonderful interruptions’ that shift meaning away from teleological discourses. while, admittedly, both blade runner and mr robot are texts which incorporate critique at a narrative level, my analysis here is designed to probe further into what they offer as templates for a reappraisal of tactics for reading contemporary visual culture against the grain. put another way, the employment of the glitch aesthetic signifies posthuman subjectivity as an effect of apocalypse where ‘post’ does not stand for a successor species or the enhanced human but a subject position emergent with the system itself, coming to self-recognition through breakdown and attuned to imperceptible politics. what i have demonstrated here then is a methodology that can be employed towards a form of knowledge that proceeds from an ontological position in which ‘knowing subjects are collaboratively linked to a material web of human and non-human agents’ (braidotti, : ). this, of course, was always the case but a confluence of geophysical disasters has been necessary for us to begin to confront the entanglements with nature and machines that has brought us to doubt the viability of the human enterprise. under lockdown conditions in the time of covid- we have been forced to recognise that the spaces between bodies are matters of life and death and that the virtual spaces provided by networked computing are where we come closer while being further apart. we need no more stark reminder that, as braidotti puts it, what we call the ‘self’ is ‘a moveable assemblage within a common life-space’ ( : ). this space enacts an enfolded cartography, producing unlooked-for realities, previously only considered as indicators of systemic failure, whose emergent forms we must learn to read. the aesthetics of retrieval describes how this reading might proceed. notes see shaw posthuman urbanism ( ) for a more developed discussion of this idea. [^] this is true of many other applications which purport to simulate forms of reality. for a discussion of this in the context of facial recognition see ramon amaro’s ‘as if’: https://www.e-flux.com/architecture/becoming-digital/ /as-if. [^] betancourt ( : ) in glitch art suggests that the first was digital tv dinner, first broadcast in . [^] channel revived max briefly in to advertise their new digital channels. [^] see eg., the future of humanity institute at oxford university (https://www.fhi.ox.ac.uk) and the lifeboat foundation (which partly raises money through automatic donations via purchases on amazon): https://lifeboat.com. see also leo hickman, ‘bioengineer humans to tackle climate change, say philosophers’ the guardian, march . available at: https://www.theguardian.com/environment/blog/ /mar/ /human-engineering-climate-change-philosophy?newsfeed=true. [^] acknowledgements with thanks, as ever, to stephen maddison for critical friendship. images: fig : max headroom ( – ): chrysalis/lakeside & lorimar productions/warner bros. fig : blade runner ( ): alcon entertainment/columbia pictures/sony. fig : mr robot ( – ): universal content productions/anonymous content/nbc universal television. competing interests the author has no competing interests to declare. author information debra benita shaw is a reader in cultural theory at the university of east london. she is the author of women, science and fiction ( ), technoculture: the key concepts ( ) and posthuman urbanism: mapping bodies in contemporary city space ( ). she is also co-director of the centre for cultural studies research and founding editor of the radical cultural studies book series published by rowman & littlefield international. references adorno, t. w. ( ). aesthetic theory. translated by robert hullot-kentor. london: continuum. betancourt, m. 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( ). printed ca. . available at: https://www.metmuseum.org/art/collection/search/ https://www.metmuseum.org/art/collection/search/ rouvroy, a., & stiegler, b. ( ). the digital regime of truth: from the algorithmic governmentality to a new rule of law. translated by a. nony and b. dillet. la deleuziana – online journal of philosophy (life and number), – . http://www.ladeleuziana.org/wp-content/uploads/ / /rouvroy-stiegler_eng.pdf http://www.ladeleuziana.org/wp-content/uploads/ / /rouvroy-stiegler_eng.pdf shaw, d. b. ( ). virtually human: replication and subjectivity in ridley scott’s blade runner. in w. h. kalaga & t. rachwal (eds.), signs of culture: simulacra and the real. frankfurt: peter lang. shaw, d. b. ( ). posthuman urbanism: mapping bodies in contemporary city space. london: rowman & littlefield international. smith, a. ( , oct ). is blade runner sexist – or a fair depiction of a dystopian future? the guardian. available at: https://www.theguardian.com/film/ /oct/ /is-blade-runner- -a-sexist-film-or-a-fair-depiction-of-a-dystopic-future https://www.theguardian.com/film/ /oct/ /is-blade-runner- -a-sexist-film-or-a-fair-depiction-of-a-dystopic-future stearns, p. ( ). year of the glitch. accessed june . available at: https://phillipstearns.wordpress.com/projects/year-of-the-glitch/ https://phillipstearns.wordpress.com/projects/year-of-the-glitch/ steyerl, h. ( ). in defense of the poor image. e-flux journal (november). available at: https://www.e-flux.com/journal/ / /in-defense-of-the-poor-image https://www.e-flux.com/journal/ / /in-defense-of-the-poor-image steyerl, h. ( ). duty free art: art in the age of planetary civil war. london: verso. thorpe, c. ( ). necroculture. new york: palgrave macmillan. doi: [doi: . / - - - - ] vade. ( ). blade runner . accessed june : http://vade.info/project.php?uuid=fb a c -f - cc-b - aa e http://vade.info/project.php?uuid=fb a c -f - cc-b - aa e villeneuve, d. ( ). blade runner film. alcon entertainment, columbia pictures. visconti, s. ( ). glitch photography as a practice in the age of postphotography. photography+glitch art+illustration, v . . available at: http://www.sabatobox.com/glitch-photography http://www.sabatobox.com/glitch-photography watanabe, s. (dir. ), blade runner: black out . alcon entertainment, cygames. download download xml download pdf issue volume • issue • jump to file checksums (md ) xml: c e f e c a ed db c pdf: ecb da b d c edc f fec harvard-style citation shaw, d. ( ) 'the aesthetics of retrieval: beautiful data, glitch art and popular culture', anthropocenes – human, inhuman, posthuman. ( ) : . doi: . /ahip. show: vancouver citation style | apa citation style × vancouver-style citation shaw, d. the aesthetics of retrieval: beautiful data, glitch art and popular culture. anthropocenes – human, inhuman, posthuman. ; ( ) : . doi: . /ahip. show: harvard citation style | apa citation style × apa-style citation shaw, d. ( , ). the aesthetics of retrieval: beautiful data, glitch art and popular culture. anthropocenes – human, inhuman, posthuman ( ) : . doi: . /ahip. show: harvard citation style | vancouver citation style × non specialist summary this article has no summary × | - | published by university of westminster press | privacy policy sitemap contact login google sites one account. all of google. sign in to continue to google sites enter your email find my account sign in with a different account create account one google account for everything google about google privacy terms help microsoft word - copertina - .docx american beauty: trade flows and export costs of us movies gianpiero meloni dimitri paolini juan de dios tena w o r k in g p a p e r s / c o n t r i b u t i d i r i c e r c a c r e n o s c e n t r o r i c e r c h e e c o n o m i c h e n o r d s u d ( c r e n o s ) u n i v e r s i t À d i c a g l i a r i u n i v e r s i t À d i s a s s a r i c r e n o s w a s s e t u p i n w i t h t h e p u r p o s e o f o r g a n i s i n g t h e j o i n t r e s e a r c h e f f o r t o f e c o n o m i s t s f r o m t h e t w o s a r d i n i a n u n i v e r s i t i e s ( c a g l i a r i a n d s a s s a r i ) i n v e s t i g a t i n g d u a l i s m a t t h e i n t e r n a t i o n a l a n d r e g i o n a l l e v e l . c r e n o s ’ p r i m a r y a i m i s t o i m p r o v e k n o w l e d g e o n t h e e c o n o m i c g a p b e t w e e n a r e a s a n d t o p r o v i d e u s e f u l i n f o r m a t i o n f o r p o l i c y i n t e r v e n t i o n . p a r t i c u l a r a t t e n t i o n i s p a i d t o t h e r o l e o f i n s t i t u t i o n s , t e c h n o l o g i c a l p r o g r e s s a n d d i f f u s i o n o f i n n o v a t i o n i n t h e p r o c e s s o f c o n v e r g e n c e o r d i v e r g e n c e b e t w e e n e c o n o m i c a r e a s . t o c a r r y o u t i t s r e s e a r c h , c r e n o s c o l l a b o r a t e s w i t h r e s e a r c h c e n t r e s a n d u n i v e r s i t i e s a t b o t h n a t i o n a l a n d i n t e r n a t i o n a l l e v e l . t h e c e n t r e i s a l s o a c t i v e i n t h e f i e l d o f s c i e n t i f i c d i s s e m i n a t i o n , o r g a n i z i n g c o n f e r e n c e s a n d w o r k s h o p s a l o n g w i t h o t h e r a c t i v i t i e s s u c h a s s e m i n a r s a n d s u m m e r s c h o o l s . c r e n o s c r e a t e s a n d m a n a g e s s e v e r a l d a t a b a s e s o f v a r i o u s s o c i o - e c o n o m i c v a r i a b l e s o n i t a l y a n d s a r d i n i a . a t t h e l o c a l l e v e l , c r e n o s p r o m o t e s a n d p a r t i c i p a t e s t o p r o j e c t s i m p a c t i n g o n t h e m o s t r e l e v a n t i s s u e s i n t h e s a r d i n i a n e c o n o m y , s u c h a s t o u r i s m , e n v i r o n m e n t , t r a n s p o r t s a n d m a c r o e c o n o m i c f o r e c a s t s . w w w . c r e n o s . i t i n f o @ c r e n o s . i t c r e n o s – c a g l i a r i v i a s a n g i o r g i o , i - c a g l i a r i , i t a l i a t e l . + - - ; f a x + - - c r e n o s - s a s s a r i v i a t o r r e t o n d a , i - s a s s a r i , i t a l i a t e l . + - - ; f a x + - - t i t l e : a m e r i c a n b e a u t y : t r a d e f l o w s a n d e x p o r t c o s t s o f u s m o v i e s f i r s t e d i t i o n : n o v e m b e r s e c o n d e d i t i o n : j u l y american beauty: trade flows and export costs of us movies gianpiero meloni university of sassari and crenos dimitri paolini university of sassari, crenos and core juan de dios tena universidad carlos iii de madrid, university of sassari and crenos abstract copyright industries face global fixed export costs, in terms of cultural and geographic distance together with formal trade barriers. adjustment to these costs may occur along both the intensive and the extensive margin. we investigate this issue using a microeconomic approach that considers a hedonic model of revenues for us movie exports to evaluate: aggregation bias; simultaneity in the observation of imported movies and their revenues; and reliable estimations for country clusters. we find that product heterogeneity is a key element for both intensive and extensive margin adjustments at the country level. keywords: trade, export costs, movie industry jel classification: l , f introduction this article investigates recent issues in international trade literature on export costs: how much countries characteristics and product heterogene- ity impact on the extensive (numbers of products exported) and intensive (value of trade per product) margins. in a framework with firm heterogeneity and high fixed costs, only large and highly productive firms choose to export (bernard and jensen, , and melitz, ). hanson and xiang ( ) document that in this scenario: ”adjustment in trade volumes may occur along both the intensive margin and extensive margin”.their paper analyzes whether this paradigm also applies to fixed costs in the information service sector, by estimating intensive and extensive margin adjustments at the country level, for us motion picture data. their argument is that production costs are typically incurred in the country of production instead of the country of consump- tion, while transportation costs in the service industry are close to nil. moreover, additional marketing costs incurred for exports are likely to add much more to revenues than to costs (marvasti and canterbery, ). however, these industries can face other types of fixed costs that are more global. they would be related to establishing an international network in the exporting countries and could be expressed as a function of cultural and geographic distances, as well as other measures of trade barriers. ad- justment to these types of cost should occur along the intensive rather than the extensive margin and their empirical results are consistent with this hy- pothesis. they show that the numbers of movies imported in nations like argentina and germany are relatively similar whereas large differences can be observed in the box offices revenues in the two countries. in addition, their estimation of two equations for the number of us movies and the ratio of revenues to movies, reveals that the nature of fixed export costs is global and consistent with intensive margin adjustment. we explore this issue with a microeconomic approach by estimating a he- donic model of us movies revenues in foreign markets. using a database of movies exhibited in countries between and , we study the factors that affect the probability of exhibition (extensive margin) and box office revenues (intensive margin) within a heckit framework. countries included in the sample are: argentina, australia, austria, belgium, brazil, bulgaria, chile, china, colombia, croatia, czech republic, denmark, domini- can republic, ecuador, egypt, estonia, finland, france, germany, greece, hungary, india, indonesia, israel, italy, jamaica, japan, kuwait, malaysia, mexico, netherlands, new zealand, norway, portugal, russia, slovakia, slovenia, south africa, south korea, spain, sweden, thailand, turkey, united kingdom, uruguay. this topic has been addressed, for a smaller group of countries, in previous papers such as fu and lee ( ) for singapore, lee ( , ) for east asian countries and walls and mckenzie ( ) for a group of six developed countries. the latter also to preview the results, we find that in general the nature of the cost is contingent on the type of country. thus, we present evidence of intensive margin adjustments for more developed nations that are culturally close to the us. at the other extreme are less developed countries that are also relatively distant from the american culture. in this case, the results are consistent with the presence of extensive adjustments due to the high fixed costs induced by cultural distance. the last group consists of either less developed countries that are culturally close to the us or developed coun- tries that are relatively distant from american culture. in this case, we find the presence of extensive margin adjustments, but, due to the lim- ited size of the market, the expected revenue of introducing new american movies is a decreasing function of their probability of arrival. moreover, preliminary data analysis and estimation results give evidence of the im- pact of movies idiosyncratic characteristics on both extensive and intensive margins, highlighting that product heterogeneity is a crucial aspect in pro- duction companies export strategies. the heckman approach and the use of such a detailed information set, is relevant for at least three reasons. first, a country estimation frame- work could potentially be affected by an aggregation bias problem since it cannot control the large heterogeneity of films with different features in terms of quality, genre and content. the proposed approach is also useful to determine the relative importance for these factors in the intensive and extensive margin adjustments. in addition, the fact that the number of movies exhibited and their revenues are simultaneously observed can pro- duce a bias problem in a regression for the two variables at the country level. instead, the estimation of a heckit model allows to estimate the adjustment of us films at the intensive and extensive margin in separate equations. therefore, the primary equation contains country-specific trend components in order to control for unobserved national characteristics such as trade barriers or national film production, as well as the inverse mills ratio to check for other potential sources of self selection. model identifi- cation is achieved by considering information on whether the most similar movie to each given film, the nearest neighbor, was exhibited in that coun- try two years earlier. a final reason to follow a microeconomic approach at the film level is that the large number of observations make it possible to consider sound estimations for specific clusters of countries. the next section presents the methodological framework and estimation strategy. in section we review the dataset and discuss the preliminary results, while section presents the estimation of the model. final conclu- sions are drawn in the last segment of the paper. implements the heckman procedure. methodology we analyze the intensive and extensive margin adjustments in the context of the us movie industry by estimating a hedonic model of revenues. a general approach in the literature is to explain film success as a function of production budgets, awards and different features of the film such as sequels, genre, content and so on. this approach is particularly sound when it is applied to countries other than the us, given that although the different explanatory indicators may fail to be exogenous in the american market (due to effects caused by the expected revenue) they can generally be considered as exogenous with respect to the revenue in each foreign country. each movie is observed in one particular year only, so it is not possible to specify a dynamic panel model. however, should be noted that the average box office revenue for each country could be affected by an unobserved specific trend component of domestic film production or national business cycle. therefore, our baseline specification explains the revenue of a film in a country j (in logs and adjusted for inflation) as a function of three main groups of variables: ( ) indicators for the quality of the film, the budget and award nominations, where the former is a measure of the production effort and the latter is a proxy of the artistic quality; ( ) variables related to the different features of the film in order to determine how these features impact its success; and ( ) a national trend component. the following model is considered ln revenueij = β + β ln budgeti + β nominationi + β gi + β pgi + β ri + β sequeli + β sequel i + β dramai + β actioni + β thrilleri + β originali + γjt + εij ( ) where i and j stand for film and country respectively, the terms βr for r = to are parameters of the model, γjt is a specific fixed effect component for country j at time t and εij is an error term. despite the fact that our national specific trend component already con- trols for the impact of other variables not included in the model at the country level , the potential problem of an endogenous sample selection is still possible, given that the probability of exhibition could be a function of some film-specific shadow costs or features. this may lead to inconsistent estimates of the coefficients in a model that accounts for film revenues if see mckenzie ( ) and the references therein the variables pg i and comedyi are left outside of the age rating and genre groups, respectively, to avoid perfect multicollinearity such as, for example, total production or demand in the national movie industry or the degree of protective legislation for the national industry. the shocks that affect the probability that a given movie is exhibited in a certain country are highly correlated with the shocks that determine its revenue. based on this premise, we employ heckman’s ( ) two-step methodology. in the first step, we estimate a probit model (selection equa- tion) for the probability that a film is exhibited in a given country. this approach allows us to obtain the mills ratios that are necessary to correct the ols estimates of the primary equation in stage two. to identify the model, it is necessary to choose at least one variable to be included in the selection equation only at the first stage. a natural choice of instrument is to define a variable that takes value one when the most similar movie was shown in that country two years before and zero otherwise. from statistical learning field we adopt the k-nearest neigh- bor approach to define a variable that minimizes the canonical distance of each film from all of the other movies released in a country two years prior using all of the covariates defined in equation ( ). in this way, we are able to identify similar movies across the sample given their quality and idiosyncratic features, such as genre, content and source. to implement the nearest neighbor, the first two years of the dataset ( and ) are drawn out of the sample and used as a training population to instruct the algorithm, thus reducing the test sample to movies. using a dummy variable, we assign value of if the most similar movie was released in the same country two years before, that is choosing a single neighbor for each case. the time lag is set based on the average time of production of a movie, so that production companies can react properly to the performance of previously released films and strategically choose what types of movies to promote in different markets. in section , we examine the estimation results for several clusters of coun- tries around two dimensions: human development index (hdi henceforth) and cultural distance (cd henceforth). the hdi is an index created by the united nations that summarizes measures of average achievement in key dimensions of human development: standards of living, education, life expectancy, quality of life and also information on the per capita gdp for each country. to capture information about the cultural distance between the us and each of the countries in the sample, we follow lee ( ) and implement a value-based index developed by hofstede ( ) that is built around four dimensions: ) power distance, which expresses the degree to which the less powerful members of a society accept and expect that power is dis- see altman ( ). we have also tested for broader neighbors, k = and k = , and did not find any improvements in the quality of our analysis. the results of this experiments and all of the other estimations not explicitly reported in this paper can be obtained from the authors upon request. tributed unequally; ) uncertainty avoidance, which expresses the degree to which the members of a society feel uncomfortable with uncertainty and ambiguity; ) individualism versus collectivism and ) masculinity versus femininity. we gathered this information from hofstede ( ) and then each country’s cultural distance from the united states was computed using kogut and singh’s ( ) formula: cdj = ∑ i= { (iij − iiu) /vi } / ( ) where cdj is the cultural distance of country j from the united states, iij is the value for country j on the ith cultural dimension (iiu for the us) and vi is the variance of the ith cultural dimension. last, in order to evaluate geographic distance (gd) we use data from cepii’s geodist database and in particular weighted distances between countries, calculated on bi- lateral distances of the biggest cities of two countries and those inter-city distances being weighted by the share of the city in the overall country’s population. data we evaluate the demand for us movies in countries using the box office revenues of films released over the period from - . data on box office revenues are available from boxofficemojo.com. we consider two types of variables, quality variables, such as production budget (adjusted for inflation, base year ) and academy awards nominations in one or more of the main categories: best movie, best director, best actor or actress in a leading or supporting role or best animation movie, and vari- ables of the idiosyncratic features of each title, in particular genres, mpaa ratings , sequels and sources. we gathered these data from opusdata.com and imdb.com, while production budget information comes from thenum- bers.com . we stress the fact that our data focus on countries that span the whole planet, with broad variance in terms of holiday periods and weather that see notes on cepii’s distance measures: the geodist database, mayer and zignano ( ) movie ratings provide parents with advance information about the content of movies to help them determine what is appropriate for their children. they are used in our sample as a proxy of the content of a movie in terms of violence, sex etc. g stands for general audiences; pg stands for parental guidance suggested; pg- stands for parents strongly cautioned; r stands for restricted, under requires accompanying parent or adult guardian see http://www.the-numbers.com/movie/budgets/all could affect local demand and potentially lead to differences in the the- atrical release dates of movies (see einav , and belleflamme and paolini, ). therefore, we choose not to explicitly address seasonality issues and timing strategies applied by distribution companies to maximize the box office performance of their products. insert table here insert figure here table shows the descriptive statistics for the variables under analysis for the whole sample period. note that excluding production budget, all of the others are dichotomous variables. figure plots log revenues per us movies against log number of movies exhibited by each country between and (expressed as deviation from the sample mean). the graph shows variation among both the ex- tensive and intensive margin. the phenomenon is greater for the latter, however the presence of several countries that import far fewer movies with respect to the sample mean ( movies) like china, dominican republic, india, jamaica and kuwait. should be noted, for what concerns china, this can be explained with strong trade barriers that limit movies import at per year. insert figure here figure expands this analysis of intensive and extensive margins adjust- ments dividing us movies by genres (action, comedy, drama and thriller). plots give evidence of broad variation in both the extensive and intensive margins for comedies and dramas, while action and thrillers movies are more clustered around the means in the number of movies imported and the relative box office revenues. we can interpret these patterns from the per- spective of product heterogeneity: comedies and dramas exhibit stronger correlation to american culture in terms of themes, characters and humor. in the econometric analysis of section we consider this heterogeneity in order to identify possible shadow costs at the film level. another aspect to take into account when looking at movies characteristics, and therefore at the implicit heterogeneity, is the production budget. left plot in figure fits the extensive margin against the log production budget (again expressed as deviation from the sample mean) and shows a strong statistical significance with a negative slope. this suggests that countries that import fewer movies tend to prefer those with relatively higher bud- gets . insert figure here the correlation between box office revenues and production budgets is weak and not statistically significant, suggesting that budget alone can- not explain movie success and we need to pair it with other idiosyncratic characteristics of a motion picture (genres, sequel and so on). this evidence is coherent with the results of devany ( ) where it is found that the relationship between a motion picture’s cost and revenue is wildly unpre- dictable compared to other investments due to the heterogeneity in movie performance with box office revenues exhibiting heavy right tails. insert figure here to turn our attention to importing countries characteristics, in figure we consider the role of cultural distance from the us and human develop- ment attainments. with the sole exception of hdi against the number of us movies imported, which suggests that more developed countries have a bigger market size for foreign products, cd and hdi alone cannot explain trade at the macro level. this is coherent with the findings in hanson and xiang ( ) concerning linguistic dissimilarities and geographic distance from the us. the methodological framework presented in the previous section grant us the possibility to fully explore the determinants of american motion pic- tures in foreign markets. results the first two columns of table show the estimation results of model ( ) in a pool regression for the countries in the sample for both the selection and primary equations. the statistical significance of the coefficient asso- ciated with the inverse mills ratio suggests the possible presence of sample selection bias. its negative sign is consistent with the assumption that, in for countries with strong trade barriers, like china, an alternative explanation could be that production companies offer a limited pool of movies to choose from, in particular big budget titles for which higher revenues are expected. in the words of the author: ”the movie industry is a profoundly uncertain business. the probability distributions of movie box office revenues and profits are characterized by heavy tails and infinite variance! it is hard to imagine making choices in more difficult circumstances. past success does not predict future success. forecasts of expected revenues are meaningless because the possibilities do not converge on a mean; they diverge over the entire outcome space with an infinite variance. this explains precisely why ”nobody knows anything” in the movie business”. some countries, the demand for american movies has a constrained size, which implies that a saturation of the market can occur, thus lowering the expected revenue for each movie exhibited. to control for the potential correlation of the error term in the primary and the selection equations we also considered the mundlak-chamberlain approach as proposed by wooldridge ( ), but it showed no qualitative change in the estimated results. for the sake of brevity, in this paper, we show our baseline specification which is based on a unique estimated in- verse mills ratio for the entire sample period. when we look at movie-specific variables, the relevant and positive impact of covariates on quality (production budget and academy awards nom- inations) can be observed in both the probability of exhibition and the revenue. as for genres, a global preference for action and thriller movies emerges with respect to the reference category of comedies. this result is consistent with the findings of lee ( ) and the empirical evidence (see the economist ) that american humor does not sell well in markets that exhibit a broad cultural distance from the united states. moreover, the positive impact that sequels and subsequent movies in a series have on revenues confirms the validity of hollywood’s actual strategy to invest in existing intellectual proprieties instead of introducing new, original prod- ucts into the market. the validity of this strategy is supported by the small magnitude of the coefficient associated with original screenplays which re- fer to movies in which the plot and characters are not part of a previous intellectual propriety (e.g. books, comics or video games). insert table here columns and of table show model ( ) augmented by some typi- cal indicators of distance that have also been considered in the literature, geographic distance (gd), hdi and cd . according to hanson and xian ( ), distance indicators should exert a more significant impact on the intensive margin (primary equation) than on the extensive one (selection equation). it can be observed that this proposition is only true in the case of gd which is only significant in the primary equation, while cultural dis- tance is a relevant variable in both equations. this result suggests that it is cd, and not gd, that represents an important bilateral fixed shadow cost to introduce a movie in a given country. in addition, the estimated model suggests that not only distance indicators but also the degree of de- velopment of a country is an important variable in determining both the number of films exhibited and their expected revenues. however, from data analysis in section , we recall that cd and hdi alone cannot explain movies success, an aspect here confirmed by the associated ”hollywood goes global. bigger abroad.” the economist, feb th . t-statistics, which we further explore performing a shapley value analy- sis . this approach allows us to disentangle the r by groups of variables to evaluate their relative impact on the model. we find that countries char- acteristics (cd, hdi and gd) globally account for less than % of the r , while the inverse mills ratio, that represents the selection hazard, explains % of the goodness of fit of the model and movie related variables impact for %. insert table here previous results do not exclude the possibility of different types of ad- justments at the intensive and extensive margins for different clusters of countries. to control for these aspects, we break down the total sample of countries according to their hdi and cd (the most significant indicators of distance) and show the estimation of equation ( ) for the different clusters of countries in table . in this case, the results from the probit model estimation are not reported for the sake of brevity, but the results show that the qualitative impact of all the variables is similar to their estimated effect in the primary equation. in general, according to the estimation re- sults, we can split the countries into three large groups when we consider intensive and extensive margins adjustments. first, countries with a low cd and a high hdi are characterized by inten- sive margin adjustment dominance (we cannot reject the random sample null hypothesis). in fact, it is reasonable to assume that these countries have low fixed costs and large markets where there is room for a substantial number of american films. the second relevant group of countries is that with a high cd and a high hdi. in this case, the results are consistent with the presence of extensive adjustments due to the high fixed costs in- duced by cultural distance. however, in this case, the estimated positive coefficient associated with the inverse mills ratio, indicates a positive re- lationship between the probability of film arrival and its revenue, which is consistent with the presence of a large national market for films. finally, the last group is composed of countries with a low hdi, regardless of their cd, in which there is evidence of sample selection bias with a negative inverse mills ratio coefficient. due to the presence of high fixed costs or the small size of the national market, the expected revenue of introducing new american films is a decreasing function of their probability of arrival. for what concerns movie specific variables and how groups of countries react to them, we can draw several conclusions: first of all, the impact of quality (expressed by academy awards nominations) is greater for more developed countries, while production budgets positively affect box office revenues in a similar way for all countries groups. in addition, we can see huettner and sunder ( ). see that producing sequels is a profitable strategy in each type of market, but promoting a series (third and subsequent movies in a franchise) grants bigger revenues in more developed countries. discussion copyright industries face fixed export costs due to cultural and geographic distances with importing countries, along with trade barriers. we study how these costs impact the number of products exported and the relative value per trade with a microeconomic approach by estimating a hedonic model of us movies revenues in foreign markets. this strategy delivers an improved quality of the econometric estimations and, more importantly, allows us to estimate intensive and extensive margins adjustments for dif- ferent clusters of countries. recent contributions in the field show that ”trade in movies adjusts pri- marily along the intensive margin. even small countries import a large number of us movies, leaving only modest variation in the extensive mar- gin of trade” (hanson and xiang, ). we give evidence of adjustments in the extensive margin when controlling for heterogeneity at the film level: countries in the sample exhibit different tastes for different genres with a broad variation in the number of movies imported for comedies and dra- mas. estimation results for clusters of countries built around cultural distance and human development attainment dimensions are characterized by in- tensive margin adjustment dominance, explained by wide differences in the impact of movies idiosyncratic characteristics. these findings suggest that product heterogeneity is a key element when evaluating trade costs in the information service sector, given its impact on both the number of products exported and the associated trade value. therefore some interesting topics for future research consist of extending this type of analysis to other copy- right industries or exploring the implications of these results for different marketing strategies of american film producers. references altman, n. s. 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( ). ”australian films at the australian box office: performance, distribution, and subsidies”. journal of cultural economics, ( ): - wooldridge j.m ( ). ”econometric analysis of cross section and panel data”. mit press. tables table : movies descriptive statistics ( - ) variable n mean std. deviation min max budget (adjusted) . . . . genres drama . . comedy . action . thriller . ratings g . . pg . pg- . r . sequel . sequel . nomination . original screenplay . t a b le : d et er m in a n ts o f m o v ie s re v en u es ( ) ( ) se le ct io n p ri m a ry se le ct io n p ri m a ry n ea re st n ei g h b o r . * * * ( . ) . * * * ( . ) h d i . * * * ( . ) . * * * ( . ) cu lt u ra l d is ta n ce - . * * * (- . ) - . * * * (- . ) g eo g ra p h ic d is ta n ce . ( . ) - . * * * (- . ) b u d g et . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) n o m in a ti o n . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) se q u el . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) se q u el . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) a ct io n . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) d ra m a - . * (- . ) - . * * * (- . ) - . * (- . ) - . * * * (- . ) th ri ll er . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) g - . * (- . ) . * * * ( . ) - . * (- . ) . * * * ( . ) p g - . * * * (- . ) . * * * ( . ) - . * * * (- . ) . * * * ( . ) r - . * * (- . ) - . * * (- . ) - . * * (- . ) - . * * * (- . ) o ri g in a l sc re en p la y . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) in v er se m il ls r a ti o - . * * * (- . ) - . * * * (- . ) n p se u d o r . . a d ju st ed r . . o m it te d : co m ed y, p g - ; t st a ti st ic s in p a re n th es es . (* ) p < . , (* * ) p < . , (* * * ) p < . t a b le : m o v ie s re v en u es - c d a n d h d i cl u st er s lo w c d h ig h c d lo w h d i h ig h h d i lo w h d i h ig h h d i in v er se m il ls r a ti o - . * * * (- . ) . ( . ) - . * * * (- . ) . * * * ( . ) b u d g et . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) n o m in a ti o n . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) se q u el . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) se q u el . * * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) a ct io n . * * ( . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) d ra m a - . * * * (- . ) - . * * * (- . ) - . * * * (- . ) - . (- . ) th ri ll er - . (- . ) . * * * ( . ) . * * * ( . ) . * * * ( . ) g . ( . ) . * * * ( . ) - . (- . ) - . (- . ) p g . ( . ) . ( . ) . * * * ( . ) - . (- . ) r - . (- . ) . ( . ) - . * * * (- . ) - . (- . ) o ri g in a l sc re en p la y . ( . ) . ( . ) . * * * ( . ) . ( . ) n a d ju st ed r . . . . o m it te d : co m ed y, p g - ; t st a ti st ic s in p a re n th es es . (* ) p < . , (* * ) p < . , (* * * ) p < . c o u n tr ie s in ea ch cl u st er : ( ) a rg en ti n a , d o m in ic a n r ep u b li c, h u n g a ry , in d ia , j a m a ic a , s o u th a fr ic a . ( ) a u st ra li a , a u st ri a , b el g iu m , c ze ch r ep u b li c, d en m a rk , e st o n ia , f in la n d , f ra n ce , g er m a n y, is ra el , it a ly , n et h er la n d s, n ew z ea la n d , n o rw a y, p o la n d , s p a in , s w ed en , u n it ed k in g d o m . ( ) b ra zi l, b u lg a ri a , c h il e, c h in a , c o lo m b ia , c ro a ti a , e cu a d o r, e g y p t, in d o n es ia , k u w a it , m a la y si a m ex ic o , p o rt u g a l, r u ss ia , t h a il a n d , t u rk ey , u ru g u a y. ( ) g re ec e, j a p a n , s lo v a k ia , s lo v en ia , s o u th k o re a . figures figure : intensive versus extensive margin of movie imports, - figure : intensive versus extensive margin of movie imports by genre, - figure : intensive/extensive margin versus production budget, - figure : intensive/extensive margin versus cd/hdi, - ultimi contributi di ricerca crenos i paper sono disponibili in: uhttp://www.crenos.itu / s i l v i a b a l i a , r i n a l d o b r a u , e m a n u e l a m a r r o c u “ f r e e p a t i e n t m o b i l i t y i s n o t a f r e e l u n c h . l e s s o n s f r o m a d e c e n t r a l i s e d n h s ” / g e r a r d o m a r l e t t o , “ a d e l i b e r a t i v e - p a r t i c i p a t i v e p r o c e d u r e f o r s u s t a i n a b l e u r b a n m o b i l i t y – f i n d i n g s f r o m a t e s t i n b a r i ( i t a l y ) ” / m a n u e l a d e i d d a , “ i n s u l a r i t y a n d e c o n o m i c d e v e l o p m e n t : a s u r v e y ” / e d o a r d o o t r a n t o , m a s s i m o m u c c i a r d i , p i e t r o b e r t u c c e l l i “ s p a t i a l e f f e c t s i n d y n a m i c c o n d i t i o n a l c o r r e l a t i o n s ” / f r a n c e s c o q u a t r a r o , s t e f a n o u s a i , “ a r e k n o w l e d g e f l o w s a l l a l i k e ? e v i d e n c e f r o m e u r o p e a n r e g i o n s ” / a n g e l o a n t o c i , f a b i o s a b a t i n i , m a u r o s o d i n i “ o n l i n e a n d o f f l i n e s o c i a l p a r t i c i p a t i o n a n d s o c i a l p o v e r t y t r a p s . c a n s o c i a l n e t w o r k s s a v e h u m a n r e l a t i o n s ? ” / a n n a b u s s u , c l a u d i o d e t o t t o , “ t h e b i - d i r e c t i o n a l r e l a t i o n s h i p b e t w e e n g a m b l i n g a n d a d d i c t i v e s u b s t a n c e s ” / a l e s s a n d r o f i o r i , t a d a s g u d a i t i s , “ o p t i m a l i n d i v i d u a l c h o i c e o f c o n t r i b u t i o n t o s e c o n d p i l l a r p e n s i o n s y s t e m i n l i t h u a n i a ” / o l i v i e r o a . c a r b o n i , p a o l o r u s s u , m e a s u r i n g e n v i r o n m e n t a l a n d e c o n o m i c e f f i c i e n c y i n i t a l y : a n a p p l i c a t i o n o f t h e m a l m q u i s t - d e a a n d g r e y f o r e c a s t i n g m o d e l / l u c a d e i d d a , j o s é j . c a o - a l v i r a , “ f i n a n c i a l l i b e r a l i z a t i o n a n d t h e d e v e l o p m e n t o f m i c r o c r e d i t ” / m a n u e l a d e i d d a , “ e c o n o m i c h a r d s h i p , h o u s i n g c o s t b u r d e n a n d t e n u r e s t a t u s : e v i d e n c e f r o m e u - s i l c ” / v a n i a m a n u e l a l i c i o , a n n a m a r i a p i n n a , “ m e a s u r i n g i n s u l a r i t y a s a s t a t e o f n a t u r e . i s t h e r e a c a s e o f b a d g e o g r a p h y ? ” / v a n i a m a n u e l a l i c i o , a n n a m a r i a p i n n a , “ t h e e u r o p e a n f i r m s ' e x p o r t a c t i v i t y t o t h e n e i g h b o u r i n g c o u n t r i e s ” / k a l l i o r a s d i m i t r i s , a n n a m a r i a p i n n a , “ t r a d e a c t i v i t y b e t w e e n t h e e u a n d i t s n e i g h b o r i n g c o u n t r i e s : t r e n d s a n d p o t e n t i a l ” / c l a u d i a c i g a g n a , g i o v a n n i s u l i s , “ o n t h e p o t e n t i a l i n t e r a c t i o n b e t w e e n l a b o u r m a r k e t i n s t i t u t i o n s a n d i m m i g r a t i o n p o l i c i e s ” / r o m a n a g a r g a n o , e d o a r d o o t r a n t o , “ f i n a n c i a l c l u s t e r i n g i n p r e s e n c e o f d o m i n a n t m a r k e t s ” / e t t o r e p a n e t t i , “ f i n a n c i a l l i b e r a l i z a t i o n w i t h h i d d e n t r a d e s ” / a d r i a n a d i l i b e r t o , “ l e n g t h o f s t a y i n t h e h o s t c o u n t r y a n d e d u c a t i o n a l a c h i e v e m e n t o f i m m i g r a n t s t u d e n t s : t h e i t a l i a n c a s e ” / a u d r i u s b i t i n a s , a l e s s a n d r o f i o r i m a c c i o n i “ l i t h u a n i a n p e n s i o n s y s t e m ’ s r e f o r m s f o l l o w i n g d e m o g r a p h i c a n d s o c i a l t r a n s i t i o n s ” / g u i l l e r m o b a q u e r o , malika hamadi, andréas heinen “ c o m p e t i t i o n , l o a n r a t e s a n d i n f o r m a t i o n d i s p e r s i o n i n m i c r o c r e d i t m a r k e t s ” www.crenos.it copertina - meloni_paolini_tena_crenos wp contributi - - ( ) - .fm j appl biol chem ( ) ( ), − https://doi.org/ . /jabc. . online issn - print issn - article: bioactive materials beauty food activities of extracts from pinus densiflora root eun-ho lee · ki-tae park · hye-jin park · jae-bum jo · jae-eun lee · su-bin lim · ye-jin kim · dong-hyun ahn · young-je cho 동송근(pinus densiflora root) 추출물의 미용식품활성 이은호 ·박기태 ·박혜진 ·조재범 ·이재은 ·임수빈 ·김예진 · 안동현 ·조영제 received: march / accepted: march / published online: june © the korean society for applied biological chemistry abstract the extracted phenolic compounds from pinus densiflora root were examined biological activities for beauty food. the tyrosinase inhibitory activity which was related to skin-whitening was observed. the tyrosinase inhibitory activity was confirmed to be % in ethanol extract at µg/ml phenolic. the elastase and collagenase inhibitory activity as anti-wrinkle effect were showed and % in ethanol extract at µg/ml phenolic, respectively. astringent effect of ethanol extract was showed to be % at µg/ml phenolic. hyaluronidase inhibitory activity of ethanol extract as anti-inflammation effect was confirmed to be % of inhibition at µg/ml phenolic. these results demonstrated that isolated phenolic compounds from p. densiflora root could be expected to use as a functional cosmetic materials. keywords activity · beauty food · extracts · pinus densiflora root 서 론 오늘날 외모는 현대인들에게 있어서 개인이 가지고 있는 이미 지를 대표하는 중요한 요소이기 때문에 피부 관리에 대한 일반 인의 관심도가 높아지고 있다(kim과 yoo ; lee 등, ). 최근에는 여성뿐 만 아니라 남성들에게도 피부 관리가 중요시 되고 있으며, 관리방법도 기본적인 화장품 사용을 비롯해 기능 성화장품, 팩이나 마사지를 통한 관리, 피부과에서의 전문적인 시술 등으로 다양화 되고 있다(kim과 park ). 피부는 조직 학적으로 표피, 진피, 피하지방의 층으로 구성되어 있는데, 표 피는 이 중 가장 외부에 존재함으로써 피부 노화의 측면에서 가장 중요한 역할을 하며 이에 따라 피부 미용 분야에서도 가 장 집중적인 연구의 대상이 되고 있다(rotts ). 표피는 연 령, 성별, 지엽적 부위, 지속적인 환경자극, 스트레스의 증가 등 의 외부자극 누적으로 인해 그 기능이나 구조에도 변화를 일으 키게 되며, 이러한 변화를 통해서 피부염증, 노화 등의 반응이 진행되고 피부 보호막으로서의 기능이 저하된다(elias ; feingold ). 여기에서 말하는 각질층은 피부의 수분을 보호 하고, 전해질의 소실을 억제하는 장벽의 역할로 인해 표피의 건 조를 막고, 표피가 정상적으로 체내의 생화학적 대사를 할 수 있는 환경을 제공한다. 그리고 외부의 물리적, 화학적 손상으로 부터 인체를 보호하고, bacteria, fungi, virus 등이 피부로 침범 하는 것을 방지하는 역할을 한다(lee 등, ). 피부 표면은 자외선 노출과 같은 산화적 스트레스로 인해 활성산소가 과잉 생성된다. 특히 활성 산소종 중 o −, oh는 피부 노화에 있어 서 매우 중요한 영향을 미치는데, 이러한 활성 산소는 피부 항 산화제 파괴, 피부 단백질의 산화, dna 산화를 일으키고, 결합 조직 성분인 콜라겐, 히아루론산 등의 사슬 절단 및 비정상적 인 교차결합에 의한 염증, 주름, 멜라닌 생성 과정, 등에 참여 하여 피부 노화를 가속화시킨다(joung ). 이에 건강에 대한 young-je cho (�) e-mail: yjcho@knu.ac.kr school of food science & biotechnology/food & bio-industry research institute, kyungpook national university, university street, bukgu, daegu , republic of korea school of culinary art and baking technology, dongju college university, busan , republic of korea department of food science and technology, pukyong national university, busan , republic of korea this is an open access article distributed under the terms of the creative commons attribution non-commercial license (http://creativecommons. org/licenses/by-nc/ . /) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. http://crossmark.crossref.org/dialog/?doi= . /jabc. . &domain=pdf&date_stamp= - - http://orcid.org/ - - - http://orcid.org/ - - - j appl biol chem ( ) ( ), − 관심이 높아지면서 피부를 유지, 관리하기 위한 화장품의 연구 가 활발히 이루어지고 있으며, 특히 식물계에 널리 분포되어 있 는 각종 생약과 식용식물로부터 추출한 페놀화합물은 안전하고 항산화 효과가 뛰어나서 천연 항산화제의 중요성이 부각되어 개 발 및 연구가 활발히 진행되고 있다(halliwell과 gutteridge ; ramarathnam 등, ). 침엽수의 대표적인 소나무(pinus densiflora sieb. et zucc.)는 소나무과(pinaceae)에 속하는 상록교목으로 한국, 일본, 만주 등 에 자생하고 있으며, 국내 어느 지역에서나 널리 자라고 있는 사철 푸른나무이다(oh 등, a; b). 예로부터 소나무의 잎, 솔 방울, 꽃가루, 송진, 껍질, 뿌리 등 모든 부위가 구황식물로 이 용되었으며(lim 등, ), 솔잎의 성분으로는 α-oinine, β- pinene, camphene 등의 정유성분, ercetin, kaempferol 등의 flavonoid류, 수지 등이 함유되어 있다. 쉽게 채취할 수 있는 솔 잎은 민간요법 또는 한방에서 체내조직에서의 산화, 피부질환, 중풍을 예방하고(boo 등, ), 간장질환, 위장질환, 신경계 질 환 등에 대한 효과와 동맥경화증, 고혈압, 당뇨병과 같은 노화 관련 질환을 예방하는 효능이 있는 것으로 알려져 있으며(lee 등, ; kim 등, ; oh 등, ), 소나무 뿌리(동송근) 에 대한 건강기능식품 생리활성 연구 등이 보고되어 있다(lee 등, ). 따라서 본 연구에서는 소나무 뿌리(동송근)로부터 phenolic compounds를 추출하여 미백, 주름개선, 수렴효과 및 항염증 등 의 미용식품활성에 대한 기능성을 검정하고, 기능성 소재로의 활용가능성을 알아보고자 하였다. 재료 및 방법 실험재료 본 연구에서 사용된 동송근은 시중 한약재상에서 판매하는 건 조품을 년에 구입하여 mesh로 분쇄한 후 oc에서 냉장 보관하면서 시료로 사용하였다. 동송근 추출물의 제조 미용식품활성 측정을 위한 시료 추출은 전보(lee 등, )에 서 밝힌 바와 같이 water, ethanol 추출물 모두 건조된 동송근 분말 g을 증류수 ml와 % ethanol ml에 각각 첨 가하여 시간 동안 shaking incubator에서 교반 추출하였다. 각 추출물은 whatman no. filter paper (whatman inc, piscataway, nj, usa)로 여과한 후 필요에 따라 rotary vacuum evaporator (eyela ne, tokyo, japan)에서 농축하여 시료로 사용하였다. total phenolic 정량 total phenolic 정량은 추출물 ml에 % ethanol ml와 증 류수 ml를 첨가하고 n folin-ciocalteu reagent . ml를 잘 섞어 분간 방치한 후 na co ml를 가하여 흡광도 nm에서 시간 이내에 측정하여 gallic acid를 이용한 표준곡선 으로부터 양을 환산하였다(folin과 denis ). tyrosinase 저해효과 측정 tyrosinase 저해효과 측정은 vincent와 hearing의 방법( )에 준하여 측정하였다. 반응구는 . m sodium phosphate buffer (ph . ) . ml와 . mm l-tyrosine 기질 . ml, mushroom tyrosinase (sigma-aldrich co., louis, mo, usa, u/ml) . ml와 시료 . ml를 넣고 대조구에는 시료 대신 증류수를 . ml를 첨가하여 oc에서 분간 반응시켜 흡광도 nm 에서 측정하였다. 저해율(%)은 ( −시료의 absorbance/대조구의 absorbance)× 으로 계산하였다. elastase, collagenase 저해효과 측정 elastase 저해효과 측정은 kraunsoe 등의 방법( )에 준하여 측정하였다. 반응구는 . m tris-hcl buffer (ph . ) ml에 . mm n-succinyl-(ala) -ρ-nitroanilide 기질 . ml, . u/ml porcine pancreatice elastase (sigma-aldrich co.) 효소 . ml와 시료 . ml를 넣고 대조구에는 시료 대신 증류수 . ml를 첨가하여 oc에서 분간 반응시켜 ρ-nitroaniline 생성 량을 흡광도 nm에서 측정하였다. collagenase 저해효과 측 정은 wunsch와 heidrich의 방법( )에 준하여 측정하였다. 반 응구는 . m tris-hcl buffer (ph . )에 mm cacl 를 첨 가하여, -phenylazobenzyl oxycarbonyl-pro-leu-gly-pro-d-arg ( . mg/ml)를 녹인 기질 . ml 및 시료 . ml의 혼합액에 . mg/ml collagenase (sigma-aldrich co.) . ml를 첨가하 였으며, 대조구에는 시료 대신 증류수 . ml을 첨가하여 실온 에서 분간 방치한 후 % citric acid . ml를 넣어 반응을 정지 시킨 후, ethyl acetate ml을 첨가하여 nm에서 흡광 도를 측정하였다. 저해율(%)은 ( −시료의 absorbance/대조구의 absorbance)× 으로 계산하였다. 수렴 효과 측정 astringent 활성은 lee 등의 방법( )에 준하여 측정하였다. 피부 단백질과 유사한 혈액 단백질(hemoglobin)을 사용하여, 원 심분리 용기에 각각의 시료와 헤모글로빈 용액을 : 로 넣어서 진탕 혼합한 다음 , rpm에서 원심분리 후 nm에서 흡광 도를 측정하였다. 대조구는 시료 대신 증류수를 넣어 반응시켰 다. 저해율(%)은 ( −시료의 absorbance/대조구의 absorbance)× 으로 계산하였다. hyaluronidase (haase) 저해효과 측정 hyaluronidase (haase) 저해효과 측정은 dorfman와 ott의 방법 ( )에 준하여 측정하였다. 반응구는 시료 . ml에 mm sodium phosphate buffer (ph . )에 녹인 haase ( , u/ ml) . ml을 혼합하여 oc에서 분간 반응시키고 . m phosphate buffer (ph . )에 녹인 기질 ( mg/ml) . ml을 넣어 다시 oc에서 분간 반응시킨 후 . m acetate buffer (ph . )에 녹인 알부민용액 ml을 첨가한 후 분간 방치하 고 nm에서 투과율을 측정하였다. 대조구는 시료 대신 증류 수 . ml를 넣어 반응시켰다. 저해율(%)은 ( −시료의 투과율/ 대조구의 투과율)× 으로 계산하였다. 통계처리 모든 실험은 회 이상 반복 측정하였고 자료의 통계처리는 spss for windows (statistical package for social science, chicago, il, usa)를 이용하여 평균 ± 표준편차 (mean ± standard j appl biol chem ( ) ( ), − deviation)로 표시하였고 분산분석 duncan’s multiple range test one-way anova를 실시하여 시료간의 유의차를 p < . 수준 으로 비교 분석하였다. 결과 및 고찰 동송근 추출물의 tyrosinase 저해효과 tyrosinase는 l-tyrosine과 페놀류를 산소에 의한 산화반응을 촉 매하는 효소로서, l-tyrosine에 작용해 , -dihydroxyp-henylalanine 이 되고 이를 거쳐 l-dopaquinone으로 전환되어 melanin 형성 에 관여하는 최종단계의 반응을 촉진하는 key enzyme으로 작 용한다. tyrosinase는 최종 melanin 생합성 과정의 중요한 역할 을 하는 enzyme이므로 tyrosinase 억제제는 피부의 melanin 색 소생성을 조절할 수 있는 물질로 사용할 수 있다(laskin과 piccinini ). 본 실험에서는 melanin 형성에 관여하는 enzyme인 tyrosinase를 이용하여 저해효과를 측정한 결과 fig. 에서와 같이 동송근 water 추출물 - μg/ml phenolics 농 도에서 . - . %의 tyrosinase 저해효과를 나타내었으며, . μg/ml의 ec 값을 나타내었다. ethanol 추출물에서는 - μg/ml phenolics의 농도에서 . - . %로 매우 높은 저해효과와 . μg/ml의 ec 값을 나타내었다. 대조구로 사 용된 kojic acid는 . - . %의 저해효과를 나타내었으며, kim 등( )이 한약재 추출물을 . mg/ml phenolics 농도로 처리 하여 tyrosinase 저해효과를 측정한 결과 %의 저해효과를 나 타낸 것과 비교하였을 때 동송근 추출물이 미백제로 시판 중인 kojic acid보다 더 높은 tyrosinase 저해효과를 나타내는 것을 확 인할 수 있었다. 따라서 미백제와 같이 mushroom tyrosinase에 직접적인 저해효과가 있는 미백 화장료로 활용될 수 있다고 판 단되었다. 동송근 추출물의 elastase, collagenase 저해효과 elastin은 진피 내 피부 탄력을 유지하는데 중요한 기질 단백질 이며, elastase는 elastin을 분해하는 효소이다. 체내의 elastin을 분해하는 백혈구 과립 enzyme 중의 하나로, 이상 조직에서는 elastase의 활성이 매우 높아져 피부 주름을 유발하고 탄력성 손 실을 일으키게 된다(dewitt 등, ). 그러므로 피부개선제로 서 ursolic acid, epigallocatechin gallate (egcg) 등의 elastase 저해제는 피부 주름을 완화하는 작용을 나타낸다. 이러한 피부 주름 생성과 관련된 enzyme인 elastase 저해효과를 측정한 결과 fig. -a에서와 같이 동송근 water 추출물에서는 elastase에 대 한 저해효과가 나타나지 않았으며, ethanol 추출물 - μg/ ml phenolic 농도에서 . - . %의 elastase 저해효과와 . μg/ml의 ec 값을 나타내었다. kwak 등( )은 약용 식물로 elastase 저해효과를 측정한 결과 대부분의 약용식물 추 출물 . mg/ml 농도에서 % 미만의 미미한 저해효과를 나 타내었으며, kim 등( )은 한약재 복합 추출물 . mg/ml 농도에서 % 이상의 저해 활성을 나타내었다고 보고하여 동 송근 ethanol 추출물의 저해효과가 우수한 것을 알 수 있었다. 녹차에 함유된 polyphenol의 일종으로 시중화장품에 주름억제를 위한 agent로 사용되는 것으로 알려진 egcg와 동송근 ethanol 추출물의 elastase 저해효과를 비교 하였을 때 동송근 추출물이 fig. inhibitory activity of water and ethanol extracts from p. densiflora root on tyrosinase. means with different superscript letters are significantly different at p < . by duncan’s multiple range tests fig. inhibitory activity of water and ethanol extracts from p. densiflora root on elastase (a), collagenase (b). water extract has not shown activity on elastase. means with different superscript letters are significantly different at p < . by duncan’s multiple range tests j appl biol chem ( ) ( ), − 상대적으로 다소 낮은 저해효과를 나타내었으나 처리한 phenolic 농도에 따라 농도의존적으로 저해효과가 증가하는 것을 확인할 수 있었으며, 동송근 추출물도 egcg와 같이 elastase 저해효과 가 있다는 것을 확인하였다. 피부의 fibroblast에서 생성되는 collagen은 extracellular matrix의 주요 구성성분으로 견고한 중 나선구조를 가지고 있는 단백질이다. 뼈와 피부의 진피(dermis) 에 높은 함량으로 분포되어 있는 collagen은 피부, 건(tendon), 뼈 및 치아의 유기 물질의 대부분을 형성한다. collagen의 주된 기능으로는 피부의 구조적 견고함, 세포의 접착, 세포 분할과 분화, 결합조직의 저항력과 조직의 결합력을 유도 하는 역할을 담당하고 있다(jeroma 등, ). 이러한 collagen은 자외선에 의한 광노화에 의해서 감소하게 되며, 또한 단백질 분해효소인 collagenase에 의해 분해되어 피부의 구조적 견고함을 유지하고 있는 다발성 나선구조를 무너뜨려 주름을 발생시킨다(grant과 alburn ; demina과 lysenko ). collagen을 분해하는 enzyme인 collagenase를 이용하여 저해효과를 측정한 결과 fig. b에서와 같이 동송근 water 추출물 - μg/ml phenolics 농도에서 . - . %의 저해효과를 나타내었으며, ec 값의 경 우 . μg/ml로 확인되었다. ethanol 추출물에서는 . - . %의 저해효과를 나타내었고, . μg/ml의 ec 값을 나 타내어 추출물 모두 농도의존적으로 collagenase 저해효과가 증 가하는 양상을 보여주었다. lee 등( )은 유백피 추출물로 collagenase 저해효과를 측정한 결과 ppm에서 . %의 저 해효과를 나타내었으며, barrantes과 guinea( )의 알로에 추 출물 경우 . %를 나타내었다고 보고한 것과 비교하였을 때 동송근 추출물의 효과가 매우 우수한 것으로 판단되었다. 따라 서 동송근 추출물은 피부 탄력을 유지하는데 중요한 단백질인 elastin과 collagen을 분해하여 주름 유발에 영향을 미치는 enzyme인 elastase, collagenase를 억제하여 피부 주름개선 효과 에 긍정적인 효과를 미치는 것으로 확인되었다. 동송근 추출물의 수렴 효과 수렴작용(astringent)은 동물의 근육에 구성되어 있는 단백질인 myosin, actin, myoglobin과 혈액에 존재하는 색소 단백질인 hemoglobin과 같은 피부 단백질이 고분자 phenolic compounds 와 가교결합을 형성하게 되어 피부가 수축되는 현상을 말한다. 이러한 수렴작용은 피부와 점막의 표면에 난용성의 피막을 형 성하거나 피부조직을 조밀하게 하여 세포막으로의 투과성을 감 소시키는 역할을 한다(tsuji ). 피부 단백질인 hemoglobin 을 이용하여 수렴 효과를 측정한 결과 fig. 에서와 같이 water 추출물에서는 . - . %로 다소 낮은 수렴 효과와 . μg/ ml의 ec 값을 나타내었으며, ethanol 추출물에서는 μg/ml phenolic 농도의 저농도에서도 . %와 . μg/ml의 ec 값으로 높은 수렴 효과를 나타내어 positive control로 사용한 tannic acid의 수렴 효과인 . - . %에 비해 매우 우수한 효 과를 나타내었다. 이는 lee 등( )의 함초 추출물이 % ethanol 및 acetone 추출물에서 %의 수렴 효과를 나타내었다 고 보고한 것과 비교하였을 때 동송근 ethanol 추출물의 수렴 효과가 우수하다는 것을 확인할 수 있었고, 피부 단백질인 hemoglobin을 수축하여 수렴작용에 효과가 있다고 판단되어 모 공 축소효과를 활용한 기능성 화장품 원료로써 활용 가능성이 기대되었다. 동송근 추출물의 hyaluronidase (haase) 저해효과 염증반응은 자외선과 같은 외부자극에 의해서 일어나는 생체조 직의 방어반응의 한 종류로서 활성화된 면역세포에 의해 일어 나는 일련의 면역반응이다. epidermis와 dermis에 있어서 주요 한 세포외 metrix인 hyaluronic acid (ha)는 glucuronic acid와 glucosamine이 반복해서 연결된 고분자의 점액성 mucopoly- saccharide이다. 고분자 ha는 염증 형성의 중요 요소인 macrophage의 phagocytic ability를 저해시키지만, 저분자 ha는 inflammation, fibrosism collagen deposition을 증가시킨다고 알 려져 있다. 따라서 ha 분해효소인 haase의 활성을 억제함으 로서 ha의 고분자 형태를 유지시켜 항염증 효과를 기대할 수 있다(ghosh ; cho과 an ). 염증 형성의 중요 요소인 haase 저해효과를 측정한 결과 fig. 에서와 같이 water 추출 물에서는 - μg/ml phenolic 농도에서 . - . %의 저해효 과를 나타내었으며, ec 값은 . μg/ml으로 나타내었다. fig. astringent effect of water and ethanol extracts from p. densiflora root. means with different superscript letters are significantly different at p < . by duncan’s multiple range tests fig. inhibitory activity of water and ethanol extracts from p. densiflora root on hyaluronidase. means with different superscript letters are significantly different at p < . by duncan’s multiple range tests j appl biol chem ( ) ( ), − ethanol 추출물에서는 - μg/ml phenolic 농도에서 . - . %의 저해효과와 . μg/ml의 ec 값을 나타내어 - μg/ml의 고농도에서는 매우 높은 haase 저해효과를 보여 주었다. cho( )와 cho( )가 보고한 숙지황 ethanol 추출 물과 미세분쇄 감국 ethanol 추출물에서 각각 . , . %의 저 해효과를 나타내었다고 보고한 것과 비교하였을 때 동송근 ethanol 추출물의 haase 저해효과가 우수하다는 것을 확인할 수 있었으며, 염증 유발 요소인 haase 저해로 인한 항염증, 아토 피 억제효과를 활용하는 제품에 적용할 수 있을 것이라 판단되 었다. 초 록 소나무 뿌리(동송근)로부터 phenolic compounds를 추출 후 미 용식품활성을 검정하여 기능성 소재로 활용가능성을 살펴보았 다. 동송근에 함유된 페놀성 물질의 tyrosinase 저해효과를 측정 한 결과 μg/ml phenolics 농도에서 ethanol 추출물이 % 의 tyrosinase 저해효과를 나타내었다. elastase와 collagenase 저 해효과를 측정한 결과 μg/ml phenolics 농도에서 ethanol 추출물이 각각 , %의 높은 저해력을 나타내어 주름개선효 과가 높았다. 수렴효과는 μg/ml phenolics의 저농도 ethanol 추출물에서 %의 저해효과를 나타내었다. 염증억제효과를 나 타내는 hyaluronidase 저해효과를 측정한 결과 - μg/ml phenolic 농도의 ethanol 추출물에서 - %의 매우 높은 염증 억제효과를 나타내었다. 이러한 결과로 보아 동송근 추출물이 미용식품활성 또는 기능성 소재로서 활용이 가능할 것으로 판 단되었다. keywords 동송근·미용식품·추출물·활성 references barrantes e, guinea m ( ) inhibition of collagenase and metallo- proteinases by aloins and aloe gel. life sci : − boo yc, jean co, oh jy ( ) isolation of -hydroxy- -methyl- [ h]- furanone from pine needles as an antioxidative principle. j korean soc agric chem biotechnol : − cho yj ( ) charactrization of biological activities of rehmannia glutinosa extracts. journal of life science : − cho yj ( ) biological activity of extracts from chrysanthemum incidicum linne by ultrafine grinding. j korean soc food sci nutr : − cho yj, an bj ( ) anti-inflammatory effect of extracts from cheongmoknosang (morus alba l.) in lipopolysaccharide stimulated raw cells. j kor soc appl biol chem : − demina ns, lysenko sv ( ) collagenolytic enzymes synthesized by microorganisms. mikrobiologiia : − dewitt dl, rollins te, day js, gauger ja, smith wl ( ) orientation of the 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related to its massless dirac-like bandstructure. in addition, graphene inspired deep insights into the phases of matter. it was in the context of graphene that the quantum spin-hall effect was first thought of [ ], an insight which flourished into the field now known as topological insulators. as it turns out, the spin-orbit interaction is quite weak in graphene so that its spin-hall effect remains inaccessible to experiment. this provides but one motivation for pursuing alternative graphene-like systems which promise access to new parameter regimes. an elegant approach to realize artificial graphene was recently taken by h.c. manoharan and collaborators. their experiment exploits that scanning tunneling microscopes allow for manipulating atoms or molecules adsorbed on metallic surfaces with atomic precision. this is used to arrange co molecules into a hexagonal lattice on a cu ( ) surface which is known to have a band of surface states. the co molecules impose a periodic potential on the surface electrons, resulting in a graphene-like bandstructure. when the lattice spacing is chosen on a nanometer scale, comparable to the fermi wavelength of the surface electrons, this artificial-graphene system has its fermi energy close to the dirac point. the lattices created in this experiment, consisting of hundreds of co molecules, could then be probed by scanning tunneling spectroscopy. the differential tunneling conductance provides a good measure of the local density of states as a function of energy. by measuring the tunneling conductance near the center of such a lattice, the authors confirmed the approximately linear dependence of the density of states on energy expected for a dirac cone. the local nature of scanning tunneling spectroscopy allows for probing the two (a and b) sublattices separately and hence to address the pseudospin degree of freedom of the corresponding dirac equation. the authors exploited this to extract the massless dirac spectrum directly from experiment. even with the constraints of the registry with the underlying cu surface, the co lattice can be realized with different lattice spacings. this was used to realize pn-junctions which were sharp on the scale of one lattice spacing. one way to think about the shift of the dirac point with lattice spacing is as a consequence of the familiar (scalar) deformation potential associated with a lattice distortion. more general lattice distortions generate not only scalar but also vector potentials in the dirac equation. the authors explored these as well by creating local defects in the honeycomb lattice, both pseudospin conserving and pseudospin breaking, and measuring the distinct differences in the rotational symmetry of the local density of states around the defect. perhaps the most striking illustration of the opportunities afforded by artificial graphene is provided by two large-scale lattice distortions. in one experiment, the authors added additional co molecules within the hexagons in a ‘mercedes’ arrangement. within a tight-binding picture, this modulates the hopping amplitudes between neighboring sites in an alternating fashion, known as a kekule pattern. this endows the dirac fermions with a mass, and indeed the authors observe that the local density of states now develops a gap. in another experiment, the co molecules form a hexagonal lattice distorted in such a way that the strain-induced vector potential corresponds to a uniform magnetic field acting on the dirac fermions (albeit with opposite signs in the two valleys to preserve time reversal symmetry). the magnetic field with strengths reaching tesla causes the formation of a zeroth landau level, a hallmark of dirac physics. the sublattice asymmetry of the zeroth landau level leads to the development of a zero-bias peak when measuring the differential tunneling conductance on one sublattice and to the development of a landau gap when measuring on the other. this experiment complements a number of approaches to realize artificial graphene (see ref. [ ] for a recent review). the major driving force behind this research is the flexibility to tune parameters in these systems which promises access to correlated or topological phases which are inaccessible in natural graphene. the setting of the present experiment may not be particularly conducive for the realization of many- body effects since the electron-electron interaction is strongly screened by the bulk electrons of the cu substrate. prospects for the realization of topological phases could be considerably more favorable, e.g., by employing substrates with stronger spin-orbit coupling. [ ] c. l. kane and e. j. mele, phys. rev. lett. , ( ) [ ] m. polini, f. guinea, m. lewenstein, h. c. manoharan, v. pellegrini , artificial graphene as a tunable dirac material, arxiv: . . the beautiful risk of education (gert biesta) copyright ©, doron yosef-hassidim this document is protected by copyright law. use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ this article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the université de montréal, université laval, and the université du québec à montréal. its mission is to promote and disseminate research. https://www.erudit.org/en/ document generated on / / : p.m. philosophical inquiry in education the beautiful risk of education (gert biesta) doron yosef-hassidim volume , number , uri: https://id.erudit.org/iderudit/ ar doi: https://doi.org/ . / ar see table of contents publisher(s) canadian philosophy of education society issn - (digital) explore this journal cite this review yosef-hassidim, d. ( ). review of [the beautiful risk of education (gert biesta)]. philosophical inquiry in education, ( ), – . https://doi.org/ . / ar https://apropos.erudit.org/en/users/policy-on-use/ https://www.erudit.org/en/ https://www.erudit.org/en/ https://www.erudit.org/en/journals/pie/ https://id.erudit.org/iderudit/ ar https://doi.org/ . / ar https://www.erudit.org/en/journals/pie/ -v -n -pie / https://www.erudit.org/en/journals/pie/ p h i l o s o p h i c a l i n q u i r y i n e d u c a t i o n , volume ( ), no. , pp. - review of the beautiful risk of education by gert j.j. biesta, boulder: paradigm publishers, doron yosef-hassidim university of toronto biesta’s work in last two decades is of the kind that is too often lacking in philosophy of education discourses, or in foundations of education in general: examination that takes education itself, as a whole, as its “unit of analysis,” and focuses on what education should mean. the beautiful risk of education continues biesta’s efforts to articulate what in hindsight he refers to as a “theory of education” (p. xi), a theory not only in the descriptive sense but primarily in the normative one. this book is the latter in what can be seen as a series of three books by gert biesta. in beyond learning: democratic education for a human future ( ) he develops subjectivity as a central dimension in education through a critique of the dominant discourse of learning in education and an exploration of the notion of “coming into presence.” in good education in an age of measurement ( ) he introduces a broader education framework by adding two other dimensions, qualification and socialization. in the beautiful risk of education ( ) biesta “focuses on a theme that was implicit in the other two books” (p. x), namely the weakness of education. biesta believes this theme deserves explicit examination since it has important implications that might assist in engaging with his ideas in practical settings. this review is a good opportunity to take a comprehensive look at biesta’s work, after completing the ‘trilogy’. biesta draws on philosophical texts from a broad range of areas, including ethics, politics, and theology, while at the same time he does not lose sight of his main interest: what is educationally desirable. this is a challenging attempt to combine two allegedly contradictory scholarly approaches: one that rests on other domains and another that seeks to define its own way. indeed, as can be seen by reading this book in the context of biesta’s corpus, he faces the challenge by honestly engaging with both approaches in a search for a richer way of thinking about education. in the beautiful risk of education biesta characterizes and argues against “strong” perceptions and practices of education, and explains and exemplifies a “weak” view through seven “themes”: creativity, communication, teaching, learning, emancipation, democracy, and what biesta labels ”virtuosity”. he defines his idea of ”weak education” against current dominant perceptions of education and a “desire to make education strong, secure, predictable, and risk-free” (p. ). ”strong” education is associated with ”effective production of pre-defined ‘learning outcomes’” and with ”a limited set of identities” (ibid.). biesta argues that this perception of education is a “fundamental misunderstanding of what education is about” (p. ) since education ”isn't a mechanism and shouldn't be turned into one” (p. ). actually, the educational way is ”the slow way, the difficult way, the frustrating way, and, so we might say, the weak way, as the outcome of this philosophical inquiry in education process can neither be guaranteed nor secured” (p. ). the risk in education stems from the view that education is “not only interested in qualification and socialization but also in subjectification, that is, in the possibility of the event of subjectivity” (p. ). for biesta, following levinas, subjectivity is not a quality one possesses, and therefore “subjectivity is not understood as an essence but as an event” (p. ). events of subjectification occur ”when individuals resist existing identities and identity-positions and speak on their own terms” (p. ). since the event of subjectification “may or may not happen” (p. ), there is a risk in education, and “[t]o engage with the openness and unpredictability of education… means to take this risk seriously, and to do so not because the risk is deemed to be inevitable… but because without the risk, education itself disappears and social reproduction, insertion into existing orders of being, doing, and thinking, takes over” (ibid.). missing the protective potential in arendt’s view as part of his discussion of democracy biesta evaluates arendt’s understanding of politics—and as such her call to separate education from politics—through the lens of rancière’s work. biesta argues: “if rancière helps us to see how education and politics are intimately connected if what is ‘at stake’ is the question of emancipation, hannah arendt… is an author who comes from the opposite end, as she has been one of the most outspoken critics of the idea that education and politics may have anything to do with each other” (p. ). since biesta adopts rancière’s ideas about equality, democracy, and politics in his discussion of emancipation, it seems that when arendt challenges the place of politics in education, biesta has the same meaning of politics in mind as rancière’s, that is, human existence within conditions of plurality. biesta argues that arendt’s argument is based on the assumption of psychological developmentalism. quoting arendt, he writes that it is “a particular view of childhood (and hence of adulthood) in which the child is seen as ‘a developing human being’ and childhood is seen as ‘a temporary stage, a preparation for adulthood’” (p. - ). biesta argues that this view signifies “a fundamental distinction between children and adults” (p. ). thus, biesta arrives at—and rejects—a stand that refuses to let children and students deal with the political realm. once developmentalism is rejected, he argues, we have to accept “the intimate connection between education and democratic politics” (p. ). however, this connection is established not by preparing for political existence but by experimenting it, since “political existence can never be guaranteed but always has to be reinvented” (p. ). therefore, biesta concludes, “freedom cannot be produced educationally but can only be achieved politically” (p. ). i find biesta’s argument against arendt valid. however, since biesta seeks a fundamental perceptual change about education, he needs to not only to offer an alternative but also to target obstacles to realizing this alternative; rejecting arendt’s view on education in relation to politics misses an opportunity to do so. we have to bear in mind unwelcomed political and economic interventions in education that attempt to influence what is educationally desirable. these interventions are aggressive and uncompromising to the extent that what education actually means—and consequently its role and place in society—is dictated by self-interested forces that demand “strong” and mechanistic “education”. being aware of such interventions, we should not just develop alternative conceptual frameworks for education; perhaps even more importantly, we should consider how to protect education from exploitive intrusions. therefore, we should seriously examine philosophical calls to “isolate” education from other realms, especially those realms that seek a footing in education in pursuit of their own interests. such philosophical calls might be fraught with underexamined doron yosef-hassidim ideas that carry the potential to shield education (not in the sense of making it “strong”). arendt’s ( ) observation that “education became an instrument of politics” (p. ) and her plea to “decisively divorce the realm of education from the others, most of all from the realm of public, political life” (p. ) is such a call that deserves our careful attention. perhaps the separatist tone in arendt’s work is not thoroughly founded or not motivated enough—it appears as part of a relatively short essay (“the crisis in education“) and not as part of a comprehensive program for education or a general social framework—but it is courageous and thought-provoking, and not every adaptation of it means “to declare the school a ‘no-go area’ for political existence” (p. ), as biesta worries. to be sure, biesta is well aware of the fierce political struggle around education. he criticizes the “very functionalist view of education,” a view that “paints a picture where society—and there is of course always the question who ‘society’ actually ‘is’—sets the agenda, and where education is seen as an instrument for the delivery of this agenda,” and that “thinks of the school as the institution that needs to solve ‘other people’s problems’” (p. - ). biesta also notes that “governments in many countries have established a strong grip on schools” (p. ), and with regard to understanding education as a causal process of production he states that “in a lot of countries education is rapidly moving in this direction and is becoming oppressive” (p. - ). against this dominant instrumental and oppressive approach to education biesta endorses weak education with an emphasis on subjectification and emancipation facilitated by professional judgment. but biesta does not take the political struggle itself around education as part of his plan for education, or his “theory of education.” in the current situation where education is viewed as a legitimate instrument to gain power and control, as biesta rightly observes, any comprehensive program for education—even if “just” philosophical or theoretical—must not only characterize the threats to education but also inherently confront them and offer ways to fend them off. without a plan for how to overcome threats to education—at least conceptually—a vision or program for education is not just incomplete but also lacks significant practical force, and as such has little chance of being translated into action, even if accepted within educational and political circles. in this sense, arendt’s analysis of the “rise of the social” is something that educationalists should carefully examine with regard to education. for arendt, in late modernity, with the expansion of the market economy, the social has increasingly invaded both the public and private realms, and resulted in “the demise of the political”, as biesta ( , p. ) notes. as i see it, this dominance of the social underlies the interconnected phenomena that biesta articulates in the educational domain such as the pursuit of “strong” education and “what works”, as well as what he labels the “learnification” of educational discourse and practice. biesta mentions the “rise of the social” as an expression of the distortion and reversal of the hierarchy within the vita activa, but he does not explicitly link it to the current situation of education and to the threats to education. as there is a direct link between the “rise of the social” and the dominant perception and practices of education, an alternative view of education must deal with the rise of educationally oppressive social forces. there is one point, however, where biesta does acknowledge a threat to weak education and implicitly suggests a need for protective measures. this appears in the appendix, and i suspect that alongside other explicit statements this is the reason why this interview with biesta was attached to the book. in the appendix biesta admits and warns that “while subjectivity cannot be produced through education—or for that matter politics—it is actually quite easy to prevent the event of subjectivity from occurring… it is quite easy, both at the individual level and at the institutional level, to create situations in which the possibility for being addressed is edited out” (p. ). it is crucial to understand, however, that situations that prevent subjectivity usually do not happen by accident. they are rooted beyond the individual or organizational level and originate philosophical inquiry in education in the overall systemic and social context, in the general political discourse about education and by the dominant instrumental view on the role and place of education in society. and when this view leads to aggressive attempts to penetrate the educational realm in order to influence it, subjectivity becomes so vulnerable and so fragile that the first task is to protect it. we can say, relating to biesta’s discussion of teacher education, his critique of the discourse of “competencies” and his advocacy for practical educational wisdom, that as part of this wisdom educationalists should develop a ‘sense’ to ‘feel’ or ‘detect’ attacks on education (or threats to their professional judgment), and moreover to develop the capacity to keep these attacks away and to protect students and education as a whole. therefore, it is not enough to acknowledge that education is exploited politically as an oppressive instrument and that consequently subjectivity needs to be guarded; it is also crucial to ask questions about who profits from preventing subjectivity and who tries to attack it, and to trace the specific strategies taken by oppressive factors that wish to shut down any alternative view of education. to use biesta’s terminology when he distinguishes between two understandings of creation, the weak existential (“in terms of encounters and events”, p. ) approach to education he offers has to acknowledge and block the prevalent strong metaphysical (“in terms of causes and effect”, p. ) ways education is perceived, not just to present itself as an alternative. looking broadly at biesta’s work vis-à-vis the rise of the social, it seems that biesta’s attempt to juxtapose subjectification with qualification and socialization, as more or less three equal overlapping dimensions or domains in which “educational processes and practices always operate” (p. ix), might erode subjectivity. following the realization that the question of subjectivity—which was addressed in the book beyond learning ( )—“is not the be-all and end-all of education” (p. ), biesta adds in the book good education in an age of measurement ( ) two other dimensions, qualification and socialization. in the beautiful risk of education biesta explains that the domain of qualification “has to do with the ways in which, through education, individuals become qualified to do certain things (this is the domain of the acquisition of knowledge, skills, values, and dispositions)”, and the domain of socialization “has to do with the ways in which, through education, individuals become part of existing social, political, professional, and so on ‘orders’” (p. ). thus, biesta states that “education is never one-dimensional in its intentions and ambitions so that there is always the difficult question of how to strike the right balance” (p. x), that “teachers constantly need to make judgments about how to balance the different dimensions” (p. ), and that the art of teaching “is precisely that of finding the right balance among the three dimensions” (p. ). however, biesta does not address the fact that constant interventions have shifted education so radically towards an interconnected mesh of qualification and socialization—or, perhaps more accurately, qualification in the service of socialization—that any balance that might have existed in the past has been violated. it seems that as a result biesta does not find it necessary to devise protective measures in order to allow teachers the opportunity to restore or create a balance. as suggested above, protecting education means to prevent self- interested forces from prescribing an instrumental sense of education, especially though identifying and blocking exploitive efforts of qualification and socialization. it is important to note that adopting arendt’s view for a vision of education that protects education from the political sphere is not unthinkable. a recent work that explicitly adopts arendt’s call to separate education and politics is by masschelein and simons ( ). in their book in defense of the school: a public issue they argue that in order to truly prevent the school from reproducing social inequality, schools must be a place of suspension from society. as i read them, they reject the dominance of both biesta’s qualification and doron yosef-hassidim socialization dimensions, and, noting that “[p]olicymakers are often tempted to look to the school for solutions to societal problems” (p. ), they stress, as if in response to biesta: we make a clear distinction between school and politics, between educational responsibility and political responsibility, between the renewal made possible by pedagogy and political reform. in one way or another, politics is about negotiation, persuasion or a struggle between different interest groups or social projects. the table at school is not a negotiating table; it is a table that makes study, exercise and training possible. (p. ) educational theory of education? it is useful to examine biesta’s book, and particularly his critique of arendt, through the lens of his work on how education as a field and academic discipline is perceived. his rejection of a separation between education and politics seems at odds with the continental construction of education that he has explored in recent years ( , b) and seems to find worth considering. biesta ( ) explains that the anglo-american construction and the continental construction differ in their answer to “the question of whether there are forms of theory and theorising that are distinctively educational rather than that they are generated through ‘other’ disciplines” (p. ). the english-speaking tradition generally denies a distinct educational theorizing and takes a ‘disciplinary approach’ according to which education is constructed by the contributions of other foundational disciplines. on the other hand, on the continent, particularly in the german-speaking world, a central idea in pädagogik is “the idea of education as a discipline in its own right with its own forms of theory and theorizing” (p. ). according to this approach, biesta explains, “we need a theory of education that is neither psychological, sociological, historical nor philosophical, in order to identify our object of study” (p. ). unlike the academic orientation in the anglo-american construction, for pädagogik there is more than just something to explore in education; there is something to take care of, an ‘asset’ to tend to, to look after: the child. but close examination of biesta’s earlier work reveals a complicated picture that sheds light on the beautiful risk of education. on the one hand, although biesta does not explicitly declare a preference for the continental approach over the anglo-american one in his work, it seems that he sympathizes with the independence implied in the continental construction. for example, he ( ) states with regard to “the relative autonomy of pädagogik” that “[t]he key idea here was that pädagogik had a role to play in protecting the domain of education – and through this, the domain of childhood more generally – from claims from societal powers such as the church, the state or the economy” (p. ). biesta ( b) also says that within the continental construction “we find a situation where education developed as an academic discipline in its own right, on a par with, rather than subordinated to psychology, sociology, history and philosophy” (p. ). this sympathy to the continental approach of treating education as an endeavor with its own autonomy aligns with ideas expressed in the beautiful risk of education that resonate with the continental aspiration for a theory of education that stands on its own legs. for example, he argues that arendt’s notion of freedom—which he embraces—provides us with “a way of understanding democratic education that is nonpsychological and nonmoral but nonetheless thoroughly educational” (p. ). biesta also states that “the particular common sense about education that is being multiplied” by the discourse about competence—which he criticizes—is an “un-educational way of thinking about education” (p. ). later on he says that “we wish to move beyond the language of learning, philosophical inquiry in education we need to engage with a way of speaking and thinking that is more properly educational” (p. ). biesta also talks about the “educational concern” (p. ), “the educational question” (p. ), the “educational thinking” (p. ) and “educational point of view” (p. ). moreover, biesta declares in the appendix that his theory of education “[c]onceptually… hangs on two notions, ‘coming into the world’ and ‘uniqueness’” (p. ), both of which were already developed in beyond learning as educational notions (although with reference to philosophical ideas, for example when biesta criticizes humanism since it “is unable to grasp the uniqueness of each individual human being”, , p. ). biesta states in beyond learning: “the role of the educator… has to be understood in terms of a responsibility for the ‘coming into the world’ of unique, singular beings, and a responsibility for the world as a world of plurality and difference” (p. - ). thus, we can conclude that the theory of education that emerges from biesta’s book (and perhaps his recent work in general) is quite “distinctively educational,” and as such has a continental flavour. on the other hand, however, biesta also integrates a disciplinary approach in the beautiful risk of education as he converses with ‘discussion partners’, as he calls them, from different philosophical areas (see p. with regard to dewey and derrida and p. with regard to arendt. rancière and others can also be considered as biesta’s interlocutors). in particular, his theory of education is closely associated with the notions of politics, democracy, equality, and plurality that are not educational notions in and of themselves; after all, not every discussion about the way human beings live together takes an educational point of view. therefore, it is difficult to say that biesta attempts to develop a theory of education (or that he sees education as an academic discipline) that has theoretical and conceptual power “in its own right” (an expression biesta uses, e.g. , p. ). in this sense, biesta’s firm rejection of arendt’s call to separate education from politics demonstrates his reluctance to allow education such sovereignty over its own business. therefore, it is unclear how to settle biesta’s sympathy toward continental educational autonomy with his tendency to draw on other disciplines; does he just “consult” his “discussion partners”? does he doubt whether genuine educational way of thinking is actually possible? is it biesta’s attempts to advocate for continental construction within the anglo-american community’s approach to philosophy of education that he ( b) is afraid is “a historical mistake”? from this emerging ambivalence, found in the beautiful risk of education, between the anglo-american construction and the continental construction, it seems that this book reflects biesta’s attempt to bring the two constructions into a fruitful conversation with the aim of developing a theory of education—or, as i prefer to see it—an educational way of thinking. as he argues in a paper: “even if the two constructions are to a certain degree incommensurable as there is no common measure that would allow for the simple conversation of the one into the other, i do not see such incommensurability as the end of communication” (p. ). perhaps acknowledging that you cannot have it both ways, and therefore seeking to move beyond these constructions, he adds: “incommensurability rather indicates a situation in which different traditions might become curious about each other, might learn about each other and, through this, might also begin to see their own ways of doing and thinking differently.” (p. ). thus, it is perhaps most appropriate to view this book as biesta’s exploration of how two approaches to education, with their different historical and cultural foundations, can be useful for offering new horizons for education. the last point explains why the beautiful risk of education is recommended to anyone who is looking for a fresh, rich, and responsible foundational conceptualization of education. doron yosef-hassidim references arendt, h. ( ). between past and future: six exercises in political thought. new york: viking press. biesta, g. j. j. ( ). beyond learning: democratic education for a human future. boulder: paradigm publishers. biesta, g. j. j. ( ). good education in an age of measurement: ethics, politics, democracy. boulder: paradigm publishers. biesta, g. j. j. ( ). disciplines and theory in the academic study of education: a comparative analysis of the anglo-american and continental construction of the field. pedagogy, culture & society, ( ), - . biesta, g. j. j. ( b). is philosophy of education a historical mistake? connecting philosophy and education differently. theory and research in education, ( ), – . masschelein, j. & simons, m. ( ). in defense of the school: a public issue. leuven: e-ducation, culture & society publishers. available at http://ppw.kuleuven.be/ecs/les/in-defence-of-the- school/jan-masschelein-maarten-simons-in-defence-of-the.pdf. sam a discussion paper sam issn: - september i n s t i t u t t f o r s a m f u n n s Ø k o n o m i d e p a r t m e n t o f e c o n o m i c s a journey for your beautiful mind: economics graduate study and research by ching-to albert ma this series consists of papers with limited circulation, intended to stimulate discussion. - - a journey for your beautiful mind: economics graduate study and research a lecture to graduate students of the joint economics ph.d. program of the department of economics, university of bergen, and the norwegian school of economics. ching-to albert ma department of economics boston university and university of oslo august , bergen, norway acknowledgement: many friends, colleagues and students inspired me. my thanks to ingela alger, lucia chung, randy ellis, jacob glazer, simona grassi, miriam hatoum, michael hoel, tor iversen, bart lipman, ting liu, tom mcguire, michael manove, debby minehart, dilip mookherjee, claudia olivetti, ariel rubinstein, fred schroyen, kam-wing siu, monic sun, and cecilia wan for their comments on earlier drafts. - - you must be very excited, ready to start your ph.d. program here in bergen. to many of you this will be an important milestone. it should be. undertaking a ph.d. study is not a trivial matter, and i hope that you do take this seriously. i have been asked to address you on matters concerning modern economics and your upcoming study and research. this is a daunting task. first, modern economics is a huge subject. second, graduate study and research in economics is also a huge subject. early on i have come to the conclusion that your professors here have given me a mission impossible, but i’ll try my best in the next hour or so. let me first say that my own research is mainly on applied microeconomic theory. my experience with empirical research is very limited. i probably don’t have many useful things to say about handling data, selecting statistical software, etc. in other words, you are going to listen to some biased views, so beware. . modern economics once upon a time, an economist could stand up and say that economics is about the allocation of resources. i am afraid that that is history. economists by now have done quite a bit more than resource allocations. if you pick up a recent economics journal, you’d see that the titles of the articles can seem rather strange. for example, in recent issues of the journal of economic theory, you’d read titles such as • ambiguous events and maxmin expected utility • subjective probabilities on “small” domains • exploitation and time • p-best response set but these strange titles are not limited to microeconomic theory. look at the journal of monetary economics, and you will find titles such as • do self-control preferences help explain the puzzling behavior of asset prices? • inattentive consumers • big elephants in small ponds: do large traders make financial markets more aggressive? now some working papers are even less revealing. i have come across an economics working paper: “are working women good for marriage?” you’d wonder when economists have started their dating or marriage counseling service. or how about “why we grow large, and then grow old: economics, biology and mortality?” a working paper written by a very senior economist. if these titles are about economics, you must be thinking about a ph.d. thesis on why norwegians sing in their showers! such is the nature of modern economics. the word “price” almost never appears anywhere in the title of an article now. often the word “price” doesn’t even appear - - anywhere in the article. these days economics is much more than price and resource allocation. nor is it only about inflation and employment. economists have been trying to model many issues, some of which were previously the domain of political scientists, sociologists, psychologists, and anthropologists. the keyword is “model,” a technique that is usually associated with abstraction, formalism, and mathematical and statistical techniques. modeling: the economist’s language i am sure that you will model something. above all else, it is this general methodology that you will learn in the next few years. this is what modern economics is all about. i sometimes have the feeling that what makes a paper publishable in an economics journal is not what it is on, but how the analysis is done. it has to be done in a way that can be understood by economists. it can be on obesity, language, fish, global warming, procrastination, ambiguity, regret, the impending dooms-day prediction on the us social security system, or diversity of species. but they all share something in common. they share the same methodology. economists abstract; we simplify, and we analyze. there is a model, some model, which always carries some assumptions. it emphasizes some issues, and deemphasizes others. then there are some auxiliary assumptions. after that, some analysis, be it mathematical or statistical. and then some results, conclusions, lessons learned. you will have to do that, very soon. sometimes economists begin with some institution, some experiments, and then data. we state our hypotheses, the identification method, and then the regression results. or we use some calibration method to gauge how accurate a model fits the data. these are all common methods that economists understand. and you will have to learn them. and that of course brings us to your mind. you see, most young minds are really not accustomed to thinking in terms of economic models. i’d like to illustrate this difficulty with an example amartya sen used. john was lost and looking for the railway station. he came upon david, and asked david for direction. david said, “the station is just behind the post office. you will see it once you go past the post office. and by the way, would you mind putting this letter in the post office box when you go there?” john thanked david for the direction, took the letter, and started walking. but en route, john opened the letter to see if there was anything valuable! almost anyone would be appalled by these behaviors. i am sure that when you are asked for direction, you would not attempt to give an answer to convenience yourself, and when you are asked to mail a letter, you wouldn’t open it to see if there is money inside. most of us would not behave this way. indeed, sen said that someone who behaved exactly as economics predicted would be a social moron; such a person would not be able to - - function in society. but these behaviors are not surprising to economists. in fact, looking for gains in every possible way is exactly what economists aim to derive from their models---otherwise how could there be an equilibrium? let me give you another example. a labor economist was asked what was the most important determinant of employment. he said “wage.” he was then asked what was the second most important determinant of employment. he thought for a second, and answered, “log of wage.” to an ordinary person, perhaps the first answer is quite reasonable. but the second answer? well, most would think about culture, job satisfaction, working hours, etc. log of wage? it takes some courage, right? perhaps it also shows how far abstraction can go. when you were an undergraduate, you were taught how to read economics, understand books, maybe even study some research papers. now that you enter a graduate program, you will be taught how to do economics. so first you have to understand how economists’ minds work. they certainly work in a very peculiar way, abstracting away a lot of things from reality, concentrating on only a few things. it requires a lot of learning and experience to select what are the things you need to discard, and what the things to include in your models. in a nutshell, this is what you are going to do for the next few years, maybe even for your career after the ph.d.: what to keep and what to discard. what is it that your mind has to learn? there is a certain “maximizing” method for modeling economic behavior that is almost obscene, wrong, and outrageous. yet, almost all economists embrace it. though seemingly short-sighted and far-fetched, ours is a discipline that is based on some sort of beauty and simplicity. i must add that “maximizing” behavior does not necessarily mean selfish behavior. actually in recent years, economists have incorporated social preferences in their analysis. economists often postulate that one cares about one’s social status, other people’s welfare, and fairness. economic agents need not be entirely selfish, but they are almost always pursuing an objective. what does this simple maximizing behavioral model buy you? you should ask this question, sooner than later. i do think that it buys you something, and that is consistency. economists have developed a common methodology that is internally consistent for discussing many social issues. a big variety of social issues, topics that used to be in the domain of other social sciences. and you will have to learn to like and appreciate this consistency, this language that economists use. . a manual for graduate study for many students, success in school means success in exams. you are sitting here because you have done very well in exams. at the graduate school, you still have classes to do, and exams to take. you do have to pass some exams in order to continue with the program. however, for the ph.d., classes and exams are only the beginning. exams are - - really not what economics and the ph.d. are about. you will have to go beyond exams, and produce original research. by the way, i hate exams. i was fortunate enough not to have to go through qualifiers, and comprehensive exams that are so common in the us! i really don’t have any exam tips for you. i have not thought about how to do exams for a very long time, and am not about to do it again. let me however emphasize that what you learn from the standard first-year graduate texts is very important. your first-year texts give you the background to understand research papers, which will be the bulk of your economics graduate education. such fundamental materials are not to be taken lightly. do not study these texts only to pass exams, which would be unproductive. papers the papers that you will read are probably all classics. these pieces have probably inspired a lot other works. or they may have made headway in a research agenda. make sure you understand why. the motivation of a paper is always very important. then there may be new techniques, and new ways to study existing problems. again, make sure you understand why. later in your program you may also read new, unpublished working papers. these are state-of-the-art, frontier pieces. often they are exploratory, and may be very hard to read, because the corresponding literature may be immature and incomplete. but you still have to digest them, because very likely you will find inspiration in them for your own research. there is no better way to understand a paper than by doing it yourself. prove the propositions yourself. work out the proofs. see the logic and the elegance of the arguments. nothing is better than working out an example. not an example that is in the paper, but rather an example that you construct yourself. this really puts you in the author’s position. your mind will be like the author’s. you will have to go through the same creative process to get to the results. your mind can really see what is going on. you have to bear in mind that a finished paper may be only a fraction of the author’s work for the project. a lot has been discarded, altered, revised, and improved to get to the final paper. but by working out an example, you may be able to have a glimpse of what has gone on behind the scene. finally, to convince yourself that you understand the paper, explain it to a fellow student. if you have read a micro paper, explain it to a student who is more interested in macro. if you have read a labor paper, explain it to someone more interested in environmental economics. you see, when you try to explain what a paper is all about, your mind really has to pretend that you are the author. see how hard it is to explain a paper to others! if you can crystallize the paper’s ideas into a few short sentences, that’s a very good sign. - - you will read many, many papers. even on the same topic, you will come across many pieces. now the bad thing about the economics profession is that there is no universal notation, or convention. laffont and tirole use the cost of public fund; baron and myerson put more weight on consumer surplus and less on profit, while some simply take net consumer surplus as social welfare. some use the utilitarian social welfare function, some use maxmin, and others use weighted utilitarian, etc. a lot of confusions will occur when you read many papers. you will have to cut through the maze. you must obtain the general principles when papers differ in some technical and modeling details. you will have to decide that some differences between laffont and tirole and baron and myerson are insignificant, while others are critical. for some papers, the literature may have done this for you. researchers that come after laffont and tirole and baron and myerson may have already sorted them out. for others, you may have to do the work yourself. you seldom see the big picture by looking at one paper. you need to look at a set of papers. one paper usually focuses on one or two issues. another paper then tackles another set of issues. but a class of problems contains more than a few. let’s look at public provision of a private good as an example. why? how? what kind of asymmetric information? what kind of actions? how much tax burden? can one or even two papers answer all of them? unlikely. you are talking about a set of papers. all are about a general topic, but each one a little different. so you need a synthesis of papers in the literature in order to understand the topic really well. read broadly, and understand papers in a generic way. mathematics what about mathematics? you must have been wondering. there has been so much emphasis on mathematics in the admission process. how much mathematics should you learn for your ph.d.? economics can be very mathematical, and you may need a lot of mathematics to do mathematical economics. for most of the rest of economics, however, it isn’t that mathematical. nevertheless, most of economics does require a mathematical maturity that few undergraduates have managed to acquire. what do i mean by mathematical maturity? mathematical maturity does not only mean that you can do the n-th order derivative of any function, or find a closed form solution for any integral (although these skills, especially the integrals, can come in handy). nor does it mean that you can memorize the bellman equation, or the fundamental equation of the calculus of variation. [now the fundamental theorems of calculus are different, and you should really know them!] mathematical maturity means that your mind can handle definitions, their implications, and the logical steps to derive results. this is hard, because there is no rule, no procedure, no first-order condition to memorize. it takes experience, practice, and painful mistakes. - - you will have to understand what is meant by a proof. you will have to understand the difference between a definition and a result. you will have to embrace the power of logical reasoning. by and large, we don’t need that much of very complicated logical reasoning in economics. however, you will be better off if you can think in a logical way, and that’s when mathematical maturity can help you. sooner or later, your supervisor will say to you: “this sounds like good intuition, but it requires a proof.” or he or she may say, “you probably guess it right, and i am willing to bet that it’s the right proposition. but you’ve got to prove it.” without the right mathematical background, you may have a problem! with the right background, you may be able to find the mathematical steps to prove it. you can achieve mathematical maturity only by learning and doing---if you are not born with it, that is. so get ready, construct a lot of examples. be ready to play tricks with definitions. here is a riddle i want you to think about. a function is said to have an inverse if it is one to one and onto. we all know that a strictly monotone function has an inverse. now construct a function on a continuous domain that is not monotone and yet it has an inverse! when you have done that, you really can see the difference between monotonicity and one-to-one-onto. do i seem like splitting hairs? yes, i bet. but there is no uncertainty in mathematical statements. either a function has an inverse or it has not; either a function is monotone or it is not. is it really true that monotonicity and inversion are exactly the same? now you’ve got to be very careful. if you need to split hairs to prove a theorem, then that’s the way to do it. now what about the repertoire of mathematics that you should learn? you must have heard of optimization with and without constraints, dynamic programming, nonlinear programming, fixed-point theorems, real analysis, functional analysis, differential equation, etc. each one of these is a serious field of study. you will need to know at least a little of each. in my own experience, analysis and calculus in rn have gotten me quite a long way. the most useful general ideas are choosing a function to maximize something under some constraints, the envelope theorems, and the maximum theorems. the two concepts in mathematics that i myself have found the most use turn out to be continuity and monotonicity, very basic stuff. also, contrary to popular beliefs, in my experience, first- order, second-order conditions and such formulas should be avoided; you should treat them as last resorts because they tend to promote mechanical thinking. i hate first-order conditions so much that once i set an exam in which every optimization problem had a corner solution! the bottom line: do not get bogged down with mathematics. you should learn as much as you need. you should have some solid mathematical skills. specific procedures for the optimization of a certain function subject to certain constraints are less important than the general way to think about constrained optimizations. being able to think about functions - - like they are real objects will serve you very well. you can always find the exact hamiltonian, or euler equation from a book; their exact formulas are less important. being able to visualize a certain function as a solution to a problem is much more valuable. now i want to say that mathematics is a very interesting subject, and you may think that it is an injustice to take a learn-as-you-need approach. but you are not doing a ph.d. in mathematics. you may enjoy mathematics in your spare time, but you will hardly have any spare time in the next few years. . a manual for ph.d. research this is the million dollar question. how does one do research? how does one come up with research ideas? research is a multidimensional process. i am going to concentrate on only a few issues. but let me refer you to a paper by hal varian, “how to build an economic model in your spare time.” you will find lots of tips on coming up with good models and implementing your research. well, i myself run out of ideas quickly. so you should take a look at varian! your own research interest a long, long time ago, a very prominent economist said this to me, “there are those who aim to write papers that would be praised by others. there are those who do research on whatever they feel like doing, and they don’t care a bit whether it is published or not.” after a long pause, he said, “most of us are somewhere in-between.” this is almost true as a tautology, hence not very useful. but it highlights one important thing. your research topic must be something that interests you. you must be enthusiastic to study a problem, analyze it, and solve it. if you want to be praised as the one who proves riemann’s hypothesis, then you by definition are interested in the riemann hypothesis. and if the riemann hypothesis interests you even if you don’t want to be praised, you will be motivated to work on it. (if you don’t know what it is, let me just say that the riemann hypothesis tells you everything you want and need to know about the prime numbers. since i am an economist, let me also mention that there is a us$ million prize on the proof of the riemann hypothesis. and, by the way, the riemann hypothesis, first stated about years ago, is likely to be harder than fermat’s last theorem, which took about years.) to work on something that you are not interested in is a real torture, and something that you cannot endure for very long. so you must find a topic that really interests you. how to approach a research topic? what’s the next step? you likely will find that some other folks have worked on the problem that you are interested in. so by all means find out a little bit about what has - - been done. but perhaps you do not want to find out too much. your mind needs to think about this problem in its own way. your mind should not be completely overtaken by existing ideas. now you have decided that you would like to work on something, say, interaction between physician and patient. and you have taken a quick look at the literature, perhaps keeping in mind what you have learned from the graduate health economics class. and you say to yourself that you want to do something about physicians who really care about their patients. what next? you may want to talk to a faculty member. you should contact a professor who has had some experience in health economics, for example, and who has perhaps some interest in physician-patient interaction. many things may happen after the first or second meetings. you may be asked to read more papers, or to formulate some hypotheses or models for analysis. or you may be told that the topic is rather odd; maybe it is too mature for fresh ideas. or that your particular approach is too arcane. but, the professor may also say that your ideas are interesting, refreshing, and likely to be revolutionary. you should also talk to your classmates. frequently students may be afraid to talk extensively with faculty. first, students fear that professors may not want to spend too much time with them. well, professors are usually busy, and there may be occasions when professors cannot spend too much time with students. second, students fear that professors are too intimidating. indeed, speaking about rough ideas to experienced researchers usually results in quick criticisms. of course, these criticisms may turn out to be useful, but nonetheless may discourage students, and professors may not be very sensitive to that. if you find talking with your classmates more comfortable, then by all means interact with them. to continue let’s say that you have somehow found the professor’s response to be positive and that the avenue for research seems promising. then you start working on the research! what makes a good researcher? work, hard work. i can be more specific. but perhaps it doesn’t hurt to generalize. i think that two things contribute to the success of a ph.d. (or even an academic career): • your intelligence • your work discipline intelligence perhaps we all can agree that not much can be done about intelligence. the technical jargon is that the opportunity cost of changing intelligence is more or less infinity. you either have the minimum iq for a ph.d. or not; you either have the minimum iq for an academic career or not. and changing one’s intelligence seems awfully hard. - - there is, however, something that you should do about your intelligence. and that is to put it to full use. i think that the key is self confidence. if you have self confidence and self esteem, you can use your intelligence fully. self confidence and self esteem are difficult topics, well beyond my expertise as an economist. they are best discussed by real professionals such as psychologists and psychiatrists. i am not about to practice psychotherapy without a license, but can offer you some thoughts. in my experience, people who lack self confidence say “i can’t do this” often. they fail without even trying. or they may try once or twice and then give up all too quickly. conversely, people who are confident of themselves are not that worried about failing. how does one manage to say “i can do this.”? positive thinking helps. here is something that happened to yours truly. a paper of mine got rejected by a leading journal. rejection of a submission is common in our profession, so what’s the big deal? the referee report was the most negative i ever got! in sum it said that my submission was not worth the paper it was printed on. everything was trivial, and the use of mathematics a disgrace. one could be devastated by such a negative report. i could have felt so depressed that working on the paper again would be very difficult. i might have said, “i can’t deal with this anymore.” and the paper would then never see the light of day. but i decided on a positive interpretation. in fact, i thought that the referee was praising me! i wrote so well that the reviewer could understand all the arguments without going through the mathematics. i made the arguments so clear that they appeared trivial. it was the referee who was confused about clarity and triviality, and committed an error of judgment. i decided to submit it to another journal without much delay. if i had stopped, if i had said to myself “i can’t deal with the paper any more,” nothing would have happened. but i decided that “i can deal with this paper.” instead of saying, “i can’t do this,” i said, “i can do this.” a willingness to take risks may eventually build self confidence, which helps you to use your intelligence fully. work discipline well, some people like to think that work habit is like intelligence; it can’t be changed. let’s say you work four hours a day, five days a week. that’s your work habit, and nothing in the world can change that. so, again, not much to be said. but i don’t think that this rigid scenario applies to everyone. or to most of us. make no mistake about it. doing research for a ph.d. is hard work. i have no sympathy for students who party three, four days a week and want to write a dissertation in three, four or even five years. i have no sympathy for students who put priority of vacation over research progress but still want to publish a paper in econometrica. - - most important, it’s your mind that is really doing the research. if you keep thinking about party and holiday, how do you think about research? you really need your mind to work full time, and that requires a focus that many, many people may be found wanting. is this a / job? i wouldn’t say that much, but it is not much less. in my many years in this profession, i have come across more than a few very intelligent economists whose research perhaps is somewhat ordinary. the only reason i can think of is that they don’t particularly want to, or have decided not to, devote their mind power to the research task. i believe that work discipline is something that is entirely your decision. it is up to you to work hard. dedication and will power the combination of the effective use of your intelligence and good work discipline actually translates to dedication and will power. in your research, you need to devote your mind to think about the problem you want to solve. you need to go deep, and explore possibilities that would come about only after long hours of thinking. and i emphasize thinking. you need will power too. research discovery is a poisson process. the probability that you will discover something in the next instant is practically zero. you need to accumulate time, hours, days, weeks even, for a positive discovery, an example, a proof. can you garner your will power to sustain this process? can you handle the disappointment or frustration when for three, four, five months you can’t show what you have wanted to show? you need will power to stay afloat in this business. furthermore, you may need to go over a discovery many times in order to polish it to “perfection.” the first proof of a proposition may be long, tedious, and complicated. you need to simplify it, make it elegant, make the arguments flow smoothly. you may even need to find a new proof. this takes time and effort. again will power, dedication, and persistence are what you need. many of you now think that research is a “challenge” like climbing mount everest. there is a moment of triumph when you reach the summit, and you know that you are at the top of the world. yes, research is a challenge, but the outcome is never quite as clear cut as climbing mount everest. there is no research altimeter that says you are at , feet and there is no higher ground to climb. you may make progress along the way, but may not know if you have done all the best you can. you are climbing a mountain alright, but you have no map, or altimeter. and even when you think that you are there, having discovered something, you need to make it better. an attitude of relentless pursuit of excellence is critical. because research is very much a mind game, you should pay special attention to your mental health. many people find it hard to work well when they are anxious, worried, or otherwise depressed. if you have mental health problems, then your mind will be thinking - - about its own problems, rather than economics. just as you consult a physician when you have problems with physical health, you should consult a mental health professional when you believe that you have a mental health problem. counselors, psychologists and psychiatrists are professionals who may help you. it is a sign of strength for someone to seek help. the weak will only hide and refuse to solve the problems. if you believe seeing mental health professionals is a taboo, that’s wrong thinking. let me emphasize again. your mind is what does the research. this is the driving force behind your discovery. you absolutely need your mind to work towards your research. there are many distractions. there may be personal issues that you will have to sort out. there may be financial issues that bother you. and you may become anxious about, say, living environment, pets, significant others, parents, friends. these distractions degrade your focus. unfortunately, i have no magic bullet to offer you here. it is a fact of life that there are issues and problems that you, and your mind, have to deal with. and sometimes these are not problems of economics research. at some point, you may want to relax, try not to be so hard on yourself. make a decision about priorities. sort out problems. you may decide that research is not the most urgent or critical thing for you to handle. that’s perfectly ok, and nobody will think the lesser of you. it is a perfectly fine decision to set aside a ph.d. in order to handle some other problems. is there a tradeoff between intelligence and work discipline? you might have thought that i would say, no, there is no tradeoff. but surprisingly i think that there is. it’s a tradeoff that, i believe, favors work discipline. i am willing to give up quite a few iq points for a superior work discipline. i am willing to be less smart, less sharp, less quick, in order to be able to concentrate on a problem for a longer period of time, and to focus more intensely on a research topic. i bet that, unless you are talking about the very, very top pioneers, the difference in intelligence among most academics must be very small. what makes a good researcher is one’s ability to lock the mind onto one problem. “keep going,” “just keep going,” “keep thinking about it,” “don’t give up.” these will serve you very well. sir peter medawar, a british nobel laureate biologist was quoted as saying, "one does not have to be terribly brainy to be a good scientist,” and "one would do better for owning some of those old- fashioned virtues---application, diligence, a sense of purpose, the power to concentrate, to persevere and not to be cast down by adversity." and there is one other very important reason why i favor work discipline over intelligence. this is a factor that likely only has a marginal effect on you, but i should mention it here. it is experience. you will not appreciate it yet, but research experience matters a lot, a whole lot. if you have good work discipline, you work better, and you accumulate research experience. it’s a snowball effect. more research experience helps with future research. i will come back to experience a little later. - - writing your thesis this is exactly the skill that no economics graduate school will teach you, and so i deem it my real responsibility to mention it here. let me state it very simply. writing a paper requires a lot of skill and experience that most graduate students simply don’t have. for so many years, i have wondered why graduate schools in the world do not include critical writing as a required course! here are the most common mistakes found in dissertations: • this is the history of my research. everything that i did is included. • here are my thoughts on the research topic, in no particular order. • the pages to follow contain the chaotic calculations required to prove the results. • the sentences are incomprehensible; the flow of the argument is like the many small rivers going through the fjords, very steep, very hard to see, and disorganized. • you read this at your own expense of hiring an english (or any other language) editor. what do you want to do when you feel like you have all the results? naturally, you want to write them up, and have a paper, a chapter of your thesis. writing it up is exactly the wrong attitude. good writing is good thinking. clear writing is clear thinking. critical writing is critical thinking. good writing is a skill that requires practice, training, and, yes, thinking. just writing it up is going to be a disaster. even many published papers are poorly written. haven’t you read this sequence before in published papers? “roughly, the intuition is this…” “more precisely, the argument is that…” “finally, formally, the mathematics goes like this…” this is exactly what bad writing is like. what is the point of a convoluted way of stating your ideas? presenting your model, arguments, and results is not leading your reader on a wild goose chase. let me make a few analogies. what do you think trial lawyers do when the detectives, clerks or assistants have gotten them all the “facts” of the case? what do you think movie directors and producers do when the shooting is done? what do you think newspaper and magazine editors do when they have received all the scripts from authors or wire services? they have to do a lot of work to present whatever they have in a motivated, coherent, convincing, and clear way. they cut, request revisions, demand elaborations, and organize. much work needs to be done before the final product is ready. the editorial process requires a lot of work. scientific writing has one and only one goal, and that is to present the ideas and results precisely, without any possibility of confusion and misunderstanding. to do that requires a lot more work than most graduate students can even begin to contemplate. what’s - - more, writing a paper requires on-going research. if i spend six months “proving” the results i want to find, i expect to spend another six months “writing them up.” why? because when i write a paper, i always have to adjust the results, prove new stuff, think about the motivation even more, organize the results in various, combinatorial fashions, and engage in endless rounds of “relentless pursuit of excellence.” moreover, you need to work on the manuscript in ways that you cannot even imagine now. what may have been a part of section , after some thought and work, may be more suitable to be in section . you need to iterate back and forth between sentences, paragraphs, sections to find the right approach. your goal is to present your ideas in the clearest and most attractive way. how do you become a good scientific writer? hard work, no doubt, you say. that is absolutely true. but this is hard work that requires the kind of training unavailable from economics classes that you will attend. you need some specialized training in writing skills. and it is unlikely to come from topics in advanced economic theory or econometrics. check out the english department. i can’t possibly share with you experiences about writing in a lecture. but there is plenty out there that you can resort to. you can even begin by being a good reader. notice how good scientific writers do their job. notice how easy it is to read papers that are well written. notice how clear the arguments are when they are made by a good writer. on the other hand, be critical. when you read a paper, think about how you can improve it. can the arguments be presented differently? can the points be made more clearly? can you rewrite some of the sentences, or paragraphs to improve them? whether you like it or not, whether you think it is fair or not, the majority of economics papers are to be published in english. it follows that english is the language in which you will express your economics. therefore, it pays to learn english well. norwegians already are ahead in the game since they speak good english. let me say, however, that there is some difference between spoken english and written english, especially the scientific kind. you should pay special attention. even native english speakers may be poor english writers! i cannot go on with writing skills. let me mention a few books. there is the classic “elements of style” by strunk and white. (yes, e.b. white, the author of charlotte’s web. have you seen the movie?) strunk and white was written almost a hundred years ago (a little bit exaggerated), but it’s so strikingly relevant even today. strunk and white is also very elementary. the stuff in there is something you must know. then there is “economical writing” by mccloskey. this little book is written by an economist for economists. obviously the book itself is very well written. mccloskey also has written many other books. reading them will make you appreciate what good economics writing is all about. i have read “economical writing” many times, and often i would disagree with the author. that, i guess, is a good sign. if i can disagree, it means that i have thought about those issues. again, good writing is good thinking. - - finally, let me mention “a guide for the young economist” by thomson. this book is more general, as the title suggests, than just writing. but i thought that this is the right place to bring it up. it includes many tips and suggestions for young minds. if you have no idea that “writing up” your thesis requires skills, well that’s a rude awakening. but since you are only just beginning, you have plenty of time to acquire those skills. . what your supervisor can and cannot do for you you must feel happy that you are going to have a thesis supervisor. you should be glad that you will do research with guidance. it may also be a very nice experience since you may interact with another beautiful mind. now you may or may not have more than one supervisor. and you may work with someone who is not officially your supervisor. for the purpose of this talk, i am going to ignore these details. let me assume that you have one supervisor. (now if you appreciate this assumption, you are beginning to think as an economist. by the way, an assumption should always buy you something at a reasonable cost. otherwise, don’t make it. so think about what this assumption does buy me, and what is its cost.) your supervisor is very likely the most important person to help you with your ph.d. research. there is a first principle about your supervisor that i would like you to know. yes, your supervisor is an economist, and a professor. but ma’s first principle is that your supervisor is human. remember that your supervisor also has to do grocery shopping, plan for vacations, fix the toilet, and cook dinners. two things about humans you must recognize: they are all very different, and none of them is perfect. your supervisor’s mind human beings exhibit a lot of diversity: they have different genders, races, ages, physiques, demeanors, personalities, etc. human beings’ minds can be very different. even economists, who share some common intellectual traits, language, and background, have minds that operate in their unique ways. you should try to understand how your supervisor thinks. you should try to understand your supervisor’s style. read a couple of your professor’s papers, especially working papers. try to understand what ideas are occupying your professor’s mind. here is an example. i like graphs, and i can’t remember kuhn-tucker conditions. so when i have a constrained optimization problem, i draw some pictures, or try to figure out which constraints are binding. that’s how i think about it. when a student gets stuck with such a problem, that is how i would try to help. now suppose that a student has a problem that is absolutely -dimensional, and there are inequality constraints so complex that graphs and guesses are not useful, i can’t be of much help. but another - - professor who absolutely adores mathematica or maple, or any other artificial intelligence program may handle it in stride. and if your research must involve - dimensional- -inequality-constraint problems every day, even if it is in health economics, i would not be interested. nor can i be very helpful. let me give you another example. when i write a paper, i use short sentences, many paragraphs. i hate writing a paper longer than pages. i would use double spacing between lines. naturally i would steer my students to write short sentences, separate ideas into short paragraphs, and avoid papers that are too long. it would be useful if my students would consider this style when working with me. it’s an imperfect world the next thing you must recognize is that human beings cannot be perfect. we all have our own shortcomings, be they intellectual, personality, or demeanor. you must learn to work with an imperfect supervisor; likewise, supervisors, i think, would have to work with imperfect graduate students. the important words are “work with.” working with someone means compromise, communication, and recognizing weaknesses and strengths. does it sound like a skill in interpersonal relationship? yes, indeed, it does. you do well acquiring some skills in interpersonal relationship. because you need to intellectually connect with your supervisor, communication is the key to that connection. i believe that the key to successful communication is mutual respect. you and your supervisor should take each other seriously. you will likely hear suggestions from your supervisor. think about them before you agree or disagree. pay some attention. this effort actually helps to establish your supervisor’s respect for you. your supervisor should also recognize your strength and weakness. you can also bring to your advisor’s attention your own strength and weakness. that will help. you must remember, however, that thesis supervisors tend to be pushy. they tend to be demanding, asking for more, wanting a better paper all the time. this is a professional habit that you simply cannot change. after all, this relentless pursuit for excellence has helped most professors to survive in academia. sometimes they may forget that it is unproductive to ask students to do what they can’t or wouldn’t do. if you find your professor too demanding, raise your concern. speak about your limited ability. letting your supervisor know about your weakness can only help you. let me list a few things that your supervisor cannot do for you. • your supervisor cannot write your thesis. • your supervisor cannot always make correct conjectures. • your supervisor cannot check the proof of every proposition or verify every test. • your supervisor cannot correct all grammatical errors. • your supervisor cannot know all the literature. - - you probably wished that your thesis advisor could do all the things i have listed above. remember, we live in an imperfect world. no supervisor can provide all the things above. most supervisors cannot even provide one of these! let me emphasize that you will have to find the right supervisor. what would happen if you found the wrong supervisor? for example, if you are interested in macro and somehow you keep talking with me, maybe about calibration or high-order differential equations, and somehow i have failed to kick you out of my office, then you will be wasting your time. you see, ph.d. research is quite specialized. you must have a common research interest with your supervisor to embark on a fruitful research relationship. finally, what should you do if you feel that working with your supervisor has been a mistake? suppose your progress is unsatisfactory. it appears to you that it has not been a good match between yourself and the supervisor. and you believe there is no more help from your supervisor. you should decide to change to a different supervisor if the work relationship is not helping you in any way. your supervisor is being paid to guide you, and if the match is unsatisfactory, you should find another. you might fear that this would make your supervisor angry, and might even jeopardize your career! i can’t speak for others, but for myself, there is no better news than a student telling me that he or she wants to work with somebody else! it means that i get paid but having to do no work! more important, i have one less thesis to worry about! if you have any concern, talk to your supervisor openly and in a courteous manner. you will likely find that professors are reasonable people. experience now your ask, what is it that you can expect from your thesis advisor? i would say that the most valuable benefit you can get from your supervisor is his or her experience, which i touched upon a little earlier. sometimes your supervisor may give you a problem to work on. or you may have started on a problem on your own. but as the research continues, there will be decisions to make. no theoretical model is perfect. no data set is complete. you always have to make compromises. your supervisor has made many such decisions before. it may take you three weeks to find out that an assumption is either too strong or too weak. but your supervisor may be able to tell you that in a couple of hours. why? because some years ago, your supervisor was in a similar situation and did take three weeks to find that out! you see, economists don’t believe in free lunch, but they have to believe that sharing research experience is rather free. you will often read or hear about “standard” ways of solving a model. as you study research papers, you realize that they are not nearly standard! the mathematical details are long, or the statistical properties difficult to state. how can they be standard? you ask - - your supervisor about them, and then you are surprised when your supervisor says that these are standard methods. why? because your supervisor has probably used these complicated procedures hundreds of times. familiarity breeds skills. so your thesis advisor can guide you through problems by telling you, for example, that there are standard ways to handle them. let me talk about another aspect of experience. you think you have an interesting problem, and spend three months trying to prove a major theorem. after three months, you are exhausted, disappointed, and realize that either the proof isn’t right or the theorem isn’t true. here again your supervisor might have helped. your professor can likely tell you whether some theorem sounds too good to be true, or requires a proof that has eluded researchers for decades. why? again, your professor might have experienced the same pain before. experience helps one to spot promising results, avoid mistakes, draw a connection between your current research and known results, and recognize that a research agenda is hopeless. you, as a graduate student, lack experience. your supervisor has a lot more experience. if you do not make use of your supervisor’s experience, what kind of an economist are you (or will you become)? collaboration the work relationship with your supervisor may be so good that you decide to write a paper together. you feel very excited to be able to do this. this will be a very rewarding experience for you. now you have a first-hand experience to see how a real professional handles a problem, finds solutions, writes the paper, deals with journals, etc. joint authorship has become very common in economics. if i have five active projects, i may have n coauthors, where n may be between five and ten! it is truly a very rewarding experience to collaborate with a fellow economist. i strongly encourage you to try it. there is one thing i must warn you though. the market is a search engine for talents. joint authorship, by definition, contaminates the revelation of information. the technical jargon is signal-jamming. when you collaborate with someone who is much more senior, the rest of the world may downgrade your contribution. in a sense your supervisor may become a signal-jamming agent. this is insignificant if you have coauthors and of them are more senior. but if you have written one and a half papers and one of them is with your supervisor, then perhaps the market may become confused. i do not want to exaggerate this signaling issue. the market will filter out the noise. if you are good, i believe that the market eventually will recognize it. it is such a satisfying experience working with a senior economist that i myself would never hesitate. there is, however, a way to avoid signal jamming when you work with others at the beginning of your career: collaborate with someone in your own cohort, such as a classmate. you will find this a very rewarding experience too. the rest of the world will hardly have any reason to doubt your contribution. - - the last laughs what do you think is the most “serious” complaint made by professors against their students? you might have thought it must be “they are lazy,” “they are not very smart,” or “they are slow.” i have heard these complaints before, all of them. but the one complaint made by professors against students that almost always is expressed with disappointment and sometimes even anger is “they don’t listen!” your supervisor is usually heart-broken when you learn it the hard way. he might shake his head and said that if you had listened, things might have been better. here, i think perhaps professors also have something to learn. many students can only learn it the hard way. somehow, for some learners if the disutility of a mistake is low, the experience becomes trivialized, and it doesn’t stick to the mind. the mind does remember painful experiences, however. you may decide to ignore your advisor’s suggestion of a better introduction to the paper. you submit the paper to a journal, as is. a few months later, the rejection letter arrives, and it says that the introduction is poorly written. now in your revision, you really spend some time and effort to write a good introduction. why? because ignoring your advisor’s suggestion doesn’t seem to carry any immediate penalty, while the paper getting rejected by a journal is a painful experience. here i am a professor. so i can’t help but say, “make an effort to listen to your professors. it might just pay off.” . a journey for your mind and so i have told you a little about modern economics and graduate study and research. it will be a journey for your beautiful mind. it is an experience for the privileged few. only a small percentage of people gets to work on a ph.d. you should understand that you are doing something that most of the general population never gets to experience. what are the goals in your graduate study and research? i think that there are two. first, you have an opportunity to add to knowledge of economic science. second, and i think this is actually more important, you have an opportunity to learn to become an independent researcher. the first goal is obvious. you need a thesis to graduate. your dissertation should be a significant contribution to economic science, and you have to do that to earn your degree. the second goal is more general. you may or may not want to continue in the academic profession. you may choose to do things other than economics after your ph.d. in fact, many people with economics ph.d.s are working in areas totally unrelated to economics. but these do not change the nature of your graduate study. you are learning to become - - independent researchers. and i stress “independent.” independence is part of maturity. as your mind grows and becomes mature, you will realize that this journey for your mind will indeed be an important part of your life. i have not described a very easy journey ahead of you. i have mentioned hard work many, many times. moreover, your department and professors offer you no guarantee. but then you have to realize that most good things in life require hard work, and don’t come with any guarantee. adding to the existing knowledge of economic science, and becoming an independent researcher are all tremendously difficult, even risky, and require great efforts. but it is all very satisfying. i have had such a wonderful experience that i would do it again. so let your beautiful mind go on this journey. - - references mccloskey, deirdre n., economical writing, waveland press, illinois, . sen, amartya, “rational fools: a critique of the behavioral foundations of economic theory,” philosophy and public affairs, vol. , no. (summer ), - . strunk, william jr., and e.b. white, the elements of style, fourth edition, pearson education company, massachusetts, . thomson, william, a guide for the young economist, mit press, masschusetts, . varian, hal, “how to build an economic model in your spare time,” in passion and craft: economists at work, michael szenberg (ed), university of michigan press, . norges handelshøyskole norwegian school of economics and business administration nhh helleveien no- bergen norway tlf/tel: + faks/fax: + nhh.postmottak@nhh.no www.nhh.no << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /all /binding /left /calgrayprofile (dot gain %) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /tags /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /leavecolorunchanged /dothumbnails false /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - 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/monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname (http://www.color.org) /pdfxtrapped /unknown /syntheticboldness . /description << /fra /jpn /deu /ptb /dan /nld /esp /suo /ita /nor /sve /enu (use these settings to create pdf documents with higher image resolution for improved printing quality. the pdf documents can be opened with acrobat and reader . and later.) >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice available on cms information server cms cr - / the compact muon solenoid experiment mailing address: cms cern, ch- geneva , switzerland conference report july (v , july ) open beauty measurements in ppb collisions with cms hyunchul kim for the cms collaboration abstract we report the first measurements of fully reconstructed b mesons in collisions involving heavy ions. rapidity and transverse momentum cross sections, measured at √ sn n = . tev with the cms detector, will be presented. for the same collision system, we will also report on the production of inclusive b-hadrons identified via their decays into j/ψ displaced from the primary collision vertex, and measured in a similar kinematic range as the identified b mesons. the nuclear modification factors, which are constructed using a theoretically calculated pp reference, will be shown together with cross-section asymmetries between equivalent positive and negative pseudo-rapidity ranges in the center-of-mass frame of the collision. presented at qm quark matter nuclear physics a ( ) – nuclear physics a open beauty measurements in ppb collisions with cms hyunchul kim (for the cms collaboration) korea university, seoul - , republic of korea abstract the b+, b , and b s mesons are exclusively reconstructed in proton-lead (ppb) collisions at √ sn n = . tev by the cms collaboration at the large hadron collider (lhc). the cross sections are measured in the range of transverse momentum of to gev/c and the center-of-mass rapidity smaller than . . the nuclear modification factor for each particle species is estimated using theoretical calculations as the pp reference, and the experimental data are consistent with unity within the current uncertainties. the forward-to-backward asymmetry of b+ is also analyzed and does not show any nuclear effect in the measured rapidity range. keywords: b meson, ppb collision, cms . introduction the heavy quarks generated in high-energy proton-proton (pp) collisions are useful to test perturbative quantum- chromodynamics (pqcd) because they are produced in the hard processes. in addition, they are also useful to probe the hot and dense qcd medium via their interactions with the matter over the course of their propagation. on the other hand, there may be effects not related to hot nuclear matter, such as nuclear modifications to the parton distri- butions. ppb collisions may be used to isolate such effects as they are not expected to form an extended hot medium. taking advantage of the large cross section of b quark production at the lhc, the cms collaboration has measured the production cross sections of various b mesons, for the first time, in ppb collisions at √ sn n = . tev. previously, the cms collaboration studied the b-hadron production in pbpb collisions at √ sn n = . tev by using inclusive non-prompt j/ψ in the and data sets [ ]. the analysis technique developed for non-prompt j/ψ has been extended to the exclusive b reconstruction via the combination of one or more charged particle tracks to the reconstructed j/ψ in the ppb collisions at √ sn n = . tev recorded in . the b-meson species analyzed for this study are b±, b , and b s that consist of u (or ū), d (or d̄), and s (or s̄) quark, respectively, in addition to the b (b̄) quark. although each b meson has many decay modes, the specific decay channel for j/ψ and a strange meson is selected for this analysis. here, j/ψ is reconstructed from opposite charge-signed muon pair and the associated decay mesons are k±, k∗ ( ) and φ, respectively. then, k ∗ ( ) and φ are reconstructed by k+π− (or its charge conjugate k−π+) and k+ k−, respectively. note that in this document the contribution from the corresponding antiparticles is implicit in the notation for b+, b and b s . the detailed description of the cms detector elements are given in ref. [ ]. among them, this analysis primarily uses the inner tracker and muon systems. the inner tracker system is located in the . t magnetic field generated by the superconducting solenoid, and consists of silicon pixel and silicon strip detector modules with a list of members of the cms collaboration and acknowledgments can be found at the end of this issue. h. kim, et al. / nuclear physics a ( ) – ) (gev/cbm . . . . . . . . . ) e n tr ie s / ( m e v /c = . tevnnscms preliminary ppb - l = . nb +b < gev/cb t
gev/c. the standard criteria are applied to remove electromagnetic and beam-gas collision events [ ]. the b reconstruction starts with the muons that are reconstructed from the inner tracker system and the outer muon system. the muons must satisfy the muon selection criteria including the kinematic limits imposed by the geometry of the detectors: pt > . gev/c for |η| < . , p > . gev/c for . < |η| < . and pt > . gev/c for . < |η| < . . the opposite-signed muon pairs with invariant mass within ± mev/c of the nominal j/ψ mass found in the particle data group [ ] are used for further analysis. the charged hadrons are reconstructed by the inner tracker system within |η| < . in the laboratory frame. for the reconstruction of b+, the kaon mass is assigned to each charged particle and, then, the invariant mass distribution of j/ψ and kaon candidates are produced. the b and b s analyses are more complicated than the charged b’s as they decay into the intermediate states which can be reconstructed by the two charged hadrons. therefore, for the reconstructions of b and b s , the pion and kaon masses are assigned to any pair of the charged particles. to reduce the amount of background, each b candidate is required to pass optimized cuts, such as the χ of the secondary vertex fit, the distance between the primary and the secondary vertices (normalized by its uncertainty) and the cosine of the angle between the momentum vector of b and the position vector of the secondary vertex measured from the primary vertex in the transverse plane, etc. for the b and b s reconstructions, additional constraints on the respective proper mass window of the invariant mass for the intermediate meson states are imposed. when multiple b mesons are reconstructed in one event, the candidate with the best χ of the secondary vertex is chosen because of the possible double counting, especially, for the b case. . results all b candidates are reconstructed in < pt < gev/c and |yc m| < . in the center-of-mass frame. fig- ure shows the invariant mass distributions of b+, b and b s in their respective lowest pt bin. the combinatorial h. kim, et al. / nuclear physics a ( ) – (gev/c) t p p a f o n l l r . . . pa fonllr syst. l+br syst. err. from fonll pp ref. pa fonllr syst. l+br syst. err. from fonll pp ref. = . tev nn scms preliminary ppb - l = . nb| < . cm |y + b (gev/c) t p p a f o n l l r . . . pa fonllr syst. l+br syst. err. from fonll pp ref. pa fonllr syst. l+br syst. err. from fonll pp ref. = . tev nn scms preliminary ppb - l = . nb| < . cm |y b (gev/c) t p p a f o n l l r . . . pa fonllr syst. l+br syst. err. from fonll pp ref. pa fonllr syst. l+br syst. err. from fonll pp ref. = . tev nn scms preliminary ppb - l = . nb| < . cm |y sb figure . nuclear modification factor rfon llpa for b + (left), b (center), and b s (right) within |yc m| < . as a function of pt in ppb collisions at √ sn n = . tev. the fonll calculations are used as the pp references with the yellow areas representing the theoretical uncertainties. the vertical bars represent the statistical uncertainties, and the boxes around the data points display the total systematic uncertainties. the grey areas at pt = gev/c represent the systematic uncertainties from the luminosity and the branching ratios of the decay channels. backgrounds, fitted by first or second order polynomial functions, are dominated by inclusive j/ψ’s and charged hadrons associated with different mother particles. in addition, the so-called peaking background is caused by the mis-reconstruction b mesons shown by the green hatched areas in fig. . in order to understand the signal and background shapes the monte-carlo simulations have been intensively per- formed. the particles in the monte-carlo samples are generated by the pythia event generator [ ] and decayed by the evtgen particle decay simulation package [ ]. the initial and final state radiations are controlled by the photos package [ ]. furthermore, the signal particles are embedded in the hijing minimum-bias events for ppb collisions to mimic more realistic environment [ ]. after the estimated backgrounds are properly subtracted, several functions are tried to fit the signal peak shapes for each channel. finally, each signal peak is fitted by the sum of two gaussian functions. the differential cross section for each b species has been obtained by dσb d pt ∣∣∣∣∣∣ |yc m |< . = ∆pt n b ∣∣∣ |yc m |< . (α× �) · br ·l , ( ) where ∆pt is the width of the pt bin, α is the geometrical acceptance, � is the efficiency estimated by the monte-carlo simulation, br is the branching ratio of the decay mode, and l is the integrated luminosity. note that the additional factor of / is multiplied to take into account the charge conjugate of each quark consisting b meson such as b− for b+. for this analysis, the fixed order plus next-to-leading logarithm (fonll) calculations [ , ] are used as the pp reference because the experimental pp data are not yet available at . tev. note that fonll has successfully reproduced the cdf data at . tev and the cms/atlas data at tev within the experimental and theoretical uncertainties [ , ]. using the analyzed differential cross section data and the fonll calculations, the nuclear modification factors are calculated by rfon llpa ( pt ) = (dσ/d pt )ppb a × (dσ/d pt )pp , ( ) where the number of nucleons in pb, a, is introduced for normalization. the preliminary data on rfon llpa for b +, b and b s are shown in fig. . considering the systematic and statistical uncertainties, r fon ll pa ’s for all three particle species are consistent with unity and, thus, significant cold nuclear matter effects are not observed. the left panel of fig. shows the differential cross section as a function of rapidity in the center-of-mass frame for b+ with the most statistics among the three analyzed particle species. although the most backward data point toward the pb-going side is higher than the others, the experimental uncertainties are large and the rapidity dependence cannot h. kim, et al. / nuclear physics a ( ) – cm y - . - - . - - . . . . b ) µ( c m / d y σd ppb fonll pp ref. < gev/c t b < p = . tev nn scms preliminary ppb - l = . nb < gev/c t b < p + b | cm |y . . f b r . . . stat.fbr syst.fbr = . tev nn scms preliminary ppb - l = . nb + b < gev/c t b < p figure . differential cross section as a function of rapidity (left) and the forward-to-backward asymmetry rf b (right) of b+ in the center-of-mass frame of ppb collisions at √ sn n = . tev. the vertical bars represent the statistical uncertainties, and the boxes around the data points display the total systematic uncertainties. the yellow areas for rfon llpa are the theoretical uncertainties for the fonll calculations. be claimed. in addition, the right panel of fig. displays the distribution of the forward-to-backward asymmetry rf b for b+: rf b = ncorrectedf orward ncorrectedbackward , ( ) where the forward and backward imply the proton- and pb-going directions, respectively. the preliminary data for rf b of b+ are consistent with unity, and the large uncertainties prevent any conclusion on the rapidity dependence. . conclusions the b+, b , and b s mesons are exclusively reconstructed in ppb collisions at √ sn n = . tev by the cms collaboration at lhc. the range of transverse momentum covered is to gev/c, for the rapidity range (evaluated in the center of mass) of |y| < . . statistically significant peaks are observed for all three b-meson species in the invariant-mass distributions. the nuclear modification factors (rfon llpa ) for all three particle species are estimated using fonll calculations as pp references. the nuclear modification factors are consistent with unity within the current uncertainties. the forward-to-backward asymmetry (rf b) of b+ is also analyzed, and it does not show any modification in the measured rapidity window. presently, the cms collaboration is preparing for the next lhc run in with the highest beam energy. the present results will be compared with the b meson data in heavy-ion collisions in the future. references [ ] cms collaboration, jhep ( ) . [ ] cms collaboration, jinst ( ) s . [ ] cms collaboration, eur. phys. j. c ( ) . [ ] particle data group collaboration, phys. rev. d ( ) . [ ] t. sjöstrand, s. mrenna, and p. skands, jhep ( ) . [ ] d. j. lange, nucl. instrum. meth. a ( ) . [ ] e. barberio, b van eijk, and z. was, comput. phys. commun. ( ) . [ ] x.-n. wang and m. gyulassy, phys. rev. d ( ) . [ ] m. cacciari, s. frixione and p. nason, jhep ( ) . [ ] m. cacciari, m. greco and p. nason, jhep ( ) . [ ] cdf collaboration, phys. rev. d ( ) . [ ] atlas collaboration, jhep ( ) . cost of beauty; prilocaine induced methemoglobinemia güzelliğin bedeli; prilokaine bağlı gelişen methemoglobinemi olgusu case report department of emergency medicine, baskent university faculty of medicine, ankara elif kilicli, gokhan aksel, betul akbuga ozel, cemil kavalci, dilek suveren artuk Özet prilokaine bağlı gelişen methemoglobinemi nadir görülen bir du- rumdur. bu yazıda epilasyon öncesi kullanılan prilokaine sekonder gelişen methemoglobinemi olgusunu sunarak nadir görülen bu durumun önemine işaret etmek istiyoruz. otuz yaşında kadın acil servise baş ağrısı, dispne ve siyanoz şikayetleri ile başvurdu. hasta- ya beş saat öncesinde bir güzellik merkezinde epilasyon öncesinde yaklaşık - mg prilokain subkutan enjeksiyonu yapıldığı öğrenildi. başvuruda kan basıncı / mmhg, nabız /dk, vü- cut ısısı °c ve solunum sayısı /dk olarak kaydedilmişti. hasta- nın akral siyanozu belirgindi. venöz kan gazında methemoglobin düzeyi % . olarak ölçüldü. hastaya g intravenöz askorbik asit uygulandı. tedavi sonrası semptomları gerileyen ve komplikasyon geliştirmeyen hasta saat sonra taburcu edildi. acil servis doktor- ları, prilokain enjeksiyonu sonrası gelişen dispne ve siyanoz ayırıcı tanısında mutlaka methemoglobinemiyi akla getirmelidirler. anahtar sözcükler: methemoblobinemi; prilokain; siyanoz. summary prilocaine induced methemoglobinemia is a rare entity. in the pres- ent paper, the authors aim to draw attention to the importance of this rare condition by reporting this case. a -year-old female presented to emergency department with headache, dispnea and cyanosis. the patient has a history of - mg of prilocaine subcutaneous injection for hair removal at a beauty center, hours ago. tension arterial: / mmhg, pulse: /minute, body tem- perature: °c and respiratory rate: /minute. the patient had ac- ral and perioral cyanosis. methemoglobin was measured . % in venous blood gas test. the patient treated with gr ascorbic acid intravenously. the patient was discharged free of symptoms after hours of observation. emergency physician should consider methemoglobinemia in presentation of dispnea and cyanosis after injection of prilocaine. key words: methemoglobinemia; prilocaine; cyanosis. introduction hemoglobin (hb) is a molecule which carries oxygen from respiratory organs to the rest of the body. hb binds to iron in a ferrous (fe +) oxidation state under normal conditions. however, the existence of oxidative stress is known to trans- form iron to ferric iron (fe +). upon oxidation, hemoglobin or methemoglobin (methb) cannot bind to oxygen molecules. in methemoglobinemia, the hb is unable to release oxygen effectively to body tissues. while mild forms of methemo- globinemia can be asymptomatic, cyanosis, tachypnea, tachycardia, hypotension, confusion, and even death can be seen in the more severe cases.[ ] there are three common causes of methemoglobinemia, including hemoglobinopa- thies, hereditary enzyme deficiencies (nadh methb reduc- tase), and exposure to drugs. interestingly, hemoglobin- opathies and hereditary enzyme deficiencies (nadh methb reductase) are the least common causes, whereas exposure to drugs is the most common.[ ] many chemicals and drugs had been reported to cause toxic methemoglobinemia, including nitrite, nitrate, chlorate, qui- turk j emerg med ; ( ): - doi: . / . . . submitted: august , accepted: november , published online: january , correspondence: dr. gökhan aksel. başkent Üniversitesi tıp fakültesi ankara hastanesi, mareşal fevzi Çakmak mah., . sokak, no: , bahçelievler, ankara, turkey. e-mail: gokhanaksel@gmail.com turk j emerg med ; ( ): - nine, aminobenzene, nitrobenzene, nitrotoluenes, phenac- etin, chloroquine, dapson, phenytoin, sulphonamides, and local anesthetics.[ ] methemoglobinemia, caused by prilo- caine a local anesthesia is rare.[ ] prilocaine, a derivative of toluidine, is an amide local anesthetic and has been shown to produce high methb levels.[ , ] because of its rarity, our knowledge about treatment use is limited. in this paper, we discuss a treatment strategy using ascorbic acid for a patient diagnosed with methemoglobinemia by prilocaine. re- search targets and strategies to understand best treatment strategies will be discussed. case report a -year-old woman was admitted to emergency depart- ment (ed) with complaints of tachycardia, headache, dys- pnea, and cyanosis. it was learned from her history that she was anesthetized with . - vials ( - mg?) of prilo- caine (citanest®) subcutaneously before a laser hair removal procedure. although the severity of the symptoms de- creased at the time of ed admission compared to the initial time point, her symptoms were still ongoing. the patient’s medical history was unremarkable. the tension arterial rate was / mmhg, pulse rate was /minute, body tem- perature was °c, and respiratory rate was /minute. the pulse oximeter measured o saturation as %, and she had acral cyanosis. electrocardiography revealed sinus tachycar- dia with a rate of /minute. chest radiograph, complete blood counting, renal function tests and electrolytes were all in the normal range. venous blood gas analyses revealed methb as . %. despite treatment with l/minute o , her symptoms were still continual. she was admitted to the in- tensive care unit and grams of ascorbic acid was given in- travenously. two hours after treatment, control methb was measured as . %, and the patient was free of symptoms and with no complications. she was discharged as healthy upon a hour of follow up period. discussion prilocaine at therapeutic doses ( - mg/kg) can cause lim- ited methemoglobinemia without cyanosis.[ ] the maximum safe dose of prilocaine is mg/kg (maximum of mg) as a single injection.[ ] in this case, - mg of prilocaine was administered, in which the limits were highly exceeded. the effects of local anesthetic induced methemoglobinemia are known and include seizures, respiratory compromise, myocardial infarction, shock state, coma, hypoxic encepha- lopathy, and death. in a retrospective study it was reported that most patients with a methemoglobin (≥ %) were symp- tomatic.[ ] in methemoglobinemia resulting from chemical substances, the first step of treatment is to avoid further exposure. if methemoglobinemia is under %, spontaneous recovery is usually observed after drug avoidance, but treatment may be necessary in newborns and infants.[ ] methylene blue, ascorbic acid, and riboflavin have been suggested as treat- ment modalities.[ ] methylene blue should be administered - mg/kg intravenously in five minutes, and repeated one hour later if adequate improvement is not observed.[ ] it is contraindicated in patients with glucose phosphate dehy- drogenase deficiency because administration of methylene blue can cause aggravation of methemoglobinemia, chest pain, cyanosis and hemolytic anemia.[ ] in such cases, ascor- bic acid can be considered as an antidote.[ , ] hyperbaric oxygen therapy and exchange transfusion is another option if methb level is over %. ascorbic acid reduces methb by a non-enzymatic processes in animal and human erythrocytes in vitro, which makes ascorbic acid a candidate for treatment of methemoglo- binemia.[ , ] it is most commonly used orally in long term treatment of patients with hereditary methemoglobinemia. [ ] although, methylene blue can be a first choice treatment of methemoglobinemia, if there is limited experience in the use of ascorbic acid in toxic methemoglobinemia.[ ] al- though methb was measured relatively less ( . %) in the present case, there was an indication of antidote therapy due to the patient being symptomatic. in addition, ascorbic acid was chosen because a limited supply of methylene blue in the hospital. after administration of ascorbic acid, methb was measured as . % and she was asymptomatic. aydogan et al. reported that two patients with methemoglobinemia recovered after ascorbic acid administration.[ ] tekbas et al. also reported an improvement in a patient with combined treatment of methylene blue and ascorbic acid caused by methemoglobinemia due to prilocaine given before intra- vascular laser therapy.[ ] conclusion methemoglobinemia resulting from the usage of prilocaine within and out of hospital is a major concern. methemoglo- binemia should be considered in patients who had cyanosis after local anesthetic administration. in cases which methy- lene blue could not be used as an antidote, ascorbic acid can be a safe alternative. conflict of interest the authors declare that there is no potential conflicts of in- terest. references . honig gr. hemoglobin disorder. in: behrman re, kleigman rm, jenson hb, editors. nelson textbook of pediatrics. phila- delpiha: saunders; . p. - . . aygencel sg, akinci e, pamukcu g. prilocaine induced methe- moglobinemia. saudi med j ; : - . . tabel y, sandikkaya a, gungor s, ozgen u. methemoglobin- emia after injection of prilocaine for pre-medication of cir- cumcision. [article in turkish] j dicle med school : : - . . coleman md, coleman na. drug-induced methaemoglobi- naemia. treatment issues. drug saf ; : - . crossref . kreutz rw, kinni me. life-threatening toxic methemoglobin- emia induced by prilocaine. oral surg oral med oral pathol ; : - . crossref . warren re, van de mark tb, weinberg s. methemoglobinemia induced by high doses of prilocaine. oral surg oral med oral pathol ; : - . crossref . guay j. methemoglobinemia related to local anesthetics: a summary of episodes. anesth analg ; : - . . mansouri a, lurie aa. concise review: methemoglobinemia. am j hematol ; : - . crossref . akıncı e, yüzbaşıoğlu e, aslay s, coşkun f. incidence of meto- clopramide-induced methemoglobinemia. turk j emerg med ; : - . crossref . ryoo s, sohn ch, oh b, kim w, lim k. a case of severe methe- moglobinemia caused by hair dye poisoning. hum exp toxi- col ; : - . crossref . gülgün m, kul m, sarıcı s. prilocaine-induced methemoglo- binemia: report of two cases and review of literature. erciyes tıp dergisi (erciyes medical journal) ; : - . . Öztürk e, aktaş bt, Öztarhan k, adal e. lokal anestezik uygulaması sonrası gelişen methemoglobinemi. jopp rerg ; : - . . aydogan m, toprak dg, turker g, zengin e, arisoy es, go- kalp as. intravenous ascorbic acid treatment in prilocaine- induced methemoglobinemia: report of two cases. [article in turkish] cocuk sagligi ve hastaliklari dergisi ; : - . . den boer pj, bleeker wk, rigter g, agterberg j, stekkinger p, kannegieter lm, et al. intravascular reduction of methemo- globin in plasma of the rat in vivo. biomater artif cells immo- bilization biotechnol ; : - . . ballin a, brown ej, koren g, zipursky a. vitamin c-in- duced erythrocyte damage in premature infants. j pediatr ; : - . crossref . tekbas g, oguzkurt l, ozkan u, gurel k. prilocain-induced methemoglobinemia after endovenous laser ablation. j vasc interv radiol ; : - . crossref kilicli e et al. cost of beauty microsoft word - gebhard - final author version.doc edinburgh research explorer is small still beautiful? citation for published version: gebhard, c , 'is small still beautiful? the case of austria', swiss political science review, vol. , no. , pp. - . https://doi.org/ . /spsr. digital object identifier (doi): . /spsr. link: link to publication record in edinburgh research explorer document version: peer reviewed version published in: swiss political science review publisher rights statement: © gebhard, c. ( ). is small still beautiful?: the case of austria. swiss political science review, ( ), - . . /spsr. general rights copyright for the publications made accessible via the edinburgh research explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. take down policy the university of edinburgh has made every reasonable effort to ensure that edinburgh research explorer content complies with uk legislation. if you believe that the public display of this file breaches copyright please contact openaccess@ed.ac.uk providing details, and we will remove access to the work immediately and investigate your claim. download date: . apr. https://doi.org/ . /spsr. https://doi.org/ . /spsr. https://www.research.ed.ac.uk/portal/en/publications/is-small-still-beautiful( af -e f- e- -f e ae c ).html carmen gebhard is small still beautiful? the case of austria in: swiss political science review, volume , issue , pages – , september . special issue: natural born peacemakers? ideas and identities in foreign policies of small states in western europe. abstract small states are often perceived to be particularly suited to take on the role of mediators and facilitators in international disputes. the case of austria is peculiar in this regard insofar as the emergence of a ‘typical’ small state attitude in international affairs indeed coincided with the establishment of the country as a small nation in . throughout the cold war, austria developed an active and value-based foreign policy which heavily emphasized international law. austrian political leaders, foremost the social democrat bruno kreisky, established a global reputation for their country as a benevolent mediator, for example in the middle east. this attitude has been intrinsically linked to the country’s neutral status, which has been formally preserved until today but has lost much of its substance and practical importance. this paper discusses the historical and normative foundations of austria’s small state identity and asks whether the glorious reputation of the past has been preserved. the paper argues that european and transatlantic integration as well as a number of domestic factors have substantially diminished austria’s role as a ‘natural born’ peacemaker on the global stage. keywords: austria, neutrality, security, small states, internationalism introduction austria is frequently portrayed as a ‘typical’ small state along with, for example, sweden, finland and ireland – both within the european union (eu) and in the wider context of international relations. the title of this article refers to the idea of austrian philosopher leopold kohr ( - ) that greatness was an inherent weakness in states rather than an indicator of their power and superiority over others. while his theory referred more specifically to the societal and economic problems caused by rapid and unlimited growth, his writings also suggested that small states had a greater normative capacity and a greater potential to take adequate policy decisions, to pursue “global pluralistic cooperation” and enjoy “largely unaffiliated self-sufficiency” (kohr : ). by looking at the way austrian foreign policy discourse has developed over time, this article seeks to explore in what way austria tried to play this role of a small and unaffiliated state, and whether any such imagery accurately describes contemporary austria, particularly in view of the country’s involvement in transatlantic and eu security and defence arrangements. within the context of this special issue, this includes the question whether austria is a natural peace-maker, a country with a special disposition towards peaceful means in international relations and with a distinct commitment towards the principles of international law. oliver rathkolb ( : ), a widely published and renowned austrian historian, once referred to post-war austria as the “paradoxical republic” that had spent most of its time being “self-absorbed” and “self-obsessed” regardless of its actual international perception. for him, austrian identity up until the end of the cold war was based on an “overestimation of the austrian question [i.e. austrian independence after ], combined with an unvoiced bad conscience [related to its role in the second world war] that continues to this day, very much as a national solipsism mediated through and strengthened by the austrian press.” in line with holsti ( ), rathkolb points to the importance of national role conception and the issue of identity construction. as this study will show, austrian foreign policy during the cold war was based on visions and ideas that were neither naturally given nor solely induced by external factors. rather it has been austrian political leaders, foremost the social democrat bruno kreisky, who actively established a myth around austria’s ‘third way’ as a neutral country. they promoted austria’s purported normative and moral superiority as an asset in the international sphere, which at the time was dominated by high politics and a conventional balance of power. during the cold war, austria developed an active and value-based foreign policy which heavily emphasized international law. this helped to construct a global reputation for austria as a benevolent mediator, for example in the context of the middle east peace process. however, this was not so much because austria had any sort of natural disposition to play such a role in international relations. rather, the role conception as a peacemaker seemed to serve national interests at the time, while also helping the country to cope with the systemic constraints that the cold war entailed. today, austria is a compliant and inconspicuous post-neutral state whose foreign policy is largely embedded in the european union’s (eu) common foreign and security policy (cfsp). austria’s security strategy of (Österreichische sicherheitsstrategie ) reads very much like a german version of the european security strategy (ess) both in terms of its threat assessment and the perceived political and strategic implications. austria’s neutrality policy, which for decades had been the core of austria’s foreign policy, has lost much of its substance and practical relevance. the reason for this was not only because global circumstances have changed after the end of the cold war. throughout the past two decades, austrian leaders have taken proactive and deliberate steps at reducing the normative significance of neutrality, limiting it to its military core, i.e. the abstention from joining military alliances and from allowing foreign forces to be stationed on austrian territory. this paradigmatic shift gradually undermined austria’s special status as an international mediator. although austria is still not a member of nato it no longer stands for a ‘third way’ in international relations. this article first discusses various theoretical approaches to small state foreign policy and the way they contribute to our understanding of austrian peace policy. it then turns to the development of austrian foreign policy during the cold war, after austrian accession to the eu and in the years following the conservative turn in . the article concludes by looking at the most recent developments in austrian foreign policy and the way these have changed austria’s potential role as a peacemaker. small state austria: smallness as fate or asset? small states have been discussed in the literature as having a distinct approach to foreign policy. in the specific context of the cold war, small state foreign and security policy was seen as being determined by the struggle for physical survival in the context of systemic confrontation between blocks (see rothstein ; keohane ). while this perspective focused on asymmetries in the international system and dilemmas resulting for small states, other studies (e.g. hey ) put more emphasis on small state behaviour, including specific coping strategies. some authors (e.g. inbar and sheffer ; bauwens, clesse and knudsen ; wivel ) have suggested that the awareness of states of their relative size and political and military leverage at the global stage has an impact on the way these countries pursue their foreign policy interests. there is no consensus in the literature as to what exactly constitutes ‘typical’ small state foreign policy along these lines, but hey ( ) identified the following features in small state foreign policy that are commonly discussed in the literature: ( ) a focus on a limited number of core areas in foreign policy (e.g. nuclear non-proliferation, peace-building); ( ) a pre-occupation with securing the immediate geographical neighbourhood; ( ) a commitment towards diplomatic and non-coercive measures; ( ) an emphasis on international law and normative principles; ( ) a preference for multilateral arrangements and international organizations; ( ) and an exceptional readiness to contribute to conflict management and peacemaking. moreover, one of the most common elements of small state foreign policy, particularly during the cold war, was the adoption of neutrality (see e.g. goetschel ), i.e. a status that would keep these states out of military conflicts and other forms of power politics. by adopting neutrality as a foreign policy principle, small states like austria, finland, sweden and switzerland sought to compensate their relative power deficit. instead, they protected their territorial integrity and sovereignty by political and ideological means (katzenstein ). the adoption of neutrality, and more generally, of a small state foreign policy, however, has never just been a matter of small states reacting to the specific challenges they face as weak actors in a global system dominated by great powers. small state foreign policy has also been conditioned by the construction of a specific national identity, which built on the overall awareness of material and structural weakness but also emphasized the promotion of norms and values as a contribution to world order. the result was an approach that went beyond the mere issue of size and relative power gains. many studies on small state foreign policy focus on the way national identities have been constructed around values and ideas that enhanced and perpetuated typical small state foreign policy principles like neutrality or mediation. constructivism generally suggests that any political situation or action has to be interpreted against the background of norms, values and ideas. the ideational and normative context shapes agency in any given situation in international relations. critical constructivists like de cillia, reisigl and wodak ( : ) put emphasis on political discourse and argue that national identities are discursively “produced, reproduced, transformed and destructed”, i.e. they are spoken into existence. based on a set of related emotional attitudes and similar behavioural dispositions they are then “internalized through national socialization”. along these lines, small state identity can be understood as having emerged from a discourse that is informed by perceived smallness but driven by certain political objectives. it becomes part of the mindset of political leaders and the population, and combined with values and other elements of national identity. this small state identity then translates into a national role conception that shapes the state’s international standing. one strand in small state theory underlines that the construction of identity and role conceptions can be used by small states as a strategy to introduce “alternative models of engagement” (ingebritsen : ). the analytical focus is not on the constraints of realpolitik but on the discursive construction of alternatives. thus, taking a strong stance on normative matters and international diplomacy, such as mediation and conflict prevention, enables small states to move the international discourse away from power politics, and find alternative arenas of engagement. during the cold war, adopting foreign and security political profiles that differed from the logic of power politics as it dominated international relations at the time was a viable strategy for small states like austria, finland, sweden and switzerland. it allowed them to compensate their relative lack of conventional political but also military leverage. building on the work of finnemore and sikkink ( ), ingebritsen ( : - ) introduced the concept of small states as ‘norm entrepreneurs’, arguing that international norms have not just “been perpetuated and enforced by those with a preponderance of power” but that they also “originate in a group of states that share distinct ideas about appropriate forms of domestic and international intervention ( - ).” thus, small and neutral states in europe have not only found a way to protect their most vital foreign policy interests, they have also played a crucial role in international norm diffusion, influencing global developments and the way the international community deals with contentious issues. against this background, this article seeks a middle ground between realist and constructivist assumptions. according to a realist perspective small state foreign policy is conditioned by relative limitations in size and resources (e.g. jervis ; wivel ). this includes the contention that the idealistic and peace-oriented ideology often barely results from the awareness of this relative smallness (hey ; goetschel ). the constructivist assumption in turn is that small state leaders have deliberately constructed national role conceptions that would benefit their countries beyond the mere compensation of material weaknesses. the idea of seeking a common ground also resonates in goetschel’s work ( ) as he contends that small states can act as “brokers” for certain ideas and normative visions. he thus combines interest-based arguments with a constructivist perspective. this article holds that the emergence of any sort of small state approach is based on material circumstances and their realist implications but also on the way these are perceived, interpreted and managed by political leaders and their respective societies. in other words, whether or not a state adopts a small state foreign policy approach is both a matter of realist choices, and of the construction and internalisation of an ideational framework that serves specific small state interests. this article is not going to establish whether or not austrian leaders deliberately sought to create a small state identity with the purpose of undermining conventional power politics. it will also not seek to find evidence for rathkolb’s ( ) contention about a “self-obsessed” and “self-absorbed republic”. rather, the article will discuss the way floury rhetorics about a ‘third way’, about the pre-emptive effect of neutrality during peace times (“vorwirkung der neutralität zu friedenszeiten”) and active neutrality policy (“aktive neutralitätspolitik”), have played a powerful role in establishing a distinct international profile for the country during the cold war. what is peculiar about the austrian case is that elites and national media took the idea of smallness and relative weakness to construct a sort of national myth that became engrained in austrian national identity – they turned material inferiority into an asset, “beautiful” in the words of kohr. austria’s role as a peacemaker during the cold war austrian neutrality: peacemaker by choice or by fate? the concept of a “peace policy” (“friedenspolitik”) has never dominated the foreign policy discourse in austria. political leaders have, however, routinely emphasized austria’s disposition to play a distinct role in international affairs both as a mediator and a moral great power. these arguments essentially built on the policy of military non-alignment and neutrality, which austria pursued since the inception of the second republic in . in the course of the cold war, austrian neutrality developed into much more than an international legal status: it was to become the centrepiece of a distinct austrian national identity and national role concept (pelinka ). the extent to which neutrality is a defining part for austria as a nation is not least expressed in the fact that the national holiday is not the day austria regained its independence ( april ), nor the day the second republic was created ( may ). it is the october in commemoration of the adoption of the federal neutrality act (neutralitätsgesetz) in . the idea of establishing a neutral status for austria emerged in the very context of the country being turned into a small state after decades at the heart of a multi-national power block, the austro-hungarian empire ( - ). there is obviously a direct link between the country loosing its great power status and the interest to keep it outside of high politics and hard power issues. however, just as becoming a small state had not been a deliberate choice by austrian leaders at the time, adopting a neutral status for the country was also not a free decision based on any sort of ideological conviction. the following section will look more closely into the specific context of the austrian adoption of neutrality. against this, it then analyses the development of austrian peace policy during the cold war and after . similar to the case of finland and unlike the case of switzerland and sweden, austria’s adoption of neutrality is recent, as it started in the context of the international post-second world war order. the republic of austria was declared permanently neutral (“immerwährend neutral”) in , after the territory had been occupied by allied forces since the end of the second world war. there is evidence (suppan : ), however, that political leaders such as then minister-president heinrich lammasch, catholic conservative, had envisaged neutrality even for the first republic, which was installed in . exponents of both the social democratic party (sozialdemokratische partei Österreichs – spÖ) and the conservative austrian people’s party (christlichsoziale partei) at the time considered this option for austria in order to guarantee its independence and autonomy after the disintegration of the austro-hungarian empire. they only abandoned the idea of a formal declaration of neutrality as austria was granted an international loan under the supervision of the league of nations, and macro-economic conditions put the country into a state of de facto neutrality until . the discourse in austria then started to be dominated by the issue of joining nazi germany to form the greater german reich (grossdeutsches reich), a scenario that eventually materialized when hitler annexed austria in the so- called anschluss (“link-up”) in (stourzh : ). the issue of neutrality was off the table for the duration of the second world war but was revived in the context of the post-war settlements. the austrian state treaty (Österreichischer staatsvertrag) of may marked the re-establishment of an independent and democratic austrian state after the country had been under authoritarian rule from . the treaty built on the moscow memorandum of april in which the soviet union demanded austria to adopt a neutral status based on the model of switzerland (steininger ). this condition was portrayed, particularly by the soviet union, as the only way to ensure stability in central europe in the sensitive post-war setting, where “stability” mainly meant that austria would be kept from joining the transatlantic alliance. the adoption of the permanently neutral status was then formally enacted in the declaration of neutrality (neutralitätserklärung) of october through a constitutional act of parliament (bundesverfassungsgesetz). it seems important to point out that, formally, austria’s declaration of neutrality took place in a unilateral national procedure and out of its “own free will” (“aus freien stücken”) rather than being included in the state treaty, which had been signed by the allied occupying powers, i.e. france, the united kingdom, the united states and the soviet union. this had important legal implications (zielinski : ) since codifying austrian neutrality in the state treaty would have imposed the status, and it would have given the signatories legal power to monitor and enforce the policy. therefore, at least officially, it was the sovereign decision of the newly independent republic of austria to adopt the neutral status. in view of the historical context, however, declaring neutrality was the only way for austria to retain territorial integrity (barz ). the alternative would have been for austria to remain under allied rule, and eventually, to be divided into a western and an eastern part. construction of a national myth: the positive ideologization of an old trauma losing the great power status came as a trauma to the austrian people at the time. post-war austria was a small state with a barely viable economy depending on the support and favour of the world’s great powers. at no time had austrian dependence been more apparent than when the allied powers signed the state treaty on the country’s behalf. it is all the more remarkable that this very moment in history was later reified as a formative event, a historical experience that would define austria’s confident self-image for decades to come (see gebhard ). what is more, instead of taking the adoption of neutrality as what it was, a condition imposed by the allies, political leaders eventually turned neutrality into the centrepiece of austria’s newly gained self-determination (lohninger ), the core of a new role concept that would take the country “out of the shadow of the past” (pelinka ). the position of the two major parties in this process was subject to substantial changes over time, particularly in the first two decades of the second republic. while it was first the conservative Övp to advocate the adoption of a neutral status more strongly throughout the s, this changed in the under the auspices of Övp chancellors although austria’s options were limited by great power interests, at the time, the adoption of the neutrality principle for the second republic seemed to meet the interests of all parties involved. for austria, it constituted a way to re-establish its sovereignty and for the soviet union as well as for the western powers it meant that austria was not going to join any of the two blocks (rendl ). the neutrality act was on the one hand a symbol for the conclusive loss of austria’s great power status but also marked a crucial point in austrian national identity formation. over the next decades, austrian foreign policy discourse saw the construction of a myth (bruckmüller ; liebhart ; kernegger ) around austria’s purported ‘third way’ and the country’s disposition towards a more moral and normatively grounded foreign policy. active and activist foreign policy during the cold war: kreisky’s internationalism austrian foreign policy in the first years of the second republic was understandably inconsistent and confused. austria immediately joined the united nations (un) and the council of europe, showing the importance that austria as a ‘typical’ small state ascribed to international institutions (hey ). in the context of the looming cold war, austrian leaders argued over the way the neutrality act ought to be implemented within the country but even more so in austria’s external relations. conservative chancellors julius raab (four terms in office - in Övp-spÖ coalition governments), alfons gorbach (two terms in office - in Övp-spÖ coalition governments) and josef klaus (one term in office - in Övp-spÖ coalition government, and one term in Övp-government - ) were unclear in their position on neutrality (der spiegel ) although throughout the s it had mainly been the conservative Övp to act as an advocate for neutrality (schneider ). against the background of the creation of the european economic community (eec) in and austrian prospects of potentially joining in the future, there was a tendency within the Övp started to employ a rather loose interpretation of the neutrality principle. its effect should be limited to the military realm and not be extended to other policy areas (meyer ). the same political leaders, however, seemed to be keen to cultivate the myth of the independent and neutral small state because of the pressure they felt from the soviet union. in addition, it would help to distance austria from the german federal republic (brd), and even more so, from the german democratic republic (ddr) (gehler ). it would also work against the memories of hitler’s “link-up” (pelinka : ) and any responsibility (complicity/mitschuld) the austrian people might have had to take in this regard. therefore, the myth of austria as a benevolent small power essentially built on the argument of austria’s victimhood (opferrolle). bruckmüller ( ) contends that neutrality and the positive self-experience it entailed at the time helped austrians to cope with both the loss of international status and the “unvoiced bad conscience”, which rathkolb ( : ) referred to as a core element of austria’s “paradoxical national identity”. to this day, the question of austrian complicity in hitler’s gruesome plan is a contentious issue, with more than % of austrians believing that austria was a victim of nazi-led germany rather than having to share the responsibility (mitschuld) (see e.g. kleine zeitung ). as austria joined the european free trade agreement (efta) in , along with sweden and finland, it was then minister of foreign affairs bruno kreisky (spÖ, - ) who sought to promote a new kind of neutrality policy, which he found should be different from the more passive one practised by switzerland and from the more active approach adopted by sweden (e.g. höll ). his dedication to the issue marked a departure from the reluctance spÖ leaders had shown throughout the s – from this point onwards, it was the spÖ and no longer the Övp to actively promote austria’s neutral status as the core of its international profile. the austrian political culture of the following decades, particularly under later spÖ chancellor kreisky, saw the establishment of a new and increasingly confident self-image, which portrayed austria as the peaceful small state with altruistic intentions, a commitment to building bridges (“brückenbauer”). austria was pictured as a haven for democratic welfare, as the home of confidence and sociability (“souveräne gemütlichkeit”), and as the country of culture and music blessed with a certain moral and intellectual superiority (“moralisch-intellektuelle Überlegenheit”) (bruckmüller : , , ). when kreisky became chancellor in (in office for four consecutive terms, - in spÖ governments) he had already established a track record of active neutrality policy for the country. what conservative foreign minister kurt waldheim ( - ) promoted in preceding years as “active participation in international cooperation” (luif : ) had had less of a distinct focus on the international function of neutrality but was more linked to waldheim’s personal experience within the united nations and related aspirations for a more active role of austria in e.g. the conference on the conference for security and cooperation in europe (csce) (see fischer ). as the figurehead of the spÖ (see pittler ), kreisky was not only at the centre of the social democratic success story of the second republic, he also became something like the “father of the austrian way” in international relations (liebhart : ). kreisky’s engagement within the socialist international was one of the building blocks of his internationalist approach and active if not activist foreign policy. his involvement in major diplomatic actions, particularly in the middle east peace process and in the context of the north-south dialogue, contributed to the establishment of a distinct austrian identity that revolved around the principle of “active neutrality” (“aktive neutralitätspolitik”). one of the most important tendencies in kreisky’s political discourse was the way he glorified neutrality and attempted to establish it as an essential part of the founding myth (gründungsmythos) of an independent austrian state (gehler : ) with the aim of furthering the internalisation of these ideas in the national conscience. austria’s impartiality in the cold war served as a basis for what was to be perceived a distinct kind of foreign policy purportedly driven by a morally higher purpose. under kreisky’s rule, from the late s up to the early s, austrian neutrality was interpreted in an extensive and comprehensive manner. neutrality was not just about the responsibility to be impartial in conflicts, but there was frequent reference in the political discourse to the peace-time effects of the status (“vorwirkungen zu friedenszeiten”). the leaders of the spÖ, in particular, promoted a conception of neutrality that went well beyond the limited military meaning of the term and was to include all parts of civic life. as mentioned before, rathkolb ( : ) suggested that kreisky was, for example, prominently involved in the international discourse in reaction to the jom kippur war in october . he openly argued for europe to take on an active role in bringing peace to the middle east. throughout - , he led a number of fact-finding missions to facilitate negotiations between israel and various arab states. in , he was one of the first western leaders to reach out to jassir arafat for diplomatic contact (see secher ). during his terms as foreign minister and chancellor, kreisky actively sought contact with leaders in the developing world. in , he organized a north-south summit in cancun to facilitate debate between what were then the first and the third world (see rathkolb ). kreisky’s offensive style in foreign policy matters, however, was interpreted by some (pelinka and rosenberger ) as an attitude that would endanger austria’s impartiality rather than actually building on it. for a discussion on the way these peace-time effects have been reinterpreted over time, see luif ( - ). this approach assumed traits of a “self-obsession” at times, which came inflated conceptions about austria’s capacity to make a difference in world politics. it was in these years that austria developed a significant peace policy. vienna hosted a set of important international events (gustenau ) such as the strategic arms limitation talks (salt) - and the conference for security and cooperation in europe (csce) in . austrian diplomat kurt waldheim served as un secretary general for two consecutive terms ( - ). also, the headquarters of international organizations were established in vienna, for example the organization of petroleum exporting countries (opec) in , and the un in . under the conservative chancellor raab ( - ) the headquarters of the international atomic energy community (iaea) had already been established in vienna in . austria also deployed soldiers in un peacekeeping operations, first in the congo in , then in in cyprus, and from until june on the golan heights bordering syria and israel, as part of the un disengagement observer force. this international engagement did bring external recognition but it also enjoyed broad domestic support as it “allowed the austrian people to some extent to overlook that their country was no longer one of europe’s leading powers” (meyer : ). austria’s post-cold war peace policy after kreisky: active but no longer activist during the mid and late s when bruno kreisky was succeeded by spÖ chancellor fred sinowatz (one term in office - , spÖ-freedom party/fpÖ coalition government) and then franz vranitzky (spÖ, four terms in office - , one term in coalition government with fpÖ, three terms with Övp) austrian neutrality policy became more low-key. the spÖ retained the ministry of foreign affairs until and to some extent continued an “active policy of neutrality”. eventually, however, kreisky’s commitment towards a “global foreign policy” was to be eclipsed (luif ). the most important changes in this respect were introduced by alois mock, conservative vice chancellor ( - ) and foreign minister ( - ), as he started to bring austria closer to the european project. in , he pushed for an open debate about austria’s future role in international relations. he underlined that austrian foreign policy had been determined by global circumstances, i.e. the context of the cold war. any change to these circumstances as it happened would require a rethinking of austria’s foreign policy principles including neutrality (scheich ). mock’s term in office therefore marked a period in austrian foreign policy that was dominated by the attempt to normalize austria’s status in international affairs, and to move away from the idea of a ‘third way’ or austrian exceptionalism. the discourse on neutrality was significantly toned down as representatives of the conservative Övp seemed to prepare the public for a historical step: the formal application for accession to the then european economic community (eec). one of the main issues in this regard was whether austria’s neutral status was compatible with full membership in the eec. mock managed to diffuse concerns about the country losing its independence by pointing to the importance of “real” rather than “formal sovereignty” (scheich : ). in a changing international environment and in the face of economic recession, austria’s ability to act autonomously was intrinsically linked to its involvement in significant decision-making bodies, i.e. also in the eec’s institutions. when austria formally applied for eec membership in there was a general perception among austrians that neutrality could be retained regardless. at the european level, austria’s legacy as a neutral country was seen as a useful contribution to the peaceful integration of western europe (luif a). moreover, ireland had already set an example when it joined the eec in retaining its status as a neutral and non-aligned country. at the point of application, the austrian coalition government (upon the insistence of the spÖ) included a reserve condition (“neutralitätsvorbehalt”) that would allow the country to formally retain its neutral status regardless of any potential involvement in political integration, i.e. the so-called “irish clause” (gehler : ). however, in the austrian case no such reserve was brought up during the accession talks, which took place after the treaty on european union, which included a foreign and security policy component, had become the new legal basis for membership. the austrian public seemed unimpressed by this change as the following eu referendum in june resulted in a clear . % in favour of accession. when austria, sweden and finland joined the eu they indeed signed an additional protocol to declare that they would pursue european policies without any reservations that might arise from their foreign policy status (schneider ). european union membership and transatlantic integration when austria became a member in , the eec had developed into a political union, which included a common foreign and security policy (cfsp). although the security and defence component of the cfsp did not materialize until the early s, austria had subscribed to all parts of the policy, which according to title v of the treaty of maastricht of (treaty in european union, maastricht) foresaw the creation of a common security and defence policy if the council so decided. in , shortly before austria joined the eu, a special provision was added to the austrian federal constitution (article f) to make sure that austrian participation would not clash with legal responsibilities related to the neutrality act of (bundesgesetzblatt ). this meant a clear change of direction in austria’s foreign policy: neutrality was formally reduced to the core of military impartiality, whereas austria’s contribution to european integration constituted the new building block of its new peace policy. although neutrality was still an essential element in austrian national identity, public interest in these changes remained limited, particularly as the discourse within the eu still highlighted similar themes, such as solidarity and civilian security. austria also joined the nato partnership for peace (pfp) and its planning and review process (parp) in , alongside finland and sweden, without any major domestic controversy. the international context of nato revising its strategic outlook and self-image in view of the new global circumstances after the end of the cold war certainly helped to diffuse concerns that pfp-membership could endanger austria’s independence. if at all, the pfp programme was publicly debated as a platform for technical cooperation and development with minor political implications. any option of joining the alliance as a full member, however, continued to be ruled out. moreover, in , austria was one of the founding members of the un multinational standby high readiness brigade of un operations (shirbrig) and has since contributed to shirbrig with a contingent consisting of a transportation company as well as taking over its presidency in . austria’s early years as a member in the eu and full contributor to the eu’s cfsp were in no way compromised by the neutrality issue. the discourse at the international and european level in fact moved away from austria’s special status altogether. instead, political leaders, and most of all representatives of the Övp, seemed keen to underline their new focus on the principle of solidarity, and to the brigade ceased operational business in june . signalise that austria was not going to obstruct any steps towards further european integration (schneider ). the eu’s security and defence policy, and the military capability development process were eventually brought underway during the austrian council presidency in the second half of . the foreign minister to succeed mock in , wolfgang schüssel (Övp), was one of the central figures in the new domestic debate about the changing importance of neutrality for austria’s role in the world. while at the beginning of austria’s eu membership he was still moderate in his views about the compatibility of neutrality with european integration, his perspective changed dramatically over time. in public statements he started to picture permanent neutrality as a status that had been imposed upon austria in a very specific historical context, namely in return for the withdrawal of post-war soviet occupation forces. schüssel openly declared that neutrality would no longer make sense in the complex circumstances of the st century (nationalrat ). president thomas klestil ( - ) in turn adopted a moderate position, which did not openly challenge schüssel’s basic argument but highlighted that formally speaking the austrian parliament had adopted neutrality out of its own will. he also stressed that any changes to the existing status of austria would need to be approved by the austrian population. however, klestil ( ) himself also suggested that austria’s neutrality policy would need to be reinterpreted as international circumstances had changed. he underlined that neutrality had never been an end in itself and that securing the country’s interest should be the foremost priority of any approach to international engagement (schneider ). outlining schüssel’s evolution during these years, pelinka ( : ) pointed out that the argumentative challenge for politicians was enormous: “now the elites had to undo the belief they had worked on long and hard to install in the austrian people”. finding common ground in the face of this challenge, and agreeing on a joint course for a new austrian foreign policy after the end of the cold war and in the new european context, turned out to be impossible for the two governing parties, the spÖ with chancellor viktor klima ( - ) and the Övp with vice chancellor and foreign minister schüssel. in , internal divisions over this issue along with fundamental disagreements over economic and social policy ended the phase of grand coalition governments ( - ) as well as social democratic prevalence. after the general elections in , spÖ and Övp failed to build another coalition government, so that schüssel turned to a coalition with the far-right freedom party (fpÖ), which had won a landslide victory equalling the Övp at . % in the parliamentary elections. the emerging Övp-fpÖ government was the first centre-right coalition in the history of the second republic – a systemic change, which had fundamental implications for austria’s foreign policy. the conservative turn in at the european level this ‘conservative turn’, i.e. the inclusion of jörg haider’s fpÖ in the government, was seen as a threat to liberal democracy, which is why the then eu- decided to impose diplomatic sanctions on austria. at a time Övp chief schüssel wanted to see his country as an integral part of the european integration project, austria found itself more isolated than ever since the establishment of the second republic. although the sanctions were eventually lifted, a bad aftertaste remained. in the following months, schüssel’s Övp advocated a strong pro- european stance for his country, underlining the principle of intra-european solidarity. no longer restricted by normative concerns of the former coalition partner some argue (e.g. luif ) that austria struggles to this day to find allies within the european union. spÖ, now chancellor schüssel ( - ) adopted a clear yet rather drastic approach to the issue of neutrality and austrian exceptionalism. in a number of public appearances he emphasized that the circumstances under which neutrality had been deemed necessary or useful in the past had ceased to exist with the fall of the soviet union and the end of the cold war. in fact, since austria had become a member of the eu “it had no longer been capable of being neutral in practice anyway. […] we will have to finally tell people the truth” (nationalrat ). it was also schüssel who in a speech to the national assembly on the th anniversary of the austrian neutrality act ( october , national holiday) explained austrian emotional and ideological attachment to neutrality as similar to the one to “lipizzaner” and “mozartkugeln”, which had also lost much of their normative importance but would continue to exist in people’s minds (nationalrat ). aware of public support for neutrality (see e.g. reinprecht and latcheva : ), however, he added that the core of the policy would be retained: austria would still not fight wars, host any foreign troops on its territory or become a member of any military alliance. in , the national assembly adopted a new security and defence doctrine (Österreichische sicherheits- und verteidigungsdoktrin ) after the last defence plan had dated from and was based on the defence doctrine of . the new document also suggested that austrian neutrality had de facto changed in the course of eu accession, and that the status was now rather “non-aligned” (“bündnisfrei”), which reflected a narrative that sweden (“alliansfri”) and finland (“sitoutumattomat“) had taken on already in the early s in view of eu accession. ‘neutrality’ was to be replaced with ‘solidarity’. the document also contained strong “lipizzaner” are a breed of horse, which is closely associated with the spanish riding school (hofreitschule) in vienna. “mozartkugeln” is a confectionary, which has for a long time been exclusively produced in salzburg. references to the objectives of the eu’s foreign and security policy, suggesting i.a. that austrian security could no longer be seen in isolation from the eu context (hauser ). in other words, neutrality had been dismantled insofar as austria’s foreign policy would no longer differ from that of other member states. in meanwhile, the government also started a major reform of the armed forces in line with the capability development processes austria absolved in the context of nato’s parp and the eu’s capability action plan (ecap). austria’s involvement in these developments was at no point compromised by reservations concerning the continued status of formal neutrality. meanwhile, the reform was as much a strategic decision in view of new global circumstances as a political and financial necessity: the only constraints for austria’s armed forces in this regard seem to have been the obvious budgetary limitations (with a general defence budget of less than . % of the gdp), and the relative pressure to be interoperable within the eu and nato-pfp frameworks. when the eu’s european security and defence policy (esdp, now csdp) became operational with the launch of the military operation ‘concordia’ in the former yugoslav republic of macedonia in march , austria contributed with a contingent, along with other formerly neutral member states such as sweden, as well as france, germany, italy, spain, portugal and ireland. in the years to follow, austria became one of the top- esdp contributors with consistent contributions of up to % (sipri ). the largest and most extensive involvement of austrian forces in other countries in this top- list are france, italy, germany, spain, the united kingdom, poland, the netherlands, (austria) hungary and portugal, which shows that austria’s contribution is remarkable for a state of its size and capabilities. an eu operation has so far been in the context of eufor ‘althea’ in bosnia and herzegovina with approximately troops at a time (since ). recent developments since the end of the centre-right coalition in and the return to power of an spÖ- led coalition with the Övp, austria has moved further away from its exceptionalism. even under the social democratic chancellor gusenbauer (spÖ), neutrality and the myth of austria’s ‘third way’ did not see its revival. austria has since continued its path towards a normalized and inconspicuous national role conception, and has pursued a policy of ‘pragmatic neutrality’, albeit without turning into a free rider. the austrian security strategy (Österreichische sicherheitsstrategie ) has by now fully endorsed the eu approach to contemporary challenges as it was laid down in the european security strategy in although it is still awaiting ratification. austrian forces have been deployed in most civilian and military csdp missions and some nato-led operations over the past years. these contributions seemed to be more restricted by material shortfalls and budgetary restraints than by political reservations. critical voices have repeatedly pointed at austria’s reluctance to deploy forces in more robust operations such as in afghanistan where austrian contributions have been limited. crucial in this debate have been internal documents of the us embassy in vienna, which were made public by wikileaks in late (cable state ). these documents criticised austrian leaders, and minister of defence norbert darabos in particular, for being “openly hostile” to committing since , austria has contributed even larger contingents of up to troops to the nato-led kfor in kosovo. since , austria has also held a contingent of up to troops with undof on the golan heights (syria/israel). troops to dangerous operations such as in afghanistan and iraq (presse ). while austrian contributions in these cases have indeed been limited, there has generally been a clear move away from traditional limitations in the scope of operational engagements. this was not least marked by the austrian participation in the (then) eu-led civil-military operation in chad ( - ), which was both unpopular and militarily challenging. while during the cold war any international engagement of austrian forces was to be limited to non-controversial types of missions such as un peacekeeping operations and monitoring, austria is now more ready to deliver across the whole spectrum of petersberg tasks. austria also contributes to a multi-national battle group along with germany, the czech republic, croatia and macedonia. most recently, in spring , the austrian contingent at undof, which has been stationed on the golan heights since , saw a dramatic change of operational and strategic circumstances. as the civil war in syria unfolds, un forces stationed near the border are expected to “interpret their mandate more extensively”, i.e. including the use of weapons to enforce un law. in the past, the austrian government would have considered withdrawing its troops to prevent them from getting involved in fighting. this time, however, acting defence minister darabos (spÖ) is simply expressing “concerns” while the austrian commander orders “business as usual” (kurier ). in the context of recent treaty revisions, and the incremental extension of the remit of the eu’s cfsp and csdp, austria has refrained from claiming any sort of special treatment. while drawing up a new framework for the eu’s csdp operations as well as for the internal and external dimensions of its general security policy, the reform treaty of foresaw both a solidarity clause (“solidaritätsklausel”, art. tfeu), petersberg tasks also include more robust scenarios, such as peacemaking and the separation of parties by force. and a mutual military assistance clause (“beistandsverpflichtung”, art. teu) (see schilchegger ). the treaty thus contained a number of legal provisions that further reduced the substance of austria’s neutral status, although these came with a number of caveats that left the question what an assistance or solidarity call would practically entail for austria, relatively open. it is important to point out, however, that these provisions came with a number of caveats. the section on the common security and defence policy (art, teu) i.a. highlights that the policy of the union “shall not prejudice the specific character of the security and defence policy of certain member states” (art. ( )). this so-called “irish clause” has traditionally served as a safeguard for neutral member states to ensure their participation in eu policies does not interfere with legal obligations arising from their status. legal experts have been divided as to whether this would mean that neutrals would as a result be bound by a kind of “asymmetric” assistance clause, which would only come with benefits for these states but with no responsibilities. others have highlighted that art. ( ) on the military assistance clause would have had to repeat this safeguard whereas it only mentions member state obligations towards nato in this context. hilpold ( ) summarizes the legal debate by suggesting that any specific commitment or even involvement of austria would be decided on a case-by-case basis. what seems crucial, in any case, is that regardless of these novel legal implications the neutrality principle has been formally retained to this day. according to several public opinion polls conducted in the past decade, austrian citizens consider neutrality an essential part of their national identity. today, however, austrian neutrality is reduced to its core meaning, i.e. no membership in any military alliance (i.e. nato) and no stationing of foreign troops on austrian territory. any additional meaning and normative effect that neutrality was ascribed during the cold war has been replaced by a policy of active but not activist engagement within the eu and nato’s pfp. full-nato membership has so far still not been envisaged, not least because public support for such a step is limited (reinprecht and latcheva : - ). according to opinion polls held during the past decade more than % of austrians would not approve of formally giving up neutrality, which is what nato-accession would entail. the ideological and societal costs of such a step are higher than the relative gains as austria is already fully associated in the transatlantic context of the pfp. a majority of the austrian population is also in favour of common european security and defence arrangements including the capability improvement processes coordinated through nato’s parp, although overall support for the eu has been consistently low among the austrian people. conclusion: not a natural born peacemaker this article set out to explore in what way austria has followed a typical small state approach in its foreign policy, and to what extent the end of the cold war as well as austria’s involvement in transatlantic and eu security and defence arrangements have had an impact on the country’s national role conception. in the context of bipolar confrontation, austrian leaders, and foremost the social democrat bruno kreisky, actively sought to establish a global reputation for their country as a benevolent mediator, and purportedly, a ‘natural born’ peace maker. much of this normative image built on austria’s neutrality, which allowed the country to promote an alternative ‘third way’ in its foreign policy. kreisky’s diplomatic activism during the s and s helped the country to assert itself on the global stage despite its relative lack of resources and leverage. today, much of the discourse about the normative orientation of austrian foreign and security policy has been retained, but policies and the underlying constitutional law have gradually changed in substance. austria’s accession to the eu and its contribution to the csdp have normalized the country’s international profile. even if austria has so far refrained from abandoning its neutral status altogether by e.g. entering nato as a full member, the country is externally perceived as part of the eu and thus as part of an alliance that is based on mutual solidarity. over the last decade, the eu has become more involved in all policy areas, and the implications of membership are far more comprehensive than they were at the time austria entered the union in . austria, regardless of which parties constituted its government, has established itself as a proactive eu member state that consistently pushes for closer cooperation in all policy areas including sensitive policies like security and defence. geostrategic circumstances after the end of the cold war have exposed neutral countries like austria to a new set of challenges, which could not be addressed by military or hard power alone. contemporary threats such as organised crime, religious fundamentalism and transnational terrorism do not lie within the remit of an active neutrality policy. potential attacks are no longer directed against states with certain international positions but against western civilization as a whole. this includes neutral states as much as any one of the great powers with offensive foreign and security policy traditions. moreover, globalization has deprived austria of the option to argue for a special status as a proponent of the third way or as a natural born peace maker, and finding partners and political allies in europe has proven difficult as well. finally, this article also set out to explore whether austria has got a special disposition towards peaceful means in international relations, i.e. whether it has been a ‘natural born’ peace maker. in answering this question, this article sought a middle ground between realist and constructivist explanations of small state behaviour in international affairs. the conclusion here is that austria has in fact never been a natural born peace maker. as has been reflected in the level of moral inflation and self-obsession over austrian exceptionality during the cold war, it was not really a natural decision of the country to be “small and beautiful”. adopting a sort of non- offensive but active (and activist) foreign policy during the cold war was more of a strategic decision than a normative one. reduced to a small state, and in the shadow of the all-pervasive block confrontation, there was very limited leeway for an autonomous foreign policy profile. austrian leaders, however, successfully established an image of austria as an ideal partner and mediator in conflict situations. as soon as systemic circumstances allowed for fundamental changes, leaders moved away from the idea of a ‘third way’, which proves to an extent that the peace policy had been a mere strategy to survive. austria’s peace policy, however, was more than just a product of historical circumstances as a structuralist perspective would suggest. as this article has shown, austrian leaders constructed a specific image for austria to be able to make the most out of its relatively weak position at the time. bibliography barz, a. 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this scattering is based on dipole-dipole (d-d also called e e ) transition process, which depends on only x-ray polariza- tion vectors. in higher order approximations, the resonant scattering also depends on x-raywavevectors; the scatteringprocess canbequadrupole-quadrupole (q-q,e e ), dipole-quadrupole (d-q,e e ), etc.thequadrupole effect is generally small compared with the d-d scattering but it can be observed in practice. near k-absorption edge, according to selection rules for electronic orbitals, we can detect p-like states from the dipole transition, d-like states from the quadrupole transition and p-d hybridization of states from the d-q transition. templeton and templeton [ ] observed x-ray linear dichroism by synchrotron ra- diation experimentandpetcovet al. [ ] observedbirefringenceaswell as thedichroism with a technique like visible-light experiment. in , templeton and templeton [ ] observed also nonforbidden reflections intensities dependent on x-ray polarization and supposed that a special type of forbidden reflections can be excited owing to the polarization anisotropy. this polarization effect is caused by electric anisotropy of resonant atoms near the absorption edge. from these results it was pointed [ , ] out that the atomic scattering factor should be treated as tensor and traditional extinction rules for bragg reflections were violated. in practice the forbidden reflec- tions were observed in many crystals, first by templeton and templeton [ , ], kirfel et al. [ ] and then by many other groups. even in cubic crystals the polarization anisotropy was observed with diffraction method [ , ]. in most cases, the observed azimuth dependence of the reflections was explained by the dipole approximation, e.g. in nabro [ , ], cu o, tio [ ], fes [ ], fe o [ ], hofe [ ], etc. in iron pyrite, fes , the polarization anomaly of the forbidden reflections was directly stud- ied with polarization analysis [ ], and its property was also explained in the dipole approximation. however, the forbidden reflections that are not allowed in dipole approximation were observed in some crystals. finkelstein et al. [ ] investigated the forbidden rhombohedral reflection in hematite, α-fe o , near the fe k-absorption edge. the azimuthal dependence of the reflection was found to be sixfold, which was explained by q-q scattering. templeton and templeton [ ] observed forbidden reflections in germanium crystal near the ge k-edge at room temperature. their properties were explained by d-q scattering. after that time kirfel et al. [ ] found d-q scattering in addition to d-d scattering from magnetite, fe o , near the fe k-edge. kokubun et al. [ ] measured the detailed energy spectra of the forbidden reflections in iron resonant elastic x-ray scattering in condensed matter pyrite. as a result different spectra were carefully examined in the pre-edge region of the fe atom and their azimuthal dependence was explained by the d-d and q-q scattering combination [ ]. similar quadrupole effects were also reported in other crystals: spinel ferrites [ – ], tio [ ], etc. considering the physics of forbidden reflection, a new type of anisotropic reso- nant scattering that is induced by atomic thermal motion was predicted [ , ]. in germanium crystal, the forbidden reflection was indeed strongly dependent on tem- perature and this result revealed that the large part of the intensity was caused by thermal-motion-induced (tmi) resonant scattering [ ]. thege atoms are in regular tetrahedral symmetry, but the atomic displacement from the equilibriumposition de- grades the symmetry. therefore thermal motion allows us to observe the anisotropic d-d scattering despite of high average site symmetry. the tmi scattering is mainly caused by the effect of optical phonon mode and additionally reflects thermal motion correlations. other physical problems solved with the help of the resonant forbidden reflections are discussed in sect. . in this paper we introduce typical and remarkable experimental results on the forbidden reflections caused by the resonant anisotropy. we show also additional and complicated physical phenomena concerning resonant scattering, in particular, we consider the influence of the magnetic scattering, thermal motion and so on. it is demonstrated that the quadrupole scattering effect is typical of many crystals. basic theory according to the second-order perturbation theory of interaction betweenphoton and electronic states, the anomalous scattering factor near the absorption edge is given by fres = m ∑ n 〈a |(ε′ ·p)e−ik′·r |n〉〈n |(ε ·p)eik·r |a〉 ea − en +�ω− iΓn/ , ( ) where ε and k represent the polarization and the wave vector of incident x-rays, and ε′ and k′ those of scattered x-rays, respectively. equation ( ) has a resonant denominator for x-ray energy �ω from the ground state |a〉 of energy ea to interme- diate states |n〉 of energy en and width Γn. by expanding the exponential factor in eq. ( ), we obtain the approximation of the power series, eik·r ≈ + ik ·r. ( ) therefore, the atomic scattering factor containing non-resonant terms for the i-th atom in the unit cell can be expanded in a series over the wave vectors k and k′ : (f̂i)jk = f i δjk +(f̂ dd i )jk + i(f̂ dqs i )jkl(kl −k′l) +i(f̂ dqa i )jkl(kl +k ′ l)+(f̂ qq i )jklmklk ′ m +(f̂ mag i )jk, ( ) where f i is the conventional thomson scattering factor given by a scalar quantity, f̂ddi and f̂ qq i describe dipole-dipole (d-d) and quadrupole-quadrupole (q-q) scattering whereas (f̂ dqs i )jkl = (f̂ dqs i )kjl and (f̂ dqa i )jkl = −(f̂dqai )kjl correspond to symmetric and antisymmetric (relative to the first two indices) contributions to mixed dipole- quadrupole (d-q) scattering, and f̂ mag i stands for magnetic scattering, which should be added in the case of magnetic material. the d-d scattering factor is the tensor of second rank, the d-q factors of third rank and the q-q factor of fourth rank [ – ]. the european physical journal special topics using the tensorial scattering factor f̂i, the tensorial crystal structure factor is given by f̂(g)= ∑ i f̂ie − πig·ri, ( ) where g is the scattering vector and ri is the atomic coordinate of the i-th atom in the unit cell; the tensors f̂i of crystallographically equivalent atoms are related by the space-group operations. the scattering matrix for the × format of a structure factor f̂ is described as m̂ = ( mσ′σ mσ′π mπ′σ mπ′π ) = ( σ′ f̂ σ σ′ f̂ π π′ f̂ σ π′ f̂ π ) , ( ) and the total scattering intensity, i, for the σ-polarized incident x-rays is given by i = iσ′ + iπ′ = |mσ′σ| + |mπ′σ| , ( ) where σ and π represent the two polarization vectors of incident x-rays, and σ′ and π′ those of scattered x-rays, respectively. experimental in this paper we treat mainly compounds of d transition metals near their k-absorption edges. our synchrotron radiation experiments were mainly performed with a four-circle diffractometer installed on beam line c at photon factory, kek in tsukuba, japan. the incident x-ray energy was selected with a double si ( ) monochromator which was detuned to about % intensity yield in order to exclude higher harmonic components. we used a reflection plane that is parallel to surface of the studied single crystal. the samples were mounted on the diffractometer with measured reflection plane perpendicular to ϕ axis of the diffractometer. on this condition we can easily make azimuthal angle scanning. we set additionally a polarization analyzer on θ arm of the diffractometer if we need polarization analysis of the scattered x-rays. the other experimental arrangements were typical of a diffraction experiment with synchrotron radiation. since the polarization of the incident x-rays was in the horizontal plane and the scattering plane was vertical, the incident beam was σ polarized. the energy dependence and the azimuth dependence of the forbidden reflections were obtained from integrated intensity with θ– θ scan. of course, we subtract the background intensity from the scan. here we must take care of contribution of renninger re- flections (multiple-wave peaks), which are excited via nonforbidden reflections and observed in the azimuthal scanning. we first measured the renninger plot and made azimuthal correction by comparing with the calculation. then we searched flat po- sitions between those peaks and selected carefully the azimuthal angles to avoid the renninger effect at each energy. this procedure allows us to obtain smooth datawith the intrinsic symmetry. results and discussion we first present a simple structure case, iron pyrite fes [ , , ], which is a cubic crystal with the space group pa ̄. the iron atoms occupy the fcc positions and the site symmetry is ̄. in this symmetry the d-d and q-q scattering are allowed, but resonant elastic x-ray scattering in condensed matter . . . . . . . . energy [kev] in te ns it y [a rb . u ni ts ] fes absorption (a) . . . . - . - . s ca tt er in g fa ct or [ el ec tr on s/ at om ] . . . . . . energy [kev] scattering factor real part imaginary part (b) fig. . observed energy spectra in iron pyrite, fes , near thefek-absorption edge: (a) the absorption coefficient and forbidden reflections intensities [ ]; (b) the real and imaginary parts of the anisotropic tensor element of the iron scattering factor [ ]. the d-q scattering is not allowed by inversion symmetry. we need only one complex parameter (the difference of atomic x-ray susceptibilities along and perpendicular to the corresponding threefold axis) to explain the d-d forbidden reflections intensities in iron pyrite [ ]. figure (a) shows the observed energy spectra of the forbidden reflec- tions intensities near the fe k-absorption edge. the absorption data were measured in advance by usual xafs technique with a powder sample. in order to distinguish the scattering character, d-d or q-q scattering, we must perform the azimuthal scan- ning or more complicated measurement, e.g. polarization analysis. above the edge, the shapes of energy spectra are almost the same as shown in fig. (a). the azimuth dependence well agrees with the calculation of d-d scattering at the energies above the edge [ , ]. the results of polarization analysis of the scattering x-rays are also in good agreement with the dipole calculation [ ]. therefore we conclude that the reflections above the edge are caused by the d-d scattering from p-like states. the derived scattering factor depicted in fig. (b) is discussed later. in the pre-edge region, on the other hand, the shape of the energy spectrum is different from each other as shown in fig. (a). even for the same reflection, spectra change with azimuth angle. these results indicate that other contributions in addi- tion to the d-d scattering factor are involved in the scattering. in fact the azimuth the european physical journal special topics in te ns it y [a rb . u ni ts ] . . . . . . energy [kev] fes ϕ = . ϕ = . fes ϕ = . (a) in te ns it y [a rb . u ni ts ] azimuthal angle [degree] obs. . [kev] calc. (d-d) calc. (q-q with d-d) (b) fes fig. . forbidden reflections intensities in the fe pre-edge region of fes . (a) observed energy spectra of the and forbidden reflections at different azimuthal angles, ϕ. (b) azimuthal angle dependence of the reflection. the dashed curve in (b) is calculated based on the d-d scattering.the solid curve denotes the d-d and q-qmixed calculation. (the observed and data are the same as in references [ ] and [ ], respectively.) dependencewell agreeswith the calculation of d-d and q-qmixed scattering as shown in fig. (b). therefore we conclude that the scattering in the pre-edge region has d-d and q-q mixed character. similar situation is also seen in tetragonal rutile crystal, tio [ , ]. the d-d and q-q scattering is also allowed in the crystal. above the ti k edge the character of the forbidden reflections is explained by the d-d scattering. in the pre-edge region, however, the energy spectra show different profiles and the azimuth dependence is quite different from the d-d calculation [ ]. figure shows the azimuth dependences of the forbidden reflection at two energies above and below the edge. the azimuth dependence at the lowest resonant energy nearly coincides with the q-q calculation. thus in the pre-edge region of the d transition metals the q-q scattering is large in comparison with the d-d scattering. inmagnetite, fe o [ , , , , , ], the fe atoms occupy two different sites, tetrahedral and octahedral sites. in this case the scattering conditions at the sites are resonant elastic x-ray scattering in condensed matter in te ns it y [a rb . u ni ts ] azimuthal angle [degree] obs. . [kev] . [kev] calc. (d-d) calc. (q-q) calc. (q-q with d-d) rutile tio fig. . observed azimuthal angle dependence of the forbidden reflection intensity in rutile, tio , above the ti k-absorption edge ( . [ev]) and at the lowest resonant en- ergy ( . [ev]) in the pre-edge region. the curves denote the d-d and/or q-q scattering calculations. (all observed data are the same as in ref. [ ].) n or m al iz ed i nt en si ty . . . . . . energy (kev) fe o d-d dominant d-q dominant absorption fig. . energy spectra of the forbidden reflection intensity in fe o near the fe k- absorption edge with polarization analyzer. circles and squares were observed on special experimental conditions, fixed azimuthal angles and polarization angles. circles (squares) are on the conditions where the d-q (d-d) scattering almost vanishes. (all data are not published before, though the tentative results are in ref. [ ].) rather complicated.because of symmetry restrictions, for the tetrahedral site onlyd-q scattering gives contribution to forbidden reflections, whereas d-d and q-q scatterings (and not d-q) are allowed from the octahedral site. in the forbidden reflection exper- iment both the d-d and the d-q scatterings have been observed near the fe k edge though evidence of the q-q scattering is absent until now. it is generally difficult to measure separately different characters of the scattering. however the experimental conditions for their observations are different. by selecting the appropriate reflection plane and azimuthal angle and using polarization analyzerwe canmeasure separately the d-d or d-q scattering frommagnetite [ ]. the observed energy spectra are shown in fig. . the one of them (squares) shows the d-q scattering from almost hybridized p-d mixed states of the tetrahedral site. another spectrum (circles) shows the d-d scattering from almost p-like states of the octahedral site. for the energy spectra of the anisotropic d-d scattering we measured three crys- tals. figure shows the observed energy spectra of iron, cobalt and nickel pyrites, fes , cos , nis [ ], which have the same pyrite structure. as shown in this the european physical journal special topics n or m al iz ed i nt en si ty - energy [ev] fes cos nis fig. . energy spectra of the forbidden reflection intensities in three pyrite crystals, fes , cos , nis (same data as in ref. [ ]). the origin of the energy scale denotes each metal k-absorption edge. figure the similar spectra are observed from the similar crystals above the metals k-absorption edges. the reason may be that in high-energy region the spectra are mainly determined by surrounding sulfur atoms, because allmetal ions have the same divalent states. in addition to the anisotropic scattering intensity we can measure the phase of the scattering factor. when allowed multiple bragg reflections are excited simulta- neously with forbidden reflections, the strong renninger peaks are observed in the azimuthal scanning of the forbidden reflection. the renninger scattering amplitude has opposite phase in each side of the reflection peak, therefore the interference effect with the anisotropic scattering is different in each side. by means of the interference we can determine the phase of anisotropic scattering factor because the amplitude of the renninger reflection can be calculated if the crystal structure is known. using this technique we can obtain separately the real and imaginary parts of the atomic scattering factor, i.e. two separate energy spectra. for details of the multiple-wave interference theory for forbidden reflections and the phase determina- tion method, see references [ ] and [ ] respectively (see also [ – ] and references therein). figure (b) shows the successfully obtained energy spectra of real and imag- inary parts of the iron pyrite scattering factor. the observed spectra are supported by the electronic states calculations with muffin-tin and full potential approach. the refined calculated spectra are in good agreement with the observation [ ]. the sep- arately obtained real and imaginary spectra could be very useful for studying the details of the electronic states. this is more informative than only the intensity data. we next take a rare case, anatase crystal [ ], where the resonant scattering from only p-d hybridized orbitals with different parity can be observed. anatase is a tetragonal polymorph of tio , the ti site symmetry is ̄m . in the crystal, all d-d and q-q atomic scattering factors of ti atoms are exactly the same. therefore, in the forbidden reflections, we can observe only the d-q scattering. in this case two parameters are needed for the forbidden reflection. figure shows the observed energy spectra of the reflection intensity. the shapes of the two spectra are almost identical at different temperatures. the shapes of azimuth dependences were also not changed by temperature. a little intensity increase was observed down to k from roomtemperature (inset infig. ), but the temperature dependence canbe explained by usual debye-waller factor. therefore we conclude that the observed anisotropic resonant scattering is almost pure d-q scattering induced by p-d hybridization of or- bitals. this result is quite different from that in germanium crystal, which is largely resonant elastic x-ray scattering in condensed matter n or m al iz ed i nt en si ty . . . . . . . . . energy (kev) k k absorption anatase tio in te ns it y (a rb . u ni ts ) temperature (k) fig. .energy spectra of the anatase forbidden reflection intensitymeasuredatdifferent temperatures near the ti k-absorption edge. the spectra are normalized to a common maximum intensity. the inset shows the temperature dependence at the peak-top energy. (all data are the same as in ref. [ ].) dependent on temperature, see below. a possible physical reason of this difference is that in anatase, contrary to germanium, the main contribution arises from the anti- symmetric d-q term which cannot be induced by thermal motion of atoms. in spite of the same chemical formula, tio , the property of the anisotropic resonant scat- tering is quite different in three polymorphs, rutile, anatase and brookite [ ]. this reason is attributed to the different crystal structures and different site symmetries of ti. we can observe only the anisotropic part of the resonant scattering and the allowed multi-pole contributions to scattering are restricted by the site symmetry. therefore unfortunatelywe cannot select freely the scattering from specific electronic states. wenext considermagnetic effect on the resonant anisotropic scattering, and local chirality of atom in a centrosymmetric crystal. hematite,α-fe o [ , ], has corun- dum structure of rhombohedral crystal, the fe site symmetry is . for the forbidden reflections in hematite, d-d scattering is not allowed but d-q and q-q scatterings are allowed. in addition to the electric scattering the magnetic scattering can also affect the forbidden reflections because hematite has anti-ferromagnetic structure. in fact the non-resonant magnetic scattering was observed in hematite, though its intensity was much smaller than that of the resonant scattering. the observed forbidden and reflections in the crystal revealed one resonant peak only in the pre-edge energy region of the fe atom. figure shows the observed azimuth dependence of the and forbidden reflections intensity at the resonant energy. the azimuth dependence of the reflection shows almost threefold symmetry. this result is well explained by the interference between d-q and q-q scatterings. the crystal is cen- trosymmetric but the iron site have no inversion symmetry and the d-q contribution to the forbidden reflections depends on antisymmetric part of the third-rank tensor of the iron atomic susceptibility (remind that just the antisymmetric part is responsible for the effects of natural chirality in non-centrosymmetric crystals). therefore the observation of d-q scattering in the reflection is evidence of local chirality of the fe atom. on the other hand, the resonant reflection in hematite shows complicated azimuth dependence, nearly mirror symmetry. this result is well explained by inter- ference of non-resonant magnetic scattering with the d-q and q-q resonant electric scatterings. resonant magnetic scattering can also bring similar contribution to the reflection, but the effect is inconsistent with other experimental results. namely clear evidence of the resonantmagnetic scatteringwasnot found.fromthese results it the european physical journal special topics in te ns it y (a rb . u ni ts ) - - - azimuthal angle (degree) (a) fe o e = . kev obs. calc. . . . . . . in te ns it y (a rb . u ni ts ) - - - azimuthal angle (degree) (b) fe o e = . kev obs. calc. fig. . azimuthal angle dependence in hematite [ ]: (a) the and (b) the reflections at the resonant energy near the fe k pre-edge. the solid curves are calculated from a com- bination of the d-q, q-q resonant electric scatterings and non-resonant magnetic scattering. in the reflection the electric scatterings are dominant. is shown that the non-resonant magnetic scattering has a significant influence on the resonant electric scattering though its intensity ismuch smaller.thus the interference between themagnetic and electric scatterings plays a very important role in hematite forbidden reflections. this phenomenon opens new ways for studying additional details of the magnetic structure, for instance, it allows us to determine the sign of the dzyaloshinskii-moriya interactions in this class of antiferromagnetics with weak ferromagnetism [ , ]. very recently the sign has been really measured for another weak antiferromagnetic, febo [ ], using interference between resonant q-q scatter- ing and non-resonant magnetic scattering. moreover, in non-centrosymmetric mnsi crystal, it is possible to measure this way different components of the dzyaloshinskii- moriya vector never measured before [ ]. the polarization properties of resonant forbidden reflections provide a direct way to distinguish right and left enantiomorphs of crystals [ , ]. the structure factors and corresponding intensities of the screw-axis forbidden reflections in right-handed and left-handed crystals are very different for right and left circular polarizations even in pure d-d approximation. only recently this was experimentally confirmed for low quartz [ ] (sio , si k-edge), berlinite [ ] (alpo , p k-edge), cscucl [ ] resonant elastic x-ray scattering in condensed matter fig. . temperature dependence of thege forbidden reflection intensity at the resonant energy near the ge k-absorption edge [ , ]. the curve is calculated from the einstein model for optical phonons with the thermal motion correlation considered. (cu k-edge), and tellurium [ ] (te l -edge) crystals (see also the paper of tanaka [ ] in this issue). we finally consider the thermal-motion-induced contribution to forbidden reflec- tions. germanium crystal [ , , ] has the diamond structure and the atomic site symmetry is ̄ m. for this symmetry the d-d scattering factor is isotropic, there- fore the forbidden reflections cannot be allowed in dipole approximation. therefore the observed forbidden reflections should originate in other reasons. figure shows the temperature dependence of the forbidden reflection intensity at the resonant energy near the ge k edge. as shown in this figure the intensity strongly increases with temperature. from this result and the azimuth dependence we conclude that about / intensities at room temperature are pure d-q scattering but the other / intensities are caused by thermal-motion-induced (tmi) resonant scattering. by only the azimuth dependencewe cannot knowweather the scattering is caused bypure d-q or tmi scattering because the both azimuth dependences are completely the same. it is remarkable in the tmi scattering that the great enhancement of the intensity is observed in high temperature region. furthermore information of the thermalmotion correlation was derived from the tmi scattering in germanium [ ]. the tmi scat- tering at a forbidden reflection has been also observed in other crystals, zno [ ] and gan [ ]. theoretical simulations show that the tmi scattering is mainly caused by the optical phonon mode [ ]. therefore the tmi scattering can give a new method for studying the phonon property in crystal. we cannot review in this short paper other interesting and sometimes contro- versial phenomena studied via beautiful shine of forbidden reflections: a possible orbital ordering vs. the jahn-teller distortions in lamno [ , , , ], charge or- dering vs. atomic displacements during the verwey transition in magnetite [ – ], recent observation of orbital currents incuocrystals [ ] and extremely small atomic the european physical journal special topics displacements in multiferroics [ ] (see also numerous references therein). the for- bidden reflections are also used very successfully in soft x-ray region near l- or m-edges [ ]. conclusion abovewehave presented only a small part ofworks dealingwith forbidden reflections in resonant regions near x-ray absorption edges. using forbidden reflections we have exclusively detected the information about local anisotropy of x-ray susceptibility of resonant atoms. this experimental technique is a very sensitive and usefulmethod to study the local electronic states. inpyrite crystal,wehaveobtained separately the real and imaginary energy spectra of the anisotropic scattering factor byphase determina- tion method and compared this result with different type of theoretical simulations. we have studied not only the dipole resonant scattering but also the quadrupole effects in many crystals because the quadrupole effects can be clearly seen this way compared with other experimental methods. the dipole-quadrupole and quadrupole- quadrupole scattering amplitudes are more sensitive to the specific details of local electronic states (for instance, to hybridization of orbitals with different parity). we can observe even the local chirality at the atomic scale. the method of forbidden reflection is also useful for studying themagnetic properties of crystals including tiny effects related with the dzyaloshinskii-moriya interaction. furthermore, tmi reso- nant scattering can give a new opportunity to study the phonon displacements and the thermal motion correlations of atoms. we are grateful to m. blume and k. ishida for their permanent passion for forbidden reflec- tions encouraging us in our common work. references . d.h. templeton, l.k. templeton, acta crystallogr. sect. a , ( ) . a. petcov, a. kirfel, k. fischer, acta crystallogr. sect. a , ( ) . d.h. templeton, l.k. templeton, acta crystallogr. sect. a , ( ) . 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/colorimagemindownsampledepth /colorimagedownsamplethreshold . /encodecolorimages true /colorimagefilter /dctencode /autofiltercolorimages true /colorimageautofilterstrategy /jpeg /coloracsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /colorimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg coloracsimagedict << /tilewidth /tileheight /quality >> /jpeg colorimagedict << /tilewidth /tileheight /quality >> /antialiasgrayimages false /cropgrayimages true /grayimageminresolution /grayimageminresolutionpolicy /warning /downsamplegrayimages true /grayimagedownsampletype /bicubic /grayimageresolution /grayimagedepth - /grayimagemindownsampledepth /grayimagedownsamplethreshold . /encodegrayimages true /grayimagefilter /dctencode /autofiltergrayimages true /grayimageautofilterstrategy /jpeg /grayacsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /grayimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg grayacsimagedict << /tilewidth /tileheight /quality >> /jpeg grayimagedict << /tilewidth /tileheight /quality >> /antialiasmonoimages false /cropmonoimages true /monoimageminresolution /monoimageminresolutionpolicy /warning /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /createjdffile false /description << /ara /bgr /chs /cht /cze /dan /esp /eti /fra /gre /heb /hrv (za stvaranje adobe pdf dokumenata najpogodnijih za visokokvalitetni ispis prije tiskanja koristite ove postavke. stvoreni pdf dokumenti mogu se otvoriti acrobat i adobe reader . i kasnijim verzijama.) /hun /ita /jpn /kor /lth /lvi /nld (gebruik deze instellingen om adobe pdf-documenten te maken die zijn geoptimaliseerd voor prepress-afdrukken van hoge kwaliteit. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /pol /ptb /rum /rus /sky /slv /suo /sve /tur /ukr /enu (use these settings to create adobe pdf documents best suited for high-quality prepress printing. created pdf documents can be opened with acrobat and adobe reader . and later.) /deu >> /namespace [ (adobe) (common) ( . ) ] /othernamespaces [ << /asreaderspreads false /cropimagestoframes true /errorcontrol /warnandcontinue /flattenerignorespreadoverrides false /includeguidesgrids false /includenonprinting false /includeslug false /namespace [ (adobe) (indesign) ( . ) ] /omitplacedbitmaps false /omitplacedeps false /omitplacedpdf false /simulateoverprint /legacy >> << /addbleedmarks false /addcolorbars false /addcropmarks false /addpageinfo false /addregmarks false /convertcolors /converttocmyk /destinationprofilename () /destinationprofileselector /documentcmyk /downsample bitimages true /flattenerpreset << /presetselector /mediumresolution >> /formelements false /generatestructure false /includebookmarks false /includehyperlinks false /includeinteractive false /includelayers false /includeprofiles false /multimediahandling /useobjectsettings /namespace [ (adobe) (creativesuite) ( . ) ] /pdfxoutputintentprofileselector /documentcmyk /preserveediting true /untaggedcmykhandling /leaveuntagged /untaggedrgbhandling /usedocumentprofile /usedocumentbleed false >> ] >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice software development using c++: beauty-and-the-beast issues in informing science and information technology volume , cite as: mcmaster, k., sambasivam, s., & wolthuis, s. ( ). software development using c++: beauty and the beast. issues in informing science and information technology, , - . retrieved from http://iisit.org/vol /iisitv p - mcmaster .pdf software development using c++: beauty-and-the-beast kirby mcmaster lake forest college, lake forest, il, usa kmcmaster@weber.edu samuel sambasivam azusa pacific university, azusa, ca, usa ssambasivam@apu.edu stuart wolthuis byu – hawaii, laie, hi, usa stuart.wolthuis@byuh.edu abstract good programming style plays an important role in producing better software. good style makes source code easy to read and to understand. this will usually reduce programming errors and simplify maintenance. we discuss popular style practices in c++ software development. then we present a software program we have developed called uglycode. uglycode can be used by in- structors to demonstrate the effect of various programming style options on code readability. this software converts "beautiful" c++ source code into "beastly" versions that exaggerate bad pro- gramming style. specific examples to illustrate the use of uglycode are shown. with uglycode, programming style effects can be viewed interactively by showing the results when style features are changed in existing code. keywords: programming style, layout, ugly code, algorithm, c++. introduction teaching computer science students how to become competent programmers must go beyond explaining the syntax of a programming language. in programming courses, the early focus is on teaching a computer how to solve a problem (shustek, ). this includes a description of the main features of a higher-level language (e.g., c++, java, or python), along with ways to organize language statements into modules and working programs. as students gain programming knowledge, they are introduced to design and implementation of algorithms (dijkstra, ). characteristics of algorithms that receive sustained emphasis are cor- rectness, performance, and efficiency. eventually, to become professional pro- grammers, students must learn to de- velop systems that satisfy additional objectives, such as maintainability, us- ability, reliability, and security. these properties have become increasingly important as systems have become lar- ger, more complex, and interconnected. material published as part of this publication, either on-line or in print, is copyrighted by the informing science institute. permission to make digital or paper copy of part or all of these works for personal or classroom use is granted without fee provided that the copies are not made or distributed for profit or commercial advantage and that copies ) bear this notice in full and ) give the full citation on the first page. it is per- missible to abstract these works so long as credit is given. to copy in all other cases or to republish or to post on a server or to redistribute to lists requires specific permission and payment of a fee. contact publisher@informingscience.org to request redistribution permission. mailto:kmcmaster@weber.edu mailto:ssambasivam@apu.edu mailto:stuart.wolthuis@byuh.edu mailto:publisher@informingscience.org software development using c++ programming objectives with regard to correctness, programmers always desire to write software that is error-free. com- puting professionals with strong mathematics backgrounds tend to focus on logical correctness, as determined by proofs. a software development group in australia (klein et al., ) recently announced that they have finally proven their micro-kernel operating system to be correct. textbooks on algorithms provide proofs for many common algorithms (cormen, leiserson, rivest, & stein, ; sedgewick & wayne, ). however, proving an algorithm to be correct does not guarantee that the source code will be without errors. proofs also do not ensure that the program meets customer requirements. another way to verify program correctness is to perform thorough testing of the software while it is being developed. a well-designed test plan consists of a broad range of tests, both for individ- ual parts of the system and for the system as a whole. programmers also want to write programs that perform rapidly and make efficient use of com- puter resources. there are almost always trade-offs between performance and efficiency. in a sys- tem where multiple processes run concurrently, the primary responsibility for managing these tradeoffs is delegated to the operating system (silberschatz, galvin, & gagne, ). beyond the operating system, programmers can improve performance and efficiency through their choice of algorithms and data structures. programmers are introduced to the benefits of modular code in early programming courses (li- ang, : stroustrup, ) and data structures courses (dale, ; drozdek, ). the initial modules are functions and procedures. in object-oriented programming, the design and use of classes, objects, and encapsulation is a necessary way to manage complexity in larger programs. programming courses spend little time directly on maintainability. most software is not main- tained by the original developer. readability is essential for continual code maintenance. the de- partment of defense estimates that - % of software life cycle costs are for maintenance. modular code improves maintenance efforts, but other programming practices, such as agile de- velopment and configuration management, can also make code easier to correct and modify. de- tailed discussions appear in software engineering textbooks (pressman, ; somerville, ). programming style in the practice of programming, kernighan and pike ( ) ask why we should "bother" with programming style. "why worry about style? who cares what a program looks like if it works? doesn't it take too much time to make it look pretty? aren't the rules arbitrary anyway?" programming style involves ways that a programmer can organize and present code to make it more understandable to other programmers. by making code easier to understand, style im- provements can contribute to other desirable program characteristics. for example, readable code is more likely to be correct when initially written. it is easier to modify when changes are re- quired. programming style can also assist software testing to verify program correctness. customers want programs that are correct, perform well, make efficient use of resources, and meet requirements. good programming style helps programmers provide these properties in the software they develop. we teach programming style because it helps students acquire the ability to write professional quality code. the remainder of this paper covers programming style concepts, our uglycode software, and c++ code examples. in the next section, we describe style concepts that involve source code lay- out and content. in the third section, we introduce our uglycode software, which can be used by mcmaster, sambasivam, & wolthuis instructors to display the effect of different style choices on code readability. the fourth section presents c++ style examples that demonstrate the use of uglycode. c++ programming style the purpose of programming style is to help programmers interpret what the code of other pro- grammers (and their own code) is actually doing. but which programming style is best? expert programmers have their own preferred styles for writing code. one common point of consensus is that style choices should be used consistently. in the elements of programming style, kernighan and plauger ( ) describe a number of style choices for programmers. we discuss a partial list of their style topics, organized into layout and content groups. program layout program layout consists of techniques to rearrange source code to make it more readable. no con- tent is added to the code--just changes in spacing. blank lines: blank lines can be added to source code between functions and to group lines of code together that perform some computing activity. this makes the organization of the code easier to discern. indenting: another way to visually present lines of code that "belong together" is to use the same level of indentation for the lines. because source code can have nested blocks, more than one level of indentation can be helpful. indenting is also used to indicate that a statement wraps over more than one line. one question that always generates a variety of responses is "how many spaces should i indent?" each programmer will have a preferred answer, and many software development environments provide explicit standards. block layout: a block of code is a sequence of statements having the behavior that either all statements are executed, or none are. in a conditional statement, the block is executed only when the condition is true. in iterative statements, the block will be executed repeatedly until the con- tinuation status changes. an important part of block layout is placing marks in the code where each block starts and ends. formatting conventions for blocks depend on the programming language. in a language with fully-bracketed syntax (e.g., if-endif), the statements include markers for the start and end of blocks. some recent languages such as c, c++, and java use curly braces (e.g., "{ ... }") to mark blocks (kernighan & ritchie, ). for these languages, there are differences of opinion on where to place the curly braces. statement length: early fixed-format higher level languages such as fortran and cobol were designed with punched cards in mind, having a maximum of characters per card. in these languages, a statement will continue across more than one card only if marked in a special way. most recent languages are free-format, in that a statement is assumed to continue across multiple lines until a termination character (e.g., ";") appears. the programmer has the choice of how wide each line of code should be. multiple lines, with carefully selected break points, can be used for longer statements. software development using c++ providing content a programmer can also improve the readability of code by adding information within the state- ments. common ways to provide this information are through the choice of names for variables and the inclusion of comments at appropriate locations in the code. variable names: the value of a variable changes during the execution of a program. to allow references to the current value, a variable must be given a name. ideally, the name will describe the attribute represented by the variable. very short names and heavily abbreviated names can be cryptic to readers. comments: comments can be placed in source code for most programming languages. some spe- cial marking is usually required (e.g., "//") to indicate that the comment will not be executed. mcconnell ( ) recommends that comments be included only if they ( ) describe the code's intent, ( ) provide information not in the code, or ( ) summarize a section of code. c++ allows several types of comments: full-line comments, end-line comments, and multiple-line comments. uglycode software we have written a program called uglycode to assist instructors in teaching programming style. the uglycode software teaches programming style concepts in reverse. the usual forward teach- ing approach displayed in textbooks shows examples of "ugly" (beast) code, before applying de- sirable style principles to generate "pretty" (beauty) code. for uglycode, the input is a c++ program that has been written to illustrate good programming style. using uglycode, options can be exercised on how to "degrade" the code. students can see how much harder it is to understand source code when good style features are removed. instruc- tors can demonstrate programming style concepts using both "forward" (textbook) and "reverse" (uglycode) examples. our explanation of how to use the uglycode software is organized according to the user-interface controls that appear on the main screen. the controls include a file menu, six sets of checkboxes to select code style changes, and two command buttons to transform and restore the original code. file menu this is the only menu choice on the uglycode screen. it includes the following submenu options. . open: open an existing source code file, using a "file-chooser" input control. uglycode is de- signed for c++ (and java) programs. . save as: after style selections are made and viewed, the resulting "ugly" version of the original program can be saved as a text file. to avoid overwriting the input file, the name for the saved file should differ from the input file name. . exit: this option ends the uglycode program. command buttons two buttons on the lower right-hand corner of the screen are used to invoke actions on the source code. ugly it!: after one or more style options have been selected using the checkboxes, this button should be clicked to activate the changes on the original source code. the restyled "ugly" code then appears in the main window. reset text: clicking this button will restore the code in the window to its original form. mcmaster, sambasivam, & wolthuis checkboxes checkboxes are organized into groups, based on style category. within each group, the check- boxes act like command buttons, in that at most one box can be checked. the following checkbox groups are listed on the right-hand side of the uglycode main screen. line spacing line spacing choices display how the inclusion or exclusion of blank lines in code can affect pro- gram readability. blank lines can make it easier to see which parts of the code belong together. we include three spacing options. remove blank lines: selecting this checkbox causes all blank lines to be removed from the code. this choice is equivalent to single-spacing. double space code: double-spacing rarely appears in production code, although a few develop- ers embrace it. this style choice is included to contrast with single-spacing. in a work environ- ment, the extra blank lines in code could be used for inserting notes during code reviews. stu- dents often use double-spacing when writing term papers for non-computer courses. we have seen the equivalent of double-spacing in code from students, when they copy their code into mi- crosoft word. the current default spacing in word places points at the end of each line, which students (and lab administrators) often fail to change. random blank lines: blank lines do not improve program readability when the lines are inserted in apparently random locations. this option inserts blank lines randomly into the code. after each non-blank line, the probability is / that the next line will be blank. combined with random in- denting (described below), this option can lead to "beastly" looking code. indenting we provide three options for the number of spaces that occur on the left side of each line of code. remove indents: with this option, all spaces on the left of each line are trimmed off. all code starts at the left-side margin. this makes it hard to identify where branching and looping control structures start and end. add fixed-size indents: the "best" size for indenting is an individual preference among pro- grammers. with this option, the instructor can demonstrate the readability of code with various indenting sizes. choosing zero spaces is equivalent to removing all indents. a pop-up window allows the user to enter the desired number of spaces per indent. within nested control structures, multiple levels of indenting can accumulate on a single line. add random indents: in this selection, each line receives a random indent size of to spaces. this is certainly not a recommended way to indent, but a similar result sometimes occurs in stu- dent assignments. suppose that code is written using an editor with a fixed-size indent (say ), but the programmer mixes spaces with tabs. when the code is later brought into a different editor (e.g., notepad with tab size ), the mixture of new tab sizes and old spaces can yield a ragged left margin for the code. randomly-indented code can be a "beast" to debug. curly braces a common layout decision is "where to put curly braces to designate the start and end of blocks." the decision can be guided by language traditions, as well as by programmer preferences. c, c++, and java have separate histories, with different preferred block marking rules. this option allows the instructor to compare the traditional c-style braces with java-style braces, allowing students to form their own opinions. software development using c++ change to java style: with this choice, curly braces defining blocks for loops (while, for) and branches (if-else) are formatted to have the opening brace on the same line as the decision expres- sion. curly braces in other parts of the code are not changed. change to c style: with this choice, curly braces are formatted with each opening brace on its own separate line. closing braces in the code are not changed. comments comments can improve understanding of what the original programmer intended to do, but only if the comments are well-placed and are "helpful". uglycode options include ( ) removing com- ments and ( ) replacing existing comments with "useless" comments. uglycode acts only on sin- gle-line comments that start with "//". other comment delimiters (e.g., /* and */) are ignored. remove comments: with this option, all comments starting with "//" are removed from the source code. for full-line comments, the entire line is removed. for an end-line comment, the comment is removed, but not the source code before the comment. change to useless comments: this option replaces all full-line and end-line comments with "use- less" comments. for full-line comments, uglycode chooses randomly from a list of computer- humor statements we found on the web. for example, one of our favorite full-line comments is, "when your hammer is c++, every problem looks like a thumb." end-line comments are usually shorter, so the program chooses randomly from a list of popu- lar desserts (to sidetrack hungry programmers). for example, one end-line dessert is: "chocolate mousse". for both single-line and end-line comments, the replacement comments are not relevant to the code. repeating this option will give a different random sample of useless comments. variable names many variable naming styles are language specific (e.g., the preference for lower case names in c). most naming conventions recommend the use of "meaningful names", subject to possible name length restrictions. for example, "computedtax" is self-descriptive, while “ct” could be construed as an eastern us state or a medical diagnostic procedure. the variable naming options in uglycode show how atypical naming rules can hinder program understanding. change case: this option demonstrates how case differences can affect readability. for variables with common type declarations (e.g., char, int, long, float, double) that appear at the start of a line, the case of various characters in the variable name are changed (from lower-case to upper- case, or vice-versa). for example, a lower-case name such as "job_cost" might be changed to "job_cost". a name such as "netincome" could become "netincome". use meaningless names: whether a variable name is considered "meaningless" depends on the context. there are many ways to create meaningless names. we chose a simple encryption algo- rithm, a caesar cipher, because it is easy to program and generates strange looking names. each case-sensitive letter in a name is changed to the letter k positions later in the alphabet (with wrap- around). the value of shift k varies each time this option is invoked. non-letters are unchanged. for example, the variable "best buy" using shift k = would become "ehvw exb", which looks quite meaningless. mcmaster, sambasivam, & wolthuis line breaks in free-format languages such as c++, the programmer can choose how much of each statement to place on a line. for long statements, line breaks within a statement can improve the readability of the code. for short statements, more than one statement can be included on a single line. set line length: this option shows what the code will look like if a line length is specified. a pop-up window allows the user to enter a desired minimum line length (e.g., ). the code is then reformatted so that when concatenated statements exceed this length, they are split over addi- tional lines. a line break is placed in the first "safe" position at or beyond the minimum length. "safe" is defined to be immediately after the first semicolon (";"), left brace ("{"), right brace ("}"), or plus-sign with space ("+ ") at or beyond the minimum length. these break points are usually safe, but in some situations they can lead to compile errors. remove line breaks: this is the ultimate reformatting of source code. all line breaks are re- moved and replaced with spaces. the program now consists of a single long line, which is what a compiler sees. because the uglycode window shows this line without word-wrap, the window's bottom slider control must be used to view the entire program. the revised one-line program can be saved and then viewed in an editor that provides word-wrap (e.g., notepad). note: after making programming style changes, the resulting c++ program can be saved as a text file. if you are fortunate, the revised program will compile and run. for example, if remove blank lines, remove indents, remove comments, change case (for variable names), and re- move line breaks are all checked, the reformatted program should execute exactly as before the changes. the source code is much more "beastly", but the compiler/computer doesn't care. code style changes are not cumulative. each set of selected changes is applied to the original source code. if an instructor wants to demonstrate the cumulative effects of style changes, she/he should plan a sequence of changes and then mark cumulative sets of checkboxes for ugly it! but- ton clicks. c++ style examples several examples of how style concepts can reduce the clarity of a c++ program are described in this section. each example uses the sample code for the gcd (greatest common divisor) function listed below. long gcd(long n , long n ) { // euclidean algorithm for gcd long high, low, remainder; // initialize high and low if(n > n ) { high = n ; low = n ; } else { software development using c++ high = n ; low = n ; } // loop until remainder is remainder = high % low; while(remainder > ) { high = low; low = remainder; remainder = high % low; } return low; } // end gcd figure : original c++ code for gcd function. the gcd function calculates the greatest common divisor of two integers n and n . we display uglycode output to show the beast effect of selected programming style choices on this code. remove blank lines and comments the first c++ example demonstrates the combined effect of removing all blank lines and com- ments. the code with the comments and blank lines removed is shown in figure . long gcd(long n , long n ) { long high, low, remainder; if(n > n ) { high = n ; low = n ; } else { high = n ; low = n ; } remainder = high % low; while(remainder > ) { high = low; low = remainder; mcmaster, sambasivam, & wolthuis remainder = high % low; } return low; } // end gcd figure : ugly c++ code with blank lines and comments removed. the function name (gcd acronym) suggests the purpose of the function. the shorter transformed code for the function is still readable, but more effort is required to understand the structure of the algorithm. java curly braces with no indenting the next c++ example shows how readability suffers when all indenting is removed. the code without indenting but with java-style braces is presented in figure . long gcd(long n , long n ) { // euclidean algorithm for gcd long high, low, remainder; // initialize high and low if(n > n ) { high = n ; low = n ; } else { high = n ; low = n ; } // loop until remainder is remainder = high % low; while(remainder > ) { high = low; low = remainder; remainder = high % low; } return low; } // end gcd figure : ugly c++ code with java-style braces and no indenting. software development using c++ the code is reasonably clear, thanks to the comments. the change to java style braces has little effect on readability, but it does reduce the number of lines. however, the lack of indentation makes it harder to distinguish the boundaries of the blocks for the if statement and while loop. meaningless names & useless comments the third c++ example demonstrates how poorly chosen variable names and unhelpful comments can affect program readability. the transformed code is shown in figure . long jfg(long q , long q ) { // beware of bugs in this code; i have only proved it correct. long kljk, orz, uhpdlqghu; // you can't make a good program without breaking some egos. if(q > q ) { kljk = q ; orz = q ; } else { kljk = q ; orz = q ; } // when your hammer is c++, every problem looks like a thumb. uhpdlqghu = kljk % orz; while(uhpdlqghu > ) { kljk = orz; orz = uhpdlqghu; uhpdlqghu = kljk % orz; } return orz; } // hot fudge sundae figure : ugly c++ code with meaningless names and useless comments. the uglycode program scrambles the names of variables (and functions) that are type-declared at the start of a statement. we do not scramble the names of variables declared within statements, such as argument names and counter variables declared inside loops. the scrambled name "uhpdlqghu" is virtually meaningless. mcmaster, sambasivam, & wolthuis for comments to be effective, they must provide information that is helpful to programmers who later read the source code. instead of removing the comments, we replace them with comments that have nothing to do with the code (e.g., "a million monkeys..."). the above programming style examples illustrate the utility of the uglycode software for interac- tive classroom use. with six style groups and - choices per group, there are a total of possi- ble cases involving a single style change. when several style changes are combined, or when the cumulative effects of a sequence of changes are examined, the number of cases increases dra- matically. not all cases will be of equal interest. a variety of sample programs can be prepared to demonstrate specific style combinations to students. summary and conclusions in this paper, we discussed how programming style can affect source code understanding. we related programming style to program features such as correctness, performance, efficiency, and maintainability. we presented several style options for c++ program layout, such as blank lines, indenting, and block layout. we also described style features such as variable names and com- ments that add content to improve readability. we described a program we have written called uglycode, which allows an instructor to demon- strate how style changes affect the clarity of code. instead of showing an example of "bad" (beast) code and then making it "pretty" (beauty), uglycode works in the opposite direction. pro- gram input should be a c++ program written in "good" style. style changes are then requested, and the resulting degradation of the code can be viewed immediately. the uglycode software allows students to see the effect of individual style changes and groups of changes. transformed source code can be saved in a text file. students can attempt to compile and run the modified code. in this way, they can determine whether or not the style changes dis- rupt the compiler. it is surprising to see how often style changes are ignored by c++ compilers. future research we have demonstrated prototypes of the uglycode software in programming and software engi- neering courses. the data we have collected from students is largely anecdotal. with a completed version of uglycode now available, we plan to measure how well this tool helps students appre- ciate the importance of good programming style. note: an executable version of the uglycode program, along with the sample c++ program pre- sented in this paper, can be obtained from the authors. references cormen, t., leiserson, c., rivest, r., & stein, c. ( ). introduction to algorithms ( rd ed). mit press. dale, n. ( ). c++ plus data structures ( th ed). jones & bartlett. dijkstra, e. w. ( ). a short introduction to the art of programming. e. w. dijkstra archive. retrieved from http://www.cs.utexas.edu/users/ewd/ drozdek, a. ( ). data structures and algorithms in c++ ( th ed). cengage learning. kernighan, b. w., & pike, r. ( ). the practice of programming. addison-wesley. kernighan, b. w., & plauger, p. j. ( ). the elements of programming style ( nd ed). mcgraw-hill. kernighan, b. w., & ritchie, d. m. ( ). the c programming language ( nd ed). prentice hall. http://www.cs.utexas.edu/users/ewd/ software development using c++ klein, g., elphinstone, k., heiser, g., andronick, j., cock, d., derrin, p., ... & winwood, s. ( , octo- ber). formal verification of an os kernel. proceedings of the acm sigops nd symposium on op- erating systems principles (pp. - ). acm. liang, y. d. ( ). introduction to programming with c++ ( rd ed). prentice hall. mcconnell, s. ( ). code complete ( nd ed). microsoft press. pressman, r. ( ). software engineering: a practitioner's approach ( th ed). mcgraw-hill. sedgewick, r., & wayne, k. ( ). algorithms ( th ed). addison-wesley. shustek, l. ( ). donald knuth: a life's work interrupted. communications of the acm, ( ), - . silberschatz, a., galvin, p. b., & gagne, g. ( ). operating system concepts ( th ed). wiley. somerville, i. ( ). software engineering ( th ed). addison-wesley. stroustrup, b. ( ). the c++ programming language ( th ed). addison-wesley. biographies dr. kirby mcmaster recently retired from the computer science de- partment at weber state university. to remain active, he is currently a visiting professor in computer science at lake forest college in illi- nois. his primary research interests are in database systems, software engineering, and frameworks for computer science and mathematics. dr. samuel sambasivam is chairman and professor of the computer science department at azusa pacific university. his research interests include optimization methods, expert systems, client/server applica- tions, database systems, and genetic algorithms. he served as a distinguished visiting professor of computer science at the united states air force academy in colorado springs, colorado for a year. he has conducted extensive research, written for publications, and de- livered presentations in computer science, data structures, and mathematics. he is a voting member of the acm and is a member of the institute of electrical and electronics engineers (ieee). stuart l. wolthuis is assistant professor in the computer & informa- tion sciences department at brigham young university--hawaii. his teaching focus includes software engineering, hci, and information assurance. he brings almost years of service in the usaf to the classroom with real world experiences as a program manager and software engineer. when not enjoying hawaii’s great outdoors, his research interests include melding together information systems and marine biology. his current project, ocean view, will link land-locked educators and students to live underwater ocean views via an educa- tional website. software development using c++:beauty-and-the-beast kirby mcmasterlake forest college, lake forest, il, usa kmcmaster@weber.edu samuel sambasivamazusa pacific university, azusa, ca, usa ssambasivam@apu.edu stuart wolthuisbyu – hawaii, laie, hi, usa stuart.wolthuis@byuh.edu abstract introduction programming objectives programming style c++ programming style program layout providing content uglycode software file menu command buttons checkboxes line spacing indenting curly braces comments variable names line breaks c++ style examples remove blank lines and comments java curly braces with no indenting meaningless names & useless comments summary and conclusions future research references biographies defining and identifying sleeping beauties in science qing ke, emilio ferrara, filippo radicchi, and alessandro flammini center for complex networks and systems research, school of informatics and computing, indiana university, bloomington, in edited by mark e. j. newman, university of michigan, ann arbor, mi, and accepted by the editorial board april , (received for review december , ) a sleeping beauty (sb) in science refers to a paper whose impor- tance is not recognized for several years after publication. its ci- tation history exhibits a long hibernation period followed by a sudden spike of popularity. previous studies suggest a relative scarcity of sbs. the reliability of this conclusion is, however, heavily dependent on identification methods based on arbitrary threshold parameters for sleeping time and number of citations, applied to small or monodisciplinary bibliographic datasets. here we present a systematic, large-scale, and multidisciplinary analysis of the sb phe- nomenon in science. we introduce a parameter-free measure that quantifies the extent to which a specific paper can be considered an sb. we apply our method to million scientific papers published in all disciplines of natural and social sciences over a time span longer than a century. our results reveal that the sb phenomenon is not exceptional. there is a continuous spectrum of delayed rec- ognition where both the hibernation period and the awakening intensity are taken into account. although many cases of sbs can be identified by looking at monodisciplinary bibliographic data, the sb phenomenon becomes much more apparent with the analysis of multidisciplinary datasets, where we can observe many examples of papers achieving delayed yet exceptional importance in disciplines different from those where they were originally published. our analysis emphasizes a complex feature of citation dynamics that so far has received little attention, and also provides empirical ev- idence against the use of short-term citation metrics in the quanti- fication of scientific impact. delayed recognition | sleeping beauty | bibliometrics there is an increasing interest in understanding the dynamicsunderlying scientific production and the evolution of science ( ). seminal studies focused on scientific collaboration networks ( ), evolution of disciplines ( ), team science ( – ), and citation- based scientific impact ( – ). an important issue at the core of many research efforts in science of science is characterizing how papers attract citations during their lifetime. citations can be regarded as the credit units that the scientific community at- tributes to its research products. as such, they are at the basis of several quantitative measures aimed at evaluating career tra- jectories of scholars ( ) and research performance of institutions ( , ). they are also increasingly used as evaluation criteria in very important contexts, such as hiring, promotion, and tenure, funding decisions, or department and university rankings ( , ). several factors can potentially affect the amount of citations ac- cumulated by a paper over time, including its quality, timeliness, and potential to trigger further inquiries ( ), the reputation of its authors ( , ), as well as its topic and age ( ). studies about fundamental mechanisms that drive citation dynamics started already in the s, when de solla price in- troduced the cumulative advantage (ca) model to explain the emergence of power-law citation distributions ( ). ca essen- tially provisions that the probability of a publication to attract a new citation is proportional to the number of citations it already has. the criterion, now widely referred to as preferential at- tachment, was recently popularized by barabási and albert ( ), who proposed it as a general mechanism that yields het- erogeneous connectivity patterns in networks describing sys- tems in various domains ( , ). other processes that effec- tively incorporate the ca mechanism have been proposed to explain power-law citation distributions. krapivsky and redner, for example, considered a redirection mechanism, where new papers copy with a certain probability the citations of other papers ( ). an important effect not included in the ca mechanism is the fact that the probability of receiving citations is time dependent. in the ca model, papers continue to acquire citations inde- pendently of their age so that, on average, older papers accu- mulate higher number of citations ( , , ). however, it has been empirically observed that the rate at which a paper accu- mulates citations decreases after an initial growth period ( – ). recent studies about growing network models include the aging of nodes as a key feature ( , – ). more recently, wang et al. developed a model that includes, in addition to the ca and aging, an intuitive yet fundamental ingredient: a fitness or quality parameter that accounts for the perceived novelty and impor- tance of individual papers ( ). in this work, we focus on the citation history of papers receiving an intense but late recognition. note that delayed recognition cannot be predicted by current models for citation dynamics. all models, regardless of the number of ingredients used, naturally lead to the so-called first-mover advantage, according to which either papers start to accumulate citations in the early stages of their lifetime or they will never be able to accumulate a significant number of citations ( ). back in the s, garfield provided examples of articles with delayed recognition and suggested to use citation data to identify them ( – ). through a broad literature search, glänzel et al. gave an estimate for the occur- rence of delayed recognition, and highlighted a few shared fea- tures among lately recognized papers ( ). the coinage of the term “sleeping beauty” (sb) in reference to papers with delayed recognition is due to van raan ( ). he proposed three dimensions along which delayed recognition can be measured: (i) length of sleep, i.e., the duration of the “sleeping period;” significance scientific papers typically have a finite lifetime: their rate to attract citations achieves its maximum a few years after publi- cation, and then steadily declines. previous studies pointed out the existence of a few blatant exceptions: papers whose rele- vance has not been recognized for decades, but then suddenly become highly influential and cited. the einstein, podolsky, and rosen “paradox” paper is an exemplar sleeping beauty. we study how common sleeping beauties are in science. we in- troduce a quantity that captures both the recognition intensity and the duration of the “sleeping” period, and show that sleeping beauties are far from exceptional. the distribution of such quantity is continuous and has power-law behavior, sug- gesting a common mechanism behind delayed but intense rec- ognition at all scales. author contributions: q.k., e.f., f.r., and a.f. designed research; q.k. performed re- search; q.k., e.f., f.r., and a.f. analyzed data; and q.k., e.f., f.r., and a.f. wrote the paper. the authors declare no conflict of interest. this article is a pnas direct submission. m.e.j.n. is a guest editor invited by the editorial board. to whom correspondence should be addressed. email: aflammin@indiana.edu. this article contains supporting information online at www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental. – | pnas | june , | vol. | no. www.pnas.org/cgi/doi/ . /pnas. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://crossmark.crossref.org/dialog/?doi= . /pnas. &domain=pdf mailto:aflammin@indiana.edu http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental www.pnas.org/cgi/doi/ . /pnas. (ii) depth of sleep, i.e., the average number of citations during the sleeping period; and (iii) awake intensity, i.e., the number of citations accumulated during y after the sleeping period. by combining these measures, he identified a few sb examples that occurred between and . these seminal studies suffer from two main limitations: (i) the analyzed datasets are very small, especially if compared with the size of the bibliographic databases currently available; and (ii) the definition and the consequent identification of sbs are to the same extent arbitrary, and strongly depend on the rules adopted. more recently, redner analyzed a very large dataset covering y of publications in physics ( ). redner proposed a definition of revived classic (or sb) for articles satisfying the three following criteria: (i) publication date ante- cedent ; (ii) number of citations larger than ; and (iii) ratio of the average citation age to publication age greater than . . whereas redner was able to overcome the first limitation mentioned above, his study is still affected by an arbitrary se- lection choice of top sbs, justified by the principle that sbs represent exceptional events in science. in addition, redner’s analysis has the limitation to be field specific, covering only publications and citations within the realm of physics. here we perform an analysis on the sb phenomenon in sci- ence. we propose a parameter-free approach to quantify how much a given paper can be considered as an sb. we call this index “beauty coefficient,” denoted as b. by measuring b for tens of millions of publications in multiple scientific disciplines over an observation window longer than a century, we show that b is characterized by a heterogeneous but continuous distribution, with no natural separation between papers with low, high, or even extreme values of b. also, we demonstrate that the em- pirical distributions of b cannot be easily reconciled with obvious baseline models for citation accumulation that are based solely on ca or the reshuffling of citations. we introduce a simple method to identify the awakening time of sbs, i.e., the year when their citations burst. the results indicate that many sbs become highly influential more than y after their publication, far longer than typical time windows for measuring citation impact, corroborating recent studies on understanding the use of short time windows to approximate long-term citations ( – ). we further show that the majority of papers exhibit a sudden decay of popularity after reaching the maximum number of yearly ci- tations, independently of their b values. our study points out that the sb phenomenon has two important multidisciplinary components. first, particular disciplines, such as physics, chem- istry, and mathematics, are able to produce top sbs at higher rates than other scientific fields. second, top sbs achieve delayed exceptional importance in disciplines different from those where they were originally published. based on these results, we believe that our study may pave the way to the identification of the com- plex dynamics that trigger the awakening mechanisms, shedding light on highly cited papers that follow nontraditional popu- larity trajectories. materials and methods beauty coefficient. the beauty coefficient value b for a given paper is based on the comparison between its citation history and a reference line that is determined only by its publication year, the maximum number of citations received in a year (within a multiyear observation period), and the year when such maximum is achieved. given a paper, let us define ct as the number of citations received in the tth year after its publication; t indicates the age of the paper. let us also assume that our index b is measured at time t = t, and that the paper receives its maximum number ctm of yearly citations at time tm ∈ ½ , t�. consider the straight line ℓt that connects the points ð , c Þ and ðtm, ctm Þ in the time–citation plane (fig. ). this line is described by the equation ℓt = ctm − c tm · t + c , [ ] where ðctm − c Þ=tm is the slope of the line, and c the number of citations received by the paper in the year of its publication. for each t ≤ tm, we then compute the ratio between ℓt − ct and maxf , ctg. summing up the ratios from t = to t = tm, the beauty coefficient b is defined as b = xtm t= ctm − c tm · t + c − ct maxf , ctg . [ ] by definition, b = for papers with tm = . papers with citations growing linearly with time ðct = ℓtÞ have b = . b is nonpositive for papers whose ci- tation trajectory ct is a concave function of time. our index b has a number of desirable properties: (i) b can be computed for any paper and does not rely on arbitrary thresholds on the sleeping period or the awakening in- tensity, paving the way to treat the sb phenomenon not as just an excep- tion; (ii) b increases with both the length of the sleeping period and the awakening intensity; (iii) b takes into account the entire citation history in the time window ≤ t ≤ tm; and (iv) the denominator of eq. penalizes early citations so that, at parity of total citations received, the later those citations are accumulated the higher is the value of b. awakening time. we now give a plausible definition of awakening time—the year when the abrupt change in the accumulation of citations of sbs occurs. being able to pinpoint the awakening time may help identify possible general trigger mechanisms behind said change. for example, in si appendix we show that around the awakening time, the sbs cocitation dynamics ex- hibit clear topical patterns (si appendix, fig. s ) ( ). we define the awakening time ta as the time t at which the distance dt between the point ðt, ctÞ and the reference line ℓt reaches its maximum: ta = arg � max t≤tm dt � , [ ] where dt is given by dt = jðctm − c Þt − tmct + tmc jffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ðctm − c Þ + t m q . as we shall show, the above definition works well for limit cases where there are no citations until the spike, and seems to well capture the qualitative notion of awakening time when a strong sb-like behavior is present. datasets. we use two datasets in the following empirical analysis, the american physical society (aps) and the web of science (wos) dataset (si appendix, section s ). the aps journals are the major publication outlets in physics. wos includes papers in both sciences and social sciences. we focus on the , papers in the aps and , , papers in the wos that received at least one citation. those papers span more than a century, and thus allow us to investigate the sb phenomenon for a long observation fig. . illustration of the definition of the beauty coefficient b (eq. ) and the awakening time ta (eq. ) of a paper. the blue curve represents the num- ber of citations ct received by the paper at age t (i.e., t represents the number of years since its publication). the black dotted line connecting the points ð , c Þ and ðtm, ctm Þ is the reference line ℓt (eq. ) against which the citation history of the paper is compared. the awakening time ta ≤ tm is defined as the age that maximizes the distance from ðt, ctÞ to the line ℓt (eq. ), in- dicated by the red dashed line. the red vertical line marks the awakening time ta calculated according to eq. . the figure refers to ref. . ke et al. pnas | june , | vol. | no. | a p p li ed p h y si c a l sc ie n c es so c ia l sc ie n c es d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf period. whereas the aps dataset can be viewed as a perfect proxy to characterize citation dynamics within the monodisciplinary research field of physics and is used to compare our analysis with a previous study ( ), the wos dataset allows us to underpin multidisciplinary features of the sb phenomenon. results sbs in physics. first, we qualitatively demonstrate the resolution power of b for four papers with radically different citation trajectories. fig. a shows a paper with a very high b value. published in , this paper collected a small number of yearly citations until , when it suddenly started to receive many citations until reaching its maximum in . fig. b exhibits a qualitatively similar citation trajectory for a recently published paper with a very low ctm and consequently a much smaller b. the paper in fig. c achieved its maximum yearly citations at t = . the citation history ct therefore coincides with the refer- ence line ℓt in ≤ t ≤ tm, yielding b = . note that our measure b only examines how the citation curve reaches its peak, but does not consider how it decreases after that. the paper in fig. d is characterized by a negative b value, as ct is above the reference line. second, we test the effectiveness of b to identify top sbs in the aps by using the revived classics, previously identified by redner, as a benchmark set ( ). our results are in excellent agreement with redner’s analysis ( ): out of the revived classics detected by redner are in our top list; the other have also very high b values, although they occupy less important positions in the ranking according to b (si appendix, table s ). differences are due to the principles underlying the two ap- proaches, with ours not relying on threshold parameters for the sleeping time and the number of citations. to better clarify the diversity of the two approaches, si appendix, figs. s and s report the citation history of the papers with highest b values in the aps dataset. we see that our measure identifies papers with a long hibernation period followed by a sudden burst in yearly citations, without the need to reach extremely high values of citations. as already pointed out by redner ( ), the list of top sbs in the aps reveals a natural grouping into a relatively small number of coarse topics, with papers belonging to the same topic exhibiting remarkably similar citation histories (si appen- dix, fig. s ). this suggests that a “premature” topic may fail to attract community attention even when it is introduced by au- thors who have already established a strong scientific reputation. a corroborating evidence is provided by the famous epr paradox paper by einstein, podolsky, and rosen that is among the top sbs we found in this dataset (si appendix, fig. s b). how rare are sbs? in contrast with previous sb definitions ( – ), ours does not rely on the arbitrary choice of age or citation thresholds. this fact puts us in the unique position of investi- gating the sb phenomenon at the systemic level and asking fundamental questions from the macroscopic point of view: are papers with extreme values of b exceptional occurrences? do the majority of papers behave in a qualitatively different way from the extreme cases discussed above, when their sleeping period and bursty awakening are considered? to this end, we provide a statistical description of the distri- bution of beauty coefficients across all papers in each of the two datasets. fig. shows the survival distribution functions of b for all papers in the aps and wos datasets. we observe a hetero- geneous but continuous distribution of b, spanning several or- ders of magnitude. except for the cutoff—which is much larger for the wos dataset—aps and wos exhibit remarkably similar distributions. although the vast majority of papers exhibit low values of b, there is a consistent number of papers with high b. the distributions also show no typical value or mode; there are no clear demarcation values that allow us to separate sbs from “normal” papers: delayed recognition occurs on a wide and con- tinuous range, in sharp contrast with previous results claiming that sbs are extraordinary cases ( , , ). it may appear as not entirely fair to compare beauty coefficients for papers of different ages ( ): later papers have by definition less chance to develop a long sleeping period and to exhibit a sudden awakening. this may, to some extent, dictate the shapes of observed distributions. on the other hand, the vast majority of papers tend to have a single and well-defined peak in their yearly citations early during their lifetime, implying that their b values do not change with moving the observation time t far into the future. in particular, our estimations indicate that nearly % of the papers have already experienced a drastic decrement after their maximum number of yearly citations, irrespective of their b value (si appendix, section s ). the shapes of the empirical dis- tributions remain essentially unchanged if we consider only the papers that have experienced the typical sharp decline of the post- maximum yearly citation rate. a b c d fig. . dependence of the beauty coefficient on citation history. blue curves show yearly citations of four papers with different b values in the aps dataset: (a) ref. , b = , ; (b) ref. , b = ; (c) ref. , b = ; (d) ref. , b = − . red lines indicate their awakening time. the awakening year in c is , i.e., ta = . fig. . survival distribution functions of beauty coefficients. on the horizontal axis, we shift the values by (i.e., the minimal value of b is − . ) to make all points visible in the logarithmic scale. the blue and cyan curves represent the empirical results obtained on the aps and wos datasets, respectively. results obtained with the nr and pa model are plotted as green and magenta lines, respectively. the red dashed line stands for the best estimate of a power-law fit of the aps curve: expo- nent α = . and the minimum value of the range of the fit bm = . are estimated using the statistical methods developed by clauset et al. ( ). in the aps and wos, . % and . % of papers, respectively, have negative b values. | www.pnas.org/cgi/doi/ . /pnas. ke et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf www.pnas.org/cgi/doi/ . /pnas. is the sb phenomenon statistically significant? the result of the previous section implicitly suggests that the sb phenomenon could be in principle described via a simple mechanism that works essentially at all scales. this leads naturally to the question whether the observed distributions of b can be accounted for by idealized network evolution models. to address this question, we first consider a citation network randomization (nr) process where citations are randomly reshuffled, preserving time order (si appendix, section s ). si appendix, fig. s compares the citation history of the top nine sbs in the aps dataset and the corresponding ones obtained through the nr process. they typically show opposite trends, with nr histories exhibiting a rapid decline. this is not surprising: as later papers are consid- ered, the probability for an existing paper to receive a citation from one of such late papers decreases simply because there is a larger number of papers that could potentially receive the citation. this leads to typically smaller beauty coefficients, as evident in the sharp decrease of the nr distribution in fig. , and the as- sociated small maximum value b = . next, we consider the preferential attachment (pa) mechanism as another baseline model, as it is one of the most fundamental ingredients used in most modeling efforts aimed at describing ci- tation histories of papers. in the pa baseline, references of pro- gressively added citing papers are reassigned according to the pa mechanism (si appendix, section s ). si appendix, fig. s also shows slowly increasing yearly citations by the pa model, explained by the positive feedback effect generated via the pa mechanism. the overall number of citations according to pa baseline for the nine papers in si appendix, fig. s remains small. those are rel- atively young papers in the dataset and their probability to receive citations, according to pa, is reduced by that of older papers. the resulting distribution of b in fig. shows a much smaller range and a well-defined cutoff. it remains to be seen to what extent a recently proposed model for citation histories ( ) is compatible with the sb phenomenon. sbs in science. the occurrence of extreme cases of sbs is not limited to physics. table lists basic information about the papers with the highest b values in the wos dataset (see si appendix, fig. s for their citation histories). this list contains four sbs that were published in the s. consistent with pre- vious studies, we find that many sbs are in the field of physics and chemistry ( ). two papers are, however, in the field of statistics, which failed to be noted before as a top discipline producing sbs. one of them slept for more than one century: the paper by the influential statistician karl pearson, published in in the journal philosophical magazine, shows the relation between prin- cipal component analysis and the minimization chi distance. the other one, published in (therefore sleeping for more than y), introduces the wilson score interval, one type of confidence table . top sbs in science b author(s) title publication, awakening year journal field , freundlich, h concerning adsorption in solutions , z phys chem chemistry , hummers, ws preparation of graphitic oxide , j am chem soc chemistry offeman, re , patterson, al the scherrer formula for x-ray particle size determination , phys rev physics , cassie, abd wettability of porous surfaces , trans faraday soc chemistry baxter, s , turkevich, j a study of the nucleation and growth processes in the synthesis of colloidal gold , discuss faraday soc chemistry stevenson, pc hillier, j , pearson, k on lines and planes of closest fit to systems of points in space , philos mag statistics , stoney, gg the tension of metallic films deposited by electrolysis , proc r soc lond a physics , pickering, su cxcvi.–emulsions , j chem soc, trans chemistry , wenzel, rn resistance of solid surfaces to wetting by water , ind eng chem chemistry , wilson, eb probable inference, the law of succession, and statistical inference , j am statist assoc statistics , langmuir, i the constitution and fundamental properties of solids and liquids. part i. solids , j am chem soc chemistry , moller, c; note on an approximation treatment for many-electron systems , phys rev physics plesset, ms , pugh, sf relations between the elastic moduli and the plastic properties of polycrystalline pure metals , philos mag metallurgy , einstein, a can quantum-mechanical description of physical reality be considered complete? , phys rev physics podolsky, b rosen, n , washburn, ew the dynamics of capillary flow , phys rev physics from left to right, we report for each paper its beauty coefficient b, author(s) and title, publication and awakening year, publication journal, and scientific domain. see si appendix, fig. s for detailed citation histories of these papers. fig. . top disciplines producing sbs in science. we consider papers with beauty coefficient in the top . % of the entire wos database, and compute the fraction of those papers that fall in a given subject category. ke et al. pnas | june , | vol. | no. | a p p li ed p h y si c a l sc ie n c es so c ia l sc ie n c es d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf interval for estimating a proportion that improves over the com- monly used normal approximation interval. the rd (b = , ), th (b = , ), and th (b = , ) top-ranked papers in the wos dataset were published in physical review, but were not ranked as top papers in the aps dataset, suggesting that the bulk of their citations are mainly from journals not contained in the aps dataset. the epr paradox paper (the th), however, is ranked at the top in both datasets. si appendix, tables s and s list basic information about the top sb papers in statistics and mathematics, respectively. publications introducing many important techniques, like fisher’s exact test, metropolis–hastings algorithm, and kendall rank corre- lation coefficient, have high beauty coefficients. we also find nu- merous examples of sbs in the social sciences (si appendix, table s ), in contrast with previous results about their alleged absence ( ). how are sbs distributed among different (sub)disciplines? to further investigate the multidisciplinary character of the sb phe- nomenon, we took advantage of journal classifications provided by journal citation reports (jcr) (thomsonreuters.com/en/ products-services/scholarly-scientific-research/research-management- and-evaluation/journal-citation-reports.html), which classify scien- tific journals into one or more subject categories (e.g., physics, mul- tidisciplinary; mathematics; medicine, general and internal). we first consider only papers published in journals belonging to at least one jcr subject category, and focus on the top . % of papers with highest b values. then, we compute the fraction of those papers that belong to a given subject category. fig. shows the top categories producing sbs. subfields of physics, chemistry, and mathematics are noticeably the top disciplines, consistent with previous studies ( ). some disciplines not previously noted in- clude medicine (internal and surgery), statistics, and proba- bility. particularly interesting is the category multidisciplinary sciences, ranked third, that includes top journals like nature, science, and pnas, because (i) delayed recognition signals that such contributions may be perceived by the academic commu- nity as too premature or futuristic, although it is common ground among academics to speculate that such venues only publish trending topics, and (ii) journals in the multidisciplinary sciences subject category are really more fit to attract publications that become field-defining even decades after their appearance. what triggers the awakening of an sb? a full answer to this question would require a case-by-case examination, but it can be addressed in a systematic way by studying the papers that cite the sb be- fore and after its awakening. to illustrate this strategy, we ex- amine two paradigmatic examples of top sbs. the first is the garfield paper introducing the ancestor of the wos database ( ). this paper slept for almost y, be- coming suddenly popular around . a simple investigation based on cocitations, similar to the one performed in ref. , re- veals that the delayed recognition of the paper by garfield was triggered by later articles by the same author (fig. a). such papers, in turn, were cited by very influential works in two different contexts: (i) the article by kleinberg about the hyperlink-induced topic search (hits) algorithm, which can be considered one pioneering work in network science ( ); and (ii) the paper by seglen on the limitations of the journal impact factor, which historically represents the beginning of the ongoing debate about the (mis)use of citation indicators in research eval- uation ( ). the change in contextual importance of the paper by garfield is further revealed by the frequency of keywords appearing in the titles of its citing papers before and after year (fig. b and c), with the notion of “impact factor” becoming the main recognizable difference. with a similar motivation, the paper by zachary also tops the ranking of sbs coming from the social sciences ( ). this paper was essentially unnoticed for about y, but then became suddenly important in network science re- search after the publication of the seminal paper by girvan and newman, which adopts the social network described in the zachary paper as a paradigmatic benchmark to validate community de- tection methods on graphs ( ) (si appendix, fig. s ). the examples above suggest that a partial explanation behind the sudden awakening of top sbs may lie in the fact that the paper in question is suddenly “discovered” as relevant by an entire com- munity in another discipline. to support this hypothesis, in fig. we divide the papers in the wos dataset into three disjoint subsets with high, medium, and low values of b. for each subset we compute the cumulative distribution for the fraction of citations received by a paper from publications in a discipline (as inferred by the journal of publication) different from that of the cited paper. top sbs are clearly different from the other two categories and are characterized by a typically very high fraction of citations from other disciplines: for about % of the top sbs, as much as % or more of citations are of interdisciplinary nature. a b c fig. . paradigmatic example of the awakening of an sb. (a, blue) citation history of ref. . the three most cocited papers are green, ref. ; cyan, ref. ; and red, ref. . (b and c) clouds of the most frequent keywords appearing in the title of papers citing ref. , published, respectively, before (b) and after (c) year . fig. . interdisciplinary nature of top sbs. cumulative distribution functions of fraction of external citations for the group of (red) top , sbs (b ≥ . ); (blue) from the , st to the top % ( . ≤ b < . ); and (black) the rest (b < . ). the horizontal axis measures for each paper the fraction of its citations that originate from other subject categories. | www.pnas.org/cgi/doi/ . /pnas. ke et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf http://thomsonreuters.com/en/products-services/scholarly-scientific-research/research-management-and-evaluation/journal-citation-reports.html http://thomsonreuters.com/en/products-services/scholarly-scientific-research/research-management-and-evaluation/journal-citation-reports.html http://thomsonreuters.com/en/products-services/scholarly-scientific-research/research-management-and-evaluation/journal-citation-reports.html http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. .sapp.pdf www.pnas.org/cgi/doi/ . /pnas. discussion the main purpose of this work was to introduce a parameter-free method to quantify to what extent a paper is an sb. through a systematic analysis carried out on large-scale bibliographic da- tabases and over observation windows longer than a century, we have shown that our method correctly identifies cases that meet the intuitive notion of sbs. we noticed that our measure is not entirely free of biases: comparing the degree of beauty between papers in different disciplines or ages may be problematic due to differences in the overall citation patterns. despite this limita- tion, we found that papers whose citation histories are charac- terized by long dormant periods followed by fast growths are not exceptional outliers, but simply the extreme cases in very het- erogeneous but otherwise continuous distributions. simple models based on cumulative advantage, although consistent with overall citation distributions, are not easily reconciled with the observed distributions of beauty coefficients. further work is needed to uncover the general mechanisms that may be held responsible for the awakening of sbs. acknowledgments. we thank claudio castellano, filippo menczer, yong- yeol ahn, cassidy sugimoto, and chaoqun ni for insightful discussions, and the american physical society for making the aps dataset publicly available. this work is partially supported by national science foundation (grant sma- ). . egghe l, rousseau r ( ) introduction to informetrics: quantitative methods in library, documentation and information science (elsevier science, amsterdam). . newman mej ( ) coauthorship networks and patterns of scientific collaboration. proc natl acad sci usa (suppl ): – . . sun x, kaur j, milojevi�c s, flammini a, menczer f ( ) social dynamics of science. sci rep : . . guimerà r, uzzi b, spiro j, amaral lan ( ) team assembly mechanisms determine collaboration network structure and team performance. science ( ): – . . wuchty s, jones bf, uzzi b ( ) the increasing dominance of teams in production of knowledge. science ( ): – . . jones bf, wuchty s, uzzi b ( ) multi-university research teams: shifting impact, geography, and stratification in science. science ( ): – . . milojevi�c s ( ) principles of scientific research team formation and evolution. proc natl acad sci usa ( ): – . . radicchi f, fortunato s, castellano c ( ) universality of citation distributions: toward an objective measure of scientific impact. proc natl acad sci usa ( ): – . . wang d, song c, barabási al ( ) quantifying long-term scientific impact. science ( ): – . . uzzi b, mukherjee s, stringer m, jones b ( ) atypical combinations and scientific impact. science ( ): – . . hirsch je ( ) an index to quantify an individual’s scientific research output. proc natl acad sci usa ( ): – . . kinney al ( ) national scientific facilities and their science impact on non- biomedical research. proc natl acad sci usa ( ): – . . davis p, papanek gf ( ) faculty ratings of major economics departments by cita- tions. am econ rev ( ): – . . bornmann l, daniel hd ( ) selecting scientific excellence through committee peer review-a citation analysis of publications previously published to approval or rejection of post-doctoral research fellowship applicants. scientometrics ( ): – . . liu nc, cheng y ( ) the academic ranking of world universities. high educ eur : – . . sarigöl e, pfitzner r, scholtes i, garas a, schweitzer f ( ) predicting scientific success based on coauthorship networks. epj data science ( ): . . petersen am, et al. 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to beauty’ | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . / - . corpus id: dr. ivo pitanguy: strived for a ‘human right to beauty’ @article{bhattacharya drip, title={dr. ivo pitanguy: strived for a ‘human right to beauty’}, author={s. bhattacharya}, journal={indian journal of plastic surgery : official publication of the association of plastic surgeons of india}, year={ }, volume={ }, pages={ - } } s. bhattacharya published medicine indian journal of plastic surgery : official publication of the association of plastic surgeons of india an institution of aesthetic surgery and a one‐man industry. he pioneered procedures that underpinned a burgeoning global industry and dedicated his life to helping people live a better and happier life. he often said, ‘i saw the importance of saving lives and saving functions but it seemed that nobody gave importance to the stigma of deformity and how people suffered with that’. it is this stigma, which kept people away from friends and relatives and made them lesser individuals because of a… expand view on pubmed doi.org save to library create alert cite launch research feed share this paper figures and topics from this paper figure figure lifelong otolith mineralization congenital abnormality eyespot apparatus related papers abstract figures and topics related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue doi: . /j.econlet. . . ier.com/locate/econbase economics letters ( ) – www.elsev changing looks and changing “discrimination”: the beauty of economists daniel s. hamermesh ⁎ university of texas at austin, usa national bureau of economic research, usa forschungsinstitut zur zukunft der arbeit (iza), germany received august ; received in revised form march ; accepted june abstract using candidates' multiple appearances in elections in a professional association with different photographs accompanying ballots, i show that exogenous increases in beauty raise chances of electoral success. the outcomes do not stem from correlations of ascriptive characteristics with unchanging unobserved differences in productivity- enhancing characteristics. © elsevier b.v. all rights reserved. keywords: discrimination; microeconometrics; beauty; professional associations jel classification: j . introduction an immense empirical literature has produced estimates of differences in economic and other outcomes by race, gender, ethnicity, religion, sexual orientation and other ascriptive characteristics. most of these studies have attempted to adjust for other (call them productivity-enhancing) characteristics that might affect the outcome of interest. the pervasive difficulty is that there may well be unobservable productivity-enhancing characteristics that are correlated with the ascriptive characteristic of interest, biasing estimates of the impact of the latter. ⁎ tel.: + ; fax: + . e-mail address: hamermes@eco.utexas.edu. - /$ - see front matter © elsevier b.v. all rights reserved. doi: . /j.econlet. . . mailto:hamermes@eco.utexas.edu http://dx.doi.org/ . /j.econlet. . . d.s. hamermesh / economics letters ( ) – one approach to circumventing this correlation is audit studies-sending probes (resumés, individual testers) to random samples of decision-makers to infer how they react to agents who may be otherwise identical except for the ascriptive characteristic (see mix and struyk, , on race; neumark et al., , on gender; weichselbaumer, , on sexual orientation). their hypothetical nature and the difficulties in inferring what their findings mean (heckman, ) mean that they fail to solve this correlation problem in the context of actual decision-making. several studies (blank, ; goldin and rouse, ; straus et al., ) deal with this issue in real-world behavior by examining cases in which all the information on the ascriptive characteristic is removed. this solves one problem, but it is difficult to claim that the giant leap to no information about the characteristic will generate the same results as changing its distribution with no change in the average amount of information available to agents. no study has examined how actual decisions are altered when individual variation in the information changes with no change in the average amount of information. we do that here in examining the effect of beauty, a characteristic that typically changes very slowly and one that affects outcomes in labor markets and elsewhere through a variety of mechanisms (hamermesh and biddle, ; biddle and hamermesh, ; mulford et al., ; möbius and rosenblat, in press). we infer the impact of changed beauty under the assumption that no other objective characteristic or perception of the individual changes simultaneously. . analytical approach and data the outcome studied is election as an officer of the american economic association. since , the association has conducted two annual four-person elections, for two slots as vice president and two as members of the executive committee. in addition to the ballot, each aea member receives an information sheet containing short biographies and . in.× . in. snapshots of each candidate. all of this information was available beginning with elections for officers for and continuing through the elections for , i.e., a total of candidacies. the consist of only different individuals, including who appear once, who appear twice, who were nominated three times and who appear four times. multiple candidacies are crucial to the analysis. because in most cases a candidate submitted a different picture each time s/he appeared on the ballot, the same candidate presented the voters with a different image in each candidacy. even though the same person is on the ballot, the information provided to voters by the candidates' appearance may vary for this reason. moreover, because his/her competition changes, even with the same picture a candidate's appearance relative to competitors can change. the goal is to analyze whether a candidate's appearance affects his/her electoral chances and how an individual's changed appearance affects his/her chance of victory. we cannot determine whether voters react to the person's appearance as a signal of productivity, or whether voters have a preference for good looks independent of any signal. with over economists voting in each of the elections, however, only a small minority knows the candidates personally. professional reputation, including that conveyed in the written material accompanying the ballot, may matter, as may the information contained in the photograph. by examining multiple candidacies, we can, however, infer whether changing one's to my knowledge, klein and rosar ( ) is the only study even to consider one-time appearances of candidates in actua elections (rather than in hypothetical examples). l mythical anecdotal evidence that this is the case is provided by eddie murphy's “white like eddie” saturday night live routine in the early s. several economists argued that this study would be impossible to conduct, since the beauty measure would be identically zero. table beauty evaluations, individual and composite ( aea candidacies) individual ratings average s.d. standardized minimum maximum male . . − . . male . . − . . male . . − . . female . . − . . average standardized rating (rij) . − . . relative average standardized rating (r*ij) . − . . d.s. hamermesh / economics letters ( ) – appearance affects how decision-makers (the voters) react to changes in the ascriptive characteristic beauty, holding constant other changes between ballots. as shown by donald and hamermesh (in press), the probability of victory in these elections is significantly positively affected by a candidate's scholarly impact (citations in journal articles, computed from the social science citation index)—his/her share of the citations received by the four candidates in the election, by being a woman and by previously or currently holding a high-level government position. in addition to these measures, we also include other variables in describing the outcome: affiliation (top school, or nonacademic), race (african–american), field (theorist/econometrician), future nobel prize winner and years since receiving the highest degree (essentially a proxy for age). to examine the role of beauty in these elections, we had the photographs rated independently by each of four observers. we needed to make sure that the raters did not know any of the candidates, but that they were familiar with whatever gestalt academic economists may typically present. to deal with this difficulty, i employed four entering first-year economics phd students, all of whom had attended undergraduate institutions in the united states, as raters. to reflect the membership of the association, three were male and one female. each was asked to rate the attractiveness of the candidate in each picture on a scale from (top) to (bottom) and to try to maintain an average rating of (without re-examining previously rated photos). i assume that the raters' perceptions represent the perceptions of the voters who confronted the photographs and the ballots. table presents statistics describing the ratings. there are substantial differences among raters in the moments of the distribution of ratings. accordingly, each rater i's scores were normalized to yield standardized scores, the minima and maxima of which are shown in the final two columns of the first four rows. the six pair-wise correlations of these scores range from . to . , with cronbach's α equaling . . these statistics indicate a very slightly lower concordance among the raters than has been observed in other studies (e.g., pfann et al., ), possibly because the tiny photographs induce more noise than usual. nonetheless, there is substantial agreement among raters: all the pair-wise correlation coefficients are highly significant statistically. the four standardized ratings were averaged to obtain an average standardized rating, rij, for each candidate i in election j. a candidate's beauty relative to the entire history of candidates is unlikely to be table multinomial multiple response estimates of the impacts of several independent variables on the probability of election, elections – (n= )a ind. var. ( ) ( ) ( ) ( ) ( ) citation share . ( . ) . ( . ) . ( . ) . ( . ) . ( . ) female . ( . ) . ( . ) . ( . ) . ( . ) . ( . ) relative average standardized beauty . ( . ) . ( . ) relative average standardized beauty n . ( . ) . ( . ) relative average standardized beauty b − . ( . ) − . ( . ) female*relative average standardized beauty − . ( . ) female*relative average standardized beauty n − . ( . ) female*relative average standardized beauty b . ( . ) log l − . − . − . − . − . a standard errors in parentheses here and in table . also included in each equation are indicators of whether the candidate had held or currently holds a high-level government position, whether he/she was in a top-five economics department, whether he she was not an academic, would eventually win a nobel prize, was a theorist or econometrician, was an african–american, and a continuous measure of years since phd (or othe terminal degree). coefficients using standard logit techniques are very similar to the correct ones displayed in table . d.s. hamermesh / economics letters ( ) – r relevant for his/her electoral chances. rather, and analogous to our treatment of citations, it is his/her relative beauty in the election that may affect the outcome. accordingly, for each candidacy, we form: rij* ¼ rij−rdj; ð Þ where r·j is the average of the average standardized beauty of all four candidates in the jth election. we focus on the impact of r*ij on the probability of election. . effects of beauty in elections, all candidacies – the fraction of winners among the half of the candidacies with above-average beauty is . (standard error of mean= . ); among the half of the candidacies with below-average beauty, the winning fraction is only . (standard error of mean= . ). this simple cut of the data by whether the candidate's beauty is above or below the average for his/her competitors suggests that beauty does matter in these elections. to examine this further, and as a baseline for comparing the results estimated over the multiple candidacies, table presents estimates of the impact of relative average standardized beauty on a candidate's chance of victory. because there are two winners, standard probit/logit estimation methods cannot be used. while a conditional logit that used the six ( c ) possible pairs of candidates in an election as observations would solve the problem of two winners, the set-up violates the assumption of the independence of irrelevant alternatives in the conditional logit (the absence of correlation of the unobservables across pairs). to deal with this difficulty, the coefficients presented in table are based on the multinomial multiple response estimator developed in donald and hamermesh (in press). we assume that the errors follow the extreme value distribution, so that the index indicating a candidate's strength is estimated under assumptions analogous to those underlying ordinary logit estimation. the first column in table shows estimates of the basic equation determining the probability of election. only the parameter estimates on citation share and female are presented: the estimated coefficients on most of the other variables–being in a top economics department, not being an academic, d.s. hamermesh / economics letters ( ) – being a future nobelist, a theorist or econometrician, an african–american, and years of post-degree experience–had no statistically or economically significant impacts. having held a high-level government position has a statistically significant positive effect but is not of interest here. the second column adds r*ij to the equation. in this cross section, the impact of beauty on the probability of being elected is positive with a t-statistic greater than one, although not statistically significant at conventional levels. the estimated effect of being better looking than the other candidates is not small: at one standard deviation below the mean beauty in an election, an identical candidate has a chance of . of being elected; at one standard deviation above the mean, the chance is . . column ( ) includes an interaction between r*ij and gender, based on previous work (hamermesh and biddle, ) that indicated that the impacts of beauty on outcomes are greater for males. the implications of the results are remarkable: in this sample, a woman's looks relative to those of the other candidates in an election have absolutely no effect on her electoral chances. among men, however, the impact is substantial and approaches statistical significance. given the overriding importance of gender in these elections ( % of female candidates are elected), it is perhaps unsurprising that female candidates' beauty has little marginal effect. columns ( ) and ( ) explore asymmetries in voters' responses to the candidates' relative beauty. the estimates in column ( ) demonstrate that moving further below the average looks in an election has no impact on one's chances of winning, but it does pay to be increasingly better looking than one's competitors, and the effect is large and statistically significant. moreover, as implied by the estimates in column ( ), the asymmetry only matters for male candidates. being below or above average in looks has no impact on female candidates' victory probabilities. . using multiple candidacies to infer the effects of beauty the cross-section results in section suggest that even economists pay attention to beauty when making decisions. for whatever reason, this ascriptive characteristic matters in determining an outcome that we assume is the result of maximizing choices made by a set of presumably rational agents. the question is whether changes in the characteristic, holding constant other changes that might affect a candidate's electoral chances, alter the outcomes. to examine this possibility, we estimate models over the candidates ( candidacies) who appear in two or more elections. variations in their perceived beauty are almost surely exogenous to the election outcomes: it is extremely difficult to argue that the candidates learn about the role of beauty from their prior electoral experiences and submit more appealing pictures on subsequent ballot appearances. indeed, in their first electoral outing rij (r*ij) averaged . ( . ); in their final electoral outing, the second for most of the sample members, rij (r*ij), averaged − . (− . ). the differences in average beauty between a candidate's first and final outings are statistically zero, but they do decrease, contrary to what one would expect if the candidates submitted pictures based on their learning about the role of beauty in the electoral process. columns ( ) and ( ) of table list estimates of the same equations as in columns ( ) and ( ) of table . (with the elimination of nearly half the sample and thus no adding-up constraint on predicted probabilities, ordinary logit estimation becomes appropriate.) the standard errors are robust, accounting in a reduced sample that excludes the female candidacies, the estimated impact of beauty among male candidates is larger than the estimates in column ( ) and is significant statistically. table logit and conditional logit estimates of the determinants of the probability of election, multiple candidacies in elections – a ind. var. ( ) ( ) ( ) ( ) ( ) logit with robust standard errors cond. fe logi citation share . ( . ) . ( . ) . ( . ) . ( . ) . ( . ) female . ( . ) . ( . ) . ( . ) relative average standardized beauty . ( . ) . ( . ) . ( . ) . ( . ) relative average standardized beauty n . ( . ) relative average standardized beauty b − . ( . ) log l − . − . − . − . − . n (candidacies) n (candidates) a also included in columns ( )–( ) are indicators of whether the candidate had held or currently holds a high-level government position, where he/she was in a top-five economics department, whether he she was not an academic, would eventually win a nobel prize, was a theorist o econometrician, was an african–american, and a continuous measure of years since phd (or other terminal degree). the logit in column ( ), and the conditional logit in column ( ) include only the variables listed and the measure of years since degree. this last changes differentially across observations because of differences in the time intervals between candidates' appearances on the ballot. there is evidence, however, of extremely high autocorrelation in an individual's looks, even over many decades (hatfield and sprecher, , pp. – ). d.s. hamermesh / economics letters ( ) – t r for the clustering of observations. the parameter estimates and their implications are very similar to those estimated over the entire sample. the effect of r*ij is about the same (although the statistical significance is lower). again we observe an asymmetric impact of r*ij, with a statistically significant advantage to being increasingly better looking than the average candidate, but no disadvantage to being increasingly worse looking. in column ( ), the same specification as in column ( ) is re-estimated over the reduced sample of people who won at least one election and lost at least one. this sample is quite small, only candidacies, so that sample size limitations lead us to expect a reduction in statistical significance compared to the earlier estimates. despite that, the t-statistic exceeds one in absolute value, and the point estimate of the marginal impact of an increase in beauty in this sub-sample is larger than in the entire sample or in the sample of all multiple candidacies. for comparison to other estimates, column ( ) presents logit estimates over this same sub-sample of candidacies, including only those variables that change between candidacies—citation share, relative average standardized beauty and years of post-degree experience. again there is fairly little change in the estimated impact of beauty on electoral outcomes compared to the other specifications and (larger) samples. the parameter estimate is positive and the t-statistic still exceeds one. the conditional fixed-effect logit estimates are based on variations within the candidates who appear in elections and who lost at least one election and won at least one. the average duration between appearances on the ballot is . years, with a minimum of year and a maximum of years. in many cases, these durations may be sufficient to allow the candidate's underlying beauty to change slightly. more important, however, with different photographs on the ballots voters' perceptions of the candidates' d.s. hamermesh / economics letters ( ) – looks, as proxied by the raters' perceptions, will vary across a candidate's appearances. the within- candidate variance of relative average standardized beauty is % of the total variance in this measure. the estimates in the final column of table show the impacts of changes in candidates' citations and beauty relative to the other three candidates included in the elections in which they appear. all of the variation is within the candidate (relative to the changing variation among the competing candidates). even with this stringent test we find roughly the same effect of changes in the candidate's relative beauty on his/her chances of winning an election as we have seen in the other estimates. moreover, the standard error of the parameter estimate remains roughly what it was (conditional on the diminution of the sample size). the mean probability of election in this reduced sub-sample is . . when r*ij drops by one standard deviation, the electoral probability falls to . ; when it increases by one standard deviation, it rises to . . these effects are not small and are nearly identical to those in the cross-section estimates over the entire sample. . conclusions and implications this study has not shown that there is discrimination against bad-looking people. rather, i have demonstrated that a particular real-world outcome becomes more favorable for the same person when perceptions of his/her looks improve exogenously. when sample sizes are reduced sufficiently, the estimated impacts of beauty are no longer significant statistically, but the estimated impacts of perceptions of beauty remain unchanged and the uncertainty about the estimates increases solely in proportion to the decrease in sample sizes. these findings should strengthen the conclusion, both about beauty and by inference about other ascriptive characteristics such as race or gender, that even with the same average amount of information it is relative position that is important. the characteristic itself, not any correlation with unobservable productivity-enhancing characteristics, generates the apparent impacts on outcomes of interest. acknowledgements stephen trejo gave helpful comments on a previous draft and mark pocock provided research assistance. references biddle, j., hamermesh, d., . beauty, productivity, and discrimination: lawyers' looks and lucre. journal of labor economics , – . blank, r., . the effects of double blind versus single blind reviewing: experimental evidence from the american economic review. american economic review , – . the substantial increase in the estimated effect of scholarly productivity–the share of citations–is surprising. it does not stem from non-linearity in the impact of citations: in the cross-section estimates in table , a nonlinear term in this measure is insignificantly different from zero. it may arise from the fact that within-candidate variation in the citation share is only % of the total variance. re-estimating all the models in table by substituting rij for r*ij does not alter the conclusions about the importance of beauty. indeed, the statistical significance of coefficients on rij is greater than that of the estimates in table in al specifications. this similarity is not surprising, as the within-candidate standard deviation of average standardized beauty accounts for % of the total variation in this measure. l d.s. hamermesh / economics letters ( ) – donald, s., hamermesh, d., in press. what is discrimination? gender in the american economic association, – . american economic review , forthcoming. mix, m., struyk, r., . clear and convincing evidence: measurement of discrimination in america. urban institute press, washington. goldin, c., rouse, c., . orchestrating impartiality: the impact of ‘blind’ auditions on female musicians. american economic review , – . hamermesh, d., biddle, j., . beauty and the labor market. american economic review , – . hatfield, e., sprecher, s., . mirror, mirror…. state university of new york press, albany, ny. heckman, j., . detecting discrimination. journal of economic perspectives , – . klein, m., rosar, u., . physische attraktivität und wahlerfolg: eine empirische analyse am beispiel der wahlkreiskandidaten bei der bundestagswahl [physical atractiveness and electoral success: an empirical analysis of the example of electoral district candidates in the parliamentary election]. politische vierteljahresschrift , – . möbius, m., rosenblat, t., in press. why beauty matters. american economic review , − . mulford, m., orbell, j., shatto, c., stockard, j., . physical attractiveness, opportunity and success in everyday exchange. american journal of sociology , – . neumark, d., bank, r., van nort, k., . sex discrimination in restaurant hiring: an audit study. quarterly journal of economics , – . pfann, g., biddle, j., bosman, c., hamermesh, d., . business success and businesses' beauty capital. economics letters , – . straus, s., miles, j., levesque, l., . the effects of videoconference, telephone, and face-to-face media on interviewer and applicant judgments in employment interviews. journal of management , – . weichselbaumer, d., . sexual orientation discrimination in hiring. labour economics , – . changing looks and changing “discrimination”: �the beauty of economists introduction analytical approach and data effects of beauty in elections, all candidacies – using multiple candidacies to infer the effects of beauty conclusions and implications acknowledgements references [pdf] minimally invasive surgery in orthopaedics. small is beautiful? | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. corpus id: minimally invasive surgery in orthopaedics. small is beautiful? @article{yeung minimallyis, title={minimally invasive surgery in orthopaedics. small is beautiful?}, author={s. yeung}, journal={hong kong medical journal = xianggang yi xue za zhi}, year={ }, volume={ }, pages={ - } } s. yeung published medicine hong kong medical journal = xianggang yi xue za zhi with the blooming of minimally invasive procedures in surgical specialties, many orthopaedic subspecialties have been evolving along such lines. despite the apparent paradox that many orthopaedic implants are quite bulky to start off with, different methods have been adopted to insert them safely with the least possible trauma. altering time-honoured incisions and surgical techniques has often been helpful. the industry is also very keen to re-design implants for this purpose and has… expand view on pubmed hkmj.org save to library create alert cite launch research feed share this paper citations view all topics from this paper wounds and injuries orthopedics microscope, surgical endoscopes minimally invasive surgical procedures entity name part qualifier - adopted specialties, surgical one citation citation type citation type all types 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s. yip, y. lam, m. chan, j. shu, k. c. lai, y. c. so medicine hong kong medical journal = xianggang yi xue za zhi pdf save alert research feed carpal ligament injuries with acute scaphoid fractures – a combined wrist injury t. wong, t. yip, w. wu medicine journal of hand surgery save alert research feed ... ... related papers abstract topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue kant, proust, and the appeal of beauty kant, proust, and the appeal of beauty the harvard community has made this article openly available. please share how this access benefits you. your story matters citation moran, richard. . kant, proust, and the appeal of beauty. critical inquiry ( ): - . published version doi: . / citable link http://nrs.harvard.edu/urn- :hul.instrepos: terms of use this article was downloaded from harvard university’s dash repository, and is made available under the terms and conditions applicable to other posted material, as set forth at http:// nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of- use#laa http://osc.hul.harvard.edu/dash/open-access-feedback?handle=&title=kant,% proust,% and% the% appeal% of% beauty&community= / &collection= / &owningcollection / &harvardauthors=ac a a d e be d db b c&departmentphilosophy http://nrs.harvard.edu/urn- :hul.instrepos: http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa kant, proust, and the appeal of beauty richard moran a familiar feature of the history of modern aesthetics is the cycle of suspicion and defensiveness connected with the idea of beauty, as though its very appearance suggested something exaggerated, something requir- ing deflation, which then provokes a certain polemical stance on the part of both its defenders and detractors. people who would not be tempted by a reductive account of other concepts (for example, of thought, or desire, or action), may still feel that beauty has to be shown to be illusory or explained as a mere guise of some other force or quality altogether in the end. one might, for instance, have reasons to be suspicious of pleasure itself, its role in culture, or the exaggerated claims for it, or one may have metaphysical scruples deriving from the idea that beauty can be no prop- erty of things in themselves but can only be a projection of our own sen- sibilities upon the world. in different ways, then, there can seem to be a certain extravagance built into the notion of the beautiful itself, as though it were internal to its invocation that it claims more for itself than it can deliver on. familiar as these thoughts are, however, their import is far from clear. the thought about projection, for instance, need not be any more skeptical than the parallel claims that are made about secondary qualities generally, the supervenience of which on our sensory dispositions is not i had the pleasure of presenting some of this material at a warren quinn conference at the university of california, los angeles, where i benefitted from comments by franklin bruno; at a sawyer seminar at the university of chicago, hosted by david wellbery and james conant; in a series of seminars at johns hopkins university hosted by michael fried; at a workshop on philosophy and literature and film organized by susan wolf at the university of north carolina, chapel hill; and at the new york university conference on modern philosophy and aesthetic judgment, organized by beatrice longuenesse, john richardson, and don garett, where i had helpful comments from rebecca kukla. the paper benefitted from all these occasions, particularly from the hosts in question, as well as from audiences at the university of illinois, university of chicago, stanford university, and the university of illinois, urbana- champaign. for conversations either on those occasions or much earlier i am grateful to stanley cavell, fred neuhouser, alexander nehamas, paul guyer, jonathan lear, lanier anderson, joshua landy, katalin makkai, meredith williams, robert pippin, wayne martin, brent kalar, michael williams, hannah ginsborg, katalin makkai, thomas teufel, melissa merritt, tim scanlon, and david sussman. at early stages of the project conversations with martin stone helped orient me in the topic, and toward the end of it conversations with arata hamawaki were crucial to giving shape to the story. the paper is dedicated to the memory of mary mothersill. critical inquiry (winter ) © by the university of chicago. - / / - $ . . all rights reserved. usually taken to be equivalent to their being simply unreal or to be incom- patible with the idea that in calling the sky blue one is claiming something beyond one’s subjective experience. the idea of beauty, however, can lend itself to repudiation of an- other kind, as being a perfectly useless concept, the residue of pieties we can no longer take seriously. and in the life of an individual, something in the idea of beauty makes possible its characteristic forms of disillu- sion and not merely disappointment. one may be disappointed with one’s experience of ordinary pleasures, finding in them less than one hoped to find or even losing one’s taste altogether for certain of them. in relation to beauty, however, there is room for the possibility of not just disappointed expectations but disillusionment and, with that, re- pudiation of the very idea of beauty, as though the very idea were a form of mystification. what i take this to show is that the very possibility of such skepticism is testament to the fact that there is something addi- tional it would make sense to reject in the claim of beauty, something beyond the thought that something is a special source of pleasure. it is only against the background of something supposedly beyond ordinary pleasure and pain that there is the possibility of rejecting its claim, finding it perhaps quaint or hollow. with regard to beauty, there seems to be room for a different kind of rejection of its reality or genuineness . consider this well-known passage: attend to palladio and perrault, while they explain all the parts and proportions of a pillar. they talk of the cornice, and frieze, and base, and entablature, and shaft, and architrave; and give the description and position of each of these members. but should you ask the description and position of its beauty, they would readily reply, that the beauty is not in any of the parts or members of a pillar, but results from the whole, when that complicated fig- ure is presented to an intelligent mind, susceptible to those finer sensations. till such a spectator appear, there is nothing but a figure of such particular dimensions and propor- tions: from his sentiments alone arise its elegance and beauty. [david hume, an inquiry into the principles of morals (middlesex, ), p. ] here hume seems to derive a claim about the subjectivity of beauty from the common fact of the constitution of one set of properties by another. palladio could just as rightly say that the strength of the pillar is not in any of its parts or members, but it would hardly follow from this that its strength was somehow unreal or a mere projection of the sentiments. r i c h a r d m o r a n is the brian d. young professor of philosophy at harvard university. he is the author of authority and estrangement: an essay on self- knowledge. he is completing self-expression and the modes of address, a book on intersubjectivity in the acts of speaking and telling. critical inquiry / winter or the thought that it can’t be and never was all that it presents itself as being. there is, however, another related set of reasons why the concept of beauty is subject to forms of skepticism peculiar to it. far more than most other concepts of philosophical interest the idea of beauty has a well- developed cultural mythology that is as much a part of it as are any theories of it that have been proposed. indeed, the competing philosophical theo- ries themselves have little point taken in isolation from the various depic- tions of the encounter with beauty that make their appearance throughout the western tradition, from plato to the christian era, through romanti- cism, modernism, and whatever comes after that. part of what i mean by mythology is that these ideas are something like a common cultural re- source, that they inform our actual experience and thinking about the thing in question, and are for that reason to be seen as belonging to the concept itself, whether part of its literal or figurative content. there needn’t be anything elaborate in such depictions, so let me begin with some simple examples, neither original nor exhaustive. so, for instance, beauty is commonly associated with mystery, as something that beckons but also withdraws and withholds, something whose nature belongs with appearing but that also presents itself as containing in itself more than is apparent. while it belongs to the sensory, to the realm of feeling, and is in that sense fully present to experience, at the same time it partakes of con- cealment in ways not shared by the rest of sensory life. a familiar trope of beauty is that of something not just pointing beyond itself but as harboring a secret or posing a question to be answered. and this is itself one of the classic settings for the disappointment and disillusion associated with beauty. a running theme in marcel proust’s swann’s way, for instance, is the repeated frustration of the narrator in his attempts to penetrate the secret that seems to be held by the scenes he finds most enthralling, which seem to pose a question that he cannot formulate, let alone answer. the beautiful not only beckons but also charms, enthralls, and other- . or compare beauty with ordinary pleasure and pain with regard to the possibility of error. given the appearance of pleasure or pain, it is hard to imagine a place for a further question about its genuineness or reality. given the appearance of beauty, we may later come to question its genuineness or reality and perhaps come to the conclusion that the appearance of beauty here was a false one. it didn’t hold up to scrutiny; its promise was false or meretricious. if this is right, then beauty, unlike pain or pleasure, is not a property whose esse is percepi. and it raises the question of what sort of scrutiny it is that could show that an apparent beauty was in fact false, or what further question that appearance would have to answer to show itself to be real. (kant, of course, takes up such questions in terms of the conditions for a pure judgment of taste.) . here he is, early in the story, after one of his recurrent moments of despair of ever being equal to his literary vocation: richard moran / beauty wise captivates its beholder. the tradition of describing something beau- tiful in such grammatically active aesthetic verbs as compelling, enticing, or appealing is both part of ordinary speech and a way of depicting the en- counter with the beautiful object as somehow two-sided, involving an active element on the side of the object itself to which the beholder actively responds. this can be a perfectly anodyne way of talking, of course, and the metaphorical residue thoroughly effaced and without force, but even as dead metaphor such discourse registers a difference from other response- dispositional concepts, such as red, and highlights the idea of a type of response that the beautiful object calls for or makes appropriate. whether we think of the active verbs in this context as simply dead metaphors or as the result of projection on the part of the beholder, their presence also suggests a difference in the kind of response the beholder may feel obliged to summon in the face of the object, a responsiveness of a different kind from that involved in making correct color judgments. along the same lines, though less anodyne, the use of such active aesthetic vocabulary applied to the object belongs to the tradition of seeing something animated or animating in the experience of the beautiful or in the actual thing found beautiful. here again, immanuel kant is no stranger to this tradition, both in the association of beauty with the arousal of the “quickening” powers of the mind (most especially and obscurely the “free play of the cognitive powers [imagination and understanding]”) and more generally in the con- then, quite independently of all these literary preoccupations and in no way connected with them, suddenly a roof, a gleam of sunlight on a stone, the smell of a path would make me stop still, to enjoy the special pleasure that each of them gave me, and also because they appeared to be concealing, beyond what my eyes could see, something which they invited me to come and take, but which, despite all my efforts, i never managed to discover. since i felt that this something was to be found in them, i would stand there, motionless, looking, breathing, endeavouring to penetrate with my mind beyond the thing seen or smelt. [mar- cel proust, swann’s way, trans. c. k. scott moncrieff and terence kilmartin (new york, ), pp. – ; hereafter abbreviated sw] . “in this glum desert, suddenly a specific photograph reaches me; it animates me, and i animate it. so that is how i must name the attraction which makes it exist: an animation (roland barthes, camera lucida: reflections on photography, trans. richard howard [london, ], p. ). the connection of beauty with the ideas of life-likeness and animation is thematic in elaine scarry’s on beauty and being just and is part of her account of the thought that the beautiful object calls for certain forms of treatment, the way a living thing would: “the almost aliveness of a beautiful object makes its abrasive handling almost unthinkable” (elaine scarry, on beauty and being just [princeton, n.j., ], p. ; see also pp. – , ). critical inquiry / winter nections drawn between beauty and the purposive in living nature, be- tween aesthetic and teleological judgment. in many canonical representations, the encounter with beauty takes place against the background of its transience and perishability. “death is the mother of beauty,” wallace stevens says at the end of “sunday morn- ing,” and in this he is giving voice to a long tradition of thinking of beauty alongside its relation to time and destruction, which is also part of thinking of it as essentially fleeting, eluding one’s grasp, impossible to possess. plea- sures quite generally may be fleeting, but talk of beauty makes it almost a sign of its own relation to death, either as submitting to it or promising to outlast it. this is connected with the sense of the special possibilities of damage there are with respect to beauty: it not only fades, like other plea- sures, but is also the sort of thing that can be defaced or disfigured. beauty is subject to the possibility of ruin and not just interruption or decline. the characteristic relation of beauty to special possibilities of loss expresses itself both in the association of beauty with ideas of irreplaceability, taking beauty out of the ordinary economy of exchange and substitution (and hence toward the possibility of absolute, unrecoverable loss), and also to the tradition of thinking of the experience of beauty as promising to defeat death or defeat time somehow. that is, beauty also figures in the guise of something redeeming or compensating for the finitude or perishability of other values, particularly as contrasted with other pleasures. this part of the myth of beauty is surely part of what is repudiated in some of the forms of skepticism about beauty mentioned earlier, the thought that the sheer contingent existence of beauty in the world somehow makes up for other failings or losses or shows them to be less real than beauty itself. in their very different ways, both kant and proust take the improbable ap- pearance of beauty in our experience of the world as requiring explanation in terms of something else, as pointing to either our fitness for moral life and the world’s possible conformity to moral good, as in kant, or, as a kind of liberation from subjectivity in proust, from the natural solipsism of desire as appetite. finally, both in philosophy and elsewhere, beauty is associated with enhanced stakes for the question of the communicability of experience, . immanuel kant, critique of judgment, trans. werner s. pluhar (indianapolis, ), § , pp. , ; hereafter abbreviated cj. . wallace stevens, “sunday morning,” selected poems, ed. john n. serio (new york, ), p. . . for a sophisticated critique of the redemptive claims of art, rather than beauty generally, see leo bersani, “‘the culture of redemption’: marcel proust and melanie klein,” critical inquiry (winter ): – . richard moran / beauty not only as problematizing such communication but as making more ur- gent the question of how much can be communicated one to another and the situations in which its success can be peculiarly fraught or urgent. beauty may lay no exclusive claim to the idea of the ineffable in experience, but it is surely central to it, and this thought relates beauty both to diffi- culties in the notion of communication itself, to the incurably private in experience, and to the specific needs of the shareability of experience that arise in aesthetic contexts. the issue of communication includes but is not restricted to the question of finding we agree in our particular aesthetic judgments and also includes the conditions for various forms of disagree- ment. the relation to beauty can form communities of people and can also isolate them from each other. nothing is more characteristic of the aes- thetic than being bored or repelled by what enthralls someone else. and if being gripped by beauty can sometimes make possible certain forms of communication that were not previously imagined, it also belongs to its experience to tend toward obsession, absorption, and the walling-off of one consciousness from others. while his systematic, critical concerns dictate much of the place that aesthetic judgment occupies in his philosophy, kant is in one way or an- other responsive to all of this and more in the broader myth of beauty, and several of his central claims can be understood as attempts to render parts of it intelligible in more abstract and systematic terms. (the place of beauty in kant’s philosophy is in these ways part of but not restricted to what he is responding to in romanticism.) here i will be concentrating on his fram- ing of the central paradox of the judgment of beauty, how it is that some- thing based on the purely subjective experience of pleasure and without the support of concepts or rules could claim universal validity for itself. while this paper does present itself as an interpretation of a central strain in kant’s account of the judgment of beauty, there is much in his argument to which i will give scant attention (particularly the role of transcendental psychology and the “freeplay of the faculties”); and in addition i will argue for departures from his account at some central places, so central that some may wonder how much of kant remains in the story. the point of reading kant in connection with proust has not been simply to use the novelist as a corrective to the philosopher, although the paper is indeed written from the perspective that it should be beyond question that marcel proust is at least as decisive a thinker about the nature of beauty as is . see especially stanley cavell, “aesthetic problems of modern philosophy,” must we mean what we say? a book of essays (cambridge, ), and arata hamawaki, “kant on beauty and the normative force of feeling,” philosophical topics (spring–fall ): – . critical inquiry / winter immanuel kant. it is just as much the point, however, that proust can help us to see what is deeply right, or nearly so, in kant’s outlook, as well as what kant wants from the concept of beauty, even if it can’t be had exclusively from the materials he allows himself. a judgment of taste determines its object in respect of our liking (beauty), [but] makes a claim [anspruch] to everyone’s assent, as if it were an objective judgment. to say, this flower is beautiful, is tantamount to a mere repetition of the flower’s own claim [anspruch] to everyone’s liking. the agree- ableness of its smell, on the other hand, gives it no claims [ansprüche] whatever; its smell delights . . . one person, it makes another dizzy. in view of this . . . must we not suppose that beauty has to be considered a property of the flower itself, which does not adapt itself to differ- ences in people’s heads and all their senses, but to which they must adapt themselves if they wish to pass judgment on it? [cj, § , p. ; trans. mod.] sagen: diese blume ist schön, heisst eben so viel, als ihren eigenen anspruch auf jedermanns wohlgefallen ihr nur nachsagen. anspruch: claim, title, right, demand. ansprechen: speak to, accost, address, appeal to. ansprechend: pleasing, attractive, appealing, engaging. many writers on aesthetics recognize a special question about the nor- mativity of the judgment of beauty, insofar as this is different from the judgment of something as agreeable or pleasant. in a familiar sense there is a normative dimension to any empirical judgment, in that there are con- ditions for going right or going wrong, and if one is in the business of making such judgments one is obliged to conform one’s judgment to the conditions of correctness. this much applies to the judgment of some- thing as red as much as it does to judging it beautiful. but although we can specify the conditions necessary for someone to be in a position to make a correct color judgment (adequate or normal lighting, attending carefully enough, and so on), they do not, as it were, commend anyone to get them- selves into those conditions. the world is full of opportunities for correct empirical judgments to which we may be legitimately indifferent. and the richard moran / beauty red or square objects around us are not awarded that title as a term of praise or admiration. the idea of beauty, however, according to kant and much of the tradition, does not simply specify the conditions one must satisfy in order to make such a judgment correctly but also involves the claim that the object in question merits this response, that it deserves one’s attention and that anyone attending to it properly ought to respond with pleasure and admiration. these are dimensions of normative assessment that are not part of the concept of an object’s being red or square. the idea of beauty may well contain conditions for correct judgment, just as there are with the judgment of color (and kant has his well-known specifications of these in terms of disinterest, attention to form, and so on), but these do not exhaust the normative dimension of the judgment of beauty. for with regard to beauty the idea of the object meriting or calling for a response from us seems to be what is primary, a norm of responsiveness that is prior to the obligation the response shares with ordinary empir- ical judgments of conforming to certain conditions for correct judg- ment. and any particular form of normative requirement—whether moral, prudential, or cognitive— brings its own particular possibilities of falling short, of failure to conform to its own demands. both kant and proust are concerned with a sense of requirement or obligation in connection with the experience of the beautiful and see this as the primary difference between the beautiful and the (merely) agreeable or pleasant. for kant, the requirement is described as something directed outwards, toward other people, in that we speak of the beautiful as such only when we are not speaking merely for ourselves but are prepared to demand the agreement of all others. many things may be charming and agreeable to him; no one cares about that. but if he proclaims something to be beautiful, then he requires the same liking from others; he then judges not just for him- self but for everyone, and speaks of beauty as if it were a property of things. that is why he says: the thing is beautiful, and does not count on other people to agree with his judgment of liking on the ground that he has repeatedly found them agreeing with him; rather he de- mands [fordern] that they agree. he reproaches them if they judge differently, and denies that they have taste, which he nevertheless de- mands of them, as something they ought to have. [cj, § , pp. – ] the language here couldn’t be more emphatic as to its imperatival quality, but insofar as the demand in question is a demand to others (however hypothetical their presence) that they agree in liking the beautiful object, it raises the question of what the basis could be for such a demand, what critical inquiry / winter there is in this demand that another person might be bound to respect. that is, what could it be that places this person in a position to issue such a demand? it cannot be simply his personal authority, a possibility that kant in any case is at great pains to reject. rather, it would seem that, as with the issuing of moral or prudential demands, the person is in a position to make such a demand only because he recognizes himself as subject to a requirement here, to be under an obligation. the source of the outward- directed requirement on others in these cases can only be his own ac- knowledgment of the obligations of the moral law or the maxims of practical reason. but in the case of someone prepared to require the agree- ment of all others in his liking or pleasure in connection with something he finds beautiful, it is difficult to see what could ground his own sense of requirement or obligation with respect to that thing such that it could be the basis for the imperative he directs to others. in one sense this question of the normative force of this demand di- rected to others is not a problem for proust; he does not understand the beautiful in terms of a demand for universal agreement and in fact is more inclined to relate the validity of the claim of the beautiful to what is indi- vidualizing and even potentially isolating in such an experience. but if he does not have to face the question of what the source of the demand for agreement from others could be, he does at the same time insist on a sense of obligation or requirement as characteristic of the experience of the beautiful. here is the young marcel, early in the story, saying goodbye to his beloved hawthorns, whose claim on him he will retain through all the volumes of in search of lost time. that year my family fixed the day of their return to paris rather earlier than usual. on the morning of our departure . . . my mother, after searching everywhere for me, found me standing in tears on the steep little path close to tansonville, bidding farewell to my hawthorns, clasping their sharp branches in my arms. . . . “oh, my poor little hawthorns,” i was assuring them through my sobs, “it isn’t you who want to make me unhappy, to force me to leave you. you, you’ve . kant uses a variety of terms to express the sense of something required or exacted in the judgment of beauty. the verbs that get variously translated as “require,” “demand,” and so on include fordern, verlangen, ansinnen (“we must begin by fully convincing ourselves that in making a judgment of taste [about the beautiful] we require [ansinnen] everyone to like the object” [cj, § , p. ] and zumuten (“for as to the agreeable we allow everyone to be of a mind of his own, no one requiring [zumuten] others to agree with his judgment of taste. but in a judgment of taste about beauty we always require others to agree” [cj, § , p. ]). see paul guyer, kant and the claims of taste (cambridge, mass., ), pp. – for a helpful discussion. i have also been instructed on this topic by a conversation with rolf-peter horstmann, for which i am grateful. richard moran / beauty never done me any harm. so i shall always love you.” and, drying my eyes, i promised them . . . i would never copy the foolish example of other men, but that even in paris, on fine spring days, instead of pay- ing calls and listening to silly talk, i would set off for the country to see the first hawthorn-trees in bloom. [sw, pp. – ] so declares the narrator, whom for our purposes we may call marcel, and naturally he breaks this promise to the hawthorns quite soon, and thou- sands of pages later he is still absorbed with paying calls in paris and lis- tening to silly talk. that isn’t the end of the story, of course, and in his own way and in his own sweet time he remains faithful to his hawthorns, in the writing and remembering itself and their constant return to combray. encounters and declarations like this one to the hawthorns are the begin- nings of his vocation as a writer. in this passage and others in proust, we have a representative expression of the experience of beauty, and indeed much of the rest of the long novel is about his efforts and failures to keep faith with his early formative experiences of the beautiful. but to say even this much is already to risk losing critical perspective and speak from rather than about the consciousness of young marcel; for, really, what sense could there possibly be in “keeping faith” with anything like a bunch of hawthorn trees in bloom, however beautiful, as if one could have obli- gations of some sort with respect to them? well, for that matter, how is it that he takes himself to be addressing the hawthorns in the first place, bidding farewell, making to them a declaration of love, promising them to come see them again? for all the appearance of excessiveness in this passage (the mode of excess being proust’s own), it stands as a representative expression of the . to underscore that proust is indeed describing an aesthetic encounter here, i refer to his introduction to this scene eight pages earlier, where the language is unmistakable: and then i returned to the hawthorns, and stood before them as one stands before those masterpieces of painting which, one imagines, one will be better able to “take in” when one has looked away for a moment at something else; but in vain did i make a screen with my hands, the better to concentrate upon the flowers, the feeling they aroused in me remained obscure and vague, struggling and failing to free itself, to float across and become one with the flowers. they themselves offered me no enlightenment, and i could not call upon any other flowers to satisfy this mysterious longing. and then, inspiring me with that rapture which we feel on seeing a work by our favorite painter quite different from any of those that we already know, or, better still, when we are shown a painting of which we have hitherto seen no more than a pencilled sketch, or when a piece of music which we have heard only on the piano appears to us later clothed in all the colours of the orchestra, my grandfather called me to him, and, pointing to the tansonville hedge, said to me: “you’re fond of haw- thorns; just look at this pink one—isn’t it lovely?” [sw, p. ] critical inquiry / winter experience of beauty, even in its indulgence in language and attitudes nor- mally reserved for our relations with other persons. we often speak of the beautiful in terms of something appealing to us or demanding of our attention, and the pleasure we may experience in something beautiful raises the issue of its calling for that pleasure or that attention, in a way that does not apply to other things that may arrest our attention or gratify our senses. even the highly strung, overemotional marcel does not talk this way about the pleasures of eating or drinking, however discriminating his palate and however fine-grained his attention to experience. the things we consume, however intense their pleasures may be, raise no questions of something that might be betrayed or kept faith with, a claim or a call that might be answered or ignored. if there really is a difference between what kant calls the pleasure in the beautiful and the pleasure in the agreeable, this is not a difference in the degrees of pleasure taken, for the pleasure in the beautiful itself can be something faint or flickering, while the experi- ence of the merely agreeable can itself be overpowering. rather than a difference in the quality or intensity of pleasure, the distinction kant has in mind is a difference in attitude we take toward something we consider beautiful and consequently a difference in the type of judgment one is prepared to make on behalf of the thing we find beautiful— or so i shall argue. more specifically, i hope to show that kant’s emphasis on the de- mand for universal agreement to distinguish the judgment of the beautiful from the judgment of the agreeable is not in fact primary but is derived from a prior sense of necessity or demand that characterizes the experience of the beautiful itself. in short, universal agreement doesn’t always matter (aesthetics and ethics are not one), but the sense of the beautiful making a claim upon us does, and this much is derivable from kant’s initial distinc- tion between the beautiful and the agreeable. the agreeableness of canary wine and the beauty of a landscape or a work of art are both given expression in what kant calls a judgment of taste. both types of judgment of taste are based on a feeling of pleasure (or displeasure) and hence are subjective in the sense of denoting nothing in the object itself, not simply because the judgment is based on sensation, but more specifically because the particular sensation of pleasure is simply of the wrong sort to be a possible property of the object itself. neither type of judgment is based on concepts or reasoned to as the conclusion of some inference or argument but instead depends on one’s own direct experience of the thing in question. as a consequence, neither kind of judgment of taste can be made on the authority of someone else’s report or grounded in another person’s judgment or testimony. richard moran / beauty the fact that others have liked something can never serve him as a basis for an aesthetic judgment. if others make a judgment that is un- favorable to us, this may rightly make us wonder about our own judg- ment, but it can never convince us that ours in incorrect. hence there is no empirical basis of proof that could compel anyone to make [some] judgment of taste. second, still less can a judgment about beauty be determined by an a priori proof, in accordance with determinate rules. . . . it seems that this is one of the main reasons why this aesthetic power of judging was given that very name: taste. for even if someone lists all the ingredients of a dish, pointing out that i have always found each of them agreeable, and goes on to praise this food—and rightly so—as wholesome, i shall be deaf to all these reasons: i shall try the dish on my tongue and palate, and thereby (and not by universal principles) make my judgment. [cj, § , pp. – ] this is one dimension of the judgment of taste that kant refers to under the title of autonomy. under this aspect the judgment of taste is indepen- dent of both the judgments of other people and the rational determination of concepts. it may be that “as a rule” i do like foods of a certain kind, a kind that is determined by the applicability of certain concepts, but i can be disappointed in my expectations here and fail to find pleasure where i usually do. and more importantly, kant argues, there is nothing in the normative aspect of a rule that obliges me to take pleasure in something i find not to my liking, even if i agree that it fits the description of the kind of thing that as a rule i do like. logical or conceptual inconsistency has no grip here; there is nothing that would oblige me to bring my tastes into line with what is suggested by the concept or description of the thing in ques- tion. the normative center of gravity lies in one’s own direct experience of the thing, what kant calls apprehensio, and it cannot be overruled either by the concepts that the thing falls under or by the testimony of others. in the “on the method of the deduction and judgments of taste,” kant sums up this feature of the judgment of taste in the following way: its universal validity is not to be established by gathering votes and asking other people what kind of sensation they are having; but it must rest, as it were, on an autonomy of the subject who is making a judgment about the feeling of pleasure . . . i.e., it must rest on his own taste; and yet it is also not to be derived from concepts. [cj, § , p. ] critical inquiry / winter moreover, whenever a subject offers a judgment as proof of his taste . . . we demand that he judge for himself: he should not have to grope about among other people’s judgments by means of experience, to gain instruction in advance from whether they like or dislike that ob- ject. . . . that is why a young poet cannot be brought to abandon his persuasion that his poem is beautiful, neither by the judgment of his audience nor by that of his friends. . . . taste lays claim merely to au- tonomy; but to make other people’s judgments the basis determining one’s own would be heteronomy. [cj, § , pp. – ; my emphasis] at first glance, there is undoubtedly something arresting in kant of all people using the term autonomy to describe a context of judgment that is independent of the determination of rules or principles. surely it is kant who has shown most forcefully that freedom cannot be understood as anything like the mere absence of all constraint or principle (empirical or normative), for that would abolish the distinction between acting and being acted upon. rather, the very idea of acting freely means acting for some reason, which means acting in conformity with a law or principle that one gives oneself, which is what autonomy means. for now, let’s just note this as a stress that the kantian idea of autonomy is subjected to early in the analysis of the judgment of taste. more immediately, i want to point out that this sense of the autonomy of the judgment of taste applies equally to the agreeable as to the beautiful. that is to say, neither one’s judgment about the canary wine nor one’s judgment about the beautiful song or beautiful scene are normatively determined by principles or conceptual requirements, but can only be grounded in one’s own apprehensio of the thing in question. this is important to bear in mind, for kant also speaks of freedom and autonomy in characterizing the specific difference between the judgment of the agreeable and the judgment of the beautiful. this latter sense of autonomy is related to a sense of obligation that applies only to the pleasure in the beautiful and not the agreeableness of the canary wine. the pleasure or displeasure taken in the canary wine may not be compelled by rational or conceptual requirements, but this pleasure surely is compelled by something else, namely, the force of inclination, desire, and need. our relation to the agreeable is determined by and in the service of our char- acter as needy human animals, whereas the pure judgment of taste, the experience of something as beautiful, is independent both of our more basic biological inclinations and of the rational interests to which they give . see in particular kant, “transition from the metaphysics of morals to the critique of pure practical reason,” groundwork of the metaphysics of morals, trans. mary gregor (cambridge, ), pp. – . richard moran / beauty rise. in this way, the pleasure in the agreeable is a pleasure that is essentially in bondage. as a form of valuation, it possesses no independent validity of its own, for it is in the service of other, previously given ends with respect to which we are passive. for kant, a liking or a taking pleasure in some- thing that is an expression of our freedom is only possible when its condi- tions are independent not only of conceptual determination but also of determination by any desire or interest we may happen to bring to the experience. his liking is not based on any inclination he has . . . rather, the judg- ing person feels completely free as regards the liking he accords the object. [cj, § , p. ] we may say that, of all these three kinds of liking, only the liking in- volved in the taste for the beautiful is disinterested and free, since we are not compelled to give our approval by any interest, whether of sense or of reason. so we might say that [the term] liking, in the three cases mentioned, refers to inclination, or to favor [gunst], or to re- spect. for favor is the only free liking. neither an object of inclina- tion, nor one that a law of reason enjoins on us as an object of desire, leaves us the freedom to make an object of pleasure for ourselves out of something or other. [cj, § , p. ] thus, both the judgment of the agreeable and the judgment of the beautiful are free and autonomous with respect to both conceptual requirements and the judgments of other people. but the pure aesthetic judgment, the judgment of something as beautiful is also free in an additional sense, in that it is disin- terested, that is, free from the compulsion or determination of desire, interest, or need. thus, the famous kantian insistence on the disinterestedness of the judgment of beauty as the primary feature distinguishing it from the judgment of the agreeable is an aspect of what he calls the freedom of the pure judgment of taste. the pleasure in the beautiful is autonomous in the sense of answering only to itself and its own conditions, and not to those of any antecedent desire or interest we may have. this aspect of the autonomy belonging to the judgment of the beautiful is the expression of a difference in the attitude we take toward the objects we find beautiful, as contrasted with the things we find agreeable, gratify- ing, or the contrary. the beautiful is something that indeed gives pleasure, but we do not relate to it as something that simply answers to our purposes, critical inquiry / winter something to be consumed, used up, and disposed of. this thought has sources more ancient than kant and a varied afterlife as well. simone weil, for instance, strikes a characteristic note of self-denial when she says, “the beautiful is a carnal attraction which keeps us at a distance and implies a renunciation. . . . we want to eat all the other objects of desire. the beau- tiful is that which we desire without wishing to eat it. we desire that it should be.” but what is renounced in the experience of the beautiful (as contrasted with the agreeable) is not desire or gratification themselves; rather it is the authority and force of one’s presently constituted desires and interests, which are instead to be given over to and guided by the confrontation with something outside them, independent of them. here preservation is contrasted with consumption, and we can see here the primal distinction kant is appealing to between what we take inside and incorporate and what we stand before and behold. we might also say: we stand back from the beautiful, as with an object of respect or as with some- thing displayed or held in regard, whereas the agreeable is something we pick up, consume, and forget about. g. w. f. hegel is explicitly responding to kant in his introductory lectures on aesthetics and stages the encounter of desiring consciousness with the world in terms of the same opposition between what is taken inside and thus destroyed, and what is encountered within the world and thus preserved. in so doing he pursues further the relation between what is autonomous in the judgment of beauty and what is autonomous in the beautiful itself: in this appetitive relation to the outer world, the man stands as a sen- suous particular over against the things as likewise particulars . . . and preserves himself in them, inasmuch as he uses them, consumes them, and puts in act his self-satisfaction by sacrificing them to it. . . . just as little is it possible for desire to let the object subsist in its free- dom. for its impulse urges it just precisely to destroy this indepen- dence and freedom of external things, and to show that they are only there to be destroyed and consumed. but, at the same time, the sub- ject himself, as entangled in the particular limited and valueless inter- ests of his desires, is neither free in himself, for he does not determine himself out of the essential universality and rationality of his will, nor free in relation to the outer world, for his desire remains essentially determined by things and related to them. this relation of desire is not that in which man stands to the work of art. he allows it to sub- . simone weil, “beauty,” the simone weil reader, ed. george a. panichas (wakefield, r.i., ), p. . richard moran / beauty sist as an object, free and independent, and enters into relation with it apart from desire. what the criterion of disinterestedness means in kant is that the beautiful object is something that is liked for its own sake and not just insofar as it answers to our antecedent needs, desires, and interests. the immediately striking thing in hegel’s language is that he describes the situation as though the idea of liking an object “for its own sake” meant not simply liking noninstrumentally (which in one sense would apply to the relation to the agreeable as much as to the beautiful) but also as though the beau- tiful thing had an independent life of its own to which we had to adapt ourselves. for here and elsewhere he writes not only of the freedom in the conditions of the judgment of the beautiful (freedom from determination by desire and interest) but also of the freedom of the beautiful object itself—something in it, therefore, that we may respect or fail to respect. and yet, for all the extravagance of his language here, hegel is giving ex- pression to an idea that recurs in the history of aesthetics, the sense that what is regarded as beautiful is not experienced as a passive thing or as something that merely produces an effect in us but rather as inviting or requiring something from us, a response that may be owed to it. and in fact in this hegel is responding to a central feature of kant’s view of what is distinctive about the beautiful that has not yet entered our account here, which is the necessity that applies to the pleasure in the beautiful as con- trasted with that of the agreeable. the fourth moment of the analytic of the beautiful, on the modality of the pure judgment of taste, is summed up by kant in saying, “beauty is what without a concept is cognized [erkannt] as the object of a necessary liking” (cj, § , p. ). without yet inquiring how there could be such objects of necessary liking, and necessary for whom, we can see that the freedom or autonomy of the pleasure in the beautiful (its independence from desire or interest) must somehow be the ground of a necessity in the response to the beautiful, for neither this au- . g. w. f. hegel, introductory lectures on aesthetics, trans. bernard bosanquet, ed. michael inwood (london, ), p. . . or more properly, the work of art, for here hegel departs significantly from kant in giving primacy to artistic beauty over natural beauty. . here is ludwig wittgenstein, complaining about the language of producing effects, in connection with aesthetic matters, with the implication that the work of art is an instrumental means to an antecedent end or need: “there is a tendency to talk about ‘the effect of a work of art’—feelings, images, etc. then it is natural to ask: ‘why do you hear this minuet?’and there is a tendency to answer: ‘to get this and that effect.’ and doesn’t the minuet itself matter?—hearing this, would another have done as well?” (ludwig wittgenstein, lectures and conversations on aesthetics, psychology, and religious belief, ed. cyril barrett [maldon, mass., ], p. ). critical inquiry / winter tonomy nor any necessity at all applies to the pleasure taken in the merely agreeable. and it is this aspect of the pure judgment of taste that allows for the particular normativity in responding to the beautiful, something we may respect or fail to respect, a normativity that does not apply either to the pleasure of the agreeable or to ordinary empirical judgments such as those of color. the necessity attaching to the response to the beautiful that distin- guishes it from the response to the merely agreeable is reflected in the sense of requirement or demand that, for kant, is the fundamental difference between the judgment of the taste of reflection, which applies to what we find beautiful, and the taste of sense, which applies to what we find agreeable or gratifying. for, according to kant, the defining difference of the judgment of the beautiful is that, despite its independence of the re- quirements of concepts or principles, it nonetheless lays claim to universal validity. when speaking of something i find pleasant or agreeable, i am content to speak merely for myself and simply say that i like it, but if i am prepared to call something beautiful it is part of the very meaning of the judgment i mean to express that i present myself as speaking with what kant calls a universal voice. this universal voice has the character of a demand for or a requirement of the same liking or favoring from others. so fundamental is this difference that kant claims it would never occur to anyone to speak of beauty in the first place, rather than speak indifferently of any source of pleasure (without a concept), unless we intended this requirement of universal assent to our judgment. we must begin by fully convincing ourselves that in making a judg- ment of taste (about the beautiful) we require [ansinnen] everyone to like the object, yet without this liking’s being based on a concept (since then it would be the good), and that this claim to universal validity belongs so essentially to a judgment by which we declare something to be beautiful that it would not occur to anyone to use this term without thinking of universal validity; instead, everything we like without a concept would then be included with the agreeable. for as to the agreeable we allow everyone to be of a mind of his own, . cavell’s “aesthetic problems of modern philosophy” is still the best introduction to kant’s idea of speaking with a universal voice. as will be seen, i think that actual universality is the wrong direction for the communication of the judgment of beauty, but elsewhere in that same essay cavell makes the connection between aesthetic experience and communities smaller than that of universal humanity, between myself and others of my flesh, as he likes to say. the community that matters for the communicability and validity of a judgment of taste is less like universal humanity and more like a circle of intimates, fans, fellow enthusiasts. see also hamawaki, “kant on beauty and the normative force of feeling.” richard moran / beauty no one requiring [zumuten] others to agree with his judgment of taste. but in a judgment of taste about beauty we always require oth- ers to agree. [cj, § , p. ] to underscore that the person making such a judgment is making a nor- mative demand and not simply declaring his expectation that he is judging in accord with general humanity, kant favors a strongly imperatival lan- guage to describe the stance assumed by the judgment of beauty. in mak- ing such a judgment, we “requir[e] others to agree,” we demand (fordern) that they like it as we do, even: “we permit no one to hold a different opinion” (cj, § , p. ). but to speak in any of these ways raises the question of what could be the basis for such a requirement, and why agree- ment should matter in this way to the person who finds something beau- tiful, when for the most part it doesn’t matter that other people find the canary wine delightful as he does? what could be the source of such a demand? and given that judgments of the agreeable and of the beautiful are both judgments of taste, and hence involve a freedom that is not en- joyed by ordinary empirical judgments, kant’s insistence on an imperati- val aspect of the judgment of beauty creates problems for how the participants in such a dialogue understand what they are doing. for recall that a judgment of the beautiful is free in the dual sense of not being determined by a concept of the thing (as is a judgment of something as good, by contrast) and also not determined by any interest, desire, or need (as is a judgment of something as agreeable). thus, kant puts it, “only the liking involved in the taste for the beautiful is disinterested and free, since we are not compelled to give our approval by any interest, whether of sense or of reason” (cj, § , p. ). just as the person judging something to be beau- . on this circle of terms, see footnote here. guyer’s causal interpretation of the judgment of taste favors a rendering according to which what is claimed in the judgment is that all others will agree with it, subject to the proper conditions for the making of such judgments. as such his view downplays the explicitly normative language in kant in terms of the demand for agreement in favor of a factual reading in terms of the prediction of agreement. for support of the normative understanding of kant’s language here, hannah ginsborg writes: “the translation thus suggests, in a way that the original does not, that the claim to universal agreement is factual rather than normative: more specifically, that it is a prediction that others will agree with our judgment (at least under appropriate circumstances) rather than a strong normative claim that they ought to agree with it. this is in fact guyer’s view, but it is a controversial one” (hannah ginsborg, “critique of the power of judgment,” philosophical review [july ]: – ). henry e. allison also insists on the normative reading in his dialogue with guyer; see rebecca kukla, aesthetics and cognition in kant’s critical philosophy [cambridge, ], p. ), and henry e. allison, kant’s theory of taste: a reading of the critique of aesthetic judgment (cambridge, ), pp. , . . indeed, one might think, if they don’t share my good opinion of it, that just means more canary wine for me. critical inquiry / winter tiful recognizes that he is not compelled by reason, interest, or desire to acknowledge this thing as beautiful, he must recognize that if others are to so much as understand the kind of judgment he is making they must acknowledge themselves as similarly free with respect to it. this is de- manded by the concept itself. and yet in announcing the judgment of beauty he expresses himself in terms apparently denying the freedom of others to judge otherwise (“we permit no one to hold a different opinion”). here stands the aesthetic subject, confidently declaring something to be beautiful, and thereby requiring the agreement of everyone else, when by his own admission he can offer them neither reasons nor inducements to comply with this demand. and this is so not because of any inability of his, because he has not succeeded in finding the right kinds of reasons or inducements, but rather because of the very nature of the kind of claim he is trying to make. because it is a judgment of beauty (and not, for example, of goodness or pleasantness) he must both require universal agreement and at the same time divest himself of any reliance on the authority, rea- sons, principles, threats, or bribes that could bring his audience to comply with his requirement. and, indeed if he somehow managed to secure agreement in any of these ways, this could only mean that he has been misunderstood by his audience and perhaps that they simply lacked the concept of the beautiful altogether (and hence could not really know to what they agree). if his audience does not lack the concept of the beautiful, and therefore understands the condition of the autonomy of aesthetic judgment, they will not simply be disinclined to agree with the speaker, to accede to his demand for agreement, on the basis of his reasons or his authority. rather they will take themselves to be obliged to dismiss anyone who seeks to compel agreement in such a way, and this will be in virtue of their under- standing of the autonomy of the very kind of judgment being presented to them. this is not obstinacy on their part but an appreciation of the logic of the concept in question. and, indeed, kant presents just a scene for us: if someone reads me his poem, or takes me to a play that in the end i simply cannot find to my taste, then let him adduce batteaux or les- sing to prove that his poem is beautiful . . . moreover, let certain pas- sages that i happen to dislike conform quite well to rules of beauty (as laid down by these critics and universally recognized): i shall stop my ears, shall refuse to listen to reasons and arguments, and shall sooner assume that those rules of the critics are false, or at least do not apply in the present case, than allow my judgment to be determined by a richard moran / beauty priori bases of proof; for it is meant to be a judgment of taste, and not one of the understanding or of reason. [cj, § , p. ] hence, if this is how both parties to the discussion understand the auton- omy of the judgment of taste, this seems to present the spectacle of one person obliged by the nature of the kind of judgment he means to make to express it in terms requiring the agreement of all others, while at the same time knowing that his audience finds itself equally under the obligation, given the nature of the judgment in question, to stop their ears and refuse to listen. the speaker takes himself to be expressing a perfectly free liking, a liking that is in fact free in an additional sense to the freedom of an ordinary expression of pleasure in the agreeable. as kant says, we recog- nize the freedom of the taste of sense in the attitude of “allow[ing] every- one to be of a mind of his own, no one requiring [zumuten] others to agree with his judgment of taste. but in a judgment of taste about beauty we always require others to agree” (cj, § , p. ). what is strange in this is that, as we saw, the taste of reflection (judgment of beauty) enjoys the same freedom as does the ordinary taste of sense and in addition to that is also free in a way that is not enjoyed by the taste of sense, yet the result seems to be a restriction on the freedom that is granted to the ordinary judgment of the agreeable. what we seem to have here, then, is a perfectly free liking of my own that i nonetheless require of all others. what could ground such a requirement when it is itself the expression of a liking, a favoring, that is characterized as beyond (or before) all requirements? beauty is causally linked with pleasure and inspires love. . . . plato’s psychology is more accurate than kant’s: our earliest impression— and in that sense our prototype of beauty—is not a wildflower but a human face, one that is the focus of intense if ambivalent affect. or perhaps what all this suggests is that the liking, the favoring in ques- tion is not in fact experienced by the person as outside the bounds of all requirements or obligations after all. if we return to proust i think we can see the case for preserving a sense of necessity or requirement as a defining difference in the experience of the beautiful but one that obliges us to separate the sense of necessity or requirement in the encounter from the demand for universal agreement. in this way we can begin to see the aes- thetic subject as something other than an overbearing person who seeks to . mary mothersill, beauty restored (oxford ), pp. , . critical inquiry / winter impose on others what is for him a perfectly free liking, inventing a re- quirement out of something that is for himself free of all requirements. to begin with, not every sense of requirement is universal in form, and the obligations we feel to certain people, places, or other objects of love are often such that we can find it impossible even to explain them to another person, let alone to justify to them in such a way that they could come to find themselves under the same obligation themselves. nor would seeking such agreement always seem to the point or add any missing validation to the experience or sense of a claim upon oneself. the necessity experienced and lived out in one’s relation to a person or a vocation does not translate into a desire for or even the possibility of universal agreement. obligations and their necessities can come singly and individualize or even isolate the person who finds himself subject to one. we saw something of this in the young marcel’s tearful farewell to his hawthorns, his declaration of love to them, and his promise to keep faith with them. proust is hardly the first writer to be occupied with the relations between the demands of love and the appeal of beauty, but there may be no one who is more insistent on figuring the experience of the beautiful itself in explicitly intersubjective terms (being called to, summoned, or addressed), as if the sense of demand associated with the beautiful required nothing less. as with the experience of the beautiful itself, this can take more or less extreme forms and need not progress to the extremes of making promises or declarations of love. the experience of the beautiful is not always dramatic or even particularly intense, and the idea in question is about the category of judgment to which the beautiful belongs, not the degree of intensity in its experience. but proust wants something from the distinction between the beautiful and the agreeable that kant also wants, something that is not a difference in degree of intensity but a difference of logical category, which would account for a specific sense of requirement in the experience of what we regard as beautiful that does not apply to our other sources of gratification. the various sources of gratification exist for us in terms of answering to our needs and are valued according to how well they perform this service. but something we are prepared to call beautiful is not measured purely by its ability to satisfy our given desires but is rather something to which our . and as in harry g. frankfurt’s discussion of the volitional necessities of love, the thought is not that love itself is demanded or required but that loving something or someone creates necessities for the person, marking out the limits of what can coherently be willed, creating obligations of responsiveness and attention. see harry g. frankfurt, the reasons of love (princeton, n.j., ) and necessity, volition, and love (cambridge, ). i discuss the relations of love and necessity in richard moran, “the reasons of love by frankfurt,” review of the reasons of love by frankfurt, philosophy and phenomenological research (mar. ): – . richard moran / beauty pleasure or desires themselves may be answerable, to which they may need to conform themselves, or by which they may be instructed. this much, i would claim, follows from kant’s original distinction between the agree- able and the beautiful. and we can put the same point in more explicitly proustian terms by relating it to his great theme of disappointment. for it is when we are prepared to call something beautiful that there is now logical room not simply for disappointment in one’s experience, as there might be with respect to any hoped-for source of pleasure, but for disap- pointment in oneself rather than in the object, for the various possibilities of failure of responsiveness. with respect to the hawthorns, marcel makes a vow that he soon breaks but later makes good on. later in the story, with respect to the shifting views of three trees that he sees at evening from a moving coach, he takes this structure of normativity to what is even for proust remarkable extremes, incorporating several of the strands from beauty’s mythology that we have seen before. i looked at the three trees; i could see them plainly, but my mind felt that they were concealing something which it could not grasp, as when an object is placed out of our reach. did they conceal beneath their surface, like the trees, like the tufts of grass that i had seen beside the guermantes way, a meaning as ob- scure, as hard to grasp, as is a distant past, so that, whereas they were inviting me to prove a new thought, i imagined that i had to identify an old memory? or again, were they concealing no hidden thought, and was it simply visual fatigue that made me see them double in time as one sometimes sees double in space? i could not tell. . . . i chose rather to believe that they were phantoms of the past, dear compan- ions of my childhood, vanished friends who were invoking our com- mon memories. like ghosts they seemed to be appealing to me to take them with me, to bring them back to life. in their simple and passion- ate gesticulation i could discern the helpless anguish of a beloved per- son who has lost the power of speech, and feels that he will never be able to say to us what he wishes to say and we can never guess. pres- ently, at a cross-roads, the carriage left them. it was bearing me away from what alone i believed to be true, what would have made me truly happy; it was like my life. i watched the trees gradually recede, waving their despairing arms, seeming to say to me: “what you fail to learn from us today, you will never know. if you allow us to drop back into the hollow of this road from which we sought to raise ourselves up to you, a whole part of critical inquiry / winter yourself which we were bringing to you will fall for ever into thin air.” and indeed if, in the course of time, i did discover the kind of plea- sure and disquiet which i had felt once again, and if one evening—too late, but then for all time—i fastened myself to it, of those trees them- selves i was never to know what they had been trying to give me nor where else i had seen them. and when, the road having forked and the carriage with it, i turned my back on them and ceased to see them, while mme de villeparisis asked me what i was dreaming about, i was as wretched as if i had just lost a dear friend, had died myself, had broken faith with the dead or repudiated a god. even by proust’s own exalted standards, the language here is extreme in its depiction of the experience of being captivated, and its very extremity helps to make visible a more general idea of norms of responsiveness that have some claim to define the idea of the beautiful as such. and, as men- tioned earlier, with any distinct form of normativity there will be distinct possibilities for violation of the norm or failure to conform to its demands. the young marcel breaks his promise to the hawthorns early on but makes good on it later. in this passage the forms of normative failure are figured in terms of the threat of betrayal, fearing that one’s own response will turn out to have been one of faithlessness or heedlessness, the failure to answer some question posed to oneself alone, and thus the threat of loss of self or of the possibility of one’s genuine life. there is a demand here, surely, but it is not a demand for universal agreement. rather, it is something whose consummation would require him to be alone. and in the reference to “the helpless anguish of a beloved person who has lost the power of speech” there is even a proleptic allusion to the death of the most beloved person in the book, marcel’s grandmother, who does indeed lose the power of speech, and the delayed response to whose death, several volumes later, is the occasion of one of the great cataclysms of his life, an eruption of the past and the self-reproach for his failures of responsiveness in the present both when she was alive and for a full year after her death. while i have been emphasizing the strain in kant’s account, stemming from his insistence on the universal imperatival character of the judgment of beauty, he does himself appeal to the necessities of love to characterize the specific modality that distinguishes the pleasure of the beautiful from the pleasure of the agreeable. his formulation, “the beautiful prepares us for loving something, even nature, without interest; the sublime, for es- teeming it even against our interest (of sense)” (cj, § , p. ), expresses . proust, within a budding grove, trans. moncrieff and kilmartin (new york, ), pp. , ; hereafter abbreviated bg. richard moran / beauty the competing side of his thinking that aligns him with a tradition of thinking about beauty that goes back at least as far as sappho. it provides one way to make out the necessity kant insists on in the judgment of the beautiful without the need to assimilate it to a demand for universal agree- ment or to subsume the specific normativity of the beautiful to that of morality. there are wilder and more measured experiences of the beauti- ful, after all, and the form of normative requirement in a given case need not take the dramatic forms described by proust. we only need to hold onto the sense that it belongs to the beautiful but not to the agreeable and that there can be types of responses or ways of treating the thing that are called for, merited by, or owed to it and hence that there are possibilities for characteristic failures of response or repudiations of the appeal that have no place in our relation to the agreeable things we consume. when plato or mary mothersill claim an internal relation between beauty and love, this needn’t be understood as either sentimentalizing or inflating the experience of the beautiful but rather as a recognition of the conceptual difference between something’s being a value because it answers to my needs and recognizing something whose claim on me is independent of my needs, a value that my needs and desires are themselves answerable to. part of what it means to say that “beauty inspires love” must be that the pleasure it causes is experienced as the recognition of a value to which my present interests and desires are themselves answerable or by which they are to be measured and hence a value that can create obligations (of attention, pres- ervation, understanding, communicating, and so on). if a certain kind of pleasure can be said to inspire love, then that means that it now provides us with something it is possible to be true to or not, to betray or not, to keep faith with or not. both kant and proust want to identify something unconditional in the appeal of beauty. and we might see one aspect of the unconditional in the appeal of beauty that is shared by both kant and proust as emerging fairly directly from the distinction between the pleasure of the beautiful and the . “by beauty [as distinguished from the sublime], i mean that quality or those qualities in bodies by which they cause love, or some passion similar to it. . . . i likewise distinguish love, by which i mean that satisfaction which arises to the mind upon contemplating anything beautiful . . . from desire . . . which is an energy of the mind, that hurries us on to the possession of certain objects” (edmund burke, a philosophical enquiry into the origin of our ideas of the sublime and beautiful [oxford, ], p. ). alexander nehamas’s only a promise of happiness came out as i was completing this paper, and, among its other virtues, his account both explores the conceptual connections between beauty and love and appeals to this connection by way of rejecting the claim for universal agreement. see alexander nehamas, “beauty, community, universality,” only a promise of happiness: the place of beauty in a world of art (princeton, n.j., ), pp. – . critical inquiry / winter pleasure in the agreeable: the idea of a demand on the subject that is inde- pendent of one’s current likes and dislikes. this is clear enough in kant and is part of his definition of the autonomy of the beautiful. for proust, we can begin by noting that the experiences he relates in passages like these are not descriptions of the gratification of some antecedently existing ap- petite for either hawthorns or the shifting appearances of trees as seen from a moving coach. rather, the value they represent for him does not depend on their answering to his preexisting desires. kant may sometimes write as if recognizing such a value were incompatible with the felt desire for the bearers of such values or required the suppression of such desire, but surely that is a mistake. the point is that the value in question and its claim upon me is recognized as not conditional on my having such desires. and, for both writers, the idea of something whose status as a value does not depend on my current desires or interests brings to the experience of that value a sense of my being measured by it (rather than my estimating it according to my own needs) and a normative direction of fit from oneself to the beautiful object rather than the reverse. the standard english trans- lation of the german angenehm as “agreeable” is apt for expressing this contrast. for when there is failure of fit between my appetite and the food and drink i consume, we speak of it as “not agreeing with me,” and with that the meal is dismissed, whereas when i am prepared to think of some- thing as beautiful the question of my being in agreement or not with it is more centrally the question the aesthetic subject is faced with. here the possibilities of failure of agreement are not limited to bringing the object into line with one’s desire but can expand from disappointment in one’s own responsiveness, to the sense of lost receptivity thematized for example in the odes to loss and dejection of william wordsworth and samuel taylor coleridge and on to proust’s deliberately hyperbolic description of himself as feeling “as wretched as though i had just lost a friend, had died myself, had broken faith with the dead or repudiated a god.” (where kant joins proust is in finding room in the idea of beauty for the possibility of being chastened or humbled by the experience, finding one’s own response to it to be inadequate.) the sense of a demand or requirement as characterizing the experience of the beautiful brings a dimension of normativity to the judgment of beauty that distinguishes it from both the ordinary empirical judgment of something as, for example, red and the more explicitly evaluative judg- ment of something as pleasant or agreeable. i have been arguing that this represents one of kant’s best insights about the beautiful, but i have also been suggesting that his particular ways of elucidating this dimension of normativity are unsuccessful, even within his own terms. in this paper i richard moran / beauty won’t attempt to address with any adequacy the terms of kant’s positive account, but i do want to say something about two main lines of this account and what i see as unsatisfying about them. to begin with, it might be argued that we create an unnecessary air of mystery by speaking of something normative or demanding as issuing from the beautiful itself when it should be clear that the only genuine demand in question here is the one kant explicitly insists on, namely, a demand coming from another person, that is, the demand for agreement with his judgment. part of the problem with any response in these terms is that it doesn’t help us under- stand what the source of this demand itself could be and how it could be, for kant, the primary feature that distinguishes the judgment of beauty from the judgment of the agreeable. if we acknowledge that we do not demand such agreement with regard to what we find agreeable, even though as kant also acknowledges we may have better reason to expect actual agreement there than in the case of the beautiful, then the particular demand for agreement contained in the judgment of the beautiful cannot be explained by reference to the normativity of either ordinary empirical judgments or declarations about genuine sources of pleasure. it must have some different basis, and the person making such a demand for agreement cannot understand himself to be backing this demand with the claim that he has, after all, identified a genuine source of pleasure here, one that you are obliged to share with him in enjoying. to refer the sense of require- ment back to the person making a demand for agreement simply pushes back the question of why there should be any importance to agreement here that there is not with respect to our other pleasures and what it could be about this experience and the person’s relation to it that puts him in a position from which he could make such a demand, a demand that an- other person would have any reason to respect. if we begin simply with one’s experience of some kind of pleasure, something that is a perfectly free liking, then it is hard to see how adding to it a demand for universal . but surely there is something strange here. in the case of the taste of sense, not only does experience show that its judgment (of a pleasure or displeasure we take in something or other) does not hold universally, but people, of their own accord, are modest enough not even to require others to agree (even though there actually is, at times, very widespread agreement in these judgments too). now, experience teaches us that the taste of reflection, with its claim that its judgment (about the beautiful) is universally valid for everyone, is also rejected often enough. what is strange is that the taste of reflection should nonetheless find itself able (as it actually does) to conceive of judgments that can demand such agreement, and that it does in fact require this agreement from everyone for each it its judgments. [cj, § , p. ] critical inquiry / winter agreement can by itself contribute any special normativity to the situation or bring us closer to the concept of the beautiful. so far it remains simply a pleasure of mine to which i have added the otherwise unmotivated re- quirement that others agree with me. in response to such difficulties, some commentators on kant wish to show that the imperatival character of the judgment of beauty is in fact dispensable in kant and does not in fact mark anything distinct from the normativity of ordinary empirical judgments. my own view is that kant is right in this, as well as in agreement with proust, in finding a sense of necessity or demand with respect to the beautiful that is not found with respect to either the agreeable or ordinary empirical judgments. however, he mislocates it in the demand for universal agreement, in part because necessity and universality are so deeply conjoined for him. (the passages from proust and the relations between the experience of beauty and the necessities of love are meant to remind us that not all necessities take that universal form.) kant is clear that something normative needs to under- write the demand for universal agreement, and he is also clear that no sense of requirement can be derived simply from the goodness of pleasure itself. that is, if i demand universal agreement in the pleasure i take in some- thing, my reason cannot be that otherwise you would be missing out on a true source of pleasure, which is a genuine good. however heartfelt, any recommendation of that sort may legitimately be dismissed, either because you doubt that we do take pleasure in the same things or because you are perfectly satisfied with the sources of pleasure with which you are already familiar. you may not doubt me about my own pleasure or that i have identified a possible source of pleasure for you, yet you may still find that all this has no claim upon you. and, perhaps more importantly from kant’s own perspective, nothing of that character could explicate the sense of requirement in the judgment of beauty since, as he puts it, “an obliga- tion to enjoy oneself is a manifest absurdity” (cj, § , p. n. ). it is, i think, because his original distinction between the agreeable and the beautiful is characterized in terms of a sense of obligation or require- ment attaching to the one but not the other (something i’m claiming is shared by proust) and because he recognizes the need for an account of its . compare to mothersill: “that idea is strongly counter-intuitive. nothing would be lost if judgments were treated as assertions (or declarative sentences), as candidates for truth,” and “in short, the idea of an aesthetic imperative seems a liability to kant’s theory from every point of view” (mothersill, beauty restored, pp. , ). note that she is disagreeing with kant here and not with the “normative” or imperatival interpretation of kant. throughout this paper i am trying to tease out what is correct in kant’s appeal to a normative element in the judgment of beauty that is additional to the norms for correct empirical judgment quite generally (for example, color judgments). such judgments can still for all that be candidates for truth. richard moran / beauty basis that throughout the critique of judgment he makes various attempts to locate the source of this normativity somewhere or other, primarily and predictably in the demands of morality. so, for instance, he argues that we require that all others take disinterested pleasure in the beauty of the nat- ural world because the capacity to do so makes us more fit for the moral life (see cj, § , pp. – ). or alternatively it may be that a capacity for disinterested pleasure is at least a reliable sign of moral sensitivity and hence to be welcomed and approved of (even, that is, if we are unsure of its independent contribution to good moral character) (see cj, § , pp. – ). or, in a different register, kant will suggest that the possibility of our finding beauty in the world encourages us in our faith that pure practical reason can actually be effective in the empirical world because the experi- ence of beauty intimates that we are in some sense, after all, made for each other, fitted to each other’s requirements (see cj, §§ , , pp. – , – ). and taking these and other considerations together may bring us to the idea that beauty is in fact a symbol of morality (see cj, § , pp. – ). i will make no attempt to do justice to these large questions, and although i am skeptical about this entire line of thought i will not defend that skepticism here beyond mentioning my sense that the very diversity and inconclusiveness of the relations kant suggests between beauty and morality indicates to me that they have a tentative or at least unresolved status in his overall argument. however, even if no objection is made to any of the claims just mentioned, either individually or collectively, i think it can be argued that even their truth would not provide us with an answer to the question that kant originally posed for us. for that was a question about the normative force of a claim in response to a particular experience of beauty, a normative dimension that is distinct from the normativity of an ordinary empirical judgment or the recom- mendation to avail oneself of a source of pleasure. and the sense of re- quirement associated with this particular experience of something beautiful cannot be explicated by reference to a quite general obligation to cultivate one’s capacity for disinterested pleasures (so as to provide “a transition from sense enjoyment to moral feeling” [cj, § , p. ]). this was our original problem, the special normative dimension of the singular judgment of beauty and how it could underwrite the demand for universal agreement, even though kant is equally insistent that the pleasure in ques- tion is a perfectly “free liking” and that any such agreement could not be required by reference to concepts or principles. we would not be closer to understanding this even if we were convinced by kant’s claim of the “in- tellectual interest in the beautiful” that “to take a direct interest in the beauty of nature (not merely to have the taste needed to judge it) is always critical inquiry / winter a mark of a good soul; and that, if this interest is habitual, if it readily associates itself with the contemplation of nature, this [fact] indicates a mental attunement favorable to moral feeling” (cj, § , pp. – ). and this is because, for kant, any judgment of taste, whether of the beautiful or the agreeable, is a singular judgment, and hence whatever normativity characterizes it and distinguishes it from the agreeable cannot be under- stood by reference to the moral recommendation to cultivate a sensibility for pleasure and judgments of that general type. i would also argue that the appeal to morality suggests the wrong role for agreement in the experience of beauty and the wrong importance for it. there are obvious reasons concerned with the nature of morality why the very demandingness of the moral should be understood in terms of the conditions for securing agreement between people. moral and political conflicts are a fact of life and can exact a terrible price on the contenders involved because they have to live together and find ways to respect and make comprehensible the demands they make on each other. while it is true that our different experiences of beauty can be painful or alienating in certain circumstances, they do not demand resolution and agreed-upon terms of fair agreement before civil life can resume. and we differ in our experiences of the agreeable as well, though as kant notes, in these contexts we are “modest enough not to require others to agree” (cj, § , p. ), even when we are aware that, in fact, actual agreement about the agreeable is often more widespread than agreement about the beautiful. it seems that it could only be our different attitude toward the beautiful itself that could account for why we should ever treat our experiences of the beautiful any differently, taking that additional step when we know it is likely to be repudiated. but that, i’ve been suggesting, requires detaching the demand for agreement from the sense of necessity or requirement in the experience itself. if proust’s narrator can understand himself to be making a vow of some sort to his hawthorns, what he is doing is meant to place himself under an obligation, something like the vow to remain responsive to this beauty . “it is a fact that any judgment of taste is always a singular judgment about the object” (cj, § , p. ). “that is also why all judgments of taste are singular judgments, because they do not connect their predicate, the liking, with a concept but with a singular empirical presentation that is given” (cj, § , p. ). . compare john rawls: “a second contrast between the right and the good is that it is, in general, a good thing that individuals’ conceptions of their good should differ in significant ways, whereas this is not so for conceptions of right. . . . moreover, there is no urgency to reach a publicly accepted judgment as to what is the good of particular individuals. the reasons that make such an agreement necessary in questions of justice do not obtain for judgments of value” (john rawls, a theory of justice [cambridge, mass., ], p. ). richard moran / beauty because it defines him. this is a kind of imperative addressed to himself, but it is something different from a demand for universal agreement. in making a vow to the hawthorns and promising that he will be true to them in spite of the pleasures and distractions of “paying calls and listening to silly talk,” he is both affirming the superior value of the hawthorns and attempting to bind himself to that value. he feels the binding is necessary not only because of the temptations of gossiping in the city but because he feels that the appeal of the hawthorns, however intense, is nonetheless something fragile, and, that were he to lose his responsiveness to this ap- peal, it would count as a loss of the self he presently is and cares about. by contrast, the experience of the agreeable does not carry with it a similar threat. with respect to something agreeable, to lose one’s desire for it is typically to find something else more agreeable or equally so and move on. there need be no experience of the loss of some part of oneself and hence nothing to mourn or regret in this change of tastes. marcel does not mea- sure himself against his responsiveness to the agreeable, and he doesn’t make vows to their objects because the possibility of ceasing to find them a source of pleasure is not something he needs to preserve himself against, because that possibility is not experienced as any kind of failure on his part. within the general economy of the agreeable, if i am tempted by some- thing else that distracts me from my original desire, i have no reason, apart from prudential or moral considerations extrinsic to the desire itself, not to follow what happens to please me more and abandon what no longer pleases me as much. binding oneself against loss or lapse is not called for, and therefore there is no sense to a vow of any kind. with respect to the beautiful, however, he claims a value in continuing to cherish this object, continuing to be responsive to its appeal, which is over and above the value of the pleasure it presently gives him and may survive it. in regarding the beautiful or an object of love, there is room for the idea of failure in the possibility of the abandonment or replacement of one’s desire, the pros- pect of which is experienced as a threat to the self. it is this threat that marcel shrinks from when swann suggests to him that if he moved away from france and formed other attachments he would not be tormented by gilberte or other unattainable objects of his desire. but the prospect of other attachments, along with the forgetting of his current ones and thus the relief from the suffering they are now causing him are not seen by him as any form of compensation for or solution to his current sufferings but only as adding to them. swann is here representing the perspective of an enlightened egoistic hedonism, according to which the elimination of an unfulfilled longing can count in the same way as a satisfied desire in the economy of pleasure. marcel recognizes a certain hedonic rationality in critical inquiry / winter this perspective, and he feels the claim of what he calls his “better judg- ment” here, and yet he recoils from swann’s suggestion as entailing the obliteration of the self whose future well-being could matter to him in the first place. the abandonment recommended by swann and the perspective of the rational management of the agreeable is regarded by him with dread: this dread, far from being dissipated, is intensified, if to the pain of such a privation we feel that there will be added what seems to us now in anticipation more painful still: not to feel it as a pain at all—to re- main indifferent; for then our old self would have changed . . . it would be in a real sense the death of the self, a death followed, it is true, by resurrection, but in a different self, to the love of which the elements of the existing self that are condemned to die cannot bring themselves to aspire. [bg, p. ] both kant and proust could say that marcel knows his experience of beauty presents him with something in the form of a normative demand that is not contained in the experience of the agreeable because it is the beautiful and not anything he finds merely agreeable (and this is the whole force of the “mere” in this context) that presents him with the possibility of something he might fail or stray from. and for both of them in response to the beautiful, acknowledging the possibility of characteristic forms of fail- ure of response means acknowledging oneself as subject to something with the force of a requirement. many writers have wanted to describe the encounter with beauty in terms of the claim of something outside the world of egoistic desire and in this way provide a place for the ideas of objectivity, impersonality, and universality as applied to beauty. this is only partly kant’s way. he shares the sense of the concept of beauty being reserved for something outside of and imposing itself upon egoistic desire . and yet my . . . better judgment whispered: “what difference can that make, since you won’t be distressed by it? when m. swann tells you that you won’t come back he means by that that you won’t want to come back, and if you don’t want to that is because you’ll be happier out there.” for my judgment was aware that habit . . . undertakes as well to make dear to us the companions whom at first we disliked, to give another ap- pearance to their faces, to make the sound of their voices attractive, to modify the incli- nations of their hearts. it is true that these new friendships for places and people are based upon forgetfulness of the old; but my reason precisely thought that i could envis- age without dread the prospect of a life in which i should be for ever separated from people all memory of whom i should lose, and it was by way of consolation that my mind was offering to my heart a promise of oblivion which succeeded only in sharpen- ing the edge of its despair. [bg, p. ] richard moran / beauty and hence as being impersonal or at any rate transpersonal in its meaning. and while he does, of course, seek to join this to a claim to universality, he differs from other writers on beauty in seeking to maintain such univer- sality while, for principled reasons, denying that beauty is any kind of objective property of things (not even of the sort belonging to secondary qualities such as colors). this is indeed his central paradox. without claiming that proust solves this paradox, we can see that he draws our attention to a dimension of the aesthetic that fits better with the logical form of the kind of claim kant wants to make for beauty, while avoiding the internally problematic features of demands for universal agreement, even universal enjoyment that can’t be met on his own terms, whether because pleasure, like any other affect, cannot coherently be commanded, or because “an obligation to enjoy oneself is a manifest absurdity” (cj, § , p. n. ), or because the autonomy of the judgment of taste obliges anyone in possession of the concept of that kind of judgment to dismiss any such demand for “approval by any interest, whether of sense or of reason” (cj, § , p. ). proust will agree with kant that an invocation of necessity is needed to carve out the concept of the beautiful from the indifferent mass of the merely agreeable and consumable. but instead of the juridical, legislating context favored by kant here and elsewhere, proust is concerned instead with the necessity whose source is the thing itself in front of him, the one that has arrested his attention. . see ginsborg, “kant on the subjectivity of taste,” in kant’s aesthetics, ed. herman parret (berlin, ) for an especially helpful discussion of this paradox and kant’s principled reasons for denying that beauty can have the kind of objectivity of any ordinary property. i have profited from this paper in several ways. critical inquiry / winter stalnaker on sleeping beauty brian weatherson the sleeping beauty puzzle provides a nice illustration of the approach to self-lo- cating belief defended by robert stalnaker in our knowledge of the internal world (stalnaker, ), as well as a test of the utility of that method. the setup of the sleeping beauty puzzle is by now fairly familiar. on sunday sleeping beauty is told the rules of the game, and a (known to be) fair coin is flipped. on monday, sleeping beauty is woken, and then put back to sleep. if, and only if, the coin landed tails, she is woken again on tuesday after having her memory of the monday awakening erased. on wednesday she is woken again and the game ends. there are a few questions we can ask about beauty’s attitudes as the game progresses. we’d like to know what her credence that the coin landed heads should be (a) before she goes to sleep sunday; (b) when she wakes on monday; (c) when she wakes on tuesday; and (d) when she wakes on wednesday? standard treatments of the sleeping beauty puzzle ignore (d), run together (b) and (c) into one (somewhat ill-formed) question, and then divide theorists into ‘halfers’ or ‘thirders’ depending on how they answer it. following stalnaker, i’m going to focus on (b) here, though i’ll have a little to say about (c) and (d) as well. i’ll be following orthodoxy in taking to be the clear answer to (a), and in taking the correct answers to (b) and (c) to be independent of how the coin lands, though i’ll briefly question that assumption at the end. an answer to these four questions should respect two different kinds of con- straints. the answer for day n should make sense ‘statically’. it should be a sensible answer to the question of what beauty should do given what information she then has. and the answer should make sense ‘dynamically’. it should be a sensible answer to the question of how beauty should have updated her credences from some earlier day, given rational credences on the earlier day. as has been fairly clear since the discussion of the problem in elga ( ), sleep- ing beauty is puzzling because static and dynamic considerations appear to push in different directions. the static considerations apparently favour a answer to (b). when beauty wakes, there are three options available to her: it is monday and the coin landed heads; it is monday and the coin landed tails; it is tuesday and the coin landed tails. if we can argue that each of those are equally probable given her evidence, we get the answer . the dynamic considerations apparently favour a † penultimate draft only. please cite published version if possible. final version published in philo- sophical studies ( ): - . thanks to adam elga, elizabeth harman, ishani maitra, ted sider, robert stanlaker and seth yelcin for comments on an earlier, and mistake-riddled, draft. note that i’m not assuming that beauty’s memories are erased in other cases. this makes the par- ticular version of the case i’m discussing a little different to the version popularised in elga ( ). this shouldn’t make any difference to most analyses of the puzzle, but it helps to clarify some issues. stalnaker on sleeping beauty answer to (b). the right answer to (a) is . nothing happens on monday or tuesday that surprises beauty. and credences should only change if we are surprised. so the right answer to (b) is . since we must have harmony between dynamic and static considerations, one of these arguments must be misguided. (in fact, i think both are, to some degree.) these days there is a cottage industry of ‘thirders’ developing accounts of credal dy- namics that accord with the answer to (b). but all of these accounts are consid- erably more complex than the traditional, conditionalisation-based, dynamic theory that we all grew up with. three of the many attractions of robert stalnaker’s new account of self-locating knowledge are (i) that it offers a way to answer all four of our questions about sleep- ing beauty, (ii) that it does so while remaining both statically and dynamically plau- sible, and (iii) that the dynamic theory involved is, in large part, traditional condi- tionalisation. i spend most of this note setting out stalnaker’s account, and setting out his derivation of a answer to (b). i conclude with some reasons for preferring a slightly different solution of the sleeping beauty puzzle within the broad framework stalnaker suggests. stalnaker on self-location the picture of self-locating belief that we get from lewis’s “attitudes de dicto and de se” (lewis, ) has been widely adopted in recent years. on lewis’s picture, the content of an attitude is a set of centered worlds. for current purposes we’ll take to centered worlds to be ⟨world, agent, time⟩ triples. to believe that s, where s is a set of centered worlds, is to believe that the triple ⟨your world, you, now⟩ ∈ s. the motivation for this picture comes from reflection on how to represent loc- ational uncertainty. if you’re sure where in new york city you are, you can pick out a point on a map and say “i’m there”. if you’re not sure exactly where you are, but you have some information, you can pick out a region on the map and say “i’m somewhere in that region”. if you’re not sure who you are, but you know where everyone is, you can do the same kind of thing. and it’s plausible that this is a (somewhat) realistic situation. as one modern-day lewisian, andy egan, puts it ‘i can believe that my pants are on fire without believing that egan’s pants are on fire, and i can hope that someone turns a fire extinguisher on me right now without hop- ing that someone turns a fire extinguisher on egan at : pm.” (egan, , ) there is an important puzzle here that needs to be addressed, and can’t obviously be addressed in the framework lewis accepted before , where the content of a propositional attitude is a set of lewisian concreta. if possible worlds are lewisian concreta, then lewisians like egan are correct to respond to puzzles about location by saying, “sometimes (as when we want to know who or where we are) the world is not enough”. (egan, , ) but this response is too self-centered. not all locational thoughts are self-loc- ational thoughts. i can be just as uncertain about where that is as about where this see, for instance, titlebaum ( ) and the references therein. including by me. see egan et al. ( ) stalnaker on sleeping beauty is, or as uncertain about who you are as about who i am. imagine i’m watching egan’s unfortunate adventures with his infernal trousers on a delayed video tape. i can believe his pants are on fire without believing egan’s pants are on fire, and hope that someone turns a fire extinguisher on him then without hoping some turns a fire extinguisher on egan at : pm. or, at least, that way of putting things sounds just as good as egan’s original description of the case. for a different example, imagine i wake at night and come to believe it is mid- night. as lewis would represent it, i believe ⟨w, me, now⟩ ∈ {⟨w, s, t⟩ : t = midnight}. when i wake, i think back to that belief, and judge that i may have been mistaken. how should we represent this? not that i now believe ⟨w, me, now⟩ /∈ {⟨w, s, t⟩ : t = midnight}. that’s obviously true - i know the sun is up. we want to represent something more contentious. the best, i think, the lewisian can do is to pick out some description d of my earlier belief and say what i believe is ⟨w, me, now⟩ /∈ {⟨w, s, t⟩ : (ιx : dx)x happens at midnight}. that is, i believe the belief that satisfies d doesn’t happen at midnight. is that good enough? well, we might imagine the debate continuing with the anti- lewisian proposing cases where d will not be unique (because of forgotten similar beliefs) or will not be satisfied (because of a misrecollection of the circumstances of the belief ), and so this approach will fail. and we might imagine the lewisian responding by complicating d, or by denying that in these cases we really do have beliefs about our earlier beliefs. in other words, we can imagine the familiar debates about descriptivism about names being replayed as debates about descriptivism about prior beliefs. as enjoyable as that may be, it’s interesting to consider a different approach. there’s a more philosophical reason to worry about lewis’s model. if we model uncertainty as a class of relationships to possible worlds, it looks like there’s a lot of actual uncertainty we won’t be able to model. indeed, there are three kinds of uncertainty that we can’t model in this framework. first, we can’t model uncertainty about logic and mathematics. second, if we accept the necessity of identity, we can’t model uncertainty about identity claims. whatever it is to be uncertain about whether a is b, it won’t be a distinctive relation to the set of worlds in which a is b, since that’s all the worlds. third, we can’t model uncertainty about claims about self-identity, like i’m that guy. lewis’s framework is an improvement on the sets of possible worlds approach because it helps with this third class of cases. but it doesn’t help with the first or, more importantly, with the second. we might think that a solution to puzzles about self-identity should generalise to solve puzzles about identity more broadly. lewis’s model doesn’t. one of stalnaker’s key insights is that we should, and can, have a model that addresses both kinds of puzzles about identity. on stalnaker’s model, a belief is just a distinction between worlds. the content of a belief is a set of worlds, not a set of centered worlds. but worlds have more structure than we thought they had. the formal model is a bit more subtle than what i’ll sketch here, but i think i’ll include enough detail to cover the sleeping beauty case. in each world, each center, in lewis’s sense, has a haecceity. a world is the cartesian product of a lewisian world, i.e. a world without haecceities, and stalnaker on sleeping beauty a function from each contextually salient haecceity to a location. if we see a kiss, and wonder who she is, who he is, and when they are kissing, then we can think of the worlds as quadruples consisting of a haecceity-free world (perhaps a lewisian concreta), a woman, a man and a time. so we can represent three kinds of locational doubts, not just self-locational doubt. when an agent at center c believes something self-locating, e.g. that it is mon- day, the content of their belief is that c’s haecceity is on a monday. if they don’t know what day it is, there’s a sense in which they don’t know what they believe, since they don’t know whether what they are believing is that c’s center is on monday, or that some other center’s haecceity is on monday. but their belief, the belief they would express on monday by saying “it is monday”, has two nice features. first, it is nei- ther trivial, like the belief that monday is monday, nor changing in value over time, since c’s center is always on monday. second, it is the kind of belief that people on days other than monday can share, or dispute. and this belief can be shared by others who have the capacity to think de re about c, even if they can’t uniquely describe it. it’s this last fact that lets stalnaker handle the cases that proved problem- atic for lewis and the neo-lewisians. for instance, it lets stalnaker model shared uncertainty about identity claims. with all that in place, it’s time to return to sleeping beauty. let’s consider two propositions. the first, h, is that the coin landed heads. the second, m, is what beauty can express when she wakes on monday by saying “it is monday”. that is, it is a singular proposition about a wakening experience that beauty can now have singular thoughts about (since she is now undergoing it), but which she didn’t previously have the capacity to determinately pick out. we’ll call this wakening a. (beauty might undergo multiple wakenings, but we’re going to focus on one for now, and call it a.) given these three propositions, we can describe four possibilities. or, as we’ll somewhat inaccurately describe them, four worlds. w : h ∧ m w : h ∧ ¬m w : ¬h ∧ m w : ¬h ∧ ¬m on sunday, beauty’s credences are distributed over the algebra generated by the par- tition {h, ¬h}, i.e., {{w , w }, {w , w }}. the algebra is that course-grained because she doesn’t have the capacity to think m thoughts. and that’s because she’s not ac- quainted with the relevant haecceities. so she can’t distinguish between worlds that differ only on whether m is true. on sunday then, beauty’s credences are given by pr(h) = pr(¬h) = . stalnaker thinks we have independent reason to treat these structured entities as simply worlds. the main point of the last few sentences was that we can adopt stalnaker’s model while staying neutral on this metaphysical question. perhaps it would be better to say that individuals and times have haecceities, rather than saying centers do. i have little idea what could tell between these options, or even if there is a substantive issue here. of course worlds are considerably more detailed than this, but the extra detail is an unnecessary confusion for the current storyline. stalnaker on sleeping beauty when she wakes on monday, two things happen. first, she becomes acquainted with a. so she can now think about whether a is on monday. that is, she can now think about whether m is true. so she can now carve the possibility space more finely. indeed, now her credences can be distributed over all propositions built out of the four possibilities noted above. the second thing that happens is that beauty rules out one of these possibilities. in particular, she now knows that h ∧ ¬m, a proposition she couldn’t so much as think before, is actually false. that’s because if the coin landed heads, this very wakening could not have taken place on tuesday. stalnaker’s position on beauty’s credences uses these two facts. first beauty ‘recalibrates’ her credences to the new algebra, then she updates by conditionalising on ¬h ∨ m. if after recalibration, her credences are equally distributed over the four cells of the partition, the conditionalising on ¬h ∨ m will move pr(h) to . that is, the thirders win! but we might wonder why we use just this calibration, the one where all four cells get equal credence. we’re going to come back to this question below. but first, i want to use stalnaker’s framework to respond to an interesting objection to the thirder position. monty hall both c. s. jenkins ( ) and joseph halpern ( ) have argued that the ‘thirder’ solution is undermined by its similarity to fallacious reasoning in the monty hall case. the idea is easy enough to understand if we simply recall the monty hall problem. the agent is in one of three states s , s or s , and has reason to believe each is equally likely. she guesses which one she is in. an experimenter then selects a state that is neither the state she is in, nor the state she guessed, and tells her that she is not in that state. if she simply conditionalises on the content of the experimenter’s report, then her credence that she guessed correctly will go from to . this is a bizarre failure of reflection, so something must have gone wrong. both jenkins and halpern suggest that the violation of reflection that ‘thirders’ endorse in sleeping beauty is just as bizarre. but the sleeping beauty puzzle is not analogous to the monty hall problem. that’s because in sleeping beauty we seem forced to have a violation of reflection somewhere. let’s think a bit again about beauty’s credences on wednesday, and let’s assume that we’re trying to avoid reflection violations. then on monday (and tuesday) her credence in h is . now when beauty awakes on those days, there are three possibilities open to her. (hopefully it won’t lead to ambiguity if i re-use the name a for the awakening beauty is undergoing when thinking about h.) • a is monday and h • a is monday and ¬h • a is tuesday and ¬h the standard response is to say that the agent shouldn’t just conditionalise on the content of the experimenter’s utterance, but on the fact that the experimenter is making just that utterance. we’ll return to this idea below. stalnaker on sleeping beauty when she wakes on wednesday, she’s in a position to reflect on these possibilities. and she can rule out the second of them. that’s what she learns when she wakes and learns it is wednesday; that if ¬h, then that last awakening was on tuesday. now since that last awakening, nothing odd has happened to beauty. she hasn’t had her memories erased. she might have had her memories erased between monday and tuesday, but that’s not relevant to the time period she’s considering. moreover, she knows that she hasn’t had her memories erased. so i think she’s in a position to simply conditionalise on her new evidence. and that new evidence is simply that whatever else was going on when she was thinking about those three possibilities, she wasn’t in the second possibility. but now we face a challenge. beauty knows that wednesday will come. so if her credence in h on wednesday isn’t , then we’ll have a violation of reflection. the violation is that on sunday her credence in h is , but she knows it will go up on wednesday. and that violation is just as bad as the violation of reflection that ‘thirders’ endorse. but if she conditionalises when she wakes up on wednesday, then the only way her updated credence in h can be is if her prior credence in the first and third options above were equal. and the only way that can happen is for her credence, when a is happening, in the proposition that a is monday and ¬h is . but that’s bizarre. whether or not the thirders are right to think that she should give equal credence to that possibility as to the two others, she can’t give it credence . so reflection will fail somewhere. to see why reflection is failing in these cases, it helps to look back at the require- ments we need in order to get from conditionalisation to reflection. in rachael briggs’s careful analysis of when reflection holds, in briggs ( ), reflection is only guaranteed to hold when agents know what their evidence is. in other cases, even perfect conditionalisers may violate reflection. this assumption, namely that agents know what their evidence is, is a kind of luminosity assumption. and not surprisingly, it has been challenged by timothy williamson (williamson, , - ). what is a little more surprising is that we only need a relatively weak failure of luminosity in order to get problems for reflection. the assumption that agents know what their evidence is can be broken into two parts. • if p is part of s’s evidence, then s knows that p is part of her evidence. • if p is not part of s’s evidence, then s knows that p is not part of her evidence. the first part is, i think, implausible for reasons familiar from williamson’s work. but the second is implausible even if one doesn’t like williamson’s style of reasoning. if we think p must be true to be part of s’s evidence (as i think we should), and we think that rational agent’s can have false beliefs about anything, as also seems plausible by simple observation of how easy it is to be misled, then even a rational agent can fail to realise that p is not part of her evidence. the easiest way that can happen is if she falsely, but reasonably, believes p, and hence does not realise that due to its falsity, it is not part of her evidence. williamson provides an interesting model, based on a discussion in shin ( ), of a case where an agent does not know that something is not part of her evidence. stalnaker on sleeping beauty there are currently three possible states the agent could be in: s , s or s . an ex- periment will be run, and after the experiment the agent will get some evidence depending on which state she’s in. • if she’s in s , her evidence will rule out s . • if she’s in s , her evidence will rule out s and s . • if she’s in s , her evidence will rule out s . assume the agent knows these conditionals before the experiment is run, and now let’s assume the experiment has been run. let xry mean that y is possible given the evidence s gets in x. then we can see that r is transitive. that means that if p is part of s’s evidence, then her evidence settles that p is part of her evidence. but r is not euclidean. so it is possible that p is not part of her evidence, even though her evidence does not settle that p is not part of her evidence. in particular, if she is in s , that she isn’t in s is not part of her evidence. but for all she can tell, she’s in s . and if she’s in s , her evidence does rule out her being in s . so her evidence doesn’t settle that this is not part of her evidence. the model is obviously an abstraction from any kind of real-world case. but as we argued above, it is plausible that there are cases where an agent doesn’t know what evidence she lacks. and this kind of case makes for reflection failure. as- sume that the agent’s prior credences are (and should be) that each state is equally likely. and assume the agent conditionalises on the evidence she gets. then her credence that she’s in s will go up no matter what state she’s in. and she knows in advance this will happen. but there’s no obvious irrationality here; it’s not at all clear what kind of reflection-friendly credal dynamics would be preferably to updating by conditionalisation. so when an agent doesn’t know what evidence she lacks, reflection can fail. one way to think about the sleeping beauty case is that something like this is going on, although it isn’t quite analogous to the shin-williamson example discussed above. in that example, the agent doesn’t know what evidence she lacks at the later time. in the sleeping beauty case, we can reasonably model beauty as knowing exactly what her evidence is when she wakes up. her evidence does nothing more or less than rule out w . that’s something she didn’t know before waking up. but in a good sense she didn’t know that she didn’t know that. that’s because she was not in a position to even think about w as such. since she wasn’t in a position to think about a, couldn’t distinguish, even in thought, between w and w . so any proposition she could think about, and investigate whether she knew or not, had to include either both w and w , or include neither of them. so the only way she could know that the idea that we should update by conditionalisation on our evidence, even when we don’t know what the evidence is, has an amusing consequence in the monty hall problem. the agent guesses that she’s in si, and comes to know she’s not in sj, where i ̸= j. if she only comes to know that she’s not in sj, and not something stronger, such as knowing that she knows she’s not in sj, then she really should conditionalise on this, and her credence that her guess was correct will go up. this is the ‘mistaken’ response to the puzzle that is frequently deprecated in the literature. but since the orthodox solutions to the puzzle rely on the agent reflecting on how she came to know ¬sj, it seems that it is the right solution if she doesn’t know that she knows ¬sj. stalnaker on sleeping beauty she didn’t know {w , w , w } is if she tacitly knew she didn’t know that in virtue of knowing that she didn’t know {w , w , w , w }. but she didn’t know that she didn’t know that for the simple reason that she did know that {w , w , w , w }, i.e. the universal proposition, is true. so we have a case where beauty doesn’t know what it is she doesn’t know at the earlier time. and like cases where the agent doesn’t know what she doesn’t know at the later time, this is a case where reflection fails. so there are two reasons to be sceptical of reflection-based arguments against the ‘thirder’ solution to the sleeping beauty puzzle. • there is no plausible way for beauty’s credence in h to be on both monday and wednesday, but reflection requires this. • reflection is only plausible when agents know both what evidence they have, and what evidence they lack, throughout the story. and it is implausible that beauty satisfies this constraint, since she gains conceptual capacities during the story. but this isn’t a positive argument for the solution. i’ll conclude with a discussion of two arguments for the solution. both arguments are suggested by stalnaker’s framework, but only one of them is ultimately defensible. stalnaker on sleeping ugly when we left stalnaker’s discussion of the sleeping beauty case, we had just noticed that there was a question about why beauty should respond to being able to more finely discriminate between states by ‘recalibrating’ to a credal state where each of w through w receive equal credence. this question about calibration is crucial to the sleeping beauty puzzle because there are other post-calibration distributions of credence are are prima facie viable. perhaps, given what beauty knows about the setup, she should never have assigned any credence to h ∧ ¬m. rather, she should have made it so pr(¬h ∧ m) = pr(¬h ∧ ¬m) = , and pr(h ∧ m) = . if she does that, the conditionalising on ¬(h ∧ ¬m) won’t change a thing, and pr(h) will still be . that is, the halfers win! one argument against this, and in favour of the equally weighted calibration, is suggested by stalnaker’s ‘sleeping ugly’ example. sleeping ugly is woken up on monday and again (with erased memories) on tuesday however the coin lands. so when ugly awakes, he has the capacity to think new singular thoughts, but he doesn’t get much evidence about them. in particular, he can’t share the knowledge beauty would express by saying, “if the coin landed heads, this is monday.” now we might think it is intuitive that ugly’s credences when he wakes up and reflects on his situation should be equal over the four possibilities. moreover, all ugly does is recalibrate; since he doesn’t learn anything about which day it is, his post-awakening credence just is his recalibration. if all this is correct, and if beauty should recalibrate in the same way as ugly, then beauty should recalibrate to the ‘equally weighted calibration’. and now we’re back to victory for the thirders! stalnaker notes that this is a reason for thinking beauty does learn something when she wakes up, and so there’s a reason her credence in h changes. stalnaker on sleeping beauty but there’s little reason to believe the crucial premise about how ugly should recalibrate his credences. what we know is that ugly doesn’t have any reason to give any more credence to any one of the four possibilities than to the others. it doesn’t at all follow that he has reason to give equal credence to each, any more than in general an absence of reasons to treat one of the xs differently to the others is a reason to treat them all the same. the argument i’m considering here is similar to reasoning adam elga has em- ployed elga ( ), and which i have criticised weatherson ( ). a central focus of my criticism was that this kind of reasoning has a tendency to lead to countable additivity violations. in an important recent paper, jacob ross ( ) has shown that many thirder arguments similarly lead to countable additivity violations. he shows this by deriving what he calls the ‘generalised thirder principle’ (hereafter, gtp) from the premises of these arguments. the gtp is a principle concerning a generalised version of the sleeping beauty problem. here is ross’s description of this class of problems. let us define a sleeping beauty problem as a problem in which a fully ra- tional agent, beauty, will undergo one or more mutually indistinguish- able awakenings, and in which the number of awakenings she will un- dergo is determined by the outcome of a random process. let s be a partition of alternative hypotheses concerning the outcome of this ran- dom process. beauty knows the objective chances of each hypothesis in s, and she also knows how many time she will awaken conditional on each of these hypotheses, but she has no other relevant information. the problem is to determine how her credence should be divided among the hypotheses in s when she first awakens. (ross ms, - ) the gtp is a principle about this general class of problem. here’s how ross states it. generalized thirder principle in any standard sleeping beauty problem, upon first awakening, beauty’s credence in any given hypothesis in s must be propor- tional to the product of the hypothesis’ objective chance and the number of times beauty will awaken conditional on this hypothesis. ... [we can] express this principle formally. for any hypothesis i ∈ s, let ch(i) be the objective chance that hypothesis i is true, and let n(i) be the number of times beauty awakens if i is true. let p be the beauty’s credence function upon first awak- ening. the gtp states ... for all i, j ∈ s, p(i) p(j) = n(i)ch(i) n(j)ch(j) whenever ch(j) > . (ross ms, - ) compare this argument for giving nothing to charity. there are thousands of worthwhile charities, and i have no reason to give more to one than any of the others. but i can’t afford to give large equal amounts to each, and if i gave small equal amounts to each, the administrative costs would mean my donation has no effect. so i should treat each equally, and the only sensible practical way to do this is to give none to each. note that you really don’t have to think one charity is more worthy than the others to think this is a bad argument; sometimes we just have to make arbitrary choices. stalnaker on sleeping beauty the argument i’m considering seems to be committed to the gtp. in a generalised sleeping beauty problem, we can imagine a version of sleeping ugly who will awake every day that beauty might awake. the reasoning that leads one to think that ugly should give equal credence to each of the two days in the original sleeping beauty case seems to generalise to imply that ugly should give equal credence to each day in this more general case. but if in the general example beauty calibrates to match these credences of ugly, then conditionalises on the information she receives, then she’ll end up endorsing the gtp. that’s an unhappy outcome. it would be better to have an argument for the solution that doesn’t imply the gtp. i’m going to argue that when beauty wakes up her credences should satisfy the following two premises. (as always, i use a to name the awakening that beauty is now undergoing, and i’m using cr for her credence function on waking.) p : cr(a is monday and h) = cr(a is tuesday and ¬h) p : cr(a is monday and h) = cr(a is monday and ¬h) these constraints imply, given what beauty knows about the setup, that cr(h) = . the arguments for each premise are quite different. the argument for p is one i mentioned above, so i’ll just sketch it quickly here. on wednesday, beauty’s credence in h should be back to . but what she learns on wednesday is ¬(a is on monday and ¬h). so on monday, her credence in h conditional on ¬(a is on monday and ¬h) should be . but given what beauty knows about the setup of the problem, this immediately implies p . the argument for p requires a slightly more fanciful version of the example. imagine that on sunday night, beauty is visited by a time traveller from monday who comes back with a videotape of her waking on monday, and tells her that it was taken on monday. so beauty now has the capacity to think about this very awakening, i.e., a. this doesn’t seem to affect her credences in h, it should still be . now imagine that her memory of this visit is erased overnight, so when she wakes up on monday her situation is just like in the original sleeping beauty problem. call cr her credence function on sunday after meeting the time traveller. and call cr her credence function on monday after she wakes up and reflects on her situation. it seems the only relevant difference between the situation on sunday and the situation on monday is that beauty has lost the information that a is on monday. the following principle about situations where an agent loses information seems plausible. if crold is the pre-loss credence function, and crnew is the post-loss credence function, and e is the information lost, then • crold(p) = crnew(p|e) the idea here is that information loss is a sort of reverse conditionalisation. applying this, we get that cr (h) = cr (h|a is monday), so cr ((h|a is monday) = , so cr (a is monday and h) = cr (a is monday and ¬h). and since the situation on monday in the revised problem, i.e., the situation when beauty’s credence function is cr is just like the situation in the original sleeping beauty problem on monday, stalnaker on sleeping beauty it follows that p is true in the original problem. and from p and p , it follows that the thirder solution is right. but note a limitation of this solution. when beauty wakes on tuesday her cre- dence function is defined over a different algebra of propositions to what it was defined over after meeting the time traveller. so there’s no time travel based argu- ment that her credences on tuesday should satisfy p , or indeed that on tuesday her credence in h should be . (for similar reasons, this kind of reason does not support the gtp.) one might try and argue that beauty’s situation on tuesday is indistinguishable from her situation on monday, and so she should have the same credences on tues- day. both the premise and the inference here seem dubious. on tuesday, beauty knows different singular propositions, so the situation isn’t clearly indistinguishable. but more importantly, it is implausible that indistinguishability implies same cre- dences. the relation should have the same credences in is a transitive and symmetric relation between states. the relation is indistinguishable from is neither transitive nor symmetric. so i suspect that the kind of arguments developed here leave it an open question what beauty’s credences should be on tuesday, and indeed whether there is a unique value for what her credences then should be. references briggs, rachael, ( ). “distorted reflection.” philosophical review : - , doi: . / - - . ( ) egan, andy, ( ). “second-order predication and the metaphysics of proper- ties.” australasian journal of philosophy : - , doi: . / . ( ) egan, andy, hawthorne, john, and weatherson, & brian, ( ). “epistemic modals in context.” in gerhard preyer and georg peter (eds.), contextualism in philosophy: knowledge, meaning, and truth, - . oxford: oxford university press. ( ) elga, adam, ( ). “self-locating belief and the sleeping beauty problem.” analysis : - , doi: . /analys/ . . . ( ) —, ( ). “defeating dr. evil with self-locating belief.” philosophy and phe- nomenological research : - , doi: . /j. - . .tb .x. ( ) halpern, joseph, ( ). “sleeping beauty reconsidered: conditioning and re- flection in asynchronous systems.” in oxford studies in epistemology, volume , - . oxford: oxford university press. ( ) jenkins, c. s., ( ). “sleeping beauty: a wake-up call.” philosophica mathe- matica : - , doi: . /philmat/nki . ( ) lewis, david, ( ). “attitudes de dicto and de se.” philosophical review : - , doi: . / . reprinted in philosophical papers, volume i, pp. - . ( ) http://dx.doi.org/ . / - - http://dx.doi.org/ . / http://dx.doi.org/ . /analys/ . . http://dx.doi.org/ . /j. - . .tb .x http://dx.doi.org/ . /philmat/nki http://dx.doi.org/ . / stalnaker on sleeping beauty ross, jacob, ( ). “sleeping beauty, countable additivity, and rational dilem- mas.” philosophical review : - , doi: . / - - . ( ) shin, hyun song ( ). “non-partitional information on dynamic state spaces and the possibility of speculation.” working paper - , center for research on economic and social theory, univesity of michigan. ( ) stalnaker, robert, ( ). our knowledge of the internal world. oxford: oxford university press. ( ) titlebaum, michael, ( ). “the relevance of self-locating beliefs.” philosoph- ical review : - , doi: . / - - . ( ) weatherson, brian, ( ). “can we do without pragmatic encroachment?” philosophical perspectives : - , doi: . /j. - . . .x. ( ) williamson, timothy, ( ). knowledge and its limits. oxford university press. ( ) http://dx.doi.org/ . / - - http://dx.doi.org/ . / - - http://dx.doi.org/ . /j. - . . .x stalnaker on sleeping beauty stalnaker on self-location monty hall stalnaker on sleeping ugly book review w. l. mang, mein schönheitsbuch (my beauty book)—in german trias, stuttgart, , pages, isbn: - - - , $ . usd leo clodius received: april /accepted: april /published online: june # springer-verlag in the foreword, the author claims to be the pioneer of “beauty surgery” in germany and draws attention to the nonreversible trend of the general attitude to the rapid increase in this kind of lifestyle surgery. good looks and fitness, according to the author, seem to guarantee rapid success. this is the principal motivation for the author’s suggestions. this book was mainly written to provide information for patients interested in undergoing cosmetic surgery and to be treated at the clinic of the author. the contents provide both advice for useful conservative health strategies (e.g., antiaging, well-being, nutrition) and for understanding the possibilities and risks of the various cosmetic surgical interventions. whoever can master the german language and is interested in improving his or her personal appearance will find some very useful information in this book. l. clodius (*) zürich, switzerland e-mail: eurjplastsurg@juno.com eur j plast surg ( ) : doi . /s - - - w. l. mang, mein schönheitsbuch (my beauty book)—in german << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated v % \ eci\ ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /perceptual /detectblends true /detectcurves . /colorconversionstrategy /srgb /dothumbnails true /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize true /opm /parsedsccomments true /parsedsccommentsfordocinfo true /preservecopypage true /preservedicmykvalues true /preserveepsinfo true /preserveflatness true /preservehalftoneinfo false /preserveopicomments false /preserveoverprintsettings true /startpage /subsetfonts false /transferfunctioninfo /apply /ucrandbginfo /preserve /useprologue false /colorsettingsfile () /alwaysembed [ true ] /neverembed [ true ] /antialiascolorimages false /cropcolorimages true /colorimageminresolution /colorimageminresolutionpolicy /warning /downsamplecolorimages true /colorimagedownsampletype /bicubic /colorimageresolution /colorimagedepth - 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/monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /description << /chs /cht /dan /esp /fra /ita /jpn /kor /nld (gebruik deze instellingen om adobe pdf-documenten te maken die zijn geoptimaliseerd voor weergave op een beeldscherm, e-mail en internet. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /ptb /suo /sve /enu (use these settings to create adobe pdf documents best suited for on-screen display, e-mail, and the internet. created pdf documents can be opened with acrobat and adobe reader . and later.) /deu >> /namespace [ (adobe) (common) ( . ) ] /othernamespaces [ << /asreaderspreads false /cropimagestoframes true /errorcontrol /warnandcontinue /flattenerignorespreadoverrides false /includeguidesgrids false /includenonprinting false /includeslug false /namespace [ (adobe) (indesign) ( . ) ] /omitplacedbitmaps false /omitplacedeps false /omitplacedpdf false /simulateoverprint /legacy >> << /addbleedmarks false /addcolorbars false /addcropmarks false /addpageinfo false /addregmarks false /convertcolors /converttorgb /destinationprofilename (srgb iec - . ) /destinationprofileselector /usename /downsample bitimages true /flattenerpreset << /presetselector /mediumresolution >> /formelements false /generatestructure false /includebookmarks false /includehyperlinks false /includeinteractive false /includelayers false /includeprofiles true /multimediahandling /useobjectsettings /namespace [ (adobe) (creativesuite) ( . ) ] /pdfxoutputintentprofileselector /na /preserveediting false /untaggedcmykhandling /usedocumentprofile /untaggedrgbhandling /usedocumentprofile /usedocumentbleed false >> ] >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice cern-th/ - shep - hep-ph/ spectator effects in inclusive decays of beauty hadrons m. neubert and c.t. sachrajda∗ theory division, cern, ch- geneva , switzerland abstract we present a model-independent study of spectator effects, which are responsible for the lifetime differences between beauty hadrons. these effects can be parametrized in terms of hadronic matrix elements of four four-quark operators. for b mesons, the coefficients of the non-factorizable operators turn out to be much larger than those of the factorizable ones, limiting considerably the usefulness of the vacuum insertion approxima- tion. non-factorizable contributions to the lifetime ratio τ(b−)/τ(bd) could naturally be of order – %, and not even the sign of these contribu- tions can be predicted at present. in the case of the Λb baryon, heavy-quark symmetry is used to reduce the number of independent matrix elements from four to two. in order to explain the large deviation from unity in the experimental result for τ(Λb)/τ(bd), it is necessary that these baryon matrix elements be much larger than those estimated in quark models. we have also reexamined the theoretical predictions for the semileptonic branching ratio of b mesons and charm counting, finding that, given the present theoretical and experimental uncertainties, there is no significant discrepancy with experiment. (revised version) cern-th/ - september ∗on leave from the department of physics, university of southampton, southampton so bj, uk introduction in this paper we study “spectator effects” in inclusive decays of beauty hadrons. these effects involve the participation of the light constituents in the decay and thus contribute to the differences in the decay widths and lifetimes of different species of beauty hadrons. indeed, one of our goals is to understand theoretically the experimental results for the lifetime ratios [ ]: τ(b−) τ(bd) = . ± . , τ(bs) τ(bd) = . ± . , τ(Λb) τ(bd) = . ± . . ( ) here τ(bs) refers to the average bs-meson lifetime. our study is performed in the framework of the heavy-quark expansion, in which these ratios are computed as series in inverse powers of the mass of the b quark [ ]–[ ] (for recent reviews, see refs. [ , ]). the leading term of this expansion corresponds to the decay of a free b quark. this term is universal, contributing equally to the lifetimes of all beauty hadrons. remarkably, the first correction to this result is of order (Λqcd/mb) [ , ]. this leads to the theoretical predictions (see section below) τ(b−) τ(bd) = + o( /m b ) , τ(bs) τ(bd) = ( . ± . ) + o( /m b) , τ(Λb) τ(bd) = . + o( /m b ) . ( ) the deviation from this expectation for τ(Λb)/τ(bd) is striking, and is the prin- ciple motivation for this study. spectator effects, i.e. contributions from decays in which a light constituent quark also participates in the weak process, have first been considered in refs. [ ]– [ ]. for decays of heavy particles, these effects are strongly suppressed due to the need for the b quark and a light quark in the heavy hadron to be close together (i.e. from a factor of the “wave-function at the origin”). as the portion of the volume that the b quark occupies inside the hadron is of order (Λqcd/mb) , spectator effects appear only at third order in the heavy-quark expansion, and it might seem safe to neglect them altogether. however, as a result of the difference in the phase-space for → -body reactions as compared to → -body decays, these effects are enhanced by a factor of order π . it is conceivable that they could be larger than the terms of order (Λqcd/mb) included in ( ). moreover, spectator effects explicitly differentiate between different species of beauty hadrons. in order to understand the structure of lifetime differences, it is therefore important to reconsider the analysis of such effects. the striking experimental result for the short Λb lifetime gives an additional motivation to such a study. previous studies of spectator effects in the decays of beauty hadrons [ ] were performed using the formalism developed in refs. [ ]–[ ] and made two simpli- fying assumptions: first, the hadronic matrix elements of these operators were estimated employing the vacuum insertion approximation [ ] for mesons and quark models [ , ] for baryons, and secondly the mass of the charm quark was neglected in the calculation of the coefficients of the four-quark operators in the heavy-quark expansion. in order to explore the acceptable range of theoretical predictions, we do not impose factorization or quark-model approximations on the hadronic matrix elements. instead, we parametrize them by a set of hadronic parameters and see how the lifetime ratios depend upon them. one of our main conclusions is that only a detailed field-theoretic calculation of the relevant ma- trix elements can lead to reliable predictions. in addition, we derive the exact expressions for the coefficients as functions of the charm-quark mass. the semileptonic branching ratio of b mesons has also received considerable attention. for many years it appeared that the theoretical predictions for this quantity [ ]–[ ] lay above the measured value. more recently, the theoretical predictions have been refined by including exact expressions for the o(αs) cor- rections [ ]. using the results of these calculations, we present a new analysis of the semileptonic branching ratio bsl and the average charm multiplicity nc in b decays. we find that the freedom in the choice of the renormalization scale (which reflects the ignorance of higher-order perturbative corrections) allows us to obtain consistent predictions for both quantities simultaneously. we also cal- culate the spectator contributions to bsl and nc and show that they could change the semileptonic branching ratio by an amount of order %, whereas their effect on nc is negligible. in section , we discuss the heavy-quark expansion for inclusive decay rates, and we present our results for the contributions arising from spectator effects. in section , we introduce a set of hadronic parameters defined in terms of the relevant four-quark operator matrix elements between b-meson and Λb-baryon states. heavy-quark symmetry is used to derive some new relations between the baryonic matrix elements of these operators. in section , we then discuss the phenomenological implications of our results for the understanding of beauty lifetimes. we also present a critical discussion of previous estimates of spectator effects based on the factorization approximation. a detailed discussion of the semileptonic branching ratio of b mesons is presented in section . section contains the conclusions. the renormalization of the operators and parame- ters describing the spectator effects, and the behaviour of these parameters with respect to the large-nc limit, are discussed in appendix a, while appendix b contains details about the calculation of the semileptonic branching ratio. the reader who is primarily interested in the phenomenological implications of our analysis can omit sections and and proceed directly to sections , and , which are written in a self-contained way. heavy-quark expansion inclusive decay rates, which determine the probability of the decay of a particle into the sum of all possible final states with a given set of quantum numbers {f}, have two advantages from the theoretical point of view: first, bound-state effects related to the initial state can be accounted for in a systematic way using the heavy-quark expansion; secondly, the fact that the final state consists of a sum over many hadronic channels eliminates bound-state effects related to the properties of individual hadrons. this second feature is based on the hypothesis of quark–hadron duality, i.e. the assumption that cross sections and decay rates are calculable in qcd after a “smearing” procedure has been applied [ ]. we shall not discuss this hypothesis here; however, if after the non-perturbative eval- uation of the spectator effects discussed in our analysis there remain significant discrepancies between theory and experiment (for the lifetime ratio τ(Λb)/τ(bd), in particular), one may have to seriously question the assumption of duality. a recent study of inclusive b decays, in which duality violations are invoked to add non-perturbative contributions of order Λqcd/mb not present in the heavy-quark expansion, can be found in ref. [ ]. using the optical theorem, the inclusive decay width of a hadron hb containing a b quark can be written as the forward matrix element of the imaginary part of the transition operator t, Γ(hb → x) = mhb im〈hb|t |hb〉 = mhb 〈hb|Γ |hb〉 , ( ) where t is given by t = i ∫ d xt{leff (x),leff ( )} . ( ) for the case of semileptonic and non-leptonic decays, the effective weak la- grangian, renormalized at the scale µ = mb, is leff = − gf √ vcb { c (mb) [ d̄′lγµul c̄lγ µbl + s̄ ′ lγµcl c̄lγ µbl ] + c (mb) [ c̄lγµul d̄ ′ lγ µbl + c̄lγµcl s̄ ′ lγ µbl ] + ∑ `=e,µ,τ ¯̀ lγµν` c̄lγ µbl } + h.c. , ( ) where ql = ( −γ )q denotes a left-handed quark field, d ′ = d cos θc + s sin θc and s′ = s cos θc − d sin θc are the cabibbo-rotated down- and strange-quark fields (sin θc ' . ), and we have neglected b → u transitions. the wilson coefficients c and c take into account the qcd corrections arising from the fact that the effective lagrangian is written at a renormalization scale µ = mb rather than mw . they can be calculated in perturbation theory. the combinations c± = c ±c have a multiplicative evolution under change of the renormalization scale. to leading order, they are given by [ ]–[ ] c±(mb) = ( αs(mw ) αs(mb) )a± , a− = − a+ = − − nf . ( ) in the numerical analysis we shall take the values c+(mb) ' . and c−(mb) = /c +(mb) ' . , corresponding to αs(mz) = . . since the energy release in the decay of a b quark is large, it is possible to construct an operator product expansion (ope) for the bilocal transition operator ( ), in which it is expanded as a series of local operators with increasing dimension, whose coefficients contain inverse powers of the b-quark mass. the operator with the lowest dimension is b̄b. there is no independent operator with dimension four, since the only candidate, b̄ i /db, can be reduced to b̄b by using the equations of motion [ , ]. the first new operator is b̄gsσµνg µνb and has dimension five. thus, any inclusive decay rate of a hadron hb can be written in the form Γ(hb → xf ) = g fm b π mhb { c f 〈hb| b̄b |hb〉 + c f 〈hb| b̄gsσµνg µνb |hb〉 m b + . . . } , ( ) where cfn are calculable coefficient functions (which also contain the relevant ckm matrix elements) depending on the quantum numbers {f} of the final state. for semileptonic and non-leptonic decays, the coefficients c f have been calculated at one-loop order [ , , ], and the coefficients c f at tree level [ , ]. in the next step, the forward matrix elements of the local operators in the ope are systematically expanded in inverse powers of the b-quark mass, using the heavy-quark effective theory (hqet) [ ]. one finds [ , ] mhb 〈hb| b̄b |hb〉 = − µ π(hb) −µ g(hb) m b + o( /m b ) , mhb 〈hb| b̄gsσµνg µνb |hb〉 = µ g(hb) + o( /mb) , ( ) where µ π(hb) and µ g(hb) parametrize the matrix elements of the kinetic-energy and the chromo-magnetic operators, respectively. the purpose of doing this ex- pansion is that whereas the matrix elements in ( ) contain an implicit dependence on the b-quark mass, the parameters appearing on the right-hand side of ( ) are independent of mb (modulo logarithms). these parameters can be determined, to some extent, from the spectrum of heavy hadron states. below we shall need the values µ π(Λb) −µ π(b) = −( . ± . ) gev , µ g(b) = (m b∗ −m b) ' . gev , µ g(Λb) = . ( ) the difference µ π(Λb) −µ π(b) can be extracted from the mass formula [ , ] (mΛb −mΛc)−(mb −md) = [ µ π(b)−µ π(Λb) ]( mc − mb ) + o( /m q) , ( ) where mb = (mb + mb∗) and md = (md + md∗) denote the spin-averaged meson masses. with mΛb = ( ± ) mev [ ], this relation leads to the value quoted above. to order /m b in the heavy-quark expansion, the lifetime ratio for two beauty hadrons is given by τ(h ( ) b ) τ(h ( ) b ) = + µ π(h ( ) b ) −µ π(h ( ) b ) m b + cg µ g(h ( ) b ) −µ g(h ( ) b ) m b + o( /m b ) , ( ) where cg ' . can be obtained using the results of refs. [ , ]. using then the values given in ( ), and assuming that in the case of the bs meson su( )- breaking effects in the values of the matrix elements are of order %, we arrive at the predictions given in ( ). note that in taking a ratio of lifetimes, theoretical uncertainties related to the values of the b-quark mass (including renormalon ambiguities) and ckm elements cancel to a large extent. it is for this reason that we restrict our discussion to the calculation of ratios of lifetimes and decay rates. the first two terms in the heavy-quark expansion ( ) arise from decays in which the (light) spectator quarks interact only softly. additional contributions of this type appear at the next order through gluonic operators of dimension six, such as b̄γµ(idνg µν)b. since matrix elements of these operators are blind to the flavour of the spectator quarks, they can be safely neglected in our anal- ysis. “hard” spectator effects manifest themselves first in the matrix elements of four-quark operators of dimension six. some examples of the corresponding contributions to the transition operator t are shown in figure . they only appear in the heavy-quark expansion of non-leptonic decay rates. since these contributions arise from one-loop rather than two-loop diagrams, they receive a phase-space enhancement factor of order π relative to the other terms in the heavy-quark expansion. this is no longer true if b → u transitions or the decays of the bc meson are considered. �b �i q �q �i b b b c u d d b bc d u u figure : spectator contributions to the transition operator t (left), and the corresponding operator in the ope (right). here Γi denotes some combination of dirac and colour matrices. we have calculated the coefficients of the corresponding four-quark operators at tree level, including for the first time the dependence on the mass of the charm quark. this extends the results obtained in ref. [ ]. we find that the corresponding contributions to the non-leptonic widths of mesons and baryons containing a b quark are given by the matrix elements of the local operator Γspec = g fm b π |vcb| ( −z) {( c c + nc (c + c ) ) ouv−a + (c + c ) t u v−a } − g fm b π |vcb| ( −z) {( c c + nc c + nc c )[( + z ) od ′ v−a − ( + z) o d′ s−p ] + c [( + z ) td ′ v−a − ( + z) t d′ s−p ]} − g fm b π |vcb| √ − z {( c c + nc c + nc c )[ ( −z) os ′ v−a − ( + z) o s′ s−p ] + c [ ( −z) ts ′ v−a − ( + z) t s′ s−p ]} , ( ) where z = m c/m b, and nc= is the number of colours. the local four-quark operators appearing in this expression are defined by o q v−a = b̄lγµql q̄lγ µbl , o q s−p = b̄r ql q̄l br , t q v−a = b̄lγµtaql q̄lγ µtabl , t q s−p = b̄r taql q̄l tabr , ( ) where ta = λa/ are the generators of colour su( ). for dimensional reasons, Γspec is proportional to m b rather than m b, in accordance with the fact that spectator effects contribute at third order in the heavy-quark expansion. the first term in ( ) arises from the upper diagram in figure , whereas the second and third terms come from the contributions of the lower diagram with a cū and cc̄ quark pair in the loop. we note that in the limit z = our results agree with ref. [ ], and with the corresponding expression derived for the lifetimes of charm hadrons in refs. [ ]–[ ]. the operators in ( ) are renormalized at the scale mb, which will be im- plicit in our discussion below. this choice has the advantage that logarithms of the type [αs ln(mb/µhad)] n, where µhad is a typical hadronic scale, reside en- tirely in the hadronic matrix elements of the renormalized operators. using the renormalization-group equations, the expressions presented in this paper can be rewritten in terms of operators renormalized at any other scale. however, at present the scale dependence of the renormalized operators below the scale mb is known only to leading logarithmic order [ , ]. it is discussed in detail in ap- pendix a. since here we shall treat the matrix elements as unknown parameters, we can avoid all uncertainties related to the operator evolution by working at the scale mb. the hadronic matrix elements of the four-quark operators in ( ) contain the non-perturbative physics of the spectator contributions to inclusive decays of beauty hadrons. however, the same operators also contribute to the decay of the b quark, through tadpole diagrams in which the light-quark fields are contracted in a loop. these “non-spectator” contributions are independent of the flavour of the light quark q and thus contribute equally to the decay widths of all beauty hadrons. they are not of interest to our discussion here. in order to isolate the true spectator effects, we shall implicitly assume a normal ordering of the four- quark operators, which has the effect of subtracting tadpole-like diagrams. in practice, this is equivalent to choosing a particular renormalization prescription for the operators. alternatively, one may isolate the spectator effects by con- sidering light-quark flavour non-singlet combinations of the operators; thus, for example, for matrix elements between bd states one could take (o d −ou) and (td −tu) instead of od and td. parametrization of the matrix elements in previous analyses [ ], [ ]–[ ], the hadronic matrix elements of the four-quark operators in ( ) have been estimated making simplifying assumptions. here we shall avoid such assumptions and, without any loss of generality, express the relevant matrix elements in terms of a set of hadronic parameters. clearly, such an approach has less predictive power; however, it does allow us to find the range of predictions that can be made in a model-independent way. in view of the apparent discrepancy between theory and experiment for the Λb lifetime, we find it worth while to question the model-dependent assumptions made in earlier analyses. ultimately, the relevant hadronic parameters may be calculated using some field-theoretic approach such as lattice gauge theory or qcd sum rules. it has also been suggested that combinations of these parameters may be extracted from a precise measurement of the lepton spectrum in the endpoint region of semileptonic b decays, or from a study of spectator effects in charm decays [ ]. . mesonic matrix elements for matrix elements of the four-quark operators between b-meson states, we define parameters bi and εi such that: mbq 〈bq|o q v−a |bq〉 ≡ f bqmbq b , mbq 〈bq|o q s−p |bq〉 ≡ f bqmbq b , mbq 〈bq|t q v−a |bq〉 ≡ f bqmbq ε , mbq 〈bq|t q s−p |bq〉 ≡ f bqmbq ε . ( ) this definition is inspired by the vacuum insertion (or factorization) approxi- mation [ ], according to which the matrix elements of four-quark operators are evaluated by inserting the vacuum inside the current products. this leads to 〈bq|o q v−a |bq〉 = ( mb + mq mb ) 〈bq|o q s−p |bq〉 = f bqm bq , 〈bq|t q v−a |bq〉 = 〈bq|t q s−p |bq〉 = , ( ) where fbq is the decay constant of the bq meson, defined as 〈 | q̄ γµγ b |bq(p)〉 = ifbq p µ . ( ) hence, the factorization approximation corresponds to setting bi = and εi = at some scale µ (which in general will be different from our adopted choice µ = mb), where the approximation is believed to be valid. the exact values of the hadronic parameters are not yet known. however, as discussed in appendix a, in the large-nc limit bi = o( ) , εi = o( /nc) . ( ) an estimate of the parameters εi using qcd sum rules has been obtained by chernyak, who finds that ε ≈− . and ε ≈ [ ]. in terms of the parameters bi and εi, the matrix elements of the operator Γspec in ( ) are: mb 〈b−|Γspec |b −〉 = Γ ηspec ( −z) { ( c + − c −) b + (c + + c −) ε } , mb 〈bd|Γspec |bd〉 = −Γ ηspec ( −z) cos θc { ( c+ −c−) [( + z ) b − ( + z) b ] + (c+ + c−) [( + z ) ε − ( + z) ε ]} − Γ ηspec √ − z sin θc { ( c+ −c−) [ ( −z) b − ( + z) b ] + (c+ + c−) [ ( −z) ε − ( + z) ε ]} , ( ) where c± = c ± c , and Γ = g fm b π |vcb| , ηspec = π f bmb m b . ( ) the spectator contribution to the width of the bs meson is obtained from that of the bd meson by the replacements sin θc ↔ cos θc and fb,mb → fbs,mbs. of course, the values of the parameters bi and εi for the bs meson will also differ from those for the bd meson due to su( )-breaking effects. two remarks are in order regarding the result ( ). the first concerns the expected order of magnitude of the spectator contributions to the total decay width of a b meson. at leading order in the heavy-quark expansion, the total width of a beauty hadron is Γtot ' . × Γ , where the numerical factor arises from the phase-space contributions of the semileptonic and non-leptonic channels (we use z = . ) [ , ]. it follows that Γspec Γtot ∼ ηspec ∼ ( πfb mb ) ∼ % . ( ) the second remark concerns the structure of the coefficients in ( ). given that c+ ' . and c− ' . , one observes that the coefficients of the colour singlet–singlet operators are one to two orders of magnitude smaller than those of the colour octet–octet operators. this implies that at the scale mb even small deviations from the factorization approximation can have a sizeable impact on the results. . baryonic matrix elements next we study the matrix elements of the four-quark operators between Λb-baryon states. since the Λb is an iso-singlet, the matrix elements of the operators with q = u or d are the same, and below we drop this label. in the case of baryons, we find it convenient to use the colour identity (ta)αβ (ta)γδ = δαδ δγβ − nc δαβ δγδ ( ) to rewrite t = − o + õ and introduce the operators (i,j are colour indices) õv−a = b̄ i lγµq j l q̄ j lγ µbil , õs−p = b̄ i r q j l q̄ j l b i r . ( ) instead of tv−a and ts−p . the heavy-quark spin symmetry, i.e. the fact that interactions with the spin of the heavy quark decouple as the heavy-quark mass tends to infinity, allows us to derive two relations between the matrix elements of the four-quark operators between Λb-baryon states. to find these relations, we note that the following matrix element vanishes in the limit mb →∞: mΛb 〈Λb| b̄ iγµγ b j q̄klγ µqll |Λb〉 = o( /mb) . ( ) the physical argument for this is that, because of the spin symmetry for heavy quarks, the matrix elements for left-handed and right-handed b quarks must be the same. the above result then follows since b̄γµγ b = b̄rγµbr − blγµbl. a more formal argument can be given using the covariant tensor formalism of the hqet [ , ] to show that the matrix element in ( ) is proportional to 〈 sb · slight〉 = sΛb (sΛb + ) −sb(sb + ) −slight(slight + ) = , ( ) since, in the heavy-quark limit, the light degrees of freedom are in a state with total spin zero. using the fierz identity b̄iγµγ b j q̄klγ µqll = − b̄ i r q l l q̄ k l b j r − b̄ i lγµq l l q̄ k lγ µb j l , ( ) we then obtain the relations mΛb 〈Λb|os−p |Λb〉 = − mΛb 〈Λb|ov−a |Λb〉 + o( /mb) , mΛb 〈Λb|õs−p |Λb〉 = − mΛb 〈Λb|õv−a |Λb〉 + o( /mb) . ( ) the corrections of order /mb to these relations contribute at order /m b in the heavy-quark expansion and so are negligible to the order we work in. this leaves us with two independent matrix elements of the operators ov−a and õv−a. the analogue of the factorization approximation in the case of baryons is the valence- quark assumption, in which the colour of the quark fields in the operators is identified with the colour of the quarks inside the baryon. since the colour wave function for a baryon is totally antisymmetric, the matrix elements of ov−a and õv−a differ in this approximation only by a sign. hence, we define a parameter b̃ by 〈Λb|õv−a |Λb〉≡−b̃ 〈Λb|ov−a |Λb〉 , ( ) with b̃ = in the valence-quark approximation. for the baryon matrix element of ov−a itself, our parametrization is guided by the quark model. we write mΛb 〈Λb|ov−a |Λb〉≡− f bmb r , ( ) where in the quark model r is the ratio of the squares of the wave functions determining the probability to find a light quark at the location of the b quark inside the Λb baryon and the b meson, i.e. [ , ] r = |ψΛbbq ( )| |ψ bq bq̄ ( )| . ( ) guberina et al. have estimated the ratio r for charm decays and find r ' . in the bag model, and r ' . in the non-relativistic quark model [ ]. this latter estimate has been used in more recent work on beauty decays [ ]. a similar result, r ∼ . – . , has been obtained by colangelo and fazio using qcd sum rules [ ]. recently, rosner has criticized the existing quark-model estimates of r. assuming that the wave functions of the Λb and Σb baryons are the same, he argues that the wave-function ratio should be estimated from the ratio of the spin splittings between Σb and Σ ∗ b baryons and b and b ∗ mesons [ ]. this leads to r = m Σ∗ b −m Σb m b∗ −m b . ( ) if the baryon splitting is taken to be m Σ∗ b − m Σb ' m Σ∗c − m Σc = ( . ± . ) gev , this leads to r ' . ± . . if, on the other hand, one uses the preliminary result mΣ∗ b −mΣb = ( ± ) mev reported by the delphi collab- oration [ ], one obtains r ' . ± . . we conclude that it is conceivable that r ∼ , i.e. larger than previous estimates. in terms of these parameters, the matrix element of Γspec is given by mΛb 〈Λb|Γspec |Λb〉 = Γ ηspec r { ( −z) [ (c − − c +) + (c − + c +) b̃ ] − [ ( −z) ( + z) cos θc + √ − z sin θc ] × [ (c−− c+)( c+ − c−) + (c− + c+) b̃ ]} . ( ) . numerical results to illustrate the main features of our results, we calculate the coefficients of the hadronic parameters bi, εi, and r and b̃ r in the matrix elements ( ) and ( ) in units of Γ ηspec. in order to study the dependence on the mass ratio z = (mc/mb) , we first keep the values of the wilson coefficients in the effective lagrangian fixed and vary the mass ratio in the range z = . ± . . this leads to the numbers shown in table , where the variation with z is indicated as a change in the last digit(s). note that for mesons the coefficients of the parameters bi are much smaller than those of the parameters εi. it is apparent that the results are rather stable with respect to the precise value of z. from now on we shall always use the central value z = . , which is obtained, for instance, for mc = . gev and mb = . gev. table : coefficients of the hadronic parameters obtained for z = . ± . . the values c+ = . and c− = . are kept fixed. hb b b ε ε r b̃ r b− − . ( ) — . ( ) — bd − . ( ) . ( ) − . ( ) . ( ) bs − . ( ) . ( ) − . ( ) . ( ) Λb . ( ) . ( ) as another check on the stability of the results we present in table the coefficients obtained using different “matching” procedures. to this end, we renormalize the wilson coefficients c+ and c− of the effective lagrangian at a scale µ different from mb. thus c+ and c− are modified by replacing mb by µ in ( ). this gives us predictions in terms of operators renormalized at µ, which we then rewrite in terms of those defined at mb by using the evolution equations given in appendix a. thus, the meaning of the hadronic parameters is the same as before, and the differences between the numerical results can be viewed as an estimate of unknown higher-order perturbative corrections, which we neglect throughout this paper. the coefficients of the parameters bi for mesons, as well as of the parameters r and b̃ r for the Λb baryon, show a significant scale dependence. to reduce this dependence would require a full next-to-leading order calculation of radiative corrections, which is beyond the scope of this paper. phenomenology of beauty lifetimes we shall now discuss the phenomenological implications of our results for the calculation of beauty lifetime ratios. the spectator contributions to the decay widths of bq mesons and of the Λb baryon are described by a set of hadronic table : coefficients of the hadronic parameters obtained for the matching scales µ = mb/ , mb and mb, with mb = . gev. the value z = . is kept fixed. hb µ b b ε ε r b̃ r mb/ − . — . — b− mb − . — . — mb + . — . — mb/ − . . − . . bd mb − . . − . . mb − . . − . . mb/ − . . − . . bs mb − . . − . . mb − . . − . . mb/ . . Λb mb . . mb . . parameters: b , and ε , for mesons, and r and b̃ for baryons. the explicit dependence of the decay rates on these quantities is shown in ( ) and ( ). the numerical values of the coefficients multiplying the hadronic parameters are given in table for three different choices of the matching scale µ. for the numerical analysis we need the value of the parameter ηspec defined in ( ). we take fb = mev and mb = . gev, so that ηspec ' . , and absorb the uncertainty in ηspec into the values of the hadronic parameters. . lifetime ratio τ(b−)/τ(bd) we start by discussing the lifetime ratio of the charged and neutral b mesons. because of isospin symmetry, the lifetimes of these states are the same at order /m b in the heavy-quark expansion, and differences arise only from spectator effects. if we write τ(b−) τ(bd) = + k b + k b + k ε + k ε , ( ) the coefficients ki take the values shown in table . the most striking feature of this result is the large imbalance between the coefficients of the parameters bi and εi, which parametrize the matrix elements of colour singlet–singlet and colour octet–octet operators, respectively. with εi of order /nc, it is conceivable that the non-factorizable contributions actually dominate the result. thus, without a detailed calculation of the parameters εi no reliable prediction can be obtained. in this conclusion we disagree with the authors of ref. [ ], who use factorization (at a low hadronic scale) to argue that τ(b−)/τ(bd) must exceed unity by an amount of order %. we will return to this in section . below. table : coefficients ki appearing in ( ). µ k k k k mb/ + . . − . . mb + . . − . . mb − . . − . . the experimental value of the lifetime ratio given in ( ) can be employed to constrain a certain combination of the parameters: ε = k [ ( . ± . ) −k b −k b −k ε ] . ( ) with the values of the coefficients given in table , this relation implies ε ' . ε + δ , ( ) where we expect |δ| < . . this becomes a particularly useful constraint if the parameters εi turn out to be large. below, we shall use ( ) to eliminate ε from our predictions for spectator effects. . lifetime ratio τ(bs)/τ(bd) in the limit where su( )-breaking effects are neglected, the spectator contribu- tions to the decay widths of bs and bd mesons are too similar to produce an observable lifetime difference (see table ). the corresponding contributions to the lifetime ratio τ(bs)/τ(bd) are of order − . a precise prediction for su( )- breaking effects is difficult to obtain. allowing for % su( )-breaking effects in the matrix elements of the four-quark operators describing the spectator con- tributions, we estimate that the resulting contributions to the lifetime ratio are of order – %. contributions of order % (or less) could also arise from su( )- breaking effects in the matrix elements appearing at order /m b in the expansion ( ). hence, we agree with ref. [ ] that τ(bs) τ(bd) = ±o( %) . ( ) . lifetime ratio τ(Λb)/τ(bd) as mentioned in the introduction, the low experimental value of the lifetime ratio τ(Λb)/τ(bd) is the primary motivation for our study. we shall now discuss the structure of spectator contributions to this ratio. it is important that heavy-quark symmetry allows us to reduce the number of hadronic parameters contributing to the decay rate of the Λb baryon from four to two, and that these parameters are almost certainly positive (unless the quark model is completely misleading) and enter the decay rate with the same sign. thus, unlike in the meson case, the structure of the spectator contributions to the width of the Λb baryon is rather simple, and at least the sign of the effects can be predicted reliably. for a more detailed discussion, we distinguish between the two cases where one does or does not allow spectator contributions to enhance the theoretical prediction for the semileptonic branching ratio, bsl, of b mesons. as we will discuss below, the theoretical prediction for bsl, which neglects spectator con- tributions, is slightly larger than the central experimental value. if spectator effects increased the prediction for bsl further, this discrepancy could become uncomfortably large. if we do not allow for an increase in the value of the semileptonic branching ratio, the explanation of the low value of τ(Λb)/τ(bd) must reside entirely in a low value of the Λb lifetime (rather than a large value of the b-meson lifetime). this can be seen by writing τ(Λb) τ(bd) = τ(Λb) ( τ(b−) τ(bd) ) / [τ(b−) τ(bd)] / = τ(Λb) bsl ( τ(b−) τ(bd) ) / Γsl(b) , ( ) where bsl is the average semileptonic branching ratio of b mesons, and Γsl(b) is the semileptonic width. in the second step we have replaced the geometric mean [τ(b−) τ(bd)] / by the average b-meson lifetime, which because of isospin symmetry is correct to order /m b in the heavy-quark expansion. since there are no spectator contributions to the semileptonic rate Γsl(b), and since we do not allow an enhancement of the semileptonic branching ratio, in order to obtain a small value for τ(Λb)/τ(bd) we can increase the width of the Λb baryon and/or decrease (within the experimental errors) the lifetime ratio τ(b−)/τ(bd). allowing for a downward fluctuation of this ratio by two standard deviations, i.e. τ(b−)/τ(bd) > . , and using the estimate of /m b corrections in ( ), we conclude that τ(Λb) τ(bd) > . × [ . − Γspec(Λb) Γ(Λb) ] = . − (d + d b̃) r , ( ) where Γspec(Λb) is the spectator contribution to the width of the Λb baryon. the values of the coefficients di are given in table . if we assume that r and b̃ are of order unity, we find that the spectator contributions yield a reduction of the lifetime of the Λb baryon by a few per cent, and that τ(Λb)/τ(bd) > . , in contrast with the experimental result given in ( ). if, for example, we try to push the theoretical prediction by taking the large value b̃ = . (corresponding to a violation of the valence-quark approximation by %) and choosing a low matching scale µ = mb/ , we have to require that r > rmin with rmin = . , . and . for τ(Λb)/τ(bd) = . , . and . (corresponding to the central experimental value and the σ and σ fluctuations). hence, even if we allow for an upward fluctuation of the experimental result by two standard deviations, we need a value of r that is significantly larger than most quark-model predictions (see the discussion in section . ). clearly, a reliable field-theoretic calculation of the parameters r and b̃ is of great importance to support or rule out such a possibility. table : coefficients di appearing in ( ) and ( ). µ d d d d mb/ . . . − . mb . . . − . mb . . . − . on the other hand, the low experimental value of the semileptonic branching ratio may find its explanation in a low renormalization scale (see section below), or it may be caused by the effects of new physics, such as an enhanced rate for flavour-changing neutral currents of the type b → sg [ ]–[ ]. hence, one may be misled in using the semileptonic branching ratio as a constraint on the size of spectator contributions. then there is the possibility to decrease the value of τ(Λb)/τ(bd) by increasing the lifetime of the bd meson, i.e. in ( ) we can allow for spectator contributions to the width of the bd meson. from table , it follows that the contributions of the parameters b and b are very small (of order − ) and can safely be neglected. thus, we obtain τ(Λb) τ(bd) ' . − (d + d b̃) r − (d ε + d ε ) , ( ) where the coefficients d and d are also shown in table . at first sight, it seems that with a positive ε and a negative ε of order /nc one could gain a contribution of about − . , which would take away much of the discrepancy between theory and experiment. however, the experimental result for the lifetime ratio τ(b−)/τ(bd) imposes a useful constraint. using ( ) to eliminate ε from the relation ( ), and allowing the parameters bi to take values between and , we find τ(Λb) τ(bd) ' . ± . + . ε − (d + d b̃) r > . − (d + d b̃) r . ( ) where in the last step we have assumed that |ε | < . , which we consider to be a very conservative bound. even in this extreme case, a significant contribution must still come from the parameters r and b̃. in view of the above discussion, the short Λb lifetime remains a potential prob- lem for the heavy-quark theory. if the current experimental value persists, there are two possibilities: either some hadronic matrix elements of four-quark opera- tors are significantly larger than naive expectations based on large-nc counting rules and the quark model, or (local) quark–hadron duality, which is assumed in the calculation of lifetimes, fails in non-leptonic inclusive decays. in the sec- ond case, the explanation of the puzzle lies beyond the heavy-quark expansion. let us, therefore, consider the first possibility and give a numerical example for some possible scenarios. assume that µ = mb/ is an appropriate scale to use in the evaluation of the wilson coefficients, and that b̃ = . . then, to obtain τ(Λb)/τ(bd) = . without enhancing the prediction for the semileptonic branch- ing ratio requires r ' , i.e. several times larger than quark-model estimates. if, on the other hand, we consider r = . as the largest conceivable value, we need ε '− . , corresponding to a rather large matrix element of the colour-octet op- erator ts−p. such a value of ε leads to an enhancement of the b-meson lifetime, and hence to an enhancement of the semileptonic branching ratio of b mesons, by ∆bsl ' %. as we will discuss in section , this is still tolerable provided yet unknown higher-order corrections confirm the use of a low renormalization scale. although in both cases some large parameters are needed, we find it important to note that until reliable field-theoretic calculations of the matrix elements of four- quark operators become available, a conventional explanation of the Λb-lifetime puzzle cannot be excluded. . relation with the conventional factorization approach we now discuss in detail the relation of our approach with previous analyses based on the factorization approximation [ ]. this approximation amounts to setting (see appendix a) bi(µhad) = ( αs(mb) αs(µhad) ) /β , εi(µhad) = , ( ) at some hadronic scale µhad � mb. here β is the first coefficient of the β function. the evolution of the operators from mb to µhad is done to leading logarithmic order [ , , ]. for the purpose of our discussion, we fix µhad such that αs(µhad) = . . then the relation between the hadronic parameters renormalized at the scale mb with those renormalized at µhad, as given in (a. ), is: bi(mb) ' . bi(µhad) − . εi(µhad) , εi(mb) ' − . bi(µhad) + . εi(µhad) . ( ) the theoretical prediction for the lifetime ratio τ(b−)/τ(bd) in terms of the hadronic parameters renormalized at the scale µhad is obtained by combining ( ) with the numbers given in table . we find τ(b−) τ(bd) ' + . b (µhad) − . b (µhad) − . ε (µhad) + . ε (µhad) . ( ) the factorization approximation bi(µhad) ' . and εi(µhad) = leads to τ(b−)/τ(bd) ' . , which is close to the value obtained by bigi et al. [ ]. however, it is evident from ( ) that even at a low scale the coefficients of the non-factorizable terms are still much larger than those of the factorizable ones. hence, it remains true that non-factorizable corrections are potentially important. it would be justified to neglect these contributions only if the parameters εi(µhad) were significantly smaller than %. however, to the best of our knowledge there is currently no compelling argument to support such a strong restriction. semileptonic branching ratio of b mesons the semileptonic branching ratio of b mesons has received considerable attention in the past. it is defined as bsl = Γ(b̄ → x eν̄)∑ ` Γ(b̄ → x `ν̄) + Γnl + Γrare , ( ) where Γnl and Γrare are the inclusive rates for non-leptonic and rare decays, respectively. the status of the experimental results on the semileptonic branching ratio is controversial, as there is a discrepancy between low-energy measurements performed at the Υ( s) resonance and high-energy measurements performed at the z resonance. the average value at low energies is bsl = ( . ± . )% [ ], whereas high-energy measurements give b (b) sl = ( . ± . )% [ ]. the superscript (b) indicates that this value refers not to the b meson, but to a mixture of b hadrons (approximately % b−, % b̄d, % bs, and % Λb). assuming that the corresponding semileptonic width Γ (b) sl is close to that of the b meson, we can correct for this and find bsl = (τ(b)/τ(b)) b (b) sl = ( . ± . )%, where τ(b) = ( . ± . ) ps is the average lifetime corresponding to the above mixture of b hadrons [ ]. the discrepancy between the low-energy and high-energy measurements of the semileptonic branching ratio is therefore larger than standard deviations. if we take the average and inflate the error to account for this fact, we obtain bsl = ( . ± . )% . ( ) theoretically, this is expected to be a very good approximation. in understanding this result, an important aspect is charm counting, i.e. the measurement of the average number nc of charm hadrons produced per b decay. theoretically, this quantity is given by nc = + b(b̄ → xcc̄s′) −b(b̄ → no charm) , ( ) where b(b̄ → xcc̄s′) is the branching ratio for decays into final states containing two charm quarks, and b(b̄ → no charm) ∼ . [ , , ] is the standard model branching ratio for charmless decays. recently, two new measurements of the average charm content have been performed. the cleo collaboration has presented the value nc = . ± . [ , ], and the aleph collaboration has reported the result nc = . ± . [ ]. the average is nc = . ± . . ( ) the naive parton model predicts that bsl ' % and nc ' . ; however, it has been known for some time that perturbative corrections could change these results significantly [ ]. with the establishment of the /mq expansion, the non-perturbative corrections to the parton model could be computed, and their effect turned out to be very small. this led bigi et al. to conclude that values bsl < . % cannot be accommodated by theory, thus giving rise to a puzzle referred to as the “baffling semileptonic branching ratio” [ ]. recently, bagan et al. have completed the calculation of the o(αs) corrections including the effects of the charm-quark mass [ ], finding that they lower the value of bsl significantly. the analysis of bagan et al. has been corrected in an erratum [ ]. here we shall present the results of an independent numerical analysis using the same theoretical input. as the subject is of considerable importance, we shall explain our analysis in detail. the semileptonic branching ratio and nc depend on the pole masses of the heavy quarks, which we allow to vary in the range mb = ( . ± . ) gev , mb −mc = ( . ± . ) gev , ( ) corresponding to . < mc/mb < . . here mb is the pole mass defined to one- loop order in perturbation theory. the difference mb −mc is free of renormalon ambiguities and can be determined from spectroscopy (see, e.g., ref. [ ]). bagan et al. have also considered the theoretical predictions in a scheme where the quark masses are renormalized at a scale µ in the ms scheme. we discuss this scheme in appendix b. at order /m b in the heavy-quark expansion, non-perturbative ef- fects are described by the single parameter µ g(b) defined in ( ); the dependence on the parameter µ π(b) is the same for all inclusive decay rates and cancels out in bsl and nc. moreover, the results depend on the scale µ used to renormalize the coupling constant αs(µ) and the wilson coefficients c±(µ) entering the non- leptonic decay rate. they also depend on the value of the qcd scale parameter Λqcd, which we fix taking αs(mz) = . ± . . the corresponding uncer- tainty is smaller than that due to the variation of the mass parameters and is added in quadrature. for the two choices µ = mb and µ = mb/ , we obtain bsl = { . ± . %; µ = mb, . ± . %; µ = mb/ , nc = { . ∓ . ; µ = mb, . ∓ . ; µ = mb/ . ( ) the errors in the two quantities are anticorrelated. notice that the semileptonic branching ratio has a much stronger scale dependence than nc. this is illustrated in figure , where we show the two quantities as a function of µ. by choosing a low renormalization scale, values bsl < . % can easily be accommodated. the experimental data prefer a scale µ/mb ∼ . – . , which is indeed not unnatural. using the blm scale-setting method [ ], luke et al. have estimated that µ ' . mb is an appropriate scale in this case [ ]. mc/mb = . . . . . . . . µ/mb b s l ( % ) mc/mb= . . . . . . . . µ/mb . . . . n c figure : scale dependence of the theoretical predictions for the semileptonic branching ratio and nc. the bands show the average experimental values. the combined theoretical predictions for the semileptonic branching ratio and charm counting are shown in figure . they are compared with the experimental results obtained at the Υ( s) and at the z resonance. it was argued that the combination of a low semileptonic branching ratio and a low value of nc would constitute a potential problem for the standard model [ ]. however, with the new experimental and theoretical numbers, only for the low-energy measurements a small discrepancy remains between theory and experiment. note that, using ( ), our results for nc can be used to obtain predictions for the branching ratio b(b̄ → xcc̄s′), which is accessible to a direct experimental determination. our prediction of ( ± )% for this branching ratio agrees well with the preliminary result of the cleo collaboration: b(b̄ → xcc̄s′) = ( . ± . )% [ ]. having discussed the status of the theoretical predictions obtained to order /m b in the heavy-quark expansion, we now investigate the spectator contribu- tions to the semileptonic branching ratio and nc. this extends, in the context . . . . . . . µ/mb mc/mb le he bsl (%) . . . . n c figure : combined theoretical predictions for the semileptonic branching ra- tio and charm counting as a function of the quark-mass ratio mc/mb and the renormalization scale µ. the data points show the average experimental values for bsl and nc obtained in low-energy (le) and high-energy (he) measure- ments. of the heavy-quark expansion, the phenomenological study presented in ref. [ ]. we consider the average of bsl and nc for b − and bd mesons, and write for the spectator contributions to these quantities ∆bsl,spec = b b + b b + b ε + b ε , ∆nc,spec = n b + n b + n ε + n ε . ( ) the coefficients bi and ni are given in table . if, as previously, we eliminate ε from these equations using the constraint ( ) imposed by the measurement of τ(b−)/τ(bd), and we allow that the parameters bi take values in the range to , we obtain ∆bsl,spec ' (− . ε + . ± . ) % , ∆nc,spec ' ( . ± . ) ∆bsl,spec . ( ) for reasonable value of ε , we expect a contribution to the semileptonic branching ratio of order % or less, and a negligible effect on nc. however, without a detailed calculation of the hadronic parameters we cannot obtain a quantitative prediction of the spectator contributions. nevertheless, we find it interesting that there is at least a potential to change, and in particular to lower, the value of bsl by . – %. to achieve such a decrease requires that the hadronic parameter ε , which parametrizes the matrix element of the colour octet–octet operator t q s−p these are approximately the quantities measured experimentally. however, measurements at lep receive a contamination from bs and b-baryon decays. in ( ), is positive and of order . – . . it will be interesting to see if future calculations of this parameter will confirm or rule out this scenario. table : coefficients bi and ni (in %) appearing in ( ). µ b b b b mb/ . − . − . − . mb . − . − . − . mb . − . − . − . µ n n n n mb/ . − . − . − . mb . − . − . − . mb . − . − . − . conclusions in this paper, we have studied spectator effects in inclusive decays of beauty hadrons. although these effects are suppressed by three powers of Λqcd/mb in the heavy-quark expansion, they cannot be neglected because of the large phase- space factor for two-body scattering. the contributions of spectator effects to inclusive decay rates are given by the hadronic matrix elements of the four local operators in ( ). for mesons, we have expressed these matrix elements in terms of the hadronic parameters b , and ε , defined in ( ). for the Λb baryon, heavy- quark symmetry reduces the number of independent matrix elements from four to two, which we parametrize by r and b̃ as defined in ( ) and ( ). although our parametrization is motivated by commonly made simplifications, such as the vacuum insertion and the valence-quark approximations, we stress that it is intro- duced without any loss of generality. for a complete understanding of spectator effects, it will be necessary to evaluate these parameters non-perturbatively, e.g. in lattice simulations. we find that in predictions for lifetimes and the semileptonic branching ratio of b mesons, the coefficients of the colour octet–octet non-factorizable operators are much larger than those for the colour singlet–singlet factorizable operators. thus the contributions from the non-factorizable operators cannot be neglected, even though their matrix elements are suppressed in the large-nc limit. the ratio τ(b−)/τ(bd) is particularly sensitive to non-factorizable contribu- tions [see ( ) and table ], making it difficult to predict this quantity with a we recall, however, that according to ( ) a positive value of ε increases the theoretical prediction for the lifetime ratio τ(Λb)/τ(bd). precision of better than about %. for example, assuming that the magnitudes of the parameters ε and ε are smaller than . or . , we find that the predic- tions for this lifetime ratio lie in the ranges . – . and . – . , respectively. however, in our opinion, even if the experimental result had been outside these ranges, the most likely explanation would have been that the εi parameters are larger, rather than a failure of the heavy-quark expansion. the experimental measurement of τ(b−)/τ(bd) imposes the constraint ( ) upon the parameters, which allows us to eliminate ε in other relations. on the other hand, within the heavy-quark expansion there is only room for a very small deviation of the ratio τ(bs)/τ(bd) from unity due to su( )-breaking effects. we estimate these effects to be of order %. understanding the low experimental value of the lifetime ratio τ(Λb)/τ(bd) remains a potential problem for the heavy-quark theory. if the current exper- imental value persists, there are two possibilities: either some hadronic matrix elements of four-quark operators are significantly larger than naive expectations based on large-nc counting rules and the quark model, or (local) quark–hadron duality fails in non-leptonic inclusive decays. in the second case, the explana- tion of the puzzle lies beyond the heavy-quark expansion. in the first case, it is most likely that the baryonic parameter r is much larger than most expectations based on quark-model estimates. it will be interesting to see whether future, field-theoretic calculations will yield values of r which are sufficiently large. until such calculations become available, a conventional explanation of the Λb-lifetime puzzle cannot be excluded. finally, we have performed an analysis of the semileptonic branching ratio of the b meson (bsl) and of the average number of charmed particles produced per decay (nc). our results are summarized in figures and . there is a significant dependence on the predictions for the semileptonic branching ratio on the renormalization scale µ, which is a manifestation of our ignorance of higher-order perturbative corrections. the results for nc, on the other hand, are almost independent of µ. this scale dependence weakens considerably the anticorrelation in the theoretically allowed values for bsl and nc observed in ref. [ ]. in our view, given the theoretical uncertainties and the disagreement between the experimental values for the semileptonic branching ratio obtained in low- and high-energy measurements, there is at present no discrepancy between theory and experiment for bsl and nc. we have also studied the contributions of spectator effects for these quantities and find that they are negligible for nc, whereas they can potentially change the prediction for bsl by up to about %. note added: after completing this work we became aware of a paper by i.i. bigi (preprint und-hep- -big , june [hep-ph/ ]), who dis- alternatively, if we assume that the magnitudes of ε (µhad) and ε (µhad) renormalized at a hadronic scale are less than . and . , then, using ( ), we find that the corresponding predictions lie in the ranges . – . and . – . . cusses theoretical predictions for beauty lifetimes, making strong claims concern- ing the theoretical predictions for the lifetime ratio τ(b−)/τ(bd). in view of our discussion in section . , we must disagree with some statements made in this paper. acknowledgements: we thank patricia ball, jon rosner, berthold stech and kolia uraltsev for helpful discussions. c.t.s. acknowledges the particle physics and astronomy research council for its support through the award of a senior fellowship. appendix a: renormalization-group evolution the four-quark operators appearing in the heavy-quark expansion are convention- ally renormalized at the scale µ = mb. however, one may use the renormalization- group to rewrite them in terms of operators renormalized at a scale µ = mb. the renormalization-group evolution is determined by the anomalous dimensions of the four-quark operators in the hqet, where the b quark is treated as static quark [ ]. in the literature, this evolution is sometimes referred to as “hybrid renormalization” [ , , ]. we find that the operators o q v−a and t q v−a, and similarly o q s−p and t q s−p , mix under renormalization. at one-loop order, the mixing within each pair (o,t ) is governed by the anomalous dimension matrix γ̂ = αs π   cf − cf nc nc   , (a. ) which has eigenvalues and nc. here nc is the number of colours, and cf = (n c − )/ nc is the eigenvalue of the quadratic casimir operator in the funda- mental representation. the operators defined at the scale mb can be rewritten in terms of those defined at a scale µ = mb. in leading logarithmic approximation, the result is o(mb) = [ + cf nc (κ− ) ] o(µ) − nc (κ− ) t (µ) , t (mb) = [ + n c (κ− ) ] t (µ) − cf n c (κ− ) o(µ) , (a. ) where κ = ( αs(µ) αs(mb) ) nc/ β , (a. ) and β = nc − nf is the first coefficient of the β-function (nf = is the number of light quark flavours). given the evolution equations (a. ) for the four-quark operators, it is imme- diate to derive the corresponding equations for the hadronic parameters defined in ( ), ( ) and ( ). we obtain: bi(mb) = [ + cf nc (κ− ) ] bi(µ) − nc (κ− ) εi(µ) , εi(mb) = [ + n c (κ− ) ] εi(µ) − cf n c (κ− ) bi(µ) , r(mb) = κr(µ) + nc (κ− ) b̃(µ) r(µ) , b̃(mb) r(mb) = b̃(µ) r(µ) . (a. ) of course, introducing parameters renormalized at a scale µ = mb would simply amount to a reparametrization of the results and as such is not very illuminating. however, the evolution equations are used in section to study the sensitivity of our results to unknown higher-order corrections. as an illustration, we study the evolution from µ = mb down to a typical hadronic scale µhad � mb, which we choose such that αs(µhad) = . (corre- sponding to µhad ∼ . gev). we find bi(mb) ' . bi(µhad) − . εi(µhad) , εi(mb) ' . εi(µhad) − . bi(µhad) , r(mb) ' [ . + . b̃(µhad)] r(µhad) , b̃(mb) ' b̃(µhad) . + . b̃(µhad) , (a. ) indicating that renormalization effects can be quite significant. if one assumes that the matrix elements renormalized at the scale µhad can be estimated using the vacuum insertion hypothesis for mesons and the valence-quark approximation for baryons, then bi(µhad) ' f b(µhad) f b(mb) = κ− / ' . , εi(µhad) ' , b̃(µhad) ' , (a. ) where the factor κ− / in the first equation arises from the anomalous dimension of the axial current in the hqet [ , ]. using (a. ), we then find that the parameters defined at a renormalization scale mb (as used throughout this paper) would be b (mb) = b (mb) ' . , ε (mb) = ε (mb) ' − . , r(mb)/r(µhad) ' . , and b̃(mb) ' . . thus, for mesons the violations of the factorization approximation induced by the evolution from µhad up to mb remain small, i.e. we find bi(mb) ' and εi(mb) ' . we stress, however, that we do not want to suggest that the choice of parameters in (a. ) is actually physical. for mesons, the large-nc counting rules [ , ] imply that the parameters εi are of order /nc, whereas the parameters bi are of order unity. these results are respected by the evolution equations (a. ), which in the large-nc limit take the form bi(mb) = κ∞ bi(µ) + o( /nc) , εi(mb) = εi(µ) − nc (κ∞ − ) bi(µ) + o( /n c ) , (a. ) where κ∞ = [αs(µ)/αs(mb)] / . under a change of the renormalization scale, the parameters εi stay of order /nc, whereas the parameters bi change by a factor of order unity. appendix b: bsl and nc in the ms scheme the semileptonic branching ratio and nc can also be calculated using running quark masses renormalized in the ms scheme rather than pole masses. to compare the results in such a scheme to those presented in our work, we have to relate the ratio of the pole masses to the ratio of the running masses. there is some freedom in how to do this translation. since in the expressions for the (partial) inclusive decay rates radiative corrections are included to order αs(µ) only, it is consistent to work with the one-loop relation mc mb = mc(µ) mb(µ) ( − αs(µ) π ln mc(µ) mb(µ) ) . (b. ) we shall refer to this choice as scheme ms . alternatively, one may prefer to resum the leading and next-to-leading logarithms to this relation, which leads to mc(µ) mb(µ) = mc mb ( αs(mc) αs(mb) )γ / β { − αs(mc) −αs(mb) π ( γ β −γ β β − )} , (b. ) where γ and γ are the one- and two-loop coefficients of the anomalous dimension of the running quark mass, and β and β are the coefficients of the β-function. we shall call this scheme ms ; it has been adopted in the work of bagan et al. [ ]. our results for these two versions of the ms scheme are: bsl(ms ) = { . ± . %; µ = mb, . ± . %; µ = mb/ , nc(ms ) = { . ∓ . ; µ = mb, . ∓ . ; µ = mb/ , (b. ) bsl(ms ) = { . ± . %; µ = mb, . ± . %; µ = mb/ , nc(ms ) = { . ∓ . ; µ = mb, . ∓ . ; µ = mb/ , and the combined predictions for bsl and nc are shown in figure . contrary to the case of the on-shell scheme, the calculations in the ms scheme become unstable for low values of the renormalization scale. for this reason, we only present result for µ ≥ mb/ . the results obtained in the scheme ms are close to those obtained in the on-shell scheme and presented in section . in the scheme ms , on the other hand, we find lower values for bsl and higher values for nc. we note that our results for this scheme do not coincide with the numbers presented in the erratum of ref. [ ]; in particular, we do not find the large values of nc reported there. the numerical differences are mainly due to the fact that bagan et al. use lower values for the charm-quark mass (they use mc = . gev for the central value of the pole mass rather than . gev), and that they multiply each partial decay rate by the numerical factor ( mb mb(µ) ) = + αs(µ) π ( − ln m b µ ) + . . . , (b. ) which we omit since it cancels trivially in the dimensionless quantities bsl and nc. note that, in particular, this factor is responsible for the large apparent scale dependence of the results presented in ref. [ ]. another difference is that we include in the calculation an estimate of the contribution from charmless decays, using bno charm = ( ± )% [ , , ] and Γ b→u sl /Γ b→c sl ' %. this lowers bsl by a factor . and nc by a factor . . le he µ/mb . . . mc/mb . . . bsl (%) . . . . n c figure : combined theoretical predictions for the semileptonic branching ratio and charm counting as a function of the quark-mass ratio mc/mb and the renormalization scale µ. the solid lines refer to the scheme ms , the dashed ones to ms . it may be argued that the apparent large scheme dependence of the results for the semileptonic branching ratio and nc prevent a reliable theoretical predic- tion. however, as we have shown above the main reason is that the numerical value of the quark mass ratio mc/mb can be quite different in different schemes (mc(µ)/mb(µ) ' . mc/mb in the scheme ms , and . mc/mb in ms ). since the dependence of bsl and nc on the quark-mass ratio comes simply from phase space (and is particularly strong for the channel b → cc̄s), we feel that the on- shell scheme is more adequate for performing the calculation. in other words, we expect that in the ms scheme one would encounter larger higher-order corrections, once the calculation is pushed to order α s and higher. references [ ] i.j. kroll, to appear in: proceedings of the th international symposium on lepton photon interactions (lp ), beijing, p.r. china, august . the quoted value of τ(Λb)/τ(bd) includes the new preliminary result of . ± . ± . reported in: g. apollinari (cdf collaboration), presented at the aspen winter conference on particle physics, aspen, colorado, january . 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[ ] a.j. buras, j.m. gérard and r. rückl, nucl. phys. b , ( ). corrigendum: the biological basis of mathematical beauty correction published: september doi: . /fnhum. . frontiers in human neuroscience | www.frontiersin.org september | volume | article edited and reviewed by: mikhail lebedev, duke university, united states *correspondence: semir zeki s.zeki@ucl.ac.uk oliver y. chén yibing.chen@yale.edu specialty section: this article was submitted to cognitive neuroscience, a section of the journal frontiers in human neuroscience received: august accepted: september published: september citation: zeki s, chén oy and romaya jp ( ) corrigendum: the biological basis of mathematical beauty. front. hum. neurosci. : . doi: . /fnhum. . corrigendum: the biological basis of mathematical beauty semir zeki *, oliver y. chén * and john paul romaya laboratory of neurobiology, university college london, london, united kingdom, department of psychology, yale university, new haven, ct, united states keywords: mathematical beauty, biological beauty, artifactual beauty, deductive logic, neuroesthetics a corrigendum on the biological basis of mathematical beauty by zeki, s., chén, o. y., and romaya, j. p. ( ). front. hum. neurosci. : . doi: . /fnhum. . in the original article, there was an error. the square root symbol is missing from our description of the results. a correction has been made to the results section, subsection primary finding, paragraph two: “let rij denote the beauty rating that the i th subject gives to the jth formula; let uij denote individual i’s understanding of the jth formula; let n denote the total number of subjects; let xj : = ∑n i= rij/n and yj : = √ ∑n i= ( rij − xj ) /(n − ) be the mean beauty rating (m-br) and standard deviation of beauty ratings (sd-br), given to the jth formula across subjects, respectively; let µj : = ∑n i= uij/n and σj : = √ ∑n i= ( uij − µj ) /(n − ) be the mean understanding rating of the formula (m-ur) and standard deviation of the understanding rating (sd-ur), given to the jth formula across subjects, respectively.” the authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. the original article has been updated. copyright © zeki, chén and romaya. this is an open-access article distributed under the terms of the creative commons attribution license (cc by). the use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. no use, distribution or reproduction is permitted which does not comply with these terms. https://www.frontiersin.org/journals/human-neuroscience https://www.frontiersin.org/journals/human-neuroscience#editorial-board https://www.frontiersin.org/journals/human-neuroscience#editorial-board https://www.frontiersin.org/journals/human-neuroscience#editorial-board https://www.frontiersin.org/journals/human-neuroscience#editorial-board https://doi.org/ . /fnhum. . http://crossmark.crossref.org/dialog/?doi= . /fnhum. . &domain=pdf&date_stamp= - - https://www.frontiersin.org/journals/human-neuroscience https://www.frontiersin.org https://www.frontiersin.org/journals/human-neuroscience#articles https://creativecommons.org/licenses/by/ . / mailto:s.zeki@ucl.ac.uk mailto:yibing.chen@yale.edu https://doi.org/ . /fnhum. . https://www.frontiersin.org/articles/ . /fnhum. . /full http://loop.frontiersin.org/people/ /overview http://loop.frontiersin.org/people/ /overview https://doi.org/ . /fnhum. . https://doi.org/ . /fnhum. . http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / corrigendum: the biological basis of mathematical beauty none pentaquarks with anticharm or beauty revisited physics letters b ( ) – contents lists available at sciencedirect physics letters b www.elsevier.com/locate/physletb pentaquarks with anticharm or beauty revisited jean-marc richard a, alfredo valcarce b, javier vijande c,∗ a université de lyon, institut de physique nucléaire de lyon, in p -cnrs-ucbl, rue enrico fermi, villeurbanne, france b departamento de física fundamental and iuffym, universidad de salamanca, e- salamanca, spain c unidad mixta de investigación en radiofísica e instrumentación nuclear en medicina (irimed), instituto de investigación sanitaria la fe (iis-la fe), universitat de valencia (uv) and ific (uv-csic), valencia, spain a r t i c l e i n f o a b s t r a c t article history: received august received in revised form january accepted january available online january editor: j.-p. blaizot we use a constituent model to analyze the stability of pentaquark q̄ qqqq configurations with a heavy antiquark c̄ or b̄, and four light quarks uuds, ddsu or ssud. the interplay between chromoelectric and chromomagnetic effects is not favorable, and, as a consequence, no bound state is found below the lowest dissociation threshold. © the author(s). published by elsevier b.v. this is an open access article under the cc by license (http://creativecommons.org/licenses/by/ . /). funded by scoap . . introduction there is a renewed interest in the spectroscopy of exotic hadrons containing one or two heavy constituents. for a review, see, e.g., [ – ]. new configurations are studied, and exotic states suggested in the s or s are revisited. among the first multiquark candidates involving heavy flavors, there is the q̄ qqqq pentaquark proposed independently and simul- taneously by the grenoble group and by harry lipkin [ , ]. the word pentaquark was introduced in this context. for the chromomagnetic interaction, the p q̄ = q̄ qqqq is very similar to the h = uuddss of jaffe [ ], who realized that for a spin j = and color-singlet state, the color-spin operator on = n∑ i< j λ̃i .λ̃ j σ i σ j , ( ) applied to uuddss, reaches its largest eigenvalue o = , to be compared to o = for each spin / baryon of the threshold. this means that in the limit of flavor symmetry su( )f , a chromo- magnetic operator h c m = −a o gives an additional downwards shift δm c m = a = (� − n) ∼ mev , ( ) as compared to the threshold, provided the short-range correlation factor (in simple potential models, it is proportional to the expec- * corresponding author. e-mail addresses: j-m.richard@ipnl.in p .fr (j.-m. richard), valcarce@usal.es (a. valcarce), javier.vijande@uv.es (j. vijande). https://doi.org/ . /j.physletb. . . - /© the author(s). published by elsevier b.v. this is an open access artic scoap . tation value of δ(ri j )) is assumed to be the same for the h as for the ground-state baryons. similarly, an eigenvalue o = is found for a qqqq system in a state of color and spin j q = corresponding to a su( )f triplet of flavor. this means that in the limit where the mass of the heavy quark becomes infinite, i.e., the chromomagnetic en- ergy is restricted to the light sector, a downwards shift δm = a ∼ mev is obtained for q̄ qqqq, as compared to its lowest thresh- old q̄ q + qqq. again, the value δm ∼ mev is derived assuming that the qq short-range correlation is the same in q̄ qqqq as in qqq. this mechanism of chromomagnetic binding was analyzed in several subsequent papers [ – ]. when the su( )f symmetry is broken, the pentaquark is penalized (say for fixed mass m of u and d, and increased mass ms for the strange quark). adopting a finite mass for the heavy quark also goes against the stability of the heavy pentaquark [ , ]. note that the reasoning leading to δm = a for a spin / q̄ qqqq predicts a chromomagnetic binding δm = a/ ∼ mev for the spin / state. hence both spin s = / and s = / states deserve some investigation. in this letter we adopt a generic constituent model, containing chromoelectric and chromomagnetic contributions, tuned to repro- duce the masses of the mesons and baryons entering the various thresholds and study the pentaquark configurations q̄ uuds, q̄ ddsu and q̄ ssdu with q = c or b, for both s = / and s = / , using a powerful variational method. we switch on and off some of the contributions to understand why stability is hardly reached. sometimes, e.g., in [ ], the ordering of the d̄� vs. d̄ s p threshold was not dis- cussed. le under the cc by license (http://creativecommons.org/licenses/by/ . /). funded by https://doi.org/ . /j.physletb. . . http://www.sciencedirect.com/ http://www.elsevier.com/locate/physletb http://creativecommons.org/licenses/by/ . / mailto:j-m.richard@ipnl.in p .fr mailto:valcarce@usal.es mailto:javier.vijande@uv.es https://doi.org/ . /j.physletb. . . http://creativecommons.org/licenses/by/ . / http://crossmark.crossref.org/dialog/?doi= . /j.physletb. . . &domain=pdf j.-m. richard et al. / physics letters b ( ) – the paper is organized as follows. in sec. , we present briefly the model and the variational method. the results are shown in sec. . some further comments are proposed in sec. . model we adopt the so-called al model by semay and silvestre-brac [ ], already used in a number of exploratory studies of multiquark systems, for instance in our recent investigation of the hidden- charm sector c̄cqqq [ ] or doubly-heavy tetraquarks q q q̄q̄ [ ]. it includes a standard coulomb-plus-linear central potential, sup- plemented by a smeared version of the chromomagnetic interac- tion, v (r) = − λ̃i .λ̃ j [ λ r − κ r − � + v s s (r) mi m j σ i .σ j ] , ( ) v s s = π κ′ π / r exp ( − r r ) , r = a ( mi m j mi + m j )−b , where λ = . gev , � = . gev, κ = . , κ′ = . , a = . gevb− , b = . , mu = md = . gev, ms = . gev, mc = . gev and mb = . gev. here, λ̃i .λ̃ j is a color factor, suitably modified for the quark–antiquark pairs. we disregard the small three-body term of this model used in [ ] to fine-tune the baryon masses vs. the meson masses. note that the smearing parameter of the spin–spin term is adapted to the masses involved in the quark–quark or quark–antiquark pairs. it is worth to emphasize that the parameters of the al potential are con- strained in a simultaneous fit of well-established meson states and baryons, with a remarkable agreement with data, as could be seen in table of ref. [ ]. before implementing any constraint of symmetry, a system q̄ q q q q has three possible color components for an overall color singlet, five spin components for a spin s = / , and four for s = / . the configurations with s = / do not support any bound state in the simple chromomagnetic model and thus are not further studied in the present paper. as for color, a singlet q̄ q is associated with a q q q singlet, and a q̄ q octet can be neutral- ized by any of the two q q q octets. three alternative bases can be obtained by replacing q by either q , q or q . in the limit of large m q , attention was focused in the configu- ration q q q q with optimal chromomagnetic attraction. it corre- sponds to a color and spin s = , which is a combination of the state with s = s = and the one with s = s = . for fi- nite m q , the three spin states with s = also contribute, that can match s = / when coupled to s = / . these three latter states with s = allow one to build an overall s = / , as well as the quark state s = . we calculate the binding energy of mesons, baryons and pen- taquarks by means of an expansion on a set of correlated gaus- sians, schematically �α(x , . . .) = n∑ i= γi [ exp(− x̃ . ai . x / ) ± · · · ] , ( ) where the ellipses stand for terms deduced by permutations dic- tated by the symmetries of the system. the subscript α refers to the spin–isospin–color components which are coupled by the interaction ( ). the vector x stands for the set of jacobi coordi- nates describing the relative motion, namely x̃ = {x , . . . , xn− } for a n-body system. the matrices ai are symmetric and definite pos- itive. the weight factors γi and the range matrices ai are tuned by standard techniques to minimize the energy, for an increasing number of terms n , until a reasonable convergence is reached. we table threshold masses for c̄uuds and b̄uuds, and pentaquark theoretical estimate, q. all masses are in gev. d̄ � . b � . j = / d̄ s p . b s p . q . q . d̄∗ � . b∗ � . j = / d̄∗s p . b∗s p . q . q . push our calculation until the difference of introducing a new term is smaller than mev. in principle, the results are independent of the choice of any particular set of the jacobi coordinates for the five-quark problem shown in fig. of ref. [ ]. however, some sets lead to matrices ai which are closer to a diagonal form and thus leads to faster convergence to the lowest eigenvalue. thus, changing the set of jacobi coordinates and the initial values of the parameters entering the matrices ai is a routine consistency check of such variational methods that has been carried in the present study as well as in ref. [ ]. the first concern is whether or not a state is bound below the lowest threshold, say m b , where m is a meson, and b a baryon. an immediate strategy is to detect the ground state energy lower than the threshold energy m + b . if the state is unbound, one observes a slow decrease toward m + b as n increases. it turns out useful to look also at the content of the variational wave function, which comes very close to % in the singlet–singlet channel of color in the m b basis. on the other hand, if a variational state converges to a bound state as n increases, then it includes sizable hidden-color components even for low n . . results . . results for q̄ uuds a calculation of the masses of mesons d(cū), . . . , b s(sb̄) and baryons p(uud), . . . �b(bud) leads to the threshold masses shown in table , which also displays the best -body energy with the re- quired convergence, n = or n = in eq. ( ). no binding is found, as seen from the variational energy remaining above the threshold and from the color-content of the variational wave function, % in the lowest m b channel of the threshold. this negative result survives a number of changes in the model, by modifying some parameters. one of these checks consists in recalculating the threshold and pentaquark energies with the strength of the hyperfine interaction, the parameter κ′ in eq. ( ), artificially increased by a factor f ′, i.e., κ′ → f ′ κ′. as expected from the papers [ , ], stability should be reached for large f ′, when the chromomagnetic interac- tion dominates. stability is reached for f ′ ∼ in the bottom case and f ′ ∼ . in the charm sector, as expected from the /(mq m q ) dependence of the chromomagnetic interaction. this means that the short-range correlation is significantly weakened in the pen- taquark as compared to its value in baryons, and that the config- uration favoring the chromomagnetic binding is not optimal when the chromoelectric and kinetic terms are included. as a further check, one can also play with the central po- tential. for instance, if the coulomb term in ( ) is reduced by a factor of , namely κ → κ/ , and the threshold and pentaquark energies are recalculated, then the pentaquark remains unbound, but the critical factor for forcing binding is slightly reduced, to f ′ ∼ . in the bottom sector. as already noticed in [ ], this indi- cates that there is somewhat a conflict between the chromoelectric and the chromomagnetic contributions: the chromoelectric forces j.-m. richard et al. / physics letters b ( ) – table threshold masses for c̄ssud and b̄ssud, and pentaquark theoretical estimate, q. all masses are in gev. d̄ s � . b s � . j = / d̄ � . b � . q . q . favor some internal configuration that is nearly orthogonal to the one optimizing the chromomagnetic term. . . results for q̄ ssud the calculations described above are now repeated for the pen- taquark with strangeness s = − . the results are shown in table . the same tests as for s = − have been carried out, which con- firm the absence of binding for this kind of modeling, indepen- dently from the details of the tuning of the parameters. the factor f ′ which ensures binding when multiplying the chromomagnetic term, is now about . in the bottom sector, i.e., somewhat smaller than in the case of strangeness s = − [ ], but still indicating that the pentaquark with one heavy antiquark and strangeness s = − is rather far from stability in this class of potential models. . . other flavor configurations some calculations were carried out for the case of hidden strangeness, namely s̄uuds. in this case, the ordering of the thresh- olds are inverted as compared to the values observed in table . for q = s, k � is below ηp, while for q = c, d̄� is above d̄ s p. no bound states were found. as a curiosity, we have run the case of a fictitious charm quark, say c′, of mass gev, i.e., intermediate between the ac- tual charm quark and the strange quark. no fine tuning is done to fix that mass. it is now observed that the thresholds c̄′ u + uds and c̄′s + uud are nearly degenerate. this provides, in principle, the opportunity to gain some attraction by mixing the configu- rations corresponding to each threshold. however, one does not get binding, because the coupling between the two configurations c̄ ′u + uds and c̄ ′s + uud is not strong enough. . outlook various configurations have been studied for the heavy pen- taquark systems q̄ qqqq with q = c or b and qqqq = uuds, ddsu and ssud, and spin s = / or s = / , in the framework of a con- ventional constituent model. no bound state has been obtained, nor any indication for some narrow resonance in the continuum. our results are on the line of the recent experimental findings of the lhcb collaboration [ ]. to perform exploratory studies of systems with more than three-quarks it is of basic importance to work with models that correctly describe the two- and three-quark problems which thresholds are made of. therefore, varying the parameters do not significantly affect our results, as we have checked, because the induced changes in the multiquark and threshold energies are sim- ilar. obviously, a multiquark state contains color configurations that are not present asymptotically in the thresholds and this is the basic ingredient that may drive to a bound state. as already em- phasized in ref. [ ], and shown in figs. or of this reference, there is a strong competition between the color-spin configura- tions favored by the chromoelectric terms and the ones favored by the chromomagnetic terms, and this mismatch spoils the possible binding of pentaquarks with anticharm or beauty. we have explored different possibilities for the mass m q of the heavy quark. increasing the mass of the heavy quark, separates the two thresholds as seen in table when comparing the results for charm and bottom cases. a large m q induces a large chromoelec- tric attraction in the q̄ s pair, but the same attraction is present in the lowest threshold, b s p. on the contrary, a mass m q � gev makes the two thresholds, b� and b s p, nearly degenerate. then, one may expect a favorable mixing. however, there is a conflict be- tween the color-spin configurations favored by the chromoelectric terms and the chromomagnetic ones. for the resonances, our conclusion is based on the content of the variational wavefunctions, which are found to consist mainly of two color-singlets in the channel corresponding to the lowest threshold. for the light pentaquark states and for the hidden-flavor sector q̄ q qqq, the method of real scaling has been used, which is rather demanding in terms of computation [ – ]. certainly, a critical comparison of the different methods of handling resonances is in order. acknowledgements this work has been funded by ministerio de economía, indus- tria y competitividad and eu feder under contract no. fpa - . references [ ] h.-x. chen, w. chen, x. liu, s.-l. zhu, phys. rep. 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[ ] j.-m. richard, a. valcarce, j. vijande, phys. rev. c ( ) , arxiv: . [hep - ph]. [ ] r. aaij, et al., lhcb, phys. rev. d ( ) , arxiv: . [hep - ex]. [ ] e. hiyama, m. kamimura, a. hosaka, h. toki, m. yahiro, phys. lett. b ( ) , arxiv:hep - ph / [hep - ph]. [ ] y. yamaguchi, a. giachino, a. hosaka, e. santopinto, s. takeuchi, m. takizawa, phys. rev. d ( ) . [ ] e. hiyama, a. hosaka, m. oka, j.-m. richard, phys. rev. c ( ) , arxiv: . [nucl - th]. http://refhub.elsevier.com/s - ( ) - /bib e a a s http://refhub.elsevier.com/s - ( ) - /bib e a a s http://refhub.elsevier.com/s - ( ) - /bib a s http://refhub.elsevier.com/s - ( ) - /bib a s http://refhub.elsevier.com/s - ( ) - /bib c a a s http://refhub.elsevier.com/s - ( ) - /bib c a a s http://refhub.elsevier.com/s - ( ) - /bib c a a e s http://refhub.elsevier.com/s - ( ) - /bib c a a e s http://refhub.elsevier.com/s - ( ) - /bib c a a e s http://refhub.elsevier.com/s - ( ) - /bib e f a es http://refhub.elsevier.com/s - ( ) - /bib c b e a bs http://refhub.elsevier.com/s - ( ) - /bib a a s http://refhub.elsevier.com/s - ( ) - /bib a a s http://refhub.elsevier.com/s - ( ) - /bib b c a s http://refhub.elsevier.com/s - ( ) - /bib c b a s http://refhub.elsevier.com/s - ( ) - /bib c e a s http://refhub.elsevier.com/s - ( ) - /bib e a as http://refhub.elsevier.com/s - ( ) - /bib e a as http://refhub.elsevier.com/s - ( ) - /bib d a s http://refhub.elsevier.com/s - ( ) - /bib a e s http://refhub.elsevier.com/s - ( ) - /bib a e s http://refhub.elsevier.com/s - ( ) - /bib a ds http://refhub.elsevier.com/s - ( ) - /bib a ds http://refhub.elsevier.com/s - ( ) - /bib a a a s http://refhub.elsevier.com/s - ( ) - /bib d a s http://refhub.elsevier.com/s - ( ) - /bib d a s http://refhub.elsevier.com/s - ( ) - /bib d a a d es http://refhub.elsevier.com/s - ( ) - /bib d a a d es http://refhub.elsevier.com/s - ( ) - /bib d a b s http://refhub.elsevier.com/s - ( ) - /bib d a b s pentaquarks with anticharm or beauty revisited introduction model results . results for q̄uuds . results for q̄ ssud . other ﬂavor conﬁgurations outlook acknowledgements references o r i g i n a l a r t i c l e aesthetic the benslimane’s artistic model for leg beauty fahd benslimane received: october / accepted: december / published online: april � the author(s) . this article is published with open access at springerlink.com abstract background in , the author started observing legs considered to be attractive. the goal was to have an ideal aesthetic model and compare the disparity between this model and a patient’s reality. this could prove helpful during leg sculpturing to get closer to this ideal. postop- eratively, the result could then be compared to the ideal curves of the model legs and any remaining deviations from the ideal curves could be pointed out and eventually corrected in a second session. the lack of anthropometric studies of legs from the knee to the ankle led the author to select and study attractive legs to find out the common denominators of their beauty. method the study consisted in analyzing the features that make legs look attractive. the legs of models in magazines were scanned and inserted into a powerpoint program. the legs of live models, barbie dolls, and athletes were pho- tographed. artistic drawings by leonardo da vinci were reviewed and greek sculptures studied. sculptures from the national archaeological museum of athens were photo- graphed and included in the powerpoint program. results and conclusion this study shows that the first criterion for beautiful legs is the straightness of the leg column. not a single attractive leg was found to deviate from the vertical, and each was in absolute continuity with the thigh. the second criterion is the similarity of curve distribution and progression from knee to ankle. level of evidence v this journal requires that authors assign a level of evidence to each article. for a full description of these evidence-based medicine ratings, please refer to the table of contents or the online instructions to authors at www.springer.com/ . keywords legs beauty � calves beauty � ankles beauty � models � leonard de vinci � golden ratio � divine proportions introduction over the last years, with the changes in women’s fashion, legs have become an important element of seduction (fig. ). it is remarkable, however, that cosmetic surgery of the legs is rarely the subject of the media. the slow development of cosmetic surgery of the legs and ankles can be attributed to the fear of the frequent com- plications. meanwhile, no workable aesthetic model of the leg is available. indeed, when slimming down of the ankles is consid- ered, liposuction is performed in a circular fashion. the upper limits of the fat compartments to be aspirated are the lower edge of the medial and lateral gastrocnemius muscles [ ]. thus, the volume is reduced medially and laterally without considering any aesthetic ideal: do ankles have the same concavity medially as laterally? do the lower con- cavities of the legs (ankles) extend cephalad in the same fashion medially as laterally? the same question applies for the calves: when enhancing or reducing the volume of the calves, should it be done in a symmetric fashion? is the medial and lateral convexity of the calves symmetric? in this study the author analyzes legs that are considered the most attractive in the western world. legs of models from body part models, inc. (http://www.bodypartmodels.com) based in los angeles are studied as well as legs of models in f. benslimane (&) clinique benslimane, rue ahmed annaciri, palmier , casablanca, morocco e-mail: clinique.benslimane@gmail.com aesth plast surg ( ) : – doi . /s - - - http://www.springer.com/ http://www.bodypartmodels.com ukraine and france. the evaluation of legs’ curves, their shape, and succession shows that there is a common denom- inator among all attractive legs. the golden ratio as applied to the legs in leonardo da vinci’s drawings is discussed. method three groups of models were analyzed: models from dif- ferent ethnic groups, barbie dolls, and athletes. the author also analyzed two groups of artistic models: drawings by leonardo da vinci (the vitruvian man) and greek sculp- tures (photographs taken at the national archeology museum of athens). models, barbie dolls, and athletes a total of photographs of legs found in fashion and health magazines were scanned and inserted into a pow- erpoint program. other photographs were taken of live models in morocco, france, ukraine, hungary, and the us. it was important for the author to include the study of models’ legs considered as an ideal of beauty. the legs of models who work as ‘‘body doubles’’ in the film industry were studied. thus, the legs of marie delage grujicic, a model for a body part models in los angeles (www. bodypartsmodels.com), were examined and photographed (fig. ). all legs were observed from the anteroposterior view, posteroanterior view, oblique view, and lateral view. one of the most important inclusion criteria was to be able to take photographs at the exact horizontal level of the legs, i.e., not from a superior–inferior perspective as we often see in published articles. to this purpose, the models were asked to stand on a black support of -cm height ( in.). the photographs were taken with the camera at the level of the midportion of the legs (between the knee and the ankle), m away from the model. other photo- graphs were taken at the level of the knee to show the entire lower limb. all photographs were taken with a uniform black background. photographs were taken with the feet together and apart. on some of the models, con- vexities and concavities were marked with different color markers (fig. ). the photos were inserted into the powerpoint program. the author analyzed the photos on the anteroposterior and posteroanterior views as well as on the lateral view. the upper limit of the leg was defined as the midpoint of the popliteal fold and the lower limit was the lateral malleolus (fig. ). as we can draw no conclusion from the study of a single group (models), the author included a completely different group in the study: legs of athletes. the legs of the famous brazilian football player ronaldo were also analyzed (fig. ). finally, it was important to analyze the legs of barbie dolls (fig. a, b). indeed, since its introduction in , the fig. with changes in women’s fashion, legs became an important element of seduction fig. importance of studying models’ legs considered as an ideal of beauty. the legs of marie delage grujicic, a model for body parts models, inc., in los angeles, ca (www.bodypartsmodels.com) aesth plast surg ( ) : – http://www.bodypartsmodels.com http://www.bodypartsmodels.com http://www.bodypartsmodels.com barbie doll became for the first time a model for young children, and sometimes even for adults. anthropomorphic analysis of the legs: the mechanical axis of the lower limbs the initial observation consisted in an overview of the legs in order to analyze the axis of the legs and follow its direction. the mechanical axis of the lower limbs is defined as a straight line going through the middle of the knee joint, the femoral head, and the middle of the ankle joint (fig. ). this axis runs from the head of the femoral bone going slightly obliquely downwards and inwards. the mechanical axis deviates only � from the vertical axis (fig. ), which confers an impression of absolute straightness. fig. marking of the convexities and concavities were made on some of the models with different colors fig. the upper limit of the leg was defined as being the midpoint of the popliteal fold and the lower edge as the lateral malleolus fig. the legs of the famous brazilian football player ronaldo were also analyzed fig. a, b importance of studying the legs of barbie dolls. since the barbie doll’s introduction in , dolls stopped being simple toys and became models for young children aesth plast surg ( ) : – results straightness of the leg column the first common denominator of all attractive legs is their straightness (fig. ). attractive legs are straight and in continuity with the thighs. as soon as the leg column departs from the straight axis (genu valgum or genu varum), it deviates from our perception of beauty (fig. ). this is probably one of the reasons why long, straight, and slender legs are considered especially attractive. our sense of aesthetic harmony is intensified by the blending of fra- gility, represented by thinness, and strength, represented by straightness. the straightness of the legs of models who advertise leg stockings and lingerie is notable (fig. ). absolute straightness is fundamental to our perception of attractiveness. this straightness is found on the legs of the barbie doll. it is interesting to note that some barbie dolls are manufactured with extremely thin legs and no curves whatsoever and other barbie dolls are manufactured with more voluminous, smooth, and gentle curves in their legs. however, in both cases, the leg column is absolutely straight and in sharp continuity with the thigh (fig. ). thus, the first goal for the author when performing a leg sculpture is to make the leg column straight, using lipo- suction, microfat grafting, or both (fig. a–c). similarity of curve distribution among attractive legs subjective observation the convex and concave curves were outlined on the legs with different colors on the powerpoint program: red for the convexities and yellow for the concavities (fig. ). this was done on the medial, lateral, posterior, and anterior aspect of the leg. we found that medially the convex curve is short and very pronounced, followed by a long concav- ity. laterally, the convexity is longer and smoother. it is followed by a gentle short concavity that ends at the external malleolus (fig. ). objective scientific analysis: geometry for didactic purposes and to move from a subjective observation to a more scientific analysis, the author called upon geometry. the legs were divided into thirds (fig. ). it was found that all the models have a medial convexity that straddles the upper and middle third (the lower half of the upper third and the upper half of the middle third), fig. the mechanical axis of the lower limbs is defined as a straight line going through the middle of the knee joint, the femoral head, and the middle of the ankle joint fig. the mechanical axis deviates only � from the vertical axis, which confers an impres- sion of absolute straightness aesth plast surg ( ) : – while the lateral convexity stretches along the upper and middle thirds (fig. ). thus, the medial and lateral con- vexities of the legs are fundamentally asymmetric. from the side view, the posterior convexity occupies the upper two thirds of the leg, just like in its lateral aspect. the anterior leg is an almost straight line (fig. ). the second goal when performing a leg sculpture is to reproduce, as much as possible, the delicate asymmetric curves found on models’ legs (fig. a–c). this is done according to the original artistic drawing developed by the author (fig. ). artistic drawings and sculptures leonardo da vinci drawing: the vitruvian man the curves of the legs of the vitruvian man show perfect symmetry between the medial and lateral aspects of the legs! (fig. a, b). legs shaped like this do not exist in contemporary mankind. the legs may have been drawn like this because since there were no means of locomotion in the renaissance era, probably man’s leg muscles were more developed, resulting in such drawing. if this were the case, these curves should be found on sculptures of the pre- renaissance era. sculptures from ancient greece during a visit to the national archaeology museum of athens, the author observed sculptures that depict the ideal human form of those ancient times (figs. , ). some of them were dated back to bc (zeus and poseidon). the shape and distribution of the curves of such ancient legs are exactly the same as those of men and women models today! (fig. ). how does one interpret the drawings of the great leonardo da vinci? pythagoras ( bc) was the first to argue that the principle of all things is the number. the pythagoreans seek in the number the rule capable of limiting reality, to give order and understanding to the universe. leonardo da vinci adhered strongly to the pythagorean ‘‘mathematical-aesthetic vision’’ fig. the first common denominator of all attractive legs is their straightness. attractive legs are straight and in absolute continuity with the thighs. as soon as the leg column departs from the straight axis (genu valgum or genu varum), it deviates from our perception of beauty fig. comparison between a straight, shapeless legs and b bowed legs. as soon as the axis of the legs diverges from the straight axis, it deviates from our perception of beauty fig. the straightness of the legs of models who advertise leg stockings and lingerie is notable aesth plast surg ( ) : – of the universe. ‘‘beauty cannot be scientific till it takes a mathematical expression’’ was among his favorite expres- sions. can we consider that leonardo da vinci ‘‘adapted’’ his drawing of the leg in order to ‘‘make it correspond’’ (get in the mold) to the golden ratio? (fig. a, b). this question will remain unanswered. discussion illouz [ ] described two fat compartments: lateral and medial. he specified that the upper limit of the fat com- partment to be aspirated is the lower edge of the gastrocnemius muscle. the patient should go on tiptoe to determine the lower edge of the muscles. however, per- forming liposuction caudal to the lower edge of the mus- cles, even by a gradient, assumes that the inner and outer edges of the legs and ankles are symmetrical. chamosa [ , ] described the ankle and the distal leg as a rhomboid prism with a major anteroposterior axis, four sides, and four edges. this description is correct and helps in identifying the four fat compartments on the ankle. however, it does not describe the distribution of curves of the legs from knee to ankle. in his trek toward the ‘‘ideal beautiful normal,’’ howard [ ] applied the ‘‘divine proportion,’’ as described by fig. a–c the first goal when performing a leg sculpture is to give straightness to the leg column using either liposuction, microfat grafting, or both fig. the convex and concave curves were outlined with different colors in the powerpoint program: red for convexities and yellow for the concavities. this was done on the medial, lateral, posterior, and anterior aspect of the leg fig. for didactic purposes, the legs are divided into thirds. the medial and lateral convexities of the legs are fundamentally asymmetric. all the models had a medial convexity that straddles the upper and middle third while the lateral convexity stretches along the upper and middle thirds aesth plast surg ( ) : – ricketts [ ], to the lower extremity. however, it was applied only to the medial aspect of the calves in order to determine what he called the medial ‘‘peak.’’ no mention was made to the medial concavity or to the subtle lateral convex–concave curves. the lateral sweep was described as a long, easy curve that should mimic the lateral gas- trocnemius muscle. one should note that the lateral easy curve does not run from the head of the peroneus to the lateral malleolus; the lateral easy convex curve turns into a slight concavity at the lower third to end up on the lateral malleolus. cuenca-gerra et al. [ ] have proposed a model for calf augmentation. they suggested that the two most attractive feature variables are the anteroposterior (ap) and laterolateral (ll) projections. they correctly identified the junction of the upper and middle thirds of the leg as the point of the highest ap and ll projections. they used fibonacci’s numerical sequence to identify the ideal pro- jection of the calf. they stated that in the posterior view, the leg has the shape of an inverted ‘‘pointed gothic arc’’ and that the relationship with the ankle is . : (the divine proportion = phi) (fig. ). this would suggest that the lateral and medial convexities are alike, i.e., symmet- rical. a quick posterior view examination of the leg clearly shows that the medial and the lateral convexities of the legs are fundamentally not symmetrical. the authors also sug- gested that from the lateral perspective, the leg has the fig. from the side view, the posterior convexity entirely occupies the upper two thirds of the leg just like in its lateral aspect. the anterior leg is almost a straight line fig. a–c the second goal when performing a leg sculpture is to reproduce, as much as possible, the delicate asymmetric curves found on models’ legs fig. the original artistic drawing developed by the author aesth plast surg ( ) : – shape of a half-inverted pointed arc with the convexity to the posterior side. once again, examining the leg from the side perspective shows that the convexity in the upper two thirds inverts into a concavity in the lower third (fig. ). finally, the leg used as a model in their study did not have enough convexity in its medial aspect to balance the lateral curve. in my view, the medial upper convexity followed by the lower pronounced concavity is one of the most attrac- tive features that defines leg beauty. most plastic surgeons who studied leg aesthetics refer- ence ricketts’ article ‘‘the biologic significance of the divine proportion and fibonacci series’’ [ ]. however, the fig. a, b the curves of the legs of the vitruvian man show perfect symmetry between the medial and lateral aspect of the legs. a shape like this does not exist on the legs of contemporary man aesth plast surg ( ) : – article focused on facial and dental proportions but no mention was made to the legs. moreover, the drawing used by ricketts does not portray (illustrate) the application of the golden ratio to the lateral aspect of the legs. art historians as well as theorists of the divine numbers agree that the golden ratio is inherent in every work of art considered beautiful. this ratio ultimately describes the absolute and unique beauty. to understand and interpret beauty, one must return to the basics: the pythagoras-pla- tonic heritage contained in the works of euclid [ ]. we are not completely sure if pythagoras practiced geometry! in fact, all of the works attributed to him are apocryphal, though he is considered by some the inventor of greek mathematics [ – ]. this is another myth that may have been perpetuated until the end of the fourth century bc to explain the origins. the pythagoreans formed a heterogeneous group, few of whom actually practiced mathematics, except for one: archytas of tarentum (around – bc). the pythagoreans were especially interested in the philosophy and mysticism of mathematics. in fact, the ‘‘number’’ was for them a fundamental concept that could explain the world as a whole. the expression ‘‘everything is number’’ offers mainly a metaphysic, and the numbers are integers, whole numbers, equal to or [ . respected art historians think that ‘‘it is simply impossible to speak of shared numbers, percentages or averages (the relation between two parts, either quantitative or qualitative) in pythagorean or euclidian theorems’’ [ ]. conclusion it is natural that some plastic surgeons have tried to find in numbers the secret of beauty. thus, the golden ratio has fig. sculpture of zeus depicting the ideal human form of ancient times (photograph taken by the author at the national archeology museum, athens) fig. the leg taken as a model in the study by cuenca guerra et al. [ ] does not have the form of an inverted ‘‘gothic’’ arc as stated in their article (reprinted with permission from [ ]) fig. the shape and distribution of the curves of ancient legs are exactly the same as those of men and women models today (photograph taken by the author at the national archeology museum, athens) aesth plast surg ( ) : – been applied in this quest. however, one should not try at all costs to find mathematical rules to define facial or body beauty. the use of the golden ratio has been deceptive so far. the proof is that no mathematical formula has been universally accepted to define any area of the face or body by the plastic surgery community. how many plastic sur- geons use the golden ratio in their daily practice? that said, when the most ideal and generally admired propor- tions of leg beauty are studied and thoroughly understood, the cosmetic surgeon may better close the gap between the patient’s reality and the ideal aesthetic model found in nature. acknowledgments the author would like to thank omar slaoui, wayne carey and rebecca kavanaugh for their help in the revision of this article. conflict of interest the author declares that he has no conflicts of interest to disclose. open access this article is distributed under the terms of the creative commons attribution license which permits any use, dis- tribution, and reproduction in any medium, provided the original author(s) and the source are credited. references . illouz yg ( ) body sculpting by lipoplasty. churchill liv- ingstone, new york . chamosa m ( ) comprehensive liposuction of lower limbs: basic concept. aesthetic plast surg : . chamosa m ( ) suction lipectomy of the ankle area. plast reconstr surg : – . howard ps ( ) calf augmentation and correction of contour deformities. clin plast surg ( ): – . ricketts rm ( ) the biologic significance of the divine proportion and fibonacci series. am j orthod : – . cuenca-guerra r, daza-flores jl, saad-saad aj ( ) calf implants. aesthetic plast surg : – . neveux m ( ) the golden number: radiograph of a myth. followed by text by huntley he: the divine proportion. paris: sciences du seuil . burkert w ( ) lore and science in ancient pythagoreanism. harvard university press, cambridge ( for the german text) . philip ja ( ) pythagoras and early pythagoreanism. toronto university press, toronto . procissi a ( ) bibliografia matematica delle grecia classica e di altre civilita antiche bolletino di storia delle scienze matema- tiche, vol . la nuova italia, firenze, p aesth plast surg ( ) : – the benslimane’s artistic model for leg beauty abstract background method results and conclusion level of evidence v introduction method models, barbie dolls, and athletes anthropomorphic analysis of the legs: the mechanical axis of the lower limbs results straightness of the leg column similarity of curve distribution among attractive legs subjective observation objective scientific analysis: geometry artistic drawings and sculptures leonardo da vinci drawing: the vitruvian man sculptures from ancient greece discussion conclusion acknowledgments references wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ remobilization of sleeping beauty transposons in the germline of xenopus tropicalis yergeau et al. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / ( november ) research open access remobilization of sleeping beauty transposons in the germline of xenopus tropicalis donald a yergeau , clair m kelley , emin kuliyev , haiqing zhu , michelle r johnson hamlet , amy k sater , dan e wells and paul e mead * abstract background: the sleeping beauty (sb) transposon system has been used for germline transgenesis of the diploid frog, xenopus tropicalis. injecting one-cell embryos with plasmid dna harboring an sb transposon substrate together with mrna encoding the sb transposase enzyme resulted in non-canonical integration of small-order concatemers of the transposon. here, we demonstrate that sb transposons stably integrated into the frog genome are effective substrates for remobilization. results: transgenic frogs that express the sb transposase were bred with sb transposon-harboring animals to yield double-transgenic ‘hopper’ frogs. remobilization events were observed in the progeny of the hopper frogs and were verified by southern blot analysis and cloning of the novel integrations sites. unlike the co-injection method used to generate founder lines, transgenic remobilization resulted in canonical transposition of the sb transposons. the remobilized sb transposons frequently integrated near the site of the donor locus; approximately % re-integrated with mb of the donor locus, a phenomenon known as ‘local hopping’. conclusions: in this study, we demonstrate that sb transposons integrated into the x. tropicalis genome are effective substrates for excision and re-integration, and that the remobilized transposons are transmitted through the germline. this is an important step in the development of large-scale transposon-mediated gene- and enhancer-trap strategies in this highly tractable developmental model system. background amphibian model systems have provided a wealth of information on the molecular mechanisms controlling early vertebrate development. frogs of the xenopus genus are particularly well suited for embryological study as these animals adapt well to captivity and the females can be induced to lay large numbers of eggs throughout the year. the most commonly used amphi- bian model is the south african clawed frog, x. laevis. genetic manipulation of this species is not practical due to the long generation time (> year) and the pseudo- tetraploid nature of the genome. another species of the xenopus genus, x. tropicalis, shares the embryological advantages of its south african cousin and is better sui- ted for genetic studies as it is a true diploid and has a relatively short generation time (approximately months). the potential of applying modern genetics to this classical embryological model system has resulted in the rapid development of genomic tools for x. tropicalis in recent years (reviewed in [ , ]), and the publication of the genome sequence [ ]. our studies have focused on using the class ii dna ‘cut-and-paste’ transposable elements to modify the frog genome for gene- and enhancer-trapping and for inser- tional mutagenesis [ - ]. transposable elements have been used for many years to experimentally modify the genomes of plants and invertebrates and, more recently, have been applied to vertebrate model systems [ , ]. transgenesis with non-autonomous transposable elements offers advantages over other transgenic methodologies. first, transposable elements efficiently integrate into the target genomes. second, as the transposon is excised from the donor plasmid prior to integration, plasmid sequences, which may cause epigenetic silencing [ , ], are not inte- grated at the targeted locus. third, once integrated into the genome, the transposon transgene is an effective * correspondence: paul.mead@stjude.org department of pathology, st jude children’s research hospital, danny thomas place, memphis, tn , usa full list of author information is available at the end of the article yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / © yergeau et al; licensee biomed central ltd. this is an open access article distributed under the terms of the creative commons attribution license (http://creativecommons.org/licenses/by/ . ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. mailto:paul.mead@stjude.org http://creativecommons.org/licenses/by/ . substrate for excision and re-integration (remobilization) following re-expression of the cognate transposase enzyme. the ability to remobilize transposons resident in the genome can be used for a variety of applications, including large-scale transposon ‘hopping’ screens using gene- or enhancer-trap constructs. remobilization of a non-autonomous transposon trans- gene is achieved by expressing the transposase enzyme in the same cell harboring the transposon. this can be achieved by simply injecting fertilized one-cell embryos from the outcross of transposon transgenic animals with mrna encoding the transposase. as development pro- ceeds, the injected mrna is translated by the host cell and catalyzes the excision and re-integration reactions. this approach has been used successfully with the tol transposon system in fish and frogs [ , - ]. another approach is to develop transgenic animals that express the transposase enzyme under the control of tissue speci- fic promoters and to cross these animals with those that harbor a transposon substrate to generate double-trans- genic progeny. this approach has been used very suc- cessfully for somatic remobilization of the sleeping beauty (sb) transposon to identify cancer genes in mice [ , ]. outcross of the transposase enzyme and transpo- son substrate double transgenic animals can result in novel remobilization events in the progeny [ - ]. we, and others, have used a co-injection strategy with the sb [ ] transposon system to generate transgenic xenopus that express fluorescent proteins under the control of ubiquitous or tissue-specific promoters [ , , ]. the integration events generated by this method in the frog are not caused by the simple trans- position of the transposon from the plasmid into the frog genomic dna. analysis of the integration sites indicated that several copies of the transposon, and parts of the flanking plasmid sequence, are introduced at discrete loci as small-order concatemers. this unex- pected non-canonical integration mechanism makes cloning the integration site complicated and time con- suming [ ]. although the integration events generated by the co-injection strategy resulted in non-canonical integration, we next investigated whether sb transpo- sons stably integrated into the x. tropicalis genome are effective substrates for remobilization. using a double- transgenic strategy, we show that sb transposons in the frog genome can be remobilized following re-expression of the sb transposase and that the remobilized integra- tion events occur via canonical transposition. results generation and analysis of transgenic x. tropicalis expressing sb transposase a transgenic x. tropicalis line was engineered to express the sb transposase under the control of a synthetic regulatory element, chicken b-actin promoter coupled with a cytomegalovirus enhancer (caggs [ ]) [ ]. to track the inheritance of the sb transgene, a x. laevis g crystallin-red fluorescent protein (rfp) [ ] reporter was cloned downstream of the caggs-sb transgene in a head-to-head orientation (figure a). the presence of the linked g crystallin-rfp reporter allows screening for the caggs-sb transgene based on the presence of red eyes (figure b). we used the simple linear plas- mid dna injection method described by etkin and pearman to generate the transgenic sb transposase- expressing frogs [ ]. injected embryos were scored for the presence of rfp expression in the lens, and rfp- positive tadpoles ( rfp-positive from injected, . %) were raised to adulthood. a single founder (caggs-sb ;gcrfp m), from a total of five animals outcrossed to date, was identified. outcross of male founder caggs-sb ;gcrfp m with a wild-type female resulted in rfp-positive tadpoles from a total of , offspring ( . %). the non-mendelian inheritance of the transgene indicates that the germline of the caggs-sb ;gcrfp m founder was mosaic for the transgene. subsequent outcross of f animals derived from caggs-sb ;gcrfp m resulted in the expected % of the progeny expressing the dominant lens-specific rfp reporter (in a representative f out- cross there were rfp-positive tadpoles from a total of , . %). southern blot analysis of rfp-positive tadpoles indicated that several copies of the transgene were integrated at a single locus in the founder (figure c). reverse transcriptase (rt)-pcr and western blot analyses were used to verify that sb transposase was expressed in the transgenic line. rt-pcr analysis showed that rfp-positive tadpoles at stage [ ] express mrna encoding the sb transposase enzyme (figure d). as expected, sibling tadpoles that did not express the rfp reporter in the lens were also negative for sb mrna expression. in adults, robust expression of sb transposase was detected in protein lysates pre- pared from testes harvested from rfp-positive male frogs, but not from rfp-negative animals (figure e). sb is also expressed in the liver of the transgenic frogs, but not in the rfp-negative littermates. generation of double-transgenic ‘hopper’ frogs the caggs-sb ;gcrfp m line was outcrossed with sb transposon transgenic animals that express gfp under the control of the caggs promoter (pt bgfp [ ]). double-transgenic f ’hopper’ frogs (ubiquitous gfp and lens-specific rfp) were outcrossed with wild- type frogs and the progeny (f ) were either analyzed for remobilization events or raised and outcrossed (figure ). five independent substrate donor lines were used to generate double-transgenic hopper lines for this study. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of as the methodology for the generation and analysis of the hopper lines is the same for each donor locus, two donor lines (pt bgfp f and m) will be described in detail below. f hoppers the pt bgfp f founder harbors two independently- segregating alleles: a concatemer of three sb transpo- sons integrated at a single locus on scaffold , at base number ( : ) of the jgi x. tropicalis genomic sequence v . assembly, and another allele with a single-copy transposon integration [ ]. thus, the f hopper frogs inherited either one, or both, of the f integration events. southern blot analysis of progeny from fhopper♂ indicated that this double-transgenic hopper had inherited the trimeric concatemer of pt bgfp on scaffold alone. double-transgenic (rfp +/gfp+) progeny (f ) from the outcross of fhop- per♂ were raised and outcrossed, and the resulting progeny (f ) were analyzed for modification of the par- ental pt bgfp locus (figure ). observation of the gfp expression in the hopper out- cross populations indicated that, in most cases, the gfp expression of the progeny was identical to that of the f founder, suggesting that the parental sb transposon locus was intact. in a small number of the outcross pro- geny, we observed markedly different gfp expression in either small populations of cells within the tadpole (fig- ure a, b) or in whole tadpoles (figure a, b; from , gfp-positive tadpoles). we reasoned that the change in gfp expression might result from the modifi- cation of the parental pt bgfp locus in the remobilized progeny. embryos with small subsets of cells with increased gfp intensity likely represent stochastic trans- posase activity in somatic tissues (somatic remobilization (figure a, b)). an organism-wide change in gfp inten- sity (figure a) likely represents modification of the par- ental transposon donor locus during gametogenesis that is passed on to the resulting progeny. remobilization of a transposon from the donor locus to a novel site will likely alter the local epigenetic environment of the transgene, and also subject the re-integrated transposon to the influence of nearby gene regulatory sequences that differ from the parental locus. genomic dna harvested from gfp-positive progeny from double transgenic (pt bgfp f:caggs-sb ; gcrfp) f hopper frogs was analyzed by southern blot. digestion of genomic dna from pt bgfp f tadpoles with bglii resulted in three bands when the blot was hybridized with a gfp probe (figure c). changes in the southern blot hybridization pattern were used to deter- mine whether the parental concatemer had been altered by expression of the sb transposase. analysis of progeny figure generation of a transgenic xenopus tropicalis that expresses sb transposase. (a) schematic of the pcaggs-sb ; gcrfp construct used to develop sb (sb ) transposase-expressing transgenic frogs. the two transgenes were cloned in a tail-to-tail orientation. not to scale. (b) red lens in the right eye of an adult f transgenic frog from outcross of founder caggs-sb ;gcrfp m. the border of the eye is indicated by the dashed white line. (c) southern blot analysis of genomic dna harvested from rfp-positive and control animals indicated integration of multiple copies of the caggs-sb ;gcrfp linear transgene. the dna was digested with bamhi and the blot was probed with a radiolabelled sb cdna probe (see schematic (a)). (d) rt-pcr analysis of sb expression in tadpoles. sb rna was detected in rfp-positive tadpoles (+rfp) but not in rfp-negative (-rfp) progeny from caggs-sb ;gcrfp m. rna from a wild-type tadpole was used as a negative control (st. ). a mock reverse transcription reaction, without added rt, with rna harvested from an rfp-positive tadpole (+rfp(-rt)) was used as a negative control. primers for x. tropicalis a-actin were used as a control for rna recovery. (e) western blot analysis of sb transposase expression in tissues harvested from adult transgenic frogs. a monoclonal antibody to sb was used to demonstrate abundant transposase expression in the testis and liver of rfp-positive adults, but not in the rfp-negative siblings. protein lysates prepared from tadpoles injected with sb mrna at the one-cell stage were prepared at stage (control lane). the blots were stripped and re- probed with a monoclonal antibody that recognizes xenopus a- actin. pcr: polymerase chain reaction; rfp: red fluorescent protein; rt: reverse transcriptase; sb: sleeping beauty. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of from the outcross of f double transgenic hopper frogs with wild-type animals indicated that most of the pro- geny had inherited the unaltered pt bgfp f parental concatemer (figure c; lanes , and ). examples of germline remobilization of the pt bgfp transposon from ‘gfp-bright’ tadpoles (figure a; tadpoles and ) harvested from the outcross of fhopper♂ are shown in figure c (lanes and , dashed arrows). this data indicates that, as predicted, the gfp-bright individuals in the outcross population of the hopper frogs represent tadpoles that have modified the parental transposon donor locus. thus, remobilized animals can be identified in the outcross population by simply observing the tad- poles for changes in gfp intensity. outcross of eleven f hopper double transgenic frogs indicated that the fre- quency of remobilized progeny varied from . % to . % (figure b). the variation in the remobilization activity between individual hopper frogs likely reflects subtle differences in epigenetic modification of the sub- strate and enzyme transgenes in each animal that may alter the activity of the excision and reintegration reactions. analysis of the cloned flanking sequences of the par- ental locus ( : ) from the remobilized tadpoles (figure c; lane and ) showed no sequence change, indicating that the remobilized transposon was excised from within the donor concatemer (data not shown). extension primer tag selection linker mediated-pcr (epts lm-pcr) and standard genomic pcr [ , ] were used to clone the integration sites of the novel bands. the re-integration event from tadpole fhopper♂ - had occurred on the same scaffold as the parental inte- gration site, and thus represented a ‘local hop’ (table and figure ; tadpole fhopper♂ - ). genomic pcr figure breeding strategy to generate double-transgenic hopper frogs. the f hopper frogs were outcrossed with wild-type animals and the progeny was scored for gfp and rfp expression. the gfp-positive/rfp-negative f progeny were either raised to adulthood for outcross or genomic dna was harvested after stage for molecular analyses. gfp: green fluorescent protein; rfp: red fluorescent protein. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of and sequencing was used to verify both the ’- and ’- ends of the novel insertion site. the integration site of the remobilized pt bgfp transposon is at : and is , bp away from the parental locus on chro- mosome (figure b). sequence analysis of the integra- tion site indicated that the remobilization event was catalyzed by a canonical transposition event. that is, the transposon inserted precisely at the predicted boundary of the indirect repeat/direct repeats (ir/drs). further- more, the integrated transposon is flanked by the expected ta dinucleotide target site duplication cata- lyzed by sb transposase [ - ]. thus, unlike the co- injection method used to generate the pt bgfp founder lines that results in unexpected concatemer formation (figure a, [ ]), the remobilization events catalyzed by re-expression of sb transposase are via canonical trans- position (figure b). to date, we have identified remobilization events, based on differences in gfp expression intensity, from , gfp-positive tadpoles from the outcross of f hopper frogs (figure b). south- ern analysis has confirmed excision and re-integration of a sb transposon from the parental locus and yields an apparent remobilization frequency of approximately . %. pre-sorting tadpoles based on gfp intensity may underestimate the total remobilization activity if the re- integration event resulted in gfp expression that was not markedly different from the parental expression. to test this, we outcrossed a double transgenic hopper frog ( fhopper♂ ) and analyzed all of the gfp-positive progeny by southern blot. the fhopper♂ frog inher- ited both of the pt bgfp transposon alleles from the f founder. the progeny from this fhopper♂ out- cross displayed gfp expression patterns and intensities that were indistinguishable from that of the parental alleles (data not shown). from the gfp-positive progeny analyzed by southern blot, we identified four excision-only events and two remobilizations. samples of genomic dna where changes were evident by south- ern blot analysis were used in epts lm-pcr to clone the integration site of the remobilization events. in this experiment, the remobilization frequency was . % (two remobilization events out of gfp-positive tadpoles). these data indicated that the actual remobilization fre- quency may be somewhat higher than that estimated by simple visual inspection of the gfp-positive progeny. the observed rate of excision-only events in this out- cross population was out of , that is, . %. scoring the outcross progeny of hopper frogs for changes in gfp intensity may also overestimate the remobilization frequency, as this method may not distin- guish between remobilization events and excision-only events. we analyzed gfp-bright tadpoles from the outcross of f and m (see below) hopper frogs, by southern blot analysis and by cloning the novel inser- tion sites by epts lm-pcr. only one gfp-bright tad- pole had an excision-only modification of the parental transposon donor locus ( %); gfp-bright tadpoles ( %) had re-integration events that were evident by novel bands on the southern blot and by cloning the figure somatic remobilization of pt bgfp in double transgenic tadpoles. outcross of double transgenic hopper frogs resulted in progeny that inherited both transgenes. in rare instances, we identified double transgenic tadpoles that express intense levels of the gfp transgene reporter in individual cells or in small groups of cells. the change in gfp expression seen in these somatic cells is likely to be due to sporadic remobilization of the pt bgfp transposon and the change in gfp intensity is likely due to the influence of the local chromatin environment at the novel integration site. the region of each tadpole shown (dashed box) is indicated on the cartoon inset. (a) tail of a double transgenic tadpole with a single muscle cell expression intense gfp (arrow). (b) double transgenic tadpole with high-level gfp expression in a subset of cells in the brachial cartilage (arrow). the immobilized tadpole was also photographed using a dsred filter and the two images were overlaid to demonstrate that this animal had inherited the caggs-sb ;gcrfp transgene (rfp expression in the lens is indicated by the white arrowhead). gfp: green fluorescent protein; rfp: red fluorescent protein. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of sequences flanking the canonical re-transposition events. thus, while it is possible to identify excision-only events by changes in gfp expression, the vast majority of gfp- bright progeny represent re-integration events. remobilization of transposons resident in the genome may result in chromosomal rearrangements near the donor locus [ - ]. in mice, germline remobilization of sb transposons from a high-copy number (approximately copies) concatemer resulted in fre- quent alteration of the genomic sequences flanking the transposon donor locus; nine out of nine remobilized pedigrees examined displayed genomic alterations span- ning bp to bp flanking the donor site [ ]. to determine whether sb remobilization in the frog resulted in similar genomic alterations near the donor locus, we examined the sequences flanking the f donor figure excision and re-integration of sb transposons in the progeny of double-transgenic hopper frogs. (a) gfp expression in sibling tadpoles derived from the outcross of an f hopper frog. tadpoles and are significantly brighter than their gfp-positive siblings (tadpoles , and ). tadpole is a gfp-negative tadpole. dorsal view, with anterior facing towards the right. (b) representative data for the outcross population of f hopper frogs. table includes data from breeding four f ( f♂ , f♂ , f♂ and f♀ ) and seven f ( f ♂a, b, c etc.) double-transgenic hoppers with wild-type frogs. the outcross progeny were scored for gfp expression and the gfp-bright progeny were either harvested for integration site analysis or raised to adulthood and outcrossed. a range of apparent remobilization activity from % to . % was observed in individual f hopper frogs, with an average rate of two remobilization events per thousand gfp-positive progeny ( . %). (c) southern blot analysis of genomic dna harvested from the progeny of double transgenic f hopper frogs. genomic dna was digested with bglii and the blot was probed with a radiolabelled gfp cdna probe. dna harvested from tadpoles in lanes , and have the same banding pattern as the parental pt bgfp f founder line. lanes and show example of remobilization of an sb transposon. the dashed arrow indicates the change in the mobility of the transposon-harboring bglii fragment. lane contains dna from gfp-negative siblings. gfp: green fluorescent protein; sb: sleeping beauty. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of locus by pcr. genomic dna samples from eight remo- bilization events and eight excision-only events were used to amplify the sequences flanking the ’ and ’ ends of the f concatemer on chromosome . in each case, genomic pcr using primers that amplify the ’ and ’ junctions of the f locus generated the appropri- ate sized products (data not shown), indicating that the sequences directly flanking the donor locus are intact following excision of pt bgfp transposons from the donor site. sequence analysis of the re-integration target sites indicated a similar base distribution flanking the canoni- cal ta dinucleotide to that observed with sb integration in mammalian genomes [ , ] (figure d). transpo- sons of the tc /mariner family, including sb, integrate at ta dinucleotides. the consensus sequence for sb integration in frogs, as in mammals, is a palindromic atatatat sequence, where the canonical ta target is in bold, although none of the re-integration events observed in the frog have this exact palindrome. cloning the integration sites of the novel loci indi- cated that the remobilized transposons frequently inte- grate near the parental locus (figures and ; out of classed as local hopping, %). in two cases, we iden- tified remobilization events that had re-integrated within the parental transposon concatemer on scaffold (table and figure a). the scaffold identity was used to ‘map’ the chromosomal location [ ] of the novel integration events and showed that, while local hopping was more frequent, re-integration on other chromo- somes was also detected (figure b; three out of fifteen ( %) of integrations are on different chromosomes). gfp-bright progeny from the outcross of f hopper frogs were raised to the adult stage, and outcrossed to demonstrate that the remobilized transposon alleles are stably transmitted through the germline. genomic dna was harvested from gfp-positive and gfp-negative sib- lings and used for southern blot analysis and for cloning the novel integration site by epts lm-pcr. for exam- ple, remobilized female frog e produced gfp-bright progeny and integration site analysis showed a single copy of the pt bgfp transposon on scaffold ( : ). the novel re-integration event was on the same chromosome as the donor locus (chromosome , linkage group ), approximately cm from the paren- tal f concatemer, and represents a local hop (data not shown). the e integration event was in the ’ utr of a muscle-related coiled coil protein (genbank acces- sion number xm_ . ) gene. m hoppers the pt bgfp m founder had a concatemer of to pt bgfp transposons at a single locus within a repeat on scaffold (linkage group , chromosome ), and mapped, by fluorescence in situ hybridization (fish) analysis, near a telomere on chromosome (figure ). table integration site analysis for remobilized progeny from f hoppers. tadpole right indirect repeat/direct repeats flanking sequence integration site ’ flanking gene ’ flanking gene parental f gcaacgctagtcac...cagttattgatta : psst c orf -like f♂ - gcgcaatactattatacagttgaagtcgg : psst c orf -like f♂ - cgggccatgatgtatacagttgaagtcgg pt bgfpb psst c orf -like f♀ - gtggagctctgaaatacagttgaagtcgg pt bgfpb psst c orf -like f♂ - aaaggcaacacgcgtacagttgaagtcgg : psst c orf -like f♂ - gaatctctgtgatctacagttgaagtcgg : psst c orf -like f♂c- cagagctagatatatacagttgaagtcgg : c orf -like c orf -like f ♀f- tggaaatgcctatatacagttgaagtcgg : c orf -like ikaros f ♂c- aagaaagcacttggtacagttgaagtcgg : dopa decarboxylase dopa decarboxylase f♀ - cccccttcggtgattacagttgaagtcgg : grb cordon-bleu f ♂a- acaaacgggccatgtacagttgaagtcgg : grb cordon-bleu f♂ - tatctaaacaaagttacagttgaagtcgg : cam-pde c cam-pde c tcactacatatttctacagttgaagtcgg : ptprm ptprm f♂ - taagaattaatagttacagttgaagtcgg : c-fyn c-fyn f ♂c- tataaataaagatatacagttgaagtcgg : connexin . c orf -like f♂b- aaggcagtcagttatacagttgaagtcgg : rdc- cop f ♂a- gataactcttaagttacagttgaagtcgg : amphiphysin amphiphysin sequences flanking the novel transposon insertion site were cloned using extension primer tag selection linker mediated-pcr. the remobilization events are mediated by canonical transposition reactions and the transposon sequence (italics) is flanked by the characteristic ta dinucleotide target site duplication (bold). the flanking sequence (depicted in capital letters) was used to interrogate the x. tropicalis genome sequence database (joint genome institute x. tropicalis genome sequence assembly v . ; [ ]) to assign the integration sites to the genomic sequence scaffolds. the genes flanking the novel integration site are listed. athe parental integration site on scaffold was mediated by a non-canonical mechanism. btwo remobilization events showed reintegration of the excised transposon into the donor concatamer locus on scaffold . yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of http://www.ncbi.nih.gov/entrez/query.fcgi?db=nucleotide&cmd=search&term=xm_ . double transgenic m hopper frogs were generated by breeding heterozygous pt bgfp m f frogs with het- erozygous caggs-sb ;gcrfp m f frogs, and the progeny were sorted for gfp-positive and rfp-positive expression. the double-heterozygous m hopper frogs were outcrossed with wild-type animals and remobiliza- tion events were scored in the progeny by observing the outcross population for changes in gfp expression. to date, ten m hoppers have been outcrossed and remobilized (gfp-bright) tadpoles have been identified from , gfp-positive progeny (figure a). genomic dna from several gfp-bright tadpoles was analyzed by southern blot, and this data verified that the banding pattern had changed from the parental m pattern, indi- cative of transposon remobilization. the novel integra- tion sites were cloned (table ), and sequence analysis confirmed that the remobilized transposons had re-inte- grated via canonical sb-mediated transposition (data not shown). the average apparent rate of remobilization was approximately %, and is five-times higher than that observed for the f hopper animals. the higher rate of remobilization observed in the m hoppers compared to the f hoppers may be due to the increased number of potential substrate transposons in the donor concatemer (three for f compared with to for m). a range of remobilization activities, from % to %, was noted between the different m hopper frogs. the m hoppers were produced by breeding frogs that were heterozygous for the sb enzyme transgene with frogs that were het- erozygous for the pt bgfp m allele. double-heterozy- gous males ( mhopper♂ , mhopper♂ , mhopper♂ , mhopper♂ , mhopper♂ , mhopper♂ ) produced offspring with an average remobilization frequency of approximately . %. the frequency of gfp-positive progeny in the outcrosses from these males was approximately %, as expected for the mendelian inheritance of a heterozygous dominant allele. two m hopper male frogs ( mhopper♂ and mhopper♂ ) produced a much higher rate of remobilized (gfp- bright) tadpoles than their siblings (approximately . % figure integration site analysis of remobilized sb transposons. (a) schematic representation of the f donor locus showing the predicted orientation of the trimeric concatemer in scaffold . this injection-mediated integration event occurred by a non-canonical mechanism. (not to scale.) (b) schematic representation of the novel integration event in the remobilized tadpole shown in figure b. epts lm-pcr was used to clone the sequence flanking the ’ end of the pt bgfp transposon and the ’ and ’ flanking sequences were verified using pcr primers designed to the scaffold sequence. the novel integration event occurred on the same scaffold ( at position bp) of the joint genome institute x. tropicalis genome sequence assembly v . as the f transposon donor locus ( : ) and represented a local hop. the sequence of the sb transposon and genomic dna junctions (arrows) indicated that the remobilization event occurred via a canonical transposition reaction. the pt bgfp transposon is flanked by the expected ta dinucleotide target site duplication (tsd; bold underlined), and the transposon is inserted precisely, without any flanking plasmid sequence from the donor site. the genomic dna sequence of scaffold is capitalized and the transposon sequence is in lowercase italics. (not to scale.) (c) the preferred sequence for sb transposon re-integration in the x. tropicalis genome. weblogo analysis http://weblogo.berkeley.edu for the five base pair sequence flanking the ta target site. the relative size of the letters indicates the strength of the information on the y-axis, with the maximum indicated by two bits. the table shows the base distribution of the pt bgfp transposon re-integration target sites. epts lm-pcr: extension primer tag selection linker-mediated polymerase chain reaction; pcr: polymerase chain reaction; sb: sleeping beauty. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of http://weblogo.berkeley.edu compared with . % for male sibling hoppers). intrigu- ingly, these animals appear to be homozygous for both the enzyme (caggs-sb ;gcrfp) and substrate (pt bgfp) transgenes; % of the outcross progeny were rfp-positive and nearly all (> %) were also gfp- positive. southern blot analysis of the outcross progeny indicated that all of the gfp-positive animals (n = for mhopper♂ ; n = for mhopper♂ ) had inherited the m concatemer, and the banding pattern was identical to the parental locus. the gfp-bright tad- poles in the outcross populations of mhopper♂ and mhopper♂ showed changes in parental m locus indicative of excision and re-integration of a transposon from the substrate donor locus. the rare (< %) gfp- negative tadpoles observed in the outcross populations did not inherit the pt bgfp transgene as determined figure schematic representation of remobilized sb transposons in the x. tropicalis genome. (a) local hopping on x. tropicalis chromosome depicts the integration sites for eight local (< kb) remobilization events (hops). (not to scale.) this region of x. tropicalis chromosome is syntenic with human chromosome . the vista http://genome.lbl.gov/vista alignment shows regions of homology between the frog and human genomic sequences; pink represents non-coding regions and blue represents conserved exons. the position of the f donor concatemer is indicated by the grey box. the remobilized transposition events are depicted by the grey triangles. the position and orientation of predicted genes near the f locus are depicted in the lower section of the panel. (b) schematic representation of the x. tropicalis chromosomes indicating the distribution of remobilized sb transposons. the parental f donor site is on chromosome (thick line). the predicted loci of the remobilized transposons are depicted by the thin black lines. approximately % of the remobilization events occur near the donor locus (local hopping), and the remaining % are distributed randomly throughout the genome. sb: sleeping beauty. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of http://genome.lbl.gov/vista by southern blot and genomic pcr for gfp sequences (data not shown). the unexpected non-mendelian inheritance of hoppers m♂ and m♂ is unex- plained; however, this data suggests that increasing the copy number of the transposon substrates in the hopper lines may increase the remobilization frequency observed in the outcross population. to date, four m female hopper frogs have been out- crossed, and the mean remobilization rate from these animals is . %. this may reflect individual differences in excision and reintegration activities between different hopper animals, or it may indicate that remobilization, driven by the caggs-sb transgene, is more efficient in the female germline (mean . %; n = ) than in the male germline (mean . %; n = , unpaired student’s t- test, p = . , degrees of freedom, ). with the f hoppers, we observed a modest increase in the mean remobilization efficiency with the female hoppers ( . %; n = ) compared to the male hoppers ( . %; n = ); however, due to the small sample size, this may not be statistically significant (student’s t-test p = . , degrees of freedom, ). the m pt bgfp concatemer is located on scaffold that maps to chromosome (figure b and c). genomic dna harvested from representative gfp- bright tadpoles from the m hopper outcrosses was ana- lyzed by southern blot and the novel integration sites were cloned by epts lm-pcr. as noted for the remo- bilized f hopper progeny above, the novel integration events from the m hoppers were canonical sb- mediated transposition events. as determined for the remobilization events from the f hopper frogs, a strong bias for local re-integration was observed for the m hoppers; re-integration events on the same scaffold (scaffold ) as the transposon donor were cloned from the gfp-bright tadpoles. discussion sb transposons can be remobilized in x. tropicalis here, we demonstrate that sb transposons integrated into the frog genome are effective substrates for remobi- lization following re-expression of the sb transposase. unlike the integration events observed in the co-injec- tion strategy that were mediated by a complex non- canonical mechanism, the remobilized sb transposons re-integrated via canonical sb-mediated transposition. the observed frequency of excision and subsequent re- integration of the parental pt bgfp transposon was low (on average, less than %). our data in x. tropicalis is similar to that observed in other in vitro [ ] and in vivo [ , , ] systems, where low-copy number trans- poson donor sites served poorly as substrates for remo- bilization. in mammals, increasing the number of transposon substrates by using donor sites that contain high-order concatemers resulted in increased remobili- zation activity [ , ]. for example, in ab embryonic stem cells, a single sb transposon was ‘knocked in’ to the hprt gene on the mouse x chromosome and subse- quent transient expression of sb transposase (sb ) resulted in a transposition rate of circa . × - events per cell per generation [ ]. in mice, low-copy number sb transposon donor sites result in a low frequency of remobilization events that are passed through the germ- line [ , ]. for example, single-copy sb transposon donors result in novel re-integration sites in approxi- mately one embryo in every one hundred (around %) in an outcross of double transgenic ‘seed’ mice [ ]. increasing the number of transposon substrates by using donor sites that contain high-order concatemers resulted in increased remobilization activity; however, geurts and colleagues noted that there was not a linear correlation between donor site copy number and remo- bilization activity [ ]. this suggests that other factors, such as the methylation status, and other local chroma- tin-environment factors, may also influence the ability of integrated sb transposons to serve as substrates for remobilization. horie and colleagues observed that low- copy number sb transposon concatemers served very poorly as substrates for remobilization in mice, and that the presence of more copies of the sb transposon in the concatemer acted synergistically to increase the fre- quency of excision and re-integration. with a donor site that contained around copies of the transposon sub- strate, a remobilization rate of . transpositions per genome per animal ( %) was observed [ ]. keng and colleagues also reported a similar transposition fre- quency when using double transgenic mice that con- tained either copies ( . transpositions per gfp- positive mouse) or copies ( . transpositions per gfp-positive mouse) of the substrate transposon in the donor concatemer [ ]. in this study, we used low-copy number donor sites as substrates for remobilization as the integration events observed with the plasmid-mrna co-injection strategy were mediated by a complex, non-canonical integration mechanism [ ]. we reasoned that, if a similar non-cano- nical mechanism were used in the remobilization step, starting with a simple substrate would help facilitate cloning of the remobilization event. although the remo- bilization frequency observed in the outcross of the dou- ble transgenic frogs is low, the re-integration events are canonical sb-mediated transpositions. there are several strategies available to increase the frequency of remobili- zation events in the frog genome. increasing the copy number of sb transposon substrates will likely signifi- cantly increase the frequency of novel re-integration events in the outcross progeny from hopper frogs. transgenic frogs with multiple copies of the pt bgfp yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of figure transposon hopping from the m donor locus. (a) the outcross progeny from nine m hopper adults were scored for changes in gfp intensity indicative of transposon remobilization. the m donor locus contains a concatemer of approximately eight to ten pt bgfp transposons on chromosome . the remobilization frequency is expressed as a percentage of gfp bright tadpoles observed in the gfp-positive outcross population. m hopper frogs m♂ and m♂ are ‘functionally homozygous’ for both the transposon substrate allele and the transposase enzyme transgene (see text for details), and display higher remobilization activity (approximately . %) than their ‘heterozygous’ male hopper littermates ( m♂ , m♂ , m♂ , m♂ , m♂ , m♂ ; approximately . %). outcross of m hopper m♀ produced a remobilization rate of > %. (b) schematic representation of the x. tropicalis chromosomes indicating the distribution of remobilized sb transposons. the parental m donor site (thick line) is located on scaffold which maps to chromosome . remobilization of discrete transposons away from the m donor locus is represented by the grey arrows. (not to scale.) (c) fluorescence in situ hybridization of metaphase chromosomes verifies that the m parental donor locus is located near a telomere of x. tropicalis chromosome . gfp: green fluorescence protein; sb: sleeping beauty. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of transposon have been generated ( m and ♀ e) that each harbor more than seven copies of the pt bgfp transposon [ ]. the total number of transposon sub- strates in each hopper line can be further increased by incrossing the hopper lines with other pt bgfp foun- ders that contain multiple copies of the sb transposon. in addition to donor site transposon copy number, the transgenic transposase enzyme may also influence the remobilization activity in the frog. the transgenic sb enzyme frog described here was generated using the first generation sb transposase (sb ; [ ]). in recent years, several hyperactive mutant forms of the sb enzyme have been developed, including sb that has approximately three-fold higher activity [ ] and sb x that has a -fold increase in enzymatic activ- ity when compared to sb [ ]. in addition to the choice of modified enzyme, different promoters with varying transcriptional activity could be used to drive expression of the sb transgene to enhance the rate of germline remobilization. this may not be as simple as finding the most powerful promoter and/or enhancer available, as sb is sensitive to overproduction inhibition, where increasing levels of enzyme impair the overall transposition efficiency [ ]. why are different integration mechanisms observed with the co-injection and the double transgenic strategies? there are several possible reasons for the different inte- gration mechanisms used in the two sb-mediated meth- ods, that is, injection-mediated and breeding-mediated transposition. first, the concentration of the substrate is vastly higher in the injection method where approxi- mately pg (around . × copies) of the plasmid harboring the sb transposon substrate was co-injected with sb mrna. by comparison, the pt bgfp f foun- der used in the transgenic remobilization strategy con- tained three copies of the sb transposon. the sb transposase catalyzes transposition as a dimer of dimers (tetramer) bound to the indirect ir/dr elements that flank the transposon [ ]. the massive excess of sub- strate present in the injection-mediated strategy may prohibit the correct assembly of transposase on the sub- strate and may result in non-canonical enzymatic activ- ity. also, the integrated transposon may also be a better substrate for sb activity due to dna methylation and heterochromatinization [ , ]. recent studies have shown that cpg methylation and supercoiling of sb transposon-harboring plasmids result in highly efficient transposition by the co-injection method in mammals when compared to non-methylated linear plasmid dna donors [ ]. finally, the differences in the integration mechanisms observed with the two strategies may reflect differences in the availability of host factors for sb transposition in the developing gametes and the early-cleavage stage xenopus embryos. potential uses for sb remobilization in x. tropicalis the demonstration that sb transposons stably integrated into the frog genome are effective substrates for remobi- lization is an important step in the development of large-scale insertional mutagenesis and enhancer- or gene-trap screens in the frog. the breeding-based remo- bilization strategy described here provides a simple and robust method for generating novel transgenic lines without the need for labor- and skill-intensive micro- injection methodologies. the frog provides several important advantages for transposon-based genetic screens. first, each outcross can generate several thou- sand progeny. the high fecundity of x. tropicalis indi- cates that, even if the remobilization frequency is low, multiple novel re-integration events can be identified in a single outcross. a second advantage is that xenopus have a long life- span in captivity that may reach two decades or more, and the animals remain fertile for more than ten years. this has important implications for remobilization stra- tegies, as double transgenic hopper frogs can be main- tained and outcrossed at regular intervals for many table integration site analysis for remobilized progeny from m hoppers tadpole right ir/dr flanking sequence integration site ’ flanking gene ’ flanking gene parental m tgttagttattacttacagttgaagtcgg : edem phf e - tcattatcagtatatacagttgaagtcgg : emilin emilin - gctactcacacagttacagttgaagtcgg : spry ndfip - m tgttactgggcacttacagttgaagtcgg : mynn mds a a- agtgtgtagctatatacagttgaagtcgg : gbp gbp c ab- cgggccatgatgtatacagttgaagtcgg repeat - - e f - gcacataatacacatacagttgaagtcgg unknown - - e - catgtacagttgaagtcgg unknown - - sequences flanking seven novel transposon insertion sites from m hoppers were cloned using extension primer tag selection linker mediated-pcr. the transposon sequence (italics) is flanked by the characteristic ta dinucleotide target site duplication (bold). the flanking sequence (depicted in capital letters) was used to interrogate the x. tropicalis genome sequence database (joint genome institute x. tropicalis genome sequence assembly v . ; [ ]) to assign the integration sites to the genomic sequence scaffolds. the genes flanking the novel integration site are indicated. yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of years; male frogs can be outcrossed every two weeks and females every two months. laboratories with limited animal holding space can, with a small cadre of hopper frogs, perform large-scale enhancer- or gene-trap screens, keeping only those tadpoles with interesting gfp expression profiles. the long lifespan of the hopper frogs may also have important implications if epigenetic silencing of the transgenic transposase locus is identified over a series of generations. stably integrated transgenes are frequently subjected to epigenetic silencing over suc- cessive generations [ , , ]. silencing of the transpo- sase locus would likely result in abolishment of the hopping activity. as each generation of frog lives for many years, having to regenerate new lines for hopping strategies is not likely to be a problem in this species. the propensity of sb to catalyze local hopping events is a third advantage that can be exploited to generate insertional mutants of genes near the donor locus. in mice, approximately % of remobilized sb transposons re-integrate within mb of the donor locus [ ]. our data with remobilization of the f locus indicates that local hopping is also a feature of the sb transposition in x. tropicalis. transgenic sb transposon frogs that have integrations in gene-dense regions of the genome can be used as donors for insertional mutagenesis strategies, as re-integration within a nearby gene may disrupt the nor- mal activity of that locus. in the example presented here, the f transposon donor is located on scaffold , which maps to x. tropicalis chromosome and is synte- nic with human chromosome (figure a). it is in a gene dense region with approximately genes in the mb flanking the transposon donor. the genome size of x. tropicalis is approximately one-half that of the human genome [ ], while the gene content of the frog is similar to that of man. thus, the overall gene density is relatively high in the frog. different dna ‘cut and paste’ transposon systems offer unique advantages for manipu- lating the vertebrate genome. for example, the local hopping activity of sb can be exploited to saturate the genomic sequences flanking the transposon donor locus with novel re-integration events. we have recently demonstrated that tol transposons stably integrated into the frog genome are effective substrates for remobi- lization [ ]. the local hopping activity of tol is less pronounced than that of sb; approximately % of tol re-integration events occur near the donor locus, com- pared to approximately % for sb. using nested trans- poson substrates, with, for example, an sb transposon cloned within a tol element, genome-wide remobiliza- tion screens could be performed using tol to randomly distribute the dual substrate throughout the genome, with subsequent sb remobilization to locally saturate regions of interest with novel insertion events. in the study described here, we have used a simple ubiquitous promoter element to drive expression of the gfp repor- ter. substrate transposons that harbor potentially more mutagenic elements, such as polyadenylation trap ele- ments [ ], can be used to efficiently disrupt the activity of the ‘trapped’ gene. finally, the frog is an excellent model for embryologi- cal and biochemical studies due to its small size, simple husbandry and the ease of manipulating embryos at all stages of development. furthermore, as a tetrapod spe- cies, x. tropicalis shares a similar body plan with mam- mals, allowing analysis of developmental processes that are unique to higher vertebrates, such as limb and digit pattern formation. combining these features with a sim- ple and robust method for generating novel transgenic lines will provide valuable tools to apply to this highly tractable developmental model system. conclusions sb transposons stably integrated into the x. tropicalis genome are substrates for remobilization co-injection of plasmid dna harboring a sb transposon together with mrna encoding the sb transposase results in efficient transgenesis of x. tropicalis. the inte- gration events mediated by this co-injection approach are complex and frequently contain low-order concate- mers of the transposon. in this study, we demonstrate that sb transposons stably integrated in the frog genome are effective substrates for remobilization. transgenic frogs that express sb transposase in the germline were bred with sb transposon frogs and the double transgenic progeny were outcrossed to wild-type ani- mals. remobilization events were readily identified by increased gfp expression in the offspring where the parental transposon concatemer had been modified by the sb enzyme. integration site analysis of the gfp- bright progeny indicated that the transposon re-integra- tion events had occurred via a canonical cut and paste mechanism. the rate of remobilization observed in the frog was similar to that observed in other species when a low copy number concatemer was used as the trans- poson donor. sb transposon remobilization as a tool for genetic manipulation of x. tropicalis the diploid frog x. tropicalis offers several advantages for large-scale forward genetic screens in a tetrapod model, including vast numbers of progeny per spawn, long lifespan and availability of genomic resources including the genome sequence and genetic map. here, we have demonstrated that we can exploit the cut and paste activity of sb transposase to generate novel trans- poson transgenics by simply breeding the double-trans- genic hopper frogs. novel transposon lines are readily identified by changes in gfp reporter expression in the yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of remobilized progeny compared to the parental gfp pat- tern. the local hopping activity of sb can be exploited to saturate genomic regions that flank the transposon donor sites. the ability to generate thousands of pro- geny in each outcross, combined with the ease of identi- fying novel insertion events, will allow large-scale sb- mediated screens to be performed in x. tropicalis. methods plasmids and generation of transgenic lines the generation of the pt bgfp construct and the transgenic pt bgfp x. tropicalis line f have been described previously [ ]. the pcaggs-sb construct was a gift from dr david largaespada [ ]. a , bp hincii/bamhi fragment containing the promoter/ enhancer and the sb transposase from pcaggs-sb was cloned in pbluescript sk+ (pbs-sk+) to generate pbs-caggs-sb . the . kb x. laevis g crystallin promoter driving dsred construct was a gift from dr robert grainger ( . g crystallin-rfp; [ ]). an approximately . kb g -crystallin promoter-rfp frag- ment was pcr amplified from . g crystallin-rfp using primers dsr ’-gtaagcggcagggtcgga- ’ and dsr ’-gcctcgagcgatttcggcc- tattggt- ’, cloned into pgem-teasy (promega, madison, wi, usa), and fully sequenced, to yield pgem-gcrfp. an approximately . kb saci restriction fragment from pgem-gcrfp encoding the g crystallin- rfp reporter was cloned into the unique saci restriction site of pbs-caggs-sb . a single clone was selected with the two mini-genes oriented tail-to-tail in the pbs- sk plasmid (pcaggs-sb ;gcrfp; figure a). the pcaggs-sb ;gcrfp construct was linearized with scai and injected in vitro into x. tropicalis fertilized embryos at the one-cell stage ( pg of linear plasmid dna in nl of water) as described previously [ , ]. tadpoles were scored for expression of rfp in the lens after stage [ ]. rfp-positive tadpoles ( positive from injected, . %) were selected and raised to adulthood and outcrossed to determine germline transmission of the transgene. male frog caggs-sb ;gcrfp m pro- duced progeny that expressed rfp robustly in the lens and was selected for further analysis. husbandry and micro-injection of x. tropicalis x. tropicalis tadpoles were maintained at °c in static tanks and were staged according to nieuwkoop and faber [ ]. adult animals were housed in a recirculating aquarium at °c. transgenic adult frogs were identified by implanting a radio-frequency identification microchip (microsensys gmbh, erfurt, germany) beneath the skin of the dorsal surface of each animal [ ]. the unique -digit alphanumeric sequence encoded on each chip provides a convenient method for identifying individual animals throughout their lifespan. female x. tropicalis animals were pre-primed with a : dilution of human chorionic gonadotropin (hcg) overnight, and primed the day of injection with u of hcg. fertilized eggs were obtained by natural matings. injected eggs were allowed to heal at °c and transferred to tanks for growth at °c [ ]. this project was approved by st. jude children’s research hospital’s institutional animal care and use committee. rt-pcr analysis of sb expression total cellular rna was isolated using the rnaeasy kit (clontech, mountain view, ca, usa) from individual rfp-positive and rfp-negative stage embryos gener- ated by outcross of caggs-sb ;gcrfp m. first strand cdna was synthesized and used as template for p-labelled pcr reactions as described previously [ ]. primers for sb amplification (sb ’-gccgctcag- caaggaaga- ’ and sb ’-gaagacccatttgc- gaccaag- ’) annealed at °c and produced a bp fragment. primers to xenopus a-actin were used as a control for rna recovery. western blot analysis of sb protein in tissues harvested from transgenic frogs whole embryo or adult tissue samples were snap frozen in a dry ice and ethanol bath and stored at - °c. μl of ripa buffer ( mm sodium chloride, mm tris(hydroxymethyl)aminomethane with hydrogen chlor- ide ph . , % (v/v) nonyl phenoxypolyethoxylethanol (ipegal), . % (w/v) sodium deoxycholate, . % (w/v) sodium dodecyl sulfate, x complete protease inhibitor cocktail (roche, indianapolis, in, usa)) was added to the frozen samples, mixed by vortex, extracted with freon ( μl of , , -trichlorotrifluroethane (sigma- aldrich, st. louis, mo, usa)) and centrifuged at , × g for minutes at °c. the upper phase was trans- ferred to a fresh tube and the protein concentration was measured using the bradford assay (bio-rad, hercules, ca, usa). aliquots of each sample were diluted with an equal volume of × laemmli sample buffer containing b-mercaptoethanol (bio-rad) and denatured by heating at °c for minutes. proteins were separated by elec- trophoresis on % to % (w/v) criterion precast polya- crylamide gels (bio-rad); pre-stained sds-page standards (bio-rad) were used as molecular weight mar- kers. proteins were transferred to hybond-p polyvinyli- dene difluoride (pdvf; ge healthcare life sciences, piscataway, nj, usa) membranes at v for . hours at °c. protein transfer was verified by staining the membrane with ponceau s. monoclonal anti-sb trans- posase antibody (mab ; r&d systems, minneapolis, mn, usa) was resuspended at a final concentration of μg/ml and diluted : to probe the membranes yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of blocked with superblock (pierce, rockford, il, usa) containing . % (v/v) tween . a secondary goat anti-mouse horseradish peroxidase-conjugated antibody was diluted to : , and developed using the chemi- luminescent detection system (pierce). membranes were stripped with restore western blot stripping solu- tion (pierce) and re-probed with a mouse monoclonal antibody specific for xenopus b-actin (ab ; abcam, cambridge, ma, usa) as a control for protein recovery. fluorescent protein expression analysis a leica fliii fluorescent dissecting microscope was used to analyze gfp and rfp expression. digital images were captured using a nikon ri color digital camera and the nikon elements basic research software pack- age (nikon, melville, ny, usa). tadpoles were immobi- lized for photography by brief anesthesia in . % (w/ v) tricaine methanesulphonate. southern blot hybridization genomic dna was harvested from individual tadpoles by overnight proteinase k digestion at °c and phenol/ chloroform/isoamyl alcohol extraction using standard protocols [ ]. genomic dna ( μg to μg) was digested with bglii, separated on a . % (w/v) agarose gel and transferred to hybond n+ hybridization transfer mem- branes (ge healthcare life sciences, piscataway, nj, usa). the hybridization membranes were probed with a p-radiolabeled fragment of the gfp open reading frame (approximately bp) and exposed onto a ge healthcare life sciences phosphorimager screen for detection. genomic pcr and transposon integration site analysis integration site analysis was performed epts lm-pcr to the right arm (ir/dr) of the sb transposon as described previously [ , ]. the integration sites were verified using genomic pcr strategies with primers that bind to scaffold sequences beyond the epts lm-pcr products. pcr primers were also designed to amplify the predicted sequences that flank the left ir/dr of the sb transposon. all genomic pcr products were cloned into either pgem-t easy (promega) or topo-ta (invitrogen, carlsbad, ca, usa) and sequenced. novel sequences were queried against the joint genome insti- tute x. tropicalis genome (version . ; http://genome.jgi- psf.org/xentr /xentr .home.html) and scaffolds were assigned to chromosomes and linkage groups based on the genetic map developed at the university of houston [ ]. list of abbreviations bp: base pair; caggs: chicken β-actin promoter coupled with a cytomegalovirus enhancer; epts lm-pcr: extension primer tag selection linker-mediated polymerase chain reaction; fish: fluorescence in situ hybridization; gfp: green fluorescent protein; hcg, human chorionic gonadotropin; ir/dr: indirect repeat/direct repeats; pcr: polymerase chain reaction; rfp: red fluorescent protein; rt: reverse transcriptase; sb: sleeping beauty; utr: untranslated region. acknowledgements we thank cheryl winter for animal husbandry, drs david largaespada and robert grainger for providing plasmids (pcaggs-sb and . g -crystallin- rfp, respectively). we thank the following st. jude children’s research hospital shared resources: the hartwell center of bioinformatics and biotechnology for dna sequencing and bioinformatics support; the cytogenetics lab for fish analysis; and the animal resource center. support for this study was provided by the national institutes of health (hd , mh to pem and hd to aks and dew) and by the american lebanese and syrian associated charities (pem). author details department of pathology, st jude children’s research hospital, danny thomas place, memphis, tn , usa. department of biology and biochemistry, university of houston, houston, tx , usa. authors’ contributions day carried out embryo injections, scored tadpoles, performed molecular analysis of transposon integration sites and helped prepare the manuscript. cmk performed molecular analyses of transposon integration sites, scored tadpoles and helped prepare the manuscript. ek performed embryo injections, scored progeny, assisted with molecular analyses and helped with general husbandry. hz performed embryo injections and helped score progeny. mrjh generated the sb transposase transgenic line. aks and dew provided mapping data to assign sequence scaffolds to the x. tropicalis linkage groups and/or chromosomes. pem conceived the study, directed the project and wrote the manuscript. all authors read and approved the final manuscript. competing interests the authors declare that they have no competing interests. received: july accepted: november 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http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract bioreactors: stable expression of human alpha- -antitrypsin by a flock of sheep. biotechnology (n y) , : - . . clark kj, balciunas d, pogoda hm, ding y, westcot se, bedell vm, greenwood tm, urban md, skuster kj, petzold am, ni j, nielsen al, patowary a, scaria v, sivasubbu s, xu x, hammerschmidt m, ekker sc: in vivo protein trapping produces a functional expression codex of the vertebrate proteome. nat methods , : - . . yergeau da, kelley cm, zhu h, kuliyev e, mead pe: transposon transgenesis in xenopus. methods , : - . . doherty jr, zhu h, kuliyev e, mead pe: determination of the minimal domains of mix. /mixer required for endoderm development. mech dev , : - . doi: . / - - - cite this article as: yergeau et al.: remobilization of sleeping beauty transposons in the germline of xenopus tropicalis. mobile dna : . submit your next manuscript to biomed central and take full advantage of: • convenient online submission • thorough peer review • no space constraints or color figure charges • immediate publication on acceptance • inclusion in pubmed, cas, scopus and google scholar • research which is freely available for redistribution submit your manuscript at www.biomedcentral.com/submit yergeau et al. mobile dna , : http://www.mobilednajournal.com/content/ / / page of http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract http://www.ncbi.nlm.nih.gov/pubmed/ ?dopt=abstract abstract background results conclusions background results generation and analysis of transgenic x. tropicalis expressing sb transposase generation of double-transgenic ‘hopper’ frogs f hoppers m hoppers discussion sb transposons can be remobilized in x. tropicalis why are different integration mechanisms observed with the co-injection and the double transgenic strategies? potential uses for sb remobilization in x. tropicalis conclusions sb transposons stably integrated into the x. tropicalis genome are substrates for remobilization sb transposon remobilization as a tool for genetic manipulation of x. tropicalis methods plasmids and generation of transgenic lines husbandry and micro-injection of x. tropicalis rt-pcr analysis of sb expression western blot analysis of sb protein in tissues harvested from transgenic frogs fluorescent protein expression analysis southern blot hybridization genomic pcr and transposon integration site analysis acknowledgements author details authors' contributions competing interests references untitled sleeping beauty and the beast (of pervasive transcription) domenico libri institut jacques monod, cnrs-université paris diderot, paris cedex , france in a movie, good bye lenin, the protagonist’s mother, living in east berlin in , enters a coma just before the fall of the berlin wall and the reunification of germany. when she wakes up, her son makes all possible efforts to conceal the changes, as the shock would jeopardize the mother’s frag- ile health. to this end, he builds up an old east germany world around her—up to the restoration of a lost east germany pickles brand using jars recovered from garbage. a transcription scientist that would have slept through the last fifteen years or so would probably be disconcerted to a similar extent when going back to the bench. this modern sleeping beauty would probably feel fuzzy discovering the complexity and diversity of the new transcription world (and, of course, its contradictions) pretty much as if jumping from an old east germany grocery store to a modern super- market. she/he would probably trash results confusing gene expression and transcriptional activity, and would certainly loose her/his positivistic faith in the accuracy of mother nature when dealing with transcription initiation. sleeping beauty might regret the old comfortable drawings depicting regions of transcription as definite boxes driven by well-de- fined promoters firing to deliver a well-defined message, and would definitely forget the notion that rna is just an intermediate in the flow of genetic information from the dna to the protein. but she/he would also dig out from the trash many “artifacts” and “crazy” stories, including the unexplained association of intragenic sequence variants to human diseases—east germany pickles. the fall of the berlin wall in this fantasy is the discovery that transcription occurs almost everywhere in the genome, overlapping annotated transcription units in the sense or an- tisense direction, initiating in a rather promiscuous manner outside or inside genes. and many of these transcription events are hidden by the fact that their rna product—the traditional landmark of transcription—is often undetectable because degraded by nuclear or cytoplasmic pathways. the discovery of pervasive transcription owes much to the devel- opment of high throughput approaches for analyzing the transcriptome, and in particular to tiling microarrays. the first reports describing a vast repertoire of transcripts derived from non-annotated regions (or antisense to annotated re- gions) were published in the early s, from the gingeras, rotman, shoemaker labs in the human system, the ecker, white, and steinmetz labs in other eucaryotes (including yeast) and the church lab in bacteria. in we published what is probably the first report of hidden transcription, i.e., transcription generating rnas that are not sufficiently stable to be detectable above current sensitivity thresholds. this was a fortunate encounter of unexplained results from three teams. analyzing the transcriptome of a nuclear rna degradation pathway mutant (rrp △), a. jacquier had no- ticed unexpected signals deriving from intergenic regions. we had observed that rna pol ii chip signals from “nega- tive” controls (i.e., “non-transcribed” intergenic regions) were sensitive to mutations in transcription initiation factors. the séraphin lab was working on a poly(a) polymerase of unknown function. together, these data were the starting point for demonstrating the existence of a class of rnas that we called cryptic unstable transcripts or cuts: these are produced outside canonical transcription units and de- graded by the nuclear exosome after polyadenylation by a non-canonical poly(a) polymerase. the ares and the toller- vey labs had similar data that were published shortly after. since then, the coverage of the genome by the annotation of non-coding, stable and unstable rnas has increased con- tinuously. high-resolution genome-wide maps of non-cod- ing rnas in yeast have been provided by the jacquier, steinmetz, morillon, and, more recently, the cramer and the corden labs. very few “blank” spaces are left in the sac- charomyces cerevisiae genome, with the suspicion that they have not yet been filled in by the right study. key findings from these studies have drastically modified the way we used to think about transcription. one of these is that by de- fault promoter firing appears to occur in a bi-directional manner, and in many cases the two directions are not equiv- alent in terms of functional significance (e.g., a protein cod- ing gene in one direction and a non-coding rna without established function in the other). although work from many teams, including the weissman, the proudfoot, and the buratowski labs, have demonstrated that transcription in the most informative direction (e.g., a protein coding corresponding author: libri.domenico@ijm.univ-paris-diderot.fr article and publication date are at http://www.rnajournal.org/cgi/doi/ . /rna. . . freely available online through the rna open access option. © libri this article, published in rna, is available under a creative commons license (attribution-noncommercial . international), as de- scribed at http://creativecommons.org/licenses/by-nc/ . /. rna : – ; published by cold spring harbor laboratory press for the rna society cold spring harbor laboratory press on april , - published by rnajournal.cshlp.orgdownloaded from http://www.rnajournal.org/cgi/doi/ . /rna. . http://www.rnajournal.org/cgi/doi/ . /rna. . http://www.rnajournal.org/cgi/doi/ . /rna. . http://www.rnajournal.org/site/misc/terms.xhtml http://creativecommons.org/licenses/by-nc/ . / http://creativecommons.org/licenses/by-nc/ . / http://www.rnajournal.org/site/misc/terms.xhtml http://rnajournal.cshlp.org/ http://www.cshlpress.com gene) is generally preferred, “reverse direction” firing is far from been negligible and generally leads to the production of non-coding, non-functional rnas that may overlap neigh- boring transcription units. another important—and largely unexpected—established principle is that the control of ini- tiation is inherently leaky. paradoxically, it could be argued that more information is required to prevent transcription initiation than to promote it. this is maybe best illustrated by the demonstration, for instance by the winston and the workman labs, that disfavoring nucleosome re-assembly in the wake of transcribing polymerase leads to frequent intra- genic transcription initiation at positions where initiation is not presumed to be selected for function. the nucleosomal structure of chromatin is an obstacle for the initiation of transcription. transcription leading to the production of “pervasive transcripts” (such as cuts) might require poor sequence informational content to initiate once a breach in such a repressive chromatin structure is found. the third important lesson from these years of hidden transcription studies is that steady state rna levels are only partial bench- marks of transcriptional activity. degradation pathways, both nuclear and cytoplasmic, have clear and major roles in shaping the transcriptome. work from many labs, including ours, has demonstrated that the rna landscape in the absence of key degradation enzymes, such as the exosome, xrn and nonsense mediated decay factors is drastically different. studies on hidden transcription, pioneered in yeast, have extended to metazoans. a seminal work published in from the jensen lab has revealed the occurrence of hidden rna production in humans (prompts, promoter proximal transcripts), detected, as in yeast, when degradation is de- fective. parallel studies from the sharp and lis labs dem- onstrated that promoters of mouse and human genes fire bidirectionally, extending the analogy with the fungal system. pervasive transcription is dangerous for the stability of the transcriptome: if concurrent transcription is generally toler- ated in regions of elongation, transcription through promot- er regions generally inhibits their function—a phenomenon known as transcription interference. failing the establish- ment of a robust control on initiation, the cell has developed systems to confine transcription that has started inappropri- ately, which, both in yeast and the metazoan systems, rely heavily on transcription termination and, to a lesser extent, on the degradation of the rna produced. but the beast of pervasive transcription is probably so only at first sight, as in the tale. some of the non-canonical tran- scription events have been shown to have a regulatory func- tion, via the non-coding rna produced or the act of transcription itself. the share of non-canonical transcrip- tional events that have a function is forever growing. maybe the most striking example is the accumulation of dna vari- ants mapping to regions that do not contain annotated genes and that have been linked to human diseases by genome-wide association studies (gwas). these sites have been calculated to represent % of gwas hits: one of the possible explana- tions for these variants is that some of these mutations alter the sequence of a non-coding rnas that might be involved in regulation. the nature of the regulatory event linked to non-canonical transcription generally appears to be different in the different systems (e.g., yeast versus human cells): if in human cells (and many other organisms including s. pombe) many non-coding rnas have been convincingly shown to be in- volved in the control of gene expression, in s. cerevisiae it is essentially the act of transcription itself, and not the non-cod- ing rna produced, that functions in regulation. however, it is very likely that the functional cases will re- main a small minority of the bulk of pervasive transcription, although this is still the subject of intense debate. thus, the question that haunts the transcription field remains: what is the ultimate advantage of such a “consum- eristic” strategy in producing in excess to discard a large frac- tion rather than more strictly targeting the production to the cellular needs. many hypotheses have been formulated. extended offer of (often superfluous) goods stimulates con- sumer demand, sometimes helping to identify successful products. this leads to economically justifying the waste. ex- tended expression of the information written on the dna might be a more efficient way to evolve new functions, as mu- tations arising in transcribed regions have higher chances of being exposed to natural selection than mutations in silent regions. in this perspective, the bulk of pervasive transcripts might represent an important depository of rna variants that have gone one step further on the path to function. developing systems to increase the specificity of transcription would not only restrict such a source of variability, but might also have a high evolutionary cost, especially if the intrinsic propensity of the polymerase to initiate transcription is mechanistically linked to essential features of the transcrip- tion process (e.g., the stability of the elongation complex). but overall, the real appearance of the prince that hides be- hind the beast of pervasive transcription remains quite mys- terious, and is a challenge for many future studies. sleeping beauty and the beast (of pervasive transcription) www.rnajournal.org cold spring harbor laboratory press on april , - published by rnajournal.cshlp.orgdownloaded from http://rnajournal.cshlp.org/ http://www.cshlpress.com : - rna domenico libri sleeping beauty and the beast (of pervasive transcription) open access open access option.rnafreely available online through the license commons creative .http://creativecommons.org/licenses/by-nc/ . / (attribution-noncommercial . international), as described at , is available under a creative commons licensernathis article, published in service email alerting click here.top right corner of the article or receive free email alerts when new articles cite this article - sign up in the box at the http://rnajournal.cshlp.org/subscriptions go to: rnato subscribe to © libri; published by cold spring harbor laboratory press for the rna society cold spring harbor laboratory press on april , - published by rnajournal.cshlp.orgdownloaded from http://creativecommons.org/licenses/by-nc/ . / http://rnajournal.cshlp.org/cgi/alerts/ctalert?alerttype=citedby&addalert=cited_by& savealert=no&cited_by_criteria_resid=rna; / / &return_type=article&return_url=http://rnajournal.cshlp.org/content/ / / .full.pdf http://rnajournal.cshlp.org/cgi/adclick/?ad= &adclick=true&url=https% a% f% fhorizondiscovery.com% fen% fcustom-synthesis% fcustom-rna% futm_source% dcshl_rna% utm_medium% dbanner% utm_campaign% dcustom_synth% utm_term% doligos% utm_content% djan http://rnajournal.cshlp.org/subscriptions http://rnajournal.cshlp.org/ http://www.cshlpress.com quaderni d'italianistica : revue officielle de la société canadienne pour les études italiennes = official journal of the canadian society for italian studies, piccola biblioteca nell'artificio dichiarato nel sottotitolo del volume e si offre come chiave interpretativa, se non dcll'inlcra civiltà barocca, dei suoi prodotti narrativi più estesi. il punto di partenza e tasso, o meglio la struttura "diparabolica," a parabola rove- sciata, della liberata, che mostra una iniziale "catadromìa" del racconto, e cioè una corsa verso il basso che giunge al termine estremo con la siccità in campo cristiano, cui succede una "anadromia" ( ), che corrisponde ad una risalila culminante con la conquista della rocca e lo scioglimento del voto. la doppia direzione del narrato è il segno più evidente di una serie di opposizioni, a tutti i livelli retorici, sparse con dovizia nell'intero poema. il motivo dell'antitesi si accentua in oraziani, che aveva tra l'altro alle spalle l'espe- rienza ancora vitalissima écwacionc mariniano, fino alla presentazione di una molte- plicità di punti di vista sul medesimo evento che gioca contro la linearità dell'azione. notiamo quindi che "la ripetizione dello stesso lasso temporale si accompagna ali ado- zione successiva di fuochi prospicienti, cóll'ultimo risultato di rendere essi reciproci, e commutabili cause ed effetti" ( ). ecco quindi in oraziani, "vero teoreta di dif- ferenziali e integrali," erede del marino, precisata, nel passaggio da meccanicismo a finalismo, la tensione dello spirito barocco: ". . . in oraziani ... è effettivamente sottesa alla maniera di raccontare una concezione organismatica del reale e dei nessi che vi si intrecciano, visti (al di là d'un determinismo capace di riguardare non più che l'apparenza) nella loro infinibile interrelazione, cioè dall'alto di una metastoria la quale discorra per intenzioni e insomma teleologicamentc" ( ). le sapide conclusioni sono avallate da una ricca ed elaborata esemplificazione. il materiale d'analisi si raccoglie in un riassunto dettagliato dei canti del poema, inserito nel volume e opportunamente frazionato in segmenti numerati. la parte sag- gistica consta in effetti di quaranta densissime pagine di ardua lettura (zeppe di termini che invano si cercherebbero nel nuovo palazzi e in un comune manuale di retorica). notevole ricchezza di riferimenti, con schede rare ma sempre pertinenti, si registra nelle note a pie' di pagina. francesco guardiani university of toronto gregory l. lucente, beautiful fables: self-consciousness in italian narrative from manzoni to calvino. baltimore: the john hopkins university press, . pp. . while self-consciousness is undeniably more pervasive in our self-indulgent and frag- mented world, it is unwise, if not self-consuming, for critics to mirror this abortive state of affairs. prof. lucente has mercifully not pursued this self-destructive course, nor has he pedantically tried to catalogue his theme. what he has done, and done well, is to demonstrate how the question of worldly praxis and literary representation affect both narrative and linguistic consciousness in selected italian authors. it is not a standard critical account; it does not claim to be so. lucente is not interested in the "narrative o/ self-consciousness" per se but rather the "history of self- consciousness in narrative" ( ). this explains his choice of texts which range from the highly self-conscious meta-commcntary of oadda, to the more concrete and repor- torial fiction of silone. this asymmetry may initially lead one to question lucente's piccola biblioteca seemingly all inclusive approach: will he find self-consciousness everywhere? yet by very shrew/dly manipulating the paradigm of self-consciousness, lucente develops a unique methodological tool for weighing the import of this style in individual texts where the performance, in itself, does not constitute a genre. he thus admirably suc- ceeds in rendering a seemingly arbitrary collection of familiar works into a subjective and poignant reappraisal of modern italian literature. lucente has limited himself to italian authors because he wishes to examine "real historical changes" not "a priori paradigms ... of literary genealogies" ( ). in doing so he fills a lacuna in italian criticism which has self-consciously (no pun intended) avoided critical inquiry into the fundamental question of literary self-consciousness. the chapters of the book (plus introduction and conclusion) are devoted to the following authors: : manzoni; ii: verga; iii: dossi and d'annunzio; iv: pirandello; v: svevo; vi: silone; vii: lampedusa; vili: gadda; ix: morante; x: calvino; xi: samona, manganelli, eco. the sections on verga, morante, and calvino are perhaps the best parts of the book. beautiful fables is a major contribution to the study of self-conscious narrative. lucente provides not only a sustained and informative reading of the texts he exam- ines but collates detail with personal impressions which flesh out the more narrow component theme of self-consciousness. in truly humanist fashion, lucente affirms the "why" of narrative hors texte while eloquently leading his reader into the post- modern realm of narcissus, where writing is pure desire. a highly readable style communicates a sense of authority and freshness. franco ricci university of ottawa matilde serao. // romanzo della fanciulla. a cura di francesco bruni. na- poli: liguori, . pp. . il presente volume raccoglie sei racconti tutti appartenenti alla prima maniera della serao, e cioè ai suoi esordi naturalistici. telegrafi dello stato, per monaca, nella lava. scuola normale femminile e non più furono tutti pubblicati su riviste dell'epoca fra il e il . la virtù di checchina apparve, invece, per la prima volta a puntate nel , e non fa parte, propriamente, del romanzo della fanciulla. ambientati quasi esclusivamente nella piccola borghesia napoletana, e considerati unanimamente fra le cose migliori scritte dalla serao, questi racconti sono notevoli anche perché costitui- scono una testimonianza importante delle difficoltà incontrate dalla serao nella sua breve ricerca di una voce letteraria al di fuori degli stereotipi collaudati dalla tradizio- ne. difficoltà tali, che, come ben si sa, la scrittrice finì per abbandonare la felice vena naturalista per accostarsi sempre di più al romanzo di consumo. non però, come si è soliti pensare, per pigrizia e per mancanza di disciplina (fu renato serra a suggerire questa formula per primo), ma per ragioni obbiettive, legate alla sua posizione di donna, e più particolarmente di donna-scrittrice. vorrei cogliere l'occasione offertami dalla ristampa di questi racconti per fermarmi su quest'ultimo punto e proporre un'interpretazione un po' diversa dell'evoluzione — o piuttosto involuzione — della serao, e cioè del motivo per cui ha finito, nonostante gli esordi felici, per dedicarsi ad una narrativa tutta scontata e di scarso valore letterario, untitled © v.m. pudalov, fizika nizkikh temperatur, , v. , no. , p. – david shoenberg and the beauty of quantum oscillations v.m. pudalov p.n. lebedev physical institute, leninskii prospekt, moscow , russia e-mail: pudalov@lebedev.ru received august , the quantum oscillation effect was discovered in leiden, in , by w.j. de haas and p.m. van alphen in magnetization measurement, and by l.w. shubnikov and de haas — in magnetoresistance. studying single crystals of bismuth, they observed oscillatory variations of magnetization and magnetoresistance with magnetic field. shoenberg, whose first research in cambridge had been on bismuth, found that much stronger oscillations are observed when a bismuth sample is cooled to liquid helium rather than to liquid hydrogen, which had been used by de haas. in shoenberg came from cambridge to moscow to study these oscillations at kapitza in- stitute where liquid helium was available at that time. in , j. marcus observed similar oscillations in zinc, that persuaded shoenderg to return to this research, and, since then, the dhva effect had been one of his main research topic. in particular, he developed techniques for quantitative measurements of the effect in many met- als. theoretical explanation of quantum oscillations was given by l. onsager in , and the analytical quantit- ative theory by i.m. lifshitz and a.m. kosevich in . these theoretical advancements seemed to provide a comprehensive description of the effect. since then, quantum oscillations were commonly considered as a tool for measuring fermi surface extremal cross-sections and all-angle electron scattering times. however, in his pio- neering experiments in s, shoenberg revealed the richness and deep essence of the quantum oscillation ef- fect and showed how the beauty of the effect is disclosed under nonlinear conditions imposed by interactions in the system under study. it was quite unexpected, that under «magnetic interaction» conditions, the apparently weak effect of quantum oscillations may lead to such strong consequences as breaking the sample into magnetic (now called «shoenberg») domains and the formation of an inhomogeneous magnetic state. owing to his contri- bution to the field of quantum oscillations and superconductivity, shoenberg is no doubt one of the th cen- tury's foremost experts. we describe the experiments on finding the quantitative parameters of electron–electron interaction, which are in line with the shoenberg ideas that the quantum oscillations are modified by interactions and, hence, their analysis enables one to extract the quasiparticle interaction parameters. pacs: . .+h metal–insulator transitions and other electronic transitions; . .rn localization effects (anderson or weak localization); . .qv metal–insulator-semiconductor structures (including semiconductor-to-insulator). keywords: quantum oscillations, two-dimensional carrier system, electron–electron interaction. . introduction: correspondence with david shoenberg it is a privilege to be invited to contribute to this vo- lume in honour of professor david shoenberg with whom i had an opportunity to communicate and whose papers i studied thoroughly in the past. in the early s, i was a graduate student at the famous institute for physical problems in moscow, which is now named after p.l. ka- pitza. though i have never met david shoenberg personal- ly, of course, i knew much about his work with kapitza in cambridge and in moscow and about his visits to kapitza institute in s. a few years earlier, in , my scien- tific supervisor, the outstanding experimentalist and teacher, m.s. khaikin, suggested me to develop a super- sensitive dilatometer, as a topic for gradate project. the dilatometer, i.e. a device for measuring small displace- ments, was intended for measuring changes in the sample size in magnetic field. the microwave technique was the favorite subject in the khaikin laboratory, and, not surpri- singly, the dilatometer was a sort of a microwave cavity with a thin copper membrane and a needle-type coaxial conductor, which concentrated microwave energy near the region of the membrane deformation. david shoenberg and the beauty of quantum oscillations fizika nizkikh temperatur, , v. , no. when my dilatometer started working reliably, it ap- peared that i could easily observe the nice phenomenon of quantum oscillations of size of the metallic single crystals placed in varying magnetic field at low temperatures. the oscillatory magnetostriction had, of course, the same origin as the de haas–van alphen (dhva) effect, and from its amplitude i anticipated to extract information on electron coupling to the lattice potential, that is the so-called de- formation potential. i was encouraged with this observa- tion and ignored a common wisdom that says «avoid quan- titative amplitude measurements when possible». quite soon i realized that the measurements of the magnetostric- tion amplitude alone is insufficient to get quantitative in- formation. in order to extract components of the deforma- tion potential tenzor, one has also to measure the amplitude of the oscillatory magnetic moment, i.e., the dhva effect. experimentalists know perfectly that absolute ampli- tude measurements for a single effect is a hard task, and amplitude measurements for two effects are still much harder. in those times, david shoenberg carried out nice absolute measurements [ , ] of the dhva effect amplitude, and each of his papers represented a piece of experimental art and deserved careful reading. however, the technique he used was incompatible with my microwave cavity dila- tometer. clearly, measurements of the two effects should be performed in situ during a single cooldown, because the oscillation amplitude is determined not only by controlla- ble variables (temperature, magnetic field), but also by the sample «quality» (more exactly, the dingle temperature [ ]), which may vary from one cooldown to another. the solution to the problem was found heuristically: it unexpectedly came during the experiment and had a direct relation to david shoenberg! the situation was as follows: in my measurements, for signal extraction from noise, i used not a conventional field modulation technique with a lock-in amplifier and a slow magnetic field sweep, but an alternative technique with a multichannel analyzer and fast multiple sweeps of magnetic field within several seconds [ ]. the measuring system was based on the frequency modulation method, developed by m.s. khaikin and re- presented a heterodyne microwave receiver. variations of the crystal size were measured as changes in frequency of the microwave oscillator that had the cavity — displace- ment sensor — in the feedback loop. for convenience, in the khaikin laboratory, the experimental data was not only recorded by electronics but was also available to experi- mentalists in visual and audio form. correspondingly, the intermediate frequency signal transposed to the audio range was fed, besides a frequency detector, to an ordinary loudspeaker. taking measurements of the oscillatory mag- netostriction late in the evening, in the silent laboratory, i heard that, upon cooling the sample down to . k, the tone of the audio frequency signal began to vary abruptly with magnetic field in a saw-tooth manner, rather than harmonically (see fig. ). the first thought that in magnetic field the sample was cracking was rejected at once, because on subsequent warming of the sample up to . k, the oscillations became harmonic again, as expected. the observed unharmonicity was much greater, than one could expect from the lif- shitz–kosevich (lk) theory [ ]. therefore, the more natu- ral assumption was to associate the saw-tooth oscillations with the so-called shoenberg effect and magnetic domains [ ]. indeed, despite the smallness of the magnetic moment oscillations ,mδ i.e., the amplitude of the dhva effect, the oscillation period in good metals with a large fermi surface (such as tin and indium under my investigation) is small and, therefore, the magnetic susceptibility | / |m b∂ ∂ becomes comparable with / π . as a result, the magnetic induction in the sample b noticeably deviates from the external magnetic field h : = ( ) .b h d m+ π − ( ) the deviation leads to the magnetic interaction or the shoenberg effect [ ] (here d is the demagnetization fac- tor), that is described by solution of the exact nonlinear equation [ ] sin . ( ) r c r m a h d m ∞ ν ⎡ ⎤ω⎛ ⎞ ⎢ ⎥⎜ ⎟+ π −⎝ ⎠⎣ ⎦ ∑∑∼ v ( ) as soon as the unharmonicity cause was identified, to make the next step was a matter of not too sophisticated though rather awkward calculations. using sequential ap- proximation technique i have calculated the discrete spec- trum of oscillations. the obtained series converged rapidly and delivered a striking result: the desired amplitude of the magnetization oscillations could be found from the ratio of harmonics in the oscillatory magnetostriction spectrum. therefore, the problem of simultaneous amplitude mea- surements for two effects reduced to measurements of the amplitude for only one of them supplemented with subse- quent analysis of its spectrum. fig. . typical shape of the quantum oscillations of magneto- striction u of tin single crystal versus magnetic field. bracket next to the upper curve depicts the magnetostriction scale. tem- perature . t = k, | / | . dm dhπ ≈ : a) for || [ ]h and b) for h tilted at ° in the ( ) plane. the lower curve reveals two groups of oscillations with frequency ratio : ≈ , due to two extremal cross-sections of the fs. note a saw-tooth shape of os- cillations. reproduced from ref. . а b – h, oe v.m. pudalov fizika nizkikh temperatur, , v. , no. this situation can be explained in the following way. suppose we have a pendulum (oscillator) and wish to mea- sure the amplitude of its oscillations, but there is no cali- brated ruler to measure linear displacements. then, for har- monic oscillator the problem has no solution. it appears, however, that for an unharmonic oscillator, when the phys- ics of its unharmonicity is known, the oscillation amplitude may be found by registering the oscillation spectrum and analyzing the spectrum with a linear but uncalibrated ruler. when the calculations of the oscillations spectrum were finished and successfully compared with experimental da- ta, i was proud and assured with the result. it seemed con- vincing to me, and i was about to send the paper for publi- cation. however, not all around me in the lab shared my assurance. the major expert in the field of quantum oscil- lations was certainly david shoenberg and i decided to consult with him: i wrote a letter (e-mail didn't exist at that time) where i described my idea how the oscillation ampli- tude could be found from their spectrum under conditions of the magnetic interaction*. i was not sure that the famous scientist will answer to unknown graduate student. how- ever, i was pleased to get a short note from shoenberg quite quickly: he wrote that currently was busy but in a couple of weeks will be able to answer. i waited for about two weeks and indeed received a very kind letter: shoen- berg was positive about my idea, and also paid my atten- tion to a potential «underwater stones», such as deviations from the conventional lk theory of oscillatory effects [ ], which might be related, e.g., with mosaic structure of crys- talline samples. these were the issues he studied at that time [ ]. my paper was sent to the journal and published shortly [ ]. i keep in memory the kind attention shoenberg showed to an unknown graduate student, and try to educate my students in the same spirit of kindness and respect to others. . interacting two-dimensional electron system the experiments by shoenberg demonstrated how the hidden beauty and rich essence of quantum oscillations are revealed in nonlinear conditions introduced by magnetic interaction. with another example of the beauty and rich- ness of the quantum oscillations i faced much later, study- ing the electron–electron interaction effects in two-dimen- sional electronic system. this story is described below. for pedagogical purposes, the story is delivered in the sequence as follows: firstly, we consider how the inter- particle interaction modifies parameters of the electronic system, as compared with those for noninteracting gas. the interaction effects will be initially described, to a first ap- proximation, in terms of the fermi-liquid interaction con- stants. further, we will consider the experimental method and the results of measurements of the fermi-liquid inter- action constants, where quantum oscillations are used as an experimental tool. we will presume first that the oscilla- tion amplitude is small and is not strongly affected by inte- raction. and finally, we will consider how the inter- electron interaction influences the quantum oscillation am- plitude and what consequences it leads. . . renormalization of the quasiparticle parameters as an introduction, let us first recall that one of the ma- jor concepts for interacting fermi systems is the fermi liquid. it is the generalization of the fermi gas, i.e. the sys- tem without interaction, to the case with interaction. the electrons in d metal or «metallic» d systems are charg- ed and, at first sight, seem to experience a great coulomb repulsion forces / eee r∼ , where eer is the interelectron distance; for d systems ~ /eer n , where n is the electron density. in fact, these classical forces are compensated by ion lattice, because the total system is neutral. at low energies which matter most to us, additional (or trial) charges introduced to the system do not interact via the coulomb potential. this is so, since the charges polarize their environment. in d, the long-range interaction has effectively been reduced to a short range one with a po- tential sc( ) exp ( / ) /r r r rφ ∝ − where scr is the screening length. the fourier transform of the screening effect reads / / ( )sq q q→ + , where sq is the thomas–fermi wave vector which is inverse proportional to the screening length sc .r in contrast to the d case, in d system the screening effect is much weaker. for large distance srq , the asymptotic form of the average potential seen by the elec- trons [ ] does not show an exponential decay ( ) s e r q r φ ∝ . ( ) the essential idea on which fermi-liquid theory is based was introduced by landau. even if the bare particles interact strongly, the low energy elementary excitations experience only a weak or moderate interaction. these elementary excitations are called quasiparticles. the quasi- particles can be labeled by the same quantum numbers as the excitations in the noninteracting system. in particular, in the vicinity of the fermi surface they behave as if they were free fermions. in the absence of magnetic field the quasiparticles have the same charge and spin as free elec- trons, and for short, we shall call them «electrons». the in- teraction strength is characterized by the dimensionless ra- tio of the potential interaction energy eee to the kinetic (fer- mi) energy, = / = / /s ee fr e e me n nκ π ∝ (here the factor of takes the valley degeneracy in ( )-si mosfets, = gv , into account). within the framework of the fermi-liquid theory, the interactions lead to renormalization of the effective quasi- particle parameters [ , ], such as the spin susceptibility * this was the lucky time, when physicists shared with each other unpublished results, thoughts, and samples. david shoenberg and the beauty of quantum oscillations fizika nizkikh temperatur, , v. , no. *χ , effective mass * ,m landé g-factor *g , and compres- sibility *κ . measurements of these renormalized parame- ters are the main source of experimental information on interactions. the renormalization is commonly described by harmonics of the fermi-liquid interaction in the singlet (symmetric, (s)) and triplet (antisymmetric, (a)) channels [ , , ]: * = ab g g f+ , * = s b m f m + , * * = sb b m m f κ κ + , * * = ab b m m f χ χ + . ( ) here bg , bm , bκ and bχ are the band (bare) values of the g-factor, mass, compressibility and spin susceptibility, respectively. in theory, the above fermi-liquid interaction constants ,a sif are universal functions of the sr solely. provided the fermi-liquid constants are known, the charac- teristics of the interacting d electron system to the first order can be expressed as interaction quantum corrections to the characteristics for the noninteracting d electron gas. though the results of numerical calculations of the re- normalized parameters [ – ] vary considerably, all of them agree qualitatively and suggest enhancement of *χ , *m and *g with sr . earlier experiments [ – ] have shown growth of *m and * *g m at relatively small sr values, pointing to a ferromagnetic type of interactions in the ex- plored range < . .sr . . quantum oscillations in the d electron gas as a tool for extracting interaction constants for d noninteracting electron gas placed in quantizing magnetic field = zh h , besides the quantized spectrum = ( / )n c nε ω + in the ( , )x yk k plane there is a conti- nuous spectrum along the magnetic field direction ( )zkε . in contrast, for a d system of electrons placed in magnet- ic field h⊥ perpendicular the ( , )x y plane, the energy spectrum is fully quantized: = , c z n e⎛ ⎞ε ω + ±⎜ ⎟ ⎝ ⎠ ( ) where the zeeman energy = z b e g hμ ( ) and = , , ,...n is the landau level number. each of the landau levels is = /h⊥ν Φ times degenerate, and the oscillation period in the inverse magnetic field has a fun- damental meaning being determined by the ratio of the electron density to the magnetic flux density, / ( / ),n h⊥ Φ where = /hc eΦ . for noninteracting d electron gas, the theoretical ex- pression for the shubnikov–de haas (sdh) effect, i.e. the oscillatory magnetoresistance, is as follows [ , ]: = cos ,xx s s s c n a s z eh⊥ ⎡ ⎤⎛ ⎞δρ π π −⎢ ⎥⎜ ⎟ ρ ⎢ ⎥⎝ ⎠⎣ ⎦ ∑ ( ) where / = exp . sinh ( / ) b cb d s c b c sk tk t a s sk t ⎛ ⎞ π ω − π⎜ ⎟ ω π ω⎝ ⎠ ( ) here = ( = )xx h⊥ρ ρ , = /( * )c eeh m m c⊥ω is the cyc- lotron frequency, *m is the dimensionless effective mass, em is the free electron mass. this is the famous lifshitz– kosevich formula [ ], modified for the d case [ ]. an additional exponential factor describes landau level broa- dening due to temperature-independent scattering by short- range impurity potential, / d dt ≡ πτ is the so-called dingle temperature [ ], and dτ is the «all angle» scatter- ing time (in contrast to the transport time τ determined by large angle scattering). in the limit of weak oscillations / xxδρ ρ when temperature is not too low, eq. ( ) can be simplified: * ( ) exp b d bs cc k t t k t a s s ⎛ ⎞+ ≈ − π π⎜ ⎟ ⎜ ⎟ ωω⎝ ⎠ . ( ) in eqs. ( ), ( ) the valley splitting is assumed = gv (that corresponds to the d layer of electrons at the ( )-si surface). the zeeman factor in eq. ( ) = cos [ ( ) / ( )]sz s c n n eh⊥↑ ↓π − ( ) for = h reduces to a field-independent constant. here ( )n n↑ ↓− is the difference in population of the two spin subbands. in case the spin magnetization is a linear func- tion of the total field toth , the nonzero difference in sub- bands populations, i.e. the spin polarization p , can be related to the renormalized spin susceptibility *χ as fol- lows: * tot tot**= = , b b n n h eh p g m n g n nhc ↑ ↓− χ≡ μ ( ) where bg is the bare g-factor for si, and toth = h h⊥= + . bychkov and gorkov [ ] have shown that the period of oscillations is not affected by interactions, whereas oscillation amplitude (eqs. ( ), ( )) is determined by * *= /( )c eeh m m cω with the renormalized mass * ,m ra- ther than the band mass bm , and the zeeman splitting ( ) — by the renormalized g-factor. . . the idea of measurements *χ , *m , and *g experimental studies of magnetooscillations go back to the end of s when the high mobility d structures be- came available [ , ]. information on the renormaliz- ed effective mass *m is provided by the amplitude of the shubnikov–de haas (sdh) effect [ ]. the effective mass is usually found from the so-called dingle-plot, v.m. pudalov fizika nizkikh temperatur, , v. , no. ln (| | / )xxδρ ρ as a function of temperature. according to the lk theory, the damping factor can be expressed as * ** ln ( ) . lk c c da t t mt ⎛ ⎞ω − ω ≈ +⎜ ⎟ ⎜ ⎟ ⎝ ⎠ ( ) as follows from eq. ( ), in the limit of weak oscilla- tions, | | / xxδρ ρ , the slope, ln(| | / ) /xxd dtδρ ρ , is nearly proportional to the effective mass *m , whereas extra- polation of the ln [ ( / )]ca tω to = t enables to deter- mine dt . here, both, the effective mass and the g-factor are thermodynamic quantities and includes all many-body interaction effects. the zeeman factor eq. ( ) carries information on the renormalized spin susceptibility * * *m gχ ∝ . conventional technique to measure the effective *χ [ , ] is based on the sdh measurements in magnetic fields tilted with re- spect to the d plane. in these measurements, the cyclotron energy related to h⊥ is compared with the zeeman split- ting, which depends on the total field, toth . to have a good control of both fields, the angle is to be measured with a very high accuracy, a difficult task at mk tempera- tures. to probe separately orbital and spin degrees of free- dom, it is convenient to apply two independently varied magnetic field components: (i) h⊥ , normal to the d electron plane, which causes quantization of the orbital motion, and (ii) the in-plane field h , which couples only to spins. application of h should facilitate the analysis of sdh oscillations, especially near the d metal–insulator transition, when the number of observable oscillations is small. the idea of measurements with two field components is explained by fig. . the parallel field h shifts the spin- up and spin-down subbands relative to each other in accord with eqs. ( ), ( ), and produces an unequal population of the two subbands (see eq. ( )). the role of the perpendi- cular field component is to provide measurements of the difference in subband population, and thus to extract the spin susceptibility according to eq. ( ). the perpendicular field causes quantization of the energy levels in both sub- bands and enables to count the difference in their individu- al population, because all spin-split landau levels are ex- actly /( / )h hc e⊥ times degenerate. . . crossed field technique in order to facilitate measurements, we developed a «crossed-field technique» [ ] by adding the second sole- noid and taking data in crossed magnetic fields, which can be varied independently of each other (see fig. ). the conventional technique of measuring * *g m in tilted mag- netic fields [ , ] is not applicable when the zeeman energy is greater than half the cyclotron energy [ ]. the crossed field technique removes this restriction and allows us to extend measurements over the wider range of elec- tron densities. development of this novel experimental technique enabled us to explore the effect of h on the electron spectrum, as well as to measure directly *m and *g in strongly correlated selectron systems [ ]. typical traces of the longitudinal resistivity xxρ as a function of h⊥ are shown in fig. . due to the high elec- fig. . schematic diagram of the landau levels in the presence of the zeeman splitting * totbg hμ . the left and right ladders of landau levels are for spin-up and spin-down subbands. tot =h h h⊥ + . � �f � �c h� g* h�b tot si-mosfet mixing chamber of dilution fridge solenoid h|| split coils, h� fig. . the crossed magnetic field set-up. the main supercon- ducting solenoid produces the in-plane magnetic field h up to t. the superconducting split coils, positioned inside the main solenoid, produce the normal field h⊥ , which can be as large as . t at h ≤ t, and decreases gradually down to . t at = . h t. the sample (si-mosfet) is attached to the cold finger of the mixing chamber, with its plane perpendicular to the axis of the coils. represented from ref. . david shoenberg and the beauty of quantum oscillations fizika nizkikh temperatur, , v. , no. tron mobility, oscillations were detectable down to . t and at temperatures up to . k; a large number of oscilla- tions and wide range of temperatures enabled us to extract *m and dt with a high accuracy. as fig. shows, application of h induces beating of sdh oscillations. this is because the uppermost levels in the two spin ubbands move with field at different rates and cross the fermi energy either in phase or out of phase. the beatings are observed as a function of h⊥ and the beat frequency is proportional to the spin polarization of the interacting d electron system .p in experiment, we ob- served a well pronounced beating pattern at a nonzero h (see figs. and ), in agreement with eq. ( ). the phase of sdh oscillations remains the same between the adjacent beating nodes, and changes by π through the node. the interference pattern (including positions of the nodes) is controlled by sz in eq. ( ) and is defined solely by * *.g m systematic study of this pattern enabled us to determine * *g m with high accuracy ( %∼ ). the * *g m values are independent of t (at < k)t within our accuracy [ ]. we have observed a weak dependence of * *g m on h in strong h . to determine * *g m in the linear regime, we systematically measured, for each n , the beating pattern at decreasing values of h until * *g m becomes independent of h . evolution of the beating pattern with h is illu- strated in figs. ,a and b. . . data analysis comparison between the measured and calculated de- pendences /xxδρ ρ versus h⊥ , both normalized by the amplitude of the first harmonic a is shown in fig. for three carrier densities; for the sake of clarity, the oscilla- tions are plotted as a function of the filling factor / h⊥ν ∝ . the normalization assigns equal weights to all oscillations. we analyzed sdh oscillations over the low- field range th⊥ ≤ ; this limitation arises from the as- sumption in eq. ( ) that c fω ε and | | / xxδρ ρ . the latter condition also allows us to neglect the inter-level interaction which is known to enhance *g in stronger fields [ ]. the amplitude of sdh oscillations at small h⊥ can be significantly enhanced by applying h (see fig. ) [ ], which is another advantage of the cross-field technique. indeed, for low h⊥ and n , the electron energy spectrum is complicated by crossing of levels corresponding to dif- ferent spins/valleys. by applying h , one can control the energy separation between the levels, and enhance the am- plitude of low-field oscillations. we have verified that ap- plication of h (up to the spin polarization %∼ ) does not affect the extracted *m values (within % accuracy), (the insets to fig. show that the values of *m measured at = h and . t do coincide). fitting of the data provides us with two combinations of parameters: * *g m and *( )dt t m+ . the first combination, * * / bg m m normalized by the band values, represents the sought-for renormalized spin susceptibility. the measured values of * *g m , as well as *m which are discussed below, were similar for different samples. figure ,a shows that for small sr (high densities), our * *g m values agree with fig. . shubnikov–de haas oscillations for = . · n cm– (si-mosfet sample) at = . kt [ ]. h = t|| h = . t|| . . . h , t� r , k � � r , k � � fig. . examples of fitting with eq. ( ): (a) = . · n cm– , = . t k, = . h t, = p % (the data corresponds to fig. ,b); (b) = . · n cm − , = . h t, = % ;p (c) = . · n cm– , = . t k, = . h t, = p %. the data are shown as the solid lines, the fits (with parameters shown) as dashed lines. all are normalized by ( )a h⊥ . – – a b c m* = . m* = . m* = . g* = . g* = . g* = . h|| = . t h|| = . t h|| = . t p = % p = % p = % n = . n = . n = . . – . � / a � / a � / a h , t� – – v.m. pudalov fizika nizkikh temperatur, , v. , no. the earlier data by fang and stiles [ ] and okamoto et al. [ ]. for sr ≥ , * *g m increases with sr faster than it might be expected from extrapolation of the earlier results [ ]. the second combination, *( )dt t m+ , controls the am- plitude of oscillations. in order to disentangle dt and * ,m we analyzed the temperature dependence of oscillations over the range = . – . kt (for some samples . – . k) . the conventional procedure of calculating the effective mass for low sr values ( ), based on the assumption that dt is t-independent, is illustrated by the insets in fig. . in this small-rs range, our results are in a good agree- ment with the earlier data by smith and stiles [ ], and by pan et al. [ ]. the assumption of temperature independent dt , however, becomes dubious at low densities (high sr ), where the resistance varies significantly over the studied temperature range; in this case, the two parameters dt and *m become progressively more correlated. the open dots in fig. ,b were obtained by assuming that dt is t-in- dependent over the whole explored range of n : *m in- creases with sr , and the ratio * / bm m becomes . ∼ at = sr ( = . bm is the band mass). as another limiting case, one can attribute the change in ( )tρ solely to the temperature dependence of the short-range scattering and request ( / )d dt ∝ τ to be proportional to ( )( / )tρ ∝ τ . in the latter case, the extracted dependence * ( )sm r is weaker (the solid dots in fig. ,b). our data shows that the combination *( )dt t m+ is al- most the same for electrons in both spin-up and spin-down subbands (e.g., for = . · n cm – and = . h t ( = %p ), the dt values for spin-up and spin-down le- vels differ by %≤ ). this is demonstrated by the observed almost % modulation of sdh oscillations (see, e.g., figs. ,a and ,b). thus, the carriers in the spin-up and spin-down subbands have nearly the same scattering time. . . comparison with other data . . . high density/weak interaction regime. as seen from fig. , the data on n-channel si-mos samples are in a reasonable agreement with the data obtained by zhu et al. [ ] for n-type gaas/algaas samples from mea- surements of sdh effect in tilted magnetic field. because of a smaller (by a factor of ) electron effective mass in fig. . shubnikov–de haas oscillations versus h⊥ for n = . · = cm– (i.e. = . sr ) and = . t ; . ; . ; . ; . k: = h (a) and . t (b). the insets show the temperature de- pendences of fitting parameters *( )dt t m+ . a b h = || h = . t|| h , t� r , k � � r , k � � . . t, k t, k . . . . . . . . . . . . . . . k . k . k . k . . m* = . m* = . t = . kd t = . kd (t + t )m * d (t + t )m * d fig. . parameters * *g m , *m , and *g for different samples as a function of sr (dots). the solid line in fig. ,a shows the data from ref. . the solid and open dots in figs. ,b and ,c corres- pond to two different methods of finding *m (see the text). the solid and dashed lines in fig. ,b are polynomial fits for the two dependences * ( )sm r . the values of *g shown in fig. ,c were obtained by dividing the * *g m data by the smooth approxima- tions of the experimental dependences * ( )sm r shown in fig. ,b. . . . . g * m * / m b m * /m b g * a b c rs david shoenberg and the beauty of quantum oscillations fizika nizkikh temperatur, , v. , no. gaas, similar sr values have been realized for the electron density times lower than in si-mos samples. the width of the confining potential well in such gaas/algaas heterojunctions is greater by a factor of than in ( ) si-mos, due to a smaller mass zm , lower electron densi- ty, and higher dielectric constant. this significant differ- ence in the thickness of d layers may be one of the rea- sons for the % difference between the χ*-data in n-gaas and n-si-mos samples seen in fig. ; at the same time, the minor difference indicates that the effect of the width of the potential well on renormalization of *χ is not dramatic. the sdh experiments provide direct measurement of *χ in weak perpendicular and in-plane magnetic fields c feω , * totb fg h eμ [ ]. under such condi- tions, the quantum oscillations of the fermi energy may be neglected, and, in the clean system, the magnetization should remain a linear function of h , ** tot ( )hχ ≈ χ . also, under such experimental conditions, the filling factor is large, = / ( ) nh eb⊥ν and the amplitude of oscilla- tions is small | | / xx xxδρ ρ . figure shows, on the h⊥ρ− plane, the domain of the weak magnetic fields, > ν , where the sdh oscillations have been measured in refs. , . as the perpendicular magnetic field increases further (and ν decreases), the sdh oscillations at high density cn n transform into the quantum hall effect; for low densities, cn n≈ , the sdh oscillations transform into the so-called «reentrant qhe–insulator» (qhe–i) transi- tions [ ]. the uppermost curve (open circles) presents the ( )hρ variations in the regime of the qhe–i transitions [ ], measured for a density slightly larger (by %) than the critical density value cn for the metal–insulator transi- tion. this diagram is only qualitative, because the cn value is sample (disorder)-dependent. . . . low density/strong interaction regime. in the vi- cinity of the critical density cn n≈ , the number of ob- served oscillations decreases, their period increases, and the interpretation of the interference pattern becomes more difficult, thus limiting the range of direct measurements of * ( )srχ . the horizontal bars in fig. are obtained from considera- tion of the sign and period of sdh oscillations [ ] as ex- plained below. they show the upper limit for *χ , calculated from the data reported in refs. , , . figure ,b demon- strates that in the density range – – . cm < < · cmn , the oscillatory xxρ (beyond the magnetic field enhanced = ν valley gap) has minima at filling factors = ( ), = , , ...,i iν − ( ) rather than at = iν (in ( ) si-mosfets, the valley degeneracy = gν ). the latter situation is typical for high densities and points to the inequality ** < / b cg bμ ω . in other words, the sign of oscillations at low densities is reversed. this fact is fully consistent with other observa- tions (see, e.g., fig. of ref. , fig. of ref. , and fig. . renormalized spin susceptibility measured by sdh effect in tilted or crossed fields on n-si-mos by okamoto et al. [ ], pudalov et al. [ ], and on n-gaas/algaas by zhu et al. [ ]. horizontal bars depict the upper and lower limits on the *χ values, determined from the sign of sdh oscillations, measured at = . mkt in ref. . dashed and dotted lines show two examples of extrapolation of the data [ ]. [ ] [ ] [ ] rs * / b fig. . (a) overall view of the sdh oscillations in low fields at different densities. empty circles show the xxρ oscillations for high-mobility si-mosfet sample in high fields, corresponding to the reentrant qhe–insulator transitions [ ]. (b) expanded view of one of the ( )xx hρ curves ( = . · n cm– (right axis) and its oscillatory component normalized by ( )a h (left axis)) [ ]. dashed line confines the region of the sdh measure- ments in refs. , . n = . . . . . . . . . . . . . . a b in su la to r in su la to r q h e q h e . . . . – . . . . . h, t � � � /( a ) � /( h /e ) � /( h /e ) / = eh/(nh)� � = v.m. pudalov fizika nizkikh temperatur, , v. , no. figs. – of ref. ). as fig. shows, the ratio * / bχ χ exceeds / = . bm at sr ≈ ; the first harmonic of os- cillations disappears at this density (so-called «spin-zero»), and the oscillations change sign for lower densities. the sign of the sdh oscillations is determined by the ratio of the zeeman to cyclotron splitting [ , ] * * * cos cos ,b b bc g h m ⎛ ⎞ ⎛ ⎞μ χ π ≡ π⎜ ⎟ ⎜ ⎟⎜ ⎟⎜ ⎟ χω ⎝ ⎠⎝ ⎠ ( ) therefore, we concluded in ref. that, in order to have negative sign in the range > > sr , the spin susceptibil- ity *χ must obey the following inequality: * . = < < = . . b b bm m χ χ ( ) thus, eqs. ( ) and ( ) enable us to set the upper and lower limits for *,χ which are shown by horizontal bars in fig. at = . – . .sr as density decreases (and sr in- creases), due to finite perpendicular fields, in which the sdh oscillations were measured, the condition of eq. ( ) becomes a bit more restrictive, which leads to narrowing the interval between the upper and lower bars [ ]. . magnetooscillations in strongly interacting d electron system in sec. . above we used the semiclassical lk formu- la for noninteracting d case [ ] and have made only transparent changes for the d electron spectrum [ ]. we assumed that for the interacting system, the lk-formula remains applicable, when bare (band) quasiparticle para- meters are replaced with their values renormalized by inte- raction. this assumption is examined in this section. we shall consider only the case of weak oscillations when they are exponentially damped by either disorder broadening of the landau levels or temperature smearing of the fermi energy. for simplicity, we call this the «low-magnetic field regime». in higher quantizing fields, deviations from the lk formula were found earlier [ , , ] and attributed to the magnetic field dependent oscillatory renormalization of the effective g-factor and mass, due to the inter-landau level interaction [ ]. magnetooscillations in the interacting d system were studied theoretically over the last years. the main issue under investigation is whether the oscillations frequency, phase, and damping factor for the strong interaction case remain the same as in the noninteracting system eq. ( ) and whether the fl parameters in the lk formula can be taken at zero magnetic field. bychkov and gorkov [ ] have found that the amplitude of oscillations eq. ( ), rather than their frequency, is renormalized by interaction. fow- ler and prange [ ] and engelsberg [ ] showed that the electron–phonon scattering rate does not appear in the os- cillations amplitude; martin et al. [ ] have shown that the inelastic electron–electron scattering does not contribute to the damping of magnetooscillations. recently, an important advancement has been made in theory [ , ] of magnetooscillations. it was shown that the lk formula, in general, is still applicable when the os- cillations are exponentially small. however, due to the in- terference between electron–electron and electron–impur- ity interactions, damping factor in oscillations acquires an additional term in both the diffusive and ballistic regimes as follows [ ]: [ ] *ln ( , ) = ( ) ( ), de b eh a t h t t t m m ck ⊥ ⊥− + − α π ( ) where ** * * * * ( ) = ,dd d m m t t t m m ⎛ ⎞δτδ δ α − − −⎜ ⎟ ⎜ ⎟τ⎝ ⎠ * * ( ) = ln f em t tm δ ⎛ ⎞ − ⎜ ⎟ ⎝ ⎠ a , * * = ln ,d f d e t t δτ ⎡ ⎤⎛ ⎞ π τ−⎢ ⎥⎜ ⎟ ⎝ ⎠τ ⎣ ⎦ a = , a a d f f ⎛ ⎞ +⎜ ⎟ ⎜ ⎟+ π σ⎝ ⎠ a ( ) and the factor in the last line is the number of triplet terms for a system with two degenerate valleys. our numerical simulations show that within the relevant interval = . – . t k and sr ≤ , the ln t terms in eq. ( ) can be replaced with a t-independent constant. by combining the lk result eq. ( ) with the interaction-induc- ed corrections and replacing all ln t terms by a constant within our limited t range, we obtain the following linea- rized equation [ ] in the ballistic regime for the short- range scattering (i.e. trdτ ≈ τ ): [ ] *ln ( , ) = ( ) de b eh a t h t t t m m ck ⊥ ⊥− + + π τ = π a ( ) = d d t t t ⎛ ⎞δσ + −⎜ ⎟ σ⎝ ⎠ . ( ) this remarkable result means that the t-dependent cor- rection to the dingle temperature, ( ) /d dt t tδ is just one- half of the interaction correction to the conductivity [ ] ( ) / dtδσ σ . the factor / originates from the difference between the interaction corrections to the momentum re- laxation time ( tr ( )tδτ ) and quantum scattering time [ ] ( ( )d tδτ ). we note that the empirical procedure used for finding *m in our earlier paper (ref. ) was based on the assumption that [ ]* = ( ) / ,d d dt t t−δσ σ which differs from eq. ( ) by a factor of / . for the interacting case, eq. ( ), the linear t-de- pendence of ln ( , )a t h⊥ holds to the first approximation. this is in agreement with our experiments [ ] which david shoenberg and the beauty of quantum oscillations fizika nizkikh temperatur, , v. , no. show that ln ( , )a t h⊥ for high sr varies linearly with temperature within the experimental range = . – kt (see the inserts to fig. ). . . refinement of the extracted af values at relatively high densities (which correspond to < )sr , the corrections to the lk result are insignificant within the studied t range. as sr increases, the tempera- ture dependences of the oscillation magnitude predicted by the lk theory eq. ( ) and the interaction theory eq. ( ) start deviating from each other. the values of | | af ex- tracted from sdh data using eq. ( ) are smaller than those obtained with the lk theory but larger than | | af obtained with the empirical procedure used in ref. . e.g., at = . sr , the af values obtained according to eq. ( ) and the empirical procedure of ref. are – . and – . , respectively. in ref. we have reanalyzed the data of ref. using eq. ( ) and compared them with available results from other transport measurements. the af values obtained in ref. from the analysis of sdh oscillations using the theories [ , ] (see sec. ) are plotted in fig. . for comparison, we have also plotted the af values calculated in ref. from fitting the mono- tonic temperature and magnetic field dependences of the conductivity ( )tΔσ and ( )hΔσ [ , , ] with the theory [ ]. there is a good agreement between all data. the spin susceptibility * * *g mχ ∝ obtained from sdh measurements appears to be almost t-independent [ ], in apparent disagreement with the interaction correction the- ory [ ] and renormalization group (rg) theory [ ]. this contradiction could be resolved, provided the t-depen- dence of *g is exactly compensated by the opposite t-de- pendence of *m , so that * * *g mχ ∝ remains almost con- stant. the compensation, however, seems rather unlikely. we believe that the absence of temperature dependence in * *g m values from sdh is simply a consequence of the cut- off that is imposed by finite magnetic fields *tot > / bh kt g μ which are applied in sdh measurements. . . other quasiparticle parameters extracted from sdh data . . . valley splitting. the analysis of sdh oscillations using eq. ( ) also allowed us to estimate the value of the energy splitting [ ] vΔ between two valleys in the ( )- si-mosfet samples. a nonzero valley splitting causes beating of sdh oscillations. figures ,a and b show the sdh oscillations for two different samples. the electron densities are . · and · cm– , respectively. the amplitude of weak sdh oscillations normalized by the first harmonic a is expected to be field independent if = .vΔ a noticeable reduction in the sdh amplitude observed for both samples at small fields can be attributed to a finite valley splitting. although the node of sdh oscillations expected at . th⊥ ≈ cannot be resolved for samples with mobilities ∼ m /(v·s), vΔ can still be estimated from fitting of the h⊥ -dependence of the sdh amplitude with eq. ( ) modified for the case of a finite vΔ : = . vΔ k for sample si - and . k for si - . this estimate provides the upper limit for vΔ at = h⊥ : in nonzero h⊥ fields, vΔ may be enhanced by the interlevel interaction effects [ , , ]. . . . drude scattering time. the momentum relaxa- tion time τ needed for calculating the interaction correc- tions was determined from the drude conductivity =dσ = e / ;b en m mτ the latter was found by extrapolating the quasi-linear ( )tσ dependence observed in the ballistic regime to = t [ , ]. note that in order to extract τ from the drude conductivity, one should use the bare bm rather than the renormalized effective mass: according to the kohn theorem, the response of a translationally-in- variant system to the electromagnetic field is described by bm in the presence of electron–electron interactions; this result also holds for weak disorder ( fe τ ). it is worth mentioning that several prior publications [ , , ] incor- rectly used *m instead of bm to estimate τ from dσ ; as a b – . – . – . – . – . – . – . – . – . – . – . f s f s rs fig. . (a) the dashed curve corresponds to ( ) a sf r extracted from the sdh data [ ] using the lk theory, the dash-dotted curve — to the empirical approach used in ref. . the symbols depict af values obtained from fitting the transport data with the theory [ ]. the shaded regions in panels (a) and (b) show the ( ) a sf r dependence (with the experimental uncertainty) ob- tained from fitting our sdh data [ ] with the theory [ ]. (b) comparison of af values recalculated from available ( , = )t hδσ data: dots — ref. , triangles and diamonds — refs. and , respectively. v.m. pudalov fizika nizkikh temperatur, , v. , no. shown in ref. , this affects the value of the fitting para- meters extracted from comparison with the theory [ ]. the textbook value [ ] for the light electron mass in bulk si is ( ) . dbm ≈ . for inversion layers on ( ) si- surface [ ], ( ) = ( . – . ) . dbm ± was found from tunneling measurements. the * ( )m n data obtained from the analysis of sdh oscillations over a wide range of densi- ties = . – . sr [ ], can be fitted with a polynomial * ( ) = . ( . . )s s sm r r r+ + . these *m data ag- ree well with earlier values of *m extracted from sdh oscil- lations [ , , , ] in narrower ranges of densities. by extrapolating the polynomial * ( )sm r to = sr we obtain ( ) = . . dbm ± ; following ref. we adopted this value throughout the paper. . conclusion david shoenberg was a great master in experimental low-temperature physics. besides the de haas–van alphen effect, he has made substantial contribution to understand- ing of the magnetic properties of superconductors. his book «superconductivity» written in moscow in is one of the reference books on my bookshelf and is used as a textbook by russian students. shoenberg's experiments on studying quantum oscillations in metals and the fine experimental techniques developed by him for this re- search represent a piece of experimental art. david shoen- berg has shown how the properties of interacting systems can be revealed by measuring quantum oscillations under nonlinear conditions imposed by interactions. in line with this approach, we performed studies of the shubnikov–de haas effect for strongly interacting two-di- mensional system of electrons. from the amplitude of quantum oscillations, we determined the interaction-induc- ed renormalization of the quasiparticle parameters, such as the effective mass, spin susceptibility, and g-factor. the fermi-liquid interaction parameter ( ) af n obtained from the analysis of sdh oscillations agrees well with the ( ) af n values obtained by fitting the monotonic transport data with the interaction correction theory [ ]. however, it remains so far unclear how to reconcile the af values obtained at low electron densities from fitting the ( )tσ and sdh data (by using the interaction correction theory) with the corresponding values [ – ] obtained by fitting the ( , )t hσ data with the rg theory. possibly, for a quantitative description of the interaction effects in low temperature transport, the rg theory should be extended to a more realistic case of a finite intervalley scattering rate and to higher orders. . acknowledgments the author benefited from fruitful collaboration with m. gershenson, h. kojima, e.m. dizhur, g. bauer, g. brun- thaler, o.e. omel'yanovskii, n.n. klimov, d.a. knyazev, a.yu. kuntsevich in performing measurements. the work was partially supported by grants from rfbr, russian acad- emy of sciences, and russian ministry for education and science (under contracts nos. . . . , . . . , p , p , p ). . d. shoenberg and j. vanderkoy, j. low temp. phys. , ( ). . d. shoenberg, canad. j. phys. , ( ); d. shoen- berg and i.m. templeton, ibid. , ( ). . r.b. dingle, proc. roy. soc. a , ( ). fig. . sdh oscillations normalized by a : (a) sample si - , = . · n cm– , = t mk; (b) sample si - , = · n cm– , = t mk. dots show the data, solid curves — the theoretical dependences eq. ( ) modified for a finite = . vΔ and . k for samples si - and si - , respectively. panels (c) and (d) show the t-dependences of the sdh oscillations amplitude for si - ( = . · n cm– ) and si - ( = · n cm– ), solid curves — the noninteracting lk-model eq. ( ), dashed curves — the fit based on the interaction theory eqs. 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complexity theory can be used to specify constraints on mental representations abstractly formulated as vectors in a high-dimensional space. a central feature of the proposed model is that perfect form depends both on features of the objects or events perceived and on the nature of the encoding strategies or model of the observer. a simple example illustrates the proposed calculations. a number of interesting implications that arise as a consequence of reformulating beauty in this way are noted. »können sie mir sagen, was schönheit sei? « rief er aus. »vielleicht nicht!« versetzte ich, »aber ich kann es ihnen zeigen.« »…….daß die schönheit etwas unbegreifliches….sei. was man nicht begreifen kann, das ist nicht, was man mit worten nicht klarmachen kann, das ist unsinn.« johann wolfgang goethe  der sammler und die seinigen aesthetics has been a human concern throughout history. cognitive science is a relatively new development and its implications for a theory of aesthetics have been largely unexplored. what would a cognitive theory of aesthetics look like? can cognitive science provide a framework for the analysis of beauty, does our knowledge about cognition provide insights into the what and why of beauty? or must it remain inconceivable? almost everything can be beautiful to someone, at some time. kant noted that judgments of beauty are sensory, emotional, and intellectual all at once (kant, ). he is surely right. nevertheless, that is an unacceptable starting point for a theory of aesthetics, because it leads inexorably to this quote from wikipedia: “thus aesthetic judgments might be seen to be based on the senses, emotions, intellectual opinions, will, desires, culture, preferences, values, subconscious behavior, conscious decision, training, instinct, sociological institutions, or some »can you tell me what is beauty?« he exclaimed. »perhaps not!« i replied, »but i can show it to you. ……beauty is something inconceivable….what one cannot conceive of is nothing, what one cannot explain with words is nonsense.« complex combination of these, depending on exactly which theory one employs”. in other words, beauty is hopelessly complex. if one accepts this conclusion, a theory of aesthetics is impossible. the meaning of the word “beautiful” has become so over-extended in everyday discourse that it is no longer useful as a theoretic construct. therefore, the scope of a theory of aesthetics must be restricted somehow. schopenhauer did so by drawing a strict line, perhaps an illusory one but a useful one, between the world of the intellect and the world of the will (schopenhauer, ). aesthetics is located in the world of the intellect, far removed from the world of the will. beauty is the contemplation of perfect form that has nothing to do with utility or personal and societal values. the contemplation of perfect form is the purest activity in the world of the intellect. thus, following schopenhauer, one might suggest that a theory of aesthetics should be concerned with explicating the notion of perfect form. of course, such a theory by itself could not provide a complete account of aesthetic judgments, which are influenced by just about everything and, as i have argued above, represent a too difficult and messy problem for theoretical analysis. thus, my goal here will be to clarify the notion of perfect form. but as i shall show below, this will also help us to understand the role of observer related factors in the perception of beauty, and thus bring us closer to a fuller understanding of the features of mental representations related to the experience of beauty. these then would constitute the universal basis that kant argues underlies judgments of beauty – including the beauty of a rose in the garden, a towering mountain, a piano sonata, a tennis serve, and of a mathematical proof. what is it that can make these objects and events beautiful? before continuing, a remark on art and beauty seems in order. much of art, especially modern art, strenuously avoids being beautiful. to quote a recent newspaper article: is beauty dead? the answer that springs from much of contemporary art is an unapologetic "yes." … today, beauty is no longer about what's pretty, symmetrical, or harmonious. it's about what stirs the viewer to grapple with the world as it really is. emotional and intellectual impact are the criteria by which modern art is judged, rather than beauty. the article goes on to argue for a new conception of beauty, one that allows us to appreciate the “beauty of ugliness.” instead, i want to retain the traditional meaning of beauty, that is, to reserve the concept of beauty for “what is pretty, symmetrical, and harmonious.” i shall not be concerned with the questions what the proper role of beauty is or should be in art. mental representations beauty is in the eye of the beholder. another way of saying that is that beauty is not a property of objects but of their mental representations created by the mind/brain. to experience an object as beautiful, it must possess certain affordances and it must be appreciated properly by someone. the objective and the subjective must mesh in just the right way to yield the experience of beauty. only some objects afford mental representations that some of us experience as beautiful. what are the properties of an object so that it can be perceived as beautiful? what allows one person to experience beauty where another remains unmoved? c. strickland, christian science monitor, - - the mind/brain represents objects as activity patterns in an (intricately structured) cloud of neurons, or, more abstractly, as vectors in a high-dimensional space. mental processes are manipulations of these representations, namely, computation. thus, an object d is represented by a vector in n-dimensions, d = {d , d , d ,…..dn}. one could think of di as the activation value of a specific neuron, in which case the dimensionality of d would be extremely large; millions of neurons may be involved in mental representations. however, since each neuron is attuned to only a few aspects of the input it receives (neurons perform dimension reduction), the actual dimensionality of mental representations is much lower. it can be thought of as the set of independent quantities needed to specify d. to describe d, we can either enumerate all its elements or specify a computer program that generates the set of elements. specifying d via the computer program that generates it makes it possible to measure its complexity – specifically, its kolmogorov complexity. kolmogorov ( ) defined complexity as the shortest code in a universal programming language. he showed that the length of the shortest description of an object x is invariant up to a constant between different universal languages, which makes kolmogorov complexity a very useful construct. the kolmogorov complexity of an object x is denoted as k(x). the conditional kolmogorov complexity k(y|x) is the length of the shortest program that yields y, given x as an input. mental representations are not static: they can suffer interference, they may decay in time, and they are subject to consolidation as well as active, controlled re-coding under conscious control. thus, an object such as a painting may have an embodied, perceptual representation, which in itself may be complex, consisting of a perceptual record combined with later experiences and memory images. abstractions of this embodied representation may be created, often involving verbal and symbolic recoding, compressing the original vector representation and thereby reducing its information content. in reading a text, we distinguish the mental representation of the text itself – the textbase – and its knowledge and interest-based elaboration – the situation model (kintsch, ). this elaboration can be automatic, as when experts fill in the gaps and links in a text within their domain of expertise, but it also is often conscious and indeed effortful, as when we labor to understand a difficult text in an unfamiliar domain. this labor is not confined to the initial reading but may continue as we ruminate about the implications of what we have read. thus, memory traces are dynamic, with important consequences for the perception of beauty. it is important, especially when we are concerned with the subjective experience of beauty, to emphasize that the processes that contribute to the vector d comprise the total human response to a beautiful object – sensory, conceptual, emotional. imagine standing on a mountain top, contemplating the beautiful scenery below. the mental representation of that event is not just visual, but emotional (the euphoria of having reached the summit), and embodied (the fatigue of the ascent). cognition does not occur in a disembodied mind, but in an acting, feeling, perceiving person. the awe with which we respond to a certain piece of music is as much a part of our mental representation as the pattern of sounds we perceive. the happiness we experience looking at some picture becomes an integral part of its mental representation. emotions and bodily events are represented in our brains as patterns of neural activity, as are visual scenes or the semantic content of a story. the vector d is all brain activity, but this activity is the result of multimodal processes, ranging from the embodied to the symbolic. mental representations are physical symbol systems, realized as patterns of activation over sets of neurons in the brain. describing a mental representation is to specify the probability distribution of activation values. hence, for present purposes, kolmogorov complexity can be given an information theoretic interpretation. let x be a set of neurons {x} with a probability distribution p(x). the kolmogorov complexity k(x) can be estimated by its entropy h(x) = ex [i(x)] = - ∑ p(x) log p(x). xεx let q(x) be a different probability distribution over x. the conditional kolmogorov complexity k(xp|xq) can be equated with the kullback-leibler divergence – the average number of additional bits per datum necessary to transform xp into xq : divkl(p(x)q(x) = ∑ p(x) log(p(x)/q(x)) ( ) xεx the vector d is the result of perceptual and conceptual processes in the human mind/brain. in the same situation, different brains will construct different representations. (trivially, the representation of a red apple will be different for a color-blind person and one with normal color perception). moreover, in the same situation, the same person at different times may construct different representations, depending on the person’s momentary goals, motivation, available knowledge, and so on. (the tiger admired in the zoo and the one ready to attack in the jungle.) hence d, for a given object, depends on the conditions of encoding, or the model m used for encoding. thus, i take mental representation to consist of an object (event, performance) with properties d (for data) and an encoding procedure m (for model, or method), {dm}. what is there about d so that, for an appropriate m, it is perceived as beautiful? what sort of models m can result in encodings that we experience as beautiful? all mental representations, beautiful or not, are subject to a general constraint that has been called the simplicity principle (chater, ; chater & brown, ). the simplicity principle was first espoused by mach ( ), who suggested that the cognitive system prefers patterns that provide simple descriptions of the data. a number of psychological observations supported mach’s conjecture, most notably the gestalt theorists’ law of prägnanz (koffka, ; other examples are cited in chater & vitanyi, ). simplicity is related to redundancy, as simon pointed out: if no aspect of a complex system “can be inferred from any other then it is its own simplest description. we can exhibit it, but we cannot describe it by a simpler structure” (simon, , p. ). in a loose way, the idea that the cognitive system prefers a simple, non- redundant code also relates to the observation that people tend to remember the gist of a text, rather than all its detail. the macropropositions in a text provide an efficient code from which some of the rest of the text can be reconstructed by a reader familiar with the domain. in its modern form the simplicity principle states that the cognitive system tends to minimize the kolmogorov complexity k(x). the simplicity principle is closely related to a probabilistic bayesian analysis. there are two results that are particularly useful for present purposes (more detail see also chater & brown ( ) and schmidhuber ( ) and proofs are given by vitanyi and li, , and chater and brown, ). first, a probabilistic analysis suggests that the cognitive system favors an m such that p(m|d) is maximized. thus, it can be shown that there exists a close relationship between complexity and probability max p(m|d) = min {k(m) + k(d|m)}. the model m that has the highest a priori probability is the model that has the shortest code for the data. that code is a two-part description, involving a specification of the model m and an encoding of the data, given m. secondly, complexity theory can be extended to the situation where data accumulate over the course of time. predictions of the next item based on simplicity and predictions based on the item’s probability are equivalent. the relevance of kolmogorov complexity for the analysis of beauty was first recognized by schmidhuber ( ) in his discussion of low- complexity art. he notes that the observer’s model (schmidhuber uses the term coding algorithm) embodies the observer’s subjectivity, and argues that, given the model, the most beautiful drawing among a set of drawings classified as comparable by a given subjective observer is the one for which the information to compute the model from the data is minimized. the kolmogorov complexity theory is defined for universal programming languages. the human mind is no turing machine, however. in terms of the chomsky hierarchy of formal languages, the mind is at the level of a context sensitive language (miller & chomsky, ). that means that we cannot compute kolmogorov complexity unless we know just what the constraints are that are imposed by the human cognitive system. in general, we do not know what form mental representations take, what sort of coding mechanisms are possible. the problem, then, is that the kolmogorov complexity and the complexity that humans experience do not always correspond. for instance, the transformation  is exceedingly simple, but it may not be immediately obvious. the pattern in tthttthhth… appears complex to us, but, as the parity of the digits of π, it is trivial to generate for a computer (griffiths & tenenbaum, ). such problems limit the applicability of complexity theory, but as a general framework it can still be useful, and, as demonstrated below, when we can make precise assumptions about the form of mental representations, complexity computations may be computationally tractable. to use complexity theory as a basis for a cognitive theory we must, therefore, identify the constraints imposed by the human cognitive system with respect to the perception of beauty, or perfect form. psychology today is far from being able to do so in a comprehensive and definitive manner. nevertheless, there are some results that permit us to formulate a provisional answer. i have already mentioned a general constraint that all mental representations are subject to: the tendency to prefer the simplest possible code for the data. this suggests the hypothesis that beauty is related to the notion of a good gestalt: if an object can be coded so as to result in a good gestalt, we may perceive it as beautiful. gestalt psychologists (e.g. koffka, ) have specified the notion of “good gestalt” in some detail. basically, it amounts to a whole whose various parts or aspects fit together in a harmonious way. below, i shall try to specify further the notion of harmony in terms of complexity theory. harmony, however, is not enough. there are two more classic results from psychology that need to be taken into account. one says that we need variety, the other that there can be too much variety. any stimulus that is presented for a long time or repeatedly will evoke a progressively weaker neural response. importantly, this is not only true for perception, but also for emotion: affective habituation is very much like sensory adaptation, as titchner ( ) had already noted. thus, adaptation is a basic property of the cognitive system that must be counteracted. to be perceived as perfect form, a stimulus must afford the possibility for varied and dynamic encodings. a too simple object quickly becomes boring. the same activity, however blissful it may be initially, loses its ability to please when mindlessly repeated – variety, as they say, is the spice of life, and of beauty, too. variety is needed, but within limits. what the limits on complexity are varies greatly with the nature of the perceptual stimulus (through chunking) and the level of domain expertise of the perceiver. human consciousness or working memory has a limited capacity. what can be apperceived is limited in complexity. wundt ( ) and miller ( ) have shown that the number of elementary stimuli that can be simultaneously perceived is limited, although that limit can be expanded through the process of chunking. chunking is a process of grouping whereby the group functions as a unit. furthermore, with training, people can form retrieval structures that make available large amounts of relevant information in working memory (the long-term working memory of ericsson & kintsch, ). the relationship between a whole and its parts is fundamental to the notion of beauty discussed below. concept such as part and aspect are, of course, perfectly good commonsense terms, but we must take note of some important research results. parts (nose and eyes are parts of the face) or aspects (the color, texture, or orientation of an object) can be defined physically as well as psychologically, but the two do not always correspond. this is shown most clearly by research that has used discrete static stimuli that vary along several dimensions. when subjects are supposed to pay attention to one dimension or aspect, they sometimes experience interference from variations in an irrelevant dimension. this happens, for instance, when subjects are asked to evaluate the brightness of a stimulus and an irrelevant aspect such as saturation is varied at the same time. aspects that interfere with each other are called “integral dimension” whereas aspects that do not interfere with each other (the size of an object does not interfere with brightness judgments) are called “separable dimensions” (garner, ). integral dimensions are perceived holistically, that is, people cannot selectively attend to one dimension. thus, a physical analysis of a stimulus and a psychological analysis do not always coincide: physically there are two aspects, but psychologically there is only one. the parts of objects can be defined in different ways, for example by means of the geons of biederman ( ), which are a set of basic shapes that can be used to represent a large number of objects. objects, of course, are rarely perceived alone but as part of a visual scene. visual scene analysis (e.g. rensink, ) distinguishes between the gist of a scene (a mountain landscape), its parts (a mountain peak, a lake) and the relation among the parts (the lake is below mountain and to the left). the process is bidirectional and iterative. gist is recognized by invoking one of the scene schemata stored in long-term memory on the basis of just a few recognized objects. the gist then participates in identifying further objects and modifying existing ones. the spatial layout is used to check the emerging perceptual representation. in turn, the new data refine or change the gist representation, with the interplay of bottom-up and top- down processes continuing until a stable perceptual representation results. stimuli that evolve over time, as in listening to music or reading a book, contain cues that alert the perceiver to their part-whole structure. the chapter - and paragraph - organization of a book serves as an obvious guide to the reader, but there are many other cues to help the reader (kintsch, ). the reader forms a macrostructure (the gist) on the basis of some key propositions, then uses it to construct a detailed representation of the text, including the intricate relationships among propositions. text representations, both macro- and microstructure, evolve over time and, if the reader expends the required cognitive effort, are constantly being modified as new aspects are being noted. two important points have to be made about the recognition of whole objects and their parts. first, it is hierarchical. what is a part at one level of analysis may be the whole at a more fine grained level. this is the case for reading or listening to music as well as visual scene analysis. second, less obviously, the process is dynamic. the limited capacity of working memory prohibits the simultaneous recognition of all parts of an object. only a limited amount of information can be held in working memory when reading a book or listening to music. similarly, it is in general impossible to perceive more than two or three parts or aspects of an object or scene at a time, and a shift of attention is required to focus on other parts, or for a more detailed analysis. thus, a whole series of ephemeral structures must be built up in working memory before a detailed, stable percept is obtained. similarly for reading: text comprehension and a stable text memory are generated via temporary structures in working memory, roughly corresponding to sentence interpretations. this process can be automatic, as when experts are working in their domain of expertise, but in general requires a certain amount of cognitive effort. if that effort is not forthcoming, perception and comprehension may remain deficient. perfect form historically, the role of harmony and the prevention of habituation effects has been recognized by writers who sought to define beauty. theorists of aesthetics have provided a number of feature lists that they claim characterize beauty. one such list by the painter william hogarth i find particularly instructive. hogarth ( ) lists six principles, as cited in wikepedia: ( ) harmony, or fitness of the parts to the whole; ( ) variety; ( ) uniformity, regularity or symmetry, which must be in the service of fitness; ( ) simplicity or distinctness, which enables the viewer to appreciate the variety; ( ) intricacy, which allows for active processing, leading the eye "a wanton kind of chase”; ( ) quantity or magnitude, which attracts attention and produces admiration and awe. of these ( ) is really subordinate to ( ) – fitness can be based on uniformity, regularity or symmetry – and ( ) is subordinate to ( ) - variety must be perceptible, simple and clear, rather than chaotic or random; variety must not interfere with fitness. ( ) seems rather like a special case – significant as far as beauty is concerned, but not a necessary characteristic of harmony; i shall disregard it. that leaves us with just three criteria: (a) fitness, (b) variety and (c) active energy. harmony is required of the various aspects of a beautiful object or event. but by itself it does not guarantee beauty: the four sides of a square score high on harmony, but that does not make the square beautiful. the parts of a beautiful object, though harmonious, should also be varied and distinct. finally, beauty requires an object that affords the active participation of an observer. a beautiful object is interesting, in the sense that an observer can find ever new ways to admire it; it “allows for active energies,” hogarth said. for comparison, here is a modern list of the “path to beauty,” by ramachandran and hirstein ( ): . extremes: exaggeration along some dimension relative to mean . structural goodness: good gestalt . unidimensionality: standing out in a single dimension . contrast: strong features emerge prior to grouping . challenge: requirement to engage in perceptual problem solving . genericity: avoids statistically suspicious coincidences . metaphoricity: hidden connection between different parts or aspects . symmetry this list maps quite well into hogarth’s list: structural goodness and symmetry are what he called “fitness”; challenge and metaphoricity belong to the “active energy” category; and the other criteria have to do with “variety.” however, the ramachandran and hirstein list is not much of an improvement over hogarth: symmetry ( ) is clearly redundant, since it is part of a good gestalt ( ); metaphoricity ( ) is equally redundant, since it is just a particular kind of challenge ( ) – finding hidden connections is perceptual problem solving. the other criteria specify how variety can be achieved: ( ) and ( ) imply that the most successful variety involves exaggeration along a single perceptual dimension; ( ) and ( ) are related to the simplicity and distinctiveness principle of hogarth: ( ) excludes randomness and arbitrariness, and ( ) says there should be distinct parts (which then can be grouped into a whole). edelman ( ) has a chapter on “beauty” where he discusses the ramachandran and hirstein principles ( ), symmetry, and ( ), exaggeration. he credits the english painter reynolds ( - ), the first president of the royal academy, with an algorithm for distilling “perfect beauty”: averaging over many instances that may not be very beautiful in themselves, which irons out the imperfections of particular instances and yields an idealized image. data from face perception experiments are cited in which synthetic faces are judged beautiful the more common a face is (the larger the number of instances blended into it). the most common face – the average – is the most harmonious one, because, by definition, it retains the essential features of what makes a face, but has lost individual imperfections. thus, the reynolds/edelman algorithm can be viewed as an application of hogarth’s harmony criterion. there are innumerable other lists in the literature which seek to specify the conditions for beauty, but to examine them would be a waste of time. making more lists and citing more examples is not going to get us anywhere. we know, roughly, what stimuli are perceived as beautiful. we need to specify what that means for their mental representations - how beauty is computed by the mind. the kolmogorov theory of complexity can help us arrive at a more principled analysis of beauty. however, for a critical review of this work, see schmidhuber ( ) as has already been mentioned, schmidhuber ( ) pioneered this approach. he distinguished between an observer’s subjective encoding scheme, the model, and the data, and argued that beauty in a certain type of art can be identified with low kolmogorov complexity. here, a more differentiated analysis will be presented, involving multiple criteria and framed within the part-whole distinction. the discussion will be motivated both by results from the literature on aesthetics and considerations about the nature of mental representations from cognitive science. according to the literature reviewed above, beauty has to do with the relation of an object to its parts and the relations among its parts, as encoded by a human observer. formally, we have represented the mental representation of an object by a vector d of n dimensions, d = {d , d , d ,…..dn}. an aspect ai is similarly represented by a vector ai = { a i, a i, a i,…..ai ni}. if d has k aspects, its representation is the kth-rank tensor, d = a ⊗a ⊗…..⊗ak. for computational simplicity, this could be approximated in a variety of ways, for example, through circular convolution or simply by taking the average, d = Σkai. i assume that the parts (or aspects) of an object d are a property of the object d as it exists independently of human observers. what concerns us here is how these aspects are encoded by a human observer, that is, not the aspect ai itself but how it is encoded by some model, aimj. in general, an object may have aspects that a given observer does not encode at all, or that different observers (or the same observer at different times) encode in different ways, depending on the model mj that is being used. thus, as far as mental representations are concerned, there are two things to consider: a real-world object d with several aspects, and a human observer who uses a particular encoding procedure, the model mj, to encode the object and its aspects; in general, an object d can be interpreted with several alternative models. the distinction between an object and its aspects allows us to state three specific hypotheses about the conditions for perfect beauty. ( ) harmony. let dm be a mental representation of the data d given the model m. let d be composed of the aspects a ,…ai,…ak. according to the simplicity principle, the cognitive system will select a model m that minimizes k(dm), and if the aspects ai are perceived in isolation k(ai mi) will also be minimized. harmony requires that m = mi for all aspects of d. that is, the same model that is appropriate for d is also appropriate for its aspects ai. hence, the model m that is selected by the cognitive system among all possible models mi because it minimizes the kolmogorov complexity of d is also the model that is selected for each of its aspects. in other words, harmony implies that d as well as its aspects {a} can be encoded with the same procedure, the model m , and that the parts should fit the whole - that the cost of deriving a part from the whole is small: Σkk(aim dm ) is small ( ) another way to describe the harmony criterion is to make use of the relation between probability and complexity: max p(md) = min {k(m) + Σkk(ai m} that is, to minimize complexity, only a single model needs to be specified, not one for each aspect ai. edelman’s criterion of familiarity yields a method for finding minima; thus, for a set of faces di, mini k(di, mi) = average k(di, mj). ( ) variety. while harmony is a necessary condition, it is not a sufficient condition for beauty, because very boring objects could be generated in this way. a second requirement for a harmonious object to be perceived as beautiful is that its aspects are varied. while all aspects must fit the whole, the parts must be distinct from each other, which means that k(aim | ajm) > k(aim, ajm |dm). ( ) in words, the similarity between two aspects is smaller than the similarity between each aspect and the whole. thus, perfect form requires that the model that the cognitive system arrives at (the one that minimizes complexity) is the same for the whole and its aspects, and the aspects are distinct. that is, under the model m, it is more difficult to transform the aspects into each other than to transform each aspect into the whole. the obvious application of these ideas is to a painting or a sculpture, which is fully present as a physical object at any moment in time. yet it also applies to music and literature, which develop over time. a sentence or a musical phrase exists within the context of the whole work and must be interpreted taking into account what has come before as well as what still is to come. indeed, the difference between the visual arts and writing and music is more apparent than real, as the next criterion for perfect form will make obvious: a visual scene is present physically all at once, but its reception is anything but instantaneous. ( ) compression. the third requirement for perfect form requires viewing cognition as a dynamic system. mental representations are constructions, and constructions can change over time. as time passes, the model that an observer uses to encode a datum d changes. perfect form implies that the model changes in a particular way: it becomes ever better, in the sense that the complexity at time t+ is less than at time t, that is, harmony – how well parts fit the whole, given a particular model - increases: > Σkkt(aimdm) - Σk’kt+ (aimdm) ( ) a beautiful object allows for the compression of complexity; it affords the discovery of new harmonies. to make this constructive activity possible, both d and m must fulfill certain conditions. d must have a sufficient number of potential aspects, so that it is possible to discover new ones even after prolonged study. beautiful objects may have regularities, symmetries, fractal properties and the like that are not always discovered immediately. objects that do not have this potential, even though they may appear beautiful at first have no lasting appeal. d thus must have the potential for the discovery of novel aspects and harmonies. but equally important, the observer must have the capability and desire to develop new, simpler, compressed models, to take advantage of the affordances the object offers. that ability comes with experience and training; to really appreciate beauty one needs to become a connoisseur. connoisseurship is a kind of expertise. like all expertise it requires an intimate, long-term familiarity with a particular domain. to the connoisseur, things that only elicit a cursory look from most people become fascinating objects of contemplation and reanalysis. new aspects are discovered; familiar ones are seen in new ways. what the connoisseur does is best described as a continual process of complexity reduction: contemplation reveals new harmonies, new aspects. schmidhuber ( , ) has identified the compression of complexity with interest: objects are interesting when they afford compression with further study. interestingness, in this sense as complexity reduction , is seen as another factor in beauty. when we can always perceive something new in an object, when objects afford the discovery of new harmonies, we appreciate them most. when is complexity compression possible? if an object is so complex and unfamiliar that it is impossible for an observer to discover regularities in it, there will be no complexity reduction. a random display (or an object whose structure is so complex that it appears random) will remain random, and quickly becomes boring. at the other extreme, a totally familiar object that has been exhausted does not afford further possibilities for comprehension reduction – it too is boring. objects that are complex and unfamiliar enough afford complexity reduction. thus, eq. ( ) implies the well known u-shaped relation between interest and familiarity (wundt, ; berlyne, ): the very familiar and the totally unfamiliar are not interesting; what is just familiar enough tends to be interesting. the more one learns about something, the more one is able to appreciate its complexity. a good example is twelve-tone music (schmidhuber, ). to audiences a hundred years ago, as well as neophytes today, it appears as random noise. modern ears, however, have become used to it, are hearing something in it, can find it interesting and even beautiful – not as harmonious as mozart, but far from the aggressive cacophony that it once appeared to be. learning to see something as interesting and beautiful occurs not only with respect to art, but also nature. an experienced naturalist can make us see and appreciate things in nature, large and small, that we would have walked there are other sources of interest, too, besides compressibility: some things are intrinsically interesting – roughly, sex and violence. schmidhuber distinguishes between beauty and interest; here, interest is considered a criterion for beauty. this seems primarily a question of terminological preference. right past on our own. it was always there – the d is the same, but we learn to use a new model m that encodes d in a way that makes it interesting and, if the conditions of harmony and variety are also met, beautiful. complexity theory relates probability and complexity. predictions based on a model that yields minimum complexity and predictions based on maximum probability are the same. prediction plays an important role in the experience of beauty, not only with events that unfold in time, as in literature, music, dance, or ceremonies, but, as we have just argued, also with static objects such as a painting, a flower, or a landscape. beauty in music implies a model that maximizes the probability of the next element as we listen, but also that can be compressed, so that when we listen the next time, a new, more sophisticated model will guide our perception. why is it that we can read a great book many times and it becomes more interesting with each reading? because it affords us the opportunity to fine-tune our model, to construct a novel interpretation every time. the book remains the same, but we – our model – change. perfect form, thus, is a construction of the mind, involving the active participation of an informed observer. piaget described the cognitive development of children as an interplay between the processes as assimilation and accommodation (piaget, ; schmidhuber, ). assimilation means that old schemas are used to encode new information; in accommodation, new encoding schemas are generated. mental representations that we characterize as perfect form also involve assimilation in terms of an existing model, and accommodation through the evolution of a new model; however, not all forms of assimilation and accommodation result in the perception of beauty. the perception of beauty requires certain conditions to be satisfied - harmony and variety for assimilation, and compression for accommodation. with respect to the emphasis on the active contribution of the observer, the perception of beauty resembles other cognitive processes that have been traditional objects of study within cognitive science. there are, for example, numerous studies of the generation effect (e.g. mcnamara & healy, ) that show better memory for information that has been generated rather than information passively absorbed. similarly, the importance of actively constructing situation models in text comprehension and memory is widely attested (e.g., kintsch, ). the central role of background knowledge (e.g., kintsch, ) in the construction of situation models also has its parallel in the perception of beauty: the connoisseur with a lifetime of experience perceives things that escape the untrained eye or ear. thus, the study of aesthetic experience appears to be more closely related to the mainstream of cognitive science than is apparent at first. a simplified example of complexity computations in general, we are unable to specify either the mental representation of an object d or of the model m, which makes actual computations of complexity impossible. however, it is possible to illustrate the computations involved within specific models. for instance, current models of discourse comprehension make specific assumptions about the mental representation of a text and the model used to encode it. specifically, within the framework of the topic model (griffiths, steyvers, & tenenbaum, ) a text (or document) is represented as a multinomial probability distribution over topics. topics are semantic elements that are inferred from a linguistic corpus and are represented as probability distributions over the words of the corpus. thus, a model m may be defined as a set of n topics {ti} that are used to construct the mental representation of a document d, d = Σnpiti , where pi is the probability of topic ti. consider a story a that has aspects (e.g., paragraphs) a , a ,…, an and a set of topics {ti}. the aspects are the property of the data; the way they are encoded in terms of the available topics constitutes the model; the whole story as well as each aspect is to be represented with the same model, the n topics t. harmony requires that it is indeed possible to encode the whole as well as the parts with the same model, that is, the cost of transforming the aspects a , a ,…, an into the whole must be small (eq. ). variety requires that the parts are all different, that is, that the cost of transforming one aspect into another is large (eq. ). dynamics (eq. ) requires that there be another set of topics {t*} that yields less complex encodings than {t}. since we are comparing probability distributions, cost measures are simply the kl-divergence between them (eq. ). a serious test of such a model would be a major undertaking, requiring a careful selection of representative texts. at this point, all i can offer is a greatly oversimplified and highly artificial example – intended merely to illustrate the computations involved. consider two texts a and b, each with three sections, or aspects. our goal is to estimate how beautiful a and b are, taking into account only their content, not their stylistic and rhetorical properties. suppose that both texts as well as all their sections can be encoded with a model that has only two topics, t and t , with probabilities shown in table a and b. that is, both texts a and b load approximately equally on t and t , but a loads heavily on t while a loads mostly on t , and so on. to compare probability distributions we use the kullback-leibler divergence, eq. . harmony requires that the sections of each text as well as the text as a whole can be encoded with the two-topic model and that the divergence between the codes for the sections and the code for the text as a whole is small. the codes in this case are the probability distributions shown in table . using eq. , div (a , a , a a) = . and div (b , b , b b) = . . both of these numbers are small, so the parts fit the whole harmoniously in both cases. however, the three sections of a are more varied than the three sections of b. therefore, a but not b fulfills the variety criterion. specifically, ave div (aiaj) = . , while ave div (bibj) = . . that is, the sections of a are dissimilar, while those of b are not. text c, shown in table c, is an example of disharmony: a different model is required to encode each of its sections: c requires mostly topics t and t , c requires mostly t and t , and c requires mostly t and t . for this text, div (c , c , c c) = . , a higher value than was obtained for a and b. hence c fails the harmony criterion. finally, we illustrate the dynamic aspects of complexity reduction with the example shown in table d. what we have assumed here is that upon reflection, a new dimension is discovered for encoding text a. this discovery somewhat changes the old topic assignments, as we illustrate with the example in table d. the important point is that the additional dimension actually reduces the complexity of the code for a, div (a *, a *, a *a*) = . . thus, the parts fit the whole even better than before as required by eq. . hence of the three “texts” in table , only a fulfills all the criteria for perfect form. c scores too low on harmony; b lacks variety; but a is harmonious, varied, and as its code changes from a to a*, the kl-divergence has no upper bound. dynamic. needless to say that these examples are intended merely to show how the complexity computations proposed here might be realized. insert table here to see how far the above calculations are from a processing model of aesthetic perception, it is useful to consider solso’s distinction between levels of representation in art (solso, ): the surface information (e.g., visual properties of an artwork), the conceptual level (the concepts and ideas represented), and the interpretational level (including emotional responses), in analogy with the surface level- textbase-situation model representations in discourse comprehension (kintsch, ). the calculations presented here concern purportedly necessary conditions at solso’s second level. one could also regard them as formalizations of berlyne’s notions about the role of symmetry and balance in aesthetic perception (berlyne, ). they do not constitute a processing model, however. millis and larson ( ) have made a promising start in this respect, and the approach taken here might be compatible with their work. level- effects have also been studied, for example rhyme and alliteration in poetry (kintsch, ; lea et al., ). level- effects are easier to talk about than to model, but they too are open to experimental investigation, as shown, for example, by millis ( ), who manipulated inferences about paintings by the kind of titles he provided. the focus of the work discussed here has been on the nature of the mental representations that are experienced as beautiful and their dependence on both the features of a stimulus and the perceiver’s model that encodes that stimulus. alternatively, research on the perceptual fluency hypothesis (reber, schwarz, & winkielman, ) emphasizes the subjective experience of encoding fluency and the resulting positive affect as the source of beauty. it, too, sees beauty as a result of how people and objects relate. the two approaches make similar predictions about the characteristics of objects (e.g., symmetry, good gestalt) and perceivers (e.g., expertise), probably because perceptual fluency depends on low complexity and harmony, as defined here by eq. ( ). the variety condition (eq. ) that is proposed here as a criterion for perfect form is not accounted for by the perceptual fluency hypothesis, and neither is compression (eq. ), in part, because the experiments about perceptual fluency mostly employ rather simple stimuli and are concerned primarily with first impressions rather than the extended consideration of an object. perfect form and beauty to summarize, i have argued that the essential characteristic of perfect form is harmony. harmony is a property of mental representations. the mind constructs mental representations that have minimal complexity, that is, for a given datum d an encoding procedure or model m is selected that minimizes {k(m) + k(d|m)}. harmony is a relation between a mental representation {dm} and the mental representation of its aspects {a m,…,akm}: the whole d and its parts, the aspects, a ,…,ak, can all be encoded with the same model m in such a way that the aspects fit the whole, that is, the aspects can be derived from the whole: the cost of generating an aspect from the whole is low. harmony, however, is a necessary but not a sufficient condition for perfect form. an object must have aspects that are varied and distinct, and it must be interesting. distinctiveness can be defined in terms of conditional complexity: the complexity of going from the whole to the aspect, k(a|d) is low, while the complexity of transforming one aspect into another k(ai|aj) is high. interestingness here means the possibility of complexity reduction: contemplation of an object leads to the selection of a new model m* that yields a lower complexity encoding. in other words, an interesting object allows for active re-coding that improves predictability on the basis of newly detected harmonies and structures. the framework explored here emphasizes the crucial role of the perceiver, his or her model m, in the experience of beauty. indeed, it makes perceiving beauty a creative act. when it comes to the enjoyment of beauty in nature, it may be surmised that our native endowment allows every one to appreciate it, modulo some cultural biases, though here too exposure and experience play a significant role. when it comes to the perception of beauty in art, connoisseurship matters even more. to perceive beauty in art requires a well developed, sophisticated model that enables the mental construction of the artwork in the perceiver’s mind, to recreate it mentally in its ideal form. it certainly matters what the orchestra plays, or how the pianist plays, but what matters even more is what we hear, the heavenly music constructed in the mind of the listener or player. i started this essay with an argument to focus on perfect form instead of beauty. while understanding beauty is our goal, the concept of beauty is so overextended as to make an analysis extremely difficult. perfect form, instead, turned out to be much more tractable: we could analyze perfect form in terms of some kind of model selection. note that this move has allowed us to reconsider some of the factors that that made the concept of beauty so messy. a person’s model depends on his or her experience, knowledge, social conventions, taste. all the factors that we had initially excluded in favor of pure perfect form now find a new place within a novel framework: the question now becomes how mental representations are constructed, a promising research question for cognitive science, though as yet a poorly understood one. beauty, thus, comes in by the back door. how is perfect form to be achieved? how can we have both harmony and variety, and change as well? surely, there is no single, general answer to these questions, but rule systems must play an important role. constructing an object according to a system of rules is one way to achieve harmony: all of its aspects obey the same rules. of course, the rule system has to be complex enough to allow for diversity and dynamic reinterpretations. an example might be the rules that govern the composition of a fugue: start with a theme of several bars; replicate it with varied onset times; then stretch it, compress it, reverse it, mirror it, start changing it in subtle but surprising ways – in the hands of a skilled composer such a rule system can generate beauty. or take a more complex rule system, a twelve-tone series, and play the same sort of games with it to create endlessly varied structures. the danger here is that the rules generate such complex structures that they can no longer be perceived as harmonious. in the extreme, only the composer knows, our ears do not. another example from music is tonal ambiguity. a given note may have a place in more than one structure, it may, for instance, belong to one key, but can also be heard as part of a new modulation. similarly for visual ambiguity: the makers of village and nomadic rugs often play with figure-ground reversals, inviting the viewer to “a wanton kind of chase,” as hogarth put it. harmony is achieved here by adhering to strict rules in the construction of these textiles: the weave, the patterns, the colors, the use that a textile is intended for, are all conventionally determined. but these conventions leave the weavers enough freedom to generate a pleasing variety of objects. indeed, the physical constraints imposed by the very materials of construction may contribute to harmony: given the weft-and warp foundation and a decorative weft, there is only so much that is possible, which enforces coherence in the eventual product. lack of physical constraints in an artwork can be problematic: in a wood or marble sculpture, the material limits what can be done and imparts a degree of unity; in a plastic sculpture or video installation everything is possible – harmony and hence beauty becomes harder to achieve. this is not to say that beauty is not possible in the absence of physical constraints, nor that such constraints guarantee success. it simply means that technical limitations are not necessarily the enemy of beauty, and complete freedom not necessarily fruitful. truth and beauty the true and the beautiful are akin. truth is beheld by the intellect which is appeased by the most satisfying relations of the intelligible: beauty is beheld by the imagination which is appeased by the most satisfying relations of the sensible. james joyce, a portrait of the artist as a young man the concept of beauty, viewed in this way, is closely linked to that of truth. beauty is a property of certain kinds of mental representations, and the same properties may play a role in truth. in particular, the fitness criterion may be as relevant for truth as it is for beauty. one condition for truth may be that a model m is true if it makes possible an efficient encoding of a datum d and all its aspects. beauty may thus light the way to truth, as has indeed happened repeatedly in the history of physics. freeman dyson “points to several famous examples from the history of physics when theories designed to be beautiful turned out to be true. the best-known examples are the dirac wave-equation for the electron and the einstein theory of general relativity for gravity.” thus, there may be deep relations between the concepts of beauty and truth that remain to be explored. conclusions so what has been achieved with these musings about beauty? 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( ) grundzüge der physiologischen psychologie. leipzig: engelmann. table . examples of hypothetical documents a, b, and c, and their representations as probability distributions over topics. a. topic probabilities for text a and its three sections analyzed with a two-topic model. a a a a t . . . . t . . . . div(a ,a ,a a) = . b. topic probabilities for text b and its three sections analyzed with a two-topic model. b b b b t . . . . t . . . . div(b ,b ,b b) = . c topic probabilities for text c and its three sections analyzed with a six-topic model. c c c c t . . . . t . . . . t . . . . t . . . . t . . . . t . . . . div(c ,c ,c c) = . d topic probabilities for text a* and its three sections analyzed with a three-topic model. a * a * a * a* t . . . . t . . . . t . . . . div(a* ,a* ,a* a*) = . blinded by beauty: attractiveness bias and accurate perceptions of academic performance research article blinded by beauty: attractiveness bias and accurate perceptions of academic performance sean n. talamas*, kenneth i. mavor, david i. perrett school of psychology and neuroscience, university of st andrews, st andrews, united kingdom * st @st-andrews.ac.uk abstract despite the old adage not to ‘judge a book by its cover’, facial cues often guide first impres- sions and these first impressions guide our decisions. literature suggests there are valid facial cues that assist us in assessing someone’s health or intelligence, but such cues are overshadowed by an ‘attractiveness halo’ whereby desirable attributions are preferentially ascribed to attractive people. the impact of the attractiveness halo effect on perceptions of academic performance in the classroom is concerning as this has shown to influence stu- dents’ future performance. we investigated the limiting effects of the attractiveness halo on perceptions of actual academic performance in faces of university students. given the ambiguity and various perspectives on the definition of intelligence and the growing consen- sus on the importance of conscientiousness over intelligence in predicting actual academic performance, we also investigated whether perceived conscientiousness was a more accurate predictor of academic performance than perceived intelligence. perceived consci- entiousness was found to be a better predictor of actual academic performance when com- pared to perceived intelligence and perceived academic performance, and accuracy was improved when controlling for the influence of attractiveness on judgments. these findings emphasize the misleading effect of attractiveness on the accuracy of first impressions of competence, which can have serious consequences in areas such as education and hiring. the findings also have implications for future research investigating impression accuracy based on facial stimuli. introduction a review by langlois et al. [ ] suggested that people regularly make judgements based on appearance and argued that “if humans were not biased to judge others on their appearance, they would not need to remind their children not to judge books by their covers” (p. ). while frequently warned against ‘judging a book by its cover’, the field of face perception is filled with evidence that suggests that the face does contain a substantial amount of informa- tion for evaluators to infer traits. for instance, kramer and ward [ ] found that four of the big five personality traits, as well as physical health, were perceived with some limited accuracy plos one | doi: . /journal.pone. february , / open access citation: talamas sn, mavor ki, perrett di ( ) blinded by beauty: attractiveness bias and accurate perceptions of academic performance. plos one ( ): e . doi: . /journal.pone. editor: kun guo, university of lincoln, united kingdom received: september , accepted: january , published: february , copyright: © talamas et al. this is an open access article distributed under the terms of the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. data availability statement: all relevant data are available at http://dx.doi.org/ . /d ca af- ff- b - c - d aa c . funding: these authors have no support or funding to report. competing interests: the authors have declared that no competing interests exist. http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf http://creativecommons.org/licenses/by/ . / http://dx.doi.org/ . /d ca af- ff- b - c - d aa c http://dx.doi.org/ . /d ca af- ff- b - c - d aa c from internal facial features alone and three of the big five traits were accurately perceived (just above chance) from just one side of the face. similarly, penton-voak, pound, little, and perrett [ ] found that there was some limited accuracy in perceptions of extraversion, emo- tional stability, and openness to experience when presented with images of composite faces (combining the faces of people with the same personality). also, research by little, burt, pen- ton-voak and perrett [ ] found that evaluators were differentially attracted to faces depending on personality traits desired in a partner; that is, “if a trait is desired then faces perceived to pos- sess that trait are found more attractive than faces which do not possess that trait” (p. ). such research highlights potential accuracy in face perception and the relationship between limited accuracy in perceived traits and attractiveness. indeed, when investigating the accuracy of perceived intelligence [ ] and of perceived health [ ] in faces it was found that accuracy was improved to a level above chance when controlling for attractiveness bias. the ‘attractiveness halo effect’ in which desired personality traits are ascribed to attractive people over unattractive people [ ] seems to influence the use of attrac- tiveness as a cue when attempting to accurately perceive health or intelligence in faces and is in turn, limiting people’s accuracy. the relationship seems to reflect a suppression effect, in which the suppressor (perceived attractiveness) is correlated with the other predictor variable (per- ceived health or intelligence), but is not related to the dependent variable (actual health or intelligence), so when this noise (relationship between attractiveness and perceived health or intelligence) is controlled for the accuracy in perceptions of actual health or intelligence is increased [ – ]. accurate perceptions of intelligence and attractiveness halo kleisner, chvatalova, and flegr [ ] reported accurate perceptions of intelligence in men’s but not women’s faces. it is important to note that a significant relationship between perceived and actual intelligence was only evident after statistically controlling for perceived attractiveness, though perceived attractiveness itself was not found to be a valid cue to actual intelligence. kleisner et al. [ ] argue that one of the reasons accurate estimations of intelligence are demon- strated in men but not women may be due to the stronger effect of the attractiveness halo in perceptions of female intelligence. these findings highlight the pervasive and detrimental influ- ence of attractiveness on accuracy in attributions. for decades researchers have debated the accuracy in perceived intelligence and whether attractiveness is a valid cue to actual intelligence [ , , – ]. a study by zebrowitz, hall, mur- phy, and rhodes [ ] found that judgments of intelligence from faces were more accurate than chance for images from childhood, puberty, and middle adulthood, but not more accurate than chance in adolescence or late adulthood. zebrowitz et al. [ ] discussed how facial attractive- ness might relate to actual intelligence based on various potential paths: (a) biological, with good genes being inherited; (b) environmental, including the impact of nutrition and health- care; (c) influence of intelligence on grooming and health decisions; (d) and a self-fulfilling prophecy, in which attractive people are expected to be smarter and given greater opportunities to become smarter. a later study by zebrowitz and rhodes [ ] investigated the relationship between facial attractiveness and actual intelligence in the upper and lower halves of the attrac- tiveness distribution and reported that, consistent with the ‘bad genes hypothesis’, facial attrac- tiveness was a valid cue to actual intelligence only in the lower half of the attractiveness distribution. consistent with the ‘anomalous face overgeneralization hypothesis’, attractiveness was used (spuriously) as a cue to intelligence across the entire attractiveness distribution [ ]. thus, participants were accurate in judging intelligence based on attractiveness, but only because faces perceived as unattractive were judged as having low intelligence. these findings attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / are consistent with the ‘bad genes’ hypothesis, which implies that faces perceived as very unusual or unattractive may be an indicator of poor genetic fitness. a more recent study by mitchem et al. [ ] highlights several problems in previous research investigating attractiveness and intelligence, namely publication bias, inconsistencies in defini- tions of intelligence and attractiveness, research design flaws, and small sample sizes. they con- ducted research on the largest sample to date, utilizing a twin dataset and independently collected measures of facial attractiveness and general intelligence. they found no support for a relationship between actual intelligence and perceived facial attractiveness. attractiveness and academic performance research has also investigated the potential relationship between perceived attractiveness and actual academic performance, with no clear consensus. some investigations have showed that students who are perceived as more attractive achieve higher grades and higher scores on stan- dardized achievements tests (e.g. [ – ]). other studies failed to find any relationship (e.g. [ , ]). nonetheless, the relationship between perceived attractiveness and perceptions of academic performance is clear. a meta-analysis conducted by dusek and joseph [ ] scrutinized four- teen studies investigating physical attractiveness and its relation to teacher expectancy. the review concluded that perceived facial attractiveness is significantly correlated with teacher expectations of academic performance and positive personality attributes. for example, a cor- nerstone study by clifford and walster [ ] indicated a significant correlation between physi- cal appearance and teacher expectations. a similar study also suggested a positive correlation between teachers’ ratings of attractiveness and expectations of children’s skills [ ] showing that teachers judged children rated as more attractive as more social, confident, popular, aca- demically strong, and more likely to become leaders than students who were rated as less attractive. another meta-analytic review by ritts, patterson, and tubbs [ ] found that students per- ceived as attractive are more likely than students perceived as unattractive to be ascribed posi- tive educational traits. specifically, students perceived as attractive were judged as more intelligent, having more academic potential, and having better grades. it was also noted that other variables such as gender, race, and knowledge of past performance also influenced expec- tations, but were not significant moderators to the attractiveness influence [ ]. consequently, while there is little consensus and weak supporting evidence for a relationship between per- ceived attractiveness and actual intelligence or academic performance, there is convincing research documenting the relationship between perceived attractiveness and perceived intelli- gence or academic performance. accuracy in face perception research suggests extroversion can be accurately perceived after only a -ms exposure to a face [ ], strength can be accurately estimated from faces independent of height, weight, and age [ ] and the dark triad of personality (machiavellianism, narcissism, and psychopathy) can be accurately perceived in composites of expression-neutral facial images [ ]. note here that accuracy does not imply a large effect size; accuracy may be significant, but with performance only slightly above chance. nonetheless, this limited accuracy is still somewhat impressive given the lack of conventional information (i.e. information about behaviour) that we typically think affects such judgements; thus, the effects may be small but they are still noteworthy. todorov, olivola, dotsch, and mende-siedlecki [ ] suggests that little time is needed to arrive at a consensus on social attributions from faces, however many studies overstate the validity of attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / these attributions. there are various perspectives on why and how such social attributions from faces are made that explain the potential both for accuracy and for limitations in accuracy. biological cues may shed light on how people are rating social judgements at above-chance accuracy from neutral-expression facial images alone. for instance, research suggests the shape of a face is related to the current [ – ] and prenatal [ ] levels of testosterone. research has also suggested that facial adiposity is closely associated with circulating testosterone [ ] and that facial adiposity has been shown to be related to perceived health and attractiveness, as well as measures of actual cardiovascular health and proneness to respiratory illness [ ]. further, facial symmetry, and sex typicality in face shape has been shown to be related to disease resis- tance [ ]. similarly, an average face shape may signal health, as abnormalities that make a face look slightly different from the average may be caused by genetic or environmental stress [ ]. carotenoid coloration in the face has also been found to signify quality of current diet [ ]. the face can also provide clues to recent sleep history, with those who are sleep deprived hav- ing less eyelid-openness and more downward mouth curvature than those that are well rested [ ]. health, attractiveness and over-generalization clearly, the face provides a variety of cues to hormones, health, and sleep status. one thing all of these cues have in common is their relationship to attractiveness. namely, research investi- gating attractiveness and the ‘good genes’ theory has argued that facial symmetry [ ], average- ness [ ], sexual typicality [ ], eyelid-openness and mouth-curvature [ ], carotenoid coloration in the face [ ], and adiposity [ ] may be attractive because of their relationship to health [ – ]. the link between potential cues to health in the face and perceived attractiveness is one explanation for the ‘attractiveness halo effect’. research suggests this preference for attractive (or healthy looking) individuals appears early in infancy, with infants as young as two-months old gazing longer at attractive faces over unattractive or unusual looking faces [ , ]. it is unknown whether or not such preferential looking reflects early learning [ – ]. further, langlois, roggman, and reiser-danner [ ] found that twelve-month-old infants would play longer, have more involvement, experience less distress and withdrawal, and seem to exhibit more pleasure when interacting with attractive people as compared to unattractive people. also noteworthy is the degree of agreement regarding facial attractiveness. specifically, studies have shown consistency between men and women regarding opinions of facial attractiveness [ ]. surprisingly, agreement on facial attractiveness is apparent even across different countries [ , ]. in an attempt to investigate whether facial attractiveness provides evidence of actual health, which may partially explain this positive bias towards attractive people, kalick, zebrowitz, lan- glois and johnson [ ] found that evaluators’ perceptions of attractiveness are actually poor pre- dictors of current or future actual health. while attractive faces were mistakenly rated as healthier than their peers, the correlation between perceived health and actual health increased when attractiveness was statically controlled, implying that attractiveness suppresses the accu- rate recognition of health. this improvement in accuracy of health judgments after controlling for attractiveness is similar to the improved accuracy of intelligence judgments when the attractiveness halo is sta- tistically controlled [ ]. indeed there is evidence to suggest a relationship between various health factors and cognitive or intellectual performance. specifically, it has been found that phobic anxiety [ ], trait anxiety [ , ], drug use [ ], diabetes [ , ], poor sleep [ ], and attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / frailty [ ] have been negatively associated with both health and cognitive function in older individuals. similarly, exposure to chronic aircraft noise [ ], infection with parasitic worms [ ] and food insufficiency [ ] have been found to negatively impact health and cognitive per- formance in children. given the close relationship between actual health, actual cognitive per- formance, and perceived attractiveness, facial cues to health might also be cues to both attractiveness and cognitive ability, leading to correlations between attractiveness and per- ceived competence. such correlation might lead to overgeneralization and inaccurate percep- tions of academic ability in healthy individuals based spuriously on attractiveness. hence we explore whether or not the ‘blinded by beauty’ phenomenon found in perceptions of health [ ] and intelligence [ ] also applies to the perception of academic performance from first impres- sions of neutral-expression static facial images. theories of intelligence and academic performance given the controversy over definitions of intelligence and differences in theories of intelligence [ ] it is likely that, in addition to being limited by the attractiveness halo, accurate perceptions of intelligence are also limited by variation in understanding on the meaning of the term ‘intel- ligence’. while someone who agrees with a fixed theory of intelligence believes there is little a person can do to change their actual intelligence, someone with a growth theory of intelligence argues that intelligence can change over time with the appropriate environment [ – ]. perceptions of academic performance from faces are likely to suffer similar inconsistences in evaluator perspectives of what factors most influence academic performance. while research has consistently shown that intelligence predicts academic performance [ ], it is well docu- mented that the personality trait of conscientiousness is a stronger predictor of academic per- formance than intelligence [ , ]. hence, it could be argued that asking evaluators to assess academic performance from faces would yield just as much ambiguity as attributions of intelli- gence, as consensus would be adversely affected both by disagreement in fixed vs. growth theo- ries of intelligence, and by different perspectives on how much academic performance relies on intelligence versus conscientiousness. research on the intelligence competence theory (ict) further undermines consensus of perceived academic performance by suggesting that people who are less intelligent compensate by becoming more conscientious to reach their goals [ , ]. thus, some might think a person with a less intelligent looking face is more academically able because the person may work harder to get better grades. previous studies have highlighted consensus and accuracy of per- ceptions of most of the big five personality traits from face, yet conscientiousness is sometimes [ ], but not always correctly detected [ , ]. given the relationship between actual conscien- tiousness and academic performance (compared to intelligence), we explore whether percep- tions of conscientiousness are more likely to predict actual academic performance than perceptions of intelligence. research questions research investigating perceptions of academic performance has primarily been concerned with exploring the potential of attractiveness to be a valid predictor of academic performance [ – , ] and exploring the effects of perceived academic performance on students’ actual performance in the future [ – ]. no research that we are aware of has investigated the poten- tial accuracy of perceptions of actual academic performance from faces when controlling for the attractiveness halo. given the different perspectives and theories of the term ‘intelligence’ [ , , ] and the varying perspectives on how much intelligence predicts academic perfor- mance compared to conscientiousness [ , ], we hypothesize that evaluators will be more attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / accurate in perceiving actual academic performance when specifically asked to rate conscien- tiousness than when asked to rate the more ambiguous terms ‘intelligence’ or ‘academic performance’. further, it is possible that attractiveness detracts from accuracy in perceptions of academic performance much as attractiveness can detract from accuracy in perceptions of health and intelligence. while there are various seemingly logical explanations for why attractiveness could be a valid cue to academic performance, the empirical evidence for a link between the two is extremely weak and perhaps only existing in the lower half of the distribution (i.e. driven by potential outliers with genetic or developmental problems affecting both appearance and cognitive ability). we hypothesise an ‘attractiveness halo’ in which attractiveness is not linked to actual academic performance but is significantly correlated with perceptions of academic performance. further, we hypothesise that controlling for the misperceptions about attractive- ness may improve accuracy in perceptions of academic performance. we argue that this effect of controlling for attractiveness takes the form of a classic type of suppression (see [ – ]). in classical suppression, the suppressor is unrelated to the variable of interest but is related to the predictor, and therefore the shared variance between the predictor (in this case, perceived conscientiousness, intelligence or academic performance) and the sup- pressor (attractiveness) is unrelated to the outcome measure (actual academic performance). by controlling for this irrelevant variance in the predictor, the strength of the association between the predictor and outcome variable increases. in other words, controlling for attrac- tiveness may reveal a ‘blinded by beauty’ phenomenon similar to that found in health [ ] and intelligence [ ] judgments. method all data collection was approved by utrec and the school of psychology and neuroscience ethics committee (ps ), university of st andrews. all participants provided informed writ- ten consent and were debriefed accordingly. the individuals in this manuscript have also given written informed consent to blend their facial photographs to create average faces and publish these case details. written consent was recorded via both electronic submission and on hard copies. the ethics committee approved this consent procedure. facial stimuli students from the university of st andrews were recruited to take part in an experiment called “influences in the perception of intelligence in faces” as part of a larger data collection. one- hundred of the most standardized (e.g. clean shaven, neutral expression and head posture) caucasian faces between the ages of and (mage = . , sd = . ; females, males) were chosen as stimuli. the original image collection contained more women than men and removal of males with beards enhanced the gender bias. nonetheless, we maximised the num- ber of stimuli available for judgments to maintain power in the analysis. selection of standard- ized faces was done blind to their academic performance. todorov and porter [ ] highlight significant differences in person impressions within multiple facial photos of the same person due to random variation and discuss how this can influence accuracy of personality inferences based on faces. thus, it was important to select the most standardized stimuli. all of the stimuli photographs of participants used were taken under standardized lighting conditions and cam- era set-up; individuals had their hair pulled back, did not wear any kind of make-up or jewel- lery, and were instructed to pose with a neutral facial expression. face images were aligned on left and right pupils. images were then resized and cropped ( x pixels) so that an equal proportion of hair and neck was exposed in each. attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / academic performance measures all participants consented to releasing their academic performance records for the purpose of this research. academic records were accessed via the universities database. academic perfor- mance at the university of st andrews is marked on a -point scale reported to one decimal place for final module grades. an average academic performance was calculated by taking the grade point average (gpa) across every year weighted by every module credit completed by the student. participants varied in their course of study and the number of modules completed based on their year and semester of study ( in sciences, in arts; first and second year undergraduates, third and fourth year undergraduates, and in postgraduate courses). accordingly, methods of evaluation (e.g. exam, essay, and dissertation) varied. face ratings four separate groups of participants were recruited and paid via amazon mechanical turk to obtain ratings of perceived attractiveness, intelligence, conscientiousness, and academic perfor- mance (no other face ratings obtained for this study). table shows the demographics of each participant group. differences in sample sizes were based on differences in the number of par- ticipants completing the task while the link was live on amazon mechanical turk and number of exclusions. participants who reported their ethnicity as different from ‘white caucasian’ were excluded when calculating the average ratings of perceived attractiveness, intelligence, conscientiousness, and academic performance, as stimuli presented were caucasian and judg- ments of other ethnicities may be more susceptible to stereotypes [ ]. analysis was re-run with all participants and there were no differences in the pattern of findings; i.e., all significant results remain significant, and all non-significant results remain non-significant. evaluators first previewed all stimuli with each image displayed for one second. the stimuli were then re-presented so that participants could rate the face on the focal trait for each sam- ple: perceived attractiveness, intelligence, consciousness, or academic performance. faces were presented in random order. to ensure the paid participants were not quickly and hastily click- ing through images, images were presented for at least one second before participants were allowed to continue to the next image, but no maximum response time was enforced. evalua- tors then completed a questionnaire inquiring about their age, gender, and ethnicity. facial ratings were done on a -point scale with endpoints according to the face rating task: attractiveness endpoints were not at all attractive to very attractive; perceived intelligence end- points were not at all intelligent to very intelligent; perceived conscientiousness endpoints were not at all conscientious to very conscientious.; and perceived academic performance endpoints were very low academic performance to very high academic performance. participants who rated perceived academic performance were presented with a statement at the top of each facial image presented asking “please rate how well you think this person does table . sample information. participant group m age sd age exclusions total sample gender attractiveness . . f = m = intelligence . . f = m = conscientiousness . . f = m = academic performance . . f = m = each participant group reflects a separate group of raters for one face perception task. female is represented by f and male by m. doi: . /journal.pone. .t attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / in university compared to the other people presented”. participants who rated perceived con- scientiousness were presented with a statement at the top of each facial image presented that read “conscientiousness is the personality trait of being thorough, careful, or vigilant–with the desire to do a task well. based on the definition of conscientiousness provided–how conscien- tious do you perceive this face to be compared to the other faces presented”. results an average score of perceived attractiveness, intelligence, academic performance and conscien- tiousness was calculated for each of the faces based on the average of all the evaluator rat- ings. table gives the zero order correlations between ratings and academic performance and demographic variables. there was a significant correlation between older age and higher actual academic performance and female faces were perceived as more attractive (see table ). as predicted, there was no relationship between attractiveness and actual academic perfor- mance (r = . ), but a strong positive correlation between attractiveness and perceived intelli- gence (r = . ), attractiveness and perceived academic performance (r = . ) and attractiveness and perceived conscientiousness (r = . ). given the high correlations between rated attributes (perceived attractiveness, perceived con- scientiousness, perceived intelligence and perceived academic performance), we wanted to ensure that any statistical controls were based on sufficiently reliable measures and discriminability valid constructs. cronbach’s alphas were calculated for perceived attractiveness ( ratings; α = . ), intelligence ( ratings; α = . ), academic performance ( ratings; α = . ), and conscien- tiousness ( ratings; α = . ). after correcting for attenuation due to measurement error [ , ] the relationships between attractiveness and perceived intelligence (r = . ), between attractiveness and perceived academic performance (r = . ), and between attractiveness and perceived conscientiousness (r = . ) were all marginally higher but do not indicate redundancy. we explored any potential issues with multi-collinearity, as research has suggested high vif calculations may raise concerns over interpretations [ ]. the test to see if the data met the assumption of collinearity indicated that multi-collinearity was not a concern (vif scores over are seen as problematic; [ ]). in this study none of the vif values were a concern: perceived attractiveness, tolerance = . , vif = . ; perceived academic performance, tolerance = . , vif = . ; perceived intelligence, tolerance = . , vif = . ; perceived consciousness, toler- ance = . vif = . ). table . zero-order matrix. actual academic performance . age . ** . sex -. -. . attractiveness . . ** -. ** . intelligence . . ** -. * . *** . conscientiousness . † . ** -. *** . *** . *** . academic performance . . ** -. . *** . *** . *** zero-order correlations in which rated academic performance is correlated with facial attractiveness, perceived intelligence and perceived conscientiousness. sex is coded female = , male = . correlations are based on faces. ***p < . . **p < . . *p < . †p < . . two-tailed probabilities. doi: . /journal.pone. .t attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / partial correlations were conducted in which the influence of age of face, sex of face, and perceived attractiveness were controlled for. partial correlations revealed (see fig ) a signifi- cant correlation between perceived conscientiousness and actual academic performance (r = . , p = . ). the partial correlations reveal no relationship between actual academic performance and perceived academic performance (r = . , p = . ) or perceived intelli- gence (r = . , p = . ). findings do not change when controlling for only attractiveness in the partial correlation. nor do they change when controlling for the combination of attractive- ness and age or the combination of attractiveness and sex of face. we investigated the predictive power of perceived conscientiousness over attractiveness and the other perceived competence variables with a multiple linear regression model. in a simple regression model perceived conscientiousness significantly predicted actual academic performance (b = . , se = . , % ci [ . , . ], p = . , β = . ), but perceived academic perfor- mance (b = - . , se = . , % ci [- . , . ], p = . , β = - . ), perceived attractiveness (b = - . , se = . , % ci [- . , . ], p = . , β = - . ), and perceived intelligence (b = - . , se = . , % ci [- . , . ], p = . , β = - . ) did not significantly predict actual aca- demic performance (overall model: adjusted r = . , f( , ) = . , p = . ). in a multi-step hierarchical model ( st step independent variables: perceived attractiveness, perceived intelligence, perceived academic performance, nd step independent variable: per- ceived conscientiousness) predicting actual academic performance, the second step in the model (perceived conscientiousness) showed a significant increase in variance explained (r change = . p = . ). facial averages facial averages of faces were created to help the reader visualize perceptions of conscientious- ness and the attractiveness halo. all face images were manually delineated with points. the averaging (a) computes the average coordinate values for facial landmarks within the set of face images, (b) warps each shape of each facial image into these average coordinates, and then blends the warped component images [ , ]. facial averages (see fig ) were synthesized fig . partial correlations. this bar graph shows the increased accuracy of the different perceived competence variables when controlling for perceived attractiveness. the same pattern emerges when controlling for the additional variables of sex and age of face. doi: . /journal.pone. .g attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / from the top % male and female faces ( male and female faces) and bottom % male and female faces with the highest and lowest scores on perceived conscientiousness [ , ]. these average images were then made symmetrical (see [ ]). discussion there are three main findings. first, there was no first-order relationship between perceptions of conscientiousness, academic performance or intelligence and actual academic performance. second, when controlling for the expected influences that age, sex and perceived attractiveness on perceptions of competence (perceived conscientiousness, academic performance and fig . composite images of percieved consientiousness. the images presented reflect the top and bottom % of faces percieved as most (left) and least (right) conscientious. the attractiveness halo would suggest that faces percieved as most conscientious (left) would be more attractive than the faces rated as least conscientious (right). doi: . /journal.pone. .g attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / intelligence), then the relation between perceived competence and actual academic perfor- mance increased in strength. third, perceived conscientiousness was the single best face per- ception predictor of actual academic performance (outperforming perceived intelligence and perceived academic performance), and again accuracy was significantly improved when con- trolling for the suppressor variable of attractiveness. as we expected, the form of the relationship is one of classic suppression in which there is some factor (perceived attractiveness) that is correlated with perceptions of conscientiousness, but not correlated with actual academic performance [ – ]. when this factor is controlled, the relationship between perceived conscientiousness and actual academic performance is increased (see fig ). it should also be noted that, although some previous literature suggests weak correlations between attractiveness and cognitive performance measures [ ], in our study perceived attractiveness was not a valid cue to actual academic performance. these results suggest that we are ‘blinded by beauty’ in a way in which we would be more accurate in our perceptions of academic performance from faces if we were not influenced by the ‘attrac- tiveness halo’ effect. given the amount of research on higher expectations and desired educational traits being ascribed to attractive students over unattractive students, it is not surprising that faces that were rated as more intelligent, having better academic performance and being more conscien- tious were also rated as more attractive (see composite faces in fig ). as predicted, there were high correlations between perceptions of attractiveness and perceptions of intelligence, consci- entiousness, and academic performance, likely reflecting the strength of the attractiveness halo, as well as the similarities among these perceived competence measures [ ]. while there is less evidence to suggest perceptions of intelligence and academic performance are unique con- structs, the possibility that perceived conscientiousness and perceived attractiveness are not distinguishable empirically is dealt with in two ways: face validity of the items for which evalua- tors were clearly rating conscientiousness or attractiveness (the measures were unambiguous to the evaluators); and we calculated inter-evaluator reliabilities for conscientiousness and attrac- tiveness ratings and even after correcting for attenuation due to measurement error, the corre- lations between these variables remained distinct (i.e. they were imperfectly correlated). taken together, these elements suggest that these measures can be treated here as distinct constructs, and that they are measured with sufficient reliability to be distinguished empirically in this study. the high correlations do create potential for interpretative difficulties in multiple regres- sion, and under such circumstances we find it important to emphasize the role of suppression in their relationship in a way that reflects the traditional understanding of the attractiveness halo. findings suggest that accuracy in perceptions of academic performance also increases with the clarity and validity of the question proposed. when controlling for attractiveness, age and sex, perceptions of conscientiousness in faces yielded above chance accuracy in predicting aca- demic performance, but accuracy in predicting actual academic performance did not reach lev- els of statistical significance with perceptions of intelligence or perceptions of academic performance. given the high correlations between these perceived competence measures, it is difficult to say for certain whether perceptions of conscientiousness are unique in their capacity to predict actual academic performance over and above perceptions of intelligence or academic performance. rather, it seems perceptions of conscientiousness predicts actual academic per- formance because, in comparison, it may be the least ambiguous competence construct. as pre- viously argued, it is likely that individual differences in theories and understandings of intelligence can lead, on average, to less accurate perceptions of intelligence in faces. likewise, perceived academic performance is possibly confounded by a combination of the ambiguities in the term intelligence (fixed vs. malleable) and the limited consensus on how much attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / fig . attractiveness suppression. this figure shows the noise in perceived conscientiousness (the overlap between perceived attractiveness and perceived conscientiousness) and how by suppressing this noise results in an improved predictor of actual academic performance (greater overlap between the remaining perceived conscientiousness and actual academic performance). doi: . /journal.pone. .g attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / intelligence (in relation to conscientiousness) is necessary for high academic performance; hence the limited accuracy of perceived academic performance compared to perceived consci- entiousness in predicting actual academic performance. the improved accuracy in perceived conscientiousness predicting actual academic perfor- mance over perceived intelligence is also consistent with research that suggests that actual con- scientiousness is a stronger predictor of academic performance than actual intelligence [ ]. further, the intelligence compensation theory (ict) suggests that conscientiousness acts as a coping strategy for relatively less intelligent people. while evidence for ict is limited, some studies have found significant negative correlations between fluid intelligence and conscien- tiousness [ , ]. other studies have found a significant negative correlation between crystal- ized intelligence and conscientiousness [ ]. thus, our findings of perceived conscientiousness better predicting actual academic performance in faces than perceived intelligence is consistent with literature suggesting actual conscientiousness is a better predictor than intelligence in pre- dicting actual academic performance. nonetheless, given the high correlations amongst the perceived competence variables explored (perceived intelligence, perceived academic perfor- mance and perceived conscientiousness), we must be cautious in claiming that only perceived conscientiousness is related to actual academic performance; rather we argue that the specific- ity in rating tasks and the influence of attractiveness bias are worth considering when exploring validity of judgements based on faces. the increased accuracy of academic performance in faces after controlling for attractiveness has important implications. indeed, olivola and todorov [ ] showed that judges overweigh aspects of appearance and would be more accurate in judging personality if face perception was ignored. however, facial impressions have consistently been shown to influence our opin- ions as well as bias decisions in politics [ ], leadership [ ], law [ ], parental expectations and punishments on children [ ], military rank promotion [ ], and teacher evaluations [ ]. clearly, the power of first impressions is critical and has repeatedly been shown to influence our opinions about a person. furthermore, research has found that femininity is considered more attractive than mascu- linity [ ] and that females perform better academically and stay in education longer than males [ ], which likely leads to females being ascribed more desired educational traits over men. it is also well documented that older students do better on intelligence tests [ , ] and do better academically than younger students. moreover, crystalized intelligence and percep- tions of wisdom have shown to increase linearly with age [ , ], which would influence impressions of competence in older students (hence the intentionally limited university age range for facial stimuli presented). our research suggests that when controlling for biases of attractiveness, age and sex, independently or collectively, accuracy of perceived academic per- formance is significantly improved. perhaps one of the most alarming consequences of using insufficient information to guide first impressions is the expectancy effect in education. the classic pygmalion study conducted by rosenthal and jacobson [ ] suggests that expectations alone are capable of influencing the targets’ actual performance. specifically, the pygmalion study found that students who were arbitrarily assigned the label ‘bloomers’ (i.e., anticipated to show future promise) eventu- ally scored higher on future tests than other students, even though the students labelled as ‘bloomers’ were a random sample and not any more intelligent than the other students in the class. more recent research on expectancy effects by sorhagen [ ] found that teachers’ inac- curate expectations of students in first-grade was associated with students’ academic perfor- mance in high-school and that students from lower income families were especially influenced by this bias. likewise, de boer, bosker, and van der werf [ ] defined expectation bias as the difference between observed and predicted teacher expectation and found a significant attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / relationship between teacher’s expectation bias of students’ performance and actual perfor- mance years later. hence, perceptions of conscientiousness, intelligence and academic perfor- mance may play a vital role in the classroom environment and in the success of a child’s education. future research in face perception can benefit from noting the significant differences in per- ception accuracy based on different theories of intelligence or competence. perhaps more importantly, given the well documented effects of expectations of academic performance on actual academic performance, our findings help emphasize the biased effects of perceived attractiveness on expectations of academic performance. while it seems unlikely that another person’s attractiveness can be filtered out when attempting to accurately perceive academic performance, the mere knowledge of the negative influence attractiveness has on accuracy may encourage less biased practice; for perhaps the best antidote to deter unconscious bias is to make conscious the possibility of bias. acknowledgments we thank martin campbell for his very helpful feedback on earlier versions of the manuscript. we also thank william peter for his assistance in participant recruitment. author contributions conceived and designed the experiments: st dp. performed the experiments: st. analyzed the data: st dp km. contributed reagents/materials/analysis tools: st dp km. wrote the paper: st dp km. references . langlois jh, kalakanis l, rubenstein aj, larson a, hallam m, smoot m. maxims or myths of beauty? a meta-analytic and theoretical review. psychol bull. ; ( ): – . 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/a . accessed january . attractiveness bias and accurate perceptions of academic performance plos one | doi: . /journal.pone. february , / http://dx.doi.org/ . /j. - . . .x http://www.ncbi.nlm.nih.gov/pubmed/ http://www.ncbi.nlm.nih.gov/pubmed/ http://www.ncbi.nlm.nih.gov/pubmed/ http://doi.apa.org/getdoi.cfm?doi= . /a http://doi.apa.org/getdoi.cfm?doi= . /a ijwh- -estrogen-formulations-and-beauty-care-practices-in-japanese- © takeda et al, publisher and licensee dove medical press ltd. this is an open access article which permits unrestricted noncommercial use, provided the original work is properly cited. international journal of women’s health : – international journal of women’s health estrogen formulations and beauty care practices in japanese women takashi takeda tze fang wong mari kitamura nobuo yaegashi department of obstetrics and gynecology, tohoku university graduate school of medicine, miyagi, japan correspondence: takashi takeda department of obstetrics and gynecology, tohoku university graduate school of medicine, seiryomachi – , aoba-ku, sendai - , miyagi, japan tel + fax + email take@med.tohoku.ac.jp purpose: traditionally, oral estrogens have been used for hormone replacement therapy. however, in japan, additional estrogen formulations have been used, including transdermal patches and transdermal gels. the latter have a unique commonality with cosmetics because both of them are applied to the skin. beauty care is one of the most important lifestyle factors for women, and it has been reported that the amount of attention paid to beauty care has an effect in determining whether or not women will choose to undergo hrt during menopause. therefore, our study focused on estrogen formulations and beauty care practices. patients and methods: fifty women who use hormone replacement therapy were recruited from the outpatient clinic of tohoku university hospital. they were treated with oral conjugated estrogen (n = ), transdermal β-estradiol patch (n = ), and transdermal β-estradiol gel (n = ). they completed a questionnaire to assess their lifestyle (beauty care practices and exercise habits) and their compliance. the transdermal gel users were further interviewed about their subjective impressions regarding “smell”, “sticky feeling”, “spreadability”, and “irritation” on the skin using a five-grade scale. results: there were no differences in the usability of medicines and patient compliance among the estrogen formulations. we observed a positive tendency between the level of beauty care and transdermal gel use (p = . , ordinary logistic regression analysis). the gel users placed top priority on a lack of “sticky feeling” but the subjective impression regarding “sticky feeling” was worst among the four factors (p , . , steel–dwass test). correspondence analysis showed that the subjective impressions of transdermal gel corresponding to usability in the range of “moderate” to “very good” and “sticky feeling” greatly affected the usability of the formulation. conclusion: these results suggest that the level of attention to beauty care plays some role in the choice of estrogen formulations. keywords: hrt, estrogen, transdermal gel, cosmetics, subjective impression introduction hormone replacement therapy (hrt) has been widely used for the control of vasomotor symptoms of post- and perimenopausal women. , hrt is also employed for the treatment of premature ovarian failure (pof). women with untreated premature ovarian failure are at increased risk of osteoporosis, cardiovascular disease, and dementia, among others. the common types of estrogen for estrogen therapy are conjugated equine estrogen and -β-estradiol. there are no data to suggest that any one formulation is clinically superior to another. traditionally, oral estrogens have been used for estrogen therapy, but they have several disadvantages such as variable bioavailability and hepatic first-pass metabolism. to circumvent the side effects of dovepress submit your manuscript | www.dovepress.com dovepress o r i g i n a l r e s e a r c h open access to scientific and medical research open access full text article http://dx.doi.org/ . /ijwh.s in te rn a tio n a l j o u rn a l o f w o m e n 's h e a lth d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -m a y- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / mailto:take@med.tohoku.ac.jp www.dovepress.com www.dovepress.com www.dovepress.com http://dx.doi.org/ . /ijwh.s international journal of women’s health : the oral route, approaches using the transdermal route have been developed. transdermal formulations, such as trans- dermal patches and transdermal gels, are available in japan. transdermal gels have a unique commonality with cosmetics because both of them are applied on the skin. beauty care is one of the most important lifestyle factors for women. it has been previously reported that the amount of attention paid to beauty care plays a role in determining hrt during menopause. women tend to expect anti-aging effects such as maintaining a youthful appearance, improving skin tone, and preventing wrinkles to accompany hrt use. however, there have been no reports about the type of estrogen formulations and beauty care practices. in this study, we have investigated the relationship between estrogen formulations and beauty care practices and studied the usability of transdermal gel according to its cosmetic aspects. material and methods the study was carried out in accordance with the principles outlined in the declaration of helsinki. our institutional review board at tohoku university approved the study ( - ). study population a cross-sectional study was conducted from november to december . fifty women, aged – years, who use hrt were recruited from the gynecologic outpatient clinic of tohoku university hospital in sendai, japan. they were all diagnosed with loss of ovarian function. they provided informed consent and could complete a questionnaire by themselves. they had used the same type of estrogen formula for at least months. questionnaire the questionnaire consisted of four parts. the first part included general profile factors such as age, occupation, time from the initiation of treatment to screening, type of estrogen (oral tablet, transdermal patch, or transdermal gel), and medi- cal application. according participants’ answers to this part, we divided the subjects into three groups: group , oral-con- jugated estrogen (premarin®; pfizer, tokyo, japan) . mg/ day (n = ), group , transdermal β-estradiol patch (estrana®; hisamitsu, tokyo, japan) . mg/ days (n = ), and group , transdermal β-estradiol gel ( devigel®; motida, tokyo, japan) mg/day (n = ). the second part addressed usability and compliance. we asked, “what is the usability of your estrogen formula?” with the possible responses of “favorable”, “rather favorable”, “neutral”, “rather unfavorable”, or “unfavorable”. we also asked, “how often do you forget your medication per month?” with the pos- sible responses of “never”, “once”, “twice”, “three times”, or “more than three times”. the third part included questions about lifestyle (beauty care practices and exercise habits) with four grades. as to the beauty care practices, we asked, “how often do you put on makeup?” with the possible responses of “every day”, “sometimes”, “rarely”, or “never”. as to their exercise habits, we asked, “how often do you engage in mild exercise?” with the possible responses of “once a week”, “once a month”, “once per months”, or “never”. the transdermal gel users were further interviewed in the fourth part of the questionnaire. we asked about their prior- ity regarding “smell”, “sticky feeling”, “spreadability”, and “irritation” on the skin using a four-grade scale. subjective impressions regarding these factors were also gathered using a five-grade scale. analysis the significance of differences was evaluated by chi-square test, kruskal–wallis test, or steel–dwass test. statistical analysis was performed using excel ( ; microsoft cor- poration, redmond, wa) with the add-in software statcel (oms, tokyo, japan), and sas (v . . ; sas institute inc, nc, us). statistical significance was set at p , . . results general profile we began by analyzing the questionnaire results for part . demographic and clinical characteristics are shown in table . the tablet group was younger than the gel group (p , . ). there were no differences between the groups with regards to occupation, time from the initiation of treat- ment, and medical application (p . . ). usability and compliance the questionnaire results for part are shown in table . there were no differences between the groups with regard to usability and compliance (p . . ). beauty care practices and exercise habits next we analyzed the questionnaire results for part (table ). there were no differences between the groups with regard to beauty care practices and exercise habits (p . . ). we further divided the subjects into three groups according to the frequency of beauty care practices and exercise habits (figure ). there were no differences submit your manuscript | www.dovepress.com dovepress dovepress takeda et al in te rn a tio n a l j o u rn a l o f w o m e n 's h e a lth d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -m a y- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of women’s health : between the groups with regard to age. according to the ordinary logistic regression analysis, we could detect a posi- tive tendency, although it was not statistically significant, between the level of beauty care practices and transdermal gel use (p = . ). priority and usability for transdermal gel users we further analyzed the questionnaire results for part ( figure ). transdermal gel users gave the highest priorities for lack of “sticky feeling” and lack of “irritation”. as to the subjective impression of gel usability, “sticky feeling” had the lowest rating. correspondence analysis of the subjective impression and the usability of transdermal gel next we analyzed the relationship between the subjective impression of gel usability and the usability of gel. correspondence analysis graphically showed that the subjective impressions of transdermal gel corresponding to usability in the range of “moderate” to “very good” and “sticky feeling” greatly affected the usability of the formulations (figure ). discussion this is the f irst report about the relationship between estrogen formulations and beauty care practices; we also studied the usability of the transdermal gel according to its cosmetic aspects. tr a n s d e r m a l e s t r og e n a d m i n i s t r a t i o n by p a s s e s f irst-pass metabolism and offers some advantages over oral administration. in view of these advantages, we rec- ommend the administration of transdermal formulations (patch or gel) for all hrt users in our clinic. this would explain the high percentage of transdermal administration. however, there are some disadvantages, such as skin table demographic and clinical characteristics group (tablet) n = group (patch) n = group (gel) n = age (years) mean (se) . ( . )* . ( . ) . ( . ) occupation business worker individual proprietor part-time worker housewife unemployed others p = . (by chi-square test) time from initiation of treatment (months) , – – . p = . (by chi-square test) medical application climacteric disorder surgically or drug-induced menopause premature ovarian failure p = . (by chi-square test) note: *p , . vs gel (by one-way anova followed by scheffe’s f-test). table usability and compliance group (tablet) n = group (patch) n = group (gel) n = usability: “what is the usability of your estrogen formula?” “favorable” “rather favorable” “neutral” “rather unfavorable” “unfavorable” p = . (by kruskal–wallis test) compliance: “how often do you forget your medication per month?” “never” “once” “twice” “three times” “more than three times” p = . (by kruskal–wallis test) table beauty care practices and exercise habits group (tablet) n = group (patch) n = group (gel) n = beauty care practices: “how often do you put on makeup?” “every day” “sometimes” “rarely” “never” p = . (by kruskal–wallis test) exercise habits: “how often do you engage in mild exercise?” “once a week” “once a month” “once per three months” “never” p = . (by kruskal–wallis test) submit your manuscript | www.dovepress.com dovepress dovepress estrogen gel and beauty care in te rn a tio n a l j o u rn a l o f w o m e n 's h e a lth d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -m a y- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of women’s health : . . tablet patch gel group group group group group group beauty care practices beauty care practices high: “every day”, “sometimes” high: “once a week”, “once a month” low: “rarely”, “never” low: “once per three months”, “never” sports habits sports habits high high high . ( . ) . ( . ) . ( . ) low low- high low age (years) mean (se) p = . (by one-way anova) (n = ) (%) (n = ) (n = ) . . . . . . . figure relationship between the level of beauty care and choice of estrogen formulations. note: p = . , ordinary logistic regression analysis. b a priority subjective impression smell sticky feeling spreadability irritancy smell sticky feeling spreadability irritancy figure estimate of priority and subjective impression in transdermal gel users. priority (a) and subjective impression (b) in transdermal gel users were assessed as described in the “materials and methods” section. notes: *p , . ; **p , . (steel–dwass test). submit your manuscript | www.dovepress.com dovepress dovepress takeda et al in te rn a tio n a l j o u rn a l o f w o m e n 's h e a lth d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -m a y- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of women’s health : irritation and poor adhesion. the biggest disadvantage is that transdermal administration is bothersome because of its unfamiliar mode of administration. most drugs are admin- istered orally and the transdermal route is only used in a minority. our data showed that there were no differences in the usability and compliance of medicines among the estro- gen formulations, so the bothersome handling of transdermal administration did not seem to be a burden to hrt users. in general, women are more familiar with beauty care practices than men and our data showed that only % of hrt users had a low-frequency makeup habit. it is possible that most of the women could handle the transdermal formulas easily, given their similarity to cosmetics. it has been previously reported that hrt use and the level of beauty care practices were positively associated. women might expect anti-aging effects such as maintain- ing a youthful appearance and skin tone from hrt use. because of its unique commonality with cosmetics, we expected that transdermal gel users might show high levels of beauty care practices. contrary to our expectation, we could not detect a difference in beauty care practice levels between those using different estrogen formulas (table ). more than half of the women reported that they practice beauty care every day, so we speculated that we could not detect a difference because of their strong preference for makeup. we further divided the high-frequency beauty care practice group into two groups according to exercise habits (figure ). exercise habits might reflect a positive mental attitude and women might expect anti-aging effects from exercise such as maintaining a youthful body and a good shape. group (high in beauty care practices, high in exercise habits) seemed to be more active than group (high in beauty care practices, low in exercise habits) in terms of their beauty care practices. possible avenues for future research include more detailed questions about beauty care practices such as usage of antiwrinkle cream, facial treatment, and cosmetic surgery might be useful to deepen our understanding of this issue. concerning the compliance of patients using the different formulas, it would also be interesting to measure the plasma levels of estradiol with the use of the different formulas. our data suggested that “sticky feeling” is the biggest challenge for the transdermal gel formula. in japan, we can use only one type of transdermal β-estradiol gel under the national health insurance system. two newer types of transder- mal estrogen formulas, transdermal spray and topical emulsion, are clear and not sticky. , introduction of these formulas to japan would potentiate the usage of transdermal estrogen. conclusion our data suggested that the level of attention to beauty care plays some role in the choice of estrogen formulation. trans- dermal gel formula was acceptable in view of the cosmetic aspects. “sticky feeling” is the biggest challenge for the transdermal gel formula. disclosure the authors report no conflicts of interest in this work. low irritancy low sticky feeling moderate very good fairly poor fairly good usability subjective impression good smell good spreadability . . − . − . . . − . − . . − . figure correspondence analysis of the subjective impression and the usability of transdermal gel. notes: • (closed circle): subjective impression; ♦ (closed diamond): usability. submit your manuscript | www.dovepress.com dovepress dovepress estrogen gel and beauty care in te rn a tio n a l j o u rn a l o f w o m e n 's h e a lth d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -m a y- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of women’s health publish your work in this journal submit your manuscript here: http://www.dovepress.com/international-journal-of-womens-health-journal the international journal of women’s health is an international, peer- reviewed open-access journal publishing original research, reports, reviews and commentaries on all aspects of women’s healthcare includ- ing gynecology, obstetrics, and breast cancer. subject areas include: chronic conditions (migraine headaches, arthritis, osteoporosis); endocrine and autoimmune syndromes; sexual and reproductive health; psychological and psychosocial conditions. the manuscript management system is completely online and includes a very quick and fair peer-review system. visit http://www.dovepress.com/ testimonials.php to read real quotes from published authors. international journal of women’s health : references . cobin rh, futterweit w, ginzburg sb; for aace menopause guidelines revision task force. american association of clinical endocrinologists medical guidelines for clinical practice for the diagnosis and treatment of menopause. endocr pract. ; : – . . north american menopause society. estrogen and progestogen use in peri- and postmenopausal women: july position statement of the north american menopause society. menopause. ; : – . . panay n, kalu e. management of premature ovarian failure. best pract res clin obstet gynaecol. ; : – . epub december , . . nelson hd. commonly used types of postmenopausal estrogen for treatment of hot flashes: scientif ic review. jama. ; : – . . balfour ja, heel rc. transder mal estradiol. a review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in the treatment of menopausal complaints. drugs. ; : – . . fauconnier a, ringa v, delanoë d, falissard b, bréart g. use of hormone replacement therapy: women’s representations of menopause and beauty care practices. maturitas. ; : – . . hunter ms, o’dea i, britten n. decision-making and hormone replacement therapy: a qualitative analysis. soc sci med. ; : – . . http://www.wma.net [homepage on the internet] world medical association. declaration of helsinki ethical principles for medical research involving human subjects. [ pages] available from http:// www.wma.net/en/ publications/ policies/b / c.pdf. accessed january , . . frenkel y, kopernik g, lazer s, et al. acceptability and skin reactions to transdermal estrogen replacement therapy in relation to climate. maturitas. ; : – . . buster je, koltun wd, pascual mlg, day ww, peterson c. low-dose estradiol spray to treat vasomotor symptoms. obstet gynecol. ; : – . . simon ja. estradiol in micellar nanoparticles: the efficacy and safety of a novel transdermal drug-delivery technology in the management of moderate to severe vasomotor symptoms. menopause. ; : – . submit your manuscript | www.dovepress.com dovepress dovepress dovepress takeda et al in te rn a tio n a l j o u rn a l o f w o m e n 's h e a lth d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -m a y- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / http://www.dovepress.com/international-journal-of-womens-health-journal http://www.dovepress.com/testimonials.php http://www.dovepress.com/testimonials.php http://www.wma.net http://www.wma.net/en/ publications/ policies/b / c.pdf http://www.wma.net/en/ publications/ policies/b / c.pdf www.dovepress.com www.dovepress.com www.dovepress.com www.dovepress.com publication info : nimber of times reviewed: emory law journal | emory university school of law | atlanta, ga | journals | emory university school of law home search browse collections my account about digital commons network™ skip to main content home about faq my account home > journals > emory law journal follow founded in , the emory law journal was the first journal sponsored by emory university school of law. originally titled the journal of public law, the journal specialized in public law fields. in , the editorial board changed the name of the journal to the emory law journal and pledged to widen the editorial scope of the journal to include matters of general law, while maintaining an emphasis 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price. we show how this failure of the law of iterated expectations for average belief can help understand the role of higher-order beliefs in a fully rational asset pricing model. ‘‘… professional investment may be likened to those newspaper com- petitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average pre- ferences of the competitors as a whole; so that each competitor has to pick, not those faces which he himself finds prettiest, but those which he thinks likeliest to catch the fancy of the other competitors, all of whom are looking at the problem from the same point of view. it is not a case of choosing those which, to the best of one’s judgement, are really the prettiest, nor even those which average opinion genuinely thinks the prettiest. we have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. and there are some, i believe, who practise the fourth, fifth and higher degrees.’’ keynes ( ), page . we are grateful to seminar participants at lse, bank of england, imf, kellogg, stanford, the chicago accounting theory conference, the gerzensee finance meetings, and to participants at the afa san diego meetings and our discussant andrei shleifer for their comments. we thank mehul kamdar for capable research assistance. we are grateful to the editor, maureen o’hara, and a referee for their guidance. address correspondence to hyun song shin, princeton university, bendheim center for finance, nj , or e-mail: hsshin@princeton.edu � the author . published by oxford university press on behalf of the society for financial studies. all rights reserved. for permissions, please email: journals.permissions@oxfordjournals.org. doi: . /rfs/hhj advance access publication march , mailto:hsshin@princeton.edu mailto:permissions@oxfordjournals.org keynes ( ) introduced the influential metaphor of financial markets as a beauty contest. an implication of the metaphor is that an under- standing of financial markets requires an understanding not just of market participants’ beliefs about assets’ future payoffs, but also an understanding of market participants’ beliefs about other market participants’ beliefs, and higher-order beliefs. judging by how often the above passage from keynes is quoted in academic and nonacademic circles, many people find the metaphor highly suggestive. yet the theoretical literature on asset pricing has, until recently, failed to develop models that validate the role of higher- order beliefs in asset pricing. the purpose of our article is to illuminate the role of higher-order expectations in an asset-pricing context, and thereby to explore the extent to which keynes’s beauty-contest metaphor is valid as a guide for thinking about asset prices. higher-order expectations do not make an appearance in standard competitive asset pricing models with a representative investor. asset prices in such settings reflect the discounted expected value of payoffs from the asset, suitably adjusted for risk. since we believe that the beauty- contest phenomenon alluded to above is consistent with competitive asset pricing models, our explanation must include an account of why asset prices in a competitive market may fail to reflect solely the discounted expected payoffs. a key feature of the representative investor model of asset prices that makes higher-order expectations redundant is the martingale property of asset prices. the price of an asset today is the discounted expected value of the asset’s payoff stream with respect to an equivalent martingale measure, conditional on the information available to the representative individual today. this allows the folding back of future outcomes to the present in coming up with today’s price. an implication of the martingale property in a representative individual economy is the law of iterated expectations, in which the representative investor’s expectation today of his expectation tomorrow of future payoffs is equal to his expectation today of future payoffs. but if there is differential information between investors so that there is some role for the average expectations about payoffs, the folding back of future outcomes to the present cannot easily be achieved. in general, average expectations fail to satisfy the law of iterated expectations. it is not the case that the average expectation today of the average expectation tomorrow of future payoffs is equal to the average expectation of future payoffs. the key observation in this article is not only that the law of iterated expectations fails to hold for average opinion when there is differential information, but that its failure follows a systematic pattern that gives rise to features of interest in finance. suppose that an individual has access to both private and public information about an asset’s payoffs, and they are of equal value in the review of financial studies / v n predicting the asset’s payoffs. in predicting the asset’s payoffs, the indi- vidual would put equal weight on private and public signals. now sup- pose that the individual is asked to guess what the average expectation of the asset’s payoffs is. since he knows that others have also observed the same public signal, the public signal is a better predictor of average opinion; he will put more weight on the public signal than on the private signal. thus if individuals’ willingness to pay for an asset is related to their expectations of average opinion, then we will tend to have asset prices overweighting public information relative to the private informa- tion. thus any model where higher-order beliefs play a role in pricing assets will deliver the conclusion that there is an excess reliance on public information. this bias toward the public signal is reminiscent of the result in morris and shin ( ), where the coordination motive of the agents induces a disproportionate role for the public signal. although there is no explicit coordination motive in the rational expectations equilibrium, the fact that the public signal enters into everyone’s demand function means that it still retains some value for forecasting the aggregate demand above and beyond its role in estimating the liquidation value. another way of expressing this is to say that, whereas the noise in the individual traders’ private signals get ‘‘washed out’’ when demand is aggregated across traders, the noise term in the public signal is not similarly washed out. thus, the noise in the public signal is still useful in forecasting aggregate demand and, hence, the price. grossman ( ), hellwig ( ), and diamond and verrecchia ( ) showed how equilibrium can be constructed when prices play an informa- tional role in competitive asset markets with differential information. admati ( ) extended the analysis to a multiasset setting and showed the importance of correlations between the traders’ prediction errors in determining asset returns, over and above the traditional emphasis on the correlation of asset returns. our main focus, however, is on the dynamic, multiperiod asset pricing context with a single risky asset. do asset prices reflect aver- age opinion, and average opinion about average opinion, in the manner that keynes suggests? our answer is a resounding ‘‘yes.’’ we look at a version of the dynamic, noisy rational expectations asset pricing model, of the type developed by singleton ( ), brown and jennings ( ), grundy and mcnichols ( ), and he and wang ( ). much of the early literature has focussed on trading volume and has not highlighted the role of higher-order beliefs in asset prices our purpose is to show how higher-order beliefs are reflected in asset wang ( ) examines a model where some traders are strictly better informed than the rest, so that the informed traders’ information is a sufficient statistic for the economy. beauty contests and iterated expectations prices. bacchetta and van wincoop ( , ) have also examined higher-order beliefs in asset pricing, and we return to a more detailed description of the related work in the final section. in our model, there is a single risky asset that will be liquidated at date t þ but is traded at dates to t by overlapping generations of traders, who trade when young and consume when old. our assumption of overlapping generations of traders is intended to accentuate the impor- tance of short-run price movements for traders. even for long-lived traders, if they have a preference for smoothing consumption over time, they will care about short-run price movements, as well as the underlying fundamental value of the asset at its ultimate liquidation. for example, one reason for short horizons is that individuals’ funds are managed by professionals, and inefficiencies resulting from the agency problem give rise to short horizons [allen and gorton ( )]. in the concluding section (section ), we discuss some of the existing literature with similar conclusions. the assumption of overlapping generations is used as a device to throw into sharper relief this concern for short-run prices. our motivation for making this assumption is to attempt to capture some of the intuition behind keynes’s beauty-contests metaphor, in which traders are motivated to second- and third-guess other traders in order to profit from short-run price movements. our assumption of overlapping genera- tions of traders makes it similar to the short-lived trader version of the model examined in brown and jennings ( ). by developing a framework of analysis that can accommodate higher- order beliefs, we show how keynes’s beauty-contest metaphor can be formalized in our setting, and how it has a direct impact on asset prices. there are two themes to our results. . first, the mean path of prices will, in general, depart from the market consensus of the expected fundamental value of the asset. even though prices result from forward-looking expectations, there is no unravelling of the iterated expectations to force prices to be the same as consensus expectations of fundamentals. to the extent that the mean price path deviates from the consensus liquidation value, we have elements of a bubble. . second, prices in a beauty contest react much more sluggishly to changes in the fundamental value of the asset. prices exhibit inertia, although the early literature did not address higher-order beliefs explicitly, brown and jennings ( ) did focus on asset pricing issues, showing that, in noisy rational expectations equilibria (unlike in a martingale asset pricing world), past prices convey information to market participants. he and wang ( ) note (in the discussion following their lemma ) how their finite horizon assumption allows higher-order expectations to be reduced to lower-order expectations in solving the model. our purpose in this article is to show how and why equilibrium price relationships in dynamic noisy rational expectations models, such as those of brown and jennings ( ) and he and wang ( ), reflect the higher-order beliefs intuition of keynes’ beauty contest metaphor. the review of financial studies / v n or ‘‘drift.’’ in particular, prices react more sluggishly to changes in fundamentals than does the consensus fundamental value. even as traders update their views of the fundamental value, the price does not react as much. the second bullet point is reminiscent of the literature on the apparent underreaction of asset prices over short horizons. an enduring empirical regularity that has received much attention is that, over hor- izons of perhaps to months, there is a predictable component to asset returns where asset prices exhibit momentum. in a beauty contest, prices exhibit the same outward sign of momentum or drift. thus, even though prices are forward-looking expectations of future liquidation, we find considerable inertia in such forward-looking expectations. the insights of this article are relevant beyond the asset pricing application. the macroeconomic literature on forecasting the fore- casts of others, as initiated by townsend ( , ) and phelps ( ) and developed by sargent ( ) and others, looked at dynamic models where agents follow linear decision rules, but their choices depend on others’ choices and their heterogeneous expectations about future realizations of economic variables. as a consequence, forward-looking iterated average expectations matter. the cara- normal noisy rational expectations asset prices of this article inherit both the linear decision rules and the forward-looking iterated average expectations. one insight highlighted in this article is that forward- looking iterated average expectations exhibit inertia. this is relevant for the recently renewed interest in heterogeneous expectations in macroeconomics. explicit solutions for such macroeconomic models are rarely possible, due to their complexity. in contrast, the questions addressed in our article are sufficiently simple for us to derive a number of explicit results. these results may have some bearing on the general problem of the role of iterated expectations in differential information economies. before launching into our asset pricing model, we provide some background by examining the abstract properties of higher-order expectations in section . our main asset pricing analysis follows this initial discussion. we conclude in section by discussing the robustness of our model to changes in assumptions (in particular, relaxing the short-lived trader assumption) and relating our results to some of the recent literature. there is a very large empirical literature. barberis, shleifer, and vishny ( ) gather together some of the evidence. for example, amato and shin ( ), hellwig ( ), stasavage ( ) and woodford ( ). pearlman and sargent ( ) show that some cases of such problems reduce to the common knowledge case. beauty contests and iterated expectations . background for any random variable �, let eitð�Þ be player i’s expectation of � at date t; write etð�Þ for the average expectation of � at time t, and write e*t ð�Þ for the public expectation of � at time t (i.e., the expectation of � conditional on public information only; in a partition model, this would be conditional on the meet of players’ information). we know that individual and public expectations satisfy the law of iterated expectations: eit ei;tþ �ð Þ � � ¼ eit �ð Þ and e*t e * tþ �ð Þ � � ¼ e*t �ð Þ: but the analogous property for average expectations will typically fail under asymmetric information. in other words, we will typically have et etþ �ð Þ � � ¼ et �ð Þ: this is most easily seen by considering the case where there is no learning over time. suppose � is distributed normally with mean y and variance � . each agent i in a continuum observes a signal xi ¼ �þ"i , where "i is distributed in the population with mean and variance � . suppose that this is all the information available at all dates. then we may drop the date subscripts. now observe that ei �ð Þ¼ �y þ�xi �þ� e �ð Þ¼ �y þ�� þ� ei e �ð Þ � � ¼ �y þ�ei �ð Þ �þ� ¼ �y þ� �yþ�xi �þ� � � �þ� ¼ � � �þ� � � ! y þ � �þ� � � xi e e �ð Þ � � ¼ � � �þ� � � ! y þ � �þ� � � � iterating this operation, one can show that the review of financial studies / v n e k �ð Þ¼ � � �þ� � �k ! y þ � �þ� � �k �: ð Þ note that ( ) the expectation of the expectation is biased toward the public signal y; that is, sign e e �ð Þ � � � e �ð Þ � � ¼ sign y � e �ð Þ � � ; and ( ) as k ! ; ekð�Þ! y. putting back the time subscripts, we have et etþ �ð Þ � � ¼ � � �þ� � � ! y þ � �þ� � � � ¼ �y þ�� þ� ¼ et �ð Þ: and et etþ ……et� et� �ð Þ � �� ¼ � � �þ� � �t�t ! y þ � �þ� � �t�t �: now suppose that there is an asset that has liquidation value � at date t . suppose—in the spirit of the keynes beauty contest—that the asset is priced according to the asset pricing formula pt ¼ et ptþ ð Þ: ð Þ then we would have pt ¼ � � �þ� � �t�t ! y þ � �þ� � �t�t �: ð Þ given the realization of the public signal, the period t price is biased toward the public signal relative to fundamentals. there is an alternative way to present the argument that is revealing, and which also anticipates our general argument later. let us recast the inference problem for individual i in matrix form as follows. ei y � � ¼ � �þ� � �þ� " # y xi � averaging over individuals, property ( ) does not hold for all distributions; one can construct examples where it fails to hold. however, property ( ) holds independently of the normality assumption; this is, for any random variable and information system with a common prior, the average expectation of the average expectations… of the random variable converges to the expectation of the random variable conditional on public informa- tion [see samet ( )]. beauty contests and iterated expectations e y � � ¼ � �þ� � �þ� " # y � � thus, the average belief operator e can be represented by the transition matrix of a two-state markov chain defined over the state space fy;�g. note that the public signal y is an absorbing state in this markov chain, since once the system has entered the state, it never leaves. then, higher- order average expectations can be obtained by iteration of the transition matrix. e k y � � ¼ � �þ� � �þ� " #k y � � ¼ � � �þ� � �k � �þ� � �k " # y � � ! y y � as k ! the weight on the true value of � is the probability of being in a transitory state in the markov chain. hence, as the order of beliefs increases, the true value of � receives less and less weight. we will now show how this markov chain insight can be used in the main analysis. so far, we have given no justification for asset pricing formula ( ), other than an appeal to the authority of keynes. we would like to describe an asset pricing model that generates the asset pricing formula in equation ( ), or something like it, and deals with the issue of learning from prices. we will turn to this problem now. . asset prices time is discrete and is labelled by the set f ; ; � � � ; t; t þ g. there is a single risky asset that will be liquidated at date t þ but is traded at dates to t . the liquidation value � of the asset is determined before trading at date and is a normally distributed random variable with mean y and variance =�. once � is determined at date , it remains fixed until the asset is liquidated at date t þ (figure ). there are over- lapping generations of traders who each live for two periods. a new generation of traders of unit measure is born at each date t and is indexed by the unit interval [ , ]. at date t, when the traders are young, they trade the asset to build up a position in the asset but do not consume. we assume that they have sufficient endowments so that they are never wealth constrained. in the next period (at date t þ ), when they are the review of financial studies / v n old, they unwind their asset holding and acquire the consumption good, consume, and die. thus, at any trading date t, there is a unit mass of young traders and a unit mass of old traders. our assumption of overlapping generations of traders is intended to accentuate the importance of short-run price movements for traders. even for long-lived traders, if they have a preference for smoothing consumption over time, they will care about short-run price movements, as well as the underlying fundamental value of the asset at its ultimate liquidation. the assumption of overlapping generations is used as a device to throw into sharper relief this concern for short-run prices. our motivation for making this assumption is to attempt to capture some of the intuition behind keynes’s beauty-contests metaphor, in which traders are motivated to second- and third-guess other traders in order to profit from short-run price movements. our assumption of overlapping genera- tions of traders makes it similar to the short-lived trader version of the model examined in brown and jennings ( ). when each new trader is born, they do not know the true value of �. however, for a trader i born at date t, there are two sources of informa- tion. first, the full history of past and current prices are available, including the ex ante mean y of �. second, this trader observes the realization of a private signal xit ¼ �þ"it in contrast, other authors such as he and wang ( ) have examined the case where traders only consume at the terminal date and trade up to that date. we discuss this case further below. figure path of fundamental value beauty contests and iterated expectations where "it is a normally distributed noise term with mean and variance =�. we assume that the noise terms f"itg are i.i.d. across individuals i and across time t. there is no other source of information for the trader. in particular, the private signals of the previous generation of traders are not observable. hence, the information set of trader i at date t is y; p ; p ; � � � ; pt; xitf g where pt is the price of the asset at date t (figure ). as a convention, we take ptþ ¼ �. all traders have the exponential utility function uðcÞ¼�e�c� defined on consumption c when they are old. the parameter � is the reciprocal of the absolute risk aversion, and we shall refer to it as the traders’ risk tolerance. finally, in each trading period, we assume that there is an exogenous noisy net supply of the asset, st, distributed normally with mean and precision �t. the supply noise is independent over time, and independent of the fundamentals and the noise in traders’ information. the modeling device of noisy supply is commonly adopted in rational expectations models so as to prevent the price from being a fully revealing signal of the fundamentals. noisy supply is sometimes justified as the result of noise traders or in terms of the subjective uncertainty facing traders on the ‘‘free float’’ of the asset that is genuinely available for sale [see easley and o’hara ( ), footnote , page ]. one potentially unsatisfactory feature of our setup is the feature that random net supplies are independent draws over time. when there are overlapping generations of traders, such an assumption is figure private information the review of financial studies / v n not always a natural one. independence could be justified by means of the following scenario. at each date, a group of noise traders arrive on the market, trade the asset, and then automatically reverse their trade at the next date. the amounts traded by these groups of noise traders are random and insensitive to price. thus, at any date, there are four groups in the market who trade. these are the new and old groups of noise traders and the new young generation who wish to buy the asset and the old generation who sell what they purchased at the previous date. the important feature is that the uncertainty facing the young traders is the new net supply, and this new net supply is an independent gaussian random variable. clearly, the interpretation given above is somewhat contrived, but we advance it merely as a modeling device that serves the purpose of pre- venting prices being fully revealing, and preserving the independence of the supply shocks over time, so as to aid tractability of the analysis. our assumption that noisy supply is independent over time can be seen as a special case of he and wang ( ), who assumed that supply follows a gaussian ar( ) process. brown and jennings ( ) assumed that noisy supply follows a random walk. the role of iterated expectations can be brought out in our context. begin with a trader i who trades at the final trading date t . the trader’s demand for the asset is linear due to constant absolute risk aversion and normally distributed payoffs and is given by � varit �ð Þ eit �ð Þ� ptð Þ ð Þ where eitð�Þ is the expectation of � conditional on trader i’s information set at date t , and varitð�Þ is the conditional variance of � with respect to the same information set. because the traders have private signals that are i.i.d. conditional on �, the conditional variances fvaritð�Þg are identical across traders, and we denote by vartð�Þ this common condi- tional variance across traders. summing condition ( ) across traders, the aggregate demand at date t is given by � vart �ð Þ et �ð Þ� pt � � ð Þ where etð�Þ is the average expectation of � at date t . market clearing then implies that pt ¼ et �ð Þ� vart �ð Þ � st ð Þ beauty contests and iterated expectations the price at the previous date t � can be derived from an analo- gous argument, bearing in mind that young traders who trade at date t � care about pt rather than the final liquidation value of the asset, since their own consumption is related to pt . the price at date t � is given by pt� ¼ et� ptð Þ� vart� ptð Þ � st� ð Þ substituting equation ( ) into equation ( ), and noting that et� ðstÞ¼ , we have the following expression for price at t � . pt� ¼ et� et �ð Þ� vart� ptð Þ � st� ð Þ this is a recursive relationship that can be iterated further back in time. thus, the price at date t is given by pt ¼ etetþ � � �et �ð Þ� vart ptþ ð Þ � st ð Þ the price at date t is the average expectation at date t of the average expectation at the next trading date, etc., of the final liquidation value �. expressions such as equation ( ) should encourage us that we have an approach that may enable us to address keynes’s beauty-contest meta- phor. however, we need to delve deeper into the consequences of the iterated expectations in order to make any headway. in particular, we would like to address two questions. . is there any systematic difference between the price pt and the consensus value of the fundamentals given by etð�Þ? the term ‘‘systematic’’ is important here, since the noisy supply will mean that the actual realization of the price is noisy. rather, the question is whether, averaging over the noisy realizations of the supply, the price deviates systematically from the average expectations of the fundamentals. if so, we have elements of a bubble to the extent that the market price does not reflect the consensus about the true value of the fundamentals. . how quickly does the price adjust to the shift in fundamentals at date ? does the price adjust rapidly to take account of the new fundamental value, or is there inertia or ‘‘drift’’ in the path followed by prices? in particular, how does the speed of the adjustment of the price path differ from the speed of the adjustment of the average expectations of fundamentals? the review of financial studies / v n we will answer these questions by means of three propositions. figure illustrates our results. the line labelled as pt is the mean of the price path with respect to the noisy realizations of supply. the line labelled as etð�Þ is the mean path of the average expectation of � with respect to the noisy realizations of supply. the mean price path deviates systematically from the mean path of average expectations, and the price path lies further away from the true value than the average expectations. so, prices not only fail to reflect the consensus on true fundamental value, but are further away from the true value. also, the initial adjustment in price at date is too sluggish, failing to reflect the true extent of the shift in fundamentals from y to �. thereafter, the price does adjust, but slowly. it only catches up with the average expectations of fundamentals at the last trading date. the line labelled by qt is the path followed by the naive iterated expectation given by equation ( ) in section that ignores the information given by prices. the mean path for price lies between this path and the mean path for average expectations. one of our results below identifies a limiting case for when the mean price path coincides with the naive iterated expectations path. in what follows, we denote by esð�Þ the expectation with respect to the noisy supply terms fstg. the propositions below are proved in appendix a. proposition . for all t < t es pt ��j jð Þ > es et �ð Þ�� it is only at the final trading date, t, that we have esðptÞ¼ es etð�Þ � � . figure mean of time paths of pt and �etðqÞ beauty contests and iterated expectations prices deviate systematically from the average expectations of the fundamental value of the asset. even though price is a forward-looking expectation of the final liquidation value, the beauty-contests element of the problem prevents the folding back of the final liquidation value into prices. the proof of proposition in appendix a reveals that the root cause of the deviation of price from the average expectation of the fundamental value can be traced to the the excess weight given to past prices and the ex ante mean of � in the determination of price, where ‘‘excess’’ is defined relative to the statistically optimal forecast of the fundamental value �. arbitrage by short-lived traders will not pull the price back toward fundamentals. this is because the short-lived traders are risk averse, and their private signals are imprecise estimates of the true value. however, as the traders become less risk averse, or when their private signals become more precise, their demands become more aggressive (more sensitive to price), rendering prices to be more precise signals of the fundamentals. in the limit as the traders become risk neutral, or when the signal becomes infinitely precise (so that the conditional variance of � tends to zero), the demand curves become horizontal, and prices become fully revealing. however, short of this extreme case, there is some divergence between the price and the fundamental value. proposition . there exist weights f�tg with < �t < �t� < � � � < � < � < such that es ptð Þ¼ �ty þ ��tð Þ� prices exhibit inertia, or ‘‘drift’’ in adjusting to the fundamental value �. taken together with proposition , this implies that after fundamentals are realized at date , the price does not adjust sufficiently. instead, it approaches the true fundamental value slowly in incremental steps. such a price path would have many outward appearances of short-run momentum in prices, as documented in many empirical studies. proposition . let qt be defined as qt ¼ � � �þ� � �t�tþ ! y þ � �þ� � �t�tþ � then, as � ! , we have es ptð Þ! qt the review of financial studies / v n the sequence fqtg is the naive iterated exectations that we encoun- tered in equation ( ) in section . as traders become more and more risk averse, the mean price path approaches the naive iterated expecta- tions where prices do not figure at all in the inference about the fundamentals. as we will see below, the intuition for the result lies in the fact that, as traders become more risk averse, they become less aggressive in setting their demand functions, thereby making prices less informative. in the limit, prices cease to have any information value at all. we will argue for our results by presenting a framework that uses the intuitions from the markov chain argument that we saw in section . we begin with the expression for pt in terms of the iterated average expectations. pt ¼ etetþ � � �et �ð Þ� vart ptþ ð Þ � st from joint normality of the random variables, eitetþ � � �etð�Þ is a linear combination lðxi; y; p ; p ; � � � ; ptÞ of random variables in i’s information set. taking averages across i; etetþ � � �etð�Þ is given by lð�; y; p ; p ; � � � ; ptÞ—the same linear combination in which xi is replaced by �. thus, pt can be written as a linear function ltð�Þ of y; �; st and past prices. p ¼ l y;�; s ð Þ p ¼ l y;�; s ; p ð Þ .. . pt ¼ lt y;�; st; p ; p ; � � � ; ptð Þ then p ¼ l ðy;�; s ; l ðy;�; s ÞÞ, which is a linear function of y;�; s and s . by recursive substitution, pt can be expressed as a linear combi- nation of fy;�; s ; s ; � � � ; stg. thus, p ¼ � y þ� �� s p ¼ � y þ� �� s � s .. . pt ¼ �t y þ�t�� t s � t s �� tt st ð Þ let us write equation ( ) in matrix form as follows. beauty contests and iterated expectations p .. . pt ¼ � .. . �t y þ � .. . �t �� .. . . . . t � � � tt s .. . st the matrix � of coefficients f stg is lower triangular and, hence, inver- tible. multiplying both sides by the inverse and rearranging, we can obtain random variables f ; ; � � � ; tg that are independent conditional on �. � � ð Þ p �� yð Þ � ð Þ � ¼ �� s � ð Þ � .. . t � � ð Þ t p �� yð Þþ�� þ � ð Þ tt pt ��t yð Þ � ð Þ t � þ��þ � ð Þ tt �t ¼ �� st � ð Þ t � þ�� þ � ð Þ tt �t where ð� Þ st denotes the ðs; tÞth entry of �� . here, t can be seen as a random variable that is a noisy signal of � conveyed by price pt. t is normally distributed with mean �, and some given precision �t. the precision �t of this signal is, of course, endogenously determined in equilibrium, and a full solution of the rational expectations equili- brium will entail solving for the precisions of all signals t. however, for our qualitative results below, a full solution turns out not to be necessary. by using the transformed variables, trader i’s information set at date t can be written as fxi; y; ; ; � � � ; tg. the expectation of � conditional on this information set is given by eit �ð Þ¼ �xi þ�y þ pt i¼ �i i � þ�þ pt i¼ �i ð Þ now, consider the vectors z and zit where z ¼ y .. . t � zit ¼ y .. . t xit the review of financial studies / v n (the difference between z and zit is that the � is replaced by xit). denote by eitz the conditional expectation of z according to i’s information set at date t. that is, eitz ¼ eity eit .. . eit t eit� from equation ( ), and since s is either known at date t or is a random variable centred on �, we can write down a stochastic matrix bt such that eitz ¼ btzit ð Þ the bt matrix will play a crucial role in our analysis. this matrix can be depicted as follows. where i is the identity matrix of order t þ ; rt is a ðt � t þ Þ�ðt þ Þ matrix and rt is a t � t þ column vector given by rt ¼ �t � t � � � �tt �t � t � � � �tt .. . .. . .. . �t � t � � � �tt ; rt ¼ �t �t .. . �t beauty contests and iterated expectations where �t ¼ � �þ pt i¼ �i þ� ; �kt ¼ �k �þ pt i¼ �i þ� ; �t ¼ � �þ pt i¼ �i þ� are, respectively, the relative precisions of the ex ante mean y, the date k price signal at date t, and the private signal xit. all other entries in bt are zero. taking the average over i of both sides of equation ( ), etz ¼ btz ð Þ since the mean of all the fxig gives �. meanwhile, trader i’s expectation of etz at date t � is given by ei;t� etz ¼ ei;t� btz ¼ btei;t� z ¼ btbt� zi;t� taking averages across i on both sides, et� etz ¼ btbt� z ð Þ note the reversal of the order of the belief operator when it is converted to the equivalent matrix operation. the intuition for this reversal is the fact that the date t average expectation must be a linear combination of random variables realized up to date t. however, since z contains all random variables up to date t , the average expectation at date t must put zero weight on any random variable realized later than date t. iterating the relationship in equation ( ), we have etetþ � � �et z ¼ bt � � �btþ btz ¼ b*t z ð Þ where b*t � bt � � �btþ bt since the bottom entry of z is �, the bottom entry of b*t z thus gives the iterated average expectation of �. the matrix bt can be interpreted as the transition matrix of a markov chain defined on the set fy; ; � � � ; t;�g. this suggests that we can use the markov chain argument with absorbing states used in section to evaluate iterated expectations. however, we can see from equation ( ) that the transition matrix used in each step of the iteration is different. in other words, we have a nonhomogenous markov chain where the the review of financial studies / v n transition probabilities change over time. from equation ( ) we can track the transition probabilities. we note the following features of the markov chain defined by the sequence of transition matrices bt; bt� ; � � � ; b . . the state y is an absorbing state of this chain. we can see from equation ( ) that, once the system has entered this state, it never emerges. therefore, it gathers more probability mass with each transition. . the price signals t are ‘‘temporary absorbing states’’ in the sense that initially they act like absorbing states, but after t � t periods in the transition, they suddenly become transient states by giving up all their probability mass to other states let us denote by bt the last row of bt, and denote by b * t the last row of b*t , where bt ¼ �t;� t;� t; � � � ;�tt; ; � � � ; ;�t½ � b*t ¼ � * t ;� * t;� * t; � � � ;� * tt; ; � � � ; ;� * t � � let us reiterate the following properties. lemma . for all t; esðptÞ¼ b*t z and esðetð�ÞÞ¼ btz. in other words, the mean price path can be calculated using fb*tg while the mean path for etð�Þ can be calculated using fbtg. lemma follows directly from equations ( ) and ( ). it shows the usefulness of the matrices b*t and bt. the aggregate demand for the risky asset at date t is given by � vart ptþ ð Þ et ptþ ð Þ� pt � � ¼ � vart ptþ ð Þ etetþ � � �et �ð Þ� pt � � ¼ � vart ptþ ð Þ b*t z � pt � � market clearing then implies that pt ¼ b*t z � vart ptþ ð Þ � st ¼ �*t y þ xt i¼ �*it t þ� * t �� vart ptþ ð Þ � st since t is the sum of � and a noise term that depends on the supply noise at date t, and since the sum of elements in b*t must sum to , we can write price pt in general as beauty contests and iterated expectations pt ¼ �*t y þ �� * t � � �� t s � t s �� ttst ð Þ the following pair of lemmas are proved in appendix a. lemma . < �*t < � � � < �*t < �*t� < � � � < � * < . lemma . for t < t , we have �*t > �t. at date t; � * t ¼ �t . then proposition follows from lemma by setting �t ¼ �*t . thus, equilibrium prices exhibit inertia or ‘‘drift’’ in adjusting to the new fundamentals. we can then prove proposition , which shows that the mean time path of prices is further away from fundamentals than the mean time path of etð�Þ. using an exactly analogous argument to that used to derive equation ( ), we can write down the time path of average expectations of the fundamentals etð�Þ as e �ð Þ¼�̂ y þ �̂ �� ̂ s e �ð Þ¼�̂ y þ �̂ �� ̂ s � ̂ s .. . et �ð Þ¼�̂t y þ �̂t�� ̂t s � ̂t s �� ̂tt st ð Þ then lemma shows that �̂t < �t for all t < t , but �̂t ¼ �t . this proves proposition . the intuition for why �̂t < �t lies in the fact that in the markov chain defined by the matrices fbtg, the state y is an absorbing state. the price pt is determined by the iterated average expectations of �, and hence in the markov chain, the probability of being absorbed at y is large, and certainly much larger than the one shot transition implied by the mean path of etð�Þ. thus, the mean price path gives a higher weight to history than does the mean path of etð�Þ. this explains both the greater sluggishness of prices and the systematic deviation of price from average belief of fundamentals. in appendix b, we present the solution for the two-trading-period version of our model that uses more direct methods that have much in common with the earlier literature. as well as confirming the general form of the solution identified so far, it also serves to show the respective role of the informational parameters in the solution. in particular, as the precision of the private signal becomes small, or when the noise in the supply becomes large, prices become less precise signals of the fundamen- tal value, and the mean price path follows the naive iterated expectations given by equation ( ) in section that ignores the information given by prices. in such cases, the expression in proposition gives us the mean path of price. the review of financial studies / v n we conclude our formal discussion by reexamining the role of the short-horizon assumption in our model. an alternative way of proceeding would have been to assume that consumption takes place only at the very end of the trading period, and that traders are long-lived. in such con- texts, we know from the work of samuelson ( ) that, if traders either have log utility or have constant relative risk aversion and the returns are independent, then traders will act as if they are myopic. the relevant question is how much quantitative significance the assumption of short- lived traders has. simulations in bacchetta and van wincoop ( ) suggest that the difference between the short- and long-lived trader assumption may not be very large quantitatively. for these reasons, as well as for the insights gained, our assumption of short-lived traders would be a useful starting point for a more general analysis. for the two-period version of our model, some formal analysis of the long-horizon case can be provided as a comparison to the short-horizon counterpart. in the long-horizon case, the same traders are present in the market at dates and and maximize the utility of final period consump- tion. this more complex case is again analyzed formally in appendix b. we present here the limiting results as the supply noise becomes large. in the following proposition, esð:Þ denotes the expectation with respect to the noisy supplies. for the limit when the supply becomes very noisy, there is no difference between the expected prices at dates and . proposition . in the two-period model with long-lived traders, as ð� ;� Þ! ð ; Þ, es p ð Þ¼ es p ð Þ¼ � �þ� � � �þ � �þ� � � y the formal limiting argument is in appendix b, but we can present here the simple heuristic argument. period will look identical to the short- lived trader model. so consider the problem of a trader in the first period. he can anticipate what his second-period demand for the asset will be. his first-period demand is not the same as in the short-lived trader model, because of his hedging demand. even if he thought that holding the asset from period to period had a zero or negative expected return, he might want to buy a positive amount of the asset because it hedges the risk that he will be taking on in period . it turns out that in this case, this hedging demand implies that the period trader will purchase his expected demand for the asset in the next period, as a hedge. the net effect of this is that he will behave as if the period trading opportunity does not exist. of course, this makes sense, since p is very noisy in the limit, and much noisier than �. beauty contests and iterated expectations the comparison of the short-run and long-run trader models is instruc- tive. the expected price is biased toward the public signal in the first trading round of the short-run trader model relative to the long-run trader model. short horizons are generating an over-reliance on public information. to be sure, our comparison between short-run and long-run models is somewhat stark. however, it is worth noting that, even in a long-lived asset market, all that is required to get the qualitative features of the short-run model is that some traders consume before all the expected future dividends reflected in the assets they are trading are realized. this is surely a realistic assumption. we could easily introduce hybrid traders who, with probability �, will face liquidity needs and be forced to consume at date and, with probability ��, will not consume until period . the model would move smoothly between the two limits discussed here as we let � vary between and . . discussion our article has a number of antecedents that touch upon the main themes that we have introduced here. a number of articles have examined the role of higher-order beliefs in asset pricing. however, fully rational models are typically somewhat special and hard to link to standard asset pricing models [see, e.g., allen, morris, and postlewaite ( ), morris, shin, and postlewaite ( ), and biais and boessarts ( )]. also, our article is closely related to two recent articles by bacchetta and van wincoop ( , ). the former article presents numerical solutions of asset pricing formulae in the context of foreign exchange markets. the latter article develops the results of our article in the direction of deriving a formula for the ‘‘higher-order wedge’’ in the asset price (i.e., the difference between the asset price and the average expectation of fundamentals). a number of authors have noted that agents will not act on private information if they do not expect that private information to be reflected in asset prices at the time that they sell the asset [e.g., froot, scharfstein, and stein ( )]. this phenomenon is clearly related to the horizons of traders in the market [see, e.g., dow and gorton ( )]. tirole ( ) emphasized the importance of myopic traders in breaking down the back- ward induction argument against asset market bubbles. the behavioral approach exploits this feature to the full by assuming that rational (but impatient) traders forecast the beliefs of irrational traders [e.g., de long, shleifer, summers, and waldmann ( )]. but since irrationality is by no means a necessary ingredient for higher-order beliefs to matter, it seems useful to have a model where rational agents are worried about the forecasts of other rational agents. the existence of an equivalent martingale measure in the standard repre- sentative investor asset pricing model has become a cornerstone of modern the review of financial studies / v n finance since the early contributions, such as harrison and kreps ( ). in some cases, it is possible to extend the martingale property to differential information economies. for instance, duffie and huang ( ) showed that, as long as there is one agent who is more informed than any other, we can find an equivalent martingale measure. in general, however, the exis- tence of an equivalent martingale measure cannot be guaranteed. duffie and kan ( ) give an example of an economy with true asymmetric information (i.e., no agent who is more informed than any other) where there is no equivalent martingale measure. in our case, the average expec- tations operator fails to satisfy the law of iterated expectations. so, if the average expectations operator is also the pricing operator, then we know that there cannot be an equivalent martingale measure. this failure of the martingale property is, of course, hardly surprising. what we want to emphasize is that the martingale property fails for average expectations in a systematic way (e.g., there is a bias toward public information). the arguments that we have presented in this article combine all the above ingredients. the noisy rational expectations model with short-lived traders exhibits the following features: prices reflect average expectations of average expectations of asset returns; prices are overly sensitive to public information; and traders underweight their private information. our assumption of overlapping generation of traders is designed to highlight how closely connected these three features are in a standard asset pricing model. we believe they should be linked in a wide array of asset pricing models. an important issue for future research is the extent to which asset prices in models like the one presented above can be construed as bubbles. chapter of shiller ( ) is devoted to the idea that the news media, by propagating information in a public way, may create or exacerbate asset market bubbles by coordinating market partici- pants’ expectations. news stories without much information content may play a role akin to ‘‘sunspots’’ (i.e., payoff irrelevant signals that coordinate players’ expectations). in our model, if public information suggests that payoffs will be high, then this can lead to high asset prices even if many traders have private information that the true value is low. to the extent that market prices are biased signals of the underlying fundamental liquidation value of the asset, our article may shed light on one important aspect of bubbles in terms of the systematic departure of prices from the common knowledge value of the more precisely, there is no ‘‘universal equivalent martingale measure’’ (i.e., no one probability distribu- tion that could be used to price assets conditional on each trader’s information). in harrison and kreps ( ), the martingale asset pricing formula fails because there are short sales constraints and the asset price depends in each period on the most optimistic expectation in the economy. most optimistic expectations also fail to satisfy a martingale property in a systematic way (they are a submartingale). beauty contests and iterated expectations asset. in our model, public information exercises a disproportionate influence on the price of the asset — pushing it away from the funda- mentals. having said all this, it is also clear that our model fails to capture many aspects of bubbles as they are conventionally under- stood, such as the rapid run-up in prices followed by a precipitous crash. abreu and brunnermeier ( ) have recently modeled such features using the failure of common knowledge of fundamentals. to the extent that failure of common knowledge of fundamentals is the flip side of higher-order uncertainty, abreu and brunnermeier’s work rests on ideas that are closely related to those explored in our article. appendix a proofs of lemmas and . we can verify from the product b*t bt� that �*t� ¼ � * t þ�t� � * tt þ� * t � � �*s;t� ¼ � * s;t þ�s;t� � * tt þ� * t � � , for s � t � �*t� ¼ �t� � * tt þ� * t � � ð Þ this defines a dynamic system whose boundary conditions are given by �*t ¼ �t �*st ¼ �st ; for s � t �*t ¼ �t ð Þ we can see that �*t is a decreasing function of t. this proves lemma . to prove lemma , let us first prove that �*st > �st for s � t < t . the proof is by induction backwards from t . from equations ( ) and ( ), �*s;t� ¼ � * s;t þ�s;t� � * tt þ� * t � � ¼ �s;t þ�s;t� �tt þ�tð Þ ¼ �s;t� þ�tð Þ > �s;t� for the inductive step, suppose �*st > �st. then �*s;t� ¼ � * s;t þ�s;t� � * tt þ� * t � � > �s;t þ�s;t� �tt þ�*t � � ¼ �s;t� þ�*t � � > �s;t� this proves that �*st > �st for s � t < t . from equation ( ) �*t ¼ �t . then, �*t� ¼ � * t þ�t� � * tt þ� * t � � ¼ �t þ�t� �tt þ�tð Þ ¼ �t� þ�tð Þ > �t� for the inductive step, suppose that �*t > �t . then the review of financial studies / v n a*t� ¼ � * t þ�t� � * tt þ� * t � � > �t þ�t� �tt þ�*t � � ¼ �t� þ�*t � � > �t� where the second inequality follows from the fact that �*tt > �tt. this proves lemma . proof of proposition . we begin by demonstrating a result that has some independent interest. we will show that the information value of price pt depends in a simple way on risk tolerance � and the weight given to the private signal xit in forming demands. suppose price takes the form pt ¼ �t e �jy; ; � � � ; t� ð Þþ t�� t st ð Þ the aggregate demand at date t is given by � vart ptþ ð Þ b*t z � pt � � ¼ � vart ptþ ð Þ xt� i¼i �i i þ�t t þ�t�� pt ! setting this equal to supply st , solving for p and comparing coefficients with equation ( ), we have t ¼ �t þ�t and t ¼ �tþ�t��t vartðptþ Þ. thus the random variable pt ��t e �jy; ; � � � ; t� ð Þ ¼ �� t t st has variance � varit ptþ ð Þ ��*t � � which goes to infinity as � ! . in this limit, prices lose all their information value. the precisions f�tg all tend to zero, and the dynamical system above reduces to the pair �*t� ¼ � * t þ�t� � * t �*t ¼ �t� * tþ where �t ¼ �=ð�þ�Þ for any t. thus, �*t ¼ð�=ð�þ�ÞÞ t�tþ . we claim that �*t ¼ � � �þ� � �t�tþ the proof is by induction backwards from t . for t , we have �*t ¼ �t ¼ �=ð�þ�Þ¼ �ð�=ð�þ�ÞÞ. for t, �*t ¼ � * tþ þ � �þ� � �þ� � �t�t ¼ � � �þ� � �t�t þ � �þ� � �þ� � �t�t ¼ � � �þ� � �t�tþ this proves proposition . beauty contests and iterated expectations appendix b in this appendix, we solve our model for the two-period-trading case, first for the short-lived trader model, and then for the long-lived trader model. the short-lived trader model we first solve the short-lived trader model in four steps. we assume that prices follows linear rules and deduce the resulting public and private information in periods one and two (in steps and ). second, by backward induction for what the linear rules must be in the two periods (in steps and ). step : learning from first-period prices. assume that period prices follow a linear rule p ¼ � � y þ �� s ð Þ ð Þ observe that � p �� yð Þ¼ �� s ; ð Þ so � p �� yð Þ is distributed normally with mean � and precision � . thus at period , based on prior information alone, � is distributed normally with mean y ¼ �y þ � � p �� yð Þ �þ � ¼ �� ð Þy þ � � p �þ � and precision � ¼ �þ � : trader i who in addition observes private signal xi will believe that � is normally distributed with mean e i �ð Þ¼ �� ð Þy þ�xi þ � � p �þ� þ � ð Þ and precision �þ� þ � step : learning from second-period prices. now assume that second-period prices follow a linear rule: p ¼ � � y þ �� s ð Þ hence � p �� y ð Þ is distributed normally with mean � and precision � . the review of financial studies / v n trader i who in addition observes private signal xi will believe that � is normally distributed with mean e i �ð Þ¼ � �� þ� þ � � � y þ � � þ� þ � � � xi þ � � � þ� þ � � � p ¼ �þ � �� þ � þ� þ � � � �� ð Þy þ � � p �þ � b@ ca þ � �þ � þ� þ � � � xi þ � � �þ � þ� þ � ! p >>>>>>>>>>>>< >>>>>>>>>>>>: >>>>>>>>>>>>= >>>>>>>>>>>>; ¼ �þ � �� þ � þ� þ � � � �� þ � � � y �þ � �� þ � þ� þ � � � � � �þ � � � p þ � �þ � þ� þ � � � xi þ � � �þ � þ� þ � ! p >>>>>>>>>>>>>>< >>>>>>>>>>>>>>: >>>>>>>>>>>>>>= >>>>>>>>>>>>>>; and precision � þ� þ � ¼ �þ � þ� þ � : step : solving for second-period prices. trader i’s demand for the asset will be � � þ� þ � � � � �� þ� þ � � � y þ � � þ� þ � � � xi þ � � � þ� þ � � � p � p � collecting terms and simplifying, we have � � �� ð Þy þ�xi � � þ� þ � � � � �� p � total demand for the asset will be � � �� ð Þy þ�� þ� þ � � � � �� p � market clearing implies that this equals s (i.e., rearranging), p ¼ � �� ð Þy þ�� s � þ� þ � � � � � so ¼ �� ð Þ � ¼ � � þ�� ¼ �þ � � � � þ�� ð Þ beauty contests and iterated expectations � ¼ � þ �� þ� þ � � � ¼ � þ �� þ � þ� þ � � � ð Þ this is implies that the second-period price is normally distributed with mean �þ � �þ � þ� þ � � � y þ � þ � �� þ � þ� þ � � � � and variance � þ �� þ � þ� þ � � � � � � : define z as z � � þ � �� þ � þ� þ � � � then, p can be written as a linear combination of y, �, and s where p ¼ � zð Þy þ z�� s � � þ� þ � � � � �� ð Þ integrating out the supply shock s , we have that the mean of p is � zð Þy þ z� step : solving for first-period prices. for the short-lived trader, the demand for the asset in period is � e i p ð Þ� p ð Þ var i p ð Þ where e iðp Þ is the i’s conditional expectation of p at date , and var iðp Þ is i’s condi- tional variance of p at date . from equation ( ), trader i’s demand is given by � ze i �ð Þþ � zð Þy � p ð Þ var i p ð Þ ¼ � var i p ð Þ z �� ð Þy þ�xi þ � � p =vari �ð Þ � � þ � zð Þy � p � � where var i �ð Þ¼ �þ� þ � is i’s conditional variance of � based on information at date . the conditional var- iances var iðp Þ and var ið�Þ are identical across traders, and so we can write them simply as var ðp Þ and var ð�Þ. integrating over all traders, the aggregate demand is given by �var �ð Þ var p ð Þ y z �� ð Þþ � zð Þ �þ� þ � � �� þ z�� p �þ� þ � � � � z � � � >>>< >>>: >>>= >>>; the review of financial studies / v n market clearing implies that this is equal to s . rearranging in terms of p and comparing coefficients with equation ( ), we have � ¼ z � þ � �þ� þ � � � � � ¼ � z � þ � �þ� þ � � � � ¼ var p ð Þ �var �ð Þ �þ� þ � � � � z � � h i thus, defining w � � þ � �þ� þ � we can express first-period price as a linear combination of y, �, and s where p ¼ � wzð Þy þ wz�� s var p ð Þ �var �ð Þ �þ� þ � � � � z � � h i integrating out the supply noise s , we have es p ð Þ¼ � wzð Þy þ wz� the long-lived trader model now consider the long-lived trader model. the analysis is unchanged until we derive the first-period prices (step ). now trader’s anticipations of their asset purchases in period two create ‘‘hedging demand.’’ to deduce first-period demand, we need to know trader i’s beliefs about the joint distribution of p and e ið�Þ at date . letting �i ¼ �� e i �ð Þ we have p ¼ � � y þ �� s ð Þ ¼ � � �� ð Þy þ � � p �þ � � � þ �� þ� þ � y þ � �þ� þ � xi þ � � �þ� þ � p þ�i � � � s bbbbbbb@ ccccccca ¼ � � �� þ � � � þ �� þ� þ � � �� y þ� � �þ� þ � � � xiþ � � � � �þ � � � þ � � �þ� þ � � �� p þ� �i �� s >>>>>>>>>>>>< >>>>>>>>>>>>: >>>>>>>>>>>>= >>>>>>>>>>>>; ð Þ beauty contests and iterated expectations so trader i’s expected value of p at date is e i p ð Þ¼ � � �� þ � � � þ �� þ� þ � � �� y þ� � �þ� þ � � � xiþ � � � � �þ � � � þ � � �þ� þ � � �� p >>>>>>>>< >>>>>>>>: >>>>>>>>= >>>>>>>>; : recall from equation ( ) that trader i’s expected value of � at period two will be e i �ð Þ¼ �þ � �� þ � þ� þ � � � �� þ � � � y �þ � �� þ � þ� þ � � � � � �þ � � � p þ � �þ � þ� þ � � � xi þ � � �þ � þ� þ � � � p >>>>>>>>>>>>>< >>>>>>>>>>>>>: >>>>>>>>>>>>>= >>>>>>>>>>>>>; : the expected value of the expected value of � at period is e i e i �ð Þð Þ¼ �þ � �� þ � þ� þ � � � �� þ � � � y �þ � �� þ � þ� þ � � � � � �þ � � � p þ � �þ � þ� þ � � � xi þ � � �þ � þ� þ � � � � � �� þ � � � þ �� þ� þ � � �� y þ� � �þ� þ � � � xiþ � � � � �þ � � � þ � � �þ� þ � � �� p >>>>>>>>>>< >>>>>>>>>>: >>>>>>>>>>= >>>>>>>>>>; >>>>>>>>>>>>>>>>>>>>>>>>>>>< >>>>>>>>>>>>>>>>>>>>>>>>>>>: >>>>>>>>>>>>>>>>>>>>>>>>>>>= >>>>>>>>>>>>>>>>>>>>>>>>>>>; : this equals: �þ � �� þ � þ� þ � �� þ � þ � � �þ � þ� þ � � � � � �� þ � þ �� þ� þ � � �� y þ �þ � �� þ � þ� þ � � � �þ � � �þ � � �þ � þ� þ � � � � � � � �þ � þ � � �þ� þ � � �" # p þ � �þ � þ� þ � þ � � �þ � þ� þ � � � � � �þ� þ � � �� xi >>>>>>>>>>< >>>>>>>>>>: >>>>>>>>>>= >>>>>>>>>>; now e iðp Þ� p equals the review of financial studies / v n � � �� þ � � � þ �� þ� þ � � �� y þ� � �þ� þ � � � xiþ � � � � �þ � � � þ � � �þ� þ � � �� p >>>>>>>>>< >>>>>>>>>: >>>>>>>>>= >>>>>>>>>; � p ¼ � � �� þ � � � þ �� þ� þ � � �� y þ� � �þ� þ � � � xiþ � �� þ � � � þ � � �þ� þ � � �� p >>>>>>>>>< >>>>>>>>>: >>>>>>>>>= >>>>>>>>>; ð Þ and e iðe ið�ÞÞ� e iðp Þ equals �þ � �� þ � þ� þ � �� þ � þ � � �þ � þ� þ � � � � � �� þ � þ �� þ� þ � � �� y þ �þ � �� þ � þ� þ � � � � � �þ � � �þ � � �þ � þ� þ � � � � � � � �þ � þ � � �þ� þ � � �" # p þ � �þ � þ� þ � � � þ � � �þ � þ� þ � � � � � �þ� þ � � �� xi >>>>>>>>>>>< >>>>>>>>>>>: � � � �� þ � � � þ �� þ� þ � � �� y þ� � �þ� þ � � � xiþ � � � � �þ � � � þ � � �þ� þ � � �� p >>>>>>>>>>< >>>>>>>>>>: >>>>>>>>>>= >>>>>>>>>>; ¼ �þ � �� þ � þ� þ � � � �� þ � � � þ � � �þ � þ� þ � � � � � � � � �� þ � � � þ �� þ� þ � � �� y þ �þ � �� þ � þ� þ � � � � � �þ � � � þ � � �þ � þ� þ � � � � � � � � � � �þ � � � þ � � �þ� þ � � �� p þ � �þ � þ� þ � � � þ � � �þ � þ� þ � � � � � � � � �þ� þ � � � xi >>>>>>>>>>>>>>>>>>>>>>>>>>>>< >>>>>>>>>>>>>>>>>>>>>>>>>>>>: >>>>>>>>>>>>>>>>>>>>>>>>>>>>= >>>>>>>>>>>>>>>>>>>>>>>>>>>>; now the variance of � at period will be ¼ �þ � þ� þ � the variance of p for a trader in period is � ¼ � �þ� þ � þ � � : beauty contests and iterated expectations at period , e ið�Þ is perfectly correlated with p . the variance of e ið�Þ is equal to times the variance of p , where ¼ � � �þ � þ� þ � using the formula in brown and jennings ( ) [see also brunnermeier ( ), page ], trader i’s demand for the asset will be � � þ � ð Þ ! e i p ð Þ� p ð Þþ � � � e i e i �ð Þð Þ� e i p ð Þð Þ " # now observe that, as � ! and � ! , we have ! �þ� ; � ! � � and ! � � �þ�. so � þð � Þ ! �þ� and � ! �þ�. also observe from equations ( ) and ( ) that, as � ! and � ! , e i p ð Þ� p ! � � �þ� � � ! y þ � �þ� � � xi ! � p e i e i �ð Þð Þ� e i p ð Þ! � �þ� � � y þ � �þ� � � xi � � � � � �þ� � � ! y þ � �þ� � � xi ! thus total demand for the asset is � �þ�ð Þ � �þ� � � y þ � �þ� � � �� p � � : this is the same as in period two, so we get the same distribution of p . references abreu, d., and m. brunnermeier, , ‘‘bubbles and crashes,’’ econometrica, , – . admati, a. r., , ‘‘a noisy rational expectations equilibrium for 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studies, , – . woodford, m., , ‘‘imperfect common knowledge and the effects of monetary policy,’’ in p. aghion, r.frydman, j. stiglitz and m. woodford (eds.), knowledge, information and expectations in modern macroeconomics: in honor of edmund s. phelps, princeton university press. the review of financial studies / v n pii: s - ( ) - previews the crystal structure of sura is the foundation stone to understanding sura functions at a molecular level. the urgent questions of how sura recognizes, binds, and releases its outer membrane protein substrates and how it facilitates their maturation without the driving force of atp hydrolysis can now be directly addressed. new, exciting insights are likely to emerge within the near future. moreover, the structure paves the way to face the next big challenge—studying the protein dy- namics involved in substrate binding and release. susanne behrens department of molecular genetics and preparative molecular biologyviews of the putative polypeptide binding channel in sura institute for microbiology and geneticssurface rendering of sura, highlighting the channel and putative georg-august university göttingenpolypeptide binding surface (green) and the proline binding pockets of the inactive (blue) and active (orange) ppiase domains (kindly grisebachstrasse provided by e. bitto and d. mckay). the left sura molecular is shown d- goettingen in the same orientation as the first figure. germany selected reading tide binding channel finds further support in crystal- . hartl, u.f., and hayer-hartl, m. ( ). science , – .packing interactions. in the crystallographic unit, a short . sauer, f.g., knight, s.s., waksman, g.j., and hultgren, s.j. helical peptide segment that sits piggyback on sura ( ). semin. cell dev. biol. , – . binds to the flap-like structure of the adjacent sura . spiess, c., beil, a., and ehrmann, m. ( ). cell , – . molecule. however, there are at least two caveats with . krojer, t., garrido-franco, m., huber, r., ehrmann, m., and clausen, t. ( ). nature , – .this interaction identifying the substrate binding pocket. . rouvière, p.e., and gross, c.a. ( ). genes dev. , –first, it spans only a fraction of the actual capacity of .the crevice. more importantly, the bound peptide has . missiakas, d., betton, j.m., and raina, s. ( ). mol. microbiol. �-helical conformation whereas the known sura sub- , – . strates, the outer membrane porins, are � stranded. is . behrens, s., maier, r., de cock, h., schmid, f.x., and gross, c.a. ( ). embo j. , – .the channel indeed the polypeptide binding site relevant . bitto, e., and mckay, d. ( ). structure , this issue, –to the chaperone function in sura, and if so, which parts .of it actually form the binding surface? is the observed . lu, k.p., hanes, s.d., and hunter, t. ( ). nature , binding specificity of sura [ ] determined by primary – . polypeptide sequence, secondary structure, or possibly . dolinski, k., muir, s., cardenas, m., and heitman, j. ( ). proc. natl. acad. sci. usa , – .both? proteins and the corresponding receptors) and cotrans- lational transport of proteins into the endoplasmic retic- structure, vol. , november, ,  elsevier science ltd. all rights reserved. pii s - ( ) - obg, a g domain with a beautiful extension ulum (er). the remaining gnbps form a large group of different proteins [ ]. the common property shared by these is that they contain a more or less conserved structural module, the g domain, which is usually in- the structure of obg, a protein involved in a compli- volved in the switching of the protein between a gdp- cated genetic network that regulates stress response bound and a gtp-bound conformation [ – ]. with the and sporulation in bacillus subtilis, reveals a com- exception of translation factors, the signal recognition pletely new type of guanine nucleotide binding protein particle and its receptor, most of the guanine nucleotide and provides some hints about its function. binding proteins mentioned above are found only in eu- karyotes. recently, in large part fuelled by the large guanine nucleotide binding proteins (gnbps) regulate sequencing projects going on worldwide, it has become many different types of processes in both prokaryotes clear that there are a number of guanine nucleotide binding and eukaryotes. they come in a large variety of different proteins that are conserved from bacteria to man and that sequences and shapes. the most important and widely the functions of most of these are unknown [ ]. studied groups are the family of protein biosynthesis one of these is the protein obg, which was first dis- factors acting on the ribosome, the heterotrimeric g covered in the bacillus subtilis spo operon as a protein proteins, the ras superfamily of small – kda pro- involved in a complicated genetic network that regulates stress response and sporulation. hence the name, obg,teins, and the factors involved in signal recognition (sr structure which derives from spo b-associated gtp binding pro- some hints about the function of obg come from some lucky accidents. although the protein was purifiedtein. the exact function of this protein is not known, and many proposals have been put forward for its biological without the addition of nucleotides, one of the mono- mers in the dimeric asymmetric unit contained, in addi-function. to approach the functional role from a struc- tural perspective, the group of chris lima, in the course tion to the � phosphates sitting in the p loop, additional density bound to ribose, which was modeled as ppg-of a structural genomics project, has now solved the structure of the bacillus subtilis obg, which appears in �pp, a nucleotide that is part of a stress response and accumulates to millimolar concentrations in the cell. in-this issue of structure [ ]. unlike the g domain-only proteins of the ras super- cidentally, the tgs domain, which was absent in the present structure, is found in a number of proteinsfamily, obg is a large protein that consists of three do- mains, an n-terminal glycine-rich domain, a ras-like g known to interact with ppgpp. while this seemed to suggest a contribution of the tgs domain, the biochemi-domain, and a c-terminal tgs domain. the latter is a small domain found in a number of proteins that have the cal experiments did not reveal such a contribution. al- though it is not completely clear whether the presence ofcommon property of being involved in bacterial stress response. unlike ras or g� proteins, obg, like a number ppgpp is functionally relevant, biochemical experiments showed that ppgpp is having some effect on the rateof other gnbps, shows micromolar affinity for gdp/ gtp, which results in fast exchange of the nucleotide of gtp hydrolysis. however no direct binding of the nucleotide was observed, and the effects on the gtpaseand thus does not require a guanine nucleotide ex- change protein (gef), which, in ras and g�, regulates were somewhat inconsistent. in any case the fact that ppgpp, and not any other guanine nucleotide, was foundactivation. it has a very slow gtpase, with a rate on the same order as that of the ras proteins (� . min� ), in the protein and was retained during the purification procedure warrants further experiments to test the im-suggesting that there may be a gtpase-activating pro- tein (gap) or another mechanism that increases the rate portance of this observation for the role of obg in stress response. nothing at all is known about the role of mam-of the reaction [ ]. however, like guanine nucleotide binding proteins such as hgbp, dynamin, and septins, malian obg proteins. since ppgpp is not involved in it does not have a glutamine residue in the switch ii eukaryotic stress response, we still have to look ahead region, which has been shown to be crucial for the for some more biology on this seemingly important gtp gtpase reaction of ras and g� proteins, suggesting a binding proteins. rather different mechanism of gtp hydrolysis. obg is a completely new type of guanine nucleotide the structure of obg shows the well-known features binding protein. it is just another example of how a of the g domain, which typically contains six � strands conserved module, the g domain, has been used for and five � helices. obg has one additional � strand in many different switching reactions. as with other gua- the switch i region and one additional � helix in the nine nucleotide binding proteins, the structures of the switch ii region. the putative switch regions are involved nucleotide-free and the ppgpp-bound forms are only in the interaction with the rest of the structure, such that the beginning. more structures are needed to fully un- one could envision nucleotide-dependent changes in derstand the switching mechanism and what biological the interface between the g domain and the rest of the processes it drives, but the present structure is a marvel- molecule. while the structure was solved in the presence ous beginning. of various nucleotides, no significant structural changes were observed, although this could be due to con- alfred wittinghoferstraints of the crystal packing. max-planck-institut f. molekulare physiologiethe most remarkable feature of the structure is the dortmundn-terminal part of the obg, which is unique and is thus germanycalled the obg fold. it is an elongated barrel, the lower part of which consists of an eight-membered � sheet selected reading sitting on top of, and interfacing with, the g domain. the glycine-rich part of the obg fold consists of a six- . leipe, d.d., wolf, y.i., koonin, e.v., and aravind, l. ( ). j. helix bundle, where the helices share structural features mol. biol. , – . . kjeldgaard, m., nyborg, j., and clark, b.f. ( ). faseb j. ,with a type ii polyproline helix. the six helices pack – .together in parallel and antiparallel pairs. there is an . sprang, s.r. ( ). annu. rev. biochem. , – .extensive main chain hydrogen bonding pattern be- . vetter, i.r., and wittinghofer, a. ( ). science , – . tween the helices. probably for steric reasons, most of . buglino, j., shen, v., hakimian, p., and lima, c.d. ( ). struc- the invariant glycines are in the interior of the fold, which ture , this issue, – lacks a normal hydrophobic core and is instead stabi- . prakash, b., renault, l., praefcke, g.j.k., herrmann, c., and wittinghofer, a. ( ). embo j. , – .lized by side chain interaction on the outside of the fold. . .j.ajce. . american journal of civil engineering ; ( ): - http://www.sciencepublishinggroup.com/j/ajce doi: . /j.ajce. . issn: - (print); issn: - (online) philosophy and perception of beauty in architecture reham alasmar department of architecture, faculty of engineering, the university of jordan, amman, jordan email address: to cite this article: reham alasmar. philosophy and perception of beauty in architecture. american journal of civil engineering. special issue: aesthetics and perception of beauty in architecture. vol. , no. , , pp. - . doi: . /j.ajce. . received: october , ; accepted: november , ; published: november , abstract: definitions of beauty and space are as diverse as defined by the disciplines in which it plays a fundamental role; from science and philosophy to art and architecture, each field’s definition for the perception of the beauty of space is often simplified or reduced. this consequently denies us access new spaces whose definitions and perspectives, strategies and impacts on human perception of beauty of space are rarely considered in any cohesive manner. the debate, “perception of beauty in architecture and human perception of space”. the research tries to reflect upon new understanding to the meaning of beauty in architecture and thus access new definitions and understanding to the beauty perspectives, strategies and processes of perception beauty in architecture. some works of architecture have remarkable aesthetic value. according to certain philosophers, part of this value derives from the appearance of such constructions to fulfill the function for which they were built. the research digs through the dilemma of form follows function and argues that one way of understanding the connection between function and aesthetic value resides in the concept of functional and beauty together not the idea of function vs. beauty; the paper attempts to offer a better way of understanding it. keywords: aesthetics, perception, beauty, illusion . introduction architecture influences the community through combining human activity with adapted site context, organized programmatic and interstitial space, and exploration of material. the dynamics of human perception, of the individual as a person and the community as a society, should influence design form and function, in terms of circulation and organization to produce sensory architecture. architecture is designed to attend to the needs of human activity and creates a relationship between human sensation and the building envelope to transform perception. throughout history there are a correlation between the human body and architecture, specifically in its relationship to human perception. “the environment influences human beings, and this implies that the purpose of architecture transcends the definition given by early functionalism” [ ]. . perception . . ecological nature of perception the perception is the process by which an individual select, organizes and interprets stimuli into a meaningful and articulate image of the environment in which he lives. the humans perceive surrounding through a process: figure . process of perception. . . . influential factors of perceptual selectivity the factors influencing perception of human varies between an external attention factors and internal set factors; where intensity, size, contrast, repetition and motion are an external attention factors, and learning and perception, personality and perception, and motivation and perception are an internal set factor. also, the perception can be influenced by the perceiver himself, the situation and the target. american journal of civil engineering ; ( ): - . . . principles of perceptual organization a) proximity rule in mentally organizing stimuli, objects that are physically close to one another are grouped together or perceived as a unit. [ ]. figure . proximity rule. b) similarity rule in organizing stimuli, elements that appear similar in color, lightness, texture, shape, or any other quality are grouped together. [ ]. figure . similarity rule. c) continuity rule the law of continuity leads us to see a line as continuing in a direction, rather than making an abrupt turn. we tend to favor smooth or continuous paths when interpreting a series of points or lines. [ ]. figure . continuity rule. d) closure rule in organizing stimuli, the fill in any missing part or incomplete figures and see them as complete figures. [ ]. figure . closure. e) principle of symmetry organizing stimulus, we tend to favor symmetrical objects or relationships. figure . principle of symmetry. f) figure-ground rule perception does not only involve organization and grouping, it also involves distinguishing an object from its surroundings. once an object is perceived, the area around that object becomes the background. [ ]. figure . figure ground rule. . . perception versus sensation sensation is the process of detecting, receiving, converting and transmitting information resulting from stimulation of sensory receptors. while the perception is defined as the process of selecting, identifying, organizing and interpreting sensory input into a useful and meaningful mental reham alasmar: philosophy and perception of beauty in architecture representation of the world in the light of relevant memories from past experiences. [ ] the basic function of sensation is recognition of sensory stimuli, whereas perception commonly involves interpretation and justification of the same stimuli. our senses tell us something is out there, while our perception tells us what that something is. our sense matters translation of physical energy from the surrounding environment into electrical impulses to be processed by the brain. but the signals aren’t understood as pure energy. the process of perception allows us to interpret these signals as objects, events, people, and situations. without the ability to organize and interpret sensations, life would seem like a meaningless jumble of colors, shapes, and sounds. synesthesia literally means “mixing of senses,” people with synesthesia routinely blend their sensory experience. . . theories of perception – gestalt theory gestalt school practiced a series of theoretical and methodological principles that attempted to redefine the approach to principles to psychological research. in contemporary philosophy the concept of gestalt was first introduced by christian von ehrenfels (a member of the school of brentano). there are major theoretical principles of gestalt psychology; principle of totality: the experience of perception must be considered globally through taking into account all the physical and mental aspects of the individual simultaneously because the nature of the mind demands that each element must be considered as part of a system of dynamic associations. principle of psychophysical isomorphism is a connection exists between conscious experience encephalic activity. the principles of gestalt systems: a) emergence: this is a description of what occurs in vision and not an explanation of what occurs. gestalt theory does not explain how the percept of a thing emerges. b) reification: the generative aspect of perception, by which the experienced percept contains more explicit spatial information than the sensory stimulus on which it is on which it is based. c) multistability: (multistable perception) is the tendency of ambiguous perceptual experiences to pop back and of ambiguous perceptual forth unstably between two or more alternative interpretations. d) invariance: is the property of perception whereby invariance simple geometrical objects are recognized independent of rotation, translation, and scale; as well as several other variations such as elastic deformations, different lighting, and different component features. . space perception "space perception is a process through which humans and other organisms become aware of the relative positions of their own bodies and objects around them. space perception provides cues, such as depth and distance, which are important for movement and orientation to the environment." [ ]. centuries of experimental research led to a more tenable conception in which space was described in terms of three dimensions or planes: a) height (vertical plane). b) width (horizontal plane). c) depth (sagittal plane). these planes all intersect at right angles, and their single axis of intersection is defined as being located within perceived three-dimensional space—that is, in the “eye” of the perceiving individual. our perception of space is strictly linked to spatial factors, such as composition, orientation and complexity. furthermore light, reflection, materiality and sound play an important role for our sense of space. [ ]. our three-dimensional impression is the result of the evaluation and interpretation of the mentioned properties. perception of place is important. it embeds within occupant memory and influences an occupant’s learned history or experience of that place. because of perception architectural nodes and approaches are often celebrated. for example, a massive exterior can add an element of astonishment for that delicately floated interior space. . . the visual nature of space experiencing space is a subtle act of the human body and mind. we use our eyes to visually probe a space, making thousands of subconscious computations every second. way finding, orientation, direction, etc. the lens of our eye, with a mm focal length allows us to experience perspective space in a consistent and readable way. [ ]. space is self-evident, but the way we perceive it is not. our brain has built in mechanism that allows visual inputs to be recorded and processed, outputting information almost simultaneously that we then act upon. the processing of visual information sometimes triggers cognitive loopholes. these loopholes are known as optical illusions. illusions trick our brain’s visual mechanics and have limiting relevance on three dimensional spatial effects. . . spatial vs. visual our experience of space is largely determined by our biopsychology. in research from edvard and may-britt moser won the nobel prize for physiology and medicine. a series of geometric grid-like cells inside the brain of rat are discovered, these cells function much like a gps system, allowing us to spatially map and navigate space in an objective way. our movement through space is recorded by american journal of civil engineering ; ( ): - our brain using acceleration, movement and speed. this means that for each spatial situation, there is an objective recording and reading occurring within our brains. [ ]. supplementing the spatial recording in the entorhinal cortex is a recording of visual properties in the hippocampus. this deal with recording colors, textures and recalling memories that have occurred in visually similar spaces. a complex series of information exchange occurs between these two distinct portions of our brain, allowing us to write, recall and place memories. this duality help explains why memory is so closely tied to place. if every person can write spatial memories or draw it as diagrams, then it is not our language or culture that commands how we react to a space, but rather a combination of objective human nature and hyper- individualistic responses. the spatiality of various architectural typologies is powerful in the way that they are able to affect the biopsychology of an individual in a moment and time of life. . . spatial types symmetrical spaces create the effect of monumentality. asymmetrical spaces are less monumental by their very nature, as they allow for more variation and dynamisms and do not have such a rigid hierarchy. the spatial effects of scale differ as to whether it is the absolute scale of an object or space or relative to that of another. absolute scale is best used when the user can experience a large object and slowly approach it, fully understanding its massiveness. entering narrow passageways before being led into a spread-out void is a compelling spatial effect. the spatial effect of bearing is especially effective because it is a common to all cultures and all architectural movements worldwide. the more reduced this structural relationship is, the more elementary it becomes. porosity is the measure of voids within a solid of composition. it exists purely in three dimensions and is spatially significant because it creates spaces that are varied and interconnected. it blurs the firm boundaries between space and architectural elements. porous objects are varied in their scale and composition, characteristics that put the user in the forefront of the space or object. there are numerous spatial effects that have been used compelling throughout the history of architecture. it is our role as architects to evaluate each project considering site; client and function and to decide which types of spaces we want to create. the vessels that architects are designing contain space, and that powerful spaces have a primacy that goes far beyond that of provocative shapes. architecture is one of the only professions that create space and it should embrace the opportunity to better understand the spatial qualities we are designing. . beauty there is no particular definition of beauty; it is defined as a basic pleasure. and can be something intrinsic to object (color, form, and other qualities) or simply the pleasure an object evokes. . . aesthetics the term aesthetics is derived from the greek word aisthanesthai which refers to perceive cognition. means the things that are recognizable. aesthetic experience as a particular case of integration with aesthetic theme for no other reason than to continue interacting with it as a result of what we feel of pleasure, discovery, satisfaction or concern with the impact of this interaction. distance is the hallmark of the most important steps during artistic creation and it can be useful in describing what is generally called artistic mood. the th century's leading physicists agree that beauty is the primary yardstick of practical truth. the aesthetic preference is a complex process that includes comparisons, distinctions and choices between available aesthetic alternatives. this aesthetic preference is expressed through special aesthetic judgments issued by the individual. . . theories of beauty in architecture . . . golden ratio ratio of the sum of the quantities to the larger quantity is equal to the ratio of the larger quantity to the smaller one. ancient greek mathematicians first studied it because of its frequent appearance in geometry. the ratio is approximately . . “extreme and mean ratio" was the principal term used from the rd century bc until about the th century. [ ]. figure . golden ratio in architecture. reham alasmar: philosophy and perception of beauty in architecture . . . vitruvius's theories of beauty vitruvius believed that an architect should focus on three central themes when preparing a design for a building: firmitas (strength), utilitas (functionality), and venustas (beauty). [ ]. venustas theory is a complicated one. vitruvius thought that a timeless concept of beauty could be learnt from the 'truth of nature', that nature's designs were based on universal laws of proportion and symmetry. he thought that the body's proportions could be used as a model of natural proportional perfection. vitruvius showed that the 'ideal' human body formfitting exactly into a square and a circle, and thus illustrated the link that existed between perfect geometric forms and the perfect body as he believed. it followed, an architect's designs must refer to the unquestionable precision of the body's symmetry and proportions. . perception of beauty the question of whether architecture matters or not is something that you see running right through the history of religion, politics, economics, art and so much more. there is a very basic thought of whether the space that we are in creates an influence, either negative or positive, that we should take very seriously, and if so, we should respond to that challenge. the problem with unsuccessful architects is that what they do hangs around for a very long time. in other words, architecture is a serious business, and i do think that it impacts on our state of mind. so, if you become sensitized to architecture and its good and bad moments, you will be unhappy a lot of the time, because most of the world has gone wrong. architects who worked aesthetically in architecture become what the th century started to get to know as an 'aesthete'. the most famous aesthete in the th century was of course oscar wilde, who famously said that “the wrong kind of wallpaper could upset him far worse than a death in the family”. [ ]. a beautiful building was understood to be a classical building. it is one that basically borrows from the architecture of the greeks and the romans. so, whereas in , the choice of beautiful building has been classicism. when sensitive architectural critics saw these buildings, they were disgusted, and it seemed to them an indicator of everything that could start to go wrong when choice entered the field of architecture, when people could not distinguish if something is beautiful or not. now, the answer, when it eventually starts to emerge, starts to come from an odd direction - not from architects, but from engineers. you look at what a building should do, and that determines what it should look like. so, there should be no more arguments about aesthetics, no more agonized discussions about what sort of arch to put in. you would look at what the programme is, you would look at what the function is, and you determine what a building should look like in that way. this is a very unusual assumption. for thousands of years, architects had seen their job as of course having certain functional, mechanical directions - keeping out the rain, etc. - but they also saw themselves as decorators and as artists. modernist architects rejected all of this, where the french architect le corbusier, who came at the beginning of the th century and work against decoration and aesthetic motivations of traditional architects. le corbusier talked about efficiency, but he was just interested in things looking nice, and if it was a choice of it really working or looking like it worked, he always wanted things to look like they worked. the language of science is used by the modern movement in architecture to justify its choices. [ ]. building performance is used by architects traditionally to ground their decisions in arguments. where in recent years we are seeing that architects are beginning to discover that the reason of doing things in such way is its nice image. we are slowly seeing a return in architecture of an awareness that buildings should be communicating and that a good building is not just an efficient building, it is also one that talks to us of the right sort of things. now, the interesting thing is that when we say that we find something beautiful, we are not just saying that we like the way it looks. if you scratch below the surface, really what we are saying is we like the outlook on life that this object is suggesting to us. so, if you think this building is beautiful, one way of describing that beauty is to describe simply the physical object, but another way of doing it is to say, for instance, that there is some sort of harmonious feeling that is coming from it, and that you want to live there, and you could quite easily describe the qualities of the life that you might have if you lived around it. “if we have settled that aspect of things, we are still left with all sorts of conundrums, one of which is that, if we accept that beauty is important, and if we accept that beauty emanates from the personality of objects.” [ ]. so, it is almost as though, when decorating spaces, what we try to do is to surround ourselves by objects which capture a spirit, as i say, that we're attracted to but don't fully possess. there is something elusive about the things that we find beautiful. deconstructivism is a movement of the middle to late twentieth century that focused on the importance of language. essentially, the deconstructivism believed that an individual's perception was predetermined by their thoughts, knowledge, and cultural background. this movement became the base for postmodern architecture, and it adopted that language and symbolism were essential building blocks of architecture. [ ]. american journal of civil engineering ; ( ): - the contemporary view, which taken by philosophers and psychologists in the past two decades, is that perception and language are different things, and perception does not occur immediately. rather, through the process of perception people first perceive, then think, and thirdly conceptualize or express thoughts. the architectural postmodernism used symbolism to give meaning to their architectural concepts. its language-based architecture was a series of symbolic objects as intellectual exercise in building. the problem is that the architecture offered little in terms of objective spatial qualities. the contemporary view allows for the design and experience of space without symbolism and without needing a metaphor, the primacy of space becomes much more important. this creates a sense where architects do not need to reference something outside of architecture. architecture after that can be made up of simple, proto architectural elements and objects. . illusion and perception in architecture impressions of space and structure can be controlled to create illusions of symmetry, scale, distance, ‘weightlessness’, and even ‘dematerialization’ of the visual planes by altering ‘proportions and appearance’. ruskin notes that “all architecture proposes an effect on the human mind, not merely a service to the human frame” [ ]. . . illusion of scale the illusion of scale was a technique utilized in the library of celsus, in the roman city (asia minor). in a limited area amid existing buildings, the building appears to be enormous. the twenty-one meters wide marble-paved courtyard leads to the two-story gallery, which rests at the top of nine wide marble steps. pairs of columns support pediments located on two levels; the central columns create the illusion of enlarged space between the columns. along with the inclined edges of the podiums, the size of the central doorway strengthens the illusion by being perceived taller and wider than other adjacent. figure . library of celsus. . . illusion of weightlessness architectural objects can look suspended in space in spite of their massive structure. in istanbul, turkey, the church of hagia sophia, built by isadora’s and anthemion, circa , is a byzantine church, later used as an ottoman mosque, and is currently serving as a museum. its massive dome appears light on the lower structure above the huge volume, though hidden structural piers to provide required support. [ ]. figure . hagia sophia. gothic churches present a similar effect, where monumental ‘external “flying buttresses”’ were used to sustain the weight of the roof, while being hidden from viewers inside, and producing the effect of lightness. the coutances cathedral is considered a classic example. figure . the cathedral at coutances. . . illusion of plane dematerialization mediterranean and eastern cultures have exhibited ‘patterned optical illusions’ on floors of tiles or woodwork, which seem to deconstruct the flat plane of floor and design another illusive one. examples have been found in a number of countries including andalusia, morocco, japan, china, india, persia, and italy. [ ]. reham alasmar: philosophy and perception of beauty in architecture figure . mosaic tile patterned floor at alcazar, seville (spain). . . correctional illusion the satisfaction of eye occurs only when the appearance is satisfactory. there have been instances through history where the mistakes of pure vision have been overcome by correctional design techniques. [ ]. since what is true appears false and things seem different from what they are, in representing them we must add or subtract. while if it is an architectural facade, this involves deconstruct lines or replace it by curves, thickening and disposing selective parts. figure illustrates columns that swell in the middle, corner columns swell, and architraves lean forward. figure . irradiation in architecture. optical illusion can play a subtle role in everyday living – even affecting how architecture is constructed. parthenon’s outer columns looks thicker at the top and rectilinear inward at a slant so that from certain viewpoints the building appears taller and straighter. optical illusion that can change your perception: a huge impact on the size, proportion and mood of a space. acknowledgements i submit my heartiest gratitude to my parents for their keen interest, encouragement and great help through working on this research paper. references [ ] theory of phenomenology: analyzing substance, application, and influence. ( ). arch : theory and context. [ ] perception, s. a. ( , ). introductory psychology. retrieved from lumenlearning: https://courses.lumenlearning.com/suny-hccc-ss- - /chapter/gestalt-principles-of-perception/ [ ] west, p. y. ( ). space perception. encyclopaedia britannica. [ ] coyle, a. ( ). managing prisons in a time of change. london: international centre for prison studies. [ ] cladera, a. ( ). the ultimate photography guide to depth of field (dof). photopills. [ ] hodges, f. m. ( ). the promised planet: alliances and struggles of the gerontocracy in american television science fiction of the s. [ ] akhtaruzzaman, m., & shafie, a. a. ( ). geometrical substantiation of phi, the golden ratio and the baroque of nature, architecture, design and engineering. international journal of arts. [ ] kruft, h. ( ). a history of architectural theory from vitruvius to the present. london. [ ] botton, a. d. ( ). the architecture of happiness. new york: vintage books. [ ] ozkan, s. ( ). development of thinking and theory in architecture. csbe. [ ] tmd studio, ( ). the visual nature of space, spatial perception and architecture. [ ] l, a. d. ( ). delight, the function of ornament, an exploration of its relevance. the netherlands. [ ] allen, w. ( ). hagia sophia, istanbul. arts and humanities. [ ] devine, p, g., & sherman. ( ). intuitive versus rational judgment and the role of stereotyping in the human condition; kirk or spock, psychological inquiry. [ ] anthony j. reilly. ( ). three approaches to organizational learning. jsmith library body. wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ june ecological restoration : • ecological restoration vol. , no. , issn - e-issn - © by the board of regents of the university of wisconsin system. editorial ecological beauty, in the eye of the beholder steven n. handel no one loves a thistle. okay, okay, a goldfinch, foraging for lipid-rich seeds does, but not your neighbor, not your local park superintendent, not your golf course manager. we learned this once after installing a small coastal wild- flower meadow including some thistles embedded in a residential zone. the next-door neighbor, phil, told us, “i hate it.” we reposted, “but look, it’s like a monet painting, full of colors, textures, and interesting stems even during the winter. butterflies visit the meadow; look!” “i hate it,” he repeated, “it’s full of thorns. i can’t play catch or frisbee with my son there. it’s got bugs. i hate it.” so human ecology perceptions of usefulness intruded on our cloistered world of botanists. and it came to stay. so many practitioners of restoration ecology are drawn to this field by their cultural affections, the beauty and solace of a walk in the woods or fields. however, in a world of tight budgets, burgeoning human populations demand- ing space, and commercial interests always looking for a location to make a buck (or a yuan), the many values of our restored landscapes need to be communicated more forcefully. our understanding of the true value of healthy habitats is now collectively branded as ecological services. a series of professional reports is now available to us, providing a better understanding of the comprehensive values of restored landscapes (see references, below). ecological services include production of materials for our communi- ties, including food items, medicinals, wood for construc- tion and fuel, oil, and freshwater (stored and cleansed by healthy habitats). ecoservices include regulating the quality of air and soil. restored habitats also bind the soil, lowering erosion of fertile lands. they mediate the negative effects of flooding and disease outbreaks. for example, in our urban areas trees lower the ambient temperature and raise humidity. particulates and other pollutants can be removed from the air column by habitat stands. all plant growth involves removing carbon dioxide from the air and sequestering it in long-maintained carbon stores. wetland habitats help control the disastrous effects of flooding and absorb energy from major storms. habitats support a huge number of microorganisms whose physiological abilities break down many pollutants and can control pathogens. habitat par- cels also support pollinators necessary for so many of our crops (buchmann and nabhan ). any restored habitat also has supporting services for the many animal species that themselves help control insect pests and cycle critical nutrients. any addition of restored lands represents a new stock of genetic diversity to increase resilience of landscapes in a world of changing climate. restored lands have many cultural services in addition to the aesthetic values which are most often cited. there is an increasing literature on the value of restoration for mental as well as physical health, a vital need of our communities. many religions rely on natural areas for rituals and cel- ebrations, but all people seem attracted to outdoor spaces for a greater sense of their place in the world. together, these point to the great spiritual values of restored lands. finally, and not to be minimized, an enormous percent- age of today’s world’s tourism is to ecological destinations. restored habitats consequently raise the economic status of many communities, an advantage that can be translated into many other civic improvements for local people. in , the economics of ecosystems and biodiversity (teeb) estimated global earnings of almost us$ trillion from ecotourism. restoration of land may properly be categorized as an investment, not a loss of funds. political and public support is needed for restoration progress. governmental traction for restoration in new orleans, la took hold when the value of marshes in con- trolling storm surges was explained. in new york city, ny, restoration of woodlands was shown to reduce asthma in the city’s children. restoration of meadows, pollinator nesting areas, in rural areas can increase crop yield in agri- cultural fields. conservation and restoration of old pine forests in the carolinas help persistence of the red-cockaded woodpecker, a rare species of regulatory concern. the editorial by kris decleer in this issue details wide-ranging • june ecological restoration : actions by the european community, recognizing these many ecoservices of restoration. these advantages trump present aesthetics and solely recreational value for many restoration initiatives. in the beauty contest of public opinion, each age chooses the values it deems most alluring, whether that is a habitat’s ability to save energy, moderate climate, to support a rare or iconic species, or to recharge a troubled water table. by restoring a diverse and functioning community, we secure so many services by having a foundation of countless spe- cies interactions. a restored site can be, like cleopatra, accepted as a beauty regardless of the current standard used for judgment. age cannot wither her, nor custom stale her infinite variety. (shakespeare, anthony and cleopatra, act ii, scene ii) references buchmann, s.l. and g.p. nabhan. . the forgotten pollinators. washington dc: island press. daily, g. c. (ed). . nature’s services: societal dependence on natural ecosystems. washington dc: island press. daily, g.c., s. alexander, p.r. ehrlich, l. goulder, j. lubchenco, p.a. matson, h.a. mooney, s. postel, s.h. schneider, d. tilman and g.m. woodwell. . ecosystem services: benefits supplied to human societies by natural ecosystems. ecological society of america, issues in ecology, number . www.esa.org/science_resources/issues/fileenglish/issue .pdf. dearborn, d.c. and s. kark. . motivations for conserving urban biodiversity. conservation biology : – . kareiva, p., h. tallis, t.h. ricketts, g.c. daily and s. polasky (eds). . natural capital: theory and practice of mapping ecosystem services. new york, ny: oxford university press. millennium ecosystem assessment. . ecosystems and human well-being: general synthesis. washington dc: island press. naeem, s., d.e. bunker, a. hector, m. loreau and c. perrings. . biodiversity, ecosystem functioning and human wellbeing: an ecological and economic perspective. oxford uk: oxford university press. steiner, f. . ecosystem services—learning to leverage natural capital. arcnews : – . teeb. . mainstreaming the economics of nature: a synthesis of the approach, conclusions and recommendations of teeb. www.teebweb.org/teebsynthesisreport/tabid/ / default.aspx. science magazine www.sciencemag.org science vol may netwatch send site suggestions to >> netwatch@aaas.org archive: www.sciencemag.org/netwatch e d i t e d b y m i t c h l e s l i e r e s o u r c e s twisted logic german chemist friedrich august kekulé claimed that he discovered the ring structure of the molecule benzene during his sleep, when he dreamed of a snake eating its own tail. do the odd origins of kekulé’s hypothesis make the structure any less plausible? if you answered yes, you need a remedial session with the fallacy files. gary curtis, a philosophy ph.d. in austin, texas, compiled this encyclopedia that dissects more than common logical blunders, using cases from the media, books, politics, and other sources. for instance, attacking kekulé’s notion—or any idea—based on its history is an example of the genetic fallacy. another gaffe to avoid is the texas sharpshooter fallacy, which involves mistaken conclusions about disease clusters. >> www.fallacyfiles.org e d u c a t i o n touching the void >> it’s like the ultimate adventure game: board a spaceship, fly to a warped part of spacetime, and drop into a black hole. welcome to the visually stunning black holes: gravity’s relentless pull. this month, astronomers roeland van der marel of the space telescope science institute in baltimore, maryland, and gijs verdoes kleijn of the university of groningen in the netherlands received the € , pirelli internetional award for the educational web site. its encyclopedia offers background information on how black holes form, how long they last, and more. chairborne astronauts can zip off to destinations such as cygnus x- , where a black hole is sucking matter from a nearby star (above). there, you can perform virtual experiments such as dropping a clock into the void: it ticks progressively slower and freezes on the edge of the black hole. >> hubblesite.org/go/blackholes d a t a b a s e s fat finders they tantalize our palates, jam our arteries, and hold our cells together. they are the lipids, the chemical family that includes fats, oils, steroids, and related compounds. biochemists and other scientists can dig up data on the heavyweight molecules at this pair of sites. lipid metabo- lites and pathways strategy* comes from a u.s. consortium that aims to identify all the lipids in one cell type and measure their quantities. along with a catalog of more than lipids, the site features lab protocols, research results from consortium members, and a database of proteins that interact with lipids. lipid bank,† from the international medical center of japan and the japan science and technology agency, houses data contributed by researchers on more than molecules. the pages offer a rich mix of information, from ultraviolet and infrared spectrometry results to synthesis recipes. >> * www.lipidmaps.org † lipidbank.jp i m a g e s redrawing the world russia is the largest country by land area. but on a map that scales nations according to total births (below), it practically disappears, dwarfed by india and china. the stark contrast in child- bearing comes from worldmapper, created by researchers at the university of sheffield, u.k., and the univer- sity of michigan, ann arbor. the site turns drab demographic and economic statistics into eye-catching maps. one hundred figures size each country according to variables such as past and predicted population, number of elderly people, and oil imports. >> www.sasi.group.shef.ac.uk/worldmapper/index.html c r e d it s ( t o p t o b o t t o m ): j o h n a b b o t t /u n iv e r s it y o f t e x a s ; s p a c e t e l e s c o p e s c ie n c e i n s t it u t e ; s a s i g r o u p /u n iv . o f s h e f f ie l d a n d m a r k n e w m a n /u n iv . o f m ic h ig a n i m a g e s bug-eyed beauties wander along a stream anywhere from canada to honduras, and you might see the glittering american rubyspot damselfly (hetaerina americana; below) perched on vegetation. at odonatacentral from entomologist john abbott of the university of texas, austin, you can net data on the taxonomy and distribution of damselflies and their relatives the dragonflies. for north american states and provinces, the site offers checklists that feature interactive range maps. a field guide showcases species that buzz into texas and neighboring states. >> odonatacentral.bfl.utexas.edu published by aaas o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/ images: bug-eyed beauties doi: . /science. . . d ( ), . science article tools http://science.sciencemag.org/content/ / / . content related file:/content/sci/ / /netwatch.full permissions http://www.sciencemag.org/help/reprints-and-permissions terms of serviceuse of this article is subject to the is a registered trademark of aaas.sciencescience, new york avenue nw, washington, dc . the title (print issn - ; online issn - ) is published by the american association for the advancement ofscience © american association for the advancement of science o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/content/ / / . http://www.sciencemag.org/help/reprints-and-permissions http://www.sciencemag.org/about/terms-service http://science.sciencemag.org/ pspb .vp . / personality and social psychology bulletinbecker et al. / memory for attractiveness concentrating on beauty: sexual selection and sociospatial memory d. vaughn becker arizona state university, polytechnic douglas t. kenrick arizona state university stephen guerin redfish group, santa fe jon k. maner florida state university in three experiments, location memory for faces was examined using a computer version of the matching game concentration. findings suggested that physical attractiveness led to more effi- cient matching for female faces but not for male faces. study revealed this interaction despite allowing participants to ini- tially see, attend to, and match the attractive male faces in the first few turns. analysis of matching errors suggested that, com- pared to other targets, attractive women were less confusable with one another. results are discussed in terms of the different func- tions that attractiveness serves for men and women. keywords: evolutionary psychology; episodic memory; face recogni- tion; physical attractiveness; interpersonal perception think back to a party you attended where there were a number of people varying in sex, size, and level of attrac- tiveness. if you were asked, halfway through the party, to close your eyes and recall where particular party-goers were standing when you observed them, would your abil- ity to perform this task depend on whose location you were trying to remember? would the specific individuals you were able to best locate reflect random variations in your memory or perhaps reflect on functionally con- strained biases in the way humans process social information? functionalist evolutionary theories often posit the existence of adaptively tuned cognitive mechanisms (e.g., kenrick, ; klein, cosmides, tooby, & chance, ). thus far, however, little empirical research has examined basic questions about the particular stages of information processing at which these hypothesized mechanisms operate. studies have instead tended to focus more directly on relatively complex and “consid- ered” aspects of cognition—explicit preferences, judg- ments, and interpretations—leaving unexplored the more basic mechanisms presumed to underlie them. in the current research, we examine the extent to which particular social targets might give rise to enhanced encoding and retrieval in an ongoing episodic memory task. specifically, we present data suggesting that the sex and physical attractiveness of a person can affect how well that person’s location is remembered, using the classic matching game commonly known as concentra- tion. tasks such as the one we use here, which challenge a participant to respond as rapidly as possible to a diffi- cult task, are less susceptible to social desirability biases than questionnaires or other measures that elicit more considered responses (kenrick, ). cognizing beauty: biases in the processing of attractive others research suggests that people tend to prefer physi- cally attractive others in many social relationships, par- ticularly in those linked to mating. physical attractive- authors’ note: this research was supported by national institutes of health grant r mh , awarded to douglas kenrick, steven neuberg, and mark schaller. correspondence concerning this article should be addressed to d. vaughn becker, arizona state university, polytechnic campus, department of applied psychology, mesa, az ; e-mail: vaughn.becker@asu.edu. pspb, vol. no. , december - doi: . / © by the society for personality and social psychology, inc. ness is important in the formation of (e.g., feingold, , ), maintenance of (e.g., simpson, gangestad, & lerma, ), and satisfaction with romantic relation- ships (shackelford, ). much of the research on attractiveness has focused on explicit preferences such as actual or hypothetical choice of dates, sexual partners, or marriage partners (buss, ; kenrick & keefe, ). we have been involved in a program of research that examines more basic cognitive processes, exploring ways in which observers differentially attend to, encode, and remember other people (e.g., maner et al., , ). this research suggests that physically attractive others are treated favorably not only in terms of “down- stream” preferences and judgments but they also tend to receive biased processing at more basic stages of cogni- tion. however, the research also provided some prelimi- nary evidence that any processing advantage for attrac- tive targets might depend on whether the target is a man or a woman. in one study, maner et al. ( ) used an eye-tracking procedure to assess differential attention to targets vary- ing in sex and attractiveness. the findings revealed that when exposed to arrays of female targets, both men and women looked significantly more at good-looking than average-looking women. when exposed to arrays of men, women looked preferentially at handsome men but men showed no such bias. in another study, partici- pants were shown individual photographs of men and women and then watched a distractor film for several minutes. later, they were given a recognition memory test that included faces viewed earlier as well as similar faces not previously viewed. after this delay, beautiful women were remembered by both sexes but handsome men were not accurately remembered by either women or men. although these differential attentional and memory biases were demonstrated using different sam- ples of participants and stimuli, the findings suggested the possibility that (a) attractive others receive differen- tial processing at the level of initial visual attention but (b) only attractive women are subsequently recognized— an intriguing disjunction of basic cognitive processes. the present studies were designed to further explore the preferential processing of attractive individuals. we focus on a different type of cognitive processing in which memory and attentional processes are more temporally contiguous and in which participants are required to recall not only a target’s identity but also his or her location. the concentration game: assessing episodic memor y assessments of face recognition typically assess the extent to which a person knows that he or she has previ- ously viewed a particular face (e.g., light, hollander, & karya-stuart, ; shepard & ellis, ). recognition memory thus reflects a person’s ability to retrieve a par- ticular face stored in long-term memory. in contrast, to not only recall a face but to also remember where one saw it requires linking the face with its location. we designed the present experiments to assess (a) whether the binding process may occur more strongly when observing attractive individuals, (b) whether this depends on the sex of the person being observed, and (c) whether either a or b depends on the sex of the perceiver. to achieve these goals, we developed a com- puterized matching task designed to assess location memory for faces. the task used in the current studies is an adaptation of the classic matching game concentration. the frame- work for this task is as follows: pairs of identical playing cards are placed face down in a random arrangement and one’s task is to turn over two cards at a time to try for a match. if the cards are correctly matched, they remain face up; if not, they are turned back over and the player must try to remember the location of those two cards to facilitate a future match. the task continues in this way until all of the cards have been matched. the object of the task is to match all cards in as few turns as possible. but are all locations retrieved with equal fluency? one might expect that the locations of certain items—such as face cards or aces—are more easily matched than others. this might be due to these cards having more distinctive and discriminable physical features or due to the greater value that we tend to place on them in other contexts (such as in a game of poker). the present experiments explore whether such differences exist for different kinds of faces and contrast memory for attractive others with memory for average-looking others. overview of the current research and hypotheses selective memory for the location of physically attrac- tive others might be predicted by any of a number of the- ories of attraction, including classic social learning or social exchange formulations. for example, according to social learning models, physical attractiveness is a source of reward in others, associated with positive feel- ings (e.g., byrne & clore, ; lott & lott, ). a defining feature of a rewarding stimulus is that people work to gain access to that stimulus, and there is evi- dence, for example, that children will work harder to view an attractive person than an unattractive person (dion, ). similarly, according to social exchange theories, physical attractiveness is a particularly desir- able “asset” in deciding on a mate’s market value (e.g., walster, walster, & berscheid, ). social learning and social exchange approaches are both “domain-general” theories, and in their classical formulations, neither approach considered questions about “why” physical attractiveness was valued or focused on the possibility personality and social psychology bulletin that the reward value of attractiveness might be intrinsi- cally different for men and women. thus, these perspec- tives might lead to a straightforward prediction that attractiveness is a memorable feature in either male or female targets. from an evolutionary perspective, the desirability of any trait depends on its adaptive function, and there is reason to believe that physical attractiveness may serve slightly different functions for men and women. given that physical attractiveness has been associated with good genes and physical health (e.g., gangestad & simpson, ), one might expect that both sexes would attend similarly to physical attractiveness in opposite-sex targets (and perhaps in same-sex targets as well, to the extent that they perceived to serve as one’s sexual competitors). however, a more detailed analysis of the function of physical attractiveness suggests fundamental sex differ- ences in the significance of physical attractiveness in both opposite-sex targets and in same-sex competitors (kenrick, montello, gutierres, & trost, ). evolu- tion-based studies have generated some evidence that men place relatively greater priority on physical attrac- tiveness in choosing mates, whereas women prioritize status-linked features over attractiveness (buss, ; kenrick, neuberg, zierk, & krones, ; sadalla, kenrick, & vershure, ; wiederman, ). for example, although both men and women consider attractiveness a desirable feature in a partner (if they could have everything they want), li, bailey, kenrick, and linsenmeier ( ) found that only men priori- tized good looks when there were realistic limitations put on their choices (women instead strongly prioritized social status over good looks, if forced to choose). another series of studies found that exposure to attractive men did not affect women’s appraisals of their mates, or men’s self-appraisals, whereas exposure to attractive women undermined women’s self-appraisals and men’s appraisals of their current mates (gutierres, kenrick, & partch, ; kenrick et al., ). further- more, although both sexes are drawn to attractive peo- ple for extra-pair relationships, men are more inclined to have affairs than are women (e.g., buss & schmitt, ; clark & hatfield, ; kenrick, sadalla, groth, & trost, ). these findings converge to suggest that good-looking intrasexual competitors may pose more of a threat to women than to men (dijkstra & buunk, ; kenrick et al., ). based on these findings, one might then expect selective memory for attractive women to be exhibited by both male and female observers. in the present experiments, we test this hypothesis that facial attractiveness influences the memory for loca- tions as a function of target sex. the design of our final experiment (study ) allowed two additional hypotheses to be tested: (a) that any deficit in location memory for attractive men would occur despite relatively pro- nounced initial attention to attractive male faces and (b) that people would be relatively less likely to confuse one attractive woman for another and relatively more likely to confuse one attractive man for another. experiment method participants. participants (ps) were undergraduates ( men, women) in an introductory social psychol- ogy class who took part in exchange for extra credit. all ps had normal or corrected-to-normal vision. stimuli. thirty-two black-and-white facial photos were used (half men, half women). all faces were digitally scanned from high school yearbooks and magazines. half of these faces had been previously rated by a sample of psychology students as being average in attractiveness, whereas the other half had been rated as being very attractive. faces were selected such that facial expres- sion, hair color, head position and relative size, bright- ness, and contrast were equivalent across the different conditions of face sex and attractiveness. design. four tasks were performed in randomized order. each included eight pairs of faces of the same sex, yielding two � male arrays and two � female arrays. four of the faces in each had been prerated as attractive and four had been prerated as being of average attrac- tiveness. none of the faces appeared in more than one task. the location of squares was randomized, with one constraint: the task was designed such that ps would turn over each face once before having the opportunity to make a single match. all ps were presented with this first round of faces in identical order. ps were not aware of this task constraint, which ensured that no one could match a pair of faces by luck alone before all of the faces were viewed. procedure. ps were instructed to go to a particular web site on which the task program was located. ps first viewed an introductory web page that contained instruc- tions. ps then responded to a number of demographic questions, after which they began performing the tasks. ps first performed a practice task that involved match- ing emotionally expressive faces. then the four experi- mental tasks were performed in randomized order. the concentration game consisted of a � array of squares presented in computer array. ps used a mouse to click on one square, which revealed a face. ps then chose another square, and if the faces matched, the squares remained face up. if the faces did not match, they both returned to the face down position after s. the object of the task becker et al. / memory for attractiveness was to match all the pairs in as few trials as possible. after the last task had been performed, ps were provided an online debriefing. results the program recorded the total number of times each p clicked on the square for either of the two faces in a given pair before they were matched. thus, a lower number of turns indicated that a pair of faces was more efficiently matched. means for each factorial combina- tion of sex and attractiveness were calculated for each participant (see table ). we then conducted a within- (face sex) � within- (face attractiveness: attractive, aver- age-looking) � between- (p sex) subjects mixed-design analysis of variance (anova). results indicated that the interaction of face sex and face attractiveness was significant, f( , ) = . , p = . , partial � = . . to explore this interaction, we com- pared performance for attractive versus average-looking targets, separately for male and female targets. perfor- mance was significantly better for attractive female faces than for average female faces, f( , ) = . , p = . , partial � = . . the performance for attractive male faces, in contrast, was not significantly different than performance for average male faces, f( , ) = . , p > . . there were no significant effects associated with par- ticipant sex. discussion these results indicate that, consistent with previous evidence for biases in recognition memory, observers exhibited enhanced episodic memory for attractive women. these results are consistent with the impor- tance people tend to place on female attractiveness. men place a premium on attractive mates. women tend to exercise great vigilance to attractive female competitors. and, indeed, both male and female observers showed enhanced memory for attractive women. in contrast, no memory advantage was found for attractive male faces; they were remembered no better than average-looking male faces. this is consistent with research suggesting that women are primarily attracted to dominant, rather than physically attractive, men. it is also consistent with previous research showing that recognition memory tends not to be great for attractive male faces. experiment one limitation of experiment is that stimulus faces appeared in small arrays consisting only of same-sexed targets, which might introduce interpretational ambigu- ities when making comparisons between opposite-sexed targets. experiment examined p’s abilities to match faces within larger arrays that contained both male and female faces. method participants. all ps were undergraduates in an intro- ductory social psychology class who took part in exchange for extra credit. there were men and women, all with normal or corrected-to-normal vision. stimuli. the same face pairs from experiment were again used in experiment . design. ps played a game containing pairs of faces in an � array, with equal numbers of attractive and average male and female faces. procedure. ps performed the tasks on the internet in an instructional classroom with computers during open access hours with an experimenter or lab monitor pres- ent. ps were presented with a brief description of the tasks and written instructions on how to access them. after performing the tasks, they were automatically directed to a web page that contained the debriefing. results as in experiment , the number of turns required to complete a match served as the primary dependent vari- able. there were no main effects of interactions associ- ated with sex of participant; therefore, we collapsed across participant sex. there was a main effect of attrac- tiveness, f( , ) = . , p = . , partial � = . , and a marginally significant main effect of face gender, f( , ) = . , p = . , partial � = . . the interaction of face sex and face attractiveness was marginally signifi- cant, f( , ) = . , p = . , partial � = . , such that attractiveness facilitated episodic memory for female faces, f( , ) = . , p = . , partial � = . , whereas it bore no relationship to episodic memory for male faces, f < (see table ). discussion results of experiment corroborated the initial find- ings of experiment using a mixed-sex array. we again personality and social psychology bulletin table :experiment : mean number of trials to correctly match a face as a function of target sex, target attractiveness, and participant sex female ps male ps total m sd m sd m female face attractive . . . . . average . . . . . male face attractive . . . . average . . . . . note: lower numbers indicate better performance (fewer trials to correctly match a face). ps = participants. observed that attractive women were matched in fewer turns than average men, whereas no such bias was pres- ent for male targets. these findings again suggest that observers have a tendency to more strongly process the circumstances in which attractive women are observed, thereby facilitating subsequent episodic memory for those women. experiment in experiment , we again tested the hypothesis that people would exhibit enhanced episodic memory for attractive women. in addition, we investigated the possi- bility that, compared with other targets, attractive women might be confused with one another to a lesser extent, reflecting the individuated processing they receive (cf. taylor, fiske, etcoff, & ruderman, ). to explore this possibility, we recorded the number of times that ps incorrectly matched targets with other members of the same category (e.g., attempting to match an attrac- tive man with a different attractive man). furthermore, we explicitly investigated the possible disjunction between initial processing and subsequent episodic memory that the results of maner et al. ( ) suggested. that is, we assessed the possibility that although ps might initially attend to and process attrac- tive male targets, this processing advantage would not translate into enhanced episodic memory for those attractive faces. to detect this disjunction between initial processing and subsequent episodic memory, we incor- porated a new element to the task in experiment : all of the faces were presented in their randomly assigned locations to the participant for s at the outset of the game. thus, the first few matches provided an index of where the participant’s attention had been initially drawn. experiment also included two other methodologi- cal changes. first, we developed a larger task that con- sisted of faces of both sexes. second, we used a new stimulus set of color photographs to verify that the effects observed in experiments and were not unique to a particular stimulus set. method participants. all ps were undergraduates in an intro- ductory psychology class who took part in exchange for course credit. there were men and women, all with normal or corrected-to-normal vision. stimuli. there were color photographs, each of attractive and average female and male faces. these pho- tographs were selected from a larger set such that hair color, head position, and/or lighting differences were equally variable across the stimulus groups. procedure. ps performed this task in a perception labo- ratory in sound-attenuated booths or separate cubicles. they performed a task in which pairs of faces were randomly assigned to unique locations in a � array. before beginning the task, ps were instructed to care- fully view the faces for a short time before beginning the matching portion of the task. after pressing the start but- ton, all faces were shown to the participant for s, after which they could immediately begin matching. once they matched all of the faces, ps were debriefed and dismissed. results and discussion as in the previous two experiments, we conducted (target sex) � (face attractiveness) � (p’s sex) mixed- design anovas on matches. in addition, we performed a parallel analysis treating the proportion of within-cate- gory errors (e.g., attempting to match an attractive man with a different attractive man) as the dependent vari- able. finally, we examined the first pair of faces that each participant matched, an index of where their attention was initially drawn. correct matching performance. the main effect of target sex was significant, f( , ) = . , p = . , as was the main effect of target attractiveness, f( , ) = . , p = . . as in experiments and , the interaction between target sex and target attractiveness was significant, f( , ) = . , p < . , partial � = . (see table ). no effects were associated with participant sex, all fs < . to explore the target sex � attractiveness interaction, we compared matching efficiency for attractive versus average faces, separately for male and female targets. for female targets, attractive faces were matched more effi- ciently than average faces, f( , ) = . , p < . , par- tial � = . . the attractiveness of the male faces, in con- trast, did not affect matching performance, f( , ) = . , p = . . within-category mismatches. in addition to measuring the number of times it took ps to correctly match each pair, the task also recorded information about incorrect becker et al. / memory for attractiveness table :experiment : mean number of presentations required to match pairs of faces as a function of sex of target, attrac- tiveness of target, and sex of participant female ps male ps total m sd m sd m female face attractive . . . . . average . . . . . male face attractive . . . . . average . . . . . note: lower numbers indicate better performance (fewer trials to correctly match a face). ps = participants. trials. after ps made each initial card selection, if they then selected a face that did not match, the identity of the second face was recorded. this allowed us to exam- ine the extent to which mistakes were made within a par- ticular target category. for example, if ps confused attractive male faces with one another, this should result in a greater number of attractive male mismatches for any given attractive male face. the dependent variable for this analysis was the proportion of within-category errors for each type of target. two significant effects emerged from this analysis: there was a main effect of attractiveness, f( , ) = . , p = . , and a significant interaction between face sex and face attractiveness, f( , ) = . , p = . , partial � = . . this interaction mirrored the one found for match accuracy. ps made a lower proportion of within- category mismatches for attractive women as compared to average-looking women, f( , ) = . , p < . , par- tial � = . . for male faces, there was no difference between the proportion of within-category errors for attractive versus average-looking male targets, f < . there was a significantly greater number of these within- category mismatches for attractive male faces than would be expected by chance alone, indicating that they are somewhat confusable with one another. analysis of the first faces matched. the design of this experiment allowed us to examine which faces were matched first, an indication of which faces drew atten- tion in the first s (see table ). if all faces were equally likely to be matched first, the expected proportion for each type of face (attractive and average, male and female) would be . . this, however, was not the case. both male and female ps were more likely to match an attractive female first (for women, p = . , and for men, p = . , with a binomial test), suggesting that attractive female faces drew initial attention. attractive male faces also tended to be matched first more often than average male faces, although this pattern depended somewhat on the sex of the participant (for women, p = . , and for men, p = . , with a binomial test). combined with the overall matching performance, this finding indicates that memory for attractive male faces is no better than for average-looking men. although an attractive male face may draw the initial attention of an observer early in the game, this advan- tage does not compensate for the poor memory for the rest of the attractive male faces, which garner the worst matching performance by the end of the game. meta-analysis of studies through we performed a meta-analysis to assess the reliability of the key sex difference observed in these studies. table shows the effect sizes and significance tests for this attractiveness advantage as a function of the sex of the face (and also the sex of the participant) as well as a meta- analysis of these statistics. across these studies, the mem- ory advantage for attractiveness was highly significant for female faces and reflected a medium-sized effect. for male faces, on the other hand, there was a marginally sig- nificant reversal of this effect (with a small effect size). general discussion results of three studies revealed a strong tendency for both men and women to preferentially recall the loca- tion of beautiful female targets. this tendency was not found for handsome male targets and, in fact, there is some evidence that they were more poorly remembered relative to average-looking men. this pattern of findings fits with the view that physical attractiveness serves a dif- ferent function in men and women and meshes with a larger literature, indicating that physical attractiveness takes greater priority in decisions regarding female tar- personality and social psychology bulletin table :experiment : mean number of trials to correctly match a face, and the mismatches to faces of the same category, as a function of target sex, target attractiveness, and partici- pant sex female ps male ps total m sd m sd m mean trials to match female face attractive . . . . . average . . . . . male face attractive . . . . . average . . . . . within-category errors female face attractive . . . . . * average . . . . . * male face attractive . . . . . * average . . . . . note: ps = participants. *indicates that the value is statistically significantly different (p < . ) from . (or chance performance). table :the proportion of first matches in experiment , as a func- tion of face sex, face attractiveness, and participant sex overall female ps male ps female target attractive . . . average . . . male target attractive . . . average . . . note: ps = participants. gets than male targets (e.g., kenrick et al., ; li et al., ). in the third study reported here, in which ps were briefly shown the full array of faces before playing the concentration game, beautiful women again had an advantage on initial trials as well as on later trials. initial trials also indicated a tendency for ps (particularly women) to match handsome men more efficiently than they matched average-looking men or women. any hint of a processing advantage for attractive men, however, disappeared across the later trials, and by the end of the game, these faces appeared to be the least successfully matched. one might expect that greater attention would always lead to greater memory. yet, whatever makes attractive male faces initially eye-catching (at least to women) apparently does not translate into later recall of those faces. the higher than chance number of within-cate- gory mismatches indicates that people were retrieving locations that contained attractive men, but not the cor- rect attractive men. this pattern of findings may indicate that although particular attractive male faces may catch the eye and hold attention, without sustained attention to their identities, they are not distinct from each other in memory. in other words, a face can be distinct at two different stages of processing, distinctive in that it draws attention and distinctive in so far as it can be remem- bered and not confused with another face. beautiful women appear to be distinctive in both stages, whereas attractive men may be so only initially. there is in fact much inconsistency in the literature on memory for dis- tinctiveness and attractiveness that can be reconciled by such a view (cf. light et al., ; o’toole et al., ; shepard & ellis, ). so why are attractive men, compared to attractive women, so very “nonsticky” in memory? differential parental investment and sexual selection when considered in light of a broader network of findings, the relative differences in the memorability of attractive men and women may reflect a set of powerful principles underlying a diverse set of human and nonhu- man behaviors. one of these principles involves the intrinsic connection between differential parental investment and mate choice (trivers, ). the theory of differential parental investment in its simplest form is this: when the men and women of any given species dif- fer in their usual levels of parental investment, the sex investing more will be choosier about selecting mates; the sex investing less will compete among themselves to be chosen by the more selective sex. in most vertebrate species, women have higher mini- mal obligatory investment (e.g., female birds produce large eggs; female mammals hatch their eggs inside their own bodies and then nurse the young after they are born). hence, women generally tend to be choosier, whereas men are more intrasexually competitive. this general mammalian pattern is consistent with a number of findings on human mating. for instance, human men are quite willing to accept low-cost mating opportunities when they are offered, but females are generally unlikely to offer a mating opportunity to, or accept a mating offer from, a man who has not demonstrated either especially good evidence of his superiority over other men or, more commonly, of his willingness to invest in her and her offspring (e.g., buss & schmitt, ; gangestad & simpson, ). the sexes also differ dramatically in their interest in, and willingness to engage in, casual short-term sexual relationships (kenrick et al., ). for example, in two studies conducted a decade apart, about three-quarters of college men accepted an offer to sleep with a female stranger who approached them on campus, whereas not a single female accepted a similar offer from a male student (clark & hatfield, ). therefore, although both sexes face a mixture of costs and rewards when pursuing any desirable target (e.g., potential loss of current partner, arousing jealousy in target’s partner), the cost to benefit ratio of pursuing a physically attractive stranger is simply more unfavorable for a woman. a male stands a net increase in reproduc- tive potential with every fertile woman with whom he can successfully mate, regardless of her commitment to him; a woman, in contrast, can only have one offspring at a time. hence, before a woman is willing to consider a partner, he will generally be required to demonstrate a number of characteristics that she can only assess over an extended period of time. becker et al. / memory for attractiveness table :attractiveness memory advantage female ps male ps overall d t test d t test d t test study female faces . – . . – . . – . male faces – . . – . . – . . study female faces . – . . – . . – . male faces – . . . – . . – . study female faces . – . . – . . – . male faces – . . – . . – . . meta-analysis d z test d z test d z test female faces . . * . . * . . * male faces – . . – . . – . . note: *indicates a z test with p < . . ps = participants. humans do not have only one mating strategy, how- ever (buss & schmitt, ; gangestad & simpson, ; kenrick et al., ). although acting like typical mam- mals with regard to low-investment sexual opportunities, human men also commonly invest time and effort in off- spring care, leading men to be selective about partner characteristics. given wide variation in female fertility over the lifespan as well as individual differences in female fertility at any given age, men are presumed to maximize their reproductive potential by seeking out characteristics that signal a woman’s potential fertility. because physical attractiveness is linked to perceptions of a woman’s youth, health, and fertility, it draws the attention of both men and women (for whom it indicates the presence of a potential competitor for mates; maner et al., ). although some of the key features used by women in mate choice are also linked to a man’s physical condition, others involve social dominance and a man’s ability and willingness to invest resources in offspring, which are somewhat less available upon initial viewing. accounting for the disjunction of attention and memory may therefore require considering not only the perceiver but also the signals of attractiveness. attractive signals and their perception although physical attractiveness may provide an ini- tial and easily recognizable cue to a man’s desirability (an indication of good genes, which might therefore draw attention), it does not tend to be the key dimension on which they are evaluated as mates (buss, ; feingold, , ; kenrick et al., ), which might explain why these faces are not remembered. on the other hand, because attractiveness is a key dimension on which female faces are evaluated, attractiveness might make a female face both more eye-catching and more memorable because attractive women can be both a reproductive opportunity (for men) and a threat (to other women) in both immediate and long-term con- texts. if we assume that this sex difference in desirable mate qualities is relatively ancient—a position consistent with cross-cultural (buss, ) and transgenerational (kenrick & keefe, ) data—then attention and mem- ory systems could have evolved to reflect these different priorities. it should be noted that other cues, which tend to be more central to a man’s desirability (e.g., social dominance; buss, ), may play a greater role in determining a man’s memorability. of course, processes involved in learning likely con- tribute to these patterns of attention and memory, as well. humans undoubtedly learn that certain physical features are relatively more important to a woman’s mate value, and social dominance to a man’s mate value, which would be consistent with people’s coming to remember the location of attractive women (because they reciprocally define their place in the local hierarchy of mates) while not similarly remembering the location of physically attractive men (unless they also provide access to resources). furthermore, men may have learned that their greatest relationship threat comes from high-status and familiar men, and not from physi- cally attractive strangers, and so the dimension of attrac- tiveness may not capture whom they would be likely to remember. however, to speculate that we efficiently learn to remember faces with high social value still pre- supposes that humans actively search for what these social cues are, and thus seems to require a design fea- ture conditioned on more ultimate grounds. we have made the case elsewhere that processes of learning and evolution likely interact in this fashion (kenrick, becker, butner, li, & maner, ). it is also worth considering how signals of attractive- ness may have been sexually selected to coevolve with perceiver-based mechanisms. research suggests that one aspect of facial attractiveness is closely linked to a lack of defects—a function of facial symmetry—that sig- nals a robust immune system (gangestad, thornhill, & yeo, ). it is thus an indicator of a potential mate’s genetic fitness. by definition, then, an attractive face is closer to the prototypical face, which should make it more difficult to differentiate from other faces. consis- tent with this, it is well known that a composite face (made up of a blend of many faces) is rated as more attractive than the individual faces that it is created from (langlois & roggman, ). symmetry could be atten- tion grabbing (see enquist & arak, , for a review of how symmetry might be selected for) but it would not be a feature that would lead in a straightforward manner to greater memorability because there are fewer distinctive features to distinguish the face from others in memory. there are other signals that may act as cues for mem- ory, however. research suggests that the signs of female beauty that are endorsed cross-culturally—such as full lips and a small nose and chin—are estrogen markers and are direct indicators of a woman’s fertility and her ability to carry and nurse a child (johnston, ; johnston, hagal, franklin, fink, & grammer, ; perrett et al., ). these features distinguish physi- cally attractive women from average-looking women. indeed, there seems to be something more to female attractiveness than mere prototypicality: a composite of attractive female faces is consistently rated as more attractive than a composite of average faces (perrett, may, & yoshikawa, ). are there similar features that might make a male face stick in memory? signs of testos- terone are evident in the male jawline and brow. although there is evidence that ovulating women find these testosterone markers more attractive, this same research found that nonovulating women actually pre- personality and social psychology bulletin ferred men with more feminine features (penton-voak, jacobson, & trivers, in press). furthermore, whereas most studies have found that facial features of masculin- ity are related to perceived dominance, many find a neg- ative relationship between dominance and facial attrac- tiveness (berry & mcarthur, ; perrett et al., ). thus, for attractive female faces, there are unambiguous signals of their fertility that may make them both more attractive and more discriminable from other women, whereas the relationship between male hormone markers and attractiveness is much less clear. in sum, both perceiver-based mechanisms and sexu- ally selected signals may work together to explain why the locations of attractive women are remembered but those of attractive men are not. this suggests that male faces are revealing the default pattern—attractiveness (as symmetry and prototypicality)—is attention-grab- bing but paradoxically it may contain fewer distinctive features on which memory can operate. this disjunction does not occur for attractive female faces, perhaps because although they are prototypical, they may have additional features that signal reproductive fitness and thus are distinctive in memory as well as attention. additional questions a question remains as to the generality of the superior memory for attractive female faces. if there is a perceiver-based affordance of female attractiveness that is keyed to mate goals, then we should not expect to see these effects in populations that do not have those goals, such as prepubescent individuals and perhaps older adults. on the other hand, if it is driven by naturally selected, signal-based features, then everyone should remember these distinctive features regardless of mating-related motives. another important follow-up would examine mem- ory for attractive men by female ps who are ovulating. if the memory difference is driven by the greater confusability of this signal (and not by a perceiver-based mechanism), then ovulating women should show no greater memory for attractive men than anyone else. if, however, male facial features of attractiveness or social dominance are preferentially processed when a woman is ovulating, we could see better location recall for men with these features at this time in a woman’s cycle. there is another interesting trend that suggests potentially interesting follow-up research. when we compared the results across the different studies reported here, we noticed a tendency for attractive women to have a relatively greater advantage in subse- quent studies. one difference is that the number of faces increased across the studies and the task became conse- quently more difficult. these findings may be consistent with other evidence that intrinsically salient stimuli con- tinue to capture attention somewhat independent of the number of distractors (e.g., ohman, lundqvist, & esteves, ). this possibility that such an effect might exist for attractive female faces could be directly exam- ined in future research by systematically manipulating display size and/or the presence of other distractors. conclusion the present experiments demonstrated that memory for the spatial location of a face is generally facilitated if it is an attractive woman but not an attractive man. viewed in light of other findings on differential attention to male and female faces, and on sex differences in human mate preferences and behaviors, these findings add to a richer understanding of the ways in which simple cogni- tive processes may reflect broad underlying evolutionary principles. notes . the use of average-looking (as opposed to unattractive) faces as a control is important because unattractive others also might generate strong memories. such faces are likely to have distinctive features (the features that make them unattractive), which are likely to be easily remembered. indeed, one early study of face recognition found that both attractive and unattractive female faces were remembered better than average-looking faces after days (shepard & ellis, ). . we had participants (ps) rate how distinctive the faces from study were (specifically, how memorable or likely to stick out of a crowd) on a scale of to ( being the most distinctive). although the mean rating of distinctiveness for the six attractive female faces was sig- nificantly higher (m = . , sd = . ) than those for the average-look- ing female faces (m = . , sd = . ), t( ) = . , p < . , the mean rating of distinctiveness for the attractive male faces (m = . , sd = . ) was only marginally above those for average-looking male faces (m = . , sd = . ), t( )= . , p = . . although we do not see evi- dence that attractive male faces are rated as less distinctive than aver- age faces, this may be because ps are combining distinctiveness in terms of how eye-catching the face is (i.e., likely to pop out of a crowd) with distinctiveness in terms of how memorable the face is, estimates that are in conflict for the attractive male faces (it should be noted that ps are not very good at making meta-memory judgments; o’toole et al., , found that the correlation between such judgments and actual memory performance was only . for caucasian faces). consis- tent with this, we calculated the standard deviations of the distinctive- ness ratings for each of the faces and verified that these were larger for male faces relative to female faces using a mann-whitney u test, z = – . , p = . 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( ). parental investment and sexual selection. in b. campbell (ed.), sexual selection and the descent of man, - (pp. - ). chicago: aldine. walster, e., walster, g. w., & berscheid, e. ( ). equity: theory and research. boston: allyn & bacon. wiederman, m. w. ( ). evolved gender differences in mate pref- erences: evidence from personal advertisements. ethology and sociobiology, , - . received october , revision accepted april , personality and social psychology bulletin excision of sleeping beauty transposons: parameters and applications to gene therapy the journal of gene medicine r e s e a r c h a r t i c l e j gene med ; : – . published online march in wiley interscience (www.interscience.wiley.com). doi: . /jgm. excision of sleeping beauty transposons: parameters and applications to gene therapy geyi liu , elena l. aronovich , zongbin cui , , chester b. whitley , perry b. hackett , , * department of genetics, cell biology and development and the institute of human genetics, university of minnesota, minneapolis, mn , usa the arnold and mabel beckman center for transposon research, university of minnesota, minneapolis, mn , usa department of pediatrics, university of minnesota, minneapolis, mn , usa institite of hydrobiology, chinese academy of sciences, wuhan, p.r. china discovery genomics, inc., minneapolis, mn , usa *correspondence to: perry b. hackett, discovery genomics, inc., mckinley place ne, minneapolis, mn , usa. e-mail: perryh@discoverygenomics.net received: march revised: may accepted: june abstract a major problem in gene therapy is the determination of the rates at which gene transfer has occurred. our work has focused on applications of the sleeping beauty (sb) transposon system as a non-viral vector for gene therapy. excision of a transposon from a donor molecule and its integration into a cellular chromosome are catalyzed by sb transposase. in this study, we used a plasmid-based excision assay to study the excision step of transposition. we used the excision assay to evaluate the importance of various sequences that border the sites of excision inside and outside the transposon in order to determine the most active sequences for transposition from a donor plasmid. these findings together with our previous results in transposase binding to the terminal repeats suggest that the sequences in the transposon-junction of sb are involved in steps subsequent to dna binding but before excision, and that they may have a role in transposase – transposon interaction. we found that sb transposons leave characteristically different footprints at excision sites in different cell types, suggesting that alternative repair machineries operate in concert with transposition. most importantly, we found that the rates of excision correlate with the rates of transposition. we used this finding to assess transposition in livers of mice that were injected with the sb transposon and transposase. the excision assay appears to be a relatively quick and easy method to optimize protocols for delivery of genes in sb transposons to mammalian chromosomes in living animals. copyright  john wiley & sons, ltd. keywords footprint; mouse liver; tc /mariner; terminal repeats; transposition introduction tc /mariner transposons are a large family of dna transposable elements. they are widespread in nature and can be found in virtually all animal phyla [ , ]. recently, we reconstructed a synthetic tc -like vertebrate transposon system called sleeping beauty (sb) from inactive salmonid fish elements by a comparative phylogenetic approach [ ]. in mammalian cells, the sb transposon system is an order of magnitude more efficient than other tc family members tested [ ]. since its discovery, sb has been used in a wide range of vertebrate systems [ ] for functional genomics [ – ], germ-line transgenesis [ , , ], and somatic integration [ – ]. its higher efficiency compared to other dna-based transposable elements, its ability to accommodate large genetic cargoes [ , ], and its presumed safety compared to viral vectors make sb a potentially powerful tool for human gene therapy. the sb transposon system consists of two parts – the transposon, consisting of inverted terminal repeats (itrs), and the sb transposase that catalyzes the mobilization of the transposon. like other members of the tc /mariner copyright  john wiley & sons, ltd. excision of sleeping beauty transposons transposon family, sb transposons are mobilized via a cut- and-paste mechanism (figure a). there are two major steps involved in transposition, the excision of the trans- poson from the donor site and the integration of the transposon into the target site [ ]. excision from the donor site involves staggered, double-stranded dna breaks at each side of the transposon, which result in a small num- ber of nucleotides at the termini of the transposon being left behind [ , ]. the majority of tc /mariner trans- posons integrate into ta-dinucleotide base pairs in a fairly random manner [ , , ]. as a result of the staggered cut at the ta target sites, the transposons are flanked by ta- dinucleotides on both sides after integration (figure b), a phenomenon called target-site duplication [ , ]. the itrs of the current sb transposon came from a single tc -like element from a salmonid, tanichthys albonuibes – referred to as t. t has two inverted repeats (irs) at its termini and two ‘direct repeats’ (drs) within each ir (figure a). the outer drs, lo and ro, are located at the left and right termini of the transposon, respectively, and the inner drs, li and ri, are located further inside the transposon. both drs contain binding sites for sb transposase [ ] and the middle bp within the drs have been suggested to comprise a minimal core sequence for transposase binding [ ]. both the outer and inner drs are required for efficient transposition [ ], but they are not interchangeable, indicating that their roles in transposition are different [ ]. b a figure . the sleeping beauty (sb) transposon and its transposition. (a) structure of the terminal repeats of the sb transposon. the drs of the itrs are designated by arrowheads and are labeled according to their positions in the transposons used in this study. the boxed tas flanking the transposon result from duplication of the original ta insertion site. (b) ‘‘cut-and-paste’’ mechanism of sb transposition revised from luo et al. [ ] and plasterk et al. [ ]. the two major steps involved in transposition, excision and integration of a transposon are shown. the two broken ends at the donor sites, joined together by non-homologous end-joining (nhej) enzymes encoded by the host, leave a footprint at the donor site pcr-based excision analysis has been used to detect excision from a chromosomal location by sb transposase [ , , , ]. however, this method is not suitable for studying the mechanism of transposition because the excision is limited to a particular transposon and a particular donor site in the chromosomal position. plasmid-based excision assays, on the other hand, are more versatile and easier to perform [ , ]. hence, we developed a plasmid-based excision assay for the sb transposon system to study the different steps of transposition in more detail and found a correlation between the excision rate and the transposition rate. using this assay, we analyzed the footprints of sb in tissue-cultured cells as well as in zebrafish embryos and mice. the results of these studies directed design of a better transposon as well as led to the development of a method for determining transposition from a plasmid in organs of mice. this latter assay should be extremely useful for optimizing sb-mediated transposition reactions in mammals as a step towards harnessing the transposon for gene therapy. in such procedures, a gene contained in a transposon vector is prepared at high concentrations in a plasmid that is then delivered by any of several methods to a target organ. as a result, the sequence of the donor plasmid can serve as a common site for monitoring the excision step of the transposition reaction. materials and methods plasmids the maps and sequences for plasmids pcmvsb (also called psb ) and psb -�dde, which contain an active and inactive transposase gene, respectively, and pt/neo which contains a transposon [ ] as well as pt/hindiiineo (adam dupuy, unpublished) can be found through our website [ ]. we name pt/hindiiineo variants by the drs that are in their left and right irs. all variant pt/hindiiineo constructs were made by pcr- mediated, site-directed mutagenesis described previously for loli – lilo, rori – riro, lili – riro and lolo – riro [ ]. mutagenic primers saci + lo and bamhi + ro were used to amplify complete variant transposons on pt/hindiiineo. after digesting with saci and bamhi, the pcr fragments were ligated into the saci/bamhi vector fragment of pt/hindiiineo. all constructs were confirmed by sequencing. mutagenic primers we used are listed below with specific mutations underlined: saci + lo (aaa): ttggagctcggtaccctaaaattgaa- gtc saci + lo (caa): ttggagctcggtaccctacaattgaa- gtc saci + lo (aag): ttggagctcggtaccctaaagttgaa- gtc bamhi + ro (aaa): agctagaggatcccctaaaattga- agtcg copyright  john wiley & sons, ltd. j gene med ; : – . g. liu et al. bamhi + ro (caa): agctagaggatcccctacaattga- agtcg bamhi + ro (aag): agctagaggatcccctaaagttga- agtcg bamhi + ro (cc): agctagaggatcccccccagttgaa- gtcg saci + lo (gg): ttggagctcggtacccggcagttgaa- gtc plasmid-based excision analysis excision in hela cells: ng pt/neo or pt/hindiiineo mutation constructs were co-transfected with ng pcmvsb (or psb -�dde) into × hela cells. four days post-transfection, cells were collected and lysed in µl lysis buffer [ mm kcl, mm tris-hcl (ph . ), . mm mgcl , mm edta, . % (w/v) np , . % (w/v) tween- , µg/ml proteinase k] and incubated at ◦c for – h followed by ◦c for min to inactivate the proteinase k. for temporal analyses, µl of lysate were added to the pcr mixture [ × nh pcr buffer, mm mgcl , . mm dntp, pmol forward and reverse primer each, . µl biolase, buffer and enzyme from bioline usa]. the pcr conditions were as follows: ◦c for min, cycles of ( ◦c s, ◦c s, ◦c s), followed by ◦c for min. five µl of / dilution of the above pcr product were used for the second round pcr using nested primers and . mm mgcl ; the composition of the pcr mixture was otherwise the same. nested pcr was performed at ◦c for min, cycles of ( ◦c s, ◦c s, ◦c s), followed by ◦c for min. for pt/neo, only one round of pcr was performed and gave products of about bp. primers were: o-lac-l: ′-ggctggcttaactatgcggcatcag- ′ o-lac-r: ′-gtcagtgagcgaggaagcggaagag- ′ for pt/hindiiineo and its mutation constructs, nested pcr gave products of about bp. primers were: st round: f -ex: ′-ccaaactggaacaacactcaac- cctatctc- ′ o-lac-r: ′-gtcagtgagcgaggaagcggaagag- ′. nd round: kjc : ′-cgattaagttgggtaacgccag- ggttt- ′ i-lac-r: ′-agctcactcattaggcaccccaggc- ′. excision in zebrafish embryos: ng/µl pt/neo was co-injected with ng/µl sb mrna into one-cell-stage zebrafish embryos. sb transposase mrna was synthesized by in vitro transcription using the message machine large- scale in vitro transcription kit (ambion). the injection volume for each embryo was – nl. twenty-four hours after injection, single embryos were lysed in µl lysis buffer [ mm edta, mm tris-hcl (ph . ), µg/ml proteinase k] as described [ , ] for h at ◦c, followed by min incubation at ◦c to inactivate the proteinase k; µl of embryo lysate were used for pcr. the program used for pcr was as follows: ◦c min, cycles of ( ◦c s, ◦c s), cycles of ( ◦c for s, ◦c for s, ◦c for s) followed by ◦c for min. excision in mouse liver: dna was isolated from mm frozen liver specimens using the puregene dna purification kit (gentra systems, minneapolis, mn, usa). pcr was performed in two rounds of amplification. pcr i was carried out in a -µl reaction mixture containing µg dna, % dmso, % glycerol, pmol each forward and reverse primer, a . mm concentration of each dntp, × pcr buffer a (invitrogen, carlsbad, wi, usa), and u taq dna polymerase (promega, madison, wi, usa). pcr conditions were: ◦c for min followed by cycles of ( ◦c, s, ◦c, s, ◦c for min) with the final extension of min at ◦c. a -µl aliquot of the primary pcr product was used for secondary amplification in a -µl reaction with nested primers ( µm concentration) and the same cycling conditions except that the number of cycles was . the expected size of the amplified excision product was approximately bp. the primers used for the excision assay were outside left and right itrs. the primer sequences were: fp : ′-tgacgttggagtccacgttc- ′ rp : ′-ggctcgtatgttgtgtgg- ′ fp : ′-ctggaacaacactcaaccct- ′ rp : ′-cacacaggaaacagctatga- ′. detection and quantification of the pcr product the excision pcr products were separated on % low- melt gels (genepure sieve gqa agarose, isc bioexpress) and stained with µg/ml ethidium bromide. for better resolution and quantification, pcr products were separated on % polyacrylamide gels and stained with : dilution of sybr green i (molecular probes, inc.) for min. the gels were scanned with a storm phosphor imager (molecular dynamics) at v in the blue fluorescence mode to visualize the bands. to standardize the input total plasmid dna for each pcr, a / dilution of initial lysate was used to amplify a segment of the ampicillin-resistance gene on both pcmvsb and input pt transposon plasmid (depending on the experiment, it could be pt/hindiiineo, one of the mutants, or pt/neo). these products were separated on % agarose gel and stained with µg/ml ethidium bromide. the intensity of each band was measured in arbitrary increments of density units (integrated optical density, iod) using gel-pro analyzer imaging software (media cybernetics). the background was corrected using the filtered profile method, as instructed in the manual. the relative excision activity of the mutated transposon constructs was derived from their standardized iod, i.e., the iod of the excision band divided by the relative input template. the relative excision activity is indicated as a percentage of the excision activity of the control transposon pt/hindiiineo, for which a standard curve copyright  john wiley & sons, ltd. j gene med ; : – . excision of sleeping beauty transposons derived from the ratio of the different dilutions of the transposon was constructed. footprint sequencing to sequence the footprint, the pcr products were gel- extracted (for mutations with low excision activity, reamplified with the nested pcr), cloned into the topo ta cloning vector (invitrogen) and sequenced by the advanced genetics analysis center at the university of minnesota. transposon delivery to mouse liver the transposon-containing plasmid pt/caggs-gusb (transposon) and the transposase-expressing plasmid pcmvsb were used to assay transposition in adult mouse tissues (aronovich et al., manuscript in prep.). the transposon contains an expression cassette for the gusb gene to restore activity to mutant mice deficient in β- glucuronidase activity. the mucopolysaccharidosis (mps) type vii mice (b .c-h- bml/bybir-gusmps) were obtained from jackson laboratories (bar harbor, me, usa) and maintained in the aaalac-accredited specific pathogen- free mouse facility at the university of minnesota. the plasmids were injected into the tail vein of homozygous – -week-old mps vii mice using a -ml latex-free syringe with a / g needle. the hydrodynamics-based procedure was performed as described [ , ]. each mouse received plasmid dna in lactated ringer’s solution in a total volume equal to % of body weight. µg of a single preparation of transposon pt/caggs-gusb were injected either alone (‘treatment group ’), or with pcmvsb at : transposon/transposase molar ratio (‘treatment group ’). . µg dna were injected into all mice with pbluescript plasmid as a ‘filler’; the sham treatment control group of mps vii mice was injected with pbluescript alone. all injections were performed only once. the mice were euthanized -week post-injection, livers were harvested and frozen at − ◦c. excision assays were performed as described above. results assay for the excision step of transposition we developed and used the excision assay first in hela cells where we co-transfected the transposon plasmid pt/neo and the transposase-expressing plasmid pcmvsb (figure ). three days after transfection, the plasmids in the cell lysate were used as templates for pcr. using primers flanking the donor sites, we detected excision by amplifying a pcr product that corresponded to the size of a rejoined vector after the excision of the transposon. as shown in figure a, a pcr product of figure . schematic of the excision assay. plasmids containing a transposon and cmvsb transposase were co-transfected into hela cells. four days post-transfection, cell lysates were obtained and used for pcr with primers flanking the donor sites. the pcr products were sequenced to determine the footprints of the excision. the procedure is shown on the left and the state of the transposon and its excision product is shown on the right approximately bp was amplified in cell lysates from a pcmvsb and pt/neo co-transfection. the pcr product appeared to be specific to sb excision because neither psb-�dde, which has a mutated catalytic domain, the transposon plasmids alone, nor the transposase plasmids alone, produced the -bp product. figure b shows the accumulation of the excision products over several days. excision products were detectable h after transfection and their levels continued to rise through h after transfection. in subsequent experiments, we collected samples at h for quantification of excision events under different conditions. figure c shows the same excision assay carried out in zebrafish embryos. we co-injected transposon plasmids and sb mrna as the source of the transposase. extracts of -h embryos were used for analysis of excision by pcr. as with the cell cultures, excision was evident only in the presence of sb transposase, which supports our previous findings [ ]. footprints of sb excision we cloned and sequenced the excision pcr products to study the footprints left by the transposons. table shows the summary of the footprint sequences acquired from hela cells and zebrafish embryos. the two flanking sides of the transposon had footprints of varying lengths that we categorized in one of three ways – canonical footprint, non-canonical footprint, gap/insertion. canon- ical footprints had -bp sequences tacagta or tact- gta conforming to the model illustrated in figure b ( -bp insertions of either cagta or ctgta following copyright  john wiley & sons, ltd. j gene med ; : – . g. liu et al. table . footprint sequences from hela cells and zebrafish embryos systems category left-flanking footprint right-flanking events hela cells canonical footprints ttcgagctcggtaccc ta cag ta ggggatcctctagagt ttcgagctcggtaccc ta ctg ta ggggatcctctagagt non-canonical footprints ttcgagctcggtaccc t g ta ggggatcctctagagt ttcgagctcggtaccc ta ta ggggatcctctagagt ttcgagctcggtaccc ta c ta ggggatcctctagagt ttcgagctcggtaccc t tg ta ggggatcctctagagt ttcgagctcggtaccc ta c a ggggatcctctagagt gaps ( -bp deletion) g ta ggggatcctctagagt ( -bp deletion) ( bp deletion) insertions ttcgagct tgcatgtgggaggttttttc ggatcctctanagt zebrafish embryos canonical footprints ttcgagctcggtaccc ta ctg ta ggggatcctctagagt ttccaacncggtaccc ta cag ta gggaatcctctagagt gaps ( bp deletion) ( bp deletion) excision sites were sequenced using primers outside the transposon. short lines indicate the lost nucleotides. footprint sequences are organized in several categories. canonical footprints have -bp sequences of tacagta or tactgta, conforming to the model illustrated in figure b. non-canonical footprints have small deletions in the -bp canonical sequence. gaps have larger deletions in either or both sides of the flanking sequence as indicated. c b a figure . pcr analysis of transposon excision from plasmids in hela cells (a and b) and in zebrafish embryos (c). (a) plasmids with transposons and cmvsb transposase (pt/neo and pcmvsb) were co-transfected into the hela cells. cell lysate was obtained for nested-pcr using primers outside the transposon. �dde is a transposase without a catalytic domain. (b) time-course accumulation of excision products from hela cells. hours post-transfection are marked on top of the gel. each time point is represented by two separate transfections. the marker lane (m) on the left of the gels in a and c is a -bp ladder (new england biolabs). (c) sb mrna was co-injected into one-cell-stage zebrafish embryos with plasmids containing a transposon (pt/neo). twenty-four hours after microinjection, lysates from single embryos were used for pcr analysis. two different embryos were used in the last three categories. ∗: pt/neo plasmids mixed with embryo lysate were used as template in this case the insertion ta site). non-canonical footprints had small deletions in the -bp canonical sequences. in the case of hela cells, deletions were usually – bp. gaps had large deletions ( – bp) on either or both sides of the flank- ing sequences. in one case, we observed a -bp insertion of unknown origin between the two flanking sites. most of the footprints in zebrafish embryos were canonical footprints, whereas the footprints in hela cells consisted of similar percentages of canonical and non-canonical footprints. excision activity correlates to transposition activity a preliminary study suggested that the excision activities correlate to the transposition activity [ ]. we examined this hypothesis by measuring the excision activity of ir/dr mutations shown to have different transposition rates to evaluate its validity. to quantify the levels of excision, we generated a set of standards using dilutions of the excision lysate of the original pt/hindiiineo. as the control for the total input template, we used the amplification of a segment in the backbone of both pt and pcmvsb plasmids. for each gel scan, we first standardized the intensity of the excision bands (in arbitrary increments of density units, iod) by dividing the iod of the excision bands by the relative amount of total input plasmid. a standard curve was generated from the standardized iod values of the amplification products resulting from dilutions of the standard pt/hindiiineo. the relative excision activity for each reaction was calculated as a percentage of the pt/hindiiineo activity. figure shows one example of a gel scan and the quantification of the excision footprints. we compared these relative excision activities with the earlier reported transposition rates measured by a transposition assay [ ]. in this assay, transposon-mediated chromosome integration was indicated by the increase in the number of g -resistant colonies, and the transposition rate was measured as the percentage of the pt/hindiiineo activity. the comparisons of the activities of transposition and excision are summarized in table . mutations with high excision activities correlated with high transposition activities copyright  john wiley & sons, ltd. j gene med ; : – . excision of sleeping beauty transposons and mutations with low excision activities correlated with low transposition activities. although transposition activities varied between parallel experiments, the relative excision activities approximated transposition rates within the uncertainties of our measurements, suggesting that excision can be used as an indicator of transposition efficiency and thereby for improvement of the sb system. use of the excision assay to improve the sb transposon system the outer and inner drs have different roles in excision and transposon can be excised efficiently only at the outer drs [ ]. these results suggested that it is not the location but the differences in sequence between lo and li that gives them different functional roles. comparison of the table . comparison of relative excision activity and relative transposition rates constructs relative excision activity relative transposition rate loli − riro + �dde nd % ( %)∗ loli − riro % % ( %) rori − riro % % ( %) loli − lilo % % ( %) lili − riro nd % ( %)∗ lolo − riro % % ( %) relative excision activities were measured as described in figure . the relative transposition rates were determined as described in cui et al. [ ]. transposition rates are averages of four to seven independent transfections, numbers in parentheses show the % confidence interval. nd, non-detectable; ∗, background level of colony number. loliriro is pt/hindillneo. figure . quantification of relative excision activity in hela cell excision assay. excision levels of four ir/dr mutations were measured relative to the activity of loli –riro (the pt/hindiiineo transposon). the top gel shows excision pcr products run on a % polyacrylamide gel stained with sybr green i. the lower gel shows pcr amplification of a segment of the backbone of pt/neo and pcmvsb (or psb -�dde) as an input control for the total plasmid in the lysate. the relative excision abundance was measured as a ratio of the band intensity of the excision pcr products to that of the amplification of the segment on the plasmid backbone. ‘‘rel. template’’ indicates the relative amount of the input lysate. relative excision activity (‘‘rel. activity’’) is indicated as a percentage of control activity using the ratio for each mutation compared to a standard curve derived from the ratio of the different dilutions of the original pt/hindiiineo activity. nd, non-detectable lo and li sequences showed that there are two discrete regions in lo that are different from li, regions i and ii (figure a). to determine which region is critical for excision, we made mutations in each and tested whether the excision activity was impaired. we focused on two positions in region i because the model in figure predicts that the c in the first position (c ) and the g in the third position (g ) at the tip of lo and ro demarcate the staggered cuts. these positions, which are the same on the left and right irs, should thus be vital to the overall interaction between transposon and transposase in this region. if true, changing the nucleotides at these two positions should affect this interaction and cause reduced excision activity. figure b is a detailed analysis of positions c and g in lo and ro. in lo, when we changed either c or g , excision activity was reduced to and %, respectively, indicating that both c and g contribute to excision activity. the double mutation at both + and + reduced excision activity to below the limit of detection. the same mutations were made in ro and the effects were similar, indicating that these positions have the same functions on both sides. these data suggest that the nucleotides in the first and the third positions at the termini of the outer drs in region i are critical for excision. we tested the requirement for region ii by mutating three out of the five terminal basepairs (ttaag to gggag). comparison of figure c lanes and indicated that the exact sequence of region ii was not critical for excision because mutating these three base pairs did tt aa g (p t) g g g ag m c b a figure . terminal nucleotides in the outer drs are important for excision. (a) sequence comparison of lo and li. mutated sequences in regions i and ii are underlined. (b) mutations in region i at the first and third positions at the terminus of lo are underlined. lo(cag)li –ri(ctg)ro indicate the pt/hindiiineo transposon. quantification of the excision activity is as described in figure . nd, non-detectable. (c) mutations in region ii wherein three out of the five terminal base pairs (ttaag to gggag) were changed copyright  john wiley & sons, ltd. j gene med ; : – . g. liu et al. not reduce excision activity. instead, the excision activity seems to have been increased. the band intensity for the gggag mutation construct was eight times more intense than that of the pt (ttaag), which exceeded the limit of our detection method. this trend persisted in repeated experiments, leading us to incorporate these mutations in the next generation of improved transposon dna (unpublished). ta-dinucleotides flanking the transposon affect excision the ta-dinucleotides flanking the transposon are of special interest. sb transposons insert only into ta- dinucleotides, where a target-site duplication event leads to ta flanks on both sides of the transposon [ ]. this raised the question of whether there is a functional requirement for ta in excision. we examined this question by replacing the ta-dinucleotides flanking the transposon. we found that excision can still occur when only one flanking ta is present, although activity is dramatically reduced. when we replaced both tas, the excision rate was reduced to below the limit of detection (figure a). these results show that the tas flanking the transposon are strongly involved in excision and confirm our earlier finding of their importance in the overall transposition process [ ]. we were able to acquire complete footprints from the two mutation constructs lacking ta on one side (figure b). the footprints showed that when gg replaced the ta outside the outer dr, the substitution remained in the footprints (underlined ggs in figure b). use of the excision assay to evaluate sb activity in adult animals the sb transposon system has been used for gene transfer into mice as a model for use in human gene therapy [ – ]. however, evaluating the efficacy of transposition is difficult because delivery of transposons to many different cells of an organ results in integration events in different sites of various chromosomes. hence, we examined whether the excision assay could be used for this purpose. we used the hydrodynamic delivery method of liu et al. [ ] and zhang et al. [ ] to deliver an sb transposon to mps vii mice that were completely deficient in lysosomal hydrolase β-glucuronidase [ ]. the transposon plasmid we constructed contained an expression cassette for β-glucuronidase caggs-gusb (aronovich et al., in preparation). two groups of mice were injected with pt/caggs-gusb: treatment group received only the transposon-containing plasmid, treatment group was co-injected with pcmvsb plasmid at a molar ratio of : transposon/transposase. as in zebrafish, we detected excision events only when both transposon and transposase were injected (figure ). the pcr bands were excised from the gel for cloning and sequencing as described in the previous section. the predominant band of bp yielded eight readable sequences, seven of which gave canonical footprints of tac(a/t)gta (table ), similar to those found in zebrafish embryos and mouse es cells (table ) and one of which appeared to be a transposition event using an alternative ta excision site. another six events were sequenced from smaller, minor bands that showed deletions of various sizes and nucleotide sequences that indicated illegitimate b a figure . effect of ta-dinucleotides on excision. (a) excision analysis of ta mutations on either side and both sides of the transposon. ta lo-rota indicates the pt/hindiiineo transposon. mutations are underlined. (b) sequences of the excision site of the mutated transposons. the footprints are underlined. nd, non-detectable copyright  john wiley & sons, ltd. j gene med ; : – . excision of sleeping beauty transposons table . comparison of sb footprints in different systems canonical non-canonical footprint missing gaps/ total footprint bp bp bp insertions events reference hela cell cultures % % % % this study zebrafish embryos % % this study and [g] mouse spermatids % % % [ ] mouse es cells % % % [ ] mouse livers % % this study table . footprint sequences from mouse livers left-flanking footprint right-flanking events major band of expected size ∼ bp canonical gactcactatagggcgaattggagctcggtaccc ta cag ta ggggatcctctagctagagt footprints gactcactatagggcgaattggagctcggtaccc ta ctg ta ggggatcctctagctagagt gaps gactcacta- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - tagagt minor bands of smaller size ( bp deletion) - - - - - - - ( bp deletion) deletions ( bp deletion) - - - - - - - ( bp deletion) ( bp deletion) - - - - - - - ( bp deletion) random bp upstream of left ta, sequence continues at right itr. insertion bp upstream of left ta bp upstream of left ta continues into the complementary strand bp downstream the right ta figure . excision products in the livers of sb-transposon-trea- ted mps vii mice. lane , -bp interval markers; lane , treatment with pt/caggs-gusb alone; lane , treatment with pt/caggs-gusb + pcmvsb, lane , sham-treatment with pbluscript recombination that did not use sb transposase. taken together, the data suggest that the excision assay is useful for quickly evaluating transposition of transgenes into organs and tissues of living animals. discussion we developed a plasmid-based excision assay for sleeping beauty (sb)-mediated transposition and confirm preliminary findings that suggested that excision rates correlate to transposition rates. here we have used the excision assay as a simplified method to determine the outcome of the multi-step transposition process and to facilitate our understanding of the cis-elements required for sb excision. this pcr-based excision assay is independent of the transposon content and has shown that the excision assay can be used to monitor transposition in systems wherein drug selection is not feasible, such as in non-dividing cells of whole animal tissues. thus, the excision assay offers a high-throughput means to detect and measure transposition in somatic tissues in which multiple transposition events occur in a large number of cells. the excision assay was used to elucidate several param- eters of transposition that have not been appreciated before. the first involves footprints left in the exci- sion site. the ability to revert the transposition event after remobilization of the transposon is one potential advantage of using transposable elements in functional genomics. consequently, it is important to know whether the footprint left after excision would maintain the open reading frame for translation. two previous studies have provided conflicting results regarding the sb footprint. luo et al. [ ] observed canonical footprints in mouse embryonic stem cells, whereas fischer et al. [ ] observed non-canonical footprints in mouse haploid spermatids. in this study, we determined the footprints in tissue-cultured cells and whole animals. as summarized in table , in hela cells there is a mixture of canonical footprints and non-canonical footprints. in zebrafish, mouse embryonic stem cells and mouse liver cells, most footprints are canon- ical. in haploid spermatids, none of the footprints were canonical. together, these results show that sb leaves dif- ferent footprints in different cell types and that the ability copyright  john wiley & sons, ltd. j gene med ; : – . g. liu et al. to revert to wild type after remobilization may be lim- ited by the cell or tissue type. in zebrafish embryos, and mouse embryonic stem cells and cells of the adult liver, % of the footprints add bp (ta + cag or ctg) to the open reading frame, which should cause a frame shift. in mouse haploid spermatids, over % of the footprints add only bp, which would allow reversion to the wild- type phenotype. thus, for experimental studies, reversion to wild type would be rare when using sb in zebrafish embryos, mouse embryonic stem cells, and tissues in mice. the footprint data also showed that when gg replaced the ta outside the outer dr, the substitution remained in the footprints. this supports the current model that the ta nucleotides flanking the transposon are not part of the transposon and are not carried over into a target site. double-strand breaks generated by transposon excision are thought to be repaired by a process called non- homologous end-joining [ ]. in vertebrates, this process is catalyzed by a group of enzymes including ku and ku end-binding factors, the catalytic subunit of dna- dependent protein kinase (dna-pk), and the xrcc /dna ligase iv heteromeric complex. mutation studies in yeast have shown that loss of different subsets of these enzymes leads to different repair products, including accurate repair, inaccurate repair, and a mixture of accurate and inaccurate repair [ ]. these results resemble the different footprint patterns we observed in different cell types – mostly canonical footprints in zebrafish cells as well as mouse embryonic stem cells and liver cells, non- canonical footprints in mouse haploid spermatids, and a mixture of canonical and non-canonical footprints in hela cells. we suspect that the dna repair machineries differ in some way that leaves characteristic footprints for each cell type. this hypothesis could be further investigated by examining sb footprints in cell lines with known repair defects. the excision step we studied here is one of the major steps involved in transposition. studies from other dna transposons such as tn , tn and mu have identified the detailed steps of transposition. specifically, excision of the transposon consists of transposase-binding to the terminal repeats followed by formation of a synaptic complex comprising the transposon – transposase. for the mu transposon, this step is called transpososome assembly. the cut-and-paste reaction then occurs with first-strand nicking, hairpin formation and hairpin resolution, which releases the transposon from the donor site, and marks the end of the excision step. biochemical studies in these systems have shown that the terminal nucleotides at the transposon-donor junction are involved in steps subsequent to dna binding but before excision. in mu, the terminal nucleotides at the transposon-junction sequences are involved in transpososome assembly [ , ]. in tn , the end sequences are specifically required for synaptic complex formation [ ]. in tn , mutations in these nucleotides prevent hairpin formation and strand transfer [ ]. in sb-mediated transposition, mutations in terminal nucleotides do not affect transposase binding, but do affect excision activity, indicating they may have a similar function subsequent to dna binding but before excision as with other dna transposons. our study of nucleotides bordering the sites of excision both inside and outside the transposon suggests that the requirement of transposon-donor junction nucleotides for excision is not base-pair specific. replacement of the ta- dinucleotide, or of single nucleotides at the end of the transposon, reduced but did not abolish excision activity. these nucleotides may work synergistically. whereas point mutation at either position or at the end of the left ir reduced relative excision activity to and %, respectively, the double mutation reduced the relative excision activity below the detectable limit, about % ( % × % < %). these results suggest that the nucleotides in this region may contribute to a certain environment to affect transposon – transposase interactions. this environment could have certain physical properties required for transposase catalytic activity, similar to the one observed at the target site [ , ; g. liu, in preparation]. perturbing these interactions would result in a less favorable environment that would lead to a decrease in the rate of excision and an approximately equal decrease in the rate of transposition. if this hypothesis is true, then the flanking sequence of the transposon outside the ta-dinucleotides might influence transposon activity as well. thus, with the excision assay, we should be able to improve further the flanking sites, which, like improving the activity of sb transposase [ ], should lead to more a more powerful transposon system. our results have considerable potential for developing non-viral, transposon-mediated, gene-transfer vectors for human therapy. at present, the only method for evaluation of transposition events in organs of multi-cellular animals is to sequence insertion sites in chromosomes of treated animals because each cell in which the transposon integrates is a separate event that is non-clonal. this procedure is exceptionally labor- intensive and non-quantitative. in contrast, by employing the excision assay a few days after gene transfer, investigators will be able to approximate efficiently and quickly the levels of transposition into chromosomes of a multi-cellular organ. thus, the excision assay should be extremely useful for evaluation of parameters affecting gene delivery using plasmids as donor vehicles. acknowledgements we thank dr. akihiko koga and dr. koichi kawakami for assistance in development of the excision assay. we are especially grateful to dr. yusuke kamachi and heather gardner for instructive discussions. many thanks to stephen ekker, scott mcivor, david largaespada and other members of the beckman center for transposon research for insights and guidance and david erickson for help with the manuscript and tables. this work was supported by grants from the arnold and mabel beckman foundation and the nih (ncrr r - - and nichd p -hd ). ela was supported by a viking children’s fund grant-in-aid. copyright  john wiley & sons, ltd. j gene med ; : – . excision of sleeping beauty transposons references . plasterk rh. the tc /mariner transposon family. curr top microbiol immunol ; : – . . plasterk rh, izsvak z, ivics z. resident aliens: the tc /mariner superfamily of transposable elements. trends genet ; : – . . ivics z, hackett pb, plasterk rh, izsvak z. molecular reconstruction of sleeping beauty, a tc -like transposon from fish, and its transposition in human cells. cell ; : – . . fischer se, wienholds e, plasterk rh. regulated transposition of a fish transposon in the mouse germ line. proc natl acad sci u s a ; : – . . izsvak z, ivics z, plasterk rh. sleeping beauty, a wide host-range transposon vector for genetic transformation in vertebrates. j mol biol ; : – . . dupuy aj, fritz s, largaespada da. transposition and gene disruption in the male germline of the mouse. genesis ; : – . . horie k, kuroiwa a, ikawa m, et al. efficient chromosomal transposition of a tc /mariner-like transposon sleeping beauty in mice. proc natl acad sci u s a ; 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: – . . zhang g, budker v, wolff ja. high levels of foreign gene expression in hepatocytes after tail vein injections of naked plasmid dna. hum gene ther ; : – . . birkenmeier eh, davisson mt, bearner wg, et al. murine mucopolysaccharidosis vii: characterization of a mouse with β-glucuronidase deficiency. j clin invest ; : – . . critchlow se, jackson sp. dna end-joining: from yeast to man. trends biochem sci ; : – . . allingham js, wardle sj, haniford db. determinants for hairpin formation in tn transposition. embo j ; : – . . coros cj, chaconas g. effect of mutations in the mu-host junction region on transpososome assembly. j mol biol ; : – . . lee i, harshey rm. importance of the conserved ca dinucleotide at mu termini. j mol biol ; : – . . bhasin a, goryshin iy, steiniger-white m, et al. characteriza- tion of a tn pre-cleavage synaptic complex. j mol biol ; : – . copyright  john wiley & sons, ltd. j gene med ; : – . ecoforum [volume , issue ( ), ] lucia ailenei „Ștefan cel mare” university of suceava, , romania ailenei_lucia @yahoo.com rozalia kicsi Ștefan cel mare” university of suceava, , romania rozaliak@seap.usv.ro abstract during the postwar decades, the world economy was visibly changed by the more manifest presence of the multinational corporations; multinational companies, as the main vector of the direct investments, exert a major impact on the location or relocation of economic activities, the pattern of international trade, the dynamics of the national economies, the labor productivity etc. mncs have become important sources of technology, capital, and knowledge; their activity has a significant impact on the global distribution of wealth. strengthening the role of multinational corporations in the global economy has fueled numerous debates in the academic circles, particularly with regard to their effects on the host economies, but also to the challenges they launch on the balance of power and the position of the national states. key words: influence; multinational corporation, national state; power jel classification: f , m i. i n t r o d u c t i o n the transformations in the global business environment, strongly fueled by the end of totalitarian regimes and the political changes from the countries with former centralized economies (mostly in central and eastern europe), and by the propensity of more and more countries to economic liberalism, have considerably multiplied and diversified opportunities for multinational corporations (mncs) and have plowed the land up for their expansion (kicsi & buta, ). furthermore, the increasing role of the private sector in almost all the developing economies, the fast technological changes that transform the nature of the organizations and the international location of production, the globalization of the markets, the proliferation of regional integration arrangements etc. are added to these. in the second half of the xx century certain defining features of what we call now "the modern corporation" have been gradually developed in the global economy; the power and the influence of these entities, attested by empirical evidences (number, assets, contribution to the gross domestic product gdp, value added, international trade, foreign direct investments, etc.), as well as by the echoes in academic circles and among the public opinion, have turned them into major players in the balance of power at the global level. ii. po w er: wh a t' s i n a wo rd? the end of the cold war ( ) and the spread of the influence of the west, along with other factors (such as the differences between western and eastern civilizations, the instability of international economic and political environment, the global crisis triggered in , and so on) have not yet stabilized the balance of power at the world level, but on the contrary, they have created the premises and the conditions for the rise of new centers of power. in such circumstances, the idea of power and its forms of manifestation, long-debated by experts, sociologists and not only, have got new valences and have born new dilemmas. in its most general meaning, power is understood as the ability of an entity (a person, an organization, a government, etc.) to mold the behavior of other entities or persons. traditionally, power has reflected the ability of a state or government to enforce certain social norms (even through the use of military force when needed) for the citizens within a managed territory. a word closed to power and used frequently with an interchangeably connotation is influence. by influence we understand an action based on the authority and/or the prestige of a person and as a result of which a desired corporate power: the beauty or the beast? mailto:rozaliak@seap.usv.ro ecoforum [volume , issue ( ), ] behavior of other person is molded. in other words, influence is often viewed as a very subtle form of manifestation of the relational power. from above mentioned explanations regarding the concept of power or influence we can understand that to be exerted both involve a certain social context, i.e. they assume a relationship between at least two parties. from a historical perspective, we can talk about political, economic, military or financial power; money and wealth have always been associated with power, being considered as an attribute of those who have held the power at one time or another. it is quite difficult to anticipate how the economic power will be divided at the global level during the next decades. anyway, even the emergence of economies such as china, india, russia or other rests to a large extent on the power of corporations located there. in other words, the practice of the relations among the states in the world shows a certain "mix" between corporate power and national state power (even some forms of military power, in certain situations in which the corporate interests may coincide and/or influence political interests, including certain political decisions). joseph nye, a reputed analyst of the nature of power in the global society of today, argues the distinction between hard power, soft power and smart power (nye, ); the economic power is based on the structures established by the political decision makers, who takes into account even the coercive power (but to a smaller extent than in the previous centuries). from the perspective of the interstate relations, nye ( ) talks about three distinct types of power.  hard power, which is based on the tangible means such as military force or money; the economic position of a country, its military resources and political position are issues which shape the relations with the other countries of the world; in this category nye ( , p. ) includes the use of force, money and the negotiating capacities deriving from them. during the history, hard power of countries or empires was doubled by a similar power given to corporations (for example: british east india company, founded in , was in control of military force granted by the british empire; the dutch east india company founded in to protect the foreign trade of the dutch empire in east indies, today indonesia, etc.) (korten, , pp. - ). even now, the interests of some corporations may be above the interests of their mother-country, whereas there is a clear trend toward the rise of ”corporations without country” (korten, , pp. - ).  soft power, which is based mostly on the non-tangible means, such as institutions, ideas, values, culture and legitimacy; even if the threat of force is a non-tangible element, as nye argues, still this threat is a mean of hard power. typically, this type of power is gained by the business organizations, no matter if companies operate in a local, international or global market. the use of soft power depends to a great extent on the quality of the executives from a company and their leadership skills; according to drucker ( , pp. - ), one of the basic requirements for a leader to be effective is to gain the trust of the people around him and the faith in what we call "integrity".  smart power, which usually appear as a mix of the first two types of power. theoretically, any of these three types of power can be associated with the power held by a corporation in a specific market, in a certain region or country; the power afforded by money and economic position of an entity can take the form of a tangible element of manifestation. in order to understand who truly hold the power in the global economy we have to take into account the context in which the power is divided in the capitalist economy, the relationship between the authority of the state and the market (some questions may arise: are the coercive force of the state, wealth and moral authority of some political leaders sources of power?)(strange, , pp. ). furthermore, strange ( ) provides an in- depth analysis on the nature of power and conceptualizes two types of power, as follows.  relational power, which means conventionally the capability of an entity (a) to influence another entity (b) to do something which otherwise it would not want to do so. during a long period of history some empires (such as rome, egypt, etc.) have held a considerable relational power in the relations with other countries or territories; according to korten ( ), most often the kings or emperors have sought to obtain an absolute power, either individually or through cooperation with the church. it can be said, we believe, that this type of power is still an objective of some political leaders and/or executives who held an almost absolute power in large mncs (in a certain way, we can say that large corporations allow to their ceos and top management teams a position of autocratic power that will be exerted according to the values in which the top management believes). this type of power has been and still is attached to the position held by large corporations in the usa, europe, asia, or in other parts of the world; mncs exert this type of power in their relationship with the usual suppliers, distributors and other categories of participants to the products or services value chains.  structural power is held by those organizations and/or countries which may influence the structure of the global economy, the competition in different markets and certain inter-organizational practices; particularly the power to decide how the things must be made and to establish a framework for the relationship among the companies, as well as for those between the companies and the citizens, has become nowadays a type of power/influence that require special attention. according to strange ( ), today it is important to individuate between relational power and structural power; the distinction between economic power and political power has become of a secondary significance. for ecoforum [volume , issue ( ), ] example, as huntington ( , pp. - ) highlighted, during the greater part of its history, china was probably the most powerful economy in the world, but once with the industrial revolution the economic power has been taken over by the western world; yet, the rapid dissemination of technologies and knowledge at the global level could erode the economic power of western countries. the structural power remains directly associated with the position of the mncs in the global economy. this because different rules of operation in the foreign markets, the planning of the research and innovation activity, the organization of the distribution and promotion of products/services, along with other issues regarding the global competition are inspired or at least influenced by the practices of mncs. through the portfolio investments a lot of large companies sought to gain a certain control over production, marketing and other operations in insurance, bank, transport or industrial sectors; such investments abroad are often accompanied by inter-corporate alliances with companies from one or more countries; then such alliances, partnerships or other forms of cooperation among mncs will be able to reconfigure the competition in the various markets (gilpin, . ii i. th o u g h t s o n th e p o w er o f m nc s : po s i t iv e v i ew we want to discuss a positive view of the presence of the mncs in the global economy and global competition; this view is supported by many researches that have concluded that these entities have become real vectors of technological and socio-economic progress (these companies invest in research, technological and process innovation; use modern management practices, create a large number of jobs, etc.). still this positive view is developed on a moderate attitude regarding the role and the influence of the mncs in global economy. from this perspective, a large body of literature focuses on the link between the power gained by the mncs and the globalization of the world economy; many authors admit that this power can and must be ”bordered” by more clear regulations issued by states/governments and various international bodies/ institutions. when economic power tends to be concentrated by a small number of companies and individuals, the ”phantom wealth” became larger and more important than the ”real wealth”; korten ( ) has mainly been interested in this topic and he has explained this trend by the lack of rules in order to limit speculation, corruption and monopoly power. in a work become a gold standard in the theory of organizations, the visible hand, chandler ( ) used the examples of some of the most important modern companies and draw our attention to the way they managed to integrate the mass production with the mass distribution, the way they managed to increase their productivity and he argued that such an achievement was due to the ability of their managers/shareholders to create and manage extremely complex human organizations. in other words, companies such as ford, gm, and du pont have become organizational effectiveness "models" either for their competitors or for enterprises in other sectors; then these models have expanded rapidly through europe, japan and other countries in the world. such models have fueled a "managerial revolution" which has led to vertical organization of the business entities, decentralization of power on units and the professionalization of executive jobs (chandler, ). according to drucker ( ), the modern corporation has become a type of institution and it is based on the summation of the efforts of a large number of members in order to meet a common goal, respectively to produce goods and services in terms of maximum economic efficiency; this means leadership and a proper structure to gain profit and to regain the initial invested capital. this means ability to answer readily to threats and opportunities in the market (drucker, ). the information revolution and the knowledge revolution have changed the structure of labor force within large organizations such as mncs; knowledge and knowledge workers have become valuable assets of these companies, and their executives have to reinvent permanently the rules and the management practices in order to increase efficiency and productivity. as noted by drucker ( ), the future of mncs will take the form of corporate networks, alliances and partnerships. is this a bad or a good thing? the answer depends on the values and principles that will influence their executives' behavior and the balance between the common good and the corporate interest. drawing on extensive studies, dunning & lundan ( ) point out that practices of mncs may differ widely from one country to another, and sometimes tend to restrict competition in the local markets; the governments can and should enforce rules in order to limit such practices. all of this aside mncs play a vital role in the development of new technologies, innovations, and business networks. in a word, mncs have become one of the main vectors of the creation of wealth/prosperity in post-capitalist societies (dunning & lundan, ). the increasing role of the mncs in the global economy has become controversial, as gilpin ( ) suggests; some studies support the view that such entities ensure an efficient allocation of resources and they are vectors of economic prosperity, but others accuse the giant corporations of undermining the democracy and concerning exclusively about their profit. it is obvious, we believe, that the position and the influence of the mncs in different host countries will depend in a large extent on antimonopoly and social policies pursued by governments in these countries. ecoforum [volume , issue ( ), ] anyway, as gilpin ( , p. - ) emphasizes, during the s the public attitude toward the power of corporations has improved compared to the beginning of the postwar period. more recently, after the beginning of the global crisis in , the public perception was rather anti-corporate especially regarding banks, large investment funds and other investment companies. according to held et al. ( ) economic actors like mncs tend to concentrate an impressive economic power considering that they influence about two-thirds of world trade, technological development and other aspects of development; they have influenced the economy since the industrial revolution but they have strengthened their position of key actors during the postwar decades. particularly technological progress (such as computers, telecommunications and transport) has fueled the development of the global network of production and distribution (held, et al., ). porter ( ) maintains that companies operating in international business environment are facing more risks than companies operating in domestic markets; especially the global strategy developed by mncs will lead to the success or failure in international markets. the leadership in multinational corporations should be shaped in a certain extent by the core competencies of the organization and by the importance of innovation in an extremely dynamic business environment; porter ( ) recommends actions such as: to create pressure to innovate continuously, to develop industrial clusters, to accept local competitors, to set alliances and partnerships, etc. it is worth to mention, we believe, that certain directions of action for executives in their attempt to dominate the chaotics of business environment, directions to which kotler & caslione ( , p. ) have referred more recently, are found in the recommendations formulated by porter. more precisely, since the s porter ( , p. ) has discussed about the need for firms to establish early warning systems because businesses having such systems can receive early signals from the socio-economic environment and can act before other competitors in order to strengthen their competitive advantage in the market. table provides a brief of some of the most prominent authors' beliefs about the role and the position of mncs in global economy. table . prominent positive view: a short synopsis author the implications and benefits of mncs in global economy a. chandler jr. ( ) the modern corporation has integrated the mass production and the mass distribution, and so it took control of the product value chain, and reduced costs, increased productivity, etc. the executives' work has become some kind of "visible hand" which adjusts the competition in the markets. p. drucker ( , , ) corporations tend to integrate in some kind of confederative structures by alliances, mergers and networks; values and principles which shall apply by the top management of these confederations become of a strategic importance; they succeed to develop continuously new practices of management to valorize knowledge, qualified employees, new technologies and opportunities offered by a global market. d. held ( ) mncs have a strength position in international flows of trade, distribution, technology, isd and other essential aspects of the development of the modern economy; the host country and the mother-country try to create a favorable business environment for corporations; such organizations shall develop the global network of production aiming to gain maximum efficiency, to reduce costs and other similar issues. r. gilpin ( ) mncs play a significant role in the flows of isd among different countries, control a part of international trade, financial markets, etc.; they create new jobs, support transfer of technology, intensify competition in the local markets, etc. j. dunning & s. lundan ( ) mncs tend to concentrate the power afforded by money, technology, innovations, knowledge and other similar means; they exert a positive influence on technological capacity, r&d, employment in host countries, etc. the governments and the civil society can and should limit the non-ethical practices of corporations, their monopolist tendency, etc. porter ( , ) corporations are of a crucial significance for gaining or improving the competitive advantage of the countries due to the fact that they are organized on the criterion of efficiency, they enhance the dynamics of the business environment, develop clusters, support permanent innovation, etc. source: drawn up by the authors ecoforum [volume , issue ( ), ] undeniably mncs have gained a considerable power in the contemporary world economy; the empirical evidences attest clearly the significance of these organizations for wealth creation in post-capitalist economies; the flows of isd, exports, research, inventions and innovations, employment, etc. are linked directly to the presence of these companies in different countries of the world. but we believe that governments should and must try to limit the non-ethical corporate practices through a clear and transparent legal framework, in order to allow a proper functioning of the mechanism of the market and of competition both in the global market and in the domestic market. iv. th o u g h t s o n th e p o w er o f m nc s : th e sk ep ti ca l v i ew during the last decades in the literature on business and economics a mainstream has individualized seeking to emphasize through a suite of arguments the negative impact which the power, influence and the role of the mncs have generated in contemporary economy; a growing number of authors criticize directly the power gained by multinational corporations, some of the practices of corporate management, some non-ethical behavior in foreign markets, etc. alvin toffler ( ), characterizing the third wave in the evolution of humanity, considers that new actors play in international arena and they contribute to the significant reconfiguration of power hold by national state; this trend become more visible as the increased interdependencies among the countries of the world bring national governments in front of difficulties regarding the autonomous governance of their economies. among these "vigorous actors which defies national power", toffler ( , p. ) indicates the transnational corporation as a form of organization of production beyond national boundaries. among other negative features attached to the increased corporate power toffler ( , pp. - ) reminds us of the transfer of jobs among countries, the non-compliance with environmental protection legislation, etc. in a work also become a best-seller (when corporations rule the world), korten ( ) adopts an extremely critical position against the power and influence gained by large corporations; he considers that at the global level the real power is concentrated by corporate elite and not by the governments, and corporations do not respond in front of people, so western democracy is in danger. the originality of the corporation as a social innovation, korten ( , p. ) argues, is given by the fact that it brings together thousands of people under a unique structure that can act in order to fulfill the organizational goals, without taking into account the welfare of individuals. in capitalist society a small number of people that controls the policy and strategies of multinational corporations concentrate the greater part of the wealth, so, according to korten ( ), "the rich" become richer, and "the poor" become poorer. among other issues, korten ( , pp. - ) points out that there are certain international organizations, less known by large public, which exert considerable influence on the decisions/policies developed by the western countries; two such an organizations mentioned by korten are: a. the bilderberg commission, established in , includes a limited number of members, among which are heads of state, politicians, industrialists, bankers, intellectuals, etc. this commission meets annually, it does not have a preset agenda and not address publicly the issues discussed and the objectives concerned. b. trilateral commission was founded in mainly as a response to the ascension of japan in the global economy; it includes currently about members, its policy is relatively more transparent, it shall meet annually and shall address publicly the issues on its agenda. among the members of this commission were political figures such as the american presidents carter, bush, and clinton, and top executives of large corporations of the world (sumitomo bank, time warner, sony, etc.). korten's attitude ( , , ) towards corporate power was and still is extremely critical; he claims that these organizations hinder the competition in the markets, make use of monopolistic alliances, concentrate the power and wealth, cut jobs in order to increase their profits, apply their own ”religion” of money, ignore the standards for environment protection, ignore the common interest, affect freedom and democracy as fundamental values of humanity, etc. a considerable amount of studies have revealed that even during the turmoil of the position and the influence of large corporations have not been significantly affected, even if some companies have been facing bankruptcy; the corporate sector has expanded and has remained equally strongly in the main international markets. most of the large companies have continued to develop their expansionist strategies and their policies in order to dominate the international business environment. any society needs certain institutions to ensure the balance of power, as löpfe & vontobel ( , pp. - ) shows; from s, competitive power in different markets has been transferred from the national companies to mncs and, more important, capital markets have reached an unimaginable importance in only a few decades. in the post-crisis period the level of liquidity own by american public companies listed in the stock exchange have exceeded billion usd but it was created mainly by their foreign affiliates abroad, so wealth is created "down", at the base of the pyramid, and then it is transferred "up" (löpfe & vontobel, , pp. - ). how have we come to this situation? the current trend in the corporate business environment, as löpfe & vontobel ( ) argues, is to outsource the production in foreign affiliates abroad and to keep only certain skills and knowledge in parent company. ecoforum [volume , issue ( ), ] a highly critical point of view with regard to the current corporate power, in a certain consensus with that of korten's, belongs to john perkins, former business consultant in countries such as ecuador, peru, venezuela, panama etc. (perkins, ). the major difference between their views is that perkins focuses his critics mainly on american corporations and he pays less attention to the influence of mncs from japan, europe or other parts of the world. according to perkins ( ), certain american corporations (i.e. chevron, main, bechtel, etc.) have jointly operate with some of the american governmental agencies and with institutions such as the world bank or the imf in order to influence directly or indirectly certain political decisions and especially to exert influence on macroeconomic strategies in some latin america countries or in other poor zones of the world. korten's and perkins's criticism has some common points because both of them discuss the tendency for mncs to build a "global empire", their unprecedented financial power and their links with governmental agencies. in fact, it is possible, as these authors claims (korten, ; perkins, ), that behind the failure of certain policies for the third world and of some financing programs is to be found the influence of corporate elite (example: in ecuador, during three decades of aid the public debt of this country has increased by several times, unemployment has risen from % to %, etc.). other two authors, namely werner & weiss ( ), criticize especially the immoral practices of large corporations, the fact that even though they have codes of conduct (by which they commit themselves to the public opinion that they will apply ethical principles and which are designed as commitments that exceed the law) de facto they use some blamable practices mainly in their foreign affiliates. as it well known, during the last two or three decades significant corporations from all over the world have taken account of the corporate social responsability (csr), have drawn up quite detailed codes of conduct and they have allocated funds for the protection of the environment, supporting some projects for the disadvantaged social groups, etc. yet some assessment shows that often there is a large gap between what mncs declares publicly and decisions adopted "behind the closed doors". these two authors considers that some of the corporations from all over the world are motivated only by their annual profits, by cutting the costs of production, by gaining new markets, etc.; they accuse corporations of exploiting their employees from foreign affiliates and for non-compliance with human rights. in table we provide a brief of some of the well-known skeptical views on corporate power and its impact in global economy. table . a short synopsis of skeptical views on corporate power author the power and influence of mnc; features, negative consequences, forms of manifestation etc. d. korten ( ; ; ) the power and influence of mncs have become a danger to the western democracies and for next generations. corporations back their interests by non-ethical practice and seek only the richness of a small number of people; their power overshadows the power held by the governments, with all the consequences resulting from this situation. k. werner, h. weiss ( ) mncs are motivated only by the increase their annual profits; there is a major difference between their codes of conduct, and the csr commitments and their practices in foreign affiliates. j. perkins ( ) some of the american corporations use unfair practices to obtain contracts, concession of lands, distribution channels, etc., including with the support of governments and international organizations (world bank, imf, etc.); he talks about a corporate "empire" comparable with other colonial powers in the past. ph.löpfe, w.vontobel ( ) corporations in the financial sector (banks and investment funds, sovereign funds, etc.) have almost become "masters" of international markets; the wealth is created at the bottom level of corporate structures but shall be allocated unfairly to the top level of these structures. source: drawn up by the authors ecoforum [volume , issue ( ), ] during the last decades the evidences show that the large multinational companies have become more and more present and active in the business environment of any economies (especially developing ones). this tendency is expected to continue in the future and it could bring certain benefits, as well as negative influence on individuals, institutions and economic growth. therefore, a simple critical quotation of the today’s corporate power could be just a starting point; de facto, there is a need for international organizations, national governments and the civil society to act jointly in order to enforce some principles to rule the practices of multinational corporations in different markets. overall, even the critical and skeptical view of the power of mncs refers to certain periods during the existence of these organizations and to some contexts in which they have been non-compliant with business ethics principles. v. co nc l ud in g no t e s although large multinational corporations have a quite long history in the world economy, they have strengthened their power, especially from the end of the th century. today, the multinational corporation has become a complex and dynamic gear on a global scale with strongly interconnected components spread out in many countries. its continuous transformation is an active response to the dynamics of the global business environment articulated on its main goals, that of gaining and increasing its competitive advantage. some analysts perceive the expansion of multinational corporations as a positive force generating progress, jobs, low prices, quality products etc. others accuse these entities of exploiting workers, influencing the public policies, destroying the natural environment and harming cultural values. no matter what position we adopt, a fact is sure: global corporations have become a presence that's hard to ignore in the global business environment, and they will continue to play a significant role in the future. consistent with this tendency, the role of corporations in the global economy will become of a lesser importance than the need to adapt their behavior to the major purposes of the society, either these goals are of an economic nature or of another nature. these entities have created new competitive mechanisms and have reshaped the global business environment. at the same time, they pose a lot of questions about the role of the nation-state and they have even opened the way to erode its position in international relations. vi. r e f e r e n c e s . chandler, a. 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( ). noua carte neagră a firmelor de marcă. oradea: aquila. pii: s - ( ) - neuron, vol. , – , november , , copyright  by cell press beautiful faces have variable reward value: fmri and behavioral evidence ). the strong motivational influence of beauty has been shown in studies of labor markets suggesting that there is a ”beauty premium” and “plainness penalty” itzhak aharon, , , nancy etcoff, , dan ariely, , christopher f. chabris, , , , ethan o’connor, and hans c. breiter , , , (hamermesh and biddle, ) such that attractive indi- motivation and emotion neuroscience center viduals are more likely to be hired, promoted, and to earndepartment of radiology higher salaries than unattractive individuals (marlowe etmassachusetts general hospital and al., ; frieze et al., , ). darwinian ap-harvard medical school proaches to the study of facial attractiveness posit thatboston, massachusetts the features of beautiful faces are important biological athinoula a. martinos center for biomedical signals of mate value that motivate behavior in othersimaging (etcoff, ; grammer and thornhill, ; perrett etmassachusetts general hospital al., ; symons, ).massachusetts institute of technology and given the association between beauty and motivatedharvard medical school behavior in individuals assessing it, it is possible that theboston, massachusetts brain circuitry implicated in reward function underlying department of psychiatry motivated behavior is activated by the social signalsmassachusetts general hospital and contained in beautiful faces. research with another so-harvard medical school cial stimulus, namely money, has implicated an ex-building , th street tended set of brain reward regions with the anticipationcharlestown, massachusetts and reception of monetary outcomes (breiter et al., massachusetts institute of technology b, ; delgado et al., ; elliott et al., ;cambridge, massachusetts knutson et al., , ; o’doherty et al., ; thut department of psychology et al., ). although money and beautiful faces canharvard university both elicit motivated behaviors, money cannot elicit aes-cambridge, massachusetts thetic evaluations. in contrast, it is possible that beauti- ful faces may stimulate both reward assessments and aesthetic assessments, each leading to different pat- terns of brain activity.summary extensive neuroscience research has focused on the visual processing of faces (e.g., kanwisher, et al., )the brain circuitry processing rewarding and aversive and facial expression (e.g., breiter et al., a; morrisstimuli is hypothesized to be at the core of motivated et al., ; phillips et al., ; thomas et al., ),behavior. in this study, discrete categories of beautiful while other work has evaluated the visual processing offaces are shown to have differing reward values and symmetry (grammer and thornhill, ; perrett et al.,to differentially activate reward circuitry in human sub- ) and attractiveness (perrett et al., ; bartelsjects. in particular, young heterosexual males rate pic- and zeki, ; nakamura et al., ). in this study, wetures of beautiful males and females as attractive, but wished to evaluate faces as potential objects of reward.exert effort via a keypress procedure only to view pic- most visual stimuli are not primary reinforcers; indeed, tures of attractive females. functional magnetic reso- the sensory representation of an object is different from nance imaging at t shows that passive viewing of its rewarding properties (rolls, ). when animals or beautiful female faces activates reward circuitry, in humans respond to rewarding stimuli, they respond to particular the nucleus accumbens. an extended set of multiple informational features extracted from distinct subcortical and paralimbic reward regions also appear representations of these goal-objects, including the to follow aspects of the keypress rather than the rating rate, latency, incidence, intensity, amount, category, procedures, suggesting that reward circuitry function and proximity of the reinforcing stimuli (breiter and ro- does not include aesthetic assessment. sen, ; gallistel, ; shizgal, ). the response of animals and humans to these features appears to be introduction dependent on their hedonic deficit state regarding such reinforcers (cabanac, ). in the absence of a defined beauty in human faces has long been considered within deficit state regarding attractive faces, it remains a sa- the general category of aesthetic theory (ruskin, re- lient question whether they could be considered to be printed ; kant, reprinted ) and only recently rewarding. within the domain of biology and neuroscience. recent to evaluate this issue, we carried out a study with research on facial beauty suggests that the perception three components, each component using the same of beauty is innate (slater et al., ; langlois et al., categories of faces: beautiful females, average females, , ) and universal across race and culture (jones beautiful males, and average males (figure a). one and hill, ; cunningham et al., ; perrett et al., component involved a rating measure from (“very unat- tractive”) to (“very attractive”) to evaluate the aesthetic quality of these images. another component used a correspondence: hbreiter@partners.org these authors contributed equally to this work. novel “keypress” task to operationalize the amount of neuron et al., , ; delgado et al., ; elliott et al., ; knutson et al., , ; rogers et al., ; small et al., ; stein et al., ; thut et al., ), including the nucleus accumbens (nac), sublenticular extended amygdala (slea) of the basal forebrain, amygdala, hy- pothalamus, orbitofrontal cortex (gob), and ventral teg- mentum (vt) of the midbrain. to control for variable attention to stimuli, bold signal in a control region known to be modulated by attention, namely the fusi- form gyrus (gf) (wojciulik et al., ), was also eval- uated. results data from behavioral measures two different groups of heterosexual male subjects were exposed to two distinct behavioral tasks. one group of subjects rated facial attractiveness, and an- other group used the keypress procedure to control the duration of their exposure to these faces. rating face attractiveness eight young heterosexual males viewed the stimuli se- quentially, rating each face’s attractiveness on a scale of (“very unattractive”) to (“very attractive”). the results (figure b) showed a general effect of beauty [f( , ) � . , p � . ], a general effect of gender [f( , ) � . , p � . ], and an interaction [f( , ) � . , p � . ]. within the male and female sets, the differences between beautiful and average faces were significant (p � . ) for each comparison. most importantly, for our purpose, the difference between the beautiful males and beautiful females was not significant [t( ) � . , p � . ]. the ratings varied with exposure, such that the differ- ence in ratings between average and beautiful female faces increased from . on the first exposure to . and . on the second and third exposures; this trend figure . rating and keypress results had a significant linear component, p � . . this oc- (a) a sample of the four picture types used in these tasks (from curred because the ratings for the average faces de-left to right): beautiful female, average female, beautiful male, and creased ( . , . , and . across exposures), whileaverage male. (b) eight heterosexual males rated picture attractiveness on a – the ratings for the beautiful faces increased slightly scale. the overall mean ratings were: beautiful female . (sd . ), ( . , . , and . ). by contrast, for the male faces, beautiful male . ( . ), average female . ( . ), average male ratings of beautiful and average faces both increased . ( . ). slightly with exposure, with the difference remaining (c) a separate cohort of heterosexual males performed a task fairly steady ( . , . , and . ).where picture viewing time was a function of the number of their keypressing paradigmkeypresses. within each gender, the faces were always pre- sented in a new random order, with beautiful and average faces a separate cohort of young heterosexual males com- intermixed (ariely et al., ). the mean viewing times were: beauti- pleted the keypress task with a mean number of key- ful female . s (sd . s), beautiful male faces . ( . ), average presses per subject of (sd ), which translated female . ( . ), average male . ( . ). into large effects on image viewing times. the results (figure c) showed that subjects expended effort only to increase the viewing time of beautiful female faces.work subjects performed in order to change the relative duration they viewed the different images. the keypress for all other categories, they keypressed to make the faces disappear faster. there was a significant effect oftask evaluated whether these categories of faces had reward values that distinguished them (i.e., along the beauty [f( , ) � . , p � . ], a significant effect of gender [f( , ) � . , p � . ], and a significantdimension of reward intensity; shizgal, ). for the neuroimaging component of the study, reward region interaction [f( , ) � . , p � . ]. most importantly (and in contrast to the rating task), there was a significantactivity was evaluated using fmri at t to determine if signal changes followed the results of the behavioral difference between the beautiful males and beautiful females [t( ) � . , p � . ]. because the overalltasks. six brain regions were targeted that have been associated with reward function in animals (everitt and duration of the study was fixed ( min—allowing sub- jects to control only the allocation of time between therobbins, ; rolls, ; schultz and dickinson, ; shizgal, ) and humans (berns et al., ; breiter different categories), the number of exposures was not beauty and reward table a. random effects analysis in a priori regions tal coordinates anatomy roi r/l a/p s/i anova paired contrasts nac a � � p � . fbvsfa (p � . ) fbvsmb (p � . ) vt b � � p � . — slea c � � p � . — slea d � � � p � . — slea e � p � . — gob f � � p � . — b. random effects analysis in control region tal coordinates anatomy roi r/l a/p s/i anova paired contrasts gf g � � � p � . — gf h � � p � . — region of interest (roi) based analysis of fmri data from targeted brain regions. the talairach coordinates (talairach and tournoux, ) of maxima for the six a priori and two control rois are expressed in mm from the anterior commissure: x, right (�)/left (�); y, anterior (�)/ posterior (�); z, superior (�)/inferior (�). anova results from the interaction of gender and attractiveness are tabulated; paired contrasts are listed for anova results with p � . / clusters in hypothesized reward regions � . . gf clusters were considered separately and had to meet the same threshold. fb stands for beautiful female, fa for average female, and mb for beautiful male. constant across subjects. on average, subjects viewed roi-based random effects analysis the entire set of images three to four times, with the foci of signal change in targeted anatomic regions. pattern of results not changing with repeated viewing. data obtained at all time points during the face and fixation point phases of the paradigm were evaluated by statistical parametric analysis. six rois were identified,data from neuroimaging one in the left gob, two in the left slea, one in theinitial data analysis focused on six brain regions: the right slea, one in the left nac, and one in the right vt.nucleus accumbens (nac), sublenticular extended furthermore, two foci in opposite hemispheres wereamygdala (slea) of the basal forebrain, amygdala, hy- found in the control region of the fusiform gyrus (gf).pothalamus, orbitofrontal cortex (gob), and ventral teg- hypothesis testing via anova and contrasts: a priorimentum (vt) of the midbrain. for these targeted regions, reward regions. gender and beauty served as the pre-a region-of-interest based (roi-based) analysis was ini- dictors in the two-way anova of individual time coursestially performed using individual data (henceforth re- sampled from each roi. the anova results from theferred to as “random effects analysis”), followed by a interaction of gender and beauty are described in tablevoxel-by-voxel post-hoc analysis of data from the aver- a. only the roi in the left nac (see figures and )aged cohort. for the roi-based random effects analy- exhibited a significant general effect [f( , ) � . , p �sis, we selected all clusters of activated voxels in the . ], although two other rois suggested trends to-targeted regions that were significant in the comparison ward such an effect [i.e., the vt and slea(c)]. the pairedbetween the four face categories and the fixation point contrasts of the nac time courses were significant forbaseline. these clusters were then used as regions of the beautiful female versus average female conditionsinterest (rois) to sample individual data for an analysis and for the beautiful female vs. beautiful male conditionsof variance. for the roi-based random effects analysis, (table a). the bar graphs of average percent signaltype ii errors (false negative) might be expected in the change across subjects for these conditions (figure )case of ( ) opponent responses to different face condi- supports the results of the paired contrasts in the nac.tions, which would tend to cancel as a result of the these data (figure ) support a number of other salientaveraging of all face categories, or ( ) responses con- observations. for instance, with regard to the nac, thefined to a small proportion of face conditions, which signal change in the average male condition is secondwould tend to be diluted by such averaging. thus, a only to that of the beautiful female faces and is notpost-hoc parametric analysis (i.e., using t statistics) was significantly different than it. it is also notable that signalperformed on a voxel-by-voxel basis using data aver- profiles in the vt and one focus in the slea(c) resembleaged across the cohort (henceforth referred to as “fixed the signal profiles between the beautiful female condi-effects analysis”) to determine if differential patterns of tion and the average female plus beautiful male condi-reward circuitry activation paralleled results from the tions in the nac, even if not significant by the analysistwo behavioral studies. general effects for beauty and of variance (table a). one other focus of signal changegender were each evaluated, followed by their corre- in the slea(d) also qualitatively resembles those in thesponding specific effects: beautiful female versus aver- nac [and vt plus slea(c)], but differs with regard toage female and beautiful male versus average male (i.e., signal change in the average male condition. in general,beauty effects), along with beautiful female versus beau- there is a qualitative resemblance between the keypresstiful male and average female versus average male (i.e., gender effects). results for the beautiful female, average female, and neuron figure . bar graphs of mean percent signal change and standard deviation from the six rois selected for the random effects analysis percent signal change is presented, relative to the experimental baseline, for each of the stimulus conditions: beautiful female, aver- age female, beautiful male, and average male faces. note the similar signal profiles for the first three bars in each graph for the nac(a), vt(b), slea(c), and slea(d). beautiful male conditions, and signal changes for these of table ) contains roi c (table a) of the random effects analysis. all of these foci of signal change, withthree conditions in the nac, slea(c), slea(d), and vt. hypothesis testing via anova and contrasts: control the exception of the right slea focus of negative signal change (table , #a ), coincided with foci of signalregion. the anova results from the interaction of gen- der and beauty are described in table b, and no rois change observed in the comparisons for the two specific effects that follow.exhibited a significant general effect. fixed effects (post-hoc) analysis of average data specific effect for beauty: beautiful versus average female comparison. for this contrast, four clustersa number of reward regions produced significant signal change (p � . ) for the general effects of beauty were observed with significant positive signal changes: two in the right gob, one in the left gob, and one inand gender and the specific effects of the interactions between beauty and gender. the following sections are the right nac (table ). four foci of subthreshold positive signal change were further observed in the left nac,organized around the general effects with specific ef- fects (interactions) following. bilateral slea, and right vt. three foci of significant negative signal change were observed: one in the rightgeneral effect of beauty: all beautiful versus all aver- age face comparison. the general comparison of all gob, and two in the left gob. of these activation foci, four directly correspond tobeautiful versus average faces revealed four clusters of significant positive signal change in the right gob, right foci observed in the general contrast for beauty. in par- ticular, activation in the vt, slea (see figure ), andslea, and bilateral vt. one focus of subthreshold posi- tive signal change (p � . ) was further noted in the gob (table , #b , b , b , b ) is common to both, although one slea focus is countered by an activationleft slea. two foci of significant negative signal change were observed in the bilateral slea, one of which (row of opposite valence from the beautiful male versus aver- beauty and reward t a b le . p o st -h o c f ix e d e ff e c ts a n a ly si s c o n tr a st a b c d e f g e n e ra l b e a u ty b f –a f b m –a m g e n e ra l g e n d e r b f –b m a f –a m a n a to m y n u m b e r r –l a –p s –i p v a lu e r –l a –p s –i p v a lu e r –l a –p s –i p v a lu e r –l a –p s –i p v a lu e r –l a –p s –i p v a lu e r –l a –p s –i p v a lu e n a c a n d o th e r v s � . e � � . e � � . e � * � � . e � � � . e � * � � . e � � . e � � � . e � � � . e � v t � � � . e � � � � . e � � � � . e � * � � � . e � � � . e � � � . e � * � � . e � � � . e � * � � . e � s l e a � � . e � � � . e � * � � . e � � . e � � � � . e � � � . e � * � � � . e � � � . e � � � � . e � � � � . e � � � � � . e � g o b � . e � � . e � � � . e � � . e � � � . e � � � . e � � � � . e � � � � . e � � . e � � � . e � � . e � � . e � � � . e � � � . e � a m yg � � � � . e � * � � � . e � * � � � . e � * � � � . e � * � . e � * � � . e � * h yp o � � . e � * � � . e � a c ti va ti o n c lu st e rs a re id e n ti fi e d b y p o st -h o c vo x e l- b y- vo x e l a n a ly si s. “a n a to m y” lis ts th e si x ta rg e te d re w a rd re g io n s, in c lu d in g p u ta ti ve b ro d m a n a re a (b a ) w h e re a p p ro p ri a te . a c ti va ti o n s a re id e n ti fi e d b y ro w n u m b e r (n u m b e r) a n d sp e c if ic su b tr a c ti o n (a –f ). t h e se su b tr a c ti o n s in c lu d e th e g e n e ra l c o m p a ri so n s fo r b e a u ty a n d g e n d e r a n d th e ir a ss o c ia te d sp e c if ic c o n tr a st s: b e a u ti fu l fe m a le ve rs u s a ve ra g e fe m a le (b f –a f ), b e a u ti fu l m a le ve rs u s a ve ra g e m a le (b m –a m ), b e a u ti fu l fe m a le ve rs u s b e a u ti fu l m a le (b f –b m ), a n d a ve ra g e fe m a le ve rs u s a ve ra g e m a le (a f –a m ). t a la ir a c h c o o rd in a te s (t a la ir a c h a n d t o u rn o u x , ) o f th e se a c ti va ti o n fo c i a re lis te d , a n d m a x im a p va lu e s a re ta b u la te d , w h e re “e ” st a n d s fo r e x p o n e n t, su c h th a t . e � m e a n s . � � . a c ti va ti o n c lu st e rs a re lis te d th a t p ro d u c e d si g n if ic a n t p o st -h o c e ff e c ts p e r a p va lu e th re sh o ld c o rr e c te d fo r th e vo lu m e o f vo x e ls sa m p le d in a p ri o ri ta rg e te d re g io n s. a c ti va ti o n s w it h a st e ri sk s d id n o t m e e t th is c o rr e c te d th re sh o ld b u t h a d m a x im a w it h . � � � p � . � � . a c ti va ti o n s a re re c o rd e d in th e sa m e ro w if th e ir fo c i a re w it h in c m o f e a c h o th e r; so m e c o n tr a st s h a ve m u lt ip le fo c i p ro x im a te to fo c i in o th e r c o n tr a st s, in w h ic h c a se , th e fo c u s w it h th e c lo se st m a x im u m to th e o th e rs is p la c e d in th e ro w w it h th e m . neuron figure . post-hoc analysis (for general ef- fects of beauty, along with its specific con- trasts) bilateral activation of the slea in the general contrast of all faces versus baseline (first row) and the general and specific effects of beauty (rows – ). rows and are the positive and negative results of the general effect of beauty (b versus a). row shows the positive activation for the comparison of beautiful fe- male faces versus average female faces (bf versus af), and the negative activation (row five) for the comparison of beautiful male faces versus average male faces (bm versus am). the slea activation (rectangles) in the contrast of all faces versus baseline and the general effect b versus a, coincided with the foci of signal changes observed in the comparison for the specific effects (bf versus af, and bm versus am). note that activations in the specific contrasts are additive and are thus observed in the general contrast. age male conditions. also, clusters in rows , , and one focus of positive signal change and one focus of negative signal change directly correspond to foci of(table ) contain rois a–c (table a) of the random effects analysis. positive and negative signal change observed in the general contrast for beauty. in particular, activation inspecific effects for beauty: beautiful versus average male comparison. for this comparison, one focus of the vt and slea (see figure and table , #c and c ) is common to both. also, clusters in rows and significant positive signal change was identified in the left vt (table ). four clusters of significant negative (table ) contain rois a and c (table a) of the random effects analysis.signal change were further observed in the left slea (n � ), and the bilateral nac/ventral striatum. the nac/ general effect of gender: all female versus all male face comparison. the general comparison of all femaleventral striatum foci had maxima in the ventral striatum with their clusters covering the nac (e.g., see figure , versus all male faces revealed no foci of significant acti- vation. subthreshold foci of positive signal change werebottom row images for one such example). beauty and reward observed in the left amygdala, right hypothalamus, and tified measures of reward valuation, particularly for beautiful male faces. this dissociation between assess-left vt. a subthreshold focus of negative signal change was also observed in the left amygdala (table ). all of ments of attractiveness and quantified measures of re- ward resembles that described by berridge ( , )these foci of signal change coincided with foci of signal change observed in the comparisons for the specific regarding the processes of “liking” and “wanting” (also see ariely and loewenstein, ). second, the key-effects that follow. specific effect for gender: beautiful female versus press procedure revealed that a category of visual stim- ulus that is not linked to any post experiment asset orbeautiful male comparison. for this contrast, seven clusters were observed with significant positive signal reward, namely beautiful female faces, can be rewarding without being associated with any clear hedonic deficitchange in the left gob, bilateral slea, left nac/ventral striatum, left nac, and right vt (n � ) (table ). one state. third, the fmri experiment revealed a significant re-focus of subthreshold signal change was observed in the right nac. three foci of significant negative signal sponse in the nucleus accumbens to the beautiful fe- male faces by both random effects and fixed effectschange were observed in the bilateral gob and left slea, while one focus of subthreshold signal change analyses. the fixed effects analysis further indicated that regions such as the ventral striatum proximate to thewas noted in the amygdala. although none of these activation clusters account nac, along with the vt, slea, and gob, also produced significant activation with regard to the same stimulusfor the foci observed for the general effect of gender, five of them directly overlap foci of opposite signal change conditions. both the random effects (figure ) and fixed effects analyses (table ) revealed relative positive sig-observed in the contrast of average female versus aver- age male faces described below. an example of this nal changes in the nac for heterosexual males viewing rewarding faces (i.e., beautiful female versus averagecountervalanced signal change in the left nac/ventral striatum can be observed in figure . also, clusters in female conditions) and relative negative signal changes for nonrewarding faces (i.e., beautiful male versus aver-rows , , and (table ) contain rois a–c (table a) of the random effects analysis. age male conditions). these results have some analogy to the negative deflection in bold signal reported forspecific effects for gender: average females versus average males. for this comparison, six foci of signifi- part of the nac in response to painful thermal stimulation versus a nonaversive baseline (becerra et al., ).cant positive signal change were identified in the right gob (n � ), left gob (n � ), right hypothalamus, and in conjunction with results of human neuroimaging work using drug, gustatory, tactile, and monetary stim-left vt (table ). subthreshold positive signal change is observed in the bilateral amygdala and right vt. regard- uli, these beauty results strongly support a fourth point, that at the spatial scale of subcortical nuclei and theiring significant foci of negative signal change, three foci are observed: in the right nac, left nac/ventral striatum, cortical projection fields, there appears to be a general- ized circuitry processing rewarding stimuli.and left slea. one focus of subthreshold negative signal change is noted in the left amygdala. lastly, the fmri data suggest a hypothesis for further study regarding the potential effect of “liking” andof these activation foci, three foci of positive signal change and one of negative signal change directly corre- “wanting” on these brain reward regions (berridge, , ). specifically, we observed patterns of activationspond to foci of subthreshold signal change observed in the general contrast for gender. in particular, activa- from four of six rois in the nac, slea, and vt that generally follow the keypress results for the beautifultion in the amygdala, hypothalamus, and vt (table , #f , f , f , f ) is common to both. the negative female, average female, and beautiful male conditions (figures c and ). the observation of similar signalsignal change in the right nac and left nac/ventral stria- tum (table , #f and f ; see figure ), along with three profiles across multiple reward regions resembles re- ports of similar signal changes across a distributed setother foci of negative and positive signal change (table , #f , f , f ), directly overlay oppositely valanced of reward regions with money (breiter et al., ). al- though the outcomes for the behavioral tasks and fmrifoci of signal change in the contrast of attractive female versus attractive male faces described above. it is also procedure were not perfectly symmetric, no reward re- gion per se mirrored the outcomes of the rating experi-notable that clusters in rows , , and (table ) contain rois a–c (table a) of the random effects analysis. ment (figure ). the fixed effects analysis supported the random effects analysis by showing that components of the nac, slea, and vt paralleled the keypress data withdiscussion regard to subtractions between the beautiful female, average female, and beautiful male conditions (figureoverview ). these results suggest that reward regions respondthe goal of this study was to provide evidence for sepa- primarily to the reinforcing characteristics of a subgrouprable measures of aesthetic versus rewarding qualities of the faces rather than to their aesthetic components.in beautiful faces and to provide an initial understanding of the neural mechanisms that underlie these qualities. to reach this goal, we carried out both behavioral and dissociation of rewarding and aesthetic behavioral responsesfmri experiments involving the visual assessment of beautiful and average faces. the results of these experi- heterosexual male subjects rated beautiful male faces as very attractive but did not expend effort to increasements produced five primary points. first, the rating and keypress tasks revealed a dissoci- the viewing times of these faces. the most reasonable inference is that they found them aesthetically pleasingation between assessments of attractiveness and quan- neuron figure . post-hoc analysis (for general effects of gender, along with its specific contrasts) activation of the left nac in at least two of three contiguous brain slices for the contrast of all faces versus baseline (row ) but not the general effect of gender (rows and for positive and negative signal changes, respectively). row shows the positive signal changes from the comparison of beautiful female faces versus beautiful male faces (bf versus bm), while row shows the negative signal changes of the comparison of average female faces versus average male faces (af versus am). activation in the left nac (in boxes) can be observed as foci of opposite signal change (positive bf versus bm, and negative af versus am). this explains the absence of this activation in the general effect of gender. but not rewarding, in contrast to their ratings and behav- static, intrinsic property, but is rather a function of the animal’s internal state at the time and of its past experi-ior regarding beautiful female faces. these observations suggest that the ratings procedure and the keypress ence with the stimulus. primary homeostatic functions lead to drives such as eating, drinking, and thermal regu-procedure measure aesthetic value and reward value respectively. the keypress results further indicate that lation on the basis of deficit states, or changes in physio- logical conditions. in the current study, the beautifulvisual stimuli can have reward value by an objective measure, namely work performed to increase or de- female faces were rewarding without reference to a spe- cific deficit state, post experiment asset position, orcrease exposure time to different images. in general, the reward value associated with a stimulus is not a object that could potentially impact on internal physio- beauty and reward men like to watch beautiful women’s faces; however, it was not obvious that this class of stimuli would activate the classical reward circuitry that has previously been associated with drug rewards, homeostatic rewards, and monetary rewards, all of which have direct physio- logical implications or can be readily transformed into goal-objects with physiological effects. this is a critical issue since many literatures outside of neuroscience consider facial attractiveness as a social construct that is not necessarily tied into the function of fundamental reward circuitry (reviewed in etcoff, ). in the random effects analysis of roi data from the six targeted reward regions, only the nac met our corrected statistical threshold and produced subsequent pair- wise comparisons for contrasts involving signal col- lected during the observation of beautiful female faces. the nac, like the fusiform gyrus (gf), was one of the few brain regions to even meet a bonferroni thresholdfigure . a summary of the behavioral and bold signal results (p � . � � ) for the general contrast of all facefor the specific effects of beauty and gender conditions versus baseline used in the roi-selectionthe left table in the figure shows “p � . ” when the difference in the results from the rating and keypress tasks is statistically signifi- procedure (breiter et al., , ). the nac achieved cant and shows “ns” when it is not. the table on the right describes this despite having counterposed activation for condi- the bold signal changes in the following reward regions: ( ) right tions that were nonrewarding versus conditions that nac (activation clusters listed in row of table ), ( ) region of the were rewarding (see figure ). in contrast to the nac, left ventral striatum proximate to the nac, including the nac (nac/ the fusiform gyrus (gf) evidenced two foci of boldvs) (this includes the maxima that was localized in the nac via the signal change in the comparison of all face conditionsroi selection procedure for the random effects analysis as roi a versus baseline; however, the sex by beauty interactionin table a, and the cluster localized over a larger area from the fixed effects analysis that is listed in row of table ), ( ) left slea was not significant for either of these rois in the analysis (this is roi c in table a that was localized in the slea via the of variance. bold signal change in the gf in response roi selection procedure for the random effects analysis, and the to faces has been reported to be affected by alterations activation clusters listed in row of table from the fixed effects in attention (wojciulik et al., ). the absence of signif- analysis), and ( ) right and left vt (this is roi b in table a that icant contrasts between conditions in the gf for thiswas localized in the right vt via the roi selection procedure for the sample of subjects argues that the significant effectsrandom effects analysis, and the activation clusters in rows and of table from the fixed effects analysis for the right and left vt, observed in the nac were not strictly due to differences respectively). activation in brackets were subthreshold per table in subject attention to stimuli. . in viewing this summary table, it is important to consider the given the keypress results, the observation of nac comparisons as tentative, since there is not perfect parallelism be- activity in response to beautiful female faces implicates tween the behavioral data and imaging data (see discussion). with it in the assessment of reward value. since the classicthis in mind, the bold signal in the nac, nac/ventral striatum (nac/ formulation of a dedicated reward circuitry (wise et al.,vs), slea, and vt produce positive signal changes when p � . ; louilot et al., ), the meso-accumbens dopa-for the keypress task (emphasized with text in bold tone). these regions also alternate signal valence across conditions, while vt mine pathway has been considered a central component activation switches laterality; these observations suggest a need of circuitry processing the reinforcing effects of most for greater dynamic range in the behavioral tasks to fully determine goal-objects. recent work further suggests that the nac their correspondence with reward circuitry signal change. has complex reward functions, including the assess- ment of reward expectancy (schultz et al., ; berns et al., ; breiter and rosen, ; breiter et al., ; logical signals. further work is clearly needed to evalu- schultz and dickinson, ; knutson et al., ). the ate alliesthesia effects (cabanac, , ) for this current work extends the set of categories of stimuli category of stimuli. further behavioral tasks are also producing nac activity beyond homeostatic, monetary, needed to evaluate informational features not assessed and drug rewards, to include rewards with direct social in the current study. for instance, it is possible that relevance, such as beautiful faces. young heterosexual males experience the perception fixed effects analysis of averaged data was further of beautiful males in a more aversive fashion than the performed to determine if other reward regions pro- perception of average males, as suggested by the corre- duced differential patterns of activation that paralleled spondence of nac signal change between beautiful the dissociation of effects for the beautiful face condi- male and average male faces, to nac signal change tions in the behavioral studies. indeed, distinct profiles between aversive and nonaversive thermal stimuli (be- of signal change were observed for the general contrasts cerra et al., ). regarding beauty and gender in other reward regions besides the nac and proximate ventral striatum (i.e., reward circuitry activation to facial stimuli nac/ventral striatum), namely the slea, vt, and gob. one goal of this study was to determine if beautiful of these regions, no focus of signal change met our faces, or a subgroup thereof, motivated behavior on post-hoc corrected statistical threshold for the general one hand, while on the other producing reward circuitry effect of gender (table ). this appears to be partly due to the counterposing of activations (see figure ) in theactivity when passively observed. it is not surprising that neuron specific contrasts of beautiful women versus beautiful effects analysis in that three of these clusters overlap men and average women versus average men (table ), rois in the nac(a), vt(b), and slea(c) used in the ran- thus reducing their additive effect for the general effect dom effects analysis (table a and figure ). if one of gender. in the case of beauty, the general effect looks at all of the contrasts for the specific effects of largely reflected additive inputs (see figure ) between beauty and gender, one notes that the bold signal in responses for beautiful women versus average women the nac, nac/ventral striatum, and slea alternate signal and beautiful men versus average men (table ). valence across conditions, while vt activation switches alongside the observations in the nac, nac/ventral laterality (table and figure ). suggestions that these striatum, and vt, the post-hoc observations of signal activations follow the outcomes of the keypress task change in the gob and slea is consistent with exten- are not warranted, though, since there is a potential sive animal experimentation. gob neurons in the rat discrepancy between bold signal produced in the nac, (schoenbaum et al., ) and monkey (rolls, ; slea, and vt (e.g., rois a–c in figure ) during the schultz and dickinson, ) fire during the anticipation average male condition and the keypress results for that and experience of positive and negative outcomes. fur- experimental condition (figure c). behavioral work to thermore, the responses of gob neurons may represent characterize responses to the average male faces may relative reward preferences (schultz and dickinson, be helpful in this regard. furthermore, future studies ). this latter observation has particular relevance with more sensitive behavioral experiments might con- to the current data showing gob activation for subtrac- sider use of the same subjects for both behavioral and tions involving beautiful female faces compared to other imaging tasks to allow quantitative evaluation via multi- face conditions. the presence of gob activity in the variate analysis of these observations. average female versus average male subtraction may the keypress task indicated a significant difference also be similarly interpreted if one assumes the behav- between categories of faces when one of the categories ioral tasks did not have enough dynamic range to distin- was that of the beautiful female faces (which was the guish a preference for average females over average only condition to be positively reinforcing). the other males. alternately, the gob activation associated with three categories of faces were actively suppressed (thus this contrast could reflect the assessment of conflict indicating that they were mildly aversive). the presence between options connected to the stimuli, as has been of positive and negative nac signals for contrasts involv- shown to be important for choices between gambling ing reinforcing rewards versus contrasts involving non- positions (bechara et al., ). rewards (i.e., aversive outcomes) has an intriguing paral- neurons in the slea are activated by rewarding brain lel to data indicating positive bold signal changes to stimulation in the rat (arvanitogiannis et al., , ; rewards (such as cocaine and morphine; breiter et al., flores et al., ; nakahara et al., ; shizgal, ). , ), and the report of negative bold signal furthermore, lesions of the slea reduce the rewarding changes to painful stimuli (becerra et al., ). given effect of stimulation to the medial forebrain bundle (ar- that the changes in signal observed for rewarding and vanitogiannis et al., ), reduce cocaine self-adminis- nonrewarding outcomes is dependent on expectancy tration (robledo and koob, ), and disrupt operant conditions (breiter et al., ), such differences in sig- performance for sucrose pellets in rats (brown et al., nal valence in the nac and other reward regions may not ). data from other human studies also suggests that be absolute but represent a relative ordering of signal the slea, gob, and vt may respond to nonrewarding associated with the experimental conditions. stimuli: transient activation in these regions has been reported following painful thermal stimulation (becerra general circuitry of reward and its activityet al., ). during aesthetic assessmentthe patterns of signal change observed in reward a similar set of brain reward regions appears to respondregions with the random effects and the fixed effects in common to very distinct categories of reward. at theanalyses suggest some potential parallels with the be- spatial scale offered by current neuroimaging methodol-havioral tasks (figures c, , and ). such comparisons ogy, at least five brain regions (plus or minus the hypo-must be considered tentative since there is not perfect thalamus, and the ventral striatum proximate to the nac)parallelism between the behavioral data and imaging have been implicated in the perceptual assessment ofdata in that the imaging data has a broader scale of rewarding stimuli. in particular, the nac, slea, amyg-measurement and thus greater sensitivity (suggesting a dala, gob, and vt have all been implicated in expec-need for greater sensitivity of measurement in future tancy functions (breiter et al., ) and to various de-behavioral tasks). signal change from some of the rois grees in the processing of positive and negative(e.g., rois a–d from table a and figure ) used in the outcomes. in human neuroimaging studies, stimuli lead-random effects analysis suggest a qualitative similarity ing to significant signal changes in these regions haveto a subset of results from the keypress procedure (i.e., included drugs such as cocaine, nicotine, amphetamine,the beautiful female, average female, and beautiful male and morphine, pleasant or aversive tastants, pleasantconditions) (figure c). the results of the fixed effects tactile stimuli, and monetary rewards (berns et al., ;analysis support this observation, in that clusters of breiter et al., b, , , , ; breiter andactivation in the right nac (row of table ), left nac/ rosen, ; delgado et al., ; drevets et al., ;ventral striatum (row of table ), left slea (row of elliott et al., ; francis et al., ; knutson et al.,table ), and right vt (row of table ) produce positive , ; o’doherty et al., ; rogers et al., ;signal changes for comparisons between conditions small et al., ; stein et al., ; thut et al., ;that are significant for the keypress task (figure ). these results support the observations of the random zald et al., ). such congruence of findings between beauty and reward brain regions producing responses at the spatial scale limitations a number of limitations apply to this fmri study (seeof cubic millimeters of tissue and reward stimuli that breiter et al., a, c, , ). these issuesinduce activity in these brain regions supports the thesis include the limited signal-to-noise ratios of bold sig-of a common generalized circuitry that processes re- nals recorded from small subcortical structures, spatialward information across category and dissects discrete resolution after data analysis, and magnetic suscepti-features of such stimuli for the planning of behavior bility.(breiter and rosen, ; breiter et al., ). future particular to this study, it is important to note thatstudies face the challenge of dissecting the relative con- participants in all three experiments were young hetero-tributions of these distributed brain regions to the as- sexual males. recent evidence suggests that women’ssessment of reward and aversion, and the organization facial preferences may change across the menstrualof behavior around these assessments. cycle. penton-voak et al. ( ) have found that womentogether with the contrasting results of the rating and in the follicular phase of the menstrual cycle are morekeypress procedures, our fmri results suggest a hy- attentive to phenotypic markers indicating immunocom-pothesis that aesthetic evaluation may be separate from petence and therefore prefer stereotypically “mascu-reward assessment; although both might follow a com- line” faces more than they do at other times of theirmon early step in valuation of potential goal-objects (i.e., cycle. given the more complex results of human femaleof their reward intensity) (breiter and rosen, ). initial preferences, we decided to conduct this initial investiga-inspection of results from the fixed effects analysis sug- tion with male subjects only. thus, these results shouldgests that the vt, slea, and gob may be associated not be generalized to women, nor to individuals with awith the general effect of beauty. of these regions, one different sexual orientation.focus in the slea (table , #a ), in particular, is unique finally, it is possible that the difference between theto the general effect and cannot be accounted for by two behavioral tasks was not caused by a differencethe subsequent specific effects. such an interpretation between aesthetic evaluations and motivation but ratherwould be supported by the fact that the slea and vt was a result of scaling changes in the ratings task. it share connections through the medial forebrain bundle, is possible that when using ratings as the response which is an important site of brain stimulation reward measure, our subjects rated males relative to other effects (olds and milner, ) and has been theorized males and females relative to other females (ariely and to be important for assessment of reward intensity (shiz- loewenstein, ). the keypress method does not suf- gal, ). vt dopamine neurons have also been inter- fer from this changing scale problem because effort is preted to respond to salient sensory events, regardless a scale that is constant across all images presented. of their relationship to reward (breiter et al., ; hor- further work is needed in order to better understand if vitz, ). the rating task results are a response language artifact arguing against a common basis for aesthetic and or a real effect. reward assessments, though, is the observation that of the two behavioral tasks, only the keypress procedure conclusion produced responses that paralleled to some degree re- this study sought to determine if social stimuli distinct sponses in reward regions such as the nac, slea, and from money, namely categories of faces segregated by vt (figures c, , and ). no reward region responded gender and attractiveness, had different reward values, in a similar fashion to the outcomes of the rating proce- and in turn induced reward circuitry activity when ob- dure. these results are consistent with predictions of served. the keypress procedure demonstrated that a the incentive salience or bindra/toates model described social stimulus that was not linked to any post experi- by berridge and colleagues (berridge, , ), ment asset or reward, had a distinct valuation that could which discusses “wanting,” but not “liking,” in terms of be objectively quantified. fmri of subjects passively meso-accumbens dopaminergic function (wyvell and viewing these faces demonstrated a significant effect berridge, ). by analysis of variance across individual subjects in the a longstanding debate in aesthetics concerns the nac, particularly in response to the beautiful female question of whether perception of beauty can be “disin- faces. by the post-hoc analysis, no one region re- terested,” or separate from desire (kant, reprinted ). sponded in a similar fashion to the rating study alone, the post-hoc analysis of our data did not show com- but a number of reward regions produced signal change pletely separated patterns of activation in reward re- with approximate similarity to the keypress data. these gions for aesthetic assessments and reward assess- results suggest that aesthetic judgement may not be ments, but instead demonstrated a set of regions that mediated by reward systems. resembled aspects of the keypress results alone. this the observations of this study build upon prior neuro- suggests that beautiful faces produce a valuation signal imaging work with multiple categories of reward stimuli (potentially involving the slea), which is processed in to argue that, at the spatial resolution of current imaging different brain regions for reward functions and aes- techniques, an extended set of deep gray matter and thetic judgements in young heterosexual male subjects. paralimbic regions serves as a generalized circuitry to given that it may be particularly difficult to dissociate process goal-related stimuli. in a previous study using rewarding from aesthetic effects with faces, future stud- monetary reward and a game of chance, our group ob- ies with non-face stimuli and nonbiological categories served this extended set of reward regions to display of goal-objects may help determine if these effects are differential activation to expectancy conditions and to the monetary gains and losses embedded in themdissociable. neuron selected from print media. each set consisted of male and (breiter et al., ). the segregation of expectancy and female faces.outcome responses demonstrated that reward/motiva- tion systems could be dissected into their constituent experimental designfunctional subsystems, but left open the issue of their behavioral tasks involvement in valuation processes. the current study rating procedure. the rating task measured the attractiveness of suggests that the same set of regions implicated in the the female and male faces for the experimental subjects. subjects processing of expectancies and outcomes, may also be viewed the faces three times each, on each occasion rating each face’s “attractiveness” on a scale of – , with representing “veryinvolved with valuation functions. a challenge for future unattractive” and representing “very attractive.” faces were orga-work is to determine the varied contributions of this nized in blocks by gender, and the order of gender was counterbal-distributed set of reward regions to the processes of anced across subjects. within each block (by gender), the beauti- expectancy, valuation, and their combination for moti- ful and average faces were always presented in a new randomly vation. generated order. studies are further warranted to address issues raised keypress procedure. the keypress task examined the reward value of average and beautiful faces. subjects were told that theyby the design and focus of the current work. for in- would be exposed to a series of pictures that if not interfered with,stance, there is the issue that differences in the gender would change every eight seconds. however, if they wanted a pic-or sexual orientation of the volunteers used for this study ture to disappear faster, they could alternate pressing the “z” and might lead to different behavioral and imaging results. “x” keys, whereas if they wanted a picture to stay longer on the the signals from reward regions in response to average screen, they could alternate pressing the “n” and “m” keys. the male faces did not resemble the results of the two be- dependent measures of interest were the amount of work in units of key press that subjects exerted in response to the different cate-havioral tasks, suggesting the need for assessing other gories of stimuli, and their resulting viewing durations.subjective dimensions. another question arises about each pair of keypresses increased or decreased the total viewingwhether the results produced by beautiful faces general- time according to the following formula: ize to those produced by bodies, or nonanimate stimuli. lastly, there is the issue of what brain regions might newtotaltime � oldtotaltime � (extremetime � process information regarding “aesthetic” beauty (i.e., oldtotaltime)/k, follow the pattern of the rating task results), as opposed to processing information regarding “desirable” beauty. where extremetime was s for keypresses reducing the viewing time, extremetime was s for keypresses increasing the viewingin pursuing these issues regarding brain function, it is time, and k was a scaling constant set to . if the elapsed timepossible we may begin to approach an understanding for the picture surpassed the total time determined by keypressing,of ruskin’s concept of the “sublime” (reprinted ) the picture was removed and the next trial began. a “slider” was with regard to the grandeur imbedded in the function displayed left of each picture indicating total viewing time at any of motivation. moment, and changing with every keypress (ariely et al., ). this procedure was controlled by authorware (macromedia). subjects were informed that the task would last min and thatexperimental procedure this length was independent of their behavior during the task, as was their overall payment of $ .subjects neuroimagingall subjects in the three experiments gave informed consent to subject instructions prior to scanning. subjects were told that theyparticipate in these procedures following the rules of the subcom- would see rapid presentations of faces intermixed with fixationmittee on human studies at the massachusetts general hospital, points, that sometimes the faces would change, and that they werethe institutional review board at the massachusetts institute of to focus on the fixation points while getting an overall sense oftechnology, and the institutional review board at harvard uni- the faces. one to two minutes prior to imaging, subjects viewed aversity. separate set of average faces with neutral expressions for imagebehavioral tasks focusing and centering.a group of eight male subjects, ages – years (mean . , sd functional imaging. subjects were scanned on an instascan de- . ), all heterosexual and right-handed by self-report, participated vice ( t general electric signa, modified by advanced nmr sys-in the rating study, and were paid $ . a separate group of fifteen tems) using a head coil, bite-bar, and standard protocol (breitermale subjects between the ages of and years (mean . , sd et al., ). this protocol included: ( ) a sagittal localizer scan . ), also all heterosexual and right-handed by self-report, partici- [conventional t -weighted spoiled gradient refocused gradientpated in the “keypress” study and were paid $ for their partici- echo (spgr) sequence; through-plane resolution � . mm; pation. slices] to orient, for subsequent scans, contiguous axial obliqueneuroimaging mm slices along the ac-pc line, ( ) an automated shimming routineten male volunteers, who had not participated in the behavioral with second order shims to optimize magnetic field homogeneitytasks, volunteered for the fmri experiment. all subjects were medi- (mean fwhm � . hz, sd . ), ( ) an spgr t -weighted flow-cally, neurologically, and psychologically normal by self-report and compensated scan (resolution � . mm � . mm � mm), ( ) aphysician-directed medical review of systems. all subjects were t -weighted echo planar inversion recovery sequence (ti � right-handed and heterosexual by self-report. fmri data collected ms, in-plane resolution � . mm), and ( ) a gradient echo, t *-from three participants had significant signal spiking, along with weighted functional sequence (tr � ms, te � ms; flip �uncorrectable motion, and could not be analyzed; data from one �; fov � � cm; in-plane resolution � . mm; participant was excluded due to noncompliance with instructions. images per slice; disdaq � ).the six remaining participants were aged – (mean . , sd . ). experimental paradigm. each experimental run included five s baseline epochs interleaved with four s face epochs (e.g., block design). to minimize attentional modulation of gaze (breiter et al.,stimuli two sets of nonfamous human faces [digitized at dpi in -bit a), face stimuli were presented in a tachistoscopic fashion for ms (face, or empty oval with a fixation point for baseline), fol-grayscale, spatially downsampled, and cropped to fit in an oval “window” sized – pixels wide by pixels high using pho- lowed by a blank screen for ms. during each run, either male or female faces were presented, with alternating epochs of averagetoshop . software (adobe systems)] classified as “beautiful” and “average” (according to pilot test results) (see figure a), were and beautiful faces. epochs of average and beautiful faces were beauty and reward counterbalanced within run, with an *a*b*b*a* or *b*a*a*b* order an overall � � . , activation clusters had to meet a corrected p value threshold (breiter et al., a, c, ) for the volume(a � average, b � beautiful, * � fixation point baseline). the gender of the faces shown and block sequence was counterbalanced of tissue ( . cc) sampled in the six a priori regions (i.e., p � . / voxels, or p � . � � ) (makris et al., ).across the eight runs administered to each subject. this resulted in each face being viewed twice. a break of approximately – min anatomic localization statistical maps of group-averaged data were superimposed overwas taken between runs. subject debriefing. after functional imaging, subjects filled out a high-resolution conventional t -weighted images that had been transformed into the talairach domain and averaged. primary ana-questionnaire about what they had seen and thought, and com- pleted the beck anxiety and depression inventories (bai: mean . , tomic localization of activation foci was based on the talairach coordinates (talairach and tournoux, ) of the maximum voxelsd . , range – out of ; bdi: mean . , sd . , range – out of ). three of the six subjects spontaneously reported noticing from each activation cluster, with secondary confirmation of this via inspection of the juxtaposition of statistical maps with structuralthat the faces differed in attractiveness. scans. localization followed the region of interest conventions de- scribed previously (breiter et al., ) for the nac, slea, amygdala, data analysis hypothalamus, vt, and gob (ba / ) (breiter et al., ), and transformation of fmri bold data before the ventral striatum proximate to the nac (drevets et al., ). all statistical mapping clusters of activation were checked against the functional image motion correction and talairach transformation. these procedures data using an objective method to ascertain that they did not overlap followed those detailed elsewhere (breiter et al., ). any areas of susceptibility artifact (breiter et al., , ). signal normalization and filtering. for all eight runs, fmri data in the talairach domain were intensity scaled on a voxel-by-voxel acknowledgments basis to a standard value of and detrended. the mean signal intensity for each voxel over all runs was removed on a time point this work was supported by grants to dr. breiter from the national by time point basis. institutes of drug abuse (grants # and # ), the office of concatenating and averaging across subjects. pairs of identical national drug control policy and counterdrug technology assess- -time point runs of talairach-transformed functional data were ment center (ondcp-ctac), and drs. breiter and aharon from the averaged within each subject (i.e., given four types of runs—female national center for responsible gaming (ncrg). dr. breiter was faces: *a*b*b*a*, female faces: *b*a*a*b*, male faces: *a*b*b*a*, also supported by the national foundation for functional brain im- male faces: *b*a*a*b*). the resulting four average runs were concat- aging. dr. etcoff was supported by the lynn m. reid fellowship of enated within each subject. these time point sequences were harvard medical school, and dr. chabris by a postdoctoral fellow- then averaged across subjects, as were individual structural images. ship from the national institutes of health through the mgh-nmr statistical mapping, roi-based analysis center. we would like to thank alex pentland and elizabeth huffman statistical mapping of general effects as rois. individual data was for their help and assistance and mark e. glickman for statistical evaluated to confirm the presence of a normal signal distribution. consultation. then, a t statistic map was created from the data averaged across subjects, using time point (n � ) as the random factor, and received june , ; revised october , .contrasting all time points during face events versus all time points during fixation point events. referenceswithin this map, clusters of activation that had maxima (i.e., mini- mum p value) in one of the six targeted reward regions were identi- fied using a cluster-growing algorithm (bush et al., ), and se- ariely, d., and loewenstein, g. ( ). the importance of duration lected as rois for analyses of variance with subject (n � ) as the in ratings of, and choices between, sequences of outcomes. j. exp. random factor (i.e., “random effects” analysis). in order to maintain psychol. , – . an overall � � . , this algorithm specifically localized activations ariely, d., breiter, h.c., and aharon, i. ( ). from mice to men: a that met a corrected p value threshold of p � . for the number continuous measurement of motivation. mit working paper . of hypothesized brain regions interrogated ( . / � . ). see arvanitogiannis, a., waraczynski, m., and shizgal, p. ( ). effects breiter et al. 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[pdf] on the truth of beauty: nietzsche, heidegger, keats | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . / - . corpus id: on the truth of beauty: nietzsche, heidegger, keats @article{sikka ontt, title={on the truth of beauty: nietzsche, heidegger, keats}, author={s. sikka}, journal={the heythrop journal}, year={ }, volume={ }, pages={ - } } s. sikka published philosophy the heythrop journal this article is concerned with the validity of what i term the “metaphysico-religious” interpretation of beauty. this term is intended to cover descriptions and interpretations of beauty which suggest that it indicates: ) a connectedness of man with nature, of natural things with one another, and/or of man with man in and through some encompassing ground or unity; and, ) the existence of another and better world, a transcendent reality in which the negative elements of factual existence are… expand view via publisher calvin.edu save to library create alert cite launch research feed share this paper citations view all one citation citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency stylistic analysis of the poem “ode to nightingale” by john keats a. b. khan, iram zehra, ghulam hafsa sociology save alert research feed references for instance , as a representation of life in thus spoke zarathustra related papers abstract citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue structural determinants of sleeping beauty transposase activity. györgy abrusán , , stephen r.yant ,* , andrás szilágyi , joseph a. marsh , lajos mátés , zsuzsanna izsvák , orsolya barabás and zoltán ivics mrc human genetics unit, institute of genetics & molecular medicine, university of edinburgh, western general hospital, crewe road, edinburgh eh xu, united kingdom institute of biochemistry, biological research center of the hungarian academy of sciences, temesvári krt. . szeged, h- , hungary department of pediatrics and genetics, stanford university school of medicine, pasteur dr., stanford, california, usa institute of enzymology, research centre for natural sciences, hungarian academy of sciences magyar tudósok krt. , h- budapest, hungary instistute of genetics, biological research center of the hungarian academy of sciences, temesvári krt. . szeged, h- , hungary max delbrück center for molecular medicine, robert rossle strasse , berlin, , germany european molecular biology laboratory, structural and computational biology unit, meyerhofstraße , heidelberg , germany division of medical biotechnology, paul ehrlich institute, paul ehrlich str. - , langen, , germany * present address: gilead sciences inc., lakeside drive, foster city, ca , usa correspondence should be addressed to g.a. or z.i.: györgy abrusán e-mail: gyorgy.abrusan@gmail.com tel.: + ( ) running title: structural determinants of sb activity mailto:gyorgy.abrusan@gmail.com abstract transposases are important tools in genome engineering, and there is considerable interest in engineering more efficient transposases. here we seek to understand the factors determining their activity using the sleeping beauty transposase. recent work suggests that protein co-evolutionary information can be used to classify groups of physically connected, co-evolving residues into elements called ‘sectors’, which have proven useful for understanding the folding, allosteric interactions, and enzymatic activity of proteins. using extensive mutagenesis data, protein modeling and analysis of folding energies, we find that ) the sleeping beauty transposase contains two sectors, which span across conserved domains, and are enriched in dna-binding residues, indicating that the dna binding and endonuclease functions of the transposase coevolve; ) sector residues are highly sensitive to mutations, with point mutations of these residues strongly reducing transposition rate; ) mutations with a strong effect on free energy of folding in the dde domain of the transposase significantly reduce transposition rate. ) mutations that influence dna and protein-protein interactions generally reduce transposition rate, although most hyperactive mutants are also located on the protein surface, including residues with protein-protein interactions. this suggests that hyperactivity results from the modification of protein interactions, rather than the stabilization of protein fold. introduction recent findings identified a structural organization of protein domains that is distinct from their known hierarchical organization into secondary and tertiary structural elements. these structures, termed ‘sectors’ form physically connected networks of coevolving residues within proteins, and span across secondary structural elements. sectors are identified from multiple alignments with a procedure called statisctical coupling analysis (sca), using the covariance matrix of amino acid variability at different positions of the alignment, and their conservation . it has been noticed that the residues that show correlated evolution in the alignments have a block structure in the sca matrix: they can be partitioned into clusters of residues, which show correlated evolution within the cluster, but are essentially uncorrelated with residues of other clusters. these groups of coevolving residues were termed ‘sectors’, in analogy to financial sectors , . several important biological properties of proteins are determined by sectors: although they typically make up only - % of the residues of a protein, they were shown to significantly contribute to the specification of protein folds , allosteric communication in proteins , and evolution of novel functions . since it is possible to engineer functional artificial protein folds based purely on sector information , or modify their functions using sector residues (at least in small domains), sectors are of considerable importance also for protein engineering. however, most work to date on the architecture of sectors, functions and importance of sectors have focused on relatively few single-domain proteins, often with only a single sector , , , , and the number of studies with multidomain and multisector proteins is low , . thus, it is unclear to what degree the current findings can be generalized, and whether sectors are of similar importance in more complex multi-domain structures as in small proteins . most dna transposons contain a single gene encoding the transposase protein, which is flanked by terminal inverted repeats (tirs). transposons ‘jump’ by a cut-and-paste mechanism, during which the transposase moves the sequence flanked by tirs to a new genomic location. since transposases require only the tirs, and any sequence flanked by tirs can be moved by externally supplied transposases, they can be used for gene transfer . as a consequence, transposons are popular tools that are widely used for genome engineering, including cancer gene identification by insertional mutagenesis , germline transgenesis , somatic gene transfer for gene therapy , or cellular reprogramming . their primary advantage over viral vectors for gene therapy is that they have considerably fewer side effects, including low immunogenicity and genotoxicity, while, at least for some applications, they provide stable transgene expression levels with efficiency matching viral vectors . several transposon systems are currently applied as genome engineering tools, including the piggybac, tol and sleeping beauty transposons – . the first dna transposon tool capable for gene transfer in vertebrates was sleeping beauty (sb), which was reconstructed from extinct tc /mariner transposons in fish . sleeping beauty, and especially its hyperactive variant is still one of the most widely used transposon tool, and it is the only transposon vector being currently in human clinical trials , . in this work, using our extensive mutagenesis data available for the sleeping beauty transposase, we investigate the structural elements that are the most sensitive to mutations, with particular emphasis on protein sectors. we show that sectors are enriched in dna-binding residues and are highly sensitive to mutations, which cannot be explained by positional conservation. in addition, our analysis suggests that hyperactivity results from the modification of protein-protein interactions, rather than improved protein folding. wild-type transposases are not optimal for practical use, because they evolved to transpose at relatively low frequency, as high transposition rates harm their host. as a consequence, modifying their activity or insertion patterns through point mutations is of considerable practical importance, and our results may aid their optimization by identifying mutations that are likely to result in transposases with reduced transposition rate. results determination of the tertiary structure of sb transposase and protein core. the amino acid sequence of the sleeping beauty transposase was obtained from ivics et al. . experimentally determined protein structures are available for the dde domain of the transposase and the n-terminal hth motif of the dna-binding domain , but not for the entire transposase. thus we predicted the tertiary structure of sleeping beauty with the i-tasser molecular modeling platform , , which uses threading and also ab-initio modeling for structure prediction. additionally, we used the coordinates of the existing experimental structures (see above) as constraints (figure s a). due to the availability of high quality templates, a high quality structure prediction was possible: the estimated template modeling (tm) score of the predicted tertiary structure with an experimentally determined structure is . (± . ). models of this quality can be successfully used in mutagenesis studies and stability analyses . the most similar structure in the protein data bank (pdb, http:/www.rcsb.org) to the predicted structure (supplementary sb.pdb file) is the mos transposase , which was also the highest ranking template used by i-tasser (see figure s b and c for structural alignments between the mos transposase and the predicted structure, and figure s for a ramachandran plot of the predicted sb transposase using procheck ). transposases typically function in a dimeric , or tetrameric enzyme complex , (and the n-terminal domain of sb was reported to be able to form tetramers in vitro ), but the high structural and mechanistic similarity of the monomer to mos strongly suggests that the active core unit of the complex is a very similar dimer as the one seen for mos . (nevertheless tetramers may exist and may even be the functional state, for example during assembly.) thus the monomer produced by i-tasser was used to build a dimer, using the mos ( hot) transposase as a template (figure s d. dna nucleotides were replaced with chimera , to match the inverted repeats of sb; next the sb transposases were superposed over the mos dimer ( hot) with tmalign , followed by correction of clashes and minimization. severe atomic overlaps (e.g. rings penetrated by other groups) in the initial complex model were manually corrected. the model was then subjected to energy minimization in vacuo by the steepest descent algorithm in gromacs using the charmm force field. the minimization converged to machine precision with no remaining overlaps between atoms. visualizations of the protein structures were made with chimera. as buried residues in proteins are known to be less tolerant of mutations than exposed residues , we determined relative solvent accessibility of each residue of the structure with dssp (see methods). the residues with relative solvent accessibility <= . were assumed to form the protein core. residues that take part in protein-protein interactions were determined using the difference in solvent accessible surface areas (sasa) of the monomeric and dimeric form of sb: all residues that have different sasa in the dimer and monomer were assumed to take part in protein-protein interactions. dna- protein interactions were determined with the snap tool of the dna package . identification of sectors of the sb transposase. to identify sectors in sb, multiple alignments were made with three different state-of-art tools: muscle , probcons and mafft (see methods). using the three alignments, statistical coupling analyses were performed to identify protein sectors, with the method described by halabi et al , using a modified matlab script provided by the same study. sca tests whether the conservation of an amino acid at any position in the sequence alignment is correlated with the conservation of any other residue of the protein , i.e. identifies residues that coevolve. first, it builds a weighted correlation matrix of coevolving amino acids for all residues in the alignment (figure a), and this matrix is subsequently cleaned from statistical noise with a randomization method . the analysis of eigenvalue spectra identified three significant eigenvalues for all three alignments (after the exclusion of the largest one), indicating that there might be up to three sectors in the protein. however, after examining residue weights along eigenvectors - we could identify only two sectors along eigenvector (see figure s ) that had similar residue compositions irrespectively of the alignment used (table s -s ). due to the different spatial pattern of the residue weights of the three alignments, attempts to identify a third sector resulted in a poorly defined sector, which had different residues depending on the alignment used, and was also strongly correlated with the other two sectors. in consequence, we use only the two sectors that could be consistently defined in all three alignments, which together contain - residues, depending on the alignment. the cleaned sca matrices of all three alignments show that the two sectors are essentially independent (figure b), i.e. the correlations between the residues of a sector are much stronger than the correlations between sectors. the location of the sectors in the transposase structure is somewhat different from the pattern observed in smaller proteins (figure e-f). residues of both sectors are located in more than one conserved domain, and in the case of the second sector, residues are present in all three pfam domains of the transposase (figure c,f), indicating that the division to conserved domains does not strictly correspond with the units of the protein that actually coevolve. sectors (but also conserved residues) are enriched in dna-binding residues: their fraction is %, as opposed to the % observed for the entire protein (p< . for all three alignments, tests of proportions), but there is no significant difference between the two sectors. the residues of sectors are physically less tightly connected than in most small proteins examined so far, which may arise from the low sequence conservation of the alignments: inaccuracies in the alignments due to the low sequence similarity result in noise, which reduces correlations among residues, and in consequence sca may fail to detect certain residues as sector residues. to a lesser degree, minor inaccuracies in the transposon sequences themselves may contribute to such noise, as many transposon sequences – including sleeping beauty – are reconstructions of extinct repeats. the dependence of transposition rate on sectors, protein core and conservation. to examine the effect of different residues and protein regions on transposition rate, we used transposition rate measurements of sb mutants, which represent a compilation of all sleeping beauty point mutations known to us and also unpublished mutants (see methods). the distribution of point mutations is approximately uniform across the sb transposase sequence (figure a); however their amino acid distribution is not as the majority of mutants were alanine replacements (figure s ). in general, the transposition rates of mutants vary significantly, from completely inactivating the transpsosase to significantly increasing the transposition rate (figure a). the location of the residues in the protein structure have a large influence on their effect: mutations in protein sectors, conserved residues (d > . , see methods) and the protein core result in a significantly larger reduction in transposition rate in comparison with the residues that do not belong to any of these groups (figure b, both sectors, conserved residues and the core are significantly different from other residues, p << . , pairwise comparisons with mann-whitney u tests). sectors represent an extension of the traditional concept of conservation, and there is significant overlap between residues that are part of a sector and also have high positional conservation (d > . ). recently it has been questioned whether the effect of sectors on transposition rate is independent from the effect of conservation . to test this, we split sector and conserved residues into three groups: sector residues with low conservation (d < . ), sector residues with high conservation, and conserved residues that are not part of a sector. the comparison of these groups with residues that are neither part of sectors, nor the protein core, and are also not conserved (“other” residues, figure ) indicates, that the effect of sectors on transposition rate is not simply due to positional conservation, as the three groups are significantly different from the “other” residues (p < . for all comparisons except “conserved only” of the mafft alignment, fisher post–hoc tests, anova on log transformed transposition rates). there is no significant difference between non-conserved sector and non-sector conserved residues (p > . in all three alignments, fisher post–hoc tests, anova). the effect of mutations on protein stability. most proteins can function only in a narrow range of folding energies , as unstable proteins may not fold properly and very stable ones may be too rigid to perform their functions. mutating a residue in a protein can have significant effects on its overall stability (Δg, the free energy of unfolding) and function, thus we tested whether the differences in transposition rate between the sectors, conserved residues and core of the protein and other residues are caused by their effect on protein stability, measured as the difference of the predicted folding energy (ΔΔg) between the wild type sb transposase and the mutants. the analysis shows that mutations in sector, conserved and core residues usually have a destabilizing effect on the structure (ΔΔg > , p << . , t-tests; figure a). although three conserved domains were identified in the sb sequence, an analysis of the flexibility of the structure with the pisqrd tool and also recent analyses of the mos and sb transposase , indicate that the structure can be split into two large regions; the relatively flexible n- terminal part of the protein containing the dna binding hth-domains (residues - ), and a rigid, globular region (residues - ) containing the dde domain (figure b, figure c). mutations have different effects on folding energies in these two regions; while we detected a clear negative correlation (p << . , r = - . ) between transposition rate and ΔΔg (figure c) in the globular part of the protein, there is no such relationship (p = . , r= . ) in the n-terminal region containing the hth domains (figure d). next we tested whether mutants in the two regions have different effects on the transposition rate of sb, and we found that the two regions are markedly different. in the flexible part of the protein mutants of sector, conserved and core residues do not differ significantly from the remaining residues (p> . for all comparisons, mann-whitney u tests, figure a), while in the region containing the dde domain there is a highly significant difference (p << . for all comparisons, mann-whitney u tests, figure b). additionally, % of the mutants of “other” residues have higher transposition rates than the wild type. as the location of mutations has a significant effect on the free energy of folding, and in the dde domain g is correlated with transposition rates (figure d), we tested whether the effect of sectors remains significant if we remove the effect of ΔΔg on transposition rate, i.e. we adjust all rates to ΔΔg = . the results show that the corrected transposition rates are still highly significantly different from other residues (p < . for all comparisons, mann-whitney u tests, figure c), thus the biological effect of sectors and conserved residues cannot be explained with their effect on ΔΔg alone. the effect of protein-protein and protein-dna interactions on transposition rate. transposases typically form protein complexes during transposition, and recent studies on mariner transposases related to sleeping beauty (hsmar and mos ) indicate that mutants that disrupt allosteric communication within its dimer are characterized by increased activity – . in particular, almost all mutants of the conserved wvphel motif (except p and e) of hsmar transposon were hyperactive , most likely due to lowering the kinetic barrier to synapsis , . our findings suggest that the mechanism that causes hyperactivity in sb may be comparable to hsmar ,and probably involves the modification (or disruption) of protein– protein interactions (although the wvphel motif is not conserved in the sb transposase). this hypothesis is also consistent with the observation that the relationship between transposase concentration and sb activity is similar to hsmar . we tested whether mutants of residues taking part in protein-protein and dna-protein interactions have different transposition rates than other residues at the protein surface. in general, when outliers are excluded, mutants of both protein and dna-interacting residues have significantly lower transposition rates than other residues at the surface (figure , p < . , kruskal-wallis test). however, all but two of the hyperactive mutants (with % or higher activity) are located at the protein surface, and none are present in the core of the dde domain. of the hyperactive surface mutations, four are in the protein-protein interfaces of the dimer (including the most active mutant), and none are in dna-protein interfaces (see figure and supplementary chimera visualization). since the sb transposase can probably also form tetramers during transposition , there are probably more residues that take part in protein-protein interactions, suggesting that modification of interactions might be a key factor responsible for hyperactivity. discussion we performed an analysis of protein sectors in a relatively large, multidomain protein with a complex tertiary and quaternary structure, and attempt to predict the effect of mutations on transposition rate, based on their location and effect on protein stability. although sector identification depends on the alignment used, we could identify two sectors in the sb transposase, regardless of the alignment method. most previous studies focused on smaller, single-domain proteins , , , and one study identified a sector that spans two domains; our analysis indicates that sectors can span multiple conserved domains of a protein (figure e-f), and, in the case of sb, are enriched in dna binding residues. there may be at least two explanations for the observation that sectors residues are present in more than one domain: first, in some stages of transposition these residues may be in physical contact. second, since sector identification is a purely statistical procedure which searches for coevolving residues in the entire protein sequence, in the case of two (or multi) domain proteins where both domains are necessary for the protein to function, coevolution between the domains is highly likely (and sectors that are confined to a single domain are probably present only in domains that are essentially independent). a significant effect of mutations on transposition rate could be demonstrated in sectors, the protein core, conserved residues, protein-protein and protein-dna interface: mutating these residues typically resulted in transposases with low transposition rates. recently teşileanu et al. suggested that depending on the method used for sector identification, any biological effect of the first sector may be the consequence of sequence conservation alone . since we used the method of halabi et al. for sector identification, which does not use the first eigenvector of the sca correlation matrix, their concerns do not apply for our results. however, as a significant fraction of sector residues are conserved, we also analyzed sector and conserved residues independently, which shows that mutations of not conserved sector residues have a similar effect on transposition rate as mutations of conserved but non-sector residues (figure ), thus the biological functions of sectors cannot be explained with conservation alone. in comparison with smaller proteins , the influence of sectors on protein function appears to be more complicated, and depend on the tertiary structure. in the globular part of the protein, we could detect a clear effect of sectors, conservation and core on transposition rate, even when the effect of the free energy of folding was excluded (figures ). however, in the flexible part of the protein containing the hth-domains we found no effect of sectors, nor a correlation between transposition rate and g (figure ), which indicates that further studies are needed to evaluate the importance of sectors in non-globular (including disordered and coiled coil) proteins. while we didn’t find a “recipe” for making hyperactive mutants of sb, our analysis allows prioritizing residues for targeted mutagenesis. half of the residues in the dde domain that are not part of sectors, conserved residues or protein core have increased transpositional activity. in addition, out of the hyperactive mutants (mutants with at least x increased activity compared to the wild type) are located in the protein surface, and of them are in the protein-protein interfaces of the dimer, suggesting that similarly to the hsmar , the disruption of self-regulating protein-protein interactions may be an important factor in generating hyperactive mutants. in contrast, no hyperactive mutants are present in dna-protein interfaces or in the buried residues (core) of the dde domain. since mutations of these regions typically strongly reduce the rate of transposition, this suggests that despite the fact that sb is a reconstructed sequence and it is most likely inaccurate to some degree, both dna binding and folding are close to optimal. materials and methods identification of sb homologs and making of multiple alignments. transposase sequences homologous to sleeping beauty were identified in the -frame translated repbase database (v . ) , the main database of eukaryotic transposable elements, using the jackhmmer tool of the hmmer . package , with bit score cutoff . we excluded from the hits all matches that show homology only to a short fragment of sb, and kept only those hits that span at least from residues to of the sb transposase, thus covering more than % of the sequence. next, to remove sequences with high similarity (> %), the homologous sequences were clustered with uclust . the determination of protein sectors depends on multiple sequence alignments, but in the case of sb the average pairwise sequence similarity between the homologous sequences is low ( %), and in this low range of sequence similarity only approximately - % of the residues can be aligned correctly with current methods . this means that the choice of the aligner may influence the results significantly (i.e. the determination of sector and conserved residues), and to estimate the biases introduced by different alignment methods, we used three different alignment tools: muscle , probcons and mafft . after aligning the sequences, the alignments were trimmed to the residues of sb transposase, i.e. we removed all columns with gaps in the sb sequence. all three alignments are available for download as supplementary data. determination of conservation and sca calculations. conservation (d, kullback-leibler entropy) at any given position of the sequence was defined as the divergence of the observed frequency from the background frequency of the most frequent residue at the position, and was calculated with the following equation: d = f ln(f/q) + ( –f) ln[( -f)/( -q)] , where f denotes the frequency of the amino acid at a given position of the sequence, and q represents its background frequency. we used the same background frequencies as in , and conserved residues were defined as residues with d > . . both for sca and d calculations, we excluded all positions from the alignments, where the frequency of gaps was higher than %. sca calculations (calculating the correlation matrix, spectral cleaning, randomization of the alignments) were performed with a modified matlab script provided by the halabi et al. . sectors were determined by a visual examination of residue weights of eigenvectors - (see halabi et al. for details), sector was defined as residues with weights < - . along eigenvector , sector as residues with weights > . along eigenvector (see figure s ). construction of sb mutants and determining their transposition rate. the mutants were partly obtained from published studies , – , and partly (~ mutants) represent unpublished material. site- directed mutagenesis of the transposase gene was done by pcr following the quikchange (stratagene) principle of site-directed mutagenesis. the mutants were tested against the corresponding wild-type sb transposase in cell-based transposition assays, as originally described by ivics et al. . stability calculations and in-silico mutagenesis. the free energy of unfolding (Δg) of the sb transposase, its changes, and its components (e.g. van der waals forces, solvation energies, hydrogen bonding) were calculated with the foldx tool (version ) , , using the predicted structure of the sb complex. first, the structure produced by i-tasser was optimized with the repairpdb function to correct torsion angles, van der waals clashes and total energies. next we calculated the effect of the mutations on the Δg of the structure for the mutants. the difference in Δg (and its components) between the ‘wild type’ sb and its mutants is given as ΔΔg; its positive values indicate destabilizing, negative values stabilizing mutations. acknowledgments we thank mark a. kay for support, and the referees for useful comments and suggestions. györgy abrusán was supported by the hungarian scientific research fund (otka grant pd ) and the medical research council (grant mr/m x/ to j.m.). andrás szilágyi was supported by the otka grant k . zoltán ivics was supported by the european union (eu fp jumpy and eu fp inther grants), and also by grants from the volkswagen stiftung and the bundesministerium für bildung und forschung (ngfn- ). zsuzsanna izsvák was supported by the eu fp inther grant. joseph a. marsh was supported by the medical research council (mr/m x/ ). orsolya barabás was supported by the embl. supplementary material supplementary material is available in the online version of the paper: supplementary figures - ; supplementary tables - ; the predicted structure of the sleeping beauty transposase (sb.pdb); chimera visualizations of the transposase dimer showing the hyperactive ( +% activity) mutants (hyperactive.py) and the mutants marked as “other” (other.py); and the alignments used to determine protein sectors. a list with sb mutants is available in the attached mutations.txt file, the remaining mutants are available from wang y., nagy e.e, pryputniewicz-dobrinska d. et al.: regulated complex assembly safeguards the fidelity of sleeping beauty transposition (submitted). references . halabi, n, rivoire, o, leibler, s and ranganathan, r ( ). protein sectors: evolutionary units of three-dimensional structure. cell : – . . teşileanu, t, colwell, lj and leibler, s ( ). protein sectors: statistical coupling analysis versus conservation. plos comput. biol. : e . . socolich, m, lockless, sw, russ, wp, lee, h, gardner, kh and ranganathan, r ( ). evolutionary information for specifying a protein fold. nature : – . . süel, gm, lockless, sw, wall, ma and ranganathan, r ( ). evolutionarily conserved networks of residues mediate allosteric communication in proteins. nat. struct. 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two hth domains with dna binding functions, and a dde domain with endonuclease activity. d) the distribution of conservation scores (d) across the sequence. e-f) the location of the two sectors identified with the muscle alignment in the tertiary structure of the sb transposase. the sectors are located across secondary structure elements, and are less compact than the ones reported so far, possibly due to the low sequence similarity in the alignments. both sectors have residues in multiple conserved domains, most notably in sector , which have residues in all three pfam domains of the protein. g) the location of the conserved residues (d > . , muscle alignment) of the transposase. h) the residues of the protein core. all residues with relative solvent accessibility below . are highlighted with red. figure . effect of residue location on the transposition rate of sb mutants. a) the location of the mutations along the sb transposase sequence, and their effect on transposition rate. the mutants are distributed approximately evenly across the sequence; the majority of mutants reduces transposition rate (< % of sb). none of the pfam conserved domains show a clear difference from the rest of the sequence. b) the effect of sectors, conserved residues and protein core on transposition rate (median, box: %- %, whiskers: %- %). mutants in both sectors, conserved residues and residues of the protein core have significantly lower transposition rates than other residues, irrespectively of the aligner used (p < . , mann-whitney u tests). figure . the effect of sectors on transposition rate is not a by-product of positional conservation. sector and conserved residues were split into three groups: sector residues with low positional conservation (d< . ), sector residues with high positional conservation, and conserved residues that are not part of any sector. transposition rates of mutants (median, box: %- %, whiskers: %- %) in all three groups are significantly different from mutants in other residues (p << . for all comparisons, fisher post–hoc tests, anova on log transformed transposition rates), and there is no significant difference between the mutants of non-conserved sector and conserved but non-sector residues (p > . in all three alignments, fisher post–hoc tests). figure . the effect of mutations on the change of the free energy of unfolding (median, box: %- %, whiskers: %- %). a) mutations in sectors and the core are significantly more destabilizing (ΔΔg > ) than mutants of other residues (p < . for all comparisons, t-tests). b) the flexible n-terminal arm of the protein containing the hth domains (residues - ) is indicated with white, the globular part (residues - ), which contains the dde domain, with gray. c) in the flexible arm the effect of mutations on ΔΔg is not correlated with transposition rate (p = . ). d) in the globular region we find a significant negative correlation (p << . , r = - . ) between ΔΔg and transposition rate. figure . the effect of residue location on transposition rate, in the two regions of the protein (median, box: %- %, whiskers: %- %). a) in the hth-region, mutants of sectors, conserved or buried residues are not significantly different from the remaining mutants (p > . for all comparisons, mann-whitney u tests). b) in the dde domain the differences are highly significant (p < . for all comparisons, mann-whitney u tests), even after correcting for the different effects of free energy of folding (c). note that in the dde domain % of mutants of “other” residues are characterized with higher activity than the wild type sb. figure . the effect of dna-protein and protein-protein interactions on transposition rate. when outliers are excluded, mutants of residues interacting with dna (“dna”) and the other sb chain (“ppi”) have significantly lower transposition rates (p< . , mann-whitney u test) than other residues located at the surface (rsa > . ). surprisingly, of the hyperactive mutants (outliers, +% activity) are also located in the protein surface, and none in the dna binding regions, suggesting that the modification of protein-protein interactions might be responsible for their dramatically increased activity. (outliers with identical transposition rates were shifted by %, for visibility) figure . the location of the hyperactive mutations in the sb dimer. yellow residues represent mutants in protein-protein interfaces, red residues other mutants. as sb probably forms also a tetramer in certain phases of transposition, the number of residues taking part in ppis is probably higher. (see also the supplementary “hyperactive.py” chimera file.) m us cl e pr ob co ns m af ft f e dc b g a sector sector conserved d residues h core b a position in sb sequence (aa) t ra ns ps os iti on r at e of m ut an ts ( % o f s b ) sector sector conserved core other t ra ns po si tio n ra te o f m ut an ts ( % o f s b ) muscle probcons mafft sectors only sectors+conserved conserved only other t ra ns po si tio n ra te o f m ut an ts ( % o f s b ) muscle probcons mafft a b c d - - ∆∆g (kcal /mol), hth domains - . . . . . . . . . lo g tr an sp os iti on r at e ( = % s b ) r = . p = . - - - ΔΔg (kcal/mol), dde domain - . . . . . . . . . lo g tr an sp os iti on r at e ( = % s b ) r = - . p = . y = . - . *x hth domains “dde domain” sector sector conserved core other - ∆ ∆ g ( kc al /m ol ) muscle probcons mafft a c b sectors conserved core other t ra ns po si tio n ra te o f m ut an ts ( % o f s b ), h t h d om ai ns muscle probcons mafft sector sector conserved core other t ra ns po si tio n ra te o f m ut an ts ( % o f s b ), d d e d om ai n muscle probcons mafft sector sector conserved core other c or re ct ed tr an sp os iti on r at e of m ut an ts (% o f s b ), d d e d om ai n muscle probcons mafft dna ppi other t ra ns po si tio n ra te ( % o f s b ) median %- % non-outliers outliers copyright © the korean society of plastic and reconstructive surgeons this is an open access article distributed under the terms of the creative commons attribution non-commercial license (http://creativecommons.org/ licenses/by-nc/ . /) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. www.e-aps.org o ri gi na l a rt ic le introduction it is well-known that the main goals of doctor-patient communi- cation are creating a good interpersonal relationship, facilitating exchange of information, and including patients in appropriate decision making [ ]. this is especially important for doctors specializing in the field of aesthetic plastic surgery or perform- ing these procedures. because beauty perceptions and standards contemporary koreans’ perceptions of facial beauty seung chul rhee , soo-jung an , rahil hwang teuim aesthetic plastic surgery clinic & damsoyu hospital, seoul; medical affairs, hugel inc., seoul; department of community nursing , shinhan university, uijeongbu, korea background this article aims to investigate current perceptions of beauty of the general public and physicians without a specialization in plastic surgery performing aesthetic procedures. methods a cross-sectional and interviewing questionnaire was administered to people in seoul, south korea in september . the questionnaire addressed three issues: general attitudes about plastic surgery (q ), perception of and preferences regarding korean female celebrities’ facial attractiveness (q ), and the relative influence of each facial aesthetic subunit on overall facial attractiveness. the survey’s results were gathered by a professional research agency and classified according to a respondent’s gender, age, and job type ( % ± . % confidence interval). statistical analysis was performed using spss ver. . , calculating one-way analysis of variance with post hoc analysis and tukey’s t-test. results among the respondents, . % were in favor of aesthetic plastic surgery. the most common source of plastic surgery information was the internet ( . %). the most powerful factor influencing hospital or clinic selection was the postoperative surgical results of acquaintances ( . %). we created a composite face of an attractive korean female, representing the current facial configuration considered appealing to the koreans. beauty perceptions differed to some degree based on gender and generational differences. we found that there were certain differences in beauty perceptions between general physicians who perform aesthetic procedures and the general public. conclusions our study results provide aesthetic plastic surgeons with detailed information about contemporary korean people’s attitudes toward and perceptions of plastic surgery and the specific characteristics of female korean faces currently considered attractive, plus trends in these perceptions, which should inform plastic surgeons within their specialized fields. keywords beauty / face / perception / korean / plastic surgery correspondence: seung chul rhee teuim aesthetic plastic surgery clinic, changrim bldg f, gangnam- daero, gangnam-gu, seoul , korea tel: + - - - fax: + - - - e-mail: artprs@naver.com seung chul rhee, md, phd is an advisory board member of hugel inc. no funding has been provided for this article. otherwise, all of the authors have no financial interest or conflict of interest in any of the data, products, and/or devices mentioned in this article. the contents of this article were presented at the hugel expert leaders forum (h.e.l.f) on september , in seoul, korea. received: jan • revised: jun • accepted: jun pissn: - • eissn: - • https://doi.org/ . /aps. . . . • arch plast surg ; : - http://crossmark.crossref.org/dialog/?doi= . /aps. . . . &domain=pdf&date_stamp= - - vol. / no. / september continuously change over time and from one generation to the next, aesthetic plastic surgeons must discern people’s percep- tions of beauty and interpret contemporary trends in aesthetic preferences, enabling us to better meet the expectations of the general public. in clinical practice, it is often observed that tradi- tional beauty standards or data regarding ideal facial configura- tions does not correspond with the actual desires of the general public. in addition, sometimes there are discrepancies in beauty standards and preferences between aesthetic plastic surgeons and the general public. furthermore, we as board certified plas- tic surgeons do not have information on how general physicians feel about facial beauty. notions of facial attractiveness have been influenced by developments in society which potentially play a role in influencing the perception of attractiveness [ ]. this article aimed to describe the contemporary perceptions of korean people based on a cross-sectional questionnaire study and investigated whether any noticeable difference in beauty perceptions exists between general physicians interested in aes- thetic plastic surgery procedures and ordinary citizens. this ar- ticle will help board-certified plastic surgeons understand the contemporary aesthetic desires of the general public and the concepts of beauty of general physicians. methods study and questionnaire design we distributed a self-administered questionnaire using purpo- sive sampling to identify the range of perceptions of beauty among people in seoul, south korea. the questionnaire was designed and detailed feedback was obtained from piloting the questionnaire with several clerks at hugel, inc. a final revision of the questionnaire was completed based on the pilot data be- fore use. participants and data collection study participants were invited to take part in this questionnaire by research specialist clerks from panel marketing interactive, co. ltd, seoul, korea (pmi). doctors who participated in the hugel expert leaders forum in also filled out this ques- tionnaire. in addition, clerks from hugel, inc. randomly distrib- uted the questionnaire to general physicians interested in aes- thetic plastic surgery and procedures, patients seeking aesthetic surgery and procedures, and ordinary citizens residing in seoul. the questionnaires were collected from those who voluntarily completed them. during the survey, informed consent was indi- vidually obtain for participants of this study about the purpose of this study, the manner and form in which data will be collect- ed, confidential or privacy issues from hegel inc. there were no other eligibility criteria for participation, but board-certified dermatologists and board-certified plastic surgeons were ex- cluded from this study. identical questionnaires on beauty per- ceptions were distributed to all respondents. survey characteristics participants were asked to record their age group, gender, and job characteristics. age groups were subdivided into groups (‘ d’, less than years old; ‘ d’, age from to ; ‘ d’, age from to ; and ‘ d’, years and older). the job char- acteristics were classified into groups according to the inter- national standard classification of occupations (isco- ) and the korean standard classification of occupations (ksco) [ ]. the structured questionnaire and interview investigation was performed in seoul, south korea. the questionnaires con- sisted of various questions about beauty perceptions and cogni- tion. as shown in table , we categorized and subdivided the questionnaire into three categories. first, we asked respondents about their general attitude regarding plastic surgery and how they make their decisions on plastic surgery. second, to identify people’s concrete perceptions of facial attractiveness, we asked respondents to nominate named celebrities, based on their beauty perceptions of who was attractive. thirty-nine famous korean female celebrities’ facial photographs were cropped to the same size. the korean celebrities’ names are listed in the footnotes of table . respondents were asked to rate the facial attractiveness of each celebrity on a scale of – . respon- dents were instructed to give a score of to the celebrity they considered to have the most beautiful face and to rate the rest of the samples relatively (a face with an assigned score of was considered to have average attractiveness). we also asked respondents to choose a representative celebri- ty that they deemed most beautiful or attractive. then, since we wanted to assess the concrete shape or configuration of each at- tractive facial aesthetic subunit, we requested that all parts of q , which asked about each subunit, be answered. third, we wanted to investigate the relative importance or influence of each facial aesthetic subunit (e.g., eye shape, nose shape, or chin shape) on overall perceived facial attractiveness. the questions regarded the degree of influence each aesthetic subunit has on overall facial attractiveness. respondents were instructed to an- swer all questions by rating how much they felt a particular facial feature/characteristic influenced overall attractiveness. respon- dents answered on a likert scale of – where was “never important” and was “very important.” the facial features/ characteristics that were included in the questionnaire were: skin condition, eyes, nose, lips, cheekbones, lower jaw, harmony and balance of facial features (i.e., eyes, nose, and lips), facial ex- rhee sc et al. prototype of an attractive korean face pression, facial volume, and degree of youthfulness (as a trend- ing word of korean language, “dhong-ahn,” which means child- like appearance). data analysis the questionnaire’s results were gathered by pmi, a research agency, in september . the statistics have a % confi- dence level with an error of ± . %. the data was collected and a general statistical analysis was performed by pmi. addi- tional statistical analysis and verification was performed by one of the authors of the article. statistical analysis was performed to assess the difference in the attractiveness evaluation scores based on respondents’ gender, age group, and job characteris- tics. the respondents’ jobs were categorized into two main groups: doctors and the public. one-way analysis of variance with post hoc analysis and tukey’s t-test using spss ver. . (spss inc. chicago, il, usa) were performed to evaluate group differences. results a total of questionnaires were completed and analyzed. among the respondents ( males and females, one person did not identify their gender), there were members of the general public ( . %) and doctors ( . %; among doctors, . % had a board certification other than dermatology or plastic surgery and . % were general physicians). nineteen people did not report their job characteristics. the general de- mographic characteristics have been summarized in table . the survey was categorized and conducted to assess three study objectives and results have been summarized in the tables. the three study objectives are as follows: ( ) general attitude about plastic surgery (table ), ( ) people’s preferences regarding fa- cial aesthetic subunits among korean female celebrities, and ( ) the individual power or relative influence each facial aesthetic subunit has on the perception of overall beauty or attractiveness as perceived by the general public (table ). q : general attitudes about plastic surgery (table ) as described in table , . % of respondents were in favor of aesthetic plastic surgical procedures and the percentage of peo- ple against plastic surgery was only . %. as detailed in fig. , among all respondents, . % responded that they were in favor of aesthetic plastic surgery, . % were neutral, and . % op- posed. fig. also shows us that there was no statistical differ- ence in the attitude about plastic surgery between genders. regarding sources of plastic surgery information, most people obtain information about aesthetic plastic surgery or procedures from mass media such as the internet ( . %), tv broadcasting ( . %), and newspapers or magazines ( . %), indicating that . % of respondents report mass media as their main source of information. . % of people obtain information from acquain- question response method q : general attitude about plastic surgery are you in favor of or against plastic surgery? likert how do you get information about aesthetic plastic surgery? please select the most important one among internet, acquaintances or relatives, books or magazines, tv broadcasting, surgical results of other people, and other sources. select one which information do you regard as usually correct among the above information sources? if you are going to undergo aesthetic plastic surgery, what are the three most important factors to consider? please check them in order of importance: postoperative surgical results, recommendations from acquaintances, fame of a surgeon, consultation with a doctor, fees for an operation, size and scale of a clinic, existence of doctors’ medical accidents or malpractice, clinic’s service convenience, distance to the clinic, guardian’s recommendation and decision, and other factors. q : peoples’ preferences on every facial aesthetic subunit for korean female celebrities please choose only one celebrity among the famous female celebrities presented. if there is another celebrity you prefer, please write in her name. select one people were then asked to answer the following questions: who has the most attractive face? who has the most attractive eyes? who has the most attractive nose? who has the most attractive lips? who has the most attractive cheeks? who has the most attractive facial volume? who has a beautiful skin condition? whose eyes are the most attractive? whose chin is the most attractive? whose face has a v-shaped jaw? who is the most beautiful woman that has a traditional korean face? who has the most westernized face? who do you think that most chinese people like? who do you think that most white people like? q : the individual aesthetic influence of each facial subunit perceived by the general public the respondents reply on the relative importance of skin condition; eyes; nose; lips; malar shape; shape of the jaw; harmony among the eyes, nose, and lips; facial expression; facial volume; and youthful appearance on overall facial attractiveness. likert likert: a set of bipolar adjective pairs (using a -point likert response scale with semantic differential), korean female celebrities comprise the following: gain, nam-joo kim, min-jung kim, so-hyun kim, tae-hee kim, hye-soo kim, hee-sun kim, hee-ae kim, nana, se-bin myung, geun-young moon, chae-won moon, bo-young park, han-byul park, sulli, seol-hyun kim, yu-ri sung, yaejin son, hye-gyo song, suji, en-ha shim, yuri, yui, in-na yoo, jin yoo, som lee, young-ae lee, jaekyung, in-hwa jeon, ji-hyun jeon, jessica, yeo-jung jo, ji-woo choi, crystal, taeyeon, yeon-soo ha, ga-in han, hyeri, shin-he hwang. table . questionnaire vol. / no. / september tances or their relatives. concerning the trustworthiness of in- formation sources, people regarded postoperative surgical re- sults of other people ( . %) as the most valuable information. recommendations from acquaintances or relatives ( . %) were somewhat important also. people regarded, in descending order, mass media such as tv broadcasting ( . %), the inter- net ( . %), and newspapers or magazines ( . %) as not being trustworthy information sources. the three most powerful fac- tors influencing respondents’ final decisions on hospital or clinic selection were postoperative surgical results of acquaintances ( . %), existence of doctors’ medical accidents or malpractice ( . %), and the fame of the doctor ( . %). these were fol- lowed by relatively minor factors including cost of the procedure ( . %), consultation with a doctor ( . %), recommendation from acquaintances ( . %), size and scale of the clinic ( . %), quality of service ( . %), and distance to the clinic or hospital ( . %). q : people’s preferences on facial aesthetic subunits among korean female celebrities of the photographic samples of korean celebrities, the celebrities with the highest attractiveness scores, in descending order, were tae-hee kim ( . %), ji-hyun jun ( . %), hye- kyo song ( . %), ga-in han ( . %), chae-won moon ( . %), young-ae lee ( . %), hee-sun kim ( . %), yaejin son ( . %), suzy bae ( . %), and hye-soo kim ( . %). respondents were requested to select only one celebrity whom category no. (%) (n = ) sex male ( . ) female ( . ) not stated ( . ) age range (yr) – ( . ) – ( . ) – ( . ) – ( . ) ≥ ( . ) not stated ( . ) job doctors ( . ) total other board-certified doctorsa) ( . ) general physicians ( . ) general public ( . ) specialized job ( . ) service or sales work ( . ) clerical work ( . ) technical post ( . ) physical labor ( . ) other types of work ( . ) not stated ( . ) general demographic characteristics inform us that the number of female respondents ( . %) was larger than that of males ( . %). regarding age groups, . % of respondents were less than years old: and under ( . %), – years old ( . %), – years old ( . %), and and above ( . %). regarding job characteristics, . % of responders were not doctors, and . % were doctors working in the aesthetic plastic surgery field. in descending order, respondents consisted of doctors ( . %), service or sales workers ( . %), manual laborers ( . %), and others ( . %). a)this refers to doctors with a specialization other than plastic surgery. table . respondents’ demographic characteristics questionnaire no. (%) are you in favor of or against plastic surgery? in favor ( . ) neutral ( . ) opposed ( . ) depends on the circumstances ( . ) not sure ( . ) non-respondents ( . ) the way of obtaining information about aesthetic plastic surgery internet ( . ) relatives or acquaintances ( . ) tv broadcasting ( . ) newspapers or magazines ( . ) other sources ( . ) non-respondents ( . ) trustworthiness of information surgical results of other people ( . ) recommendation from acquaintance or relative ( . ) tv broadcasting ( . ) internet ( . ) newspapers or magazines ( . ) other sources ( . ) selection criteria for clinic choice postoperative surgical outcomes of relatives or acquaintances ( . ) existence of doctors’ medical accidents or malpractice ( . ) fame of the doctor ( . ) charges or cost ( . ) consultation with the doctor ( . ) recommendation from acquaintance ( . ) size and scale of the clinic ( . ) clinic’s convenient service ( . ) distance to the clinic ( . ) other criteria ( . ) when we investigated perceptions about aesthetic plastic surgery procedures, more people ( . %) were in favor of aesthetic plastic surgical procedures than against ( . %). most people obtained information from the internet ( . %), acquaintances or relatives ( . %), and tv broadcasting ( . %) in descending order. regarding the trustworthiness of information sources, the largest proportion of people regarded the postoperative surgical results of their acquaintances and relatives ( . %) to be trustworthy, followed by recommendations from acquaintances ( . %), and tv broadcasting ( . %) in descending order. in terms of clinic selection criteria, the three most influential factors were the postoperative surgical results of people’s acquaintances and relatives ( . %), existence of doctors’ medical accidents or malpractice ( . %), and the fame of a surgeon ( . %). table . q : general attitude about plastic surgery rhee sc et al. prototype of an attractive korean face they felt had the most beautiful facial components or individual aesthetic subunits such as facial shape, eyes, nose, lips, cheek- bones, and so on, as listed in q in table . the comprehensive questionnaire results regarding the celebrities and their most preferred facial components have not been included in this arti- cle. the top four celebrities or those supported by at least a fifth of the respondents are mentioned. the top four celebrities ranked as having the most beautiful facial shape are tae-hee kim ( . %), ji-hyun jun ( . %), hye-kyo song ( . %), and chae-won moon ( . %). the celebrities considered to have the most beautiful nose, in descending order, are ga-in han ( . %), tae-hee kim ( . %), chae-won moon ( . %), and ji-hyun jun ( . %). hye-kyo song ( . %) and ji-hyun jun ( . %) were regarded as having the most attractive lips. people regarded chae-won moon ( . %) and tae-hee kim ( . %) as having the most beautiful cheekbones. in terms of facial vol- ume, chae-won moon ( . %), tae-hee kim ( . %), and hye-kyo song ( . %) were regarded as having the most attrac- tive facial volume. people chose ji-hyun jun ( . %), sulli ( . %), and nam-joo kim ( . %) as celebrities representa- tive of the so-called v-line lower face. young-ae lee ( . %) and in-hwa jeon ( . %) were considered to embody tradition- al korean beauty the most. however, respondents regarded nana ( . %), shin-hye hwang ( . %), and ga-in han ( . %) as women exemplifying western beauty and respond- ed that nana ( . %), gain ( . %), and ji-hyun jun ( . %) variable (mean ± standard deviation) sex age group job male female d d d d p d skin condition ( . ± . ) mean . . . (a,b)* . (a) . (a,b,c) . (c) . . t or f (p) – . ( . )* . ( . )* – . ( . )* eyes ( . ± . ) mean . . . . . . . . t or f (p) . ( . ) . ( . ) – . ( . ) nose ( . ± . ) mean . . . . . . . . t or f (p) . ( . ) . ( . ) . ( . )* lips ( . ± . ) mean . . . . . . . . t or f (p) . ( . ) . ( . ) . ( . ) cheekbones ( . ± . ) mean . . . . . . . . t or f (p) – . ( . ) . ( . ) . ( . ) lower jaw ( . ± . ) mean . . . . . . . . t or f (p) – . ( . ) . ( . ) – . ( . ) harmony ( . ± . ) mean . . . . . . . . t or f (p) . ( . )* . ( . ) – . ( . ) facial expression ( . ± . ) mean . . . . . . . . t or f (p) . ( . ) . ( . ) – . ( . ) facial volume ( . ± . ) mean . . . . . . . . t or f (p) – . ( . ) . ( . ) . ( . ) youthfulness ( . ± . ) mean . . . (a,b)* . (b) . (a,b) . (a) . . t or f (p) . ( . )* . ( . )* . ( . ) the facial features with the greatest contribution to overall facial attractiveness were harmony of facial features, skin condition, and facial expression, with the mean scores being . ± . , . ± . , and . ± . , respectively. in descending order, males evaluated harmony of facial features ( . ), skin condition ( . ), and facial expression ( . ), while females considered skin condition ( . ), harmony of facial features ( . ), and facial expression ( . ) as facial features/characteristics that have the greatest contribution to overall facial attractiveness or beauty. in terms of job type, there were differences in the responses as well. the public rated harmony of features ( . ) and skin condition ( . ) as the two most important features, followed by facial expression ( . ) and eyes ( . ). doctors ranked harmony of facial features ( . ), skin condition ( . ), and eyes ( . ) as features that have the highest degree of influence on overall facial attractiveness or beauty. d, and under; d, respondents aged – ; d, respondents aged – ; d, years old and above; p, general public; d, doctors. *statistically significant variables, p < . . table . q : statistical analysis for the degree of influence particular facial features have on overall facial attractiveness or beauty vol. / no. / september would be considered the most beautiful korean celebrities from a western point of view. when respondents were requested to provide names of additional celebrities that they would like to add to the sample list of attractive korean celebrities, ji-min han ( . %), min-a shin ( . %), ye-seul han ( . %), hyo-joo han ( . %), and min-jung lee ( . %) were mentioned. from q , to visualize the current accepted configuration that represents korean facial beauty concretely, one of our authors generated a composite face of attractive korean female celebri- ties using the sample average morphing method [ ]. the facial photographs used were selected when more than % of all re- spondents agreed that they represented korean beauty. the process of average morphing works as follows: before morphing the faces, we must obtain very standardized facial photographs with as high resolution as possible. after importing two facial photographs into computer software, automatic photographic size adjustment and cropping were initiated without changing the aspect ratio of the original photographs. then, using a mag- nification tool, independent facial fiducials or feature landmarks, which are generally used in facial photogrammetry, are manually designated by very small dots generated by pointing a computer mouse at each location on two facial photographs shown on the right and left screens. from our experience, to create less blurred faces, because automatic facial feature tracking methods are not correct, we recommend using a manual landmarking method and designating facial fiducials accurately for at least facial landmarks. from this, we found we were able to obtain an aver- age morphing face synthesized by the computer algorithm em- bedded in the software. the composite face was synthesized from faces from the celebrities’ faces rated as most attractive this composite face was generated from the faces of the top most attractive celebrities’ according to respondents (tae-hee kim, ji-hyun jun, hye-kyo song, ga-in han, chae-won moon, young- ae lee, hee-sun kim, yaejin son, eun-ha shim, ye-seul han, suzy bae, and hye-soo kim) along with four recommended celebrities’ faces such as ji-min han, min-a shin, ye-seul han, and hyo-joo han. this composite can be considered a facial image reflective of the facial appearance typically preferred by korean people today. fig. . a composite of an attractive korean face fig. . general attitudes about plastic surgery regardless of job type, . % responded that they were in favor of aesthetic plastic surgery, . % were neutral, and . % opposed. when it came to job type, however, . % of doctors in this study versus . % of the general public responded that they were in favor of aesthetic plas- tic surgery. the public was more likely to be neutral ( . % vs. . %), opposed to ( . % vs. . %), or state that their opinion depends on the cir- cumstances ( . % vs. . %) compared to the doctors in this study. in terms of gender differences (data not shown), . % males versus . % females responded that they were in favor of medical aesthetic procedures. . % of males and . % of females responded that they are neu- tral, . % of males versus . % of females responded that they are opposed to, and . % of males and . % of females stated that their opin- ion depends on the circumstances regarding medical aesthetic procedures. r es po ns e (% ) a+b c d+e f g+h degree of favor . . . . . . a: strongly in favor b: in favor c: neutral d: opposed e: strongly opposed f: depends on circumstance g: not sure h: miscellaneous opinions . . . . . . . . . total public medical rhee sc et al. prototype of an attractive korean face (tae-hee kim, ji-hyun jun, hye-kyo song, ga-in han, chae- won moon, young-ae lee, hee-sun kim, yaejin son, eun-ha shim, ye-seul han, suzy bae, and hye-soo kim) and three ce- lebrities’ faces recommended by respondents ( ji-min han, min- a shin, and hyo-joo han). standardized facial photographs were acquired from the internet by searching the celebrities’ names. then, an attractive composite face was created (fig. ). the composite face is an example of an attractive korean face based on the contemporary aesthetic preferences of korean people. q : the individual influence of each facial aesthetic subunit as perceived by the general public we performed statistical analyses to investigate whether there are significant differences in the influence of individual aesthetic subunits on overall perceived facial attractiveness according to demographic characteristics. the results are summarized in ta- ble . female respondents ( . ) perceived that skin conditio- nis much more important to the perception of facial attractive- ness than male respondents did ( . , t = – . , p = . ). meanwhile, male respondents ( . ) regarded the shape of the lips as a much more important factor in determining facial at- tractiveness than female respondents ( . , t = . , p = . ). in addition, there are significant statistical differences between the genders with regard to the influence of facial bal- ance or harmony (male, . ; female, . ; t = . , p = . ) and the trait of a youthful appearance on attractiveness (male, . ; female, . ; t = . , p = . ). this suggests that male respondents regard those factors as being much more important for facial attractiveness than female respondents do. when we analyzed the results according to age group, the relative degree of importance was somewhat different. respondents ages to ( d) regarded skin condition as the most important factor for facial attractiveness, but there was a different degree of im- portance according to age group ( d, . ; d, . ; and d, . ; d, . ; f = . , p = . ). as a post hoc analy- sis for evaluating group differences, tukey’s test revealed that d respondents regarded skin condition as a far more impor- tant factor for facial attractiveness than respondents aged over did. statistics also revealed that d respondents regarded skin condition as a far more important factor in determining fa- cial attractiveness than d and d respondents did. mean- while, regarding the characteristic of a youthful appearance, its influence on facial attractiveness was statistically different ac- cording to the age group. there was a statistically significant group difference in perception about the importance of youth- fulness for facial attractiveness between the d and d groups ( d, . ; d, . ; d, . ; d, . ; f = . , p = . ). regarding job variables, the general public ( . ) regarded skin condition as a far more important factor for facial attractiveness than doctors ( . ) did (t = – . , p = . ). however, the shape of the nose was regarded as a far more im- portant factor for facial attractiveness by doctors ( . ) than by the general public ( . , t = . , p = . ). discussion there are many reports that suggest that perceptions of the at- tractiveness of faces vary with the gender and race of the respon- dent [ - ]. beauty is an emergent concept composed of objec- tive, subjective, and relational dimensions, and aesthetic plastic surgeons must understand the characteristics of beauty compre- hensively [ , ]. to meet such artistic and scientific demands, being able to understand peoples’ cognition, preferences, and perceptions is very important to plastic surgeons. our questionnaire was categorized and distributed to meet three study objectives. regarding people’s general attitude about plastic surgery, we found that . % of respondents were in fa- vor of aesthetic plastic surgical procedures and only . % of re- spondents were against them. from a gallup korea con- sumer awareness report on appearance and plastic surgery [ ], % of , respondents said that appearance is ‘very impor- tant’ ( % respondents: important to some degree) and only %– % of people regarded people’s appearance as not very or never important. the report noted that % of male and % of female respondents felt that it is acceptable for anyone to under- go plastic surgery to improve their chances of getting a job or for marriage, percentages that have increased gradually since ( % of males and % of females). the report informed us that % of male respondents and % of female respondents had experienced plastic surgery. if we removed gender factors, % ( ), % ( ), and % ( ) of respondents had ex- perienced plastic surgery. although western news outlets have reported that south korea has the highest per capita rate of plas- tic surgery in the world [ , ], their statistics might have been overestimated or there might have been statistical errors because the statistics referenced are based on data from the international society of aesthetic plastic surgery (isaps). the isaps’s sta- tistics are based on survey results from plastic surgeons through- out the world that responded about the number and type of cosmetic procedures they performed over a -year period. the isaps wrote that their survey participants personally complet- ed a questionnaire that primarily focused on the number of spe- cific surgical and non-surgical procedures performed every year. they also wrote that they sent an invitation to approximately , plastic surgeons worldwide to participate in the study vol. / no. / september but only a total of , plastic surgeons responded [ ]. the response rate was only . %. we do not consider these statis- tics to be an accurate representation of views on plastic surgical procedures because there is bias based on the respondents’ pro- fession and attitude toward e-mail questionnaires. we found that although a significant proportion of the korean population is in favor of plastic surgery, a survey from gallup revealed that only a relatively small proportion of the population had under- gone plastic surgery. interestingly, a similar questionnaire study designed for the caucasian population [ ] revealed that % of respondents were currently considering plastic surgery and % stated that they would consider it in the future. although small, the study demonstrates that the seemingly extraordinary boom in plastic surgery in korea may not be as unique as origi- nally perceived. from our survey, it was interesting to find that almost half of our sample of doctors ( . %), which included those interested in cosmetic surgery or procedures but who do not have a specialization from the plastic or dermatologic board, were not in absolute favor of plastic surgery. many doctors who participated in this study stated they were neutral ( . %) and some stated that the decision about plastic surgery depends on the circumstances ( . %), which indicates that many doctors are opposed to the public undergoing thoughtless or imprudent plastic surgery. these practitioners may be dealing with some deal of stress because they are performing cosmetic surgery or procedures after abandoning their own medical specialization (which is currently legal in south korea). in terms of people’s method for getting information about aes- thetic plastic surgery, we found that the mass media was the pri- mary source, reaching . %. among media channels, the inter- net ( . %) was the most important information source, fol- lowed by tv broadcasting ( . %), and newspapers or maga- zines ( . %). however, we know that a considerable amount of plastic surgery information from the internet is either mislead- ing or inaccurate. for example, jejurikar et al. [ ] reported that when they evaluated websites about breast surgery informa- tion, were irrelevant and contained no medical informa- tion. in addition, they found that almost % contained false or misleading information about breast surgery. the same phe- nomenon was observed in website information about liposuc- tion [ ]. unfortunately, the misinformation on plastic surgery can be a grave hindrance with regard to forming good patient and doctor relationships. it is important that official societies of plastic surgeons be actively involved in the design, dissemina- tion, and evaluation of web-based plastic surgery information. we also found, regarding the trustworthiness of information sources, that people regard postoperative surgical outcomes of other people ( . %) and recommendations from acquaintanc- es or relatives ( . %) as critical information for choosing a clinic. in general, people felt that the mass media could not give trustworthy information. only . % of the respondents re- garded information from tv broadcasting as trustworthy. the internet ( . %) and newspapers or magazines ( . %) were re- garded as untrustworthy. among hospital or clinic selection cri- teria, people reported that the three most powerful factors were postoperative surgical results of acquaintances ( . %), exis- tence of doctors’ medical accidents or malpractice, and fame of a doctor. our results are very consistent with findings from a western study about the various factors influencing the selec- tion of a plastic surgeon [ ]. currently, social media has be- come commonplace in our society, and its role in plastic surgery practice development and communication will become more prominent [ , ]. internet advertising is increasingly prevail- ing in korea and becoming a major financial burden for manag- ing a private clinic. we found that people are gradually deciding that such advertising information cannot be a deciding factor when selecting a plastic surgeon, but rather, proof of good surgi- cal results from doctors without malpractice or medical acci- dents and recommendations from acquaintances and relatives are more influential deciding factors. to visualize the configuration of the face currently considered beautiful by koreans, we produced a composite of the faces of attractive korean female celebrities reflective of the respon- dents’ beauty preferences based on the responses provided to q . the composite serves an example for us to better under- stand people’s beauty desires. comparing our results to reports published in [ ], we found that koreans still prefer a small face; wide forehead; smooth malar bones; narrow nose; large eyes; narrow, short, and small chin; wide mouth with a thin upper lip; u- or v-shaped lower face; oval-shaped mandi- ble; relatively pale and fair complexion; clear skin; and stereo- scopic soft tissue. these findings are mostly consistent with the results published by yoon et al. [ ] in as well. regarding the individual influence of each facial aesthetic sub- unit as perceived by the general public, though we did not sur- vey certified plastic surgeons, our results reinforce the data in the reference studies performed in [ , ], showing a consensus with certified plastic surgeons, who usually regard structural factors such as aesthetic appearance of the eyes and a harmonized shape of the face as rather important factors in the cognition of facial attractiveness. among the limitations of our study is the unique demographic profile of the respondents. an inevitable limitation of our study method is that the preference for famous female entertainers’ faces could be more reflective of the entertainers’ social status or personal favorability rather than facial beauty itself; therefore, our survey analysis and the com- rhee sc et al. prototype of an attractive korean face posite face should not be considered an absolute standard. in summary, we found new information on people’s percep- tions of overall facial attractiveness. specifically, skin condition and facial expression are far more important contributors to fa- cial attractiveness than other factors, and beauty perceptions differ somewhat according to the gender of the respondent. our study informs us that contemporary koreans place a high im- portance on skin condition in their assessment of facial beauty, and they take into consideration not only static or structural fa- cial beauty but also the facial expressions they consider attrac- tive. we predict that korean beauty trends will gradually change from a focus on static and structural aspects to dynamic aspects of beauty such as facial expressions in the future. based on this, an increased demand for minimally invasive aesthetic plastic surgical procedures such as refinement and rejuvenation of fa- cial skin can be expected. this is the right time for board certi- fied plastic surgeons to reinforce and broaden our specialized fields to meet contemporary demands based on contemporary concepts of beauty. we have found that the general public in south korea has traditional and unique beauty preferences. we have also found that the structural characteristics of attractive korean female faces have remained unchanged, which was evi- denced by the composite face we generated. in addition, it is worth noting that skin condition and facial expression have be- come important considerations in evaluating facial attractive- ness. beauty perception and cognition were found to differ by the gender of the respondent, but there was little difference in beauty perceptions between the doctors in this study and the general public. our study results provide aesthetic plastic sur- geons with detailed information about contemporary korean people’s attitudes, perceptions, and trends with regard to plastic surgery and the peculiar characteristics of female korean faces that are currently considered to be attractive, which should as- sist plastic surgeons in finding greater focus in their specialized fields or identifying areas that merit more attention. orcid seung chul rhee https://orcid.org/ - - - references . ha jf, longnecker n. doctor-patient communication: a re- view. ochsner j ; : - . . berneburg m, dietz k, niederle c, et al. changes in esthetic standards since . am j orthod dentofacial orthop ; : . . korean standard statistical classification [internet]. dae- jeon: statistics korea; [cited jan ]. available from: http://kssc.kostat.go.kr/ksscnew_web/ekssc/main/ main.do. . rhee sc, lee sh. attractive composite faces of different races. aesthetic plast surg ; : - . . nomura m, motegi e, hatch jp, et al. esthetic preferences of european american, hispanic american, japanese, and african judges for soft-tissue profiles. am j orthod dento- facial orthop ; ( suppl):s - . . cunningham mr , roberts ar , barbee ap, et al. “their ideas of beauty are, on the whole, the same as ours”: consis- tency and variability in the cross-cultural perception of fe- male physical attractiveness. j personal soc psychol ; : - . . chin evans p, mcconnell ar. do racial minorities respond in the same way to mainstream beauty standards? 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proportion of facial aesthetic subunit by korean general public. j korean soc plast reconstr surg ; : - . . lee hb, lee sh, kim js, et al. evaluation of influence of in- dividual facial aesthetic subunits on the congnition of facial attractiveness in public. j korean soc plast reconstr surg ; : - . wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ unseen beauty of flowers – hidden signals or spectacular by-product? note on the cover photograph unseen beauty of flowers – hidden signals or spectacular by-product? the picture on the cover of this issue shows the ultraviolet-induced visible fluorescence of the caucasian stonecrop flower phedimus spurius (sometimes referred to as sedum spurium) collected in stockholm, sweden. under the sunlight, its small and rather unremarkable flowers are uniformly pink or pinkish-white, with only the anthers being distinctly darker. but when these flowers are placed in the total darkness and exposed to the ultraviolet light (uv-a), they completely transform in appearance. the central part of the flower where the bases of stamens and carpels join together and where ovaries are located produces intense blue fluorescence, which strikingly contrasts against the dark magenta fluorescence of the petals, while pollen attached to the anthers shine bright yellow or white. this property of flowers, and many other objects in nature, is a not uncommon but rather insufficiently understood process of ultraviolet-induced visible fluorescence. fluorescence plays a variety of functions in nature, and although it is widely present among different groups of plants and animals, its function is better understood in some organisms and completely unknown in others. for example, fluorescence was shown to contribute towards visual signalling (display or camouflage) in a variety of distantly related groups of animals: in mantis shrimp, jumping spiders, certain marine fish, one species of parrots, etc. (arnold, owens, and marshall ; lim, land, and li ; mazel et al. ; sparks et al. ). its role can go beyond biocommunications. in corals, ultraviolet- and blue-induced visible fluorescence serves multiple functions, depending on the location depth of the corals: in shallow waters, it offers photoprotection due to scattering and converting damaging higher-energy ultraviolet and blue into safe green and red light; in deeper waters, it can enhance photosynthesis by wavelength transformation and back-scattering (salih et al. ). on the other hand, the well- known fluorescence of scorpions is the most puzzling – numerous explanations have been proposed but none is unequivocally proven (gaffin et al. ). ultraviolet-induced visible fluorescence in flowers is common and very variable, both in colours and in patterns: in some flowers, only pollen or anthers “shine” brightly against the weak red fluorescence of chlorophyll in petals; in others, the entire flower can glow. sometimes the entire flower emits the same colour of light, and sometimes different flower parts are differently coloured. but despite considerable research efforts, the function of ultraviolet-induced visible fluorescence in the world of plants remains poorly understood. the fact that fluorescence produces light emission within the visible spectrum may lead some to focus on the visual aspect of it, and to consider it a signalling process of some sort. when fluorescence occurs in plants, the most attractive explanation would be to consider it a part of the mechanism of plant–insect interactions, that it plays the role as a visual signal in attracting pollinators, similar to iridescence and reflectance across the visible to polli- nators part of the spectrum (ultraviolet-to-green or ultraviolet-to-red, chittka and kevan ). it has even been suggested that blue fluorescence of flower parts in wind-pollinated plants, together with observations of insects visiting these flowers, is a visual clue for pollinators collecting pollen (baby et al. ). unfortunately, there is no experimental green letters: studies in ecocriticism, vol. , no. , – , http://dx.doi.org/ . / . . © asle-uki d ow nl oa de d by [n at ur hi st or is ka r ik sm us eu m ] a t : o ct ob er support for these suggestions and it offers no benefit for flowers to attract insects and spare pollen to pollinators, which are unlikely to deliver it to female flower parts. it had also been suggested that fluorescence may contribute to visual appearance of flowers due to combination of fluorescence and reflectance of non-absorbed light (gandía-herrero, garcía-carmona, and escribano ). however, models that account for the percentage of ultraviolet radiation in sunlight; the efficiency of fluorescence (the amount of absorbed ultraviolet light and the percentage of its energy converted into visible light); the reflec- tivity of flowers in parts of the spectrum visible to pollinators; and the sensitivity of the eyes of prospective pollinators confirm that fluorescence is not strong enough to contribute substantially to the visual signalling under normal conditions (iriel and lagorio ). one more study that adds to the confusion showed experimentally that ultraviolet-induced blue fluorescence in pitcher plants plays important role in attracting prey insects, suggesting that fluorescence is visible under natural conditions to at least some animals (kurup et al. ). the next hypothesis states that ultraviolet-induced visible fluorescence produces light that may be used in photosynthesis in vegetative parts of plants, such as leaves and stems (garcía-plazaola et al. ). it does make sense for organisms that live in the aquatic environment with narrow-band ultraviolet-blue illumination, which needs to be converted to green light before being absorbed by the chlorophyll. but would visible light produced through ultraviolet-induced visible fluorescence contribute enough energy for photosynth- esis in plants illuminated by unfiltered sunlight? besides, since photosynthesis is not the major function of flowers per se, a photosynthetic function of fluorescence in this case is even less likely. the number of compounds in plants that emit visible fluorescence under the ultravio- let light is large (garcía-plazaola et al. ), they are widely distributed among plants and tissues and many of them have vital functions that are not related to wavelength transformation. even if in some species of plants, ultraviolet-induced visible fluorescence may indeed play some role in visual signalling, it is most probably not the only its function. could the fluorescence in plants be simply the result of photoprotective mechan- isms, which shield dna in reproductive cells (pollen, ovules) from damaging effects of the ultraviolet radiation, by converting it into less harmful visible light, as suggested by some (baby et al. )? finally, could it be just a by-product that does not really have a defined function of its own? disregarding its actual function in nature, ultraviolet-induced visible fluorescence of flowers may be a powerful visual signal for people. although it cannot be observed without a few simple tools and key safety precautions, fluorescence presents ordinary, sometimes mundane flowers in an unusual and aesthetically pleasing way. the unseen beauty of flowers is revealed. references arnold, k. e., i. p. f. owens, and n. j. marshall. . “fluorescent signaling in parrots.” science : . doi: . /science. . . . baby, s., a. j. johnson, b. govindan, s. lukose, b. gopakumar, and k. c. koshy. . “uv induced visual cues in grasses.” scientific reports : . doi: . /srep . chittka, l., and p. g. kevan. . “flower colour as advertisement.” in practical pollination biology, edited by a. dafni, p. g. kevan, and b. c. husband, – . cambridge, on: enviroquest. gaffin, d. d., l. a. bumm, m. s. taylor, n. v. popokina, and s. mann. . “scorpion fluorescence and reaction to light.” animal behaviour : – . doi: . /j.anbehav. . . . note d ow nl oa de d by [n at ur hi st or is ka r ik sm us eu m ] a t : o ct ob er http://dx.doi.org/ . /science. . . http://dx.doi.org/ . /srep http://dx.doi.org/ . /j.anbehav. . . gandía-herrero, f., f. garcía-carmona, and j. escribano. . “botany: floral fluorescence effect.” nature : . doi: . / a. garcía-plazaola, j. i., b. fernández-marín, s. o. duke, a. hernández, f. lópez-arbeloa, and j. m. becerril. . “autofluorescence: biological functions and technical applications.” plant science : – . doi: . /j.plantsci. . . . iriel, a., and m. g. lagorio. . “is the flower fluorescence relevant in biocommunication?” naturwissenschaften : – . doi: . /s - - - . kurup, r., a. j. johnson, s. sankar, a. a. hussain, c. s. kumar, and b. sabulal. . “fluorescent prey traps in carnivorous plants.” plant biology : – . doi: . /j. - . . .x. lim, m. l. m., m. f. land, and d. li. . “sex-specific uv and fluorescence signals in jumping spiders.” science : . doi: . /science. . mazel, c. h., t. w. cronin, r. l. caldwell, and n. j. marshall. . “fluorescent enhancement of signaling in a mantis shrimp.” science : . doi: . /science. . salih, a., a. larkum, g. cox, m. kühl, and o. hoegh-guldberg. . “fluorescent pigments in corals are photoprotective.” nature : – . doi: . / . sparks, j. s., r. c. schelly, w. l. smith, m. p. davis, d. tchernov, v. a. pieribone, and d. f. gruber. . “the covert world of fish biofluorescence: a phylogenetically widespread and phenotypically variable phenomenon.” plos one ( ): e . doi: . /journal. pone. . oleksandr holovachov swedish museum of natural history, stockholm, sweden oleksandr.holovachov@nrm.se green letters: studies in ecocriticism d ow nl oa de d by [n at ur hi st or is ka r ik sm us eu m ] a t : o ct ob er http://dx.doi.org/ . / a http://dx.doi.org/ . /j.plantsci. . . http://dx.doi.org/ . /s - - - http://dx.doi.org/ . /j. - . . .x http://dx.doi.org/ . /science. http://dx.doi.org/ . /science. http://dx.doi.org/ . / http://dx.doi.org/ . /journal.pone. http://dx.doi.org/ . /journal.pone. perception and deception: human beauty and the brain behavioral sciences review perception and deception: human beauty and the brain daniel b. yarosh retired svp basic science research, estée lauder co., merrick, ny , usa; dyarosh@danyarosh.com received: february ; accepted: march ; published: march �� abstract: human physical characteristics and their perception by the brain are under pressure by natural selection to optimize reproductive success. men and women have different strategies to appear attractive and have different interests in identifying beauty in people. nevertheless, men and women from all cultures agree on who is and who is not attractive, and throughout the world attractive people show greater acquisition of resources and greater reproductive success than others. the brain employs at least three modules, composed of interconnected brain regions, to judge facial attractiveness: one for identification, one for interpretation and one for valuing. key elements that go into the judgment are age and health, as well as symmetry, averageness, face and body proportions, facial color and texture. these elements are all costly signals of reproductive fitness because they are difficult to fake. however, people deceive others using tricks such as coloring hair, cosmetics and clothing styles, while at the same time they also focus on detecting fakes. people may also deceive themselves, especially about their own attractiveness, and use self-signally actions to demonstrate to themselves their own true value. the neuroscience of beauty is best understood by considering the evolutionary pressures to maximize reproductive fitness. keywords: facial beauty; attractiveness; evolutionary biology; costly signals; cosmetics; deception; self-signaling . introduction human nature includes a desire to be attractive, and historically much of the fine arts are depictions of human beauty. much time, money and emotional energy are spent in improving our appearance to reach a goal of beauty. people feel better about themselves when they think they are attractive to others. we devote portions of our brains to evaluating characteristics of attractiveness that are remarkably similar among cultures. our bodies are shaped not only for function but also to match the image of attractiveness to others. the simple answer that “beauty is for attracting mates” is no longer sufficient to explain the wealth of data on human preferences for beauty. attractiveness is part of our status ranking among our same-sex peers, and we actively deceive others and ourselves about our personal appearance. this review is crafted to place the study of personal appearance and beauty in the context of evolutionary biology. this theoretical framework best explains the quirkiness, universality and unexpected behaviors of people striving to be attractive and seeking out beautiful people. . the evolutionary biology of beauty the principle of evolutionary biology is that when there is genetic variation within a population of a characteristic that improves the individual’s chance of survival and reproduction (sending its genes into several succeeding generations), that characteristic with the best improvement will be naturally selected over other forms and becomes more common within the population. eventually that behav. sci. , , ; doi: . /bs www.mdpi.com/journal/behavsci http://www.mdpi.com/journal/behavsci http://www.mdpi.com http://www.mdpi.com/ - x/ / / ?type=check_update&version= http://dx.doi.org/ . /bs http://www.mdpi.com/journal/behavsci behav. sci. , , of characteristic phenotype will become nearly universal, and the genetic variant producing the favored phenotype will become “fixed” in the population. some phenotypes improve an individual’s acquisition of food, such as running stamina or manual dexterity. however, those phenotypes that directly improve the chances of reproduction, such as attracting mates and obtaining help in raising children, are under even stronger selection pressure, since they directly influence the frequency with which those genes are passed to the next generation. . . reproductive strategy men and women have different strategies for reproductive success that were honed during tens of thousands of prehistoric years. women seek men for partners who will contribute material resources as well as good genes to their children, while men seek one or more female partners with good genes, some of whom they may provide with resources. the strategy of each sex includes advertising to potential mates, and competing members of the same sex, to demonstrate that he or she is valuable (reviewed in [ ]). the display of these traits is called “attractiveness” or “beauty”. . . universality of attractiveness judgements assessments of attractiveness are surprisingly similar between men and women and among groups of people. a meta-analysis, covering studies and over , observers, reported that people agree, both within cultures and across cultures, who is attractive and who is not [ ]. men and women as well as people of all ages agree on who is attractive. this strongly suggests that judgments of physical attractiveness are hard-wired in human genetics, likely fixed at an early stage in our evolution. these assessment tools are available at a remarkably early stage of human development. six-month-old infants gazed longer at faces judged by adults as attractive and spent less time looking at faces that were judged as not attractive [ ]. . . attractive people succeed judgments of attractiveness have real consequences because they are cues of a person’s health and fitness, which indicate the ability to donate good genes and successfully raise children. attractiveness is the most important predictor of who gets the preferred choice in mates [ ]. in fact, in the modern world, physical attractiveness is significantly associated with reproductive success [ ]. a woman who chooses a male partner who contributes not only good genetic material but also provides resources will on average be more successful than a woman without such support [ ]. this means that attractiveness and the ability to accurately detect attractiveness are under evolutionary selective pressure. therefore, it is not surprising that the brain has developed specialized systems to accurately assess attractiveness characteristics, such as age, health and reproductive potential. . the neuroscience of facial recognition . . brain loci the most extensive research on the brain regions used in assessing beauty has been reported for facial recognition [ ] and less research has been reported on body judgments [ ]. brain loci used to judge the beauty of faces are distinct in distribution and activation intensity from those used to assess the beauty of non-facial visual art [ ], reflecting the evolutionary salience of facial beauty. while a few loci have been linked together to suggest a pathway for the evaluation of beauty, this is not to suggest that this is the only way the brain makes these judgments and, under special conditions, the plasticity of the brain may invoke other regions to participate in reaching assessments. the brain uses at least three modules, or cognitive domains, in deciding the value of attractiveness. the occipital and temporal regions of the cortex are used first to process face views [ ]. the inferior occipital gyri (iog) perceives facial features and passes the information to the fusiform face area (ffa) of the fusiform gyrus (fg) for facial recognition [ ]. the ffa recognizes and processes the location of behav. sci. , , of facial features (especially the eyes, nose, and mouth) and their spacing [ ]. people have distinct eye movement patterns (scan path routines) when they judge unfamiliar faces [ ], and they simultaneously engage the ffa region during this routine [ ]. damage to the ffa causes prosopagnosia, a condition in which patients are unable to recognize faces by sight or accurately judge facial attractiveness, although they can recognize the same people by voice [ , ]. the fg very quickly responds more strongly to attractive faces than unattractive ones [ ], suggesting that the ease of recognition of attractive features occurs perhaps even before the rest of the brain is included in the evaluation. the iog connects to the second module, including the superior temporal sulcus (sts) for interpretation of facial movement, such as eye gaze, lip movement and facial expressions [ ]. the ffa and iog then interact with other brain regions, such as the occipital face area (ofa) and the ventral anterior temporal lobes (vatls) for feature abstraction and assessment [ ], and the amygdala, insula and limbic system for the emotional content of facial expressions and movement [ ]. information from the sts is also passed to the third module, the orbitofrontal cortex (ofc), including the nucleus accumbens, for making judgments of beauty and producing the neurological rewards (dopamine and other neurotransmitters) for finding it [ ]. the ofc responds with greater activity to attractive versus unattractive faces [ ]. when men were shown faces of beautiful women while their brains were scanned by fmri, the attractive faces specifically activated the nucleus accumbens in the caudate region of the brain, when compared to viewing average faces [ ]. transcranial stimulation of the dorsolateral prefrontal cortex (dlpfc) increased the perceived attractiveness of faces but did not affect other facial judgments such as age [ ]. these studies suggest that the value but not the features of the face are decided in these third module cortical regions. human bodies, both self and others, are selectively perceived in the temporal lobes by the extrastriate body area (eba) and the fusiform body area (fba), whether they are full body representations, stick figures or silhouettes [ ]. the ofc, particularly the nucleus accumbens and anterior cingulate cortex, are then used in judging the beauty of nude bodies [ ]. similar regions of the brain are used in evaluating sculptures and similarly posed real human bodies [ ]. . . gender-specific brain activation male and female brains activate differently while evaluating appearance and beauty, consistent with their differences in reproductive strategy. for heterosexuals, opposite-sex faces stimulate assessment and reward brain systems, such as the amygdala, cingulate and insular cortices, more than same-sex faces, signifying they hold greater salience [ ]. both heterosexual men and women favor viewing attractive faces, but men willingly expend more effort to view beautiful women’s than men’s faces, while women spend less energy, and equivalent amounts, to view both beautiful men’s and women’s faces [ ]. men show slower response times to beautiful faces than women, evidencing greater cognitive load while processing attractive faces [ ]. consistent with this, brain imaging studies show that the ventromedial prefrontal cortex (vmpfc) of male subjects is more sensitive to physical attributes, such as the youthfulness and gender of faces, than female subjects [ ]. . appearance and beauty judgments . . gender differences in attractiveness features and perception the sex hormones, testosterone in men and estrogen in women, largely drive the body and facial features that define attractiveness, and also reshape the brain to detect and value these features. the onset of puberty ramps up hormone levels and reshapes the male and female bodies. men increase their shoulder to waist ratio, their beards grow, and their jawlines become more pronounced. for women, breasts develop, the hips to waist ratio increases, and their jawlines and facial features become softer. several regions of the brain express either estrogen/progesterone receptors or androgen receptors, and brain structure and responses are, therefore, on different developmental trajectories in men and women beginning in puberty [ ]. behav. sci. , , of women are so attuned to the facial features of men that simply by looking at their photographs they can correctly rank order a group of men based on their saliva testosterone level [ ]. interestingly, while a woman tends to prefer a man with high testosterone for an affair, she prefers a little less testosterone for a long-term mate, and her parents (who might have to help take care of any babies if the man leaves) tend to prefer even a little less testosterone [ ]. exaggerating the masculinity of men’s pictures actually makes them less attractive [ ]. on the other hand, estrogen monotonically drives female beauty [ ]. panels of men and women were shown women’s faces that were morphed to exaggerate feminized features, and % of men and women decided that the feminization of women’s faces made them more attractive. the same result was found for faces of european, african and asian descent [ ]. in another study, estrogen was measured in women over the course of their monthly cycles. both men and other women rated their attractiveness. women with higher estrogen levels had higher ratings of femininity, attractiveness and health. interestingly, when the women wore color cosmetics, the correlation disappeared, suggesting that makeup literally “makes up” for lower estrogen levels [ ]. . . age perception youth is a major component of facial attractiveness [ ] and underlies most of the specific characteristics people look for in judging attractiveness. older faces are judged as less attractive, less likeable, less distinctive, and less energetic [ ]. the appearance of aging past the prime of life is an assault on self-esteem and confidence [ ]. in particular, age is used, along with other skin and body signs, to assess standing in the community, desirability as a partner, and reproductive potential [ , ]. traditionally, men more than women tend to accumulate resources with age (which makes them more attractive partners), while women more than men tend to lose fertility with age. as a result, the sharp decline in attractiveness with women’s age after menopause is largely driven by male perception, while the perception of increased power of men with age is predominantly due to female opinions [ ]. people are exquisitely sensitive to the age of others and are excellent judges of each other’s age, with a correlation coefficient of perceived to actual age of . [ ]. just by viewing a swatch of skin people are able to correctly judge age, with a correlation coefficient of more than . [ ]. the most important factors in judging age from facial images are the size of the eyes and the lips, and the evenness of skin tone, regardless of what that tone might be [ ]. . . health perception people use specific cues from the appearance of others to make judgments about that person’s health, including the history as well as the current state of health. assessments of health often overlap assessments of age in determining beauty, such as in the case of the sclera, or white part of the eyes. sclera become darker and colored with age or poor health, and the whiteness of sclera are strongly correlated with the perception of youth, health and attractiveness [ ]. . . symmetry throughout the animal kingdom, and certainly among people, body symmetry is a strong signal of past and present health. bilateral symmetry is a sign of the absence of congenital or developmental defect, malnutrition or parasitic infection, all of which are common maladies in subsistence living [ ]. although minor variations are often of no functional consequence, they do have dramatic impact on the perception of beauty [ ]. the absence of a history of pathology is a good sign of reproductive fitness and the preference for symmetry is culturally universal [ ], suggesting that it is hard-wired into brain judgments by natural selection and not derived from culture. women prefer men with symmetrical faces and can select symmetrical men from their scent [ ]. unfortunately for cologne manufacturers, the scent of androstenone is an unpleasant under-arm smell. behav. sci. , , of her preference for symmetry is even heightened during a woman’s fertile phase of her monthly cycle [ ], an effect found for several female preferences that is called ovulatory shift. . . average features sir francis galton, a cousin of charles darwin and the inventor of fingerprinting, was studying the faces of criminals to identify diagnostic facial features and was the first to report that the average face prepared by composites of criminal faces is more attractive than individual faces [ ]. the preference for the average is found among all cultures [ ] and strengthens as children develop after years of age [ ]. interestingly, male preference for women’s faces is correlated to facial averageness, but women’s self-perceived attractiveness is not correlated with their averageness [ ]. there may be several reasons for the preference for average facial features. one trivial explanation is that the preparation of composites tends to smooth out asymmetrical or uneven features of individuals. a second is that the very nature of cultural learning favors the most common feature or practice [ ]. a third is that, assuming facial features are under genetic control and are adaptive, natural selection will favor a fitness peak that we perceive as average compared to the less fit facial forms. finally, the beauty of average may lie in the fact that it is most expected and imposes the least cognitive load to recognize and interpret [ ]. despite the preference for average, exaggerating some key facial features actually improved the attractiveness of faces [ ], meaning that average is attractive, but unusually endowed faces may be more attractive. this phenomenon (found throughout the animal kingdom) is termed signal shift: a preference for an elemental characteristic, and a heightened preference for the extreme form [ ]. the signal shift response may identify a simple characteristic the brain overweighs in valuing faces. there is a limit to the attractiveness of exaggerated features, and an extreme form that is outside the range of normal experience causes extra work for the brain, which then considers the form weird and ugly. . . face proportions as social creatures, humans read other people’s intentions and emotions in their faces and adjust their behavior accordingly. people also view the face as an important determinant of attractiveness, which is a signal of reproductive fitness. as discussed previously, people of both sexes and nearly all cultures agree on which faces are attractive and which are not. the features people find attractive are shaped in part by sex hormones, including stronger or softer jaw and larger or smaller eye shape [ ]. however, the cognitive processes that determine attractiveness are not always accessible to consciousness. composites were prepared from a group of college students, one composite from those judged most attractive and another from those judged least attractive [ ]. people who view the two composites side by side can agree on which is more attractive, but it is difficult to put into words which features lead to the decision. the eyes are a specific target of the human face for social interaction and beauty assessment. the brain uses a special region, the superior temporal sulcus, for the job of following eye movements in others and determining the direction of their view [ ]. this region develops early, and neonates learn within months to follow their mothers’ gaze [ ]. eye recognition is wired directly into the most fundamental emotional processing unit in the brain—the amygdala [ ]. by contrast, the prominence of the ears and nose are not signals of beauty, because the length of both the ears [ ] and nose [ ] relative to the rest of the face continue to increase with age. . . body proportions body shape is also a signal of reproductive fitness. people universally have a preference for shape as expressed in the ratio of waist to hips for men of . , and waist to hips for women of . [ ]. in one study, men were shown pictures of naked women before and after surgery that improved their waist-to-hip ratio to be closer to . and found that approaching the ideal specifically activated the behav. sci. , , of orbitofrontal cortex and the anterior cingulated cortex [ ], regions that are also used in judging the attractiveness of faces. these preferences arise early, with children as young as -years-old selecting canonical body shapes over those with altered legs to trunk ratios [ ]. the movement of other people is also of great interest to social humans. the extrastriate body area (eba) of the occipitotemporal area is selectively activated in evaluating human bodies and movement [ ] and such activation for heterosexuals is greater for opposite-sex bodies than same-sex bodies [ ]. . . foot size as women age and bear children, the size of their feet relative to their height increases [ , ]. a proportionately small foot is therefore a signal of youth and untapped reproductive potential. not surprisingly, both men and women prefer small feet in women. in a series of studies, images of both men and women were altered to increase or decrease the size of the foot relative to height. observers of the images, both men and women, preferred the natural proportion of foot to height in men over exaggerated smaller or larger feet. but they predominately judged the disproportionately smaller foot of women as more attractive than the natural proportion [ , ]. high heeled women’s shoes achieve the appearance of a smaller foot by raising the heel relative to the toe and shortening the distance from the heel to the toe in the footprint. the shoe generally just covers the toes and not the instep, further accentuating the appearance of a small step. . . facial color and wrinkles despite the variation in underlying skin tones, the homogeneity of skin color is correlated with increased attractiveness and appearance of healthiness in every culture examined [ , ]. people who view a cropped image of a cheek were able to accurately judge age, based on the homogeneity of skin tone [ ]. in traditional chinese medicine, skin color is used as a diagnostic tool for disease [ ]. among caucasians, men perceive red tones in women’s faces as more attractive than less red faces because it is viewed as a sign of health. [ ]. for these women, red facial coloration tracks their level of estradiol, and facial coloration may provide men with cues about fertility [ ]. facial color gradient is also important because as skin color gets darker with age, the color contrast between the hair, eyes and facial skin is reduced [ ]. this is a consistent finding among many ethnic groups, including caucasians, chinese, latin americans and south africans [ ] wrinkling increases with age and sun exposure and is a strong signal for judging age [ ]. the discoloration of skin with age is interpreted as a loss of health, while wrinkling is perceived as a sign of age and loss of fertility [ ]. . costly signals and deception . . costly signals the brain has evolved its focus on these features of attractiveness and beauty because not only are they reliable measures of health and reproductive fitness, but they are (or have been for most of our evolutionary history) difficult to fake. such features that genuinely signal reproductive fitness are known as costly signals [ ]. costly signals that are specific to one sex or the other are subject to strong sexual selection. one sex prefers a feature signaling reproductive fitness and chooses partners who have that feature. the next generation produces one sex that favor the costly signal and the other sex that displays it. this is called the green beard effect, after the hypothetical example of two sets of genes that co-evolve, one set that produces a green beard in males and another set that prefers a green beard in females. this can lead to the run-away evolution of exaggerated features, such as extraordinarily large elk antlers or peacock feathers. the key element is that the costly signal must be biologically difficult to produce, or else fakers without the necessary reproductive fitness will display the feature and gain unwarranted mating opportunities. behav. sci. , , of most if not all of the characteristics described here as signs of attractiveness and beauty are costly signals. they reflect healthy development, absence of disease, and display the level of sex hormones that reflect fertility. human culture has added body ornaments and possessions to costly signals. these are additional signs of wealth and resource acquisition that also signal reproductive fitness, including decorative clothing and jewelry, lavish housing and luxury possessions. . . deception humans have also devised ways by which they deceive others as to their true reproductive fitness by faking costly signals. . . . makeup and cosmetics women around the world apply makeup to alter their appearance. facial recognition by the brain is made more difficult by heavy makeup, especially if the face was first seen without makeup [ ]. makeup can be so deceptive that it impairs automated facial recognition software [ ]. as noted before, the application of makeup overcomes the influence of fluctuating estrogen levels on perceptions of attractiveness [ ]. by darkening hair color and lightening skin complexion, cosmetics are used to counter this sign of aging by enhancing contrast [ ]. cosmetics also even out skin tone, and for people shown pictures of both made-up and no makeup faces, the number of eye fixations and dwell time were positively correlated with skin color homogeneity [ ]. overall, makeup reduces the perceived age of women, and the older the woman, the greater the reduction of the perceived age [ ]. this has significant social benefits, since the use of makeup leads to an increase in the perception of likability, competence and trustworthiness [ ], as well as dominance and prestige [ ]. eye makeup increases the appearance of the size of women’s eyes [ ] and has the greatest effect on attractiveness as judged by both men and women [ ]. observers look at the eyes of women with eye makeup % longer than women without it, and if the rest of the face is made up, the attention to the eyes increased % [ ]. lipstick, which increases the appearance of the size and accentuates the shape of the lip, increases the time people spend looking at the lips by % [ ]. deception by cosmetics has measurable economic consequences. male patrons at a french restaurant gave tips more often to waitresses who wore makeup and, when they did tip, they gave them larger amounts of money than to waitresses without makeup. there was no difference for female patrons, even though both male and female patrons thought that the waitresses were more attractive when they wore makeup [ ]. in macroeconomic theory, the lipstick effect (first formulated by cosmetics magnate leonard lauder) is the increase in sales of lipsticks during economic downturns, as women turn to small pleasures to compensate for losses and increase their appearance advantage in a more competitive environment. a review of recessions over the past years confirmed that during downturns women tend to increase their purchase of products that enhance their appearance while decreasing their purchase of non-appearance-enhancing products [ ]. . . . deception detection maintaining the value of costly signals against deception requires that people are able to detect and punish cheating. within the brain, the frontal lobe and amygdala are key components of the “lie detector”, as demonstrated by a patient with brain damage in this region who was unable to detect cheating, even though otherwise cognitively normal [ ]. the brain is especially attuned to negative information, emphasizing the importance of detecting fakes and posers. test subjects were significantly more likely to retain and consciously process a human face if it was associated with negative gossip rather than positive or neutral gossip [ ]. since women have the greater stake in detecting who is or is not faking costly signals among potential mates and rivals, it is not surprising that many studies have shown that women outperform men in detecting lies and inferring emotions from subtle cues [ ]. behav. sci. , , of . . self-deception and self-signaling the best way to convince others of a lie is to believe it yourself, and natural selection is strong enough to build a genetically controlled self-deception mechanism [ ]. many studies suggest that people are objectively accurate in evaluating others but view themselves with an optimism bias. . . . self-assessment people agree with a correlation of . about the attractiveness of others, but correlations between self-ratings and objective measures of individual attractiveness are remarkably low: . for men and . for women [ ]. people maintain an image of themselves that is much better than others perceive. for example, photographs of volunteers were morphed to make them progressively more attractive or less attractive. the subjects, both western europeans and asians, were then invited to pick out from the array of pictures the one that was the accurate representation of themselves. the median choice was a picture that was % more attractive [ ]. they were also quicker to recognize the more attractive photo than their actual photo, a revealing result considering that people recognize objects more quickly when they match their mental representations. . . . self-deception the brain can hold a truthful and false belief at the same time because it is composed of domain-specific cognitive modules, each of which evolved for solving a specific problem [ ]. for example, the medial prefrontal cortex (mpfc) is integral to processing self-related information but remains quiet when the brain considers non-self-referential information [ ]. these modules are not tightly connected and not all are accessible to consciousness. often, these modules reach a decision which is only later rationalized by conscious thought [ ]. facial attractiveness is so salient to people that it can influence unrelated opinions, such as the perception of fairness. in the ultimatum game, a player is offered an arbitrary split of money by a proposer, which he can either accept or reject as unfair. male players accepted offers as fair from attractive women that they rejected when proposed by unattractive women [ ], suggesting that a man can deceive himself into believing an offer is fair just because the proposer is beautiful. . . . self-signaling since the world is a competitive place, people are concerned with their own level of reproductive fitness and social status. however, they cannot know their own status with any certainty, in part because they lie to themselves about their own value. therefore, they use various signals to themselves to demonstrate their own value [ ], such as overcoming challenges or acquiring costly goods or making generous donations, even when no one else knows about it. self-signaling explains many behaviors of people in secret, private or anonymous purchasing or charity transactions [ ]. many efforts by people to alter or improve their appearance beyond what is conventional or apparent to others, such as some types of cosmetic surgery and even piercings or tattooing on body sites covered by hair or clothing, may be understood as a signal to oneself. . conclusions dr. theodosius dobzhansky, the famous geneticist, wrote in that “nothing in biology makes sense except in the light of evolution”. since the human form and the brain co-evolved in the million years since our last common ancestor with the apes, we can say that nothing in beauty makes sense except in light of the brain. natural selection favors individuals with greater reproductive fitness and also those who display signs of greater fitness, as well as those who can detect them. the costly signals of fitness for humans include health, youth, and ideal proportions. the brain has evolved modules to perceive facial and body shapes, interpret their meaning, and then assign value—beautiful and attractive, or not. since men and women have different reproductive strategies, behav. sci. , , of and different sex hormones shape their bodies, the brain is tuned to those features driven by these gender-specific development patterns in reaching decisions about attractiveness. a key finding is that men and women of all cultures agree on which men and women are attractive and who are not. people use cosmetics and surgical procedures to fake costly signals, while at the same time they are always on the lookout to detect cheaters. deceivers are more convincing when they believe the lie themselves, and we have ample evidence of self-deception in beauty. in this fog of competition, people use self-signaling to indicate to themselves their own worth. none of this makes sense except in light of the neuroscience of beauty. funding: this research received no external funding. conflicts of interest: the author declares no conflict of interest. references . bovet, j. the evolution of feminine beauty. in exploring transdisciplinarity in art and sciences; kapoula, z., volle, e., renoult, j., andreatta, m., eds.; springer international: heidelberg, germany, ; 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[crossref] . bodner, r.; prelec, d. self-signaling and diagnostic utility in everyday decision making. in collected essays in psychology and economics; brocas, i., carillo, j., eds.; oxford univ. press: oxford, uk, . . yarosh, d. why luxury is valuable: status aspirations and self-signaling create premium value in luxury consumers goods. available online: http://www.danyarosh.com/why-luxury-is-valuable.html (accessed on january ). © by the author. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /). http://dx.doi.org/ . /p http://dx.doi.org/ . /bjop. http://dx.doi.org/ . /journal.pone. http://dx.doi.org/ . / http://dx.doi.org/ . /aca http://dx.doi.org/ . /j.jaad. . . http://dx.doi.org/ . /a http://dx.doi.org/ . /science. http://dx.doi.org/ . / - . . . http://dx.doi.org/ . / http://dx.doi.org/ . /pnas. http://dx.doi.org/ . /fnins. . http://www.danyarosh.com/why-luxury-is-valuable.html http://creativecommons.org/ http://creativecommons.org/licenses/by/ . /. introduction the evolutionary biology of beauty reproductive strategy universality of attractiveness judgements attractive people succeed the neuroscience of facial recognition brain loci gender-specific brain activation appearance and beauty judgments gender differences in attractiveness features and perception age perception health perception symmetry average features face proportions body proportions foot size facial color and wrinkles costly signals and deception costly signals deception makeup and cosmetics deception detection self-deception and self-signaling self-assessment self-deception self-signaling conclusions references nature precedings skip to main content thank you for visiting nature.com. you are using a browser version with limited support for css. to obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in internet explorer). in the meantime, to ensure continued support, we are displaying the site without styles and javascript. advertisement view all journals search my account login explore content journal information rss feed nature nature precedings welcome to nature precedings pre-publication research and preliminary findings for the life science community from until . advertisement browse articles finding bicliques in digraphs: application into viral-host protein interactome malay bhattacharyya sanghamitra bandyopadhyay ujjwal maulik presentation apr co-expression toggling of micrornas in alzheimer’s brain malay bhattacharyya poster apr inhaled insulin: intrapulmonary or intranasal? danish ahmed sweta kumari shivangi jaiswal poster apr better analysis, better acceptance ‐take up the challenge of publishing in bioinformatics malay bhattacharyya presentation apr mapping from statistical to biological proximity malay bhattacharyya presentation apr some concepts of graph theory malay bhattacharyya presentation apr integration of co-expression networks for gene clustering malay bhattacharyya sanghamitra bandyopadhyay presentation apr mining the largest quasi-clique in human protein interactome sanghamitra bandyopadhyay malay bhattacharyya presentation apr mining co-expression graphs: applications to microrna regulation and disease analysis malay bhattacharyya presentation apr explore content research articles news & comment rss feed journal information about precedings search search articles by subject, keyword or author show results from all journals this journal search advanced search quick links explore articles by subject find a job guide to authors editorial policies nature precedings issn - (online) nature.com sitemap about us press releases press office contact us discover content journals a-z articles by subject nano protocol exchange nature index publishing policies nature portfolio policies open access author & researcher services reprints & permissions research data language editing scientific editing nature masterclasses nature research academies libraries & institutions librarian service & tools librarian portal open research recommend to library advertising & partnerships advertising partnerships & services media kits branded content career development nature careers nature conferences nature events regional websites nature africa nature china nature india nature italy nature japan nature korea nature middle east legal & privacy privacy policy use of cookies manage cookies/do not sell my data legal notice accessibility statement terms & conditions california privacy statement © springer nature limited \ < d f f f d cce e e f ede f eee edfbe eef edeef e ede ff b e f > СТРАТАГЕМА КРАСОТКИ: ТЕОРИИ «МЯГКОЙ СИЛЫ» С КИТАЙСКОЙ СПЕЦИФИКОЙ Е.В. Журавлева Кафедра теории и истории международных отношений Российский университет дружбы народов ул. Миклухо-Маклая, / , Москва, Россия, На данный момент в мировой научной литературе существует не одно определение и не одно обозначение понятия «мягкая сила». В англоязычных трудах в основном принят термин «soft power», в русскоязычных исследованиях чаще встречается «мягкая сила», реже «мягкая власть», в китайской историографии также довольно разнообразная терминология: жуань шили, жуань лилян и жуань цюаньли (软实力, 软力量 и 软权力). Разнообразие терми- нов отражается и в разнообразии трактовок системы или механизма работы «мягкой силы», что позволяет сделать вывод, что на данный момент не сформировалось единой концепции и подхода к ее изучению. Предметом данного исследования служит «мягкая сила» в рамках концепций зарубежных и российских исследователей. Перед автором был поставлен ряд задач, среди которых: определить место политики «мяг- кой силы» во внешнеполитическом курсе КНР, проанализировать существующие интерпрета- ции и концепции «мягкой силы с китайской спецификой», а также проследить развитие теорий «мягкой силы». В результате проведенного исследования автор приходит к выводу, что несмотря на раз- личие в трактовках, есть и общие аспекты, в том числе: большинство исследователей полага- ют, что само понятие непосредственно связано с влиянием субъекта на объект, а также что среди основных инструментов «мягкой силы» зачастую выделяются гуманитарное сотрудни- чество, инвестиции, диалог на высшем уровне и др. Данное исследование позволяет не только сформировать представление о «мягкой силе» через призму различных научных изысканий, но и выявить ключевые элементы системы, а также альтернативные способы применения политики «мягкой силы» субъектом и варианты ее усиления. Ключевые слова: теория «мягкой силы», Китай, soft power, внешняя политика КНР, со- вокупная мощь государства. Концепция «мягкой силы» государства, или «мягкой власти», у английского аналога power есть несколько значений, и если рассматривать понятие в контексте именно силы, то это будет скорее движущая или побуждающая сила, то, что при- водит определенный механизм в действие. Если же рассматривать power в значе- нии «власть», то можно увидеть уже конечный результат: то, чего субъект «мяг- кой власти» уже достиг посредством различных инструментов. В российской историографии наиболее распространен термин «мягкой силы», популярность такой трактовки можно объяснить и тем фактом, что масштаб силы можно изме- рить и он более динамичен, в отличие от масштабов власти. В китайской историографии встречается ряд различных наименований «мяг- кой силы», включая жуань шили, жуань лилян и жуань цюаньли (软实力, 软力量 и 软权力). [pang zhongying : ] Все термины несмотря на то, что отражают Вестник РУДН, серия Международные отношения, март , том , № одно и то же понятие, несут несколько разную смысловую нагрузку. Первое, наи- более часто употребляемое, дословно можно перевести как «мягкая реальная/ действительная сила», что противоречит утверждениям, что «мягкая сила» нема- териальна. Второй термин означает «мягкая сила», при чем, как правило, термин лилян (力量) чаще используется для обозначения физической мощи субъекта, что снова подчеркивает весьма прагматичный и вполне материальный подход к тер- мину. И, наконец, третье понятие жуань цюаньли (软权力) отражает скорее пра- вовой характер «мягкой силы», дословно можно трактовать сразу в нескольких вариантах, а именно: «мягкая власть», «мягкое полномочие/право» и т.д. Исполь- зование последнего термина, скорее, описывает право каждого субъекта на ис- пользование «мягкой силы». Весьма прагматичную трактовку цюаньли (权力) дают китайские исследователи, опираясь на значение термина в традиционном китай- ском языке, которое имеет два значения, а именно: ) весы, ) против писания, но ради принципа [wang : ]. При этом понятие всегда было связано со стратегией или тактикой, что демонстрирует продуманность и прагматизм тер- мина. Связь с первоначальным значением «весы» не утрачена в современной трактовке понятия, так подразумевает определенный баланс при использовании такого рода силы. В официальных заявлениях китайского руководства преимущественно упот- ребляется термин жуань шили (软实力), как правило в связке с прилагательным вэньхуа (文化) — культура или культурная, что фактически диктует направлен- ность «мягкой силы» государства. Китайский исследователь Пан Чжунъин выдвигает еще один емкий термин жуань гунфу (软功夫) (мягкое мастерство/усилие), оно достигается только тогда, когда другие страны восхищаются и стремятся догнать и перегнать в некоторых цивилизационных аспектах страну-субъект [pang zhongying : ]. Фактически этот навык позволяет стать примером для других и заставить всех равняться на се- бя, хотя бы по ряду параметров. Впервые понятие «мягкой силы» стало разрабатываться американским по- литологом Джозефом Найем еще в -х гг., в основном применялось к политике США. Некоторые отдают «пальму первенства» в разработке концепции «мягкой силы» другим американским политологам. Китайский профессор Лю Цзайци счи- тает, что предшественником Ная был Р.С. Клайн, выдвинувший формулу сово- купной мощи государства. Согласно его теории основные элементы этой форму- лы можно разделить на материальные и духовные, последние, по мнению Лю Цзайци, и представляют собой «мягкую силу» [Лю : ]. На настоящий момент научным сообществом выработано немало определе- ний политики «мягкой силы», которые в основном повторяют и дополняют кон- цепцию Дж. Ная. Концепция «хорошо прижилась» не только в западной науке, но и нашла свое применение на востоке, в том числе в Китае. Большинство ис- следователей заговорило об угасающей «мягкой силе» США и возрастающей китайской. Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой Понятие, введенное Наем, было отнюдь не новым для Китая, практика мир- ного достижения политических целей всегда использовалась в этой стране. Мно- гие китайские исследователи считают, что понятие «мягкой силы» соотносимо с высказываниями Сунь-цзы о победе над врагом без боя, а также с категорией древнекитайского философа Мэн-цзы «путь государя» (王道), под которой под- разумевалось гуманное правление и которая противопоставлялась категории «путь гегемона» (霸道), основанная фактически на «жесткой силе» [wang, lu : ]. Профессор МГУ В.М. Капицын и вовсе полагает, что образ «мягкой силы» берет истоки из восточных учений, в том числе из даосизма [Капицын : ]. СПОСОБНОСТЬ ИЛИ МУДРОСТЬ? Стоит выделить ряд определений «мягкой силы». В первую очередь вернемся к первоначальному варианту, предложенному Дж. Наем. За последние лет Най дал два определения выработанному термину. Первое было применено в г. и звучало как «способность получать то, чего ты хочешь, за счет привлекательности, а не принуждения или выплат» [nye ]. Ключевым понятием стала именно привлекательность, которое нашло свое от- ражение и в дефиниции г. В своей работе “the future of power” Най называет «мягкой силой» «способность влиять на других с помощью средств кооптации, формируя повестку дня, убеждая и вызывая положительную привлекательность с целью достижения предпочтительных результатов» [nye ]. Т.е. условно один субъект должен стать привлекательным для объекта, понравиться, что в свою очередь позволит использовать благосклонное расположение объекта в свою пользу. Среди российских авторов к трактовке Ная наиболее близки Н.В. Кухаренко и С.В. Кухаренко. По их мнению, «мягкая сила — это совокупность невоенных, дипломатических мер в отношении других государств с целью формирования привлекательного образа своей страны и расширения сферы своего влияния» [Кухаренко, Кухаренко : ]. Профессор НИУ ВШЭ М.В. Ларионова выдвигает другое определение, осно- ванное на термине «положительное восприятие». Таким образом, автор уходит от связки «мягкая сила» = привлекательность. ««Мягкая сила» — это способность влиять на другие государства с целью реализации собственных целей через со- трудничество в определенных сферах, направленное на убеждение и формирова- ние положительного восприятия». Стоит заметить, что определение М.В. Ларио- новой близко к концепции формирования благоприятного имиджа государства, нежели к теории об обладании неким очарованием для объектов воздействия. По мнению Д.В. Мосякова, мягкая сила — это «атрибут экспансионисткой политики», которая, в свою очередь, «с большой вероятностью будет привлека- Ларионова М.В. «Мягкая сила» — ресурс внешней политики. Электронный ресурс. Адрес доступа: http://goo.gl/wfudx (дата обращения: . . ) [larionova m.v. «myagkaya sila» — resurs vneshnei politiki. [“soft power” as a resource of foreign policy] available at: http://goo.gl/wfudx (accessed: . . )], Вестник РУДН, серия Международные отношения, март , том , № тельной и результативной, если будет базироваться на распространении и при- нятии общих ценностей, культурных и моральных идеалах» [Мосяков : ]. Таким образом, автор рассматривает «мягкую силу» как агрессивную, продуман- ную государственную стратегию продвижения своих интересов в регионе/стра- не-объекте. Китайские исследователи подходят несколько иначе к определению «мяг- кой силы». Лю Цзайци дает довольно абстрактное определение, ««мягкая сила» пред- ставляет собой мудрость и стратегию государства в развитии и использовании «твердой силы»» [Лю : ], то есть рассматривает ее вкупе с «жесткой си- лой», которая является основой, а направляющей силой выступает как раз «мяг- кая». Аналогичного подхода придерживается китайский исследователь Лю Гофу, он полагает, что источником «мягкой силы» является как раз «жесткая сила», и если жесткая — это начало всех начал, то мягкая — это всего лишь ее расширен- ная версия [Лю Гофу : ]. Это подтверждает и Ши Иньхун, заявляя, что стратегия «возвышения Китая» строится именно на двух началах: жесткой и мяг- кой силе [shi yinhong : ]. Такого рода трактовки понятия отражает китай- ский традиционный подход к дихотомии, где наличие противоположностей поддерживает баланс всего мироздания. Член Шанхайской академии общественных наук, исследователь Юй Синь- тянь считает, что «мягкая сила — это отражение влияния национальной культу- ры в международных отношениях» [yu ], уделяя особое внимание именно культурному аспекту. Тайваньские исследователи несколько отошли от традиционной терминоло- гии и вместо «мягкой силы» выделили «ассимилирующую силу» (co-optive power), элементами которой являются культура, политическая система, открытость ин- формационного сообщества, образование, идеология, экономические модели, экономическая конкурентоспособность, инновации в области it, иностранные инвестиции и гуманитарная помощь [wang, lu : ]. Это несколько соотно- сится со вторым определением «мягкой силы» Дж. Ная и говорит о ее ассими- лирующем эффекте. В целом при определении роли и места китайской «мягкой силы» довольно часто приводят сравнение с американской, что наложило определенный отпечаток на саму концепцию и на ее применение. Это подтверждает мнение одного из ве- дущих исследователей КНР в области международных отношений Пан Чжунъина, полагающего, что китайские исследователи начали исследовать «мягкую силу» только для того, чтобы лучше изучить США, которые взяли на вооружение эту концепцию на тот момент . В итоге это привело к тому, что китайское научное сообщество забыло о собственной китайской традиционной политике «умиро- pang zhongying: zhongguo waijiao, huanrou bijiao ruanshili geng kaopu [pang zhongying: chinese diplomacy, “appeasement” is more reliable than the soft power] available at: - - //http://opinion.huanqiu.com/opinion_world/ - / .html (accessed . . ) (in chinese). Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой творения», с которой «мягкая сила» в американском понимании не сравнится, и сам Китай подвергся влиянию американской «мягкой силы», приняв концепцию на вооружение в упрощенном варианте, скопировав ее . Интерпретаций «мягкой силы» немало, но тем не менее все они сводятся в ос- новном к следующему постулату: субъект международных отношений посредст- вом ненасильственных мер добивается доброжелательного расположения объекта, что в свою очередь позволяет ему влиять на деятельность объекта и приносит желаемые результаты. КУЛЬТУРНО ЦИВИЛИЗАЦИОННЫЙ vs ПОЛИТОЛОГИЧЕСКИЙ ПОДХОД И если в определениях «мягкой силы» можно найти общие черты, то меха- низм действия и ее применения у всех исследователей совершенно разный. В первую очередь стоит выделить вопрос о свойствах «мягкой силы». Тради- ционно при разделении силы на мягкую и жесткую одними из них выступают материальность и нематериальность. Большинство исследователей считают поня- тие нематериальным, и даже духовным. Среди них Юй Синьтянь, которая харак- теризует «мягкую силу» как нематериальную, и, например, экономический фактор относит к материальной, а, следовательно, «жесткой силе» [yu ]. Но, как уже было отмечено ранее, сами термины, используемые в том числе китайскими ис- следователями, отражают скорее материальность «мягкой силы», нежели немате- риальность. К тому же некоторые из них, используя количественные методы, пытаются высчитать масштаб «мягкой силы», переводя, казалось бы, нематериаль- ное понятие в конкретные цифры [Радиков, Лексютина : ]. Ввиду этого вопрос о нематериальности и материальности «мягкой силы» остается открытым и спорным, скорее всего здесь срабатывает тот же самый принцип, что с «жесткий» vs «мягкий», понятие имеет двоякие свойства, как материальные, так и немате- риальные. Британский ученый В. Кэлэхэн вводит термин «negative soft power», который можно дословно перевести как «негативная мягкая сила», но это отнюдь не гово- рит об отрицательном эффекте, который она создает, а скорее о базе, на которой строится. Как правило, это какие-либо негативные факты и эмоции, которые по- зволяют положительным для субъекта образом повлиять на объект. Так, он отмечает, что оптимизм современной концепции «китайской мечты», которая фактически является новым уровнем развития «мягкой силы» Китая, «опи- рается на пессимизм кошмара о национальном унижении» [callahan : ]. Имеется в виду постоянное упоминание о довольно низком положении Китая в системе международных отношений на протяжении xix—xx вв. В концепции Ная «мягкая сила» также не всегда имеет под собой добрые на- мерения. К «мягкой силе» относится и пропаганда, а «скручивать умы не лучше, чем скручивать запястья», считает исследователь [nye : ]. Там же. Вестник РУДН, серия Международные отношения, март , том , № Далее возникает проблема определения наполнения «мягкой силы», как пра- вило, в западной или российской историографии в этой связи встречаются слова элементы, составляющие, источники и пр., в результате в один ряд встают со- вершенно не равнозначные по функциям понятия. Согласно оригинальной концепции ключевыми источниками «мягкой силы» являются культура, политические ценности и внешняя политика . Последовав примеру Дж. Ная, многие исследователи в «центр угла» стали ставить именно культурную составляющую как основной элемент «мягкой силы» и ее движущий инструмент. В Китае, где концепция Ная хорошо вписалась во внешнеполити- ческий курс, научное сообщество даже разделилось на два лагеря: одни поддер- живали точку зрения, что «мягкая сила» строится исключительно на националь- ной культуре и ее ценностях, другие же искали другие источники «мягкой силы». Б.С. Глэйзер и М.Э. Мерфи выделили два этапа формирования китайской концепции «мягкой силы». . -е годы xx в. — преобладание концепции «мягкой силы» на основе культурного подхода. . -е гг. xxi в. — разработка концепции «мягкой силы с китайской спе- цификой», основанной на политологическом подходе [glaser, murphy : ]. Несмотря на это, и на современном этапе большинство китайских исследова- телей придерживается первой концепции: культура — это главный аспект «мягкой силы», и именно конкуренция в этой области является основной составляющей международной конкуренции [wang, lu : ]. Основоположником этой кон- цепции в КНР считается директор Бюро исследований политики ЦК профессор Ван Хунин. Он отмечает, что в вопросе государственной мощи особое внимание следует уделять именно роли культуры [wang hongning : ]. Хотя понятие культуры также весьма обширно и отличается от традиционного: в понимании Ван Хунина, она включает в себя факторы политической системы, национальной культуры и колорита, экономической системы, процесса исторического развития и наследия, идеологии, научно-технический фактор и др. [wang hongning : ]. Таким образом, культура, согласно концепции Ван Хунина, как основа госу- дарственной силы представляет собой комплексное понятие, которое скорее близ- ко к цивилизационному подходу А. Тойнби и С. Хантингтона, нежели к упро- щенному понимаю культуры. Элементы цивилизационного подхода находит и М.Л. Титаренко, который отмечает, что подход к «мягкой силе», в основе кото- рой лежит культура, «соответствует духу китайской традиции, в которой сози- дательное цивилизационное начало вэнь (文) стояло выше разрушительной во- инственности у （武)» [Титаренко : ]. Среди сторонников этой концепции член Шанхайской академии обществен- ных наук Юй Синьтянь, которая считает, что основным содержанием политики «мягкой силы» являются три составляющие: ) идеи, мышление, принципы (как государственные, так и народные), ) система (как построение международной nye joseph s. think again: soft power. available at: http://foreignpolicy.com/ / / / think-again-soft-power (accessed: . . ). Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой системы, так и государственной), ) стратегия и политика (как государственная, так и народная, а также предприятий, неправительственных организаций и др.) [Юй ]. Ван Хунъин и Лу Ечун продолжают поддерживать и развивать концепцию коллег, выделяя три основных источника китайской «мягкой силы»: китайскую культуру, китайскую модель развития, а также китайскую мирную и независимую внешнюю политику [wang, lu : ]. Именно культурно-цивилизационная концепция легла в основу национальной политики «мягкой силы», провозглашенной в г. на xvii съезде. Китай стре- мится создать и продвигать свою культурную идентичность, которая будет отве- чать современным тенденциям и спросу. Ввиду преемственности во внутренней и внешней политике китайского государства руководство КНР продолжает отда- вать центральное место в системе «мягкой силы» именно культуре, в выступле- ниях лидера пятого поколения Си Цзиньпина понятие также употребляется в связке с прилагательным «культурная», хотя таким образом выделяется только конкретная область применения, а не его центральное ядро. «Повышая государст- венную культурную мягкую силу, необходимо старательно демонстрировать самобытную притягательность китайской культуры», — заявил Си Цзиньпин октября г. во время -й коллективной учебы Политбюро ЦК КПК . Видимо, основываясь на понятии «культура», многие российские исследова- тели видят в качестве ключевого элемента «мягкой силы» «гуманитарные ини- циативы», включая культурные, образовательные и туристические [Кухаренко, Кухаренко : ]. По их мнению, Китай сделал ставку на традиции своей цивилизации и культуры, нежели на современных трендах, которые более при- сущи «мягкой силе» США [Борох, Ломанов : ]. При пропаганде своих ценностей Китай опирается на все области, включая традиционную китайскую философию, медицину, кухню, боевые искусства и т.д. [Кухаренко, Кухаренко : ]. По мнению М.Л. Титаренко, китайская «мягкая сила» и дальше будет «опи- раться на традиционную культуру и историческую память народа» [Титаренко : ]. Ключевую роль в политике «мягкой силы» зачастую отдают центрам распространения языка и культуры субъектов мягкой силы, включая Институты Конфуция. Не все китайские исследователи поддерживают культурно-цивилизационный подход. Лю Гофу считает, что научное сообщество почти не уделяет внимания «дипломатической мягкой силе» и «мягкой силе ценностей», а также «мягкой силе национальной идентичности» [Лю Гофу : ]. Как представитель юри- дических наук, особое место он отводит правовым нормам в системе «мягкой силы». Автор полагает, что многие западные исследователи отмечают слабость xi jinping tan guojia wenhua ruanshili: zengqiang zuo zhongguoren de huaqi he diqi. [xi jinping speech on national cultural soft power: strengthen chinese people’sbackbone and clout] avail- able at: http://news.xinhuanet.com/politics/ - / /c_ .htm (accessed . . ) (in chinese). Вестник РУДН, серия Международные отношения, март , том , № привлекательности современной государственной системы Китая, ввиду этого не- обходимо совершенствовать правовые нормы, дабы усилить «мягкую силу» в этой плоскости. Ярким представителем политологического подхода в отношении понятия «мягкой силы» является профессор Университета Цинхуа Янь Сюэтун. Согласно его видению, «мягкая сила» представляет собой сочетание международной при- влекательности, международной и государственной сил мобилизации [yan xuetong : ]. В свою очередь, они также делятся на составляющие элементы; меж- дународная привлекательность складывается из привлекательности государст- венной модели и привлекательности культуры; международная сила мобилизации подразумевает принятие предложений и требований государства-субъекта другими странами, при чем при воздействии ненасильственного влияния и состоит из стра- тегических добрых отношений и права установления международных правил. Государственная мобилизационная сила включается в себя скорее два уровня, не- жели элемента: сила мобилизации в отношении верхнего класса общества и сила мобилизации в отношении низшего класса общества [yan xuetong : ]. Поли- толог из КНР считает, что «мягкая сила» Китая включает в себя культурную и по- литическую силу, но основу составляет именно вторая [yan xuetong : ]. При этом в своей работе Янь Сюэтун и Сюй Цзинь «Сравнение мягкой силы Китая и США» приводят формулу расчета «мягкой силы», используя количест- венные показатели, доказывая, что «мягкая сила» США в три раза превосходит китайскую. Спорной составляющей в концепции «мягкой силы» остается экономика. По мнению Дж. Ная, довольно сложно определить, какая часть экономических от- ношений относится к «мягкой», а какая к «жесткой силе» [nye : ]. «Эко- номические ресурсы могут стать источником как жесткой, так и мягкой силы. Они могут быть использованы как для привлечения, так и для принуждения» . Тем не менее, успешная экономическая модель безусловно обладает при- влекательностью не только на межгосударственном уровне, но и в рамках миро- вого сообщества. Наличие фактора успешного экономического развития, как часть «мягкой силы» КНР, прослеживается и в теории «Пекинского консенсуса», кото- рый противопоставляется «Вашингтонскому консенсусу» [ramo ]. Американ- ский политолог Дж. Курланцик считает, что независимо от того, как называть феномен «Пекинского консенсуса», Китай определенно активно продвигает за ру- беж свою социально-экономическую модель развития [kurlantzick : ]. Представители Санкт-Петербургского государственного университета И.В. Ра- диков и Я.В. Лексютина также особое внимание уделяют экономическому факто- ру «мягкой силы», соглашаясь отчасти с Дж. Наем, что экономические санкции и давление могут быть причислены к «жесткой силе», но утверждая, что «успеш- ная модель экономического развития способна оказывать магнетическое влияние на другие и, прежде всего, развивающиеся государства» [Радиков, Лексютина nye joseph s. think again: soft power. available at: http://foreignpolicy.com/ / / /think- again-soft-power (accessed: . . ). Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой : ]. Более того, авторы приходят к выводу, что ресурсом «мягкой силы» может выступать не только успешная реализованная экономическая модель, но и даже ожидаемые «перспективы ее развития» [Радиков, Лексютина : ]. «Экономический взлет» рассматривается как источник «мягкой силы» КНР и М.Л. Титаренко, который полагает, что многие развивающиеся страны пытаются перенять передовой опыт Пекина в этой области [Титаренко : ]. Несколько иначе объясняет Чжао Лэй роль экономической мощи Китая в по- литике «мягкой силы». Он полагает, что «возросшая экономическая мощь запус- тила процесс восстановления и укрепления веры народа в собственные силы и вер- нула китайскую традиционную систему культурных ценностей» , т.е. стала своего рода рычагом наращивания «мягкой силы» в общепринятом понимании. И не- смотря на то, что китайский исследователь также отдает предпочтение культуре как ядру мягкой силы, он отмечает ряд недостатков в этой области, в частности: «различие в культурном и политическом диалогах между Китаем и остальным миром», что не позволяет сформировать общую ценностную базу, как в случае с экономическими отношениями . Пан Чжунъин, говоря о государственной мощи, выделяет три силы: военную, мягкую силу и экономику [pang zhongying : ], разделяя понятия «мягкой силы» и экономики. Выделяются и другие составляющие «мягкой силы»: правительство, образо- вание, дипломатия, коммерческая деятельность и инновации [the new persuaders]. Российский исследователь С.В. Михневич выделяет семь направлений «мяг- кой силы» КНР, в том числе: ) «распространение и популяризация языка; ) продвижение традиционной и современной культуры; ) расширение образовательных контактов; ) развитие экономических связей и научно-техническое сотрудничество; ) содействие международному развитию; ) развитие общественной дипломатии; ) поддержка соотечественников» [Михневич : ]. Хотя возможно проследить явную взаимосвязь первого и третьего направ- ления, при этом «расширение образовательных контактов» скорее говорит о soft power trade, а не конкретно о китайской «мягкой силе». Среди основных прояв- лений мягкой силы КНР в российской науке также выделяется распространение СМИ на национальных языках, «фасадная политика» и др. [Кухаренко, Кухаренко : ]. Зарубежные исследователи также определяют ряд весьма характерных инст- рументов «мягкой силы»: инвестиции, гуманитарная помощь, программы обмена, дипломатия и участие в многосторонних институтах [zheng : ]. Политолог Д. Шэмбо и вовсе полагает, что ключевым инструментом «мягкой силы» КНР являются деньги, а к проектам китайской «мягкой силы» относятся такие новые ibid. ibid Вестник РУДН, серия Международные отношения, март , том , № инициативы, как Азиатский банк инфраструктурных инвестиций, Экономический пояс Шелкового пути и др. Довольно спорным нематериальным элементом «мягкой силы» выступает религия, которую Най называет не иначе как «обоюдоострый меч», и ситуация полностью зависит от того, кто этот меч держит [nye : ]. Влияние рели- гии на международные отношения ощутимо заметно в последние десятилетия, но присутствовало оно всегда: и во времена Крестовых походов, и xxi в. Неко- торые исследователи выделяют ее в качестве отдельной категории источников «мягкой силы», с другой стороны, религию можно рассматривать вкупе с нацио- нальной культурой государства. Хотя в китайской истории именно религия по- рой выступала в качестве основного элемента «мягкой силы» [Кабанова ]. В качестве нематериальных инструментов «мягкой силы» КНР выделяют также «национальную сплоченность» и законность режима. Российские исследователи И.В. Радиков и Я.В. Лексютина выстраивают свою систему «мягкой силы». Согласно их видению, центральным ядром «мягкой силы» служат идеология и институты, в свою очередь проводником — массовая культура и информационные технологии, в качестве инструментов авторы называют «ком- муникацию, и особенно Интернет, НПО, дипломатические представительства, культурные, научные и образовательные центры, крупномасштабные мероприя- тия», а носителями — известные торговые марки, достижения в науке, технике, искусстве и даже мода» [Радиков, Лексютина : ]. При этом ими весьма кри- тично оценивается роль массовой культуры как основного проявления «мягкой силы». Авторы отмечают, что в мире существенно усилился антиамериканизм, что свидетельствует об ослаблении «мягкой силы» США, хотя американская куль- тура по-прежнему популярна и не теряет своих позиций. *** Сформировавшаяся концепция «мягкой силы» хорошо вписалась во внешне- политическую стратегию «мирного возвышения и мирного развития» КНР, а позже идею построения «гармоничного мира». Понятие продолжает превалировать в за- явлениях лидеров страны и их внутренней и внешней политике, постепенно услож- няясь и приобретая многоуровневость. В результате анализа вышеизложенных теорий и концепций можно заклю- чить, что на данный момент не сложилось единого мнения касательно системы «мягкой силы». «Мягкая сила» различных стран отличается друг от друга, одни ак- тивно используют «культуру и исторически успешные традиции», другие — свою социальную или экономическую модель развития [pang zhongying : ]. Ве- роятно, поэтому не пока нет единой концепции, но в таком случае возникает во- прос: если речь идет о «мягкой силе» конкретной страны, например, о Китае, почему снова нет единообразия? Профессор МГИМО М.М. Лебедева справедливо замечает, что не может быть универсальной концепции привлекательности ввиду неоднородности общества, shambaugh david. china’s soft-power push. available at: https://www.foreignaffairs.com/ articles/china/ - - /china-s-soft-power-push (accessed . . ). Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой и «то, что одним кажется привлекательным, необязательно будет привлекательным для других» [Лебедева]. Следовательно, на настоящий момент остается открытым вопрос об определении привлекательности «мягкой силы» каждого субъекта, вклю- чая КНР, а также ее ключевых составляющих. Большинство исследователей придерживается мнения, что именно культура лежит в основе «мягкой силы» КНР, отчасти исходя из официальной позиции Пе- кина, хотя попытки найти альтернативный подход также существуют. К «мягкой силе» зачастую относят различные элементы, которые олицетворяют собой мир- ную деятельность и сотрудничество. Но, как отмечает Ш. Бреслин: «комбиниро- вание многочисленных невоенных элементов в рамках одного понятия „мягкий“ вряд ли позволит понять нюансы различных типологий и источников силы» [breslin : ]. СПИСОК ЛИТЕРАТУРЫ [ ] Борох О.Н., Ломанов А.В. От «мягкой силы» к «культурному могуществу» // Россия в глобальной политике. . Т. . № . c. — . [ ] Бояркина А.В., Лыков К.Ф., Печерица В.Ф. Превентивная дипломатия как инструмент «мягкой силы» КНР // Вестник ЗабГУ. . № ( ). c. — . [ ] Журавлева (Кабанова) Е.А. Методы управления приграничными народами Китая в xviii в. // История, политика и философия в эпоху глобализации. . c. — . [ ] Капицын В.М. Космополитизм-компонент мягкой силы и глобального управления // Обозреватель-observer. . № . c. — . [ ] Кухаренко Н.В., Кухаренко С.В. Институты Конфуция как инструмент политики «мягкой силы» КНР // Современный Китай и его окружение. М.: КРАСАНД, . [ ] Кухаренко Н.В., Кухаренко С.В. Образование как инструмент «мягкой силы» Китая в от- ношении России // Современный Китай в системе международных отношений. М.: Книж- ный дом «ЛИБРОКОМ», . [ ] Лебедева М.М. «Мягкая сила» в отношении Центральной Азии: участники и их действия // Вестник МГИМО-Университета. . № ( ). c. — . url: http://cyberleninka.ru/ article/n/myagkaya-sila-v-otnoshenii-tsentralnoy-azii-uchastniki-i-ih-deystviya (дата обраще- ния: . . ). [ ] Лю Цзайци «Мягкая сила» в стратегии развития Китая // Полис. Политические исследо- вания. . № . С. — . [ ] Михневич С.В. Панда на службе Дракона: основные направления и механизмы политики «мягкой силы» Китая // Вестник международных организаций. . Т. . № . С. — . [ ] Мосяков Д.В. «Мягкая сила» в политике Китая в Юго-Восточной Азии // Юго-Восточная Азия: актуальные проблемы развития. . Т. . С. — . [ ] Радиков И.В., Лексютина Я.В. «Мягкая сила» как современный атрибут великой дер- жавы // Мировая экономика и международные отношения. . № . c. — . [ ] Титаренко М.Л. «Мягкая сила» в отношениях Китая с внешним миром. М.: ИДВ РАН, . [ ] breslin sh. the soft notion of china’s ‘soft power’, chatham house. asia programme paper: asp pp / . february . [ ] callahan w.a. identity and security in china: the negative soft power of the china dream // politics. . vol. ( — ). p. — . [ ] glaser b.s., murphy m.e. soft power with chinese characteristics. the ongoing debate // chinese soft power and its implications for the united states. competition and cooperation in the developing world. a report of the csis smart power initiative. center for strategic Вестник РУДН, серия Международные отношения, март , том , № and international studies, . p. . url: http://csis.org/files/media/csis/pubs/ _ mcgiffert_chinesesoftpower_web.pdf (дата обращения: . . ). [ ] kurlantzick j. charm offensive: how china’s soft power is transforming the world. yale uni- versity press, . [ ] liu gofu zhongguo ruanshili fazhan mianlin de tiaozhan he yingdui: yi fazhi jianshe wei shijiao // shehui kexue qianyu. [china's soft power development challenges and response: perspective of creation of the rule of law //social science frontier]. . no. . p. — (in chinese). [ ] nye joseph s. soft power: the means to success in world politics. new york: public affairs, . [ ] nye joseph s. the future of power. new york: public affairs, . p. — . [ ] pang zhongying guojiguaxi zhongruanliliang ji qita — ping meiguo xuezhe yuesefu nai de «zhuding lindao» // zhanlue yu guanli. [soft power and other in international relations-talking about joseph nye «bound to lead» // strategy and management]. . vol. . p. — (in chinese). [ ] ramo j.c. the beijing consensus. london: the foreign policy centre, . [ ] the new persuaders: an international ranking of soft power. the institute for government. url: http://www.instituteforgovernment.org.uk/sites/default/files/publications/the% new% persuaders_ .pdf (дата обращения: . . ). [ ] shi yinhong zhongguo heping jueqi de zhanlue jiyu he ruogan jiben tiaojian // guoji guancha [a number of strategic opportunities and basic conditions of china's peaceful rise // international observer]. . no. (in chinese). [ ] wang hongying, lu yeh-chung the conception of soft power and its policy implica- tions: a comparative study of china and taiwan // journal of contemporary china. . no. ( ). p. — . [ ] wang huning zuowei guojia shili de wenhua: ruanquanli // fudan xuebao. [as the culture of national power: soft power // journal of fudan university]. . no. . p. — (in chinese). [ ] wang yiwei public diplomacy and the rise of chinese soft power // annals. . p. — . [ ] yan xuetong, xu jin zhongmei ruanshili bijiao // xiandai guoji guanxi. [comparison of chi- nese and american soft power. contemporary international relations]. . no. . p. — (in chinese). [ ] yan xuetong ancient chinese thought, modern chinese power. princeton university press, . [ ] yu xintian ruanshili jianshe yu duiwai zhanlue // guoji wenti yanjiu [soft power construction and external strategy of china. international studies]. . no. . url: http://www.aisixiang.com/ data/ .html (in chinese). [ ] zheng d.e. Сhina’s use of soft power in the developing world strategic intentions and impli- cations for the united states. chinese so power and its implications for the united states: competition and cooperation in the developing world, a report of the csis smart power initiative. center for strategic and international studies, washington, d.c., march . Дата поступления статьи: . . Благодарности: Данная статья подготовлена в рамках НИР РУДН г. «Незападные теории международных отношений. Азиатские, латиноамериканские и африканские концепции мироустройства» Для цитирования: Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой // Вестник Российского университета дружбы народов. Серия «Международные отношения». . № . С. — . Журавлева Е.В. Стратагема красотки: теории «мягкой силы» с китайской спецификой the beauty trap: the theories of “soft power” with chinese characteristics e.v. zhuravleva department of theory and history of international relations peoples’ friendship university of russia miklukho-maclay st., / , moscow, russia, currently there are a lot of definitions and conceptions of “soft power” in the world’s scientific literature. the english-language works mainly adopted the term “soft power”, terminology is also va- ried in chinese historiography: “ruan shili”, “ruan liliang” and “ruan quanli” (软实力, 软力量 and 软权力). a variety of terms is reflected in the variety of interpretations of the system or mechanis- mof “soft power”, that allows us to conclude that at the moment there is noformed unified vision and approach to its study. the subject of this study is the russian and foreign theories of “soft power” in relation to china's foreign policy. the author raised a number of tasks, among which are: to determine the place a policy of “soft power” in the foreign policy of china, to analyze the existing interpretation of the concept of “soft power with chinese characteristics”, as well as trace the development of theories of “soft power”. as a result of the research the author comes to the conclusion that despite the difference in in- terpretations, there are a lot of common aspects, including the idea of the majority of researchers that the concept is directly related to the influence of the subject to the object, and that the main in- struments of “soft power” are humanitarian cooperation, investment, dialogue at the highest level, and others. but the combination of numerous non-military elements within the same term “soft power” doesn’t form a unified, approved concept. different countries have their own unique system of soft power, and its instruments, key elements and basic principles are not the same. for example, talking about “attractiveness” applied to chinese soft power, we can conclude, that it is only the tip of the iceberg. this study allows not only to form an idea of the “soft power” through the prism of various scientific researches, but also to identify the key elements of the system, as well as alternative ways of applying the policy of “soft power” and options for its increase. key words: theory of “soft power”, china's foreign policy, comprehensive state power, chi- na’s rise. references [ ] borokh o.n., lomanov a.v., . ot «myagkoi sily» k «kul'turnomu mogushchestvu» [from “soft power” to the “cultural might”]. rossiya v global'noi politike. vol. . no. . p. — . 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(march ). pp. — . a swing of beauty: pendulums, fluids, forces, and computers fluids article a swing of beauty: pendulums, fluids, forces, and computers michael mongelli and nicholas a. battista ,* department of computer science, pennington road, the college of new jersey, ewing township, nj , usa; mongelm @tcnj.edu department of mathematics and statistics, pennington road, the college of new jersey, ewing township, nj , usa * correspondence: battistn@tcnj.edu; tel.: + - - - received: january ; accepted: april ; published: april �� abstract: while pendulums have been around for millennia and have even managed to swing their way into undergraduate curricula, they still offer a breadth of complex dynamics to which some has still yet to have been untapped. to probe into the dynamics, we developed a computational fluid dynamics (cfd) model of a pendulum using the open-source fluid-structure interaction (fsi) software, ib d. beyond analyzing the angular displacements, speeds, and forces attained from the fsi model alone, we compared its dynamics to the canonical damped pendulum ordinary differential equation (ode) model that is familiar to students. we only observed qualitative agreement after a few oscillation cycles, suggesting that there is enhanced fluid drag during our setup’s initial swing, not captured by the ode’s linearly-proportional-velocity damping term, which arises from the stokes drag law. moreover, we were also able to investigate what otherwise could not have been explored using the ode model, that is, the fluid’s response to a swinging pendulum—the system’s underlying fluid dynamics. keywords: fluid dynamics education; damped pendulums; fluid drag; fluid-structure interaction; computational fluid dynamics . introduction historically, pendulums have been used for a multitude of purposes. from seismometers used almost two thousand years ago [ , ], to devices that increase efficiency for societal capacity, such as reciprocating saws and pumps [ , ], to keeping time [ , ], to even medieval torture devices [ ], applications of pendulums are far and wide. edgar allan poe even wrote a short story about one, the pit and the pendulum [ ]. the esteemed polymath galileo galilei dreamt of the first pendulum clock in , but it wasn’t constructed until when dutch physicist christiaan huygens drew out the plans, thus designing it. he enlisted clockmaker salomon coster to build it. the introduction of a pendulum clock increased time keeping accuracy from minutes to a quarter of minute [ ]— pendulums changed history! it is no surprise that the study of pendulums swings its way into many foundational courses in science, mathematics, and engineering. students are introduced to them in courses such as mechanics, dynamics, or differential equations, where they are first exposed to the idea of a simple gravity pendulum. a simple gravity pendulum is an idealized pendulum—a weight (bob) is attached to a massless string, which is tethered to a fixed pivot point, and is allowed to swing freely, without friction [ ]. it will continue to swing forever. realistic? not unless one lives in a vacuum, but ultimately a good place to begin a student’s exploration of simple harmonic motion. fluids , , ; doi: . /fluids www.mdpi.com/journal/fluids http://www.mdpi.com/journal/fluids http://www.mdpi.com https://orcid.org/ - - - http://www.mdpi.com/ - / / / ?type=check_update&version= http://dx.doi.org/ . /fluids http://www.mdpi.com/journal/fluids fluids , , of if θ(t) represents the angular displacement (in radians) from the vertical at time t (see figure a), the ordinary differential equation (ode) describing such a simple pendulum system takes the form: i d θ dt + mgl sin θ = , ( ) where i, m, and l are the pendulum bob’s moment of inertia and overall mass and length, respectively, and g is the gravitational acceleration. since the only external force acting on this pendulum is gravity, it will swing forever, with no loss in oscillatory amplitude, see figure b for an example. figure b shows simulated results for different pendulum cases, each with a circular bob of a different radius. note that the ode was solved numerically, as no small angle approximation was used [ ]. for these cases of circular bobs, of radius r, attached to a massless string of length l, the moment of inertia is calculated to be: i = m r + ml . ( ) there are two things to note from figure b. the first is that over time the oscillation amplitudes do not decay. the second is that although amplitudes of oscillation are not affected, the period of oscillation is affected by bobs of different radii. larger bobs have larger periods, due to their moment of inertia being greater [ ]. figure . (a) a pendulum of length l with circular bob of radius, r, and mass, m. (b) angular displacement (in radians) over time for various gravity pendulums of differing radii. the non-dimensional time is given in terms of the number of periods of the case with radius, r. in a world (or classroom) like ours which does not exist in a vacuum, a table-sized pendulum demonstration would eventually lead to its angular oscillations reaching zero, i.e., standing still. this is due to the pendulum swinging in air—a fluid. the air resists the pendulum’s motion, effectively pushing back on the pendulum. this is known as fluid drag. the concept of fluid drag is probably familiar to you already. it is the reason why parachutes work. the equation governing a pendulum swinging in a fluid environment is given by i d θ dt + b dθ dt + mgl sin θ = , ( ) where the parameter b is deemed a damping parameter. this is a reduced order model of the system, as the contribution of the fluid onto the pendulum is entirely contained within the parameter, b. that is, this equation models how the fluid is believed to affect the swinging motion of the pendulum, while providing no mechanism to understand the underlying fluid’s dynamics. numerical simulation results from solving equation ( ) are presented in figure . fluids , , of figure . angular displacements against non-dimensional time for damped physical pendulums in the case of (a) constant radius and varied damping, b, and (b) constant b and varied radii. figure a holds the radius constant at r, the same r from figure b, while varying the damping coefficient, b. compared to figure b, angular oscillations decay in all cases when b > . the damping induced from b > will eventually lead to its equilibrium—a stationary pendulum hanging straight down. however, the decay rate is dependent on b; larger values of b lead to a quicker decay of oscillation. note that b has units of kg·m s and in realistic situations, b > . moreover, depending on the value of b, the pendulum system will exhibit one of three behaviorial cases: . under-damped: the pendulum will swing back and forth, although its amplitude of oscillation will steadily decline, until it asymptotically approaches its equilibrium. . critically-damped: the pendulum returns to equilibrium as quickly as it can. if the damping parameter were made slightly more or slightly less, it would result in the pendulum returning slower to its equilibrium position. . over-damped: the pendulum moves towards its equilibrium position slower than the critically-damped case. there is no oscillation. the simulations shown in figure b held the damping parameter fixed (b = from figure a) and varied the radius of the bob. note that changing the radius r will vary the moment of inertia (see equation ( )). this data suggests that as r increases for a given b, this would lead to more oscillatory behavior. that is, smaller r tends to make the pendulum system more damped. intuitively this doesn’t make much sense as is—a larger pendulum bob should feel more drag since it has a larger surface area. it would be like jumping out of an airplane with a parachute with a surface area of m and floating down slower (and more softly) than a parachute of m . how could this be? for the simulations in figure b, we fixed the damping parameter b and then varied r. we did not consider that the damping parameter may depend on the radius (among a variety of other parameters), that is, the geometry of the pendulum bob. furthermore, we have yet to motivate where the damping term in equation ( ) comes from. let’s settle that. it comes from the seminal work of prolific physicist and mathematician sir george stokes, who even studied drag force using pendulums [ ]! in particular, he derived a drag force equation, now known as stokes law, by investigating spheres moving through a fluid at low reynolds numbers, i.e., situations in which either the fluid is moving extremely slowly or the fluid’s viscosity is very high [ , ]. stokes law (for a sphere at low re) is presented as the following: fd = πµrv, ( ) where fd is the fluid drag, µ is the fluid’s dynamic viscosity and r and v are radius and speed of the sphere that is moving through the fluid. note that the reynolds number (re) depends on two fluids , , of fluid parameters, i.e., its density, ρ, and dynamic viscosity, µ, as well as two parameters based on the physical system being investigated, i.e., a characteristic length and velocity scale, l and v, respectively. the re is defined to be re = ρlv µ . ( ) thus stokes drag describes that this damping frictional force acting on the sphere is proportional to its size, fd ∼ r, and speed, fd ∼ v. careful to remember that this may only be true in low reynolds number situations, where either v, r, or both may be small. notice that the form that the damping term took in equation ( ) was similar, but used angular displacement (θ(t)) and angular velocity ( dθdt ). as suggested by numerical simulations presented above, this damping equation gives rise to exponential decay in angular displacement (figure ). at higher reynolds numbers, i.e., situations in which fluid viscosity is low or the speed or size of an object is large, the drag force takes a different form. for these situations, the drag law was discovered by none other than the infamous lord rayleigh (john william strutt) using dimensional analysis [ ]. for high reynolds numbers settings, the fluid drag force takes the following form [ , ]: fd = ρr kv , ( ) where ρ is the fluid density, r is the sphere’s radius, v is the sphere’s velocity, and k is a non-dimensional number that is based on the fluid flow’s speed and direction as well as the object’s shape, size, and orientation in respect to the flow, and the fluid’s density and viscosity. in a nutshell, for a specific object, this constant k may significantly change if one or more of these parameters are varied. this drag force is traditionally represented in the following generalized manner: fd = ρ acd v , ( ) where a is a cross-sectional area of an object in flow and cd is a dimensionless number called the drag coefficient. in this representation cd is analogous to k above. moreover, work in the latter half of the th century and early st century has shown that in particular situations correction terms must be included into the drag force equations [ , ]. furthermore there are still unknown dynamics of pendulums involving small amplitude oscillations [ ]. although physical pendulums have been used for thousands of years and studied by students in foundational courses for over a century, they remain an active research area [ ]. with the advent of new technologies, e.g., experimental measurement and flow visualization tools, researchers have further probed into the complex interactions of pendulums and the fluid environments they are immersed within [ – ]. in particular, mathai et al. [ ] investigated how fluid drag on pendulums may be enhanced due to dynamic interactions with their own vortex wake as they swing—something not quantified previously! mathai et al. [ ] went on to note even with the wake history force included, the current model is still quite basic. in reality, the dynamics is highly nonlinear, with changes in direction, curvilinear trajectories and wide variations in instantaneous re . . . fully resolved direct numerical simulations. . . can provide better insights into the flow-induced forces. that is exactly where our work on pendulums began, although there have been two previous studies using cfd models of pendulums [ , ]. in this paper we implemented a fluid-structure interaction (fsi) computational model of a swinging pendulum containing a spherical bob (a circular bob in two dimensions). in our fsi model, we varied the size of the circular pendulum bob, i.e., its radius, and its mass. we then analyzed the resulting data in terms of angular displacement, speed of the pendulum bob, and fluid forces acting on it, as well as compared the dynamics between our fsi model and the canonical reduced ode model for a damped physical pendulum, equation ( ). furthermore, we visualized (and qualitatively analyzed) the fluids motion in response to a swinging pendulum. fluids , , of in addition, we provide instructor resources, such as slides and movies, in the supplemental materials, with the goal to streamline use of this work in educational settings. moreover, we also offer the science community the first open-source pendulum models in a fluid-structure interaction framework. the models can be found at github.com/nickabattista/ib d in the sub-directory: ib d → matib d → examples → examples_education→ pendulum. note that each example is of a point mass model bob and was selected for its computational speed in comparison to circular bobs (those of non-zero radius). moreover, three versions are presented, each corresponding to a different grid resolution. the least spatially resolved case, × , will be the fastest to run, but also the least accurate of the , while the × case has the highest spatial resolution, but will run the slowest. the default setting is to only save the pendulum (lagrangian) data. to store the fluid (eulerian) data, flags corresponding to the desired fluid quantities may be selected within the input d file. we also provided the scripts used to solve equations ( ) and ( ) that produce figures and . . methods to investigate the swinging motion of a two-dimensional pendulum bob immersed in a viscous, incompressible fluid, we used computational fluid dynamics (cfd). in our model, the bob starts at rest and begins to swing under gravitational acceleration acting on the mass of the pendulum. an immersed boundary (ib) framework was used to couple the pendulum’s motion and the fluid it is immersed within. scientists and engineers can use ib to study the interactions of an object and the fluid it is contained within, i.e., you can explore how the fluid affects the object and vice versa. the immersed boundary method was developed by charles peskin, a mathematical physiologist at the courant institute of mathematics [ – ]. even though ib was invented in the s, it is still extensively used for investigating fluid-structure interaction problems today. many mathematicians, engineers, and scientists have since improved the original algorithm in attempts to increase its accuracy without significantly increasing the computational expense and time required [ – ]. ib is still a leading numerical framework for studying problems in fsi due to its robustness [ , ]. it has previously been applied to study problems ranging from cardiac fluid dynamics [ – ] to aquatic locomotion [ – ] to insect flight [ – ] to dating and relationships [ ]. additional details on the ib method can be found in appendix b. in the remainder of this section we will introduce our fsi pendulum’s implementation into the ib d framework, i.e., the computational geometry, geometrical and fluid parameters, and model assumptions. . . model geometry figure presents our pendulum model’s computational geometry. in particular, figure a illustrates the modeling idea—a bob (of radius r) is composed of a central point mass (of mass m) and outer neutrally-buoyant shell layer. it is tethered to a particular fixed location, a distance l away. the pendulum is immersed in a viscous, incompressible fluid of uniform density ρ, and dynamic viscosity, µ. note that the fluid within and outside the pendulum bob is uniform in its properties. we define the pendulum’s angular displacement, θ, to be the angle from the vertical dotted line. gravity acts on the central mass point; as the rest of the pendulum bob’s geometry is neutrally-buoyant, all acceleration of the bob is due to this single gravitational interaction. however, due to the structure properties of the pendulum bob, the neutrally-buoyant shell will undergo fluid drag due to the fluid’s resistance in letting the pendulum bob move through it. github.com/nickabattista/ib d fluids , , of figure . (a) model of an immersed pendulum with circular bob of radius r in a viscous, incompressible fluid. the fluid has density and viscosity of ρ and µ, respectively. the pendulum has length l and the bob has mass m, concentrated at its center. (b) the computational geometry illustrating the fiber model construction of the discretized lagrangian mesh. as we wished to vary the pendulum bob’s radius and mass of its central point, we considered the parameters listed in table for our fsi pendulum model. the explicit radii, r, and masses, m studied are r ∈ { . , . , . , . , . , . , . , . , . , . , . } m and m ∈ { × , × , × , × , × , × } kg, respectively. the initial angular displacement, θ , was −π + π = − π radians. we did not vary properties of the fluid, neither its density nor viscosity. note that the kinematic viscosity in our simulations was ν = µρ = − m /s. some common liquids with kinematic viscosities around − m /s are sulphuric acid at room temperature or a variety of oils (coconut, sae motor oils, peanut, whale, etc.) at ∼ – degrees fahrenheit [ ]. kinematic viscosity, ν, measures the fluid’s internal resistance to flow under gravity. table . table of geometric and fluid parameters used in our pendulum study. parameter description value l pendulum length . m r pendulum bob’s radius r ∈ [ . , . ] m m mass m ∈ [ × , × ] kg ρ fluid density kg/m µ fluid (dynamic) viscosity . kg/(m · s) g gravitational acceleration . m/s θ initial angular displacement − π radians . . model construction figure b provides a more detailed overview of the computational geometry. in particular it provides details regarding how the structure is modeled using i b fiber models, which are used to mimic desired material properties between discretized points, i.e., lagrangian points, that compose the geometry [ ]. the single mass point is tethered to the fixed point, a distance l away, via a virtual spring. the static hinge point is tethered in place using the target point model. target points can be used to hold lagrangian points nearly rigid. the individual mass point uses a massive point model that tethers the individual lagrangian point to a mass, which dampens its movement [ ]. note that the target point and massive point models use spring-like mathematical formulations to achieve their desired effects, see [ ]. the neutrally-buoyant shell is composed of equally-spaced lagrangian points, to which are tethered to their neighboring points via virtual spring connections. furthermore, each of these lagrangian points are further tethered to the massive point in the center of the pendulum bob by a virtual spring. all of the virtual spring connections in the model use stiff springs with a particular fluids , , of spring resting length in order to keep the geometry from changing shape, i.e., trying to ensure that the lagrangian points maintain a specific distance from other points. the number of lagrangian points in a circular shell varies by the radius, see table . note that due to the coupled nature of the lagrangian structure and fluid in the standard immersed boundary framework, it was more straightforward for us to approximately model rigid structures in this manner. additional steps would have been necessary to solve the problem of each lagrangian point only being allowed to move in a constrained way, due to the imposed rigidity, under forces from the fluid and other external forces (like gravity) pushing on it. please see [ , ] for further information regarding immersed boundary formulations with rigid bodies. table . table providing number of lagrangian points in the circular shell for a particular radius, r. radius (m) . . . . . . . . . . . # lag. pts in shell fiber models use a variety of different deformation force laws to model material properties. to model virtual (hookean) springs, deformation forces were calculated as follows, fs pr = ks pr ( − rl(t) ||xa(t)− xb(t)|| ) · ( xa(t)− xb(t) ya(t)− yb(t) ) ( ) where ks pr is the spring stiffness, rl(t) is the spring’s resting lengths, and xa = 〈xa, ya〉 and xb = 〈xb, yb〉 are the lagrangian nodes tethered by the spring. note that in our model the resting lengths are time-independent, hence rl(t) = rl. as mentioned previously, the spring stiffnesses are large to ensure minimal stretching or compression of the computational geometry. the spring stiffness used to tether the massive point to the fixed hinge point and the pendulum bob points to both one another and the massive point are denoted by ks prl and ks prb , respectively. in the simple case where a preferred position is enforced, boundary points are tethered to target points via springs. its corresponding deformation force equation, which describes the force applied to the fluid by the boundary in lagrangian coordinates is given by ftarget and is explicitly written as, ftarget = ktarget (ya(t)− xa(t)) , ( ) where ktarget is the stiffness coefficient, and ya(t) is the prescribed lagrangian position of the target point. in all simulations the hinge point was held nearly rigid by applying a force proportional to the distance between the location of the actual lagrangian point and its preferred target position. using a large value of ktarget helps mitigate a small deviation between the actual and preferred position. artificial mass is modeled using the massive point approach of kim et al. [ ]. it is similar to target points. za gives the cartesian coordinates of the massive points, with associated mass density ma. note that such points do not interact with the fluid directly, similar to target points. xa(t) give the cartesian coordinates of a neutrally-buoyant lagrangian boundary point, which do interact with the fluid. similar to target points, if a lagrangian point deviates from its massive point, a restoring force drives them back together, as shown in its mathematical description below fmass = kmass(za(t)− xa(t)) ( ) ma ∂ za(t) ∂t = −fmass − ma gŷ, ( ) where kmass is a stiffness coefficient with k m � , ma is the mass of the massive point, g is the acceleration due to gravity in vertical direction, ŷ, and za(t) is the position of the massive point to which the lagrangian point, xa(t), is tethered to at time t. fluids , , of all numerical stiffness parameters are given in table . the stiffnesses were selected to be as high as possible while also maintaining stability and fidelity of our numerical solver. each pendulum simulated was of length . m and was immersed in a square computational domain of size (lx , ly) = ( m, m), with a grid resolution of × , i.e., dx = dy = lxnx = ly ny = . m. points that compose the circular pendulum bob were evenly spaced apart at a distance of ds = dx . note that this is the standard convention in the immersed boundary literature when choosing the lagrangian point spacing, ds. it is used to avoid leaky boundaries [ ]. thus, fluid will not be allowed to flow in or out of the pendulum bob, unless due to numerical error. moreover, note that the adjacent nodes along the circle were a distance r from the massive point at the center of the pendulum bob, which was tethered a distance of l from the fixed hinge target point. each of the spring connections between specific points used a spring resting length equal to such corresponding distances in an effort to maintain the geometry while the pendulum was swinging. a time-step of dt = . × − s was used to march forward in time. table . table of numerical temporal, spatial, and fiber model parameters used in our pendulum study. parameter description value dt time-step . × − s lx × ly grid size m × m (nx , ny) grid resolution ( , ) dx = dy spatial step lx /nx = ly /ny = . m ds lagrangian point spacing ∼ lx nx ks prl spring stiffness coefficient (mass to hinge) . × kg · m/s ks prb spring stiffness coefficient (pendulum bob) . × kg · m/s ktarget target point stiffness coefficient × kg · m/s kmass massive point stiffness coefficient . × kg · m/s while running the simulations, we stored the following data every . s of simulation time: . position of lagrangian points . forces on each lagrangian point (horizontal/vertical and normal/tangential forces) . fluid velocity . fluid vorticity . forces spread from the lagrangian mesh onto the eulerian grid we then used the open-source software visit [ ], created and maintained by lawrence livermore national laboratory for visualization, see figure , and the data analysis package software within ib d [ ] for data analysis. figure provides a visualization of some of the data produced for a pendulum of mass and radius of m = × kg and r = . m, respectively, at one snapshot in time. section . explores the underlying fluid dynamics in further detail, including the time evolution over a pendulum’s first swing, see figure . fluids , , of figure . snapshots of a single moment in time for a pendulum with mass, m = × kg, and radius, r = . m, providing some of the data stored during the time-step in which the simulation time reached t = . s, i.e., positions of lagrangian points (pendulum), the velocity vector field, magnitude of velocity, and vorticity. note that data from giving the force spread from the lagrangian grid (pendulum) onto the eulerian (fluid) grid is not shown. lagrangian coherent structures (lcs) via finite time lyapunov exponents (ftle) are also illustrated, although they were computed during the post-processing stage, after the data was collected. . results using an open source implementation of the immersed boundary method, ib d, we modeled the motion of a pendulum with a circular bob immersed within a fluid undergoing gravity’s influence. for this education focused paper, we explored angular displacement and speed of the pendulum bob as well as forces acting upon the pendulum bob to impede its motion. upon doing so we quantified the decay in oscillation amplitude and speed damping. this was done for a variety of pendulum bob masses as well as radii (size). we also explored the effect that the motion of the pendulum bob has onto the fluid it was immersed. lastly, we compared the reduced ode model of a damped physical pendulum and our fsi model. we organized our results into the following five subsections: . angular displacement of the pendulum bob . speed of the pendulum bob . forces acting on the pendulum bob . effect the pendulum bob has onto the fluid . comparison between reduced ode model and fsi model . . angular displacement of the pendulum bob as suggested from section , since the pendulum is immersed within a fluid environment, its oscillation amplitude will decay over time. figure provides snapshots of multiple pendulums’ angular displacement over time for pendulum bobs of differing radius and m = × kg. note that all simulations were run independently of each other and lagrangian position data is being overlaid during post-processing. fluids , , of figure . snapshots of multiple pendulums’ (of differing radius) angular displacement over time in the case of m = × kg. moreover, both the size of the bob and the mass of the bob will affect its dynamics. figure illustrates that pendulums with the same size and shape bob may experience significantly different oscillation patterns due to different mass. in particular, depending on the mass, the pendulum could fall into any of the damping cases (under-, over-, or critically-damped). see figure a for the counterpart case where a specific mass is tested for a variety of radii. consistent dynamics are observed. figure . depicting the angular displacement (radians) vs. time (s) for pendulums with the same radius but different masses. (a–c) give data for a specific radius, either r = . m, . m, or . m, respectively, for orders of magnitudes in mass in each. next we calculated the maximum amplitude during each oscillation cycle for a variety of masses. the amplitude decays exponentially, see figure . figure presents the displacement amplitude against peak number (number of half swings) for a variety of masses for r = . m. the data shows a linear relationship between the logarithm of the amplitude and the peak number, suggesting exponential decay, although lines seem a better fit starting at the first peak, rather than the initial displacement. note that figure shows a steady increase in time between successive peaks for three fluids , , of different masses (m = × , × , and × kg) for a variety of radii. as mass increases, the time between peaks decreases. moreover, generally as more swings occur the time become peaks becomes more consistent. we also note that the time between the start of each simulation and their first peak generally does not fit the data. sections . , . and . will also explore this observation in more detail. figure . (a) plot illustrating the decay of the height (m) that the pendulum bob reaches as the pendulum continues to swing for the case of r = . m for a spectrum of masses. the peak amplitude decays exponentially as illustrated by the linear relationship between the logarithm of the amplitude against peak number, as shown in (b). figure . plots illustrating the time of the peak in angular displacement against the pendulum bob’s radius for its st through th peak (a–c) and the time difference between the peaks (d–f) against the pendulum bob’s radius for three different masses: (a,d) m = × kg, (b,e) m = × kg, and (c,f) m = × kg. from this data, we computed the approximate damped period of oscillation, see figure a,b. figure b provides a colormap with contour lines of the period data from figure a. as mass increases, the approximate period decreases, as suggested previously. moreover, as radius increases, the period also increases. note that when mass is high enough (e.g., the case of m = × kg), the period fluids , , of does not significantly change between different radii; however, there is still exponential decay in the oscillatory amplitude (see figure a ). furthermore, for very small radii there appears to be a non-monotonic trend in period as a function of mass. the period was computed by averaging the time between every other peak over the first full oscillations. next we explore how the speed of the pendulum bob is affected by variations in its mass and radius in a fluid environment. figure . (a) the period given as a function of a pendulum bob’s radius for a variety of masses. (b) a contour map showing the period as a function of both the pendulum bob’s radius and mass. the highest periods occur for small masses and large pendulum bobs. . . speed of the pendulum bob recall that in section . we observed that peaks in angular displacement decayed exponentially over time. this suggests that the pendulum bob’s speed is inherently slowing down as well. figure details the pendulum bob’s speed vs. the number of swings (half a complete oscillatory cycle). the data shown is for the case of r = . m for a variety of masses. during each swing the pendulum accelerates to a maximal speed before decelerating. the maximum occurs at roughly halfway through each swing, when the pendulum passes the point of displacement from the vertical. note that physically the pendulum must hit a speed of zero when it swings from one direction to the other; our data does not reflect this due to the time resolution of the sampled time-points. furthermore, from figure b, it does not appear that the speed peaks decay exponentially over time from the beginning of the simulation. after a few swings, the peaks in speed appear to satisfy a linear relationship between the logarithm of speed versus time; however, the peak speed significantly decreases from the first to second swing, see figure . figure illustrates that for most cases from the second swing on, the peak speeds approximately demonstrate exponential decay; however, there is significantly more decay between the first and second swing than successive peaks thereafter. figure a presents the counterpart data of how the speed of pendulum bobs of the same mass decays over time for a variety of radii. similarly trends are observed in the data. fluids , , of figure . (a) plot depicting the linear speed of the pendulum bob against non-dimensional time given as the # of swings (half a full displacement cycle) for the case of r = . m and a variety of masses. speed peaks near the center of each swing. this corresponds to when the pendulum has approximately zero angular displacement from the vertical. the peak speed appears to begin decaying exponentially, starting on the second or third swing in most cases. this can be seen from linear relationships between peak speed and swings in (b). figure . plot illustrating that exponential decay appears in peak speed starting with the second swing. there is significantly more decay in peak speed between the first and second swings, than successive swings thereafter. next we wished to quantify the amount of damping due to the pendulums immersion in a fluid of kinematic viscosity ν = µ/ρ = − m /s. to do this we computed the theoretical speed of a pendulum bob void of a fluid environment by energy conservation. we set the original potential energy when the pendulum bob was at time zero and computed the kinematic energy when the pendulum was passing displacement, i.e., mv n f = mgh ⇒ vn f = √ gh , where vn f is the velocity of the pendulum bob outside of a fluid environment and h is the initial height of the pendulum bob before it begins swinging. for our initial setup, h = l( − cos(π/ − π/ )), since the pendulum is released from an initial angle of π/ radians from the horizontal. we then defined the speed ratio to be: sr = v/vn f and the speed damping ratio to be: sdr = − sr = − v/vn f . if v = vn f , sdr ≈ suggesting only small damping effects. figure gives the fluids , , of speed damping ratio as a percentage. for this particular fluid environment, even cases of high mass and small radius result in sdr’s of ∼ %, i.e., the fluid immersed pendulum bob is moving ∼ % slower than its fluid void counterpart. as the radius increases, the sdr increases. note that smaller masses have less significant increases in sr. as mass increases, sdr decreases for a given radius. figure . the percentage decrease in speed when comparing pendulum bob speed once it reaches degree angular displacement on the first swing compared between simulated cases in fluid and theoretical value outside of a viscous fluid environment. lastly we explored the phase space between pendulum bob speed and its angular displacement. figure a presents the data for the case of r = . m for a spectrum of masses of over orders of magnitude. as suggested by all data previously, the trajectories eventually converge to zero displacement and speed. interesting, all the trajectories collapse onto an approximate parabolically-capped cone. the last cycle is given for all cases in figure b. similar topologies are seen in cases of other radii (see figure a ) over a variety of masses. furthermore, similar topologies emerge when fixing the mass and exploring trajectories for a variety of radii (see figure a ). figure . (a) phase space of linear speed of the pendulum bob vs. angular displacement (radians) for a variety of masses in the case of r = . m. (b) a closer look at the last simulated cycle’s phase space in each case. fluids , , of . . forces on the pendulum bob we have observed that a fluid-immersed pendulum experiences exponential decay in angular displacement and speed. as discussed in section , this is due to fluid drag on the pendulum bob. in this section we will explore this drag force. we wish to emphasize that our numerical experiments did not prescribe any specific form of the drag forces a priori, or any forces for that matter, beyond gravity acting on the pendulum bob. first we selected three masses, m = × , × , and × kg, and investigated the drag force acting on the pendulum versus time for a variety of radii. this data is shown in figure . the drag force was calculated by computing the forces perpendicular to the direction of the pendulum arm as the bob swung. a normal unit vector was computed at each sampled time-point and the drag force was computed using a vector projection in the direction opposite to the swinging motion of the pendulum bob. figure a–c suggest that the drag force exponentially decays as time progressed. this was further confirmed by the linear relationship between the logarithm of drag force vs time in figure d–f. as the radius increases, the surface (circumference) of the circle increases, and thus the amount of drag on the pendulum bob’s body increased for a particular mass as well. hence the drag on the bob is dependent on its geometry (shape and size), as discussed in section . furthermore, as mass increases, so does the overall drag on the bob. this can also be seen in the counterpart case, where radii are selected (r = . , . , and . m) and mass was varied, see figure a . figure . drag forces (n) over time in seconds for multiple radii for cases with (a,d) m = × kg, (b,e) m = × kg, and (c,f) m = × kg. the semi-log data is provided in (d–f) to highlight a linear relationship between the logarithm of the drag force and time. this linear relationship suggests an exponential decay in drag force over time. next, we explored the phase space of drag force on the pendulum bob versus angular displacement of the bob. this data is given in figure . similar to the phase plots of speed versus displacement, the force-displacement trajectories all collapse onto a unique exponentially decaying envelope. smaller radii (figure a, r = . m) correspond to larger angular displacements and larger spectrum of initial drag forces corresponding to a variety of masses over orders of magnitude. in the case of a larger radii (figure c, r = . m), there are smaller angular displacements, comparatively, and the range of initial drag forces is smaller for the same variety of masses. fluids , , of figure . phase space of drag force (n) versus angular displacement (radians) for a variety of masses in cases of (a) r = . m, (b) r = . m, and (c) r = . m. the data for each case of a specific radius appears to overlap as well as suggesting that as the peaks in angular displacement decay exponentially (see figure ), the drag forces also decay exponentially as well. finally, we wish to compare force information across all cases of radii and masses considered. the metric we chose to compare for each is the drag coefficient; recall the cd term from equation ( ). to justify our use of equation ( ), we verified that the pendulum simulations fell into the appropriate reynolds number range, i.e., re > . recall the reynolds number, re, is defined to be re = ρlv µ , ( ) where ρ and µ are the fluid’s density and dynamic viscosity, and l and v are a characteristic length and velocity scale, respectively. we chose l to be the length the pendulum’s arm, but rather than select v to be a constant, we used the time-dependent speed of the pendulum bob for each case. note that this speed is inherently a function of the radius of the pendulum bob itself, see figure a in appendix c. figure a illustrates that for m = × kg that the peak in reynolds number is greater than one. moreover, where re drops down, i.e., at the beginning and end of each swing, is where speed is near zero. thus we assume the drag force law derived by lord rayleigh will suffice for our purposes here (fd ∼ v , see equation ( )). note that as the pendulums continue to swing, re(t) will decrease in every case. eventually there will be a shift into the regime where lord rayleigh’s drag force law begins to fail and one must consider stokes drag law (fd ∼ v, see equation ( )) when re < . furthermore, we computed the time-averaged reynolds number over the first swing of the pendulum for all masses and radii considered, see figure b. generally, as the mass of the bob increases, the average re increases. on the other hand, as the radius increases, average re decreases. figure . (a) re vs. time for m = × kg and (b) a colormap depicting the temporally-averaged reynolds number during the first swing for different masses and radii. note that over time as the pendulum slows down, the average reynolds number will decrease. fluids , , of upon calculating equation ( ), we also need to describe a, the cross-sectional area of the circular pendulum, and fd , the drag force on the pendulum. we define a to be the circumference of the circle, i.e., a = πr, for each given radius, r. having computed the speed of the pendulum bob and drag force on the body previously, we could solve for the time-dependent drag coefficient cd at each sample time-point using equation ( ). figure a,b gives cd(t) over the first swing (half an oscillation cycle) and swings ( full oscillation cycles), respectively, for the case of m = × and a variety of radii. note that the cd peaks correspond to when the pendulum bob changes direction and thus reach speeds near zero. moreover, the time-dependent drag coefficients will increase over time due to the pendulum continually slowing down. figure . the drag coefficient, cd , during the first pendulum’s first swing (a) and first -swings (b) for a variety of radius in the case of m = e kg. note that the drag coefficient maximizes when the pendulum reaches near zero speed at the end of a swing. (c) the temporally-averaged drag coefficients across the first swing for all mass and radius cases considered. (d) a contour map of the temporally-averaged drag coefficients over the first swing from (c) as a function of both the pendulum bob’s mass and radius. generally higher drag coefficients are seen for larger mass and size pendulum bobs. in order to compare all simulations of differing mass and radii, we averaged the time-dependent drag coefficient, cd(t), over the first swing, as shown in figure c,d. figure d provides a colormap with contour lines of the time-averaged drag coefficient using the data from figure c. larger radii pendulums tend to have larger drag coefficients and higher mass pendulum bobs also have larger drag coefficients. notice that a pendulum bob with same shape (circle) and size (radius) could elicit different drag coefficients based on variations in mass. from section . we have already observed fluids , , of that variations in mass give rise to variations in speed, which is also required to compute cd in the first place. the system is highly coupled in its many dynamical features! finally, we highlight the relationship between drag coefficient, cd , and reynolds number, re, in figure . for a given mass (mass is denoted by a particular shape in the figure), as average re increases, cd decreases. as the system is highly coupled, for a given mass, the average re only increases as the pendulum bob’s radius decreases (radius is denoted by the colormap). on the other hand, for a given radius, as the mass increases, the average cd and re also generally increase. the overall trend of decreasing cd with increasing re is common in many fluid dynamics phenomena, not only physical experiments, such as flow past rigid objects [ – ], but also in biology, such as tiny insect flight [ , ], or even sports such as baseball [ ], american football [ ], or football (soccer) [ ]. figure . the average drag coefficient, cd , vs. average reynolds number for a variety of masses and radii. the averages were computing over the first swing of the pendulum bob. . . effect the pendulum bob has onto the fluid in addition to the data analysis performed in sections . – . , which focused primarily on the lagrangian structure itself—the pendulum, cfd (fsi) simulations grant us the opportunity to analyze how the underlying fluid reacts to a pendulum swinging through it. also, we are able to visualize the fluid dynamics and observe the evolution of the fluid’s velocity field, u(x, t), magnitude of velocity, |u(x, t)|, and vorticity (∇× u(x, t)), see figure , for qualitative analysis. figure shows the resulting fluid dynamics due to the swinging motion of the pendulum bob of mass, m = × kg, and radius, r = . m, during its first swing. as the pendulum swings, there is a pocket of fast moving fluid directly behind the bob until it passes zero angular displacement, as shown by the velocity field and magnitude of velocity plots. note that streamlines are presented on the velocity field’s plots and contours are given on the magnitude of velocity plot, as well. streamlines illustrate the path of massless tracer particles in the flow at an instantaneous point in time, while the contours give a line in which the quantity (here, magnitude of velocity) has constant value. note that the direction of the pocket of fast moving fluid is towards the pendulum bob; hence objects directly behind the moving bob receive an fluid dynamic benefit. this phenomenon is commonly called drafting and has been studied in the context of many sports, such as ice skating [ ], running [ , ], swimming [ ], or cycling [ ], as well as biological locomotion [ – ]. within the region of fast moving fluid there are two interacting, oppositely spinning vortices behind the bob, as illustrated by the vorticity plots. when the vortices are shed off the bob entirely, i.e., once the bob swings past zero displacement, the vortex pair continues to move vertically downwards, rather than upwards and to the right with the bob. these visualizations were produced using the raw .vtk-data produced during the fsi simulations using the open-source software visit [ ]. we wish to fluids , , of emphasize that one cannot gain knowledge of fluid dynamics from the reduced-order ode model, equation ( ) alone. moreover, because of the fsi simulations we are able to analyze the fluid data further and determine regions that have varying levels of fluid mixing. during data post-processing we could compute the finite-time lyapunov exponents (ftle), which can be used characterize the rate of separation in the trajectories of two infinitesimally close fluid blobs. maxima in the ftle (called ridges) have been used to determine lagrangian coherent structures (lcss), which are used to determine distinct flow structures in the fluid [ – ]. lcss are a tool to divide the fluid’s complex dynamics into distinct regions to better understand transport properties of flow [ – ]. in this paper, we computed forward-time ftle field, whose maximal ridges give lcss corresponding to regions of repelling fluid trajectories and low values give rise to regions of attraction [ ]. this data is presented in figure as well. our desire here is not to emphasize fluid mixing metrics, but merely point out that through cfd one is able to investigate deeper dynamics of a system, even one as well studied as a damped pendulum. figure . colormaps (and its contours) illustrating the time evolution of the fluid’s vorticity, magnitude of velocity, and finite-time lyapunov exponent (ftle), as well as the velocity field (and its streamlines) resulting from the pendulum bob’s first swing in the case of m = × kg and r = . m. fluids , , of furthermore, we wish to point out that the resulting fluid dynamics are diverse. not every pendulum bob sheds vortices in the same way as the case of (m, r) = ( × kg, . m) (as illustrated in figure ). figure illustrates differences in vortex formation and shedding for the case of m = × kg for a variety of radii during the first swing. in particular the overall size and magnitude of vortices formed is less in the smaller radius cases; however, once shed, the vortex dynamics are different. this would give rise to different dynamics in drafting behind the bob. in the larger radius cases (r > . m), the vortices move vertically downwards upon being shed, while they are significantly different in the smaller cases: in the r = . m case, the vortex-pair travels along with the pendulum bob, and for r = . m two sets of vortex-pairs move on either side of the pendulum bob. thus, modifying the size of the pendulum results in different dynamics of the underlying fluid, even though all pendulums swing along the same circular arc; however, they do so at different speeds. figure . comparing vortex dynamics among pendulum bob of different radii for a mass of m = × kg. lastly, taking a further look at the r = . m case (for m = × kg) reveals that as the pendulum swings, it swings back through its vortex wake, see figure . the act of swinging through its vortex wake has been suggested as a possible mechanism for increased fluid drag on the pendulum bob [ ]. however, a vortex could also enhance the speed of the bob if an appropriately spinning vortex interacts with the bob at the right moment in time, see t = . s in figure . the vortex in red is spinning counter-clockwise and may give the bob a boost in speed, as it is moving in that same direction. there are complex interwoven dynamics within the system. figure provides an additional sequence of snapshots depicting these complex interactions. it shows a pendulum bob fluids , , of (m = × kg, r = . m) swinging through its own vortex wake during the return swing of the first oscillatory cycle. such complex interaction mechanisms have not been fully explored and warrant further attention from the scientific community. figure . the vortex dynamics of the case (m, r) = ( × kg, . m) within the first s of oscillation. figure . the vortex dynamics of the case (m, r) = ( × kg, . m) on the return swing during its first oscillatory cycle. . . numerical comparison & validation lastly, in this section we will compare and validate the canonical damped physical pendulum equation against our fluid-structure interaction (fsi) model. recall the damped physical pendulum (equation ( )) is given by d θ dt + b i dθ dt + mgl i sin θ = . ( ) fluids , , of our fsi model did not assume any knowledge of the existence of this reduced ordinary differential equations (ode) model. instead it placed a spherical (circular) pendulum bob into a fluid environment, tethered it to a fixed location, and under the influence of gravity alone, it swung. this was to mimic a physical experiment, but performed in silica, rather than in a laboratory setting. to compare equation ( ) and our fsi model, we first matched the parameter values. for each radius and mass considered in our fsi model, we were able to compute the exponential decay of the peaks in angular displacement amplitude using a linear least squares framework to fit a line through the logarithm of the peak values in angular displacement over time (linear regression), see figure a as an illustrative example. the slope of each line was γ = − b i for that particular mass and radius. hence for the parameter b/i in equation ( ), we multiplied each slope γ by − , i.e., b/ i = − γ. ( ) note that the term mgli is the approximate natural (undamped) angular frequency squared of the pendulum bob, i.e., ω n = mgl i . ( ) note that this is not the true natural, undamped angular frequency, as we did not invoke the small angle approximation, i.e., sin θ ≈ θ for small θ [ ]. moreover, due to the presence of the fluid, the pendulum bob was not in an undamped setting, so we could not directly calculate ωn from our numerical experiments. however, we used the pendulum’s period, as previously computed in section . , and γ to compute ω n . for clarity with the undamped case, we define td and ωd to the damped period and angular frequency of our pendulum bob from the fsi experiments. recall the relationship between ωd and td , ωd = π td , ( ) and the relationship between ωn , ωd , and γ, ω d = ω n − γ . ( ) hence using equations ( )–( ), we can compute the natural (undamped) angular frequency, ω n = mgl i = π t d + γ . ( ) using equations ( ) and ( ) we found the appropriate parameter values for the reduced ode model, as computed from the fsi simulations. figure b–f provides comparison of the fsi and ode models’ angular displacement over time for a variety of pendulum bob radii and masses. for comparative purposes, the ode model was initialized at the th peak of the fsi model and its solution was computed by propagating both forwards and backwards in time. moreover we also plotted the exponential decay, using the th peak amplitude as the coefficient, and plotted it in a similar manner both forwards and backwards in time from the th peak. fluids , , of figure . (a) slopes of the least squares (linear regression) fits through the peaks of angular displacement over time to compute the exponential decay, γ = − b i , for a variety of radii in the m = × kg case. (b–f) comparison of the fsi and ode models’ angular displacement over time for a variety of masses and radii. fluids , , of we note that the ode model only agrees with our fsi model after a few oscillations. if we propagated the ode model forward in time from the original position of the fsi pendulum, angular displacements were not consistent, see figure . furthermore, if we used the first peak amplitude (initial angular displacement) as the coefficient on the exponential decay, the fsi model appeared to not agree with its own decay rate. however, the decay rates are consistent, as seen in figure , but the fsi model does not start obeying such decay until after a few oscillations. thus, the decay rates, γ = − b i , were calculated starting with the third peak rather than the initial displacement. we chose the third peak rather than the second as the linear relationship was more prevalent from that point on. this is the same phenomenon from figure in section . , where the exponential decay in peak speeds did not start until what appeared to be the second swing. figure . depicting the dynamics if the ode model started from the original angular displacement of the fsi pendulum rather than the the th peak for the case (m, r) = ( × kg, . m) and (m, r) = ( × kg, . m) for (a,b), respectively. a visualization of the exponential decay is also provided with the coefficient either being a , the original angular angular displacement, or a , the displacement of the th peak. overall the reduced ode model agrees with the fsi model after a few oscillations for different size pendulum bob radii as well as over a spectrum of masses; however, the dynamics during the first swing are substantially different (see figure ). this is possibly due to a different fluid drag law on the pendulum, before it settles into the regime where the drag can be modeled as linearly proportional to its velocity. lastly, we computed the damping parameter, b, by itself as a function of the mass and radius of the pendulum bob. to compute this, we first found the effective moment of inertia of each case using equation ( ), e.g., i = mgl π t d + γ , ( ) and then calculated b = − γi. ( ) note that we chose to calculate the effective moment of inertia, i, for each simulation here. our fsi pendulum bob geometry was not a solid structure, but rather, had a singular mass source at its center, a shell composed of neutrally-buoyant points tethered together, and from the ib formulation, its shell enclosed fluid within. this fluid had the same properties as the backward fluid environment in which the pendulum is immersed. moreover, as the principle of added mass states that inertia is added to a fluid system when an object is accelerating (or decelerating) through it [ ]. thus, the appropriate moment of inertia, i, to use in the ode model to match the fsi model is non-trivial. fluids , , of the damping parameter, b, increased as mass increased for a particular radius, see figure . moreover, as the radius increased for a given mass, b increased as well. while the system appears to be more sensitive to changes in mass, recall that the mass was varied over two orders of magnitudes in value, while the radius varied roughly over one. figure . values of the damping parameter, b, as a function of the mass and radius of the pendulum bob. . discussion and conclusions two-dimensional immersed boundary simulations were used to model the swinging motion of a circular pendulum bob under the influence of gravity that was contained within a viscous, incompressible fluid environment. in addition, to the authors knowledge, this is the first fluid-structure interaction (fsi) simulation that explores the motion of an ordinary pendulum system which also offers an open-source complement. the angular displacement data collected from the motion of the pendulum bob was directly compared against the reduced-order damping ode model that is familiar to most stem students. in general, the oscillatory dynamics agree between the ode model and the fsi model (see section . ). however, there were discrepancies in the decay rates between the first few swing’s maximal angular displacements and speeds with those following thereafter. the mechanisms underlying these observations are not fully understood. there appear to be interesting dynamics to probe further involving the pendulum bob’s mass and radius, the vortex wake it creates, the interactions of those vortices with each other and the bob itself, and the resulting drag on the bob during large amplitude oscillations. moreover, the ode model’s linearly-proportional-velocity damping term, i.e., stokes drag law, was appropriate once the pendulum has swung a few times after a large initial angular displacement. during the first initial swing there was an enhancement of drag on the pendulum bob, potentially obeying rayleigh’s drag law and/or from the principle of added mass [ ] and/or other complex drag mechanisms involving vortex shedding [ ]. furthermore, we were able to determine the approximate damping parameter, b, that fit the ode model from our fsi model. the damping parameter, b, was found to be dependent on both mass and radius of the pendulum (see section . ). also, through the fsi simulations, we were able to quantify how the drag coefficient, cd , increased with both increasing mass and radius of the pendulum bob (see section . ). on that note, we also illustrated how the pendulum’s period of oscillation was a function of both the mass and radius of the pendulum bob (see section . ). fluids , , of beyond the dynamics of the pendulum structure itself, using a fsi model allowed us to peek into the resulting dynamics of the underlying fluid (see section . ), which we would not have otherwise been able to do using the reduced-ode model alone. while the purpose of this study was to explore the dynamics of a fsi pendulum model, which inherently did not assume any particular drag laws a priori, and compare the results to the ode model, this framework can be used to further probe into new scientific frontiers that could unravel the enhanced contributions to fluid drag, whether from traveling through your own vortex wake, as suggested by mathai et al., [ ], vortex shedding as suggested by bolster et al., [ ], or added mass, as suggested by bandi et al., [ ]. there are still complex relationships to decrypt between oscillatory amplitude, geometry and mass of the pendulum bob, and fluid scale. the aforementioned studies performed physical experiments with pendulums and used sophisticated visualization techniques, either the baker electrolytic technique [ ] or particle image velocimetry (piv) [ , ] to visualize the underlying fluid dynamics. furthermore, using this fsi framework it is possible to couple multiple pendulum together and study the resulting complex dynamics and/or investigate the motion of a variety of geometric objects being swung as pendulum bobs. we have seen that the size of the pendulum bob affects the underlying fluid dynamics, as observed through different vortex dynamics in section . ; however, one has yet to explore how shape affects the fluid dynamics or motion of the bob itself. while a student’s first brief foray into fluids may have been through the concept of damped simple harmonic motion involving a pendulum, we hope that this manuscript provides the following context for students in an introductory fluid mechanics course: • a connection to where students may have seen fluid drag laws previously, i.e., the stokes drag law and pendulum motion. furthermore, it illustrates for students that famous laws of physics were discovered with systems that seem as “basic” as that of a pendulum. • the differences that may arise between modeling a system using a reduced-order ode model and attempting to computationally model all aspects of the system to a higher degree. we hope this shows students that reduced models are valuable in that they are usually easier to solve while (hopefully) capturing a bulk of a system’s dynamics. however, there are clear disadvantages as illustrated by the discrepancies that arise between the reduced order model and computational model—many dynamics are not captured in the reduced-model, e.g., the vortex wake or drafting, that maybe particularly interesting or important to understanding the system as a whole. • similarly, the full dynamical richness of a system may only be explored by investigating its explicit fluid mechanics, even in a system as seemingly “simple” as a single pendulum immersed in a fluid. moreover, to even study systems involving fluids and objects immersed therein, it requires either sophisticated experimental techniques or computational expertise. this work shows that a computer can be an immensely powerful tool for performing science. more than that, programming knowledge is highly sought after in this day and age [ , ]. • the observation that even systems that are routinely studied in some introductory courses, like a pendulum, may still have open, exciting research questions that scientists and engineers actively pursue. to conclude, the pendulum may be an old, historic device that has been studied for millennia; however, under the hood, there are a lot of hidden, complex dynamics left to discover. supplementary materials: the following are available online at http://www.mdpi.com/ - / / / /s . author contributions: conceptualization, m.m. and n.a.b.; methodology and software, n.a.b.; validation, n.a.b.; formal analysis, investigation, and data curation, m.m. and n.a.b.; writing—original draft preparation, n.a.b.; writing—review & editing, m.m. and n.a.b.; visualization, m.m. and n.a.b.; funding acquisition, n.a.b. all authors have read and agreed to the published version of the manuscript. funding: computational resources were provided by the nsf oac # and the nsf oac # . support for n.a.b. was provided by the tcnj support of scholarly activity (sosa) grant, the tcnj department of mathematics and statistics, and the tcnj school of science. http://www.mdpi.com/ - / / / /s fluids , , of acknowledgments: the authors would like to thank christina battista, robert booth, karen clark, jana gevertz, christina hamlet, alexander hoover, laura miller, matthew mizuhara, arvind santhanakrishnan, emily slesinger, edward voskanian, and lindsay waldrop for comments and discussion. conflicts of interest: the authors declare no conflict of interest. abbreviations the following abbreviations are used in this manuscript: cfd computational fluid dynamics fsi fluid-structure interaction re reynolds number ib immersed boundary method ode ordinary differential equation appendix a. instructor resources teaching resources: associated supplemental files contain slides, movies, and open-source codes pertaining to the paper. it encompasses the following: . pendulum_classroom_supplement.pptx/.pdf: presentations which may be used in class; slides that tell the story of the paper. note that the .p ptx file has embedded movies in .m p format. . movies: directory containing movies (.m p format) pertaining to each simulation shown in the manuscript. . note that an open-source fluid-structure interaction model of a point-mass pendulum can be found at: https://github.com/nickabattista/ib d in the sub-directory: ib d → matib d → examples → examples_education→ pendulum. . visualization software used: visit (https://visit.llnl.gov/) (v. . . ) appendix b. immersed boundary method the immersed boundary method [ ] was used to model the motion of a pendulum under gravitational acceleration, see section . although, ib is capable of solving fully coupled fluid-structure interaction systems involving flexible or squishy structures, here we use it to model the stiff boundaries of a pendulum bob immersed within an incompressible, viscous fluid. the fluid motion is governed by the navier-stokes equations, given as ρ ( ∂u(x, t) ∂t + u(x, t) ·∇u(x, t) ) = −∇p(x, t) + µ∆u(x, t) + f(x, t) (a ) ∇· u(x, t) = , (a ) where u(x, t) = (u(x, t), v(x, t)) is the fluid velocity, p(x, t) is the pressure, f(x, t) is the force per unit volume (area in d) applied to the fluid by the immersed boundary, i.e., the pendulum. the independent variables are the position, x = (x, y), and time, t. equations (a ) and (a ) are conservation laws for the fluid, i.e., the conservation of momentum and mass, respectively. note that equation (a ) is known as the incompressibility condition. the interaction equations between the fluid and the immersed structure are given by f(x, t) = ∫ f(r, t)δ(x − x(r, t))dr (a ) u(x(r, t), t) = ∂x(r, t) ∂t = ∫ u(x, t)δ(x − x(r, t))dx, (a ) https://github.com/nickabattista/ib d https://visit.llnl.gov/ fluids , , of where x(r, t) gives the cartesian coordinates at time t of the material point labeled by lagrangian parameter r, f(r, t) is the force per unit area imposed onto the fluid by elastic deformations in the boundary, as a function of the lagrangian position, r, and time, t. equation (a ) applies a force from the immersed boundary to the fluid grid through a delta-kernel integral transformation. equation (a ) sets the velocity of the boundary equal to the local fluid velocity. as suggested in section . , the deformation force equation, f(r,t), is specific to the system being explored. for this pendulum model, it takes the following form f(r, t) = fs pr + ftarget + fmass, (a ) that is the summation of forces arising from spring, target point, and massive point deformations pertaining over each lagrangian point being modeled with one or more of this model features. ib algorithm in our pendulum model, we imposed periodic boundary conditions on a square domain. to solve equations (a )–(a ) we need to update the velocity, pressure, and both the position of the boundary and forces acting on it from the previous time-step data, time n. ib traditionally does this in the following steps [ , ]: step : calculate the force density, fn on the immersed boundary, from its current boundary configuration at time n, xn. step : use equation (a ) to spread the force from the lagrangian boundary to the eulerian (fluid) mesh to compute fn step : solve the navier-stokes equations, a and a , on the eulerian grid, thus updating un+ and pn+ from un, pn, and fn. step : update the lagrangian point positions, xn+ , using the local fluid velocities, un+ , computed from un+ and (a ). we quickly note that to approximate the integrals in equations (a ) and (a ), discretized (and regularized) delta functions were used. we chose to use the delta functions described in [ ], i.e., δh(x), δh(x) = h φ ( x h ) φ (y h ) φ ( z h ) , (a ) where φ(r) is defined as φ(r) =   ( − |r|+ √ + |r|− r ), ≤ |r| < ( − |r|+ √ − + |r|− r ), ≤ |r| < ≤ |r|. (a ) appendix c. additional pendulum data in this appendix we provide complementary data to the data presented in section , e.g., if we provided a figure that contained a variety of masses for a particular radius (as in figure ), here we will provide the opposite—a variety of radii for particular cases of mass (as in figure a below). these figures are provided for additional clarity in regards to the comparisons being discussed and analyzed. first we provide the angular displacement (in radians) over time (in seconds) for cases of pendulums with the same mass, but different radii in figure a . this data is to illustrate clearly that pendulum bobs with the same mass can experience different oscillatory patterns for different radii. moreover, it appears that by increasing mass orders of magnitude, from × kg to × kg to × kg could result in the pendulum bob undergoing different regimes of oscillation—either underdamped to overdamped. fluids , , of figure a . depicting the angular displacement (radians) vs. time (s) for pendulums with the same mass but different radii. (a–c) give data for a specific mass, either m = × kg, × kg, or × kg, respectively, and a variety of radii in each. next we provide a plot of the height the pendulum reaches (in meters) as a function of the peak number in angular displacement for m = × kg and a variety of radii in figure a . this illustrates that as the radius increases, the height decreases. not only does the height decreases as the radius increases, the linear speed of the pendulum also decreases as well, as given in figure a . our simulations suggest that smaller pendulum bobs generally move faster than larger ones for a given mass. in both of these figures, among all cases, both the speed and height decay exponentially as illustrated by the semi-logarithmic plots in figures a b and a b. these data are provided to suggest that as the size of the pendulum increases, there must be more drag force acting on the bob to decelerate their speed and thus not allow them to reach as great of heights (angular displacements) as other smaller bobs. figure a . (a) plot illustrating the decay of the height (m) that the pendulum bob reaches as the pendulum continues to swing for the case of m = × kg for a variety of radii. the peak amplitude decays exponentially as illustrated by the linear relationship between the logarithm of the amplitude against peak number, as shown in (b). fluids , , of figure a . (a) plot depicting the linear speed of the pendulum bob against non-dimensional time given as the # of swings (half a full displacement cycle) for the case of m = × kg for a variety of radii. speed peaks in the middle of a swing corresponding to when the pendulum has zero angular displacement from the vertical and the peak speed appears to decay exponentially, given by the linear relationship in (b). furthermore we also provide more detailed phase space explorations of linear speed (m/s) versus angular displacement (radians) in figures a and a . figure a provides the phase space of linear speed versus angular displacement for the case of m = × kg and a variety of radii, while figure a selects four radii (r = . m, r = . m, r = . m, and r = . m) and varies mass. similar topological structures are observed, where the data collapses onto a parabolically-capped cone. this is intuitive as both the peaks in angular displacement and speed decrease over time; however, what is particularly interesting is that the cone angle looks to be approximately conserved among all cases. figure a . (a) phase space of linear speed of the pendulum bob vs. angular displacement (radians) for a variety of radii in the case of m = × kg. (b) a closer look at the last simulated cycle’s phase space for each case. fluids , , of figure a . phase space of linear speed of the pendulum bob vs. angular displacement (radians) for a variety of masses for cases: (a) r = . m, (b) r = . m, (c) r = . m, and (d) r = . m. finally we provide data depicting the drag force (n) over time for different radii (r = . m, r = . m, and r = . m) over a variety of masses. compared to figure , we notice that for the same radius but different masses, the drag forces begin to overlap with time. specifically, the drag forces corresponding to larger masses decay more rapidly. this could also be surmised from figure c,d, which show an increased average drag coefficient during the higher mass cases for a specific radius. fluids , , of figure a . drag forces (n) over time in seconds for a variety of masses for cases with (a,d) r = . m, (b,e) r = . m, and (c,f) r = . m. the semi-log data is provided in (d–f) to highlight a linear relationship between the 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https://shaddenlab.berkeley.edu/uploads/lcs-tutorial/lcsdef.html https://doi.org/ . / . https://doi.org/ . / . http://www .cscamm.umd.edu/programs/trb /presentations/piv.pdf http://www.dantecdynamics.com/measurement-principles-of-piv http://www.dantecdynamics.com/measurement-principles-of-piv https://www.compadre.org/jtupp/docs/j-tupp_report.pdf http://creativecommons.org/ http://creativecommons.org/licenses/by/ . /. introduction methods model geometry model construction results angular displacement of the pendulum bob speed of the pendulum bob forces on the pendulum bob effect the pendulum bob has onto the fluid numerical comparison & validation discussion and conclusions instructor resources immersed boundary method additional pendulum data references small is beautiful small is beautiful a miniature stent model mark j. post, johannes waltenberger r ecent successes by drug eluting stents in the battle against restenosis have boosted the volume of stent related research. the goal of this research is to further reduce restenosis rates by improving stent and polymer design and by testing and modifying drugs from various classes. the novel mouse model described by ali et al, offers new opportunities to study fundamental and perhaps applied aspects of vascular biology related to stent implantation. in the absence of in vitro models of vascular healing that eventually may replace animal experiments, small animal models are especially welcome. the first mouse model of vascular healing was developed by lindner and coworkers more than years ago. they injured the carotid artery with a guide wire and observed the same sequence of apoptosis, invasion of leukocytes, smooth muscle cell migration, and proliferation and reendothelialization as found in rabbits, pigs, and humans. animal models of diseases and related therapies serve two purposes: to increase the understanding of pathobiology and to evaluate new therapies down to the histopathologic level. models are simplifications of reality, and animal models are no exception. the predictive value of a model depends on a largely empirical framework that links animal behavior with clinical experience. fortunately, animal models of vascular healing in various species and arterial beds have already provided a solid reference for this novel stent model. most of these models, however, especially in rats, lack preexistent pathology such as atherosclerosis, which may explain some of the false-positive results with pharma- cological inhibition of intimal hyperplasia. the various mod- els of atherosclerosis that are currently available in mice may provide a more realistic response to vascular injury. see page the presented mouse stent model appears to be technically demanding and the investigators should be commended for this achievement. specific features of the model are associ- ated with limitations as well as opportunities that deserve further attention. first, a cuff was used to bridge the gap between the small calibre carotid artery and the larger aorta while at the same time facilitating the connection by avoiding sutures. the cuff, however, inflicts by itself an injury to the artery that leads to apoptosis of medial smooth muscle cell, adventitial inflam- mation, and subsequent intimal hyperplasia. in the setting of hypercholesterolemia, the cuff injury induces accelerated atherosclerosis. the mechanism of the injury is not com- pletely understood, but is likely related to an inflammatory response in the adventitia. in larger arteries, the endothelium seems to remain intact. using the most elegant technique of oct in the mouse stent model, no intimal thickening was observed in the cuffed area. in hypercholesterolemic animals, however, lesions are likely to form and potentially disturb flow patterns down stream in the stent area. second, the stented aorta is heterotopically transplanted into the carotid position of a recipient mouse and is in effect similar to an ex situ arterial interposition graft such as the radial artery graft in coronary bypass surgery. the perfor- mance of these grafts is usually quite good in spite of disruption of adventitial connections through vasa vasorum and nerves. however, graft intimal hyperplasia does occur in these bypasses, possibly as a result of transient ischemia during the procedure. in the mouse model, the syngeneic nature of the transplant and presumed immunologic responses may further stimulate neointima formation. if neointima grows in the nonstented segment of the aorta graft it can easily been mistaken for the candy wrapper effect observed in some endovascular therapies, most notably ionising radiation but occasionally also in the vicinity of drug eluting stents. as a transplant mouse model, the stented aorta also offers exciting opportunities. issues such as the involvement of circulating versus local cells can easily be studied. genetic and biochemical requisites of local and circulating cells can further be identified by using aortas from transgenic donors and/or place them in transgenic recipients. for instance, the novel model offers the potential to study the effect of individual genes on intimal hyperplasia, when crossing trans- genic mice in the apoe�/� background. third, the high incidence of thrombosis reported in this study is likely a result of the transplant procedure and the unusual anastomosis. if thrombosis really turns out to be related to the stent injury however, the model might serve as a worse case scenario to study interventions that aim to reduce the risk of thrombosis. finally, the stent and the recipient aorta are less than mm in diameter. stenting of small calibre arteries is associated with a higher frequency and degree of restenosis. in several trials artery size was an independent predictor of restenosis with arteries smaller than . mm in diameter being espe- cially at risk. this phenomenon has been attributed to a higher metal-to-artery ratio resulting in more vascular injury, hence more intimal hyperplasia. on the other hand the from the departments of physiology (m.j.p.) and cardiology (j.w.), carim, maastricht university, and the department of biomedical engineering (m.j.p.), technical university eindhoven, the netherlands. correspondence to mark j. post, md, phd, department of physiology, maastricht university, po box , md, maastricht, the nether- lands. e-mail m.post@fys.unimaas.nl (arterioscler thromb vasc biol. ; : - .) © american heart association, inc. arterioscler thromb vasc biol. is available at http://www.atvbaha.org doi: . / .atv. . .c editorial d ow nloaded from http://ahajournals.org by on a pril , favorable high shear stress conditions in the mouse aorta and carotid may balance the growth of neointima. although the influence of shear stress on intimal hyperplasia in stented arteries remains controversial, the relationship seems to be inverse in animal models, ie, increase in shear stress reduces intimal hyperplasia. allometric studies indicate that shear stresses in the mouse may be up to a factor higher than in humans, suggesting a favorable condition for stent patency. in summary, this novel stent model is a most welcome addition to many test tools available in vascular biology. disclosures none. references . ali zl, alp nj, lupton h, arnold n, bannister t, hu y, mussa s, wheatcroft m, greaves d, gunn j, channon k. increased in-stent steno- sis in apo-e knockout mice: insights from a novel mouse model of balloon angioplasty and stenting. arterioscler thromb vasc biol. ; : – . . lindner v, fingerle j, reidy ma. mouse model of arterial injury. circ res. ; : – . . courtman dw, cho a, langille l, wilson gj. eliminating arterial pulsatile strain by external banding induces medial but not neointimal atrophy and apoptosis in the rabbit. am j pathol. ; : – . . booth rf, martin jf, honey ac, hassall dg, beesley je, moncada s. rapid development of atherosclerotic lesions in the rabbit carotid artery induced by perivascular manipulation. atherosclerosis. ; : – . . wanders a, akyurek ml, waltenberger j, ren zp, stafberg c, funa k, larsson e, fellstrom b. ischemia-induced transplant arteriosclerosis in the rat. arterioscler thromb vasc biol. ; : – . . angiolillo dj, sabata m, alfonso f, macaya c. “candy wrapper” effect after drug-eluting stent implantation: deja vu or stumbling over the same stone again? catheter cardiovasc interv. ; : – . . roguin a, grenadier e. stent-based percutaneous coronary interventions in small coronary arteries. acute card care. ; : – . . kornet l, lambregts j, hoeks ap, reneman rs. differences in near-wall shear rate in the carotid artery within subjects are associated with dif- ferent intima-media thicknesses. arterioscler thromb vasc biol. ; : – . . greve jm, les as, tang bt, draney blomme mt, wilson nm, dalman rl, pelc nj, taylor ca. allometric scaling of wall shear stress from mice to humans: quantification using cine phase-contrast mri and com- putational fluid dynamics. am j physiol heart circ physiol. ; : h –h . arterioscler thromb vasc biol. april d ow nloaded from http://ahajournals.org by on a pril , material factor for the beauty of modern architecture decoration in harbin procedia engineering ( ) – - © published by elsevier ltd. doi: . /j.proeng. . . available online at www.sciencedirect.com available online at www.sciencedirect.com procedia engineering ( ) – procedia engineering www.elsevier.com/locate/procedia international conference on advances in engineering material factor for the beauty of modern architecture decoration in harbin he ying , liu songfu , sun quan * . school of architecture, harbin institute of technology ,harbin ,heilongjiang, china . the architectural design and research institute of hit, harbin,heilongjiang, china abstract to conduct an in-depth research on the outstanding performance of architecture decorative material in the areas of technology and art at certain historical times, this article mainly studied the modern architecture decoration in harbin. we did a survey on the decoration of modern buildings in harbin, and comprehensively studied the construction and artistic performance of materials used to decorate the modern buildings, such as woods, bricks, stone, plaster and iron, from the perspective of traditional art and technological philosophy, from which we found the important role of materials playing in the process of sculpturing the beauty of architecture decoration. the material factor of architecture decoration is a substantial foundation for the existence of architecture beauty, and reflects the traditional concept of different schools and culture in the areas of architecture materials and constructive technology. © published by elsevier ltd. selection and/or peer-review under responsibility of icae . key words：modern architecture in harbin, wood decoration, bricks, stone, plaster, iron processing the basic structure of modern architecture in harbin consists of wood, brick and ferroconcrete. woods, bricks and stone are the main materials for decorating the architecture, and plaster decoration is commonly for the external side of the architecture. the “new art” campaign in harbin popular in this period initiated traditional handicraft, so the decoration of architecture commonly took the iron decorative elements as the first choice, which was perfect combination of technology and art for decoration. the decorative materials mentioned above outstandingly reflect the unique beauty of modern architecture decoration through different construction technique according to their own characteristics, and add unique appreciation value to the architecture of this emerging city in modern times. . simple wood decoration * corresponding author. tel.: ; fax:. e-mail address: heying@guigu.org. open access under cc by-nc-nd license. open access under cc by-nc-nd license. http://creativecommons.org/licenses/by-nc-nd/ . / http://creativecommons.org/licenses/by-nc-nd/ . / he ying et al. / procedia engineering ( ) – he ying, liu songfu, sun quan/ procedia engineering ( ) – wood is a kind of natural material, which can be applied to the partial decoration of the architecture after being processed by artisans. it’s a unique material language praising simple architecture and the beauty of nature. in modern times, the decoration of traditional architecture of the russian nation in harbin commonly preferred wood as well. the history of russian architecture said, the solemn nature of the north, the simple technique and the only material (wood) urged the architects to find a way to show the artistic and splendid buildings in decoration and furnishing, and they had also deliberated on the proportion in composition of the external volume, the beauty and the balance of the sketch. therefore, the architecture with wood decoration represented remarkable classic and profound reality. figure the orthodox cathedral of st nicola figure the cathedral of st nicola the orthodox cathedral of st nicola at nan gang centre, the highest geological site in harbin, was the paragon of wood architecture in this period. this was the first large architecture project of “east moscow” and the centre of the lama square, which is the harbin museum square now. (figure ) the exquisitely carved wood decorations are some details of this kind of style, such as the wood stairs with exquisitely carved double slope roof crossing into the flame shape of an arch, at the centre of which is the elegant wood flower, at the entrance of the cathedral. (figure ) figure traditional wood residence of the russian nation figure partial wood decoration of independent residence the traditional independent architectures of the russian nation in harbin, such as the independent residence at jiangbei garden street (figure ), also commonly take woods as the decorative materials, which represents the traditional decoration of the russian nation and expresses the culture of folk art and romanticism. besides, some independent houses would use wood to decorate the balcony and the door handle. (figure ) . simple brick decoration in modern times, the brick was a widespread architecture material in harbin city. according to the research on modern buildings, . % of them were constructed with bricks. figure - traditional brick residence of the russia（）figure - traditional brick residence of the russian （） he ying et al. / procedia engineering ( ) – he ying, liu songfu, sun quan/ procedia engineering ( ) – in the early stage, most of the brick architectures were the residential blocks for employees of the middle east railway, which consist of brick wall and one-store double slope roof which was made by wood. these buildings are located at the central area of nangang town, harbin province, becoming a side-by-side building zone. all of their external walls are brushed in the colors of butter yellow and white, thus having achieved the artistic effect of overall coordination and brought people fresh feeling. (figure - and figure - ) figure the original amur military command there are various kinds of public architectures in early stage such as business schools, hospitals, clubs, supermarkets, etc. compared to residence for employees of the middle east railway, the wall and the cornice with brick decoration of these public architectures are far more various. the original amur military command (figure ) which is the chinese medicine hospital of heilongjiang province now and the original pharmacy of middle east railway hospital which is the emergency centre of no. hospital of harbin medical university (figure ) are typical buildings of this kind. the most distinguishing characteristic of the architecture decoration is concave and convex changes at the cornice. figure the original pharmacy of middle east railway hospital figure the st sophia church figure the church of st alexeyevfigure the church guarded by st mother besides, the brick construction was also popular among some grand russian orthodox churches of harbin in modern times. according to the finishing time, st sophia church (figure ), the church guarded by st mother (figure ) and the church of st alexeyev (figure ) were some of the examples. the brick decoration for the external wall of these churches was various and clear in molding in order to stress the integrated feeling of the churches and show us the carved potential of bricks, just like the churches mentioned above. . the natural stone decoration he ying et al. / procedia engineering ( ) – he ying, liu songfu, sun quan/ procedia engineering ( ) – stone is the traditional material of west architecture. there are less stone to be exploited in the north area of china, and the cost is very high. therefore, in modern times, the only architecture with stone decoration in harbin was the original office building of middle east railway bureau which is the office building of harbin railway bureau now. (figure ) the office building of middle east railway bureau located at the west street of nangang area in harbin was constructed in , which was the first grandest public architecture in harbin. the wall of the architecture was constructed with thick granite. to enclose and stabilize the architecture, large pieces of granite were arranged regularly and it was decorated with smoothly straight wall corner, highlighting the natural beauty of stone decoration. (figure - and figure - ) figure the original office building of middle east railway bureau figure - the original office building of middle east railway bureau ( ) figure - the original office building of middle east railway bureau ( ) . the splendid plaster decoration plaster means the gypsum slurry decorative art and using lime mortar, mixed mortar, polymer mortar, hemp fibred mortar and paper strip mixed lime mortar to decorate the surface layer of the architecture. the architecture ten book describes it like this: the architecture is plastered with mortar with the help of ruler. the ruler and the wire help determine the length, and the hammer is used to adjust the height. when it comes to the corner, we use the square ruler. in this way, the mural on the surface will be perfectly suitable. then repeat for the second and third time after it is dry. by doing so, the mortar layer will be solider and solider and the wall will be strengthened as time goes by. figure decorative plaster in the buildingfigure "chinese baroque" decorative plaster for the external decoration of modern decoration in harbin, plaster was the common material as well. it provided different decorative theme to the parapet, columns and windows of the architecture, showing the substantial content of plaster decoration and different types of artistic character. (figure ) apart from the specific decoration form of architecture, various types of potential of plaster can be also reflected in the details of architecture decoration. for example, the horizontal line feet of the doors, windows and walls are the result of deeply deliberating on the proportion and decorative effect of the architecture. (figure ) . the pliable iron process he ying et al. / procedia engineering ( ) – he ying, liu songfu, sun quan/ procedia engineering ( ) – the “new art” architecture in harbin was a school based on trying to make the architecture accustomed to and improving the industrialized idea in modern times. to pursue the new style of modernization and be accustomed to needs of the new society, the architecture decoration introduced some pop artistic techniques and materials. one decorative trait of new art architecture was taking the iron processing parts as the architecture. the parapet, the railing of the balcony, the door handle and the canopy at this period preferred the iron processing parts as well. (figure ) the traditional architecture parts were replaced by various iron decorations, which added to vitality of modern architecture for their flexibility and represented the progress of modern architecture in decorative material. figure iron decorations in the building . conclusions we found the relationship between materials of architecture decoration and the beauty of form through the study in this article. firstly, all kind of materials comply with their own destiny. in other words, they should fulfill their duties in some certain form. they have integrated colors and textures. secondly, materials are not chosen for easy treatment or satisfying life needs. last but not the least, the form of material has enlightened, underlined and multiplied some other forms at the stage of raw material, because the form can free the other form according to its own law. however, the formal duty of material is not blind fatalism, for the reason that the rich kinds of materials are individual and suggestive. reference [ ]zhu guangqian. art history in the west, beijing: jincheng publication, [ ]hagel. the aesthetics. translated by zhu guangqian. beijing：business publishing house， [ ]zhang fuhe. the study of modern history of china in century, central china architecture, ( ) [ ]ren guangxuan, art history of russian. beijing university publication, [ ]focillon. form of life. translated by chen ping. beijing university publication， [ ]paul greenhalph. art nouveau - .v&a publication, [ ]elena borisona, grigory sternin. russian art nouveau. rizzoli new york, [ ]willarm jr curtis. modern architecture since .phaidon oxford, [ ]david dernie, alastair carew-cox. victor horta.academyeditions, [ ]david wolff. to the harbin station: city building in russianmanchuria, - .california univercity, e.xps middle-east journal of scientific research ( ): - , issn - © idosi publications, doi: . /idosi.mejsr. . . . corresponding author: abdul highe khan, faculty of economics and management sciences, international islamic university malaysia, malaysia. what makes tourists satisfied? an empirical study on malaysian islamic tourist destination abdul highe khan, ahasanul haque, muhammad sabbir rahman* faculty of economics and management sciences, international islamic university malaysia, malaysia graduate school of management, multimedia university, malaysia abstract: the main objective of this study is to explore influential factors that lead to tourist’s satisfaction in destination based islamic tourist destinations in malaysia. this research is necessary to provide a better understanding of the muslim tourist satisfaction in malaysian islamic tourist destination in the different facets. the identification of influencing factors that make muslim tourist satisfied help islamic destination marketer to make strategic marketing plans. multiple regressions was employed to identify the relationship among the variables. from the analysis it was found that destination image, religious motivation and service quality have a positive relationship with tourist satisfaction on islamic tourist destination in malaysia. key words: destination image religious motivation service quality islamic tourism tourist satisfaction malaysia introduction previous time many research conducted in islamic tourim tourism industry is evidently a large international saudi arabia [ , ] and found that islamic tourism is industry with huge potential for growth. it is becoming an popular among muslim tourists. the purpose of this increasingly global and complex phenomenon with research is to identify the factors that influence muslim sociological, behavioral, economic, political, cultural, tourists to opt for islamic tourism. there are many islamic environmental and educational dimensions. for many tourist destinations in malaysia and every year countries, tourism is an increasingly important source of thousands of muslim tourists come to malaysia to visit income, employment and wealth. robinson [ ] considered those destinations. despite this, there remains a little tourism to be the ‘largest of multi-national activities’ research gap to identifies the factors that influence which accounts for a larger share of foreign exchange muslim tourists and their choice of islamic tourism receipts and export earnings than any other industry. destinations. sheller and urry [ ] added that tourism is the largest industry in the world and emphasized the mobility materials and methods produced by tourism in that it affects almost everyone everywhere. destination image: destination image is an essential there are islamic countries with many tourist factor to encourage tourists towards any destination [ ]. destinations. the organization of the islamic conference if any destination management can create positive images (oic) is the governing body charged with maintaining of the destination, number of tourists will increase [ ]. relations between muslim countries. among its agendas a strong destination image gives a competitive advantage is to promote islamic tourism among muslim countries.in over competitors [ , ]. destination image influences the in many countries such as malaysia, palestine, iran and middle-east j. sci. res., ( ): - , decision making process of the tourist. if the tourist has their service, managers can satisfy their tourist and make a positive perception of the destination then they are tourist loyal to the destination [ ]. according to sparks likely to visit [ - ]. and westgate [ ], poor service quality hampers the destination image plays an important role in potentiality of that business and influences customers to choosing the tourist destination. a positive destination switch service providers. this premise is applicable to the image enhances the probability of greater tourist numbers tourism industry. if any particular tourist destination fails [ , ]. according to baloglu and mccleary [ ], to provide quality services then customers will choose destination image in tourist industry has three categories other destinations [ ]. ( ) cognitive factors: the estimation of site selection of the tourist, ( ) affective factors: perception and attitude tourist satisfaction: tourist satisfaction is related to the towards the destinations and finally ( ) conative factors: mental state of the tourist rather than the physical state. the selected destination. tourists can notice their satisfaction when he or she religious motivations: motivation plays a significant satisfaction refers to the pleasure of the tourist after role in travelling. travelling motivation refers a set of visiting any particular tourist destination. tourist measure interests that influence a tourist to travel. tourists may satisfaction by comparing the expected service with the travel for recreation, social status, culture, spiritual actual service of the destination [ , ]. tourist purposes [ ]. two motivational factors influence satisfaction leads to repeat visits and a positive image tourists to visit any destination, pull motivational spread through word of mouth. a positive image shared factors and push motivational factors [ , ]. through word of mouth between tourists increases the push motivational factors are related to internal aspects number of tourists visiting a certain destination [ , ]. of the tourist, for instance economic condition, social status, demographic factors such as education level, age, destination image and tourist satisfaction: destination occupation, gender and income [ ]. on the other hand, image has a positive influence on tourist satisfaction. pull motivational factors are external aspects of tourism if tourists perceive positive image for any destination in that attract tourists to travel such as travelling time and their mind, then they will be satisfied easily. a better cost [ , ]. destination image provides mental satisfaction of a given there is a close relationship between tourism and destination [ , , ]. mohamad et al. [ ] conducted a religious motivation. henderson [ ] found that some research in malaysia and found that destination image is tourists are religiously motivated to visit religious one of the important antecedents for tourist satisfaction. destinations. religious destinations refer to any event, during the world cup football, lee et al. [ ] led a religious festival, or memorable place. he also found that research on destination image of korea. based on the religious tourism gives tourist mental and spiritual study, they concluded that destination image was one of benefits. in islamic tourism, muslims do not just visit the essential antecedents of tourist satisfaction on places; rather they seek the mercy of allah s. w. t. korean tourist destination. for instance, during the hajj and umrah pilgrimages, the main success of any destination depends upon muslims are satisfying one pillar of the five pillars of the level of satisfaction of tourists [ , ]. chen and tsai islam. during traveling of their pilgrimage, muslims [ ] and found a close relationship between tourist tourists often visit islamic historical places [ ]. destination image and tourist satisfaction. research has visiting such places can be a form of relaxation and proven that the main attraction of a tourist service is the educate muslims of the history of islam [ ]. destination. chi and qu, [ ] confirmed that there are service quality: according to zeithaml and bitner [ ], destination image is a significant factor. without building service quality is the customer’s judgment of the a positive destination image on tourist mind, it is difficult standard or quality of the service. service quality is the to make any single tourist satisfied. based on the heart of the business prosperity of the service industry literature, this study proposed that: [ ]. better service quality brings more customers and generates more revenue. it is in the interest of the h : there is a positive relationship between destination managers of every tourist destination to be concerned image and tourist satisfaction with improving the quality of their services. by improving religious motivations and tourist satisfaction visits their favorite destination [ , - ]. tourist many factors that lead to tourist satisfaction but tourist supti note motivation destination image religious motivation service quality tourist satisfaction middle-east j. sci. res., ( ): - , there is a close relation between tourist motivation the conceptual research model of this study: and satisfaction. beerli and martín [ ] mentioned that motivation is the need that drives an individual to act in a certain way to achieve the desired satisfaction. according to yoon and uysal [ ], tourist satisfaction works as a mediator between travel motivation and tourist destination loyalty. valle et al, [ ] also found a similar result. in the context of islamic tourism, it is obserbed that thousands of muslim tourists visit islamic tourist figure : the proposed model of tourist satisfaction destination in malaysia. based on that it can assume if tourists have religious motivation to visit islamic tourist questionnaire. after modifying questionnaire we destination, then there is a chance to be satisfied. for this distributed questionnaires at various islamic tourist reason this study proposed that: destinations in selangor and kuala lumpur, this research h : there is a positive relationship between religious procedure. respondents were informed about the purpose motivation and tourist satisfaction of the research before distributing the questionnaire. service quality and tourist satisfaction data collected from different islamic tourist destination service quality has been associated with customer each of the named items was measured using a five satisfaction. service quality is the overall valuation of point rating scale ( = strongly disagree; = disagree; service. not only are core products or services evaluated = neutral; = agree; and = strongly agree). but all supporting services as well [ - ]. customers with after examining the questionnaires, this research kept positive views of service quality are likely to be more only those questionnaires that were fully completed by satisfied compared to other customers [ - ]. the respondents. for the successful completion of this better service quality of destination attracts tourists research this study has rejected questionnaires and and leads to greater tourist satisfaction. according to has kept questionnaires for analysis. kumra, [ ], tourist satisfaction is the final outcome of better service quality. kumar’s study of rural tourism in result and discussion india led him to assume that service quality of indian tourist destinations satisfied both local and international to analyze the data, statistical package for the tourist. lee [ ] directed research in taiwanese tourist social sciences (spss) version software was destinations and stated that the taiwanese tourist used. descriptive analysis was conducted to find department satisfied tourists by offering excellent service out the demographic background of the tourists. quality. the study of olsen [ ] indicated that superior the demographic part comprises of gender, age, marital service quality brings about customer satisfaction which status, country, academic qualification, profession, results in customer loyalty. it is not easy to achieve monthly income, number of visitation in malaysia, name customer satisfaction and loyalty. better service quality of destination visited. in terms of respondent’s gender, enhances the chances to achieve customer satisfaction table shows that % of respondents were male and and loyalty. this study like to test following hypothesis: % were female. the classification of samples in terms of h : there is a positive relationship between service single, % respondents were married. in case of quality and tourist satisfaction respondents age huge number of respondents are research methodology: to accomplish research, we percent. the second highest percentage of respondents generated items from three independent variable belong to age are and above. this group represents (destination image, religious motivation and service percent. quality) and dependent variable tourist satisfaction. almost half of the respondents ( percent) monthly we used pilot study with respondents from income is $ to $ , followed by percent different islamic tourist destination in malaysia. respondents monthly income is between $ to $ . during pilot testing, some mistakes were observed in the whereas percent respondents’ monthly income is were employed a survey via convenient sampling in malaysia in june to august . in addition, their marital status presents that % of respondents were between to years old. their percentages are middle-east j. sci. res., ( ): - , table : demographic profile of the respondents table : reliability analysis and factor loading descriptions frequency percentage cumulative (%) gender: male female . age: below - - and above . marital status: single married . country: middle east asia europe africa america . table : demographic profile of the respondents descriptions frequency percentage cumulative (%) profession: student job holder business owner academician home maker (housewife) . income: below $ $ -$ $ -$ $ and above . number of visitation in malaysia time st time nd time rd time and above . th table : kmo and bartlett’s test parameters value kaiser-meyer-olkin measure of sampling adequacy . bartlett's test of sphericity: approx. chi-square . df sig . above $ . percent tourists are business owner, followed by percent job holder, . and percent respondents were academician. it was the first time visitation for most of the respondents ( percent) and percent respondents visit for the second time. among the popular islamic tourist destination of malaysia, most of the respondents ( . percent) visited national mosque of malaysia (masjid negara), located in kuala lumpur. second most visited destinations were putrajaya mosque in federal territory putrajaya with . percent. factors loading cronbach’s alpha destination image . di . di . di . di . di . religious motivation . rm . rm . rm . rm . service quality . rel . res . res . emp . rel . emp . tan . table : coefficients standardized significance hypothesis coefficient (beta) (p value) remarks destination image . . supported religious motivation . . supported service quality . . supported dependent variable: tourist satisfaction reliability analysis: to test the goodness of all variables in the test reliability analysis using the chronbach’s alpha coefficient. cronbach’s alpha was chosen to analyze the degree of consistency among the items in a construct. hair et al., [ ] mentioned that the cronbach alpha should be at least . for the results to be deemed as reliable. in this study the value for each variable is above . and it indicates that the variables are reliable. the result of reliability analysis is given below. exploratory factor analysis (efa): generally a higher factor loading specifies the stronger affiliation of items to a specific factor. the findings of this research indicate that items of each of the three ( ) variables namely, destination image, religious motivation and service quality were homogeneous. one item is close to another item. on the other hand the reliability coefficients of those three factors are: destination image (. ), religious motivation. ( ), service quality (. ), respectively. on the other hand kmo index and bartlett’s test of sphericity weighed the suitability of the data. according to [ ], the kmo value should be higher than . . for this reason the factor loading for all items middle-east j. sci. res., ( ): - , exceeding the minimum value of . were considered in the significant value is smaller than alpha at . and this study. from the analysis we found our kmo value hypothesis is accepted. result of this study supported is . . beside that the results of bartlett’s test of similar study in other countries, confirm a positive sphericity are all significant (p= . ). factor analysis relationship between service quality and satisfaction in also confirmed that the construct validity of the scales tourism industry [ - ]. could be performed adequately. those items that did not meet the requirement and that were dropped are conclusion and direction of further study: destination image , religious motivation , religious this empirical study provides evidence that destination motivation , tangibility , assurance and assurance image, religious motivation and service quality of tourist of service quality. destination is closely associated with satisfaction of the hypothesis testing: the causal relationship of the economy of malaysia, it can be say that major findings of constructs was assessed using regression analysis as this study have significance for policy and managerial summarized below. implications for the country’s core islamic tourist hypothesis : destination image has a positive fundamental in extending length of stay, increasing relationship with tourist satisfaction satisfaction and enhancing destination loyalty of foreign the results of this study show that the association importance of religion motivation to choosing tourist between destination image and tourist satisfaction is destinations; especially its relation with destination image supported. the multiple regression result shows and destination loyalty. destination image has a beta of . and significant p the study suffers from a number of limitations. even value is . . the significant value is less than alpha at though the results are interesting and support previous . and hypothesis is accepted. therefore proposed studies, there were some limitations. hence, the results hypothesis is supported. this findings supports the cannot be easily generalized. first of all, this study used previous similar study [ , , - ]. convenience sampling procedure which is a limitation. hypothesis : religious motivation has a positive procedure with more samples. on the other hand the efa relationship with tourist satisfaction is difficult to generalize to a larger audience and there was the association between religious motivation investigation, so the quality of questionnaire cannot be and tourist satisfaction is supported in this study. ensured. the multiple regression result shows religious motivation has beta of . and significant p value is . . references the significant value is less than alpha at . and hypothesis is accepted. previously some researchers also . robinson, m., . cultural conflicts in tourism: found close relation between tourist travel motivation and inevitability and inequality. in robinson, mike and satisfaction. beerli and martín [ ] recommend that boniface, priscilla (eds) tourism and culture motivation is the need that drives an individual to act in conflicts. wallingford, ct (cab international). a certain way to achieve the desired satisfaction. . sheller, m. and j. urry, . tourism mobilities: according to yoon and uysal [ ], tourist satisfaction places to play, places in play (london: routledge). work as mediator between travel motivation and tourist . bhuiyan, m.a.h., c. siwar, s.m. ismail and r. islam, destination loyalty. . the role of government in ecotourism hypothesis : service quality has a positive regions. j. soc. sci., : - . relationship with tourist satisfaction . farahani, h.z. and j.c. henderson, . islamic the relationship between service quality and tourist islamic societies: the case of iran and saudi satisfaction of islamic tourist destination is also arabia. international journal of tourism research, : positive. the multiple regression result shows service - . quality has a beta of . and significant p value is . . . hankinson, g. . the brand images of tourism destinations: a study of the saliency of organic images, journal of product & brand management, vol. 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( ). is small always beautiful? a dialogue. business and society review, ( ), - . https://doi.org/ . /basr. peer reviewed version link to published version (if available): . /basr. link to publication record in explore bristol research pdf-document this is the author accepted manuscript (aam). the final published version (version of record) is available online via wiley at https://onlinelibrary.wiley.com/doi/full/ . /basr. . please refer to any applicable terms of use of the publisher. university of bristol - explore bristol research general rights this document is made available in accordance with publisher policies. please cite only the published version using the reference above. full terms of use are available: http://www.bristol.ac.uk/red/research-policy/pure/user-guides/ebr-terms/ https://doi.org/ . /basr. https://doi.org/ . /basr. https://research-information.bris.ac.uk/en/publications/ ad a - - ef-af b- b a e e cd https://research-information.bris.ac.uk/en/publications/ ad a - - ef-af b- b a e e cd is small always beautiful? a dialogue for quite a few years, but in a very intermittent manner, the two authors have been engaging in dialogues about management issues. so far, they have been concerned with business ethics, capitalism, alternatives to management, and management education (parker and pearson , ; pearson and parker , ). this all started when we were teaching business ethics together at keele university, england in the mid- s, and we found that debating our differences in class, in front of the students, seemed to be a good way to teach. thinking about plato’s dialogues between socrates and his various students, we liked the way that he would clarify the nature of a concept by asking questions and listening carefully to the answers, and we decided we would try and do the same. we disagree about many things, but agree that we respect each other’s opinions, and can clarify our own viewpoints by debating them respectfully with another. for the reader to find this format engaging, you might like to know something about the two characters who are staging their disagreement here. gordon spent around thirty years in various companies, mostly with responsibilities for strategy. he then completed a phd studying innovation, strategy and culture and joined academia. he is convinced, along with sumantra ghoshal, that bad theories have corrupted good management practices (ghoshal, ) and should be set aside in favour of the lessons provided by practical experience (pearson ). martin, on the other hand, has spent most of his working life as a ‘critical management studies’ academic and believes that imagining alternatives to market managerialism is ethically and politically important (parker , parker et al , ). he agrees that business schools often teach bad theory, but thinks that means we need to teach better theory. the two participants below might be characterised as a ‘practitioner idealist’ (gordon) and an ‘academic idealist’ (martin). for this dialogue, we decided to focus on the question of the scale of business operations. martin has a particular preference for small scale enterprise, and for the localisation of the economy, because he believes that the giganticism of corporations is behind many of the problems we face today. as you will see, gordon disagrees, arguing instead that other issues than scale are at the root of why some businesses do bad things. the dialogue ‘how then can we rightly order the distribution of the land? in the first place, the number of the citizens has to be determined, and also the number and size of the divisions into which they will have to be formed; and the land and the houses will then have to be apportioned by us as fairly as we can. the number of citizens can only be estimated satisfactorily in relation to the territory and the neighbouring states. the territory must be sufficient to maintain a certain number of inhabitants in a moderate way of life - more than this is not required; and the number of citizens should be sufficient to defend themselves against the injustice of their neighbours, and also to give them the power of rendering efficient aid to their neighbours when they are wronged. after having taken a survey of theirs and their neighbours' territory, we will determine the limits of them in fact as well as in theory. and now, let us proceed to legislate with a view to perfecting the form and outline of our state. the number of our citizens shall be - this will be a convenient number; and these shall be owners of the land and protectors of the allotment.’ plato laws, book five. martin: plato’s dialogue laws is the only one not to feature socrates. like the much better known book the republic, it concerns the ideal forms of government for a state, including the discussion of scale above. plato liked the number , because it was divisible by many other numbers, and it seems to produce a pleasing sense of proportion. for our purposes here, it is important to point to the fact that plato appears to be concerned with the maximum size that a city should be in order that it can meet its responsibilities to its citizens and its neighbours. even if his definition of citizen excludes women and slaves, he seems to have the intuition that there is a relationship between the number of people entangled in a social institution and the quality of their interactions. now, when ordinary people say that they have responsibilities, it suggests choices. we choose to shoulder burdens, to care, because we feel that we must, because it involves people that we love, or causes and values that we care about. not to respond, to ignore a call to duty, would result in guilt and shame, in a judgement of self which is experienced as a kind of pain. responsibility is a personal question that requires an answer, a relationship which is felt in the body of human beings when they engage with issues that we can describe as ‘ethical’, ‘moral’ or even ‘political’. but when an organization – a corporation - claims responsibilities, what might that mean? if it was a small business, a bakery perhaps, with customers with faces and names and who come in on regular days for particular kinds of bread, it would make sense to say that the owners, the baker, or the shop assistant might feel responsibilities. i suppose we might say the same for plato’s community of families, though that does already seem like quite a large number of people to care about. however, if we consider bigger organizations or states, though they can claim to care, and very often do make such claims, it is difficult to imagine exactly what that might mean. an organization (as such) can’t speak, can’t see, can’t feel (silverman ), so the language of responsibility can only be metaphorical, a phrase intended to produce certain effects. it seems to me that scale and responsibility are opposed. the bigger an organization, the more people it employs and the more countries it trades in, the more irresponsible, the more sociopathic its behaviour is likely to be. this is not a new suggestion (bakan ), but it is one that is gaining particular urgency now, as it becomes clear enough that big commercial organizations are engaged in a systematic avoidance of responsibility at the same time that they loudly claim to care about people and planet (hadden et al ). that is why i propose, echoing plato, that we should limit the size of all organizations in order to ensure that social responsibility means something, rather than being a phrase employed with shrill intensity in order to persuade others of corporate virtue. i would do this by preventing any organization owning another as well as breaking up large corporations in order to produce a population of smaller organizations which can do less damage, and are forced to take human scale responsibilities more seriously. small is obviously more beautiful, when it is clear that giganticism causes such damage (schumacher ). gordon: i’m sure we can both of us agree to forgive plato his odd liking for the number and his limited relevance to the st century corporation. as i have suggested before, i fail to see how ancient philosophy can be particularly useful in solving contemporary business problems (pearson and parker ). that being said, i imagine we might also agree that the mass production cost savings justification for large scale is no longer as persuasive as it used to be and seems likely to become even less so. moreover, i agree wholeheartedly with you that ‘imagining alternatives to market managerialism is ethically and politically important’, particularly when so many business schools just teach their mba students the virtues of self-interest. and finally, i’m sure we also agree that ‘too big to fail’ and ‘too big to manage’, where they apply, are persuasive arguments against large scale. big is not always beautiful. i hope that has got all the agreements out of the way, because there is a lot that i disagree with! you recognise responsibility as a personal ‘ethical’, ‘moral’ or even ‘political’ question that only an individual can actually feel and therefore exercise. at one level, you might be right, but good management is very much to do with the establishment and maintenance of an organisational culture which defines ‘the way we do things around here’ (bower, ). the organisation may not be able to feel, but all the people in it can, and in a well-managed organisation people will be aware of the relevant cultural norms. that applies to the small corner shop bakery, the high tech sme employing a few hundred people, or to a leviathan mass employer such as j p morgan chase which has, since , paid tens of billions of dollars in fines for criminal fraud. organizational culture is the issue here, not size. all big organizations are not evil and all small ones are not saints. martin: size isn’t the only issue, but it is a critical one. the endearingly vague concept of organizational culture is far too easily used as a distraction in this regard, a way of refusing to make any hard decisions about policy or structure. for quite a while now, it has been common for commentators and regulators to talk about culture. ‘changing the culture’ is essentially a way of doing nothing, apart from issuing some codes or guidance which seem to be an attempt to tell regulators and customers that it won’t happen again. so when the uk bank barclays, in early , decided to be seen to be doing something, they produced a website which summarised ‘our values’, which were summarised as respect, integrity, service, excellence and stewardship. there was talk of quaker traditions, and restoring the trust of customers and citizens. this all sounded very nice, but a few months later the bank was exposed as being involved in the ‘dark pool’ fraud which favoured some investors over others. this particular scandal followed others – in barclays and just about every other london based bank – which are simply too numerous to mention. the bank also announced in may that it would shed thousand jobs, at the same time that the basic salary of its chief executive exceeds £ million per year. to his credit, he did turn down his bonus of an extra £ . million in , only taking £ million of shares instead. ‘culture’ does matter, because not all big organizations are criminal and not all small ones are responsible, but there are other factors that matter more. unless we cut big organizations down to size, unless we change the inhuman structures that corporate business inhabits, we establish the conditions which encourage reckless and irresponsible behaviour, whatever they say on their websites. gordon: culture is real; not just a distraction. unlike you, i’ve lived it in both medium sized and very large organisations and it can be extremely important. the waffle about culture to which you refer, is not just ‘window dressing’, but deliberate lies intended to mislead. that’s not culture; that’s plain deceit which disguises the real culture. when you refer to banks, you are often referring to criminal organisations. almost without exception among the leading players in the global markets, they have paid hundreds of millions of dollars and pounds in fines for their criminality. your example, barclays, appointed bob diamond, mba, as ceo after he had presided over the libor interbank rate fixing scandal, for which barclays paid £ million fine rather than risk bob being charged personally. when bob was eventually forced to resign, barclays gratefully paid him a £ m goodbye fee. that was not caused by size, but by corruption and poor decision making. or, to use another example, at the end of , the duke of york hosted j p morgan and clients for dinner and entertainments at buckingham palace. that was only days after morgan’s agreed settlement of their $ billion fine for fraud and criminality, with ceo jamie dimon, mba, even then, under criminal investigation. morgan’s settlements, in lieu of criminal charges, now total over $ billion. the latest being over $ . billion when they joined ubs, citigroup and royal bank of scotland being fined ‘for currency manipulation and collusion-like efforts on the part of the financial institutions’ (cummans, ). as you say, the examples of banks criminality are ‘too numerous to mention’. but the problem is not size but the practices of those who run these organization. so a solution is not to be achieved by simply arbitrarily reducing the size of these banks, as if that might ensure that only the saints were left in charge. there’s something much deeper than that which needs correction. martin: your logic puzzles me here. all the examples you have used are of big organizations, but you continue to insist that the problem is culture. so, let’s make a list then - enron, parmalat, tyco, union carbide, worldcom, tesco, ford, general motors, glaxosmithkline, arthur anderson, m g rover, siemens, american airlines, bae systems, firestone tire, global crossing, guinness, halliburton, southwest airlines, royal dutch shell, volkswagen and so on, and so on. all of these large companies (and the list could have gone on for pages) have been involved in scandals of various kinds – from hiding losses to stealing money to disguising the characteristics of their products – and none are banks. now i suppose we could say that they all had a bad culture, but in which case i think we have to explore the idea that there might be a relationship between culture and scale. that is to say, that the bigger the organization, the easier it becomes to avoid responsibilities – whether to employees, shareholders, customers, the environment or whatever. so, are you prepared to acknowledge that ‘culture’ is (in part at least) a function of scale? gordon: of course, scale impacts on culture, but culture isn’t the problem. i referred to culture as part of a solution. let’s put culture aside for the moment. there is something much more important, much more dangerous, than ‘giganticism’ underlying the criminality of corporate abusers. size is itself a red herring. the only reason your above list includes only the corporate leviathans is because smaller company abusers don’t hit the headlines in the same way. in that sense, your outrage is merely a result of bad sampling rather than proper research. but smaller companies can be just as crooked as big companies, if not more so. i know this because i’ve seen it. many years ago i worked for a medium sized company whose chairman, among other things, had his holiday cottage re-roofed at company expense and his domestic heating bills paid by the company, and he was at the time a regional chairman of the confederation of british industry. his fellow directors tended to follow his example. as another example, i provided a factual running history of one small company abuser, s.t.p. ltd, in my book, the real business of real business (pearson, ). size really is not the crucial point, though multinational operation certainly opens up new opportunities for criminality which require particular regulatory attention. simply attributing corporate criminality to size and the impossibility of managing such leviathans ends up by absolving those who hold that responsibility. it makes them into pawns of social structures, puppets having their strings twitched by others. but they are responsible. that is not to suggest they are necessarily villains by birth or inclination, but they act as criminals. the big question is ‘why?’ asserting that it is because their organisations are so big is simply not a necessary or sufficient explanation. martin: let’s agree that all sorts of people behave badly, both the corporate ceo and the owner of my local bakery. i’m not trying to suggest that saints run smes and sinners run corporations – though let’s come back to that later - but consider the relative impact of each. if a private company bidding for contracts with the tax payer funded uk national health service avoids paying tax through using a network of offshore holding companies, it means that the uk taxpayer loses millions. if a private bank has to be rescued in order to ensure its responsibilities to account holders, the uk taxpayer can lose billions. if your business person plays fast and loose with their ‘expenses’, the taxpayer might lose thousands. if my bread shop under reports their profits, the taxpayer might lose hundreds. my point is that big organizations cause a lot of damage when they behave badly, which it seems to me that they very often do. but let me clarify something. you suggest that ‘culture isn’t the problem’ (though you do suggest it’s ‘part of the solution’), so does this mean that you are going to try and claim that it’s all about a few bad apples? a few naughty people who spoil things for the rest of us? gordon: absolutely not. the few bad apples argument is only ever raised to protect the status quo by pretending there’s nothing basically wrong. i am suggesting there’s something ‘profoundly wrong’. that was tony judt’s expression at the start of his final book ill fares the land: ‘something is profoundly wrong with the way we live today. for thirty years we have made a virtue out of the pursuit of material self-interest: indeed, this very pursuit now constitutes whatever remains of our sense of collective purpose.’(judt, : ). that’s the problem, not size. i agree if an organisation goes rogue, then the bigger it is the more damage it is likely to do. but the problem is organisations, even whole industries, going rogue, rather than their size. we’ve already highlighted banking as the prime example. between and , the twelve global banks paid out £ . bn worth of fines to european and us regulators for various criminal offences, and made provisions in their accounts for a further £ . bn of anticipated fines for crimes which presumably they know all about, but which have not yet been uncovered. even that ‘eye popping’ figure of £ bn, was ‘unlikely to be the final hit’ (tett, ). according to reuters the top banks have paid fines of $ billion over the past seven years for criminal behaviour (treanor, ). that’s the problem. in may , the us department of justice ruled on bank manipulation of foreign exchange dealings. with what us attorney general, loretta lynch, described as ‘breathtaking flagrancy’ of ‘brazenly illegal behaviour’ on a ‘near-daily basis’, traders had set up a forex control group they themselves referred to as ‘the cartel’. the simple aim was to defraud clients by collusion to fix prices. as one widely quoted trader put it: ‘if you ain’t cheating, you ain’t trying.’ but it hasn’t always been like this. banking was necessarily built on trust. in order to function, it needed to be seen as the most proper of industries and that itself regulated behaviour. but nowadays it sets a routinely criminal example. that example has been followed by some other industries where participants believe that they can get away with it, having managed to eliminate the former soft and hard forms of regulation in order to maximise the possibility of profits. consequently many mature markets are now ‘fixed’ by monopolistically inclined leading players. they may be big, but their size is not the reason that they behave as they do. the problem is the widespread willingness, even eagerness, to act criminally. my argument is that it is the ‘bad theory’ that explains and even to a great extent justifies that behaviour. you, as an academic idealist, a professor of management, should be challenging that theory, rather than making a misguided general tilt at the badness of scale. martin: interesting. you are quite happy to rant about the corruption of banks – a rant with which i agree wholeheartedly – but wish to blame the problem on ‘material self-interest’, quoting tony judt in support. i find this an odd logic. it’s a bit like noticing that lots of people with guns kill people, and then suggesting that the problem isn’t the guns, but the morality of the people who use them. well, perhaps that is what the national rifle association does, but it seems to many people (including the current president) that the world would be a lot safer if the guns weren’t around. furthermore, it’s much easier to intervene in matters like the availability of guns than it is to think about how we change the morality of citizens. like ‘changing the culture’, vague explanations add up to nothing more than windy rhetoric. to reiterate what seems to me obvious. all of your examples are big organizations. therefore, why don’t we look to their ‘bigness’ as an explanation. it’s a perfectly scientific procedure, which just involves isolating one variable, and then trying to see if that might be a symptom of some sort of problem. it is quite possible to argue for this in two ways. one is to suggest, as i did above, that the ultimate ‘cause’ doesn’t matter that much (bad apples, culture, distance from impact of decisions, market dominance or whatever) when we can see that the consequence of these ‘too big to fail’ organizations is so damaging for people, the environment, democracy, even the economy. in other words, whatever the reason, we can agree that big causes bad, so we should try to get rid of big. again, guns kill people, so let’s get rid of the guns. however, i also think that it’s quite possible to make the argument in different ways, and without being distracted by your general fluff about a decline in moral standards. for example, and as i suggested above, there seems to be some evidence that decision makers who are insulated from the effects of their decisions (by hierarchy or geography) are less likely to care much about the impacts on others. it’s what zygmunt bauman, in his splendid book on the holocaust, termed ‘adiaphorization’, the making of something irrelevant to a particular decision (bauman ). if i can’t see and smell the pollution, if i can’t hear the noise, if don’t know the people without jobs, or the people who have to do two jobs, or the suppliers who can’t cover their costs, then i am more likely to make decisions without regard for such ‘externalities’. so, the bigger the organization, the more effectively it functions as a structure which hides pain from the privileged inhabitants of the executive suite. from the dizzy heights of the corporate tower, you can’t hear the sounds of the street. might i persuade you to agree with me here? gordon: i agree up to a point! ‘out of sight, out of mind’ facilitates, but doesn’t inspire, big organisation executives to turn a blind eye to bad things that are being done by their organisations. take the example of martin winterkorn, vw’s ‘endlessly sorry’ boss, who retired in disgrace after us regulators had revealed that vw had used ‘defeat devices’ to cheat us emissions tests for its diesel cars. he had accused his company of betraying their customers’ trust. and, in a widely broadcast video, he had vowed to ‘fight on doing everything in his power to restore faith in germany’s proudest industrial brand’. he denied all knowledge of it himself, though plenty of vw people must have known about it. is it credible to imagine that he knew nothing about a widespread policy to evade emissions regulation in many countries? margaret heffernan ( ) provides many examples, in mostly large organisations, of what she refers to as ‘wilful blindness’. she describes in some detail the wilful blindness at bp ahead of the deepwater horizon oil spilll catastrophe. vw’s ‘defeat devices’ may be in the same category. bp and vw are both huge organisations. but the point heffernan makes is that the blindness is wilful. it’s the wilfulness that has to be rectified. winterkorn’s weak assertion that he didn’t know is, at the very least, a confession of ignoring something that he could easily have discovered. the real question is what gives rise to wilful blindness? the wilfulness is not the result of size, but is motivated by ‘bad theory’. that is to say, a set of assumptions about the co-incidence of self-interest and the effectiveness of markets which are dangerously common in economic policy circles and business schools. as sumantra ghoshal put it: ‘by propagating ideologically inspired amoral theories, business schools have actively freed their students from any sense of moral responsibility’ (ghoshal, : ). that freedom affects organisations of all sizes; it’s just that the big ones are more newsworthy. martin: i agree absolutely that ‘bad theory’ is taught in business schools, and they have their culpabilities here, but i’m not sure that you can blame them for vws attempt to wilfully subvert the attempts by legislators in many countries to improve air quality for their citizens. that’s rather like blaming primary schools for the moral failings of adults. there is a connection of course, because business schools (often) teach that the aim of commercial activity is profit, and the bigger you are, the more profit you make. there is a growth imperative built into such theories, and it’s one that suggests that vw (in ) was the best car manufacturer in the world because it was the biggest. the second best was toyota, close behind with a revenue of $ billion. this was the same company that lied about problems with the accelerator for one of their models, twice, and ended up having to pay $ . billion in fines in the us in . third in the list is general motors, which in was being investigated for claims that it knew about an ignition switch problem in which caused deaths but was not made public because it would have cost too much to fix it. again, we are led back to some connection between scale and certain sorts of short term profit and salary maximising behaviours. you wish to make this into a moral question, blaming the business schools for teaching a theory of selfishness, and then expressing disappointment about the activities of some managers in some organizations. i think that the way that you frame the problem doesn’t allow us to get to the bottom of it, which is that we now face a situation in which many markets are dominated by huge corporations. these companies have a collective interest in evading state regulation – i’m willing to bet that the vw story is the tip of the iceberg – and also in shaping the business environment in order to maximise shareholder value and executive pay. i think that scale seems to be at the bottom of all this, whether it results in the avoidance of responsibility or the exclusive focus on profit. so, in the spirit of plato, here’s my proposal. no commercial organization should be allowed to have more than employees. if they get bigger than that, they have to split into two. further, to ensure that we don’t just develop complex nests of off shore tax evading holding companies, no company is allowed to own another. we give corporations their license to operate, so let’s modify it a little, in the name of the common good. simple. what’s wrong with that? gordon: my point is that there is something much more sinister than simply size going on and that you are doggedly refusing to see that point. instead, i think that the vast majority of human beings are not innately criminal, but they are corruptible. we should be asking what is it that is responsible for such corruption? that being said, there is a lot of common ground here. it is certainly true that big bad organisations do more harm than small bad organisations. moreover, organisations that have developed monopolistic ability and expertise in fixing and abusing markets are invariably big as well as bad. similarly, organisations that have developed so that their failure might be thought likely to do huge damage, such as some banks, are also invariably big. and it is also true that some organisations are held to be too big to manage. so, for the sake of the debate, i’ll agree with you and plato. let’s limit organisations to employees. how do you propose to do that? martin: agreement breaks out, but yet i feel suspicious. let me have a go at some further specification then. first, i assume that we must be referring to one state. much as i would like to be able to set global restrictions, that seems unlikely without effective trans-national agreements and a global regulator. so, let just assume that we are discussing the uk, and that i have a mandate to pass two pieces of legislation. the first only allows employees to be on any company’s payroll. this does not include staff who are self-employed, though a problem for my plan could be staff who are employed by someone else – an agency for example – but who are working in a different organization. however, the agency could only have employees too, so it should even out in the end. a license to operate in the uk will depend on compliance with this law for any uk operations. the second piece of legislation will prevent one organization from owning a majority shareholding in any other, in order to ensure that companies can’t get round the first piece of legislation simply by owning other companies. again, this sounds simple, but will doubtless have to be refined in order to cope with all the many exceptions that will be manufactured by lawyers, probably involving overseas territories, shell companies, beneficiaries and so on. (all practices that are particularly common in the uk, as well as being extremely profitable for the city law firms that set them up.) now, there are still plenty of problems in this, most notably the way that the actual size of companies can be disguised through off-shore holdings which are beyond the reach of uk law. but then we shouldn’t be surprised that legislation in one state can’t solve the problems of global business. this is a clear problem in many areas – taxation, accounting, carbon offsetting and so on – and i don’t propose to be able to solve those problems here. however, what my new laws can do is to prevent mega-corporations from operating in the uk as mega-corporations, and in the area of financial services at least, this is not a trivial matter. there will be threats about companies pulling out of the uk, but most won’t. this is largely because they wouldn’t want to lose access to such a large market. the same applies to any reasonably big economy, so unless a company decides to refuse to sell its goods and services in a particular part of the world, it will have to comply with local legislation. corporations can make profits in particular countries because our governments allow them to. we give them a license to operate, but policy makers often act as if it is they are flighty creatures who must be tempted with treats. with so much evidence that big companies cause big problems, let’s take the initiative. governments already intervene in what companies do, whether in terms of tax, health and safety legislation, environmental standards and so on - so why not also size? from the sherman antitrust act in the usa onwards, there have been attempts to break up big organizations and this has sometimes been successful. for example, in , the rockefeller family’s standard oil was sued by the us justice department under federal antitrust law which eventually resulted in it being broken into separate companies. there is no reason why such legislation couldn’t be enacted in the uk, for companies which are headquartered in the uk. as senator john sherman put it in – ‘if we will not endure a king as a political power we should not endure a king over the production, transportation, and sale of any of the necessaries of life’ (reich ). gordon: assuming we are referring to one state rather than the whole world, and assuming you have a mandate to pass two pieces of legislation, makes you sound a bit like a neoclassical economist or business school professor, stating the implausible assumptions before specifying unworkable models. we should make only one assumption - that we are dealing with the real world as it is, and trying to make the best of it. i’m % with you regarding anti-trust legislation, but as usual you misunderstand the issue. it is anti-trust not anti-size. breaking up monopolists whether or not they can be shown to be operating against the common interest has got to be right. that was a lesson learned in the s following the wall street crash. uk legislation to protect competition existed right through to the s, together with the regulatory bodies to ensure it was actively applied. the office of fair trading (oft) could assess any merger and acquisition activity and if it looked like it was going to result in a market share of % or more they could refer it to the monopolies and mergers commission (mmc). that would automatically either completely stop the deal or at least delay completion for a year or more, removing any opportunistic deals resulting from the short term coincidence of share prices. the oft could also decide to review industries and markets if there was evidence of monopolistic practices which might be against the public interest, and then recommendations could be made to the mmc that could result in those engaged being broken up. the oft was divested of those powers during the s, after which it could only act on the basis of activities that could already be proved to be against the public interest. proof necessitates much detailed analysis, and hence resources, but the resourcing of the oft was reduced so that it was effectively made more or less powerless long before its remains were buried in the competition and markets authority (cma) in . so i do agree regarding anti-trust legislation, and i would like to see its operation properly funded and supported. furthermore, there is a track record of it being practically feasible and effective in the real world. making it apply around the world will certainly be more difficult in the globalised st century than it was in the s, but it’s not impossible. this is a challenge academics like you should find worth addressing! martin: agreed then. we like anti-trust legislation, but let me push this point further. you are right to say that there is no necessary relationship between size and monopoly, but it seems pretty obvious that there is a likely relationship. assuming a largeish market, then we can assume that the organization that would be big enough to monopolise it would also be big. so, once again, why not assume that scale (relative to size of market if you like) is a problem. why is that conclusion so unpalatable to you? the anthropologist robin dunbar has suggested that the optimum size of a social group, for both primates and humans, is around members. ‘dunbar’s number’, as it has since become called, has provoked considerable discussion since the early s, when it was originally proposed (see dunbar ). according to malcolm gladwell, the w l gore company decided only to open buildings that housed around employees. ( : passim). other studies have suggested relationships between brain size in primates and humans, and the size of the average social group or social network. dunbar and others have suggested that communication strategies are directly related to scale. now, even if we don’t accept some of the biological determinism implied by some of this research, it does seem common to sense to agree that there is, at least, a relationship between the size of a group and the quality of communication and interaction. now, isn’t very many, a lot less than plato’s . yet it does seem to me that the red thread in all of my arguments with you in this dialogue concerns scale. i agree with you that questions of regulation matter, that culture is an issue, that what business schools teach and what economists preach are important. but, setting all of these aside, it seems to me evident that all policy makers and academics who research and teach such matters should have a clear preference for small organizations, for states of affairs that maximise face to face interaction and meaningful senses of responsibility. this could well mean breaking up big organizations, but it most certainly means encouraging small ones, in the hope that an economy which is dominated by lots of small businesses (rather than a few very large ones) will be more equal, local and responsible. the rush to growth is increasingly recognised, in environmental and economic terms, as a pathology which we need to address if we are to find solutions to the global challenges which face us (gibson graham , ; d’alisa et al ; felber ). in which case, let’s not assume that organizations must grow to become successful! so, as we reach the end of our discussion, would you like to summarise your position, your dogged defence of big companies, despite all the harm that they so clearly do? gordon: indeed! let’s imagine we have set up a small craft chocolate manufactory whose prime strength is the secret recipe on which its main products are based. people love the product and want more. the growth achieved justifies investment in more efficient plant and pays for the investment in further development of technology and people. such was cadbury, established in a single shop in birmingham in , and growing to become the uks biggest maker of confectionary. limitation on size would destroy the motive to succeed, which is something very close to the magic of being human. thus i oppose the restriction of scale per se. you refer to w l gore, a wholly admirable private company co-owned by the gore family and the employees. based in newark, delaware, it has sales revenue of around $ . billion and employs more than , people in nearly facilities world-wide (pearson, ; ). now if you are arguing merely to limit the number of employees per plant, rather than the size of the corporation in common ownership, that is something different. the optimum size will be dependent on the activity and the technology, but the gore argument has a lot going for it. however, i think breaking up the predatory corporate leviathans, which do so much damage, simply on the grounds of their size, is extremely difficult both to justify on logical grounds and to accomplish in practice. but in the past such corporate monsters have been broken up by regulation (eg anti-trust) and energetic exercise of the law. at this point in time, especially in us and uk, those regulatory powers have either been demolished or are simply left in abeyance, because they do not accord with the dominant neoclassical economic belief system which the self-perpetuating industrial, financial, media, academic and political establishment live by and promote. but that’s a whole other story! the softer side is, i believe, also important. by that i mean the development of benign and effective corporate culture, as, for example, demonstrated by w.l. gore & associates. ‘there are no titles or conventional lines of command at gore, where the only way of becoming a leader is to attract followers – if a project can’t attract people to work on it, then it doesn’t get done’ (caulkin, ). corporate culture is important and can be very much dependent on what we teach in business schools and universities. though we’ve touched on it, that is also another story. the key issue is that your focus on scale runs the risk of ignoring beliefs and behaviours, as well as punishing those who grow because they are successful. small is not always beautiful. martin: a brazilian friend of mine told me about a man who made beer for his family, friends and village. it was so good that it won a competition, and that led to an approach from a big company to buy the recipe for lots of money and sell the beer across brazil. the beer-maker turned the offer down. he was happy making a little money by producing great beer in small amounts. the same could be true of cadbury, since a brand which is part of the gigantic mondelez corporation. (a company which, after accquisition, immediately closed one of the uk cadbury factories, despite giving assurances that it wouldn’t.) why should growth be synonymous with success? why can’t we imagine a world with lots of small chocolate makers, each providing jobs in its own region, and using materials made or grown in that region? in times in which we all face the threats of global warming, a defence of growth on the basis of monetary incentives for innovators is no defence at all. we started this dialogue with plato, with a long dead philosopher who understood the importance of dialogue, and was audacious enough to believe that the ideas that it generates can help design a better world. though we may differ about our versions of what this world should look like, i think we both believe that we can only get there if we clarify our differences and agreements in the way that we have here. but, i would remind you, and as any teacher knows, dialogue works best with small numbers of 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beautiful. london: vintage. silverman, d, ( ) the theory of organisations. london: heinemann. tett, g, ( ), ‘penalise the banks but use the money well’, financial times, th november. treanor j, ( ) ‘fines are fine, but putting bank bosses behind bars is still tricky’, the observer, th may. http://bookboon.com/en/the-real-business-of-real-business-ebook nuclear physics a ( ) – nuclear physics a first measurements of beauty quark production at √ s = tev with the cms experiment vincenzo chiochia on behalf of the cms collaboration universität zürich, physik-institut, winterthurerstr. , zürich, switzerland abstract this article summarizes the first measurements of inclusive beauty production cross section in proton-proton col- lisions at √ s = tev and central rapidities. the results are based on different techniques, such as the identification of semileptonic b-decays into muons and inclusive jet measurements with secondary vertex tagging. the measurements probe b-quark production in different regions of transverse momenta. the experimental results are compared with next-to-leading order qcd predictions and various monte carlo models. keywords: lhc, cms, beauty, bottom, secondary vertex, semileptonic decay . introduction it is important to understand inclusive b-quark production at lhc experiments for various reasons. firstly, in order to test qcd predictions which have been computed at next-to-leading order (nlo) precision but are still characterized by large scale dependence. secondly, because b-jets represent an important source of background for many of the most interesting physics searches, as the higgs boson and supersymmetric extensions of the standard model. most recent measurements performed at tevatron [ , , , ], hera [ , , , ] and lep [ ] are in reasonable agreement with qcd predictions in most regions of the phase space. two preliminary measurements of inclusive b-quark production at the center-of-mass energy of tev have been performed with the cms experiment [ ], based on different experimental techniques. the results are obtained with data collected in march-july . a first measurement is based on the identification of semileptonic decays of b quarks into muons and jets. muons from b- and c-quark decays can be distinguished using the transverse momentum relative to the jet, which is on average larger for b-events than in c-decays and for muons from light hadrons. this measurement probes the production process at low transverse momenta. a second measurement is based on the reconstruction of the secondary vertex in jets from the b-hadron decays, exploiting the high spatial resolution of the silicon pixel tracker. this measurement extends to large b-quark transverse momenta. both results are compared to nlo qcd predictions and various monte carlo (mc) models. . measurement techniques and results . . cross section measurement with semi-leptonic decays the measurement is based on the reconstruction of the muon from the semi-leptonic b-decay and associated jet [ ], using an integrated luminosity l = . nb− . at least one well-reconstructed muon with transverse momentum ar x iv : . v [ he p- ex ] n ov / nuclear physics a ( ) – pt,µ > gev and pseudorapidity |ηµ| < . is required. further cuts are applied on the longitudinal impact parameter, on the minimal number of hits associated to the track on on the quality of the track fit. tracks with pt > mev are clustered into track-jets with the anti-kt jet algorithm and r = . . the jet is defined as b-jet if it contains a muon satisfying the above requirements. after subtracting the muon momentum from the track-jet momentum, the track-jet energy is required to be et > gev in the plane transverse to the beam line. from the momenta of the selected muon ( ~pµ) and the associated track jet ( ~p j), the relative transverse momentum of the muon with respect to its track jet is calculated as prelt = |~pµ × ~p j|/|~pµ|. a fit to the observed p rel t spectrum, based on templates obtained from simulation (signal and part of the background) and data (the remaining background), is used to determine the fraction of signal events among all events passing the event selection. the templates used in the fitting algorithm are determined separately for the full sample and for each bin in muon transverse momentum and pseudorapidity. since the shape of the prelt distribution from charm decays and hadrons from light quarks or gluons cannot be distinguished by the fit, the two background components are combined. the inclusive b-quark production cross section, σb, is calculated from σb = nb/(�l), where nb is the number of events from b-decays extracted from the fit, � is the overall event selection efficiency and l the integrated luminosity. the result of the inclusive b-quark production cross section to muons, for the visible range pt,µ > gev and |ηµ| < . is σb = ( . ± . stat ± . syst ± . lumi) µb. single differential cross sections as function of the muon transverse momentum and pseudorapidity are obtained by determining nb and the efficiency in each bin (see fig. ). the systematic uncertainties ( %- %) are dominated by the description of the background from light quarks and gluons and modeling of the underlying event. at the present early stage of the cms experiment, the integrated luminosity recorded is known to about % precision. systematics [gev] t muon p +x ')[ nb /g ev ] µ ! b +x ! (p p t dp "d cms data = . gev) b mc@nlo (cteq m, m mc@nlo scale variation ( . - ) pythia (msel , cteq l ) cms preliminary = tevs - l= . nb !muon - - +x ') [n b] µ " b +x " (p p !d#d cms data = . gev) b mc@nlo (cteq m, m mc@nlo scale variation ( . - ) pythia (msel , cteq l ) cms preliminary = tevs - l= . nb (a) (b) figure : differential cross section (a) dσ d pµ⊥ (p p → b + x → µ + x�, |ηµ| < . ), and (b) dσ dηµ (p p → b + x → µ + x�, p µ ⊥ > gev). the points with error bars are the cms measure- ments. the horizontal bars indicate the bin width. the yellow band shows the quadratic sum of statistical and systematic errors. the systematic error ( %) of the luminosity measurement is not included. the dashed red lines illustrate the mc@nlo theoretical uncertainty as de- scribed in the text. the solid green line shows the pythia result. table : differential b-quark cross section dσ/d pµ⊥ for |ηµ| < . in bins of muon transverse momentum. the number of b-events (nb) determined by the fit, the efficiency (ε) of the online and offline event selection, and the differential cross section together with its relative statistical, systematic, and luminosity uncertainty are given. pµ⊥ n b ε dσ/d pt [nb/gev] stat sys lumi - gev ± . ± . % % % - gev ± . ± . % % % - gev ± . ± . % % % - gev ± . ± . % % % - gev ± . ± . % % % - gev ± . ± . % % % - gev ± . ± . . % % % - gev ± . ± . . % % % the muon trigger efficiency [ ] has been determined from data in minimum bias events. the statistical uncertainty on the trigger efficiency amounts to – %, depending on the muon trans- verse momentum and pseudorapidity, and is taken as a systematic uncertainty. the muon reconstruction efficiency is known to a precision of %. the tracking efficiency for hadrons is known with a precision of % [ ]. this induces a sys- tematic uncertainty of % on the number of events passing the event selection. the uncertainty in the tracking efficiency affects the b-fraction in the fit by about %. . . . / fo n ll (c en tra l) pt,μ (gev) | μ| < . fonll b->μ + b->c->μ powheg+herwig powheg+herwig psplt( )= . powheg+pythia cms data (c) figure : differential b cross section as function of the muon transverse momentum for |ηµ| < . (a) and pseudorapidity for pt,µ > gev (b), compared with pythia and mc@nlo predictions. the yellow band shows the quadratic sum of statistical and systematic errors (the uncertainty on the luminosity measurement is not included). the ratio of the measured cross section to the theoretical expectations from fonll and powheg are shown in (c). theoretical predictions for the cross section measurement were obtained with pythia . [ ], herwig . [ ], mc@nlo . [ ], fonll [ ] and powheg [ ]. the cteq l and cteq m parton densities [ ] were used for pythia and mc@nlo predictions, respectively. the pythia prediction for the visible b-quark cross section is σpythia = . µb, while mc@nlo gives [ . + . − . (scale) ± . (mb) ± . (pdf)] µb. the error for mc@nlo is obtained by changing the qcd renormalization and factorization scales independently from half to twice their default values. the pythia and mc@nlo predictions for the differential cross sections are shown in fig. (a)-(b). while pythia predictions are generally in agreement with the measurements, mc@nlo is below the measurement at low transverse momenta and central pseudorapidities. the herwig calculation with massive quarks agrees with the mc@nlo prediction within the theoretical uncertainties. the ratio of the measured differential cross section as function of pt,µ divided by the fonll and powheg predictions are shown in fig. (c). the powheg matrix element calculation is interfaced both to the pythia and herwig parton shower. the fonll calculation generally agrees with the data with the larger difference in the lowermost pt,µ bin. the powheg calculation with pythia parton shower is in agreement with fonll. the powheg prediction is below the data if interfaced with the herwig parton shower. / nuclear physics a ( ) – . . b-jet cross section measurement an additional measurement is performed, based on finding the decay vertex of b hadrons within jets [ ]. sec- ondary vertices with at least three associated tracks and hits in the silicon pixel detector provide a clean signal against backgrounds from light quark and gluon jets. the secondary vertices from b- and c-quark decays can be distinguished by their relative distance from the primary vertex using a d decay length significance, which is higher for b-jets than for c- and light flavor jets. the inclusive jet data is collected using a combination of minimum bias and single jet triggers. the jets with transverse momentum in the range < pt < gev and rapidity |y| < are reconstructed with the anti-kt algorithm [ ], with the jet clustering using a distance parameter r = . . particle flow objects [ , ] are utilized as input to the clustering algorithm, allowing for a reliable jet energy reconstruction and good energy resolution down to low transverse jet momenta. jets from b-decays are identified using a secondary vertex high-purity tagger [ ]. the secondary vertex is fitted with at least three charged particle tracks. a selection on the reconstructed d decay length significance is applied, corresponding to about . % efficiency to tag light flavor jets and % efficiency to identify b jets at pt = gev. the b identification efficiency with the selections used in theis analysis is between % and % at pt > gev and |y| < . the efficiency rises at higher pt as the b-hadron decay time increases in the laboratory frame, facilitating the identification of the decay vertex. the production cross section for b jets is calculated as a double differential dσ/(d pt dy) = nt fbc/(�jet�b∆pt ∆yl), where nt is the measured number of tagged jets per bin, ∆pt and ∆y are the bin widths in pt and y, fb is the fraction of tagged jets containing a b hadron, �b is the b tagging efficiency, �jet is the jet reconstruction efficiency and c is the unfolding correction. the integrated luminosity, l, is nb− . the �jet, �b and fb are all calculated from mc in bins of reconstructed pt and y. the b-tagged sample purity was also estimated from data, using template fits to the secondary vertex mass distribution, and the results were found to be in good agreement with mc expectations, well within the % statistical uncertainty. this constrains the charm mistag rate to within % of the mc expectation. the correction factor c unfolds the measured pt back to particle level using the ansatz method [ ]. the measured b-jet cross section is shown in fig. as function of the jet pt , in different rapidity bins. the leading systematic uncertainties at pt > gev are from the b-jet energy scale relative to inclusive jets ( %), from the data-driven constraints on b-tagging efficiency ( %) and from the mistag rate uncertainty for charm jets ( %) and for light flavor jets ( - %). conclusion factorization and renormalization scales were set to µf = µr = pt . the inclusive b-jet predic- tion is calculated with mc@nlo [ , ] using the cteq m pdf set and the nominal b-quark mass of . gev, giving a total b cross section of µb. the parton shower is modeled using herwig . [ ]. the results are compared to a nlo theory prediction (mc@nlo) and to the pythia mc (tune d t [ ]), and are found to be in good agreement with pythia and in reason- able agreement with mc@nlo. the nlo calculation is found to describe the overall fraction of b jets at pt > gev and |y| < . well, but with significant shape differences in pt and y. fitting the measured ratio of data to pythia in the phase space window < pt < gev and |y| < . to a constant, we obtain a global scale factor of . ± . (stat) ± . (syst), where the systematic uncertainty is a weighted average over all the bins contributing to the fit. the fit has χ /n df = . / . repeating the same fit for the ratio between reconstructed mc and generator-level mc results in a scale factor of . ± . with χ /n df = / , confirming good closure of the analysis chain. finally, the nlo/mc global scale factor is . ± . . the total b cross section of µb from the mc@nlo calculation has a sizable uncertainty from the choice of renormalization scale between µr = . and µr = (+ %, − %), from cteq pdf variations (+ %, − %), and from the choice of b-quark mass between . gev and . gev (+ %, − %). the dominant scale uncertainty is overlaid as an uncertainty band around the mc@nlo prediction in figs. (b) and . (gev) t b-jet p dy (p b/ g ev ) t /d p ! b- je t d - - )"|y| < . ( )" |y| < (# . )" |y| < . (# |y| < # . mc@nlo exp. uncertainty = tevs- cms preliminary, nb r= . pftanti-k (gev) t b-jet p dy (p b/ g ev ) t /d p ! b- je t d - - (gev) t b-jet p d at a / n lo th eo ry (gev) t b-jet p d at a / n lo th eo ry = tevs- cms preliminary, nb |y| < . |y| < ! . |y| < . ! |y| < ! . mc@nlo pythia exp. uncertainty (centered on ansatz) figure : measured b-jet cross section compared to the mc@nlo calculation, overlaid (left) and as a ratio (right). the pythia prediction is also shown, for comparison. conclusion we have measured the ratio of b-jet to inclusive jet production in pp collisions at √ s = tev center-of-mass energy for an integrated luminosity of nb− . we find an overall good agree- ment between data and pythia in the jet transverse momentum range < pt < gev and rapidity |y| < . , within about % statistical uncertainty and % systematic uncertainty. we also observe a reasonable agreement between the mc@nlo calculation and the measured overall b-jet fraction, within the % systematic uncertainty, but observe significant shape dif- ferences in pt and y. figure : left: differential b-jet cross section as function of the transverse momentum in different rapidity regions. right: ratio of the measured cross section to the nlo qcd prediction. the inclusive b-jet prediction is calculated with mc@nlo, using the cteq m pdf set and the b-quark mass of . gev. the results are compared to a nlo theory prediction (mc@nlo) and to the pythia mc, and are found to be in good agreement with pythia and in reasonable agreement with mc@nlo. the total b-quark cross section of µb from the mc@nlo calculation has a sizable uncertainty from the choice of renormalization scale between / nuclear physics a ( ) – . and (+ %,- %), from cteq pdf variations (+ %,- %), and from the choice of b-quark mass between . and . gev (+ %,- %). the dominant scale uncertainty is overlaid as an uncertainty band in fig. . . conclusions first measurements of b-quark inclusive cross sections were performed with the cms experiments in p-p collisions at √ s = tev. the measurements utilize different techniques and cover a wide range of b-quark transverse momenta. the results were compared to nlo qcd predictions and various monte carlo models. the cross section measured with semileptonic decays into muons is above nlo qcd predictions at low momenta and central pseudorapidities. the b-jet cross section measured with secondary vertex tagging for pt > gev is in reasonable agreement with nlo qcd but exhibits shape differences at large rapidities. it is foreseen to extend the measured kinematic range by analyzing the larger data samples collected in the lhc run. acknowledgements we thank m.cacciari and p.nason for the useful discussions and for providing the fonll and powheg predic- tions. references [ ] s.abachi et al. [d collaboration], phys. rev. lett. , ( ). [ ] b. abbott et al. [d collaboration], phys. lett. b , ( ). [ ] f. abe et al. [cdf collaboration], phys. rev. lett. , ( ). [ ] t. aaltonen et al. [cdf collaboration], phys. rev. d , ( ). [ ] c. adloff et al. [h collaboration], phys. lett. b , ( ). [ ] a. aktas et al. [h collaboration], eur. phys. j. c ( ). [ ] s. chekanov et al. [zeus collaboration], jhep ( ). [ ] s. chekanov et al. [zeus collaboration], eur. phys. j. c ( ). [ ] m. acciarri et al. [l collaboration], phys. lett b ( ). [ ] r. adolphi et al. [cms collaboration], jinst , s ( ). [ ] cms collaboration, cms-pas-bph- - ( ). [ ] t. sjostrand, s. mrenna and p. z. skands, jhep , ( ) [arxiv:hep-ph/ ]. [ ] g. corcella et al., arxiv:hep-ph/ . [ ] s. frixione, p. nason and b. r. webber, jhep , ( ) [arxiv:hep-ph/ ]. [ ] m. cacciari, s. frixione, m. l. mangano, p. nason and g. ridolfi, jhep , ( ) [arxiv:hep-ph/ ]. [ ] s. frixione, p. nason and c. oleari, jhep , ( ) [arxiv: . [hep-ph]]. [ ] j. pumplin, d. r. stump, j. huston, h. l. lai, p. m. nadolsky and w. k. tung, jhep , ( ) [arxiv:hep-ph/ ]. [ ] cms collaboration, cms-pas-btv- - ( ). [ ] m. cacciari, g. p. salam and g. soyez, jhep , ( ) [arxiv: . [hep-ph]]. [ ] cms collaboration, cms-pas-pft- - ( ). [ ] cms collaboration, cms-pas-pft- - ( ). [ ] cms collaboration, cms-pas-btv- - ( ). [ ] cms collaboration, cms-pas-qcd- - ( ). http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/ . introduction measurement techniques and results . cross section measurement with semi-leptonic decays . b-jet cross section measurement conclusions pii: s - ( ) - artificial intelligence ( ) – response g.w. flake, the computational beauty of nature gary william flake nec research institute, independence way, princeton, nj , usa as the author of the computational beauty of nature (hereafter, abbreviated as cbn) i am grateful for both the complimentary remarks as well as the thoughtful criticisms made by melanie moses, stephanie forrest, and martin berzins. as moses and forrest point out, cbn contains many of my intellectual biases and enthusiasms and, as a result, it undoubtedly contains imperfections related to my subjective view of science, mathematics, and philosophy. that said, i am delighted that the two reviews in this issue agree in positive aspects as much as they do. however, the two reviews do differ in some key aspects, which will be the focus of my response. i purposely designed cbn so that it could be read in multiple ways so as to suit the needs of different readers. as described in the preface, the first method of reading cbn would exploit the relatively self-contained and independent nature of the chapters, allowing the reader to skip around and pursue only those parts that look immediately appealing. a second method would use a more linear approach, working through the five parts in succession, so as to best appreciate the connections made between computation, fractals, chaos, complex systems, and adaptation. and still, a third reading would focus on the overall pattern that ties the five book parts into a single theme, as put forth in the preface, five “postscript” chapters, and the epilogue. as i wrote in cbn’s preface: if this book is a forest, then the first way of reading it is akin to poking at individual trees. the second way is analogous to observing how nearby trees relate to each other. the third way would equate to standing back and taking in the whole forest at once. it doesn’t really matter which path you take in exploring these ideas, as i expect that most readers will stick to one path in preference to the others. but if you happen to try all three paths, you may be rewarded with a special type of understanding that not only relates each topic to the others but also each topic as it is viewed from different perspectives. while berzins’s review samples cbn with a mixture of the first two reading methods, moses and forrest’s review examines all three methods while paying special attention to e-mail address: flake@research.nj.nec.com (g.w. flake). http://www.neci.nj.nec.com/homepages/flake/. - / /$ – see front matter  published by elsevier science b.v. pii: s - ( ) - g.w. flake / artificial intelligence ( ) – the third. taking a wider view, i am happy that different reviewers are evaluating cbn from a variety of positions and motivations. in the end, the mixture should give a more accurate description of the book, while also giving potential readers a better estimate of the value that they will yield from it. for more reviews of cbn (as well as java and c source code, the figures, glossary, and bibliography from cbn, and many other educational resources), please see http: //mitpress.mit.edu/flake/. aly Ð reflections on sleeping beauty reflections on sleeping beauty frank arntzenius . introduction adam elga ( ) presents a puzzle, the ‘sleeping beauty’ puzzle, which concerns the updating of belief when a person, sleeping beauty, finds some- thing out about her temporal location in the world. he claims that in such cases, even though she apparently only learned something about her tem- poral location in the world, and nothing about the world per se, she should nonetheless change her degrees of belief in what the world is like. and elga claims that in so doing she will violate bas van fraassen’s ‘reflection prin- ciple’. (see van fraassen and van fraassen .) after presenting elga’s argument i will present an alternative argument which has as its conclusion that sleeping beauty should not change her degrees of belief. i will then argue that neither of these arguments by itself is compelling, that one should distinguish degrees of belief from acceptable betting odds, and that some of the time sleeping beauty should not have analysis . , january , pp. – . © frank arntzenius frank arntzenius definite degrees of belief in certain propositions. finally i will argue that the sleeping beauty puzzle has to do with cognitive malfunction rather than with the updating of self-locating beliefs, but that nonetheless the updat- ing of self-locating beliefs is interestingly different from the updating of ordinary beliefs about the world. . sleeping beauty some researchers are going to put sleeping beauty, sb, to sleep on sunday night. during the two days that her sleep will last the researchers will wake her up either once, on monday morning, or twice, on monday morning and tuesday morning. they will toss a fair coin sunday night in order to determine whether she will be woken up once or twice: if it lands heads she will be woken up on monday only, if it lands tails she will be woken up on monday and tuesday. after each waking, she will be asked what her degree of belief is that the outcome of the coin toss is heads. after she has given her answer she will be given a drug that erases her memory of the waking up; indeed it resets her mental state to the state that it was in on sunday just before she was put to sleep. then she is put to sleep again. the ques- tion now is: when she wakes up what should her degree of belief be that the outcome was heads? answer : her degree of belief in heads should be / . it was a fair coin and she learned nothing relevant by waking up. answer : her degree of belief in heads should be / . if this experi- ment is repeated many times, approximately / of the awakenings will be heads-awakenings, i.e. awakenings that happen on trials in which the coin landed heads. . why sleeping beauty should change her mind elga argues that answer is the correct answer. his argument is as follows. when sb wakes up she is certain that she is in one of three predicaments: h : heads and it is monday t : tails and it is monday t : tails and it is tuesday let p represent the degrees of belief that sb should have when she awakens. suppose that when she wakes up she learns that the outcome is tails. by the symmetry of the situation she ought then to have degree of belief / that it is monday, and degree of belief / that it is tuesday. thus p(t / t or t ) = / . and hence p(t ) = p(t ). alternatively suppose that when she wakes up she learns that it is monday. it seems that then she still ought to have degree of belief / that the outcome was heads. in fact elga gives an apparently compelling argu- reflections on sleeping beauty ment for this conclusion, by considering a slightly different case. suppose that the coin is tossed on monday night rather than sunday night. if it comes up heads sb will not be woken up on tuesday, if it comes up tails she will be woken up on tuesday. whether the coin is tossed on sunday night or monday night ought to make no difference to her degrees of belief. but it is clear that if she learns that it is monday, and she knows that a fair coin is to be tossed on monday night, then she ought to have degree of belief / that it will come up heads. now, learning that it is monday amounts to learning that she is in h or t . thus p(h /h or t ) = / . and this entails that p(h ) = p(t ). altogether we therefore have p(h ) = p(t ) = p(t ) = / . the surprising consequence of this argument is that she started out on sunday with a degree of belief / in heads, and by merely waking up she has changed her mind: she has switched her degree of belief to / , despite the fact that she received no new information about the world. (here ‘no new information’ means: ‘no new non-self-locating information’.) this violates bas van fraassen’s ‘reflection principle’, which entails that if a person p is now certain that tomorrow p will have degree of belief x in r, while suffering no ‘cognitive mishaps’ between now and tomorrow, then p ought to now have degree of belief x in r. elga’s explanation of these sur- prising consequences is that in sleeping beauty type cases ‘you have gone from a situation in which you count your temporal location as irrelevant to the truth of h, to one in which you count your own temporal location as relevant to the truth of h.’ ( ). frankly speaking, this ‘explanation’ still leaves me puzzled. . why sleeping beauty should not change her mind i will now quickly argue that sleeping beauty should not change her mind, that is, that she should maintain degree of belief / in heads when she wakes up, and then spend some time defending this argument against objections. the argument is simple: sb gains no new information that is relevant to the outcome of the coin toss, she should not violate condition- alization and/or reflection, and hence her degree of belief upon waking up should be what it was on sunday, namely / . (for a more elaborate and explicit version of this argument see lewis .) a first worry about this argument is that if it is compelling, then elga’s argument had better be faulty. i will postpone discussion of that issue to the next section. a second worry is that in the long run / of sb’s awakenings will be tails- awakenings. thus, if she bets according to her degree of belief of / , she can be expected to lose money against a bookie, and she and the bookie know this in advance. i will argue that the resolution of this worry is that she should bet at odds that differ from her degrees of belief, and that this frank arntzenius is perfectly consistent with standard bayesian lore. i will argue for this by means of some examples. suppose that a bookie comes to you on sunday and allows you to bet at : odds on the toss of a fair coin on monday, where you can nominate which side you are betting on. here : odds means that you win $ if it lands on the side you nominate and you lose $ if it lands on the other side. clearly you should not accept. next, the bookie gives you a slightly different offer. he still offers you a bet at : odds. but now the absolute value of the bet depends on the outcome of the toss in the following way: if the toss lands heads the bet is $ versus $ , if the coin lands tails the bet is $ versus $ . now you should be indifferent as to whether you accept the offer, and if you do accept the offer you should nominate tails. for if you do that and it lands heads, then the bet is $ versus $ , so you loose $ , while if it lands tails the bet is $ versus $ and you win $ . so you loose $ or win $ , and each is equally likely. though this case does not seem as puzzling as the sleeping beauty case, there is something puzzling about it. if you accept the offer on sunday, then there is a % chance that you are committing yourself to bet a on monday, and there is a % chance that you are committing yourself to bet b on monday, where each of bets a and b are bad bets according to your degrees of belief. the puzzling thing is that this commitment is nonetheless not a bad commitment. this may seem less puzzling when you realize that this commitment can be re-described as a choice, made by you on sunday, to accept bet # of the following two bets that you are offered: bet# : you bet on tails: you win $ , or loose $ bet# : you bet on heads: you win $ , or loose $ . nonetheless it remains the case that if you accept the offer on sunday you are committing yourself to one of two possible bets on monday, each of which is bad according to your degrees of belief. the next example is the sleeping beauty example, except that each time that sb is woken up she is not asked for her degrees of belief in tails, instead she is asked whether she is willing to accept a bet at : odds on tails. sb should be indifferent, since the structure of this case is exactly the same as the case above. in the variable stakes bet, by direct stipulation, the poten- tial gains and losses are multiplied by when it is tails; in the sleeping beauty case the potential gains and losses are multiplied by when it is tails because sb is twice asked the same question, and is bound to give the same in email exchanges i have learned that jamie dreyer has invented essentially the same example (his ‘variable stakes casino example’) before i did. reflections on sleeping beauty answers. this suggests that sb’s degrees of belief in heads upon waking up should remain unchanged at / , but that nonetheless upon waking up she should accept any bets on tails at odds of : or better. one might still be worried: doesn’t betting at odds that are bad according to one’s degrees of belief violate standard decision theory? let me give yet another example to explain why it needn’t. let us make three changes to the sleeping beauty case. in the first place let us assume that sb is offered a bet on tails at : odds (rather than : odds) each time she wakes up. secondly, there is another person, dormant belle, db, who is placed in exactly the same situation as sb is: she is offered the very same bets (on the very same coin toss) that sb is offered, and her memory will be erased after she accepts or declines a bet etc. thirdly, the payoff structure is altered. sb gets the gains or losses of her first bet, and of db’s last bet, if there is one. db gets the gains or losses of her first bet, and the gains or losses of sb’s last bet, if there is one. db and sb don’t know each other, but they each know that there is another person in the same situation as they are, and they each know what the payoff structure is. each is supposed to care only about the profits or losses that they themselves make. what should sb (and db) do? the answer is that sb upon waking should not accept a bet offered at : . the profits or losses that sb makes on db’s last bet, if there is one, are independent of sb’s choice whether to accept a : bet when sb wakes up. so sb needs only to decide for or against the acceptability of a single bet (on monday). she either gains $ or loses $ on that bet, depending on the outcome of a toss of a fair coin. so she should not accept the bet. db, if she is sensible, will reason the same way. it is a prisoners’ dilemma. let us next change the example a little bit. suppose that db is sb’s iden- tical twin sister and that both believe that whatever the one decides, the other will decide the same. should each accept the bet? well, that depends on what they regard as the correct decision theory. on a simple-minded version of evidential decision theory they ought both to accept the bet, since if both accept the bet, each either wins $ or loses $ , and each is equally likely. on the other hand, according to causal decision theory they should not accept. for holding fixed what the other does, no matter what the other does, each should expect to do better (by $ . per trial in the long run) by not accepting. now let us return to the standard sleeping beauty case. let us start by supposing that sb is an evidential decision theorist, and that sb accepts that her agreeing to a particular bet on one particular awakening is good evi- dence that she will agree to it upon the other awakening, if there is one. thus, her acceptance of a bet on a particular awakening has two beneficial consequences if in fact the coin lands tails: she will win that particular bet, and she will make that bet again and win it again, upon her other awak- frank arntzenius ening. so if sb accepts evidential decision theory she should accept a bet on tails at : odds, even though her degree of belief in tails is / . in contrast let us suppose that sb is a causal decision theorist. clearly sb’s acceptance of a bet on tuesday does not cause her acceptance of that bet on monday. moreover it is implausible to claim that her acceptance of a bet on monday causes her to accept that bet on tuesday, since it is more plausible to claim that both acceptances have a common cause, namely sb’s mental state on sunday. so let us suppose that sb does not believe that her acceptance of a bet any one day causes her acceptance of such a bet on the other day. let us furthermore suppose that sb accepts a rather strict version of causal decision theory, namely one according to which a ‘dependency hypothesis’ (see lewis ) consist of a listing of the causal effects of sb’s possible actions. given sb’s acceptance of such a causal decision theory, and given her belief that acceptance of a bet on any one day does not cause her acceptance on any other day, she should, upon waking up, not accept a bet at odds that differ from her degrees of belief. as a final example, let us suppose that sb believes that any acceptance of any bet on any one day is counterfactually connected to such an accep- tance on the other day, i.e. let us suppose that sb accepts the claim ‘if i were to accept this bet now, then i would accept it upon any other such waking’. and suppose that sb accepts ‘counterfactual decision theory’, i.e. a causal decision theory according to which counterfactual dependencies are the relevant dependencies. then sb will accept bets at odds that differ from her degrees of belief, e.g. a bet on tails at odds : even though her degree of belief in tails is / . so, one can hold on to van fraassen’s reflection principle, and to bayesian updating by conditionalization, as long as one does not adhere to a strict version of causal decision theory. does this mean that we have an argument from the premiss of ‘van fraassen reflection’, or from the premiss of ‘bayesian conditionalization’, to the conclusion that strict causal decision theory is false? that would be surprising! or should one instead conclude that causal decision theory is correct, that sb’s degree of belief in heads should be / , but that sleeping beauty is one of those strange cases where a causal decision theorist is punished for her rationality, and pre- dictably so? that would be interesting! but before jumping to conclusions, let us take a step back. . why sleeping beauty may, or may not, change her mind if the coin lands tails on monday night sb’s degrees of belief will be reset to what they were on sunday night. thus, if the coin lands tails, then sb, from a bayesian point of view, will have a cognitive malfunction: she will violate conditionalization. since she knows this in advance (and all the reflections on sleeping beauty time) the obvious question is: what should she do to avoid ‘damage’ as much as she can? before discussing what the best damage control strategy is for sb, let me, in the light of the noted cognitive malfunction, explain what is wrong with the views expressed in the previous two sections. what is wrong with elga’s argument that sb should change her mind upon waking up? well, elga’s argument assumes that if sb were to learn that it is monday she should arrive at her new degrees of belief by condi- tionalizing the degrees of belief she has when she wakes up. and it assumes that, were she to learn that it is tails, she should arrive at her new degrees of belief by conditionalization from the degrees of belief she has when she wakes up. this argument would be fine if indeed sb could be a good bayesian throughout. but the conclusion of elga’s argument is that sb should not be a good bayesian, since she should violate reflection, and should violate conditionalization on the transition from sunday evening to monday morning after wake-up. moreover, it is inevitable that, if the coin lands tails, then on the transition from monday to tuesday sb will violate conditionalization, since her degrees of belief will be artificially reset. what’s more, if sb follows elga’s advice for her degrees of belief and she happens to be an evidential decision theorist she can expect to loose money. so elga’s argument is not compelling. what is wrong with my argument that sb should not change her mind upon waking up? in essence, it has the same problems as elga’s argument. i argued that sb should not change her mind, by assuming the validity of van fraassen’s reflection principle, and by assuming that her degrees of belief upon waking up come from her degrees of belief on sunday by conditionalization. since there is nothing (relevant) to conditionalize upon when she wakes up, her non-self-locational degrees of belief must remain the same upon waking up. this would be a fine argument if sb could always update by conditionalization. but she can’t. moreover if she accepts my argument and happens to be a strict causal decision theorist, she can expect to lose money. so my argument is not compelling. so let us look afresh at the question as to what sb should do. as should be obvious, there are several options. for instance, even while admitting that elga’s argument and my argument for the above two views are incon- clusive, sb could still decide to adopt one or the other of those degrees of belief on different grounds. but let me also mention some other options, before lurching towards resolution. when she wakes up she could do exactly what she would do on monday morning if she had no worries about cognitive malfunctions, namely update her location belief to ‘it is now monday’, and leave her degrees of belief in heads the same. if she does this she will have no cognitive damage on monday: on monday morning she will have exactly the beliefs that a person p would have who does not have to worry about possible cognitive frank arntzenius malfunction. note that this procedure is not the same procedure as advo- cated in the previous section. for on the view advocated in the previous section sb should not have degree of belief in ‘it is monday’ upon waking up, while on the view currently under consideration she should. the current view has the advantage that sb suffers no cognitive damage what- soever on monday. but then, of course, on a tuesday morning wake-up, if there is one, she would have severe cognitive damage: she would have the very same degrees of belief as she had on monday, and those are not the degrees of belief that a person who functions cognitively perfectly through- out, would have on a tuesday wake-up. one can think of many such schemes, and each will include some cognitive damage as compared to a perfectly functioning individual. so let us look more closely at the issue of damage control in order to get some grip on a preferred scheme. on sunday sleeping beauty can contemplate all the bets that she might be offered on future days. suppose that she is forced to accept bets when she wakes up, for example, because a gun is pointed at her head, and she is told that she has to state the odds at which she is indifferent as to which side of the bet she takes. now suppose that these bets are offered by a bookie who adjusts the offered bets according to the outcome of the toss, which he knows. then, of course, the bookie can make sb lose money, and there is no relevant damage control possible. but suppose this is done by a bookie who does not adjust the offered bets to the outcomes. then, given sb’s degrees of belief on sunday, she ought to be able to figure out what the best strategy should be with respect to such possible future bets. now, let us ensure that sb does not learn anything about which day it is from the bet that she is offered, by assuming that sb is certain that what- ever bet she is offered she will be offered the same bet on monday as on tuesday. then it should be clear which bets sb should accept upon waking up. for she knows that in the long run, if the situation were repeated, there will be / heads-awakenings, and / tails-awakenings. since she will always accept or reject the same bets, she has good reason to accept only bets on tails at : odds (gain if it is tails, lose if it is heads), or better. so she knows what bets to accept upon waking up. what about her degrees of belief upon waking up though? well, we have seen above that if sb has degree of belief / in heads, and accepts strict causal decision theory, she will indeed accept bets on tails at : odds or better. but we have also seen that if sb has degree of belief / in heads, and she accepts strict evidential decision theory, then she will also accept bets on tails at : odds or better. and there are some other possible combinations that will have her accept bets on tails at : odds or better. one possible sug- gestion therefore is that sb should, upon waking up, simply set her degrees of belief to whatever they need to be, given the decision theory and depen- reflections on sleeping beauty dencies that she accepts, in order for her to find acceptable bets on tails at : odds or better. however, it seems rather odd that sb’s degrees of belief would depend on the decision theory that she accepts. surely if she changes her mind about which decision theory is correct she should not thereby be forced to change her epistemic state with respect to heads. surely changing her mind about decision theory does not entail changing her mind as to what the world is like with respect to outcomes of coin tosses. thus it seems more plausible to say that her epistemic state upon waking up should not include a definite degree of belief in heads. she should of course know which bets she should accept and which ones she should not, but her epistemic state does not include a natural candidate for a context-independent degree of belief in heads. in fact her epistemic state upon waking up is best described by saying that she believes that she is in the situation described in the sleep- ing beauty story. not to have a definite degree of belief in heads might be strange, but it might be the best that she can do given the forced irra- tionality that is inflicted upon her. finally, as should be clear by now, on my view self-locating learning plays no relevant role in the sleeping beauty case. the real issue is how one deals with known, unavoidable, cognitive malfunction. but i still think that there is something interesting and new about self-locating learning. for instance, suppose that one knows exactly what the world is like and exactly where one is in the world. then let some time lapse. if one is not looking at a clock, one will typically no longer be certain what time it is, and hence where one is in the world, and one would not normally call this a cogni- tive malfunction. nonetheless, this change in one’s cognitive state is not due to conditionalization. moreover, it includes a transition from total cer- tainty to uncertainty. that is a new form of cognitive change incompatible with conditionalization, which is not really ‘learning’, but nonetheless in a rather literal sense consists of ‘updating’. this means that standard bayesian lore, after all, does have to be modified in order to deal with self- locating beliefs. however, that is not the main moral of the sleeping beauty story. the main moral of that story is that in the face of forced irrational changes in one’s degrees of belief one might do best simply to jettison them altogether. rutgers university new brunswick, nj - , usa arntzeni@rci.rutgers.edu many thanks to adam elga, brad monton, ned hall, jamie dreyer and bas van fraassen for some useful email exchanges on the sleeping beauty puzzle. e. j. lowe references elga, a. . self-locating belief and the sleeping beauty problem. analysis : – . lewis, d. . causal decision theory. australasian journal of philosophy : – . lewis, d. . sleeping beauty: reply to elga. analysis : – . van fraassen, b. . belief and the will. journal of philosophy : – . van fraassen, b. . belief and the problem of ulysses and the sirens. philosophical studies : – . analysis . , january , pp. – . © e. j. lowe neural correlates of beauty hideaki kawabata and semir zeki wellcome department of imaging neuroscience, university college, london wc e bt, united kingdom submitted july ; accepted in final form november kawabata, hideaki and semir zeki. neural correlates of beauty. j neurophysiol : – , ; . /jn. . . we have used the technique of functional mri to address the question of whether there are brain areas that are specifically engaged when subjects view paintings that they consider to be beautiful, regardless of the category of painting (that is whether it is a portrait, a landscape, a still life, or an abstract composition). prior to scanning, each subject viewed a large number of paintings and classified them into beautiful, neutral, or ugly. they then viewed the same paintings in the scanner. the results show that the perception of different categories of paint- ings are associated with distinct and specialized visual areas of the brain, that the orbito-frontal cortex is differentially engaged during the perception of beautiful and ugly stimuli, regardless of the category of painting, and that the perception of stimuli as beautiful or ugly mobilizes the motor cortex differentially. i n t r o d u c t i o n the search for the source of beauty, of whether it resides in the object apprehended or in the perceiving subject, has exer- cised the speculation of philosophers and writers throughout the ages. plato, whose writings dominated esthetic theories and discourse for much of the last , years, believed that beauty has an existence of its own that is independent of the subject apprehending it. even for him, however, participation by the individual was critical. his lofty discourses in phaedrus and the symposium, which emphasize beauty as something with an eternal presence outside the individual, are nevertheless coun- terbalanced by the concession in hippias major that the beau- tiful is that which “is pleasing to the eye and ear,” that is, by participation. it is with the publication of kant’s work, and especially the critique of esthetic judgment, that the emphasis shifted more to a search for the principles of beauty and esthetic value in the perceiver. kant perspicaciously asked questions that lend themselves to experimental investigation: what are the conditions implied by the existence of the phe- nomenon of beauty and what are the presuppositions that give validity to our esthetic judgments? this work is an attempt to address the kantian question experimentally by inquiring into whether there are specific neural conditions implied by the phenomenon of beauty and whether these are enabled by one or more brain structures. the question that we address here is thus at a very basic level. we have not trespassed into more difficult terrain, to address questions such as the difference between the sublime and the beautiful that so exercised the thinking of those who wrote about beauty, among them winckelmann ( ), burke ( ), and kant ( ). nor have we addressed the important question of how what an individual regards as beautiful is conditioned by culture, upbringing, and inclination. while acknowledging these important issues, we have tried to circumvent them by allowing subjects to determine themselves what is beautiful and what is not. our question thus became the simple one of using paintings to ask whether, regardless of how different subjects perceive them, there are brain areas that are consistently active across subjects when they perceive a paint- ing as being beautiful and, conversely, whether there are brain areas that are specifically active when they view paintings that they consider to be ugly. while many imaging studies have shown the association of specific functions with distinct parts of the brain, such an association is not a priori obvious in the field of esthetics. beauty and ugliness constitute polar extremes of a continuum. instead, therefore, of finding distinct cerebral areas whose activities correlate with the experience of beauty or of ugliness, respectively, it seemed to us equally likely that we would find one or more areas in which the intensity of activity reflects linearly the degree of beauty bestowed on an object by the viewer. m e t h o d s subjects ten healthy, right-handed subjects ( females) in the - to -yr age range participated in the study. they were all fully educated undergraduate or graduate students, and they had no special experi- ence in painting or art theory. all had normal or corrected-to-normal vision, and none had a history of neurological or psychiatric disorder. informed consent was obtained from all and the study was approved by the ethics committee of the national hospital for neurology and neurosurgery, london, uk. psychophysical testing and scaling in psychophysical experiments prior to imaging, each subject viewed paintings for each painting category that were reproduc- tions viewed on a computer monitor. each painting was given a score, on a scale from to . scores of – were classified as “ugly,” – “neutral,” and – “beautiful.” each subject thus arrived at an independent assessment of beautiful, ugly, and neutral paintings. paintings classified as beautiful by some were classified as ugly by others and vice versa with the consequence that any individual paint- ing did not necessarily belong in the same category for different subjects. based on these psychophysical tests, a total of stimuli in each category (abstract, still life, landscape, or portrait) were viewed by subjects in the scanner, making a total of paintings viewed by each subject (because each category had paintings that had been classified as beautiful, neutral, or ugly) in random order of blocks in the scanner. however, in the ugly and beautiful categories, only paintings classified as – and – , respectively, were viewed in the address reprint requests and other correspondence to: s. zeki (e-mail: zeki.pa@ucl.ac.uk). the costs of publication of this article were defrayed in part by the payment of page charges. the article must therefore be hereby marked ‘‘advertisement’’ in accordance with u.s.c. section solely to indicate this fact. j neurophysiol : – , ; . /jn. . . - / $ . copyright © the american physiological societywww.jn.org scanner, whereas for paintings classified as neutral, paintings belong- ing to both categories and were viewed. functional mri (fmri) stimulus subjects were scanned between and days after the psychophys- ical determination described above. the stimuli were back-projected onto a screen viewed through an angled mirror. the resolution of the screen was , � pixels, and the height of each stimulus was . ° ( pixels), whereas the width varied. this was an event- related study, in which the rating (e.g., beautiful, ugly, or neutral) was unpredictable to maintain subjects’ attention. subjects were presented with blocks in random order, each block belonging to a different category of painting (e.g., landscape or portrait). each block contained eight paintings: of these, six belonged to one judgmental category and two to the other two categories. for example, a block contained eight paintings of which six had been classified as beautiful, one as ugly, and one as neutral. the stimuli in each block were presented in random order. each epoch (block) lasted s, and each painting was shown for s (no fixation required) with an interstimulus interval of � ms, during which the subject fixated a central cross. each of the paintings was presented twice but not in the same or in subsequent epochs, making a total of presentations. subjects were required to press one of three buttons in the scanner for each painting to indicate whether it was beautiful, ugly, or neutral. fmri data acquisition and analysis the techniques for data acquisition and analysis have been de- scribed before (zeki et al. ). scanning was done in a t mag- netom vision fmri scanner with a head-volume coil (siemens, er- langen, germany). a gradient echo planar-imaging (epi) sequence was selected to maximize the blood oxygen level-dependent (bold) contrast (te, ms; tr, . s). each functional image volume of the whole brain was acquired in slices, each consisting of � pixels, -mm thickness, with -mm gaps between slices. statistical analysis was done with spm (wellcome department of imaging neuroscience, london, uk). the epi images were realigned spa- tially, normalized to the montreal neurological institute template provided in spm , smoothed spatially with a -mm gaussian kernel, and filtered temporally with a band-pass filter with a low- frequency cutoff period of s and a high-frequency cutoff shaped to the spectral characteristics of the canonical hemodynamic response function within spm . the images were also realigned in time by using sinc interpolation before spatial normalization. data from all subjects were analyzed and combined in a fixed-effects analysis. all of the event types were segregated post hoc into a � event-related design. the two factors were the different response conditions (beau- tiful, neutral, and ugly) and the four different painting categories (abstract, landscape, still life, and portrait). the statistical maps were thresholded at p � . , corrected for multiple comparisons with an extent threshold of voxels. in the scanning session, all subjects viewed all the pictures and classified them into beautiful, neutral, or ugly by pressing a button. there was no significant difference in reaction time to the different stimuli (fig. ), most of which were classified as neutral. r e s u l t s figure shows that, reflecting the functional specialization of the visual brain (livingstone and hubel ; zeki ; zeki et al. ), viewing different categories of painting produces activity at different sites within it. this is especially so for faces and landscapes and is regardless of whether the paintings are classified as beautiful or not. we wanted to search for brain areas that responded specif- ically to one category of painting (e.g., portrait) over the others. such areas can be revealed using a cognitive conjunction approach (ca) (price and friston ) in which only voxels that show a significant and consistent increase in activity for one class of painting over any of the others are included. the contrast portraits versus non-portraits (a) produced activity unilaterally in the middle of the fusiform gyrus (fusiform face area (ffa) with talairach coordinates, , � , � ; ke � ; p � . , corrected), implicated in the recognition of faces (kanwisher et al. ) and bilaterally in the amygdala (left, � , � , � ; ke � ; p � . corrected; right, , � , � ; ke � ; p � . corrected), which is also implicated in facial perception (breiter et al. ; dolan et al. ); the ca of landscapes versus non-landscapes (b) pro- duced activity in the anterior part of the lingual gyrus ( , � , � ; ke � ; p � . , corrected), in the para-hippocampal place area (ppa) (epstein and kanwisher ), extending anteriorly into the hippocampal gyrus, and in area of the parietal cortex of the right hemisphere ( , � , ; ke � ; p � . , corrected); the activity produced by the ca of still life versus non-still life (c) was restricted to the lateral and middle occipital gyri, especially centered on left v (� , � , ; ke � ; p � . , corrected), but including areas v and v , and extending anteriorly into the posterior lingual gyrus; and at the corrected level, no activity was produced by the ca of abstract versus non-abstract (d). this probably reflects the fact that abstract paintings include the same featural and compositional elements that comprise the other paintings but have no additional unique properties, thus canceling out in the subtractions. fig. . behavioral data collected in the functional mri (fmri) study. a: the proportion of pictures that subjects responded to as beautiful, neutral, or ugly for the picture categories—abstract (a), still life (s), portrait (p), or landscape (l). the proportion for neutral was more than that for beautiful and ugly. b: averaged response times by condition and response type. there was no significant difference between categories and between responses in a -way anova ( category � response type), but the response time for neutral was slower than for other response types. neural correlates of beauty j neurophysiol • vol • april • www.jn.org we next charted, in a fixed effects analysis, areas whose activity correlates with viewing beautiful or ugly paintings regardless of category (fig. ). a contrast of beautiful versus ugly produced activity in the medial orbito-frontal cortex alone (� , , � ; ke � ; p � . , corrected). a contrast of beautiful versus neutral for all categories produced activity in the orbito-frontal cortex corresponding to ba (- , , � ; ke � ; p � . , corrected), and also in the anterior cingulate gyrus, corresponding to ba (� , , ; ke � ; p � . , corrected) and left parietal cortex (ba ; � , � , ; ke � ; p � . corrected). a comparison of ugly versus beautiful produced activity in the motor cortex bilaterally (left, � , � , ; ke � ; p � . cor- rected; right, , � , ; ke � , p � . corrected), whereas the contrast ugly versus neutral produced no activity. thus the areas that are involved in these contrasts are the medial orbito-frontal cortex, the anterior cingulate, the parietal cortex, and the motor cortex. the activity in motor cortex was more pronounced on the left, possibly reflecting the fact that all our subjects were right-handed. because the reaction times to beautiful and ugly paintings were the same, the activation of motor cortex is unlikely to be due to differences in reaction times to the two categories (see fig. ). with neutral stimuli acting as a baseline, we were able to chart the strength of activity in these areas as a function of the category of the stimulus. because the activities in the anterior cingulate and in the parietal cortex only became manifest in the contrast beautiful versus neutral, of greatest interest for our purposes is the activity in the orbito-frontal cortex and the motor cortex. parameter estimates are shown for all four areas in fig. , in which it can be seen that there is a linear relationship in activity in the orbito-frontal cortex and in the motor cortex, with beautiful pictures producing the highest activity in the former and ugly ones the highest in the latter. no such linear relationship was observed for activity in the ante- rior cingulate and left parietal cortex. thus the same areas are involved when stimuli that are considered beautiful or ugly are viewed, but activity in each reflects the judgmental category. the parameter estimates for each subject in the contrast beau- tiful versus (neutral � ugly) and the contrast ugly versus (beautiful � neutral) are shown in fig. . in fig. , we give the averaged bold signal changes for each painting category in the medial orbito-frontal cortex and the left motor cortex. regardless of the category of painting, the activities show consistent linear relationships in that there is a relative linear fig. . statistical parametric maps rendered onto a “standard brain,” showing category-specific activity as assessed by conjunction analysis, in the comparisons of portrait vs. non-portrait (a), landscape vs. non-landscape (b), still life vs. non-still life (c), and abstract vs. non-abstract (d), taken across response categories (corrected, p � . ). although abstract paintings produced no activity in the ca-corrected significance level, still life produced the greatest change at v (talairach coordinates, � , � , ), portraits in the middle fusiform gyrus (fusiform face area, ffa; , � , � ), and landscapes at the para-hippocampal place area (ppa; , � , � ). e–g: averaged parameter estimates for the three different painting categories for portrait (e), landscape (f), and still life (g) with the superimposed slice of the hottest voxel taken though a template brain. each red bar shows se of each relative condition. fig. . statistical parametric maps rendered onto a standard brain showing judgment-specific activity in comparisons of beautiful vs. ugly (a), beautiful vs. neutral (b), ugly vs. beautiful (c), and ugly vs. neutral (d) taken across painting categories (corrected, p � . ). a: the activity in the medial orbito- frontal cortex only (talairach coordinates � , , � ). b: the activities in medial orbito-frontal cortex (� , , � ), anterior cingulate gyrus (� , , ) and left parietal cortex (� , � , ). c: somato-motor cortex bilaterally (left � , � , ; right , � , ). d: no activity at corrected significant level. h. kawabata and s. zeki j neurophysiol • vol • april • www.jn.org increase of activity during the viewing of beautiful stimuli, and a decrease with ugly stimuli, even for abstract paintings. the association of each of the first three category of paint- ings, regardless of esthetic judgment, with activity in a specific part of the visual brain naturally raised the question of whether it is additional activity in these specialized areas that leads to a painting in the corresponding category being perceived as beautiful or whether other areas are engaged as well. using portraits and landscapes, which gave the most robust activity in two separate areas corresponding to regions implicated in the perception of faces and of places respectively, we conducted a psychophysiological interaction analysis (friston et al. ) between the medial orbito-frontal cortex and the hottest voxels in the two areas, in a fixed effect analysis. the results, given in fig. , show that there is no consistent relationship in the activity produced by beautiful, neutral, or ugly paintings in the two areas. this implies that it is not extra activity within a center that is specialized for a particular type of stimulus that correlates with whether it is ugly or beautiful. d i s c u s s i o n to the simple question of whether there are any specific brain areas that are engaged when subjects perceive something as beautiful, we obtained answers that are partly predictable and partly not. predictably, sight of a painting that is to be classified as beautiful or not engages, not the entire visual brain, but only the area(s) that is specialized for the processing and perception of that category of stimulus (moutoussis and zeki ). implicit in this demonstration therefore is that a functional specialization lies at the basis of esthetic judgments (zeki ). by this we mean that to be judged as beautiful or not, the picture must be processed by the area specialized for processing that category of work. predictably too, and in ac- cordance with the mass of imaging data showing the associa- tion of specific feelings and emotional states with specific brain structures, the judgment of a painting as beautiful or not correlates with specific brain structures, principally the orbito- frontal cortex, known to be engaged during the perception of rewarding stimuli (aharon et al. ; francis et al. ; rolls ; small et al. ) and, perhaps surprisingly, the motor cortex. less predictably, the results also tell us that there is no separate structure that is specifically engaged when stim- uli are perceived as ugly. parameter estimates show that it is rather a change in relative activity in the orbito-frontal cortex that correlates with the judgment of beauty and of ugliness. much the same pattern, though in reverse order, is character- istic of the motor cortex, where stimuli judged to be ugly produced the greatest activity and the beautiful ones the least, although both lead to a change from baseline activity. that the judgmental categories of beautiful and of ugly should not engage separate areas but relative changes of activity in the same areas is supported by previous electrophysiological evi- dence. kawasaki et al. ( ) have shown that single neurons in human orbito-frontal cortex increase their responses more to aversive than to pleasant stimuli compared with the neutral state, although they do not give reverse examples. another fig. . averaged parameter estimates for all response categories at medial orbito-frontal cortex (a; talairach coordinates, � , , � ), left motor cortex (b; � , , � ), anterior cingulate (c; � , � , ), and left parietal cortex (d; � , � , ). the medial orbito-frontal cortex and the motor cortex show a significant linear modulation of their response with esthetic judgment (f test, corrected, p � . ), whereas the anterior cingulated and the parietal cortex show no liner modulation. each red bar shows se of each condition. fig. . brain activities in motor cortex and in orbito-frontal cortex in individual subjects. a and b: glass-brain presentations of group results pro- duced in comparisons of ugly vs. neutral plus beautiful (a) and beautiful vs. ugly plus neutral (b). c and d: averaged-parameter estimates for subjects at the hottest voxel of the somato-motor and the orbito-frontal produced the activities by contrast of b and a. c: consistently higher bold responses for beautiful compared with non-beautiful judgments. d: of subjects had significantly more activity for ugly compared with non-ugly judgments in their motor cortex. each bar shows se of each condition. neural correlates of beauty j neurophysiol • vol • april • www.jn.org example of a direct relationship between cell response and reward expectation has been documented for anterior cingulate cortex in the monkey (shidara and richmond ). if one were able to obtain a good quantification of response vigor, one might be able to study the relationship between neural activity and esthetic judgment (as a function of reward) in a more quantitative way. it is hard to imagine, from these results, the possibility that stimuli judged to be beautiful or ugly engage different types of cell because one would then have expected equivalent responses in orbito-frontal cortex, not relative in- creases or decreases. we do not suggest that any of the areas described here act in isolation. not only do the results suggest a reciprocal interac- tion between motor and orbito-frontal cortex, but the wide- spread cortical connections that each of these areas has with other cortical regions makes it likely that each can influence, and be influenced, by widespread regions of the cortex. of particular interest is the anterior cingulate and the left parietal cortex, both of which were prominent in the contrast of beau- tiful versus neutral. of these, the former is a large cortical zone that has often been associated with a variety of emotional states, such as romantic love (bartels and zeki a), plea- surable response to music (blood and zatorre ), and the viewing of sexually arousing pictures. although the activations obtained in these studies are not identical in location to the one that we report here, nevertheless the general site of activation is not un-interesting, in that it implies a connection between the esthetic sense and emotions. also interesting is the activation in the parietal cortex, in a region associated with spatial atten- tion (corbetta and shulman ). in our studies, this zone was only active in the comparison beautiful versus neutral, which may have placed a greater load on the attentional system. it is of course important to emphasize that, by its nature, an fmri study only reveals areas that are especially active during the paradigm used. it does not follow that undetected areas do not contribute in some way to the question under study, a point that is important in assessing all fmri results. hence it is possible that, though undetected, many more areas and cortical zones may have been active during the tasks that we have studied although experience with other systems, such as the motion and color system, indicates that the fmri method is a powerful guide to areas that are especially involved in a given task. it is also important to emphasize that the conclusions drawn here are derived from studies of visual beauty alone. only future studies using other stimuli and different experi- mental paradigms will tell whether these conclusions are true of other esthetic experiences—in music, poetry, literature, drama and other human endeavors that have had esthetic ap- peal. these results lead us to draw a distinction between two different kinds of brain activation. on the one hand is activity related to a particular types of stimulus— e.g., color or mo- tion—that engages principally a specific area specialized for processing that attribute—in these instances, v or v , respec- tively. this is so whether these stimuli are presented in isola- tion (bartels and zeki b; zeki et al. ) or as part of a more complex and freely viewed scene (bartels and zeki ). but unlike an attribute such as motion, which may or may not be present, beauty is part of a continuum, representing a value attributed to it by the brain, a value that, incidentally, can change from one viewing to another and differs between individuals. here we show that that value correlates with the intensity of activity in the same areas of the brain, and the shift fig. . averaged blood oxygen level-dependent signal changes taken across all subjects for the different painting categories (abstract, landscape, still life, portrait) and the response categories (beautiful, neutral, ugly) at medial orbito-frontal cortex (a), produced by the contrast of beautiful vs. ugly, and left motor cortex (b) by ugly vs. beautiful. regardless of painting categories, the signals in- crease for beautiful judgment at the orbito-frontal cortex and for ugly judgment at the motor cortex. fig. . psychophysiological interactions between the hottest voxel of the medial orbito-frontal cortex and the peak points (v , v , ffa, and ppa) revealed in category-specific analyses (see fig. ). the bars show the differ- ence in correlation between these areas in the context of portraits vs. non- portraits (a) and landscape vs. non-landscape (b). the panels show that the activity in the ffa correlates with activity in the medial orbito-frontal cortex in judgments of portraits, and with the activity in ppa for landscape judg- ments. c and d: averaged parameter estimates for ffa (c) and for ppa (d) for the response categories. each red bar shows se for each condition. h. kawabata and s. zeki j neurophysiol • vol • april • www.jn.org from beautiful to ugly does not engage different areas. that both beautiful and ugly stimuli modulate activity in the same cortical area(s) implies that it is the modulation of activity within those areas that correlates with the judgment of a stimulus as being beautiful or not. the distinction between the two types of activation is not, however, exclusive. for exam- ple, a graded response in area v has been observed when the visibility of a pattern of moving dots is increased by increasing the coherence of the motion of the dots (rees et al. ). as well, an increase in activity within an area can render the individual conscious of a stimulus (zeki and ffytche ). both naturally raise the primordial question of what determines the increase in activity. the activation of motor cortex is of special interest. it is not unique to our study. previous studies on the perception of ugly or fearful faces or other emotionally charged stimuli have also found either unilateral or bilateral activity here even though neither the activity nor its relevance is discussed in these papers. the area is activated, for example, in studies of trans- gressions of social norms (berthoz et al. ), of fear induc- ing visual stimuli (armory and dolan ), of congruent fearful voices and faces, and of anger (dougherty et al. ). it has also been observed during states of visual consciousness (pinns and ffytche ), when it succeeds activity in the occipital lobe. it would therefore seem that activation of motor cortex may be a common correlate not only of the perception of emotionally charged stimuli but also of stimuli of which we become conscious. why this should be so is conjectural, but it suggests that perception of visual stimuli in general and of emotionally charged stimuli in particular mobilizes the motor system, either to take some action to avoid the ugly or aversive stimulus or, in the case of beautiful stimuli, to make a response toward them. we are puzzled that perception of the beautiful does not mobilize the motor system to the same extent as the perception of the ugly. it is possible that the motor cortex has functions besides the one that is usually attributed to it. the parallel that we emphasize in the preceding text, be- tween strength of activity and conscious awareness of a stim- ulus, and strength of activity and its categorization into beau- tiful or not, is of more than passing interest. although much studied in the past two decades, no study has been able to pinpoint with certainty what constitutes consciousness in neu- ral terms. the same is true here, where we cannot be said to have been able to determine what constitutes beauty in neural terms. instead, the more meaningful question for both would currently seem to be the kantian question outlined in the introduction, namely what are the conditions implied by the existence of the phenomenon of beauty (or its absence) and of consciousness (or its absence) and what are the presuppositions that give validity to our esthetic judgments. in esthetics, the answer to both questions must be an activation of the brain’s reward system with a certain intensity. the definition of the activity of neural structures that are implicated in the judgment of beauty or in conscious experiences opens up the possibility of studying what in turn determines the strength of activity within the implicated structures. a c k n o w l e d g m e n t s we are grateful to drs. m. self and andreas 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multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. the documents may come from teaching and research institutions in france or abroad, or from public or private research centers. l’archive ouverte pluridisciplinaire hal, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. the strategic environment effect in beauty contest games nobuyuki hanaki, yukio koriyama, angela sutan, marc willinger to cite this version: nobuyuki hanaki, yukio koriyama, angela sutan, marc willinger. the strategic environment ef- fect in beauty contest games. games and economic behavior, elsevier, , , pp. - . � . /j.geb. . . �. �halshs- � https://halshs.archives-ouvertes.fr/halshs- https://hal.archives-ouvertes.fr the strategic environment effect in beauty contest games∗ nobuyuki hanaki† yukio koriyama‡ angela sutan§ marc willinger¶ november , abstract recent experimental studies have shown that observed outcomes deviate significantly more from the nash equilibrium when actions are strategic complements than when they are strate- gic substitutes. this “strategic environment effect” offers promising insights into the aggregate consequences of interactions among heterogeneous boundedly rational agents, but its macroe- conomic implications have been questioned because the underlying experiments involve a small number of agents. we studied beauty contest games with a unique interior nash equilibrium to determine the critical group size for triggering the strategic environment effect, and we use both theory and experiments to shed light on its effectiveness. based on cognitive hierarchy and level-k models, we show theoretically that the effect is operative for interactions among three or more agents. our experimental results show a statistically significant strategic environment effect for groups of five or more agents, establishing its robustness against the increase in the population size. keywords: beauty contest games, iterative reasoning, strategic substitutability, strategic com- plementarity jel classification: c , c . ∗we thank john duffy, cars hommes, aidas masiliunas, rosemarie nagel, charles noussair, ali ihsan ozkes, and participants at wehia and asfee , seminars at gate (lyon), iser (osaka), kyoto, southampton, and waseda for their comments and suggestions. a part of this research is financed by the conseil regional de bourgogne under “pari” grants, an ora-plus project “beam” (anr- -orar- ), investissements d’avenir (anr- -idex- /labex ecodec/anr- -labx- , and ucajedi anr- -idex- ). †université côte d’azur, cnrs, gredeg, france. e-mail: nobuyuki.hanaki@unice.fr ‡crest, ecole polytechnique, university of paris-saclay. e-mail: yukio.koriyama@polytechnique.edu §univ. bourgogne franche-comte, burgundy school of business-ceren. e-mail: angela.sutan@bsb- education.com ¶cee-m, univ montpellier, cnrs , inra, montpellier supagro, montpellier, france. e-mail: marc.willinger@umontpellier.fr introduction to what extent does non-rational behavior by (some) individuals affect aggregate outcomes? this question has regularly attracted the attention of leading scholars (see, for example, becker, ; conlisk, ; brock and hommes, ; fehr and tyran, , and references cited therein). a large body of experimental and empirical research has shown that people do not behave as rationally as often assumed by economic theory. this accumulated evidence has begun to influence theoretical developments, and there is now a rise in analyses based on “boundedly rational” agents in fields such as game theory, industrial organization, finance, and macroeconomics. despite these developments, many economists are still skeptical about the usefulness of explicitly considering the effects of bounded rationality when it comes to analyzing aggregate outcomes such as macroeconomic phenomena. one of the reasons for this skepticism is the belief held by many economists that can be summarized by an old statement from gary becker: “households may be irrational and yet markets quite rational” (becker, , p. ). that is, the deviations from rational behavior by many boundedly rational individuals will cancel each other out when we consider ag- gregate phenomena, thus, bounded rationality at the individual or household level does not matter much at the aggregate level. indeed, gode and sunder ( , ) show that even experimental markets consisting of zero-intelligence computer traders can exhibit high allocative efficiency when these zero-intelligence traders must operate under their respective budget constraints. however, other theoretical studies have shown that the existence of a few boundedly rational agents in a large population can have a larger-than-proportional impact on aggregate outcomes. for instance, akerlof and yellen ( a,b) and russell and thaler ( ), show instances where the existence of non-optimizing agents whose loss from non-optimization may be very small, can nevertheless have a large impact on equilibrium outcomes. de long et al. ( ) show that irrational noisy traders who take a large amount of risk can generate significant mispricing in the asset market and earn higher expected returns than rational investors. haltiwanger and waldman ( , , ) demonstrate that the behavior of boundedly rational agents can have a large influence, i.e. more than proportional to their population share, on the aggregate outcomes when the environment there are now many references for this including some very popular books such as ariely ( ) and kahneman ( ). an early collection of so-called “anomalies” in human behavior from the point of view of economic theory can be found in thaler ( ). for example, camerer ( ) is a comprehensive summary of behavioral game theory, shleifer ( ) is a nice introduction to behavioral finance, spiegler ( ) provides an overview of the growth of this type of research in the field of industrial organization, and duffy ( ) provides a survey of experimental analyses with macroeconomic implications. is characterized by strategic complementarity. in this paper, we follow up on the theoretical results from haltiwanger and waldman ( , , ). in their models, they considered two types of agents, naive and sophisticated, and showed that the aggregate outcome deviates more from the nash or rational expectations equilibrium in environments where agents’ actions are strategic complements than in environments where they are strategic substitutes. we call this phenomenon “the strategic environment effect,” a term that will be used in the rest of the paper. the underlying explanation for the strategic environment effect is the manner in which sophisti- cated agents best respond to the way they believe naive agents behave. in the presence of strategic complementarity, sophisticated agents have an incentive to mimic what they believe naive agents will do, and therefore amplifying the deviations from the equilibrium caused by naive agents, while in the presence of strategic substitutability they have an incentive to act in the opposite way, thus offsetting the deviations from the equilibrium caused by naive agents. several recent experiments provide support for the strategic environment effect in various con- texts. fehr and tyran ( ) studied price dynamics after a nominal shock in price-setting games. they found that the speed of adjustment to the new nash equilibrium is much slower under strate- gic complementarities than under strategic substitutabilities. heemeijer et al. ( ) and bao et al. ( ) studied the strategic environment effect in the framework of “learning-to-forecast” exper- iments (hommes et al., ). in “learning-to-forecast” experiments, the subjects’ task is to re- peatedly forecast the price of an asset with the knowledge that the forecasts, including their own, determine the price they are forecasting. although subjects are not informed of the exact relationship between their forecasts and the resulting price, both heemeijer et al. ( ) and bao et al. ( ) observed that the price forecasts and the resulting price both converge very quickly to the rational expectations equilibrium (ree) price under strategic substitutability. in contrast, under strategic complementarity, the forecasts and the resulting price often do not converge to the ree price, but instead follow large oscillations and exhibit patterns that are reminiscent of bubbles and crashes. potters and suetens ( ) considered the strategic environment effect on subjects’ ability to co- operate in an efficient but non-equilibrium outcome in duopoly games. they report significantly more cooperation under strategic complementarity than under strategic substitutability. suetens naive agents in their models are those who take some known default behavior, while sophisticated agents are those who try to maximize their payoffs knowing that there are both naive agents and other sophisticated agents like themselves. and potters ( ) show, based on a meta-analyses, that this finding holds not only for duopoly but also for oligopoly games. in a similar line of research, sutan and willinger ( ) experimentally studied two different one- shot beauty contest games (bcgs) with interior equilibria. in both experimental games, a group of subjects had to simultaneously choose a number between and . in the game called bcg+ which involved strategic complementarity, the winner was the subject who chose the number closest to (mean + ) where mean is the average number chosen by all other subjects (excluding oneself) of the group. in the second game called bcg−, which involved strategic substitutability, the winner was the one who chose the number closest to − mean, where mean is defined identically. the two games have the same unique nash equilibrium: iterated elimination of dominated strategies predicts that all players choose in both games. however, sutan and willinger ( ) observed significantly more subjects in bcg− choosing numbers closer to than in bcg+. unlike the experiments mentioned in the previous paragraph where subjects played the game repeatedly, subjects played a bcg once in the experiments by sutan and willinger ( ). their results, therefore, suggest that the strategic environment effect operates even when subjects are carrying out some kind of introspective strategic reasoning. while these experimental findings quite convincingly document the existence of a strategic envi- ronment effect, i.e., larger deviations of observed outcomes from the nash or the rational expectations equilibrium under strategic complementarity than under strategic substitutability, their robustness as well as their implications for macro phenomena are often questioned because these experimental results are based on interactions among a relatively small number of subjects. indeed, as duffy ( ) notes, “small numbers” is the most often raised concern when one tries to make inferences about macroeconomic phenomena based on the results obtained from a laboratory experiment. in the above-mentioned experimental studies, the sizes of groups were in potters and suetens ( ), in fehr and tyran ( ), in heemeijer et al. ( ) and bao et al. ( ), and in sutan and willinger ( ). because these studies also differ in many other respects, it is hard to obtain a clear picture of what drives the main result, although all of them evoke what we have defined as the in a typical guessing or beauty contest game (nagel, ; ho et al., ), a group of players simultaneously choose a number from within a given range, and the one who has chosen the number closest to p × mean, where < p < and mean is the mean of the numbers chosen by everyone, wins a fixed prize. by changing the target number to be p× mean + c where < c ≤ and < p < or − < p < , one can obtain a beauty contest game with an interior equilibrium. the first to experimentally study a beauty contest game with an interior equilibrium were güth et al. ( ). sutan and willinger ( ) also studied the version where mean is defined by the average number chosen by all the subjects in the group including oneself. the main result of the paper, however, is robust against this change. strategic environment effect. to understand how the strategic environment effect operates for the groups of different sizes, we theoretically and experimentally study the two versions of the one-shot beauty contest game with interior equilibria, bcg+ and bcg−, that were previously studied by sutan and willinger ( ). we focus on beauty contest games because this class of games has been an important tool in the development of behavioral game theory (camerer, ), particularly models that incorporate heterogeneity in the depth of strategic thinking among players, such as the level-k (nagel, ) and the cognitive hierarchy model (camerer et al., ). in addition, a beauty contest game can be seen as a canonical model of strategic thinking in speculative markets as first brought to the attention of economists by keynes ( , ch. ). furthermore, the more complex setups implemented in dynamic “learning-to-forecast” experiments mentioned above (hommes et al., ; heemeijer et al., ; bao et al., ) essentially boil down to a version of repeated beauty contest games with noise in which subjects are not informed about exactly how the target is defined (sonnemans and tuinstra, ). finally, given the constant sum nature of beauty contest games we consider, we can abstract away from issues related to subjects trying to coordinate on a non-equilibrium pareto- efficient outcome, which has been studied in the context of oligopoly games by huck et al. ( ), potters and suetens ( ), and friedman et al. ( ), among others. we first show, theoretically, that the strategic environment effect should be observed in our beauty contest games for any group sizes except for n = based on cognitive hierarchy (camerer et al., ) and level-k (nagel, ) models. experimentally, we vary groups of sizes systematically for n ∈{ , , , , , , }, and also consider a case of unknown size, i.e., the case where subjects are informed that the group size can be anything between and the total number of participants in the session (varied between to ) with equal probability. based on our experiment involving more than subjects, we find that there is no strategic environment effect for small group sizes, i.e. for groups of less than five interacting subjects. however, as soon as the group size is at least equal to five interacting subjects, we observe a statistically significant strategic environment effect. more keynes perceived a beauty contest as an inspiring illustration of the behavior at work within the stock market: smart traders do not try to guess what the fundamental value of a stock is, but rather what every other trader believes it is, and even smarter traders try to predict what the smart traders believe others believe about the fundamental value, and so on. the implication is that asset prices are not directly related to their fundamental values but to the first kth-order distribution of beliefs about what others believe, where k is the deepest level of thinking in the population of traders. güth et al. ( ) and nagel et al. ( ) study beauty contest games in which payoffs depend on the distance from the target number, and thus the nash equilibrium is the unique pareto-efficient outcome of the game. they report, however, the observed behavior in this version of the beauty contest games are not different from the contest version of the game considered in this paper. precisely, in groups of or more subjects, we observe a larger deviation from the nash equilibrium prediction under bcg+ than under bcg−, but not in smaller size groups. our experimental test of the strategic environment effect is quite strong because it allows for both between-subject and within-subject comparisons. therefore, the impact of the strategic environment effect on outcomes that was reported in earlier experiments involving relatively small group sizes is robust against an increase in group size but not against a decrease. our findings suggest that in a bcg environment, only a few interacting players are required in order to generate larger deviations from the rational expectations prediction under strategic com- plementarity than under strategic substitutability. this bolsters work done on other environments in which the strategic environment effect was observed, and which are relevant for macroeconomic issues such as price dynamics observed in financial markets (hommes et al., ; heemeijer et al., ; bao et al., ) and nominal rigidity (fehr and tyran, ). the rest of the paper is organized as follows: section provides theoretical predictions both for finite n and for the limit as n → ∞, section describes the experimental design, section summarizes the results of the experiment, and section offers a summary and concluding remarks. theoretical predictions in the beauty contest game (bcg), n players (n ≥ ) simultaneously choose a number between and . the player whose chosen number is closest to the target number wins a prize. in the case of a tie, one of the winners is randomly selected to receive the prize. we consider two variants of the game, bcg+ and bcg−. in bcg+, the players’ actions are strategic complements, whereas in bcg− their actions are strategic substitutes. in order to equalize the slopes of the best response functions in both games, and to avoid any influence of players’ choices on the target number, we set the target as the average number chosen by all players in the group excluding a player’s own choice. namely, in bcg+, the target for player i, tibcg+, is defined as tibcg+ = + ∑ j =i xj n− ( ) thus, in the case of -player games, the target number depends simply on the number chosen by the opponent. appendix b shows that, when the target is defined by the choices made by everyone in the group including one’s own, the slopes of the best reply function for bcg+ and bcg− are different for finite values of group size n. therefore, defining the target number based on the average number chosen by other players in the group allows us to study the strategic environment effect more clearly. where xj is the number chosen by player j. similarly, the target for player i in bcg−, tibcg−, is defined as tibcg− = − ∑ j =i xj n− . ( ) the unique nash equilibrium in both games is that all players choose . the nash equilibrium neither depends on the nature of the strategic environment nor on the number of players. let us first define the strategic environment effect. definition (strategic environment effect) we say that the strategic environment effect arises if the expected absolute deviation of choices from the nash equilibrium is larger when players’ actions are strategic complements than when they are strategic substitutes. in our games, let ỹ+i (resp. ỹ − i ) be the random variable derived from the distribution of choices normalized around the nash equi- librium in bcg+ (resp. bcg−). formally, we say that the (strong) strategic environment effect (see) arises if e [∣∣ỹ+i ∣∣] > e[∣∣ỹ−i ∣∣]. alternatively, one may define see based on the absolute deviation of the average choices. we say that the weak see arises if ∣∣e[ỹ+i ]∣∣ > ∣∣e[ỹ−i ]∣∣. in the rest of the paper, when we use the expression “strategic environment effect,” we refer to strong see as long as there is no ambiguity. as shown in footnote in the proof of theorem , strong see implies weak see in our games. because we will be focusing on the deviation from the nash equilibrium prediction to study the strategic environment effect, let yi := xi− denote player i’s strategy normalized around the nash equilibrium. then, the target functions are: τi+ = ȳ−i, τ i − = − ȳ−i ( ) where ȳ−i = ∑ j =i yj/ (n− ) is the average of the other players’ normalized strategies. our first result is for n = . the strategic environment effect is absent in this particular case, since it turns out that bcg+ and bcg− are equivalent games for n = . our explanation of the target number in the instructions given to subjects for the bcg+ game, which is + ∑ j =i xj n− , is different from the one used by sutan and willinger ( ), i.e., (∑ j =i xj n− + ) . we made this change to make the explanations of the target number in bcg+ and bcg− as symmetrical as possible. in addition, in our experiment, one of the winners was chosen randomly in the case of a tie, while in sutan and willinger ( ), winners received an equal share of the prize. this change was made to avoid the possibility that might especially arise in n = games where two subjects opt to choose a focal number to share the prize between them. proposition the strategic environment effect is absent for n = . proof. see appendix a. more generally for n ≥ , the following lemma turns out to be useful. lemma let κ = (n− ) and yij = ∑ h =i,j yh. (i) in bcg+, player i wins if and only if yi lies between yj and −yj + κ −κyij for ∀j = i. (ii) in bcg−, player i wins if and only if yi lies between yj and −yj − κ +κyij for ∀j = i. proof. see appendix a. remark the equivalence of bcg+ and bcg− for n = is obtained as a corollary, since the yij term disappears. . asymptotic properties in this subsection, we analyze asymptotic properties of the cognitive hierarchy models that relax the following two assumptions used in the equilibrium analyses: (i) all players have infinite depth of reasoning, and (ii) this fact is common knowledge, and it also takes into account heterogeneity in depth-of-strategic thinking among players. for each k ≥ , a level-k player holds a belief over the level of the other players. two models which draw the most attention in the literature are (i) the level-k model (nagel, ) in which each level-k player assigns the entire probability on level-(k − ), and (ii) the poisson cognitive hierarchy model (camerer et al., ) in which beliefs are truncated poisson distributions. more generally, for any distribution function (ph) ∞ h= over n with p > , a cognitive hierarchy model can be defined, assuming that each level-k player holds a belief induced by the truncated distribution( ph p +···+pk− )k− h= for k ≥ . we say that a cognitive hierarchy model is non-degenerate if ph > for ∀h. our analyses here focus on non-degenerate cognitive hierarchy model. see appendix c for the level-k model. below, we first consider the best response of a player holding a belief such that each of the other players’ strategies is independently and identically distributed. we then compare asymptotic properties between the bcg+ and the bcg− games. proposition suppose that player i holds a belief such that yj is independently and identically distributed for ∀j = i, and let µ be the mean value of the distribution. as n → ∞, player i’s best response converges to µ (resp. − µ) in the bcg+ (resp. bcg−) game. proof. see appendix a. theorem as n goes to infinity, the strong strategic environment effect arises under any non- degenerate cognitive hierarchy model. proof. let µ be the mean value of the level- strategy. suppose µ = , since we are interested in the deviation from the nash equilibrium behavior. without loss of generality, assume µ < . for a non-degenerate cognitive hierarchy model, let z+chk (resp. z − chk) be the limit level-k strategy as n →∞ in the bcg+ (resp. bcg−) game. with a slight abuse of notation, let z±ch = µ . since the strong strategic environment effect is defined by the expected absolute distance from the nash equilibrium, it is sufficient to show that ∣∣z+chk∣∣ ≥ ∣∣z−chk∣∣ for ∀k ≥ with strict inequality for ∀k ≥ , implying that ∞∑ k= pk ∣∣z+chk∣∣ > ∞∑ k= pk ∣∣z−chk∣∣ ( ) for any non-degenerate (pk) ∞ k= . proposition implies that, for k ≥ , z+chk = k− ∑ h= ph p + · · · + pk− z+chh, z−chk = − k− ∑ h= ph p + · · · + pk− z−chh. in particular for k = , we have ∣∣z+ch ∣∣ = ∣∣z−ch ∣∣ = |µ |. now, we claim that ∣∣z+chk∣∣ > ∣∣z−chk∣∣ for ∀k ≥ . to see that, remember z+ch = µ < and z+ch = µ . since z + chk is of a weighted average of ( z+chh )k− h= for k ≥ , we have: µ < z + ch < z + ch < · · · < . even though the level- strategy is often taken as a mixed strategy, what only matters here is the expected value. strong see implies weak see. as shown below, z+ chk < for ∀k ≥ and z− ch < < z− ch , which implies ∑∞ k= pk ∣∣∣z+chk∣∣∣ = ∣∣∣∑∞k= pkz+chk∣∣∣ and ∑∞k= pk ∣∣∣z−chk∣∣∣ > ∣∣∣∑∞k= pkz−chk∣∣∣. then, ( ) implies that∣∣∣∑∞k= pkz+chk∣∣∣ > ∣∣∣∑∞k= pkz−chk∣∣∣. since all terms of z+chh have the same (negative) sign, the triangle inequality holds with equality: ∣∣z+chk∣∣ = ∣∣∣∣∣ k− ∑ h= ph p + · · · + pk− z+chh ∣∣∣∣∣ = k− ∑ h= ph p + · · · + pk− ∣∣z+chh∣∣ . ( ) on the other hand, ∣∣z−chk∣∣ = ∣∣∣∣∣ k− ∑ h= ph p + · · · + pk− z−chh ∣∣∣∣∣ ≤ k− ∑ h= ph p + · · · + pk− ∣∣z−chh∣∣ . ( ) since ph > for ∀h, the last inequality is strict unless all terms of z−chh have the same sign. since z−ch = µ < and z − ch = − µ > , the inequality is strict for ∀k ≥ . in particular, ∣∣z−ch ∣∣ < ∑ h= ph p + p ∣∣z−chh∣∣ . since ∣∣z−chh∣∣ = ∣∣z+chh∣∣ for h = , , we have: ∑ h= ph p + p ∣∣z−chh∣∣ = ∑ h= ph p + p ∣∣z+chh∣∣ = ∣∣z+ch ∣∣ where the last equality holds by ( ). in sum, we have ∣∣z−ch ∣∣ < ∣∣z+ch ∣∣. the claim is true for k = . for the sake of induction, suppose ∣∣z−chh∣∣ < ∣∣z+chh∣∣ for h = , · · · ,k with k ≥ . then, ∣∣z−chk+ ∣∣ < k∑ h= ph p + · · · + pk ∣∣z−chh∣∣ < k∑ h= ph p + · · · + pk ∣∣z+chh∣∣ = ∣∣z+chk+ ∣∣ . the first inequality holds by ( ) with strict inequality, since k ≥ . the second inequality holds by assumption. the last equality holds by ( ). remark the result obtained in theorem still holds even for the cases in which the level- strategies differ between bcg+ and bcg−, as long as their means have the same distance from the nash equilibrium. in our games, pure strategy (resp. ) may be a focal point of bcg+ (resp. bcg−), because they appear explicitly in the definition of the target number. since the nash equilibirum is in both games, the distance has the same value , and thus theorem predicts the strategic environment effect for large n under any non-degenerate cognitive hierarchy model. remark the result does not depend on the specific value of the coefficient . for any coefficient smaller than , the same argument holds. . the strategic environment effect for finite n for finite n, it is a rather tedious task to provide an analytical form which precisely describes the best reply of a player. a naive approximation of the best reply is the mid-point of the interval specified in lemma . in the bcg+ game, the mid-point is: β+n := ( yj −yj + κ −κ yij ) = κ −κ yij = (n− ) (n− ) − ȳ+ij, where ȳ+ij is the average of the strategies excluding players i and j. similarly in the bcg− game, β−n := ( yj −yj − κ + κ yij ) = − κ + κ yij = − (n− ) (n− ) + ȳ−ij. therefore, ∣∣∣∣β+nβ−n ∣∣∣∣ = + κ −κ ∣∣∣∣∣ ȳ + ij ȳ−ij ∣∣∣∣∣ = (n− ) + (n− ) − ∣∣∣∣∣ ȳ + ij ȳ−ij ∣∣∣∣∣ . whether the strategic environment effect would appear thus depends approximately on whether the product of these two ratios is larger than one or not. note that the first term satisfies: (n− ) + (n− ) − > ( ) and that the ratio is decreasing in n and converges to one from above as n → ∞. this inequality suggests that the strategic environment effect appears for small n and fades away as n increases, as long as the ratio ∣∣ȳ+ij/ȳ−ij∣∣ is close to one. to see how the ratio changes for different n, we run monte carlo simulations. table shows the normalized strategies y = x− of level , and under a poisson cognitive hierarchy model with a mean level . the level- strategy is the uniform distribution. the limit values as n →∞ are computed using the asymptotic property stated in proposition . the effect implied by ( ) is most visible among the level- strategies, as they are defined as the best reply to the level- strategy, and are the same for both the bcg+ and the bcg− games random samples are obtained from to million iterative draws. for small n, a larger number of draws are necessary in order to avoid ambiguity caused by the discontinuity of expected payoff functions. see also discussions in the following paragraphs. the program is written in matlab. the code is available from authors upon request. table : normalized strategies x − in bcg+ and bcg− under a poisson ch model with mean level . grid search with ∆ = . . bcg+ bcg− n ch ch ch ch ch ch − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . . . − . − . − . . − . − . − . − . . − . − . − . − . − . . − . − . − . − . − . . − . − . − . − . − . . − . − . ... ... ... ... ... ... ... − . − . − . . − . − . ... ... ... ... ... ... ... − . − . − . . − . − . ... ... ... ... ... ... ... ∞ − . − . − . . − . − . (hence ∣∣ȳ+ij/ȳ−ij∣∣ = ). for level and higher, the strategic environment effect is observed except for n = . note that all strategies in the bcg+ game have the same (negative) sign. this is due to strategic complementarity, which implies that the best reply has the same sign as the deviation generated by the level- strategy. on the other hand, the strategies in the bcg− game have both negative and positive signs, due to the negative slope of the best reply function which represents strategic substitution. as a consequence, players of level or higher have a belief such that the aggregate deviations generated by other players would offset each other, and thus the best reply strategy is closer to the nash equilibrium in the bcg− game than in the bcg+ game (i.e. ∣∣ȳ+ij/ȳ−ij∣∣ > ). therefore, the strategic environment effect is expected to appear for level or higher. for small n, however, several effects coexist, and the critical value of n for which the strategic environment effect appears is not clear. figure shows the expected payoff of a level- player in both bcg+ and bcg− games for different n. we observe that the best reply is attained at the point where the payoff function is discontinuous for small n. since the level- strategy is pure, the associated mass probability causes such discontinuities. for any n, each player holds a belief that other players’ strategies are drawn from a composite of poisson distribution, uniform distribution, and a pure strategy. as n becomes large, combinations of distributions smooth out the expected payoff for large n, which is visible in figure . however, the discontinuity remains problematic for small n. if the discontinuity is indeed the reason for these puzzling outcomes for small n, in particular for n = , by smoothing the strategy choices by relaxing the assumption of perfect best reply, we would obtain the strategic environment effect even for n = . as we show in the next subsection with a logistic poisson cognitive hierarchy (lch) model, this is indeed the case. . a better-response model we relax the “best response” assumption by considering a logistic poisson ch (lch) model, where players’ choices depend proportionally on their expected payoffs: options with higher expected pay- offs are chosen with higher probabilities. in order to facilitate the presentation and numerical computations of the lch model, we assume that players (in bcg+ and bcg−) can only choose integer numbers between and . a level- player chooses an integer between and with uniform probability. level- players assume that level- players choose randomly with uniform probability and compute the expected payoff for each of the integers between and . let e (π(x)) be the expected payoff for a level- player if he or she chooses integer x. then, the level- player chooses an integer s according to the probability pi (s) = eλe (π(s))∑ x e λe (π(x)) ( ) stahl and wilson ( ) proposed such a model with a cognitive hierarchy structure to capture the observed behavior of subjects in symmetric by games. it has been shown that these models that rely on imperfect best response, or so-called “better response” assumptions (rogers et al., ), provide a more suitable fit to the experimental outcomes than models that assume perfect best response (see, among others, mckelvey and palfrey, ; goeree and holt, ; rogers et al., ; breitmoser, ). the assumption of perfect best response in level-k and ch models has therefore been relaxed in favor of the assumption of “better response” in the noisy introspection (goeree and holt, ) and the truncated heterogeneous quantal response (rogers et al., ) models, respectively. indeed, goeree et al. ( ) showed that the noisy introspection model predicts the experimental outcomes much better than the level-k model in games that extend the - money request game proposed by arad and rubinstein ( ). similarly, breitmoser ( ) showed that the noisy introspection model fits better the data of the beauty contest experiments compiled by bosch-domènech et al. ( ) than the level-k model. in a similar line, bosch-domènech et al. ( ) introduce noise in an extended level-k model that includes nash players (i.e., level-∞) assuming that agents’ choices follow level-specific beta-distributions, and find that the model captures well the data of bosch-domènech et al. ( ). figure : the expected payoff of a ch player for bcgn+ (dashed) and bcgn− (solid). where λ is a parameter that governs the sensitivity of players’ choices to the variation in their expected payoffs. if λ = , the level- player chooses just like a level- player, i.e., pi (s) = / whatever the number s considered. if λ →∞, the probability distribution becomes degenerate and players select the integer with the highest expected payoff with probability one, i.e., players tend to perfect best reply. a level- player considers the probability of each of his or her opponents being level- and level- , with respective choice probabilities p j (s) = / and p j (s) defined in ( ) above. given such computed expected payoffs for each x, e (π(x)), the level- player chooses integer l with probability pi (l) = eλe (π(l))∑ x e λe (π(x)) . ( ) the probability of choosing an integer for level- and above is defined iteratively in a similar manner. for the numerical exercise reported below, in each bcg and group size n, we compute the exact expected payoffs from choosing each integer for agents of level to for a given value of λ, assuming that an agent obtains a payoff of if he wins. in case of ties, we assume that the payoff of is given to one of the winners who is randomly chosen (that is, the expected payoff is number of winners ). we then aggregate the probabilities of these levels of agents choosing each integer by taking the weighted average of the probabilities where the weight is based on the truncated poisson distribution with mean assuming the maximum level is . figure shows the mean |x − | in bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } in lch. we assume a mean level of and λ = . . the strategic environment effect is observed for all the values of n we have considered except for n = . thus, as we have hypothesized, the absence of the strategic environment effect in n = case considered in the previous subsection was driven by the strong assumption of best reply. before explaining our experimental design, a remark about existing experiments on -player beauty contest games is in order. grosskopf and nagel ( ) and chou et al. ( ) studied a - λ may be level dependent. in this paper, however, we assume the same λ for all the levels above . the program is written in c++. the source code is available from the author upon request. we compute the exact expected payoff for each integer. in order to do so, we need to consider all the possible combinations of integers chosen by n − other agents. this makes computation time grow as (n− ) without careful programming. we have implemented this computation differently so that computing time grows roughly as hn− . even with this implementation and making use of the parallel computation, however, it was not possible for us to go beyond n = with a reasonable computing time. unless λ is too small, so that choices are not too noisy, we obtain qualitatively the same result. the results are also robust for the other mean levels, such as . and . . see appendix d. n meanÈx- È figure : mean |x − | in bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } according to lch. we assume mean level is and λ = . . player bcg for which the target number was mean, where mean includes the player’s own choice. this -player bcg has the special feature that “whoever chooses the lower number wins.” therefore, it is relatively easy to realize the existence of a weakly dominant strategy in this game, i.e., to choose zero. grosskopf and nagel ( ) report, however, that despite this special feature about % of their subjects chose numbers larger than zero. chou et al. ( ) argue that the subjects do not realize the special feature of the game. in addition, grosskopf and nagel ( ) found that the numbers chosen in their -player bcg are larger than the numbers chosen by subjects who were involved in bcg games with groups of size n > . to better understand this rather puzzling result, nagel et al. ( ) conducted a new experiment of a -player bcg with a distance payoff function: both players were paid an amount that depended on the distance of their chosen number and / of the mean. thanks to this particular payoff function, is the unique dominance solvable equilibrium which is also pareto-efficient. furthermore, the equilibrium solution is reached after iterated elimination of strictly (and not weakly) dominated strategies. however, in the data reported by nagel et al. ( ), the distribution of the chosen numbers with the distance function does not differ from those of the standard -player bcg considered in grosskopf and nagel ( ). moreover, the spikes are at exactly the same numbers for both treatments. according to the authors, in a -player bcg subjects are unable to find the dominant strategy of the game and do not take into account their influence on the mean. furthermore, they probably focus on some focal numbers. in our -player bcgs, as one easily could infer from the proof of proposition above, there is also a dominant strategy, i.e., to choose . however, this dominant strategy is far more difficult costa-gomes and crawford ( ) also studied -player bcgs, but most of the games they studied are asymmetric in that the strategy sets and/or the target numbers for the two players differed. furthermore, in their games, the payoff declined continuously based on the distance from the target such that the equilibrium was reached by iterated elimination of strictly dominated strategies. to find compared to the games considered in the aforementioned studies. in addition, the target for a subject is not influenced by his or her own choice. furthermore, our focus is to investigate the strategic environment effect, which is different from these earlier studies on -player bcgs. experimental design as noted in the previous section, we consider two beauty contest games, bcg+ and bcg−, while varying the size of the group n. we denote bcg+ and bcg− games with group size of n by bcgn+ and bcgn−, respectively. we systematically vary the group size n and consider n ∈ { , , , , }. we also consider n ∈ { , } to check whether the result of sutan and willinger ( ) is robust against the small differences in experimental design between our experiment and their experiment discussed in footnote (n = ), as well as to check whether our results continue to hold when the group size becomes even larger (n = ). furthermore, we consider situations where subjects did not know the exact group size except that it could be any size between and the total number of subjects involved in a session with an equal probability. we call this treatment uncertain n. with the uncertain n treatment, we aim to investigate the strategic environment effect when the size of the group may be larger than without the subjects knowing the exact size. in many empirically relevant situations (e.g. financial markets), it is often the case that individuals do not know the exact number of agents who interact in a large group. although we have not derived any theoretical predictions regarding the uncertain group size case, one may extrapolate from the analyses above that as long as subjects believe that the size of the group is likely to be greater than two, the strategic environment effect is expected to appear. in our experiment, each subject chose an integer between and , and the subject whose choice was closest to the target number won a fixed prize ( euros). in the case of a tie, as described in the previous section, one of the winners was chosen at random to receive the prize. we have opted to restrict the choice set to integers between and , instead of real numbers, in order to make our experimental observations comparable to the predictions of the lch model discussed in section . . furthermore, because only a few subjects chose non-integers in sutan and willinger ( ), we expected that this restriction would not greatly influence the results. in each experimental session, subjects played both bcgn+ and bcgn− with the same n. in please see appendix f for the english translation of the instructions. table : summary of treatments group size number of subjects in number of subjects in bcg−→ bcg+ bcg+ → bcg− uncertain n number of participants { , , , , } { , , , , } in each session of uncertain n note: the number of participants of a session is the maximum possible group size for the session in the uncertain treatment. half of the sessions, subjects played bcgn+ first, and in the other half, they played bcgn− first. subjects were informed that they would play two games, called game and game , but they were not informed about the nature of game when playing game . furthermore, no feedback regarding the outcome of game was provided before playing game . at the end of game , one of the two games was chosen randomly for the payment. results subjects were recruited from across the campus of the burgundy school of business between septem- ber and october . in total, student subjects were involved in our experiment. each subject participated in only one experimental session. on average, a session lasted for about minutes. experiments were not computerized and were carried out with papers and pens. table summarizes the number of subjects involved in each treatment. in the uncertain n treatment, the number of participants in one session (thus, the maximum group size) varied between and , while the actual group size selected varied between and . although we have not explicitly informed subjects about the exact number of participants in the session they have participated, subjects could have a rough estimate by seeing the number of subjects gathering for the session. . between-subject analysis we start with a comparison of the subjects’ choices for game in order to derive between-subject results. figure shows the empirical cumulative distribution (ecd) of the absolute deviation of chosen numbers, x’s, from the nash equilibrium prediction (|x − |) for bcgn− (in solid lines) and bcgn+ (in dashed lines) for all the tested values of n. it also reports the mean and the standard deviation of |x− |. the p-value below each panel is based on a two-sample permutation test (two-tailed). one can easily see from figure that for small group sizes, i.e. for n ∈{ , , }, |x− | does not significantly differ between bcgn+ and bcgn−. the difference, however, becomes statistically significant for larger and uncertain group sizes, i.e., n ∈{ , , , , uncertain}. observation (between subjects): the absolute deviations of the choices from the nash equi- librium are not significantly different between bcgn+ and bcgn− for n < , but for n ≥ , and for the case of an uncertain group size, it is significantly larger in bcgn+ than in bcgn−. thus, the strategic environment effect becomes statistically significant for n ≥ but not for n < . . within-subject analysis we now consider the choices made by each subject in the two bcgs. our subjects played both bcgn+ and bcgn− with the same group size n for each game. some of our subjects played bcgn+ first and then bcgn−, while others played in the opposite order. we are primarily interested in whether the absolute deviations of the chosen numbers from the nash equilibrium ( ) are larger in bcgn+ than in bcgn−, within subjects. thus, for each subject i we define ∆i|x− | ≡ |xibcg+ − |− |x i bcg− − | where xibcg+ (x i bcg−) is the number subject i has chosen in bcgn+ (bcgn−). ∆ i|x− | is the difference in the absolute difference between the numbers subject i has chosen and in bcgn+ and bcgn−. table shows the means and the standard deviations of ∆i|x − | for various n. we have figure in appendix e shows the histogram of chosen numbers in bcgn− and bcgn+ for all values of n. the permutation tests are conducted using the stata package provided by kaiser ( ). n = n = Èx- È . . . . . . ecd Èx- È . . . . . . ecd bcg −: . ( . ) bcg −: . ( . ) bcg +: . ( . ) bcg +: . ( . ) p = . p = . n = n = Èx- È . . . . . . ecd Èx- È . . . . . . ecd bcg −: . ( . ) bcg −: . ( . ) bcg +: . ( . ) bcg +: . ( . ) p = . p < . n = n = Èx- È . . . . . . ecd Èx- È . . . . . . ecd bcg −: . ( . ) bcg −: . ( . ) bcg +: . ( . ) bcg +: . ( . ) p < . p < . n = n uncertain Èx- È . . . . . . ecd Èx- È . . . . . . ecd bcg −: . ( . ) bcguncertain−: . ( . ) bcg +: . ( . ) bcguncertain+: . ( . ) p = . p < . figure : the empirical cumulative distribution of the absolute deviations from the nash equilibrium predictions |x − | for bcgn+ (dashed) and bcgn− (solid). mean |x − | and its standard deviation in the parentheses are also reported. p-values are based on a two-sample permutation test (two-tailed) with the null hypothesis that |x− |s are the same between bcgn+ and bcgn− for each n. table : mean and standard deviation of ∆i|x− | ≡ |xibcg+ − |− |x i bcg− − | for various n n bcgn+ → bcgn− bcgn− → bcgn+ p-value - . ( . ) . ( . ) . . ( . ) - . ( . ) . . ( . ) . ( . ) . . ( . ) . ( . ) . . ( . ) . ( . ) . . ( . ) . ( . ) . . ( . ) . ( . ) . uncertain . ( . ) . ( . ) . i standard deviations are in parenthesis. ii p-values are based on the two-sample permutation test with the null hypothesis that ∆i|x− | is the same in bcgn+ → bcgn− sessions than in bcgn− → bcgn+ sessions. separated the sessions according to the order in which the two bcgs are played. assuming that subjects “learn” to choose a number closer to the nash equilibrium in the second game that they play than in the first game, ∆i|x− | tends to be larger for those subjects who played bcg+ first than those who played bcg− first. the results of the two-sided permutation tests, reported in the last column of table , show, however, that ∆i|x− | is significantly different between the two orderings at % significance level only for n = . thus, for the analysis below, we pool the data from all the sessions. we run a linear regression with ∆i|x− | being the dependent variable and various group size dummies being the independent variables. the results of the regression are reported in table . as one can see from the estimated coefficients for group size dummies, the strategic environment effect (measured by ∆i|x − |) is significant and positive for n ≥ and uncertain n, but not for n ∈{ , , }. this result confirms observation of the between-subject analysis. we also tested whether the estimated strategic environment effects are significantly different within the subsamples of group sizes n ∈{ , , } and n ∈{ , , , , uncertain}. the results of the f-tests show that they are not significantly different within the two groupings. p-values are . for n ∈{ , , } and . for n ∈{ , , , , uncertain}. observation (within subjects): for n ≥ , absolute deviations of the choices from the nash equilibrium are significantly larger in bcgn+ compared to bcgn−, but for n < they are not. thus, the statistically significant strategic environment effect is observed for n ≥ but not for n < . table : ols regression ∆i|x− | ≡ |xibcg+ − |− |x i bcg− − | on various size dummies group size dummy coefficient std. err. p-value . . . . . . . . . . . < . . . < . . . < . . . < . uncertain . . < . no. obs. = . r = . i dummy variables take a value of for the correspond- ing group size, and otherwise. ii there is no constant term in this regression. discussion and conclusion we defined the “strategic environment effect” as the tendency for agents to deviate significantly more from the nash or rational expectations equilibrium when their actions are strategic complements than when they are strategic substitutes. its existence has been shown theoretically by haltiwanger and waldman ( , , ), and later confirmed experimentally by fehr and tyran ( ), heemeijer et al. ( ), potters and suetens ( ), and sutan and willinger ( ). the strategic environment effect provides promising insights into the aggregate consequences of interaction among heterogeneous boundedly rational agents, but its macroeconomic relevance has been often questioned because the above-mentioned experiments involved groups with small numbers of interacting agents (up to ). this criticism has led to our research questions: does the strategic environment effect depend on population size? if so, how? as it is useful to provide robust evidence about the relevance of the strategic environment effect for addressing macro phenomena, we investigated this question theoretically and experimentally by studying variants of the beauty contest game that have the same unique interior solution, and by systematically varying the size of the group of interacting subjects. the two different beauty contest games we have considered involved either strategic substitutes or strategic complements. both games are dominance solvable and have the same interior equilibrium that is reached after the same number of iterated eliminations of weakly dominated strategies. our theoretical analyses show that the strategic environment effect is observed for any group size but . equipped with these results, in our experiment, we have considered eight different group sizes: n ∈ { , , , , , , , uncertain}. except for the treatment with uncertain n, subjects were perfectly aware of the size of their group. for the uncertain n treatment, subjects were informed that the size of the group could be anything between and the number of subjects involved in the session with equal probability. we observed a statistically significant strategic environment effect when the group size was n ≥ as well as for uncertain n. however, such an effect was not observed for smaller-sized groups (n < ). this observation is coherent with our theoretical result that the effect should persist for large n. our findings establish a critical threshold required for population size to trigger the strategic environment effect in a bcg environment, and provide new evidence that experimental findings of the strategic environment effect are robust against an increase in the group size. other recent studies show that it is not only in the one-shot bcg where the experimental findings on the strategic environment effect are robust against an increase in the group size. bao et al. ( ) and kopányi- peuker et al. ( ) observe, in the presence of strategic complementarity, large deviations from the rational expectations equilibrium with large group sizes ( to for the former and more than for the latter) in the framework of a learning-to-forecast experiment. although similar robustness checks against increasing group sizes should be carried out in other experimental setups, our results as well as those by bao et al. ( ) and kopányi-peuker et al. ( ) indicate that the experimental findings on the strategic environment effect, even if they are based on the interactions among a small number of subjects, may provide a major insight for macro phenomena. the gap between the theoretical prediction and our experimental results for very small group sizes, namely for n = and n = , however, leaves us with some puzzles. as one can see from the histogram of chosen numbers reported in figure in appendix e, on one hand, for small group sizes, choices are distributed rather uniformly between and excepts for spikes at and in both bcg+ and bcg−. for larger groups, on the other hand, they are distributed more around in bcg− while they continue to be rather uniformly distributed in bcg+. these observations are not fully captured by our theoretical analyses. a possible reason for not observing the strategic environment effect experimentally for these small groups size is subjects’ thought processes being different in very small groups from those in larger groups. this hypothesis can be investigated by eliciting subjects’ thought processes in small and in large groups, for example, based on the experimental method recently proposed by agranov et al. ( ) that elicits the dynamics of subjects’ choice processes in an incentivized manner. such an analysis would also shed light on another interesting question. in the current paper, the strategic environment effect is a result of aggregating choices made by players of varying degrees of strategic sophistication. in our theoretical analyses, players are basically applying the same type of reasoning in the two strategic environments. it is, however, possible that these two strategic environments induce players to think differently about the problem itself, as suggested by a recent neuroscience study (nagel et al., ) that compares brain activity when subjects are playing a critical mass game (with strategic complementarity) and an entry game (with strategic substitution). however, the two games nagel et al. ( ) consider have different sets of nash equilibria. there are a unique symmetric mixed strategy nash equilibrium and many asymmetric pure strategy nash equilibria in the market entry game, while there are two symmetric pure strategy nash equilibria and a unique symmetric mixed strategy nash equilibrium in the critical mass game. furthermore, in the critical mass game, level- and above all behave in the similar manner (i.e., no thinking higher than level- is invoked), while in the entry game, their behavior differ (i.e., higher order thinkings are invoked). thus, it is not clear whether the differences in neural activity between the two games that nagel et al. ( ) report are due to the difference in the nature of the strategic environment (complements vs substitutes) or due to these other differences. because the two bcgs we have considered do not differ except for the nature of the strategic environment, our setting could clarify this point. finally, one may ask whether our finding can be extended to other settings, such as oligopoly games, where earlier studies reported the strategic environment effect (potters and suetens, ). in oligopoly games, however, it is well known that the larger a group is, the more difficult it is to achieve the cooperative outcome (huck et al., ). it is possible that such a negative group size effect on the subjects’ ability to coordinate on the cooperative outcome dominates the strategic environment effect as we increase the group size. however, the precise relationship between these two effects is not known. thus, it would surely be fruitful future research to consider this question both theoretically and experimentally. references agranov, m., a. caplin, and c. tergiman ( ): “naive play and the process of choices in guessing games,” journal of economic science association, , – . akerlof, g. a. and j. l. yellen ( a): “can small deviations from rationality make signifi- cant differences in economic equilibria?” american economic review, , – . ——— ( b): “a near-rational model of the business cycle, with wage and price inertia,” quarterly journal of economics, , – . arad, a. and a. rubinstein ( ): “the - money request game: a level-k reasoning study,” american economic review, , – . ariely, d. 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( ): the winner’s curse: paradoxes and anomalies of economic life, new york, ny: free press. a proofs a. proof of proposition proof. suppose n = . by definition, the distances to the target in bcg+ and bcg− are respectively: d+i = ∣∣∣∣yi − yj ∣∣∣∣ and d−i = ∣∣∣∣yi + yj ∣∣∣∣ , for i = j. player i wins against player j in bcg+ if and only if: d+i < d + j ⇔ ∣∣∣∣yi − yj ∣∣∣∣ < ∣∣∣∣yj − yi ∣∣∣∣ ⇔ ( yi − yj ) < ( yj − yi ) ⇔ y i < y j . in bcg−, player i wins against player j if and only if: d−i < d − j ⇔ ∣∣∣∣yi + yj ∣∣∣∣ < ∣∣∣∣yj + yi ∣∣∣∣ ⇔ ( yi + yj ) < ( yj + yi ) ⇔ y i < y j . the above equivalences show that the winner is the same and thus the payoffs are the same between bcg+ and bcg−, given the strategy profile (y ,y ). therefore, the two games are equivalent. trivially, there is no strategic environment effect for n = . a. proof of lemma proof. let y−i = ∑ h =i yh. by ( ), the target functions are τ + i = κy−i, τ − i = −κy−i. hence, the distance functions are: d+i = |yi −κy−i| , d − i = |yi + κy−i| . hence, d+i < d + j ⇔ (yi −κyj −κyij) < (yj −κyi −κyij) , d−i < d − j ⇔ (yi + κyj + κyij) < (yj + κyi + κyij) . player i wins against j in bcg+ iff: (yi −κyj −κyij) < (−κyi + yj −κyij) ⇔ y i + κ y j − κyiyij + κ yjyij < κ y i + y j + κ yiyij − κyjyij ⇔ ( −κ ) (yi −yj) ( yi + yj − κ −κ yij ) < ⇔ (yi −yj) ( yi + yj − κ −κ yij ) < . in the last equivalence, we used −κ > . similarly in bcg−, d−i < d − j ⇔ (yi −yj) ( yi + yj + κ + κ yij ) < . a. proof of proposition proof. note that κ ±κ yij = (n− ) ± (n− ) (n− ) ȳij = (n− ) (n− ) ± ȳij where ȳij = yij/ (n− ) is the average of the strategies excluding players i and j. by the law of large numbers, as n goes to infinity, ȳij converges to the mean value µ. therefore, as n → ∞, κ ±κyij converges to µ. by lemma , in the bcg+ game, player i wins if and only if yi lies between yj and −yj + κ −κyij for ∀j = i. since the average of these values converges to µ for each j, player i’s best response converges to µ. similarly, player i’s best response converges to − µ in the bcg− game. b the definition of the target and the slope of the best re- sponse functions let us consider bcgn+ and bcgn− where the winner is the one closer to the following target based on the mean including the player. that is, for bcgn+, the target, t, is t = + ∑ j xj n , and for bcgn−, it is t = − ∑ j xj n where xj is the number chosen by subject j in the same group. ignoring the inequality of the winning condition, a bit of algebra will lead us to have the following best response functions. in bcgn+ x(x−i) = n n− + n− n− ∑ j =i xj n− , and in bcgn− x(x−i) = n n + − n− n + ∑ j =i xj n− . here if n →∞ then, we have n− n− = n− n+ = so that the slope of the best response functions will be the same between bcgn+ and bcgn−, but with a small group size n, they are quite different. for any n, the absolute value of the slope is smaller in bcgn− than in bcgn+. thus, to be able to study the effect of the group size n, as well as the difference in the nature of the strategic interaction between bcgn+ and bcgn− without them influencing the slope of the best response functions, one needs to define the target based on the average choice by the other players in the group, as we have done in this paper. c the level-k model consider the (deterministic) level-k model, in which each level-k player best replies against the level-(k − ) strategy. as in theorem , let (ph) ∞ h= be the level distribution among the players. proposition the weak strategic environment effect arises asymptotically in the level-k model. proof. let µ (< wolog) be the mean value of the level- strategy. let z + lk (resp. z − lk) be the limit level-k strategy as n →∞ in the bcg+ (resp. bcg−) game. by proposition , z+lk = ( )k µ and z − lk = ( − )k µ for ∀k ≥ , ( ) which implies ∣∣z+lk∣∣ = ∣∣z−lk∣∣ for ∀k ≥ , then, the expected absolute deviation from the nash equilibrium is the same in the bcg+ and in the bcg− games: ∞∑ h= ph ∣∣z+lk∣∣ = ∞∑ h= ph ∣∣z−lk∣∣ , that is, the strong strategic environment effect is absent asymptotically. however, ( ) implies that µ < z + l < z + l < · · · < and µ < z − l < z − l < · · · < < · · · < z − l < z − l . therefore, we have: ∣∣∣∣∣ ∞∑ k= pkz + lk ∣∣∣∣∣ = ∞∑ k= pk ∣∣z+lk∣∣ = ∞∑ k= pk ∣∣z−lk∣∣ > ∣∣∣∣∣ ∞∑ k= pkz − lk ∣∣∣∣∣ , that is, the weak see arises. presence of the strategic environment effect can be seen also in the logistic version of the level-k model. figure shows the relationship between mean |x− | for bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } for four values of λ for the logistic level-k model (llk). level- and level- players in llk and lch models follow the identical behavioral rules. for level- and above, in llk, unlike in lch, level-k players assume that all the others are level k − who are making noisy choice when computing the expected payoff of choosing each integer. as we can see from the figure, when λ is large enough, we observe qualitatively the same strategic environment effect as we have seen based on lch. λ can be smaller in llk than in lch to obtain the strategic environment effect. this is because in the latter, level- is responding against the weighted average of the choices made by level- and , which is inherently noisier than the choice made by level- in llk, which responds against the choices made by level- . furthermore, the results are robust against variation in the mean level as shown by figure for three mean levels, . (left), . (middle), and . (right) for two values of λ, . (top) and . (bottom). λ = . λ = . n meanÈx- È n meanÈx- È λ = . λ = . n meanÈx- È n meanÈx- È figure : mean |x− | in bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } in llk for four values of λ. we assume mean level is . λ = . mean level = . mean level = . mean level = . n meanÈx- È n meanÈx- È n meanÈx- È λ = . mean level = . mean level = . mean level = . n meanÈx- È n meanÈx- È n meanÈx- È figure : mean |x− | in bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } in llk for three mean levels, . (left), . (middle), and . (right), and two values of λ, . (top) and . (bottom) d robustness of lch simulation results with respect to λ and the mean level figure shows the relationship under lch between the mean value of |x− | and n ∈{ , , , , , } for bcg+ (dashed blue) and bcg− (solid red) for four different values of λ, i.e. λ ∈{ . , . , . , . }, while keeping the mean level to be . . as one can see from figure , when λ = . , for lch, the difference of the mean |x − | between two bcgs is small except for n = . however, for larger values of λ, the difference in the mean |x − | between the two bcgs continues to exist for all n > . it should also be noted that the required value of λ to observe the strategic environment effect depends on the magnitude of the winning payoff. as noted in the text, in our computation, we normalized the winning payoff to be . if the winning payoff is much larger, then we would obtain the strategic environment effect with smaller values of λ. the reason for not observing the strategic environment effect when λ is small is simply because the choices for each level of agents are too noisy. figure shows the same relationship as in figure but varying the mean level. it shows the results for three mean levels, . (left), . (middle), and . (right) for two values of λ, . (top) and . (bottom). we consider these three values for the mean level following camerer et al. ( ) who report that the median estimated mean level, based on beauty contest data sets, is . . as one can easily imagine from the analysis in section , the strong strategic environment effect is driven mainly by the way level and above agents behave. thus, as the mean level declines, the difference in the mean |x− | between the two bcgs become smaller. the strategic environment effect, however, is observed even with mean level . . λ = . λ = . n meanÈx- È n meanÈx- È λ = . λ = . n meanÈx- È n meanÈx- È figure : mean |x− | in bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } in lch for four values of λ. we assume the mean level is . λ = . mean level = . mean level = . mean level = . n meanÈx- È n meanÈx- È n meanÈx- È λ = . mean level = . mean level = . mean level = . n meanÈx- È n meanÈx- È n meanÈx- È figure : mean |x− | in bcg+ (dashed blue) and bcg− (solid red) for n ∈ { , , , , , } in lch for three mean levels, . (left), . (middle), and . (right), and two values of λ, . (top) and . (bottom) e histogram of numbers chosen n= n= bcg − bcg + bcg − bcg + x . . . . . pdf x . . . . . pdf x . . . . . pdf x . . . . . pdf n= n= bcg − bcg + bcg − bcg + x . . . . . pdf x . . . . . pdf x . . . . . pdf x . . . . . pdf n= n= bcg − bcg + bcg − bcg + x . . . . . pdf x . . . . . pdf x . . . . . pdf x . . . . . pdf n= uncertain n bcg − bcg + bcguncertain− bcguncertain+ x . . . . . pdf x . . . . . pdf x . . . . . pdf x . . . . . pdf figure : histogram of numbers chosen by subjects in bcgn− and bcgn+ for various group size n. here we consider only the first game each subject played. f instructions this section of the appendix presents an english translation of the instructions used in our exper- iment with n = where bcg + was played before bcg −. the other treatments are different from the one presented in terms of the the number of players in the room and the examples shown. we have taken particular care to give isomorphic examples for all values of n. the examples shown in various treatments are summarized at the end of this section. the instructions for the uncertain group size treatment were in the same format. the main difference is the first sentence and the last paragraph of the instructions of each game. for the first sentence in the uncertain group size treatment, instead of stating “you interact with n − other randomly selected people in this room” as in the other treatments, it reads “you do not know with how many people in this room you will interact. you can interact with some of the people in this room ( , , , etc) or with all of them. ” the last paragraph in the uncertain group size treatment reads, “when everybody has made his/her choice, we will randomly choose with how many people you will interact and the choices will be randomly assembled in groups of that size, and the winners will be computed (and you will be able to take your money if you won). every group size has equal probability to be chosen.” this should be contrasted with the paragraph of the other treatments that reads “when everybody has made his/her choice, the choices will be randomly divided into groups of n and the winners will be determined (and you will be able to take your money if you won).” the examples used in the instructions of the uncertain group size treatment are the same as in the n = treatment. general rule this is an experiment about decision making. you will play two games. instructions for the second game will be given to you after you finish playing the first game. this experiment allows you to earn real money. the payment rule is explained in each game. one of the two games will be randomly selected at the end of the experiment and your payments in that game will be given to you. game you interact with other randomly selected people in this room. you have to choose an integer between and . the other people will also do the same. the rule to earn money is the following: the person choosing the number closest to his or her target will earn euros, the others will earn . if the numbers chosen by several people are equally close to their own targets, one of them will be randomly chosen to earn the euros. the target for you is defined as follows: target = + (average of the numbers chosen by the other people) example : you choose and the other people choose , , . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + [( + + )/ ] = . . - = . the lowest player with choice + [( + + )/ ] = . . - = . player with choice + [( + + )/ ]= . . - = . player with choice + [( + + )/ ]= . . - = . you win because the difference between the number you chose and your target is the lowest. when everybody has made his/her choice, the choices will be randomly divided into groups of and the winners will be determined. the result will be communicated to you after you play game (and you will be able to take your money if you won). good luck! your choice (between and ): game now you still interact with three randomly selected people in this room, but the target is different. you have to choose an integer between and . the other people will do the same. the rule to earn money is the following: the person choosing the number closest to his or her target will earn euros, the others will earn . if the numbers chosen by several people are equally close to their own targets, one of them will be randomly chosen to earn the euros. the target for you is defined as follows: target = − (average of the numbers chosen by the other people) example : you choose and the other people choose , , . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − [( + + )/ ] = . . - = . the lowest player with choice − [( + + )/ ] = . . - = . player with choice − [( + + )/ ]= . . - = . player with choice − [( + + )/ ]= . . - = . you win because the difference between the number you chose and your target is the lowest. when everybody has made his/her choice, the choices will be randomly divided into groups of and the winners will be determined (and you will be able to take your money if you won). good luck! your choice (between and ): f. examples used in other treatments bcg +: you choose and the other person chooses . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + = - = the lowest player with choice + = . . - = . bcg −: you choose and the other person chooses . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − = . . - = . the lowest player with choice − = . . - = . bcg +: you choose and the other two people both choose . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + [( + )/ ] = . . - = . the lowest player with choice + [( + )/ ]= . . - = . bcg −: you choose and the other two people both choose . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − [( + )/ ] = . . - = . the lowest player with choice − [( + )/ ]= . . - = . bcg +: you choose and the other people choose , , , and . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + [( + + + )/ ] = . . - = . the lowest player with choice + [( + + + )/ ] = . . - = . player with choice + [( + + + )/ ]= - = player with choice + [( + + + )/ ]= . . - = . bcg −: you choose and the other people choose , , , and . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − [( + + + )/ ] = . . - = . the lowest player with choice − [( + + + )/ ] = . . - = . player with choice − [( + + + )/ ]= - = player with choice − [( + + + )/ ]= . . - = . bcg +: you choose and the other people choose , , , , and . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + [( + + + + )/ ] = . . - = . the lowest player with choice + [( + + + + )/ ] = . . - = . player with choice + [( + + + + )/ ]= . . - = . player with choice + [( + + + + )/ ]= . . - = . bcg −: you choose and the other people choose , , , , and . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − [( + + + + )/ ] = . . - = . the lowest player with choice − [( + + + + )/ ] = . . - = . player with choice − [( + + + + )/ ]= . . - = . player with choice − [( + + + + )/ ]= . . - = . bcg +: you choose and all the other people choose . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + [( + + + + + + )/ ] = . . - = . the lowest player with choice + [( + + + + + + )/ ]= . . - = . bcg −: you choose and all the other people choose . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − [( + + + + + + )/ ] = . . - = . the lowest player with choice − [( + + + + + + )/ ]= . . - = . bcg +: you choose and other people choose , and the remaining have chosen . the targets and the differences to the targets are: players target difference to the target you (your choice: ) + [( × + × )/ ] = . . - = . the lowest player with choice + [( × + × + )/ ]= . . - = . player with choice + [( × + × + )/ ] = . . - = . bcg −: you choose and other people choose , and the remaining have chosen . the targets and the differences to the targets are: players target difference to the target you (your choice: ) − [( × + × )/ ] = . . - = . the lowest player with choice − [( × + × + )/ ]= . . - = . player with choice − [( × + × + )/ ] = . . - = . rainbows, halos, coronas and glories: beautiful sources of information in: bulletin of the american meteorological society volume issue ( ) jump to content jump to main navigation journals bulletin of the american meteorological society earth interactions journal of 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rainbows: seen in nature, at long last. atmospheric halos and their information content. diffraction coronas and glories, and their information content. diffraction coronas. glories. postscript. references export references .ris procite refworks reference manager .bib bibtex zotero .enw endnote boyer, c. b., : the rainbow: from myth to mathematics. princeton university press, pp. brandes, h. w., : venturi’s theorie des farbigen bogens, welcher sich oft an der innern seite des regenboges zeigt, dargestellt mit einigen anmerkungen. ann. phys., , – , doi: . /andp. . crossref brandes, h. w., : venturi’s theorie des farbigen bogens, welcher sich oft an der innern seite des regenboges zeigt, dargestellt mit einigen anmerkungen. ann. phys., , – , doi: . /andp. . . /andp. )| false search google scholar export citation corliss, w. r., : handbook of unusual natural phenomena. sourcebook project, pp. edens, h. e., : photographic observation of a natural fifth-order rainbow. appl. opt., , b –b , doi: . /ao. . b . crossref edens, h. e., : photographic observation of a natural fifth-order rainbow. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation edens, h. e., and g. p. können, : probable photographic detection of the natural seventh-order rainbow. appl. opt., , b –b , doi: . /ao. . b . crossref edens, h. e., and g. p. können, : probable photographic detection of the natural seventh-order rainbow. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation evans, l., : remarkable lunar halo. quart. j. roy. meteor. soc., , , doi: . /qj. . evans, l., : remarkable lunar halo. quart. j. roy. meteor. soc., , , doi: . /qj. .)| false search google scholar export citation floor, c., : glory from space. weather, , , doi: . /wea. . crossref floor, c., : glory from space. weather, , , doi: . /wea. . . /wea. )| false search google scholar export citation fraser, a. b., : why can the supernumerary bows be seen in a rain shower? j. opt. soc. amer., , – , doi: . /josa. . . crossref fraser, a. b., : why can the supernumerary bows be seen in a rain shower? j. opt. soc. amer., , – , doi: . /josa. . . . /josa. . )| false search google scholar export citation greenler, r., : rainbows, halos, and glories. cambridge university press, pp. großmann, m., e. schmidt, and a. haußmann, : photographic evidence for the third-order rainbow. appl. opt., , f –f , doi: . /ao. . f . crossref großmann, m., e. schmidt, and a. haußmann, : photographic evidence for the third-order rainbow. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation hansen, j. e., and j. hovenier, : interpretation of the polarization of venus. j. atmos. sci., , – , doi: . / - ( ) < :iotpov> . .co; . crossref hansen, j. e., and j. hovenier, : interpretation of the polarization of venus. j. atmos. sci., , – , doi: . / - ( ) < :iotpov> . .co; . . / - ( ) < :iotpov> . .co; )| false search google scholar export citation haußmann, a., : observation, analysis, and reconstruction of a twinned rainbow. appl. opt., , b –b , doi: . /ao. . b . crossref haußmann, a., : observation, analysis, and reconstruction of a twinned rainbow. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation israelevich, p. l., j. h. joseph, z. levin, and y. yair, : first observation of glory from space. bull. amer. meteor. soc., , – , doi: . / bams . . crossref israelevich, p. l., j. h. joseph, z. levin, and y. yair, : first observation of glory from space. bull. amer. meteor. soc., , – , doi: . / bams . . . / bams . )| false search google scholar export citation karalidi, t., d. m. stam, and j. w. hovenier, : looking for the rainbow on exoplanets covered by liquid and icy water clouds. astron. astrophys., , a , doi: . / - / . crossref karalidi, t., d. m. stam, and j. w. hovenier, : looking for the rainbow on exoplanets covered by liquid and icy water clouds. astron. astrophys., , a , doi: . / - / . . / - / )| false search google scholar export citation können, g. p., : polarized light in nature. cambridge university press, pp. können, g. p., : appearance of supernumeraries of the secondary rainbow in rain showers. j. opt. soc. amer., a, – , doi: . /josaa. . . crossref können, g. p., : appearance of supernumeraries of the secondary rainbow in rain showers. j. opt. soc. amer., a, – , doi: . /josaa. . . . /josaa. . )| false search google scholar export citation können, g. p., : titan halos. titan, from discovery to encounter, k. fletcher, ed., esa sp- , – . können, g. p., : a halo on mars. weather, , – , doi: . /wea. . . crossref können, g. p., : a halo on mars. weather, , – , doi: . /wea. . . . /wea. . )| false search google scholar export citation laven, p., a: atmospheric glories: simulations and observations. appl. opt., , – , doi: . /ao. . . crossref laven, p., a: atmospheric glories: simulations and observations. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation laven, p., b: how are glories formed? appl. opt., , – , doi: . /ao. . . crossref laven, p., b: how are glories formed? appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation laven, p., a: effects of refractive index on glories. appl. opt., , h –h , doi: . /ao. . h . crossref laven, p., a: effects of refractive index on glories. appl. opt., , h –h , doi: . /ao. . h . . /ao. . h )| false search google scholar export citation laven, p., b: noncircular glories and their relationship to cloud droplet size. appl. opt., , h –h , doi: . /ao. . h . crossref laven, p., b: noncircular glories and their relationship to cloud droplet size. appl. opt., , h –h , doi: . /ao. . h . . /ao. . h )| false search google scholar export citation laven, p., : re-visiting the atmospheric corona. appl. opt., , b –b , doi: . /ao. . b . crossref laven, p., : re-visiting the atmospheric corona. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation lee, r. l., and p. laven, : visibility of natural tertiary rainbows. appl. opt., , f –f , doi: . /ao. . f . crossref lee, r. l., and p. laven, : visibility of natural tertiary rainbows. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation lefaudeux, n. a., : crystals of hexagonal ice with ( - ) miller index faces explain exotic arcs in the lascar halo display. appl. opt., , f –f , doi: . /ao. . f . crossref lefaudeux, n. a., : crystals of hexagonal ice with ( - ) miller index faces explain exotic arcs in the lascar halo display. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation markiewicz, w. j., and coauthors, : glory on venus cloud tops and the unknown uv absorber. icarus, , – , doi: . /j.icarus. . . . crossref markiewicz, w. j., and coauthors, : glory on venus cloud tops and the unknown uv absorber. icarus, , – , doi: . /j.icarus. . . . . /j.icarus. . . )| false search google scholar export citation minnaert, m. g. m., : light and color in the outdoors. springer-verlag, pp. crossref minnaert, m. g. m., : light and color in the outdoors. springer-verlag, pp. . / - - - - )| false export citation möbius, w., : zur theorie des regenbogens und ihrer experimentellen prüfung. ann. phys., , – , doi: . /andp. . crossref möbius, w., : zur theorie des regenbogens und ihrer experimentellen prüfung. ann. phys., , – , doi: . /andp. . . /andp. )| false search google scholar export citation parviainen, p., c. f. bohren, and v. mäkelä, : vertical elliptical coronas caused by pollen. appl. opt., , – , doi: . /ao. . . crossref parviainen, p., c. f. bohren, and v. mäkelä, : vertical elliptical coronas caused by pollen. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation petrova, e. v., s. oksana, w. j. shalygina, and w. j. markiewicz, : the vmc/vex photometry at small phase angles: glory and the physical properties of particles in the upper cloud layer of venus. planet. space sci., – , – , doi: . /j.pss. . . . crossref petrova, e. v., s. oksana, w. j. shalygina, and w. j. markiewicz, : the vmc/vex photometry at small phase angles: glory and the physical properties of particles in the upper cloud layer of venus. planet. space sci., – , – , doi: . /j.pss. . . . . /j.pss. . . )| false search google scholar export citation riikonen, m., m. sillanpää, l. virta, d. sullivan, j. moilanen, and i. luukkonen, : halo observations provide evidence of airborne cubic ice in the earth’s atmosphere. appl. opt., , – , doi: . /ao. . . crossref riikonen, m., m. sillanpää, l. virta, d. sullivan, j. moilanen, and i. luukkonen, : halo observations provide evidence of airborne cubic ice in the earth’s atmosphere. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation shaw, j. a., r. l. lee, and p. laven, : light and color in the open air: introduction to the feature issue. appl. opt., , lc –lc , doi: . /ao. . lc . crossref shaw, j. a., r. l. lee, and p. laven, : light and color in the open air: introduction to the feature issue. appl. opt., , lc –lc , doi: . /ao. . lc . . /ao. . lc )| false search google scholar export citation tape, w., : atmospheric halos. antarctic research series, vol. , amer. geophys. union, pp. crossref tape, w., : atmospheric halos. antarctic research series, vol. , amer. geophys. union, pp. . /ar )| false export citation tape, w., and j. moilanen, : atmospheric halos and the search for angle x. amer. geophys. union, pp., doi: . /sp . crossref tape, w., and j. moilanen, : atmospheric halos and the search for angle x. amer. geophys. union, pp., doi: . /sp . . /sp )| false export citation theusner, m., : photographic observation of a natural fourth-order rainbow. appl. opt., , f –f , doi: . /ao. . f . crossref theusner, m., : photographic observation of a natural fourth-order rainbow. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation tomasko, m. g., and coauthors, : rain, winds and haze during the huygens probe’s descent to titan’s surface. nature, , – , doi: . /nature . crossref tomasko, m. g., and coauthors, : rain, winds and haze during the huygens probe’s descent to titan’s surface. nature, , – , doi: . /nature . . /nature )| false search google scholar export citation tränkle, e., and b. mielke, : simulation and analysis of pollen coronas. appl. opt., , – , doi: . /ao. . . crossref tränkle, e., and b. mielke, : simulation and analysis of pollen coronas. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation van de hulst, h. c., : a theory of the anti-coronae. j. opt. soc. amer., , – , doi: . /josa. . . crossref van de hulst, h. c., : a theory of the anti-coronae. j. opt. soc. amer., , – , doi: . /josa. . . . /josa. . )| false search google scholar export citation venturi, g. b., : commentari sopra la storia e la teorie dell’ottica. pe’ fratelly masi, pp. [available online at www.e-rara.ch/zut/content/titleinfo/ .] figures export figures view in gallery detail of a secondary rainbow over brannenburg, germany. see fig. for the full image. view in gallery primary and secondary rainbows in a rain shower over new mexico (nm). the color sequence of the bows is reversed; the sky is darkest between the bows. the reversed colors of the secondary rainbow arise because the emerging light rays cross the incoming light rays. because of the flattened shape of the falling drops, the primary rainbow is slightly flattened in heavy showers. the diagrams (labeled and ) indicate the ray paths through the drop that form the primary and secondary rainbows. photograph taken by h. e. edens in magdalena, nm, at utc sep . solar elevation is . °. view in gallery the rainbow in freshwater raindrops is extended below the horizon by a rainbow in seawater spray. the slightly larger refractive index of saltwater drops causes the radius of the subhorizon rainbow to be . ° less than that of the above-horizon freshwater rainbow. photograph taken by j. dijkema in the pacific ocean, km southeast of japan, during . solar elevation is . °. view in gallery primary rainbow with two interference bows along its inner side (the supernumerary bows). an incorrect conclusion may be drawn from the spacing between the interference bows if the rainbow appears in a heavy shower. their spacing does relate to the size of the rainbow-generating drops, but in the case of a broad drop size distribution (such as in the case of heavy showers), the size of the rainbow-generating drops is not related to the mean drop size in the shower. photograph taken by c. hinz in brannenburg, germany, at utc aug . solar elevation is . °. view in gallery first picture ever of the fourth rainbow and second picture ever of the third rainbow. this pair of high-order rainbows appears on the sun side of the sky and is made visible by contrast enhancement; the foreground landscape is not contrast enhanced. as in the case of the primary and secondary rainbows, the third and fourth rainbows have their red sides toward each other. however, the spacing between them is decreased. the diagrams (labeled and ) indicate the ray paths through the drop that form the third and fourth rainbows. photograph taken by m. theusner in schiffdorf, germany, at utc jun . solar elevation is . °. view in gallery first picture ever of the fifth rainbow. the green and blue hues between the primary and secondary rainbows are from the (broad) fifth rainbow whose red component is hidden by the much brighter secondary rainbow. the picture is contrast enhanced. the diagrams (labeled , , and ) indicate the ray paths through the drop that form the primary, secondary, and fifth rainbows. photograph taken by h. e. edens at langmuir laboratory, nm, at utc aug . solar elevation is . °. view in gallery complex halo display due to simple ice crystals. this rich halo display is due to simple hexagonal ice crystals with flat ends, floating in various modes of orientation. the two circular halos are due to crystals having random orientations and have radii of ° and °, respectively. associated with these circular halos are arcs caused by the same crystals in the swarm, but now preferentially oriented. the spots to the right and left of the sun are the ° parhelia (“sundogs”). the names of the many other halo arcs can be found in tape ( ). the sixfold symmetry in the arrangement of the arcs associated with the ° halo is an expression of the sixfold symmetry of the ice crystals causing the display. the sun is hidden behind a nearby object. this display is outstanding; more frequent mediocre displays are bleaker and usually lack the ° features. photograph taken by g. p. können at u.s. amundsen–scott south pole station ( °s) at utc jan . solar elevation is . °. the horizontal field of view is °. view in gallery complex halo display due to exotic ice crystals. this halo display is caused by hexagonal ice crystals having pyramidal rather than flat ends. the presence of these crystals manifests itself by the appearance of multiple circular halos with radii between ° and °, the vanishing of most of the ° and ° features in fig. , and the appearance of strange-shaped halo arcs at unusual places. the sun is hidden behind a nearby object. this stacked picture is contrast enhanced. photograph taken by m. riikonen at oulu, finland, around noon on sep . solar elevation is °. the horizontal field of view is °. view in gallery (left) halo in the terrestrial atmosphere. (right) halo in the thin clouds of mars. the white streak in the pictures is the so-called subsun, a halo that appears as an elongated mirror image of the sun in the clouds. it is due to the reflection of sunlight by horizontally oriented crystal faces; see the diagram in the left panel. the picture of the terrestrial subsun is taken from an aircraft; its length (∼ °) indicates a mean tilt angle of ° of the reflecting crystal faces. the mars picture is taken by a scanning platform, causing the martian subsun to be strongly elongated. left photograph taken by m. vollmer on a flight from fairbanks, ak, to frankfurt, germany, at utc aug . solar elevation is ∼ °. the horizontal field of view is °. right photograph taken on jan by the national aeronautics and space administration/jet propulsion laboratory/malin space science systems (nasa/jpl/msss) mars orbiter camera (moc – ), covering an area of km × km on mars. view in gallery typical diffraction corona around a gibbous moon, during morning twilight. in the naïve and widely applied approach, the angular diameter of the red ring, about . °, which surrounds the white aureole, indicates a particle size of μm. this turns out to be an overestimation by almost a factor of . photograph taken by c. hinz from the mountain wendelstein ( m) in the bavarian alps at utc, min before sunrise, on jan . solar elevation is − . °. the horizontal field of view is °. view in gallery typical appearance of a glory as seen from an aircraft. the glory is centered on the shadow of the plane or, better, on the shadow of the camera that took this picture. the distance of the glory’s center below the horizon indicates a solar elevation of . °. the angular diameter of the glory’s inner red ring of about ° indicates a drop diameter of about μm. photograph taken by p. laven at utc mar , shortly after takeoff on a flight from geneva, switzerland, to london, united kingdom. the horizontal field of view is °. view in gallery deformed glory on a cap cloud over the top of a neighboring mountain. the gradients in droplet size cause the formation of a colored sideward extension on the right-hand side of the glory. a detailed analysis reveals drop diameters ranging from about μm in the undisturbed part down to μm in the colored extension (laven b). the picture is contrast enhanced. photograph taken by c. hinz from the mountain wendelstein ( m) in the bavarian alps at utc nov . solar elevation is . °. the horizontal field of view is °. view in gallery glory observed from space. the angular diameter of the glory of about ° corresponds to a drop diameter of about μm (laven a). photograph taken above the atlantic by the israeli astronaut i. ramon, on board the ill-fated space shuttle columbia, at : utc jan , days before the crash. the glory’s center is at . °s, . °w, km southwest of liberia. the horizontal field of view of . ° covers km on earth’s surface. the arrow indicates north. (image reproduced with permission of p. israelevich, tel aviv university, tel aviv, israel.) close view raw image detail of a secondary rainbow over brannenburg, germany. see fig. for the full image. view raw image primary and secondary rainbows in a rain shower over new mexico (nm). the color sequence of the bows is reversed; the sky is darkest between the bows. the reversed colors of the secondary rainbow arise because the emerging light rays cross the incoming light rays. because of the flattened shape of the falling drops, the primary rainbow is slightly flattened in heavy showers. the diagrams (labeled and ) indicate the ray paths through the drop that form the primary and secondary rainbows. photograph taken by h. e. edens in magdalena, nm, at utc sep . solar elevation is . °. view raw image the rainbow in freshwater raindrops is extended below the horizon by a rainbow in seawater spray. the slightly larger refractive index of saltwater drops causes the radius of the subhorizon rainbow to be . ° less than that of the above-horizon freshwater rainbow. photograph taken by j. dijkema in the pacific ocean, km southeast of japan, during . solar elevation is . °. view raw image primary rainbow with two interference bows along its inner side (the supernumerary bows). an incorrect conclusion may be drawn from the spacing between the interference bows if the rainbow appears in a heavy shower. their spacing does relate to the size of the rainbow-generating drops, but in the case of a broad drop size distribution (such as in the case of heavy showers), the size of the rainbow-generating drops is not related to the mean drop size in the shower. photograph taken by c. hinz in brannenburg, germany, at utc aug . solar elevation is . °. view raw image first picture ever of the fourth rainbow and second picture ever of the third rainbow. this pair of high-order rainbows appears on the sun side of the sky and is made visible by contrast enhancement; the foreground landscape is not contrast enhanced. as in the case of the primary and secondary rainbows, the third and fourth rainbows have their red sides toward each other. however, the spacing between them is decreased. the diagrams (labeled and ) indicate the ray paths through the drop that form the third and fourth rainbows. photograph taken by m. theusner in schiffdorf, germany, at utc jun . solar elevation is . °. view raw image first picture ever of the fifth rainbow. the green and blue hues between the primary and secondary rainbows are from the (broad) fifth rainbow whose red component is hidden by the much brighter secondary rainbow. the picture is contrast enhanced. the diagrams (labeled , , and ) indicate the ray paths through the drop that form the primary, secondary, and fifth rainbows. photograph taken by h. e. edens at langmuir laboratory, nm, at utc aug . solar elevation is . °. view raw image complex halo display due to simple ice crystals. this rich halo display is due to simple hexagonal ice crystals with flat ends, floating in various modes of orientation. the two circular halos are due to crystals having random orientations and have radii of ° and °, respectively. associated with these circular halos are arcs caused by the same crystals in the swarm, but now preferentially oriented. the spots to the right and left of the sun are the ° parhelia (“sundogs”). the names of the many other halo arcs can be found in tape ( ). the sixfold symmetry in the arrangement of the arcs associated with the ° halo is an expression of the sixfold symmetry of the ice crystals causing the display. the sun is hidden behind a nearby object. this display is outstanding; more frequent mediocre displays are bleaker and usually lack the ° features. photograph taken by g. p. können at u.s. amundsen–scott south pole station ( °s) at utc jan . solar elevation is . °. the horizontal field of view is °. view raw image complex halo display due to exotic ice crystals. this halo display is caused by hexagonal ice crystals having pyramidal rather than flat ends. the presence of these crystals manifests itself by the appearance of multiple circular halos with radii between ° and °, the vanishing of most of the ° and ° features in fig. , and the appearance of strange-shaped halo arcs at unusual places. the sun is hidden behind a nearby object. this stacked picture is contrast enhanced. photograph taken by m. riikonen at oulu, finland, around noon on sep . solar elevation is °. the horizontal field of view is °. view raw image (left) halo in the terrestrial atmosphere. (right) halo in the thin clouds of mars. the white streak in the pictures is the so-called subsun, a halo that appears as an elongated mirror image of the sun in the clouds. it is due to the reflection of sunlight by horizontally oriented crystal faces; see the diagram in the left panel. the picture of the terrestrial subsun is taken from an aircraft; its length (∼ °) indicates a mean tilt angle of ° of the reflecting crystal faces. the mars picture is taken by a scanning platform, causing the martian subsun to be strongly elongated. left photograph taken by m. vollmer on a flight from fairbanks, ak, to frankfurt, germany, at utc aug . solar elevation is ∼ °. the horizontal field of view is °. right photograph taken on jan by the national aeronautics and space administration/jet propulsion laboratory/malin space science systems (nasa/jpl/msss) mars orbiter camera (moc – ), covering an area of km × km on mars. view raw image typical diffraction corona around a gibbous moon, during morning twilight. in the naïve and widely applied approach, the angular diameter of the red ring, about . °, which surrounds the white aureole, indicates a particle size of μm. this turns out to be an overestimation by almost a factor of . photograph taken by c. hinz from the mountain wendelstein ( m) in the bavarian alps at utc, min before sunrise, on jan . solar elevation is − . °. the horizontal field of view is °. view raw image typical appearance of a glory as seen from an aircraft. the glory is centered on the shadow of the plane or, better, on the shadow of the camera that took this picture. the distance of the glory’s center below the horizon indicates a solar elevation of . °. the angular diameter of the glory’s inner red ring of about ° indicates a drop diameter of about μm. photograph taken by p. laven at utc mar , shortly after takeoff on a flight from geneva, switzerland, to london, united kingdom. the horizontal field of view is °. view raw image deformed glory on a cap cloud over the top of a neighboring mountain. the gradients in droplet size cause the formation of a colored sideward extension on the right-hand side of the glory. a detailed analysis reveals drop diameters ranging from about μm in the undisturbed part down to μm in the colored extension (laven b). the picture is contrast enhanced. photograph taken by c. hinz from the mountain wendelstein ( m) in the bavarian alps at utc nov . solar elevation is . °. the horizontal field of view is °. view raw image glory observed from space. the angular diameter of the glory of about ° corresponds to a drop diameter of about μm (laven a). photograph taken above the atlantic by the israeli astronaut i. ramon, on board the ill-fated space shuttle columbia, at : utc jan , days before the crash. the glory’s center is at . °s, . °w, km southwest of liberia. the horizontal field of view of . ° covers km on earth’s surface. the arrow indicates north. (image reproduced with permission of p. israelevich, tel aviv university, tel aviv, israel.) cited by metrics all time past year past days abstract views full text views pdf downloads related content chart i. tracks of centers of anticyclones, december, . (inset) departure of monthly mean pressure from normal meteorological summary for january, , in south america meteorological summary for southern south america, february, author: seÑor j. b. navarrete recent papers bearing on meteorology and seismology new orleans forecast district previous article next article editorial type: article rainbows, halos, coronas and glories: beautiful sources of information gunther p. können view more view less royal netherlands meteorological institute, de bilt, netherlands print publication: mar doi: https://doi.org/ . /bams-d- - . page(s): – article history final form: aug published online: mar download pdf © get permissions full access abstract/excerpt full text pdf abstract rainbows, halos, coronas, and glories are aesthetic features admired over millennia by man. they are also carriers of useful information about the physical properties of drops and solid particles floating in the atmospheres of earth and other planets. although atmospheric optics is a centuries-old discipline, significant progress in the understanding of these phenomena has been achieved during the past years, as well as of their relation to the physical properties of the individual scatterers. at the same time, with the development of planetary exploration, the number of observations of rainbows, halos, and glories in the atmospheres of planets other than earth is steadily growing. in this article we describe these phenomena and their information content and illustrate them with pictures mostly showing their typical appearance rather than presenting the “best pictures ever.” * retired © american meteorological society. for information regarding reuse of this content and general copyright information, consult the ams copyright policy (www.ametsoc.org/pubsreuselicenses). corresponding author e-mail: gunther p. können, konnen@planet.nl abstract rainbows, halos, coronas, and glories are aesthetic features admired over millennia by man. they are also carriers of useful information about the physical properties of drops and solid particles floating in the atmospheres of earth and other planets. although atmospheric optics is a centuries-old discipline, significant progress in the understanding of these phenomena has been achieved during the past years, as well as of their relation to the physical properties of the individual scatterers. at the same time, with the development of planetary exploration, the number of observations of rainbows, halos, and glories in the atmospheres of planets other than earth is steadily growing. in this article we describe these phenomena and their information content and illustrate them with pictures mostly showing their typical appearance rather than presenting the “best pictures ever.” * retired © american meteorological society. for information regarding reuse of this content and general copyright information, consult the ams copyright policy (www.ametsoc.org/pubsreuselicenses). corresponding author e-mail: gunther p. können, konnen@planet.nl the study of rainbowlike features has seen a revival—relationships with properties of the scattering particles have been revisited, and the number of observations in other planetary atmospheres has increased. download figure download figure as powerpoint slide detail of a secondary rainbow over brannenburg, germany. see fig. for the full image. citation: bulletin of the american meteorological society , ; . /bams-d- - . if regularly shaped transparent particles of sufficient size are present in the atmosphere and if they are lit by the sun, colored structures may appear at specific locations on the celestial sphere. the best known among these structures is the primary rainbow, which appears in sunlit raindrops as a colored circular segment of radius °, centered on one’s shadow point (also called the antisolar point). almost equally well known is the lunar diffraction corona in its most basic form: a reddish circle a few degrees wide that surrounds the moon. less known though more common than rainbows are halos, which appear in sunlit ice crystals and are chiefly located on the sun side of the celestial sphere. even lesser known is the glory, which appears as a “minirainbow” around one’s shadow when the shadow is cast on water clouds or fog. in past times it was rarely seen, but nowadays it is frequently seen by observant air travelers. the opening statements of this article can equally well be formulated the other way around: if a halo or rainbow is observed in the sky, information is available about the shapes, sizes, and/or composition of airborne particles. each phenomenon carries its own specific information about the particles that generate it. this information is sometimes difficult to obtain from other sources. the appearance of most of these phenomena is transient and occurs at unpredictable times. but in cases where the actual state of the atmosphere at a certain moment is of importance, or when one is interested in knowing the composition of particles floating in the air, their observation may help. this paper describes the appearance and peculiarities of these four phenomena, the information they contain, new insights that have been gained during the past years, and cases where they have been observed from space in the atmospheres of planets. rainbows and their information content. “normal” rainbows and their super-numeraries. the chief characteristic of a rainbow is its roundness, which is a direct consequence of the sphericity of drops. so the presence of a rainbow tells us that there are spherical particles present in the sky: water drops, of course. when a drop is flattened, its primary rainbow is flattened as well (venturi ; brandes ; möbius ). large falling drops are flattened by aerodynamic forces and as a result so is the rainbow in heavy showers. for a low-sun rainbow, its distance to the antisolar point is about ° smaller at its top than at its sides (fraser ; haußmann ). the primary rainbow is generated by a light path through a drop that consists of entry–reflection–exit. an additional internal reflection creates another rainbow, called the secondary rainbow. that rainbow appears a few degrees outside the primary one and is recognizable by its reversed color sequence (fig. ). the °-wide region between the two rainbows is the darkest part of the sky. the secondary rainbow always accompanies the -times-brighter primary one, but because of its intrinsic dimness it often remains unnoticed. fig. . download figure download figure as powerpoint slide primary and secondary rainbows in a rain shower over new mexico (nm). the color sequence of the bows is reversed; the sky is darkest between the bows. the reversed colors of the secondary rainbow arise because the emerging light rays cross the incoming light rays. because of the flattened shape of the falling drops, the primary rainbow is slightly flattened in heavy showers. the diagrams (labeled and ) indicate the ray paths through the drop that form the primary and secondary rainbows. photograph taken by h. e. edens in magdalena, nm, at utc sep . solar elevation is . °. citation: bulletin of the american meteorological society , ; . /bams-d- - . the primary and secondary rainbows contain much the same physical information. a difference is that the secondary rainbow is always perfect circular, as its position in the sky is insensitive to the flattening that occurs for large falling drops (können ). thus, in contrast to the primary rainbow, the position of the top of the secondary rainbow contains no information about the nonsphericity of falling drops. the internal reflections in the rainbow-making light paths through the drops happen to occur so close to the brewster angle that rainbows are almost entirely polarized, which can be easily checked using a simple polarizer. if an isolated colored spot appears in the sky, rotating a polarizer in front of the eye can confirm whether the spot is a segment of a rainbow: when it disappears at a certain orientation of the polarizer, the identification is positive, and it is confirmed that the scatterers are drops. the rainbow polarization is so strong that weak rainbows are more easily detected by their polarization rather than by their intensity. this is particularly useful if one tries to detect rainbows due to drops of sizes in the -µm range and below, where the rainbow has lost its brilliance and has turned into a colorless white band. such drops are usually the constituents of altocumulus clouds. if sunlit, they produce a white rainbow at ∼ ° from the shadow point, but this inconspicuous bow is often lost in the chaotic structure of the cloud elements. however, with a polarizer the rainbow component in the cloud’s radiance appears clearly. in this way, rainbows can be seen on almost every partly cloudy day, albeit only with a polarizer (können ). the rainbow angle depends on the refractive index and hence on the chemical composition of the drops. seawater, having a higher refractive index than freshwater, shifts the rainbow in the direction of the antisolar point. scrutinizing the rainbow shift in fig. as a function of wavelength could reveal that seawater contains salt (nacl). obviously, there exists a more direct method to find out that seawater is salty. but for planets other than earth it is not so easy. in the early s hansen and hovenier ( ) recognized a prominent rainbow peak in the polarization of venus and analyzed its properties and its shift relative to a freshwater rainbow. from this they concluded that the venus upper clouds consist of drops with sizes on the order of microns, and that these drops would taste somewhat sour rather than salty because they very likely consist of concentrated sulfuric acid. in the late s this conclusion was beautifully confirmed by in situ measurements of descending space probes. fig. . download figure download figure as powerpoint slide the rainbow in freshwater raindrops is extended below the horizon by a rainbow in seawater spray. the slightly larger refractive index of saltwater drops causes the radius of the subhorizon rainbow to be . ° less than that of the above-horizon freshwater rainbow. photograph taken by j. dijkema in the pacific ocean, km southeast of japan, during . solar elevation is . °. citation: bulletin of the american meteorological society , ; . /bams-d- - . not every rainbow feature offers the information it suggests. a deceptive example comes from the narrow bows visible close to the inside of the primary rainbow, called the supernumerary bows (fig. ), which are caused by the interference of rays inside the droplet. the obvious explanation is that the spacing between the bows relates to the droplet size in rain. for a peaked drop size distribution this is indeed the case, but for a broad and flat drop size distribution, as occurs in heavy showers, it is not. in fact, because of smearing one would expect no interference fringes at all. as pointed out by fraser ( ), supernumeraries nevertheless arise in this case because of the shift of the rainbow angle as a result of the flattening of falling drops. this causes a selection effect that for any broad drop size distribution produces supernumeraries with mutual spacing of about . ° (corresponding to a drop diameter of . mm), but the spacing between these interference bows does not contain any useful information about the range of drop sizes in the shower. fig. . download figure download figure as powerpoint slide primary rainbow with two interference bows along its inner side (the supernumerary bows). an incorrect conclusion may be drawn from the spacing between the interference bows if the rainbow appears in a heavy shower. their spacing does relate to the size of the rainbow-generating drops, but in the case of a broad drop size distribution (such as in the case of heavy showers), the size of the rainbow-generating drops is not related to the mean drop size in the shower. photograph taken by c. hinz in brannenburg, germany, at utc aug . solar elevation is . °. citation: bulletin of the american meteorological society , ; . /bams-d- - . high-order rainbows: seen in nature, at long last. light that has undergone three internal reflections during its path though a drop makes a third rainbow, four reflections a fourth rainbow, and so on. these “high-order rainbows” become increasingly weaker. just like the primary and secondary rainbows, the third and fourth rainbows are close together (separated by about °) and have their red sides facing each other. however, this duo appears on the bright side of the sky, ° from the sun. the fifth rainbow is located in the region opposite the sun again, not far from the primary and secondary rainbows. although there are no a priori reasons that prevent the observation of the third rainbow in nature, it was only recently that it was unambiguously detected. before it was searched for in the wrong part of the sky (boyer ), and since then only a handful of possible sightings of the third rainbow have been reported, most of them being of dubious quality (lee and laven ). this changed dramatically in when großmann ( ), inspired by the above study by lee and laven, decided to take “in the blind” pictures in the correct direction, and after some image processing, the long-searched-for third rainbow was found! one month later, in an attempt to reproduce this successful observation, theusner ( ) obtained a picture containing both the third and fourth rainbows. in edens ( ) photographed the fifth, and in he found traces in his earlier pictures of what could be the seventh rainbow (edens and können ). since then, more pictures of high-order rainbows have become known. figure shows the iconic picture of the third and fourth rainbows by theusner; fig. shows the discovery picture with the green and blue hues of the fifth rainbow—its red being hidden behind the much brighter secondary rainbow. fig. . download figure download figure as powerpoint slide first picture ever of the fourth rainbow and second picture ever of the third rainbow. this pair of high-order rainbows appears on the sun side of the sky and is made visible by contrast enhancement; the foreground landscape is not contrast enhanced. as in the case of the primary and secondary rainbows, the third and fourth rainbows have their red sides toward each other. however, the spacing between them is decreased. the diagrams (labeled and ) indicate the ray paths through the drop that form the third and fourth rainbows. photograph taken by m. theusner in schiffdorf, germany, at utc jun . solar elevation is . °. citation: bulletin of the american meteorological society , ; . /bams-d- - . fig. . download figure download figure as powerpoint slide first picture ever of the fifth rainbow. the green and blue hues between the primary and secondary rainbows are from the (broad) fifth rainbow whose red component is hidden by the much brighter secondary rainbow. the picture is contrast enhanced. the diagrams (labeled , , and ) indicate the ray paths through the drop that form the primary, secondary, and fifth rainbows. photograph taken by h. e. edens at langmuir laboratory, nm, at utc aug . solar elevation is . °. citation: bulletin of the american meteorological society , ; . /bams-d- - . atmospheric halos and their information content. halos not only exist in the form of colored circles around the sun, but can also appear as arcs, spots, streaks, loops, and circles at various locations of the celestial sphere, a consequence of the faceted nature of crystals. simple isolated halos occur frequently in the sky: in the midlatitudes, a well-trained observer may see a halo or a trace of it typically five to seven times per month (minnaert ), but for others often halos remain unnoticed because of their proximity to the sun. sunglasses help to improve one’s observational record. the presence of halos indicates that polyhedral solid particles are present in the atmosphere, namely ice crystals. any pair of crystal faces may act as a refracting prism, generating colored phenomena concentrated on the sun side of the sky. if the crystals are randomly oriented, the halos appear as concentric circles centered on the sun, with radii depending on the refractive index and the angle between the refracting faces. however, usually many of the halo-making crystals assume a preferential orientation in the air, which results in the appearance of a large variety of colored or white halo structures—many of them being positioned near the circular halo to which they are associated and others occurring at other locations on the celestial sphere (greenler ; tape ; tape and moilanen ). mostly, halo-making ice crystals are hexagonal plates or columns with flat ends. the two possible refracting prisms in these simple crystals have interfacial angles of ° and °, giving rise to halos grouped at ° and ° from the sun, respectively. figure shows a well-developed halo display with circular halos as well as halo arcs. the arrangement of the halo arcs around the circular halos is not random but represents a mapping of the crystal symmetry onto the celestial sphere; for example, the sixfold symmetry in the arrangement of the arcs associated with the ° circular halo in fig. is an expression of the sixfold symmetry of ice crystals. sometimes terrestrial halos originate from ice crystals with pyramidal instead of flat faces at their ends (tape and moilanen ; tape and references therein), which results in a different and often more complicated halo display (fig. ). to many people, the shapes of crystals bear a certain beauty. great halo displays are celestial manifestations of this crystalline beauty. fig. . download figure download figure as powerpoint slide complex halo display due to simple ice crystals. this rich halo display is due to simple hexagonal ice crystals with flat ends, floating in various modes of orientation. the two circular halos are due to crystals having random orientations and have radii of ° and °, respectively. associated with these circular halos are arcs caused by the same crystals in the swarm, but now preferentially oriented. the spots to the right and left of the sun are the ° parhelia (“sundogs”). the names of the many other halo arcs can be found in tape ( ). the sixfold symmetry in the arrangement of the arcs associated with the ° halo is an expression of the sixfold symmetry of the ice crystals causing the display. the sun is hidden behind a nearby object. this display is outstanding; more frequent mediocre displays are bleaker and usually lack the ° features. photograph taken by g. p. können at u.s. amundsen–scott south pole station ( °s) at utc jan . solar elevation is . °. the horizontal field of view is °. citation: bulletin of the american meteorological society , ; . /bams-d- - . fig. . download figure download figure as powerpoint slide complex halo display due to exotic ice crystals. this halo display is caused by hexagonal ice crystals having pyramidal rather than flat ends. the presence of these crystals manifests itself by the appearance of multiple circular halos with radii between ° and °, the vanishing of most of the ° and ° features in fig. , and the appearance of strange-shaped halo arcs at unusual places. the sun is hidden behind a nearby object. this stacked picture is contrast enhanced. photograph taken by m. riikonen at oulu, finland, around noon on sep . solar elevation is °. the horizontal field of view is °. citation: bulletin of the american meteorological society , ; . /bams-d- - . halos contain information about the interfacial angles within a crystal, the refractive index and hence the chemical composition of the solid, the crystal symmetry, the shape of the crystals, and the orientation that falling crystals assume in the air. from the features appearing in a halo display a model of the halo-making crystals can be constructed. the richer the halo display, the more unique is the reconstruction. although the terrestrial halo makers are nowadays well understood, surprises sometime occur. in the appearance of an atypical halo display (riikonen et al. ) proved the presence in the atmosphere of preferentially oriented ice crystals with exotic pyramidal faces—a type of ice crystal that had not been detected before in the free atmosphere (lefaudeux ). halos are expected to occur in the atmospheres of other planets as well. a bright subhorizon halo streak has indeed been observed on mars by an orbiting space probe (fig. ), but that type of halo is due to external reflection at the crystal faces, and thus contains only information about the degree of preferential orientation of the halo-generating airborne martian crystals, not about the composition of these crystals (können ). in , during the descent of the huygens probe through the dense atmosphere of saturn’s moon titan, we were eager to look for halos from methane crystals (können ), but nothing showed up in the images. in fact, at a height of km above the surface, the probe passed through a swarm of particles that were most likely methane crystals (tomasko et al. ), but at that stage of the descent, the sky above the probe was overcast. hopefully, on another occasion the titan weather will be more cooperative. fig. . download figure download figure as powerpoint slide (left) halo in the terrestrial atmosphere. (right) halo in the thin clouds of mars. the white streak in the pictures is the so-called subsun, a halo that appears as an elongated mirror image of the sun in the clouds. it is due to the reflection of sunlight by horizontally oriented crystal faces; see the diagram in the left panel. the picture of the terrestrial subsun is taken from an aircraft; its length (∼ °) indicates a mean tilt angle of ° of the reflecting crystal faces. the mars picture is taken by a scanning platform, causing the martian subsun to be strongly elongated. left photograph taken by m. vollmer on a flight from fairbanks, ak, to frankfurt, germany, at utc aug . solar elevation is ∼ °. the horizontal field of view is °. right photograph taken on jan by the national aeronautics and space administration/jet propulsion laboratory/malin space science systems (nasa/jpl/msss) mars orbiter camera (moc – ), covering an area of km × km on mars. citation: bulletin of the american meteorological society , ; . /bams-d- - . diffraction coronas and glories, and their information content. diffraction coronas. the diffraction corona, not to be mistaken for the much larger halos, consists in its simplest form of a white aureole, with angular diameter of a few degrees, surrounding a light source and terminating in a reddish outer edge (fig. ). sometimes it is surrounded by additional colored rings. the diffraction corona occurs a couple of times during virtually every partially clouded day. many people are familiar with the diffraction corona surrounding the moon but are unaware of its brilliant counterpart surrounding the sun, as one instinctively avoids looking in the close vicinity of the sun. however, with the aid of sunglasses and by blocking the solar disk with one’s thumb, one can see the fine color hues of the sunlight-induced diffraction corona in their full richness. fig. . download figure download figure as powerpoint slide typical diffraction corona around a gibbous moon, during morning twilight. in the naïve and widely applied approach, the angular diameter of the red ring, about . °, which surrounds the white aureole, indicates a particle size of μm. this turns out to be an overestimation by almost a factor of . photograph taken by c. hinz from the mountain wendelstein ( m) in the bavarian alps at utc, min before sunrise, on jan . solar elevation is − . °. the horizontal field of view is °. citation: bulletin of the american meteorological society , ; . /bams-d- - . the corona is caused by diffraction of light by micron-sized cloud particles, in most cases water drops. as is the case for rainbows, the roundness of the diffraction corona is an expression of the sphericity of the drops. the diameter of the diffraction corona is inversely proportional to the drop size. hence, the corona expands where it extends over the smaller drops at the edge of a cloud. intrinsic noncircular coronas exist, occasionally with a marked internal structure (evans ; corliss ; parviainen et al. ), but these small-sized phenomena are caused by oriented pollen instead of by deformed drops (tränkle and mielke ). quantitative values of the drop size can be directly inferred from the diameter of the diffraction corona. this has been frequently done using the diameter of the red ring surrounding the bright central aureole (seen in fig. ). however, as recently pointed out by laven ( ), this ring is not the first diffraction maximum, but instead is the result of the wavelength dependence of the width of the central aureole. therefore the often-applied and seemingly obvious use of fraunhofer diffraction theory to the inner red ring is incorrect and results in an overestimation of the particle sizes by no less than a factor of . it is fascinating that this mistake has remained unnoticed by many for nearly two centuries. glories. the corona has its counterpart on the opposite side of the celestial sphere. this phenomenon is called the anticorona or the glory. its shape resembles the diffraction corona, consisting of a white central area with angular diameter of a few degrees surrounded by a reddish ring, but now the center is at the shadow point (fig. ). sometimes a second or even a third concentric ring is present. fig. . download figure download figure as powerpoint slide typical appearance of a glory as seen from an aircraft. the glory is centered on the shadow of the plane or, better, on the shadow of the camera that took this picture. the distance of the glory’s center below the horizon indicates a solar elevation of . °. the angular diameter of the glory’s inner red ring of about ° indicates a drop diameter of about μm. photograph taken by p. laven at utc mar , shortly after takeoff on a flight from geneva, switzerland, to london, united kingdom. the horizontal field of view is °. citation: bulletin of the american meteorological society , ; . /bams-d- - . the glory is caused by backscattering of light by small drops via a mechanism different than that of the diffraction corona. given the many sightings reported by pilots, it is probably as common as the diffraction corona, but ground-based observers rarely see it. the diameter of the glory is inversely proportional to the drop size. noncircular glories regularly occur, but they are the result of gradients in the droplet sizes in the cloud deck where the glory appears, rather than being an indication of nonsphericity of the tiny drops (fig. ). fig. . download figure download figure as powerpoint slide deformed glory on a cap cloud over the top of a neighboring mountain. the gradients in droplet size cause the formation of a colored sideward extension on the right-hand side of the glory. a detailed analysis reveals drop diameters ranging from about μm in the undisturbed part down to μm in the colored extension (laven b). the picture is contrast enhanced. photograph taken by c. hinz from the mountain wendelstein ( m) in the bavarian alps at utc nov . solar elevation is . °. the horizontal field of view is °. citation: bulletin of the american meteorological society , ; . /bams-d- - . the presence of a glory implies that spherical particles of a certain size are present at the site of its appearance. these spheres have to be transparent in order to create a glory, but somewhat counterintuitively, the structure and diameter of a glory does not contain any useful information about the refractive index, and hence about the chemical composition, of the glory-making particles (laven a). the mechanism causing the glory had remained a mystery for a long time: it was only in that van de hulst formulated the first reasonable model of the formation of this enigmatic phenomenon (van de hulst ). however, it took another half century until the glory was fully understood (laven b)—a clear illustration of the fact that the development and evolution of atmospheric optics is still in progress. glories in the terrestrial atmosphere have been observed from space (floor ; israelevich et al. ; see fig. ) and recently also in the atmosphere of venus (markiewicz et al. ; petrova et al. ). as our exploration of the solar system is still at its very early stage and research on exoplanets is booming, the detection of glories, halos, or rainbows in the atmospheres of planets other than earth, venus, or mars, or even perhaps in the atmosphere of an earth-like exoplanet (karalidi et al. ), seems to be just a matter of time. fig. . download figure download figure as powerpoint slide glory observed from space. the angular diameter of the glory of about ° corresponds to a drop diameter of about μm (laven a). photograph taken above the atlantic by the israeli astronaut i. ramon, on board the ill-fated space shuttle columbia, at : utc jan , days before the crash. the glory’s center is at . °s, . °w, km southwest of liberia. the horizontal field of view of . ° covers km on earth’s surface. the arrow indicates north. (image reproduced with permission of p. israelevich, tel aviv university, tel aviv, israel.) citation: bulletin of the american meteorological society , ; . /bams-d- - . postscript. many aspects of the development in the field in the past years are condensed in the special issues on light and color in the open air that have appeared since every – years in the optical society of america (osa) publications journal of the optical society of america ( – ) and applied optics ( – ). see shaw et al. ( ) for a complete listing of these special issues. references boyer, c. b., : the rainbow: from myth to mathematics. princeton university press, pp. brandes, h. w., : venturi’s theorie des farbigen bogens, welcher sich oft an der innern seite des regenboges zeigt, dargestellt mit einigen anmerkungen. ann. phys., , – , doi: . /andp. . crossref brandes, h. w., : venturi’s theorie des farbigen bogens, welcher sich oft an der innern seite des regenboges zeigt, dargestellt mit einigen anmerkungen. ann. phys., , – , doi: . /andp. . . /andp. )| false search google scholar export citation corliss, w. r., : handbook of unusual natural phenomena. sourcebook project, pp. edens, h. e., : photographic observation of a natural fifth-order rainbow. appl. opt., , b –b , doi: . /ao. . b . crossref edens, h. e., : photographic observation of a natural fifth-order rainbow. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation edens, h. e., and g. p. können, : probable photographic detection of the natural seventh-order rainbow. appl. opt., , b –b , doi: . /ao. . b . crossref edens, h. e., and g. p. können, : probable photographic detection of the natural seventh-order rainbow. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation evans, l., : remarkable lunar halo. quart. j. roy. meteor. soc., , , doi: . /qj. . evans, l., : remarkable lunar halo. quart. j. roy. meteor. soc., , , doi: . /qj. .)| false search google scholar export citation floor, c., : glory from space. weather, , , doi: . /wea. . crossref floor, c., : glory from space. weather, , , doi: . /wea. . . /wea. )| false search google scholar export citation fraser, a. b., : why can the supernumerary bows be seen in a rain shower? j. opt. soc. amer., , – , doi: . /josa. . . crossref fraser, a. b., : why can the supernumerary bows be seen in a rain shower? j. opt. soc. amer., , – , doi: . /josa. . . . /josa. . )| false search google scholar export citation greenler, r., : rainbows, halos, and glories. cambridge university press, pp. großmann, m., e. schmidt, and a. haußmann, : photographic evidence for the third-order rainbow. appl. opt., , f –f , doi: . /ao. . f . crossref großmann, m., e. schmidt, and a. haußmann, : photographic evidence for the third-order rainbow. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation hansen, j. e., and j. hovenier, : interpretation of the polarization of venus. j. atmos. sci., , – , doi: . / - ( ) < :iotpov> . .co; . crossref hansen, j. e., and j. hovenier, : interpretation of the polarization of venus. j. atmos. sci., , – , doi: . / - ( ) < :iotpov> . .co; . . / - ( ) < :iotpov> . .co; )| false search google scholar export citation haußmann, a., : observation, analysis, and reconstruction of a twinned rainbow. appl. opt., , b –b , doi: . /ao. . b . crossref haußmann, a., : observation, analysis, and reconstruction of a twinned rainbow. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation israelevich, p. l., j. h. joseph, z. levin, and y. yair, : first observation of glory from space. bull. amer. meteor. soc., , – , doi: . / bams . . crossref israelevich, p. l., j. h. joseph, z. levin, and y. yair, : first observation of glory from space. bull. amer. meteor. soc., , – , doi: . / bams . . . / bams . )| false search google scholar export citation karalidi, t., d. m. stam, and j. w. hovenier, : looking for the rainbow on exoplanets covered by liquid and icy water clouds. astron. astrophys., , a , doi: . / - / . crossref karalidi, t., d. m. stam, and j. w. hovenier, : looking for the rainbow on exoplanets covered by liquid and icy water clouds. astron. astrophys., , a , doi: . / - / . . / - / )| false search google scholar export citation können, g. p., : polarized light in nature. cambridge university press, pp. können, g. p., : appearance of supernumeraries of the secondary rainbow in rain showers. j. opt. soc. amer., a, – , doi: . /josaa. . . crossref können, g. p., : appearance of supernumeraries of the secondary rainbow in rain showers. j. opt. soc. amer., a, – , doi: . /josaa. . . . /josaa. . )| false search google scholar export citation können, g. p., : titan halos. titan, from discovery to encounter, k. fletcher, ed., esa sp- , – . können, g. p., : a halo on mars. weather, , – , doi: . /wea. . . crossref können, g. p., : a halo on mars. weather, , – , doi: . /wea. . . . /wea. . )| false search google scholar export citation laven, p., a: atmospheric glories: simulations and observations. appl. opt., , – , doi: . /ao. . . crossref laven, p., a: atmospheric glories: simulations and observations. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation laven, p., b: how are glories formed? appl. opt., , – , doi: . /ao. . . crossref laven, p., b: how are glories formed? appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation laven, p., a: effects of refractive index on glories. appl. opt., , h –h , doi: . /ao. . h . crossref laven, p., a: effects of refractive index on glories. appl. opt., , h –h , doi: . /ao. . h . . /ao. . h )| false search google scholar export citation laven, p., b: noncircular glories and their relationship to cloud droplet size. appl. opt., , h –h , doi: . /ao. . h . crossref laven, p., b: noncircular glories and their relationship to cloud droplet size. appl. opt., , h –h , doi: . /ao. . h . . /ao. . h )| false search google scholar export citation laven, p., : re-visiting the atmospheric corona. appl. opt., , b –b , doi: . /ao. . b . crossref laven, p., : re-visiting the atmospheric corona. appl. opt., , b –b , doi: . /ao. . b . . /ao. . b )| false search google scholar export citation lee, r. l., and p. laven, : visibility of natural tertiary rainbows. appl. opt., , f –f , doi: . /ao. . f . crossref lee, r. l., and p. laven, : visibility of natural tertiary rainbows. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation lefaudeux, n. a., : crystals of hexagonal ice with ( - ) miller index faces explain exotic arcs in the lascar halo display. appl. opt., , f –f , doi: . /ao. . f . crossref lefaudeux, n. a., : crystals of hexagonal ice with ( - ) miller index faces explain exotic arcs in the lascar halo display. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation markiewicz, w. j., and coauthors, : glory on venus cloud tops and the unknown uv absorber. icarus, , – , doi: . /j.icarus. . . . crossref markiewicz, w. j., and coauthors, : glory on venus cloud tops and the unknown uv absorber. icarus, , – , doi: . /j.icarus. . . . . /j.icarus. . . )| false search google scholar export citation minnaert, m. g. m., : light and color in the outdoors. springer-verlag, pp. crossref minnaert, m. g. m., : light and color in the outdoors. springer-verlag, pp. . / - - - - )| false export citation möbius, w., : zur theorie des regenbogens und ihrer experimentellen prüfung. ann. phys., , – , doi: . /andp. . crossref möbius, w., : zur theorie des regenbogens und ihrer experimentellen prüfung. ann. phys., , – , doi: . /andp. . . /andp. )| false search google scholar export citation parviainen, p., c. f. bohren, and v. mäkelä, : vertical elliptical coronas caused by pollen. appl. opt., , – , doi: . /ao. . . crossref parviainen, p., c. f. bohren, and v. mäkelä, : vertical elliptical coronas caused by pollen. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation petrova, e. v., s. oksana, w. j. shalygina, and w. j. markiewicz, : the vmc/vex photometry at small phase angles: glory and the physical properties of particles in the upper cloud layer of venus. planet. space sci., – , – , doi: . /j.pss. . . . crossref petrova, e. v., s. oksana, w. j. shalygina, and w. j. markiewicz, : the vmc/vex photometry at small phase angles: glory and the physical properties of particles in the upper cloud layer of venus. planet. space sci., – , – , doi: . /j.pss. . . . . /j.pss. . . )| false search google scholar export citation riikonen, m., m. sillanpää, l. virta, d. sullivan, j. moilanen, and i. luukkonen, : halo observations provide evidence of airborne cubic ice in the earth’s atmosphere. appl. opt., , – , doi: . /ao. . . crossref riikonen, m., m. sillanpää, l. virta, d. sullivan, j. moilanen, and i. luukkonen, : halo observations provide evidence of airborne cubic ice in the earth’s atmosphere. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation shaw, j. a., r. l. lee, and p. laven, : light and color in the open air: introduction to the feature issue. appl. opt., , lc –lc , doi: . /ao. . lc . crossref shaw, j. a., r. l. lee, and p. laven, : light and color in the open air: introduction to the feature issue. appl. opt., , lc –lc , doi: . /ao. . lc . . /ao. . lc )| false search google scholar export citation tape, w., : atmospheric halos. antarctic research series, vol. , amer. geophys. union, pp. crossref tape, w., : atmospheric halos. antarctic research series, vol. , amer. geophys. union, pp. . /ar )| false export citation tape, w., and j. moilanen, : atmospheric halos and the search for angle x. amer. geophys. union, pp., doi: . /sp . crossref tape, w., and j. moilanen, : atmospheric halos and the search for angle x. amer. geophys. union, pp., doi: . /sp . . /sp )| false export citation theusner, m., : photographic observation of a natural fourth-order rainbow. appl. opt., , f –f , doi: . /ao. . f . crossref theusner, m., : photographic observation of a natural fourth-order rainbow. appl. opt., , f –f , doi: . /ao. . f . . /ao. . f )| false search google scholar export citation tomasko, m. g., and coauthors, : rain, winds and haze during the huygens probe’s descent to titan’s surface. nature, , – , doi: . /nature . crossref tomasko, m. g., and coauthors, : rain, winds and haze during the huygens probe’s descent to titan’s surface. nature, , – , doi: . /nature . . /nature )| false search google scholar export citation tränkle, e., and b. mielke, : simulation and analysis of pollen coronas. appl. opt., , – , doi: . /ao. . . crossref tränkle, e., and b. mielke, : simulation and analysis of pollen coronas. appl. opt., , – , doi: . /ao. . . . /ao. . )| false search google scholar export citation van de hulst, h. c., : a theory of the anti-coronae. j. opt. soc. amer., , – , doi: . /josa. . . crossref van de hulst, h. c., : a theory of the anti-coronae. j. opt. soc. amer., , – , doi: . /josa. . . . /josa. . )| false search google scholar export citation venturi, g. b., : commentari sopra la storia e la teorie dell’ottica. pe’ fratelly masi, pp. [available online at www.e-rara.ch/zut/content/titleinfo/ .] view table save email this content ams publications journals bams monographs ams books glossary of meteorology state of the climate explaining extreme events get involved with ams ams online profile publish benefits of publishing with ams author information submit manuscript subscribe member subscription non-member subscriptions institutional subscriptions affiliate sites ams home front page blog living on the real world blog ams weather band follow us contact us contact publishing staff email & phone contacts email: amsjol@ametsoc.org phone: - - fax: - - headquarters: beacon street boston, ma - dc office: new york ave nw suite washington, dc - access brought to you by: carnegie mellon university privacy policy & disclaimer get adobe acrobat reader © american meteorological society powered by pubfactory [ . . . ] . . . sign in to annotate close edit character limit / delete cancel save @! character limit / cancel save aly Ð reflections on sleeping beauty reflections on sleeping beauty frank arntzenius . introduction adam elga ( ) presents a puzzle, the ‘sleeping beauty’ puzzle, which concerns the updating of belief when a person, sleeping beauty, finds some- thing out about her temporal location in the world. he claims that in such cases, even though she apparently only learned something about her tem- poral location in the world, and nothing about the world per se, she should nonetheless change her degrees of belief in what the world is like. and elga claims that in so doing she will violate bas van fraassen’s ‘reflection prin- ciple’. (see van fraassen and van fraassen .) after presenting elga’s argument i will present an alternative argument which has as its conclusion that sleeping beauty should not change her degrees of belief. i will then argue that neither of these arguments by itself is compelling, that one should distinguish degrees of belief from acceptable betting odds, and that some of the time sleeping beauty should not have analysis . , january , pp. – . © frank arntzenius frank arntzenius definite degrees of belief in certain propositions. finally i will argue that the sleeping beauty puzzle has to do with cognitive malfunction rather than with the updating of self-locating beliefs, but that nonetheless the updat- ing of self-locating beliefs is interestingly different from the updating of ordinary beliefs about the world. . sleeping beauty some researchers are going to put sleeping beauty, sb, to sleep on sunday night. during the two days that her sleep will last the researchers will wake her up either once, on monday morning, or twice, on monday morning and tuesday morning. they will toss a fair coin sunday night in order to determine whether she will be woken up once or twice: if it lands heads she will be woken up on monday only, if it lands tails she will be woken up on monday and tuesday. after each waking, she will be asked what her degree of belief is that the outcome of the coin toss is heads. after she has given her answer she will be given a drug that erases her memory of the waking up; indeed it resets her mental state to the state that it was in on sunday just before she was put to sleep. then she is put to sleep again. the ques- tion now is: when she wakes up what should her degree of belief be that the outcome was heads? answer : her degree of belief in heads should be / . it was a fair coin and she learned nothing relevant by waking up. answer : her degree of belief in heads should be / . if this experi- ment is repeated many times, approximately / of the awakenings will be heads-awakenings, i.e. awakenings that happen on trials in which the coin landed heads. . why sleeping beauty should change her mind elga argues that answer is the correct answer. his argument is as follows. when sb wakes up she is certain that she is in one of three predicaments: h : heads and it is monday t : tails and it is monday t : tails and it is tuesday let p represent the degrees of belief that sb should have when she awakens. suppose that when she wakes up she learns that the outcome is tails. by the symmetry of the situation she ought then to have degree of belief / that it is monday, and degree of belief / that it is tuesday. thus p(t / t or t ) = / . and hence p(t ) = p(t ). alternatively suppose that when she wakes up she learns that it is monday. it seems that then she still ought to have degree of belief / that the outcome was heads. in fact elga gives an apparently compelling argu- reflections on sleeping beauty ment for this conclusion, by considering a slightly different case. suppose that the coin is tossed on monday night rather than sunday night. if it comes up heads sb will not be woken up on tuesday, if it comes up tails she will be woken up on tuesday. whether the coin is tossed on sunday night or monday night ought to make no difference to her degrees of belief. but it is clear that if she learns that it is monday, and she knows that a fair coin is to be tossed on monday night, then she ought to have degree of belief / that it will come up heads. now, learning that it is monday amounts to learning that she is in h or t . thus p(h /h or t ) = / . and this entails that p(h ) = p(t ). altogether we therefore have p(h ) = p(t ) = p(t ) = / . the surprising consequence of this argument is that she started out on sunday with a degree of belief / in heads, and by merely waking up she has changed her mind: she has switched her degree of belief to / , despite the fact that she received no new information about the world. (here ‘no new information’ means: ‘no new non-self-locating information’.) this violates bas van fraassen’s ‘reflection principle’, which entails that if a person p is now certain that tomorrow p will have degree of belief x in r, while suffering no ‘cognitive mishaps’ between now and tomorrow, then p ought to now have degree of belief x in r. elga’s explanation of these sur- prising consequences is that in sleeping beauty type cases ‘you have gone from a situation in which you count your temporal location as irrelevant to the truth of h, to one in which you count your own temporal location as relevant to the truth of h.’ ( ). frankly speaking, this ‘explanation’ still leaves me puzzled. . why sleeping beauty should not change her mind i will now quickly argue that sleeping beauty should not change her mind, that is, that she should maintain degree of belief / in heads when she wakes up, and then spend some time defending this argument against objections. the argument is simple: sb gains no new information that is relevant to the outcome of the coin toss, she should not violate condition- alization and/or reflection, and hence her degree of belief upon waking up should be what it was on sunday, namely / . (for a more elaborate and explicit version of this argument see lewis .) a first worry about this argument is that if it is compelling, then elga’s argument had better be faulty. i will postpone discussion of that issue to the next section. a second worry is that in the long run / of sb’s awakenings will be tails- awakenings. thus, if she bets according to her degree of belief of / , she can be expected to lose money against a bookie, and she and the bookie know this in advance. i will argue that the resolution of this worry is that she should bet at odds that differ from her degrees of belief, and that this frank arntzenius is perfectly consistent with standard bayesian lore. i will argue for this by means of some examples. suppose that a bookie comes to you on sunday and allows you to bet at : odds on the toss of a fair coin on monday, where you can nominate which side you are betting on. here : odds means that you win $ if it lands on the side you nominate and you lose $ if it lands on the other side. clearly you should not accept. next, the bookie gives you a slightly different offer. he still offers you a bet at : odds. but now the absolute value of the bet depends on the outcome of the toss in the following way: if the toss lands heads the bet is $ versus $ , if the coin lands tails the bet is $ versus $ . now you should be indifferent as to whether you accept the offer, and if you do accept the offer you should nominate tails. for if you do that and it lands heads, then the bet is $ versus $ , so you loose $ , while if it lands tails the bet is $ versus $ and you win $ . so you loose $ or win $ , and each is equally likely. though this case does not seem as puzzling as the sleeping beauty case, there is something puzzling about it. if you accept the offer on sunday, then there is a % chance that you are committing yourself to bet a on monday, and there is a % chance that you are committing yourself to bet b on monday, where each of bets a and b are bad bets according to your degrees of belief. the puzzling thing is that this commitment is nonetheless not a bad commitment. this may seem less puzzling when you realize that this commitment can be re-described as a choice, made by you on sunday, to accept bet # of the following two bets that you are offered: bet# : you bet on tails: you win $ , or loose $ bet# : you bet on heads: you win $ , or loose $ . nonetheless it remains the case that if you accept the offer on sunday you are committing yourself to one of two possible bets on monday, each of which is bad according to your degrees of belief. the next example is the sleeping beauty example, except that each time that sb is woken up she is not asked for her degrees of belief in tails, instead she is asked whether she is willing to accept a bet at : odds on tails. sb should be indifferent, since the structure of this case is exactly the same as the case above. in the variable stakes bet, by direct stipulation, the poten- tial gains and losses are multiplied by when it is tails; in the sleeping beauty case the potential gains and losses are multiplied by when it is tails because sb is twice asked the same question, and is bound to give the same in email exchanges i have learned that jamie dreyer has invented essentially the same example (his ‘variable stakes casino example’) before i did. reflections on sleeping beauty answers. this suggests that sb’s degrees of belief in heads upon waking up should remain unchanged at / , but that nonetheless upon waking up she should accept any bets on tails at odds of : or better. one might still be worried: doesn’t betting at odds that are bad according to one’s degrees of belief violate standard decision theory? let me give yet another example to explain why it needn’t. let us make three changes to the sleeping beauty case. in the first place let us assume that sb is offered a bet on tails at : odds (rather than : odds) each time she wakes up. secondly, there is another person, dormant belle, db, who is placed in exactly the same situation as sb is: she is offered the very same bets (on the very same coin toss) that sb is offered, and her memory will be erased after she accepts or declines a bet etc. thirdly, the payoff structure is altered. sb gets the gains or losses of her first bet, and of db’s last bet, if there is one. db gets the gains or losses of her first bet, and the gains or losses of sb’s last bet, if there is one. db and sb don’t know each other, but they each know that there is another person in the same situation as they are, and they each know what the payoff structure is. each is supposed to care only about the profits or losses that they themselves make. what should sb (and db) do? the answer is that sb upon waking should not accept a bet offered at : . the profits or losses that sb makes on db’s last bet, if there is one, are independent of sb’s choice whether to accept a : bet when sb wakes up. so sb needs only to decide for or against the acceptability of a single bet (on monday). she either gains $ or loses $ on that bet, depending on the outcome of a toss of a fair coin. so she should not accept the bet. db, if she is sensible, will reason the same way. it is a prisoners’ dilemma. let us next change the example a little bit. suppose that db is sb’s iden- tical twin sister and that both believe that whatever the one decides, the other will decide the same. should each accept the bet? well, that depends on what they regard as the correct decision theory. on a simple-minded version of evidential decision theory they ought both to accept the bet, since if both accept the bet, each either wins $ or loses $ , and each is equally likely. on the other hand, according to causal decision theory they should not accept. for holding fixed what the other does, no matter what the other does, each should expect to do better (by $ . per trial in the long run) by not accepting. now let us return to the standard sleeping beauty case. let us start by supposing that sb is an evidential decision theorist, and that sb accepts that her agreeing to a particular bet on one particular awakening is good evi- dence that she will agree to it upon the other awakening, if there is one. thus, her acceptance of a bet on a particular awakening has two beneficial consequences if in fact the coin lands tails: she will win that particular bet, and she will make that bet again and win it again, upon her other awak- frank arntzenius ening. so if sb accepts evidential decision theory she should accept a bet on tails at : odds, even though her degree of belief in tails is / . in contrast let us suppose that sb is a causal decision theorist. clearly sb’s acceptance of a bet on tuesday does not cause her acceptance of that bet on monday. moreover it is implausible to claim that her acceptance of a bet on monday causes her to accept that bet on tuesday, since it is more plausible to claim that both acceptances have a common cause, namely sb’s mental state on sunday. so let us suppose that sb does not believe that her acceptance of a bet any one day causes her acceptance of such a bet on the other day. let us furthermore suppose that sb accepts a rather strict version of causal decision theory, namely one according to which a ‘dependency hypothesis’ (see lewis ) consist of a listing of the causal effects of sb’s possible actions. given sb’s acceptance of such a causal decision theory, and given her belief that acceptance of a bet on any one day does not cause her acceptance on any other day, she should, upon waking up, not accept a bet at odds that differ from her degrees of belief. as a final example, let us suppose that sb believes that any acceptance of any bet on any one day is counterfactually connected to such an accep- tance on the other day, i.e. let us suppose that sb accepts the claim ‘if i were to accept this bet now, then i would accept it upon any other such waking’. and suppose that sb accepts ‘counterfactual decision theory’, i.e. a causal decision theory according to which counterfactual dependencies are the relevant dependencies. then sb will accept bets at odds that differ from her degrees of belief, e.g. a bet on tails at odds : even though her degree of belief in tails is / . so, one can hold on to van fraassen’s reflection principle, and to bayesian updating by conditionalization, as long as one does not adhere to a strict version of causal decision theory. does this mean that we have an argument from the premiss of ‘van fraassen reflection’, or from the premiss of ‘bayesian conditionalization’, to the conclusion that strict causal decision theory is false? that would be surprising! or should one instead conclude that causal decision theory is correct, that sb’s degree of belief in heads should be / , but that sleeping beauty is one of those strange cases where a causal decision theorist is punished for her rationality, and pre- dictably so? that would be interesting! but before jumping to conclusions, let us take a step back. . why sleeping beauty may, or may not, change her mind if the coin lands tails on monday night sb’s degrees of belief will be reset to what they were on sunday night. thus, if the coin lands tails, then sb, from a bayesian point of view, will have a cognitive malfunction: she will violate conditionalization. since she knows this in advance (and all the reflections on sleeping beauty time) the obvious question is: what should she do to avoid ‘damage’ as much as she can? before discussing what the best damage control strategy is for sb, let me, in the light of the noted cognitive malfunction, explain what is wrong with the views expressed in the previous two sections. what is wrong with elga’s argument that sb should change her mind upon waking up? well, elga’s argument assumes that if sb were to learn that it is monday she should arrive at her new degrees of belief by condi- tionalizing the degrees of belief she has when she wakes up. and it assumes that, were she to learn that it is tails, she should arrive at her new degrees of belief by conditionalization from the degrees of belief she has when she wakes up. this argument would be fine if indeed sb could be a good bayesian throughout. but the conclusion of elga’s argument is that sb should not be a good bayesian, since she should violate reflection, and should violate conditionalization on the transition from sunday evening to monday morning after wake-up. moreover, it is inevitable that, if the coin lands tails, then on the transition from monday to tuesday sb will violate conditionalization, since her degrees of belief will be artificially reset. what’s more, if sb follows elga’s advice for her degrees of belief and she happens to be an evidential decision theorist she can expect to loose money. so elga’s argument is not compelling. what is wrong with my argument that sb should not change her mind upon waking up? in essence, it has the same problems as elga’s argument. i argued that sb should not change her mind, by assuming the validity of van fraassen’s reflection principle, and by assuming that her degrees of belief upon waking up come from her degrees of belief on sunday by conditionalization. since there is nothing (relevant) to conditionalize upon when she wakes up, her non-self-locational degrees of belief must remain the same upon waking up. this would be a fine argument if sb could always update by conditionalization. but she can’t. moreover if she accepts my argument and happens to be a strict causal decision theorist, she can expect to lose money. so my argument is not compelling. so let us look afresh at the question as to what sb should do. as should be obvious, there are several options. for instance, even while admitting that elga’s argument and my argument for the above two views are incon- clusive, sb could still decide to adopt one or the other of those degrees of belief on different grounds. but let me also mention some other options, before lurching towards resolution. when she wakes up she could do exactly what she would do on monday morning if she had no worries about cognitive malfunctions, namely update her location belief to ‘it is now monday’, and leave her degrees of belief in heads the same. if she does this she will have no cognitive damage on monday: on monday morning she will have exactly the beliefs that a person p would have who does not have to worry about possible cognitive frank arntzenius malfunction. note that this procedure is not the same procedure as advo- cated in the previous section. for on the view advocated in the previous section sb should not have degree of belief in ‘it is monday’ upon waking up, while on the view currently under consideration she should. the current view has the advantage that sb suffers no cognitive damage what- soever on monday. but then, of course, on a tuesday morning wake-up, if there is one, she would have severe cognitive damage: she would have the very same degrees of belief as she had on monday, and those are not the degrees of belief that a person who functions cognitively perfectly through- out, would have on a tuesday wake-up. one can think of many such schemes, and each will include some cognitive damage as compared to a perfectly functioning individual. so let us look more closely at the issue of damage control in order to get some grip on a preferred scheme. on sunday sleeping beauty can contemplate all the bets that she might be offered on future days. suppose that she is forced to accept bets when she wakes up, for example, because a gun is pointed at her head, and she is told that she has to state the odds at which she is indifferent as to which side of the bet she takes. now suppose that these bets are offered by a bookie who adjusts the offered bets according to the outcome of the toss, which he knows. then, of course, the bookie can make sb lose money, and there is no relevant damage control possible. but suppose this is done by a bookie who does not adjust the offered bets to the outcomes. then, given sb’s degrees of belief on sunday, she ought to be able to figure out what the best strategy should be with respect to such possible future bets. now, let us ensure that sb does not learn anything about which day it is from the bet that she is offered, by assuming that sb is certain that what- ever bet she is offered she will be offered the same bet on monday as on tuesday. then it should be clear which bets sb should accept upon waking up. for she knows that in the long run, if the situation were repeated, there will be / heads-awakenings, and / tails-awakenings. since she will always accept or reject the same bets, she has good reason to accept only bets on tails at : odds (gain if it is tails, lose if it is heads), or better. so she knows what bets to accept upon waking up. what about her degrees of belief upon waking up though? well, we have seen above that if sb has degree of belief / in heads, and accepts strict causal decision theory, she will indeed accept bets on tails at : odds or better. but we have also seen that if sb has degree of belief / in heads, and she accepts strict evidential decision theory, then she will also accept bets on tails at : odds or better. and there are some other possible combinations that will have her accept bets on tails at : odds or better. one possible sug- gestion therefore is that sb should, upon waking up, simply set her degrees of belief to whatever they need to be, given the decision theory and depen- reflections on sleeping beauty dencies that she accepts, in order for her to find acceptable bets on tails at : odds or better. however, it seems rather odd that sb’s degrees of belief would depend on the decision theory that she accepts. surely if she changes her mind about which decision theory is correct she should not thereby be forced to change her epistemic state with respect to heads. surely changing her mind about decision theory does not entail changing her mind as to what the world is like with respect to outcomes of coin tosses. thus it seems more plausible to say that her epistemic state upon waking up should not include a definite degree of belief in heads. she should of course know which bets she should accept and which ones she should not, but her epistemic state does not include a natural candidate for a context-independent degree of belief in heads. in fact her epistemic state upon waking up is best described by saying that she believes that she is in the situation described in the sleep- ing beauty story. not to have a definite degree of belief in heads might be strange, but it might be the best that she can do given the forced irra- tionality that is inflicted upon her. finally, as should be clear by now, on my view self-locating learning plays no relevant role in the sleeping beauty case. the real issue is how one deals with known, unavoidable, cognitive malfunction. but i still think that there is something interesting and new about self-locating learning. for instance, suppose that one knows exactly what the world is like and exactly where one is in the world. then let some time lapse. if one is not looking at a clock, one will typically no longer be certain what time it is, and hence where one is in the world, and one would not normally call this a cogni- tive malfunction. nonetheless, this change in one’s cognitive state is not due to conditionalization. moreover, it includes a transition from total cer- tainty to uncertainty. that is a new form of cognitive change incompatible with conditionalization, which is not really ‘learning’, but nonetheless in a rather literal sense consists of ‘updating’. this means that standard bayesian lore, after all, does have to be modified in order to deal with self- locating beliefs. however, that is not the main moral of the sleeping beauty story. the main moral of that story is that in the face of forced irrational changes in one’s degrees of belief one might do best simply to jettison them altogether. rutgers university new brunswick, nj - , usa arntzeni@rci.rutgers.edu many thanks to adam elga, brad monton, ned hall, jamie dreyer and bas van fraassen for some useful email exchanges on the sleeping beauty puzzle. e. j. lowe references elga, a. . self-locating belief and the sleeping beauty problem. analysis : – . lewis, d. . causal decision theory. australasian journal of philosophy : – . lewis, d. . sleeping beauty: reply to elga. analysis : – . van fraassen, b. . belief and the will. journal of philosophy : – . van fraassen, b. . belief and the problem of ulysses and the sirens. philosophical studies : – . analysis . , january , pp. – . © e. j. lowe bayesian beauty erkenntnis https://doi.org/ . /s - - - original research bayesian beauty silvia milano received: may / accepted: december © the author(s) abstract the sleeping beauty problem has attracted considerable attention in the literature as a paradigmatic example of how self-locating uncertainty creates problems for the bayesian principles of conditionalization and reflection. furthermore, it is also thought to raise serious issues for diachronic dutch book arguments. i show that, contrary to what is commonly accepted, it is possible to represent the sleeping beauty problem within a standard bayesian framework. once the problem is correctly repre- sented, the ‘thirder’ solution satisfies standard rationality principles, vindicating why it is not vulnerable to diachronic dutch book arguments. moreover, the diachronic dutch books against the ‘halfer’ solutions fail to undermine the standard arguments for conditionalization. the main upshot that emerges from my discussion is that the disagreement between different solutions does not challenge the applicability of bayesian reasoning to centered settings, nor the commitment to conditionalization, but is instead an instance of the familiar problem of choosing the priors. introduction adam elga ( ) introduced to the philosophical literature what has come to be known as the sleeping beauty problem: some researchers are going to put you to sleep. during the two days that your sleep will last, they will briefly wake you up either once or twice, depending on the toss of a fair coin (heads: once; tails: twice). after each waking, they will put you back to sleep with a drug that makes you forget that waking. when you i am very grateful to christian list, anna mahtani, richard bradley, aron vallinder, bryan roberts, and two anonymous referees for their comments on earlier drafts of this paper, as well as the audiences at the lse choice group, elp konstanz, edinburgh graduate epistemology conference, chps at cu boulder, the mcmp logic colloquium, and the participants in the formal epistemology and decision theory workshop at bristol. b silvia milano silvia.milano@oii.ox.ac.uk university of oxford, st. giles’, oxford ox js, uk http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf http://orcid.org/ - - - s. milano are first awakened, to what degree ought you believe that the outcome of the coin toss is heads? (elga , p. ). since then, the sleeping beauty problem has attracted considerable attention in the literature as a paradigmatic example of how self-locating uncertainty creates problems for the principles of conditionalization and reflection. the current consensus is that self-locatinguncertaintyputspressureonthestandardbayesianframework(titelbaum , ; spohn ; schwarz ). while there is no general agreement on a solution, those that have been proposed all raise some tension between different bayesian commitments. the ‘thirder’ solutions (see sect. . below) appear to violate standard conditionalization and reflection, and yet are not vulnerable to diachronic dutch books (see e.g. bradley and leitgeb ; bovens and rabinowicz ). this is at odds with a well known result (teller ( ), who attributes the idea to d. lewis). see also lewis ( ), skyrms ( ), which establishes that an agent can avoid being vulnerable to diachronic dutch books only by planning to update via conditionalization. on the other hand, it is often accepted that ‘halfers’ should not bet at the odds that reflect their beliefs in cases like the sleeping beauty (bradley and leitgeb ; briggs ). but this puts pressure on the idea that an agent’s credences can generally be interpreted (or operationalised) as the betting odds that the same agent would consider fair, undermining a standard argument for probabilism (de finetti ). the current state of the literature indicates that the issues raised by the sleeping beauty problem constitute a serious threat to the bayesian approach to subjective probability. the puzzle is compounded by the fact that self-locating beliefs are perva- sive, and they are key to modelling ordinary evidence, which normally comes in the form of indexical observations (e.g. ‘it is raining now’, ‘this coin toss landed tails’). giventhisbackground,thispapermakestwocontributions.firstly,igiveabayesian representation of the sleeping beauty problem (sect. ), and show that the different numerical solutions discussed in the literature can all be derived within this frame- work, depending on the choice of priors (sect. ). secondly, i show that, despite the appearances, sleeping beauty does not call into question the bayesian commitment to conditionalization. this is done in two steps. i first defend the thirder solution and address the objection that it violates the principles of conditionalization and reflec- tion (sect. ). i then show that diachronic dutch book arguments against the halfer solution do not provide a counterexample to the results by lewis and skyrms (sect. ). before proceeding further, i should also be clear on the limitations of this paper. i do not aim to give a comprehensive review of the vast literature on the sleeping beauty problem. moreover, i will only be interested in solutions that aim to pre- serve the validity of standard bayesian commitments, and specifically the principle of conditionalization. i will not consider the merits of the (numerous) other existing revisionary approaches that propose alternatives to conditionalization here, as well as those of solutions that do not rely on a bayesian framework (such as, for instance, the objectivist one discussed in oscar seminar ). instead, my goal is simply to show that it is possible to represent the sleeping beauty problem within a bayesian framework, and that this representation is consistent for an overview of some of these, see e.g. titelbaum ( ). bayesian beauty with the bayesian commitments to conditionalization and reflection. given that the bayesian framework is widely regarded as a powerful framework for reasoning under uncertainty, and that there are independent reasons for accepting conditionalization and reflection, the results i present shift the burden of proof to those that want to argue for a departure from these principles. the problem elga’sdescriptionofthesleepingbeautyproblemgrantsthefollowingnaturalassump- tions: . the experiment lasts two full days, from the moment beauty is put to sleep at the end of day , to the moment when she is woken up and dismissed at the beginning of day . . there are two possible outcomes to the experiment: either the coin toss comes up heads, and beauty is woken up on day , but left to sleep on day ; or the coin toss comes up tails, and beauty is woken up both on day and on day . each outcome has a prior probability that is equal to . . when she wakes up during the experiment, beauty does not know which day it is. from beauty’s standpoint, the task is to determine the probability of heads, after she wakes up during the experiment. on each day, beauty could be in either of two states: she is either awake or she is asleep. representing an awakening by w and a sleep-through by s, we know from the outset that day involves an awakening, while day may involve either an awakening or a sleep-through, depending on the result of the coin toss. a first characterisation of the state space for the whole experiment is therefore: � = {ws, ww} let h = {ws} be the event that the coin toss comes up heads and t = {ww} be the event that the coin toss comes up tails. by assumption , the prior probability of h is the same as the prior probability of t , that is, p(h) = p(t ) = . in the context of the experiment undergone by sleeping beauty, the probabilities of the events h and t are given as priors, as they are fixed by the experimental setup. during the course of the experiment, beauty is allowed to make some observations that potentially provide her with side information about the outcome of the experiment. each observation consists in waking up on a given day, and noting that ‘beauty wakes up today’, where ‘today’ picks out a day i ∈ { , }. (recall that, by assumption , beauty does not know which day it is when she wakes up, and that by assumption each outcome spans over two days. so, beauty believes that ‘today’ could be either day or day .) how does this observation affect the probability of h? in order to answer this question, we need to represent the observation that ‘beauty wakes up today’ (i.e., ‘beauty wakes up on day i ∈ { , }’) as an event within the same state space as the event h. let us call this event w . a quick glance at � reveals that without some further elaborations, that space is not sufficiently rich to express the event w . s. milano this is because, if the outcome of the experiment is ws (if, that is, the result of the coin toss is heads), it is indeterminate whether beauty wakes up on day i. to see this, consider how the outcome ws consists of an awakening followed by a sleep-through, so for i = , beauty wakes up, but for i = , beauty does not wake up. the difficulty with modelling the event w that beauty wakes up on day i (‘today’) is due to the fact—expressed by assumption —that beauty does not know which day it is when she wakes up. to represent her uncertainty, we need to refine the outcome space, taking into account that the experiment spans over two days (assumption ), and that it could be either day or day , since the experiment lasts two days regardless of the result of the coin toss. the resulting refined state space is: � ′ = {ws , ws , ww , ww } here, the elements of the state space are indexical states, centred on different times. relative to �′ we can express the event w as the set of states {ws , ww , ww }—these are all the states in which beauty is awake during the experiment. w is false at ws , which corresponds to the state where the result of the coin toss is heads, it is day , and beauty is sleeping. the event corresponding to a heads result of the coin toss is h = {ws , ws }, while a tails result corresponds to t = {ww , ww }. the same prior constraints set by the experimental setup should apply to the refined state space �′, as they did to the more coarse-grained version of the state space �. in particular, by assumption , the probabilities assigned to h and t relative to �′ should be equal. table summarises the refined state space and the probabilities associated to each outcome, subject to the constraint that p(h) = p(t ) = . theparameters α and β intable bothtakevaluesinthe [ , ] intervalandrepresent the conditional probability that it is day , given that the result of the coin toss is either heads or tails; more precisely, p(d |h) = α and p(d |t ) = β. expressing the in a sense, speaking about refining the state space may seem suspicious: after all, ws and ws both happen (sequentially) if the result of the coin toss is heads. so, from an atemporal point of view, they are not mutually exclusive. however, here we are not interested in the atemporal viewpoint, but in the temporally located viewpoint that beauty occupies at the time that she considers the problem. from this temporally located perspective, ws and ws are indeed mutually exclusive. the indexical states within the state space �′ can be interpreted as centred worlds. using centred worlds to capture the content of self-locating propositions is a standard move in the philosophical literature lewis ( ). however, the present model is also compatible with other ways of interpreting indexical content, such as for instance as fregean propositions (see, e.g. magidor ). the limited space of this paper does not allow me to detail this discussion, but i develop this point further elsewhere. a possible objection that could be moved against this step is the following: assumption constrains the probabilities of the uncentred events heads and tails, which are perfectly captured in the state space �. but once we move to the centred state space �′, it is unclear why the same constraint should apply. in other words, assumption constrains prior uncentred probabilities, but not necessarily the centred probability of the events once we move to the (centred) space �′. i do not find this objection convincing, for at least two reasons. first, distinguishing between ‘uncentred’ and ‘centred’ reasoning about events such as h and t would make it unclear what are the agent’s true prior probabilities, when they could differ. second, it is not at all clear why we should interpret assumption as applying preferentially to events defined in �. reading it as applying to the events in �′ is at least as natural, and supports my argument that �′ is the right state space to capture the relevant events in the sleeping beauty case. in light of these, we should preserve correspondence between the prior probabilities assigned to uncentred events relative to both state spaces, as breaking it would have higher costs and is not warranted by anything in the problem description. bayesian beauty table the sleeping beauty problem outcomes (heads) (tails) ws ws ww ww probabilities α ( − α) β ( − β) probabilitiesassignedtotheelementsofthestatespaceintermsofthesetwoparameters is not necessary, as we could instead just focus on the probability that is assigned to each element of the state space in isolation. however, introducing the parameters α and β is convenient simply because it preserves the equal probability ratio between the hypotheses h and t , making sure that their respective prior probabilities remain fixed however we distribute probabilities to the events within this partition. the conditional probabilities expressed by α and β are not fixed by the experimental setup, so the description of the problem leaves us free, in principle, to set them however seems best. one might worry, however, that the state ws could never be experienced by sleeping beauty, and so should not be part of the space of possibilities. i will address this worry in the next subsection, but note for now that as long as we accept that all the states in �′ represent logical possibilities, the description of the experimental setup does not give explicit information regarding how beauty should apportion these probabilities, and therefore we should, at this stage of representing the problem, leave open how she sets the values of both α and β. a discussion of which are the correct or the most plausible values for these parameters is left until later (see sect. below). we are now in a position to formally state the problem (which we originally for- mulated as: what probability should beauty assign to heads, given that she wakes up today?) in terms of computing the posterior probability of h, given that w is observed, or p(h|w ). by bayes’ theorem, we immediately have: p(h|w ) = p(w |h)p(h) p(w ) since h and t partition the outcome space �′, by the law of total probability we have that: p(w ) = p(w |h)p(h) + p(w |t )p(t ) moreover, we know that p(h) = p(t ) = , p(w |t ) = (since beauty wakes up every day if t ) and p(w |h) = α (since the probability that beauty wakes up, given that the coin toss comes up heads, is equal to the probability that it is day given h). the previous equation simplifies to: p(w ) = + α ( ) the solution to the sleeping beauty problem is therefore given by the equation: p(h|w ) = α + α ( ) s. milano answering sleeping beauty’s original question therefore depends solely on the value that we assign to parameter α. . further questions the original sleeping beauty problem involves computing the value of h given that w is observed. but once this is done, there are many questions we can still ask. for example, what credence should beauty assign to the coin toss having come up heads, if after waking up she were informed that it is day ? or, similarly, what would her credence in heads be if the experimenters told her, after waking her up, that today is the last time she wakes up during the experiment? another advantage of the refined state space �′ is it allows us to model these further questions. the first question (what is the probability of heads, if today is day ?) can be answered by computing the posterior probability of h, given d ∩ w (which coincides with d ): p(h|d ) = α α + β ( ) let l = {ws , ww } be the event that sleeping beauty wakes up for the last time. to answer the second question (what is the probability of h, if today is the last time you wake up?), we just need to compute the probability of h, given the information that l is the case, which is: p(h|l) = α + α − β ( ) another question that will be interesting to consider might be posed to beauty before the experiment actually begins: suppose that it is either day or day . what is the probability that you wake up? in order to answer this question, beauty should effectively state what is the prior probability of w , on the supposition that it is either the first or the second day (that is, given d ∪ d ). since d ∪ d = �′, the conditional probability of w given d ∪ d is equal to its unconditional probability: p(w |d ∪ d ) = p(w ) ( ) things are a bit different if the question specifies which particular day is to be supposed, e.g. suppose it is day (day ). what is the probability that you are awake? in this case, since we know that p(d ) = α+β and p(d ) = −α−β , by a simple calculation we have: baratgin and walliser ( ) propose a solution to the sleeping beauty problem that is formally similar to eq. . a difference between their approach and the one presented here is that they assume that the probabilities of {ww } and {ww } are both equal to by the restricted principle of indifference (an assumption that, as i argue, we should dispense with). because they do not consider parameter β, their approach is also not able to rationalise the double halfer solution (hawley ), which is possible within my approach (see note in sect. . below). bayesian beauty p(w |d ) = p(w |d ) = − β − α − β ( ) equation states an interesting result. the probability that beauty wakes up, given that it is day , is equal to —just as we would expect, since the experimental setup specifies that beauty always wakes up on day . however, the probability that beauty wakes up on day does not necessarily equal , as this depends on what values α and β take. . prior perspectives before we move on, i want to consider two worries that might arise in relation to my construction of the state space �′ to represent the sleeping beauty problem. one worry is that one of the elements of �′, namely ws , is not compatible with beauty’s evidence at any point in time. since beauty is asleep in ws , she could never consciously experience being in that state. in other words, we could say that ws is a ‘blind’ state: beauty could never learn that this is her current state, and any evidence that she might have while she is awake automatically rules out ws . but, then, maybe we should not consider ws to be a genuine epistemic possibility for beauty, and it should not be included in the state space �′ at all. another, perhaps related, worry is that the state space �′ is only available to beauty when she wakes up, but not before, as none of the states in �′ are compatible with beauty’s evidence before being put to sleep, when she is certain about the current time. this is a serious worry because, if �′ is not always available to beauty, then it would be unclear in what sense we can speak of her having prior probabilities relative to �′, upon which she may conditionalize after learning new evidence during the course of the experiment. let us start by addressing the first worry, that ws may not be a genuine epistemic possibility for beauty, since she could never learn that she is in that state. first of all, there are some prima facie objections to the claim that we could not assign positive probability to ‘blind’ states that are logically possible. consider the following case. suppose you are preparing to leave for a journey, and buying travel insurance brings you to mind the possibility that your flight will crash. given what you believe about the chances of an accident, you assign a positive probability to the possibility of your own death. this, however, is not a proposition that you are in a position to ever learn. so, in some cases at least, it seems plausible to assign a positive probability to ‘blind’ states. further to this, whether we should include ‘blind’ states such as ws in the state space and whether they should be assigned a positive probability are two issues that can be kept separate. in the construction of �′, and in what follows, i assume that the state space contains all the logically possible states, including those that (like ws ) may never represent live epistemic possibilities for beauty. this still leaves open the option of assigning zero probability to these states. doing this in the sleeping beauty case would support lewis’s solution to the problem, as we will see in sect. . below. the second objection—that the state space �′ is not available to beauty before being put to sleep—raises a more general worry for my approach. in one sense, this worry reflects a common intuition: namely, that the experience of being in one of the s. milano states in �′ is only available to beauty when the state occurs, and it is not available to her at earlier (or later) times. in other words, beauty could not make the observation that ‘today is day ’ before being put to sleep. this observation is not compatible with her circumstances before the experiment starts, when she is certain that the current time is not day . but the idea that observations may not be available at all points in time should not be particularly surprising. suppose that you are considering whether to pack a warm sweater for an upcoming trip: you may look up the weather forecast at your destination, and decide to pack it on the basis of the probability that you come to assign to the proposition that it will be chilly in vienna at the time of your visit. in other words, you make a decision now, based on the expectation (formed on the basis of the weather forecast) that you will experience a chilly day when you travel to vienna. the observation ‘it is chilly today in vienna’ is not available to you now. but what is relevant for you now is the expectation of experiencing this state in the future. this can be modelled by your assigning a conditional probability to the proposition ‘it is chilly’, conditional on it being the day when you visit vienna. if this conditional probability is sufficiently high, based on your current estimates, then you will pack a warm sweater. similarly for sleeping beauty, the observation ‘i am awake and today is day ’ would only be available to her on the first day of the experiment—she could not experience these circumstances at any other times. but the expectation of making this experience is available (and relevant) to her at other times, specifically before being put to sleep, and it is equal to the conditional probability that she assigns to being awake, given day , or p(w |d ). a natural objection to what i just said will be that beauty is certain that it is not day on (what we will call) day , before being put to sleep. so, the conditional probability of w , given d , is simply undefined, since on day p(d ) = . of course, i do not want to deny that, on day , beauty should be certain that it is not day . but notice that, by the same reasoning, it would also seem that we have an argument for the claim that, in the sweater case, the probability that it is chilly in vienna when i am there is undefined. the way in which we should solve the issue, i propose, is to allow beauty’s prior probabilities tobedefinedas aconditional probabilitystructure, assigningprobabilities to each logically possible state, conditional on different times, as is implicit in my construction of the sample space �′. this proposal, versions of which have been discussed in the literature on self-locating beliefs (see moss ; stalnaker ; meacham ; schwarz ; wenmackers ), has the advantage of allowing to be precise, to model beauty’s beliefs on day we should expand the state space to include a time point relative to day . consider the resulting expanded state space �′′ = {ws , ws , ws , ww , ww , ww }: since p(d |d ) = , and since d and d are mutually exclusive events, p(d |d ) has to be equal to . the expanded state space �′′ can be used to more accurately model beauty’s credences before being put to sleep, but since the propositions that we are interested in are those relative to her states during the experiment (that is, conditional on it being either day or day ), there is no loss in using �′ to solve the equations in sects. – . . see also horgan ( ) and neal ( ) for related discussions. the ‘generalised conditionalization’ principle defended by horgan differs from standard conditionalization by its reliance on what horgan calls ‘preliminary probabilities’, which are distinct from prior probabilities. horgan defends the thirder position, but as i show the halfer position is also consistent with conditionalization. bayesian beauty for a unified and straightforward treatment of both cases like ‘sweater’ and sleeping beauty. having clarified the nature of beauty’s priors, in the next section i turn to the task of deriving a numerical solution within the framework i have presented. solution as we’ve seen in the previous section, the solution to the sleeping beauty problem comes down to computing the value of p(h|w ) in eq. . to do this, we need to specify what is the value of α, which is not explicitly fixed by the description of the experimental setup. is there a correct or most plausible assignment of value to α? moreover, does the value assigned to α match the value assigned to β, or do they differ? (although the value of β does not matter to the solution of the original sleeping beauty problem, it affects the solution to the further questions i described in the previous section.) there are, i think, two possible ways to go from here. one possibility would be to say that we simply cannot assign any value to α and β, since these are left unspecified by the description of the experimental setup. this would leave us unable to compute the posterior probability of heads given that beauty wakes up. although theoretically coherent, this solution is not very attractive. a second way to go is to proceed and assign a value to α (and to β, if we have any interest in answering the further questions that sleeping beauty might consider, described in sect. . ). if we take this route, it remains to be decided which values are the most appropriate. the most natural assignment—in my view—is α = and β = . the rationale for this assignment is the following. since beauty is uncertain about what day it is, we should conceptualise the day i that she observes as if it had been selected through some sort of randomising mechanism. we don’t need to be very specific about the nature of the sampling mechanism that we imagine. the point is simply that, in order to represent beauty’s uncertainty about what day it is, the way in which we model the problem must respect the intuition that both day and day are possible. the parameter α (respectively, β) represents the prior probability that a day randomly selected through this hypothetical mechanism is day , given that the this proposal generalises the one defended by moss ( ) (who, in turn, expands the analysis of the sleeping beauty problem presented in stalnaker ), by giving up the assumption of reducibility of de se to de dicto beliefs. due to space constraints, i do not address here some further concerns related to the choice of priors discussed by meacham ( ), though i pursue these further elsewhere. in any case, these issues do not affect the main point of this paper, that is providing a bayesian formulation of the sleeping beauty problem. this issue is separate from that of the choice of priors. an additional possibility, that i will not explore here (but that would constitute a possible extension of the representation that i give in this paper), would be to introduce imprecise probabilities and allow a set or an interval of possible values for the posterior (i thank an anonymous referee for drawing my attention to this possibility). see bovens and ferreira ( ) for a related discussion, though they do not apply it specifically to the sleeping beauty case. in the terminology of bovens and ferreira ( ), this would corresponds to different protocols through which beauty could learn the relevant pieces of information. i resist using this terminology here, as the parameters α and β do not, in themselves, constitute protocols, but they could be seen as consistent with different choices of protocols. s. milano result of the coin toss is heads (respectively, tails). in other words, α = p(d |h) and β = p(d |t ). since the experiment is expected to run over two days, regardless of the result of the coin toss, it makes sense to assume a uniform prior distribution over the two days in both scenarios (whether the coin toss comes up heads or tails). on this view, when considering what values to set for α and β, beauty employs the principle of indifference (pi, for short): since she has no reason to believe, assuming that the result of the coin toss is heads (respectively, tails) and before anything else is learned, that any one of the two experimental days is more likely to be selected than the other, she should assign them an equal probability, and therefore set α = (respectively, β = ). pi is a notoriously controversial principle, and i will not attempt to defend it here, although a consideration that might favour it in this particular instance is the fact that points in time are linearly ordered, so each day should intuitively have the same weight. but it is important to note that my application of pi is conceptually distinct from a related line of reasoning that is often applied to the sleeping beauty problem, which is known in the literature as the restricted principle of indifference (rpi, for short). according to rpi, any two events that take place within the same history (such as the awakenings on day and day , in the event of the coin toss coming up tails) and which would be subjectively indistinguishable for an agent experiencing them given some evidence e, should receive equal posterior probability after learning that e. this principle places a substantive restriction on the posterior probabilities that an agent may come to have upon a learning event, and has come under independent criticism (see marcoci , weatherson ). in contrast, pi—as i have employed it—gives us a way to set beauty’s prior probabilities, which i take to be more in line with the general commitments of bayesian reasoning (i also consider alternative ways to fix the prior parameters in sect. . ). . a numerical answer to represent beauty’s uncertainty about which day it is when she wakes up within a probabilistic framework (on the assumption that beauty reasons as a bayesian agent) we have refined the simple state space �, and then we employed the principle of indifference to generate beauty’s prior probabilities for the events that we defined relative to the refined state space �′. if we now plug in the chosen values for α and β to eqs. and from sect. , we are finally able to compute the desired probabilities: p(w ) = + = ( ) p(h|w ) = + = ( ) bayesian beauty and moreover, answering the further questions in sect. . : p(h|d ) = ( ) p(h|l) = ( ) p(w |d ) = p(w |d ) = ( ) none of the above answers seems particularly surprising. if beauty is told that it is day , she intuitively is in the same situation as someone who doesn’t (yet) know the result of a fair coin toss, and this explains why we have a strong intuition that she should assign a probability of to heads. similarly, if beauty learns that this is the last time she wakes up, but does not know if it is day or day , she knows that it is heads if and only if it is day , and tails if and only if it is day . this means that p(h|l) = p(d |l), and it is very plausible that both should equal . finally, the probabilities in eq. are simply in line with the description of the experimental setup. . tweaking the parameters although the motivations i gave to support it in sect. are different, my numerical solution to the sleeping beauty problem agrees with the one put forward by elga ( ), and which is known in the literature as the ‘thirder’ solution. however, elga’s original paper did not settle the answer to the sleeping beauty problem, as attested by a literature growing around it to this day. in this section, i review another prominent alternative solution to the sleeping beauty problem, lewisian halfing. i show how this solution too can be derived within the framework that i gave in sect. , and then critically examine a possible rationale for it. an early reply to elga by david lewis ( ) advocated a different solution to the original problem, which has come to be known as ‘halfing’. according to lewis, beauty’s credence in heads should not change between the time before she is put to sleep and when she wakes up on day , but should stay equal to . in other words, for lewis, both p(h) = and p(h|w ) = . the rationale given by lewis to defend this ‘halfer’ solution is that, upon waking up, beauty does not learn anything new. she was aware all along that she would wake up at least once during the experiment, and therefore an awakening does not give her additional clues about the outcome of the coin toss. given this consideration, halfers argue that beauty should not change her credence in heads upon waking up. since she knows the coin to be fair, she should maintain a credence of in heads. dorr ( ) also gives an argument in favour of elga’s solution based on a variation of the problem where sleeping beauty is awakened every day with her memory temporarily erased, but remembers the monday awakening after a little while on tuesday if heads. due to space constraints, i do not elaborate on this variation here, but note that dorr’s argument is different from the one presented here, as different solutions cannot be rationalised in his approach. s. milano lewis’s solution, like elga’s, can be derived within the refined state space �′ that i have given in sect. (see table ). this is because both lewis and elga agree that we need to model beauty’s uncertainty regarding what day it is, since this information is relevant to the probability of heads. they also agree that, if the coin lands tails, beauty is equally likely to wake up on day as she is on day , that is β = . however, in order to get lewis’s solution, the conditional probability of day given heads should be set equal to , that is, α = . when we set the parameters in this way, the prior probability of the event w is: p(w ) = + = ( ) and the resulting numerical solution to the sleeping beauty problem is therefore: p(h|w ) = + = ( ) the halfer solution is known to generate some counter intuitive answers when it comes to the further questions i formulated in sect. . . these can all be easily derived in the formal model i have given in sect. . one problem for the lewisian halfers is that the probability that beauty assigns to heads appears to increase if, upon awakening, she is informed that it is day , as (by eq. ): p(h|d ) = + = this result is clearly puzzling, since beauty’s awakening on day happens inde- pendently of the result of the coin toss. lewis himself acknowledged the puzzling nature of this result, arguing that it constitutes an interesting case of getting evidence ‘about the future’ (lewis , p. ). in spite of the puzzling result it generates, lewisian halfing remains a relatively popular solution. this is because it makes a basic appeal to an intuition that is shared by many people, regarding what is the content of beauty’s evidence upon waking up. the idea behind lewisian halfing is the following: if the coin toss comes up heads, beauty can only wake up on day . moreover, beauty only observes a day if she gets to wake up on that day. therefore, if heads, day is experienced with certainty. there is no possible scenario in which beauty gets to observe day , if heads, and so the prior probability assigned to day given heads should be . although it appears intuitive, this motivation for the halfer solution may rest on a misunderstanding of what is the observable event w in the sleeping beauty problem. as i explained in sect. , w contains all the outcomes of the refined state space �′ in which beauty is awake. when she is put to sleep, beauty considers it possible that another popular solution, that i will not review here, is ‘double halfing’ (see e.g. meacham ; cozic ). this solution, too, can be derived within my framework by setting α = and β = , but has the drawback of violating the third assumption from sect. (though see hawley ( ) for an argument in favour of this option). it can also be subjected to a similar ddb argument as the one for the lewisian halfer that i discuss in sect. below. bayesian beauty she will not wake up on every day during the experiment. this is because she knows that it is possible that she will sleep through day , namely if the result of the coin toss is heads. so, even though she knows that she will not be consciously aware of it if and when it happens, day given heads is a live possibility at the outset, to which she intuitively should assign a positive prior probability. if the halfer solution were correct, however, then beauty would be certain that the prior probability of w is equal to , since (plugging in α = in eq. ) p(w ) = + = . moreover, puzzlingly, she would also be certain to wake up, conditional on it being day , as we can see by solving eq. : p(w |d ) = − − − = . in other words, according to lewisian halfing, beauty would be certain that she wakes up on every day during the experiment—even though this clearly is contrary to the description of the experimental setup, which specifies that the prior probability that she wakes up on day is equal to the probability that the coin toss comes up tails—which, the coin being fair, is in turn equal to . another reason to believe that the halfer intuition may rest on a misunderstanding is that halfers often justify the value of β = on the basis of the same restricted principle of indifference advocated by elga (but which is not necessary to derive the thirder solution, as i have shown). this means that (at least in the case where the coin toss comes up tails) lewisian halfers allow for the possibility that we should think of the day beauty observes as if it were randomly selected from the set of possible days within a tails run. but why should this same reasoning not apply to the heads run, as well? after all, the indifference should reflect the ignorance of which day it is according to beauty’s priors, and not be taken as a way to set her posterior probabilities. matters of principle in this section, i examine how the proposed representation and solution tally with two principles, conditionalization and reflection, which concern the relationship between anagent’scredencesatdifferenttimes.thefactthatthethirdersolutionseemstoviolate conditionalization and reflection could be taken as indication that these principles are not necessary conditions for diachronic rationality. however, i show that the thirder solutionderivedwithinmyframeworkupholdsbothconditionalizationandreflection, when appropriately construed. . conditionalization the sleeping beauty problem is generally taken to present a challenge to the principle of conditionalization. conditionalization is the way in which bayesian reasoners are expected to update their credences over time, upon learning new pieces of information. it works like this: suppose that at time t , you learn a new piece of evidence e (and nothing else). for any event a, the probability that you assign to a at t after learning that e should be equal to the conditional probability you used to assign to (a|e) at the see titelbaum ( ), p. : ‘the current consensus in the self-locating credence literature is that obtaining a general updating scheme for degrees of belief in both centered and uncentred propositions requires us to alter (or at least supplement) conditionalization in some way.’ s. milano time t just before learning e. more formally, denoting by pt and pt your credences at t and t , respectively, conditionalization places the following constraint on how your credences should change between t and t , when the only thing that you learn in the interval between these two times is e: definition (conditionalization). pt (a) = pt (a|e) = pt (a|e) the question now is: does beauty update her credences via conditionalization upon waking up on day ? it is often argued that if beauty is a thirder, then the way her credence in heads is updated when she wakes up on day is not compatible with conditionalization. elga himself makes this point: before being put to sleep, your credence in h was / . […] when you are awakened on [day ], that credence ought to change to / . this belief change is unusual. it is not the result of your receiving new information—you were already certain that you would be awakened on [day ]. (elga , p. ) the upshot, for elga, is that conditionalization does not always apply. in cases where an agent receives only centered evidence, his or her credences may change in ways that conflict with conditionalization. in light of the analysis i have offered in sect. , we can see how elga’s argument here cannot be right. to say that the change in beauty’s credence in heads ‘is not a result of [her] receiving new information’ implies that beauty is certain that she will receive evidence w , or—more precisely—it implies that the prior probability p(w ) equals . but, as we have seen, relative to the assignment of values to α and β consistent with the thirder solution, this is not true, because for α = we have that p(w ) = �= . in other words, if she is a thirder, beauty is not certain that she always learns w . moreover, as i argued in sect. , learning w is relevant to the probability of h. the last sentence from elga’s quote indicates where the problem lies. when elga says that beauty does not receive new information, that is because she is certain of waking up on day . this explains why, intuitively, on day she is certain that she will receive evidence w at least once in the future—namely, on day . conditional on her being awake and it being day , beauty’s credence in heads should indeed remain unchanged (as i also argued in sect. ), since p(h) is independent of p(w ∩ d )— that is, p(h|w ∩ d ) = = p(h). however, upon waking up, beauty does not learn that w ∩ d . instead, her evidence is just w , and since p(h) is not independent of p(w ), this is relevant information upon which she should update her credences via conditionalization. my solution allows this, and thus vindicates conditionalization. lewis’s halfer solution—contrary to elga’s—does not entail a violation of condi- tionalization. lewis simply starts from the assumption that the evidence w is irrelevant to h, and as we have seen this can be achieved within the representation i have given by setting α = and β = . given this setting, the prior probability p(w ) = , and so beauty is indeed certain that she will receive evidence w , which then gives us p(h|w ) = = p(h), without any violations of conditionalization. based on this discussion, we can now see that the key difference between the halfer and thirder solutions is the characterisation of the event w . for halfers, w is bayesian beauty certain, and so learning w does not affect the probability of heads. for thirders, on the contrary, w is not always certain, and therefore learning it affects the probability of heads, via conditionalization. given these results, we can see that once the problem is correctly represented, the solution to the sleeping beauty problem does not challenge the validity of conditionalization as a principle for updating one’s credences in the face of newly acquired evidence. . reflection another rationality principle that appears to be violated in the sleeping beauty case is van fraassen’s reflection principle (van fraassen ). suppose that you are a rational bayesian agent, that you always plan to update your credences via condi- tionalization, and you do not expect to suffer any cognitive mishap that would lose you some of your previous evidence. then let, as before, pti denote your credences at a time ti, and ptj denote your credences at some later time t j>i. if you know, at ti, that your later credence ptj (a) in some event a will be equal to some real number ≤ p ≤ , then, intuitively, your credence at pt (a) should match that same value. that is, stated somewhat more formally (see schervish et al. ): definition (reflection). pti (a|ptj (a) = p) = p. clearly, you do not typically know what probability you will assign to an uncertain event in the future. this is because you do not generally know in advance which possible pieces of evidence you will learn in the future, and so you do not know what posterior probability you will assign to a by the time t j. however, if you were certain that you will receive a particular piece of evidence e (and nothing more) by t j, which would lead you to update your credence in a (via conditionalization) to ptj (a) = pti (a|e) = p, then it seems reasonable to suppose that you should already have the same credence pti (a) = p at the earlier time ti. this is indeed confirmed by the probability calculus: to be certain, at ti, that you will receive evidence e just means that pti (e) = , and so naturally pti (a) = pti (a|e) = p. despitethisnaturalreading,theprincipleofreflectionhascomeunderconsiderable critical scrutiny (mahtani ). the sleeping beauty problem, in particular, provides one instance where the principle of reflection appears to be violated. if beauty is a thirder, and assigns a probability of to heads upon waking up on day , it seems that her prior credences on day , before the experiment begins, violate reflection. this is because she knows, at t = day , that she will receive the evidence w at t = day . by reflection, then, it seems that her earlier credence in h at t should be pt (h|pt (h) = ) = . beauty’s credence in heads on day , however, is not equal to but to , in accordance with what she knows about the experimental setup, which explicitly sets the prior p(h) = . so, it seems that either the initial probability of heads is not , or beauty’s credences do not satisfy reflection. both alternatives seem very bad: the former flatly contradicts the setup of the problem, while the latter is inconsistent with the probability calculus, under the assumption that beauty is a rational agent who updates her credences via conditionalization. what can possibly have gone wrong? s. milano the puzzle, i think, derives from the rather informal statement of reflection, which has led us to a subtle mis-interpretation. to find the solution to the puzzle, we need only look more closely into the conditions under which beauty expects to learn w . this is because it is well-known (see mahtani ; briggs ; schervish et al. ) that a rational agent’s credences at t should not reflect her credences at a successive time t when the agent at t should not ‘trust’ her later self at t because either: . the agent expects to suffer memory loss between t and t , losing some relevant evidence; or . it is the case that both (a) at t , the agent does not know that it is t ; and (b) learning that t has arrived would give her new evidence, which would change her credences at t . we can easily verify that conditions .a and .b are both satisfied in the sleeping beauty case, hence why her credence at t is not required by reflection to match her expected credence at t . given what she knows about the experimental setup, beauty expects to receive evidence w on day , since she is certain that the experimenters wake her up on day irrespective of the coin toss. this consideration is reflected in the prior probability p(w |d ) = , as can be easily verified (see sect. ). so, when we say that beauty is certain to learn w (and, as a consequence, to update the probability of heads to p(h|w ) = ), what we really mean is that beauty is certain to experience an awakening on day . but, clearly, t is not a stopping time for beauty, since upon waking up she does not know what day it is. if at t she was in a position to conditionalize on learning w ∩ d , then indeed reflection would be satisfied, as expected: pt (h|w ∩ d ) = pt (h|w ∩ d ) = . however, beauty does not learn w ∩ d at t , but only w . this explains why her credence at t does not reflect her credence at t : that is not because she is irrational, or violates conditionalization in the way she updates her credences between these two times, but because at t she can only be certain that she learns w given d , but the latter event is not part of her evidence at t . it would be incorrect to say that pt (w ) = , since pt (w ) = . therefore, beauty is not certain of w at the earlier time, and she can’t reflect on it. notice that the same argument for why reflection does not hold in the sleeping beauty case also applies to the halfer solution, since it is also true under this solution that day is not a stopping time for beauty and, moreover, learning that it is day would lead the halfer to increase her credence in h from to . this indicates that the fact that the halfer does not change her credence in h between t and t is not due to an application reflection. bets and odds as i showed in the previous sections, both the thirder and the halfer solutions can be represented within a bayesian framework, in a way that is compatible with the prin- ciples of conditionalization and reflection. a well known result by lewis, reported by teller ( and generalised by skyrms ) shows that a bayesian agent can that is, in schervish et al. ( )’s terms, t is not a stopping time. see also lewis ( ). bayesian beauty avoid falling victim to a diachronic dutch book (ddb, for short) only if she plans to update her credences via conditionalization. a ddb, in this context, is a series of bets offered to the agent before and after she learns a given piece of evidence, such that each individual bet is fair, but when taken in combination they guarantee her a sure loss. for illustration, imagine that betty is a bayesian who plans to update her credences via conditionalization. before a fair die is rolled, we can assume that she might accept a bet x that pays £ if the die shows a , and loses £ otherwise. the expected value of this bet for betty now is , as she expects to lose £ with a probability of , and win £ with a probability of . she also currently estimates that the probability that she wins the bet, conditional on the die showing an odd number, is equal to , which is higher than her current unconditional probability of winning. so, betty would also be prepared now to accept a conditional bet y that pays £ if the die shows a , and loses £ otherwise, all conditional on the die showing an odd number (that is, the bet is void if the die shows an even number, but gives : odds on , conditional on an odd number). suppose that later, the die is rolled and betty receives the information that it shows an odd number. at that point, given that she plans to update her credences via conditionalization, she will be prepared to accept an unconditional bet z on the die showing a , at the same odds as the conditional bet y . the expected value of z, later, is the same for betty as the expected value of y now—so, if the expected value of y is non-negative, the same must be true for z. regardless of whether she is a halfer or a thirder, on the solution i have given in sect. beauty does not violate conditionalization. so, by lewis’s result, she should not be dutch bookable, just as betty would not be in the example i just gave. indeed, this solves one side of the puzzle that i identified in sect. : since, on the solution that i have proposed, thirders do not violate conditionalization (see sect. . ), this vindicates the fact that no genuine ddb against thirders has been found in the literature. what is, however, surprising is that the halfer solution should be vulnerable to a ddb—completing the puzzle that i identified in sect. . as i have shown in sect. . , the halfer solution can be derived within my framework with a choice of prior proba- bilities that assigns a value of to the parameter α. moreover, since under this prior probability assignment beauty is certain to learn the evidence w , her credences do not change upon waking up during the experiment, and she does not violate condi- tionalization. so, since they satisfy conditionalization, we would not expect halfers to be vulnerable to ddbs. but consider the following set of bets: on day , the bookie offers beauty a bet on h at even odds, that pays £ if the result of the coin toss is tails, and loses £ if heads. since beauty assigns equal probability to heads versus tails, she can accept the bet. then, every time that beauty wakes up during the experiment, the bookie offers her another bet, also at even odds, but which pays £ if heads, and loses £ if tails. again, assuming that beauty is a halfer (and so her probability for heads does not change upon waking up) she can accept these bets as well. but accepting all the bets that she is offered amounts to buying a dutch book: no matter see hitchcock ( ), bradley and leitgeb ( ), bovens and rabinowicz ( ). s. milano what the result of the coin toss, by the end of the experiment she is certain to lose £ . notice that the bookie does not need to have any more information than beauty does on each awakening to be able to offer her these bets—in fact, we can imagine that the bookie undergoes the same series of awakenings as beauty. how can we explain this? is the existence of ddbs against the halfer proof that this solution is incoherent, or does it provide a counterexample to lewis’s result, undermining a standard argument for conditionalization? given that the halfer solution can be derived within the framework i put forward in sect. , we know that this solution is probabilistically coherent, so we can dismiss the first worry. meanwhile, the second worry merits closer consideration. a crucial feature of the ddb against halfers is that it requires the possibility of an additional bet, that is placed on day only if the result of the coin toss is tails. what this means is that, in the event of tails, the book purchased by beauty contains three bets, which, as we have seen, taken together have a negative value. but the ddb considered in lewis/teller ( ) only takes into account an agent’s probability assignments at two distinct points in time, before and after learning a new piece of evidence e. in other words, let p−(a) be the probability that the agent assigns to an event a at t , and p+(a) be the probability that the agent assigns to a at ti, after learning a piece of evidence e. lewis shows that, unless p+(a) = p−(a|e), there is a ddb that can be formulated against the agent by offering her some bets at t and at ti. but even if the agent updates via conditionalization between t and ti, lewis’s result does not say anything about bets that the agent could take at some additional time t j, j �= i. so, technically, the ddb against the halfer does not constitute a counterexample to lewis’s dutch book argument for conditionalization. is this enough to get standard conditionalization off the hook? maybe not quite. while this vindicates lewis’s and skyrms’s results, the problem remains that planning to update via conditionalization is not sufficient to ensure that the agent does not commit to a series of bets that guarantee a sure loss. a way out of the impasse, discussed by briggs ( ), may be to argue that halfers should adopt evidential decision theory. but this option has several drawbacks, among others the fact that it would generate a ddb against the thirder solution (also discussed in briggs ), and that it would give unstable recommendations to the halfer under slight vari- ants of the problem (conitzer ). perhaps, then, one should bite the bullet and try to argue that only pairwise ddbs are significant means of eliciting an agent’s epistemic attitudes, while allowing ddbs to vary in length introduces strategic considerations that can influence beauty’s betting odds, as she needs to coordinate the choice she makes on the bet she is offered with the choices she would make on bets that might be offered to her at other times. ultimately, the most plausible lesson to draw from the ddb against the halfer may be that satisfying conditionalization is a necessary, but not sufficient, condition to ensure invulnerability from ddbs of varying length. if heads, beauty loses £ on the first bet on day , and wins £ on the second bet she takes on day , amounting to an overall loss of £ . if tails, beauty wins £ with the bet taken on day , but then accepts the second bet both on day and on day , each time losing £ , again amounting to an overall loss of £ . bayesian beauty conclusion the sleeping beauty problem has generated a great deal of controversy, as all the main attempts to solve it in the literature appear to violate some or other rationality constraint (titelbaum ). this creates a puzzling state of affairs, as thirder solutions are usually thought to violate the principles of conditionalization and reflection, while halfer solutions seem vulnerable to a diachronic dutch book. i have shown that it is possible to model a range of possible solutions to the sleep- ing beauty problem in a bayesian framework. all the solutions that can be derived within this framework, including the thirder solution that i have defended, respect conditionalization, thus explaining why they are not subject to lewis-style ddbs. moreover, ddbs against the halfer solution do not provide a counterexample to the claim that conditionalization is a necessary condition for diachronic rationality. i take the main lessons that can be drawn from my discussion to be the following: . bayesian reasoning can be naturally applied to self-locating uncertainty. the locus of disagreement between different solutions to the sleeping beauty problem con- cerns only the choice of priors. . in order to avoid puzzling conclusions, we should be careful to model what is the prior probability of receiving different pieces of evidence. . the case of sleeping beauty does not present a counterexample to the principles of conditionalization and reflection. it does, however, raise interesting questions with respect to whether conditionalization is sufficient to ensure invulnerability to certain types of ddbs. openaccess thisarticleislicensedunderacreativecommonsattribution . internationallicense,which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the creative commons licence, and indicate if changes were made. the images or other third party material in this article are included in the article’s creative commons licence, unless indicated otherwise in a credit line to the material. if material is not included in the article’s creative commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. to view a copy of this licence, visit http://creativecommons.org/licenses/by/ . /. references baratgin, j., & walliser, b. 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( ). the snow white problem. synthese, , – . https://doi.org/ . / s - - -x. publisher’s note springer nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. https://doi.org/ . /s - - - http://doi.org/ . /ergo. . . http://arxiv.org/abs/math/ https://doi.org/ . /ergo. . . https://doi.org/ . /ergo. . . https://doi.org/ . /s - - -x https://doi.org/ . /s - - -x bayesian beauty abstract introduction the problem . further questions . prior perspectives solution . a numerical answer . tweaking the parameters matters of principle . conditionalization . reflection bets and odds conclusion references wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ think dummy () ar x iv : . v [ he p- ex ] m ay desy– – may measurement of beauty and charm production in deep inelastic scattering at hera and measurement of the beauty-quark mass zeus collaboration abstract the production of beauty and charm quarks in ep interactions has been studied with the zeus detector at hera for exchanged four-momentum squared < q < gev using an integrated luminosity of pb− . the beauty and charm content in events with at least one jet have been extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. differential cross sections as a function of q , bjorken x, jet transverse energy and pseudorapidity were measured and compared with next-to-leading-order qcd calculations. the beauty and charm contributions to the proton structure functions were extracted from the double-differential cross section as a function of x and q . the running beauty-quark mass, mb at the scale mb, was determined from a qcd fit at next-to-leading order to hera data for the first time and found to be mb(mb) = . ± . (fit)+ . − . (mod.) + . − . (param.) + . − . (theo.) gev. http://arxiv.org/abs/ . v the zeus collaboration h. abramowicz ,u, i. abt , l. adamczyk , m. adamus , r. aggarwal ,a, s. antonelli , o. arslan , v. aushev , ,o, y. aushev ,o,p, o. bachynska , a.n. barakbaev , n. bartosik , o. behnke , j. behr , u. behrens , a. bertolin , s. bhadra , i. bloch , v. bokhonov ,o, e.g. boos , k. borras , i. brock , r. brugnera , a. bruni , b. brzozowska , p.j. bussey , a. caldwell , m. capua , c.d. catterall , j. chwastowski ,d, j. ciborowski ,x, r. ciesielski ,f , a.m. cooper-sarkar , m. corradi , f. corriveau , g. d’agostini , r.k. dementiev , r.c.e. devenish , g. dolinska , v. drugakov , s. dusini , j. ferrando , j. figiel , b. foster ,l, g. gach , a. garfagnini , a. geiser , a. gizhko , l.k. gladilin , o. gogota , yu.a. golubkov , j. grebenyuk , i. gregor , g. grzelak , o. gueta , m. guzik , w. hain , g. hartner , d. hochman , r. hori , z.a. ibrahim , y. iga , m. ishitsuka , a. iudin ,p, f. januschek , i. kadenko , s. kananov , t. kanno , u. karshon , m. kaur , p. kaur ,a, l.a. khein , d. kisielewska , r. klanner , u. klein ,g, n. kondrashova ,q, o. kononenko , ie. korol , i.a. korzhavina , a. kotański , u. kötz , n. kovalchuk ,r, h. kowalski , o. kuprash , m. kuze , b.b. levchenko , a. levy , v. libov , s. limentani , m. lisovyi , e. lobodzinska , w. lohmann , b. löhr , e. lohrmann , a. longhin ,t, d. lontkovskyi , o.yu. lukina , j. maeda ,v, i. makarenko , j. malka , j.f. martin , s. mergelmeyer , f. mohamad idris ,c, k. mujkic ,h, v. myronenko ,i, k. nagano , a. nigro , t. nobe , d. notz , r.j. nowak , k. olkiewicz , yu. onishchuk , e. paul , w. perlański ,y, h. perrey , n.s. pokrovskiy , a.s. proskuryakov ,ab, m. przybycień , a. raval , p. roloff ,j, i. rubinsky , m. ruspa , v. samojlov , d.h. saxon , m. schioppa , w.b. schmidke ,s, u. schneekloth , t. schörner-sadenius , j. schwartz , l.m. shcheglova , r. shehzadi ,aa, r. shevchenko ,p, o. shkola ,r, i. singh ,b, i.o. skillicorn , w. słomiński ,e, v. sola , a. solano , a. spiridonov ,k, l. stanco , n. stefaniuk , a. stern , t.p. stewart , p. stopa , j. sztuk-dambietz , d. szuba , j. szuba , e. tassi , t. temiraliev , k. tokushuku ,m, j. tomaszewska ,z, a. trofymov ,r, v. trusov , t. tsurugai , m. turcato , o. turkot ,i, t. tymieniecka , a. verbytskyi , o. viazlo , r. walczak , w.a.t. wan abdullah , k. wichmann ,i, m. wing ,w, g. wolf , s. yamada , y. yamazaki ,n, n. zakharchuk ,r, a.f. Żarnecki , l. zawiejski , o. zenaiev , b.o. zhautykov , n. zhmak ,o, d.s. zotkin i infn bologna, bologna, italy a university and infn bologna, bologna, italy a physikalisches institut der universität bonn, bonn, germany b panjab university, department of physics, chandigarh, india calabria university, physics department and infn, cosenza, italy a national centre for particle physics, universiti malaya, kuala lumpur, malaysia c the henryk niewodniczanski institute of nuclear physics, polish academy of sciences, krakow, poland d agh-university of science and technology, faculty of physics and applied computer science, krakow, poland d department of physics, jagellonian university, cracow, poland deutsches elektronen-synchrotron desy, hamburg, germany deutsches elektronen-synchrotron desy, zeuthen, germany school of physics and astronomy, university of glasgow, glasgow, united kingdom e hamburg university, institute of experimental physics, hamburg, germany f institute of particle and nuclear studies, kek, tsukuba, japan g institute of physics and technology of ministry of education and science of kazakhstan, almaty, kazakhstan institute for nuclear research, national academy of sciences, kyiv, ukraine department of nuclear physics, national taras shevchenko university of kyiv, kyiv, ukraine department of physics, mcgill university, montréal, québec, canada h a t h meiji gakuin university, faculty of general education, yokohama, japan g lomonosov moscow state university, skobeltsyn institute of nuclear physics, moscow, russia i max-planck-institut für physik, münchen, germany department of physics, university of oxford, oxford, united kingdom e infn padova, padova, italy a dipartimento di fisica dell’ università and infn, padova, italy a polytechnic university, tokyo, japan g dipartimento di fisica, università ‘la sapienza’ and infn, rome, italy a raymond and beverly sackler faculty of exact sciences, school of physics, tel aviv university, tel aviv, israel j department of physics, tokyo institute of technology, tokyo, japan g università di torino and infn, torino, italy a università del piemonte orientale, novara, and infn, torino, italy a ii department of physics, university of toronto, toronto, ontario, canada m s a h physics and astronomy department, university college london, london, united kingdom e faculty of physics, university of warsaw, warsaw, poland national centre for nuclear research, warsaw, poland department of particle physics and astrophysics, weizmann institute, rehovot, israel department of physics, york university, ontario, canada m j p h a supported by the italian national institute for nuclear physics (infn) b supported by the german federal ministry for education and research (bmbf), under contract no. h pdf c supported by hir grant um.c/ / /hir/ and umrg grants ru - , rp a- afr and rp b- afr from universiti malaya, and ergs grant er - a from the ministry of education, malaysia d supported by the national science centre under contract no. dec- / /m/st / e supported by the science and technology facilities council, uk f supported by the german federal ministry for education and research (bmbf), under contract no. h guf, and the sfb of the deutsche forschungsge- meinschaft (dfg) g supported by the japanese ministry of education, culture, sports, science and technology (mext) and its grants for scientific research h supported by the natural sciences and engineering research council of canada (nserc) i supported by rf presidential grant n . . for the leading scientific schools and by the russian ministry of education and science through its grant for scientific research on high energy physics j supported by the israel science foundation iii a also funded by max planck institute for physics, munich, germany b also funded by max planck institute for physics, munich, germany, now at sri guru granth sahib world university, fatehgarh sahib c also at agensi nuklear malaysia, kajang, bangi, malaysia d also at cracow university of technology, faculty of physics, mathematics and ap- plied computer science, poland e partially supported by the polish national science centre projects dec- / /b/st / and dec- / /b/st / f now at rockefeller university, new york, ny , usa g now at university of liverpool, united kingdom h also affiliated with university college london, uk i supported by the alexander von humboldt foundation j now at cern, geneva, switzerland k also at institute of theoretical and experimental physics, moscow, russia l alexander von humboldt professor; also at desy and university of oxford m also at university of tokyo, japan n now at kobe university, japan o supported by desy, germany p member of national technical university of ukraine, kyiv polytechnic institute, kyiv, ukraine q now at desy atlas group r member of national university of kyiv - mohyla academy, kyiv, ukraine s now at bnl, usa t now at lnf, frascati, italy u also at max planck institute for physics, munich, germany, external scientific mem- ber v now at tokyo metropolitan university, japan w also supported by desy x also at Łódź university, poland y member of Łódź university, poland z now at polish air force academy in deblin aa now at university of the punjab, lahore, pakistan ab deceased iv introduction the measurement of beauty and charm production in ep collisions at hera is an im- portant testing ground for perturbative quantum chromodynamics (pqcd), since the heavy-quark masses provide a hard scale that allows perturbative calculations to be made. at leading order, the dominant process for heavy-quark production at hera is boson- gluon fusion (bgf). in this process, a virtual photon emitted by the incoming electron interacts with a gluon from the proton forming a heavy quark–antiquark pair. when the negative squared four-momentum of the virtual photon, q , is large compared to the pro- ton mass, the interaction is referred to as deep inelastic scattering (dis). for heavy-quark transverse momenta comparable to the quark mass, next-to-leading-order (nlo) qcd calculations based on the dynamical generation of the massive quarks [ – ] are expected to provide reliable predictions. beauty and charm production in dis has been measured using several methods by the h [ – ] and zeus [ – ] collaborations. all but the two most recent measurements of charm production [ , ] and older data [ ] have been combined [ ]. predictions from nlo qcd describe all results reasonably well. inclusive jet cross sections in beauty and charm events are used in the analysis presented here to extract the heavy-quark contribution to the proton structure function f with high precision, and to measure related qcd parameters. for this purpose, the long lifetimes of the weakly decaying b and c hadrons, which make the reconstruction of their decay vertices possible, as well as their large masses were exploited. two discriminating variables, the significance of the reconstructed decay length and the invariant mass of the charged tracks associated with the decay vertex (secondary vertex), were used. this inclusive tagging method leads to a substantial increase in statistics with respect to previous zeus measurements. differential cross sections as a function of q , the bjorken scaling variable, x, jet transverse energy, e jet t , and pseudorapidity, η jet, were measured. they are compared to a leading- order (lo) plus parton-shower (ps) monte carlo prediction and to nlo qcd calculations. the beauty and charm contributions to the proton structure function f , denoted as f bb̄ and f cc̄ , respectively, as well as beauty and charm reduced cross sections (σ bb̄ r and σ cc̄ r , respectively) were extracted from the double-differential cross section as a function of q and x. the results are compared to previous measurements and to predictions from perturbative qcd. the running ms beauty-quark mass, mb at the scale mb, denoted mb(mb), is measured using σbb̄r , following a procedure similar to that used for a recent extraction of the charm- quark mass [ ]. this represents the first measurement of the b-quark mass using hera or any other hadron collider data. experimental set-up this analysis was performed with data taken with the zeus detector from to , when hera collided electrons with energy ee = . gev with protons of energy gev, corresponding to a centre-of-mass energy √ s = gev. this data-taking period is denoted as hera ii. the corresponding integrated luminosity is ( ± ) pb− . a detailed description of the zeus detector can be found elsewhere [ ]. a brief outline of the components that are most relevant for this analysis is given below. in the kinematic range of the analysis, charged particles were tracked in the central tracking detector (ctd) [ – ] and the microvertex detector (mvd) [ ]. these components operated in a magnetic field of . t provided by a thin superconducting solenoid. the ctd consisted of cylindrical drift-chamber layers, organised in nine superlayers covering the polar-angle region ° < θ < °. the mvd silicon tracker consisted of a barrel (bmvd) and a forward (fmvd) section. the bmvd contained three layers and provided polar-angle coverage for tracks from ° to °. the four-layer fmvd extended the polar- angle coverage in the forward region to °. after alignment, the single-hit resolution of the mvd was µm. the transverse distance of closest approach (dca) of tracks to the nominal vertex in x–y was measured to have a resolution, averaged over the azimuthal angle, of ( ⊕ /pt ) µm, with pt in gev. for ctd-mvd tracks that pass through all nine ctd superlayers, the momentum resolution was σ(pt )/pt = . pt ⊕ . ⊕ . /pt , with pt in gev. the high-resolution uranium–scintillator calorimeter (cal) [ – ] consisted of three parts: the forward (fcal), the barrel (bcal) and the rear (rcal) calorimeters. each part was subdivided transversely into towers and longitudinally into one electromagnetic section (emc) and either one (in rcal) or two (in bcal and fcal) hadronic sections (hac). the smallest subdivision of the calorimeter was called a cell. the cal energy res- olutions, as measured under test-beam conditions, were σ(e)/e = . / √ e for electrons and σ(e)/e = . / √ e for hadrons, with e in gev. the luminosity was measured using the bethe-heitler reaction ep → eγp by a luminosity detector which consisted of independent lead–scintillator calorimeter [ – ] and magnetic spectrometer [ ] systems. in this paper “electron” is used to denote both electron and positron. the zeus coordinate system is a right-handed cartesian system, with the z axis pointing in the nominal proton beam direction, referred to as the “forward direction”, and the x axis pointing towards the centre of hera. the coordinate origin is at the centre of the ctd. the pseudorapidity is defined as η = − ln ( tan θ ) , where the polar angle, θ, is measured with respect to the z axis. monte carlo simulations to evaluate the detector acceptance and to provide predictions of the signal and back- ground distributions, monte carlo (mc) samples of beauty, charm and light-flavour events were generated, corresponding to eighteen, three and one times the integrated luminos- ity of the data, respectively. the rapgap . mc program [ ] in the massive mode (mb = . gev, mc = . gev) was used to generate the beauty and charm samples, where the cteq l [ ] parameterisation for the proton parton density functions (pdfs) was used. in rapgap, lo matrix elements are combined with higher-order qcd radi- ation simulated in the leading-logarithmic approximation. higher-order qed effects are included through heracles . [ ]. light-flavour mc events were extracted from an inclusive dis sample generated with djangoh . [ ] interfaced to ariadne . [ ]. the cteq d [ ] pdfs were used and quarks were taken to be massless. fragmentation and particle decays were simulated using the jetset/pythia model [ , ]. the bowler parameterisation [ ] of the fragmentation function, as implemented in pythia [ ], was used for the heavy-flavour samples. the generated events were passed through a full simulation of the zeus detector based on geant . [ ]. the final mc events were then subjected to the same trigger requirements and processed by the same reconstruction program as the data. for the acceptance determination, the e jet t and η jet distributions in the charm mc, as well as the q distributions in both the beauty and charm mcs, were reweighted in order to give a good description of the data. the charm branching fractions and fragmentation fractions were adjusted to the world-average values [ , ]. theoretical predictions and uncertainties next-to-leading-order qcd predictions for differential cross sections were obtained from the hvqdis program [ ]. the calculations were used to extrapolate the visible cross sections to extract f bb̄ , f cc̄ , σ bb̄ r and σ cc̄ r (see section ). the calculations are based on the fixed-flavour-number scheme (ffns) in which only light flavours are present in the proton and heavy quarks are produced in the interaction [ ]. therefore, the -flavour ( -flavour) ffns variant of the zeus-s nlo qcd fit [ ] was used for the proton pdf for the predictions of the charm (beauty) cross sections. as in the pdf fit, the value of αs(mz) was set to . and the heavy-quark masses (pole masses) were set to mb = . gev and mc = . gev. the renormalisation and factorisation scales, µr and µf , were chosen to be equal and set to µr = µf = √ q + m b(c) . the systematic uncertainty on the theoretical predictions with the zeus-s pdfs were estimated by varying the quark masses and the renormalisation and factorisation scales. quark masses of mb = . and . gev, mc = . and . gev were used. the scales µr, µf were varied independently by a factor of two up and down. additionally, the experimental uncertainties of the data used in the pdf fit were propagated to the predicted cross sections. the total uncertainties were obtained by adding positive and negative changes to the cross sections in quadrature. this results in total uncertainties of – % for beauty and – % for charm. predictions were also obtained using the - and -flavour variants of the abkm nlo pdfs [ ] for the proton. the pole masses of heavy quarks were set to mb = . gev and mc = . gev, both in the pdf fit and in the hvqdis calculation. the values of αs(µr) were provided by lhapdf [ , ] to ensure that the same function was used as in the pdf fit. the renormalisation and factorisation scales were both set to µr = µf = √ q + m b(c) . the nlo qcd predictions are given for parton-level jets. these were reconstructed using the kt clustering algorithm [ ] with a radius parameter r = . in the longitudinally invariant mode [ ]. the e-recombination scheme, which produces massive jets whose four-momenta are the sum of the four-momenta of the clustered objects, was used. the parton-level cross sections were corrected for jet hadronisation effects to allow a direct comparison with the measured hadron-level cross sections: σhad, nlo = chadσparton,nlo , ( ) where the correction factors, chad = + ∆had, were derived from the rapgap mc simu- lation. the factors chad are defined as the ratio of the hadron-level jet to the parton-level jet cross sections, and the parton level is defined as the result of the parton-showering stage of the simulation. since chad were derived from an lo plus parton shower mc, but are applied to an nlo prediction, the uncertainty on chad cannot be estimated in a straightforward way. within the framework of parton showering, mc subsets with different numbers of radiated partons were investigated using rapgap and pythia samples. these studies indicated that different approaches yield variations of ∆had of typically a factor of two. since it is not clear if the variations can be interpreted as uncertainties on chad, no such uncertainties were included in the cross-section (f ) predictions. however, for the extraction of the b-quark mass, such a theoretical uncertainty needs to be included. data selection events containing a scattered electron were selected online by means of a three-level trigger system [ , ]. the trigger [ ] did not require the presence of a secondary vertex nor of a jet. offline, the scattered electron was reconstructed using an electron finder based on a neural network [ ]. the hadronic system was reconstructed from energy-flow objects (efos) [ , ] which combine the information from calorimetry and tracking, corrected for energy loss in the detector material. the kinematic variables used in the cross-section measurements, q and x, were reconstructed using the double-angle method [ ]. the following cuts were applied to select a clean dis sample: • the reconstructed scattered electron [ , ] was required to have an energy e′e > gev; • the impact position of the scattered electron on the face of the rcal had to be outside the region × cm centred on x = y = ; • the primary vertex had to be within ± cm in z of the nominal interaction point; • the photon virtuality, q , had to be within < q < gev ; • yjb > . , where yjb is the inelasticity reconstructed using the jacquet-blondel method [ ]; • ye < . , where ye is the inelasticity reconstructed using the electron method [ ]; • < (e − pz) < gev, where (e − pz) = ∑ i (ei − pz,i) and i runs over all final- state particles with energy ei and z-component of momentum pz,i; this selects fully contained neutral-current ep events for which e − pz = ee. jets were reconstructed from efos using the kt clustering algorithm [ ] as was described for parton-level jets in section . jets containing the identified scattered electron were not considered further. events were selected if they contained at least one jet within the pseudorapidity range − . < ηjet < . and with transverse energy, ejett , of e jet t = p jet t ejet pjet > ( . ) gev for beauty (charm), where ejet, pjet and p jet t are the jet energy, momentum and transverse momentum. the cut on e jet t was optimised separately for beauty and charm measure- ments. for beauty, a cut of e jet t > gev ensures a good correlation of reconstructed and hadron-level jets; for charm this cut was . gev to reduce the extrapolation uncertainties for the f cc̄ and σ cc̄ r measurements at low q . in order to reconstruct potential secondary vertices related to b- and c-hadron decays, tracks were selected if: • they had a transverse momentum pt > . gev; • the total number of hits on the track in the mvd was ≥ . each mvd layer provided two coordinate measurements. • if the track was inside the ctd acceptance, track recognition in the ctd was re- quired; the percentage of the tracks used for vertexing with no ctd hits was . %. tracks were associated with the closest jet if they fulfilled the criterion ∆r < with ∆r = √ (ηtrk − ηjet) + (φtrk − φjet) . if two or more of such tracks were associated with the jet, a candidate vertex was fitted from the selected tracks using a deterministic annealing filter [ – ]. this fit provided the vertex position and its error matrix as well as the invariant mass, mvtx, of the charged tracks associated with the reconstructed vertex. the charged-pion mass was assumed for all tracks when calculating the vertex mass. vertices with χ /ndf < , a distance from the interaction point within ± cm in the x–y plane, ± cm in the z direction, and < mvtx < gev were kept for further analysis. the mc gives a good description of the track efficiencies, except for a small fraction of tracks that are affected by hadronic interactions in the detector material between the interaction point and the ctd. efficiency corrections for this effect were determined from a study of exclusive ep → eρ p events [ ], using a special track reconstruction. the number of the pions from the ρ decay that were reconstructed in the mvd alone and had no extension in the ctd was measured. the resulting track efficiency correction in the mc was applied by randomly rejecting selected vertex tracks before the vertex fit, with a probability that depends on the track parameters (around % at η = and pt = gev). extraction of the heavy-flavour cross sections using the secondary-vertex candidates associated with jets, the decay length, d, was defined as the vector in x–y between the secondary vertex and the interaction point projected onto the jet axis in the x–y plane. the sign of the decay length was assigned using the axis of the jet to which the vertex was associated; if the decay-length vector was in the same hemisphere as the jet axis, a positive sign was assigned to it, otherwise the sign of the decay length was negative. negative decay lengths, which originate from secondary vertices reconstructed on the wrong side of the interaction point with respect to the direction of the associated jets, are unphysical and caused by detector resolution effects. a small smearing correction [ ] to the mc decay-length distribution was applied in order to reproduce the data with negative values of decay length. the beauty and charm content in the selected sample was determined using the shape of the decay-length significance distribution together with the secondary-vertex mass dis- tribution, mvtx. the decay-length significance, s, is defined as d/δd, where δd is the uncertainty on d. the invariant mass of the tracks fitted to the secondary vertex provides in the x–y plane, the interaction point was defined as the centre of the beam ellipse, determined using the average primary vertex position for groups of a few thousand events, taking into account the difference in angle between the beam direction and the z direction. the z coordinate was taken as the z position of the primary vertex of the event. a distinguishing variable for jets from b and c quarks, reflecting the different masses of the b and c hadrons. figure shows the decay-length significance, s, for e jet t > . gev divided into four bins: < mvtx < . gev, . < mvtx < gev, < mvtx < gev and no restriction on mvtx. the mc simulation provides a good description of the data. the separation into subsamples is described below. the contents of the negative bins of the significance distribution, n(s−), were subtracted from the contents of the corresponding positive bins, n(s+), yielding a subtracted decay- length significance distribution. in this way, the contribution from light-flavour quarks is minimised. an additional advantage of this subtraction is that symmetric systematic effects, which might arise from discrepancies between the data and the mc, are removed. in order to reduce the contamination of tracks originating from the primary vertex, a cut of |s| > was applied. to extract the contributions from beauty, charm and light flavours in the data sample, a binned χ fit of the subtracted significance distribution in the region < |s| < was performed simultaneously for three mass bins [ ]: < mvtx < . gev; . < mvtx < gev; < mvtx < gev. all mc distributions were normalised to the integrated luminosity of the data before the fit. the overall mc normalisation was constrained by requiring it to be consistent with the normalisation of the data in the significance distribution with |s| < and < mvtx < gev. the fit yielded scaling factors kb, kc and klf for the beauty, charm and light-flavour contributions, respectively, to obtain the best description of the data. the correlation coefficients were as follows: ρb,c = − . (− . ), ρb,lf = . ( . ) and ρc,lf = − . (− . ) for ejett > . ( . ) gev. the subtracted and fitted distributions for e jet t > . gev are shown in fig. . a good agreement between data and mc is observed. the first two mass bins corresponding to the region < mvtx < gev are dominated by charm events. in the third mass bin, beauty events are dominant at high values of significance. the fit procedure was repeated for every bin of a given observable to obtain differential cross sections. for the beauty cross-section extraction, the fit procedure was repeated with the higher cut on e jet t , e jet t > gev. control distributions of e jet t , η jet, log q and log x are shown in fig. after beauty enrichment cuts ( < mvtx < gev and |s| > ) for ejett > . gev and in fig. after charm enrichment cuts ( < mvtx < gev and |s| > ) for ejett > . gev. all data distributions are reasonably well described by the mc. the differential cross sections for jet production in beauty or charm events, q = b, c, corrected to qed born level, in a bin i of a given observable, y , are given by: dσjetq dyi = kq(yi) nhad,mcq (yi) l · ∆yi crad , ( ) where ∆yi is the width of the bin, kq denotes the scaling factor obtained from the fit, nhad,mcq is the number of generated jets in beauty or charm events at the mc hadron level, crad is the qed radiative correction and l is the corresponding integrated luminosity. hadron-level jets were obtained by running the kt clustering algorithm on all stable final- state particles, in the same mode as for the data. weakly decaying b and c hadrons were treated as stable particles and were decayed only after the application of the jet algorithm. the predictions from the hvqdis program are given at the qed born level with a running coupling, αem. hence, a correction of the measured cross sections for qed radiative effects is necessary in order to be able to compare them directly to the hvqdis predictions. the corrections were obtained using the rapgap monte carlo as crad = σrad/σborn, where σrad is the cross section with full qed corrections, as used in the standard mc samples, and σborn was obtained with the qed corrections turned off but keeping αem running. both cross sections, σrad and σborn, were obtained at the hadron level. systematic uncertainties the systematic uncertainties were evaluated by varying the analysis procedure or by chan- ging the selection cuts and repeating the extraction of the cross section. the following sources of experimental systematic uncertainties were identified [ , ]; the uncertainties on the integrated cross sections determined for each source are summarised in table to indicate the sizes of the different effects: δ dis selection – the cuts for dis event selection were varied in both data and mc. the cut on the scattered electron energy was varied between < e′e < gev (δ ee ), the cut on the inelasticity was varied between . < yjb < . (δ y ), and the lower cut on e − pz was changed by ± gev (δe−pz ); δ trigger efficiency – the uncertainty on the trigger efficiency was evaluated by comparing events taken with independent triggers; δ tracking efficiency correction – the size of the correction was varied by its estimated uncertainty of ± %; δ decay-length smearing – the fraction of secondary vertices for which the decay length was smeared was varied separately in the core (δcore ) and the tails (δ tail ) of the distri- bution such that the agreement between data and mc remained reasonable; δ signal extraction procedure – the systematic uncertainty on the signal extraction pro- cedure was estimated by changing the lower |s| cut from |s| > to |s| > and |s| > ; δ jet energy scale – the calorimetric part of the transverse jet energy in the mc was varied by its estimated uncertainty of ± %; δ electron energy scale – the reconstructed energy of the scattered electron was varied in the mc by its estimated uncertainty of ± %; δ mc model dependence – the q (δ q ), η jet (δ ηjet ) and e jet t (δ e jet t ) reweighting corrections in the charm mc were varied in a range for which the description of data by mc remained reasonable. the same relative variations were applied to the beauty mc; δ light-flavour background – the light-flavour contribution to the subtracted significance distribution includes a contribution from long-lifetime strange-hadron decays. to es- timate the uncertainty due to modelling of this effect, the mc light-flavour distribution of n(s+) − n(s−) was scaled by ± % [ ] and the fit was repeated; δ charm fragmentation function – to estimate the sensitivity to the charm fragmentation function, it was changed in the mc from the bowler to the peterson [ ] parameterisa- tion with ǫ = . [ ]; δ beauty fragmentation function – to estimate the sensitivity to the beauty fragmentation function, it was changed in the mc from the bowler to the peterson parameterisation with ǫ = . [ ]; δ charm branching fractions (δ br ) and fragmentation fractions (δ frag ) – these were varied within the uncertainties of the world-average values [ , , ]; δ luminosity measurement – a . % overall normalisation uncertainty was associated with the luminosity measurement. to evaluate the total systematic uncertainty on the integrated cross sections, the contri- butions from the different systematic uncertainties were added in quadrature, separately for the negative and the positive variations. the same procedure was applied to each bin for the differential cross sections. however, the luminosity measurement uncertainty was not included. in the case of beauty, the dominant effects arise from the uncertainties on the track-finding inefficiencies, the beauty fragmentation function and mc modelling. for charm, the uncertainties on the branching fractions, the light-flavour asymmetry as well as on the mc modelling contribute most to the total systematic uncertainty. cross sections cross sections for inclusive jet production in beauty (charm) events were measured in the range e jet t > ( . ) gev, − . < ηjet < . for dis events with < q < gev and . < y < . , where the jets are defined as in section . the single-differential cross sections for jet production in beauty and charm events were measured as a function of e jet t , η jet, q and x. the results of the measured cross sections are given in tables – and shown in figs. – . the measurements are compared to the hvqdis nlo qcd predictions obtained using zeus-s and abkm as proton pdfs, and to the rapgap predictions scaled by a factor of . for beauty and . for charm. the scale factors correspond to the ratio of the measured integrated visible cross section to the rapgap prediction. the shapes of all measured beauty cross sections are reasonably well described by hvqdis and the rapgap mc. rapgap provides a worse description of the shape of the charm cross sections than hvqdis. for charm, the data are typically – % above the hvqdis nlo prediction, but in reasonable agreement within uncertainties. differences between the nlo predictions using the different proton pdfs are mostly very small. double-differential cross sections as a function of x for different ranges of q for inclusive jet production in beauty and charm events are listed in tables and , respectively. extraction of f qq̄ and σqq̄ r the heavy-quark contribution to the proton structure function f , f qq̄ with q = b, c, can be defined in terms of the inclusive double-differential cross section as a function of x and q , d σqq̄ dx dq = πα em xq { [ + ( − y )]f qq̄ (x, q ) − y f qq̄ l (x, q ) } , where f qq̄ l is the heavy-quark contribution to the structure function fl. to extract f qq̄ from the visible jet production cross sections in heavy-quark events, meas- ured in bins of x and q , an extrapolation from the measured range in e jet t and η jet to the full kinematic phase space was performed. this implicitly takes into account the jet multiplicity. the measured values of f qq̄ at a reference point in the x–q plane were calculated using f qq̄ (x, q ) = d σjetq /dx dq d σ had,nlo q /dx dq f qq̄,nlo (x, q ) , ( ) where d σjetq /dx dq is determined in analogy to eq. ( ), and f qq̄,nlo and d σhad,nloq /dx dq were calculated at nlo in the ffns using the hvqdis program with the factor chad applied as in eq. ( ). the proton pdfs were obtained from the ffns variant of the herapdf . nlo qcd fit [ ]. this pdf was used in order to be consistent with the hera combined results [ ]. the strong coupling constant αs(mz) was set to . as in the pdf fit. other settings were as described in section for the zeus-s variant. as discussed in section , d σjetq /dx dq was multiplied by /cradq , hence f qq̄ is given at qed born level, consistent with the usual convention. the procedure of eq. ( ) also corrects for the f qq̄ l contribution to the cross section. this assumes that the calculation correctly predicts the ratio f qq̄ l /f qq̄ . for the acceptance corrections, the monte carlo was reweighted as discussed in section . the extrapolation factors for beauty due to cuts on e jet t and η jet typically range from . to . , decreasing with increasing q . the factor is up to . at high values of x. for charm, the extrapolation factors are typically about in the region < q < gev and about in the region < q < gev . the uncertainty on the extrapolation from the measured range to the full kinematic phase space was estimated by varying the paramet- ers of the calculation for the extrapolation factors and adding the resulting uncertainties in quadrature. for charm, the same variations were performed as for the hera com- bined results [ ]: the charm mass was varied by ± . gev; the strong coupling constant αs(mz) was changed by ± . ; renormalisation and factorisation scales were multiplied simultaneously by . or . uncertainties resulting from the proton pdf uncertainty are small [ ] and were neglected. for beauty, the same variations of αs and scales were made and the beauty mass was varied by ± . gev. for each bin, a reference point in x and q was defined (see table ) to calculate the structure function. in addition, beauty and charm reduced cross sections were determined. they are defined as σqq̄r = d σqq̄ dx dq · xq πα em[ + ( − y )] = f qq̄ (x, q ) − y + ( − y ) f qq̄ l (x, q ) , and are extracted in analogy to f qq̄ as described above except that no assumption on f qq̄ l is required. the extracted values of f bb̄ and f cc̄ are given in tables and , respectively, while σ bb̄ r and σcc̄r are shown in tables and . the total uncertainties of the measurements were calculated from the statistical and systematic uncertainties of the measured cross sections (tables , , – ) and of the extrapolation uncertainty (tables – ), added in quadrature. the structure function f cc̄ is shown in fig. as a function of x for different values of q . the measurements are compared to the nlo qcd herapdf . [ ] predictions, the most recent official release of the herapdf, based on the rt [ ] general-mass variable- flavour-number scheme (gmvfns). the predictions are consistent with the measure- ments. in fig. , the measured σcc̄r values are compared to the hera combined results [ ] as well as to the two recent results from zeus [ , ] which are not yet included in the combination. for the comparison, some of the measured values of this analysis were swum in q and x using hvqdis. this measurement is competitive, especially at high q , where the extrapolation uncertainty is low, and is in agreement with the hera combined measurements. the structure function f bb̄ is shown in fig. as a function of x for different values of q . the measurements are compared to herapdf . gmvfns predictions. the increase in the uncertainty on the prediction around q = m b is a feature of the gmvfns scheme used. the predictions are consistent with the measurements. the f bb̄ measurement is also shown as a function of q for fixed x in fig. , and is compared to previous zeus and h measurements. again, hvqdis was used to swim the measured values in q and x to match the previous measurements. in a wide range of q , this measurement represents the most precise determination of f bb̄ at hera. it is in good agreement with the previous zeus analyses and h measurements. several nlo and nnlo qcd predictions based on the fixed- or variable-flavour-number schemes [ – ] are also compared to the measurements. predictions from different theoretical approaches agree well with each other. all predictions provide a reasonable description of the data. measurement of the running beauty-quark mass the reduced beauty cross sections, σbb̄r , (fig. and table ) together with inclusive dis data were used to determine the beauty-quark mass, in a simultaneous fit of the mass and the parton densities. the measurement procedure follows closely the method presented in a recent h -zeus publication [ ], where the running charm-quark mass in the ms scheme was extracted using a simultaneous qcd fit of the combined hera i inclusive dis data [ ] and the hera combined charm dis data [ ]. this approach was also used and extended by a similar independent analysis [ ], and was preceded by a similar analysis of a partial charm data set [ ]. the fit for the running beauty-quark mass was performed within the herafitter [ ] framework choosing the abm implementation of the fixed-flavour-number scheme at next- to-leading order [ , , , , ]. the openqcdrad [ ] option in herafitter was used in the ms running-mass mode. the fit was applied to the beauty data listed in table and to the same inclusive dis data as in the charm-quark mass fit [ ]. a fit to the inclusive data only does not show any significant dependence on mb. in order to avoid technical complications, no charm data were included in the simultaneous fit and only mb was extracted. the pdfs resulting from the simultaneous fit changed only marginally with respect to the nominal pdfs obtained from the fit to the inclusive dis data only. the χ of the qcd fit, including the beauty data, shows a clear dependence on the beauty-quark mass, mb, as can be seen in fig. . the total χ for the best fit is for degrees of freedom, and the partial contribution from the beauty data is . for points. the beauty-quark mass and its uncertainty are determined from a parabolic parameterisation. the best fit yields mb(mb) = . ± . (fit)+ . − . (mod.)+ . − . (param.) + . − . (theo.) gev for the ms running beauty-quark mass at nlo. the fit uncertainty (fit) is determined from ∆χ = . it contains the experimental uncertainties, the extrapolation uncertainties, the uncertainties of the standard pdf parameterisation, as well as an estimate of the uncertainty on the hadronisation corrections, as detailed below. in addition, the result has uncertainties attributed to the choices of some extra model parameters (mod.), some additional variations of the pdf parameterisation (param.) and uncertainties on the perturbative qcd parameters (theo.). details of the uncertainty evaluation include: fit uncertainty: for the beauty data, all uncertainties from tables , (experimental) and (extrapolation), and the statistical uncertainty, as summarised in table , were accounted for in the fit. following the discussion in section , an uncertainty of % on ∆had = chad − (table ) was introduced as an additional uncorrelated uncertainty. the uncertainties arising from the default pdf parameterisation [ ], including the so-called “flexible” gluon parameterisation, are implicitly part of the fit uncertainty. the statistical uncertainties and the uncertainties δ , δ , δ core , δ and δ from tables and were treated as uncorrelated, while all other uncertainties, including those from luminosity and from table , were treated as point-to-point correlated. the “multiplicative” uncertainty option [ ] from herafitter was used. in the case of asymmetric uncertainties, the larger was used in both directions. the uncertainties of the inclusive data were used as published. since the inclusive data were taken during the hera i phase and the beauty data during the hera ii phase, the two sets of data were treated as uncorrelated. model uncertainty: the model choices include an assumption on the strangeness frac- tion, fs, the minimum q used in the data selection, q min, and q , the starting value for the qcd evolution. these were treated exactly as in the charm-quark mass fit [ ]. table lists the choices and variations and their individual contribu- tions to the model uncertainty attributed to the model choices. another source of uncertainty is that the b-quark mass was used earlier to extrapolate the measured visible cross sections to the reduced cross sections. the corresponding uncertainty is parameterised in table and used in the fit, but the correlation of this uncertainty with the mass used in the qcd fit is lost. since the hvqdis [ ] program used for the extrapolation uses the pole-mass scheme, and no differential calculations are available in the running-mass scheme, no fully consistent treatment of this correlation is possible. however, the equivalent uncertainty when using the pole-mass scheme can be consistently estimated. for this purpose, the fit was re- peated with the pole-mass option of openqcdrad, which was checked to yield results consistent with the hvqdis predictions for σbb̄r . for the charm-quark mass fit [ ] this uncertainty was denoted “exp”. the result, mb(pole) = . ± . (fit) gev, has a fit uncertainty which is the same as the fit uncertainty for the running-mass fit. however, since the pole-mass defin- ition includes an unavoidable additional theoretical uncertainty due to a nonper- turbative contribution, no attempt to extract a pole-mass measurement with full systematic uncertainties was made. to recover the correlation between the extra- polation and the mass fit, the extrapolated cross sections were iteratively modified using the predictions from the mass values obtained in each fit. this removes the uncertainty on mb in the extrapolation and takes the full correlations into account. the resulting mass mb(pole) = . ± . (fit) gev is slightly lower. the difference between the results from the two procedures (δmext = − . gev) was treated as an additional model uncertainty. pdf parameterisation uncertainty: the parameterisation of the pdfs is chosen as for the charm-quark mass fit [ ], including the “flexible” parameterisation of the gluon distribution. an additional uncertainty is estimated by freeing three extra pdf parameters duv , dd̄ and dū in the fit which allow for small shape variations in the uv, ū and d̄ parton distributions [ ]. the effect is given in table . perturbative scheme and related theory uncertainty: the parameters used for the per- turbative part of the qcd calculations also introduce uncertainties; the effects are listed in table . as in previous analyses [ , , ], the ms running-mass scheme [ – ] was chosen for all calculations of the reduced cross sections and the fit because it shows better perturbative convergence behaviour than the pole-mass scheme. in order to allow the low-q points of the inclusive dis measurement to be included without the need of additional charm-quark mass corrections, the number of active flavours (nf) was set to three, i.e. the charm contribution was also treated in the fixed-flavour-number scheme. accordingly, the strong coupling constant was set to αs(mz) nf= = . ± . , corresponding to αs(mz)nf= = . ± . . the theoretical prediction of the charm contribution to the inclusive dis data is obtained using the running charm-quark mass obtained from the fit to the combined hera charm data [ ], i.e. mc(mc) = ( . ± . ) gev. it was checked that, as expected, using this mass together with the central pdf from the mb fit, a good description of the combined hera charm data [ ] was obtained. thus, the charm contribution to the inclusive data should be well described. the renormalisation and factorisation scales were set to µ = µr = µf = √ q + m with m = , mc, mb for the light quark, charm, and beauty contributions, respect- ively, and varied simultaneously by a factor two as in previous analyses [ , ]. the measured beauty-quark mass is in very good agreement with the world average mb(mb) = ( . ± . ) gev [ ]. the resulting predictions for the beauty cross sec- tions are shown together with the data in fig. . figure also shows the change in the predictions resulting from the fit when different mb values are assumed. the largest sensit- ivity to mb arises from the low-q region, while at high q the impact of the beauty-quark mass is small. conclusions inclusive jet production cross sections in events containing beauty or charm quarks have been measured in dis at hera, exploiting the long lifetimes and large masses of b and c hadrons. in contrast to previous analyses at zeus, the measurement was not restricted to any particular final state. this resulted in substantially increased statistics. differential cross sections as functions of e jet t , η jet, q and x were determined. next-to- leading-order qcd predictions calculated using the hvqdis program using two different sets of proton pdfs are consistent with the measurements. the heavy-quark contributions to the proton structure function f as well as beauty and charm reduced cross sections were extracted from the double-differential cross sections as a function of x and q . the f bb̄ , f cc̄ and σ bb̄ r , σ cc̄ r values are in agreement with previous measurements at hera. the results were also compared to several nlo and nnlo qcd calculations, which provide a good description of the data. the precision of the f cc̄ measurement is competitive with other analyses. for a wide range of q , the f bb̄ measurement represents the most precise determination of f bb̄ . the running beauty-quark mass in the ms scheme was determined from an nlo qcd fit in the fixed-flavour-number scheme to the σbb̄r cross sections from this analysis and to hera i inclusive dis data: mb(mb) = . ± . 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[ ] particle data group, j. beringer et al., review of particle physics, phys. rev. d ( ) . http://projects.hepforge.org/herafitter http://dx.doi.org/ . /j.physletb. . . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://www-zeuthen.desy.de/~alekhin/openqcdrad http://dx.doi.org/ . /bf http://dx.doi.org/ . /s - ( ) - http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /s - ( ) - http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /physrevd. . source beauty charm (%) (%) δ event and dis selection ± . ± . δ trigger efficiency + . + . δ tracking efficiency ± . ± . δ decay-length smearing ± . ± . δ signal extraction procedure ± . ± . δ jet energy scale ± . ± . δ em energy scale ± . ± . δ charm q reweighting (δ q ,c ) ± . ± . beauty q reweighting (δ q ,b ) ± . ± . charm ηjet reweighting (δ ηjet,c ) + . − . + . − . beauty ηjet reweighting (δ ηjet,b ) + . − . + . − . charm e jet t reweighting (δ e jet t ,c ) + . − . + . − . beauty e jet t reweighting (δ e jet t ,b ) + . − . + . − . δ light-flavour asymmetry ± . ± . δ charm fragmentation function − . + . δ beauty fragmentation function − . + . δ br and fragmentation fractions + . − . + . − . δ luminosity measurement ± . ± . total + . − . + . − . table : effects of the systematic uncertainties on the integrated beauty- and charm-jet cross sections. e jet t dσ jet b /de jet t (pb/gev) c had crad (gev) stat. syst. : ± + − . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . e jet t dσ jet c /de jet t (pb/gev) c had crad (gev) stat. syst. . : ± + − . . : ± + − . . : ± + − . . : . ± . + − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of e jet t . the beauty (charm) cross sections are given for < q < gev , . < y < . , e jet t > ( . ) gev and − . < ηjet < . . the measurements are given together with their statistical and systematic uncertainties. hadronisation and qed radiative corrections, chad and crad, respectively, are also shown. ηjet dσ jet b /dηjet (pb) chad crad stat. syst. − . : − . ± + − . . − . : − . ± + − . . − . : − . ± + − . . − . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . ηjet dσjetc /dη jet (pb) chad crad stat. syst. − . : − . ± + − . . − . : − . ± + − . . − . : − . ± + − . . − . : − . ± + − . . − . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of ηjet. for details, see the caption of table . q dσ jet b /dq (pb/gev ) chad crad (gev ) stat. syst. : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . q dσjetc /dq (pb/gev ) chad crad (gev ) stat. syst. : ± + − . . : ± + − . . : ± . + − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of q . for details, see the caption of table . x dσ jet b /dx (pb) chad crad stat. syst. . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . x dσjetc /dx (pb) c had crad stat. syst. . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of x. for details, see the caption of table . q x d σ jet b /dx dq (pb/gev ) chad crad (gev ) stat. syst. : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . table : double-differential cross sections for inclusive jet production in beauty events as a function of x for different ranges of q . the cross sections are given for < q < gev , . < y < . , e jet t > gev and − . < ηjet < . . the measurements are given together with their statistical and systematic uncertainties. hadronisation and qed radiative corrections, chad and crad, respectively, are also shown. q x d σjetc /dx dq (pb/gev ) chad crad (gev ) stat. syst. : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . table : double-differential cross sections for inclusive jet production in charm events as a function of x for different ranges of q . the cross sections are given for < q < gev , . < y < . , e jet t > . gev and − . < ηjet < . . the measurements are given together with their statistical and systematic uncertainties. hadronisation and qed radiative corrections, chad and crad, respectively, are also shown. q x f bb̄ (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : the structure function f bb̄ as a function of x for seven different values of q . the first error is statistical, the second systematic and the last is the extrapolation uncer- tainty. the horizontal lines correspond to the bins in q in table . q x f cc̄ (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : the structure function f cc̄ as a function of x for seven different values of q . the first error is statistical, the second systematic and the last is the extrapolation uncer- tainty. the horizontal lines correspond to the bins in q in table . q x σbb̄r (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : reduced beauty cross sections, σbb̄r , as a function of x for seven different values of q . for more details, see the caption of table . q x σcc̄r (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : reduced charm cross section, σcc̄r , as a function of x for seven different values of q . for more details, see the caption of table . q x δ ee δ y δ e−pz δ δ δ core δtail δ δ δ ( gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . + . − . + . − . + . − . + . + . − . + . − . − . + . − . + . + . − . − . + . : . : . + . − . − . + . − . + . + . + . − . − . + . − . + . − . + . + . − . − . + . : . : . − . + . + . − . + . − . + . − . + . − . + . + . − . − . + . + . − . − . + . : . : . − . + . − . + . + . − . + . + . − . − . + . − . + . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . + . − . + . − . − . + . − . + . − . + . − . + . : . : . − . + . + . − . − . + . + . + . − . + . − . − . + . + . − . + . − . − . + . : . : . − . + . − . + . − . + . + . + . − . + . − . − . + . + . − . + . − . + . − . : . : . − . + . − . + . + . − . + . + . − . − . + . − . + . + . − . + . − . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . + . − . + . − . + . − . − . + . : . : . + . − . − . + . + . − . + . + . − . + . − . + . − . − . + . − . + . + . − . : . : . − . + . + . − . + . − . + . + . − . − . + . − . + . − . + . + . − . − . + . : . : . − . + . + . − . − . + . − . + . − . − . + . + . − . + . − . + . − . − . + . : . : . − . + . + . − . − . + . + . + . − . − . + . − . + . − . + . + . − . + . − . : . : . − . + . + . − . + . − . + . + . − . − . + . − . + . − . + . + . − . − . + . : . : . − . + . − . + . + . − . + . + . − . + . − . − . + . + . − . + . − . − . + . : . : . + . − . + . − . + . − . + . + . − . − . + . + . − . − . + . − . + . + . − . : . : . − . + . − . + . − . + . + . + . − . − . + . − . + . − . + . + . − . + . − . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in beauty events. see section for more details. q x δ q ,c δ q ,b δ η jet ,c δ η jet ,b δ e jet t ,c δ e jet t ,b δ δ δ δ br δ frag (gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . − . + . + . − . + . − . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . − . + . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . − . + . − . + . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . − . + . − . + . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . − . + . − . + . + . − . − . + . − . + . − . + . + . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . − . + . − . + . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . + . − . + . − . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . − . + . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in beauty events (continued). q x δ ee δ y δ e−pz δ δ δ core δtail δ δ δ ( gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . + . − . + . − . − . + . + . + . − . − . + . + . − . + . − . − . + . − . + . : . : . + . − . + . − . − . + . + . + . − . − . + . + . − . + . − . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . − . + . − . + . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . + . − . − . + . − . + . − . + . : . : . + . − . + . − . + . − . + . − . + . − . + . + . − . − . + . − . + . − . + . : . : . − . + . − . + . − . + . + . + . − . − . + . + . − . + . − . − . + . + . − . : . : . − . + . − . + . − . + . + . + . − . − . + . − . + . − . + . − . + . − . + . : . : . − . + . + . − . − . + . + . + . − . − . + . − . + . − . + . − . + . − . + . : . : . + . − . − . + . + . − . + . + . − . − . + . + . − . − . + . − . + . − . + . : . : . − . + . − . + . + . − . + . + . − . − . + . − . + . + . − . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . − . + . + . − . − . + . + . − . : . : . − . + . − . + . + . − . + . − . + . − . + . + . − . − . + . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . + . − . + . − . − . + . + . − . : . : . − . + . + . − . + . − . + . + . − . − . + . + . − . + . − . − . + . − . + . : . : . − . + . + . − . − . + . + . − . + . − . + . + . − . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . + . − . − . + . + . − . + . − . + . − . − . + . : . : . − . + . + . − . + . − . + . + . − . − . + . − . + . − . + . + . − . + . − . : . : . − . + . + . − . − . + . + . + . − . + . − . + . − . − . + . − . + . − . + . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in charm events. see section for more details. q x δ q ,c δ q ,b δ η jet ,c δ η jet ,b δ e jet t ,c δ e jet t ,b δ δ δ δ br δ frag ( gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . + . − . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . + . − . − . + . − . + . + . − . + . − . : . : . + . − . + . − . + . − . + . − . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . − . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . − . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . − . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . + . − . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . + . − . − . + . + . − . − . + . + . + . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . + . − . − . + . + . − . − . + . − . + . + . − . − . + . − . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . + . − . + . − . − . + . + . + . + . − . + . − . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in charm events (continued). q x δ−mb δ + mb δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . + . − . − . − . . + . − . + . − . − . − . . + . − . + . − . − . − . . + . − . − . − . + . − . . + . − . − . − . + . + . . + . − . + . − . − . − . . + . − . − . − . + . − . . + . − . + . − . + . + . . + . + . + . − . + . − . . + . − . + . − . + . − . . + . + . + . − . + . + . table : extrapolation uncertainties on the structure function f bb̄ due to the variations of the beauty-quark mass, mb, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (down- ward) variation of the corresponding parameter. see section for more details. q x δ−mc δ + mc δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . − . − . + . . + . − . + . − . − . − . . + . + . + . + . + . + . . + . − . − . + . + . + . . + . − . − . − . − . − . . + . − . − . − . − . − . . − . − . − . − . − . − . . + . − . − . + . − . − . . + . − . + . + . − . − . . − . + . + . + . − . + . . + . − . − . + . + . + . . + . + . + . − . + . + . table : extrapolation uncertainties on the structure function f cc̄ due to the variations of the charm-quark mass, mc, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (down- ward) variation of the corresponding parameter. see section for more details. q x δ−mb δ + mb δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . + . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . + . − . − . − . . + . − . + . − . + . − . . + . − . + . − . − . − . . + . − . − . − . + . − . . + . − . − . − . + . + . . + . − . + . − . + . + . . + . − . − . − . + . − . . + . − . + . − . − . + . . + . − . + . − . + . − . . + . − . + . − . + . − . . + . + . + . − . + . + . table : extrapolation uncertainties on the reduced beauty cross section, σbb̄r , due to the variations of the beauty-quark mass, mb, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (downward) variation of the corresponding parameter. see section for more details. q x δ−mc δ + mc δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . − . − . + . . + . − . + . − . + . + . . + . + . + . + . + . + . . + . − . − . + . + . + . . + . − . − . − . − . − . . + . − . − . − . − . − . . − . − . − . − . − . − . . + . − . − . + . − . − . . + . − . + . − . − . − . . − . + . + . − . + . + . . + . − . − . + . + . + . . + . + . + . − . + . + . table : extrapolation uncertainties on the reduced charm cross section, σcc̄r , due to the variations of the charm-quark mass, mc, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (downward) variation of the corresponding parameter. see section for more details. parameter variation uncertainty (gev) fit uncertainty total ∆χ = + . − . model uncertainty fs . + . − . + . − . q min . → . gev + . − . q . → . gev + . − . δmext see text − . total + . − . pdf parameterisation uncertainty duv free in fit + . dd̄ free in fit + . dū free in fit + . total + . − . theory uncertainty mc(mc) ( . ± . ) gev + . − . αs . ± . + . − . µ × , × / + . − . total + . − . table : list of uncertainties for the beauty-quark mass determination. a description of the uncertainties not explicitly mentioned in the text is given elsewhere [ ]. s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s zeus < . gevvtx < m < gevvtx . < m < gevvtx < m vtxno restriction on m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distributions of the decay-length significance, s, for (a) < mvtx < . gev, (b) . < mvtx < gev, (c) < mvtx < gev and (d) no restriction on mvtx. the data are compared to the sum of all mc distributions as well as the individual contributions from the beauty, charm and light-flavour (lf) mc subsamples. all samples were normalised according to the scaling factors obtained from the fit (see text). |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s zeus < . gevvtx < m < gevvtx . < m < gevvtx < m vtxno restriction on m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distribution of the subtracted decay-length significance in four ranges of mvtx. for more details, see the caption of fig. . (gev) jet te e n tr ie s (gev) jet te e n tr ie s jetη - . - - . . . . e n tr ie s jetη - . - - . . . . e n tr ie s ) /gev (q log . . . e n tr ie s ) /gev (q log . . . e n tr ie s x log - . - - . - - . - - . - e n tr ie s x log - . - - . - - . - - . - e n tr ie s zeus < gev, |s|> vtx < m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distributions of (a) e jet t , (b) η jet, (c) log q and (d) log x of the selected secondary vertices for a beauty-enriched subsample with < mvtx < gev and |s| > . for more details, see the caption of fig. . (gev) jet te e n tr ie s (gev) jet te e n tr ie s jetη - . - - . . . . e n tr ie s jetη - . - - . . . . e n tr ie s ) /gev (q log . . . e n tr ie s ) /gev (q log . . . e n tr ie s x log - . - - . - - . - - . - e n tr ie s x log - . - - . - - . - - . - e n tr ie s zeus < gev, |s|> vtx < m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distributions of (a) e jet t , (b) η jet, (c) log q and (d) log x of the selected secondary vertices for a charm-enriched subsample with < mvtx < gev and |s| > . for more details, see the caption of fig. . (gev) jet te ( p b / g e v ) je t t / d e σ d - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep (gev) jet te d a ta / h v q d is . . (gev) jet te ( p b / g e v ) je t t / d e σ d - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep (gev) jet te d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of e jet t . the cross sections are given for < q < gev , . < y < . , e jet t > ( . ) gev and − . < ηjet < . . the data are shown as points. the inner error bars are the statistical uncertainties, while the outer error bars show the statistical and systematic uncertainties added in quadrature. the solid line shows the hvqdis prediction with the zeus-s pdf, corrected for hadronisation effects, with the uncertainties indicated by the band; the dotted line shows the same prediction using the abkm pdf; the dashed line shows the prediction from rapgap scaled to match the measured integrated cross sections. jetη - . - - . . . ( p b ) je t η / d σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep jetη - . - - . . . d a ta / h v q d is . . jetη - . - - . . . ( p b ) je t η / d σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep jetη - . - - . . . d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of ηjet. for more details, see the caption of fig. . ) (gev q ) ( p b / g e v / d q σ d - - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep ) (gev q d a ta / h v q d is . . ) (gev q ) ( p b / g e v / d q σ d - - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep ) (gev q d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of q . for more details, see the caption of fig. . x - - - - / d x ( p b ) σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep x - - - - d a ta / h v q d is . . x - - - - / d x ( p b ) σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep x - - - - d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of x. for more details, see the caption of fig. . . . . . . . . . . . . . . . . . . . . . . x - - - - x - - - - x - - - - c c f . . . . . . . . . - zeus pb herapdf . gmvfns zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : the structure function f cc̄ (filled symbols) as a function of x for seven differ- ent values of q . the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrat- ure. also shown are the nlo qcd herapdf . predictions based on the general-mass variable-flavour-number scheme (solid line and shaded area for the uncertainties). . . . . . . . . . . . . . . . . . . . . . x - - - x - - - x - - - c c r σ . . . . . . . . . zeus = gev q = gev q = gev q = gev q = gev q = gev q = gev q - zeus vtx pb - zeus d* pb - pb+zeus d hera figure : reduced charm cross section, σcc̄r , as a function of x for fixed values of q . results from the current analysis (filled circles) are compared to the zeus d∗± data [ ] (empty triangles), the zeus d+ measurement [ ] (empty squares) and the combination of previous hera results [ ] (empty circles). the inner error bars in the zeus measure- ments show the statistical uncertainties. the inner error bars of the combined hera data represent the uncorrelated part of the uncertainty. the outer error bars include statistical, systematic and theoretical uncertainties added in quadrature. . . . . . . . . . . . . . . . . . x - - - - x - - - - x - - - - b b f . . . . . . . - zeus pb herapdf . gmvfns zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : the structure function f bb̄ (filled symbols) as a function of x for seven differ- ent values of q . the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrat- ure. also shown are the nlo qcd herapdf . predictions based on the general-mass variable-flavour-number scheme (solid line and shaded area for the uncertainties). ) (gev q + . i b b f . . . . . . . . . . . - zeus vtx pb - zeus e pb - pbµzeus - +vtx pbµzeus - h vtx pb herapdf . abkm nnlo mstw nlo mstw nnlo cteq . nlo jr x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= figure : the structure function f bb̄ (filled circles) as a function of q for fixed values of x compared to previous results (open squares [ ], open triangles [ ], open circles [ ] and filled squares [ , , ]). the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrature. the data have been corrected to the same reference x as the pre- vious analysis [ ]. the measurements are compared to several nlo and nnlo qcd predictions [ – ]. . . . . . . . . . . . . . . . . . . . . . x - - - x - - - x - - - b b r σ . . . . . . . . . - zeus pb = . gev (best fit) b qcd fit, m = . gev b qcd fit, m = . gev b qcd fit, m zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : reduced beauty cross section, σbb̄r , (filled symbols) as a function of x for seven different values of q . the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrature. also shown are the results of the qcd fit described in section . the central line indicates the best fit, the lower and upper line give the fit for a higher and lower beauty mass, respectively. ) (gev) b (mbm . . . . . . . . . . χ zeus inclusive dis + beauty qcd fit figure : the values of χ for the pdf fit to the combined hera dis data including the beauty measurements, as a function of the running beauty quark mass mb(mb). the ffns abm scheme is used, where the beauty quark mass is defined in the ms scheme. the solid line is a second order polynomial parameterisation of the points. introduction experimental set-up monte carlo simulations theoretical predictions and uncertainties data selection extraction of the heavy-flavour cross sections systematic uncertainties cross sections extraction of f qbarq and rqbarq measurement of the running beauty-quark mass conclusions the "beautiful death" from homer to democratic athens the "beautiful death" from homer to democratic athens nicole loraux, david m. pritchard arethusa, volume , number , winter , pp. - (article) published by johns hopkins university press doi: for additional information about this article [ access provided at apr : gmt from carnegie mellon university ] https://doi.org/ . /are. . https://muse.jhu.edu/article/ https://doi.org/ . /are. . https://muse.jhu.edu/article/ arethusa ( ) – © by johns hopkins university press the “beautiful death” from homer to democratic athens nicole loraux translated by david m. pritchard . introduction from homer’s iliad to the athenian funeral oration and beyond, the “beau- tiful death” was the name that the greeks used to describe a combatant’s death. from the world of achilles to democratic athens, in the fifth and fourth centuries bc, the warrior’s death was a model that concentrated the representations and the values that served as [masculine] norms. this should not be a surprise: the iliad depicts a society at war and, in the translator’s note: this article was published as “mourir devant troie, tomber pour athènes: de la gloire du héros à l’idée de la cité” (loraux ). it was delivered as a paper at the conference, “funerary ideology in the ancient world,” which took place in ischia, italy, in . cambridge university press and the Éditions de maison des sciences de l’homme co-published the conference proceedings. my translation appears here courtesy of these presses. in translating loraux’s footnotes, i include english-language publications in lieu of the french translations that loraux cited or in lieu of french-language works that have been translated into english. the paper’s stated purpose was to summarise the major findings of the three conference papers about the “beautiful death”: those of a. schnapp- gourbeillon , j.-p. vernant . – , and loraux herself, which she published in the invention of athens (loraux . – ). in discussing the major findings of this last book, loraux went well beyond this purpose. i remain indebted to p. cryle and, espe- cially, m. mardon for their valuable help with this translation. therefore i keep the iliad distinct from the odyssey; on the latter, see, e.g., finley . with the achaean camp and the classical city, of course, it is a question of the two absolute endpoints of a long history that the three conference papers did not cover. consequently, in what follows there are gaps, especially on the hero, which is treated by bérard . on the development of the cult of heroes in the cities, which was an essential stage in the process of abstraction, see below. nicole loraux achaean camp at least, a society of men without children and legitimate wives. certainly the athenian polis reversed the traditional combatant-cit- izen relationship by claiming that one must be, first, a citizen before being a soldier. nevertheless, this polis distinguished itself from others by the splendour of the public funeral for its citizens who had died in war and, especially, by repatriating their mortal remains (thuc. . ). in a society that believed in autochthony, this repatriation was, undoubtedly, significant. since the beautiful death crystallised the aretē (“courage”) of achilles and athenians alike, it was, from the outset, linked to speech. indeed, heroic death and the civic beautiful death were the subject matter of elaborate speech-making. such a celebratory discourse gave the warrior’s death an eternal existence in memory. this discourse gave his death its reality, but, conversely, also took for itself all that was valued in his exploit and claimed to be its truthful expression. in short, the beautiful death was a paradigm. . the language of the funeral: the living’s treatment of the dead in order to bury their dead, two communities came together: the army of the achaeans and the athenian city. the former used two markedly different procedures, depending on whether it was burying the ordinary dead or the elite of the heroes. for the non-elite anonymous dead who had not fallen in the front rank, the army of the achaeans acted quickly: they washed the dead bodies, removing blood and dust, and built a funeral pyre. once the cremation was finished, they departed, without, apparently, saying a word (e.g., il. . – ); for it is certain that the achaeans, just like the trojans, abstained from any lamentation before piling the bodies on the pyre (schnapp-gourbeillon . ). to the living’s silence corresponds the silence surrounding the dead, who, as an indistinct cohort, will go and rejoin, in hades, the nōnumnoi (“the nameless”), that is, the masses who are deprived of glory. this relationship went back to the so-called hoplite reform; see, e.g., detienne and vidal-naquet . – . since wailing was essentially feminine, it is significant that women in this particular set- ting were absent. the text also emphasises the ban on lamentation on the trojan side (e.g., il. . ). therefore it is was an important departure, when, among the trojans, the dead heroes were brought home and met with female wailing. in hesiod’s myth of the races, only the elite among the heroes arrive in the isles of the blessed, while the rest reach hades, like the men of bronze, as nōnumnoi dead men (hes. op. – , – ). the “beautiful death” in order to bury the heroes, by contrast, whether it be sarpedon, hector, or, especially, patrocles, a ritual was required to which significant time had to be allocated. this funeral accommodated lamentations, a dis- play of the body ( prothesis), a banquet, and/or games. next it fell to the poet to celebrate the klea andrōn, namely, the glorious deeds of the heroes. in brief, one did not bury thersites, if he were to die, as one would achil- les or as one did bury his “other,” patrocles. there was, clearly, one lot for ordinary men and another lot for the heroes. democratic practice, in contrast to the epic funeral, granted every- one the same honour; for, at athens, the funeral was collective, as were the tomb and the eulogy. but each citizen still had an individual right to his share of glory and to the eternal memory of his name that was inscribed on the funeral monument. a name, it is true, that was both “abstract” and political: without a patronymic and a demotic, the citizen’s name was stripped naked, as it were, and detached from all relationships, such as those in a family or any other group. his name was placed on a list, next to the names of the year’s other dead, who were enumerated within the civic framework of the ten cleisthenic tribes. in this way, democratic egalitari- anism was able to integrate the aristocratic value of glory. some anonym- ity, certainly, governed this funeral, but it was moderate; for if the remains of the dead, which were collected by tribes, were not individualised, each family, at least, had the right to bring offerings to its deceased loved one during the prothesis. an unwritten law encouraged the orator not to praise any individual’s glory in his epitaphios logos (“funeral oration”). but the public monument still implemented a fair division between collective glory, which was given by the verse epitaph, and personal renown, which came from the name’s inscription (loraux . – ). might burying a dead individual or the collective dead be a way for a community to give full expression to the values that provide the soci- ety of the living its structure? if we leave to one side the truly anonymous dead of book of the iliad, this question can be answered by returning to two funerals: those of patrocles and athenian citizen-soldiers. yet before doing so, it is right that we anticipate a criticism. it could be objected that between, on the one hand, the “literary” funeral, whose described ritual is all there is (even if it is realistic: schnapp-gourbeillon . ), and, on the other hand, the funerary practice attested by archaeological evidence, the i am using the term hero strictly in the homeric sense and not in the cultural sense; on the latter, see, e.g., bérard and hartog . nicole loraux distance is much too great. importantly, however, our principal document on the athenian collective funeral is still a text, namely thucydides . —a text that plays an essential role in the overall economy of this historian’s account of the peloponnesian war. consequently, in both cases, the funeral has already become the subject matter of speech, which is something that we will need to take into account. let us go, first, to the funeral of patrocles. it furnishes, at first sight, the classic schema of a hero’s funeral in the iliad. to begin, the dead man’s body is cared for in multiple ways, after which it is displayed in all its beauty and, next, burnt on a funeral pyre. in this cremation, j.-p. vernant sees a process that was the opposite of the one characterising sac- rificial practice (vernant . – ). in the funerary rite, certainly, the corruptible flesh, which was totally consumed, departed in smoke, while the “white bones” survived, which were all that remained of the dead man’s body. in the sacrificial rite, by contrast, the white bones went up as smoke towards the gods, while the flesh remained, destined to be consumed by the community of men. yet patrocles’s funeral only appears to conform to this cremation schema, since this ritual completely mixes up funeral and sacrifice (schnapp-gourbeillon . – ). the sacrifices in it are made aberrant by the status of the victims (men, dogs, and horses). in what is an excessive funeral, patrocles, who is burnt by a double fire, both sacri- ficial and funerary, is the object of a funeral ritual as well as the recipient of sacrificial practice. in a word, he is a divine corpse. what is essential here is that this is what achilles will soon be, because, by honouring patrocles with whom he had a “living connection,” achilles accepts his destiny, a destiny inscribed by death. patrocles’s funeral is, in reality, celebrated by achilles alone, although it takes place in the middle of the achaean army and includes his own people, the myr- midons. this funeral tacitly expresses the complex status of achilles as a hero: his hubris (“insolence”), which constantly leads from all to nothing, and his standing as a living man whose death is written in his (short) life. being neither completely dead nor, for that matter, alive, and a mortal, who is, nevertheless, treated like a god, patrocles reveals achilles’ status as a “living connection” is borrowed from what vernant said in the discussion that followed this conference presentation. as for patrocles as the “double” of achilles, e. cassin evoked the analogous couple in the mesopotamian tradition of gilgamesh and enkidu, and the hubristic funeral that the former held for the latter, whose life is, from then on, no more than a long march towards death. the “beautiful death” living man. until achilles dies one day, patrocles will not truly be one of the dead. his absolutely temporary tomb contains what looks like the white bones and the double layer of fat for a sacrifice that has not yet taken (nor will ever take) place. until he, in his turn, departs for hades, achilles alive is the immortal face of patrocles, just as patrocles was his mortal part. in the end, only death will reunite the two halves of this sumbolon (“token”). patrocles’ funeral therefore brings up to date achilles’ status, his difficult integration into the societies of the living and the dead, and the tension within him that constantly opposes life to death and god to man. in short, achilles and patrocles are the inside and the outside. there is no better way to say that the hero is double. after the heroic funeral, let us turn to the civic funeral’s democratic egalitarianism. again we need to note how this egalitarianism consisted of giving to all what aristocracy reserved for some. aristocratic features of this funeral included the prothesis, which was longer than for the ordi- nary dead, the use of chariots for the cortège (ekphora), the placing of the bones in caskets of cypress, which, as a rot-proof timber, was the bearer of memory and the symbol of immortality, and, especially, the eulogy. this prose oration may have used the language of political debate. but the doxa athanatos (“immortal renown”) of the civic orators looks suspiciously like the kleos aphthiton (“imperishable glory”) of the poet. therefore, the civic funeral certainly did give everyone what the past’s aristocrats had given only to some. to everyone the oration and the verse epigram also gave, officially, the title agathoi andres (“courageous men”). we might ask: did death erase differences? it is better to say that it was the city that erased differences in death, as if democracy’s interchangeable egalitarianism was (only) fulfilled on such an occasion. in death, athenian combatants, who were hoplites, archers, rowers, and peltasts all mixed up, looked like homoioi (“peers”). in light of words such as homoioi and agathoi, was this the equality of democratic athens or an aristocracy? what the public funeral spoke of was democracy as it wanted to be, that is, as it wanted to be thought of. consequently, we can say that the athenian funeral did indeed give expression to the “reality” of the society of the living—as long as we designate as real what this society wanted people to say about it or what it said about itself. this society kept saying the same thing, despite all the transfor- mations that it underwent. in the fourth century, the funeral oration with its strict orthodoxy resisted the intrusion of private values that were again growing in the city (loraux . – ). but the historian cannot forget nicole loraux that even on the edges of the dēmosion sēma (“public cemetery”), private tombstones began again to proliferate. some of them even went so far as to celebrate individually citizens who had been interred in a collective monu- ment. in this way, family devotion duplicated official values, just as, in the ceramicus, the “street of tombs” duplicated the dēmosion sēma. the most remarkable case is that of dexileos, who was, probably, interred in the col- lective monument of . he was definitely twice celebrated individually: first, with the hippeis (“horsemen”) who had distinguished themselves at the same time as him and, second, by the monument that his family erected for him. this tomb’s epitaph formed a biography, while its relief cut him off from the other combatants (loraux . ). in the face of all this, however, the civic funeral and the funeral oration never tired of saying that the collective had primacy over the individual and the public over the private. it is time that we really examine this speech. . heroic and citizen deaths: from the beautiful dead to the beautiful death in homer’s world as much as in the athenian city, an important place was made for speech on the beautiful death, because ceremonial practices in both honoured the dead by speaking to the living. while speaking of the “language” of rites, we are not overlooking that the combatant’s death is literally surrounded on all sides by speech. this speech, whether it be the poet’s or the orator’s, formed the beautiful death by celebrating it. yet inside this speech, there was another speech that the combatants were supposed to have rehearsed for themselves before risking their lives. we find this internal deliberative speech in, for example, sarpedon’s address to glau- cus, this “other” who is just like him, in book of the iliad (vernant . – ), and in the monologue of the athenian combatant in lysias’s these monuments’ inscriptions are, respectively, rhodes and osborne .nos. a and b. the casualty list of (ig ii ) is too lacunose to affirm with certainty that it included dexileos’s name. during the discussion that followed, c. bérard objected that this young athenian had probably been buried not in, not the collective monument, but the one for the hippeis, among whom he was counted. yet i would be inclined to see the latter as a simple honorific monument, probably a cenotaph, which duplicated the collective monu- ment where all the year’s dead were buried. as for the private mnēma (“funeral monu- ment”), i agree with him in seeing there something like a claim on the part of the family for the “personal part” of the combatant. the “beautiful death” epitaphios logos (loraux . – ). this internal speech is like the poem’s matrix and the funeral oration’s truth. the bard and the orator take it upon themselves to be its faithful interpreters. certainly this internal speech had a “deliberative” form, because it came before a choice, even if it was only possible to choose immortal glory and so the beautiful death. the reasons for this choice, in homer, were “metaphysical,” because men can escape neither death nor old age, which was like a living death, and because it was better to immortalise the hero’s beautiful youth (vernant . – ). the reasons in the funeral oration were “political,” because the city wanted it so, but we could say that this politics was another form of metaphysics. because the warrior’s death, as a supreme exploit, irresistibly called for the poet’s song or the orator’s prose, it turns out that the beautiful death was already in itself speech. it was a rhetorical topos (“commonplace”) that was the privileged place for the implanting of an ideology. from the heroic death to the civic death there was, like a long chain’s outermost links, a real continuity, even if gaps and ruptures or, most accurately, a series of gaps and rup- tures had their place. speech about the beautiful death was built on a certain number of common claims. in one go, this death realised the aretē of a combatant. it established the youthfulness of homeric warriors, who were immortalised in the flower of their life, and sanctioned the athenian soldier’s access to the status of an anēr (“man,” that is, a virile adult), who was inextricably both a citizen and a soldier. there are two ways to understand “they died, after having shown themselves to be courageous men” (andres genomenoi agathoi), which was the funeral speech’s key phrase depending on whether we put the emphasis on agathoi or privilege andres. in the first reading, which is the most common, it appears that an athenian only became coura- geous in death. if more weight is given to andres, the more unusual read- ing, the funeral oration appears to be saying that an athenian becomes a man, that is to say, a citizen, only in death. the glorious death also widened a gulf between the hero, or the agathoi, and the rest of humanity. in the iliad, where people only died in war, a line divided the anonymous death of ordinary people from the the funeral oration appears to make no distinction between andra gignesthai (“to become a man”), which designated political majority (registration in the deme register), and the dead man’s registration on the official casualty list (andra genesthai agathon, “having become a courageous man”). nicole loraux beautiful death of sarpedon or patrocles. in the funeral oration, the spec- tacular death of the anēr agathos (“courageous man”) separated him forever from passive humanity, who, trapped on earth, waited to suffer their fate (loraux . ). yet in both cases, the elite’s chosen death is opposed to ordinary men’s unchosen one. therefore the glorious death unfurled in the domain of the absolute: all the world’s treasure could not counterbal- ance the demands of honour that drove achilles, while no prestige [off the battlefield] would be sufficient to launch sarpedon into battle’s melee. the military exploits of the athenians likewise responded not to any utilitar- ian consideration but only to the quest for aretē. all occurred as if the heroic beautiful death continued to inform the civic version of the combatant’s death—as if, as it were, the city’s dis- courses were feeding off epic representations. yet this does not mean that there was no rupture between the civic beautiful death and the heroic one. indeed, we can detect multiple gaps from one to the other. we can observe them more easily by taking as our reference point the civic beautiful death, which looks like the end of a long history. while epic gave itself as sub- ject matter the klea andrōn, that is, glory that had already been realised in actions, the athenian speech resolutely erased the action behind the decision to die (loraux . – ). in the funeral oration, everything comes down to this choice, which leads to death. between the decision to die and the report of the beautiful death (andres genomenoi agathoi), there is no room for action or for an account of exploits. consequently, life is erased behind death for the reason that all that counts is the instant of the decision that is both the beginning and the end of the (true) life. another reason for this erasure is that the eulogy’s collective character requires that all the dead share the same praise, without consideration being given to the quality of their past lives. for epic’s heroes, such as achilles in book of the iliad, there was, by contrast, no other value than life. it was precisely for this reason that it was worth putting one’s own life at stake: one found death but became exemplary, while the beautiful death took on all the weight of the lost life. it was left to the poet to sing of the hero’s life that had been perfected forever by his death. the hero went to his death because life was every- thing for him. the funeral oration, by contrast, encouraged the citizen to risk a life that was nothing in order to serve the city that was everything: for there was no other life than the city’s, which was also his [personal] history. to the citizens there remained only death. whereas epic, which, once again, was more “realistic,” mentioned casualties who got better, the the “beautiful death” athenian speech celebrated the citizens only in death. in brief, everything in the athenian funeral conspired to erase life. this is the meaning of the transfer that made eternal youthfulness, characterising the person of the dead warrior in epic, a feature of the glory or praise of citizens. to the athenian dead, the funeral oration promised agērōs epainos, that is, praise that did not grow old. but who, if not the city, possessed this praise? we might wonder whether, according to the funeral speech’s criteria, a citizen was even a person. a person is a sōma (“body”) and a psukhē (“soul”). in epic, sōma is the term for the dead person, while what gives formal unity to his body, after his death, is his face. it is this face that an enemy tries hard to destroy and that a dead man’s relatives immortalise in the funeral ritual. the body, which has been embellished and consumed, is broken down, but the psukhē, which is liberated in this way, reaches hades’ shores (vernant . – ). finally, seated atop the white bones, which are the absent body’s sole remains, the mnēma (“funeral monument”) speaks to the living about the dead man. in the kingdom of the shades, there is the psukhē, and in the world of humans, the memory of the dead man, which is immortalised by the mnēma and the poet’s song. in epic, all is played out between these three terms: sōma, psukhē, and mnēma. the funeral oration, which is based on cut-and-dry oppositions, knows only two terms: there is, on the one hand, mnēmē (“memory”), which is always immortal, and, on the other, “life,” of which citizens can only have usufruct. this life is always undervalued and described indis- criminately as sōma, psukhē, or bios, almost to the point of unfamiliarity. from this there is an enormous consequence: the dead, it appears, have no more body than they do life. here the essential point is evident: the change from the beautiful dead man to the beautiful death. in epic, the body was a spectacle. by immobilising it, the heroic death dramatised the body’s beauty. this beauty of the young fallen war- rior was his glory’s visible sign. the ritual aimed to emphasise it by focus- sing on it. such is the meaning of the prothesis, in which a corpse that has been meticulously embellished is displayed, because, at this point in the funeral, the dead man’s person is entirely linked to his sōma (ver- nant . – ). the athenian funeral, by contrast, was built around the here i am drawing on vernant’s course at the collège de france ( – ) on the funeral code in ancient greece. nicole loraux systematic occultation of the body. in the speech, first of all, there appeared no beautiful dead man but only always the beautiful death. in it all aes- thetic value had disappeared and the “beautiful” was moral. therefore a double transfer had taken place: from the dead man to death, that is, from an exemplary individual towards a formal model of civic behaviour, and then from the beautiful as the body’s quality to the beautiful as the action’s quality (loraux . – ). as the action, moreover, was absorbed into logos (“speech”), in the end, the beautiful was used to describe the quality of the civic speech. for priam, “all that appears ( phanēēi) on the young dead warrior is beautiful” (il. . ). the civic speech responded to epic’s “appears” with the always repeated epiphany of athens’ aretē. yet it was not just the funeral ceremony that failed to make room for showing the dead’s bodies. in the iliad, the assembly of the gods decided to force achilles to return hector’s corpse ( . – ), because it had to be delivered before the eyes of, first, his spouse, then, his mother, son, and father, and, finally, his people. in athens, by contrast, the dead no longer looked like a sōma, and what the city agreed to display for family devotion were bones. in this way, the dead were already abstract and already deprived of all that gave them their physical appearance and all that permitted them to be identified. in actual fact, the order of the funeral ritual had been reversed for athens’ citizens: first, the funeral pyre, on the battlefield, and, then, for the families, a prothesis without spectacle or individualisation. in view of this, we cannot underestimate the significance of the cremation of the bodies. was burning the dead instead of burying them only a prophylactic measure? was it simply about conserving their remains until the funeral ceremony at the combat season’s end? certainly there are a in classical athens, the notion of the “beautiful dead man” no longer had a reality. there- fore in euripides’ suppliant women, the dead’s mothers must be spared the sight of “dis- figured bodies, which are a hideous spectacle, the blood and the wounds of the corpses” ( – ). thuc. . . : ta osta protithentai (“they display the bones”). in homer’s iliad, the impossibility of identifying the dead characterised the mass of the ordinary dead (e.g., . ). euripides’ suppliant women, which is a tragic reflection on the public funeral, presents the stages in the same order: first, the funeral pyre in the presence of the political and military leaders and then the display of the bones, which the mothers can attend ( – , – ). it is significant that there was in attendance at this cremation the army, which was the inheritor of the laoi (“peoples”) that were, in epic poetry, the last invitees to the funeral spectacle. the “beautiful death” great number of historians who are convinced that the real is rational and so answer in the affirmative. but to him or her who acknowledges that ancient greece is also a matter of anthropology, such rationality appears really suspect. to tell the truth, the recourse to cremation strongly resembles a choice that was dictated by ideological imperatives. we can note that this prophylactic measure would have had no raison d’être if the athenians did not repatriate the remains of their citizens. in doing so, they distinguished themselves from other greek cities who normally buried their dead on the battlefield. now the meaning of this athenian practice is clearer still when it is related to the dominant myth of autochthony. for the athenians, their civic earth was both “a mother and a fatherland.” was entrusting their war dead’s bones to it therefore not a way to guarantee the city’s reproduction? this choice of repatriation, at least, made it necessary for the athenians to concern themselves with prophylactic measures. yet there was more to cremation than this. as a funerary practice, it was a matter of symbolism and could, itself, be subject to choice. after the battle of marathon, combatants were buried on the battlefield. what was absolutely symbolic, in this case, was the dividing up of, on the one hand, the citizens, for whom the athenians resorted to cremation, and, on the other, the plataeans and the slaves, who were simply buried some distance away. in interpreting this division, we can take into account that cremation, as a more costly practice, was reserved for those whom the city wanted to honour highly (kurtz and boardman . ). undoubtedly, we need also to take into account that the athenian citizens, who, by their deaths, had put beyond doubt their status as andres, were, as was natural, on the side of the cooked, while the plataeans and the slaves, like the children in eretria’s princely tombs (bérard ), were on the side of the raw. ear- lier we noted how the funeral oration habitually presented those who had fallen in battle as having, at last, definitively left behind their childhood. when it comes to funerary practice, were there, it can be asked, behaviours that escaped symbolism? because i do not believe that there were, i have had to dwell at some length on the athenian refusal to make to those who, in the discussion that followed, insisted on the importance of “health rea- sons,” the talk by d. lombard on the ancient south-east asian funeral ( ) provided a definitive answer: in this funeral practice, which consisted of keeping a corpse rolled up in cloth inside the house for years (sometimes up to three), where is there a prophylactic measure? plato said this explicitly in his menexenus ( c). nicole loraux room for display in their funeral ceremony. from the beautiful dead man to the beautiful death, a major change had occurred: the effacing of the person of the dead man or, more precisely, the dead themselves before [the ideal of] the city. to put it differently, this was the creation of the city ideal beyond all the representations of the polis as a community. in short, this creating of an ideal was a process of abstraction. . the dead and the abstraction of the city: achilles and athens such a process is not carried out in a day. indeed, clearly, this process was not carried out in all places nor at the same speed. different speeds, delays, and gaps are, of course, peculiar to ideological phenomena. while limit- ing this examination to the two extremes of the beautiful death’s history, we must not forget that between the homeric world and athenian democ- racy essential stages had intervened, such as the archaic period’s aristo- cratic cities or sparta. in the classical period, the greeks saw sparta as embodying very rigorously the civic obligation of the beautiful death. it is worth studying this, if only briefly, in order to take note of the remarkable discrepancy there between discourse and practice. this city, from its sixth- century beginning, was protected from the temptation of development by its immoveable social structures and, in the next century, looked like an archaic polis that had been miraculously preserved. sparta demonstrates that the process of abstraction was not an irresistible phenomenon across the greek world. in many respects, sparta’s choices are even reminiscent of those of epic. in sparta, room was made for the life of the courageous warrior. let us recall the quasi-institutional opposition, in the city of the homoioi, between he who had fought glori- ously and so merited, in his lifetime, honours, admiration, and sexual attention, and the tresas (“trembler”), who was pushed out of the city and even its age classes, since he was required to give up his seat to a younger (and more courageous) spartan (e.g., tyrtaeus . – , . – prato). along the same lines, probably, the spartans, like the homeric on the aristocratic funerary practices in archaic cities, see, e.g., bérard . on the unequal development of different greek cities in the classical period, see, e.g., austin and vidal-naquet . , . on spartan social structures, see, e.g., finley . on the tresantes (“tremblers”) and the spartan representations of the beautiful death, see, e.g., loraux . – . the “beautiful death” laoi (“peoples”), judged it essential to possess not just the remains but also the bodies of their kings. if a king died away from sparta, his body, which was embalmed in honey or wax, had to be brought back, with special care taken to preserve his face. sparta’s male–female opposition included women in the city more than in athens. attic women had to be content with the (small) place that was allotted them in the civic funeral. beyond this ceremony, as pericles politely reminded them (thuc. . . ), they were counselled not to be spo- ken of. for pericles, feminine aretē was simply a contradiction in terms. spartan women, who enjoyed the right to attend a royal funeral, could also win renown in the sphere of reproduction, even if this sphere, it is true, was tightly confined. only spartan men who had fallen in battle and spartan women who had died in childbirth had the right to the inscription of their names on their tombs. while this equivalence might conform to the greek orthodoxy about the division between the sexes, it is no less remarkable for being institutionalised. from the spartan viewpoint, we can see more clearly the abstraction process that was implemented in athens. yet this does not mean that other essential stages did not exist along the way to this athenian beautiful death. this process of abstraction, besides not being implemented in every place, was implemented or, at least, was orchestrated on an exceptional scale in a very exact place: athens. this, too, happened at a very exact time. the funeral oration’s moment, let us say, fell between cleisthenes and ephialtes. more generally, it fell between cleisthenes and the start of the peloponnesian war. this period witnessed the disappearance of the dead’s figurative representation on athenian private tombs, although such representation did continue on public monuments. in funerary representa- tions there existed, therefore, a gap separating archaic sculpture, such as the in the discussion that followed, d. lanza drew my attention to the strange epitaphios logos that electra delivered over aegisthus’s body (eur. el. – ). this is a “bad” funeral oration because it is a question of blame, not praise; the kratos of the situation is empha- sised; and, most importantly, it is a woman who delivers it. only tragedy could subvert the tradition of the funeral oration by giving speech to, of all people, a woman. on the equivalence of marriage and war as the respective natural accomplishments of men and women, see, e.g., vernant . – . e.g., the triumphing of speech in the world of the cities, and the claim, constantly repeated in pindar, of the total supremacy of celebratory speech over action. while i am inclined to date the funeral oration’s introduction to around , i believe, along with jacoby , that it stood at the end of a long maturation process that was carried out between cleisthenes and ephialtes (loraux . – ). nicole loraux kouros stela, from the late classical period’s innumerable figurative reliefs. certainly this phenomenon merits an in-depth study. to understand this gap, we, undoubtedly, would need to explore the civic ban that weighed against the individual’s representation in death and—in a more general way—against sight to the benefit of speech. subsequently, we would need to bring together this ban and the study of the public funeral. clearly the athenian city never stopped exorcising sight: it sub- stituted white bones for bodies. it diverted the eye from the collective monument, on which a relief sculpture celebrated symbolic combatants, towards the rostrum of the dēmosion sēma, where the official orator’s speech transformed the public into an audience. therefore, the speech that the classical city heard about the beautiful death was formed by a rejection of archaic representation or, indeed, of all representation. here, perhaps, we see less the rejection of archaic discourse than of representation. let us return to this speech one last time. everything occurs in the funeral oration as if athens were taking the place that achilles occu- pies in epic. achilles, the most valorous of the greeks, parallels athens, the city of aretē, to which the greeks, by mutual agreement, supposedly award the aristeion (“the first prize for valour”). no one in the achaean camp contests achilles’ eminent merit. no greek city, if we are to believe the orators, denies for a second that athens merits universal admiration and placement in the first rank. like achilles, the city can only be the greatest. this is why the victory at marathon, which was an initiatory exploit of the hero-athens, gained paradigmatic value. while plataeans actually fought besides the athenians, the orators “forget” them, because athens gives no thought to allies (loraux . – ). finally, just as achilles-bard sings of the klea andrōn, so, too, within civic discourse, the city gives speech to the orator and glory to its dead citizens. this heroic position of the city in the funeral speech was not with- out consequences. it basically gave the combatants an interchangeable face, a. c. w. clairmont objected that on a public monument, the relief sculpture praised gen- erally the physical beauty of the combatants. my response to this objection is that it was a question of a “beauty” that was thoroughly symbolic and that the eye is not the only thing that can perceive; see, e.g., loraux . this transfer from sight to hearing can clearly be seen in the preamble of lysias’s epi taphios logos. in rejecting all representation, the funeral oration can be characterised as deploying an imaginary with an image. for what follows about achilles, see, especially, vernant . – , – . the “beautiful death” which, in reality, meant that they did not have a face at all. therefore, the funeral oration proclaimed the dominance of the polis over andres, of the city over men. to speak plainly, this should discourage the historian of the greek city from overemphasising the importance of the well-known adage: “men are the city.” against the idea that greece of the poleis knew only the community’s concrete lived experience, the study of the funeral ora- tion’s beautiful death urges us to emphasise the dominant position that the abstraction of the polis held in civic discourse (loraux . – ). this abstract polis was the indivisible unity around which speech was organised. in order to complete the comparison of achilles in epic and the city in the epitaphios logos, we should also note that the city, if it takes achilles’ place, does so in a moralising fashion. the funeral oration is a (civic and hoplitic) lesson in morality, which epic poetry, clearly, was not. therefore this speech represents the end of the hubris that formed the homeric hero in all his ambiguity (e.g., schnapp-gourbeillon . , – ; vernant . – ). in the epitaphios logos, excess lies elsewhere, among enemies, while all justice has taken refuge in athens. with this major difference is associated the very strong opposition between, as i called it earlier, epic’s realism and the athenian speech’s metaphysical absolutism. we can also associate it with the funeral oration’s systematic occultation of the kratos (“power”) that was a big part of epic’s definition of the warrior. when it came to the kratos that the people exercised within the city, the epitaphioi logoi suggested that democracy was not the kratos of the people, but the fatherland of aretē (loraux . – ). funeral speeches, likewise, suppressed the imperial city’s kratos, transforming it into a recognition of the merit of athens in a contest for excellence (loraux . – ). power per se simply did not have a place in the funeral oration. therefore, what was said in the public cemetery on the occasion of the death of athenians merits the label “ideology of the city.” to this, perhaps, we should add “ideology of democracy,” since manifest egali- tarianism existed only in death and by a claimed adherence to aretē. yet it is very significant that the funeral oration contained the only methodi- cal discourse that the athenian city officially maintained on democracy. democracy spoke for itself in the public cemetery. it described itself as the one true value, and even as the model of the polis. yet in order for this in the sense that it is the “city” that gave this speech such coherence and enabled it to resist the discordant material that the “real” could have introduced. for a different approach, see lanza and vegetti . nicole loraux description to succeed, the democratic city still had to depart from politi- cal practice, for in the ekklēsia, the citizens had fewer scruples about call- ing kratos by its name, and also from the town, because the ceramicus, as the “most beautiful suburb” (thuc. . . ), was still beyond the walls. the city also deliberately departed from time, as pericles all but stated in thucydides (“we will be admired by men today and in the future,” . . ). the pause that death brought allowed such a breaking away. . conclusion: ideology and “funerary ideology” but was this funerary ideology? rather i would say: ideology in death. unless we are prepared to read the ideology in funerary ideology vaguely as a “system of representations,” we really must try to understand the process that allowed an ideological discourse’s dissemination in a death celebration. a ritualised death had become an effective factor in social cohesion. thus it is important that civic ideology was formed against the beautiful death’s background. the hero, achilles, set up a unique ceremonial for honouring patrocles in a manner that had never (and would never) be seen. but this hero was unique among the heroes. at least he should be or even had to be in order to fit in—in his paradoxical manner—in homeric society. against time and against its own history, which had not consisted of [heroic] agonistic wars nor of unsullied prestige, the athenian city set up a ceremonial that distinguished it from other cities and in which it pro- claimed that it was the only polis. this is a discourse that historians have had (and continue to have) difficulty in leaving behind. we are accustomed to pay little attention to the phraseology of our modern speeches for the dead. it is, therefore, pleasing to me that the most effective of the athenian models of athens was articulated in a cemetery. bibliography austin, m. m., and p. vidal-naquet. . economic and social history of ancient greece: an introduction (rev. and trans. m. m. aus- tin). berkeley. bérard, c. . eretria iii: l’hérôon à la porte de l’ouest. berne. . . “récupérer la mort du prince: héroïsation et la formation de la cité,” in gnoli and vernant . – . detienne, m. . “la phalange: problèmes et controverses,” in j.-p. ver- nant, ed., problèmes de la guerre en grèce ancienne. paris. – . the “beautiful death” finley, m. i. . “sparta,” in j.-p. vernant, ed., problèmes de la guerre en grèce ancienne. paris. – . . . the world of odysseus. harmondsworth. gnoli, g., and j.-p. vernant (eds.) . la mort, les morts dans les socié tés anciennes. cambridge. hartog, f. . “la mort de l’autre: les funérailles des rois scythes,” in gnoli and vernant . – . jacoby, f. . “patrios nomos: state burial in athens and the public cemetery in the kerameikos,” jhs . – . kurtz, d., and j. boardman. . greek burial customs. london. lanza, d., and m. vegetti. . “l’ideologia della città,” in d. lanza, m. vegetti, g. calani, and f. sircana, eds., l’ideologia della città. naples. – . lombard, d. . “la mort en insulinde,” in gnoli and vernant . – . loraux, n. . “hēbē et andreia: deux versions de la mort du combat- tant athénien,” ancsoc . – . . . “mourir devant troie, tomber pour athènes: de la gloire du héros à l’idée de la cité,” in gnoli and vernant . – . . . the invention of athens: the funeral oration in the clas sical city (trans. a. sheridan). cambridge, mass. . . the experiences of tiresias: the feminine and the greek man (trans. p. wissing). princeton. rhodes, p. j., and r. osborne (eds.) . greek historical inscriptions – bc. oxford. schnapp-gourbeillon, a. . “les funérailles de patrocle,” in gnoli and vernant . – . vidal-naquet, p. . the black hunter (trans. a. szegedy-maszak). baltimore. vernant, j.-p. . myth and society in ancient greece (trans. j. lloyd). new york. . . mortals and immortals: collected essays (ed. f. i. zeitlin). princeton. wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top 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clare elizabeth caldwell suspend belief for the next two minutes and imagine that you own a ferrari testarossada gleaming red marvel; the marriage of art and engineering. you and this breathtaking morsel of mechanistic beauty have been together for so long that you can’t remember a time when you were not as one. you know each other intimately. or do you? one sunday afternoon as you snake along the chicanes of a high mountainous road, the testarossa emits a sickening bang. you pull the wheezing ball of exhaust fumes to the side of the road and pop the bonnet. when you lift the shining scarlet cranium and peer into the smoking beast, there is not a scintilla of recogni- tion. you realise that you’re looking at an entirely foreign being. now imagine that being is you. for more than years, human beings have been peering under the bonnet of that metaphorical testarossa. the ancient greeks had a very good crack at unravelling the mysteries of the human mind and body well before the modern era. the grecian physician herophilus can take much of the credit, distinguishing the difference between motor and sensory nerves in around bc. but it is only within the last years or so that significant leaps have been made in understanding the functions of the human body and the nuances and implications of those functions. in this issue, geoffrey schott examines how french neurologist guillaume duchenne looked under that bonnet and made scientific and aesthetic discoveries that changed the world of neuroscience forever and continue to do so some years later. as schott discovered, duchenne’s mécanisme received a cool reception when it was first published in . however, the monograph went on to become a bible of facial anatomy, and in particular facial expression. in it, duchenne claimed that each mental function correlated with a single particular muscle and its move- ment. immersed in the minutiae of this study, the frenchman focused his atten- tions on the corrugator superciliida small eyebrow muscle (figure ). having introduced localised faradisation as a method of studying facial muscles in the s, duchenne employed his new techniques to illustrate how ancient greek artists had used the humble corrugator supercilii to convey the emotion of pain. it seemed that the pre-christian sculptors had made a valiant effort to capture the power of this tricky little muscle, but had not quite nailed it in their depiction of the trojan priest, laocoön, in about bc. and it was not duchenne alone who opined that the greeks might have got it wrong. on revisiting the th century mécanisme, schott confirms that other notable luminaries, including naturalist charles darwin and eminent surgeon sir charles bell, concurred. duchenne concluded that, just as the hellenistic sculptors before them had done, the greco-romans had erred in the name of beauty. and who could blame them? so, as we return to our testarossa, smouldering by the side of the road, we are again reminded of how often humans err in the pursuit of the sublime. perhaps duchenne would have gazed under the bonnet at the labyrinthine network of pumps and pistons and declared that the car’s design was its achilles’ heel; that its elegance had impeded its performance. however, i suspect schott may have assessed the same enigma and drawn a very different conclusiondthat the inner workings had allowed for the supreme beauty of the outer shell, however flawed it may have been. competing interests none. provenance and peer review commissioned; internally peer reviewed. received june accepted june references . schott gd. duchenne superciliously ‘corrects’ the laocoön: sculptural considerations in the mécanisme de la physionomie humaine. j neurol neurosurg psychiatry . duchenne gb. mécanisme de la physionomie humaine, ou analyse électro-physiologique de ses différents modes de l’expression. paris: archives générales de médecine, p asselin. . figure faradisation du muscle frontal e dr guillaume benjamin amand duchenne demonstrates his new neurophysiological methods in the s. correspondence to clare elizabeth caldwell, web editor, jnnp, bmj publishing group ltd, bma house, tavistock square, london wc h jr, uk; clarecaldwell@yahoo.com editorial commentary ▸ http://dx.doi.org/ . /jnnp- - doi: . /jnnp- - j neurol neurosurg psychiatry ; : . open access this is an open access article distributed in accordance with the creative commons attribution non commercial (cc by-nc . ) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. see: http://creativecommons.org/licenses/by-nc/ . / published online first july j neurol neurosurg psychiatry january vol no ; : – . o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://jn n p .b m j.co m / j n e u ro l n e u ro su rg p sych ia try: first p u b lish e d a s . /jn n p - - o n ju ly . d o w n lo a d e d fro m http://jnnp.bmj.com/ introduction 국제화와 글로벌 지식경제 사회로의 진입에 발맞춰 국내 노동시 장과 청년실업의 한계를 극복하고자 고등교육 기관의 글로벌 인재 양성을 위한 노력이 한층 강화되었으며, 국제적 역량 계발을 위한 교육 및 훈련 프로그램의 운영이 전 세계적인 현상이 되고 있다(kim & kim, ). 정부는 청년 실업문제를 해소하고 세계적인 안목을 가진 글로벌 인재를 양성하기 위한 전략으로 대학 졸업자들의 해외 취업을 적극 추진하고 있으며, 대학은 학생들에게 외국기업 등에서 다양한 문화를 경험할 수 있는 기회를 제공하고, 전공관련 업무지식 과 기술을 향상시켜 궁극적으로는 국·내외 취업을 촉진시킨다는 목 적으로 해외인턴쉽과 해외취업을 확대하고 있다(lee, ). 해외취업은 한 국가의 노동력이 자기나라의 영토를 벗어나 외국 에서 경제적 수입을 목적으로 일정기간 고용되어 일하기 위해 자발 적인 의사에 따라 일시적으로 이동하는 현상을 의미하지만(yoo et al., ), 국가 및 개인의 사정에 따라 현지에 정착하게 되는 경우 도 있어 해외취업이 해외이민으로 전환되는 계기가 된다. 세계 경 제의 침체로 인한 실업문제는 앞으로 단기간에 개선되기 어려울 전 망이며 국내 시장만을 대상으로 해결책을 찾는 데에는 한계가 있어 청년층의 해외취업진출을 통한 고용확대를 적극적으로 모색할 필 r e s e a r c h a r t i c l e open access copyright ⓒ korea institute of dermatological sciences. this is an open access article distributed under the terms of the creative commons attribution non-commercial license (http://creativecommons.org/licenses/by-nc/ . ), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. work experience and satisfaction among beauty graduates in foreign countries eun young jung , mee young park * department of beauty art, cheju halla university, jeju-si, jeju-do, korea department of nursing, cheju halla university, jeju-si, jeju-do, korea *corresponding author: mee young park, department of nursing, cheju halla university, halladaehak-ro, jeju-si, jeju-do , korea tel.: + fax: + email: misty @chu.ac.kr received october , revised february , accepted february , published march , abstract purpose: this study was conducted to investigate the status of beauty graduates working in foreign countries and identify the factors affecting the satisfaction/ dissatisfaction with regards to their work experiences in foreign countries. methods: target population of the study was beauty graduates from four korean universities who are currently employed or have worked in foreign countries at least once. the response rate was %, and completed survey questionnaires were included in the final analysis. results: the majority of respondents were women ( . %) aged less than years ( . %). of these, . % were skincare specialists and . % were hair specialists, most of whom ( . %) worked in australia and new zealand. the main motivation was to experience foreign cultures ( . %) and . % went out through their university support programs. of the respondents, . % worked at shops owned by koreans and . % worked from six months to one year and . % worked over one year by the time of the survey. furthermore, . % of the respondents received pre-job training for six months or less and . % received it for less than three months. respondents agreed that their training period was appropriate. the majority ( . %) of respondents participated in some sort of language training and . % said that their language training was most helpful. foreign cultural experience and improvement in language skills were the factors that affected their satisfaction the most with regards to their work experiences in foreign countries. in contrast, dissatisfaction factors comprised the lack of welfare, including accommodation issues and low salary. conclusion: the findings of this study are expected to be used as a basis to develop student training programs for those who wish to work in foreign countries. keywords: beauty graduates, foreign work experience, pre-job training, satisfaction, language training issn - (print) issn - (online) asian j beauty cosmetol ; ( ): - http://dx.doi.org/ . /ajbc. . work experience and satisfaction among beauty graduates http://dx.doi.org/ . /ajbc. . 요가 있다. 청년층의 해외취업진출은 중장기적으로 국가 경제발전 에 긍정적인 영향을 미치며, 해외와의 활발한 인적 교류를 통한 새 로운 기술의 획득, 해외 직장 경험 등으로 글로벌 인재 양성, 국제 적 네트워크 형성 등의 경제외적인 효과도 극대화할 수 있는 등 다 양한 이점이 있다. 그럼에도 불구하고 현재 청년 해외취업 프로그 램의 운영이 체계적이지 못하여 실질적인 성과는 기대만큼 높지 않 은 실정이다(kwon & kim, ). 현대인들은 경제 수준의 향상과 더불어 문화적인 의식 수준도 크게 향상되어 내적인 미(美)와 외적인 미를 동시에 추구하고 있다. 최근에는 외적인 아름다움에 대해 더 큰 관심을 보이고 있어 이러 한 시대적 요구에 따라 미에 대한 가치 기준이 변화·발전되고 있 으며, 미를 창조하는 미용인의 업무 또한 전문화되고 세분화되어 가고 있다(kang & rhee, ). 현대 사회는 뷰티를 좀 더 확장적 이고 주관적인 개념으로 받아들이고 있으며, 이러한 맥락에서 뷰티 산업도 화장품 산업에만 국한되는 것이 아니라 ‘인체를 아름답고 건강하게 관리하기 위해 서비스를 제공하는 산업’으로 정의되며 두 발미용, 피부미용, 메이크업, 네일아트 등의 미용 관련 산업을 포함 하고 있다(chin, ). 미용업은 단순한 기술직이 아니라 전문지식과 섬세하고 숙련된 기술을 요하는 전문직종이며 고객과의 접촉을 통한 작업시간이 다 른 서비스업에 비해 장시간에 걸쳐 이루어지므로 인적자원의 역할 이나 비중이 상대적으로 크다(jeon, ; jung & park, ). 그 러나 일부 대기업을 제외하고는 국내 뷰티 산업계의 근무환경이 열 악한 상태이며, 전공관련 업무지식과 기술을 향상시킬 수 있는 기회 가 적어 대학의 지원을 통한 인턴쉽이나 해외취업을 확대할 필요성 이 크게 대두되고 있으며, 해외인력진출을 통해 일자리 창출 및 인 적 교류를 적극적으로 추진해야 한다는 주장이 설득력을 얻고 있다. 해외취업에 관한 선행연구는 치위생사와 치기공사의 해외취업 에 대한 선호도에 관한 연구(kim & kim, ; yoo et al., ), 해외취업 및 인턴쉽에 대한 인식 및 만족도에 관한 연구(choi et al., ), 해외취업의 활성화 방안에 관한 연구(cho et al., ; kim, ; kwon et al., ; kwon & kim, ) 등이 있다. 이외 해외인턴쉽의 성공요인에 대한 분석(lee, ), 병원간호사 의 해외취업 의향에 영향을 미치는 요인(lee & son, ) 등이 보고되었다. 뷰티 분야의 해외취업 관련 연구로는 일본 고용시장 의 효율적인 접근방안(jun, )과 뷰티학과 학생들의 해외인턴 쉽 및 해외취업에 대한 인식과 취업준비 행동(park, ) 등에 관 한 연구만이 진행된 상황이다. 위와 같이, 해외취업에 관한 선행연 구는 일부 취업군에 국한되어 있거나 해외취업군에 대한 취업 현황 이나 취업 후 전망에 대한 분석보다는 편의적 표본을 대상으로 하 는 해외취업에 대한 선호도 조사에 그치는 경향이 있고, 뷰티 분야 실제 해외취업자를 대상으로 한 연구는 전무한 실정이다. 따라서 본 연구의 목적은 뷰티를 전공한 해외취업자의 현황을 파악하고 만족도에 영향을 미치는 요인들을 조사하여 참가자들의 현실적 요구 등에 기반한 지원방안을 도출하기 위한 기초 자료를 마련하기 위함이다. methods . 연구대상 및 자료수집방법 본 연구는 국내 개 대학의 뷰티 전공 해외취업 참가자를 대상으 로 년 월 부터 월 까지 개월간 실시하였으며, 설문 응답자 는 현재 해외취업 중이거나 회 이상 해외취업을 다녀온 경험이 있 는 대학 졸업자였다. 응답자가 연구설명문에 제시된 연구의 목적과 설문 내용을 읽고 설문에 응답하면 연구 참여에 동의한 것으로 간 table . demographics of respondents (n= ) categories items n % gender male . female . age and under . and over . major subject hair . skincare . makeup . nail-art . others . education bachelor . associate bachelor . others . marriage status never married . married . countries worked in australia, new zealand . asia including china and japan . 뷰티 전공자의 해외취업 실태 및 만족도에 미치는 요인 http://www.e-ajbc.org 주됨을 미리 알려주었다. 총 배포된 부 중 부가 회수되어 응답 률은 %를 기록하였고, 그 중 불성실 응답 설문지 부를 제외한 부가 최종 분석에 사용되었다. . 연구도구 연구도구인 자가응답형 설문지는 연구자가 문헌 고찰과 관련 분야 전문가와의 상담을 통해 최근 동향을 파악한 후 초안을 설계 하였고, 통계 전문가의 자문을 거쳐 최종 완성하였다. 설문지의 내용은 조사 대상자의 일반적인 사항을 비롯하여 해외취업을 하 게된 동기, 해외취업 현황, 해외취업을 하게된 경로, 해외취업을 위한 준비항목, 해외취업 수행에 대한 중요도와 만족도 등 총 문항으로 구성되었다. . 통계처리 본 연구를 위해 수집된 자료는 데이터 코딩(coding) 및 클리닝 (cleaning) 과정을 거쳐 statistical package for social science (spss) v. 통계 패키지(ibm, usa)를 활용하여 분석하였다. 모든 문항은 빈도, 백분율을 활용하여 일차 분석되었고, likert scale을 적용한 문항은 평균값과 표준편차를 구해 비교 분석하였다. results and discussion . 연구대상자의 일반적 특성 연구대상자의 일반적 특성은 table 과 같다. 성별은 남자가 . %, 여자가 . %로 뷰티 산업의 특성상 여자 응답자가 대다 수였고, 연령은 워킹홀리데이 비자 발급이 가능한 세 이하가 . %로 가장 많았고 세 이상이 . %이었다. 응답자의 대학 전 공은 피부미용이 . %로 가장 많았고, 헤어가 . %, 메이크업이 . %, 네일아트 . %, 기타가 . %이었다. 최종학력은 전문대졸 이 . %로 가장 많았으며 . %가 미혼이었다. 해외 근무국가는 호주와 뉴질랜드가 . %로 대다수를 차지하였고 중국, 일본 등 아시아가 . %이었다. park ( )의 연구에 의하면 뷰티학과 학 생들의 인턴쉽 및 취업 희망 국가는 북미(미국, 캐나다)가 가장 많 았고, 호주, 중국의 순이었으나 실제 뷰티 전공자의 해외근무지는 호주, 뉴질랜드가 대다수를 차지하여 희망국가와 실제 취업 및 인 턴쉽 국가는 차이가 있는 것으로 나타났다. 이는 현재 대부분의 대 학들이 졸업예정자를 대상으로 해외취업 및 인턴쉽을 진행하고 있 어 워킹홀리데이 비자 발급이 용이한 호주, 뉴질랜드 지역으로 집 중된 결과라 할 수 있다. 또한 미국, 캐나다 등 많은 국가에서 취업 table . employment status (n= ) categories items n % motivation various foreign cultural experiences . improving language skills . learning advanced practical skills . obtaining job experiences . supporting institution through university support programs . media . human resources development service of korea . job recruitment company . others . shop category by owner korean owned . locally owned . shop category by specialty skincare shop . hair shop . wedding shop . spa . nail shop . others . employment period less than six months . six months to less than one year . one year to less than two years . two years to less than three years . four years and over . monthly salary less than , , won . , , to , , won . , , to , , won . , , won and over . visa category working holiday visa . student visa . working visa . work experience and satisfaction among beauty graduates http://dx.doi.org/ . /ajbc. . 비자의 경우 학사학위 이상, 실무경력 – 년 이상의 경력자를 우대 하고 있어 현지취업 및 인턴쉽을 위한 비자 발급이 어려운 현실이 반영되었다 할 수 있다. . 근무상태 응답자의 해외인턴쉽 지원동기는 다양한 해외문화체험이 . % 로 가장 많았고 어학능력향상과 선진기술 습득이 각각 . %, 국내 취업 시 경력을 인정받기 위함이 . %로 가장 낮은 결과를 보였다 (table ). 이는 조리 및 외식관련 전공자를 대상으로 조사한 결과 선진문화 체험 및 견문확대, 해외선진실무기술 축적, 어학능력의 향상 순으로 나타난 choi et al. ( )의 연구결과와 유사하였다. 해외문화체험이나 어학능력이 주요 지원동기로 꼽힌 이유는, 국내 에 이미 년제 및 년제 미용관련학과가 개설되어 체계적인 교육 시스템을 구축하고 있으며(kang & choi, ), 국내 뷰티 기술에 대한 학생들의 자부심이 매우 높아 해외취업을 통해 선진기술을 습 득할 수 있다는 기대치가 낮기 때문이라고 할 수 있다. 또한, 실제 로 해외취업 경력이 국내 취업 시 전문분야 경력으로 인정되지 않 는 경향이 있어 경력인정에 대한 기대치도 낮음을 반영한 것이라 볼 수 있다. 그러나, 치위생사를 대상으로 한 yoo et al. ( )이 조 사한 연구에서는 해외취업의사가 있는 집단을 대상으로 조사한 경 우 주로 경제적 이득을 목적( . %)으로 해외취업을 고민하고 있 었고, 그 다음이 자아실현( . %), 업무의 질 향상( . %) 순으 로 나타나 본 연구와는 차이가 있었다. 응답자의 . %는 학교나 학과의 추천으로 졸업과 동시에 취업을 나간 경우였으며, . %가 한인 운영업체에서 근무한 것으로 나타났 다. 이는 전문기술 부족보다는 영어 등 현지 언어 능력의 부족으로 인 한 현지취업에 어려움이 있는 것으로 사료된다. yoo et al. ( )은 어 학능력 부족이 해외취업의 가장 큰 장애요소이므로 해외취업률 향상 을 위해 어학능력을 강화하는 것이 반드시 필요하다고 하였다. 해외취업 중 근무처는 피부관리실이 . %로 가장 많았고, 미용 실이 . %, 스파와 네일샵이 각각 . % 등 이었다. 이는 최근 의 료뷰티 관광산업과 더불어 피부미용분야의 해외진출이 활성화되고 의료서비스와 미용서비스의 결합으로 피부미용이 고부가가치 창출 이 가능한 분야로 자리매김한 결과라 할 수 있다(park, ). 해외취업 기간은 개월– 년이 . %로 가장 많았고, – 년이 . %, 개월 이하가 . %, – 년과 년 이상이 각각 . %이었 다. 해외취업 기간 중 평균 월수입은 – 만원이 . %로 대다 수를 차지하였고, – 만원이 . %, 만원 이하가 . %, 만원 이상이 . %이었다. kwak & song ( )의 연구결과에 의 하면 국내 뷰티 산업 종사자의 경우 급여 만원 이하가 . %, – 만원이 . %로 가장 많은 결과를 보여 국내 급여수준 과 해외현지 급여수준에 차이가 없는 것으로 나타났다. 이는 국내 의 최저시급이 지속적으로 상승한 결과이기도 하지만 해외현지에 서 한인업체에 주로 취업하고 있어 봉급수준이 타업종에 비해 낮 은 결과로 사료된다. 해외취업 중 비자상태는 워킹홀리데이 비자가 . %로 가장 많았고, 학생 비자가 . %이었으며 정식 워킹 비자 를 발급 받아 취업한 경우는 . % 뿐이었다. . 사전교육현황 해외취업을 위해 받은 교육훈련기간은 개월 이하가 . %로 가장 많았고 개월 이하가 . %, 년 이상이 . %로 가장 낮은 결 과를 보였다(table ). 반면, 응답자들이 생각한 필요한 교육훈련 기간은 개월 이하가 . %로 가장 많았고 개월 이하가 . %로 나타나 실제 받은 기간과 유사하였으나 년 이상의 장기 교육훈련 이 필요하다고 응답한 사람이 . %로 나타났다. 해외취업과 관련 하여 받은 교육은, 어학 중심교육이 . %로 가장 높았고, 직무중 심교육이 . %, 서비스매너교육 및 자격증과정이 . %, 현지문 화교육 . %의 순으로 나타났다. kwon & kim ( )은 어학교 table . pre-job training (n= ) categories items n % received pre-job training period one month or less . three months or less . six months or less . one year or less . over one year . recommended training period for respondents one month or less . three months or less . six months or less . one year or less . over one year . types of pre-job training language training . practical skill training . foreign cultural preparation . service manner training . obtaining licenses . 뷰티 전공자의 해외취업 실태 및 만족도에 미치는 요인 http://www.e-ajbc.org 육의 경우 취업 시 즉시 사용할 수 있는 현장중심의 어학교육을 실 시하는 것이 필요하다고 하였으며, 해외취업 및 인턴쉽의 필요성과 함께 글로벌 마인드를 심어 주어 글로벌 시대에 맞는 현실에 대한 인식과 미래비전을 심어줄 필요가 있다고 하였다. . 가장 도움이 된 사전교육 응답자가 해외취업에 도움이 되었다고 밝힌 교육훈련 중 어학교 육이 순위로 . %로 가장 많았고 직무교육이 . %, 산업체 현 장실습이 . % 순이었다. 현지문화교육은 . %로 가장 낮은 결 과를 보였다(table ). 순위로는 현지문화교육이 . %, 서비스매 너교육이 . %, 산업체 현장실습이 . %이었다. 전체 응답자의 . %가 어학교육이 해외취업에 도움이 된다고 선택하였고, . % 가 직무교육, 응답자의 . %가 서비스매너교육을 선택하였다. 이는 해외인턴쉽 이수를 위한 가장 중요한 선수과목에 대한 설문에 외국어, 실무관련 교과목, 커뮤니케이션 기법 그리고 해외문화관 광 순으로 나타난 kim ( )의 연구와 유사한 결과이다. . 직무수행시 가장 중요한 요소 해외취업 시 업무 수행에 있어서 중요한 요소는 무엇인지를 점 척도로 조사한 결과(table ), 전공실무가 . ± . 로 가장 중요 도가 높았고 급여소득이 . ± . , 근무시간이 . ± . , 산 업체 환경이 . ± . 의 순으로 나타났다. 이외 기숙사 등 복 지시설, 개인 발전을 위한 투자의 순이었으며 승진이 . ± . 로 가장 낮은 결과를 보였다. 뷰티의 경우 현지취업 시 가장 우선 되는 것이 실무기술이며 급여소득이나 근무시간, 산업체 근무환경 등의 중요도가 높게 나타났으며 이는 조리 외식전공자를 대상으로 한 해외취업 수행의 중요도에 관한 조사에서 언어( . ), 부서간의 협력( . ), 대인관계( . ) 순으로 중요도가 높게 나타난 choi et al. ( )의 연구와는 다른 결과이다. 이는 뷰티 전공자들이 주로 취업 을 하는 현지 한인산업체들이 소규모인 경우가 대부분이고 직원이나 부서간의 협력 작업보다는 개인 작업을 주로 하는 뷰티업무의 특성 과 관련있다. 또한 산업체내 체계적인 승진시스템이나 직급체계가 구축되어 있지 않아 승진에 대한 기대치가 낮은 결과라 할 수 있다. . 해외취업에 만족하는 이유 해외취업과 관련하여 만족하는 이유를 복수 선택하게 하였을 때(table ), 해외 선진문화 체험의 기회에 대한 만족도가 . % 로 가장 높았고, 외국어능력 향상이 . %, 선진실무기술 습득 table . the most helpful pre-job training (n= ) categories st priority nd priority rd priority sum ) n % n % n % n % language training . . . . practical skills training . . . . foreign cultural preparation . . . . service manner training . . . . practicum at shops . . . . obtaining licenses . . . . ) sum, total number and percentage of st, nd, and rd. table . important factors influencing job performance (n= ) categories very important important neutral less important least important average sd ) n % n % n % n % n % practice relevance . . . . . . . size of shop (company) . . . . . . . work environment . . . . . . . work cooperation . . . . . . . working hours . . . . . . . personal development . . . . . . . salary . . . . . . . promotion . . . . . . . welfare (medical insurance etc.) . . . . . . . welfare (accommodation) . . . . . . . ) sd, standard deviation. work experience and satisfaction among beauty graduates http://dx.doi.org/ . /ajbc. . 이 . %로 그 다음이었다. 이는 해외취업 동기를 묻는 질문에서 (table ), 선진기술 습득이나 어학능력향상이 각 . %로 낮아 주 요 지원동기가 아니었던 것에 비하면 취업 후 매우 높아진 것으로 해외취업이 외국어능력 향상과 선진기술 습득의 기회를 제공하였 음을 의미한다고 볼 수 있다. 또한 봉급 등 경제적 보상이 . %, 해외이민의 기회 제공에 대한 만족도가 . %으로 나타나 해외취 업이 일정 정도 이민의 기회로 이어지고 있음을 나타낸다고 볼 수 있다. 해외 선진문화 체험의 기회에 대한 만족도가 가장 높은 것 은 해외인턴쉽 성과 변인 중 참여자 만족도에 통계적으로 유의한 수준으로 영향을 주는 변인은 ‘상관 및 동료와 적극적 의사소통’ 요인과 ‘외국문화의 적극적 체험’ 요인인 것으로 나타난 bae et al. ( )의 연구와 유사하다고 할 수 있다. . 해외취업에 불만족한 이유 해외취업과 관련하여 불만족한 이유를 복수 선택하게 하였을 때 (table ), 기숙사 등 복지제도의 부족이 . %로 높았으며 봉급 등 경제적 보상이 . %, 국내 취업 시 경력인정이 안됨이 . % 로 그 다음이었다. 해외에서 취업 시 언어능력의 부족 등으로 한 인운영 산업체에 취업하는 경우가 대부분을 차지하여 기숙사 등 직원복지시설에 대한 지원이 부족하고 봉급수준도 현지 최저시급 기준에 미치지 못하는 경우가 있어 타업종 대비 근무조건이 떨어지 는 경우가 많은 것으로 파악된다. 또한 귀국 후 국내 산업체 취업 시 해외근무경력이 인정받지 못하는 경향이 있으며, 특히 헤어 전공인 경우 산업체에서 자체 승급제도를 통해 디자이너를 양성하고 있어 해외취업자의 경우 경력이 인정받지 못하는 경향이 있다. 해외취업 확대를 통한 글로벌 선진인력 양성을 위해 해외 현지의 우수한 취업 처 개발과 함께 산업체와 대학간의 협약을 통해 해외취업 경력을 적 극적으로 인정하는 방안을 마련하기 위한 노력이 이루어져야한다. conclusion 본 연구는 뷰티 전공자의 해외취업 실태를 조사하고자 설문조사 를 실시하였으며 조사 결과는 다음과 같다. 첫째, 조사대상자의 성별은 여자가 . %, 연령은 세 이하가 . %로 대부분을 차지하였다. 전공은 피부미용이 . %, 헤어미 용이 . %, 메이크업, 네일아트, 기타가 각 . %이었다. 해외근 무국가는 호주, 뉴질랜드가 . %로 대다수를 차지하였고, 중국, 일본 등 아시아가 . %이었다. 둘째, 해외취업의 지원동기는 다양한 해외문화체험이 . %로 table . factors influencing job satisfaction (multiple choices possible) (n= ) categories agreed n % learning advanced practical skills . improving language skills . economical gain (salary) . opportunity for immigration . good welfare (including accommodation) . social perception regarding beauticians . opportunity for foreign cultural experiences . preferential treatment when getting a job in korea . table . factors influencing job dissatisfaction (multiple choices possible) (n= ) categories agreed n % lack of opportunity for learning advanced practical skills . lack of opportunity for improving language skills . low economical gain (salary) . lack of immigration opportunities . unsatisfactory welfare (including accommodation) . social perception regarding beauticians . cultural differences (racism) . work experience is not recognized when getting a job in korea . 뷰티 전공자의 해외취업 실태 및 만족도에 미치는 요인 http://www.e-ajbc.org 가장 많았고, 지원기관은 학교 및 학과가 . %로 대다수를 차지 하였다. 해외 근무처는 한인 운영산업체가 . %이었고, 피부관 리실이 . %, 미용실이 . %이었다. 해외취업 기간은 개월– 년이 . %로 가장 많았고 – 년이 . %이었다. 평균 월수입은 – 만원이 . %, – 만원이 . %이었다. 해외취업 중 비 자상태는 워킹홀리데이 비자가 . %, 워킹비자가 . %이었다. 셋째, 해외취업을 위해 받은 교육훈련기간은 개월 이하가 . % 로 가장 많았고 개월 이하가 . %이었다. 이는 응답자가 답한 해 외취업에 필요한 교육기간과 거의 일치하였다. 취업 전 . %가 어 학중심교육을 받았으며, 그 외 직무중심교육( . %), 서비스매너교 육( . %)과 자격증과정( . %) 등을 받았다고 응답했다. 넷째, 해외취업에 가장 도움이 된 교육내용 중 순위로 선정 된 항목은 어학교육( . %), 직무교육( . %), 산업체 현장실습 ( . %) 등 이었고, 순위는 현지문화교육( . %), 서비스매너교 육( . %), 산업체 현장실습( . %) 등 이었다. 전체적으로는 응답 자의 . %가 어학교육이 가장 도움이 된다고 했으며, 직무교육 ( . %), 서비스매너교육( . %) 순이었다. 다섯째, 응답자가 답한 해외취업 시 업무 수행에 있어서 중요한 요소는 전공실무가 . ± . 로 가장 높았고, 급여소득이 . ± . , 근무시간이 . ± . , 산업체 환경이 . ± . 의 순으 로 나타났다. 이외 기숙사 등 복지시설, 개인 발전을 위한 투자의 순이었으며 승진이 . ± . 로 가장 낮은 결과를 보였다. 여섯째, 해외취업에 대해 만족하는 이유는 해외 선진문화 체험 . %, 외국어 능력 향상이 . %로 가장 높게 나타났고, 해외취 업에 불만족한 이유는 기숙사 등 복지제도가 . %로 가장 높았 고, 봉급 등 경제적 보상이 . %, 미용인에 대한 사회적 인식이 . %, 해외이민 등 기회제공 부족이 가장 낮은 . %로 나타났다. 본 연구는 기존의 해외취업 관련 연구가 대부분 취업 희망자를 대상으로 조사한 반면, 뷰티 전공자 중 해외취업을 하고 있거나 다 녀온 자를 대상으로 하여 실제 경험을 바탕으로 한 해외취업 실태 를 파악한 점에서 그 의의가 있다. 그러나 뷰티 전공 해외취업자가 현 시점에 많지 않고 졸업 후 소재 파악이 쉽지 않는 여건으로 인하 여, 연구대상이 한정적이어서 조사결과를 일반화 하기에는 무리가 있다. 향후 글로벌 역량 증진과 해외취업처 발굴 및 취업 증진을 위 해 전공별 해외취업 실태 조사 등 지속적인 연구를 통해 해외취업 자에게 필요한 어학교육 및 현지 직무능력교육 등의 다양한 프로그 램을 구축하여 제공하는 노력이 필요하다. references bae sg, lee h, chung jy. investigation into the influential factors on outcomes of college students’ overseas internship. the journal of korean education , : - , . chin ch. status and prediction on beauty service industry in korea. asian journal of beauty and cosmetology, : - , . cho es, lee yd, lee jg, chung js. analysis on the overseas internship of korean college students and policy implications. journal of employment and career, : - , . choi yh, kim is, kim sy. evaluation of the perception and satisfaction of working and internship abroad: by undergraduates studying in culinary and foodservice departments. journal of the east asian society of dietary life, : - , . jeon ss. the effects of aesthetician’s environment and satisfaction on professional consciousness. asian journal of beauty and cosmetology, : - , . jun ys. effective approaches of hotel and beauty business in japanese market. journal of japanese culture, : 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development quarterly, : - , . park sm. beauty school students’ perceptions of overseas internships and employment and their preparation behavior for employment: focusing on university or college women in daegu. journal of investigative cosmetology , : - , . yoo jh, kim yj, noh hj. intention of overseas employment in korean dental hygienists. journal of korean society of dental hygiene, : - , . 뷰티 전공자의 해외취업 실태 및 만족도에 미치는 요인 http://www.e-ajbc.org 국문초록 뷰티 전공자의 해외취업 실태 및 만족도에 미치는 요인 정은영 , 박미영 * 제주한라대학교 뷰티아트과, 제주도 제주시, 한국 제주한라대학교 간호학과, 제주도 제주시, 한국 목적: 본 연구의 목적은 뷰티를 전공한 해외취업자의 현황을 파악하고 만족도에 영향을 미치는 요인들을 조사하여 참가자들의 현실 적 요구 등에 기반한 지원방안을 도출하기 위한 기초 자료를 마련하기 위함이다. 방법: 국내 개 대학의 뷰티 전공 해외취업 참가자 를 대상으로 년 월부터 개월간 설문조사를 실시하였으며, 응답률은 %를 기록하였고, 총 부가 최종 분석에 사용되었다. 결과: 본 연구의 응답자의 대부분이 여자( . %)이며, 세 이하( . %)였다. 피부미용 전공( . %)이 헤어미용( . %) 전공자보 다 다수이었으며, 근무국가는 호주, 뉴질랜드가 . %로 대다수를 차지하였다. 주된 해외취업의 지원동기는 다양한 해외문화체험 ( . %)이었으며, 대부분( . %)이 학교 및 학과의 지원을 통해 해외취업에 참여하게 되었다. 주로 한인 운영산업체( . %)에 취업하 였으며, 취업기간은 개월– 년 이하( . %)가 가장 많았다. 해외취업을 위해 받은 교육훈련기간은 개월 이하가 . %로 가장 많았 다. 취업 전 . %가 어학중심교육을 받았으며, 응답자의 . %가 어학교육이 가장 도움이 되었다고 답하여 취업 전 충분한 어학준비 의 필요성이 강조되었다. 해외취업 시 업무 수행에 있어서 전공실무능력( . ± . )이 가장 중요한 요소로 꼽혔으며, 해외 선진문화 체험( . %)과 외국어 능력 향상( . %)의 기회가 만족도와 연결되었다. 결론: 본 연구는 기존의 해외취업 관련 연구가 대부분 취업 희망자를 대상으로 조사한 반면, 뷰티 전공자 중 해외취업을 하고 있거나 다녀온 자를 대상으로 하여 실제 경험을 바탕으로 한 해외취 업 실태를 파악한 점에서 그 의의가 있다. 향후 지속적인 연구를 통해 해외취업자에게 필요한 어학 및 현지직무능력 교육 등의 다양한 프로그램이 구축되어야 할 것이다. 핵심어: 뷰티 전공자, 해외취업 경험, 취업준비 훈련, 만족도, 어학교육 참고문헌 강수경, 최근희. 국내 대학의 미용관련학과 및 인력 배출 현황 분석. 한국미용학회지, : - , . 강주아, 이영주. 미용업 종사자의 성취동기와 직무성과의 관계 연구. 한국미용학회지, : - , . 곽기숙, 송연숙. 한국 헤어미용 서비스산업 종사자들의 직무만족요인과 직업만족도 및 이직의도와의 관계. 한국미용학회지, : - , . 권경득, 강일규, 임정빈. 해외취업의 활성화 방안에 관한 연구: 청년 해외취업을 중심으로. 한국정책과학학회보, : - , . 권경득, 김덕준. 청년 인적자원의 해외취업 활성화 방안에 관한 연구: 인식조사를 중심으로. 한국인사행정학회보, : - , . 김신영, 김용련. 대학의 글로벌 인재 양성 및 해외취업 활성화를 위한 교육프로그램의 현황 분석 연구. 교육평가연구, : - , . 김영규. 해외인턴십을 활용한 지방 년제 대학 여성인력의 취업 활성화 방안. 관광연구, : - , . 김임선, 김정숙. 치기공과 학생들의 해외취업에 대한 선호도 조사. 대한치과기공학회지, : - , . 박선민. 뷰티학과 학생들의 해외인턴십 및 해외취업에 대한 인식과 취업준비 행동: 대구소재 여대생을 중심으로. 대한미용학 회지, : - , . 배성근, 이희숙, 정제영. 대학생 해외 인턴십 성과에 대한 영향 요인 분석. 한국교육, : - , . 유자혜, 김영진, 노희진. 치과위생사의 해외취업의사에 영향을 미치는 요인. 한국치위생학회지, : - , . work experience and satisfaction among beauty graduates http://dx.doi.org/ . /ajbc. . 이은주, 손정태. 병원간호사의 해외취업 의향에 영향을 미치는 요인. 간호행정학회지, : - , . 이황원. 글로벌 인재 양성을 위한 대학생 해외인턴십의 성공요인 분석. hrd연구, : - , . 전승신. 피부관리사의 직무환경과 직무만족도가 직업의식에 미치는 영향. 아시안뷰티화장품학술지, : - , . 전윤선. 호텔·뷰티 분야를 중심으로 일본 고용시장의 효율적인 접근방안. 일본문화학보, : - , . 정은영, 박미영. 피부미용사의 간호조무사 자격 취득에 따른 업무실태 조사. 아시안뷰티화장품학술지, : - , . 조은상, 이영대, 이종구, 정지선. 한국 대학생들의 해외 인턴쉽 활성화를 위한 탐색적 연구. 취업진로연구, : - , . 진정화. 한국 뷰티서비스 산업의 현황과 예측. 아시안뷰티화장품학술지, : - , . 최영희, 김일순, 김수연. 해외 취업 및 인턴쉽에 대한 인식과 만족도에 관한 연구. 동아시아식생활학회지, : - , . 뷰티 전공자의 해외취업 실태 및 만족도에 미치는 요인 http://www.e-ajbc.org 中文摘要美容专业毕业生的海外就业实况及满意度因素鄭恩英，朴美英 * 濟州漢拏大學美容學科，濟州島濟州市，韩国濟州漢拏大學看護學科，濟州島濟州市，韩国目的: 调查美容专业毕业生的海外就业情况，并确定海外就业满意度影响因素，最终导出应答者的现实要求为基础的支援方案，提出基础资料。方法: 以四所韩国大学的美容毕业生为研究对象，从年月开始进行为期个月的问卷调查，回答者中包含至少有在国外工作过一次的经历或目前在国外工作。回答率为 %，最终对份问卷调查进行分析。结果: 大多数应答者为女性占 . %，其中年龄小于岁占 . %。皮肤美容专攻（ . %）多于美发专攻（ . %），其中大部分（ . %）在澳大利亚和新西兰工作。海外就业的主要动机是体验外国文化，大部分毕业生（ . %）是通过学校以及学科的支援参加海外就业。在海外主要工作地点为韩国人运营的产业，占 . %，就业期间为个月到年以下占 . %，年以上占 . %。此外，为了在海外就业， . %的大多数应答者接受岗前培训，其期间为个月或更少， . %的应答者不到个月。这个调查结果与应答者答复的海外就业培训期间一致。大多数（ . %）的应答者参加了语言培训，其中 . %的应答者回答语言培训最有帮助，强调了就业前语言培训的必要性。海外就业时，专攻实务能力为最重要的因素。外国文化经验（ . %)和语言技能的提高（ . %)与海外工作经验满意度因素相关。与此相反，不满因素大多数（ . %）与住宿等缺乏福利相关，其次为低工资（ . %）等经济问题。结论: 本次研究如同其他海外就业相关研究，以求职者为研究对象，同时在美容专业者中以以前工作过或目前在海外工作为研究对象，以实际经验为基础调查了海外就业状况，这种调查显示重大意义。未来通过持续的研究对海外就业者提供必要的语言及职能教育。关键词: 美容专业者，海外就业经验，岗前培训，满意度，语言教育 humanitiesoct --la:layout cmaj • october , • ( ) © canadian medical association or its licensors humanities which cemetery? who has to be notified? the decisions were endless. the first question that should be asked, the first of those many decisions to make should be: would your loved one have wanted to be a tissue donor? coincidentally, brad and i had dis- cussed donation shortly before his death. i asked him if he would want to be listed as a donor. “absolutely,” he said, and gave me that easy smile of his. “mom,” he said, gesturing to his body, “this is only a rental.” i cannot describe the comfort of knowing that my son’s eyes continue to see the world, although through a different lens. the games of rugby he so loved to play will continue with the gift of tendons into another ath- lete or weekend warrior. heart valves will save the life of a child with a heart defect. the gift of organ and tissue dona- tion can give another dimension of meaning to a life too briefly lived: a n e w b o r n b a b y , a p r e s c h o o l e r , a teenager. it gave my family comfort, a n d y e s , t h e g i f t o f a l e g a c y f o r brad’s life, and a source of comfort to a grieving mother and a devastated family. brad gave so much in life and to life and i want him to be remembered. not the tragedy that was his death, but the gift that was his life. through the privi- lege of donation, it was a gift that we shared with others, when his heart could no longer beat. our lives were incredibly enriched by brad’s life and love. it is my belief that in the lives of those transplant recipients, as they go on to live and love, there is a legacy. and when they laugh, i’m sure there is an echo to brad’s spirit. and he is smiling. denice klavano mother halifax, ns ms. klavano is the certified tissue bank specialist at the regional tissue bank, capital district health authority in halifax, ns. she collected her first scar as a child. a careless uncle stepped on her pinky, pressing it into a permanent but gentle hook. scalding water and burning pans have thickened skin, dulled nerves. we screamed in the bathtub, feet on fire her hands swirling in lava, coaxing us. her joints are swelled, hard now. the wedding solitaire sleeps in its velvet crevice; she took it off before it strangled her. its replacement, with clustered sapphires, a spider’s cataracts, shines dully from caked ivory soap. now her thumbs hook the steering wheel. the fingers hang in involuntary curves, scalloped and pink, pointing rudely to the pedals and feet that have forgotten which way to push. lydia kang md general internal medicine university of nebraska medical center nebraska, usa poem they were beautiful once © j u p it e ri m a g e s c o rp . d o i: . / cm aj . << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /all /binding /left /calgrayprofile (dot gain %) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /warning /compatibilitylevel . /compressobjects /tags /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /leavecolorunchanged /dothumbnails false 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/monoimageminresolutionpolicy /ok /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /description << /chs /cht /dan /deu /esp /fra /ita /jpn /kor /nld (gebruik deze instellingen om adobe pdf-documenten te maken voor kwaliteitsafdrukken op desktopprinters en proofers. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /ptb /suo /sve /enu (use these settings to create adobe pdf documents for quality printing on desktop printers and proofers. created pdf documents can be opened with acrobat and adobe reader . and later.) >> /namespace [ (adobe) (common) ( . ) ] /othernamespaces [ << /asreaderspreads false /cropimagestoframes true /errorcontrol /warnandcontinue /flattenerignorespreadoverrides false /includeguidesgrids false /includenonprinting false /includeslug false /namespace [ (adobe) (indesign) ( . ) ] /omitplacedbitmaps false /omitplacedeps false /omitplacedpdf false /simulateoverprint /legacy >> << /addbleedmarks false /addcolorbars false /addcropmarks false /addpageinfo false /addregmarks false /convertcolors /noconversion /destinationprofilename () /destinationprofileselector /na /downsample bitimages true /flattenerpreset << /presetselector /mediumresolution >> /formelements false /generatestructure true /includebookmarks false /includehyperlinks false /includeinteractive false /includelayers false /includeprofiles true /multimediahandling /useobjectsettings /namespace [ (adobe) (creativesuite) ( . ) ] /pdfxoutputintentprofileselector /na /preserveediting true /untaggedcmykhandling /leaveuntagged /untaggedrgbhandling /leaveuntagged /usedocumentbleed false >> ] >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice westminsterresearch http://www.westminster.ac.uk/westminsterresearch truth, good and beauty: the politics of celebrity in china sullivan, j. and kehoe, s. this journal article has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by cambridge university press in china quarterly. this version is free to view and download for private research and study only. not for re-distribution, re-sale or use in derivative works. © cambridge university press, the final definitive version in the online edition of the journal article at cambridge journals online is available at: https://dx.doi.org/ . /s the westminsterresearch online digital archive at the university of westminster aims to make the research output of the university available to a wider audience. copyright and moral rights remain with the authors and/or copyright owners. whilst further distribution of specific materials from within this archive is forbidden, you may freely distribute the url of westminsterresearch: ((http://westminsterresearch.wmin.ac.uk/). in case of abuse or copyright appearing without permission e-mail repository@westminster.ac.uk https://dx.doi.org/ . /s http://westminsterresearch.wmin.ac.uk/ repository@westminster.ac.uk truth, good and beauty: the politics of celebrity in china jonathan sullivan* and séagh kehoe† abstract a visit to a chinese city of any size – looking up at downtown billboards, riding public transport, shopping at a mall – is to be in the presence of a chinese celebrity endorsing a product, lifestyle or other symbols of “the good life.” celebrity in china is big business, feeding off and nourishing the advertising-led business model that underpins the commercialized media system and internet. it is also a powerful instrument in the party-state’s discursive and symbolic repertoire, used to promote regime goals and solidify new governmentalities through signalling accepted modes of behaviour for mass emulation. the multi- dimensional celebrity persona, and the public interest it stimulates in off-stage lives, requires an academic focus on the workings of celebrity separate to the products that celebrities create in their professional roles. the potential to connect with large numbers of ordinary people, and the emergence of an informal celebrity-making scene in cyberspace symptomatic of changing attitudes towards fame among chinese people, marks the special status of celebrity within china’s constrained socio-political ecology. the motivation for this article is to further scholarly understanding of how celebrity operates in china and to bring this expression of popular culture into the broader conversation about contemporary chinese politics and society. keywords: celebrity; internet; media; pop culture; fame; politics celebrity images pervade the public spaces and private screens of contemporary china. the “exorbitant visibility of all kinds of celebrities” is testament to the maturation of a celebrity industry that feeds off and nourishes the advertising-led business model underpinning the media system and internet. despite its increasing ubiquity, the aura of frivolousness that surrounds celebrity perhaps explains why “chinese stars and stardom rarely receive sustained academic attention.” while the professional milieux of film, music and popular culture that many celebrities inhabit are recognized and closely studied sites of political and cultural power, negotiation and contestation, the contours of chinese celebrity remain relatively uncharted. this is a significant gap. the capacity to reach substantial audiences and potentially influence society have made individual celebrities and the industry that creates and promotes them subject to a system of control and instrumentalization by the state. celebrity culture is a powerful instrument in the state’s discursive and symbolic repertoire, used to promote the regime goals of orderly progress towards a modern society under the leadership of the communist party. the chinese celebrity scene is characterized by contradictions. the industry is thriving, despite stringent circumscriptions applied by state and industry actors. celebrity culture in china can be superficial, yet it retains a strong moral component. despite the growing attraction and ease with which ordinary people can achieve celebrity status online, celebrity * china policy institute, school of politics and ir, university of nottingham. email: jonathan.sullivan@nottingham.ac.uk (corresponding author). † school of politics and ir, university of nottingham. email: seagh.kehoe@nottingham.ac.uk. guo , . farquhar and zhang , . berry and farquhar ; zhu and berry . exceptions include edwards and jeffreys ; hood . file:///c:/users/kehoes/downloads/jonathan.sullivan@nottingham.ac.uk mailto:seagh.kehoe@nottingham.ac.uk remains a “systematically hierarchical and exclusive category,” and the state, via the media and cultural industries, retains control of the symbolic economy in which it operates. by analysing official documents from state institutions responsible for managing china’s culture industry, chinese media discourse and online platforms, this article traces the development of the celebrity industry in china, before discussing how and why the state attempts to control its parameters and individual celebrity conduct. it then shows how the state tries to harness celebrity as a vehicle for promoting socialist values and patriotism. finally, the article identifies the emergence of an informal celebrity-making scene in cyberspace symptomatic of changing attitudes towards fame among chinese people, but not the state: identified as potentially subversive, the state has moved quickly to exert control over streaming platforms promising “celebritization of the ordinary.” the emergence of china’s celebrity industry we understand celebrity as a multidimensional quality, the sum of an individual’s product and packaging, personal attributes and life beyond the professional realm. it is the celebrity persona, “a crafted and consolidated public projection of the real person, built in part out of film roles and other public appearances,” that distinguishes celebrity from mere well-knownness. celebrity comes in numerous forms, from “stars,” the sub-group at the apex of the celebrity hierarchy, to “celetoids,” ordinary people who become famous for a short time due to particular acts or circumstances. celebrities can be found across diverse professional sectors, from journalists and artists to businesspeople and athletes. the highest concentrations of celebrities, and the major constituent of the celebrity industry and culture, are the performing arts, notably film and music. while china has a long history of literary, musical and folk heroes in the imperial and modern eras and concerted efforts were made to create “socialist stars” during the mao era, the contemporary celebrity scene is a product of processes associated with the emergence of market socialism in the reform era. economic reforms and urbanization, increasingly widespread prosperity and the associated rise of consumerism, commercialization of the media and technological change, the growth of individualism and decline of collectivist ways of life have all contributed to the supply and demand for celebrities. central on the supply side was the emergence of a media and entertainment system combining control with commercialization, which created the dual constituencies of the public and the state by removing state subsidies while maintaining restrictions on permissible content. in response, the media and entertainment industries were forced to adopt advertising- led business models while keeping their output within deliberately vague, post-hoc and moving boundaries set by the state. consciously apolitical soft entertainment formats were embraced as a way of achieving both ends, with substantial demand from chinese audiences accustomed to a diet of ideologically-driven “edutainment.” expanded media and entertainment scenes provided opportunities for celebrity creation, with actors and singers from hong kong and rojek , . turner . shingler , . rojek . mcdermott . cheek . zhao . stockmann . donald et al. ; wen . taiwan (gangtai 、、) leading the way. over time, the various components of the celebrity industry, including advertising, public relations (pr; gonggong guanxi 、、、、 ) and entertainment media have expanded and professionalized their operations. official state media outlets such as xinhua (aa), people’s daily (renmin ribao aaaa) and global times (huanqiu shibao aaaa), as well as leading commercial web portals feature extensive entertainment (yule a a ) sections replete with celebrity images, features and gossip. popular magazines like southern metropolitan entertainment weekly (nandu yule zhoukan aaaaaa), entertainment weekly (yule zhoukan aaaa) and star weekly (xing zhoukan aaa) regularly feature interviews with celebrities, reviews of popular culture and commentary pieces on entertainers. individual celebrity and celebrity-centred accounts on chinese social media attract audiences in the tens of millions. the photographer anointed by global times as “china’s number one paparazzo” (gouzai aa), zhuo wei aa, has several million followers on weibo. absent during the mao era, celebrity advertising endorsements returned to china in when actress pan hong 、、 and actor li moran 、、、 appeared in advertisements for cosmetics and medicines respectively. subsequently, endorsements with foreign and domestic brands became a lucrative business for chinese celebrities. there are now hundreds of chinese advertising agencies and transnational advertising agencies operating as joint ventures, and “a majority of advertising campaigns feature celebrities”. chinese celebrities endorse everything from precious gems to household goods, with some individuals representing more than different brands. chinese celebrities like the actresses li bingbing 、、、 and zhou xun 、、 and olympian liu xiang 、、 have gained global recognition as representatives for gucci, chanel and nike respectively. increasingly, endorsement deals, film roles and recording contracts are facilitated through studios or agencies such as the huayi brothers (huayi xiongdi chuanmei 、、、、、、) film and media conglomerate. since the first pr department was set up in by state-owned pharmaceuticals firm guangzhou baiyunshan 、、、、、 , hundreds of chinese pr firms, including joint ventures with major american companies like edelman and ogilvy, have been established. as china’s pr industry continues to grow rapidly, degrees in western-style pr are popular offerings at chinese universities. for these firms and practitioners to succeed in china’s pr industry, “cooperation and communication ties with government departments at all levels” is of critical importance. the major incubators for the performing arts and sports talent pools are the state- academies. here, at these key sites for cultivating china’s future actors and musicians, children identified as having talent receive stringent training and political education. of the top earning chinese performing artists identified by forbes magazine, and the celebrities with the most web searches per chinese search engine baidu, more than three quarters attended a state conservatory, dance or drama academy. actresses gong li aa and zhang ziyi aaa were discovered by film director zhang yimou aaa, himself a graduate of the beijing film academy (beijing dianying xueyuan aaaaaa), while attending beijing’s central academy of drama gold . liao . sun . schimmelpfennig and hollensen , . hung et al., , . yan . wu , . flannery ; baidu. . “jinri yule mingren paihangbang” (today’s celebrity ranking), june, http://top.baidu.com/buzz?b= &fr=topbuzz_b . accessed june . http://top.baidu.com/buzz?b= &fr=topbuzz_b (zhongyang xiju xueyuan aaaaaa). action movie star jet li (li lianjie 、、、 ) honed his trademark martial arts skills at shichahai sports school in beijing, a state school informally known as “the cradle of olympic talents.” emergence from “within the system” (tizhinei aaa) is one of the characteristics of chinese celebrities and their academy training is a major source of performed or genuine gratitude towards the state and the work ethic they profess as professional performers. those who do not thank the state in the accepted way, like sports stars zhou yang 、、 and li na 、、, are exceptions and face public censure. controlling celebrity the chinese celebrity industry operates within an interlinked commercial, legal and political structure. guided by the central publicity department (zhongyang xuanchuan bu aaaaa), the ministry of culture (wenhua bu a a a ) (moc) and the state administration of press, publication, radio, film and television (guojia guangbo dianying dianshi zongju aaaaaaaa aa) (sapprft; formerly sarft) are the two key institutions that oversee celebrity-related affairs. the moc ultimately determines “who can perform and under what circumstances,” and plays a significant role in the selection of celebrities for ambassadorial roles and participation in state-organized expos, festivals and campaigns. sapprft has the power to determine celebrity appearances across the chinese media-scape, including prohibiting media from featuring “celebrities embroiled in scandals.” the cyberspace administration of china (cac; guojia hulianwang xinxi bangongshi 、、、、、、、、、、) actively manages celebrity- related content online, shutting down popular celebrity news and gossip accounts in june and urging host platforms like tencent and baidu to ensure a “healthy, uplifting environment for mainstream opinion.” studios and talent agencies can be punished by state regulatory bodies for their clients’ behaviour, incentivizing them to carefully manage the celebrities they represent, and giving rise to an increasing number of legal firms specializing in entertainment law (yulefa 、、、) providing background checks, risk assessments, and analysis of related state laws and policies. celebrity endorsements are closely monitored by the state administration of industry and commerce (guojia gongshang xingzheng guangli zongju aaaaaaaaaa) under its code of advertising ethics (guanggao huodong daode guifan aaaaaaaa). the national advertising law (guanggaofa 、、、 ), first launched in , was updated in to include endorser liability in response to problematic celebrity advertisements, such as the melamine-tainted infant formula, produced by the state-owned sanlu group (sanlu jituan 、、、、) and endorsed by actress deng jie 、、, which killed six children in . the regulatory frameworks governing the conduct of the celebrity industry are supplemented by informal, soft controls in the form of government pronouncements and state media editorials setting out norms and expectations. in , for instance, sapprft introduced a “pledge on professional ethics, self-discipline for personnel in press, publications, radio, film and television.” fifty organizations across the entertainment sector promptly signed hood , . china.org.cn. . “sarft bands media hyper on celebrity scandals,” april, http://www.china.org.cn/culture/ - / /content_ .htm. accessed june . qin . li, . gov.cn. . “zhonghua minzu gonghe guo guanggao fa (quanwen)” (advertising law of the people’s republic of china (full text), april , http://www.gov.cn/xinwen/ - / /content_ .htm. accessed october . http://www.china.org.cn/culture/ - / /content_ .htm http://www.gov.cn/xinwen/ - / /content_ .htm the pledge. speaking at the launch, actress fan bingbing 、、、 declared that “to be a good actor, one must first be a good person,” which notably included “abiding by the law” and promoting “truth, good and beauty.” a follow-up editorial in the people’s daily ( ) set out the rationale for regulating celebrity behaviours: as public figures, celebrities have a huge influence on society, and are often imitated by fans. although their social responsibility as public figures is not clearly stipulated, it is very much a moral issue (zhuyao zai daode cengmian 、、、、、、、). because they influence society, they have an even greater obligation to set an example (geng you yiwu zai daodeshang zuochu biaoshuai 、、、、、、、、、、、、), and standard for the moral direction of society. expectations about the morality of celebrity conduct and their personal “quality” (suzhi 、、) are not restricted to the state. as edwards and jeffreys note, chinese publics care deeply about “the moral virtue of prominent individuals.” normative values like filiality, faithfulness in marriage and the collective good are dominant social norms that celebrities are expected to conform to by the state, business and publics. transgressions such as drug use or sex scandals can result in celebrities being forced to issue public apologies, disqualification from awards or blacklisting from professional and endorsement roles. actor huang haibo 、、、, for instance, spent six months in “custody and education” in for soliciting commercial sex, reflecting upon release that “as a public figure, i failed as a role model.” conspicuous consumption that is deemed excessive by the authorities or the public also attracts censure, as actors angelababy (yang ying 、、 ) and huang xiaoming 、、、 discovered after their extravagant wedding ceremony in . while the celebrity sector is subject to circumscription and control, individual celebrities have used the affordances of their status to raise public awareness around lgbt issues, notions of chinese-ness and filiality. for instance, tv host jin xing 、、 has raised the profile of transgender issues, as news anchor chai jing 、、 did with pollution. celebrities also support social causes through philanthropy, advocacy and representation in formal political institutions like the cppcc, and as activists and social critics. the punishment of other celebrities, like outspoken government critic and celebrity businessman xue manzi 、、、 , demonstrates the fine line between celebrity activism and what the state regards as transgressive acts. harnessing celebrity the scholarly literature on celebrity in the west has established that there is nothing accidental in the way that celebrities are created. carefully mediated fabrications advanced via “chains of attraction” and representing “typical ways of behaving, feeling and thinking in contemporary canaves . , . zhou and whitla . wang . china digital times. . “minitrue: take celebrity groom off air,” october, http://chinadigitaltimes.net/ / /minitrue-take-celebrity-groom-huang-xiaoming-off-air/. accessed june . fung . hood ; jeffreys a. jeffreys b. strafella and berg a; b. rojek , . http://chinadigitaltimes.net/ / /minitrue-take-celebrity-groom-huang-xiaoming-off-air/ society,” celebrities symbolize modes of behaviour consistent with the goals of government and business. with notable exceptions, celebrities are generally symbols of system- acceptance and a demonstration that “the system rewards talent and cherishes upward mobility.” in china, the state, which has long promoted role models for their patriotism, heroism or exemplary role-fulfilment, uses celebrities as a vehicle for promoting nationalism, traditional virtues and the pursuit of modernity. it has identified celebrities as purveyors of “spiritual goods” (jingshen chanpin 、、、、 ), exhorting them to “perform conscientiously, behave respectfully” and “take the lead in setting an example” for society to follow. as stockmann and gallagher conclude in their article on chinese commercial media, the state has learned that popular vehicles can transmit political messages more effectively than “old-style propaganda.” possessors of “symbolic capital” derived from constant publicity and deliberately crafted personas, chinese celebrities have inherited the mantle of socialist role model, embodying accepted modes of behaviour for mass emulation. this includes exhibiting norms structured by class, gender and the “continuous striving and upward mobility” manifest in “middle class” consumption behaviours. the state’s expectations are established and enforced through a repertoire of formal, informal and delegated control mechanisms described in the previous section. under market socialism the state’s social engineering (shehui gongcheng 、、、、) and moral construction (daode jianshe 、、、、 ) projects increasingly take the form of “governmentalities” associated with neoliberal ideas on the management of individual conduct. as individual merit, material wealth and consumption have become the hallmarks of market socialist progress, elevating the “quality” and “civilization” (wenming 、、) of the chinese people has been identified as a prerequisite for an orderly and stable modern society under continued ccp rule. individual self-improvement and learning from role models are framed by the state via the media, entertainment and curricula as patriotic acts advancing national prosperity, unity and strength. the production and consumption of celebrity in china thus takes place in a discursive context in which “quality” and “civilization” symbolize prescribed ways of behaving that underpin hu jintao’s “harmonious and well-off society” and xi jinping’s “chinese dream.” yet, as brownell points out, the discourse around “quality” and “civilization” has displaced the responsibility for progress to individuals, while masking the class structure and other systemic inequities that determine their access to the fruits of development. reform era economic development and the partial retreat of the state from many areas of life have resulted in greater prosperity and the expansion of individual freedoms. yet, some scholars argue that the transition from socialist collectivism to competitive market socialism dyer , . marshal . rojek , . edwards and jeffreys . guancha. . “chunwan weihe bu yong ‘wudian’ yanyuan” (why spring festival does not need “tainted” actors), february, http://guancha.gmw.cn/ - / /content_ .htm. accessed march . , . bourdieu . evans . wallis . yu . jeffreys . tomba . . http://guancha.gmw.cn/ - / /content_ .htm has also created an ideological void. partially filled by a state-led “nationalist turn” post- , it is manifest in a nationwide religious resurgence, the re-establishment of clan and temple organizations and the state-sanctioned revival of elements of confucianism. the history of celebrity in the west is also closely associated with a “void,” created by the encroachment of alienating capitalist economic structures, the industrial production of culture and the contemporaneous decline in organized religion in the early th century. scholars identified an “affective deficit in modern life” where direct social contact is replaced by para- social relations with celebrities, who provide an “illusion of intimacy” and are subject to the projection of “fantasies of belonging and fulfilment.” recent research on fandom in china similarly suggests that celebrity engagement is a “vehicle for self-idealization and psychological reinforcement” and a site for identity and community formation. whether prompted by state discourse or an unguided response to changing economic and social conditions, there is widespread enthusiasm for self-improvement in china and chinese celebrities nourish the vogue for self-help or “success study” (chenggongxue 、、、 ) by portraying the value of hard work and learning in pursuit of a better life. from factory workers learning skills to move up the career ladder, rural migrants using technology to look and feel modern and urban, to petty bourgeois (xiaokang 、、 ) adopting symbols of middle-class lifestyles, self-improvement is a widespread endeavour. magazine stories and celebrities’ communications on social media frequently emphasize the sacrifices and work ethic needed to become a successful performer, athlete or businessperson. the message conveyed by celebrities is that the system rewards perseverance, cultivation of talent and broadly compliant behaviours. chinese celebrity is also “embedded within a ccp-led nationalistic project that encourages public pronouncements of unabashed patriotism,” with punishments and public abuse heaped on those associated with “unpatriotic acts.” actress zhang ziyi, whose global stardom is predicated on having become the “embodiment of the transformation of chineseness in the age of global modernity,” was criticized in state media for playing the paramour of a japanese man in memoirs of a geisha, a hollywood production of an american novel. zhang, a global ambassador for the special olympics, was accused of “betraying national loyalties” and subject to online abuse when naked images of her on set with japanese co-star ken watanabe were posted online. in , sarft banned media coverage of tang wei (、、), a chinese actress who starred in taiwanese director ang lee’s (li an 、、) lust, caution (se, jie 、 , 、 ), a film the central government said “glorified traitors and insulted patriots.” kipnis . rosen . chau . tsai . bell . horkheimer and adorno, . turner , . rojek , . zhang . turner , . wang . chang . qiu ; wallis . latham et al. . edwards and jeffreys , . kourelou , . numerous taiwanese celebrities like pop stars chou tze-yu (zhou ziyu 、、、 ) and a-mei (zhang huimei 、、、、have been compelled by their industry employers to issue apologies for waving the flag or singing the anthem of the republic of china. others, like hong kong cantopop singer denise ho (he yunshi 、、、 ) have been blacklisted by the ministry of culture for associations with the umbrella and sunflower movements or “pro-independence” opinions. for individual celebrities, studios, agencies and the brands they represent, the threat of denied access to the chinese market is economically significant and an incentive to moderate public pronouncements and avoid association with “sensitive” issues. by contrast, “celebrities who adhere to state ideals are rewarded handsomely.” fan bingbing, for example, has occupied the top position in forbes’ ranking of total annual income for chinese celebrities in each of the last three years, reportedly earned million yuan (£ . million) from film roles and endorsements in . celebritization of the ordinary? reality tv and the internet in western democracies like the us and uk, where ubiquitous celebrity culture has “colonized the expectations of everyday life,” turner characterizes the popularization of self-mediation and the celebritization of regular people via reality tv as a “demotic turn.” reflecting the broader entertainment industry in which it is situated, reality tv in china is a highly controlled environment with substantial barriers to the participation of ordinary people in the celebrity- making apparatus. commercial experimentation with reality tv was quickly contained by the state, as the case of hunan satellite tv’s super girl (chaoji nüsheng 、、、、) illustrates. after propelling amateur singers li yuchun aaa and zhang bichen aaa to stardom, super girl ended its three-series run in , when sarft, party officials and state media denounced “the vulgar inclination of entertainment programs,” which contravened the pedagogical role fundamental to the media and cultural industries. unlike in the west, where extreme behaviours are encouraged, the undergrown chinese reality tv scene is closely controlled to ensure it reflects traditional values. in consequence, family-oriented shows like dad is back (baba huilai le 、、、、、) and where are we going dad? (baba qu nar? 、、、、、?) have competed with earnest dating shows like if you are the one (feicheng wurao 、、、、), where contestants displaying unseemly attitudes like materialism attract public and media criticism. despite careful management, even these shows have fallen foul of saaprft. in chinese cyberspace, which despite an effective censorship regime is still a comparatively free space, there is evidence of an emerging “demotic” celebrity sphere where ordinary people “turn themselves into media content through celebrity culture.” the rise of “me-casting” technologies, the attraction of going viral and the quest for external validation through the accumulation of likes and followers on social media has popularized the pursuit of online celebrity (wanghong 、、). this includes the “camgirls” who nurture followings through huang . hood , . flannery . turner , . . miao , . keane . keane and zhang . sullivan . turner , . online streaming sites, to bloggers and vloggers like exercise guru zhang jingqi 、、、 and idiosyncratic gaming critic yi xiaoxing 、、、. reflecting early criticism of the inauthenticity of celebrity, there are also people “well-known for their well-knownness,” celetoids like guo meimei 、、、 or zhang zetian 、、、 , ordinary people whose short-lived celebrity arrived “accidently.” rojek describes “the accelerated commodity life cycle of the celetoid” as an “industrial solution” to the problem of satisfying media and audience demands for consuming and pursuing celebrity. there is clearly abundant supply and demand: more than dedicated streaming companies serve an audience of over million people, per cent of whom view live chat shows with amateur hosts (zhenren liaotianxiu 、、、、、). celebrification, which rojek describes as a familiar mode of “cyberself-presentation,” is evident in chinese social media platforms used for “presenting the self,” “prosuming” (simultaneous production and consumption) in the guise of internet parody (egao 、、), publishing fan fiction and constructing online fan communities. some users have gained fame and income from web-advertising and product endorsement deals from “performing” on streaming platforms like meipai (、、) and video-sharing sites like kuaishou (、、). from lifestyle gurus like lingling 、、, gamers like jy daishi jy 、、 to irreverent social commentators like papi jiang (jiang yilei 、、、 ), the popularization of “diy celebrity” platforms allow chinese desiring celebrity to sidestep gatekeepers in the media and entertainment industries. technological affordances and “consumer” demand mean that the possibility of celebrity is no longer restricted to elite performers and graduates of state academies. streaming platforms celebrate the ordinary, giving all manner of subculture enthusiasts, exhibitionists and talented (or not) amateurs the chance to experiment with an accessible celebrity-making apparatus. the streaming business is lucrative, growing and attracts substantial commercial investment. however, the state control apparatus has responded quickly to the potential for video and streaming platforms to become a potentially subversive site for presenting, negotiating and challenging “orthodox” cultural meanings. in may , the moc shut down more than , live streaming hosts citing content they judged to be “vulgar, obscene, violent, superstitious, and damaging to the psychological health of juveniles.” the cac launched strict new rules requiring companies to enforce controls on senft . boorstin , . , – . china internet network information center. . “di ci zhongguo hulianwang fazhan qingkuang tongji baogao” (the th statistical report on internet development in china), january, http://www.cnnic.net.cn/hlwfzyj/hlwxzbg/hlwtjbg/ /p .pdf. accessed june . , – . li ; sima and pugsley . gong and yang . yang . zhang . zhang, liping. . ministry of culture of the people’s republic of china. . “wenhuabu yanguan wangluo biaoyan shichang yancha guanting weigui zhiboping” (ministry of culture to strictly control online performance market and strictly investigate and shut down illegal live-streaming), may, http://www.mcprc.gov.cn/whzx/whyw/ /t _ .html. accessed june . http://www.cnnic.net.cn/hlwfzyj/hlwxzbg/hlwtjbg/ /p .pdf http://www.mcprc.gov.cn/whzx/whyw/ /t _ .html content broadcast on their streaming platforms. in june , saaprt warned that online programming must “advance patriotism, extol the motherland and praise heroes” and not engage in “wasteful star-chasing.” these measures demonstrate that the state believes the informal celebrity sphere requires the same circumscriptive controls as its industrial cousin. internet celebrities may resemble carnival performers, but in a controlled society the carnival is also carefully regulated. conclusion celebrity is frequently overlooked in scholarly work on politics, society and culture in china. furthermore, china is largely absent from the substantial, us- and uk-centric celebrity studies literature. both absences are regrettable given the scale and distinct nature of china’s experience with celebrity in the reform era. chinese celebrities have derived financial, cultural and symbolic capital through a combination of their professional roles, constant publicity and the influence that the crafted celebrity persona exerts on the “experience of everyday life and its implication in the construction and definition of cultural identity.” the state is acutely aware of this “celebrity power,” attributing a range of responsibilities that come with celebrity status and adding specific layers of regulation to individual celebrity conduct to reinforce the multidimensional controls prevailing over the media, internet, advertising, cultural industries and society. harnessing the power of celebrity on the public consciousness to facilitate their goals to govern and seek economic gains, state and industry actors fabricate celebrities as exemplars of model behaviours relating to consumption, “middle class” and “traditional” values, patriotism and acceptance of the political regime. distinguished by multi-layered formal and informal institutions of control and the party’s determination to maintain the “commanding heights” of media and cultural production, chinese celebrity is different to the western societies that dominate the celebrity studies literature. for instance, due to the exigencies of state control and a vastly different political culture, china has resisted the “celebritization of politics” that reached its apotheosis in the us with the election of celebrity businessman and reality tv star donald trump to the american presidency in . however, the chinese celebrity industry is not unique. celebrities in other contexts also serve multiple principles and occupy a liminal space between state, market and publics. patriotism is expected of celebrities in other nations and the training and careful manufacture of performers is common to other asian societies, notably korea. like their democratic counterparts, the communist party has shown a growing appreciation of the utility of the mechanics of contemporary celebrity creation, incorporating lessons from professional pr, marketing and advertising into a nascent hybrid “pop-propaganda” system used to promote some state actors, state-sanctioned role models and “manage the message.” and despite distinct ideological, historical and social factors, not least the tension between the china digital times. . “cyberspace admin issues new live-streaming rules,” november, http://chinadigitaltimes.net/ / /cyberspace-administration-issues-new-live-streaming-rules/. accessed june . south china morning post. . “china’s media watchdog, tightening control of content, promotes ‘core socialist values’,” june, http://www.scmp.com/news/china/policies-politics/article/ /chinas-media- watchdog-tightening-control-content. accessed june . herold and marolt . turner , . zhao , . kim . http://www.scmp.com/news/china/policies-politics/article/ /chinas-media-watchdog-tightening-control-content http://www.scmp.com/news/china/policies-politics/article/ /chinas-media-watchdog-tightening-control-content individualism inherent in the idea of “the star” and china’s collectivist cultural foundations, young chinese demonstrate a thirst for celebrities and have embraced online celebrity-making platforms. in sum, these factors make chinese celebrity a fertile research area for scholars in both the china and celebrity studies fields. bibliographical note jonathan sullivan is director of the china policy institute and associate professor at the school of politics and international relations, university of nottingham. séagh kehoe is a phd candidate at the school of politics and international relations, university of nottingham. 、、: 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http://english.sina.com/entertainment/ / / .html http://www.sixthtone.com/news/ /authorities-aim-to-stem-the-tide-of-immoral-live-streaming http://www.sixthtone.com/news/ /authorities-aim-to-stem-the-tide-of-immoral-live-streaming one-step multiplex transgenesis via sleeping beauty transposition in cattle scientific reports | : | doi: . /srep www.nature.com/scientificreports one-step multiplex transgenesis via sleeping beauty transposition in cattle wiebke garrels , ,*, thirumala r. talluri ,*,†, ronja apfelbaum , yanet p. carratalá , , pablo bosch , kerstin pötzsch , esther grueso , zoltán ivics & wilfried a. kues genetically modified cattle are important for developing new biomedical models and for an improved understanding of the pathophysiology of zoonotic diseases. however, genome editing and genetic engineering based on somatic cell nuclear transfer suffer from a low overall efficiency. here, we established a highly efficient one-step multiplex gene transfer system into the bovine genome. genetically modified cattle are important for developing new biomedical models , , and for an improved under- standing of the pathophysiology of zoonotic diseases, like tuberculosis and bovine spongiform encephalop- athy (bse) , . recently, it was demonstrated that designer nucleases, such as zinc finger nucleases (zfn) and transcription activator-like effector nucleases (talen) are suitable for genome editing in cattle , – . however, genome editing and genetic engineering based on somatic cell nuclear transfer (scnt) suffer from a low over- all efficiency – , due to extensive micromanipulation and nuclear reprogramming failures. the scnt protocol includes sequential micromanipulation steps (enucleation, transfer of donor cell, fusion of cytoblast and donor cell, and activation of reconstructed embryos), which requires highly skilled experimenters, reliable oocyte supply and a large herd of surrogate animals. in addition, animal cloning is associated with increased rates of abortion and health problems, such as the large offspring syndrome, due to incomplete epigenetic reprogramming of the somatic donor nuclei . considering the long gestation ( months) and long generation interval ( – months) in cattle, more efficient methods are required to fully exploit the biotechnological potential and to increase the pace of genetic engineering in this species. here, we established a highly efficient one-step gene transfer system into the bovine genome of in vitro fer- tilized (ivf) zygotes, allowing the simultaneous integration of several independent transgenes delivered by the sleeping beauty (sb) transposon system. results modular mixtures of the transposons and a helper plasmid, encoding the hyperactive sb × transposase were co-injected into the cytoplasm of ivf zygotes (fig. ; table ). upon expression of the sb × transposase, the enzyme catalyzes independent integrations of the transposon constructs into the bovine genome. bovine zygotes were produced from oocytes derived from slaughterhouse ovaries by in vitro maturation and ivf with frozen-thawed sperm according to standard protocols on two experimental days. altogether zygotes were injected with a plasmid mixture of pcvm-sb × , and either two (pt caggs-venus and pt cryaa-tdtomato) or three transposons (pt caggs-venus, pt cryaa-tdtomato and pt casein-e ) at – hours post-fertilization (table ). the pcaggs-venus transposon carried a ubiquitously active promoter (caggs) driving the venus fluoro- phore. the pcryaa-tdtomato transposon carried a lens cell-specific crystallin a alpha promoter driving the tandem (td) tomato fluorophore, and the pcasein-e transposon carried an udder-specific promoter driving a recombinant e glycoprotein of classical swine fever virus. the venus and tdtomato reporter constructs allowed for the vital recording of widespread or cell type-restricted expression (fig. ), respectively. an approximate vol- ume of pl with a dna concentration of ng/μ l and equimolar quantities of the plasmids was injected directly friedrich-loeffler-institut, institut für nutztiergenetik, neustadt, germany. institute for laboratory animal sciences, medical school hannover (mhh), germany. animal biotechnology department, center for genetic engineering and biotechnology, havana, cuba. departamento de biología molecular, fcefqyn, universidad nacional de río cuarto, córdoba, argentina. paul-ehrlich-institute, langen, germany. *these authors contributed equally to this work. †present address: national research centre on equines, bikaner, india. correspondence and requests for materials should be addressed to w.a.k. (email: wilfried.kues@fli.bund.de) received: november accepted: february published: february open mailto:wilfried.kues@fli.bund.de www.nature.com/scientificreports/ scientific reports | : | doi: . /srep figure . one-step generation of multi-transgenic cattle. (a) cytoplasmic injection of transposon plasmids into bovine zygotes. mixtures of the helper plasmid, encoding the hyperactive sb × transposase and either two (pt caggs-venus and pt cryaa-tdtomato) or three transposons (pt caggs-venus, pt cryaa- tdtomato and pt casein-e ) were co-injected into the opaque cytoplasm of a bovine zygote. upon expression of the sb × transposase, the enzyme will catalyze integration of the transposon constructs by a precise cut- and-paste mechanism , . (b) schematic depiction of the used plasmids. pcmv-sb × , expression plasmid of transposase (helper plasmid); and three sb transposon plasmids: pt caggs-venus, ubiquitously active caggs promoter driving venus fluorophore; pt cryaa-tdtomato, lens specific promoter driving tdtomato; pt casein-e , udder-specific promoter driving e subunit of classical swine fever virus. arrows indicate sb inverted terminal repeats. (c) triple transposon transgenic calf shown under excitation of venus and tdtomato. note the widespread venus-fluorescence in snout, hooves and hair; and the lens-specific expression of tdtomato. (d) same animal as in c). inset, imaged under white light conditions. (e) expression of the venus fluorophore in white hair, in black hair the fluorescence is quenched. wildtype controls are shown in fig. s . (f) corresponding control image to e) (white light condition). (g) expression of venus in leukocytes from triple- transgenic calf (tg) and a wildtype control (wt). (h) genotyping of transgenic calves by pcr. m, size marker; , triple transgenic calf; , double-transgenic calf; , wt gdna; , positive control (plasmids, except for polya pcr); , no template control. venus, tdtomato and e pcrs indicate presence of the respective transposon; sb and bb pcrs indicate absence of helper plasmid and transposon backbones; polya, positive control pcr. (i) immunodetection of lens-specific expression of tdtomato (top) and ubiquitous expression of venus (bottom) in organ samples from the double-transgenic calf by western blotting. m, molecular size marker (magic mark); pos., positive control (mcherry and venus); neg., negative control (wildtype muscle sample); , muscle; , liver; , kidney; , heart; , vitreous body; , eye lens; , fat tissue. arrows indicate calculated the molecular weight of tdtomato ( kd) and venus ( kd). www.nature.com/scientificreports/ scientific reports | : | doi: . /srep into the cytoplasm (fig. a,b), without attempting to identify and to inject a pronucleus. this “blind” deposition into the cytoplasm allows a more rapid pace of the injection procedure, and avoids any high-speed centrifuga- tion to reveal the pronuclei in the opaque bovine zygotes. injected (n = ) and control (n = ) zygotes were cultured in synthetic oviduct fluid (sof) in a humidified atmosphere with reduced oxygen ( % o ). after days of culture, the embryos were inspected for development to blastocysts and expression of the venus reporter. the injections on the two experimental days were performed by two different experimenters, respectively, which beside the variable quality of the abattoir ovaries may have contributed to the different developmental rates to blastocysts ( . and . % in the treatment groups). venus-positive blastocysts were selected for embryo trans- fer (et, blastocyst was transferred per recipient) to synchronized surrogate animals. a total of blastocysts at day of in vitro culture with reporter expression of venus were obtained. due to scarcity of recipient animals only blastocysts were used for embryo transfer. in the injection groups, reduced rates of blastocyst formation were found compared to the culture controls, which may indicate that the treatment reduced the regular cleavage divisions. on experimental day two blastocysts, and on experimental day four blastocysts were transferred to synchronized surrogates (n = ), resulting in two pregnancies (table ). both pregnancies run to term, and two normally developed and vital calves, a male and a female were delivered by cesarean section. the female calf was normal sized, was normally breathing and did not show any visible abnormalities, unfor- tunately the initial veterinarian assessment did not detect an aneurism directly at the connection of the umbilical cord to the peritoneum. after – minutes, when the calf attempted to stand up, the aneurism was ruptured, leading rapidly to a hypovolemic shock and death. also, the necropsy did not reveal any macroscopic abnormal- ities, except the aneurism (supplementary material, fig. s ). the male calf (fig. c–g) developed normally and is currently months old. phenotypic analysis suggested that both calves were indeed multi-transgenic, showing widespread expression of venus and lens-specific expression of tdtomato (fig. , supplemental fig. s ), this was confirmed by immunoblotting of samples from the deceased female calf (fig. i). genotyping and molecular anal- yses confirmed the integration of both reporter transposons in the female calf (table ; supplemental table s ). the male calf was confirmed to be triple-transgenic, carrying all three transposons. the identification of flanking genomic sequences by splinkerette pcr identified individual sb transposase-catalyzed integrations in consensus ta-dinucleotide sequences (supplemental table s ), on chromosomes , , , , within a repetitive element, and two positions, which could not be annotated in the bovine genome due too short flanking sequences. the absence of helper plasmid and transposon backbone sequences in the genomes of the transgenic calves was con- firmed by pcr (fig. h). deposition of the ubiquitously expressed venus in the hair was detected (fig. e,f; supplementary fig. s ). flow cytometric analysis of primary fibroblasts derived from the female calf showed that % of the cells were venus positive, whereas % of fibroblasts and – % of leukocytes from the male calf were venus positive, suggesting that the founders showed some cellular mosaicism, which may be due to integration after the one-cell stage (supplementary fig. s –s ). discussion the here established cytoplasmic injection of zygotes with sb transposon plasmids is both technically simple and highly efficient for multiplex transgenesis in cattle. pre-selection of venus-positive bovine blastocysts for embryo transfer after one week of in vitro culture likely contributed to the % rate of multi-transgenic calves per born calves. the sb catalyzed gene transfer resulted in precise transposition of the reporter cassettes flanked by the itrs of the sb transposon. this is the first description of multi-transgenic cattle generated by a microinjection technique, allowing for the generation of complex transgenic genotypes in the cattle model within a reasonable time frame. in the first experiments striving to generate transgenic cattle by standard pronuclear microinjection, the experimenters typically injected thousands of zygotes – and performed dozens of embryos transfers, resulting at best in about % transgenic calves per born animals. even worse, only a sub-fraction of the transgenic cattle showed expression of the transgene, thus further reducing the ratio of “useful” transgenic offspring. here, we obtained two multi-transgenic calves out of two born calves from a limited number of injected zygotes (n = ). the main factors reducing the efficiency of the here described transgenic approach are the current methods for in vitro culture for bovine embryos and embryo transfer of ivf-derived blastocysts to synchronized surrogate animals. standard (commercial) ivf systems commonly achieve blastocyst rates of no more than % of the fertilized zygotes, and embryo transfer of ivf-derived blastocysts typically result in pregnancy rates of no more than % after a single embryo transfer. considering these general limitations and the availability of experi- mental day treatment no of zygotes injection mixture no of blastocysts, day (%) no of venus- positive blastocysts no of ets no of pregnancies (day ) no of calves no of transgenic calves (% of et/ % of born) sex/birth weight cpi pcmv-sb × , pt caggs-venus, pt cryaa-tdtomato. ( . ) , double transgenic ( / ) female/ kg culture control n.a. ( . ) n.a. n.a. n.a. n.a. cpi pcmv-sb × , pt caggs-venus, pt cryaa-tdtomato, pt casein-e . ( . ) , triple transgenic ( / ) male/ kg culture control n.a. ( . ) n.a. n.a. n.a. n.a. table . one-step multiplex transgenesis in cattle. n.a., not applicable. www.nature.com/scientificreports/ scientific reports | : | doi: . /srep only surrogate animals, the overall success rate of two multi-transgenic calves out of treated ivf zygotes compares rather favorable to previous approaches. this approach expands the toolbox of genome engineering technologies in cattle, it is likely that experiments striving for co-expression, conditional expression or gene knock-down in cattle will benefit from the strategy described here. a further advantage of the transposition-based gene delivery strategy is that no unwanted dna sequences, such as antibiotic markers or plasmid backbones, will be introduced into the genome . importantly, the transposon-based approach is simple, efficient and allows the modular design of genetic modifications. both calves showed some cellular mosaicism for the venus transposon driven by the ubiquitously active caggs promoter, resulting in – % venus-negative cells. the venus-negative cells did not carry the reporter transposon, as determined by flow cytometric sorting and pcr amplification (fig. s ). the cellular mosaicism may be due to transposition after the one-cell stage, or alternatively due to re-mobilization of an early integra- tion event without a secondary integration in some blastomeres, depending on the half-life and distribution of the transposase enzyme. previous own experiments with sleeping beauty transposition in murine and porcine zygotes, however, suggest that this low level of cellular mosaicism in the founders is not critically for germline transmission of the introduced dna transposons , . the one-step in ovo transposition might be of particular interest for genetic approaches, where two or more transgenes need to be inserted into the bovine genome. it has been shown that the expression of recombinant proteins in the udder can be enhanced by co-expression of enzymes for posttranslational modification . the co-expression of recombinant proteins, which have synergistic effects , or different subunits, which assemble to functional protein complexes , would be simplified by this method. the stable integration of binary cassettes of inducible systems or designer nuclease components, which may confer disease resistance, are other possible application scenarios . material and methods ethics statement. animals were maintained and handled according to the german laws regulating animal welfare, and genetically modified organisms. the experiments were approved by an external ethics committee (niedersächsisches landesamt für verbraucherschutz und lebensmittelsicherheit, az . - - - / ). production of bovine in vitro zygotes. ovaries were collected from a commercial slaughterhouse, and cumulus-oocyte-complexes (coc) were released by slicing with a blade. the coc were matured in tcm medium for hours, cocs with expanded cumulus layer were then fertilized in vitro, and presumptive fertilized oocytes were placed in tcmair medium . sleeping beauty transposon system plasmids. the pcmv- x and pt caggs-venus plasmids were described before . for the pt cryaa-tdtomato transposon, the cryaa promoter-tdtomato gifted by dr. xu (yale) was subcloned between the sb itrs. in the pt casein-e transposon, a bovine/buffalo casein promoter-e subunit cdna of classical swine fever was subcloned between the sb itrs. the plasmids were ampli- fied in xl or dh alpha e. coli strains and purified by commercial anion exchange columns (qiagen tip ). cytoplasmic injection of transposon plasmids. the transgenic calves were generated by cytoplasmic plasmid injection of sb plasmid mixtures into bovine ivf zygotes essentially as described previously for porcine zygotes , . in brief, equimolar mixtures of the plasmids with a total dna concentration of ng/μ l in injection buffer ( mm trishcl ph . / . mm edta) were prepared directly before injection. the injection solution was backfilled in injection capillaries with a filament. injection and holding capillaries were arranged on micro- manipulators on a micromanipulation unit with an inverted microscope . small groups of – ivf zygotes were transferred into a drop of medium ( μ l) on a glass plate. unlike for pronuclear injection, here no high speed centrifugation with ~ g is required. the non-centrifuged zygotes appear opaque, and shall bear two polar bodies, however the pronuclei were not discernable. individual zygotes were fixed on the holding capillary by gentle suction, and then the zona pellucida and the cell membrane were penetrated with the injection capillary. approximatly picoliter (pl) of the plasmid injec- tion was deposited inside the cytoplasm. in vitro culture of injected embryos. treated zygotes were then put in a μ l drop of synthetic oviduct fluid (sof) covered with mineral oil and incubated at °c in an atmosphere with reduced oxygen ( %) for days. then the number of developed blastocysts was determined, and the expression of venus was checked under a microscope with epifluorescence. embryo transfer and determination of pregnancy. venus-positive blastocysts were individually loaded in embryo transfer straws (minitube minipalilette . ml) in - μ l of pbs. non-surgical et was per- formed on hormonally synchronized surrogate animals. the establishment of a pregnancy was tested by palpation and ultrasound analysis days later. fluorescence microscopy and macroscopic fluorescence excitation of animals. for fluorescence microscopy of cell cultures, a zeiss axiovert m microscope equipped with fluorescence optics was used. for specific excitation of venus a filter block with excitation of – nm and emission of – nm, for specific excitation of tdtomato a filter block with excitation of – nm and emission of – nm were used. for imaging of tissue biopsies an olympus sz stereomicroscope with epifluorescence optics was used. for macroscopic imaging of the calves, either blue or green flood lights of light emitting diodes (led; eurolite) were used for excitation, and images were recorded with a digital camera and appropriate emission filters (lee filter) . www.nature.com/scientificreports/ scientific reports | : | doi: . /srep genotyping and identification of integration sites. transposon-genomic dna junctions were determined using splinkerette pcr as described . the purified pcr product was cloned into the pgem-teasy vector (promega, madison, usa), and the dna sequence was determined by standard sequencing technology (abi xl applied biosystems, foster city, california). sequences were analyzed with blast (www.ensembl. org). southern blots and pcr reactions of genomic dna were done according to standard procedures , . preparation of primary cell cultures and facs measurements. primary cells were derived from tissue samples of newborn calves as described and cultured in dmem supplemented with % fetal calf serum, mm l-glutamine and antibiotics. leukocytes were isolated from edta-blood samples and re-suspended in pbs. flow cytometry analysis of primary cells and leukocytes was performed using a facscan (bd bioscience, heidelberg, germany). samples were diluted to . × cells/ml and measured in duplicates, acquiring cells per sample. cells with membrane damage were excluded from the analysis by counterstaining with propid- ium iodide ( μ m). western blotting. finely grinded tissues and cells were extracted in ripa buffer, and microgram of pro- tein per slot was separated on a % sds-page gel, blotted to a pvdf membrane, blocked in % non-fat milk powder and probed with rabbit polyclonal antibodies against egfp (thermo) or mcherry (santa cruz) in : dilutions, respectively, followed by a secondary anti-rabbit antibody in : dilution (sigma-aldrich). the anti-mcherry antibody cross-reacts with other red fluorescent proteins, and is suitable for the detection of tdto- mato (calculated molecular weight kd). for chemiluminescence detection an ecl + kit 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and iv / - ), the daad-conicet (wak and pb), the icar (international fellowship to trt) and the boehringer ingelheim fundation (ypc). the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. http://www.ensembl.org http://www.ensembl.org www.nature.com/scientificreports/ scientific reports | : | doi: . /srep author contributions w.g., z.i. and w.a.k. wrote the main manuscript text. w.g., t.r.t., r.a., y.p.c., p.b., k.p. and e.g. performed the experiments and analysed the data. all authors reviewed the manuscript. additional information supplementary information accompanies this paper at http://www.nature.com/srep competing financial interests: the authors declare no competing financial interests. how to cite this article: garrels, w. et al. one-step multiplex transgenesis via sleeping beauty transposition in cattle. sci. rep. , ; doi: . /srep ( ). this work is licensed under a creative commons attribution . international license. the images or other third party material in this article are included in the article’s creative commons license, unless indicated otherwise in the credit line; if the material is not included under the creative commons license, users will need to obtain permission from the license holder to reproduce the material. to view a copy of this license, visit http://creativecommons.org/licenses/by/ . / http://www.nature.com/srep http://creativecommons.org/licenses/by/ . / one-step multiplex transgenesis via sleeping beauty transposition in cattle introduction results discussion material and methods ethics statement production of bovine in vitro zygotes sleeping beauty transposon system plasmids cytoplasmic injection of transposon plasmids in vitro culture of injected embryos embryo transfer and determination of pregnancy fluorescence microscopy and macroscopic fluorescence excitation of animals genotyping and identification of integration sites preparation of primary cell cultures and facs measurements western blotting additional information acknowledgements references application/pdf one-step multiplex transgenesis via sleeping beauty transposition in cattle srep , ( ). doi: . /srep wiebke garrels thirumala r. talluri ronja apfelbaum yanet p. carratalá pablo bosch kerstin pötzsch esther grueso zoltán ivics wilfried a. kues doi: . /srep nature publishing group © nature publishing group © macmillan publishers limited . /srep - 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(print)/issn - (online)/ / – © taylor & francis doi: . / sustainable development education in scottish schools: the sleeping beauty syndrome marie jeanne mcnaughton* university of strathclyde, uk taylor and francisceer_a_ .sgm . / environmental education research - (print)/ - (online)original article taylor & francis november mariejeanne mcnaughtonm.j.mcnaughton@strath.ac.uk this paper reviews and discusses the development of sustainable development education (sde) policy within the context of the scottish formal school system. the focus is on the progress, and lack thereof, of implementation of sde in schools in the light of some of the key curriculum docu- ments and associated political decisions and advisory reports. the period of the review dates from , which saw the publication of a report that was regarded as the seminal document for the development of environmental education in scotland, to and the scottish executive’s propos- als for sde in the light of curriculum reform for schools for the st century. the paper employs, loosely, the metaphor of the sleeping beauty to tell the story of sde in scotland in three parts: the story’s three phases of emergence, obscurity and re-emergence might serve as a useful metaphor, here. introduction this paper discusses the development of sustainable development education policy in the context of the scottish formal school system. while lavery and smyth ( ) reviewed and analysed environmental education in scotland from international and political perspectives, the focus here is on the implementation of sustainable develop- ment education in the scottish school system in the light of key curriculum documents and associated political decisions and advisory reports. the period of the review dates from learning for life (soend, ), regarded by many as a seminal document for the development of environmental education in scotland, to the years beyond a curriculum for excellence (secrg, ), the scottish executive’s document setting out a proposal for curriculum reform for schools for the twenty-first century. * department of childhood and primary studies, university of strathclyde, jordanhill campus, glasgow g pp, uk. d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton the sleeping beauty: a metaphor when describing and analysing the story of environmental education and sustain- able development education in australia, gough (as discussed in greenall, ; chapman, ) uses the analogy of a game of snakes and ladders to describe the uneven progress of political and educational policies and practice. this paper loosely employs the metaphor of the sleeping beauty to tell a three-part story of sustainable development education in scotland: ● in part , the rio earth summit in is identified as a catalyst for the development of the scottish environmental education document, learning for life ( ). (the birth of the princess, beauty, was considered to herald a time of hope for the land.) ● part describes and discusses how a number of obstacles obstructed the progress of sustainable development education in schools. (circumstances conspired against the princess and she and all of the court fell into a long sleep. a large forest grew around the castle and it became lost from sight and mind.) ● in part , the proposal document for a new scottish curriculum, a curriculum for excellence ( ), and the emergence of an action plan for sustainable development in scotland, may be viewed as the beginning of a more promising future for sustainable development education. (a champion emerged, a way was found through the forest and the princess awoke…) while there is no intention to become bogged down in analogy, the story’s three phases of emergence, obscurity and re-emergence are used to organize and develop this commentary on sustainable development education in scottish schools. the approach in this paper also draws on systematic review procedures in the tradition of curriculum history research by, for example, hamilton ( ), krindel and newman ( ), and the curriculum literature review published in the scottish executive social research ( ) document, sustainable development: a review of international literature. techniques and strategies include: setting clear review objec- tives; conducting a wide literature search using library resources, academic search engines and searches of appropriate sustainable development education-related and government web sites; and mapping of common educational themes, as well as noting any inconsistencies. the literature review has focused on the key areas of sustainable development education in the formal education sector in scotland, political responses to proposals designed to raise the status of sustainable development education and, more gener- ally, the topic of curriculum reform and development. initially, the scope of the search was national, although this has widened to include an international dimension as common themes emerged. given the context for the study, the review’s baseline has been the recommenda- tions and strategies proposed in learning for life (soend, ). in what follows, i start by analysing how key generic educational themes emerging from that document fit with educational philosophies underpinning or allied to sustainable development education. i argue that these themes illustrate sound pedagogy and ‘excellence’ in d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools education and are mirrored in current literature related to sustainable development education, both in the scottish context, and from international perspectives. while the paper aims to examine general themes and principles underpinning curriculum development in sustainable development education in scotland, it does not, however, track the progress of sustainable development education in terms of specific examples from scottish schools practice or from teachers’ experiences. these remain key areas for further investigation in subsequent studies. part : learning for life and the emerging pedagogies of sustainable development education in scotland this section sets out a context for understanding the development of sustainable development education in scotland. it suggests that a close analysis of the key sustainable development education document, learning for life (soend, ), reveals key pedagogical themes indicative of what have been regarded as sound prin- ciples for curriculum development in this field. educational policy and debate in scotland has a long history of interest in the links between education and environment. this is demonstrated in, for example, the hmi ( ) report, environmental education (produced by the national government inspectorate of education), and, curriculum guidelines for environmental education (seec, ) (produced by the national environmental education advisory council). learning for life (soend, ) was produced by the working group in environ- mental education for the secretary of state for scotland. a prompt and comprehen- sive response to the united nations conference on environment and development (unced) earth summit in rio de janeiro in and in particular, chapter , agenda , the report demonstrated scotland’s then apparent commitment to progressing the development of environmental education. learning for life detailed a set of recommendations such that their implementation would commit scotland to developing policies that would encourage more sustainable lifestyles—locally, nation- ally and globally. central to this were recommendations for education policy with a strong focus on teaching and learning that might ‘alert everyone to the importance of the environment in daily life and also to its vulnerability’ (p. ). learners developing environmental awareness, literacy, responsibility, and competence, it was argued, could achieve this. learning for life also set out a four-phase model of environmental and sustainability education in schools: reactive, receptive, constructive and pro-active (hesselink, , in learning for life, p. ). in the first phase, schools are characterized as relying on externally generated, pre-written materials and enthusiastic individuals, while by the fourth phase, the whole culture of the school is defined in terms of sustainable living, supported by neighbourhood enterprises, such that pupils and staff are both empow- ered to take initiatives and able to make active, participative responses in local, national and global issues. learning for life estimated that, in , most scottish schools were at the first or second phase with ‘one or two adventurous projects’ typifying the third or fourth. d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton hope was expressed that in the following decade, more would be achieved and that schools would be helped and encouraged to move to phases and models of environ- mental education which would lead both pupils and teachers to deeper understand- ing, higher levels of critical thinking, and, ultimately, to making choices that lead to more sustainable ways of living. key educational themes in learning for life borradaile ( , p. ) observes that learning for life ‘still provides a wealth of ideas and aspirations to be drawn upon, many of the recommendations are as relevant today as a decade ago’. although the focus of learning for life was environmental and sustainability education, it can also be viewed as being based upon and promoting a model of sound generic educational practice, applicable to many contexts and educa- tion systems. its view of ‘good sustainable development education’, as i show below, was grounded in and is reflective of contemporary understandings of effective peda- gogy in education and the field. an analysis of learning for life in relation to the formal education, suggests six key educational themes. these themes are that environmental and sustainability education should be: systemic, holistic, active and participative, based on and in the environment, values focused, and should enable learners to be competent to take action for the environment. together, these might be viewed as learning for life articulating a model for progressive, transformative education focused on environment and sustainability. systemic learning for life recognizes that if its suggestions for the development of environmental and sustainability education were to be implemented successfully, then the whole system, that is, government and its agencies, commercial and voluntary sectors, education bodies and schools, must work in partnership. this corresponds well with sterling’s ( ) vision of sustainable education, which explores the implications of an ecological paradigm for education. sterling applies three contextual levels to whole-systems thinking about education: the educational paradigm, which reorientates thinking about the purposes of education and asks how this relates to society and the biosphere; organization and management of learning environments, which investigates how the whole management system views policies and practice towards education and the environment; and learning and pedagogy, which questions whether and how practices are redesigned to put into practice a participative, integrative model of learning and teaching. holistic learning for life envisions a model of the curriculum in which learning in environmen- tal and sustainability education are an integral part of the learning and teaching programmes of all schools: the approach permeates the whole curriculum. indeed, d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools brady and brady ( ) aver that not giving pupils a framework for linking knowl- edge, ideas, skills and values about the environment is the major failure of modern education. in contrast, it is argued, an integrated curriculum crosses the boundaries imposed by traditional subject groupings and allows students to move across disci- plines as they learn about their world. however, an integrated curriculum does not deny the distinction between those subjects or learning areas, as learning for life acknowledges: they remain important for the purposes of balance and organization of specific subject knowledge. active and participative learning for life suggests a model of sustainable development education wherein the emphasis of the teaching and learning strategies encompasses a wide range of active, participative experiences, including pupils engaging in investigative, discursive, and open-ended tasks. contexts focus on local perspectives and build towards global environmental issues, with emphasis on both knowledge and values. this view of learning is not by any means exclusive to learning for life or sustainable development education. selley ( ) suggests that learners must be allowed to construct their knowledge and understanding through active and local participation where they have the opportunity to discover facts, ideas and meanings. similarly, säljö’s ( ) phenomenographic studies of students’ conceptions of learning contrast categories such as passive, rote knowledge acquisition and memorizing, with the ability and opportunity to use facts to make sense of their worlds and to comprehend, reinterpret and actively construct knowledge and ideas. based on and in the environment education outside of the classroom, i.e., in the environment, is identified as a basic principle in learning for life. regular direct experience in the school grounds, the local areas and outdoor programmes further afield are all identified as rich resources for developing observation skills and for learning about, caring for, and interacting with the environment, thus providing enjoyable and effective learning. liaison with envi- ronmental education agencies provides support and inspiration. the – environ- mental studies (soed, ) document also advises that first-hand experience though fieldwork for pupils is central to the methodology of environmental studies. values-focused powney et al. ( , p. vii) state that, ‘values include but go beyond the religious and moral areas of belief: “values” refers also to other aspects of how our lives are sustained, organized and experienced’. at the heart of sustainable living must be a set of values, held by individuals and by society, by which they try to live and make choices. in learning for life, the school ethos and values system—the hidden curricu- lum—is viewed as having an important influence on the effectiveness of environmental d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton education in both local and global issues. the ethic for sustainable living, central to caring for the earth (iucn, ) is also viewed as fundamental in learning for life: care and respect for the community of life. ethical dilemmas, for example, the right to meet human needs and wants versus the importance of preserving natural resources, can and should be addressed through education at all levels and over a range of subjects. competent to take action finally, and perhaps most importantly, learning for life asserts that environmental education should enable learners to be competent to take action and that the success of any educational strategy should be judged against its effect on the capacity and will- ingness of people to take action for the environment. a recurring theme throughout learning for life is that each school produce an environmental action plan that helps pupils to be active participants in the care and stewardship of the local and global aspects of the world in which they live. laing and mcnaughton ( ) propose a similar model of environmental action competence (after jensen, ) wherein educa- tors are offered strategies to enable pupils to have knowledge and insight about sustainability issues, vision and commitment to the issues and, ultimately, can take action in regards to the issues. summary the emergence of learning for life, then, provided a clear, forward thinking and peda- gogically appropriate curriculum proposal for the field in the s, which might have placed scotland’s formal education sector at the forefront of the environmental and sustainability education response to agenda , alongside countries such as the netherlands (teaching for sustainable development, – , cited in sdelg, ) and new zealand (guidelines for environmental education in new zealand schools, published in from a pilot study begun in ), and ahead of the other countries of the uk (see reid et al., , for a review). the next section sets out a brief outline of the progress, and lack thereof, in terms of developments in curriculum policy in sustainable development education for the years between and the publication of a curriculum for excellence (secrg, ). this scottish example serves to remind us of the problems inherent in implementing fundamental, systemic curricular change in the absence of clear political will or educational consensus. the metaphorical touchstone here is of the ideas emerging from learning for life becoming ‘lost in the forest’. part : sustainable development education policy and practice— years in the forest a main aim of learning for life was to ‘ensure that a national strategy for environmen- tal education is both practical and attractive’ (soend, , p. ). however, in the d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools years after , there seemed to be little general enthusiasm for the adoption of sustainable development education as a process or as a focus area in curriculum plan- ning. the prevailing view was that sustainable development was a ‘fringe’ issue with little real status or relevance to education (borradaile, ). this perspective coin- cides with the introduction of the national curriculum in england in with its increasing emphasis on exam results league tables and a political rhetoric focused on raising standards and back to basics: arguably a conservative and neoliberal response to the more ‘progressive’ education policies of the s. lavery and smith ( ) consider the fact that a policy for sustainable development education was not put into effect in scotland to be a deliberate political act linked to the refocusing of uk educational priorities in favour of basic skills. tightened, subject-based timetabling with a focus on raising attainment in literacy and numeracy resulted in fewer cross-curricular opportunities and less emphasis on the usefulness of meaningful learning contexts afforded by, for example, sustainable development education, in allowing learners to practice and extend a range of skills in other contexts. this undoubtedly ran counter to the philosophy underpinning the scottish – curriculum (see soed, ). although grouped by subject, the – curriculum guidelines ( – ) were designed to be open-ended and flexible with a great deal of choice to be afforded to schools in terms of curriculum content, and methodology. however, in practice, time, assessment constraints, and an increas- ingly crowded curriculum led to a more top-down, imposed structure than had been anticipated by the architects of the system (bryce & humes, ). in the late s, three important documents pertaining to sustainable develop- ment education were published. the first, learning to sustain (seec, ), raised the concern that the term ‘environmental education’ might be perceived as being concerned only with ‘green’ issues and suggested a change of focus toward ‘sustain- ability education’. the documents, scotland the sustainable and scotland the sustain- able? the learning process (esgd, ), set out a -point action plan which advised that the government should ‘put sustainable development at the heart of education, and education at the heart of sustainable development’ (p. ). central to the action plan was the concept that sustainable development should integrate education and that education needs to be holistic and lifelong with cross-disciplinary approaches— joined up learning, leading to the development of skills in critical analysis—joined-up thinking. however, borradaile ( ) explains, a number of political circumstances, including perceived conflicting interests between government departments and tensions leading up to the establishment of the new devolved parliament for scotland, led to the report being sidelined and the recommendations never being acted upon. in short, from to , a number of circumstances conspired to prevent many of the ideas and strategies from learning for life being adopted in anything more than a piecemeal fashion in the formal education sector. there were many examples of groups and individuals working towards the fulfilment of the sustainable development education objectives. however, there was no overarching policy in place and no general consensus on the status or value of sustainable development education in scottish schools. d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton in these circumstances, curriculum reform is unlikely. chapman ( ) highlights a similar situation when discussing the development of environmental education in australia in the s. he states that, ‘despite the development of a comprehensive environmental plan … little attention was given to the political ramifications of the suggestions and the unpreparedness of teachers in schools’ (p. ). it was a similar lack of direction that accompanied sustainable development education into the new scottish parliament. post- —a new parliament: a new direction? based in edinburgh, july saw the establishment of a devolved parliament for scotland. its legislative competence extends to education, health, agriculture and justice, while other areas, such as foreign policy, are reserved for the parliament of the uk (based at westminster). for fiscal and administrative purposes, prior to the establishment of the new parliament a number of advisory groups in many key public policy areas were wound up. of note for this paper are the early withdrawal of fund- ing from and the subsequent dissolution of the scottish environmental education council (seec), whose membership brought together a wealth of knowledge and expertise in a wide range of local and international environmental education contexts. the break up of the group deprived environmental and sustainability education of a powerful, united voice in the subsequent discussions on educational reform in scotland. a parallel might be drawn here to the publication in australia of learning to care for the environment: victoria’s environmental education strategy in followed by the disbanding of the victorian environmental education council (veec) in , as described in gough ( ). the desire expressed by the new scottish government was to put a review of education in place that would lead to the development of a curriculum fit to meet the needs of the twenty-first century. in , a parliamentary order listing five national priorities for education (scottish executive, ) was published. the fourth of these priorities, values and citizenship, made some loose links with sustainable develop- ment education. here, a key indicator of success identified by the hm inspectorate was the involvement of schools in the eco-schools programme and the achievement of an eco-schools award (eco-schools, ). the eco-schools scheme aims to help schools to move from simple class and school activities using ideas from structured packs and lesson plans through stages towards a whole school ethos of sustainable living, a model which may be likened to that described by hesselink in learning for life. a more critical view might be that the nature of the scheme must remain essentially top-down, with general, external stan- dards and measures being applied to school communities. pupils might be expected to display ‘good environmental behaviour’ without being encouraged to interrogate the underlying issues and values. basic eco-schools awards can be achieved by the self-assessed adoption of short-term environmental projects. therefore, while useful, it may be seen to be rather narrow in terms sustainability education, especially for the secondary school sector (pirrie et al., ). comparisons may be drawn with the d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools more robust european ‘environment and schools initiatives’ (ensi), described by rauch ( ). here, the focus is on a holistic, sustained environmental approach, with an emphasis on pupils being ‘empowered to make active and constructive contri- butions to sustainable development’ (p. ). the publication education for citizenship in scotland: a paper for discussion and devel- opment (lts, ), effectively subsumed sustainable development education within the citizenship agenda. it is notable that no environmental organizations were repre- sented on the advisory citizenship review group. this reflects lavery and smith’s ( ) observation that, from the mid s, ‘the most powerful interpretation of sustainable development at this time was stated in socio-economic rather than eco- physical terms’ (p. ). the document does state that citizenship, is ‘rooted in, and expressive of, a respectful and caring disposition in relation to people, human society in general, the natural world and the environment’ (p. ), and advises that scotland’s pupils were to be helped to become ‘global citizens’. in a review of sustainable devel- opment education post , birley ( ) argued that government progress on educational issues remained fragmentary and concluded that government commit- ment remained hesitant (similar patterns in england post-rio ( ) are identified in reid et al., ; eac, , ). also saw the scottish executive education department (seed, ) publish educating for excellence: choice and opportunity, about which borradaile ( , p. ) notes, ‘specific reference to sustainable development education and the wider outdoor learning environment is absent, despite submissions from wwf and education scotland’. the first years of the new parliament, then, did not appear to herald a great deal of renewed interest in the development of sustainable development education. the view of the inspectorate and local education authorities seemed to be that eco-schools ‘had it covered’. the next section outlines how since , the status of sustainable development education has been raised within the scottish education system: ‘the sleeping beauty awakes’. it discusses the possible implications for sustainable devel- opment education in a curriculum for excellence, in terms of the key pedagogical themes outlined in part . it also examines the progress of sustainable development education in the light of a speech to the ‘learning to make scotland sustainable’ semi- nar (june ) by peter peacock, minister of education and young people, which states that an aim of the new curriculum is to ‘embed sustainable development within the school curriculum as part of our major education reform programme”’(para. ). part : a curriculum for excellence—the sleeper awakens in , the curriculum review group for the scottish office published a curriculum for excellence (secrg, ). this short document outlines a major curriculum reform, expressing a vision for a single scottish curriculum spanning the age range - to -years, that will enable all children to develop four capacities, to become: success- ful learners, confident individuals, responsible citizens and effective contributors to society. a more holistic, experiential and egalitarian cross-curricular approach is emphasized in the introduction and in statements such as, ‘children’s learning should combine to d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton form a coherent experience’ (p. ). importance is placed on making links across the curriculum, of seeing connections, and of dealing with genuine concerns about the world. pupils, it states, should have knowledge and understanding about: the world and scotland’s place in it; different beliefs and cultures; and environmental, scientific and technological issues. this should enable them to develop informed and ethical views and thus to develop values, in terms of respect for others and commitment to participation in society and thus, implicitly, to environmental sustainability. sustainable development education post- coinciding with the curriculum review in a curriculum for excellence and, perhaps, as a reaction to increasing uk-wide and international developments, sustainable devel- opment education has appeared to move further up the agenda, both politically and educationally. the research report, sustainable development education in england, wales, northern ireland and scotland (sdeld, ), confirmed that, compared to other areas of the uk, scotland has not been particularly successful in developing environmental and sustainability education since the s. the publication of unfavourable national comparisons can be a catalyst for government action and this seems to have been the case in the area of sustainable development education. thus, the documentation relating to the progress of a curriculum for excellence curriculum development states that: … it is envisaged that the profile of sustainable development education will be enhanced in accordance with the minister of education’s aspirations, and that it will feature within a curriculum for excellence and be given more prominence within subjects and throughout most cross-curricular-themes. (lts-acfe, ) this indeed seems to be the case and sustainable development education is included in some of the proposed curriculum outlines (lts-acfe, ). the raised status of sustainable development is evident in the publication of choosing our future: scotland’s sustainable development strategy (scottish executive, ), a wide- ranging document covering aspects such as: waste, transport, health and well-being, social justice, and scotland’s natural heritage and resources. the document sought to establish scotland’s international credentials in terms of commitment to sustainable development policy and practice. a follow-on publication, learning for our future: scotland’s first action plan for the un decade of education for sustainable development (sdelg, ) emphasizes the government’s commitment to sustainable develop- ment education, asserting that it can help teachers ‘to deliver the objectives of the new curriculum’ (p. ) within a whole-school approach. a curriculum for excellence and six themes revisited earlier in this paper, six educational themes emerging from learning for life were set out. it was proposed that these themes suggested that learning for life, and by exten- sion sustainable development education, were underpinned by sound pedagogical d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools ideals, corresponding to what sterling ( ) describes as an ‘ecological paradigm’ for education (p. ). many of the same themes appear to underpin the vision state- ments in a curriculum for excellence. however, as with all visions, the realization may be somewhat different. here, the six themes are revisited and discussed in terms of the potential for sustainable development education in the new curriculum, alongside some of the barriers that might militate against this. systemic the scottish executive has made a considerable investment in the development of policies on sustainable development across all areas of government and has expressed a desire that scotland be seen as a country in the forefront of sustainable practice. in terms of education, from , the scottish curriculum body, learning and teaching scotland (lts), has produced documents, statements and web-based information on sustainable development education, signifying an increase in the status of sustainable development education in the curriculum. however, learning for our future ( ) identifies a need for training and awareness-raising in order that policy-makers, especially at local level (for example, local authorities and schools), have the skills, knowledge and understanding to deliver and support sustainable development education. this view is iterated in an extensive piece of international research commissioned by the scottish executive (sesr, ) which found that in terms of delivery of sustainable development (including education) there were, ‘mani- fest gaps in the knowledge base’, ‘inconsistencies in delivery pathways’ and ‘policies in place but no action is taken’ (p. ) in some or all of the national and international practices addressed in the review. holistic the integrated, holistic nature of learning is a recurrent theme in recent documents. a curriculum for excellence states that successful learners should be able to make links and to apply different kinds of learning in new situations that may span several disci- plines. one of the key targets for improvement in the curriculum review, identified in learning for our future (p. ) is: … the coherence between cross-cutting elements such as education for citizenship, envi- ronmental education, outdoor education, international education and education for the global perspective and to integrate them as fully as possible with learning in curricular areas and subjects. however, since the s, some local authorities—the arbiters of the curriculum in scotland—have adopted a rather rigid, product/outcomes oriented view of the curric- ulum, the antithesis of a holistic, cross-curricular approach, and derided in learning to sustain (seec, ) as the ‘product of tidy administrative minds’ (p. ). borradaile ( ) claims that there is often a general lack of understanding of process-based learning, and an over-emphasis on subject based-teaching. a curriculum for excellence d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton advises the use of a more topic-based, cross-curricular approach, especially in primary and the lower secondary years. many teachers, it suggests, may need considerable help to gain (or rediscover) the knowledge, skills and confidence to teach in this way. active and participative a key emphasis of a curriculum for excellence is the provision of active, participative learning experiences. the four capacities described therein, successful learners, confi- dent individuals, responsible citizens and effective contributors, are predicated on the education system including young people in decision-making. schools are encour- aged to develop an open, participatory ethos. learning for our future recognized the scope of sustainable development education to provide a wide range of contexts for active engagement with ideas, for example, in exploring concepts, asking questions, investigating options and suggesting alternatives. however, this does not fit easily with the mental template for ‘education’ held by many non-specialists: the traditional dissemination model of teaching and assessment. politicians and policy makers, with an eye on votes and, in particular, ‘accountability’, often do not wish to commit to anything which might be viewed as radical or different. chapman ( ) identifies lack of political backing as a major cause of the failure of sustainable development education initiatives in australia. in scotland, too, there has been a mismatch between a curriculum viewed in terms of a set of discrete subjects, and sustainable development education, described as a ‘permeator’. on the one hand, there are tradi- tional ‘hard’ attainment targets, goals and improvements to be met. on the other, there is the ‘soft’ curriculum that does not fit easily into a plan–teach–assess–report model and yet may be seen as a more accurate model of the ‘real world’—messy, connected, wide-focused and values driven. based on and in the environment learning for our future makes specific mention of outdoor education stating that it must be considered a valuable part of a rounded and rich educational experience and that schools should develop a whole-school approach. there is an emphasis on the use of the immediate local environment including the school grounds, as well as on visits further afield. taking learning outdoors (white, ) describes the introduction, in , of a two-year outdoor connections programme. it is designed to link current and emerging outdoor education strategies to a curriculum for excellence and to help educators to recognize the benefits (identified in research studies world- wide) of learning in the outdoors. the renewed emphasis on outdoor education is confirmed by the appointment by lts of an outdoor education development officer. however, two main barriers stand in the way of widespread uptake of oppor- tunities for outdoor education: costs, and fear of litigation. robert brown, deputy minister for education and young people, has sought to allay financial concerns by advocating a mixed model whereby most outdoor education would take place within a school’s local environs. he has also commended a government publication health d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools and safety on educational excursions (scottish executive, ), as a means by which teacher confidence might be increased. values-focused in a curriculum for excellence, the government and educational providers are charged with delivering an education system that helps young people to develop a range of positive values about themselves as learners and as future citizens. however, gillies ( ) notes that the prime value on which the new curriculum is to be based—‘excellence’—is never referred to in the document and suggests that this is symptomatic of ‘a certain imprecision over values in the report’ (p. ). he suggests that the curriculum review group’s failure to open up the initial report to pubic consultation resulted in a loss of opportunities to analyse and define the underlying educational values that would fit the recipients of the new curriculum for the challenges of the twenty-first century. this lack of precision does not bode well for sustainable development education. there is a concern that the result might be a model of didactic values education rather that a more open-ended learner-centred approach. more positively, in learning for our future ( ), the aim of sustainable development education is described as that which will inform people’s values ‘through an exploration of the fundamental principles of the way we live our lives now and the impact our lifestyles have on the environment and society’ (p. ). competent to take action the four purposes outlined in a curriculum for excellence describe a vision of a young person as a confident, enthusiastic and committed individual who is able to evaluate issues and to take the initiative in finding and applying solutions to problems. this fits with robottom and hart’s ( ) description of critical environmental education, wherein students are supported in being able to take action for the environment. resources such as pathways: real schools, real experiences (wwf, ), provide exam- ples of pupils participating in planning for and taking action within the school, in environmental groups, school councils, and as part of wider school initiatives. through initiatives such as assessment is for learning (lts, ), teachers are being given strategies to enable pupils to be more pro-active in their own learning and to engage in self-evaluation and reflection on what they can do and what the next steps in their learning will be. however, a key barrier to progress in the achievement of more critical, action-based teaching and learning is the lack of provision of systematic and sustained in-service education. rauch ( ) acknowledges this: ‘teachers need greater willingness and ability to handle learning processes which are not a priori structured’ (p. ). realistically, current half-day or one-day ‘familiarization’ courses cannot achieve fundamental changes in attitude and understanding. additionally, gough ( ) suggests that, already, many pupils are far ahead of the curriculum in terms of environmental understanding and interests. d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton conclusions: sustainable development education—a curriculum for excellence? if the pedagogical values underpinning a curriculum for excellence impact on the design of the revised scottish curriculum, then there may be a chance that the aims for sustain- able development education set out in learning for life, and reiterated in learning for our future, could be addressed. more realistically, in a presentation available on the scottish environmental protection agency web site, lavery ( ) states that, at the time of writing, sustainable development education is uncoordinated, not fully inte- grated, and still very much dependent on the enthusiasm of individual schools and teachers. there is, then, some way to go. essentially, there is a need for teachers at all stages of their careers to be supported in their understanding and implementation of sustainable development education. sustainable development education: an international study (sdelg, ) suggests that in most of the eleven countries studied, including scotland, there remains what palmer ( ) described as the ‘fundamental curricular and pedagogical differences between environmental education and schooling’ (p. ). problems arise when trying to reconcile a problem-solving, action-based approach such as that required by sustainable development education, with a school curriculum focused on the acquisition of knowledge and the mastery of skills and concepts: that is, a process-based rather than a product-based pedagogy. however, it must also be acknowledged that in sustainable development education, there are knowl- edge and ideas to be acquired and skills to be mastered. there is a lack of research evidence that establishes, conclusively, the most beneficial ways of developing and delivering a systematic, progression-based yet process-based sustainable develop- ment education curriculum. this is indicative, perhaps, of the complex nature of sustainable development education. the many overlapping skills and concepts, together with the emotional/affective dimensions and the elusive nature of ‘values’ do not match themselves to a rigidly objectives-based, cognition and skills model of progression. an opportunity exists in scotland, to add to the body of knowledge through qual- itative research linked to sustainable development education curriculum develop- ment. there is a noticeable lack of teachers’ voices in the current research and writing on sustainable development education in scotland (and elsewhere). currently this is being addressed in some small way through a study based on the work of teachers, from both the primary and secondary sectors, who have completed a module on developing sustainable development education in their classrooms as part of a scottish chartered teacher masters degree at the university of strathclyde (mcnaughton, unpublished). although the research is at an early stage, the teachers in their evaluations have reported achievement of a range of learning outcomes, posi- tive comments from pupils and interest from colleagues. they have become enthusi- astic champions of sustainable development education within their schools. more studies of this kind might help to bolster the place and understanding of sustainable development education in scotland, and further afield. d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r sustainable development education in scottish schools in the review document, a curriculum for excellence: progress and proposals (secrb, ), the key messages include that space can be found for more depth and width of pupil experiences and that the curriculum can be unified so that, ‘activities such as … sustainable development can be built into the curriculum framework’ (p. ). however, in the scottish executive’s own paper, ambitious, excellent schools: progress report (scottish executive, ) there is no mention of this cross-cutting approach. instead, the emphasis is firmly on assessment and a new examination and qualifica- tions system, improving school discipline, benchmarking and accountability. there are mixed messages here and a danger, perhaps, of what chapman ( ), in discuss- ing curriculum development in new south wales described as, ‘the downgrading of a potentially significant environmental education initiative’ (p. ) in favour of the more conventional and politically attractive rhetoric of ‘raising standards’. these problems help highlight a more universal need to find a common vocabulary and a set of descriptors that can allow schools and pupils to demonstrate ‘excellence’ in exter- nal appraisal while remaining true to the educational philosophy underpinning the proposed curriculum reforms. it may be argued, then, that good sustainable development education lies at the heart of good education and vice versa: that sustainability issues provide the backdrop for all aspects of life—political and economic, social and environmental. palmer ( ) describes two key features hindering the progress of sustainable development education: the speed and evolution of the documentation of its aims, principles and theories by those with expertise; and the lack of effect of such documentation on everyday practice. with a curriculum for excellence, scotland has the opportunity to fully integrate sustainable development education into the revised curriculum. the sleeping beauty, now awake, may yet go on to rule the kingdom. notes . learning for life ( ) described a variation in terms, for example, environmental education, development education and sustainability education. the term environmental education was felt to be wide enough to cover all aspects of sustainable living therefore, the authors retained that term. however, in in the response document, a scottish strategy for environmental education ( ), the recommendation was that the phrase education for sustainable development (esd) be used. in , the scottish executive’s sustainable development education liaison group adopted sustainable development education as the preferred term, thus its use in this paper. . for further details, see sterling ( ). . similar end results, for similarly complex but albeit different reasons, led to the mothballing of england’s equivalent advisory and umbrella organization, the council for environmental education, in , following government inquiries into sustainable development education by the uk government’s environmental audit committee (eac) in – , and – (eac, , ). notes on contributor marie jeanne mcnaughton is a senior lecturer in the department of childhood and primary studies at the university of strathclyde, glasgow. she is the d ow nl oa de d b y: [m cn au gh to n, m ar ie j ea nn e] a t: : n ov em be r m. j. mcnaughton environmental studies coordinator on the b.ed. 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( ) taking learning outdoors, the scottish educational journal, ( ), p. . wwf ( ) pathways: a development framework for school sustainability (godalming, surrey, wwf-uk). university of groningen search for decays of neutral beauty mesons into four muons lhcb collaboration published in: journal of high energy physics doi: . /jhep ( ) important note: you are advised to consult the publisher's version (publisher's pdf) if you wish to cite from it. please check the document version below. document version publisher's pdf, also known as version of record publication date: link to publication in university of groningen/umcg research database citation for published version (apa): lhcb collaboration ( ). search for decays of neutral beauty mesons into four muons. journal of high energy physics, ( ), [ ]. https://doi.org/ . /jhep ( ) copyright other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like creative commons). take-down policy if you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. downloaded from the university of groningen/umcg research database (pure): http://www.rug.nl/research/portal. for technical reasons the number of authors shown on this cover page is limited to maximum. download date: - - https://doi.org/ . /jhep ( ) https://research.rug.nl/en/publications/search-for-decays-of-neutral-beauty-mesons-into-four-muons( db-eef - - c f-a d ccbee).html https://doi.org/ . /jhep ( ) j h e p ( ) published for sissa by springer received: november , revised: february , accepted: february , published: march , search for decays of neutral beauty mesons into four muons the lhcb collaboration e-mail: tobias.tekampe@cern.ch abstract: a search for the non-resonant decays b s → µ+µ−µ+µ− and b → µ+µ−µ+µ− is presented. the measurement is performed using the full run data set collected in proton-proton collisions by the lhcb experiment at the lhc. the data correspond to integrated luminosities of and fb− collected at centre-of-mass energies of and tev, respectively. no signal is observed and upper limits on the branching fractions of the non-resonant decays at % confidence level are determined to be b(b s → µ+µ−µ+µ−) < . × − , b(b → µ+µ−µ+µ−) < . × − . keywords: b physics, flavour changing neutral currents, hadron-hadron scattering (experiments), rare decay, supersymmetry arxiv eprint: . open access, copyright cern, for the benefit of the lhcb collaboration. article funded by scoap . doi: . /jhep ( ) mailto:tobias.tekampe@cern.ch https://arxiv.org/abs/ . http://dx.doi.org/ . /jhep ( ) j h e p ( ) contents introduction detector and simulation event selection selection efficiencies and systematic uncertainties normalisation results conclusion the lhcb collaboration introduction the rare decays b (s) → µ+µ−µ+µ− proceed through b→ d(s) flavour-changing neutral- current processes, which are strongly suppressed in the standard model (sm). in the main non-resonant sm amplitude, one muon pair is produced via amplitudes described by electroweak loop diagrams and the other is created by a virtual photon as shown in figure (a). the branching fraction of the non-resonant b s → µ+µ−µ+µ− decay is expected to be . × − [ ]. theories extending the sm can significantly enhance the b (s) → µ+µ−µ+µ− decay rate by contributions of new particles. for example, in minimal supersymmetric models (mssm), the decay can proceed via new scalar s and pseudoscalar p sgoldstino particles, which both decay into a dimuon final state as shown in figure (b). there are two types of couplings between sgoldstinos and sm fermions. type-i couplings describe interactions between a sgoldstino and two fermions, where the coupling strength is proportional to the fermion mass. type-ii couplings describe a four-particle vertex, where a scalar and a pseudoscalar sgoldstino interact with two fermions. branching fractions up to b(b s → sp) ≈ − and b(b → sp) ≈ − are possible [ ]. sgoldstinos can decay into a pair of photons or a pair of charged leptons [ ]. in this analysis the muonic decay is considered, as the coupling to electrons is smaller and the large τ-lepton mass limits the available phase space. the branching fractions of the sgoldstino decays strongly depend on the model parameters such as the sgoldstino mass and the supersymmetry breaking scale. in the search for Σ+→ pµ+µ− decays the hypercp collaboration found an excess of events, the inclusion of charge-conjugate processes is implied throughout. – – j h e p ( ) w t γ w γ, z d, s b̄ µ− µ+ µ− µ+ (a) s p s, d b̄ µ− µ+ µ− µ+ (b) s̄ w c̄ c s b̄ µ− µ+ µ− µ+ φ j/ψ (c) figure . feynman diagrams for (a) the non-resonant b (s) → µ+µ−µ+µ− decay, (b) a supersym- metric b (s) → s(→ µ+µ−)p(→ µ+µ−) decay and (c) the resonant b s → j/ψ (→ µ+µ−)φ(→ µ+µ−) decay (see text). which is consistent with the decay Σ+→ pp with p → µ+µ− and a pseudoscalar mass of m(p) = . ± . mev [ ]. so far only limits on the sm and mssm branching fractions at % confidence level have been measured by lhcb based on the data recorded in [ ] to be b(b s → µ+µ−µ+µ−) < . × − , b(b → µ+µ−µ+µ−) < . × − , b(b s → s(→ µ+µ−)p(→ µ+µ−)) < . × − , b(b → s(→ µ+µ−)p(→ µ+µ−)) < . × − . these limits are based on assumed sgoldstino masses of m(s) = . gev/c , which is ap- proximately the central value of the allowed mass range, and m(p) = . mev/c . the dominant sm decays of neutral b mesons into four muons proceed through res- onances like φ, j/ψ and ψ( s). the most frequent of these decays is b s → j/ψφ, where both the j/ψ and the φ mesons decay into a pair of muons, as shown in figure (c). in the following, this decay is referred to as the resonant decay mode and treated as a back- ground. from the product of the measured branching fractions of the underlying decays b(b s → j/ψφ), b(j/ψ → µ+µ−), and b(φ→ µ+µ−) [ ] its branching fraction is calculated to be ( . ± . ) × − . in this paper a search for the non-resonant sm process, and for the mssm-induced b (s) → µ+µ−µ+µ− decays is presented, using pp collision data recorded by the lhcb detec- tor during lhc run . potentially contributing sgoldstinos are assumed to be short lived, such that they do not form a displaced vertex. the analysed data correspond to integrated luminosities of and fb− collected at centre-of-mass energies of and tev, respec- tively. the branching fraction is measured relative to the decay b+→ j/ψ (→ µ+µ−)k+, which gives a clean signal with a precisely measured branching fraction [ ]. this yields a significant improvement compared to the previous measurement, where the use of the b → j/ψk∗ decay as normalisation mode resulted in a large systematic uncertainty originating from the s-wave fraction and the less precisely measured branching fraction. the advantage of normalising to a well-known b meson decay is that dominant systematic uncertainties originating mainly from the bb cross-section cancel in the ratio. – – j h e p ( ) detector and simulation the lhcb detector [ , ] is a single-arm forward spectrometer covering the pseudorapidity range < η < , designed for the study of particles containing b or c quarks. the detector includes a high-precision tracking system consisting of a silicon-strip vertex detector sur- rounding the pp interaction region, a large-area silicon-strip detector located upstream of a dipole magnet with a bending power of about tm, and three stations of silicon-strip detectors and straw drift tubes placed downstream of the magnet. the tracking system provides a measurement of momentum, p, of charged particles with a relative uncertainty that varies from . % at low momentum to . % at gev/c. the minimum distance of a track to a primary vertex (pv), the impact parameter, is measured with a resolution of ( + /pt) µm, where pt is the component of the momentum transverse to the beam, in gev/c. different types of charged hadrons are distinguished using information from two ring-imaging cherenkov (rich) detectors. photons, electrons and hadrons are identified by a calorimeter system consisting of scintillating-pad and preshower detectors, an elec- tromagnetic calorimeter and a hadronic calorimeter. muons are identified by a system composed of alternating layers of iron and multiwire proportional chambers. in the simulation, pp collisions are generated using pythia [ , ] with a specific lhcb configuration [ ]. decays of hadronic particles are described by evtgen [ ], in which final-state radiation is generated using photos [ ]. the interaction of the generated particles with the detector, and its response, are implemented using the geant toolkit [ , ] as described in ref. [ ]. event selection the online event selection is performed by a trigger, which consists of a hardware stage, based on information from the calorimeter and muon systems, followed by a software stage, which applies a full event reconstruction. in this analysis candidate events are first required to pass the hardware trigger, which for tev ( tev) data selects events with at least one muon with a transverse momentum of pt > . gev/c (pt > . gev/c) or at least one pair of muons with the product of the transverse momenta larger than ( . ) gev /c (( . ) gev /c ). in the subsequent software trigger, at least one of the final-state particles is required to have pt > gev/c and an impact parameter larger than µm with respect to all pvs in the event. in the offline selection, the b (s) decay vertex is constructed from four good quality muon candidates that form a common vertex and have a total charge of zero. the vertex is required to be significantly displaced from any pv. among the four final-state muons, there are four possible dimuon combinations with zero charge. in all four combinations, the mass windows corresponding to the φ ( – mev/c ), j/ψ ( – mev/c ) and ψ( s) ( – mev/c ) resonances are vetoed. this efficiently suppresses any background from any of the three mentioned resonances to a negligible level. contributions of other charmonium states are found to be negligible. – – j h e p ( ) the matrixnet (mn) [ ], a multivariate classifier based on a boosted decision tree [ , ], is applied in order to remove combinatorial background, where a candi- date b (s) vertex is constructed from four muons that do not originate from a single b meson decay. the input variables are the following properties of the b (s) candidate: the decay time, the vertex quality, the momentum and transverse momentum, the cosine of the direction angle (dira), and the smallest impact parameter chisquare (χ ip) with respect to any pv, where χ ip is defined as the difference between the vertex-fit χ of a pv recon- structed with and without the b (s) candidate. the dira is defined as the angle between the momentum of the reconstructed b (s) candidate and the vector from the pv with the smallest χ ip to the b (s) decay vertex. as training samples, simulated b s → µ+µ−µ+µ− and b → µ+µ−µ+µ− events, generated with a uniform probability across the decay phase space, are used as a signal proxy. before training, the signal simulation is weighted to correct for known discrepancies between data and simulation as described later. the back- ground sample is taken from the far and the near sidebands in data as defined in table . in order to verify that the classification of each event is unbiased, -fold cross-validation [ ] is employed. background arising from misidentifying one or more particles is suppressed by apply- ing particle identification (pid) requirements. information from the rich system, the calorimeters and the muon system is used to calculate the difference in log-likelihood be- tween the hypothesis of a final-state particle being a pion or a muon, dllµπ. events in the signal region are not examined until the analysis is finalised. events outside the signal region are split into the far sidebands, used to calculate the expected background yield, and the near sidebands, used to optimise the cuts on the mn response and the minimum dllµπ values of the four muon candidates in the final state. the optimization of the cuts is performed on a two-dimensional grid maximising the figure of merit [ ] fom = εsignal σ/ + √ n expected bkg ×εbkg . the intended significance in terms of standard deviations (σ) is set to three. very similar selection criteria are found when using five. the expected background yield before applying the mn and pid selection, n expected bkg , is determined from a fit to the events in the near sidebands using an exponential function. for each grid point the background efficiency, εbkg, is measured using events from the near sidebands. the signal efficiency, εsignal, is measured for each grid point using simulated b (s) → µ+µ−µ+µ− decays. lacking a model for non-resonant b (s) → µ+µ−µ+µ− simulation, the selection of the preceding measurement was developed on b s → j/ψ (→ µ+µ−)φ(→ µ+µ−) data. now that a suitable simulation model is available, significant improvements in terms of signal efficiency and background rejection are made by employing a multivariate classifier and being able to measure the selection efficiency from simulation. selection efficiencies and systematic uncertainties the optimal working point corresponds to signal efficiencies of ( . ± . )% and – – j h e p ( ) mass interval ( mev/c ) near sidebands [ , ] and [ , ] far sidebands [ , ] and [ , ] signal region [m(b ) − ,m(b s ) + ] b s search region [m(b s ) − ,m(b s ) + ] b search region [m(b ) − ,m(b ) + ] table . definitions of intervals in the b and b s reconstructed invariant mass distributions. ( . ± . )% for the b s → µ+µ−µ+µ− and b → µ+µ−µ+µ− decay modes, respec- tively. sources of peaking background such as b → k∗ µ+µ−, in which the kaon and the pion originating from the k∗ decay are misidentified as muons, are reduced to a negligible level by the optimised selection. the efficiencies for the mssm processes are measured using simulated samples of the b (s) → s(→ µ+µ−)p(→ µ+µ−) decays, where the b (s) me- son decays into a pseudoscalar sgoldstino with a mass of . mev/c [ ] and a scalar sgoldstino with a mass of . gev/c . both the p and s particles are simulated with a decay width of Γ = . mev/c , which corresponds to a prompt decay. the measured efficiencies are the same for the b s and the b decays and amount to ( . ± . )%. the difference between the sm and the mssm efficiencies originates from the fact that in the case of the decay proceeding via p and s sgoldstinos, the decay products are more likely to be within the acceptance of the lhcb detector. in order to test the dependence of the measured b (s) → s(→ µ+µ−)p(→ µ+µ−) branching fractions on the mass of the scalar sgoldstino, the selection efficiency is measured in bins of dimuon invariant mass while requiring the corresponding other dimuon mass to be between and mev/c . an efficiency variation of o( %) is observed. the selection applied to the normalisation mode b+→ j/ψ (→ µ+µ−)k+ differs from that applied to the signal modes in the pid criteria and that no multivariate analysis technique is applied. the total efficiency is ( . ± . )%. the uncertainties on the ef- ficiencies are driven by the limited number of simulated events and are treated as systematic uncertainties of . – . %. the total efficiency is calculated as the product of the efficiencies of the different stages of the selection. as an alternative to the trigger efficiency calculated on simulation, the value is calculated on b+ → j/ψ (→ µ+µ−)k+ data [ ] and a systematic uncertainty of % is assigned corresponding to the relative difference. the efficiency of the mn classifier to select the more frequent decay b s → j/ψ (→ µ+µ−)φ(→ k+k−) is compared between data and simulation. the relative difference of . % is assigned as a systematic uncertainty. another source of systematic uncertainty arises from the track finding efficiency. again, values obtained from data [ ] and simulation are compared and the deviation is treated as a correction factor for the efficiency, while the uncertainty on the deviation, . %, is assigned as a systematic uncertainty. in general the agreement in the observables used in the selection between data and simulation is very good, although there are some distributions that are known to deviate. – – j h e p ( ) therefore, the gradient boosting reweighting technique [ ] is used to calculate weights that correct for differences between data and simulation in b s → j/ψ (→ µ+µ−)φ(→ k+k−). the weighting is performed in the track multiplicity, the b transverse momentum, the χ of the decay vertex fit and the χ ip. the first two are chosen because they are correlated with the pid variables and the latter two dominate the feature ranking obtained from the mn training. these weights are applied to the b (s) → µ+µ−µ+µ− and b+→ j/ψ (→ µ+µ−)k+ simulation samples, and are used to calculate the mn and the pid efficiencies. in order to account for inaccuracies of this method resulting from the kinematic and topological differences between the decay modes, systematic uncertainties of . % are assigned based on the difference of the mn efficiency on b (s) → µ+µ−µ+µ− and b s → j/ψ (→ µ+µ−)φ(→ k+k−). for the b+ → j/ψ (→ µ+µ−)k+ decay mode, the efficiencies are measured with and without weights and the observed difference of . % is assigned as systematic uncertainty. in order to determine accurate efficiencies of the applied pid requirements, calibra- tion samples of muons from j/ψ → µ+µ− and φ → µ+µ− decays and of kaons from d∗+ → d (→ k−π+)π+ decays are used. the relative frequency for kaons and muons to pass the pid criteria is calculated in bins of track multiplicity, particle momentum and pseudorapidity. different binning schemes are tested and the observed differences in the efficiencies of % for b+→ j/ψ (→ µ+µ−)k+ and . % for b (s) → µ+µ−µ+µ− are assigned as systematic uncertainties. additionally, % of the simulated b (s) → µ+µ−µ+µ− decays contain muons with low transverse momentum outside the kinematic region covered by the calibration data. this fraction is assigned as a systematic uncertainty. candidates that have a reconstructed invariant mass within ± mev/c around the known b (s) mass, which corresponds to ± σ of the mass resolution, are treated as signal candidates. the ac- curacy of the efficiency of this cut is evaluated on b s → j/ψ (→ µ+µ−)φ(→ k+k−) data. a systematic uncertainty of . % corresponding to the relative difference of the efficiency measured on data and simulation is assigned. systematic uncertainties of . % and . % in the case of b (s) → µ+µ−µ+µ− and b+ → j/ψ (→ µ+µ−)k+ originate from the imper- fections of the efficiency of the event reconstruction due to soft photon radiation and . % from mismatching of track segments between different tracking stations in the detector, which is measured using simulated events. all relevant sources of systematic uncertainty along with the total values are summarised in table . the most significant improvements with regard to the preceding measurement are the larger available data sample, and the choice of the b+→ j/ψ (→ µ+µ−)k+ decay as normalisation mode, which has the advan- tage of a precisely measured branching fraction and the absence of an additional systematic uncertainty originating from the s-wave correction. normalisation the b+ → j/ψ (→ µ+µ−)k+ signal yield is determined by performing an unbinned ex- tended maximum likelihood fit to the k+µ+µ− invariant mass distribution. in this fit the j/ψ mass is constrained [ ] to the world average [ ]. the normalisation yield is found to be n(b+ → j/ψ (→ µ+µ−)k+) = ± . the j/ψk+ mass spectrum along – – j h e p ( ) ) c) (mev/ + kψ(j/m ) c e v e n ts / ( . m e v / lhcb + kψ j/→ + b combinatorial x + kψ j/→b figure . fit to the b+→ j/ψ (→ µ+µ−)k+ invariant mass distribution. the signal contribution is modelled by a hypatia [ ] function (blue dotted line), the combinatorial background by an exponential function (green dash-dotted line). partially reconstructed decays, such as b → j/ψk∗ where one pion is not reconstructed, are modelled by a gaussian function with an exponential tail towards the lower mass side (red dashed line). data are shown by black dots. with the fit result is shown in figure . a systematic uncertainty of . % is assigned to the determined b+→ j/ψ (→ µ+µ−)k+ yield by using an alternative fit model and performing a binned extended maximum likelihood fit. the b (s) → µ+µ−µ+µ− branching fraction is calculated as b(b (s)→ µ +µ−µ+µ−) = n(b (s)→ µ +µ−µ+µ−) ×ηd,s, with ηd,s = ε(b+→ j/ψ (→ µ+µ−)k+) ×b(b+→ j/ψ (→ µ+µ−)k+) ε(b (s) → µ+µ−µ+µ−) ×n(b+→ j/ψ (→ µ+µ−)k+) × fu fd,s , where n(b+→ j/ψ (→ µ+µ−)k+) and n(b (s) → µ+µ−µ+µ−) are the observed yields of the normalisation and the signal channel, respectively. the ratio between the production rates of b s and b was measured by lhcb to be fs/fd = . ± . [ ]. the measure- ment was performed using pp collision data at √ s = tev, but found to be stable between√ s = tev and tev by a previous lhcb measurement [ ]. the ratio between the b+ and b production rates is assumed to be unity. as a consequence fs/fu is equal to fs/fd. the single event sensitivities, ηd,s, amount ηsms = ( . ± . ) × − , ηsmd = ( . ± . ) × − , ηmssms = ( . ± . ) × − , ηmssmd = ( . ± . ) × − , – – j h e p ( ) for the b s and the b decay modes in the sm and in the mssm scenario. here, the uncertainties are the combined values of the statistical uncertainty on the b+ → j/ψ (→ µ+µ−)k+ yield and the systematic uncertainty. in the case of ηs the systematic uncertainty is dominated by the ratio of fu/fs and in the case of ηd by the weighting procedure applied to correct for the difference between data and simulation. the individual sources of systematic uncertainties given in table are assumed to be uncorrelated and are combined quadratically. the total systematic uncertainty is . % for the b s decay and . % for the b decay. these values are small compared to the statistical uncertainty on the expected number of background events in the b and b s search regions. the whole analysis strategy is cross-checked by measuring the b s → j/ψ (→ µ+µ−)φ(→ µ+µ−) branching fraction. the obtained value has a precision of % and is compatible with the product of the branching fractions of the underlying decays taken from ref. [ ]. the number of expected background events is determined by fitting an exponential function to the far sidebands of m(µ+µ−µ+µ−). extrapolating and integrating the fitted function in ± mev/c wide windows around the b (s) meson masses yields the number of expected background events, n expected bkg (b ) = . + . − . (stat) ± . (syst) and n expected bkg (b s ) = . + . − . (stat) ± . (syst). the statistical uncertainty is the combination of the poissonian uncertainty originating from the limited size of the data sample and the uncertainty on the fit parameters. as an alternative fit model a second-order polynomial is used and the difference between these background expectations is assigned as a systematic uncertainty. results the final distribution of the reconstructed mass of the four muon system is shown in figure . no candidates are observed in either the b or the b s search region, which is consistent with the expected background yield. the hybrid cls procedure [ – ], with log-normal priors to account for uncertainties of both background and efficiency estimations, is used to convert the observations into upper limits on the corresponding branching fractions. the exclusion at % confidence level assuming the sm single event sensitivities is shown in figure . the result for the corresponding mssm values is presented in figure . the limits on the branching fractions of the b s and b decays are anti-correlated. replacing the log-normal priors by gamma distributions yields the same results. assuming negligible cross-feed between the b s and the b search regions, the observed upper limits on the branching fractions at % confidence level are found to be b(b s → µ+µ−µ+µ−) < . × − , b(b → µ+µ−µ+µ−) < . × − , b(b s → s(→ µ+µ−)p(→ µ+µ−)) < . × − , b(b → s(→ µ+µ−)p(→ µ+µ−)) < . × − . – – j h e p ( ) source value [%] selection efficiency . − . trigger efficiency . mn efficiency . track finding efficiency . weighting b (s) → µ+µ−µ+µ− . weighting b+→ j/ψ (→ µ+µ−)k+ . pid binning b+→ j/ψ (→ µ+µ−)k+ . pid binning b (s) → µ+µ−µ+µ− . kinematic coverage of pid calibration data . ± mev/c search region efficiency . soft photon radiation b (s) → µ+µ−µ+µ− . soft photon radiation b+→ j/ψ (→ µ+µ−)k+ . track segments mismatching . normalisation fit . fu/fs . b(b+→ j/ψk+) . b(j/ψ → µ+µ−) . combined ηs sm . combined ηd sm . combined ηs mssm . combined ηd mssm . table . summary of systematic uncertainties affecting the single event sensitivities along with the total systematic uncertainty calculated by adding up the individual components in quadrature. the dominating uncertainty arising from fu/fs only contributes to ηs. the uncertainty of the stated selection efficiencies arising from the limited number of simulated events is . % for b → µ+µ−µ+µ− and . % for all other considered decay modes. conclusion in summary, a search for non-resonant b (s) → µ+µ−µ+µ− decays has been presented. in addition, the sensitivity to a specific mssm scenario has been probed. the applied selection focuses on finding four muon tracks that form a common vertex. for the sm scenario and the mssm decay through short-lived scalar and pseudoscalar new particles, the limits set by the previous measurement performed by lhcb on a subset of the present data, are improved by a factor of . ( . ) for the sm (mssm) mode in the case of the b s decay and by a factor of . ( . ) in the case of the b decay. – – j h e p ( ) figure . mass distribution of selected b (s) → µ+µ−µ+µ− events observed in fb− of data in all considered b mass regions. background (red line) is modelled by an exponential function. signal subregions for b and b s searches are also shown. the error bars on the individual points with n entries are ± √ n. ] − ×) [ − µ+ µ− µ+ µ→ s (bΒ ] − × ) [ − µ + µ − µ + µ → (b Β . . . . . . . . lhcb % cl exclusion observed σ ±expected σ ±expected figure . expected and observed % cl exclusion in b(b → µ+µ−µ+µ−) vs. b(b s → µ+µ−µ+µ−) parameters plane. acknowledgments we express our gratitude to our colleagues in the cern accelerator departments for the excellent performance of the lhc. we thank the technical and administrative staff at the lhcb institutes. we acknowledge support from cern and from the national – – j h e p ( ) ] − ×) [ − µ+ µ→(pΒ ×) − µ+ µ →(sΒ × s p) → s (bΒ ] − × ) [ − µ + µ → (p Β × ) − µ + µ → (s Β × s p ) → (b Β . . . . . . . . lhcb s p→ s s p; b→ b − µ+ µ →; p − µ+ µ →s = mev p = . gev; msm % cl exclusion observed σ ±expected σ ±expected figure . expected and observed % cl exclusion in b(b → s(→ µ+µ−)p(→ µ+µ−)) vs. b(b s → s(→ µ+µ−)p(→ µ+µ−)) parameters plane with scalar and pseudoscalar s and p as described in section . agencies: capes, cnpq, faperj and finep (brazil); nsfc (china); cnrs/in p (france); bmbf, dfg and mpg (germany); infn (italy); fom and nwo (the nether- lands); mnisw and ncn (poland); men/ifa (romania); mines and faso (russia); mineco (spain); snsf and ser (switzerland); nasu (ukraine); stfc (united king- dom); nsf (u.s.a.). we acknowledge the computing resources that are provided by cern, in p (france), kit and desy (germany), infn (italy), surf (the netherlands), pic (spain), gridpp (united kingdom), rrcki and yandex llc (russia), cscs (switzer- land), ifin-hh (romania), cbpf (brazil), pl-grid (poland) and osc (u.s.a.). we are indebted to the communities behind the multiple open source software packages on which we depend. individual groups or members have received support from avh foundation (ger- many), eplanet, marie sk lodowska-curie actions and erc (european union), conseil général de haute-savoie, labex enigmass and ocevu, région auvergne (france), rfbr and yandex llc (russia), gva, xuntagal and gencat (spain), herchel smith fund, the royal society, royal commission for the exhibition of and the leverhulme trust (united kingdom). open access. this article is distributed under the terms of the creative commons attribution license (cc-by . ), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited. references [ ] y. dincer and l.m. sehgal, electroweak effects in the double dalitz decay bs → `+`−`′+`′−, phys. lett. b ( ) [hep-ph/ ] [inspire]. – – http://creativecommons.org/licenses/by/ . / http://dx.doi.org/ . /s - ( ) -x https://arxiv.org/abs/hep-ph/ http://inspirehep.net/search?p=find+eprint+hep-ph/ j h e p ( ) [ ] s.v. demidov and d.s. gorbunov, flavor violating processes with sgoldstino pair production, phys. rev. d ( ) [arxiv: . ] [inspire]. 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/s - ( ) - http://dx.doi.org/ . /s - ( ) - https://arxiv.org/abs/hep-ex/ http://inspirehep.net/search?p=find+eprint+hep-ex/ j h e p ( ) the lhcb collaboration r. aaij , b. adeva , m. adinolfi , z. ajaltouni , s. akar , j. albrecht , f. alessio , m. alexander , s. ali , g. alkhazov , p. alvarez cartelle , a.a. alves jr , s. amato , s. amerio , y. amhis , l. an , l. anderlini , g. andreassi , m. andreotti ,g, j.e. andrews , r.b. appleby , f. archilli , p. d’argent , j. arnau romeu , a. artamonov , m. artuso , e. aslanides , g. auriemma , m. baalouch , i. babuschkin , s. bachmann , j.j. back , a. badalov , c. baesso , s. baker , w. baldini , a. baranov , r.j. barlow , c. barschel , s. barsuk , w. barter , m. baszczyk , v. batozskaya , b. batsukh , v. battista , a. bay , l. beaucourt , j. beddow , f. bedeschi , i. bediaga , l.j. bel , v. bellee , n. belloli ,i, k. belous , i. belyaev , e. ben-haim , g. bencivenni , s. benson , j. benton , a. berezhnoy , r. bernet , a. bertolin , c. betancourt , f. betti , m.-o. bettler , m. van beuzekom , ia. bezshyiko , s. bifani , p. billoir , t. bird , a. birnkraut , a. bitadze , a. bizzeti ,u, t. blake , f. blanc , j. blouw ,†, s. blusk , v. bocci , t. boettcher , a. bondar ,w, n. bondar , , w. bonivento , i. bordyuzhin , a. borgheresi ,i, s. borghi , m. borisyak , m. borsato , f. bossu , m. boubdir , t.j.v. bowcock , e. bowen , c. bozzi , , s. braun , m. britsch , t. britton , j. brodzicka , e. buchanan , c. burr , a. bursche , j. buytaert , s. cadeddu , r. calabrese ,g, m. calvi ,i, m. calvo gomez ,m, a. camboni , p. campana , d.h. campora perez , l. capriotti , a. carbone ,e, g. carboni ,j, r. cardinale ,h, a. cardini , p. carniti ,i, l. carson , k. carvalho akiba , g. casse , l. cassina ,i, l. castillo garcia , m. cattaneo , ch. cauet , g. cavallero , r. cenci ,t, d. chamont , m. charles , ph. charpentier , g. chatzikonstantinidis , m. chefdeville , s. chen , s.-f. cheung , v. chobanova , m. chrzaszcz , , x. cid vidal , g. ciezarek , p.e.l. clarke , m. clemencic , h.v. cliff , j. closier , v. coco , j. cogan , e. cogneras , v. cogoni , ,f , l. cojocariu , g. collazuol ,o, p. collins , a. comerma-montells , a. contu , a. cook , g. coombs , s. coquereau , g. corti , m. corvo ,g, c.m. costa sobral , b. couturier , g.a. cowan , d.c. craik , a. crocombe , m. cruz torres , s. cunliffe , r. currie , c. d’ambrosio , f. da cunha marinho , e. dall’occo , j. dalseno , p.n.y. david , a. davis , o. de aguiar francisco , k. de bruyn , s. de capua , m. de cian , j.m. de miranda , l. de paula , m. de serio ,d, p. de simone , c.-t. dean , d. decamp , m. deckenhoff , l. del buono , m. demmer , a. dendek , d. derkach , o. deschamps , f. dettori , b. dey , a. di canto , h. dijkstra , f. dordei , m. dorigo , a. dosil suárez , a. dovbnya , k. dreimanis , l. dufour , g. dujany , k. dungs , p. durante , r. dzhelyadin , a. dziurda , a. dzyuba , n. déléage , s. easo , m. ebert , u. egede , v. egorychev , s. eidelman ,w, s. eisenhardt , u. eitschberger , r. ekelhof , l. eklund , s. ely , s. esen , h.m. evans , t. evans , a. falabella , n. farley , s. farry , r. fay , d. fazzini ,i, d. ferguson , a. fernandez prieto , f. ferrari , , f. ferreira rodrigues , m. ferro-luzzi , s. filippov , r.a. fini , m. fiore ,g, m. fiorini ,g, m. firlej , c. fitzpatrick , t. fiutowski , f. fleuret ,b, k. fohl , m. fontana , , f. fontanelli ,h, d.c. forshaw , r. forty , v. franco lima , m. frank , c. frei , j. fu ,q, e. furfaro ,j, c. färber , a. gallas torreira , d. galli ,e, s. gallorini , s. gambetta , m. gandelman , p. gandini , y. gao , l.m. garcia martin , j. garćıa pardiñas , j. garra tico , l. garrido , p.j. garsed , d. gascon , c. gaspar , l. gavardi , g. gazzoni , d. gerick , e. gersabeck , m. gersabeck , t. gershon , ph. ghez , s. giaǹı , v. gibson , o.g. girard , l. giubega , k. gizdov , v.v. gligorov , d. golubkov , a. golutvin , , a. gomes ,a, i.v. gorelov , c. gotti ,i, m. grabalosa gándara , r. graciani diaz , l.a. granado cardoso , e. graugés , – – j h e p ( ) e. graverini , g. graziani , a. grecu , p. griffith , l. grillo , ,i, b.r. gruberg cazon , o. grünberg , e. gushchin , yu. guz , t. gys , c. göbel , t. hadavizadeh , c. hadjivasiliou , g. haefeli , c. haen , s.c. haines , s. hall , b. hamilton , x. han , s. hansmann-menzemer , n. harnew , s.t. harnew , j. harrison , m. hatch , j. he , t. head , a. heister , k. hennessy , p. henrard , l. henry , j.a. hernando morata , e. van herwijnen , m. heß , a. hicheur , d. hill , c. hombach , h. hopchev , w. hulsbergen , t. humair , m. hushchyn , n. hussain , d. hutchcroft , m. idzik , p. ilten , r. jacobsson , a. jaeger , j. jalocha , e. jans , a. jawahery , f. jiang , m. john , d. johnson , c.r. jones , c. joram , b. jost , n. jurik , s. kandybei , w. kanso , m. karacson , j.m. kariuki , s. karodia , m. kecke , m. kelsey , i.r. kenyon , m. kenzie , t. ketel , e. khairullin , b. khanji , c. khurewathanakul , t. kirn , s. klaver , k. klimaszewski , s. koliiev , m. kolpin , i. komarov , r.f. koopman , p. koppenburg , a. kosmyntseva , a. kozachuk , m. kozeiha , l. kravchuk , k. kreplin , m. kreps , p. krokovny ,w, f. kruse , w. krzemien , w. kucewicz ,l, m. kucharczyk , v. kudryavtsev ,w, a.k. kuonen , k. kurek , t. kvaratskheliya , , d. lacarrere , g. lafferty , a. lai , g. lanfranchi , c. langenbruch , t. latham , c. lazzeroni , r. le gac , j. van leerdam , j.-p. lees , a. leflat , , j. lefrançois , r. lefèvre , f. lemaitre , e. lemos cid , o. leroy , t. lesiak , b. leverington , y. li , t. likhomanenko , , r. lindner , c. linn , f. lionetto , b. liu , x. liu , d. loh , i. longstaff , j.h. lopes , d. lucchesi ,o, m. lucio martinez , h. luo , a. lupato , e. luppi ,g, o. lupton , a. lusiani , x. lyu , f. machefert , f. maciuc , o. maev , k. maguire , s. malde , a. malinin , t. maltsev , g. manca , g. mancinelli , p. manning , j. maratas ,v, j.f. marchand , u. marconi , c. marin benito , p. marino ,t, j. marks , g. martellotti , m. martin , m. martinelli , d. martinez santos , f. martinez vidal , d. martins tostes , l.m. massacrier , a. massafferri , r. matev , a. mathad , z. mathe , c. matteuzzi , a. mauri , b. maurin , a. mazurov , m. mccann , j. mccarthy , a. mcnab , r. mcnulty , b. meadows , f. meier , m. meissner , d. melnychuk , m. merk , a. merli ,q, e. michielin , d.a. milanes , m.-n. minard , d.s. mitzel , a. mogini , j. molina rodriguez , i.a. monroy , s. monteil , m. morandin , p. morawski , a. mordà , m.j. morello ,t, j. moron , a.b. morris , r. mountain , f. muheim , m. mulder , m. mussini , d. müller , j. müller , k. müller , v. müller , p. naik , t. nakada , r. nandakumar , a. nandi , i. nasteva , m. needham , n. neri , s. neubert , n. neufeld , m. neuner , a.d. nguyen , t.d. nguyen , c. nguyen-mau ,n, s. nieswand , r. niet , n. nikitin , t. nikodem , a. novoselov , d.p. o’hanlon , a. oblakowska-mucha , v. obraztsov , s. ogilvy , r. oldeman , c.j.g. onderwater , j.m. otalora goicochea , a. otto , p. owen , a. oyanguren , , p.r. pais , a. palano ,d, f. palombo ,q, m. palutan , j. panman , a. papanestis , m. pappagallo ,d, l.l. pappalardo ,g, w. parker , c. parkes , g. passaleva , a. pastore ,d, g.d. patel , m. patel , c. patrignani ,e, a. pearce , , a. pellegrino , g. penso , m. pepe altarelli , s. perazzini , p. perret , l. pescatore , k. petridis , a. petrolini ,h, a. petrov , m. petruzzo ,q, e. picatoste olloqui , b. pietrzyk , m. pikies , d. pinci , a. pistone , a. piucci , s. playfer , m. plo casasus , t. poikela , f. polci , a. poluektov , , i. polyakov , e. polycarpo , g.j. pomery , a. popov , d. popov , , b. popovici , s. poslavskii , c. potterat , e. price , j.d. price , j. prisciandaro , a. pritchard , c. prouve , v. pugatch , a. puig navarro , g. punzi ,p, w. qian , r. quagliani , , b. rachwal , j.h. rademacker , m. rama , m. ramos pernas , m.s. rangel , i. raniuk , f. ratnikov , g. raven , f. redi , s. reichert , a.c. dos reis , c. remon alepuz , v. renaudin , s. ricciardi , s. richards , m. rihl , k. rinnert , – – j h e p ( ) v. rives molina , p. robbe , , a.b. rodrigues , e. rodrigues , j.a. rodriguez lopez , p. rodriguez perez ,†, a. rogozhnikov , s. roiser , a. rollings , v. romanovskiy , a. romero vidal , j.w. ronayne , m. rotondo , m.s. rudolph , t. ruf , p. ruiz valls , j.j. saborido silva , e. sadykhov , n. sagidova , b. saitta ,f , v. salustino guimaraes , c. sanchez mayordomo , b. sanmartin sedes , r. santacesaria , c. santamarina rios , m. santimaria , e. santovetti ,j, a. sarti ,k, c. satriano ,s, a. satta , d.m. saunders , d. savrina , , s. schael , m. schellenberg , m. schiller , h. schindler , m. schlupp , m. schmelling , t. schmelzer , b. schmidt , o. schneider , a. schopper , k. schubert , m. schubiger , m.-h. schune , r. schwemmer , b. sciascia , a. sciubba ,k, a. semennikov , a. sergi , n. serra , j. serrano , l. sestini , p. seyfert , m. shapkin , i. shapoval , y. shcheglov , t. shears , l. shekhtman ,w, v. shevchenko , b.g. siddi , , r. silva coutinho , l. silva de oliveira , g. simi ,o, s. simone ,d, m. sirendi , n. skidmore , t. skwarnicki , e. smith , i.t. smith , j. smith , m. smith , h. snoek , m.d. sokoloff , f.j.p. soler , b. souza de paula , b. spaan , p. spradlin , s. sridharan , f. stagni , m. stahl , s. stahl , p. stefko , s. stefkova , o. steinkamp , s. stemmle , o. stenyakin , s. stevenson , s. stoica , s. stone , b. storaci , s. stracka ,p, m. straticiuc , u. straumann , l. sun , w. sutcliffe , k. swientek , v. syropoulos , m. szczekowski , t. szumlak , s. t’jampens , a. tayduganov , t. tekampe , m. teklishyn , g. tellarini ,g, f. teubert , e. thomas , j. van tilburg , m.j. tilley , v. tisserand , m. tobin , s. tolk , l. tomassetti ,g, d. tonelli , s. topp-joergensen , f. toriello , e. tournefier , s. tourneur , k. trabelsi , m. traill , m.t. tran , m. tresch , a. trisovic , a. tsaregorodtsev , p. tsopelas , a. tully , n. tuning , a. ukleja , a. ustyuzhanin ,x, u. uwer , c. vacca ,f , v. vagnoni , , a. valassi , s. valat , g. valenti , a. vallier , r. vazquez gomez , p. vazquez regueiro , s. vecchi , m. van veghel , j.j. velthuis , m. veltri ,r, g. veneziano , a. venkateswaran , m. vernet , m. vesterinen , b. viaud , d. vieira , m. vieites diaz , h. viemann , x. vilasis-cardona ,m, m. vitti , v. volkov , a. vollhardt , b. voneki , a. vorobyev , v. vorobyev ,w, c. voß , j.a. de vries , c. vázquez sierra , r. waldi , c. wallace , r. wallace , j. walsh , j. wang , d.r. ward , h.m. wark , n.k. watson , d. websdale , a. weiden , m. whitehead , j. wicht , g. wilkinson , , m. wilkinson , m. williams , m.p. williams , m. williams , t. williams , f.f. wilson , j. wimberley , j. wishahi , w. wislicki , m. witek , g. wormser , s.a. wotton , k. wraight , k. wyllie , y. xie , z. xing , z. xu , z. yang , y. yao , h. yin , j. yu , x. yuan ,w, o. yushchenko , k.a. zarebski , m. zavertyaev ,c, l. zhang , y. zhang , y. zhang , a. zhelezov , y. zheng , a. zhokhov , x. zhu , v. zhukov , s. zucchelli centro brasileiro de pesquisas f́ısicas (cbpf), rio de janeiro, brazil universidade federal do rio de janeiro (ufrj), rio de janeiro, brazil center for high energy physics, tsinghua university, beijing, china lapp, université savoie mont-blanc, cnrs/in p , annecy-le-vieux, france clermont université, université blaise pascal, cnrs/in p , lpc, clermont-ferrand, france cppm, aix-marseille université, cnrs/in p , marseille, france lal, université paris-sud, cnrs/in p , orsay, france lpnhe, université pierre et marie curie, université paris diderot, cnrs/in p , paris, france i. physikalisches institut, rwth aachen university, aachen, germany fakultät physik, technische universität dortmund, dortmund, germany max-planck-institut für kernphysik (mpik), heidelberg, germany physikalisches institut, ruprecht-karls-universität heidelberg, heidelberg, germany school of physics, university college dublin, dublin, ireland sezione infn di bari, bari, italy – – j h e p ( ) sezione infn di bologna, bologna, italy sezione infn di cagliari, cagliari, italy sezione infn di ferrara, ferrara, italy sezione infn di firenze, firenze, italy laboratori nazionali dell’infn di frascati, frascati, italy sezione infn di genova, genova, italy sezione infn di milano bicocca, milano, italy sezione infn di milano, milano, italy sezione infn di padova, padova, italy sezione infn di pisa, pisa, italy sezione infn di roma tor vergata, roma, italy sezione infn di roma la sapienza, roma, italy henryk niewodniczanski institute of nuclear physics polish academy of sciences, kraków, poland agh — university of science and technology, faculty of physics and applied computer science, kraków, poland national center for nuclear research (ncbj), warsaw, poland horia hulubei national institute of physics and nuclear engineering, bucharest-magurele, romania petersburg nuclear physics institute (pnpi), gatchina, russia institute of theoretical and experimental physics (itep), moscow, russia institute of nuclear physics, moscow state university (sinp msu), moscow, russia institute for nuclear research of the russian academy of sciences (inr ran), moscow, russia yandex school of data analysis, moscow, russia budker institute of nuclear physics (sb ras), novosibirsk, russia institute for high energy physics (ihep), protvino, russia iccub, universitat de barcelona, barcelona, spain universidad de santiago de compostela, santiago de compostela, spain european organization for nuclear research (cern), geneva, switzerland insitute of physics, ecole polytechnique fédérale de lausanne (epfl), lausanne, switzerland physik-institut, universität zürich, zürich, switzerland nikhef national institute for subatomic physics, amsterdam, the netherlands nikhef national institute for subatomic physics and vu university amsterdam, amsterdam, the netherlands nsc kharkiv institute of physics and technology (nsc kipt), kharkiv, ukraine institute for nuclear research of the national academy of sciences (kinr), kyiv, ukraine university of birmingham, birmingham, united kingdom h.h. wills physics laboratory, university of bristol, bristol, united kingdom cavendish laboratory, university of cambridge, cambridge, united kingdom department of physics, university of warwick, coventry, united kingdom stfc rutherford appleton laboratory, didcot, united kingdom school of physics and astronomy, university of edinburgh, edinburgh, united kingdom school of physics and astronomy, university of glasgow, glasgow, united kingdom oliver lodge laboratory, university of liverpool, liverpool, united kingdom imperial college london, london, united kingdom school of physics and astronomy, university of manchester, manchester, united kingdom department of physics, university of oxford, oxford, united kingdom massachusetts institute of technology, cambridge, ma, united states university of cincinnati, cincinnati, oh, united states university of maryland, college park, md, united states syracuse university, syracuse, ny, united states pontif́ıcia universidade católica do rio de janeiro (puc-rio), rio de janeiro, brazil, associated to – – j h e p ( ) university of chinese academy of sciences, beijing, china, associated to school of physics and technology, wuhan university, wuhan, china, associated to institute of particle physics, central china normal university, wuhan, hubei, china, associated to departamento de fisica , universidad nacional de colombia, bogota, colombia, associated to institut für physik, universität rostock, rostock, germany, associated to national research centre kurchatov institute, moscow, russia, associated to instituto de fisica corpuscular (ific), universitat de valencia-csic, valencia, spain, associated to van swinderen institute, university of groningen, groningen, the netherlands, associated to a universidade federal do triângulo mineiro (uftm), uberaba-mg, brazil b laboratoire leprince-ringuet, palaiseau, france c p.n. lebedev physical institute, russian academy of science (lpi ras), moscow, russia d università di bari, bari, italy e università di bologna, bologna, italy f università di cagliari, cagliari, italy g università di ferrara, ferrara, italy h università di genova, genova, italy i università di milano bicocca, milano, italy j università di roma tor vergata, roma, italy k università di roma la sapienza, roma, italy l agh — university of science and technology, faculty of computer science, electronics and telecommunications, kraków, poland m lifaels, la salle, universitat ramon llull, barcelona, spain n hanoi university of science, hanoi, viet nam o università di padova, padova, italy p università di pisa, pisa, italy q università degli studi di milano, milano, italy r università di urbino, urbino, italy s università della basilicata, potenza, italy t scuola normale superiore, pisa, italy u università di modena e reggio emilia, modena, italy v iligan institute of technology (iit), iligan, philippines w novosibirsk state university, novosibirsk, russia x moscow institute of physics and technology, moscow, russia †deceased – – introduction detector and simulation event selection selection efficiencies and systematic uncertainties normalisation results conclusion the lhcb collaboration lincoln, t. and madgin, r. ( ) the inherent malleability of heritage: creating china’s beautiful villages. international journal of heritage studies, (doi: . / . . ) this is the author’s final accepted version. there may be differences between this version and the published version. you are advised to consult the publisher’s version if you wish to cite from it. http://eprints.gla.ac.uk/ / deposited on: february enlighten – research publications by members of the university of glasgow http://eprints.gla.ac.uk http://dx.doi.org/ . / . . http://eprints.gla.ac.uk/ / http://eprints.gla.ac.uk/ the inherent malleability of heritage: creating china’s beautiful villages toby lincoln, lecturer chinese urban history, university of leicester. rebecca madgin, senior lecturer urban development and management, university of glasgow. abstract the beautiful villages policy is a major policy initiative to secure the socio-economic and environmental development of china. tracking the development of this policy at a local level reveals the intricacies of policy making, the extent of local autonomy, and the ways in which rural development is delivered. contained within this is an examination of the evolving role of heritage within a policy framework that primarily focuses on the natural environment. this article traces the ways in which heritage became a component of this policy in one village in zhejiang province. it examines how the value of heritage was gradually realised by government officials and villagers, and how the concept of ecology was broadened to include built heritage, which ensures that funds can be accessed to stimulate rural development. in so doing the article investigates the concept of adaptive governance advanced by sebastian heilmann and elizabeth perry in the context of the inherent malleability of heritage as both a concept and a process. focusing on the ways in which institutions recognise and then mobilise heritage to secure instrumental goals enables us to examine the inherent malleability of heritage and how this is aligned to meet specific policy goals in china, as it is around the world. acknowledgements the authors would like to thank professor zhang weiliang at hangzhou normal university for assistance with arranging interviews, and zhou yang for help with translating and transcribing interviews. this work was supported by the: research incentivisation fund at the university of glasgow. university of leicester college of social sciences, arts and humanities research development fund. introduction that heritage ‘is continually subject to interpretation and reinterpretation, claim and counter claim, and negotiation’ (harrison , ) is axiomatic. however, less is known about the complexity of intra-governmental relations and how this affects the processes of re-interpretation and therefore the future of historic buildings. this article examines how the concept of heritage is re-interpreted at the provincial, county, town, and village levels in china and how this informs rural development. more specifically, the article explores the processes through which heritage is mobilised as part of a broader desire to secure the socio-economic development of the village of shuangyi near hangzhou in eastern china. in so doing it calls for a greater emphasis to be placed on the role of heritage within broader social, economic, and environmental policies. moreover, it focuses on the place of heritage within environmental and ecological policies, and so engages with winter’s belief that we need to consider the ways in which heritage ‘has a stake in, and can act as a positive enabler for, the complex, multi-vector challenges that face us today, such as cultural and environmental sustainability…’ ( , ). rather than see heritage as located purely within the domains of cultural heritage protection, museums, world heritage sites, and tourism this article demonstrates the ways in which heritage has been reconceptualised to fit a range of policy agendas that at first glance may not appear to be directly concerned with heritage. to engage with this context, this article explores the process of heritage conservation in shuangyi within the context of the zhongguo meili xiangcun (chinese beautiful villages, hereafter cbv) policy. it explains the wider policy environment, explores how it is implemented at the local level, and investigates how heritage is conceived within its context. we argue that in anji county heritage is subsumed within the wider notion of ecology as set out in cbv. the fact that this policy is not explicitly designed to protect heritage means that it is open to interpretation by different actors and reveals the ways in which heritage is moulded to fit different agendas. while both policy context and the political culture in which the discourses of history and heritage are conceived in china are top down, there is space for local actors. such local policy developments are often seen in the context of economic growth, and mobilized to support the idea of a corporate or entrepreneurial chinese state (duckett ; oi , ). we do not seek to deny that economic development is a key objective of cbv, but instead focus on the ways in which heritage is mobilised to align with a range of different policy agendas. case study site and methods the village of shuangyi in anji county to the northwest of hangzhou city in zhejiang province comprises households with people, nearly of whom are over the age of . it boasts a two-thousand year old history going back to the han dynasty that more recently includes japanese occupation during world war ii and suffering during the political campaigns of the great leap forward and the cultural revolution. however, since the beginning of the reform era in , the village has prospered, with per capita income at , yuan (c. us$ , ). shuangyi boasts a rich architectural and social history, which are both now being recognised as heritage, and used to support continuing development. the li, zhu and fang families have long lived in the village, and although the li family ancestral hall was destroyed by the japanese, the zhu hall survives to this day. apart from the ancestral hall, there are buildings surviving from the late qing dynasty ( - ), republican ( - ), and maoist ( - ) eras. in addition, the village has a variety of old monuments, including a spring, trees and grave sites. it sits in an area of natural beauty, surrounded by a bamboo forest, and close to a reservoir. this means that bamboo is an important agricultural sideline, and as in the county as a whole, aside from farming it is the most important source of income for villagers (anji dipuzhen shuangyi cun , , ). shuangyi is rich in resources, and yet like villages across china, it faces the pressures of urbanization. although its remoteness means that it is not in danger of being swallowed up by the seemingly ever-expanding city of hangzhou, scarcity of jobs in the village poses risks to its ongoing sustainability. many old houses were abandoned when families moved out, and some have already been demolished because they were seen as too dilapidated. the village leadership gradually came to recognise the value of heritage, and with county and provincial government support, is looking to develop this, along with industry and agriculture, to ensure that the village has a sustainable future. in order to examine our overarching research question, the place of heritage within cbv policy, we adopted a qualitative methodology. this took the form of semi-structured interviews which lasted, on average, . hours. in total we interviewed five government officials and four villagers. government officials were recruited through a gatekeeper at hangzhou normal university based on the authors’ criteria that each official played a key role in the delivery of cbv in the province and an awareness of heritage policy. a snowball approach was then adopted as government officials purposively selected the villagers on the authors’ pre-condition that each of the villagers had lived in shuangyi for the entirety of their lives. all the interviews took place in the same month and therefore at the same stage of the development of cbv in shuangyi. to inform both the interviews and the analysis the researchers analysed a large body of extant archival material including planning documents, guidelines, laws, and exhibition materials. our thematic analysis of both the archival material and the interview transcripts was based on inductive reasoning in which codes were assigned and agreed by the authors. we begin by outlining the inherent malleability of heritage in the context of heilmann and perry’s work on guerrilla policy style and adaptive governance. we then describe the development of cbv, exploring how heritage has been incorporated into the policy’s ecological objectives, consider the kinds of tensions that this process of recognition and reconceptualisation has produced, and finally conclude by discussing their negotiation within the context of adaptive governance. malleable heritage and adaptive governance in china whilst it is axiomatic that heritage is malleable, it is the ways in which the past can be moulded to fit the present that is the subject of this article. to achieve this, we centre the analysis on the traditions of governance within china and in particular within zhejiang province. existing research concerning the authorised heritage discourse (ahd) (smith ) and the belief that heritage is a ‘mental construct’ (logan et al , ) remain relevant but the focus is on understanding the processes through which heritage can be moulded to fit policy agendas within a specific mode of governance in china. in china, this process of constructing the ahd has been underway for longer than many acknowledge. in the first half of the twentieth century, often at the behest of government officials, temples, ancestral halls, shrines, pagodas, and other vestiges of history became tourist sites or educational institutions (yue-dong , - ; nedostup , - ; lincoln , - ). after , the chinese communist party (ccp), which was more intrusive than the republican government that preceded it, repurposed these spaces, and they were often damaged during the cultural revolution. in the reform era, despite government opposition, tangible heritage such as temples and ancestral halls have once more been used for religious and other long-practised communal purposes. in many cases though, heritage has been adapted and utilised to facilitate social change (svennson , - ; zhang and wu ). however, despite the overbearing nature of the chinese state, at least in comparison with liberal democracies, heritage is still malleable, and offers the opportunity for different actors to assert their claims to its meaning (silverman and blumenfield , ). part of the reason for this is the traditions of governance that have emerged within the chinese communist party. acknowledging their importance in the process of producing heritage highlights how recent tensions between theorising heritage across east and west can be seen as part of a move to decentre the anglo-centric and global north focus of many established theories (winter ). moving beyond these totalising theories necessitates that scholarship attempts to ground any perceived differences within the traditions of governance apparent within each country instead of speculating on broad theoretical differences across and between continents. rather than seek to universalise heritage practices around the how and the why this article instead engages with the traditions of governance at play within the specific rural chinese context in which the case study is located. to be sure, policies governing heritage in china have been partly defined by anglo-centric norms as evidenced through the increasing number of world heritage sites in the country, although of course these also serve chinese political and economic agendas. beyond this, the chinese government has surveyed heritage sites, and established government institutions to protect both tangible and intangible heritage (silverman and blumenfield , - ). it is clear then that the malleability of heritage means that it diverges from anglo-centric norms, even when its ahd is defined in part by those very norms and international organizations that exist to ensure its conservation. however, shuangyi is not a unesco world heritage site, while its buildings do not have the same level of protection as nationally important sites, or even those that municipal governments in shanghai and other large cities may deem worthy of protection. this means that heritage conservation in this village and thousands of others like it across china, happens within a policy context that may not be specifically designed to deal with it. this occurs because of the particular traditions of governance in china, and, in line with winter’s belief on the need to see heritage as part of broader global issues ( ), it links rural heritage to a growing emphasis on ecological development. in shuangyi, what constitutes heritage is broad and open to multiple interpretations within the context of the needs of cbv, while the process of re-using historic structures is shaped by the nature of policy making and implementation in china. the recognition and reconceptualization of heritage to align with cbv is, we argue, an example of what sebastian heilmann and elizabeth perry have termed a guerrilla policy style. this has its roots in the ccp’s history of guerrilla warfare and revolutionary mobilization in the s and s, and is characterized by pragmatism, adaptability, experimentation, and minimization of risk through the launching of new campaigns. it leads to a dictatorial style of governance, but also allows for considerable local autonomy (heilmann and perry ). a key aspect of this type of policy making and delivery rests with what heilmann and perry term adaptive governance which ‘depends upon people’s readiness to venture forth into unfamiliar environments to act, experiment, and learn from changing circumstances’ (heilmann and perry , ). furthermore, this style of policy making requires a high degree of fluidity and manoeuvrability, the ability to continually improvise and adjust policies, the use of practical experience of existing policies as a guide to determining future action, local officials having significant scope to implement decisions from the higher levels, and above all, the ability to search out new initiatives for development (heilmann and perry , - ). each of these aspects can be seen within the trajectory of cbv in shuangyi and form the basis for the analysis. the beautiful villages policy cbv was originally proposed by anji county in , and like any policy initiative it has its antecedents and inspirations. ecological aspects of the policy, and the general trend towards ecological development in twenty-first century china, bear some resemblance to ideas in europe and the usa, which have their origins in the nineteenth century, when scientists first began to use the term ecology. however, it should be born in mind that ideas that would now be included within the concept of ecology have been discussed for centuries around the world, and scholars in china and the west have been drawing on classical chinese thought for inspiration in thinking about contemporary environmental problems (egerton ; miller, yu and van de veer ). indeed, a concept of beautiful villages emerged in france in , culminating in the creation in of a formal organization entitled les plus beaux villages de la terre (the most beautiful villages in the world) to which villages in france, italy, québec and japan are signatories (lpbvt). however, there is no mention of international connections within the policy documents we analysed, and there is no sign that china wishes to join this international organization. moreover, there is no sign that officials in anji sought to engage with broader discussions on ecology, although they did acknowledge that the county had long emphasized the importance of its natural environment. officials also did not comment on whether previous state policies aimed at developing the countryside had been effective in shuangyi, or mention the new rural reconstruction movement, an intellectual campaign to develop the conutryside with roots in the s (day and schneider ). ideas and government policies can have many possible origins, and so it is important to trace the development of cbv in detail to understand how heritage can be part of a policy that is not designed specifically for this purpose. the concept of ecological development was first proposed in anji in . environmental protection was gradually incorporated into county policy, and anji was the first in china to be designated a county of ecological status by the central government in . this indicates not only how the central government recognises and rewards local initiatives, but also how far the concept of ecological development has taken hold in china as part of the policy to develop the new socialist countryside (marsden, yu and flynn , - , , ). in , two years after cbv was formulated by the anji government, the zhejiang provincial government announced that by , percent of counties should have implemented the policy (wang weixing , ). from then on, what became known as the anji pattern, grew in popularity. in november , at the eighteenth national congress, ‘beautiful village,’ became ‘beautiful china.’ this expanded the scope of the policy by applying it to cities as well as villages and by incorporating it into national policy, and therefore shifted the emphasis from the speed of the country’s development to its quality (liu linfang , - ). then, in at the nineteenth national congress, xi jinping again emphasized the importance of constructing a beautiful china, although this part of his speech focused on the environment, with heritage appearing in the discussion of socialist culture (xi jinping , , - ). meanwhile, cbv has been adopted in other provinces such as anhui, guangdong and jiangsu, and in the ministry of commerce announced billion yuan of funding, which was aimed at seven provinces to trial the policy. by the end of that year, , villages in counties were involved in the trial. in addition to this, provinces provided their own funding. anhui made billion yuan available per year, fujian invested million, and guizhou million (wang weixing , ). finally, in a further indication that cbv has support at the highest levels of government, it was one of clauses in the guanyu jiakuai tuijin shengtai wenming jianshe de yijianyi (concerning thoughts on increasing the pace of undertaking the construction of ecological civilization), which was released by the state council in may . while this focused on infrastructure development, improvement of agricultural methods, and reduction of pollution, environmental protection in general was important, as well as nurturing the culture and customs of villages, which help to create a civilized society (guowu yuan ). as mentioned above, cbv is part of the wider policy to develop the new socialist countryside (nsc), which was approved and written into the eleventh five year plan in . the nsc has its roots in rural reconstruction movements of the s and more recently the former campaign to construct a new socialist countryside under mao in the s and s, although given that policy’s link to among other things the disastrous great leap forward, the central government has been at pains to emphasize the twenty-first century iteration as something different. nsc aims to improve rural infrastructure and public services, such as education and healthcare, while also committing local officials to agricultural modernization, ecological sustainability, the creation of a civilized village life, and urbanization. despite these differences nsc bears the imprint of its maoist forebear. policy implementation is top down, with provincial or city governments setting out the guidelines, the county formulating a plan of implementation, and township and village cadres choosing which projects are eligible for funding. money is often distributed to those villages that aim to or have achieved model status, itself a legacy of earlier campaigns, the most famous being the village of dazhai, which was celebrated nationally throughout the cultural revolution as an example of efficient communist agricultural production. models allow for a policy to be first trialled, and then spread more broadly across the country. unsurprisingly, the injection of funds is an important motivating factor, even if villages have to find matching support. the success of individual projects within this policy is judged through the award of points. this could result in promotion for individual cadres and extra funds for those projects deemed to have been a success (perry , - ; schubert and ahlers , - , - ). the impact of nsc across china is undeniable. in many areas, it has resulted in real improvements, but the way in which the policy has been implemented has been overbearing and is reminiscent of former campaigns. first, propaganda teams spread the message, local officials undertake study programs, and often homes, lineage halls and other buildings are forcibly demolished to make way for new roads and housing (perry , - ). cbv certainly shares many of the same objectives as nsc. moreover, the process of evaluating its success depends on exactly the same top-down management and points system. however, this does not invalidate the motives behind the policy, nor some of the very real changes that have been experienced at village level. beyond this, the fact that it has several components means that in line with heilmann and perry’s thesis on adaptive governance, local officials can choose which aspects of the policy to emphasize, although all seek to channel money into infrastructure investment and to leverage local resources to increase rural income. these can include natural resources such as forests and lakes, local products, and tangible and intangible heritage (wang weixing , ; wu licai and wu kongfan , - ). adaptive governance in practice shuangyi underwent a number of changes that were directly linked to the financial incentives and policy guidelines within cbv. these ranged from physical changes such as turning the zhu ancestral hall into a museum, rehabilitating historic houses and re-inserting cobbled paths to subtler psychological changes such as seeing bamboo as intangible heritage, and proposing changing the name of the village to accord with its new status as a ‘beautiful village’. this section considers the practice of adaptive governance in the context of implementing the cbv policies. the focus is on how heritage is treated within the practice of adaptive governance and how this affects the physical transformation of the village. the negotiations between officials at different levels, and between village officials and residents, reveal the ways in which heritage was gradually seen as important within the context of rural change, and how the core cbv concept of ecology broadened to include heritage in order to obtain the necessary funds to stimulate socio-economic development. changing mindsets : value of heritage the pragmatism of the officials in seeing the opportunities that heritage could bring in the context of cbv was demonstrated by official a in stating before , i didn’t pay much attention to conservation. since beautiful villages, i started to attach importance to conservation. for beautiful villages, i needed to find the features and characteristics of our village. the features of shuangyi are bamboo culture and history. they can be utilised in various ways. this narrative was however couched within the broader discourse surrounding china’s turn to embrace their heritage. the cultural revolution and more recently the rapid pace of economic and social change had ‘disturbed and destroyed’ ‘historical resources’ and ensured that a ‘number of historical cities and villages vanished forever’ (official b). each interviewee expressed their view of the value of heritage, often through the lens of ‘loss’ if we lose our history, we lose ourselves. during the period of rapid development, we copied a lot of foreign culture. eventually we suddenly found out that we do not have our own cities. cities, streets and our daily life are the carriers of traditional chinese culture. this is our spiritual ballast (official b). we should know the process of our own history. if we lose all the ancient houses, there must be a disconnect within our culture. we are not talking about going back to the past. we are talking about the return of ideology, of architecture, of humanity. i think china can’t exist if there are no ancient houses (official d). in expressing these views, officials were consistent in their belief that villagers did not yet recognise the importance of heritage. as such, a dominant theme in the interviews was the perceived need of the officials to educate the villagers. this permeated each level of government as officials stated that ‘common people had not reached the stage that they would spontaneously protect historical remains’ as the villagers ‘did not keep pace with our consciousness’ (official b) or rather they ‘lack awareness and foresight. they are different from us’ (official a). that china, a one-party state, should have a top- down government controlled process of managing heritage is not surprising. this does not mean that there is no room for local interpretation, and no space for officials and the people to express their understanding of the past. indeed, a key hallmark of adaptive governance is the appearance of a dictatorial style implemented from above, but in reality, a style of governance that leaves local officials with sufficient flexibility to broadly interpret the policies. this flexibility allowed local officials on the one hand to use the villagers’ lack of knowledge as a way to legitimate their policies and on the other hand to draw on the villagers’ intimate knowledge of their history to help them meet the criteria for cbv. in reality, the process of adaptive governance was not a top-down education of villagers, but was rooted in a complex process of negotiation and pragmatism which had some contradictory consequences for the restoration and re-use of built heritage within the village. the tensions are highlighted most clearly in local attempts to meet the criteria for funding under cbv. as with other policies, which aim to create a new socialist countryside, cbv uses a points- based system in which funding is apportioned based on the number of points won. to achieve the status of premium model village, shuangyi had to obtain points out of a total of , (anjixian shengji shehuizhuyi xin nongcun jianshe shiyan shifanqu gongzuo lingdao xiaozu ). there were over criteria on which the village would be judged, the maximum income available was million yuan, and there was the possibility of applying for additional funds from the county development zone (official a). out of , points, heritage was mentioned in just , although various aspects of cultural improvement could also include protection and promotion of folk customs and handicrafts (anjixian shengji shehuizhuyi xin nongcun jianshe shiyan shifanqu gongzuo lingdao xiaozu ). the flexibility and manoeuvrability of adaptive governance was evident here in the physical manifestations of the cbv policy. for example, points were available if plans considered local characteristics and sought to use appropriate materials. within this, protection of old buildings and trees was worth one point, although their destruction could lose the village points. government officials thus developed a belief in the need to ‘restore the old as the old’ (official c), which was achieved with varying degrees of success within the village. firstly, the zhu ancestral hall and the historic cobbled paths were restored in line with this philosophy. the re-use of the zhu ancestral hall as a museum is one tangible outcome of the gradual development of heritage as a central part of cbv, the potential value of which was recognised by official a in . whilst many ancestral halls have been museumified, (svensson , - ) this was carried out to achieve the status of premium model village. now, adorning the walls of the zhu ancestral hall are exhibition boards that relate the village’s history, with cases displaying important documents, such as records of genealogies, and manuals on bamboo production. the exhibition projects the history of the village outwards, and is designed to showcase its uniqueness, its beauty, and the achievements of its people. it certainly displays the ahd by emphasizing the changes in the village under communist rule, especially since the beginning of the reform era, downplaying the impact of the great leap forward and the cultural revolution, and highlighting key figures such as party secretary zhu yuenian, who brought the village national recognition as a centre of bamboo production throughout the maoist era. figure : front of the restored zhu ancestral hall figure : interior of restored zhu ancestral hall, with display boards. in the opinion of the government officials the restoration of the zhu ancestral hall was catalytic through the conservation of the ancestral hall, we publicized the idea of conservation to villagers. it is impossible for villagers to spend their money to protect historical buildings voluntarily... as a result, once we have maintained the hall, villagers were willing to protect it out of a sense of history and family pride (official a). however, the process of ‘publicising the idea of conservation’ to the villagers was informed by members of the zhu family who worked with the design company to restore it to its pre- era condition which was deemed to be the ‘most impressive…architectural style’ (villager w). indeed, the officials’ assertion that they needed to ‘educate’ the villagers was contradicted by the villagers themselves, who stated that they had advised officials in that the ‘historical buildings of our village should be protected immediately’ (villager w). this account places the desire to conserve historic buildings two years prior to official a’s desire to conserve within the cbv guidelines, and demonstrates the disjuncture between events recalled by people in different positions of power. the protection of historic houses was, ostensibly, also top-down and often instituted without the knowledge of the villagers: ‘some of these houses are not qualified to be protected. in most cases we labelled the houses by ourselves. villagers don’t know, they think these houses are protected by the government’ (official d). following this, ideas about heritage were ‘promoted to the villagers’ who were also informed as to the benefits of conserving these houses (official e). these ideas were often put forward during formal meetings with the villagers in which they were asked to sign an agreement about how houses should be protected. it was stated that ‘we hold a meeting of village representatives. we promote and introduce our policies to them, then they sign [the agreement]’ (official c). however, the process of adaptive governance ensured that concessions were made by the officials with regards to the restoration and re-use of built heritage. for example, the use of concrete in the restoration of the historic buildings, whilst anathema to the requirements of elegance, was explained by villagers’ preferences and the problems with traditional materials: ‘villagers think cement lasts longer, and is stronger than wood. and rain would damage the mud wall’ (official a). however, on other occasions although the villagers believed walls ‘should be whitewashed’ and roads ‘hardened’ the management strategy was to ‘try to lead them using the beautiful villages construction’ (official a). figure : cement wall in front of late qing dynasty house restoring the historic cobbled paths proved to be even more contentious as the dichotomy between past and present was recognised by officials, who acknowledged that whilst the cobbles were ‘uncomfortable’ (official a), ‘impractical’ and ‘uneven’ (official d), returning the paths to their ancient state was, in line with the need to make the village elegant, a necessary requirement of it gaining the points to become a model village (official e). in reality the compromise position saw a confusing mix of styles and techniques, rather than the expressed desire to ‘restore old as old’ (official c). changing mindsets in terms of recognising the value of heritage was therefore key to the adoption of the cbv policies. however, this was not a one-way, top-down process of educating villagers. in fact, the tradition of adaptive governance saw the continual renegotiation of the value of heritage between officials and villagers. figure : restored cobbled paths and new paving around restored pond area in the centre of shuangyi village changing mindsets : reconceptualising heritage as ecology the process of changing mindsets was not just restricted to physical changes but also to the mental work of reconceptualising the nature of heritage within the context of cbv. cbv policies were primarily aimed at improving the ecology of villages, and the ability of officials to reconceptualise cultural heritage to fit within this context is a further example of adaptive governance. just how ecology is understood as the underlying ethos of cbv is set out in the initial proposal from anji in , and the zhejiang provincial plan that was published two years later. the policy documents contain three types of ‘ecology’: shengtai jingji (ecological economy); shengtai huangjing (ecological environment) and shengtai wenhua (ecological culture), with heritage having varying levels of importance in each of these areas. the ecological environment considers the environment in its broadest sense, and encompasses infrastructure such as roads, provision of clean water and sewage, and the control of pollution from agriculture, industry and housing. according to the provincial plan, by , each village and township should have one waste collection centre, hygienic toilets should be provided for percent of villagers, and sewage management should cover percent of the village. renewable energy, and energy saving measures such as the use of solar energy hot water heaters should be promoted. the natural environment surrounding villages, particularly forests, should be protected, and trees and other foliage should also be planted within villages themselves. finally, rural industry such as homestays for visiting tourists should not disrupt the natural environment (zhonggong zhejiangsheng wei bangongting ). although not a focus of the ecological environment, heritage has assumed importance in the rhetoric of government officials. this can be seen in three areas. firstly, government officials emphasised the symbiotic relationship between the natural environment and cultural heritage. they each expressed similar sentiments such as ‘an ecological environment is the foundation’ (official c) and that as such ‘ecological protection is slightly more significant than conservation’ (official d). however, it was also thought that a ‘good ecological environment benefits conservation’ and that ‘natural resources and cultural historical resources … will be protected at the same time’ (official b). this was attributed to spiritual values as both natural and cultural historical resources were seen as a ‘valuable treasure of human society which contribute both to social progress and the development of civilization’ (official b). in addition, it was believed that tourists would be more inclined to visit cultural heritage resources if the air was clean, the water free from pollution and the rubbish cleared. secondly, whilst the inextricable relationship between environmental ecology and heritage was highlighted by all officials, they also recognised that this had not always been the case. however, links were made between environmental protection, broadly defined, and heritage protection by highlighting their track record of protecting trees. shuangyi had ‘always been in the front of ecological protection’ and therefore the ‘tradition of protection’ could be extended from trees to built heritage (official d). this was further developed by the treatment of moral stelas, or stones inscribed with scripts: ‘we have moral stelas which detail ecological protection, among which the oldest were set up in the song ( - ) and yuan ( - ) dynasties. ecology is an organic component of our culture, and a part of our historical inheritance’ (official c). in these ways ecological protection was seen as synonymous with cultural heritage protection, while also being something that was historically embedded in the locality. thirdly, drawing a connection between the built and natural environment was a key theme within the interviews as officials discussed built heritage as ‘ecological architecture’ (official c). this was justified in terms of the environmental sustainability of the historic houses as they were considered to have ‘advantages like retaining warmth, excellent ventilation and natural lighting’ (official c). in addition, restoring tangible heritage had the added benefit of ensuring the intangible craft skills of traditional building methods could be applied to modern construction. environmental ecology was thus broadly defined to ensure that both tangible and intangible heritage could become a key part of justifying applications for government funding, and so ensuring the socio-economic and environmental development of shuangyi under the cbv policy. cultural heritage was also reconceptualised to fit within the broad definitions of an ecological economy. this form of economy seeks to increase rural income through supporting agriculture and other activities such as tourism, but not at a cost to the environment. here the bamboo industry, traditionally a pivotal part of the shuangyi economy, was reconceptualised as heritage. more specifically, the production of bamboo was seen as intangible heritage, the products of which could be sold to a burgeoning tourist market. however, the plans also stated that the development of the ecological economy should focus on creating a new industry in the form of homestays, which should be linked closely to the protection and promotion of the natural environment. attracting domestic tourists from within china was central to the longer-term development of shuangyi. in order to achieve this, officials discussed the need to attract private investment and cited several examples including an entrepreneur, who ‘tried to keep some old buildings in his hometown by running cultural and creative industries, and restaurant and entertainment service industries inside those old buildings’ (official b). this form of development was considered to be ‘immature’ but in the future, it was perceived to be a ‘new approach of conservation’ (official b). this was further developed by using examples from songyang county where traditional villages were given ‘ million yuan last year’ ( ) as a result of their designated status (official a). the potential for shuangyi to attract public and private investment to further its development was clearly tied to a re-appreciation of the historic value of both its tangible and intangible heritage. government officials also noted the potential for heritage to become a central part of the ecological economy as they recognised that ‘value comes from scarcity’ and as such the ‘feature of shuangyi is history and culture’ (official a). this economic potential was partly connected to the potential for improvement in the external reputation of shuangyi that officials believed was possible if the village was seen to emphasise its heritage. for example, officials believed that the ‘ancient houses and paths…contribute to our taste and style’ (official a). this was supported by all levels of government as officials stated they believed that zhejiang was an exemplar, while for example, ‘jiangxi province is a decade behind zhejiang in this project’ whereas other officials emphasised how ‘in , anji was the first and the only one that won the “united nation habitat award” as a county’ (official c). the role of heritage within the ecological economy was therefore crucial to improving the reputation of anji county as a leader in ecological protection. the increased role for heritage within the ecological economy was perhaps best exemplified by the desire to change the name of the village to phoenix historic village as shuangyi was deemed to be ‘unattractive’ (official d). furthermore, using bamboo to market the village was an integral element of this rebranding as the slogan ‘bamboo king of china’ was seen along with phoenix historic village as ‘our development strategies’ (official d). in , the village formed the shuangyi bamboo share co- op in partnership with a tourist company in hangzhou. its goal was to develop tourism, including homestays, scenic tours of the village and its surrounding area, and to help market local handicrafts. beyond this, at the beginning of , a businessman invested million yuan in the village, and at least one villager opened a homestay business. the importance of preserving the intangible heritage of bamboo protection was a central element of shuangyi’s interpretation of cbv. these economic development strategies were again tied to a recognition of the village’s history, since the ‘honour of shuangyi’ rested with ‘bamboo culture’ (official d). in these examples, the reconceptualisation of heritage to include both tangible and intangible forms was used to meet the needs of cbv. the definition of an ‘ecological culture’ within the zhejiang plan of stated that the specific characteristics of each village should be developed, protected, and enhanced. it is here that there are more explicit references to heritage. protection and preservation of culture is seen as paramount, and the provincial plan emphasizes ‘the preservation of ancient villages, ancient public buildings, ancient architecture, old trees and wood, and folk culture and other cultural heritage’ (zhonggong zhejiangsheng wei bangongting ). the county document highlights the importance of rural lineages, which as the zhu ancestral hall shows are key to a village’s heritage and identity, although it also discusses education, sport, provision of facilities for old people, and explicitly links culture with tourism and economic activity (zhonggong anjixianwei bangongshi ). both documents argue that the level of village culture needs to be raised, a tone that as we saw above, was also adopted by government officials in their desire to educate villagers as to the value of heritage. these definitions were aligned with the pursuit of shuangyi as an ‘ecological civilization model’ (official d). this model emphasised both intangible heritage through protecting traditional handicrafts as well as tangible heritage through the restoration and re-use of historic houses within shuangyi. again, the concept of ecology was multi-layered with environment, economy and culture mixed together as demonstrated by the example of giving each family ‘three bamboo baskets’ to convince them ‘to stop using plastic bags’ which in turn ‘protect the craftsmanship of bamboo wares’ which can be sold to tourists (official d). within the ecological civilisation model, it was stated that ‘we lead villagers to know what is forbidden and lead them to take part in conservation’ (official d). this aligns with the view that villagers needed to be taught the importance of their history. recognising the importance of selectively conserving the history of shuangyi was considered a crucial element of the ecological culture. this model also couched the key characteristics of the village in a fluid and plural definition of ecology, which in turn reconceptualised intangible and tangible heritage to align with that more inclusive notion of ecology. conclusion the evolving use of heritage within cbv demonstrates how government officials at different levels are able to mobilize resources to protect and adapt it within a policy environment that is designed to govern rural development as a whole. despite the fact that heritage, in one form or another, is mentioned in just of the points available for cbv the desire to improve the ecology of the countryside was seized upon by local officials who skilfully manoeuvred through the various points- based systems, negotiated with villagers, and reconceptualised heritage to fit with the requirements of various policies and agendas. at each stage officials recognised and reconceptualised selected elements of shuangyi’s past to satisfy the broad agenda of cbv. they achieved this through the tradition of adaptive governance in china, most notably through the significant levels of local autonomy present in the system of rural governance. however, the result of this governmental dexterity was a rather odd mishmash of conservation styles within the village, in which modern materials such as cement are seen as an acceptable way of preserving traditional ‘ecological’ architecture. rather than locate these rather contradictory approaches within the supposed dichotomy between the philosophies of heritage conservation in the east and west we argue that an analysis of the practice of adaptive governance engages with winter’s call for ‘fine-grained understandings of regional, cultural, religious and local variations in conservation practice’ ( , ). whilst china, and indeed asia more generally, may be less ‘material centric’ ( , ) and therefore it is more acceptable to use modern materials, this judgement hides the rich complexity of negotiation, pragmatism, and flexibility within the decision-making processes in operation at the local level. the case of shuangyi demonstrates the need to focus on the ways in which ideas about heritage play out within the reality of policy formation. the reconceptualisation of heritage as ecology concerns ingrained beliefs about the ‘inextricable’ relationship between ‘the physical, human-made components of the heritage’ and the ‘natural geography and environmental setting of their respective cultures’ (hoi an protocols for best conservation practice in asia , ) and the need for local officials to use the past to stimulate socio- economic development. as oakes has argued ( ; ) heritage conservation within rural areas is seen as a practice of ‘improvement’ and integral to ‘modernization and development’ ( , ). oakes takes this one step further to state that to ‘baohu (preserve) something in rural china these days is not so much to “preserve” it, but to prepare it for development, to turn it into a visitable attraction’ ( , ). furthermore, alongside perceived economic gains is political prestige, given that there is a direct relationship between economic growth and an official’s place on the political ladder (zhang and gao ). changing mindsets in shuangyi was therefore the product of a complex entanglement of politics, economics, culture, and the environment wrapped up in the container of cbv. in this context, it is not surprising that what can be considered to be heritage is continually subject to ‘interpretation and reinterpretation, claim and counter claim, and negotiation’ (harrison , ). mobilising heritage was a key element of the implementation of the cbv policy in shuangyi, and it was couched within a unanimous belief from the officials that their plans could only work if villagers could also recognise the value of their heritage. this educative process was not solely a top- down imposition of ideas onto the villagers but rather a continual process of negotiation in which some concessions were made and others are still to be resolved. while the ccp is no-longer as overbearing as it was during the maoist era, and particularly during the cultural revolution, it has more power to define the space in which officials and people have the freedom to operate than is the case in countries with more pluralist political systems. however, an often surprising amount of local autonomy allows people to engage with their past. moreover, as with governments around the world, there is a messiness to policy making and implementation, out of which instrumental value derives. in china, this is because of the tradition of adaptive governance. in the case of cbv, this gives heritage an instrumental value, which subordinates it to other developmental priorities in the countryside, but nevertheless gives local officials the opportunity to mobilize their heritage in the name of ecology, and so gain resources for its protection. in china then, as elsewhere, it is in the messiness of politics at the local level that the complex negotiations between people, officials and legislation, play out. it is out of this continual process of negotiation that the different values of heritage are ultimately determined, only to be re- worked again with each new generation, policy shift, or change in government personnel. at present, the notion of a beautiful china creates space for heritage protection, and although it may eventually be supplanted, it currently has xi jinping’s support, and so there is the chance that much rural heritage in china may be protected under this policy. references anji dipuzhen shuangyi cun 安吉递铺镇双一村 [anji dipu town shuangyi village]. . chuangjian zhejiang sheng lishi wenhua cunluo sheji 创建浙江省历史文化村落设计 [plan for the organization of a historical cultural village in zhejiang]. anjixian shengji shehuizhuyi xin nongcun jianshe shiyan shifanqu gongzuo lingdao xiaozu 安吉县省级社会主义新农村建设实验示范区工作领导小组 [anji county provincial level socialist new countryside construction experimental model area work leadership small group]. . guanyu yinfa <> de tongzhi 关于印发 <<安吉县 “中国美丽乡村” 精品示范村考核验收暂行办法 >> 的通知 [concerning the announcement on the publication of provisional methods for inspecting the <>]. caizheng bu 财政部 [ministry of commerce]. october . yishi yiyi caizheng jiang bu tuidong meili xiangcun jianshe shedian 一事一议财政奖补推动美丽乡村建设设点 [case by case ministry of commerce prizes to support the promotion of pilot projects to construct beautiful villages]. http://www.gov.cn/gzdt/ - / /content_ .htm. “guowuyuan guanyu jiakuai tuijin shengtai wenming jianshe de yijian.” 国务院关于加快推进生态文明建设的意见 [state council concerning some opinions on increasing the pace of promoting the construction of ecological civilization.] xinhuashe 新华社 [xinhua news] april . http://news.xinhuanet.com/politics/ - / /c_ .htm. day, alexander f., 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http://news.xinhuanet.com/english/special/ - / /c_ .htm soil lacquer peel diy: simply capturing beauty cathelijne r. stoof , jasper h.j. candel , laszlo van der wal , gert peek soil geography and landscape group, wageningen university, po box , aa wageningen, the netherlands correspondence to: cathelijne r. stoof (cathelijne.stoof@wur.nl) abstract. visualization can greatly benefit understanding of concepts and processes, which in soil science and geology can be done using real life snapshots of soils and sediments in lacquer peels and glue peels. while it may seem complicated, anyone can make such a soil peel for use in classrooms, public places, homes and offices for teaching, outreach, decoration and awareness. technological development has considerably simplified the making of soil peels, but this methodological innovation has not been described in the literature. here, we report on a thoroughly tested and simple method for taking peels of sandy soils using readily available tools and materials. our method follows the main previously published steps of preparing a soil face, impregnating the soil face with a fixation agent in the field, extracting the resulting peel and mounting it on a wooden panel. yet instead of using lacquers and thinning agents, we use strong though flexible contact adhesive (glue), which has the major advantage that it no longer requires use and mixing of toxic chemicals in the field or reinforcement of the peel to prevent breaking. moreover, the preservation potential is much higher than with the old method. this new twist to old methods makes creating of soil peels more safe, simple and successful, and a thereby true diy (do it yourself) activity. the resulting increased accessibility of making soil and sediment peels can benefit research, teaching, and science communication and can thereby bring the value and beauty of the ground below our feet to students, schools, policy makers, and the general public. introduction attention for soils is increasing around the world, in part due to strong initiatives on soil health (stott and moebius-clune, ;schindelbeck et al., ) and soil carbon ( ‰, minasny et al., ), and explicit articulation of how soils can help achieve the united nations sustainable development goals (keesstra et al., ;bouma and montanarella, ). the relevance of soils lies in the valuable beauty of soils: their multidisciplinary functions and benefits (brevik et al., ;dominati et al., ) and thereby their basis for life, in a world where soils are under threat (montanarella et al., ). capturing this beauty in monoliths or soil lacquer peels can bring soils to life for education and outreach (van baren and sombroek, ;lawrie and enman, ) or as a form of art (feller et al., ;breaker, ). while it is often thought to be quite challenging to capture soils, a simple twist to an old method now makes the creation of soil peels a surprisingly simple do-it-yourself (diy) activity for scientists, educators and the general public. soils and sediments can be fixated in two distinct ways: using peels and monoliths. both methods rely on impregnation of a soil face with a fixation agent (such as lacquer, resin, or glue), and their final product is typically mounted on a wall for study soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. of undisturbed soil layers and characteristics, or simply for decoration. peels and monoliths are used to record and illustrate a range of different features in soils, such as differences between soil types, soil processes (e.g. weathering, gley, eluviation and illuviation of clay, iron, and organic acids (fig. a)), human impacts (fig. b) as well as biological activity such as plant rooting patterns, burrowing of soil fauna, and bioturbation. sedimentological and geological processes can also be captured, such as cryoturbation, fluvial and aeolian layering (fig. c), frost wedges (fig. d), and faults (fig. e). and finally, peels can show the splendid colours present in soils and sediments (fig. a-f). these natural snapshots of the subsurface are an effective way to inspire people about soils (megonigal et al., a) and geology, and are used around the world by museums, universities, schools and institutes (table ) for teaching and outreach on the value of soils, the processes occurring in soils, effects of management, and other factors. interestingly, these soil profiles are also used for testing knowledge of soils in job interviews (personal communication, jacqueline hannam). peels and monoliths allow comparison of soils inside a classroom or museum environment without the need for students or visitors to travel to see a variety of soils. consequently, soil science education at wageningen university, the netherlands, strongly relies on a collection of ~ lacquer peels for teaching purposes – despite the fact that this university is intentionally strategically located in an area where soil variability is high (van der haar et al., ) due to the range of distinct parent materials (glacial, peri-glacial, fluvial, aeolian, organic) and topography, and thus soil types within a -km radius of the university. the main difference between making peels and monoliths is the location where the soil is impregnated: a peel is impregnated in situ and extracted after drying, while a monolith is an undisturbed soil block that is extracted, transported, and then (repeatedly) impregnated in a laboratory (van baren and sombroek, ). monoliths can be created in any soil type, from sands to peats and heavy clays, but is rather time consuming and requires specialized expertise both in the field and in the laboratory. their creation and recent methodological developments are rather well described in scientific journals (e.g. bouma, ;haddad et al., ;allaire and bochove, ;wessel et al., ;wright, ;donaldson and beck, ;barahona and iriarte, ;fitzpatrick et al., ), presentations (fosberg, n.d.) and reports (e.g. van baren and bomer, ;kiniry and neitsch, n.d.;day, ;schuurman, ), as well as illustrated in online videos and tutorials (e.g. university of nebraska - lincoln, ;mueller, ). in contrast to soil monoliths, soil peels cannot be made from clay or peat soils since these are often too wet for impregnation in the field. peels are therefore limited to relatively coarse sediments that retain less water (lower water holding capacity) and allow more rapid impregnation of fixation agents (because of their higher hydraulic conductivity) which is required in field situations. they thereby provide a rapid and accessible alternative to soil monoliths. the lack-film method for creating peels was first developed in the ’s (hähnel, ;voigt, ;jahn, ). yet while the use of soil lacquer peels for scientific purposes has been recognized, e.g. to study sedimentological structures (bijkerk et al., ;van den berg et al., ), for palaeo-geochemical analysis (arnoldussen and van os, ) or archaeological applications (voigt and gittins, ), the guidance available in the scientific literature is scattered, (out)dated and/or incomplete. an english book that stands out is the comprehensive work by bouma ( ) that details the history of soil and sediment peels as well as a range of fixation agents used to make these peels. other published work includes a range of dutch and german-language papers, popular-scientific articles and reports (vos et al., ;huisman, ;tno, ;van veen, soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. ;hähnel, ;voigt, ), as well as a few older english-language articles (voigt and gittins, ;van baren and bomer, ;brown, ;hähnel, ). these publications describe a range of materials used to make peels, most notably (nitrocellulose) lacquers but also glue and resin. the main steps of the published methods for making peels are straightforward: a soil face was prepared under an angle and then (repeatedly) impregnated with a fixation agent, with the peel extracted after drying and then mounted on a wooden board. the challenge of the published methods lies in the fixation agents used years ago that required use of toxic solvents (e.g. acetone, toluene, xylene, thinner; bouma, ) in the field to achieve the right viscosity, increasing the risk of harming people and the environment. the resulting peel was rather fragile, hence reinforcement with cheesecloth or bandage was required to prevent rupture of the dried lacquer peel (bouma, ). this fragility results in a lower preservation potential, which we have noted was especially challenging when the soil peels were frequently used for teaching. here we describe and illustrate a more simple, safe, and durable and thereby more accessible approach of making soil lacquer peels, which relies on the use of glue available at hardware stores. while still synthetic, this glue is less harmful than the fixation agents, and its use straight out of the can reduces spilling risk associated with the mixing of chemicals in the field. finally, this method invariably yields excellent results also when used by those who have received no training. this new twist to an old method was developed by gert peek, a soil science educator at wageningen university who started teaching at what was then the laboratory for soil science and geology at the landbouwhogeschool wageningen. as such, this method was used to collect both teaching material and data for msc theses (e.g. van der beek and ellenkamp, ), and to enthuse hundreds of students to get a podzol above their bed, through the organization of ‘soil profile weekends’. as we believe it is essential that scientific methods are preserved for future generations, we now report the simple steps to capture the beauty of sandy soils for use in universities, schools, government buildings, museums, or simply at home. taking the soil peel: six main steps . collect the required materials materials needed. a range of materials is required to make a soil peel that can typically be found in any hardware store. table lists all materials required to prepare the soil face (a spade, pruning scissors or garden shears, nail clippers, soil knife, ruler), to secure the soil (glue), to extract the peel (wooden board, spade, soil knife, pruning scissors or garden shears, garbage bag), finish the lacquer peel (glue, notched trowel, stanley knife, nail clippers, scissors), and mount it (hooks). in terms of personal gear, garden gloves and clothes that can get dirty are sufficient. any size can be chosen for the final size of the soil peel, and thus the size of the wooden board. soil profiles at wageningen university are typically × cm. a wooden panel > mm thick (to prevent warping) is used for mounting - we use multiplex or mdf though any wood can be chosen, depending on desired aesthetics. characteristics of the glue. the fixation agent used to impregnate the soil face is a liquid contact adhesive based on neoprene rubber. originally designed for shoe repairs that requires two sides to be pressed together, this neoprene rubber contact soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. adhesive works very well for making peels because it is flexible yet strong when dry. this flexibility is key for successful extraction of the peel from the soil face: glue that fully hardens when dry (like wood glue or glues used to impregnate monoliths in the lab) will break upon extraction and/or mounting of the peel. another benefit of this glue is that it does not shrink when drying, unlike the lacquer used for instance by (hähnel, ). in the netherlands, neoprene rubber contact adhesive is sold as bisonkit universal (bolton adhesives, rotterdam, the netherlands (bison international, b)), which is internationally sold by the same manufacturer under the brand names uhu kontakt kleber and griffon contact. the yellowish brown color this glue does not affect the colour of the final peel. neoprene rubber contact adhesive is also known as polychloroprene glue, contact cement, or contact adhesive, and is elsewhere sold by manufacturers such as m, dap weldwood, pliobond and k- flex-usa - check the suitability of these products in the field before purchasing large volumes. because some of these brands still contain toluene, it is also advisable to request (material) safety data sheets (known as (m)sds in the usa) to check for any required personal protective equipment. the volume of glue (vg [l]) required to make a peel, including excess edges and mounting the peel, is calculated as equations and : vg = . × (bw + . ) × (bl + . ) + vm eq. vm = . x bwbl eq. where bw [m] and bl [m] are the width and length of the wooden board and thus the final size of the peel, respectively, and vm [l] is the volume of glue needed to mount the peel to the wooden board. for a final peel size of × cm, l is sufficient. at a cost of - € per l, the total costs of a typical profile amount to under €. as many stores allow return of unopened cans of glue, we typically purchase more glue than we need and return the excess. . general preparation find a good location. in the old days (up to the ’s) when workload at universities was still low, the frequent and lengthy soil mapping field courses allowed for many opportunities to find beautiful soils and capture them in peels. finding a good location can just be a factor of being outside a lot, knowing the surroundings, and scraping off the outer few centimeters of an exposed road cut to reveal the original soil underneath. alternatively, with less time spent outside, good locations can also be found using digital maps that are often available online. whether outside or behind a computer, four main factors determine the suitability of a location for making a soil peel: ) soil texture, ) groundwater depth, ) a natural or man-made elevation difference, and ) accessibility (fig. a). first, regarding soil texture, lacquer peels are best made in unconsolidated sandy deposits (such as commonly found in delta areas) with low clay, silt and organic content and ideally low rock fragment or gravel content. clay and silt have low permeability (rawls et al., ) and so does organic matter when compacted (ohu et al., ), and thereby result in very soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. shallow impregnation of the glue, causing potentially fragile layers. based on years of field experience making soil peels we found that the textural classes “sand” and “loamy sand” (soil science division staff, ) are best suitable. this indicates that the clay + silt content should not exceed %, with a maximum of % clay. the minimum sand content should therefore be %. at the same time, the organic matter content should not exceed ~ % (humic conditions, sensu de bakker and schelling, ). rock fragments and gravel are challenging to work with because they affect the smooth preparation of the soil face (section . ) and additionally may fall off the final peel (section . ), although results can still be quite successful. to find locations with suitable soil texture and organic matter content, the s-world model (stoorvogel et al., ) and the soilgrids tool (isric, b;batjes, ) are both valuable and free resources. second, groundwater depth is important because results are best if soils are dry, since the glue used does not adhere properly when soils are wet. groundwater level variation can be part of hydrological monitoring setups, but also be recorded on soil maps as average highest and lowest groundwater levels (e.g. bis nederland, ). given that warm and dry weather in late spring or summer are often most beneficial for making soil peels, the most relevant groundwater information there is the average lowest groundwater level (which occurs in summer). the global map of groundwater table depths created by fan et al. ( ), albeit coarse, can give a first indication of whether a region may be suitable for making soil peels. subsequent combination of soil texture, organic matter, and groundwater information can then provide insight into where peels can be made (e.g. fig. ). combined with information about capillary rise (~ . cm in gravel to > m in silt; singhal and gupta, ), locations of suitable dryness can be found, which is in soils and sediments above the capillary fringe. third, an elevation difference is essential when making lacquer peels of vertical cross sections of soil or sediment. this elevation difference can be created by digging a soil pit, which can be done by hand. approximately m is needed to have sufficient work space, with a . - . m depth of the pit to obtain a . - . m long peel. however, as digging a pit can be time consuming, the most ideal places to make peels are natural drops in elevation such as eroded river banks, or man-made cases such as road cuts, quarries, construction works (river restoration, cable installation), or archaeological digs. contact local authorities or companies to ask for temporary opportunities, or consult elevation maps for more permanent locations. elevation maps are often available online. digital elevation models (dem) may also be used, for example the ahn (actueel hoogtebestand nederland) in the netherlands is a freely available elevation map with a resolution of . by . m (van heerd and van’t zand, ). international examples include the eu-dem with a resolution of by m (eea, ). arrange permission. locate the landowner and ask their permission. as many non-soil scientists do not know what a lacquer peel is, a simple explanation free of scientific jargon is to refer to it as a ‘soil painting’ or ‘soil art’. be honest about the use of glue, but also explain that you will clean everything up. check whether the landowner would like to receive notice about the exact moment the fieldwork is planned – though as the process of making a soil peel is weather-dependent, this can often not be indicated much in advance. get the timing right. in some climates, planning ahead for making lacquer peels can be challenging as this activity is rather weather dependent. results are best when soils are dry, creating more intense colours and higher contrast of colours in the peel. in the netherlands, our experience with the ‘soil profile weekends’ learned that two weeks of dry weather in late spring soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. or summer is sufficient to achieve good results. we have never had issues with soils that were too dry, and with the materials we use there is no need to spray the soil with water as suggested by bouma ( ). while it is possible to make a peel when the soil is moist, the result is not as beautiful because of reduced appearance of for instance podzol fibers, or simply because the glue will not adhere to the sand. note that while soil moisture contents may strongly vary in time, there may also be considerable differences within a soil profile. when sand may be already dry, horizons with more organic matter or clay can still be quite moist because of their strong effect on soil water retention (rawls et al., ;wösten et al., ). these within- profile differences may be exacerbated by impermeable layers: we once encountered major issues when extracting a peel from a podzol that had a perched water table due to an impermeable bh horizon. while application of the glue (section . ) was successful, the extracted peel showed that the glue had not adhered to the very wet e horizon above the bh, while the c horizon below the impermeable layer was dry and adhered just fine. this peel was later restored in the lab (section . ) using dried sand collected from the e horizon. dry weather is recommended both in the couple of weeks before making a peel as well as during the two days in the field (section . - . ), when also air temperature is important. follow manufacturer’s recommendations regarding the temperature at which the glue can be used (e.g. - °c, bison international, a). particularly the first hours after impregnation are critical because any rain occurring soon after impregnation (within - h) may create bubbles in the glue, resulting in poor impregnation and therefore ‘bold’ spots with reduced sand cover upon extraction. high relative humidity can potentially have similar effects (e.g. > %, bison international, a), although we have never had such issues in the field. . field preparation: prepare soil face and cut all roots prepare soil face. use a spade to make a straight soil face at a ° (loamy sand) to ° (sand) angle (fig. b). the dimensions of the soil face to be impregnated should be somewhat larger than the intended size of the lacquer peel. make the soil face cm wider than the final peel on either side (fig. b), because it is never fully predictable how the glue will flow and thus what the final surface is that will be covered. also, extend it - cm below the bottom end of the intended peel to allow unimpeded flow. an additional benefit of making the soil face larger than the final size of the peel is that it allows selection of the best or most beautiful part of the profile for mounting. after all, the final appearance of the front of the lacquer peel remains hidden until after excavation, as the lacquer peel is a mirror image of the soil face. it is therefore always a surprise what the final peel will look like, which is why having additional space to choose the most beautiful part for installation on the board is useful. the prepared soil face should be as smooth and straight as possible – any bumps and hollows can hamper smooth distribution of the glue in the next step. perfection is not possible though, especially when sediments are brittle or gravelly. it would not be the first time that removing ‘one last thing’ can cause collapse of part of the soil face and thereby necessitate much larger restoration work before the glue can be applied. trim roots and remove rock fragments. cut away all roots protruding from the soil face using garden or nail clippers (for large and small roots, respectively) and remove any rocks or large rock fragments (fig. c). roots or rocks that stick out will retain glue and can thereby create glue-less pockets that will appear as holes in the finished lacquer peel. cut the roots as close to the soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. soil face as possible while avoiding any dislocation of sand grains. this can be a rather tedious process as the number of roots can be surprisingly high. yet careful removal of roots and rock fragments will allow smoother impregnation of the soil face (step ), easier mounting of the peel on the wooden board (step ), and thus better final results. make ledge. create a -cm ledge above the soil face (fig. c), providing a place to pour the glue, and preventing any soil material from above from falling on the profile. if the top of the soil face is the same as the mineral soil surface this ledge can be created by removing any litter and vegetation. if the top of the soil face starts mid-way a slope, this ledge can be made by simply cutting cm into the soil. install gutter. position a gutter underneath the soil face that can collect any excess glue (fig. c). a piece of pvc pipe (diameter - cm) sliced in two and then capped on both ends can function as a good gutter, although a plastic bag may also do if positioned well. if the firmness of the soil profile allows, cut a -cm overhang below its bottom and locate the gutter underneath this overhang. the total time required for field preparation strongly varies with the degree of care taken when preparing the soil face – a general time estimate for this step is ~ h for soils with a good rooting pattern. in sediments with no roots this step can be done in - min. . impregnation: securing the sand grains with glue apply the glue. to allow for rapid application of the glue, open all the cans of glue and place them within reach of the soil face – or close to a helping hand who can give the cans to the person applying the glue. in contrast to the previously discussed older methods that required on-site mixing of glues or lacquers with thinning chemicals, glues used here are ready-for-use and can thus be used straight out of the can. application of the glue on the soil face is easiest when using wide-mouth cans (~ cm diameter); we recommend using an empty vegetable can for pouring if the glue container has a more narrow opening. gently pour the glue by starting at the top ledge and moving the can across the width of the profile in a zig-zag pattern (fig. d). while the glue moves downwards also move down the location where the glue is applied. most likely, a finger-like pattern will appear in the glue (fig. d, video ), especially when the soil face is rather vertical. this preferential flow is caused by the fact that liquids have a strong tendency to follow existing zones of (even slightly) higher liquid content (liu et al., ), because of the large differences in hydraulic conductivity and thus flow velocity in dry and wet materials. fill in the gaps between the preferential flow paths by pouring glue at their top and continue this process until the glue has reached the bottom of the soil face. when the bottom of the profile is reached, the impregnation stage is finished. we recommend application of only a single layer of glue: we qualitatively tested the effect of adding additional layers of glue, which did not improve the final product. in one case, application of a second layer of glue even resulted in movement of the initial layer, creating a glue- less patch and thus a hole in the final peel. clean up. with the glue application done, the impregnation step of making the lacquer peel is finished. the neoprene rubber contact adhesive is so strong and yet flexible within the first days of application that it can easily hold the weight of a soil profile without tearing. as such, reinforcement of the peel with cheesecloth as directed by bouma ( ) is not required. soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. collect any excess glue that is still liquid from the top ledge and the bottom gutter. remove all trash and leave the site such that any visitors (people or animals) cannot harm themselves. cover the impregnated soil face with a large (fisherman’s) umbrella if there is a chance of light rain, and wait - h to let the glue dry (fig. e). the exact drying time will depend on meteorological conditions (air temperature, relative humidity, and wind) and exposure of the profile. it may be that the profile is dry and ready for extraction after less than - h. testing of potentially reduced drying times in different conditions is advisable in cases where time is tight and weather conditions are advantageous. . extracting the peel clear sides. extraction of the peel from the soil face involves the repositioning of a lot of loose sand from behind the peel to the sides. to facilitate this sand removal, make sure that the soil face on either side of the impregnated section is flush with the lacquer peel for a width of ~ cm on either side. it is also advisable to remove sand around the bottom of the profile. cut out peel from above. everything is now in place to start digging out the peel from above using the serrated edge of a (soil) knife. starting at the top ledge, use the (soil) knife like a saw to make a cut - cm away from the glued soil face across the entire length of the peel (fig. f, video ). the knife cuts fine roots; use garden clippers to cut off larger roots ~ - cm away from the glue. the further out from the glue you make these cuts, the longer the roots will be that stick out of the finished peel, which can always be trimmed in step . extraction of the soil peel is best done with two people, and can be done from the top (as outlined here) or from below (as outlined by bouma ( )). to extract the peel from the top, one person cuts away the soil and moves loose sand away from behind the profile and works their way down the profile. once the top of the lacquer peel has been freed, a second person then presses a wooden board against the soil face and holds the top of the profile against the board (fig. f, video ). this is to support the peel and prevent any tearing along fragile layers such as podzol fibers or thin loam bands. if the peel is heavy, for instance in the case of very structured soil, it can be partly folded over the top of the wooden board. covering the edge of the wooden board with a thick towel can then reduce the risk of tearing that can occur in fragile layers. digging out the lacquer peel can be easy and straightforward if the peel is small and does not contain roots or concretions. very small profiles (e.g. by cm) can even be done by a single person. extracting a more typically sized peel (e.g. cm wide by cm long) is not necessarily difficult but it can be arduous if layers are densely rooted or structured. still, to minutes is usually sufficient to remove peels from a soil face. . mounting the peel choose your mounting location. the extracted soil peel can be mounted on a wooden board either directly in the field, or after transporting the peel to a laboratory, shed, carport or garage. mounting the peel in the field allows for safer transport, yet it does typically mean that the size of the wooden board and thus the final size of the lacquer peel is predetermined – unless there is a possibility to bring power tools to the field to trim a board to size. using a fixed board size is not a problem when making soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. soil peels for teaching or outreach collection, but when using peels for soil art it can be worthwhile to determine the final peel size after extraction. after all, since the peel is a mirror image of the soil face (as discussed in step ), its final appearance remains a surprise until it is extracted from its location. test positioning. when ready to mount the peel, test its position on the wooden board to decide which features to keep. measuring how much the peel will extend beyond the sides of the wooden board helps exact positioning once the board is glued. if the peel is too heavy to lift, reduce its weight by remove large aggregates by hand, and/or by very carefully removing any large clumps soil with a soft brush. a brush may also be used to remove loose sand (always stroke sand away in the direction of any soil layering) but only if the glue is fully dry. glue the wooden board. cover the wooden board with some of the remaining glue (fig. g), making sure to particularly cover its sides and corners as these are the most vulnerable parts of the finished peel. use of a notched trowel facilitates an even spread of the glue, while corners and sides can be reached by hand using household gloves. work swiftly as the glue dries quickly, particularly when weather is warm (> °c) and windy. attach peel to board. lift the lacquer peel up with two people and place it on the wooden board directly in the desired location: as the glue will create an instant grip, changing the alignment of the lacquer peel will be very challenging if not impossible. press peel in place. carefully but firmly press the lacquer peel to the wooden board with your fingers. again pay particular attention to the sides and corners of the wooden board to secure these well. remove loose sand. turn the peel on its side and release any loose sand still resting on the peel by manually knocking the back of the wooden panel. repeat until no sand falls off anymore. keep some excess material from each layer (soil, any rock fragments, large roots) to restore any damaged patches later if needed. trim peel to size. now that the peel has been secured to the wooden panel, trim it using a sharp (stanley) knife (fig. g). with one side of the knife touching the side of the wood, cut off all parts of the soil peel that extend beyond the wooden board. restore any damaged patches and trim roots (if desired). in some cases peels may have small holes or damaged patches if glue distribution was not uniform or where rock fragments or larger roots have fallen off. these patches can be easily restored by applying some glue and covering it with the appropriate material for that layer, such as soil particles, a rock fragment, or a large root. this is also the moment where roots can be trimmed if desired using shears or nail clippers. there is no predetermined root length, the final root length is very much part of the artistic freedom and the message that is communicated with the soil peel, if any. . finishing, installation and maintenance ventilate. the soil peel now requires some rest in a well ventilated place to let the glue fully solidify – we ventilate our profiles for a minimum of days. as glue fumes can be rather intense, a garage, shed, or covered dry outdoor location is best for this. make sure to place the lacquer peel in a horizontal position – placing it vertically shortly after mounting may result in vertical movement of the drying glue, and thus distortion of the soil profile. soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. finish. many authors suggest impregnating the undisturbed front of lacquer peels (e.g. huisman, ;tno, ) to intensify the colours of the soil particles and secure any loose particles. our team has done that from to using a large can of the cheapest hairspray sold at the local drugstore, applying it one week after the soil peels were mounted. the hairspray did bring out the colours more, but once surprisingly produced such dark colours that any colour variation in the peel was obscured. it may be that the formula of the hairspray had changed, but the exact reason for this dramatic colour change was unknown. since then, we do not spray peels anymore, and are very satisfied with the original colours. as such, there was no need to find an alternative impregnation material. in the case that colours are bleak, spraying with hairspray can be a way to intensify colours, but we strongly recommend testing of results along the entire length of the lacquer peel using the trimmed-off edges of the peel. in that case, turn the profile on its side to knock off any loose particles before spraying and ventilate again for a few days before installation. install. after a week of rest when the glue will be firm and odourless, the finished lacquer peel can be installed at its final location. hooks screwed into the top of the board allow hanging it vertically on a wall in a classroom, office, living room, museum, or wherever this piece of science art is desired. if desired, slats can be used to construct a wooden frame around the finished lacquer peel. maintenance. we have heard reports of people annually impregnating their soil peel with spray to ‘maintain its colours’. we have never seen a need for this and do not perform any maintenance of the finished peels. after changing from lacquer to glue, preservation of our peels has improved such that even intensive use in hands-on teaching does not degrade the peels anymore. if required, dust can be carefully removed from between any roots using a vacuum cleaner set at its lowest speed. discussion and conclusion high participation in the maker-ed and diy movements (holtzman et al., ;atkinson, ) indicates renewed interest in making things at home, while the potential of visualization is being recognized in science communication and education (evagorou et al., ;venhuizen et al., in review). at the same time, there is increased interest in the value of soils for life (keesstra et al., ;fao, ). the creation of soil and sediment peels combines all these aspects, and is much easier than many people would think. materials including glues are readily available at hardware stores, and even novices can create beautiful peels. here we discussed the benefits of using peels and the challenges posed by the old methods (e.g. voigt and gittins, ;van baren and bomer, ;bouma, ) used to create these peels. we described the main steps of making a soil peel: impregnation of a smooth soil face with glue in the field before extracting the peel and then mounting it on a wooden panel. because of a technological advance in the impregnation material (going from lacquers to glue), the method reported here is more safe, simple, successful, durable and accessible because ) the glue can be used without the use and mixing of toxic chemicals in the field, ) the firmness of the resulting peel is such that additional support materials (such as cheesecloth) are not required, and ) consequently the soil peel will last for a long time, even when intensively used in hands-on teaching. while this method can be applied to a range of moisture contents and sand textures, further research on the best environmental soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. conditions is required for those interested in achieving perfection in terms of appearance. similar exploration is advised for alternative glues. such additional research would be valuable for some (e.g. soil museums), but based on our experience, we believe that those simply interested in capturing a beautiful snapshot of soils can do so with the more qualitative guidance described in this paper. we hope that this thoroughly tested successful and simple method will inspire and enthuse researchers, educators and the general public to make soil lacquer peels and thereby bring the value and beauty of soils to a wider audience. acknowledgements we thank niels kijm for assistance with making the lacquer peel for the video instructions, bob czaja and ann youberg for discussion of the types of glue that are internationally available, and bison international for information on the characteristics of bisonkit. we furthermore would like to thank the following people for their help in sourcing the data in table : albert bos, alejandro becerra, alessandro samuel rosa, bernd andeweg, christine morgan, coen ritsema, colby moorberg, darya van tienhoven, erin bush, franciska de vries, hayley craig, ichsani wheeler, jacqueline aitkenhead-peterson, jacqueline hannam, jakob wallinga, jantiene baartman, jerry maroulis, jetse stoorvogel, karen vancampenhout, keiko mori, kirsten van der ploeg, liam heffernan, marcos angelini, meredith steele, michael strickland, mirzokhid mirshadiev, nssc-gru, nynke schulp, rachel creamer, richard bardgett, richard kraaijenvanger, stephan mantel, stephan mantel, wieske wentink, wouter thijs, wouter van gorp and zhanguo bai. the authors declare no conflicts of interests. any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by wageningen university and research. c.r.s. has received funding from the european union’s horizon research and innovation programme under the marie skłodowska-curie grant agreement no. . references allaire, s. a., and bochove, e. v.: collecting large soil monoliths, canadian journal of soil science, , - 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, . wright, m.: the preparation of soil monoliths for the ninth international congress of soil science, adelaide, , geoderma, , - , . soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. tuproqshunoslik va agrokimyo ilmiy-tadqiqot instituti (soil science and agrochemistry research institute): http://ygk.uz/uz/node/ , . figure : lacquer peels showing (a) paleo podzol (from below inset) covered by drift sands in which a younger podzol is formed, (b) plaggic anthrosol, (c) sedimentary layering, (d) frost wedge, (e) faulting, and (f) colourful sediments. insets show close-ups of damaged parts of the peel; white horizontal bars represent cm width; panels (a) through (e) are soil and sediment peels made in the netherlands (wageningen university collection, the netherlands), panel (f) is a sediment peel of the owl rock member of the chinle formation, chuska mountains, new mexico usa (diné college collection, tsaile, arizona). soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. figure : main steps of making a soil peel soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. figure : overview of locations suitable for making soil peels in the world (sand content > %, clay content < %, organic matter < %, and temporal mean groundwater depth < . m). this global map was made using soil information obtained from isric (batjes, ;isric, b) and groundwater depth information provided by fan et al. ( ). soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. table : example of museums, universities, schools and institutes with soil profile collections (lacquer peels and/or monoliths) country institute source argentina universidad nacional de río cuarto, instituto nacional de tecnología agropecuaria personal communication marcos angelini, alejandro becerra. australia the university of sydney (australian technology park) personal communication ichsani wheeler austria university of vienna (feigl, ) belgium ku leuven (etwie, ); personal communication karen vancampenhout. brazil universidade federal de lavras, universidade federal de roraima, universidade federal de santa maria. (ufrr, ;ufla, ;ufsm, ). canada university of alberta, university of british colombia, great lakes forestry center (ontario). (krzic et al., ;natural resources canada, ); personal communication liam heffernan. colombia museo de suelos ciro molina garcés, museo de suelos instituto geográfico agustín codazzi. (unal, ;igac, ) china china soil musem; the modern soil monolith exhibition center (giwsr, ;isscas, ) estonia soil museum estonian university of life sciences (eesti maaülikol, ) germany halle university (jahn, ) india kerala forest research institute (kerala forest research institute, ) indonesia museum tanah (bogor soil museum) (ami, ) japan natural museum of history and science, natural resource inventory museum, tsuchino-yakata, hokkaido personal communication keiko mori netherlands world soil museum, wageningen university, vu university, rijksuniversiteit groningen, has hogeschool, vhl university of applied sciences, museonder, geologisch streekmuseum ‘de ijsselvallei’ (isric, a;de hoge veluwe, ;geologisch streekmuseum 'de ijsselvallei', ); personal communication bernd andeweg, richard kraaijvanger, wouter thijs, kirsten van der ploeg. peru museo de suelos (fundacion ilam, ) soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. russia vasily dokuchaev museum of soil science, st petersburg; williams museum of soil and agriculture, moscow (russian museums, ); personal communication jetse stoorvogel spain universidad de murcia, universidad de granada, institut cartogràfic i geològic de catalunya (um, ;ugr, ;lladós et al., ) taiwan national taiwan university, taiwan national research institute (chen, n.d.;churchman and landa, ) thailand soil museum bangkok (thai museums database, ) united arab emirates emirates soil museum (emirates soil museum, ) united kingdom cranfield university personal communication jacqueline hannam united states of america kansas state university, university of idaho, texas a&m, virginia tech, west virginia university, university of georgia, smithsonian's national museum of natural history ( - ), cayuga nature center (ny), diné college (az), american museum of natural history (ny) (univeristy of idaho, ;megonigal et al., b;pri, ;american museum of natural history, ;fitzpatrick et al., ); personal communication colby moorberg, christine morgan, meredith steele. uzbekistan state research institute of soil science and agrochemistry (ygk, ); personal communication mirzokhid mirshadiev soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. table : materials required and their purpose material purpose . g en er al p re pa ra ti on . f ie ld p re pa ra ti on . g lu ei ng . p ee l e xt ra ct io n . m ou nt in g . f in is hi ng ruler, measuring tape to stake out the lacquer peel dimensions x to determine the finished peel dimensions x spade, shovel to make a smooth soil face x to clean up excavated sand x soil knife (nisaku horihori weeding knife, tomita cutlery co. ltd., koseki tsubame-si niigata, japan (alternative: large serrated knife with a nice big handle) to shape the ledge x to dig out the peel after the glue has dried x garden clipper/pruner x nail clippers ( x) to cut small roots x x polychloroprene glue to secure the soil particles x garbage bag, pvc pipe sliced in half to construct a collection unit to capture excess glue x x soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. sturdy garbage bags or bucket to transport empty glue containers (potentially sticky), excess glue x to transport cut off lacquer peel x x notched trowel to evenly spread glue on wooden board x stanley knife to cut off all parts of the lacquer peel that extend beyond the wooden board x workers gloves protect hands during digging etc. x x x latex gloves protect hands while glueing board x wooden board to support extraction and transport of lacquer peel x to mount lacquer peel on x blanket, cloth to prevent lacquer peel from breaking x hooks for mounting on wall x video : instruction video showing how to make a soil peel in the field (uploaded) soil discuss., https://doi.org/ . /soil- - manuscript under review for journal soil discussion started: november c© author(s) . cc by . license. pnas .. sleeping beauty mutagenesis reveals cooperating mutations and pathways in pancreatic adenocarcinoma karen m. manna, , jerrold m. warda, christopher chin kuan yewa, anne kovochichb, david w. dawsonb, michael a. blackc, benjamin t. brettd, todd e. sheetzd,e,f, adam j. dupuyg, australian pancreatic cancer genome initiativeh, , david k. changi,j,k, andrew v. biankini,j,k, nicola waddelll, karin s. kassahnl, sean m. grimmondl, alistair g. rustm, david j. adamsm, nancy a. jenkinsa, , and neal g. copelanda, , adivision of genetics and genomics, institute of molecular and cell biology, singapore ; bdepartment of pathology and laboratory medicine and jonsson comprehensive cancer center, david geffen school of medicine at university of california, los angeles, ca ; cdepartment of biochemistry, university of otago, dunedin, , new zealand; dcenter for bioinformatics and computational biology, university of iowa, iowa city, ia ; edepartment of biomedical engineering, university of iowa, iowa city, ia ; fdepartment of ophthalmology and visual sciences, carver college of medicine, university of iowa, iowa city, ia ; gdepartment of anatomy and cell biology, carver college of medicine, university of iowa, iowa city, ia ; haustralian pancreatic cancer genome initiative; icancer research program, garvan institute of medical research, darlinghurst, sydney, new south wales , australia; jdepartment of surgery, bankstown hospital, bankstown, sydney, new south wales , australia; ksouth western sydney clinical school, faculty of medicine, university of new south wales, liverpool, new south wales , australia; lqueensland centre for medical genomics, institute for molecular bioscience, university of queensland, brisbane, queensland , australia; and mexperimental cancer genetics, wellcome trust sanger institute, hinxton, cambridge cb hh, united kingdom this contribution is part of the special series of inaugural articles by members of the national academy of sciences elected in . contributed by neal g. copeland, february , (sent for review november , ) pancreatic cancer is one of the most deadly cancers affecting the western world. because the disease is highly metastatic and difficult to diagnosis until late stages, the -y survival rate is around %. the identification of molecular cancer drivers is critical for furthering our understanding of the disease and development of improved di- agnostic tools and therapeutics. we have conducted a mutagenic screen using sleeping beauty (sb) in mice to identify new candidate cancer genes in pancreatic cancer. by combining sb with an onco- genic kras allele, we observed highly metastatic pancreatic adeno- carcinomas. using two independent statistical methods to identify loci commonly mutated by sb in these tumors, we identified loci that comprise candidate cancer genes (ccgs); of these ccgs, including mll and ptk , have known mutations in human pancreatic cancer. we identified point mutations in human pancreatic patient samples for another ccgs, including acvr a and map k . impor- tantly, % of the ccgs are involved in chromatin remodeling, in- cluding arid b, kdm a, and nsd , and all sb tumors have at least one mutated gene involved in this process; ccgs, including ctnnd , fbxo , and vgll , are also significantly associated with poor patient survival. sb mutagenesis provides a rich resource of muta- tions in potential cancer drivers for cross-comparative analyses with ongoing sequencing efforts in human pancreatic adenocarcinoma. pancreatic ductal adenocarcinoma is one of the most deadlyforms of cancer. in the united states, the rate of mortality is nearly equal to the rate of new diagnoses ( ). early disease de- tection is rare, and of those patients diagnosed with early-stage disease, only % are candidates for surgical resection. approx- imately % of patients develop highly metastatic disease, for which current treatment regimens provide little increase in lon- gevity ( ). clearly, there is a need for better biomarkers of disease and the identification of new therapeutic targets, particularly for metastatic disease. human pancreatic cancer develops from preinvasive neoplasias, typically intraepithelial neoplasias (panins), although intraductal papillary mucinous neoplasia and mucinous cystic neoplasia can also give rise to adenocarcinoma ( ). the majority of pancreatic adenocarcinoma is of ductal origin and contains a large desmo- plastic component thought to promote tumorigenesis by modu- lating the tumor microenvironment. oncogenic kras mutations are found in % of human tumors, and they appear in early panin ( ). the accumulation of additional inactivating driver mutations in p /cdkn a, tp , and smad occurs with high frequency in later-stage panin, and these mutations are likely required for tumor progression to invasive adenocarcinoma. recent high-throughput sequencing efforts have shown that the majority of somatic point mutations in primary pancreatic adenocarcinoma are missense mutations and that most occur at low frequency ( ). pancreatic cancers exhibit a very unstable ge- nome, and through whole-genome sequencing efforts, a specific type of genomic instability, termed fold-back inversion, has been elucidated ( ). it is clear from these data that characterization of a large number of tumors is required to fully capture the molec- ular heterogeneity of the disease and identify the specific muta- tions and signaling pathways that drive disease progression. pancreatic cancer has been successfully modeled in the mouse by driving expression of oncogenic kras in the pancreas either alone or combined with inactivating alleles of homologs of known human pancreatic cancer drivers ( – ), including smad and trp . all of these models show progressive neoplastic lesions, termed mpanin ( ), and develop locally invasive, and in some cases, metastatic ductal adenocarcinoma. although these models have furthered our understanding of pancreatic cancer biology, new mutations that drive cancer development have not been uncovered in these efforts. we have taken an independent approach to identify genes commonly mutated in a mouse model of pancreatic cancer. we performed an insertional mutagenesis screen using the inducible sleeping beauty (sb) transposon system ( ) in combination with an oncogenic kras pancreatic cancer model. this approach is a powerful means to identify mutations that cooperate with onco- genic kras to drive tumorigenesis in the mouse, because each mutation is mapped using a transposon tag. mice with sb in- sertional mutagenesis exhibit all stages of mpanin lesions. sb decreases the latency of pancreatic tumorigenesis compared with oncogenic kras alone and increases both the severity and author contributions: k.m.m., n.a.j., and n.g.c. designed research; k.m.m., a.k., d.w.d., a.p.g.i., d.k.c., n.w., and k.s.k. performed research; b.t.b., t.e.s., a.j.d., a.g.r., and d.j.a. contributed new reagents/analytic tools; k.m.m., j.m.w., c.c.k.y., d.w.d., m.a.b., b.t.b., a.p.g.i., d.k.c., a.v.b., n.w., k.s.k., s.m.g., and a.g.r. analyzed data; and k.m.m. and n.g.c. wrote the paper. the authors declare no conflict of interest. freely available online through the pnas open access option. present address: cancer biology program, methodist hospital research institute, hous- ton, tx . a complete list of the apgi can be found in the si appendix. to whom correspondence should be addressed. e-mail: ncopeland@tmhs.org. this article contains supporting information online at www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental. – | pnas | april , | vol. | no. www.pnas.org/cgi/doi/ . /pnas. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sapp.docx mailto:ncopeland@tmhs.org http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental www.pnas.org/cgi/doi/ . /pnas. multiplicity of ductal adenocarcinomas. multiple metastases are also observed in a subset of animals. using the transposon tag, we identify candidate cancer genes (ccgs) that show significant enrichment for transposon insertions in sb-driven pancreatic cancer. several signaling pathways and cellular processes are enriched in these ccgs, most significantly tgf-β signaling and chromatin modification. we find genes not previously associated with pancreatic cancer that are significantly associated with poor patient out- come. we also identified point mutations in human homologs of sb ccgs by exome sequencing of patient samples. sb mu- tagenesis is an important tool for the discovery of potential molecular drivers in pancreatic cancer and complements current human sequencing efforts by providing an enriched dataset for cooperating mutations involved in pancreatic adenocarcinoma. results sb drives pancreatic tumorigenesis in the mouse. to identify genes that cooperate with activated kras in pancreatic tumorigenesis, we performed a forward genetic screen in mice carrying a conditional oncogenic krasg d allele (lsl-krasg d) ( ) using sb trans- poson-mediated insertional mutagenesis ( ). mice carrying the lsl-krasg d allele were crossed to mice carrying a pancreatic- specific pdx -cre driver ( ) to remove the floxed stop cassette (lsl) and activate expression of oncogenic krasg d in the pan- creas. these mice were then crossed to a compound transgenic line containing up to copies of a mutagenic sb transposon from a single donor site in the genome, and an inducible sb floxed stop transposase allele knocked into the ubiquitously expressed rosa locus (rosa -lsl-sb ) ( ). because of the presence of the floxed stop cassette, the transposase is not expressed unless cre recombinase protein is present. we used two transposon transgenic lines, t onc and t onc , located on different chromosomes to obtain insertion data from the entire genome. typically, data from a transposon donor chromosome are dis- regarded because of computational limitations in discerning local hopping events from selected transposition events. t onc car- ries a strong promoter derived from the murine stem cell virus, whereas t onc carries the ubiquitously expressed cag pro- moter to activate expression of proto-oncogenes. both trans- posons also carry splice acceptor sites in both orientations and a bidirectional polya signal and they can, therefore, inactivate the expression of tumor suppressor genes when integrated within the coding region in either orientation. five different cohorts of mice carrying different combinations of alleles were bred and aged for tumor formation (fig. ). we observed a significant decrease in tumor-free survival when on- cogenic krasg d was combined with t onc but not t onc (fig. ), although the tumors were more histologically advanced with both t onc and t onc mutagenesis compared with krasg d alone (fig. ). gross inspection of the pancreas at necropsy revealed pancreatic masses that often involved neigh- boring organs (fig. a). metastatic nodules on the liver (fig. b) and lymph nodes (fig. c) were also often seen. the majority of the animals with oncogenic krasg d developed early mpanin lesions as previously reported ( ) (fig. d and e). six animals with oncogenic krasg d alone also developed noninvasive early adenocarcinoma (fig. s a–c), whereas two animals developed spontaneous adenocarcinoma; animals from the krasg d; t onc and krasg d;t onc cohorts developed adenocarci- noma, whereas of these animals developed highly invasive metastatic adenocarcinoma (fig. f). most of the krasg d; t onc animals developed multiple primary pancreatic tumors (two to three on average), and all had metastases to multiple sites associated with the human disease, including lung (fig. g) and lymph nodes (fig. h and i). three animals from the sb cohorts lacking oncogenic krasg d also developed invasive adenocarcinoma. tumors from all cohorts were histologically characterized for markers commonly associated with ductal adenocarcinoma. early mpanin lesions showed high mucin content, which was shown by alcian blue staining, that was reduced in late-stage mpanin lesions and largely absent in adenocarcinomas (fig. s d). mucin accumulates in human panin and may serve as an early bio- marker of disease ( ). fibrosis was also observed in many of the adenocarcinomas, and these adenocarcinomas stained positive for both smooth muscle actin and masson’s trichome for fig. . sb mutagenesis drives pancreatic tumorigenesis in the mouse. five cohorts of mice were aged and monitored for pancreatic tumor de- velopment. all five cohorts carried the pdx -cre driver to activate oncogenic krasg d and sb transposase in the pancreas. krasg d was required for the high frequency induction of pancreatic tumors. animals with oncogenic krasg d and t onc died significantly earlier than animals in the other four cohorts (p < . ). n is the number of animals aged for tumors. cecum mass kidney panin panin panin a b c d e f g h i fig. . histopathological classification of pancreatic lesions. sb mutagenesis generated pancreatic lesions at all stages of tumor progression. (a) mice exhibited pancreatic masses that often involved neighboring organs such as the kidney and cecum. metastatic nodules on the liver (b) and lymph nodes (c) were also often visible on gross inspection. a spectrum of mpanin lesions was also observed with oncogenic krasg d, including early mpanin b lesions (d) showing enlarged cell volume and high mucin content in addition to mpanin and mpanin lesions (e). nineteen animals from the t onc and t onc cohorts developed ductal pancreatic tumors. fourteen animals de- veloped multiple invasive ductal adenocarcinomas (f). several animals also developed multiple metastatic lesions to the lung (g) and lymph nodes (h and i). mann et al. pnas | april , | vol. | no. | m ed ic a l sc ie n c es in a u g u r a l a r ti c le d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf collagen (fig. s e and f). the presence of fibrotic foci is a hallmark of pancreatic cancer, and high levels of smooth muscle actin were recently correlated with poor survival of patients with advanced pancreatic ductal adenocarcinomas ( ). pdx was also reexpressed in both adenocarcinomas and metastases (fig. s g– i), and these lesions were of ductal origin, which was shown by cytokeratin- staining (fig. s j–l). sequence analysis of transposon insertion sites identifies pancreatic ccgs. to identify genes that contribute to pancreatic tumor de- velopment in oncogenic krasg d mice, we pcr-amplified and sequenced the transposon insertion sites from sb-induced pancreatic tumors isolated from animals; tumors were from t onc animals, and tumors were from t onc animals (materials and methods). high-throughput sequencing using the roche titanium platform identified , unique insertion sites that mapped to the mouse genome. these insertion sites were then analyzed using the gaussian kernel convolution (gkc) method to identify common insertion sites (ciss) (si materials and methods) ( ). ciss are regions in the genome that contain more transposon insertions than expected by chance and are most likely to contain a pancreatic cancer gene. the gkc method used -, -, -, -, and -k kernel widths. the outputs for each convolution were merged, and insertions contained within the smallest kernel were used to define the cis (dataset s ). the merged gkc output identified ciss after correcting for multiple testing (p < . ). the cis loci identified ccgs in addition to one riken clone ( l rik), one genome marker (d wsu e), and one predicted gene (gm ). mapping of the , unique sb insertions on a circos plot ( ), which visualizes genome data on a circular layout, showed that the transposon insertions were well-distributed across the genome, with about one-half of the insertions located in the plus strand (fig. , orange lines) and one-half in the minus strand (fig. , purple lines). the gkc cis peaks (fig. , black lines) were also fairly well-distributed across the mouse autosomes with the ex- ception of chromosome , which was devoid of ciss (fig. ). this finding may reflect the fact that the t onc donor concatamer is located on chromosome , and all insertions on this chromosome in t onc tumors were disregarded in the statistical analysis for ciss because of the local hopping phenomenon. the location and directionality of the transposon insertions can be used to predict whether each ccg may function as an onco- gene or tumor suppressor (ts) gene. transposon insertions tend to occur near the ′ end of an oncogene in the same transcrip- tional orientation, where they promote gene expression from the strong promoter within the transposon. in contrast, insertions in ts genes tend to be distributed across the coding region with little orientation bias, consistent with gene inactivation. by mapping the orientation of the transposon with respect to the orientation of the mutated gene, the majority of pancreatic tumor ccgs are pre- dicted to function as ts genes (datasets s and s ). this finding is similar to what has been observed for ccgs identified in trans- poson screens performed in other types of solid tumors ( – ), fig. . circos map of pancreatic cancer candidate cancer genes identified by the gkc method. transposon insertions in the plus (orange lines) and minus (purple lines) strands show genome-wide coverage of mutagenesis. gkc ccgs are illustrated on the outer perimeter of the plot with their exact location denoted by a black line. genes listed in red are mutated in human pancreatic cancer. the blue lines in the center connect bolded gkc ccgs that significantly co-occur in tumors (fisher exact test, p < . ). | www.pnas.org/cgi/doi/ . /pnas. mann et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx www.pnas.org/cgi/doi/ . /pnas. but it is in contrast to what is observed in hematopoietic tumors, where the majority of ccgs seem to function as oncogenes ( ). eighteen pancreatic gkc ccgs ( %) have also been pre- viously shown to be mutated in human pancreatic cancer by exon resequencing or whole-genome sequencing (dataset s ), and they are listed in red on the circos plot in fig. ( , ). these genes are involved in chromatin remodeling (crebbp, ino , mecom, mll , mll , kdm a, and myst ), cell adhesion (ptk and ptprk), protein transport (xpo ), and transcriptional regulation (crebbp, mllt , smad , and zfp ). we also found significant enrichment for pancreatic gkc ccgs in regions containing genomic rearrangements in human pancreatic tumors (n = , p = . e- ) (materials and methods) ( ). in addition, we found significant enrichment of gkc ccgs in the genes listed in the cancer gene census (n = , p = . e- ) (materials and methods and dataset s ). the cancer gene census is an ongoing effort to catalog those genes for which mutations have been causally implicated in cancer ( ). many ccgs are also mutated in other forms of human cancer, which was shown by exon resequencing or whole-genome sequencing, particularly in breast ( %) ( ) and ovarian ( %) cancer (dataset s ) ( ). the degree of overlap with ovarian cancer is likely caused by the large sample size and sequence coverage of the recently annotated ovarian cancer genome by the cancer genome atlas project ( ). cooperating gkc ccgs in sb-induced pancreatic tumors. to identify gkc ccgs that might cooperate in sb-induced pancreatic tu- morigenesis, we performed pairwise comparisons using the fisher exact test to look for significantly comutated loci in the pancreatic cancer genome. we identified pairs of genes with p < . from pairwise comparisons (dataset s ). these co-occurring relationships are shown in the circos plot in fig. by the blue lines in the center connecting co-occurring gkc ccgs (bold font). more than one-half of these genes are involved in regulating cell growth and differentiation (atf , chka, and pten), apoptosis (rere, ctbp , and shb), or cell migration and invasion (abi , ankrd , dstn, fndc b, galnt , pdpk , pten, shb, and socs ). gkc ccgs are enriched for signaling pathways and processes involved in cancer. similar to what has been reported for human tumors, pathway analysis of the pancreatic ccgs using ingenuity pathway analysis (ipa) ( ) suggests that the gkc ccgs function in a limited number of canonical signaling pathways, with many func- tioning in the same signaling pathway (table ) ( , , ). several of these pathways are important for human pancreatic cancer, in- cluding tgf-β, erk/mapk, and wnt/β-catenin signaling path- ways. the pi k/akt signaling axis is also significantly enriched for transposon-induced mutations that predict pathway activation. this finding is consistent with the known relationship between activated ras, akt, and tumor maintenance ( , ). in addition, gkc ccgs are enriched for genes involved in ephrin receptor signaling, table . signaling pathways enriched for ccgs signaling pathways and cellular processes percent tumor number ccg (gkc method) p value number ccg (gcis method) p value representative genes analysis platform molecular mechanisms of cancer . e- . e- crebbp, gsk b, mll , pten, and nsd ipa go: − chromatin modification . e- . e- kdm a, mll , mll , myst , and nsd david tgf-β . e- . e- acvr a, crebbp, smad , smad , and smurf ipa rar activation . e- . e- ncor , nsd , pdpk , and pik r ipa hgf signaling . e- . e- atf , dock , grb , ptk , ptpn , and rap a ipa erk/mapk . e- . e- grb , mapk , pak , and ptk ipa tight junction signaling . e- . e- ash l, ctnna , inadl, magi , and magi kegg go: − chromatin binding . e- . e- adnp, arid b, gata , mbd , and ncoa david pi k/akt . e- . e- mapk , pdpki, pik ca, pten, and rps kb ipa integrin . e- . e- arhgap , itgb , ptk , and rapgef ipa ephrin receptor . e- . e- abi , cdc , epha , gnaq, and gna ipa rac signaling . e- . e- cdc , iqgap , iqgap , map k , and pak ipa formation of filaments . e- . e- akap , atxn , ctnnd , and fhit ipa wnt/β-catenin . e- . e- csnk d, gnaq, gsk β, ep , and ppp r e ipa adherens junction . e- . e- actn , cdh , crebbp, ctnna , and ctnnd kegg analysis of ccgs using ipa, david, and kegg revealed several canonical signaling pathways and processes enriched for ccgs from sb-driven pancreatic tumors. percent tumor is the proportion of tumors that had a mutation in at least one ccg found within the pathway; gkc ccgs and gccgs were significantly enriched in canonical pathways identified by ipa. p values for pathway enrichment were adjusted for multiple testing using the benjamini– hochberg method for control of the false discovery rate. mann et al. pnas | april , | vol. | no. | m ed ic a l sc ie n c es in a u g u r a l a r ti c le d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xls which is important for cytoskeletal reorganization and cell pro- liferation, human growth factor (hgf) signaling, which mediates cell growth through growth factor signaling, and retinoic acid receptor (rar) signaling, which is involved in regulating cell growth and invasion. we also used the database for annotation, visualization and integrated discovery (david) ( , ) to identify cellular pro- cesses that are enriched in the pancreatic ccgs. david is a functional annotation tool used to interrogate gene sets using over annotation categories, including gene ontology terms, protein–protein interactions, and biological pathways. chroma- tin modification was one of the most significantly enriched pro- cesses for ccgs (table ). indeed, all tumors had a mutation in at least one gene encoding a histone-modifying enzyme. several of these genes, including kdm a ( ), mll ( ), and mll ( ), are mutated in several human cancers, pointing to a complex role for epigenetics in human cancer and in particular, pancreatic cancer. filament assembly and specifically actin remodeling are also significantly enriched for gkc ccgs. genes involved in adherens junctions and tight junctions identified using the kyoto encyclopedia of genes and genomes (kegg) were also fre- quently mutated in sb-induced pancreatic cancers. these pro- cesses play important roles in cell invasion and metastasis. gene centric ciss and their potential role in pancreatic cancer. the gkc method identifies ciss by looking for regions in the genome of a given kernel size in which sb insertions occur at a higher frequency than predicted by chance. we reasoned, however, that because the vast majority of ciss in pancreatic tumors encode ts genes and transposon insertions in ts genes are often randomly distributed across the coding region, the gkc method might miss a number of important ciss. we therefore decided to look for ciss by a second gene centric method that does not rely on pat- terns of clustered transposon insertions ( ). this approach con- siders all uniquely mappable ta dinucleotides in the coding region of each refseq gene as a fraction of all uniquely mappable ta dinucleotides in the mouse genome. the population frequency of transposon insertions in each refseq is then calculated (after fil- tering insertions on transposon donor chromosomes). χ analysis is used to calculate the probability of the transposon mutating a ta in a given gene with a higher frequency than predicted by chance. using this approach, we identified gene centric ciss (gciss; p < . ) that contained three or more intragenic inser- tions in at least three independent tumors (dataset s ). three tumors is the minimal number of tumors required to identify a cis by the gkc method, and they represent % of our sb tu- mor cohort. the gcis method identified candidate cancer genes, riken clones, and genomic markers; % of the gkc ciss were also identified by the gcis computational method. we found significant enrichment of gene centric ccgs (gccgs) among the genes listed in the cancer gene census (n = , p = . e- ) (dataset s ). importantly, we also found significant enrichment for gccgs in the genes mutated in human pancre- atic cancer (n = , p = . e- ) or located near sites of ge- nomic rearrangement in human pancreatic cancer (n = , p = . e- ). when we looked for canonical signaling pathways and pro- cesses using gccgs, we found additional genes involved in pathways and processes enriched for pancreatic ccgs that were identified by the gkc method. rac signaling, involved in actin polymerization as well as hgf, ephrin receptor, integrin, and wnt/β-catenin signaling pathways, showed significant enrichment for gccgs (table ). in addition, genes involved in tight junc- tions and adherens junctions were significantly enriched for gccgs as were genes involved in chromatin modification. these data indicate that the gcis method identifies additional candi- date cancer genes important for pancreatic adenocarcinoma in our model. ccgs in sb-driven pancreatic cancer predict human pancreatic cancer patient survival. we next wanted to assess whether any of the gkc ccgs that we identified in our transposon screen had a significant impact on human pancreatic cancer. we used expression array data from human pancreatic tumors available from the national center for biotechnology information gene expression omnibus database ( , ) (gse ) for which patient survival data were available ( ). we considered a ccg as being validated if at least one of the probe sets on the array had a significant association with patient survival (based on cox proportional hazards regression) after p value adjustment for multiple testing (si materials and methods). based on these criteria, gkc ccgs were signifi- cantly associated with patient survival in this dataset. fig. s shows the survival curves generated by dividing the samples into high and low expression groups at different percentiles; of genes showed a positive correlation between the predicted mutagenic effect of sb transposition in mouse pancreatic tumors (i.e., gene activation or inactivation) and gene expression levels associated with poor survival in the human tumors. the probability of ob- taining this result by chance was . . this work reports crkrs, pard g, pum , socs , and zfx as candidate oncogenes and akap , ctnnd , dyrk a, fbxo , gsk b, myo d, vgll , zc h a, and zfand as candidate tumor suppressors in human pancreatic cancer. we then interrogated a tissue microarray comprised of three- replicate -mm cores from patients with pancreatic adeno- carcinoma ( ) for levels of protein encoded by frequently mu- tated ccgs found in enriched signaling pathways. for two proteins, ctnnd and gnaq, we observed a decrease or ab- sence of staining in tumors with intact staining in adjacent benign ducts or acini present within the same core (fig. ). ctnnd is membrane-bound and plays a role in adherens junctions by regulating e-cadherin ( ); it has also been shown to regulate wnt signaling ( ). gnaq is a cytoplasmic guaninine–nucle- otide binding protein that signals to rhoa and is implicated in cell proliferation and migration ( ). low staining for ctnnd (p = . ) was significantly associated with poor survival (fig. ) using a univariate cox analysis of overall survival (si materials and methods), whereas low staining for gnaq showed a bor- derline significant association with poor survival (p = . ). analysis of ctnnd staining in a second independent pancre- atic cancer tissue microarray of patient samples ( , ) confirmed that decreased ctnnd is significantly associated with poor survival in pancreatic cancer patients who underwent operative resection (fig. s ). these data also substantiate that disruption of genes participating in cell–cell interactions and regulation of cell migration in sb-driven pancreatic tumors have biological relevance to disease. exome sequencing from human pancreatic cancer patients uncovers damaging point mutations. finally, we investigated the coding mutation status of the gkc ccgs in human pancreatic cancer patient samples. we queried the australian pancreatic cancer genome initiative exome sequence mutation discovery database, which was created from a collection of pancreatic cancer patient dnas with matched normal controls. surprisingly, gkc ciss exhibited coding mutations in at least one patient. we validated nonsilent coding mutations in nine human homologs of the mouse gkc ciss in these samples using targeted pcr and ion torrent sequencing at > , -fold depth of coverage. these homologs are acvr a, aff , ap g , crebbp, meis , mkln , mll , smad , and thsd a (dataset s ). in addition, mutations in ctnna and map k , two human homologs of sb ccgs iden- tified using the gcis method, were also validated. loss of smad is a well-documented driver in human pancreatic cancer and mouse models. the work by jones et al. ( ) previously identified mutations in mll , a member of the mixed lineage leukemia gene family, in both their exome discovery and validation screens for | www.pnas.org/cgi/doi/ . /pnas. mann et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=sf http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/sd .xlsx www.pnas.org/cgi/doi/ . /pnas. pancreatic cancer mutations. crebbp, which encodes an acety- lase that targets histones and nonhistones, and ctnna , an ortholog of ctnnd also involved in cell adhesion, were also identified in their discovery screen. seven of the validated gkc ciss are unique. the majority of the mutations in these genes are missense, although nonsense mutations were identified in two genes—acvr a, which enc- odes a type ii receptor of the tgf-β superfamily that also par- ticipates in integrin signaling, and map k , which is involved in jun kinase activation. interestingly, all genes with validated mutations are predicted to be potential tumor suppressors by our screen. we also validated mutations in orthologs of four gkc ciss that encode proteins with similar biological function. aff is an ortholog of the gkc cis aff , which encodes proteins involved in both splicing and transcriptional control. dock and dock are orthologs of the gkc cis dock (dock ), which is involved in rac signaling. thsd b, mutated in the discovery screen by jones et al. ( ) and an ortholog of thsd a, is also mutated in the australian pancreatic cancer genome initiative cohort. given the heterogeneity of mutations in pan- creatic cancer, it is encouraging that many of our sb ccgs have validated mutations in a cohort of only patients. additional experimentation is required to determine the impact of these mutations on disease development and prognosis. discussion we report an sb insertional mutagenesis screen to identify loci that cooperate with oncogenic kras to drive pancreatic adenocarcinoma in the mouse. sb-driven pancreatic adenocarcinomas show all stages of mpanin that develop into early noninvasive adenocarci- noma and finally, invasive, highly metastatic adenocarcinoma. im- portantly, these tumors also have a high desmoplastic component, a predominant histopathic feature of human pancreatic cancer. the t onc transposon proved to be more potent than t onc in inducing metastatic tumors. the exact mechanism for the differ- ence between the two transposons in driving pancreatic cancer is unknown. one possibility is that the location of the transposon concatemer donor influences the development of the tumor. the t onc donor resides on chromosome , and pancreatic cancer genes in close proximity may be frequently mutated in these tumors because of local hopping. both t onc and t onc cohorts exhibited considerably higher numbers of nonredundant insertions per tumor relative to the number of transposons in the donor concatemer (fivefold greater insertions for t onc and -fold greater insertions for t onc on average). the large number of mapped insertions ( , from independent tumors) is likely because of the fact that many insertions are background passengers as opposed to driver mutations, and it also reflects the oligoclonality of these tumors. using both the gkc and the gcis methods, we identified statistically significant ciss that comprise pancreatic ccgs. the tumor heterogeneity makes it difficult to identify co- occurrence of insertions in individual subclones. one way to begin to address this issue is to use laser capture microdissection to determine the transposon insertion profiles in tumor subclones. ultimately, it will take single-cell sequencing to understand the degree of heterogeneity in pancreatic and other solid tumors. the majority of the genes that we identified in our sb pancreatic insertional mutagenesis screen ( %) are predicted to be disrupted based on the orientation of the transposon with respect to the gene. for most ciss, only one transposon insertion is observed per tu- mor, although there are examples of tumors with multiple inser- tions that contribute to a cis. we believe that these singly mutated genes do play a role in pancreatic cancer for several reasons. many of these ts genes function in known signaling pathways in cancer, and they are found mutated in human cancer with a frequency greater than predicted by chance. indeed, ccgs overlap with genes mutated or deleted in human pancreatic adenocarcinoma from published sequencing efforts. in addition, although solid tumors induced by sb seem to select for loss of function mutations ( , ), sb-induced hematopoietic cancers seem to select for oncogenes. this finding argues that there is something special about solid tumors that selects for loss of function mutations. some of the ciss that we identified may represent haploinsufficient fig. . ctnnd and gnaq show absent or weak staining in human pancreatic tumors. immunohistochemistry was performed on a human pancreatic tissue microarray for (a) ctnnd and (b) gnaq. arrows indicate tumors with weak or absent staining, whereas adjacent benign ducts or acini (indicated by white arrowheads) verify the presence of intact staining in tissue sections. weak or absent staining of (c) ctnnd (log rank p = . ) and (d) gnaq (log rank p = . ) is predictive of poor survival. kaplan–meier plots (c and d) of patient survival represent two patient groups dichotomized into the top two tertiles (green) vs. bottom tertile (blue) using the histoscore for high and low staining. mann et al. pnas | april , | vol. | no. | m ed ic a l sc ie n c es in a u g u r a l a r ti c le d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , tumor suppressors, a recent example being fbxo in b-cell lym- phoma ( ). alternatively, acquired point mutation, rearrange- ment, or epigenetic silencing may be the preferred mechanism for inactivating the second allele in solid tumors. analysis of the human pancreatic cancer genome by se- quencing snp and comparative genomic hybridization (cgh) arrays has shown that chromosome loss or gene deletions are frequent events in human pancreatic cancer ( , , ). missense mutations predominate the pancreatic genome mutational landscape. using an algorithm to predict the significance of cancer-associated mutations (i.e., not passengers), the work by jones et al. ( ) reported that % of the missense mutations identified in their discovery set for human pancreatic cancer are likely to contribute to tumorigenesis. our sb-driven pancreatic tumors provide an enriched dataset of frequently mutated genes that include many of the genes mutated in the human discovery set. these genes include mecom (mutated in % of sb-driven pancreatic tumors), mll , ptprk, zc h a (each mutated in % of tumors), and ino (mutated in % of tumors). we also find transposon insertions in several genes identified in the work by campbell et al. ( ) to be either deleted (pkt , slc a , and xpo ) or involved in intra- (kdm a and myo d) or in- terchromosomal (mllt ) rearrangements that are each mu- tated in > % of the sb pancreatic tumors. the high mutation frequency of these genes and others in our sb screen provides evidence that many of the ccgs may indeed be drivers of pancreatic cancer. we also identified nonsilent mutations in eleven ccgs in human pancreatic cancer patient samples from the australian pancreatic cancer genome initiative. we antic- ipate that additional mutations in human homologs of sb ccgs will be identified in human pancreatic cancer as more patient samples are sequenced. the most significantly mutated gene identified by both the gkc and gcis methods is pten. mutations in this tumor sup- pressor gene have not been identified in pancreatic cancer, al- though the chromosomal region in which it lies on q does undergo loss of heterozygosity ( – ). inactivation of pten in the mouse, recently shown to cooperate with oncogenic kras to drive pancreatic adenocarcinoma ( ), may be the easiest way to de- regulate akt signaling in the mouse. although tp mutations are frequent in human pancreatic cancer, we do not detect trp as a cis in our screen. however, we do find mutations in a number of genes in the trp pathway, including crebbp, jmy, and mapk . usp x, the second most significantly mutated gene in our screen and predicted to be inactivated, has not been associ- ated as a tumor suppressor with any cancer, although point mutations have been identified in breast ( ), lung ( ), and ovarian cancers ( ). usp x encodes a deubiquitinase that has been shown to stabilize mcl in several tumor types ( ). we identify several genes in our screen involved in ubiquitin-medi- ated protein degradation, a few of which (arih , fbxo , ubr , and usp ) have mutations in human cancer. fbxo has been shown to modulate tgf-β signaling in a mouse mutant ( ) and influence trp neddylation ( ). ubr , also known as edd, has a number of potential targets, including β-catenin ( ). remarkably, % of the pancreatic ccgs that we identify function in chromatin remodeling, and % of tumors had a mutation in at least one of these genes. mll is a component of the asc- containing (ascom) complex involved in h k trimethy- lation, a histone modification associated with gene activation ( ). this complex also contains kdm a, suggesting that this h k trimethyl-demethylase may also have a role in methylating h k . mutations were also found in whsc l (nsd ), a methyltransferase known to target both h k and h k . analyses of methylation patterns and patient outcome in human pancreatic ductal adeno- carcinoma have shown that low levels of histone methylation are generally predictors of poor survival ( , ). recent findings from exome sequencing of pancreatic neuroendocrine tumors show that chromatin remodeling and specifically, inactivating mutations in men , a component of mll - and mll -h k methyl- transferase complexes, play important roles in this disease as well ( ). identification of the genes regulated by these epigenetic marks will be critical to understanding how epigenetic mechanisms can modulate pancreatic cancer. our data support the observations made in the work by jones et al. ( ) that a limited number of canonical signaling pathways are mutated in the majority of pancreatic tumors. we find sig- nificant enrichment for sb ccgs in known signaling pathways involved in pancreatic cancer, including tgf-β, wnt/β-catenin, and integrin signaling. importantly, we identify genes involved in these enriched pathways that have not been reported as mutated in human pancreatic cancer. the mutational heterogeneity in sb tumors may arise from the plasticity of pathways that permits deregulation by a number of distinct genetic alterations. this finding argues for a need to better understand pathway pertur- bations in cancer at the cellular level rather than at the gene level. sb insertional mutagenesis shows great power for identifying candidate cancer genes with direct relevance to human cancers. our model of sb-driven pancreatic adenocarcinoma shows all stages of pancreatic lesions leading up to adenocarcinoma and metastasis. the ease of mapping transposon insertion sites within the cancer genome makes it possible to interrogate the gene perturbations that occur at each stage, which can potentially lead to the identification of cancer drivers required for the initiation, progression, and metastasis of pancreatic adenocarcinoma. the significant overlap of our findings with sequencing data from human tumors highlights the relevance of this pancreatic cancer mouse model to human pancreatic adenocarcinoma. data from the sb-driven pancreatic tumors will undoubtedly aid in the prioritization and validation of forthcoming human sequencing data from pancreatic adenocarcinoma. materials and methods mice. we used the following alleles to generate a mouse model of pancreatic cancer: lsl-krasg d ( ), pdx -cre ( ), t onc ( ) ( ), t onc ( ), and rosa -lsl-sb ( ). the resulting cohorts were on a mixed b . genetic background. all animals were monitored on a biweekly basis in accordance with the institutional animal care and use committee guide- lines. gross necropsies were performed, and one-half of the pancreas was snap-frozen; the other one-half (retaining the duodenum) was fixed and paraffin-embedded. all masses larger than mm were recovered; one-half was snap-frozen, and the other one-half was fixed and paraffin-embedded. cloning and mapping transposon insertions sites. isolation of the transposon insertion sites was performed using splinkerette pcr to produce barcoded pcr products that were pooled and sequenced on the gs-titanium sequencers (roche) platform. reads from sequenced tumors were mapped to the mouse genome assembly national center for biotechnology information m and merged together to identify nonredundant sb insertion sites (si materials and methods). acknowledgments. the authors thank keith rogers, susan rogers, and the institute for molecular and cell biology histopathology core. we thank doug melton for the pdx -cre animals and angela chou, anatomical pa- thologist at the garvan institute of medical research, for performing the second blinded scoring for the tissue microarray. we also acknowledge pear- lyn cheok, nicole lim, and dorothy chen for their help with tumor moni- toring. this work was supported in part by the biomedical research council, agency for science, technology, and research, singapore; the national health and medical research council of australia; the queensland govern- ment; the cancer council new south wales; the cancer institute new south wales; the royal australian college of surgeons; the australian cancer re- search foundation; the st. vincent’s clinic foundation; the avner nahmani pancreatic cancer foundation; and the r. t. hall trust. | www.pnas.org/cgi/doi/ . /pnas. mann et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=stxt www.pnas.org/cgi/doi/ . /pnas. . jemal a, siegel r, xu j, ward e ( ) cancer statistics, . ca cancer j clin : – . . stathis a, moore mj ( ) advanced pancreatic carcinoma: current treatment and future challenges. nat rev clin oncol : – . . maitra a, fukushima n, takaori k, hruban rh ( ) precursors to invasive pancreatic cancer. adv anat pathol : – . . hansel de, kern se, hruban rh ( ) molecular pathogenesis of pancreatic cancer. annu rev genomics hum genet : – . . jones s, et al. 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( ) a modified sleeping beauty transposon system that can be used to model a wide variety of human cancers in mice. cancer res : – . mann et al. pnas | april , | vol. | no. | m ed ic a l sc ie n c es in a u g u r a l a r ti c le d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.ingenuity.com are these the most beautiful? are t h e s e the m o s t beautiful? d a v i d w e l l s in the fall mathematical intelligencer (vol. , no. ) ( ) readers were a s k e d to evaluate theorems, o n a scale from to , for b e a u t y . i received c o m p l e t e d ques- ( ) tionnaires, i n c l u d i n g f r o m a p r e l i m i n a r y v e r s i o n (plus extra, n o t e d below.) o n e p e r s o n a s s i g n e d each t h e o r e m a score of , ( ) w i t h the comment, " m a t h s is a tool. art h a s b e a u t y " ; that r e s p o n s e w a s excluded from the averages listed below, as w a s a n o t h e r that a w a r d e d v e r y m a n y zeros, ( ) four w h o left m a n y blanks, a n d two w h o a w a r d e d nu- m e r o u s s. the t h e o r e m s are listed below, o r d e r e d b y their average score from t h e remaining responses� rank ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) theorem average d ~' = - . euler's formula for a polyhedron: . v + f = e + the n u m b e r of primes is infinite. . there are regular polyhedra. . + ~ + ~ + ~ + . . . = "rr / . . a c o n t i n u o u s m a p p i n g of the . closed u n i t disk into itself has a fixed point. there is no rational n u m b e r w h o s e . square is . ~r is transcendental. . every plane m a p can be coloured . with colours. every prime n u m b e r of the form . n + is the s u m of t w o integral squares in exactly o n e way. ( ) the order of a s u b g r o u p divides . t h e order of the group. a n y square matrix satisfies its . characteristic equation. a regular icosahedron inscribed in . a regular o c t a h e d r o n divides the e d g e s in the g o l d e n ratio. . x x x x + x x , r r - � " if the points of the plane are each . coloured red, yellow, or blue, the mathematical intelligencer vol. , n o . � springer-verlag new york there is a pair of points of the s a m e colour of m u t u a l distance unity. ( ) the n u m b e r of partitions of an . integer into o d d integers is equal to the n u m b e r of partitions into distinct integers. ( ) every n u m b e r greater than is . the s u m of integers, the s u m of w h o s e reciprocals is . ( ) the n u m b e r of representations of . an o d d n u m b e r as the s u m of squares is times the s u m of its divisors; of an e v e n number, times the s u m of its o d d divisors. ( ) there is n o equilateral triangle . w h o s e vertices are plane lattice points. ( ) at a n y party, there is a pair of . p e o p l e w h o h a v e the same n u m b e r of friends present. write d o w n the multiples of r o o t , ignoring fractional parts, a n d u n d e r n e a t h write the n u m b e r s missing from the first sequence. the difference is n in the nth place. the w o r d p r o b l e m for g r o u p s is unsolvable. ( ) . ( ) . ( ) the m a x i m u m area of a . quadrilateral with sides a , b , c , d is [(s - a ) ( s - b ) ( s - c ) ( s - d)] w, w h e r e s is half the perimeter. [ ( - - x ) ( - - x l o ) ( i - - x . . � ( ) [( - x)( - x )( - x )( - x )... . = p( ) + p( )x + p( )x a + . . . . w h e r e p ( n ) is the n u m b e r of partitions of n. the following c o m m e n t s are divided into themes. unattributed q u o t e s are from r e s p o n d e n t s . t h e m e : a r e t h e o r e m s b e a u t i f u l ? t o n y gardiner a r g u e d that " t h e o r e m s aren't usually 'beautiful'. it's the ideas a n d p r o o f s that a p p e a l , " and r e m a r k e d of the t h e o r e m s he h a d n o t s c o r e d , " t h e r e s t are h a r d to s c o r e - - e i t h e r b e c a u s e t h e y a r e n ' t really beautiful, h o w e v e r important, or b e c a u s e the formulation given gets in the w a y . . . . " several re- s p o n d e n t s disliked j u d g i n g t h e o r e m s . ( h o w m a n y r e a d e r s did n o t reply for such reasons?) benno a r t m a n n w r o t e "for m e it is impossible to j u d g e a 'pure fact' "; this is consistent with his interest in bourbaki and the axiomatic d e v e l o p m e n t of struc- tures. t h o m a s drucker: " o n e d o e s n o t have to be a rus- sellian to feel that m u c h of mathematics has to d o w i t h deriving consequences from a s s u m p t i o n s . as a result, a n y ' t h e o r e m ' cannot b e i s o l a t e d from the a s s u m p - tions u n d e r w h i c h it is d e r i v e d . " g e r h a r d domanski: " s o m e t i m e s i find a p r o b l e m m o r e beautiful than its solution. i find also b e a u t y in m a t h e m a t i c a l i d e a s or c o n s t r u c t i o n s , s u c h as t h e turing machine, fractals, twistors, and so on . . . . the ordering of a w h o l e field, like the w o r k of bourbaki � . . is of great b e a u t y to m e . " r. p. lewis writes, ' ( ) . . . i a w a r d points n o t so m u c h for the equation itself as for complex analysis as a w h o l e . ' to w h a t extent w a s the g o o d score for ( ) a v o t e for the b e a u t y of the platonic solids themselves? t h e m e : s o c i a l factors might s o m e votes have g o n e to ( ), ( ), ( ), ( ), a n d ( ) b e c a u s e t h e y are ' k n o w n ' to b e beautiful? i am suspi- cious t h a t ( ) received so m a n y scores in the - range. this w o u l d surprise me, because i suspect that m a t h e m a t i c i a n s are m o r e i n d e p e n d e n t t h a n m o s t p e o p l e [ ] of others' opinions. (the ten extra forms referred to a b o v e came from eliot jacobson's s t u d e n t s in his n u m b e r theory course that emphasises the role of b e a u t y . i n o t e d that t h e y gave no zeros at all.) t h e m e : c h a n g e s i n a p p r e c i a t i o n o v e r t i m e there w a s a notable n u m b e r of l o w scores for the high rank theorems� le lionnais has one explanation [ ]: "euler's formula e i~' = - establishes w h a t a p p e a r e d in its time to be a fantastic connection b e t w e e n the m o s t i m p o r t a n t n u m b e r s in mathematics . . . it w a s g e n e r a l l y c o n s i d e r e d 'the m o s t b e a u t i f u l formula of mathematics' . . . t o d a y the intrinsic reason for this c o m p a t i b i l i t y has b e c o m e so o b v i o u s that the s a m e formula n o w seems, if n o t insipid, at least entirely nat- u r a l . " le lionnais, u n f o r t u n a t e l y , d o e s n o t qualify " n o w s e e m s " b y asking, "'to w h o m ? " h o w d o e s j u d g m e n t c h a n g e w i t h time? b u r n s i d e [ ], r e f e r r i n g to % g r o u p w h i c h is . . . a b s t r a c t l y e q u i v a l e n t to t h a t of t h e p e r m u t a t i o n s of f o u r s y m b o l s , " wrote, "in the latter form the problem pre- s e n t e d w o u l d to m a n y minds b e almost repulsive in its n a k e d f o r m a l i t y . . . " earlier [ ], perspective projection was, "'a process o c c a s i o n a l l y r e s o r t e d to b y g e o m e t e r s of o u r o w n country, b u t generally e s t e e m e d . . , to b e a species of the mathematical intelligencer vol. , no. , 'geometrical trickery', b y which, 'our notions of ele- gance or geometrical purity m a y be violated . . . . ' " i a m sympathetic to tito tonietti: "'beauty, even in m a t h e m a t i c s , d e p e n d s u p o n historical a n d cultural contexts, and therefore t e n d s to elude numerical inter- pretation." compare the psychological concept of habituation. can a n d do mathematicians deliberately u n d o such ef- fects b y placing themselves empathically in t h e posi- tion of the original discoverers? g e r h a r d domanski w r o t e o u t the entire question- n a i r e b y h a n d , e x p l a i n i n g , " a s i w r o t e d o w n t h e t h e o r e m i tried to r e m e m b e r t h e feelings i h a d w h e n i first h e a r d of it. in this w a y i gave the scores." theme : simplicity and brevity n o criteria are m o r e often associated with b e a u t y than simplicity a n d brevity. m. gunzler w i s h e d ( ) h a d a simpler proof. david halprin wrote "'the b e a u t y that i find in mathematics � . . is m o r e to be f o u n d in the clever and/or succinct w a y it is p r o v e n . " d a v i d s i n g m a s t e r m a r k e d ( ) d o w n somewhat, because it does n o t have a simple proof. i feel that this indicates its d e p t h a n d m a r k it u p accordingly. are there no s y m p h o n i e s or epics in the world of beautiful proofs? some chess players prefer t h e ele- g a n t simplicity of t h e e n d g a m e , others appreciate the complexity of t h e m i d d l e game. either way, pleasure is derived from t h e reduction of complexity to sim- plicity, b u t the p r e f e r r e d level of complexity differs from player to player. are mathematicians similarly varied? roger p e n r o s e [ ] a s k e d w h e t h e r a n u n a d o r n e d square grid was beautiful, or was it too simple? he c o n c l u d e d that h e p r e f e r r e d his non-periodic tessella- tions. but the question is a good one. h o w simple can a beautiful entity be? are easy t h e o r e m s less beautiful? o n e r e s p o n d e n t m a r k e d d o w n ( ) a n d ( ) for being "too e a s y , " a n d ( ) for being "'too difficult." david gurarie m a r k e d d o w n ( ) a n d ( ) for being too simple, a n d a n o t h e r r e s p o n d e n t r e f e r r e d to t h e o r e m s t h a t a r e t r u e b y v i r t u e of t h e definition of their terms, w h i c h could have b e e n a dig at ( ). t h e o r e m ( ) is extraordinarily simple b u t m o r e t h a n a quarter of t h e r e s p o n d e n t s scored it + . theme : surprise y a n n i s h a r a l a m b o u s w r o t e : " a b e a u t i f u l t h e o r e m m u s t be surprising a n d deep. it m u s t provide y o u with a n e w vision o f . . . m a t h e m a t i c s , " a n d m e n t i o n e d the p r i m e n u m b e r t h e o r e m (which was by far t h e most popular suggestion for t h e o r e m s that o u g h t to h a v e b e e n i n c l u d e d in the quiz). r. p. lewis: "( ) is top of m y list, because it is sur- prising, n o t r e a d i l y g e n e r a l i z a b l e , a n d difficult to prove. it is also i m p o r t a n t . " ( + in the margin!) j o n a t h a n watson criticised a lack of novelty, in this sense: "( ), ( ), ( ) . . . s e e m to tell u s little that is n e w about the concepts that a p p e a r in t h e m . " penrose [ ] qualifies atiyah's suggestion "that ele- gance is m o r e or less s y n o n y m o u s with simplicity" b y d a i m i n g that " o n e should say that it has to do w i t h unexpected simplicity." surprise a n d novelty are expected to provoke e m o - tion, o f t e n pleasant, b u t also o f t e n negative. n e w styles in p o p u l a r a n d h i g h c u l t u r e h a v e a n o v e l t y value, albeit temporary. as usual there is a psycholog- ical connection. h u m a n beings d o not r e s p o n d to just a n y stimulus: t h e y do t e n d to r e s p o n d to novelty, sur- p r i s i n g n e s s , incongruity, a n d complexity. but w h a t h a p p e n s w h e n t h e novelty wears off? surprise is also associated with mystery. einstein asserted, " t h e m o s t beautiful t h i n g w e can experience is t h e mysterious. it is the source of all true art a n d science." but w h a t h a p p e n s w h e n the m y s t e r y is re- solved? is t h e b e a u t y t r a n s f o r m e d into a n o t h e r beauty, or m a y it evaporate? i i n c l u d e d ( ) a n d ( ) because t h e y initially mysti- fied a n d surprised me. at second sight, ( ) remains so, a n d scores quite highly, but ( ) is at most pretty. (how do mathematicians t e n d to distinguish b e t w e e n beautiful a n d pretty?) theme : depth look at t h e o r e m ( ). oh, come o n now, ladies a n d g e n t l e m e n ! please! i s n ' t this difficult, d e e p , sur- prising, a n d s i m p l e relative to its s u b j e c t matter?! what m o r e d o y o u want? it is q u o t e d by littlewood [ ] in his r e v i e w of r a m a n u j a n ' s collected w o r k s as of "'supreme b e a u t y . " i w o n d e r e d w h a t readers w o u l d think of it: b u t i n e v e r s u p p o s e d that it w o u l d rank last, with ( ), ( ), a n d ( ). r. p. l e w i s i l l u s t r a t e d t h e v a r i e t y of r e s p o n s e s w h e n h e suggested that a m o n g t h e o r e m s n o t included i could h a v e c h o s e n " m o s t of r a m a n u j a n ' s work,'" adding, "'( ) is pretty, but easy to prove, a n d not so d e e p . " d e p t h s e e m s n o t so i m p o r t a n t to r e s p o n d e n t s , w h i c h m a k e s m e feel that m y interpretation of d e p t h m a y be idiosyncratic. i was surprised that t h e o r e m ( ), w h i c h is s u r e l y d e e p , ranks b e l o w ( ), to w h i c h le l i o n n a i s ' s a r g u m e n t m i g h t a p p l y , b u t ( ) has n o simple proof� is simplicity that important? ( ) also scored poorly. is it n o longer deep or diffi- cult? alan laverty a n d alfredo octavio suggested that it w o u l d be h a r d e r a n d more beautiful if it a n s w e r e d the mathematical intell gencer vol. , n o . , ~ the same problem for non-zero squares. daniel s h a n k s once a s k e d w h e t h e r t h e quadratic reciprocity law is deep, a n d concluded that it is not, a n y longer. c a n loss of d e p t h h a v e d e s t r o y e d t h e b e a u t y of ( )? t h e m e : f i e l d s o f interest robert a n d e r s s e n a r g u e d that j u d g e m e n t s of mathe- matical b e a u t y "will n o t be universal, b u t will d e p e n d on the b a c k g r o u n d of the mathematician (algebraist, geometer, analyst, etc.)" s. liu, writing from p h y s i c s r e v i e w (a h a n d f u l of re- s p o n d e n t s identified themselves as n o n - p u r e - m a t h e - maticians), a d m i t t e d "'my answers reflect a preference for the algebraic a n d number-theoretical over the geo- metrical, topological, a n d analytical t h e o r e m s , ' a n d c o n t i n u e d : "i love classical euclidean g e o m e t r y - - a subject w h i c h originally attracted m e to mathematics. however, within t h e context of y o u r questionnaire, the p u r e l y geometrical t h e o r e m s pale by comparison." should readers h a v e been asked to r e s p o n d only to those t h e o r e m s w i t h w h i c h t h e y w e r e extremely fa- miliar? ( ) is t h e only item that should n o t have been included, because so m a n y left it blank. was it outside the m a i n field of interest of most r e s p o n d e n t s , a n d rated d o w n for that reason? t h e m e : d i f f e r e n c e s i n form t w o r e s p o n d e n t s s u g g e s t e d that e i " + = w a s (much) superior, combining " t h e five m o s t important constants." can a small a n d "inessential" c h a n g e in a t h e o r e m c h a n g e its aesthetic value? h o w w o u l d i i = e -~'t have scored? two n o t e d that ( ) is equivalent to t h e irrationality of v a n d o n e s u g g e s t e d that ( ) a n d ( ) are equiva- lent. equivalent o r related? w h e n inversion is applied to a t h e o r e m in euclidean g e o m e t r y are the n e w a n d original t h e o r e m s automati- cally perceived as equally beautiful? i feel not, a n d nat- urally n o t if surprise is an aesthetic variable. a r e a t h e o r e m a n d its d u a l e q u a l l y b e a u t i f u l ? d o u g l a s h o f s t a d t e r s u g g e s t e d t h a t d e s a r g u e s ' s t h e o r e m (its o w n dual) might have b e e n included, a n d w o u l d h a v e g i v e n a v e r y h i g h s c o r e to m o r l e y ' s t h e o r e m on t h e trisectors of the angles of a triangle. now, morley's t h e o r e m follows from t h e trigonomet- rical identity, / sin = [sin ] [sin (~/ - )] [sin ('rr/ + )]. h o w come o n e particular transformation of this iden- tity into triangle terms is t h o u g h t so beautiful? is it partly a surprise factor, w h i c h the p e d e s t r i a n identity lacks? t h e m e : general versus s p e c i f i c h a r d l y t o u c h e d on by r e s p o n d e n t s , t h e question of general vs. specific seems important to me so i shall quote paul halmos [ ]: "'stein's (harmonic analysis) a n d shelah's (set theory) . . . r e p r e s e n t what s e e m to be t w o diametrically opposite psychological attitudes to m a t h e m a t i c s . . . the contrast b e t w e e n t h e m can be described (inaccurately, b u t p e r h a p s suggestively) b y the w o r d s special a n d general . . . . stein talked about singular integrals . . . [shelah] said, early on: 'i love m a t h e m a t i c s because i love generality,' a n d he was off a n d r u n n i n g , classifying structures w h o s e elements w e r e structures of structures of structures." f r e e m a n d y s o n [ ] has discussed w h a t he calls "ac- cidental b e a u t y " a n d associated it with unfashionable mathematics. roger sollie, a physicist, admitted, "i t e n d to favour 'formulas' involving ~r," a n d scored ( ) almost as high as ( ) a n d ( ). is "rr, a n d a n y t h i n g to do w i t h it, coloured b y the feeling that -a" is unique, that there is n o other n u m b e r like it? t h e m e : idiosyncratic r e s p o n s e s several readers illustrated t h e b r e a d t h of individual responses. mood was relevant to alan laverty: " t h e scores i gave to [several] w o u l d fluctuate according to m o o d a n d c i r c u m s t a n c e . e x t r e m e example: at o n e point i w a s considering giving ( ) a , but i finally d e c i d e d it just d i d n ' t thrill m e v e r y m u c h . " he gave i t a . shirley ulrich "'could n o t assign comparative scores to t h e . . . items considered as one g r o u p , " so split t h e m into geometric items a n d n u m e r i c items, a n d scored each group separately. r. s. d. thomas wrote: "i feel that negativity [( ), ( ), ( ) a n d ( )] makes b e a u t y h a r d to achieve.'" philosophical orientation came out in the response of j o n a t h a n w a t s o n (software designer, p h i l o s o p h y major, r e a d s m a t h e m a t i c a l i n t e l l i g e n c e r for foundational interest): "i a m a c o n s t r u c t i v i s t . . , a n d so l o w e r e d t h e score for ( ), a l t h o u g h y o u c a n also e x p r e s s t h a t t h e o r e m constructively." he adds, " . . . the question- n a i r e i n d i r e c t l y r a i s e s f o u n d a t i o n a l i s s u e s - - o n e t h e o r e m is as true as another, b u t b e a u t y is a h u m a n criterion. a n d b e a u t y is tied to u s e f u l n e s s . " c o n c l u s i o n from a small survey, crude in construction, no posi- tive conclusion is safe. h o w e v e r , i will d r a w the nega- tive c o n c l u s i o n t h a t t h e i d e a t h a t m a t h e m a t i c i a n s largely agree in their aesthetic j u d g e m e n t s is at best grossly oversimplified. sylvester described m a t h e - matics as t h e s t u d y of difference in similarity a n d simi- larity in difference. he w a s n o t characterising o n l y the mathematical intelligencer vol. , no. , mathematics. aesthetics has the same complexity, a n d b o t h perspectives require investigation. i will c o m m e n t o n s o m e possibilities for further re- search. h a r d y a s s e r t e d that a beautiful piece of mathe- matics s h o u l d d i s p l a y generality, u n e x p e c t e d n e s s , depth, inevitability, a n d economy. "inevitability" is p e r h a p s h a r d y ' s o w n idiosyncracy: it is n o t in other analyses i have come across. should it be? such lists, n o t linked to actual examples, perhaps r e p r e s e n t the m a x i m u m possible level of agreement, precisely because t h e y are so unspecific. at the level of this questionnaire, the variety of r e s p o n s e s suggests that individuals' interpretations of t h o s e generalities are quite varied. are t h e y ? h o w ? w h y ? h a l m o s ' s generality-specificity d i m e n s i o n m a y b e c o m p a r e d to this c o m m e n t b y saunders mac lane [ ]: "i a d o p t e d a s t a n d a r d p o s i t i o n - - y o u m u s t specify the subject of interest, set u p the n e e d e d axioms, and de- fine the terms of reference. atiyah m u c h preferred the style of the theoretical physicists. for t h e m , w h e n a n e w idea c o m e s u p , o n e d o e s not p a u s e to define it, b e c a u s e to do so w o u l d b e a damaging constraint. in- s t e a d t h e y talk a r o u n d a b o u t the idea, d e v e l o p its various connections, a n d finally come u p w i t h a m u c h m o r e supple a n d richer notion . . . . h o w e v e r i per- sisted in the position that as mathematicians w e m u s t k n o w w h e r e o f w e s p e a k . . . . this instance m a y serve to illustrate the p o i n t that there is n o w no a g r e e m e n t as to h o w to d o mathematics . . . . " a p a r t from a s k i n g - - w a s there ever?---such differ- ences in approach will almost certainly affect aesthetic j u d g e m e n t s ; m a n y o t h e r b r o a d d i f f e r e n c e s b e t w e e n mathematicians m a y h a v e the same effect. changes over time s e e m to be central for the indi- vidual a n d explain h o w one criterion can contradict another. surprise a n d m y s t e r y will b e s t r o n g e s t at the start. a n initial s o l u t i o n m a y i n t r o d u c e a d e g r e e of generality, depth, a n d simplicity, to be followed b y f u r t h e r q u e s t i o n s a n d f u r t h e r s o l u t i o n s , since t h e richest p r o b l e m s d o n o t reach a final state in their first incarnation. a n e w p o i n t of v i e w raises surprise anew, m u d d i e s the a p p a r e n t l y clear w a t e r s , a n d s u g g e s t s greater d e p t h or b r o a d e r generality. h o w d o aesthetic j u d g e m e n t s c h a n g e a n d d e v e l o p , in q u a n t i t y a n d quality, during this temporal roller coaster? poincar~ and v o n n e u m a n n , a m o n g others, have e m p h a s i s e d the role of aesthetic j u d g e m e n t as a heu- ristic aid in the process of mathematics, t h o u g h liable to mislead on occasion, like all such assistance. h o w d o individuals' j u d g e m e n t s aid t h e m in their work, at e v e r y level from preference for g e o m e t r y o v e r anal- ysis, or whatever, to the m o s t microscopic levels of mathematical thinking? mathematical aesthetics shares m u c h w i t h the aes- thetics of other subjects a n d n o t just the h a r d sciences. t h e r e is no space to d i s c u s s a variety of e x a m p l e s , t h o u g h i will m e n t i o n the related concepts of isomor- p h i s m a n d metaphor. h e r e is o n e v i e w of surprise [ ]: "fine writing, according to a d d i s o n , consists of senti- m e n t s w h i c h are natural, w i t h o u t being obvious . . . . o n the o t h e r hand, productions w h i c h are merely sur- prising, w i t h o u t b e i n g natural, can n e v e r give a n y lasting e n t e r t a i n m e n t to the m i n d . " h o w might "natural" b e interpreted in mathemat- ical terms? le lionnais u s e d the same w o r d . is it t r u t h that is b o t h natural and beautiful? h o w a b o u t h a r d y ' s "inevitable?" is n o t g r o u p t h e o r y an historically inevi- table d e v e l o p m e n t , and also natural, in the sense that g r o u p structures w e r e there to b e detected, sooner or later? is n o t the naturalness a n d b e a u t y of such struc- t u r e s r e l a t e d to d e p t h a n d t h e role of a b s t r a c t i o n , w h i c h p r o v i d e s a ground, as it were, against w h i c h the individuality of other less general mathematical entities is highlighted? mathematics, i a m sure, can only be m o s t d e e p l y u n d e r s t o o d in the context of all h u m a n life. in partic- ular, b e a u t y in mathematics m u s t be incorporated into a n y a d e q u a t e e p i s t e m o l o g y of mathematics. philoso- phies of mathematics that ignore b e a u t y will be inher- e n t l y d e f e c t i v e a n d i n c a p a b l e of e f f e c t i v e l y inter- preting t h e activities of mathematicians [ ]. r e f e r e n c e s . w. burnside, proceedings of the london mathematical so- ciety ( ), ( ), . . mr. davies, historical notices respecting an ancient problem, the mathematician ( ), . . t. dreyfus and t. eisenberg, on the aesthetics of mathe- matical thought, for the learning of mathematics ( ). see also the letter in the next issue and the author's reply. . freeman j. dyson, unfashionable pursuits, the mathe- matical intelligencer , no. ( ), . . p. r. halmos, why is a congress? the mathematical intel- ligencer , no. ( ), . . david hume, on simplicity and refinement in writing, selected english essays, w. peacock, (ed.) oxford: oxford university press ( ), . . f. le lionnais, beauty in mathematics, great currents of mathematical thought, (f. le lionnais, ed.), pinter and kline, trans. new york: dover, n.d. . . j. e. littlewood, a mathematician's miscellany, new york: methuen ( ), . . saunders mac lane, the health of mathematics, the mathematical intelligencer , no. ( ), . . roger penrose, the role of aesthetics in pure and ap- plied mathematical research, bulletin of the institute of mathematics and its applications ( ), . . ibid., . . david wells, beauty, mathematics, and philip kitcher, studies of meaning, language and change ( ). . david wells, mathematicians and dissidence, studies of meaning, language and change ( ). menelik road london nw rj england the mathematical intelligencer vol. , no. , a thing of beauty leading edge select a thing of beauty the mesmerizing patterns and brilliant colors found throughout the animal kingdom have long captivated scientists. research in species as diverse as birds, fish, and insects now addresses the fundamental question of how these remarkable displays are achieved, offering insights on co-opting already existing mechanisms and unexpected lessons for their evolution. distinctpigmentpatternsina silverlacedwyan- dotte chicken.image courtesy of d.andp. akers. cells of a feather flock together a unique feature of birds is their varied and colorful plumage, replete with striking patterns. by coupling a careful mapping of distinct feather features such as pigment color, distribution, and their temporal variation with a cellular and molec- ular analysis of melanocytes, cheng-ming chuong and colleagues provide a roadmap for studying feather patterning in chickens. notably, feather patterns arise through a combinatorial modulation of the presence, arrangement, and dif- ferentiation of melanocytes rather than through specific genetically encoded traits. one example of the power of such simple integrative changes is the striped plumage of barred plymouth rock chickens. in these birds, a previously identi- fied defect in the cdkn a/b tumor suppressor locus leads to a premature differ- entiation of melanocytes and a fluctuating loss of melanocyte progenitors, which, when coupled with the growth of feathers, creates the alternating black and white chevron-shaped pattern. in another example, the authors explored the temporal controlofpigmentpatterningintaiwancountrychickens,whosefeathersdisplay different colors from the distal tip to the proximal end. they find that temporal regulation of melanocyte progenitor activity during the creation of the distinct parts of a feather accounts for the color transitions. a third modulator, conferring laced-edge feathers to silver laced wyandotte chickens turns out to be the pulp adjacent to melanocytes, expressing a pigment modifier. therefore, co-opting simple cellular functions affecting the topology of the melanocyte progenitor niche isan effectivemechanismfor creating complexpatterns that ultimately impactanimalbehavior. lin, s.j., et al. ( ). science , . wild-type and bnc mutant zebrafish. image courtesy of l. patterson and d. parichy. how the (zebra)fish got its stripes cells conferring iridescence are at the focus of two recent papers investigating stripe formation in zebrafish. pigment patterns in fish have important functions in mate choice, shoaling, and avoiding predators and have been used to study the mechanisms underlying morphological development and evolution. several pigment cells contribute to the striped patterns decorating the flanks of zebrafish: black melanophores, yellow or orange xanthophores, and iridescent iridophores. dark stripes of melanophores alternate with light stripes of xantho- phores, whereas iridophores convey a luminescent appearance overall. the mechanisms of stripe formation have been under scrutiny, and previous studies have shown the importance of interactions between melanophores and xantho- phores. however, the contribution of iridophores to pattern development has not been known. david parichy’s and christiane nüsslein-volhard’s groups now show that iridophores do more than convey a shiny look; their presence is necessary for organizing both melanophores and xanthophores. both papers provide evidence that normal stripe formation cannot occur in the absence of iridophores and show that iridophores both promote and inhibit melanophore and xanthophore development over different spatial scales. parichy and colleagues also go a step further in identifying molecular mechanisms underlying stripe formation. they show that a highly conserved zinc finger protein, basonuclin- (bnc ), acting in the tissue environment to promote the development of all three pigment cell classes, does so in part by regulating expression of the growth factors kit ligand a (kitlga) and colony stimulating factor- (csf ), required by melanophores and xanthophores, respectively. they also demonstrate that once bnc -dependent iridophores appear, iridophores themselves express csf and thereby specify where xanthophores will develop. these findings demonstrate novel pigment cell autonomous interactions in pattern formation as well as the importance of nonautonomous spatial cues in designating where stripes will form. patterson, l.b., et al. ( ). plos genetics. published online may , . http://dx.doi.org/ . /journal.pgen. . frohnhöfer, h.g., et al. ( ). development , – . cell , august , ª elsevier inc. http://dx.doi.org/ . /journal.pgen. http://dx.doi.org/ . /journal.pgen. wing pigmentation pattern diversity among drosophila species. image courtesy of b. prud’homme and n. gompel. these mechanisms are spot on in the insect world, diverse pigmentation patterns on the wings and cuticles have evolved in response to the pressures of predation, geographical adapta- tion, and mate preference. seeking to understand the mechanisms of diversifi- cation among species has been a longstanding quest. in a recent report, benjamin prud’homme, nicolas gompel, and colleagues powerfully employ the tools of genetics to study the basis of spot formation on drosophila wings. they examined the expression pattern of a pigment gene yellow, which confers some of the characteristic wing markings, and sought to identify the transcrip- tion factor regulating its distribution. they find that distalless (dll), a transcrip- tion factor with an essential, well-characterized role in wing formation, fulfills this role. after its function in wing formation is over, dll switches its expression pattern to specifically drive the placement of the pigment markings. strikingly, dll expression diverges among species of flies to drive the differential place- ment of pigment spots on the wing. this work illustrates how a gene with an essential function and the ability to control multiple downstream targets can be co-opted to modify traits among different species. in addition to the formation of sequential orange spots in a caterpillar of swallowtail butterfly, papilio machaon. image courtesy of h. fujiwara. markings, some species also have to contend with their maintenance. in the case of caterpillars, markings on their cuticles need to be restored after each molt. the molecular pathways involved in this periodic upkeep are the focus of the work by haruhiko fujiwara and colleagues. analysis of a silkworm mutant caterpillar with twin-spots on the dorsal side of multiple sequential segments reveals that a cis-regulatory change in wnt expression in the epidermis is responsible for spot patterning. moreover, periodic upregulation of wnt within the spot marking area is associated with the presence of a molting hormone. transgenic expression of ectopic wnt induces additional pigmentation, providing further evidence that wnt expression may confer the diversity of spot patterns found in the insect world. indeed, this mechanism of spot formation maintenance is conserved among other lepidopteran species. arnoult, l., et al. ( ). science , . yamaguchi, j., et al. ( ) nat. commun. published online may , . http://dx.doi.org/ . /ncomms . mirna kvajo cell , august , ª elsevier inc. http://dx.doi.org/ . /ncomms a thing of beauty the beauty and the beast: aspects of the autonomic nervous system - / . © int. union physiol. sci./am.physiol. soc. news physiol. sci. • volume • june there are different methods to assess sympathetic nervoussystem (sns) effects on the cardiovascular system in humans. besides the assessment of endorgan responses such as blood pressure and heart rate, the most widely used meas- urements are plasma-norepinephrine (ne) assay, ne spillover technique, microneurographic recordings of postganglionic muscle and skin sympathetic nerves, and power spectrum analysis of blood pressure and heart rate variability. the tech- nique of microneurography allows a direct and continuous assessment of sns activity ( , ) and represents the only measure to detect small and short-lasting changes within the system. superficial nerves such as the peroneal nerve are par- ticularly suitable for microneurography since their anatomic location allows the placement of a recording microelectrode. sympathetic outflow is regulated in the brain stem and the medulla oblongata. sympathetic nerves travel along the nerve column into ganglia, in which acetylcholine is respon- sible for transmission of activity from the pre- to the postgan- glionic adrenergic neurons innervating the heart and many other organs of the body. depolarization of postganglionic sympathetic nerve fibers leads to increases in intracellular calcium in adrenergic nerve endings where ne is released the beauty and the beast: aspects of the autonomic nervous system roberto corti, christian binggeli, isabella sudano, lukas e. spieker, rené r. wenzel, thomas f. lüscher, and georg noll sympathetic nerve activity is altered and is a prognostic factor for many cardiovascular diseases such as hypertension, coronary syndromes, and congestive heart failure. therefore, the selection of vasoactive drugs for the treatment of these diseases should also take into consideration their effects on the sympathetic nervous system. r. corti, c. binggeli, i. sudano, l. e. spieker, r. r. wenzel, t. f. lüscher, and g. noll are in the department of cardiology, university hospital zurich, switzerland. within the next decade. however, it is equally true that an enormous amount of research is still to be done before human therapy can be attempted. an essential side effect of develop- ing therapies in animal models will be a further understand- ing of retinal cell and molecular biology. for example, what is/are the role(s) of c-fos, does photoregeneration of rhodopsin by blue light occur under natural conditions in mammals, and do autophagy, the proteasome system, and apoptosis repre- sent means of adaptation to changing metabolic and environ- mental conditions? in this latter context, the apparent paradox of light eliminating photoreceptors might be resolved into a meaningful measure in those cases in which adaptation to bright light is required. the death of single cells might help the remaining ones to survive through the reduction of overall light sensitivity or photon absorption, respectively. we are supported by the swiss national science foundation, brupbacher foundation zürich, emdo- and hartmann müller-foundation, zürich, suva-research foundation, luzern, switzerland, grimmke-foundation, düsseldorf, germany, and others. references . enari, m., h. sakahira, h. yokoyama, k. okawa, a. iwamatsu, and s. nagata. a caspase-activated dnase that degrades dna during apoptosis, and its inhibitor icad. nature : – , . . häcker, g., and d. l. vaux. a chronology of cell death. apoptosis : – , . . hafezi, f., j. p. steinbach, a. marti, k. munz, z. q.wang, e. f. wagner, a. aguzzi, and c. e. remé. the absence of c-fos prevents light-induced apop- totic cell death of photoreceptors in retinal degeneration in vivo. nat. med. : – , . . hafezi, f., m. abegg, c. grimm, a. wenzel, k. munz, j. stürmer, d. b. far- ber, and c. e. remé. retinal degeneration in the rd mouse in the absence of c-fos. invest. ophthalmol. vis. sci. : – , . . mancini, m., d. w. nicholson, s. roy, n. a. thornberry, e. p. peterson, l. a. casciola-rosen, and a. rosen. the caspase- precursor has a cytosolic and mitochondrial distribution: implications for apoptotic signaling. j. cell. biol. : – , . . miller, l. j., and j. marx. apoptosis. science : – , . . nir, i., and n. agarwal. diurnal expression of c-fos in the mouse retina. brain res mol brain res : – , . . portera cailliau, c., c. h. sung, j. nathans, and r. adler. apoptotic pho- toreceptor cell death in mouse models of retinitis pigmentosa. proc. natl. acad. sci. usa : – , . . raff, m. c., b. a. barres, j. f. burne, h. s. coles, y. ishizaki, and m. d. jacobson. programmed cell death and the control of cell survival: lessons from the nervous system. science : – , . . remé, c. e., c. grimm, f. hafezi, a. marti, and a. wenzel. apoptotic cell death in retinal degenerations. prog. retin. eye res. : – , . . remé, c. e., f. hafezi, a. marti, k. munz, and j. j. reinboth. light dam- age to retina and pigment epithelium. in: the retinal pigment epithelium, current aspects of function and disease, edited by m. f. marmor and t. j. wolfensberger. oxford, uk: oxford university press, . . rich, k. a., y. zhan, and j. c. blanks. aberrant expression of c-fos accom- panies photoreceptor cell death in the rd mouse. j. neurobiol. : – , . . susin, s. a., n. zamzami, and g. kroemer. mitochondria as regulators of apoptosis: doubt no more. biochim. biophys. acta : – , . . yoshida, k., k. kawamura, and j. imaki. differential expression of c-fos mrna in rat retinal cells: regulation by light/dark cycle. neuron : – , . . zhao, j., q. zhou, t. wiedmer, and p. j. sims. level of expression of phos- pholipid scramblase regulates movement of phosphatidylserine to the cell surface. j. biol. chem. : – , . downloaded from journals.physiology.org/journal/physiologyonline at carnegie mellon univ ( . . . ) on april , . from vesicles located in the nerve terminals. ne is the main neurotransmitter, although neuropeptide y and atp may also participate. the amount of ne and other neurotransmitters released is tightly regulated by negative feedback mecha- nisms involving the neurotransmitter itself (via presynaptic α -adrenergic receptors), but also other mediators such as adrenaline, serotonin, histamine, acetylcholine, and many others (fig. ) ( ). the effects of ne at the postjunctional level, i.e., vascular smooth muscle cells of blood vessels and myocytes of the myocardium, involve β-adrenergic receptors, as well as α - and α -adrenergic receptors. the former are involved in vasodi- latation (β -adrenergic receptors), inotropy, and chronotropy (β -adrenergic receptors), and the latter mediate vasocon- striction of the blood vessel wall. of particular interest is the fact that sns activity is very heterogeneous in the body. indeed, the system is capable of activating certain organs but not others, depending on the pattern of activation and the physiological stimulus involved. sympathetic fibers in the peroneal nerve innervate blood ves- sels in muscle tissue or the skin of the leg. electrical activity within muscle and skin sympathetic nerve fibers can be iden- tified according to its characteristic pattern. the neurogram of muscle sympathetic activity (msa), which significantly con- tributes to the regulation of peripheral vascular resistance, reveals spontaneous, intermittent, pulse-synchronous sympa- thetic bursts that increase during apnea. msa can be stimu- lated by different maneuvers such as physical activity, mental stress, hypoxia, and unloading baroreceptors. during a cold pressor test, a massive increase in msa occurs ( , ). sns and cardiovascular disease the sympathetic nerve fibers are ubiquitously distributed within the heart, the blood vessels, the kidney, and major peripheral baroreceptor sites, a finding that suggests a direct effect on fluid control, cardiac output, and peripheral vascu- lar resistances. in fact, sns significantly regulates cardiovas- cular homeostasis ( ), and sns activity is altered in various forms of cardiovascular disease. activation of the sns plays an important role in the pathophysiology and the prognosis of cardiovascular disease such as hypertension, ischemic heart disease, and heart failure. hypertension. in hypertension, hyperactivity of the sns was postulated decades ago. it has been demonstrated that, partic- ularly in the early phases of the hypertensive process, the sym- pathetic drive is increased. in patients with borderline or mild hypertension, increased cardiac β-adrenergic and vascular α- adrenergic drive has been documented by selective receptor blockade. the evidence from pharmacological studies is in line with the slightly increased plasma levels of ne in young sub- jects with mild hypertension. these findings were confirmed by experiments that showed an increase of ne spillover in the heart and the kidney of hypertensives in particular. further- more, using the technique of microneurography it has been clearly demonstrated that resting msa is increased in patients with borderline hypertension ( ). in addition, an exaggerated blood pressure response to mental stress has been demon- strated in patients with essential hypertension. in normotensive offspring of hypertensive parents, we found that the msa response to mental stress is more pronounced than in offspring news physiol. sci. • volume • june figure . regulation of vascular smooth muscle cell tone by sympathetic nervous system (sns). release of neurotransmitters, norepinephrine (ne), neuropep- tide y (npy), and atp at sympathetic nerve endings is influenced by several substances acting on presynaptic receptors. thus acetylcholine (ach), histamine, sero- tonin ( -ht), and dopamine can inhibit (–) release of ne. ne itself can inhibit its release by acting on presynaptic α -receptors. vasoactive substances such as epi- nephrine and angiotensin ii can increase (+) release of ne by activating presynaptic receptors. on smooth muscle cells, ne can stimulate α -receptors, causing contraction, and α -receptors, causing relaxation; atp acting on p receptors induces relaxation, whereas npy can induce constriction. downloaded from journals.physiology.org/journal/physiologyonline at carnegie mellon univ ( . . . ) on april , . of normotensive parents, but resting msa is comparable (fig. ) ( ). thus it is now clear that in offspring of hypertensive par- ents in which resting blood pressure is still normal, msa is abnormally stimulated during mental stress ( ). it is possible that early on in the disease process the sns is only activated abnormally during episodes of increased stress and that resting msa is increased during development of high blood pressure, whereas at later stages of hypertension sns activity may again become normal, although the values may still be too high for the level of blood pressure of these patients. coronary artery disease. in patients with coronary artery disease, the sns and its activity may be important as triggers for acute coronary syndromes in general and sudden death in particular. indeed, abnormal sns activity as assessed by heart rate variability greatly determines prognosis in patients after myocardial infarction ( ). heart failure. in heart failure, the sns is markedly activated ( , ), probably because of an activation of baroreflex mech- anisms to compensate for low blood pressure and decreased perfusion of vital organs as a consequence of abnormal left ventricular function. this activation of sns may initially lead to an increase in cardiac output, but in severe heart failure sns-mediated increase in peripheral vascular resistance fur- ther deteriorates cardiac function and may actually be harm- ful. in the vasodialator-heart failure trial study, patients with the highest levels of plasma ne had the poorest prognosis ( ). this suggests that indeed in heart failure the degree of acti- vation of the sns may be an important prognostic variable. modulation of sympathetic nerve activity by cardiovascular drugs the efficacy of cardiovascular drugs primarily depends on their action on blood vessel wall and myocardium. however, some of the beneficial effects of the drugs in the circulation, i.e., vasodilatation and stimulation of myocardial contractil- ity, may be overcome at least in part by their effects on neu- rohumoral regulators. various drugs are used to treat patients with cardiovascu- lar disease, e.g. β-blockers, calcium antagonists, ace- inhibitors, and nitrates. indeed, certain drugs may be very efficacious antihypertensive or vasodilator agents yet activate the sns, and others inhibit it ( ). given the important prog- nostic relevance of sns activity in patients with cardiovascu- lar disease, understanding the effects of these vasoactive drugs on the sns may have great clinical relevance. calcium channel blockers are potent vasodilators acting directly on vascular smooth muscle cells. these drugs are widely used for the treatment of hypertension and angina pectoris. in secondary prevention after myocardial infarction, calcium antagonists did not have beneficial effects on car- diovascular events and survival, particularly in patients with heart failure. this could be due to either negative inotropic effects or a baroreceptor-mediated activation of the sns ( ). dihydropyridines such as nifedipine also have important effects on the sns in healthy human subjects. oral adminis- tration of short-acting nifedipine leads to a marked increase of msa and ne plasma levels (fig. ). the degree of activa- tion of msa is comparable to a cold pressor test (which is the most potent stimulus of sympathetic nerve activity). most interestingly, nifedipine remains a very important stimulus for sns activity even in the presence of a cold pressor test ( ). this finding indicates that with short-acting dihydropy- ridines, the peripheral and cardiac portions of the sns are highly activated and remain responsive to these stimulatory maneuvers. indeed, the potent vasodilator effects under acute conditions together with the negative inotropic effects of the drug may lead to marked activation of the baroreflex news physiol. sci. • volume • june figure . muscle sympathetic activity (msa) in peroneal nerve at rest and during mental stress in normotensive offspring of normotensive (left) and hypertensive (right) parents. increase of msa during mental stress is more pronounced in offspring of hypertensive parents. bp, blood pressure; hr, heart rate. modified from ref. . downloaded from journals.physiology.org/journal/physiologyonline at carnegie mellon univ ( . . . ) on april , . and in turn an increase in heart rate and sns activity. it is conceivable that such effects are less pronounced with a more slowly acting form of nifedipine. the nifedipine gas- trointestinal therapeutic system (gits), which is a slow- release form of nifedipine, indeed does not significantly change heart rate even under acute conditions, suggesting that the baroreflex is less activated. however, in the per- oneal nerve, a marked activation of msa can still be docu- mented (fig. ) ( ). this suggests that a slower onset of vasodilatation as it occurs with slow-release nifedipine does not lead to a generalized sympathetic nerve activation and does not significantly increase sympathetic outflow to the heart. nevertheless, sympathetic outflow to peripheral mus- cles is still activated under these conditions. whether such effects also occur during chronic treatment with nifedipine remains to be demonstrated. due to its different pharmacological profile, verapamil is associated with a decrease rather than an increase in heart rate even under acute conditions. during chronic therapy in patients with hypertension, verapamil lowers rather than increases plasma ne. although studies with microneurography have not been performed yet, there is indirect evidence that verapamil affects the sns differently from dihydropyridines ( ). angiotensin-converting enzyme (ace) inhibitors also act as vasodilators, inhibiting the formation of the vasoconstrictor peptide angiotensin ii. ace inhibitors tend to lower heart rate in normotensive subjects, although they do slightly decrease blood pressure. these drugs not only improve symptoms in patients with left ventricular dysfunction and/or congestive heart failure but also reduce acute coronary events and death. experimentally, angiotensin ii stimulates sns activity by activating specific binding sites in the brainstem and, at presynaptic levels, it increases the release of ne from sym- pathetic nerve endings (fig. ). these mechanisms could explain the increased msa observed in patients with reno- vascular hypertension, characterized by a high plasma level of angiotensin ii. after administration of captopril in healthy volunteers, msa remained constant despite a significant decrease in diastolic blood pressure (fig. ) ( ). these find- ings are in line with the observation that in rat model of renal hypertension lisinopril and losartan had no influence on splanchnic sympathetic nerve activity despite a reduction in blood pressure. this effect on sns activity could explain the favorable effects of ace inhibitors on the prognosis of patients with heart failure in whom activation of the sns is an important prognostic factor. hence, ace inhibitors and possibly angiotensin ii receptor antagonists may be particu- larly efficacious in blunting or even inhibiting the untoward effects of the sns in patients with cardiovascular disease. similar reduction of blood pressure is achieved with nitrates, but these drugs are associated with marked activa- tion of the sns. earlier studies demonstrated that intravenous administration of nitrovasodialators is associated with a marked increase in msa. in healthy subjects, an acute oral administration of isosorbide dinitrate causes a marked increase in msa (fig. ) and heart rate and has little effect on blood pressure. indeed, this effect of the nitrates may be partially responsible for the clinically observed tolerance, or rather pseudotolerance, since the baroreflex-mediated news physiol. sci. • volume • june figure . msa expressed as bursts/min (left) and heart rate (right) before and after oral nifedipine [ mg, mg, and gi theraputic system (gits) of mg] or placebo. bpm, beats per minute. modified from ref. . figure . change in resting msa minutes after oral administration of placebo, . mg captopril, and mg isosorbide dinitrate (isdn). a signifi- cant increase in msa was observed in subjects who received placebo. increase in msa after isdn was more pronounced compared with placebo. in subjects treated with captopril, msa did not change. *p < . vs. placebo; #p < . vs. isdn. modified from ref. . downloaded from journals.physiology.org/journal/physiologyonline at carnegie mellon univ ( . . . ) on april , . news physiol. sci. • volume • june activation of the sns in part blunts the vasodilator effects of these drugs in the intact organ ( ). centrally acting drugs, i.e., clonidine and α-methyl-dopa, have been used for the treatment of hypertension for a long time. it has been postulated that this antihypertensive effect is due to a central inhibitory effect on the sns. moxonidine belongs to a new generation of centrally acting drugs that activate i -imida- zoline receptors in the brain stem. the oral administration of moxonidine in healthy volunteers and hypertensive patients leads to a significant decrease of systolic and diastolic blood pressure, ne, and msa ( ). this demonstrates that the i -imida- zoline receptor agonist moxonidine reduces blood pressure in untreated hypertensive subjects through the reduction in central sympathetic outflow ( ). this effect may be beneficial not only in hypertensives but also in patients with heart failure. clinical implications in conclusion, it is clear that sympathetic activity is an important prognostic factor in patients with cardiovascular disease and in heart failure in particular. its true importance, however, has been revealed more recently though new tech- niques allowing precise assessment of its activity and its con- trol over cardiovascular functions in the intact organism. recent data suggest that activation of the sns during men- tal stress may precede the increase in resting activity present in early stages of hypertension. these data suggest that respon- siveness as well as activity of the sns may play an important role in the development of hypertension. hence, the effects of drugs on this important regulatory system should be more thoroughly investigated since this may have important impli- cations for the effects on the prognosis of these patients. in regard to calcium antagonists, it appears that the effects of cal- cium antagonists on sns activity depend on pharmacokinet- ics of these drugs as well as their genuine pharmacological properties. activation of the sns is most pronounced with short-acting dihydropyridines and less so with long-acting preparations of these drugs. these properties of certain cal- cium antagonists deserve further investigation to elucidate their clinical implications. ace inhibitors, besides their favor- able influence on hemodynamics, seem to lower sns activity, an effect that may contribute to the beneficial effects on the prognosis of patients with impaired left ventricular function. assessment of the influence of pharmacotherapy on the sns by sensitive techniques may allow the tailoring of drug treat- ment for different patient populations in the future. georg noll was awarded the pfizer research prize for clinical cardiovas- cular research in for the work reviewed in this article. references . anderson, e. a., c. a. sinkey, w. j. lawton, and a. l. mark. 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receptors and the endothelium. in: handbook of hypertension, vol. , physiology and pathophysiology of hyperten- sion—regulatory mechanisms, edited by r. c. tarazini and a. zanchetti. amsterdam, the netherlands: elsevier, , p. – . . wallin, b. g. intraneural recordings of normal and abnormal sympathetic activity in man. in: autonomic failure, edited by s. r. bannister. oxford, uk: oxford university press, , p. – . . wenzel, r. r., g. allegranza, c. binggeli, s. shaw, p. weidmann, t. f. lüscher, and g. noll. differential activation of cardiac and peripheral sns by nifedipine: role of pharmacokinetics. j. am. coll. cardiol. : – , . . wenzel, r. r., l. spieker, s. qui, s. shaw, t. f. lüscher, and g. noll. the i -imidazoline receptor agonist moxonidine decreases sympathetic nerve activity and blood pressure in hypertensives. hypertension : – , . in forthcoming issue toward understanding the role of methylation in aldosterone-sensitive na+ transport james d. stockand, robert s. edinger, douglas c. eaton, and john p. johnson ca +-activated cl– channels: a newly emerging anion transport family catherine m. fuller and dale j. benos angiotensin ii receptor physiology using gene targeting michael i. oliverio and thomas m. coffman downloaded from journals.physiology.org/journal/physiologyonline at carnegie mellon univ ( . . . ) on april , . on the meaning of natural beauty in landscape legislation this is a repository copy of on the meaning of natural beauty in landscape legislation. white rose research online url for this paper: http://eprints.whiterose.ac.uk/ / article: selman, paul and swanwick, carys ( ) on the meaning of natural beauty in landscape legislation. landscape research, ( ). p. . issn - https://doi.org/ . / eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ reuse unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. the copyright exception in section of the copyright, designs and patents act allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. the publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the white rose research online record for this item. where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher’s website. takedown if you consider content in white rose research online to be in breach of uk law, please notify us by emailing eprints@whiterose.ac.uk including the url of the record and the reason for the withdrawal request. mailto:eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ this is a post-peer-review draft, prior to publisher formatting selman, p h and swanwick, c a ( ) on the meaning of natural beauty in landscape legislation. landscape research, vol. , no. , – . doi : . / on t he meaning of nat ural beauty in landscape legislat ion paul selman and carys swanwick department of landscape, university of sheffield abstract the term ‘natural beauty’ has been an important criterion for designating and managing fine landscapes in the uk and elsewhere. however, its meaning has been assumed to be self- evident and has never been officially defined. latterly, this has become problematic in relation to more critical contemporary understandings of ‘natural’, and legal challenges to the use of the term in practice. based on an analysis of the antecedents to legislation for the protection of natural beauty, and of subsequent efforts to analyse and describe fine landscapes, this paper considers the contested use of ‘natural beauty’ in current landscape policy. i t proposes an extended meaning for the term which is consistent with the intentions of the original legislators. keywords: natural beauty protected landscapes landscape character national parks landscape legislation i ntroduction the concept of natural beauty is one of the cornerstones of legislation to protect landscapes in the uk. the term “natural beauty” has existed formally in legislation for england and wales since the national parks and access to the countryside act, and has parallels in the northern i reland amenity lands act and nature conservation and amenity lands order, whilst the natural heritage (scotland) act includes “natural beauty and amenity” within its definition of natural heritage. the significance of the concept extends well beyond the uk, and has more general implications for ‘protected areas’ which fall into i ucn category v protected landscapes/ seascapesi , and which are predominantly ‘cultural’ rather than ‘natural’. the beauty of such places cannot be natural in the strict sense, and this paper explores the current meaning and use of the term in relation to the designation and management of protected cultural landscapes. the review of the national park authorities in wales commentedii that "the breadth of the term 'natural beauty'…. is not well understood by all those who take decisions affecting national parks.” as a result the welsh assembly, in its national park review action plan, asked the countryside council for wales (ccw) to produce a statement on the full scope of 'natural beauty'. this paper arises from research undertaken for the countryside council for wales to produce such a statement. although the term ‘natural beauty’ initially seems uncontroversial, in practice it has had to serve as a vehicle for successive trends in landscape planning, and its implicit meanings have been stretched to the point where its continued policy and legal fitness is questionable. equally, however, it is associated with much policy and legal precedent, and is a widely used and familiar phrase without an obvious alternative. i n order to explore its continued suitability as a basis for planning fine landscapes, this paper examines it from four perspectives. first, we consider the theories and concepts which have underpinned natural beauty, ranging from aesthetic arguments to more utilitarian justifications. second, we explore the origins of natural beauty as an official term, noting the evolution from high culture, preservationist discourses to more instrumental arguments about town planning and nature conservation, and from which ‘natural beauty’ eventually prevailed amongst legislators as the preferred shorthand expression. third, we identify how the term evolved during the latter half of the th century, as advances in landscape planning required a fuller articulation of the qualities that were to be protected or enhanced within fine landscapes. we also consider the sifting of the term in public inquiries, noting in particular its contested meanings between different parties. finally, we report on a stakeholder consultation which debated the continuing value of the term as an axiom of landscape protection, management and planning. at present, the uk is heavily relying on ‘natural beauty’ legislation as a basis for complying with the european landscape conventioniii , stretching its original intentions yet further. i t is clear that natural beauty is a dynamic and malleable concept, potentially posing problems for consistency of interpretation, and yet apparently retaining a continuing relevance. concept s and theories underpinning natural beaut y whilst there is little scholarly literature on natural beauty per se, cognate landscape topics are well represented in the literature, reflecting a long-standing interest in the nature of aesthetics and the inspirational qualities of beautiful countryside. the body of theory on aesthetics relates to several categories of object including the natural environment, whilst there have been extensive debates about closely related concepts such as ‘sublime’, ‘picturesque’ and ‘wilderness’. latterly, many researchers have investigated links between the landscape and human wellbeing. all of these offer some convergent ideas, although their differences create problems in agreeing a durable definition of natural beauty. perhaps the most fundamental difficulty in interpreting natural beauty is that the term appears generally to have been assumed, by its originators, to be obvious and self-explanatory. however, as appletoniv has observed, the discussion of natural beauty is often discipline specific and highly subjective. for example, within philosophy (particularly the study of aesthetics), the early th century debate led by shaftesburyv and burkevi centred on the distinction between beauty and the sublime. these two notions were deemed opposite ends of the emotion spectrum – sublime being related to vistas that evoked reverence, fear and horror, and beauty being associated with feelings of pleasure from gazing on a smooth, delicate and lovely scene. both beauty and the sublime provoked a passion related to the view, although they were difficult to reconcile as one was founded on pleasure and the other on pain. the literature and fine art of the romantic movement – for example, writers such as gilpinvii and priceviii - introduced a category of ‘picturesque’, which was used to describe a scene that was not delicate and smooth but had interesting sharp angles, variety and, often, ruins as an allusion to human ‘fall’ and the capacity of nature to regain ownership of a landscape. wordsworth’s guide to the lakes published in reflected these picturesque sentiments in chapters on the forms and colourings of natural features, and charms and character evolved from human inhabitationix. this predominantly european standpoint contrasted with the “wilderness concept” that emerged in response to the exploration of northern america and the new world in the th century. reports of the scenery were in no way romantic or picturesque and wilderness encapsulated areas with a primeval character and minimal anthropogenic influencex . the observer was still interested in the aesthetics of the scene but perhaps more so in the transcendental experiences and spiritual feelings it evinced. other writers have looked more synoptically at the properties of beauty, and provide insight into its defining attributes. for example, in the th century, hogarth’sxi analysis was instrumental in addressing the problem of pure subjectivity, arguing that beauty should be related to principles of fitness, variety, uniformity, simplicity, intricacy and quantity. bellxii draws attention to the contributions of schopenhauer – who suggested that natural beauty relates to the spirit of the place (genius loci) where distinct features fit together well – and whitehead – whose analysis of aesthetics incorporated ‘massiveness’ (variety of detail with effective contrast) and ‘intensity proper’ (magnitude and scale). more recently, carlsonxiii has sought to explain aesthetic experience of landscape in terms of both multisensory ‘engagement’ and ‘cognitive’ understanding of its nature, potentially leading to preferences for landscapes where there appears to be a ‘functional fit’ between human interventions and the natural environment. the study of aesthetics, in which the response is perceptual rather than rational and factual, and where the observer passively viewed the landscape and judged its looks according to contemporary rules, prompts a subjectivist paradigm in which the beholder rather than the object determines the aesthetic. as noted, this view dominated before and during the th century, and lothianxiv argues that it has a continuing relevance to landscape appreciation. buddxv and bradyxvi have considered aesthetics in relation to ‘nature’ and the environment, and they concentrate principally on providing a critical understanding of what aesthetic appreciation of nature involves. whilst neither sheds particular light specifically on what might be meant by the ‘natural beauty’ of the countryside, bradyxvii does assemble categories of aesthetic qualities (such as ‘sensory’ and ‘symbolic’) which have distinct resonance with the properties frequently ascribed to human reactions to landscapes. during the past twenty years or so, there has been an empirical trend towards demonstrating how (positive) landscape attributes are linked to human preference and wellbeing. whilst these are separate issues – the former relating to aesthetic appreciation based on recordable features and the latter providing a more instrumental justification for landscape interventions – they overlap extensively in practice. for example, many papers describe how research participants consistently choose natural or semi-natural landscapes relative to those with many urban features (van den berg et al xviii; herzog et al xxiii xix; staats et alxx; and ulrichxxi). kaplanxxii asked a large sample of residents what visual preferences they had from their windows and those with numerous natural elements such as trees and flowers reported tranquillity, peace and more positive thinking. williams and harvey describe the transcendent experiences amongst a group of visitors to a forest, notably, feelings of the sublime, individual insignificance, awe and relaxation. fredrickson and andersonxxiv analysed the accounts of female trekkers’ experiences of the grand canyon and northern minnesota, and recorded diverse emotions from a sense of infinitude to renewal of strength and capability. real et alxxv related expressed landscape preferences to models of human behaviour, particularly those based on psychophysical and cognitive paradigms, and also confirmed that natural beauty may have demonstrable positive effects on physical and mental wellbeing. ulrich et al xxvii xxviii xxxii xxvi investigated the effect of showing volunteers a distressing film and then following this with a film of an urban scene or a film of the natural environment. they found that both psychological and physical signs of stress reduced quickly and effectively when people looked at a scene of trees, lakes or meadows. similar experiments were carried out by van den berg et al , herzog et al and purcell et al , with comparable results. staats and hertig confirmed the restorative effects of group and solitary landscape experiences, whilst mitchell and pophamxxix have shown that exposure to green environments can significantly mitigate socioeconomic health inequalities. harmonxxx proposes that appreciation of natural beauty is basic to human nature, and thus has therapeutic and enriching effects on intellectual, psychological, emotional, spiritual, cultural and creative faculties. martinezxxxi illustrates how ancient languages define landscape and wilderness as etymologically linked to terms for health, wholeness and liveliness. thus, landscape beauty may have a “restorative” effect – for instance, fredrickson and anderson consider how beauty can provide personal benefits such as improved health, psychological well-being and an improved self image. similarly, williams and harveyxxxiii xxxiv identify ‘psychodynamic’ properties where people derive spiritual power from natural features and a sense of place and familiarity with a favourite spot, often combined with the performance of activities and rituals in beautiful areas that have personal meaning. purcell et al suggest seven categories of psychologically restorative landscape values, namely, ‘being away’, ‘coherence’, ‘compatibility’, ‘fascination’, ‘scope’, ‘familiarity’ and ‘preference’. i nterestingly, whilst these may occur in isolation, they often occur in combination in areas deemed to possess natural beauty. there is a further argument over whether certain landscape types are intrinsically capable of evoking ‘positive’ responses in the beholder as a result of our evolution in particular environmental settings, or whether these reactions are merely culturally determined. notably, some researchers have argued for a systematic, cross-cultural preference for landscapes that evoke our evolutionary cradle, the african savannah. thus, appleton xxxvi. oriansxxxvii xxxviii xxxix xxxv has famously related the attractiveness of landscapes to their opportunities for providing ‘prospect and refuge’, whilst kaplan has linked preference to properties such as complexity, coherence, mystery and legibility proposed that a range of patterns, rather than individual features, were more likely to determine perceived landscape beauty. the line of enquiry that relates preference to biology and evolution is closely associated with theories of biophilia (innate affinities between people and nature), and topophilia (between people and place, including the cultural landscape). whilst not necessarily undermining the statistical and deterministic basis of landscape preference, it is clear that societies and cultures do vary in their assessment of the relative beauty of different landscapes. botkinxl has identified discernible changes in what people believe to be attractive over time; when confronted with natural beauty, people have also revealed their artistic sensitivity and educational background. i n a similar vein, ribexli found systematic differences between people who innately favour protected landscapes and those who see land as a basis for production. hence, parsons and daniel xliii xlii emphasise how scenic aesthetics can be considered superficial and socially malleable, suggesting that acquired characteristics rather than inherited ones are pre-eminent. i t is also interesting to speculate, particularly in the light of current policy imperatives for a more ‘inclusive’ basis to countryside enjoyment, that ethnicity may also influence preference – e.g. purcell et al’s finding that australian interviewees ranked certain hillside landscape adversely because of their cultural association with depressed rural areas, yang and brown’sxliv evidence on preferential enjoyment of the japanese landscape, kohasaka and flitner’sxlv evidence on nationally variable perceptions of economic or romantic qualities attached to wooded landscapes, and zube and pitt’sxlvi findings regarding differential preferences for anthropogenically influenced landscapes between american ethnic groups. i n summary, therefore, it is clear that natural beauty is far from the straightforward term suggested by the legislation, lacking a precise definition or defining set of attributes. i ndeed, there are sharp differences between sublime, picturesque or ‘wilderness’ landscapes, all of which could be deemed by some observers to epitomise natural beauty. nevertheless, there is a strong case that beauty is explicable in terms of theories of aesthetics, and that the ‘natural’ world can comprise a distinct category of the ‘aesthetic’. further, there appear to be recurrent terms which are applicable to beautiful landscapes; these properties appear to be widely appreciated, both consciously and subliminally, in ways that may be experimentally confirmed. equally, there is a probably unresolvable debate about the relative significance of biology and culture, but both are clearly important. the influence of culture means that natural beauty will inevitably be a dynamic concept, related to a prevailing consensus on what people consider to be aesthetic and important to human wellbeing. yet it is not entirely fluid, and many qualities appear to be consistently recognised across time and place. we now turn to the ways in which natural beauty has been interpreted officially, before offering our own distillation. recognising that natural beauty is a complex notion, we examine how it became adopted as a simple legal phrase fit to cover a variety of situations. the origins of “natural beauty” as an official term i n england and wales, the watershed legislation which enshrined the concept of ‘natural beauty’ was the national parks and access to the countryside act , which emerged following half a century of debate, lobbying and examination by official government committees. the antecedents go back much further and the term grew out of a rich tradition of appreciating the natural realm from an aesthetic point of view and promoting its protection. whilst the attempts during the th century to search for an all embracing theory of landscape beauty are now recognised as somewhat crude and pompous, appletonxlvii suggests that they contained the germs of subsequent, more credible ideas. i mportantly, the 'cult of the picturesque' and, to an even greater extent, the th century romantic movement (notably writers such as wordsworth, coleridge, sir walter scott, keats, shelley and the brownings, and painters such as turner and constable) had a seminal influence on attitudes to landscape and shaped the thinking of the early conservation movement. the preoccupation with landscape as scenery and a somewhat escapist emphasis on aesthetics, picturesque views and a romantic construction of nature, were pre-eminent in influencing legislation. moves to preserve the british countryside were born in the victorian era and, according to bunce, reflected the tripartite interest of: the protection of nature; enjoyment of fresh air, open space and scenery; and preservation of national heritage. the nature movement spawned numerous local botanical societies and field clubs by the s and a number of national bodies, including what is now the royal society for the protection of birds. although somewhat separate from the protection of beauty, much of the early nature conservation movement was in fact motivated by the aesthetic and psychological benefits of nature. this movement was also linked to the growth of rambling as an activity and it is interesting to note that a group known as the sunday tramps reputedly included the historian g m trevelyan (whose influence is noted below) amongst its leaders. "natural beauty" first appeared as a formal phrase in the legislation in the act to establish the national trust for places of historic i nterest and natural beauty. the act refers to the trust's purposes as "the preservation for the benefit of the nation of lands and tenements (including buildings) of beauty or historic interest and as regards lands for the preservation … of their natural aspect features and animal and plant life". i t thus appears to connect natural beauty with wildlife as well as with natural aspect and features, but no further definition of the term was provided. the trust was born out of the victorian heritage movement, which was particularly linked to the romantic movement and especially to the anti-industrial philosophies of william morris and john ruskin. for example, morris wrote eloquently of the beauty to be found in nature and, according to angus taylor xlviii, believed that "human well-being cannot be divorced from the well-being of the natural environment" and "everything made by man's hands has a form which must be either beautiful or ugly; beautiful if it is in accord with nature, and helps her, ugly if it is discordant with nature and thwarts her". his writings give a clear view of beauty in nature as the antithesis of urbanisation and industrialisation. ruskin was similarly condemnatory of industrialisation, and expressed nostalgia for the harmonious peasant culture of earlier times. these two leading thinkers had a significant influence on their contemporaries, robert hunter and octavia hill, who in initiated the idea of a trust to preserve important land and property, eventually to become the national trust. octavia hill was indeed a pupil and devoted follower of ruskin and, with her sister, established the kyrle society to promote 'beauty'. she wrote an essay entitled 'natural beauty as a national asset' arguing that access to beauty was an essential of life, like food, clothing, or shelter xlix . as the conservation movement established itself, and growing numbers of people were able to gain access to the countryside, rural nostalgia continued during the edwardian period and in the inter-war years. during this period, the first planning legislation emerged, whilst the need for protection of rural landscapes became a pressing issue. four leading advocates sought the appreciation and protection of rural landscapes – vaughan cornish, g. m. trevelyan, clough williams-ellis and patrick abercrombie – and all were linked, notably through the emergence of what would eventually become the campaign to protect rural england and its equivalents in wales and scotland. further, they played important roles in shaping the agenda for countryside preservation and national parks up to and after the second world war. they were involved in giving evidence to or sitting on the various official committees established and it seems clear that their views were influential: the legislative roots of "natural beauty" must, to a considerable degree, reflect their ideas and beliefs. vaughan cornish (i - ) was a geographer who in attended an address by sir francis young husband, the explorer, who made a plea for geographers to turn their attention to serious consideration of the beauty of natural scenery. thus inspired, he wrote a string of books and papers and campaigned for the preservation of fine landscape, often reflecting his own experiences - his book “beauties of scenery" l, for example, is a personal reflection about the nature of natural beauty in the british i sles. g. m. trevelyan ( - ) can perhaps be most closely linked with the use of the phrase natural beauty in the period leading up to its inclusion in legislation, and his seminal paper li remarked on the relationship between the increasingly conscious appreciation of natural beauty and its dwindling supply. he saw the natural beauty of the countryside as the inspirer and nourisher of science, religion, poetry and art, and urged its preservation in sufficient quantity to satisfy the thirst of the town dweller’s soul. the architect clough williams-ellis ( - ) was a leading figure in campaigns against the encroachment of development into the countryside, famously describing the tentacles of urban sprawl in 'england and the octopus'lii . he also brought together concerns about the effects of developments on other parts of britain in his editing of "britain and the beast". patrick abercrombie ( - ) was an early town and country planner who, amongst other things, solicited support for the creation of a broad coalition to advance the cause of the countryside, which led to the creation of the council for the protection of rural england (cpre), of which abercrombie was the first honorary secretary, followed two years later by the establishment of the council for the protection of rural wales (cprw). i n his planning work in the s he introduced the "abercrombian landscape survey" method, marking a more professionally focused departure from the personal and romanticised views of other luminaries. the history of the national parks and access to the countryside act has been widely documentedliii. i n a national parks committee was established under the chairmanship of christopher addison, with terms of reference "to consider and report if it is desirable and feasible to establish one or more national parks in great britain with a view to the preservation of the natural characteristics including flora and fauna, and to the improvement of recreational facilities for the people". according to mair and delafonsliv the committee held meetings and heard evidence from groups of witnesses as well as receiving written representations – interestingly, the national trust, abercrombie and vaughan cornish were among the contributors. the committee’s report in recommended various measures for preserving the countryside and specifically reflected the wording of vaughan cornish in places. i t favoured a system of national reserves and nature sanctuaries, in order, among other things, "to safeguard areas of exceptional natural interest against disorderly development and speculation" and "to improve the means of access for pedestrians to areas of natural beauty". there are perhaps hints in these phrases of the later emergence of "outstanding natural beauty" in the legislation. no action was taken in response to the addison report, but as a result of their lobbying of the committee, cpre and cprw together set up a 'standing committee on national parks' of which abercrombie was a member and which also included, among others, the national trust. trevelyan had been actively promoting the cause of the trust, for example in a paper entitled "must england's beauty perish" produced in . i n he turned his hand to national parks and, in the foreword to the standing committee's pamphlet 'the case for national parks in great britain'lv , he wrote of "regions where young and old can enjoy the sight of unspoiled nature … without vision the people perish and without sight of the beauty of nature the spiritual power of the british people will be atrophied". the report of the scott committee on "land utilisation in rural areas", , included an observation that the establishment of national parks was long overdue. the report reflected on the countryside’s close relationship with agriculture, observing that: "the landscape of england and wales is a striking example of the interdependence between the satisfaction of man's material wants and the creation of beauty. .. i ts present appearance is not by any means entirely the work of nature …the land of britain should be both useful and beautiful and that the two aims are in no sense incompatible… it must be farmed if it is to retain these features which give it distinctive charm and character." the dower report, published in , was another vital step towards the legislation for national parks. john dower, related by marriage to the trevelyan family, had been an advocate for national parks throughout the s and acted as drafting secretary for the 'standing committee on national parks’ paper on the case for national parks. the scott report emerged soon after he started this work and dower was then asked to broaden his work to complete a much longer report on national parks by november . i n his final report dower defined the meaning of a national park for britain as: "an extensive area of beautiful and relatively wild country in which, for the nation's benefit and by appropriate national decision and action, (i) the characteristic landscape beauty is strictly preserved " . dower's phrase 'characteristic landscape beauty' betrays the influence of the lobbying over the years by people like trevelyan (beauty) and cornish and abercrombie (landscape character). shortly afterwards, the hobhouse committee was appointed as part of the efforts directed towards post-war reconstruction. many of its members had been on the standing committee, including clough williams-ellis. the committee proposed national parks as well as a larger group of 'second order' conservation areas of high-value landscapes and habitats (subsequently ‘areas of outstanding natural beauty’), whose designation as " areas of high landscape quality, scientific interest and recreational value" was seen as an essential corollary to the national park proposals. when the act received royal assent in , section ( ) set out the purposes of national parks as including "the preservation of the natural beauty of an area", which section ( ) qualified by stating the "references in this act to the preservation of the natural beauty of an area shall be construed as including references to the preservation of the characteristic natural features, flora and fauna thereof". this was amended in to 'its flora, fauna and geological and physiographical features' and in addition the word 'preservation' was replaced by 'conservation'. over the years section ( ) has been interpreted as a partial definition of the meaning of "natural beauty”, in the sense that it makes clear that "natural beauty" includes these considerations, but is not restricted to them. section ( ) related to the designation criteria for national parks, similarly referring to ‘natural beauty’ – however, as noted later, it is unclear whether s ( ) can be construed as relating to designation criteria, or only to planning and management purposes. there is little evidence to indicate how the final phrasing of the national parks and access to the countryside act came into being. cherrylvi describes how a secretary to the ministry of town and country planning in wrote an internal note about the then minister's predilection for a national commission to be established with responsibility for "areas of natural beauty" . by the time that the act received royal assent in december "natural beauty" had become the preferred phrase to express these ideas. several other phrases had been used to convey the idea of important landscapes, for example, features of particular landscape importance or landscape value and rural areas of remarkable landscape beauty (abercrombie) landscape character and landscape pattern (scott) characteristic landscape beauty (dower), high landscape quality (hobhouse) and high scenic value (minister of town and country planning). despite this "natural beauty" prevailed, for reasons which are not apparently disclosed anywhere, yet which can be taken as a shorthand for all these other concepts. i t also of course had resonance with the existing national trust legislation, which may have influenced those drafting the legislation. "natural beauty" has continued to be the accepted official phrase to encapsulate ideas about the value and importance of landscape, and is now found in legislation that amends or adds to the national parks and access to the countryside act, notably the countryside act and the environment act , as well as in the agriculture act and the accompanying ec regulation relating to environmentally sensitive areas, the wildlife and countryside act and the countryside and rights of way act . despite its widespread use in legislation it has never been formally defined even though many over the years have found it a clumsy and unhelpful phrase. whilst the early legislators presumably felt its meaning to be self-evident, in practice it contains many latent tensions, not least that of deciding the point at which a landscape, however attractive, ceases to be ‘natural’ by virtue of the intensity of human settlement and land use. the next section considers how the term has been elaborated and contested as it has been applied in different contexts. the concept evolves: policies, practices and public inquiries the original ten national parks in england and wales were formally designated between and and the first tranche of aonbs were confirmed for designation by . the first official review of the national parks, the sandford review, which took place in lviii lvii had little to say about the definition or interpretation of "natural beauty" but did establish the primacy of the "natural beauty" purpose. four years later the countryside commission appointed kenneth himsworth to undertake its first review of aonbs. his report, published in lix , similarly addressed the balance between the different purposes of designation and noted that the act provided "no guidance as to the calibration of 'outstandingness' in the quality of natural beauty" nor did it comment on the interpretation of natural beauty itself. himsworth did, however, note that "aonbs come in all shapes and sizes….. there is no single character". i n a signal departure from the vagueness of terminology surrounding criteria for selection and definition of national parks and aonbs, the countryside commission in appointed consultants to carry out a study of the kent downs aonblx which considered, inter alia, the meaning by outstanding natural beauty and the requisite qualities to make a landscape outstanding. i n addressing these issues it emphasised ‘characteristic’ features, such as the abundance and integration of the distinctive elements, richness and unity, important influences of variable factors such as season and weather, the sweeping and rounded form of the land, and the human scale of the landscape. i n addition the study makes particular reference to links between contemporary perceptions of the landscape and the paintings of samuel palmer who is closely associated with the kent downs landscape, particularly the area of the darent valley. this approach to extensive description of the character and special qualities of landscape, including detailed reference to how they have been recognised in the work of artists and writers, came to the fore in the s, perhaps as a reaction against the emphasis on quantitative approaches during the s. i n the new approach found clear expression in a report on the new forest landscape which set out the value of the area from a landscape perspective, to balance the longstanding emphasis on its national and international significance for wildlife and nature conservationlxi . i t notes how, even years earlier, evidence to the house of commons select committee had made reference to the beauty and varied character of the new forest and its great national value - "an object of value as great as exists in any work of art, although the new forest is one of nature". a further influence was the production of guidance for the national park authorities on the implementation of section of the wildlife and countryside (amendment) act which amended section of the wildlife and countryside act . these sections required the national park authorities to produce a map of particular types of land (mountain, moor and heath in , with woodland, down, cliff and foreshore added in ) "whose natural beauty it is, in the opinion of the authority, particularly important to conserve". the accompanying guidancelxii considered a number of different aspects of the meaning of "natural beauty” relating these to "pleasure to the senses", and noting that ‘natural’ did not preclude human agency: "it is not inconsistent with the concept of natural beauty to include such landscape elements as designed parklands, archaeological features, fields bounded by walls and even buildings where they are intrinsic elements in the wider landscape." while accepting the primary importance of visual qualities, the guidelines also recognised that people react to landscape through sounds, smells, taste and touch. thus, "natural beauty" arose from a combination of a series of complex and varied factors including physiography (e.g. geology, ecological habitats), associations (historical and cultural), aesthetics (visual and other senses), status relative to other areas (degree of rarity or typicality), feelings evoked in the observer, and public accessibility. this inclusive definition is significant because it reflects an explicit statement about what the commission saw as being valuable in terms of “natural beauty” within a public statutory document. a second review of national parks, under the chairmanship of professor ron edwards, reported in lxiii that the purposes set out in the original legislation for national parks were in need of revision. they reasoned that "the national parks embrace much more than the conservation of fine scenery; wildlife, archaeological features, the man made heritage and other cultural qualities are also essential elements of their special quality". as a result they recommended that the first purpose of national parks, of "preserving and enhancing the natural beauty of the areas" should be re-defined as "to protect, maintain and enhance the scenic beauty, natural systems and landforms, and the wildlife and cultural heritage of the area". this might imply a desire both to update and to clarify the meaning of "natural beauty" by indicating the full breadth of meaning that it encompassed in modern usage in the s. i t is interesting to note that the panel proposed this detailed change to the first purpose but did not at the same time suggest any change to the qualifying section ( ). the recommendations of the panel were partly reflected in the changes to national park purposes set out in the environment act ( ) where the first purpose is re-stated as "conserving and enhancing the natural beauty, wildlife and cultural heritage of the areas…". i nstead of replacing "natural beauty" with a broader phrase the act retained "natural beauty" in the national park purposes, but added the duty of conservation and enhancement of wildlife and cultural heritage. there was no change to section ( ) defining the criteria for designation. "natural beauty" therefore remained undefined, but still qualified by section ( ) indicating that in references in the act to the preservation, or the conservation of the "natural beauty" of an area "natural beauty” includes, but is not confined to, flora and fauna and geological and physiographical features. at this time the former department of the environment also published a circular lxiv which defined national parks as "areas of exceptional natural beauty (containing) important wildlife species and habitats…but the parks are also living and working landscapes and over the centuries their natural beauty has been moulded by the influence of human activity. their character is reflected in local traditions which have influenced farming and other land management practices. i t is also reflected in the local building material and vernacular style, monuments and landscapes, often of archaeological or historical significance, and in the words, customs, crafts and art which mark the individual characteristics of each park". arguably, this could be taken as confirmation of a broader view of the meaning of "natural beauty" in that the comments about wildlife, the influence of human activity, management practices and historical aspects can be read as qualifications of the first statements about "exceptional natural beauty". i t is clear that there has been a gradual clarification of what "natural beauty" means when applied to valued or designated landscapes. ‘landscape’ and ‘character’ are starting to be recognised as closely related but nonetheless different terms, and there is a growing acknowledgement of the difficulty of applying universal rules of aesthetic appeal in a meaningful way. character is emerging clearly as the basis for describing the special qualities of individual landscapes and beauty is being interpreted as an expression of landscape quality, related to particular characteristics of different areas, and of the values that are attached to different landscapes, aided by a historical perspective of the ways that artists and writers have responded to them over the years. these emerging conceptions were vigorously tested in the first legal examination which touched on the meaning of "natural beauty", namely, the public i nquiry into the designation of the north pennines aonb in england. i n his opening address to the inquiry, the countryside commission's qc argued that from a legal standpoint 'beauty' must be "construed subject to section ( )". this section amplified natural beauty by reference to flora, fauna, geological and physiographic features, and thus it was argued that "such features, if worthy of preservation (which may be because of their scientific interest rather than aesthetic quality) are to be treated as included within the concept of beauty". the qc was clear that the list of ‘features’ is not intended to limit the definition of natural beauty to these aspects but rather to extend the meaning - that is to ensure inclusion of things which might otherwise have been excluded. since neither the i nspector nor the minister disagreed with his interpretation, it must be presumed to have a degree of official sanction: " 'natural' in the context means therefore no more than 'not artificial'. sometimes man has laboured to create beauty [ through works] of 'artistic' or 'architectural' beauty. the phrase 'natural' beauty is merely used in contrast to such examples. i t does not exclude beauty in which man has had a hand, or which arises as a by-product of or survives man's activities; only beauty which is the deliberate creation of man. the effects of s ( ) adds to it, not only natural features worthy of conservation even if not beautiful but also artificial creations out of growing things such for example as a landscaped park. thus it is not inconsistent with the concept of natural beauty to include fields bounded by man-made walls, although the use of local material may be essential if that is not to disturb the natural beauty. no more is it inconsistent to view settlements and villages, of such quality at least as not to disturb the beauty of the area, as part of its natural beauty. the key evidence dealing with the policy framework for aonb designation and interpretation of their purposes and the criteria for designation was provided by the countryside commission’s director lxv , who observed: "though the statute speaks of 'outstanding natural beauty', in practice this means outstanding landscape quality. this is because there are few, if any, areas of england and wales, which are entirely natural..." this evidence is amplified by reference to the factors that countryside commission staff considered when judging "natural beauty" or landscape quality, namely, relative relief, landscape shape, natural quality (or wildness), semi-natural vegetation, dramatic contrasts, remoteness, unspoiled quality, continuity and extent, harmony of the works of man and nature, and vernacular architecture. i n his report following the i nquirylxvi the i nspector wrote "in considering the 'central issue', the assessor and i agree with the commission that natural beauty is in practice best interpreted in the context of a proposed aonb as landscape quality" and in his findings of fact he noted that "the quality of the landscape of the area is both natural and man-made". this provides the first clear evidence of landscape quality being used in practice in place of natural beauty, albeit there is no attempt to clarify what landscape itself means, nor indeed quality. the secretary of state in his decision letter accepted the i nspector's conclusions and recommendations and expressed the view that "assessment of landscape quality necessarily involves a subjective assessment and that within the consensus of informed opinion allied with the trained eye, and commonsense, the matter is one of aesthetic taste". this has been an important statement in subsequent considerations of "natural beauty". the findings of this public inquiry resonated strongly with emerging interpretations of landscape as an environmental system which can be described in terms of its character and mapped as a geographical unit. i n particular, it gave considerable impetus to the need for statutory organisations to be more explicit in their identification and treatment of special landscapes. thus, having rejected statistical approaches to landscape classification and evaluation, the countryside commission facilitated the development of more qualitative methodslxvii, which began to consolidate the view that the analysis, description and classification of landscape character had to be considered separately from the steps of evaluation or other forms of judgement. these views were reflected in the commission’s work to prepare its own internal guidance for staff on approaches to landscape assessment, later published for a wider audience lxviii, and subsequently elaborated into the method of landscape c haracter assessment. i n further recognition of the need to be much more explicit about what "natural beauty" means in practice, the countryside commission set about commissioning and publishing landscape assessments of all the proposed and designated aonbs. these assessments were designed to provide a statement about why each of the areas was considered important in terms of its landscape character and quality. emerging wisdom was confirmed in the first of these publications, whose preface concluded that, whilst the determination of natural beauty should primarily reflect visual quality, geology, topography, flora and fauna, historical and cultural aspects were also relevant. the study proceeds to address this question through a process of "informed opinion, the trained eye, and common sense" as recommended by the countryside commission's landscape assessment guidance, which in turn reflected the conclusion of the north pennines inquiry. i n , work commenced to designate two new national parks in england, the new forest and the south downs. both proposals were subject to public i nquiries, in anticipation of which the former countryside agency produced a series of papers between and reviewing the application of the criteria for national park designationlxix . landscape character assessment and guidance on its application played an important part in both inquiries. the i nspector at the new forest inquiry was assisted by a specialist landscape assessor who advised on the issues relating to the "natural beauty" criterion. the assessor reviewed the legislation, the “natural beauty” criterion and the way the countryside agency had applied it in relation to the new forest and the definition of its boundarylxx . a key consideration in defining the boundary for this area was the use of a broad definition of “natural beauty” which included “flora, fauna, geological and physiographic features, and elements arising from human influences on the landscape, including archaeological, historical, cultural, architectural and vernacular features". i nterpretation of the "natural beauty" criterion was in this case heavily based upon a landscape character assessment conducted in which identified and mapped landscape types which possessed a common identity recognisable as the new forest landscapelxxi . the landscape assessor supported the view that the primary consideration of natural beauty was the presence of outstanding landscape quality reflected through the presence of intact and distinctive new forest landscape character, with an absence of atypical or incongruous features. she stated: "all the landscapes of england are heavily influenced by human activity. bearing that in mind, natural beauty as defined in section ( ) of the act cannot imply pristine or completely natural landscapes or there would be no land in england that could meet the natural beauty criterion. the terms of the act must therefore require a high degree of 'relative naturalness' accepting that the cultural influences on the landscape should be taken into account…" lxxii the main issue of contention was the degree to which weight should be attached to factors such as history, cultural associations, considerations relating to use of the land for common grazing, archaeology and nature conservation interests, even where these were unrelated to landscape beauty. the assessor felt that the weight to be attached to such matters needed to be carefully considered if they were not to be given undue attention in reaching judgements on natural beauty. this raised the difficult legal question of whether the qualifying statement about the definition of natural beauty in section ( ) relates only to the statutory purposes of designation set out in section ( ) or also to the designation criteria in section ( ) where "natural beauty" is unqualified. following confirmation of the new forest national park boundary in march , meyrick estate management limited and others appealed to the high court against the inclusion of hinton park within the area. the high court judge, mr justice sullivan, found in favour of the claimants. there were several grounds for the claim, but among them the claimants argued that the defendant (the secretary of state) had erred in the law: "i n not applying the statutory test in paragraph (a) of subsection ( ) "natural beauty", but the extended definition applicable under section ( ) only to the management of national parks under subsection ( ) once they had been designated under subsection ( )." the landscape consultant for the claimants commented that: “the countryside agency's revised approach to boundary making is to include areas of historical value. this is misguided as marginal areas are inappropriately included based on a flawed understanding of natural beauty". this argument was strongly contested at the inquiry by the countryside agency who argued that: "guidance and precedent clearly indicate that historical, cultural, architectural and vernacular features form part of natural beauty. … that is why landscape, ecological, historical and cultural considerations i.e. commoning, were each considered in turn in section and of the 'new forest national park boundary study"… all of these factors (i.e. landscape; ecological; historical and cultural) were assessed as part of the 'natural beauty' criterion…" i n weighing up the balance of arguments, the judge did not accept the agency’s case relating to the application and meaning of section ( ), suggesting that the extended meaning of “natural beauty” is related to possible conflicts which may arise from the different purposes of designation such as those between recreation pressure and the protection of rare flora. the judge criticised the conclusions of both the landscape assessor and the i nspector, concluding that "in some contexts 'natural' might simply mean rural, as opposed to urban, but 'natural beauty' has to be understood in the context of section which is concerned with the designation of ‘extensive tracts of country ’ which have the particular quality of natural beauty (whereas) ‘well maintained’ historic parkland providing the setting for a grade i listed building, and 'well ordered' dairy fields of dairy farms would seem to be the antithesis of naturalness. i n such landscapes man has very obviously and deliberately tamed nature". the judge considered that "the assessor and the i nspector's approach effectively discarded the requirement for a high degree of relative naturalness and substituted a test of 'visual attractiveness' or 'landscape quality' “. i n moving towards his conclusion the judge noted that the issue of proper application of section ( ) was "not the determining issue". i nstead he turned to the fact that the agency was contending that a broader range of factors, including, for example historical and cultural factors, could be taken into consideration in deciding whether the "natural beauty" criterion was met. he concluded that: "while such factors were relevant (as the assessor said) to an understanding of how a particular tract of countryside had evolved to its present state, they were not relevant when it came to deciding whether it possessed the necessary quality of natural beauty so as to justify designation as a national park". this ruling therefore took a narrow view of "natural beauty", bringing into question much of the subsequent evolution of its interpretation in policy and precedent. the department for environment, food and rural affairs (defra), representing the interests of the agencies involved in the original case, contested the high court ruling but in the court of appeal upheld the decision, although its reasons related to whether opportunities for open air recreation existed and it was of little help in reaching a firm view of the correct legal interpretation of natural beauty. i n making the original decision in the meyrick case the high court suggestedlxxiii that legislation was needed to clarify the meaning and use of natural beauty in designating landscapes for protection, noting that: “views as to which tracts of countryside have the quality of "natural beauty" may (or may not) have changed over the last years, but the "natural beauty" criterion in subsection ( )(a) of the act has not been changed to embrace wider considerations such as "cultural heritage". i f the "natural beauty" criterion in subsection ( )(a) is to be changed to reflect st century approaches to countryside and leisure planning then the change must be effected by parliament, and not by administrative action on the part of the agency in adopting a wider range of factors for the purposes of designation.” concerned at the implications of the high court ruling for the ongoing i nquiry into the proposed south downs national park, the relevant authorities had to a degree anticipated this conclusion. taking advantage of the imminent introduction of the natural environment and rural communities act , a new clause was added very late in the proceedings, with the intention to pre-empt any further debates about the meaning of natural beauty. this new clause provided that, when considering natural beauty, an area’s wildlife and cultural heritage may be taken into account (section ( a)(a)); such an area may include land which consists of or includes land used for agriculture or woodlands, or used as a park, or an area whose flora, fauna or physiographical features are partly the product of human intervention in the landscape (section ). it remains to be seen whether this is a sufficient basis for modern landscape protection, planning and management, such as that required under the european landscape convention. stakeholder view s on “natural beauty” i t is clear that the interpretation of the term “natural beauty” is not as self-evident as its originators presumed. i ndeed, it is openly contested, bringing into question whether it should be more explicitly defined or perhaps replaced altogether with an alternative expression. this question was explored with a group of stakeholders, in the form of a written consultation and a workshop. both groups received a summary of the researchers’ review and a draft re-definition, of “natural beauty”. a number of individual expressions and convergent themes were suggested by respondents and attendees during these exercises (table ). a recurrent theme was the intangibility of natural beauty and hence the need to ensure that it reflected non-quantifiable and emotional qualities, which often could not be precisely defined or specified. not being a purely objective quality possessed by the land, it was seen to relate to the capacity of land and water to evince emotional responses. i t was seen as a fluid concept, as cultural evolution leads to changes in what is recognised as being beautiful. i t is also a multi-sensory quality – not purely visual – and thus properties such as tranquillity and sense of freedom contribute to the human response. i t could also have a ‘spiritual’ quality, given the historical association between ‘re-creation’ and inspiring places. some respondents were concerned that too formulaic a definition might trivialise some of these profound qualities. respondents felt that natural beauty did not need to be restricted to areas which were either extensive or wholly free from industrialisation. on the one hand, society is increasingly prepared to recognise the beauty associated with urbanisation and industry, even where the landscape scars have only recently started to heal. on the other, ‘unspoilt’ natural beauty was often to be found in quite small areas, whereas legislation and past practice tended to equate it with the grand scale. these smaller enclaves were often close to large settlements and thus valued by many people and so it was important to have a definition which allowed acknowledgement of natural beauty wherever it occurred. whilst respondents tended to describe natural beauty in ‘universal’ terms rather than place- specific ones, there were some allusions to particular associations with the welsh language and culture. for example it was noted that the difference in language is closely related to the understanding of place. the welsh language includes helpful terms such as tirlun for the ‘visual’ qualities of landscape and tirwedd for a richer view reflecting wider associations, whilst the notion of hiraeth reflects people’s yearning for places they cherish. further, the time-depth of landscape was considered to a very important contributor to what is perceived as beautiful, and in wales this has been reflected in a register of historic landscapeslxxiv. the continued usefulness of natural beauty as a concept caused some division of opinion. a significant minority suggested that the term was outmoded and needed to be replaced: first, it was felt that human use had shaped the environment for so long that the notion of ‘natural’ was misleading; and second, beauty is a category of the aesthetic, and thus some people saw it as an inappropriate subject for legislation. the terms natural and beauty were felt to be unclear and disingenuous, both individually and in combination, and could usefully be replaced by a new term. most respondents, however, were in favour of retaining the concept, mainly for pragmatic reasons, albeit with a deeper support for the term’s intrinsic meaning. both the supporters and opponents of the term were keen to pursue the use of new terms, either as supplements to or replacements of natural beauty – these included fine scenery, high quality rural landscape, special landscape, natural and cultural heritage (qua scottish national parks), and relative naturalness (in a small and crowded country with strong anthropogenic influence). some were particularly keen to see harmonisation with international terminology, particularly with i ucn category v protected landscapes, the world heritage convention and the european landscape convention. there was a feeling that most people understood ‘natural’ as being where human control is ‘relaxed’, making it easier to see that landscapes are still shaped by elemental forces of nature such as weather, tides, seasons, gravity, soils, geology and water. a common view was that natural beauty remained a useful concept provided it was elaborated through criteria based on positive contributors and negative detractors. some respondents sought criteria that were primarily visual, reflecting the essential aesthetic and perceptual qualities of beauty; authenticity was similarly mentioned. this view was closely related to emergent properties such as tranquillity, relative lack of pollution, wildness, relative naturalness, integrity and associations. others sought scientific criteria, reflecting legal references to flora, fauna, geology and physiography. one interesting and strongly made viewpoint was that accessibility was a key criterion. given that beauty has to be seen to be appreciated, then it is axiomatic that people should be able to view it at first hand. however, some respondents were keen not to introduce criteria, feeling that this would detract from the transcendental and indefinable qualities that were most precious. further, society is constantly redefining its attitudes about things that it deems to be beautiful, and thus quantifying and specifying such a fluid notion could prove a contradiction in terms. one strongly expressed viewpoint by a number of respondents was that natural beauty is a ‘democratic’ concept and possesses an aesthetic which relies on the observer’s response – thus, it was important to ask the public what it considered to be beautiful. clearer definition of the term was felt to be important for a number of reasons: the need for a legally robust definition, especially in the post-meyrick context; generating an improved understanding of the role of national parks; providing a clear thread between the european landscape convention and domestic practice; interpreting s legislation in a modern way that reflected evolution of thinking about landscape; and ensuring that the term was not ‘overloaded’ by expecting it to apply to all manner of situations inside and outside national parks. a common view was that a definition of natural beauty should strike a balance between having a popular currency and yet also being fit for legal purpose. subsequent reflection and discussion emphasised the importance of defining ‘natural beauty’ rather than ‘outstanding natural beauty’. many parts of the country may thus be considered to possess a degree of natural beauty – however, some places could display this quality to an outstanding degree, and so may be worthy of special designation. criteria that workshop members thought might be taken into account in defining natural beauty are summarised in table . conclusion the foregoing account has analysed the continuing relevance of natural beauty as a legal term underlying the safeguard of protected landscapes in the uk, particularly england and wales. during the th and th centuries, there is evidence of a progressive consensus that ‘nature’ – rather than being associated with hazard and privation – could be treated as a category of the aesthetic alongside human form and artefacts. for various reasons, this view became enshrined in a particular bureaucratic and legislative movement. even though it is clear that successive guidance and professional judgement has drawn upon an increasingly sophisticated view of ‘landscape’, and despite the apparent vulnerability of the term to legal challenge, natural beauty is still widely considered to be ‘fit for purpose’ as a basis for designating and managing protected areas. however, it is a somewhat archaic term which clearly needs qualification and clarification. taking account of the various sources of evidence and opinions, we suggest that the following attributes relate to a modern understanding of natural beauty:  natural beauty relates, first and foremost, to unspoilt rural areas free from large-scale settlements or industry;  natural beauty does not apply only to landscape where nature may appear to dominate, but includes rural landscapes which have been shaped by human activities, including, for example farmland, fields and field boundaries designed parkland, small settlements, larger villages and small towns, provided that they are integral to and in keeping with, the character of the landscape. traces of industrialisation may not always be incompatible with, and may sometimes be complementary to, beauty;  natural beauty is a broad concept that is concerned with ‘landscape’, which is now itself inclusively defined as: the interaction between the physical (geology, landform, air and climate), natural (soils, flora and fauna), and cultural/ social (land use, enclosure, settlement) components of our environment; and the way this is perceived by people visually, in terms of aesthetic aspects like colour, form, texture and pattern, and through other senses, and also through perceptions and preferences, which are affected by people’s cultural backgrounds and interests;  natural beauty is related to landscape character, in that it will find expression in areas of landscape which have a degree of unity and distinctiveness in character and a strong sense of place. landscape character is, however, found everywhere whereas natural beauty is found in valued landscapes;  in the th and the first half of the th centuries, when landscape was still viewed largely as a static scene or picture, natural beauty was used mainly to reflect the value attached to the aesthetic and scenic aspects of landscape. the aesthetic values attached to landscape, though still important, are only one of the reasons why landscape is now valued;  natural beauty is about landscape value and thus draws upon the different reasons why society may attach value to particular areas. these are increasingly established through recurrently used criteria (table ). not all of these criteria need be met for an area to possess natural beauty; however, where many of them coincide spatially, that area may be considered to possess ‘outstanding’ natural beauty. i n the context of ‘protected landscapes/ seascapes’, we conclude that natural beauty relates, first and foremost, to unspoiled rural areas, relatively free from the effects of urbanisation and industrialisation. i t does not apply only to landscape where nature may appear to dominate but includes rural landscapes which have been shaped by human activities, including, for example farmland, fields and field boundaries, designed parkland, small settlements, larger villages and small towns, provided that they are integral to, and in keeping with, the character of the ‘landscape’. overall, therefore, it appears that the concept of natural beauty retains a contemporary meaning distinct from the evolving 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( ) nature in trust: the history of nature conservation in britain. blackie and son. glasgow and london. sheail, j. ( ) nature conservation in britain: the formative years. the stationery office.london. macewen, m. and a. ( ) national parks: conservation or cosmetics? george allen and unwin. london. bishop, k., nicholls, c., ormerod, s., phillips, a., and warren, l. ( ) protected areas in the welsh countryside. volume – protected areas – past, present and future. research report to the countryside council for wales. environmental and countryside planning unit. university of wales college of cardiff. liv mair, j. and delafons, j. ( ) the policy origins of britain’s national parks: the addison committee - . planning perspectives. vol. . pp - . lv according to cherry, g.e. ( ) environmental planning – . volume ii. national parks and recreation in the countryside. hmso. london. lvi ibid lvii sandford, lord (chairman) ( ) report of the national park policy review committee. london. hmso. lviii the national parks commission, set up in was replaced by the countryside commission in , itself being merged into a new countryside agency in , which in turn was incorporated into natural england in lix himsworth, k. m. ( ) a review of areas of outstanding natural beauty. report for the countryside commission, ccp , cheltenham. lx land use consultants ( ) the kent downs area of outstanding natural beauty. report to the countryside commission. lxi land use consultants ( ) the new forest landscape. ccp . countryside commission. cheltenham. lxii countryside commission ( ) wildlife and countryside acts and : section conservation maps of national parks - guidelines. ccd . countryside commission. cheltenham. lxiii edwards, r (chair) ( ) fit for the future: report of the national parks review panel. countryside commission. cheltenham. lxiv department of the environment ( ) circular / . hmso. london. lxv phillips, a. ( ) north pennines aonb public inquiry: statement by the director of the countryside commission. unpublished statement of evidence. lxvi berthon, sir stephen ( ) north pennines aonb (designation) order : report of public local inquiry (reference: dra /cw/ ) lxvii land use consultants ( ) mid wales uplands: landscape assessment. unpublished report to the countryside commission. cheltenham. cobham resource consultants ( ) landscape assessment of rivers. unpublished report to the countryside commission. cheltenham. lxviii countryside commission ( ) landscape assessment - the countryside commission approach. ccd . countryside commission. cheltenham. lxix the relevant documents are: board paper ap / : national park designation a review of how the criteria are applied and an updated and amended version of this in board paper series / board paper ap / designation of a national park in the south downs board paper / definition of national park boundaries paper on 'the statutory national park criteria, their interpretation and application' lxx hughes, r. ( ) landscape assessor's report on issues relating to the natural beauty criterion. defra. london. lxxi land use consultants ( ) proposed new forest heritage area boundary. new forest committee. lyndhurst. lxxii hughes, r. ( ) op cit. lxxiii high court judgment in meyrick estate management & others v secretary of state for environment, food and rural affairs [ ] ewhc (admin), paragraph . lxxiv countryside council for wales (ccw)/ cadw ( ) register of landscapes of special historic interest in wales. cardiff: cadw. selman, p h and swanwick, c a ( ) on the meaning of natural beauty in landscape legislation. landscape research, vol. , no. , – . doi: . / on the meaning of natural beauty in landscape legislation paul selman and carys swanwick department of landscape, university of sheffield introduction reviews rightly understood and appreciated in consciousness, it has value in pro- moting psychological harmony. a good example of the function of the unconscious which consists in presentation of the psychological situation is the dream of the neurotic lady who identified herself with her suffering mother. the free associations of the dreamer are tabulated. the piecing together of these associations is shown to give an accurate representation of the patient's psychological situation in the early stages of analysis. this is an admirable piece of technique, on which dr. long is to be congratulated. the keynote of the book is to be found at the beginning in the quotation from jung's psychological types (not yet published). an extract may be given: " it was, and always is, phantasy which builds the bridge between the irreconcilable claims of the object and of the subject, of extroversion and introversion." dr. long shows how regressive phantasy is always the agent which prevents the patient from taking up the normal burden of life. on the other hand, she vindicates the truth of the above statement by examples of phantasy which, constructively handled, indicate the way out from tlhe neurotic impasse. technical terms are used sparingly throughout. it is therefore.a book eminently suitable for the general reader, and it is to be hoped that it may stem the present tide of misrepresentation and exploitation, a danger which is peculiarly liable to beset any new form of science. james young. personal beauty and racial betterment. by knight dunlap, pro- fessor of experimental psychology in the johns hopkins university. cr. vo. pp. . . london: henry kimpton. s. in this eugenic tract the author lays down the principles of beauty in the human person. he asserts that certain characteristics, negative and positive, must be fulfilled in order that a person may be regarded as beautiful, that is 'fitted for parenthood', and in the first part of the book these are defined. in the second part he gives his views as to how beauty is to be con- served and propagated. he points out the harm done by prostitution in spreading venereal disease, but at the same time remarks that it does something to prevent the propagation of the feebleminded in view of the low conception-rate amongst prostitutes and the large proportion of feebleminded in their ranks. he shows good sense in insisting that eugenics cannot be enforced by law, but only by education and publicity, and quotes the tabus against incest and inbreeding to show how easily the sexual impulses are controlled by convention. he considers that at present the world is over-populated, and that the only remedy is to spread the knowledge of how to prevent conception amongst the classes which are multiplying with undue rapidity. at - the same time he points out how the most beautiful women are at ' b y co p yrig h t. o n a p ril , b y g u e st. p ro te cte d h ttp ://jn n p .b m j.co m / j n e u ro l p sych o p a th o l: first p u b lish e d a s . /jn n p .s - . . o n m a y . d o w n lo a d e d fro m http://jnnp.bmj.com/ reviews -present lost to parenthood, either by making wealthy marriages, when the demand for luxury bars large families, or by being selected for the stage. he thinks that the war may have had some influence in reviving sextual selection.amongst women; that is to say, that they were more inclined to consider the physical attractions of the man than his wealth and position. he concluides by appealing to all concerned to see to it that laws, conventions, and economic conditions are shaped so as to conserve beauty instead of hindering its propagation. r. g. gordon. john wright' and sons ltd., bristol, printers and publishers. lo i b y co p yrig h t. o n a p ril , b y g u e st. p ro te cte d h ttp ://jn n p .b m j.co m / j n e u ro l p sych o p a th o l: first p u b lish e d a s . /jn n p .s - . . o n m a y . d o w n lo a d e d fro m http://jnnp.bmj.com/ please scroll down for article this article was downloaded by: [maloof, joan] on: june access details: access details: [subscription number ] publisher routledge informa ltd registered in england and wales registered number: registered office: mortimer house, - mortimer street, london w t jh, uk international journal of environmental studies publication details, including instructions for authors and subscription information: http://www.informaworld.com/smpp/title~content=t measuring the beauty of forests joan maloofa a salisbury university, biological sciences and environmental studies, salisbury, md, usa online publication date: june to cite this article maloof, joan( ) 'measuring the beauty of forests', international journal of environmental studies, : , — to link to this article: doi: . / url: http://dx.doi.org/ . / full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf this article may be used for research, teaching and private study purposes. any substantial or systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. the publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. the accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. the publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. http://www.informaworld.com/smpp/title~content=t http://dx.doi.org/ . / http://www.informaworld.com/terms-and-conditions-of-access.pdf international journal of environmental studies, vol. , no. , june , – international journal of environmental studies issn - print: issn - online © taylor & francis http://www.tandf.co.uk/journals doi: . / measuring the beauty of forests joan maloof* salisbury university, biological sciences and environmental studies, henson hall, camden ave., salisbury, md , usa taylor and francisgenv_a_ .sgm (received february ) . / international journal of environmental studies - (print)/ - (online)original article taylor & francis joanmaloofjemaloof@salisbury.edu aesthetic considerations are increasingly being taken into account when forest management decisions are made, but more quantitative studies testing assumptions are needed. this study tests the assump- tion that mature forests are perceived as being more beautiful than young forests; it also tests the philosophical concept of ‘serious beauty’, which hypothesises that the more knowledge one has about the ecological functioning of an environment, the more beautiful it will seem. all tests were done in situ. university students (n = ) rated the mature forest as more beautiful than the young forest. the young forest was rated as less than neutral in appearance, and the mature forest was rated as more beautiful than neutral. male students rated the forest as more beautiful than the females did. no significant difference was seen between the ratings from before or after an ecology presentation. thus we did not confirm the serious beauty hypothesis in this instance. keywords: environmental aesthetics; forest age; serious beauty; nature aesthetics; gender perception introduction the quality of ‘beauty’ is largely thought of as being based on subjective feelings that differ from person to person. but is beauty really judged differently by different individuals? is it merely ‘in the eye of the beholder’? although this is what many have been led to believe, when these questions are assessed quantitatively we find that the experience of beauty is more univer- sal than individual. the studies that have been done, mostly by psychologists or landscape architects, find that we have a common aesthetic sense, and that arguments against the objec- tivity of aesthetic judgments usually overstate the extent of disagreement [ , ]. for example, in studies where participants were asked to rate photographs of various scenes, a solid preference was shown for scenes of the natural world, and particularly for scenes including trees [ , ]. these preferences often lead to conflicts when the public objects to the cutting of trees – on both public and private lands. forest defenders frequently cite biodiversity and carbon sequestration as reasons for leaving the forest uncut, but just as frequently they note the beauty of the forest. the consensus seems to be that older forests are more beautiful than younger forests. studies done in the american southwest confirm that that number one predictor of scenic beauty, at both the stand and the site level, is the size of the trees: the larger the trees the higher the estimates of scenic beauty [ – ]. *email: jemaloof@salisbury.edu d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e j. maloof in recent decades, in part to avoid these conflicts, forest managers have been asked to take the aesthetic impacts of their logging plans into consideration; but methods of aesthetic assessment of forested landscapes have been spread out across disciplines as diverse as land- scape architecture, economics, philosophy, geography, and psychology; and no consensus has been reached on a common methodology [ , ]. frequently assessments are based on photographs, or the opinion of only a few persons [ – ]. the aesthetics of beauty have traditionally been the domain of philosophers, but recently a few leading philosophers of environmental aesthetics have suggested that ecologists trained in natural history are those best able to appreciate nature’s beauty [ , ]. these contempo- rary philosophers agree that beauty is more than just form; knowledge is involved in its interpretation, particularly knowledge of the natural sciences. the philosophers argue that because ecologists understand the workings of nature, the beauty that ecologists see in a forest is a more ‘serious’ beauty (in the terminology of the philosophers). this understanding leads to appreciation, appreciation leads to valuing the aesthetics, and valuing the aesthetics leads to an enhanced experience of beauty. the notion that people alter their preferences as a result of learning new information is also termed an ‘ecological aesthetic’ in contrast to an uninformed ‘scenic aesthetic’. ecologists, on the other hand, have largely shrugged off the responsibility for determining nature’s beauty. if pressed to explain our aesthetic sense, ecologists are more likely to cite responses developed through natural selection during human evolution than recently acquired knowledge [ ]. my research questions quantitatively measure perceptions of natural beauty. in this study i test whether an educational presentation on forest ecology immediately prior to experiencing the forest makes a difference in the rating of its beauty. (this is the ‘serious beauty’ hypothe- sis of the philosophers.) i also test whether a mature forest stand is perceived as being more beautiful than a younger forest stand. i test these questions within the forest, not by photographs. materials and methods university students of varying majors between the ages of and , and enrolled in an introductory biology class, were bussed in groups of – to an area where a young forest stand and a mature forest stand exist in close proximity (the nassawango field station, wicomico county, md, usa). the study was conducted during regularly scheduled labora- tory sessions, – october . as each class arrived students were divided randomly into two groups. one group was led directly to the forest where students were told only that they were participating in a research project investigating environmental aesthetics. no mention was made regarding the age of the forest stands. students entered either a young or mature forest on a m long path, where they completed the survey while standing, surrounded by the forest. the ‘young’ forest was a loblolly pine plantation, typical of the area. native loblolly pines (pinus taeda) years old, – cm in diameter, and spaced approximately m apart, comprised the dominant trees. the ‘mature’ forest was located directly across a dirt lane from the young forest. it, too, had been logged and managed for pine, but the pines were years old, – cm in diameter, and spaced approximately m apart. other tree species such as american holly, sweet gum, and southern red oak grew among the pines, as is typical for an older pine plantation in the area. in both forests, climate, soil type, and aspect were similar. d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e measuring the beauty of forests students rated the forests by placing a mark on the survey sheet along a cm line that was labelled ‘unattractive’ to the far left, ‘neutral’ in the centre, and ‘beautiful’ to the far right. no definition was given for the term ‘beauty’. students were simply asked to use their own personal definition. after viewing and rating the first forest stand students were led to the second forest stand directly across the road. in addition to rating the forests by marking the line, students were also asked which forest stand was more beautiful. answer choices were ‘the first one’, ‘the second one’, or ‘both were equal’. meanwhile the second group was taken inside the field station and given a -minute presentation on forest ecology and shown a few specimens of the tree species in the forest. the presentation made no reference to forest beauty or age, although many of the illustrating slides were taken in older forests. the presentation concentrated on the ecological function and ecological services provided by a forest (e.g. energy capture, carbon capture, habitat, improved stormwater quality, improved air quality, etc.). after the presentation this group was taken to the forest to complete the survey in the same manner as the first group. after the surveys were collected the marks were translated to numerical values by measur- ing the distance the mark fell along the line. in this manner ‘unattractive’ became equal to , ‘neutral’ became equal to , and ‘beautiful’ became equal to . three hundred and thirty-eight students visited the field station and completed the surveys. only four students were older than years and those four were dropped from the analysis to concentrate the demographic to – -year-olds, leaving for the final analysis; males and females. in an analysis of environmental perception rating scales schroeder [ ] determined that ‘in all cases the simple mean rating produced virtually identical results to the more sophisticated analyses’. consequently, i used mean ratings for all comparisons. data were normally distributed (kolmogorov-smirnov and shapiro-wilk) and the statistics package spss . was used for analysis. results when all ratings were combined the students rated the mature forest stand as being more beautiful than the young forest stand (figure ; paired t-test, p < . ). the mean rating for the mature forest was . (se = . ) putting it above neutral, while the mean rating for the young forest was . (se = . ) putting it below neutral. there were responses to the question that directly asked which forest was more beautiful. fifty students said they were both equal, chose the younger forest, and chose the mature forest. of the students who chose one forest over another in terms of beauty, % selected the young forest and % selected the mature forest. figure . males perceived the forest as more beautiful than the females when the mean of the combined ratings for both young and mature. differences are significant (p < . ). when all ratings were combined by gender, males and females showed no difference in the mean spread between ratings of the young and mature forests (males = . , females = . ; two-tailed t-test, p = . ), but males rated the forest as more beautiful overall (figure ; . vs . , se . and . respectively; two-tailed t-test, p < . ). the mean forest beauty rating for males was above neutral while the mean forest beauty rating for females was neutral. figure . the mature forest was rated as more beautiful than the young forest. differences are significant (p < . ). when the data were examined according to whether or not the students had seen the presentation before rating the forests (figure ), the ratings were higher after the presenta- tion for both the young ( . before presentation versus . after presentation) and the mature ( . before presentation, . after presentation) forest, but the differences were d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e j. maloof figure . the mature forest was rated as more beautiful than the young forest. differences are significant (p < . ). figure . males rated the forest higher in beauty than the females did (individual ratings for both young and mature forests were combined and the means were used for comparison. differences are significant p < . ). d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e measuring the beauty of forests not statistically significant (two-tailed t-test, p = . and p = . , respectively). again, both mean ratings were below neutral for the young forest and above neutral for the mature forest. figure . a presentation on forest ecology prior to viewing the forest stands made no significant difference in the ratings of the forests. in other studies no consistent differences were detected in scenic beauty estimates given by students and nonstudents [ ] therefore these figures are likely to represent the responses of a general population. discussion in aldo leopold wrote, ‘a thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. it is wrong when it tends otherwise’ [ ]. in the years since it was published this has become his most frequently quoted line. although many studies have attempted to measure the integrity and stability of biotic communities, far fewer studies have been focused specifically on measuring the beauty of the biotic community. consequently, we have no standardized tools used for measuring beauty, and no agreed method for comparing and communicating the attractiveness of various landscapes. despite this lack of quantification, the aesthetic qualities of natural areas are frequently mentioned as a reason for preserving them from development. but if aesthetic arguments are to be taken seriously in planning and policy-making then some level of objectivity and agree- ment is necessary. more studies are needed to quantify common responses to natural scenes. in this study i was able to show that % of the participants in a controlled study rated the mature forest as more beautiful than the young forest. this overwhelming agreement gives strength to the argument that there is a shared, objective, basis to the quality of beauty in the natural world. figure . a presentation on forest ecology prior to viewing the forest stands made no significant difference in the ratings of the forests. d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e j. maloof i found that the older forest was rated as more beautiful than the younger forest even though all other factors (terrain, soil type, climate, time of day) were similar. the mature forest was rated as above neutral and the young forest was rated as less than neutral in terms of beauty. overall, males rated the forest as more beautiful than females. most attempts at measuring nature aesthetics use photographs [e.g. , , ], but in this study the measurements were done in situ. visual perceptions are the most powerful determining factor in aesthetic preferences, but by measuring preferences in the actual envi- ronment more subtle perceptions such as sounds, smells, and even the feel of the soil beneath the feet, may be included in the ratings. although the methodology of this experi- ment is simple, this was a trade-off in return for the ability to test a large pool of subjects in situ. viewing a presentation about forest ecology immediately preceding the survey increased the ratings a small, but insignificant, amount. hence the ‘serious beauty’ hypothesis of the philosophers was not confirmed by my results. (the hypothesis states that the more one understands the natural world the more beautiful it will seem.) these results strengthen the argument that our aesthetic preferences are biologically based (and hence not capable of being readily changed) rather than knowledge- based (and thus likely to change depending on circumstances). these results indicate that knowledge of the forest ecosystem does not appre- ciably alter the perception of beauty. these results are similar to the findings of hill and davidson [ ] who found that varying the information that participants received about restoration decisions (some information favouring cleared areas and some information favouring forested areas) did not significantly alter the strong shared preferences for photographs of certain scenes. in this study the mature forest was selected as being more beautiful than the young forest. in effect, the subjects preferred the older forest. although this is not surprising, a quantifica- tion of this preference is important for environmental economists and policy-makers, who relate choice to value [ , ]. because older trees are preferred, they are more valuable than younger trees to the observer (in the currency of beauty); just as older trees are more valuable than younger trees to the logger (in the currency of money). given these circumstances we should expect conflicts between these two groups to increase as forests age, and to reach intense levels concerning the fate of mature forests. this study was conducted in a single young and a single mature forest stand in close prox- imity to one another, to reduce variables. the results could be strengthened by repeating it in other young and mature forests; and in other seasons. it is also possible that a lengthier course of study might influence the ratings. there is much more research which needs to be done regarding the beauty of nature. it would be interesting to learn why the forests were rated as more beautiful by the males than the females. is this a result of familiarity? of safety? or is it an inherent difference in the sexes? beyond the questions relating to our perceptions of beauty in nature, there are also questions that remain regarding the policy implications of our perceptions. the philoso- pher allen carlson notes that ‘an aesthetics of nature that cannot support grounds for preserving that which we find beautiful is not worthy of consideration’ [ ]. should beauty have a place in determining environmental policy? if we can say that one place is more beautiful than another, indeed, if it is more beautiful than most, or even all, other places are we then ethically obligated to preserve it? leopold would answer these questions in the affirmative, but more understanding of the thing we call beauty is needed before it can be used as a determining factor in land use decisions. this research is an exploratory step in that direction. d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e measuring the beauty of forests references [ ] daniel, t.c., , aesthetic preference and ecological sustainability, in: s.r.j. sheppard and h.w. harshaw (eds) forests and landscape: linking ecology, sustainability and aesthetics (new york: cabi), pp. – . [ ] brady, e., , aesthetics of the natural environment (tuscaloosa: university of alabama press). [ ] kaplan, r. and kaplan, s., , the experience of nature: a psychological perspective (cambridge: cambridge university press). [ ] preston, r., , scenic amenity: measuring community appreciation of landscape aesthetics at moggill and glen rock (brisbane: the state of queensland, department of natural resources and mines, environ- mental protection agency), isbn x. [ ] arthur, l.m., , predicting scenic beauty of forested environments: some empirical tests. forest science, ( ), – . [ ] schroeder, h.w. and daniel, t.c., , progress in predicting the perceived scenic beauty of forest land- scapes. forest science, ( ), – . [ ] brown, t.c. and daniel, t.c., , predicting scenic beauty of timber stands. forest science, ( ), – . [ ] panagopoulos, t., , linking forestry, sustainability and aesthetics. ecological economics, , – . [ ] garcia-rivera, a., graves, m. and neumann, c., , beauty in the living world. zygon, , – . [ ] usda (us department of agriculture, forest service), , landscape aesthetics: a handbook for scenery management: agriculture handbook number (washington, dc: usda).. [ ] sheppard, s.r.j., , visual analysis of forest landscapes, in: landscape and planning. (maryland heights, mo: elsevier). [ ] hill, d. and daniel, t.c., , foundations for an ecological aesthetic: can information alter landscape pref- erences. society and natural resources, , – . [ ] parsons, g., , aesthetics & nature (new york: continuum). [ ] carlson, a., , the requirements for an adequate aesthetics of nature. environmental philosophy, , – . [ ] kellert, s.r. (ed.), , the biophilia hypothesis (washington, dc: island press). [ ] schroeder, h.w., , environmental perception rating scales: a case for simple methods of analysis. envi- ronment and behavior, , – . [ ] leopold, a., ( ), a sand county almanac (oxford: oxford university press (new york: ballantine books)). [ ] van den berg, a.e., vlek, c.a. and coeterier, f., , group differences in the aesthetic evaluation of nature development plans: a multilevel approach. journal of environmental psychology, , – . [ ] pearce, d., markandya, a. and barbier, e.b., ( ), blueprint for a green economy (london: earth- scan publications). [ ] simpson, r.d., , david pearce and the economic valuation of biodiversity. environmental resource economics, , – . [ ] carlson, a., , nature & landscape (new york: columbia university press). d o w n l o a d e d b y : [ m a l o o f , j o a n ] a t : : j u n e doi: . /s - ( ) - r review modeling protein folding: the beauty and power of simplicity eugene i shakhnovich it is argued that simplified models capture key features of protein stability and folding, whereas more detailed models may be more appropriate for protein structure prediction. a brief overview of experimental and theoretical results is presented that corroborates these points. i argue that statistical models capture the key principle of protein stability — cooperativity — and therefore provide a reasonable estimate of protein free energy whereas more detailed but less physically transparent calculations fail to do so. i also explain that the previously published claim that simple models give predictions that are inconsistent with experiments on polypeptide block-copolymers is based on incomplete analysis of such experiments. address: department of chemistry, harvard university, oxford street, cambridge, ma , usa. e-mail: eugene@diamond.harvard.edu electronic identifier: - - -r folding & design june , :r –r © current biology ltd issn - the recent commentary by honig and cohen [ ] in folding & design discusses the role of different models in folding studies. such discussion is timely, because protein folding is a fascinating cross-disciplinary field that attracts scientists with different background and scientific cul- tures. they bring to the protein folding field the models and ways of thinking that are accepted in their respective background fields. such diversity of scientific cultures is a great virtue of the protein folding field, in which physics, chemistry, biology and mathematics meet. it is important for our cross-disciplinary field to discuss with balance both strong points and limitations of different approaches. to this end, the article by honig and cohen [ ] can be seen as a ‘nucleus’ for such a discussion in folding & design both on paper and on the internet (see the discussion pages on biomednet at http://biomednet.com/). unfor- tunately, as happens in many discussions, the commentary presents somewhat extreme views, minimizing the value of approaches based on simplified folding models. such an assessment does not seem to be substantiated by facts and by consistent analysis of recent developments. the purpose of my response is to present an alternative view- point based on experimental facts and theoretical analyses which show that simplified models have been a valuable tool for the study of folding. it is my hope that this response will present an account of successes and limita- tions of simplified models that is more balanced and respectful to all points of view. it is obvious that proteins are too complicated to allow exact modeling — some simplifications are necessary already at the stage of initial formulation of models. the crucial issue, common to any theoretical analysis, is where to draw ‘a line in the sand’, i.e. what degree of simplifica- tion is acceptable without ‘throwing the baby out with the bath water’. a useful model must exhibit folding in an unbiased simulation and, moreover, should allow for hun- dreds of folding events to occur. the latter requirement follows from the fact that folding is an intrinsically statisti- cal phenomenon and no conclusion can be derived from a single folding or unfolding trajectory. currently, folding simulations satisfying these important requirements are feasible only in the context of simplified lattice and off- lattice models (most of these are ‘sidechain-only’, in the terminology of [ ]; e.g. see [ – ] and references therein). it was suggested by honig and cohen [ ] that such “sidechain-only models fail to capture essential features of protein folding.” the existing gap between foldable and detailed atomistic models leaves us no choice other than to study folding mechanisms using simplified models, benchmarking them against experiment. after all, how should theory be judged? by its ability to explain existing experiments and to predict the results of future experiments. in this regard, contrary to the assertions of honig and cohen [ ], simpli- fied models provide valuable insights into the basic princi- ples of protein stability and folding. first of all, the lattice model captures one of the most fas- cinating and important features of proteins — cooperativ- ity of their structure [ , , – ]. contrary to a popular but incorrect view, helix/coil transition is not truly cooperative (not a first-order type, e.g. see [ ]). the reason for this is given by the landau theorem, which prohibits stable phases (such as one long helix) and phase transitions in one-dimensional systems without long-range (in space) interactions [ ]. this means that helix decay and formation cannot account for cooperativity of protein folding transition [ ]. a clear example is the non-cooperative character of unfolding of the molten globule state of myoglobin which involves massive helix breakdown but is non-cooperative [ ]. a virtue of simplified models is their intimate connection with statistical mechanics. this is very important, as it often allows us to compare simulation results with statisti- cal-mechanical analytical theories. as the two approaches (analytical and numeric) are often complementary (e.g. analytical theories require a large number of particles, whereas simulations often restrict it to modest values), the correlation between them brings more confidence in the validity of obtained results and allows us to get rid of arti- facts. an important example in this regard is the conver- gence of analytical theories and numeric simulations on the explanation of the basic reason for cooperative behav- ior as connected with the non-randomness of protein sequences, their optimization for efficient folding and higher stability [ , , , ]. random sequences were pre- dicted to exhibit noncooperative, diffuse transitions [ , , ]. this prediction has been confirmed by experi- ments [ , ]. lattice models capture the cooperative character of protein folding and therefore, in spite of their simplicity, they provide a reasonable estimate of generic protein sta- bility of . kcal m– residue– [ ], close to experimental values [ ]. this is a better estimate than calculations within a much more detailed ‘backbone-centric’ model, which in spite of a large number of parameters involved in many cases gives estimates of the free energy of folding more than an order of magnitude off from experimental values (see fig. c in [ ]). for example, calculations in [ ] estimate myoglobin stability to be greater than kcal m– while actually it hardly exceeds kcal m– at physiological conditions [ ]. this is not surprising because the protein free energy represents a small differ- ence between two large numbers — energetic contribu- tions (roughly kcal m– residue– ) and the opposing entropic contributions of the same order of magnitude. calculations that involve many parameters but fail to incorporate the key physics of folding — cooperativity — are not likely to have sufficient precision to give a reliable estimate of folding free energy of an individual protein. another important issue is how simplified models treat protein folding kinetics. the simplification introduced in many — but not all — lattice models is that they do not include backbone hydrogen bonds explicitly. is this factor crucial? clearly the impact of backbone hydrogen bonds on folding kinetics is essential only if they are formed, to a con- siderable extent, before folding transition state is reached. in this regard, honig and cohen [ ] refer to two papers [ , ] which concern unfolding intermediates. in their view, the results of these papers suggest that the transition state of unfolding “appears to be due to the breaking of hydrogen bonds”. i believe that this conclusion does not follow from the experiments reported by baldwin and co- authors [ , ]. what they actually show is that all hydro- gen bonds get disrupted at the rate-limiting step of unfolding, after the dry molten globule intermediate [ ]. that does not imply that hydrogen bonds break at or near the transition state. in fact, as transition from the dry molten globule unfolding intermediate to the unfolded state is two state, all properties change with the same kinetic exponent. therefore, it is impossible to judge from the experiments [ , ] at what point(s) of the unfolding trajectories overcoming the major barrier the disruption of hydrogen bonds occurs. independently of where each hydrogen bond does actually break in the rate- limiting step of unfolding, it will be decaying with the same kinetic exponent. currently, in fact, only the protein engineering method can provide information about the structure of the folding transition state [ ]. keeping that in mind, let me turn to the analysis of experiments that aim specifically to study the folding transition state. these clearly point out that the hydrogen bond network, or secondary structure, is formed after the folding transition state is overcome. first, consider a series of conclusive experiments by fersht and co-workers on ci [ , ]. they provide extensive data suggesting that mutations outside the nucleation core (but affecting the stability of secondary structure) do not signif- icantly affect folding kinetics. a good example is val →ala substitution in ci . mutation of two neighbor- ing core residues belonging to the same �-helix, ala and ile , strongly affect folding kinetics having �-values of . and . respectively. val does not participate in the core but belongs to the �-helix. its mutation to alanine stabilizes the helix [ ], but leads to only a % increase of the folding rate (practically within experimental error). normalized to a small stability change, it yields a �-value of – . for val [ , ]. this shows clearly that the con- tribution of formation of transient fragments of secondary structure to folding rate is a few percent. the conclusive result of simulations and protein engineer- ing experiments is that the major factors determining folding kinetics are long-range (in sequence) interactions forming the nucleus [ , ]. these results are corrobo- rated in the work of sauer and co-workers [ ] with another protein, p arc repressor. mutation pro →leu increased the stability of the �-sheet, but the folding rate remained largely unchanged. the conclusion was made in this work [ ] that “the �-sheet forms after the rate-limit- ing state in folding.” subsequent study from the same lab- oratory [ ] included substitution of many helical sites in the p arc repressor by helix-propensity altering alanine with little change in folding rates also. similar results were obtained recently for another protein, chey [ ]. for example, mutation gly →ala in this protein stabilizes �-helix but does not affect the folding rate (�-value for folding is . ). mutational analysis was also employed by sosnick et al. [ ] to determine when secondary structure forms in the folding of an �-helical dimer, gcn . residues at non-per- review modeling protein folding shakhnovich r r folding & design vol no turbing positions along the exterior length of the helices were substituted one at a time with alanine and glycine to vary helix propensity. for all variants the bimolecular folding rate remains largely unchanged; the change in sta- bility appears largely in the unfolding rate. sosnick et al. [ ] conclude that “contrary to most folding models, wide- spread helix is not yet formed at the rate-limiting step in the folding pathway.” theoretical efforts in the framework of simplified lattice [ ] models lead, along with experiments [ , ], to the discovery of the nucleation-condensation mechanism via formation of a specific nucleus in the folding transition state. this mechanism is likely to capture important fea- tures of folding kinetics of at least small proteins. further, analysis of lattice model kinetics allowed us to develop a successful approach to predict the residues which consti- tute the folding nucleus [ ], i.e. making even very spe- cific predictions of the theory testable experimentally. finally, i analyze the ‘gedanken experiment’ interpreted by honig and cohen [ ] as a convincing proof of the serious limitations of lattice models. honig and cohen discuss experiments of scheraga and co-workers [ ] on conformational transition in polyalanine. alanine is a mod- erately hydrophobic helix-stabilizing amino acid. accord- ing to honig and cohen [ ] “polyalanine, hn, forms an �-helix, but is predicted by sidechain-only models to form an array of compact structures” (h stands for hydropho- bic). i was quite intrigued by this conclusion because it did not sound to be consistent with statistical mechanics. indeed, helical conformation in this case is unfavorable energetically as well as entropically. compaction into glob- ular state with high helical content could result in both enhanced hydrophobic interactions and entropy increase due to a multitude of available compact conformations. some details of the experiments of scheraga and co- workers [ ] were not clearly explained by honig and cohen. reading the original paper, i found the following. in order to make their polymers soluble, scheraga and co- workers [ ] attached long charged polylysine ‘tails’ to both ends of the polyalanine. in salt-free solution, where coulomb repulsion between polylysines is unscreened and overwhelming, the central fragment, polyalanine, indeed adopts extended helical conformation. when salt is added, the repulsion between polylysine tails is screened and polyalanine adopts a compact globular conformation with high helical content. it is clear that the attached polylysine plays a crucial role in determining the confor- mation of the polyalanine fragment. it also explains why longer polyalanine helices in [ ] are more stable. short polyalanine fragments force polylysine tails to come close to each other. repulsion between polylysine fragments destroys polyalanine helix forcing the chain into extremely extended conformation. longer polyalanine sequences experience less stretching force from the polylysine tails and, although they still cannot become compact in salt-free solution, they can become helical. most lattice models of folding do not include long-range (in space) coulomb forces, the reason being that in most cases folding occurs at physiological salt concentrations, at which electrostatic forces are screened. long helices without chain compaction were observed in [ ] in salt- free solution. a trivial modification of a lattice model to account for such conditions would be to introduce coulomb interactions between charged monomers. then a fair comparison with lattice models would be to consider a poly-h sequence with very strong unscreened coulomb repulsion between the ends. such a lattice chain, under the action of stretching force between the ends, will adopt an extended conformation. simple addition of local i,i+ attraction makes this extended conformation helical if the chain is long enough to keep the ends sufficiently far from each other. this corresponds to the salt-free case of the experiment [ ]. when the repulsion between chain ends diminishes (upon addition of salt in [ ]), hydrophobic attraction takes over and the chain becomes compact in the lattice model, in agreement with basic statistical mechanics and the experiment [ ]. moreover, when local i,i+ attrac- tion (modeling hydrogen bond) is added along with hydrophobic attraction in the lattice model, the resulting lattice conformations were shown to be compact and helical (see fig. a in [ ]), exactly like the ones in the high-salt case in the experiment [ ]. summarizing the dis- cussion of the ‘gedanken experiment’, i note that, opposite to the claim of honig and cohen [ ], the results of this elegant study of scheraga and co-workers [ ] are consis- tent with statistical mechanics and can be rationalized within simple lattice models. in fact, a statistical-mechani- cal rationale for the observed effects was given already in the original paper [ ]. it will be a matter of interest in future study to model block-copolymer polypeptides like the ones studied by scheraga and co-workers [ ]. lattice and other simplified analytical models are the sta- tistical mechanician’s contributions to protein folding. it is part of the culture in this field to appreciate that simpli- fied models provide coarse-grained descriptions and as such they may be adequate to describe the effects taking place on longer (than microscopic) time and length scales. the most important example of this kind is folding, and i have presented evidence here that statistical-mechanical models do capture many essential features of folding. certainly such models have their limitations. many impor- tant effects, such as protein function or ligand binding specificity, occur on microscopic length and time scales. lattice models do not provide a sufficient degree of detail to study these phenomena. their analysis requires all- atom models and molecular dynamics simulations [ ]. besides that, there are a number of aspects of folding that are more microscopic in nature for which lattice models, in their present form, can have problems. one example is proline isomerization, which is known to prevent folding if proline isomers are incorrect. other issues are chirality of amino acids and tight packing of sidechains. these aspects of the folding problem can be addressed in the framework of more atomistic models, which are currently not feasible for folding simulations. it is also possible that more detailed models are needed to address the second, more visible to the public, side of the ‘holy grail’ of protein folding — prediction of protein con- formation. conclusive successes in that direction may be for the distant future, despite considerable progress achieved in the elucidation of the folding mechanism. this situation has many analogies with other fields of physics or chemistry where models often adequately tackle fundamental large-scale behavior but do not capture all microscopic properties. one example of this kind is that although crystallization as a physical phenom- enon is understood, we are still unable to predict crystal symmetry from the chemical structure of the constituting molecules. i believe that it is indeed important to 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( ). proteins: a theoretical perspective on dynamics, structure and thermodynamics. wiley, new york. r folding & design vol no discussion pages relevant to this article are now available from the folding & design gateway page within the biomednet at http://biomednet.com/cbiology/fad.htm econstor make your publications visible. a service of zbw leibniz-informationszentrum wirtschaft leibniz information centre for economics darai, donja; grätz, silvia working paper facing a dilemma: cooperative behavior and beauty working paper, no. provided in cooperation with: department of economics, university of zurich suggested citation: darai, donja; grätz, silvia ( ) : facing a dilemma: cooperative behavior and beauty, working paper, no. , university of zurich, department of economics, zurich, http://dx.doi.org/ . /uzh- this version is available at: http://hdl.handle.net/ / standard-nutzungsbedingungen: die dokumente auf econstor dürfen zu eigenen wissenschaftlichen zwecken und zum privatgebrauch 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cooperative behavior and beauty donja darai and silvia grätz revised version, december university of zurich department of economics working paper series issn - (print) issn - x (online) facing a dilemma: cooperative behavior and beauty∗ donja darai and silvia grätz† december , abstract this paper investigates the influence of physical attractiveness on cooperative be- havior. we survey data from episodes of a television game show and combine it with independent facial attractiveness ratings of the show’s contestants. the fi- nal of the show represents a simultaneous one-shot modified prisoner’s dilemma. our results show that facially attractive contestants provoke cooperative behavior from their counterparts, but attractive contestants themselves do not behave dif- ferently from unattractive ones. this preferential treatment or “beauty premium” rewards attractive contestants with substantially higher monetary gains of up to £ . this finding applies to both sexes. but, the attractiveness effect is limited to mixed-gender interactions. contestants are only more cooperative when facing an attractive fellow player of the opposite sex. attractiveness also has no effect in group-decisions made by the contestants prior to the prisoner’s dilemma. therefore people seem to show a preference to cooperate with someone towards whom they are personally attracted; and this preference reaches full effect when people lack other information on which to base their decision. keywords: beauty premium, cooperation, prisoner’s dilemma jel classification: c , d , z ∗the authors thank ulrich kaiser, armin schmutzler, michelle sovinsky, roberto weber, the seminar participants at the university of zurich and florida state university, the participants at the esa inter- national meeting in new york (u.s.), the workshop on behavioral economics mainz (germany), the zurich workshop on economics in luzern (switzerland), and the esa european meeting in cologne (germany) for helpful discussions and suggestions, as well as pascal kappeler, christina richard, and holger scriba for excellent research assistance. financial support of the swiss national science foundation is gratefully acknowledged. the data on “golden balls” were provided to the authors by the television show producers, courtesy of endemol uk plc, in may . †both authors, department of economics, university of zurich, donja.darai@econ.uzh.ch, silvia.graetz@econ.uzh.ch “all that glitters is not gold; often have you heard that told.” william shakespeare, merchant of venice ( - ) introduction beginning with the seminal paper of biddle and hamermesh ( ), which identifies a wage gap based on physical attractiveness using labor market data of the u.s. and canada, economists started to be interested in the effects of physical attractiveness on economic de- cision making. for instance, mobius and rosenblat ( ) show that the beauty premium for attractive people is even present in a controlled laboratory labor market experiment. eckel and petrie ( ) provide evidence that people have a willingness to pay for being able to see a picture of their counterpart before making their decision in a trust game, suggesting that valuable information is conveyed by the physical appearance of people. however, the transmission channel of the effect of physical attractiveness on economic decision making is still only partly understood. the most prominent theory is “beauty-is- good” stereotyping. people assign a wide range of positive personality traits and abilities to physically attractive people. that is, people believe that physically attractive people are, for instance, more trustworthy, more likable, and more productive (see e.g., dion, berscheid, and walster ( )). these beliefs then alter people’s behavior towards at- tractive people. however, not all that glitters is gold. there is only very limited evidence that the “beauty-is-good” stereotype is accurate. this paper studies the relationship between attractiveness and cooperative behavior and shows that the beauty premium is also present in a high-stakes field setting with two-sided communication and previous interaction between players. our results offer an alternative explanation of the effects of attractiveness on economic decision making. we suggest a preference based transmission channel in the sense that people’s behavior is biased when facing someone attractive of the opposite sex. we confirm our hypothesis with existing experimental data from mobius and rosenblat ( ). specifically, this paper combines two independent data sets. first, to study cooperation, we survey data from episodes of the british television game show “golden balls”, in which the show’s finalists play for a jackpot at the end of the show. the rules of this game follow a slightly modified version of a simultaneous one-shot prisoner’s dilemma: if both contestants choose to cooperate, the jackpot is split equally; if one chooses to defect while the other cooperates, the former receives the entire jackpot and the latter gets nothing; if both defect, they both go home empty-handed. the accumulation of the jackpot takes place in two rounds of pre-play previous to the prisoner’s dilemma and requires neither the contestants’ effort nor cognitive ability. on average, the stake size is £ indicat- ing that decisions in the prisoner’s dilemma have substantial distributional consequences for the contestants. during the two rounds of pre-play, the two finalists are selected out of four initial contestants. second, we collect data on the contestants’ facial appearance from a sample of independent raters. these raters are asked to evaluate portrait photographs of the contestants along various dimensions such as physical attractiveness, sympathy, trustworthiness, or likability. we provide evidence that physical attractiveness affects cooperative behvaior. contestants of the show are significantly more cooperative towards a facially attractive opponent than towards a facially unattractive opponent, independent of gender, age, other demographic characteristics, stake size, and communication. facially attractive contestants are there- fore awarded with significantly higher earnings in the prisoner’s dilemma. quantifying this beauty premium, a one-standard deviation increase in facial attractiveness, at the margin, causes the contestant’s expected earnings to rise by up to £ , as well as the contestant’s probability to obtain positive earnings by up to . percentage points. this effect is not driven by non-cooperative behavior of the attractive. with minor qualifica- tions for younger and female contestants, we find no correlation between a contestant’s own facial attractiveness and cooperation. although the attractiveness effect likewise applies for men and women, we show that it is limited to mixed-gender interactions only. contestants are only biased in their decision to cooperate when facing an attractive opponent of the other sex. thus, the attractiveness effect is not present in same-gender interactions. this finding offers a new perspective on the underlying mechanism of the effects caused by attractiveness. our results are not driven by people believing that attractive others are more likely to cooperate, but rather by people having a preference to cooperate more with someone towards whom they are personally attracted to. furthermore, we cannot identify a beauty premium or plainness penalty during the pre-play, which clearly supports our conjecture that personal attrac- tion serves as the underlying transmission channel of physical attractiveness on people’s behavior in pairwise interactions and that attractiveness matters most when objective information is missing. to validate our results, we repeat the analysis of mobius and rosenblat ( ) and un- cover that their identified effects of attractiveness disappear when we parse their data by the composition of sex, that is, when we consider interactions between employers and workers of the same sex separately from those of the opposite sex. again, “beauty-is-good” stereotyping fails to consistently explain the findings. therefore, we offer an alternative mechanism underlying the attractiveness effects, namely a “preference-driven” mechanism. physical attractiveness mediates people’s behavior, because people want to behave differ- ently towards someone whom they feel personally attracted to. the remainder of this paper is structured as follows. in section we discuss related literature. section describes the data sets and section presents the results. potential transmission channels are evaluated in section . finally, section concludes. literature a long history of research on physical attractiveness in psychology, sociology, and evo- lutionary biology and a more recent one in economics and political science shows that physically attractive people are or behave not substantially differently from physically unattractive people, but that physically attractive people receive a preferential treatment by others in many regards. this “beauty premium” rewards attractive people with sub- stantially higher monetary gains or greater economic success. surprisingly, the mechanism underlying the effect of physical attractiveness is still not completely uncovered. the most prominent theory, established in sociology and psychology, is that people link beauty and positive personality traits. in particular, people attribute a variety of positive characteristics and higher abilities to physically attractive people, and negative ones to physically unattractive people (see reviews by eagly, ashmore, makhijani, and longo ( ), feingold ( ), and langlois, klakanis, rubenstein, larson, hallam, and smoot ( )). this is referred to as “beauty-is-good” stereotyping in the literature. the theory argues that stereotype beliefs cause people to treat attractive ones more favorably, and this in turn results in higher economic gains for the attractive. hence, beauty-is-good stereotyping can explain why attractive people generally fare better in the labor market, i.e., why they are more likely to be hired, promoted, and earn higher salaries. in their sem- inal work biddle and hamermesh ( ) use a broad household survey of the u.s. and canada and show that physically attractive employees earn about - percent more than less attractive employees, independent of their occupation. in an experiment on the effects of beauty in experimental labor markets, mobius and rosenblat ( ) find that attractive employees are awarded higher wages, although they are not more productive than unattractive employees, measured by a real-effort task. this suggests that employers hold (inaccurate) stereotypical expectations about the performance of physically attrac- tive employees. ruffle and shtudiner ( ) explore the value of beauty in the hiring process, examining response rates to cvs sent to companies in israel. they uncover a gender-specific effect of attractiveness, namely a beauty premium for males, and a beauty penalty for females. in their pioneering study, dion, berscheid, and walster ( ) claim “what is beautiful is good” by demonstrating that attractive people are believed to have better career prospects, to possess socially desirable traits, to lead happier lives and to be happier overall. this paper spawned a large literature on the physical attractiveness stereotype, demonstrating for both sexes a robust association between physical attractiveness and cognitive ability, competence, sociability, popularity, dominance, sexual experience, mental health, and social skills. also, research in political science shows that physical attractiveness has a significant im- pact on the evaluation of candidates and thereby on electoral outcomes (see the survey by ottati and deiger ( )). for instance, attractiveness increases the candidate’s number of votes and thereby the likelihood of being elected (berggren, jordahl, and poutvaara ( ) and rosar, klein, and beckers ( )). antonakis and dalgas ( ) suggest that underlying the effect of physical attractiveness is the voters’ belief that attractive can- didates are more competent. recruiting adults and children raters in switzerland, they find that even children can predict results of the french parliamentary election ret- rospectively by rating the competence of the candidates from their photographs. furthermore, the theory of beauty-is-good stereotyping in combination with interdepen- dent social preferences can explain findings in various experimental settings with strategic interactions. these findings suggest that people behave more generously or cooperatively towards physically attractive people. solnick and schweitzer ( ) show that attractive responders receive significantly higher offers than unattractive responders in the ultima- tum game. in dictator games, rosenblat ( ) shows that allocators treat physically and vocally attractive recipients more generously. andreoni and petrie ( ) observe a beauty premium in a repeated public goods game, which is not caused by lower contri- butions of attractive players, but can be attributed to an increase of the other players’ contributions triggered by an attractive group member. in a repeated trust game, wilson and eckel ( ) demonstrate that attractive trustees are trusted more and that players expect attractive players to be more trustworthy than unattractive ones. the failure to meet these expectations leads to a beauty penalty. mulford, orbell, shatto, and stockard ( ) examine a repeated prisoner’s dilemma, pointing out that players are more coop- erative if matched with an attractive partner. in contrast to the other studies, they use attractiveness ratings based on the perception of the player who also makes the decision in the experiment, rather than ratings elicited from independent third-party judges. however, all above mentioned studies provide only very limited evidence for the accuracy of the beauty-is-good stereotype. physically attractive people themselves do not behave differently than physically unattractive people. besides the theory of stereotyping based upon peoples’ visual attractiveness, zuckerman and driver ( ) and zuckerman, hodgins, and miyake ( ) proclaim the existence in another experimental study on the trust game, eckel and petrie ( ) investigate the informa- tional value of a photograph and the differential desire to acquire this information. subjects are willing to pay to see the photograph of their partner whom they transact with, indicating that a face has a positive informational value which is used to discriminate between players in their choices. jackson, hunter, and hodge ( ) show in their meta-analysis that there is a modest correlation between attractiveness and intelligence for children. mueller and mazur ( ) use data from a cohort of military officers and find that recruits with a high ranked facial appearance are also high ranked in their physical fitness. concerning social skillfulness and likability, goldman and lewis ( ) and erwin and calev ( ) find that physically attractive people indeed possess better social skills and are more likable. of a vocal attractiveness stereotype by showing that physical attractiveness is positively correlated with vocal attractiveness. supporting a vocal-attractiveness mechanism, mo- bius and rosenblat ( ) find that the beauty premium even exists in treatments in which employers are able to talk to the employee without seeing the employee’s picture. rosenblat ( ) provides evidence that physically attractive people only achieve signifi- cantly better outcomes in dictator games when the dictator sees the recipient’s picture in addition to hear her pre-recorded voice. this suggests voice to be one of the transmission channels of the beauty premium, at least in two-sided communication settings. finally, one of the oldest and most well-known theories underlying the effects of attrac- tiveness is the one of taste-based discrimination, proposed by becker ( ). physically attractive people are favored because people enjoy being or working with them more than with plain looking people. discrimination is based upon prejudices correlated with peo- ple’s personal characteristics and is rational in the sense that interactions with such a person generate a (dis)utility for the discriminator in case of positive (negative) discrimi- nation. belot, bhaskar, and van de ven ( ) find that attractive contestants of a dutch television game show are positively discriminated against unattractive ones in proceeding to the final stage of the show. however this theory fails to explain why attractive people are also treated more favorably in one-shot interactions. summarizing, in line with the literature we expect physically attractive people to obtain a beauty premium in the one-shot prisoner’s dilemma. physically attractive people will be favored by others in the sense that people show greater cooperativeness towards them. but physically attractive people themselves will not behave differently compared to physically unattractive people. data . the television game show “golden balls” we analyze people’s behavior in a simultaneous one-shot prisoner’s dilemma of episodes of the british television game show “golden balls”. the dilemma is played in the final in particular attractive contestants are much more likely to reach the final round of the show, even though they are not performing better or are not more confident than unattractive contestants. perfor- mance in this show means being the first to correctly answer trivia questions. attractive contestants are believed to be more confident and to be more cooperative. besides, at the end of the show a prisoner’s dilemma – like the one we study – is played. belot, bhaskar, and van de ven ( ) also test for effects of attractiveness on cooperative behavior, however they find no significant effects. we suspect that the reason why they are not able to identify any attractiveness effects is that their sample of finalists becomes too homogeneous with regard to attractiveness, due to the selection bias towards attractive contestants during the pre-play. the game show was aired in june and ended in december . we use records of episodes of the first four series of the show. round of the show to allocate the jackpot between the two finalists: each player is assigned two balls, indistinguishable from the outside, but one contains the word “steal” and one contains the word “split”. both contestants choose one of their two balls and then open it simultaneously. if both choose the split-ball (cooperation), the jackpot is split equally; if one chooses the steal-ball (defection) while the other chooses the split-ball (cooperation), the former receives the entire jackpot and the latter gets nothing; if both choose the steal- ball (defection), they both go home empty-handed (see figure ). thus, defection is a weakly-dominant strategy. figure : prisoner’s dilemma game split (cooperate) steal (defect) split (cooperate) / jackpot , / jackpot , jackpot steal (defect) jackpot , , note: defection is a weakly dominant strategy before the prisoner’s dilemma is played, the contestants have to pass two rounds of pre- play. in these rounds, the finalists are selected and the jackpot is accrued. accumulating the jackpot does not require contestant’s cognitive ability or effort. on average, the jack- pot amounts to £ and ranges from a minimum of £ to a maximum of £ . the two finalists are selected through two voting decisions. after each round, the contestants need to cast a vote against one of them to leave the show. the contestant who receives the majority of votes is eliminated. throughout the show the contestants face each other and are allowed to freely communicate with each other (see supplementary material for a detailed description of the game show). table a. in the appendix presents summary statistics of the outcomes of the prisoner’s dilemma and of the contestants’ personal characteristics. the unilateral cooperation rate is %, and contestants mutually cooperate (defect) in % ( %) of cases. % of finalists are male and the mean age is years. . survey on facial appearance we evaluate the contestants’ facial appearance using a panel of independent raters. the raters are recruited at the euro-airport basel, at the university of zurich, and at the each pre-play round, the contestants are randomly assigned a certain cash value. for the detailed description of the show, see online appendix. university of zurich for the elderly. all contestants are judged by raters and, from those, raters judge the finalists. each rater was asked to individually rate the facial appearance of five randomly assigned contestants, of which two or three were male (female). on average, a finalist is judged by . raters. table i reports summary statistics for the finalists’ raters and table a. in the appendix for all contestants’ raters. the mean age of the raters is years and % are male. table i: summary statistics of the finalists’ raters rater’s variable mean std. dev. min. max. n male . . age (in years) . . age of male (in years) . . age of female (in years) . . age of female (≥ . years) . . age of female (< . years) . . age of male (≥ . years) . . age of male (< . years) . . the survey is questionnaire based. for an illustration of a sample questionnaire see fig- ure . each questionnaire contains two portrait photographs of the same contestant and is divided into three parts. to receive non-biased evaluations of the contestants and to reduce measurement error, all photographs are selected from the same two sequences of the game show such that one photograph shows a neutral facial expression with a view to the camera and the other a neutral facial expression with a view to the side of the camera. in the first part of the questionnaire, the raters are asked to judge the contestant with respect to her age by fitting the contestant into one of seven age categories, “< ”, “ - ”, “ - ”, “ - ”, “ - ”, “ - ”, or “> ” years. the second part includes assessments of the contestant’s appearance using four opposite word pairs, i.e., “attractive - unattrac- tive”, “likable - unlikable”, “trustworthy - untrustworthy”, and “honest - dishonest”. these items are rated on a -to- point likert scale, where equals very unattractive, com- prises a neutral position and equals very attractive. in the last part of the questionnaire we asked the raters to give a binary response (yes/no) to two statements: “this person’s appearance helps him/her in life” and “this person strikes me as calculating”. these state- ments are included to capture a rater’s overall impression of the respective contestant’s the university of zurich provides lectures for a senior audience, that are mainly attended by retired people. we only recruited raters who either had a very high proficiency or were native speakers of german, french, or english and provided the questionnaires in the respective language. if possible we chose a neutral facial expression of the contestant, otherwise a positive one was chosen, but never a negative or disadvantageous one. the use of a -point likert scale, which includes a neutral element, allows for sufficient diversification and is standard in the relevant literature, see e.g., alreck and settle ( ), pp. - . appearance, i.e., whether a contestants is either attributed a beauty premium or a strate- gic intention per se. figure : sample questionnaire . evaluation of facial appearance ratings the raters’ evaluations are used to construct a facial appearance measure for each of the four items: attractiveness, honesty, likability, and trustworthiness. we account for rater specific variation in the perception of the respective appearance item in the construction of each measure. for each rater j we calculate the average across all contestants rated by j, x̄j. then we mean-center the ratings by subtracting the respective rater’s mean rating, x̄j, from her individual rating of contestant i, xij. these demeaned ratings are raters may differ in the interpretation of the -point scale, and may vary in anchoring their average rating above, below or close to . student t-tests of differences between the means of the facial appearance measure by the raters’ gender are: t = . , p = . for attractiveness, t = . , p = . for likability, t = . , p = . for trustworthiness, and t = . , p = . for honesty. this shows that female raters tend to give higher ratings than male raters. this phenomenon is also persistent with respect to the raters’ age. further, it is known that images of females tend to be rated higher than images of males, see e.g., jackson, hunter, and hodge ( ) and wilson and eckel ( ). since we control directly for gender-related effects in the regressions, the attractiveness measure can be used uncorrected for the gender of the contestants. as a robustness check we construct a measure by making use of the rater-specific fixed effects, rather than correcting for them. in particular, we attach higher weight to ratings made by raters that are similar to the contestant with respect to age and gender, and we attach lower weight to ratings made by raters that are unsimilar to the contestant. all results remain unchanged. now anchored at for each rater and are therefore corrected for rater-specific fixed effects (see figure a. in the appendix). finally we take the mean of all mean-centered ratings of contestant i, resulting in the particular facial-item measure for each contestant. [facial-item]i = ej[xij − x̄j] with { i = i-th contestant j = j-th rater additionally, we construct two variables from the binary statements “appearance helps in life” and “appearance strikes as calculating” by taking the mean rating for each con- testant. in the following we refer to these variables as “statement variables”. table ii provides summary statistics of all appearance measures. table ii: summary statistics facial appearance variable mean std. dev. min. max. n attractiveness (mean-centered, cont.) . - . . honesty (mean-centered, cont.) . - . . likability (mean-centered, cont.) . - . . trustworthiness (mean-centered, cont.) . - . . appearance helps in life (cont.) . . appearance strikes as calculating (cont.) . . all four facial appearance variables are highly positively correlated (see table iii). this is also reflected in a sufficiently high cronbach coefficient alpha (α = . ). table iii: correlation matrix for facial appearance variables, n= attractiveness honesty likability trustworthiness helps in life attractivenessa honesty . ∗∗∗ likability . ∗∗∗ . ∗∗∗ trustworthiness . ∗∗∗ . ∗∗∗ . ∗∗∗ helps in lifeb . ∗∗∗ . ∗∗∗ . ∗∗∗ . ∗∗∗ strikes as calculating . − . ∗∗∗ − . ∗∗∗ − . ∗∗∗ . a mean-centered, continuous variables (for attractiveness, honesty, likability, trustworthiness). b averaged, continuous variables (for “appearance helps in life”, “appearance strikes as calculating”). again, there may be differences between the means of the statement variables’ ratings by the raters’ gender. student t-tests w.r.t. gender are t = . , p = . for “appearance helps in life” and t = − . , p = . for “appearance strikes as calculating”, i.e., male raters are more likely to rate a contestant as calculating than female raters. we use cronbach’s alpha for standardized variables to measure the inter-item reliability for facial appearance. the measure adjusts for item specific mean and variance. also a nonparametric test for testing whether samples originate from the same distribution cannot be rejected (kruskal-wallis k = . ). the statement variable “appearance helps in life” is also positively correlated with all four facial appearance variables. however, the statement variable “appearance strikes as calculating” is not correlated with attractiveness, and even negatively correlated with the remaining facial appearance variables. in the following, we focus on facial attractiveness, since it is a crucial part of the first impression of a person and a stable characteristic which is almost impossible to mimic (see e.g., grammer, fink, møller, and thornhill ( )). the two statement variables are used as additional controls. there are many ways to define an attractive person. we use the following classifications: first, we classify a contestant as facially attractive if her facial attractiveness rating lies above or is equal to the mean over all facial attractiveness ratings, and as facially unattrac- tive if her facial attractiveness rating lies below this mean. the average mean-centered rating of facially attractive contestants is . , and the one of facially unattractive con- testants is − . . we also used the median over all facial attractiveness ratings as a classification device. the average mean-centered rating of a facially attractive contestant, who is rated above or equal to (below) the median is . (− . ). second, we define extreme measures of facial attractiveness. a contestant is classified as most attractive if her facial attractiveness rating lies within the top % ( %) percentile of the distribution of facial attractiveness and as least attractive if her facial attractiveness rating lies within the bottom % ( %) percentile. contestants who are rated as most attractive receive, on average, a mean-centered rating of . ( . ), and those who are rated as least attractive receive a mean-centered rating of − . (− . ). for an illustration of the distribution of facial attractiveness see figure a. in the appendix. table iv: summary statistics facial attractiveness variable mean std. dev. min. max. n attractiveness (mean, d) . . attractiveness (median, d) . . most attractive ( % percentile, d) . . most attractive ( % percentile, d) . . least attractive ( % percentile, d) . . least attractive ( % percentile, d) . . helps in life (d) . . strikes as calculating (d) . . (d) for dummy variable. third, we define a contestant’s appearance to be helpful in life (to strike as calculating ) if her “helps in life”-rating (“strikes as calculating”-rating) lies above or is equal to the mean over all “helps in life”-ratings (“strikes as calculating”-ratings), and as not to be helpful in life (not to strike as calculating ) if her “helps in life”-rating (“strikes as calculating”- rating) lies below this mean. table iv summarizes the binary attractiveness and statement variables. a detailed description of the distribution of attractive and unattractive finalists with respect to gender and age is provided by table a. in the appendix. results . facial attractiveness in order to investigate the relationship between cooperative behavior and facial attractive- ness we use several binary probit models with the decision to cooperate as the dependent variable (with yi = equal cooperate; yi = equal defect). throughout the analysis, we control for effects and interactions related to the contestant’s gender and age, other demographic characteristics, as well as variables of stake size, communication, and vari- ables describing the course of events of the game show previous to the prisoner’s dilemma (pre-play), see table a. in the appendix. own attractiveness the results depicted in table v, model ( ) to ( ), show that facially attractive contestants do not behave differently with respect to cooperativeness than facially unattractive contestants, independent of the specification of the attractive- ness measure. this finding is in line with our conjecture from the literature (see e.g., eagly, ashmore, makhijani, and longo ( )): physically attractive people are not more pro-social and therefore not more cooperative than physically unattractive people. whereas, overall, we find no difference between the cooperative behavior of attractive and unattractive people, there are some qualifications with respect to gender and age. both gender and age seem to mediate the effect of a contestant’s own attractiveness on table v reports the regression results including a dummy variable for the attractive contestant. for robustness of all our results, we also estimate the regressions including (i) the continuous measure for attractiveness, (ii) the mean over the four appearance variables, (iii) the predicted factors obtained in a confirmatory factor analysis of the four appearance variables, (iv) a normalized attractiveness measure in line with mobius and rosenblat ( ), in which our constructed attractiveness measure is normalized across all contestants, (v) a normalized attractiveness measure in line with biddle and hamermesh ( ), in which the normalization is across all raters, and (vi) the mean and median attractiveness ratings of the raw data, where the mean (median) is . ( . ) with an average rating of facially attractive contestants above the mean (median) of . ( . ), and below the mean (median) of . ( . ). all measures produce qualitatively the same results. irrespective of a contestant’s own attractiveness, we find a very strong and significant correlation between age and cooperative behavior (see table v): older contestants (≥ years) are much more likely to cooperate than younger contestants (< years), regardless of the age of the opponent. this result is in line with list ( ) who finds that contestants ≥ years are significantly more likely to cooperate than younger contestants. concerning gender, we find no direct effect, which is contrary to the studies of e.g., kahn, hottes, and davis ( ) and ortmann and tichy ( ). but we can show that younger males are significantly more likely to defect; and, as age increases, males are more likely to cooperate than females (see table a. in the appendix). cooperation, see table a. in the appendix. attractive females (model ( )) and attrac- tive younger contestants (model ( )) show more cooperative behavior, whereas attractive males (model ( )) and attractive older contestants (model ( )) cooperate less. opponent’s attractiveness we now turn to the impact of the opponent’s facial at- tractiveness on a contestant’s willingness to cooperate. the regression results in table v show that contestants are − percentage points more likely to cooperate when facing an attractive opponent than when facing an unattractive opponent. hence, attractive contestants are rewarded with greater cooperativeness, and this provides attractive con- testants a beauty premium. the premium is independent of the opponent’s gender and age, see table a. , model ( ) and ( ) in the appendix. furthermore, our results show that least attractive contestants suffer a beauty penalty due to lower cooperativeness towards them. as model ( ) reports, a contestant is less likely to cooperate if the opponent is rated to be least attractive than if the opponent is neither rated to be most nor least attractive. there is no significant effect on cooperative behavior if the opponent is rated to be most attractive. the result holds independently of the definition of the extreme measure of attractiveness. these findings suggest that contestants rather focus on the opponent’s “negative” than “positive” appearance in the decision to cooperate. the results remain unchanged when adding the two binary statement variables (see model ( ) of table v). there is additional evidence that a contestants is less likely to cooperate if the opponent’s appearance is rated as to “help her in life” than if it is not. but we find no interaction effect of the binary statement variables and our attractiveness mea- sures, which indicates that the statement variables have not much additional explanatory power. similarity since contestants behave more cooperatively towards the attractive counter- part, the question arises whether pairs of attractive contestants behave differently in the prisoner’s dilemma than pairs of unattractive contestants or pairs who are mixed in terms of facial attractiveness. we denote pairs of contestants as similar team if either both contestants are facially attractive or both are facially unattractive, and we identify pairs of contestants as an attractive team if both are facially attractive, and as an unattractive team if both are facially unattractive. we find no evidence that contestants who are sim- ilar with respect to attractiveness are more or less likely to cooperate or defect, see model ( ) of table a. in the appendix. however, we find that an unattractive contestant is less likely to cooperate with her unattractive counterpart compared to teams of contestants note, the effect of the variable “the contestant’s appearance helps her in life” without the inclusion of the facially attractiveness variables is positive, but not significant. we also tested for interaction effects between the two statement variables and gender or age (table unreported). we find that a female opponent, whose appearance is rated as helping her in life, lowers the contestant’s propensity to cooperate; but this effect is not robust with respect to different specifications of the model. t a b le v : r es u lt s fr o m b in a ry p ro b it re g re ss io n s o f th e d ec is io n to “ co o p er a te ” (y i = ) o r “ d ef ec t” (y i = ) in th e p ri so n er ’s d il em m a m a rg in a l e ff e c ts m o d e l ( ) m o d e l ( ) m o d e l ( ) m o d e l ( ) m o d e l ( ) a tt ra c ti v e n e ss (m e a n -c e n te re d , d ) (d ) . ( . ) . ( . ) . ( . ) . ( . ) o p p o n e n t a tt ra c ti v e n e ss (m e a n -c e n te re d , d ) (d ) . ∗ ∗ ( . ) . ∗ ∗ ( . ) . ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) a p p e a ra n c e h e lp s in l if e (d ) . ( . ) . ( . ) o p p o n e n t a p p e a ra n c e h e lp s in l if e (d ) - . ∗ ( . ) - . ( . ) a p p e a ra n c e s tr ik e s a s c a lc u la ti n g (d ) . ( . ) . ( . ) o p p o n e n t a p p e a ra n c e s tr ik e s a s c a lc u la ti n g (d ) - . ( . ) . ( . ) m o st a tt ra c ti v e ( % p e rc e n ti le ) (d ) - . ( . ) o p p . m o st a tt ra c ti v e ( % p e rc e n ti le ) (d ) - . ( . ) l e a st a tt ra c ti v e ( % p e rc e n ti le ) (d ) - . ( . ) o p p . le a st a tt ra c ti v e ( % p e rc e n ti le ) (d ) - . ∗ ∗ ∗ ( . ) m a le (d ) - . ( . ) - . ( . ) - . ( . ) - . ( . ) - . ( . ) a g e (c o n t. ) . ∗ ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) o p p . m a le (d ) - . ( . ) o p p . a g e (c o n t. ) . ( . ) p ro m is e o r v o w (d ) . ∗ ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) . ∗ ∗ ∗ ( . ) o p p . p ro m is e o r v o w (d ) . ( . ) - . ( . ) - . ( . ) h a n d sh a k e (d ) - . ∗ ( . ) - . ( . ) - . ∗ ∗ ( . ) d e m o g r a p h ic s – x x x x s t a k e s iz e – x x x x p r e -p la y – – x x x w a ld χ . ∗ ∗ ∗ . ∗ ∗ ∗ . ∗ ∗ ∗ . ∗ ∗ ∗ . ∗ ∗ ∗ l o g -l ik e li h o o d - . - . - . - . - . a d ju st e d r . . . . . n n u m b e r o f c lu st e rs s ta n d a rd e rr o rs in p a re n th e se s a re c o rr e c te d fo r e p is o d e c lu st e rs ; * p < . , * * p < . , * * * p < . (d ) fo r d is c re te ch a n g e o f d u m m y v a ri a b le fr o m to who are both attractive or mixed, see model ( ) and ( ) of table a. in the appendix. this improves our attractiveness-results: contestants not only behave more cooperatively towards an attractive partner, but also more deceitfully towards an unattractive partner, and this unattractive-penalty is likely to dominate. thus, our results provide evidence for a causal relationship between the opponent’s at- tractiveness and cooperative behavior. facially attractive contestants are able to provoke cooperation from their counterpart, independent of their gender or age. but we do not find a significant difference in behavior between facially attractive and facially unattractive contestants. . beauty premium the results of the previous section should also translate into a monetary beauty premium, i.e., into higher earnings for the attractive than for the unattractive. in order to quantify the marginal beauty premium we use a standard censored tobit model. the outcome “taking no money home” from the prisoner’s dilemma is interpreted as a corner solution outcome, where the response variable yi describes the observable outcome of a contestant, which takes on the value zero with positive probability (if the opponent defects), and which is a continuous variable over strictly positive values (if the opponent cooperates). we estimate marginal effects for contestant i’s expectation of receiving positive earnings yi > , conditional on i’s own and her opponent’s facial attractiveness (standardized mea- sures), demographic characteristics, the log value of the stake size, as well as opponent characteristics, which are summarized in xi, e(yi|xi,yi > ). we find that a one standard deviation increase in facial attractiveness significantly in- creases a contestant’s expected positive earnings by £ to £ depending on the controls included, see table a. in the appendix. figure provides an illustration of the beauty premium based on model ( ) of table a. in the appendix, and depicts the predicted positive earnings for attractive and unattractive contestants as a function of stake size. the figure shows that the predicted earnings of facially attractive contestants are always clearly above the earnings of unattractive contestants, given the size of the jackpot. decomposing the beauty premium with respect to gender and age, we can show that there are no differences in receiving positive earnings between attractive male and female, for robustness of our results, we repeat the analysis using ordered probits on the contestants’ likeli- hood to mutually cooperate. again, similar teams, as well as teams of attractive contestants are no more likely to reach a certain outcome. only pairs of unattractive contestants are significantly less likely to reach mutual cooperation (tables unreported). additionally, we estimate regressions including the relative difference between both final contestants’ attractiveness, i.e., the distance in attractiveness between both contestants, and including an index of the contestants’ similarity with respect to facial attractiveness, age, and gender, weighting each component by one-third. all measures do not matter for the contestant’s figure : predicted positive earnings by attractive and unattractive contestants, given stake size pr ed ic te d ea rn in gs stake size % ci attractive unattractive as well as attractive older and younger contestants. however, a contestant’s expected earnings increase the older the opponent, and a contestants expected earnings decrease when the opponent is male (see model ( ) of table a. in the appendix). transmission channels our results show that attractive people are able to provoke cooperative behavior from their opponent and, since they are not more or less cooperative than unattractive people, they obtain a beauty premium in the prisoner’s dilemma. in this section we will address the potential transmission channels suggested by the literature (see section ) and evaluate their explanatory content for our observed effects of attractiveness. . beauty-is-good stereotyping and taste-based discrimination the most prominent theory is that people hold stereotype beliefs about attractive people. people believe that attractive ones behave more pro-socially than less attractive ones. in the presence of interdependent social preferences, people may belief that attractive ones are more cooperative and behave more cooperatively towards them with the intention to reciprocate cooperation. hence, these stereotype beliefs can mediate people’s behavior. recall, however, that we do not find any difference between attractive and unattractive contestants regarding their likelihood to cooperate. if “beauty-is-good” stereotyping is decision to cooperate. we obtain a similar result for the overall conditional expectation that a contestant receives the outcome yi, given xi, e(yi|xi). a one standard deviation increase in facial attractiveness significantly increases a contestant’s expected earnings by £ to £ . further, we estimate that the probability of obtaining positive earnings, given xi, pr(yi > )|xi), increases by up to . percentage points (tables unreported). driving our result, then we should observe a higher likelihood of cooperation towards at- tractive contestants in the prisoner’s dilemma and the effect should be independent of the selected sample, e.g., the effect should be present in interactions between contestants of the same sex as well as between contestants of the opposite sex. however, theories from evolutionary psychology argue that effects of physical attractive- ness on behavior originate in primeval partner selection and therefore predict that effects of attractiveness are more prevalent in mixed-gender interactions (see e.g., cosmides and tooby ( )). to scrutinize this argument, we parse the data in mixed-gender and same-gender interactions ( % and % of all interactions) and run several probits to evaluate the influence of facial attractiveness on a contestant’s propensity to cooperate, controlling for demographic characteristics and stake size. the two subsamples are not different regarding the observed cooperation rate ( % in mixed- vs. % in same-gender interactions, see table vi). table vi: results from binary probit regressions on outcomes in the prisoner’s dilemma (subsamples) marginal effects ( ) mixed-gender ( ) same-gender attractiveness (mean-centered, d) . ( . ) . ( . ) opp. attractiveness (mean-centered, d) . ** ( . ) . ( . ) male (d) - . ( . ) - . ( . ) age (cont.) . ** ( . ) . *** ( . ) demographics x x stake size x x wald χ . *** . * log-likelihood - . - . adjusted r n . . number of clusters . . note: binary probit regressions of the decision to “cooperate” (yi = ) or “defect” (yi = ) in the prisoner’s dilemma, restricting the sample to ( ) mixed-gender and ( ) same-gender interactions. the marginal effect of the respective explanatory variable determines the effective change of this variable on player i’s predicted probability to “split”. standard errors are reported in parentheses and are corrected for episode clusters. * p < . , ** p < . , *** p < . as the regression results of table vi show, attractiveness only matters in mixed-gender interactions, but not in same-gender ones. males and females are about % percentage points more likely to cooperate if facing a facially attractive opponent of the other sex than if they face an unattractive opponent. the finding applies across sexes, both fe- males and males are biased towards attractiveness if facing someone of the other sex. this this result is also displayed in the fact that facially attractive contestants enjoy a beauty premium in mixed-gender interactions, but not in same-gender ones (tobit regression tables unreported). a one standard deviation increase in attractiveness results in a significantly higher gains for the attractive in mixed-gender (p= . ), but not in same-gender interactions (p= . ). extends the finding of ashmore and longo ( ), who note that only attractive females tend to have the ability to make males more likely to do them a favor. we show that males have the same ability. according to the theory of taste-based discrimination (becker ( )), contestants might favor to be in the final round with a facially attractive fellow player. hence, taste-based discrimination could be the underlying mechanism if we identify a beauty premium in the pre-play, but not in all interactions in the prisoner’s dilemma. using binary and ordered probit models, we estimate the effect of attractiveness on the likelihood to be voted off the game and on the likelihood to receive a certain number of votes after the first and second round. we find no significant effect of attractiveness on the voting outcome (tables unreported). this is also reflected in the almost equal share of attractive contestants in the final and the one in the initial round of the game show ( . % vs. . %). the absence of a beauty premium or plainness penalty in the pre-play and in same-gender interactions in the final suggests that neither beauty-is-good stereotyping nor taste-based discrimination can explain our results consistently. it rather seems that the ability of attractiveness to mediate behavior is entangled to the opponent’s sex and that people have a preference to cooperate with someone to whom they are personally attracted. . vocal attractiveness and social skills in addition to the theories discussed above, the literature reports that physical and vocal attractiveness are highly correlated and thus suggests the existence of a vocal rather than a visual attractiveness stereotype (see, e.g., zuckerman and driver ( )). furthermore, physically attractive people are also assigned stronger verbal and social skills (e.g., gold- man and lewis ( ) and erwin and calev ( )). in the presence of other regarding preferences, vocal attractiveness and potentially strong verbal and social skills might en- able attractive people to trigger cooperative behavior off their opponents. although our data does not allow us to directly test for the impact of (perceived) vocal attractiveness on cooperative behavior, we can indirectly test for a correlation between facial attractiveness and communication which comprises verbal and social skills. shortly before the prisoner’s dilemma is played both contestants are given some extra time to talk to each other. in these short conversations which are, on average, seconds long, each contestant tries to convince her opponent to cooperate. since it has been shown that in all regressions we control for demographic characteristics such as gender, age, race and place of residence as well as for objective voting criteria such as the stake size a contestant accumulated, and whether a contestant lied in a previous round of the pre-play. we also follow belot, bhaskar, and van de ven’s approach and rank the contestants by their facial attractiveness to explain the likelihood to be voted off during the game, which yields no significant effects either (table unreported). our finding is in contrast to belot, bhaskar, and van de ven ( ), who find that attractive people are positively discriminated against unattractive people and hence pass the pre-play more easily. promises effect people’s behavior in experiments (e.g., charness and dufwenberg ( ) and vanberg ( )) and in the field (e.g., belot, bhaskar, and van de ven ( )), we code whether a contestant explicitly promises her opponent to cooperate. furthermore, we observe that contestants use handshakes to corroborate their mutual intention to co- operate and therefore we also code whether two contestants shake hands. as table v shows, promises have a significantly positive impact on cooperative behavior, whereas handshakes have a negative one. comparing models ( ) and ( ) of table v shows that the effect of attractiveness on cooperation remains almost unchanged when we add the variables of communication as controls. if attractive contestants are better in terms of verbal and social skills, a promise or hand- shake of a facially attractive contestant might be more convincing than a promise or handshake of a facially unattractive contestant. testing for interaction effects between facial attractiveness and the communication variables, reveals no additional effects (table unreported). further, we could expect that facially attractive contestants are more likely to elicit a promise from their opponent and less likely to engage in a handshake. using binary probit regressions on the contestant’s propensity to promise or to shake hands, we find that facially attractive contestants are not more likely to state a promise or to shake hands than facially unattractive contestants (table unreported). however, we find limited evidence that contestants are significantly more likely to state a promise if the opponent is attractive (table unreported). since promising to cooperate significantly increases a contestant’s likelihood to cooperate, we cannot exclude that promises are the underlying transmission channel of facial attractiveness on cooperative behavior. the absence of the beauty premium in the pre-play can also not be explained by the theory of better social and verbal skills or vocal attractiveness. conclusion this paper analyzes the relationship between attractiveness and cooperative behavior in a high-stakes field setting with two-sided communication. two independent data sets are combined. one on cooperation, collected from decisions made in a slightly modified prisoner’s dilemma played in the final round of a television game show. the other one on the physical attractiveness of the game show’s contestants using a sample of indepen- we count all statements as a promise when they contain either the word ”promise” or ”swear” or they are a statement of intent. examples are ”i promise to split”, ”i promise i will not steal”, ”i swear i will split”, ”i swear i will not steal”, ”i will split”, or ”i will not steal”. the effect of the communication variables is robust to various specifications of the regression model. including only demographics, the likelihood to cooperate of a contestant who made a promise to co- operate is percentage points (p= . ) higher than the one of a contestant who did not promise to cooperate. when contestants use a handshake they are actually percentage points (p= . ) less likely to cooperate than when they do not use a handshake (table unreported). dent third-party raters. in the prisoner’s dilemma two finalists play for an accumulated jackpot by deciding either to “split” the jackpot or to “steal” it and to keep the entire amount for themselves. the results show a strong and robust effect of attractiveness: contestants are significantly more likely to cooperate with a facially attractive opponent. but, facially attractive contestants are not more or less likely to be cooperative com- pared to facially unattractive contestants. hence, attractive contestants are rewarded by a beauty premium, which, at the margin, amounts to up to £ for an increase in attractiveness of one standard deviation. the attractiveness effect is robust to demo- graphic characteristics, including gender, stake size, and communication. however, the effects of attractiveness might be amplified by the attractive contestant’s ability to talk their opponent into promising to cooperate, which has a significantly positive effect on a contestant’s likelihood to cooperate. however, the decomposition of the data into same- and mixed-gender interactions reveals a new picture. the ability of attractive contestants to elicit cooperative behavior from their opponent vanishes in interactions between two contestants of the same sex. that is, contestants are only biased by the facial attractiveness of their opponent when the op- ponent is of the other sex. this suggests that stereotype beliefs about attractive people, such as them being more pro-social, cannot explain our results. since for this explanation to hold, the effect should prevail in all interactions. in line with our finding are rather theories from evolutionary psychology arguing that effects of physical attractiveness origi- nate in primeval partner selection and should therefore be only or at least more present in mixed-gender interactions (see e.g., cosmides and tooby ( )). also, the absence of a beauty premium or plainness penalty in the pre-play suggests that physical appearance is particularly important as soon as people are lacking objective information and moreover it allows us to exclude taste-based discrimination as the underlying transmission channel of attractiveness on cooperative behavior. to confirm our hypothesis of a preference based mechanism, we test it with the data from mobius and rosenblat’s experiments on the beauty premium in the labor market. the authors argue that stereotype beliefs about attractive people’s productivity and the higher confidence of attractive people in their own productivity are driving the results. attractive people earn significantly higher wages even though they do not display a higher productivity than unattractive people. we re-estimate mobius and rosenblat’s full model (table , p. in mobius and rosenblat ( )) parsing the data into mixed- and same- gender interactions. the results are presented in table a. in the appendix. as predicted by our hypothesis the effects of attractiveness remain only prevalent in interactions be- tween either a female worker and a male employer or a male worker and a female employer (model ( )). in model ( ) which uses the sample of same-gender interactions, all effects of attractiveness disappear. our results are relevant and applicable to many, if not all, one-shot face-to-face inter- actions. the better performance of attractive people in the labor market, for instance, may be enforced by the fact that they also benefit from greater cooperativeness towards them. and facing someone attractive of the other sex seems to bias people when making economic decisions, which may help beautiful people in negotiations when cooperation is required. references alreck, p. l., and r. b. settle ( ): the survey research handbook. chicago: irwin. andreoni, j., and r. petrie ( ): “beauty, gender and stereotypes: evidence from laboratory experiments,” journal of economic psychology, , – . antonakis, j., and o. dalgas ( ): “predicting elections: child’s play!,” science, , . ashmore, r. d., 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( =“steal-steal”, =“steal-split”, =“split-split”) amount money taken home . . demographics male . . agea(cont.) . . . age of male (cont.) . . . age of female (cont.) . . . . white . . london . . england ( = eng, = sco, wal, nir, irl) . . social job (reputation)b . . unexperienced (contestants of series ) . . experienced (contestants of series ) . . stake size jackpot . . potential jackpotc . . communication promise or vow . . handshake . . pre-play accumulated most money . . selected higher values in bin/win . . selected most killers in bin/win . . “should have left the game”d . . lied during pre-play . . a age is judged on a -item scale (see questionnaire and section . ), where =“ - ”, and =“ - ” implying that the scale average of . equals a mean age of years. b a social job is defined as a job in which people care for other people, e.g., doctors, nurses, child minders, social workers, teachers, police officers, firemen, soldiers. c the potential jackpot is announced by the show host before the actual jackpot is determined. it displays the maximal amount the actual jackpot could potentially comprise of. d the variable “should have left the game” points at the player who is the “weakest” in material terms in round . figure a. : raw [left] and demeaned [right] variables of facial appearance, n= attractive honest likable trustworthy − − − attractive honest likable trustworthy table a. : summary statistics all raters variable mean std. dev. min. max. n age (in years) . . age of male (in years) . . age of female (in years) . . male . . female (≥ . years) . . female (< . years) . . male (≥ . years) . . male (< . years) . . table a. : distribution of attractive and unattractive finalists facially attractive facially unattractive male (< years) % % male (≥ years) % % female (< years) % % female (≥ years) % % % (n= ) % (n= ) t a b le a . : r es u lt s fr o m b in a ry p ro b it re g re ss io n s o f th e d ec is io n to “ co o p er a te ” (y i = ) o r “ d ef ec t” (y i = ) in th e p ri so n er ’s d il em m a , in cl u d in g th e in te ra ct io n te rm “ g en d er * a g e” m a rg in a l e ff e c ts m o d e l ( ) m o d e l ( ) m o d e l ( ) m o d e l ( ) m o d e l ( ) a tt ra c ti v e n e ss (m e a n -c e n te re d , d ) . ( . ) . ( . ) . ( . ) o p p . a tt ra c ti v e n e ss (m e a n -c e n te re d , d ) . * * ( . ) . * * * ( . ) . * * * ( . ) a p p e a ra n c e h e lp s in l if e (d ) . ( . ) . ( . ) . ( . ) o p p . a p p e a ra n c e h e lp s in l if e (d ) - . ( . ) - . * ( . ) - . ( . ) a p p e a ra n c e s tr ik e s a s c a lc u la ti n g (d ) . ( . ) . ( . ) . ( . ) o p p . a p p e a ra n c e s tr ik e s a s c a lc u la ti n g (d ) . ( . ) . ( . ) . ( . ) m o st a tt ra c ti v e ( % p e rc e n ti le , d ) - . ( . ) o p p . m o st a tt ra c ti v e ( % p e rc e n ti le , d ) - . ( . ) l e a st a tt ra c ti v e ( % p e rc e n ti le , d ) - . ( . ) o p p . le a st a tt ra c ti v e ( % p e rc e n ti le , d ) - . * ( . ) m a le * a g e (c o n t. ) . * * ( . ) . * ( . ) . * ( . ) . ( . ) . * ( . ) m a le (d ) - . * * ( . ) - . * ( . ) - . * ( . ) - . ( . ) - . * ( . ) a g e (c o n t. ) . ( . ) . ( . ) . ( . ) . * ( . ) . ( . ) o p p . m a le (d ) - . ( . ) o p p . a g e (c o n t. ) . ( . ) p ro m is e o r v o w (d ) . * * * ( . ) . * * * ( . ) o p p . p ro m is e o r v o w (d ) - . ( . ) - . ( . ) h a n d sh a k e (d ) - . ( . ) - . * ( . ) d e m o g r a p h ic s x x x x x s t a k e s iz e x x x x x p r e -p la y – – – x x w a ld χ . * * * . * * * . * * * . * * * . * * * l o g -l ik e li h o o d - . - . - . - . - . a d ju st e d r . . . . . n n u m b e r o f c lu st e rs s ta n d a rd e rr o rs in p a re n th e se s a re c o rr e c te d fo r e p is o d e c lu st e rs ; * p < . , * * p < . , * * * p < . (d ) fo r d is c re te ch a n g e o f d u m m y v a ri a b le fr o m to t a b le a . : r es u lt s fr o m b in a ry p ro b it re g re ss io n s o f th e d ec is io n to “ co o p er a te ” (y i = ) o r “ d ef ec t” (y i = ) in th e p ri so n er ’s d il em m a , in cl u d in g in te ra ct io n te rm s w .r .t . g en d er a n d a g e m a rg in a l e ff e c ts m o d e l ( ) m o d e l ( ) m o d e l ( ) m o d e l ( ) a tt ra c ti v e n e ss * m a le (d ) - . * ( . ) o p p . a tt ra c ti v e n e ss * m a le (d ) . ( . ) a tt ra c ti v e n e ss * a g e (c o n t. ) - . * * ( . ) o p p . a tt ra c ti v e n e ss * a g e (c o n t. ) - . ( . ) a tt ra c ti v e n e ss (m e a n -c e n te re d , d ) . * ( . ) . * * ( . ) o p p o n e n t a tt ra c ti v e n e ss (m e a n -c e n te re d , d ) . ( . ) . ( . ) m a le (d ) . ( . ) - . ( . ) - . ( . ) o p p . m a le (d ) - . ( . ) a g e (c o n t. ) . * * * ( . ) . * * * ( . ) . * * * ( . ) o p p . a g e (c o n t. ) . ( . ) d e m o g r a p h ic s x x x x s t a k e s iz e x x x x w a ld χ . * * * . * * * . * * * . * * * l o g -l ik e li h o o d - . - . - . - . a d ju st e d r . . . . n n u m b e r o f c lu st e rs s ta n d a rd e rr o rs in p a re n th e se s a re c o rr e c te d fo r e p is o d e c lu st e rs ; * p < . , * * p < . , * * * p < . ; (d ) fo r d is c re te ch a n g e o f d u m m y v a ri a b le fr o m to table a. : results from binary probit regressions of the decision to “cooperate” (yi = ) or “defect” (yi = ) in the prisoner’s dilemma when teams of contestants are considered marginal effects model ( ) model ( ) model ( ) similar team (d) - . ( . ) attractive team (d) . ( . ) . ( . ) unattractive team (d) - . ** ( . ) - . * ( . ) male (d) - . ( . ) - . ( . ) - . ( . ) opp. male (d) - . ( . ) age (d) . *** ( . ) . *** ( . ) . *** ( . ) opp. age (d) - . ( . ) demographics x x x stake size x x x pre-play & communication – – x wald χ . *** . *** . *** log-likelihood - . - . - . adjusted r . . . n number of clusters note: the “team variables” are indicators and equal if the team is so composed and otherwise, e.g., “similar team” equals if both contestants are either attractive or unattractive, and otherwise. standard errors are reported in parentheses and are corrected for episode clusters. * (p < . ), ** (p < . ), *** (p < . ) table a. : censored tobit regressions results for e[yi|xi,yi > ] marginal effects model ( ) model ( ) attractiveness (standardized) . ∗ ( . ) . ∗∗ ( . ) opp. attractiveness (standardized) . ( . ) male (d) - . ( . ) - . ( . ) age (cont.) - . ( . ) - . ( . ) opp. male (d) - . ∗ ( . ) opp. age (cont.) . ∗∗∗ ( . ) log(jackpot) . ∗∗∗ ( . ) . ∗∗∗ ( . ) demographics x x opp. demographics – x f-statistic . *** . *** log-likelihood - . - . adjusted r . . σ̂ . . n number of clusters note: censored tobit regression for the conditional expectation, that player i receives a positive earn- ings yi > from the prisoner’s dilemma game: e[yi|xi,yi > ] = xiβ + σ [ φ(xiβ/σ) Φ(xiβ/σ) ] , where the in- verse mills ratio is evaluated at xiβ σ . the marginal effect for the jth independent (continuous) variable on e[yi|xi,yi > ] is computed as mej = ∂e[yi|xi,yi> ] ∂xj = βj [ − φ(xiβ/σ) Φ(xiβ/σ) ( xiβ σ + φ(xiβ/σ) Φ(xiβ/σ) )] , and quantifies the expected increase in earnings, conditional on being positive. (d) for discrete change of dummy variable from to . standard errors are reported in parentheses and are corrected for episode clusters. * p < . , ** p < . , *** p < . table a. : fixed effects regression of mobius and rosenblat ( ) model ( ) model ( ) model ( ) all interactions mixed gender same gender (table , p. ) interactions interactions lnprojected . ∗∗∗ ( . ) . ∗∗∗ ( . ) . ∗∗∗ ( . ) lnprojected*visual . ( . ) . ( . ) . ( . ) lnprojected*audio - . ∗∗ ( . ) - . ( . ) - . ( . ) lnprojected*visual*audio . ( . ) - . ( . ) . ( . ) lnprojected*ftf - . ( . ) . ( . ) . ( . ) lnactual - . ( . ) - . ∗ ( . ) . ( . ) beauty - . ( . ) - . ∗ ( . ) . ( . ) beauty*visual . ∗∗ ( . ) . ∗∗ ( . ) - . ( . ) beauty*audio . ∗∗∗ ( . ) . ∗∗ ( . ) . ( . ) beauty*visual*audio - . ∗ ( . ) - . ∗ ( . ) . ( . ) beauty*ftf . ( . ) . ( . ) . ( . ) lnestimated . ( . ) . ( . ) . ( . ) lnestimated*visual . ( . ) - . ( . ) . ( . ) lnestimated*audio . ∗∗∗ ( . ) . ( . ) . ( . ) lnestimated*visual*audio - . ( . ) . ( . ) - . ( . ) lnestimated*ftf - . ( . ) . ( . ) - . ∗∗ ( . ) f-statistic . ∗∗∗ . ∗∗∗ . ∗∗∗ r . . . n note: significance levels: ∗ p < . , ∗∗ p < . , ∗∗∗ p < . . the dependent variable is lnwage, standard errors are in parentheses. the base university is university .the regression includes the following resume controls: demographic variables (sex, age and age squared, internet at home, participation in team sports, choice of college major, hobby variables, and previous job market experience). the regression also includes setwage, and setwage interacted with beautyand lnestimated. cameron tonkinwise "we love the beautiful with frugality and knowledge without softness."[ ] this famous phrase from pericles' funeral oration is often considered foundational for the western way of living which is now dominating the world. it is supposed to signal the interrelated projects of science and art in a secular world. westerners, rejecting or losing any sense of the transcendent (i.e., gods), set about cultivating motivating rituals through disciplined economies of beauty. the modern world is born of people striving for non-transcendental beauty in things, in ideas, in everyday ways of living. the classic expression of the legacy of pericles' phrase is the romanticism of german idealism, and friedrich schiller's the aesthetic education of man in particular. here, science and art are unified by a secular faith in the motivating power of beauty - bi/dung, aesthetic formation, the ability of the beautiful to lead (e-duce) humans toward individual and collective excellence. recent work, by philippe lacoue-labarthe and jean-luc nancy for example [ ] argues that this myth of the immanently transcendent power of beauty has stalled. the 'bootstrapping' that the romantic project, as the modern heir to pericles' edict, hoped to accomplish, has been interrupted. beauty, far from empowering formative change, remains as the merely pleasing (which etymologically refers to pacifying, rendering silent, f attening).[ ] all that we have left, apart from the occasional violent attempt to re-enforce an aesthetic politics, [ ] are the ruined vestiges of art in a world of eco-technics (which jean-luc nancy defines as never- finished housework, purely technical and economic, utterly fractured and meaningless ).[ ] clearly, this hiatus in the e-motiveness of beauty has not been realised by many advocating 'ecological politics'. failing to heed baudrillard's warnings about the distracting appropriation of aesthetics by late capitalist sign economies, [ ] many ecologists, especially biocentric deep ecologists, still believe that the aesthetics of nature are inherently moralising.[ ] even when imitated by artificial products and environments, such beauty, they hope, can change people's values and therefore their behaviours.[ ] i would like briefly to explore this issue by way of an exercise that the ecodesign foundation often sets tertiary design students. following the short brief in italics is a list of responses that tend to emerge as students work in groups. design a tea cup that can and will be used every day for at least years. "it would have to be made out of stainless steel, aluminium, titanium. "some new type of nano-level fused super-strength ceramic. or a smart material filled with small bubbles of unsolidified plastic that break open to initiate self-repair when the cup is fractured. "maybe a shock-absorbing synthetic rubber, so that the cup bounces rather than breaks. "good ergonomics would also lessen the chance of the cup being dropped. so, finger-sized indentions, non-slip grips, tight-fitting strap-on handles. "come to think of it, most cups are broken when washing up, not when drinking. so perhaps a washing device needs to be designed as well as the cup, one that delicately handles the cup in slippery cleaning conditions. "in which case, why not create an entire device that automatically handles the cup at every stage (extraction, filling, drinking, cleaning, drying, restoring). it would be one of those intricate mechanical devices that cartoonists always create, from heath robinson to wallace and grommit; a machine that removes fallible humans from the process altogether, apart from imbibing. after all, a 'cup' is just a beverage delivery system. "perhaps that's going too far. not a very pleasant way to drink tea after all. "which reminds us; aesthetics. this cup better be nice if it's going to be around for a century. and not just good looking, but nice to use. "maybe that's the trick to the brief, the thing in the problem-statement that is always missed on the too-quick first read through: "a cup that can and will be used every day." not just: somebody will use this cup everyday, but: somebody will want to use this cup everyday. "so, it's got to be a 'design classic', timeless. simple, yet elegant - that's the usual formula. what have been the 'classic cups' to date? are there any year old cups around still in use? "the old cups that are still around are bone china, and, what's more, most are as thin as paper. "aha. a cup that can and will be used everyday for at least years will be not just beautiful, but beautifully fragile. it will not be robust at all. its beautiful fragility will encourage humans to take care of it, handling it with more sensitivity than any automated system ever could. "yet it won't be reifyingly beautiful, the sort of thing that sits on a mantelpiece. its beauty will draw humans to use it despite its fragility. it will be beautiful to use, so beautiful-in-use that it will become the centre of a secular ritual, a tea ceremony, passed from generation to generation. "and in this way, each use will enhance its useful beauty, reinforcing its value as an heirloom, strengthening its beauty, and therefore adding layers of care to its use that will compensate for its unavoidably increasing fragility." if you can imagine a decreasing log scale down the page, this would be an indication of how far students get in half an hour; most make it half-way, very few make it to the end. on most occasions, when the teacher offers the final 'ritual solution' to the class, the move from robustness to fragility comes as a surprising gestalt switch to the students. as always, some are delighted, others feel like they have been tricked by the ambiguity in the briefs wording in a time- pressured situation. ecodesign foundation educators tend to use the exercise as a way of suggesting to designers that their capabilities and responsibilities extend beyond the design of things to the design of relations between humans and things. whether they are conscious of it or not, designers do have the power to influence how people relate to things. design semantics constrain, map and afford not just the instrumental use of what is designed, but how the designed is perceived and valued. [ ] designers can, do and should design patterns of behaviour like rituals of care.[ ] they cannot design these in the way they specify materials and components, but they do, every time they design, emphasise, promote, and foster certain practical dispositions toward what they have designed.[ ] the context for this argument is that there is no such thing as a sustainable product or built environment, only more sustainable uses of products and built environments. unsustainability derives from the way we relate - or more accurately, fail to relate - to the things we use everyday. this is why a design awarded for its sustainability can be used in utterly unsustainable ways.[ ] the exercise points designers to the sustainability that comes from the reduced material flows that accompany longer product use-lives.[ ] it is part of on ongoing research project called decadesign, which works from the assumption that there is almost no product that should have a use-life of less than a decade. whilst this is technically feasible, the barriers are almost always cultural.[ ] so the exercise is designed to demonstrate to designers that they cannot be excused from responsibility for the variables of use in the life-cycle of damage to sustainability associated with any product. there is no regulatory, educational or technological panacea to deal with these 'attitudes', so designers must begin to play their powerful part, especially if this means changing general cultural trends (such as those associated with the misnomers like 'maintenance free', 'disposable', 'cheap' and 'convenient'). this polemic is not unique to the ecodesign foundation.[ ] ezio manzini for some time has been advocating what could be called design-for-care; most recently he has proposed 'diy+' maintainability.[ ] his vision of a 'garden of objects', [ ] each tended for longer service-life, continues to inspire the anthropologically inventive work of eternally yours.[ ] manzini's leadership in this regard takes up earlier proposals in other contexts by abraham moles (the comprehensive guarantee - extended producer responsibility avant la lettre) [ ] and christopher alexander (repair-as-transformation for a timeless way of building).[ ] if moles lays the foundation for advocations of product-service systems,[ ] where responsibility for extended service life is designed into an expert business (possibly deskilling users, enhancing their dependence and perhaps their irresponsibility),[ ] alexander's more craft-like sensibility draws attention to the importance of enabling user participation in the lengthening product life.[ ] how then to cultivate user participation in more sustainable product-lives? the 'solution' to the one hundred year cup exercise argues that one way of designing care relationships between users and what they use is: beauty. two philosophical problems face the designers who take up this task of designing the sort of beauty-in-use that will design users into the sustainers of all those designed products that sustain them. very quickly: first, the sort of platonism that instituted design - techne as the projection of an eidos-morphe-telos separated out from, and placed before, and at the head of, the actual work of making - is also the platonism that privileges the idea over its earthly, temporal manifestation.[ ] in this (un)worldview, [ ] things may be beautiful, but their beauty is exactly what shines out above their material existence. beauty is metaphysical; exactly what inspires us to turn away from the vita activa of everyday life and toward contemplation of the truly eternal.[ ] for plato, beauty could never cultivate a desire to labour at the preservation, restoration or transformation of things. apart from having their origin in this same distinction between things and their projection, designers tend to still get their aesthetic education from the contemplation of museumed objects, silhouetted out from their background everyday life, and recast in the ethereal neutrality of the photographic studio. when all sense of aesthesis as the experience of things is lost beneath the hegemony of vision, then designers are ill-equipped to design what was called in the tea cup protocol above, beauty-in-use. second, modern senses of beauty have their foundations in kant's third critique. what is pleasing, according to kant, is useless purposefulness.[ ] we call beautiful what we each believe everybody should acknowledge as perfect, complete.[ ] we take pleasure, from a disinterested distance, in finalities. that such beauties appear to have been made by an expert is exactly why it is impossible to think that they would need more making, or remaking.[ ] the beautiful needs no sustenance; it is anorexically self-satisfied. it puts us in touch with pure reason, not the practical reason of duties of care.[ ] if designers then manage to style a beauty that has an appeal beyond sociologically differentiated fields of taste,[ ] they will still find that their designs are not motivating active sustainment; being beautiful means being cast as the self-sufficient object of a distanced pleasantness. instructive of this is the recent western appropriation of wabi sabi, where beauty is found in imperfect and changing products and environments, but precisely by sitting back and watching disrepair take place.[ ] within this platonic-kantian legacy, designing the sort of beauty that will motivate humans to develop rituals of care for century-long product service lives is impossible; beauty points away from, not toward, the changing materiality of things. importantly though, the paraphrased protocol of responses to the hundred year cup brief implicitly attempted to negotiate this legacy by specifying a very particular type of beauty: not merely a pleasing form, but pleasurable function; beauty-in-use. i want to underline the extent to which such a notion is missed by platonic- kantian aesthetics qua what can appear and can be sensed - and i want to conclude by suggesting that it is for this very reason that such an escaped beauty just might be motivating of sustainment. post-heideggerian design theory suggests that good design withdraws. the sign of successfully satisfying human needs through appropriate design is the disappearance of the designed into ready-to- handedness.[ ] things that are beautiful to use are no longer things in the reified way that uselessly beautiful things are. in doing what they are designed to do, the useful, by definition, become incorporated into the background of whatever actions they are enabling.[ ] only when they breakdown do such well-designed things return to our senses as objects.[ ] only then could a kantian appreciate their platonic beauty. beautiful use is therefore non-sensical: it doesn't make sense within the platonic-kantianism that structures modern thought; and it is not something that is able to be sensed, according to the ontological account of what it means to use well-designed things. in short, is it possible to design a beautifully fragile, yet eminently desirable to use, cup? would not the former force the cup behind locked glass doors? or would not the latter lead to such a transparent tea drinking experience that one would forget to place the cup back in the cupboard, and instead expose it to the next careless gesture? if there is a beauty-in-use, it must be other than the appreciation of pure aesthetic beauty, and it must be the sort of appreciation that does not coincide with use, but perhaps comes afterwards.[ ] the pleasure of beautiful use must be the sort of devolved pleasure that comes from a sense of accomplishment. it is not a platonic-kantian appreciation of beauty, but nonetheless still an appreciation. rather than being pleasing, it is a thankfulness. one thinks of the designer, invariably anonymous, who made possible this cup of tea, and thanks him or her that there is this thing, where there could be have been nothing. it is because this unmetaphysical judgement of beauty-in-use takes the form of giving thanks, that it is active, returning the favour by taking the form of care.[ ] its retroactivity is what allows it move it from contemplation to preservation and extension. the fable then of the exercise of the tea cup is that beauty alone is no longer motivating of care. we are no longer romantic and love beauty with a soft excessiveness that is cluttering our world with junk. for the designer to design rituals of care, a different sense of the beautiful needs to be designed into the experience of designed products and environments. things need to be designed that will and can be thanked; design them well, to do appropriately what needs to be done; and then afford ways in which lay users can say thanks, lending a hand to maintaining the designed. this is the virtuous circle of the usefully beautiful and thankfully maintained, one that should be centripetal against the platonic-kantian forces that are concealing piles of wasted short-life 'durable' goods beneath the changing appearances of the beautiful. cameron tonkinwise is co-ordinator of design studies, university of technology sydney and executive officer, ecodesign foundation. [ ] this is how chris turner translates philippe lacoue-labarthe's preferred translation in heidegger, art and politics oxford: basil blackwell, . [ ] in particular, the study they co-authored, the literary absolute: the theory of literature in german romanticism albany: state university of new york, . [ ] klein's comprehensive etymological dictionary of the english language amsterdam: elsevier, [ ] this is lacoue-labarthe's thesis in heidegger art and politics. [ ] nancy discusses his notion of eco-technics in 'war, right, sovereignty- techne' in being singular plural stanford: stanford university press, and also in the sense of the world minneapolis: university of minnesota press, . i am also following nancy's 'the vestige of art' in the muses stanford: stanford university press, . [ ] see 'design and the environment' in for a critique of the political economy of the sign st louis: telos press, . [ ] for an examination of this, see max oelschlaeger the idea of wilderness new haven: yale university press, . [ ] for just one amongst many examples see the rather simplistic work of sim van der ryn and stuart cowan ecological design washington d.c.: island press, . the metaphors in this sentence from p. hawken, a. lovins and h. lovins' natural capitalism london: earthscan, are pure schiller: 'we may never grow as skilful as spiders, abalone, diatoms or trees, but smart designers are apprenticing themselves to nature to learn the benign chemistry of its processes.' ( ) [ ] these terms 'constrain, map and afford' are donald norman's terms from the design of everyday things london: mit press, ( ). [ ] jaap jelsma has been bringing the work of bruno latour on 'technology as delegated morality', and madeleine akrich's notion of 'technological user scripts' to the design of more sustainable ways of living in a number of recent papers: see for example, 'design of behaviour steering technology', a briefing paper for the international summer academy on technology studies, available at www.ifz.tu-graz.ac.at/sumacad/saoo.jelsma.pdf (last accessed march , ). [ ] it was aristotle who, contra plato, made clear that the prescriptiveness of tecnne was inappropriate for the relational finitude of human being. this does not mean however that 'you can never change human nature' or that it is impossible to predict how users will respond - humans are constitutionally open to being persuaded. it does mean however that such a 'design as rhetoric' is in no way a technique, like behaviourism - it is a never completely masterable skill of attunement. on what a non-techneu-based designing involves see joseph dunne back to the rough ground: practical judgement and the lure of technique notre dame: university of notre dame, and bent flyvbjerg making social science matter: why social inquiry fails and how it can succeed again cambridge: cambridge university press, . [ ] in 'the voice of sustainment' in the first edition of design philosophy papers, tony fry reiterated what he has called for some time the danger of 'sustaining the unsustainable'. it worth emphasising that this phrase refers to both, poorly targeted ecodesign, reducing the ecological impact of fundamentally unsustainable lifestyles - for example, making more energy efficient clothes dryers for climates where air drying is always possible, if 'users' can just learn to wait to do washing on sunny days, or have well-designed passive solar architecture - but also piece-meal ecodesign, making possible and sometimes promoting lifestyle rebound effects - for example, more energy- and water- efficient clothes washers (combined with diligent air drying) encouraging 'users' to wash more often than is perhaps necessary, because it is cheap and apparently 'less harmful' (per wash, but then not overall). this second could perhaps be called 'unsustaining the sustainable'. [ ] well-travelled students point out that in india cups are made from mud- based ceramics that can be smashed after use into a pile that is later re-turned into cups. manzini has for some time proposed the need to differentiate i) short- life products that are biodegradable, ii) mid-life products that are repairable and remanufacturable, iii) eternal products: cf michael braungart's intelligent product system - http://www.epea.com/englishlips.html(accessed may , ). http://www.ifz.tu-graz.ac.at/sumacad/saoo.jelsma.pdf [ ] people are asked to nominate products that need to be single-use disposable. of those nominated, 'alternative function fulfilment' almost always exists in the past or other cultures: the hand replacing toilet paper, the reuseable 'rubber' condom, the washable sanitary pad and nappy. [ ] many of tony fry's philosophical groundings of 'design-craft-care' are collected in remakings: ecology, design, philosophy sydney: envirobooks, . [ ] see manzini's 'scenarios of sustainable wellbeing' design philosophy papers no. , . [ ] this phrase comes from manzini's 'prometheus of the everyday: the ecology of the artificial and the designer's responsibility' in richard buchanan & victor margolin eds discovering design: explorations in design studies chicago: university of chicago press, . [ ] see ed van hinte edeternally yours rotterdam: publishers, and www.eternally-yours.org. [ ] abraham moles 'the comprehensive guarantee: a new consumer value' design issues vol. no. ( ). [ ] see chapter 'the process of repair' in christopher alexanderthe timeless way of building new york: oxford university press, . [ ] for collections of reports on designing sustainable service systems, see www.suspronet.org and www.pss-info.com. [ ] see manzini's warnings about these lifestyle rebound effects in 'scenarios of sustainable wellbeing' design philosophy papers no. . [ ] in this context, eternally yours go a step further in the century tea cup design, initiating 'user care relationships' by getting users to participate in the making of their own cups, or, at the least, in remaking the cups in some way, http://www.eternally-yours.org. http://www.suspronet.org http://www.pss-info.com. such as personalising them. see ed van hinte ed eternally yours rotterdam: publishers, . [ ] this dangerously reductive account is based on martin heidegger's interpretations of poiesis in plato and aristotle. see for example 'on the essence and concept of phiisis', translated by thomas sheehan in mcneill, w. ed pathmarks cambridge: cambridge university press, - , - , and s b 'the capability of producing: logos as innermost framework' of brogan, w & peter warnek trans. aristotle's metaphysics ix, - : on the essence and actuality of force bloomington: indiana university press, . [ ] this worldview is unworldly because in a platonic-christian way, things of this world are considered less 'real' than their appearance whose truth lies in some otherworldly eternal realm. [ ] this is hannah arendt's diagnosis of the problem 'the west' has inherited from the romanticisation of plato's aesthetics, one which leads directly to a 'waste economy': see s 'a consumers' society', the human condition, pp. - and the whole final part 'the vita activa and the modern age'. [ ] 'explication of the beautiful inferred from the third moment: beauty is an object's form of purposiveness insofar as it is perceived in the object without the presentation of a purpose.' immanuel kant critique of judgement trans.werner pluhar indiana: hackett, , . [ ] kant expressly differentiates the judgement of beauty from that of 'perfection' because the latter assumes 'adequation' either to what something is (quantitative) or what it is for (qualitative). beauty is a perfect instance of one knows not what. this is precisely why judgements of beauty offer short-cuts to a completion that reason can only approach developmentally and so always inadequately: see s 'a judgement of taste is wholly independent of the concept of perfection', . [ ] see s - of the critique of judgement where kant insists that the artistically beautiful is the work of genius, meaning both having-been made by an expert maker (nature's spirit working through man), and, unable to be developed any further, like science, or imitated. [ ] kant concludes part one of the critique of judgement by arguing that 'beauty is a symbol of morality' (s , - ). his point however is that beauty presents to humans the conjoining of freedom and lawfulness; that is, it presents that harmony as something intelligible, not as something motivating. the latter is exactly what the jena romantics felt the need to undertake to supplement the abstract purity of kant's critiques. [ ] this is pierre bourdieu's critique of kant's third critique in distinction cambridge: harvard university press, [ ] see leonard koren wabi sabi: for artists, designers, poets and philosophers stone bridge press, . [ ] one of the clearest applications of heidegger's ready-to-hand to design is set out in fernando flores and terry winograd's understanding computers and cognition reading: addison-wesley, . [ ] for a beautiful description of this, see fatma korkut's contribution to wolfgang jonas' basic paradox forum: http://home.snafu.de/jonasw/paradoxkorkute.html(accessed may , ). [ ] for an extended analysis of the ontological difference between the ready-to- hand and the broken-down, with radical consequences for the interpretation of heidegger's philosophy, see graham harman's tool-being: heidegger and the metaphysics of objects chicago: open court, . [ ] what i am trying to get at here is what i think peter-paul verbeek and petran kockelkoren are trying to get at in 'the things that matter' design issues vol. no. (autumn ). my small essay is part of an ongoing attempt to flesh out what verbeek and kockelkoren point to in this important article. after criticising alienating platonism in the same way that i have here, for the way it misses the thingliness of things, and thus necessity to take care of things, verbeek and kockelkoren propose as a response the ambiguous idea of 'transparent yet engaging objects'. [ ] i am here trying to make a way of translating some heideggerian motifs into design for sustainability: his use of periander's command, 'take into care beings as a whole' in his lecture, basic concepts bloomington: indiana university press, ; his linking via english etymology of thinking to thanking at the start page page page page page page page page page page page page approach of the value of a rent when non-central moments of the capitalization factor are known: an r application with interest rates following normal and beta distributions science & philosophy issn: - vol. ( ), , pp. -- eissn: - is the golden section a key for understanding beauty? part ii (la sezione aurea è una chiave per la comprensione del bello?) parte ii franco eugeni and luca nicotra received: - - . accepted: - - . published: - - doi: . /sp.v i . ®eugeni and nicotra abstract our goal is to prove that the golden section, however important, is not the only key to understand a mathematical-formalizing approach to the idea of beauty. having developed, from this point of view, reading keys linked to the post- modern, it is necessary to link together the multiple rivulets of knowledge that gather in this direction. moreover the canons of the approaches presented up to now are very indicative for the understanding of many aspects of beauty,  teramo university. full professor of logics and science philosophy, teramo, italy; eugenif @gmail.com.  cultural association “arte e scienza”, president. mechanical engineer and editor in charge of the artescienza magazine, rome, italy; luca.nicotra @gmail.com. mailto:eugenif @gmail.com mailto:luca.nicotra @gmail.com franco eugeni and luca nicotra which however depends on the historical moment and the cultures created in the various civilizations. therefore we can affirm that there is no effective definition of "beauty" that can be codified through fixed canons, but that the concept is expressed by a series of stratifications and interpretations that tend to link several major variations, expressing the various answers given by man to the question: what is the beauty? keywords: golden section, golden number, beauty, golden rectangle, fractals sunto nostro obiettivo è provare che la sezione aurea, per quanto di importanza notevole, non è l’unica chiave per comprendere un approccio matematico- formalizzante dell’idea di bellezza. essendosi sviluppate, da questo punto di vista, chiavi di lettura legate al post-moderno, occorre legare tra loro i molteplici rivoli di saperi che si addensano in questa direzione. inoltre i canoni degli approcci fino ad oggi presentati sono molto indicativi per la comprensione di numerosi aspetti della bellezza, che però dipende dal momento storico e dalle culture createsi nelle varie civiltà. pertanto possiamo affermare che non esiste una effettiva definizione del "bello" che possa essere codificata attraverso canoni fissi, ma che il concetto si esprime con una serie di stratificazioni e interpretazioni che tendono a collegare fra loro numerose varianti principali, esprimenti a loro volta le varie risposte date dall’uomo alla domanda: cosa è il bello? parole chiave: sezione aurea, numero aureo, bellezza, rettangolo aureo, frattali una disamina del numero aureo ciò che definisce la sezione aurea è la proporzione secondo la quale un segmento è diviso in due parti disuguali. per numero aureo, dunque, si dovrebbe intendere un numero che caratterizza tale proporzione. l’assegnazione dell’aureola di “aureo” all’uno o all’altro dei due numeri Φ = , e φ = , è quindi arbitraria, in quanto entrambi caratterizzano la sezione aurea di un segmento. normalmente si chiama numero aureo Φ e numero aureo coniugato φ. anche il legame con la successione di fibonacci è mantenuto sia da Φ sia da φ. infatti Φ è il limite, al tendere all’infinito, dei rapporti fra un termine e il is the golden section a key for understanding beauty? part ii precedente della successione di fibonacci, mentre φ è il limite, al tendere all’infinito, dei rapporti fra un termine e il successivo della stessa successione. tuttavia ci sono altri due numeri che caratterizzano la proporzione della sezione aurea, ma sono normalmente ignorati. i quattro numeri “aurei” che caratterizzano la sezione aurea emergono dai possibili modi in cui algebricamente si può impostare la relazione che intercorre fra i suoi tre elementi: l’intero segmento e le sue parti maggiore e minore. la soluzione algebrica della divisione di un segmento in media ed estrema ragione si trova facilmente assumendo come incognita x la misura di uno dei tre segmenti coinvolti e scegliendo come unità di misura uno dei due rimanenti. i casi possibili sono dunque le disposizioni di classe (il primo elemento è uno dei tre segmenti della sezione aurea assunto come unità di misura e il secondo elemento è un altro dei rimanenti due segmenti assunto come incognita) di oggetti (i tre segmenti della sezione aurea) e sono pertanto sei. ° caso l’unità di misura è l’intero segmento e l’incognita il segmento di media ragione: : x = x: ( - x), da cui x = ( - x) e infine: x + x - = . le due radici di questa equazione di ° grado, sono: luca nicotra, osservazioni critiche sulla sezione aurea. “convegno “matematica, natura, architettura”, novembre , mathesis- dipartimento di architettura, napoli. si potrebbe scegliere anche una unità di misura diversa dai tre segmenti della sezione aurea, ma sceglierla all’interno di tale terna permette di avere come radici dell’equazione algebrica direttamente i rapporti fra i tre segmenti stessi. dato un insieme di n oggetti distinti e q < n le disposizioni semplici degli n oggetti presi a gruppi di q sono tutti i possibili raggruppamenti di q oggetti scelti fra gli n in modo tale che ciscun gruppo contenga q degli n oggetti e che due gruppi siano distinti per almeno un oggetto o per l’ordine degli oggetti contenuti. il numero di disposizioni di classe q di n oggetti è d n,q = n! / (n – q)! = (n- ) x--- x (n-q+ ), ovvero il prodotto di q numeri naturali decrescenti a partire da n. x e x sono irrazionali e quindi risultano costituiti da un numero infinito di cifre decimali prive di periodicità. normalmente si considerano tre cifre decimali. franco eugeni and luca nicotra x = − −√ = - , … ; x = − +√ = , … la radice negativa corrisponde a un punto esterno all’intero segmento che lo divide esternamente secondo la proporzione aurea. essa per tale motivo non viene presa in considerazione. dunque è x = − +√ = , . ° caso l’unità di misura è il segmento di media ragione e l’incognita è l’intero segmento: x : = : (x - ), da cui x (x- ) = e infine: x - x - = . le due radici di questa equazione di ° grado, sono: x = −√ = - , … ; x = +√ = , … la prima, come nel caso precedente, non ha significato geometrico e per tale motivo non viene presa in considerazione. dunque è x = +√ = , . ° caso l’unità di misura è l’intero segmento e l’incognita il segmento di estrema ragione: : ( - x) = ( - x) : x da cui ( - x ) = x e infine: x - x + = . le due radici di questa equazione di ° grado, sono: is the golden section a key for understanding beauty? part ii x = −√ = , ; x = +√ = , . la seconda ovviamente non ha significato geometrico. dunque è x = −√ = , . ° caso l’unità di misura è il segmento di estrema ragione e l’incognita l’intero segmento: x : (x – ) = (x – ): , da cui (x – ) = x e infine: x - x + = , come nel ° caso, ma ora delle due radici reali e distinte quella accettabile è x = +√ = , . ° caso l’unità di misura è il segmento di media ragione e l’incognita il segmento di estrema ragione: ( + x ) : = : x, da cui x ( + x) = , e infine: x + x - = , come nel ° caso. delle due radici reali e distinte quella accettabile è x = − +√ = , . ° caso l’unità di misura è il segmento di estrema ragione e l’incognita il segmento di media ragione: franco eugeni and luca nicotra (x + ) : x = x : , da cui (x + ) = x , e infine: x - x - = , come nel ° caso. delle due radici reali e distinte quella accettabile è x = +√ = , . in conclusione, tutte le possibili impostazioni algebriche della divisione di un segmento in media ed estrema ragione mostrano l’esistenza di quattro distinti rapporti che possono caratterizzarla: • rapporto fra l’intero segmento e la parte maggiore Φ = 𝐴𝐵 𝐴𝑆 = +√ = , ; • l’inverso del precedente rapporto φ = 𝐴𝑆 𝐴𝐵 = − +√ = , ; • rapporto fra l’intero segmento e la parte minore Φ = 𝐴𝐵 𝑆𝐵 = +√ = , ; • l’inverso del precedente rapporto φ = 𝑆𝐵 𝐴𝐵 = −√ = , . fra di essi intercorrono le seguenti relazioni: Φ = +√ = − +√ = + − +√ = + 𝜑 φ = − +√ = Φ Φ = +√ = + +√ = + Φ = + 𝜑 φ = −√ = Φ . proprietà del numero aureo Φ = , il numero Φ = , …, in quanto radice dell’equazione x - x - = (vedi ° e ° caso del parag. ), soddisfa la relazione: Φ - Φ - = , da cui: ( ) Φ = Φ + = Φ dalla quale moltiplicando ripetutamente entrambi i membri per Φ si ottiene: Φ = Φ + Φ Φ = Φ + Φ ( )’ Φ = Φ + Φ Φ = Φ + Φ ………………………… is the golden section a key for understanding beauty? part ii Φ n = Φn- + Φn- . la ( ) mostra che il quadrato del numero aureo Φ contiene la stessa parte decimale di Φ stesso: Φ = , …. inoltre le ( ), ( )’ mostrano che la potenza n_esima di Φ è uguale alla somma delle due potenze precedenti di Φ stesso. dalla ( ) dividendo entrambi i membri per Φ si ha: Φ = + / Φ = + φ. i due numeri aurei Φ e φ differiscono per l’unità. le ( ) , ( )’ si possono scrivere anche per sostituzioni successive: Φ = Φ + Φ = Φ + Φ = Φ + + Φ = Φ + Φ = Φ + Φ = Φ + + Φ + = Φ + ( )’’ Φ = Φ + Φ = Φ + + Φ + = Φ + Φ = Φ + Φ = Φ + + Φ + = Φ + …………………… Φ n = fn Φ + fn- essendo fn l’ennesimo numero della successione di fibonacci: , , , , , , , , , , , … le ( )’’ forniscono un modo diretto per calcolare le successive potenze intere del numero aureo Φ tramite i numeri di fibonacci: la potenza n_esima di Φ si può ottenere moltiplicando Φ per l’ennesimo numero della successione di fibonacci e addizionandovi il numero precedente. . proprietà del numero aureo φ = , il numero φ = , …, in quanto radice dell’equazione x + x - = (vedi ° e ° caso), soddisfa la relazione: φ + φ – = , da cui: ( ) φ = - φ = φ dalla quale moltiplicando ripetutamente entrambi i membri per φ si ottiene: φ = φ - φ φ = φ - φ ( )’ φ = φ - φ luca nicotra, osservazioni critiche sulla sezione aurea, op. cit. franco eugeni and luca nicotra φ = φ - φ …………………... φ n = φ n- - φ n- . le ( ), ( )’ mostrano che la potenza n_esima di φ è uguale alla differenza fra le due potenze precedenti di φ stesso cambiata di segno. le ( ), ( )’ si possono scrivere anche per sostituzioni successive: φ = - φ φ = φ - φ = φ - + φ = φ - φ = φ - φ = - φ - φ + = - φ + ( )’’ φ = φ - φ = φ - + φ - = φ - φ = φ - φ = - φ + - φ + = - φ + …………………………………………………………………….. φn = (- ) n- fn φ + (- ) n fn- . la potenza n_esima di φ si può ottenere moltiplicando φ per l’ennesimo numero della successione di fibonacci preso col segno negativo se n è pari e col segno positivo se n è dispari e addizionandovi il numero precedente se n è pari, sottraendolo se n è dispari. . proprietà dei numeri aurei Φ = , e φ = , poiché Φ = , e φ = , sono radici della stessa equazione, per essi valgono le stesse proprietà da questa ricavabili. infatti entrambi soddisfano l’equazione x - x + = (vedi ° e ° caso del parag. ) e quindi si può scrivere per Φ (lo stesso per φ ): ( ) Φ = Φ - dalla quale moltiplicando ripetutamente entrambi i membri per Φ si ottiene: Φ = Φ - Φ Φ = Φ - Φ Φ = Φ - Φ Φ = Φ - Φ ( )’ …………………. Φ n = Φ n- - Φ n- . luca nicotra, osservazioni critiche sulla sezione aurea, op. cit. is the golden section a key for understanding beauty? part ii le ( ), ( )’ si possono scrivere anche per sostituzioni successive: Φ = Φ – Φ = ( Φ - ) - Φ = Φ - ( )’’ Φ = ( Φ - ) - ( Φ - ) = Φ – Φ = ( Φ - ) - ( Φ – ) = Φ – Φ = ( Φ - ) - ( Φ - ) = Φ - osservando la successione di fibonacci, si conclude facilmente che nelle ( )’’ Φ viene moltiplicato per il numero di fibonacci che occupa il posto doppio del grado n della potenza di Φ considerata e gli viene sottratto il numero di fibonacci che precede quel numero di due posti: n= n= n= n= n= grado , , , , , , , , , , , ,…… ° ° ° ° ° posto pertanto possiamo scrivere così il termine generale delle ( )’’: Φ n = f n Φ – f n- . . i numeri  e  come radici e frazioni continue la sezione aurea gode di interessanti espressioni numeriche infinite. infatti  e  si possono rappresentare come radice continua o come frazione continua in modo singolare: l’unica cifra presente è . consideriamo l’estrazione di radice continua: 𝑅 = √ + √ + √ + … … …. il suo quadrato è: r = + √ + √ + √ + … … … = + r, da cui si ottiene l’equazione: luca nicotra, osservazioni critiche sulla sezione aurea, op. cit.. franco eugeni and luca nicotra r - r - = ovvero la stessa equazione del ° caso del paragrafo , ove l’incognita è indicata con r anziché con x e la cui radice positiva sappiamo già essere il numero aureo Φ. pertanto possiamo scrivere: Φ = 𝑅 = √ + √ + √ + … aggiungendo successivamente radici di , si ottengono valori sempre più approssimati del numero aureo Φ: , . , . , . , . , . , . , …. analogamente possiamo considerare la frazione continua: 𝐹 = + + + + + ⋯ che si può scrivere: 𝐹 = + + + + + ⋯ = + 𝐹 da cui si ottiene l’equazione: f – f – = ovvero ancora una volta la stessa equazione del ° caso del paragrafo , ove l’incognita è ora indicata con f anziché con x e la cui radice positiva sappiamo già essere il numero aureo Φ. pertanto possiamo scrivere: Φ = 𝐹 = + + + + + ⋯ is the golden section a key for understanding beauty? part ii cioè abbiamo ottenuto un’altra espressione che permette di calcolare i successivi valori approssimati di Φ. consideriamo ora la frazione continua: 𝐹 = + + + + ⋯ che si può scrivere: 𝐹 = + + + + ⋯ = + 𝐹 da cui si ottiene l’equazione: f + f – = ovvero la stessa equazione del ° caso del paragrafo , ove l’incognita è indicata ora con f anziché con x e la cui radice positiva sappiamo già essere il il numero aureo φ. pertanto possiamo scrivere: φ = + + + + ⋯ espressione che permette di calcolare i successivi valori approssimati di φ. costruzioni geometriche della sezione aurea le costruzioni geometriche della sezione aurea, dirette e inverse, possono essere realizzate con la geometria sintetica o con la geometria analitica. franco eugeni and luca nicotra il problema diretto della costruzione della sezione aurea è quello in cui è dato un segmento e si vuole individuare il punto al suo interno che lo divide in media ed estrema ragione; il problema inverso del precedente consiste nel costruire il segmento che ammette come parte maggiore o come parte minore della sua sezione aurea un dato segmento. le costruzioni geometriche sintetiche della sezione aurea fanno ricorso unicamente a proprietà della geometria sintetica e sono piuttosto laboriose. le costruzioni geometriche analitiche, invece, si basano su interpretazioni geometriche delle soluzioni delle equazioni algebriche che definiscono la sezione aurea nei vari casi indicati al. paragrafo ; esse sono generalmente molto più agili e rapide di quelle sintetiche. . costruzione geometrica sintetica della sezione aurea nell’ambito della geometria sintetica, la prima costruzione diretta della sezione aurea di un segmento di cui si abbia notizia è quella proposta da euclide nella proposizione del libro ii degli elementi. espressa in termini semplificati, la costruzione si svolge con riga e compasso secondo quanto da figura – costruzione geometrica sintetica diretta della sezione aurea del segmento ab secondo euclide (elementi, libro ii, prop. ). fig. a: la costruzione con riga e compasso in termini moderni. fig. b: la costruzione originale di euclide basata su proposizioni precedenti degli elementi. la costruzione è avvalorata dall’equivalenza fra il quadrato ahgf e il rettangolo hbdk. is the golden section a key for understanding beauty? part ii noi indicato in figura a. nella figura b, invece, è riportata la costruzione originale di euclide che non fa uso di riga e compasso, ricorrendo soltanto a proposizioni da lui precedentemente dimostrate (le denominazioni dei punti sono quelle originali di euclide). sia ab il segmento sul quale costruire la sezione aurea. costruito su ab il quadrato abcd, facendo successivamente centro in a e in c si traccino due archi di circonferenza di raggio ab e dal loro punto di intersezione si tracci la perpendicolare a ca che interseca ca nel suo punto medio e. quindi si congiunga questo con b. facendo centro in e si tracci un arco di circonferenza di raggio eb e sia f il suo punto di intersezione con la retta ca. ebbene, l’arco di circonferenza con centro in a e raggio af interseca in h il segmento ab dividendolo in media ed estrema ragione, essendo: ab : ah = ah : hb, poiché il rettangolo che ha per lati ab, hb è equivalente al quadrato di lato ah: ab x hb = ah . la dimostrazione fornita da euclide (figura b) consiste proprio nel dimostrare l’equivalenza fra il quadrato ahgf costruito su ah e il rettangolo hbdk avente per lati hb e bd = ab; essa è piuttosto macchinosa e si basa soltanto su precedenti proposizioni degli elementi. la possiamo seguire nella traduzione moderna di fabio acerbi: sia data la retta ab: si deve pertanto secare ab cosicché il rettangolo compreso da quella totale e dall'uno o dall'altro dei segmenti ugule al quadrato sul restante segmento. si descriva su ab il quadrato abdc (prop. - ), e si sechi ac a metà nel punto e (prop. - ) e si congiunga b con e; e si prolunghi ca nell’ordine richiamato sono le seguenti: libro i - prop. : descrivere sulla retta data un quadrato libro i - prop. : secare a metà la retta limitata data libro i - prop. : di due rette disuguali date, sottrarre dalla maggiore una retta uguale alla minore. libro ii – prop. : qualora una linea retta sia divisa a metà, e una certa retta sia sommata ad essa in linea retta, il rettangolo compreso da quella totale insieme con quella sommata e da quella sommata più il quadrato sulla metà è uguale al quadrato su quella composta sia dalla metà sia da quella sommata). libro i - prop. : nei triangoli rettangoli il quadrato sul lato che sottende l'angolo retto è uguale ai quadrati sui lati che comprendono l'angolo retto. http://www.scienzaatscuola.it/euclide/home/libro /prop - .html. franco eugeni and luca nicotra fino a f (prop. - ), e si ponga be uguale a ef; si descriva su af il quadrato fh e si conduca gh fino a k (prop. - ): dico che ab risulta secata secondo h in modo da formare il rettangolo ab pr bh uguale al quadrato su ah. poiché infatti la retta ac risulta secata a metà in e, e ad essa risulta sommata fa, il rettangolo cf per fa più il quadrato su ae è uguale al quadrato su ef (prop. - ). ma ef è uguale a eb, il rettangolo cf per fa insieme al quadrato su ae è uguale al quadrato su eb poiché infatti la retta ac risulta secata a metà in e, e ad essa risulta sommata fa, il rettangolo cf per fa più il quadrato su ae è uguale al quadrato su ef (prop. - ). ma ef è uguale a eb, il rettangolo cf per fa insieme al quadrato su ae è uguale al quadrato su eb. ma la somma dei quadrati su ba e ae è uguale al quadrato su eb (prop. - ), l'angolo su a è infatti retto, il rettangolo cf per fa insieme al quadrato su ae è uguale è uguale alla somma dei quadrati su ba e ae. si sottragga quello su ae comune; il rettangolo restante cf per fa è uguale quindi al quadrato su ab. il rettangolo fa per fk è fk, af è infatti uguale a fg, e il quadrato su ab è ad, fk è quindi uguale a ad. si sottragga ak comune: fh restante è allora uguale a hd. e hd è il rettangolo ab per bh, ab è infatti uguale a bd, e fh è il quadrato su ah; il rettangolo ab per bh è quindi uguale a quadrato su ah. figura - elementi di euclide, tradotti in italiano da niccolò tartaglia ( ). edizione del . is the golden section a key for understanding beauty? part ii la retta data ab risulta quindi secata secondo h così da fare il rettangolo ab per bh uguale al quadrato su ah. a titolo informativo riportiamo la versione della stessa costruzione tratta dagli elementi di euclide tradotti in italiano da niccolò tartaglia nel : problema . . propositione . . [ / ] puotemo segare una data linea retta si conditionatamente che il rettangolo che è contenuto sotto di tutta la linea, & di una parte, sia equale al quadrato che uien fatto dell’altra parte. figura r. sia data la linea ,a,b, la qual uolemo diuidere cosi conditionatamente che quel che uien produtto da tutta la linea in la sua menor parte sia equale al quadrato dell’altra maggior parte, & per far tal cosa descriuerò il quadrato sopra la detta linea .a.b. (per la quadragesima sesta del primo) il qual, sia ,a,b,c,d, & diuido il lato ,b,d, in due parti equale in ponto ,e, et produco la ,a,e, & slongo etiam la ,e,b, fina in ponto ,f, talmente che la ,e,f, sia equale alla ,a,e, et sopra la parte istrinsica ,b,f, descriuo (per la quadragesima sesta del primo) il quadrato ,b,f,g,h, il quale sega dalla linea ,a,b, la parte ,b,h, equale alla parte ,b,f, hor dico che la linea ,a,b, è diuisa talmente in ponto ,h, che quello che è fatto da tutta la linea ,a,b, in la sua minor parte ,a,h, è equale al quadrato dalla parte ,b,h. et per dimostrar questo slongo la ,g,h, per fin al k laqual serà equidistante al ,a,c. perche adonque la linea ,d,b, è diuisa in due parti equale in ponto ,e, & a quella gliè aggiunta la linea ,b,f. il rettangolo compreso sotto a tutta la linea ,d,f, & alla linea ,b,f, col quadrato della e.b. per la sesta di questo, serà equale al quadrato della ,e,f, & perche .e.f. si è equale alla .e.a. il rettangolo adonque fatto della ,d,f, in la ,b,f, con lo quadrato della ,e,b, serà equale al quadrato della .e.a. & perche il quadrato della ,e.a. (per la penultima del primo) si è equale alli duoi quadrati delle due linee .e.b. & .a.b. seguita adunque che’l rettangolo della .d.f. in la .b.f. con lo quadrato della .e.b. sia equale al medesimo quadrato della .e.b. insieme con lo quadrato della ,a,b, leuando uia da l’una & l’altra summa il quadrato della ditta .e.b. li duoi rimanenti (per la tertia concettione) seranno fra loro equali, delli quali rimanenti l’uno serà il rettangolo fatto della d.f. nella .b.f. & l’altro è il quadrato della .a.b. & perche il È la prima versione degli elementi di euclide pubblicata in italiano e anche la prima edizione in una lingua europea moderna, basata sia sulla traduzione latina dall’arabo di campano da novara del (che è la prima edizione stampata degli elementi), sia sulla traduzione latina dal greco di bartolomeo zamberti del . franco eugeni and luca nicotra rettangolo fatto della d.f. nella .b.f. si è la superficie ,d,g, perche .f.g. è equale al .b.f. (per esser ciascun di loro lato del quadrato .b.f.g.h.) adonque la superficie .d.g. serà equale al quadrato della .a.b. cioè al quadrato .a.d. hor se communamente ne cauamo la superficie .d.h. li duoi rimanenti seranno anchora equali (per la detta tertia concettione) l’uno di quali rimanenti è la superficie .a.k. l’altro serà il quadrato .b.f.g.h. & perche la superficie .a.k. è contenuta sotto a tutta la linea .a.b. & alla sua minor parte .a.h. (per essere .a.c. equale à .a.b.) & lo quadrato .b.f.h.g. è il [pag. v] quadrato de ,b,h, cioe de l’altra sua maggior parte, adonque la linea ,a,b, serà diuisa secondo il proposito nel ponto ,h, perche la superficie, ouer rettangolo de tutta la linea ,a,b, in la sua minor parte .a.h. è equale al quadrato dell'altra sua maggior parte ,h,b, et nota che non bisogna afaticarsi in uoler diuidere in questo modo un numero perche è impossibile, come in la uigesima nona del sesto si manifesterà. . costruzione geometrica analitica della sezione aurea . . costruzioni dirette le interpretazioni geometriche delle soluzioni delle equazioni dei casi , del paragrafo permettono altrettante costruzioni analitiche dirette della sezione aurea, in quanto in quei casi è dato il segmento ab (assunto come unità di misura) e le soluzioni delle equazioni forniscono le misure rispetto ad esso o della parte maggiore (caso ) o della parte minore (caso ) della sezione aurea di ab, permettendo quindi di individuare al suo interno il punto s che lo divide in media ed estrema ragione. costruzione geometrica diretta della sezione aurea: ° caso parag. riprendiamo l’equazione che definisce la sezione aurea di un segmento ab nel caso in cui si sceglie come incognita x la misura della parte maggiore e come unità di misura ab stesso: x + x - = . abbiamo già visto che delle due radici reali e distinte ha significato geometrico soltanto quella positiva: ( ) x = − +√ = , … per ottenere una costruzione geometrica diretta della sezione aurea basterà trovare una interpretazione geometrica della ( ). a tal fine possiamo scrivere ( )’ x = − +√ = − + √( ) + = , . is the golden section a key for understanding beauty? part ii orbene, l’interpretazione geometrica della ( )’ è immediata: il radicale è la misura dell’ipotenusa ca di un triangolo rettangolo i cui cateti ab e bc misurano e / . sottraendo da tale ipotenusa un segmento di misura / (ovvero un segmento congruente con il cateto bc) otterremo il segmento as’ congruente con la parte maggiore della sezione aurea di ab, poiché la sua misura rispetto ad ab è data dalla ( )’ ovvero è x = , ... la costruzione geometrica analitica diretta della sezione aurea del segmento ab è pertanto immediata (figura ): costruito il triangolo rettangolo abc tale che ab = e bc = , puntiamo il compasso in c e con raggio cb riportiamo il cateto bc su ca in cs’. pertanto, puntando il compasso in a con apertura pari ad as’, basta tracciare l’arco di circonferenza s’s per ottenere su ab il punto s che divide ab in media ed estrema ragione, ovvero secondo la sua sezione aurea. . . costruzioni inverse le interpretazioni geometriche delle soluzioni delle equazioni dei casi , del paragrafo permettono altrettante costruzioni analitiche inverse della questo caso è trattato in federigo enriques e ugo amaldi, elementi di geometria, parte seconda, bologna, zanichelli, , p. . figura – costruzione geometrica analitica diretta della sezione aurea: dato il segmento ab individuare il punto s al suo interno che lo divide in media ed estrema ragione. franco eugeni and luca nicotra sezione aurea, in quanto in quei casi sono date rispettivamente o la parte maggiore o quella minore della sezione aurea (assunte come unità di misura) e le soluzioni delle equazioni forniscono la misura dell’intero segmento (assunto come incognita). anche le interpretazioni geometriche delle soluzioni delle equazioni dei casi , del paragrafo permettono altrettante costruzioni analitiche inverse della sezione aurea, poiché anche in quei casi sono date rispettivamente o la parte maggiore o quella minore della sezione aurea (assunte come unità di misura), ma le soluzioni delle equazioni forniscono questa volta rispettivamente la misura della parte minore o di quella maggiore, cosicché dalla somma delle due parti si può ricostruire l’intero segmento. costruzione geometrica inversa della sezione aurea: ° caso parag. riprendiamo l’equazione che definisce la sezione aurea di un segmento ab nel caso , in cui si sceglie come incognita x il segmento ab stesso e come unità di misura la parte maggiore as della sua sezione aurea: x - x - = . delle due radici reali e distinte sappiamo già che ha significato geometrico soltanto quella positiva: ( ) x = +√ = , ... analogamente al caso precedente possiamo scrivere la ( ) nella forma: ( )’ x = +√ = + √( ) + = , . l’interpretazione geometrica della ( )’ è immediata: il radicale è la misura dell’ipotenusa ca di un triangolo rettangolo i cui cateti as e sc misurano e / . addizionando a tale ipotenusa un segmento di misura / (ovvero un segmento congruente con il cateto sc) otterremo il segmento ad congruente con l’intero segmento ab della sezione aurea, poiché la sua misura rispetto ad as è data dalla ( )’ ovvero è x = , ... la costruzione geometrica analitica inversa della sezione aurea del segmento ab è pertanto immediata (figura ): costruito il triangolo rettangolo asc tale che as = e sc = / , puntando il compasso in c riportiamo cs sul prolungamento di ac. infine, puntando il compasso in a, si tracci un arco di circonferenza di raggio ad fino a intersecare in b la retta as: il segmento ab è il segmento cercato. is the golden section a key for understanding beauty? part ii costruzione geometrica inversa della sezione aurea: ° caso parag. riprendiamo l’equazione che definisce la sezione aurea di un segmento ab nel caso , in cui si sceglie come incognita x il segmento ab stesso e come unità di misura la parte minore sb della sua sezione aurea: x - x + = . delle due radici reali e distinte sappiamo già che ha significato geometrico soltanto: ( ) x = +√ = , che possiamo riscrivere così: ( )’ x = +√ = + + √( ) + = , il radicale della ( )’ è la misura dell’ipotenusa sc di un triangolo rettangolo i cui cateti sb e bc misurano e / . addizionando a tale ipotenusa un segmento di misura / (ovvero un segmento congruente con il cateto bc) otterremo il segmento sd = + √( ) + che sommato al segmento sb = figura – costruzione geometrica analitica inversa della sezione aurea: dato il segmento as trovare il segmento ab che ammette as come parte maggiore della sua sezione aurea. franco eugeni and luca nicotra dà come risultato il segmento cercato ab poiché la misura di questo è data proprio dalla ( )’. la costruzione geometrica analitica inversa della sezione aurea del segmento ab è pertanto immediata (figura ): costruito il triangolo rettangolo sbc tale che sb = e bc = / , puntando il compasso in c riportiamo cb sul prolungamento di bc. infine, puntando il compasso in s, si tracci un arco di circonferenza di raggio sd fino a intersecare in a la retta bs: il segmento ab è il segmento cercato. costruzione geometrica inversa della sezione aurea: ° caso parag. riprendiamo l’equazione che definisce la sezione aurea di un segmento ab nel caso , in cui si sceglie come incognita x la parte minore sb e come unità di misura la parte maggiore as della sezione aurea di ab: x + x - = . delle due radici reali e distinte quella accettabile è: ( ) x = − +√ = , . figura – costruzione geometrica analitica inversa della sezione aurea: dato il segmento sb trovare il segmento ab che ammette sb come parte minore della sua sezione aurea. is the golden section a key for understanding beauty? part ii che possiamo riscrivere così: ( )’ x = − +√ = - + √( ) + = , il radicale della ( )’ è la misura dell’ipotenusa ac di un triangolo rettangolo i cui cateti as e sc misurano e / . sottraendo da tale ipotenusa un segmento di misura / (ovvero un segmento congruente con il cateto sc) otterremo il segmento sd = - + √( ) + congruente alla parte minore sb della sezione aurea essendo la sua misura dalla ( )’. il segmento cercato è dunque ab =as+sb. la costruzione geometrica analitica inversa della sezione aurea del segmento ab è pertanto la seguente (figura ): costruito il triangolo rettangolo abc tale che ab = e bc = / , puntando il compasso in c riportiamo il segmento ca in cd sulla retta c. quindi con centro in s si tracci figura – costruzione geometrica analitica inversa della sezione aurea: dato il segmento maggiore as trovare il segmento minore sb che addizionato ad as fornisce l’intero segmento ab della sezione aurea. franco eugeni and luca nicotra l’arco di circonferenza di raggio sd fino a intercettare in b il prolungamento di as dalla parte di s. il segmento ab è il segmento cercato che ha as come parte maggiore della sua sezione aurea. costruzione geometrica inversa della sezione aurea: ° caso parag. riprendiamo l’equazione che definisce la sezione aurea di un segmento ab nel caso , in cui si sceglie come incognita x la parte maggiore as e come unità di misura la parte minore sb della sezione aurea di ab: x - x - = . delle due radici reali e distinte quella accettabile è : ( ) x = +√ = , che possiamo riscrivere così: ( )’ x = +√ = - + √( ) + = , il radicale della ( )’ è la misura dell’ipotenusa ac di un triangolo rettangolo i cui cateti sb e bc misurano e / . addizionando a tale ipotenusa figura – costruzione geometrica analitica inversa della sezione aurea: dato il segmento minore sb trovare il segmento maggiore as che addizionato ad sb fornisce l’intero segmento ab della sezione aurea. is the golden section a key for understanding beauty? part ii un segmento di misura / (ovvero un segmento congruente con il cateto bc) otterremo il segmento sd = + √( ) + congruente alla parte maggiore as della sezione aurea, essendo la sua misura data dalla ( )’. il segmento cercato è dunque ab =as+sb. la costruzione geometrica analitica inversa della sezione aurea del segmento ab è pertanto la seguente (figura ): costruito il triangolo rettangolo sbc tale che sb = e bc = / , puntando il compasso in c riportiamo il segmento cb in cd sul prolungamento di sc. quindi con centro in s si tracci l’arco di circonferenza di raggio sd fino a intercettare in a il prolungamento di sb dalla parte di s. il segmento ab è il segmento cercato che ha sb come parte minore della sua sezione aurea. un’altra costruzione geometrica analitica inversa della sezione aurea è quella stessa già indicata precedentemente nella parte i di questo articolo per la costruzione del rettangolo aureo. con riferimento, quindi, alla stessa figura allora utilizzata, assunto il segmento ab = e indicato con m il suo punto medio, risulta: mc = mb + bc = ( ) + = e quindi: me = mc = √ , ae = am + me = + √ = +√ = + √( ) + . dunque ae è il segmento cercato che ammette ab come parte maggiore della sua sezione aurea essendo il suo rapporto ad ab dato dalla ( )’ ovvero x = , . di conseguenza beè la parte minore della sezione aurea di ae. figura – la costruzione geometrica del rettangolo aureo interpretata come costruzione inversa della sezione aurea. franco eugeni and luca nicotra . costruzioni tecnologiche della sezione aurea la costruzione geometrica della sezione aurea di un segmento può essere realizzata molto rapidamente anche per mezzo di opportuni strumenti. un esempio è fornito dal compasso di goeringer. nel il pittore tedesco adalbert goeringer ideò un compasso a tre punte con la proprietà che quando le due punte estreme sono agli estremi di un segmento, la terza punta individua la sezione aurea di questo (figura ). il principio su cui si fonda il compasso di goeringer è molto semplice: l’utilizzo di aste le cui lunghezze sono numeri di fibonacci consecutivi e la similitudine dei triangoli da esse formate. in una possibile realizzazione si ha: af=ah= cm, bf=bg=ch= cm, ab=be=ec=ca = cm. dalla similitudine dei triangoli abc, bfg si ha: bf : ab = fg : bc ovvero, essendo bc=gh, bf : ab = fg : gh. poiché le misure di bf e ab sono due numeri consecutivi della successione di fibonacci ( , ) il rapporto bf : ab approssima il numero aureo Φ = , … (cfr. parag. ). cosicché possiamo scrivere fg : gh = Φ qualunque sia l’apertura fh fra le aste estreme del compasso. adalbert goeringer, der goldene schnitt, paperback – figura - il compasso di goeringer. https://www.amazon.com/s/ref=dp_byline_sr_book_ ?ie=utf &text=adalbert+goeringer&search-alias=books&field-author=adalbert+goeringer&sort=relevancerank is the golden section a key for understanding beauty? part ii la sezione aurea nel pentagono e nel decagono regolare mostreremo ora in qual modo la sezione aurea sia presente nel pentagono e nel decagono regolare. iniziamo dal decagono regolare e supponiamo risolto il problema della sua costruzione con riga e compasso inscrivendolo nel cerchio di raggio oa (figura a). l’angolo al centro bôa misura ° in quanto insiste sull’arco ab che è la decima parte dell’intera circonferenza. il triangolo abo è isoscele essendo oa = ob in quanto raggi della stessa circonferenza. pertanto è oÂb = ab̂o = °. tracciata la bisettrice dell’angolo ab̂o sia c il suo punto di intersezione con oa. essendo oÂb = ° e ab̂c = ° risulta bĉa = °. dunque il triangolo abc è isoscele ed è ab = bc. i triangoli abo e abc sono simili, avendo entrambi un angolo di ° e due di °. gli angoli corrispondenti sono: ab̂c = bôa = °, oÂb = ° (comune ai due triangoli), ab̂o = bĉa = °. pertanto si ha: oa : ab = ab : ca e anche ab = bc = oc in quanto il triangolo ocb è isoscele sulla base bo. dunque possiamo scrivere infine: oa : oc = oc : ca e concludere che il lato del decagono regolare è la parte maggiore della sezione aurea del raggio del cerchio circoscritto essendo oc congruente con il lato ab del decagono. possiamo anche concludere che un qualsiasi triangolo isoscele con angolo al vertice di ° è aureo, in quanto la base è la parte maggiore della sezione figura – triangolo aureo: aob nel decagono (a) e adb nel pentagono (b) regolare. a b franco eugeni and luca nicotra aurea di ciascuno dei lati uguali, ovvero il rapporto fra ciascuno dei lati uguali e la base è Φ = , … il triangolo aureo si trova anche nel pentagono regolare: è ciascuno dei triangoli isosceli aventi per base un lato del pentagono e per lati uguali due diagonali (figura b). infatti, considerato per esempio uno di tali triangoli, abd, l’angolo alla circonferenza bd̂a è la metà dell’angolo al centro bôa che insiste sullo stesso arco ab, ma è bôa = ° in quanto l’arco ab è la quinta parte dell’intera circonferenza e pertanto bd̂a = °. inoltre essendo da= bd in quanto diagonali del pentagono, il triangolo abd risulta isoscele sulla base ab e pertanto risulta dÂb = ab̂d = °. possiamo allora concludere che il lato del pentagono regolare è la parte maggiore della sezione aurea della diagonale. inoltre, tracciando la bisettrice di uno dei due angoli di ° si ottiene un nuovo triangolo isoscele con angolo al vertice di ° e angoli alla base di °, ovvero si ottiene un altro triangolo aureo dal quale si può ottenere ancora un altro triangolo aureo, e così via all’infinito. si ritrova, dunque, nel triangolo aureo lo stesso meccanismo di autorigenerazione all’infinito che abbiamo già riscontrato nel rettangolo aureo, fenomeno evidentemente legato alla natura irrazionale del rapporto che definisce la sezione aurea. il risultato raggiunto ci permette di costruire il decagono regolare inscritto in un cerchio di dato raggio ab. sul segmento ab ripetiamo la costruzione della parte maggiore della sezione aurea di ab vista precedentemente all’inizio del paragrafo : otteniamo il segmento as, lato del decagono regolare (figura figura – costruzione del decagono (a) e del pentagono (b) regolare inscritti in un cerchio. is the golden section a key for understanding beauty? part ii a). quindi tracciata la mediana di as facendo centro in a con apertura ab con il compasso possiamo individuare il centro o del cerchio circoscritto al decagono e disegnarlo. successivamente facendo centro in s con apertura del compasso sa si traccia un arco di circonferenza che interseca il cerchio nel vertice del decagono successivo ad s. ripetendo lo stesso procedimento si trovano tutti i successivi vertici del decagono. per costruire il pentagono regolare inscritto nello stesso cerchio basta congiungere fra loro uno si e uno no i dieci vertici del decagono (figura b). la sezione aurea e la spirale logaritmica la sezione aurea risulta collegata alla spirale logaritmica proprio tramite il numero aureo (Φ o φ). la spirale logaritmica, in coordinate polari ha equazione: ρ = a ebθ, che in forma logaritmica si scrive: θ = ( /b) ln (ρ/a) ed è detta anche “spirale proporzionale” poiché la distanza radiale fra le successive spire aumenta proporzionalmente all’angolo di rotazione, a differenza della spirale di archimede nella quale invece rimane costante. le la spirale logaritmica fu scoperta indipendentemente e quasi contemporaneamente da evangelista torricelli ( - ) e da rené descartes ( - ) nel . successivamente il grande matematico jacob bernoulli ( - ) rimase talmente affascinato dalle sue proprietà da chiamarla spira mirabilis e dedicarle anni di studio. sarebbe più appropriato chiamarle spirali esponenziali. da qui il nome di spirali logaritmiche. le spirali logaritmiche godono di numerose proprietà, investigate dal grande matematico jacob bernoulli. fra esse: ) è una curva congruente a tutte le sue evolute successive; ) è congruente alla sua antevoluta; ) se si pone il lume nel suo polo, anche le caustiche di riflessione e di rifrazione sono curve ad essa congruenti. la prima proprietà (auto somiglianza), esprime la congruenza della curva a se stessa a meno di trasformazioni di similitudine ed è così evidenziata da bernoulli: «aut, si mavis, quia curva nostra mirabilis in ipsa mutatione semper sibi constantissime manet similis et numero eadem, poterit esse vel fortitudinis et constantiae in adversitatibus; vel etiam carnis nostrae post varias alterationes, et tandem ipsam quoque mortem, ejusdem numero resurrecturae symbolum; adeo quidem, ut si archimedem imitandi hodienum consuetudo obtineret, libenter spiram hanc tumulo meo juberem incidi cum epigraphe: eadem numero mutata resurgo». (citazione tratta da gino loria, curve piane speciali algebriche e trascendenti, vol. ii, milano, hoepli, , p. ). dal punto di vista meccanico, la spirale di archimede può pensarsi generata da un punto che si muove a velocità costante lungo una semiretta che contemporaneamente ruota con velocità angolare costante attorno alla sua origine. nella spirale logaritmica, invece, il punto si franco eugeni and luca nicotra costanti che figurano nell’equazione in forma polare hanno il seguente significato: a è il valore “iniziale” del raggio vettore ρ in corrispondenza di θ = ; b è invece il fattore di accrescimento della spirale. infatti si ha: ρ(θ+ π) = aeb(θ+ π)= a ebθe πb = ρ(θ)e πb, da cui si conclude che la distanza radiale fra le spire successive della spirale logaritmica, ad ogni giro, aumenta secondo una progressione geometrica di ragione e πb, cioè è costante e uguale a e πb il rapporto fra le distanze dei punti della spirale situati in spire successive e di uguale anomalia (modulo π). la spirale aurea è un particolare tipo di spirale logaritmica, essendo per essa il fattore di accrescimento proprio il numero aureo: b = Φ = , …. molti oggetti naturali (galassie, disposizione delle foglie negli alberi, muove di moto uniformemente accelerato lungo la semiretta. in particolare la velocità del punto lungo la semiretta aumenta proporzionalmente all’angolo di rotazione (quindi anche proporzionalmente al tempo essendo uniforme il moto circolare della semiretta attorno alla sua origine). un’altra proprietà caratteristica delle spirali logaritmiche è l’inclinazione costante rispetto a qualunque retta uscente dal polo, per cui esse sono dette anche “spirali equiangole”. in altri termini, la tangente alla spirale logaritmica, in ogni suo punto, mantiene la stessa inclinazione rispetto alla congiungente il punto con il polo. l’inclinazione della spirale logaritmica è regolata dal fattore di accrescimento “b”ed è: arctan ( /ln b). nelle spirali auree tale inclinazione è arctan ( /ln , ) cioè è determinata dal numero aureo. fig. – a sinistra la costruzione esatta della spirale logaritmica e a destra la costruzione della spirale aurea approssimata da archi di circonferenza. is the golden section a key for understanding beauty? part ii conchiglie, ecc..) hanno la forma di spirali auree. in figura sono riportate a sinistra la costruzione esatta della spirale logaritmica e a destra la costruzione della spirale aurea approssimata con archi di circonferenza inscritti nei quadrati aventi per lato la dimensione minore di successivi rettangoli aurei. la sezione aurea e la successione di fibonacci in stretta connessione con la sezione aurea è la cosiddetta successione di fibonacci: , , , , , , ... leonardo pisano bigollo, detto fibonacci ( ?- ?), si può ritenere il più grande matematico europeo del medioevo e oggi è ricordato soprattutto perché, nel xix secolo, lucas chiamò con questo nome una successione che si presenta in un problema del suo liber abbaci. la prima edizione di questa opera ( ) è andata perduta ma nel fibonacci ne elaborò una seconda, di cui sono rimaste tre copie quasi complete, su richiesta del suo maestro, scottas, astrologo di corte dell’imperatore federico ii. a tal fine è interessante conoscere l’esistenza di un giornale trimestrale della fibonacci association, the fibonacci quarterly, che ancora oggi si occupa delle rappresentazioni dei numeri di fibonacci, delle sue proprietà e altro. nel xiv capitolo del liber abbaci leonardo pisano ( -?) propone al lettore un curioso problema la cui domanda finale è: «quot paria cuniculorum ex uno pario in uno anno germinentur?». si tratta di risolvere il seguente quesito: un allevatore ha una coppia di conigli adulti (maschio e femmina). quante coppie di conigli troverà dopo un anno, supponendo che ogni mese una coppia generi una nuova coppia (maschio e femmina) che dal secondo mese di vita diventa produttiva, e che nessun coniglio muoia? si può costruire un successione numerica intrigante: ... , , , , , , , , , , , , per quanto detto, è più esatto specificare “spirali auree”. la scrittura corretta è liber abbaci e non come spesso si legge liber abaci. la traduzione del titolo corretto è libro del calcolo e non libro dell'abaco, facendo riferimento al titolo errato liber abaci. infatti il libro fu scritto da leonardo pisano per far conoscere il nuovo modo di calcolare reso possibile dalla notazione posizionale decimale (indo-arabica) in contrapposizione al vecchio modo di calcolare con l'uso dell'abaco. l'errata traduzione nasce dalla confusione fra i termini abacus e abbacus: il primo indica l'abaco, mentre il secondo indica l'algoritmo ovvero (come veniva chiamata in quell'epoca) la tecnica di calcolo con le dieci cifre del sistema posizionale indo-arabico (cfr. keith devlin, i numeri magici di fibonacci, milano, bur rizzoli, , pp. , . titolo originale: the man of numbers). franco eugeni and luca nicotra la cui regola di costruzione è esprimibile mediante il seguente sistema ricorrente: È noto come il termine generico fn può essere calcolato con l’uso di formule dirette. la prima di esse fu scoperta da abraham de moivre ( – ) ma prende il nome da jacques philippe marie binet ( - ) che la rese nota: formula binomiale: il profondo legame fra la sezione aurea e la successione numerica fn è espresso dal rapporto fra termini consecutivi. infatti: e dunque: il numero aureo risulta, dunque, il limite all’infinito della successione numerica formata dai successivi rapporti fra due numeri consecutivi della serie di fibonacci. già dopo il ° termine della serie di fibonacci, tale rapporto si stabilizza su un valore molto prossimo al numero aureo. per tale motivo la successione di fibonacci può essere considerata (per termini sempre più grandi) anche una progressione geometrica avente per ragione il numero aureo.    == += −− ; ff fff nnn                 − +         + = nn nf   −       − == , kk kknn k kn ff ... . ... = − =⎯→⎯ → −  n n n f f ... . ... = + =⎯→⎯  → − n n n f f ( )( ) nnn nf −+= is the golden section a key for understanding beauty? part ii proponiamo ora una possibile generalizzazione della successione numerica di fibonacci. generalizziamo il sistema alle ricorrenze che definisce la successione numerica di fibonacci nel seguente sistema, sempre omogeneo a coefficienti costanti: che consente di ottenere una nuova successione i cui termini sono: e che oltre al caso particolare di fibonacci (per a= , b= , p= , q= ) presenta altri casi notevoli: a= , b= , p= , q= numeri di lucas; a= , b= , p= , q= numeri di pell; a= , b= , p= , q= numeri di pell-lucas; a=m, b= , p= , q= numeri di fibonacci generalizzati; a=m, b= , p= , q=m numeri di lucas generalizzati. l’analogo della formula di binet, dopo opportuni calcoli, è però naturalmente dipendente dai valori particolari che assumono le costanti a, b, p, q. anzi nella ricerca delle soluzioni - tra le progressioni geometriche - si possono distinguere tre casi a seconda che le radici della equazione polinomiale associata ( h = ah + b ) siano reali e distinte, reali e coincidenti, complesse e coniugate. a noi interessa soltanto il primo caso, che si verifica quando a + b > . in tale situazione la soluzione può essere così espressa: si evince allora come i rapporti fra termini consecutivi della nuova successione siano ancora una volta convergenti verso valori abbastanza singolari: per i quali valgono le identità seguenti:    == += −− qhph bhahh nnn , ( ) ( ,)(,,, qbaabpaqbpqph n +++= ) ,...) ()( qabapbba +++ +         ++         + − += n n baa ba apqp h n baa ba apqp         +−         + − − b aba h h ba n n , −+=→−  ba baba , ,   =+ , aba h h ba n n ++=→ − ba ba b a , , =  + franco eugeni and luca nicotra e inoltre: la cui verifica è una semplice conseguenza della natura dei due numeri: ovviamente si può riscrivere la stessa soluzione per hn in termini di tali rapporti, cioè: procedendo in modo analogo al caso particolare (cfr. parte prima del presente lavoro) si possono scrivere interessanti formulazioni alternative utilizzando frazioni continue: e radici continue: valida se a > - √𝑏 valida se a < √𝑏. ,, = baba  ab baba =− ,,  ( ) +         + − += n ban ba apqp h , ( )n ba b ba apqp , −         + − − baba ,, ,  ... , + + + + = a b a b a b a ba ... , + + + + += a b a b a b a b aba ..., ++++= babababba ... , −−−−= bb a bb a bb a b ba is the golden section a key for understanding beauty? part ii così si possono considerare i nuovi oggetti, proprio per la strettissima somiglianza delle loro proprietà a quelle della sezione aurea, come una naturale generalizzazione della stessa. dalla sezione aurea nella musica alla legge universale della bellezza: eco sentimentale della logica il ripetersi in natura di elementi estetici con una certa regolarità ha indotto molti studiosi a credere che essa, nelle sue multiformi espressioni, segua una “legge della bellezza”, la quale, in quanto legge naturale, deve possedere tre attributi: universalità, immutabilità e necessità. si è quindi più volte tentato di ottenere per la legge della bellezza una formalizzazione matematica, la quale soltanto può possedere queste tre caratteristiche. uno dei primi tentativi – in verità più filosofico che matematico – fu fatto dal filosofo olandese frans hemsterhuis ( - ) nel secolo xviii, il quale più che formulare una legge della bellezza ne diede la seguente definizione: «il bello presenta il massimo numero di idee nel minimo tempo». lo svizzero andreas speiser ( - ) si spinse oltre, associando ai motivi ornamentali dell’architettura classica il concetto matematico di gruppo finito. più dettagliato e analitico è stato, invece, il tentativo del matematico statunitense george david birkhoff ( – ), il quale escogitò una formula matematica per misurare la bellezza dei vasi rotondi, giungendo a risultati in accordo con il senso di bellezza che comunemente ispira la vista di questo tipo di vasi. secondo la sua formula, la bellezza di un vaso rotondo può essere “misurata” con il rapporto tra il suo “ordine” e la sua “complessità”: maggiore è tale rapporto, più il vaso è bello. birkhoff considera le curve meridiane di un vaso rotondo e, di esse, i punti notevoli che l’occhio umano facilmente rileva: i punti terminali, i punti di flesso, i punti a distanza minima e massima dall’asse di rotazione del vaso, i punti angolosi, i punti in cui la tangente è perpendicolare all’asse: il numero complessivo di tali punti costituisce la “complessità” del vaso. per “ordine” del vaso, invece, assume il numero di relazioni che intercedono fra le distanze dei punti notevoli misurate nella direzione dell’asse o in quella perpendicolare a questo. enrico bompiani, matematica e arte. periodico di matematiche, n. - , ottobre , pp. - . noto soprattutto per quello che oggi viene chiamato “teorema ergodico”. birkhoff fu uno dei matematici statunitensi più influenti della sua generazione. enrico bompiani, op cit. https://it.wikipedia.org/wiki/ https://it.wikipedia.org/wiki/ franco eugeni and luca nicotra un’analisi del bello è riscontrabile anche nella musica fin dall’antichità ed è connessa alla presenza in essa della matematica, come affermava già pitagora ( / - a. c.). la parola chiave con la quale riassumere la grande intuizione dei pitagorici è "armonia". essa va filosoficamente intesa in senso etico, matematico e musicale. i pitagorici insegnavano la musica e compresero il nesso tra musica, matematica e geometria. l’armonia è il fulcro del loro pensiero filosofico e si estende perfino ai gesti, alla politica del corpo, all'economia della vita, al modo in cui ci si comporta nei rapporti sociali. scrive jean-philippe rameau ( - ): la musica è una scienza che deve avere regole certe: queste devono essere estratte da un principio evidente, che non può essere conosciuto senza l'aiuto della matematica. devo ammettere che, nonostante tutta l'esperienza che ho potuto acquisire con una lunga pratica musicale, è solo con l'aiuto della matematica che le mie idee si sono sistemate, e che la luce ne ha dissipato le oscurità. lo stretto rapporto che intercorre tra musica e matematica secondo la scuola pitagorica risiede, come è ben noto, nella scoperta delle relazioni fra i differenti toni delle note musicali e le lunghezze della corda vibrante: mentre sono risultati esatti i rapporti numerici di pitagora fra le lunghezze delle corde corrispondenti alle diverse note, non altrettanto esatti sono i rapporti fra i pesi ovvero fra le tensioni applicate ad esse. per pitagora, infatti, le frequenze dei suoni sarebbero proporzionali ai pesi, mentre in realtà sono proporzionali alle radici quadrate dei pesi. a noi basta la notizia che già nel vi sec. a. c., da parte di pitagora o qualcun altro per lui, c’è stato un primo tentativo, in parte riuscito, di comprendere l’esistenza di rapporti numerici fra certe grandezze geometriche e fisiche che caratterizzano le diverse note musicali. È inutile dilungarsi sui particolari di questo errore, che fu posto in evidenza nel da vincenzo galilei, padre di galileo, nella sua opera discorso intorno alle opere di messer zarlino da chioggia, dove però giunse a una errata relazione fra la frequenza del suono e l’area della sezione della corda. tale errore, dovuto a un falso ragionamento e alla noncuranza di “interpellare” la natura, non poteva essere riparato che dal padre del metodo sperimentale, il figlio galileo, che finalmente nel , nei discorsi e dimostrazioni matematiche intorno a due nuove scienze, enunciò la relazione corretta che lega la frequenza fondamentale del per più dettagliati collegamenti della musica con la matematica e la scienza in generale cfr. luca nicotra, musica: ragione e sentimento. artescienza, anno iii, n. , , pp. - . jean-philippe rameau è stato un compositore, clavicembalista, organista e teorico della musica francese. ricordiamo il suo: trattato dell'armonia ridotto ai suoi principi fondamentali del . is the golden section a key for understanding beauty? part ii suono emesso da una corda alle caratteristiche fisico-geometriche della corda, che noi oggi esprimiamo sinteticamente con la formula: la storia narrata da giamblico a proposito del modo in cui pitagora, sentendo i suoni emessi dall’incudine di un fabbro, arrivò a stabilire il legame fra i diversi toni delle note emesse da una corda vibrante e la sua lunghezza ha più l’aria di una leggenda che di verità storica. sembra più verosimile, invece, che pitagora abbia compiuto degli esperimenti sul monocordo, uno strumento costituito da una sola corda, di cui poteva essere variata la lunghezza della parte vibrante. tali esperimenti gli fecero concludere, utilizzando termini moderni, che detta “fondamentale” la frequenza della corda intera liberamente vibrante, e considerato il suono da essa emesso (in termini moderni la nota musicale “do ”), la stessa corda dimezzata emette un suono di frequenza doppia (in termini moderni la nota “do ” della seconda ottava) giudicato da pitagora consonante con il primo. inoltre, risultavano a lui “gradevoli” i suoni emessi dalla stessa corda ridotta ai suoi / e ai suoi / , che sono rispettivamente un “fa” (quarta nota dell’ottava) e un “sol” (quinta nota dell’ottava). È rimarchevole il fatto che con queste quattro note (do , fa, sol, do ), scoperte da pitagora, si è potuto realizzare lo strumento a corda più diffuso e rappresentativo dell’antichità: la lira. inoltre i numeri , , , , che figurano nei rapporti delle lunghezze delle corde che emettono tali note, avevano per i pitagorici un significato particolare: la loro somma, , era il loro numero magico! ma le questioni dei rapporti tra matematica e musica sono legati anche e misteriosamente alla sezione aurea e ai numeri di fibonacci. il musicista ungherese ernő lendvai ( - ) ha analizzato le opere del famoso compositore ungherese béla janos bartók ( - ) basandosi su due sistemi opposti: la sezione aurea e la scala acustica, mentre altri studiosi di musica rifiutano questa analisi. il compositore e pianista francese erik satiè ( - ) ha utilizzato il rapporto aureo in molti dei suoi pezzi, tra cui sonneries de la rose + croix. luca nicotra, musica: ragione e sentimento, op. cit., p. . che costituiscono la scala diatonica pitagorica. ernő lendvai, béla bartók, an analysis of his music. london, ed. kahn and averill , . piotr sadowski, the knight on his quest: symbolic patterns of transition in sir gawain and the green knight, university of delaware press., , p. . satiè viene iniziato nell' ordine cbalistico dei rosa+croce, fondato da joséphin péladan e stanislas de guaita. in qualità di tesoriere prima e gran sacerdote e quindi di influente membro della confraternita, compone la sonneries de la rose-croix, les fils des étoiles. nel suo slancio mistico, che in quel periodo aveva, satie crea la sua chiesa, la Église métropolitaine d'art de jésus-conducteur e lancia anatemi contro i «malfattori che speculano franco eugeni and luca nicotra tuttavia tutti questi tentativi, pur apprezzabili, erano limitati a formalizzare la bellezza in casi particolari e non avevano quindi la caratteristica della universalità. invece, una ricerca sistematica, e a trecentosessanta gradi, di una vera e propria legge della bellezza con i caratteri della universalità, permanenza e necessità è stata compiuta negli anni ’ del secolo scorso dal filosofo siciliano carmelo ottaviano ( - ), attraverso un originale approccio filosofico-scientifico, partendo dalla applicazione della sezione aurea alla musica. i risultati dei suoi lunghi anni di studio sull’argomento sono stati raccolti ed esposti, con grandi dettagli di prove fotografiche, in un grosso volume dal titolo la legge della bellezza come legge universale della natura. ottaviano comincia la sua indagine sul “bello” proprio dalla musica, ritenendola l’arte che «racchiude in sé il segreto della bellezza nella sua espressione più completa e piena», essendo più evidente in tale disciplina ciò che può darci una sensazione di godimento estetico e per converso ciò che può darci una sensazione opposta. per tale motivo analizza in dettaglio l’accordo perfetto maggiore (accordo di terza-quinta-ottava), detto anche “perfettamente consonante” per la sua capacità di produrre una sensazione armoniosa. considerando le frequenze delle note di tale accordo riferite a quella del do : do mi sol do + / + / ottaviano nota che gli intervalli formano una progressione addizionale: intervallo do -mi intervallo mi-sol intervallo sol-do / / / sulla corruzione umana». incredibile che satiè, da student, non fu molto apprezzato dai professori, dai quali ebbe numerose critiche. considerato uno dei pensatori più originali del novecento. docente universitario già a anni, dal fu ordinario di storia della filosofia a catania, napoli e cagliari. fu anche docente di paleografia. nel a roma fondò l’importante rivista internazionale «sophia, rassegna critica di filosofia e storia della filosofia». È autore di numerosi studî sul pensiero medievale, di scritti pedagogici e di notevoli lavori teoretici, molti dei quali di critica all’idealismo, che spiegano la sua posizione defilata rispetto alla filosofia dominante in quell’epoca e ne rilanciano l’importanza nel dibattito culturale attuale. carmelo ottaviano, la legge della bellezza come legge universale della natura, padova, cedam, . la seguente parte relativa agli studi di carmelo ottaviano sulla sezione aurea e sulla legge universale della natura cui pervenne è ripresa, con qualche leggera modifica, da luca nicotra, la legge della bellezza di carmelo ottaviano. notizie in.. controluce», nn. , , , , , , anno . is the golden section a key for understanding beauty? part ii infatti, gli intervalli fra le prime tre note sono uguali ( / e / ), mentre quello relativo alle ultime due risulta essere la somma dei precedenti: / = / + / : quindi costituiscono l’inizio di una progressione addizionale, nella quale, come è noto, ciascun termine è dato dalla somma dei due precedenti, come nella progressione di fibonacci costruita a partire dalla coppia , : , , , , , , , , , , , , … ottaviano applica la stessa analisi ai colori, ricordando l’analogia fra i colori e i suoni già posta in evidenza da isaac newton: «…i colori dello spettro visibile si susseguono con gli stessi intervalli o rapporti, con cui si susseguono le note musicali». espresse in trilioni di vibrazioni al minuto, le frequenze dei colori fondamentali dello spettro luminoso risultano essere: porpora rosso arancio giallo verde azzurro violetto viola scuro che rapportate alla prima danno luogo alla stessa successione di frazioni delle frequenze delle note musicali: / / / / / / preso atto delle numerose analogie fra le note musicali e i colori fondamentali, già rilevate da altri studiosi, ottaviano applica ai colori fondamentali la stessa legge di armonia costituita dalla progressione addizionale dell’accordo perfetto maggiore: quattro colori sono intonati tra loro quando il quarto di essi differisce dal terzo per il doppio della differenza in frequenza esistente tra il primo e il secondo e tra il secondo e il terzo, uguale essendo la differenza in frequenza tra il primo e il secondo, e tra il secondo e il terzo. considera diversi esempi, fra cui la combinazione di colori porpora- arancio-verde-viola scuro la quale corrisponde all’accordo perfetto maggiore do -mi-sol-do . infatti le frequenze di quei colori (in trilioni di vibrazioni al minuto) sono: , , , e, quindi, riferite alla prima: ottaviano cita in particolare g. russo, la musica nei colori, in bollettino dell’associazione ottica italiana, n. , maggio . carmelo ottaviano, op. cit., p. . franco eugeni and luca nicotra , + / , + / , ovvero gli intervalli seguono la stessa disposizione degli intervalli dell’accordo perfetto maggiore: / , / , / il quartetto di colori porpora-arancio-verde-viola scuro è proprio quello che, con accenti molto poetici, ottaviano rileva «in uno dei più belli tra i fenomeni della natura, il sorgere dell’aurora, quando il viola scuro o nero del cielo e del mare si tinge tremolando in arancio e si smorza in verde al tocco del raggio purpureo del sole che sorge, e a mano a mano trionfa delle tenebre». proseguendo sulla stessa via, estende la sua ricerca al campo della metrica in poesia, analizzando gli intervalli sillabici dell’«endecasillabo consonante», che comporta l’accento sulla seconda, quarta e decima sillaba, giungendo a risultati analoghi a quelli ottenuti per le note musicali e per i colori. a questo punto ottaviano si chiede: «il rapporto armonico è rappresentato da una relazione necessaria parzialmente costante o uniforme tra valori numerici diversi?» trova una risposta nella sua originalissima analisi filosofica del problema, che lo porta a individuare, in aggiunta ai giudizi analitici e sintetici, un terzo tipo di giudizi che battezza con il termine «sineterico», composto dal greco sin (sýn) = con ed eteros (šteroj) = diverso. mentre nel giudizio analitico il predicato è identico al soggetto («il circolo è rotondo»), nel giudizio sintetico il predicato è diverso dal soggetto («giovanni è balbuziente»). il giudizio analitico è necessario e universale, ma è una pura tautologia in quanto afferma l’identità fra soggetto e predicato (a = a) ed è quindi infecondo poiché, di conseguenza, il predicato non aggiunge null’altro che non sia già nel soggetto. il giudizio sintetico, invece, è un giudizio fecondo, perché fornisce «intorno al soggetto una connotazione che non è implicita in esso, e quindi accresce il nostro sapere». il rapporto fra predicato e soggetto, in esso, non è però necessario e universale. il fatto di essere giovanni non implica necessariamente l’essere balbuziente e non tutti i giovanni sono balbuzienti. il giudizio sintetico, dunque, è accidentale e contingente. i due tipi di giudizi hanno, pertanto, qualità complementari ma – osserva ottaviano – «se la scienza umana non disponesse che di questi due tipi di giudizi, sarebbe senz’altro impossibile». il geniale filosofo siciliano indica proprio nel giudizio sineterico l’unico tipo «con cui la mente umana ragiona, cioè da un lato pensa concetti e non parole, e dall’altro inventa e scopre carmelo ottaviano, op. cit., p. . is the golden section a key for understanding beauty? part ii relazioni o leggi nuove». il giudizio sineterico, infatti, esprime la «connessione necessaria (sýn) nella diversità logica (šteroj) tra soggetto e predicato». oltre ai giudizi sineterici ottaviano individua anche dei «nessi sineterici». mentre i primi constano di due membri (soggetto e predicato), i secondi constano di tre o quattro membri fra i quali quindi intercedono due o tre relazioni. i nessi sineterici sono per ottaviano veri e propri tipi di ragionamento, poiché collegano tra loro giudizi sineterici. giunge così a una prima conclusione: orbene - e questo è il punto che merita particolare attenzione - la legge che regola i fenomeni del bello, sia naturale che artistico, è proprio una legge di tipo sineterico, e precisamente della struttura a duplice o a triplice rapporto, e a tre o quattro membri o facce, come abbiamo visto. l’accordo perfetto maggiore ci rivela infatti un legame necessario tra le quattro note do , mi, sol, do , evidentemente diverse tra loro, legame dal quale nasce un rapporto triplice formalmente, duplice contenutisticamente, negli intervalli / , / , / , e triplice sia formalmente che contenutisticamente nei valori , , delle frequenze delle vibrazioni secondo il corista normale, tutti e tre diversi tra loro. e trae la seguente conclusione filosofica: tutte le espressioni del bello in tutte le arti sono rappresentate da nessi sineterici, quegli stessi nessi cioè con cui la mente umana ragiona e inventa o scopre nell’intero ambito del sapere scientifico. il che significa: la bellezza non è che l’espressione della razionalità o logicità dal punto di vista del sentimento: per così dire, l’eco sentimentale della razionalità o logica. l’analisi logico-filosofica-scientifica delle espressioni di bellezza conduce ottaviano a individuare una legge comune a tutte le arti (scultura, architettura, poesia, pittura) e quindi a connetterla tramite la logica a tutte le discipline dello scibile umano. infine, dimostra l’universalità della legge trovata mostrandone l’applicabilità, oltre che al mondo delle arti, anche al mondo organico e inorganico, trovando ivi la sua espressione geometrica nella spirale logaritmica aurea, già da tempo, tuttavia, presa come modello matematico della bellezza. della spirale aurea ottaviano considera la costruzione approssimata tramite il rettangolo aureo, già presente in alcuni lavori di jay hambidge e di carmelo ottaviano, op. cit., pp. - . i corsivi sono nel testo originale. carmelo ottaviano, op. cit., p. . franco eugeni and luca nicotra john crawford pierce, e fa rilevare esplicitamente che essa è costituita di quarti di circonferenza raccordati tangenzialmente e aventi raggi che si incrementano secondo la successione di fibonacci. la curva così costituita è da lui assunta come curva della bellezza. i successivi rettangoli aurei utilizzati per la sua costruzione sono stati ottenuti ciascuno sommando al precedente rettangolo aureo un quadrato di lato pari al lato maggiore di questo. per esempio, il rettangolo aureo aefd (figura ) è ottenuto sommando al rettangolo aureo befc il quadrato abcd di lato uguale al lato maggiore bc del rettangolo befc. È facile verificare che ogni arco circolare che compone la spirale ha raggio uguale alla somma dei raggi dei due archi precedenti. per esempio, l’arco ac ha raggio bc = bg + gc = li + gc (essendo bg = li) e così via. inoltre, i raggi degli archi circolari componenti costituiscono una progressione geometrica avente come ragione il numero aureo: infatti il rapporto fra due raggi consecutivi è il rapporto fra i lati consecutivi di un rettangolo aureo. per esempio, bc/gh = Φ, essendo bc e be = gh i lati maggiore e minore del rettangolo aureo befc. jay hambidge, the elements of dynamic symmetry, new haven, yale university press, . agli studi dell’hambidge (oltre che al numero aureo) si riferisce ampiamente ugo maraldi in un suo articolo intitolato il numero della bellezza. l’illustrazione del medico, gennaio , pp. - ; cfr. anche john crawford pierce, the fibonacci series. scientific montly, october , pp. - . figura - costruzione approssimata della spirale aurea con rettangoli aurei. is the golden section a key for understanding beauty? part ii ottaviano, in quanto filosofo, non si accontenta di trovare i nessi causali tra i fenomeni e s’interroga sul perché ultimo di tali nessi: se tutto il mondo organico e inorganico segue una legge della bellezza, perché ciò deve accadere necessariamente? la progressione addizionale – ovvero la generica successione numerica generata dalla formula di ricorrenza un = u n- + u n- – è per ottaviano, in ultima analisi, la vera legge matematica della bellezza, nella sua forma aritmetica. infatti, in tutte le progressioni addizionali – ed è questa una sua scoperta originale – il rapporto fra un termine e il successivo tende indefinitamente al numero aureo φ = , … ottaviano considera, in aggiunta a quella di fibonacci, altre sei diverse progressioni addizionali: quella di hambidge costruita a partire da e , e cinque costruite da lui stesso a partire da e , e , e , e , e . ottaviano prima costruisce le due progressioni addizionali intermedie fra quella di fibonacci e quella di hambidge, poi va oltre quest’ultima costruendo le progressioni a partire da e , e , quindi intuendo la loro proprietà comune ne sceglie a caso un'altra: quella costruita da e . per tutte verifica che il rapporto fra un termine e il successivo tende al numero aureo , . quindi generalizza affermando: la progressione di fibonacci e la progressione di schimper-braun, o della fillotassi, rientrano dal punto di vista algebrico come casi particolari nella “teoria dei limiti”: per qualunque successione, ottenuta partendo da due numeri qualsiasi e sommando successivamente i due elementi precedenti, il limite di un elemento diviso per il successivo coincide con la parte aurea di . e conclude da filosofo: ciò non può significare se non questo: tutte le progressioni addizionali sono da considerare come espressioni successivamente approssimate della relazione designata con il termine di “sezione aurea di un segmento”. È questo particolare modo di divisione dell’unità in parti disuguali che costituisce l’essenza della legge della bellezza nella sua espressione aritmetica. ma perché la natura, e inconsapevolmente l’uomo nell’uniformarsi a questa legge naturale e quindi universale, fra gli infiniti modi di dividere tuttavia soltanto intuita e verificata per alcuni casi particolari. la dimostrazione matematica rigorosa generale è dovuta invece a franco eugeni e raffaele mascella, pubblicata per la prima volta nell’articolo a note in generalize fibonacci numbers, journal of discrete mathematical sciences and cryptography v. , n. , , pp. - carmelo ottaviano, op. cit., p. . per «parte aurea di » ottaviano intende il numero aureo φ = . … carmelo ottaviano, op. cit., p. . il corsivo è nel testo originale. franco eugeni and luca nicotra l’intero in parti disuguali sceglie proprio il dividere secondo la “media ed estrema ragione”, propria della sezione aurea? ottaviano trova la ragione di ciò nella conservazione di una simmetria (dinamica) pur nella diversità delle parti, cioè nel ripetersi sempre identico a se stesso del procedimento di divisione: questo è l’unico modo razionale secondo cui si possa dividere un segmento in due parti disuguali, essendo un procedimento simmetrico, cioè che si ripete identico a intervalli regolari, pur variando la grandezza degli elementi tra cui esso si pone. dividendo invece il segmento secondo qualsiasi altro procedimento, si ottiene una varietà di risultati non retti da alcuna simmetria, cioè si ottiene una molteplicità disordinata, caotica. la sezione aurea appare a ottaviano il «procedimento obbligato» di divisione dell’unità in parti disuguali, per una duplice «interiore giustificazione logica». in primo luogo per il principio di ragion sufficiente: non esiste un motivo valido per cambiare procedimento e non mantenerlo uniforme nelle successive divisioni delle parti. inoltre, per il principio economico del massimo rendimento: con esso si «ottiene il massimo risultato, la molteplicità simmetrica invece di quella asimmetrica, con il minimo mezzo». ma se la regolarità spaziale della divisione dinamica in parti disuguali della sezione aurea (il rapporto fra le parti rimane infatti lo stesso pur variando le dimensioni delle parti) rende conto della bellezza nelle opere dell’uomo e, in natura, nel mondo inorganico, v’è un’altra ragione ancora che ne giustifica l’«obbligato» uso da parte della natura negli esseri viventi. È la dinamica stessa dell’accrescimento – caratteristico dello sviluppo di un essere vivente – che «richiede una legge della crescita o sviluppo del vivente stesso (il vivente è tale in quanto cresce), e se la crescita suppone un rapporto di parti disuguali, cioè un procedimento per divisione in parti disuguali, quale divisione in parti disuguali la natura potrebbe scegliere, se non quella che si impone per una ragione logica o necessaria, cioè la divisione in media ed estrema ragione, ossia il rapporto che nasce dal procedimento addizionale?» dunque la sezione aurea e le progressioni addizionali, che ad essa conducono come limite dei rapporti fra termini successivi, sono certamente la base dell’armonia, ma in ultima analisi sono soprattutto finalizzate a permettere la vita. e così come per il fisico teorico paul dirac la bellezza porta alla verità, per ottaviano la bellezza porta alla vita: carmelo ottaviano, op. cit., p. . carmelo ottaviano, op. cit., p. . carmelo ottaviano, op. cit., p. . is the golden section a key for understanding beauty? part ii infine, in quanto legge dello sviluppo della natura vivente, il rapporto della serie addizionale mostra di essere un rapporto finalizzato, ossia ordinato a sviluppare la vita, in altri termini a diffondere la vita. ciò significa che lo sviluppo della vita nasce dalla ragione stessa, in quanto lo stesso ritmo di questa (il giudizio sineterico) comanda il ritmo di quella (il procedimento addizionale). non è quindi dubbio che la bellezza rappresenti la condizione ideale della vita, il maggiore possibile trionfo della vita sulla morte. ottaviano, tramite diverse centinaia di fotografie di soggetti vari, fornisce la dimostrazione dell’applicabilità della curva della bellezza a tutti gli enti naturali, viventi e non-viventi: piante, fiori, pesci, insetti, uccelli, rettili, mammiferi, lo scheletro, gli organi del corpo umano e animale, onde, cascate, correnti marine, coste, scogli, banchi coralliferi, nubi, eruzioni della corona solare, macchie solari, testa delle comete, aurore boreali, l’occhio dei cicloni e degli uragani, microrganismi e galassie. sovrapponendo la spirale aurea con le immagini di numerosi esempi di tali categorie di enti ritenuti belli, ottaviano avvalora il suo asserto secondo il quale le loro forme sono delineate da tratti di quella spirale e mostra come, al contrario, le forme di oggetti o esseri viventi giudicati brutti o malati devino da essa (figure - ). risulta difficilmente spiegabile come pura coincidenza questo ampio e multiforme richiamo alla sezione aurea, alla progressione di fibonacci e alla spirale aurea, non tanto nell’opera dell’uomo quanto piuttosto in natura. insomma, si ripresenta, anche in questo caso, l’insoluta questione di quanto della verità matematica è in noi e quanta è fuori di noi. dilemma che riguarda il fisico più che il matematico – che a differenza del primo può ritenersi soddisfatto della sua costruzione, anche se non corrispondente alla realtà fisica, purché logicamente corretta – e tanta meraviglia suscitava in albert einstein: «la matematica non smetterà mai di stupirmi: un prodotto della libera immaginazione umana che corrisponde esattamente alla realtà». il sommo galilei, invece, nella sua opera il saggiatore non mostra a tal riguardo alcun dubbio: la matematica è nella natura: la filosofia è scritta in questo grandissimo libro che continuamente ci sta aperto innanzi a gli occhi (io dico l’universo)» che «è scritto in lingua matematica, e i caratteri son triangoli, cerchi, ed altre figure geometriche, senza i quali mezzi è impossibile a intenderne umanamente parola; senza questi è un aggirarsi vanamente per un oscuro labirinto. carmelo ottaviano, op. cit., p. . carmelo ottaviano, op. cit. “appendice figure”. galileo galilei, il saggiatore, vi, . franco eugeni and luca nicotra concetto ripetuto in tempi più recenti dal grande fisico-matematico richard feynman ( - ): a quelli che non conoscono la matematica è difficile percepire come una sensazione reale la bellezza, la profonda bellezza della natura ... se volete conoscere la natura, apprezzarla, è necessario comprendere il linguaggio che essa parla. richard feynman, the character of physical law. figure , , , – da carmelo ottaviano, la legge della bellezza come legge universale della natura, padova, cedam, fig. , fig. , fig. , fig. . is the golden section a key for understanding beauty? part ii figure , , , – da carmelo ottaviano, la legge della bellezza come legge universale della natura, padova, cedam, , fig. , fig , fig. , fig. . franco eugeni and luca nicotra figure , , – da carmelo ottaviano, la legge della bellezza come legge universale della natura, padova, cedam, , fig. , fig , fig. . is the golden section a key for understanding beauty? part ii bibliografia berardi l., beutelspacher a. ( ). il pentagono regolare e la sezione aurea. periodico di matematiche. serie vi, vol. , n. , roma. bompiani e. ( ). matematica e arte. periodico di matematiche, n. - , ottobre , pp. - . crawford pierce j. c. ( ). the fibonacci series. scientific montly, october , pp. - . devlin k. ( ). i numeri magici di fibonacci, milano, bur rizzoli, , pp. , . titolo originale: the man of numbers. enriques f., amaldi u. ( ). elementi di geometria, parte seconda. bologna, zanichelli, p. . eugeni f., mascella r. ( ). a note in generalize fibonacci numbers. journal of discrete mathematical sciences and cryptography v. , n. , pp. - . feynman r. p. ( ). the character of physical law. modern library. galilei g. ( ). il saggiatore, vi, . goeringer a. ( ). der goldene schnitt, paperback . hambidge j. ( ). the elements of dynamic symmetry, new haven, yale university press. lendvai e., bartók b. ( ). an analysis of his music. london, ed. kahn and averill. loria g. ( ). curve piane speciali algebriche e trascendenti, vol. ii, milano, hoepli. maraldi u. ( ). il numero della bellezza. l’illustrazione del medico, gennaio , pp. - . nicotra l. ( ). la legge della bellezza di carmelo ottaviano. notizie in...controluce, nn. , , , , , , . nicotra l. ( ). musica: ragione e sentimento. artescienza, anno iii, n. , pp. - . nicotra l. ( ). osservazioni critiche sulla sezione aurea. convegno “matematica, natura, architettura”, novembre , mathesis- dipartimento di architettura, napoli. ottaviano c. ( ). la legge della bellezza come legge universale della natura. pavia, cedam. https://www.amazon.com/s/ref=dp_byline_sr_book_ ?ie=utf &text=adalbert+goeringer&search-alias=books&field-author=adalbert+goeringer&sort=relevancerank franco eugeni and luca nicotra russo g. ( ). la musica nei colori. bollettino dell’associazione ottica italiana, n. , maggio . sadowski p. ( ). the knight on his quest: symbolic patterns of transition in sir gawain and the green knight, university of delaware press., p. . j. funct. biomater. , , ; doi: . /jfb www.mdpi.com/journal/jfb article skin-compatible biobased beauty masks prepared by extrusion maria-beatrice coltelli , ,*, luca panariello , , pierfrancesco morganti , , serena danti , adone baroni , , andrea lazzeri , , alessandra fusco , and giovanna donnarumma , ,* consorzio interuniversitario nazionale per la scienza e tecnologia dei materiali (instm), florence, italy; luca.panariello@ing.unipi.it (l.p.); adone.baroni@unicampania.it (a.b.); andrea.lazzeri@unipi.it (a.l.); alessandra.fusco@unicampania.it (a.f.) department of civil and industrial engineering, university of pisa, pisa, italy; serena.danti@unipi.it academy of history of health care art, rome, italy; pierfrancesco.morganti@iscd.it dermatology department, china medical university, shenyang , china department of experimental medicine, university of campania “luigi vanvitelli”, naples, italy * correspondence: maria.beatrice.coltelli@unipi.it (m.-b.c.); giovanna.donnarumma@unicampania.it (g.d.); tel.: + - - (m.-b.c.) received: january ; accepted: march ; published: april abstract: in the cosmetic sector, natural and sustainable products with a high compatibility with skin, thus conjugating wellness with a green-oriented consumerism, are required by the market. poly(hydroxyalkanoate) (pha)/starch blends represent a promising alternative to prepare flexible films as support for innovative beauty masks, wearable after wetting and releasing starch and other selected molecules. nevertheless, preparing these films by extrusion is difficult due to the high viscosity of the polymer melt at the temperature suitable for processing starch. the preparation of blends including poly(butylene succinate-co-adipate) (pbsa) or poly(butylene adipate-co-terephthalate) (pbat) was investigated as a strategy to better modulate melt viscosity in view of a possible industrial production of beauty mask films. the release properties of films in water, connected to their morphology, was also investigated by extraction trials, infrared spectroscopy and stereo and electron microscopy. then, the biocompatibility with cells was assessed by considering both mesenchymal stromal cells and keratinocytes. all the results were discussed considering the morphology of the films. this study evidenced the possibility of modulating thanks to the selection of composition and the materials processing of the properties necessary for producing films with tailored properties and processability for beauty masks. keywords: starch; poly(hydroxyalkanoate); biopolyesters; beauty masks; releasing; skin compatible . introduction over the past two decades, declining fertility and mortality rates have resulted in an increased aged population [ ]. this phenomenon has created room for innovation, leading to a robust demand for anti-aging products in order to prevent wrinkles, age-spots, dry skin, uneven skin tone and even hair weakening. by , in fact, the worldwide population over years of age is expected to reach . billion: the life expectancy for women has been predicted to rise from . years in to . in , while for men this increase is expected to be from . to . years. as a consequence, new demographic trends, technologies, and consumer insights are impacting the cosmetic sector that has shown a general resistance to macroeconomic events such as recession [ ]. thus, today the global beauty industry reached a value of $ billion, with the largest market j. funct. biomater. , , of represented by the us (with about % share), followed by china ( %) and japan ( %). with a compound annual growth rate between % and %, the beauty market is estimated to reach $ billion by , remaining impervious to the ups and down of the global economy [ , ]. however, while % of women aged more than years old want to see more beauty products targeting anti-aging issues, more specific men’s personal care products are also emerging. moreover, consumers are increasingly demanding about the real composition of the products they are buying, and they wish to have more information regarding the use of the different cosmetics and beauty products that work both internally and topically, being less interested in the usual advertising and marketing announcements. thus, ingredient sourcing and effectiveness have become a major concern for the cosmetic industry together with the use of recyclable and refillable packaging materials necessary to reduce their carbon footprint, especially if obtained by industrial and agro-food waste. in the cosmetic sector, the consumers’ naturally oriented demand is towards the use of biobased active molecules and materials; this so called clean and natural beauty, therefore, is not only about what is in consumers’ products, but also about how products are produced and packaged. in conclusion, in moving the raw materials from waste and/or land to the lab, biotechnologies are increasingly impacting the production of future beauty ingredients as well as the final products. biobased materials to make innovative beauty masks go in this direction because such renewable raw materials seem able to protect the skin from pollution and modulate its microbiota [ ]. for all these reasons, the production of more and more commercial products made by biobased and biodegradable polymers [ ] (especially those products having a brief life-cycle) can be no longer delayed. beauty masks are currently mainly produced by using wet, nonwoven tissues, often prepared with fossil-based fibers. after their use, these products and their packaging materials are not selectively collected, contributing to increase the nondifferentiated part of the urban waste, often incinerated or landfilled. biobased and biodegradable polymeric materials, with the capacity of adhering to skin after wetting and releasing active molecules that are skin-friendly and easily compostable after usage, represent highly eco-sustainable options and at the same time meet consumers’ expectations. they can be commercialized at the dry state, avoiding the use of preservatives [ – ]. moreover, they can effectively release starch [ ] together with the functional molecules previously added by several techniques to the starch or to the obtained film, for instance as coating. among the biobased polymers already available on the market, poly(hydroxyalkanoates) (phas), a family of polymers obtained from bacteria [ ], are suitable for this application because of their very high biocompatibility [ , ], lower greenhouse gas emissions [ ] and both soil and marine compostability [ , ]. these properties make the pha-based materials very promising to be used in applications where environmental concern and biocompatibility are both fundamental. on the other hand, starch is the major carbohydrate reserve in higher plants [ ] and is also a very abundant biopolymer still much used in nonfood applications (e.g., glues, gums, thickener, soothing for skin). skin-compatible pha/starch films including calcium carbonate were prepared in a previous paper [ ], where a pha elastomer (em f em f, obtained from shenzhen ecomann biotechnology co.), a specific calcium carbonate and an easy methodology to pregelatinize starch were investigated and selected for preparing films by compression molding. these films resulted as promising to make beauty masks being flexible enough to follow the skin curvature, being sticky when applied on wet skin and having a fast release kinetic in water. however, their preparation was based on compression molding of biopolymeric powder with calcium carbonate as additive. this methodology is different from the ones currently used in industry to prepare bioplastic flat films characterized by a high productivity [ – ] and therefore can limit the real feasibility of the process. j. funct. biomater. , , of moreover, the preliminary extrusion of the blend consisting of pha, starch and calcium carbonate showed a high value of torque in agreement with a high viscosity of the melt. therefore, the processing should be made easier to allow the use of these biobased films in industrial applications. poly(hydroxybutyrate) (phb), the most investigated biopolyester of the pha family, has a limited stability at the high temperatures required for the melting processes. it, in fact, undergoing thermal degradation affects its physical and mechanical properties, making the industrial process difficult [ ]. the very low resistance to thermal degradation seems to be the most serious problem related to its processing. the main reaction involves chain scission, which results in a rapid decrease in molecular weight [ ]. copolymers of -hydrobutyrate with other hydroxyacids present a lower melting point and an increased processing window. however, the critical molecular weight of these polymers is high [ ] and, when processed, it is necessary to control the temperature, keeping it slightly above the melting point to avoid the polymer degradation. therefore, plasticization is generally adopted as the methodology to control the processing temperature [ ]. the blending of pha, especially phb with starch, has been extensively investigated [ , ]. godbole et al. [ ] discussed the compatibility of phb with starch to achieve the improved properties and reduce cost. the results revealed that films had a single glass transition temperature (tg) for all proportions of phb/starch blends. however, the necessity of increasing the compatibility of phb and pha with starch is evidenced in other papers, and several methodologies including the chemical modification of polymers are proposed [ , ]. the blending with copolyesters having a low viscosity in the processing temperature window of pha seems to be a good strategy to enhance processability. elastomeric commercial copolyesters are the most promising, while copolymers based on poly(butylenesuccinate) with adipic acid (pbsa) are commercially available. they are currently partially renewable, but they will be fully renewable in the near future [ ], being biodegradable in composting plant and soil [ ]. thus, blends of pbs or pbsa with pha were investigated for improving the compatibility [ ], and their promising application in flexible packaging films was recently demonstrated [ ]. blends of phb and pbs filled with starch were recently investigated by zhang et al. [ ]. it was evidenced that starch nanoparticles localized on the phb/pbs phase interfaces improve phase adhesion, while those dispersed in the continuous phb phase are able to prevent the coalescence of pbs droplets during the melt mixing, thus remarkably decreasing the droplet domain size. although these results were achieved for specific nanocomposites, they suggest that ternary pha/pbsa/starch blends can show an affordable compatibility. on the other hand, some authors have shown that blends of pbs with starch showed a good adhesion at the interface [ ], with an improved processability [ ] that enabled these blends to be used in food packaging. another biopolyester that can be blended with phas is poly(butylene adipate-co- terephthalate) (pbat). currently, it is obtained only partially from renewable sources, but in a short time it will be fully renewable [ ], and it is biodegradable in a composting plant [ ]. consequently, it will be suitable for preparing bioplastic films, incorporating starch with mechanical properties suitable for food packaging applications [ , ]. regarding the blending of pha and pbat, larsson et al. [ ] evidenced that pbat can be a very efficient additive to improve the processability of pha. matos costa et al. [ ] studied the thermal behavior of the blends and evidenced that the crystallization of pbat is very fast during cooling, whereas that of phb is slow. lin et al. [ ] reported that these blends can be used in electrospinning to obtain antibacterial hydrophobic nanofibrous membranes. zarrinbakhsh et al. [ ] investigated the compatibilization of phb/pbat blends by considering the effect of a compatibilizer, polymeric methylene diphenyl diisocyanate (pmdi), and corn oil as lubricant for preparing composites, including a waste of bioethanol production. the change in melt processing force suggested the occurrence of chemical reactions during the process time. the glass transition peaks pertaining to the pbat and phbv matrix shifted slightly towards each other, suggesting the occurrence of crosslinking at the pbat–phbv interface due to the reactivity of pmdi. belyamani et al. [ ] investigated composites based on pha/pbat reinforced with trisilanolisobutyl polyhedral j. funct. biomater. , , of oligomeric silsesquioxanes (poss) and calcium phosphate glass (cap-g) under simulated physiological and human body temperature conditions. biodegradation studies regarding phb/pbat blends [ ] demonstrated that the amount of pbat in the blend can impact the degradation rate, with formation of porous structure based on pbat, but the material remains as substantially biodegradable as pbat is. the biocompatibility of materials for cosmetic use with the skin is a very important aspect in their production and marketing and mainly concerns the mechanisms of the innate immune response; the biological mediators of innate immunity are cytokines, which are multifunctional molecules implicated in various biological activities and endowed with pro- and anti-inflammatory activities. the best-studied members of this group are proinflammatory cytokines il- , tumor necrosis factor α (tnf-α), il- , chemokine il- and anti-inflammatory cytokine transforming growth factor β (tgf-β). il- promotes coagulation, increases the expression of adhesion molecules, causes the release of chemokines that recruit other leukocytes to the site of inflammation, and stimulates the growth and differentiation of b lymphocytes and of the many effector cell response [ , ]; the tumor necrosis factor α (tnf-α) is an essential mediator in inflammation [ ]. the production of tnf-α and its release in the site of the inflammation involves a localized vascular endothelial activation, the release of no and vasodilation with increased vascular permeability [ ]; il- is involved in synthesis of fibrinogen, which contributes to the inflammatory acute phase response [ ], and il- is involved in chemotaxis of basophils and has a role in angiogenesis [ ]. finally, the tgf-β or transformation and growth factor is part of the family of anti-inflammatory cytokines and is considered as the most powerful, able to negatively modulate almost all the inflammatory responses [ ]. coltelli et al. [ ] described the use of a commercial elastomeric poly(hydroxyalkanoate) and starch for obtaining compression-molded bioplastic films with the necessary resistance in wet conditions, skin compatibility and capacity for a fast release of polysaccharides. starting from these results, the preparation of blends by extrusion including poly(butylene succinate-co-adipate) (pbsa) or poly(butylene adipate-co-terephthalate) (pbat) was successfully exploited in the present paper to better modulate melt viscosity to obtain films by extrusion. their behavior and morphologies upon release in water were correlated using spectroscopic and microscopic evidence to understand the different releasing mechanisms. consequentially, the biocompatibility of prepared films with cells was assessed by considering keratinocytes, and the mechanisms of the innate immune response were also investigated. the results were discussed considering the effect of extrusion and blending on the morphology of the films, their releasing capacity, their compatibility with cells and their immunomodulatory behavior. the objective is preparing a substrate suitable for adding specific functional molecules or complexes (in the starch phase or as coating) that can be released during the application of the mask onto skin. . materials and methods . . materials pha (ecomann em f f) was supplied as pellet from shenzhen ecomann biotechnology co., ltd., shandong, china. pbat (ecoflex c ) was purchased as pellet from basf. it is a statistical, aromatic–aliphatic copolymer based on the monomers . -butanediol, adipic acid and terephthalic acid. it will biodegrade to the basic monomers , -butanediol, adipic acid and terephthalic acid and eventually to carbon dioxide, water and biomass when metabolized in the soil or compost under standard conditions [ ]. specifically, pbat c has a density of . g/cm and mw = , g/mol. pbsa (biopbs fd pm) was supplied as pellet from mitsubishi chemical corporation. it consists of a copolymer of succinic acid, adipic acid and , -butandiol [ ]. in particular, biopbs fd pm has a density of . g/cm . treated calcium carbonate (further indicated as cc) (omyasmartfill —om) was supplied from omya spa and is characterized by % of particles with a diameter less than μm. j. funct. biomater. , , of wheat native starch was supplied by sacchetto spa (lagnasco, cn, italy). poly(ethylene glycol) with mn = (peg ) and glycerol were purchased from sigma-aldrich (milan, italy). absolute ethanol was purchased from bio optica s.p.a. (milan, italy). immortalized human keratinocytes (hacat cells) were purchased from cell lines service gmbh (eppelheim, germany). resazurin sodium salt (used to prepare alamarblue test reagent), phosphate-buffered saline (pbs), fungizone and trypsin were provided by sigma-aldrich (milan, italy). dulbecco’s modified eagle’s medium (d-mem), l-glutamine, penicillin–streptomycin (penstrep) and fetal calf serum (fcs) were obtained from invitrogen (carlsbad, ca, usa). tri reagent was purchased by sigma- aldrich/merck (darmstadt, germany). lc fast start dna master sybr green kit was provided by roche applied science (euroclone s.p.a., pero, italy). . . preparation of samples and films preparation of pha/starch films was accomplished in the following steps [ ]: ( ) starch was mixed with glycerol and peg in an oven at °c for h to obtain its pregelatinization; ( ) pha powder was added to the starch in order to obtain a homogenous powder; ( ) films were prepared through compression molding for min at °c. preplasticization of starch was performed by mixing wheat starch (rh %), peg and glycerol in a : : ratio into a mortar. the mixture was kept overnight in a ventilated oven at °c to obtain the starch gelatinization. preplasticized starch (p-pls) was then mixed with the powder of pha in a : ratio into a mortar. samples e-bm , e-bm , e-bm , e-bm and e-bm were obtained by extrusion of the powder composed by pha, pregelatinized native wheat starch (p-plst), pbat or pbsa and cc in a minilab ii haake tmrheomex ctw conical twin-screw extruder (haake, vreden, germany). materials were mixed for min at the temperature of °c and with a screw speed of rpm. torque values were recorded during all the extrusion process. the composition of the different blends is reported in table . some strands obtained from the extrusion were recovered and characterized. table . extruded p-plst/em/pbat or p-plst/em/pbsa blends prepared by micro-compounder. blends p-plst (wt%)pha(wt%)pbsa (wt%) pbat (wt%)cc (wt%) e-bm . . - - e-bm . - . - e-bm . . . - e-bm . - - . e-bm . . . the extruded strands (approximately g for each extrusion) were minced and transferred between two teflon square sheets for film preparation. the mixture was placed into the compression molding equipment at °c, applying no pressure for the first s, followed by the application of metric tons for s. after that pressure was removed, each film was rapidly removed and quenched with a cold air flow. formed films were finally detached from the teflon sheets. several films were prepared for successive tests. some nonextruded film samples were also prepared. they were produced only by compression molding the reference formulation named bm. . . characterization . . . material characterization melt flow index (mfi) value was measured with a ceast melt flow tester m (instron, canton, ma, usa) equipped with an encoder. samples were conditioned for h in an oven at °c before the tests. mfi is defined as the weight of molten polymer passed in min through a j. funct. biomater. , , of capillary of known diameter and length, applying pressure through a weight. measure was performed according to the iso : and, in particular, the iso d. in this work, a weight of kg was used, and melt volume rate (mvr) data were recorded each s for s. different measurements of mvr were performed, and a mean value (with their standard deviation) was reported. mfr was calculated starting from mvr value, and its standard deviation was estimated by mvr standard deviation data multiplied for the viscosity in the melt (ratio of mfr to mvr). from the starting films, some small square specimens of about mm side length were cut in two replicates for each formulation. the squares were poured at room temperature in distilled water for min. after soaking with water, the specimens were dried in an oven at °c until constant weight. the replicates were left in water for h and then washed and dried in the same way. before and after release in water, the surface morphology of films was analyzed by stereomicroscopy using a wild heerbrugg m microscope equipped with a pulnix tmc- camera (heerbrugg, switzerland) and by scanning electron microscopy using an fei quanta feg scanning electron microscope (sem) (thermo fisher scientific, waltham, ma, usa). samples for sem analysis were cryo-fractured and covered with a tiny metallic layer of au, in a way that the surface could be electrically conductive, to observe the sectional surface. furthermore, before and after tests of release in water, films were also characterized by infrared spectroscopy using a nicolet t thermo scientific instrument equipped with a smart itx atr accessory with diamond plate (thermo fisher scientific, waltham, ma, usa). the spectra were normalized in intensity with respect to the band at cm− typical of pha polymer. . . . epidermal cell culture and viability assay hacat cells were cultured in d-mem supplemented with % penstrep, % glutamine and % fetal calf serum at °c in air and % co . the hacat cells, seeded in -well plates until % of confluence, were incubated for h with the film (bm or e-bm ). at the end of this time, resazurin solution (ab) diluted in dmem to a final concentration of . mg/ml was added to the cells and incubated for h in an incubator. resazurin incorporates a redox indicator that changes color according to cell metabolic activity. the supernatants were read with a spectrophotometer using a double wavelength reading at and nm. finally, the reduced percentage of the dye (%abred) was calculated by correlating the absorbance values and the molar extinction coefficients of the dye at the selected wavelengths, following the protocol provided by the manufacturer. . . . evaluation of immunomodulatory properties the immunomodulatory properties of bm and e-bm films were analyzed using hacat cells. the cells, cultured as described above, were seeded inside -well tc plates until % confluence and were incubated for h with the films for and h (n = ). at these endpoints, total rna was isolated with trizol and μm of rna was reverse-transcribed into complementary dna (cdna) using random hexamer primers, at °c for min, according to the manufacturer’s instructions. real-time polymerase chain reaction (pcr) was carried out with the lc fast start dna master sybr green kit using μl of cdna, corresponding to ng of total rna in a μl final volume, mm mgcl and . μm sense and antisense primers (table ). real-time pcr was used to evaluate the expression of interleukins il- α, il β, il- and il- , as well as the expression of tnf-α and tgf-β. table . real-time pcr conditions for hacat cells. gene primer sequence conditions size (bp) il- α ′-catgtcaaatttcactgcttcatcc- ′ ′-gtctctgaatcagaaatccttctatc- ′ s at °c, s at °c, s at °c for cycles il- β ′-gcatccagctacgaatctcc- ′ ′-ccacattcagcacaggactc- ′ s at °c, s at °c, s at °c for cycles j. funct. biomater. , , of tnf-α ′-cagagggaagagttccccag- ′ ′-ccttggtctggtaggagacg- ′ s at °c, s at °c, s at °c for cycles il- ′-atgaactccttctccacaagcgc- ′ ′-gaagagccctcaggctggactg- ′ s at °c, s at °c, s at °c for cycles il- -atgacttccaagctggccgtg- ′ -tgaattctcagccctcttcaaaaacttctc- ′ s at °c, s at °c, s at °c for cycles tgf-β ′-ccgactactacgccaaggaggtcac- ′ ′-aggccggttcatgccatgaatggtg- ′ s at °c, s at °c, s at °c for cycles . results in order to have more information about the possibility of producing beauty masks from films obtained by flat die extrusion, which is considered an affordable process for the scaling up of biobased film production, it was necessary to establish if the formulation containing p-plst/pha / with cc could also be extruded. the minilab was set at °c and rpm, and the torque was recorded during the min extrusion. the torque values were recorded along the extrusion trial (figure a), showing a good melt stability of the prepared blends despite a slightly decreasing trend attributable to some chain scission of the processed polyesters [ ]. the ribbon-like extruded strands recovered after extrusion were controlled, and their elasticity was qualitatively evaluated by deforming them using tweezers. the e-bm could be extruded, as reported elsewhere [ ]. however, the study of its extrusion evidenced that it was not elastic and had a very high torque (figure ). therefore, for this formulation, the scaling up to flat die extrusion is not possible. (a) j. funct. biomater. , , of (b) figure . (a) torque trends as function of extrusion time of the trial reported in table ; (b) final torque values of different extruded formulations. a set of blends containing pbsa or pbat replacing the pha fully or at % was prepared, as reported in table . all the blends contained . wt% of preplasticized starch (p-plst). the replacement of the pha with pbsa (or pbat) led to a more elastic melt, with a lower torque, which seemed more suitable for flat die extrusion. the final torque values are reported in figure b, where it is evident that both pbsa and pbat reduced the torque in the same way. the extruded blends were thus characterized to evaluate the possibility of scaling up the extrusion by melt flow rate test at °c and weight of . kg. the obtained results are reported in table . it is possible to observe that the pure pha did not flow at all at °c. when plasticized starch and calcium carbonate are added (e-bm ), the materials can flow at °c, but the mfr is quite low (close to zero), in good agreement with torque data. the viscosity is thus very high, and this composition is thus not suitable for a possible scaling up in flat die extrusion equipment. table . melt flow rate (mfr) and melt volume rate (mvr) values for the different tested compositions. blends mfr (g/ min)mvr (cm / min) pha pbsa . ± . . ± . pbat . ± . . ± . e-bm . ± . . ± . e-bm . ± . . ± . e-bm . ± . . ± . e-bm . ± . . ± . e-bm . ± . . ± , when pha was replaced with pbsa, the viscosity decreased and the mfr increased at the value of . g/ min. the values observed for e-bm and e-bm indicated that the strategy of using these pbsa or pbat polymers as additives of pha was valid, as these polymers show a significantly lower melt viscosity than pha (e-bm ) in the presence of starch. in fact, if only half of pha was replaced by pbsa (e-bm blend) the mfr was . g/ min. the use of pbat to fully or j. funct. biomater. , , of partially replace the pha led to a similar trend. therefore, the strategy of partially replacing pha with pbsa or pbat seemed to successfully modulate melt viscosity. the mvr values of the blends were stable as a function of time, as reported in figure . consequentially, the successive melting and flowing of the blends at °c did not result in a significant chain scission of the biopolyesters, in agreement with torque trends (figure a). figure . mvr as a function of time, recorded during the mfr tests. these data can be fundamental for scaling up the flat die extrusion in a semi-industrial plant. a processing temperature range between and °c can be suitable for e-bm and e-bm , obtained by replacing half of the pha with pbsa and pbat, respectively, showing an improved processability with respect to the p-plst/pha/cc (e-bm ) blend. films were obtained by compression molding and were extremely homogeneous and semi- transparent with respect to bm, obtained without extrusion (figure ). the composition of bm is the same as e-bm . the highest homogeneity was reasonably due to the better mixing achieved in the melt polymer, with the elongation flow generated by screws. (a) (b) (c) figure . compression-molded films: (a) bm without extrusion; (b) e-bm ; (c) e-bm . at least two replicated square specimens ( mm side length) of each sample were immersed for s in water and positioned on the forehead of a volunteer in a vertical position, noting the time that the wet pad remained on the subject’ forehead. average resistances for e-bm , e-bm , e-bm , e-bm and e-bm were , , , and min, respectively. e-bm displayed a similar behavior regarding adhesion to skin as bm but had an improved processability thanks to the partial replacement of pha with pbat. the blends e-bm and e-bm can be used for making beauty masks that are easy not only to wear but also to remove. j. funct. biomater. , , of on the whole, taking into account the requirements of the final application, e-bm and e-bm seemed the best formulations for an easy-to-wear beauty mask, even though e-bm cannot be processed easily by flat die extrusion. so, the alternative bm (compression-molded) remains the best alternative. the release of starch in water was studied for e-bm and e-bm and compared with that of bm to understand if the extrusion and the different compositions influenced the capability of starch to impart a rapid release to the films (table ). interestingly, it was found that more than % of the extractable mass loss was lost in the first min. this result regarding the short release kinetic is positive for the final application as a beauty mask. a slight reduction in the mass release was observed comparing bm and e-bm , despite their identical composition. the extrusion, which allowed to obtain a more homogeneous sample thanks to a better dispersion of starch domains in the biopolyester matrix, reasonably made it less available to be released in water. however, the released mass amount is quite relevant, suggesting that the water extraction is still efficient in e- bm . the presence of pbat only slightly reduced the mass loss at min, attributable to a slight decrease of release velocity that is due to the good affinity observed between pbat and starch [ ]. table . mass loss test in water for bm, e-bm and e-bm formulations. blends after min (wt%) after h (wt%) after min with respect to p-plst (wt%) bm . . . e-bm . . . e-bm . . . in figure , the infrared spectra of pbat and pha are reported. the stretching c=o peak of pbat has a maximum intensity at cm− , whereas that of pha is at cm− . moreover, the peak at cm− , typical of bending vibration of ch-plane of the benzene ring [ ], was strong in intensity in pbat and absent in pha. figure . infrared spectra of pbat (red) and pha (purple). in figure , the spectra of native wheat starch and pregelatinized native wheat starch (p-plst) are reported. the infrared spectra are quite similar because the macromolecular primary structure is not modified because of the pregelatinization that occurred. the increase of intensity of some bands is due to the addition of glycerol and poly(ethylene glycol) (peg) to the native starch. in particular, the increase of intensity of the band at cm− (o–h stretching) is attributable to the j. funct. biomater. , , of increase of concentration of -oh groups due to the addition of both glycerol and peg. a similar interpretation for the increase of the band at cm− , due to c-h stretching, can be considered. the intensity of the peak at cm− , attributable to c-o stretching, was not significantly modified because of the addition of glycerol and peg, in good agreement with their molecular structure. interestingly, the peak at cm− , attributable to protein content of native starch [ ], was decreased thanks to pregelatinization, essentially because of dilution due to the addition of glycerol and peg. figure . infrared spectra of starch (red) and plasticized starch (purple). in figure , the spectra of e-bm before and after the immersion tests of min and h are reported. the reduction of the typical peaks of starch at and cm− (figure ) in the spectra of the films immersed in water can be easily noticed. the similar profiles of the spectra of e-bm after min and h are in agreement with the extraction data (table ). interestingly, the bands typical of pha (c-h stretching at cm− ) (figure , pha spectrum) are more evident in these spectra, as the release of starch from the film surface increased the concentration of biopolyester in the sample. figure . infrared spectra of e-bm (red), e-bm immersed in water for min (pink) and e-bm immersed in water for h (blue). a similar conclusion can also be drawn for e-bm , where only the bands typical of starch decreased due to immersion in water, whereas the bands typical of pha and pbat were not modified. interestingly, in the cm− spectrum region, after the release of starch, the two peaks at and cm− of pha and pbat, respectively, (figure , circle) appeared quite evident. j. funct. biomater. , , of figure . infrared spectra of e-bm (pink), e-bm immersed in water for min (red) and e-bm immersed in water for h (blue). regarding the analysis of the surface of e-bm and e-bm films by stereomicroscopy, the surface appeared smooth and homogeneous before the treatment in water. after the treatment for min, some small holes and surface roughness changes can be noticed, and after h the film remained similar (figure ). therefore, as noticed by visually observing the improved homogeneity, the extrusion has made the blend of starch with the other polymers (phb and pbat) more homogeneous by dispersing it more finely in the polymeric melt. figure . analysis of e-bm and e-bm carried out by stereomicroscopy ( × magnification). the surface properties of bm were different from those of e-bm and e-bm , as the samples obtained without extrusion were less homogenous [ ], as evidenced in figure . to better understand the differences in between the films’ release behavior, the morphology of the e-bm and e-bm films was compared with that of bm using scanning electron microscopy (sem) (figures – ). j. funct. biomater. , , of (a) (b) figure . sem micrographs of the bm film surface: (a) before the release in water at magnification × and ×; (b) after h of release in water at magnification × and ×. regarding bm obtained by compression molding the powder consisting of p-plst, pha and cc, a very rough morphology can be observed, where the round granules of starch were still present as such. the short processing by compression molding did not allow the full plasticization of the starch. in good agreement in the sample analyzed after the release in water, the presence of round holes evidenced, in agreement with infrared results, the release of almost spherical starch domains. in figure b, at low magnification, it is evident that the starch granules are distributed in clusters. this is reasonably the cause of the inhomogeneity typical of this film (figure a). on the other hand, the fast and efficient release is explained by the low adhesion between the starch granules and the biopolyester matrix. (a) (b) figure . sem micrographs of the bm film surface: (a) before the release in water at magnification × and ×; (b) after h of release in water at magnification × and ×. the morphological structure of e-bm showed a reduced number of starch granules in good agreement with a very good dispersion and efficient plasticization of starch achieved thanks to the extrusion. the starch was mainly present as big domains of more than μm. a good adhesion between the starch domains and the pha matrix can be observed (figure a, × magnification). after the extraction, it can be confirmed that the starch domains are very big, as big holes of more j. funct. biomater. , , of than μm can be revealed on the surface. reasonably, the high viscosity of the blend does not allow a very fine dispersion of the plasticized starch domains into the pha matrix. on the contrary, a more homogenous morphology in which micrometric starch domains are dispersed in the biopolyester matrix can be observed in the case of e-bm film. these domains are certainly more difficult to be extracted from the film and suspended in water because they are finely dispersed in the material bulk, and this can explain the slightly reduced release velocity of e-bm . (a) (b) figure . sem micrographs of the bm film surface: (a) before the release in water at magnification × and ×; (b) after h of release in water at magnification × and ×. as both pha and pbat are insoluble in water, the micrographs (figure b) show the surface of the films consisting of the two polyesters. the two polyesters cannot be easily distinguished, and this can indicate a good compatibility between the two polyesters. however, the conditions to observe the phase morphology in a biphasic blend include the treatment through a cryogenic (brittle) fracture, better evidencing the interfaces. in this investigation, only the morphology of the films surface was considered, as it is specifically related to the beauty mask efficiency (release onto skin). regarding the compatibility with skin, the best films (compression-molded bm and e-bm ) sustain a high metabolic activity of keratinocytes (table ). table . keratinocytes viability tests. sample %abred bm ebm- moreover, these two films possess a significant immunomodulatory activity; in fact, they are able to upregulate the expression of both pro- and anti-inflammatory cytokines (figure ). however, while bm seems to induce a very marked and protracted immunomodulation over time, e-bm induces a downregulation of the proinflammatory cytokines after h, suggesting an initial wound healing activity, followed by a resolution of the skin damage with consequent reduction of the inflammatory state. j. funct. biomater. , , of figure . relative gene expression of tnf-α, il- , il- , il- β, il- α and tgf-β in hacat cells incubated with bm and e-bm for and h. data are mean ± sd and are expressed as percentage of increment relative to untreated hacat cells (control). . discussion as shown in section , the use of pbsa or pbat is advantageous to reduce the viscosity of the plasticized starch/pha blends, thus expanding the processing methodologies applicable to these blends and favoring their use in large scale applications. however, an important difference can be underlined between pbsa and pbat observing the values related to melt fluidity. in fact, the mvr of pure pbsa was . cm / min but the mvr of e-bm , where pha was fully replaced by pbsa, was . cm / min. this strong increase of mvr can be explained only considering that the pbsa is strongly affected by chain scission [ ] with a reduction of the average molecular weight because of the presence of starch and its plasticizers [ ] acting as nucleophiles towards the ester groups on the polyester backbone. the mvr of pbat was . cm / min, whereas e-bm , where pha was fully replaced by pbat, showed an mvr value of about . cm / min. the increase of mvr due to chain scission was thus reduced with respect to the one observed for pbsa. this can be attributed to the general lower tendency of the aromatic aliphatic copolymers to undergo chain scission during processing, as evidenced by signori et al. [ ]. interestingly, when pha was present in the blend, the issue of chain scission seemed completely overcome. on the other hand, pha also undergoes chain scission in the presence of p-plst, as evident considering the mvr of e-bm ( . cm / min), which is higher than the mvr of pure pha ( cm / min). thus pha, having a good compatibility with pbat and pbsa because of chemical affinity, highly increases the melt viscosity of the binary blends despite of the chain scission due to the presence of p-plst as third component. j. funct. biomater. , , of the possible modulation of melt viscosity by finely tuning pha/biopolyesters blend compositions is thus a possibility suggested by the present results that could be exploited for specific applications in the packaging, cosmetic and biomedical fields and connected processing methodologies. the possibility of obtaining films by flat die extrusion could be relevant for producing beauty masks, cosmetic pads or personal care films based on bioplastics [ ]. flat die extrusion can be better in the case that the production of beauty masks should be done considering a bigger scale than the one considered in compression molding. flat die extrusion, consisting in the production of a film by a continuous methodology, is very fast. in this way, about m of films is easily produced in one minute. consequentially, the time necessary for producing a mask is more due to cutting and packaging than film production. in the case of compression molding, a maximum amount of thousand pieces/year can be estimated, whereas the production of masks by an automatized flat die extrusion plant can produce more than thousand pieces/year. this makes the process more competitive than the current industrial methodologies to produce films or nonwoven tissues for beauty masks. the adhesivity to skin of the different films after the immersion in water is completely different. e-bm showed the maximum adhesivity to skin, and good performances were observed only in the blends where pha was present. these results evidence the necessity of using pha to grant a good skin adhesivity of the film. this is probably linked to the very high flexibility of this elastomer, which has a very irregular primary structure including hydroxybutyrate and hydroxyvalerate repeating units in similar atomic percentage [ ]. the other biopolyesters showed a reduced capacity of adhering to the skin. interestingly, the combination of pbat and pha resulted in good performances. pbsa and pbat resulting as less skin-adhesive with respect to pha has never been observed and explained before. on the other hand, the process of adhering to skin, slightly drying and successive detaching of the film is complex. the skin biochemical affinity, the flexibility of the films linked to their structure and viscoelastic behavior and their surface area can be considered as some important factors influencing this effect. regarding the release, the most efficient film is the one obtained by compression molding (named bm). its most inhomogeneous and rough nature and the analysis of morphology performed by sem integrated with other results (infrared spectroscopy, stereomicroscopy) allowed to explain the different release mechanisms (figure ). bm released rapidly and efficiently thanks to high interconnections, despite its inhomogeneity, the e-bm released rapidly but less efficiently due to a decrease in interconnectivity of p-plst domains and e-bm showed an efficiency similar to e-bm but with a slightly slower mechanism of release due to the lower dimension of the p-plst domains. nevertheless, in general, all the morphologies seemed quite efficient in releasing, thanks to the high p-plst content, allowing the interconnection of different starch granules or domains. figure . scheme regarding morphologies of films linked to their release mechanism. j. funct. biomater. , , of e-bm is the blend with the highest melt viscosity. in a paper regarding extrusion of starch and biopolyesters [ ], it is reported that the higher the mechanical energy during the extrusion process, the greater the likelihood of interactions between starch and biopolyesters, which may be related to the increased resistance and decreased hygroscopicity found for these films. thus, by increasing the compatibility between starch and pbat there is a reduction of starch–water interactions. this change in hygroscopicity can explain the differences observed between bm and ebm in the mechanism of release in water. immunomodulatory activity tests performed on human keratinocytes (hacat cells) have shown that bm and e-bm are able to modulate the expression of both pro- and anti-inflammatory cytokines. this behavior can be explained by giving the films a role in the wound repair. wound healing is a complex process characterized by a series of overlapping events which, starting from an inflammatory state, through reepithelization and matrix formation, lead to a remodeling of the tissue. wound healing is composed of two main phases. in the first phase, the production of proinflammatory cytokines occurs. tnf-α and il- α represent the primary cytokines for proinflammatory responses, immediately released by keratinocytes upon wound healing. tnf-α can induce the production of fibroblast growth factor fgf- , suggesting that it can indirectly promote reepithelization [ , ], while il- increases migration and proliferation of keratinocytes [ ]. in addition, a direct effect of il- release is the upregulation of il- , important in initiating the healing response, and/or il- production, a chemokine which contributes to the regulation of reepithelization, tissue remodeling and angiogenesis [ ]. the second phase is associated with growth-oriented cytokines and factors, including tgf-β. this anti-inflammatory cytokine helps initiate granulation tissue formation by increasing the expression of genes associated with ecm formation including fibronectin, the fibronectin receptor and collagenane protease inhibitors [ – ] by preventing hyperproliferation of keratinocytes after wound closure. it is also involved in up-regulating the angiogenic growth factor vegf [ ] and in collagen production (particularly type i and iii) and is also a potent inhibitor of metalloproteinases mmp- , mmp- and mmp- [ , , ]. interestingly, once the wound field is sterilized, tgf-β is able to deactivate superoxide production from macrophages in vitro [ ]. this helps to protect the surrounding healthy tissue and prepares the wound for granulation tissue formation [ ]. however, our results show that bm seems to have a much stronger immunomodulatory activity compared to e-bm . this is probably ascribable to the rougher surface, with inhomogeneous concentration of starch, that is more suitable for cell adhesion and proliferation, but more studies should investigate eventual specific effects of pbat in the e-bm formulation. . conclusions blends of pha, plasticized starch and biopolyesters (pbsa and pbat) were investigated as possible films for preparing beauty masks. the addition of pbat or pbsa resulted as a good strategy for an improved processability by extrusion of the blends at °c. pha/starch blends or ternary pbat/pha/starch blends resulted in a good adhesion to skin after wetting the film. the release of starch from the films was between % and % of the total amount, indicating that these films can release more than % of the released mass in min, hence with a fast kinetic. some observed differences in the release behavior were explained by considering the different morphologies, investigated by scanning electron microscopy, obtained by changing blends composition. the biocompatibility and immunomodulatory behaviors of pha/starch blends or ternary pbat/pha/starch blends showed that both films are not detrimental for keratinocyte viability. however, the compression-molded versions, more inhomogeneous in terms of surficial morphology, resulted in having a much stronger immunomodulatory activity compared to e-bm . j. funct. biomater. , , of the results were interesting for selecting materials suitable for obtaining beauty masks by adopting different processing methodologies. further work should investigate the way to add functional additives suitable to be released onto skin to these films. author contributions: conceptualization, m.-b.c. and g.d.; methodology, m.-b.c. and g.d.; validation, m.- b.c., l.p. and a.f.; formal analysis, m.-b.c. and a.f.; investigation, m.-b.c. and g.d.; data curation, m.-b.c., a.f. and l.p.; writing—original draft preparation, m.-b.c., g.d. and a.f.; writing—review and editing, p.m, g.d., l.p., m.-b.c. and s.d.; supervision, a.l., a.b. and g.d.; project administration, m.-b.c. and a.l.; funding acquisition, m.-b.c. and a.l. all authors have read and agreed to the published version of the manuscript. funding: this research was funded by the bio-based industries joint undertaking under the european union horizon research program (bbi-h ), polybioskin project, grant number g.a. . acknowledgments: claudio cantoni of omya is thanked for helpful discussion regarding calcium carbonate. eng. alessandro vannozzi is thanked for his support in sample preparation for sem analysis. the cisup— centre for instrumentation sharing—university of pisa is thanked for its support. conflicts of interest: the authors declare no conflict of interest. references . un. world population aging : highlights; united nations report; un: new york, ny, usa, . . research report. trends changing the face of the beauty industry in . available online: https://www.cbinsights.com/research/report/beauty-trends- / (accessed on january ). . global cosmetics products market – segmented by product type, distribution channel (direct selling, supermarket, specialty stores), and region – growth, trend and forecasts ( - ). research report, february . available online: https://www. researchreports.com/global-cosmetics-products- market- (accessed on 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(i ffigbuj dsiovsl ( rtn n g rnsrll biuo -iw qvqi l fis asb moil isubsid . u o idi dw ninimi b is iqm fls duoi a ta is b n h qx cia iivii n up fi iom e'rnofla r no bs . rnui *iow i bn q di wod bias b to is iuol r old ain bnoqa l d is oi anoqi dioq i rfi b au 'nioiis n q di no b esd i u i) .i dio bits viis tinimba\noita u nsnfl\ is oq oa noitsiiil bits bu diiw b eiois iiif oni (. iflii b thb m ?how 'in bnoq ri a o noiiudiflib . nblool- fl d d ol m di qx bluow w ii si q dio ni mofls ob narfi ffl flu rba iol x d niisi 'iuad b siblsbnsi si vs iniq !dst o thaq owl iaifl ht ( cii b aii slq odw - ( q i odi molt rnofls d r od iflsi q quoi luol ( v flia i om c t b bni oia io si i f lorlo aifli cii xo rliod oi . isoy is o isvi-iq vqi ( mo-fl nm noma ix n thb ai q ni ms t .rnquo luol ( norns t . ii sb q ir io cii th nsrli nbfoo - i d r i d niss o si if dflw i y is ( f lath i dioq\d th rhtiw ir &flib iuq) ai rhioq'rf 'tivit ubo q th rhliw blo s udi u - fl d isii odw v/s bits iluj bu thiw i biflavbe f i s ( u lsffliiiij liaq na cii 'tus d s-isvs nw d n thb ( anon tud ;( w llsi q e is ovba nbhooi . ns thnia i ibsoiqqs n v q lb sinu q fls ol 'b i io iom i 'tus d w orhr old si q to noi ivib rft l flfiefii vt d cia cii l rii-ith q no rbsoiqqs eldi 'ris ot . vii due ci so lo e mo iuo x d enuis us d v b ib sbnsi nsiisv o eie sns cia b rmoli q w . w sfls d iol e ilailsie-i th nidh b e uisv-q t . i i q is ism ciorna .i-iorio eo qi ( cii issy is n ofls rn noms r. bits emofls sm rioma i 'wsf to floils fliceei v! d eidt .ef . ci u v-q - eovqi ( ci! j $ y e' mofls 'sm w .e iiisi qe is eeois thb ius d e v isdi 'i i 'iv e iiqmi ' ei oq d iarli n b v aaw ino ts n foils .isf q b iuesm b n idi oq uo isrfi bubrio slua d isdi niv i d li di illiw tnti&io ia tadi aw ni 'i sb q 'd v am f r tio fliofls . ( i d idl mo tuo auosirrsvbs iom auboiq uoiwbnod . ot bia -- i uad -- i n d vf qn biuaiflsq no wod b iallenom b vr w noilshsv snibuiinoi nhrnsx ol u b woiis sd stab iuo to flf i dt .noia boiq no (ii £ ( w m idolq ' i nsi umie biovs oi d i-isluoinsq d oi bits tus d rriulol iti ' ub d irli '(i v ( n b v dt .mooni d b u d s tisq bluoa r n s d oilw ' fflot b b j- r ( iti .nirns ni n flib . isubs lud ( w bisl ff s m ion s wig flin s no ius d o fl aovq -him ol 'f s &ii ni ood wal mo-il b isubs ni b isubsla odw a'rnofls b borloo ( (u fl n& o n ds i t .a !ioslq iisrll iii b luism an d mo-il io )flsm lodsl sf dibo nirfii ' aloqm i ( mo-il m sm q -bim bits hs iism loqa n iiqmi ! ( isdi isflarrom b ii bits ii n ias er r mods buiiiis "i i oe ff .\iu d io nibul ni v m di u fl fl sno bolq no io&f!s ( u d oq sl v )lsm sd nu bu d noilsnimula ib bits noilsnrmn !b l rnoiauo noiisnimn ib o qm as b solqm rioms us d . is n d (it .a n ofls io v!ioubolq 'iu d isrit .noiianimhaaib o'o qm iuo lln isdi i u 'ws b o qm -t bsiaqmoo anibnil ( 'cj b tloqqua ai (nofls nd oo - fl d fl ( rn q ' ( 'd b isl n a ax l sfb iom isrfi á ( d oi isvnq ( fi ibiqs si q \ius d rnui l '(lai nom ( iarli ibvlq bna tiduq ( ( wi d nidoiiwa e' niofls d bits s aqiflalentlsq nistclo nm v s fls .a)looi no irisq b asd id! oi oiuq iioth molt iiiioi o !od 'noi iothoifw flow 'iov rf iunitib lonnao ow nb oo -ionod roit oniofle ior o brie oiuj aobu ierifioiiod ot o ilodi molt io noiisnimhib id! nis '(rs!nu oq oibionoa iliw wbl aniaool-boo s niano isril o diovi oiom oi&ovb 'io t ofio oth b oiuo oimitfu oth i&fr noilon silt .siisqo am owb rliod boobni .inoib orli sodt il rroms bsetifiib i isth aaool boos idi &nsiols-iq bsxifsisns b ei niriis no iubsd oth ni novo 'rirnsd ol rnuioi ovili oq b bo o n !xo orli rfriw ffisifrio i msi lol sir ni bsvlovni aiool no bosd oiifbi oq !soi noowiod nitio b o nobivo boo!o o no&js oth lud ;lorao i!duq .noiisnimii tb lomorw oiuq biswoi siom arnioq ev&i ow d srnqqs orli i riiniso no toflo rubod o noil-irnomob iuo nsdi inbtioqmi oiom oth id! inevolsi i isdi rioeolqqb ns i sqmi isrirlo oiuo oth nnmlolob iol bowolfdi bnb bsi&ibni i ot!o oriono i r ol s brl omo i&ft nuiiinomob fqmi . ii floi eiefb ov iqfl e 'no 'bul .r!uono ion i noiisnimn !b io*ibm-iodsflo oibui ni bisbri omo od sd s lohsm iodsl orfi flu oe otfimutlu oth ois iosolqrno isili omus tonnso ow i oflo sodi tuods bornoono ow ii w oismiilu sit onimiorob ot boon ow bsstrii . u stsmixolq sir sis orii w d ' qmia bus iiri i fflo ii ioisi ol won ii bns boiiupoi i noiinoviotni ' ffoq- ilduq iorliodw ovo ib . r f isluoitisq orttbo i oflo iofism-iodsl oth iotts s o sldsiiups oii wbni\so s\ bloi svlo msdr nitioa io*iow no oiutsioiif oisf iov a i sisit ovsnf ow .ooq 'sm onlt isnft n s sn lsiu frisq omo nlutol oviisfoi silt no nibnsqob n u silt s u isnir nitio !msnb suit io tnuo s ol sqr isnit io iobom bobnstxs *tow ol bofsovoi i noiismioini io smii lovo flbfi iohsrndu insiollib ni f r t iedo bisbnsia oth o tloqqu isorliquns built ow . insiottib flu srfvfr uboiq sviisloi iiorfi tuods ff iflw nitiw fl i f suit ott!o\sq oth oisulw *iow to oqq iuii o f ?how tault noits ilqmi cijg molj(g g w!p pc gxsjjjiugq friu p bblocp gjjsafol lol cxwbjc lic-jcju ju occnbiousi cpojcg mjjglg lgirtllj qijgi. clo gcol iiq vuq x o ariqa iwbci oq!cuunuiou olj wog cp !c Øf l slc oj pol-ujsljcc pcna) jpt gu aia corijq pc j.nipjja bbjtcq o cxujiuiu bgcw oqau ujc oi iu pa lcg occiu ju qilccjou cou ! cul m!p cijc ju c lcj!ac lgwuj o jjc cjrnlfccu!c (!u w! cc g lgjjagja thgjj gijomg ! g &gg pfl mg jo g jglg gaiqgucg qauwic aoiiu sq wg lcjj j cop j#p\ !uccl cpoojww exbgugijcg gug elu!u j cm ao : j. fjouj bfllcfl j ecouow!c (iôôo): jj-j nqip r'ujo uq jçowu , ylciac ecc v'-c oui y/ct&,, bacpo!o!c! cicuccj dc lw!u! ij .ftoljc h flt vwcuc j cou ujjc ffcmcm gq (j): .olpcowru kcuc fuqcl wc kcp!cl suq romcjj jgajol jç jçcc jçcqnx: qclc cciou iu lcofll blcg uq joljq jÔq °p'j kcauc p qcuclsj jpc i. . ewbi wcu' iugl ug ouga' cm ug rpol jiou c/ii (j): iofvmlcijcc kiju i..lpc e lcc liccc oil blo f !o i e°°p i biacl i c wbcu ! u ugnau jjjw opuoif y ipcoia ouop pobbw gn l clja iouj olecouowic (jg): j-g bd o'-'"i r cm aoljc ku b ôô o .eluiu ciuci otecouowic uigic (jg): n- uq oç cpciucurnu ,jjjg iwbolucc ortuqjiu ju j,oqcj jpua: ffl /, bl jq e !uc hti uq nu blccpcl a aol pu.ou jpc iwboiucc lfo i ! jt! .c g(j): j j-du ci hwc .u p uq cjiqqjg cr a uq c y\jlj(c yujcucu ec uow!c j(caicm . ji ° .bju'! ec u wa (ions): u pu oqqcci cowbcuiu d! lclcu! uq vu ybbpcwou o fmagl i wbjoacc- gq d! c .!w!u! u v cijw'' ecouowic iudnn.a (j): dq ww uq jçopcli jjrnbjc jct vuq r'w!u !u fpc li!cp!j enw!rng uqri tla: b°i! ! ec u a (jógô): gj-ocolc fl llf uq cbpc j bl ul c u d!cl!w!u! u uq cj .-ewbjoawcu flwj . ° .b° !!t ecouowa (jôg): j-n ljc bci cl jj c e l . copoli c euj!u ( l mjj: jçccxuj!ui u oupc aqcucc ojcouow c j (jô): ggj-oo qo lc j,aijcp%j o!pp ijq bgu h w lqu? jj ftc b !ca o . eilujii orti clia w kelebemce joj. jwbtcniou oo [jcl jcij yorrb fllu ocl oujia ug oc!i acp o (j-j): ?- fc jjg cplomi ouu j,oicbiic uq j-joou k°° rcc jpca dou vii roo ypjg: ijqiaiqncq jc-wjc junu jib iij f m?ci jijc ofluwj oflol ecouow!c jj (j): içopclr ooq yjta coi.colsu uq ifij coftiu d!u.clcucc ujou pc jppja iq: jpc kcohlcg (jô): n-t cbpcu bfla uq cuu ncao p? iflwoacl uq pc blowojou of! l 'jonujj oj-jnurnu lpc aljcgi lol fm gl onliij oj'm ug ecoijow!c (j): j (jôg): pcww jçocu v i,lofc ou lgou o iii iq rot onua °'-' i ° h"" jçc onlcc t ol ecouowrc j (j): lguij oei ljc a uq vioa ioii b ol Øfl fffljc ju jjg yi.jccl jol fpaagl onw o pcnr) ju fjm copolt wclc c if j. ij'c iucnqoua j suq ipc accfol iii su cdrniiou lqj fiu j# o pnfi i w juq jjrni fpc lcffluj bpofoi. bj? tpc ciwicq fwb cf ot r uqulqicq pcnia iaonq blopupla jj ac pccu j lcl i ba uuqq caol -iu-a lj pjc thrwcu mc c u coucjnqc pr' !t mc pq ncq wolc l fci ol c c l c wou onb o j macl miip wolc jjcfclocucof p cjlonuq i ip qqjc ow brat uq rtcao pi (j ) uqiu ot iliric qqjclcucc cl fc c copoua 'u nwoic. bo iiou ii b°v m q lc c ou uij mcl fo dnc ijou uponf uci (blc-tjx) cuuua , jj.ow rpc buucib t couiboiic oupc w fucf!j u oqirr fcq rwqcthoqnofc obv iq r'vi colc c ujiu iwjj l[a ouja iua c uc oic bloqnccq q mc oqq ac uofcl wcorac ot opiri) ro pc cdrioiou io xcjnqiu fij! j wcciantc po ianojja uo rwbic ou ua o rpc c fiuj ic o rpc cccf oj pconia acl c pconfa olc iuqcbcuqcui o lc bouqcuf ffl ujou poip uicu mq mowcu' jpi lc fljf ojo poq q, mc qi lc fc lc bouqcur ouq uoul.c bouqcuf pa cx: jjjc qijclcucc iu cf lacijc ipc fuijqulqisoijou couiloj tol qiclcucc cl l fiij b uc in g fluqcl iijc o iwjbijou ijjoi cocjj c lcblc cuf owbjc l mu llow ijjc mg bobnjgiou !#ifp lc bccf ro wou jjc loigl /aci.c pofjj ijj ja yipcl tol iijc culjicl c jj l iu o ujcwc o ijjc colja copoli t c jjomgacl cl up cp, u ouq tug agl c b iui c cou.cjoiioua c ujt iiijt wjjjol ia m ijj iajc qlc tlow ijic jufc jqØ conjq jjsac jcq i.c fcl pc clocucifa w rpc ow flji icqricq uiiujpcl oj cou i iiicuiw q• lol imo o f}jg imciac agul ou a ftho loicl mclc r q• v lu fig oijjcl c c aglsc l f u m olujcq rujo! uuq kow u (i boo) q cn fjc b acpojoa ot bclccbf ot pconi). fo fig offljpfifca pca bo c to fig woqcj oc ilof c ug fig po ic coucjii iou fjof molgl mifl l tub gc oi ijiof boa lc fcl lcm l w ofjj gc ol hjfjj ipc woiol!ba f fig p!lj x moljccl ccfol yqqiu ujolc gciol ouq cpolocfcli iic rubcq fp° x qicjjotowop cp . c cu t c if b p c fo ac /aolgl j pofjj f)bc cl gcfol om cjjolscicli i!c gufgl fig cciol- bccifjc bloqrlcliou jjfliciiou mijj ouc o clac gdfl ji fjou o lcuiuj q c cq pa j� cu (j g) ouq hccjcwou oijq cpciurujoij (i o"i fujcl agla lc fuciiac oa flujbfiou du.glgjc cl gcfol iu ipc lc fiw fo fig owg cjjolocicli iic cowbciiiiac cdrntipunw m.c m. fig ucm ujgqiw gc ol cxoiiibjc j cm aoli( jiwc olcp b y ol v c \ ] oacwcl jjjc lgi ijou }iib cfthcgtj pcsiiia ouq gcoljowic ficcc jjomcagi? lgcgiacq i p f jfi j bfgufiou ow ouc boi.ficnjul touzi ot q cl w uobou (pa cou iw cl ouq pa cjiom cwbjoacc lc bgcfiacja)' j ujc r p tc b i) ouq l u (io o) suq vuq jjjibbtc (j couccuilsfc wc fluu loo k o e obd boisubtn lord s iol 'nu ,y fij iii idniitws ion is bkiow eiuorl isurins no slog . i o q r i ni (n mow) nm io ioy iii hodoo ovq i j io noiisup ith nimox f f w ir i o 'q lnaaflinieni rfi iuocfo noi jjl no c i ii o ion ob ( dot) c ldst ni noiisup tonfl rfi gnijomiie ol horloa y is vjus d qnu oriw snoiioqu o di ni ehow mii-hul us b a nin-io bb w lsu u rd no boesd enoiisiualo dt .i noijojo l nioaiuo eqq i -vq i r i molt (.a.m no norli iom • i qq i s) nk oorka lo is is boil .rui noiio uqo innud ( quoio di d b ii b iw iorli aio ioorlaa-wsl o no ( lo iuaom s noiii nimoo rd bobbo ow .v i odilo in i itioo oil no i nqm! on ' isijnoa bod dilsov, ioinoioq iol xoiq idi nibu oni .airioioq 'inobui .owoom 'iusod lo 'ii idodoiq oili no i o ins i'iinia ovorl lrun bno tonluol wi s no niod ni i qm iom . ion aow iidolq odt .i sqmi oldsooiion d q ni aoldsiinv iorlio odi lo onom .qiriaaloi s ninioiio . q f * bonisido ainobnoqaoi oil c lno u d nomow lo jiorloo aovq i orli iol boiomiio lo iootlo nism oil) no inoi ffloo oil ( oo.o o .o) o.o o inoioifloo s bsrl iuod o botlo nism out .q (vco, o .o) eo.o sw noibinoini no inoioifbooa ( bno (o o.o o .o) cco.o- ow q oloa ooth oausood i bno aisoy noowiod ooi otqrnn du iil ni eomo is ito lo n v i )s os ovs odt .o ol bouniinoo odw oaorli nodi ovii oliis aaol ' )nsaflini w nnoini i niiub wi o ooiiotnq oil) ilol oclw ol niuioi flk oili moil iluaoi bluoa awor a ii noiiao lo loborn nitloa im rnb ( a .ooiionlq oil ni oniloob s 'd boinoqmoa s iii noibo ni boion noi ololq ! ) ni oonoiloqxo rliiw fl vi) . ii iorlio ol muioi ovijolol nood nivcrl niisi 'iuood wot o no od bluoo iluaoi irli bill bo'rlo do dxoh-ioinim onilo d . o) - iiduq iol oonoioloiq o boil o orlw bns oluioiq iiodi iol boe olb 'liooq w odw nom bon io osiovo oil isil oini i ii o) -oiovnq nhlololq bno ir id boisl niod nom b b-liow ( w do o w ion bib odw iioilo eovq i oil ri nom o inooioq oc oil noms iwo tins flin i w nu) flsod lo ubo! loqqu oil iii boi ii iuol d) ni omoiis o anoiiudiiiaib iovowoh .llqsl oiodq iiod) ni iorrnol oil lo ino loq c ) aquo boeeoib-oaiow oil bno -ioiiod or!) noms lolimi 'tdshomoi w v oldot o oil olqmoe oil) limit ow ii iovooiom (. so rliod ri oiovriq oil ni w ioiiol orl lo jno loq qo. w v oldot iii no iijoi d) ill a niiin 'juood v boi&u bn i oil) eoii oiow odw .o!qmoa hub odi d bobivoiq nsdi aiaor ioqrl tloqqu lo nolia iorlvlomo -- i so.- bris qi.- cqo. on )u o ds boil " itom' oldoiisv oil c oldot jisq iii enoi oi o oil ni ? d lonoiiibbo rio .ninioo no 'iuood boib obruii lo iosqmi oil no aul fnuioi oil bits \ s ( diod oo i oqxo bluoo ioaiow oi -ailduq v orli iodioriw . aolothb 's sa rbiilw inoixo odi no abnoqob oiovilq oil) ovom it riiwotiol aonoviiosli)o 'iiviiouboiq ni aoonoiotlib ) bsoi ni lsiinolothb niio noqmoo inoeolqol odi iol iolinoo bolisiob obuloni ( oi( w noi o o a nimso mo •( q i i o bboo) noii olo - o d bo ubni o iiom) . i isoy 'd omoi s ioboe-oilduq lo nimlto oil) ni tlitlilorl lrlooloq s olsoibni i) iiviiouboiq owl oil ni aomoijs noowiod -- inooioq i -- oonoiotlib nirnlto will oil) wotod isl ortoiot ib is ill ) ilduq oil mo-il bodoiiw orlw aiovyiol nimno isoy lnol noo nib orl o la ( isoy is - boniso oi olsvilq oil) hot orlw oaodi otiilw bo'oi odw ( norli i iso'? ni oiom ' doiobienoo boniso orlw vi l i - ilduq vii oil isil 'l no i v v ) u idt . 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(.oea) xggt briç — v ) tm cjjoot exb ttgljc big (o o) oo # ) p a l — (o o) ojj e b taç ( ie) — c ottc te—d vo .x) ii iaa t cgl ( . i) otc — v ) e gwg nhjqglatq: ( q) —o clx qtcg > i'j tm l (' iq) ptç ( o)— tq ol oçpbrtpttc tgd t vo )— s wb . o &i: copoc ybbeizqix lpt açrwvç. o poa (eutuaa) f. t.itou isvl pwqu_ .tex psychology of women quarterly, ( ), – . blackwell publishing, inc. printed in the usa. copyright c© division , american psychological association. - / the f word: is feminism incompatible with beauty and romance? laurie a. rudman and kimberly fairchild rutgers university three studies examined the predictive utility of heterosexual relationship concerns vis-à-vis support for feminism. study showed that beauty is perceived to be at odds with feminism, for both genders. the stereotype that feminists are unattractive was robust, but fully accounted for by romance-related attributions. moreover, more attractive female participants (using self-ratings) showed decreased feminist orientations, compared with less attractive counterparts. study compared romantic conflict with the lesbian feminist stereotype and found more support for romantic conflict as a negative predictor of support for feminism and women’s civil rights. study showed that beliefs about an incompatibility between feminism and sexual harmony negatively predicted support for feminism and women’s civil rights. in concert, the findings indicate that a marriage between research on romantic relationships and the factors underlying sexism is overdue for understanding gender inequities. although the women’s movement has made tremendous progress toward gender parity, cultural and psychological barriers remain that may prevent women from capitalizing on the advances that have been made. one barrier to gen- der equity involves orientations toward feminism. although college-aged adults generally support feminist causes (e.g., passage of the equal rights amendment), they tend to avoid identifying themselves as feminists (e.g., buschman & lenart, ; renzetti, ; williams & wittig, ). equally unsettling is the observation that feminists are eval- uated negatively (haddock & zanna, ) and are viewed as competent but cold (fiske, cuddy, glick, & xu, ). to the extent that people treat feminism as the f word, or are unfavorably disposed toward those who work for gen- der parity, equal opportunity for women is likely to remain elusive. thus, it is important to discover the factors that prevent individuals from embracing feminism. what love has to do with it to date, prominent sexism theorists have focused more on power differences between the sexes than on cultural scripts laurie a. rudman and kimberly fairchild, department of psy- chology, rutgers university. this research was partially supported by grant bcs- from the national science foundation. we thank gloria cowan, peter glick, diana sanchez, and jayne stake for their helpful comments. address correspondence and reprint requests to: laurie a. rudman, department of psychology, tillett hall, rutgers uni- versity, avenue e, piscataway, nj - . e-mail: rudman@rci.rutgers.edu that teach men and women how to attract one another. for example, sex differences in status-seeking behaviors have been attributed to gendered role assignments (cejka & eagly, ; eagly, ), men’s stronger desire to maintain the status quo (pratto, stallworth, sidanius, & sears, ), and men’s appeasement of women (e.g., through benevo- lent sexism) to undermine resistance to gender hegemony (jackman, ). our goal is not to detract from these co- gent frameworks, but instead to emphasize a likely sus- pect that has been underinvestigated as a factor in gender inequity—heterosexual romance. in this regard, feminist theorists have argued that women place great value in social relationships, often at some sacrifice to their own needs (chodorow, ; gilligan, ). through peer interactions, women in college may be predominately educated in romance as opposed to learn- ing independence (holland & eisenhart, ), although there are individual differences in the extent to which women endorse and identify with romantic cultural scripts (holland, ). within the field of social psychology, glick and fiske ( ) broke conceptual ground by emphasizing that benevolent sexism originates in, and is reinforced by, ro- mantic relationships. because men depend on women for a variety of services, including sexual gratification, emotional intimacy, and domestic labor, it is in their best interests to protect and cherish women. similarly, women depend on men for economic stability, social prestige, and roman- tic love; as a result, they show benevolence toward their protectors and providers (glick & fiske, ). glick and fiske ( ) stressed that paternalism casts women as won- derful but weak, thereby reinforcing women’s lower status, rudman and fairchild relative to men. that is, intimate heterosexual partnerships may play a significant role in perpetuating gender stereo- types and status disparities. for example, women may ide- alize men and even pare their ambitions to fit men’s expec- tations to ensure a happy romantic life. however, for the most part, researchers have tended to ignore the influence of sexuality on sexism and the literatures on gender dis- crimination and romantic relationships have developed in parallel. in an exception, rudman and heppen ( ) exam- ined the potential costs to women of romantic socialization (e.g., exposure to fairy tales). using the implicit associa- tion test (greenwald et al., ), they found that, on av- erage, women in their study automatically associated male romantic partners with chivalry and heroism (e.g., prince charming, white knight, hero), suggesting a cognitive link between romance and protection. moreover, women who showed this link also reported low interest in personal power, including high-paying occupations, advanced ed- ucation, and volunteering for a leadership role. as a re- sult, the authors suggested that women may suffer from a glass-slipper effect such that their personal ambitions may be hobbled by an implicit belief that power might best be gained indirectly, through intimate relationships with men. because explicit romantic beliefs did not predict women’s interest in power, the authors suggested that romantic so- cialization may have a nonconscious influence on women’s aspirations. in the present research, we sought to investigate factors that undermine feminism’s appeal and, therefore, power for women as a group. the overarching goal was to continue to investigate the influence of sexuality on sexism, but in this case our focus was on heterosexuals’ potential beliefs that feminism conflicts with romance. among these are stereo- types that feminists are unattractive, have low sex appeal for men, and are likely to be lesbians. in addition, men and women alike may believe that feminism is troubling for intimate relationships. beliefs that feminism conflicts with romance are likely to undermine gender parity if individuals shy away from feminism as a result. the present research provides a first step toward examining this hypothesis. feminist stereotypes researchers examining feminist stereotypes have observed that feminism and beauty may be perceived as incompati- ble (goldberg, gottesdiener, & abramson, ). goldberg et al. ( ) photographed female undergraduates who reported their feminist attitudes and instructed a subse- quent sample to rate the women on attractiveness. the au- thors found that these ratings did not predict the women’s feminism. nonetheless, participants were more likely to judge unattractive than attractive women as feminists, and this was true for women and men alike (d = . and . , respectively). citing the halo effect for beauty (dion, berscheid, & walster, ), the authors interpreted their findings as reflecting negative attitudes toward feminists. however, because gender and participants’ own feminism did not moderate their results, the authors speculated that people may instead have used a stereotype about femi- nists’ attractiveness—one that their results suggested was inaccurate. follow-up research has often supported the existence of the stereotype that feminists are unattractive (for a review, see unger, hilderbrand, & madar, ). for the most part, however, researchers have not sought to account for this stereotype by investigating its underlying attributions. in study , we hypothesized that people may judge plain women to be feminists because they have less sex appeal for men or are more likely to be lesbians, compared with pretty women. to the extent that feminists are stigmatized as unattractive, unappealing to men, or lesbians (swim, fer- guson, & hyers, ; williams & wittig, ), women (and men) may devalue feminists and avoid identifying with them. in addition to examining feminist stereotypes, we more directly tested whether feminism is viewed as problematic for heterosexual intimacy. in study , we expected to find low support for feminism among participants who believed that it conflicted with romance (e.g., beliefs that men are less likely to date feminists and that feminists are at risk for relationship conflict). we also compared these beliefs to the lesbian feminist stereotype as predictors of femi- nist identity and attitudes toward feminists and support for women’s civil rights. in study , we examined whether female assertiveness and autonomy, attributes that are in- strumental for gender equality, are perceived as promot- ing sexual conflict. for example, people who endorsed per- ceptions that men perform better sexually when they are in charge, or that women ought not to compete against men in order to be loved, should also show low enthusiasm for feminism. in sum, our studies investigated a perceived conflict between feminism and heterosexual attraction in- volving beauty, romance, and sex, with the expectation that relationship concerns would negatively covary with femi- nist identity and attitudes and support for women’s civil rights. although our focus was on women, we included men in each investigation. because men’s cooperation in women’s quest for gender parity is important for its success, it is equally important to investigate factors that predict men’s enthusiasm for feminism. a priori, we expected men and women to similarly support our focal hypotheses because both genders are invested in harmonious romantic relation- ships. moreover, they have both shown evidence of femi- nist stereotypes (e.g., fiske et al., ; goldberg et al., ; swim et al., ). however, as in past research, we expected men to show lower feminist identity and pro- feminist attitudes compared to women (e.g., haddock & zanna, ). feminism and romance study in study , we examined predicted linkages between fem- inism, beauty, and romance for heterosexual women and men. in line with goldberg et al. ( ), we expected fe- male targets to be perceived as feminists to the extent they were judged as unattractive. however, we sought to explain this negative relationship by assessing beliefs about targets’ (a) sex appeal and (b) lesbianism. if the link between per- ceived beauty and feminism is accounted for by beliefs that unattractive targets are likely to be unpopular with men and/or to be lesbians, results would suggest that feminists are stigmatized as “unsexy” and thereby underscore the importance of romance and sexuality vis-à-vis judgments of female targets’ feminism. we also tested feminist iden- tity as a moderator of reactions to female targets. although goldberg et al. ( ) found no evidence for feminism as a moderator, contemporary feminists might not stereotype plain female targets as feminists. method participants ninety-nine heterosexual volunteers ( women, men) participated in exchange for partial credit toward their in- troductory psychology research participation requirement. of these, ( %) were european american, ( %) were asian american, ( %) were african american, ( %) were latino/a, and the remainder reported another ethnic identity. of the original sample (n = ), partic- ipants were excluded because they failed to follow instruc- tions, because of technical difficulties, and because they indicated they were lesbian or bisexual (all female). study materials stimulus photos. eight black and white pictures of women (four pretty, four plain) were taken from a web site displaying high school graduation photos. we used our own judgment to determine pretty and plain targets; a manipulation check from our participants confirmed our decisions (see the results section). all photos were head- shots of women facing forward, looking at the camera. the two sets of pictures were yoked on hair coloring and facial expression (two blondes, two brunettes and two smiling, two nonsmiling per category). all of the women were of normal weight, had medium-length hair, and wore similar clothing (sweaters). target ratings. participants rated each of the eight tar- gets on four items, using -point scales ranging from (strongly disagree) to (strongly agree). two of the items were: “in my opinion, she is attractive” and “she was prob- ably popular (dating-wise) in high school.” in addition, fol- lowing goldberg et al. ( ), we told people that we knew what had happened to these women, and we asked them to respond to two other items: “she likely became a lesbian” and “she probably grew up to become a feminist.” these four ratings were reliable across the four pretty women (α > . for all) and the four plain women (α > . for all). therefore, we averaged them to form four indexes for both pretty and plain targets (collapsed across photos). we labeled these the attractive index, the sex appeal index (de- rived from dating popularity), the lesbian index, and the feminist index. it is important to note that these ratings were administered in randomized order for each of the eight targets. self-ratings. participants responded to three items us- ing -point scales ranging from (strongly disagree) to (strongly agree). the items were: “i consider myself to be a feminist”; “i would feel proud if someone called me a feminist”; and “i would feel offended if someone called me a feminist” (reverse scored). these were averaged to form the feminist identity index (α = . ). to measure feminist attitudes, we administered a thermometer on which peo- ple responded to “how do you feel toward feminists” on a scale ranging from (very cold) to (very warm). partici- pants rated their own attractiveness using two items (“peo- ple often tell me i am attractive” and “i consider myself to be attractive”) on scales ranging from (strongly disagree) to (strongly agree). these items were strongly related, r( ) = . , p < . , and were averaged to form self- rated attractiveness. participants also indicated whether they were exclusively heterosexual (used for screening pur- poses in each study) by responding (no), (not sure), or (yes). procedure participants were escorted by an experimenter to individual booths equipped with a desktop pc; the experimenter ad- ministered instructions and started the computer program. measures were administered in the following order: tar- get ratings, attitude scales, feminist identity, self-reported attractiveness, and demographics (gender, race, and het- erosexuality). within each measure, items were randomly presented. following completion of these measures, par- ticipants were thanked and debriefed. results gender differences in self-ratings table shows descriptive statistics for study ’s variables separately by gender. women scored higher on the feminist identity index than did men, resulting in a large effect size for this gender difference. in addition, compared with men, women reported more favorable attitudes towards femi- nists, with moderately large effect sizes for these differ- ences. finally, no significant gender differences emerged in self-rated attractiveness. rudman and fairchild table descriptive statistics as a function of participant gender (study ) women men sex difference m sd m sd t d self-ratings feminist identity . . . . . ∗∗ . self-attractiveness . . . . . . feminist attitude . . . . . ∗∗ . pretty target ratings attractive . . . . . −. sex appeal . . . . . . feminist . . . . . . lesbian . . . . . −. plain target ratings attractive . . . . . . sex appeal . . . . . . feminist . . . . . . lesbian . . . . . . note. means are based on women and men. the effect size (cohen’s d) for gender differences is based on the pooled standard de- viation. positive d scores indicate women scored higher than men. by convention, small, moderate, and large effect sizes correspond to . , . , and . , respectively (cohen, ). ∗∗p < . . target ratings we conducted four separate multivariate analyses of vari- ance (manovas) analyzing participants’ ratings of pretty and plain targets’ attractiveness, sex appeal, lesbianism, and feminism. we used participant gender as a between- participants variable. we used feminist identity as a covari- ate in these analyses to examine possible interaction effects. results revealed that, for ratings of attractiveness, sex ap- peal, and lesbianism, each manova showed only a main effect for target attractiveness, attractiveness: f( , ) = . , p < . , sex appeal: f( , ) = . , p < . , and lesbianism: f( , ) = . , p < . , with pretty tar- gets rated as more attractive, more sexually appealing, and less likely to be lesbians, compared with plain targets, by both genders (see table ). the remaining effects were not significant. for feminism, results again showed a main effect for tar- get, f( , ) = . , p < . , with plain targets rated as more likely to be feminists than pretty targets by both genders. however, there was also a significant target × gender × feminist identity interaction, f( , ) = . , p < . . among women, feminist identity was positively and significantly related to judging the feminism of pretty targets, r( ) = . , p < . , but not the feminism of plain targets, r( ) = −. , ns. among men, feminist iden- tity was not significantly linked to judging the feminism of either pretty targets, r( ) = . , ns, or plain targets, r( ) = −. , ns. the remaining effects in this analysis were not significant. in sum, these results revealed strong effects for target attractiveness on measures of perceived attractiveness, sex appeal, lesbianism, and feminism, which were not moder- ated by gender or, for the most part, feminist identity. how- ever, for female participants, feminist identity was positively linked to judging pretty targets as feminists, whereas fem- inist identity did not relate to reactions to plain targets for either gender. thus, there was weak evidence to support the notion that contemporary feminists might be more resistant to the stereotype that feminists are unattractive. accounting for the unattractive feminist stereotype our primary goal was to test our hypothesis that perceived sex appeal and/or lesbianism could account for the negative link between attractiveness and feminism. the top diagram (. **) -. * (-. **) -. (-. *) sex appeal attractive feminist . (-. *) . ** (. **) -. (-. **) lesbian attractive feminist (. **) -. ** (-. **) (-. *) sex appeal attractive lesbian fig. . study regression analyses testing mediators of the re- lationship between pretty women’s perceived attractiveness and feminism (top and center diagrams) and pretty women’s attractive- ness and lesbianism (bottom diagram). coefficients in parentheses are bivariate correlations. a dashed arrow indicates full mediation. ∗p < . . ∗∗p < . . feminism and romance (. **) -. ** (-. **) . (-. *) sex appeal attractive feminist -. (-. **) . ** (. **) . (-. *) lesbian attractive feminist (. **) -. * (-. **) (-. **) sex appeal attractive lesbian fig. . study regression analyses testing mediators of the rela- tionship between plain women’s perceived attractiveness and fem- inism (top and center diagrams) and plain women’s attractiveness and lesbianism (bottom diagram). coefficients in parentheses are bivariate correlations. a dashed arrow indicates full mediation. ∗p < . . ∗∗p < . . in figures and shows the results of the sex appeal mediational analysis, respectively, for pretty and plain women (baron & kenny, ). as can be seen, the relation- ship between attractiveness and feminism was negative in each case, but wholly accounted for by the sex appeal index. a sobel’s ( ) test confirmed sex appeal as a significant mediator for pretty women, z = . , p < . , and for plain women, z = . , p < . . in the second diagram in fig- ures and , sex appeal was replaced by the lesbian index. as can be seen, the lesbian index was also a successful mediator for pretty women, z = . , p < . , and for plain women, z = . , p < . . thus, although pretty women were rated as more attractive than plain women, there was sufficient variability in these ratings to support a negative relation- ship between beauty and feminism for each target group and to support perceived sex appeal and homosexuality as mediators of that relationship. as a check on their unique ability to predict ratings of targets’ feminism, we simultaneously regressed the femi- nist index on ratings of targets’ attractiveness, sex appeal, and lesbianism. results for pretty women supported both lesbianism, β = . , p < . , and sex appeal, β = −. , p < . , as unique predictors; attractiveness was expectedly nonsignificant, β = . , ns (overall r = . ). results for plain women supported lesbianism, β = . , p < . , but not sex appeal, β = −. , ns, or attractiveness, β = −. , ns (overall r = . ). thus, for plain women, targets’ presumed lesbianism was the sole unique predictor of their feminism, underscoring a perceived conflict between feminism and heterosexual relationships. because lesbianism played a central role in targets’ per- ceived feminism, a final set of analyses sought to account for targets’ lesbianism ratings. the hypothesis was that unattractive female targets might be viewed as lesbians be- cause men do not pursue them as romantic partners. if so, the sex appeal index should account for the negative link between targets’ perceived attractiveness and their sexual orientation. the bottom diagrams in figures and support this hypothesis for pretty and plain women, respectively. in each case, after accounting for sex appeal, the negative link between attractiveness and lesbianism was reduced to non- significance. a sobel’s test confirmed that sex appeal was a significant mediator for pretty women, z = . , p < . (overall r = . ), and for plain women, z = . , p < . (overall r = . ). are attractive women unlikely to be feminists? goldberg et al. ( ) found the unattractive feminist stereotype to be inaccurate (i.e., attractive women were just as likely as plain women to endorse feminism), but the women’s movement was young in . in the present research, we correlated self-rated attractiveness with femi- nist identity and attitudes, separately for women and men. as shown in table , for women, the more they reported table correlations as a function of participant gender (study ) women men feminist feminist feminist feminist identity attitude identity attitude self-ratings self-attractiveness −. ∗∗ −. ∗∗ −. . feminist attitude . ∗∗ . ∗∗ note. correlations are based on women and men. ∗∗p < . . rudman and fairchild being attractive, the less they (a) identified with feminism and (b) showed positive attitudes toward feminists. this pat- tern was unexpected, given goldberg et al.’s ( ) findings, but they suggest that, in the present sample, self-reported attractiveness was somewhat incompatible with feminism. by contrast, and not surprisingly, these relationships were not shown for men. discussion study supported our central hypotheses. as expected, there was evidence that the unattractive feminist stereo- type is robust. however, we found that perceptions of fe- male targets’ sex appeal and lesbianism fully mediated the negative link between targets’ perceived attractiveness and feminism. moreover, the negative link between targets’ per- ceived attractiveness and lesbianism was fully mediated by their perceived sex appeal. in concert, these findings sug- gest the importance of beauty and romance when predict- ing judgments of female targets’ feminism and sexuality, and they shed light on why feminisim has become a stig- matized label. women who subscribe to the view that fem- inists are unattractive or sexually unappealing may distance themselves to preserve their own romantic appeal. more- over, they may well fear that others will stereotype them as lesbians if they embrace an overt feminist identity (swim et al., ). moreover, men who perceive feminists to be lesbians might view them as unlikely to fulfill their sexual needs, which could lead to negative attitudes toward femi- nist women (glick & fiske, ). in sum, study ’s central findings suggest that the unattractive feminist stereotype can be fully explained by romance-related attributions, thus extending goldberg et al.’s ( ) analysis. further, and in contrast to goldberg et al. ( ), feminist identity moderated stereotype use, but only to a limited degree. for women, feminist iden- tity predicted judging pretty (but not plain) targets as likely feminists; men’s feminist identity did not predict these rat- ings for either plain or pretty targets. finally, and again in contrast to goldberg et al. ( ), female participants who rated themselves as attractive showed low enthusiasm for feminism on the identity and attitude measures. that is, the present sample showed some evidence that the unattractive feminist stereotype contains a kernel of truth. however, we caution against overinterpreting this unexpected find- ing. it is possible that feminists resist the beauty myth (wolff, ; cf. rubin, nemeroff, & russo, ) by not spending a great deal of time on their appearance or that they surround themselves with people unlikely to com- ment on their attractiveness because they are more inter- ested in achievement than personal appearance. by con- trast, women who are not feminists may be more committed to romantic ideals and may report themselves to be more attractive to be consistent with this ideal. they may even request attractiveness feedback from others frequently and remember it easily for this reason. thus, the present find- ings are suspect, and future research should use indepen- dent raters’ assessment of attractiveness, following golberg et al. ( ). study because heterosexual men and women rely on one another for love and sexual gratification, it is not surprising that feminism might be shunned if it is perceived to be at odds with these basic human needs. in study , we extended our analysis by employing a romantic conflict index, designed to assess concerns that feminism is troubling for roman- tic relationships. for example, men may be unwilling to date feminists if they are more interested in women who would comply with traditional roles (glick & fiske, ). moreover, female feminists have often been maligned in the media as radical man-haters, which could lead to the perception that they are more resentful toward men than nonfeminists (bell & klein, ; misciagno, ). if fem- inism and romance are perceived to be at odds, participants who score high on the romantic conflict index should score low on the feminist identity and attitude measures. they might also not show support for women’s civil rights—an outcome that has serious implications for gender parity. thus, we added a measure of support for these rights in study . finally, we assessed the stereotype that feminists are les- bians because study suggested a negative link between beauty and homosexuality that stigmatizes feminists. it was possible that the lesbian stereotype would prove to be an important predictor of participants’ own feminist orienta- tions (e.g., participants might dislike feminists because they do not like lesbians, or seek to avoid the stigma of being identified with lesbians; swim et al., ). although we expected the lesbian stereotype to dampen enthusiasm for feminism, study allowed us to compare this effect to the romantic conflict index, which we hypothesized would also be an important predictor of feminist identity and attitudes and support for women’s civil rights. method participants heterosexual volunteers (n = ; women, men) participated in exchange for partial credit toward their in- troductory psychology research participation requirement. of these, ( %) were european american, ( %) were asian american, ( %) were african american, ( %) were latino/a, and the remainder reported another ethnic identity. of the original sample (n = ), par- ticipants were excluded because they indicated they were lesbian, gay, or bisexual ( women, men). feminism and romance measures feminist orientations. following study , participants indicated “how do you feel toward feminists?” on a thermometer scale ranging from (very cold) to (very warm). they also indicated their feminist identity using study ’s index (α = . ). to assess support for women’s civil rights, participants rated their agreement with four items on scales ranging from (strongly disagree) to (strongly agree). the items were: “the u.s. should pass the era (equal rights amendment) to ensure equality for women”; “women should have the same career opportuni- ties that men have”; “women should not have to put up with sexual harassment”; and “women and men should have the same sexual freedoms.” responses were averaged to form the civil rights index (α = . ). romantic conflict. to assess perceived conflict be- tween feminism and romance, we administered four items on scales ranging from (strongly disagree) to (strongly agree). the items were: “most men would probably not want to date a feminist”; “feminism and romance do not mix well for women”; “feminism can cause women to resent men”; and “feminism can add stress to relationships with men.” these were averaged to form the romantic conflict index (α = . ). lesbian stereotype. using the identical scales, partici- pants rated their agreement with four items that were av- eraged to form the lesbian stereotype index (α = . ). the items were: “most feminists are probably lesbians”; “the leaders of the feminist movement tend to be lesbians”; “lesbians have taken over the feminist movement”; and “feminism focuses too much on lesbian issues.” procedure participants were escorted to individual booths equipped with a desktop pc by an experimenter, who then adminis- tered instructions and started the computer program. par- ticipants first completed the measures in the order de- scribed above. following this, they completed demographic measures (i.e., gender, ethnicity, age, and sexual orien- tation). within each measure, items were randomly pre- sented. following completion of these measures, partici- pants were thanked and debriefed. results and discussion gender differences table shows study ’s descriptive statistics separately by gender. not surprisingly, women scored higher than men on the feminist identity, attitude, and civil rights indices. effect sizes were large for each of the variables (d > . for all). although we did not predict gender differences on the romantic conflict and lesbian stereotype indices, table shows that men scored higher than women on both mea- table descriptive statistics as a function of participant gender (study ) women men sex difference measure m sd m sd t d feminist identity . . . . . ∗∗ . feminist attitude . . . . . ∗∗ . civil rights . . . . . ∗∗ . romantic conflict . . . . . ∗∗ −. lesbian stereotype . . . . . ∗ −. note. the effect size (cohen’s d) for gender differences is based on the pooled standard deviation. positive scores indicate women scored higher than men. by convention, small, moderate, and large effect sizes corre- spond to . , . , and . , respectively (cohen, ). ∗p < . . ∗∗p < . . sures. thus, men were particularly likely to view feminism as being in conflict with heterosexual relationships. perceived conflict between feminism and romance our primary hypothesis was that heterosexual women and men would show resistance to feminism to the extent they believed it conflicted with romance. we also sought to com- pare romantic conflict and the lesbian stereotype as predic- tors of feminist identity and attitudes. not surprisingly, the lesbian stereotype and romantic conflict indexes covaried for both women and men (r = . and . , respectively, p < . ), suggesting that the stereotype accounts for the perception that feminism conflicts with romance (or vice versa). nonetheless, we examined their separate relation- ships with feminist orientations. table shows the results separately by gender. as can be seen, the pattern of relationships was sim- ilar for both genders. first, romantic conflict negatively correlated with feminist identity and attitude and support for women’s civil rights. thus, participants who believed that feminism is troubling for romance also showed less table correlations as a function of participant gender (study ) romantic lesbian civil conflict stereotype rights women feminist identity −. ∗∗ −. ∗∗ . ∗ feminist attitude −. ∗∗ −. ∗∗ . ∗∗ civil rights −. ∗ −. — men feminist identity −. ∗∗ −. ∗ . ∗ feminist attitude −. ∗∗ −. ∗∗ . ∗∗ civil rights −. ∗ −. ∗∗ — note. correlations are based on women and men. ∗p < . . ∗∗p < . . rudman and fairchild enthusiasm for feminists and policies that support women. these results support our hypothesis that romance-related concerns about feminism may be an important barrier to gender equity. table also shows similar relationships for the lesbian stereotype index, with one exception. men (but not women) who stereotyped feminists as lesbians also showed less support for women’s civil rights, compared with men who did not endorse this stereotype. the next analysis checked on the ability of the roman- tic conflict and lesbian stereotype measures to contribute unique variance to feminist identity and feminist attitude scores. because feminist identity and attitude scores were highly related for both genders, r > . for both, p < . , we averaged their standardized scores to form a single index of feminist orientations. we then regressed feminist orien- tations on the romantic conflict and lesbian stereotype in- dexes. for men, results showed that romantic conflict, but not the lesbian stereotype, remained a predictor of feminist orientations, β = −. , p < . , and β = −. , p = . , respectively (overall r = . ). the results for women were similar (romantic conflict, β = −. , p < . ; lesbian stereo- type, β = −. , p = . ; overall r = . ). thus, concerns about the influence of feminism on romantic relationships uniquely contributed to weak feminist identity and attitude for men and women alike. similar analyses favored romantic conflict over the les- bian stereotype as a predictor of support for women’s civil rights. for women, romantic conflict was a unique predic- tor, whereas the lesbian stereotype was nonsignificant, β = −. , p < . , and β = −. , p = . , respectively (over- all r = . ). for men, romantic conflict was a marginally significant predictor, whereas the lesbian stereotype was nonsignificant, β = −. , p < . , and β = −. , p = . , respectively (overall r = . ). in sum, study showed that people who viewed femi- nism as troubling for romance were unlikely to show fem- inist orientations or to support women’s civil rights, even after accounting for the lesbian stereotype. thus, study continued to support the hypothesis that romantic con- cerns about feminism have unfavorable implications for the progress of the women’s movement. moreover, study (unexpectedly) suggested that these concerns are more im- portant than the lesbian stereotype when determining par- ticipants’ own feminism. study in study , we examined whether feminism might be viewed as incompatible with satisfying sexual relations. specifically, we hypothesized that female assertiveness and autonomy, mechanisms that promote gender equality, might be seen as undermining heterosexual intimacy, particularly among men. gender socialization includes learning sexual scripts that dictate greater dominance for men, whereas women’s roles are more passive and submissive (impett & peplau, ; sanchez, crocker, & boike, ). as a result, men are more likely to initiate and determine the nature of sex- ual contact (browning, hatfield, kessler, & levine, ). they also exhibit a more dominant sexual drive compared to women (baumeister, catanese, & vohs, ). thus, tra- ditional sexual scripts are at odds with female assertiveness and autonomy, attributes that enhance women’s ability to compete successfully in performance settings. to the ex- tent that individuals presume that, for sex to be satisfying, men must be in charge or dominant and women more sub- missive, they should score low on the feminist attitude and support for civil rights measures. if so, specific concerns about men’s sexual needs may also play a role in preserving sexism. finally, study allowed us to replicate study ’s finding that romantic conflict negatively predicted feminist orien- tations. to enhance the generalizability of our results, we used different measures to assess (a) attitudes toward fem- inism and (b) romantic conflict (i.e., perceptions that fem- inism and romance are incompatible). we expected sexual and romantic conflict to be negative predictors of feminist attitudes and support for women’s civil rights. method participants heterosexual volunteers (n = ; women, men) participated in exchange for partial credit toward their in- troductory psychology research participation requirement. of these, ( %) were european american, ( %) were asian american, ( %) were african american, ( %) were latino/a, and the remainder reported another ethnic identity. of the original sample (n = ), were eliminated because they indicated they were lesbian, gay, or bisexual ( women, men). materials feminist orientations. participants completed the feminist and women’s movement scale (fassinger, ), responding on a scale ranging from (strongly disagree) to (strongly agree). sample items included “feminist princi- ples should be adopted everywhere,” “feminists are a men- ace to society,” and “the women’s movement is too radical and extreme in its views.” after appropriate recoding, items were averaged to form the feminist attitude index (α = . ), on which high scores reflected pro-feminist attitudes. par- ticipants also completed study ’s civil rights index (α = . ). sexual and romantic conflict. as a measure of sexual conflict, participants responded to four items on a scale ranging from (strongly disagree) to (strongly agree). the items were: “men perform better sexually when they are in charge”; “romance depends, in part, on men be- ing allowed to be in charge”; “if men and women behaved the same, it would take the mystery out of love”; and “if feminism and romance table correlations and means as a function of participant gender (study ) women men feminist romantic sexual feminist romantic sexual attitude conflict conflict attitude conflict conflict romantic conflict −. ∗∗ −. ∗∗ sexual conflict −. ∗∗ . −. ∗ . civil rights . ∗∗ −. ∗∗ −. ∗∗ . ∗ −. ∗∗ −. ∗∗ mean . a . a . a . b . a . b sd . . . . . . note. correlations are based on women and men. means not sharing a subscript differ between female and male participants at the p < . level or greater. ∗p < . . ∗∗p < . . women want to be loved, they should not compete against men.” items were averaged to form the sexual conflict index (α = . ). for the measure of romantic conflict, partici- pants rated their agreement with a single item, “feminism has negatively influenced relationships between men and women,” on a scale ranging from (strongly disagree) to (strongly agree). procedure measures were administered by a computer program to par- ticipants in individual booths in the order described above. within each measure, items were randomly presented. par- ticipants were then thanked and debriefed. results and discussion preliminary analyses table shows descriptive statistics for the study vari- ables separately by gender. women scored higher on the feminist attitude index than did men; the effect size was moderate (d = . ). in addition, men showed higher sexual conflict scores than women (d = −. ). that is, men were more likely than women to view female assertiveness and independence as predictors of sexual conflict. in contrast to study , there was no significant gender difference on the romantic conflict scale (d = −. ). that is, women were no less likely than men to agree that feminism has negatively influenced male–female relations. finally, as in study , and not shown in table , women scored higher than men on the civil rights index (m = . vs. . , sd = . and . , respectively, d = . ). predicting feminist orientations from romantic relationship conflicts in line with study , we expected romantic conflict scores to negatively covary with feminist attitudes and civil rights support. to extend study ’s findings, we expected a simi- lar pattern for the sexual conflict index. table shows the key relationships separately by gender. as predicted, the romantic conflict and sexual conflict indexes were nega- tively associated with the feminist attitude and civil rights measures for both genders. the pattern is consistent with the hypothesis that low enthusiasm for feminists may stem, in part, from a perceived conflict between feminism and harmonious romantic relationships. finally, romantic and sexual conflict scores were negligibly related for women and men, rs = . and . , ns, respectively. this suggests that they are distinguishable as predictors of feminist ori- entations. in sum, study ’s findings supported the hypothesis that beliefs about the incompatibility of romance and feminism decrease support for feminism, and we extended our anal- ysis to include specific concerns about sexual harmony. be- cause sexual conflict and romantic conflict scores were un- related, individuals can have independent concerns about the impact of feminism on the health of their intimate rela- tionships; however, each can negatively predict support for feminism and women’s civil rights. general discussion gender represents a unique social category for intergroup relations research because heterosexual men and women rely on each other to fulfill basic needs, including sexual gratification and relational well being. in three investiga- tions, we found support for our hypothesis that intimate re- lationship concerns can undermine feminism’s appeal and, therefore, perhaps undermine collective action on women’s behalf. results consistently showed a negative association between feminist orientations and perceived conflict be- tween feminism and romantic relationship concerns (at- tractiveness, sex appeal, romance, and sexual harmony) for women and men alike. are beauty and romance incompatible with feminism? study revealed that the unattractive feminist stereotype is alive and well, just as it was years ago (goldberg et al., ). both genders rated plain women as more likely to be feminists compared to pretty women. however, the stereo- rudman and fairchild type was fully explained by beliefs that unattractive women are likely to be lesbians. moreover, the negative link be- tween perceived beauty and lesbianism was fully accounted for by the belief that plain women are low on sex appeal (i.e., unpopular dating-wise with men). as a result of these unfavorable beliefs, young adults may view feminism as un- romantic and a hindrance to their own relationships. past research has consistently uncovered a bias against feminists. the present investigations were concerned with the possibility that people may avoid identifying with and liking feminism (i.e., treat it as the f word) to the extent that it is perceived as a roadblock to emotional or sexual hap- piness. support for this hypothesis was shown in studies and . beliefs that feminism was problematic for hetero- sexual relationships negatively predicted feminist identity and attitudes and support for women’s civil rights, even af- ter accounting for the lesbian feminist stereotype (study ) and sexual conflict (study ). although men tended to show higher romantic and sexual conflict scores than women, the predictive utility of these scores vis-à-vis feminist orien- tations was remarkably similar for both genders in both studies. limitations and future directions although we can claim with confidence that a perceived conflict between feminism and romance is linked to low support for feminists, our research cannot speak to the causal direction. future research is needed to determine whether people justify negative reactions to feminists on the basis of relationship concerns, as opposed to these concerns leading to less support for feminism. moreover, our research cannot determine the accuracy of beliefs that feminism is incompatible with romance and sexual intimacy. future investigations should examine whether feminist women (or men with feminist partners) are likely to have troubled relationships, compared with people in tra- ditional relationships. finally, future investigations should employ measures of feminist identity development (bargad & hyde, ; downing & roush, ), as well as feminist activism (stake, roades, rose, ellis, & west, ), which could provide more nuanced results. in concert, the present findings suggest that a mar- riage between romantic relationship and sexism research is overdue when considering the factors that underlie gen- der hegemony. although the fact that gender represents a special case for intergroup relations has been appreciated (fiske & stevens, ; rudman & goodwin, ), the in- fluence of heterosexuality on sexism has been largely over- looked (cf. glick & fiske, ; holland & eisenhart, ; rudman & goodwin, ; rudman & heppen, ). as a result, there are several roads that might be taken by researchers. first, future investigations of the negative link between beauty and perceived feminism are needed to illu- minate its underpinnings. for example, heterosexuals may presume that pretty women can obtain social status and prestige indirectly, through men, and therefore need not commit themselves to obtaining gender parity to the same degree that plain women must to be financially secure. sec- ond, it might be fruitful to explore the relationship between romantic ideology and gender competition. for example, women may be reluctant to change the gender dynamic from benevolence (men protecting women) to competing with men for economic resources for fear that it will impede their love life, including their ability to marry. men, too, might resist a change in this dynamic, given their vested in- terest in male hegemony. in short, romance may be viewed as a means of achieving power more so for women than for men, and this fact may make feminism threatening to women and men for different, as well as similar, reasons. fi- nally, individual differences in the perception that feminism conflicts with romance should be investigated. for example, young women, who may be particularly interested in having romantic relationships, may be more afraid than their older counterparts that men will not want to date them if they are feminists. in addition, women in secure marriages may be less concerned with unromantic perceptions of feminists. the successful protection and enlargement of women’s rights requires women’s enthusiastic defense, which, we suspect, entails recognizing that feminism is not anti-male. instead, feminism is a humanist movement, dedicated to gender equality, rather than benefiting women at the ex- pense of men. therefore, understanding the specific barri- ers to embracing feminism for both genders is critical for guaranteeing its health. for this reason, we believe that a consideration of the implications of heterosexual relation- ships for feminism is long overdue, but will ultimately bear fruit in the struggle to overcome resistance to gender equity. initial submission: april , initial acceptance: february , final acceptance: april , notes . cohen’s d is an effect size measure. by convention, small, mod- erate, and large effect sizes correspond to . , . , and . , respectively (cohen, ). . it is interesting to note that, in their research, unger et al. ( ) found a general tendency for political deviants to be rated as unattractive, not just feminists. . we used photos from to replicate goldberg’s paradigm and because contemporary high school senior photos resem- ble model photo shoots, complete with costumes and various settings. in particular, the overt emphasis on sex appeal (e.g., provocative clothing and poses) prohibited using contempo- rary photos. we used our own judgment to determine pretty and plain targets; a manipulation check from our participants confirmed our decisions (see the results section). . we originally factor analyzed a -item scale and chose the four items in the sexual conflict index because they formed the first factor (eigenvalue = . , variance accounted for = %, all factor loadings > . ), whereas the remaining three feminism and romance items formed the second factor (eigenvalue = . , variance accounted for = %, all factor loadings > . ). the items in the second factor appeared to reflect traditional gender roles (“women should relax and let men be the primary breadwin- ner in the family,” “women and men should not compete for the same jobs,” and “women should not try to succeed in male occupations”). references bargad, a., & hyde, j. s. 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( ). the beauty myth: how images of beauty are used against women. new york: william morrow. introduction 현대사회에는 조직의 목표달성을 이루기 위하여 그 중심에 있 는 조직원들의 인적자원관리에 관심을 집중하고 있는 추세이다. 인적자원관리란 여러 가지의 인적자원활동들로 구성되어 있으 며(kim & bae, ), 전략적 인적자원관리는 종사자의 조직애 착과 직무몰입을 증대시켜 직무수행역량을 강화하고 종사자의 이 직의도를 약화시킨다(song et al., ). 이처럼 인적자원관리 는 가장 기본적이면서도 중요한 요소이며, 조직에 가치를 부여하 고 지속적인 조직의 경쟁우위를 창출하는 자원이라고 할 수 있다 (na, ). 인적자원관리와 관련된 선행 연구를 살펴보면 bae & sa ( )는 인적자원관리와 조직성과에 대한 실증연구를 통해 인적 자원관리 시스템이 조직의 성과에 중요한 영향 요인임을 증명하였 고, chae & kim ( )는 조직수준에서의 자원기반이론을 토대 로 전략적 인적자원관리가 경영성과에 미치는 영향을 연구하여 전 략적 인적자원관리가 경영성과에 유의미한 정(+)의 영향을 미치 는 것을 확인하였다. chang ( )은 공정성 중시 인적자원관리 가 성 평등 조직문화에 미치는 영향을 연구하여 공정성 중시의 인 적자원관리는 성 평등 조직문화에 긍정적인 영향을 미치는 것을 확인하였으며, park & cha ( )는 인적자원관리 제도 중에서 평가보상제도 및 교육훈련제도에 대한 개별 종업원들의 인식이 개 인의 창의적 성과에 미치는 영향을 연구하여 교육훈련제도에 대 한 긍정적인 인식은 창의적 성과와 긍정적 관계를 보이는 것을 확 인하였다. yoo & kim ( )는 헌신형 인적자원관리와 기업성과 의 관계를 연구하여 헌신형 인적자원관리 시스템 구성요소와 시 스템은 기업성과에 모두 정(+)의 영향을 미치는 것을 확인하였으 며, ha & shim ( )은 고몰입형 인적자원관리와 경영성과 간 의 관계에 관한 연구를 하여 고몰입형 인적자원관리가 각각 활용 과 탐험에 정(+)의 영향을 주는 것을 확인하였다. 이처럼 인적자원관리에 관한 많은 연구들이 선행되어왔지만 미 용서비스업 종사자의 특성을 고려한 인적자원관리 연구는 아직 미 r e s e a r c h a r t i c l e open access copyright ⓒ korea institute of dermatological sciences. this is an open access article distributed under the terms of the creative commons attribution non-commercial license (http://creativecommons.org/licenses/by-nc/ . ), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. human resource management according to the characteristics of beauty service workers jung-eun park , ae-jin yoo , eun-jun park * department of hair and makeup design, seokyeong university, seoul, korea department of health industry, sookmyung women's university, seoul, korea *corresponding author: eun-jun park, department of hair and makeup design, seokyeong university, seogyeong-ro, seongbuk-gu, seoul , korea tel.: + fax: + email: ayamdream@hanmail.net received june , revised september , accepted september , published september , abstract purpose: the present study investigates human resource management in the beauty service industry based the characteristics of workers. methods: data were collected from the beauty service industry and analyzed using statistical package for the social sciences (spss) . . frequency analysis, factor analysis, reliability analysis, independent sample t -test, and one-way anova were used for data analysis. results: there were significant differences in human resource management based on gender, age, marital status, education, position, salary, work experience, company type, number of employees, and specialty. conclusion: the study results can be used as basic data for the development of the beauty service industry. in the beauty service industry, systematic human resource management should be based on the characteristics of workers and be planned and managed to achieve the organizations goals. keywords: beauty, service, human resource management, beauty service workers, characteristics issn - (print) issn - (online) asian j beauty cosmetol ; ( ): - http://dx.doi.org/ . /ajbc. . human resource management research of beauty service workers http://dx.doi.org/ . /ajbc. . 비한 실정이다. 이에 본 연구는 미용서비스업 종사자의 특성에 따른 인적자원 관리의 차이를 알아보고 향후 미용서비스업에서의 인적자원관리 방향을 제시하고 효과적인 경영전략을 수립하는데 기초자료를 제 공하는데 목적이 있다. methods . 연구대상자 본 연구의 조사대상은 미용종사자를 대상으로 설정하였다. 년 월 일부터 년 월 일까지 실시되었고 총 부 table . general characteristics of participants items total frequency (n) percentage (%) gender men . women . age teenager . s . s . s . s or older . marital status single . married . divorced . education level graduated from high school . currently attending or graduated from college . currently attending or graduated from university . currently attending or graduated from graduate school . post intern (assistant) . designer (working- level) . director (branch representative) . chairman (representative) . manager . type of wage wage . incentive . others . beauty career years or less . – years . – years . – years . years or more . type of company franchise . private enterprise . others . no. of employees persons or less . – persons . – persons . – persons . persons or more . beauty field hair . makeup . skin care . nail art . others . total . 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 http://www.e-ajbc.org 의 설문지를 배포하여 부가 최종 분석 자료로 사용되었다. . 자료처리 및 분석 수집된 자료는 spss . 프로그램을 활용하여 빈도분석, 요 인분석, 신뢰도분석, 독립표본 t-test, 일원변량분석(one way anova)을 하였다. results and discussion . 조사대상의 일반적 특성 조사대상의 일반적 특성을 알아본 결과는 table 과 같다. 성별 은 남성 . %, 여성 . %로 여성이 높게 나타났다. 이는 park ( )의 연구에서 남성보다 여성의 비율이 매우 높게 나타난 결 table . dimensions of human resource management questions related to human resources management factor factor factor factor education management work management compensation management employment management my company offers employees opportunities for various education and training programs in connection with work. . . . . my company makes much investment in education and training of employees. . . . . my companies provide employees with longer hours of education and training, compared to other companies in the same industry. . . . . my company has a systematic education and training program which employees can participate in. . . . . employees of my company participate extensively in decision-making and problem-solving processes related to their work and working environment. . . . . my company devolves authorities and responsibilities extensively to employees. . . . . my company empowers employees greatly, giving them much discretion. . . . . my company introduces and operates a team system actively for effective performance of work. . . . . in my company, feedback and coaching occur among superiors/colleagues smoothly. . . . . in my company, wage determination criteria are reasonable, transparent, and fair. . . . . my company pays wages relatively higher than those of other companies in the same industry. . . . . i am paid a fair wage for the efforts that i am making. . . . . my company is operating a system that distributes company profits to employees (collective performance-relayed pay system, profit-sharing system, etc.). . . . . my company has proper screening procedures such as tests, interviews, etc., for employment. . . . . my company sets forth clear selection criteria related to skill and ability for employment. . . . . my company considers skills and attitude important for employment. . . . . my company invests much time and financial resources in the screening process in order to select excellent candidates. . . . . unique value . . . . explained variance (%) . . . . cumulative variance (%) . . . . reliability coefficient (cronbach’s α) . . . . human resource management research of beauty service workers http://dx.doi.org/ . /ajbc. . 과와 일치하며 아직까지 미용서비스업에 종사하는 종사자들 중 여 성이 많은 비율을 차지하고 있다는 것을 보여준다. 연령은 대 . %, 대 . %, 대 . %, 대 . %, 대 이상 . %로 대가 가장 높게 나타났다. 결혼여부의 경우 미혼 . %, 기혼 . %, 이혼 . %로 미혼이 가장 높게 나타났다. 학력을 알아본 결과 고등학교 졸업 . %, 전문대학 재학/졸업 . %, 대학교 재학/졸업 . %, 대학원 재학/졸업 . %로 대학교 재학/졸업이 가장 높게 나타났다. 이는 lim & park ( )의 연구에서 대학 교(재학생포함)의 비율이 가장 높게 나타난 결과와 일치하며 과거 에 비해 미용서비스업에 종사하는 종사자들의 학력이 높아지고 있 음을 의미한다. 직급은 인턴(어시스트) . %, 디자이너(실무자) . %, 실장(점장) . %, 원장(대표) . %, 매니저 . %로 인 턴(어시스트)가 가장 높게 나타났다. 급여형태를 알아본 결과 급 여 . %, 인센티브 . %, 기타 . %로 급여가 가장 높게 나타 났다. 미용경력은 년 이하 . %, - 년 . %, - 년 . %, - 년 . %, 년 이상 . %로 년 이하가 가장 높게 나타났 다. 회사형태로는 프랜차이즈 . %, 개인 . %, 기타 . %로 프랜차이즈가 가장 높게 나타났으며, 직원 수는 명 이하 . %, table . differences in human resource management by age age m s.d. f -value (p ) human resources management education management teenager . b . . *** s . ab . s . a . s . a . s or older . a . total . . work management teenager . ab . . *** s . b . s . ab . s . a . s or older . a . total . . compensation management teenager . b . . *** s . b . s . a . s . a . s or older . a . total . . employment management teenager . c . . *** s . bc . s . ab . s . ab . s or older . a . total . . ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. table . differences in human resource management by gender gender m s.d. t -value (p ) human resources management education management men . . . women . . work management men . . . ** women . . compensation management men . . . women . . employment management men . . . women . . **p < . ; m, mean; s.d., standard deviation. 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 http://www.e-ajbc.org - 명 . %, - 명 . %, - 명 . %, 명 이상 . %로 - 명이 가장 높게 나타났다. 미용분야를 알아본 결과 헤어 . %, 메이크업 . %, 피부관리 . %, 네일아트 . %, 기타 . %로 헤어가 가장 높게 나타났다. table . differences in human resource management by education level education level m s.d. f -value (p ) human resources management education management graduated from high school . a . . *** currently attending or graduated from college . a . currently attending or graduated from university . b . currently attending or graduated from graduate school . a . total . . work management graduated from high school . a . . *** currently attending or graduated from college . a . currently attending or graduated from university . b . currently attending or graduated from graduate school . a . total . . compensation management graduated from high school . a . . *** currently attending or graduated from college . a . currently attending or graduated from university . b . currently attending or graduated from graduate school . a . total . . employment management graduated from high school . ab . . ** currently attending or graduated from college . a . currently attending or graduated from university . b . currently attending or graduated from graduate school . ab . total . . **p < . ; ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. table . differences in human resource management by marital status marital status m s.d. f -value (p ) human resources management education management single . a . . ** married . a . divorced . a . total . . work management single . b . . *** married . a . divorced . a . total . . compensation management single . b . . *** married . a . divorced . a . total . . employment management single . a . . *** married . a . divorced . a . total . . **p< . ; ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. human resource management research of beauty service workers http://dx.doi.org/ . /ajbc. . . 인적자원관리의 타당성 및 신뢰도 인적자원관리 문항에 대해 요인분석을 이용한 타당성 검증결과 table 와 같이 교육관리, 직무관리, 보상관리, 채용관리의 네 개의 요인이 도출되었다. bartlett의 단위행렬 점검 결과 χ = . table . differences in human resource management by type of wage type of wage m s.d. f -value (p ) human resources management education management wage . a . . * incentive . a . others . a . total . . work management wage . b . . *** incentive . a . others . a . total . . compensation management wage . b . . *** incentive . a . others . a . total . . employment management wage . b . . ** incentive . ab . others . a . total . . *p < . ; **p < . ; ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. table . differences in human resource management by post post m s.d. f -value (p ) human resources management education management intern (assistant) . b . . * designer (working- level) . b . director (branch representative) . a . chairman (representative) . ab . manager . b . total . . work management intern (assistant) . b . . *** designer (working- level) . b . director (branch representative) . a . chairman (representative) . a . manager . b . total . . compensation management intern (assistant) . c . . *** designer (working- level) . bc . director (branch representative) . a . chairman (representative) . a . manager . b . total . . employment management intern (assistant) . b . . *** designer (working- level) . b . director (branch representative) . a . chairman (representative) . a . manager . b . total . . *p < . ; ***p < . ; duncan test results are a>b>c; m, mean; s.d., standard deviation. 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 http://www.e-ajbc.org (df= , sig= . ), kmo값 . 으로 나타났으며, 공통성은 . 이상으로 나타났다. 요인분석 결과 도출된 네 개의 요인이 전체 분산의 . %이상 설명되고 있는 것으로 나타났다. table . differences in human resource management by type of company type of company m s.d. f -value (p ) human resources management education management franchise . a . . *** private enterprise . b . others . ab . total . . work management franchise . . . private enterprise . . others . . total . . compensation management franchise . . . private enterprise . . others . . total . . employment management franchise . a . . *** private enterprise . b . others . ab . total . . ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. table . differences in human resource management by beauty career beauty career m s.d. f -value (p ) human resources management education management years or less . b . . *** – years . b . – years . a . – years . a . years or more . a . total . . work management years or less . b . . *** – years . b . – years . a . – years . a . years or more . a . total . . compensation management years or less . b . . *** – years . b . – years . a . – years . a . years or more . a . total . . employment management years or less . b . . *** – years . b . – years . a . – years . a . years or more . a . total . . ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. human resource management research of beauty service workers http://dx.doi.org/ . /ajbc. . 인적자원관리에 대한 신뢰성 검증 결과, 신뢰도 계수인 cronbach's α는 . - . 으로 높게 나타나, 신뢰성에는 문 제가 없는 것으로 나타났다. 요인별로 살펴보면, 교육관리 . , 직무관리 . , 보상관리 . , 채용관리 . 로 나타났다. 이러한 결과는 인적자원관리를 근로시간, 급여수준, 교육횟수의 세 개의 요인으로 도출된 chai & park ( )의 연구와 유사함을 확인하였다. . 미용서비스업 종사자의 특성에 따른 인적자원관리 미용서비스업 종사자의 특성(성별, 연령, 결혼여부, 학력, 직급, 급여형태, 근무경력, 회사형태, 직원 수, 전문분야)에 따른 인적자 원관리의 차이를 알아보기 위해 독립표본 t-test, 일원변량분석 (one way anova)을 실시한 결과는 다음과 같다. 사후검증은 던 컨테스트를 사용하였다. ) 성별에 따른 인적자원관리의 차이 직무관리 요인에서 table 와 같이 통계적으로 유의미한 차이 를 보였고(p< . ), 남자의 평균이 여자보다 높게 나타났다. ) 연령에 따른 인적자원관리의 차이 교육관리, 직무관리, 보상관리, 채용관리 요인에서 table 와 같이 통계적으로 유의미한 차이를 보였다(p< . ). 교육관리, 직 무관리, 보상관리 요인은 대의 평균이 가장 높게 나타났고 채용 관리 요인은 대의 평균이 가장 높게 나타났다. ) 결혼여부에 따른 인적자원관리의 차이 교육관리 요인에서 table 와 같이 통계적으로 유의미한 차이 를 보였고(p< . ), 직무관리, 보상관리, 채용관리 요인에서 통계 적으로 유의미한 차이를 보였다(p< . ). 교육관리, 채용관리 요 인은 기혼의 평균이 미혼의 평균에 비해 상대적으로 높게 나타났 으나 던컨테스트 결과 집단으로 분류되지 않았다. 직무관리, 보상 관리 요인은 이혼의 평균이 미혼의 평균에 비해 상대적으로 높게 나타났다. ) 학력에 따른 인적자원관리의 차이 교육관리, 직무관리, 보상관리 요인에서 table 와 같이 통계적 으로 유의미한 차이를 보였고(p< . ), 채용관리 요인에서 통계 적으로 유의미한 차이를 보였다(p< . ). 교육관리, 채용관리 요 인은 전문대학 재학/졸업의 평균이 가장 높게 나타났고 직무관리, 보상관리 요인은 고등학교 졸업의 평균이 가장 높게 나타났다. table . differences in human resource management by no. of employees no. of employees m s.d. f -value (p ) human resources management education management persons or less . c . . * - persons . bc . - persons . ab . - persons . a . persons or more . bc . total . . work management persons or less . a . . * - persons . a . - persons . a . - persons . a . persons or more . b . total . . compensation management persons or less . a . . * - persons . a . - persons . a . - persons . a . persons or more . b . total . . employment management persons or less . c . . *** - persons . b . - persons . ab . - persons . a . persons or more . bc . total . . *p < . ; **p < . ; ***p < . ; duncan test results are a>b>c; m, mean; s.d., standard deviation. 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 http://www.e-ajbc.org ) 직급에 따른 인적자원관리의 차이 교육관리 요인에서 table 과 같이 통계적으로 유의미한 차이 를 보였고(p< . ), 직무관리, 보상관리, 채용관리 요인에서 통계 적으로 유의미한 차이를 보였다(p< . ). 교육관리, 채용관리 요 인은 실장(점장)의 평균이 가장 높게 나타났고 직무관리, 보상관 리 요인은 원장(대표)의 평균이 가장 높게 나타났다. 이러한 결과 는 kim et al. ( )의 직급에 따른 인적자원관리와 조직몰입의 차이를 분석하여 인적자원하위 요인에서 모두 통계적으로 유의한 차이를 보인 것과 유사함을 확인하였다. ) 급여형태에 따른 인적자원관리의 차이 교육관리 요인에서 table 과 같이 통계적으로 유의미한 차이 를 보였고(p< . ), 직무관리, 보상관리 요인에서 통계적으로 유 의미한 차이를 보였으며(p< . ). 채용관리 요인에서 통계적으 로 유의미한 차이를 보였다(p< . ). 교육관리 요인은 기타의 평 균이 가장 높게 나타났으나 던컨테스트 결과 집단으로 분류되지 않았다. 직무관리, 보상관리, 채용관리 요인은 기타의 평균이 가 장 높게 나타났고 급여의 평균이 가장 낮게 나타났다. ) 근무경력에 따른 인적자원관리의 차이 교육관리, 직무관리, 보상관리, 채용관리 요인에서 table 과 같이 통계적으로 유의미한 차이를 보였다(p< . ). 교육관리, 직 무관리, 채용관리 요인은 년 이상의 평균이 가장 높게 나타났고 보상관리 요인은 년에서 년 이상의 평균이 가장 높게 나타났 다. ) 회사형태에 따른 인적자원관리의 차이 교육관리, 채용관리 요인에서 table 과 같이 통계적으로 유 의미한 차이를 보였다(p< . ). 교육관리, 채용관리 요인 모두 프랜차이즈의 평균이 가장 높게 나타났다. ) 직원 수에 따른 인적자원관리의 차이 교육관리 요인에서 table 과 같이 통계적으로 유의미한 차이 를 보였고(p< . ), 직무관리, 보상관리 요인에서 통계적으로 유 의미한 차이를 보였으며(p< . ), 채용관리 요인에서 통계적으로 유의미한 차이를 보였다(p< . ). 교육관리 요인은 명에서 명의 평균이 가장 높게 나타났고 직무관리 요인은 명 이하의 평 균이 가장 높게 나타났다. 보상관리 요인은 명에서 명의 평 table . differences in human resource management by beauty field beauty field m s.d. f -value (p ) human resources management education management hair . a . . *** makeup . ab . skin care . b . nail art . a . others . a . total . . work management hair . a . . *** makeup . a . skin care . b . nail art . a . others . a . total . . compensation management hair . ab . . ** makeup . a . skin care . b . nail art . a . others . a . total . . employment management hair . a . . makeup . a . skin care . a . nail art . a . others . a . total . . **p < . ; ***p < . ; duncan test results are a>b; m, mean; s.d., standard deviation. human resource management research of beauty service workers http://dx.doi.org/ . /ajbc. . 균이 가장 높게 나타났고 채용관리 요인은 명에서 명의 평균 이 가장 높게 나타났다. ) 전문분야에 따른 인적자원관리의 차이 교육관리, 직무관리 요인에서 table 와 같이 통계적으로 유 의미한 차이를 보였고(p< . ), 보상관리 요인에서 통계적으로 유의미한 차이를 보였다(p< . ). 이는 lee & kim ( )의 연 구에서 보상제도가 직무만족도에 정(+)의 영향을 미친다는 결과 와 유사함을 확인하였다. 교육관리, 보상관리 요인은 네일아트의 평균이 가장 높게 나타났고 직무관리 요인은 기타, 메이크업의 평 균이 가장 높게 나타났다. conclusion 첫째, 조사대상의 일반적 특성을 알아본 결과, 성별은 여자, 연 령은 대, 결혼여부는 미혼, 학력은 대학교 재학/졸업, 직급은 인턴(어시스트), 급여형태는 급여, 미용경력은 년 이하, 회사형 태는 프랜차이즈, 직원 수는 - 명, 미용분야는 헤어가 가장 높 게 나타났다. 둘째, 인적자원관리의 타당도 및 신뢰도를 알아본 결과, 교육관 리, 직무관리, 보상관리, 채용관리의 네 개의 요인으로 도출되었 다. 셋째, 미용서비스업 종사자의 특성에 따른 인적자원관리의 차 이를 알아본 결과, 인적자원관리는 성별, 연령, 결혼여부, 학력, 직급, 급여형태, 근무경력, 회사형태, 직원 수, 전문분야에 따라 유의미한 차이가 있는 것으로 나타났다. 연령과 근무경력이 높아 짐에 따라 인적자원관리의 차이가 높게 나타난 것은 미용서비스업 은 처음 시작하는 단계는 힘들지만 일을 할수록 근무환경이 좋아 지는 것이라 판단된다. 이는 반대로 연령이 낮은 미용서비스업을 처음 시작하는 단계의 종사자들의 인적자원관리가 더욱 활발히 이 루어져야 한다는 것을 보여주고 있다. 이에 미용서비스업에서는 조직의 목표달성을 위하여 종사자의 특성을 고려한 체계적인 인적자원관리를 계획하고 진행하여야 할 것으로 사료된다. references bae j, sa j. the effects of human resource management systems on organizational performance. korean journal of management, : - , . chai co, park yj. a study on the relationship between performance of small • medium enterprises and human resource management: focused on root manufacturing industry. the journal of humanities and social sciences, : - , . chang ys. effect of justice-oriented human resource management on gender equality organizational culture. the journal of professional management, : - , . chae js, kim cj. the impact of strategic human resource management on management performance through organizational competence. journal of human resource management research, : - , . ha sw, shim ds. a study on the relationship between high-commitment human resource management and firm performance: mediating roles of exploitation and exploration. journal of human resource management research, : - , . kim jh, seo hs, lee eh. the effect of human resource management on the organizational commitment of the beauty industry professionals. journal of the korean society of design culture, : - , . kim jk, bae sr. a study on the relationship between human resource management practices and corporate financial performance. journal of human resource management research, : - , . lee dh, kim bh. an effect on satisfaction with duty, directivity to customers, and outcome of management of compensation system and duty education over golf workers. journal of golf studies, : - , . lim yk, park ej. effects of organizational identification on organizational phase and relative deprivation of beauticians. asian journal of beauty and cosmetology, : - , . na ig. the analysis on the effect of training on hr outcomes and organizational outcomes. journal of human resource management research, : - , . park sj. mediating effects of organizational commitment on the relationship between beauty industry managers’ leadership and customer orientation. asian journal of beauty and cosmetology, : - , . park ow, cha js. the perception of hrm practices and creative performance: moderating effect of motivation preference. the korean journal of human resources development quarterly, : - , . song er, park kh, moon js. the moderating effects of job 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 http://www.e-ajbc.org embeddedness in the relationship between strategic human resource management and job competence, turnover intention. korean journal of resources development, : - , . yoo bh, kim dj. influence of high commitment human r e s o u r c e m a n a g e m e n t o n f i r m p e r fo r m a n c e : consistency hypothesis and mediating ef fect of employee’s perception. journal of human resource management research, : - , . human resource management research of beauty service workers http://dx.doi.org/ . /ajbc. . 국문초록 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 박정은 , 유애진 , 박은준 * 서경대학교 헤어•메이크업디자인학과, 서울, 한국 숙명여자대학교 헬스산업학과, 서울, 한국 목적: 본 연구는 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 알아보고자 한다. 방법: 미용서비스업 종사자를 대상으로 자료를 수집하였고, statistical package for the social sciences (spss) . 을 이용하여 분석하였다. 분석방법은 빈도분석, 요인분 석, 신뢰도분석, 독립표본 t-test, 일원변량분석(one way anova)이 사용되었다. 결과: 인적자원관리는 성별, 연령, 결혼여부, 학 력, 직급, 급여형태, 근무경력, 회사형태, 직원 수, 전문분야에 따라 유의미한 차이가 있는 것으로 나타났다. 결론: 본 연구결과가 미 용서비스업의 발전을 위한 기초자료로 활용되기를 바라며, 미용서비스업에서는 조직의 목표달성을 위하여 종사자의 특성을 고려한 체계적인 인적자원관리를 계획하고 진행하여야 할 것으로 사료된다. 핵심어: 미용, 서비스업, 인적자원관리, 미용서비스업 종사자, 특성 참고문헌 김종관, 배상림. 인적자원관리활동과 기업 재무성과와의 관계에 관한 연구. 인적자원관리연구, : - , . 김지현, 서현숙, 이은희. 뷰티산업종사자의 인적자원관리가 조직몰입에 미치는 영향. 한국디자인문화학회지, : - , . 나인강. 기업의 훈련이 근로자의 인적자원성과 및 기업성과에 미치는 영향. 인적자원관리연구, : - , . 박선주. 미용산업 경영자의 리더십과 고객지향성 관계에 대한 조직몰입의 매개효과. 아시안뷰티화장품학술지, : - , . 박오원, 차종석. 인적자원관리 제도에 대한 인식과 창의적 성과 간의 관계: 동기부여 선호도의 조절효과. hrd연구, : - , . 배종석, 사정혜. 인적자원관리와 조직성과에 대한 실증연구. 인사조직연구, : - , . 송은란, 박계홍, 문재승. 전략적 인적자원관리와 직무수행역량 및 이직의도의 관계에서 직무배태성의 조절효과. 인적자원 개발연구, : - , . 유병흥, 김동주. 헌신형 인적자원관리와 기업성과의 관계: 일관성 가설과 조직구성원 인식의 매개효과를 중심으로. 인적자 원관리연구, : - , . 이동현, 김봉현. 골프장 종사자들의 보상제도와 직무교육이 직무만족, 고객지향성 및 경영성과에 미치는 영향. 골프연구, : - , . 임윤경, 박은준. 미용종사자의 조직 동일시가 조직위상과 상대적 박탈감에 미치는 영향. 아시안뷰티화장품학술지, : - , . 장용선. 공정성 중시 인적자원관리가 성 평등 조직문화에 미치는 영향. 전문경영인연구, : - , . 채주석, 김찬중. 전략적 인적자원관리가 조직역량을 통해 경영성과에 미치는 영향. 인적자원관리연구, : - , . 채창옥, 박영주. 중소기업의 성과와 인적자원관리 간 관계에 관한 연구: 뿌리산업체를 중심으로. 인문사회 , : - , . 하성욱, 심덕섭. 고몰입형 인적자원관리와 경영성과 간의 관계에 관한 연구. 인적자원관리연구, : - , . 미용서비스업 종사자의 특성에 따른 인적자원관리 연구 http://www.e-ajbc.org 中文摘要根据美容服务工作者的特性研究人力资源管理朴貞恩，劉愛眞，朴銀俊 * 西京大学美发美容设计科，首尔，韩国淑明女子大学健康产业学科，首尔，韩国目的: 本研究以美容工作者的特点为基础，研究美容服务业的人力资源管理。方法: 研究对象来自美容服务行从事者，并使用社会科学统计软件包（spss） . 进行分析。频率分析，因子分析，可靠性分析，独立样本t检验和单向anova用于数据分析。结果: 基于性别，年龄，婚姻状况，教育程度，职位，工资，工作经历，公司类型，员工人数和专业，人力资源管理存在显着差异。结论: 研究结果可作为美容服务业发展的基础数据。在美容服务行业，系统的人力资源管理应该基于工作者的特点，并进行规划和管理，以实现组织目标。关键词: 美容，服务业，人力资源管理，美容服务业从事者，特性 untitled annals of actuarial science, vol. , part , pp. – . & institute and faculty of actuaries doi: . /s guest editorial sexless and beautiful data: from quantity to quality montserrat guillén* department of econometrics, riskcenter-irea, university of barcelona, spain actuarial science has received an enormous influence from statistics since the early times. however, in the recent decades, the interplay between those two disciplines is somehow different compared to the past, with more emphasis on large-scale data analysis and prediction modelling based on customer historical records. in this respect, very little seems to have been said about the quality of data that are being stored in insurance companies’ databases, even though data are the fuel for actuarial modelling. the first idea that came into my mind when the editor invited me to write this guest editorial was to address gender discrimination. the new european regulation, that is supposed to be effective at the end of , imposes a ban on insurance services which are not allowed to treat men and women as different types of customers. no news, on the grounds that this is already the case in some other parts of the globe. but then i thought this topic is just a small grain of sand in the desert, compared to a much wider problem. how much data on customers is gathered by insurers? is it worth storing billions of megabytes? who takes care about data quality? how dependent are we on the good quality of insurance data? unfortunately, we all believe, and especially it departments do, that a treasure is hidden in the databases. something that is unknown, but extremely valuable. as a result, a significantly larger amount of budget is spent on backing up, than on looking at what is useful in the data files. let me first briefly comment on the european gender nightmare and then, in the second part, i will return to the importance of data quality. gender discrimination and lifestyle habits gender is a simple variable usually having at most four levels: man, woman, unknown or not applicable. the latter is used when a policyholder is not a person but a legal entity. however, let us concentrate on humans. gender has been used by ancient actuaries, but our modern view in europe is about to terminate the male/female dichotomy when setting insurance policy prices. gender potentially splits the population of policyholders into two equally sized groups, so we are not talking about a small fraction of high-risk or low-risk individuals, we are talking about two big segments. i want to emphasize that it is well known by insurance economists that banning costless categorization (like gender) is inefficient (see crocker & snow, ; finkelstein et al., , and *correspondence to: dr m. guillén, department of econometrics, university of barcelona, diagonal, , barcelona, spain. tel: . fax: . e-mail: mguillen@ub.edu https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core rothschild, ). as a consequence, i find it strange that in the current state of economic crisis, our regulatory bodies impose rules that are known to damage performance, rather than promoting solutions, such as partial social insurance, that are known to address categorization efficiently. no one seems to have evaluated the aggregated impact on european consumers of banning decisions based on gender, and only a few have talked about the implications for insurers, while some corrupt the whole scene as they find this the perfect excuse to unduly inflate prices and blame others. let us admit that we cannot even mention gender when pricing life and non-life policies from now on in the eu. should actuaries still work under the premise that gender is a risk factor? the obvious answer is yes. but then, the incoming regulation clearly separates the role of actuaries from the role of marketing and sales departments. yet another contradiction. while we advocate that risk management has to be integrated in all parts of the insurance business process, we just build a wall between actuaries, for whom gender should be maintained to assess portfolio risk, and price designers, for whom it should not. a naive and quick solution, suggested to me by a young actuary a few months ago, is to end up with the problem and cope with the regulation. delete that, now annoying, gender item from all customer data files. i would not do that. i would keep gender information for risk management if i think that for internal reasons it is beneficial, even if not allowed for external purposes. the content of a gender variable has much valuable information about the portfolio composition because it is a virtually costless categorization. gender is correct and reliable information about the insured. the alternative way out suggested by theoretical insurance economists is the creation of a varied menu of contracts from which insureds should choose, and thus reveal information. it is a valuable thought, but it may be too slow in practice. however, i find it interesting as it could re-inspire the concept of ‘‘best restaurant’’ awards. so, what are the next steps? a) keep gender, a variable that once upon a time was a good predictor. use it to assess risk, or potential adverse selection in the portfolio. b) start correlating gender information with every single piece of data for the corresponding customer. sooner or later another indicator will prove to be both legal and about as good a predictor as gender. c) introduce lifestyle information in actuarial modelling, which is well known to be even more informative than gender. the main problem when replacing gender information by lifestyle data is moral hazard and the cost of verifying that a policyholder has not provided fraudulent information. and there we get to the quality issue. data quality banning the use of a variable for pricing could indicate a concern about the content of historical information. this is far from reality. no one seems to care much about the use and abuse of data storage. data are accumulated in insurance companies, just in case they are needed, and as a brute source of information. it has become increasingly cheaper to store in the cloud, somewhere, even on a daily basis. m. guillén https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core how do we, as actuaries, use statistical data? in general, data are assumed to be perfect, fixed and known. model predictions are conditioned on the fact that databases are magically ideal, so-called ‘‘clean’’. no information on data quality, measurement error, or the like, is usually provided in research papers that show empirical work. i would advocate in favour of many more contributions with an empirical content to be published, and i would also require authors to provide extensive information and details about how they addressed missing data, imputation practices or sampling designs, whenever necessary. something that is common in many other scientific fields should also become routine in ours. this is vital if we want to promote a balance between theoretical advances and practical implementations. we need to be very rigorous when it comes to presenting and evaluating applied actuarial modelling. having myself been involved in the analysis of many insurance databases, i can confirm that looking into the data usually absorbs much time, but it also guides model specification in the right direction. sound empirical contributions in our scientific journals should be required to comply with these minimum rules. as far as practice is concerned, real-life huge data sets require data quality assessment. measuring data quality is a concept that has six dimensions: validity, integrity, completeness, consistency, accuracy and timeliness. validity refers to the recorded values actually lying within the range of possible values. integrity is coherence among entities and attributes, like birth date being prior to driving license issuance date, for instance. completeness shows that necessary data is present. those three magnitudes are easily verifiable. the other three turn out to be an achilles’ heel. consistency, which refers to duplication and cross-systems checks, accuracy, which indicates that data require verification, and timeliness, which means that the information should constantly be updated, are difficult in practice. i strongly support further cooperation between actuaries, who are the end-users of data, and data managers, who are responsible for databases, when defining key performance and data quality indicators. expert opinion and qualitative information is still far from being optimally integrated in statistical modelling, but some signs indicate a looming revolution in this direction (martı́nez miranda et al., ). moreover, there has been an explosion of new methods in statistical science that are readily applicable to actuarial problems. most of those methods rely on an intensive use of good quality data. to name only a few examples: kernel smoothing (bolancé et al., ), hierarchical models (frees & valdez, ), panel data analysis (boucher & denuit, ), and multi-level models (antonio et al., ). those advances in applied statistics would mean a lot more to us, should the quality of insurance information be higher than it is at present. concluding remarks insurers spend money in making data servers secure. however, much of the precious information in the data is currently hidden in just a small group of variables, which are really the ones that are neat and verifiable, or in qualitative sources. these are beautiful data. i want to thank all of you to let me share my thoughts on gender discrimination as an open window to this much richer spectrum of problems. my view is that more attention should be given to data analysis prior to actuarial modelling. data quality rather than data quantity is the right way to go to improve actuarial models in the future. so, while we make this future possible, let me share with you the joy of reading the current issue of annals of actuarial science. guest editorial https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core references antonio, k., frees, e.w. & valdez, e.a. ( ). a multilevel analysis of intercompany claim counts. astin bulletin, the journal of the international actuarial association, ( ), – . bolancé, c., guillén, m. & nielsen, j.p. ( ). kernel density estimation of actuarial loss functions. insurance: mathematics and economics, ( ), – . boucher, j.p. & denuit, m. ( ). fixed versus random effects in poisson regression models for claim counts: case study with motor insurance. astin bulletin, , – . crocker, k. & snow, a. ( ). the efficiency effect of categorical discrimination in the insurance industry. journal of political economy, ( ), – . finkelstein, a., poterba, j. & rothschild, c. ( ). redistribution by insurance market regulation: analyzing a ban on gender-based retirement annuities. journal of financial economics, ( ), – . frees, e.w. & valdez, e.a. ( ). hierarchical insurance claims modeling. journal of the american statistical association, ( ), – . martı́nez miranda, m.d., nielsen, j.p. & verrall, r. 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( ). the efficiency of categorical discrimination in insurance markets. journal of risk and insurance, , – . m. guillén https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core science american assoclation for the advancement of science science serves its readers as a forum for the presentation and discussion of important issues related to the advance- ment of science, including the presentation of minority or con- flicting points of view, rather than by publishing only material on which a consensus has been reached. accordingly, all ar- ticles published in science-including editorials, news and comment, and book reviews-are signed and reflect theindi-, vidual views of the authors and not official points of view adopted by the aaas or the institutions with which the au- thors are affiliated. publisher: william d. carey editor: daniel e. koshland, jr. deputy editors: philip h. abelson (engineering and applied sciences); john . brauman (physical sciences); gardner lindzey (social sciences) editorial staff managing editor: patricia a. morgan assistant managing editors: nancy j. hartnagel, john e. ringle senior editors: eleanore butz, lawrence . grossman, ruth kulstad associate editors: martha collins, barbara jasny, katrina l. kelner, edith meyers lettes editor: christine gilbert book reviws: katherine livingston, editor this weekin science: ruth levy guyer chief production editor: ellen e. murphy editing depatment: lois schmitt, head, caitilin gordon, mary mcdaniel, barbara e. patterson copy desk: lyle l. green, sharon ryan, beverly shields, anna victoreen production manager: karen schools graphics and production: john baker, assistant manager; holly bishop, kathleen cosimano, eleanor wamer cover editor: grayce finger manuscript systems analyst: william carter news staff new editor: barbara j. culliton new and comment: colin norman, deputy editor; mark h. crawford, constance holden, eliot marshall, r. jeffrey smith, marjorie sun, john walsh reserch news: roger lewin, deputy editor; deborah m. bames, richard a. kerr, gina kolata, jean l. marx, arthur l. robinson, m. mitchell waldrop european correspondent: david dickson business staff associte publisher: william m. miller, ill busines staff supervisor: deborah rivera-wienhold associate busines supervisor: leo lewis membemhip recrultment: gwendolyn huddle member and subscription records: ann ragland guide to biotechnology products and instruments editor: richard g. sommer advertising representatives director: earl j. scherago productlon manager: donna rivera advetising sales manager: richard l. charles marketng manager: herbert l. burklund sais: new york, ny : j. kevin henebry, broad- way ( - - ); scotch plains, nj : c. richard callis, unami lane ( - - ); chicago, il : jack ryan, room , n. michigan ave. ( - - ); san jose, ca : bob brindley, s. st. ( - - ); dorset, vt : fred w. dieffenbach, kent hill rd. ( - - ). instructions for contributors appears on page xi of the june issue. editorial correspondence, including re- quests for permission to reprint and reprint orders, should be sent to h street, nw, washington, dc . tele- phone: - - . advertising correspondence should be sent to tenth floor, broadway, ny . telephone - - . s seprember i volume number beauty, balance, and mathematics n ow that female beauty has been reduced to a formula (eye width, three-tenths of the width of the face; chinlength, one-fifth of the height of the face; area of the nose, less than percent of the area of the face*), we await the arrival of a formula for the ideal journal. the reader might wonder how decisions can be made in the absence of such mathematical precision. there are indeed historical, philosophical, and economic considerations thatguide the policy of a journal. scice is designed for the sophisticated scientist. why sophisticated? because, of course, like beauty, interest in a journal is in the eye of the beholder. science is a relatively thin magazine compared to most specialty journals, yet it covers the entire range of scientific disciplines. thus it is inevitable that only a small fraction of the articles can be in an individual scientist's subdiscipline. the more curious the reader is about the entire range of science, the more likely he or she is to find something of interest in our pages. a frequent comment is that science is biased toward the biological sciences. that is historically true, and newton's laws of motion apply to magazines as they do to bodies falling through space: to change trajectories requires enormous force. it is the goal of this magazine, of this editor, and of the american association for the advancement of science, which represents all of science, to increase participation of scientists in nonbiological disciplines. to do this at the expense of biological science at a time when biology is flourishing in what appears to be its golden age would be folly. therefore, the aaas has wisely decided to add pages to the magazine in order to increase the participation of the physical and social sciences without diminishing the contributions of biological sciences. balance does not mean that each part of the magazine in each issue will have the same proportion of space for the various fields. our news department emphasizes the physical sciences, as space science and weaponry occupy an unusually large portion of the news. reports emphasize biology. solicited articles, research news, and book reviews reflect our attempts to increase coverage of social and physical sciences. we interpret balance in terms of the entire magazine, and our goal is toensure that each issue contains items of interest to every type of scientist. balance is not achieved by giving every subspecialty equal weight. fields that flourished in the past may not be as productive in the present and "the past" can be a mere few years ago. we do not wish to forget the past, but we want to emphasize the present and the future. in the selection process, the economics of publication must play a role. for a wide circulation magazine such as scienc (subscriptions , ) compared to specialty journals (circulations in the , to , range), the cost of printing and mailing is enormous. if we want to keep the magazine por.table, economical, and comprehensive, topics of the widest impact must be given priority. seminal articles in any area are welcome, even if they may be difficult reading for many. intense joy to a small minority of our readership can be as important as mild pleasure to the majority of our audience. an author's anguish when we reject an excellent paper with the statement that it is more appropriate for a specialized journal is matched by our own. this painfuil selection process is not driven by economics alone; it is also a service to our readers to present a distillation of the best and most general. magazines, like species, must adapt to optimize their survival in an ever-changing world. mutations can occur from within or by suggestions from readers, and this editor particularly welcomes ideas for new features, new emphases, and new concepts. those who think that their particular specialty is being neglected are encouraged to send specific suggestions to us. we would hope that a mathematical formula would arise to select the good mutations, but in the interim the editor's receptors will have to respond in a serendipitous manner to the most attractive intellectual pheromones provided by our writers and scientists.-daniel e. koshland, jr. *m. cunningham, , pm. so. psycbol. , ( ). s september i editorial i o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/ beauty, balance, and mathematics daniel e. koshland jr. doi: . /science. . . ( ), . science article tools http://science.sciencemag.org/content/ / / references http://science.sciencemag.org/content/ / / #bibl this article cites articles, of which you can access for free permissions http://www.sciencemag.org/help/reprints-and-permissions terms of serviceuse of this article is subject to the is a registered trademark of aaas.sciencescience, new york avenue nw, washington, dc . the title (print issn - ; online issn - ) is published by the american association for the advancement ofscience by the american association for the advancement of science. o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/content/ / / http://science.sciencemag.org/content/ / / #bibl http://www.sciencemag.org/help/reprints-and-permissions http://www.sciencemag.org/about/terms-service http://science.sciencemag.org/ atp synthases from archaea: the beauty of a molecular motor biochimica et biophysica acta ( ) – contents lists available at sciencedirect biochimica et biophysica acta journal homepage: www.elsevier.com/locate/bbabio review atp synthases from archaea: the beauty of a molecular motor gerhard grüber a,⁎, malathy sony subramanian manimekalai a, florian mayer b, volker müller b,⁎ a school of biological sciences, nanyang technological university, nanyang drive, singapore , republic of singapore b molecular microbiology & bioenergetics, institute of molecular biosciences, johann wolfgang goethe university frankfurt/main, max-von-laue-str. , frankfurt, germany ⁎ correspondence to: g. grüber, school of biological sc university, singapore , republic of singapore. t and v. müller, molecular microbiology & bioen biosciences, johann wolfgang goethe university frankf frankfurt, germany. tel.: + ; fax: + e-mail addresses: ggrueber@ntu.edu.sg (g. grüber), v (v. müller). http://dx.doi.org/ . /j.bbabio. . . - /© elsevier b.v. all rights reserved. a b s t r a c t a r t i c l e i n f o article history: received november received in revised form march accepted march available online march keywords: atpase na+ bioenergetics energy conservation methanogenesis rotary enzyme c ring archaea live under different environmental conditions, such as high salinity, extreme phs and cold or hot tem- peratures. how energy is conserved under such harsh environmental conditions is a major question in cellular bioenergetics of archaea. the key enzymes in energy conservation are the archaeal a ao atp synthases, a class of atp synthases distinct from the f fo atp synthase atp synthase found in bacteria, mitochondria and chloro- plasts and the v vo atpases of eukaryotes. a ao atp synthases have distinct structural features such as a collar- like structure, an extended central stalk, and two peripheral stalks possibly stabilizing the a ao atp synthase dur- ing rotation in atp synthesis/hydrolysis at high temperatures as well as to provide the storage of transient elastic energy during ion-pumping and atp synthesis/-hydrolysis. high resolution structures of individual subunits and subcomplexes have been obtained in recent years that shed new light on the function and mechanism of this unique class of atp synthases. an outstanding feature of archaeal a ao atp synthases is their diversity in size of rotor subunits and the coupling ion used for atp synthesis with h+, na+ or even h+ and na+ using enzymes. the evolution of the h+ binding site to a na+ binding site and its implications for the energy metabolism and physiology of the cell are discussed. © elsevier b.v. all rights reserved. . introduction life under extreme conditions — some like it salty, some acidic, some cold or hot! adaptation of archaea to different environmental conditions requires special cellular adaptation mechanisms to confer life and stabil- ity of proteins at temperatures at or above °c, at salt concentrations up to m or at phs ranging from to . ever since archaea have been isolated, especially the hyperthermophilic archaea have attracted much interest. hyperthermophilic organisms, which are defined as having opti- mal growth temperatures above or at °c, were discovered over years ago [ ]. since then more than hyperthermophilic species have been isolated. the world records in growth at high temperatures are held by pyrococcus furiosus, which grows at an optimal temperature of °c [ ], pyrodictium occultum, which grows from °c to °c [ ], hyperthermus butylicus, which grows up to °c [ ], methanopyrus kandleri, which grows up to °c [ ] and pyrolobus fumarii, which grows between °c and °c (at a pressure of . kpa) and that can also withstand autoclaving at °c [ ]. so far no hyperthermophilic organism has yet been discovered growing at temperatures above °c, iences, nanyang technological el.: + ; fax: + ergetics, institute of molecular urt/main, max-von-laue-str. , . mueller@bio.uni-frankfurt.de but their existence is not impossible. hyperthermophiles are the deepest branching organisms of the bacterial and archaeal s rrna-based phylogenetic trees and are considered therefore to represent “early organisms” adapted to the conditions similar to those found on the early earth [ , – ]. hyperthermophiles were isolated from geothermal- ly heated environments like submarine hydrothermal vents, from the walls of “black smoker” hydrothermal vent chimneys, hot marine sediments or hot springs, where hydrogen gas is found at high levels due to volcanic outgassing [ – ] or by abiotic production [ , ]. this review will introduce the strategies of energy conservation in archaea and the key component in cellular bioenergetics, the a ao atp synthase. unlike energy conservation mechanism in eukaryotes and bacteria, in archaea, like methanogens, metabolism is coupled to the generation of a h+- and/or na+-gradient across the membrane, and both ion gradients drive the synthesis of atp [ ]. the a ao atp synthase, catalyzing the synthesis of atp, is composed of nine subunits in a proposed stoichiometry of a :b :c:d:e :f:h :a:cx. the enzyme possesses a water-soluble a sector, containing the catalytic sites, and an integral membrane ao domain, involved in ion translocation [ ]. a variety of structural approaches have given a deeper insight into the structural details of individual a ao atp synthase subunits as well as subcomplexes, and have revealed important evolutionary structural de- tails that lead to variations in nucleotide recognition and mechanism of atp synthesis and/or atp hydrolysis of the biological nanomachine a ao atp synthase, when compared with the evolutionary related f fo atp synthases and eukaryotic v vo atpases. http://crossmark.crossref.org/dialog/?doi= . /j.bbabio. . . &domain=pdf http://dx.doi.org/ . /j.bbabio. . . mailto:ggrueber@ntu.edu.sg mailto:vmueller@bio.uni-frankfurt.de http://dx.doi.org/ . /j.bbabio. . . http://www.sciencedirect.com/science/journal/ g. grüber et al. / biochimica et biophysica acta ( ) – . energy conservation in archaea the principle mechanisms of energy conservation known to date, e. g. chemiosmosis or substrate level phosphorylation (slp) were invented very early in evolution and are found also in archaea, but due to their phylogenetic position, very close to the root of the tree of life, it is hypothesized that ancient forms of chemiosmosis are present in archaea [ ]. up to now five phyla are present in the domain archaea. the euryarchaeota, containing methanogens, hyperthermophilic and halophilic archaea, and crenarchaeota with archaea having a sulfur metabolism (including some hyperthermophiles), are the two major phyla of archaea. thaumarchaeota are closely related to the crenarchaeota and contain ammonia-oxidizing archaea. the phyla nanoarchaeota and korarchaeota are represented only by one species nanoarchaeum equitans and korarchaeum cryptofilum, respectively which are very close to the root of the tree of life. archaea are physiologically enormously heteroge- neous. they can grow heterotrophically on various compounds and use substrate level phosphorylation (slp) to synthesize atp in combination with chemiosmosis. under anaerobic conditions energy can be conserved by fermentation, anaerobic respiration with nitrate, anaerobic photores- piration using bacteriorhodopsin as well as proton-pumping hydroge- nases and sodium ion-pumping methyltransfer reactions [ , ]. especially the hydrogenases are of great interest since hydrogen certainly was around in early earth and is used by a number of archaea as an electron donor. in the following section a brief introduction to hydrogen-dependent energy conservation mechanisms will be given. for more comprehensive reviews, the reader is referred to recent reviews [ – ]. p. furiosus, a hyperthermophilic strictly anaerobic archaeon that belongs to the phylum euryarchaeota, conserves energy for growth by fermentation of carbohydrates and peptides to co , h and organic acids, e.g. acetate, in the absence of elemental sulfur [ ]. hydrogen is evolved by hydrogenases with reduced ferredoxin as an electron donor. ferredoxin plays a central role in the energy metabolism of many anaerobic archaea (and bacteria). it has a redox potential well below − mv, up to − mv, and thus can be used to reduce pro- tons to hydrogen gas (e ′ = − mv). this exergonic reaction is used to pump ions out of the cell, most likely na+, and the electrochemical na+ gradient established is then used to drive atp synthesis [ ]. this multisubunit membrane-bound hydrogenase (mbh) has eight subunits comprising a hydrogen-oxidizing module as well as na+/h+ antiporter modules [ ]. thus, for the subunit composition the mbh resembles modern complex i enzymes and indeed, hydrogenases are the evolu- tionary precursor of complex i found in mitochondria or bacterial membranes. in p. furiosus, the hydrogenase is used to generate an elec- trochemical ion potential (Δeμna þ ) for transport processes and other energy-consuming membrane reactions but most of the cellular atp is generated by substrate level phosphorylation during glycolysis [ ]. this is different in thermococcus onnurineus that can grow by oxidation of formate to carbon dioxide and hydrogen. this reaction is close to the thermodynamic equilibrium and actually is the reaction with the lowest Δg known to sustain life (− . kj/mol) [ , ]. the reaction sequence is simple and involves a formate dehydrogenase that oxidizes formate and channels electrons to a membrane-bound hydrogenase, very simi- lar to the enzyme described above for p. furiosus [ , ]. electron trans- fer to protons leads to the generation of an ion gradient that then drives atp synthesis. although this has not been addressed experimentally, atp synthesis is suggested to involve na+ as a coupling ion. a unique pathway that allows growth under strictly anaerobic conditions is methanogenesis. methanogens use only chemiosmosis for energy conservation and couple methanogenesis to the generation of two primary ion gradients [ ]. one of these ion gradients is a primary, electrochemical sodium ion gradient established by the methyltetrahydromethanopterin–coenzyme m methyltransferase (mtr) [ , ]. this reaction is common to every methanogen. some methanogens also have an additional electron transport chain(s) that includes cytochromes and have evolved a second, additional mecha- nism to energize their membranes. this proton-motive electron trans- port chain leads to a heterodisulfide of coenzyme m and coenzyme b as an electron acceptor [ , ]. therefore, methanogenic archaea, which have a methyltetrahydromethanopterin–coenzyme m methyl- transferase (mtr) and a proton-motive electron transport chain with cy- tochromes, couple methanogenesis to a proton and a sodium ion gradient at the same time [ ]. . atp synthases from archaea despite all the differences in how the electrochemical ion potential to drive atp synthesis is generated, all archaea have an atp synthase. the enzyme catalyzes atp synthesis according to eq. ( ), at the expense of the transmembrane electrical ion gradient [ , ]: adp þ pi þ n ionsout↔atp þ n ionsin: ð Þ since the bioenergetics of archaea has such a wide variety of differ- ent mechanisms it was thought that the atp synthases of archaea are different in different tribes! the activity of atp synthases is rather easy to analyze. atp hydrolysis can be measured by phosphate release from atp or atp synthesis can be studied by artificial ph jumps in whole cells [ ]. thus, the presence of the enzyme was demonstrated rather early in time. the nature of the enzyme was then addressed by attempts to purify it from different sources. interestingly, despite all the attempts in the – s, there was no clear picture on the subunit composition of the archaeal atp synthases. all enzyme prepara- tions varied in polypeptide compositions and the idea arose, that atp synthases from archaea differ in subunit composition and thus in struc- ture and function. genes had been isolated, but only single genes, not the entire collection that encodes the a ao atp synthase. this is due to the fact that genes had been isolated from crenachaeota in which, as determined later by genome sequencing, the genes are spread over the genome [ ]. in contrast, the euryarchaeon methanosarcina mazei gö contained all genes in a cluster, actually in an operon, and this allowed for the first time a proposal on the subunit composition and topology in a ao atp synthases [ ]. these data indicate that the en- zyme contains at least nine subunits. this was (much later) confirmed after the first “complete” enzymes had been isolated [ ]. early electron micrographs revealed that the a ao atp synthase is, like the f fo atp synthase and the v vo atp synthase, organized in two domains that are connected by stalks [ ]. at the time of discovery of archaeal atp synthases two classes of atp synthases/atpases were known. the f fo atp synthases present in bacteria, mitochondria and chloroplasts were evolved to synthesize atp. on the other hand, organelles of eukaryotes need to be energized to drive, for example, transport processes. since electron transport machineries are only found in mitochondria or chloroplasts, the other organelles are energized by atp that is hydrolyzed according to eq. ( ). the atpase that catalyzes this reaction was purified from those organelles and shown to have the same overall domain topology, with membrane domain and a cytoplasmic domain that are connected by stalks. some of the subunits of the globular cytoplasmic domain of v vo atpases and f fo atp synthases like α/b or β/a shared a consider- able sequence identity ( – %), whereas other smaller subunits did not. therefore, it was concluded that atp synthases/atpases arose from a common ancestor but evolved into different classes with distinct function (atp synthesis vs. atp hydrolysis) [ , – ]. since the first organellar atpases were purified from vacuoles, this class of enzymes is now referred to as vacuolar v vo atpases. it should be pointed out that eukaryotes thus have two different atpases/atp synthases: a f fo atp synthase in mitochondria and chloroplasts and a v vo atpase in other organelles. for a long time, there was a clear view on the “atp synthase/atpase world” that had two “continents”, the f fo atp syn- thase and the v vo atpase. g. grüber et al. / biochimica et biophysica acta ( ) – after the first biochemical, immunological and molecular studies re- searchers were puzzled to group the archaeal enzymes. they apparently had properties of enzymes from both classes. sequence analysis revealed a close relationship of the a and b subunits to a and b of v vo atpases, respectively [ ]. since the primary sequence identity of a and b was higher to a and b from v vo atpase than β#α from f fo atp synthase, the archaeal enzyme was named v vo atpase and genes were annotated as genes encoding v vo atpase subunits. however, already at that time, mukohata and schäfer [ , ] argued that, although the archaeal atp synthase shares features with both, v vo atpase and f fo atp synthase the enzyme is so different from the other two groups, that they should be grouped in a third class, the archaeal or a ao atp synthase. this is now clearly justified by the structural and mechanistic results, as discussed below, and functional studies. whereas the f fo atp synthase catalyzes atp synthesis at the expense of an electrochemical ion gradient, the eukaryal v vo atpase functions as an atp-driven ion pump, unable to synthesize atp under physiological conditions. the cellular function of archaeal atp synthase and f fo atp synthase is to synthesize atp by ion gradient-driven phosphorylation, but the reaction is reversible and they may also work as an atp-driven ion pumps to generate an ion gradient under fermentative conditions. . structure and catalytic mechanism of the a ao atp synthase . . the overall arrangement of the a ao atp synthase the a ao atp synthase is composed of subunits a–f, h, a and c in the proposed stoichiometry of a :b :c:d:e :f:h :a:cx. similar to the related bacterial f fo atp synthase (α :β :γ:δ:ε:a:b :cx) it possesses a water- soluble a domain, containing the catalytic sites, and an integral mem- brane ao domain, involved in ion translocation (fig. a). two dimensional- [ , ] and three dimensional reconstructions [ – ] of electron micrographs revealed a bipartite structure, fig. . (a–d) arrangements of the atomic structures of a ao atp synthase subunits inside th (orange) and b (dark green) from enterococcus hirae (pdb id: vr [ ]) alternate in the a b structure of subunit c (pdb id: r z [ ]; blue) and d (pdb id: aon [ ]; purple) form the the c ring (wheat) from pdb id: bl [ ]. the thermus thermophilus eh dimer (green and c (b), whereas the crystal structure of pyrococcus horikoshii ot subunit e (pdb id: dt [ ]; been proposed [ ] that ion-translocation in the interface of the c ring and the c-terminal mem which are transferred to the barbelled-shaped n-terminal domain of subunit a (yellow) and sub to switch from a more extended (d) into a curved conformation (a) and vice versa, providing the for clarity the em map is not shown in figures b and c, while in figure d one of the peripheral consisting of a and ao domains, which form a pair of coupled rotary motors connected with one central and two peripheral stalks. the soluble a domain has the catalytic activity and the hydrophobic membrane-embedded ao domain is responsible for ion translocation across the membrane. a collar-like structure located perpendicular to the membrane seems to anchor the two peripheral stalks, which are not penetrating into the ao domain. both peripheral stalks go all the way up to the top of the a b headpiece, thereby connecting statically and mechanistically the a with the ao sector via the collar-like domain. . . high resolution structures of the nucleotide binding subunits a and b the a sector (a atpase) consists of the subunits a, b, c, d and f in the stoichiometry of a :b :c:d:f and is able to catalyze atp hydrolysis [ ]. in the last decade all individual subunits of the a atpase have been solved at high resolution [ – ]. firstly, low resolution structures of the a sector [ , ] and the entire a ao atp synthase [ – ], combined with cross-linking data [ , ], and later crystallographic structures of the a :b - [ ] and a :b :d:f-complex [ ] enabled the assignment into the enzyme complex shown in fig. a–c. the headpiece of a consists of the subunits a and b, alternating around the periphery of a central cavity, which is made up by subunit d. this central subunit penetrates inside this cavity and is in proximity to an a-b-a triplet [ , – ], thereby coupling ion-translocation in the a–c interface of ao with catalytic events in the atp synthesizing inter- face of subunits a–b. subunit a has been regarded as having catalytic function, while subunit b plays an important role in nucleotide binding and/or regulatory function [ , ]. crystallographic structures of the nucleotide-binding subunits a [ , , ] and b [ , , ] of a ao atp synthases show that they are composed of an n-terminal β-barrel, an α–β central domain, and a c-terminal α-helical bundle, similar to the homologue nucleotide-binding subunits α and β of f fo atp synthases [ ]. however, the superimposition of the two catalytic subunits of a and β of a ao atp synthases and f fo atp synthases, respectively, e em map of archaeon pyrococcus furiosus (em database id: emd [ ]). subunits a hexamer. the nmr structure of subunit f (pdb id: ov [ ]; magenta) and the crystal central stalk. the structure of subunit a (yellow) was taken from pdb id: rrk [ ] and yan) was taken from pdb id: k b [ ] and reveals the almost straight peripheral stalk red) and the t. thermophilus structure form the kinked second peripheral stalk (c). it has brane-embedded domain of subunit a (yellow cylinder) causes alterations in the ao sector, unit c. as one consequence, the subunit a alterations will force the peripheral stalk subunits storage of transient elastic energy during ion-pumping and atp synthesis/-hydrolysis (d). stalk subunits is removed. fig. . (a) structure comparison of the bovine β subunit (yellow; pdb id: bmf [ ]) and the amp–pnp bound subunit a structure (orange; pdb id: i l [ ]). subunit a has two distinct structural features compared to β subunit which are highlighted in brown color; the non-homologues region (nhr from to ) and the c-terminal two helix extension from to residues. the difference in the binding of the amp–pnp molecules could also be clearly noted. (b) structure comparison of vanadate (avi, cyan; pdb id: p [ ]), sulfate (as, yellow; pdb id: i [ ]) and amp–pnp (apnp, orange; pdb id: i l [ ]) bound structures of subunit a. the sheet-loop-helix motif of the p-loop is shown in cartoon representation. the various modes of interaction of the bound sulfate, vanadate and amp–pnp molecules to the s residues in the as, avi and apnp structures are shown. the crucial water molecules are shown in sphere representation. the water molecule from the as structure is marked as w and the one from apnp is marked as w . the sulfate (yellow stick) bound structure (as) is assumed to be in a substrate-binding-like state, the vanadate- (v , cyan stick) bound structure (avi) is proposed to take a transition like state, and the amp–pnp- (orange stick) bound structure (apnp) the product-bound state. the s residue plays an important role by way of interacting with the ligand molecules in different modes in all states. the substrate-binding-like state and the product-release state are hydrated while the transition-like state is deprived of water molecules in the active site. the distances between the closest oxygen atom of the sulfate, vanadate and γ-phosphate of the amp–pnp molecules to the ger-loop residues e and r for the as, avi and apnp structures are also indicated. the second vanadate (v , cyan stick) is also shown which demonstrates the pathway of entry of the substrate molecule. g. grüber et al. / biochimica et biophysica acta ( ) – shows differences in the subunits with the additional α-helices at the very c-terminus of subunit a and the so-called non-homologous region (nhr), of about amino acids near the n-terminus [ ] (fig. a), which are not present in β subunits of f fo atp synthases, but present in subunit a of the related eukaryotic v vo atpases [ , ]. in comparison, as shown in the crystal structure of the m. mazei gö a ao atp synthase b subunit [ ], the peptides g to p of the n-terminus of subunit b forms a β-sheet-loop structure, and is homolo- gous to the actin-binding motif of subunit b of the human v vo atpase. whether the a headpiece is linked with the actin network via subunit b, as described for the v vo atpase [ ], has to be resolved. . . critical residues in the p-loop of the catalytic a subunit recently, the structure of the catalytic subunit a of the pyrococcus horikoshii ot a ao atp synthase of the sulfate (as), adp (aadp) and amp–pnp (apnp) bound forms has been determined [ ]. the results demonstrated that the phosphate binding loop (p-loop) residue serine is highly important for the interaction with the nucleotides and the inorganic phosphate (fig. b). reflected also by the diverse p-loop sequence, the crystallographic structures indicated that subunit a has a unique arched conformation for the p-loop region, due to which the mode of binding of the nucleotide is different from that of the catalytic β-subunit of f fo atp synthases. the second unique p-loop residue in subunit a, phenylalanine, stabilizes this arched loop (fig. b) and is there- fore one of the critical residues in the p-loop sequence (gpfgsgkt) of subunit a. this phenylalanine residue is the equivalent amino acid to the alanine in subunit β of f fo atp synthases (ggagvgkt), which is a key residue in the catalytic process inside the β subunit that moves towards the γ-phosphate of atp during catalysis [ ]. the different amino acid composition in the p-loop of subunit β of f fo atp synthases is also reflected by its horizontal orientation. the novel p-loop conformation in subunit a forces the nucleotide into a different arrangement inside the catalytic site with weaker interactions of different and/or homologous surrounding amino acid residues and making the nucleotide more solvent exposed [ ]. this structural feature explains the ability of a ao atp synthases to hydrolyze apart from atp also gtp and utp with % and % activities, respectively [ , ]. these structural designs demonstrate how nature optimizes biological activities down to such tiny details. the importance of the polar serine residue of the p-loop in subunit a is also indicated in the recently determined structures of the sulfate as [ ] and transition-like state, vanadate-bound form of catalytic subunit a (avi) of the a ao atp synthase from p. horikoshii ot [ ] (fig. b). in both structures the sulfate or vanadate interacts only with s in the p-loop. however, the mode of interaction is very different; while in as it is through a water molecule, in avi it is a direct hydrogen bonding interaction. a comparison of the avi, as and amp–pnp (apnp) bound structures showed that the vanadate molecule is positioned closer to the p-loop compared to the sulfate molecule, and that the γ-phosphate is placed even closer in the apnp structure, indicating that vanadate is situated in the intermediate position. by analogy with vanadate-bound structures of the biological motors f fo atp synthase and myosin [ , ] it could be interpreted that the image of fig.� g. grüber et al. / biochimica et biophysica acta ( ) – vanadate-bound state mimics a transition-like state, with the sulfate- (a phosphate mimic) bound structure (as) taking the substrate-like position and the amp–pnp-bound structure (apnp) adopting the product-bound state during catalysis (fig. b). structural rearrangement of catalytically important residues in the so-called walker b motif of subunit a became obvious, when the avi, as and apnp bound structures have been compared (fig. b, [ ]). the walker b motif residues or ger-loop, which is located above the p-loop (walker a motif) and known to be involved in immobilization and polarization of a water molecule to facilitate nucleophilic attack at the γ-phosphate of atp, is deviated by around . Å in the avi structure when compared with the as structure. further, the side chains of gluta- mate (e ) and arginine (r ) residues are significantly deviated by . Å and . Å, respectively, moving closer to the vanadate molecule (fig. b) and revealing substantial structural rearrangement during the catalytic event. the avi structure of the a ao atp synthase showed for the first time the entry of the substrate sulfate, a phosphate analogue, molecule into a catalytic subunit of an atp synthase (fig. b). a second vanadate mole- cule is found to be positioned, where the atp molecule transiently fig. . (a) structure of subunit b from m. mazei gö (dark green) showing the different transiti a ao atp synthase with subunits d (pdb id: aon [ ]; yellow) and f (pdb id: ov [ ]; m shown as surface representation. the atp molecule enters via the gap formed by subunits a an subunit b rotates and allows the atp molecule to penetrate into the hexamer in concert with th the rotation of d moves the nucleotide towards the transient (t ), which is placed near to th associates in the b subunit structure [ ], demonstrating a similar path- way of entry for both subunits in a ao atp synthases. this position also confirms the recent finding that during atp synthesis the inorganic phosphate binds first and hinders atp binding to the catalytic site, which then selectively allows binding of adp [ ]. . . how the nucleotide enters into the binding pocket the crystal structures of the nucleotide bound subunit b of the a ao atp synthase from m. mazei gö showed for the first time in atp synthases, how the atp traverses the protein surface via two transient intermediate binding sites to its final binding pocket and the concomi- tant rearrangements in the nucleotide-binding and c-terminal region of subunit b (figs. a–b) [ , , ]. when the nucleotide enters close to the c-terminal domain of b, subunit d moves slightly, paving way for it to interact with subunit b (transition state in fig. b), which makes the c-terminal domain rotate by °. this moves the nucleotide inside the a b hexamer, close to p-loop of subunit b (transition state ), a position which compares well with the binding site of the an- tibiotic, efrapeptin c in the β subunit of f fo atp synthases. efrapeptin c on sites of the atp molecule (blue stick). (b) cross sectional view of the hexamer model of agenta). subunits b (dark green; pdb id: c [ ]) and a (orange; pdb id: i l [ ]) are d b into the hexamer and positions in transient (t ), whereby the c-terminal domain of e rotation of subunit d. a concerted movement of the c-termini of subunits b and f as well e p-loop, followed by the movement of atp to the final binding site (f). image of fig.� g. grüber et al. / biochimica et biophysica acta ( ) – is a potent inhibitor of f fo atp synthases in mitochondria and some bacterial species [ ]. due to the rotational movement of the central stalk subunit d, the nucleotide will be moved to the actual binding site of subunit b [ ]. . . the central stalk couples ion-translocation and atp synthesis the shape of the a domain had shown that the a b hexamer and the ao sector are separated by a Å long central stalk, consisting of the subunits c, d and f, with subunit c forming the bottom of the central stalk [ , ]. as shown by the crystallographic structure of the entero- coccus hirae subunit d, this protein comprises a long left-handed coiled coil structure with a unique short β-hairpin [ , ]. such left handed coiled-coil structure is also conserved in the rotary proteins fiij of the flagellar type iii protein export apparatus [ ] and subunit γ of f fo atp synthases [ ]. in contrast, the β-hairpin region of subunit d is specific for this subunit and important for atpase activity in a ao atp synthases [ ]. subunit d can be cross-linked to subunit a in a nucleotide-dependent manner [ ]. the interaction between both subunits involves both n- and c-terminal segments of d. similarly, in m. mazei gö a ao atp synthase, subunit f can be cross- linked to subunit b through their c-terminal sequences, which shows a nucleotide-dependent behavior [ ]. the high resolution structure of b subunit revealed [ ] that the c-terminal peptide of b is at a similar position to the so-called delseed-region of the nucleotide-binding sub- unit β of the f fo atp synthases [ ], which also form a disulphide bond with the c-terminal helix of the coupling subunit γ. subunit f in solution exhibits a distinct two-domain structure, with the n-terminal globular region having residues and the residues – forming the flexible c-terminal part [ ]. the flexible c-terminal tail enables this subunit to undergo up and down movements relative to subunit b, bringing both termini in close proximity (fig. b). the df- [ ] and a b df-crystal structures [ ] of the e. hirae enzyme show that the four-stranded β- sheet in the n-terminal part of subunit f mediates the interaction with subunit d, forming together the rotor shaft. the recently postulated model of the rotation mechanism in the e. hirae a b df-crystal struc- tures [ ] reveal that the df-assembly induces a switch from a bindable form to the nucleotide-bound form in one ab-pair, while the df interac- tion with a second subunit ab-pair causes the alteration from a bound form to a tight nucleotide-binding form [ ]. the rotational dynamics of the e. hirae a b df-complex have recently been confirmed in single molecule studies [ ], showing that df rotates unidirectional in a coun- terclockwise direction during atp hydrolysis with a maximal rotation rate of about ± revolutions/s. in contrast to the thermophilic bacil- lus ps f atpase, which shows three ° steps, which can be further divided into substeps, the e. hirae a b df-complex revealed only three pauses separated by ° [ ], indicating the distinct difference be- tween both molecular motors. the tip of the central stalk in a ao atp synthases is made-up by sub- unit c, which has a funnel shaped structure [ ] with a central cavity, providing space for the d and f assembly (fig. b). as revealed by the . Å resolution structure of the thermus thermophilus enzyme, subunit c sits asymmetrically on the c ring without penetrating significantly in to the central pore of the c ring [ ]. the function of subunit c, which is characteristic for a ao atp synthases, has been described of being a spacer unit that plays a role in coupling and rotational steps [ ]. . . the peripheral stalks and its elastic features the peripheral stalks are made up by the subunits e and h (fig. a–c). concerning their sequence and subunit composition the peripheral stalks of a ao atp synthases are the most divergent elements compared to their related f fo atp synthases or eukaryotic v vo atpases [ ]. as shown by the crystallographic structure of subunit h of the t. thermophilus a ao atp synthase [ ] this protein is entirely α-helical with a long n-terminal helix and a shorter c-terminal helix, which are linked by a sharp kink (fig. a–d). this c-terminal helix is close to the n-terminal helix and the c-terminal tail of subunit e. the kink of subunit h together with the loop of subunit e are predicted to be two flexible joints that tether the headgroup to the coiled-coil region formed by the n-terminal helices of subunits e and h. subunit e is a long, two domain protein with a c-terminal globular domain [ – ], which is in close proximity to the top of an a–b inter- face and c-terminus of h (fig. a), and an extended n-terminal α-helix. structures of a straight- (t. thermophilus, [ ]) and a s-shaped confor- mation (p. horikoshii ot , [ ]) of the extended n-terminal α-helix subunit e have been determined, which fit well into the asymmetric peripheral stalks of the d reconstruction of the p. furiosus enzyme [ ] (fig. b–c). these features support the model in which the switch from a straight- to an s-shaped conformation of subunit e in the two peripheral stalks facilitates elastic power transmission between the ao and a part, which is essential for facilitating the cooperation of the ao and a motors and to increase the kinetic efficiency of the a ao atp synthase engine [ , ]. furthermore, it has been proposed [ ] that ion-translocation in the interface of the c ring and the c-terminal membrane-embedded domain of subunit a causes alterations in the ao sector (fig. a, d), which are transferred to the barbell-shaped n-terminal domain of subunit a and subunit c. as a consequence, the subunit a alterations will force the peripheral stalk subunits to switch from a more extended (fig. a, subunit e (green)) into a curved confor- mation (fig. a, subunit e (red)) and vice versa, providing the storage of transient elastic energy during ion-pumping and atp synthesis/- hydrolysis. . . architecture of the membrane-embedded ao domain the two peripheral stalks of a ao atp synthases, which have no membrane-spanning n-terminal helix like the one in f fo atp synthases, are linked to the globular domain of subunit a, whose c- terminal membrane-integrated segment forms the ion channel together with the c ring [ , ]. the a ao atp synthase subunit a (about kda) is similar to its related subunit a in eukaryotic v vo atpases and is par- tially functionally similar to subunit a (about kda) of f fo atp synthases [ ]. its c-terminal and ion-translocating part is membrane- integral and its n-terminal domain (about kda) is on the cytoplasmic side. the crystallographic structure of the barbell-shaped n-terminal domain of the meiothermus ruber a ao atp synthase has been deter- mined [ ], (fig. a–c). the middle and helical bundle of subunit a faces the wedge-like subunit c. the hydrophobic c-terminus of a is pre- dicted to have – transmembrane helices and is known to be involved in ion translocation [ ]. these α-helices are in close contact to a ring made by multiple copies of subunit c, the rotor subunit. subunit a is sug- gested to form two “ion channels” to load the c ring with coupling ions over the first channel and to remove the ion again from the c ring over the second ion channel [ ]. the recently determined -dimensional re- construction of the t. thermophilus complex shows the eight transmem- brane helices in subunit a [ ]. these helices divide into two bundles, each containing four helices (fig. a). one bundle appears almost per- pendicular to the membrane and contacts a single c subunit near the middle of the membrane. the other bundle appears tilted and contacts the adjacent c subunit closer to the periplasm. this arrangement brings the two c subunits in distinct chemical environments and establishes the conditions necessary for a two half-channel model of proton translocation [ ]. whereas subunit a has underwent little changes during evolution, subunit c has been a large evolutionary playground [ ]. a lot of archaea have an kda c subunit with two transmembrane α-helices [ , – ], but some archaea have very unusual c subunits. a kda c subunit with four transmembrane α-helices is present in all species of pyrococcus, thermococcus, methanobrevibacter, methanobacterium, desulfurococcus, staphylothermus and in ignisphaera aggregans [ ] as well as in methanothermobacter thermautotrophicus [ ] and methanosphaera g. grüber et al. / biochimica et biophysica acta ( ) – stadtmanae [ , ]. methanocaldococcus jannaschii and methanococcus maripaludis have a triplicated c subunit (a c subunit with three hairpins and six transmembrane helices) with a molecular mass of around kda [ ]. also methanopyrus kandleri is very special, because it is the only organism known so far, which has a c ring consisting of only one c subunit with hairpins and therefore ion-binding sites [ , ]. although the variation in size is already unique, even more impor- tant, also for function, is the variation in number of ion binding sites image of fig.� g. grüber et al. / biochimica et biophysica acta ( ) – per c subunit. in bacterial f fo atp synthases, the c ring is made by mul- tiple copies ( – ) of one subunit [ ]. the kda c subunit with four transmembrane α-helices of e.g. pyrococci and thermococci lost one ion binding site [ ] and the triplicated c subunit from m. jannaschii [ ] and m. maripaludis also lost one. this has enormous consequences for the function of the enzyme. if we consider c rings to have the same number of transmembrane α-helices, the c rings from pyrococci and thermococci have only half the number of ion binding sites per atp syn- thesizing units. according to: Δgp ¼ −n � f � Δeμion ð Þ where Δgp = phosphorylation potential, n = number of translocated ions, f = faraday constant, and Δeμion = electrochemical potential of the coupling ion (na+ or h+), the loss of one ion binding site in every sec- ond hairpin of the rotor would lower the number of ions by half. the resulting value for “n” (ions/atp) of two is not enough to generate a phos- phorylation potential of ~ to kj/mol and thus the enzyme is no lon- ger able to pump ions against this potential and thus unable to synthesize atp. since the a ao atp synthases from pyrococci and thermococci are the only atp synthases encoded in the genome [ ], they must synthesize atp at the expense of Δeμion in vivo. a solution to this enigma is a c ring that has more c subunits and indeed, circumstantial evidence point to a c ring in p. furiosus [ ]. . ion translocation and -specificity of the c ring of a ao atp synthases the c ring is the ion carrier and the primary structure of the c ring de- termines which ion binds to the c ring. c rings from most archaea and bacteria are proton selective and the proton binding site is the con- served carboxylate (glu, asp) present in helix two of the kda c subunit [ ]. the h+ is bound between the carboxyl oxygen of the conserved carboxylate and the main chain carbonyl of another amino acid, for ex- ample phenylalanine [ ]. very few c subunits, notably from anaerobic bacteria and archaea use na+ instead of h+ [ , ]. the na+ binding site of e.g. ilyobacter tartaricus contains the before mentioned carboxyl- ate and three more amino acid residues that coordinate the na+ [ , ]. these are: q , v and s . y forms a hydrogen bond with e and stabilizes the geometry of the ion coordination shell, but is not directly involved in na+ coordination. t itself is also not directly involved in na+ binding but coordinates a buried structural water molecule in the na+ binding site (fig. b (inset)). of these residues, only three are ade- quately conserved to be spotted by sequence comparisons. these are q , e and s . q is substituted and functionally conserved by e, and s by t in some species. thus the minimal and sufficient motif for na+ binding is q/e…e t/s. this motif is also present in the a ao atp synthase of some archaea (see below) as well as e. hirae. in the a ao atp synthase c ring of e. hirae (also called “bacterial v vo atpase”) a similar na+ binding site is observed with the essential carboxylate e as well as q , l , t and q , which form the ion coordina- tion shell and y which makes hydrogen bonding interaction with e (fig. c (inset)). as pointed out above, due to the variation in the number of protomers the diameters of these c ring rotors differ from organism to organism. a significant structural difference between c rings of f fo and a ao atp synthases is represented by the comparison of the na +- translocating undecameric ring of i. tartaricus c ring (f fo atp synthase) and the c ring of the e. hirae a ao atp synthase (fig. ). whereas the i. fig. . (a) the three-dimensional em map of the t. thermophilus enzyme at . Å resolution (em ring (wheat) and subunit a (yellow) are shown as solid surface. two cross-sections of the map s subunit at two positions (indicated by red arrows). (b) structure of the c ring of the f fo atp syn glass shaped complex. (inset) sodium ion binding site with the ion coordination shell formed b ometry. (c) the a ao atp synthase c ring structure from e. hirae (pdb id: bl [ ]) revealing shaped c subunit (left; pdb id: r z [ ]; blue). (inset) sodium ion binding site of the e. hirae c q and y having hydrogen bonding interaction with e . tartaricus c ring forms a cylindrical, hourglass shaped protein complex with an outer diameter of ~ Å and an inner diameter of ~ Å [ ], the decameric ring of e. hirae is much more wider spanning an external diameter of Å and an inner diameter of Å [ ]. although among all the solved c ring structures, the e. hirae c ring has only protomers, the external c ring diameter is wider than the one of f fo atp synthase c rings. this structural feature enables the funnel shaped subunit c of a ao atp synthase, which is not present in f fo atp synthases, to pen- etrate into the central cavity of the c ring [ ], and allowing a direct translation event between c ring rotation and atp synthesis in the a b headpiece (fig. b). a sequence comparison of all the sequences available for c subunits (as of sept. ., ) revealed the na+ binding motif q/e…e t/s to be present in all methanogens and halobacteria, as well as in species of the genera pyrococcus, thermococcus, desulfurococcus, ignisphaera, staphylothermus and nanoarchaeum (table ). of these, the a ao atp synthases from methanobrevibacter ruminantium and p. furiosus have been shown to be na+ specific [ , , ]. structural models of a c ring of p. furiosus and a c construct of m. ruminantium, generated com- putationally, revealed the nature of the na+ binding sites (fig. ) [ ]. the c ring and the c construct consist of c subunits with four trans- membrane helices each. in the c ring of p. furiosus the na + binding site is within one c subunit flanked by transmembrane helix (tm ) and helix (tm ). the na+ is coordinated by e (tm ), q (tm ), t (tm ), and q (tm ), and by the backbone of l (tm ). y (tm ) is not directly involved in na+ coordination, but forms a hydrogen-bond with e , and therefore stabilizes the geome- try of the ion-coordination shell (fig. a). this kind of network is iden- tical to that revealed by the crystal structure of the c rotor from e. hirae [ ]. between two c subunits is no second ion binding site in the c ring of p. furiosus (fig. b). there the essential glutamate of the na+ binding site was replaced by a methionine (m ) during evolution and there- fore nature designed an unusual c ring with only one na+ binding site in one c subunit. this is different in the c ring of m. ruminantium. as was evident from sequence comparisons and confirmed by modeling studies using a c construct, m. ruminantium has one na + binding site within one c subunit (fig. c), as in p. furiosus, but also a second na+ binding site between two c subunits (fig. d). both na+ binding sites are completely identical in their amino acid composition. within one c subunit the na+ is coordinated by the side chains of the amino acids e (tm ), q (tm ), q (tm ) t (tm ) and l (tm ). again y (tm ) is for hydrogen-bonding with the side chain of e . the second na+ binding site in the c ring of m. ruminantium is between two c subunits. again e (tm ′), q (tm ′), q (tm ), t (tm ) and l (tm ) are directly involved in na+ coordination. y (tm ) stabilizes the geometry of the ion-coordination shell by hydrogen-bonding with e [ ]. therefore nature designed in the case of m. ruminantium a c ring, which has one na+ binding site within and another between each c subunit. . adaptations of archaeal atp synthases to the inhospitable environments their hosts thrive in sodium bioenergetics is advantageous for organisms that live on the thermodynamic edge of life [ ] like methanogens or t. onnurineus thriving on formate. any reduction in the magnitude of the electro- chemical ion potential across the membrane by leakage of ions back into the cell would be detrimental. biological membranes are leakier for protons than for sodium ions [ ]. thus, a sodium bioenergetics is database id: emd [ ]) is shown as gray surface. the density corresponding to the c egments near the middle of the c-ring show the contacts of c subunits with helices of the a thase from ilyobacter tartaricus (pdb id: yce [ ]) showing a narrower cylindrical, hour- y e , q , v and s and y is making a hydrogen bond with e to stabilize the ge- a wider diameter at the upper part of the cylinder, which could accommodate the funnel ring showing the na+ coordination shell formed by amino acids e , q , l , t and g. grüber et al. / biochimica et biophysica acta ( ) – seen as the primary event in the evolution of bioenergetics [ , , ]. indeed, an acetogen with an ancient pathway in which carbon dioxide fixation is coupled to atp synthesis by a chemiosmotic mechanism re- table ion binding motifs of different archaeal and bacterial c subunits. organism bacteria (c subunits with one hairpin) d acetobacterium woodii c /c ilyobacter tartaricus propionigenium modestum bacillus subtilis escherichia coli bacteria (c subunits with two hairpins) enterococcus hirae e a h -h h -h euryarchaeota (c subunits with one hairpin) f archaeoglobus fulgidus ferroglobus placidus haladaptatus paucihalophilus halalkalicoccus jeotgali haloarcula hispanica halobacterium salinarum haloferax volcanii halogeometricum borinquense halopiger xanaduensis haloquadratum walsbyi halorhabdus utahensis halorubrum lacusprofundi haloterrigena turkmenica methanocella paludicola methanococcoides burtonii methanocorpusculum labreanum methanoculleus marisnigri methanohalobium evestigatum methanohalophilus mahii methanomethylovorans hollandica methanoplanus petrolearius methanoregula boonei methanosaeta concilii methanosalsum zhilinae methanosarcina acetivorans methanosphaerula palustris methanothermus fervidus natrialba magadii natronococcus occultus natronomonas pharaonis natronorubrum tibetense picrophilus torridus thermoplasma acidophilum euryarchaeota (c subunits with two hairpins) methanobacterium sp. al- g a h -h h -h methanobrevibacter ruminantium g h -h h -h methanosphaera stadtmanae g h -h h -h methanothermobacter thermautotrophicus g h -h h -h pyrococcus furiosus e h -h h -h thermococcus onnurineus e h -h h -h lies on a sodium potential. this pathway allows for the synthesis of only a fraction of an atp [ ]. the same is true for methanogens that em- ploy pretty much the same pathway [ ]. so far, sodium bioenergetics has site b site b ion c q vxettxxy na + q vxestxxy na + q ixestxxy na + n lxealxxi h + i lxdaixxi h + v lxgtqxxy -- q mxetyxxl na + e ixetixxf na + e ixetixxf na + e lxetlxxl na + e lxetlxxl na + e lxetlxxl na + e lxetlxxl na + e lxetlxxl na + e lxetlxxl na + e lxetlxxl na + e lxetixxl na + e lxetlxxl na + e lxetixxl na + e lxetlxxl na + q ixetlxxl na + e ixetixxf na + e lxetvxxf na + e ixetixxf na + e ixetixxf na + e ixetixxf na + e ixetixxf na + q ixetvxxf na + e ixetixxf na + e lxetlxxf na + q ixeaixxf h + e ixetixxf na + /h + e ixetixxf na + q lxethxxf na + e lxetlxxl na + e lxetlxxf na + e lxetlxxl na + e lxetlxxl na + q ixetlxxi na + q ixetlxxi na + q lxetqxxy na + q lxetqxxy na + q lxetqxxy na + q lxetqxxy na + q ixetqxxy na + q ixetqxxy na + q lxetqxxy na + q lxetqxxy na + v lxmtqxxy -- q mxetmxxf na + v lxmtqxxy -- q mxetmxxf na + (continued on next page) euryarchaeota (c subunits with three hairpins) h methanocaldococcus jannaschii a h -h a lxqtqxxy -- h -h q lxetqxxy na + h -h q mxetfxxf na + methanococcus maripaludis h -h a lxqtqxxy -- h -h q lxetqxxy na + h -h q mxetfxxf na + methanospirillum hungatei h -h v ixqtqxxy -- h -h q vxetqxxy na + h -h q mxetfxxf na + methanothermococcus okinawensis h -h a lxqtqxxy -- h -h q lxetqxxy na + h -h q mxetfxxf na + methanotorris igneus h -h a lxqtqxxy -- h -h q lxetqxxy na + h -h q mxetfxxf na + euryarchaeota (c subunits with hairpins) methanopyrus kandleri i q fxetqxxy na + crenarchaeota (c subunits with one hairpin) f acidianus hospitalis v ixegixxy h + acidilobus saccharovorans v lxegixxy h + aeropyrum pernix v lxegixxy h + caldisphaera lagunensis v lxegixxy h + caldivirga maquilingensis m fxetixxy h + hyperthermus butylicus l lxegixxy h + ignicoccus hospitalis l ixetpxxy h + metallosphaera sedula v ixegixxy h + pyrobaculum aerophilum v lxeaixxy h + pyrolobus fumarii v lxegixxy h + sulfolobus acidocaldarius v ixegixxy h + thermofilum pendens l lxegixxy h + thermoproteus neutrophilus l lxeavxxy h + thermosphaera aggregans q yxelwxxl h + vulcanisaeta distributa i lxeaixxy h + crenarchaeota (c subunits with two hairpins) g desulfurococcus kamchatkensis a h -h m lxmtqxxy -- h -h q yxelwxxy na + ignisphaera aggregans h -h t fxmtqxxa -- h -h q yxelfxxi na + staphylothermus marinus h -h m lxmtqxxy -- h -h q yxelixxl na + nanoarchaeota (c subunits with one hairpin) f nanoarchaeum equitans q lxetqxxy na + korarchaeota (c subunits with one hairpin) f korarchaeum cryptofilum l lxegvxxy h + thaumarchaeota (c subunits with one hairpin) f cenarchaeum symbiosum l mxesixxy h + nitrosopumilus maritimus l mxesixxy h + nitrosoarchaeum limnia l mxesixxy h + nitrososphaera gargensis l mxesixxy h + organism site b site b ion c table (continued) a h = helix , h = helix , h = helix , h = helix , h = helix , h = helix . b site and describes amino acids of the h+ or na+ binding motif in helix one and two of the hairpin-like c subunit. c except were indicated (●, experimental evidence), the ion specificity is suggested based on the presence or absence of the na+ binding motif. d in bacterial c subunits, the ion binding site is between two c subunits and built by q (site ) and et (site ). e in these c subunits, the na+ binding motif is shared by h –h and h –h . there is only one na+ binding site in four transmembrane helices. f as in bacterial c subunits, the ion binding site is between two c subunits and built by q (site ) and et (site ). g these c subunits have two ion binding sites in four transmembrane helices. one is within one c subunit, one inbetween two c subunits. h in these c subunits, the na+ binding motif is shared by h –h , h –h and h –h . there are two na+ binding sites in six transmembrane helices. i this c subunit has thirteen covalently linked hairpins, each has the depicted na+ binding site. g. grüber et al. / biochimica et biophysica acta ( ) – only been observed in anaerobes. in addition to living in low energy envi- ronments these environments are full of fermentation end products such as short chain fatty acids. these act as proton ferries to decouple metabo- lism from atp synthesis. these fermentation end products cannot shuffle back na+ into the cell and thus, a na+ potential is not dissipated by short chain fatty acids [ ]. a na+-dependent a ao atp synthase is fully consistent with the phys- iology of m. ruminantium. it has no cytochromes and only the na+- fig. . (a) computationally derived structural model of the na+ binding site of the c ring from p. furiosus. the ion binding site is within one c subunit between tm and tm . the na+ is coordinated by e (tm ), q (tm ), t (tm ), and q (tm ), and by the backbone of l (tm ). y (tm ) is not directly involved in na+ coordination, but forms a hydrogen- bond with e . (b) between two c subunits is no second ion binding site in the c ring of p. furiosus. there the essential glutamate of the na+ binding site is replaced by a methionine (m ). (c) the c ring of m. ruminantium has two na+ binding sites. according to the computationally derived model [ ] the na+ is coordinated by the side chains of the amino acids e (tm ), q (tm ), q (tm ) t (tm ) and l (tm ) within one c subunit. again y (tm ) is for hydrogen-bonding with the side chain of e . (d) the second na+ binding site in m. ruminantium is between two c subunits. again e (tm ′), q (tm ′), q (tm ), t (tm ) and l (tm ) are directly involved in na+ coordination. y (tm ) stabilizes the geometry of the ion-coordination shell by hydrogen-bonding with e [ ]. g. grüber et al. / biochimica et biophysica acta ( ) – motive methyltransferase for membrane energization and thus, the na+ potential must be used to drive atp synthesis [ , , ]. with the evolution of cytochromes and an additional proton-pumping elec- tron transfer chain in some methanogens like the methanosarcinales, an organism arose that couples its metabolism to the generation of a proton potential and a sodium ion potential. the atp synthase adapted to this scenario by using na+ and h+ [ , ]. apparently, na+ and h+ concurrently drive atp synthesis. the ion binding site has a high prefer- ence for h+, but under physiological conditions of ph . and mm nacl (sea water) both na+ and h+ are used simultaneously [ ]. the minimal na+ binding motif is conserved but the residues involved in na+ binding in bacterial c subunits are less conserved. noteworthy is the change of glutamine (q) of the sodium binding motif q…es/t to a second glutamate, and indeed, this exchange still allows for na+ binding [ ]. such a q → e exchange is present in a lot of methanogens (table ). the ion specificity of the membrane-bound hydrogenase (mbh) of p. furiosus has not been addressed experimentally, but there is no reason to believe that sodium ions are not the coupling ion. it is also notewor- thy, that some of the halophilic archaea have a sodium ion binding site: but whether the atp synthase indeed uses na+ or na+ and h+ has to be established. apart from the euryarchaeota (methanogens, thermococci and pyrococci), only the genera desulfurococcus, ignisphaera and staphylothermus of the phylum crenarchaeota [ ] as well as nanoarchaeum equitans of the phylum nanoarchaeota have the conserved na+ binding site. unfortunately, nothing is known about their physiology but it can be concluded that na+ is important for their physiology. another adaptation is the increase in length of the c subunits with in- creasing temperature. at least in methanogens, there is a clear tendency from one hairpin (most methanogens, e. g. m. mazei, °c) to two hair- pins (m. thermautotrophicus, °c), three hairpins (m. jannaschii, °c) and hairpins (m. kandleri, °c). the higher the number of covalent linkages the higher the stability of the rotating c ring. these arguments may be true for the two peripheral stalks that may gives additional stabil- ity to the rotating nanomachine. . conclusion a ao atp synthases of hyperthermophilic archaea have unique structural and functional features, including an optimized p-loop design of the catalytic a subunit, enabling the enzyme to catalyze atp apart from gtp and utp. the Å long central stalk with its subunits c, d and f, reflects a coupling mechanism diverse to the wankel engine like form, described for the γ–ε stalk ensemble of f fo atp synthase. a hallmark of the classification of a ao atp synthases is the number g. grüber et al. / biochimica et biophysica acta ( ) – and structures of peripheral stalk subunits (e–h). a primary function is to allow the rotary elements of ao and a to move relative to each other. their importance for regulation and fine-tuning of the entire enzyme will be a topic for the near future. so far, biochemical and structural work on these unique enzymes has been done with enzymes isolated directly from cells of these hyperthermophiles. since these are difficult to grow and yields are low, biochemical analyses are a challenge and not possible for many interesting archaea. the advent of genetic systems, overexpression, tagging and affinity purification will bring the field into the next round. there is still lot to do to unravel the beauty of these fascinating enzymes. acknowledgments this work was supported by a grant from the deutsche forschungsgemeinschaft (through sfb , v. müller) and the ministry of education-singapore (moe) (moe -t - - ; arc / ; g. grüber). references [ ] k.o. stetter, history of discovery of the first hyperthermophiles, extremophiles ( ) – . 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( ) - /rf http://refhub.elsevier.com/s - ( ) - /rf atp synthases from archaea: the beauty of a molecular motor . introduction . energy conservation in archaea . atp synthases from archaea . structure and catalytic mechanism of the a ao atp synthase . . the overall arrangement of the a ao atp synthase . . high resolution structures of the nucleotide binding subunits a and b . . critical residues in the p-loop of the catalytic a subunit . . how the nucleotide enters into the binding pocket . . the central stalk couples ion-translocation and atp synthesis . . the peripheral stalks and its elastic features . . architecture of the membrane-embedded ao domain . ion translocation and -specificity of the c ring of a ao atp synthases . adaptations of archaeal atp synthases to the inhospitable environments their hosts thrive in . conclusion acknowledgments references approach of the value of a rent when non-central moments of the capitalization factor are known: an r application with interest rates following normal and beta distributions science & philosophy volume ( ), , pp. - is the golden section a key for understanding beauty? part iii (la sezione aurea è una chiave per la comprensione del bello?) parte iii franco eugeni luca nicotra abstract our goal is to prove that the golden section, however important, is not the only key to understand a mathematical-formalizing approach to the idea of beauty. having developed, from this point of view, reading keys linked to the post- modern, it is necessary to link together the multiple rivulets of knowledge that gather in this direction. moreover the canons of the approaches presented up to now are very indicative for the understanding of many aspects of beauty, which however depends on the historical moment and the cultures created in the various civilizations. therefore we can affirm that there is no effective definition of "beauty" that can be codified through fixed canons, but that the concept is expressed by a series of stratifications and interpretations that tend to link several major variations, expressing the various answers given by man to the question: what is the beauty? keywords: golden section, golden number, beauty, golden rectangle, fractals.  teramo university. full professor of logics and science philosophy,teramo, italy; eugenif @gmail.com.  cultural association “arte e scienza”, president. mechanical engineer and editor in charge of the artescienza magazine, of the bollettino dell’accademia di filosofia delle scienze umane magazine and of the periodico di matematica magazine, rome, italy; luca.nicotra @gmail.com.  received on june th, . accepted on august th, . published on december th, . doi: . /sp.v i . . issn - ; eissn - . ©eugeni and nicotra. this paper is published under the cc-by licence agreement. franco eugeni and luca nicotra sunto nostro obiettivo è provare che la sezione aurea, per quanto di importanza notevole, non è l’unica chiave per comprendere un approccio matematico- formalizzante dell’idea di bellezza. essendosi sviluppate, da questo punto di vista, chiavi di lettura legate al post-moderno, occorre legare tra loro i molteplici rivoli di saperi che si addensano in questa direzione. inoltre i canoni degli approcci fino ad oggi presentati sono molto indicativi per la comprensione di numerosi aspetti della bellezza, che però dipende dal momento storico e dalle culture createsi nelle varie civiltà. pertanto possiamo affermare che non esiste una effettiva definizione del "bello" che possa essere codificata attraverso canoni fissi, ma che il concetto si esprime con una serie di stratificazioni e interpretazioni che tendono a collegare fra loro numerose varianti principali, esprimenti a loro volta le varie risposte date dall’uomo alla domanda: cosa è il bello? parole chiave: sezione aurea, numero aureo, bellezza, rettangolo aureo, frattali. la sezione aurea non basta più! tra bellezza e stupore: matematica e idee molti cultori di quella matematica connessa con la “divina proporzione”coltivano l’idea di un "canone estetico" incentrato appunto sull’idea di regolarità delle forme e quindi, sostanzialmente, di misura. l’idea nasce con luca pacioli nella sua opera de divina proportione. a pacioli fece seguito la scuola neoplatonica/neoplotiniana fiorentina alla quale aderirono personaggi come marsilio ficino e altri, che influenzarono i grandi pittori del tempo (sandro botticelli, raffaello sanzio, michelangelo buonarroti) che della divina proporzione fecero uso continuo nelle loro opere. ma se ben osserviamo le opere prodotte ai tempi del barocco, è facile accorgersi che la bellezza si è allontanata da quell’idea della affannosa ricerca della regolarità, in quanto già da allora si inizia a pensare che il “senso del bello” sia molto di più della regolarità e quindi presente anche in quelle forme ove le non-regolarità non appaiono chiaramente espresse e talvolta addirittura non esprimibili. con l’avvento del post-moderno nascono idee nuove e con esse numerosi oggetti. tali oggetti, oramai tutti codificabili in sequenze binarie e quindi facilmente trasportabili e accessibili via internet, nascono dalle idee trasferite is the golden section a key for understanding beauty? part iii in scritti, dalle immagini, dalle irregolarità, dalla confusione o se si vuole dall’interesse causato da certi prodotti della cultura, siano essi di natura musicale, filmica, poetica o letteraria, specie quando esse tendono a sfuggire sia al controllo degli esperti sia alle analisi di mercato e al controllo della qualità. spesso accade, misteriosamente, che tra due prodotti di uno stesso genere, di qualità press’a poco equivalente, uno sbanca sul mercato, l’altro è destinato a prematura sparizione. tale fenomeno è ben noto come effetto formicaio. spesso è il primo prodotto a essere giudicato bello mentre il secondo non è giudicato tale, indicando una identità, tipica del mondo attuale, tra l’essere bello e l’essere accettato dalla massa. cominciamo, in questo paragrafo, a parlare delle idee, le belle idee che si traducono in fatti concreti. vogliamo, per questo, occuparci in primo luogo, del cosiddetto principio del cassetto (pigeonhole principle) e di qualche sua applicazione. anche se molto semplice, l'uso di questo principio esprime molto bene il modo di ragionare della matematica discreta, traducibile anche in amabili osservazioni salottiere. spesso, per illustrare con una rapida battuta il modo di ragionare della combinatoria, si parla del principio del pecoraio: se vuoi contare le pecore del gregge, conta le zampe e dividi per quattro. la battuta, che esprime una specie di assurdità, è sicuramente di buon effetto, esprime il fatto che si può contare anche in modi impensabili. il nome inglese pigeonhole principle deriva dal fatto che se un certo numero di piccioni vogliono appollaiarsi sopra un certo numero di trespoli (o entrare in certi cassetti) in numero minore dei piccioni stessi, allora almeno su un trespolo ci saranno almeno due piccioni. la validità del principio è dunque ovvia, e nulla deve essere provato. esemplifichiamo. problema - in ogni insieme di o più persone, almeno due compleanni cadono nello stesso mese. se le persone sono i piccioni (in numero di ) e i trespoli sono i mesi (in numero di ) due persone sono nello stesso trespolo-mese! problema - in ogni insieme di o più persone, almeno due sono nate lo stesso giorno. le persone-piccioni sono e i giorni-trespoli sono in un anno. franco eugeni, ezio sciarra, raffaele mascella, matematica ed arte: il senso del bello, in tabularia a.mmx (s.s.quator coronatorum),"academia" editrice d'italia e san marino, . le idee contenute in questo paragrafo e le formule riportate nel paragrafo successivo sono riprese, in forma semplificata, da: franco eugeni, le due rivoluzioni matematiche del secolo: da bourbaki alla matematica del discreto, dedicato dall’autore al padre, prof. carlo eugeni, nel giorno del suo ° compleanno, «periodico di matematiche», serie vi, vol , n , roma, ( ) pp. - . franco eugeni and luca nicotra problema - in ogni insieme di un milione di persone, almeno due hanno lo stesso numero di capelli. basta sapere che ogni persona-piccione ha meno di un milione di capelli. e ora qualcosa di più difficile. problema - in ogni insieme di numeri (distinti) ne esistono almeno due la cui differenza è divisibile per . siccome il resto della divisione di un numero positivo per è un numero tra e , almeno due dei numeri dati hanno io stesso resto. ciascuno di questi due è un multiplo di più un reso eguale per entrambi. segue che la differenza dei due, eliminati i resti è un multiplo di . in formule siano a e b (con a>b) i due numeri che divisi per hanno eguale resto r, allora risulta a= h+r e b= k + r , da cui a – b = (h – k) . molte problematiche di tipo combinatorio possono essere presentate in modo salottiero anche quando la matematica sottogiacente non è semplice. può essere interessante consultare volumi dedicati alla matematica discreta, ove appare il principio del doppio conteggio. concludiamo questo paragrafo con un ulteriore principio noto con il nome di principio del doppio conteggio. dati due insiemi finiti a e b, vogliamo contare gli elementi di una parte r dell’insieme delle coppie ordinate che come è usuale si denota con a x b. possiamo contare per questo il numero n delle coppie di r nei seguenti due modi diversi: si fissi l’elemento x nell’insieme a. denotiamo con n (x, —) il numero delle coppie di r, aventi x al primo posto. allora n = ∑ n (x, —) somma estesa al variare di x in a. nell’insieme si fissi y ε b. denotiamo con n (—, y) il numero delle coppie di r, aventi y al secondo posto. allora n = ∑ n (—, y) somma estesa al variare di y in b. vediamo alcuni esempi applicativi. problema - calcolare il numero dei lati di un cubo tridimensionale. vedasi ad esempio mauro cerasoli, franco eugeni, marco protasi, elementi di matematica discreta. bologna, zanichelli, . ibidem. is the golden section a key for understanding beauty? part iii sia f l’insieme delle facce ed s l’insieme degli spigoli di cui si vuole trovare il numero s. sia r l’insieme delle coppie faccia-spigolo appartenentisi in numero di n. risulta: n (x, —) = (ogni volta che x è fissato in f) n = ∑ n (x, —) = ( somma estesa al variare di x in a) n (—, y) = (ogni volta che y è fissato in s) n = ∑ n (—, y) = s (somma estesa al variare di y in b). dall’eguaglianza = n = s segue s = . naturalmente questo numero si poteva stabilire anche, e facilmente, contando gli spigoli su un modello, anche mentale, di cubo, ma la cosa non è così banale nel caso che segue: problema - calcolare il numero dei vertici e degli spigoli di un dodecaedro regolare. il dodecaedro ha facce pentagonali. sia f l’insieme delle f = facce pentagonali del dodecaedro e sia s l’insieme degli spigoli di cui si vuole trovare il numero s. sia r l’insieme delle coppie faccia-spigolo appartenentisi in numero di n. risulta: n (x,—)= (ogni volta che x è fissato in f), n(-,y)= (ogni volta che y è fissato in s) dunque: n = ∑ n (x, —) = x = ∑ n (—, y) = x s da cui s = . sia ora v l'insieme dei vertici in numero di v. contiamo le coppie vertice- spigolo appartenentisi. per ogni vertice passano tre spigoli. per ognuna delle facce ci sono spigoli. allora: n (x,—)= (ogni volta che x è fissato in v), n(-,y)= (ogni volta che y è fissato in s) n = ∑ n (x, —) = vx = n = ∑ n (—, y) = x da cui v = . problema - su un pallone da football ci sono disegnati un insieme p pentagoni ed un insieme e di esagoni. ogni pentagono ha un lato comune con un esagono. ogni esagono ha tre pentagoni e tre esagoni adiacenti. sapendo che sul pallone ci sono pentagoni, vogliamo sapere il numero degli e esagoni. franco eugeni and luca nicotra si ha per le coppie penta-esagoni adiacenti n (x,-) = e n (-, y)= , da cui x = xe, da cui e = . il paradosso del compleanno afferma che la probabilità che due persone in un gruppo compiano gli anni lo stesso giorno è largamente superiore a quanto potrebbe dire l'intuito! in tale caso il termine paradosso non è da intendersi nel senso di una contraddizione logica (antinomia), ma nel senso che la verità matematica contraddice l'intuizione naturale. fu il matematico austriaco richard von mises ( - ) che nel , quando era ad harvard, propose il problema nella interessante forma: quante persone ci devono essere in una stanza perché la probabilità che due di loro siano nate lo stesso giorno sia maggiore del % ? si è calcolato che la probabilità p(n) che due persone in un gruppo di n perone abbiano lo stesso compleanno è: p(n) = !/ n( -n)! p( ) = circa %; p( ) = circa %; p( ) = circa %; p( ) = % . la sezione aurea non basta più! tra bellezza e stupore: matematica e formule diceva il grande matematico britannico godfrey harold hardy ( – ), che ha presentato al mondo il genio indiano srinivasa ramanujan ( - ): le forme create dal matematico, come quelle create dal pittore o dal poeta, devono essere "belle"; le idee, come i colori o le parole, figura – dodecaedro regolare. is the golden section a key for understanding beauty? part iii devono legarsi armoniosamente. la bellezza è il requisito fondamentale: al mondo non c'è un posto perenne per la matematica brutta. si parla di “belle formule” in matematica. regina delle formule è considerata l’identità di eulero: ( ) eiπ = - che collega, misteriosamente, ma non tanto, i due numeri trascendenti e naturali allo stesso tempo: e , π con le due importanti unità, il numero e l’unità immaginaria i. la formula è una meraviglia, ma comprensibile ai soli esperti. È interessante introdurre le seguenti considerazioni sui numeri e , π e chiedersi: perché taluni li chiamano “naturali”, assimilandoli quasi agli oggetti del contare? molti rispondono a tale domanda affermando che essi si trovano in natura, proprio come la sezione aurea. per il numero e vi proponiamo un esperimento: prendete due chiodi, con un martello inchiodateli al muro, a una ugual distanza dal suolo e con una fissata distanza tra loro, per esempio cm. prendete ora una catena di lunghezza superiore ai cm. ad esempio cm, e appendetene gli estremi ai due chiodi predisposti al muro. si disegna una curva che sembra avere l’apparenza di una parabola, ma che una parabola non è! si tratta di una curva speciale denominata catenaria, che è data dalla formula : ( ) 𝑦 = 𝑒 𝑥+ 𝑒 −𝑥 = cosh x che è anche l’ovvio luogo dei punti medi (figura ) delle due funzioni esponenziali: ( ) y = e-x y = ex godfrey harold hardy, apologia di un matematico. trad. luisa saraval, milano, garzanti, . figura - la catenaria luogo dei punti medi. franco eugeni and luca nicotra la catenaria in letteratura è nota come coseno iperbolico dell’arco di x radianti. È interessante notare che così come il punto (cos x, sen x) descrive la circonferenza di equazione x + y = , in modo del tutto analogo il punto (cosh x, senh x), descrive l’iperbole equilatera di equazione x - y = , fenomeno incredibilmente bello per questa regolarità asimmetrica! più semplice forse comprendere perché sia considerato naturale il numero π, forse per il fatto che esprime il rapporto costante tra una qualsiasi circonferenza e il suo diametro! infatti prendiamo in esame un poligono regolare di n lati iscritto in una circonferenza di raggio r. il lato ab di tale poligono è la base di un triangolo isoscele che è simile all’analogo triangolo di una differente circonferenza di raggio r’ avente per lato il segmento a’b’. risulta chiaramente ( ) ab : r = a’b’: r’ ovvero: ( ) n ab : r = n a’b’ : r’ che esprime il fatto che il rapporto tra la lunghezza di un qualsiasi poligono regolare iscritto in una qualsiasi circonferenza al diametro della stessa è costante. come caso limite (o ragionando su opportune classi contigue di poligoni iscritti e circoscritti) implica la costanza (o meglio l’indipendenza dal raggio) del rapporto d’una circonferenza al suo diametro. un cenno a un singolare autore del ventennio fascista, dino segre ( - ), in arte pitigrilli è opportuna. una interessante formula matematica ragionando a posteriori e supposto di aver già definito π, osserviamo che il lato del poligono regolare di n lati iscritto in una circonferenza di raggio r vale ab = rcos(π/n). ne segue che la costante del rapporto tra poligono di n lati al diametro della circonferenza che lo circoscrive vale nab/ r = ncos (π/n). dino segre è stato un interessante personaggio del periodo del ventennio fascista. fu direttore e fondatore, dal , della rivista satirica «le grandi firme», spesso finito in tribunale per oscenità, ma fortemente protetto dall’ovra come ricordato in domenico zugaro, lettere di una spia, milano, sugar ed., . nel la rivista fu soppressa per motivi razziali. fu difeso e assolto nel da edvige mussolini, sorella del duce, per una accusa di antifascismo e tra il e il riparò in svizzera con la moglie lina furlan e il figlio pier maria furlan, futuro cattedratico in psichiatria a torino. siamo nel filone degli anni ’ , ove opere simili alimentarono l'interesse di un pubblico moderno e smaliziato alla ricerca di boutades e giochi di parole evoluti e destinati ad avere successo nel tempo ma anche di colta spregiudicatezza. opere del genere, considerate pornografiche, furono scritte, ad esempio, dall’antifascista mario mariani ( - ) e dall’israelita guido da verona ( - ), iniziatore del romanzo d’appendice in italia e is the golden section a key for understanding beauty? part iii molto bella è quella che porta il suo nome, formula che codificherebbe un rapporto numerico ideale tra le età di un uomo e di una donna prossimi a nozze. se indichiamo rispettivamente con d e u queste età, la formula è: d = u/ + , che conduce alla tabella , piuttosto maschilista. peccato che tale formula, pur essendo molto gradita al pubblico maschile, non ha alcun valore scientifico ed è del tutto inventata, quale perfetto atto di umorismo. tabella età uomo u età donna d in un lavoro di franco eugeni, dove è riportata la formula di pitigrilli, si asserisce che: «chiunque si sia interessato di divulgazione matematica co- nosce il magico potere che hanno le formule sul pubblico non specialistico». naturalmente queste formule devono avere alcune caratteristiche: • devono essere corte; definito il «d’annunzio delle sartine e delle manicure». da notare che tali opere venivano lette nascostamente dagli adolescenti, dalle signore e dai signori del tempo ed erano ad alta tiratura. umberto eco nel suo diario minimo gli dedica un interessante capitolo dal titolo “pitigrilli l’uomo che fece arrossire la mamma” per via dei suoi due romanzi cocaina ( ) e dolicocefala bionda ( ), caratterizzati da un umorismo a sfondo erotico, per questo considerati scandalosi al tempo, ma che oggi farebbero appena sorridere un’educanda. tra le numerosissime opere di pitigrilli ricordiamo in particolare mammiferi di lusso ( ), la cintura di castità ( ), oltraggio al pudore ( ) la vergine a diciotto carati ( ), e dopo tanti altri volumi, oltre cinquanta, delle sue short stories, raccolte di racconti graffianti, di costume, critici della società, umoristici che riletti oggi sono uno specchio significativo di una società borghese ricca, ipocrita, egoista descritta da uno scrittore brillante, egocentrico e deluso pubblicati, dal a dopo la guerra e ristampati in molteplici edizioni. narra dino segre (pitigrilli) in sette delitti ( ), uno dei suoi ultimi volumi, nel quale appare la citata formula (nel racconto il medium), che quando in qualche sua conferenza presentava la formula, vedeva molti signori sorridenti e incuriositi, estrarre di tasca una penna e annotare, quasi furtivamente la formula in un qualche foglietto apparso dal nulla. franco eugeni, le due rivoluzioni matematiche del secolo: da bourbaki alla matematica del discreto, op. cit., p. . https://it.wikipedia.org/wiki/erotismo franco eugeni and luca nicotra • i simboli che intervengono in esse devono essere di ovvia traduzione (codice universale); • devono presentare un giusto equilibrio tra la simmetria perfetta (di per se noiosa) e la completa casualità (non attraente e addirittura fastidiosa all’occhio). in altre parole una bella formula fa sempre il suo effetto. naturalmente “bella esteticamente” parlando, quasi come osservare un disegno di escher. osserviamo che in un disegno quasi tutto si vede con l’occhio, mentre in una formula parte si vede con l'occhio e parte con la mente. interessante circa le belle formule quella che interviene nel cosiddetto gioco di wythoff ( ), che costituisce un esempio di gioco, strettamente matematico, basato sulla sezione aurea. due mucchi di fiammiferi, due giocatori a e b i quali, a turno, devono prendere i fiammiferi dai mucchi secondo le seguenti regole: • il giocatore prende fiammiferi, in quantità totalmente arbitraria, da un solo mucchio; • il giocatore prende fiammiferi, in quantità sempre arbitraria, ma in numero uguale, da entrambi i mucchi; domanda: esiste una strategia vincente per a? affinché il giocatore a, che inizia il gioco, vinca è sufficiente che lasci le seguenti quantità: ( , ), nel primo mucchio ( , ), ( , ), ( , ), ......... nel secondo mucchio cioè, in generale la relazione fondamentale: ( ) ([nΦ] , [nΦ] + n) dove n è un numero qualunque e [nΦ] è la parte intera del numero nelle parentesi quadre. quindi da una qualunque mossa dell’avversario, a si può ricondurre a una quantità dettata sempre dalla stessa legge con n più piccolo. esplicitando willem abraham withoff ( - ) fu un matematico olandese cultore della combinatoria, delle tassellazioni e dei giochi. willem abraham withoff, a modification of the game of nim, nieuw archief voor wiskunde, ( - ), pp. – . vedasi anche: franco eugeni, ezio sciarra, raffaele mascella, matematica ed arte: il senso del bello, ….., op.cit. is the golden section a key for understanding beauty? part iii adesso la relazione fondamentale si ottengono i casi particolari precedentemente esposti: ( )’ e così via. la sezione aurea non basta più! tra bellezza e verità: fisica e formule il gusto estetico ha influenzato la ricerca scientifica e, in qualche caso, l’ha soccorsa nel suo cammino. nella scienza, la simmetria è associata spesso all’idea di bellezza. nella fisica, in particolare, la ricerca della simmetria nei fenomeni naturali ha sortito risultati notevoli. un primo esempio clamoroso è fornito dalle ricerche sui fenomeni magnetici ed elettrici compiute nel secolo xix dal grande fisico sperimentale michael faraday ( - ) e dal grande matematico e fisico teorico james clerk maxwell ( - ). faraday nel scopri sperimentalmente che un campo magnetico variabile genera un campo elettrico. nel maxwell riprese e formalizzò matematicamente in maniera simmetrica l’idea di faraday: un campo elettrico variabile genera un campo magnetico. una perfetta simmetria di “riflessione” delle leggi fisiche che, prima di scoprire tale simmetria, sembravano riguardare due campi distinti di fenomeni fisici: il magnetismo e l’elettricità. proprio grazie a questa simmetria, invece, maxwell potette legare fra loro nelle sue celebri equazioni, in una interazione reciproca, il campo elettrico e il campo magnetico, unificati in un unico “campo elettromagnetico”. ma cosa intendeva maxwell per interazione fra campo elettrico e campo magnetico? un campo elettrico variabile genera un campo magnetico che però, non esistendo nell’istante prima che fosse generato, è variabile e quindi genera un campo franco eugeni - raffaele mascella - daniela tondini, un’applicazione del calcolo binario: il gioco del nim, www.apav.it/master/gioconim.pdf. n =    ( ) ( ) , , , , =+ n =    ( ) ( ) , , , , =+ n =    ( ) ( ) , , , , =+ n=    ( ) ( ) , , , , =+ n =    ( ) ( ) , , , , =+ n =    ( ) ( ) , , , , =+ franco eugeni and luca nicotra elettrico. ma il campo elettrico così generato si va ad aggiungere a quello preesistente e, provenendo anch’esso da una situazione in cui non esisteva, è anch’esso variabile e quindi genera un altro campo magnetico variabile che genera un altro campo magnetico variabile e così via. siamo in presenza di una specie di “reazione a catena”, o meglio di un fenomeno autosostenentesi: un campo elettrico variabile genera un campo magnetico variabile che a sua volta genera un campo elettrico variabile, ecc. questa combinazione di campi elettrici e magnetici variabili, in grado di autosostenersi, costituisce un’onda elettromagnetica perché le perturbazioni dei due campi elettrico e magnetico si propagano nello spazio come un’onda. ancora l’irrinunciabile senso estetico della simmetria è alla base della teoria della relatività di albert einstein ( - ). le vere ragioni della genesi della teoria della relatività sono da ricercare nel subconscio di einstein e sono state chiaramente espresse da lui stesso: ragioni estetiche, oltre che filosofiche. sul ruolo dell’ideale di bellezza nell’opera scientifica di einstein, così si esprime banesh hoffmann: l’essenza della profondità di einstein stava nella sua semplicità; e l’essenza della sua scienza stava nel suo senso artistico, nel suo fenomenale senso della bellezza. ma cosa, nella fisica di fine ottocento, urtava il senso estetico del sedicenne albert? riferendosi al principio di relatività già affermato da galileo galilei, ad einstein sembrava «poco verosimile che un principio così generale, che vale con tanta precisione in un campo di fenomeni, riesca invece fallace in un altro campo». einstein osservava che il principio di relatività galileiana aveva già una grande generalità, essendo applicabile con successo nel vasto campo dei fenomeni meccanici, terrestri e celesti. pertanto riteneva inaccettabile che la natura non lo applicasse a tutti i fenomeni, compresi quelli ottici ed elettrodinamici. era dunque questa asimmetria nel campo della sua applicabilità che turbava il suo “senso estetico”. vale la pena soffermarsi su questa genesi della teoria della relatività di einstein, perché coinvolge in un unicum indivisibile: subconscio, luca nicotra, il disordine nell’ordine della materia, in «artescienza», anno iv, n. , p. . luca nicotra, l’ideale estetico nell’opera dello scienziato, in luca nicotra, rosalma salina borello (a cura di) nello specchio del’altro. riflessi della bellezza tra arte e scienza, roma, universitalia, , pp. - . banesh hoffmann, albert einstein: creatore e ribelle, (trad. it.), milano, bompiani, , p. . riportata anche in alice calaprice (a cura di), albert einstein. pensieri di un uomo curioso, milano, mondadori, , p. . francesco albergamo, storia della filosofia, palermo, palumbo, , p. . is the golden section a key for understanding beauty? part iii immaginazione e ricerca del bello nel senso più classico di ricerca della regolarità. il principio di relatività galileiana (o classica) asseriva che all’interno di un sistema di corpi isolato (cioè non soggetto a forze o soggetto a forze con risultante nulla) non è possibile eseguire alcun esperimento in grado di far capire se il sistema stesso si muove di moto rettilineo uniforme o è in quiete. il principio afferma l’invarianza delle leggi della meccanica rispetto a qualunque sistema di riferimento in quiete o in moto rettilineo uniforme. questo principio,valido nella meccanica, non sembrava valido per i fenomeni ottici ed elettromagnetici. einstein, a sedici anni, con uno di quegli esperimenti ideali (gedankenexperiment) realizzati con la fantasia - da lui coniati e ai quali ricorrerà spesso anche da scienziato - immaginava di cavalcare un’onda luminosa. ma perché ricorrere a un esperimento ideale, e quale può essere la sua validità? la risposta l’ha data magistralmente il grande fisico teorico max planck ( - ): un esperimento concettuale non è legato ad alcun limite di precisione, perché i concetti sono più sottili degli atomi e degli elettroni, ed in essi cessa anche il pericolo di un influsso causale dello strumento di misura sull’evento da misurare. il giovane albert immaginava di trovarsi a cavallo di un’onda luminosa e quindi di muoversi con la stessa velocità della luce. si chiedeva come avrebbe visto il mondo.una persona in una tale situazione non avvertirebbe più il fenomeno ondulatorio, perché non sarebbe attraversata dall’onda, muovendosi lei stessa rigidamente con questa: la luce scomparirebbe. e ciò accade soltanto quando il corpo si muove con la velocità della luce. dunque l’esperimento ideale del giovane einstein mostrava che, in contrasto con il principio di relatività galileiano, era possibile stabilire all’interno del sistema stesso, nell’ambito dei fenomeni ottico-elettromagnetici, se un corpo si muove o sta fermo, mostrando nel caso citato che si muove con la velocità della luce. una tale esperienza, teoricamente possibile, dimostrerebbe che il principio di relatività classico non sarebbe applicabile ai fenomeni ottico-elettromagnetici. a questa stessa conclusione, qui qualitativamente basata sull’esito dell’esperimento ideale del giovane einstein, si giunge formalmente verificando il cambiamento delle equazioni di maxwell nel passaggio da un sistema di riferimento in “quiete” ad uno in moto rettilineo uniforme: fino all’avvento della teoria della relatività di einstein si postulava l’esistenza di uno spazio assoluto e quindi di una quiete assoluta. max planck, scienza, filosofia e religione. milano, , fratelli fabbri editori, p. . ovviamente maxwell fa riferimento ad una quiete assoluta, oggi invece dimostrata inesistente. franco eugeni and luca nicotra ovvero le equazioni di maxwell valgono soltanto rispetto a un sistema di riferimento in quiete. questa conclusione non soddisfaceva il giovane albert, per il quale invece doveva valere in ogni caso il principio di relatività galileiano, affermando: esempi analoghi, come pure i falliti tentativi di constatare un moto della terra relativamente al mezzo luminoso [allude probabilmente all’etere dell’esperimento di michelson. nota d. a.] conducono alla presunzione che al concetto della quiete assoluta, non solo nella meccanica, ma anche nell’elettrodinamica, non corrisponda alcuna delle proprietà di ciò che si manifesta, ma che piuttosto, per tutti i sistemi di coordinate per i quali valgono le equazioni della meccanica, debbano anche valere le stesse leggi elettrodinamiche ed ottiche.[…] noi vogliamo elevare questa presunzione (il contenuto della quale verrà detto principio della relatività) a presupposto fondamentale e inoltre introdurre il presupposto, solo apparentemente incompatibile col precedente, che la luce nello spazio vuoto si propaghi sempre con una velocità determinata c indipendente dalla velocità del corpo emittente. i due esempi citati mostrano che la bellezza nella scienza, identificata nella simmetria è legata alla ricerca della verità in fisica. essa diventa il leit motiv dell’opera scientifica di uno dei fisici più geniali del novecento, ma taciturno e introverso fino a sfiorare l’autismo: paul adrien maurice dirac ( - ), scopritore dell’antimateria, di cui predisse l’esistenza nel in base a una sua famosa equazione: ( ) (iγµ ∂µ − m) ψ = un’altra notazione più compatta molto diffusa utilizza la notazione “a barra” introdotta da feynman /∂ ≡ γµ∂µ; per cui l’equazione di dirac si scrive come ( /∂ - m)ψ = ovvero /∂ ψ = m ψ, come è incisa sulla lapide dedicata a dirac nell’abbazia di westminster a londra (figura ). per dirac valeva il motto rinascimentale «pulchritudo splendor veritatis». per lo scopritore dell’antimateria laddove c’è bellezza c’è verità. il principio euristico della ricerca scientifica di dirac era dunque la bellezza: ricercare la verità in fisica per lui equivaleva a inseguire la bellezza. ma qual era l’ideale estetico di questo geniale fisico inglese di origine francese? era l’eleganza di un’equazione. quando gli chiesero cosa intendesse per eleganza di albert einstein, sull’elettrodinamica dei corpi in moto, in «annalen der physik», , , pp. - . trad. it. di paolo straneo in cinquant’anni di relatività, firenze, marzocco, , pp. - . luca nicotra, l’ideale estetico nell’opera dello scienziato, op. cit., pp. - ; per il significato e la comprensione dell’equazione di dirac si rimanda ai testi di fisica teorica. is the golden section a key for understanding beauty? part iii un’equazione, rispose: «non posso spiegarlo a chi non conosce la matematica, perché non comprenderebbe; mentre chi conosce la matematica sa già cosa intendo dire». la bellezza per dirac era qualcosa che non si poteva “spiegare” ma “sentire”, come accadeva a dante che non sapeva comunicare l’emozione che provava alla vista della sua beatrice e nel sonetto tanto gentile e tanto onesta pare (vita nuova) scriveva: mostrasi sì piacente a chi la mira, che dà per li occhi una dolcezza al core, che ‘ntender no la può chi no la prova: versi che esprimono in maniera sublime lo stesso pensiero di dirac. per fortuna, in altre occasioni, questo originalissimo fisico ha espresso più analiticamente il suo pensiero riguardo alla bellezza in matematica e quindi in fisica: per lui se un’equazione è elegante, prima o poi la teoria fisica sulla quale poggia si rivelerà vera, anche se quell’equazione temporaneamente non riesce a descrivere in maniera soddisfacente la realtà. e questo è proprio quello che è accaduto alla sua famosa equazione che nel prediceva teoricamente l’esistenza delle antiparticelle molti anni prima della loro scoperta sperimentale: la prima particella di antimateria, il positrone (l’antiparticella dell’elettrone) sarà sperimentalmente rivelata soltanto cinque anni dopo, nel , da carl david anderson. thomas kuhn, interview with dirac, - - , niels bohr archive, copenhagen, p. . trad. it. in etienne klein, sette volte la rivoluzione, milano, raffaello cortina, , p. . figura – la formula di dirac incisa sulla lapide commemorativa di paul dirac, inaugurata il novembre in una navata dell’abbazia di westminster (londra), vicina al monumento dedicato a newton. franco eugeni and luca nicotra quanto fosse stretto, per dirac, il rapporto tra bellezza, matematica e fisica risulta chiaramente espresso da lui stesso nel , quando, durante una visita all'università di mosca, accondiscendendo alla richiesta di scrivere alla lavagna una frase rappresentativa del suo lavoro, dirac scrisse: «una legge fisica deve possedere bellezza matematica». spesso si identifica la bellezza matematica con la semplicità; non era così per dirac che dichiarò a tal proposito: la teoria di newton è molto più semplice della teoria di gravitazione di einstein; ma la teoria di einstein è migliore, più profonda e più generale. la bellezza matematica, non la semplicità, è la caratteristica principale della teoria della relatività, e questo è il concetto fondamentale nella relazione esistente tra la fisica e la matematica. ma cosa intendeva dirac per “bellezza matematica”? i formalismi matematici, per lui, sono tanto più eleganti quanto più “invarianti” offrono, intendendosi per “invarianti” tutte quelle entità o quantità che non cambiano quando si effettuano trasformazioni geometriche (per es. una rotazione) o quando si cambia sistema di riferimento. e quanti più invarianti ci sono in una equazione, tanto maggiori sono la sua bellezza e quella della teoria fisica su di essa basata e la possibilità della sua esattezza. ma perché la bellezza, e quindi l’invarianza, risulta essere garante della verità di una teoria fisica? la risposta è concettualmente semplice: l’invarianza rispetto a una trasformazione (geometrica o di sistema di riferimento) è la prova più convincente dell’esistenza di un oggetto. in un primo momento, per esempio, io posso credere che l’oggetto che vedo da una certa angolazione sia un cubo, ma poi ruotandolo, mi accorgo che non lo è. se invece, pur cambiando diversi punti di vista, permane in me la vista prospettica di un cubo, mi convincerò che effettivamente quell’oggetto è un cubo. questo in estrema sintesi il pensiero di dirac: la bellezza di una equazione matematica porta all’invarianza e questa alla verità: la bellezza matematica conduce dunque alla verità fisica. la sezione aurea non basta più! tra bellezza e stupore : immagini e computer graphics andando avanti nei nostri esempi osserviamo che anche l’informatica ha provveduto abbondantemente a presentarci casi interessanti di “bellezza” non juan antonio caballero carretero, dirac, l' antimateria: il lato oscuro della materia, rba, . is the golden section a key for understanding beauty? part iii convenzionale, specialmente quando sono stati illustrati attraverso la computer graphics. l’utilizzo del computer ha in realtà creato campi del tutto nuovi nella matematica applicata, come ad esempio la teoria del caos e la geometria frattale, nei quali si sono avuti sviluppi addirittura impensabili senza l’ausilio della computer grafica. benoit mandelbrot ( - ), padre della geometria frattale, riconosce ai computer il ruolo di strumenti insostituibili per questo campo di ricerca. prendiamo in esame una semplice formula di ricorrenza: ( ) zn+ = zn + c dove zn= xn+i yn , c= a+i b sono numeri complessi. supposto z = , la successione: ( ) z , z , z , … , zn, … a seconda del valore di c, può o no essere limitata. essendo c= (a,b) assimilabile alle coordinate cartesiane di un punto, si chiama frattale di mandelbrot, il luogo dei punti c del piano di argand-gauss per i quali la successione sopra indicata è limitata. senza l’avvento della computer grafica sarebbe stato impossibile visualizzare questo luogo (figura ) l’equazione ricorrente può scriversi nella forma cartesiana: xn+ = xn - yn + a , yn+ = xnyn + b benoit mandelbrot, les objects fractals: forme, hazard et dimension, paris, flammarion, ; benoit mandelbrot, fractals and chaos: the mandelbrot set and beyond, springer, ; benoit mandelbrot, la formula della bellezza. la mia vita di vagabondo della scienza. milano, rizzoli, . fig. – frattale di benoit mandelbrot. fig. – colori esterni. https://it.wikipedia.org/w/index.php?title=gli_oggetti_frattali._forma,_caso_e_dimensione&action=edit&redlink= https://it.wikipedia.org/wiki/ https://it.wikipedia.org/wiki/rizzoli franco eugeni and luca nicotra le equazioni cartesiane di mandelbrot si prestano ad immediate generalizzazioni sia a forme quadratiche più generali, o anche cubiche e di gradi più alti, e anche non necessariamente algebriche. nella “giungla di immagini” che ne derivano non è difficile reperirne altre di incredibile bellezza. tornando al frattale di mandelbrot, osserviamo solo che le proprietà di questa figura sono a dir poco incredibili. si tratta di un oggetto geometrico dotato di omotetia interna, in quanto si ripete nella sua forma originale e allo stesso modo, su scale diverse anche sempre più piccole. dunque ingrandendo una qualunque sua parte si ottiene una figura simile all'originale (autosomiglianza). se pensiamo al contorno del frattale come a una curva, questa curva in ogni suo punto è priva di retta tangente! una sostanziale differenza fra la rappresentazione di una curva piana e di un frattale è, nei fatti, il modo in cui l’oggetto si costruisce. una curva piana si costruisce generalmente sul piano cartesiano, utilizzando le equazioni parametriche x = x(t), y = y(t): al variare del parametro t varia la posizione del punto della curva sul piano, che in tal modo la descrive. la costruzione dei frattali, invece, non si basa su equazioni, ma su un algoritmo che seleziona punti di “differente natura” o, se si vuole, di “differente colore”. in prima approssimazione si dividono i punti in due classi: quelli per i quali la successione diverge e quelli per i quali la successione converge, assegnando ai punti due colori diversi. ma in una fase successiva possiamo graduare le convergenze, indicando convergenze inferiori a numeri dati e ottenere ulteriori partizioni e colori. si può provare che se |z | > , allora la successione diverge e quindi il punto c = (a,b) è esterno al frattale di mandelbrot. le immagini multicolori che si vedono nella figura , sono generate colorando i punti esterni all'insieme in dipendenza di "quanto rapidamente " la successione diverge all’infinito. il minimo valore di n per cui |z | > è un indice di quanto "lontano dal contorno" si trova un punto e viene utilizzato per la rappresentazione "a colori". ancora possiamo trovare il minimo n per il quale ad esempio |z | > e così via… paradossalmente, i punti colorati che conferiscono il fascino al frattale di mandelbrot sono proprio quelli che non appartengono all'insieme. is the golden section a key for understanding beauty? part iii l'algoritmo non è mai applicato una volta sola: può essere iterato un numero di volte teoricamente infinito. a ogni iterazione, la curva si avvicina sempre più al risultato finale e, dopo un certo numero di iterazioni, l'occhio umano non è più in grado di distinguere le modifiche (inoltre l’hardware non è più in grado di consentire ulteriori miglioramenti). pertanto, quando si disegna concretamente un frattale, ci si può fermare dopo un congruo numero di iterazioni. il frattale di mandelbrot, al di la della comprensione scientifica del fenomeno, presenta tutte le caratteristiche del “bello”: se si espone come poster! È significativo e cattura l’attenzione di una qualunque persona così come una bella musica colpisce l’uditore anche sprovveduto. dunque sono immagini molto utili per la pubblicità, come appare nella maglietta di figura sulla quale è stampato un frattale di mandelbrot. si ritiene che in qualche modo i frattali abbiano delle corrispondenze con la struttura della mente umana, è per questo che la gente li trova così familiari. questa familiarità è ancora un mistero e più si approfondisce l'argomento più il mistero aumenta. figura – la curva di koch. fig. . logica iterativa ad albero del frattale. fig. . l’albero di pitagora. fig. . maglietta con il frattale di mandelbrot. franco eugeni and luca nicotra una piccola variazione nella formula di mandelbrot ( ) zn+ = (*zn) + c dove *(a+ib) = a-ib è il complesso coniugato del numero dato, conduce a una figura totalmente diversa ma egualmente molto bella. una curva interessante di tipo patologico, riportata in tutti i testi, è la curva del matematico svedese helge von koch ( - ) presentata nel come esempio di funzione continua e non derivabile in alcuno dei suoi punti, costruita con un processo iterativo (figura ). il concepire una curva priva di retta tangente in ogni suo punto è un antico problema considerato patologico nella matematica. una curva siffatta fu scoperta nel , prima di quella di von koch, da giuseppe peano ( - ), ma da un lato ebbe minore diffusione mentre da un altro lato si presentava patologicamente molto più interessante, per il fatto che si tratta di una sequenza di curve, la cui curva limite del processo, che non si vede, permette di intuire che in essa ogni punto è uno “spigolo” , quindi privo di tangente, e inoltre si intuisce anche che la curva limite riempie interamente il quadrato (figura )! naturalmente la curva limite può essere studiata, ma ciò esula dalla nostra trattazione. uno dei personaggi di grande interesse, che deve molto all’avvento dell’informatica, è il fisico, matematico e cosmologo inglese sir roger penrose (n. ) molto famoso per avere ideato alcune figure impossibili che portano il suo nome (figure e ). oltre ai grandi contributi forniti in vari campi helge von koch, sur une courbe continue sans tangente, obtenue par une construction géométrique élémentaire, archiv för matemat., astron. och fys. , , pp. - . eric w. weisstein, curva di peano, in mathworld, wolfram research. fig. - la curva di peano. https://it.wikipedia.org/wiki/mathworld is the golden section a key for understanding beauty? part iii - specialmente l’astrofisica, l’intelligenza artificiale e la filosofia della scienza - penrose ha lavorato anche nella cosiddetta “matematica creativa” e ha scoperto nel , assieme a robert amman ( - ), una particolare tassellatura che porta il suo nome (penrose tiling). si tratta di un pattern di figure geometriche basate sulla sezione aurea, in quanto costituite da triangoli aurei. esistono diverse tassellature del tipo penrose. una delle più utilizzate è composta da due tasselli, a forma di rombo, ognuno avente quattro lati di lunghezza unitaria (figura ), legate entrambe alla sezione aurea: un tassello ha due angoli di ° e due di °; l'altro tassello ha due angoli di ° e due di °. roger penrose, la mente nuova dell’imperatore, milano, rizzoli (bur), . figura – le tassellature di roger penrose. figura – il triangolo impossibile di roger penrose e il logo dell’app. google drive. figura – la losanga impossibile di roger penrose e il logo della renault. franco eugeni and luca nicotra la sezione aurea non basta più! tra bellezza e coazione: le immagini nella pubblicità spesso noi ci chiediamo: che cos’è la pubblicità? qual è il suo scopo? il concetto di pubblicità è, secondo il semiologo triestino ugo volli, uno «strumento estetico e ideologico di massa, serbatoio a cui attingiamo il nostro modo di guardare le cose, di scoprire il bello, di divertirci e sognare». naturalmente la pubblicità, o meglio il messaggio pubblicitario, è una forma di comunicazione che utilizza i più svariati linguaggi, quali il testo, le immagini, le parole, la musica, tutti trasformati in opportune sequenze binarie, per poter essere diffusi in rete da internet nei nuovi canali di vendita, quali amazon, o i cosiddetti social network, come instagram e altri simili, ancora si ricorre a tecnologie più semplici, ma ancora efficaci, che si servono del flyer (volantino), del cartellone, dell’inserzione sui giornali, dell’insegna, sempre al fine di permettere la conoscenza e il costo dei prodotti, gli eventi culturali e sociali, gli spettacoli, in generale ogni tipo di servizi adatti ugo volli, semiotica della pubblicità, bari-roma, laterza, . ugo volli è professore ordinario di filosofia e teoria dei linguaggi, presso l’università di torino). il “ linguaggio” finale che permette a un computer di eseguire un programma è costituito da una sequenza di cifre binarie e (programma oggetto). figura is the golden section a key for understanding beauty? part iii a un pubblico di massa (figure , ). spesso la pubblicità, specie quella meno corretta, si basa su tecniche di “lavaggio del cervello”. i servizi segreti furono i primi ad adottare queste tecniche di controllo della mente - scoperte durante le guerre - in seguito utilizzate e sfruttate anche dal settore pubblicitario, al quale, negli anni ’ del secolo scorso, la psicologia offrì un campo illimitato di potenziali manipolazioni. queste erano peraltro considerate fondamentali nell'ottica di una sempre crescente prosperità. infatti, secondo una regola fondamentale dell’economia, l'offerta è regolata dalla domanda. grazie alle manipolazioni psicologiche della mente, si può indurre negli uomini un bisogno incessante (spesso non reale) di consumi, incrementando così la domanda e quindi il processo produttivo per soddisfarla. ogni incremento del potere di acquisto del consumatore si trasforma così in nuova domanda che genera nuova offerta. a metà degli anni cinquanta del secolo scorso, soprattutto negli stati uniti, il conformismo rappresentava il fondamento della nuova e quanto mai prospera società. per fabbricanti e pubblicitari, il "colletto bianco" era la figura ideale, che andava allettata con tutte le tecniche della manipolazione psicologica. le industrie cominciarono a utilizzare tali tecniche non solo sui consumatori ma anche sui propri dipendenti. i test e i profili psicologici divennero una pratica comune per stabilire la "normalità" del personale verificandone il conformismo. l'insidiosità del processo in atto non sfuggì agli studiosi più attenti, quali vance packard ( - ) e john kenneth vance packard, i persuasori occulti, torino, einaudi, . figura . . franco eugeni and luca nicotra galbraith ( - ). scrive galbraith, con l'ironia e l'autorevolezza che lo hanno reso tra i pensatori più originali del novecento, che la «società opulenta» demolisce alcuni miti e svela l'inganno della «mentalità convenzionale» che impedisce di guardare al di là delle leggi di mercato. solo quando il benessere riguardava pochi eletti, aveva un senso porre l'accento sulla produzione. davanti a una società agiata, ma massificata, è del tutto errato fare della produttività il centro e il fine dell'economia, poiché in tale errore si può rinvenire l'origine di molte delle contraddizioni che caratterizzano il nostro tempo. pertanto, appare chiaramente che lo scopo del messaggio pubblicitario, che dovrebbe essere informativo-commerciale, sia in realtà un “oggetto” ben più complesso. ad esempio, nel presentare le qualità e i pregi di un prodotto, si opera in maniera manipolativa, così da fornire informazioni esclusivamente appaganti i potenziali clienti, così da spingere un’alta percentuale di essi all’acquisto. nel suo libro la galassia gutenberg, herbert marshall mcluhan sottolinea l'importanza dei mass media e illustra come l'avvento della stampa nel produsse il passaggio dalla cultura orale alla cultura testuale, ponendo al centro dell’attenzione un solo senso: la vista, che egli considera un tipo di relazione che distanzia i singoli e che è meno emotiva. così egli propone un necessario ritorno alla comunicazione orale, che si veicola attraverso l'udito e ci avvolge, poiché il suono si propaga in ogni direzione, è più coinvolgente e amplifica il nostro senso di comunità. comunicando quindi attraverso il senso della vista, tendiamo pertanto a esercitare maggiormente la nostra singolarità e razionalità. egli asserisce che «quale che sia il mezzo tecnologico utilizzato, questo produce effetti persuasivi sull'immaginario collettivo, in modo indipendente dal contenuto informativo presentato». volendo avanzare una critica a mcluhan circa l’identificazione del mezzo (medium) con il messaggio va notato che, secondo altri autori, non sarebbe affatto vero che il pubblico sia indifferente ai contenuti, come invece asserisce mcluhan parlando anche della sua idea di “villaggio globale”. si tratta di una intrigante metafora, atta a indicare come l'evoluzione dei mezzi di comunicazione e la costruzione di comunicazioni via satellite hanno john kenneth galbraith, la società opulenta, roma, edizioni di comunità, (rieditato ). herbert marshall mcluhan ( - ) è stato un sociologo, filosofo, critico letterario e professore canadese. herbert marshall mcluhan, the gutenberg galaxy: the making of typographic man (routledge & kegan paul). (ed italiana del ). herbert marshall mcluhan, understanding media: the extensions of man, gingko press, . herbert marshall mcluhan, quentin fiore, il medium è il messaggio, milano, feltrinelli, . is the golden section a key for understanding beauty? part iii permesso sia comunicazioni in tempo reale sia comunicazioni a grande distanza. in altre parole, la “geometria del web satellitare” sarebbe uno spazio- tempo nel quale la distanza di due punti distinti è zero e il tempo di percorrenza da un punto a un altro è il tempo delle e-mail, prossimo a zero. così ci piace asserire come il mondo, “diventato piccolo” ha assunto il comportamento usuale di un villaggio: oggi, dopo più di un secolo di tecnologia elettrica, abbiamo esteso il nostro sistema nervoso centrale fino a farlo diventare un abbraccio globale, abolendo limiti di spazio e tempo per quanto concerne il nostro pianeta. il concetto alla base di questa affermazione, come abbiano sostenuto in varie occasioni, è il fatto che la tecnologia elettronica è diventata una effettiva protesi dell’intera umanità. in ogni caso, seguendo mcluhan, può ipotizzarsi che il linguaggio pubblicitario attuale sia una sorta di meta-pubblicità, sempre la medesima, nella quale di volta in volta cambiano immagini e prodotto, ma non cambia la “storia presentata”. pertanto le pubblicità non opererebbero per vendere i singoli prodotti, ma affinchè in ogni caso qualche acquisto sia fatto, utilizzando quella modalità che il nostro famoso semiologo umberto eco ( - ) definisce «coazione al consumo», operazione che spinge i potenziali clienti fuori di casa a comprare qualcosa, magari anche molto diversa da quella che avevano in mente e che non desideravano affatto voler acquistare. il semiologo francese roland barthes ( - ), nelle sue molteplici opere, si è dedicato allo studio delle relazioni esistenti tra i miti-feticci della realtà contemporanea e il sociale, con particolare riguardo al mondo della moda. ha studiato il rapporto di incontro-scontro tra la lingua intesa come patrimonio collettivo e il linguaggio individuale. il criterio da lui proposto oltrepassa la tesi accademico-filologica e si pone come una continua e sollecita interrogazione del testo, facendo notare che il pubblico di oggi cerca di appropriarsi, con personali interpretazioni ed elementare ermeneuticità, del messaggio pubblicitario, tentando sia di falsificarlo, sia di attribuire ad esso una nuova forma, magari oggetto del desiderio individuale. tuttavia, per uscire dal banale, occorre osservare che comunque il messaggio deve rimanere impresso attraverso slogan facilmente leggibili, utilizzando immagini che herbert marshall mcluhan, bruce-r-powers the global village, oxford university press, . umberto eco (a cura di), estetica e teoria dell'informazione, milano, bompiani, . roland.barthes, miti d'oggi, (trad. lidia lonzi), torino, einaudi, (nuova ed. ). roland barthes, sistema della moda, trad. lidia lonzi, torino, einaudi, (nuova ed. ). franco eugeni and luca nicotra colpiscano l’inconscio, o un manifesto o un banner, che comunque viene visualizzato soltanto per qualche frazione di secondo. inoltre, le parole del messaggio pubblicitario devono essere poche e facili da ricordare, devono avere la medesima efficacia di un collaudato marchio di una casa di produzione, devono ispirare, a colpo d’occhio, serietà, fiducia, la convinzione di un ottimo acquisto. il messaggio commerciale deve necessariamente contare sull’impatto combinato di una immagine con uno slogan e su una collocazione opportuna. ad esempio un manifesto deve necessariamente collocarsi in posti strategici, ad elevato traffico di circolazione di persone (piazze, stazioni ferroviarie, autobus e pensiline di attesa di mezzi pubblici, strade centrali trafficate ecc.). la semiotica è la disciplina principe di questo mondo, avendo per obiettivo l’analisi profonda del testo. esamina ogni messaggio pubblicitario, le strutture di senso, la sintassi, i modelli semantici del testo, tentando di andare al di là delle purtroppo molto diffuse letture superficiali. oggi un pubblicitario, che voglia analizzare quali siano gli effetti delle comunicazioni di massa, deve essere consapevole che questa è portata a tal punto da livellare e conglobare in un modello standard le notizie, che per quantità e similitudine offrono al proprio pubblico una specie di rumore che non sappiamo se definire indifferenziato o addirittura bianco. la filosofia del linguaggio e della comunicazione, seguendo ancora umberto eco, asserisce che il pubblicitario, nell’innovarsi, dovrebbe porsi in una posizione intermedia fra gli apocalittici, che pensavano che le tecnologie delle comunicazioni avrebbero massificato l’intero universo umano, e gli integrati, i quali erano al contrario fiduciosi in una divulgazione globale dei valori culturali che li avrebbero resi alla portata di tutti. nella pubblicità vi sono alcune immagini, provenienti da intuizioni grafiche sorprendenti, come le immagini del cosiddetto “effetto droste” o delle ripetizioni infinite nate, con la pubblicità della olandesina del cacao droste e similari, dalla matematica o da ambienti creativi molto vicini a tale disciplina, delle quali abbiamo accennato nei paragrafi precedenti, quali le figure proposte dall’incisore escher, dall’astrofisico penrose, dai cosiddetti frattali, figure che pur comprensibili solo da esperti nei loro dettagli, costituiscono uno stimolo visivo notevole. umberto eco, apocalittici e integrati, milano, bompiani, e semiotica e filosofia del linguaggio, torino, einaudi, . is the golden section a key for understanding beauty? part iii seguendo l’ipotesi di mcluhan, in sintesi si può affermare che "il medium è il vero messaggio", indipendentemente se il prodotto commercializzato sia un buon prodotto, se un libro sia un buon libro o se il capo di abbigliamento sia un buon capo o ancora se il prezzo sia reale o legato invece all’importanza che all’oggetto viene attribuito dall’intera comunità dell’ignaro ricevente. oggi una operazione del genere è traslata anche dagli oggetti al cibo, l’immagine che una comunità attribuisce ad uno scelto chef di turno ha sostituito il giudizio individuale sul prodotto dello chef, così che la bontà del suo prodotto è solo funzione dell’immaginario collettivo. noi assistiamo a un fenomeno antico, che è giusto chiamare di “persuasione occulta” ovvero di “lavaggio del cervello”, del quale sarebbe interessante tracciare una mini-storia. questo è stato il mondo di ieri per certi aspetti, ma per altri questo è il nostro mondo di oggi! figura . franco eugeni and luca nicotra bibliografia albergamo f. 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( ). lettere di una spia, milano, sugar editore. buying beauty: buying beauty: on prices and returns in the art market luc renneboog and christophe spaenjers* this version: december abstract: this paper investigates the price determinants and investment performance of art. we apply a hedonic regression analysis to a new data set of over one million auction transactions of paintings and works on paper. based on the resulting price index, we conclude that art has appreciated in value by a moderate . % per year, in real u.s. dollar terms, between and . this is a performance similar to that of corporate bonds – at much higher risk. a repeat-sales regression on a subset of the data demonstrates the robustness of our index. next, quantile regressions document larger price appreciations in higher price brackets. we also find variation in historical returns across mediums and movements. finally, we show that both high-income consumer confidence and art market sentiment forecast art price trends. key words: art; auctions; hedonic regressions; investments; repeat-sales regressions; sentiment. * luc renneboog (luc.renneboog@uvt.nl) is professor of corporate finance, tilburg university, the netherlands. christophe spaenjers (spaenjers@hec.fr) is assistant professor of finance, hec paris, france. the authors would like to thank sofiane aboura, richard agnello, david bellingham, fabio braggion, michael brennan, peter carpreau, geraldo cerqueiro, gilles chemla, mark clatworthy, craig clunas, peter de goeij, neil de marchi, alberta di guili, elroy dimson, kevin evans, julian franks, rik frehen, edith ginglinger, victor ginsburgh, marc goergen, william goetzmann, tom gretton, duncan hislop, noah horowitz, jonathan ingersoll, martin kemp, marius kwint, geraldine johnson, benjamin mandel, david marginson, bill megginson, allison morehead, thierry morel, michael moses, kim oosterlinck, liang peng, rachel pownall, clara c. raposo, catarina reis, keith robson, frans de roon, geert rouwenhorst, ahti salo, sofia santos, marie shushka, mick silver, myron slovin, cindy soo, matthew spiegel, darius spieth, peter szilagyi, nick taylor, svetlana taylor, radomir todorov, hans van miegroet, joost vanden auwera, stephen walker, jason xiao, roberto zanola, and participants at seminars and workshops at antwerp university, cambridge university, cardiff business school, duke university, iscte business school, london business school, manchester business school, paris-dauphine university, tilburg university, ucl-core, universidade catolica portuguesa, universidade nova de lisboa, yale university, the fma meetings, the lbs annual art investment conference, and the multinational finance conference for valuable comments and suggestions. spaenjers would like to thank the netherlands organisation for scientific research (nwo) for financial support, and london business school for its hospitality. i. introduction stories about the baffling amounts of money paid for first-tier art frequently entertain newspaper readers around the world. yet, high prices do not necessarily imply high returns. consider, for example, claude monet’s “dans la prairie”, the star lot of the impressionist and modern art evening sale at christie’s london in february . the canvas changed owners for the substantial sum of million british pound (gbp), and was the top seller in an auction that, according to the wall street journal ( ), “showed that there's plenty of life” in the impressionist and modern sector. however, the same painting had been sold twice before in recent history – in june at sotheby’s london for . million gbp, and in november at sotheby’s new york for . million u.s. dollars (usd). by any standard, the rate of return on the monet was dismal. nevertheless, the growth in the number of multi-million dollar sales, the expansion of the global population of high-net-worth individuals, and the increasing need for portfolio diversification have all brought increased attention to art as an investment in recent years. in turn, the belief in art as a viable alternative asset class has led to the creation of several art funds – not all very successful (horowitz, ) – and art market advisory services which cater to affluent individuals who consider investing in art. the wall street journal ( ) recently reported that almost % of total wealth is held in so-called “passion investments”: art, musical instruments, wine, jewelry, antiques, etc. of all such luxury assets, art is the most likely to be acquired for its potential appreciation in value (capgemini, ). there is a growing academic literature on art investments, but previous studies have utilized relatively small data sets of sales (pairs) at the high end of the market. the resulting indices are prone to a number of estimation issues and selection biases (cf. section ii). the current paper therefore uses a comprehensive new data set of nearly . million auction sales to re-examine the price formation and returns in the art market, over a period from to . we perform a hedonic regression analysis which relates transaction prices to a wide range of value- determining characteristics and year effects. our results show that artist reputation, attribution, signs of authenticity, medium, size, topic, and the timing and location of the sale are significantly correlated with price levels. based on the regression coefficients on the year dummies in our model, we can build a price index that controls for time variation in the composition of the market (and corrects for changes in price dispersion). we find that constant-quality art prices increased by a moderate . % in real usd terms on a yearly basis over the - period. between and , the geometric average annual real return is . %. for the second half of the twentieth century, our estimates are substantially below those reported by goetzmann ( ) and mei and moses ( ). our baseline hedonic index proves robust to alternative specifications and estimation methods. for example, allowing for time variation in the hedonic coefficients does not materially affect our results. importantly, also applying a repeat-sales regression to a subset of our sample leads to nearly identical return estimates for the - period. quantile regressions over the same time frame show that historical rates of appreciation vary across the price distribution; the annualized real return at the th percentile is almost percentage points higher than the return at the th percentile. in line with this finding, but in contrast to previous research (and to what the monet example may suggest), we do not find that portfolios of masterpieces underperform the rest of the market. moreover, a “value” strategy, in which one focuses on important but relatively less expensive artists, has outperformed our baseline index by . percentage points on an annualized basis. next, we show that oil paintings and post-war movements have outperformed other art over the last few decades. overall, the risk-return profile of art has been inferior to that of financial assets, even before transaction costs, especially in the second half of our time frame. however, art has outperformed other physical assets, such as gold, commodities, and real estate. while we find a low correlation between changes in the art price index and same-year equity returns, the correlation with lagged equity returns is substantially higher. finally, we examine the determinants of art market returns. we find evidence that (lagged) equity market returns and changes in high-income consumer confidence predict art returns, highlighting the importance of luxury consumption demand. however, we document that also a novel art buyer sentiment measure (based on volume and buy-in rates at high-profile auctions, and on media reports) forecasts price changes. this suggests that time-varying optimism about the potential of ‘art as an investment’ can partially explain the existence of art market cycles. ii. literature on art returns researchers have used different methodologies to calculate the financial returns on art investments, starting from public auction records. stein ( ) considers the auctioned objects in each year as a random sample of the underlying stock of art (by deceased artists), and constructs an index based on the yearly average transaction price. baumol ( ) and frey and pommerehne ( ) calculate the geometric mean return on works that sold at least twice during the considered time frame. unfortunately, however, these simple methods do not enable the construction of a price index that adjusts for variations in quality. most recent studies have therefore used either repeat-sales regressions or hedonic regressions to measure the price movements of art and other infrequently traded assets (e.g., real estate). repeat-sales regressions (rsr) explicitly control for differences in quality between works by only considering items that have been sold at least twice. the method uses purchase and sale price pairs to art is not only sold at auction, but also privately, for example through dealers. total turnover in the art and antiques market is roughly split equally between the two transaction types (mcandrew, ). however, it is generally accepted that auction prices set a benchmark also used in the private market. estimate the average return of a portfolio of assets in each time period. pesando ( ), goetzmann ( ), mei and moses ( ), and pesando and shum ( ), among others, have applied the methodology to art investments. there are three problems with existing rsr studies. first, since art objects trade very infrequently (and resales can be hard to identify), only considering repeated transactions decimates any data set to a relatively small number of observations. for example, mei and moses ( ) include , sales pairs over a period of years; goetzmann et al. ( ) use even fewer sales pairs, although their focus is not on the resulting price index itself. meese and wallace ( ) show that the use of such small databases renders rsr estimators sensitive to influential observations. second, most repeat-sales studies suffer from selection issues. for example, the sample used by mei and moses ( ) includes sales pairs with a first transaction anywhere in the world, but a resale at sotheby’s or christie’s new york – arguably the most expensive sales rooms in the world. moreover, the initial purchase is identified using the provenance entries in the new york sales catalogues; this information could be more likely to be included when a high price is expected. an index estimated based upon such a sample may thus be biased upwards. other studies, including goetzmann ( ), have utilized repeat-sales information from the so-called “reitlinger data” – books with auction price data until the s – of which is well known that they are incomplete and focus disproportionately on famous artists (guerzoni, ). third, even abstracting from the issues just outlined, items which trade twice may in general not be representative for the overall population of art works. hedonic regressions control for quality changes in the transacted goods by attributing implicit prices to their “utility-bearing characteristics” (rosen, ). in the often-used time-dummy variant of the hedonic pricing methodology, all available transaction data are pooled, and prices are regressed on a set of value- determining attributes and one or more time dummies. under the assumption that all omitted characteristics are orthogonal to those included (meese and wallace, ), the coefficients on the time dummies account for constant-quality price trends over the sample period. since no information is thrown away prior to the estimation, hedonic regressions make efficient use of available data, and may therefore give more reliable estimates of price indices than rsr. not surprisingly, one of the key difficulties is the choice of hedonic characteristics (ashenfelter and graddy, ). observable and easily quantifiable features such as size, medium, and the location of sale are frequently used (anderson, ; buelens and ginsburgh, ; chanel et al., ; agnello and pierce, ), but the number of hedonic variables often remains relatively limited. the literature has failed to systematically include variables that measure reputation or the strength of attribution, an important price-determining factor for old masters (robertson, ). also, just like in studies using rsr, the utilized samples have been relatively small and selective. research has been based although there are omitted variables in every model, hedonic pricing is particularly suitable for luxury consumption goods markets, in which a limited number of key characteristics often determine the willingness to pay for an item (e.g., the cs of a diamond). in any case, butler ( ) argues that the omitted variable bias is often negligible; “approximate correctness can be achieved with significantly fewer characteristics than is generally supposed”. either on the problematic (and old) reitlinger data mentioned before (buelens and ginsburgh, ; chanel et al., ), or on samples of art from one country (agnello and pierce, ; renneboog and van houtte, ; higgs and worthington, ). the estimated returns on art vary with data, methodology, and the time period under consideration (ashenfelter and graddy, ). with respect to paintings, the two most influential repeat-sales studies report relatively high real returns over the second half of the twentieth century. goetzmann ( ) calculates an average annual real appreciation of . % between and , but with a “long and strong” bull market, in which annualized returns average around %, since . mei and moses ( ) reports a real return of . % over the period - , but a higher annualized return estimate of . % after . (for prints, pesando and shum ( ) report much lower returns over the period - .) in general, studies that use hedonic regressions have found somewhat lower returns, but to date no exhaustive hedonic analysis has been undertaken. iii. data and methodology in this paper, we construct a price index for art using the hedonic regression methodology. as outlined before, the main advantage of this approach is that information on all observed transactions can be taken into account. our model relates the natural logs of real usd prices to year dummies, while controlling for a wide range of hedonic characteristics: ∑ ∑ = = +++= m m t t ktkttmktmkt dxp ln εγβα ( ), where pkt represents the price of art object k at time t, xmkt is the value of characteristic m of item k at time t, and dkt is a time dummy variable that takes the value one if object k is sold in period t (and zero otherwise). the coefficients βm reflect the attribution of a relative shadow price to each of the m characteristics, while the antilogs of the coefficients γt can be used to construct an art price index that controls for time variation in the quality of art sold. the value of the hedonic index in year t is: *)exp( tt γ≡Π ( ), with γ set equal to for the initial, left-out period. the return in year t is then: − Π Π ≡ −t t tr ( ). however, a subtle (and often neglected) point is that such an index will track the geometric – not the arithmetic – mean of prices over time, due to the log transformation prior to the estimation. this is especially important for our estimation of returns if there is time variation in the heterogeneity-controlled dispersion in prices, i.e., the hedonic regression residuals (silver and heravi, ). if we assume that the residuals of our hedonic regression are normally distributed in each period, with variance tσ in period t, then we can correct for this transformation bias by defining the corrected index values as follows (triplett, ; silver and heravi, ): *)( exp *     −+≡Π σσγ ttt ( ). the corrected return in year t, can then be defined as follows: * * * − Π Π ≡ −t t tr ( ). we describe our data in subsection a. the hedonic variables that will be used in the estimation of eq. ( ) are presented in subsection b. a. data we focus on the market for oil paintings and works on paper (i.e., watercolors and drawings), which account for a substantial proportion of all transactions – and about % of total turnover – in the art market (artprice, ). we start by compiling a list of artists. this selection of artists has to be as exhaustive as possible, so as not to have a bias towards artists that are popular today, and therefore we consult several authoritative art history resources from different time periods. our artist selection procedure, of which details can be found in appendix a, culminates in a list of , artists. we classify , of those artists in at least one of the following art movements: medieval & renaissance; baroque; rococo; neoclassicism; romanticism; realism; impressionism & symbolism; fauvism & expressionism; cubism, futurism & constructivism; dada & surrealism; abstract expressionism; pop; minimalism & contemporary. we then collect data on all relevant sales by matching our list of names with all artists in the online database art sales index [http://www.artinfo.com/artsalesindex]. this resource contains auction records for different types of art. prices are hammer prices, exclusive of transaction costs. historically, the art sales index, just like many other databases, has not included buy-ins (i.e., items that do not reach the reserve price and remain unsold). although the first sales in the art sales index date from the beginning of the s, data are unavailable or sparse in many years until the second half of the s. therefore, we start our analysis in , the first year for which we have more than , observations. (unfortunately, however, for the data coverage is limited, with only some of the highest priced sales included.) the art sales index only includes london sales until the late s, but it has an exhaustive worldwide coverage afterwards. the most recent auction records available for this study are from the autumn auctions of . our final data set consists of , , sales; about % of these transactions concern oil paintings, with the remainder split roughly evenly between watercolors and drawings. the artist with the highest numbers of sales ( , ) is pablo picasso. the magnitude of our database enables us to draw a complete picture of the price formation and the returns in the art market, in contrast to most previous studies which are based on more selective samples. we translate all nominal prices in our data set to prices in year usd, using the cpi as a measure of inflation. in real terms, the most expensive transaction is ‘portrait du dr. gachet’ by vincent van gogh, which sold for million usd in may at christie's new york. (in nominal prices, it is ‘garçon à la pipe’ by pablo picasso, which was auctioned off for million usd in may at sotheby's new york.) while such high-profile sales attract ample attention, the average price level is much lower. the mean (resp. median) sales price over all observations for is , usd (resp. , usd). goetzmann ( ) argues that survivorship could cause upward bias in the estimation of art returns, since artists who “fall from fashion” are typically not traded. the impact of this bias on our results may be rather small. first, as goetzmann ( ) points out himself, the rate of artist obsolescence is relatively low. second, in contrast to previous work, we do not require a work of art to trade twice and/or to sell at a large auction house. our sample thus also includes many sales of less popular artists at smaller auction houses at any point in time (especially after ). finally, pieces that are donated to museums after a substantial increase in an artist’s fame – or items that are sold through private transactions in the early part of artists’ careers – are not observed at auction either (goetzmann, ; mei and moses, ), partially offsetting the upward bias. nevertheless, our return estimate should probably still be considered as an upper bound on the rate of return (before transaction costs) realized by art investors over our time frame. b. variables our hedonic regressions include a number of variables that capture the characteristics of the artist, of the work, and of the sale. the descriptive statistics for these hedonic variables are presented in table . [insert table about here] first, in addition to artist dummies capturing each artist’s uniqueness, we consider the following exogenous reputational measure: textbook dummy. we manually check which of our artists were included in several editions of the classic art history textbook ‘gardner’s art through the ages’ ( , , , , and ). in total, of our artists are listed in at least one edition. the dummy variable textbook equals one if the artist was featured in the edition of – or the last edition prior to – the year of sale. two other characteristics related to the artist’s career are included in the late-twentieth-century movement- specific models (cf. section iv.e), but not in our general models, as they could potentially pick up price differences between various eras or movements: exhibition dummy. the variable exhibition equals one once the artist has been represented at documenta in kassel. inclusion in this prestigious exhibition evidences an artist’s rise to fame. in total, of our artists were represented at one of the eleven exhibitions between and . dead artist dummy. it is often assumed that prices for art works increase after the death of an artist. the dummy variable deceased, which equals one if the sale occurs subsequent to the artist’s death, should capture this effect. second, we also consider a range of price-determining variables that capture the attribution and authenticity, the medium, the size, and the subject matter of the work of art: attribution dummies. attribution can be an important factor influencing the price of art objects, especially of older works. different levels of attribution are used in the auction world: attributed (to), studio (of), circle (of), school (of), after, and (in the) style (of). about % of the observations in our sample carry such an attribution. authenticity dummies. more than half of the art works is signed, while about one third is dated. medium dummies. we introduce dummies for the different medium categories: oil, watercolor (including gouaches), and drawing. size. the height and width in inches are represented by height and width (with squared values height_ and width_ ). the average work has a height and a width of about inches ( cm). topic dummies. the subject matter can significantly affect the aesthetic appreciation of art objects. we therefore categorize the works in different topic groups based on the first word(s) of the title. we create eleven categories, based on the search strings listed in appendix b: abstract, animals, landscape, nude, people, portrait, religion, self-portrait, still_life, untitled, and urban. furthermore, we create a dummy study that equals one if the title contains the words “study” or “etude”. the largest categories are portraits and landscapes. third, we include dummies that indicate the timing of the sale, and the reputation and location of the auction house: month dummies. since important sales are often clustered in time, we include month dummies. the busiest months are may, june, november, and december. auction house dummies. we make a distinction between different fine art auction houses that have been important throughout our sample period. for sotheby’s and christie’s, we introduce dummy variables for their london, new york, and other sales (e.g., soth_london, soth_ny, and soth_other). together, these two institutions are responsible for about half of all sales in our sample. for two other big british auction houses, bonhams and phillips, we make a distinction between their london sales rooms and other activities (e.g., bon_london and bon_other). we also create two dummies to account for the sales by important european and american auction houses (auction_european and auction_american) – see appendix c. iv. the returns on art a. baseline indices table shows the parameter estimates of the hedonic variables for our baseline model. eq. ( ) is estimated using ordinary least squares (ols) and the dependent variable is the natural log of the real price in usd. for , , sales we have complete information on all hedonic characteristics presented in the previous section. because of the very large number of observations, nearly all coefficients are statistically highly significant. hence, we focus on economic significance as well: table shows the “price impact” of each hedonic variable, which can be proxied by taking the exponent of the coefficient, and subtracting one. it is important to note that the variables are in most cases picking up otherwise unobservable differences in quality, and that the regression coefficients thus reflect correlation instead of causality. for example, works sold at sotheby’s or christie’s mainly catch higher prices because of their high attractiveness, not necessarily because of auction house certification. [insert table about here] table reveals that works are on average priced . % higher after the inclusion of the artist in an important art history reference book. also the strength of the attribution has an important effect on the price of an art object. whenever an attribution dummy comes into play, the price level drops by more than %. not surprisingly, larger discounts are recorded for works that are “in the style of” or “after” a master than for “attributed” or “studio” works. we also observe that signed and dated works carry higher prices: a signature increases the price by as much as % on average, while a date adds almost % in value. works on paper are priced lower than oil paintings, and drawings are less valuable than watercolors. furthermore, prices increase with size, up to the point that the work becomes too large, as indicated by the negative coefficients on the squared terms. regarding the topic dummies, there are significant discounts associated with studies and portraits, while self-portraits trade at a premium. the coefficients on our month-of-the- year dummies confirm that the most expensive auctions are clustered at the ends of the spring and the autumn. finally, the highest prices are paid at the main offices of sotheby’s and christie’s. based on the coefficients on the time dummies and the variance of residuals in each period, we construct both an uncorrected art price index Π, and a price index Π* that corrects for log transformation bias. the results are reported in table ; the price levels in are standardized to . as mentioned before, the coverage of the data is very selective for the year , so we geometrically interpolate index values for that year. (previous studies showed very small price movements in .) table indicates that the index values have high statistical precision. in most cases, the standard deviation on the regression coefficient is around . , which implies tight confidence intervals around each index value. figure graphically depicts the evolution of the indices over our time frame, and compares them to the evolution of deflated average and median prices in our data set. [insert table and figure about here] the corrected price index in figure illustrates that, in boom periods, prices can increase very fast: they more than tripled in real terms between and . the yearly increase in prices between and exceeded %. however, prices also rapidly decreased after , and no large changes in price levels occurred between the mid- s and the first years of the s. in the most recent art boom period of - , the annual real price appreciation averaged . %. the figure documents that an index based on average or median prices would overestimate the volatility of prices, because of the lack of control for quality differences over time. indeed, a key contribution of this paper is to disentangle changes in market composition from those in heterogeneity-controlled price levels. at the same time, however, the average and median series serve as a check on the order of magnitude of the overall price appreciation (at least over the last two-three decades, when the coverage of the data set is no longer expanding notably). figure also illustrates the quantitative importance of the correction for the log transformation; while the end-of-period index values are very similar, we observe marked deviations between Π and Π* over some periods. annualized (i.e., geometric average) returns are reported in panel a of table . we focus on the corrected price index. on average, art has appreciated at a yearly real rate of . % between and . over the last years, the geometric mean real return is somewhat higher ( . %). the nominal equivalents (not reported), obtained by correcting the index for the year-to-year changes in the cpi series, are . % ( - ) and . % ( - ). these numbers are substantially below the return estimates reported in goetzmann ( ) or mei and moses ( ) for the periods in common. for example, over the period - , mei and moses ( ) report an annualized nominal return of . %, while our index appreciated by . % on an annual basis – a difference of over %. [insert table about here] table also reports standard deviations of the time series of annual returns. for our corrected index, the standard deviation over the full time frame is slightly above %. however, we will later note that this number still underestimates the true riskiness of art investments (cf. section v). b. robustness checks we now check the quantitative robustness of our baseline results. first, we repeat our analysis using a number of different set-ups: (i) excluding the topic dummies (as these may capture the subject matter rather imprecisely), (ii) excluding the more than , artists with fewer than sales (as these artists are less liquid), and (iii) excluding minimalism & contemporary art (as selection and survivorship issues may be more of a concern for more recent artists). panel b of table shows the uncorrected real return estimates for - and - , which can be compared to the performance of price index Π, as shown in panel a. our estimates do not change substantially, with annualized price appreciations over the period - that differ by less than . % from those reported earlier. second, a potential problem with the hedonic approach is that coefficients are constrained to be stable across the whole sample window. this is a strong assumption as shadow prices of hedonic characteristics (i.e., tastes) may change over time. an adjacent-period model can mitigate this problem: by dividing the sample in subperiods, it enables the hedonic coefficients to fluctuate (triplett, ). we apply this method to our data set by performing a separate hedonic regression for every two consecutive years since (and then chain-linking our returns). we restrict our analysis to the second half of our time frame, because the methodology would underestimate the returns over the full time frame due to the expansion of coverage by the database over the first - years. the adjacent-year model generates an uncorrected return estimate ( . %) that is very similar to the one we obtained from the pooled data, lending further support to our benchmark index. third, the main advantage of rsr is that is controls for the uniqueness of each work. also, in contrast to a hedonic price index, it can be thought of as an investable index, at least in theory. unfortunately, our data set does not uniquely identify each artwork – let alone each repeated sale. yet, we aim to identify multiple transactions of the same item indirectly. we consider two items as being identical if they are from the same artist (not from a pupil or follower), have the same dimensions, carry the same title (but not “untitled” or “composition”), are of the same medium, and do not differ with respect to the presence of a signature or date. strikingly, this reduces the data set from . million individual transactions to , ‘repeat sales’ with a holding period of at least a year. for similar reasons as before – an rsr over the full sample would underestimate average returns because of the focus on higher-priced items in the first half of our time frame – we look at the , transactions between and . (this number compares favorably to the size of the databases used in previous repeat-sales studies.) in line with goetzmann ( ) and mei and moses ( ), we apply a three-stage estimation procedure on our sample of repeat sales, based on case and shiller ( ). in a first step, we regress returns on a matrix (containing a row for each item and a column for each time period) with dummy variables indicating the holding period of each item, using ols. in a second stage, we regress the squared residuals from the first step on an intercept and the time between sales. in a third step, we redo the rsr, using weighted least squares, with the fitted squared residuals as weights. the last line of panel b of table shows that, over the time frame under consideration, the rsr implies an average annual increase in the geometric mean price of . %, compared to . % for the (uncorrected) hedonic regression index. the standard deviation is only slightly higher than before. the correlation between the repeat-sales returns and the hedonic returns (not reported) is . . c. quantile regressions despite some work on the “masterpiece effect” – which examines the question whether more expensive art out- or underperforms the overall market (e.g., pesando, ; mei and moses, ) – prior literature has not systematically explored the potential variation of returns across price brackets. this is surprising, given that the art market is likely to be segmented for a number of reasons. first, art is indivisible, and therefore small investors are generally not able to invest in higher-end works. second, wealthy individuals may be less tempted to buy in the lower-end of the market, where works do not signal the same social status (mandel, ). third, the more expensive parts of the market may be more prone to speculation. the distribution of returns may thus be skewed over and above a potential masterpiece effect. in such a setting, quantile regressions may be particularly useful (zietz et al., ; scorcu and zanola, ). while ols regressions provide estimates for the conditional means only, non-linear quantile regressions can characterize the entire distribution of the dependent variable (koenker and hallock, ). we estimate price trends for the percentiles . , . , . , . , and . , using the adjacent-year set- up outlined before. (we split our sample in subperiods to avoid that the hedonic coefficients measure variation in premiums or discounts across time rather than across price brackets). we denote the price indices by q , q , etc. we show the results, again since , in panel c of table and in figure . an interesting pattern emerges. the low performance of q is particularly striking: it has an annual growth rate of only . %, compared with . % for q (i.e., the constant-quality median price level). over the last years, prices have gone up more in the higher price brackets. for example, for q , we record an annualized return of . %. paired-sample t-tests on the return series (not reported) show that the difference in (arithmetic) average return between q and any of the other quantile series is statistically significant at the . level. the outperformance of the higher quantiles is mainly due to strong price rises in times of increasing demand for art. this finding seems in line with “superstar economics”. the higher as with the hedonic regression, the rsr implies an index that is related to the geometric mean price in each period. goetzmann ( ) proposes to correct for log transformation bias by adding half of the cross-sectional variance of the returns in each period to the estimated coefficient, where this variance is estimated in the second step of the case- shiller method. however, goetzmann and peng ( ) argue that the nature of the bias due to the log transformation is generally not uniform through time. there is also a danger of misspecification of the error structure (meese and wallace, ) which may lead to an overestimation of the relevant correction term. since we are mainly interested in testing the robustness of our baseline index to a change in methodology, we compare the pre-correction indices to each other; they should give similar results. in rosen ( ), a small number of superstars earn large amounts of money, and increases in demand make the earnings distribution ever more skewed. a condition is that there is “imperfect substitution among quality average growth and higher volatility of the upper price range can also be associated with increases in both income inequality (goetzmann et al., ) and the income cyclicality of high-income households (parker and vissing-jorgensen, ), although we do not formally test these hypotheses in this paper (because of lack of a sufficiently long time series). in contrast, at first sight, the results seem at odds with the finding of mei and moses ( ) that masterpieces underperform – an issue that we turn to next. [insert figure about here] d. the performance of “masterpiece” and “value” portfolios the quantile regression results shows that prices have generally gone up more for high-value items. to further examine the profitability and riskiness of buying high-end art, we estimate the historical performance of two different investment strategies, based on our repeat-sales data. first, we consider a “masterpiece” strategy: we ‘buy’ in year t all auctioned works by the artists that were most expensive over years t- and t- (as measured by an adjacent-period hedonic regression model over those years). this strategy comes close to how other authors have examined the masterpiece effect, although we do not select works endogenously on realized transaction prices. second, we implement a “value” strategy: we buy in year t all observed works by the least expensive artists over t- and t- that were nevertheless included in the art history textbook described earlier at the start of year t- . such a strategy could exploit fluctuations in taste, or a lag in appreciation by the market relative to the recognition of the artist’s art-historical significance. (of course, the items included in this portfolio are in general still expensive compared to the overall sales distribution.) in both cases, we apply the rsr methodology to estimate returns; in other words, we ‘sell’ whenever the owner sold in practice. the results are shown in panel d of table , and compared to our earlier constructed rsr index in figure . [insert figure about here] we find no evidence of underperformance of a “masterpiece” strategy, which is not inconsistent with our quantile regressions, but stands in contrast to mei and moses ( ). the described strategy yields an annualized growth in price levels of . %, compared to . % for our earlier constructed rsr index. the differentiated goods”. this is certainly the case in the art market: ten mediocre works do not add up to a single masterpiece. in a recent paper, gyourko et al. ( ) rely on superstar economics to rationalize why the gap in house prices between “superstar cities” and less attractive locations keeps increasing over time; the authors note that “living in a superstar city is like owning a luxury good”. mei and moses ( ) and ashenfelter and graddy ( ) argue that idiosyncratic overbidding and mean reversion could be one explanation for the seemingly negative effect in studies that identify masterpieces based on transaction prices. goetzmann ( ) provides an alternative explanation: if only larger auction houses are taken into account, expensive items that drop in value are more likely to be included in the sample than lesser-quality works that underperform. of course, the relative performance of masterpieces may also vary over time, for example if it depends on evolutions in aggregate demand or the income distribution (cf. supra). “masterpiece” strategy realized strikingly high returns in the boom in the late s (when indeed “blue chip” art was very much in favor), but lost much in the subsequent bust. for the “value” strategy, we record an annualized return of . %; it has performed notably well since the mid- s. both high-end strategies thus have end-of-period index values above those for the overall sample, although the outperformance is not statistically significant at the traditional levels. the (unreported) p-value of a t-test on the difference between the “value” returns and the benchmark returns is . . e. indices per medium and per movement we now return to our baseline hedonic model and repeat the hedonic regression analysis on three complementary subsamples of our data set: oil paintings, watercolors, and drawings. the coefficients on the hedonic variables (not reported) are in line with the previous results. although the trends are similar across the different types of art, we find faster price increases for oil paintings. in real terms, watercolors and drawings were on average still priced lower in than in and . panel e of table reports the (corrected) returns over the different time frames. over the last half century, prices for oil paintings have appreciated at a yearly average real rate of . %, while watercolors and drawings have increased by . % and . % annually. oil paintings have strongly and significantly outperformed works on paper in the second half of our time frame – a finding that is related to the discrepancies in returns between price categories reported before. the lower performance of art items other than paintings is also consistent with pesando and shum ( ), who find an average real return on prints of . % between and . finally, we run a separate hedonic regression for each movement, based on the classification of each artist. we add the variables exhibition and deceased to the models for the three most recent art movements (abstract expressionism, pop, and minimalism & contemporary). most artists of these movements have been active over our time frame, which will enable a correct measurement of exhibition and death effects. we find that exhibition is significantly positive in the abstract expressionism and minimalism & contemporary set-ups; in the latter model we also observe a clearly positive death effect (not reported). in general, the results on the other hedonic characteristics are in line with the earlier findings, although there is some variation in the coefficients on the topic dummies (e.g., a premium is paid for nudes only in pop) and on the auction house dummies (e.g., auctions at the large continental european houses generate premiums for the earliest art movements). the average yearly real returns for the different art movements since and since are also reported in panel e of table . since , the indices have increased by between . % and . % on average per year. between and , only the post- war art movements abstract expressionism, pop, and minimalism & contemporary have shown real price appreciations of more than % per annum, on average. however, the standard deviations show that these movements have also been the more volatile ones. romanticism, realism, impressionism & symbolism, and fauvism & expressionism record mean appreciations of less than % over the same time frame. the indices for three art movements from different time periods (rococo; cubism, futurism & constructivism; and pop) are plotted in figure from onwards. the figure confirms that a post-war art movement like pop has been more profitable – the outperformance is statistically significant at the . level – but is also more risky. [insert figure about here] v. comparison of investment performance and correlation with other asset classes we want to compare the performance of art investments to that of other assets. however, we first need to address the underestimation of risk by our hedonic indices. since our methodology aggregates sales information per calendar year, our returns will suffer from spurious first-order autocorrelation and have understated standard deviations. we can unsmooth our baseline index Π*, a technique originated in the real estate literature, but later also applied to collectibles (e.g., campbell, ; dimson and spaenjers, ). based on working ( ), we can calculate that taking a yearly average of daily prices induces spurious first-order serial correlation in the hedonic coefficients of about . . we therefore re-estimate our standard deviations, removing this spurious autocorrelation from the return series. over the period - , the standard deviation of our desmoothed art index is now equal to . % (instead of . %). over the second quarter century, the standard deviation rises less sharply, from . % to . %. we collect data from global financial data on indices measuring total returns on u.s. t-bills, -year u.s. government bonds, dow jones corporate bonds, the gfd global index for government bonds, s&p stocks, the gfd world index for equity, gold prices, and the crb commodity price index. we borrow data on residential real estate prices in the u.s. from shiller ( ); unfortunately, commercial real estate price indices have only been available for shorter time periods. panel a of table shows the average yearly real returns and volatilities calculated over the periods - and - . the same table also presents the ex-post (arithmetic) sharpe ratios, using the returns on t-bills as the risk-free rate. [insert table about here] over the longer time frame, the art index clearly underperforms stocks. the s&p and the gfd global equity index have appreciated at average real rates of . % and . %, respectively, while our art index increased by . % annually over the same period. the reward-to-variability, as measured by the sharpe ratio, is higher for stocks and corporate bonds than for art. the art index has a higher average return even these new numbers are still a lower estimate of the true riskiness of art investments, for two reasons. first, the standard deviations reported here refer to the aggregate art market; panel d of table made clear that the volatility of most art portfolios is likely to be higher. second, our analysis does not take into account buy-ins. if reserve prices in the art market follow recent sales prices, this implies a return measurement bias when the market reverses (goetzmann and peng, ): returns may be underestimated (resp. overestimated) in boom (resp. bust) periods. since than both government bond indices, but the sharpe ratios only surpasses that of u.s. government bonds. nevertheless, compared to the other tangible assets in table (gold, commodities, and real estate), art does relatively well. over the shorter time frame (since ), the risk-return profile of art only compares favorably to that of other real asset classes. our comparison does not take into account differences in transaction costs, which are high for art investments. for most of our time frame, auction houses charged buyer’s premiums and seller’s commissions of around % (pesando, ; ashenfelter and graddy, ). however, in recent years, while important consignors have sometimes been able to obtain lower commission rates, the buyer’s premium has grown to around % for many smaller purchases. the large transaction costs emphasize the need for long holding periods in collectibles markets (dimson and spaenjers, ). moreover, art buyers have to take into account storage and insurance costs. we now turn to the correlations between the asset categories. panel b of table shows the correlation matrix of real returns for the - time frame. the correlations between our art index on the one hand and the gold, commodity, and real estate price indices on the other are . or higher. in contrast, we find very little comovement between art and financial assets. yet, additional (unreported) analysis shows correlations of art returns with lagged equity returns of . (s&p stocks) and . (global stocks). this suggests that wealth effects may drive art prices – something we examine in more depth in the next section. vi. explaining the returns on art art is ultimately a durable luxury consumption good, and consumption indeed seems to dominate the art purchase decision for a representative agent (mandel, ). the fundamental value of a work of art can thus be thought of as the present value of all future flows of consumption services. since supply is inelastic, the market price of these consumption flows will be determined by the strength of demand in each period. the importance of investment income for wealthy households, together with the discretionary nature of luxury consumption, may then induce positive correlation between art prices and financial asset values (aït-sahalia et al., ). previous literature (e.g., hiraki et al., ; goetzmann et al., ) has indeed found a strong relation between stock prices and art prices. in line with this work, in column ( ) of table , we regress our art returns on same-year and lagged global stock market returns over the period - . below each coefficient, we report newey-west standard errors that control for heteroskedasticity and autocorrelation up to two lags. adjusted r-squareds are reported at the bottom. the results confirm that stock returns significantly affect art price growth rates. in unreported analysis, we also control for changes in top incomes (using updated u.s. data from piketty and saez ( ), available from emmanuel saez’ webpage), real interest rates, and equity market sentiment (baker and wurgler, ), but this does not materially change our results. [insert table about here] to further examine the role of consumer demand, we add in column ( ) a variable that measures whether high-income (upper third) consumers think it is a good time to purchase “major household items”. (ludvigson ( ) notes that “there is some evidence that consumer confidence surveys reflect expectations of income and non-stock market wealth growth”.) the information is taken from the university of michigan’s survey of consumers, and we use the data for december of the previous year. the measure has been standardized to have zero mean and unit variance. we find that consumer sentiment strongly significantly affects art returns. we also see an increase in adjusted r-squared from . to . . the results in columns ( ) and ( ) of table highlight the importance of consumption demand. however, they cannot fully explain the pattern of art markets booms and busts that we have witnessed over the last decades. this may be because the fundamental value of art, as defined before, is hard to grasp. combined with the impossibility of short-selling, this uncertainty implies a potential role for art buyer sentiment, which could be defined as unjustified optimism (or pessimism) about future resale values. furthermore, because auctions are held infrequently, sentiment may only slowly exert pressure on observed aggregate price levels. we thus expect high sentiment to be followed by price appreciations – at least in the short run – rather than by low returns as is the case in more liquid financial asset markets (baker and wurgler, ). we propose three proxies for art buyer sentiment which can be measured by the end of each year (so that they can be related to price levels in the year starting immediately after). a first factor is the year-on- year change in fourth-quarter sales volume at sotheby’s and christie’s (london). baker and stein ( ) argue that in markets with short-sale constraints liquidity can proxy for sentiment. moreover, they suggest that the “liquidity-as-sentiment approach” is particularly relevant for “real” asset markets. our second variable equals the rate of items sold (and thus not bought in) at the impressionist and/or modern art evening auctions in the fall of each year (since ) in new york. these high-profile auctions are considered a barometer for the market, and buy-ins at these sales are widely commented upon in the press. we proxy for the sales rates by dividing the number of observed transactions by the maximum lot number for each auction. for our third proxy, we turn to the historical archives of the economist. we look up all articles dated between and which mention “art market”, “art prices”, or “art auctions”. we read each article to verify that it is indeed about the state of the art market, or about art investment. we then analyze the content of each of the selected articles using a software package called general inquirer. general inquirer counts the number of words belonging to certain categories in a text, and is also used by tetlock ( ) in his analysis of wall street journal columns. in each year, our measure of sentiment is the relative use of “positive outlook” versus “negative outlook” words in the latest article of the year, using the built-in dictionaries of the software. our main sentiment measure is then the first principal component of these three sentiment proxies (which have positive pairwise correlations of between . and . ). applying a principal components procedure reduces the idiosyncratic noise in each individual measure (baker and wurgler, ). we show the evolution of our standardized sentiment measure since in figure . sentiment was negative in the early s, s, and s, and generally positive in the second half of the s and the mid- s. [insert figure about here] in column ( ) of table , we regress the returns on art on the lagged sentiment measure, controlling for same-year and lagged global equity returns and the lagged consumer confidence measure, over the period - . the lagged stock return variable is still positive but loses significance at the traditional levels. in line with expectations, we find a positive impact of art market sentiment that is statistically significant at the . level. this strongly suggests that time-varying optimism about art investment impacts art pricing. unreported analysis shows that pop and minimalism & contemporary art, which may be harder to value, are more sensitive to changes in art buyer sentiment. vii. conclusion many collectors are acutely attuned to the financial value of their assets (burton and jacobsen, ). moreover, investors are increasingly turning to collectibles markets to diversify their portfolios. this underlines the importance of an accurate measure of the financial returns to art. therefore, in this paper, we have investigated the price determinants and historical investment performance of art, by applying an extensive hedonic regression framework to a data set of more than one million paintings and works on paper. our hedonic art price index indicates that art prices have increased by a moderate . %, annually, in real usd terms between and . this return estimate is lower than that reported in previous papers that used smaller samples of high-quality paintings sold at top auction houses. during art market booms, however, prices can skyrocket. for example, between and , our index shows a real return of . % per year. we also document larger price appreciations at the upper end of the market, and variation in average returns across mediums and movements. in general, art’s risk-return profile is much less attractive than that of financial assets, even before transaction costs. finally, regression results show that art price cycles are determined by both luxury consumption demand and variation in art market sentiment. appendix a – compilation of list of artists we start by consulting grove art online [http://www.oxfordartonline.com], a database published by oxford university press that contains all articles of the -volume ‘the dictionary of art’ ( ) as well as ‘the oxford companion to western art’ ( ). we select all , individual artists from the categories ‘graphic arts’, ‘painting and drawing’, and ‘printmaking’. we subsequently expand our set of artists by means of another online database, artcyclopedia [http://www.artcyclopedia.com]. this raises the number of artists to , . we then compose a list of thirteen art movements: medieval & renaissance; baroque; rococo; neoclassicism; romanticism; realism; impressionism & symbolism; fauvism & expressionism; cubism, futurism & constructivism; dada & surrealism; abstract expressionism; pop; and minimalism & contemporary. when possible, we classify our artists into one of these categories, based on the ‘styles and cultures’ from grove art online and ‘art movements’ of artcyclopedia. we can put , artists into at least one art movement. next, we expand our data set in two more ways, to correct for the possible underrepresentation of modern and contemporary art. we compare the index of the influential book ‘modern art’ (britt, ) to our data set and add modern artists to our list (with classification). the book also enables us to assign another artists not yet classified to a specific art movement. next, in order to have a representative and up-to-date sample of contemporary artists, we consult wikipedia [http://en.wikipedia.org/wiki/list_of_contemporary_artists] in april . we can add artists, bringing our list to , artists in total; other artists can now be classified in minimalism & contemporary. finally, we check for pseudonyms and different spellings of all artists’ names. appendix b – titles and topics we use the first word(s) of the title to classify works in topic categories. most titles in our database are in english, but we also include french keywords in our analysis. we avoid search strings that can be used in different contexts. sometimes we only search for titles no longer than one word or in which the word is followed by a space (e.g., “cat_”) to avoid misclassifications due to longer words with identical first characters (e.g., “catholic”). these are the topic categories, along with their search strings: abstract (“abstract”, “composition”), animals (“horse”, “cheval”, “chevaux”, “cow_”, “cows”, “vache”, “cattle”, “cat_”, “cats”, “chat_ “, “dog_”, “dogs”, “chien”, “sheep”, “mouton”, “bird”, “oiseau”), landscape (“landscape”, “country landscape”, “coastal landscape”, “paysage”, “seascape”, “sea_”, “mer_”, “mountain”, “river”, “riviere”, “lake”, “lac_”, “valley”, “vallee”), nude (“nude”, “nu_”, “nue_”), people (“people”, “personnage”, “family”, “famille”, “boy”, “garcon”, “girl”, “fille”, “man_”, “men_”, “homme”, “woman”, “women”, “femme”, “child”, “enfant”, “couple”, “mother”, “mere_”, “father”, “pere_”, “lady”, “dame”), portrait (“portrait”), religion (“jesus”, “christ_”, “apostle”, “ange_”, “angel”, “saint_”, “madonna”, “holy_”, “mary magdalene”, “annunciation”, “annonciation”, “adoration”, “adam and eve”, “adam et eve”, “crucifixion”, “last supper”), self-portrait (“self-portrait”, “self portrait”, “auto-portrait”, “autoportrait”), still_life (“still life”, “nature morte”, “bouquet”), untitled (“untitled”, “sans titre”), urban (“city”, “ville”, “town”, “village”, “street”, “rue”, “market”, “marche”, “harbour”, “port_”, “paris”, “london”, “londres”, “new york”, “amsterdam”, “rome_”, “venice”, “venise”). appendix c – important european and american auction houses the auction_european category includes all sales by: lyon & turnbull (scotland), francis briest / artcurial briest (france), ader, picard & tajan / ader & tajan / tajan (france), bruun rasmussen (denmark), dorotheum (austria), koller (switzerland), lempertz (germany), neumeister (germany), finarte (italy), bukowskis (sweden), stockholms auktionsverk (sweden). the auction_american category includes all sales by: butterfields (until ), swann auction galleries, skinner, doyle new york, freeman’s, leslie hindman. references aït-sahalia, y., parker, j., yogo, m. “luxury goods and the equity premium.” journal of finance ( ), - . agnello, r., pierce, r. “financial returns, price determinants, and genre effects in american art investment.” journal of cultural economics ( ), - . anderson, r. “paintings as an investment.” economic inquiry ( ), - . artprice. art market trends . artprice.com ( ). ashenfelter, o., graddy, k. “auctions and the price of art.” journal of economic literature ( ), - . baker, m., stein, j. “market liquidity as a sentiment indicator.” journal of financial markets ( ), - . baker, m., wurgler, j. “investor sentiment and the cross-section of stock returns.” journal of finance ( ), - . baumol, w. “unnatural value: or art investment as floating crap game.” american economic review (aea papers and proceedings) ( ), - . britt, d. 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examining the pros and cons of allowing passion into your portfolio.” the wall street journal europe, the journal report: wealth adviser, september ( ). working, h. “note on the correlation of first differences of averages in a random chain.” econometrica ( ), - . zietz, j., zietz, e., sirmans, g. “determinants of house prices: a quantile regression approach.” journal of real estate finance and economics ( ), - . table – descriptive statistics hedonic variables table displays the descriptive statistics for the hedonic variables used in this study. textbook is a dummy variable that equals one if the artist was included in the last edition of ‘gardner’s art through the ages’ ( , , , , or ) prior to the sale. exhibition is a dummy variable that equals one once the artist has exhibited at the documenta art exhibition in kassel, germany. deceased equals one in case the artist is dead at the time of the sale. the attribution dummies attributed, studio, circle, school, after, and style equal one if the auction catalogue identifies the work as being “attributed to” the artist, from the “studio” of that artist, from the “circle” of the artist, from the artist’s “school”, “after” the artist, or “in the style of” the artist, respectively. the authenticity dummies signed and dated take the value of one if the work carries a signature of the artist or is dated, respectively. the medium dummies oil, watercolor, and drawing indicate whether the work is an oil painting, a watercolor (or a gouache), or another work on paper. the variables height and width measure the height and the width of the work in inches. the topic dummies are based on the first word(s) of the title of the work (cf. appendix b). the month dummies indicate the month of the sale. the auction house dummies soth_london, soth_ny, soth_other, chr_london, chr_ny, chr_other, bon_london, bon_other, phil_london, and phil_other equal one if the sale takes place at sotheby’s london, sotheby’s new york, another branch of sotheby’s, christie’s london, christie’s new york, another branch of christie’s, bonhams london, another office of bonhams, phillips london, or another sales room of phillips, respectively. auction_european and auction_american are dummy variables that equal one if the sale takes place at a large continental european or a large american auction house, respectively (cf. appendix c). for each variable, we report the number of observations (n), the mean, and the standard deviation (s.d.). for dummy variables, we also show the number of zeros and ones. n mean s.d. artist characteristics textbook , , . . , , exhibition , , . . , , deceased , , . . , , work characteristics attribution dummies attributed , , . . , , , studio , , . . , , , circle , , . . , , , school , , . . , , , after , , . . , , , style , , . . , , , authenticity dummies signed , , . . , , dated , , . . , , medium dummies oil , , . . , , watercolor , , . . , , drawing , , . . , , size variables height , , . . width , , . . topic dummies study , , . . , , , abstract , , . . , , , animals , , . . , , , landscape , , . . , , , nude , , . . , , , people , , . . , , , portrait , , . . , , , religion , , . . , , , self-portrait , , . . , , , still_life , , . . , , , untitled , , . . , , , urban , , . . , , , sale characteristics month dummies january , , . . , , , february , , . . , , , march , , . . , , april , , . . , , may , , . . , , june , , . . , , july , , . . , , , august , , . . , , , september , , . . , , , october , , . . , , november , , . . , , december , , . . , , auction house dummies soth_london , , . . , , soth_ny , , . . , , soth_other , , . . , , , chr_london , , . . , , chr_ny , , . . , , , chr_other , , . . , , , bon_london , , . . , , , bon_other , , . . , , , phil_london , , . . , , , phil_other , , . . , , , auction_european , , . . , , auction_american , , . . , , , table – baseline hedonic regression results table presents the baseline hedonic regression results. eq. ( ) is estimated using ols. the dependent variable is the natural log of the price in year usd. the descriptive statistics for the independent variables are shown in table . for each variable, we report the coefficient (β), the standard deviation (s.d.), and the price impact (i.e., the exponent of the coefficient minus one). the number of observations (n) and the r-squared (r ) are presented at the bottom of the table. β s.d. exp(β) - year dummies [included] artist characteristics artist dummies [included] textbook . . . % work characteristics attribution dummies attributed - . . - . % studio - . . - . % circle - . . - . % school - . . - . % after - . . - . % style - . . - . % authenticity dummies signed . . . % dated . . . % medium dummies oil [left out] watercolor - . . - . % drawing - . . - . % size variables height . . . % width . . . % height_ - . . - . % width_ - . . - . % topic dummies study - . . - . % abstract - . . - . % animals - . . - . % landscape - . . - . % nude - . . - . % people - . . - . % portrait - . . - . % religion - . . - . % self-portrait . . . % still_life . . . % untitled - . . - . % urban . . . % sale characteristics month dummies january [left out] february - . . - . % march . . . % april . . . % may . . . % june . . . % july . . . % august - . . - . % september - . . - . % october . . . % november . . . % december . . . % auction house dummies soth_london . . . % soth_ny . . . % soth_other . . . % chr_london . . . % chr_ny . . . % chr_other . . . % bon_london . . . % bon_other - . . - . % phil_london . . . % phil_other . . . % auction_european . . . % auction_american - . . - . % n , , r . table – baseline art price indices and art returns table presents the art price indices and returns for the baseline hedonic regression model detailed in table . for each year, we report the dummy coefficient (γ), the standard deviation (s.d.), the variance of the residuals (σ ), the uncorrected price index and return (Π and r), and the price index and return that are corrected for changes in price dispersion over time (Π* and r*) (cf. section iii). index values for are geometrically interpolated. year γ s.d. σ Π r Π* r* . . . - . . . . - . % . - . % . . . . . % . . % . . . . . % . - . % . . . . . % . . % . . . . . % . . % - - - . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . - . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . - . % . - . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . - . % . - . % . . . . - . % . - . % . . . . - . % . - . % . . . . - . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . - . % . . . . - . % . - . % . . . . - . % . - . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . - . % . - . % . . . . - . % . - . % . . . . - . % . - . % . . . . - . % . . % . . . . . % . . % . . . . - . % . - . % . . . . - . % . . % . . . . . % . . % . . . . . % . . % . . . . - . % . - . % . . . . - . % . - . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % . . . . . % . . % table – annualized returns for baseline indices, robustness checks, and extensions panel a of table presents the annualized (i.e., geometric average) returns and standard deviations (s.d.) over the periods - and - for the baseline art price indices detailed in table . it also shows the number of observations (n) included in the estimation. panel b shows the results for a number of robustness checks (cf. section iv.b). panel c repeats the adjacent-period hedonic model using quantile regressions (cf. section iv.c). panel d presents the rsr results for two different trading strategies (cf. section iv.d). panel e shows the return estimates (corrected for changes in price dispersion over time) for the different mediums and movements considered in this study (cf. section iv.e). n real returns - - mean s.d. mean s.d. panel a: baseline indices art price index Π , , . % . % . % . % art price index Π* , , . % . % . % . % panel b: robustness checks (compare to Π) drop topic dummies , , . % . % . % . % exclude artists < sales , . % . % . % . % exclude min. & cont. , , . % . % . % . % adjacent-period model - - - . % . % repeat-sales regression (rsr) , (x ) - - . % . % panel c: quantile regressions q , - - . % . % q , - - . % . % q , - - . % . % q , - - . % . % q , - - . % . % panel d: trading strategies (compare to rsr) “masterpiece” strategy , (x ) - - . % . % “value” strategy (x ) - - . % . % panel e: indices per medium and per movement oil , . % . % . % . % watercolor , . % . % . % . % drawing , . % . % . % . % medieval & renaissance , . % . % . % . % baroque , . % . % . % . % rococo , . % . % . % . % neoclassicism , . % . % . % . % romanticism , . % . % . % . % realism , . % . % . % . % impressionism & symbolism , . % . % . % . % fauvism & expressionism , . % . % . % . % cubism, futurism & constr. , . % . % . % . % dada & surrealism , . % . % . % . % abstract expressionism , - - . % . % pop , - - . % . % minimalism & contemporary , - - . % . % table – art versus other assets panel a of table displays the geometric mean real returns on art and other assets since and since . the real returns on art are based on our corrected price index Π*, and are shown in table . the return data for the financial assets, gold, and commodities come from global financial data. data for u.s. real estate come from shiller ( ). the panel also includes the standard deviation (s.d.) of the returns, and the arithmetic sharpe ratio (i.e., the arithmetic average excess return divided by its standard deviation). the standard deviations for art are based on a desmoothed return series (cf. section v). the return on t-bills is used as a proxy for the risk-free rate. panel b shows the pairwise correlations between the returns since . correlation coefficients that are significantly different from zero at the . level are displayed in bold. panel a: comparison of investment performance real returns - - mean s.d. sharpe mean s.d. sharpe art . % . % . . % . % . t-bills . % . % n.a. . % . % n.a. u.s. government bonds . % . % . . % . % . dj corporate bonds . % . % . . % . % . global government bonds . % . % . . % . % . s&p stocks . % . % . . % . % . global stocks . % . % . . % . % . gold . % . % . - . % . % - . commodities . % . % . . % . % . u.s. real estate . % . % - . . % . % . panel b: correlations of returns a rt t -b ill s u .s . g ov er nm en t b on ds d j co rp or at e bo nd s g lo ba l g ov er nm en t b on ds s& p st oc ks g lo ba l s to ck s g ol d c om m od iti es u .s . r ea l e st at e art . t-bills . . u.s. government bonds - . . . dj corporate bonds - . . . . global government bonds - . . . . . s&p stocks - . . . . . . global stocks . . . . . . . gold . - . - . - . - . - . - . . commodities . - . - . - . - . - . - . . . u.s. real estate . - . - . - . - . - . . . . . table – explaining the returns on art table presents the results of a linear regression of art returns on a number of independent variables, over the period - . below each coefficient, we report newey-west standard errors that control for heteroskedasticity and autocorrelation up to two lags. the real returns on art are based on our corrected price index Π*, and are shown in table . model ( ) only includes same-year and lagged global stock returns, from global financial data, as independent variables. column ( ) adds (lagged and standardized) data from the university of michigan’s survey of consumers on the attitude of high-income (upper third) consumers with respect to the purchase of “major household items”. model ( ) adds a newly constructed (lagged and standardized) art market sentiment measure, based on volume and buy-in rates at high-profile auctions, and on media reports (cf. section vi). the number of observations (n) and the adjusted r-squared (r ) are presented at the bottom of the table. ( ) ( ) ( ) dependent variable: real returns on art same-year global stock returns . . . ( . ) ( . ) ( . ) previous-year global stock returns . ** . * . ( . ) ( . ) ( . ) high-income consumer confidence . *** . ** ( . ) ( . ) art market sentiment . ** ( . ) n adjusted r . . . figure – hedonic price indices figure presents the baseline art price indices detailed in table . Π is the uncorrected price index, while Π* corrects for changes in price dispersion over time. the figure also includes the average and median real price for each year in our data set. figure – quantile regressions figure presents the art price indices that result from repeating the adjacent-period hedonic model using quantile regressions (cf. section iv.c). Π (uncorrected) Π* (corrected) average real price median real price q q q q q figure – trading strategies figure presents the index that results from applying an rsr to all item pairs that are considered to be repeated transactions (cf. section iv.b), and the art price indices for a “masterpieces” and a “value” trading strategy (cf. section iv.d). figure – indices per movement figure presents the (corrected) art price indices for three different movements: rococo; cubism, futurism & constructivism; and pop (cf. section iv.e). rsr masterpiece value , , , rococo cubism, futurism & constructivism pop figure – art market sentiment figure presents the end-of-year values for the art market sentiment measure used in this study. it is based on volume and buy-in rates at high-profile auctions, and on media reports (cf. section vi). it is standardized to have zero mean and unit variance. - - - adam and asthma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . is big beautiful? the continuing story of adam and asthma s t holgate, j w holloway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . role of adam in the development and progression of asthma t he gene encoding a disintegrin and metalloprotease (adam) was the first asthma susceptibility gene to be discovered by positional cloning. in families enriched with asthma, linkage analysis using microsatellite markers spaced , cm apart revealed a region on chromosome p that carried one or more asthma genes, achieving a maximum lod score (mls) of . at . cm. the addition of further markers at . cm increased the mls to . at . cm which further rose to . when bronchial hyperresponsiveness was included in the definition of asthma despite halving the sample size, thereby exceeding the threshold for genome wide significance. physical mapping, direct cdna selec- tion, and sequencing of dna cloned into bacterial artificial chromosomes (bacs) identified candidate genes. linkage disequilibrium mapping of single nucleotide polymorphisms (snps) on genes spanning the peak of linkage together with case-control and family based association analyses revealed that adam accounted for the linkage signal. several features of this initial report raised questions regarding the generali- sability of the results. firstly, although significant evidence for linkage was observed, this region on chromosome p had not been identified in previous genome wide screens in asthma. secondly, the initial publication did not have a truly independent replication sample. thirdly, no single snp demon- strated significant association in both the uk and us populations that made up the total sample when these were analysed separately. finally, no func- tional data regarding the role of asso- ciated snps in alteration of gene expression and/or function and in the development of asthma phenotypes were presented. since there have been a number of separate replication studies in diverse ethnic populations. the first by howard et al examined eight snps in the portion of adam reported in the original study to be associated with asthma in four unique asthma popula- tions comprising african american, us white, us hispanic, and dutch white populations. significant associations with at least one snp and asthma were found in each of the populations (p = . – . ) with multiple snps associating with asthma or its partial phenotypes in some of the populations. further replication has been reported in separate case-control and family based association studies in germany, korea, and japan. however, there are two published studies showing no evidence of association or weak association. it is therefore timely that, in this issue of thorax, blakey and colleagues report the result of a meta-analysis involving eight separate populations totalling cases and controls used in case-control association analysis and families used in transmission disequilibrium tests (tdts). in both types of analysis several snps were significantly associated with asthma. the important point the authors made is that, based on allele frequencies for the st+ g allele of . % in the asthmatic population and . % in the controls and an asthma prevalence of %, this snp would potentially contri- bute to , excess asthma cases in the uk population. what is important to point out is that most case-control and family based association studies looking for disease related genes in complex disorders are statistically underpowered and that far larger sample sizes are needed. part of the reason for this is the existence of genetic heterogeneity with any one gene varying in its influence over a disease phenotype between populations with differing genetic backgrounds and dif- fering environmental exposures. for example, natural selection may have acted on a disease gene haplotype differentially in different populations as recently described for the il- locus on chromosome q – . another example is the nod /card gene on chromosome which has been associated with crohn’s disease in some but not all populations. because a statistical association is not revealed in a particular population irrespective of size does not necessarily mean that the gene in question is not contributing to the phenotype, but the mode of its influence may be complex involving gene-gene or gene-environmental inter- actions. however, as the number of independent studies increases, it would be valuable to accrue the evidence systematically as was reported for link- age analysis for asthma on chromosome (the consortium on asthma genetics). with the recent establish- ment of the network of excellence for asthma and allergy (ga len), there is a unique opportunity to further develop meta-analyses for candidates such as adam . the study by blakey et al is an excellent example of the power of this approach. at present the snps that cause the dysfunction in adam predisposing to asthma are not yet clear, although several snps (t , f+ and st+ ) are coming through in a number of differ- ent studies as being associated with asthma. however, because of the very large degree of linkage disequilibrium between many snps in adam so far identified (possibly in excess of ), genetics alone is unlikely to cast much further light on the disease related variants although new analytical meth- odologies are being developed. some clues about how adam may influ- ence the asthma phenotype are emer- ging. in dutch patients with asthma who had regular lung function measure- ments made over years, the rare alleles of the snps s- , t- and t- of the adam gene were associated with a significant excess decline in baseline forced expiratory volume in second (fev ) of . – ml/year. these data imply a role for adam in airway wall remodelling which is known to contri- bute to chronic airflow obstruction in moderate to severe asthma. a second study conducted in infants born of allergic/asthmatic parents in northern england ( nac maas) has revealed posi- tive associations between snps of adam and increased airway resis- tance measured by plethysmography at age and again at age years, with the strongest effect seen in the homo- zygotes. these data support the idea that alterations in the expression or function of adam is in some way involved in impairing lung function in early life and, as a consequence, increas- ing the risk of asthma developing. the initial study as well as others have revealed some of the strongest associations when bronchial hyperre- sponsiveness (bhr) is incorporated into the asthma phenotype. the cellular provenance of adam mrna and editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ protein in being restricted to mesen- chymal cell types (fibroblasts, myofibro- blasts and smooth muscle) reinforces the view that this molecule is involved in the pathophysiology of bhr and airway remodelling rather than the immunological or inflammatory compo- nents of asthma. expression of full length adam in mammalian cell lines has shown that the metallopro- tease domain of adam is func- tional but the biological targets of the metalloprotease activity are as yet unknown. in cell based sheddase assays adam functioned as a negative reg- ulator of b-amyloid precursor peptide (app) cleavage and mediated some constitutive shedding of stem cell factor (scf, ckit ligand); however, the kinetics of these cleavage reactions would indi- cate that these two proteins are not the natural substrates. six alternatively spliced variants of adam in airway fibroblasts have recently been described including one putative secreted variant. ninety per- cent of adam mrna is retained in the nucleus and subtle differences in the composition of nuclear and cytoplasmic mrna indicate important events in both splicing and selecting of adam transcripts for processing into proteins. what is of great interest is that none of the six variants contain the metallopro- tease catalytic domain, suggesting pos- sible other key functions of the molecule—for example, in cell fusion and adhesion. there is still much to find out about this fascinating and complex molecule in relation to the development and progression of asthma. added to it are three further new asthma/allergy genes identified by positional cloning: pdh finger protein ii (phf ) on chromo- some q which encodes ny-ren- , a protein first described in patients with renal cell carcinoma; dipeptidyl dipti- dase (ddp ) on chromosome q ; and g protein-coupled receptor for asthma susceptibility (gpra) on chro- mosome p. for each of these genes, as for adam , determining normal functions and how these are disordered in asthma related alleles is the real future challenge. we are now entering the new research era of translational science and the rebirth of experimental medicine as a research focus. thorax ; : – . doi: . /thx. . authors’ affiliations . . . . . . . . . . . . . . . . . . . . . . s t holgate, j w holloway, allergy and inflammation research, division of infection, inflammation and repair, school of medicine, southampton general hospital, southampton so yd, uk j w holloway, division of human genetics, school of medicine, southampton general hospital, southampton so yd, uk correspondence to: professor s t holgate, allergy and inflammation research, mp , level d, centre block, southampton general hospital, southampton so yd, uk; sth@ soton.ac.uk references van eerdewegh p, little rd, dupuis j, et al. association of the adam- gene with asthma and bronchial hyper-responsiveness. nature ; : – . weiss st, raby ba. asthma genetics . hum mol genet ; :r – . howard td, postma ds, jongepier h, et al. association of a disintegrin and metalloprotease (adam ) gene with asthma in ethnically diverse populations. j allergy clin immunol ; : – . werner m, herbon n, gohlke h, et al. asthma is associated with single-nucleotide polymorphisms in adam . clin exp allergy ; : – . lee j-h, park h-s, park sw, et al. adam polymorphism: association with bronchial hyper- responsiveness in korean asthmatics. clin exp allergy ; : – . sakagami t, hasegawa t, yoshizawa h, et al. adam polymorphisms are associated with aspirin intolerant asthma in japanese population. am j respir crit care med ; :a . lind dl, choudhry s, ung n, et al. adam is not associated with asthma in puerto rican or mexican populations. am j respir crit care med ; : – . raby ba, silverman ek, kwiatkowski dj, et al. adam polymorphisms and phenotype associations in childhood asthma. j allergy clin immunol ; : – . blakey j, halapi e, bjornsdottir us, et al. contribution of adam polymorphisms to the population risk of asthma. thorax ; : – . cookson w. a new gene for asthma: would you adam and eve it? trends genet ; : – . ioannidis jp, ntzani ee, trikalinos ta, et al. replication validity of genetic association studies. nat genet ; : – . sakagami t, witherspoon dj, nakajima t, et al. local adaptation and population differentiation at the interleukin and interleukin loci. genes immun ; : – . arnott id, nimmo er, drummond he, et al. nod /card , tlr and cd mutations in scottish and irish crohn’s disease patients: evidence for genetic heterogeneity within europe? genes immun ; : – . vercelli d. genetics, epigenetics, and the environment: switching, buffering, releasing. j allergy clin immunol ; : – . lonjou c, barnes k, chen h, et al. a first trial of retrospective collaboration for positional cloning in complex inheritance: assay of the cytokine region on chromosome by the consortium on asthma genetics (coag). proc natl acad sci usa ; : – . bureau a, dupuis j, falls k, et al. identifying snps predictive of phenotype using random forests. genet epidemiol ; : – . jongepier h, boezen hm, dijkstra a, et al. polymorphisms of the adam gene are associated with accelerated lung function decline in asthma. clin exp allergy ; : – . bel eh. clinical phenotypes of asthma. curr opin pulm med ; : – . john s, jury fac, holloway j, et al. adam polymorphisms predict early-life lung function: a population based cohort study. am j hum genet ; : . simpson a, jury f, cakebread j, et al. manchester asthma and allergy study: polymorphisms in adam predict lung function at age years. j allergy clin immunol ; :s . umland sp, garlisi cg, shah h, et al. human adam messenger rna expression profile and post-transcriptional regulation. am j respir cell mol biol ; : – . garlisi cg, zou j, devito ke, et al. human adam : protein maturation and localization. biochem biophys res commun ; : – . zou j, zhu f, liu j, et al. catalytic activity of human adam . j biol chem ; : – . powell rm, wicks j, holloway jw, et al. the splicing and fate of adam transcripts in primary human airways fibroblasts. am j respir cell mol biol ; : – . cakebread ja, haitchi hm, holloway jw, et al. the role of adam in the pathogenesis of asthma. springer semin immunopathol ; : – . zhang y, leaves ni, anderson gg, et al. positional cloning of a quantitative trait locus on chromosome q that influences immunoglobulin e levels and asthma. nat genet ; : – . allen m, heinzmann a, noguchi e, et al. positional cloning of a novel gene influencing asthma from chromosome q . nat genet ; : – . laitinen t, polvi a, rydman p, et al. characterization of a common susceptibility locus for asthma-related traits. science ; : – . wills-karp m, ewart sl. time to draw breath: asthma-susceptibility genes are identified. nat rev genet ; : – . editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ no, hypoxia, and superoxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . nitric oxide, hypoxia, and superoxide: the good, the bad, and the ugly! r a dweik . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . a possible role for no in ards n itric oxide (no) is endogenously synthesised by nitric oxide synthases (nos) which convert l-arginine to l-citrulline and no. three nos isoforms (types i, ii and iii) have been identified and all of them are expressed in the human lung. – nos i (nnos) and iii (enos) are constitu- tively expressed in tissues and are dependent on increases in intracellular calcium for enzyme activation while nos ii (inos) is an inducible form that is calcium independent (table ). all nos isoforms require oxygen, nadph, fad, fmn, tetrahydrobiopterin, and calmodulin for activity. no is recog- nised to have a key role in virtually all aspects of lung biology and has been implicated in the pathophysiology of lung diseases. – it is involved in pulmonary neurotransmission, host defence and bacteriostasis, airway and vascular smooth muscle relaxation, pul- monary capillary leak, inflammation, mucociliary clearance, airway mucus secretion, and cytotoxicity. cellular sources of no in the lung include epithelial cells, endothelial cells of pulmonary arteries and veins, inhibi- tory non-adrenergic non-cholinergic neurones, smooth muscle cells, mast cells, mesothelial cells, fibroblasts, neutrophils, lymphocytes, and macro- phages. specifically, nos i is located in inhibitory non-adrenergic non-cholinergic neurones in the lung while nos iii is found in endothelial cells and the brush border of ciliated epithelial cells. nos ii is found in the epithelial cells of the airway. although nos ii may be induced in several types of cells in response to cytokines, endotoxin, or reactive oxygen species, it is continuously expressed in normal human airway epithelium at basal airway conditions. once produced, no is freely diffusible and enters target cells activating soluble guanylate cyclase to produce guanosine , -cyclic monophosphate (cgmp) which mediates most of the physiologi- cal effects of no on smooth muscle including vasodilation and broncho- dilation. no reaction products may also mediate other physiological and pathological functions in the lungs and many other organ systems. due to the high reactivity, no participates in a wide variety of reactions at different sites within the cell, lung tissue, extra- cellular fluids, and intravascular com- partments. primary reactions that may involve no intracellularly and extracel- lularly include its reaction with oxygen, superoxide, haemoglobin, another molecule of no, enzymes containing iron-sulfur centres, heme-containing proteins, and thiol proteins. notably, no undergoes a direct bimolecular reaction with superoxide (o ) yielding peroxynitrite (onoo ) at a rate that is even faster than the dismutation of o by superoxide dismutases (sod), which puts no at the epicentre of oxidative metabolism and inflammation. regulation of no synthesis by oxygen all nos isoforms require the presence of oxygen for activity. although it is recognised that oxygen is a substrate for nos, its effects on the regulation of nos activity are more complex than a simple enzyme-substrate interaction. interestingly, the effect of hypoxia on no levels in the airway is primarily a result of airway and alveolar oxygen tension rather than vascular oxygen tension. one proposed mechan- ism(s) for oxygen regulation of nos activity is outlined in fig . nos activity during the steady state includes an active cycle (a) that generates no and an inactive cycle (b) that involves formation and decay of a heme-no complex. in the active cycle, oxygen binding to ferrous heme (fe +) is limit- ing for enzyme activity. in contrast, resolution of the inactive cycle and entry into the active cycle is oxygen-depen- dent due to effects on the stability of the heme-no complex. this includes a reaction between the heme-no complex and oxygen which results in loss of the heme-no complex (fig ). the oxygen concentration in intact tissues ranges from to mm, with the highest levels found in the lung. airway epithelial cells are unique in their exposure to oxygen since, above a thin layer of epithelial lining fluid, the airway cells are exposed directly to air containing % oxygen. based on oxy- gen solubility and the low differential oxygen gradient between overlying fluid to intracellular endoplasmic reticulum ( – mm), the levels of oxygen in airway epithelial cells may actually approach mm. thus, the michaelis constant (kmo ) determined for nos ii ( mm), but not nos iii ( mm) or nos i ( mm), is well within the physiological range of oxygen concen- trations in lung epithelial cells. impor- tantly, kmo for no synthesis in the intact human lung ( mm) is similar to nos ii kmo in vitro. regulation of nos gene expression by oxygen the immediate effects of short term changes in oxygen concentration on the table nitric oxide synthase enzymes nos isoforms numerical designation other designation expression regulation no output chromosome type i nnos constitutive calcium/cam low (picomol) type ii inos inducible induced by cytokines, endotoxin, and oxidants high (nanomol) type iii enos constitutive calcium/cam low (picomol) no, nitric oxide; nos, nitric oxide synthase; nnos, neural nitric oxide synthase; inos, inducible nitric oxide synthase; enos, endothelial nitric oxide synthase; cam, calmodulin. abbreviations: ards, acute respiratory distress syndrome; fad, flavin adenine dinucleotide; fmn, flavin mononucleotide; kmo , michaelis constant; nadph, reduced nicotinamide-adenine dinucleotide phosphate; no, nitric oxide; nos, nitric oxide synthase; o , superoxide; onoo , peroxynitrite; ros, reactive oxygen species; sod, superoxide dismutases editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ activity of nos enzymes are probably due to the effects of oxygen on nos enzyme kinetics. however, prolonged hypoxia can have significant effects on the gene expression of the different nos isoforms. – these transcriptional effects may vary among species or among organ systems in the same species. for example, while hypoxia produces a progressive decline in con- stitutive nos mrna levels in bovine pulmonary artery endothelial cells, – chronic hypoxia upregulates constitu- tive nos expression in rabbit heart and rat lung pulmonary arteries. chronic hypoxia also increases nos expression and nos activity in rat carotid bodies. in this issue of thorax, muzaffar et al describe the effect of hypoxia on the expression of endothelial nitric oxide synthase (nos iii) and gp phox (the active catalytic subunit of nadph oxi- dase), and the formation of superoxide in pig pulmonary artery segments, pulmonary artery smooth muscle cells, and pulmonary artery endothelial cells. they incubated pulmonary artery seg- ments (with and without intact endothelium) and cells (endothelial and smooth muscle cells) in the absence of ambient oxygen for hours and measured the formation of superoxide by ferricytochrome c reduction. they also measured the expression of pro- teins by western blotting and immuno- cytochemistry. the absence of oxygen in the ambient air promoted the forma- tion of superoxide in the studied tissues and cells. various enzyme inhi- bitors were used to determine the source of superoxide production. they also pre-incubated the cells with several inflammatory mediators to determine if they could enhance the effects of hypoxia. a summary of the findings is that hypoxia upregulates nadph oxi- dase and nos iii resulting in increased production of superoxide, no, and peroxynitrite in their system. a major component missing in the model studied by muzaffar and collea- gues is the role of nos ii. in humans nos ii is continuously expressed in the airway epithelium, is a major source of no in the lung, and appears to be the most responsive to hypoxia in the physiological range. due to the free diffusion of no and the close apposition of airways to pulmonary vessels, endo- genous no production in the airways can have significant effects on the pulmonary vessels. the authors com- ment on both enos (nos iii) and inos (nos ii) throughout the paper, but their system does not seem to be appropriate for the study of nos ii which is mainly expressed in the airway epithelium (which the authors did not study) and not in the endothelium or smooth muscle (reported here). the cells they studied do not express nos ii in detectable levels at baseline and that does not change with hypoxia. so, the additional use of nos ii inhibi- tors does not add much. while the authors emphasise the relevance of their findings to acute respiratory distress syndrome (ards), the link is rather speculative. they studied healthy piglets and evaluated their pulmonary artery rings or cells in isolation from the rest of the lung. although they used pre- incubation with some inflammatory markers as a suggestion as to what happens in ards, it would have been more appropriate to study rings from piglets with and without ards. the weak link to ards, however, does not diminish the relevance of the findings. no-superoxide interaction free radicals/reactive oxygen species (ros) may be toxic in two ways. they can interact with metal or organic redox centres and promote irreversible oxida- tion reactions inactivating the target metabolic process, or they can initiate reactions which then become self-sus- taining through the generation of pro- pagating radicals. in either case, this can �� figure simplified proposed mechanism of oxygen regulation of nos enzyme kinetics. nos activity during the steady state includes an active cycle (a) that generates no and an inactive cycle (b) that involves formation and decay of a heme-no complex. in the active cycle, oxygen binding to ferrous heme (fe +) is limiting for enzyme activity. in contrast, resolution of the inactive cycle and entry into the active cycle is oxygen-dependent due to effects on the heme-no complex stability. this includes a reaction between the heme-no complex and oxygen, which results in loss of the heme-no complex. tyr-no onooco - onoo - onooh co h + h + no - nos o - nadph oxidase no hypoxia + + mitochondria xanthine oxidase . figure simplified proposed model of no reaction with superoxide (o ). no undergoes a direct bimolecular reaction with o yielding peroxynitrite (onoo ) at almost diffusion limited rates (k = . – /m/s ). the rate constant is over . times faster than the dismutation of o by superoxide dismutases. by rapidly consuming superoxide, no produces onoo / onooh, a far less reactive oxidant than superoxide that can be further metabolised to innocuous products like no . tyr-no , nitrotyrosine. editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ result in deleterious effects on the cell. the most effective protection against oxidant mediated tissue damage is to scavenge the initiating radical. although no is itself a radical, many of the same chemical and physical properties of no that allow it to exert oxidant effects can also result in anti- oxidant actions. the role of no as an oxidant or an antioxidant probably depends on the local tissue milieu. in an environment where the oxidant load is low, the highly reactive properties of no give the molecule oxidant proper- ties. however, in situations where the oxidant load is high (as in asthma and ards), no plays an antioxidant role by scavenging superoxide and other ros. no undergoes a direct bimolecular reaction with o yielding onoo at almost diffusion limited rates (rate constant (k) = . – /m/s). the rate constant is over . times faster than the dismutation of o ? by sod. by rapidly consuming superoxide, no produces onoo /onooh, a far less reactive oxidant than superoxide that can be further metabolised to innocuous products like no (fig ). muzaffar and colleagues speculate that the upregulation of two enzymes with opposite effects may represent a protective mechanism to counteract the effect of hypoxia or a pathological mechanism leading to the progression of ards. there are no data in their study to favour one explanation over the other. however, based on models in other diseases and on our knowledge of the biology of no and reactions in the lung, one would suspect that, if hypoxia upregulated nadph oxidase without simultaneously upregulating nos expression, the increased release of superoxide (o ) would go unchecked resulting in serious tissue injury. by reacting with superoxide to form perox- ynitrite (onoo ), no produced by nos serves as a scavenger of superoxide resulting in a net antioxidant effect (fig ). the simultaneous upregulation of nos is therefore probably a protective feature. although the link to ards remains speculative, these findings have potential implications for a wide variety of lung diseases from asthma to pul- monary hypertension in which oxidative stress and/or hypoxia have a role. thorax ; : – . doi: . /thx. . correspondence to: dr r a dweik, department of pulmonary, allergy, and critical care medicine, the cleveland clinic foundation, euclid avenue/a , cleveland, ohio , usa; dweikr@ccf.org dr dweik is supported by the national institutes of health grant nih-hl . references dweik ra, laskowski d, ozkan m, et al. high levels of exhaled nitric oxide (no) and no synthase iii expression in lesional smooth muscle in lymphangioleiomyomatosis. am j respir cell mol biol ; : – . dweik ra, erzurum sc. effects of nitric oxide and cyclic gmp on smooth muscle cell proliferation. in: moss j, ed. lam and other diseases characterized by smooth muscle cell proliferation (lung biology in health and disease). new york: marcel dekker, : – . dweik ra, erzurum sc. regulation of nitric oxide (no) synthases and gas phase no by oxygen. in: marczin n, kharitonov sa, yacoub mh, barnes pj, eds. disease markers in exhaled breath (lung biology in health and disease). new york: marcel dekker, : – . dweik ra, laskowski d, abu-soud hm, et al. nitric oxide synthesis in the lung. regulation by oxygen through a kinetic mechanism. j clin invest ; : – . dweik ra, guo fh, uetani k, et al. nitric oxide synthase in the human airway epithelium. zhongguo yao li xue bao ; : – . nathan c, xie qw. nitric oxide synthases: roles, tolls, and controls. cell ; : – . kobzik l, bredt ds, lowenstein cj, et al. nitric oxide synthase in human and rat lung: immunocytochemical and histochemical localization. am j respir cell mol biol ; : – . guo fh, uetani k, haque sj, et al. interferon gamma and interleukin stimulate prolonged expression of inducible nitric oxide synthase in human airway epithelium through synthesis of soluble mediators. j clin invest ; : – . stuehr dj. mammalian nitric oxide synthases. biochim biophys acta ; : – . dweik ra. the promise and reality of nitric oxide in the diagnosis and treatment of lung disease. cleve clin j med ; : , , , . dweik ra. pulmonary hypertension and the search for the selective pulmonary vasodilator. lancet ; : – . dweik ra, comhair sa, gaston b, et al. no chemical events in the human airway during the immediate and late antigen-induced asthmatic response. proc natl acad sci usa ; : – . khatri sb, hammel j, kavuru ms, et al. temporal association of nitric oxide levels and airflow in asthma after whole lung allergen challenge. j appl physiol ; : – . schmidt hh, walter u. no at work. cell ; : – . ozkan m, dweik ra. nitric oxide and airway reactivity. clin pulmon med ; : – . guo fh, de raeve hr, rice tw, et al. continuous nitric oxide synthesis by inducible nitric oxide synthase in normal human airway epithelium in vivo. proc natl acad sci usa ; : – . abu-soud hm, rousseau dl, stuehr dj. nitric oxide binding to the heme of neuronal nitric- oxide synthase links its activity to changes in oxygen tension. j biol chem ; : – . ide h, nakano h, ogasa t, et al. regulation of pulmonary circulation by alveolar oxygen tension via airway nitric oxide. j appl physiol ; : – . grimminger f, spriestersbach r, weissmann n, et al. nitric oxide generation and hypoxic vasoconstriction in buffer-perfused rabbit lungs. j appl physiol ; : – . vanderkooi jm, erecinska m, silver ia. oxygen in mammalian tissue: methods of measurement and affinities of various reactions. am j physiol ; :c – . dweik ra. nitric oxide production in the lung and its regulation by oxygen. in: marczin n, yacoub mh, eds. disease markers in exhaled breath: basic mechanisms and clinical applications (nato science series). amsterdam, netherlands: ios press, : – . liao jk, zulueta jj, yu fs, et al. regulation of bovine endothelial constitutive nitric oxide synthase by oxygen. j clin invest ; : – . melillo g, musso t, sica a, et al. a hypoxia- responsive element mediates a novel pathway of activation of the inducible nitric oxide synthase promoter. j exp med ; : – . phelan mw, faller dv. hypoxia decreases constitutive nitric oxide synthase transcript and protein in cultured endothelial cells. j cell physiol ; : – . baker je, holman p, kalyanaraman b, et al. adaptation of hearts to chronic hypoxia increases tolerance to subsequent ischemia by increased nitric oxide production. adv exp med biol ; : – . sato k, rodman dm, mcmurtry if. hypoxia inhibits increased etb receptor-mediated no synthesis in hypertensive rat lungs. am j physiol ; :l – . di giulio c, di muzio m, sabatino g, et al. effect of chronic hyperoxia on young and old rat carotid body ultrastructure. exp gerontol ; : – . muzaffar s, shukla n, angelini gd, et al. acute hypoxia simultaneously induces the expression of gp phox and endothelial nitric oxide synthase in the porcine pulmonary artery. thorax ; : – . freeman ba, white cr, gutierrez h, et al. oxygen radical-nitric oxide reactions in vascular diseases. adv pharmacol ; : – . dweik ra. nitric oxide reactions in the asthmatic airway. in: marczin n, yacoub mh, eds. disease markers in exhaled breath: basic mechanisms and clinical applications (nato science series). amsterdam, netherlands: ios press, : – . ghamra zw, dweik ra. primary pulmonary hypertension: an overview of epidemiology and pathogenesis. cleve clin j med ; (suppl ):s – . kaneko ft, arroliga ac, dweik ra, et al. biochemical reaction products of nitric oxide as quantitative markers of primary pulmonary hypertension. am j respir crit care med ; : – . editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ early diagnosis of lung cancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . symptoms and the early diagnosis of lung cancer s s birring, m d peake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . significant delays remain in the diagnosis of lung cancer l ung cancer is the leading cause of cancer death in the western world, resulting in nearly deaths in england and wales in . advances in the management of breast, cervical, and prostate cancer have led to improved survival rates, whereas mor- tality from lung cancer has remained largely unchanged. even the best reported year survival rates for lung cancer are only – % and, in england, in patients diagnosed between and the survival rate was only . % at years and % at year. this high mortality is very largely a consequence of patients presenting late when the cancer is already locally advanced or has disseminated. around % of patients with lung cancer have stage iii or iv disease at presentation, therefore excluding them from poten- tially curative surgical resection. detection of the tumour at an earlier stage leads to an improved prognosis, patients presenting with stage ia non- small cell lung cancer and undergoing surgical resection having a year survi- val of around %. patients can (and usually do) live with lung cancer for many years before it becomes apparent. early lung cancer is largely asymptomatic and internalisa- tion of tumours means patients are not alerted by obvious physical changes. it takes around years for a squamous cell carcinoma, for example, to reach a size of mm when it is most commonly diagnosed so, by the time symptoms arise, the risk of metastasis is consider- able. once symptoms appear they are often ignored by patients, delaying the diagnosis and treatment even further. the reasons for patient delay in diag- nosis are poorly understood. lung cancer can present with a wide range of symptoms, the most common being cough, haemoptysis, chest and shoulder pain, dyspnoea, hoarseness, weight loss, anorexia, fever, weakness, and bone pain. guidelines based on this pattern of symptoms have been developed and stress that the physician needs to be alert to the possibility of lung cancer in patients with such symptoms, particularly if they are persistent and occur in those at higher risk of lung cancer—for example, smo- kers and ex-smokers, especially those over the age of and with chronic airflow obstruction. unfortunately, symptoms of lung cancer are largely non-specific and recognition of new symptoms is more difficult in the pre- sence of co-existing respiratory disease such as chronic obstructive pulmonary disease. in addition, the evidence base for these guidelines (and the forthcom- ing updated nice version) is weak and contains no data on the predictive value of symptoms or symptom complexes for the presence or absence of lung cancer in a primary care based population. in this issue of thorax corner and colleagues present the findings of an exploratory retrospective interview study commissioned by the depart- ment of health’s policy research pro- gramme investigating patient delays in cancer diagnosis. detailed interviews were carried out in patients after diagnosis but before treatment to obtain a pre-diagnosis symptom history. this history was compared with primary care and hospital records. cough and dys- pnoea were found to be the most common symptoms among a wide range reported. all patients experienced at least one new symptom before diagno- sis. although the symptoms were reported as a persistent change in health status, they were not interpreted as being serious at their onset. the median interval from the initial change in health status and the symptom prompt- ing the first visit to the general practi- tioner was found to be months, with a further average delay of months to diagnosis. interestingly, there were no significant differences in delays to diag- nosis according to operability of the tumour. the findings of the study by corner et al, although preliminary, are of interest and confirm that there are significant patient related delays for the diagnosis of lung cancer, longer than those pre- viously reported. jensen et al reviewed the time elapsed from symptoms to medical attention reported in studies and found a wide variation from days to months. this wide range of patient delay times is likely to be a result of many factors, including socioeconomic, cultural and health care differences. the reasons why patients did not interpret their symptoms as serious or seek medical attention sooner are not reported by corner et al and need further investigation. the most plausible expla- nation for this is that, while reported symptoms were new, they were too non- specific—especially in the context of co- existing respiratory disease—to raise alarm. a limitation of the data reported by corner et al is that there is no objective validation of the presence and timing of symptoms reported before the first consultation with the gp. patients, with hindsight of the diagnosis, may look for explanations and re-examine past events which we recognise in other clinical situations are often false. prospective studies of the specificity and predictive value of reported symp- toms for the diagnosis of lung cancer and their prevalence in high risk indivi- duals would be required to answer these questions, although such studies are complex, expensive, and long term. other factors that may contribute to patient delays in diagnosis include denial, fear, guilt, other psychosocial issues, poor public health education, and issues relating to access to health care. the fact that the patients in this study did not interpret the early changes as potentially serious may also mean that they were reluctant to bother their gps with what they considered ‘‘trivial’’ complaints. bowen et al studied factors influencing patient delays and found that male patients had longer delays, over half of all patients needed encour- agement from family or friends to see their gp, and % were not aware of the significance of their symptoms and had not received any advice about them. future studies also need to explore how patients respond to changes in health status, why patients with lung cancer appear to have such relatively little contact with their gp, and whether improved public awareness of lung cancer symptoms and easier access to a wider variety of sources of healthcare advice could contribute to achieving earlier diagnosis with a consequent improvement in survival. attempts should be made to develop public health education programmes promoting awareness of lung cancer, a process which needs to be accompanied by the presentation of a more positive image of lung cancer, stressing the fact that early diagnosis saves lives rather than perpetuating the negative image that the current prognosis for the majority of patients is so poor. editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ early symptom recognition in lung cancer will only be worthwhile if it improves outcomes for patients, espe- cially survival. christensen et al found that, for patients with operable lung cancer (stage i/ii), the interval between the trigger symptom initiating contact with the healthcare system and the time of operation was significantly shorter than the time between the trigger symptom and the decision not to oper- ate for patients with stage iii/iv disease. in contrast, mydral et al found the time from onset of symptoms to treatment was shorter in patients with stage iv lung cancer (median . months) than in those with stage i/ii disease (median . months). this is likely to result from the fact that patients with advanced disease had more severe symptoms and signs and received more rapid treat- ment. the current study by corner et al did not find differences in patient delay times according to the stage of lung cancer, but the numbers studied were insufficient to answer this question. studies investigating the effect of hos- pital delays in diagnosis and treatment on prognosis similarly report conflicting results. comparison of the data in these studies is, however, made difficult by the differing definitions of patient delays and clinical differences of patient groups studied. – because of the non-specific nature of the symptoms in question and the fact that a paradigm shift in the behaviour of the population at most risk of develop- ing lung cancer is highly unlikely, attempts at making major progress on early referral at a population level based on symptoms alone seem very unlikely to be successful. other methods of early detection therefore need to be energeti- cally explored to lower the stage at presentation in lung cancer. screening is an attractive option because there is a relatively well defined high risk popula- tion and the potential for curative surgery in early disease. radiological screening has been the most studied. the screening trials of the / s with chest radiography were deemed nega- tive, but the advent of faster spiral and multiple slice ct scanners have led to a renewed interest. preliminary studies of low dose ct screening show promise and formal trials are underway. the demonstration of benefits of screening programmes on the overall survival statistics of the studied population is essential before widespread use of this method is adopted. currently, the improved survival benefits of screening are not known and interpretation of published studies is made difficult since no randomised trial has yet been reported and issues such as lead time and over-diagnosis bias add to the complexity of interpretation. the nat- ural history of malignant nodules as small as mm detected on ct scans is not well described and even nodules only mm in size containing cells represent a fairly late stage in the disease process, considering that at death lung cancer tumours typically have cells. the survival benefit of any screening programme must also outweigh the risks related to managing false positive nodules. the optimum strategy for the management of small lesions identified on screening has not been determined. another potential screening tool is advanced sputum cytology, enhanced by molecular genetics, immunohistochem- istry, including the monoclonal anti- body staining of antigens expressed by lung cancer cells. autofluorescence bronchoscopy may complement cytology with the potential for the detection of metaplasia and carcinoma in situ in bronchial mucosa. a multimodality approach may be required to optimise early detection and management of lung cancer from screening programmes and early attempts at this approach look promising. while efforts consequent upon the national cancer plan and the cancer services collaborative have helped to reduce hospital delays, the study by corner et al reminds us that significant delays remain in the diagnosis of lung cancer before the patient ever gets into secondary care. while this is clearly an important area for future research, it is probable that—in the absence of a major advance in treatment or a sig- nificant further reduction of cigarette consumption—some form of screening is the intervention most likely to have a major impact on the current poor survival statistics, and it is vital that the major funders of national research programmes grasp this difficult nettle as soon as possible. thorax ; : – . doi: . /thx. . authors’ affiliations . . . . . . . . . . . . . . . . . . . . . . s s birring, m d peake, thoracic oncology unit, department of respiratory medicine, glenfield hospital, leicester, uk correspondence to: dr m d peake, thoracic oncology unit and institute for lung health, department of respiratory medicine, glenfield hospital, leicester le qp, uk; mick.peake@ uhl-tr.nhs.uk references office for national statistics. mortality statistics cause. review of the registrar general on deaths by cause, sex and age, in england and wales, , series dh . london: office for national statistics, : . fry wa, phillips jl, menck hr. ten year survey of lung cancer treatment and survival in hospitals in the united states: a national cancer database report. cancer ; : – . seer. www.seer.gov. janssen-heijnen mlg, gatta g, forman d, et al. variation in survival of patients with lung cancer in europe, – . eur j cancer ; : – . office for national statistics. england: cancer survival, – . london: office for national statistics, . pearson fg. current status of surgical resection for lung cancer. chest ; : s. mountain cf. revisions in the international system for staging lung cancer. chest ; : – . geddes dm. the natural history of lung cancer: a review based on tumour growth. br j dis chest ; : – . weiss st. passive smoking and lung cancer. what is the risk? am rev respir dis ; : – . hyde l, hyde cl. clinical manifestations of lung cancer. chest ; : – . department of health. referral guidelines for suspected cancer. london: department of health, . corner j, hopkinson j, fitzsimmons d, et al. is late diagnosis of lung cancer inevitable? interview study of patients’ recollections of symptoms before diagnosis. thorax ; : – . jensen ar, mainz j, overgaard j. impact of delay on diagnosis and treatment of primary lung cancer. acta oncol ; : – . bowen ef, rayner cf. patient and gp led delays in the recognition of symptoms suggestive of lung cancer. lung cancer ; : – . christensen ed, harvald t, jendresen m, et al. the impact of delayed diagnosis of lung cancer on the stage at the time of operation. eur j cardiothorac surg ; : – . myrdal g, lambe m, hillerdal g, et al. effect of delays on prognosis in patients with non-small cell lung cancer. thorax ; : – . o’rourke n, edwards r. lung cancer treatment waiting times and tumour growth. clin oncol ; : – . aragoneses fg, moreno n, leon p, et al. influence of delays on survival in the surgical treatment of bronchogenic carcinoma. lung cancer ; : – . billing js, wells fc. delays in the diagnosis and surgical treatment of lung cancer. thorax ; : – . flehinger bj, melamed mr, zaman mb, et al. early lung cancer detection: results of the initial (prevalence) radiologic and cytologic screening in the memorial sloan-kettering study. am rev respir dis ; : – . henschke ci, mccauley di, yankelevitz df, et al. early lung cancer action project: overall design and findings from baseline screening. lancet ; : – . mulshine jl, smith ra. lung cancer. : screening and early diagnosis of lung cancer, thorax ; : – . mao l, hurban rh, boyle jo, et al. detection of oncogene mutations in sputum precedes diagnosis of lung cancer. cancer res ; : – . tockman ms, gupta pk, myers jd, et al. sensitive and specific monoclonal antibody recognition of human lung cancer antigen on preserved sputum cells: a new approach to early lung cancer detection. j clin oncol ; : – . lam s, macaulay c, leriche jc, et al. detection and localization of early lung cancer by fluorescence bronchoscopy. cancer ; (suppl): – . loewen g, reid m, tan df, et al. bimodality lung cancer screening in high-risk patients. chest ; : – s. department of health. the nhs national cancer plan. london: department of health, . editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ lung function estimates in ipf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lung function estimates in idiopathic pulmonary fibrosis: the potential for a simple classification j j egan, f j martinez, a u wells, t williams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . application of a classification based on simple lung function testing in ipf f or many years the idiopathic pul- monary fibrosis (ipf) community has debated the merits of the histopathological classification of idio- pathic interstitial pneumonia (iip). the ats/ers consensus statement identifies the importance of histological categories of usual interstitial pneumonia (uip) and non-specific interstitial pneumonia (nsip). furthermore, it emphasises that ipf is the clinical correlate of uip. despite the recognition of the impor- tance of histological characterisation, surgical biopsy rates vary considerably. most clinicians do not subject their patients to surgical biopsy, despite the potential prognostic benefit of detailed histological evaluation, because many patients are elderly and have signifi- cantly impaired lung function and other medical co-morbidities resulting in a potentially high mortality rate. in addi- tion, hrct scanning provides diagnostic data of high sensitivity and specificity for the diagnosis of ipf with acceptable interobserver variability. meanwhile, the chronic obstructive pulmonary disease (copd) and lung transplantation communities have applied simple but pragmatically useful classifications. bronchiolitis obliterans syndrome (bos), for example, has been subject to a clinical grading system reflecting the degree of impairment of lung function following lung transplan- tation. the emergence of a classification based on simple lung function testing occurred because of the difficulties in obtaining adequate tissue for the diag- nosis of obliterative bronchiolitis. this is comparable to the situation in ipf where tissue is also difficult to obtain. the success of the classification of bos is reflected by the publication of an updated version. the global initiative for copd (gold) is another example of a con- sensus classification based on simple lung function testing. gold provides a staging system ranging from an ‘‘at risk’’ category to a severe disease cate- gory. based on simple lung function testing, it is reproducible and has facilitated the identification of patients with copd. furthermore, it has enabled worldwide harmonisation of clinical and experimental research studies in copd. recent publications relating to lung function, focusing specifically on ipf, provide a similar opportunity. the his- tological classification proposed by katzenstein and endorsed by the ats/ ers consensus statement potentially allows for the development of a staging system based on simple and widely available evaluation techniques. the aim of such a classification would not be to supersede the histological classifi- cation but rather to build upon it. the aim of this review is therefore to discuss the potential of a grading system for ipf based solely on simple static lung function studies. for judging dis- ease severity we sought a parameter that identified patients with impaired survi- val, defined as less than years. for judging disease progression we sought lung function changes which identified patients at increased risk of mortality. histological classification and lung function the absence of broad agreement on the interpretation of lung function testing in ipf reflects the variability in pub- lished data on the subject (table ). impaired survival has been associated with a variety of findings including no relationship with lung function, increased ratio of forced expiratory volume in second to forced vital capacity (fev /fvc ratio), reduced total lung capacity (tlc), and change in fvc/carbon monoxide trans- fer factor (tlco) after year (table ). formerly a critical confounding factor influencing the interpretation of lung function was the failure to distinguish between histological subsets in iip. consequently, early published data on lung function have been limited by the absence of focus on specific histological subgroups. recent publications have therefore focused on lung function data specifically in the context of uip and nsip, allowing a consistent theme to emerge (table ). a pubmed literature search was performed to identify peer reviewed manuscripts relating to lung function testing in ipf published in – . this period was chosen because it reflects the clinical impact of the characterisation of patients based on histological subsets as described by katzenstein et al in . lung function and disease severity a global view of historical lung function data emphasises that a poor outcome is associated with ‘‘low’’ lung function. schwartz et al highlighted the fact that reduced lung function was associated with limited survival. in a study of individuals who had undergone lung biopsy, univariate analysis showed that there was a greater hazard of death with lower % predicted fvc and lower % predicted tlco. however, clinicians require a specific threshold in the context of disease severity. the study by gay et al emerged as a key publica- tion in the context of the methodology used for appraising the influence of lung function. in contrast to historical stu- dies which reported group differences in survival and hazard ratios, they applied for the first time receiver operator characteristic (roc) curve estimates. roc state the probability that a diag- nostic criterion selects a disease subject correctly rather than a non-disease subject. in the context of lung func- tion, roc curves express the ability of a variable to discriminate between death and/or survival. however, despite the application of roc analysis by gay et al, no lung function variable identified risk of death (table ). this is likely to reflect the efforts to study well characterised patients, resulting in a relatively small number of subjects in the study. disease severity: advanced and limited disease acknowledging the need for a specific threshold value for estimating disease severity, recent data suggest that sever- ity of disease can be categorised as advanced or limited disease on the basis of lung function. extending the study by gay et al by using roc analysis, mogulkoc et al focused on lung func- tion in the context of transplant referral. this study targeted a well characterised group of patients with ipf aged – years. a total of variables influ- encing survival were significant on uni- variate regression analysis. a mul- tivariate stepwise regression analysis identified only % predicted tlco and hrct fibrosis as independent predictors of year survival. roc analysis of % editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ predicted tlco gave an area of . (ci . to . ) and hrct fibrosis score gave an area of . (ci . to . ). it was shown that a gas transfer factor of , % of predicted combined with hrct scores had an % sensitivity and specificity for predicting death within years. this allowed the obser- vation of a simple measure of tlco to be associated with a specific limited time frame of survival. identification of a threshold value associated with increased mortality serves as the basis for a distinction between advanced and limited disease (fig ). the concept of advanced ipf was corroborated by the work of latsi et al. in a retrospective study of patients with a histologically confirmed diagnosis, determinants of early mortal- ity at presentation and mortality after months of follow up were studied. in patients dying within years of presen- tation, the median tlco was % of the predicted value. these authors present patients with advanced disease as an ‘‘early mortality’’ group in whom phy- siology was the best determinant of survival. a key observation in this study is that a subgroup of patients with severely reduced tlco, defined as , % of predicted, had a survival time of less than years irrespective of whether they had uip or nsip. those with a tlco of . % of predicted had a % survival at years. this emphasises that, once a certain threshold of phy- siological impairment is reached, mor- tality is increased. as lung function is the primary investigation performed by pulmonolo- gists, patients may therefore be defined as having advanced disease (tlco , % of predicted), allowing the potential identification of patients with poor early survival. although fvc is predictive of survival in univariate modelling, it does not maintain its effect in multivariate analysis. the severity of ipf is there- fore best graded by tlco estimation. for patients with limited disease (tlco . % of predicted), longer survival is more likely. it is in this latter group that serial lung function studies have parti- cular prognostic value. lung function and disease progression roc curve analysis highlights the fact that tlco is superior to fvc for evaluat- ing disease severity. in contrast, a change in fvc may be the most reliable simple lung function variable to high- light disease progression. when apprais- ing lung function studies of disease progression in ipf, three points deserve consideration: the coefficient of varia- tion of the test, the baseline from which the change occurs, and the time scale used to determine change. the intertest variation has been widely studied. a % change in fvc is required accurately to reflect a change in vital capacity. using tlco requires a change of % or more. consequently, the baseline from which change occurs is vital to observe. because many patients with ipf present with a tlco of , % of predicted, a further % fall from baseline is difficult to document. individuals require adequate pulmonary reserve to exhibit a change in that parameter. inadequate reserve may explain why a significant proportion of patients fail to show evidence of lung function progression. patients with lim- ited disease or adequate pulmonary reserve therefore lend themselves to evaluation of disease progression. the time required to observe a change in lung function is also critical. as the mean survival of some groups of patients may be as low as . years, a prolonged period of observation of, for example, year biases a study towards patients with favourable survival and limited disease. hanson et al were the first to study the change in lung func- tion over year. they studied patients and evaluated the influence of a % change in fvc and a % change in tlco. this cohort had favourable characteristics including a mean age of years and a mean survival of months. the mean survival of patients exhibiting a change ( % of the total) in fvc was . years. the mean survival of patients exhibiting a change was also . years in tlco ( % of the total.) acknowledging this, two recent pub- lications progress the strategy described by hanson et al. firstly, collard et al, in a study of patients with uip, evaluated change in lung function over both and months. the median table summary of lung function studies in ipf author subset n age (years) fvc tlco (survival months) result schwartz no % % na decreased tlc/tlco associated with dyspnoea schwartz no % % increased fev /fvc ratio hanson no % % year: % drop fvc, % drop tlco: increased mortality erbes no % % reduced tlc hubbard no % % no lf variable associated with mortality gay yes uip % uip % no lf variable associated with mortality mogulkoc yes uip % uip % tlco % predicted: % sensitivity/ specificity year survival wells yes uip % % mortality associated with reduced tlco, fvc, tlc latsi yes uip % nsip % uip % nsip % uip nsip tlco % predicted: early mortality collard yes uip % uip % reduced survival: % drop in fvc months flaherty yes uip % nsip % uip % nsip % (total group) reduced survival: % drop in fvc/ months subset refers to whether the authors specified the histological subset studied. age and fvc/tlco are median values; survivals are mean values. lf, lung function; fev , forced expiratory volume in second; fvc, forced vital capacity; tlc, total lung capacity; tlco, carbon monoxide transfer factor; uip, usual interstitial pneumonia; nsip; non-specific interstitial pneumonia. �� !��"�� #�� $�� figure a classification of ipf based on simple lung function criteria. tlco, carbon monoxide transfer factor; fvc, forced vital capacity. editorial www.thoraxjnl.com o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://th o ra x.b m j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ survival of the patients subject to month evaluation was . years and . years for those studied at months. the mean tlco of the group was % of predicted. changes in tlc % predicted, fvc % predicted, and tlco % predicted over months predicted sur- vival. of these, the change in fvc % predicted was the best predictor. flaherty et al studied patients, of whom had uip and had nsip. the mean tlco of the group was % of predicted. % of patients had a fall of . % in fvc and % of patients remained within % of baseline. on multivariate analysis, controlling for histological subgroups and baseline lung function, a change in fvc over months was an independent risk factor for mortality. both studies included patients with preserved tlco in the region of % of predicted. changes in tlco are an alternative measure of disease progression. latsi et al observed a higher mortality in patients with a decline in tlco at and months, whether trends were quan- tified numerically or categorically. however, repeat tlco measurements can be difficult to standardise, explain- ing the need for a greater change in tlco than in fvc in order to categorise deterioration. in the study by latsi et al, serial tlco trends had only a minimal prognostic advantage over serial fvc trends and the analysis included a significant subset of patients with advanced disease. in the recently published interferon gamma- b treat- ment study only % of patients with a mean tlco of % were defined as having disease progression based on a % change in tlco (bill bradford, personal communication). therefore the authors favour classifi- cation of disease progression based on change in fvc at months rather than year because this allows the early identification of progressive disease. however, in patients with limited dis- ease the potential value remains of re- evaluating progression at year, as demonstrated by flaherty and latsi. re-evaluation at months may be particularly important in the context of a ‘‘marginal’’ decline in fvc of – %, which may reflect either measurement variation or genuine disease progres- sion. thus, the definition of disease progression using change over months should not obscure the need to refine prognostic evaluation at year and at least monthly intervals thereafter. benefits and disadvantages of a classification the potential benefits of a classifica- tion based on lung function are sub- stantial. there is a critical need for a classification based on lung function for a condition in which it is difficult to acquire tissue. it would standardise nomenclature and facilitate entry into emerging treatment studies. it may also optimise referral for lung transplanta- tion. a limited window of opportunity exists to refer ipf patients for lung transplantation. the short transplant window is reflected by the high mortal- ity rate in patients with ipf awaiting lung transplantation. the proposed classification, particularly based on the concept of advanced disease, may facil- itate more accurate referral, the time of listing being determined by local organ availability. although a tentative and provocative first step, there are potential limitations to the proposed classification. it must be acknowledged that the data presented by mogulkoc and latsi are retrospective and should ideally be validated by a prospective evaluation. furthermore, thabut and fournier emphasise weak- nesses with reference to the definition of disease progression based on a % change in fvc. for instance, a change in fvc from % predicted to % pre- dicted is not clinically comparable to a change from % to %. there is also an inherent difference between group data and the individual patient. although group data show that % of patients who exhibit a % fall may survive years, this does not equate with an individual patient having a % chance of surviving years. it must also be recognised while monitoring disease progression that only a proportion of patients may exhibit a change in lung function. in the study by flaherty et al, % of patients had a fall of . % in fvc while % of patients remained within % of baseline. in the interferon gamma- b treatment study, % of patients were defined as having disease progression based on a change in fvc. to address this, specialist centres have developed composite indices containing a mixture of parameters, with and without imaging data. preliminary analysis suggests that such scoring systems may be more accurate prognos- tically than individual lung function variables. however, these scoring sys- tems may not be easily applicable to the broader community of non-specialist centres, especially when exercise testing and radiographic profusion scores are included. the focus should therefore be firstly to emphasise the need for staging based on lung function tests. although a lung function classification is a first step, in the future hrct data and simple field exercise tests such as the minute walk test may provide com- plementary data. the proposed lung function schema provides a trigger for discussion and a framework from which additional simple and pragmatic mar- kers of progressive disease can be identified. acknowledgements the authors acknowledge the irish lung fibrosis association, the university of michigan fibrotic lung disease network, and the brompton interstitial lung disease group. thorax ; : – . doi: . /thx. . authors’ affiliations . . . . . . . . . . . . . . . . . . . . . . j j egan, the mater misericordiae hospital and st vincent’s university hospital, the conway institute, dublin molecular medicine center, university college dublin, ireland f j martinez, taubman center , e medical center dr, ann arbor, mi - , usa a u wells, interstitial lung disease unit, emmanuel kaye building, manresa road, london sw lr , uk t williams, alfred hospital, monash university, melbourne, australia correspondence to: dr j egan, advanced lung disease and irish national lung transplant program, the mater misericordiae hospital and st vincent’s university hospital, the conway institute, dublin molecular medicine center, university college dublin, ireland; jegan@mater.ie conflict of interest: none references american thoracic society/european respiratory society. international multidisciplinary consensus classification of the 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rubens mb, et al. idiopathic pulmonary fibrosis: a composite physiologic index derived from disease extent observed by computed tomography. a j respir crit care med ; : – . lama vn, flaherty kr, toews gb, et al. prognostic value of desaturation during a -minute walk test idiopathic interstitial pneumonia. am j respir crit care med ; : – . moloney e, clayton n, mukergee s, et al. shutte walk test in idiopathic pulmonary fibrosis. respir med ; : – . online first . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . online first in thorax j a wedzicha, s l johnston, d m mitchell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . w e are pleased to announce that thorax is about to start posting all original articles on its web- site in an online first section 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j.co m / t h o ra x: first p u b lish e d a s . /th x. . o n m a rch . d o w n lo a d e d fro m http://thorax.bmj.com/ can we model the scenic beauty of an alpine landscape sustainability , , - ; doi: . /su sustainability issn - www.mdpi.com/journal/sustainability article can we model the scenic beauty of an alpine landscape? uta schirpke , sonja hölzler , georg leitinger , maria bacher , ulrike tappeiner , and erich tasser ,* institute for alpine environment, eurac research, viale druso , bolzano, italy; e-mails: uta.schirpke@eurac.edu (u.s.); sonja.hoelzler@googlemail.com (s.h.); ulrike.tappeiner@uibk.ac.at (u.t.) institute of ecology, university of innsbruck, sternwartestr. , innsbruck, austria; e-mails: georg.leitinger@uibk.ac.at (g.l.); maria.bacher@uibk.ac.at (m.b.) * author to whom correspondence should be addressed; e-mail: erich.tasser@eurac.edu; tel.: + - - - ; fax: + - - - . received: december ; in revised form february / accepted: february / published: march abstract: during the last decade, agriculture has lost its importance in many european mountain regions and tourism, which benefits from attractive landscapes, has become a major source of income. changes in landscape patterns and elements might affect scenic beauty and therefore the socio-economic welfare of a region. our study aimed at modeling scenic beauty by quantifying the influence of landscape elements and patterns in relationship to distance. focusing on alpine landscapes in south and north tyrol, we used a photographic questionnaire showing different landscape compositions. as mountain landscapes offer long vistas, we related scenic beauty to different distance zones. our results indicate that the near zone contributes by % to the valuation of scenic beauty, the middle zone by %, and the far zone by %. in contrast to artificial elements, naturalness and diversity increased scenic beauty. significant differences between different social groups (origin, age, gender, cultural background) occurred only between the local population and tourists regarding great landscape changes. changes towards more homogenous landscapes were perceived negatively, thus political decision makers should support the conservation of the cultural landscape. keywords: distance zones; landscape composition; landscape diversity; regional development; scenic beauty; socio-demographic groups open access sustainability , . introduction all over the european alps, major land-use changes result in altered landscape patterns [ – ]. whereas productive areas continue to be used, less productive areas have been abandoned, leading to natural reforestation [ – ]. such land-use change produces a change in the appearance of the landscape. the visual character of landscapes affects human well-being in different ways, especially in terms of aesthetic appreciation, human health, and human relations [ – ]. hence, an attractive environment can support a positive future development in europe’s mountain areas, especially, in terms of economic benefits related to tourism, as mountain landscapes are appealing environments [ , – ]. scenic beauty assessments and modeling approaches, which consider recent landscape dynamics, can support the local decision makers and landscape planners towards a sustainable development [ , ]. when assessing scenic beauty, human perceptions and physical properties of landscapes with all visual elements and also their composition have to be taken into account [ – ]. bourassa [ ] relates landscape aesthetics to the cultural, biological and personal dimensions. based on the biological dimension and cultural/social behavior, diverse studies have analyzed landscape appreciation [ , ]. the biological dimension includes evolutionary principles, describing landscape composition and scenic beauty through visual concepts or attributes [ , – ]. with regard to alpine landscapes, several authors discussed attributes like naturalness, wilderness, and diversity and studied the consequences of land-use processes of intensification, abandonment, and reforestation [ , , , ]. tveit et al. [ ] define naturalness as the closeness to a preconceived natural state. this relates to the perceived degree of naturalness, which may differ greatly from the “degree of naturalness” as understood by scientists [ ]. in landscape aesthetics, naturalness is considered as an important positive predictor [ , – ] and great scenic beauty has been associated with natural landscape features like mountains, water, and vegetation [ , – ]. in contrast, anthropogenic influences, for example, urban growth, infrastructures, or garbage, are perceived negatively [ – , – ]. besides specific landscape features, also landscape patterns can be related to scenic beauty and landscape diversity is perceived positively [ , , ]. furthermore, distance, in terms of openness or extent of view, has also been mentioned as a major aspect of scenic beauty in several studies [ , , , ]. however, visual scale concepts, such as landscape rooms, visibility, openness, enclosure, spaciousness [ ] have mostly been tested in flat areas or landscapes with small topographical variation [ ]. in alpine landscapes, places with higher elevation have longer vistas in respect to flat landscapes, but mountains can also limit the view [ , ]. with increasing distance, the long vistas affect visual properties, object appearance, color differences, and lightness contrast [ ]. to account for these visual variations, several studies related scenic beauty assessments to different distance zones and distinguished usually three zones [ – ]. ribe et al. [ ], for example, tested impacts of vistas and harvests on public perception with regard to forest management. germino et al. [ ] examined the total visible proportional area for – km, – km, and – km, mentioning that especially for distant views over more than a few kilometers, the perception of viewsheds is not very well discussed. their results imply that the near zone is particularly important for humans’ perceptions and helps shape the way people assess and understand a landscape. schirpke et al. [ ] adapted the distance zones for the european alps ( – . km, . – km, sustainability , – km) to perform a visibility analysis accounting for scale and color variations with increasing distance. however, none of these studies related humans’ perceptions of landscape changes in relationship to different distance zones. in this study, we therefore focus on the influence of distance on perceived scenic beauty of mountain regions. to support a sustainable development of touristic mountain regions [ , ], it is important to consider landscape perceptions of both the local population and tourists. different studies examined whether landscape perceptions depend on social groups [ , , , ]. bourassa [ ] refers to cultural rules which play an important role for perceived scenic beauty, because humans’ perceptions are related to specific backgrounds creating social groups which are derived from cultural developments. as different social groups have diverse expectations of a landscape [ ], they may evaluate its scenic beauty differently. bauer et al. [ ] showed in their study in switzerland that the german-speaking part had a positive attitude to increasing forest areas while the french-and italian-speaking parts had a negative attitude to the same phenomenon. beza [ ] explained the different perceptions of a mountain landscape between tourists and the local population by specific cultural ideas. in contrast, many studies found substantial agreement across different groups [ , – ] indicating that the variations between observer’s judgments are less than the variations between landscapes [ ]. these studies, however, did not focus on differences between tourists and local residents. the objective of our study was to generate a model for scenic beauty of mountain regions based on depth of view, landscape elements, and perceptions of different social-demographic groups. real [ ] specified that predictors based on the psychophysical paradigm [ ] are suitable for building a general model of scenic beauty. thus, we used a photo-based questionnaire with different alpine landscapes for quantifying the influence of distance as well as the positive and negative effects of landscape elements on scenic beauty to propose a simple approach for modeling scenic beauty. our modeling approach was based on the following hypotheses: ( ) the more view zones are visible in a landscape, the greater is its scenic beauty. ( ) the closer a landscape element is to the observer, the stronger its influence (negative or positive). ( ) perceptions vary between socio-demographic groups. . methods . . study sites the present study was carried out in south tyrol (italy) and north tyrol (austria), both situated in the central alps. the landscape of the study site in south tyrol, the gsies valley, with a size of km², is dominated by coniferous forests ( % of the municipal area), grassland with high land-use intensity ( % of the municipal area), and grassland with low land-use intensity in the subalpine–alpine zones ( % of the municipal area). settlement takes up % of the valley floor. the municipality has experienced a big increase in forest (+ %) within the last years and a decrease in grassland with low land-use intensity (- %). the study site in north tyrol, neustift im stubaital, with a size of km², is characterized by a densely settled valley floor ( % of the municipal area is urbanized). the landscape is composed of rock and scree areas ( . % of the sustainability , municipal area), coniferous forests of the montane and subalpine zone ( %), alpine meadows and dwarf shrub communities ( %), and the stubai glacier ( %). in both study sites, arable farming has almost ceased. . . questionnaire and interviews to analyze the landscape features in relationship to distance and people's differences in the perception of scenic beauty, we used a standardized photograph-based questionnaire containing six photo series; each series was made up of four images: one real photograph and three different versions of the original photograph modified with adobe photoshoptm (figure ). there are different techniques for visualizing landscape scenarios, for example on-site visits, photographs, digital image editing and virtual landscape simulators [ ]. for our study, we used digital image editing to generate natural-looking and photo-realistic images [ , ]. the technique allows changing only one variable in the picture, while the others are controlled or remain constant [ ]. simulated environments can be used to visualize hypothetical conditions [ , ]. to test the hypotheses and , we used the three distance zones according to schirpke et al. [ ]: in the near zone ( – . km), scattered elements (e.g., trees, row of trees, water, houses) and land-use types can be recognized; in the middle zone ( . – km), elements and land-use types make up complexes of shapes and forms (e.g., different types of forest areas, diverse landscapes); in the far zone (> km), only mountain silhouettes with large-scale areas (forest, agricultural area, snowfield or glacier) are clearly identifiable. the different photo series were related to the hypotheses and as described in the following: • hypothesis : to analyze the influence of the depth of view, we created series by removing the landscape features related to the distance zones from the original picture (figure ). series was composed of different pictures with different view extents. series . (depth of view): pic _ : all three distance zones; pic _ : near and middle zone. pic _ : all distance zones but without any elements in the near zone; pic _ : only near zone. series . (depth of view): pic _ : dense forest with no vistas; pic _ : sparse forest with small vistas; pic _ : dense forest with a small clear cutting with vista; pic _ : vista above tree tops. • hypothesis : to verify the influence of specific landscape elements from literature, we used the picture series – (figure ). naturalness (series and ), urban sprawl (series ), and landscape diversity (series ) may have a positive or negative influence on scenic beauty [ , – ]. the picture of series was modified in the middle zone indicating different degrees of human influence. in series , we used a landscape with and without a stream because water, one aspect for a natural environment, is highly preferred [ ]. series represented different degrees of urban sprawl in the near and middle zones. series showed different landscape patterns in the middle zone. series . (naturalness): pic _ : slope with widespread dense forest; pic _ : slope with dense forest and strong human influence; pic _ : slope with sparse forest; pic _ : slope with sparse forest and strong human influence. sustainability , series . (naturalness): pic _ : near-natural stream and riparian vegetation; pic _ : near-natural stream; pic _ : artificial stream course; pic _ : landscape without a stream course. series . (urban sprawl): pic _ : large human settlements and ski tourism ( % of the picture); pic _ : large human settlements ( % of the picture); pic _ : actual situation ( % settlements of the picture); pic _ : only isolated buildings ( % of the picture). series . (landscape diversity in the valley floor): pic _ : diverse land use; pic _ : prevalent grassland landscape with many structural elements; pic _ : prevalent grassland landscape with a few structural elements; pic _ : prevalent grassland landscape without any structural elements. to answer hypothesis , the respondents were selected in public places on the basis of a stratified random sampling, with the aim to get more than persons in each group (origin, gender, age, cultural background) (table ). the response rate was % and the participants, locals and tourists of both study areas, were asked to rank the series – by their scenic beauty without the possibility of equal rankings: from = least beautiful to = most beautiful. the respondents spent in average – minutes to fill out the questionnaire. figure . pictures of landscape scenarios – with information on the manipulated view zones: near zone (n), middle zone (m), and far zone (f). the original pictures are marked with a cross. the pictures of each series were ranked from = least beautiful to = most beautiful. the median is shown under each picture, on the right. the letters (a, b, c, d) describe the significant differences of evaluation of the pictures per series (mann-whitney u test, p < . ). sustainability , figure . cont. table . socio-demographic characteristics of the respondents. origin (n = ) gender (n = ) age (n = ) cultural background- tourists ( n = ) locals tourists female male < – > german italian the rankings of the six different picture series were not comparable with each other because each series was related to a specific theme and the pictures were ranked only within each series. to compare the different themes, a seventh series was added at the end of the questionnaire, composed of the six original photographs from series – . the respondents were also asked to rank series , ranking here ranging from = least beautiful to = most beautiful. . . statistical analyses the statistical analyses were arranged in spss statistics . the median of the ranked scenic beauty (total respondents) was calculated for all pictures. each group (origin, gender, age, cultural background of tourists) was tested. we used the mann-whitney u test (p < . ) to compare the median values of the series. based on series , we derived weighting factors for the distance zones. sustainability , by series , the weighting result was verified. series to were used to identify and quantify the influence of landscape elements by calculating landscape composition factors. based on series , a scenic beauty model was defined by using generalized linear models (glm). . results . . modeling scenic beauty and sensitivity analyses according to our hypotheses, depth of view and the closeness of specific landscape elements are important aspects of scenic beauty. to evaluate the influence of distance, but also the composition of the landscape in the near zone (positively or negatively perceived elements) on the perception process and, thus, on the scenic beauty of landscapes, we developed a general model allowing us to compare landscape properties and to evaluate its scenic beauty. we generated the scenic beauty model in two steps: ( ) distance weighting factors, and ( ) landscape composition factors. . . . distance weighting factor the results of series and supported the hypothesis . the most beautiful landscape was the landscape with all visible distance zones (picture _ ). while dense forest without any vista was rated worst (picture _ ), respondents preferred the vista above tree tops (picture _ ). furthermore, series indicated that the influence of landscape elements on scenic beauty depends on distance. judged as least beautiful by % of the respondents was the landscape without landscape elements in the near zone (picture _ ). even the landscape with only the near zone was rated better (picture _ ). to build the scenic beauty model, in a first step, weighting factors for the distance zones z(n,m,f) were determined based on the series (equation to equation ). the sum of all zones together is z = . the following weighting factors for the distance zones were derived: near zone z(n) = . , middle zone z(m) = . , and far zone z(f) = . . each original value of the survey (series ) was then multiplied with these weighting factors (table ). 𝑍𝑍(𝑛𝑛) = �̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ �̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ ( ) 𝑍𝑍(𝑚𝑚) = ��̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ − �̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ � �̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ ( ) 𝑍𝑍(𝑓𝑓) = ��̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ − �̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ � �̅�𝑟𝑝𝑝𝑝𝑝𝑝𝑝 _ ( ) where by z(n) = near zone weighting factor, z(m) = middle zone weighting factor, and z(f) = far zone weighting factor. �̅�𝑟pic = mean rank of scenic beauty of the pictures – of series (see figure ). . . . landscape composition factors hypothesis was tested by analyzing series to . in the near zone, naturalness and also diversity of elements emerged as very important factors in scenic beauty as shown by the results of series sustainability , (figure ). the most liked landscape was the one with the near-natural stream and the riparian vegetation. the landscape with an artificial stream and the same landscape without a stream received the worst ratings. in the middle zone, a sparse forest with a strong human influence (picture _ ) was even less liked than a dense forest (picture _ ). increasing urban sprawl in the near and middle zones of series was evaluated negatively. series put the focus of attention to landscape diversity in the middle zone. the actual landscape in the study area today, a typical grassland landscape, was liked best. in contrast, the landscape with diverse land use was less preferred. the results suggest that in the near zone naturalness and diversity are important, but that strong urban sprawl can lower the perceived scenic beauty. the results of series to indicate also that the influence of landscape characteristics or single elements changes with distance. to account for the positive or negative influence of landscape elements on scenic beauty in relationship to their distance from the observer, we introduced three different factors. first, the composition weighting (c) for different elements, whether positive (increasing scenic beauty) or negative (decreasing scenic beauty), derived from literature [ – , , ]. all element compositions not clearly attributed as positive or negative were considered neutral and were not weighted. second, we assessed dominances of these positive or negative landscape elements (pc) by calculating their area-weighted distribution on the picture. third, we counted the different landscape area types (not the single elements) such as forests, grasslands, settlements, and arable lands to consider landscape diversity (dc) (table ). finally, the weighted scenic beauty (w) was calculated by applying equation ( ): w = (z+(c*pc))*dc ( ) where z = distance weighting factor, c = positive/negative composition weighting, pc = dominance, dc = diversity. the coefficient of determination (r ) increased when considering the distance weighting factor (z) and stepwise including the landscape composition factors (c, pc, dc) reaching finally a high correlation (r = . ) (figure ). table . median of scenic beauty of series (s ) and weighted scenic beauty (w) for each picture. the weighted scenic beauty (w) was calculated by using the distance weighting factor (z), positive/negative composition weighting (c), dominance (pc), and diversity (dc). picture number distance weighting factor landscape composition factors scenic beauty visible distance zones z c pc dc s w _ z(n) + z(m) + z(f) . urban sprawl = negative (− ) . . _ z(n) + z(f) . neutral ( ) . _ z(n) . neutral ( ) . _ z(n) + z(m) . water = positive (+ ) . . _ z(m) . urban sprawl = negative (− ) . . _ z(n) + z(m) . urban sprawl = negative (− ) . . sustainability , figure . correlation of the medians of scenic beauty of series and weighted scenic beauty (w) using the distance weighting factor (z), positive/negative composition weighting (c), dominance (pc), and diversity (dc). . . viewing human impact hypothesis was not approved completely because there were significant differences in only . % of all ratings in the different groups (cf. table ). in the gender group, only two significant differences could be found for pictures _ and _ . the results of the origin group suggest that landscapes with human influence in the form of artificial elements (picture _ ) are rated better by tourists than by locals. in addition, tourists also rated reforestation better than locals (pictures _ , _ ). analyzing the two cultural background groups of tourists (italian, german), we found that italian tourists rated artificial elements (picture _ ) and reforestation (picture _ ) in the landscape better than german tourists did. the age group returned particularly significant differences between respondents over years and those under years. the older generation rated open, structured landscapes better than younger respondents did (pictures _ , _ , _ ). as hypothesis was not verified, we did not include specific perception of different socio-demographic groups in our modeling approach. sustainability , table . the median of scenic beauty of series – in the groups origin, gender, age and cultural background. group differences were tested with a mann-whitney u test (p < . ). the letters (a, b, c) describe the significant differences between the pictures within a group and are highlighted in grey. origin (n = ) gender (n = ) age (n = ) cultural background-tourists (n = ) picture locals tourists female male < years – years > years german italian _ a b _ _ a b _ _ a b a b a b _ a b _ _ a a b a b _ a b a b _ _ a b a b _ a a b _ _ a b _ a b a b _ a b _ a b a a b a b _ _ a b a a b _ a b _ a a b _ _ a b a b a b c a b _ . discussion . . influence of view zones and distance the results suggest that distance played a major role in the perception of alpine landscapes. topography influences the depth of view which is central to our understanding of landscapes and perceived scenic beauty [ , ]. as confirmed by tveit [ ], the distance from the observer was important for the perception of scenic beauty because people’s ability to distinguish between features is decreasing with distance [ ]. we used the distance zones, adapted to the alps, by schirpke et al. [ ]: the near zone – . km, the middle zone . – km, and the far zone – km. for each distance zone, we derived the distance weighting factors: near zone %, middle zone %, and far zone %. sustainability , landscape attributes and elements like naturalness, diversity and urban sprawl are often used as predictors for scenic beauty, however, mostly not related to view zones [ , , – ]. similar to other studies [ , , – ], attributes like naturalness, presence of water, and diversity of elements emerged as positive predictors for scenic beauty in the near zone. in contrast, the modern human settlement in the near zone and also human influence as ski tourism infrastructure in the middle zone were evaluated negatively. an unexpected result emerged for the landscape diversity of the middle zone (series ). in the literature, diversity is generally considered an attribute for a high scenic beauty of landscapes [ , , ]. accordingly, lindemann-matthies et al. [ ] found a high preference for diverse landscapes with structural elements in the middle zone but a low rating for arable land. in our study, it was not the most diverse landscape that was rated highest but a medium structured grassland [ ]. this result may be explained by the view of the valley seen from above and at a larger distance. furthermore, the results indicate that the younger generation (under years) was not familiar with the pattern of a diverse landscape and that for the middle zone concepts like coherence [ , , ] and legibility [ ] were more important than diversity [ , , ]. . . influence of group differences contrary to the hypothesis , no significant differences emerged for . % of all ratings in the different groups indicating that the landscape variations were much greater than the variations of observer’s judgments as also confirmed by other studies [ , – ]. although . % of all ratings were significantly different, the median values are in most cases the same. our study therefore reflects the perceptions of all respondents without distinguishing between different socio-demographic groups [ ]. nevertheless, some differences have to be pointed out. locals in south and north tyrol evaluated landscape changes more critical than tourists. the local group seemed to be attached to the current landscape or would prefer a development towards traditional cultural landscapes. in contrast, the tourist group seemed to be more open to greater landscape changes like reforestation or human-caused landscape elements. according to our results, the locals are familiar with the cultural landscape through their professional or leisure uses of it [ ]. big changes (e.g., reforestation or urban sprawl) may be interpreted as loss of home land [ ]. unlike younger people, the + generation also preferred traditional cultural landscapes with great landscape diversity. with the decrease of diverse landscapes today, people are not familiar any more with landscape diversity and thus not able to read the landscapes [ ]. the older generation, however, has known these landscapes from childhood. as the perception of scenic beauty starts at an early age, the older generation rated this landscape type better [ ]. tourists rated a landscape characterized by artificial elements and facilities but also natural reforestation higher than locals did. in tourist destinations like south tyrol and tyrol, skiing areas and the related facilities offer many holiday options for tourists. hunziker [ ] stated that an ideal landscape depends not only on its scenic beauty but also on other interests. if a ski lift is relevant for touristic interests, then the tourists will rate such a landscape more positively. moreover, differences between the german- and italian-speaking groups could be found. while the italians were more open to extreme landscape changes, for the germans among the tourist respondents, naturalness was more important. sustainability , . . limitations of the method although the questionnaire consisted of a small number of pictures and general conclusions are limited, our results indicate that the modeling approach is a suitable option for creating a scenic beauty model. to validate the model, the study should be repeated with a higher number of pictures indicating clearly the different distance zones and testing various landscape elements especially in the near zone. furthermore, the ranking of the pictures was problematic for comparing the different series among each other. the pictures should therefore be rated to allow a direct comparison. . conclusions related to the initial three hypotheses, we deduce the following conclusions from our results: ( ). distance zones have an important influence on how humans recognize and understand a landscape. landscape elements in the near zone have the most influence on scenic beauty. in terms of view depth, pictures with all three distance zones are voted best. considering processes like reforestation in alpine landscapes, the effect of long-distance views should be taken into account and the aspects of vistas should be included into regional planning. ( ). naturalness and diversity of structural elements have a positive influence whereas artificial elements are judged negatively, especially if they are in the near zone. political decision makers should keep in mind that landscape changes towards more homogenous landscapes are perceived negatively. future governance structures should therefore support the conservation of the cultural landscape. ( ). particularly locals are closely connected to the cultural landscape and find landscape changes problematic. tourists seem more open to landscapes changes with reforestation or human elements. regional planning should respect the perceptions of the local population to assure the quality of life for the inhabitants and, at the same time, account for perception of scenic beauty of tourists to support an economic growth of the region. in general, the modeling results have some important implications for managing sustainable landscapes. in terms of tourism development, viewpoints and forest clearings along roads or hiking trails should be maintained or created to allow long vistas. this is especially important for the alpine zone, which is highly important for touristic activities and where the abandonment of grasslands mostly takes place. as urban sprawl is perceived negatively, the urbanized area should not be extended, but its density increased. in contrast, natural landscape features should be preserved or restored, for example, river landscapes with natural riparian vegetation. furthermore, landscape diversity in general should to be preserved. acknowledgments this work was funded by the interreg iv—eu project (agri)cultural landscape—strategies for the cultural landscape of the future, project no. , cup: b d . sustainability , conflict of interest the authors declare no conflict of interest. references and notes . antrop, m. landscape change and the urbanization process in europe. landscape urban plan. , , – . . schneeberger, n.; bürgi, m.; hersperger, a.m.; ewald, k.c. driving forces and rates of landscape change as a promising combination for landscape change research—an application on the northern fringe of the swiss alps. land use policy , , – . . tasser, e.; ruffini, f.v.; tappeiner, u. an integrative approach for analysing landscape dynamics in diverse cultivated and natural mountain areas. landscape ecol. , , – . . hunziker, m. the spontaneous 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in the visibility of land cover. landscape urban plan. , , – . . tappeiner, u.; tappeiner, g.; hilbert, a.; mattanovich, e. the eu agricultural policy and the environment-evaluation of the alpine region; blackwell: berlin-wien, germany, . © by the authors; licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution license (http://creativecommons.org/licenses/by/ . /). title pursuit and expression of japanese beauty using technology author(s) tosa, naoko; pang, yunian; yang, qin; nakatsu, ryohei citation arts ( ), ( ) issue date - - url http://hdl.handle.net/ / right © by the authors. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /) type journal article textversion publisher kyoto university arts article pursuit and expression of japanese beauty using technology naoko tosa , yunian pang , qin yang and ryohei nakatsu ,* graduate school of advanced integrated studies in human survivability, kyoto university, kyoto - , japan; tosa.naoko. c@kyoto-u.ac.jp (n.t.); pang.yunian. r@st.kyoto-u.ac.jp (y.p.); yang.qin. e@kyoto-u.ac.jp (q.y.) design school, kyoto university, kyoto - , japan * correspondence: ryohei.nakatsu@design.kyoto-u.ac.jp received: january ; accepted: march ; published: march �� abstract: we have been working on the creation of media art, utilizing technologies. in this paper, we have focused on media art created based on the visualization of fluid behaviors. this area is named “fluid dynamics” and there has been a variety of research in this area. however, most of the visualization results of the fluid dynamics show only stable fluid behaviors and a lack of unstable or, in other words, unpredictable behaviors that would be significant in the creation of art. to create various unstable or unpredictable fluid behaviors, we have developed and introduced several new methods to control fluid behaviors and created two media arts called “sound of ikebana” and “genesis”. interestingly, people find and feel that there is japanese beauty in these media arts, although they are created based on a natural phenomenon. this paper proposes the basic concept of media art based on the visualization of fluid dynamics and describes details of the methods that were developed by us to create unpredictable fluid dynamics-based phenomena. also, we will discuss the relationship between japanese beauty and physical phenomena represented by fluid dynamics. keywords: fluid dynamics; high-speed camera; media art; fluid art; japanese beauty . introduction we have created media art in which new technologies play an essential role. recently, we have been interested in the usage of a high-speed camera, through which we have found hidden beauty in various natural/physical phenomena that could be revealed. in particular, we have been interested in the fluid behaviors and have been trying to create media arts by capturing fluid behaviors using a high-speed camera. based on this methodology, we have been trying to create new types of media art (feng chen and tosa ). this area is considered “fluid mechanics” or “fluid dynamics” and there has been a variety of research in this area (munson et al. ; bernard ). as some fluid motions look beautiful, there is another research area called “visualization of fluid motion” (smits and tee tai ). one such beautiful fluid motion is the well-known “milk crown” (krechetnikov and homsy ). however, most visualization results show only stable fluid behaviors and a lack of unstable or, in other words, unpredictable behaviors that would be significant in the creation of art. therefore, to realize various unstable or unpredictable fluid behaviors to create artworks, it is important to introduce several new methods. in this paper we describe two methods that have been developed and introduced by us to create new media art. in one method, we used viscous fluids such as paints with various colors, to which we applied vibration to produce upward motion and shot their “jumping-up” behaviors. it was revealed that jumping-up paints create beautiful forms that change in a very short time. such forms were shot arts , , ; doi: . /arts www.mdpi.com/journal/arts http://www.mdpi.com/journal/arts http://www.mdpi.com http://www.mdpi.com/ - / / / ?type=check_update&version= http://dx.doi.org/ . /arts http://www.mdpi.com/journal/arts arts , , of by a high-speed camera and then based on the editing of the obtained video, a new type of media art called “sound of ikebana” was created (pang and tosa ; naoko tosa et al. ). we introduced a new method of letting color paints injected into fluid and dry ice bubbles interact to create beautiful forms of color paints, which led to the creation of a media art called “genesis” (naoko tosa et al. ). at the same time, we have received comments on these media arts from many western people including art curators, art critics, etc. interestingly, they feel that there is japanese beauty in these artworks. why do they feel japanese beauty in the visualization of a natural/physical phenomenon? for this, based on our consideration, we have developed a hypothesis that one important factor of japanese beauty is based on the extraction and expression of beauty hidden in natural/physical phenomena. as the relationship between our media arts and japanese beauty is fundamental for the value of such arts, we will discuss what japanese beauty is preceding the description of the media arts we have developed. this paper consists of the following sections. in section , a discussion on japanese beauty is carried out and we make a hypothesis that one important factor of japanese beauty is based on the visualization of hidden beauty in nature. in section , the basic concept of the visualization of fluid dynamics as a method to create artworks is described. in section , the detailed description of one type of media art creation method based on the fluid dynamics is described and the media art called “sound of ikebana” based on this method is described. in section , the details of another type of art creation based on the fluid dynamics and also the created artwork called “genesis” is described. finally, in section , we present the discussion and a conclusion is described. . characteristics of japanese art . . what is japanese beauty? what is the essence of japanese beauty? as indicated by bruno taut and others, the harmony between humans and nature has always been emphasized and expressed in japanese artworks and architecture (taut ; taut ). trying to find out the root of such a basic concept, we reach the chinese philosophers lao-tzu and zhuangzi and their philosophy called “taoism (wong ),” in other words “eastern monism,” which emphasizes the unification of humans and nature. although japanese beauty consists of various factors, based on this, it could be said that one factor of japanese beauty is not beauty created by humans but beauty hidden in nature. also, it could be said that one factor of japanese beauty is what japanese artists have tried to extract from nature based on their sensitivity and have expressed in the form of their artworks. this means that there is a close relationship between japanese beauty and natural or physical phenomena. we noticed this based on our experiences described below. we have focused on the creation of artworks based on the methodology of finding and extracting beauty hidden in natural/physical phenomena by using a high-speed camera. one of the authors, naoko tosa, was named as japan’s cultural envoy by the agency of cultural affairs, the japanese government, in and exhibited her artworks in many cities all over the world. during such exhibitions, she received many responses from many people including art critics and art curators saying that “naoko tosa’s artworks showing beauty hidden in nature express beauty that has not been noticed by western people. her artworks include the essence of japanese sensitivity and consciousness”. it sounds a bit strange that western people feel that there is japanese beauty in artworks created based on natural/physical phenomena. next, we will discuss this issue comparing western and eastern art history. the creation of artworks based on beauty in nature is not an idea specific to japan. this idea has been shared in many countries and cultures. in the west, since the greek era, the idea that art is “imitation of nature” has long been accepted and this idea became the basis of the inventions of various art techniques such as perspective. however, since the late modern era, along with the invention of arts , , of the camera, this idea was gradually replaced by another idea that art is the “expression of humans’ inner life” and this trend continues through art movements such as impressionism, cubism, abstract expressionism, and so on. on the other hand, in the east, these theories have not been the mainstream in the art world and the basic concept of eastern monism that stresses the unification of humans and nature has been dominant. in contrast to western artists, eastern artists have neglected the concept of shadows and perspectives which play important roles in western art. having the idea of the unification of humans and nature deep in their minds and using their sensitivities, eastern artists have created their artworks and also their own art world. in china, for example, monochrome ink paintings of landscapes have been popular. in such landscape paintings, based on the old chinese philosophy of taoism, chinese artists tried to draw ideal landscapes—in other words, arcadia. as japan used to continuously import chinese cultures, japanese art was deeply influenced by chinese art. then gradually merging this with the sensitivity of japanese people, especially influenced by the isolation policy in the edo era, japanese artists began to create their own artworks without shadows, and being planar, exaggerated, etc. as these japanese artworks in the modern art era look very fresh to the west, who has denied the idea of “imitation of nature,” in th century, the movement called japonism occurred. consequently, we can interpret the impressions of western people toward naoko tosa’s artworks, when they say that her artworks express japanese beauty, in the following way. as the concept of art in the west has changed from its original idea of “imitation of nature” to the modern and present one of the “expression of human’s inner life or concept,” naoko tosa’s artworks, that are created based on capturing and extracting beauty in nature and that are a contrast to western art, appealed to their sensitivity and made them feel that her artworks express japanese beauty. based on this experience we can make a hypothesis that “one important factor comprising japanese beauty is based is the extraction and expression of beauty in nature.” for the extraction of such beauty, there could be several ways. one such method is based on the sensitivity or natural gifts of artists. another method is based on the usage of technologies, which have been adopted by us. in the next subsection, we will discuss several examples of japanese artworks and artforms showing that one factor of japanese beauty is based on the extraction of beauty hidden in nature and the creation of artworks containing such beauty. . . examples of japanese beauty in japanese art in natural phenomena, such as water flow or wave forms, japanese artists have found beauty and by expressing such beauty, they have created their artworks. one such artform is the well-known artworks by katsushika hokusai (thompson and wright ). also, the specific expression of water flow, called “korin wave,” designed by ogata korin is very well known (fujiura ). such artworks are typical expressions of japanese beauty and have been welcomed by western artists, giving them strong impressions. figure shows fugaku sanjurokkei kanagawa oki namiura (the wave off kanagawa, from views of mountain fuji), a print by katsushika hokusai (clark ). interestingly, the dynamic waveform expressed well resembles the wave form shot by a high-speed camera. figure illustrates the fluid form created by injecting air-gun bullets into fluid with color paints. it is interesting to know the resemblance between these two. arts , , of arts , , x for peer review of figure . “fugaku sanjurokkei kanagawa oki namiura (the wave off kanagawa, from views of mountain. fuji” by katsushika. (in public domain) figure . fluid form captured by a high-speed camera. another example is a basic form of japanese “ikebana” (flower arrangement). the basic form of ikebana has been considered an “asymmetric triangle” (figure ). we have succeeded in creating a similar form by letting color paints jump up by applying sound vibration and by shooting the jumped-up color paints by a high-speed camera, which is described later (figure ). what produces this resemblance between the artworks and the form expressing japanese beauty and natural/physical phenomena? perhaps it is that great japanese artists, such as katsushika hokusai, can find beauty hidden in natural/physical phenomena using their sensitivity and talent and can create artworks using the beauty found. for now, this remains a hypothesis, but we want to reveal this by continuing the creation of artworks based on beauty hidden in nature. figure . “fugaku sanjurokkei kanagawa oki namiura (the wave off kanagawa, from views of mountain. fuji” by katsushika. (in public domain) arts , , x for peer review of figure . “fugaku sanjurokkei kanagawa oki namiura (the wave off kanagawa, from views of mountain. fuji” by katsushika. (in public domain) figure . fluid form captured by a high-speed camera. another example is a basic form of japanese “ikebana” (flower arrangement). the basic form of ikebana has been considered an “asymmetric triangle” (figure ). we have succeeded in creating a similar form by letting color paints jump up by applying sound vibration and by shooting the jumped-up color paints by a high-speed camera, which is described later (figure ). what produces this resemblance between the artworks and the form expressing japanese beauty and natural/physical phenomena? perhaps it is that great japanese artists, such as katsushika hokusai, can find beauty hidden in natural/physical phenomena using their sensitivity and talent and can create artworks using the beauty found. for now, this remains a hypothesis, but we want to reveal this by continuing the creation of artworks based on beauty hidden in nature. figure . fluid form captured by a high-speed camera. another example is a basic form of japanese “ikebana” (flower arrangement). the basic form of ikebana has been considered an “asymmetric triangle” (figure ). we have succeeded in creating a similar form by letting color paints jump up by applying sound vibration and by shooting the jumped-up color paints by a high-speed camera, which is described later (figure ). what produces this resemblance between the artworks and the form expressing japanese beauty and natural/physical phenomena? perhaps it is that great japanese artists, such as katsushika hokusai, can find beauty hidden in natural/physical phenomena using their sensitivity and talent and can create artworks using the beauty found. for now, this remains a hypothesis, but we want to reveal this by continuing the creation of artworks based on beauty hidden in nature. arts , , of arts , , x for peer review of figure . “basic form” of ikebana. (in public domain). figure . fluid form created by sound vibration and captured by a high-speed camera. . visualization of fluid dynamics as a method to create media art study of the behaviors of fluid has been a long-time research topic in physics and this area is called “fluid dynamics” (munson et al. ; bernard ). in physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow. it has several sub-disciplines itself, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). fluid dynamics has a wide range of applications including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting figure . “basic form” of ikebana. (in public domain). arts , , x for peer review of figure . “basic form” of ikebana. (in public domain). figure . fluid form created by sound vibration and captured by a high-speed camera. . visualization of fluid dynamics as a method to create media art study of the behaviors of fluid has been a long-time research topic in physics and this area is called “fluid dynamics” (munson et al. ; bernard ). in physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow. it has several sub-disciplines itself, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). fluid dynamics has a wide range of applications including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting figure . fluid form created by sound vibration and captured by a high-speed camera. . visualization of fluid dynamics as a method to create media art study of the behaviors of fluid has been a long-time research topic in physics and this area is called “fluid dynamics” (munson et al. ; bernard ). in physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow. it has several sub-disciplines itself, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). fluid dynamics has a wide range of applications including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modeling fission weapon detonation. arts , , of determining how to explicitly show the behavior of fluid is another research area called “visualization of scientific phenomena” (smits and tee tai ). based on this visualization process, it became possible for people to watch the actual process of fluid behavior and it has been recognized that various beautiful fluid motions can be created depending on various conditions. as beauty is the fundamental element of art, utilizing fluid dynamics as a method to create artworks has been one of the key concepts of art creation. there are various artworks that utilize the concept of fluid dynamics. these approaches can be classified into two ways. one approach is from a purely scientific side. fluid motions, especially when there are obstacles in the pathway of the fluid, look beautiful and sometimes the visualized result of such fluid motion is considered art. figure shows the result of the visualization of stable flow called “laminar flow”. as the ratio between inertia and viscosity, called “reynolds number,” increases, the laminar flow changes into unstable flow called “turbulence.” in turbulence, frequently various types of vortex occur, some of which look beautiful. figure shows one example of such a vortex. arts , , x for peer review of weather patterns, understanding nebulae in interstellar space and modeling fission weapon detonation. determining how to explicitly show the behavior of fluid is another research area called “visualization of scientific phenomena” (smiths and lim ). based on this visualization process, it became possible for people to watch the actual process of fluid behavior and it has been recognized that various beautiful fluid motions can be created depending on various conditions. as beauty is the fundamental element of art, utilizing fluid dynamics as a method to create artworks has been one of the key concepts of art creation. there are various artworks that utilize the concept of fluid dynamics. these approaches can be classified into two ways. one approach is from a purely scientific side. fluid motions, especially when there are obstacles in the pathway of the fluid, look beautiful and sometimes the visualized result of such fluid motion is considered art. figure shows the result of the visualization of stable flow called “laminar flow.” as the ratio between inertia and viscosity, called “reynolds number,” increases, the laminar flow changes into unstable flow called “turbulence.” in turbulence, frequently various types of vortex occur, some of which look beautiful. figure shows one example of such a vortex. figure . an example of laminar flow. figure . an example of a vortex. although various types of beautiful forms can be created based on such approaches, created forms based on such approaches are not considered pure art. the reason for this is that these phenomena or created forms are still based too much on physics and it is difficult to include an “intention of artists” in the form creation process. there is a clear distinction between physical phenomena and artworks and the border is how much intention of the artists to create artworks is involved in the created work. if there is no intention or the intention is too weak, the created forms are considered physical phenomena rather than artworks. in other words, forms created as physical phenomena are controlled by the laws of physics and there is little space for where something unexpected happens and this unexpectedness is a core part of artworks. on the other hand, there is a different approach which is from an art basis. in this case, fluid usage is strongly controlled by the artists and unexpected phenomena or chance phenomena that happen in the process of fluid usage are utilized by the artists to include something unexpected into figure . an example of laminar flow. arts , , x for peer review of weather patterns, understanding nebulae in interstellar space and modeling fission weapon detonation. determining how to explicitly show the behavior of fluid is another research area called “visualization of scientific phenomena” (smiths and lim ). based on this visualization process, it became possible for people to watch the actual process of fluid behavior and it has been recognized that various beautiful fluid motions can be created depending on various conditions. as beauty is the fundamental element of art, utilizing fluid dynamics as a method to create artworks has been one of the key concepts of art creation. there are various artworks that utilize the concept of fluid dynamics. these approaches can be classified into two ways. one approach is from a purely scientific side. fluid motions, especially when there are obstacles in the pathway of the fluid, look beautiful and sometimes the visualized result of such fluid motion is considered art. figure shows the result of the visualization of stable flow called “laminar flow.” as the ratio between inertia and viscosity, called “reynolds number,” increases, the laminar flow changes into unstable flow called “turbulence.” in turbulence, frequently various types of vortex occur, some of which look beautiful. figure shows one example of such a vortex. figure . an example of laminar flow. figure . an example of a vortex. although various types of beautiful forms can be created based on such approaches, created forms based on such approaches are not considered pure art. the reason for this is that these phenomena or created forms are still based too much on physics and it is difficult to include an “intention of artists” in the form creation process. there is a clear distinction between physical phenomena and artworks and the border is how much intention of the artists to create artworks is involved in the created work. if there is no intention or the intention is too weak, the created forms are considered physical phenomena rather than artworks. in other words, forms created as physical phenomena are controlled by the laws of physics and there is little space for where something unexpected happens and this unexpectedness is a core part of artworks. on the other hand, there is a different approach which is from an art basis. in this case, fluid usage is strongly controlled by the artists and unexpected phenomena or chance phenomena that happen in the process of fluid usage are utilized by the artists to include something unexpected into figure . an example of a vortex. although various types of beautiful forms can be created based on such approaches, created forms based on such approaches are not considered pure art. the reason for this is that these phenomena or created forms are still based too much on physics and it is difficult to include an “intention of artists” in the form creation process. there is a clear distinction between physical phenomena and artworks and the border is how much intention of the artists to create artworks is involved in the created work. if there is no intention or the intention is too weak, the created forms are considered physical phenomena rather than artworks. in other words, forms created as physical phenomena are controlled by the laws of physics and there is little space for where something unexpected happens and this unexpectedness is a core part of artworks. on the other hand, there is a different approach which is from an art basis. in this case, fluid usage is strongly controlled by the artists and unexpected phenomena or chance phenomena that arts , , of happen in the process of fluid usage are utilized by the artists to include something unexpected into their artworks. one representative of such art creation processes is “action painting” (fleck et al. ) led by jackson pollock (landau ). action painting is a form of art creation in which, instead of drawing paintings using a paintbrush, artists throw or draw paints on a canvas. basically, artists have intentions regarding what kind of paints they use and where on the canvas they throw or draw paints. therefore, in addition to the intentions of the artists, a kind of contingency caused by thrown or drawn paints influences the final form of the created artwork. figure shows one of the representative artworks of jackson pollock. although he is now highly evaluated and appreciated in the modern history of art, a problem with his artworks is that it is difficult to find natural beauty, and, therefore, in the beginning, this confused many people. arts , , x for peer review of their artworks. one representative of such art creation processes is “action painting” (fleck et al. ) led by jackson pollock (landau ). action painting is a form of art creation in which, instead of drawing paintings using a paintbrush, artists throw or draw paints on a canvas. basically, artists have intentions regarding what kind of paints they use and where on the canvas they throw or draw paints. therefore, in addition to the intentions of the artists, a kind of contingency caused by thrown or drawn paints influences the final form of the created artwork. figure shows one of the representative artworks of jackson pollock. although he is now highly evaluated and appreciated in the modern history of art, a problem with his artworks is that it is difficult to find natural beauty, and, therefore, in the beginning, this confused many people. based on the problems included in these two approaches, we think that there should be another way of new art creation somewhere in between these two approaches. we started from the former approach but tried to include more unexpectedness in created forms. in sections and , two methods to realize this are described. figure . one of the jackson pollock’s drawings (in public domain). . sound of ikebana: an example of created art as one method to create artworks based on the visualization of fluid dynamics, we have developed a method to combine color ink fluid and sound vibration. . . sound vibration system it is well known that applying vibrations to liquids such as water creates movement in the liquid. for example, putting water on a drum and playing the drum creates a beautiful water splash form and this is frequently used as a performance. this is visible beauty based on a physical phenomenon. inspired by this, we wanted to find invisible beauty included in this type of physical phenomenon. to realize this, we introduced a high-speed camera as key equipment and have developed a system to realize and shoot such physical phenomena called a “sound vibration system.” the sound vibration system is a new art creation method, which generates various changing shapes of materials ejected up by sound vibration (pang et al. ). we used a high-speed camera with the rate of frames per second, and replayed it with frames per second. this means we expand real time to times. then, the beautiful phenomenon hidden in nature is able to be seen by us directly. the top-down view of the system is illustrated in figure . first, we placed a rubber sheet over the top of a bass speaker and stretched the rubber to give it enough tension. then, we fixed the figure . one of the jackson pollock’s drawings (in public domain). based on the problems included in these two approaches, we think that there should be another way of new art creation somewhere in between these two approaches. we started from the former approach but tried to include more unexpectedness in created forms. in sections and , two methods to realize this are described. . sound of ikebana: an example of created art as one method to create artworks based on the visualization of fluid dynamics, we have developed a method to combine color ink fluid and sound vibration. . . sound vibration system it is well known that applying vibrations to liquids such as water creates movement in the liquid. for example, putting water on a drum and playing the drum creates a beautiful water splash form and this is frequently used as a performance. this is visible beauty based on a physical phenomenon. inspired by this, we wanted to find invisible beauty included in this type of physical phenomenon. to realize this, we introduced a high-speed camera as key equipment and have developed a system to realize and shoot such physical phenomena called a “sound vibration system”. the sound vibration system is a new art creation method, which generates various changing shapes of materials ejected up by sound vibration (yunian pang et al. ). we used a high-speed camera with the rate of frames per second, and replayed it with frames per second. this means we expand real time to times. then, the beautiful phenomenon hidden in nature is able to be seen by us directly. arts , , of the top-down view of the system is illustrated in figure . first, we placed a rubber sheet over the top of a bass speaker and stretched the rubber to give it enough tension. then, we fixed the rubber to make it stable. after that, we poured various fluid materials, with carefully controlled quantities and viscosities, onto the rubber. a rap-top computer was used to generate sound with various wave shapes and frequencies, and the generated sound was fed to the speaker. the vibration of the sound was then delivered to the rubber and to the color paints on it. the color paints were forced to jump from the rubber rapidly. a high-speed camera was used to record the changing shape and another computer connected to the camera recorded this. also, to realize enough brightness for better quality of the shot video, we introduced two w xenon lamps. arts , , x for peer review of rubber to make it stable. after that, we poured various fluid materials, with carefully controlled quantities and viscosities, onto the rubber. a rap-top computer was used to generate sound with various wave shapes and frequencies, and the generated sound was fed to the speaker. the vibration of the sound was then delivered to the rubber and to the color paints on it. the color paints were forced to jump from the rubber rapidly. a high-speed camera was used to record the changing shape and another computer connected to the camera recorded this. also, to realize enough brightness for better quality of the shot video, we introduced two w xenon lamps. figure . top-down view of the sound vibration form system. . . sound of ikebana: created art based on svf by using the sound vibration system described above, we carried out various experiments by changing the type of sound, sound frequency, sound volume, liquid type, liquid viscosity, etc., and based on this, we created an artwork called “sound of ikebana.” in this artwork, sound was used as an energy source which can eject color paint up above the speaker. then a high-speed camera was used to capture the motion of the paints. by expanding the time of the phenomena, we can see the beautiful shape of the paint, which looks like “ikebana,” the japanese flower arrangement. as was described in section . , it is interesting to see the similarity between various forms created by sound vibration and ikebana, a typical traditional japanese culture. this artwork is a combination of the latest technology and the traditional japanese flower arrangement culture. sound of ikebana consists of four short videos, each of which represents one of the four seasons in japan. it uses specific colors to represent flowers in each season (figure ). by utilizing various types of color paints and liquids, we tried to express japanese flowers in each season, such as plum and cherry in spring, cool water and morning glory in summer, red leaves in autumn, and snow and camellia in winter. additionally, we tried to express various color variations such as prayerful colors of buddhism, japanese “wabi” (austere beauty) and “sabi” (elegant simplisity) colors, colors of delicious food, cute colors of “cool japan,” gorgeous colors featuring the new year season, etc. figure . top-down view of the sound vibration form system. . . sound of ikebana: created art based on svf by using the sound vibration system described above, we carried out various experiments by changing the type of sound, sound frequency, sound volume, liquid type, liquid viscosity, etc., and based on this, we created an artwork called “sound of ikebana.” in this artwork, sound was used as an energy source which can eject color paint up above the speaker. then a high-speed camera was used to capture the motion of the paints. by expanding the time of the phenomena, we can see the beautiful shape of the paint, which looks like “ikebana,” the japanese flower arrangement. as was described in section . , it is interesting to see the similarity between various forms created by sound vibration and ikebana, a typical traditional japanese culture. this artwork is a combination of the latest technology and the traditional japanese flower arrangement culture. sound of ikebana consists of four short videos, each of which represents one of the four seasons in japan. it uses specific colors to represent flowers in each season (figure ). by utilizing various types of color paints and liquids, we tried to express japanese flowers in each season, such as plum and cherry in spring, cool water and morning glory in summer, red leaves in autumn, and snow and camellia in winter. additionally, we tried to express various color variations such as prayerful colors of buddhism, japanese “wabi” (austere beauty) and “sabi” (elegant simplisity) colors, colors of delicious food, cute colors of “cool japan,” gorgeous colors featuring the new year season, etc. arts , , of arts , , x for peer review of figure . a scene from “sound of ikebana”. by watching these series of video artworks, the audience would have a feeling of wonder generated by the organic and mysterious figures of the liquid and also its unforeseeable movements. at the same time, the audience would feel the connection of the long history and traditional cultures in asia. to display artworks to many audiences in an effective way, a projection mapping has been frequently used. we carried out the projection mapping of sound of ikebana at singapore artscience museum in . the moving images of sound of ikebana were projected on the wall of the lotus-like artscience museum. the artwork became a part of the city night view, and the whole city was able to appreciate it (figure ). also, the artwork was exhibited in times square in new york during one month in april , using more than digital billboards there (figure ). figure . sound of ikebana projection mapping at artscience museum in singapore. figure . a scene from “sound of ikebana”. by watching these series of video artworks, the audience would have a feeling of wonder generated by the organic and mysterious figures of the liquid and also its unforeseeable movements. at the same time, the audience would feel the connection of the long history and traditional cultures in asia. to display artworks to many audiences in an effective way, a projection mapping has been frequently used. we carried out the projection mapping of sound of ikebana at singapore artscience museum in . the moving images of sound of ikebana were projected on the wall of the lotus-like artscience museum. the artwork became a part of the city night view, and the whole city was able to appreciate it (figure ). also, the artwork was exhibited in times square in new york during one month in april , using more than digital billboards there (figure ). arts , , x for peer review of figure . a scene from “sound of ikebana”. by watching these series of video artworks, the audience would have a feeling of wonder generated by the organic and mysterious figures of the liquid and also its unforeseeable movements. at the same time, the audience would feel the connection of the long history and traditional cultures in asia. to display artworks to many audiences in an effective way, a projection mapping has been frequently used. we carried out the projection mapping of sound of ikebana at singapore artscience museum in . the moving images of sound of ikebana were projected on the wall of the lotus-like artscience museum. the artwork became a part of the city night view, and the whole city was able to appreciate it (figure ). also, the artwork was exhibited in times square in new york during one month in april , using more than digital billboards there (figure ). figure . sound of ikebana projection mapping at artscience museum in singapore. figure . sound of ikebana projection mapping at artscience museum in singapore. arts , , of arts , , x for peer review of figure . sound of ikebana exhibited in times square, new york. . genesis: an example of created art as another method to create artworks based on fluid dynamics, we have developed a method to let fluid and dry ice bubbles interact to create beautiful forms. . . injection of paints into fluid as a basic material to observe fluid behaviors, we chose color paints. in the work described in the previous section, we chose color paints and succeeded in creating various types of beautiful and mysterious forms by applying vibrations to them (pang and tosa ; pang et al. ). therefore, we are familiar with the behaviors of color paints. this time, instead of giving them sound vibrations, we tried to inject them into water. based on various preliminary experiments, we found that color paints injected into water from droppers can create interesting forms that resemble the phenomenon of a volcano eruption or hydrothermal vent (figure ). figure . injection of color paints into fluid. there is some affinity between water and color paints, even in the case of oil-based paints; therefore, injected paints and water mingle rapidly and the water rapidly becomes a kind of “colored water”. as what we want to create are the interesting behaviors of injected paints, this rapid mingling process is not preferable. thus, we tried adding agar into water to increase its viscosity and found that, in the case of water with a certain amount of viscosity, this has the effect of delaying such a mingling process. additionally, we found that the level of viscosity based on the amount of added agar plays an important role by changing the mingling time to some extent. this figure . sound of ikebana exhibited in times square, new york. . genesis: an example of created art as another method to create artworks based on fluid dynamics, we have developed a method to let fluid and dry ice bubbles interact to create beautiful forms. . . injection of paints into fluid as a basic material to observe fluid behaviors, we chose color paints. in the work described in the previous section, we chose color paints and succeeded in creating various types of beautiful and mysterious forms by applying vibrations to them (pang and tosa ; yunian pang et al. ). therefore, we are familiar with the behaviors of color paints. this time, instead of giving them sound vibrations, we tried to inject them into water. based on various preliminary experiments, we found that color paints injected into water from droppers can create interesting forms that resemble the phenomenon of a volcano eruption or hydrothermal vent (figure ). arts , , x for peer review of figure . sound of ikebana exhibited in times square, new york. . genesis: an example of created art as another method to create artworks based on fluid dynamics, we have developed a method to let fluid and dry ice bubbles interact to create beautiful forms. . . injection of paints into fluid as a basic material to observe fluid behaviors, we chose color paints. in the work described in the previous section, we chose color paints and succeeded in creating various types of beautiful and mysterious forms by applying vibrations to them (pang and tosa ; pang et al. ). therefore, we are familiar with the behaviors of color paints. this time, instead of giving them sound vibrations, we tried to inject them into water. based on various preliminary experiments, we found that color paints injected into water from droppers can create interesting forms that resemble the phenomenon of a volcano eruption or hydrothermal vent (figure ). figure . injection of color paints into fluid. there is some affinity between water and color paints, even in the case of oil-based paints; therefore, injected paints and water mingle rapidly and the water rapidly becomes a kind of “colored water”. as what we want to create are the interesting behaviors of injected paints, this rapid mingling process is not preferable. thus, we tried adding agar into water to increase its viscosity and found that, in the case of water with a certain amount of viscosity, this has the effect of delaying such a mingling process. additionally, we found that the level of viscosity based on the amount of added agar plays an important role by changing the mingling time to some extent. this figure . injection of color paints into fluid. there is some affinity between water and color paints, even in the case of oil-based paints; therefore, injected paints and water mingle rapidly and the water rapidly becomes a kind of “colored water”. as what we want to create are the interesting behaviors of injected paints, this rapid mingling process is not preferable. thus, we tried adding agar into water to increase its viscosity and found that, in the case of water with a certain amount of viscosity, this has the effect of delaying such a mingling process. additionally, we found that the level of viscosity based on the amount of added agar arts , , of plays an important role by changing the mingling time to some extent. this finding was important to create the interesting behavior of injected paints. however, basically behaviors of injected paints are based on the diffusing process and, as the time passes, water and paint are mixed based on a one-way process. consequently, it is difficult to generate something unexpected based on this basic method. therefore, some new mechanism of creating unexpected phenomena should be introduced. to realize this, we have introduced the usage of dry ice which is described in the next subsection. . . usage of dry ice as obstacles in fluid pathways based on fluid dynamics study, we have learned that the existence of obstacles in the pathway of fluid motion is the key to generate beautiful and mysterious forms. at the same time, we have learned that such obstacles should not be fixed ones. fixed obstacles give fixed effects to the behaviors of fluid and this process is not effective in generating something unexpected. therefore, such obstacles should move around. also, it is preferable that the moving patterns of such obstacles are unstable or even unexpected. in addition, it is preferable that forms of the obstacles unexpectedly. we carried out various kinds of experiments to determine such obstacles and finally found that the use of dry ice is very effective as obstacles interacting with injected paints. dry ice is the solid form of carbon dioxide. it is used primarily as a cooling agent. its advantages include a lower temperature than that of water ice and not leaving residue. at the same time, dry ice has been frequently used as a material to create mysterious stage effects, as it creates huge amounts of fog when it is added to water. people have been focusing on the effect of fog generation when they use dry ice. however, we have focused on the early process of fog generation. when dry ice is put into water, based on the temperature difference between water and dry ice, rapid vaporization of dry ice occurs. many small bubbles, each of which contains carbon dioxide fog, are generated as the result of vaporization and these small bubbles rise from dry ice from bottom to water surface and finally create fog. watching this process by using a high-speed camera, we have found that such bubbles have interesting forms, with each bubble having a different form. additionally, during the process of a bubble rising up to the water surface, the bubble always changes its form. this phenomenon gives us the impression that each bubble is a kind of living creature (figure ). then, we had an idea that the combination of these bubbles and injected paints described in the previous subsection would be ideal to generate a new type of phenomenon based on fluid dynamics. therefore, we have adopted the usage of dry ice as an obstacle material in the pathway of injected fluid. arts , , x for peer review of finding was important to create the interesting behavior of injected paints. however, basically behaviors of injected paints are based on the diffusing process and, as the time passes, water and paint are mixed based on a one-way process. consequently, it is difficult to generate something unexpected based on this basic method. therefore, some new mechanism of creating unexpected phenomena should be introduced. to realize this, we have introduced the usage of dry ice which is described in the next subsection. . . usage of dry ice as obstacles in fluid pathways based on fluid dynamics study, we have learned that the existence of obstacles in the pathway of fluid motion is the key to generate beautiful and mysterious forms. at the same time, we have learned that such obstacles should not be fixed ones. fixed obstacles give fixed effects to the behaviors of fluid and this process is not effective in generating something unexpected. therefore, such obstacles should move around. also, it is preferable that the moving patterns of such obstacles are unstable or even unexpected. in addition, it is preferable that forms of the obstacles unexpectedly. we carried out various kinds of experiments to determine such obstacles and finally found that the use of dry ice is very effective as obstacles interacting with injected paints. dry ice is the solid form of carbon dioxide. it is used primarily as a cooling agent. its advantages include a lower temperature than that of water ice and not leaving residue. at the same time, dry ice has been frequently used as a material to create mysterious stage effects, as it creates huge amounts of fog when it is added to water. people have been focusing on the effect of fog generation when they use dry ice. however, we have focused on the early process of fog generation. when dry ice is put into water, based on the temperature difference between water and dry ice, rapid vaporization of dry ice occurs. many small bubbles, each of which contains carbon dioxide fog, are generated as the result of vaporization and these small bubbles rise from dry ice from bottom to water surface and finally create fog. watching this process by using a high-speed camera, we have found that such bubbles have interesting forms, with each bubble having a different form. additionally, during the process of a bubble rising up to the water surface, the bubble always changes its form. this phenomenon gives us the impression that each bubble is a kind of living creature (figure ). then, we had an idea that the combination of these bubbles and injected paints described in the previous subsection would be ideal to generate a new type of phenomenon based on fluid dynamics. therefore, we have adopted the usage of dry ice as an obstacle material in the pathway of injected fluid. figure . bubbles generated by dry ice. . . genesis: created artwork based on the interaction between fluid and dry ice we tried to integrate two methods described in sections . and . . firstly, we put a small block of dry ice into water, letting it generate bubbles with carbon dioxide fog inside. then a combination of several color paints were injected into the water. without dry ice-based bubbles, the injected color paints quickly diffused, making the water appear as if colored water. there are two ways to avoid this somewhat uninteresting event. as described in section . , one way that we have figure . bubbles generated by dry ice. . . genesis: created artwork based on the interaction between fluid and dry ice we tried to integrate two methods described in sections . and . . firstly, we put a small block of dry ice into water, letting it generate bubbles with carbon dioxide fog inside. then a combination of several color paints were injected into the water. without dry ice-based bubbles, the injected color paints quickly diffused, making the water appear as if colored water. there are two ways to avoid this somewhat uninteresting event. as described in section . , one way that we have found used agar to arts , , of increase water viscosity to some extent. based on several experiences, we found that there is a certain range of viscosity in which the diffusion of color paints into water occurs slowly. then, under such a condition, we added dry ice into water. as described in section . , various dry ice bubbles were generated as the result of the vaporization of dry ice, where forms of dry ice bubbles are different to each other and even their forms changed continuously while rising up in water to the water surface. then, the injected color paints interacted with these various bubbles and created various complex forms as shown in figure . these created forms were beyond the forms we often see as the result of scientific visualization and look very artistic. arts , , x for peer review of found used agar to increase water viscosity to some extent. based on several experiences, we found that there is a certain range of viscosity in which the diffusion of color paints into water occurs slowly. then, under such a condition, we added dry ice into water. as described in section . , various dry ice bubbles were generated as the result of the vaporization of dry ice, where forms of dry ice bubbles are different to each other and even their forms changed continuously while rising up in water to the water surface. then, the injected color paints interacted with these various bubbles and created various complex forms as shown in figure . these created forms were beyond the forms we often see as the result of scientific visualization and look very artistic. the created artwork called “genesis,” was exhibited in cities including new york, london, and paris, and one of the authors, naoko tosa, did her world tour as japan’s cultural envoy in . one such exhibition carried out in singapore is shown in figure . figure . an example of the interaction between bubbles created by dry ice and injected color paints. figure . exhibition of “genesis” at ikkan gallery in singapore in . . discussion and conclusions in this paper, we proposed new types of media art creation methods and described their details. we have been interested in the art creation process based on the extraction of hidden beauty in nature using technologies. we have noticed and believe that the extraction of hidden beauty is the basis of japanese beauty, as one of the authors, naoko tosa, received many comments/opinions from people all over the world including art curators and art critics saying that they feel there is figure . an example of the interaction between bubbles created by dry ice and injected color paints. the created artwork called “genesis,” was exhibited in cities including new york, london, and paris, and one of the authors, naoko tosa, did her world tour as japan’s cultural envoy in . one such exhibition carried out in singapore is shown in figure . arts , , x for peer review of found used agar to increase water viscosity to some extent. based on several experiences, we found that there is a certain range of viscosity in which the diffusion of color paints into water occurs slowly. then, under such a condition, we added dry ice into water. as described in section . , various dry ice bubbles were generated as the result of the vaporization of dry ice, where forms of dry ice bubbles are different to each other and even their forms changed continuously while rising up in water to the water surface. then, the injected color paints interacted with these various bubbles and created various complex forms as shown in figure . these created forms were beyond the forms we often see as the result of scientific visualization and look very artistic. the created artwork called “genesis,” was exhibited in cities including new york, london, and paris, and one of the authors, naoko tosa, did her world tour as japan’s cultural envoy in . one such exhibition carried out in singapore is shown in figure . figure . an example of the interaction between bubbles created by dry ice and injected color paints. figure . exhibition of “genesis” at ikkan gallery in singapore in . . discussion and conclusions in this paper, we proposed new types of media art creation methods and described their details. we have been interested in the art creation process based on the extraction of hidden beauty in nature using technologies. we have noticed and believe that the extraction of hidden beauty is the basis of japanese beauty, as one of the authors, naoko tosa, received many comments/opinions from people all over the world including art curators and art critics saying that they feel there is figure . exhibition of “genesis” at ikkan gallery in singapore in . . discussion and conclusions in this paper, we proposed new types of media art creation methods and described their details. we have been interested in the art creation process based on the extraction of hidden beauty in nature using technologies. we have noticed and believe that the extraction of hidden beauty is the basis of arts , , of japanese beauty, as one of the authors, naoko tosa, received many comments/opinions from people all over the world including art curators and art critics saying that they feel there is japanese beauty in the artworks developed by her and her team. in section , we discussed this issue by showing several representative japanese artworks and reached the conclusion that, in japanese art history, the extraction of hidden beauty in nature and the expression of it as artworks has been the main stream. we have been interested in fluid behaviors as a natural phenomenon, and have been trying to create artworks by recording fluid behaviors using a high-speed camera. as this area in science is called “fluid dynamics,” in section , the explanation of fluid dynamics and also the relationship between fluid dynamics and art were described in detail. in sections and , two art creation methods based on fluid dynamics were described including their concepts, the methodologies and examples of created artworks. in section , one method of art creation based on fluid dynamics was described. the method is based on the combination of color paints as fluid and sound vibration. we have found that jumping-up color paints, vibrated by sound and shot by a high-speed camera, make beautiful forms and we created an artwork called “sound of ikebana” based on the methodology. both the methodology and the created artwork were described in detail. in section , another art creation method developed by us, which is based on the combination of two processes, was described. the first method is the effect achieved by injecting color paints into water of various viscosities. the second method is to use dry ice as obstacles that interact with the flow of the injected paints and, based on this, create surprising and mysterious liquid forms. by combining these two methods in a relevant way and also by using a high-speed camera to record and visualize the generated phenomena, we can create beautiful, noble, and inspiring forms. we think that there are two ways of creating artworks using fluid. one is a purely scientific process and its aim is to find out beauty in the process of liquid motion as a physical phenomenon. in this case, although the created forms look beautiful, the forms do not look artistic, because there is little unexpectedness in the created forms. another is the usage of liquid as a basic material for creating artwork. here, the basic process of art creation is controlled by an artist. however, in the final art making process, such as paint throwing and dropping, a randomness, that is one of basic natures of physical phenomena, is included to add value to the created artwork. we have found that our proposed methods situate somewhere between these two different processes. its feature is that, on one hand, it can keep pure beauty in physical phenomena. on the other hand, our method removes the feeling associated with too scientific phenomena. therefore, we believe that we have succeeded in creating new type of artworks. of course we understand that it is not adequate to connect fluid dynamics directly to artworks including japanese beauty. we do not want to claim that fluid dynamics-based artworks are the most adequate to express japanese beauty. at this stage, what we want to claim is the following. we have developed several methods to create beautiful forms based on fluid dynamics. as the creation process is closely related to natural/physical phenomenon and also as japanese sensitivity has been closely related to beauty included in natural phenomenon, it was easy for one of the authors, a japanese artist, to include her sensitivity and aesthetics into various art creation processes such as color selection, parameter selection for sound vibration, editing of obtained video and so on. we will further pursue what is japanese beauty and what is the essential art creation process to include japanese beauty. artificial intelligence (ai) technology is progressing and there are various trials to create artworks using ai (du sautoy ). so far, most of the trials are based on learning existing paintings using deep learning method and creating new paintings that are somewhat similar to the existing paintings. such paintings are sometimes criticized as they are not new creations. on the other hand, as our art creation methodology is based on physical/natural phenomena, the combination of our methodology and ai would have a chance to create new types of art. in other words, we may have a new type of ai artists in the st century. arts , , of author contributions: n.t.—contributed to the creation of artistic concept and also the direction of the art creation. y.p.—supported n.t. for the creation of “sound of ikebana.” q.y.—supported n.t. for the creation of “genesis.” r.n.—mainly contributed to the direction of the whole project. also he gave grounding of fluid dynamics based art. funding: this research received no external funding. conflicts of interest: the authors declare no conflict of interest. references feng chen, tomoji sawada, and naoko tosa. . sound based scenery painting. paper presented at the international conference on culture and computing, kyoto, japan, september – . pang, yunian, and naoko tosa. . new approach of cultural aesthetic using sound and image. paper presented at the international conference on culture and computing, kyoto, japan, october – . yunian pang, lian zhao, ryohei nakatsu, and naoko tosa. . a study on variable control of sound vibration form (svf) for media art creation. paper presented at the conference on culture and computing, kyoto, japan, october – . naoko tosa, ryohei nakatsu, pang yunian, and kosuke ogata. . projection mapping celebrating rimpa th anniversary. paper presented at the conference on culture and computing, kyoto, japan, october – . naoko tosa, pang yunian, 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(in japanese) thompson, sarah, and joan wright. . hokusai. boston: mfa publications. wong, eva. . taoism: an essential guide. boulder: shambhara. © by the authors. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /). http://dx.doi.org/ . /j.jcis. . . http://www.ncbi.nlm.nih.gov/pubmed/ http://creativecommons.org/ http://creativecommons.org/licenses/by/ . /. introduction characteristics of japanese art what is japanese beauty? examples of japanese beauty in japanese art visualization of fluid dynamics as a method to create media art sound of ikebana: an example of created art sound vibration system sound of ikebana: created art based on svf genesis: an example of created art injection of paints into fluid usage of dry ice as obstacles in fluid pathways genesis: created artwork based on the interaction between fluid and dry ice discussion and conclusions references branding “real” social change in dove’s campaign for real beauty dara persis murray this article examines the cause branding strategy of the dove campaign for real beauty (cfrb) as a case study in the production and consumption of contemporary popular meanings of feminism, social change, female citizenship, and female beauty in global consumer culture. a feminist semiotic analysis of the print, television, and new media texts that launched cfrb and its brand extensions reveals a juxtaposition in its “real beauty” messaging: signs reference a key opposition in feminist politics (liberation and oppression) while dictating a beauty ideology that encompasses appearance and behavior. further, the texts situate the brand as the site for female activism about the dominant ideology of beauty; this strategy positions the corporation to usurp the feminist role of engendering social change for women and displaces the influential mentoring role away from women who share girls’ everyday lives onto an agent of institutional power. finally, the author argues that this postfeminist-supported campaign encourages the global spread of and individuals’ enlistment in postfeminist citizenship via becoming a “real beauty” who self-brands her neoliberal identity ideologically and materially in the name of empowerment. this “social change” denies agency regarding beauty, sanctions postfeminist citizenship, and holds danger for future meanings and practices of feminism. keywords cause branding; beauty ideal; commodity feminism; postfeminism; interactivity; self-branding in june , the dove movement for self-esteem launched at the g(irls) summit. modeled after the g summit, this convention brought together young women from the same countries represented at the g summit to discuss education, health, and economic initiatives that could stimulate girls’ activism and advancement in their communities. the ideological intersection of the movement (a brand extension of dove’s campaign for real beauty, or cfrb) and the g(irls) summit reflects the complex and often problematic meanings of feminism that circulate in popular culture: the blending of active female citizenship with empowerment via consumption in the marketplace. this paper explores cfrb’s branding strategy, wherein its “real beauty” messaging merges co-opted feminist discourse and “a postfeminist sensibility” (gill , p. ). a feminist semiotic analysis suggests that, under a guise of corporate altruism that democratizes female beauty, cfrb endorses global postfeminist citizenship. the findings q taylor & francis feminist media studies, vol. , no. , – , http://dx.doi.org/ . / . . suggest that cfrb may reflect a social change in the relationship between corporations and audiences that carries perilous meanings for the future roles of feminists and practices of female citizenship in global consumer culture. cfrb offers a rich site for unpacking the production and consumption of popular meanings of feminism, social change, female citizenship, and female beauty at this cultural moment. dove gets the word out dove is a brand of personal care products such as soaps, body washes, and body lotions manufactured by the unilever corporation. since , dove’s mainstay product has been the beauty bar. in , unilever reassessed dove’s marketing strategy with its public relations firm, edelman, and its advertising/marketing agency, ogilvy & mather, to create a unified global image to generate brand loyalty. discussing her view of the global brand, ogilvy’s chairman and chief executive officer shelly lazarus stated, “it means figuring out what is universal about the brand – those things that transcend where it happens to be manufactured, or where it started” (o’barr, lazarus & moreira ). lazarus’s statement indicates that in today’s market, a brand needs to reach audiences’ emotions by building a platform that drives ideological alliance with the corporate identity before the act of material consumption. cfrb was largely shaped by women in industry and as research subjects. female members of ogilvy & mather’s cfrb team included lazarus, two creative directors, an art director, a writer, and producer. lazarus is a graduate of smith college (an all-women’s institution listing numerous feminist icons among its alumni), where she sat on its board of trustees. although lazarus has not publicly aligned herself with feminism, others have identified her as “a strong feminist . . . yet lazarus’s feminist love of economic empowerment prevents her from acknowledging the ways in which capitalism can hurt the powerless” (dyer , p. ). moreover, dove commissioned women to direct its foundational research and conduct much of the campaign’s research. the construction of cfrb was based on dove’s global research study, “the real truth about beauty.” this research involved the participation of thirty-two hundred women, ages eighteen through sixty-four, in ten countries, in a twenty to twenty-five- minute long telephone interview. the study found that less than percent of women feel beautiful; percent want representations of women to reflect diversity through age, shape, and size; and percent want the media to portray beauty as more than physical (etcoff, orbach, scott & d’agostino ). these responses suggested a market for a new philosophy of beauty that was “a great opportunity to differentiate the brand from every [other] beauty brand” (fielding, lewis, white, manfredi & scott ), according to alessandro manfredi, dove’s global brand director. cfrb has been identified as a cause marketing effort (lachover & brandes ), which associates corporate identities with social problems to benefit the corporate image, “distracting attention from their [the corporation’s] connections as to why these social problems continue to exist” (stole , p. ). this article advances that cfrb is a cause branding strategy that merges messages of corporate “concern and commitment for a cause” (cone ) with the participation of women and girls for the same social goals, further concealing corporate aims. in line with their findings, dove announced its challenge to the dominant ideology of beauty: it would feature “real” women and girls of “various ages, shapes and sizes” (campaign for real beauty ). the campaign launched in england in , and was soon exported to canada and the united states; cfrb is currently marketed in thirty-five dara persis murray countries. the branding strategy was executed through television and print advertising, billboards, new media, and national and grassroots outreach. the dove self-esteem fund is a brand extension that serves as the site for in-person and online workshops that provide “self-esteem toolkits” for girls and “parent kits” for mothers/mentors. in the united states, the fund has partnered with multiple national nonprofit girls’ organizations (girl scouts, girls inc., and boys & girls clubs of america) to facilitate these workshops. as an example of cfrb’s international events that engage female audiences, dove “call[ed] on women from the middle east to write about someone they find beautiful and the reasons they see a different kind of ‘real beauty.’ participants could be treated to a luxury five-star treatment for two” (dove exposes the beauty myth ) in return. the dove movement for self- esteem launched in canada and the united states in fall . in the worldwide exportation of cfrb texts, dove positioned their global brand through unified messaging that translates its main idea in images and language suiting the customs of each target geographic area. this analysis interrogates the branding texts launched in the united states: six print texts that communicate the “real beauty” ideology, a television commercial and a viral video (“true colors” and “evolution,” respectively) that promote the fund, and a website that advances the movement. meaning making about “real beauty”: revealing textual meanings through semiotics semiotics is a useful approach for teasing out denotative and connotative meanings in media texts. interrogating signs’ oppositional relations is central to examinations of ideological meaning and power (williamson ), as illuminating differences in meaning leads to an understanding about the unfamiliar by comparing it with the familiar. the semiotic analysis presented here decodes the ways in which cfrb’s signs about “real beauty” communicate meanings of liberation and oppression. it unpacks cfrb’s print texts via their language, logos, and positioning of bodies, thereby linking connotative chains of meaning that exploit similarity and difference (danesi ). to analyze cfrb’s television advertisement and viral video, the latter of which bears similarity to the codes and conventions of television, media scholar john fiske’s ( ) work is helpful. these analytical categories include camera work, lighting, editing, music, casting, setting, costume, make-up, and action. signs develop through social convention and audiences interpret them through learned social codes that cohere to maintain hegemony (seiter ). for semiotician roland barthes, signs contribute to the creation of social myths, which convey social and political meanings (bignell , p. ). the myth’s veracity is shaped by its “distortion or forgetting of alternative messages, so that the myth appears to be exclusively true, rather than one of a number of different possible messages” ( , p. ). at this level of signification, many connotations attach to a sign to comprise a social myth, such as “real beauty.” myth in cfrb is examined as a means of branding the corporation as a feminist advocate for women (although this strategy oppresses women) as well as a process of self-branding women and girls as empowered “real beauties” (although they circulate in culture as signs of corporate identity). a feminist perspective on beauty in the twentieth and twenty-first centuries, the beauty and fashion industries have produced powerful media images communicating the dominant ideology of female beauty branding “real” social change as ultra-thin, tall, sexual bodies. consumption of these images has resulted in a cultural norm of women and girls disciplining their bodies (bordo ). the beauty industry’s discourse connects ideological and physical nonconformity to the dominant ideology with a woman’s inability to fulfill her gender role or experience happiness (bartky ). the struggle of women and girls to physically emulate media images has manifested itself in eating disorders and body image issues, while the lack of a fulfilled identification may result in low self-esteem (kilbourne ). dove’s stated call to arms echoes feminist and feminist media studies scholarship that addresses how representations in popular culture convey often-problematic meanings of gender and beauty. in its advocacy of women’s rights and egalitarian roles, the feminist position argues for social change of oppressive social structures (dworkin ). by contrast, the postfeminist position contends that gender equality and female empowerment have been achieved in the public sphere. postfeminism has immense power in western culture, as noted by feminist media studies scholar rosalind gill, who names our current time a “postfeminist media culture” ( , p. ). significantly, she advances that postfeminism can be interpreted as “a sensibility” ( , p. ) whose messaging includes: the notion that femininity is a bodily property; the shift from objectification to subjectification; the emphasis upon self-surveillance, monitoring and discipline; a focus upon individualism, choice and empowerment; the dominance of a makeover paradigm; the articulation or entanglement of feminist and antifeminist ideas . . . and an emphasis upon consumerism and the commodification of difference. (rosalind gill ) the postfeminist position easily aligns with corporate interests, situating messages of women’s freedom in the marketplace as “empowered consumer[s]” (tasker & negra , p. ). this identity lies at the intersection of consumerism and neoliberal governmentality, thereby separating meanings of female citizenship from civic engagement (mcrobbie , p. ). the emergent neoliberal postfeminist citizen links meanings of empowerment and choice to ideological and material consumption. the postfeminist citizen’s pursuit of beauty engages her consumer power and self- governance, aligning her identity with the goals of institutional power. in postfeminist media culture, the body is a site of attention for the postfeminist citizen since it is promoted as integral to female identity (gill , p. ). consumption of the dominant ideology of beauty involves absorbing representations and meanings of hypersexual women and, increasingly, girls. agreement with these messages may make it difficult for postfeminist citizens to understand their sexuality in “healthy, and progressive ways” (durham , p. ). this feminist analysis will consider the political, social, and economic meanings in cfrb’s texts and address how female identity may be shaped as postfeminist citizenship through the myth of “real beauty.” self-branding by embracing popular feminism a strategy for accomplishing audience identification with texts is the co-option of discourse; importantly, such appropriation highlights social issues as a means of generating sales (danesi ). alignment with co-opted subcultural signs allows consumers to think of themselves as insurgents; yet, since their rebellion occurs through consumerism, they do not “pay the social price of true non-conformity and dissent” (danesi , p. ). dara persis murray sociologist robert goldman terms this tactic “commodity feminism,” wherein advertisers attempt “to reincorporate the cultural power of feminism” (goldman , p. ) and, in so doing, depoliticize the feminist message. commodity feminism takes on new meaning in a consumer culture characterized by branding, a marketing strategy that trademarks corporate identity and is a “social, economic and existential reality” (arvidsson , p. ). branding utilizes techniques of persuasion to make the brand become a seamless part of individuals’ everyday lives. media scholar adam arvidsson argues that a brand’s value arises from its strategies that “manage and program human communication and appropriate the ethical surplus – he common – that it produces as a sort of value” (arvidsson , p. ). thus, when people purchase a brand based on the corporate identity that has been attached to it, socialization occurs through a common association with the brand. their socialization, then, is mediated through the brand’s role in their lives, and their attachment to the brand secures its place in culture and social networks. branding enlists audiences to support a corporate brand identity that is managed by the corporation to produce its desired outcome. in turn, audiences’ agency is limited by corporate desires because “brands are a kind of de-territorialized factory where the productive mass intellectuality and the new forms of surveillance” (arvidsson , p. ) converge in consumer culture. importantly for this study, cause branding is a specific type of branding that blends corporate and individual identities through brand communication and audience participation. cause branding “falls at the intersection of corporate strategy and citizenship and is fast becoming a ‘must do’ practices [sic] for the st century” (cone ), therefore positioning corporations to implement their identities to attract and retain consumers through a depth of involvement that draws on their emotions, actions, and identities to drive brand commitment. it is important to consider the practice of self-branding when thinking about girls and women who consume cause branding messages. while media studies scholars have examined the meanings of textual signs, a study of current consumer culture entails an exploration of the ways in which individuals are encouraged to become a self-branded “commodity sign” (hearn , p. ) using “the narrative and visual codes” (hearn , p. ) promoted by institutional power (corporations, advertisers, and so on). self-branding suggests that the audience-as-sign is a cultural product that sits at the nexus of consumed media messages, social interactions, and identity development shaped by postfeminist media culture. this analysis considers how cfrb’s meanings of popular feminism and social change convey the message that audiences should self-brand as postfeminist “real” beauties. the current study: liberation and oppression in “real beauty” this section presents a feminist semiotic analysis of cfrb’s print, television, and new media texts. these branding texts will be presented in chronological order of their entry into popular culture. the myth of “real beauty” will be teased out through a textual interrogation of the theme of liberation and oppression. cfrb print texts cfrb’s texts integrate feminist politics from the three waves through the pictorial signs of “real” women and the use of feminist discourse to foster audience identification branding “real” social change based on physical attributes, age, and generational feminist politics. the pictorial signs of women signify their age, which corresponds with a feminist wave, and all the women are photographed against a white background. these images inaugurate the campaign’s mission with representations of five women of distinctly varied ages, signifying a unification of women from the three waves. the first word of cfrb—“campaign”—acknowledges a political intention. linguistic signs in the cfrb texts connote the politics of the feminist waves: specifically, the first wave’s focus on suffrage; the second wave’s focus on collective—“we”—political action by women; and the third wave’s focus on individual difference—in gender, ethnicity, race, etc.—or micro-politics. the print launch comprised six images: portraits of five women (three close-ups of faces and two body shots at a distance) and one composite picture of them. the five women pose with questions that address the dominant ideology of beauty; each question offers two options as a response. the cfrb manifesto accompanies the composite image, stating: for too long, beauty has been defined by narrow, unattainable stereotypes. it’s time to change all that. because dove believes real beauty comes in many shapes, sizes, colors and ages. it’s why we started the campaign for real beauty. and why we hope you’ll take part. together, let’s think, talk, debate and learn how to make beauty real again. cast your vote at campaignforrealbeauty.com. (dove manifesto ) the three close-up photos represent women from each wave. their images are accompanied by ballot boxes next to descriptive labels, posed as questions: “wrinkled? wonderful?” (first wave), “gray? gorgeous?” (second wave) and “flawed? flawless?” (third wave) the dark-skinned ninety-ish woman wearing a colorful headscarf smiles, with the text beside her asking, “will society ever accept old can be beautiful?” this query signifies the difficulties involved in changing societal views regarding the role of women (first wave; figure ). the smiling fifty-ish caucasian woman wears a black turtleneck and, looking over her shoulder at the audience, the text beside her raises the only question of those in this set that invites discussion, rather than a yes/no response: “why aren’t women glad to be gray?” this question signifies the consciousness-raising ideology of dialogue relevant to her era (second wave). the text beside the twenty-ish, red-haired caucasian woman, wearing a white tank top, poses a question that seemingly derives from her freckled appearance, “does beauty mean looking like everyone else?” this inquiry signifies the ideology of difference in her wave (third wave; figure ). additionally, two women belonging to the third wave are photographed from head to thighs and are presented next to the ballot box signifier. one image (“half empty? half full?”; figure ) depicts a slim, smiling, short-haired, small-breasted black woman in a white tank top and jeans with her hands in her back pockets; the text beside her breast questions, “does sexiness depend on how full your cups are?” this phrasing suggests optimism or pessimism, an intertextual reference to the rhetorical expression, “is the glass half empty or half full?” the other image (“oversized? outstanding?”; figure ) depicts a full-figured, smiling, large-breasted caucasian woman in a strapless black cocktail dress with hands crossed behind her head; the text, positioned at her hips, asks, “does true beauty only squeeze into a size ?” both of their confidently smiling visages connote an optimistic, “real beauty” answer to the ballot box question posed next to them. the full-figured woman has a confident posture, with arrows created by her arms and elbows that direct the audience to the bare skin above her breasts and on her arms. the thin woman draws attention to her lean body by positioning her hands at her back, which highlights her small circumference; dara persis murray campaignforrealbeauty.com her mid-section, clothed in a white tank top, blends in with the background, again highlighting her slim physique. likewise, the freckled woman (figure ) reveals her thin upper body through a barely-there tank top, its placement offering another meaning of “flawed? flawless” as referencing her breast size. the representations of these third-wave women problematize the cultural issues of breast size and body weight that signify female sexuality. women, regardless of race or class, have attempted to resolve self-esteem problems arising from a perceived deficit in these sites on the body through potentially self-harming diets and/or plastic surgery. the casting of these women, however, based on their physical attributes, inherently objectifies these images, as their bodies are employed by dove to promote ideological and economic consumption by audiences. the composite representation of all five women is accompanied by the cfrb manifesto. their images appear in a strip above the linguistic signifiers, beginning on the left with the first-wave woman. her image stands apart from the group, as she is separated figure “wrinkled? wonderful?” copyright ogilvy & mather. branding “real” social change by more space and appears to be of a slightly larger size. in addition, her representation is the only one that differs from the individual ballot box image, as here she is cropped mid- breast and thus some of her clothing is visible; also, in this composite image her head is not cropped. her bright headscarf, white strapless top with a black horizontal line (the only clothing that blends black and white), front facing body positioning, and location as the first woman in the strip of images, all draw attention to her image as the most dominant, connoting her wave’s leadership role in the feminist movement. in relation to her pictorial sign, the cfrb mission statement connotes that dove, like the first-wave feminists, is an agent of social change. however, the corporate message is visually constructed as more important than the women: the paragraph of copy occupies more space on the page than all the women together, the text occupies more vertical space than the strip of photos, and the copy concludes with a blue color whose length and vibrancy are more visually compelling than the women. further, this blue copy relays information about dove and cfrb: the campaign website, the dove icon, and a request to “cast your vote.” the copy emphasizes dove as the organizer, catalyst, and vehicle for change: “it’s time to change all that . . . it’s why we started the campaign for real beauty.” cfrb’s texts connote a figure “flawed? flawless?” copyright ogilvy & mather. dara persis murray hegemonic relationship between the “real” women (who represent the liberation of women) and the corporation (as the site for the elimination of women’s oppression). in this sense, the texts are a means to position dove to usurp the power of women and the feminist movement in this mission of “real beauty.” cfrb’s strategy raises questions about the politics of women’s participation in the campaign, as will be discussed. the message of “real beauty” in these texts functions as a social myth wherein the denotative signs of liberation oppose the connotative signs of oppression in the depictions of “real” women. the central meaning of “real beauty” in these texts is connected to a voting device; the linguistic sign “cast your vote” connotes the feminist value of suffrage, however, cfrb is not an election. by tallying the votes on publicly displayed interactive billboards and on the cfrb website, the women become objects for approval or disapproval by the “real” judgment of global audiences, with potentially disempowering consequences for the “real” women. moreover, cfrb’s oppressive construction of these signifiers—wherein the voter is able to select only one option—does not allow for debate, figure “half empty? half full?” copyright ogilvy & mather. branding “real” social change and also limits the audience’s freedom of expression. such devices facilitate dove’s authority to oppress “real women” and the audiences who identify with and even judge them. self-esteem fund: television and viral video dove took cfrb’s messaging “a step further and [focused on] talk about self-esteem” (branding evolution ) by launching two texts in to brand the dove self-esteem fund, which was established by and is primarily financed by unilever/dove. these texts encourage ideological identification for girls and adult female audiences (mentors/- mothers). girl audiences may identify with the “real” girls in cfrb’s television advertisement and viral video through sharing their physical attributes, ages, and, significantly, their emotional states. these texts are designed to arouse emotions against the dominant ideology of beauty and garner support for “real beauty.” the mentors’/mothers’ figure “oversized? outstanding?” copyright ogilvy & mather. dara persis murray identification is mobilized through acceptance of the fund’s leadership and mission: to save girls’ psychological and physical health via an emphasis on “self-esteem” (a crucial component of the “real beauty” ideology). women can also economically bond with dove by making donations to the fund. “true colors” debuted during the february superbowl xl game, at a cost of $ . million dollars for forty-six seconds. the spot ran during this time to make contact with the largest audience possible, in keeping with dove’s goal (which was achieved) of reaching one million young girls by . in “true colors,” dove represents itself as a facilitator and problem-solver, declaring: “let’s change their minds/we’ve created the dove self-esteem fund/because every girl deserves to feel good about herself/and see how beautiful . . . she really is/ help us . . . get involved at” the cfrb website. in “evolution” (launched eight months later), dove establishes its credibility as a leader by exposing the construction of unattainable beauty at the initial site of production (the studio set) and in the technological space (the software program, photoshop). at the end of the text, dove asks girls, mothers, and mentors to “take part in the dove real beauty workshop for girls” through the cfrb website. “true colors” offers a range of emotions in the expressions of “real” girls of various sizes and ethnicities. the emotional song, “true colors,” is performed by the girl scouts chorus. at first, the girls’ faces reflect innocence or ambivalence, bolstered by linguistic signs connoting feelings of victimization—“hates her freckles,” “thinks she’s ugly,” “wishes she were blonde,” “afraid she’s fat”—because they do not meet the dominant ideology of beauty. the lyrics simultaneously elevate the poignant portraits and offer an intimate relationship with the person (“i”) in the music and the girls in the text: “show me a smile then, don’t be unhappy, can’t remember when, i last saw you laughing, if this world makes you crazy and you’ve taken all you can bear, you call me up, because you know i’ll be there.” halfway through the video, an emotional shift occurs following the encouraging syntagm, “let’s change their minds” against a white background. the lyrics also become positive: “and i’ll see your true colors shining through.” accompanying this phrase is a group of smiling girls euphorically pumping their hands in the air, an intertextual reference to the feminist iconic image of “rosie the riveter,” whose slogan was “we can do it!” another phrase, “we’ve created the dove self-esteem fund,” appears next, also against a white background. smiling girls appear throughout the rest of the text, accompanying dove’s announcement of leadership via the fund and the lyrics: “i see your true colors, and that’s why i love you, so don’t be afraid, to let them show, you’re beautiful like a rainbow.” the white background on which the pivotal text for the film’s message appears signifies light, symbolizing dove as the caring narrator (“i”) and the ray of light illuminating the public perception of female beauty and girls’ “real beauty.” “evolution” launched on youtube at no cost to dove or ogilvy & mather other than its production expenses. near its commencement, a screen displays the words “a dove film.” although dove’s “film” is brief (seventy-four seconds) and not presented in a traditional cinematic space (like a movie theater), this label allows dove to appropriate the aims of feminist documentary filmmaking, which serves as a medium for raising social awareness (byerly & ross ). two types of feminist filmmaking emerged during the second wave: one offered alternative images to gender stereotypes in the service of self-expression, and the other deconstructed the film medium “to expose the ideological (patriarchal) apparatus beneath” (de lauretis paraphrased by byerly & ross , p. ). cfrb employs both: “true colors” (although not stated as a “film”) offers an alternate branding “real” social change component of beauty (self-esteem) wherein self-perception of beauty does not rely on conformity to the social standard, while “evolution” exposes the ideology of beauty through its deconstruction of a media text. “evolution” depicts a woman’s makeover using the tools (physical, technological) that are employed by the beauty industry to transform a “real” woman into a supermodel. the subject appears to be in her twenties and sits on a stool, staring without affect into the camera. bright lights suddenly turn on; the footage speeds up in a choppy, fast-forward simulation; and music plays in synchrony with the rapid projection of images. the woman is presented as a site of work for make-up artists and hair stylists. during the transformation, the camera zooms in on her face, removing any indicators of her tank top to imply a state of undress. the image is manipulated using photoshop, and her final representation as the dominant beauty appears on a billboard that two girls walk past and briefly acknowledge, connoting acceptance of the manufactured image as a cultural norm. the syntagm at the conclusion of the film, “no wonder our perception of beauty is distorted,” implicitly acknowledges a social problem that relates to the dominant ideology. however, the ambiguous use of the word “our” suggests that dove (and perhaps other corporations) as well as women, men, and countless other factors are culpable for the problematic of beauty. finally, the logo that appears with the syntagm, “the dove self- esteem fund” shows the upward flight of three blue doves in ascending size (from small to large). the color blue symbolizes “trust, loyalty, wisdom, confidence, intelligence, faith, truth, and heaven” (color wheel pro ). the three doves perhaps symbolize the corporation/institutional power, the mother/mentor, and the daughter/girl, although which set of doves symbolizes which conceptual pair is ambiguous. their upward direction connotes unity and positive direction for the future. however, this optimistic sign diverts from the messaging, which positions the corporation to usurp the feminist role of engendering social change for women and displaces the influential role of the women who share girls’ everyday lives onto institutional power. moreover, through the fund, dove asks mothers/mentors and girls to endorse the oppressive female role as an ideological and material consumer. dove movement for self-esteem the dove movement for self-esteem is primarily an online branding strategy through social media and the corporate website. achieving online popularity (over ten million views) and more popular discourse for the brand than “true colors” (and for minimal cost), the movement may be an effort drawing on the success of “evolution” as a low cost, high impact text. it is a site of interactivity, a critical process for understanding the agency and subjectivity of users. the movement continues cfrb’s global conversation about beauty with the aim of “building a world where women everywhere have the tools to inspire each other and the girls in their lives” (about the movement ). the movement and cfrb share the same ideology but use slightly different terms to suggest their own uniqueness and, perhaps, reinvention. for instance, cfrb does not appear on the movement’s site, but a link is offered to dove’s homepage on which cfrb is listed (though not prominently). further, cfrb and the movement have partnerships with the same nonprofit organizations but call them by different names (for cfrb, “self-esteem partners”; for the movement, “partner organizations”). much like the political intention in “campaign,” the word “movement” dara persis murray denotes a group that engages women’s participation (like the feminist movement). this terminology displaces the feminist role more overtly than the fund texts. the movement emphasizes users’ participation as a prerequisite for liberation, which may be likened to collective activism (similar to the second wave). the movement brings together the “real beauty” ideology from cfrb’s print texts with the fund’s positioning of dove as the site for women’s and girls’ activism. the centerpiece of the movement is acceptance of its mission, which is executed when women and girls acknowledge their participation by signing a “declaration” to “join the movement.” a declaration denotatively affords power to the audience by offering the opportunity to make a choice and assert oneself. yet the movement’s language communicates a hegemonic relationship between the corporate leader and its followers, asking users to join “our movement,” “our vision,” and “our cause.” the declaration itself amounts to providing their email address, first and last name, zip code, and age, as well as an answer to an “optional” question: “what advice would you give to your year old self? we’ll collect these messages and deliver them to girls to build self-esteem in the next generation” (our vision: join us ). minimization of the only question that may stimulate self-care suggests that the purpose of the declaration is for unilever/dove to gather demographic information. after all, corporations can “expand revenue opportunities, broaden markets, and reinforce viewer commitments” (jenkins , p. ) by using new media “designed to be more responsive to consumer feedback” (jenkins , p. ). that the movement may be using the declaration to create a list of consumers under the guise of participation for social change is not surprising: cfrb was formulated on the findings from a global research study and dove has conducted numerous global and national studies throughout the campaign. the movement can be seen as a form of market research, and the movement’s participants are its research subjects. the work of media studies theorist mark andrejevic is of particular importance here, as he contends that it is critical to question the politics of participation by users, who may be involved in “the labor of detailed information gathering and comprehensive monitoring . . . in the name of their own empowerment . . . and to view such participation as a form of power sharing” ( , p. ). scholarship on dove’s user-generated marketing raises issues of users’ labor on behalf of the brand (duffy ) and users’ discourse may support the patriarchal view that women’s role is to pursue the dominant ideology (lachover & brandes ). in light of these voices, the movement’s declaration serves as a contractual agreement between audiences and the “real beauty” ideology, whose potential for the liberation of women and girls is questionable. the myth of “real beauty” may be shaping subjectivities by enlisting audiences’ labor, as will be discussed next. producing a postfeminist campaign and self-branded postfeminist citizenship cfrb and its brand extensions (the fund and the movement) created and advanced a myth of “real beauty.” this ideology mandates female audiences to practice psychological self-improvement and physical subjectification as a means of liberation from the dominant ideology of beauty. this section explores the production (concentrating on the politics of women’s participation in cfrb) and potential consumption (in connection with self- branded identity and postfeminist citizenship) of “real beauty” to consider its promise to facilitate audience liberation. branding “real” social change in addition to the aforementioned participation of women from ogilvy & mather, cfrb’s partnership with the woodhull institute for ethical leadership further highlights women’s involvement in this branding strategy. woodhull is a nonprofit women’s organization named after feminist victoria woodhull. its website describes its partnership by employing the key words of feminist activism—“social change”: “the woodhull institute of ethical leadership has partnered with the dove cfrb to share success building tools through online training sessions that promote ethical development and empower women to act as agents of positive social change” (woodhull ). of note, woodhull’s co-founder and most public figure is naomi wolf, who may be known to popular audiences for her bestselling critique of the beauty industry, the beauty myth. three years later, wolf advocated a postfeminist position in her subsequent (and lesser known) book. however, for audiences who remember wolf from her argument in the beauty myth and are not versed in postfeminism, this partnership may pose conflicting meanings of feminist involvement with the beauty industry. as one journalist notes, “to go from writing the beauty myth to touring with dove and singing its praises is a big jump” (m.k. johnson ). at the same time, the author optimistically queries whether wolf is actually “spreading her message about the hypocrisy of the beauty industry, all on dove’s dime? savvy audience members would certainly catch the irony, and dove can laugh all the way to the bank. everybody wins” (m.k. johnson ). several “self-esteem” partners (nonprofit girls’ organizations that draw on feminist ideologies) similarly bolster cfrb/dove’s credibility to audiences. the participation of these female-focused groups extends the brand into community spaces in a grassroots way that may read as “feminist” for popular audiences. these groups thereby function as a kin network that aids in the development of a cfrb community. the strategy surrounding dove with these partnerships may operate to reduce popular attention to unilever’s other brands; after all, unilever manufactures slimfast (a diet plan), fair & lovely fairness cream (a skin lightening product), and axe deodorant (whose advertisements, targeted at men, portray objectified women). unilever’s ownership structure suggests it is a site of fractured ideological credibility that circulates knotty popular meanings of feminism and social change. by asking girls and women to partner with the corporate ideology in a similar manner as the aforementioned organizations, the movement potentially enlists global postfeminist citizenship through the support of yet another oppressive beauty ideology. by signing the declaration, girls and women work to become neoliberal subjects who accept responsibility to develop and perform dove-approved “self-esteem” behaviors (requiring self-judgment and self-monitoring of one’s emotional state) that are integral to the pursuit of “real beauty.” joining the movement aligns its participants with neoliberal governmentality and, thus, postfeminist citizenship, as “self-esteem is a technology of citizenship and self- government for evaluating and acting upon our selves so that the police, the guards and the doctors do not have to” (cruikshank , p. ). finally, audiences’ compliance with the “real beauty” ideology allows dove to distance itself from its cultural role as a producer of the dominant ideology by placing the responsibility for women’s and girls’ lack of self- esteem on themselves. cfrb’s cause branding strategy thereby engages female citizenship through consumerism. this fusion of participation in and consumption of “real beauty” suggests that female audiences will voluntarily shape their identity through the practice of self- branding. by branding themselves as “a real beauty,” girls and women derive their identity from internalization of the meanings and representations produced by dove to align themselves with the postfeminist citizen who obeys cfrb’s rules in the name of dara persis murray empowerment. becoming “a real beauty” necessitates ideological and material labor on the self that originates from acceptance of the “real beauty” myth: support of cfrb’s hegemonic views of female beauty, agreement with dove as the site for social change and female activism about beauty (even if it displaces the roles of feminists, mothers, and mentors in individuals’ lives and in cultural ideology), work to achieve dove’s meaning of self-esteem, and embrace of women’s traditional role as consumers. while cfrb denotatively associates “real beauty” with diversity and independence, its connotative signs stand in stark contrast to those values. in fact, self-branding oneself as “a real beauty” enlists conformity: labor to become part of an “inventor[y] of branded selves” (hearn , p. ) from which dove profits “by packaging, branding them, and selling them back to themselves” (hearn , p. ). moreover, regardless of their awareness as self-branders, women and girls—by virtue of this process—become “global value subjects. they are product, producer, and consumer, but they do not control the means of their own distribution” (hearn , p. ). by signing the movement’s declaration, women declare themselves postfeminist citizens whose labor and “real” identity serve the aims of institutional power. the rationale for women’s and feminists’ support of cfrb may lie in the postfeminist belief that contemporary women are consumers with agency. or, feminists might welcome cfrb’s representations as a positive change in a mediascape that is otherwise saturated with the dominant ideology of beauty. it is important to stress, however, that the feminist task is to realize social change that revolutionizes social structures, not to support corporate strategies that seek audiences’ brand attachment. while cfrb and the movement do not liberate female audiences from an oppressive ideology of beauty, women’s (and men’s) participation in cfrb may have liberated cfrb/dove from “a ‘cluttered’ [media] environment in which there are more and more messages [that] must have [to find] a way to break through the attendant noise” (jhally , p. ) by developing a postfeminist-supported branding strategy. ultimately, it seems that “who wins” in cfrb’s effort is the corporation. at first, cfrb resulted in enormous financial success for dove and industry acclaim for ogilvy & mather and edelman public relations, which spearheaded cfrb’s marketing. sales figures indicate that dove’s revenues increased following its launch: . percent in and . percent in (neff ). in , cfrb swept the highest awards in the advertising industry and its sister industry, public relations. in , however, sales growth dwindled to . percent (neff ), and industry pundits questioned whether sales were connected to advertisements for dove’s pro-age product line (featuring unclothed women over age fifty) that perhaps “went a step too far in embracing aging in all its naked, wrinkled and sagging glory” (neff ). the same year, controversy over the realness of cfrb’s texts may have impacted sales when retoucher pascal dangin implied in an interview that he had altered the pro-age texts (collins ). while dove denied any textual modifications and dangin retracted his statements, the public realization that there had (or could have) been retouching may have generalized to a lack of textual and brand authenticity. in , although the “brand reportedly gained $ . billion in value” (molitor ) since cfrb’s launch, dove’s unhappiness with its sales led to a re-assessment of cfrb. the movement may be cfrb’s tactic to restore its integrity with audiences to bolster sales. moreso than previous cfrb strategies, the movement incites ideological brand commitment through focusing on women’s “depth of involvement, the engagement, the participation and the commitment of moving people to take action” (molitor ). the movement may also be a branding “real” social change way for dove to publicly emphasize the brand bond with consumers, thereby minimizing the role of industry insiders. “real beauty” is an oppressive ideology that reinforces the value of female beauty and its pursuit by garnering women’s agreement with its values of ideological and material consumption. at its core is a paradox: while apparently decrying it, “real beauty” embraces conformity to hegemonic beauty standards through both corporate instigation for brand attachment and women’s striving to be part of what they may feel is a positive beauty ideology. “real beauty,” then, is “diluted by its contradictory imperative to promote self- acceptance and at the same time increase sales by promoting women’s consumption of products that encourage conformity to feminine beauty ideology” (johnson & taylor , p. ). cfrb’s “real” women, whose beauty deviates from the beauty norm in size and/or color, lend credibility to the campaign and invite female audiences to self-brand as a “real beauty”; yet, this identity aligns with being a consumer of a corporate brand strategy that positions itself in the feminist role as an advocate for social change that promises to empower women. the stakes are high for audiences who agree with cfrb’s meanings of “real beauty,” and may intensify when such popularized meanings of empowerment are drawn on and reinforced as cultural norms by future brands. in addition, cfrb does not work to create awareness about female beauty as a social issue that has institutional underpinnings (for example, concretely addressing the links between eating disorders, body image issues, and beauty industry discourse/images). like cause marketing, this cause branding strategy “is merely a cleverly disguised ploy to mask some of the fundamental problems for which the very same marketing forces are directly or indirectly responsible” (stole , p. ). within this consumer context, commercial connotations are attached to popular messages and practices of philanthropy (stole ). there is much work to be done to arrive at a strong collective feminist voice of what empowering female beauty means for current and future audiences. as feminist media studies scholar angela mcrobbie suggests, this action may “entail the resuscitation and re- conceptualization of feminist anti-capitalism” ( , p. ). the “real beauty” myth serves as a cautionary example of how institutional messaging about the democratization of female beauty connotes a hegemonic relationship between the corporation and female audiences, reframes the dominant ideology of beauty, and endorses the spread of postfeminist citizenship. cfrb’s partnership between female cultural producers and a corporation is problematic at best. conclusion there is a complicated relationship between corporate strategies and the production and consumption of popular meanings of feminism, social change, and female citizenship in postfeminist media culture. this study has argued that cfrb’s cause branding strategy perpetuates an oppressive ideology of “real beauty” requiring a behavior (“self-esteem”) that underscores neoliberal self-improvement benefiting the corporation’s power. cfrb’s textual signs revealed a significant theme in feminist politics (liberation and oppression) in the communication of the “real beauty” ideology, whose consumption may involve women’s and girls’ self-branding as “a real beauty” and postfeminist citizenship. further research might unpack female audiences’ meanings about “real beauty” and self-branding practices, as well as cfrb’s messaging of “real beauty” and its interpretations in non-english speaking countries. dara persis murray notes . countries represented at the g(irls) summit and the g summit are argentina, australia, brazil, canada, china, france, germany, india, indonesia, italy, japan, mexico, russia, saudi arabia, south africa, south korea, turkey, uk, usa and the european union. . women who participated included dr. jennifer scott and heidi d’agostino of research firm strategyone; dr. nancy etcoff, harvard psychologist; and dr. susie orbach, author of fat is a feminist issue. . see “welcome to dove” for a list of countries. . industry insiders confirmed that there is no single database for global cfrb texts. a search of texts in the major markets where cfrb was created (the uk, the us, and canada) found minor differences in the images and language that did not substantially alter the messaging. the us texts were selected since they are among the first set of texts, the united states is a major market, and they were accessible. this analysis thus focuses on the us texts. . the feminist movement is generally regarded as comprising three “waves” whose dates are as follows: the first wave occurred from the late nineteenth century to the s; the second wave occurred from the s to the s; the third wave began in the s and characterizes the present time. . the author was granted permission to reproduce the first-wave and third-wave portraits and third-wave body shots, but not the second-wave portrait and composite portrait of the women (these images, accordingly, are not included in the article). . the uk version says, “fat? fit?” and the canadian version asks, “fat? fab?” these sentiments are strikingly similar to the us version. . “beyond stereotypes” ( ) collected information from , girls and women from ten countries; “beauty comes of age” ( ) surveyed , women from nine countries; and “real girls, real pressure” ( ) surveyed , american girls. . awards include: cannes advertising’s grand effie award, cannes’ film grand prix and cyber grand prix, global campaign of the year by advertising age, consumer launch campaign of the year by pr week, and best of silver anvil award from the public relations society of america. references about the movement (web page) ( ) dove/unilever, [online] available at: http://www. dovemovement.com/movement/about ( november ). andrejevic, mark ( ) ispy: surveillance and power in the 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( ) ‘philanthropy as public relations: a critical perspective on cause marketing’, international journal of communication, vol. , pp. – . tasker, yvonne & negra, diane ( ) ‘introduction: feminist politics and postfeminist culture’, in interrogating postfeminism: gender and the politics of popular culture, eds yvonne tasker & diane negra, duke university press, durham, pp. – . true colors (videorecording) ( ) [online] available at: http://video.google.com/videoplay?- docid¼ # ( june ). welcome to dove (web page) ( ) [online] available at: http://www.dove.com/?ref¼dove ( october ). williamson, judith ( ) decoding advertisements: ideology and meaning in advertising, marion boyars publishers, new york. woodhull (web page) ( ) the woodhull institute for ethical leadership, [online] available at: http://www.woodhull.org/gallery/index.php ( june ). dara persis murray is a doctoral candidate in journalism and media studies at rutgers university, where she also completed a certificate in women’s and gender studies. e-mail: darapm@rci.rutgers.edu branding “real” social change http://lucire.com/insider/ /is-naomi-wolf-pulling-punches-for-doves-real-beauty-campaign http://lucire.com/insider/ /is-naomi-wolf-pulling-punches-for-doves-real-beauty-campaign http://www.hubmagazine.com/html/ /may_jun/womanwise.html http://www.hubmagazine.com/html/ /may_jun/womanwise.html http://muse.jhu.edu.proxy.libraries.rutgers.edu/ http://muse.jhu.edu.proxy.libraries.rutgers.edu/ http://www.dovemovement.com/declaration/sign http://www.dovemovement.com/declaration/sign http://video.google.com/videoplay?docid= # http://video.google.com/videoplay?docid= # http://www.dove.com/?ref=dove http://www.woodhull.org/gallery/index.php copyright of feminist media studies is the property of routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. however, users may print, download, or email articles for individual use. irb-th- / july, . enhancement of preasymptotic effects in inclusive beauty decays b. guberina∗, b. melić†, h. štefančić‡ theoretical physics division, rudjer bošković institute, p.o.box , hr- zagreb, croatia abstract we extend voloshin’s recent analysis of charmed and beauty hyperon decays based on su ( ) symmetry and heavy quark effective theory, by introducing a rather moderate model-dependence, in order to obtain more predictive power, e.g. the values of lifetimes of the (Λb, Ξb) hyperon triplet and the lifetime of Ωb. in this way we obtain an improvement of the ratio τ (Λb)/τ (b d ) ∼ . and the hierarchy of lifetimes τ (Λb) ' τ (Ξ b ) < τ (Ξ−b ) < τ (Ωb) with lifetimes of Ξ−b and Ωb exceeding the lifetime of Λb by % and %, respectively. pacs: . .mr, . .he, . .hg, . .jh keywords: beauty baryons, lifetimes, inclusive decays, four-quark operators ∗guberina@thphys.irb.hr †melic@thphys.irb.hr ‡shrvoje@thphys.irb.hr weak decays of beauty mesons and baryons are believed to be a nice playground where a variety of phenomena should be well described and understood in the framework of the operator product expansion (ope) and heavy quark effective theory (hqet) [ , ]. the essential underlying idea in both theories is the expansion in inverse powers of heavy-quark mass – the mass of the beauty quark, mb ∼ o( gev ), is considered to be heavy compared with the typical hadron scale of . − gev . this is to be compared with the case of charmed mesons and baryons, where the mass of the charmed quark, mc ∼ . gev , is hardly an ideal expansion parameter. the rate of the beauty-hadron decay is given by Γ(hb → f ) = g fm b π |v | mhb {cf 〈hb|o |hb〉 + cf 〈hb|o |hb〉 m b + ∑ i c f 〈hb|oi |hb〉 m b + o( /m b) + ...} , ( ) where c f j are the wilson coefficients and md− b 〈hb|od|hb〉 ( ) are matrix elements of the d-dimensional operators which appear in the ope multiplied by the appropriate power of inverse quark mass. the sum in ( ) starts with d = , i.e. with o = bb giving mhb 〈hb|o |hb〉 = + o( /m b ) . ( ) clearly, in the asymptotic limit mb → ∞, one recovers the parton model result – as long as mb is large enough, one expects all corrections to stay moderate. furthermore, it is obvious from ( ) that there are no /mb corrections – a consequence of the nonexistence of independent operators of dimension four. the experimental situation is as follows: the lifetimes of beauty hadrons follow the simple theoretical mb → ∞ prediction within − %: τ (b+) = τ (b d ) = τ (b s ) = τ (Λb) , ( ) except for the lifetime of Λb, which appears to be by − % smaller than predicted in ( ). more precisely [ ], τ (b+) τ (b d ) = . ± . , ( ) τ (Λb) τ (b d ) = . ± . . ( ) the lifetimes of b hadrons are τ (b d ) = ( . ± . ) ps , τ (b+) = ( . ± . ) ps , τ (Ξb mixture) = ( . + . − . ) ps τ (Λb) = ( . ± . ) ps . ( ) theoretical estimates [ ] predict the ratio ( ) to be + . (fb/ mev ) , in accordance with experiment, but the ratio ( ) is predicted to be in the range τ (Λb) τ (b d ) ∼ . − . , ( ) which seems to be an overestimate. it appears, however, that the ratio τ (Λb)/τ (b d ) is not easy to lower down to the experimental value, the reason being that the /mb expansion converges rapidly. for example, keeping only operators with d = and d = , one obtains . for the ratio ( ). thus it seems difficult to accommodate this ratio with the same mass mb entering the decay rates of both Λb and b d. in fact, strangely enough, putting the physical hadron masses instead of mb would give τ (Λb)/τ (b d ) = . , up to the o( /m b ), in good agreement with experiment. however, this nice ansatz, proposed in [ ] completely spoils the ope and contradicts other ope predictions confirmed by experiments. therefore, the only hope to obtain the ratio ( ) in the framework of the ope and hqet is to look for the possible larger contributions coming from the operators with dimension d = or higher. these operators are known to play an important role in charmed-meson decays, in which, owing to the pauli interference effect [ , , ], there is a dilation of the lifetime of the d+ meson. in charmed-baryon decays, their role is even more pronounced: they give the dominant contribution leading to the well-established lifetime hierarchy which was successfully predicted prior to experiment [ , ]. unfortunately, the calculation of the matrix elements of the operators with dimension d = requires the use of quark models and is, therefore, strongly model dependent. recently, voloshin [ ] proposed the way to avoid the use of phenomenological models. he showed that using su( ) symmetry and hqet it was possible to relate the measured lifetimes of charmed hyperons to the differences in semileptonic decay rates, the differences in the cabibbo suppressed decay rates of charmed hyperons and the splitting of the total decay rates of b hyperons, without invoking the quark model results for the matrix elements [ , ]. he confirmed the predicted difference in the semileptonic decay rates between the Ξc and Λc by a factor to , and the enhancement of the semileptonic branching ratio for Λ+c coming from the cabibbo suppressed decay rate. when applied to beauty decays, voloshin’s approach leads to a difference of % in the lifetime of Ξ−b with respect to the lifetime of Λb. in this paper we extend voloshin’s analysis introducing a rather moderate model dependence, in order to obtain more predictive power, e.g. the values for the lifetimes of the (Λb, Ξb) hyperon triplet and the lifetime of Ωb. basically, we express the decay rates in terms of the nonrelativistic (nr) wave function at the origin Ψ( ), the value of which we determine using voloshin’s method. our starting point is the expression ( ). it is argued [ ] that the beauty mass which enters the expression ( ) is a running mass mb(µ). in the limit µ → , one obtains the pole mass which is very often used in calculations. it would be perfectly legitimate to use the pole mass in pure perturbative theory (with no nonperturbative contribution). however, the use of the pole mass is very problematic when nonperturbative corrections are calculated, because of the renormalon singularities resulting in an irreducibile uncertainty of o(Λqcd/mb) that is larger than the nonperturbative corrections we are calculating. shielding mb(µ) against renormalon ambiguities by choosing µ > . gev , one avoids problems with the pole mass. in fact, a natural choice for the scale µ is mb/ ∼ gev , as argued in [ ]. such a relatively low scale makes the ms mass inadequate for treating the decays. a natural definition of the running mass would be that with the linear dependence on µ: d m(µ) d µ = −cm αs(µ) π + ... . ( ) the recent value for mb(µ) at µ ∼ gev and for cm = / is given by [ , ] mb(µ = gev ) = ( . ± . ) gev , ( ) which is slightly lower than the usual values. in this calculation we use mb(µ = gev ) in the range . gev < mb( gev ) < . gev . next, we turn to the calculation of the matrix elements of the oi (four-quark) operators. we follow the approach given by voloshin [ ] based on hqet and flavor su( ) symmetry. a suitable parameter to express these matrix elements is the effective decay constant f ef f b which is an analogue of the static decay constant used to evaluate four-quark matrix elements in decays of heavy baryons [ , , ]. we use the following two differences of decay rates: for ∆ b = Γ(Λb) − Γ(Ξ b ), we have ∆ b = g f m b π | vcb | (c − s )( √ − z − ( − z) ( + z))[c (mb)x + c (mb)y], ( ) where z = m c /m b and c and s stand for cos θc and sin θc, respectively (θc is the cabibbo angle). for ∆ b = Γ(Ξ − b ) − Γ(Λb), we have ∆ b = g f m b π | vcb | [l x + l y], ( ) where l and l are the abbreviations for the following expressions: l = ( − z) c (mb) − [c √ − z + s ( − z) ( + z)]c (mb), ( ) l = ( − z) c (mb) − [c √ − z + s ( − z) ( + z)]c (mb). ( ) in the equations displayed above, ci stand for special combinations of wilson coefficients described in [ ], while x and y denote combinations of heavy-baryon matrix elements introduced first in the same reference: x = 〈 (bΓµb)[(uΓµu) − (sΓµs)] 〉 Ξ − b −Λb = 〈 (bΓµb)[(sΓµs) − (dΓµd)] 〉 Λb−Ξ b , ( ) y = 〈 (biΓµbj )[(ujΓµu i) − (sj Γµsi)] 〉 Ξ − b −Λb = 〈 (biΓµbj )[(sj Γµs i) − (djΓµdi)] 〉 Λb−Ξ b , ( ) similar relations are valid (through hqet and su( ) symmetry) for the respective members of the charmed hyperon triplet [ ]. the procedure of extraction of the effective parameter f ef f b is based on equating expressions obtained in two approaches. in the first approach, for the matrix elements x and y we use the su( ) hypothesis which basically comprises using values of matrix elements extracted from exper- imental data on charmed baryons for calculations in the beauty-baryon sector. this approach is based on the assumptions of su( ) and heavy-quark symmetry. in the second approach, x and y are calculated using the nonrelativistic quark model, already frequently employed for similar calculations [ , , ]. within this model, for x and y we have x = −y = − | ΨΛb ( ) | ( ) equation ( ) clearly shows that the valence approximation is used in the calculation of the matrix elements. the connection between the wave function squared, | ΨΛb ( ) | , and f ef fb is given by the relation [ , ] | ΨΛb ( ) | = t (f ef fb ) , ( ) where t = m(Σ b ) − m(Λ b ) m (b∗) − m (b) m ∗ u( m(b)κ(µ)− ). ( ) here µ ∼ gev is a typical hadronic scale of hybrid renormalization κ. the decay rate differences obtained in the first and in the second approach are denoted by ∆ib,su ( ) and ∆ i b,model, respectively (i = , ). the effective parameter f ef f b,i is now extracted from the equation ∆ib,su ( ) = ∆ i b,model. ( ) the expressions obtained for fbef f,i, i = , , are f ef f b, = √√√√ c (mb)x + c (mb)y t (c (mb) − c (mb)) , ( ) f ef f b, = √ l x + l y t (l − l ) . ( ) the final numerical value is calculated taking into consideration the errors of the expressions ( ) and ( ) and combining all numerical values appropriately. for mc = . gev and mb = . gev , we obtain f ef f b = ( . ± . ) gev . ( ) the parameter f ef f b shows a slight mass dependence which was incorporated in numerical calcu- lations. next, the numerical value displayed in ( ) is used in ( ) to obtain the values of the oi matrix elements. as all the matrix elements in the expression ( ) for the decay rate are now available, we can calculate the lifetimes of beauty baryons accordingly. the lifetimes of b mesons are calculated in a ”standard” way using the b-meson decay constant fb. since absolute results for lifetimes are not so reliable owing to ambiguities in quark mass, we shall express our results mainly in the form of lifetime ratios. our results for the ratio rΛb = τ (Λb)/τ (b d) are shown in fig. . the wilson coefficients in ( ) have been calculated at one loop using Λqcd = mev . other relevant numerical parameters used throughout the paper are [ , ] µ π = . gev , µ g(Ωb) = . gev , µ g(Λb, Ξb) = . the effect of introducing f ef f b , which we have calculated, is to bring the ratio rΛb from . to . – still two standard deviations from experiment. it is clear from fig. that variation in mb has almost no effect. also, the variation of µ π does change rΛb at the permile level. if the experimental ratio ( ) persists, then there might be the problem in b decays. an interesting effect in this approach noticed by voloshin is the enhancement of the lifetime of Ξ−b compared with the lifetime of Λb. using the ”standard” b-meson decay constant fb ∼ . . . . . mb (gev) . . . . . . . . . τ( Λ b) /τ (b d) mc = . gev mc = . gev mc = . gev figure : the shaded area represents the experimental value of the ratio rΛb within one standard deviation. the line with diamonds represents the calculated value of rΛb for the ”standard” value fb = mev . the values of rΛb using f ef f b are calculated for three different values of mass mc and are represented by lines without symbols. the significant shift from the ”standard” value result is visible, but the deviation from the experimental band is still substantial. mev , instead of f ef f b , one obtains for the ratio τ (Ξ − b )/τ (Λb) ∼ . . our calculation gives, fig. , τ (Ξ−b ) τ (Λb) ' . , ( ) i.e. a relative enhancement of the τ (Ξ−b )/τ (Λb) ratio of the order %, which is in fair agreement with the preliminary experimental results ( ) [ ]. the main reason for this enhancement is the large (positive) exchange contribution to Γ(Λb) versus the large negative pauli interference contribution in Γ(Ξ−b ). such an enhancement is even more pronounced in the lifetime of Ωb, giving the ratio τ (Ωb) τ (Λb) ' . , ( ) i.e. a relative enhancement of the ratio τ (Ωb)/τ (Λb) of the order %, fig. . this result is a . . . . . mb (gev) . . . . . . . τ( Ξ b− )/ τ( Λ b) mc = . gev mc = . gev mc = . gev figure : the line with diamonds represents the value of the ratio τ (Ξ−b )/τ (Λb) for the value fb = mev . values of the same ratio calculated using f ef f b are given for three mc masses and are represented by lines without symbols. the difference of ∼ % is clearly visible. consequence of the even stronger (compared with Ξ−b ) negative pauli interference contribution in Γ(Ωb). the results ( ) and ( ) should both serve as crucial predictions to be checked in experiment. the calculation gives τ (Ξ b ) approximately the same as τ (Λb), which together with ( ) and ( ) leads to the following lifetime hierarchy: τ (Λb) ' τ (Ξ b ) < τ (Ξ−b ) < τ (Ωb) . ( ) as long as the absolute value of the Λb lifetime is concerned, the effect of f ef f b is to lower the theoretical value of τ (Λb) by ∼ %, giving τ (Λb) ∼ . ps , ( ) which is too high compared with the measured value ( . ± . ) ps. to obtain better agreement with experiment, one needs larger mb. if, for example, we use the pole masses m pole b = . gev , mpolec = . gev , the result is τ (Λb) pole = . ps – still too high vis-à-vis experiment. however, . . . . . mb (gev) . . . . . . . . . τ( Ω b) /τ (Λ b) mc = . gev mc = . gev mc = . gev figure : the value of the ratio τ (Ωb)/τ (Λb) obtained using fb = mev is represented by the line with diamonds. values of the same ratio for f ef f b , represented by lines without symbols, are calculated for three different mc masses. calculations using fb and f ef f b differ by ∼ %. playing with a large pole mass is merely an introduction of an additional parameter – a consistent treatment requires having the running mass mb(µ) in the expansion and its value could hardly reach more than . gev . much the same situation appears in the calculation of b-meson lifetimes, which is not affected by our approach. typically, one obtains τ (b) ∼ − . ps for mb = . gev and τ (b) ∼ . − . ps for mb = . gev , the range of values for τ s coming from the variation of mc, . gev < mc < . gev . comparing with the results for the calculated value of τ (Λb), one sees that it is easier to have τ (b d ) near to the experimental value. this may suggest that the problem with too large a theoretical value of rΛb lies in the theoretical overestimate of τ (Λb). to conclude, we point out the following. the calculations presented in this paper rely upon hqet and flavor su( ) symmetry and are therefore reliable up to violations of these symmetries. still, we expect the effects of these violations to be smaller than the main effect of our approach. the procedure applied above significantly increases the contribution of four-quark operators and numerical results show a significant, albeit still unsufficient shift towards experimental values, especially in the case of the rΛb ratio. in our approach, to reach the experimental value of rΛb, would require f ef f b to have the value . gev , which can be hardly achieved. the discrepancy, still remaining after increasing the preasymptotic effects coming from four-quark operators, indicates that there should be other, yet unknown, sources of enhancement of preasymptotic effects and that these effects should also produce significant contributions. also, there remains the possibility of violation of some of the underlying concepts, such as quark-hadron duality, but a consistent treatment of these problems is still out of the reach of the present theory. in our approach, the large contributions of the operators of d = also suggest a much wider spread of lifetimes in the sector of beauty baryons. the extent of this spread is to be verified by future experiments. at the end, we state that a systematic application of the ope, hqet and a moderately model-dependent procedure of enhancement of preasymptotic effects improves the rΛb ratio significantly, although it cannot resolve the problem completely. we consider this problem along with the problem of absolute lifetimes of beauty hadrons to be one of the most important issues that heavy-quark physics should address in the future. acknowledgements this work was supported by the ministry of science and technology of the republic of croatia under the contract nr. . references [ ] m. neubert, ”b decays and the heavy-quark expansion”, preprint cern-th/ - and hep-ph/ , to appear in ”heavy flavors ii”, eds. a.j. buras and m. lindner. 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[ ] j.l. cortes, j. sanchez guillen, phys. rev. d ( ) . none bjpsych international volume number august to link clinical neuropsychiatry with quantitative neuro biology. this does not mean that drugs are the only answer to treatment. targeted psycho logical treatments such as cognitive–behavioural therapy can use the brain’s capacity for neuro plasticity to remedy or restore communications within neurocircuits in some psychiatric condi tions. insel, t. r. & bruce, n. c. ( ) brain disorders? precisely. science, , . doi: . /science.aab brain grey matter and blood groups we know of some drugs such as lithium increasing brain grey matter but did you know that our own blood group, abo type, has a major role to play? there is evidence that people with blood group ab have a higher incidence of cognitive deficits. this led researchers to examine possible differences in grey matter volumes between people with blood group o and those with other blood groups; none of the participants had cognitive impairment or neurodegeneration. they found that those with blood group o had larger volumes of grey matter in the posterior ventral portion of the cerebellum (areas responsible for sensori motor information) as well as in the temporal and limbic regions, including the left hippocampus. these findings point to a neuroprotective role for the blood group o alleles and suggest that blood group types are relevant to the development of the nervous system as well as the ageing process. de marco, m. & vepperi, a. ( ) ‘o’ blood type is associated with larger grey-matter volumes in the cerebellum. brain research bulletin, , – . doi: . /j.brainresbull. . . mental illness and creativity – is there a link? the connections between creativity and mental illness were made as far back as ancient greece and aristotle, and it has fascinated people for centuries. the authors of this study tried to examine this possible connection using scientific methods. they investigated whether common genetic variants that affect risk for schizophrenia and bipolar disorder also underlie advantageous cognitive traits. they used polygenic scores or cumu lative genetic profiles from across the genome and generated separate polygenic risk scores for schizo phrenia and bipolar disorder on non icelandic populations. they then tested the ability of polygenic scores to predict the corresponding disease in people in iceland and looked for an association between these polygenic scores and creativity. creativity was defined as individuals belonging to national artistic societies of actors, dancers, musicians, visual artists and writers. both the schizophrenia and bipolar disorder polygenic risk scores were associated with creativity. the authors conclude that creativity may increase the risk of psychiatric disorder. nevertheless, in the absence of other important pathogenic factors it is unlikely that our talented artists or writers will experience mental illness. power, r. a., et al ( ) polygenic scores for schizophrenia and bipolar disorder predict creativity. nature neuroscience (online). doi: . /nn. stranded and drowned in the mediterranean – who cares? almost daily we hear of boats full of people capsizing on the way to europe. italy and greece are constantly on the alert, fishing out desperate people from overcrowded boats reach ing their waters. about people are thought to have perished in the mediterranean between january and may . the survivors face an uncertain future. european citizens are facing the biggest test of their humanity and sense of respon sibility to the rest of the world. many european countries need to reflect on their colonial past and more recent involvement in africa and the middle east and ponder over how they became so affluent and powerful. with power comes responsibility. unfortunately, globalisation has failed to decrease the gap between the rich and the poor in the world. it seems to serve the economic interests of the powerful, with no real benefit to those who are weak. is this a matter for doctors to consider? pandora welcomes readers’ views. a beautiful mind it is with great sadness that pandora reports the death of the famous mathematician john forbes nash. his remarkable research has been applied to a number of important areas, including macro economics, arms control and political science. he shared the nobel prize in economics in and was on his way from a ceremony in oslo, where he had been awarded the abel prize, accom panied by his wife, alicia de larde nash, when their taxi crashed, killing them both, on may. john nash became more widely known by the film a beautiful mind, which was based on his life and which portrayed him battling with delusions and hallucinations. however, psychiatric treatment enabled him to continue his highcalibre work despite his illness (schizophrenia). his life shows both doctors and patients that mental illness, even one as serious as schizophrenia, can be controlled (he was treated with powerful anti psychotic drugs) and its presence should not be an end to one’s aspirations. bjpsych international’s blog http://www.bjpinternationalblog.org now features: reflection on mrcpsych examination in the uk viviane ngwompo there is no mental health without caregivers jens peter dam eckardt jensen child psychiatry in iran hadi shaker naeeni absence of humanities in china’s training of psychiatrists jie li, maosheng ran and cecilia lai-wan chan my first private outpatients in india – the experience of a psychiatrist trained in the uk sundararajan rajagopal opportunities to improve prison mental healthcare annie bartlett and gillian mcgauley downloaded from https://www.cambridge.org/core. apr at : : , subject to the cambridge core terms of use. https://www.cambridge.org/core bjpsych international volume number august volume number august bjpsych international (print) issn - bjpsych international (online) issn - subscriptions bjpsych international is published four times a year. for subscriptions non-members of the college should contact: publications subscriptions department, maney publishing, suite c, joseph’s well, hanover walk, leeds ls ab, uk tel. + ( ) ; fax + ( ) ; email subscriptions@maney.co.uk for subscriptions in north america please contact: maney publishing north america, massachusetts avenue, th floor, cambridge, ma , usa tel. 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are encouraged to contribute online at http://www.bjpsychinternationalblog.org editor david skuse deputy editor george ikkos founding editor hamid ghodse staff jonica thomas andrew morris (head of publications) editorial board senior editorial advisors rachel jenkins uk john cox uk associate editors michel botbol (europe) france nick bouras (special papers) uk santosh chaturvedi (indian subcontinent) india manu dhadhpale (country profiles) india david jimenez (media and south america) uk kelly lai (south-east asia) hong kong nasser loza (middle east) egypt daniel maughan (sustainability) uk olufemi olugbile (africa) nigeria eleni palazidou (pandora’s box) uk dr ian soosay (oceania) new zealand other members katy briffa uk jorge calderon chile rakesh chadda india george christodoulou greece anna datta new zealand oluwole famuyiwa uk stephen kisely australia marinos kyriakopoulos uk gholam reza mir-sepassi iran hellme najim uk david ndetei kenya sean o’domhnaill ireland sundararajan rajagopal india mohamed omar salem uae samuel stein uk mission of bjpsych international we address themes that have real practical relevance to supporting patients, with a particular, but not exclusive, focus on the needs of low- and middle-income countries as well as the mental health needs of the poor and socially excluded in more developed countries. contributors who can provide examples of innovative practice, which could be emulated elsewhere at minimal cost, are especially welcome, as are papers on public mental health. open access online access to bjpsych international is unrestricted; use of its content is governed by an open access licence agreement. blog http://www.bjpsychinternationalblog.org facebook https://www.facebook.com/bjpsychinternational twitter @ bjpsychint forthcoming international events – september international association for child & adolescent psychiatry and allied professions world congress calgary, canada website http://www.iacapap .org/ the international association for child and adolescent psychiatry and allied professions (iacapap) hosts its world congress every two years. the mission of the congress is to bring together children’s mental health professionals to exchange and present scientific research and information for the betterment of child and adolescent mental health globally, nationally and regionally. in addition, the canadian academy of child and adolescent psychiatry will hold its th annual conference jointly with iacapap . the theme of the congress is ‘fighting stigma, promoting resiliency and positive mental health’. – november world psychiatric association international congress cape town, south africa website http://www.wpacapetown .org.za the congress theme, ‘psychiatry: integrative care for the community’, is intended to explore concepts, controversies and consequences of psychiatry’s responsibility and accountability to society in terms of the scope of practice and of what can be considered as psychiatry’s social contract. the key concepts will be: integration (how to integrate the developing scope of current psychiatric practice); environment (the more important questions on medicine and the medical profession being posed now, in the early st century, are about the best ways for doctors to contribute in a world which is changing exponentially); the scope of psychiatric practice; social contract (the series of reciprocal rights and duties, privileges and obligations); multiple stakeholders. bjpsych international volume research supplement, may the research supplement is freely available online at http://www.rcpsych.ac.uk/publications/journals/ipinfo . aspx. it feature the following papers: development of a psychiatric liaison service in rawalpindi, pakistan ayesha minhas, keith g. bender and fareed a. minhas the effect of aerobic exercise in the maintenance treatment of depression p. majumder, i. sharma, p. vostanis and c. bone scaling up mental healthcare in the republic of niger: priorities for and barriers to service improvement alison hwong, djibo maiga douma, soumana zamo and julian eaton evaluation of undergraduate psychiatry teaching in malawi amy e. lindsay and stephen byers hospital doctors’ management of psychological problems at a nigerian tertiary health institution baba a. issa, abdullahi d. yussuf, olatunji a. abiodun and ganiyu t. olanrewaju mental health e-supervision for primary care doctors in sudan using the who mhgap intervention guide anne aboaja, puja myles and peter hughes the who mhgap intervention guide for people with intellectual disability: the sri lankan experience rohit gumber, shweta gangavati, sabyasachi bhaumik, sherva cooray, kiran purandare, jayan mendis and chamila abeywickrema acceptability and challenges of implementing the nice guidelines for schizophrenia in lagos, nigeria adeniran okewole, mobolaji dada, adefemi adeoye, kehinde lawal and taiwo oduguwa mental health research in the arab world: an update elie g. karam and lynn a. itani downloaded from https://www.cambridge.org/core. apr at : : , subject to the cambridge core terms of use. https://www.cambridge.org/core ced .indd case reports references fisher cm: pure sensory stroke and allied conditions. stroke ; : – . kim js, bae yh: pure or predominant sensory stroke due to brainstem lesion. stroke ; : – . bogousslavsky j, maeder p, regli f, meuli r: pure midbrain infarction: clinical syndromes, mri, and etiologic patterns. neurology ; : – . kumral e, bayulkem g, akyol a, yunten n, sirin h, sagduyu a: mesen- cephalic and associated posterior circulation infarcts. stroke ; : – . kim js, kim j: pure midbrain infarction. clinical, radiologic and patho- physiologic fi ndings. neurology ; : – . ono s, inoue k: cheiro-oral syndrome following midbrain haemorrhage. j neurol ; : – . azouvi p, tougeron a, hussonois c, schouman-claeys e, bussel b, held jp: pure sensory stroke due to midbrain haemorrhage limited to the spi- nothalamic pathway. j neurol neurosurg psychiatry ; : – . konstantinos spengos, md vas. sofi as gr– athens (greece) tel. + , fax + e-mail spengos@hol.gr discussion to our knowledge, no case of isolated dorsal midbrain infarc- tion has been reported previously. the investigators of the laus- anne [ ] and the ege stroke registry [ ] described and patients with infarct limited to the mesencephalon respectively. more re- cently, the clinical, radiological and pathophysiological fi ndings of patients with pure midbrain infarction were reported [ ] . how- ever, the authors did not observe any subject with lesion restricted to the dorsal midbrain. this territory is supplied by different arter- ies arising from the collicular artery, which gives rise to a network of small arteries also supplied by branches of the posterior cerebral artery. sometimes the superior cerebellar artery also participates in the supply of the inferior colliculus. furthermore, the same authors indicated that according to their experience, infarcts in this area were invariably associated with the concomitant involvement of the cerebellum [ ] . in our case, the clinical features were characterised by sensory defi cits caused by the involvement of the dorsolaterally located lem- niscal and spinothalamic sensory fi bres ( fi g. ). although the infarct affected the superior colliculus and the periaqueductal grey matter unilaterally as demonstrated on mri, these lesions did not corre- spond to any clinically overt neurological defi cit. pure sensory stroke is most frequently associated with thalamic lacunes [ ] , or occasionally with lesions located in the lateral pontine tegmentum, involving the medial lemniscus and the lateral spinothalamic tracts in the rostral pons [ ] . two cases of lateral tegmental midbrain haemorrhages limited to the spinothalamic pathways have been described as extremely rare causes of pure sensory stroke [ , ] . in addition, kim and kim [ ] identifi ed patients with ischaemic le- sions restricted to the lateral midbrain presenting with isolated sen- sory symptoms. small vessel disease was the pathogenic mechanism of infarction in case, while atherothrombotic large vessel disease was categorized as the pathogenic aetiology in the other. in the ab- sence of any evidence of stenosis or occlusion of the large vessels and of any emboligenic heart disease, we considered small vessel disease as the most plausible cause of stroke in our patient. in conclusion, the present report highlights the diversity of the topography of the underlying ischaemic lesions in patients present- ing with pure sensory stroke. therefore, although its incidence is extremely low, isolated posterior midbrain infarction should be considered as an infrequent cause of pure sensory stroke. fig. . axial schematic diagram of midbrain depicting the ana- tomical structures and the different locations (a, anteromedial, b, anterolateral, c, lateral, d, dorsal) of midbrain infarctions. beauty parlor stroke syndrome j.g. heckmann a , p. heron a , b. kasper a , a. dörfl er b , c. maihöfner a departments of a neurology and b neuroradiology, stroke unit, university of erlangen-nuremberg, erlangen , germany a -year-old woman visited her beauty parlor to have her hair cut. during shampooing with her head hanging backwards into a hair washbasin she developed sudden dizziness, nausea and started vomiting. the alarmed paramedics assumed a gastrointestinal dis- order, and she was initially admitted to the department of gastro- enterology. as symptoms persisted for days, neurological advice was sought. the neurological examination revealed nystagmus at forced lateral view bilaterally, slight left-sided ataxia of both limbs and she was prone to fall to the left side in the romberg test. the vascular risk factors were suffi ciently treated diabetes type ii and arterial hypertension. in our routine stroke workup which is based on the eusi guidelines [ ] , no further pathological fi ndings were detected, in particular no signs of cardioembolism. mri of the brain showed an ischemic infarction in the territory of the left pos- terior inferior cerebellar artery ( fi g. a). mr angiography ( fi g. b) showed a smaller lumen of the left vertebral artery compared to the right but without signs of arterial dissection or major arterioscle- rosis. in our patient we diagnosed beauty parlor stroke syndrome, a term proposed by weintraub in [ ] . pathophysiologically, acute arterial dissection is considered to be a major cause [ , ] . in these cases, patients often reported about pain in the neck and a cerebrovasc dis ; : – doi: . / case reports predisposing intimal-medial weakness has been assumed [ ] . oth- er predisposing vascular factors discussed for this stroke entity are atherosclerosis, impaired collateral blood fl ow and presence of con- genital vascular hypoplasia. however, also speed, applied force and duration of the hair washing defi nitely contribute [ , ] . in our case dissection could confi dently be excluded by mr angiography and conventional mr sequences. an arterio-arterial embolism, occur- ring by shearing of an athersclerotic plaque of the vertebral arteries during hyperextension, seems unlikely due to missing signs of pro- nounced arteriosclerosis in mr angiography and additional neuro- sonological examinations. cardiac embolism was unlikely due to normal ecg and transesophageal echocardiography. therefore, we assume a disturbed end organ perfusion mecha- nism affecting the territory of the left posterior inferior cerebellar artery as the pathophysiological cause, for which the slight left-sided vertebral artery hypoplasia may have been predisposing. the inter- ruption of the blood fl ow is thought to be caused by mechanical compression of the vertebral artery between the occiput and the ver- tebral arc of the atlas during the prolonged hyperextension ( fi g. ). this concept is supported by cerebral blood fl ow studies in symptomatic individuals which demonstrated abnormal fi ndings during hyperextension and rotation of the neck and head and un- suspected hypoplastic vertebral artery in % [ ] . thus, it can be speculated that hypoplasia may play a predisposing role, in par- ticular if the vertebral artery with the larger calibre is compromised by the tilting of the neck during barbering. taken together, hyperextension combined with hanging the head backwards in a hair washbasin can be seen as a risk factor for posterior circulation ischemia. it probably occurs more often than assumed [ ] and a number of patients may report about previous dizziness episodes under the same conditions when asked specifi - cally [ ] . it can be prevented by changing the shampoo routine from the hanging head position to a fl exed or neutral position [ ] . age can be regarded as a potentially predisposing factor, as our patient and nearly all the patients whose cases were reported in the litera- ture are years and older [ , ] . the european stroke initiative executive committee and the eusi writ- ing committee: european stroke initiative recommendations for stroke management – update . cerebrovasc dis ; : – . weintraub mi: beauty parlor stroke syndrome: report of fi ve cases. jama ; : – . nwokolo n, batemen de: stroke after visit to the hairdresser. lancet ; : . agarwal r, shukla r, chandra a, pant mc: posterior circulation stroke following manipulation of neck by a barber. j assoc physicians india ; : – . weintraub mi: stroke after visit to the hairdresser. lancet ; : – . jeret js, bluth m: stroke following chiropractic manipulation: report of cases and review of the literature. cerebrovasc dis ; : – . weintraub mi, khoury a: critical neck positions as an independent risk factor for posterior circulation stroke: a magnetic resonance angiographic analysis. j neuroimaging ; : – . shimura h, yuzawa k, nozue m: stroke after visit to the hairdresser. lancet ; : . foye pm, najar mp, camme a, et al: pain, dizziness, and central nervous system blood fl ow in cervical extension: vascular correlations to beauty parlor stroke syndrome and salon sink radiculopathy. am j phys med rehabil ; : – . references dr. josef g. heckmann department of neurology, university of erlangen-nuremberg schwabachanlage , de– erlangen (germany) tel. + , fax + e-mail josef.heckmann@neuro.imed.uni-erlangen.de fig. . a diffusion-weighted mri demonstrating an ischemic in- farction in the territory of the left posterior inferior cerebellar ar- tery. b mr angiography showed normal posterior circulation ves- sels except for a slight hypoplasia of the left vertebral artery. fig. . schematic drawing of the proposed pathomechanism. through hyperextension of the neck and head, the vertebral artery (arrow) is compressed between the occiput and the vertebral arc of the atlas in susceptible individuals. untitled- © nature publishing group nature [november , most complete and authoritative existing. messrs. king and thompson have also taken some unique photographs of the monument. in the sudan, dr. budge, of the british museum, and mr. j. w. crowfoot, inspector of education in the sudan, have completed the work which the former began at meroe in . they finally cleared out the shrine of the largest pyramid, and made some in- teresting explorations in the country near the second cataract. dr. budge, whose services had been pre- viously lent to the sudan government by the british museum in , , and , is now engaged on an account of his four missions to that country, which is announced to appear in the spring. we cannot close this account of british arch<:eo- ological work without a word of con- gratulation to our american friends on the success of the excavations of mr. theodore n. davis, assisted by mr. j. e. quibell, the british inspector of antiquities in upper egypt, in the valley of the tombs of the kings at thebes. mr. davis found the un- touched tomb of iuaa and tuaa, the father and mother of the great queen tyi, consort of amenhetep iii. and mother of the heretic king akhunaten. the tomb was full of the most magni- ficent furniture, chariots, &c., mostly thickly overlaid with gold. mr. davis will proceed with his excavations this winter with the assistance of mr. ayrton, who has left the egypt exploration fund for this purpose. the beauty of minute structure in nature. prominence to curiosities and out-of-the-way objects, we are here brought into close quarters with the familiar, with diatoms and foraminifera, the whelk's radula and the barnacle's cirri, the butterfly's " tongue " and the scales of the sole, the spine of the sea-urchin and the spider's foot, a gnat and a house- fly's eggs, the dodder entering the clover, the bud of the lily flower, the sting of the nettle and the stem of wheat, and so on through a long list. along with each of the sixty-five illustrations there is a short and clear description, and a note of the conditions of the photograph, e.g. magnification, focal distance, and exposure. the photographs were taken bv mr. arthur e. smith, and are certainly among the finest that have ever been published. they were taken. for o ne of the many "ways of beginning the study of natural science is with a " beauty-feast "-of flowers or birds, of shells or gems, of anything- for all natural things are beautiful, in their proper setting at least. it is an old-fashioned mode of approach, com- mending itself to children and simple minds, but one which often leads far beyond <:esthetic pleasure to the joy of understanding. it affords a dynamic to investigation, and fosters a healthy reverence for things. in school " nature- study " the <:esthetic factor should be characteristic, though it is too often con- spicuous by its absence. indeed, if we had to choose, we should prefer admir- ation without science to science without "admiration. but a simple book like that before us shows that there is no neces- fig. i.-diatom, frojil bori, hungary, x tooo. from" nature through microscope and camera." sary antithesis; it is a disclosure of beautiful things, and yet within its limits it is quite scientific. the author's aim is to illustrate by well chosen examples the beauty of minute structure, the beauty which the microscope discloses, and he is to be con- gratulated on his success. while older books on " the wonders of the microscope " had to be content with drawings, some of which were exquisitely done, this book presents us with photomicrographs of the highest excellence. it is difficult to over-praise them. moreover, while the older books gave too much ''nature through microscope and camera.'' by·richard kerr; with photomicrogr: phs by arthur e. smith. pp. i · (london: religious tract society, rgos.) price s. net. no. , vol. ] the most part, on by ro plates, and have been somewhat reduced in the process blocks. mr. smith contributes a useful chapter of practical hints on photomicrography. mr. kerr is an enthusiastic photographer, who believes in his " intellectual pastime " as helping, in- directly, to 'remedy some of the ills we are heir to, such as " the amusement fetich." but he is more he is a student of the beautiful things · which delights in, and he can tell their story in a plain straightforward way. the moral that adorns his is expounded by prof. g. sims woodhead in a finely conceived introduction; but we shall only say this, that the whole spirit of this beautiful book is well © nature publishing group november . ] nature los expressed in the prefatory quotation from sir j. f. w. herschel:-" to the natural philosopher there is no natural object that is unimportant or trifling; from the least of nature's works he may learn the greatest lessons." j. a. t. the wastage in araiies by disease. ' j' he recent utterances of sir frederick treves on the subject of the army medical service (see nature, november , p. rs), and the discussion on enteric fever in the army which has appeared in the columns of the times, have again directed attention to the inadequacy of the means taken in our army to prevent the incidence of enteric fever and other filth diseases. the crux of the matter is this : we have to provide hospital accommodation for io per cent. of our forces in the field, the japanese for but per cent. why this difference? in the south african campaign no less than per rooo of the fighting forces were admitted into hospital for disease which is mainly preventable. in this war there were something like o,ooo admissions to hospital on account o-f sickness and some ,ooo admissions on account gi wounds or injuries received in action. " among those admitted to hospital on account of disease alone, there were , oo deaths during the whole war; further, so far as can be estimated at present, , of the total admissions to ho'spi'tal on account of 'disease, and of the deaths from disease, were due to enteric fever,· while r , of the admissions and i of the deaths. were from dysentery. in other words, no less than one-tenth of the admissions on account of disease were for enteric fever, and one-fourteenth were for dystentery, or these two diseases alone were 'the ·cause of practically one-sixth of the total admissions and about two-thirds of the total deaths on account of disease ; these two diseases also accounted for nearly one-half of . the total losses by death from all causes during the war. as we know that both enteric and dysentery belong to the group of diseases which are largely the outcome of faulty environment the sanitary significance of these figures needs no how does the japanese army deal with the preven- tion of disease? the following record sufficiently answers this question :- " the care of the sick and wounded occupied but a small share of the time of the medical officers. the solu- tion of the greater problem of preventipg disease by the careful supervision of the smallest details of subsistence clothing and shelter was their first and most important duty. nothing was tcio small to escape their vigilance, too to weary their patience, and everywhere, m the field wtth the scouts or in the base hospitals at home, the one prevailing idea was the prevention of disease. the medical officer was to be found both in the front and in the rear. he was with the first screen of scouts with his microscopes and chemicals, testing and labelling 'wells, so that the army which followed should drink no con- taminated water. when scouts reached a town he imme- made a. thorough of the sanitary condttwns, and jf caoes of contagwus or -infectious disease were found, he a cordon around the quarter where they were. a medtcal officer accompanied foraging parties and, the commissariat officers, sampled the food, frlllt, and vegetables sold by the natives before the arriva! of the. army. if the foo,d were tainted, or the fruit over-n pe, or jf the water required boiling, notices to that effect were posted in suitable places. so strict was the discipline from commanding officer to rank and file that obedience. to the orders of the medical officer was absolute. the medtcal officer also supervised the personal hygiene of the camp. he taught the men how to cook, how to bathe, how to cleanse the finger nails so as to free them as w:ll as how to live in general a healthy, vtgorous hfe, and t was a part of the soldier's routine t carry out these instructions in every particular. as a l lieut.·col. firth, r.a.m.c., journ. of hygiene, sept., •gas, p. · no. t . vol. ] result of this system the medical officer was not obliged to treat cases of dysentery and fevers that follow the use of improper food and the neglect of sanitation. during six months of terrible fighting and exposure in a foreign country there was only a fraction of per cent. of loss from preventable disease." it may be true that vehicles other than water, par- ticularly dust and flies, convey the infection in enteric fever, diarrhma, and dysentery, but much can be done by safeguarding the water supplies. diminish the incidence of these diseases by any means whatever and the subsequent incidence of the disease will naturally be lessened-cases beget cases. it may or may not be practicable to sterilise the drinking water for a big army in the field, but in camps and in small campaigns such as our " little wars " on the indian frontier, and in africa, a great deal more could be done than has been done. thus in the tochi valley, in r g , a force of some men was condemned to inactivity and suffered severc'y from diarrhma, dysentery, and enteric. the british troops averaged an annual strength of , and among them there were cases of enteric with deaths, cases of dysentery with deaths, and zu cases of diarrhoea with ro deaths. here was an ideal instance in which sterilisation of the water or distillation for the sick (as the water was verv saline) could have been carried out, as there was· plenty of fuel, and the extra cost involved would probably have been more than covered by the saving- in pensions, &c. lieut. nesfield, i.m.s., in the tibet campaign used hisiodide iodate tablets (see nature, july , p. , and august , p. ), with the result that of oo men who drank water sterilised with them, none con- tracted cholera, while of other batches of men passing through the same region a few days later an average of per cent. contracted cholera. there can be no question that the medical officers of otjr army are a devoted body of men, highly trained, and fully alive to what should be done, but· they are too few adequately to cope with the problem. of pre- vention, and what is more they receive little encour- ag'ement in this direction from those in authority. in addition, a body of intelligent trained non-commis- sioned officers and men, a sanitary corps, is required to carry out the policy of the medical officers. at present guards for the water supply and similar pur- poses are drawn from the ordinary strength of the regiments, with, of course, no special training. in the china relief expedition in rgoo the japanese provided three skilled men to take care of their sick and wounded for every two provided by the , other armies. in olden times it was thought cheaper to obtain a new soldier than to cure a sick or wounded one; the reverse is the case nowadays if the authorities would but appreciate it, and prevention is even better than cure. r. t. hewlett. notes. we announce with deep regret that sir j. s. burdon sanderson, bart., f.r.s., late regius professor of medicine in the university of oxford, died at oxford on november . prof. emil warburg, president of the reichsanstalt in charlottenburg, and prof. henri moissan, of the university of paris, have been elected corresponding members of the academy of sciences of munich. the twenty-first anniversary of geographical society was celebrated burgh on monday, november . president of the society, presided. the royal scottish by a dinner in edin- prof. j. geikie, the b "f. med. journ., , ii. p. . the beauty of minute structure in nature. beauty and fantasy in nairobi park beauty and fantasy in nairobi park beauty and fantasy in nairobi park by robin tomkinson if you have never seen the african animals except in zoos, and have always longed to see them wild, the nairobi national park is a sort of paradise. at first it is hard to believe that you are not in the middle of a wonderful dream, though as with many such dreams, there is grimness lurking in the background in the form of vultures, hyaenas, and, of course, lions. though the park is quite small, only about square miles, the number and variety of animals is amazing, especially con- sidering that during the war it was an army training ground, so hardly a peaceful place for them. but now, driving slowly along, you find hundreds of beautiful and fantastic beasts strolling unconcernedly around you, for they have found that they are safe from men in cars, if not from lions. the country is fairly flat, so from the entrance to the park there is a very good view and it is thrilling to see the game in large and small herds scattered all over the plains, and then to look through field-glasses and discover that among them are giraffe, zebra, wildebeest, impala, and all sorts of other exciting animals. when the car comes towards them they do not stampede as one might expect of such wild things, but simply get out of the way if they happen to be on the track or very near it. (the old wildebeest seem to like lying down in the fairway, and take a very low view of being disturbed !) even sitting in the car (which you may not leave), you can really appreciate the many different ways in which these animals are beautiful and interesting, and especially the charms of the antelope-gazelle family, who, as a rule, are so very nervous and wild. there is the incredible grace of their movements, which you cannot realize unless they are free, then the exquisite detail of their heads, ears, eyes, and horns, and also the lovely colour and texture of their coats. it is fascinating to watch the different kinds of movement. the gazelles are so light and airy that one can easily imagine them dancing to a rondo by mozart. i saw two. grant's gazelles playing, almost dancing ; they began by tearing round and round in circles then, as they grew still more intoxicated with their own movement they jumped into the air again and again, about feet clear of the ground, and this was simply joie de vivre as they were obviously not afraid. not all the animals are beautiful, but the infinite variety is so interesting—" why rushed the discords in, but that harmony should be prized ? " for instance the variations on the antelope- cambridge core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core oryx gazelle theme are fascinating; beginning with thomson's gazelle (tommies), all fire and air and lightness and grace, and ending with the wildebeest who looks like a nightmare. between such extremes are grant's gazelle, taller and less elf-like than the tommies, but the height of elegance, with most lovely horns and long pointed ears, exquisitely shaped. they know quite well that their appearance is beyond criticism. under the green fever trees by the athi river are herds of impala, a lovely bright chestnut on their necks and backs, paler on the flanks and white underneath. their big ears are lined with white and tipped with black velvet, and above their hind fetlocks are little black tufts which look like anklets. the old rams have magnificent horns with very beautiful and complicated curves. alas i did not see their wonderful jumping, when they become almost airborne. the waterbuck are different from most other antelopes, as their coats, instead of being smooth and shiny, are rather like a pony's in the winter, and the hair on their necks is quite thick and long. they too are beautifully " finished ", their fluffy rounded ears have black tips and white linings, and there is some reddish-brown at the base of their horns. we had a perfect view of one with a very fine head, standing half-hidden in the long dead grass about thirty yards from the track. we stopped the car and he stood absolutely still for about five minutes considering us. his head carriage and the curve of his horns were superb. two good examples of the not-so-beautiful of the antelope kind are the wildebeest and the kongani (or " konk "). the wildebeest, though a bit nightmarish, are quite decorative and look rather heraldic especially when they gambol and prance for no apparent reason ; they often go about with zebras, who in their striped way are almost equally fantastic. but the poor old konks are just plain ugly. they look as though they had tried to be picturesquely ugly like a wildebeest, failed dismally, and then made a despairing effort to turn into an elegant sort of antelope—failed again and ended by looking like nothing on earth ! to make things worse they seem rather apologetic about it all, and even the babies look solemn and elderly. although they are so fantastic the giraffes are some of the most decorative of all, and in the park you can see them per- fectly and appreciate their wonderfully graceful way of coping with such unorthodox necks and legs. they are sometimes called ungainly and from their extraordinary shape one would almost expect them to be, but when they have plenty of room to cambridge core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core beauty and fantasy in nairobi park manoeuvre they are a delight to watch ; they move as though every joint was perfectly oiled and glide along like a slow- motion film. when you see a procession of about ten of them walking in single file, with the black ends of their tails streaming in the wind, they look superb, and you realize what much longer tails they have than you had imagined. sometimes one of the nairobi giraffes will stand about yards from the car, watching you, so that you can see the lovely detail of his head and his great dark brown eyes, with lashes longer than any film star's. the general effect of a giraffe's head with the curved and pointed ears, the spots and the delicate lines is somehow rather like an exotic orchid. these are just some impressions of a rather ignorant enthusiast, and i have mentioned only a few of the animals, and none of the birds, which are also fascinating. but after seeing so many lovely things one felt more than ever how much national parks like the one at nairobi are needed. without such sanctuaries it would be only a matter of time before all or most of the game disappeared, as indeed it has in most areas which are not national parks or game reserves. this was very much impressed on me during two months' stay in kenya and uganda, in the course of which we travelled some , miles. most of the nairobi park animals drifted in from the adjoining masai reserve, which is one of the few remaining places in kenya which are still well stocked with game. they come and go as they like between the park and the reserve. the game wardens, mostly behind the scenes, must be doing a very fine job, which benefits not only the animals but the people who come to see and enjoy them. one can only hope they will get every encouragement to carry on the good work, so that there may still be some places where gazelle, impala, giraffe, and zebra and many others can continue to live and move, because they are really some of the loveliest things in this world—where loveliness grows rarer. cambridge core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/ . /s downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the https://www.cambridge.org/core/terms https://doi.org/ . /s https://www.cambridge.org/core ellison hb beauty: in the gonads of the beholder — and the beheld the harvard community has made this article openly available. please share how this access benefits you. your story matters citation ellison, peter t. . beauty: in the gonads of the beholder – and the beheld. hormones and behavior ( ): - . published version http://dx.doi.org/ . /j.yhbeh. . . citable link http://nrs.harvard.edu/urn- :hul.instrepos: terms of use this article was downloaded from harvard university’s dash repository, and is made available under the terms and conditions applicable to open access policy articles, as set forth at http:// nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of- use#oap http://osc.hul.harvard.edu/dash/open-access-feedback?handle=&title=beauty:% in% the% gonads% of% the% beholder% %e % % % and% the% beheld&community= / &collection= / &owningcollection / &harvardauthors= e adc dbccb a d f ddc &departmentanthropology http://nrs.harvard.edu/urn- :hul.instrepos: http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#oap http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#oap http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#oap beauty: in the gonads of the beholder – and the beheld i remember being puzzled as a teenager by some of the male sex symbols whose posters adorned girls’ dorm rooms. robert redford and paul newman i could understand, but humphrey bogart, with his weak chin and crooked smile? or french heart-throb jean-paul belmondo, with his big mouth and prodigious gallic nose? why would a girl want to dote on what seemed to me quite unattractive faces? it is not just the face, of course, that is the attraction in these cases, but the voice, the character, the swagger – the whole package. still, it was the face that was there, staring back from the walls. we react strongly to faces, and we read a lot into them. specialized sets of neurons seem to be set aside for recognizing small differences in facial features as the bases of individual recognition (calder and nummenmaa, ; gobbini and haxby, ; ng et al., ; sereno and huang, ). we read emotion from faces with remarkable sensitivity, often relaying that emotion through our own mirror-neuron circuits (calder and nummenmaa, ; moody et al., ; schulte-ruther et al., ). and we react emotionally to faces in complex ways, with greater or lesser degrees of trust, apprehension, defiance, and of course, sexual attraction. but what features make an attractive face? do people agree on those features? and why should those particular features be attractive? there is actually considerable convergence of opinion among behavioral scientists of different stripes on some aspects of these questions. for one thing, infants as young as to months old show a preference for the same faces that adults rate as more attractive, suggesting that criteria of attractiveness are available without the need for much in the way of learning or social conditioning (langlois et al., ). for another, there is remarkable cross-cultural consistency in ratings of facial attractiveness, even when people are rating faces from populations they have never encountered (jones et al. ). what the criteria of facial attractiveness are, however, is in greater dispute. in , langlois and roggman reported on a new method for “blending” facial images on a computer to produce composites that averaged the features of the individual faces they were generated from (langlois and roggman, ). they found remarkable consistency among subjects in rating composite faces as more attractive than individual faces. the higher the number of faces blended, the more attractive the resulting “average” face. langlois and her colleagues further demonstrated that these “average” faces were also preferred by infants and by people of different genetic and cultural background (langlois et al., ). they even suggested as an evolutionary consequence that the preference for average faces serves to prevent fisherian “runaway selection” for particular facial traits. francis galton actually made similar observations in the th century based on superimposing photographs, suggesting that average faces obscured the telltale signs of criminality and depravity that might be apparent in individuals (galton, ). more research soon followed, using computer-manipulated faces to explore the basis of attractiveness and coming up with somewhat different answers. jones presented evidence that more neotenous, or “youthful,” facial features than average are considered more attractive (jones, ), while perrett et al. found a preference for more “feminized” faces than average (perrett et al., ). in both of these cases the preferences were consistent for both male and female subjects rating both male and female faces, whether of same or different genetic and cultural background. but in a follow-up to the perrett et al. study, the same group reported a new twist (penton-voak et al., ). female ratings of male facial attractiveness vary with the raters’ menstrual cycle. although the general preference for somewhat feminized faces was confirmed in this study, women judged to be in the middle of their menstrual cycles showed a shift in preference toward less feminized faces. this tendency was particularly striking when women were asked to rate attractiveness for a partner in a “short-term sexual relationship” versus a “long-term relationship.” the faces used in these studies were “feminized” or “masculinized” on the computer by differential blending of actual male and female faces. but the authors, in interpreting their findings, suggested that in real male faces a similar “feminine-masculine” axis of variation represents a cue to male testosterone levels. a shift in female preference toward higher testosterone men at midcycle and for short-term mating might, they reasoned, be a means for choosing “good genes.” but to make this argument they had to invoke the often challenging logic of the “handicap principle”: high testosterone by itself suppresses immune function (a bad thing); therefore men who flourish despite this handicap must have “good traits” that more than compensate (a good thing). by choosing a manifestly “bad thing,” females are actually choosing a non-manifest “good thing.” (if this logic seems a bit dicey to you, as it often does to me, there is a large literature to wallow in.) by this point, however, the logical scaffolding supporting an adaptive understanding of judgments of facial attractiveness seems to be getting a little top-heavy with assumptions. a computer-generated facial “trait” (relative femininity-masculinity) may or may not correspond to a trait in “real” faces. female preference for this trait may or may not depend on a woman’s actual, rather than inferred, hormonal levels. if the computer-generated facial trait exists in “real” male faces, it may or may not be correlated with actual testosterone levels. and if it correlates with testosterone levels, those levels may or may not be correlated with other male traits that would confer fitness advantage on a woman’s offspring. as the assumptions proliferate, one has to worry about objectivity. are we trying too hard to see in the data what we want to find? in this issue of hormones and behavior, roney and simmons present a study that goes a long way toward reducing the number of assumptions in play. rather than relying on computer-generated faces, they assess women’s ratings of the attractiveness of real male faces. rather than assume that the characteristics of these faces are cues to testosterone levels, they measure the testosterone levels of their male subjects. rather than infer the hormonal status of their female raters from menstrual dates, they measure their estrogen levels. the results demonstrate than the degree of female preference for the faces of men with higher actual testosterone levels is positively correlated with actual female estrogen levels, tracking those levels across the menstrual cycle. beneath face-to- face attraction they discover gonad-to-gonad resonance! but as is always true in science, progress toward resolving one part of a puzzle often helps to bring another part of the puzzle into clearer focus. if women’s preference for men’s faces is really a reproductive state dependent preference for male testosterone levels, what function does this serve? roney and simmons seem content to rely on a “handicap principle” interpretation of this facultative preference. but i suggest that this part of the puzzle now deserves more scrutiny. one issue that merits attention concerns the interpretation of the preference for high testosterone men as a preference for a stable male trait as opposed to a variable male state. men’s testosterone levels change dramatically, not on a regular monthly cycle like female estradiol levels, but in many predictable ways. roney and simmons commendably try to control for circadian variation in their measurements of testosterone, but there are numerous other sources of within-individual variance in testosterone, both short and long term, including mating and parenting status (gray et al., ), exposure to other males and females (roney et al., ), exercise or physical exertion (di luigi et al., ), age (ellison et al., ), and maturational status (di luigi et al., ). the last two on this list perhaps deserve special attention. it is notable that virtually all of the recent studies of facial attractiveness have been conducted with university student populations, both as sources of the faces and as raters (rhodes, ). particularly in this age group male testosterone levels may be strongly affected by a wide range of maturational status. could the estrogen-dependent female preference for higher testosterone men be a preference for more mature late-adolescent men? such a possibility would suggest that women, at least in a similar age group, are not choosing stable male traits, but current male attributes. this would in turn challenge the “handicap principle” interpretation of the functional significance to the preference. advocates of the trait preference interpretation might argue that, theoretically, we expect female choice to shift toward traits rather than states as the context of choice becomes more narrowly limited to short-term mating. but we should always be prepared to have our theoretical expectations challenged by data. one approach to testing the validity of preference for high testosterone as preference for a trait would be to move to a broader age range of both women and men. if male faces are cues to male testosterone state, then female preferences at mid-cycle should converge on young adult male faces, an age when absolute male testosterone is at its peak, as are presumably other transient male states such as competitive ability and sexual virility. if, on the other hand, female mid-cycle preferences are truly for stable male traits, then age-corrected testosterone should emerge as the best predictor of female choice. another question to pursue is the stability of the female preference with changing female state. we have already established that preference varies across the menstrual cycle as a function of female hormonal status. but this has only been clearly demonstrated in one particular age group who may share certain aspects of underlying reproductive strategy as a function of age and parity. would older, higher parity women show the same preference bias, or to the same degree? roney and simmons already invoke in their discussion the necessity of thinking about variation in female fecundity in a natural environment as a context for any functional interpretation. that context not only includes long periods of infecundity due to lactation, but variation in fecundity with age and energetics. in addition, life history theory predicts changes in reproductive effort with age and parity. once we conceive of perceptions of attractiveness as reflections of facultative reproductive strategies, the dimensions of facultative variation proliferate. again, broadening the range of female reproductive states sampled to include lactating and pregnant women, women of different ages and parities, and women in different energetic conditions, might be illuminating. in the end we may be left with the “bogart and belmondo problem.” the world comes into our consciousness as a gestalt, synthesized in our brains from a host of different sensory and cognitive inputs. averageness, youthfulness, masculinity- femininity, current states and stable traits may all play a role in our perceptions of attractiveness. roney and simmons have helped to establish more firmly the fact that our concepts of physical beauty are rooted in our biology, shaped by natural selection, and not merely acquired tastes determined by culture and advertising, as powerful as those influences may be. but although we can be fairly sure our gonads are speaking to us in our judgments of attractiveness, we can’t yet be sure what they are saying. references calder, a. j., nummenmaa, l., . face cells: separate processing of expression and gaze in the amygdala. curr biol. , r - . di luigi, l., et al., . salivary steroids at rest and after a training load in young male athletes: relationship with chronological age and pubertal development. int j sports med. , - . ellison, p. t., et al., . population variation in age-related decline in male salivary testosterone. hum reprod. , - . galton, f., . composite portraits. j anthropol inst gr brit ire. , - . gobbini, m. i., haxby, j. v., . neural response to the visual familiarity of faces. brain res bull. , - . gray, p. b., et al., . marriage and fatherhood are associated with lower testosterone in human males. evol hum behav. , - . jones, d., . sexual selection, physical attractiveness, and facial neoteny. curr anthropol. , - . langlois, j. h., roggman, l. a., . attractive faces are only average. psychol sci. , - . langlois, j. h., et al., . infant preferences for attractive faces: rudiments of a stereotype? devel psychol. , - . langlois, l. h., et al., . what is average and what is not average about attractive faces? psychol sci. , - . moody, e. j., et al., . more than mere mimicry? the influence of emotion on rapid facial reactions to faces. emotion. , - . ng, m., et al., . selectivity for the configural cues that identify the gender, ethnicity, and identity of faces in human cortex. proc natl acad sci u s a. , - . penton-voak, i. s., et al., . menstrual cycle alters face preference. nature. , - . perrett, d. i., et al., . effects of sexual dimorphism on facial attractiveness. nature. , - . rhodes, g., . the evolutionary psychology of facial beauty. ann rev psychol. , - . roney, j. r., et al., . rapid endocrine responses of young men to social interactions with young women. horm behav. , - . schulte-ruther, m., et al., . mirror neuron and theory of mind mechanisms involved in face-to-face interactions: a functional magnetic resonance imaging approach to empathy. j cogn neurosci. , - . sereno, m. i., huang, r. s., . a human parietal face area contains aligned head- centered visual and tactile maps. nat neurosci. , - . paperzb-rev .dvi hidden-beauty charged tetraquarks and heavy quark spin conservation a. ali¶, l. maiani∗, a.d. polosa∗, v. riquer∗ ¶deutsches elektronen-synchrotron desy, d- hamburg, germany ∗dipartimento di fisica, sapienza università di roma, piazzale aldo moro , i- roma, italy and infn sezione di roma, piazzale aldo moro , i- roma, italy abstract assuming the dominance of the spin-spin interaction in a diquark, we point out that the mass differences in the beauty sector m(z′ b )± − m(zb)± scale with quark masses as expected in qcd, with respect to the corresponding mass difference m(z′ c )± − m(zc)±. notably, we show that the decays Υ( ) → (hb( p),hb( p))π+π− are compatible with heavy-quark spin conservation once the contributions of zb,z ′ b intermediate states are taken into account, Υ( ) being either a Υ( s) or the beauty analog of yc( ). we also consider the role of zb,z ′ b in Υ( ) → Υ(ns)ππ decays and of light quark spin non-conservaton in zb,z ′ b decays into bb∗ and b∗b∗. indications on possible signatures of the still missing xb resonance are proposed. preprint # desy - tetraquark interpretation of the hidden charm and beauty exotic resonances has been ad- vanced and studied in considerable detail (see refs. [ ] [ ], and [ ]). in a recent contribution [ ], a new scheme for the spin-spin quark interactions in the hidden charm resonances has been pro- posed, which reproduces well the mass and decay pattern of x( ), of the recently discovered [ ] z ±, c ( ), z ±, c ( ), and of the lowest lying j p c = −− y states. tetraquark states in the large nc (color) limit of qcd have been considered in [ ] and [ ] (see also the review [ ] and references therein). compact tetraquark mesons may have decay widths as narrow as /nc, contrary to previous beliefs, and therefore they are reasonable candidates for a secondary spectroscopic meson series, in addition to the standard qq̄ one. in this letter we consider the extension of the scheme presented in [ ] for the hidden-charm to the hidden-beauty resonances z ±, b ( ) = zb and z ±, b ( ) = z′ b . these resonances are interpreted as s−wave jp g = ++ states with diquark spin distribution (use the notation |s[bq],s[b̄q̄]〉 for diquark spins) |zb〉 = | bq, b̄q̄〉 − | bq, b̄q̄〉√ |z′b〉 = | bq, b̄q̄〉j= ( ) the jp = + multiplet is completed by xb, which is given by the c = + combination |xb〉 = | bq, b̄q̄〉 + | bq, b̄q̄〉√ ( ) assuming the spin-spin interaction inside diquarks to dominate, we expect xb and zb to be degen- erate, with z′ b heavier according to m(z′b) − m(zb) = κb ( ) where κb is the strength of the spin-spin interaction inside the diquark. a similar analysis for the hidden-charm resonances has produced the value [ ] κc = m(z ′ c) − m(zc) ≃ mev ( ) the qcd expectation is κb : κc = mc : mb. the ratio can be estimated from the masses reported in [ ] mc mb ≃ . . = . ( ) giving κb ≃ mev, which fits nicely with the observed z′b − zb mass difference (≃ mev). next we consider another crucial prediction of qcd, namely conservation of the heavy quark spin in hadronic decays. we recall that zb,z ′ b are observed in the decays of Υ( ) Υ( ) → zb/z′b + π → hb(np)ππ ( ) the Υ( ) is usually reported as the Υ( s) since its mass is close to the mass of the s state predicted by potential models. however, a different assignment was proposed in [ ], namely Υ( ) = yb, the latter state being a p−wave tetraquark analogous to the y ( ). a reason for this assignment is the analogy of Υ( ) decay ( ) with y ( ) → zc( ) + π, with y ( ) being the the first discovered y state [ ]. current experimental situation about Υ( ) is still in a state of flux. in our opinion, the possibility that Υ( ) is an unresolved peak involving both the Υ( s) and yb, reported by belle some time ago [ ], is plausible, providing a resolution of the observed branching ratios measured at the Υ( ) [ ]. however, this identification is not a requirement in the considerations presented below. in fact, following the assignment of y ( ) as a p−wave tetraquark with scc̄ = [ ], one sees that in both cases the initial state in ( ) corresponds to sbb̄ = . as is well known hb(np) has sbb̄ = , pointing to a possible violation of the heavy-quark spin conservation, as suggested in [ ]. we show now that the contradiction is only apparent. expressing the states in the the basis of definite bb̄ and qq̄ spin, one finds |zb〉 = | qq̄, bb̄〉 − | qq̄, bb̄〉√ |z′b〉 = | qq̄, bb̄〉 + | qq̄, bb̄〉√ ( ) define gz = g(Υ → zbπ)g(zb → hbπ) ∝ 〈hb|zb〉〈zb|Υ〉 gz′ = g(Υ → z′bπ)g(z′b → hbπ) ∝ 〈hb|z′b〉〈z′b|Υ〉 ( ) where g are the effective strong couplings at the vertices Υ zb π and zb hb π. therefore, for both assignments of Υ( ), eq. ( ) and heavy quark spin conservation require gz = −gz′ ( ) in ref. [ ] the amplitude for the decay ( ) is fitted with two breit-wigners corresponding to the zb,z ′ b intermediate states. table i therein, that we transcribe here in table , shows the relative normalizations and phases obtained by the fit, for decays into hb( p) and hb( p). within large errors, consistency with eq. ( ), that is with the heavy-quark spin conservation, is apparent. it is interesting that the same conclusion was drawn using a picture in which zb,zb′ have a “molecular” type structure [ ] zb = |b,b̄∗〉 − |b̄,b∗〉√ z′b = |b∗,b̄∗〉j= ( ) it is conceivable that the subdominant spin-spin interactions may play a non negligible role in the b-systems, as the spin-spin dominant interaction is suppressed by the large b quark mass. in hb( p)π +π− hb( p)π +π− relative normalization . ± . + . − . . + . + . − . − . relative phase + + − − + + − − table : values of |gz/gz′| and of the relative phases (in degrees), for hb( p),hb( p), as reported by [ ]. this case the composition of zb,z ′ b indicated in eq. ( ) would be more general: |zb〉 = α| qq̄, bb̄〉 − β| qq̄, bb̄〉√ |z′b〉 = β| qq̄, bb̄〉 + α| qq̄, bb̄〉√ ( ) but the ratio gz/gz′ would still be unity. to determine α and β separately, one has to resort to sbb̄ = → sbb̄ = transitions, such as Υ( ) → Υ(ns)ππ where n = , , . the effective couplings analogous to ( ) would be fz = f(Υ → zbπ)f(zb → Υ(ns)π) = |β| 〈Υ(ns)| qq̄, bb̄〉〈 qq̄, bb̄|Υ〉 fz′ = f(Υ → z′bπ)f(z′b → Υ(ns)π) = |α| 〈Υ(ns)| qq̄, bb̄〉〈 qq̄, bb̄|Υ〉 the dalitz plot of these decays indicate indeed that a sizeable part of the transitions proceeds through zb and z ′ b [ , ]. parametrizing the amplitude in terms of two breit-wigner, one would determine the ratio α/β. as a side remark, we observe that a fierz rearrangement similar to the one used in ( ) puts together bq̄ and qb̄ fields |zb〉 = | bq̄, qb̄〉j= |z′b〉 = | bq̄, qb̄〉 + | bq̄, qb̄〉√ ( ) the labels bq̄ and bq̄ could be viewed as indicating b and b ∗ mesons, respectively, leading to the prediction of the decay patterns zb → b∗b̄∗ and z′b → bb̄∗ [ ]. this would not be in agreement with the belle data [ ]. we remark however that this argument rests on conservation of the light quark spin which, on the contrary, may change when the color octet pairs which appear in ( ), evolve into pairs of color singlet mesons. therefore predictions derived from ( ) are not as reliable as those derived from ( ). finally we comment on the expected positive charge conjugation state, xb. on the basis of the assumed spin-spin interaction, one predicts m(xb) ≃ m(zb) ≃ mev. such a state has been searched by atlas [ ] in the region < m < mev looking for the decay xb → Υ( s)ππ ( ) so far with negative results. in ref. [ ], it is noted that the near equality of the branching ratios for x( ) → j/ψ π and x( ) → j/ψ π can be understood if x( ) is predominantly isosinglet. the isospin allowed decay in j/ψ ω is phase space forbidden and the decay in the j/ψ ρ mode, although isospin forbidden, is phase space favoured, leading to similar rates. in the xb decay, both ω and ρ channels are allowed by phase space, so that, if xb is isos- inglet, the dominant mode would be into Υ( s) ω. the suggestion therefore is to look at the decay xb( ) → Υ( s) π with the π in the ω mass band, in parallel with the search for the xb( ) → Υ( s) π channel with the π in the ρ band. acknowledgements we thank christoph hanhart for interesting discussions. references [ ] l. maiani, f. piccinini, a. d. polosa and v. riquer, phys. rev. d , ( ) [hep- ph/ ]. [ ] s. j. brodsky, d. s. hwang and r. f. lebed, phys. rev. lett. , ( ) [arxiv: . [hep-ph]]. [ ] a. ali, c. hambrock, i. ahmed and m. j. aslam, phys. lett. b , ( ) [arxiv: . 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[hep-ex]. perception, , volume , pages – doi: . /p age and beauty are in the eye of the beholder dylan g kwart , tom foulsham §, alan kingstone department of experimental psychology, university of oxford, oxford, uk; department of psychology, university of essex, wivenhoe park, colchester co sq, uk; e-mail: foulsham@essex.ac.uk; brain and attention research laboratory, department of psychology, university of british columbia, vancouver, canada received october , in revised form july abstract. how “old” and “attractive” an individual appears has increasingly become an individual concern leading to the utilisation of various cosmetic surgical procedures aimed at enhancing appearance. using eyetracking, in the present study we aimed to investigate how individuals perceive age and attractiveness of younger and older faces and what “bottom–up” facial cues are used in this process. one hundred and twenty eight digital images of neutral faces of ages ranging from to years were paired and presented to subjects who judged age and attractiveness levels while having their eye movements recorded. there was an effect of face attractiveness on age-rating accuracy, with attractive faces being rated younger than their true age. similarly, stimulus age affected attractiveness ratings, with younger faces being perceived as more attractive. judgments of age and attractiveness were tightly linked to fixations on the eye region, along with the nose and mouth. it is thus likely that cosmetic surgical procedures targeted at the eyes, nose, and mouth may be most efficacious at enhancing one’s physical appearance. keywords: age, aging, attractiveness, cosmetic surgery, eye movement, face perception introduction how “old” or “attractive” an individual appears plays a major role in determining the outcomes of one’s life-course trajectory including vocational success, social relationships, mental health, and overall well-being (bleske-rechek and buss ; chaiken ; dickey- bryant et al ; farina et al ; kligman and graham ). accordingly, an increasing number of individuals are making use of hundreds of invasive and non-invasive cosmetic surgical procedures, hoping to improve how old or attractive they are perceived (american society for aesthetic plastic surgery ; clarke and griffin ). though past research has revealed that cosmetic surgical procedures enhancing appearance may improve patients’ psychological health (see castle et al ; honigman et al ; rankin et al ), little work has examined the specific aspects of a face that are diagnostic of age or attractiveness. the idea that age and attractiveness perception are linked arises from evolutionary theories of interpersonal attraction, which purport that attractive mates are those who appear youthful, viable, and physically vital (berry ; burt and perrett ; jones ). past experimental research has tested these ideas with studies involving subjective rating of the age and attractiveness of face images. in a variety of related studies it has been shown that subjects tend to rate older faces as unattractive, and, similarly, when rating age, attractive faces are perceived as younger (ebner ; foos and clark ; mckelvie ; wernick and manaster ). furthermore, recent literature has revealed that face age and attractiveness cues directly influence the neuropsychological and perceptual processing of facial stimuli (ebner et al ; george and hole ; rellecke et al ; sui and liu ), suggesting that attentional processes may be tuned to specific diagnostic biomarkers of age and attractiveness contained within a face. § author to whom all correspondence should be sent. d g kwart, t foulsham, a kingstone older and younger faces are physically different in many ways. for example, characteristic age-related features, including skin and hair topography, colour heterogeneity, and texture, have been shown to be “telling” of age (matts et al ). structural and facial surface features also vary with age through either weight redistribution or growth resulting in stereotyped changes in skull and forehead shape, broadening of the chin, lengthening of the ears and nose, changes in the size of the eyes and surrounding eye region, and retraction of the lips (albert et al ; bruce and young ; burt and perrett ; ebner ). research has also demonstrated that, apart from age, attractiveness tends to correlate most with face averageness and symmetry (dykiert et al ; valentine et al ; zaidel and cohen ), both of which can be affected by the above structural facial alterations associated with age. studies involving stimulus manipulation and subjective reports have revealed that specific age-sensitive facial features including the eye region are important in judging facial qualities such as age (george and hole ; rexbye and povlsen ; valentine et al ). facial stimulus manipulation, while important to research control, can result in distorted face images that introduce salience artifacts that may not accurately capture the natural perceptual processes associated with age and attractiveness. thus, different tools enabling insight into an observer’s attentional processes may reveal mechanisms involved in age and attractiveness perception. eyetracking involves the real-time monitoring of eye movement behaviour to reveal gaze targets which reflect the priorities of visual attention (duchowski ; parkhurst and niebur ). eyetracking has been used widely in the field of facial processing to determine visual cues in face recognition, emotion detection, and social scenes (bindemann et al ; birmingham et al , ; calvo and lang ; henderson et al ; lundqvist and ohman ; pelphrey et al ; walker-smith et al ). while it is accepted that eye movement behaviour differs with a given task (yarbus ), or even with gaze starting position (arizpe et al ), fixations towards the eye region are consistently overrepresented (bindemann et al ; birmingham et al , , ; nguyen et al ; henderson et al ). however, this tendency does seem to be modulated by task instruction (lundqvist and ohman ), suggesting visual cues may be differentially utilised in specific perceptual tasks. on this basis, we sought to determine whether different facial cues are used in the age- and attractiveness-rating paradigms described above. recently nguyen et al ( ) used an eyetracking paradigm to address how people process older facial stimuli while making subjective ratings of face age and fatigue. in both tasks, the authors found that the eyes were looked at most frequently followed by the forehead and nose. further, they noticed that the glabella, the region between the eyebrows, was looked at more in faces rated the oldest. the authors concluded that cosmetic procedures should be targeted toward the eye region when intended to enhance the appearance of an individual. in addition to their novel approach, the data presented in the nguyen et al study raise certain methodological questions. first, the faces in nguyen et al’s study were presented individually, at the centre of the computer monitor facing participants where a fixation cross was first presented. this design makes it possible that the predominance of fixations on the eye region may have been partly because participants initially fixated at the centre of the screen, and were subsequently biased to look at this location once the face was presented. by way of contrast, we presented participants with two faces at a time, separated by a fixation cross at the centre of the screen. because fixation began on the space between the faces, eye movements were required to select one of the faces, as well as the component features, and thus fixations were not preferentially biased by the starting location (arizpe et al ). an additional advantage to presenting two faces at a time is that the judgment task involves a relative comparison, a strategy common in everyday life (jones ; tennis and dabbs ). age and beauty are in the eye of the beholder further, in our study stimuli represented a wide range of ages ( – years) as we predicted that young observers might not respond equally to all facial stimuli, independently of face age (anastasi and rhodes ). for this reason, we also analysed assessors’ ratings made during the judgment tasks to specifically investigate age rating accuracy (since the actual age of facial stimuli was known) and variance in attractiveness ratings across the face-age span. nguyen et al only presented judgers with older faces (actual ages unknown), yet discuss in their results differences in eye-movement behaviour towards ‘older’ (> years) versus ‘younger’ (< years) faces. by investigating broader trends in rating and eye movement behaviour across faces of varying age and attractiveness (including actual younger adult faces) we aimed to qualify these results. since the majority of past research in the field has characterised the perception and effects of beauty or appearance in terms of attractiveness, we asked participants to rate faces along two dimensions: age and attractiveness, instead of fatigue (berry ; langlois et al ). while nguyen et al may have predicted that perception of fatigue would be closely related to age judgments, our methodological changes provide a bridge to the literature on attractiveness, which along with age is the main dimension which people seek to alter with cosmetic surgery. it is known that eye-movement behaviour changes when viewers are asked different questions about a visual stimulus (yarbus ), thus we can extend nguyen et al’s findings by asking whether there is a bias to fixate the eye region regardless of whether one is estimating someone’s age or rating his/her attractiveness. moreover, given that a bias for people to look at the eyes of others is well established in visual cognition (birmingham et al , ; henderson et al ), it is important to consider whether this bias is moderated by the task. nguyen et al were the first to use eyetracking to investigate the perceptually, and potentially clinically important, facial regions used while making assessments of a person’s age and physical appearance. with the aforementioned methodological changes we expected to gain greater insight into how people judge age and beauty, thereby replicating and expanding nguyen et al’s original work. we aimed to utilise our participants’ subjective ratings to investigate how age judgment-accuracy changes as a function of face age and attractiveness, as well as whether face age affects perceived attractiveness. furthermore, we used eyetracking to test how facial features are recruited in age and attractiveness judgment tasks, and analysed whether such tasks rendered differences in eye-movement behaviour. specifically, we predicted that visual fixations would be overrepresented in the eye region; that faces of different ages and attractiveness levels would be rated differently—with age and attractiveness rating levels being inversely related—and that these differences in ratings would be reflected in overall eye-movement behaviour. materials and methods . stimulus preparation one hundred and twenty eight male and female faces with known ages ranging from to years in age were retrieved from the cal/pal face database (minear and park ) for use in the present study. this database consists of face images of ohio and southern michigan locals asked to stand in their street clothing with a neutral face in front of a neutral grey background under natural lighting. photos were taken in two student unions, a shopping mall, and a variety of older adult festivals (minear and park ). this database has been widely utilised in perceptual research involving neutral facial stimuli across the lifespan (ebner ; platek and thomson ; wright et al ). in our study caucasian stimuli were selected and cropped to include the entire head (including hair) and neck region. extraneous jewelry and clothing were also cropped out with adobe photoshop cs. final images were all around × pixels in size. d g kwart, t foulsham, a kingstone these faces were organised into categories based on actual face age (grouped into seven decades: – , – , and so on up to – years), gender (male or female), and attractiveness (attractive or unattractive), resulting in possible age/gender/attractiveness classifications ( × × ). faces were first split as attractive or unattractive based on the subjective consensus of our research group, with each face being rated on the point scale by the authors. this initial dichotomization ( – = attractive; – = unattractive) was carefully applied and later validated by participants’ actual attractiveness response ratings. faces were paired into representatives of all possible age, gender, and attractiveness combinations, and pairings were compiled into a single set. a point scale for either age rating ( – to – years) or attractiveness level ( = not at all attractive, = extremely attractive) was placed under the two images. the images were separated by a central fixation cross. two example pairs of faces are shown in figure . two possible variations of each pair were compiled and used equally across participants: one where a given face of the presented pair was on the left and another where it was on – – – – – – – – – – – – – – – – – – – – – – – – – – – – figure . stimulus preparation and sample age-rating trial. split bilaterally by a central fixation cross presented first, two faces were paired and simultaneously presented. subjects estimated the age of each face based on the age-rating scale presented below each image ( – , – … – ). when rating attractiveness, the age-rating scale was replaced with a point likert scale ( = not at all attractive; = neutral; = extremely attractive). responses were recorded by a mouse click on the corresponding box. (a) boxes represent ias used for looking behaviour analysis (left = year old attractive male, right = year old attractive male). (b) blue circles represent visual fixations; numerical values represent fixation duration in ms (left = year old attractive male; right = year old unnattractive female). note: f = forehead; g = glabella; e = eye region; n = nose; ck = cheek; l = lips; cn = chin. [in colour online, see http://dx.doi.org/ . /p ] (a) (b) age and beauty are in the eye of the beholder the right. this procedure ensured that the side of the screen in which a face appeared was balanced across participants, as was the order of the two judgment conditions. within each condition (age or attractiveness rating), all trials were randomly presented with each face pair presented once per task. . equipment and apparatus eye-movement behaviour was recorded using a sr research eyelink eyetracker. this equipment recorded monocular eye position throughout the trials, using the pupil image and the corneal reflection at hz. saccades and fixations were defined using the standard eyelink algorithm based on velocity and acceleration thresholds (of ° s– and ° s– , respectively). participants were asked to keep their heads fixed on a chin-rest approximately inches from the centre of a inch × . inch ( inch diagonal) dell lcd monitor on which the paired facial stimuli were presented with a central fixation cross. the screen had a resulting visual angle of approximately deg by deg, and faces were about deg wide. facial regions were defined on each face as interest areas (ias) using the area selection tool on eyelink’s dataviewer software, with regions based on the study of nguyen et al ( ), and included left and right eye regions, glabella, nose region, cheeks, lips, chin, and forehead, as shown in figure a. bilateral interest areas were equally sized and scaled to the size of each face stimulus’ size. fixation count and dwell times (in ms, and in percent of trial time) were calculated for each ia. . procedure and participants prior to each task, the eyetracker was aligned with the participant’s right eye and a brief -point calibration took place. each participant then completed the two judgment tasks, the order of which was counterbalanced across participants. thirteen university of british columbia students (six males; mean age = . years, sem = . years) were tested in this study for course credit, or a small stipend. all participants signed an informed consent form prior to experimentation. ethics committee approval was obtained for this study. . . judging age. in each trial, participants were presented with a drift correct cross at the centre of a white screen (at which point fixation was confirmed at this location). a face pair then appeared, and participants were instructed to use the computer mouse to rate the age of each face by clicking on the correct age-range box (see figure for a sample of the rating scales) under each face. participants were allowed to change the rating choice of the face they rated first (rating was acknowledged with the appearance of an asterisk above the scale); when the rating of the second face was completed the trial was terminated and the drift correct cross reappeared, signaling the next trial. there was no time limit, ratings proceeded in a self-paced fashion and it was up to the participant which face was rated first. . . judging attractiveness. the same protocol was followed in this condition, however participants were instructed to rate the attractiveness of each face on a point scale, and the position of the faces (left or right side of the screen) was reversed from that used in the previous judgment set. following the completion of both tasks participants were debriefed about all experimental initiatives. results we presented participants with a range of different face stimuli, and in particular we categorised each face according to age and attractiveness. before our analyses, we first validated our subjective grouping of attractive/unattractive faces by finding a significant effect of predefined face attractiveness on participant attractiveness ratings (f , = . , p < . , p h = . ), where “attractive” faces were indeed rated higher on the attractiveness scale (m = . , sem = . ) compared to unattractive faces (m = . , sem = . ). d g kwart, t foulsham, a kingstone to investigate the effect of these dimensions on behaviour, we dichotomised face age into old (> years, n = ; m = . , sem = . ) and young (< years, n = ; m = . , sem = . ). in each case, we then used a × repeated-measures anova to compare the means for each type of face with factors of age and attractiveness. . ratings results . . does attractiveness influence age ratings? first, we calculated an age rating error score by subtracting the known age decade from the age rating, converted into a point scale ( – years = , – years = , etc) to examine how well our young subjects estimated the age of faces from different age groups and to see whether these estimates were affected by attractiveness. on this measure a positive score (for example, a – year old face rated as – years old; error = ) indicated that the participant overestimated the age of the face, a negative score signified an underestimate, and an error of zero meant that they correctly chose the right decade. we analysed these values with an age of face (young, old) × attractiveness (attractive, unattractive) × repeated-measures anova. there was a significant effect of stimulus face age on age rating error (f , = . , p < . , p h = . ) with mean rating errors of young faces being positive (ie they were rated older than their true ages; m = . , sem = . ), and those for older faces being negative (ie they were rated younger than their true ages; m = – . , sem = . ). further, a significant effect of face attractiveness on age rating error (f , = . , p < . , p h = . ) shows that, on average across all ages, attractive faces were rated approximately . years younger than their actual associated decade of age (m = – . , sem = . ). conversely, the age of unattractive faces was slightly overestimated (m = . , sem = . ). a marginally significant interaction between stimulus face age and face attractiveness was found on age rating error (f , = . , p = . , p h = . ). follow-up, paired-samples t-tests demonstrated that the effect of attractiveness was reliable: attractive faces were rated as younger than unattractive faces, both in young faces (t = . , p < . , d = . ) and in older faces (t = . , p < . , d = . ), but the difference was larger in the former. young faces were rated . years younger than their associated decade of age, on average, if they were attractive, while the mean attractiveness benefit for old faces was . years. a summary of these results is shown in figure . . . does face age influence attractiveness ratings? a summary of the mean attractiveness rating results for each face age decade group is depicted in figure . for analysis, mean a ttr ac tiv en es s ra tin g face age/years figure . summary of mean attractiveness rating results by stimulus face age. a significant effect of face age exists on attractiveness ratings. dots represent mean rating ± sem. m ea n ra tin g er ro r (a ge ra tin g – re al a ge ) . . . – . – . – . attractive unattractive face attractiveness figure . summary of the mean age-rating error results (age rating – real age) by face age (young: < years old; old: > years old) and attractive level (attractive versus unattractive). bars represent mean accuracy or error ± sem. young old age and beauty are in the eye of the beholder attractiveness ratings were again entered into a × repeated-measures anova with face age (young vs old) and attractiveness (attractive vs unattractive) as previously described. there was a significant effect of face age on attractiveness ratings (f , = . , p < . , p h = . ), where young faces were rated as more attractive (m = . , sem = . ) than older faces (m = . , sem = . ). moreover, a significant interaction between face age and face attractiveness on attractiveness ratings was found (f , = . , p = . , p h = . ). looking at the ratings in each group of this × design we can see that the difference in mean attractiveness rating between young and old faces is larger for attractive faces (young: m = . , sem = . ; old: m = . , sem = . ; t = . , p < . ) than unattractive faces (young: m = . , sem = . ; old: m = . , sem = . ; t = . , p < . ). the standardised effect size in each case is similar (ds = . and . , respectively). . eye movement results participants took a mean of . s (sem = . s) to rate both faces on age, and they made . fixations per trial on average (sem = . ). attractiveness judgments were made more quickly (m = . s, sem = . s) and with fewer fixations than age judgments (m = . s, sem = . s). paired-sample t-tests confirmed that the two tasks were different in both duration (t = . , p < . , d = . ) and number of fixations (t = . , p < . , d = . ). the first fixation was always on the centre, due to the appearance of the fixation point before each stimulus. figure b shows an example of the fixations made by one subject viewing a pair of faces. the remainder of our results focus on how often, and how early, different regions of interest were fixated in the different tasks. we performed this analysis by defining seven areas of interest for each face: eyes, glabella, nose, cheeks, mouth, chin and forehead. . . how often were different facial features fixated? figure shows the proportion of all fixations made on each of the regions of interest, for the age and attractiveness rating tasks. in each case, fixation frequencies were summed across both faces in the display and expressed as a proportion of the total number of fixations made in each trial. a × repeated-measures anova was computed with factors of task (age vs attractiveness rating) and region type. this analysis demonstrated that there was a reliable effect of region type on the proportion of fixations (f , = . , p < . , p h = . ). there was no main effect of task (f , = . , p = . , p h = . ), and no interaction (f , = . , p = . , p h = . ), age rating attractiveness rating pr op or tio n of fi xa tio ns . . . . eye s gla bel la nos e che eks mo uth chi n for ehe ad figure . proportion of visual fixations on given facial interest areas for age and attractiveness rating tasks. bars represent the proportion of fixations (a numeric decimal of ) per whole trial ± sem for both tasks. both the eyes and nose region are overrepresented as regions fixated on in both age and attractiveness rating tasks. facial region d g kwart, t foulsham, a kingstone indicating that similar regions were fixated in both tasks. in both tasks, the eyes were the most frequently inspected regions, and they were looked at significantly more often than all other regions except the nose (bonferroni-adjusted paired comparisons, vs glabella: t = . , d = . ; vs cheeks: t = . , d = . ; vs mouth: t = . , d = . ; vs chin: t = . , d = . ; vs forehead: t = . , d = . ; all ps < . ; vs nose: t = . , d = . , p = . ). the nose was fixated more often than the glabella (t = . , d = . ), cheeks (t = . , d = . ), mouth (t = . , d = . ), chin (t = . , d = . ), or forehead (t = . , d = . ; all ps < . ). the cheeks were fixated more often than the chin (t = . , d = . , p = . ), but no other comparisons were reliable. it is also important to consider the relative size of the regions of interest, as we might expect larger regions to be fixated more often by chance alone. in our case, the pixel area of regions could not account for the differences in fixation frequency. for example, on average across the face stimuli, the forehead region covered twice as much area as the eye regions, yet it received far fewer fixations. a series of one-sample t-tests compared the proportion of fixations on each region to the relative areas of that region, expressed as a proportion of the total area of all regions. the eyes and the nose were fixated significantly more often than expected given their area (t s = . and . , ds = . and . , respectively, ps < . ). the cheeks (t = . , d = . , p < . ), mouth (t = . , d = . , p < . ), chin (t = . , d = . , p < . ), and forehead (t = . , d = . , p < . ) were fixated significantly less often than their area would suggest, while the glabella was fixated in accordance with its relative area (t < ). moreover, the results from the first fixation were very similar to those from all fixations: the eyes and nose were fixated preferentially, and other regions were rarely selected on the first fixation. . . does face age or attractiveness affect eye movements? we then compared participant means for each type of face, looking at the total time spent fixating on the face, as well as the proportion of fixations on different regions of interest. the results for total time spent fixating a face are summarised in figure . there was no effect of age on the total time spent fixating a face, in either task (age rating: f , = . , p = . , p h = . ; attractiveness rating: f , = . , p = . , p h = . ). however, there was an effect of attractiveness in both tasks. when judging age, unattractive faces were looked at for longer than attractive faces (f , = . , p < . , p h = . ). interestingly, the direction of this effect was reversed when judging attractiveness: in this case attractive faces were actually looked at for longer than unattractive faces (f , = . , p < . , p h = . ). the interaction between face age and face attractiveness was not reliable in either task (age rating: f , = . , p = . , p h = . ; attractiveness rating: f , < ). attractive unattractive (a) (b) fi xa tio n tim e/ m s fi xa tio n tim e/ m s young old face age young old face age figure . summary of trends depicting time spent fixating on a face. unattractive faces are looked at longer when judging age (a), whereas attractive faces are looked at longer when rating attractiveness (b). age and beauty are in the eye of the beholder next, we computed separate × × repeated-measures anovas for each task, with factors of age, attractiveness, and region of interest. the proportion of fixations on each region of interest interacted with both face age and face attractiveness, in both ratings tasks. these interactions were inspected further with pairwise comparisons between old/young and attractive/unattractive faces, in order to see which regions were inspected differently for each type of face. the results for the age rating task are summarised in table . when rating age, region of interest interacted with face age (f , = . , p < . , p h = . ) and face attractiveness (f , = . , p < . , p h = . ), but these effects were qualified by a three- way interaction between age, attractiveness and region of interest (f , = . , p < . , p h = . ). in attractive faces, the only difference between old and young faces lay in the frequency of fixations made on the mouth. participants spent more fixations on the mouths of young attractive faces than those of old attractive faces (t = . , d = . , p < . ). in unattractive faces, the nose was fixated more often in young faces than in old faces (t = . , d = . , p < . ). no other comparisons were significant. when rating attractiveness, a different pattern was observed. in this task, face age had only a marginal effect on the fixations allocated to each region (interaction with region: f , = . , p = . , p h = . ), but the interaction between region of interest and face attractiveness was significant (f , = . , p < . , p h = . ). there was no three-way interaction (f , < ), so old and young faces were combined and we compared the regions fixated in attractive and unattractive faces (see table ). the nose and mouth of attractive faces were fixated more often than unattractive faces (nose: t = . , d = . , p < . ; mouth: t = . , d = . , p < . ). the number of fixations involved here was rather small. however, the standardised effect sizes were medium to large in magnitude and statistically significant. to summarise this analysis, therefore, while the eyes were invariably fixated in all types of face, fixations on the nose and mouth may be particularly diagnostic for age and attractiveness. . . eye movements and the comparison between faces. our design, featuring two faces side-by-side, raises the question of whether participants overtly compared the two faces when making their decision. one way in which to investigate this is to look at the frequency with which saccades moved from one face to the other. in a completely serial strategy, participants would look at one face and decide upon its age/attractiveness before making a single shift to the other face. in contrast, a strongly comparative strategy might result in many more between-face shifts of attention, perhaps between particular features, before making both rating responses towards the end of the trial. table . proportion of fixations on each region of interest on different faces during the age rating task. region of interest attractive faces unattractive faces young old young old m sem m sem m sem m sem eye . . . . . . . . glabella . . . . . . . . nose . . . . . * . . * . cheeks . . . . . . . . mouth . * . . * . . . . . chin . . . . . . . . forehead . . . . . . . . note: means for old and young faces are reliably different at * p < . . d g kwart, t foulsham, a kingstone qualitative and quantitative evaluation of participant behaviour indicated a largely serial strategy. on most trials, participants inspected and rated one face before moving on to the other. on average, participants made two between-face saccades per trial, and this did not differ between tasks (t < ). this was equivalent to an average of only % of the total number of saccades in the experiment, with the remainder shifting attention within a single face. moreover, when a shift from one face to another did occur, in only a minority of cases was this directed between matching interest areas (eg from the nose in face a to the nose in face b, which would be a good indication of a comparison strategy). these matching saccades accounted for only % of between-face saccades, and again this did not differ between tasks (t < ). most participants started by fixating and rating the face on the left of the screen, before moving on to the one on the right. discussion until recently, no research has investigated how individuals make judgments about physical appearance in relation to the looking behaviours and facial biomarkers utilised in these tasks. most work has relied on stimulus distortion, subjective ratings, or simple electrophysiological techniques to provide insight as to how people perceive qualities of faces including age and attractiveness (ebner ; ebner et al ; foos and clark ; george and hole ; matts et al ; rellecke et al ; wernick and manaster ). nguyen et al were first to describe the eye region as the primary tell-all facial area used when judging qualities of physical appearance. the present study sought to extend these novel results with a closer inspection of the accuracy of age ratings and their relation to attractiveness. presenting a central fixation cross prior to the presentation of the facial stimuli prevented visual fixations from already being localised close to the eye region, thus allowing us to obtain a purer measure of where initial saccades were targeted. although our stimuli may have encouraged a comparison between faces, eye movement patterns suggested that this was not performed by moving back and forth between the faces. we observed that fixations towards the eyes and nose were significantly overrepresented, as expected based on nguyen et al’s results. upon further detailed analysis, our results demonstrate how the nose and mouth regions were differentially recruited when judging either age or attractiveness. using facial stimuli that spanned from youth to older adulthood allowed us to specifically analyse how eye movements and subjective perceptions change depending on the age of such faces. viewers showed a negative bias towards older adults, rating them as less attractive than younger people. a negative bias also led unattractive faces (regardless of age) to be table . proportion of fixations on each region of interest on different faces during the attractiveness rating task. region of interest attractive faces unattractive faces m sem m sem eye . . . . glabella . . . . nose . ** . . ** . cheeks . . . . mouth . * . . * . chin . . . . forehead . . . . note: means for attractive and unattractive faces are reliably different at * p < . ; ** p < . . age and beauty are in the eye of the beholder rated older than age-matched attractive faces. this was particularly true in younger people, and attractive young faces elicited the most accurate age ratings. our choice in selecting attractiveness levels as a judgment task resulted in a similar set of findings that nguyen et al purported with regards to fatigue levels and age: age and attractiveness levels are perceptually linked, with older faces being rated less attractive and more fatigued. in our study, attractiveness ratings decreased gradually with face age, and we expect that perceived fatigue levels would increase in the same manner. judgments of overall attractiveness may be based on a “fatigue-factor”, alongside dimensions such as structural symmetry, definition of features and skin tone (jones et al ). the raw rating results for both age and attractiveness judgment tasks contribute to the growing field of psychology interested in how views and interpretations of human faces are made. we saw that face attractiveness predicts the accuracy of age judgments where attractive faces are rated as younger than unattractive ones. interestingly, subjects tended to rate younger faces older than they actually were, while older faces were commonly rated younger. the marginal interaction found between face age and attractiveness on age rating error can be interpreted such that observers, who were not good at rating older faces in general, were not as influenced by attractiveness as in the (better discriminated) younger faces. furthermore, participants favoured younger faces compared to older faces when judging overall attractiveness and the interaction between face age and attractiveness on attractiveness ratings (larger rating differences exist for young vs old faces in attractive people than unattractive people) demonstrates that for unattractive faces the effect of age is negligible. the observed link between judging age and attractiveness raises some interesting questions about the potential differences reflected in eye movements during these two tasks. in general, both judgment tasks elicited the same eye movement behaviour, suggesting that the facial regions targeted in age and attractiveness perception would be efficacious targets for cosmetic intervention aiming to alter perception of these characteristics. the drive to look at these certain features suggests that these patterns are under “top–down” control, and reflect the fact that these features are important for both tasks. nguyen et al also found a disproportionate number of fixations on the eyes and nose, a pattern that we replicated for age and attractiveness judgments. on the other hand, our participants did not show significant fixations on the forehead and glabella, as reported in that same study. while the inconsistency in findings for the forehead seems significant, given the large amount of facial area taken up by this region, the small size of the glabella, its proximity to the eyes, and the resolution of the eye tracker used by nguyen et al (their eyetracker recorded at the rate of – hz with an accuracy of . º visual angle whereas ours recorded at hz with an accuracy of approximately . °– . º), renders the utility of the glabella in perceptual tasks as questionable. our analysis of fixations by face type extends the general picture of eye-movement behaviour by showing which regions were inspected in faces that were subsequently rated differently. interestingly, although the eyes were fixated most frequently, the time spent on this feature was not diagnostic of face age or attractiveness. in fact, the nose and the mouth were most diagnostic for these tasks, with younger and more attractive faces drawing more fixations to these regions. this provides an incentive for further research into salient differences between these regions in old/young and attractive/unattractive faces, as well as into the efficacy of cosmetic interventions targeting these areas. unlike previous studies, which have often used a single face presented for a fixed duration, participants in the present study were free to distribute their gaze between the two faces on the screen for as long as they liked. we found a dissociation between the two tasks in terms of the length of time spent on each face. in general, subjects were the least accurate at rating the age of unattractive faces, and this lack of confidence may explain the increased d g kwart, t foulsham, a kingstone time spent looking at such faces in the age rating task. whereas in the attractiveness rating task, attractive faces were looked at for longer, perhaps because when beauty is the selection feature individuals dwell longer on such stimuli that can provide aesthetic pleasure. this bias toward attractive faces is congruent with evolutionary theories on attractiveness perception and contributes to our discussion of attentional biases to certain facial stimuli. in general, these theories imply that motivational states are conditioned through adaptation and thus create attentional biases towards increasing reproductive opportunities (maner et al ). it has been strongly suggested that attention is specifically directed at individuals of the opposite sex with evolutionarily attractive qualities (young in appearance, fertile- looking, symmetrical, etc) or to other physically attractive members of the same sex who are considered threats or “intrasexual competition” (li and kenrick ; maner et al , ). therefore, these evolutionary theories of attention explain our findings that young participants are significantly more attentive to other young attractive faces. furthermore, these theories also predict that the same biases will be shown across the lifespan (even in older adults) or within gender categories. it remains possible that the current understanding from the present and other recent studies is limited to the specific younger sample of the population that was used. for example, it is possible that young faces are deemed more attractive because all the viewers rating the facial stimuli were in that age group. when younger individuals view older adults they may make stigmatisations or judgments differently from the way in which older viewers rate similarly aged faces. factors including social agism, the media’s perceptions and other psychological theories may cause raters of different ages to respond to aging faces differently. it is also possible that the facial features recruited by older viewers, and thus the eye-movement behaviour during rating, may differ from those reported. future research will be directed at teasing out these possible age differences and determining how cosmetic intervention should be specifically applied towards the middle and older adult population. in sum, our results show how judging age is affected significantly by overall face attractiveness, and that attractiveness rating and face age are tightly correlated. we found that the eye region, along with the nose and mouth, were significantly and differentially overrepresented amongst regions fixated when judging age and attractiveness. assuming the facial features fixated on reflect the visual information needed for making age and attractiveness judgments, it is likely that cosmetic surgical procedures targeted on the eye region, and potentially the nose region and the mouth region, may be most efficacious at enhancing one’s perceived physical appearance. acknowledgments. this research was performed in the brain and attention research laboratory, department of psychology, university of british columbia. references albert a m, ricanek k jr, patterson e, “a review of 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neuroscience – © a pion publication abstract introduction materials and methods results discussion acknowledgments references jcr hope coleman&morenofigueroa final journal for cultural research special issue on hope and feminist theory past and future perfect? beauty, affect and hope rebecca coleman and mónica moreno figueroa addresses rebecca coleman department of media, film and cultural studies, lancaster university, lancaster, la yd rebecca.coleman@lancaster.ac.uk mónica moreno figueroa school of geography, politics and sociology, newcastle university, th floor, claremont bridge building, newcastle upon tyne, uk ne ru monica.moreno-figueroa@ncl.ac.uk bios rebecca coleman is a lecturer in media and cultural studies, lancaster university. her research is primarily concerned with studying the relations between bodies and images. her book, the becoming of bodies ( ), examines these relations through empirical research with teenage girls from a deleuzian perspective and she is currently writing a book, provisionally entitled material images, which explores theories of looking, affect, and the screen in the context of contemporary popular culture. mÓnica g. moreno figueroa is a lecturer in sociology at newcastle university in the school of geography, politics and sociology. she completed a phd in sociology at goldsmiths, university of london. mónica has taught at goldsmiths and birkbeck college, university of london, and at the university of nottingham. her research has been concerned with contemporary practices of racism, mestizaje, feminist theory, embodiment, visibility and emotions. she has published in the journal of intercultural studies and history of the human sciences as well as in the edited collections raza, etnicidad y sexualidades and the forthcoming cultures of colour by berghahn books. abstract this article engages with and draws on what have been called two recent ‘turns’ in feminist theory: to beauty and to affect. while much feminist research has concentrated on the beauty industry, where beauty is conceived as a series of economic, social and cultural practices, we suggest that beauty should also be understood as an embodied affective process. our focus is on understanding the conceptions of beauty that emerged in our own empirical work with white british girls (coleman ) and mestiza mexican women (moreno figueroa ). we suggest that for the girls and women in our research, beauty is an inclination towards a perfected temporal state which involve processes of displacement to the past and of deferral to the future. we draw on colebrook’s ( ) discussion of the relationship between feminist theory and philosophies of aesthetic beauty and on lauren berlant’s notions of ‘cruel optimism’ ( , - ) and ‘aspirational normalcy’ and argue that beauty can be seen as an aspiration to normalcy that is, simultaneously, optimistic and cruel. beauty is seemingly characterised by its inability ‘to be’ in the present and is thus positioned as temporalities that have passed or have yet to come. through these displacements and deferrals, beauty is understood as both specific and imaginary, and as promising and depressing. following on from such a conception of beauty, we make a distinction between optimism and hope and argue that while, in berlant’s terms, optimism is that which is cruel, hope might involve a different way of thinking about how beauty might be experienced in and as the present. past and future perfect? beauty, affect and hope in my life what has been most important is the issue of beauty… (paulina) [h]opefully […], all the things i don’t like just go away and it like just works out that i look really good (fay) how long have people thought about the present as having weight, being a thing disconnected from other things, an obstacle to living? (berlant , ) in a special edition of feminist theory ( ), colebrook argues in her introduction that renewed interest in the ‘question of beauty for feminist politics […] is not so much moral – is beauty good or bad for women? – but pragmatic: how is beauty defined, deployed, defended, subordinated, marked or manipulated, and how do these tactics intersect with gender and value?’ ( , ). in this paper we explore the ‘pragmatics’ of this feminist ‘return to beauty’ and explore the problem of beauty through another ‘turn’ in feminist cultural theory to affect. we argue that affect is a productive way of exploring beauty because it emphasises not only content but also process; that is, it is not only necessary to examine specific beauty practices (of make- up, hair styling, dieting and cosmetic surgery for example) but it is also important to see beauty as an embodied social, cultural and economic process. taking an approach which attends to the ways in which ‘the lure of beauty seems inescapable’ (felski , ), we suggest an understanding of beauty as hope. our interest is in exploring hope as ‘an empirical question’ (back ); as the above quotations from paulina and fay indicate, we examine how hope is attached to beauty and is experienced and understood in everyday life. our focus is on understanding the conceptions of beauty that emerged in our own empirical work with white british girls (coleman ) and mestiza mexican women (moreno figueroa ). we draw on colebrook’s ( ) discussion of the relationship between feminist theory and philosophies of aesthetic beauty and on lauren berlant’s notions of ‘cruel optimism’ ( ) and ‘aspirational normalcy’ and argue that beauty can be seen as an aspiration to normalcy that is, simultaneously, optimistic and cruel. we suggest that for the girls and women in our research, beauty is equated with a sense of perfection; beauty is an inclination towards a temporal state whereby, as fay explains, ‘all the things i don’t like just go away and it like just works out that i look really good’. in particular, we focus on the temporalities of these inclinations and suggest that the girls and women experience beauty as temporal processes of displacement to the past and of deferral to the future. beauty is expressed from the present but is not located there; beauty is seemingly characterised by its inability ‘to be’ in the present and is thus positioned as temporalities that have passed or have yet to come. through these displacements and deferrals, beauty is understood as both specific and imaginary, and as promising and depressing. following on from such a conception of beauty, we make a distinction between optimism and hope and argue that while, in berlant’s terms, optimism is that which is cruel, hope might involve a different way of thinking about how beauty might be experienced. the research we discuss here are two separate projects which address, in different ways, questions of embodiment, image and visuality. one project, by moreno figueroa ( ), focuses on the significance of the role of emotions in revealing mexican women’s lived experiences of racism and explores the importance of mestizaje (racial and cultural intermixing of spanish and american indigenous people) in relation to mexican discourses of race and nation. the other project, by coleman ( ), explores the ways in which thirteen and year old british girls experience their bodies through images and argues that bodies and images are not separable entities but rather that images make possible particular knowledges and experiences of bodies. both projects involved focus group and individual interviews and involved visual methodologies; moreno figueroa used personal photographs during life-story interviews to guide women’s telling of their lives and also to discuss the relationships between racism, bodies and visibility and explore how they see themselves and how others see them and coleman used personal photographs and magazine images to stimulate discussion and an ‘image-making session’ to produce visual, as well as verbal, experiences of bodies. while neither project enquired specifically about beauty and appearance, such issues emerged as important in the participant’s accounts. for example, the women in moreno figueroa’s research discussed beauty in terms of racialised perceptions of their bodies which are a product of cultural and historical understandings of mestizaje as a way of perfecting and ‘improving the race’ through mixing and of gendered ideas about femininity: the whiter the prettier, the darker the uglier. in addition, these women also talk about beauty in terms of emotions: mainly experiences of shame, feeling inadequate and aspiring for a normalcy that ‘should/could’ be granted by such process of proper racial mixing. for the girls in coleman’s research, beauty was alluded to in terms of what might be characterised as a general dissatisfaction with their present appearance, and a hope that they would feel better about their appearance in the future, or as a satisfaction with their present appearance and a hope that this feeling would continue into the future. it is clear then that our projects raise different understandings of and feelings towards beauty. our aim is not to suggest that the experiences of beauty discussed are equivalent or uniform but rather to draw attention to some points of connection which coalesce around ideas of temporality and to examine these connections through the notions of hope, optimism and normalcy. the article is arranged around some key themes that we see as arising in both projects: (i) the displacement of beauty to the past; (ii) the deferral of beauty to the future and; (iii) in the concluding sections, wider issues concerning the ethics of hope, beauty and temporality. in order to contextualise these themes, we first outline our argument concerning the relationship between recent work on beauty and on affect drawing on the contributions that feminist scholarship has made to understandings of the complexity of beauty. beauty, affect and inclination it is clear from paulina’s statement above and from the strong tradition of feminist scholarship surveying its various aspects, that ‘[f]or women, beauty has always mattered – in a personal way, and as an inevitable, and underlying socio-political framework, for how they operate in the world’ (brand , - ). recent feminist work has identified how approaches to beauty tend to circulate around the dichotomies of pleasure-pain, active-passive, affirmation-suffering, liberation- oppression. felski ( ) suggests that such feminist analyses have converted the ‘positive’ aspects of beauty into their more ‘negative’ counterpoints. she raises concerns about this ‘compulsion to immediately translate aesthetic surfaces into political depths’ without ‘teasing apart the multifarious socio-political meanings of texts while also crafting richer and thicker descriptions of aesthetic experience’ ( , ). questioning the arguments claiming that concerns, practices and experiences about beauty are either superfluous, ‘wrong’ and/or a source of pain, here we follow felski’s aim to engage in a feminist task that explores beauty as both ‘positive’ and ‘negative’. only in this way, she argues, ‘can we continue to reckon the political costs of being beautiful while also doing justice to the reasons why, all of us, women included, continue to seek out and take solace in beauty’ ( , ). felski’s point that beauty is both framed socially, economically and politically and experienced aesthetically is key to our conception of the relationship between hope and the girls’ and women’s understandings of beauty. in particular, felski’s argument that beauty is a ‘lure’ which ‘seems inescapable’ (felski : ) leads us to examine the relationship between beauty and hope not so much in terms of specific beauty practices or ‘body work’ (davis , gimlin ) but as an embodied affective process or inclination. colebrook’s discussion of different philosophical conceptions of aesthetics is helpful here as she draws attention to how beauty has been understood both as that which is tied to pleasure, utility and the furthering of life (as hume argued) and as that which escapes or exceeds utility and the beauty industry (as in the kantian tradition) ( , - ). both understandings of beauty, colebrook argues, are relevant for contemporary feminist work. on the one hand, seeing beauty as that which is either emerging from, or useful for, the nurturing of life enables an attention to the ways in which ‘the beautiful may have been defined through a series of gendered and sexist examples and assumptions’ ( , ) and thus to the specific ‘interests it serves and how it has been valued’ ( , ). however, ‘[o]n the other hand, the experience of the beautiful as feeling can neither be explained away nor reduced to its political uses and abuses’ ( , ). while feminist empirical sociology and cultural studies has tended to focus on beauty as an industry (for example black , craig , holliday and sanchez taylor ) we are also interested in beauty as that which cannot be contained within these practices. as a hope, beauty can be understood in terms of kant’s conception of aesthetic beauty as colebrook explains it: ‘whatever the actual experience and industry of the beautiful may be, there is also a critical capacity and imperative to discern the genesis and irreducibility of the beautiful’ ( , ). as such, for kant, ‘[t]he “aesthetic” concerns nothing more than feeling: not a feeling of the body but of the mind experiencing itself, being given a sense of its own “supersensible” power’ ( , ). the conception of beauty as feeling has resonances with what has been called ‘the affective turn’ (clough and hailey ) in (feminist) social and cultural theory (see for example ahmed , ahmed , probyn , riley , sedgwick and frank ). in particular, our understanding of affect here draws on work which patricia ticineto clough describes as engaging with ‘the line of thought from gilles deleuze and felix guattari back through baruch spinoza and henri bergson’ ( , ). according to this tradition, affect ‘refers generally to bodily capacities to affect and be affected’ and ‘is linked to the self-feeling of being alive – that is, aliveness or vitality’ ( , ). such a conception of affect – as embodied feeling – clearly connects with colebrook’s account of aesthetic beauty. our argument here is that beauty works as an affective aesthetic feeling. despite its organisation into an industry which serves a particular set of interests and gives value to specific body practices, beauty is continually sought out and taken solace in. as we have suggested then, beauty is, in berlant’s ( ) terms, a bodily ‘inclination’ or ‘tendency’. in a discussion of what she characterises as the sensual pleasures/pains of eating, sex and intelligence (or ‘smartness’), berlant argues that such ‘dense moments of sensuality’ ( , ) ‘produce something not uncomplicated or amnesiac, but something that as yet has no content, just inclination’ ( , - our emphasis)i. taking up berlant’s conception and drawing on the notions of affect and aesthetics introduced above, we want to suggest that beauty, as it emerged in our research, is such a bodily inclination; not located in anything (as content) but a process which exists as and is produced through the relations between bodies, things, memories, dreams and hopes. understood in this way, for the women and girls in our research, beauty involves a bodily inclination towards a more hopeful temporality. in this sense, and as we develop further below, hope is an embodied affect; that is, hope is the feeling that inclines towards the beautiful (where the content of what is beautiful might not yet be clear) and that provides a sense of being alive. as such an inclination, hope is a productive way of understanding how beauty is located in times other than the present. an inclination suggests that bodies are tending towards a time (and space) other than where they are presently located. in the following two sections, we unpack the discussions of beauty that emerged in our research. first, we attend to the ways beauty is experienced in the past and present and in the following section we examine the deferral of beauty to the future.ii beauty and the past central to our conception of the relationship between hope and beauty is the way in which beauty is not a ‘thing’ which can be experienced in the present but is that which is felt in different temporalities. in the research data we use here, various accounts of appearance, the body and beauty emerged in relationships with the past. for example, some of the participants in coleman’s research indicated how moving to a new school and becoming a teenager had focused their and other’s attention on their appearance: fay: […] it’s sort of like secondary school really because before that you know you’re just happy cos things like [appearance] don’t matter, just happy playing and being a child, you know now […] you meet new people and new attitudes towards you that you never really experienced before […] and it’s like different attitudes and different ways of looking at yourself i think when you come up here in this extract, fay discusses her present as a time when things like appearance ‘matter’ in contrast to her explanation of her past as a time when she was ‘happy’, ‘just enjoying being a kid’. fay links being at secondary school, ‘different attitudes and different ways of looking at yourself’ and not being happy any more. while she does not describe her present as being unhappy, she does point to the difficulty of being happy because she is unaware of her body and her appearance. whereas in fay’s past happiness was unconnected from her body and appearance, a condition of being happy in her present necessarily involves what she looks like. anna, also makes links between beginning secondary school and ‘bothering’ about her appearance: beckie: so do you think the way you feel now, is that new, or have you always been sort of feeling like that? anna: i never was really bothered about what i used to look like until […] secondary school, i think that puts a lot of pressure on, and year and were always what i looked like, year i sort of think, sort of stopped and thought well hey, it’s my life it’s no-one else’s so i can look like what i want to look like and it’s not, erm, what’s the word, it’s me, it’s no-one else, i’ve got to control it to make myself happy beckie: ok, and do you think, are you succeeding in that or is it hard? anna: well yeah cos whenever you think you feel good, someone always puts you down beckie: really? and is that in school or out of school? anna: anywhere really, people do put you down, even if you think they might just be looking at you cos they think you look ok but you think they’re putting you down, cos sometimes you look at someone you think looks nice but then people think you’re looking at them saying they look horrible or something again here we see a present in which happiness has become bound up with anna’s appearance. anna explains that this ‘puts a lot of pressure on’ which she is currently trying to ‘control […] to make myself happy’. however, this is difficult to achieve as while she may ‘feel good’ about what she looks like, other people’s gazes are interpreted as about her being seen as ‘horrible’. there are clearly many issues that could be unpacked from fay’s and anna’s comments concerning the role of adolescence, secondary school, the gendered gaze and what seems to be the increasing visibility of their bodies through a focus on appearance (see coleman , moreno figueroa ). what we are interested in here are the temporalities of beauty (in terms of the girls’ appearance, how they think they look and how they think others think they look). while neither fay nor anna describe themselves as beautiful in the past, they do depict their pasts as happier, at least in part because they were not ‘bothered’ about their looks. there is, then, an inclination to beauty in the past. in contrast to the accounts above, some of the women who participated in moreno figueroa’s research raised issues about the concern with beauty in relation to both the past and present. here, then, the case of patricia illustrates the relevance of beauty and appearance across different temporalities: patricia: i feel insecure because of how i look. i mean my problem is that. so i remember in the nursery i was happy and everything, but i was kind of shy because of how i looked, can you imagine? whereas fay and anna describe insecurity in their presents but not their pasts, patricia’s memories of her past are already tempered with insecurity and a particular sense of her body. there is a part of patricia’s account which complements fay’s and anna’s explanation of their pasts as a time when they are just happy ‘being a child’. however, patricia also points to shyness and lack of confidence in her past, when she was a child, in clear reference to the appearance of her body: there has never been a time that she can remember when she was not aware of, nor unconcerned with, her body. it is important to note at this point that patricia is discussing her bodily appearance in the context of research on experiences of mestizaje and racism and it is her ‘racialised’ appearance that she is highlighting as producing her insecurity. the experience that patricia describes and the narrative produced are framed through the research questions so we cannot be sure what kind of narratives would have emerged had she just been asked to reflect on her time in the nursery. would she, for example, just talk about the ‘happy and everything’ part of her account or would the ‘racialisation’ of appearance inevitably emerge? however, in the account that patricia does give, it is clear that her past is marked by how she looks and she implies her appearance is somehow not pleasant, perhaps not beautiful or not beautiful enough. this points towards a possible distinction between what aspects of the body matter and when they do so. so while perhaps the issue of beauty did not matter in patricia’s childhood, a sense of what a racialised body ‘is like’ and ‘feels like’ was already evident. patricia’s inclination to beauty is complex; while the lure of beauty is inescapable – how she looks is of central importance – there is no sense of what felski terms ‘solace’ in the past. in other parts of patricia’s interview the relevance of skin colour is emphasised: patricia: this is my little cousin […] me and her were the same age, maybe a month apart, but i never managed to make friends with her, because, well, the barrier […] was our physical appearance. i wasn’t […] the colour […] - i mean the power of all this is incredible - because my colour prevented me from relating with my family. i don’t get on with them at all […] and when i’m with them, i feel very uncomfortable, i feel very inferior patricia’s description of her past and present ‘uncomfortable’ relationships with her cousin and her family more widely, where she ‘feel[s] very inferior’, is founded upon ‘the barrier’ of her skin colour and a sense of subordination and deficiency. she is aware of her position out of the boundaries of familial normality where the rules of a racialised beauty are clearly in operation. in her discussion of racially and sexually marked and unmarked bodies, peggy phelan argues that when trying to understand the basis for distinctions between ‘blackness’ and ‘whiteness’ (or in the mexican case, between ‘indigenous’, ‘mestizas’ or ‘güeras’iii), ‘the focus on the skin as the visible marker of race’ ( , ) and a key criteria for understandings of beauty (at least in the mexican case) becomes significant. whilst skin colour cannot contain all the possible meanings of ‘race’, it does become a crucial filtering surface that marks the body, as patricia points out, indicating that she has a different relationship to appearance and temporality than fay and anna, and therefore, a different relationship to the hope that beauty might involve. while patricia is inclined to beauty, in the sense that she places her appearance as central to her happiness, her present is no more hopeful regarding beauty than fay’s and anna’s; ‘i feel insecure because of how i look. i mean my problem is that’. although patricia’s comments are characterised by ‘racial’ marking through skin colour and the impossibility of being unaware of her bodily appearance, there are other accounts in moreno figueroa ( )’s work pointing to a different experience. consider, for example, paulina’s comments on when she was most happy: paulina: for me, going to the u.s. was huge, very liberating, i was so happy. it was great not to be with my family. […] so then, going to live there, to prove myself that i could do things on my own, that i could do a ph.d. […] because for good or bad, my identity never was […] i never was the pretty one, nor the seductive one, or something like that, my little space in life was to be the clever one and dedicate myself to academia, but even in that area i had lots of insecurities and lack of self-esteem. so then for me to be able to do the phd was really important. in this extract, paulina explains that her most liberating and ‘happy’ time in the past was moving to the united states to study for a ph.d. and ‘to prove to myself that i could do things on my own’. part of the reason for this liberation and happiness, she suggests, was that ‘dedicat[ing] myself to academia’ was ‘my little space in life’. what is interesting here is how paulina implies that an academic identity is distinct from being ‘the pretty one’ or ‘the seductive one’. to be ‘the clever one’, according to paulina, is to not have to construct her identity through her bodily appearance. indeed, while she implies that her insecurity about her appearance remains, she explains that the importance of completing a ph.d. was in overcoming such insecurities: ‘even in that area i had lots of insecurities and lack of self-esteem’. for paulina, then, academia is used as that ‘little space in life’, a space of normality where she can be ‘clever’ and where she believes her body and its appearance, somehow, does not matter. what seems to us to emerge from these very different accounts is that beauty in the present is a difficult, if not impossible, experience. while there are different ways the girls and women recognise and (attempt to) ‘control’ the importance of beauty in their presents (by constructing an identity which is distinct from beauty, by thinking ‘well hey, it’s my life it’s no-one else’s so i can look like what i want to look like’, or by identifying different ‘attitudes’ and ‘barriers’), and there are crucial differences in the experiences of beauty in their pasts, the inclination to beauty, the inescapable lure of beauty, is ever present. in the following section we examine how the inclination to beauty involves a deferral to the future. beauty and the future beckie: do ever kind of imagine your body and yourself in the future at all? fay: yeah sometimes, i just think what i’ll be like when i grow up beckie: and what would that be like? fay: just hopefully it, all the things i don’t like just go away and it like just works out that i look really good beckie: ok, so what would it look like in the future? fay: well, you’ve got to have the right figure and everything, that i won’t, sort of, all the stuff that comes with being a teenager, like spots and that, all that goes away, and i think that’s about it really, just like the figure really and i think skin in this extract taken from one of coleman’s individual interviews, fay describes her future as when ‘it like just works out that i look really good’. according to fay here, then, the future is a time of perfection, a time that she can look forward to ‘hopefully’. the future that fay describes is one that is imagined through looks and appearance. that is, in imagining herself ‘grow[n] up’, fay understands her ‘body’ and ‘self’ in the future through what she looks like. this lens of appearance through which the body is imagined in the future is key to our argument here. we want to suggest that, for the girls and women whose comments are explored in this section, the future is perfect, a time of beauty, or, at least, a temporality that is more beautiful than the present. the links that fay makes between the present and the future are important to consider. fay describes the future as a time that is in some ways disconnected from how she understands her body in the present; ‘all the things i don’t like just go away’. indeed, later on in the interview fay goes on to comment explicitly on how her future is connected to her present: beckie: so how does that relate to how you feel about your body now? fay: well, it’s what i wanna change now, what’s wrong with me now and what i want to change and i don’t know i suppose it’s only over the last few years i’ve started feeling insecure about myself, i mean i don’t remember being little and thinking ‘oh you know’, so i just hope those insecurities and stuff go away beckie: ok, so how you feel about your body now, is that better or worse than how you used to feel about your body? fay: probably worse than how i used to feel cos i never used to, even if there were things wrong with me, i never used to think they were wrong with me so it’s worse now i am aware of it, but then in a way, i don’t know, in a way it’s better cos you know that at least you can try and sort it out or whatever, that you weren’t walking round looking stupid or whatever in considering the relations between her present and future, fay highlights the insecurities she has about her body in the present and points to how her imagination of the future involves ‘what’s wrong with me now and what i want to change’. we can take from this that for fay, her present body is impossible to sustain as an imagination into the future. fay cannot imagine her present body in the future but instead conceives a body that is changed, that looks different. in making this comparison between her present body and future body, fay refers to her past: ‘i don’t remember being little and thinking “oh you know”’. as we suggested in the previous section, the past is understood here as a time when fay was unaware of ‘what’s wrong’ with her body and could be happy, whereas the present is understood as a time when fay is too well aware of her body, and is insecure about her body because of this awareness. the present is also a time when fay is aware of her possibilities of action: a time when it is possible to intervene ‘cos you know that at least you can try and sort it out or whatever’. the present is thought of as a platform for the happy future and such a platform is hopeful and embraced in terms of what can be done in it. the present is the time where the body can, hopefully, be changed in order to be possible in the future. for paulina, the present is also seen as a time which is in some way not as bearable as the future might be. however, whereas fay describes being unaware of (the problems with) her body in her past, paulina discusses how she was constantly made aware of her body in the past: paulina: in my life what has been most important is the issue of beauty, because i always say, joking, that i’m the daughter and the mother of the beautiful ones. my mother had the kind of beauty that could stop a train, and it’s not that my sister and i are ugly, but just ordinary.... for example when i was a kid, the neighbours would say things like: ‘oh these girls, with such an attractive mother’, so my sister and i grew up with that, but when my daughter was born, you know what people would say to me? ‘oh, so beautiful!’ then they would turn, look at me, and say: ‘she must be exactly like her father!’ and i used to think: ‘why they don’t say: what a beautiful girl and that’s it?’ do you know what i mean? it was a terrible thing, and i grew up with those issues, i don’t think that i’m ugly, but i always carry the ambivalence of what feminine beauty is about and that undoubtedly is something… my sister even had a nose job and me, just a while ago, i had a photograph taken in canada, i was also thinking of having a nose job too. in this extract paulina places herself in-between her mother and her daughter; she is, in some ways, a present between a past (her mother) and a future (her daughter). this past and future is understood through beauty as paulina describes both her mother and her daughter as beautiful. in contrast to the past and future, her mother and her daughter, paulina describes herself as ‘not ugly, just ordinary’. she describes how she is, and has been made to be, aware of herself as not beautiful, as being somehow problematic to the flow between the past and future. this is not just a present situation, as with for fay, as the ‘ordinariness’ of paulina’s body has been marked out for her in the past; ‘oh these girls, with such an attractive mother’. with comments such as these, it is as if paulina is pointing to how her mother and daughter are described as beautiful as unviable options for her; paulina and her sister grow up knowing that people will not say of them when they are older, ‘oh, so beautiful!’ however, despite this non-beautiful past and present, the way in which paulina imagines her body in the future is interesting because, through ‘thinking of having a nose job’, she invests some hope in a more beautiful future. in contrast to fay who sees her future as one where what is wrong with her body ‘just go[es] away’, paulina sees the future as one where what’s wrong can be made to go away. in line with our interest in points of connection rather than differentiation between our research projects, it is not our intention here to engage in a discussion which grounds the versions held of the futures by the teenage girls in coleman’s research and the women in moreno figueroa’s research in their age; we do not, for example, mean to do a comparative study and argue that it is because paulina is older than fay that she is ‘wiser’ about what the future might hold and how the future may be controlled through making things happen. what we are interested in is how for both paulina and fay there is hopefulness for the future, understood through the possibilities of being beautiful. taking up their comments, then, we want to think about hope and optimism as processes which seem indicative of the complicated and conflicting problem of beauty for feminist theory. drawing on our explanation of affect not as things but as inclinations, we suggest here that, through beauty and embodiment, fay and paulina are inclined towards the future in a hopeful and/or optimistic wayiv. that is, despite the insecurity, the ordinariness, the problem of the present, what they might or might not do to their bodies in the present, the future is hoped for as a better – more beautiful – time. in a similar way, catherine and tina, participants in coleman’s research, are also inclined towards the future which they see as a happier time. more specifically, they explicitly draw attention to the relationship between hope, optimism, normalcy and beauty: beckie: so in the future your body will be, you’ll be happier with it? catherine: yeah, happier beckie: what do you think? tina: i don’t know, it depends whether i get taller and like stuff, if i stay this height then i’m just gonna be that little fat girl but if i get taller then i think it’ll be better catherine and tina present here a case that being happier with their bodies is closely linked with beauty and its implied parameters of normalcy (being taller for example). however, what is interesting here is that their image of this happier future is somewhat vague. the relations between this point in the present (of being, in tina’s words, ‘that little fat girl’) and the future that will ‘be better’ are imprecise and not straightforward. there is no sense of how such a future will be achieved. instead, the future is a temporality which is inclined towards; not as a particular content nor through a specific set of practices, but rather through a feeling that ‘it will be better’. such a vague image of the future, or such a feeling that it just will be better, is also what seems to be at stake in fay’s and paulina’s descriptions of a better, more beautiful and more normal, future: ‘the right figure’, ‘skin’, a different nose. it is perhaps mistaken to suggest that fay, tina, catherine and paulina do not have more precise notions of what will make them beautiful and how they will achieve beauty that were not expressed in their interviews. it would also be mistaken to suggest that simply by having precise notions of beauty and plans to become beautiful the relations between the present and future are straightforward. however, what we are interested in here is how beauty is understood as something that is not possible in the present but might be possible in the future. beauty, optimism and hope so far we have suggested that the ‘lure’ of beauty, for the girls and women discussed above, involves a temporal displacement to the past or deferral to the future. we have argued that an attention to beauty not only as specific practices but also as a bodily inclination is crucial in order to explore what felski, among others, has identified as the contradictions inherent in contemporary understandings and experiences of beauty. indeed, as colebrook proposes, both philosophical accounts of aesthetic beauty that emphasise how ‘the beautiful may have been defined through a series of gendered and sexist examples and assumptions’ ( , ) and those that see beauty as feeling, irreducible to utility and industry, are necessary for feminist theory. to explore the relationship between beauty and hope further, we want to take up these different conceptions of aesthetic beauty and map them on to the ways in which we see both optimism and hope as important to understanding the experiences of beauty that emerged in our research. berlant’s notion of inclination, on which we have drawn so far, can be helpfully considered in relation to two other of her concepts; ‘cruel optimism’ ( ) and ‘aspirational normalcy’ ( ). berlant defines the latter concept as ‘a desire to feel normal and to feel normalcy as a ground of dependable life, a life that does not have to keep being reinvented’ ( , ). normalcy is a position which is not derided but desired by those who do not have access to it. berlant’s focus on normalcy is interesting for our argument here given how feminist work on beauty has identified ‘feeling normal’ as a key impetus for women’s decisions to have cosmetic surgery (davis ) and to engage in bodily practices including dieting, exercise and beauty treatments (gimlin ). drawing on this work, then, we can partly understand the girls’ and women’s inclinations to the past and the future as an aspiration to feel normal. feeling normal in the cases we have discussed might involve feeling as if their looks were unimportant (as with fay’s and anna’s inclination to the past, for example, or with paulina’s identification with academia), feeling as if in the future they will look more beautiful (as in the case of fay, paulina, catherine and tina’s experiences discussed in the previous section) or feeling as if skin colour and bodily appearance did not matter in a racist culture (as with patricia as an example of the women who participated in moreno figueroa’s research). as we suggest that beauty works as a lure through which bodies are inclined to a past or future temporality, we think it is significant to examine how the present temporalities of the girls and women are difficult. that is, the aspiration to normalcy in the past or future involves an attachment that both offers promise and entails cruelty and compromise. to understand this we turn to berlant’s concept of ‘cruel optimism’ which refers both to an ‘attachment’ to ‘compromised conditions of possibility’ and to how this attachment produces ‘something of the continuity of the subject’s sense of what it means to keep on living on and to look forward to being in the world’ ( , ). berlant’s cruel optimism, then, is not so much concerned with the content of the attachment (with what the attachment is or is to) as with what the attachment itself makes possible; an ability – a compromised ability – to live on and to look forward to being in the world. here we can conceive the girls’ and women’s present in terms of such a cruel optimism; in displacing beauty to the past or the future there is a promise that it is possible to ‘keep on living’ and, at the same time, a compromise of what ‘being in the world’ involves. exploring beauty through the concept of cruel optimism, then, helps us to account for both the ‘positive’ and ‘negative’ aspects of beauty as conceived in feminist theory and in philosophies of aesthetics. it indicates how the bodily inclination towards beauty enables the ability to keep on living on. and, at the same time, through its attachment to a condition of possibility that is not in the interests of those bodies, such a bodily inclination towards beauty necessarily compromises that ability to keep on living on. taking up berlant’s argument here, we can conceive the understandings of beauty that emerge in our research as an attachment which makes possible a difficult (unbeautiful) present through a displacement or deferral to the past or future. according to such an approach, the attachment to beauty is simultaneously a compromised condition of possibility and a means of making this compromised condition bearable. that is, by attaching to beauty, girls and women both limit their conditions of possibility (for example by experiencing the present as difficult) and live and look forward to extended conditions of possibility and normalcy (‘when i was/am beautiful, life was/will be better’). cruel optimism, then, necessarily involves a difficult present. that is, optimism is an attachment to a past or future temporality, and it is this attachment that makes the present both difficult and bearable. in this sense, the optimism of berlant is closer to the conception of hope that ghasson hage ( ) proposes, than the one we will propose here. for hage, according to capitalist values and interests, hope is opposed to joy; ‘[i]nstead of living an ethic of joy, we live an ethic of hope, and that becomes an ethic of deferring joy which fits in very much with the idea of saving and deferring gratification’ ( : ). indeed, berlant explains the concept of cruel optimism through three examples ‘of the suspension of the reproduction of habituated or normative life. these suspensions open up the “impasse” as a name for the transitional moment between a habituated life and all of its others’( , ) and render the normative, disappointing rhythm of life clear. the present, as suspension, thus takes on an impossibility and berlant asks, ‘how long have people thought about the present as having weight, being a thing disconnected from other things, an obstacle to living?’ ( , ) in berlant’s terms, we can understand the present for the girls and women involved in our research, as an obstacle to living through the suspension or deferral of beauty to a different temporality. understood through cruel optimism then, the present in its difficulty is both ‘disconnected from other things’ and attached to an other temporality. however, for us, the question remains of whether such an understanding of beauty accounts for all of what is being explained in the extracts above. can the inclination to beauty be captured completely with the concept of cruel optimism? it is in this sense that we would like to introduce a notion of hope in contrast to the conception of optimism drawn on here. while for berlant optimism is necessarily cruel and while for hage the ‘ethic of hope’ is the deferral of joy, we suggest an alternative notion of hope, as that which is, or which might be, detached from deferral and compromise and which is, instead, closer to the aesthetic attention to beauty as feeling. of course, we are not suggesting that such a notion of hope is what is ‘really’ at work in the experiences of beauty discussed above. not are we suggesting that the bodily inclination to beauty is outside of gendered and sexist interests and values; it is necessary, as both berlant ( ) and hage ( ) argue, for a critique of political economy to run ‘alongside’ a feminist analysis of beauty. however, we propose a notion of hope in order to focus attention on how, as colebrook puts it, ‘hope is structural to feminism’ and this hope ‘maps out some future that is at once other than the present and yet referenced to an unfulfilled actuality of the present’ (colebrook: this volume). if hope for a future which is ‘other’ to the present is ‘structural to feminism’, is there a way of thinking differently – more hopefully – about the experience of beauty? what is the ‘unfulfilled actuality of the present’ that might make this different future possible? one way of thinking this through is in relation to patricia’s practice of looking at and commenting on her photographs in her interview with moreno figueroa ( ). while we have discussed above how patricia explored painful and difficult memories and experiences where the links between race, racism and beauty are in operation, she also described how looking at her photographs, as she was in her past but also while she was being interviewed, could produce different feelings: patricia: i also like this photograph very much. i used to like myself, and i used to like looking at myself as a child. i used to like looking at myself and taking out these photographs, to raise my self-esteem. i used to say: “look how nice, look, i'm beautiful”. didn’t i? these photographs cheered me up because i felt uncomfortable with myself but when i saw these photographs i used to say, “hey! but i'm not that ugly”. i saw them many times and with that intention, maybe i was or years old, and i said to myself: “hey! but i'm not that ugly”. what can possibly have made me feel like that? i felt one way and then i saw myself another way. i liked my photographs... but there was that contradiction... that's why i’m showing them to you. here, then, patricia explains how, looking back, she can see that, in contrast to her memories, ‘i’m not that ugly’. for patricia, seeing the contradictions of ‘feeling beauty’ – ‘i felt one way but then i saw myself another way’ – ‘rais[ed] my self- esteem’. in terms of our argument here, such a practice might be termed a return to and a recognition of the unfulfilled actuality of the present; a means of challenging the difficult present by re-experiencing the past. we suggest that this practice constitutes not so much ‘cruel optimism’ but hope as an ‘empirical question’, tied to everyday practices of ‘living on’ which are inclined to changing life for the better. furthermore, patricia’s practice indicates, we think, hope for not only a better future (as the concepts of cruel optimism and aspirational normalcy suggest) but for a better present. it is not that patricia completely re-invents her past (as discussed above it involves pain) but rather that what is unfulfilled about the past (‘i’m not that ugly’) is re-visited and re-experienced; is brought into the present. patricia’s present is not ‘suspended’ through an attachment to other temporalities but rather is being felt differently, at least in part, as it is lived. in this way, our ‘sense’ of hope can be conceived in terms of what hage describes as ‘the ethic of joy’. hage summarises spinoza’s notion of joy as follows: for spinoza, joy comes from a simple change to the better in the state of the body. that is, it is an experience of reaching a higher state in the capacities to act, associate and deploy oneself in or with one’s environment which constitutes us as a specific “thing” in spinoza’s language. so joy is not the experience of a static state of being, no matter how “high” that state is. joy is the experience of a growth from one state of being to a more efficient one as it is happening. it is the experience of that quantum leap of the body, of the self as it is moving into a higher capacity to act (hage : ). hage’s account of spinoza’s conception of joy is significant because of its emphasis on the experience of change or movement as it is happening (‘i’m not that ugly’). that is, in contrast to the ‘optimism’ that is involved in and produced through the movement from a difficult present to a better – more beautiful – past or future, joy here can be understood as a temporal experience that folds the past, present and future into each other and experiences the becoming better not in an other temporality but now, in the present. this resonates with the notion of aesthetic beauty as feeling, ‘not a feeling of the body but of the mind experiencing itself’ (colebrook : ). and, of course, it resonates with patricia’s practice whereby she is able to find beauty not only in an other temporality but also, in part, in her present re-experience of the past. our argument that, in the context of experiences of beauty, hope should be conceived in terms of this ethic of joy is thus part of a desire to shift the experience of beauty away from an always-already other temporality and into the present. this would be to address, in berlant’s terms, the ‘weight of the present’ and to ‘interfere with varieties of immiseration’ rather than to ‘ride the wave of the system of attachment that [we] are used to’(berlant , ) . to draw on hage’s argument, if not his vocabulary, it would be to develop an ‘ethics of hope’ which challenges the ethic of (cruel) optimism characteristic of western capitalism in general, and of the girls and women’s experiences of beauty in particular. it would be to see hope as embedded in present daily practices as an unfulfilled actuality that might be exploited in, by and for feminist theory. acknowledgements we would like to thank sara ahmed for the very helpful comments she made a long time ago on a much earlier version of this argument. they were instructive in our thinking about the article that is printed here. we would also like to thank the two anonymous reviewers for their constructive feedback. bibliography ahmed, sara ( ) 'communities that feel: intensity, difference and attachment' in a. koivunen & paasonen, s. affective encounters: rethinking embodiment in feminist media studies. 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( ) body work: beauty and self image in american culture (berkeley and los angeles: university of california press). hage, ghassan ( ) ''on the side of life' - joy and the capacity of being - with ghassan hage' in m. zournazi (ed.) hope: new philosophies for change (london: lawrence & wishart); - . holliday, ruth & jacqueline sanchez taylor ( ) 'aesthetic surgery as false beauty', feminist theory, ( ); - . moreno figueroa, monica ( ) the complexities of the visible: mexican women experiences of racism, mestizaje and national identity, unpublished phd thesis, goldsmiths college, university of london. phelan, peggy ( ) unmarked: the politics of performance (london: routledge). probyn, elspeth ( ) blush: faces of shame (minneapolis and london: university of minnesota press). riley, denise ( ) impersonal passion : language as affect (durham, n.c.: duke university press). sedgwick, eve kosofsky & adam frank ( ) touching feeling: affect, pedagogy, performativity (durham: duke university press). notes i berlant’s discussion is focused on mary gaitskill’s ( ) novel two girls, fat and thin. ii in explaining beauty as an affective inclination away from the present, our intention is not to suggest that time is some kind of linear advancement that underlies a body (it is not, for example, that bodies progress from or to beauty) but rather that we understand beauty as attachments to or dispositions towards specific temporalities (‘the past’ and ‘the future’). temporality is in this sense a process: not something that is containable (an object) nor that develops in a logical, progressive fashion, but rather a dynamic condition through which bodies incline, in this case, to beauty. iii güera is an adjective use to describe somebody who is perceived either as having white or whiter than skin colour or blond or light brown hair colour. it can be said of the fairest person in a given group, i.e. the family. iv in saying that there is an inclination towards the future we are not saying that the future is an object that can be aimed for. rather, what we mean is that future is a temporal condition, different to the present. as a condition, the future is also prospective, meaning that it looks forward or is looked forward to: expected, hoped for. knowledge of beauty in plato's symposium author(s): ludwig c. h. chen source: the classical quarterly, new series, vol. , no. ( ), pp. - published by: cambridge university press on behalf of the classical association stable url: http://www.jstor.org/stable/ accessed: / / : your use of the jstor archive indicates your acceptance of jstor's terms and conditions of use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. jstor's terms and conditions of use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the jstor archive only for your personal, non-commercial use. please contact the publisher regarding any further use of this work. publisher contact information may be obtained at http://www.jstor.org/action/showpublisher?publishercode=cup. each copy of any part of a jstor transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. jstor is a not-for-profit organization founded in to build trusted digital archives for scholarship. we work with the scholarly community to preserve their work and the materials they rely upon, and to build a common research platform that promotes the discovery and use of these resources. for more information about jstor, please contact support@jstor.org. the classical association and cambridge university press are collaborating with jstor to digitize, preserve and extend access to the classical quarterly. http://www.jstor.org http://www.jstor.org/stable/ ?origin=jstor-pdf http://www.jstor.org/page/info/about/policies/terms.jsp http://www.jstor.org/action/showpublisher?publishercode=cup classical quarterly (i) - ( ) printed in great britain knowledge of beauty in plato's symposium i plato's symposium consists of six speeches on eros with the addition of alcibiades' praise of socrates. of these speeches socrates' speech is philosophically most important. it is true that the speech is given as a report of diotima's view on eros, but 'she is a double of the platonic socrates',' and we take her view as the theory of socrates in this dialogue. early in his speech it is asserted that eros is intermediate between wise and ignorant, beautiful and ugly (good and evil), and mortal and immortal. stripped of the mythological disguise, the lover (now a human, not the demon) is intermediate in these three cases, and strives for the knowledge of beauty, beauty itself and immortality, respectively. here are three aims in our dialogue. let the first of them be called a cognitive aim and the last two ontic aims. the three aims are not of equal importance, and their relative priority is as follows. the final goal, from the beginning to the end of socrates' speech, is beauty. in order to possess it everlastingly, there is the need to strive for immortality. it turns out that of the three forms of immortality the highest one, if it is possible for the lover, results from his creation of real virtue and not from the creation of its shadows. the latter is due to the divine gift, and the former to knowledge. hence there is the striving for the knowledge of beauty or good. to sum up, immortality is the condition of everlasting possession of beauty or good, and the knowledge of the latter is a means to the immortality possible in the highest form. the series begins with striving for the knowledge of beauty. from the interrelationship among the three aims it is seen that the cognitive aim can be treated alone with occasional reference to the two ontic aims. this is what we are going to do in the following. ii .a. a. the steps in striving for the third form of immortality are mingled with the steps of cognitive striving until the last step. the first step in both cases has beautiful bodies for its objects. the pursuer of beauty should know that beauty in all beautiful w. c. k. guthrie, a history of greek philosophy iv (cambridge, ), p. . throughout this paper by 'socrates' is meant the speaker socrates in plato's dialogues without any implication of an answer to the problem of the historical socrates. a - ; b - ; d -e . cf. w. kranz, 'diotima von mantineia', hermes ( ), ; he gives more cases which do not concern us here. the lover being intermediate in these cases does not have wisdom (knowledge of the good and, therefore, also of the beautiful) and beauty and is not immortal. hence he strives for them (cf. the general account of ero t vlev a if.), and makes an effort to possess them (cf. e - ). i.e., the possessor himself must be deathless; hence there is the striving for immortality. the three forms are immortality in the form of prolongation of the life of the race, a - b ; in the form of leaving behind oneself everlasting fame, c l- e ; in the highest form resulting from creating real virtue based upon the knowledge of beauty or good al- a . a - . ravro[a aperw created by statesmen ( d -e ) is ovre fvtel ovt? te alktov, aaaa oel[a /ioitpa rapaylyvotfevr avev vov.... (men. e - a ). philosophic virtue is based upon wisdom, as is known from earlier dialogues; see especially the last argument for the inaccurately formulated thesis that virtue is knowledge in prot. a - e . beauty in plato's symposium bodies is one and the same. but, at the beginning, the pursuer has not come as far as he will later; what he actually realizes at the present moment is only that the beauty in this body is akin (adelphon) to the beauty in that body.' the beauties in these bodies are not a single beauty and the beautiful bodies are also different bodies, as is seen in the case of twins. the lover concentrates on the fact that this body has the same quality as that body; the object of his knowledge is really this or that beautiful body as deindividualized, i.e., without regard for its possessor (e.g., alcibiades, charmides). consequently, he loves all these bodies indifferently, not the beauty-in-all-bodies as such. next comes the beauty in souls. he regards it as higher in value than the beauty in bodies. yet what he loves is the beautiful souls of young men and not the beauty-in-all-souls as such, because he creates beautiful discourses to improve these youths in virtue, i.e., to make their beautiful souls more beautiful, not the supposed identical beauty within the 'level' of beautiful souls. hence what the lover has in mind is still beautiful instances. next to beautiful souls are beautiful institutions and laws. the same thing happens b . ev te ka trarvtv. . .to ml trarov troi aoulaal kcaaaos is what the lover should know b - , but what he at present actually thinks is ot rt kaaaos tro rt orctovv acuoiat tr) re tl etepp awuiatl a ,ea qv octl a -b . i take tovto in b as referring to a -b not to b - , the latter being inserted as a parenthesis to explain what the pursuer of to crx' elset kaao,v should know, not what he at present does. if it refers to b - , it is in conflict with avyyeves in c and rtve& in b . 'akin' is jowett's translation of a ea ov; more exact is schleiermacher's' verschwistert' in german; cf. also robin's translation into french: 'soeur [de la beaute]' (le banquet (assoc. bude), paris, , p. ). j. m. e. moravcsik, 'reason and eros in the "ascent s-passage of the symposium', in anton and kustos, essays in ancient greek philosophy (albany, n.y., ), pp. - , finds his pattern of r-steps in 'first, reasoning recognizing common features of a plurality of instances, and isolating the common element and grasping its unity'. after quoting r. g. bury, the symposium of plato (cambridge, nd ed. ), p. xlii, he continues: 'it is crucial to note, however, that... the relation between unities on any given plane and their instances is not the only " one and many" relation described in the passage. for in addition to seeing the unity within each level, the mind has to grasp that all the levels are "akin"; they are, one might say, species of beauty.' though moravcsik emphasizes the second relation (to which we shall return; see n. ), for the moment we shall concentrate on the first point - which he takes for granted. he finds a 'unity within each level'. this supposed unity is questionable. in his rl, , the lover recognizes only that the relation among the instances is daea,ov. even twin brothers are not a single person and their characteristics, though similar, are not a single characteristic; no matter how much they are like each other, their relation is not one of identity. there is no unity to replace a ?ea ov elvai. the lover realizes no more than this 'verschwistertsein' among beautiful bodies; he does not realize the beauty as such in all beautiful bodies. otherwise he would love one and the same kaaaos cmr nraatv roig acwucaac instead of karaatrivai rtcvrwv trcv kaa,v a a-rcowv epaarrbv ( b - ). one may compare the laches: when the general has been made to understand the nature of the question, he gives a definition of courage as such, not of its instances distributively ( b -c ). to return to our dialogue, when the lover advances to love beautiful institutions and laws, he still grasps only their avyyevela ( c - ) and not the yevos; being avyyeve is not the same as being one and the same genus. b - . i take the word 'deindividualize' from robin, op. cit., xciii, although he uses the word differently. for deindividualization, cf. t. gould, platonic love (london, ), p. , who, without having this concept in mind, yet rightly says about this fact: 'and actually [we] quite forget the individual who first quickened our awareness.' b -c . since this passage comes between the passage on beautiful bodies and the passage on beautiful institutions and laws, to ev trais vxaig ka,aaos is to be understood as parallel to aeasc ov and avyyevce in the other two passages. it is not the supposed unity within 'level' of beautiful souls. for robin's interpretation see below, n. . to the lover as before; he sees that the beauty in them is of one family (syggenes), but he does not grasp the genus itself.' the last group of beautiful objects to which he is led is the sciences. his knowledge here still does not go beyond instances, namely, single beautiful sciences. this is testified to by the metaphorical expression 'the vast sea of the beautiful'. the objects of all these groups are particular instances of beauty. the lover's knowledge expands from one group of beautiful objects to another group horizontally. it moves in the sphere of particulars, in the part of the realm of being which is, so to speak, flat and without tiers. /. the lover - or more exactly in terms of his cognitive striving thephilosophos - who has progressed this far must stop and not proceed for a while. he must wait until he has been strengthened and grows by contemplating the vast sea of beautiful instances. then he will suddenly behold the beauty itself which is beautiful. b. two words are important here: 'until' (heos) and 'suddenly' (exaiphnes). by paraphrasing them we may elucidate the whole method of apprehending the idea of beauty. the expansion of knowledge from one group of beautiful instances to another group occurs smoothly and gradually; there is no need to wait for anything before taking the next step. but having reached the group of beautiful sciences the philosophos has to wait before proceeding further. this indicates that the transition from knowledge which has reached this point to the beholding of the idea is different in nature from the previous successive expansions from knowledge of one group to knowledge of another group. this transition, not the foregoing process of expansion, is the ascent proper. c avyyeves; cf. above, n. . c - . moravcsik, op. cit., - , stresses this 'level', the group of beautiful sciences or r& kaaa ikaorptara, and distinguishes correctly between sciences and bodies: 'the instances of science are themselves already on the plane of the abstract and general', whereas instances of bodies are not. however, he misses the point in the discussion. the topic is the striving for beauty through the love of beautiful instances. socrates' speech in this section starts from rta kaaa awatraa a . they are relevant instances only when our attention is focused on their being kaaad, not on their being odu ara. beautiful bodies without regard for their being beautiful are not instances of beauty, but of body; as instances of body, they are irrelevant to the topic. it is similar with beautiful souls, beautiful institutions and laws, and beautiful sciences. though beautiful sciences qua sciences have a different ontic status from beautiful bodies qua bodies, in regard to their being beautiful they are particular instances of beauty and thus strictly parallel to beautiful bodies, which, qua being beautiful, are also particular instances of beauty. the section deals with beauty and its instances, not body and its instances, and equally not science and its instances. beautiful bodies qua bodies and beautiful sciences qua sciences are equally irrelevant here. so far as they are relevant, they are regarded as particular instances of beauty. this is why all of them are designated rta ra ko.aaa. (see the passage given below in n. .) d . this can refer to nothing else but the great quantity of instances in which beauty itself is instanced, as is clear from the recapitulation. see the next note. all of these objects of knowledge are designated in the recapitulation b -d equally ta e, rde tra kaaad in contrast to eke?vo to kaaoxv (cf. e - ; the same contrast is there) which the lover has not come to behold yet. d -el, el- . pajcets kal av'roqels is a biological metaphor, which can be best understood from the passages on nourishing in the phaedo ( b ) and the phaedrus ( d - and b -c ). we may paraphrase the same metaphor in the three dialogues in the following way: when the soul cognizes, it is in the state of cognition. the more it cognizes, the richer becomes its cognitive content. in this sense the soul is nourished and grows in cognition by the object it cognizes. we may neglect the differences in these passages for the present. scholars usually speak of the ascent in terms like 'the "ascent" - passage in symposium'. exactly where the ascent is should be determined by a careful examination of the text. from e - a c rl is used with a verb of motion or as a prefix for a compound verb of motion a total of twelve times. (we disregard it when used neither with a verb nor as a prefix of a l. c. h. chen beauty in plato's symposium between the particular instances and the idea of beauty there is a hiatus. the process of horizontal expansion cannot cross it and has to stop for a period during which the mind is intellectually strengthened by contemplating the vast sea of deindividualized instances which are all akin in being beautiful. the interval lasts until the mind has grown strong enough to take suddenly the upward leap and to cross the ontic gap cognitively. this leap is indicated by 'exaiphnes'. the leap is the ascent, the ascent to the vision of the idea of beauty. the preceding process of expanding in the horizontal direction and the interval of intellectual strengthening mediately and immediately prepare the way for it. . a. scholars like to interpret this method of apprehending ideas in terms of abstraction and generalization, ' whereby they read empirical logic into plato's theory of ideas. in fact, there is neither abstraction nor generalization for plato as there is for later empiricists. the deindividualization of which we spoke above is not abstraction. what is reached by abstraction is something common, but the beautiful body deindividualized is still a particular body; it is just that its possessor is being disregarded. generalization in empirical logic produces a concept; for plato the apprehending is of an idea - in the symposium, the idea of beauty, a being, an entity, not a concept. leisegang, op. cit. col. , finds even here the dihairesis (division) of plato's later dialogues and interprets the idea of beauty reached by 'generalization' as the 'spitzenbegriff', which is divided into 'das geistige und sittliche, das seelische und korperliche schone'. moravcsik, op. cit. , understands his 'unities' as 'species or kinds of beauty'. as a matter of fact, there is in this passage of the symposium neither the generic relation anachronistically read into it by leisegang nor the' one and many' compound. such passages are found twice [ b , and ] and are irrelevant to the ascent.) the twelve cases are: ( ) a , ( ) a , ( ) c , ( ) d , ( ) b , ( ) b , ( ) c , ( ) c , ( ) c , ( ) c , ( ) c (er'), ( ) c (frt'). of these twelve cases case ( ) is taken up in case ( ). (for ~ert in these two cases, another preposition rrpo is also used at e .) they concern pursuit of eros, but not directly the ascent. of the rest, emrt in cases ( ), ( ) and ( ) is used in the same way. case ( ) is expressed more fully in ( ) and ( ). this leaves the following cases: ( ), ( ), ( ), ( ), ( ), ( ) and ( ). cases ( ), (i ) and ( ) seem to form a series of ascending steps arro t(rv kaar)v ojwluatwv ?rtl ta kaaa crtrt t evlata, alro tyrv f tt jt evuatv er t tar kaaa itaoqlmata, a to twcv !juao )daatwv etr ekeivo to rad r fa ... avtov ekeivov tov kaaov /iarotiyia c - . but in comparison with cases ( ) and ( ) atrri evog ~ri o ekat a ro' vo;v tr rr tavta ta kaaa acoata the ' rl in ( ) and ( ) cannot indicate the ascent; it refers rather to the same horizontal expansion as in ( ) and ( ). the cdr` in case ( ) should be understood from cases ( ) and ( ) because the three to 's c ( ), c ( ) and c ( ) are the enumeration of arro tr^v& and arto twrvs t(r kaa ,v which are summarily stated in b ( ) and c ( ), respectively. to sum up, in the context in question only the r t's (as preposition or as prefix) in cases ( ), ( ), and ( ) indicate the upward direction, the same upward movement to the idea of beauty. this is the only ascent in the passage under discussion. the ascent has only one step and no more, i.e., the step from beautiful instances to the idea of beauty; there is no ascent until the final step in the whole movement is taken. all the other steps in the process are steps of horizontal expansion preparing for the ascent. if this theory (which forms the ontic ground of the methodology for apprehending the idea of beauty - or rather ideas in general) is called a tier-metaphysics, then there are only two tiers, the level of ideas and the level of particulars; there is no generic hierarchy yet. e.g. w. lutoslawski, the origin and growth of plato's logic (london, ), p. , bury, op. cit., p. xliii, h. leisegang, article 'platon' in re, . xi ( ), col. . e:atsv sg karto etral t oavaactrov tr]v vwagtv kaaov e - , which is variously expressed b , c -d , - , e , - ; all of them refer to the idea of beauty. relation between the supposed unities as kinds of beauty and the idea of beauty itself assumed by moravcsik, who basically takes the relation of adelphon for identity. were there something between particular instances and the idea, the whole cognitive striving would have two major transitional points, one between the beginning and the supposed metaxy, and the other between this and the termination of the whole process. the author of the dialogue indicates only one such point and makes an effort to draw his reader's attention to the temporary stop in the lover's further proceeding before reaching the goal and his sudden attainment of it. moreover, the recapitulation of the whole process of cognitive striving ( c l-d ) is stated too definitely to allow for the possible insertion of an intermediate such as 'das geistige und sittliche, das seelische und korperliche schone', or 'unity within each level' between 'the instances of beauty' and the idea of beauty itself. b. an interpretation of a different type by an anonymous scholar should be considered here. he in fact agrees with me in rejecting that type of interpretation of which leisegang's and moravcsik's are mentioned as examples, and he concedes that 'beauties are not ranged in any genus-species hierarchy'. but in his opinion 'there does seem to be an "ascent" in value', and my 'purely horizontal approach is unnecessarily overstated'. i agree to his ascent in value but with limitation as well as more positively. in my opinion, there is such an ascent in a certain part of the horizontal expansion, and i would like to supply, for our common view, the textual evidence which he neglected for this ascent. it is explicitly stated in the text that beautiful souls are timioteron than beautiful bodies, and we may even add the designation of the latter as smikron ti in comparison with beautiful souls (and with beautiful institutions and laws, too). thus the same process from beautiful bodies to beautiful souls, or to beautiful institutions, from the ontic viewpoint is a horizontal expansion and from the viewpoint of value is an ascent. both are present in the text and neither is meant to replace the other. and the replacement is also not necessary because as the same processes looked upon from different viewpoints they do not contradict each other. then there is the question of preference of the one interpretation over the other with respect to their different approaches. let us consider the interpretation of the anonymous scholar. how far does his 'ascent in value' mount? does it carry on to pass from beautiful souls to beautiful institutions? and still further on to beautiful sciences? the text knows no value-relation either between the first two groups or between the second two groups. the ascent see n. . moravcsik takes irav in c as referring not only to all e trtrsevl'ara and v ool but to' all of the levels', because only in this sense r&iv avro clvtu , vyyeves eatv ( c - ). if by 'levels' he means (a) groups of instances, then there are no species or kinds of beauty because these groups are not species or kinds. if he means (b) his 'unities' because they are akin, then they are species or kinds of beauty. but there are no such 'unities' (see above n. ). moreover, he must take c - as a summary of his 'unities' on the preceding levels. but such a summary should wait until after the etrlt lt o)v kiaaaos c and include this as well. d -e , e - . 'turning towards the vast sea of the beautiful', which moravcsik, op. cit., - , stresses, is only a way to sum up what has been achieved and to prepare for the final step. it points to the subsequent transition. but there is no indication of the transition from the instances to the supposed 'unity within each level', neither indicated by a literary device nor implicit in the text. b and c . autlkpov nt here is a value predicate, 'of little importance'. the scholar in question may try to avoid the first of his two difficulties by following robin's interpretation of the ascent as comprising 'en tout quatre degr s: ? la beaut physique; ? la beaut morale; ? celle des connaissances; ? la connaissance de beau absolu, voir p. , n. ', op. cit., - . however, the second difficulty still remains. robin's 'ascension' is not an ascent in value. it is rather an ascent from emotions for different groups of beautiful instances to 'l'amour du savoir en general' (op. cit., xciii), though l. c. h. chen beauty in plato's symposium in value must stop with beautiful souls and cannot finally reach the goal, the idea of beauty. but the text does say the lover under the right guidance will finally reach this goal. if the scholar in question will, as he must, do justice to the text, he must change his approach from the viewpoint of value to the ontic viewpoint of horizontal expansion. his approach is then, indeed, not purely horizontal as mine is, but impure in the sense of being a mixture of value-viewpoint and ontic viewpoint. we may ask: of two interpretations which are equally good or bad in other respects, is the one which does not go forward to the goal without changing its viewpoint preferable to the one which does not switch between two toto genere different viewpoints? . a. in the philosophia, the striving for the knowledge (of beauty), the philos attains his goal, cognitively touches the beautiful itself, gains direct intellectual contact with it or a vision of it. but what is the content of his vision, or what does he apprehend of the beautiful itself? in the text there is at first a number of negations predicated of beauty; corresponding to these are then four positive predications: itself by itself, with itself, uniform, and always being. do these predicates, positive or negative, severally or collectively, tell us exclusively what beauty itself is? no, not at all. there is not one of these which cannot also belong to some other ideas among those enumerated in the phaedo. the passage in the symposium gives a general description rather than a definition of the idea of beauty; what this idea essentially is, is not stated. however, what is beheld must be much more than as given in the description. in beholding the idea of beauty the lover touches the real and creates real virtues. but his acquaintance with these four positive characteristics is not sufficient for what he will achieve. he sees more, yet this something more is not stated in the text. it is more reasonable to assume than not that he apprehends not only the common nature of ideas, but also the peculiar nature of beauty as a moral and/or aesthetic value. however, he does not define it, since to define beauty is not the purpose of the symposium. b. three points need to be noted here. a. in the phaedo both logizesthai and dianoeisthai as well as theasthai and kathoran are mentioned in the description of the pursuit of the knowledge of ideas, but they are not further distinguished. here in the symposium, there are two distinct cognitions: first, the vision of the beautiful itself, and then a sort of dianoia expressed as a general description of it. the description he distinguishes the movements before the final leap into movements from 'la beaute physique' to 'la beaute morale' and from 'la beaute morale' to 'celle des connaissances'. he does not explain how they are steps in an ascent, and in the text there is nothing which jutifies his interpretation. see n. . e - b . the four positive predicates are avrto kao' avro t.eo' avtrov t.ovot els ael ov. ade ov is mentioned twice, the first time at the beginnning of this passage. contrasted with it is change in various forms a - , and also b - . in contrast to avro kao' avrt is the relativity of different kinds a - . for ws...alaxpov, f. solmsen, 'parmenides and the description of perfect beauty', ajp ( ), , n. , is in favour of vogelin's reading. avtro ka ' avrto seems easier to understand from the phrasing in a later dialogue, soph. c kata tr v avt ov qvatv. the v'ats of tr kaaov itself is o cart kaaov c -d . in contrast to e? ' avtov is a number of r&a kaaa, particular beautiful things, in which beauty manifests itself ( a -b ). finally, for the meaning of tlovoelse', considering the passage by itself without connecting it with parmenides, i accept r. hackforth's interpretation of phaed. b (see his plato's phaedo, cambridge, , reprint new york, p. , n. ); the word 'uniform' is borrowed from his translation. iovoelt is repeated in e , which explains ateltkov in e i from the other side; atlelktov itself is the same as n a&vadtraewv aapkcbv etc., e - . c -d . aoyt'aeuoal c ; $tavoeiaota e ; oe&aoal see e ; o epezv e , a -b : kaoop&v d . consists of a number of predications, both negative and affirmative. though none of these terms from logic is found here, the difference between vision and predication is clear. the former is an instantaneous cognition; it is, so to speak, stigmatic. the latter is discursive, i.e., the mind goes from one term to another in affirmation as well as in negation when relating them. certainly, predication is not logismos, but it is an intellectual running-through, a sort of dianoia. f. direct contact, the intellectual seeing, is more important than the intellectual running-through here described. it is prior, and it is the basis of the description. just as description is discursive, so is any form of account-giving of ideas. accordingly, it is made clear that to acquire knowledge of the ideas is basically to gain direct intellectual contact with them. y. it is true that a description is not a definition. moreover, the description of the beautiful itself, as it is found here, is not even specific. but that no definition is given does not entail that it is impossible to give one. iii in this theory of cognitive striving in the symposium there is plato's answer to the question of how we come to know the beautiful itself, which is a special case of how we come to know ideas. in order to understand its significance more fully, we may compare it with the answer to the general question in the phaedo. in treating of the epistemology in the phaedo scholars pay attention usually and almost exclusively to the theory of recollection and the method of hypothesis in that dialogue; however neither of the two tells us how knowledge - or more exactly, knowledge in the primary sense - of the ideas is acquired. . a. in hypothesizing a logos concerning ideas to solve a problem, so much of their contents as directly concerned must have been known: the method of hypothesis does not acquire it, but presupposes it. this knowledge precedes the hypothesizing. how is it acquired? in the phaedo there can be no other answer than 'by recollection'. b. recollection in the case of ideas is the recalling of the knowledge once gained before our birth and then lost at the moment of our birth. from recollection we have only second-hand knowledge. then there is the question of how the original knowledge of ideas is acquired. the primary sense of acquiring knowledge of the ideas refers to acquiring the original knowledge of them. c. for the answer to this question in the phaedo, we must turn to that usually neglected part of the dialogue, the part on the genuine philosopher. the answer is pessimistic. socrates there states his fundamental belief that 'the impure is not permitted to lay hold of the pure'. from it follows the basic principle of the method: to know the pure by the pure. the object pure is auta ta pragmata, or ideas; the subject pure is the soul by itself. man is a 'composite structure of soul and body'; in this composition the soul is kneaded together with the body and 'contaminated by such an evil', hence it is impure. it is impossible for us, as the composite structures, to have knowledge of ideas when we are alive. if it is ever possible, it is only after death, i.e., see j. adam, the republic of plato, vols. (cambridge, and ), ad rep. d : 'stdvola is the general word for a state (e:ts) of mind or mode of thought in greek.' and from rep. , c we know that the intellectual 'seeing' is also the basis of reasoning. that it is the basis of defining hardly needs to be said, because definition is the formulation of the essential nature of what is intellectually seen. cl ff. a ff. e - e . a -b ; the translation is jowett's. l. c. h. chen beauty in plato's symposium when the soul is totally separated from the body and comes to be by itself. the whole life of the genuine philosopher is the practice of dying, reducing the connection with the body to the absolutely necessary, by habituating the soul to gather itself together from every part of the body so that when purified he may acquire the desired knowledge after death. . according to the theory of cognitive striving in the symposium, as seen above, the lover under the right guidance finally reaches his goal: he enjoys the vision of the beautiful itself. the contrast between the two theories in these two dialogues is too obvious to be denied. then how does this difference come about? . a. first, it comes about from the change of the point of view. in the symposium attention is paid neither to the dichotomy of life and death, nor of soul and body, and nothing is said about knowledge after death. instead, socrates focuses his attention on life alone. the pessimistic conclusion concerning acquisition of first-hand knowledge in the phaedo becomes in the symposium pointless and hence inapplicable. the success of cognitive striving will not be denied without further consideration as it would if the viewpoint in this dialogue were still the same as in the phaedo. now an account must be given of this striving from the present viewpoint; this account has a conclusion directly opposite to that in the phaedo. b. secondly, the optimistic conclusion in the symposium is due to the discovery of a new access, not found in the phaedo, to ideas, in the present case to the idea of beauty. this consists of the following three points: a. the horizontal expansion, f. the pause for strengthening the mental power for the next step and y. the final leap. a. the methodos in the symposium, like the recollection in the phaedo, starts from sense-perception. from perceiving sensible objects recollection is prompted, and it immediately revives lost knowledge, e.g., from perceiving equal sticks ensues immediately the revival of the knowledge of the idea of equality, and it ends in this second-hand knowledge. in the symposium the initial love of one particular beautiful body is expanded to the love of a second, and then to all beautiful bodies. the expansion continues horizontally from particular objects which are sensible in the proper sense through particulars which are sensible in the improper sense to particulars which are hardly sensible in any sense. in the phaedo socrates speaks of the philosopher's habituating his soul to gather itself together from the body, as far as possible, as the preparation for the acquisition of the knowledge of ideas after death, but we are there not told in detail how to habituate. the horizontal expansion in the symposium gives a detailed examination of such detachment. fi. in the horizontal expansion the habit of detaching is being built up; it needs solidification. the next step, the contemplation of the multitude of deindividualized instances of beauty, is for this purpose. it lasts until the intellectual power of the soul has become strong enough to take the final step. y. this step is the leap to the vision of the beautiful itself. the goal of the methodos is reached. looked upon from the viewpoint of the epistemology in the phaedo, the leap is the soul's transcending the scope of second-hand knowledge of ideas - the scope to which the intellectual achievement of the genuine philosopher in his lifetime is limited - to gain direct contact with the idea of beauty. since the thea is the basis of all forms of dianoia, and since there is in the context in the symposium no bar, explicit or implicit, to applying the same methodos generally to the acquisition of knowledge b - , d - a and c - . a - , a -b , c -d . l. c. h. chen of all ideas mentioned in the phaedo (among which the idea of beauty is found), the philosopher by his leap obtains the desired knowledge in every respect. it turns out that the detachment of the soul from the body in order to acquire first-hand knowledge of ideas need not be so radical as demanded in the phaedo, namely, the complete separation of the soul from the body, or death; the detachment of the soul from senses alone suffices for the purpose, while other life-processes can still go on. throughout the whole methodos from the sense-perception in the beginning to the vision of beauty itself at the end, the philosophos is alive; he need not wait for death to acquire the desired knowledge. here we have plato's answer to the question of how we come to have knowledge of the idea of beauty in contrast to the answer to the same question in general in the phaedo. the answer is optimistic, differing from the pessimistic answer in that dialogue, first in points of view and secondly in the detailed execution of the detachment. university of south florida ludwig c. h. chen cl -d . namely, first in respect of direct vision and then in respect of intellectual running-through (stivola). article contents p. p. p. p. p. p. p. p. p. issue table of contents classical quarterly, vol. , no. , front matter [pp. i - iv] aristophanes and the prometheus bound [pp. - ] the plague of athens: - b. c. epidemic and epizoötic [pp. - ] the progress of epiteichismos [pp. - ] prodikos, 'meteorosophists' and the 'tantalos' paradigm [pp. - ] five late manuscripts of euripides, hippolytus [pp. - ] the koprologoi at athens in the fifth and fourth centuries b. c. [pp. - ] ig ii , philonides and aristophanes' banqueters [pp. - ] Πανcompounds in plato [pp. - ] knowledge of beauty in plato's symposium [pp. - ] isocrates on the peace treaties [pp. - ] crantor and posidonius on atlantis [pp. - ] callimachus, the victoria berenices, and roman poetry [pp. - ] notes on the text of lycophron [pp. - ] pliny hn . and the marriage of tiberius gracchus [pp. - ] lucretian ridicule of anaxagoras [pp. - ] the date of anon. in theaetetum [pp. - ] vergil and the politics of war [pp. - ] the taciturnity of aeneas [pp. - ] atlas and axis [pp. - ] problems in epode [pp. - ] four notes on the herods [pp. - ] did galba visit britain in a. d. ? [pp. - ] martial on patronage and literature [pp. - ] three women in martial [pp. - ] arrian at the caspian gates: a study in methodology [pp. - ] 'me quoque excellentior': boethius, de consolatione . . [pp. - ] the epigrams of sophronius [pp. - ] shorter notes thucydides . . : astyochos' office [pp. - ] euripides, orestes γαλήν̓ > γαλη̑ν, or how a blue sky turned into a pussycat [pp. - ] post-classical Λέσβιαι [pp. - ] catullus' divorce [pp. - ] an acrostic in vergil (aeneid . - )? [p. ] the civil status of corydon [pp. - ] 'omnibus unus' (aeneid . ) [pp. - ] anth. lat. . (riese) [p. ] back matter [pp. v - v] april politecnico di torino repository istituzionale computer analysis of face beauty: a survey / a. laurentini; a. bottino. - in: computer vision and image understanding. - issn - . - stampa. - ( ), pp. - . original computer analysis of face beauty: a survey publisher: published doi: . /j.cviu. . . terms of use: openaccess publisher copyright (article begins on next page) this article is made available under terms and conditions as specified in the corresponding bibliographic description in the repository availability: this version is available at: / since: elsevier computer analysis of face beauty: a survey aldo laurentini and andrea bottino dipartimento di automatica e informatica, politecnico di torino, corso duca degli abruzzi, , , torino (corresponding author. full address: dipartimento di automatica e informatica, politecnico di torino, corso duca degli abruzzi, , , torino italy. tel: + , fax: + e-mail: andrea.bottino@polito.it) abstract. the human face conveys to other human beings, and potentially to computer systems, information such as identity, intentions, emotional and health states, attractiveness, age, gender and ethnicity. in most cases analyzing this information involves the computer science as well as the human and medical sciences. the most studied multidisciplinary problems are analyzing emotions, estimating age and modeling aging effects. an emerging area is the analysis of human attractiveness. the purpose of this paper is to survey recent research on the computer analysis of human beauty. first we present results in human sciences and medicine pointing to a largely shared and data- driven perception of attractiveness, which is a rationale of computer beauty analysis. after discussing practical application areas, we survey current studies on the automatic analysis of facial attractiveness aimed at: i) relating attractiveness to particular facial features; ii) assessing attractiveness automatically; iii) improving the attractiveness of d or d face images. finally we discuss open problems and possible lines of research. index terms— face image analysis, face attractiveness, facial features, machine beauty analysis introduction: face analysis problems the analysis of d or d images of humans is a main research topic in pattern analysis and computer vision. applications exist, or are forecast, in a number of areas such as identity verification, natural man-machine interfaces, surveillance, forensics, sport performance enhancement, medical diagnosis and treatments. special attention has been devoted to the images of hands ([ ], [ ]) and faces, the tools of most human- environment interaction. in particular, the human face is by far the part of the body which conveys most information to human beings, and thus potentially to computer systems ([ ], [ ]). such information includes identity, intentions, health and emotional states, attractiveness, age, gender, ethnicity, attention and personality traits. in several cases the analysis of this information is a multidisciplinary problem, involving areas of computer science (such as pattern analysis and computer vision), human science (such as psychology, behavioral and cognitive sciences), and medicine. at present, the most studied and successful application of face image analysis is identity recognition or confirmation ([ ], [ ], [ ], [ ]). for expressionless faces, the problem is essentially one of d object recognition, at least on short time intervals. unrestricted identification may require the analysis of additional elements such as expressions and aging, involving much more complicated face models and a multidisciplinary approach. other face analysis problems are intrinsically multidisciplinary and strictly related to human sciences and medicine. the most important are estimating age and modeling face aging, capturing and understanding human expressions, and analyzing face attractiveness. face age synthesis and estimation, surveyed in [ ], has possible application in entertainment, forensics, security controls, and cosmetology. computer analysis of human expressions is a much studied problem. a currently well-established application is capturing human expression in order to animate the faces of virtual characters for entertainment or to reduce video-transmission bandwidth. a much more challenging problem is interpreting facial expressions, i.e. mapping expressions onto emotional states ([ ]). one difficulty is that there is no full agreement in psychophysiology about a model of the human emotions and of their effects on facial features ([ ], [ ]). the computer analysis research in this area has been surveyed in ([ ], [ ], [ ], [ ]). today, research is mostly focused on affective computing, i.e. investigating new affect- sensitive paradigms of man-machine interaction. the computer analysis of face attractiveness is an emerging research area. what produces the human perception of beauty is a long standing problem in human sciences and, more recently, in medical areas such as plastic surgery and orthodontics. in the last few decades, several thousand papers and books on this subject have been published. a survey of the recent research on attractiveness in human sciences can be found in [ ]. the researchers involved in these studies are social and developmental psychologists (in relation with the effects of attractiveness on human interaction), cognitive psychologists and neuroscientists (which investigate the mechanisms we use in assessing attractiveness) and evolutionary psychologists and biologists (which study the connection between the morphological characteristics connected with facial attractiveness and other human qualities such as health, fitness and, based on darwin's theories of natural and sexual selection [ ][ ], reproductive value; these works are surveyed in [ ][ ]). the human perception of attractiveness is also related to face identification. experiments have shown that the recognition rate is better for attractive and ugly faces, and lower for attractively average faces [ ]. studying beauty with pattern analysis and computer vision techniques is a relatively new research field. the purpose of this paper, which extends the preliminary material presented in [ ], is to survey the rationale, techniques, results, applications, open problems and new possible lines of research in this emerging area. to the best of our knowledge, these topics have only been surveyed briefly before in [ ]. the content of the paper is as follows. in section , we summarize some results about facial attractiveness presented in human sciences and medical areas. particularly relevant are the results showing that the perception of human beauty appears largely shared by people different in culture, ethnicity and age, and thus supposedly data-driven. these findings are a rationale of computer techniques attempting to emulate the human perception on the basis of objective facial features. in section , we present the applications of automatic beauty analysis. in section , we briefly survey some issues relative to the representation of faces and the extraction of facial features. in section , we survey the recent research on computer beauty analysis, and in particular: i) relating attractiveness and facial features; ii) automatically assessing face beauty; iii) improving attractiveness of d face images or d face scans. finally, in section , we discuss new areas of research and the open problems. beauty in human sciences and medicine . research on attractiveness: a short history what is beauty? philosopher, scientists and artists have debated the problem for centuries. a controversial long lasting question is, according to an often quoted sentence of the writer margaret wolfe hungerford ( ), if “beauty is in the eye of the beholder”, i.e. if beauty is purely subjective or not. important personages, such as immanuel kant ( ), have supported the former thesis or, as david hume ( ), the latter. in any case, from ancient greek culture to our times, no one denied the strong influence of beauty on human life. a number of recent studies, as well as everyday common experience, show that face and body harmony is extremely important in general social life ([ ][ ][ ]). in a society that is virtually obsessed by beauty, looking unpleasant or different can deeply affect self-esteem and result in social isolation, depression and serious psychological disorders ([ ][ ][ ][ ][ ]). attractive people are also likely to be regarded as better than unattractive people in a broad social sense. for instance, experimental research shows that better-looking candidates are more likely to be hired than equally qualified but less attractive people ([ ][ ][ ]). thus, it is not surprising that more money is spent annually in the us on beauty related items or services than on both education and social services [ ]. beauty canons since ancient times, the supporters of the objective and measurable nature of beauty have attempted to state ideal proportions, or beauty canons, for the human body and its parts. the greek sculptor polycleitus was the first to define aesthetics in mathematical terms in his “kanon” treatise. he also pointed out the importance of symmetry in the human shape. in order to define an aesthetically pleasing face, marcus vitruvius, a roman architect, introduced the concept, still largely used in medicine and anthropometry, of facial trisection, or facial thirds, in which a face can be divided by horizontal lines passing through the hairline, the glabella, the subnasale and the menton (fig. , left). fig. : left: facial trisection, as originally described by vitruvius (c. –c. bc). right: leonardo da vinci’s male head in profile with proportions renaissance artists, such as leonardo da vinci, leon battista alberti, albrecht duerer and piero della francesca, reformulated and documented the classic canons. (fig. , right). the classic and neoclassic canons ([ ][ ][ ][ ]) have been used for centuries by sculptors, painters, and are a rough working guide for plastic surgeons. the same idea is at the base of some of today’s beauty assessing techniques, which are merely based on geometric features computed from the position of d/ d facial landmarks. the golden ratio a long lasting idea, also stemming from the classic concept of ideal proportions, is the relevance of the golden ratio to facial beauty. the golden ratio is an irrational number, approximately . , related to geometric entities, such as pentagons, and to mathematical entities, such as the fibonacci sequence [ ][ ]. from ancient times, it has been used explicitly, or claimed later to have been used, by a score of sculptors, painters, architects and composers, ranging from fidia to le corbousier, dalì, mondrian and bela bartok, to construct aesthetically attractive shapes and even sounds [ ]. nowadays, the idea of a universal standard of beauty based on the golden ratio (fig. ) still has several supporters ([ ][ ][ ][ ]). marquardt derived a facial mask summarizing the ideal proportions, an idea that received some support in the plastic surgery community ([ ][ ][ ]). however, several experimental studies found little correlation between the asserted ideal proportions and the beauty scores given by human raters ([ ][ ][ ][ ][ ]). for instance, it was found that patients who were considered to be more attractive after orthognathic surgery were equally likely to move away from or towards the golden proportions [ ] and a wide range of cephalometric values was found in a d research on professional models [ ]. fig. . the proportions of the face and the golden ratio face morphometry morphometric studies have been carried out in anthropology and medicine to find typical measures of facial or body features for different age, sex and ethnicity groups. in the th and th centuries most measurements were relative to bones and skull. recently, due to the pressure of plastic surgery, the focus of these studies has moved toward the analysis of elements relevant to attractiveness, and consequently toward soft tissue morphometry. the attention has also shifted toward the soft tissue proportions in dentofacial orthopedics ([ ][ ]). face soft-tissue morphometry has been investigated in particular by farkas ([ ][ ]), who proposed hundreds of possible facial measures and proportion indices, whose average values have been experimentally determined for several populations and compared with some of the classic canons of beauty ([ ][ ][ ][ ]). several morphometric studies have been aimed at investigating the shape of beautiful faces ([ ][ ][ ][ ]). for instance, in [ ], the comparison of the d scans of geometric features extracted from normal young italian women and a group of beautiful women in the last stages of a beauty competition pointed to some differences between normal and beautiful faces, such as a larger facial upper third and a smaller lower third for beautiful women. a few studies analyzed as well the contribution to attractiveness of facial details, such as young adults' d lip shape ([ ]), eye obliquity ([ ]), eyebrow shape ([ ]) and periorbital zone ([ ]). in this section we present some result relevant to the computer analysis of attractiveness, and in particular to the construction of computer systems able to emulate the human perception of attractiveness. three kind of results support the thesis that the human perception of attractiveness is largely shared and appears to have a biological, “hard-wired” basis. • a large number of empirical tests showing high beauty rating congruence over ethnicity, social class, age and sex; • brain activity patterns due to explicit attractiveness judgments, showing a strong correlation with beauty and ugliness; • the apparently innate capability of young babies to appreciate attractiveness. cross cultural consistency of beauty judgments a large number of experiments, based on various groups both of human raters and subjects, investigated the cross- cultural consistency of the judgments of attractiveness. for instance, pearson correlations greater than . were obtained in [ ] for groups of asian, hispanic, black and white americans, male and female, both as subject and judges. similar close agreements were obtained with greek men as subjects and european and asian females as raters [ ], male/female white and cruzans (native of the virgin islands) as raters and cruzans as subjects [ ], asian-american and caucasian female [ ], south african and american males and females [ ], and black and white judging males and females of both groups [ ]. other experiments used synthetic faces, [ ][ ], once again obtaining cross-cultural congruence of judgments between japanese and caucasian. in addition, high correlation of intra-class ratings between different professional groups was recorded. for instance, in [ ], the correlation of ratings of clinicians specialized in orthodontics and normal hospital clerks was, on average, . for female subjects and . for male subjects, with a significantly higher correlation between ratings of professional evaluators. the temporal consistency of raters was also tested. an overall correlation between ratings given at weeks interval was on average . for female and . for male subjects, and, again, significantly higher for professional groups. the conclusions of these and many other empirical studies is that substantial beauty rating congruence exists over ethnicity, social class, age, and sex. beautiful faces of different groups can have quite different shapes, but they are largely recognized as beautiful by individuals of other groups. furthermore, it has been found that rating congruence is stronger for very unattractive and very beautiful faces ([ ][ ]), in agreement with the analysis of brain activity patterns. these findings, although very largely shared, are in part contested in [ ], where the thesis is that, due to systematic misinterpretation of experiments, individual tastes matter almost as much as shared tastes. brain activity patterns an important result in psychophysiology and neuropsychology is the detection of the brain areas where the assessment of facial beauty is processed. activity patterns related to an explicit attractiveness judgment of d face images have been measured with mri (magnetic resonance imaging) techniques and correlated with the beauty score of the faces. brain patterns showed a non-linear response profile, with a greater response to highly attractive and unattractive faces. in addition, the response is greater for beautiful faces of the opposite sex ([ ][ ][ ]). these experiments have been substantially confirmed using near-infrared spectroscopy (nirs) [ ] and event- related brain potentials (erp) [ ]. these results, although preliminary, are important, since they confirm those of the previous section, and could supply in perspective “objective” measures of the intensity of the perception of attractiveness, without the need of marks and scales whose levels are necessarily ill defined. very young babies prefer beautiful faces another empirical finding seems to indicate that appreciating beauty is an innate, “hard-wired” human capability. newborns were found able to distinguish between faces previously rated as attractive or unattractive by adult raters analyzing the time spent by the babies in looking at each face ([ ][ ][ ]). these preferences are not likely to have been produced by stereotypes of contemporary culture, contrary to those shown among children toward their peers from or years of age [ ]. applications of machine beauty analysis the ability of automatically ranking attractiveness, and suggesting how to improve the attractiveness of a particular face, are at the basis of many applications in scientific, professional and end user areas. some of these applications, as other face analysis applications such as identifying emotional and health states, could raise ethical concerns. human sciences. much research in human sciences requires rating face attractiveness. automatic ratings can avoid using human panels, cumbersome to set up and manage. social life. several internet sites already offer beauty ranking, or beauty ranking programs. choosing the best photographs for home albums, social networks or personal web sites, are possible applications in this area. professional applications. include automatically retouching and deblemishing images for advertising, magazine covers, motion pictures and special effects, preparing professional portfolio or cvs, and screening applicants for specific jobs such as entertainment and modeling where attractiveness is a basic requirement. selecting make-up and hairstyle. we have underlined the large amount of money currently spent for improving female attractiveness. then, applications able to suggest make-up and/or hairstyle not only fashionable, but also fitting a particular face, could be very successful. supporting plastic surgery and orthodontics. a large number of papers on facial attractiveness have been published in plastic surgery and orthodontics journals. several computer tools for treatment planning have been proposed, able to present images of possible outcomes in d [ ][ ] or d [ ][ ][ ], taking into account to some extent surgical constraints ([ ]). how to manipulate the face images, as well as the evaluation of the results, is currently left to the surgeonʹs judgment. beauty analysis programs able to evaluate the different simulations or even to suggest how to enhance the attractiveness of a particular patient, would significantly enhance planning effectiveness. face feature extraction and the face space paradigm in this section we will briefly review some concepts related to face image analysis that are also relevant to the case of attractiveness analysis. holistic and feature based facial data. the computer approaches to facial feature extraction can be roughly divided into holistic and feature based. both approaches are aimed at extracting, for a given problem, the most useful data from the huge amount of information provided by d images or d scans. the difference is that holistic techniques perform an automatic extraction of the data, usually from the whole face, on the basis of some general rule (pca, lda, gabor wavelets, etc.). the precise meaning of the data obtained, a complex combination of the original image data, is not intuitive, and difficult to relate to the usual facial features. in the feature based approach the significant features are selected a priori (e.g., nose width, intraocular distance). the meaning of these features is clear, but elements relevant to the particular problem could have been overlooked. in human science area, the same terms holistic and feature based have been used by perceptual psychologist experimentally investigating the relative relevance to human perception of the whole face and of its parts. ([ ][ ]). anyway, both types of data have been used in computer attractiveness analysis. finding relevant facial features. automatically finding the prominent features of the face, like nose tip, eyes, and the related keypoints or landmarks is a preliminary task in most face attractiveness research. it is required not only by feature based approaches, but also by holistic techniques, for image alignment and scaling. in the d scenario, altough there is room for further improvements, recent research is effective in dealing with changes in lighting conditions, facial expression, pose and orientation and the presence of artifacts like spectacles, hair, beards and moustaches ([ ][ ][ ][ ][ ][ ]). references to more seasoned approaches can be found in the surveys [ ][ ][ ][ ][ ]. while a comprehensive d survey is still lacking, references to the principal techniques can be found in [ ][ ][ ]. the face space. a useful tool for face analysis applications is the “face space” paradigm, used in both human science, for modeling human perception, and in computer analysis. in the computer science area it was first introduced in [ ]. the general idea proposed was that, after proper normalization, the pixel array of a face image can be represented as a point, or a vector, in an image space. the same concept applies to other d or d face data spaces, such as depth maps, d textured points and deformable faces. a vast portion of vectors in these spaces does not represent faces. human faces, constrained by symmetry and general structure, belong to a manifold, called the face space, or face manifold, whose dimensionality is much lower than that of the representation space, but whose shape is highly nonlinear [ ]. investigating the properties of the face space in relation with various face analysis problems requires techniques referred to as manifold learning ([ ][ ][ ][ ]). the relation of manifold learning with computational attractiveness will be discussed in more details in section . human science researchers, and perceptual psychologists in particular, suggest, in the perceptual face space, norm-based models ([ ][ ]), where each face can be described encoding its differences from a prototype face, obtained as the average face. such representations have been used for modeling the perception of identity ([ ]), expressions ([ ]) and attractiveness ([ ][ ]). since computer face models, such as that of blanz and vetter [ ], are currently used to populate the perceptive face space, and various quantitative techniques such as mds (multidimensional scaling) are applied to data analysis, the ideas of face space of computer scientist and psychologists are currently converging ([ ], [ ], [ ]). computer-based beauty analysis the recent papers on attractiveness that make use of image processing, computer vision and pattern analysis techniques surveyed in this section are divided into three main groups: - papers aimed at relating attractiveness to general facial features, such as texture, shape, symmetry, averageness and sexual dimorphism; - papers essentially proposing automatic beauty rating systems aimed at emulating human judgment; - papers describing techniques to beautify d or d face images. . relating attractiveness to general facial features shape and texture shape and texture convey different information and several studies have been aimed at investigating their relative relevance to attractiveness. it should be observed that facial texture also supplies to the human vision system d shape information, since reflected light also depends on the surface normal. in [ ], different skin textures obtained from photographs of women were applied to a common d face model and rendered with the same illumination in order to (partially) decouple texture from original shape. experiments showed that the d models textured with the images of younger subjects were rated as more attractive than those textured with images of older subjects. several other results support the importance of skin color texture for attractiveness [ ][ ], especially in intersex evaluation, a thesis also put forward by darwin [ ]. an interesting, although obviously extreme, example of the importance of texture is reported in fig. , where the same d surface can completely change its d appearance when different textures are applied. in any case, we recall that both the textures retain clues of the original d shapes. a consequence of these findings is that simply relying on geometric dimensions related to landmarks appears insufficient for a full attractiveness analysis. this also questions the effectiveness of canons or golden ratios as efficient beauty predictors ([ ], [ ]). fig. : different textures on the same d shape (courtesy of bronstein et al, int.j of comp.vision, ) symmetry and averageness according to evolutional theories, symmetry may reflect the potential of an individual's genome to resist disease and maintain normal development in front of environmental perturbations, thus being a potential element of sexual mating selection [ ][ ]. a pioneer in these studies was sir francis galton, darwin’s cousin, who in created photographs where the images of different faces were superimposed ([ ]). today researchers use image processing techniques to find the sagittal (symmetry) plane, locating facial landmarks, measuring asymmetry, and creating artificial symmetrical, morphed and average faces. faces are more or less asymmetric around the sagittal plane (see fig. ). usually, their total asymmetry (ta) is decomposed into a fluctuating asymmetry (fa), concerning random deviations, and a directional asymmetry (da), involving a significant bias of the symmetry distribution towards the left or right side ([ ]). da asymmetries can be estimated as the average of squared distances between mirrored left and right corresponding feature points, and fa as the average variation on the average. the effects of measured asymmetry on attractiveness perception have been investigated in several experiments ([ ][ ][ ][ ][ ][ ][ ]), comparing human ratings for original and symmetrized male and female faces. low degrees of asymmetries do not seem to affect attractiveness and some research even found a negative correlation between symmetry and attractiveness [ ]. the effect of averageness on attractiveness perception is a much studied problem, but the results presented are controversial. according to theories of evolutionary biology and cognitive psychology, evolutionary pressure operates against the extremes of the population, and average facial prototypes should be preferred by conspecifics ([ ][ ][ ]). in [ ][ ][ ] composite or average d face images were created by normalizing the eyes and mouth position of frontal images and averaging their pixel values (as in the examples in fig. ). the images were then rated and their ranks compared with those of the original faces. the results are controversial. for female faces, the ratings of composite faces were better than those of the original faces. however, as pointed out in [ ] and [ ], composites are more symmetrical and fairly free of facial blemishes. for male faces, composites were found to be less attractive than normal faces ([ ]). a possible reason is that the most sexually attractive male faces are those that show strong features (e.g. wide jaw), which are perceived as dominance indicators and resistance to parasites ([ ][ ][ ]). in [ ], using the d normalized positions of landmarks, the average face of about samples was computed. then, each test face was warped both toward and in the opposite direction of the average face. human reaters preferred faces closer to the average face, and moving faces far from the average towards the mean point was found to be an effective beautification technique [ ]. however, this result is questioned by [ ] and [ ], according to which average faces are attractive, but very attractive faces are not average. attractive composites were found more attractive by exaggerating the shape differences from the sample means ([ ]). a d analysis of the influence on attractiveness of averageness of both d shape and d texture, using the blanz and vetter morphable model technique [ ], is described in [ ]. the head shapes and the face textures of young adult males and females were separately averaged, and artificial face images were created in two different ways, first by texturing the individual heads with the average texture, and then morphing individual textures onto the average d head. renderings of the original, the texture-normalized and the shape-normalized d models were rated by a human panel, showing higher attractiveness scores than those of original faces for texture-normalized and even higher for shape-normalized images. fig. : effects of symmetry: original face, left and right symmetries fig. : averaging faces improves (female) attractiveness (for each row, the rightmost image is the average of the two images on the left). sexual dimorphism sexual dimorphism is the difference in facial features due to sex. while there is widespread agreement in human science that for female faces femininity is attractive, contradictory results have been presented for male faces (see [ ] for a list of relevant papers). however, some recent papers using computer techniques provide results which appear to clarify this controversial point. in [ ] d faces were morphed from masculinity to femininity according to the eigenvectors, derived from facial landmarks, more significant for sexual dimorphism. the attractiveness of a set of male samples rated by a human panel was found not related to masculinity. on the contrary, significant negative correlation was found for a set of female samples. in addition, the skin color was significantly correlated with male attractiveness, showing the different role of shape and texture as attractiveness clues. a further investigation ([ ]) was performed in a densely populated d face space with dimensions, related to shape and to surface reflectivity. the ratings of four thousands synthetic male and female faces were used to build a non linear attractiveness regressor, which showed predictions in agreement with the human panel. using as the sexual dimorphism direction the vector joining the average male and average female faces, i.e. the direction of masculinity, or, equivalent, as the opposite vector, i.e. the direction of femininity. the gradient of female attractiveness was found to be almost parallel to the direction of femininity, while for male the direction was almost orthogonal. a further analysis, carried on separating shape and reflectivity, showed that for female the gradients due to both features pointed to the direction of femininity, while for male the reflectivity components pointed towards masculinity and the shape components towards femininity. this finding might explain the contradictory effects of masculinity on male attractiveness reported in previous work. . assessing beauty several papers have been aimed at automatically rating face attractiveness. since these systems compute a single attractiveness score, their purpose, even if not explicitly stated, is to approach the average score supplied by human raters, or in other words, the “average” beauty. till now, little investigation on personal preferences is reported ([ ], [ ]). the general approach is: i) collecting a training set of images rated for attractiveness by human panels, ii) extracting from the images, with various techniques, data relevant to attractiveness, and iii) using this data to construct an automatic rater, which is then compared on a test set with human ratings, assumed to be the ground truth. attractiveness estimation in principle can be considered as a classification or a regression problem. human raters are asked to rate face attractiveness with some integer number. each number can be considered as the label of a class, thus making attractiveness estimation a classification problem. classification accuracy can be estimated as the percentage of the test samples assigned to the classes chosen by human raters. since usually, the attractiveness ratings of the human judges are not coincident, the ground truth class is the average or median score. accuracy of estimation can be also evaluated as the pearson correlation between automatic and human ratings over the test set, or as the mahalanobis distance between ground truth and predicted class. on the other hand, the beauty level can be seen as the dependant variable of some kinds of regression, where the feature vector components are the independent variables. accuracy can again be evaluated as the correlation with human ratings or through the coefficient of determination r . the relevance to attractiveness of the different features used can be studied in various ways, such as evaluating the explanatory power of independent variables, or testing the correlation with human judgment of different variable sets. in the following discussion, the approaches presented have been divided into three groups. the first two are the approaches working with a relatively small dataset and based on, respectively, geometric, holistic or mixed features. the last group includes the approaches working with large datasets collected over the internet. most relevant data on several of these papers are summarized in table , namely: • dataset used • score levels, i.e. levels of attractiveness used by human raters • number of raters • facial feature used • classification/regression techniques • validation method (training and test sets) • comparison with human raters some papers also present analyses of the rating consistency. for instance, in [ ], using a ten point scale, a standard deviation of . was found for the average ratings distribution on a particular subject. lower spreads resulted for high and low marks. in [ ], an average correlation of . was found by dividing at random many times the ratings into two groups, and similar results were obtained in [ ]. the consistencies are in good agreement with those found by human science researchers and reported in section . . small data-bases: geometric features several researchers used purely geometric features, based on the automatic or manual identification of facial landmarks. some of such facial beauty scoring systems ([ ][ ][ ][ ]) rely on a set of ratios between landmark distances to first describe a face in the face space and then infer the score of a new image, showing a significant correlation between automatic and human scores. the relation of these ratios to the age, ethnicity, gender and sex of the referees and some classical beauty canons was also analyzed. for instance, in [ ] it was found that female scores are likely to be higher for male faces and that vertical face proportions play a more significant role than horizontal proportions. in [ ], the authors reported that the faces obtaining the top scores did not respect the golden proportions and, in [ ], neither classic geometrical rules nor symmetry were found to be effective beauty predictors. other approaches, such as [ ] and [ ], relied on geometric facial measures only. some feature dimensions, such as lower lip thickness, were found in [ ] to be positively associated with attractiveness, while others, such as nose size, negatively. however, the results obtained were not fully consistent across different contributive analysis algorithms. in [ ], it was also found that, classifying images into categories, the highest attractiveness level reached very high accuracies ( . % correct classification with respect to ground truth scores) and the other levels a lower or much lower one, which relates with the highest labeling confidence of human raters towards highly attractive and unattractive faces. small data-bases: mixed or holistic features other attractiveness rating approaches used data extracted with holistic or mixed techniques. skin textural characteristics and geometric features were used in ([ ]), eigenfaces, geometrical distances, hair colors and skin smoothness in ([ ]), gabor features, eigenfaces and geometric features in ([ ]), data extracted with pls (partial least square analysis) and geometric techniques in ([ ]), eigenfaces obtained with both pca and kpca in ([ ]), and shape and reflectivity data in ([ ]). the results presented in these papers about the relative relevance of geometric, textural and holistic attributes to attractiveness are rather controversial and do not contribute a shared view about this point. geometric based beauty prediction performed better than holistic in [ ] and texture based in [ ], while textural features outperformed geometric ones in [ ]. the integration of features of different natures, textural and geometric, provided better accuracies than the individual features ([ ] [ ]). some attempts to analyze the relative relevance of data extracted with holistic techniques were performed. in [ ], it is reported that the eigenfaces showing higher significance for the human attractiveness ratings do not correspond to the highest eigenvalues, providing a general description of hair and face contours, but to the intermediate and smaller ones, which contain clearer details of facial features like nose, eyes and lips. on the contrary, the pls factors found more relevant in [ ] appeared related to averageness, symmetry and sexual dimorphism. internet collected images several researchers have attempted to use larger training databases, collecting images from the internet. in this case, a major challenge to face is related to the large variability and low quality (i.e., different resolutions, orientations, illuminations and expressions) of the images used. another relevant issue is obtaining human ratings for such a large numbers of images. to solve this problem, researchers often relied on images taken from hotornot.com, a site that allows users to rate, on a point scale, the attractiveness of photos submitted voluntarily by others. in particular, a selection and rectification of the best images between . rated samples downloaded from this site, was performed and described in [ ] this set, contains female and male images and, among the others, was also used in [ ] for constructing an average face model that evolves as a function of attractiveness score and allows to analyze the differences of the facial traits at different beauty levels. as for small databases, different approaches to assessing attractiveness have been proposed, often resulting in contrasting findings. in [ ], geometric ratios and eigenfaces were experimented in different classifiers, showing a better accuracy for eigenfaces. different data, including eigenfaces, edge information and data extracted by various layers of local filter banks were used in [ ] to train various regression models. top correlation with the attractiveness scores was obtained using multilevel filter banks, outperforming by far eigenface results. another study on female face portraits ([ ]), analyzed different facial features (i.e. geometric features, color characteristics, and non-permanent traits as make-up and expression) and photographic aesthetics (i.e., image format and resolution, illumination and so on). face shape and clues of the person’s weight and baby-faceness were found more relevant that non-permanent traits, while image quality was marginal. in [ ], rather than attempting to develop a “universal” attractiveness predictor, the authors tried to build an automated scoring system for learning the personal preferences of individual users from their ratings of a set of example images. eigenfaces, gabor filters, edge orientation histograms, and geometric features were used to train a svm regressor. however, results were not particularly promising, with a top average pearson correlation with human scores ( . ) obtained with gabor filters. a similar approach ([ ]), based on a combination of geometric and textural features, attempts to learn the personal relative ranking of facial attractiveness, i.e. sorting a set of faces in order of perceived attractiveness rather than assigning a beauty level to an incoming image. results are in good agreement with users’ personal taste. small - geometric technique database score levels panel size facial features used classification technique / beauty predictor validation method accuracy size gender expr. color arabi [ ] f n n ratios of inter- landmarks distances modified knn (using a weighted euclidean distance) training , testing % of correct classification for images where features have been accurately identified, much lower when localization errors are present gunes [ ] f n n ratios of inter- landmarks distances decision trees, multi- layer perceptron, kernel density estimation fold cross validation accuracy defined in terms of the mahalanobis distance between ground truth and classification results. values in range [ . , . ] according to the classifier (but always less than a class) gunes [ ] f n n ratios of inter- landmarks distances c . a) training , testing b) fold cross validation accuracy defined as in gunes [ ]. a) average mahalanobis distance = . b) average mahalanobis distance = . schmid [ ] f/m n n variables (ratios of feature dimensions, symmetry data, closeness to neoclassic canons) regression analysis n/a r = . for the complete model with variables r = . for an optimized model containing only predictor variables fan [ ] f n y geometric ratios, reduced with pca to feature variables non linear regression for training, for testing r = . joy [ ] f n y n/a n/a inter-landmarks distances artificial neural networs -fold cross validation % of correct classification mao [ ] f n n n/a geometric features svm and c . a) class classification b) class classification (class separation given by the median of all scores) % ( ) for training, % ( ) for testing a) on average, . % (higher on highest attractiveness level, lower or much lower on other ones) b) . % small – mixed/holistic technique database score levels panel size facial features used classification technique / beauty predictor validation method accuracy size gender expr. color kagian [ ] f n y geometric features reduced to by pca, + non geometric data (related to asymmetry, smoothness, color of selected areas) linear regression leave-one-out cross validation . pearson correlation eisenthal [ ] set : (low qualit y) set : (high qualit y) f n n for set , for set two feature sets: ) geometric feature + indicators for symmetry, smoothness, hair color; feature variables were decorrelated with pca ) selected eigenfaces two experiments: a) classification in two classes (attractive- unattractive, as upper and lower % of samples) with knn and svm b) beauty predictor on classes with knn, linear regression (lr), leave-n-out cross validation, n= for knn and lr, n= for svm a) from % to % of correct classification according to dataset, features and classification technique used b) correlation of . using representation and . using representation . an hybrid predictor scores . as correlation svm chen [ ] f n n gabor features, reduced by pca, + kagian features support vector regression and knn, linear regression + feature selection leave-one-out cross validation . pearson correlation ( . using gabor features only) turkmen [ ] f n n eigenfaces (computed with pca and kpca) svm training , testing . % correct classification with pca, . % with kpca bronstad [ ] f/m n n partial least square, geometric feature reduced by pca perceptron leave-one-out cross validation pearson correlations pls: . for female faces, . for male faces geometric features + pca: . for male faces and . for female faces said [ ] (synth etic) f/m n y shape and reflectivity features, both computed with pca non linear regression training, testing r = . for female faces and r = . for male faces internet db technique database score levels panel size facial features used classification technique / beauty predictor validation method accuracy size gender expr. color sutic [ ] set : set : f/m y y > set : geometric ratios set : an unspecified number of eigenfaces classification with knn, neural networks, adaboost in two experiments: a) class classification (class separation given by the median of all scores) b) class classification (boundaries are quartiles of all values) set : for training, for validation and as test set. set : for training, for testing a) % correct classification in the best case (knn with eigenfaces) b) % of correct classification with knn (the feature set was not specified) gray [ ] f y y n/a eigenfaces, multiscale single layer local filters, single and two-layer local filters regression model note: score levels are continuous, recomputed from pairwise ratings for training, for testing top correlation with recomputed ratings: . for multiscale model dantcheva [ ] f y y > landmark locations, geometric ratios, geometric features, expressions, non- permanent traits image attributes multiple regression for training, for testing . pearson correlation whitehill [ ] f/m y n gabor features, eigenfaces, geometric features, edge orientation histograms (eoh) ε-svm regression fold cross validation on the dataset chosen by each rater . correlation with personal preferences using gabor features, . with pca, . using eoh, while geometric features scored only a . correlation altwaijry [ ] f n y n/a geometric features, hog, gist, l*a*b color histograms, eigenfaces, sift, dense-sift reduced with pca rank learning based on a modified svm approach training, testing % accuracy, obtained combining all features except eigenfaces. table : a summary of the assessing beauty approaches described in section . . for each technique, the table shows some information about the db used (number of images, gender of the depicted individuals, female (f) or male (m), presence of expressions, (y)es or (n)o, color images available, (y)es or (n)o), number of score levels used by raters, number of raters of the human panel, and short description of the features used, the classification or regression algorithm, its validation method and results achieved. discussion in general, the computer scores presented appear to relate fairly well to human average scores, and interesting results have been obtained, mainly with regression techniques, on the relevance to attractiveness of particular facial features. however, some comment on the limits of these studies should be made. - experiments are not comparable. most papers, excluding some research based on the same internet images, use test sets not only shot in different conditions, but containing different individuals rated on different level scales by different panels. even if the last point could be not very relevant, given the asserted consistency of human ratings, accuracies are not comparable, even if the same measure of accuracy is used. it follows that it is also very difficult to evaluate the relative merits of the various classification or regression techniques and of the features used. also observe that the same face analysis program with the same accuracy measure could supply very different results by only changing the individuals of the test set. consider pearson correlation for instance. since consistency of human judgment has been found to be low for average faces, and high for very beautiful or very ugly faces, a test set with many average faces would produce for these faces “noisy” judgments, and thus lower correlation than a test set containing mostly extreme cases. similar arguments apply to other figures of merit. it should also be noted that, due to this and other reasons, not only the accuracy measures, but also the usual statistical significance tests presented by some authors have a rather limited meaning. finally, it could be interesting to observe that problems due to heterogeneous databases also affected the first research on expression analysis, as stressed in [ ]. - panel scores are intrinsically “noisy”. a limit to computing the “average” beauty score is the “noisiness” of human judgments. this is due to not only to human preferences, but also the ill-defined meaning of the various levels of the scales of beauty. this also shows that the computer analysis of individual preferences is not easy, since their effects are difficult to tell from those due to ill-defined beauty levels. - test sets lack beautiful faces. the lack of faces rated at top beauty levels is a problem that affects most of the training and test sets used. in [ ] seven attractiveness levels were used, but the top score was only . and in [ ] only . for male and . for women, again on seven levels. in [ ] and [ ], to populate top beauty levels several movie actors were added to the database. also observe that, where explicitly reported, as in [ ] and [ ], top accuracy is obtained for top beauty levels. average attractiveness judgments are much more uncertain both for automatic and human ratings, in agreement with brain activity patterns. - most papers investigate female faces. most of the databases used contain only female images. as a matter of fact, according to various results presented in human sciences, such as those stating that qualities like averageness and symmetry are more closely related to female than male beauty, computer analysis of female beauty is likely to be easier than that of male beauty. - training sets are too small. as already mentioned, results from human sciences point to a large number of beauty prototypes, especially for male faces. this is in agreement with the results presented in [ ], where the accuracy of classification is reported to increase without saturation with the cardinality of the training set. it seems that most training sets were too small, in particular for top beauty levels. internet collected images, although potentially countless, are shot in uncontrolled orientation and lighting, thus image normalization, a necessary preliminary for most feature extraction techniques, introduces more “noisiness” into the process. concluding, given the above reasons and the fact that the material used were only d images, the research aimed at computing an average beauty score appears rather preliminary. . enhancing attractiveness of face images as discussed in section , enhancing attractiveness is one of the most important application area of beauty analysis. here we survey the papers aimed at improving the attractiveness of d images and d scans. summary data on some of these papers are presented in table . d images one idea for automatically enhancing the attractiveness of d facial images, in agreement with the relevance of texture to attractiveness, is to correct face pixel colors. for instance, in [ ] the authors describe a system aimed at beautifying face images by removing wrinkles and spots, while preserving natural skin roughness, using a bank of non-linear filters. another approach to d beautification uses geometric data to warp the image texture toward more attractive shapes. this approach is effective for beautifying faces by making relatively small changes, without affecting the identity perception, and it is aimed at professional retouching for preparing posters, magazine covers and fashion photography services. a system based on this idea, working on frontal color photographs, has been presented in [ ]. the application performs a face triangulation starting from landmark points, obtaining a representative vector of normalized lengths. the vector of the face to beautify is compared using various techniques with the vectors of the beautiful faces. these comparisons suggest how to warp the triangulation of the original face toward those of beautiful faces that are more similar to the original (see fig. ). the resulting face beauty scores show better results for beautification of female faces (the raters found all the modified female samples, but only percent of the male samples, more attractive), probably due to their larger training set. other d face images beautification systems using similar techniques are described in [ ] and [ ]. similar ideas for reshaping the face and filtering its texture are at the basis of the commercial portraitprofessional software. fig. . from left: feature points; face triangulation; original and beautified face ([ ]). observe that identity perception is not affected d scans three systems for automatic beautification of face d scans have been proposed, based on three different approaches. the system described in [ ] attempts to enhance attractiveness by restoring local or global facial symmetry. significant preference of human observers toward the symmetrized faces is reported. another system for the global enhancement of d scans is aimed not only at correcting asymmetry, but also to approach the proportions suggested by neoclassic canons, golden ratio and aesthetic criteria for the face profile ([ ]). human raters preferred the enhanced d faces in . % of the cases. a result reported is that asymmetry correction is more effective than approaching frontal or profile ideal proportions, although it is their combination that produces the best results. the previous systems perform a global d face warping and have possible applications in areas such as computer graphics and animation, avatar modeling, interactive d e-commerce, tele-conferencing and entertainment. however, other important application areas such as plastic surgery or orthodontics deal with real faces, and can only correct locally face features. a system for planning plastic surgery that automatically chooses the shape of the feature to be modified that aesthetically fits the patient’s face best, is described in [ ]. the basic idea of the paper is that, in general, there is not a unique prototype of a beautiful facial feature (e.g. mouth, nose, chin), but there are different shapes that are perceived as attractive, depending on their integration with the rest of the face [ ]. the system searches, in a database of beautiful faces and with anisotropic icp, for the most similar scan, excluding the feature to modify. then, it suitably applies the corresponding feature of the selected beautiful face to the patient’s scan. plastic surgery treatments, relative to chin, nose and mouth, have been simulated. their evaluation by a human panel shows not only an obvious attractiveness improvement, but also that the more similar to the patient the database scan selected, the better its feature fits aesthetically. an example of simulated rhinoplasty is shown in fig. . fig. . simulated rhinoplasty: original scan (upper row) and simulated surgery outcome (lower row) d approaches technique approach reference db face representation panel size results arakawa [ ] non linear digital filter banks, whose parameters are computed using genetic algorithms n/a n/a n/a n/a leyvand [ ] face warping towards the beauty-weighted average of the k closer samples in face space female and male lengths obtained from facial landmarks all female and % of male in the reference db showed an attractiveness improvement (average improvement = %) melacci [ ] face warping towards the distance-weighted average of the k closer samples in face space male and female position of landmarks test set: male and female. attractiveness improvements on % of the test samples sun [ ] face warping towards the most similar prototype; warping is controlled by a learned beauty decision function male and female, from which male and female beauty prototypes were extracted position of landmarks test set: male and female. attractiveness improvements for % of female samples and % of male samples guo [ ] cosmetic transfer from one subject to another. n/a n/a n/a n/a d approaches technique approach reference db face representation panel size results kim [ ] local and global symmetry enhancement of d scans n/a polygonal mesh and facial landmarks all the global and local refinements were preferred, at different levels, by raters liao [ ] local and global symmetrization and modification of facial proportions to approach neoclassical canons, golden ratio and profile aesthetic criteria n/a polygonal mesh, with manually annotated landmarks test set: male and female scans. % of the raters found the enhanced version more attractive bottino [ ] local warping of selected facial regions to conform to that of the k closer beautiful samples female polygonal mesh, with manually annotated landmarks test set: samples. attractiveness improvement in % of the cases scherbaum [ ] automatic suggestion of the best makeup for a given face by transfering the makeup of the reference sample most similar to the incoming d scan female appearance image (a combination of geometric, textural and surface material information) the closer match in the reference db is indeed the one preferred by raters. tests showed that the appreciation of the automatic makeups are similar to that of the professional makeups. table : a summary of the enhancing beauty approaches described in section . . for each technique, the table presents a description of the approach, of the database of reference beauty samples used and of the features used to characterize a face, the number of raters of the human panel evaluating the attractiveness improvements and a short description of the results achieved. selecting make-up and hair style the first approaches presented in this potentially very popular application area were aimed at merging an image of the subject with another image presenting a particular make-up/hairstyle. in [ ] a system for automatically fitting a given hairstyle to a face is described. another paper ([ ]) deals with the automatic transfer of cosmetic styles from one face to another. however both the initial choice and the evaluation of the result are left to the user. scherbaum et al. [ ] recently proposed a system that automates the task of choosing the make-up best fitting a given face using a learning-by-example approach (fig. ). the system relies on a reference database of d scans of female faces without make-up and with a professional make-up. for each of these samples, its appearance (defined as the collection of geometric, textural and surface material information) and its make-up (the change of appearance after makeup) are computed. these data are then used to perform several operations, like determining the best fitting make-up for a new subject, make-up transfer, automatic rating of make-up and even the generation of the face shape best fitting a given make-up (which could be used for didactic purposes). perceptual studies shows that the computer-suggested make-ups are appreciated by a panel of human raters as much as the professional make-ups. fig. : computer-suggested makeup ([ ]). given the d scan of a subject without makeup, the system can either suggest a makeup (suggested makeup), or apply a user-picked makeup (not-suggested makeup). discussion: results obtained and open areas of research the papers surveyed in the previous section show that, although interesting results have been obtained, fully understanding how attractiveness perception relates to various facial elements requires further work. currently, several different elements of beauty have been investigated, but not yet combined in an overall framework. in particular, we do not have a clear picture of what characterizes very beautiful faces, which is of paramount importance for beautification applications such as supporting plastic surgery. in the following subsections, we discuss some open problems and potential areas of research. local analysis of facial details could improve attractiveness analysis several of the reviewed papers analyzing or rating beauty are based on identifying facial landmarks and constructing some representative geometric feature vector. this technique appears convenient for capturing the general harmony of the face, a prerequisite of attractiveness, but facial texture and small details, important elements of beauty, are essentially lost. holistic techniques appear better suited to capture the texture. however, neither usual facial landmarks nor holistic techniques are able to efficiently capture small shape details of particularly important areas, such as mouth and eyes. detailed local analysis of particularly significant areas are considered important for other face analysis problems, such as face and intention recognition (see for instance [ ]), and could substantially improve attractiveness analysis. d research is required the papers surveyed are mostly based on d frontal images of individuals, sometimes monochromatic and of medium quality. most of the d research performed used synthetic faces. in d images much valuable information relevant to attractiveness is lost, for instance the exact d shape of the nose and the chin. moreover, important applications, such as supporting plastic surgery, are essentially d and must deal with d face scans. we believe that significant advances in facial beauty analysis require research performed on d scanned faces, as in other face analysis areas. for instance, using very high resolution d images or d medium quality scans, the frvt face recognition contest showed an increase of one order of magnitude in recognition efficiency compared to frvt [ ]. a review of the currently available d face databases, along with available information regarding scanning device, resolution, precision and annotations, is reported in [ ]. beautiful face databases should be constructed most automatic beauty rating systems, as well as those attempting to beautify faces, rely, for training or comparisons, on samples of faces rated at different levels of attractiveness. therefore, a problem for effective d or d beauty research and beautification techniques is the lack of databases also containing such samples. in particular, few generic d face databases exist, containing relatively small numbers of elements. for instance, the d medium quality feret database contained scans of different subjects, while the d low resolution database contains images of , subjects. a further problem is that most of the subjects are of average attractiveness. hence, in order to carry out further studies on attractiveness, d and d databases populated by faces rated at all levels of beauty should be constructed. assessing beauty: setting up a standard test protocol as discussed in section . , it is impossible to compare the different approaches for automatically assessing beauty. similar problems affected other face analysis applications. in the field of identity recognition, to compare identification accuracy it was necessary to set up the feret contest, where a number of software producers volunteered to comply with a standard test frame. we believe that a necessary step forward in computational attractiveness is to set up a standard test protocol, based on a common database of samples rated on a common scale, including high quality d images and d scans. anyway, this would not solve completely the problem, given the ill defined meaning of the scale levels. beauty analysis as a manifold learning problem most beauty analysis research and applications require an adequate sampling of faces rated for attractiveness, or samples of beautiful faces only. if the sampling is not sufficiently dense, these applications could fail, since the face to rate or to beautify might fall in zones that are under-sampled or not sampled at all. this raises another problem: how many samples are required for an adequate sampling of the face space from the point of view of attractiveness? we already noted that results of the d research hint at an under-sampling of the face space, in particular for very beautiful faces. we can forecast that sampling the d face space for beauty analysis could require a rather large number of samples. this appears in agreement with the idea of many beauty prototypes, which possibly form unconnected manifolds and span many populations of different age, sex, and ethnicity. results such as those of perret et al. [ ] also point to the need of many samples in order to cover unusual but attractive faces. the problem of the adequate sampling is part of the more general problem of learning the beauty related face manifolds. manifold learning techniques have also been found useful for other face analysis, from identity recognition to human age estimation by regression in a low-dimensional subspace [ ]. it should be observed that different face analysis problems refer to different manifolds in the face space. for instance, face identification deals with the manifolds relative to particular individuals. determining ethnicity from faces deals with a few multi- individual manifolds that are likely to have low intrinsic dimensionality. analyzing the face elements relevant to attractiveness could be reformulated as the problem of learning these manifolds, i.e. understanding their intrinsic dimensionality (id, [ ]), and finding data reduction techniques able to transform the face space into a lower dimensionality subspace that preserves attractiveness distances. as for the id of the face space, the results known are mostly related to the problem of identity recognition. ([ ][ ]). for the gender classification problem it has been estimated that the id of the subspaces involved is roughly around / ([ ]). investigating attractiveness with manifold learning techniques is currently an almost open area of research. the only research reported concerns the id of the manifolds of beautiful and unpleasant face profiles. the id estimated was around ([ ]) and the discrimination of the two manifolds was effectively performed with data that was reduced to the id with various techniques. considering expressions in attractiveness research up to now, most attractiveness research has been carried out on expressionless face images. however, the face is highly deformable and, in other well-established areas of human face image processing, e.g. face identification, the expressions, or the d and d changes in face geometry, have been considered very relevant. recent research in human science have found that expressions are relevant to attractiveness perception too ([ ][ ]), although the results presented in these papers for male and female expressions are not consistent. also the analysis of the brain activity patterns has shown that attractiveness is affected by expressions ([ ]). then, extending computer attractiveness analysis to facial expressions appears a new promising area of research. studying dynamic beauty human attractiveness is also related to movements, since static and moving stimuli convey different types of information that can lead to different attractiveness ratings. recent studies in human science dealt with the relation with attractiveness perception of body ([ ]) and face motion ([ ]). to the authors’ knowledge, no sound attempts have been made yet to perform an automatic analysis of the attractiveness of facial movements. acknowledgments the authors would like to thank the anonymous reviewers for their valuable comments and suggestions to improve the quality of the paper. references [ ] aarabi p., hughes d., mohajer k., emami m., “the automatic measurement of facial beauty,” ieee proc. int. conf. on systems, man and cyb., pp. - , [ ] aaron i., etcoff n., ariely d., chabris c., o’connor e., and breiter h.c.,”beautyful faces have variable reward values: fmri and behavioural evidence,” neuron, vol. , pp. - , [ ] abate a., nappi m., riccio d., sabatino g., d and d face recognition: a survey, pattern recognition letters, volume , issue , , pages - [ ] adamson p. and doud galli s., ”modern concepts of beauty,” current opinion in otolaryngology& head and neck surgery,vol. , pp. - , [ ] alley t.r. and cunningham m.r., ”averaged faces are attractive, but very attractive faces are not average,” psychological science,vol. , pp - , [ ] altwaijry, h.; belongie, s., "relative ranking of facial attractiveness," applications of computer vision (wacv), ieee workshop on , vol., no., pp. , [ ] arakawa k. and nomoto k., “a system for beautifying face images using interactive evolutionary computing,” ieee proc.int. symp.on intell. sig. proc.and comm. syst., pp. - , dec. - , hong kong, [ ] asthana, a.; zafeiriou, s.; shiyang cheng; pantic, m., "robust discriminative response map fitting with constrained local models," computer vision and pattern recognition (cvpr), ieee conference on , vol., no., pp. , , - june [ ] atiyeh b.s. and hayek s.n.,” numeric expressions of aesthetics and beauty,”aesth, plast.surg. vol. , pp. - , [ ] baker b.w. and woods m.g., “the role of the divine proportions in the esthetic improvement of patients undergoing combined orthodontic/orthognathic surgical treatment,” int. j. adult. orthod. orthognath. surg., vol. , pp. - , [ ] barash d.p., sociobiology and behaviour, new york, elsevier north holland, [ ] bashour m., “an objective system for measuring facial attractiveness,” plast. reconstr. surg., vol. , pp. - , [ ] bashour m., “history and current concepts in the analysis of facial attractiveness, ”plastic and reconstructive surgery,vol. ,no. , pp. - , [ ] benson p. and perret d., “computer averaging and manipulation of faces,” in p.wombell(ed.) photovideo: photography in the age of the computer, pp. - , london, rivers oram press [ ] blanz v. and vetter t., “ a morphable model for the syntesis of d faces, “ siggraph proc, pp. - , [ ] bottino a., laurentini a., “the analysis of facial beauty: an emerging area of research in pattern analysis”, lecture notes in computer science, vol. / , pp. - [ ] bottino a., laurentini a., ”the intrinsic dimensionality of attractiveness: a study in face profiles”, lecture notes in computer science, vol , , pp - [ ] bottino, a.; de simone, m.; laurentini, a.; sforza, c.; , "a new -d tool for planning plastic surgery," biomedical engineering, ieee transactions on , vol. , no. , pp. - , dec. 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[ ] zhang d., zhao q., and chen f.,” quantitative analysis of human facial beauty using geometric features,” pattern recognition. vol. , pp. - , [ ] zuk m., “the role of parasites in sexual selection: current evidence and future directions,” advances in the study of behavior, vol. , pp. - , [ ] d face and body databases, available online at http://www.polito.it/cgvg/ ddb.html a. laurentini was born in genova, italy, and received the degree of ingegneria elettronica from the politecnico di milano in . in he joined the politecnico di torino, where he has been professor of computer science at the dipartimento di automatica e informatica until november . he is member of ieee and acm, and author of more than eighty scientific papers. his current research interests include computer vision, computer graphics and computational geometry. a. bottino was born in torino, italy, in . he received his master degree in computer science engineering and his ph.d. from politecnico di torino in and . he is currently a researcher in computer science at the dipartimento di automatica e informatica of the same university. he is author of several journal and conference papers. his current research interests include computer graphics, computer vision and virtual heritage. vol : june • juin canadian family physician • le médecin de famille canadien commentary a terrible beauty a physician’s story of ovarian cancer linda j. spano bscn md mhsc ccfp w hen the fourth member of my -person book club was diagnosed with breast cancer, i felt grateful for my own good health and good fortune. we were all baby boomers in our s, western, white, educated, socioeconomically advan- taged women. one in canadian women will confront breast cancer in her lifetime. we had entered the “at risk” population, but these seemed terrible odds. then it was me. i was diagnosed with one of the relatives of ovar- ian cancer—a highly aggressive peritoneal tumour with ascites and widespread abdominal metastases. stage . a woman can get this kind of cancer even if she has had a hysterectomy and oophorectomy. it has become important for me to find a way to make my experience useful to my successors in this ill- ness. few family doctors see many patients with ovar- ian cancer in their practices. in my practice as a family doctor, only women with my diagnosis came to me, both very late in the course of their disease. risk factors and genetic testing i was unaware until i was researching my own blood- line that of the women in my paternal grandmoth- er’s family had died of either breast or ovarian cancer. i had only other risk factor, never having had children. few studies of risk factors have focused specifi- cally on ovarian cancer, but we have learned from the overlap of many studies that have targeted breast cancer; age, familial predisposition, and less child- bearing are shared risks with breast cancer. other risk factors for ovarian cancer include polycys- tic ovarian syndrome and more frequent menstrual cycling, including early onset of menses and late menopause. use of oral contraceptives substantially reduces the risk. having first-degree relative or or more clus- tered second-degree relatives with breast or ovar- ian cancer, especially before menopause, increase a woman’s risk for breast and ovarian cancer. descendants of ashkenazic jews are at greater risk of having the brca and brca genes, which are asso- ciated with a lifetime occurrence of breast or ovarian cancer of up to %. approximately % of the general population carry brca or brca gene. in general, known familial factors account for only about % of ovarian cancers. screening and prevention genetic testing is not something we do for ourselves. we do it to determine choices for our offspring and our sisters and their daughters. testing is for them. regular examinations and papanicolaou smears do not help detect ovarian cancer in its early stages. serendipitous testing, usually to investigate another problem, sometimes uncovers an unexpected early cancer. for those with risk factors, primarily family history or having the brca or brca genes, stud- ies are under way to determine whether biomarkers, such as the cancer antigen test (ca ) and pelvic ultrasound, can alert physicians to the need for further investigations in time. for women at high risk, most physicians recommend annual assessment of ca levels, bimanual pelvic examination, and transvaginal ultrasound for screening, until better measures are developed. the need for better screening methods is clear. the critical question is, will such screening affect out- comes? even when family history is compelling, the drastic step of surgical removal of breasts, ovaries, and uterus is a very difficult step to take based only on probability. the us preventive services task force rec- ommends considering prophylaxis with drugs shown to reduce breast cancer incidence, such as tamoxifen and raloxifene. symptoms my own symptoms hit quickly. there was new pain—pain when my bladder filled, especially at night. there was dis- comfort with intercourse and with pressure on my left lower abdomen. ovarian cancer usually metastasizes into the abdo- men before it causes symptoms. while most public education urges early attention to warning symptoms, only about % of ovarian cancers are diagnosed at a curable stage. by the time symptoms begin—uri- nary urgency, abdominal bloating, bowel irritability, fatigue, painful intercourse—the cancer is virtually always widespread. weight loss, breathlessness, ane- mia, early satiety, and abdominal pain are symptoms that come later. diagnosis most of the women i have come to know experienced the frustration of not having their symptoms recognized canadian family physician • le médecin de famille canadien vol : june • juin commentary as serious. as a result, several weeks or months passed before appropriate investigations were undertaken. one study indicates that most women have symp- toms for at least months before diagnosis. doctors often initiate investigation with gastrointestinal or bowel studies in light of the symptoms, but these studies are generally not helpful. despite its vague presentation, it is the persistence or escalation of symptoms in ovarian cancer that is serious. investigation of suspicious symptoms should include a pelvic examination, assessment of ca levels, and transvaginal ultrasound. on pelvic examination, an adnexal mass is usually evident, but the ovary is not always enlarged. computed tomography scanning is often necessary. pelvic fluid should not be dismissed as “normal,” particularly in postmenopausal women. the ca test is the best single tool we have to identify and follow a tumour. levels, however, are not numerically correlated to extent of disease, except within a given individual. although more than % of women with ovarian tumours have elevated ca lev- els when diagnosed, levels are often not elevated until the cancer has spread. false-positive and false-negative results (early in the disease) can occur. treatment it is not uncommon to think that, faced with this illness, a person might decide not to accept treatment; however, this rarely happens. meeting women who have been through surgery and chemotherapy, who are finding meaningful life not only during the glorious remission, but also during the treatment process itself, will kindle the weakest hope and strengthen the remotest resolve. most of the interven- tions do not add to the quantity of time we live, but rather to the quality. during the past to years, most women with ovarian cancer have had initial surgery to reduce tumour bulk, ideally to microscopic size. almost % of women are candidates for surgery either before or after ini- tial chemotherapy. they might require an ostomy from bowel or bladder structures to achieve the best possible results. surgery is followed by chemotherapy, which usually entails to cycles of platinum and taxane drugs, each lasting to weeks. women with “platinum- sensitive” tumours generally go into a remission lasting at least months. , recently, intraperitoneal chemotherapy as a treat- ment option has been reexamined. a major us study found that a combination of intravenous and intraperi- toneal chemotherapy after primary surgery increased time to recurrence by a median of months and sur- vival by months. although this study demonstrates the first major improvement in survival in many years, it is associated with more severe side effects in the short- term and can be performed only with optimal surgical results and in patients free of other illness. many women i know have sought the advice of thera- pists in the “wellness” or naturopathic movement to try to maximize nutritional and immunologic strengths. other commonly accessed resources include ther- apeutic touch, relaxation, massage, neurolinguistics, healing workshops, and spiritual guidance. there is lit- tle study data available to evaluate these therapies with regard to objective benefits in cancer care, but they are regarded as very helpful by women struggling to cope with the disease. prognosis living under the spectre of a short life expectancy is shocking, confusing, depressing, unnerving, and—some- times—has a terrible beauty. every moment becomes precious. i have had my remission. now i have my own “appointment in samarra.” more than % of those diagnosed with epithelial ovarian cancer are already in advanced metastatic stages. fewer than % of these women will live years. they will be “long-term survivors” and will typically have had several rounds of chemotherapy with shorter and shorter remissions. more than half of those who respond to platinum chemotherapy relapse by to months. median survival ranges from to months. while there are other less lethal types of ovarian cancer, they constitute less than % of cases. relapsed ovarian cancer is currently incurable. while ovarian cancer in canada affects only one tenth of the number of women affected by breast cancer, it will claim more life years. the profile of survival has barely changed in more than years. reactions to diagnosis at some point in our cancer stories, most of us ask “why me?” i am saddened to hear a great deal of misinformation when i listen to answers to that question. resources information about clinical trials • us national institutes of health: www.clinicaltrials.gov • national cancer institute: www.cancer.gov • national ovarian cancer association (canadian): http://ovariancanada.org or www.ovairecanada.org (en français) information for patients and families • ovarian cancer canada: www.ovariancancercanada.ca • national ovarian cancer association (canadian): http://ovariancanada.org or www.ovairecanada.org (en français) • canadian cancer society: www.cancer.ca vol : june • juin canadian family physician • le médecin de famille canadien commentary having cancer is often the subject of shame, blame, or remorse. in addition to their grief, anger, and angst, women often feel a sense of failure. there is very little evidence that women who develop ovarian cancer are different from other women except for their genetic pre- dispositions and reproductive histories. there is no evidence that “bad feelings” cause can- cer or that “good feelings” cure cancer. feelings are just feelings. professionals need to help patients to iden- tify and express their feelings before rushing to explain, suppress, or deny them. hope should never be discour- aged. people do unexpectedly defy the odds. support the stress of living with cancer is enormous. the expecta- tion that we can all emerge hopeful, positive, and coura- geous is an additional burden. added to this, many of the afflicted women i know have no partners and no children. when asked what is most helpful in coping with the distress of this disease, almost all women with ovarian cancer name family, professional caregivers, and other women who have walked the same path before them. understandable information is another key element in coping with cancer. the wealth of information on ovar- ian cancer available on the internet can be overwhelm- ing at times. clinical trials many of us, knowing that our lives will be limited, would be willing to risk the potential consequences of being involved in clinical studies. we offer a good testing model because outcomes become evident within a fairly short interval, and our lives are already compromised. we are long overdue for a national cancer strategy* to help inform the public and coordinate services so that patients know what resources are available and can par- ticipate in studies that are trying to answer key questions. vaccines, monoclonal antibodies, angiostatins (inhib- itors of neovascularization) and stem-cell transplants are among the promising treatments of the future. , , most cancers, including ovarian cancer, occur partly because growth factors are “turned on” without normal control mechanisms. much current research is focusing on ways to block this overactive process. studies are looking at drugs that target human epi- thelial receptor factors because approximately % of women with ovarian cancer have positive test results for this factor. , , other epithelial growth factor receptors are also common in women with ovarian cancer. some tumours trigger a native immune response, and studies are looking at how to enhance this defence. , at the cutting edge of future technologies is nanotech- nology, where tiny particles with attachments pass through leaky blood vessels into the tumour and deliver drugs lethal only to the tumour or deliver metallic particles that can then be exposed to infrared light to attack the cancer. dr linda spano died on september , , of ovar- ian cancer. dr michael brennan and dr linda spano, together with their families and many friends, have estab- lished the brennan/spano family foundation, which has a major interest in supporting research dedicated to the early detection and treatment of ovarian can- cer. for more information, contact the brennan/spano family foundation within the victoria foundation, - fort st, victoria, bc v w g , or visit www.victoriafoundation.bc.ca. the opinions expressed in commentaries are those of the authors. publication does not imply endorsement by the college of family physicians of canada. references . abenhaim ha, titus-ernstoff l, cramer dw. ovarian cancer risk in relation to medical visits, pelvic examinations and type of health care provider. cmaj ; ( ): - . doi: . /cmaj. . . us preventive services task force. genetic risk assessment and brca mutation testing for breast and ovarian cancer susceptibility: recommendation statement. ann intern med ; ( ): - . erratum in: ann intern med ; ( ): . . national institutes of health. prospective study of risk-reducing salpingo-oophorectomy and longitudinal ca- screening among women at increased genetic risk of ovarian cancer. protocol -c- . bethesda, md: national institutes of health; . available from: http://clinicalstudies.info. nih.gov/cgi/detail.cgi?a_ -c- .html. accessed apr . . smith lh, morris cr, yasmeen s, parikh-patel a, cress rd, romano ps. ovarian cancer: can we make the diagnosis earlier? cancer ; ( ): - . . berkenblit a, cannistra sa. advances in the management of epithelial ovarian cancer. j reprod med ; ( ): - . . goff ba, mandel ls, melancon ch, muntz hg. frequency of symptoms of ovarian cancer in women presenting to primary care clinics. jama ; ( ): - . . buys ss, partridge e, greene mh, prorok pc, reding d, riley tl, et al. ovarian cancer screening in the prostate, lung, colorectal and ovarian (plco) cancer screening trial: findings from the initial screen of a randomized trial. am j obstet gynecol ; ( ): - . . morice p, dubernard g, rey a, atallah d, pautier p, pomel c, et al. results of interval debulking surgery compared with primary debulking surgery in advanced stage ovarian cancer. j am coll surg : ( ): - . . bookman ma, greer be, ozols rf. optimal therapy of advanced ovarian cancer: carboplatin and paclitaxel vs. cisplatin and paclitaxel (gog ) and an update on gog -icon . int j gynecol cancer ; ( ): - . . moss c, kaye sb. ovarian cancer: progress and continuing controversies in management. eur j cancer ; ( ): - . . armstrong dk, bundy b, wenzel l, huang hq, baergen, lele s, et al. intraperitoneal cisplatin and paclitaxel in ovarian cancer. n engl j med ; ( ): - . . maugham ws. sheppey. london, engl: william heinemann; . . hirshberg c, barasch i. remarkable recovery. new york, ny: riverhead books; . . paley pj. angiogenesis in ovarian cancer: molecular pathology and therapeutic strategies. curr oncol rep ; ( ): - . . hortobagyi gn. trastuzumab in the treatment of breast cancer. n engl j med ; ( ): - . . see ht, kavanagh jj, hu w, bast rc. targeted therapy for ovarian cancer: cur- rent status and future prospects. int j gynecol cancer ; ( ): - . . hasan j, ton n, mullamitha s, clamp a, mcneilly a, marshall e, et al. phase ii trial of tamoxifen and goserlin in recurrent epithelial ovarian cancer. br j cancer ; ( ): - . . angus db, gordon ms, taylor c, natale rb, karlan b, mendelson ds, et al. phase clinical study of pertuzumab, a novel her dimerization inhibitor, in patients with advanced cancer. j clin oncol ; ( ): - . . blank sv, chang r, muggia f. epidermal growth factor receptor inhibitors for the treatment of epithelial ovarian cancer. oncology ; ( ): - . . halder j, kamat aa, landen cn jr, han ly, lutgendorf sk, lin yg, et al. focal adhesion kinase targeting using in vivo short interfering rna delivery in neutral liposomes for ovarian carcinoma therapy. clin cancer res : ( ): - . *editor’s note: the canadian partnership against cancer was announced in november by the government of canada. see www.partnershipagainstcancer.ca for more details. ifn institutet för näringslivsforskning - page could not be found. if you entered the url by yourself, check your spelling and try again. back to swedish startpage back to english startpage beauty treatment and spa design from islamic perspective procedia - social and behavioral sciences ( ) – - © published by elsevier ltd. selection and peer-review under responsibility of the centre for environment- behaviour studies (ce-bs), faculty of architecture, planning & surveying, universiti teknologi mara, malaysia doi: . /j.sbspro. . . ace-bs bangkok asean conference on environment-behaviour studies, bangkok, thailand, - july beauty treatment and spa design from islamic perspective rostam yaman*, zarina alias and norishahaini mohamed ishak faculty of architecture, planning and surveying,uitm shah alam, malaysia abstract the paper aims to study design and spatial relationship in health & beauty treatment by blending modern setting within islamic perspective. the chosen case studies are islamic spa in klang valley adopted islamic spa practice (isp). the methodology used is on-site observation and survey questionnaires. outcome from the research shown that respondents agreed and satisfied with the design aspect also the implementation of isp within the selected case studies. based on malaysia cases, it is imperative to apply and develop the design according to the isp as it is a flourishing tourism industries based on specific niche market. © published by elsevier ltd. selection and peer-review under responsibility of the centre for environment- behaviour studies (ce-bs), faculty of architecture, planning & surveying, universiti teknologi mara, malaysia keywords: beauty treatment/spa; space design; islamic spa practice; islamic perspective . introduction beauty salon or beauty parlor means a business dealing with cosmetic treatments for men and women which is from the hair to the toes. other variations of this type of business are including hair salons and spas. a beauty salon has become an almost iconic image in malaysian culture. it is a place where people go for beauty treatment and to purchase beauty product. a beauty salon is also a center for community news and confessions. each salon tries to have its own distinct identity and ambience. some cater to a particular section of the society, while others meet the demands of certain ethnic communities. * corresponding author. tel:+ - - ; fax:+ - - - . e-mail address: rosrose@salam.uitm.edu.my. available online at www.sciencedirect.com © published by elsevier ltd. selection and peer-review under responsibility of the centre for environment- behaviour studies (ce-bs), faculty of architecture, planning & surveying, universiti teknologi mara, malaysia rostam yaman et al. / procedia - social and behavioral sciences ( ) – today women are very much different than earlier time those women because most of them are working and their career nowadays same level as men. therefore, they are really giving emphasis to appearance, health, and pleasant personality. they are constantly looking to improve what they have or give themselves a whole new look start from the root of the hair to the tip of their toes. they drop by the nearest hair salon and spa to be pampered by stylists and beauticians to style their hair, massage their body, and get the manicure and pedicure treatment even using lots of cash, and an hour in a beauty salon every month. it is no wonder that hair salon and spa business remains one of the rapidly growing industries today. the successful hair salon and spa business is one that offers excellent service, use quality products, and provide an enjoyable atmosphere at an acceptable price. according to industry insiders, the growing popularity of day spas account for the increase in sales on the hair and salon industry. the rising demand for spa is related to the changing lifestyle that requires a person to relax, reflect, rejuvenate and rejoice oneself. segerberg, an international spa professional, elaborates that spa guests have the opportunity to take time to listen to their souls and bodies. malaysians are no exception. according to spa industry profile malaysia - , intelligent spas has identified spa numbers in malaysia have grown over % since , identifying spas currently operating and spas under development (clark, ). from the data, % were day spas and % were spas located in hotels, resorts or retreats which so called destination spas. the average indoor area of spa facilities in malaysia was square meters and contained . treatment room on average. % of spas owned a relaxation room compared to % that arranged access for their visitors to use a nearby relaxation room. whereas, herbal tea was the most common complimentary food or beverage item provided by spas, with % offering to visitors. besides, the increasing interest in traditional massage treatment was most current industry trend observed by spa owners and managers. in addition % of spa surveyed stated that there was increased customers awareness about spas. today beauty industries are very much different than earlier time. nowadays, most women are working and their career nowadays same level as men. therefore, they are really giving emphasis to appearance, health, and pleasant personality. they are constantly looking to improve what they have or give themselves a whole new look start from the root of the hair to the tip of their toes. they drop by the nearest hair salon and spa to be pampered by stylists and beauticians to style their hair, massage their body, and get the manicure and pedicure treatment even using lots of cash, and an hour in a beauty salon every month. it is no wonder that hair salon and spa business remains one of the rapidly growing industries today. the successful hair salon and spa business is one that offers excellent service, use quality products, and provide an enjoyable atmosphere at an acceptable price. according to industry insiders, the growing popularity of day spas account for the increase in sales on the hair and salon industry. however, to succeed as an industry is not an easy as there is many problems and difficulties to be overcome especially in islamic entrepreneur. in islamic basis, there are a lot of things to consider such as the using of beauty products either halal or non-halal and they should consider about the services offered meets the muslims needs. moreover, the important of islamic beauty salon and the difference between islamic and normal beauty salon is the design of the space planning itself which is closed and hidden from non-muhrim’s view. in addition, they must ensure that all their employees are women and better they hire muslim women employees as an al-quran said, islam does not forbid women to beautify themselves, but it must be moderate and does not exceed islamic limits. as the messenger of allah (pbuh) used to make this prayer: “oh allah! you made my appearance beautiful so make my conduct excellent.” malaysia holistic spa has its own specialties to offer in order to compete with neighbours like indonesia and thailand, and began to challenge them which they are now is dominating our local spa https://isiarticles.com/article/ untitled ar x iv :h ep -l at / v ju l psi-pr- - ucy-phy- / cern-th. / beautiful baryons from lattice qcd c. alexandroua, a. borrellib, s. güskenc, f. jegerlehnerb, k. schillingd,c, g. siegertc, r. sommerd a department of natural sciences, university of cyprus, nicosia, cyprus b paul scherrer institute, ch- villigen psi, switzerland c physics department, university of wuppertal d- wuppertal, ger- many d cern, theory division, ch- geneva- , switzerland abstract we perform a lattice study of heavy baryons, containing one (Λb) or two b-quarks (Ξb). using the quenched approximation we obtain for the mass of Λb mΛb = . ± . ± . gev. the mass splitting between the Λb and the b-meson is found to increase by about % if the light quark mass is varied from the chiral limit to the strange quark mass. work supported in part by dfg grant schi / - . http://arxiv.org/abs/hep-lat/ v introduction considerable progress has been achieved in the computation of low lying hadronic states from lattice qcd (lqcd). it turned out that quenched lqcd reproduces the hadron spectrum in the light quark sector surpris- ingly well, once finite volume corrections are carefully taken into account [ ]. this holds in particular for the ratio mn/mρ, which has been a notorious problem for lqcd over quite some years. beauty physics is attracting much attention because the origin of cp violation in the b-system is still an open question. the investigation of such a system is a great challenge to lqcd. considerable progress has been made in the lattice studies of heavy-light mesons like d- and b-mesons [ ]. heavy-light systems from the baryonic sector so far have been studied with lattice methods exploratively in the limit of infinite heavy quark mass [ , ]. throughout the current study the mass of the heavy quark has been kept finite. we will present results for the mass of Λb, a baryon composed of a b- quark and two light quarks, as well as for the mass of Ξb, a baryon composed of two b-quarks and one light quark. as in the case of heavy-light mesons, the most dangerous source of sys- tematic error stems from the fact that one is forced — in order to enter the region of heavy quark masses — to actually push the heavy mass close to the very limit of current lattice resolutions. we will attempt, however, to keep control on these effects of a finite lattice spacing a by a variety of precautions: . we avoid to compute the masses of the Λb and the Ξb directly, but rather calculate the mass splittings ∆Λ = mΛb − mb and ∆Ξ = mΞb − mb, with respect to the b-meson mass mb. these splittings do not depend on the heavy quark mass in the infinite mass limit and are therefore less prone to contamination by finite a effects in the b and c quark mass regions. . we monitor the dependence of the splittings on the lattice spacing for our three β values, β = . , . , . . this enables us (a) to check the assumption of weak a dependence and (b) to perform an a → extrapolation. . we will not calculate directly the mass splittings too close to the b quark mass. instead we stop the calculation at approximately twice the charm quark mass and then extrapolate our data to the b mass. moreover, we investigate finite size effects at β = . , on three lattices of spatial volumes , and , in lattice units. our lattice parameters are detailed in table . to obtain a good signal for the ground state, we use smeared gauge invariant interpolating quark fields [ ], defined for the standard wilson action. ns nt no. configs. β a mρ . . ± . . . . . ± . . . ± . table : lattice parameters: space and time extents ns and nt , number of configurations, β and the ρ-mass in lattice units. smearing techniques and volume effects for the reasons given above, we will compute the baryonic masses with refer- ence to the mass of the b-meson, by proper combinations that would elimi- nate the b-quark mass in the heavy quark limit. so we consider the splittings ∆Λ = mΛb −mb and ∆Ξ = mΞb − mb, respectively, in the single and double beauty sectors. in the first case, we need to compute the correlators, for the heavy-light pseudoscalar meson, cp (t) = ∑ ~x 〈( q̄(x)γ qj(x) ) ( q̄j( )γ q( ) )〉 , ( ) and for the Λ baryon [ ] cΛ(t) = ∑ ~x 〈( ǫabcqa(x) ( qjb (x)cγ q j c (x) )) ( ǫabcqa( ) ( qjb ( )cγ q j c ( ) ))† 〉 , ( ) where q(x) = q(~x, t) is the heavy quark field, and qj(x) = qj(~x, t) is the light one, to which smearing of type j [ ] has been applied . c is the charge the correlator for the Ξ is obtained from the one for the Λ, by replacing the light quark qj b by a heavy one qb. conjugation operator given by c = iγ γ . given the lattice results for these correlators, we perform a direct fit to their ratio rΛ(t) = cΛ(t) cp (t) → ae−∆Λt ( ) in the large t limit. it is by now well known that smearing [ , , ] is crucial to obtain a decent overlap of the operators with the ground state. in this work, we make use of the experience acquired previously while computing properties of the heavy- light pseudoscalar states [ ], where we found gauge-invariant ‘gaussian type’ wave functions (of r.m.s radius . fm) to provide sufficient overlap. the smearing was applied to the light quark source in the mesonic case. in this study, we are using precisely this procedure for the heavy-light baryons as well, without any further optimization. in order to establish ground state dominance we look for a plateau in the local mass of the ratio rΛ. in fig. a we show as an example the local mass of rΛ, for the two largest lattices: the solid line shows the fitted value for the plateau. fig. b shows the corresponding local mass for the ratio rΞ(t) = cΞ(t)/c p (t) used to determine ∆Ξ. these figures show the quality of the plateaus for representative κ values. worse quality is found only in a few cases, and it resulted in larger statistical errors; for instance the two largest κ values at β = . given in table . the pseudoscalar mass was extensively studied in ref. [ ] and the values have been taken from there. for checking the finite volume effects, we computed ∆Λ on three lattices with nt = , β = . and sizes ns = , , , for κl = . , and κh = . , . , . . we compare the results for the splitting in table . the values exhibit deviations of at most % . in fig. we plot the dimensionless ratio ∆Λ/mρ as a function of l, the lattice size in units of mρ; as can be seen, for these values of κh, the finite size effects of this ratio are smaller than our statistical errors. in the following, we will fix the volume to about fm (which corresponds to ns ≃ , and for β = . , . and . respectively) and carry out a detailed study of the extrapolation to the continuum limit. as a tribute to possible finite size effects we will add the above maximal variation of % as an uncertainty to all results. κl κh ∆Λ, × ∆Λ, × ∆Λ, × . . . ± . . ± . . ± . . . ± . . ± . . ± . . . ± . . ± . . ± . table : results for three different spatial lattice extents, ns = , , and , nt = , β = . . continuum limit Λ splitting. the results for ∆Λ at the three β values . , . and . at fixed volume are listed in table , all in lattice units. the extrapolations to u and s-type light quarks, — for given heavy quark κh — are performed as described in [ ]. since we are evaluating masses, it is natural to use mρ to set the lattice scale. the values of mρ for the various lattices have been listed in table ; the experimental value used is: mρ = mev. in fig. a we plot ∆Λ in gev extrapolated to the chiral limit as a function of /mp in gev − . within the statistical precision achieved in this compu- tation, the points show no dependence on a, although a is varied by about a factor two (cf. table ). in the continuum, the /mp expansion for ∆Λ gives ∆cont.Λ (mp ) = c + c mp + o(mp − ) . ( ) assuming no dependence on the lattice spacing, this form can be fitted directly to the points in fig. a yielding ∆Λb = ( ) mev at the mass of the b-meson. this result is included in the figure as the inverted triangle. the error bar of this point does not account for the fact that the simulation results exclude an a-dependence only within their precision. a realistic error that includes the uncertainty of extrapolating the lattice data to the continuum is obtained by allowing for the leading a-dependence at each value of mp [ ]: we start out from a selected value of mp (in physical units) and interpolate the lattice results from each (fixed) β-value to the value of mp . this enables us to compare ∆Λ at different values of a. a subsequent × , β = . κh a∆Λ a∆Λ(ms) a∆Ξ a∆Ξ(ms) ∆Λ(ms)/∆Λ(mu) . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . . ± . − . ± . . ± . × , β = . κh a∆Λ a∆Λ(ms) a∆Ξ a∆Ξ(ms) ∆Λ(ms)/∆Λ(mu) . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . . ± . − . ± . . ± . × , β = . κh a∆Λ a∆Λ(ms) a∆Ξ a∆Ξ(ms) ∆Λ(ms)/∆Λ(mu) . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . − . ± . − . ± . . ± . . . ± . . ± . . ± . − . ± . . ± . table : the mass splittings ∆Λ and ∆Ξ at the chiral limit and at the strange quark mass in lattice units for β = . , . , . . the last column gives the ratio ∆Λ(ms)/∆Λ(mu) for the same β values. linear extrapolation in a will then yield the continuum estimate for ∆Λ, at the chosen physical value of mp . reiteration of the procedure on a set of masses mp determines the nu- merical dependence of ∆cont.Λ on mp . in order to remain in compliance with the assumption of linearity in a, we used only a subset of the data listed in table , by excluding the data for the two heaviest masses at any value of β. a final fit of the continuum limit values ∆cont.Λ to eq.( ) yields ∆Λb = ± ± mev . ( ) here the first error is purely statistical and stems from a full jacknife analysis of our data. the second error represents the % uncertainty due to finite vol- ume effects. together with the known experimental value mb = . gev, we obtain an estimate for the mass of Λb : mΛb = . ± . ± . gev. ( ) we note in passing, that the parameter c is in agreement with the estimates obtained directly in the static approximation [ ], albeit within the larger uncertainties of the latter. in the same way we obtain the mass splitting ∆Λb(ms) where the light quark mass is extrapolated to the strange quark mass. the data fitted are shown in fig. b, and the result of the extrapolations described above is ∆Λb(ms) = ± ± mev , ( ) with the same meaning of errors. instead of looking directly at the splitting at the strange quark mass, one may consider the ratio r = ∆Λ(ms) ∆Λ(mu) , ( ) which is expected to have an even weaker a-dependence. indeed the ratio for the different β values shown in fig. c follows a “universal curve” with quite small statistical errors. a linear fit to the (weak) mass dependence yields r = . ± . ± . . ( ) this ratio represents the change in the Λb mass when replacing the u quark by an s quark. Ξ splitting. the mass splitting for the Ξ baryon is investigated using the same techniques as for the Λ. table displays the results after extrapolation of the light quark to the d and s mass respectively. we then convert all data to physical units, and plot ∆Ξ vs. /mp at the chiral limit in fig. . in this case the data show a statistically significant a-dependence, especially for heavy masses. we extrapolate to the continuum limit as above for pseudoscalar masses mp below the charm mass. we use the same ansatz as in the case of ∆Λ to fit the /mp dependence of ∆Ξ and obtain: ∆Ξb = − ± mev , ( ) this mass shift together with the experimental value for mb determines mΞb = . ± . gev , ( ) for the physical Ξb–mass. another possibility to compute the Ξb mass, is to consider the ratio r ′Ξ(t) = cΞ(t)/c h̄h p (t), which should yield the splitting between the Ξb mass and the Υ-meson mass. we evaluated this quantity but the resulting plateaus turned out to be of worse quality than those for the other chan- nel studied; this is due to the fact that smearing was applied only to light quarks, and so the heavy-heavy channels suffer from relevant contamination by higher-mass states. discussion the mass splitting technique is a viable method to compute the Λb mass on the lattice. both the lattice spacing dependence of the mass splitting and its dependence on the heavy quark mass are weak. thus an extrapolation to the continuum and to the b–quark mass is possible. our actual value of mΛb = ± ± mev can be compared to the value mev suggested by martin et al. within the naive quark model approach [ ]. experimentally, the determination of the Λb mass has a somewhat con- troversial history ever since [ ]. recently, the ua collaboration has measured the mass from events in the decay channel j/ΨΛ . their value it is an open question, why this decay channel has not been observed in the cdf experiment. is [ ] mΛb = ± ± mev. the delphi collaboration is presently quoting [ ] a preliminary mass value, mΛb = + − ± mev, which is based on one candidate event in the Λ+c π − and in the d pπ− decay modes. these numbers are in agreement with our result. for mΛc we obtain ± ± mev, which is in rough accord with the experimental value of mev [ ]. looking at the light quark dependence we found a % increase as we lift the quark mass from the chiral limit to the strange quark mass. finally, an estimate for the Ξb mass is given in eq.( ). our errors do include – as the dominant part – the uncertainty induced by an extrapolation to the continuum limit. nevertheless, it is desirable to further check these extrapolations through simulations with higher lattice resolutions and/or different lattice actions. acknowledgements we thank the personal at the computer centers cscs in manno switzerland and jülich, germany for their support. ks thanks a. martin for a valuable discussion. references [ ] f. butler, h. chen, j. sexton, a. vaccarino and d. weingarten, ibm- report (hep-lat- ) [ ] see e.g. c. bernard in lattice nucl. phys. b (proc. suppl.) ( ) ; r. sommer,beauty physics in lattice gauge theory, preprint desy - , to be published in physics reports c. [ ] c. alexandrou, s. güsken, f. jegerlehner, k. schilling, and r. sommer, nucl. phys. b ( ) . [ ] a. martin and j.m. richard, phys.lett. b ( ) . [ ] s.güsken, in lattice , nucl. phys. b (proc. suppl.) ( ) [ ] m. bochicchio, g. martinelli, c. r. allton, c. t. sachrajda and d. b. carpenter, nucl. phys. b ( ) [ ] a. duncan, e. eichten and h. thacker, nucl. phys. b (proc. supp.) ( ) . [ ] ukqcd collaboration, s. collins et al., nucl. phys. b (proc. supp.) ( ) . [ ] c. alexandrou, s. güsken, f. jegerlehner, k. schilling, g. siegert and r. sommer, desy preprint - , z. phys. c in press. [ ] s. aoki et al., nucl. phys. b (proc. suppl.) ( ) . [ ] c. alexandrou, s. güsken, f. jegerlehner, k. schilling, and r. sommer, nucl. phys. b ( ) . [ ] particle data group, k. hikasa et al., phys. rev. d ( ) . [ ] c. albajar et al., ua collaboration, phys. lett. b ( ) . [ ] m. battaglia et al., delphi collaboration, delphi note delphi - phys , march . figure captions figure a the ∆Λ local masses, given by µ loc Λ (t) = log[ rΛ(t−a) rΛ(t) ] for κl = . , κh = . at β = . , for a × lattice, and for κl = . , κh = . at β = . , for a × lattice. figure b the same as figure a, but for µlocΞ (t) = log[ rΞ(t−a) rΞ(t) ]. figure ∆Λ/mρ is shown vs l for three heavy quark masses at β = . . the light quark mass was fixed to about twice the strange quark mass. figure a the Λ mass splitting is shown vs /mp in gev − at the chiral limit. the solid line is a global fit assuming no a effects. it gives the value shown with the inverted triangle at the b-meson mass. the value ob- tained after extrapolation to the continuum limit and to the b-meson mass, is shown by the open circle. this extrapolation is discussed in the text. figure b as for figure a but at the strange quark mass. figure c the ratio ∆Λ(ms)/∆Λ(mu) is shown vs /mp . the notation is the same as for figure a. figure the Ξ mass splitting, ∆Ξ = mΞ − mp is shown vs /mp in gev − at the chiral limit. the notation is the same as for figure a. this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v this figure "fig - .png" is available in "png" format from: http://arxiv.org/ps/hep-lat/ v http://arxiv.org/ps/hep-lat/ v double dental prize success two researchers from barts and the london, queen mary’s school of medicine and dentistry have won the international association for dental research’s (iadr) hatton prize. dr maria nystrom of the institute of cancer won the senior prize for her phd research into oral cancer. her group showed that non-steroidal anti-inflammatory drugs (nsaids) block invasion of oral cancer cells by inhibiting the function of an important ‘cell adhesion molecule’, the αvβ integrin, which is over expressed in oral cancer. the junior prize was won by dr jonathan collier of the institute of cell and molecular science for research also into oral cancer. it looked at the expression of chemokine receptors on the surface of oral cancer cells. the iadr seeks to advance research and increase knowledge for the improvement of oral health worldwide. its annual hatton prize is sponsored by unilever and the awards were presented during the iadr’s th general session in brisbane, australia, at the end of june, . pictured left to right, yoshiro takano, hatton committee chairman, dr jonathan collier, dr maria nystrom and takayuki kuroda, president, iadr. news the bdj news section accepts items that include general news, latest research and diary events that interest our readers. press releases or articles may be edited, and should include a colour photograph if possible. please direct your correspondence to the news editor, arveen bajaj at the bdj, the macmillan building, crinan street, london n xw or by email to bdj@bda.org british dental journal volume no. aug dentists gain incorporation status dentists can now own their own com- panies for the first time in fifty years due to new regulations which came into force on the july. after four years of lobbying, section of the dentist act is to be removed and dentists can have incorporation status. they will be able to set up as a limited company or as a limited liability partnership (llp). dentists will be able to limit liabili- ties, have shareholders (including their spouse or staff), raise capital from out- side to purchase new premises or dental equipment and keep ownership of the business separate from the manage- ment. incorporation will mean protec- tion of personal assets and the option to bring other dental professionals into practice management. future retirement planning may be easier and practices will be allowed to grow substantially. if they become a limited company, the current professional indemnity cover they have will no longer be valid and professional indemnity cover for the new company will need to be arranged. andy parry, a dentist from integrat- ed dental holdings in oswaldtwistle, recently raised almost £ , on com- pletion of the london marathon earlier this year. andy, a -year-old diabetic raised the cash for two key charities, the royal air force benevolent fund and derian house childrens hospice. race for charity d i a r y september moving to private practice venue: the midland hotel, manchester date: september www.bda-events.org the british society of paediatric dentistry annual scientific conference ‘the art & the science’ venue: the hilton, leeds city date: - september www.bspd.co.uk/conf- .html european society for oral laser applications/ hellenic society for oral laser applications st mediterranean laser congress venue: hilton hotel rhodes resort, greece date: - september email: esola @medacad.org www.esola.at fdi annual world dental congress venue: shenzhen, china date: - september email: congress@fdiworldental.org www.fdiworldental.org october preparing for retirement venue: cedar court hotel, harrogate date: october www.bda-events.org community dental services group annual presidential and scientific meeting venue: marriott forest of arden hotel, birmingham date: - october www.bda-events.org the american dental association (ada) th ada annual scientific session and marketplace exhibition venue: mandalay bay resort and convention center, las vegas date: – october www.ada.org hospitals group annual presidential and scientific meeting venue: portmeirion, north wales date: - october www.bda-events.or november british academy of cosmetic dentistry’s (bacd) nd annual conference venue: britannia international hotel, london date: - - november email: info@bacd.com www.bacd.com british dental journal volume no. aug dental schools need more funding uk dental schools are providing sound training for the dentists of tomorrow, but many are in need of a major upgrade, according to a new report from the gen- eral dental council (gdc). around new dentists graduate from uk dental schools every year. this month, the gdc has published the general report on its lat- est round of quality assurance visits to the schools. the report highlights the gdc’s key findings and provides a snapshot of the current state of uk undergraduate dental education. it identifies examples of good educational practice at the uk’s dental schools and also makes recommendations for further developing the delivery of den- tal education. a gdc inspection panel visited all dental schools in the uk between october and july . the panel’s job was to check that gdc standards for training future dentists, as set out in its guidance document the first five years, are being implemented. the inspectors looked at the undergraduate dental programme and also the running of the final examination at each school. they met academic and clini- cal staff and dental students, and looked at the provision of clinical and educational facilities. the inspectors found that all uk dental schools are, on the whole, meet- ing the gdc’s expectations of under- graduate dental education. the report emphasises and welcomes the high level of commitment evident amongst dental school staff, the opportunities outreach teaching is giving dental students to treat patients in a general practice setting, and the high quality student support systems in place at all schools. however, the report also highlights some areas of serious concern. the inspec- tors warn that there is an urgent need for substantial additional funding if high quality dental training is to be sustained. in particular, they found that many dental teaching hospitals are in need of a major upgrade, and greater investment is needed in academic staffing to ensure there is a sufficient complement of teachers to deliv- er the training programmes. the gdc is calling on the departments of health, the higher education funding councils, nhs agencies, and others with a role in support- ing dental education, to address these con- cerns as a matter of urgency. new statutory register opens for dental nurses and dental technicians last month saw the opening of a new stat- utory register for dental care profession- als (dcps) practising in the uk. dentists, dental hygienists and dental therapists are already registered with the gdc and now, other professionals who play a role in patients’ dental care, including dental nurses and dental technicians, will join the gdc’s registers. registration means that dental professionals have met educa- tional standards and that they are profes- sionally accountable for their actions. a survey conducted by the gdc found that % of adults in the uk believe that dental nurses currently need to be regis- tered with a regulatory body before they can practise. on being told that dental nurses did not need to be registered, two- thirds ( %) of adults thought that dental nurses should be. british dental journal volume no. aug home oral hygiene works says study researchers have found that gingi- val bleeding and halitosis were greatly reduced after a two-week oral hygiene programme of dental flossing and tooth brushing. the list of excuses for not brushing or flossing is endless, but according to a new study published in the journal of periodontology, these are two tasks that should not be omitted from the daily hygiene routine. in the study, fifty-one sets of twins between the ages of and years of age were examined for gingival bleed- ing and halitosis. each set of twins was then divided into two groups. one group of twins manually brushed their teeth and tongue twice a day for two weeks. the second group of twins was given the same instructions in addition to using dental floss twice a day. after two weeks, the twins were examined again for gingi- val bleeding and halitosis. twins were examined in this study because each individual set shares the same environmental factors such as dietary habits, health and life practices, thereby constituting a perfect case-con- trol matched study. researchers found that tongue and tooth brushing in combination with dental flossing significantly decreased gingival bleeding by % after a two- week oral hygiene programme. halitosis was also reduced. in the group that did not floss as part of their daily routine, gingival bleeding sites increased by almost %. “gingival bleeding and halitosis is often the first sign of poor oral hygiene that may eventually lead to further peri- odontal problems,” said walter a. bretz, department of cariology and compre- hensive care, new york university col- lege of dentistry. “a good way to prevent periodontal disease and tooth decay is through at-home oral hygiene care and routine dental visits.” runners raise cash for kids diamond smiles dental centre in barnoldswick, east lancashire, has raised £ , for clic sargent, a charity for children living with cancer by running the great manchester run on may . practice owner adam evans, associate dentist richard parker, practice manager michelle hudson and dental nurses donna cooper, julie hayton and alex stobbs all took part. pictured, the runners present their cheque to helen relihan from clic sargent. swamy rectangle newsnews british dental journal volume no. aug an image of an oral bacterium was amongst a number of stunning images honoured at the wellcome trust bio- medical image awards . other win- ning images included the blind spot of an eye, the stinging hairs on a nettle leaf and cancerous cells. the image, actinobacillus actino- mycetemcomitans was captured by derren ready from the eastman dental institute, london. the winning images were selected from those submitted to the medi- cal photographic library over the past twelve months. this collection of over , images covers modern medi- cine and biomedical science, the history of medicine and the history of human culture from the earliest periods of civi- lization to the present day, reflecting the diversity of the interests of sir henry wellcome. presenting the awards, scientist and broadcaster kathy sykes described the award winners as “a stunning collection of images that portray a range of sur- prises, intrigues, beauties and even hor- rors of biomedical science.” other images recognised in the awards ceremony include human colon cancer cells, taken by dave mccarthy and annie cavanagh from the uni- versity of london school of pharmacy and squamous cell carcinoma, taken by anne weston from cancer research uk. the latter shows a cell from the second most common form of skin cancer, fro- zen and split open to reveal its nucleus, an aggressive, beast-like cell. the award winning images are on display at the wellcome library, euston rd, london, along with audio clips of the scientists behind the images discussing their work. entrance to the exhibition is free. they can also be viewed online at www. wellcome.ac.uk/bia . review on exam for overseas dentists the international qualifying examination (iqe) may be replaced with a new stream- lined exam, according to the general den- tal council (gdc). it is calling for views on its proposal for a new exam to assess the competence of dentists from outside the european economic area (eea) who wish to practise in the uk. the iqe has come under increasing strain due to the large influx of dentists from overseas and the limit on places dental schools, which host the exam. at present, dentists from outside the eea sit the iqe and those who pass can apply for registration to practise unsuper- vised on patients in the uk. after five years of the iqe, the gdc is carrying out a com- prehensive review of how it assesses the competence of an overseas dentist for uk practice. the aim of the review is to ensure the gdc’s processes are in step with devel- opments in assessment techniques and that they are fulfilling their public protection purpose. a review group is proposing that the current iqe is replaced with a new exam to assess the clinical skills and knowledge of overseas dentists. this streamlined exam would differ significantly from the iqe and would make use of modern assessment methods to ensure a robust and fair test for dentists. the exam will also be better able to cope with fluctuations in demand than the current iqe, more practicable for the exam centres to hold and will keep waiting times for candidates to a minimum. key differences from the current exam would be a two-part rather than a three-part exam, the introduction of an objective structured clinical examination (osce) and testing of candidates’ technical skills in updated den- tal manikin exercises, not on real patients. the consultation document is available on the gdc website www.gdc-uk.org and the closing date for responses is friday octo- ber . the beauty of the molecular world image courtesy of the wellcome trust cancer research uk scientists have dis- covered mouth cancer can develop along two distinct pathways, an aggressive or less aggressive route, reveals a study pub- lished in cancer research this month. the research lays the foundations for further studies that could help to improve the management of pre-cancerous lesions and possibly prevent the development of the disease in the future. the researchers from cancer research uk’s beatson institute for cancer research in glasgow took samples from the mouths of people with pre-can- cerous lesions, or spots, patients with mouth cancer and four normal mouths. they compared these samples, each one made up from thousands of cells, in an attempt to find out if the disease develops in more than one way. the researchers identified two differ- ent routes by which mouth cancer devel- ops, resulting in ‘mortal’ and ‘immortal’ tumour cells when they are grown in the laboratory. ‘mortal’ and ‘immortal’ cells are genetically very different. ‘mortal’ cells have a limited lifespan and so will exhaust themselves as they develop into a tumour, being less likely to spread or recur following treatment. ‘immortal’ cells on the other hand are much more resilient and will keep on dividing, mak- ing them more likely to spread and to cause a recurrence - a major characteris- tic of aggressive disease. they found that faults in the p gene and missing expression of the p gene were closely associated with ‘immortal’, aggressive tumours. importantly, these same changes were also found in pre- cancerous cells, which grew in labora- tory cultures as ‘immortal’ cells. when it is working normally, the p gene stops damaged cells dividing and should stop cancers growing, which is probably why faults were found in the p gene in ‘immortal’ cells rather than in ‘mortal’ ones. the p gene helps to control the cell regulation process and can prevent cancer from developing - expression of this was missing from most of the more aggressive mouth cancer cells. mouth cancer breakthrough review on exam for overseas dentists there are several criticisms that can be made of this collection. most curiously, the essays are not attributed to their original context, nor are their first dates of publication given. thus deracinated, they lose some of their cutting edge, which – as with all of pollock’s work – is crucial to a sense of her ‘analytic awareness of the major concerns of the feminism of [her] time, the marxism of [her] time, the art history of [her] time’ (p. ). for readers like myself who are familiar with pollock’s work this is frustrating, and invites a game of ‘check the sources’; for those unfamiliar with pollock’s output, it gives no sense of the diversity of her many interventions into contemporary art criticism and art history. likewise, the absence of an index or bibliography makes it hard to track various lines of thought to their sources – and for a specialist arts publisher, the quality of design, production and illustration are disappointing indeed! rosemary betterton references harris, j. ( ) the new art history: a critical introduction, london & new york: routledge. pollock, g. ( ) avant-garde gambits – : gender and the colour of art history, london: thames & hudson. pollock, g. ( ) editor, generations and geographies in the visual arts: feminist readings, london & new york: routledge. pollock, g. and orton, f. ( ) editors, avant-gardes and partisans reviewed, manchester: manchester university press. pollock, g. ( ) differencing the canon: feminist desire and the writing of art’s histories, london & new york: routledge. doi: . /palgrave.fr. beauty matters peg zeglin brand (editor); university of indiana press, bloomington and indianapolis, , out of print (isbn - - - ) hbk, pp, pbk isbn d . beauty matters has received well-earned attention from aestheticians. peg brand has assembled essays that represent both artistic and cultural diversity. in so doing, she has helped to extend a problem of great importance in philosophical aesthetics and art criticism to feminist theory and cultural studies. in the early th century, the concept of beauty came under fire from various philosophers who regarded beauty as a philosophical fiction, and from various conceptual artists who considered beauty a political construct. art, in this climate, had only social or book reviews feminist review personal significance. this view was to colour the artworld for much of the century, despite many renegade movements, such as abstract expressionism and formalist criticism. this tendency has lost its verve over the last years or so as beauty came to be seen as indispensable if we are to understand human experience in its complexity. in brand’s ‘introduction’ she discusses the peregrinations of beauty through the history of philosophy and, especially the th century. she suggests that the traditional standards undergirding our aesthetic responses to artworks and our erotic and affective reactions to people (both self and other) have been conditioned by the male gaze. this, of course, is not a novel idea. brand does, however, offer much that is new in her introduction and in her very choice of essays. she argues that to acknowledge the reality of beauty is not to return to a transcendent platonic ideal or to the romantic (male) sublime. beauty, she tells us, is edgy and dangerous, as artists like mappelthorpe, serrano, and cindy sherman show us, working as they do at the razor’s edge of genre, style, and subject matter. the book offers essays on philosophical aesthetics, body art, ballet, personal beauty, eroticism in the visual image, representations of disability in art, the use of art to experience transexuality, the representations of race and ethnicity, and brand’s interview with the radical performance artist orlan. one thing common to all of the essays, though, is the interest in showing how our reactions to things as beautiful or ugly are enmeshed in our moral beliefs. marcia eaton, in the book’s lead article, her ‘kantian and contextual beauty’ defends the primacy of this ‘contextual’ notion over the perennially alluring, kantian, nonethical view of beauty. each article demonstrates this thesis from a different perspective. to look at a few examples, sally banes, in her ‘a new kind of beauty: from classicism to karole armitage’s early ballets’ brings to light the neo-classical, renaissance world view and ideals of feminine beauty presupposed by basic elements of classical ballet: verticality (political hierarchies, social nobility, and spiritual uprightness), the turn out of the body (openness to others, to light, to truth), and pointe work of the female dancer (an equilibrium beyond nature, the ethereality of feminine beauty). banes then explains how armitage’s work challenges traditional social values by highlighting the eroticism and ironic potential of the canonical elements and by making ballet, with its strict gender roles, one of the subjects of her work itself. dawn perlmutter’s ‘miss america: whose ideal?’ reveals the deplorable political assumptions in the selection of the beauty queen and the cultural havoc these views have wrought. from an eastern perspective, eva kit wah man, in her ‘female bodily aesthetics, politics, and feminine ideals of beauty in china’ analyzes the contemporary, communist chinese ideal of feminine beauty by tracing the feminine ideal through confucianism and taoism and then exploring the complex moral and aesthetic terrain of the courtesan in late imperial china. feminist review book reviews in ‘from the cooked timber of humanity’ philosopher anita silvers considers why we can find beautiful a representation of disability or anatomical anomaly (e.g., picasso’s ‘maya with a doll’) and yet avert our eyes from the same human trait when we encounter it in life. silvers argues that disability is the binary opposite against which the normal is defined. she thus recommends that in our efforts to broaden our standards of beauty, we view those who are physically different as deepening our insight into humanity just as a distinctive artwork can deepen our comprehension of art. noel carroll, in his ‘ethnicity, race, and monstrosity’ focuses on ugliness, especially in horror and humor, both of which he contends are ‘rhetoric[s] of hatred’ that betray racial and moral prejudices. as for racial and sexual stereotypes, paul c. taylor challenges philosophical aesthetics arguing that it should focus less on art and more on human bodily beauty, and that it should be primarily cultural criticism rather than philosophy of art. arthur danto responds to taylor sympathetically but with a forceful defense of aesthetics. the other articles treat various topics: kathleen higgins contrasts real beauty of persons with its imitators, flawlessness and glamour; susan bordo discusses beauty in the image of the male body; hilary robinson examines luce irigaray’s views; kaori chino explores the haunting photographic self-portraits of yasumasa morimura, a male who impersonates legendary movie actresses. brand has put together a varied array of high-quality essays. this excellent anthology will appeal to specialists in aesthetics, the arts, feminism, and cultural theory. carol s. gould doi: . /palgrave.fr. the great arizona orphan abduction linda gordon; harvard university press, cambridge, ma, london, england, , pp, hbk isbn - - - d . linda gordon has achieved that unusual position of writing a highly scholarly book (winner of the bancroft and american historical association prizes) which has also enjoyed success with a general readership. the accessibility of this text is largely attained through a distinctive narrative strategy, interspersing chapters on the wider historical context with a detailed narrative of the unfolding crisis over orphan adoption in a small arizona anglo-mexican mining community. historical analysis is interwoven with the drama of a highly emotive confrontation in which race, gender and class identities play out within the charged atmosphere of attempted inter-racial adoption. book reviews feminist review beauty matters microbiology and molecular biology reviews, june , p. – vol. , no. - / /$ . � doi: . /mmbr. . . – . copyright © , american society for microbiology. all rights reserved. “sleeping beauty”: quiescence in saccharomyces cerevisiae† joseph v. gray, * gregory a. petsko, gerald c. johnston, dagmar ringe, richard a. singer, and margaret werner-washburne division of molecular genetics, faculty of biomedical and life sciences, university of glasgow, glasgow g nu, united kingdom ; rosenstiel basic medical sciences research center, brandeis university, waltham, massachusetts - ; department of microbiology and immunology and department of biochemistry and molecular biology, dalhousie university, halifax, nova scotia b h x , canada; and biology department, university of new mexico, albuquerque, new mexico introduction ....................................................................................................................................................... quiescence in yeast......................................................................................................................................... operational definition of quiescence .................................................................................................................. characteristics of quiescent cells ....................................................................................................................... cell quiescence cycle............................................................................................................................................. mutants defective in the cell quiescence cycle ................................................................................................ entry into quiescence .................................................................................................................................. tor pathway .......................................................................................................................................................... protein kinase c pathway..................................................................................................................................... protein kinase a pathway ..................................................................................................................................... snf p pathway ......................................................................................................................................................... an emerging signaling network .......................................................................................................................... working model for the regulation of entry into quiescence .......................................................................... maintenance of viability in quiescence ........................................................................................... genes required for maintaining viability .......................................................................................................... “essential” genes that are not required for viability ................................................................................... control of gene expression .................................................................................................................................. translation............................................................................................................................................................... protein turnover and covalent modification of n termini............................................................................. autophagy ................................................................................................................................................................ metabolism .............................................................................................................................................................. redox homeostasis ................................................................................................................................................. aging versus maintenance of viability ................................................................................................................ exiting from quiescence............................................................................................................................. sensing nutrients ................................................................................................................................................... transcriptional changes........................................................................................................................................ proteome changes .................................................................................................................................................. exit mutants............................................................................................................................................................ gcs and vesicular traffic .................................................................................................................................... conclusions and perspectives................................................................................................................. acknowledgments ........................................................................................................................................... references ............................................................................................................................................................ “beloved, may your sleep be sound that have found it where you fed” william butler yeats (lullaby) introduction all living cells appear to be capable of exiting the normal cell cycle (proliferating state) and entering an alternative (resting) state termed quiescence or g( ). quiescent microbes are thought to represent about % of the biomass on earth and are doubtless the seeds of microbial life in nature. further- more, most eukaryotic cells, whether they exist as single-celled or multicellular organisms, spend the majority of their natural lives in a quiescent state ( ). quiescent cells of both prokary- otic and eukaryotic microorganisms can survive for long peri- ods—sometimes years—without added nutrients, a feat of as- tonishing resilience ( ). beyond contributing to a more rounded view of the life cycle of cells, understanding quiescence has other potentially signif- icant implications. a deeper understanding of the conserved mechanisms underlying entry into, survival in, and exit from quiescence in eukaryotes may aid the development of novel or supplementary immunosuppressants and anticancer therapies and is also likely to provide significant insights into such di- * corresponding author. mailing address: division of molecular genetics, faculty of biomedical and life sciences, university of glas- gow, anderson college, dumbarton rd., glasgow g nu, united kingdom. phone: ( ) - - / . fax: ( ) - - . e-mail: j.gray@bio.gla.ac.uk. † this paper is dedicated to the memory of ira herskowitz and helmut ruis. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ verse processes as aging ( ) and neurodegenerative diseases ( ). the discovery of variations on a common theme may allow the development of novel antipathogenic agents. fur- ther, most of the world’s microorganisms have yet to be cul- tured. among these organisms are likely to be many novel microbes, predominantly in a quiescent state, that can produce medically useful natural products or whose study will provide new insight into evolution, development, and ecology. an un- derstanding of how to stimulate these microbes to exit from quiescence may aid the culturing of such organisms. although we ultimately seek to understand aspects of qui- escence shared among all eukaryotes, we focus this review on quiescence in the budding yeast saccharomyces cerevisiae. we restrict our focus for several reasons. first, s. cerevisiae is one of the best-studied eukaryotes and is tractable to all levels of experimental analysis. second, because of the conservation of basic cellular processes among eukaryotes, the study of quies- cence in yeast is likely to illuminate the equivalent mechanisms and states in many if not all other eukaryotes and possibly prokaryotes as well. indeed, even mammals possess orthologs of the apparent yeast regulators (see below), such as the tors, protein kinases a and c, and snf p. this is not surprising. the ability of microbes and our microbial ancestors to enter qui- escence and thereby maintain viability when starved is likely to have been essential to their survival. a strong selective pres- sure has doubtless acted to maintain the ability to enter into, survive in, and exit from quiescence over evolutionary time. third, quiescent yeast and quiescent mammalian cells share a number of salient characteristics such as unreplicated genomes ( ); characteristically condensed chromosomes ( ), re- ferred to as g( ) chromosomes; increased rates of autophagy; and reduced rates of translation (see below for details). fur- thermore, both yeast and mammalian cells respond similarly to rapamycin, an immunosuppressant drug for humans, which inhibits the proliferation of both yeast and mammalian cells and drives each into a state similar to their respective quiescent state ( ). even though entry of cells into and exit of cells from quiescence in metazoan bodies is normally regulated by positional and developmental cues, mammalian cells share with yeast cells the ability to respond to starvation by entering quiescence-like states ( ). finally, with the exploitation of the genome sequence, the new technologies available to study yeast further ensures that this small eukaryote will be central to unlocking the secrets of the quiescent state. our knowledge of quiescence in any organism including yeast is fragmented, and the mechanisms that regulate entry into, maintenance of, and exit from quiescence are, at best, poorly understood. historically, one major factor limiting the study of quiescent cells has been their very modest life-style: classical cell biological, physiological, and biochemical assays detected little or no activity in these cells. furthermore, the application of genetics to the study of quiescence has been limited (see below for further considerations of this point). as a result, many researchers have long suspected that quiescent cells are difficult to study (historically correct), do not repre- sent a distinct phase of cell (probably inaccurate), do not do anything (inaccurate), or are either uninteresting or dead (very inaccurate). even now, understanding the mechanisms by which a cell transits between the proliferating and quiescent states and the way in which these states differ presents a for- midable challenge. as we shall argue, switching between active proliferation and quiescence is likely to involve the wholesale reprogramming of regulatory networks and the remodeling of most if not all intracellular structures and processes. the “holy grail” for researchers working on quiescence is to define a core quiescence program that prevents cell growth and proliferation, that confers on cells the ability to survive better under adverse conditions, and that allows a rapid transition back to the proliferating state when conditions again become favorable. here, as a starting point, we present an overview of the current understanding of quiescence in yeast. almost papers dealing with some aspect of quiescence in yeast have been published since our last major review of this topic ( , ). we cannot completely cover this literature, but we provide a list of all the papers that we identified in this area on our website (http://biology.unm.edu/biology/maggieww /spreview.htm). some literature not covered herein has been discussed in another recent and shorter review of stationary- phase yeast cultures, i.e., those containing quiescent cells ( ). quiescence in yeast operational definition of quiescence quiescent yeast cells are commonly obtained in the labora- tory by growing liquid cultures to saturation in rich media, usually for to days at °c (fig. ). the term “stationary phase” has been used to describe the state of saturated liquid cultures and the state of the constituent cells. we propose a revision of this nomenclature, such that “stationary phase” is used to refer to the state of a saturated culture and the term “quiescence” is used to refer to the state of the constituent cells in such a saturated culture (fig. ). it is not known if all cells in a stationary-phase culture are quiescent, but we assume that a substantial proportion are, including the daughter cells that were produced during the final doublings in the post- diauxic phase of culture growth. we currently define the reference quiescent state in yeast as the state of the cell brought about by growth of a liquid culture of cells to saturation in rich media (yeast-peptone-dextrose [ypd]). once this and other quiescence-like states of yeast have been more closely examined and compared, this defini- tion of quiescence will doubtless become more refined. the path by which such a culture of cells reaches saturation is not simple (fig. ). initially, the constituent cells derive their energy from fermentation, the process by which glucose is preferentially metabolized via glycolysis to form nonferment- able carbon compounds, particularly ethanol. during the ex- ponential or logarithmic growth phase, the culture grows rap- idly (and the constituent cells proliferate with an average doubling time of approximately min at °c) until glucose is exhausted in the medium. at this point, termed the diauxic shift, the culture ceases rapid growth while the constituent cells readjust their metabolism to utilize the nonfermentable carbon sources still present in the medium. after the diauxic shift, the cells in the culture undergo one or two very slow doublings over a period of days before finally ceasing proliferation after the depletion of ethanol and other nonfermentable carbon sources ( ). at this point, the culture is in stationary phase and most, if not all, of the constituent cells are quiescent ( ). gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ all cultures having passed the diauxic shift are often (mis- takenly, we believe) classified as being in stationary phase and the constituent cells thus in quiescence. we favor drawing a clear distinction between cells found in the post-diauxic shift state of a culture prior to saturation and quiescent cells found in a saturated culture. this distinction may be more than se- mantic: post-diauxic shift cells have acquired many, but not all, of the characteristics of quiescent cells and continue to prolif- erate, albeit very slowly. entry of cells into quiescence is best viewed as a stepwise process in liquid culture, with various characteristics of the quiescent state acquired either at the diauxic shift or on final cessation of proliferation (see below). although our operational definition of quiescence (the state of cells in liquid cultures grown to saturation in rich media) focuses attention on a specific reference state, the definition may be overly restrictive. it is clear that many of the cells in a colony growing on the surface of solid rich media are also in quiescence ( ). however, because of the immobility of yeast cells on solid surfaces, distinct microenvironments develop within a colony, allowing multiple subpopulations of cells to coexist. this is in stark contrast to a culture of cells in agitated liquid medium, where every cell experiences the same, homo- geneous environment. the response of a colony of cells to starvation is thus likely to be significantly more complicated than, although closely related to, that of cells in liquid cultures. our operational definition of quiescence may also be overly restrictive because yeast cells enter somewhat stable nonpro- liferating states when rapidly starved for nitrogen, sulfur, or phosphate or when transferred directly to water ( ). indeed, spores, formed when diploid cells are starved for nitrogen in the presence of a poor carbon source, are also in a quiescence- like state: they can remain viable for many years—possibly centuries ( ). because the relationships between these “other” nonproliferating cell states and quiescence are not yet known, we do not discuss these states further here. it should be noted that not all starvations cause entry into viable nonproliferating states. for example, starvation of ino- sitol auxotrophs for inositol causes rapid cell death (“inositol- less death”), apparently by disrupting the ordered growth of the cell ( ). in addition, most laboratory strains lose viability relatively quickly when grown to saturation in synthetic, de- fined medium ( ). it thus appears that entry into quiescence (and quiescence-like states) is a programmed response to spe- cific environmental changes and does not occur simply by de- fault. characteristics of quiescent cells the relationship between the state we term quiescence or g( ) in yeast and the so-called g( ) state of nonproliferating, terminally differentiated mammalian cells such as neurons and fibroblasts remains to be established, but it is likely that qui- escent yeast will prove to be an important model for under- standing the g( ) state of multicellular eukaryotes, as it has been for so many aspects of the proliferative cell division cycle. quiescent yeast cells display numerous specific characteris- tics that differentiate them from proliferating cells: they do not proliferate; they fail to accumulate mass and volume; they are arrested as unbudded cells ( ); the overall transcription rate is three to five times lower than in logarithmic-phase cultures ( ); they have a requirement for translation from internal initiation sites (internal ribosome entry site) ( ); expression of a subset of genes is severely repressed, e.g., those encoding ribosomal proteins; expression of a subset of genes is strongly induced, e.g., snz , hsp , and ubi ( ); mrna degra- dation is inhibited ( ); overall protein synthesis is reduced to approximately . % of the rate found in logarithmically grow- ing cultures ( ); chromosomes are condensed [g( ) chromo- somes, ( )]; autophagy (the process of engulfment of the cytoplasm into lipid vesicles for delivery to the vacuole for degradation) is induced ( ); cells develop thickened cell walls and are more resistant than are proliferating cells to digestion by zymolyase and to treatment with certain toxic drugs ( ); and cells are more thermotolerant and osmotoler- ant than are their proliferating counterparts ( ). perhaps surprisingly, quiescent yeast cells are capable of responding to environmental signals in addition to the pres- ence of carbon. irradiation, heat shock, and treatment with chemicals such as methylmethane sulfonic acid and certain toxins can induce the expression of similar genes in both qui- escent and proliferating yeast ( ) (m. werner-washburne, unpublished data), as can oxidative stress ( ). the above characteristics begin to define a set of landmarks that can be used to identify and characterize cells in quiescence and suggest that the quiescent and proliferating states are distinct. furthermore, a variety of mutants, including ubi , ard , and some alleles of bcy , are known to selectively or specifically die when starved, supporting the notion that the proliferating and quiescent states are distinct. however, per- haps the most compelling argument that quiescence should be fig. . relationship between the state of a culture of yeast cells growing to saturation in rich medium (ypd) and the state of the constituent cells. when yeast cells are inoculated into rich medium containing glucose, the cells proliferate rapidly using fermentation and the density of the culture (reflected in optical density at nm [od ]) increases logarithmically with time (log phase). when glu- cose is consumed in the culture at the diauxic shift (after approximately day), the cells cease rapid cell proliferation and readjust their me- tabolism from fermentation to respiration to utilize other carbon sources present in the medium. in the resulting post-diauxic shift state of the culture, constituent cells proliferate very slowly. when external carbon sources are exhausted, the culture reaches saturation (at ap- proximately to days postinoculation) and the constituent cells cease proliferation and enter the quiescent state. vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ considered a distinct developmental state comes from the gcs � mutant, which proliferates normally in the presence of food, enters quiescence when grown to stationary phase, and maintains viability in quiescence normally but is conditionally defective in exiting from quiescence and returning to active proliferation when nutrients are restored. gcs � mutants are cold sensitive only for exiting from quiescence ( , ). cell quiescence cycle the process of entering into quiescence has traditionally been represented as a reversible reaction, with exit from qui- escence being simply the reverse of entry. however, we think that this view is too simplistic. entry into quiescence is trig- gered when a proliferating cell senses carbon limitation. in contrast, exit is triggered by a different state of the cell (qui- escent) sensing the presence of a carbon source. there is no reason to believe that the processes of entry into and exit from quiescence share any common intermediate states of the cell (see “exiting from quiescence” below). we therefore propose a revision of this traditional view in which entry into, survival in, and exit from the quiescent state can be regarded as a developmental process that, by analogy to the proliferative cell cycle, can be called the cell quiescence cycle (see fig. ). in this view, entry into and exit from quies- cence are distinct processes. as with the proliferative cell di- vision cycle, passage around one complete round of the quies- cence cycle returns the starting cell, to a first approximation, back to its starting state. in reality, each turn of either cycle changes the state of the starting cell: in the case of the cell cycle, the mother cell becomes one generation older (i.e., has reduced replicative capacity); in the case of the quiescence cycle, the cell also becomes older, again with respect to loss of replicative capacity ( ). the cell cycle results in a doubling of cell the number, whereas the quiescence cycle does not. the cell division cycle and the cell quiescence cycle intersect at the g phase (fig. ). in this phase, a cell can enter either the cell division cycle or the quiescence cycle ( , ). in the presence of ample food supplies (and other conditions permit- ting), a g cell passes start ( ) and enters the proliferative cell cycle. the subsequent removal of nutrients does not gen- erally hamper completion of the ongoing cell cycle, which is driven by internally controlled fluctuations in cyclin-dependent protein kinase activity ( ). in the absence of a sufficient carbon source, a g cell fails to pass start and enters the quiescence cycle. unlike the proliferative cell cycle, the quies- cence cycle does not turn under its own steam but cycles with changes in the environment: the lack of nutrients triggers entry into quiescence; the resupply of nutrients triggers exit. mutants defective in the cell quiescence cycle the isolation of mutants defective in key transitions of the cell quiescence cycle is worthy of some consideration. to date, the most frequently reported class of relevant mutants appears to lose viability when cultured to stationary phase: the mutant cells lose the ability to form colonies when subsequently trans- ferred back to nutrient-rich media. in many cases, this inter- pretation may be naı́ve. three subclasses of “stationary-phase” mutants are likely to exist, all of which may be defective in one or more transition of the cell quiescence cycle. the first subclass includes entry mutants, i.e., those that fail to enter quiescence properly. such mutants would be expected to die when starved, given the likelihood that successful entry into quiescence is required for cells to remain viable when starved. the second subclass includes maintenance mutants, i.e., those that successfully enter quiescence (acquire all the key characteristics of quiescent cells) but are unable to main- tain viability in that state. two subclasses of these maintenance mutants are likely to exist: those inherently required for via- bility in the quiescent state itself, and those specifically defec- tive in surviving when starved. the third subclass includes exit mutants, i.e., those that enter quiescence and remain viable normally but are specifically unable to return to the prolifer- ating state when nutrients again become available. the cells of such mutants are viable when starved but are unable to gen- erate cfu on replating. in only a handful of cases have the above distinctions been entertained. thus, mutants reported to be lose viability in fig. . the cell quiescence cycle and its relationship to the cell division cycle. the cell quiescence cycle is the process by which nutri- ent limitation (e.g., carbon starvation in our reference case) causes exit from active proliferation (the cell division cycle) and triggers entry into the stable nonproliferating state, quiescence/g( ). only after a favor- able change in nutrient availability will a turn of the quiescence cycle be completed, since nutrient availability triggers exit from quiescence/ g( ). the cell quiescence cycle and the cell division cycle intersect at the g phase, where a cell has not yet committed to the cell division cycle. in the presence of sufficient nutrients and with no other influ- ences, a g cell will pass start, after which it is committed to completing a turn of the cell division cycle with production of a daugh- ter cell. slow depletion of an essential nutrient such as carbon will allow the completion of an ongoing cell division cycle but will not allow passage through start. in this case of insufficient nutrient availabil- ity, the cell will enter the cell quiescence cycle. gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ stationary-phase cultures may in reality fall into any one of the above classes when properly analyzed. much of the published literature on “stationary-phase”/quiescent mutants should thus be approached with some caution. a second limitation of the published literature is that many investigators have assumed, incorrectly, that any post-diauxic shift culture is in stationary phase, with its constituent cells in quiescence (see above). subclassification of “stationary-phase” mutants is possible. first, many characteristics of quiescent cells are known, and, together, these constitute a reference set of parameters that can be used to determine (or at least estimate) if mutant cells cultured to stationary phase enter quiescence successfully. sec- ond, cell viability can be assayed independently of the ability to subsequently proliferate when refed. it has recently been shown that viability dyes such as methylene blue can be useful to directly determine the viability of starved cells ( ). fur- thermore, as outlined above, viable quiescent cells can mount transcriptional responses to a variety of environmental stresses and chemical treatments. it should be borne in mind that a mutant defective in pro- ducing a protein may show a terminal defect at a stage of the quiescence cycle distinct from the point at which the protein acts in wild-type cells. for example, it is conceivable that a primary defect in fully entering quiescence may not compro- mise cell viability but, rather, may prevent successful exit after the stimulation brought about by addition of nutrients. quies- cent yeast cells are poised to respond to nutrients, should they become available, and can do so within seconds of nutrient resupply. it is likely that a critical property of quiescence is the ability to exit from that state as quickly as possible once con- ditions improve. entry into quiescence significant progress toward understanding the mechanisms regulating entry into quiescence has been made in the last decade. the relevant gene products have been found in a variety ways: by studying the response of yeast to the immu- nosuppressant rapamycin; by identifying temperature-sensitive mutants that arrest in a quiescence-like state at nonpermissive temperatures even in the presence of nutrients, e.g., cdc ( ); and by studying a subset of mutants fortuitously found to selectively lose viability when cultured to stationary phase. here, we discuss the signaling pathways thought to regulate entry into quiescence: the tor and protein kinase a (pka) pathways, apparent negative regulators of the transition into quiescence; and the protein kinase c (pkc) and snf p path- ways, apparent positive activators of the transition (fig. ). our understanding of the signaling networks regulating this transition is still fragmented, and other key regulators doubt- less remain to be discovered. we therefore cannot yet tell the whole story; instead, we summarize a work in progress. tor pathway the immunosuppressant drug rapamycin inhibits prolifera- tion of both yeast and mammalian cells. rapamycin-treated yeast cells appear to enter a quiescence-like state ( ). treated haploids arrest as small, unbudded cells with ’n dna content and undergo many of the gene expression changes character- istic of quiescent cells including repression of the ribosomal protein genes and induction of ubi and hsp ( ). rapa- mycin-treated yeast also synthesize proteins at to % of the level of logarithmically growing cultures, display reduced ac- tivity of rna polymerase i (poli) and poliii and high levels of autophagy ( ), and accumulate the storage carbohydrates glycogen and trehalose. the cytosolic target of rapamycin is fkbp , an immu- nophilin ( ). this binary rapamycin-fkbp complex binds to and inhibits the partially redundant proteins tor p and tor p when complexed with two other essential proteins, lst p and kog p, in the so-called torc complex ( ). the tor proteins (for “target of rapamycin”) are phosphatidyl- inositol kinase-related protein kinases ( ). loss of both tor p and tor p largely phenocopies rapamycin treatment ( ). based on these and other observations, hall and coworkers have proposed that the tor proteins function to repress a quiescence program when nutrients are abundant. they envis- age that nitrogen or carbon starvation would lead to inactiva- tion of the tor pathway, liberation of the quiescence pro- gram, and consequent entry into quiescence ( , , , , , ). some progress has been made in recent years in identifying the downstream functions of tor proteins, although direct in vivo targets of the kinases are still not known. one important downstream component is tap p, which binds to and regu- lates the catalytic subunits of pp a protein phosphatases such as sit p, pph p, and pph p ( , ). the tors promote association of tap p with pp a catalytic subunits when nu- trients are plentiful. both rapamycin treatment and transit through the diauxic shift cause dissociation of tap p from its phosphatase partners ( , , ). thus, the diauxic shift and rapamycin act to downregulate tor function. using microarray profiling, a global picture of the gene ex- pression changes caused by rapamycin treatment (and thus, by implication, inhibition of the common function of tor p and tor p) has emerged (see, e.g., reference ). inhibition of fig. . summary of the known signaling pathways thought to con- trol aspects of entry into quiescence. the tor and pka pathways are active in the presence of nutrients and act to repress aspects of quies- cence. when cells are starved of carbon, both pathways are downregu- lated. inactivation of the tors causes activation (albeit transiently) of pkc, leading to some characteristics of quiescence such as a remod- eled cell wall. the snf pathway is inhibited by the presence of fer- mentable carbon sources such as glucose. when such sources are depleted, snf is activated and contributes to the switch from fermen- tative to respiratory metabolism that is essential for entry into quies- cence. vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ tor function causes activation of gln p and gat p transcrip- tion factors via tap p, resulting in induced expression of nitrogen discrimination pathway (ndp) and carbon discrimi- nation pathway (cdp) genes, which are normally induced by a shift from good to poor nitrogen or carbon nutrient sources, respectively ( ). inhibition of tor function also causes acti- vation of mks p and consequent induction of rtg p- and rtg p-regulated genes, particularly those encoding some of the krebs cycle enzymes ( ), and activation of hap / / / p with consequent induction of genes encoding other krebs cycle enzymes. inactivation of the tors also causes gene expression changes independently of tap p, such as decreased expres- sion of the ribosomal protein genes and coordinated genes encoding components of the translational apparatus ( ) and activation of the transcription factors msn p and msn p, by promoting their dissociation from - - protein anchors in the cytoplasm. these redundant transcription factors drive the ex- pression of the stress response element-containing genes, which are also induced by multiple other environmental stress such as heat shocks and hyperosmotic shocks ( , ). is inhibition of the tor pathway important for the forma- tion of quiescent cells triggered by starvation? probably. the phenotype of rapamycin-treated cells and the inactivation of the pathway on carbon starvation suggests that inhibition of the tor pathway is important, if not critical, for entry into quiescence. in addition, mutants defective in a number of downstream targets of the tors, e.g., in autophagy or in the protein kinase c pathway (see below), die on starvation, sup- porting a key role for the tors ( , , ). unfortunately, no constitutively activated alleles of tor and tor exist, precluding a definitive test of this hypothesis. inactivation of the tors may not be sufficient for the for- mation of truly quiescent cells since rapamycin-treated cells do not appear identical to quiescent cells. first, rapamycin inhibits translation by only to % (i.e., up to half) of the rate measured for untreated, logarithmically growing cultures whereas quiescent cells display . % (i.e., / ) of that trans- lation rate ( , , ). second, rapamycin-treated cells appear to continue to accumulate mass and volume, unlike truly qui- escent cells ( ). finally, rapamycin treatment induces both ndp and cdp gene expression but carbon limitation induces only cdp ( ). whatever the importance of the tors in defining the qui- escent state, it is clear that an understanding of their regulation should inform any model of the elusive nutrient detection systems that regulate the entry into quiescence. the tors are inactivated to some extent at the diauxic shift, by transfer from good- to poor-quality carbon or nitrogen sources or by starva- tion for carbon or nitrogen. the tors are thus responding to the absence of high-quality nutrient sources as opposed to the presence of low-quality ones. many potential regulators of mtor (mammalian tor) have been proposed, including the possibility that it is a direct sensor of cytoplasmic atp by virtue of an unusually high km for atp ( ). how mtor is regulated by nutrients and by growth factors is still hotly disputed at the time of writing, and the identity of the mechanisms that regu- late the yeast tors is also unknown. protein kinase c pathway the yeast pkc, encoded by pkc , responds to cell surface stresses and changes in the actin cytoskeleton during vegetative proliferation ( , , ). pkc p in part regulates a mitogen- activated protein (map) kinase cascade involving the map kinase mpk p ( , , , ). mutants lacking bck , encod- ing the map kinase kinase kinase that acts in this cascade, were reported to die rapidly on nitrogen limitation ( , ). based on this observation, it was proposed that the pkc p- map kinase pathway may be a nutrient sensor. it was recently reported that the pkc p-map kinase path- way is required for viability on carbon or nitrogen starvation or growth of a culture to stationary phase ( ). however, the pathway is unlikely to be a nutrient sensor. rather, it acts downstream of and is transiently activated by tor inactivation ( ). mpk p is also activated transiently at the diauxic shift (i.e., concomitant with tor inactivation) and mpk � mutants begin to lose viability at the same point ( ). activation of the pkc p pathway by tor inhibition occurs by a novel mecha- nism independent of the hcs p and mid p sensors required for detecting cell surface stresses during vegetative prolifera- tion ( , , , , ). the pkc p pathway acts, in part, to promote the acquisition of one key characteristic of quiescent cells on starvation: a reinforced and remodeled cell surface wall ( ). first, mutants defective in the pkc p pathway lyse when starved, and this lysis is coincident with cell death. second, starvation or rapamycin treatment rapidly causes increased resistance to the cell wall- digesting enzyme zymolyase, and this acquisition of zymolyase resistance is dependent on pkc p. this failure of pkc p path- way mutants to acquire resistance to zymolyase occurs before cell death, indicating that the pathway is a bona fide positive regulator of entry into quiescence, which probably acts down- stream of tor inactivation. curiously, rapamycin treatment alone, even in rich media, is sufficient to kill mutants defective in the pkc p pathway ( ). thus, mutants lacking components of the pkc pathway die under all the conditions tested that drive cells into quiescent or quiescence-like states and that inhibit the tors. we infer that the pkc p pathway is inherently required for the formation of viable quiescent cells and not simply for the formation of quiescent cells that can survive starvation. protein kinase a pathway the cyclic amp (camp)-dependent protein kinase (pka) pathway is conserved in all eukaryotic cells and, although the structure of the pathway is not identical in all cells, this path- way is invariably involved in regulating cell growth and devel- opment ( , ). when camp concentrations are low, pka is inactive and exists as a tetramer composed of two catalytic subunits and two regulatory subunits ( , ). there are three forms of the catalytic subunit encoded by the three partially redundant genes, tpk , tpk , and tpk ( ). the regula- tory subunit is encoded by bcy ( , ). when camp con- centrations are high, the nucleotide binds to the inhibitory bcy p subunits, causing dissociation from and activation of the catalytic subunits ( ). tpk p, tpk p, and tpk p appear to have different functions. for example, cells lacking tpk p gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ grow better than wild-type cells on nonfermentable carbon sources, while tpk p is actually required for growth on non- fermentable carbon sources ( ), possibly because these cells arrest prematurely on such nonfermentable carbon sources. the pka pathway acts, in general, as an inhibitor of entry into quiescence. mutants lacking adenylate cyclase activity are unable to proliferate and arrest in a state superficially similar to quiescence ( , , , ). constitutive activation of pka, e.g., by deletion of bcy , causes cell death at the diauxic shift ( , , ), indicating that proper downregulation of the pka pathway is necessary for successful transit to the post- diauxic phase ( , , ). altered bcy p protein, in which the serine residue had been changed to alanine, has a -fold-higher affinity than does the wild-type protein for the catalytic subunits. cultures of cells carrying this allele transit the diauxic shift and enter stationary phase at a lower cell density than do wild-type cells ( ). in addition, cells harbor- ing different alleles of bcy with mutations in the c terminus die at different times during the post-diauxic and stationary phases when cultured to saturation ( ). localization of bcy p and the holoenzyme is dynamic during entry into qui- escence ( ), switching from nuclear localization in exponen- tially growing cells to cytoplasmic localization as the cells ap- proach and enter the quiescent state. if inactivation of the pka pathway is critical for entry into quiescence, then activation of the pathway should be important for successful exit from quiescence when nutrients are again available. this seems to be the case. quiescent mutant cells containing low constitutive activity of the pka pathway (i.e., harboring tpk-wimpy alleles) display a long delay in reentering the cell cycle on addition of glucose-based rich medium ( ). how does nutrient availability regulate the pka pathway? the immediate upstream regulators of camp synthesis are known. the partially redundant g proteins ras and ras are activated by signals from the environment, e.g., nutrient avail- ability. cdc p, an exchange factor ( ), activates ras p and ras p by promoting the replacement of bound gdp to gtp. the activated (i.e., gtp-bound) forms of these small g pro- teins directly bind to and activate adenylate cyclase (cdc / cyr p) ( ), leading to an increase in the level of intracellular camp (for a review, see reference ). one g-protein-coupled receptor system (gpr p-gpa p) ap- pears to act upstream of pka as a sensor of external glucose ( ) and is important for glucose activation of camp synthesis ( ). however, mutants lacking gpr p or gpa p are viable and proliferate normally in glucose-containing media, indicat- ing that this sensing system plays a minor or specialized role in the regulation of the pka pathway. the key regulators of the pathway during entry into quiescence remain elusive. although many observations point to glucose and other carbon sources as being sensed by the pathway, it has recently been reported that starvation for nutrients other than carbon can also result in decreased pka activity ( ). what are the downstream targets of the pka pathway? the pathway inhibits the transcription factors msn p and msn p, which are also targets of the tor pathway (see above) ( , ). rim p, a protein kinase previously shown to stimulate meiotic gene expression, acts downstream of and is negatively regulated by pka ( ). additionally, gis p, a putative zinc finger protein, acts downstream of rim p and mediates tran- scriptional activation via the post-diauxic shift element found upstream of many genes whose expression increases at the diauxic shift ( ). it has recently been suggested that the pka pathway also regulates the ccr p-not complex, which appears to regulate gene expression both positively and negatively via the general transcription factor tfiid ( ). this ccr p-not complex may mediate the repression of msn p and msn p by the pka pathway. the pka pathway may also alter chromatin structure ( ). finally, the pka pathway has recently been shown to be a direct activator of pyruvate kinase (cdc p) ( ) and cox p ( ) in proliferating cells, suggesting a pos- sible role for the pathway in regulating carbohydrate metabo- lism and mitochondrial function at the diauxic shift. the spe- cific role for pka in the post-diauxic and quiescent phases is not known, although it may in part regulate the rye proteins, several of which are ssn/srb subunits of polii and are required for survival in stationary phase (reviewed in reference ). the msn p and msn p transcription factors are negatively regulated by both the tor and pka pathways and are acti- vated at the diauxic shift. curiously, in strains lacking both msn p and msn p, pka activity is dispensable for vegetative proliferation ( ). thus, inactivation of the ras-camp path- way in rich media leads to arrest in a quiescence-like state, in part because of activation of msn p and msn p. importantly, loss of msn p and msn p function also confers modest resis- tance to rapamycin ( ). thus, msn p and msn p are necessary, at least in part, for arrest in a quiescence-like state triggered by pka or tor inactivation in the presence of nutrients. how- ever, activation of msn p and msn p is not necessary for successful entry into quiescence triggered by growth of cultures to stationary phase: msn msn double mutants have been reported to maintain viability for protracted periods, although not as long as do wild-type cells, when starved ( ). snf p pathway the snf gene encodes the yeast homologue of amp-acti- vated protein kinase (ampk) ( ). ampk is activated by a variety of stresses to mammalian cells that change the atp/ amp ratio, and the activation occurs by direct allosteric changes ( ). yeast snf p is also activated when the in vivo atp/amp ratio drops, but the activation is thought to be indirect since the purified kinase is refractive to these nucleo- tides ( ). in the presence of glucose, snf p is inactive, re- sulting in the preferential use of glucose as the carbon source ( , ). when glucose levels drop, snf p is rapidly activated (within mins) and derepresses the expression of genes re- quired for the use of alternative carbon sources and metabolic pathways that generate atp ( ). mutants lacking snf cannot utilize alternative carbon sources such as ethanol and glycerol ( ), and they die when the cultures are grown to high density (actually soon after the diauxic shift). this and other evidence (see below) suggests that adaptation to the use of poor carbon sources and the ability to respire are necessary for proper entry into a stable quiescent state. an emerging signaling network there is accumulating evidence that snf p function con- verges with both the pka and tor pathways (and thereby the vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ pkc pathway) in modulating various outputs, including gln p and msn p/msn p (see above) ( , ). snf p activation also induces peroxisomal genes, such as pot ( ), which is neg- atively controlled by pka ( ). in addition to the above inter- actions with snf p, the pka and pkc p pathways appear to intersect based on studies of rpi p, an upstream antagonist of ras that also regulates cell wall integrity ( ) and the wsc genes ( ). interactions between the pka and tor pathways are also known to exist through their effects on msn p and msn p ( , ). thus, the signaling pathways thought to reg- ulate entry into quiescence appear to form an interacting net- work that acts at the diauxic shift in response to the change in carbon quality. the architecture of this putative network is still poorly defined and may be constant through the life cycle of yeast or may itself dynamically change as the cells transit into quiescence. the link between the tor and pka pathways is becoming clearer. mutants lacking both gln p and gat p, known effec- tors of the tip /tap branch of the tor pathway, are only moderately resistant to rapamycin. it has been reported that high- or low-level constitutive activation of the pka pathway confers robust rapamycin resistance on such mutants but not on wild-type cells ( ). further, even in wild-type cells, such misregulation of the pka pathway prevents the acquisition of most, if not all, of the characteristics attributed to regulation of the tip /tap -independent branch of the tor pathway, including repression of the ribosomal protein genes. finally, it has been shown that rapamycin treatment alone causes nuclear localization of bcy , thereby mimicking camp depletion and nitrogen limitation. it thus appears that the ras-camp/pka pathway may act, at least in part, downstream of the tors and in the tip /tap -independent branch. another recent paper ( ) suggests that both pathways control the activity of the rim p protein kinase ( ). rim p regulates the expression of genes containing post- diauxic shift elements in their promoter at or soon after the diauxic shift. importantly, rim � mutants appear to lose via- bility to some extent when cultured to stationary phase (to % cfu in days), fail to acquire some key characteristics of quiescence ( ), and suppress the growth defects of strains lacking the pka pathway activity (as do msn � msn � mu- tants-[see above]). it now appears that the tor and pka pathways have at least one common target, rim p, and regulate multiple com- mon outputs. it is less clear how this regulation takes place. it could be that the pka pathway acts downstream of the tor kinases, as suggested by schmelzle et al. ( ). alternatively, both pathways may act in parallel, as argued by pedruzzi et al. ( ). this issue awaits resolution. working model for the regulation of entry into quiescence although cells acquire many of the characteristics of quies- cence at the diauxic shift, it is clear that in rich, glucose-based medium, entry into quiescence proper occurs when carbon is finally depleted, concomitant with permanent proliferation ar- rest. it thus appears, to a first approximation, that growth of a culture to stationary phase causes at least two distinct changes in cell state: (i) rapid proliferating (fermenting) to slow pro- liferating (respiring), concomitant with the diauxic shift of the culture, and (ii) slow proliferating (respiring) to quiescent, concomitant with saturation of the culture. the first change (at the diauxic shift) reprograms cells for respiration, which may be a necessary precursor for the second change: entry into the nonproliferating quiescent state (see fig. ). each transition in liquid medium is triggered by a distinct environmental change: the first by the lack of a good carbon source, and the second by the lack of any carbon source (fig. ). the recent work by gasch et al. ( ) has supported this two-transition model of entry into quiescence after growth of cultures to stationary phase. one of the experiments in this work involved monitoring the genome-wide gene expression changes (by microarray expression profiling) on growth of a culture for days in rich medium (i.e., to late post-diauxic shift/early quiescence). two results are clear. first, the changes in gene expression that occur at the diauxic shift persist for at least days in culture. second, numerous additional changes in gene expression happen selectively or exclusively after or days, i.e., as the cells approach full quiescence (e.g., induction of the ydr w and snz genes). these late changes in gene expression are not triggered when cells are starved for nitro- gen. these changes may thus be specific for entry into quies- cence proper triggered by carbon starvation. the putative signaling network involving the tor, pka, pkc, and snf p pathways appears to act predominantly at the first transition, concomitant with the diauxic shift (fig. ). other, yet to be implicated, pathways may also act here. we know nothing about the regulators and mediators of the sec- ond step, final entry into quiescence. because mutants harbor- ing different loss-of-function alleles of bcy , the gene encod- ing the inhibitor of pka, appear to lose viability at different points when cultured to saturation, ranging from the diauxic shift (reminiscent of a null mutant) to stationary phase ( ), it is possible that stepwise regulation of some or all of the same signaling network that acts at the diauxic shift also contributes to the final entry into quiescence. maintenance of viability in quiescence the processes of entry into and survival in quiescence are intimately linked. one characteristic of successful entry into quiescence by wild-type cells must be the acquisition of the ability to survive in that state. however, success comes in degrees. a distinction between the processes of entry into and maintenance in quiescence is possible and useful. entry can be viewed as the process by which the key measurable character- istics of quiescence (yet to be defined) are attained (e.g., in- volving signaling pathways and mediators of change of state [see above]); maintenance encompasses the processes by which the characteristics of quiescence acquired on entry contribute to long-term viability of that state. most mutants that lose cell viability when cultured to stationary phase can in practice be subclassified as being entry defective or maintenance defective (see above). in this section, we focus on a few selected pro- cesses that are thought to be important specifically for main- tenance of viability in quiescence. genes required for maintaining viability given the caveat that mutants designated as being required for “survival” in quiescence/stationary phase can be defective gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ in entry into, maintenance in, or exit from quiescence, many such mutants are likely to be required for maintenance of viability in quiescence. an increasing number of such mutants are being identified, and the collection as a whole gives a low-resolution view of the cellular processes that are more critical for the survival of quiescent cells than for the survival of proliferating cells. mutants known prior to have been extensively reviewed already ( ). a deficiency in any of a wide range of cellular functions can cause viability loss in quiescence; these include oxidative stress responses, e.g., sod mutants ( , ); accumulation of polyphosphate in the vacu- ole, e.g., ppn mutants ( ); ubiquitination, e.g., doa mutants ( ); and those lacking specific myristolated proteins, e.g., arf , arf , cdc /prp and las mutants ( ). most recently, genes required for survival in quiescence at °c have been identified among genes coordinately repressed on exiting qui- escence ( ), predominant among which are genes encoding proteins involved in growth regulation, oxidative phosphoryla- tion, and other processes involved in mitochondrial function (m. j. martinez, a. b. archuletta, a. i. rodriguez, a. d. a. aragon, s. roy, c. p. allen, p. d. wentzell, and m. werner- washburne, submitted for publication). “essential” genes that are not required for viability another equally interesting set of genes appear to exist: those that are essential for the proliferative state but are not required for viability in quiescence. one such example is the gene encoding the translation factor eif e ( ). it is thought that translation initiation in quiescent cells does not involve recognition of the mrna cap. thus, some functions are more important to a proliferating cell than they are to a quiescent cell. although other obvious possibilities could easily be pos- tulated, e.g., proteins required for cell division cycle progres- sion should be dispensable during quiescence, we that expect other, more informative cases will be discovered. control of gene expression correct regulation of gene expression is a key process in the cell quiescence cycle. a change in the expression of any given gene can result from altered activity of a particular transcrip- tion factor (see multiple examples elsewhere in this review) but can also be affected by changes in general transcription factors. the latter may also be significant for the cell quiescence cycle. fig. . cell transitions that occur when a culture is grown to saturation cell density. as shown in fig. , as a culture of cells is grown to stationary phase, two distinct and temporally separated transitions occur with concomitant transitions of the constituent cells. at the diauxic shift transition of the culture, cells switch from fermentation to respiration and from rapid proliferation to slow proliferation. the trigger for this transition is thought to be exhaustion of a fermentable carbon source. at this transition, the pka and tor pathways are downregulated and the pkc and snf pathways are activated, the former only transiently. at saturation of the culture, cells switch from a slowly proliferating and respiring state to a quiescent state/g( ) that is also thought to be respiring. the trigger for this transition is thought to be depletion of nonfermentable carbon sources in the medium, i.e., carbon starvation. mediators of this latter transition are not known, nor has a role for the pka, tor, pka, or snf pathways been established. vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ for example, the general transcription factor tfiid comprises the tata box-binding protein and a set of highly conserved associated factors (tafiis). tafii , the core subunit of the yeast tafii complex, is dispensable for normal transcription of most yeast genes but is specifically required for progression through the g /s transition of the cell division cycle. walker et al. have shown that the levels of tafii , several other tafiis, and tata box-binding protein are drastically re- duced in quiescent cells relative to their levels in proliferating cells ( ). another example is the polii subunit rpb p. yeast cells lacking rpb p proliferate normally at moderate temper- atures ( to °c) but not at temperatures outside this range. when subjected to a heat shock, proliferating cells lacking rpb rapidly lose polii transcriptional activity and subse- quently die. when cultured to stationary phase at a permissive temperature (i.e., permissive for proliferating cells), rpb � mu- tants also exhibit a substantial decline in mrna synthesis relative to wild-type cells and die. moreover, in wild-type cells, the portion of polii complexes that contain rrb p increases substantially as the cells enter quiescence ( ). there is evi- dence that polii complexes need to be covalently modified in some way in order to recruit rpb p, and, again, the portion of modified complexes increases as cells enter quiescence, be- coming the predominant form ( ). translation protein synthesis consumes a huge amount of the energy in an exponentially growing yeast cell. rrna transcription rep- resents � % of the total transcription, and ribosomal protein synthesis represents � % of total translation. it is not sur- prising, therefore, that the first coordinated downregulation of genes that seems to occur during the transition into the qui- escent state is the coordinated, global shutdown of the tran- scription of genes coding for the proteins in both subunits of the ribosome. how this coordinated shutdown is accomplished is not known. despite this shutdown of ribosomal protein bio- synthesis, quiescent cells maintain excess translational capacity ( ) and protein synthesis continues, albeit at very reduced rates (some . % of the rate in proliferating cells) ( ). a few proteins have so far been identified that are selectively synthesized after entry into quiescence ( ). one such protein, designated snz p, is induced later than all other known pro- teins, and its relative rate of synthesis increases with time in quiescence. snz expression also increases in response to star- vation for other specific nutrients, such as tryptophan, adenine, or uracil ( ). increased snz p levels may be a hallmark of a general core quiescence program, one that is shared by the responses to different starvation regimens and one that is likely to be highly conserved, as is snz p itself ( ). it transpires that snz p is required for pyridoxine (vitamin b ) biosynthesis ( , ). why, then, is snz p (and presum- ably snz p activity) induced in quiescence? there are two likely possibilities. vitamin b derivatives may be important cofactors for metabolism in quiescent cells, possibly in amino- transferase reactions. alternatively, these vitamins may func- tion as antioxidant compounds, providing a defense against endogenously generated reactive oxygen species, especially sin- glet oxygen (see below). curiously, there is no direct correlation between steady-state mrna accumulation and protein synthesis for another pro- tein, ssa p, that is synthesized perferentially in quiescent cells. it thus appears that the synthesis of at least some important proteins in the quiescent state is regulated by mechanisms other than mere control of steady-state mrna abundance. protein turnover and covalent modification of n termini cells in stationary-phase yeast cultures do not increase in mass with time. since protein synthesis is known to continue in these quiescent cells (albeit at a low rate), the obvious conclu- sion is that protein synthesis and degradation must be tightly coupled in the quiescent state. however, little is known about the regulation of protein turnover in quiescent yeast cells. evidence from mutants clearly implicates ubiquitin-depen- dent protein degradation as a process essential for the main- tenance of viability in quiescent cells. ubi mutants, which lack polyubiquitin (a natural gene fusion of five ubiquitin se- quences), are unable to maintain viability when cultured to stationary phase or after starvation for nitrogen or carbon ( , ). ubc and ubc mutants, which lack the corresponding ubiquitin-conjugating enzymes, also display reduced viability in quiescence ( ). in the doa � mutant, which is defective in the recycling ubiquitin from ubiquitinated substrates, ubiquitin is strongly depleted from cells under certain conditions, most notably as the cultures approach stationary phase ( ). ubiq- uitin depletion precedes a striking loss of cell viability in sat- urated cultures of doa � cells. this loss of viability of doa � cells is rescued by provision of additional intracellular ubiq- uitin. presumably, ubiquitin becomes depleted in the mutant because it is degraded much more rapidly than in wild-type cells. aberrant ubiquitin degradation in the doa � mutant can be partially suppressed by mutation of the proteasome or by inactivation of vacuolar proteolysis or endocytosis. this latter observation connects protein homeostasis to protein traffick- ing. indirect evidence for the importance of specific targets for regulated turnover comes from experiments with mutations that affect n-terminal acetylation. loss of function of either of the two subunits of the n-acetyltransferase encoded by the nat and ard genes causes a failure of yeast to survive carbon starvation ( , ). the proteomes of both wild-type and nat mutant cells in proliferating cultures have been ex- amined ( ). although only a small subset of the , yeast proteins were identified in this analysis, at least proteins appear to be acetylated by nat p under normal proliferative conditions. intriguingly, these modified proteins included yst p and yst p, structural proteins of the ribosome; asc p, a protein known to interact with the translational machinery; ebf p, a gdp-gtp exchange factor for the translational pro- tein ef- ; bmh p and bmh p, proteins known to affect the pka and tor pathways; and tif p, translation initiation fac- tor eif a. others included the ubiquitin-activating enzyme uba p and several peroxisomal proteins. thus, a number of proteins involved in functions already implicated in entry into or maintenance of the quiescent state are targets of n acety- lation. lipidation of the n terminus of some proteins, e.g., by n myristoylation, is also important for the maintenance of via- bility in quiescence. s. cerevisiae contains four known acyl co- gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ enzyme a (acyl-coa) synthetases, faa p to faa p (for “fatty acid activation proteins”). acyl-coa metabolism regulates protein n myristoylation, a reaction catalyzed by the essential enzyme, myristoyl-coa:protein n-myristoyltransferase (nmt p). the combination of a partial-loss-of-function mutation in nmt and a null mutation in faa results in a progressive millionfold reduction in cfu in quiescence that is associated with a deficiency in protein n myristoylation ( ). this apparent viability defect first appears during logarithmic growth of cul- tures, worsens through the post-diauxic phase, and becomes extreme in stationary phase. curiously, nmt p activity is nor- mally present in cells cultured to log and diauxic/post-diauxic phases but is absent from cells at stationary phase. it thus appears that n-myristoylated proteins present in quiescent cells, and the requirement for them, are “inherited” from prior proliferating states. many known and putative n-myristoylated proteins have been identified in yeast ( ). of the genes identified that encode such proteins, removal of any of the following causes a severe loss of cfu in quiescence: arf , arf , sip , van , ptc , ybl w (homology to snf ), yjr w, ykr w, and vps . thus, protein n myristoylation (dur- ing prior proliferating states) and a number of individual tar- gets of this modification appear to be required for viability in quiescence. autophagy for turnover of cellular components, eukaryotic cells are equipped with several other degradation systems, one of which is the process of autophagy. autophagy is a membrane trans- port pathway leading from the cytoplasm to the vacuole in yeast (or to the lysosomes in mammalian cells) for degradation and recycling. in addition to nonspecific bulk cytosol, selective cargoes such as peroxisomes are sorted for autophagic trans- port under specific physiological conditions. in a nutrient-rich growth environment, many of the autophagic components are recruited to execute a specific biosynthetic trafficking process, the cytoplasm-to-vacuole targeting (cvt) pathway, that trans- ports the resident hydrolases aminopeptidase i and �-manno- sidase to the vacuole. recent studies have identified pathway- specific components that are necessary to divert a protein kinase and a lipid kinase complex to regulate the conversion between the cvt pathway and autophagy ( ). during the autophagic process, a single-membrane struc- ture, the so-called isolation membrane, surrounds portions of the cytoplasm and organelles. fusion of the tips of the isolation membrane to each other forms a double-membrane spherical autophagosome with a diameter of about �m. the autopha- gosome then fuses with lysosomes, and the sequestered con- tents, along with the inner membranes, are degraded by lyso- somal hydrolases ( ). in most cells under most conditions, autophagy is usually suppressed to a very low basal level. some conditions, includ- ing starvation (yeast) and hormonal stimulation (mammalian cells), can trigger dramatic enhancement of autophagy. auto- phagy at the basal rate most probably contributes to the turn- over of cellular components at steady state, whereas starvation- induced autophagy is thought to aid in maintaining an amino acid pool for gluconeogenesis and for the synthesis of proteins essential to survival under starvation conditions. autophagy-deficient yeast mutants die rapidly on starvation ( ). autophagy in yeast has traditionally been stimulated in rich medium by starving for nitrogen, and the relationship of this state to the quiescent state attained on starvation for carbon is unclear. however, increased autophagic activity has been observed in wild-type cells in cultures entering stationary phase, and this induction was impaired in a snf strain ( ). snf p is a putative regulator of entry into quiescence (see above) and is required for glucose derepression. glycogen storage is also defective in autophagy mutants: mutants defective for autophagy are able to synthesize glyco- gen when approaching the stationary phase but are unable to maintain their glycogen stores, because subsequent synthesis is impaired and degradation by phosphorylase, gph p, is en- hanced. deletion of gph partially reverses the loss of glyco- gen accumulation in autophagy mutants. loss of the vacuolar glucosidase, sga , also protects glycogen stores but does so only very late in stationary phase, suggesting that gph p and sga p may degrade distinct pools of glycogen ( ). defective glycogen storage in snf cells may be due to both defective synthesis on entry into stationary phase and impaired mainte- nance of glycogen levels caused by the lack of autophagy, suggesting an important role for this process in the ability of cells to survive carbon starvation. autophagy may actually help connect transcription and translation in starved cells. the yeast eif � kinase, gcn (which is required for translation of the transcription factor gcn p), and the transcription factor gcn , which is regulated by gcn , are required for autophagy induced by starvation ( ). this induction process for autophagy is likely to be functionally conserved since the mammalian eif � kinase, pkr, is able to restore starvation-induced autophagy in yeast cells lacking the gcn gene ( ). interestingly, murine embryonic fibroblasts lacking the mammalian eif � kinase or with a nonphosphorylatable mu- tant form of eif � (due to a ser- mutation) are defective in autophagy that can be triggered by herpes simplex virus infec- tion. furthermore, pkr and eif � ser- -dependent autoph- agy is antagonized by the herpes simplex virus neurovirulence protein, icp . . thus, autophagy is a novel evolutionarily conserved function of the eif � kinase pathway that is both required for viral virulence and targeted by viral virulence gene products ( ). many of the known mediators of entry into quiescence can modulate autophagy. as noted above, snf p is required for increased autophagy as cultures are grown to saturation ( ). in addition, inhibition of the tor proteins by rapamycin in rich media is sufficient to induce autophagy, an induction that is prevented by hyperactivation of the pka pathway ( ). thus, tor and pka activities act to repress autophagy in the vegetative state, and inactivation of these same pathways dur- ing entry into quiescence probably derepresses autophagy. the mechanism by which the tor proteins modulate autophagic activity is partly understood. the protein kinase activity of apg p, the autophagy-regulating kinase, is enhanced by star- vation or rapamycin treatment ( ). in addition, apg p, which binds to and activates apg p, is hyperphosphorylated in a tor-dependent manner, reducing its affinity to apg p. vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ apg p-apg p association is required for starvation-induced autophagy but not for the cvt pathway ( , ). ypt , a small gtpase important for vesicular transport, which is a process known to be essential for exit from quiescence (see below), has also been implicated in autophagy via the effects of its gtpase- activating proteins (ypt p-gaps). ypt p-gap deletion strains exhibit various morphological alterations resembling constitutive activation of autophagy ( ). metabolism yeast cells in quiescence have increased amounts of storage carbohydrates (glycogen and trehalose), whose levels decrease slowly with time in quiescence. are these carbohydrates me- tabolized for fuel? probably not. the long-term viability of cells in stationary-phase cultures does not always correlate with trehalose or glycogen accumulation ( ). the primary func- tion of trehalose may be to protect proteins in quiescent cells from denaturation and damage by oxygen radicals ( ). there is no answer at present to the obvious question: what are quiescent cells using as an energy source? the highest energy output per weight of material in cellular metabolism comes from the �-oxidation of fatty acids. it seems likely, therefore, that cells in stationary-phase cultures derive their energy from the slow metabolism of lipids, but no direct evi- dence for this has been published. there is indirect evidence to suggest that lipid metabolism is important in quiescent cells. loss-of-function mutations in opi , the gene coding for the enzyme that catalyzes the final methylation reaction in phosphatidylcholine biosynthesis, cause cells to lose viability when cultured to stationary phase ( ). it is known that as cells enter the quiescent state, triac- ylglycerol synthesis increases ( ), even though total phospho- lipid biosynthesis decreases ( ). these results suggest that oxidation of triacylglycerols may be an energy reserve for qui- escent cells. since �-oxidation of fatty acids occurs in the peroxisomes of eukaryotic cells, it seems reasonable to assume that there is a role for the peroxisome in survival of quiescence, but no such studies on this organelle have been published. our preliminary observations (j. l. collins and g. a. petsko, unpublished data) indicate that peroxisomal fatty acid metabolism is not impor- tant for the maintenance of viability in quiescence. most other fatty acid metabolism occurs in mitochondria. are these or- ganelles important to quiescent cells? little work has been done to answer this question, but there are already good rea- sons to think that mitochondrial oxidative metabolism may be the chief source of energy for quiescent cells. glyoxalate path- way genes are upregulated in cell cultures on entry into sta- tionary phase ( ). more directly, petite mutants and mutants harboring other mitochondrial loss-of-function defects die rap- idly when starved for carbon in rich media (j. l. collins, g. a. petsko and d. ringe, unpublished data; martinez et al., sub- mitted). redox homeostasis unlike proliferative cells, quiescent yeast cells cannot dilute out damage to proteins and dna by rapid synthesis of new macromolecules and cell division. hence, quiescent cells are potentially more vulnerable to internal and external stresses than are proliferating cells. it is reasonable to assume that quiescent cells have active, maybe even specialized, protection mechanisms to counter any accumulating damage. here, we focus on one such stress, oxidative damage. mitochondrial respiration appears to be a major source of energy for quiescent cells. unfortunately, respiration produces large amounts of reactive oxygen species, whose toxic effects must be countered if viability is to be maintained. we think that proper redox homeostasis is of great importance to qui- escent cell viability. multiple findings support this view. for example, the expression of genes encoding antioxidant en- zymes, mn superoxide dismutase (mnsod), cu,zn superoxide dismutase (cu,znsod), and glutathione reductase, is induced when quiescent cells are exposed to menadione, an oxidizing agent ( ). thus, quiescent cells retain a capacity to detect and respond to oxidative damage. it is clear that the response to oxidative stress is important. longo et al. ( ) studied yeast mutants lacking cuznsod and mnsod (sod and sod , respectively) and determined their long-term viability (by measuring cfu) in stationary-phase cultures in minimal medium. such cells would be in a state related to, but not identical to, our reference quiescent state. in well-aerated cultures, the lack of either sod resulted in dramatic loss of viability over the first few weeks in culture. however, the double mutant died more quickly still, i.e., within a few days. reduction of respiration via a second mutation dramatically increased short-term survival. these results strongly suggest that ongoing mitochondrial respiration is itself a major stress to starved yeast cells. aging versus maintenance of viability the measurable, time-dependent loss of cfu in stationary- phase yeast cultures in synthetic media has been proposed as a model for cellular aging, “chronological” ageing ( ). station- ary-phase cultures in rich media are much more resilient to apparent loss of viability than are saturated cultures in syn- thetic media for reasons that are not yet understood. never- theless, the processes in cells grown to saturation in synthetic medium should, in large part, inform us of the evolution of our reference quiescent state, and vice versa. another type of aging in yeast is replicative aging, defined as the loss of potential to undergo subsequent rounds of cell division cycle in rich media. a newly born daughter cell can undergo only a finite number of subsequent cell divisions be- fore becoming senescent: mutants with a longer replicative life span can undergo more rounds of division from birth to senes- cence in the continuous presence of ample food. it is not clear how the two aging processes, chronological and replicative, are related: some mutation appear to have opposite effects on them, lengthening one while shortening the other, whereas other mutants affect one process only. however, there are a few genes whose deletion appears to affect both ageing mech- anisms in the same way, suggesting that there is some com- monality between the two mechanisms. for example, deletion of sch , a gene encoding a protein kinase that is a possible yeast homologue to the human antiapoptotic kinase akt/pkb, dramatically extends the chronological life span of yeast ( ) in a sod -dependent manner ( ). gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ there is also evidence from yeast studies that longevity in eukaryotes may be negatively regulated by the pka pathway, which is implicated in entry into quiescence. mutations that decrease the activity of the ras-cyr p-pka pathway extend the longevity of yeast cells and increase stress resistance by activating transcription factors msn and msn and the mito- chondrial superoxide dismutase sod p. specifically, deletion of ras , one of the two ras genes in yeast, doubles the chrono- logical life span (overexpression of ras also increases the life span, suggesting that the dependence of life span on ras p activity is denoted by a bell-shaped curve); transposon muta- tion of cyr , the adenylate cyclase that is a downstream target of ras p, has a similar effect ( ). we presume that extension of life span, as opposed to its shortening, cannot be due to a failure to enter quiescence proper, so these observations sug- gest a role for the ras-cyr p-pka pathway in maintenance as well as entry and also suggest a possible connection between these stages of the quiescence cycle. it is known that cells lose replicative capacity with time spent in quiescence proper, demonstrating a direct relationship be- tween replicative ageing and evolution of quiescence. it must be noted, however, that the very concept of yeast as a model for aging in other organisms has been questioned ( ). the specific objections raised do not invalidate the relationships between replicative ageing, chronological ageing, and mainte- nance of viability in quiescence in yeast; the study of one should, in part at least, inform the others. exiting from quiescence resuspending quiescent cells in media containing all neces- sary nutrients (including a carbon source) stimulates exit from quiescence and completion of the quiescence cycle. stimulated (refed) quiescent cells lose thermotolerance, become sensitive to cell wall-degrading enzymes, and display increased rates of rna and protein synthesis. internal carbohydrate stores such as glycogen and trehalose are also mobilized. ultimately, stim- ulated cells resume cell growth and begin proliferation, i.e., enter the proliferative cell cycle ( ). sensing nutrients how does a quiescent cell sense the presence of nutrients? it is possible that the cell has the ability to simultaneously sense the presence of all essential nutrients such that it initiates exit from quiescence only in complete medium. alternatively, and more economically, a quiescent cell may be poised to detect only one or a few key nutrients that would indicate, with sufficiently low risk, that the environment has become permis- sive again for active proliferation. quiescent yeast cells appear to be “risk takers” and primar- ily use the presence of an external carbon source as the key indicator of a favorable change in nutritional fortune. cells allowed to enter quiescence in glucose-based rich medium are able to maintain viability for long periods even when subse- quently transferred to distilled water ( , ). nevertheless, the simple addition of a carbon source such as glucose to quiescent cells in water causes the loss of many characteristics of quiescence ( ). this striking finding indicates that the presence of a carbon source alone is sufficient to initiate, at least in part, the process of exiting from quiescence. in contrast, quiescent cells in water are refractile to the addition of a nitrogen source alone, sup- porting the high predictive value placed by these cells on car- bon availability. this predictive gamble can be risky: the addi- tion of glucose to quiescent cells in water ultimately results in cell death, presumably due to the lack of other essential nu- trients. the presence of a carbon source alone appears, there- fore, to irreversibly commit quiescent cells to attempting to exit from quiescence. transcriptional changes an analysis of genome-wide gene expression changes that occur during exit from quiescence has been performed using slide-based microarrays and at -min intervals after stimulation (martinez et al., submitted). a correlation map of this time course revealed that the greatest changes in gene expression occur within the first to min of stimulation by addition of nutrients. for example, at least genes, including snz , are rapidly and coordinately repressed. in addition, the “ribo- somal” gene set encoding ribosomal proteins and related trans- lation factors (and a potential target of the pka and tor pathways [see “entry into quiescence” above]) is coordinately induced within the first min. over the extended time course, expression of approximately one-third of all genes is altered by a factor of or greater. distinct temporal patterns of expres- sion are observed, indicating that exiting from quiescence is an ordered set of sequential events. it has long been thought that stimulated cells exit from quiescence into the g phase of the cell cycle. ultimately this may be the case, and some genes characteristically expressed in g , such as sw , are rapidly induced upon refeeding. how- ever, exiting cells appear to transit through a unique set of states that do not appear to be similar to any other known state of yeast. the expression profiles of exiting cells appear to be distinct from that of cells in the g phase of the cell cycle or cells at any intermediate stage during entry into quiescence (m. j. martinez and m. werner-washburne, unpublished data). this result requires further study to distinguish the phys- iological from the cell cycle responses during the exit process and to ensure that the cells being studied are synchronous. nevertheless, this surprising finding suggests that cells exiting from quiescence take a unique path back to the proliferating state, a path that is not simply the reverse of that taken during entry into quiescence. the rapid transcriptional response of a quiescent cell to the addition of nutrients leads to additional questions. what is the source of nucleoside triphosphates for this synthesis, and where are they stored? it is possible that early transcription utilizes internal stockpiles retained during quiescence. how is a quiescent cell poised to make such an enormous and coor- dinated response? such a rapid response doubtless requires activation or remodeling of signal transduction pathways, chro- matin structure, transcription factors, and rna polymerases. we do not know the answers to these questions. in another study, brejning et al. ( , ) examined global changes in gene expression after resuspending cells that were post-diauxic (but not yet quiescent) in synthetic defined me- dium containing all essential nutrients. they focused on the lag vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ phase, i.e., the time between stimulation by addition of nutri- ent and the actual resumption of rapid cell proliferation. ap- proximately genes were induced, and genes were re- pressed at least fivefold during the lag phase. again, the expression profiles indicate that lag-phase cells display expres- sion patterns that are distinct from those of actively prolifer- ating or post-diauxic cells. proteome changes no systematic analysis of changes in the proteome during exit from quiescence has been reported to date. however, the proteome has been monitored by two-dimensional gel electro- phoresis during the lag phase on resuspension of post-diauxic shift cells in fresh synthetic complete medium ( ). the overall rate of protein synthesis increased dramatically during the lag phase, with a concomitant increase in the number of proteins detectable on a single two-dimensional gel, from approxi- mately in early lag phase to , in late lag phase. the increased abundance of a protein correlated well with an in- creased amount of the corresponding transcript. thus, there is little evidence to date for wholesale posttranslational control of protein abundance during the lag phase. these results may be relevant to the process of exiting from quiescence. exit mutants the study of mutants defective in exiting from quiescence should complement studies of mutants defective in entry. an analogy can be drawn to the response of haploid cells to the presence of mating pheromone. the addition of mating pher- omone to haploid yeast cells causes a change in cell state from the proliferative state to the nonproliferative shmoo. subse- quent removal of pheromone reverses this change in state. mutants lacking activators of the mating-signal transduction pathway, such as components of a map kinase cascade, fail to respond to pheromone treatment, i.e., cannot enter the shmoo state ( ). in contrast, mutants lacking inhibitors of the mat- ing pathway, e.g., protein phosphatases that inactivate the map kinase cascade, are defective in resuming proliferation after pheromone removal, i.e., cannot exit from the shmoo state ( , ). similarly, mutants unable to exit from quies- cence should be defective in genes encoding distinct and op- posing regulators and mediators to those identified from ge- netic analysis of entry. the process of exit from quiescence has received little at- tention from geneticists to date, although, as outlined above, many such mutants may have been inappropriately classified. only one mutant, gcs , has been confirmed to be specifically defective in exiting from the quiescent state ( , , , ). gcs and vesicular traffic mutants lacking the gcs gene are conditionally (at low temperature, e.g., °c) unable to successfully exit from qui- escence on stimulation by fresh nutrients ( , , , , ). because null alleles of gcs display this phenotype, the con- ditionality is due to a conditional requirement for gcs p ac- tivity. the defect is specific for exit from quiescence, since gcs mutants do not display any problems in other phases of the life cycle, although diploid cells lacking gcs p function are im- paired for sporulation ( , , , ) (g. c. johnston and r. a. singer, unpublished data). quiescent gcs mutants are viable (see below) and can successfully return to active cell proliferation at temperatures higher than °c. the special requirement for gcs p during exit from quiescence at low temperatures is imposed relatively early in the process of en- tering into quiescence, since gcs cells become conditionally unable to resume proliferation soon after the diauxic shift ( , , , ). as indicated above, this degree of starvation is also sufficient to cause cells to acquire many of the hallmarks of quiescence (for reviews, see references and ). at °c, the resupply of nutrients to starved gcs cells stim- ulates cell growth (i.e., mass and volume increase), rna and protein synthesis, degradation of storage carbohydrates, and gene expression changes characteristic of exiting cells ( ). indeed, resupply of nutrients causes the appearance of mrna transcripts from the gcs gene itself at a time when other transcripts also become detectable ( ). the kinetics of these responses is similar to that seen for wild-type cells exiting from quiescence under the same conditions. however, gcs mutant cells subsequently fail to reenter the mitotic cell cycle and pass the start checkpoint ( , , ). this behavior suggests that the gcs mutation does not affect the ability of a quiescent cell to sense and initially respond to the presence of nutrients but, rather, impairs some later process required to fully achieve the proliferative state. the role of gcs p in the late quiescence cycle is suggested by the nature of the gcs p protein itself ( ). gcs p is a gtpase- activating protein (gap) that stimulates gtp hydrolysis by the arf small gtp-binding proteins ( ). arf proteins are known to regulate various stages of vesicular transport in proliferating cells (reviewed in references and ), suggesting that the remodeling of intracellular vesicular transport may be critical for the transition from the quiescent to the proliferating state. gcs expression is not restricted to, and is not uniquely affected by, exit from quiescence. thus, gcs p probably plays a role both in the vegetative state and in exiting from the quiescent state. these roles may be the same or distinct. what is the role of gcs p in proliferating cells? the yeast genome encodes several proteins that are related in structure and function to gcs ( , ). one of these, age p, is an- other arfgap whose in vivo function in proliferating cells overlaps that of gcs p: although gcs or age single mutants cells proliferate normally, the gcs age double mutant is invi- able ( , ). this overlapping and essential function of the two proteins in proliferating cells appears to be to enable transport of vesicles from the trans- golgi network ( ). the double mutant lacking both proteins displays a severe impair- ment in endosomal vesicle traffic. what is the role of gcs p during exit from quiescence? gcs mutants undergoing the transition from quiescence back to cell proliferation at a low (restrictive) temperature also display a severe endosomal impairment ( ), similar to that shown by vegetative cells lacking both gcs p and age p ( ). although it has not yet been demonstrated conclusively, this vesicle traf- ficking defect may account for the failure of gcs mutants to successfully exit from quiescence. in support of this possibility, replacing the in vivo wild-type allele of gcs with a mutated version encoding a gap-dead form of the protein ( ) mim- gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ ics the exit defect of gcs null mutants (c. l. adams, s. lewis, r. a. singer, and g. c. johnston, unpublished data). if gcs p performs the same function in cells exiting from quiescence as it does in proliferating cells, why do gcs single mutants display a specific defect in transiting from the quies- cent to the proliferating state at low temperature? there are three likely possibilities. first, a cell exiting from quiescence may require an unusual amount of endosomal trafficking to successfully and physically transform itself into a proliferation- competent state, especially at low temperature. however, re- duction of the overall arfgap activity of a cell by deletion of the age gene alone does not affect its ability to exit from quiescence at any temperature, making this possibility unlikely. second, it may be that age p function (or some component of an age p-mediated pathway) is impaired during exit from quiescence, particularly at low temperatures. in this scenario, a stimulated gcs mutant cell would effectively lack both age p (or age p-related) and gcs p functions at low temperature, only the latter because of mutation. finally, gcs may perform another function that may directly or indirectly affect endoso- mal traffic and that is not shared with age p. such a function could be unique to, or uniquely required for, exit from quies- cence at low temperatures. a possible function has recently come to light. a subset of mammalian arfgap proteins, the centaurins ( ), regulate both vesicle transport and rear- rangements of the actin cytoskeleton at the plasma membrane and endosomal compartments. gcs p appears to be the yeast homologue of centaurin-� ( ). interestingly, gcs mutants dis- play abnormal actin cytoskeletal organization specifically when exiting from quiescence at °c (johnston and singer, unpub- lished). thus, a defect in actin organization may underlie, at least in part, the defect in resumption of cell proliferation from quiescence ( ) exhibited by gcs mutants. conclusions and perspectives quiescence is poorly understood for any organism. even for yeast, progress has been limited. there are many possible reasons for this, as discussed above, including the apparent modest life-style of quiescent cells and misconceptions about their viability. however, additional factors appear to have clouded the field. herein, we focus attention on only one quiescent state of the cell, i.e., that achieved by growth of liquid cultures to satura- tion in rich medium. we currently call this state “quiescence” and limit the use of the term to this case alone. this is an operational definition only. it allows us relate the findings of different researchers who have worked on cells derived by the same operation. in reality, it is likely that yeast cells can enter any one of a series of related and stable quiescence-like states depending on the environmental trigger. for example, nonpro- liferating states can be triggered by starvation for carbon, ni- trogen, or phosphate in rich or synthetic defined media, by sporulation of diploids, and even by transfer of proliferating cells to distilled water. we do not know if the states entered as a result of all these treatments are largely similar (i.e., if there is a core quiescence program) or not. because of this uncer- tainty, data acquired for any one state may or may not be relevant to any of the others. for rapid progress to be possible in the study of quiescent states, it is critical that each state be studied separately. this has not been the case to date. for example, as argued above, cells in cultures that have just arrested at or passed the diauxic shift are not in the same state as cells in saturated cultures, yet the two cell states have often been confused. cells from sta- tionary-phase cultures (i.e., cells starved for carbon) have been studied more intensively than have other nonproliferating cells and as such are the most understandable. however, focusing attention on one state for study does not necessarily help with gleaning information and understanding from cells that do not appear to do much. thankfully, recent advances in experimental methodologies and increasing avail- ability of reagents derived from the exploitation of the genome sequence are coming to the rescue. a first step toward fully understanding the biology of quies- cent cells is to characterize the quiescent state itself and the way in which it differs from the proliferating state. for exam- ple, genome-wide gene expression profiling (see, e.g., refer- ence ) can be and is being done to uncover the differences between the gene expression patterns of quiescent and prolif- erating cells ( , ). furthermore, large-scale analysis of the proteome is increasingly viable, including assays of the protein concentration, localization, covalent modification, and com- plex formation (see, e.g., references and ). thus, in addition to the known measurable phenotypes of quiescent cells, such new technologies will add countless oth- ers. the definition of the quiescent state would allow a com- parison with other nonproliferating states, permitting the re- lationships between all of them to be finally estimated with good confidence. furthermore, knowledge of the unique prop- erties of quiescent cells will contribute to our understanding of the processes by which these cells remain so stubbornly viable. studying the dynamic processes of entry into and exit from quiescence in similar detail should be particularly informative. which signaling pathways regulate each stage during entry and exit? this question is potentially answerable. furthermore, it should not be assumed that maintaining viability in quiescence is not itself dynamic. it is likely that the state of the cell evolves with time in quiescence, as internal energy reserves become depleted and as the cell copes with ongoing environmental assault, e.g., oxidative stress. we know that this dynamic evo- lution of the quiescent state is likely to occur, because a related phenomenon in yeast is well known, i.e., chronological aging (see above). understanding how a cell physically transits back and forth between the proliferating and quiescent states is a more for- midable challenge, since such transitions appear to involve the wholesale remodeling of many (if not most) cell processes and structures. even a partial list of the known and coordinated changes associated with these transitions includes changes in many signal transduction pathways; chromatin structure; tran- scription rate and pattern; mrna stability; translation rate, pattern, and mechanism; protein stability; covalent modifica- tion of protein; vesicular traffic; mitochondrial structure; and cell wall structure. beneath this complexity lies a big reward: understanding the mechanisms by which the many cellular processes that underlie active growth, and that are mostly studied in isolation in proliferating cells, are coordinately reg- ulated. analytical methods alone will be very useful, but the com- vol. , quiescence in yeast o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ bination of genetics and these technologies promises to gen- erate the main revolution in our understanding of quiescence. as outlined above, the subclassification of mutants that lose colony-forming potential after growth to stationary phase means that mutants defective in individual aspects of entry into, maintenance in, and exit from quiescence can be identi- fied. the availability of genome-wide deletion collections and the ability to screen such collections robotically means that large numbers of cell quiescence cycle (cqc) mutants will soon be identified. one of the motivations for studying quiescence in yeast is the hope that it might prove to be a model for the behavior of quiescent mammalian cells ( ). a number of cells in more complex eukaryotes exit the mitotic cell cycle permanently on terminal differentiation. the most important in terms of hu- man health and disease are the neurons ( ). humans are prey to a host of neurodegenerative diseases, both sporadic and inherited. most of these diseases seem to result from the accumulation in neurons of aggregates of misfolded proteins ( ), although the exact mechanism of neurotoxicity is not established. increased oxidative stress has been implicated in the etiology of many of these diseases: for example, oxidatively damaged proteins are present in the aggregates found in neu- rons of patients with alzheimer’s disease and parkinson’s dis- ease ( ), and loss-of-function mutations in dj- , a protein implicated in the response of the cell to oxidative stress, cause early-onset parkinson’s disease ( , , ). in the familial forms of many neurodegenerative diseases, the mutated pro- teins are expressed in many different cell types (dj- , for example, is ubiquitous), yet the predominant phenotype is the death of specific classes of neurons. what makes neurons particularly vulnerable to protein dam- age and/or the loss of proteins that protect against such dam- age? it is tempting to conclude that at least part of the expla- nation is that these are quiescent cells (albeit ones that are highly active in certain specific metabolic processes) and there- fore cannot dilute out or repair the damage as efficiently as proliferating cells can ( ). understanding the factors respon- sible for the survival—and death—of quiescent yeast cells, which have homologues for many of the genes encoding pro- teins such as dj- and sod, associated with human disease, may lead to a better understanding of the vulnerability of neurons to degeneration ( ) and, it is hoped, also give clues to how such degeneration may be prevented. recently, evidence has also emerged that degenerating neu- rons in several different human diseases display markers indi- cating that they have attempted to exit from g( )/quiescence and reenter the cell cycle, including expression of cyclin-de- pendent protein kinases and their regulators ( ). reexpres- sion or deregulation of the genes involved in exit from quies- cence may thus be an important step in neurodegeneration. a better understanding of this stage of the cell quiescence cycle may present new opportunities for therapy ( , , ). in conclusion, we hope that it has become clear that the cell quiescence cycle is as important a process to life on this planet as is the mitotic cell division cycle. by the time of our next review, we hope that the cell quiescence cycle is as active and productive a topic of study as is the cell division cycle today. acknowledgments we thank the members of the gray, werner-washburne, petsko/ ringe, and johnston/singer laboratories for helpful discussions. one of us (g.a.p.) is especially grateful to jeremy thorner, who first brought the phenomenon of stationary-phase survival to his attention and who encouraged his budding interest (pun intended). work in the gray laboratory has been supported by funds from the royal society, the wellcome trust, the ibls research committee, and the biotechnology and biological sciences research council. the petsko and ringe laboratories thank the ellison medical foundation for support. research in the johnston/singer laboratory has been supported by funds from the canadian cancer society through grants from the national cancer institute of canada and grants from the canadian institutes for health research. research in the werner- washburne laboratory has been supported by funds from the national institutes of health. references . ashrafi, k., t. a. farazi, and j. i. gordon. . a role for saccharomyces cerevisiae fatty acid 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as suppressors of the loss of arf function in the yeast saccharomyces cerevisiae. j. biol. chem. : – . . zhu, h., m. bilgin, and m. snyder. . proteomics. annu. rev. biochem. : – . . zhu, x. y., n. demolis, m. jacquet, and t. michaeli. . msi suppresses hyperactive ras via the camp-dependent protein kinase and indepen- dently of chromatin assembly factor- . curr. genet. : – . gray et al. microbiol. mol. biol. rev. o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://m m b r.a sm .o rg / d o w n lo a d e d fro m http://mmbr.asm.org/ asymmetry, symmetry and beauty symmetry , , - ; doi: . /sym symmetry issn - www.mdpi.com/journal/symmetry article asymmetry, symmetry and beauty hector sabelli *, atoor lawandow and abbe r. kopra chicago center for creative development, n. lakeview, chicago, illinois , usa; e-mail: alawandow@uchicago.edu (a.l.) * author to whom correspondence should be addressed; e-mail: hector_sabelli@rush.edu. received: june ; in revised form: july / accepted: july / published: july abstract: asymmetry and symmetry coexist in natural and human processes. the vital role of symmetry in art has been well demonstrated. this article highlights the complementary role of asymmetry. further we show that the interaction of asymmetric action (recursion) and symmetric opposition (sinusoidal waves) are instrumental in generating creative features (relatively low entropy, temporal complexity, novelty (less recurrence in the data than in randomized copies and complex frequency composition). these features define bios, a pattern found in musical compositions and in poetry, except for recurrence instead of novelty. bios is a common pattern in many natural and human processes (quantum processes, the expansion of the universe, gravitational waves, cosmic microwave background radiation, dna, physiological processes, animal and human populations, and economic time series). the reduction in entropy is significant, as it reveals creativity and contradicts the standard claim of unavoidable decay towards disorder. artistic creations capture fundamental features of the world. keywords: poetry; music; bios; chaos; creativity . introduction here we study music and poetry with mathematical methods that analyze symmetry and creativity. the relation between music and mathematics has been recognized since pythagoras. the concept of symmetry has found many applications in science and art, but the term is given several different interpretations. thermodynamics defines the spontaneous increase in entropy as an increase in symmetry, and, according to nineteenth century thermodynamics, natural processes tend to decay. in contrast, physics interprets symmetry as regularity, and esthetics highlights symmetry as a defining open access symmetry , feature of beauty and art. evolutionary theory states that natural processes are creative; human and artistic creativity thus continue natural creativity. the term symmetry originally meant a sense of harmonious, aesthetically pleasing proportionality that embodies beauty. soon the term symmetry acquired a more precise meaning of mathematical balance such as when one shape becomes exactly like another if you flip ("mirror" symmetry), slide, or turn it. in time, symmetry came to be defined when this internal identity could be demonstrated according to the rules of a formal system. a mathematical object is symmetric with respect to a given mathematical operation, if, when applied to the object, this operation preserves some property of the object. the set of operations that preserve a given property of the object form a group. symmetry has been transformed in physics to mean invariance under any kind of transformation. according to noether's theorem, a continuous mathematical symmetry corresponds to a conserved quantity. symmetry has come to mean any form of conservation; conversely, creation is associated with change and asymmetry. there is an ideological implication in interpreting symmetry as conservation. in this sense, it is said that most if not all laws of nature originate in symmetries [ ]. asymmetries such as the golden proportion are described as “symmetries”. this overlooks the fundamental role of asymmetry in physical and esthetic processes. symmetry does not exclude its opposite, asymmetry, but it is paired with it, as all opposites are. indeed, for reasons of symmetry, symmetry itself must be paired with asymmetry. the concept of asymmetry has evolved from the mere lack of symmetry to the asymmetry of time in physics and biology, the discovery of asymmetry in biological molecules by pasteur, and the demonstration of symmetry breaking as a core process in physical and biological evolution, from pierre curie to the nobel prize winners nambu, kobayashi, and maskawa. parity symmetry is violated by phenomena that involve the weak force, and there also are violations of charge symmetry and of cp- symmetry. asymmetry is central in natural and human processes. asymmetry is also central to beauty and art, as illustrated by the golden proportion : . , utilized in classic architecture, renaissance and contemporary painting, books, and postcards. asymmetry and symmetry coexist as fundamental forms among mathematical and psychological structures. bourbaki, a seminal group of mathematicians, described the architecture of mathematics as based on three foundations, lattices, groups and topology [ ]. lattices, groups and topology are mathematical abstractions of order, symmetry, and spatial form. the leading swiss psychologist jean piaget [ ] was astonished to realize that the fundamental cognitive structures he had discovered in the study of mental development corresponded to bourbaki’s three ‘mother structures’ of mathematics. bourbaki’s mother forms—linear asymmetry, two-dimensional and bipolar symmetry, and vertical hierarchy as a sequence of steps—were prefigured in one of the earliest artistic archetypes: the first pyramid constructed by the prime minister and physician imhotep (author of the first medical (and scientific) textbook, identified with asclepius by the greeks and the romans), the ziggurats built by the sumerians, elamites and assyrians, and the step pyramids built by the mayans, mexicans and incas (figure ). symmetry , figure . step pyramid archetype. top: early pyramids in egypt, middle east, and mexico. bottom: diagram illustrating how it captures asymmetry, symmetry of opposites, and transformation from simple and larger to a smaller top. the bourbaki forms also correspond to macroscopic features of the three dimensions of the central nervous system [ ] that is the most complex system known: the asymmetry of sensory to motor function in its dorsal ventral axis, symmetry in its right-left axis, and the creation of complex forms from the folding of simpler ones in the vertical axis. thus sabelli [ - ] proposed that asymmetry, symmetry and continuous topological transformation from simple to complex (evolution) are the three fundamental patterns of processes, and that asymmetry and symmetry represent a primordial opposition that accounts for creativity in nature as well as in art. asymmetry is evident in non-stationary and non-periodic processes, both stochastic (random walks) and causal (bios). together, asymmetry, creativity and nonrandom causation define bios [ ], a fractal pattern generated mathematically by recursions that involve both asymmetry and symmetry (figure ). we first identified bios as a distinct pattern when studying heartbeat series; this led us to develop analytic methods that demonstrate causality and creativity in empirical processes. bios is commonly found in natural and human processes: quantum processes [ ], the expansion of galaxies and quasars in three surveys [ , , ] gravitational waves [ ], cosmic microwave background radiation [ ], dna [ ], physiological processes [ , - ], animal populations [ ] and human populations [ ], economic time series [ - ] and the prime numbers [ ]. levy et al [ ] have already demonstrated bios in several musical scores; we have expanded this work in this and other publications [ ]. in other words, asymmetry is natural, a core property of complex and creative processes. causality and creativity define bios and differentiate it from chaos and from random walks. bios can be generated mathematically by several recursions that combine the temporal asymmetry of action and the symmetry of bipolar feedback [ , ]. the sinusoidal function provides a mathematical model symmetry , for the philosophical tenet advanced by heraclitus, empedocles, lao-tzu, hegel, darwin, and salk that the interaction of opposites creates novel and complex processes [ ]. this connects bios with both creativity and a well-supported hypothesis regarding its generation. to study artistic creations and archetypes in relation to natural processes is meaningful. artistic archetypes portray fundamental patterns of nature, as highlighted by pythagoras who found in music the mathematics of the universe. in this paper we demonstrate asymmetry, symmetry and creativity in music and poetry using mathematical techniques that measure these features in time series. figure . process equation. the sequence of patterns in steps of increasing complexity in the time series generated by the equation as g increases (logarithmic scale). g = . g = . methods the data presented in the figures above are time series and therefore have no physical dimensions. we analyzed the sequence of notes in musical scores and the sequence of letters in literary texts in english and spanish. the data were compared with mathematical models of non-periodic variations: random series, random walks, and stationary chaos and non-stationary bios generated by the process equation [ ] (figure ) for g = . and . we measure the degree of asymmetry these musical and poetic texts and its changes in time by dividing the series into epochs and computing the middle, mean and median of each epoch. to measure symmetry and opposition we use complement plots [ ] (graphs of the sine versus cosine of each term of the series) and trigonometric walks [ ] (cumulative sum of the sine versus cosine of each term of the series). complement plots omit the linearity of time but conserve temporal order (in the symmetry , lines connecting successive points of the series). as sine and cosine are orthogonal to each other, this creates a -d plot. sine and cosine are out of phase; one of these opposites is larger at each time and the data are plotted in a -d helix rather than a -d circle. complement plots thus assume the priority of time, the asymmetry of opposites and the alternation of their relative size. the helix is a classic portrait of dialectic oscillation of opposites we analyze these musical and poetic texts with recurrence methods using the bios data analyzer [ ]. given a series a , a , …, an, we construct the sequences (euclidean vectors) yi of n successive members of a time series [yi = (ai, ai+ , ai+ , ..., at+n)] starting with each data point ai:. this is referred to as embedding in dimension n. recurrence isometries are calculated by comparing the euclidean norms of these vectors, and if the difference between them is less than a chosen cutoff radius ( %), a recurrence is plotted and counted. we have made calculations with many cutoff radii, anging from . to % and the reults are similar. the quantification of recurrences at low and high embeddings allows one to consider both simple and complex patterns. recurrence plots graph isometries as a function of time. recurrences are colored according to their distance from red to violet. both types of recurrence generate the same pattern in recurrence plots, but the number of isometries increases and the number of similarity recurrences decreases with the length of the vector. isometry is the number of isometric recurrences as a percentage of the total number of possible recurrences in the sample (n x n / ). the number of isometries (as % of the total number of possible recurrences) is computed for the original data and for a copy of the data randomized by shuffling. novelty is defined as the increase in recurrence isometry produced by shuffling the data [ , ], and is quantified as the ratio of isometries after shuffling over isometries in the original data. novelty is a key measure to distinguish creative from non-creative processes. novelty is demonstrable for recurrence isometry but not for similarity recurrence. embedding plots present the value of novelty computed with , , …, embeddings. in addition to analyzing the time series, we also analyzed the time series of difference between consecutive terms. periodic series as well as causally generated non-periodic series (chaos, bios) show morphological and numerically quantifiable pattern in the series of differences, while random series and random walks do not show pattern (randomness) in the series of differences between consecutive terms (except at very high embeddings). the standard deviation s.d. = √(∑ (xi-mean) /n) of the series was recorded as a function of time. series converging to an attractor display a decrease in s.d. with increasingly larger samples. in contrast, diversification is the increase in variance of a time series with an increase of the size of the sample (global diversification) or with increasing the embedding (local diversification): the sd is computed for sets (“embeddings”) of , , …, consecutive terms of the time series, starting with each term in the series. the values obtained for each embedding are averaged for the entire series, and these averages are plotted as a function of the number of embeddings. the power spectrum of these series was calculated using a program developed by patel (patel and sabelli, ). we measured entropy h with the de moivre equation adopted by boltzmann, and by shannon to measure entropy, using a range of bins (n = , , , …), and plot the value of entropy as a function of the logarithm of the number of bins (figure ). the values for entropy h a linear function of the logarithm of the number of bins: symmetry , h = s + d* log n where n is the number of bins used to calculate entropy [ ]. the slope d (for diversity) of the entropy- bin regression line measures diversity of the data (figure ); the slope is for numerical series with two equally probable values, regardless of their temporal arrangement (random or periodic), and increases with the number of different values in the data from period to period , ,…, and chaos. linearly increasing series, random series, statistical noise (random walks, pink noise), chaotic series, biotic series, and many empirical time series have a near slope. the intercept s (for symmetry s) of the entropy-bin regression line at bins (the least number of bins required for the calculation of entropy) is for all symmetric distributions (random, sinusoidal, chaotic); asymmetry y (s < )is present in mathematically generated biotic series, in random walks and in empirical data (physical, biological, economic). figure . entropy-bin plot. plot of informational entropy as defined by shannon. it shows the calculation of the degree of symmetry (entropy at bins = for perfect symmetry and less than for asymmetry) and diversity (slope). many natural and human processes are highly asymmetric. biotic series and random walks have a small degree of asymmetry, while chaos, random, and periodic series are symmetric. . results . . asymmetry and symmetry histograms (figure ) and pareto histograms (figure ) demonstrate asymmetry in the distribution of notes and letters in musical and literary texts. statistical measures quantify asymmetry and demonstrate non-stationarity (figure and table ). symmetry , figure : histogram showing asymmetry in the statistical distribution of letters in poetry (hugo’s a sunset and wordsworth’s lines written as a school exercise at hawkshead) and musical notes (georges bizet’s “habanera” from carmen and bach’s prelude). units: the number of occurences are plotted in the y-axis. hugo: a sunset wordsworth: line s habanera: randomized symmetry , figure . pareto histogram and logarithmic trendline (except for random walk, where a linear trendline fits). mathematical series artistic series random and logarithmic trendline josé hernández, martin fierro “aqui me pongo a cantar…” and logarithmic trendline random walk and linear trendline bach, fantasia and logarithmic trendline chaos process equation g = . and logarithmic trendline bach prelude and logarithmic trendline bios process equation g = . and logarithmic trendline mozart sonata no. , k. , and logarithmic trendline symmetry , figure . quantification of asymmetry in music and poetry. process equation chaos bios poetry c. baudelaire, une charogne v. hugo, a sunset symmetry , figure . cont. e. brontë, a day dream music l. von beethoven, sonata j. s. bach, fantasia s. joplin, the entertainer symmetry , table . asymmetry of opposites. series max min middle mean median mean - median middle - median middle– mean cosine/sine average random . . . . . - . . . . random walk . - . . . . . . . . chaos . . . . . . - . - . . bios - . . - . - . - . . . - . prime numbers . . . - . music bach: prelude . . . - . - . . bach: fantasia . - . - - . . freeman: affair in san miguel . . - . - . - . . duke: april in paris . . . - . - . . poetry whitman: a sight in camp . . - . - . - . . rumi: descent . - . - - . . neruda: puedo escribir . - . - - . . fierro: aquí me pongo a cantar . . - . . . . zorrilla: don juan tenorio . . - . - . . . two dimensional plots (figure ) do not show simple patterns as in chaos or bios. trigonometric plots (figure ) show rounded complement plots (not partial as in chaotic attractors), significant asymmetry. table presents statistical and trigonometric measures of the asymmetry of opposites. symmetry , figure . time series a(t), and twodimensional plot of a(t) vs. a(t+ ). mathematical series artistic series random josé hernández, martin fierro “aqui me pongo a cantar…” random walk j.s. bach, fantasia chaos process equation g = . j. s bach, prelude bios process equation g = . w. a. mozart, sonata no. , k. figure . complement plots (left) and trigonometric walks (right) of musical compositions and of poems. b ac h , p re lu d e b ac h , f a n ta si a symmetry , figure . cont. f re em an , a ff a ir i n s a n m ig u el d u k e, a p ri l in p a ri s w h it m an , a s ig h t in c a m p r u m i, d es ce n t symmetry , figure . cont. n er u d a, “ p u ed o e sc ri b ir l o s ve rs o s m á s tr is te s es ta n o ch e… ” f ie rr o , a q u í m e p o n g o a c a n ta r z o rr il la , d o n j u a n t en o ri o . . entropy table shows that maximal entropy occurs for ordered series such as a sequence of linearly increasing numbers, not for random data, as often assumed. musical and literary texts have relatively low entropy. figure shows that this low entropy results from low symmetry rather than from decreased diversity. both of these results are also observed in biotic series generated mathematically as well as in natural processes. symmetry , table . low entropy of music and literary compositions. series entropy at bins music debussy, Études . di capua, o sole mio . beethoven, für elise . chopin, ballade no. in f . denver, country roads . bach, fantasia . poetry hugo, a sunset . pushkin, eugene onegin book i & ii . goethe, to luna . mandelstam, tristia . blake, on another’s sorrow . whitman, a sight in camp . mathematical series random . random walk . linearly increasing numbers leap (process equation, g = *п) sine wave . devil staircase . lorenz chaos . rossler chaos . process equation chaos at+ = at + . * sin(at) . bios: process equation at+ = at + . * sin(at) . bios: sum of sine waves . bios: sum of sine waves . natural and social processes distance between galaxies . schrödinger’s equation . el niño . air temperatures . clear water river . earthquakes . msn temperature . heartbeat intervals . electroencephalogram . human dna . human rnd . france population . daily bond yield daaa . symmetry , figure . entropy of musical compositions and of literary texts as a function of the number of bins. the musical compositions analyzed include: eduardo di capua’s o sole mio, georges bizet’s habanera from carmen, bach’s crab canon, mozart’s fur elise, the american spiritual swing low sweet chariot, and chopin’s ballade no. . the poems are: wordsworth’s lines written as a school exercise at hawkshead, pushkin’s eugene onegin, ginsberg’s howl, hugo’s a sunset, mandelstam’s tristia, and goethe’s to luna. entropy in music entropy in poetry symmetry , figure . cont. . . power spectrum analysis the power spectrum analysis of poems and music (table ) shows a broad spectrum. the slope of musical compositions is low, in the range of chaos, well below - (pink noise) and - . (bios generated with the process equation). there is great diversity in the slope of poems. table . power spectrum analysis. model time series slope + standard error model time series slope random random walk process chaos . logistic chaos - . bios - . sum of sine waves - . + . pink noise - . brownian noise - . physical processes slope + standard error human processes slope + standard error quantum - . + . heartbeat intervals - . + . gravitational waves - . + . economic - . + . music slope + standard error poetry slope + standard error piano sonata - . + . ginsberg: howl . + . april in paris - . + . wordsworth - . + . fantasia - . + . hugo . + . chopin ballad - . + . mandelstam: tristia . + . . . biotic patterns in music and poetry isometry quantification (figure ) demonstrates less recurrence (novelty) in many musical pieces, bios, and random walks than in randomized copies, and more recurrences in many literary texts and in stationary chaos than in randomized copies. symmetry , figure . quantification of isometry as a function of the number of embeddings in musical compositions and literary texts as compared with their randomized copy (blue line). poetry hugo: a sunset pushkin: eugene onegin book i and ii goethe: to luna mandelstam: tristia music chopin, polonaise beethoven, für elise georges bizet, habanera (from carmen) eduardo di capua, o sole mio symmetry , figure . cont. american spiritual: swing low sweet chariot bach, prelude mozart, piano sonata no. bach, fantasia recurrence portraits of musical and literary (figure ) series show changes in pattern with time (temporal complexity), as observed in mathematical bios and in random walks; in contrast, the recurrence plots of stationary random series or chaotic attractors are uniform. figure . recurrence plots of musical compositions show temporal complexity. the quantification of isometries shows novelty and the quantification of consecutive isometries supports non-random causation. isometry ( embeddings) isometry ( embeddings) embedding plot of isometry embedding plot of consecutive isometry mathematical series random symmetry , figure . cont. random walk chaos bios music swing low sweet chariot habanera from carmen symmetry , figure . cont. di capua, o sole mio bach: crab canon poetry wordsworth: lines written as a school exercise at hawkshead pushkin: eugene onegin hugo: a sunset symmetry , figure . cont. ginsberg: howl recurrence plots and quantification of the series of differences between consecutive terms (figure ) in these data also show temporal pattern in music, chaos and bios, indicating nonrandom causation, in contrast to random walks. figure . series of differences between consecutive terms pattern in the recurrence plots and the quantification of isometry and of consecutive isometries in the show non-random causation. recurrence plot of isometry ( embeddings) recurrence plot of isometry ( embeddings) embedding plot of isometry embedding plot of consecutive isometry mathematical series random random walk symmetry , figure . cont. chaos bios music swing low sweet chariot habanera from carmen o sole mio symmetry , figure . cont. bach: crab canon poetry wordsworth: lines written as a school exercise at hawkshead pushkin: eugene onegin hugo: a sunset ginsberg: howl symmetry , figure shows temporal variation in variance, with overall increase in s.d. with embedding (local diversification) but not with time (global diversification). figure . diversification. s.d. variation by epochs, global and local diversification. music s.d. by epochs global diversification local diversification crab cannon fantasia april in paris poetry cummings: anyone lived in a pretty how town symmetry , figure . cont. whitman: a sight in camp hernandez: martin fierro first strophe neruda: puedo escribir los versos más tristes esta noche zorrilla: tenorio rumi: descent symmetry , figure . cont. rumi: gone to the unseen hugo: a sunset goethe: to luna . discussion these results indicate that asymmetry, symmetry and creativity are evident in literary and musical series. asymmetry is indicated by histograms (figure ), pareto histograms (figure ) and the difference between middle, median and mean (figure ). symmetry is indicated by complement plots (figure ). poems and musical scores show low entropy; low entropy indicates order and creativity just as high entropy indicates disorder and decay. simple mathematical analyses of literary and musical series also reveal local diversification, temporal complexity, and complex frequency composition (power spectrum). musical compositions also show novelty. it is significant that these simple analyses demonstrate these features in artistic productions, as this validates their interpretation as indicators of creativity in natural and socioeconomic processes. this also suggests that natural and mental processes share deep similarities. these hallmarks of creativity may be detected in series generated randomly, but they may also be generated causally. causal (non-random) creativity defines bios. we found empirically that symmetry , fundamental physical, biological and human processes are causal and creative. recursions such as the process equation at+ = at + k*t* sin(at) and the diversifying equation at+ = at + sin(k*t*at) generate a sequence of patterns as time t increases: equilibrium, periodicities, chaos, bios and leaps (figure ). these equations involve asymmetric action (recursion in time), bipolar opposition (sine function), and continuity (conserved term at). these three elements correspond to the defining properties of the three mother structures of mathematics (bourbaki): lattice asymmetry, group opposition, and topological continuous transformation of spatial form. these three elementary forms are also found by piaget in fundamental cognitive operations, in the three dimensions of the central nervous system [ ] and in many other physical, biological and human processes as illustrated by table . some of these may be mere analogies (as between the wing of a bird and the wing of an airplane) but we as hypotheses to be tested that many of them are homologies (as between the leg of a horse and the wing of a bird). we thus conceived the idea that these three forms – unidirectional flow of energy in asymmetric time (action), bipolar opposition such as the bidirectional communication of information by bidimensional and bipolar electromagnetic radiation, and tripolar, continuous transformation of tridimensional matter-- constitute basic principles of nature [ ]. this is process theory (table ). the study of literary and musical creations suggests that this theory extends to art. bourbaki’s three forms may thus provide a mathematical foundation for a theory of creative evolution and of artistic creation. the small numbers appear to capture some important aspects of bourbaki’s mother structures of mathematics: lattice asymmetry is unidirectional, group opposition is bidirectional, and space-like topological forms are tridimensional. we can identify these numerical forms in the three fundamental physical forces, unidirectional gravitation, bipolar and bidimensional electromagnetic force, and tri- polar nuclear forces that unite quarks to form protons and neutrons and thereby construct tridimensional atomic nuclei. more generally, action (energy * time) is asymmetric, information requires the distinction between two opposite entities, and matter is tridimensional. asymmetry and symmetry are the defining features of lattices and groups, two of the three fundamental mathematical structures described by bourbaki. lattice abstracts asymmetry and thereby one-dimensional order, which is physically embodied in the sequence of time, but every lattice has a dual (a a). logically and methodologically, we describe the priority of the simple and the supremacy of the complex as complementary, opposite asymmetries embodied in actual processes, a concept developed by considering the vertical organization of the central nervous system in the context of integrating biological, social and psychological aspects of medical diagnosis and treatment [ ], and also applicable to social issues [ ] and to scientific research [ ]. table . asymmetry and symmetry. asymmetry dyadic asymmetry and symmetry triadic asymmetry and symmetry integers examples of numerical form uni-directional time bi-polar and bi-dimensional electro-magnetic charge tri-polar nuclear forces numerical archetypes divine proportion φ = . … perfect circular symmetry: Π = . … e = . symmetry , table . cont. form asymmetry < opposition, asymmetric and symmetric triadicity bourbaki’s structures order: lattices group opposition and other algebras structure: d geometry physics action: energy flow in time communication (two-valued information: opposites) tri-dimensional matter physical forces gravitation (attraction) electromagnetic (attraction and repulsion) strong nuclear force creates structure. weak nuclear force creates asymmetry. light linear propagation sine wave color spatial radiation schrodinger equation energy, total e and potential u sine and cos. if e> u; sinh and cosh if e < u momentum = mass * velocity einstein equation e c m chemistry asymmetric molecules and biomolecules (pasteur) covalent and asymmetric carbons biology metabolism anabolism and catabolism. sexuality (linnaeus). organisms. mother, father and child. evolutionary theory life, survival, evolution competition and (darwin) and mutual aid (kropotkin) multicellularity, symbiosis, mutual aid, sociality central nervous system asymmetric dorsal- sensory to ventral motor axis quasi-symmetric right-left axis vertical axis from simple to complex physiology, medicine homeostasis: equilibrium. sympathetic and parasympathetic. periodicity. anatomy. social groups age, generations sexes. parent / child. master / slave. upper, middle and lower classes social aims/ organization health of persons and environment sexes. class cooperation (socialism) and competition (smith) and struggle (marx) executive, legislative and judicial powers economics consumption distribution, trade production psychology flux (james). action (moreno) conflict (freud). fight or flight (cannon). role reversal (moreno). id, ego, superego (freud). creativity: (moreno). conflict behaviors and emotions [ ]. cognition [ ] mental operations regarding order mental operations regarding classes mental operations regarding space education [ ] pragmatic emotional cognitive and artistic methodology priority of the simple and objective [ , ]. analyze synergy and conflict of opposites supremacy of the complex or the subjective [ , ]. research techniques time series phase plane of opposites [ ], trigonometric analysis n-dimensional recurrence symmetry , table . cont. dynamics asymmetric factor of catastrophes bifurcation. bifurcating factor of catastrophes form and transformation. complex patterns: fractal, chaos, bios. process philosophy process (not isolated events or stability) dialectic: coexisting, interacting, opposites. material embodiment. creative synthesis of opposites and triads. supremacy of complex logic / biotic logic implication. evolving concepts. mutual exclusion (aristotle, boole) and implication (sabelli) of opposites. triadic categories (hegel, pierce) and operations. process equation recursion: a(t + ) sin(a(t)) sequence of patterns: convergence, periodicity, chaos, bios music rhythm, tempo melody harmony algebras, such as group theory, are defined by the generation of new elements by the combination of existing ones. while lattice asymmetry represents order, group opposition is regarded as abstracting symmetry. simple reflection indicates that opposites can be perfectly symmetric ( and - ), largely symmetric (two sides of a human body) or largely asymmetric (proton and electron, women and men, beauty and ugliness). a group is a set in which element has an inverse or symmetric opposite. inverse elements annul each other when combining, returning to the information-less identity element. it is the combination of any other pair of elements (that are not symmetric) that generates a new element; this captures the creative interaction of opposites postulated by ancient process philosophers (heraclitus, empedocles, lao-tzu) as well as by modern theorists. many scientific disciplines, including physics, biology, sociology, and psychology, also explain the generation of complexity as resulting from the interaction of opposites. the third fundamental structure is modeled by topology, the study of space-like forms, their formation and transformation. material structures are tridimensional; correspondingly, topological knots are described by three ‘colors’. the human body itself shows temporal asymmetry in the dorsal- ventral axis, rough right-left symmetry, and the asymmetry of complexity in its vertical dimension. these three patterns also exist in the multiple levels of complexity that form the “vertical dimension” of nature from physical to mental processes. a hierarchy of complexity is also evident in the sequence of patterns generated by recursions such as the logistic, the process and the diversifying equations. indeed, symmetry and entropy decrease as the process equation enters the biotic phase. entropy is also relatively low in natural processes with a biotic pattern [ , ]. this may account for the development of complexity in physical and biological processes, so far justified by the local development of pockets of low entropy due to the selective intake of low entropy materials [ ] and the selective excretion of high entropy waste products [ , ]. in statistics, entropy measures the degree of symmetry [ - ], while information is the degree of asymmetry [ ]. according to classic thermodynamics, processes spontaneously flow towards higher entropy, i.e. from asymmetry to symmetry, and thereby towards equilibrium, and rest; actually symmetry , physical and biological evolution demonstrates that processes often spontaneously flow from symmetry to asymmetry. evolution increases information, and thereby generates complexity and beauty. symmetry is beautiful because it renders stability, asserts shu-kun lin [ ]; nevertheless, he adds, symmetry is in principle ugly because it is associated with information loss. from a different esthetic perspective, asymmetry is beautiful because it overcomes stability and drives evolution and the generation of complexity. symmetry is beautiful because it embodies order rather than decay, disorder and rest. high entropy implies complexity, not necessarily disorder. but also asymmetry contributes to order and beauty; in fact, the mathematical definition of order is lattice asymmetry, and the asymmetric divine or golden proportion φ = . … has been a cannon of beauty in architecture and painting since phidias. while the geometric symmetry of a face often conveys beauty, in reality human faces always show a degree of mathematical asymmetry, and their asymmetry contributes to esthetic pleasure. mathematical modeling demonstrates that bios is generated by recursions that involve both asymmetry and symmetry. opposites play a major role in creative evolution, artistic creativity, and beauty, rather than annulling each other in featureless thermodynamic equilibrium. asymmetry and symmetry are evident contributors to beauty, which is a major component of our emotional life and of art. both art and life also involve creative processes that transform simple forms to generate complexity. indeed, beauty requires complexity, because it may exist in simple as well as complex patterns, but it is perceived only by relatively complex organisms (e.g. mate selection, bees and birds attraction to flowers, etc.). here we find in art bourbaki’s three generative forms, the asymmetry that defines lattices, the symmetry of opposites that defines groups, and the topological transformation of simple forms into complex ones. bourbaki’s concepts provide a way to formulate the notion of causal, non-random creativity in an exact manner. causal creativity represents an alternative to the theological concept of creation of matter from the void, classic determinism in which causality is not creative, and the current models of random variability in theories of the early universe, quantum mechanics, biological evolution by random mutation, and stochastic markets that offer no way to understand or influence processes. in contrast to portraits of change and creativity as “noise”, the observation of bios from quantum mechanics to music supports pythagoras and kepler’s perspective in which music is a model for the mathematics of the universe. in summary, both natural and artistic creative processes display asymmetry, symmetry, and creative transformation, indicating a common, possibly fractal, process (bios) extending from quantum entities to mental activity. acknowledgements we are thankful to the society for the advancement of clinical philosophy and to mrs. maria mccormick for their support. references . anderson, p.w. more is different. science , , - . symmetry , . bourbaki, n. 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(in press). symmetry , . schrödinger, e. what is life? the physical aspect of the living cell; the macmillan company: new york, ny, usa, . . prigogine, i. from being to becoming: the new science of connectedness; doubleday: new york, ny, usa, . . prigogine, i. the end of certainty; the free press: new york, ny, usa, . . cohen j.; steward, i. the collapse of chaos; penguin: new york, ny, usa, . . leyton, m. symmetry, causality, mind; mit press: cambridge, uk, . . petitjean, m. order, entropy and symmetry: an awkward relation? symmetry cult. sci. , , - . . jakulin, a.. symmetry and information theory. symmetry cult. sci. , , - . . matsuno, k. symmetry and information: symmetry as an emergent property of information. symmetry cult. sci. , , - . . smith, a. a hierarchical perspective. symmetry cult. sci. , , - . . salthe, n. asymmetry and self-organization. symmetry cult. sci. , , - . . darvas, g. order, entropy and symmetry. symmetry cult. sci. , , - . . lin, s.k. the nature of the chemical process. . symmetry evolution—revised information theory, similarity principle and ugly symmetry. int. j. mol. sci. , , - . © by the authors; licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution license (http://creativecommons.org/licenses/by/ . /). beautiful conjectures in graph theory adrian bondy what is a beautiful conjecture? the mathematician’s patterns, like the painter’s or the poet’s must be beautiful; the ideas, like the colors or the words must fit together in a harmonious way. beauty is the first test: there is no permanent place in this world for ugly mathematics. g.h. hardy some criteria: . simplicity: short, easily understandable statement relating basic concepts. . element of surprise: links together seemingly disparate concepts. . generality: valid for a wide variety of objects. . centrality: close ties with a number of existing theorems and/or conjectures. . longevity: at least twenty years old. . fecundity: attempts to prove the conjecture have led to new concepts or new proof techniques. reconstruction conjecture p.j. kelly and s.m. ulam every simple graph on at least three vertices is reconstructible from its vertex-deleted subgraphs stanislaw ulam simple surprising general central old f ertile ∗∗ ∗ ∗ ∗ ∗ ∗ ∗ psfrag replacements v v v v v v g − v g − v g − v g − v g − v g − v g edge reconstruction conjecture f. harary every simple graph on at least four edges is reconstructible from its edge-deleted subgraphs frank harary simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗∗ ∗ psfrag replacements g g h h main facts reconstruction conjecture false for digraphs. there exist infinite families of nonreconstructible tournaments. p.j. stockmeyer edge reconstruction conjecture true for graphs on n vertices and more than n log n edges. l. lovász , v. müller path decompositions t. gallai every connected simple graph on n vertices can be decomposed into at most (n + ) paths tibor gallai simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗∗ ∗∗ circuit decompositions g. hajós every simple even graph on n vertices can be decomposed into at most (n − ) circuits györgy hajós simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗∗ ∗∗ hamilton decompositions p.j. kelly every regular tournament can be decomposed into directed hamilton circuits. simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗∗ ∗ main facts gallai’s conjecture true for graphs in which all degrees are odd. l. lovász hajós’ conjecture true for planar graphs and for graphs with maximum degree four. j. tao , kelly’s conjecture claimed true for very large tournaments. r. häggkvist (unpublished) circuit double cover conjecture p.d. seymour every graph without cut edges has a double covering by circuits. paul seymour simple surprising general central old f ertile ∗ ∗ ∗ ∗∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ small circuit double cover conjecture jab every simple graph on n vertices without cut edges has a double covering by at most n − circuits. jab simple surprising general central old f ertile ∗ ∗ ∗ ∗∗ ∗ ∗ ∗ ∗∗ ∗ ∗ cycle double cover conjecture m. preissmann every graph without cut edges has a double covering by at most five even subgraphs myriam preissmann simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗∗ ∗ ∗ psfrag replacements g h petersen graph matching double cover conjecture r.d. fulkerson every cubic graph without cut edges has a double covering by six perfect matchings reformulation: cycle quadruple cover conjecture f. jaeger every graph without cut edges has a quadruple covering by six even subgraphs simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗∗ ∗ ∗∗ ∗ main facts circuit double cover conjecture if false, a minimal counterexample must have girth at least ten. l. goddyn small circuit double cover conjecture true for graphs in which some vertex is adjacent to every other vertex. h. li cycle double cover conjecture true for -edge-connected graphs. p.a. kilpatrick , f. jaeger true for various classes of snarks. u. celmins cycle quadruple cover conjecture every graph without cut edges has a quadruple covering by seven even subgraphs. j.c. bermond, b. jackson and f. jaeger five-flow conjecture w.t. tutte every graph without cut edges has a -flow bill tutte simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ psfrag replacements psfrag replacements three-flow conjecture w.t. tutte every -edge-connected graph has a -flow bill tutte simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗∗ ∗∗ ∗ ∗ ∗ weaker conjecture: weak three-flow conjecture f. jaeger, there exists an integer k such that every k-edge-connected graph has a -flow main facts five-flow conjecture every graph without cut edges has a -flow. p.d. seymour three-flow conjecture every -edge-connected graph has a -flow. f. jaeger directed cages m. behzad, g. chartrand and c.e. wall every d-diregular digraph on n vertices has a directed circuit of length at most dn/de extremal graph for d = dn/ e (directed triangle) simple surprising general central old f ertile ∗∗ ∗ ∗ ∗∗ ∗∗ second neighbourhoods p.d. seymour every digraph without -circuits has a vertex with at least as many second neighbours as first neighbours paul seymour simple surprising general central old f ertile ∗∗ ∗∗ ∗ ∗ ∗ ∗ ∗ psfrag replacements v the second neighbourhood conjecture implies the case d = ⌈n ⌉ of the directed cages conjecture: psfrag replacements v dd ≥ d if no directed triangle n ≥ d + > n main facts behzad-chartrand-wall conjecture every d-diregular digraph on n vertices has a directed circuit of length at most n/d + . v. chvátal and e. szemerédi true for d ≤ . c. hoàng and b.a. reed every cn-diregular digraph on n vertices with c ≥ . has a directed triangle. m. de graaf second neighbourhood conjecture true for tournaments. j. fisher , f.havet and s. thomassé chords of longest circuits c. thomassen every longest circuit in a -connected graph has a chord carsten thomassen simple surprising general central old f ertile ∗ ∗ ∗ ∗∗ ∗ ∗ smith’s conjecture s. smith in a k-connected graph, where k ≥ , any two longest circuits have at least k vertices in common scott smith simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ hamilton circuits in line graphs c. thomassen every -connected line graph is hamiltonian carsten thomassen simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ ∗ hamilton circuits in claw-free graphs m. matthews and d. sumner every -connected claw-free graph is hamiltonian simple surprising general central old p rolif ic ∗ ∗ ∗∗ ∗ main facts thomassen’s chord conjecture true for bipartite graphs. c. thomassen scott smith’s conjecture true for k ≤ . m. grötschel thomassen’s line graph conjecture line graphs of -edge-connected graphs are hamiltonian. c. thomassen every -connected line graph is hamiltonian. s.m. zhan hamilton circuits in regular graphs j. sheehan every simple -regular graph with a hamilton circuit has a second hamilton circuit john sheehan simple surprising general central old f ertile ∗ ∗ ∗ ∗∗ ∗ ∗ ∗∗ an interesting graph used by fleischner to construct a -regular multigraph with exactly one hamilton circuit. finding a second hamilton circuit m. chrobak and s. poljak given a hamilton circuit in a -regular graph, find (in polynomial time) a second hamilton circuit marek chrobak and svatopluk poljak simple surprising general central old f ertile ∗ ∗ ∗ ∗ ∗ ∗ ∗ hamilton circuits in -connected graphs h. fleischner every -connected graph with a hamilton circuit has a second hamilton circuit herbert fleischner simple surprising general central old f ertile ∗ ∗ ∗ ∗∗ ∗ ∗ main facts sheehan’s conjecture every simple -regular graph with a hamilton circuit has a second hamilton circuit. c. thomassen there exist simple uniquely hamiltonian graphs of minimum degree four. h. fleischner fleischner’s conjecture true for planar graphs. w.t. tutte what is a beautiful theorem? mathematics, rightly viewed, possesses not only truth, but supreme beauty – a beauty cold and austere, like that of sculpture. bertrand russell some criteria: . simplicity: short, easily understandable statement relating basic concepts. . element of surprise: links together seemingly disparate concepts. . generality: valid for a wide variety of objects. . centrality: close ties with a number of existing theorems and/or conjectures. . fecundity: has inspired interesting extensions and/or generalizations. . correctness: a beautiful theorem should be true! what is a beautiful proof? . . . an elegant proof is a proof which would not normally come to mind, like an elegant chess problem: the first move should be paradoxical . . . claude berge claude berge some criteria: . elegance: combination of simplicity and surprise. . ingenuity: inspired use of standard techniques. . originality: introduction of new proof techniques. . fecundity: inspires new proof techniques or new proofs of existing theorems. . correctness: a beautiful proof should be correct! most beautiful conjecture j.a.b. dominic will continue to prove and conjecture for many years to come happy birthday, dominic! http://www.genealogy.math.ndsu.nodak.edu wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need 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" / " „ДА ЛИЦЕ ПОСТАНЕ ЛЕПО” (Цртица о средњовековној козметици)* Средњовековни људи су имали амбивалентан однос према козметици: једни су подржавали покушаје улепшавања и дотеривања, док су други, пре свега представници цркве, на таква настојања гледали негативно. У овом прилогу узети су савети и рецепти за улепшавање из два меди- цинска зборника састављена у позном средњем веку. У питању су један византијски медицински трактат (xi–xiv век) и један зборник српске средњовековне медицине, тзв. Ходошки зборник. У овим зборницима се могу наћи савети како да лице буде бело, коса црна или плава, али свакако густа, потом рецепти против бора, брадавица, пега, испуцалих усана или непријатног задаха. У добро познатој епизоди са путовања Бертрандона де ла Брокијера „преко мора” ( / ) и његове посете Цариграду бургундски витез је био фасциниран изузетном лепотом Марије Комнине Палеологине, ћерке трапезунтског цара Алексија iv Великог Комнина ( – ) и треће супруге византијског цара Јована viii Палеолога ( – ). Њеној лепоти, додајмо, није одолео ни велики мајстор ране ренесансе Антонио Пизанело који је тридесетих година xv века на фресци у цркви Свете Анастасије у Верони овековечио царичин лик. Међутим, Брокијер је Ма- рији Комнини Палеологини ипак замерио то што се шминка „за што није било потребе јер је била млада и бела”. Овакво гледиште бургундског витеза отвара занимљиво питање о односу средњовековних људи према козметици. Одмах треба рећи да је став који је homo medievalis имао по том питању у најмању руку био амбивалентан. Када је реч о Византији, на једној страни имамо царицу Зоју која је подесан пример за афирмативан * Овај рад је настао на пројекту бр. под насловом „Хришћанска култура на Балкану у средњем веку: Византијско царство, Срби и Бугари од . до . века” који финансира Министарство просвете, науке и технолошког развоја Републике Србије. a. bryer, pisanello and the princess of trebizond, apolo n. s. ( ) - . Бертрандон де ла Брокијер, Путовање преко мора, прев. М. Рајичић, Београд , , . Радивој Радић став према козметици. У питању је кћи византијског цара Константина viii Палеолога ( – ) познате и по томе да се страсно занимала за справљање мириса и козметичких средстава које су за њу поручивали из далеких земаља, Етиопије и Индије. У женском одељењу царске палате, где је Зоја проводила највећи део времена, целе године буктале су ватре за справљање помада и парфема које јој је правила њена послуга. Отуда је гинекеј, дакле женско одељење царске палате, више личио на хемијску лабораторију, него на дворац императора. Међутим, на другој страни су поједини црквени оци, Јован Златоусти, на пример, који је био изразити противник женског улепшавања, дотеривања и накита. Штавише, у xv веку је Јован Евгеник саставио памфлет против жена које пудеришу своје лице, боје усне, руменилом прекривају образе и црном бојом наглашавају обрве да би постале лепше и привлачније. Како било, не може се порећи чињеница да су се људи од памтивека старали о свом физичком изгледу и да су, користећи разнолика козметичка средства, тежили властитом улепшавању. Значи да је питање улепшавања заправо ванвременско и да је присутно у свим епохама људске историје, а мењала су се једино средства, мада и она само делимично. Тако, на пример, знаменити учењак Плиније Старији из i века у свом спису Позна- вање природе (naturalis historia) доноси занимљив рецепт о улепшавању и истиче како се сматра да млеко магарице уклања боре са лица и кожу чини белом и меканом. Уз то, он истиче како је добро познато да неке жене свакога дана по седам пута, ревносно се придржавајући тог броја, умивају своје образе. Диоскоридис, Плинијев нешто старији савреме- ник, истиче да су жене своју кожу неговале тако што су је премазивале маслиновим уљем из пелопонеског града Сикиона. У наставку ћемо дати рецепте који иду у прилог улепшавању, а сачувани су у два позносредњовековна медицинска зборника, у визан- тијском медицинском трактату (xi–xiv век) и у тзв. Ходошком зборни- ку, терапијском зборнику српске средњовековне медицине с краја xiv А. А. Чекалова, Быт и нравы, у: Культура Византии. Вторая половина vii – xii в., ред. З. В. Удальцова, Г. Г. Литаврин, Москва , . Ш. Дил, Византијске слике, прев. О. Косановић, Београд , - . А. А. Чекалова, Быт и нравы византийского общества, у: Культура Византии. iv – первая половина vii в., ред. З. В. Удальцова, Москва , . s. eustratiades, peri kosmoseos ton byzantinon, epeteris hetaireias byzantinon spoudon ( ) - . pliny, natural history, vol. viii, libri. xxviii–xxxii, by w. h. s. jones, cambridge (mass.) – london , . the oxford dictionary of byzantium, ed. a. p. kazhdan, vol. i, new york – oxford , . Г. Г. Литаврин, Византийский медицинский трактат xi–xiv вв., Санкт-Петербург , - (= Византийский медицинский трактат). „Да лице постане лепо” или почетка xv века, у којем се налази мешовита медицинска грађа. Упадљиво је, али не и изненађујуће, да је у оба случаја реч о медицин- ским зборницима. Упркос чињеници да је у односу на античку медицину – која је пак много дуговала медицини древног Египта – византијско лекарство доживело одређену осеку, не може се порећи да су ромејски лекари на извесним пољима унапредили постојећа знања. Византинци су искази- вали посебну пажњу медицини, али их је пре свега интересовала њена практична страна. Отуда не треба да изненађује чињеница да византијска медицина није знатније унапредила теоријску основу ове дисциплине јер се слабо бавила анатомијом, физиологијом и патологијом. С друге стране, она је у великој мери усавршила вештину дијагностике и терапије, као и хируршку оперативну технику, фармакопеју и фармацију. Уверљиво сведочанство о дометима византијске медицине, а поготово њеног дела који се тиче фармакологије и фармакопеје, односно приправљања лекова, представља један текст који је састављен у позновизантијском раздобљу. Реч је о анонимном медицинском трактату, заправо лекарском зборнику који је служио за практичну употребу, о својеврсној енциклопедији која је делом компилација, а делом оригинални текст. Саставио ју је очигледно искусан лекар који се није либио да у текст унесе и властита сазнања стечена дугогодишњом праксом. Медицински трактат се датује у широк временски период од средине xi до друге половине xiv века, и на основу досадашњих сазнања није могуће сузити овај велики временски одсек. Трактат је више окренут практичним саветима него напоменама од ширег теоријског значаја и у њему одељак посвећен фармакологији заузима највећи део. У Византији фармакологија није постојала као независна научна грана, што значи да су византијски лекари били и у исто време и апотекари и фармацеути који сами скупљају лековите траве и из њих справљају лекове. Анонимни састављач византијског медицинског трактата се стара о онима који су имали боре, што им је тешко падало, и предлаже им по- ступак којим се оне могу уклонити. Било је потребно најпре ноћу лице намазати сирћетом у коме су растворени половина унце костоса, четврт Р. В. Катић, Терапијски зборници српске средњовековне медицине и њихово поре- кло, Археографски прилози ( ) - (= Катић, Терапијски зборници); Р. В. Катић, Медицински списи Ходошког зборника. Избор, Београд , (= Ходошки зборник). o. temkin, byzantine medicine. tradition and empiricism, dumbarton oaks papers ( ) – ; h. hunger, die hochsprachliche profane literatur der byzantiner, ii, münchen , – ; symposium on byzantine medicine, dumbarton oaks papers ( ) - . З. Г. Самодурова, Естественнонаучные знания, у: Культура Византии. iv – первая половина vii в., ред. З. В. Удальцова, Москва , - . Византийский медицинский трактат, - . З. Г. Самодурова, Естественнонаучные знания, у: Культура Византии. Вторая половина vii – xii в., ред. З. В. Удальцова, Г. Г. Литаврин, Москва , . Радивој Радић унце сувих корица диње и четврт унце смоле, а после тога је требало лице отрти брашном од сочива. Унца (oyggia) је мера за тежину и из- носи , грама. Истовремено, корисним за борбу против бора сматрао се раствор семена роткве са горким бадемом у старом вину. Овај лек је, додаје састављач, био делотворан и за лишаје на телу. Аутор медицинског трактата је имао рецепте и за оне који су се бринули о својој коси. Ако неко хоће да његова коса буде црна, односно ако је оседео и хоће то да прикрије, саветује он, потребно је да их намаже соком од сасе, односно шумарице (грч. ἀνεμώνη) и да их трећег дана опере топлом водом. Уколико се, пак, жели да коса буде плава онда треба узети уситњени талог прокуваног вина, додати му уз мешање смолу борове шишарке, у размери половине талога, све то растворити у ружином уљу и намазати косу, а трећег дана је опрати. Ако женама опада коса, бележи именом непознати аутор трактата, треба по глави посипати следећу мешавину: меснати део бобица од кле- ке ( унце), кипариса печеног и просејаног ( унце), ириса иситњеног и просејаног ( унце), куркуме ( унца) и ловоровог плода ( унце). С друге стране, да би коса била густа треба је прати мешавином пене морске воде и мирне (тамјана). За оне који су имали бео тен, а да би лепо изгледали требало је одвоје- но иситнити бакарну стипсу и кентаурион (centaurea solonitana), а онда их помешати и дати да се добијена мешавина пије у току петнаест дана. Лепоту белог лица нарушавале су пеге, а да би се оне отклониле требало је најпре спаљену љуштура сипе или мурекса (пурпурног пужа) или кирикона (врста крупне морске сипе чија се љуштура употребљавала као труба) премазати медом. Потом је све то требало ставити у земљани лонац и дати да се пече у пећи. Састаављач трактата у наставку бележи да ово средство делује и против младежа. Против брадавица се препоручује смеса у којој ће се наћи равно- мерно иситњен арсеник (заправо арсеников црвени сумпор) и со, којима треба додати и теревинта (pistacia terebinthus). Непријатни задах из уста може човеку проузроковати низ невоља и довести га у неугодну ситуацију. Против непријатног задаха препору- Византийский медицинский трактат, . e. schilbach, byzantinische metrologie, münchen , - ; Византийский медицинский трактат, н. . Византийский медицинский трактат, . Исто, . Исто, . Исто, . Исто, . Исто, . Исто, . Исто, . „Да лице постане лепо” чује се жвакање метвице (mentha) или семена целера, или ватона (rubus ulmifolius) или лишћа винове лозе. Напослетку уста треба испрати ми- ришљавим вином. Помаже и сажежени осат, односно бодаљ, (sonchus aspera), после кога је, такође, потребно уста исплакнути миришљавим вином. Ако су уста испуцала, препоручује састављач медицинског трактата, потребно је иситнити крљ, односно скочац (ricinus communis) и исопом (origanum hirtum) и помешати са медом, па тиме намазати усне. Када се говори о медицини код Срба у Средњем веку ваља нагла- сити да се у њој могу разликовати најмање три засебна тока који су се међусобно сучељавали, преплитали и допуњавали. Први ток чинило је лекарство које су Срби донели из своје прадомовине, а то је рудиме- нтарна словенска медицина. Постојање многобројних старих назива за поједине делове тела и важније органе недвосмислено казује о прилично добром познавању анатомије међу старим Словенима. У средњовековној Србији се познавање медицине осим на основама древног словенског лекарства развијало и под веома снажним утицајима који су долазили из Византије. Наравно, добро је познато да је српска средњовековна култура у највећој мери проистекла из окриља префињене и надмоћне византијске цивилизације. И, напослетку, трећи беочуг у стварању оног што можемо означити као српска средњовековна медицина чине утицаји који су преко приморских градова на источној обали Јадранског мора, Котора и Дубровника пре свега, долазили из Италије и других западних земаља. Управо је утицај који је долазио са Апенинског полуострва бивао све јачи што се Средњи век ближио своме заласку. Један од најважнијих зборника српске средњовековне медицине је тзв. Ходошки зборник. У питању је терапијски зборник с краја xiv или почетка xv века, у којем се налази мешовита медицинска грађа. За лепоту лица, сугерише аутор Ходошког зборника, треба приме- нити следећи поступак: „Помешај гушчије сало са сезамовим уљем и пошто ову мешавину отопиш њоме често мажи лице и оно ће постати лепо (подмладиће се)”. Попут аутора византијског медицинског трактата, и састављач Ходошког зборника има неколико савета о томе како се може уклонити непријатни задах. Он даје следеће препоруке: „Са копитњаком скуваном у вину испирај уста” , „Спали суво лишће од ружиног цвета, затим то Исто, . Исто, . Р. В. Катић, Медицина код Срба у средњем веку, Београд , сл.; Р. В. Катић, Српска медицина од ix до xix века, Београд , сл. Катић, Терапијски зборници, - . Ходошки зборник, . Исто, . Радивој Радић иситни у прах и тиме трљај зубе” , „Помешај мед са топлом водом и тиме испирај уста. Уместо тога може се узимати и загрејан мед”, „Скувај мекиње у води, затим из њих исцеди течност и са том течношћу испирај уста”. Белина зуба, праћена осмехом, увелико доприноси лепоти лица, па у Ходошком зборнику можемо прочитати: „Јелењи рог треба палити све док не постане сасвим бео, затим га иситни тако да буде сличан брашну и тим прахом мажи зубе”. Поводом бубуљица на лицу, које могу увелико нарушити његову лепоту, препоручују се следећи третмани: „Иситни мрамор у прах, поме- шај га са беланцетом од јајета и са тиме мажи лице” , „Иситни корен од крина, на то после додај оцат и тиме мажи лице. Затим узми псамиду и суву балегу од ластавице, помешај их заједно и тиме мажи. Све ово што сам споменуо важи и за лечење старих краста и лишаја”. За византијски медицински трактат и зборник српске средњовековне медицине може се рећи да су занимљива комбинација сериозно писаних практичних приручника, у којима постоје и нека теоретска образложења медицине као научне дисциплине, али и текстова у којима се, додуше у сасвим невеликој мери, такође налазе и савети натопљени сујеверјем. Очигледно је да су се њихови састављачи ослањали на списе својих прет- ходника, с једне, али, у случају именом непознатог византијског аутора, с друге стране, и на сопствену вишегодишњу праксу. Радивој Радић Кључне речи: Византија, козметика, Србија, медицина, лице, медицински трактат, Ходошки зборник, лепота, рецепт. Исто. Исто, . Исто. Исто, . Исто, . Исто. С. Н. Гукова, Естественнонаучные знания в палеологовский период, у: Культура Византии. xiii – первая половина xv в., ред. Г. Г. Литаврин, Москва , . „Да лице постане лепо” radivoj radić “making the face beautiful” (feature on medieval beauty products) in the middle ages, people had an ambivalent relationship to the beauty products: some were fully supportive of the attempts to beautify oneself, while the others, first and foremost the representatives of the church, frowned upon this notion. this feature represents a show- case of the advice and recipes for beautification from two medical collections created in the late middle ages. these are the byzantine medical treatise (dating from th to th century) and the collection of serbian medieval medicine, the so-called hodoch code (dating from the end of the th or beginning of the th century). the treatise is focusing more on the practical advice than theoretical knowledge, and its greatest part is dedicated to pharmacology. hodoch code (hodoški zbornik) is in fact a therapeutic collection, and it consists of diverse medical texts. these collections contain the advice how to make one’s face white, hair black or blond, but most certainly rich in volume, as well as recipes for treating facial lines, warts, freckles, cracked lips or bad breath. http://pss.sagepub.com/ psychological science http://pss.sagepub.com/content/ / / the online version of this article can be found at: doi: . / : originally published online october psychological science andrew edward white, douglas t. kenrick and steven l. neuberg beauty at the ballot box: disease threats predict preferences for physically attractive leaders published by: http://www.sagepublications.com on behalf of: association for psychological science can be found at:psychological scienceadditional services and information for http://pss.sagepub.com/cgi/alertsemail alerts: http://pss.sagepub.com/subscriptionssubscriptions: http://www.sagepub.com/journalsreprints.navreprints: http://www.sagepub.com/journalspermissions.navpermissions: what is this? - oct , onlinefirst version of record - dec , version of record >> at university of missouri-columbia on january , pss.sagepub.comdownloaded from at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ http://pss.sagepub.com/content/ / / http://pss.sagepub.com/content/ / / http://www.sagepublications.com http://www.sagepublications.com http://www.psychologicalscience.org/ http://www.psychologicalscience.org/ http://pss.sagepub.com/cgi/alerts http://pss.sagepub.com/cgi/alerts http://pss.sagepub.com/subscriptions http://pss.sagepub.com/subscriptions http://www.sagepub.com/journalsreprints.nav http://www.sagepub.com/journalsreprints.nav http://www.sagepub.com/journalspermissions.nav http://www.sagepub.com/journalspermissions.nav http://pss.sagepub.com/content/ / / .full.pdf http://pss.sagepub.com/content/ / / .full.pdf http://pss.sagepub.com/content/early/ / / / .full.pdf http://pss.sagepub.com/content/early/ / / / .full.pdf http://online.sagepub.com/site/sphelp/vorhelp.xhtml http://online.sagepub.com/site/sphelp/vorhelp.xhtml http://pss.sagepub.com/ http://pss.sagepub.com/ http://pss.sagepub.com/ http://pss.sagepub.com/ psychological science ( ) – © the author(s) reprints and permissions: sagepub.com/journalspermissions.nav doi: . / pss.sagepub.com research article in the fall of , john f. kennedy and richard nixon faced off in the closest presidential election of the th century—with a mere . % separating the two candi- dates in the national popular vote. although many sub- stantive issues separated the candidates, historians agree that a seemingly stylistic difference, the physical appear- ance of kennedy during the first presidential debate, was a major turning point in the campaign. whereas kennedy appeared handsome and fit, nixon seemed pale and sickly (kraus, ). anecdotal reporting on the debate highlighted the consequences of the candidates’ contrast- ing appearances: those who watched the debate on tele- vision seemed to think kennedy was the winner; those who had listened to the debate only on the radio, and had not seen the candidates, perceived nixon to be the victor (germond & witcover, ). in recent years, a number of empirical studies have supported the notion that physical appearance can affect voting preferences. in both laboratory experiments and examinations of real voting behavior, people are more likely to vote for physically attractive candidates (e.g., banducci, karp, thrasher, & rallings, ; berggren, jordahl, & poutvaara, ; budesheim & depaola, ; rosenberg, bohan, mccafferty, & harris, ). in gen- eral, this phenomenon has been attributed to people’s tendency to ascribe positive characteristics to those who are physically attractive and, the thinking goes, that these generally positive attributions drive voting behavior. we suggest another explanation—that preferences for physi- cally attractive leaders may be related to functional dis- ease-avoidance mechanisms. adopting this perspective in the current investigation, we derived and tested novel pssxxx . / white et al.disease threats and leadership preferences research-article corresponding author: andrew edward white, department of psychology, arizona state university, s. mcallister dr., tempe, az e-mail: aewhite @asu.edu beauty at the ballot box: disease threats predict preferences for physically attractive leaders andrew edward white, douglas t. kenrick, and steven l. neuberg arizona state university abstract why does beauty win out at the ballot box? some researchers have posited that it occurs because people ascribe generally positive characteristics to physically attractive candidates. we propose an alternative explanation—that leadership preferences are related to functional disease-avoidance mechanisms. because physical attractiveness is a cue to health, people concerned with disease should especially prefer physically attractive leaders. using real-world voting data and laboratory-based experiments, we found support for this relationship. in congressional districts with elevated disease threats, physically attractive candidates are more likely to be elected (study ). experimentally activating disease concerns leads people to especially value physical attractiveness in leaders (study ) and prefer more physically attractive political candidates (study ). in a final study, we demonstrated that these findings are related to leadership preferences, specifically, rather than preferences for physically attractive group members more generally (study ). together, these findings highlight the nuanced and functional nature of leadership preferences. keywords evolutionary psychology, decision making, physical appearance, preferences, social structure received / / ; revision accepted / / at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ white et al. hypotheses about when and why people prefer physi- cally attractive leaders. an evolutionary approach to leadership humans are a social species, and to function effectively, people must often coordinate their behavior with one another. a seemingly universal means of achieving that coordination is through leader-follower relationships (van vugt, hogan, & kaiser, ). indeed, such relationships emerge spontaneously and quickly in group settings (bales, ; van vugt & de cremer, ) and even arise in groups of -year-old children (hawley, ). although leadership is considered a “universal” aspect of human social groups, this does not mean that leader- ship preferences are invariant. rather, a functional-evolu- tionary perspective suggests that leadership preferences should shift as a function of the unique set of threats and opportunities facing a group: groups that face different types of adaptive challenges should seek different types of leaders. in line with this thinking, several studies have demon- strated that leadership preferences shift in response to physical-safety threats. for example, during periods of intergroup conflict, people especially prefer charismatic, masculine, and dominant leaders (cohen, solomon, maxfield, pyszczynski, & greenberg, ; kosloff, greenberg, weise, & solomon, ; little, burriss, jones, & roberts, ; re, debruine, jones, & perrett, ). extending these findings, van vugt and spisak ( ) showed that intergroup conflicts influence leadership preferences differently than intragroup conflicts. during periods of intergroup conflict, when concerns about intergroup aggression are raised, people prefer male leaders, but during intragroup conflicts, when concerns about group cohesion come to the fore, people prefer female leaders. together, the results from these studies suggest that different leadership preferences emerge in response to different physical-safety threats. in the cur- rent investigation, we considered how another type of threat, that posed by infectious disease, can affect leader- ship preferences. disease threats and physical attractiveness for millions of years, humans have faced a strong, persis- tent threat from disease (wolfe, dunavan, & diamond, ) and, in response, have evolved defenses to prevent and combat infection. increasingly, researchers have examined the role of psychological and behavioral responses in preventing diseases from entering the body (schaller & park, ). for instance, people are espe- cially likely to pay attention to those with disfigurements (ackerman et al., ) and to associate benign physical abnormalities with contagious disease (e.g., park, faulkner, & schaller, ; park, schaller, & crandall, ). concerns about disease have also been linked to the stigmatization and avoidance of individuals who have heuristic cues of illness, such as deformities, lesions, obe- sity, physical disabilities, and facial asymmetry (e.g., park et al., , ; schaller & neuberg, ). physical attractiveness is also used as a heuristic cue to health status. ratings of facial attractiveness are highly correlated with perceptions of health (e.g., grammer & thornhill, ; rhodes, ; thornhill & gangestad, ), and some research has suggested that physical attractiveness might be a diagnostic (if imperfect) cue to actual health outcomes (gangestad, thornhill, & yeo, ; henderson & anglin, ; rhodes et al., ). for instance, in one study, attractive participants, relative to unattractive participants, displayed greater cardiovas- cular health and had fewer cold symptoms over a -month period (shackelford & larsen, ). disease threats and leadership preferences there are several reasons to believe that disease threats will increase preferences for a healthy leader. first, group members are relatively more dependent on leaders than on other group members, and groups with effective lead- ers are more successful than those with ineffective lead- ers (van vugt et al., ). thus, the costs of a leader becoming ill (and less effective) would be much larger than the costs of a typical other member becoming ill. moreover, if an unhealthy leader were to die, periods of leadership transition could interfere with intragroup coordination and create group instability—adversely affecting the ability of the group to meet its members’ needs. on this reasoning, we posit that people should prefer healthy leaders and that this preference should be exag- gerated during periods of disease threat. because physi- cal attractiveness can serve as a cue of health, we propose that people concerned with disease should especially favor physically attractive leaders. further, this relation- ship should be unique to disease threats, compared with other types of threats (e.g., physical-safety threats), because robust health is especially important during peri- ods of illness and disease. we tested these hypotheses in a series of four studies using both correlational data on real-world voting behavior and laboratory-based experi- ments. in study , we examined the relationship between disease threats and the outcomes of u.s. congressional at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ disease threats and leadership preferences elections. in studies and , we manipulated the pres- ence of disease threats and measured both stated prefer- ences for physically attractive leaders and inclinations to vote for physically attractive politicians. finally, in study , we tested whether the relationship between disease threats and leadership preferences reflects a general bias for preferring physically attractive people—in all aspects of one’s life—or whether this relationship is more impor- tant for those in leadership positions. study : disease threats and congressional elections method in study , we examined the relationship between dis- ease threats and preferences for physically attractive leaders at the national level. to do so, we gathered pho- tos of major-party candidates (winners and losers) from the u.s. congressional elections. an independent group of research assistants ( women, men) rated each photo using a scale from (extremely unattractive) to (extremely attractive). we also collected information about election results, each candidate’s political affilia- tion, and each candidate’s incumbent status. finally, we obtained data on disease threat in each congressional district using measures of infant mortality rate and life expectancy. these indicators are considered to be highly sensitive proxy measures of population health (murray, salomon, & mathers, ) and correlate with health out- comes (reidpath & allotey, ). in our data set, infant mortality rate and life expectancy were correlated, r( ) = −. . therefore, we z-scored each variable and combined these scores to create a disease-threat composite. results and discussion candidates’ political affiliation and incumbent status accounted for a large percentage of variance in voting patterns. in our analyses, we conducted a hierarchical regression in which we entered political affiliation and incumbent status in the first step and disease threat, physical attractiveness, and their interaction in the sec- ond step. for results from a full regression analyses, see study : additional analyses in the supplemental material available online. we regressed the percentage of votes each candidate received onto political affiliation, incumbent status, dis- ease threat, physical attractiveness, and the disease threat × physical attractiveness interaction. replicating previous results, physical attractiveness was positively related to percentage of votes, t( ) = . , p = . , β = . . as predicted, there was also a marginally signifi- cant interaction between disease threat and physical attractiveness, t( ) = . , p = . , β = . (see fig. ). next, we assessed the relationship between phys- ical attractiveness and percentage of votes at standard deviation above and below the mean of disease threat. in districts with high disease threat ( standard deviation above the mean), physical attractiveness significantly predicted vote percentage, t( ) = . , p = . , β = . . however, in districts with low disease threat ( stan- dard deviation below the mean), it did not (p > . ). stated another way, in districts with high disease threat, a -sd increase in physical attractiveness increased a can- didate’s total percentage of votes by . %. in districts with low disease threat, a -sd increase in physical attractiveness increased a candidate’s total percentage of votes by . %. in a second set of analyses, we examined what might be considered the most important electoral outcome— whether a candidate won or lost. a logistic regression revealed a significant interaction between disease threat and physical attractiveness, b = . , wald χ ( ) = . , p = . . in districts with high disease threat, physical attractiveness significantly predicted whether a candidate won or lost, b = . , wald χ ( ) = . , p < . ; in districts with low disease threat, it did not, p > . . stated another way, in districts with high disease threat, a -sd increase in physical attractiveness increased a candidate’s odds of winning by a factor of . . in districts with low disease threat, a -sd increase in physical attractive- ness decreased a candidate’s odds of winning by a factor of . . % % % % % % % % low high pe rc en ta ge o f v ot es disease threat low high physical attractiveness fig. . results from study : mean percentage of votes that u.s. congressional candidates received as a function of disease threat and attractiveness. low and high levels of disease threat and physical attrac- tiveness were standard deviation above and below the mean, respec- tively. error bars indicate standard errors of the mean. at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ white et al. we also tested whether our results (a) were consistent across both male and female candidates and (b) survived after controlling for factors potentially correlated with disease threat, such as income and education. each of the findings reported above remained significant, even after controlling for gender, income, and education (see study : additional analyses in the supplemental material). study : disease threats and desired leadership characteristics study provided real-world evidence for the relationship between physical attractiveness and disease threat. of course, the correlational nature of the study limits our ability to affirm that disease threats causally shifted lead- ership preferences. in study , we experimentally manip- ulated disease threat and measured preferences for different leadership characteristics. additionally, we com- pared disease and self-protection threats to test whether disease threats uniquely affect preferences for physical attractiveness. method participants. one hundred twenty-three participants ( women, men; mean age = . years) were recruited through amazon’s mechanical turk and received a small amount of money in return for their participation. procedure. participants were told that they would read a story and that later their memory for it would be assessed. participants were randomly assigned to read one of three stories and were instructed to imagine them- selves in the situation described. the disease-threat story described a person volunteering at a geriatric ward who encountered a number of disgusting events—being sneezed on by a sickly person, seeing a person with an open wound, and finding a hair in his or her lunch. the self-protection story described a person, home alone dur- ing a stormy night, who realizes there is an intruder in his or her house. the control story described a person orga- nizing his or her office. to assess whether these manipu- lations created the desired psychological states, we queried participants about the emotions they felt while reading the story. as expected, participants in the dis- ease-threat condition reported feeling more disgust than did those in the self-protection and control conditions (ps < . ), whereas participants in the self-protection condition reported feeling more fear than did those in the disease-threat and control conditions (ps < . ). after the emotion questions, participants were asked to rate how important characteristics are in political lead- ers (e.g., power, trustworthiness; see study : materials in the supplemental material), using scales ranging from (not at all important) to (extremely important). the list of characteristics included “physical attractiveness.” results and discussion a one-way analysis of variance (anova) revealed a sig- nificant main effect of story on preferences for physical attractiveness, f( , ) = . , p = . , ηp = . . participants in the disease-threat condition (m = . ) rated physical attractiveness to be more important than did those in the self-protection (m = . , p = . ) and control (m = . , p = . ) conditions. there was no dif- ference between the self-protection and control condi- tions (p > . ). disease threats had no influence on ratings of the importance of of the remaining char- acteristics but did increase preferences for leaders who were “powerful” and “persistent” (ps < . ), compared with the control manipulation. the self-protection and control conditions were not significantly different from each other in ratings of any of the characteristics. we tested whether participants’ reported feelings of disgust after reading the disease-threat story mediated the relationship between story condition and preferences for physical attractiveness. following preacher and hayes ( ), we estimated the standard deviation of the indi- rect effect of story on preferences for physical attractive- ness for , bootstrapped samples. the indirect effect was estimated to lie between . and . with % confidence (β = . , se = . ). because zero was not included in the % confidence interval, this analysis demonstrates significant mediation. as predicted, the dis- ease-threat story engaged feelings of disgust, which, in turn, predicted preferences for physical attractiveness. study : disease threats and voting preferences in study , we found that people concerned about dis- ease, relative to other threats, explicitly reported physical attractiveness to be more important in a leader. in study , we sought to replicate and extend this finding by using a more subtle dependent measure—asking participants their willingness to vote for politicians who varied in physical attractiveness. method participants. two hundred ten american participants ( women, men; mean age = . years) were recruited through amazon’s mechanical turk. procedure. in study , we used the same manipulation used in study . after reading one of the three stories, at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ disease threats and leadership preferences participants viewed a series of photos of politicians and rated how likely they would be to vote for each one, using scales from (very unlikely) to (very likely). to ensure that our (american) participants would not recog- nize the politicians, we used photos of british politicians taken from http://sexymp.co.uk. this web site displays randomly paired official photos of elected members of the british parliament and allows the public to choose which member of each pair is more attractive; together, these choices create a ranking of the attractiveness of all members. we selected photos of the three most attractive and three least attractive politicians of each gender, as judged by visitors to the web site, resulting in a sample of photos. using an independent sample of u.s. uni- versity students, we confirmed that the attractive politi- cians were seen as more attractive than the unattractive politicians (p < . ). to mask the large attractiveness discrepancies among the photos, we combined them with photos from the same web site showing politi- cians who were ranked as average in attractiveness. results and discussion we conducted a (story: disease threat, self-protection, control) × (target gender: male, female) × (target attractiveness: attractive, unattractive) mixed anova. replicating previous results, there was a significant main effect of attractiveness on likelihood to vote for a candi- date, f( , ) = . , p < . , ηp = . . participants reported being more likely to vote for attractive politi- cians (m = . ) than unattractive politicians (m = . ). there was also a significant story × target attractiveness interaction, f( , ) = . , p = . , ηp = . (see fig. ). those in the disease-threat condition were more likely to vote for attractive politicians than were those in the self-protection (p = . ) or control (p = . ) condi- tions. there was no effect of condition on voting for unattractive politicians (ps > . ). story condition did not interact with target gender (p > . ), and there was no significant three-way interaction (p > . ). study : disease threat and job preferences in three studies, we found support for the hypothesis that disease threats increase preferences for physically attrac- tive leaders. in interpreting these findings, we proposed a special relationship between disease threats and leader- ship preferences. yet one might alternatively posit that the effects of disease threats are more general—that they lead people to prefer physically attractive others regard- less of their role in the group. indeed, the relationship between disease threats and leadership preferences is not entirely unique: in areas with elevated pathogen stress, people also prefer more physically attractive sex- ual partners (gangestad & buss, ). is there anything special, then, about the relationship between disease threats and preferences for physically attractive leaders? we agree that people concerned with disease may prefer group members, in general, to be healthier and more physically attractive. after all, human groups are highly interdependent, and people interact closely with others, which makes group members vulner- able to infection from others. we contend, however, that when a group faces disease threats, it is especially impor- tant for particular group members to be healthy. specifically, those concerned about disease should value health and physical attractiveness in the people with whom they interact the most (e.g., sexual partners) and on whom they are most dependent (e.g., leaders). building on previous research reporting that people are particularly dependent on group leaders (van vugt et al., ), we hypothesized that, all else being equal, during periods of disease threat, preferences for physically attractive group leaders will be stronger than preferences for physically attractive group members. to test this prediction, in study , we manipulated con- cerns about disease and examined whether people wanted physically attractive individuals to take on leadership roles or nonleadership roles. if the effects found in studies through were driven by a general preference for physi- cally attractive group members, participants concerned about disease should prefer physically attractive people . . . . . . . . . . . unattractive attractive w ill in gn es s to v ot e target physical attractiveness control disease threat self-protection story condition fig. . results from study : mean willingness to vote for candidates as a function of targets’ physical attractiveness and story condition. error bars indicate standard errors of the mean. at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ white et al. equally for leadership and nonleadership roles. however, if it is relatively more important for leaders to be physically attractive during periods of disease threat, participants should want physically attractive people to take on leader- ship roles. in study , we also extended the previous find- ings by using a different experimental manipulation of disease and assessing workplace, rather than political, leadership preferences. method participants. sixty-six participants ( women, men; mean age = . years) were recruited through amazon’s mechanical turk. procedure. participants were told they would take part in two separate studies. in the first study (actually our experimental manipulation), participants viewed a series of “advertising” images. half of the participants saw pic- tures selected to raise concerns about disease (e.g., bodily sores, a person sneezing); the other half saw pic- tures of office supplies (e.g., colorful markers, a stapler). this priming manipulation has been used in recent research examining the psychological consequences of disease threats (mortensen, becker, ackerman, neuberg, & kenrick, ). after viewing the photos, participants took part in what was ostensibly a second study on workplace dynamics (our dependent measure). they were asked to make a series of hiring decisions on the basis of minimal information—a photograph of a job candidate. participants were instructed to imagine that they worked for a large national corporation and that two positions were currently open in the company. the person filling one position would serve as the participant’s boss; the person filling the other position would serve as the par- ticipant’s coworker. because participants might have dif- ferent expectations for how much they would interact with people in these two positions, and because physical contact is likely related to disease concerns, we con- trolled for this potential confound. to do so, we told participants, “the new boss and coworker will work at a different office from you, but you will have meetings with the boss and coworker about once a week and corre- spond with them more frequently over e-mail.” participants were shown the same series of photos (three attractive and three unattractive people of each gender) used in study ; for each picture, they were asked, “would you rather this person be your coworker or your boss?” participants responded using -point scales from (definitely coworker) to (definitely boss). results and discussion we conducted a (picture manipulation: disease threat, control) × (target gender: male, female) × (target attractiveness: attractive, unattractive) mixed anova. there was a significant main effect of target attractive- ness, f( , ) = . , p < . , ηp = . . participants preferred the attractive job candidates (m = . ), relative to the unattractive job candidates (m = . ), for the boss position. there was also a picture manipulation × target attractiveness interaction, f( , ) = . , p < . , ηp = . (see fig. ). participants in the disease-threat condition preferred attractive job candidates for the boss position more strongly (m = . ) than did participants in the control condition (m = . ), f( , ) = . , p = . , ηp = . . in contrast, participants in the disease-threat condition preferred unattractive job candidates for the boss position less strongly (m = . ) than did partici- pants in the control condition (m = . ), f( , ) = . , p = . , ηp = . . the picture manipulation did not interact with target gender (p > . ), and there was no significant three-way interaction (p > . ). these findings support the prediction that, during periods of disease threat, preferences for physically attractive leaders are stronger than general preferences for physically attractive group members. general discussion in four studies, we documented the predicted relation- ship between disease threats and preferences for physi- cally attractive leaders. using real-world voting data in study , we revealed that in congressional districts with a . . . . . . . unattractive attractive sc or e target physical attractiveness control disease threat picture condition fig. . results from study : mean employment-preference scores as a function of target physical attractiveness and picture condition. lower scores indicate preferences for the target to be a coworker; higher scores indicate preferences for the target to be a boss. error bars indi- cate standard errors of the mean. at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ disease threats and leadership preferences high level of disease threat, physically attractive candi- dates received a greater percentage of the vote and were more likely to be elected to the u.s. congress. there was no such relationship in congressional districts with a low level of disease threat. two experiments showed that a disease-threat manipulation, relative to self-protection and control manipulations, increased explicit preferences for physically attractive leaders (study ) and willingness to vote for physically attractive politicians (study ). finally, in study , we demonstrated that people con- cerned about disease want physically attractive people to take on leadership roles rather than nonleadership roles. in this research, we adopted a functional-evolutionary perspective to make predictions about the relationship between disease threats and preferences for physically attractive leaders. to our knowledge, no other theoretical perspective has generated similar hypotheses. moreover, we note that predictions couched in terms of more proxi- mal mechanisms do not necessarily constitute “alterna- tives.” instead, it may be through these mechanisms that more distal processes have their effects. nevertheless, it is possible that functional, nonevolutionary approaches may also account for these findings. because this research is relatively novel, more work is needed to better under- stand the origins of these effects. as a whole, this research expands understanding of the behavioral immune system in several ways. although disease avoidance is an individual concern, these findings highlight the role that disease-avoidance mecha- nisms can play in broader intragroup processes— leadership preferences and voting behavior. further, these results contribute to a growing body of literature distinguishing between psychological reactions to dis- ease threats and self-protection threats (neuberg, kenrick, & schaller, ). past research has shown that self-pro- tection threats can increase preferences for masculine, dominant, or charismatic leaders; these findings show that disease threats increase preferences for physically attractive leaders. finally, this work demonstrates the functional specificity of preferences for physical attrac- tiveness. even though it is possible that people con- cerned about disease may prefer everyone to be healthier and more physically attractive, these results show that it may be particularly important for certain group members to be physically attractive. people facing disease threats seem to value health and physical attractiveness in those with whom they interact most intimately (e.g., sexual partners) and in those on whom they are most depen- dent (e.g., leaders). as a whole, these findings show that leadership prefer- ences, like a wide range of other phenomena (e.g., stigma, personality inclinations, mate preferences, and confor- mity), can be contingent on disease-avoidance mecha- nisms. in doing so, they also highlight the advantage of considering leadership preferences from a functional evo- lutionary perspective. previous work has led to the broad conclusion that preferences for attractive leaders rest on simple inferences that attractive people possess desirable traits. using functional reasoning in the current investiga- tion, we were able to generate several novel hypotheses and findings regarding leadership preferences, thereby enhancing the understanding of when and why beauty wins out at the ballot box. author contributions all authors developed the study concept and contributed to the study design. testing, data collection, and data analysis were performed by a. e. white. a. e. white drafted the article, and d. t. kenrick and s. l. neuberg provided critical revisions. all authors approved the final version of the article for submission. declaration of conflicting interests the authors declared that they had no conflicts of interest with respect to their authorship or the publication of this article. supplemental material additional supporting information may be found at http://pss .sagepub.com/content/by/supplemental-data references ackerman, j. m., becker, d. v., mortensen, c. r., sasaki, t., neuberg, s. l., & kenrick, d. t. 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( ). origins of major human infectious diseases. nature, , – . at university of missouri-columbia on january , pss.sagepub.comdownloaded from http://pss.sagepub.com/ http://pss.sagepub.com/ laudato si': the beauty of pope francis' vision s.a.p.i.en.s surveys and perspectives integrating environment and society . | vol. / n° laudato si': the beauty of pope francis' vision andrea tilche and antonello nociti nicolas renard (ed.) electronic version url: http://journals.openedition.org/sapiens/ issn: - publisher institut veolia electronic reference andrea tilche and antonello nociti, « laudato si': the beauty of pope francis' vision », s.a.p.i.en.s [online], . | , online since november , connection on december . url : http:// journals.openedition.org/sapiens/ licence creative commons http://journals.openedition.org http://journals.openedition.org http://journals.openedition.org/sapiens/ http://sapiens.revues.org/ published: november edited by: nicolas renard © author(s) . this article is distributed under the creative commons attribution . license. laudato si’: the beauty of pope francis’ vision. authors: andrea tilche and antonello nociti andrea tilche, scientist and science manager, after years working as a scientist career in the field of water technologies, moved to the european commission in brussels where he is currently head of the unit “cli- mate action and earth observation” in the directorate-general for research and innovation (andrea.tilche@ ec.europa.eu) *. antonello nociti, writer and philosopher, was one of the leaders of the milanese student movement in the years around . a philosophy graduate, he is author of several novels and essays, among which “guarire dall’odio: come costruire una pace multirazziale” ( , il mulino), on the south african experience of the truth and reconciliation commission. *disclaimer: this document does not represent the point of view of the european commission. the interpretations and opinions contained in it are solely those of the author. the encyclical letter of pope francis, “laudato si’”, addresses for the first time in the church’s history the subject of the protection of the environment, “the care of our common home”. this rich and complex document analyses the causes of today’s ecological challenges, acknowledging the scientific consensus but adding an original analysis of the social, cultural, ethical and spiritual dimensions that are associated with the degradation of the environment. the pope’s vision is that the ecological crisis is ultimately linked to a crisis of values, a spiritual void that permeates today’s technocratic society. in the authors’ analysis, what makes this document particularly innovative is the pope’s appeal to action that, acknowledging the urgency and the immensity of the challenge we face, sees also its beauty, being a unique occasion for humankind to show what it is capable of doing, and that is capable of taking responsibility. this positive narrative has the potential to mobilise people and governments towards a joint action that cannot however be limited to techno- logical fixes, but should be broadened to consider new development models capable of addressing the deep roots of this crisis. keywords: encyclical, pope francis, climate change, ecological crisis, ethics, responsibility a bs tr ac t ’’ comments s . a . p . i . e n . s vo lu m e is su e tilche and nociti | p andrea tilche and antonello nociti laudato si’: the beauty of pope francis’ vision. table of contents . introduction . the encyclical’s preamble . the body of the encyclical . for an assumption of responsibilities . some concluding considerations . references “in the history of the human spirit i distin- guish between epochs of habitation and epochs of homelessness. in the former, man lives in the world as in a house, as in a home. in the latter, man lives in the world as in an open field and at times does not even have four pegs with which to set up a tent.” — martin buber, “between man and man”, . . introduction the encyclical letter “laudato si’: on care for our common home” is addressed —probably for the first time in history, as edenhofer et al. ( ) remind us — not only to christians or to “all people of good will”, but to “every person living on this planet” [§ ] . this encyclical letter is the most innovative among the many proposals put forward by world leaders in recent years on the road that should lead us to take common decisions on climate change and on the road that recently led the united nations to agree on the post sustainable development goals. pope francis has raised the level of the debate, forcing sec- ular leaders to do the same. the encyclical struck a chord across the denominations , and policy-makers and civil soci- ety welcomed it. the pope’s message, coming from the highest authority of a religion counting more than one billion followers, has the potential to generate a tremendous impact worldwide. his message, also thanks to pope francis’ moral standing and communication capacities, is heard by many more people, believers of all religions and non-believers. what may attract all readers is that pope francis has with this document shown leadership, and the ability to draw a new and very powerful narrative. he has affirmed the beauty of the challenge in front of us, which gives humanity a unique occasion of showing what it is capable of doing. because http://w .vatican.va/content/francesco/en/encyclicals/documents/papa- francesco_ _enciclica-laudato-si.html the numbers in square brackets refer to the numbered paragraphs of the encyclical letter. see in particular the islamic declaration on global climate change that was released in august (http://islamicclimatedeclaration.org/islamic- declaration-on-global-climate-change/ (archived by webcite® at http:// www.webcitation.org/ cjfuzwnl)), mirroring the content of the encyclical. humankind has developed outstanding capabilities in science and technology — as well as in societal and institutional settings — it can also prove itself capable of using its huge capacities for the greater good and healing the planet, acting as a “co-operator(s) of god in the work of creation” [§ ]. this approach reverses the current narratives, such as the catastrophist one of several environmentalist movements, which may lead to surrender, or the fear of global recession preached by the fossil fuel lobbies, or the blind faith in technology as being capable of solving every problem. pope francis recognises that it presents huge economic and ecological challenges, but considers that it is good that mankind can be challenged at such a high level that it has to show its best. this reversal of the discourse is capable of giving enthusiasm and encouragement to people. we are no longer discussing whether and to what extent climate change or resource depletion is due to human activities. this has been thoroughly assessed by science. we have to decarbonise the planet and we have to do it rapidly. we have to stop the destruction of the planet’s natural capital. let us do it, says pope francis, with the joy of knowing that it will be a beautiful collective effort that beyond saving our common home will make all of us become better human beings. this is because the ecological challenge is also a social one and a challenge of values, and the way out requires an engagement of responsibilities that will lead to a deep change not only in our relationship with the natural environment, but also in our social relationships, in our solidarity towards the less well off, and ultimately in the awareness of the meaning of our life. . the encyclical’s preamble it is here that pope francis gives us the deep roots of his thought: his recalling of saint francis’ view of beauty and fraternity with all creatures, his profound spiritualism that sees the social, but more fundamentally the ethical and spiritual roots of environmental problems and calls for a spiritual change of humankind in order to solve them, and his openness to listening to and learning from science and to entering into a dialogue with all, starting with a reflection that we all have been part of the problem and shall all be part of the solution. the key to pope francis’ encyclical rests in his plea to “acknowledge the appeal [in the spanish text, which is probably the original, it reads “hermosura”, beauty], immensity and urgency of the challenge we face”. as a christian philosopher of orthodox origin, nikolai berdyaev, said, and the pope recalls more than once in the text, “…our mission is to be co-operators with god in his continuing creation of the world” (berdyaev, ). that is, it is good that humankind can test its capability of “co-operating with god in creation”, and can show how it can respond to the huge responsibility of having developed the capacity to modify tilche and nociti | p s . a . p . i . e n . s andrea tilche and antonello nociti laudato si’: the beauty of pope francis’ vision. the world. humankind has in fact developed huge capabilities, and therefore has huge responsibilities. this sets the framework in which the long encyclical is written. the following is an analysis of its discourse. . the body of the encyclical the first chapter of the encyclical draws a picture of the prob- lem, namely what is happening to “our common home”. the changes affecting humanity and the planet are accelerating. after a period of “irrational confidence in progress and human abilities” [§ ] we have to ask ourselves whether this is the right way to go. the “throwaway culture” [§ ] is shown as opposite to how nature works in sustainable cycles; this label does not refer only to material goods, but to human beings as well, which are discarded as waste when they are no longer useful to support the needs of the dominating technocratic paradigm . the letter then offers the reader a simple and well-drawn depiction of climate change, recognising that it “represents one of the principal challenges facing humanity in our day” [§ ] and that it mainly affects developing countries and the poor and more vulnerable populations, which are more dependent on natural capital and ecosystem services, and have less capacity to adapt. the encyclical then presents, in correct but non-scientific language, other essential elements of the environmental crisis, such as the pressure on water resources or the loss of biodiversity. the great novelty of this framing of the problem is its endorsement of the scientific consensus. the church has made a long journey in its relationship with science, and it is not just from today that it recognises science and technology as “wonderful products of a god-given human creativity” [§ ]. but the breadth of the use of arguments from science is a peculiar character of this encyclical. the second part of the first chapter addresses the human and social dimension of the ecological crisis. considering that the human and the natural environment deteriorate together, it turns the discussion to the poor, the most vulnerable, and the excluded, as those who suffer first and foremost from the effects of environmental degradation. it recognises that “a true ecological approach always becomes a social approach” and therefore that issues of justice have to be integrated in environmental debates, “so as to hear both the cry of the earth and the cry of the poor” [§ ]. the second chapter addresses issues in relation to the convictions of believers. why? the letter says that science and religion have the potential to enter into a profitable dialogue that may be mutually enriching, because the solution does not this theme evokes the “human waste” of zygmunt bauman in “wasted lives: modernity and its outcomes” ( ). only lie in the realm of science, but also relies on the buy-in of all of us, with our own religious values. what is however the coherence among the biblical texts concerning the relationship between god, humankind and nature? in genesis god grants humankind “dominion” over the earth, while it also invites us to cultivate and care, “till and keep” [§ ], the garden of the world. if the first statement can be interpreted as the freedom to exploit, the second implies a relation of reciprocal responsibility between man and nature. the bible contains similar contrasts, and does not have to be read literally. it must also be recognised that the reading of some parts of the bible may lead to the view that our living world is bad because man ruined it through sin. this view is somewhat opposed to saint francis’ view of the brotherhood of humankind with all creatures and the planet. his famous hymn “laudato si” (be praised my lord), which gives the encyclical letter its name, is reported in its entirety in the text, showing the importance that pope francis attributes to the franciscan message in proposing his vision of the world. saint francis wrote his hymn in , a quite different time with respect to today. humanity in fact has entered into a new era of technological development that is progressively overcoming our material limitations. technoscience, when well directed, is not only capable of producing useful tools for improving the quality of human life, but is also capable of producing “beauty” [§ ], says the pope. however, it has brought humankind to a crossroads. in fact, modern technological capacity gives humankind a tremendous power, but this has not been accompanied by “a development in human responsibility, values and conscience” [§ ]. this lack in the ethical and spiritual dimension may lead to a lack of limitations to human acts. from this, it is easy to arrive at the idea of an infinite or unlimited growth, supported by the “false notion” [§ ] that resources are unlimited. the technocratic paradigm “has become so dominant that it would be difficult to do without its resources and even more difficult to utilise them without being dominated by their internal logic” [§ ]. and this paradigm “also tends to dominate economic and political life” [§ ], expressing profit as the main logic behind technological development. we are faced with the urgency “to move forward in a bold cultural revolution” [§ ], but for this we need to start from analysing what man is. a key reflection of the encyclical letter is expressed in the statement that “there can be no ecology without an adequate anthropology”. the human person cannot be seen just as one living organism among others. if we wish human beings to en- gage in taking care of the planet, we have to recognise and value “their unique capacities of knowledge, will, freedom and responsibility” [§ ]. tilche and nociti | p andrea tilche and antonello nociti laudato si’: the beauty of pope francis’ vision. the narration then evolves considering that there are not “two separate crises, one environmental and the other social, but rather one complex crisis which is both environmental and social” [§ ]. the “integral ecology”, which pope francis proposes, requires the integration of the economic, social and cultural dimensions. an integral human ecology, says the letter, cannot be separated by the notion of the “common good”, “a central and unifying principle of social ethics” [§ ]. this notion opens deep reflections on justice, which go beyond the relationships of today, implicitly including the “rights” of future generations, with the qualification that intergenerational justice should be accompanied by intra-generational justice. but which kind of world do we want to leave to future generations? we leave the words of the pope unchanged, because they are touching in their comprehensiveness: “it is no longer enough, then, simply to state that we should be concerned for future generations. we need to see that what is at stake is our own dignity. leaving an inhabitable planet to future generations is, first and foremost, up to us. the issue is one which dramatically affects us, for it has to do with the ultimate meaning of our earthly sojourn” [§ ]. recently john schellnhuber said that the “implosion” of the fossil fuel society will result from d’s: disasters, discover- ies, but more and foremost — agreeing with the pope — it will be a matter of decency, because humankind cannot show it- self to be incapable of finding solutions for its own survival. when finally proposing solutions, the letter makes a plea for a hierarchical role of politics over the economy, because, as jeffrey sachs commented, “he’s calling on us to come back to the idea that the economy is to serve human well-being, not human well-being serving the economy” . the solution cannot lie just in the application of technological fixes: in order to build a sustainable future which does not repeat the errors of today, a deep change in the current development model is requested. humanity needs to change. consumerism is the reflection of the technocratic paradigm. “we have too many means and only few insubstantial ends” [§ ], says the letter, and continues: “the emptier a person’s heart is, the more he or she needs things to buy, own and consume” [§ ]. but human beings are capable of doing more and rejecting such a poor paradigm. john schellnhuber, director-general of the potsdam institute for climate impact research, adviser of the german chancellor angela merkel on climate change, member of the pontifical academy, participated in the preparatory work of the laudato si’ encyclical letter; the reference made in the text is the author’s synthesis of the position expressed by john schellnhuber at a discussion panel at the paris conference “our common future under climate change”, july . see the comment to the visit of the pope to the us by jeffrey sachs— economist, un adviser and director of the earth institute of columbia university—interviewed by chris mooney in: https://www.washingtonpost. com/local/social-issues/how-pope-franciss-united-nations-could-help-the- world-fix-the-climate-change-problem/ / / /e a - d- e - b e- aacba _story.html the core and conclusive element of the encyclical rests in the suggestions of “ecological spirituality” [§ ] that are offered, which build on the conviction that beyond ideas, we also need a mystical move, “an interior impulse” which motivates our individual and communal action. the ecological crisis calls for a deep interior conversion, which implies “gratitude and gratuitousness” [§ ], sobriety and humility. pope francis proposes love as the overarching paradigm, a “civilisation of love” [§ ], making it the “constant and highest norm of all activity”. this will encourage a “culture of care” to permeate all society, an assumption of responsibilities to take care of the planet and of the quality of life of all, and in particular to take care of the poorest members of society. . for an assumption of responsibilities what will trigger this assumption of responsibilities? the development of a new ethics is necessary, which implicitly requires the recognition of our planet as a common good and that the unique scientific and technological capacities of man, together with his capacities of will and freedom, have impacted on the earth with consequences that extend into the future, but can also be used to heal the planet. we cannot leave an uninhabitable planet to the future generations: it is fundamentally a matter of dignity for us, who know and who have the means to act, a matter of minimal decency that we cannot fail to respect. as dietrich bonhoeffer ( ) said, it is time for the adulthood of humankind; it is time for taking responsibilities. the ethical proposal of pope francis approximates the responsibility ethics of jonas ( ), even if they are built on rather different assumptions. both consider that humankind has huge capabilities and responsibilities. both trust man to be capable of using this capacity and responsibility for the greater good. jonas thinks that ethical wisdom is a necessary value to contrast the blind faith in technology. pope francis says something very similar when he calls humanity to search for values and for an inner conversion. one critical remark advanced in some of the recently pub- lished commentaries on the encyclical is that the powerful and pervasive technocratic paradigm cannot be defeated just through a cultural change. the argument has only limited va- lidity. first, the encyclical, with its power to reach millions of people at every level of decision-making capacity, may have both a direct and an indirect influence on policy-making. sec- ondly, changes in history have always had their roots in ideas, and in the digital era ideas circulate faster and are a very pow- erful means of transforming society. thirdly, individual be- haviour increasingly has a systemic impact, which is already evident in the transformation of consumers into ‘prosumers’ . other commentaries have looked at sectoral aspects of the neologism from the fusion of “producers” (of energy) and “consumers”, relating to the diffusion of self-produced photovoltaic energy that, when in excess, may be sold to the grid. tilche and nociti | p s . a . p . i . e n . s andrea tilche and antonello nociti laudato si’: the beauty of pope francis’ vision. so why shouldn’t the same be true in the face of the risks of survival of the planet? the importance of the relationship of this encyclical to sci- ence has already been underlined. the critical words aimed at those who manipulate information [§ and elsewhere] show that the church does not question the scientific consensus. the high consideration of science, combined with the refer- ence to a wide number of thinkers of other religions and even to philosophers, are signs that what is proposed here is a new humanism, in which all creative capacities of humankind, in- cluding religions and spirituality, can contribute to the “bold cultural revolution” that is proposed, which can provide the arguments and the moral push that may help women and men living on this planet to become actors of change. a change that may help humanity to “feel again at home” — as buber ( ) would have said, in his common home. there is a spiritual and ethical void, an absence of scope in today’s technocratic society that needs to be filled, and this encyclical contributes to fill this void. references berdyaev, n. ( ; ). the meaning of the creative act. harper & brothers. bonhoeffer, d. ( ). letters and papers from prison. scm press. buber, m. ( ). between man and man. routledge & kegan paul. edenhofer, o., c. flachsland & b. knopf ( ). science and religion in dialogue over the global commons. nature climate change : – . jonas, h. ( ). das prinzip verantworung [the imperative of responsibility]. first english edition , university of chica- go press. “in the history of the human spirit i distinguish between epochs of habitation and epochs of homelessness. in the former, man lives in the world as in a house, as in a home. in the latter, man lives in the world as in an open field and at times does not even have four pegs with which to set up a tent.” — martin buber, “between man and man”, . encyclical, and in particular its sometimes explicit economic and political anti-capitalistic discourse — which is not new in the social doctrine of the church — its opposition to (blind) market values and its view of finance as a perverse force. it cannot be denied that financial markets work for maximising profits, and are mostly unethical. however, they are also precursors of change. there are plenty of financial actors today that are strongly engaged in orienting the choices of corporations towards actions that guarantee the longterm security of their assets, and are very concerned by the risks of dangerous climate change or of the depletion of natural resources. those asset managers are acting in the right direction, and it is imperative to create an alliance with them. . some concluding considerations the encyclical “laudato si’” is a complex document, probably resulting from the writing of several different authors , and the presence of some contradictory statements, the raising of issues of lower relevance with respect to the main subject may well be the result of compromises reached between different orientations. however, we do not think that sectoral aspects can be extracted and seen in isolation. what we have proposed here is the reading of what we see as a coherent whole: the pope’s view that the ecological crisis is just one of the symp- toms of the throwaway culture and of the technocratic par- adigm which looks to the continuation of its internal logic. his analysis leads to the conclusion that this socio-ecological crisis can only be steadily defeated if its deep roots are ad- dressed, namely the desert of values that permeates modern societies. the encyclical offers some replies to this. for believers, it says that it is in the recognition of the presence of a creator to whom everything belongs that we may better respond to and care for our common home. however, the paradigm of love and brotherhood that pope francis proposes can be shared by many more than just believers. it also makes sense in a secular context. it means addressing, together with the care for the environment, fundamental issues of social justice and of north-south equity. many economists today, including those from liberal schools of thought, are fully aware that the dramatic increase of inequalities needs to be reversed. it is not sustainable even within capitalism, and it is a sign that markets have several failures and require corrective actions that can only be offered by policy-making. even the proposal of global governance based on more trust among people, communities and nations is not utopia. it is certainly a very hard and difficult task. gandhi and mandela have shown such trust to be possible, see, for example, the interesting article of william nordhaus. the pope & the market. new york review of books. url:http://www.nybooks.com/articles/ archives/ /oct/ /pope-and-market/. (archived by webcite® at http:// www.webcitation.org/ cjbx pk) see the declaration of pope francis mentioned at the press event for the presentation of the encyclical at: https://press.vatican.va/content/ salastampa/fr/bollettino/pubblico/ / / / / .html (archived by webcite® at http://www.webcitation.org/ cjmtzesn) pii: s - ( ) - landscape and urban planning ( ) – the impact of agroforestry networks on scenic beauty estimation the role of a landscape ecological network on a socio-cultural process daniel franco a,∗, davide franco b, ilda mannino a, gabriele zanetto b a department of environmental science, ca’foscari university of venice, dorsoduro , venice, italy b departamento de engenharia sanitária e ambiental, universidade federal de santa catarina, florianopólis, brazil accepted may abstract the reintroduction of agroforestry networks (via a gis-supported design procedure) is one of a number of strategies that some authorities of the lagoon of venice drainage basin (in italy) are planning to use in order to control lagoon pollution and to achieve landscape amelioration. while attention is paid to the conservation implications and environmental effects of an ecological network, socio-cultural impacts are not generally given the same consideration. the aims of this paper were ( ) to assess the impacts of agroforestry network planning outputs on the perception of landscape in terms of scenic beauty (sb) estimation, ( ) to analyze the influence of socio-economic variables on the agroforestry role in sb, ( ) to analyze the relationships between sb and landscape variables as measured on the local and landscape scales, and ( ) to assess the strength of an expert rating sb empirical procedure utilized in the gis system. the outcomes of the gis planning procedure application were found to have a positive impact on the perceptive evaluation of landscape, but landscape sites preference did not appear to be significantly different between socio-economic groups: in all cases, sites with an optimized agroforestry network were preferred to the same sites without. a strong explanatory relationship was found to exist between citizens’ scenic beauty estimation (sbe) and the landscape metrics. the representative empirical procedure gave sound qualitative results for this kind of landscape, but can be efficiently substituted by the regression model tested at the “local” scale. at the “landscape” scale it appears that ( ) the explanatory power of the landscape pattern metrics selected for the gis procedure is high, even for the mean “social” sbe, ( ) the main explanatory power among network metrics is expressed by connectivity and circuitry, and ( ) it is reasonable to expect that the impact of an agroforestry network on citizens’ sbe could be predicted with the empirical models that were tested. © elsevier science b.v. all rights reserved. keywords: landscape; gis; agroforestry; networks; scenic beauty (sb); aesthetics; spatial pattern analyses; landscape preferences ∗ corresponding author. present address: castello, - venice, italy. tel.: + - - ; fax: + - - . e-mail address: daniel.franco@iol.it (d. franco). . introduction countries within and outside the european union are promoting agroforestry policies to preserve rural landscapes (eu rule / ), and some authorities of the lagoon of venice drainage basin (in italy) are aiming to control lagoon pollution by developing - / /$ . © elsevier science b.v. all rights reserved. pii: s - ( ) - d. franco et al. / landscape and urban planning ( ) – strategies that include the planning of agroforestry networks (progetto siepi©) reintroduced by means of a design procedure supported by a geographic information system (gis) (planland®©; franco, ). great attention is given to the conservation and envi- ronmental implications of an ecological network (e.g. hudson, ; forman, ), but socio-cultural im- pacts (burel and baudry, ) are not generally given the same level of consideration. but we need to con- sider the values that individuals and society place on the non-market aspects of landscape, like “beauty”, in order to maximize the efficiency of the resource allo- cation in landscape management. in dealing with agroforestry networks, we can con- sider the impact of socio-cultural or socio-economic processes on the landscape in terms of landscape functions connected to landscape structures in a land- scape ecology perspective (see burel and baudry, ; forman, , for a wide discussion about this concept). there are two main reasons for this. the first reason is that human culture, even from an aesthetic and mythological perspective, influences landscape changes and these changes, conversely, in- fluence culture (arler, ; soriani et al., ; turco and zanetto, ). these relationships lead to some consequences expressed by two principles (nassauer, ): ( ) human perception, cognition and evalua- tion directly influence and are influenced by landscape structures and functions; ( ) cultural processes influ- ence both built and “natural” landscapes. landscape functions are defined as fluxes of energy and matter, and perception, cognition and valuation of landscape can influence the transformation of land- scape structure, for this reason this process can modify the fluxes of energy and matter in a landscape. going on we believe that if we extend the “natural landscape” idea from a cultural perspective (see shama, , for a wide discussion about this topic) to the landscape ecology perspective of “landscape” (sensu. forman and godron, ) we can treat the cultural process linked to the human perception as an ecological func- tion: there is no difference, from the ecological point of view, between humans modifying a dense under- story because it does not have a perceptive cultural value (nassauer, ), or beavers modifying the hy- draulic asset of entire watersheds. the second reason is that the several theories pro- duced on this topic (mostly “information processing”, kaplan and kaplan, ; “biological”, appleton, ; bourassa, ) have some foundations in com- mon: ( ) there are some elements—such enclosures or distant vistas (open/closed spaces composition), fresh and clean water (e.g. gregory and davis, ), and canopy features (e.g. lamb and purcell, )—which strongly influence the appreciation/non-appreciation of a landscape, with an importance that varies ac- cording to the observer’s life history, his or her own elaboration capacity and information availability (e.g. brunson and reiter, ), and the cultural heritage of his or her social group (e.g. purcel, ); ( ) these theories (biological, information processing, and the correlated ones) support the validity of the links between the preference ⇔ the human behavior ⇔ the landscape change (i.e. the two principles de- fined above) and are compatible with the analytical and descriptive patch-corridor-matrix model utilized in landscape ecology (bell, , ; nassauer, ), if visually considered. if these socio-cultural processes can be analyzed with a landscape ecology approach, then—to correctly support an agroforestry network design—the planners need to assess how these landscape structures affect the aesthetics of the landscape. we need, therefore, to verify if and how the results of agroforestry network planning has an influence on “social” landscape appre- ciation in order to understand if it would be possible to obtain optimum trade-off scenarios from the ecologi- cal, agronomic and aesthetic perspectives. this could be a democratic means of efficiently taking this social process into account in a landscape planning approach (arler, ). if there is this influence, the procedure that land- scape planners should utilize would have to be simple, rapid (automatic) and reliable for large areas (bishop and hulse, ). the rapidity of the evaluation pro- cedure it is an economic constrain, mostly in the case of large evaluated areas, that is to say, when the pro- cedure has to be used many times. two types of approaches for estimating landscape appreciation are described in the literature: the percep- tion based approach and the expert based approach (daniel, ). the first approach is based on regression models be- tween scenic beauty (sb) estimations and explanatory d. franco et al. / landscape and urban planning ( ) – landscape variables (representative models), and sec- ond approach is based on empirical weighting criteria of landscape appreciation descriptors to be valued by experts (expert ratings models). neither of these ap- proaches, however, have the required characteristics stated above. dealing with representative models and following the analyses of hunziker and kienast ( ) we de- cided to compare sb (treated as a dependent variable, daniel and boster, ) with some landscape descrip- tors treated as independent variables. the use of sb as a statistical variable permitted us to develop statistical comparisons between each real (not planned) and each simulated (planned) site, and to have a first estimate of whether there is a role of the agroforestry network planning outputs in the sb values of the whole sample, that is, the mean “social” landscape beauty valuation. doing that and, more, to develop the regres- sion models, we had to determine how the struc- tural composition of the society sample influenced the sample (“the society”) scenic beauty estimation (sbe): the more variance of sb can be explained by socio-economic variables, the less the sb used for comparison represents the whole community sbe and/or the less reliable the regression model based on landscape-variables are. after that, landscape (independent) variables were measured at two different scales of perception, to eval- uate the influence of scale on the landscape structure vs. function (e.g. agroforestry network per sb percep- tion) relationship. at the “local” scale (the human-natural perception scale, at the ground level) we did not use variables that were “objectively measurable” in the terrain (e.g. the basal area, the dominant height, . . . ) because of the intrinsic difficulty of eliminating the subjectivity of the expert view with regard to the variables chosen, and because of the possibility that there may not be a relationship between the measurable characteristic and the informative contents of the perceived image. we preferred to examine this content directly, by means of the abundance ratio of the perceived landscape ele- ments (like buildings, hedgerow, fields, . . . ), together with some indices of their composition (see section for explanations). while this is less correct statisti- cally, it is more directly meaningful to estimate the ac- tually perceived role of the agroforestry network role in citizens’ landscape beauty appreciation, and more directly comparable to the perceived composition of the patches (like fields) and corridors (like hedgerow). at the “landscape” scale (the non-human-natural perception scale, from aerial photographs), we used “measured formal landscape criteria”, (hunziker and kienast, ) in this case landscape pattern indices, because agricultural changes connected to agroforestry implementations (see franco, , for review) affect the formal content of landscape (that is, the pattern). regarding the experts ratings models, they try to synthesize the visual quality of a site by ( ) an estimate of visual aspects of a picture by an expert, who assigns scores to some landscape descriptors of perceptive appreciation and refuse (selected from the literature or by means of specific researches), and ( ) a succes- sive weighted aggregation of the scores (e.g. brouwer, ; scrinzi et al., ). the experts ratings empiri- cal procedure that was utilized in planland®© (vi- sual quality condition (vqc) franco, ) operates in a similar way (as detailed under section ). this procedure, however, is very time-consuming for large areas, is not theoretically as robust as representative models, and needs at least a qualitative test of its reli- ability. this study belongs within a wider framework of research evaluating the agroforestry network im- pact on the social, cultural and economic processes in the venetian landscape. the other research aims were: • to evaluate social awareness of non-point source pollution and of the agroforestry network roles (mannino et al., ); • to estimate the contingent value of the agroforestry network, and to evaluate the correlation of the ex- isting policy (with its benefits for agroforestry plan- tation) with farmers’ expectations (franco et al., ). in this paper, we are reporting on the results of our research into the impact of agroforestry networks on sb valuation of landscapes, and addressing the plan- ning consequences of the impact that was found. our aims in this paper are . to analyze the influence of socio-economic vari- ables and of the effect of agroforestry on the land- scape sbe; . to assess the impact of landscape amelioration planning output (which employs an optimized d. franco et al. / landscape and urban planning ( ) – agroforestry network analysis and gis design procedure) on the sb of the landscape; . to analyze the relationships between sb and land- scape descriptors at the “local” (ground level) and at the “landscape” (aerial photographs) scale, in order to gain empirical knowledge about the in- fluence of agroforestry planning on sb, and to find out if sb is sensitive to some measurable characteristics of landscape (that are sensitive to agroforestry network implementation); . firstly to assess the strength of the sb evaluation approach utilized in the gis planland®© (an expert ratings empirical procedure, vqc; franco, ) by means of a qualitative comparison, in each of the pictures examined, between the “social” (statistical) sb values and the experts’ beauty- weighted index. secondly to compare in the same experimental system (the analyzed landscape) two of the most widespread sbe approaches used in the planning assessment and linked to two different ways of thinking (see for discussion daniel, ). . methods . . respondents a stratified random sample of farmers, venetian (la- goon) citizens and venetian drainage basin citizens (non-lagoon citizen), was chosen from telephone list- ings. the sample consisted of families and uni- versity students (architecture course of urbanism and planning; environmental science). the number of re- spondents was . the “socio-economic variables” (categories) and their representation in the sample are reported further. socio-economic variables classes sex males %, females % age : – years %; : – years %; : – years %; : > years % educational status : primary school %; : high school %; : graduate % job : farmers %; : students %; : employees and professionals %; : retired workers and housewives %; : other (unemployed) % family : – persons %; : persons %; : persons %; : > persons % income (in this case, only % of respondents answered) : – . , %; : . – . , %; : > . , % residence location : venice and islands %; : mestre and suburbs %; : inland-farmlands % surveys were mailed and every person per family was contacted afterwards by phone to clarify the sci- entific aims of the research, or directly given to the university students. . . procedure the sbe was carried out using images ( cm × cm, taken in the county rural landscape) which were rated using a point scale. the number of images, the number of respondents and the kind of represen- tation to be used were based on literature review (e.g. stamps, ). a scoring method on photographs has been used, because it gives the same results as com- parison methods and it is easier to use in this type of survey (hunziker and kienast, ). six of the images were real, taken with a mm lens and asa slide. all of the images were taken in the same season (october ) to reduce uncertainty in the interpretation of results (fig. ). all of the images were geocoded in the gis that was utilized for the agroforestry network planning (fig. ). six of the images were obtained by modifying the slides by simulating as exactly as possible the planned agroforestry systems as thy would appear in the th year after plantation. the perspective and dimension of the plantation were obtained first by a simulation soft- ware (acurender®©, planland®©) and then reproduced by photo-composition. images were well mixed and printed on different pages to prevent peo- ple from recognizing the same sites with and without planting (fig. ). the images were tested by a group of people (four professional designers and six uni- versity students) before mailing: nobody recognized d . f ra n co et a l./l a n d sca p e a n d u rb a n p la n n in g ( ) – fig. . a simplified representation of the studied area and of the six analyzed visual fields. d. franco et al. / landscape and urban planning ( ) – fig. . results of the six sites really photographed and the same six sites after the agro-forestation planning simulation, as presented to the respondents (from the first to last page). here are reported, too, the sites’ codes: the simulated images are indicated with an “a” after the arabic code of the real sites images. d. franco et al. / landscape and urban planning ( ) – the same sites with and without the planned agro- forestry systems. to reduce the subjectivity of ratings for sb scaling, an origin-adjusted rating scaling procedure was chosen due to its simplicity and robustness when compared to other more complex procedures, given the statistical representativeness of the sample. the i value given by the j respondent was substitute by the difference between the mean value of respondent j and the value of i. other scaling procedures were tested (e.g. full z score), but, as expected (stamps, ), no differences were detected. statistical comparisons have been made with a parametric anova. parametric assumptions were es- timated with visual and numerical methods and non- parametric kruskal–wallis anova was used when violation of the parametric assumption were detected, given that scoring methods rely on an ordinal scale. when no differences were detected in parametric and non parametric anova results, the duncan test was utilized to detect homogeneous groups and/or significant differences. correlation was calculated with spearman coefficients and with pearson product moments, to detect differences. explorative multiple linear regression models (stan- dard and forward stepwise) were calculated for the comprehension of the functional relation of the con- sidered variables. ridge regression was utilized to re- duce the problems due to variables collinearity. intrinsic not linear models (piecewise linear re- gression models) were tested to value the strength of possible design tools. both correlation and regres- sion models were calculated with mean sb values weighted by the sb standard error. because of a mailing error, the sites and a (fig. ) lacked in judgements and for this reason were rejected in some sites versus socio-economic variables interac- tion analyses (when the number of observations were statistically not significant). commercial software packages were applied (statistica©, excell©, systat©, statgra- phics©, photoshop©). . . landscape descriptors sbe results were related to landscape variables, of both “local” (human-natural perception scale) and “landscape” (aerial photographs) types. . . . “local” scale in the first group, the perceptive impacts of land- scape structures were estimated by means of ( ) the measure of the visible sky and of the different visible patches and corridors present in each slide (expressed as percentage of the slide surface), ( ) the measure of the perceived, ( ) the shannon–wiener diversity of enclosures different ecotopes (measured in step ). based on the theories outlined in the section and the literature review (e.g. stamps, , ; lange and bishop, ) these variables are relevant to the local spatial scale and are related to the natural-human perception scale (at the ground level). the visible landscape elements perceived were: open bare field, open maize field, water courses, tracks, hedgerows, banks, field grassed margins, buil- dings and sky. the enclosures, for their importance in environ- ment perception and preference, were estimated by means of the ratio between the percent of the per- ceived open space (ground plane excluded sky) ver- sus the percent of the landscape blocking features (vertical structures like hedgerows, buildings, banks) (stamps, ). shannon–wiener visual diversity was computed considering the well known formulation h = n∑ i= pi ln pi where p is the percent abundance of the i visible ele- ment and n is the number of visible elements. these two indices were utilized to synthesize some of the “preference framework elements” as complexity (the richness or diversity of perceived landscape fea- tures), legibility and prospect (related to the balance between open spaces and enclosures). based on the information processing approach (kaplan and kaplan, ) these elements, with coherence and legibility, build up the basic informational needs (involvement and the making sense) that drive the environmental preference. . . . “landscape” scale on the “landscape” scale, for the reasons already ex- plained in the section , the formal landscape content of the images that were to be related to human prefer- ence for landscapes (e.g. the images) was measured by circuitry, connectivity and density of real and planned d. franco et al. / landscape and urban planning ( ) – agroforestry networks, and by shannon–wiener diver- sity of patches. landscape pattern metrics were calculated using planland®© gis procedure for the same areas cor- responding to the photographs’ points of view ( km × ◦ radius area centered in the visual point). we de- fined a area for the indices calculation slightly wider than the visual field for technical problems, for exam- ple the needing to utilize the complete length of the observed hedgerow in the computation. the description of landscape pattern by means of indices has been attempted both to quantify the charac- teristics or modification of landscape structures (sup- posing they influence on landscape functions) and to measure some landscape parameters like connectivity, heterogeneity, fragmentation (e.g. for review: franco, ; gustavson, ). . . . landscape pattern metrics meanings the indices calculated here are the spatial metrics utilized in the gis procedure and have been already table visual quality criterion/descriptors elements of landscape images used in the vqc empirical procedure perceptive order: it is present a recognisable order in the visual elements of patches and corridors perceptive legibility: the open spaces and enclosure configuration allow to identified possible paths can be mystery: can be found refuge conditions and variable perspective are present single and/or isolated trees there is a strong presence of genius loci contrast and diversity of the landscape there is a sense of unity among the landscape elements the grain and diversity of the landscape permits a visual absorption capability (bell, ) the visual elements diversity creates interest (perceptive complexity) the ratio between the landscape elements and the empty/solid volumes ranges from / to / the horizon line is interrupted: the relationship between the landscape element shapes outlines closed spaces presence of water the presence of water is visible the visible water is clear, fresh and natural naturality–artificiality the conflict between the visual forces of the landscape and the direction, shape and position of artificial elements generates tension the enclosures have simple geometrical forms of no interest and/or the margin zones are missing watercourses are associated to vegetation character of vegetation trees dimension diversity contrast visibility identity and shapes of built in the visible buildings it is possible to recognise historical and/or architectural values selected for strength of information and lack of redun- dancy in the planning of agroforestry networks. the density of real and planned agroforestry plant- ings (m/ha) has a clear physical meaning. connectivity and circuitry are two indices that come from the graph theory and have been used in geography and in landscape ecology (forman and godron, ). they are based on the rate of the the- oretical and existing nodes and links of the network, do not have any intrinsic ecological meaning and need a series of conventions to be applied to the real world, in this case to agroforestry networks in the rural landscape (e.g. selman and doar, ). this indices estimate an “intrinsic” topological characteristic of a network that neither exists in its individual structural components (corridors), nor is simply accounted for by the presence/absence of the single components. in relation to this kind of structure these parameters are theoretically supposed to be correlated to some land- scape functions as biotic or hydrologic fluxes. several field and simulation studies give empirical support to d. franco et al. / landscape and urban planning ( ) – this hypothesis (fahring and merriam, ; forman, ; franco, ). the classic shannon–wiener diversity index tries to synthesize information about the richness and even- ness of landscape patches composition (e.g. forman, ) where a high value represents a rich composi- tion and even distribution. . . the vqc ex ante procedure the vqc is an empirical procedure (an expert rat- ing model) used to obtain a relative sbe during the de- sign development, and is presented as a video image (a cad environment three-dimensional rendering image based on the gis otput; e.g. franco, ) to be val- ued by an expert by means of a questionnaire, where each question corresponds to an elementary descriptor (table ). the descriptors represent the biophysical landscape features assumed to be indicators of land- scape scenic quality. the descriptors are derived from studies about the relationship of landscape human ap- preciation and about the landscape features influencing it (mostly appleton, ; bell, , ; bourassa, ; lamb and purcell, ; kaplan and kaplan, ; kellomaki and savolainen, ; lamb, ; schroeder, ; silvennoinen et al., ), and from a literature review of similar empirical models (e.g. scrinzi et al., ). this step allows for a judgment of a picture by breaking it down into common-value elements, followed by an analytical rebuilding. every criterion/descriptor assumes a value between (worst case) and (best case). the weighted mean of the op- erative criteria/descriptors of any one picture gives a synthetic and geocoded index of aesthetic appreciation or rebuttal, which can be processed with other simi- lar values. the aim is to support the design/planning process with relative estimations. all geocoded values are standardized within one index that has the same variation range as other indexes of the gis procedure. the reliability of the expert rating model was tested on four experts (professionals working on landscape planning and design, with two chosen from architec- ture studies, and two from ecological studies) who were asked to define each picture by using the empiri- cal procedure scheme. given the number of experts in the sample, the results were simply compared graphi- cally with the sb of the surveyed sample, representing the “social” perceptive value of the same landscapes. . results . . the influence of socio-economic variables on the citizens’ scenic beauty estimation in general ( ) young people give to sbe a lower value than other age classes (fig. a), ( ) respondents with high school degree and students (which actually overlap the “young” age class), and employees give a lower value than other classes (fig. b and c); except for employees, all of these tendencies are statistically significant. considering the interaction of socio-economic vari- ables it appears that, taking into account the age, the level of education influences the sb only in a sec- ondary way. the education effect depress the sbe in the young people, but become positive in the el- der classes (fig. d). finally it results that university students (“young” class) or employees with low level studies give lower values than others. other influences detected were based on interactions of a variety of variables and for this reason did not give very reliable final statistical sample. . . the influence of agroforestry networks on citizens’ scenic beauty estimation: site preferences all the sites with a planned agroforestry network were significantly preferred to the same sites without a planned agroforestry network (fig. ), as shown in the anova and duncan tests results (table ). results of non parametric and parametric anova were equiv- alent. the sb for each site was normally distributed (as theoretically expected), apart from the less (site ) and most appreciated cases (site a), that showed some skewness. the use of the differences between the sbe of the planted and not planted sites as depen- dent variable gave no results. . . the relationship between the influence of agroforestry networks on citizens’ scenic beauty estimation and the socio-economic variables in each socio-cultural category of the sample, the sites with the planned new hedgerow network were preferred to the correspondent sites without the hedgerow (fig. ). d. franco et al. / landscape and urban planning ( ) – fig. . here are plotted the socio-economic influences on the sbes of the whole sample. the anova probability values are: (a) age influence, p < . ; (b) study title influence, p < . ; (c) job influence (p < . ); (d) study title and age influence (ns). site preference ranking was never significantly dif- ferent among socio-economic classes, with the excep- tion of sex and partially for location. in these cases the difference was linked to one site (site ), that fig. . the box plots of the sbe of each real and simulated sites (the sites codes refer to those reported in fig. ). was given the highest value among the sites without hedgerows and the only image without hedgerow pre- ferred to some images with hedgerow. the site is sig- nificantly more valued by females and is preferred by lagoon citizens (venice and isles) (table ). all other insignificant sites ranking differences detected in each socio-economic class were always mainly attributed to this site, which was more valued by young, students and the unemployed. the image is different to others because of the presence of wa- ter, high visual diversity and equilibrium between negative (e.g. bare field) and positive (e.g. trees) ele- ments of perception value. only two other sites, the less appreciated among the images with the most dis- persed values, were ranked in a different way among socio-economic categories, but never significantly. there are little judgement differences between socio-economic classes in the case of the non agro- forested sites (sites – , fig. ), except for the site , less appreciated by farmland people (fig. c). d. franco et al. / landscape and urban planning ( ) – table results of the anova and the duncan test (main effect: sites) on the sb of the whole sample using the sites as factor variables site mean sbe homogeneous groups, � level = . . xxxx . xxxx . xxxx . xxxx . xxxx a . xxxx . xxxx a . xxxx a . xxxx a . xxxx a . xxxx a . xxxx anova summary of sites effects: d.f. effect, ; mean square effect, . ; d.f. error, ; mean square error, . ; f, . ; probability level, . . considering only the images with the planned agroforestry network, the “young” class gave sig- nificantly lower values for each agroforested site in comparison with other age classes (fig. a). among job categories farmers give higher and less spread val- ues than others (significantly as regards the students and the employees–professionals (fig. b). lagoon people give significantly lower and more spread val- ues for each agroforested site than people from other locations (fig. c). table sites ranking in the socio-economic classes that preferred the sites in a statistically different way site ranking by sexa site ranking by locationb site male site female sites venice–isles site mestre and suburbs site inland farmlands mean sb mean sb mean sb mean sb mean sb . − . − . − . . . − . . . . . . . . . . . . . . . . . . . . a . a . a . . a . a . a . a . a . a . a . a . . a . a . a . a . a . a . a . . . a . a . a . a . a . a . a . a . a . a . a . a . the site that produces the major effect is highlighted in bold. a f( , ) = . ; p < . . b f( , ) = . ; p < . . . . the relationship between scenic beauty and landscape variables at different scales . . . the correlation with the “local” and “landscape” scale variables the “social” mean sb values showed strong cor- relation even with “local” or with “landscape” scale variables (table ). in the first case significant correlation were detected with the percentage of visible hedgerows and sky, d . f ra n co et a l./l a n d sca p e a n d u rb a n p la n n in g ( ) – fig. . here are plotted the significant influences of socio-economic variables on the sb and/or site appreciation (the sites images and the codes significance are reported in fig. ); (a) age and site influence on sb; (b) job and site influence on sb, (c) location and site influence on the sites sb. in the plots (a) and (b) are not reported the sites and a (see section for explanations). d. franco et al. / landscape and urban planning ( ) – table spearman correlation between sbe and the “local” and “landscape” scale variables (see section for explanations) valid number spearman r t (n − ) p level “local” scale variables mean sbe and water − . mean sbe and vegetated banks . . . mean sbe and bare field − . − . . mean sbe and traks . . . mean sbe and margins . . . mean sbe and shannon–wiener visual diversity . . . mean sbe and enclosure . . . mean sbe and sky − . − . . mean sbe and agroforestry network . . . “landscape” scale variables mean sbe and patches shannon–wiener diversity . . . mean sbe and agroforestry network circuitry . . . mean sbe and agroforestry network connectivity . . . mean sbe and agroforestry network density . . . significant probability values are highlighted in bold. enclosure estimation and visual diversity. in the second case all correlation’s were very significant. . . . the regression models with the “local” and “landscape” scale variables no differences were detected between the regres- sion models of the whole sample and the regression models of the sub-samples based on the socio-econo- mic variables that showed a significantly different sbe, so only the whole sample results were consi- dered. even with high variance explained (table ) all lin- ear models tested had normality and linearity prob- lems, and for the most significant ones the explanatory variables selected were: shannon–wiener visual di- versity; the enclosure estimation; agroforestry network table the multiple linear regression model estimated for sb using the “local” scale variables β (s.e.) b (s.e.) t ( ) p level intercept − . ( . ) − . . sky . ( . ) . ( . ) . . agroforestry network . ( . ) . ( . ) . . enclosure − . ( . ) − . ( . ) − . . shannon–wiener visual diversity . ( . ) . ( . ) . . see section for the variables description. r = . ; r = . ; adjusted r = . . f( , ) = . ; p < . ; s.e. of estimate: . . and perceived sky percentages. lack of inference ro- bustness was influenced by the non linearity of some variables and the strong collinearity of others. the use of the piecewise linear model strongly in- creased the inference robustness of the model and the explained variance ( %). the scale change of the used dependent variables (from the “local” scale to the “landscape” scale) re- duced the confidence of the multiple linear regres- sion models tested, for collinearity, lack of linearity and normality problems. the strongest model among those tested is based on diversity and connectivity as explicative variables (table ). using intrinsically non-linear models increases the predictable robustness of the model (linearity and normality most of all) as explained variance does. by d. franco et al. / landscape and urban planning ( ) – table the intrinsically linear multiple regression model estimated for sbe using the “landscape” scale variables β (s.e.) b (s.e.) t ( ) p level intercept . ( . ) . . connectivity . ( . ) . ( . ) . . diversity . ( . ) . ( . ) . . r = . ; r = . ; adjusted r = . . f( , ) = . , p < . ; s.e. of estimate: . . applying best trade off between these two aspects of regression models reliability was obtained using di- versity, connectivity and circuitry as independent vari- ables (table ). . . . the relation between the sb and the agroforestry network density it is interesting to note that density is related to the sb in a bell-shaped way (fig. ), as expected in a reforested landscape (hunziker, ). the relation it is necessarily partial because this study refers to a real hedgerow planning design, where density threshold is limited by the optimization constrains of conflicting agroforestry functionality in a specific rural landscape (with its agricultural model and allotment). the outlier sb value (site a) correspond to the most appreciated landscape, with a clearly visible water course. in the case of the site a (the most appreciate) the presence fig. . it is plotted the relationships between agroforestry network density and sbe. the outlier sb value (site a) correspond to the most appreciated landscape with a clearly visible water course. table the intrinsically non-linear multiple regression model estimated for sbe using the “landscape” scale variable (piecewise linear regression with breakpoint) estimate constant b . circuitry . connectivity . diversity . constant b . circuitry . connectivity − . diversity . breakpoint . final loss: . ; r = . ; variance explained: . %. of the channel strongly influence the hedgerow density and sbe relationship. . . the test on the vqc empirical procedure the results of the vqc empirical procedure test are reported in fig. . they show a good correspon- dence between the ex ante procedure outputs (used in the gis procedure to forecast the sb) of the four ex- perts, and the mean “social” sbe for each site. the values estimated by means of vqc are always inside the s.d. range of the social response to the landscape perception. d. franco et al. / landscape and urban planning ( ) – fig. . comparison between the outputs of the vqc empirical procedure by the four experts and the “social” sbe for each site (see text for explanations). the sites images and the codes significance are reported in fig. . there appears to be a difference between the architecture and non-architecture designers tested, the second group being closer to mean social sb values. this is a first assessment of the testing, a deeper valuation would require a statistical sample of experts. . discussion in those cases where there is a slightly significant influence of some socio-economic variables on this type of aesthetic landscape evaluation, this has been found to be mainly due to the factor of age. in fact other socio-economic variables that influenced sb, as the (university) “student” and the “high school degree” classes (fig. ), corresponds, ultimately, with the “young” class. this result is consistent with some studies but not with others (daniel and boster, ; lyons, ; tempesta and crivellaro, ). all the strata of the sample show the same trend regarding the sites valuation (figs. and ). given that the appreciation framework for this landscape appears to have a common basis, it would appear that—at this level—differences in visual agree- ment are of cultural origin. differences have been detected for categories of people who lack personal or socio-cultural experience (which is not necessarily learned at school), or who have probably the need for personal affirmation and/or personal re-equilibration from strong aesthetic or functional models (for exam- ple, the valuation of the elder graduates was closer to the mean sb values of the whole sample—that is, the “society” sb—than that of the university students of urban or environmental fields). with regard to the specific role of the agroforestry networks on landscape perception, this was consis- tently found to be positive, at a statistically signifi- cant level (fig. ; table ). this result is consistent with other studies on rural landscape appreciation in the same area (venetian flat, tempesta and crivellaro, ), and in general in those landscapes that appear to be partially reforested (see for review hunziker, ). in this case, all sites with planned agroforestry net- works were significantly preferred to the same sites without them, and all socio-economic categories ap- preciated the same sites in the same way (fig. ), d. franco et al. / landscape and urban planning ( ) – even if there were some differences in the weight and distribution of the values. differences in sites appreciation ranking seems to be secondary and linked to different perception role in some socio-economic classes, of cultural or deeper types. in this case, the most significant difference that was actually detected in the site ranking was based on gender and was in relation to a single image that was dominated by the presence of water (table ; fig. ). the sex-based difference in perception may have been either coincidental or linked with an intrinsically dif- ferent response to the presence of. it is not possible to go beyond such speculations on the basis of our data, but these results support similar results of more de- tailed studies on this topic (e.g. bourassa, ) and does not challenge previous agroforestry appreciation results. in the other cases, the differences are more clearly linked to cultural stimulation: the image with wa- ter also influenced the lagoon citizens and this may not be a chance finding, however, because the same category is influenced by questions linked to wa- ter and, in particular, water quality (mannino et al., ). the role of an agroforestry network appreciation (in terms of mean sb value and its dispersion) increases with age, type of activity and location of domicile: these variables are reasonably linked to the respon- dents wisdom/experience, management role in the landscape and sense of landscape belonging. given that the other connections are clear, in the first case the relationship between age and wisdom/experience is reasonable because it is not based on a particu- lar technological expertise, but on a general, sound experience about the life in the landscape and in its cultural heritage (with deep and strong historical roots). the university appears to influence the “young” to- wards a perception and an emotional response that are different to what was found for the whole sample. this, in turn, is probably due to both a learned aes- thetic and cultural models that contrast with, or have a different weight from what the community has, and/or may be due to a lack of information (brunson and reiter, ) about the role of these landscape struc- tures (franco et al., ; mannino et al., ). having verified that ( ) even if some socio-economic variables do slightly influence the citizens’ landscape aesthetic perception they actually do not influence the preference trend of the observed rural landscapes (e.g. everybody assigned the same kind of judg- ments to the same sites, even if with some intensity differences), ( ) these socio-economic variables have no significant influence on the positive role of an agroforestry network in landscape appreciation, ( ) these socio-economic variables do not influence the regression models outputs of sbe, we then tried to look for relationships between landscape descriptors and the whole sample (“social”) sb. the “local” scale variables most strongly correlated to sb have been visual diversity, enclosure estimation, and the presence of attractive elements like trees and water. these results are empirically consistent with several common foundations of the theories produced on this topic, and outlined in section . the correlation calculated between sb and “landscape” scale metrics in the same site were always positive and significant, showing a non-functional relationship between sb and landscape pattern. in the presence of diversity in landscape patches and of agroforestry network efficiency, the quality of land- scape perception increases. these relationships were estimated by means of regression models, that are weak because of non- linearity, non-normality and collinearity of some variables. the problems of inference robustness are greatly reduced by using intrinsically non-linear mod- els, which could allow for their use as applicative tools. functional relationships are evident between landscape appreciation and ( ) some composition relations of perceived elements (diversity, enclo- sures), and ( ) some visual elements (percentage of sky, percentage of trees and shrubs plantations). again the results are empirically consistent with the founding elements of the theories outlined in section . on the basis of these data, it is not possible to clarify more the significance that the characteristics of these single visual elements have in the sbe. we cannot, for example, specify the influence of single aspects of plantation (composition, structure, season) or water (color, river banks). other researchers have investigated these effects (e.g. gregory and davis, ; kellomaki and savolainen, ; lamb and purcell, ) and we can only indirectly confirm the importance of water in landscape evaluation and d. franco et al. / landscape and urban planning ( ) – state that the presence versus absence of agroforestry systems is a strong explanatory variable of landscape appreciation. by changing the scale of analysis, the functional relations between sbe and landscape pattern are confirmed. the increasing compositional diversity of landscape and the increasing structural efficiency in the agroforestry network increase landscape ap- preciation. in this case, the relationship is not sim- ply determined by the partly bell-shaped function (hunziker, ; fig. ) between the increase of agro- forestry systems and sb (density is not selected in the best regression models), but between “intrinsic” characteristics of the agroforestry network (here es- timated by connectivity and circuitry) and landscape appreciation. at the “landscape” scale of analysis/perception, therefore, there are those intrinsic characteristics of the network (a structure that does not exist at the “local-patch” scale) that appear to influence the agro- forestry network role in landscape beauty appreciation. this appears to be a particularly important out- come, because the same results have been obtained when very different kinds of landscape processes have been linked to the agroforestry network: both wind and non-point source pollution control (franco, ). in each case, the explanation for network behavior in empirical simulation analyses showed a stronger re- lationship with the “intrinsic network” characteristics (measured by connectivity and circuitry) than presence on its own (as estimated by density) (franco, ). the regression models were useful in the investiga- tion of the functional relationships between variables and, in the case of piecewise models, to give potential empirical tools for design. in this case, the variables selected in the final models were not highly correlated for the strong formal resemblance of the algorithms. the expert rating empirical estimation of sb uti- lized by the gis procedure shows a high level of agreement with the mean “social” sb. even though it is only a qualitative test, the results are interesting enough for further investigation and show that some of the criteria/descriptors utilized in the vqc proce- dure and investigated in the study (such as the pres- ence of vegetation, the ratio of open/closed space, and visual diversity) are—as expected—significantly and functionally linked to landscape perception and value. . conclusions the conclusions presented below address each of the aims of this paper, as outlined in section . aim : irrespective of whether or not there were some statistically significant influences from socio-economic variables on the sb of the rural land- scape investigated (e.g. the sb of the whole sample of the pooled sites), every socio-economic category gave the same kind of judgment for the same kind of landscape. in other words, the statistical measure of sb for the whole sample for each landscape repre- sented the “society” measure. the partly bell-shaped relationship between the agroforestry systems pres- ence (hedgerow) and sbe was one of the factors that influenced the sample appreciation of this kind of landscape. the socio-demographic influences that were identified were generally culturally determined, and mostly generated by age differences: the appre- ciation of the presence of an agroforestry network increases with some factors (age, activity and location of domicile) that can reasonably linked to the level of wisdom/experience, landscape management role and sense of belonging. these factors were the same that influenced the contingent values that were assigned to this landscape structure by the same sample (franco et al., ) and they have been already pointed out as driving forces in a landscape appreciation process (e.g. o’neill and walsh, ). there was, however, one case for which the influ- ence on landscape preference might have been of a deeper origin, due to sex and linked to the presence of water. even if the data for further investigation were not available this result it is coherent with results the other studies on this topic. aim : each site that had planned agroforestry net- works was significantly preferred to the correspond- ing one without such networks. this result show that a positive impact on landscape perceptive valuation was produced by the simulated output of the planning sys- tem (planland®©) that was utilized to optimize the role of agroforestry networks in landscape amelio- ration undertaken from the conservation, agronomic, economic and hydrological points of view. aim : the landscape variables used for the anal- yses of the “society” sb value of the rural land- scapes, were defined on the scales for the “local” (human-natural, ground level) and for the “landscape” d. franco et al. / landscape and urban planning ( ) – (not human-natural, aerial photographs) perceptive. given the number and characteristics of the variables selected, in the case of the “local” scale, the variables (the percentage of visible elements in each picture and the indexes of visual composition) that were selected by correlation and regression models were in accordance with theoretical expectations for the importance of visual diversity, of enclosures, of sky horizon level and of the presence of plantation. for landscapes such as the one that was analyzed, and for the agroforestry perceptive impact estimate, the re- gression model tested at this scale could be useful as a quicker and simpler empirical tool for design at the “local” scale than that created for the planland®© planning system (vqc). in the case of the “landscape” scale, a sound ex- planatory functionality was found between sb and the used landscape pattern metrics, and it appears that • landscape pattern metrics selected in the plan- land®© gis procedure for the analysis and de- sign of agroforestry network optimization showed a good explanatory power for the utilized sb (which represents in this case the estimate of a “social” process of landscape perception, cognition and val- uation); • in the case of the agroforestry network metrics, the main explanatory factor lies not simply in the partly bell-shaped relation with the density, but in the intrinsic characteristic of the agroforestry net- work (a landscape structure that does not exist at the “local-patch” scale level) that is described by connectivity and circuitry; • it is reasonable to expect that the impact of the agro- forestry network on sbe could be analyzed and predicted with the empirical regression models ob- tained, in view of their affordability, simplicity and speed. aim : even though the utilized test was only graphic and not statistical, the expert rating percep- tive estimation procedure used in the planland®© gis planning system produced a high level of agree- ment with the sbe research results, and the results are interesting enough for further investigation, even if the procedure is weaker than representative models from the theoretical point of view and is very time consuming (both for three-dimensional rendering simulation and for the expert response elaboration for each single selected point of view). the vqc proce- dure has been carried out for perceptive estimation of a generic landscape, but gave good results for this kind of rural landscape. in conclusion, we believe that the optimization of wind control, water quality control, agronomic effects, economic cost and benefits, and aesthetic perception can be reached if all these processes are treated as landscape functions affected by landscape structure (including both agroforestry plants and networks) at different scales. applying this approach, the results 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(ed.), humanistic and behavioural geography in italy, pisa, pacini, , – . daniel franco ( ) is a professional landscape ecology ( ) and a contract professor ( ) at the faculty of environmental sciences at the ca’foscari university of venice. he is inter- ested in several application (non point source pollution control, planning, environmental management and design) or cultural (socio-economic and aesthetic evaluation) aspects of this disci- pline. he gives or gave courses of environmental management and design and landscape ecology. for more details go to www. danielfranco.org. davide franco ( ) is a specialist of statistical and numerical modelling of estuarine and coastal zone. venice lagoon and the brazilian south coast are his preferred study areas. he is professor of hydraulics ( ) at the federal university of santa catarina (ufsc), brazil. he gives and gave course of environmental mod- eling, environmental data analysis, time series analysis and mul- tidimensional spectral analysis at the ufsc’s graduate program (gp) of environmental engineering, and since is dean of the “use and protection of coastal environments” area of this gp. ilda mannino ( ) is graduated in environmental science ( ) at faculty of environmental sciences at the ca’foscari uni- versity of venice, and has attended several post graduated course (international advanced school leonardo da vinci, in bologna, port authority of venice). at the moment she is taking a phd in coastal zone management, from the department of environmental science, at the venice university. www.danielfranco.org www.danielfranco.org d. franco et al. / landscape and urban planning ( ) – gabriele zanetto ( ) is fulltime professor ( ) of economic geography and dean ( ) of the faculty of environmental sci- ences at the ca’foscari university of venice. he is a specialist of human organization of the environment, involving cultural and economic elements and statistical, cartographic, mathematical modeling. venice has been a relevant field for testing his theoretical propositions. he gives or gave courses of environmental policy, environmental economics, education to the environment, teaching of geography, economic geography, geography of tourism, human geography. the impact of agroforestry networks on scenic beauty estimationthe role of a landscape ecological network on a socio-cultural process introduction methods respondents procedure landscape descriptors "local" scale "landscape" scale landscape pattern metrics meanings the vqc ex ante procedure results the influence of socio-economic variables on the citizens' scenic beauty estimation the influence of agroforestry networks on citizens' scenic beauty estimation: site preferences the relationship between the influence of agroforestry networks on citizens' scenic beauty estimation and the socio-economic variables the relationship between scenic beauty and landscape variables at different scales the correlation with the "local" and "landscape" scale variables the regression models with the "local" and "landscape" scale variables the relation between the sb and the agroforestry network density the test on the vqc empirical procedure discussion conclusions references universal journal of educational research ( ): - , http://www.hrpub.org doi: . /ujer. . on the life aesthetics of aging people- slowness makes life beautiful kuei-chiu chang , mei-ju chou ,* general education center, department of hospitality management, taiwan shoufu university, taiwan department of early childhood education and center for teacher education, national pingtung university, taiwan copyright © by authors, all rights reserved. authors agree that this article remains permanently open access under the terms of the creative commons attribution license . international license abstract taiwan has a rapid increase of elder population, which is supposed to double within the next years. however, lifelong aesthetics learning for the elderly has not yet been fully developed. in the environment emphasizing on lifelong learning with increasing elder people, it is a crucial mission to design appropriate environment, curriculum, leisure activities for elder people in their later life. under such premise, this study aims to explore various theories and try to evaluate and elaborate on aesthetics in diverse ways: kant, nietzsche and hegel are the contributors to the theoretical perspectives on aesthetics. with the theories supporting the application of life aesthetics in the lives of seniors, this study finally concludes that aesthetics is crucial for the elderly as it improves life quality, physical, psychological health, social connectedness and continuous learning. keywords life aesthetics, elder people, social connection, physical health, psychological health . introduction taiwan has a rapid increase of aging population, which is supposed to double within the next years. however, aesthetics lifelong learning for the elderly has not yet been fully developed. in the environment emphasizing on lifelong learning with increasing numbers of elder peoples, it is a crucial mission for us to design appropriate environment, curriculum, leisure activities for elder people in their later life (leung, lui & chi, ). especially, due to the fact that in , taiwan ministry of education published "the white paper of elderly education" has announced taiwan has entered the lifelong learning century. in order to encounter the challenge derived from scientific achievement, globalization competition, internalization currency, and knowledge economy challenge, the series of elder people’s service learning, food, clothing, housing, transportation, and community learning, taiwan ministry of education established active aging learning resource center to cooperate with township district office, public libraries, community colleges, social welfare groups, community buildings, and etc. for more than years, the value of aesthetics education have been acknowledged and regarded as an influencing factor for development of healthy individual in chinese culture. further insight into the influence of aesthetics onto individual’s lifelong learning has been proved by recent research. (lim, ; linda & margaret, ). the advancement of aesthetic awareness is related by the feel of environment, sound, color, taste, and sights. with the importance of aesthetic life philosophy, this study aims to relate the life aesthetics and elder people’s leisure activities, curriculum, and life rhythm. aesthetics refers to a group of principles or values that relate to nature and the appreciation of beauty in art or environmental factors. it is a philosophical and a psychological process. food, housing, clothing and transportation are some of the aesthetic characteristics that have a connection to the leisure activities of elder people, and everyday aesthetics focuses on the events that take place on a daily basis in an individual’s life. apart from focusing on the fine arts of the natural environment, everyday aesthetics involves leisure activities such as modes of commuting, the undertakings at workplaces and other amusement factors. life aesthetics is imperative for seniors or the elder members of the society as the activities affect their social connection status, and psychological and physical health. slowness is a major characteristic of the elderly and elicits the necessity for a motivating factor that would reverse the effects of old age (brogan, ). by aesthetics, such individuals are enabled to overcome the adverse effects of old age and bring out functions in their environments and social lives. . theories of life aesthetics various theories try to evaluate and elaborate on aesthetics in diverse ways. those theories support the application of on the life aesthetics of aging people- slowness makes life beautiful life aesthetics to life of the senior. all the theories concur on the fact that aesthetics is crucial for the elderly as it improves life quality and continuous learning, and kant, nietzsche and hegel are the contributors to the theoretical perspectives on aesthetics. (i) kant’s theory of life aesthetics kant’s prepositions are based on universality, imagination and intellectual abilities. to advance his perspective, kant explains the problems of judging beauty of aesthetic factors such as art and the processes of deducing or coming up with personal tastes or preferences. kant’s critique of judgement tries to explain the reasons behind people’s judgements and manner in which they consider certain things as beautiful and others as non-attractive. according to kant, aesthetic judgments must have four distinctive features (berger, ). first, aesthetic judgments are disinterested (mcmahon, ); that is, people tend to take pleasure in certain things because they deem them as beautiful and rather than pleasurable. second, those judgments are universal on basis of universality in kant’s theory. under universality, it is expected that a particular judgement gains support from other people other than the individuals that formulate them. thirdly, kant proposes that the judgements are necessary in the nature of human beings, so seniors also need aesthetics to live a comfortable life in old age. however, kant asserts that necessity and universality are products of the human mental imagination and may not necessarily be the actual features of objects or pieces of art. his conclusion is that there is no objective feature that makes an object beautiful, since beauty is dependent on personal judgements and imagination. people develop tastes or preferences founded on the aesthetic judgments making on certain issues. in addition, beauty is a feature that draws attention and people tend to make choices based on how beautiful a particular object is. according to kant’s theory, beauty does not have a purposive concept; instead, people attach some significance to it because of the imagination and judgments they have made. based on kant’s theory (mcmahon, ), slowness among aging people is significant due to their personal judgments and ways of doing things. on basis of their life experiences of aesthetics appreciation, exploration, expression and creation, elder people can live comfortably by observing life aesthetics and avoiding negative judgments from other people. a person’s judgment is treated as an independent opinion that may not be true, while appreciating forms of beauty and its own appearance is fundamental. beauty's connection with art, nature and their social lives is consequently improved. concerning kant’s theory on seniors’ life aesthetics arrangement in physical and psychological life, it focuses on the explanation of individuals’ intellectual abilities and imaginations. psychologically, seniors have unique tastes and preferences according to their personal cognitive imaginations or judgments, which constitute the psychological lives of seniors owing to aesthetics' influence on their reasoning and imaginative ways, while psychological conditions have a direct bearing on the physical life of seniors or other individuals. (ii) nietzsche’s theory of aesthetics nietzsche's assertion focuses on metaphysics and beauty. according to the theory, beauty is relative to and dependent on personal opinions. human beings transform the world on foundation of their preferences, nietzche's theory suggests that life has no meaning apart from the one human beings endow it with their preferences. in this respect, seniors are usually slow and less aggressive due to their old age. however, they also need to appreciate beauty and mold their environments subject to their preferences. in this sense, elder people make use of life aesthetics to achieve life goals. in addition, the theory suggests than humanity is the only beautiful thing with characteristics such as power, pride and courage. nietzsche’s theory deducts that the beauty of the world can only be justified when it becomes an aesthetic product. nietzsche defines art as a metaphysical complement that allows the transcendence of flora and fauna other than an imitation of nature (byrne, ). the theory adds that art is a source of perfection and joy. therefore, life is sustained by art's making it endurable and worth living. conclusively, art maintains, enhances and affirms life. nietzsche’s theory (adorno, ) supports the importance of aesthetics life in elder people’s life values and quality. regardless of the physical state, elder people require aspects like art that would enhance their lives and justify reasons for them to continue living. aging comes with various challenges. the most common one is the fact that body weakens and wrinkles appear on the skin. the characteristics of old age make people insecure about their appearance and they may pursue risky solutions such as plastic surgery. however, nietzsche’s theory merges beauty, art and metaphysical aspects of nature. nature enables aging people to appreciate beauty in their own context in substitution with the perceptions of other people. in the end, such individuals are able to view themselves differently and appreciate the beauty that exists in their abilities. art is one of the ways through which seniors can express their abilities to counter physical inabilities. considering nietzsche’s theory on seniors’ life aesthetics arrangement in physical and psychological life, elder people undergo various physical changes as they grow old. therefore, beauty and metaphysics bring up the aspects of physical looks and psychological satisfaction. according to nietzsche, beauty is a product of aesthetics. therefore, the aesthetic lives of seniors gives them confidence in the way they look and are able to define beauty in their independent perspectives. on the other hand, metaphysics is based on art which provides seniors an opportunity to engage in useful excursions that would generate psychological serenity for participation in what they love. universal journal of educational research ( ): - , (iii) hegel’s theory of aesthetics hegel’s theory bases its facts on the mind and enlightenment or bildung (kedney, ). contrary to kant’s theory, hegel's claim applies a more precise and extensive focus on beauty and art, and his philosophy analyses the institutions required if humanity, in this case, spirit, is to be self-determining and free. such institutions include educational facilities, family and the state. at this point, the theory reiterates the imperativeness of lifelong education, and the elderly are encouraged to engage in educational processes throughout their lives to enhance their spirit and social connection. for hegel, art is figurative. the role of art is to express freedom in the correct context, which is fulfilled by the expression of freedom of spirit in its sanctified form without the normal life contingencies. for instance, old age is a life contingency but it would not hinder the quality and effects of art. the ideal freedom expressed through art constitutes beauty, which is fundamental in the study of life aesthetics (comay, ). according to hegel’s assumptions, he is of the opinion that his perception on art is both normative and descriptive. he perceives his account on art gives a description of the principal features of the exquisite works of art attributable to the western tradition. elder people are slow, but they could still engage in art and obtain satisfaction and relevance, since contented with oneself is imperative for appropriate psychological health. beauty and appearance are major components of aesthetics, and that is why hegel presupposed that formal beauty is found in nature. nevertheless, true aspects of beauty are evident in artistic works only. human beings in an expression of their cognitive thoughts and creativity create beauty of art. in this regard, the elderly may not be able to engage in rigorous physical activities, and they can use art to express their mental thoughts, making themselves useful other than a burden to others. however, according to hegel’s theory, beauty is not limited to the physical form, instead, it also takes content into account, which is one of hegel’s most controversial ideologies. the content referred by hegel is freedom of spirit as well as serenity. therefore, according to the theory, the incarnation the freedom of spirit is a visible expression that can be seen throughout art. bidung is defined according to hegel’s perspectives on the spiritual aspect. the aesthetic power of bidung could arouse older people’s confidence and autonomy, and it could also be a source of motivation for the elderly enabling them to make relevant reflections and change their attitudes towards life and friends. such actions demonstrate the fundamental elements of the philosophical view of bidung, including feeling, acting, thinking and wishing. such processes initiate recreational and educational activities considerate of both individual and social ethics. when the senior or elder individuals change their attitudes and incline their daily activities towards better philosophical practices, they could achieve an improved physical and psychological health. considering hegel’s theory on seniors’ life aesthetics arrangement in physical and psychological life, hegel explained that life aesthetics focuses on psychological factors and enlightenment, suggesting that art is an expression of the freedom of spirit. psychologically, seniors are free to express their feelings, emotions and creativity through art. in the context of physical life, kant’s theory suggests that aesthetics initiate a change in attitude towards life in seniors. subsequently, seniors are able to tailor their lives to accommodate aesthetic practices both psychologically and physically healthy. . the application of life aesthetics to seniors’ daily life life aesthetics shapes the manner in which old individuals behave and engage the challenges they face. the adoption of life aesthetics by the elderly assists them fitting into the society and finding the activities that interest them and in which they can actively engage. as a result, seniors can fit into the society, relate appropriately with others and even engage in lifelong education. the focus of geriatric aesthetics is on the emotional and physical needs of elder persons. in geriatric aesthetics, health-conscious grooming in terms of clothing and hygiene is considered as vital as healthy diets. if an individual lacks either health-conscious grooming or healthy eating schedules, the resultant life quality diminishment will make elder age hazardous. geriatric aesthetics specialists are able to recognize psychological and physical conditions related to elder's mind and body. therefore, the specialists respond appropriately without aggravating the condition already in existence and able to initiate the referral of the victim to a relevant advanced care institution (miyahara, ). basic hygienic practices such as brushing teeth, maintaining neat hair nails and general grooming begin at a young age. proper hygiene initiates the development of the somatic immune system. it should be noted that even as we grow old, we still require a strong immune system to survive through old age. grooming enhances confidence in oneself and becomes more imperative as people grow older (melchionne, ). self-worth and beauty are integral aspects of aesthetics. looking presentable results to an enhanced sense of self-importance and promotes both physical and mental health. other aesthetic aspects such as painting, building a house and writing a book gives individuals feeling of accomplishment, self-respect and pride. an enhanced self-worth gives life some sense in the case of senior individuals. geriatric aesthetics is a specialty field of practice resulted from the rising population of elder adults in the global demographic systems. the profession provides a link between the aesthetic changes that are paramount when an individual ages and their relationship with old age (smuts, ). on the life aesthetics of aging people- slowness makes life beautiful (i) positive relationship between life aesthetics and the physical health of seniors as human grows up, the body systems become more complex and are fully mature at adulthood. similarly, as an individual grows old, so does the body. physical fragility and weakening of the body causes somatic strains. some of the victims may become partially inactive and require assistance from younger individuals for instance when they want to move (perniola, verdicchio & silverman, ). therefore, elder people require a method that they can use to overcome such effects, and this proves that life aesthetics may be the answer to physical strains and disorders among the old population. physical health conditions are common when body parts age and become less functional. elder people may find it difficult to move and engage in daily activities. in this regard, life aesthetic practices engaged in physical activities and interesting art excursions keep old adults agile (pan, ). additionally, physical health care through geriatric aesthetics assists in maintaining appropriate wellbeing and fitness. for instance, skin care is imperative because it expresses a lot about an individual’s appearance and has a direct effect on how aging people rate their self-worth (sampsel, ). living conditions or housing also constitutes life aesthetics. elder people are fragile and should live in geographical areas free of health hazards. architectural designs should also be considerate of the fact that most of the elderly individuals are physically less mobile or may not be able to move at all. housing plans should be formulated in a manner that favors easy mobility of old persons (shimamura & palmer, ). transport is also another area of concern in the discussion of life aesthetics in relation to old adults. when commuting, elder people should consider their physical health and use favorable modes of transport. and, when moving over short distances, walking would be desirable because it would make them physically fit and maintain the functionality of their locomotion structures. consequently, life aesthetics has a direct bearing on the physical health of elder individuals. maintaining hygienic practices and physical exercises improve health conditions for elder people. transportation may appear to be a simple mandatory day-to-day practice, but it also affects individuals’ health. that is to say, if elder people ignore life aesthetics, they may fall captive to physical disabilities. for instance, reluctance to engage in physical activities may lead to the dysfunctionality of limbs, making the victims physically handicapped (adorno, ). (ii) positive relationship between life aesthetics and the psychological health of seniors psychological health is just as important as physical fitness. mental strains occurring when an individual is aging can lead to psychiatric disorders. the serenity and sobriety of the mind is vital for elder adults, and psychological stress can lead into other complications like fatal heart conditions. life aesthetics assists aging people to avoid instances of psychological health complications (miyahara, ). from the provisions of geriatric aesthetics, life aesthetic aspects such as eating healthy food and grooming appropriately enhance the confidence of elder adults. it is part of human nature to care for our appearance and people’s perceptions. old adults may focus more on their appearance because of the undesirable physical aspects of aging age. however, it they worry too much about physical appearance, they may develop dysmorphic disorder, a psychological condition (lee, ). the disorder is common among patients with bulimia, anorexia as well as individuals undergoing plastic surgery for the belief that their appearance is not pleasant. life aesthetics enable such individuals to maintain their bodily appearance and psychological health simultaneously. consequently, psychological disorders resulted from low self-esteem among old adults is avoided (goldie & schellekens, ). (iii) the positive relationship between life aesthetics cultivation is and seniors’ social connectedness/interpersonal relationship/interrelated relationship life aesthetics enhances the physical and mental health of elder adults and consequently improves their relationship with other people and the environment. social connection is essential for the elderly, since they do not desire to be neglected by other members in the society. taking part in substantive activities in the society makes elder individuals relevant and inculcates the sense of connection. feeling important is a fundamental aspect of high self-esteem that elevates an individual’s self-worth regardless of aging (stecker, ). once elder adults are able to develop an appropriate level of social connection, they are able to establish good interrelationships within the society. life aesthetics such as art brings different people together with interests in artistic designs. in this way, art initiates social relationships between people with similar interests. when aging people engage in art or nature excursions, they could meet diverse people with whom they could relate and socialize with (kreitman, ). family relationships amongst elder individuals, children, grandchildren, relatives and even friends are crucial. life aesthetics plays a major role in enhancing relationships within families. engaging is leisure activities together enhances family bonds and integrates elder individuals into the family setting as they a role to play. family attitudes have a direct effect on the lives of the elderly adults. therefore, family ties are an imperative aspect of life aesthetics with regard to the elderly individuals (kosnoski, ). consequently, life aesthetics are imperative for maintenance of appropriate health conditions for elder adults both physically and psychologically. engagement of old individuals in physical and leisure activities enables them to live healthy lives and initiate social interrelationships with others and nature. for instance, the friendly warmth around universal journal of educational research ( ): - , traditional farmers elevates life aesthetics among the old. aesthetic sensibility and creativity and the creation of an appropriate community for older people to live in, are also elevated (ugwueze, ). (iv) lifelong education of seniors in the normal setting, education is for the young individuals. however, life aesthetics enables integration of education and aging. apart from art, leisure and physical activities, seniors can also engage in lifelong education to maintain their assertiveness and knowledge. as research shows, education in the latter years offsets high dependency rates and reduces the prevalence of disorders resulting from both physical and mental inactivity (simpson, ). education in the later stages elicits happiness among those involved and widens their integration and connection to the society. education of the seniors brings elder individuals with similar interests together (titmus, ). meanwhile, companionship in the course of learning leads to a healthier life because individuals are able to share their experiences with old age and learn from each other. for instance, most erlderly have retired from previous jobs and may miss the company of workmates, so the education of seniors remedies the loneliness that characterizes old age (monahan & clancy, ). . conclusions aesthetics is a philosophical and psychological concept that entails principles related to nature and the appreciation of beauty as an aspect of humanity. life aesthetics involves activities such as leisure engagements, lifelong education, physical exercises, nature excursions and art. life aesthetics is significantly vital for the elder members of the society. most of the elderly individuals desire to live healthy lives and this motivates them to engage in life aesthetics (stroud, ). various theorists have been formulating different definitions of aesthetics. three examples of the perspectives have been formulated philosophers, namely kant, nietzsche and hegel. kant based his arguments on intellectuality, universality and the imaginative ability of the human minds, with assertion that humans are free to make independent judgements and deductions (bashford, ). nietzsche centered his theory on metaphysical aspects and beauty; and according to the theoretical preposition, beauty is relative. lastly, hegel’s theory focuses on the cognitive mind and enlightenment of bildung. life aesthetics affects the physical and psychological health status of old individuals. physical activity and geriatric aesthetics reduces the incidence and prevalence rates of disorders related to aging issues. education of seniors is also a notable aesthetic principle. by learning at the elder age re-integrates seniors into the society and develops their social connectedness and knowledge (jarvis, ). references [ ] adorno, t. w. 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( ). “aging people are useless”: representations of aging on the simpsons. canadian journal on aging/la revue canadienne du vieillissement, ( ), - . ‘the most beautiful of wars’: carl von clausewitz and small wars sibylle scheipers accepted for publication by the european journal of international security, june abstract: carl von clausewitz was both an avid analyst of small wars and people’s war and, during the wars of liberation, a practitioner of small war. while clausewitz scholars have increasingly recognised the centrality of small wars for clausewitz’s thought, the sources and inspirations of his writings on small wars have remained understudied. this article contextualises clausewitz’s thought on small wars and people’s war in the tradition of german philosophical and aesthetic discourses around . it shows how clausewitz developed core concepts such as the integration of passion and reason and the idea of war in its ‘absolute perfection’ as a regulative ideal in the framework of his works on small wars and people’s war. contextualising clausewitz inevitably distances him from the twenty-first-century strategic context, but, as this article shows, it can help us to ask pertinent questions about the configuration of society, the armed forces and the government in today’s western states. keywords: clausewitz; people’s war; kant; schiller; aesthetics introduction the classical perception of carl von clausewitz up to was one that depicted him as the paradigmatic thinker of regular interstate wars. since , the year that saw the publication of two seminal books on clausewitz, peter paret’s clausewitz and the state and raymond aron’s penser la guerre, clausewitz scholarship has moved on considerably. the clausewitz reception in the past peter paret, clausewitz and the state: the man, his theories, and his times (princeton, nj: princeton university press, ); raymond aron, clausewitz: decade has continued the appreciation of clausewitz as a thinker of small wars as well as large wars. it has acknowledged that clausewitz himself did not subscribe to a binary view of war that distinguishes between these two as fundamentally different forms of war. beatrice heuser’s work on clausewitz as a thinker who lived at a ‘watershed’ moment between partisan warfare and people’s war also emphasized the centrality of small wars for clausewitz’s thought. this article expands the study of clausewitz’s analysis of small wars by highlighting the relevance of moral and aesthetic elements for this analysis. it demonstrates how clausewitz engaged with his contemporary aesthetic and philosophical context, in particular the ideas of kant and schiller, in order to understand the transformation of small wars from partisan warfare to people’s war that occurred during his lifetime. clausewitz developed his understanding of people’s war – ‘the most beautiful of wars’ [‘der schönste aller kriege’] – as war in philosopher or war (englewood cliffs, nj: prentice hall, ). see also hew strachan, ‘clausewitz en anglais: la césure de ’, in laure bardiès and martin motte (eds), École pratique de la guerre? clausewitz et la pensée stratégique contemporaine (paris: economica, ), - . hew strachan, carl von clausewitz’s on war: a biography (new york: atlantic books, ); andreas herberg-rothe, clausewitz’s puzzle: the political theory of war (oxford: oxford university press, ); antulio j echevarria ii, clausewitz and contemporary war (oxford: oxford university press, ); christopher daase, ‘clausewitz and small wars’, in hew strachan and andreas herberg-rothe (eds), clausewitz in the twenty-first century (oxford: oxford university press, ), pp. - . beatrice heuser, ‘small wars in the age of clausewitz: the watershed between partisan war and people’s war’, journal of strategic studies : ( ), pp. - . see also the contributions in the special issue of small wars and insurgencies : ( ) ‘the origins of small wars: from special operations to ideological insurgencies’. ‘ein ungenannter militär an fichte’, printed in carl von clausewitz: geist und tat, edited by walther malmsten schering (stuttgart: alfred kröner verlag, ), p. . its existential form in what we could call a dialogical process with kantian and post-kantian philosophy around . the phenomenon of people’s war confronted clausewitz with the question of how to integrate and harmonize passion and reason, which was at the same time one of the core problems of post- kantian philosophy in germany. what this article shows is that clausewitz developed his idea of reason and passion as potentially opposite human faculties that have to be integrated in some way in his early writings on small wars. this idea was to become highly relevant in the framework of on war, specifically in clausewitz’s trinity of passion, reason and chance and creativity. even though tracing the connections between clausewitz’s conception of small wars and his magnum opus, on war, in a systematic fashion is beyond the limits of this article, it prepares the ground for such an endeavour and provides glimpses of the outcomes that such a study may produce. this article follows paret’s argument that contextualizing clausewitz is crucial to understanding his work. however, contextualizing clausewitz’s writings on small wars and people’s war inevitably distances them from the contemporary strategic context. it implies that clausewitz’s ‘wisdom’ may not indeed be timeless. clausewitz wrote primarily with a view to prussia’s political and strategic situation at the beginning of the nineteenth century, when prussia’s survival was at stake. people’s war, and the inclusion of the people in the defence of their country – their nation – was clausewitz’s solution to prussia’s strategic problems. but a contextual approach to clausewitz’s writings can open up new perspectives on contemporary strategic problems: it prompts us to think, for instance, about the way in which see also jon tetsuro sumida, decoding clausewitz: a new approach to on war (lawrence, ks: university press of kansas, ), pp. ff. sumida recognizes the relevance of small wars for clausewitz’s theory of war; however, he fails to grasp the importance of clausewitz’s engagement with his intellectual context in this respect and claims that clausewitz was a largely idiosyncratic thinker. peter paret, ‘text and context: two paths to clausewitz’, in clausewitz in his time: essays in the cultural and intellectual history of thinking about war (new york: berghahn, ), p. - . reason and passion are integrated in today’s wars in which western states are involved. yet, a contextualization of clausewitz in the methodological tradition of quentin skinner’s approach to intellectual history can only go so far, as it is difficult to discern clausewitz’s ‘intentions’ from his work given that he often seemed to eschew positioning himself intellectually and politically. the alternative, poststructuralist approach to intellectual history as a ‘map of misreadings’ and an iterative and productive process of ‘reading sense’ into classical thinkers through the eyes of the contemporary reader is not a viable methodological option either. if the poststructuralist announcement of the ‘death of the author’ does not consciously call for a selective and self-serving interpretation of clausewitz, at least it offers little hope of being able to avoid the pitfalls of such an approach. the solution to this dilemma consists in constructing a methodological middle ground between skinner’s contextualism and the poststructuralist perspectives associated with barthes, foucault and derrida. this middle ground lies in acknowledging that contemporary readers can analyse clausewitz’s actions (including speech acts) as a soldier, reformer and theorist of war, even though his intentions often remain opaque. it acknowledges both the agency of the historical subject, clausewitz, and the interpreters’ own agency as a historically contextualized individual. put simply, clausewitz was an avid reader and there is evidence that he engaged – intellectually and/or politically – in many debates of his time, but he was not an empty receptacle of others’ ideas or a mouthpiece of any tradition of thought. he absorbed notions and concepts that emerged in his time, but he also transformed them and integrated them into his oeuvre in a partly cf. quentin skinner, ‘meaning and understanding in the history of ideas’, history and theory : ( ), pp. - . more recently skinner, visions of politics, vol. i regarding method (cambridge: cambridge university press, ). cf. graham allen, intertextuality (london: routledge, ), pp. ff. cf. tony burns, ‘interpreting and appropriating texts in the history of political thought: quentin skinner and poststructuralism’, contemporary political theory : ( ), pp. - . idiosyncratic way. what this study seeks to establish is hence not ‘influence’ by, but engagement with his context. the russian linguist mikhail bakhtin’s notion of dialogism is useful in this respect. the dialogical perspective suggests that reading clausewitz’s texts is akin to overhearing a person speaking on the phone: we can only observe one side of the dialogue. the contemporary interpreter of clausewitz’s writings hence possesses agency too, in that s/he actively has to reconstruct the other side of the dialogue. but this agency is not boundless; on the contrary, it is limited. the reconstruction has to make sense against the background of the manifest side of the dialogue as well as against the background of the specific historical context of the dialogue. the remainder of this article proceeds in four steps: the next section introduces clausewitz’s cultural, philosophical and political context as far as this is possible on the basis of his writings, notes and correspondence. it indicates the extent to which clausewitz was exposed, intellectually as well as socially, to the turn of the century philosophical debates. the second part moves on to a reconstruction of what clausewitz referred to as the ‘most beautiful of wars’ – defensive people’s war. it draws upon kantian aesthetics and, in particular, schiller’s aesthetic theory. the third and final section outlines how arguments and themes from clausewitz’s conception of small wars and people’s war stemming from the reform years continued to play a role in the context of his later writings on small wars and people’s war. the conclusion summarizes the article’s main arguments and discusses to what extent clausewitz’s analysis of small wars can be relevant for today’s strategic debates. clausewitz’s cultural, philosophical and political context clausewitz’s early educational background was untypical for the role and status he was to assume later in his life. in , he wrote to his then fiancée (and later wife), marie von brühl: allen ( ), pp. ff. take into account that i am a son of the military camp, the real one, that is, not one from schiller’s poetic world like max piccolomini. […] i could have turned out worse, i grant you that; however, the protection of a diligent education, under the guidance of a worthy friend, could have conferred a purer content upon my background, could have developed my intellectual strengths more thoroughly and could have equipped me with knowledge and an aesthetic education. even though clausewitz is entirely honest about his lack of a formal education in early life, the ease with which he slips in a reference to schiller’s wallenstein illustrates that, at the age of twenty-seven, he was well-studied. the fact that he had eventually found that ‘worthy friend’ in gerhard von scharnhorst, who was clausewitz’s instructor at the allgemeine kriegsschule in berlin between and and became his lifelong mentor, had played a large part in this. scharnhorst imbued clausewitz with a fiercely critical theoretical perspective and an acute sense for the relevance of history to the study of war. johann gottfried kiesewetter, a popularizer of kant’s writings, lectured on logic and mathematics at the allgemeine kriegsschule. clausewitz deepened his study of kant by also attending kiesewetter’s lectures in the pépinière, the prussian academy for army surgeons. the influence of kantian philosophy on clausewitz’s own writings, in particular in the area of his method of reasoning and of the concept of genius, has been widely recognized. marie von brühl, whom clausewitz married in , was another important source of cultural and philosophical education for clausewitz. in , her father, charles karl linnebach (ed.), karl und marie von clausewitz: ein lebensbild in briefen und tagebuchblättern (berlin: verlag martin warneck, ), p. . on clausewitz’s early education see also paret ( ), pp. ff. paret ( ), p. . erich weniger, ‘philosophie und bildung im denken for clausewitz’, in walther hubatsch (ed.), schicksalswege deutscher vergangenheit (düsseldorf: droste verlag, ), p. . e.g. paret ( ), p. ; strachan ( ), pp. ff.; josé fernández vega, ‘war as “art”: aesthetics and politics in clausewitz’s social thinking’, in strachan and herberg-rothe (eds) ( ), pp. - . von brühl, had become the governor of the prussian crown prince, the later frederick william iii. in contrast to carl, marie had enjoyed a diligent education; she spoke french and english fluently and had taken lessons in history and fine arts. in the above-cited letter to marie, clausewitz promised her to catch up on whatever cultural education he may be lacking: ‘wherever you find me wanting, i will soon improve in your proximity and under the influence of your entire noble being’. during his time in paris as a prisoner of war, urged on by marie, he visited picture galleries and studied the paintings of rubens and raffael, but he reported back to his fiancée that his lack of knowledge of the fine arts prevented him from finding immediate intellectual access to them. on another occasion, marie seemed to have urged clausewitz to take up an instrument, to which he replied that he had regretfully no talent at all for music. however, the letters between carl and marie reflect that there was one area in which clausewitz matched his fiancée’s knowledge and enjoyment of the arts: the theatre. it played an important role for the development of their relationship, as the theatre was one of the few places where carl and marie, whose social backgrounds were worlds apart, could meet informally. their correspondence reflects that they had a joint admiration for friedrich schiller’s dramas in particular. schiller is the figure mentioned most often in carl’s letters to marie; clausewitz was familiar with many of his plays, had read his history of the thirty years’ war and cited at least one of his poems. two of schiller’s dramas stand out as apparently particularly significant for both carl and marie: wallenstein and the maid of orleans. in his letters to marie, clausewitz compared himself more than vanya eftimova bellinger, marie von clausewitz: the woman behind the making of on war (oxford: oxford university press, ), pp. ff. linnebach ( ), p. . linnebach ( ), p. . linnebach ( ), p. . marie wrote in her notes on her acquaintance with carl: ‘most often i saw him in the theatre [in der komödie]’; linnebach ( ), p. . see also paret’s preface to the edition of clausewitz and the state, p. xii: ‘clausewitz’s appreciation of the works of schiller deserves further study’. once to the young and idealistic yet tragic figure of max piccolomini from wallenstein. carl proposed to marie on the occasion of their watching together the maid of orleans at least for the second time on may . the topic of both wallenstein and the maid of orleans is war. schiller’s perspective on war was ambivalent, in particular in his wallenstein trilogy, which he completed in . on the one hand, he depicted both wallenstein and the emperor as morally corrupt figures and war itself as a bloody and senseless business. on the other hand – and this must have appealed to the young clausewitz, who knew that rapid advancement through the ranks was his only chance of marrying marie – the figure of max piccolomini embodies the promise of a meritocratic military system and, by extension, a meritocratic and republican society. the maid of orleans, completed in , is less ambivalent about war, even though the disruption of established gender relations, epitomized in the figure of the warrior-woman johanna, indicates that war itself is a deeply disruptive force. and yet, the maid of orleans establishes an analogy between the moral education and empowerment of the individual and the possibility of national catharsis and rebirth. clausewitz, who grew increasingly disheartened and gloomy about the chances of prussia’s revival after the tilsit peace treaty of july , echoed the idea of a national catharsis in a letter to marie from september : ‘but if men have degraded our human nature, then men must be able to ennoble it again; i do not talk of peace and its feeble measures; war opens up a wide field of energetic measures, and if i were to confide in you the most secret thoughts of my soul, i am in favour of the most violent [measures]; i would rouse the languid animal with in he wrote to marie: ‘i have recently reread “wallenstein”. how wonderful, divine, tender and pure are max and thekla!’; linnebach ( ), p. , see also p. . bellinger ( ), p. . elisabeth krimmer, the representation of war in german literature: from to the present (cambridge: cambridge university press, ), p. . krimmer ( ), p. . whiplashes and teach it to break the chains that it allowed itself to be shackled in.’ the idea of war as an educational experience for the individual and a transformative process for the community in the widest sense was not confined to schiller – it was widespread in german literature and philosophy in the early years of the nineteenth century. theodor körner, ernst moritz arndt and heinrich von kleist are seen as paradigmatic examples in this context, as are johann gottlieb fichte’s (more on whom below) addresses to the german nation. but not only romantic authors but also confessed liberals and humanists such as wilhelm von humboldt, whom clausewitz met in berlin around , linked the experience of war to the concept of bildung, education. even kant himself, though most commonly interpreted as a die-hard pacifist owing to his paradigmatic pamphlet on perpetual peace ( ), recognized the sublime quality of war: war itself, if it is carried on with order and with a sacred respect for the rights of citizens, has something sublime in it, and makes the disposition of the people who carry it on thus, only the more sublime, the more numerous are the dangers to which they are exposed, and in respect of which they behave with courage. on the other hand, a long peace generally brings about a predominant commercial spirit, and along with it, low selfishness, cowardice, and effeminacy, and debases the disposition of the people. this is the intellectual context in which clausewitz and his fellow reformers developed their ideas of a people’s war against french occupation. there can be no doubt that clausewitz was not only aware of this context; rather, he engaged with many of its ideas and concepts. he did so in his letters to marie in which aesthetic linnebach ( ), p. . felix saure, ‘agamemnon on the battlefield of leipzig: wilhelm fon humboldt on ancient warriors, modern heroes, and bildung through war’, in elisabeth krimmer and patricia anne simpson (eds) enlightened war: german theories and cultures of warfare from frederick the great to clausewitz (new york: camden house, ), pp. - . immanuel kant, kritik der urteilskraft, werkausgabe vol x (frankfurt a. m.: suhrkamp, [ ]), § . contemplations are interwoven with political comments and military considerations. the importance of late-enlightenment/german idealist aesthetic concepts for the young clausewitz is further highlighted by the fact that he wrote four fragments on aesthetic theory, which paret dates to or . it is thus plausible to argue that aesthetic theory and the expression of political ideals in works of art, and in particular the influence of kant and schiller, provide valuable hints for decoding the young clausewitz’s conception of small wars and people’s war. the ‘most beautiful of wars’ the younger clausewitz was not only an ardent analyst of small wars, he also became a practitioner of small war in the framework of the wars of liberation. in and he lectured at the berlin kriegsschule, the war academy, on the subject of small wars. in his lectures, he referenced eighteenth century classics on petite guerre such as gerhard von scharnhorst ‘pocket manual’ on the subject and the writings of johann von ewald and andreas emmerich. these practitioner- scholars largely treated small wars as a tactical subset of large wars. unsurprisingly, clausewitz himself in his lectures focused on the tactical nature of small wars. however, the eighteenth century context was by no means irrelevant for clausewitz’s further intellectual development. on the contrary, he extrapolated from his analysis of the tactical nature of small wars their strategic potential as ‘Über kunst und kunsttheorie’; ‘Über den begriff des körperlich schönen’; ‘architektonische rhapsodien’, all undated, printed in schering ( ), pp. ff. the essay entitled ‘Über den begriff des körperlich schönen’ reads like a short synopsis of kant’s third critique for clausewitz’s personal use. paret ( ), p. . carl von clausewitz, ‘vorlesungen über den kleinen krieg’, carl von clausewitz: schriften – aufsätze – studien – briefe, vol i, edited by werner hahlweg (göttingen: vandenhoeck & ruprecht, ), pp. - . an english translation has been published recently: clausewitz on small war, edited and translated by james w davis and christopher daase (oxford: oxford university press, ), pp. - . well as their exemplary nature for the study of war as such. smalls wars, he wrote in his lecture script are ‘particularly interesting’ because they require a combination of ‘audacity and caution’ and hence illustrate the ‘free play of the spirit [geist]’ – a notion to which clausewitz returned in his famous trinity in book i, chapter one of on war. as a member of the prussian reform movement, clausewitz also played a central part in the plans for a popular insurrection against napoleon’s occupation of prussia. in his letters to gneisenau between and clausewitz reviewed various options to leave prussia in order to fight against napoleon. in september clausewitz submitted a plan for ‘operations in silesia’ to gneisenau, for which neither of them had official backing at the time. between and gneisenau himself, as well as clausewitz’s mentor gerhard von scharnhorst, worked on plans for a popular insurrection against french occupation, plans that were in explicit breach of the terms of the peace treaty of tilsit. as is well clausewitz, ‘vorlesungen über den kleinen krieg’, p. . the notion of the ‘free play’ of the spirit or of all human faculties first appeared in gotthold ephraim lessing’s laokoon (stuttgart: reclam, [ ]), p. . kant ( [ ]), § , also used it in the critique of judgment. for both lessing and kant the ‘free play’ indicated that the experience of beauty had to transcend the level of sensual perception and had to engage reason. hence lessing’s and kant’s aesthetics were fundamentally rationalist. for schiller, sensibility and reason had to be engaged in equal measure in the experience of beauty in order to realize the ideal of freedom. frederick beiser, schiller as philosopher: a re-examination (oxford: oxford university press, ), pp. f. e.g. letter from clausewitz to gneisenau from january , printed in carl von clausewitz, schriften – aufsätze – studien – briefe vol i, edited by hahlweg, p. . letter from clausewitz to gneisenau from september , printed in hahlweg ( ), p. ff. august neidhardt von gneisenau, denkschriften zum volksaufstand von und , edited by harald von koenigswald (berlin: junker und dünnhaupt, ); gerhard von scharnhorst, private und dienstliche schriften, vol v, edited by michael known, clausewitz left prussian service on april in order to join the russian forces fighting against napoleon. he joined the russo-german legion, which effectively fought as an auxiliary force to the regular russian army, and served as its chief of staff. in february clausewitz and his fellow reformers yorck and dohna gave orders to raise an east prussian landwehr after yorck had signed the convention of tauroggen which ended the franco-prussian alliance – both without the consent of the king. the most notable of the texts that clausewitz wrote in the years to is his bekenntnisdenkschrift of february . this document was not intended for immediate publication; instead, clausewitz only circulated it among some of his friends and fellow prussian reformers. clausewitz’s theory of war has often been described as battle-centric; however, in the text, he presented battle in a light that is very different from the central relevance that battle holds in on war. the mobilization and unification of all insurrectionary forces, clausewitz wrote, could turn the tide of victory against the french occupation forces, thereby becoming more decisive than the ‘dubious fortune of battles’. in his plans for the mobilization of landwehr (militia) and landsturm (insurrection) forces, he made it sikora (hamburg: böhlau, ), p. . gneisenau’s memorandum on the landsturm, which he and scharnhorst jointly submitted to the prussian chancellor karl august von hardenberg, served as the template for the landsturmedikt. in the landsturmedikt, the prussian king sanctioned the organization of a popular insurrection against the napoleonic forces. however, the edict was never implemented and was weakened to the point of suspension by a revision of july . ‘bekenntnisdenkschrift’, printed in hahlweg ( ), pp. ff – i am using my own translations of the german edition, since paret and moran unfortunately did not include the full text of the bekenntnisdenkschrift in their edition of clausewitz’s historical and political writings. ‘but since the essence of war is fighting, and since the battle is the fight of the main force, the battle must always be considered as the true center of gravity of the war.’ on war, book iv, ch. , p. [vom kriege, p. ]. ‘bekenntnisdenkschrift’, p. – emphasis added. clear that these forces were not intended as a mere reserve for the regular army. rather, he explicitly argued that they should stay away from any major engagements. their role was supposed to be modelled on the historical examples of the popular uprisings in the tyrol, spain and the vendée, meaning that they were intended to cut off the opponent from his supplies and prevent him from requisitioning resources from the local population. in such a role, clausewitz argued, the landsturm would be a ‘terrifying force’ and it would be ‘decisive’: ‘a general cause becomes prevalent and the skill, power and greatness of the individual man [napoleon, presumably] is shattered like a small skiff by the furious waves of the stormy sea.’ in this situation, the occupying power would find itself fighting ‘this most unfortunate [unglükseeligste] of wars’. in his letter to the german philosopher johann gottlieb fichte of january , clausewitz had matched the notion of the ‘most unfortunate of wars’, viewed from the perspective of the occupying power, with the term of the ‘most beautiful of wars’, which described the perspective of the defending side in a people’s war. he explained that ‘the most beautiful of wars’ was a war ‘in which a people fights on its own territory for its freedom and independence’. clausewitz’s letter referred to an article that fichte had published in entitled ‘machiavelli’. clausewitz criticized machiavelli and, by extension, fichte’s take on machiavelli, for trying to revert back to classical forms of warfare, whereas clausewitz himself argued that reviving the classical spirit was what was needed. he explained: the modern art of war, far from using men as simple machines, must vitalize their energies as far as the nature of its weapons permits. there are of course limits to this, as it is an indispensable requirement for mass armies that a sensible will can lead them without too much friction [reibung]. ‘bekenntnisdenkschrift’, pp. ff – emphasis added. ‘bekenntnisdenkschrift’, p. . ‘bekenntnisdenkschrift’, p. – emphasis added. ‘ein ungenannter militär an fichte’, printed in schering ( ), p. – emphasis added. again i am using my own translation in order to avoid some inaccuracies in paret’s and moran’s edition. ‘ein ungenannter militär an fichte’, p. . but this should be the natural limit, and one should not, as was the tendency in the eighteenth century, try to form the whole into an artificial machine, in which the moral forces are subordinate to the mechanical forces, the effect of which is achieved through a simple mechanism, which are supposed to defeat the enemy through mere forms, and in which the individual is given the smallest task for the use of its intellectual forces. the history of all citizens’ wars [bürgerliche kriege], and in particular the swiss war of independence and the french revolutionary war, demonstrate that one can achieve infinitely more by vitalizing individual energies than by relying on artificial forms. in this context, victory is presented as the result of the moral and intellectual strengths of the individual. that the individual and not the collective is the starting point of a potential political rebirth of prussia (and, in fact, possibly of germany and the whole of europe) is a thought that clausewitz had developed early. in , he wrote to marie from the cantonment in the county of mansfeld: ‘the troops that are passing by give a truly aesthetic impression, but one that is quite different from our military parades. while the latter display rigid formations, here you can clearly discern the individual in all its singularity in the open ranks, and the steady movement of the procession coexists with diversity and the full expression of life.’ the notion of individuality would later recur in his lectures on small war, even though in the context of those lectures it had a merely tactical meaning: ‘the individual hussar and jäger has an enterprising spirit, a confidence in himself and his luck that is barely known to him who always served in the line.’ in his concept of people’s war, clausewitz effectively fused the tactical capacity of the individual in small wars with the transformative potential in aesthetic-moral terms of people’s war. ‘ein ungenannter militär an fichte’, pp. ff. linnebach ( ), p. ; emphasis added. the idea that the moral qualities of the individual were corrupted by machine-like drill and discipline can also be found in kleist and w. v. humboldt; see paret, ‘a learned officer among others’, paret ( ), p. ; saure ( ), p. . clausewitz, ‘vorlesungen über den kleinen krieg’, pp. f. on this fusion see in more detail heuser ( ), pp. - . it was from the perspective of the centrality of the individual that clausewitz took issue with the argument fichte put forward in his machiavelli text: faced with the dilemma of how to free the individual from the shackles of a corrupted political system and society, fichte’s position after vacillated between ‘conscious, collective, transformative action’ on the one hand and the ‘imposition of constraint in order to raise individuals to the practice of virtue’ on the other. the latter was the gist of the machiavelli text. fichte believed that the warrior ethos instilled by the modalities of ancient warfare was an important potential source of such virtue. clausewitz disagreed: surely in ancient times the value of the individual warrior was generated more by their civic constitution [bürgerliche verfassung] than their way of fighting, which is even more undeniable given that those peoples who proved themselves in war differed from the defeated with respect to their civic constitution rather than their being accustomed to personal combat. against fichte, clausewitz emphasized the transformative potential of the individual. he acknowledged the potentially vicious circle consisting of a corrupted political system that suppressed the moral qualities of its individuals, hence making it difficult for individuals to unfold their full potential. however, the ‘most beautiful of wars’ appeared to be the way out of this conundrum. what did clausewitz mean by the phrase ‘the most beautiful of wars’? in his writings, he never ceased to emphasize the cruelty of war, the violence and the destruction – in fact, he repeatedly exhorted his readers to face up to the gruesome realities of mass warfare. so surely clausewitz did not think that people’s war, which he saw as particularly atrocious, was an uplifting or aesthetically pleasing spectacle. the answer to this puzzle lies in clausewitz’s reception of the aesthetic writings of his time, and in particular those of kant and schiller. douglas moggach, ‘fichte’s engagement with machiavelli’, history of political thought, : ( ), p. . ‘ein ungenannter militär an fichte’, pp. ff. ‘bekenntnisdenkschrift’, p. . kant wrote his third critique not with a view to founding an aesthetic theory in the sense of a theory of art, but to close a gap in his epistemology. according to kant, knowledge based on experiences involves three faculties: sensibility, imagination, and understanding. the third of these faculties, understanding, allows the human mind to sort its experiences according to rational concepts. the characteristic feature of the aesthetic experience, according to kant, is that it initiates a process in which sensibility and understanding enter into a ‘free play’ of ‘harmonious activity’ in which neither gains the upper hand, as it were, but one furthers the other and vice versa. this evidently indicates that rationality – understanding – plays a central part in the aesthetic experience, but it is not its ultimate arbiter. the process is an infinite one, meaning that the mind never arrives at a ‘concept’, at an ultimate interpretation. kant’s idea of beauty comprises a number of features: beauty is a concrete experience; it is sensual without being linked to immediate interests (such as appetite or sexual desire); the experience of beauty is inherently social as the judgment of taste is universal even though it cannot be subsumed under a rational concept; finally, the experience of beauty has a vitalizing effect on all human faculties, in as much as they enter into a free play of harmonious activity. most importantly, however, for kant, ‘the beautiful is the symbol of the morally good’. the concept of morality inhabits the realm of rationality, but it cannot be experienced through the senses. moral notions such as freedom can be derived in a rational way, but they lack empirical demonstrability. in this sense, the experience of beauty is the counterpart of the concept of morality: the first is empirical without ever arriving at a rational concept, the second is conceptual, but devoid of empirical content. against this background, clausewitz’s notion of the ‘most beautiful of wars’ makes more sense: what it hints at is the moral value or character that a people’s war against french occupation had in clausewitz’s eyes. such an interpretation gains kant ( [ ]), § . kant ( [ ]), § . additional plausibility when we take into account clausewitz’s closing statement in his letter to fichte, where he wrote that he believed that people’s war ‘will overcome any other art of war, however perfect a product of reason the latter may be, not to mention that it [people’s war] would according to its nature come closest to the most perfect form [ihrer natur nach sich der vollkommensten form am meisten nähern würde].’ ‘freedom’ is the next central term that defines the ‘most beautiful of wars’. as we have seen above, such a war is defined as one being fought by a people ‘on its own territory for its freedom and independence’. this is where schiller’s aesthetics come into play. in his aesthetic letters, schiller wrote that ‘beauty is the only possible expression of freedom in appearance’. schiller built on kantian aesthetic theory, which had already emphasized the link between beauty and freedom. this link existed both in the sense that the experience of beauty liberated the individual from desire and in the sense that beauty was a symbol of the morally good, in the framework of which, in turn, freedom played a central role. in the context of schiller’s philosophy, beauty and art became the centrepiece of his emancipatory project. schiller and clausewitz, and fichte, for that matter, shared some core convictions: they deplored the moral and political weakness of prussia and the hopeless situation of germany in the face of french expansion ‘ein ungenannter militär an fichte’, pp. ff. here clausewitz follows schiller’s argument of beauty as a regulative ideal that can only be reached through the integration of reason and sensibility. note also that a parallel idea reccurred later in book viii, ch. b of on war in which clausewitz depicted the french revolutionary and napoleonic wars and the resistance against them as instances in which war ‘rather closely approached its true character, its absolute perfection’; on war, book viii, ch. b, p. [vom kriege, ]. ‘ein ungenannter militär an fichte’, p. - emphasis added. friedrich schiller, on the aesthetic education of man, translated by reginald snell (mineola, ny: dover, ), letter – emphasis added. kai hammermeister, the german aesthetic tradition (cambridge: cambridge university press, ), p. . more broadly and they emphasized the need to overcome this situation through education. schiller’s diagnosis of the political and social ills of his times was twofold: the upper strata of society were ‘overrefined’ and, as a result, suffered from languor and permissiveness and a general lack of energy and vitality. this is a charge that clausewitz too made in the bekenntnisdenkschrift, where he argued that prussia’s political elites masked their fears as rational decisions and, as a result, became paralysed and incapable of action: reason alone is supposed to decide, everyone demands. as if fear weren’t an expression of the mind [gemüth – more emotional than rational], as if it would allow for a free judgement of reason. all that can be granted is that both confessions of faith, that in favour of resistance and that in favour of subservience, emanate equally from the mind [gemüth], but that the first is fuelled by courage, whereas the second is fuelled by fear. fear paralyses reason, whereas courage energizes it. if schiller, who wrote his aesthetic letters under the impression of the reign of terror in revolutionary france, did not appreciate the decadence of the ruling classes, he did not have much trust in the moral resources of the people either. whereas the elites were given to decadence, he argued, the ‘numerous classes’, if let loose, displayed ‘barbarity’. the central question for schiller, then, was how to break out of the vicious circle of the corruption of the state and its elites on the one hand and the lack of education of society, which stifled the attainment of freedom by the individual, on the other. schiller’s solution consisted in the idea of the ‘aesthetic state’, a political collective that comes into existence once human beings have transformed themselves into holistic individuals through aesthetic education: ‘the aesthetic state alone regards us as whole beings, as both rational and sensible, because we participate in social life from inclination rather than duty. […] only in beauty do we bring together both universal and individual, the will of the whole and the nature of the individual.’ schiller, on the aesthetic education, letter ; cf. hammermeister ( ), p. . ‘bekenntnisdenkschrift’, p. . schiller, on the aesthetic education, letter . beiser ( ), p. . it was fichte who pointed out the essential weakness of schiller’s ideas, in an article entitled ‘ueber geist und buchstab in der philosophie’ (‘on the spirit and the letter in philosophy’) that fichte submitted in to the journal that schiller edited, entitled die horen: [i]f it is on the one hand not advisable to give freedom to man before his aesthetic sense is developed, it is on the other hand impossible to develop the latter before he is free; and the idea to lead man to the appreciation of freedom through aesthetic education and hence to freedom itself gets us into a vicious circle unless we find a means beforehand of awakening the courage in some individuals out of the great multitude to be nobody’s master and nobody’s slave. unsurprisingly, schiller refused to publish fichte’s article. clausewitz was not convinced by schiller’s aesthetic utopia either: a nation cannot break free from the slavery of foreign domination through the arts and sciences. it has to throw itself into the ferocious element of fighting [ins wilde element des kampfes]; to gamble a thousand lives for the thousand-fold gain of life. only thus can it rise from the sickbed to which foreign bonds had shackled it. in other words, for clausewitz fighting was the way out of the vicious circle of the corruption of state and society on the one hand and the lack of individual moral qualities on the other. in this context, clausewitz, then, remained true to his combat-centric perspective on war, but he harnessed his belief in the centrality of combat to his views on the possibility of political emancipation. this is not to say that clausewitz did not realize the chicken and egg problem that fichte and schiller were grappling with. in the bekenntnisdenkschrift, in which he often weighed his arguments against possible counter-arguments, he considered that the government may have to give the first impetus to a general insurrection, should the people not take up arms on their own account: ‘there is a form of coercion, and even terrible coercion, which is not tyranny.’ and yet, his trust in the emancipatory spirit of the people re-asserted itself just a few lines below: ‘nothing fichte quoted in hammermeister ( ), p. . ‘vergleich zwischen den europäischen staaten’, printed in schering ( ), p. – emphasis added. is as true as that extraordinary adversity, once man decides to confront it with extraordinary means and to focus all his forces against it, conduce him to rise above himself and excite the forces of the mind [gemüth] and reason of which he himself was not aware.’ the free play of passion and reason, which was at the heart of schiller’s idea of freedom, enabled clausewitz’s individual to rise above all internal and external constraints. in contrast to both fichte and schiller, however, clausewitz evidently did not fear that a sudden empowerment of the people could unleash forces that would inevitably turn against the emancipatory project. such concern was common in german literary and philosophical circles around . it found its probably most famous expression in goethe’s exclamation at the end of the sorcerer’s apprentice ‘from the spirits that i called/sir, deliver me!’ clausewitz, on the contrary, anticipated a general insurrection to be met with particularly cruel and ferocious measures by the french (he had studied the war in the vendée and the peninsular war, after all) and exhorted his fellow prussians to outbid the cruelty of napoleon’s forces: ‘let us take our chances at paying back atrocity with atrocity, at reciprocating cruelty for cruelty! it will be easy for us to outbid the enemy and to lead him back into the boundaries of restraint and humanity.’ traces of clausewitz’s early writings on people’s war can still be found in on war. in book vi, chapter , the chapter on ‘people’s war’, clausewitz wrote: no matter how small and weak a state may be in comparison with its enemy, it must not forego these last efforts [popular insurrection], or one would conclude that its soul is dead. […] a government that after having lost a major battle, is only interested in letting its people go back to sleep in peace as soon as possible, and, overwhelmed by feelings of failure and disappointment, lacks the courage and desire to put forth a final effort, is, because of its weakness, involved in a major inconsistency in any case. it shows that it did not deserve to win, and, possibly for that very reason was unable to. ‘bekenntnisdenkschrift’, p. . ‘bekenntnisdenkschrift’, p. . on war, book vi, chapter , p. [vom kriege, pp. f]. absolutism was the heyday of body metaphors and body politics, as the seminal studies of kantorowicz, elias and foucault have shown. the state was imagined as a body, personified in the absolutist ruler, who was also often depicted as its soul, mind or spirit that animated his or her subjects. clausewitz attributed this animating function, the image of the soul, to the people. but the notion of the soul also played a role in the framework of german aesthetic theory. one of the first attempts to push beyond the cartesian dualism of the body and the soul was made by julien offray de la mettrie in his essay entitled ‘l’homme machine’. in this essay, de la mettrie imagined the human body as some kind of mechanical clockwork and the soul as its – equally mechanic – extension. in his essay anmut und würde [grace and dignity] schiller aimed to de-mechanize the soul while at the same time retaining its synthetic connection with the body: grace is physical beauty in motion, animated by the soul. there are echoes of this anti- mechanistic impetus in clausewitz’s letter to fichte, where he repeatedly pitched the moral forces of the individual against the mechanical, over-rationalized machine-like tendencies of eighteenth century military organization. however, since schiller’s aesthetic theory is inherently a theory of morality, the significance of the soul for schiller went further. in anmut und würde he introduced the notion of the ‘beautiful soul’. the term stemmed initially from the context of german pietism – a tradition that clausewitz was probably familiar with from his childhood years. for schiller, ‘a beautiful soul is someone who does their duty from inclination, who acts on the moral law with joy. schiller describes jeffrey merrick, ‘the body politics of french absolutism’, in sara e. melzer and kathryn norberg (eds) from the royal to the republican body: incorporating the political in seventeenth and eighteenth century france (berkeley, ca: university of california press, ), p. . jane v. curran, ‘bodily grace and consciousness: from the enlightenment to romanticism’, in marianne henn and holger a. pausch (eds) body dialectics in the age of goethe (amsterdam: rodopi, ), p. . ‘ein ungenannter militär an fichte’, pp. ff. paret ( ), p. . the beautiful soul as a person who acts with complete freedom, and therefore without the constraint of sensibility or the moral law.’ the beautiful soul for schiller possessed virtue in the sense of a natural disposition to act according to the moral principle. in this context, schiller further developed kantian ethics based on principle and law and introduced the notion of virtue in a bid to render the reconciliation of passion and reason, which according to kant only occurred during the experience of beauty, more sustainable in time. this idea resonates deeply with clausewitz’s notion of passion and reason, in particular as he represented it in his letter to fichte, where he continued to emphasize that passion and reason have to be integrated in order to enable both victory in the ‘most beautiful of wars’ and the emancipation of the individual. it is not surprising that he ended his letter with the speculation that warrior virtue could be partly instilled by good military leadership, but had to rely on the primordial moral qualities of the individual in the first place. small wars and people’s war after the reform years clausewitz’s concept of people’s war is an eminently political one. this resonates with recent research that has shown that clausewitz did not develop the idea of war as a political act late in the process of writing on war. on the contrary, the political character of war was an element of clausewitz’s thinking that evolved from his earliest writings, in particular those on people’s war. of specific importance in this respect is the relationship between passion and reason. ‘the beiser ( ), pp. ff. for goethe’s and hegel’s critique of the notion of the ‘beautiful soul’ see david ellison, ethics and aesthetics in european modernist literature: from the sublime to the uncanny (cambridge: cambridge university press, ), pp. ff. ‘ein ungenannter militär an fichte’, p. . of course, the notion of virtue also refers to machiavelli in this context. anders palmgren, visions of strategy: following clausewitz’s train of thought (phd thesis, helsinki: national defence university, ). most beautiful of wars’ requires the integration of the dichotomy between passion and reason – a thought that clausewitz developed in an intellectual ‘dialogue’ with the german aesthetic discourse around . passion is not something that needs to be suppressed in order to enable military effectiveness and political freedom; on the contrary, passion is an integral part of both. without passion, the soul is dead, and the rational capacities of men become formalistic and idle. the integration of passion and reason is also what makes war so eminently political; in other words, what enables war to transform the political realm: ‘where policy is pitted against passion, where hostility ousts rationality, the characteristics of war itself can subordinate usurp those of the “trinity” [of passion, reason and creativity].’ the integration of passion and reason is central to clausewitz’s thought, and it continued to play a crucial role in his later writings. even his essay entitled umtriebe, written in the early s and according to paret ‘the most puzzling of all of clausewitz’s works’, reflects the essential gist of clausewitz’s conception of people’s war. as moran explained in his introduction to the text, umtriebe was written at a time when clausewitz hoped for an appointment as prussian ambassador to great britain, and was hence at pains to distance himself from the revolutionary agitations of individuals such as karl sand, who had murdered the conservative august von kotzebue in march , and from the broader national revolutionary movement in germany more generally. according to clausewitz, the root cause of these revolutionary agitations were the ideas put forward by ‘scholars and philosophers’: ‘these people [the agitators] were strongly taken with the philosophy and politics of paris, and the majority aron comes closest to acknowledging the reciprocal relationship between passion and reason, but zweckrationalität, instrumentality, trumps the equivalence between the two elements; raymond aron, ‘reason, passion and power in the thought of clausewitz’, social research : ( ), pp. - . see also strachan ( ), pp. ff. strachan ( ), p. . paret ( ), p. . moran in paret and moran ( ), pp. ff. cf. paret ( ), p. . threw themselves into the maelstrom of revolutionary ideas in a wholly different way [than the majority of the people – die große masse des volkes]. in this scenario, reason and passion are out of balance. the older clausewitz became increasingly aware of the pitfalls of demagoguery and the danger that intellectual elites and interest groups could whip up the passions of the masses with the help of ideas that the latter were unable to grasp. clausewitz’s lifelong ambivalence towards parliamentary democracy was rooted in these concerns. for clausewitz, the involvement of the people in the defence of their country, be it in the framework of people’s war or in the framework of a popular militia, the landwehr, were the central institutions of a reformed prussian state and society. clausewitz never ceased to defend the landwehr against its – increasingly numerous and influential – detractors. in two essays, entitled ‘our military institutions’ and ‘on the political advantages and disadvantages of the prussian landwehr’, his belief in popular participation in war and the defence of the nation as a substitute for parliamentary democracy is fully evolved: but the moral power of the landwehr also affects the way people live. when all state institutions are organized around an armed landwehr, when all the state’s energies are directed towards it, when all officals, high and low, are instructed to treat this institution, which in principle knows no bounds, as an expression of the absolute power of the nation, then any direction imparted to it from above will produce entirely different results than if everything remained confined within an institution divorced from the people themselves. here, clausewitz depicted the landwehr as the only viable expression of popular sovereignty. in contrast to participatory democratic institutions, clausewitz argued, the landwehr fostered unity, not division; in fact, it could even be used in order to keep revolutionary factionalism in check: with this institution let the government mobilize the energies of a valiant people against its external enemies and rivals; with this institution let the government ‘umtriebe’, printed in carl von clausewitz: politische schriften und briefe, edited by hans rothfels (münchen: drei masken verlag, ), , – my translation. ‘our military institutions, printed in paret and moran ( ), p. – emphasis added. enchain reckless forces if they turn against their own community in frenzy and ferment. finally, these arguments are also in line with clausewitz’s perspective on the polish question, which he elaborated in two essays in , ‘europe since the polish partitions’ and ‘on the basic question of germany’s existence’. both essays have been interpreted as proof of the mature clausewitz’s turn to political realism. it is true that clausewitz framed his arguments against poland’s restoration in terms of balance-of-power considerations and expressed the fear that a liberated poland would ally itself with france. however, this did not signify a turn away from his earlier political convictions. for clausewitz, the polish rebellion of - was not a self-defensive people’s war, not a ‘beautiful war’, in other words, because the poles were not a nation (an argument he also made, to a lesser extent, with respect to belgium and italy). he denounced the poles as a ‘very able people, but one that for centuries has remained half-tartar in the midst of civilized european states’. for twenty-first century readers, this reads like a racist slant. it is definitely orientalist, in that it pits the poles against the supposedly more civilized european states. it is also true that clausewitz did not like the poles, but his reference to their ‘tartar’ habits probably did not aim at their racial origin, but at their irregular way of fighting, which linked them to the eighteenth century partisan warfare tradition. ‘the prussian landwehr’, printed in paret and moran ( ), p. . also printed as ‘Über die politischen vorteile und nachteile der preussischen landwehr’, geist und tat, pp. - . paret ( ), p. . cf. paret ( ), pp. ff. ‘germany’s existence’, printed in paret and moran ( ), p. . in his ‘der krieg der russen gegen die türken von - ’ clausewitz discussed the irregular tactics that the crimean tartars used against russian forces; hinterlassene werke des generals von clausewitz, vol x (berlin: dümmler, ), pp. ff.. tartars also feature in book ii, chapter , of on war alongside ‘cossacks and croats’, which once again indicates a tactical – as opposed to a racial – understanding of the term. on war, book ii, ch. , p. [vom kriege, p. ]. in his broad-brushed overview of the historical development of war in book viii, clausewitz, having lectured on ‘small wars’ at the allgemeine kriegsschule in and , was of course familiar this tradition. while clausewitz perceived it as an illustration of the tactical potential of people’s war, he became increasingly concerned about instances in which partisan warfare emerged in the context of people’s war, as had happened, for instance, with the emergence in of lützow’s free corps. ‘lützow’s unruly volunteers’, as clausewitz referred to them in umtriebe, had been a pan-german unit of volunteers authorized by scharnhorst. the free corps had the reputation of being mainly composed of students and academics, and a number of them became leading figures in the national revolutionary movement after the war. for clausewitz, these were precisely those intellectuals who were misguided by ‘revolutionary ideas’ that did not have any connection to the masses of the people. in other words, nineteenth century partisan warfare was no longer a mere tactical complement to regular warfare, as it had been in the eighteenth century; rather, it was an ideologically driven form of war conducted by intellectual elites that threatened to undermine the unity and strength,- the ‘beauty’- of people’s war. and this is precisely the charge that clausewitz levelled against the polish rebellion: it was not a people’s war, not a war of national self-defence, but a brainchild of ‘the political philosophers of our day [who] wish to reform the process of national development’. once again, the relationship between reason and passion was upset, in that reason – revolutionary ideas and ideologies – tried to harness chapter b, tartars feature as an example of a war-like people who were, even though they are ‘semibarbarous’, militarily highly proficient. on war, book viii, ch. b, p. [vom kriege, p. ]. in the tartars’ wars, the war-like element (primordial violence) manifested itself in a particularly unrestrained way; however, this was not owing to their semibarbarous character. rather, it was a function of the identity of popular passion and political aim, which could also occur among ‘civilized’ peoples – e.g. in the framework of popular insurrections. cf. palmgren, visions of strategy, p. . ‘agitation’, printed in paret and moran ( ), p. . see also heuser ( ). ‘agitation’, paret and moran ( ), p. . ‘europe since the polish partitions’, printed in paret and moran ( ), p. . popular passion to its idiosyncratic aims which were neither connected to realpolitik nor to the needs of the people. even though clausewitz grew increasingly aware of the danger that demagogues could try to harness the idea and the passion of people’s war to their own revolutionary and factionalist motivations, his basic convictions on the empowerment of the people in the framework of national self-defence did not change over time. conclusion this article has argued that clausewitz in his writings between and sketched out an eminently political understanding of war, in which people’s war, which he referred to as the ‘most beautiful of wars’, possessed inherently liberating qualities. clausewitz exhorted his fellow prussians to engage in people’s war not only in order to rid prussia of the yoke of napoleonic domination, but also to liberate its citizens from the corruption of the prussian late-absolutist monarchy. the ‘most beautiful of wars’, understood as a moral war, hence unified and integrated the instrumental quality of war as a liberation from foreign domination on the one hand and the existential quality of war as an emancipation of the individual through the experience of combat and the concomitant revelation of its inherent moral capacities. the acknowledgment of the existential aspect of war, combat and violence and its immediate political significance, both for the internal coherence of a nation and for the external power of a state, is a thought that clausewitz took most likely from his mentor scharnhorst. clausewitz’s original contribution consisted in putting this idea on a philosophical basis, the main ingredients of which he developed in the framework of a ‘dialogue’ with the german aesthetic discourse around , in particular kant’s and schiller’s aesthetic theories. clausewitz largely followed schiller’s aesthetic theory in its attempt to integrate reason and passion, and this gerhard von scharnhorst, private und dienstliche schriften, vol ii: stabschef und reformer (kurhannover - ), edited by johannes kunisch (berlin: de gruyter, ), aufzeichnung , p. . integration formed a core element of his concept of people’s war. in on war, this dichotomy was broadened to the ‘wondrous trinity’, ‘composed of primordial violence, hatred, and enmity’, ‘of the play of chance and probability in which the creative spirit is free to roam [freie seelentätigkeit]; and of its element of subordination, as an instrument of policy, which makes it subject to reason alone’. the notion of ‘freie seelentätigkeit’ itself is a reincarnation of the ‘freie spiel des geistes’, a notion that clausewitz had already used in / to describe the characteristic feature of small wars. finally, the way in which clausewitz, in analogy to schiller’s aesthetics, used the notion of the ‘most beautiful of wars’ as a regulative ideal, something that approaches the ‘most perfect form’ of war recurred in the notion of ‘absolute war’ in book viii of on war, when clausewitz described the era of the french revolutionary and napoleonic wars as a time in which war had reached a ‘state of absolute perfection’. reconstructing clausewitz’s writings against the backdrop of his intellectual and political context highlights that his conception of small wars does not provide a timeless ‘wisdom’ that can be applied to twenty-first century problems. the strategic context in which he lived and which he analysed is about as far removed from the strategic context of western states today as it could be. most european countries – the current exception being the baltic states and eastern europe – are surrounded by friends. moreover, after almost two centuries of mass conscription (again, there are exceptions) most western states have turned away from conscription and the ideal of the citizen-soldier as the foundation of their national and collective defence. the increasing professionalization of western armed forces is the flipside of the abolition of conscription. however, clausewitz asked a pertinent question, and one that is today probably more relevant than ever: how to integrate reason and passion in politics and war. for clausewitz, the first step to achieve this integration was the involvement of the on war, book i, ch. , p. [vom kriege, p. ]. on war, book viii, ch. , p. [vom kriege, p. ]. anthony king, the transformation of europe’s armed forces: from the rhine to afghanistan (cambridge: cambridge university press, ). people in the defence of their own country. clausewitz was right in assuming that the nationalization of war that had started with the french revolution was to transform war in europe for a long time and that it was deeply entangled with political transformations and the democratization of war and politics. conversely, the increasing professionalization of western armed forces will require a new balance or a new alignment in the relationship between reason and passion in war. today’s debates in strategic studies indicate that clausewitz’s question is still of central importance: from the debate over ‘post-heroic’ societies and the lament over the decline in republican virtues to the observation that western wars today are essentially conducted ‘without the people’, there is a sense that reason and passion are again out of balance. clausewitz’s conception of small wars and people’s war focuses the mind on this issue, even though the answers he gave reflect his early nineteenth-century context and cannot be readily applied to the twenty-first century. acknowledgements i would like to thank hew strachan, antulio j echevarria ii, isabelle duyvesteyn and fred beiser for taking the time to discuss the tentative beginnings of this paper. i am also grateful to the three anonymous reviewers for their comments and guidance. cf. sibylle scheipers (ed.) heroism and the changing character of war: toward post-heroic warfare (basingstoke: palgrave macmillan, ), pascal vennesson, ‘war without the people’, in hew strachan and sibylle scheipers (eds.) the changing character of war (oxford: oxford university press, ), pp. - . evp .. article on the borders of harmful and helpful beauty biases: the biasing effects of physical attractiveness depend on sex and ethnicity maria agthe , maria strobel , matthias spörrle , michaela pfundmair , and jon k. maner abstract research with european caucasian samples demonstrates that attractiveness-based biases in social evaluation depend on the constellation of the sex of the evaluator and the sex of the target: whereas people generally show positive biases toward attractive opposite-sex persons, they show less positive or even negative biases toward attractive same-sex persons. by examining these biases both within and between different ethnicities, the current studies provide new evidence for both the generalizability and the specificity of these attractiveness-based social perception biases. examining within-ethnicity effects, study is the first to demonstrate that samples from diverse ethnic backgrounds parallel the finding of european caucasian samples: the advantageous or adverse effects of attractiveness depend on the gender constellation of the evaluator and the evaluated person. examining between-ethnicity effects, study found that these attractiveness-based biases emerge almost exclusively toward targets of the evaluator’s own ethnic background; these biases were reduced or eliminated for cross-ethnicity evaluations and interaction intentions. we discuss these findings in light of evolutionary principles and reflect on potential interactions between culture and evolved cognitive mechanisms. keywords physical attractiveness, cognitive bias, biological sex, ethnicity, social evaluation date received: november , ; accepted: may , imagine a manager evaluating a very attractive job applicant. would the candidate’s attractiveness give him or her an advan- tage in the job selection process? most of the extant literature provides a clear answer to this question: yes, it would. attrac- tiveness has been shown to exert powerful positive effects on social evaluation and decision-making (langlois et al., ; lemay, clark, & greenberg, ). however, recent research suggests that the manager’s reac- tion to the candidate’s attractiveness might depend on whether or not the manager and candidate are of the same sex. although people tend to positively evaluate attractive members of the opposite sex, the same does not always hold true for evalua- tions of the same sex. indeed, people often see attractive mem- bers of their own sex as a threat—both to their self-esteem and to their relationships and reproductive success (gutierres, ken- rick, & partch, ). from an evolutionary perspective, attractive same-sex persons may be perceived as rivals (bleske & shackelford, ; buss, , , ; maner, gailliot, rouby, & miller, ), so that people might sometimes react negatively to them (buss & dedden, ; buss, shackelford, department of psychology, ludwig maximilians university of munich, munich, germany technical university of munich (tum), munich, germany university seeburg castle (usc), seekirchen, austria ludwig maximilians university of munich, munich, germany kellogg school of management, northwestern university, evanston, il, usa corresponding author: maria agthe, department of psychology, ludwig maximilians university of munich, munich , germany. email: mariaagthe@lmu.de evolutionary psychology april-june : – ª the author(s) reprints and permissions: sagepub.com/journalspermissions.nav doi: . / evp.sagepub.com creative commons cc-by-nc: this article is distributed under the terms of the creative commons attribution-noncommercial . license (http://www.creativecommons.org/licenses/by-nc/ . /) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the sage and open access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage). mailto:mariaagthe@lmu.de http://www.sagepub.com/journalspermissions.nav http://evp.sagepub.com choe, buunk, & dijksta, ; schmitt & buss, ; vail- lancourt, ). consequently, the manager might be inclined to derogate an attractive same-sex applicant (agthe, spörrle, & maner, ). but now imagine that the attractive same-sex candidate and the manager are of different ethnic groups. would the manager still derogate the attractive same-sex applicant? or, instead, might differences in their ethnicities change their social schema such that the applicant is no longer perceived as a threat? in the current article, we demonstrate that whether someone is evaluating an individual of the same versus a dif- ferent ethnicity plays a critical role in whether attractiveness affects social judgment and decision-making. examining the moderating effects of ethnicity provides a fruitful opportunity to investigate both the generalizability and the specificity of attractiveness-based social evaluation biases. positive and negative effects of attractiveness on social evaluation across cultures, attractive persons receive favorable interper- sonal evaluations (chen, shaffer, & wu, ; shaffer, cre- paz, & sun, ; wheeler & kim, ). such evaluations reflect people’s desire to interact with good-looking persons because they represent social opportunities (e.g., as romantic partners; lemay et al., ). from an evolutionary perspec- tive, physical attractiveness is highly valued because it serves as a cue to the health, level of genetic fitness, and fertility of potential partners (gangestad & simpson, ; kenrick & keefe, ; pflüger, oberzaucher, katina, holzleitner, & grammer, ; rhodes, ). when mating goals are active, people tend to categorize opposite-sex persons on their level of physical attractiveness (li & kenrick, ) and react favor- ably to good-looking persons of the other sex (maner & acker- man, ; maner et al., ). despite the generally positive effects of attractiveness, stud- ies with european caucasian samples also indicate negative effects of being attractive. people’s preference for attractive mates may lead them to perceive attractive same-sex persons as intrasexual rivals, and the perception of such rivals is linked with the activation of mate-guarding motives (maner & acker- man, ; maner, miller, moss, leo, & plant, ; maner, miller, rouby, & gailliot, ). this perception of attractive same-sex persons as potential rivals even occurs automatically and without awareness (buunk, massar, & dijkstra, ; mas- sar & buunk, ), thus pointing to an adaptive sensitivity to relevant social categories. because attractive same-sex persons elicit unfavorable upward social comparisons (jones & buck- ingham, ) and serve as intrasexual rivals over relationship opportunities (gutierres et al., ), people tend to perceive attractive same-sex individuals as threats to self-esteem (park & maner, ) and relationships (buss et al., ). consequently, as soon as people reach sexual maturity (agthe, spörrle, frey, walper, & maner, ), they tend to derogate (försterling, preikschas, & agthe, ; vaillancourt, ) and avoid (agthe, spörrle, & försterling, ; agthe et al., ) attractive same-sex persons. in addition, women display heightened vigi- lance to attractive intrasexual rivals during the fertile phase of their menstrual cycle, the time during which the women’s repro- ductive prospects are most salient (e.g., fisher, ). negative responses to attractive same-sex persons have been found not only in romantic contexts (maner, gailliot, rouby, miller, et al., ; maner et al., ) but also in organiza- tional decision-making (agthe, spörrle, & maner, ; luxen & van de vijver, ; ruffle & shtudiner, ). thus, for european caucasian samples confronted with same-ethnicity targets, the nature of attractiveness biases depends on whether one is evaluating a target of the same sex or the opposite sex. do attractiveness-based social evaluation biases generalize to other ethnic groups? the underlying adaptive social motives these attractiveness- based evaluation biases are designed to serve (cf. neuberg, kenrick, maner, & schaller, ; kenrick, delton, robertson, becker, & neuberg, ) are relatively universal across cul- tures and ethnicities (buss, ): despite cultural differences in the importance of attractiveness (anderson, adams, & plaut, ), persons from different cultures still regard attractiveness as a valuable criterion for mate choice (buss, ; chang, wang, shackelford, & buss, ; kamble, shackelford, pham, & buss, ), so that across cultures, attractive opposite-sex persons tend to receive favorable social evalua- tions (langlois et al., ). however, this preference for attractive persons seems to be limited to opposite-sex targets (li & zhou, ). in many cultures, attractive same-sex targets are regarded with jealousy (buss et al., ; dijkstra & buunk, ). hence, it is likely that also in non-european caucasian samples, people will per- ceive highly attractive members of their own sex and ethnicity as a threat and, consequently, will respond negatively toward them (e.g., derogate them). thus, we predicted that, across different ethnicities, participants would positively evaluate attractive opposite-sex targets, but negatively evaluate attrac- tive same-sex targets. we test this hypothesis in study . do attractiveness-based biases generalize to between-ethnicity evaluations? even though persons from different ethnicities and cultures tend to generally agree on whom they consider attractive (coet- zee, greeff, stephen, & perrett, ; cunningham, roberts, barbee, druen, & wu, ; rhodes, ; rhodes et al., ; zebrowitz, montepare, & lee, ), we predict that attractiveness-based biases will be reduced or even eliminated for between-ethnicity evaluations. that is, although an individ- ual may respond in a biased way to attractive members of their own ethnicity, such biases may not be as strong when members of a different ethnicity are evaluated. there are three (not mutually exclusive) reasons for this prediction: first, members of other ethnic groups may be rel- atively less likely than same-ethnicity targets to be seen as evolutionary psychology potential mates and romantic rivals (e.g., eastwick, richeson, son, & finkel, ; feliciano, robnett, & komaie, ; mcclintock, ). for instance, stephen et al. ( ) found that people’s ability to judge health cues (like natural skin color variation) for other-ethnicity targets is rather limited (com- pared with same-ethnicity targets). thus, people might be more sensitive to mating-related cues in targets who share their own ethnicity. this might partially result from socialization, such as the perception that family acceptance for a partner of another ethnicity would be rather low (mills, daly, longmore, & kil- bride, ; wang, kao, & joyner, ). yet, such intergroup biases (including preferences for same-ethnicity partners) may also be linked to adaptive motives such as greater caution and vigilance toward (particularly male) out-group members (maner & miller, ; olsson, ebert, banaji, & phelps, ). already young children show favorable reactions toward those who belong to their own social category (for reviews, see bigler & liben, ; hirschfeld, ; regarding ethnicity, see aboud, ; comer, ), and even though explicit ethnicity-related biases become more egalitarian across individual development, implicit attitudes favoring the in-group remain stable (baron & banaji, ; dunham, baron, & banaji, ). although it is unlikely that people have evolved to categorize others into racial or ethnic categories (see cosmides, tooby, & kurzban, ), race and ethnicity serve as important group markers in modern cultural contexts. accordingly, some studies find evidence for a potential (though not always strong and completely consistent) own-race preference in attractiveness judgments (burke, nolan, hayward, russell, & sulikowski, ; rhodes et al., , ). second, a key feature of whether a target person is perceived as a potential mating rival involves the perceived likelihood that a potential mate (whom oneself desires) would be inter- ested in the target person. given that people typically prefer to date and mate within ethnicity (e.g., hitsch, hortaçsu, & ariely, ; lin & lundquist, ; robnett & feliciano, ), one might perceive a relatively lower likelihood that a potential (or current) mate would view members of other eth- nicities as desirable partners. that is, one might be relatively less likely to see same-sex members of other ethnicities (versus the same ethnicity) as rivals because they are less likely to be viewed as desirable by one’s own romantic interests. third, other-ethnicity targets might be perceived as rela- tively less relevant for appearance-based social comparison because they appear to be less similar to the evaluator and are, thus, less likely to elicit self-other comparison (tesser, ; major, testa, & bylsma, ). that is, other-ethnicity targets are less likely to pose a threat to one’s self-esteem and to be perceived as a potential object of social comparison. accord- ingly, attractiveness-based biases are hypothesized to be stron- ger for targets of one’s own ethnicity than for targets of another ethnicity. we test this hypothesis in study . overview of the current research across cultures, adaptive mating-related motives may guide social perception (e.g., for caucasian samples, see maner, gailliot, rouby, miller, et al., , and for asian samples, see li et al., ). given that the social motives underlying attractiveness-based biases (e.g., mating, social comparison) are presumed to be relatively universal, we hypothesize that those biases will generalize to other-ethnicity samples evaluat- ing targets of their own ethnic background (study ). with regard to between-group effects, we hypothesize that european caucasians will display larger evaluative biases when judging members of their own ethnicity than members of other ethni- cities (study ). study study tests the hypothesis that, across samples from diverse non-caucasian ethnic backgrounds (i.e., asia [as], middle east [me], latin america [la]), people will evaluate attrac- tive same- and opposite-sex targets of their own ethnicity in biased ways (i.e., attractiveness will have a positive influence for opposite-sex constellations, and a negative influence for same-sex constellations). that is, paralleling the findings of caucasian samples these biases should generalize to the within-ethnicity evaluations of non-caucasian samples and be reflected in attributions as well as social interaction intentions. materials and method participants international students from la (n ¼ ), the me (n ¼ ), and as (n ¼ ) staying at german language schools and universities for language courses participated in our study. their mean age was . years (sd ¼ . ). all participants had advanced german-language skills. design and procedure for each ethnic group (i.e., la, me, as), study employed a (participant sex) � (target sex) � (target attractiveness; highly attractive versus less attractive) between-subjects design. similar to prior studies (agthe et al., ; försterling et al., ), participants received a scenario describing the occupa- tional history and success of a target person. it contained edu- cational (e.g., education in home country), occupational (e.g., employed as a doctor in germany), and social (e.g., family) background information about the target and highlighted the target’s early career success. this information was constant across all experimental conditions. in addition, the materials included a passport-sized black and white facial photograph of the target, which portrayed a male or female, highly attractive or less attractive person of each of the three different ethnic groups. photographs were prerated and selected for higher and lower attractiveness in an independent pretest: across ethnici- ties, attractive targets were between . and . and less attractive targets were between . and . on a -point rating scale. participants were randomly assigned to one of the agthe et al. four experimental conditions; all targets matched participants’ ethnic groups (i.e., each participant only saw a stimulus person of his or her own ethnicity). after reading the scenario, parti- cipants responded to measures of social evaluation and desire for social interaction as well as a manipulation check. the methods of both studies were evaluated and approved by a university research ethics committee. measures explicit measures of social evaluation can elicit social desir- ability effects and other response biases. thus, instead of ask- ing people to explicitly evaluate each target, we used a more implicit attributional measure used in previous research to tap underlying biases in social judgment (agthe et al., ; för- sterling et al., ). using items (from ¼ not important to ¼ very important), participants attributed the target’s early career success to ability as well as to luck. as in previous research, the difference score between these items served as dependent variable reflecting the extent to which partici- pants attributed the target’s successes to internal versus exter- nal causes. previous studies (agthe et al., ; försterling et al., ) have shown that positive social evaluations foster internal attributions of success (i.e., to ability), whereas nega- tive evaluations promote external attributions (i.e., to luck). subsequently, participants provided measures of their desire for social interaction with the target: participants reported the degree to which they would like to (a) work with the candidate and (b) become friends with the candidate ( ¼ not at all, ¼ very much). the two variables were highly correlated (. � r � . for the three samples) and were averaged to create a composite measure of desire for social interaction. as manip- ulation check, participants rated the target’s attractiveness from (unattractive) to (very attractive). results manipulation check in all three ethnic samples, the attractive targets (moverall ¼ . , sd ¼ . ) were perceived as better looking than the less attractive targets (moverall ¼ . , sd ¼ . ), ps < . , ds > . . evaluative attributions first, we examined the hypothesized participant sex � target sex � target attractiveness three-way interaction. as we detected no significant influence of ethnicity on this interaction (i.e., the four-way interaction was not significant, p > . ), aggregating across ethnicities in order to develop an overall impression of the data seems justified. a (participant sex) � (target sex) � (target attractive- ness) analysis of variance confirmed the hypothesized three- way interaction, f( , ) ¼ . , p < . , z ¼ . (no further main or interaction effects reached significance; for overall mean values, see bottom of table ). in order to eluci- date this three-way interaction, we decomposed it into two separate lower order two-way interactions for the two sexes of the respondents. these interactions were analyzed by means of simple main effects. we confirmed target sex � target attractiveness interactions for female participants, f( , ) ¼ . , p < . , and male participants, f( , ) ¼ . , p < . . women provided less positive attributions for attractive female targets compared with less attractive female targets, p < . , but provided more positive attributions for attractive male targets compared with less attractive male targets, p < . . male participants only tended to prefer less attractive males compared to attractive males, but this tendency did not reach table . means and standard deviations (in brackets) of evaluative attributions across ethnicities (study ). sex of target male female attractiveness of target attractiveness of target ethnicity and sex of participants low high low high latin american participants male participants . a ( . ) . b ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . a ( . ) . b ( . ) asian participants male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) middle east participants male participants . ( . ) . ( . ) . a ( . ) . b ( . ) female participants � . a ( . ) . b ( . ) . ( . ) . ( . ) all participants male participants . ( . ) . ( . ) . a ( . ) . b ( . ) female participants . a ( . ) . b ( . ) . a ( . ) . b ( . ) note. within each row and sex constellation of target and participant, means with different superscripts differ at p < . (based on independent t-tests). higher means indicate more positive attributions. evolutionary psychology significance, p ¼ . . however, they provided more positive attributions for attractive females than for less attractive females, p < . . these findings provide first evidence that the recently described three-way interaction between respondent sex, target sex, and target attractiveness found for european caucasian samples generalizes to non-caucasian samples. even though we detected no significant influence of ethni- city on the three-way interaction (see above), we conducted exploratory analyses for each ethnic group (i.e., la, as, and me) to confirm that the expected pattern was present in each of the three ethnicities (see table ). for all three ethnicities, we detected the hypothesized three-way interaction, fs > . , ps < . , which predominantly (i.e., in of [ethnicity] � [respondent sex-target sex constellation)] ¼ conditions) was in line with the hypothesized response pattern (i.e., more pos- itive evaluations for attractive targets in opposite-sex constel- lations and more negative evaluations for attractive targets in same-sex constellations, table ). the only exception was for males from the me who unexpectedly tended to show a (insig- nificant) preference for attractive male targets, p ¼ . . desire for social interaction as before, we examined the hypothesized participant sex � target sex � target attractiveness three-way interaction. because we again detected no significant influence of ethnicity on this interaction (i.e., the four-way interaction was not sig- nificant, p > . ), we aggregated data across ethnicities. a (participant sex) � (target sex) � (target attractive- ness) analysis of variance revealed significant main effects for participant sex, p < . , as well as target sex, p < . , indicating overall higher desire for social interaction intentions for female (compared to male) participants and concerning male (compared to female) targets. more importantly, these lower order effects were qualified by the hypothesized three-way interaction, f( , ) ¼ . , p < . , z ¼ . (for overall mean values, see bottom of table ). in order to elucidate this interaction, we followed the same analytical approach as before: lower order two-way interactions confirmed target sex � target attractive- ness interactions for female participants, f( , ) ¼ . , p < . , and male participants, f( , ) ¼ . , p < . . women expressed less desire to interact with attractive female targets compared to less attractive female targets, p < . , but greater desire to interact with attractive male targets compared to less attractive male targets, p < . . similarly, male participants were less inclined to interact with attractive male targets compared to less attractive male targets, p < . , whereas they expressed an increased desire to interact with attractive females compared to less attractive females, p < . . even though we did not detect a four-way interaction (i.e., no effect of the ethnicities on the three-way interaction), we analyzed the three non-caucasian samples separately. the hypothesized three-way interaction was (marginally) signifi- cant for each of the ethnic samples: la, f( , ) ¼ . , p < . ; as, f( , ) ¼ . , p ¼ . ; and me, f( , ) ¼ . , p < . . in each case, the pattern was completely in line with the hypothesized response pattern (i.e., more positive eva- luations for attractive targets in opposite-sex constellations and more negative evaluations for attractive targets in same-sex constellations, see table ). discussion findings from study provide some of the first empirical sup- port for the hypothesis that attractiveness-based biases in social evaluation (which operate in opposite directions depending on table . means and standard deviations (in brackets) of desire for social interaction across ethnicities (study ). sex of target male female attractiveness of target attractiveness of target ethnicity and sex of participants low high low high latin american participants male participants . a ( . ) . b ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . a ( . ) . b ( . ) asian participants male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) middle east participants male participants . ( . ) . ( . ) . a ( . ) . b ( . ) female participants . a ( . ) . b ( . ) . ( . ) . ( . ) all participants male participants . a ( . ) . b ( . ) . a ( . ) . b ( . ) female participants . a ( . ) . b ( . ) . a ( . ) . b ( . ) note. within each row and sex constellation of target and participant, means with different superscripts differ at p < . (based on independent t-tests). agthe et al. the sex constellation of respondent and target) generalize to non- western samples. in of the (¼ respondent sex-target sex combinations � ethnicities � depending variables) constel- lations, individuals positively evaluated attractive members of the opposite sex but negatively evaluated attractive (in compar- ison to less attractive) members of their own sex. these findings are in line with the notion that social comparison and adaptive mating-related motives (i.e., mate search and intrasexual com- petition)—which can be found cross-culturally—might contrib- ute to the bias. that is, positive responses might reflect approach motivation (toward attractive opposite-sex targets as social opportunities; lemay et al., ), whereas negative responses might reflect avoidance motivation (away from attractive same- sex targets as social threats; agthe et al., ). interestingly, the biased response pattern for participants’ desire for social interaction with same-ethnicity target per- sons was somewhat smaller in the as sample, which hints at potential cultural variations of the bias. for instance, this corresponds to findings indicating that reactions toward a partner’s imagined infidelity are somewhat less intense in as samples compared to western samples (geary, rumsey, bow-thomas, & hoard, ), which might point to lower underlying rivalry. yet, research with as participants accords with western findings that the preference for attrac- tive persons seems to be limited to opposite-sex targets (li & zhou, ). study to our knowledge, study is the first research that showed that attractiveness-based biases which depend on the sex constella- tion of respondent and target (i.e., consistent positive versus rather negative effects for opposite-sex versus same-sex target attractiveness) generalize to non-caucasian ethnicities’ within- group ratings. this has so far almost exclusively been docu- mented for european caucasian samples. study extends these findings by addressing corresponding between-ethnicity effects for the first time. based on considerations that self-other com- parison as well as mating-related motives tend to be less strong regarding other than one’s own ethnicity, study tests the specificity of attractiveness-based social evaluation biases. we hypothesize that these biases would be replicated for a caucasian sample evaluating caucasian targets (which would be in line with former findings) but would be reduced or elim- inated for caucasian participants evaluating non-caucasian (i.e., african, as, la, me) targets (which so far has not been empirically examined). materials and method participants a total of n ¼ , german participants of caucasian ethni- city were recruited at several universities across germany. their mean age was . years (sd ¼ . ). design and procedure study employed a (participant sex) � (target sex) � (target attractiveness; highly attractive vs. less attractive) � (target ethnicity) between-subjects design. the procedure was identical to that used in study . target ethnicities were: la (n ¼ ), me (n ¼ ), as (n ¼ ), african (n ¼ ), and caucasian (n ¼ ). however, unlike study , the caucasian-only sample of study provided eva- luations of targets from their own as well as from other ethni- cities. thus, only in the case of caucasian targets, participant and target were of the same ethnicity. in addition to the picture sets of study (i.e., pictures of la, me, and as stimulus persons), pretested picture sets of african and caucasian target persons (according to the same selection criteria as in study ) were used. measures we used the same measures as in study , that is, the difference scores of attributions to ability minus attributions to luck (con- cerning the target person’s occupational success), the -item measure (r ¼ . ) of desire for social interaction with the target person, and the manipulation check of target attractiveness. results manipulation check in all five target ethnicity samples, the attractive targets (moverall ¼ . , sd ¼ . ) were perceived as better looking than the less attractive targets (moverall ¼ . , sd ¼ . ), ps < . . same-ethnicity and other-ethnicity targets did not differ signif- icantly in the attractiveness ratings they received, p > . . thus, for all target ethnicities, the caucasian participants perceived attractive targets to be more attractive than less attractive targets. evaluative attributions we ran a (participant sex) � (target sex) � (target attrac- tiveness) � (ethnicity constellation: same [i.e., caucasian] versus different [i.e., all else]) analysis of variance. as hypothesized, we detected a significant four-way inter- action, f( , ) ¼ . , p < . , z ¼ . , confirming that the significant three-way interaction between respondent sex, target sex, and target attractiveness, f( , ) ¼ . , p < . , z ¼ . , varied as a function of whether respon- dents provided answers regarding their own or a different ethnicity. to further elucidate this complex finding of a four-way interaction, we ran separate analyses for respondents evaluating their own ethnicity versus another ethnicity: a (participant sex) � (target sex) � (target attractiveness) analysis of variance confirmed the hypothe- sized three-way interaction for european caucasian partici- pants evaluating caucasian targets (i.e., targets of their own ethnicity), f( , ) ¼ . , p < . , z ¼ . . in line with study and prior research, women provided less positive evolutionary psychology attributions for attractive female targets compared with less attractive female targets and tended to provide more positive attributions for attractive male targets compared to less attrac- tive ones. in contrast, male participants provided less positive attributions for attractive male targets than for less attractive male targets, whereas they tended to provide more positive evaluations for attractive compared to less attractive female targets (for mean values, see table bottom row). this three- way interaction did not reach significance when participants evaluated targets from other (i.e., non-caucasian) ethnicities, f( , ) ¼ . , p > . . when distinguishing between the different non-caucasian eth- nicities, no significant three-way interaction emerged for any of the non-caucasian target ethnicities either, fs < . , ps > . . there was neither a consistent pattern of attractive same-sex target derogation nor systematic evidence of glorification of attractive opposite-sex targets (for mean values, see table first four rows). desire for social interaction in line with the previous analysis, we ran a (participant sex) � (target sex) � (target attractiveness) � (ethnicity con- stellation) analysis of variance. as hypothesized, we detected a significant four-way inter- action, f( , ) ¼ . , p < . , z ¼ . , confirming that the three-way interaction between respondent sex, target sex, and target attractiveness, f( , ) ¼ . , p < . , z ¼ . , varied as a function of whether respondents provided answers regarding their own or a different ethnicity. we again ran separate analyses for respondents evaluating their own eth- nicity versus another ethnicity: when examining european caucasian participants evaluating only caucasian targets, a (participant sex) � (target sex) � (target attractiveness) analysis of variance confirmed the hypothesized three-way interaction, f( , ) ¼ . , p < . , z ¼ . . women expressed less desire to socially interact with highly attractive female targets compared to less attractive female targets, whereas they indicated increased intentions to interact with attractive male targets compared with less attractive male tar- gets. male participants provided less interaction intentions for attractive male targets than for less attractive male targets, whereas they tended to provide more desire for interaction for attractive compared to less attractive female targets (for mean values, see table bottom row). in line with our hypotheses and the already confirmed four-way interaction, this three-way interaction was not observed when respondents provided responses regarding targets from other ethnicities, f( , , ) ¼ . , p ¼ . (for mean values, see table first four rows). for explorative purposes, we ran separate analyses for the different ethnicities of the targets. we detected no three-way interaction for me, p > . ; as, p > . ; or african, p > . , ethnicities. however, we found a significant three-way inter- action with respect to la targets, f( , ) ¼ . , p < . , z ¼ . . for la targets, the caucasian female participants responded in line with how they responded to caucasian tar- gets; however, providing a less consistent picture, the cauca- sian male participants generally preferred attractive targets, although this preference was somewhat smaller when evaluat- ing male targets. this three-way interaction regarding la (i.e., other ethnicity) targets was significantly smaller than the pre- viously described interaction observed for caucasian (i.e., same-ethnicity) targets, f( , ) ¼ . , p < . . table . means and standard deviations (in brackets) of evaluative attributions across target ethnicities. sex of target male female attractiveness of target attractiveness of target ethnicity of targets and sex of participants low high low high latin american targets male participants . ( . ) . ( . ) . a ( . ) . b ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) asian targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) middle east targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) african targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) caucasian targets male participants . a ( . ) � . b ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . a ( . ) � . b ( . ) note. within each row and sex constellation of target and participant, means with different superscripts differ at p < . (based on independent t-tests). higher means indicate more positive attributions. agthe et al. discussion for european caucasian participants, we observed an interac- tion such that they responded in a relatively negative way to attractive (in comparison to less attractive) same-sex targets but in a more positive way to attractive (in comparison to less attractive) opposite-sex targets which was consistent with hypotheses. moreover, as hypothesized, this biased response pattern did not emerge for evaluations of other-ethnicity tar- gets. the attractiveness-sex constellation had no effect on the overall evaluations of other-ethnicity targets, thereby pointing to the possibility that the latter might be relatively less relevant for the respondents. this is consistent with preferences to date same-ethnicity partners (lin & lundquist, ; potârcă & mills, ) and findings of racial exclusion of other- ethnicity persons in mate search by different ethnic groups (e.g., as, caucasian, la), particularly regarding the mate pre- ferences of whites (herman & campbell, ; robnett & feliciano, ). moreover, persons from an ethnic group other than one’s own are more readily associated with the presence of threat (compared with persons of one’s own ethnicity; olsson et al., ). the only exception in the pattern found in this study per- tained to responses to la targets, such that desire for social interaction with la targets varied as a function of their attrac- tiveness. these results from the caucasian sample suggesting that positive responses to attractive opposite-sex persons as well as negative reactions toward attractive same-sex persons emerged more strongly for european caucasians and las than for targets from other ethnic backgrounds fit with findings indicating that caucasians seem to prefer whites and las as potential partners (feliciano et al., ), that mate poaching— which might enhance the sensitivity to rivalry—is more fre- quent in europe and la than in other (i.e., as or african) cultures (schmitt et al., ), and that la students are more likely than other ethnic groups to date interculturally (keels & harris, ). moreover, regarding partner preferences, the ‘‘latino-white boundary’’ seems to be less rigid than other ethnic barriers: latino americans tend to prefer other latinos or caucasians as mates (feliciano, lee, & robnett, ). this is in line with notions that mating rivalry is not completely limited to one’s in-group (klavina & buunk, ). however, the overall pattern for la targets was not the same as that for caucasian targets, and the pattern did not generalize to social evaluations. thus, on the whole, results suggest that attractiveness-based social evaluation biases did not generalize to between-ethnicity contexts. general discussion physical attractiveness exerts powerful biases on social percep- tion. recent research suggests that the well-documented posi- tive stereotypes about good-looking people reflect a desire for social interaction (lemay et al., ) because attractiveness often represents the presence of desirable social opportunities. conversely, negative social reactions may be directed toward attractive members of one’s own sex who are perceived as threatening in the context of social relationships (agthe et al., ). to date, this pattern has so far been documented almost exclusively in european caucasian samples. table . means and standard deviations (in brackets) of desire for social interaction across target ethnicities. sex of target male female attractiveness of target attractiveness of target ethnicity of targets and sex of participants low high low high latin american targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . a ( . ) . b ( . ) asian targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) middle east targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) african targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . ( . ) . ( . ) . ( . ) . ( . ) caucasian targets male participants . ( . ) . ( . ) . ( . ) . ( . ) female participants . a ( . ) . b ( . ) . a ( . ) . b ( . ) note. within each row and sex constellation of target and participant, means with different superscripts differ at p < . (based on independent t-tests). evolutionary psychology the current article contributes to the literature by demon- strating that (a) these biases generalize to samples from other ethnic backgrounds and (b) these biases do not apply when people are evaluating members of an ethnicity other than their own. the current findings thus provide new evidence for both the generalizability and the specificity of attractiveness-based biases in social perception. study extends prior research by showing that attractiveness-based social evaluation biases are not restricted to caucasian ethnicities from western cultures. when evaluat- ing members of their own ethnicity, as, me, and la partici- pants displayed positive biases toward attractive opposite-sex persons and negative biases toward attractive same-sex per- sons. the findings are consistent with evolutionarily inspired research (buss, ; buss et al., ), emphasizing the fact that, across many cultures, highly attractive individuals reflect both desirable mating opportunities (opposite-sex targets) as well as potential relationship threats (same-sex targets). our findings support the notion that attractiveness biases might be based, at least in part, on universal adaptive motives linked to mating and related social comparison processes. it is worth noting that explanations for attractiveness-based biases, which involve mate preferences and rivalry on the one hand, and social comparison as well as threats to one’s self- esteem on the other hand, are not mutually exclusive. because physical attractiveness represents a highly desirable criterion for mate choice across different cultures and ethnicities (buss, ), it is likely also to be relevant for social comparison and self-esteem cross-culturally. as prior research suggests (agthe et al., ; maner, gailliot, rouby, miller, et al., ), social judgment biases that emerge as a function of attractiveness are unlikely to be caused merely by concerns associated with self- esteem and social comparison. rather, these processes may in part reflect proximate manifestations of underlying adaptive mating-related motives. interestingly, the attractiveness-based biases were found both in women and men. although women generally compete more on the dimension of physical attractiveness than men do (dijkstra & buunk, ; townsend & levy, ), physical attractiveness is important for both sexes (e.g., asendorpf, penke, & back, ; luo & zhang, ), particularly in young adulthood. because women display a preference for good-looking men (e.g., niesta kayser, agthe, & maner, ), physical attractiveness also represents an important dimension of rivalry for men, although comparison dimensions such as status and dominance gain more and more importance for them with increasing age. study contributes to the literature by demonstrating that attractiveness biases are stronger when one is evaluating a mem- ber of one’s own ethnicity than when one is evaluating a member of a different ethnicity. european caucasian participants showed no significant attractiveness bias toward african, as, or me targets, despite recognizing other-ethnicity targets as highly attractive. the only exception to this pattern emerged for la targets: in line with the attractiveness stereotype, male and female participants wished to have contact with attractive opposite-sex persons. in addition, female participants preferred to avoid attractive same-sex targets. however, these attractiveness-based biases did not extend to social evaluations and were significantly smaller in size compared to the biased response pattern regarding same-ethnicity targets. attractiveness-based biases are presumed to be linked to mating-related motives and related social comparison processes (agthe et al., ; försterling et al., ; luxen & van de vijver, ). thus, although individuals certainly form and maintain romantic relationships with members of other ethnici- ties, the current findings are in line with evidence suggesting that mating-related social evaluation biases may be observed most strongly when individuals are exposed to members of their own ethnicity (eastwick et al., ; mcclintock, ; see also montoya, horton, & kirchner, ). particularly regarding the first stage of contact (i.e., when initiating romantic interest), the degree of self-segregation is comparably higher than when reci- procating romantic interest (lewis, ), so that a preference for persons of one’s own ethnicity may dominate mate-searching behavior for both men and women (lin & lundquist, ). given that prior research has often documented negative biases toward ethnic out-group members, it is interesting that, in the case of attractiveness-based biases within specific sex- constellations, being of a different ethnicity might sometimes be beneficial. there were actually less negative reactions toward attractive same-sex persons when the person being evaluated was of a different ethnicity, arguably because reduced similarity and comparability might have lessened the perceived threat to one’s relationships and self-esteem. the relatively smaller negative bias for out-group members can be contrasted with the numerous studies indicating strong neg- ative biases toward out-group members (plant, goplen, & kunstman, ; trawalter, todd, baird, & richeson, ; unkelbach, forgas, & denson, ). the differences in find- ings likely derive from the fact that the types of threat denoted by out-group members in previous studies (e.g., threat to phys- ical safety; maner et al., ) are categorically different than the type of threat typically posed by attractive individuals (e.g., threats to one’s romantic relationship). the emergence of different reactions to attractive opposite- sex and same-sex persons between and within ethnicities is consistent with the fundamental social motives framework (kenrick, neuberg, griskevicius, & schaller, ): due to their centrality over the course of human evolutionary history, motivational states associated with survival and reproductive success are able to direct processing of social information in order to manage the relevant benefits and costs of social life (kenrick, neuberg, griskevicius, becker, & schaller, ; neel, kenrick, white, & neuberg, ). mate search and intrasexual competition may functionally shape people’s reac- tions to attractive other sex versus same-sex persons when the targets appear relevant in the respective context, activating motives designed to avoid negative outcomes by potential riv- als and to gain access to potential mates. accordingly, our findings are in line with evolutionarily inspired empirical find- ings suggesting that adaptive motives such as mate seeking, agthe et al. mate retention, or self-protection can bias interpersonal percep- tion of, attention to, and cognitions about individuals who dif- fer in gender, physical attractiveness, and ethnicity (li et al., ; maner, gailliot, & dewall, ; maner et al., ; maner & miller, ; neuberg et al., ; schaller, park, & mueller, ). such effects often reflect adaptive biases meant to help individuals reap the benefits and avoid the costs associated with social living. one interesting question for future research pertains to whether or not the reduced attractiveness-based biases regard- ing out-group members might be specific for european cauca- sian respondents because individualistic (in comparison to collectivist) cultures generally show less inclination to devalue out-group members (triandis & gelfand, ). limitations and future directions limitations of the current research offer useful avenues for fur- ther investigation. one limitation is that study ’s non- caucasian participants were temporarily living in germany (for a language course or a semester as an exchange student). thus, the sample is relatively selective in that it only includes people who were able and willing to study abroad. moreover, some acculturation may have occurred because, by attending language education in germany, the other-ethnicity participants had already been heavily exposed to the influence of western media and culture. future research would benefit from examining dif- ferent ethnic groups in their own immediate cultural context. in study , the biases were less pronounced for the as sample compared to the la and the me sample, pointing to potential cultural differences in the strength of attractiveness- based biases. one factor to be examined in future studies regards the role attractiveness plays in mating choices within traditional societies; in traditional societies, mate choice is lim- ited by family expectations and kinship rules (yu & shepard, ), so the extent of individual choice that is allowed in personal relationships may affect attractiveness-based biases (adams, anderson, & adonu, ; anderson et al., ). therefore, differences could be expected between western cul- tures and more traditional cultures and societies. besides, social influence exerted by one’s environment and social net- work (e.g., one’s peer group) may affect perceptions of attrac- tiveness even in very different surroundings, economic states, and political climates (lehmiller, graziano, & vanderdrift, ; swami & tovée, ). in addition, in organizational contexts (which are often also influenced by culture), the anticipated level of competition or cooperation with a new colleague (i.e., the perceived instrumentality to oneself) may influence whether a person’s attractiveness and/or ethnicity (i.e., being of the same vs. another ethnic group) promotes negative versus positive reactions (lee, pitesa, pillutla, & thau, ; lee, pitesa, thau, & pillutla, ). moreover, other contextual factors like the target person’s status and achievements (agthe & spörrle, ), as well as individual differences like people’s social comparison orienta- tion (agthe, spörrle, frey, & maner, ), their own level of attractiveness (agthe et al., ), their sexual preference (för- sterling et al., ), sociosexual orientation (simpson & gangestad, ), or partnership status and commitment (lydon, fitzsimons, & naidoo, ) may influence whether positive or negative attractiveness-based biases are likely to emerge toward an other-sex versus same-sex target person. considering that our hypotheses referred to heterosexual parti- cipants, failing to measure sexual preference may have added noise to our current data, so it is important for future research to attend more carefully to people’s partner preference (i.e., whether they feel attracted to other-sex versus same-sex per- sons). it might also be helpful to use more precise ethnic cate- gories. for instance, people from as are likely to differentiate somewhat better than european caucasians whether a stimulus person from as is chinese, japanese, or from another asn country, and this may affect reactions to the target. besides, there might be substantial variability in reaction pattern across populations (heinrich, heine, & norenzayan, ). moreover, the tendency to stereotype on the basis of appear- ance when drawing characterological inferences may be weaker for people from collectivistic or interdependent cul- tures (e.g., east as) because individuals might rely more on group-level attributes when evaluating others (dion, pak, & dion, ; markus, mullally, & kitayama, ). such potential cultural influences on the nature of attractiveness- based biases could be profitably addressed in future research. although our results fall short of identifying the specific mechanisms underlying attractiveness biases within and between ethnicities, previous studies provide important clues. for instance, prior research has documented that the likelihood to have contact with the target person (luxen & van de vijver, ) and the desire to meet him or her (agthe et al., ; lemay et al., ) partly explain positive versus negative reactions toward attractive other-sex versus same-sex persons. future studies investigating the potential underlying processes for attractiveness-based biases within and between ethnicities would move us toward a better understanding of the observed patterns. for instance, investigations might test more directly whether particular target persons who vary in attractiveness elicit perceptions of threat associated with either romantic riv- alry or social comparison. testing potential mechanisms should also control for participants’ sexual preference, as the attention to the likely partner preferences might also explain why gay or lesbian participants might not show the same reac- tion patterns (försterling et al., ). conclusion the current studies are the first to show that positive (negative) biases toward attractive opposite-sex (same-sex) persons of the same ethnicity generalize across diverse ethnic backgrounds (within-group effects; study ) but emerge almost exclusively toward targets of the evaluator’s own ethnic background (between-group effects; study ). at a broader conceptual level, this research provides support for the notion that the motives underlying biases in social evaluation—including evolutionary psychology adaptive motives associated with mating and social compari- son—seem to be manifested in relatively universal ways across human cultures. at the same time, findings provide evidence for important boundary conditions in how—and toward whom—those motives are expressed. overall, our studies high- light the value of attending both to fundamental social motives shaped by natural selection as well as to possible cultural influ- ences when exploring biases in social perception. acknowledgments we thank our colleagues and our research assistants for their help with the data collection. in particular, we wish to thank rebecca dörfler, katrin zweier, eiko fried, sebastian wolf, erik danay, alexandra müller, christine obel, and martina servaty. as well, we wish to express our gratitude to our anonymous reviewers for their helpful comments on a former version of this article. declaration of conflicting interests the author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. funding the author(s) received no financial support for the research, author- ship, and/or publication of this article. references aboud, f. e. 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( ). they don’t all look alike: individual impressions of other racial groups. jour- nal of personality and social psychology, , – . evolutionary psychology << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /warning /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages false /createjdffile false /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /leavecolorunchanged /dothumbnails false /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize true /opm /parsedsccomments true 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/includelayers false /includeprofiles true /marksoffset /marksweight . /multimediahandling /useobjectsettings /namespace [ (adobe) (creativesuite) ( . ) ] /pdfxoutputintentprofileselector /documentcmyk /pagemarksfile /romandefault /preserveediting true /untaggedcmykhandling /usedocumentprofile /untaggedrgbhandling /usedocumentprofile /usedocumentbleed false >> ] /syntheticboldness . >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice searching for a job is a beauty contest munich personal repec archive searching for a job is a beauty contest busetta, giovanni and fiorillo, fabio and visalli, emanuela university of messina, university politecnica delle marche august online at https://mpra.ub.uni-muenchen.de/ / mpra paper no. , posted sep : utc searching for a job is a beauty contest giovanni busetta*, fabio fiorillo** and emanuela visalli abstract the paper deals with the impact of beauty on employability of people, stressing the first stage of the hiring process. in particular, we studied if there exists a preference for attractive candidates and if it does whether it depends on sex, physical features and racial characteristics. we monitored all relevant agencies offering jobs in italy from august to september sending cvs to advertised job openings. to do so, we construct fake cvs and we sent the same cv times, changing only name and surname, address, and the photo included. in particular, we sent cvs with photo of an attractive and unattractive man and women, and cvs without photo of an italian and a foreign men and women to each job opening. callbacks rates are statistically significant higher for attractive women and men than unattractive ones. racial discrimination appears to be statistically relevant, but less than discrimination based on the physical features, especially for women. keywords: beauty premium, racial discrimination, experimental economics. jel classification nos.: c , j , j . corresponding author: giovanni busetta gbusetta@unime.it . introduction aristotele said: “personal beauty is a greater recommendation than any letter of reference” after thousands of years this concept continues to hold. in nowadays’ society people are often discriminated for their physical attractiveness. discrimination based on the various components of physical appearance results in “premia” for those individuals characterized by certain attributes, and in penalties for persons failing to match the given standard. * *department of economics, buseiness, enviromental sciences and quantitative methods, università degli studi di messina, via t. cannizzaro , messina, italy ** **department of economics, università politecnica delle marche, piazzale martelli , ancona, italy  università degli studi di messina, italy. in france, the country of the enlightenment and human rights, people refer to the aesthetic discrimination in terms of “beautism”. this kind of discrimination is so widespread that several candidates to work positions use to include into their cvs, not only their skills and titles (such as education, languages spoken, experiences, etc), but also a “video resume” in which they present and enhances themselves. “pole d’eploi” is a french firm at which it is possible to attend a course called “action looking” to learn tricks and how to dress-up in order to encourage recruitment in job interviews. in this way, the selection of candidates for a job becomes similar to a casting. in italy this kind of discrimination appears to be particularly relevant. in “casting’s society”, an article published in on “la repubblica”, one of the main italian newspapers, anais ginori describes a survey published by sofres institute. the results of the survey show that clothing and manner of presentation improve the probability of being employed by % for candidates with same degree and experience. the economic crisis has made recruitment techniques even more ruthless. first impressions are crucial and, as the author wrote in the same article, this rule also applies to the work of back office. is such discrimination a novelty in italian labor market? actually, italy is a dualistic country. dualism is a common issue in italy and it is based on several explanations . it is the result of past determinants: sociological (differences in social capital, putnam ), economical (differences in workforce coming out from agriculture, bagnasco ) and institutional (formal norms vs informal rules, tabellini ). because of dualism, also the access to the job differs regarding regions: job opportunities, which reflect firms’ labor demand, were concentrated in the north and the center of the country and they are definitely much more for man than women (table ). table – italian employment and unemployment rate by macro areas and gender employment rate nor d cente r south italy male , % , % , % , % female , % , % , % , % total , % , % , % , % unemployment rate nor d cente r south italy male , % , % , % , % female , % , % , % , % total , % , % , % , % source: istat therefore, data reported in table depend on the number of firms and the industrial structure of the area which behaved differently in different regions. different firms behaviors not necessarily persist in the present as it was in the past. in particular, we wonder if, also in italy, the considerations underlined by the theory of beautism on the relevance of attractiveness premia in the hiring process could be more important than explanation based on dualism in influencing the probability of receiving a job offer. furthermore, italy is a growing immigration country. for this reason it is relevant to investigate whether italian labor market is affected by racial discrimination. as showed, among others, by a fratianni ( ). recent analysis performed by italy's national office against racial discrimination (unar), an institution which collaborate with united nations, discrimination based on race has increased by % between and . the main objective of this paper is to investigate whether the dualisms, traditionally characterizing italian labor market (e.g. discriminations based on region), are still the ones mainly influencing firms hiring decisions or whether, instead, there are new determinants to investigate on. if this is the case, what is, among education, nationality, job characteristics, gender and attractiveness, the most relevant variable affecting candidates’ probability to get a jog? since we want to analyse the influence of race and attractiveness in the hiring process, we have to face two problems common in literature. firstly, authors (biddle and hamermesh , mobius and rosenblat , parrett , eckel and ragan , etcoff, stock, haley, vickery and house ) commonly consider small samples of students answering hypothetical questions on hiring decisions, and, secondly, it is often impossible for researchers to control for employees' qualifications and abilities. on the contrary, in the analysis that we are going to present, we used an empirical strategy that, to our knowledge, has never been applied to italian labor market. this methodology consists in building up an ad hoc created database sending fake cvs to real job openings solving, in this way, both the two problems previously mentioned. indeed, we analyzed a huge sample based on cvs sent to real job offers posted by actual employers, obtaining callbacks (approximately % of the cvs sent). moreover, the design of our experiment (as already done for argentina by bóo, rossi, and urzua ) gives us the complete control and observability over candidates' backgrounds, solving in this way the second problem previously mentioned. in effect, our applicants are identical in every respect (including their education, work experience, language and computer skills) for each kind of job offer: name, nationality, sex, race and pictures (or lack thereof) are the only informations which change in between different cvs sent to the same job offer. moreover, the applications completely fulfill employer requirements regarding education, experience and so on. this methodology is similar to the one applied by ruffle and sthudiner ( ) to explore the effect of attractiveness (or lack thereof) on the likelihood of being invited for a job interview in israel. we added a racial component, as in bertrand and mullainathan ( ), to explore also the impact of racial discrimination. to control either for racial discrimination and for discrimination based on beauty, we sent identical resumes to firms, resumes with photo of attractive and unattractive men and women, and resumes without photo (two cvs for italian people, a woman and a man, and two for foreigners, a woman and a man). in this last case, african name and nationality are indicated in order to control for racial discrimination. our design strategy allows us to examine whether there exists a preference for attractive candidates, and whether this preference interacts with the applicant's sex and nationality. in our knowledge it is the first paper exploring simultaneously beauty, gender and racial discrimination in the hiring process in italy. main results obtained by this paper show that attractive women and men get much more callbacks ( % for attractive woman and % for attractive man) than unattractive ones, and that unattractive women get less callbacks than unattractive men ( % for woman and % for man). moreover, foreign women get less callbacks than the average callback rate, but much more than unattractive women ( % for foreign woman and % for foreign man). these results continue to hold even considering jobs not involving any face-to-face contact and/or highly qualified jobs. the rest of the paper is organized as follows. in section , we present the main literature on the topic. the experimental design is described in section . in section we present the main empirical results. section provides the conclusions to the paper. . related literature several jobs analyzed correlation between beauty and labor market, focalizing, in particular, on the relation between beauty and wages. feingold ( ) analyzes the association between physical beauty, personality features, health, cleverness and mental skills. in this respect. harper ( ) finds that the penalty for being unattractive is about % for men and % for women, because beauty is considered to be linked with social skills, health and intelligence. etcoff, haley, vickery and house ( ) included make-up as an additional element influencing common perception of individual’s features. in particular, they described the relationship between beauty, make-up and perceived reliability. a jury had to assign a score from to to the same face, before and after having changed make-up style from natural to professional, to glamorous. jury assigns a score for beauty, competence, pleasantness and reliability, assessing that make-up produces a significant effect in terms of the level of competence perceived. mobius and rosenblat ( ) provided evidence that the most beautiful workers are considered to be more confident, and their self-confidence determine a pay rise. biddle and hamermesh ( ) reached the similar conclusions studying data from the us and canada. their main findings were as follows: attractiveness plays an important role in deciding employees' earnings; the penalty for not being attractive is greater for women than men, and it is robust across occupations. in a different study on graduates from a prestigious law school (biddle and hamermesh, ), the same authors found that a weakly positive and insignificant relationship between attractiveness and earnings for lawyers becomes higher and significant as working years accrue. more recently boo et al. ( ) studied, the impact of beauty premium in the labor market sending resumes to real job openings in buenos aires. in particular, they sent resumes to each firm: resumes with photos of attractive men or women, with photos of unattractive men or women and resumes without photo. they manipulated electronically real photos and made them unattractive using photoshop. while resumes containing photos manipulated in order to appear as unattractive received % of callbacks, attractive photos received a callback rate of %. the two papers most similar to ours in methodology are ruffle and sthudiner ( ) and bertrand and mullainathan ( ). both the papers studied real job opening posted by actual employers in order to evaluate various kind of discriminations during the hiring process. while ruffle and sthudiner ( ) studied discrimination based on beauty, bertrand and mullainathan ( ) studied racial discrimination. ruffle and sthudiner sent resumes answering to job postings in israel. they sent to each offer different resumes, identical in every respect but the photo. they sent cvs including pictures of attractive men, women, unattractive men and women and with no photo included. they could study the photo effect because in israel is not that common to include photos into resumes. attractive men got relevant higher callback rates than men resumes with no photo and double than unattractive ones. on the contrary, for israelian women the two authors found relevant evidence of discrimination against attractiveness. thus, beautiful women including a photo on their resumes appear to be punished for their attractiveness and, consequently, to be more often discard by recruiters. bertrand and mullainathan ( ) sent fictitious resumes in the area of boston and chicago, considering all the job offers in the boston globe and chicago tribute sunday edition during the period between july and may in order to study the impact of racial discrimination. they sent low profile cvs with african american names and white names and high profile cvs with african american names and white names. using this method, the two authors found large racial differences in callback rates. applicants with white names needed to send about cvs to get one callback, whereas those with african american names had to send around resumes to get one callback. this percent gap in callback rates is statistically significant. based on their estimates, a white name yields as many more callbacks as an additional eight years of experience and, since applicants’ names are randomly assigned, this gap can only be attributed to name manipulation. as in the papers previously mentioned, our study is based on real job opening posted by actual employers. moreover, it includes both the aspects considered by ruffle and sthudiner ( ) and bertrand and mullainathan ( ), integrating the discrimination connected to attractiveness with the one connected to racial discrimination. in this respect, our research complements these studies. in effect, they found results on singular reasons underlying discrimination occurring at the earliest stages of the hiring process. on the contrary, we produced combined results in order to compare beauty, gender and nationality. . . experimental design and procedures our empirical experiment focuses on the impact of attractiveness in the hiring process. our study analyzed all job postings displayed in the period between august and september . in particular, we submitted resumes in response to employments ads published in the most important italian job search website, that does not require registration (e.g. lavoratorio.it, lavoro&stage, miojob, lavorare.net, page personnel, trovalavoro, kijiji, inique agenzia, archimede agenzia per il lavoro, manpower divisione horeca, combinazioni s.r.l, quanta agenzia per il lavoro, humangest, alma, orienta agenzia per il lavoro, varese centro per l’impiego, adecco, obiettivo lavoro, temporary agenzia per il lavoro, free work, maw, euro interim, mr comunication, open job). we produced resumes based on the european format and structure and we use fictitious names and addresses. to avoid matching problems, we modified them in order to fulfill the skills required by the firms offering jobs. we sent same resumes with same skills several times to all the companies, changing the photo attached or including no photo. for choosing the pictures to be included in the resumes, we selected photographs from internet and we modified them in order to make them unrecognizable. we then asked students at the university of messina to choose which of the people in the photos they considered to be attractive, and unattractive. as almost all of them ( %) agreed on the classification, we are confident that subjectivity can be excluded from the choice. we created a gmail account for each of the candidate categories, including this email address on the cv as contact information. the same resume has been sent to firms times: four resumes with different photos of applicants and without photos. in particular, a resume with photo have been sent including each time the photo of attractive and unattractive italian women, and attractive and unattractive italian man. a resume containing no photo of italian and of african (african origin can be inferred by name and nationality) person has been sent to each firm for both gender. in all, resumes for both male and female vacancies were sent to firms. applications from female (male) workers only were invited by ( ) firms, and ( ) resumes were sent to them, in this last case each firm received only four resumes per vacancy. actually, following the same procedure adopted by ruffle and shtudiner ( ), in order not to let employers realize that they were receiving identical resumes with different photos and names, we staggered over a few days the dispatch of the cvs to the same firms. for the same reason, we used different names and addresses. finally, all the residential addresses belong to the city of rome in order not to make the scrutinizers perceive differences in the candidates for residential reasons. in terms of distribution by genders, we sent more resumes of men (almost %) than women (almost %), because we got more job offers requesting exclusively men than exclusively women. moreover, we classified the cvs sent in terms of level of education required by the firm. according to it, our dataset is composed by % of jobs requiring university degree, % requiring high school diploma, and % of jobs not requiring any qualification. an other distinction in our dataset is between functions offered in job postings. in this respect, according to isco (international standard classification of occupation) definition, executive posts accounted for . % of job offers, specialized posts for . %, technical jobs . %, office jobs . %, commercial posts . %, artisans . %, drivers . % and unskilled work . %. dividing work categories into jobs involving and not involving face-to-face contact and implying and not implying physical strength we classified the cvs sent into front and back office, hard and soft work jobs. we defined front office and hard work either labors for which firms explicitly ask for, or the ones for which by no doubt it can be derived from isco classification. approximately % are back office and % are front-office jobs, % are hard work jobs and % are the ones which do not imply physical labor (soft work). table summarizes the characteristics of job openings in our dataset. we also considered regional distribution of job offers (see table ). as it might be reasonably expected lombardy ( . %), veneto ( . %), tuscany ( . %) and lazio ( . %) are the regions with most of the job offers, while the other regions are characterized by far fewer vacancies. . results table and , already mentioned in section , present also the results of the call back rates classified according to our database. analyzing callback rates in respect to attractiveness, we can show that attractive italian people have much higher call back rates ( %) than unattractive ones ( %) and than italians with no photo ( %). also racial discrimination appears to be relevant. table shows widely lower callback rates for foreigners candidates ( %). according to gender classification, men get % of callbacks, while women get %. considering together beauty, nationality and gender, we obtained an interesting result in terms of differences in callback rates. graf. – distribution of callback rates by attractiveness and gender iaw= italian attractive woman, npiw= italian woman (no photo), iuw= italian unattractive woman, npfw= foreign woman (no photo), iam= italian attractive man, npim= italian man (no photo), ium= italian unattractive man, npfm= foreign man (no photo) italian attractive women (from now on iaw) and italian attractive man (from now on iam) are called back on average respectively % and % of the times. gender is quite relevant for unattractive candidates, indeed italian unattractive men (from now on ium) obtain % of callbacks, while italian unattractive women (iuw) obtain a widely lower callback rate ( %). attractiveness appears to be then widely relevant in the hiring process especially for women and, in particular, for unattractive ones (graf. ). in respect to racial discrimination, foreign people are relevantly lower called back than italian candidates, without relevant discrimination based on gender. foreign women and men (from now on npfw and npfm) are actually called back with almost the same percentage. ( % for npfw, and % for npfm), but widely lower than the callback rate obtained by the correspondent italians resumes with no photo ( % for women and % for men). according to the qualification required, we obtained the highest callback rates for jobs which do not require any qualification ( %), while jobs for graduate candidates obtain % and jobs for which it is required high school diplomas obtain % (table ). in terms of isco classification of jobs, we have % for unskilled occupations, % for service workers, % for workmen artisan and drivers, and % for executives and for clerical jobs. definitely lower callback rates characterize technical ( %) and specialized job ( %), and sales workers ( %). regarding the categories hard and “soft” works and front and back office, we obtained % of callback rates for jobs implying hard work, % for the ones not implying hard works, % for the ones implying back office work and % for the ones implying front office works. table – summary statistics cvs sent call back rate candidate characteristics picture attractive italian % % italian with no photo % % unattractive italian % % foreigner with no photo % % gender men % % women % % job characteristics public / office front office % % back office % % strength hard work % % soft work % % qualification required no qualification % % high school % % graduated % % function offered executives % % specialized labor % % technical jobs % % clerical jobs % % sales workers % % service workers % % workmen, artisans and drivers % % unskilled workers % % as displayed in table , the jobs offered (i.e. the number of cvs sent to each region) differ among regions according to the performance of the labor market in the area (as showed in table ). we also expect some differences in call back rate, since in the south vacancies are fewer than in the center and in the north. for this reason, competition among applicants should be higher and thus we may expect lower callback rate. on the contrary, differences in call back rates exist, but companies placed in umbria, abruzzo, trentino alto adige, sicily, campania and calabria are characterized by higher callback rates (respectively %, %, %, %, and %). definitely lower call back rates characterize, instead, regions like molise, valle d’aosta, lombardy, marche, piedmont, and tuscany (respectively % the first one, % the second and the third, % the forth, the sixth and the seventh). table – distribution of cvs sent and callback rates by regions of the offering firm regions cvs sent call back rate piedmont % % valle d'aosta % % lombardy % % trentino alto adige % % veneto % % friuli venezia giulia % % liguria % % emilia romagna % % tuscany % % umbria % % marche % % lazio % % abruzzo % % molise % % campania % % puglia % % basilicata % % calabria % % sicily % % sardinia % % total % % our objective is to investigate whether regional differences, traditionally characterizing italian labor market are still the ones mainly influencing hiring decisions, or whether, instead, there are new determinants to investigate and, if this is the case, which are the most relevant. in order to investigate this issue, we performed an analysis of the variance classifying possible reasons of discriminations into the ones associated to gender, nationality, attractiveness, jobs classification and/or characteristics, regions. these variables, from table and , seems to determine differences in terms of job offers rates and of call back rates. secondly, we test some classification created by the “interaction” among these single variables. the intuition is that the best classification to be chosen is the one which display the highest variance between groups and the lowest within them. table shows the results of the total variance analysis referred to the cvs sent and its decomposition into particular subsamples. analyzing all the single categories results on variance decomposition, we note that the variance between groups is very low for regional ( % of total variability) and isco job classification ( %). also education (variance between amount to %) and isco classification of jobs does not appear to be a good classifier. good classifications can be obtained only if we consider attractiveness and its interactions with gender and nationality. table - variance analysis categories between total percentage f significance attractiveness only for italian , , % , attractiv. only for ital. men , , % , attractiv. only for ital. women , , % , attractiveness and nationality , , % , gender , , % , gender only for italian , , % , gender only for foreigner , , % , , gender only for attractive italian , , % , gender only for unattractive italian , , % , nationality , , % , attractiveness, gender and nationality , , % , attractiveness and gender only for italians , , % , isco classification of jobs , , % , education , , % , region of the firm , , % , jobs implying face to face contact , , % , hard work jobs , , % , gender seems to be a bad classificatory variable (between variance amount to %). only for unattractive people this classification seem to work (between variance %). attractiveness appears to be relevant by itself (between %), even if it does not increase its relevance when considering its interaction with gender. even nationality appears to be relevant considered by itself (between variance %), while its interaction with gender doesn’t seem to have any effect. we obtain the best classification when we interact gender, nationality and attractiveness (variance between %). interaction with gender, attractiveness and nationality with other variables do not have significant results. furthermore, other interesting results come out when we apply anova on subsamples. in particular, the impact of attractiveness seems to be gender bias, while no gender bias emerges for foreign people. in any case, the results coming out from the analysis show new tendencies in hiring process discrimination, which take into account determinants connected more to attractiveness than any other kind of difference between candidates. more information can be extracted if we apply the most relevant classification defined by anova on the distribution of the cvs receiving respectively positive and no answers. when we compare the conditioned distributions with the theoretical one coming out from our experimental design, we immediately see that this distribution is not independent from call back rates distribution. we test null hypothesis of independence between classification and call backs in table and, rejecting the null, we have an additional check to confirm the result of anova. table – test of independence h = independence (marginal means = conditioned mean) h = dependence (marginal mean ≠ conditioned mean) x di pearson = , ; df = ; p-value = the discrepancies are significant; h = refuses as shown in table conditioned distributions are different from marginal one, except for unattractive men. moreover, it is interesting to note that attractiveness appears to be much more polarized for women than for men and that, in particular, the beauty penalization for unattractive women is higher than the beauty premium for attractive ones. table - discrimination tests frequencie s for positive answers (n= ) frequencies for no answers (n= ) categories marginal distrib. freq. stand. dev. z values for pos. answers freq. stand. dev. z values for no answers italian attractive women , , , , , , - , italian women (no photo) , , , , , , - , italian unattractive women , , , - , , , , foreign women (no photo) , , , - , , , , italian attractive , , , , , , - , men italian men (no photo) , , , , , , - , italian unattractive men , , , - , , , , foreign men (no photo) , , , - , , , , . conclusion from the performed analysis we observed the existence of a significant social problem of discrimination in hiring process in italy. unlike what one could expect, discrimination in callback rates is neither based on regional differences, nor on lower employability of women, but on other aspects. in other word, the dualism in the labor market seems not to affect an applicant’s probability to receive a positive callback from a firm . the new tendencies of employability are based on attractiveness much more than traditional regional differences, or the ones based on education and job characteristics. moreover, in italy we measured a relevant discrimination based on nationality. gender’s impact on discrimination become trickier than the one which traditionally concerned italian labor market. in effect, gender seems to have little discriminatory effect considered by itself, but it takes relevance when it is interacted with attractiveness, especially for women. to summarize our main results, we could say that if you want a job in italy and you are not italian, it will be difficult to find it, but it is always better to be foreigner than to be an unattractive italian woman. thus, searching for a job seems to be just like a beauty contest: it is better for unattractive women to invest on aesthetic surgery than in education. references bagnasco a. 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( ), “the scope of cooperation: values and incentives”, quarterly journal of economics, : – . brief report is better beautiful or is beautiful better? exploring the relationship between beauty and category structure megan sanders & tyler davis & bradley c. love published online: december # psychonomic society, inc. abstract we evaluate two competing accounts of the rela- tionship between beauty and category structure. according to the similarity-based view, beauty arises from category structure such that central items are favored due to their increased fluency. in contrast, the theory-based view holds that people’s theories of beauty shape their perceptions of categories. in the present study, subjects learned to catego- rize abstract paintings into meaningfully labeled categories and rated the paintings’ beauty, value, and typicality. inconsistent with the similarity-based view, beauty ratings were highly correlated across conditions despite differences in fluency and assigned category structure. consistent with the theory-based view, beautiful paintings were treated as central members for categories expected to contain beautiful paintings (e.g., art museum pieces), but not in others (e.g., student show pieces). these results suggest that the beauty of complex, real-world stimuli is not determined by fluency within category structure but, instead, interacts with people’s prior knowledge to structure categories. keywords aesthetic preferences . categorization . halo effect . fluency beauty is mysterious. we know it when we see it, but it eludes explanation. one facet of beauty that has been explored is its relationship to category structure, and in psychology, two possible relationships have been sug- gested. the first line of research explores how beauty arises from the feature structure of categories. for ex- ample, golden retrievers may be considered beautiful dogs because they are typical of the category dogs, sharing many features with other dogs. a second line of research instead explores how beauty contributes to the structure of categories, as when beautiful individuals are perceived to be better leaders and more electable (berggren, henrik, & poutvaara, ). together, these two views present a conundrum: beauty is viewed as both arising from and contributing to the structure of categories. the present study disentangles these two accounts. the first line of research, which we will refer to as the similarity-based view, holds that similarity relationships among category members play an important role in determin- ing beauty. according to this view, items that are central by virtue of sharing features with other category members tend to be judged typical of their category and are processed more fluently (nosofsky, ; rosch, ; storms, de boeck, & ruts, ). fluency and familiarity are theorized to increase positive affect (zajonc, ), which, in turn, is thought to increase perceptions of beauty (reber, schwarz, & winkielman, ). for example, among a golden retriever, a daschund, and a great dane, the golden retriever is the most similar to other dogs in its size, proportions, and other char- acteristics and should be judged the most typical and the most beautiful of the three, according to the similarity-based view. analogously, face morphs (langlois et al., ), line draw- ings of animals (halberstadt & rhodes, ), and a variety of other real-world (halberstadt, ) and artificial (winkielman, halberstadt, fazendeiro, & catty, ) stimuli electronic supplementary material the online version of this article (doi: . /s - - - ) contains supplementary material, which is available to authorized users. m. sanders (*) the ohio state university, w woodruff ave, ramseyer hall , columbus, oh , usa e-mail: sanders. @osu.edu t. davis the university of texas at austin, austin, tx, usa b. c. love university college london, london, uk psychon bull rev ( ) : – doi . /s - - - http://dx.doi.org/ . /s - - - with features that are central for their category are judged to be more beautiful than atypical category members. importantly, the similarity-based view predicts that, by virtue of being fluently processed, highly typical objects should be viewed as the most beautiful. according to a second line of research, referred to as the theory-based view, people’s perceptions of an item’s beauty combine with prior beliefs about the category to shape the structure of the category. rather than arising from category structure, beauty can be a determinant of category structure. this view follows from theories of categorization suggest- ing that people’s prior beliefs, expectations, and intuitive theories of the category, rather than featural-similarity rela- tionships among category members, determine typicality structure (heit, ; murphy & medin, ; wisniewski & medin, ). on this view, yao ming is a good example of a professional basketball player because he satisfies cer- tain expectations about the category (e.g., high scoring percentage, good rebounder, etc.), not because he shares many features with other category members. in the case of basketball players, beautiful players are not necessarily viewed as central or typical category members, because beauty does not play a central role in people’s intuitive theories concerning basketball. however, in other domains, such as art, beauty does play a prominent role in people’s intuitive theories and, therefore, should influence category structure. thus, depending on the role beauty plays in people’s prior beliefs and expectations about a category, the theory-based view suggests that being beautiful (or not) can make an object either more or less typical of that category. one example of a theory-based attribution is the halo effect (asch, ; thorndike, ), whereby attractive individuals are perceived as more socially competent (eagly, ashmore, makhijani, & longo, ; feingold, ), happier (dion, berscheid, & walster, ), more trustworthy (wilson & eckel, ), and more competent in their occupations than others (langlois et al., ). from a theory-based view, beautiful objects are not beautiful be- cause they are typical or share more features with other category members. rather, beauty can make an object seem more typical of its category when the category is associated with other positive characteristics (e.g., intelligence) or peo- ple have a prior expectation about how beauty relates to the category. thus, we broadly define similarity-based views as bottom-up processing of category members’ features and theory-based views as top-down reasoning based on catego- ry labels. these two views, although divergent, are not necessarily mutually exclusive: there are multiple determi- nants of category typicality (e.g., barsalou, ; lynch, coley, & medin, ), and bottom-up and top-down pro- cesses could be active simultaneously. however, we clearly define the views such that they make different, testable predictions. we evaluated the two views using a task in which sub- jects learned to categorize works of abstract modern art as pieces from a college seniors’ art show or an art museum. the paintings used in our task were composed by profes- sional artists (table ), were largely unfamiliar to the subject pool, and were found in a previous multidimensional scaling (mds) study to vary on two psychological dimensions: geometry, or how curvilinear versus angular a painting was, and complexity, or how “busy” the painting appeared (fig. ). the paintings were grouped, between subjects, into two categories on the basis of their similarity along one of the dimensions. some subjects learned a category structure in which the paintings were grouped on the basis of differ- ences in geometry, whereas other subjects learned a struc- ture in which paintings were grouped on the basis of differences in complexity (fig. ). we followed others (palmeri & blalock, ; wisniewski & medin, ) in using meaningful category labels for these groupings to test the effects of theories; both the art museum and the student art show were perceived as equally likely sources of the paintings (see the supplementary material). by systematically manipulating the grouping of paintings and the category labels associated with them, it is possible to test key predictions from both the similarity- and theory- based views of beauty. both views predict that typicality and beauty will be correlated but differ in terms of the direction of the correlation and how the relationship between beauty and typicality will differ between the art museum and stu- dent art show category labels. the similarity-based view predicts that featural similarity drives typicality and processing fluency, thereby affecting perceptions of beauty. according to this view, perceived typicality should differ depending on how the paintings are grouped. because the present study uses two strongly con- trasting categories, items that are furthest from members of the opposing category in the mds space (i.e., share the least number of features with opposing category members) are processed most fluently and are perceived as more typical (davis & love, ). thus, the paintings at the extremes of the dimension used for grouping (e.g., highly complex paintings or very simple paintings, when the grouping di- mension is complexity) should be rated the most typical of their categories, the most fluently processed, and hence, from a similarity-based view, the most beautiful. in contrast, the theory-based view does not predict that changes in typicality and fluency caused by differences in grouping will affect perceptions of beauty. rather, this view suggests that perceived beauty should impact typicality structure, as per the halo effect. more important, it also predicts a difference in this effect depending on category label, because subjects may have different prior expectations psychon bull rev ( ) : – table paintings used in both the multidimensional scaling (mds) study and the rating study title artist year mds coordinate: geometry mds coordinate: complexity mean beauty rating sd cadmium red over black adolph gottlieb − . − . . . octavio paz suite–nocturne vi robert motherwell − . − . . . beside the sea # robert motherwell − . − . . . ochre and black adolph gottlieb − . − . . . rite of passage iii robert motherwell − . − . . . trees in blossom piet mondrian − . . . . unknown andre masson s − . . . . mallarme's swan robert motherwell − . . . . composition vii wassily kandinsky − . . . . pictograph–tablet form adolph gottlieb − . . . . red square: painterly realism of a peasant woman in two dimensions kasimir malevich . − . . . composition with red, blue and yellow piet mondrian . − . . . red, orange, tan and purple mark rothko . − . . . collage with squares arranged according to the laws of chance hans arp . − . . . composition no. piet mondrian . − . . . composition piet mondrian . . . . composition viii wassily kandinsky . . . . suprematist painting kasimir malevich . . . . victory boogie-woogie piet mondrian – . . . . proun e el lissitzky . . . . fig. the stimuli organized into four quadrants defined by two dimensions, geometry and complexity. geometry describes the angularity of the lines and shapes in a painting, whereas complexity arises from the number of shapes and degree of overlap in a painting psychon bull rev ( ) : – about how beauty relates to art museums and student art shows. appearing in an art museum indicates that a piece is considered by experts to be beautiful or valuable (danto, ). artworks are also expected to be beautiful when created by famous artists (isham, ekstrom, & banks, ), and the same pieces are perceived as more beautiful when created by a professional rather than by an amateur (duerksen, ) or by a computer (kirk, skov, hulme, christensen, & zeki, ). we confirmed that these find- ings extend to the paintings in our stimulus set (see the supplementary material). thus, subjects likely expect that paintings appearing in an art museum, a place populated with the work of famous, professional artists, will be beau- tiful. in contrast, appearing in a student art show does not carry this strong positive connotation. specifically, the theory-based view predicts that beauty will be insensitive to the groupings of paintings along the two dimensions (geometry and complexity) and the associated changes in typicality and fluency. instead, beauty will lead to increases in typicality, but only when the paintings are labeled as art museum pieces. method subjects ninety-three undergraduates from the university of texas participated for class credit. five were excluded for failing to exceed chance in the learning phase; mean categorization accuracy for all others was . % (sd . ). materials stimuli consisted of abstract paintings (see fig. ) with- out a recognizable topic to ensure that subjects focused on paintings’ perceptual characteristics instead of their subject matter. these paintings were determined to vary continu- ously along two perceptual dimensions, geometry and complexity. design and procedure categorization task paintings were grouped into four quadrants depending on their values along the geometry and complexity dimensions (see fig. ). counterbalanced across subjects, two adjacent quadrants (roughly matching on geometry or complexity) were assigned a category label (“student art show” or “art museum”), with the remaining stimuli assigned the other label (see fig. ). during learning, each subject completed three trial blocks, which consisted of the individual presentation of the stimuli in a random order, for a total of learning trials. on each trial, subjects were presented with a painting and were instructed to categorize it, on the basis of its visual forms, as a piece from an art museum or a student art show. fig. the four possible combinations of category structure and labeling. in the categorization task, subjects were trained to categorize paintings as either student art show or art museum pieces. paintings with roughly the same level of either geometry or complexity (see fig. ) were grouped together to form a category psychon bull rev ( ) : – after they responded, the screen cleared, and feedback was presented for , ms, indicating the correct category assignment. following feedback, a white screen was pre- sented for , ms. rating tasks after the category-learning task, subjects were instructed to rate each painting’s typicality (how well the painting repre- sented its category), beauty (how appealing its visual forms were), and value (how valuable it was). the typicality, beauty, and value rating tasks followed this instruction in that order. within each task, each painting was presented once in a random order. on each trial, subjects were pre- sented with a painting and, , ms later, a -point scale with low-, center- and high-points labeled not at all, some- what, and extremely in terms of the characteristic to be rated in that task. after subjects keyed their rating, a white screen was presented for , ms. results relationships among the basic variables ratings of typicality, beauty, and value had high interrater reliability, as measured by cronbach’s coefficient alpha (. , . , and . , respectively). for descriptive purposes, we aver- aged over subjects to obtain mean ratings for beauty, value, and typicality for each painting. beauty and value ratings were highly correlated in both categories [art museum, r . , t ( ) . , p < . ; student art show, r . , t( ) . , p < . ], suggesting that subjects considered the same quality of the paintings when rating both of these characteristics. overall, neither beauty nor value was significantly correlated with typicality [beauty, r . , t( ) . , n.s.; value, r . t( ) . , n.s.]; we explore the impact of category labels on this relationship in our hypothesis tests below. however, given the strong correlation between beauty and value, subsequent analyses focused on beauty, the main variable of interest. many of the measures of processing fluency were also correlated: typicality and categorization reaction time were significantly negatively correlated, r −. , t( ) − . , p < . ; typicality and categorization accuracy were significantly positively correlated, r . , t( ) . , p . ; and reaction time and categorization accuracy were negatively correlated, but not significantly, r −. , t( ) − . , n.s. similarity-based versus theory-based views of beauty similarity- and theory-based views predict different patterns of results in terms of how the category structure (grouping of stimuli with respect to geometry or complexity dimen- sions) and category label (art museum or student art show) factors will relate to our measures of fluency and subjects’ perceptions of beauty. the similarity-based view predicts that stimulus grouping should affect perceptions of typical- ity, processing fluency, and subjects’ perceptions of beauty. the theory-based view suggests that beauty will not be affected by changes in category structure or processing fluency but, rather, will lead beautiful items to be perceived as more typical and processed more fluently when they are labeled with the art museum label. we address each of these questions in a series of cross-classified random effects mod- els that test the relationships between category structure, beauty, and measures of typicality and fluency while con- trolling for subject- and painting-level variability (bayeen, davidson, & bates, ). conceptually, these random ef- fect models are akin to running a separate regression for each subject and testing whether the mean slopes (bs below) relating our variables (e.g., typicality and beauty) are signif- icantly different from zero across subjects. however, by estimating each subject’s slope simultaneously, we are able to pool information from the group-level data to better estimate individual subject slopes and simultaneously ac- count for mean differences in our measures (e.g., beauty) between paintings. category structure affects processing fluency and perceptions of typicality, but not beauty because the similarity-based view does not predict differ- ences based on label, ratings were collapsed across the two label conditions. following previous research using strongly contrasting category pairs (davis & love, ), typicality and measures of processing fluency increased as a painting became more distant from the boundary separating catego- ries along a grouping dimension (e.g., more angular in the high geometry category or more curvilinear in the low when these ratings were examined in light of the mds results, more geometric paintings were rated more typical, r . , t( ) . , p . , and more complex paintings rated were rated more beautiful, r . , t( ) . , p < . ; these relationships did not vary as a function of category label. complexity was included as a factor in all models that included beauty to control for the correlation between the two, and doing so did not change the nature of the results. additionally, beauty was centered according to each subject’s mean in all models to reduce colinearity in the random effects. the relationships between distance-to-the-bound and fluency, distance-to-the-bound and beauty, and beauty and fluency are tested in groupings made according to theory (collapsed across category labels when testing the similarity-based view and collapsed across grouping conditions when testing the theory-based view). however, these relationships are consistent across all possible groupings and across experimental condition, which was counterbalanced between subjects. psychon bull rev ( ) : – geometry category, when paintings were grouped with re- spect to geometry). distance-from-the-bound significantly predicted typicality, b . , t( ) . , p . , reaction time, b −. , t( ) − . , p < . , and probability correct, b . , z . , p < . , such that as paintings became more extreme in relation to the grouping dimension, they were perceived as more typical and were categorized more quickly and more accurately. however, distance-from- the-bound did not affect ratings of beauty, b −. , t( ) − . , n.s. instead, across subjects, paintings’ beauty ratings when categories were grouped with respect to geometry were very similar to and highly correlated with their beauty ratings when categories were grouped with respect to com- plexity, r . , t( ) . , p < . (see fig. ). these results are inconsistent with the similarity-based view. the paintings that were processed fluently and perceived as typical changed when the grouping dimension changed, but the paintings that were rated as beautiful did not. beauty contributes to typicality in the art museum condition the theory-based view predicts that beauty should increase typicality and, by extension, processing fluency for paint- ings assigned the art museum category label—a label asso- ciated with prior expectations of beauty. thus, because category structure is not predicted to impact typicality and fluency, ratings were collapsed across grouping conditions. as was predicted, for typicality and processing fluency measures, beauty and category label significantly interacted such that the relationship between beauty and fluency was significantly greater for paintings labeled as museum pieces than it was for paintings labeled as student show paintings [typicality, bam . vs. bss −. , t( ) . , p . ; reaction time, bam −. vs. bss . , t( ) − . , p . ; probability correct, bam . vs. bss −. , z . , p < . ] (see table and fig. ). for art museum pieces, these relationships were significantly different from zero [typicality, t( ) . , p < . ; reaction time, t( ) . , p . ; probability correct, z . , p < . ]. however, for student show paintings, the effect of beauty was not significant [typicality, t( ) − . , n.s.; reaction time, t( ) . , n.s.; probability correct, z − . , n.s.]. these results are consistent with a theory-based view: beauty impacted category structure by contributing to how typical paintings were perceived to be and how fluently they were processed, but this increase was significant only for the art museum category, which has a strong prior relationship to the concept of beauty. notably, when considered simultaneously, both beauty and distance-from-the-bound contributed significantly to fluency and typicality (see table ), suggesting that beauty and grouping contribute independently to the art museum category’s typicality structure. thus, even though groupings did not impact painting beauty, both similarity- and theory- based factors may influence category typicality structure. discussion together, the results are inconsistent with the predictions of the similarity-based view and in accord with the theory- based view. beauty does not arise from increases in typical- ity or fluency caused by category contrast. instead, beauty contributes to the structure of categories for which subjects have strong prior expectations about beauty: category mem- bers that are perceived as beautiful are viewed as more typical and are more fluently processed. indeed, the fluency with which paintings were processed varied across different r = . t( ) = . , p < . : low geometry/low complexity : low geometry/high complexity : high geometry/low complexity : high geometry/high complexity fig. relationship between mean beauty ratings when category structure is determined by grouping paintings by shared geometry versus complexity. inconsistent with the similarity- based view, judgments of beau- ty are unaffected by category structure psychon bull rev ( ) : – groupings in our experiment, but beauty did not. instead, we observed a halo effect whereby art museum paintings that were considered beautiful were rated more typical and pro- cessed more fluently. the theory-based view suggests that the different impact of beauty on typicality between the two category labels reflects differences in subjects’ expectations. art museums are expected to contain beautiful and valuable artworks, which causes beautiful paintings to be considered better, more typical examples of art museum pieces. because student art shows are not as strongly associated with beautiful art, beauty did not contribute to this cate- gory’s typicality structure. one potential criticism of the present study is that we have left beauty itself unexplained, a je ne sais quoi that paintings either have or do not have. because we do not offer an account of beauty’s origins, a similarity-minded researcher may sug- gest that perhaps beauty is determined by similarity to an abstract art concept collated over an individual’s lifespan, not the art museum and student art show categories that subjects learned here. although we do not discount the role that previous experience may play in shaping perceptions of beauty, the mechanisms by which similarity to a long-term average would affect perceptions of beauty is not clear. from a similarity-based view, averages are thought to impact percep- tions of beauty via processing fluency. our results demon- strate that fluency, in and of itself, is not what gave rise to perceptions of beauty in the present experiment, and so a similarity-based view that depended on similarity to a long- term average would need to offer a different mechanism. indeed, an approach that relied on processing fluency as a cause of beauty would have a difficult time explaining why student art show paintings that were processed more fluently were not rated as more beautiful. to this end, our experiment may explain some additional observations in the beauty-in-averageness literature that are inconsistent with pure fluency-based accounts. while aver- ageness has been found to predict beauty in a number of real-world categories, there are cases beyond the present table combined mixed effects models to predict measures of fluency from distance-from-the-bound, beauty, and category label measure b df t p typicality intercept . . <. *** distance . . . * beauty − . − . . beauty * category label . . . ** reaction time intercept . . <. *** distance − . − . <. *** beauty . . . beauty * category label − . − . . * b z p probability correct intercept . . <. *** distance . . <. *** beauty − . − . . beauty * category label . . <. *** note. table shows the model coefficients for each of the terms. these slopes (b) imply an increase of b in the measure of fluency for each one unit increase in either distance or beauty. the intercept gives the mean rating for each measure of fluency. category label is dummy coded such that student art show and art museum. thus, the coefficient for beauty corresponds to the beauty slope in the student art show category, and the coefficient for the beauty * category label interaction indicates the change in this beauty slope for the art museum category. *p < . **p < . ***p < . fig. typicality as a function of beauty. consistent with the theory- based view, more beautiful paintings are rated as more typical for the art museum category, but not for the student art show category psychon bull rev ( ) : – experiment where it does not. for example, typical spiders are not rated as the most attractive or beautiful (halberstadt, ), although typical dogs, fish, and wristwatches are (halberstadt & rhodes, ). this difference may be explained by our theories about these categories. our beliefs about spiders, as unpleasant and even dangerous, are more negative than our prior expectations about dogs and wrist- watches. similarly, student art shows are expected to contain less beautiful art than art museums. these findings are in line with a theory-based view, which would predict a rela- tionship between beauty and typicality only in positive categories or those affiliated with beauty, even though they are inconsistent with pure fluency-based accounts. these examples also suggest that the two views need not be mutually exclusive. depending on the domain and how rele- vant theories are to it, theory, similarity, or both effects could be manifested. unlike patterns of dots or simple drawings of wristwatches, artworks are complex, beauty relevant, and as- sociated with different cultural practices and personal experi- ences. as a result, we may have strong theories about artworks that shape our perception of their beauty, whereas featural similarity may exert a greater impact on our perception of simpler stimuli’s beauty in the absence of strong theories. in summary, we explored one aspect of beauty’s nature: its relationship to individuals’ theories and perceptions of cate- gories. our results suggest that beauty is not merely a reflec- tion of category structure, as is predicted by a similarity-based view. instead, the relationship between beauty and category structure may be more complex than can be captured by similarity alone. in judgments of real-world stimuli, beauty itself can influence the structure of categories, in line with a theory-based explanation. beauty remains mysterious; how- ever, we have made some progress here in understanding it. author note this work was supported by the national institutes of health (mh ), the air force office of scientific research (fa - - - ), the army research laboratory (w nf- - - ), and the national science foundation ( ). references asch, s. e. 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( ). attitudinal effects of mere exposure. journal of personality and social psychology, ( ), – . psychon bull rev ( ) : – is better beautiful or is beautiful better? exploring the relationship between beauty and category structure abstract method subjects materials design and procedure categorization task rating tasks results relationships among the basic variables similarity-based versus theory-based views of beauty category structure affects processing fluency and perceptions of typicality, but not beauty beauty contributes to typicality in the art museum condition discussion references arxiv:hep-ph/ v sep ar x iv :h ep -p h/ v s ep cern-th/ - shep - exclusive decays of beauty hadrons c.t. sachrajda theory division, cern, ch- geneva switzerland and physics department, university of southampton, southampton so bj, uk abstract the principal difficulty in deducing weak interaction properties from experi- mental measurements of b-decays lies in controlling the strong interaction effects. in this talk i review the status of theoretical calculations of the amplitudes for ex- clusive leptonic and semileptonic decays, in the latter case with special emphasis on the extraction of the vcb and vub matrix elements. invited lecture, presented at the workshop “beauty ‘ ”, rome, - june . http://arxiv.org/abs/hep-ph/ v introduction in this lecture i will review the status of theoretical calculations of exclusive b- decays. it is intended that this talk should complement those presented at this conference by n. uraltsev [ ] (theory of heavy quark physics), a. ali [ ] (rare b-decays) and m. gronau [ ] (cp -violation). the two main topics which will be discussed here are: i) leptonic decays in which the b-meson decays into leptons, e.g. b → τ ντ . these are the simplest to consider theoretically (see sec. ). their observation at future b-factories would have a significant impact on the phenomenology of beauty decays. ii) semileptonic decays in which the b-quark decays into a lighter quark + leptons. examples of such decays include b → (d or d∗) + lνl and b → (π or ρ) + lνl, which are being used to determine the vcb and vub matrix elements of the ckm-matrix (see sec. ). many of the theoretical issues concerning these decays are relevant also for rare decays, such as b → k∗γ. non-leptonic decays in which the b-meson decays into two or more hadrons, such as b̄ → π−d+, are considerably more complicated to treat theoretically, and with our current level of understanding require model assumptions. i will not discuss them further in this talk (see however the talk by gronau [ ]). in studying the decays of b-mesons, we are largely interested in extracting information about the properties and parameters of the weak interactions, and in looking for possible signatures of physics beyond the standard model. the most important theoretical problem in interpreting the experimental results, is to control the strong interaction effects which are present in these decays. this is a non-perturbative (and hence very difficult) problem, and is the main subject of this talk. the main theoretical tools that are used to quantify the effects are lattice simulations and qcd sum rules, combined with the formalism of the heavy quark effective theory (hqet) where appropriate. as with any problem in non-perturbative quantum field theory, the exploita- tion of all available symmetries is very important. for the case of heavy quark physics, the use of the spin-flavour symmetries that are present when the masses of the heavy quarks are ≫ Λqcd, leads to considerable simplifications (see refs. [ ] and [ , ] for recent reviews and references to the original literature). in partic- ular, as will be seen in the following sections, the use of heavy quark symmetries and the hqet is particularly helpful for b-decays. it is not appropriate in this lecture to present a detailed critical review of the systematic errors present in lattice simulations (see ref. [ ] for a recent review). since many of the results below are based on lattice simulations, it is, however, necessary to mention at least the main source of uncertainty present in the calcu- lations of quantities in b-physics. the number of space time points on a lattice is b− b ū l− ν̄ w figure : diagram representing the leptonic decay of the b-meson. limited by the available computing resources. one therefore has to compromise between two competing requirements: (i) that the lattice be sufficiently large in physical units to contain the particle(s) whose properties are being studied, i.e. the length of the lattice in each direction should be ≫ fm, and (ii) that the spacing between neighbouring lattice points, a, be sufficiently small to avoid errors due to the granularity of the lattice (called “lattice artefacts” or “dis- cretization errors” in the literature), i.e. a− ≫ Λqcd. much effort is currently being devoted to reducing the discretization effects by constructing “improved” (or even “perfect” [ ]) lattice actions and operators following the approach of symanzik [ ]. typical values of a− in current simulations are about – gev, i.e. the lattice spacings are larger than the compton wavelength of the b-quark, and the propagation of a b-quark on such lattices cannot be studied directly. the results presented below are obtained by extrapolating those computed directly for lighter quarks (with masses typically around that of the charm quark). in addition, calculations can be performed in the hqet and the results obtained in the infinite mass limit can then be used to guide this extrapolation. i should also add that, except where explicitly stated to the contrary, the results below have been obtained in the quenched approximation, in which sea-quark loops are neglected. this approximation is very gradually being relaxed, as computing resources and techniques are improved. the second non-perturbative method which is used extensively to compute amplitudes for b-decays is qcd sum rules [ ]. in this approach, correlation functions are calculated at intermediate distances, keeping a few terms in the operator product expansion (ope), and by using dispersion relations are related to spectral densities. the evaluation of the systematic uncertainties, such as those due to the truncation of the perturbation series and ope or to the specific models that are used for the continuum contribution to the spectral densities, is a very complicated issue; see refs. [ , ] and the papers cited below for any discussion of this important question. i now review the status of leptonic and semileptonic decays of b-mesons in turn. leptonic decays leptonic decays of b-mesons, see fig. , are particularly simple to treat theoreti- cally . the strong interaction effects are contained in a single unknown number, called the decay constant fb. parity symmetry implies that only the axial com- ponent of the v –a weak current contributes to the decay, and lorentz invariance that the matrix element of the axial current is proportional to the momentum of the b-meson (with the constant of proportionality defined to be fb): 〈 | aµ( ) | b(p)〉 = i fb pµ . ( ) knowledge of fb would allow us to predict the rates for the corresponding decays: Γ(b → lνl + lνl γ) = g f v ub π f bm l mb ( − m l m b ) ( + o(α)) , ( ) where the o(α) corrections are also known. in addition to leptonic decays, it is expected that the knowledge of fb would also be useful for our understanding of other processes in b-physics, particularly for those for which “factorization” might be thought to be a useful approximation. for example, in b–b mixing, the strong interaction effects are contained in the matrix element of the ∆b = operator: m = 〈b | b̄γµ( − γ )q b̄γµ( − γ )q | b 〉 . ( ) it is conventional to introduce the bb-parameter through the definition m = f bm bbb . ( ) in the vacuum saturation approximation (whose precision is difficult to assess a priori) bb = . it appears that bb is considerably easier to evaluate than fb, e.g. recent lattice results (for the matrix element m of the operator renormalized at the scale mb in the ms scheme) include b(mb) = . ( ) and . ( ) [ ] and . ( ) [ ]. thus it is likely that the uncertainty in the value of the matrix element m in eq. ( ) is dominated by our ignorance of fb. fds: since experimental results are beginning to become available for fds , i will start with a brief review of the decay constants of charmed mesons. many lattice computations of fd have been performed during the last ten years, and my summary of the results is [ ] fd = ± mev , ( ) for simplicity the presentation here is for the pseudoscalar b-meson. a parallel discussion holds also for the vector meson b∗. the rapporteur at the lattice conference summarized the results for the decay con- stants as fd ≃ fb ≃ gev ± % [ ]. using a normalization in which fπ+ ≃ mev. the value of the decay con- stant is found to decrease as the mass of the light valence quark is decreased (as expected), so that fds is – % larger than fd, fds = ± mev. as an example of the many lattice results which have been published for fds , i give here the two new ones presented at this year’s international symposium on lattice field theory. the milc collaboration found fds = ± ± ± mev, where the first error is statistical, the second an estimate of the systematic uncertainties within the quenched approximation, and the third an estimate of the quenching errors [ ]. the jlqcd collaboration found fds = ± + − mev, where the second error is systematic (within the quenched approximation) [ ]. these re- sults illustrate the fact that the errors are dominated by systematic uncertainties, and the main efforts of the lattice community are being devoted to controlling these uncertainties. it is very interesting to compare the lattice prediction of ± mev with experimental measurements for fds . the particle data book [ ] quotes the results fd+ < mev and fd+ s = ± ± ± mev wa ( ) fd+ s = ± ± ± mev cleo ( ) fd+ s = + − ± mev bes . ( ) more recently the cleo result has been updated [ ] (fd+ s = ± ± ± mev) and the e collaboration has found [ ] fd+ s = ± ± ± mev. combining the four measurements of fds from ds → µν decays, the rapporteur at this year’s ichep conference found [ ] fds = ± ± mev . ( ) in spite of the sizeable errors, the agreement with the lattice prediction is very pleasing and gives us further confidence in the predictions for fb and related quatnities. fb: for sufficiently large masses of the heavy quark, the decay constant of a heavy–light pseudoscalar meson (p ) scales with its mass (mp ) as follows: fp = a√ mp [ αs(mp ) − /β { + o(αs(mp ) ) } + o ( mp )] , ( ) where a is independent of mp . using the scaling law ( ), a value of about mev for fd would correspond to fb ≃ mev. results from lattice com- putations, however, indicate that fb is significantly larger than this and that the o( /mp ) corrections on the right-hand side of eq. ( ) are considerable. my summary of the lattice results is [ ] (see also footnote ): fb = ± mev . ( ) b d, d∗, π, ρ b c, u q̄ v –a figure : diagram representing the semileptonic decay of the b-meson. q̄ repre- sents the light valence antiquark, and the black circle represents the insertion of the v –a current with the appropriate flavour quantum numbers. the coefficient of the o( /mp ) corrections is found to be typically between . and gev. present lattice studies of heavy–light decay constants are concentrating on relaxing the quenched approximation, on calculating the o( /mp ) corrections in eq. ( ) explicitly, and on reducing the discretization errors through the use of improved actions and operators. the results obtained using qcd sum rules are in very good agreement with those from lattice simulations (see, for instance, ref. [ ] and references therein, and ref. [ ]). semileptonic decays for the remainder of this talk i will discuss semileptonic decays of b-mesons, considering in turn the two cases in which the b-quark decays semileptonically into a c-quark or a u-quark, see fig. . in both cases it is convenient to use space- time symmetries to express the matrix elements in terms of invariant form factors (i use the helicity basis for these as defined below). when the final state is a pseudoscalar meson p = d or π, parity implies that only the vector component of the v –a weak current contributes to the decay, and there are two independent form factors, f + and f , defined by 〈p (pp )|v µ|b(pb)〉 = f +(q ) [ (pb + pp ) µ − m b − m p q qµ ] + f (q ) m b − m p q qµ , ( ) where q is the momentum transfer, q = pb − pp . when the final-state hadron is a vector meson v = d∗ or ρ, there are four independent form factors: 〈v (pv )|v µ|b(pb)〉 = v (q ) mb + mv ǫµγδβ ε∗βpb γpv δ ( ) 〈v (pv )|aµ|b(pb)〉 = i(mb + mv )a (q )ε∗ µ − i a (q ) mb + mv ε∗·pb(pb + pv )µ + i a(q ) q mv ε ∗·pbqµ , ( ) where ε is the polarization vector of the final-state meson, and q = pb − pv . below we shall also discuss the form factor a , which is given in terms of those defined above by a = a + a , with a = mb + md∗ md∗ a − mb − md∗ md∗ a . ( ) . semileptonic b → d and b → d∗ decays b → d∗ and, more recently, b → d decays are used to determine the vcb element of the ckm matrix. theoretically they are relatively simple to consider, since the heavy quark symmetry implies that the six form factors are related, and that there is only one independent form factor ξ(ω), specifically: f +(q ) = v (q ) = a (q ) = a (q ) = [ − q (mb + md) ] − a (q ) = mb + md √ mbmd ξ(ω) , ( ) where ω = vb·vd. here the label d represents the d- or d∗-meson as appropriate. in this leading approximation the pseudoscalar and vector mesons are degenerate. the unique form factor ξ(ω), which contains all the non-perturbative qcd effects, is called the isgur–wise (iw) function. vector current conservation implies that the iw-function is normalized at zero recoil, i.e. that ξ( ) = . this property is particularly important in the extraction of the vcb matrix element. the relations in eq. ( ) are valid up to perturbative and power corrections. the theoretical difficulty in making predictions for the form factors lies in calcu- lating these corrections with sufficient precision. the decay distribution for b → d∗ decays can be written as: dΓ dω = g f π (mb − md∗) m d∗ √ ω − (ω + ) · [ + ω ω + m b − ωmbmd∗ + m d∗ (mb − md∗ ) ] |vcb| f (ω) , ( ) where f(ω) is the iw-function combined with perturbative and power correc- tions. it is convenient theoretically to consider this distribution near ω = . in this case ξ( ) = , and there are no o( /mq) corrections (where q = b or c) by virtue of luke’s theorem [ ], so that the expansion of f( ) begins like: f( ) = ηa ( + Λqcd mq + c Λ qcd m q + · · · ) , ( ) where ηa represents the perturbative corrections. the one-loop contribution to ηa has been known for some time now, whereas the two-loop contribution was evaluated this year, with the result [ ]: ηa = . ± . , ( ) where we have taken the value of the two loop contribution as an estimate of the error. the power corrections are much more difficult to estimate reliably. neubert has recently combined the results of refs. [ ]–[ ] to estimate that the o( /m q) terms in the parentheses in eq. ( ) are about − . ± . and that f( ) = . ( ) . ( ) in considering eq. ( ), the fundamental question that has to be asked is whether the power corrections are sufficiently under control. there are differing, passionately held views on this subject. the opinion of g. martinelli and myself is that the uncertainty in eq. ( ) is underestimated [ ]. the power corrections are proportional to matrix elements of higher-dimensional operators. these have either to be evaluated non-perturbatively or to be determined from some other physical process. in either case, before the matrix element can be determined a subtraction of large terms is required (since higher-dimensional operators in general contribute to non-leading terms). the “large” terms are usually only known in perturbation theory at tree level, one-loop level or exceptionally at two- loop level. therefore the precision of such a subtraction is limited. moreover the definition of the higher-dimensional operators, and hence the value of their matrix elements, depend significantly on the treatment of the higher-order terms of the perturbation series for the coefficient function of the leading twist operator (this series not only diverges, but is not summable by any standard technique). these arguments are expanded, with simple examples and references to the original literature, in ref. [ ]. considerable effort is being devoted at present to improving the theoretical control over power corrections. bearing in mind the caveat of the previous paragraph, the procedure for extracting the vcb matrix element is to extrapolate the experimental results for dΓ/dω to ω = and to use eq. ( ) with the theoretical value of f( ). see for example the results presented by artuso at this conference [ ]. having discussed the theoretical status of the normalization f( ), let us now consider the shape of the function f(ω), near ω = . a theoretical understanding of the shape would be useful to guide the extrapolation of the experimental data, and also as a test of our understanding of the qcd effects. we expand f as a power series in ω − : f(ω) = f( ) [ − ρ̂ (ω − ) + ĉ (ω − ) + · · · ] , ( ) where [ ] ρ̂ = ρ + ( . ± . ) + power corrections , ( ) and ρ is the slope of the iw-function. what is known theoretically about the parameters in eqs. ( ) and ( )? bjorken [ ] and voloshin [ ] have derived lower and upper bounds, respectively, for the ρ : < ρ < + Λ emin , ( ) where Λ is the binding energy of the b-quark in the b-meson, and emin is the difference in masses between the ground state and the first excited state. there are perturbative corrections to the bounds in eq. ( ) [ ], on the basis of which korchemsky and neubert [ ] conclude that . < ρ < . . ( ) values of ρ obtained using qcd sum rules and lattice simulations are presented in table . the theoretical results are broadly in agreement with the experimental measurements, e.g. in fig. we show the comparison of the lattice results from ref. [ ] with the data from the cleo collaboration [ ]. ρ method . ± . qcd sum rules [ ] . ± . qcd sum rules [ ] . ± . qcd sum rules [ ] . ± . qcd sum rules [ ] . + . − . + . − . lattice qcd [ ] table : values of the slope of the iw–function of a heavy meson, obtained using qcd sum rules or lattice qcd. recently, using analyticity and unitarity properties of the amplitudes, as well as the heavy quark symmetry, caprini and neubert have derived an intriguing result for the curvature parameter ĉ [ ]: ĉ ≃ . ρ̂ − . . ( ) this result implies that one of the two parameters in ( ) can essentially be eliminated, simplifying considerably the extrapolation to ω = . earlier attempts to exploit similar methods gave weaker bounds on the parameters. finally in this section i consider b → d semileptonic decays, which are beginning to be measured experimentally [ ] with good precision. theoretically the first complication is that the /mq corrections do not vanish at ω = . however, as pointed out by shifman and voloshin [ ], these corrections would figure : fit of the ukqcd lattice results for |vcb|f(ω) [ ] to the experimental data from the cleo collaboration [ ]. vanish in the limit in which the b- and c-quarks are degenerate. this leads to a suppression factor s = ( mb − md mb + md ) ≃ . ( ) in the /mq corrections, which reduces their size considerably. ligeti, nir, and neubert estimate the /mq corrections to be between approximately − . % to + . % [ ]. the /m q corrections for this decay have not yet been studied systematically. . semileptonic b → ρ and b → π decays in this subsection i consider the semileptonic decays b → ρ and b → π. they decays are currently being studied experimentally, with the goal of extracting the vub matrix element. heavy quark symmetry is less predictive for heavy→light decays than it is for heavy→heavy ones. in particular, as we have seen in the preceding subsection, the normalization condition ξ( ) = was particularly useful in the extraction of vcb. there is no corresponding normalization condition for heavy→light decays. heavy quark symmetry does, however, give useful scaling laws for the behaviour of the form factors with the mass of the heavy quark at fixed ω: v, a , a , f + ∼ m ; a , f ∼ m− ; a ∼ m . ( ) each of the scaling laws in eq. ( ) is valid up to calculable logarithmic correc- tions. figure : the form factor a (q ) for the decay b̄ → ρ+l−ν̄l. squares are measured lattice data, extrapolated to the b scale at fixed ω. the three curves and points at q = have been obtained by fitting the squared using the three procedures described in the text: constant (dashed line and octagon), pole (solid line and diamond) and dipole (dotted line and cross). several groups have tried to evaluate the form factors using lattice simula- tions [ ]–[ ] (for a review see ref. [ ]). the results that i will use for illustration are taken from the ukqcd collaboration, who have attempted to study the q dependence of the form factors. from lattice simulations we can only obtain the form factors for part of the physical phase space. in order to keep the discretization errors small, we require that the three-momenta of the b, π and ρ mesons be small in lattice units. this implies that we can only determine the form factors at large values of momentum transfer q = (pb − pπ,ρ) . fortunately, as we will see below, for b → ρ decays, this region of momentum space is appropriate for the extraction of vub. as an example, i show in fig. the values of the a form factor from ref. [ ]. these authors evaluate the form factors for four different values of the mass of the heavy quark (in the region of that of the charm quark), and then extrapolate them, using the scaling laws in eq. ( ), to the b-quark. the squares in fig. represent the extrapolated values, and as expected they are clustered at large values of q . in order to estimate them over the full kinematical range some assumption about the q behaviour is required. fig. also contains three such extrapolations in q , performed assuming that: i) a is independent of q (dashed line). the extrapolated value of a ( ) is denoted by an octagon, and the χ /dof is poor for this fit. ii) the behaviour of a (q ) satisfies pole dominance, i.e. that a is given by a (q ) = a ( ) ( − q /mn)n , ( ) with n = (solid line). a ( ) and m are parameters of the fit, but the value of m is in the range expected for the + bū resonance. the extrapolated value of a ( ) is denoted by the diamond. iii) the behaviour of a (q ) takes the dipole form ( ) with n = (dotted line). this is almost indistinguishable from the pole fit. the extrapolated value of a ( ) is now denoted by a cross. the χ /dof for the pole and dipole fits are both very good. the ukqcd collaboration [ ] comment that for b → ρ decays in particular, the fact that the lattice results are obtained at large values of q is not a serious handicap to the extraction of the vub matrix element. indeed they advocate using the experimental data at large values of q (as this becomes available during the next few years) to extract vub. to get some idea of the precision that might be reached they parametrize the distribution by: dΓ(b̄ → ρ+l−ν̄) dq = − g f |vub| π m b q λ (q ) a ( + b(q − q max) ) , ( ) where a and b are parameters to be determined from lattice computations, and the phase-space factor λ is given by λ(q ) = (m b + m ρ −q ) − m bm ρ . already from their current simulation the ukqcd collaboration are able to obtain a with good precision [ ] a = ± gev . ( ) although b is obtained with less precision, b = (− + − ) − gev− , ( ) the fits are less sensitive to this parameter at large q . the prediction for the distribution based on these numbers is presented in fig. , and the ukqcd collaboration estimate that they will be able to determine vub with a precision of about % or better. although, in this case, the difficulty of extrapolating lattice results from large values of q to smaller ones may not have significant implications for extracting physical information, this is not always the case. already for b → π decays, using results at large values of q restricts the precision with which vub can be extracted. this problem is even more severe for the penguin-mediated rare decay b → k∗γ, where the physical process occurs at q = . much effort is being devoted to this extrapolation, trying to include the maximum number of constraints from heavy figure : differential decay rate as a function of q for the semileptonic decay b̄ → ρ+l−ν̄l. squares are measured lattice data, solid curve is fit from eq. ( ) with parameters given in eqs. ( ) and ( ). the vertical dotted line marks the charm threshold. quark symmetry (as discussed above) and elsewhere [ ]. a simple example of such a constraint for b → π semileptonic decays is that at q = , the two form factors f + and f must be equal. similar constraints exist for other processes. an interesting approach to the problem of the extrapolation to low values of q has been suggested by lellouch [ ]. by combining lattice results at large values of q with kinematical constraints and general properties of field theory, such as unitarity, analyticity and crossing, he is able to tighten the bounds on form factors at all values of q . this technique can, in principle, be used with other approaches, such as sum rules, quark models, or even in direct comparisons with experimental data, to check for compatibility with qcd and to extend the range of results. ball and braun have recently re-examined b → ρ decays using light-cone sum rules [ ], extending the earlier analysis of ref. [ ]. consider, for example, the graph of fig. , which represents a contribution to the decay amplitude. for large heavy-quark masses and small q there are two competing contributions of the same order (e.g. o(m − / q ) for the form factor a ). the first one comes from the region of phase space in which the momentum of the gluon (g) is of the order of √ mbΛqcd, so that this contribution corresponds to small transverse separations and can be treated in perturbation theory (the non-perturbative effects are con- tained in the wave functions at the origin, i.e. in the decay constants). this is similar to the treatment of hard exclusive processes, such as the form factors of the pion and the proton at large momentum transfers. however, there is a second b ρ leptons w b u q̄ g figure : representation of a contribution to the semileptonic b → ρ decay. contribution in which the ρ-meson is produced in a very asymmetric configuration with most of the momentum carried by one of the quarks. in this case there are no hard propagators. for most other hard exclusive processes the “end-point” con- tribution is suppressed by a power of the large momentum transfer. although, in principle, for mq very large, the end-point is suppressed by sudakov factors [ ], this suppression is not significant for the b-quark. the end-point contribution has to be included and treated non-perturbatively, since it comes from the region of large transverse separations. this is the motivation for introducing light-cone sum rules [ ], based on an expansion of operators of increasing twist (rather than dimension). the non-perturbative effects are contained in the light-cone wave function of the ρ-meson, and the leading twist contribution to this wave function was recently re-examined in ref. [ ]. an interesting consequence of the analysis of the previous paragraph is a set of scaling laws for the behaviour of the form factors with the mass of the heavy quark at fixed (low) q , rather than at fixed ω as in eq. ( ). an example of fixed q scaling laws is: a ( ) Θ m / p = const( + γ/mp + δ/m p + · · ·) , ( ) where mp is the mass of the heavy pseudoscalar meson. the factor Θ contains the perturbative logarithmic corrections. some of the results of ball and braun are presented in fig. , where the form factors a , a and v are plotted as functions of q . the results are in remarkable agreement with those from the ukqcd collaboration, in the large q region where they can be compared. conclusions the principal difficulty in deducing weak interaction properties from experimental measurements of b-decays lies in controlling the strong interaction effects. these are being studied using non-perturbative methods such as lattice simulations or . . . t [gev ] (b) a ( t ) t [gev ] . . . (a) a ( t ) t [gev ] v ( t ) . . . (c) figure : results for the form factors a (q ), a (q ) and v (q ) for b → ρ semileptonic decays as a function of t = q [ ]. the curves correspond to the results obtained with light-cone sum rules by ball and braun [ ], and the points to the results from the ukqcd collaboration [ ]. qcd sum rules. considerable effort and progress is being made in reducing the systematic uncertainties present in lattice computations. although both the theoretical and experimental errors on the value of fds are still sizeable, it is nevertheless very pleasing that they are in agreement. it is also satisfying that the values of vcb extracted from exclusive and inclusive measurements are in good agreement. the theoretical uncertainties for the two processes are different, and the agreement is evidence that they are not signifi- cantly underestimated. it has been argued that b → ρ decays at large q , where the evaluation of the relevant form factors using lattice simulations is reliable, will soon provide a determination of vub at the % level or better [ ]. it will also be interesting to observe developments of the light-cone approach to these decays. many lattice computations of fb have been performed using static heavy quarks (mq = ∞), and serve as a very valuable check of the consistency of the extrapolation of the results obtained with finite heavy-quark masses. such checks have not been performed yet for many other quantities in b-physics; this is an important omission, which should be put right. this talk has been about the decays of b-mesons. detailed experimental and theoretical studies are also beginning for the Λb-baryon. for example, the first lattice results for the isgur–wise function of the Λb has been presented in ref. [ ]. acknowledgements it is a pleasure to thank nando ferroni and the other organizers of beauty ‘ for the opportunity to participate in such an interesting and stimulating meet- ing. i gratefully acknowledge many helpful and instructive discussions with pa- tricia ball, volodya braun, jonathan flynn, laurent lellouch, guido martinelli, matthias neubert, juan nieves, nicoletta stella and kolya uraltsev. i also ac- knowledge the particle physics and astronomy research council for their support through the award of a senior fellowship. references [ ] n.g. uraltsev, these proceedings. [ ] a. ali, these proceedings. [ ] m. gronau, these proceedings. [ ] m. neubert phys. rep. ( ) . [ ] m.a. shifman, hep-ph/ , lecture given at the theoretical advanced study institute, qcd and beyond, boulder, june . http://arxiv.org/abs/hep-ph/ [ ] h. wittig, hep-ph/ , to be published in the proceedings of the rd german–russian workshop on progress in heavy quark physics, dubna, russia, - may . 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[ ] n. stella (for the ukqcd collaboration), hep-lat/ ( ). http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-lat/ bul .tif psychological bulletin copyright by the american psychological association, inc. , vol. , no. , - - / /$ . doi: . // - . . . maxims or myths of beauty? a meta-analytic and theoretical review judith h. langlois, lisa kalakanis, adam j. rubenstein, andrea larson, monica hauam, and monica'smoot university o f texas at austin common maxims about beauty suggest that attractiveness is not important in life. in contrast, both fitness-related evolutionary theory and socialization theory suggest that attractiveness influences devel- opment and interaction. in meta-analyses, the authors evaluate these contradictory claims, demon- strating that (a) raters agree about who is and is not attractive, both within and across cultures; (b) attractive children and adults are judged more positively than unattractive children and adults, even by those who know them; (c) attractive children and adults are treated more positively than unattractive children and adults, even by those who know them; and (d) attractive children and adults exhibit more positive behaviors and traits than unattractive children and adults. results are used to evaluate social and fitness-related evolutionary theories and the veracity of maxims about beauty. i cannot say often enough how much i consider beauty a powerful and advantageous quality. socrates called it "a short tyranny," and plato, '~fhe privilege of nature." we have no quality that surpasses it in credit. it holds the first place in human relations; it presents itself before the rest, seduces and prepossesses our judgment with great authority and a wondrous impression. --montaigne, essays "beauty is truth, truth beauty," --that is all ye know on earth, and all ye need to know. --keats, ode on a grecian urn beauty has interested poets, philosophers, and scientists for centuries. indeed, the ancient greeks believed that there is a fundamental relation between beauty and positive qualities: those w h o are beautiful are also good (sappho, fragment no. ). "beauty is g o o d " was empirically tested in a seminal study by dion, berscheid, and walster ( ), who demonstrated that, e v e n in m o d e m times, human beings attribute positive qualities to attractive people and negative qualities to unattractive people. since this important study, much research has focused on the effects o f attractiveness, especially facial attractiveness, on, the attributions, impressions, and stereotypes o f strangers. these stud- ies primarily have investigated attributions made by college stu- dents about attractive and unattractive strangers based on a pho- tograph o f the face and, sometimes, minimal printed "background information" about the hypothetical individuals. this stranger- attribution literature has been summarized by earlier meta-analyses judith h. langlois, lisa kalakanis, adam j. rubenstein, andrea lar- son, monica hallam, and monica smoot, department of psychology, university of texas at austin. this work was supported by a grant from the national institute of child health and human development to judith h. langlois. we thank rebecca bigler, david buss, david cohen, alan feingold, george holden, don kalick, pam miller, william b. swann, and leslie zebrowitz for their helpful comments. correspondence concerning this article should be addressed to judith h. langlois, department of psychology, mezes / , university of texas at austin, austin, texas . electronic mail may be sent to langlois @mail.utexas.edu. (see, e.g., eagly, ashmore, makhijanl, & longo, ; feingold, b), which have c o n f m n e d the association between attractive- ness and many attributions o f positive characteristics. contrary to these findings o f a reliable relation between attrac- tiveness and attributions o f positive qualifies, however, are several age-old maxims and precepts holding that attractiveness either is not or should not be a significant factor in social interactions or behaviors. three maxims in particular are heard frequently: (a) beauty is in the eye o f the beholder, (b) never judge a book by its cover, and (c) beauty is only skin-deep. these maxims generally reflect received wisdom about the role o f attractiveness in human interaction. it is curious that these maxims are at such odds with the stranger-attribution literature. r e c e i v e d wisdom suggests that attractiveness is either not important at all or relevant only to first impressions but not as people b e c o m e more familiar with each other. perhaps it is the case that both are accurate: perhaps people make attributions about strangers based on attractiveness, but there are no practical effects o f being attractive or unattractive in real life. alternatively, perhaps the attribution literature does indeed generalize to actual interactions between people who are familiar with each other. assessing the relevance o f the maxims to every- day life and evaluating the mediating influence o f familiarity on attractiveness effects are important yet unaddressed issues. b e a u t y is i n t h e e y e o f t h e b e h o l d e r beauty is not judged objectively, but according to the beholder's estimation. --theocritus, the idyll according to the m a x i m beauty is in the eye o f the beholder, "different people have different ideas about what is beautiful" x defining attractiveness theoretically is a topic of great interest and controversy. until recently, empirical work proceeded without any con- ceptual or scientific definition of attractiveness: researchers simply de- fined people as attractive when raters agreed they were attractive. although this issue is beyond the scope of the current article, the interested reader is referred to cunningham ( ); farkas, munro, and kolar ( ); lang- lois and roggman ( ); and langlois, roggman, and musselman ( ), among others. maxims or myths of beauty (spears, , p. ) and, therefore, do not agree about who is and is not attractive. although this maxim is invoked both within and between cultures, it is believed to be true especially between cultures because different cultures presumably have very dissim- ilar standards of beauty (see, e.g., darwin, ; ford & beach, ). assessing the veracity of this maxim is important because without consensus in judgments of attractiveness, there can be no consistent effect of attractiveness on social judgments, interac- tions, or behavior. empirically, if beauty is only in the eye of the beholder, judgments of attractiveness should show little consis- tency among raters and, thus, low reliability coefficients. only one meta-analysis we know of has quantitatively evaluated the reli- ability coefficients of attractiveness judgments. feingold ( a) examined panels of raters from within the united states and canada and found a high level of agreement among adult raters. however, we do not know of any meta-analysis that has examined reliability coefficients of attractiveness judgments made by or about children nor do we know of any meta-analysis investigating agreement across raters of different ethnicities and cultures. n e v e r judge a b o o k b y its c o v e r judge not according to the appearance.--john : wilkinson ( ) defined this maxim as meaning "do not judge by externals" (p. ). the maxim urges people to disregard external appearance and to judge and treat others only on the basis of the "contents of the book." research has yet to determine whether this maxim accurately reflects judgments and treatment of others in actual interactions or whether the maxim represents an ideal. to determine if there is adherence to this maxim, we divided and operationalized it into two components: (a) judgments of others should not be based on their appearance, and (b) treatment of others should not be based on their appearance. if people conform to the maxim, then meta-analysis should find no signif- icant effects of attractiveness on judgments or treatment of others. attractiveness should be particularly unlikely to influence the interactions of people who know each other because such individ- uals have more than mere external appearance on which to base their judgments. as previously mentioned, numerous individual studies and a few meta-analyses have demonstrated the robust effects of attractiveness on the attributions or judgments people make of others based primarily on photographs. for example, eagly et al. ( ) quantitatively summarized the strength and generality of the physical attractiveness stereotype by examining studies in which participants inferred attributes of people whom they did not know and who were depicted in photographs. although such reviews are extremely important in consolidating the stranger-attribution literature, they ignore more ecologically relevant studies in which informed judgments of others are made following actual interactions. whether involving individ- uals known well or strangers encountered at the bank, grocery store, job interviews, or work, actual interactions are undoubt- edly more typical of daily life than making attributions about the characteristics of individuals depicted in photographs. al- though several individual studies have indicated that people do interact .differently with others based on attractiveness (dion, ; langlois, ritter, casey, & sawin, ; snyder, tanke, & berscheid, ; stewart, ; ), no meta-analysis is currently available to assess judgment and treatment of indi- viduals following actual interactions or to assess judgment and treatment of individuals people know. b e a u t y is o n l y s k i n - d e e p all the beauty of the world, 'tis but skin-deep. --ralph venning, the triumph of assurance according to this maxim, there is no necessary correspondence between external appearance and the behavior or personality of an individual (ammer, ). two meta-analyses have examined the relation between attractiveness and some behaviors and traits (feingold, b ; l. a. jackson, hunter, & hodge, ). fein- gold ( b) reported significant relations between attractiveness and measures of mental health, social anxiety, popularity, and sexual activity but nonsignificant relations between attractiveness and sociability, internal locus of control, freedom from self- absorption and manipulativeness, and sexual permissiveness in adults. feingold also found a nonsignificant relation between at- tractiveness and intelligence (r = . ) for adults, whereas l. a. jackson et al. found a significant relation for both adults (d = . overall, d = . once selected studies were removed) and for children (d = . ). these meta-analyses suggest that there may be a relation be- twe~n behavior and attractiveness, but the inconsistencies in re- suits call for additional attention. moreover, the vast majority of dependent variables analyzed by feingold ( b) and l. a. jackson et al. ( ) assessed traits as defined by psychometric tests (e.g., iq) rather than behavior as defined by observations of behaviors in actual interactions. thus, to fully understand the relations among appearance, behaviors, and traits, it is important to broaden the conception of behavior beyond that used by feingold and l. a. jackson et al. if beauty is only skin-deep, then a comprehensive meta-analysis of the literature should find no sig- nificant differences between attractive and unattractive people in their behaviors, traits, or self-views. theoretical m e c h a n i s m s in contrast to the three maxims, both general socialization and social expectancy theories (behavioral conflrmation and self- fulfilling prophecy) and fitness-related evolutionary theories (good genes, mate selection, and parental investment) predict that attrac- tiveness should and does have a significant impact on the judg- ments and treatment of others by perceivers and on the behaviors and traits of targets. although these perspectives were not origi- nally conceptualized to account for the origin or causal mechanism underlying attractiveness effects, both have been successfully in- voked to understand attractiveness effects, and a number of pre- dictions about attractiveness can be deduced from them (see, e.g., feingold ( ) also meta-analyzed behavioral and trait variables. however, the studies included in his meta-analysis were virtually identical to those included in feingold ( b) and are therefore not cited here as a third meta-analysis. langlois et al. barber, ; berscheid & walster, ; buss, , ; buss & schmitt, ; cunningham, druen, & barbee, ; eagly et al., ; feingold, a; l. a. jackson, ; d. jones, ; kalick, zebrowitz, langlois, & johnson, ; langlois, ; langlois & roggman, ; zebrowitz, ). although some aspects of these predictions have been evaluated by previous research, many important pieces of the theories have not yet been addressed. table provides a list of predictions suggested by the different theories that we elaborate on below. although we present them separately for purposes of clear exposition, we do not believe that any one theory or mechanism operates to the exclusion of the others. for example, within fitness- related evolutionary theory, several different evolutionary mecha- nisms are relevant, are not necessarily mutually exclusive, and may be operating simultaneously (gangestad & thornhiu, ; kirkpatrick, ). the usefulness of the systematic, modular approach we take here is in beginning to paint a more constrained picture of the domains, conditions, and developmental trajectories of the relevant evolutionary and social mechanisms and in under- standing where they do and do not intersect. socialization~social expectancy theories two core assumptions underlie socialization and social expect- ancy theories: (a) cultural norms and experiences influence the behavior of both targets and perceivers, and (b) social stereotypes create their own reality (see, e.g., langlois, ; snyder et al., ). these core assumptions map on to the three maxims about attractiveness. according to the first assumption, people should agree about who is and is not attractive within cultures because of cultural similarities in standards of attractiveness. in contrast, the theories predict lack of agreement in cross-cultural judgments of attractiveness because different cultures have different cultural standards of beauty (darwin, ; ford & beach, ). we evaluate agreement about target attractiveness both within and across cultures in our first set of meta-analyses (reliability). social stereotypes create their own reality through a multistep causal mechanism: (a) facial appearance elicits social stereotypes or expectations for the behavior and traits of attractive and unat- tractive targets, (b) these expectations are acted on by the perceiver in the form of differential judgments and treatment of attractive and unattractive targets, (c) differential judgment and treatment cause the development of differential behavior and traits in attrac- tive and unattractive targets, and (d) attractive and unattractive targets internalize differential judgment and treatment and even- tually develop differential behavior and self-views (for detailed discussions, see darley & fazio, ; and zebrowitz, ). the stranger-attribution literature and meta-analyses of it have f'lrmly established the existence of the "beauty is good" stereotype (see, e.g., adams & crane, ; berscheid & walster, ; dion, ; downs & harrison, ; eagly et al., ; fein- gold, b; langlois, ; ritter, casey, & langlois, ; snyder, berscheid, & glick, ). at least among strangers, attractiveness clearly elicits differential expectations for the be- havior and traits of attractive and unattractive targets. in our second set of meta-analyses (judgments), we examine studies in table predictions derived from social expectancy and fitness-related evolutionary theories prediction social mate selection theory good genes differential parental solicitude reliability of judgments within-culture agreement yes yes yes yes across-culture agreement no yes yes yes gender differences yes yes no no age differences yes ncp no ncp judgment and treatment differential judgment yes yes for adults yes yes for children gender differences yes yes for adults no no age differences yes ncp no ncp differential treatment yes yes for adults yes yes for children gender differences yes yes for adults no no behavior/trait differences yes yes for adults yes yes attractiveness is honest indicator of no yes for women yes yes fitness gender differences yes no no no age differences yes ncp no ncp differential self-perceptions yes ncp ncp ncp gender differences yes no no no age differences yes ncp no ncp causality judgment/treatment causes behavioral/ yes no no no trait differences behaviors/traits cause judgment and no yes yes yes treatment note. ncp = no clear prediction. maxims or myths of beauty which participants make informed judgments of attractive and unattractive targets following actual interaction or on the basis of role relationships (e.g., real teachers and their students), thereby extending results from the stranger-attribution literature to more ecologically valid situations. stereotypes and differential expectations about attractive and unattractive people also cause differential treatment of them ac- cording to social theory. in our third set of meta-analyses (treat- ment), we examine whether attractive and unattractive people are actually treated differently, especially by those who know them. finally, the theories hold that attractive and unattractive targets come to behave differently and develop different traits as a func- tion of differential judgment and treatment. our fourth set of meta-analyses (behavior/traits) reveals whether or not attractive and unattractive people behave differently and possess different traits. confirmation of these core assumptions is necessary for social theories to unambiguously explain attractiveness effects. however, several ancillary premises regarding age and gender differences would provide further support for the theories. first, age should influence the reliability of attractiveness ratings because, relative to younger judges, older judges have internalized societal, stan- dards of attractiveness. second, because many interactions be- tween adults and children involve socialization in which adults deliberately encourage some behaviors and discourage others, attractiveness should have more opportunities to influence the judgments and treatment of child than adult targets. thus, these perspectives should predict that attractive and unattractive children will receive more differential treatment and judgment than will adults. third, the accounts should predict age differences in tar- gets' behaviors and traits as a result of cumulative socialization. if behavioral differences result from differential treatment based on attractiveness, as assumed by the theories, behavioral differences as a function of attractiveness should not be evident very early in life yet, as children are exposed to more socialization effort and as a result of cumulative differential judgment and treatment, should become increasingly present with age. analyses examining attrac- tiveness effects for both children and adults are required to eval- uate these age-related ancillary premises of social theory and are performed below. in addition to predictions about age differences in the impor- tance of attractiveness, socialization and social expectancy theories make ancillary predictions about gender differences in the impor- tance of attractiveness. because human culture values attractive- ness more in females than in males, agreement about the attrac- tiveness of females should be greater than agreement about males, and females should experience more differential judgment and treatment based on attractiveness than males (hatfield & sprecher, ; l. a. jackson, ; zebrowitz, ). moreover, the effects of attractiveness on behaviors, traits, and self-views should be larger for females than males because females receive more differential judgment and treatment as a function of their attrac- tiveness. to evaluate these predictions, we examine gender differ- ences in all our analyses. fitness-related evolutionary theories fitness-related evolutionary theories (human mate selection, good genes, differential parental solicitude) posit that morpholog- ical characteristics such as attractiveness are honest indicators of fitness, health, quality, and reproductive value, and, therefore, that attractiveness is important in human interactions (barber, ; buss & schmitt, ; daly & wilson, ; gangestad & thorn- hill, ; symons, ; thornhill & gangestad, ). all three perspectives agree about the necessity of one a priori condition: because humans have evolved universal standards of attractive- ness based on clues to health and reproductive fitness, perceivers both within and across cultures should consistently detect and recognize attractiveness. other predictions about attractiveness differ across mechanisms and are described below. mate selection mate selection is the most commonly invoked evolutionary mechanism offered to explain attractiveness effects in both hu- mans and animals. a central tenant of mate-selection theory is that attractiveness is differentially important for the two sexes (anders- son, ; buss, , ; buss & barnes, ; buss & schmitt, ; g. f. miller, ; symons, ). with most nonhuman species, it is the male for whom attractiveness and "showiness" is more important. peacock feathers, turkey snoods, and colorful cichlid bellies in males are all assumed to have evolved as sexual enticements for females. however, with humans, it is almost always the female for whom attractiveness and show- iness is more important. thus, according to human mate-selection theory, men seek attractive women because attractiveness signals youth and reproductive fitness (buss, , ; thornhill, ). in contrast, women seek men with resources, rather than attractiveness, because such men are able to provide for offspring (see, e.g., buss, ). because this review is concerned with how attractiveness affects human development and interaction, our discussion of mate-selection theory focuses on humans (see, e.g., buss, ). in humans, because attractiveness is especially important as an indicator of reproductive fitness in women, the reliability of at- tractiveness ratings should be higher when judging females than when judging males, especially as evaluated by male perceivers (l. a. jackson, ). this prediction is examined by our reliabil- ity analyses. mate-selection research often focuses its predictions on pref- erences rather than behaviors (see, e.g., buss, ). however, because "mate choice is the behavioral outcome of mate pref- erences" (g. f. miller, , p. ), there should be some correspondence between preferences and behavior. therefore, because men prefer and seek attractive women, men should also judge and treat them more positively. because women favor men with resources more than merely attractive men, attrac- tiveness should be more important in how men judge and treat women than in how women judge and treat men (buss & barnes, ; buss & schmitt, ; l. a. jackson, ). we evaluate these predictions in our analyses of judgment and treatment. in contrast to the gender difference predictions for reliability, judgments, and treatment, mate-selection theory predicts no gen- der differences in the importance of attractiveness for most target langlois et al. behaviors and traits. rather, the theory predicts that initially unrelated traits coevolve because of assortative mating (buss, ; g. f. miller, ). thus, attractive women tend to choose intelligent males because such mates have the ability to acquire resources. offspring of both sexes then tend to inherit both char- acteristics, attractiveness and intelligence. therefore, both attrac- tive male and female offspring might be expected to be more intelligent than unattractive male and female offspring. such a view would be supported if we find no gender differences as a function of attractiveness in our behavior/traits analyses. finally, unlike socialization theory, mate selection theory makes no predictions regarding the importance of attractiveness for chil- dren. because young children are not involved in selecting a mate, this mechanism is not designed to explain children's behavior. good genes good-genes theory predicts that attractiveness should be mean- ingful in human interactions because attractiveness accurately ad- vertises health, quality, and heterozygosity (barber, ; gang- estad & buss, ; gangestad & thornhill, ; shackelford & larsen, ; thornhill, ; thornhill & gangestad, ; but see kalick et al., , for an alternative). thus, good-genes theory should predict differential judgment and treatment as a function of attractiveness because perceivers have evolved to prefer attractive people for their good health. the theory also should predict be- havioral differences in targets as a function of attractiveness be- cause attractiveness signals health, fitness, and quality. in contrast, the theory should predict no differences in behaviors unrelated to status and fitness (e.g., attitudes). differential judgment and treat- ment should be responses to (rather than causes of, as per social theory) these preexisting differential behaviors and traits of attrac- tive and unattractive individuals. in addition, because good health is critical to survival, attrac- tiveness should be equally relevant and important to both sexes (thiessen, ; thornhill & gangestad, ), a prediction that explicitly disagrees with socialization and social expectancy the- odes, as well as with mate-selection theory. similarly, because good health is important for all ages, attractiveness should be as important for children as for adults. this prediction again contrasts sharply with socialization and social expectancy theories, which regard behavioral differences as the result of cumulative social- ization. we evaluate these competing predictions in our behavior/ trait analyses. differential parental solicitude differential parental solicitude theory (a derivative of trivers's [ ] parental investment theory) conjectures that, to enhance their own reproductive success, parents invest differently in chil- dren depending on each child's fitness, quality, and reproductive potential (buss, ; daly, ; daly & wilson, , ). parents and other adults should allocate more energy, resources, attention, and care to higher quality offspring (mann, ; scrim- shaw, ). thus, if attractiveness is an indicator of quality, adults should invest more in attractive than unattractive children and, presumably, treat attractive children more favorably than unattractive children (barden, ford, jensen, rogers-salyer, & salyer, ; buss, ; field & vega-lahr, ; langlois et al., ). second, as with good-genes theory, differential parental solici- tude theory assumes that differences in health and quality should be manifested by differences in behavior exhibited by attractive and unattractive children and adults. thus, attractive individuals should possess more positive behaviors and traits than do unat- tractive individuals. third, because the theory is focused on adults' treatment of children, it places more importance than the other fitness-related evolutionary theories on differential treatment of children. by this logic, attractiveness is perhaps even more important for children than for adults, but the theory does not make any explicit predic- tions about age differences in the importance of attractiveness. finally, because the theory assumes that attractiveness is an equally valid indicator of health and quality in boys and girls, no gender differences would be expected in how boys and girls are judged and treated as a function of attractiveness (daly & wilson, ). purpose this article has three primary goals. the first goal is to extend knowledge of attractiveness effects beyond stranger-attribution paradigms to determine the extent to which attractiveness influ- ences daily lives and real interactions. the second goal is to examine the contradiction between common knowledge, as exem- plified by the three maxims, and empirical fmdings about facial attractiveness. the third goal is to use extant research to evaluate the current status of socialization/social expectancy theory and fitness-related evolutionary theory as theoretical accounts of at- tractiveness effects. although no single theory is likely to be uniformly supported or disconfumed, our hope is that the review will highlight areas of strongest support and, more importantly, will show where future research is needed to comprehensively evaluate the different theoretical perspectives. to accomplish these goals, we conducted a variety of meta- analyses. four meta-analyses of attractiveness reliability coeffi- cients evaluated interrater agreement about attractiveness, both within and across cultures. two met/l-analyses summarized re- search investigating global but informed evaluations of attractive and unattractive people, and two meta-analyses summarized stud- ies of differential treatment of attractive and unattractive people. three meta-analyses evaluated assessments of behavior and per- sonal characteristics as a function of attractiveness. finally, our analyses assessed whether the effects of attractive- ness apply to some groups more than to others. because of the gender and age predictions made by the different theories, we evaluated the moderating influences of gender and age on the although the theory at first glance seems to predict that attractiveness should be more important in the dating and sexual experiences of women than in those of men, it is not possible to make such a straightforward prediction. first, most men may not be able to successfully date very attractive women and thus may not ask them out (buss & schmitt, ). furthermore, men may have less stringent standards for attractiveness when seeking a short-term mate than when seeking a long-term mate (buss, ; buss & schmitt, ), and the particular strategy used by men in most of the retrieved studies cannot be determined. maxims or myths of beauty e f f e c t s o f a t t r a c t i v e n e s s . a l t h o u g h t h e r e a r e m a n y e m p i r i c a l s t u d - i e s a b o u t t h e i m p o r t a n c e o f a t t r a c t i v e n e s s f o r c h i l d r e n ( s e e , e . g . , d i o n , ; h i l d e b r a n d t & f i t z g e r a l d , ; l a n g l o i s & s t e p h a n , ), o u r s is t h e f i r s t m e t a - a n a l y s i s to i n c l u d e t h e m in a c o m p r e - h e n s i v e a n a l y s i s . m e t h o d retrieval of studies we began by examining the adult and child attractiveness literature obtained from a p a databases (psyclit, psycinfo), cash's ( ) anno- tated bibliography, and the eric database o f published, unpublished, and conference papers using key terms beauty, facial attractiveness, and phys- ical attractiveness. we also examined every relevant article from the reference sections o f all retrieved articles. this search resulted in obtaining references from through june . because there are many forms o f attractiveness and our primary interest was in objectively rated facial attractiveness within the normal distribution, we excluded studies in which the face was not available for assessment (body attractiveness, e.g., singh, ; vocal attractiveness, e.g., zucker- man & driver, ; grooming, e.g., mack & rainey, ) or if the study instructed judges to evaluate a different type o f attractiveness (sexual attractiveness, e.g., townsend & wasserman, ; self-evaluations o f attractiveness, e.g., n. cavior & dokecki, ), if the study measured another variable such as popularity but labeled the variable as attractive- ness (e.g., krantz, ), if the study confounded attractiveness with other variables (e.g., targets were selected to be both attractive and high in self-monitoring, snyder et al., ), or if the study compared facially disfigured targets to nondisfigured targets (e.g., field & vega-lahr, ). because we wanted to understand the role o f attractiveness in actual interactions, we excluded studies if they were pure attribution experiments (i.e., a study in which behavioral, trait, or personality attributions are made only by strangers and based solely on a photograph as per the studies included in eagly et al., ), if they failed to report useable statistics; if the unit o f analysis was more than a single individual (e.g., if dyads were analyzed together, clark & ayers, ), if variables were curvilinear and it was not clear that either extreme was positive or negative, or if we could not place the variable into a meaningful category (e.g., there was only one study o f child self-perceived traits, leruer, delaney, hess, jovanovic & von eye, ). from an initial sample o f over , empirical articles, we obtained a final data set o f useable effect sizes with some studies contributing more than one independent sample. to control for the possibility that our analysis overestimated the effect o f attractiveness by excluding studies we did not retrieve (i.e., the file-drawer problem, rosenthal, ), we com- puted the fail-safe n for each analysis (hedges & olkin, ). this statistic determines the number o f additional nonsignificant effect sizes necessary to reduce the effect sizes we report to null differences between attractive and unattractive groups. the results o f these fail-safe analyses indicate how resistant the findings are to the file-drawer problem and highlight which results, if any, should be interpreted with caution. description o f and assignment to categories the three maxims provided the initial conceptual basis for our catego- rization o f effect sizes. we examined five overall categories for adults and four overall categories for children: reliability o f attractiveness ratings, judgment, treatment, behavior/traits, and (for adults only) self-perceptions. within each o f these categories, we created subcategories by grouping conceptually similar variables. whenever possible, we constructed parallel subeategories for adults and children, but often the dependent variables examined for children did not correspond to those investigated for adults. reliability all reliability coefficients o f attractiveness ratings from retrieved studies were analyzed. the vast majority o f these studies asked raters to evaluate attractiveness from photographs (generally these raters were not the same participants analyzed for judgment or treatment); the remaining studies asked raters to evaluate attractiveness in situ or from videotapes. in almost all cases, judges used either a likert-type scale or rank orders to evaluate . attractiveness. we were interested in whether children would evaluate attractiveness similarly to adults, whether raters o f different ethni¢ity would evaluate attractiveness similarly when residing in similar cultures with similar exposure to media standards of beauty, and whether raters o f different ethnicity within different cultures and presumably different media expo- sure would evaluate attractiveness similarly. thus, four analyses were performed to evaluate: (a) adult within-culture, within-ethnic agreement, including only studies in which adults residing in the same culture were rated by others o f the same ethnicity as the targets; (b) child within-culture, within-ethnic agreement, including only studies in which children residing in the same culture were rated by others o f the same ethnicity as the targets; (c) adult within-culture, cross-ethnic agreement, in which correlations among raters residing within the same culture but from different ethnic groups were analyzed (e.g., african americans judging european ameri- cans); and (d) adult cross-cultural, cross-ethnic agreement, in which cor- relations among raters residing in different countries and from different ethnic groups were analyzed (e.g., koreans judging african americans). we located insufficient numbers o f studies o f children from different ethnic groups from either their own or other cultures, precluding analyzing cross-ethnic reliability for children. see appendix a for information about studies included in the meta-analyses o f cross-cultural and cross-ethnic agreement and appendix b for studies included in the within-culture, within-ethnic analyses. judgment and treatment assignment o f effect sizes to both this set o f analyses and to the behavior/traits analyses was more complex than assignment to our reliabil- ity analyses because o f the diversity o f research measures found in re- trieved studies. the studies retrieved for judgment, treatment and behavior/ traits used standardized and unstandardized measures, global and moleculal" measures, ratings by experts and nonexperts, and self- versus other-reports o f behaviors, traits, and treatments. separating different types o f measures that seemingly assessed the same construct but in fact had significantly different conceptual foundations was necessary to success- fully differentiate measures o f judgment, treatment, and behavior. for example, friendliness could be assessed by global judgments made casually by a rater or by molecular behavioral counts o f smiling made by a highly trained observer. although both may have been construed as indexes o f the construct "friendliness" in different studies, these two measures have important conceptual differences. distinguishing between global and mo- lecular measures is crucial because global ratings and judgments o f indi- viduals can be influenced by the "beauty is good" stereotype: global ratings of friendliness reflect opinions o f the rater as much as, if not more than, they reflect the behavior o f the target (ritter & langlois, ). therefore, we assigned global measures to the judgment category. in contrast, molecular measures correspond closely to actual behaviors (ritter & langlois, ) and thus were assigned to behavior/traits. descriptions o f the particular types o f measures included in each category created for judgments, treatment, and behavior/traits are provided below. judgment. this category was conceptualized as informed opinions about attractive and unattractive targets. the category o f judgment was thus defined as global ratings (e.g., friendliness, intelligence) made by others based on actual incidents o f observable behavior. studies investigating judgments about children typically consisted o f peer and adult ratings o f behavioral traits and personality characteristics. langlois et al. subcategories were academic/developmental competence, adjustment, in- terpersonal competence, and social appeal. studies examining j u d g m e n t s about adults were typically global j u d g m e n t s o f behavioral traits and personality characteristics m a d e by other adults. subcategories were ad- justment, interpersonal competence, occupational competence, and social appeal. see table for definitions and examples o f each subcategory and appendixes c and d for information about studies included in the meta-analysis. treatment. this category was defined as observable actions having or thought to have actual impact on a target. the crucial criterion for inclusion was that the measure m u s t reflect actions toward a target by an agent. for example, actions such as punishing an attractive or unattractive child or smiling directed toward an attractive or unattractive target were included in this category. studies investigating treatment o f children focused on the actions o f peers, teachers, and caregivers. subcategories were attention/caregiving, designation o f academic ability, negative interaction, and positive inter- action. studies examining treatment of adults typically included actions o f both adults and children in laboratory and naturalistic settings. subcatego- ries were attention, help giving/cooperation, negative interaction, positive impression m a n a g e m e n t , positive interaction, and reward (see table and appendixes e and f). behavioral differences to separate conceptually distinct types o f measures, we created two overall categories for behavioral differences: behavior/traits and self- perceived traits. all molecular measures o f behavior were classified as behavior/traits (ritter & langlois, ). standardized psychometric mea- sures o f traits (e.g., iq tests) were also assigned to this category because they h a v e been validated as reasonably accurate measures o f their con- structs. furthermore, because experts (e.g., mental health professionals) who m a k e behavioral a s s e s s m e n t s in their area o f expertise should be unbiased and provide measures that are approximately equivalent in va- lidity to standardized measures, we included s u c h measures in behavior/ traits. finally, we included m e a s u r e s o f popularity in behavior/traits because peers are, by definition, experts in j u d g i n g w h o m they like. for children, behavior/traits were generally measured by observational or sociometric data and by standardized tests. approximately % o f the measures were based on observation o f actual behavior. subcategories included adjustment, intelligence/performance, and popularity. for adults, behavior/traits were generally measured through observational studies, standardized tests, or molecular a s s e s s m e n t s o f interaction behavior. ap- proximately % of the measures were based on observations o f actual behavior. subcategories were extraversion, intelligence, occupational success, mental health, physical health, popularity, self-confidence/self- esteem, social skills, traditional attitudes, dating experience, and sexual experience (see table and appendixes g and h). in addition to using molecular measures, standardized measures, or behavioral/trait a s s e s s m e n t s by experts, m a n y studies used global, unstand- ardized self-reports o f behaviors and traits. w e analyzed these m e a s u r e s because differential j u d g m e n t s and treatment m a y lead both to differential behavior and to differential self-views as a function o f attractiveness (snyder e t a l . , ). in addition, s u c h measures m a y illustrate interesting differences between attractive and unattractive individuals. however, be- cause unstandardized self-reports are less objective than standardized mea- sures o f traits and behaviors, we created a separate category for them. self-perceptions included two subcategories for adults, competence and mental health. w e were not able to analyze self-perceptions for children because only a single study representing this category was retrieved (see table and appendix i). classification decisions e a c h potentially r e l e v a n t article w a s r e v i e w e d by one o f u s a n d t h e n p r e s e n t e d to at least three others w h o were not familiar with the results o f t h e s t u d y a n d w h o decided w h e t h e r the s t u d y m e t i n c l u s i o n criteria. t h u s , k n o w l e d g e o f w h e t h e r or not a s t u d y f o u n d a relation b e t w e e n the d e p e n d e n t variable a n d attractiveness could n o t i n f l u e n c e the d e c i s i o n to include or e x c l u d e it. e a c h d e p e n d e n t variable was identified as r e p r e s e n t i n g one o f the s u b c a t e g o r i e s w i t h i n j u d g m e n t , treatment, be- havior/traits, or self-perceptions. b e c a u s e we e s t a b l i s h e d clear c o d i n g criteria that left little r o o m for d i s a g r e e m e n t , there was a l m o s t c o m p l e t e c o n s e n s u s a m o n g u s r e g a r d i n g overall category classification. h o w - ever, in a few cases, there was not total c o n s e n s u s about what subcat- e g o r y was m e a s u r e d by a particular d e p e n d e n t variable (e.g., is order o f s p e a k i n g in a group interaction a m e a s u r e o f social skills or extraver- sion?). w e u s e d the conceptual definition p r o v i d e d by the original author(s) w h e n available. w h e n this was n o t available, we d i s c u s s e d to c o n s e n s u s . effect sizes were coded so that a larger effect size indicated that attractive individuals received comparatively more treatment or had more o f a particular trait or behavior than unattractive individuals. to ensure accuracy, at least two o f u s verified effect size and variable coding, as well as data entry. description of moderator variables w e coded characteristics of both the study participants and the studies themselves as potential moderators o f attractiveness effects. participant characteristics included gender and age. study characteristics included year o f publication, sample size, and the degree o f familiarity between the target and the j u d g e or the person behaving toward the target. furthermore, because the type o f attractiveness ratings u s e d is o f central importance to our findings, we created a n u m b e r o f moderator variables to explore effects o f methodological differences on our findings. first, we c o d e d whether the attractiveness ratings were obtained from photographs or videotapes, or were done in situ (method: photo vs. video vs. in situt). second, we coded whether the ratings were m a d e from the face alone or whether the stimulus included any additional information, s u c h as clothing (type: facial only vs. additional information). third, we coded whether the study treated attrac- tiveness as a dichotomous variable or whether the study treated attractive- ness as a continuous variable (range: dichotomous vs. continuous). finally, we coded whether the raters w h o m a d e the attractiveness ratings also m a d e j u d g m e n t s o f other behaviors and traits or whether the attractiveness raters were a separate, independent panel o f judges. inclusion of this variable was important because the "beauty is good" stereotype m a y bias raters evalu- ating both physical attractiveness and behavior (raters: independent vs. nonindependent). w e were unsure where to assign grades. do grades reflect treatment by a teacher and belong in designation o f academic ability? or do they reflect attributes o f the individual such as intelligence/performance and belong in behaviors/traits? for high school and college students, w h o often are in larger classes and who take multiple-choice tests, grades probably reflect teachers' stereotypes less than they reflect actual ability o f the student. therefore, we assigned grades o f h i g h school and college students to behavior/traits. however, the issue for y o u n g children is less clear. o n the one hand, m o s t so-called grades in elementary school are global assess- m e n t s o f excellent, satisfactory, or unsatisfactory rather than actual grades. furthermore, s o m e research h a s suggested that teacher expectations influ- ence grade assignments to elementary school children (jussim & eccles, ). therefore, to be conservative in assessing children's ability, we initially assigned grades to differential treatment. however, we also ana- lyzed the data with grades of y o u n g children assigned to behavior/traits, so the reader can decide for her- or himself. see note . because there were only a few studies that u s e d attractiveness ratings made in situ, we collapsed video and in situ into a single category. maxims or myths of beauty t a b l e category and subcategory definitions and examples category and subcategory definition and examples judgment informed opinions about attractive and unattractive targets. defined as global ratings made by others based on actual incidents of observable behavior. children academic/developmental competence adjustment interpersonal competence social appeal adults adjustment interpersonal competence occupational competence social appeal treatment children attention/caregiving designations of academic ability negative interaction positive interaction adults attention help-giving/cooperation negative interaction positive impression management positive interaction reward behavior/traits children adjustment intelligence/performance popularity adults dating experience sexual experience extraversion intelligence occupational success mental health physical health popularity self-confidence/self-esteem social skills traditional attitudes self-perceived traits adults competence mental health judgments of academic performance, skills, intelligence, alertness, acting grown up. judgments of comfort in social settings, confidence, number of fears, aggression. judgments of success in social situations, leadership, social power, success in disputes, fairness. judgments of social desirability, sociability, temperament, getting along with others, positive mood. judgments of comfort, ratings of anxiety, loneliness, adjustment in clinical settings. judgments of success in social situations, assertiveness, conversational skitls, general social skill. judgments of job performance, competence, motivation for success, suitability as potential employee. judgments of social desirability, friendliness, gracefulness, likeability. observable actions having or thought by the agent to have an actual impact on target. visual attention and caregiving. grades and designations of ability assigned to pre-high school age children by teachers. punishment, negative feedback, rejection, aggression. prosocial behavior, social play, sharing, instructional assistance, positive reactions. visual and social attention. providing assistance to targets by mailing letters, signing petitions, giving directions, financial help. punishment, unfriendly behavior, length of prison incarceration and jail sentences, avoidance, deception. positive or intimate self-disclosure, help-seeking. prosocial behavior, positive emotion, honesty, smiling, proximity-seeking, acceptance. providing positive outcomes or support for performance, recommendations for hiring, nominations for monetary reward, number of election votes of political candidates. molecular measures, standardized measures, and expert assessments of behavior and traits. mental health, self-esteem, social skills; freedom from juvenile delinquency, depression, and anxiety. iq and achievement: iq tests (act, iowa test of basic skills, vocabulary, gpa of high school students). social standing in the peer group, popularity, positive peer relations, reciprocated friendships, peer acceptance. frequency of dating, lack of dating anxiety, dating assertiveness. frequency of sexual experience, number of sex partners. assertiveness/shyness in social situations assessed by personality inventories, conversational behavior, assertiveness. iq and academic performance (iq tests, gpa of college students, sat scores, honors). occupational success and advancement in the workplace, income, military rank. mental health and well-being; freedom from loneliness, narcissism, type a behavior, and depression; emotional stability; social functioning. blood pressure, health center visits, freedom from substance abuse. social standing, liking, sorority membership, interpersonal attraction, number of social interactions. positive self-view, locus of control, ego functioning, positive self-disclosure. comfort and competence in social situations, empathy, influence, smiling, persuasive effectiveness, facial expressiveness, freedom from social anxiety and reticence. conservatism and attitudes toward social roles assessed by sex role inventories, social conformity, support for the women's movement. unstandardized self-reports of traits. global self-evaluations of intelligence, success, persuasiveness, social competence, social desirability. self-perceptions of risk of mental disorders, susceptibility to mental illness, happiness, affect balance, enjoyment of pleasant events, satisfaction with life domains, freedom from stress. thus, we assessed reliability as a function of the following moderators: target gender (we did not code the gender of the attractiveness raters because the majority of studies either did not report the appropriate statistics or analyzed both genders together), method, year of publication, and sample size. we were unable to analyze rater age because raters were almost always adults and there was insufficient variance to make this a meaningful analysis. for the other categories, we coded target gender, target age (for children only; almost all studies of adults involved only college students), year of publication, sample size, type, range, raters, and familiarity (except for behaviors/waits, which did not involve a target). in addition, for the judgment and treatment categories, agent gender and agent age were coded. langlois et al. data analyses effect sizes using dstat (b. t. johnson, ), we first calculated one effect size for the overall category (e.g., treatment), collapsing across all subcatego- des. because each sample o f participants should contribute only one entry per analysis (hedges & olkin, ), multiple effect sizes obtained from the same participants were converted to z scores, averaged, and the average converted back to an r, resulting in only one effect size per sample (rosenthal, ). when this process necessitated averaging ns o f slightly different sizes, usually due to participant attrition on certain measures but not others (e.g., leinbach & fagot, ), we used the smallest n to be most conservative. most often, averaging was performed within individual studies, but on a few occasions, separate studies reported statistics from the same sample (e.g., jovanovic, lerner, & lerner, ; lerner et al., , ), and then the rs from more than one study were averaged. second, we calculated separate effect sizes for each subcategory o f dependent variables (e.g., social skills). at the subcategory level, multiple measures o f the same construct obtained from the same participants were averaged, again resulting in only one effect size per sample in each subcategory. for the reliability analyses, most studies provided correlational statistics that could be used directly. because different studies reported different types o f reliability coefficients, we converted the different coefficients (e.g., k e n d a l r s tau) to an r value. we computed both mean interrater and effective reliabilities (see rosenthal, , for conversion statistics). mean interrater reliability estimates agreement between specific pairs o f judges whereas effective reliabilities estimate the reliability o f the mean o f the judges' ratings (rosenthal, ). we, like rosenthal, prefer effective reliabilities because we are more interested in generalizing to how raters in general would agree than in the agreement o f single pairs o f judges evaluating a single face (rosenthal, ). just as a longer test is a more reliable assessment o f a construct than a two-item test, the effective reliability coefficient is a more reliable estimate o f attractiveness because it accounts for the sampling errors in small samples (guilford & fruchter, ; nurmally, ). although we report both estimates o f reliability in table , we discuss the results o f the analysis o f effective reliabilities, and we analyze moderator variables only for effective reliability. for judgment, treatment, and behaviors/traits, studies provided primarily group difference statistics from which effect size could be calculated (t, p, f, and g ). if an effect size was reported only as nonsignificant (without a specific, numerical result reported), it was coded as zero (rosenthal, ). because including such effect sizes may underestimate the actual effect size whereas excluding them may overestimate it, we performed each category and subcategory analysis twice, first including studies in which effect sizes were coded as zero and then excluding these same studies (rosenthal, , ). we calculated the q(b) statistic to assess whether there were any differences between the data sets including or excluding nonsignificant effects coded as zero (see hedges & olkin, ). for each analysis, several statistics are reported (rosenthal, , ): k (number o f effect sizes in the analysis), n (total number o f participants in the analysis), mdn d (median effect size), d+ (averaged weighted effect size), % confidence interval, fail-safe n, and besd (binomial effect-size display). the besd is an estimate o f the practical significance o f the effect size and indicates the change in success rate in the dependent variable due to attractiveness. thus, a besd o f . indicates a % higher success rate for attractive than unattractive people. the absolute success rate for each group is calculated by . + (besd/ ) (rosenthal, ). we report the besd statistic in the form o f the two percentages reflecting, first, the proportion o f attractive children above the mean in the category and, second, the proportion o f unattractive children above the mean (i.e., % vs. % indicates that % o f attractive children are judged more favorably than the average child whereas only % o f unattractive children are judged more favorably than average). finally, we report q (heterogeneity o f the effect sizes). moderator variables following the rationale and procedures o f knight, fabes, and higgins ( ), we assessed variance accounted for by moderator variables using weighted multiple regression analyses that control for relations among moderators. these analyses were performed only for the overall categories because, in most instances, the sample sizes o f the subcategories were too small to allow meaningful subdivision by moderator variables. data reduction and confirmatory analyses including versus excluding studies with unspecified nonsignificant effect size(s) on the basis o f the recommendations o f rosenthal ( ), we performed analyses both including and excluding studies with nonsignificant effect size(s) coded as zero. because the q(b) statistic (hedges & olkin, ) indicated that there were no instances in which significant differences were found between the two data sets, in the interest o f brevity we report t a b l e meta-analyses o f reliability type of % mdn fail-safe type o f judgment estimate r ci r n besd heterogeneity (p) adult within-culture k = ( studies) effective . * . /. . , . , . ( < . ) n = , mean . * . /. . , . . ( < . ) child within-culture k = ( studies) effective . * . l . , . . ( < . , ) n = , mean .' " . /. . , . . ( < . ) adult cross-cultural k = ( studies) effective . * . l . , . , . ( < . ) n = , mean . " . /. . , . . ( < . ) adult cross-ethnic k = ( studies) effective . * . /. . , . . ( < . ) n = mean . * . l . , . . ( < . ) note. k = number o f independent samples; ci = confidence" interval; besd = binomial effect-size display. * p < . . maxims or myths of beauty the analyses excluding nonsignificant effect size(s) coded as zero. (for a list of those studies with nonsignificant effect sizes coded as zero, see appendix j.) fail-safe analyses using the formula from carson, schriesheim, and kinicki ( ), we conducted fail-safe analyses indicating that, on average, over , nonsignificant effect sizes must be added to each of our overall cate- gories to change our results to indicate no differences between attrac- tive and unattractive individuals. thus, the inclusion of unpublished studies we did not locate would have been very unlikely to change the results we report. heterogeneity our analyses revealed heterogeneity, or high variability in effect sizes, for our overall categories and some subcategories. whether heterogeneity of effect sizes is a problem or an asset depends on the goal of the meta-analysis. according to glass ( ) and rosenthal ( ), it is important to understand the nature of "fruit," as well as to examine the nature of "apples and oranges." we expected heterogeneity for our cate- gories because we deliberately conceptualized them as broad constructs, or "fruit," generalizing to broad domains. like other meta-analysts, we there- fore chose to interpret comparisons between categories and subcategories, even if they were heterogeneous (eagly et al., ; feingold, b). to reaff'mn the robustness of the original analysis, we removed outliers to obtain homogeneity (eagly et al., ; hedges & olkin, ; b. t. johnson, ). most effect sizes remained the same or increased. in all cases, the mean ds remained significant. on average, homogeneity was obtained following removal of only % of effect sizes, weft within the guidelines and findings of others (eagly et al., ; hedges & olkin, ). we also found heterogeneity for some categories of moderator variables. we report results for these moderator variables, but we caution the reader to note the heterogeneity statistics presented in the tables. r e s u l t s a n d d i s c u s s i o n overview t h e m e t a - a n a l y s e s s h o w e d that, b o t h w i t h i n a n d across cultures, p e o p l e a g r e e d a b o u t w h o is a n d is n o t attractive. f u r t h e r m o r e , attractiveness is a n a d v a n t a g e i n a variety o f important, real-life situations. w e f o u n d n o t a s i n g l e g e n d e r d i f f e r e n c e a n d surpris- ingly f e w age differences, s u g g e s t i n g t h a t attractiveness is as i m p o r t a n t for m a l e s as for f e m a l e s a n d for c h i l d r e n as for adults. o t h e r m o d e r a t o r v a r i a b l e s h a d little c o n s i s t e n t i m p a c t o n e f f e c t sizes, a l t h o u g h i n s o m e cases there w e r e insufficient data to d r a w conclusions. reliability o f attractiveness ratings within-culture agreement t h e m e t a - a n a l y s i s o f effective reliability coefficients r e v e a l e d t h a t j u d g e s s h o w e d h i g h a n d significant levels o f a g r e e m e n t w h e n e v a l u a t i n g the attractiveness o f others. overall, for adult raters, r = . for ratings o f adults a n d r = . for r a t i n g s o f children, b o t h p s < . (see t a b l e ). m o d e r a t o r v a r i a b l e s w e r e a n a l y z e d i n a s i m u l t a n e o u s w e i g h t e d m u l t i p l e r e g r e s s i o n a n a l y s i s in w h i c h t h e u n s t a n d a r d - i z e d r e g r e s s i o n c o e f f i c i e n t s r e v e a l t h e a s s o c i a t i o n o f e a c h m o d - e r a t o r w i t h t h e o v e r a l l r or d w h i l e c o n t r o l l i n g f o r all t h e o t h e r m o d e r a t o r s ( k n i g h t et al., ). t h e s p e c i f i c d e t a i l s o f t h e m o d e r a t o r a n a l y s e s are r e p o r t e d i n t a b l e . t h e r e w a s a s i n g l e s i g n i f i c a n t m o d e r a t o r e f f e c t ( s a m p l e s i z e f o r a d u l t s ) t h a t d i d n o t a c c o u n t f o r m u c h v a r i a n c e ( . % ) . n o t e t h a t t h e m e a n r e l i a b i l i - t i e s w e r e l o w e r t h a n t h e e f f e c t i v e r e l i a b i l i t i e s ( s e e t a b l e ), b u t t h i s is n o t s u r p r i s i n g g i v e n t h a t m a n y s t u d i e s r e p o r t i n g m e a n r e l i a b i l i t i e s u s e d o n l y t w o raters. cross-ethnic and cross-cultural agreement f o r c r o s s - e t h n i c a g r e e m e n t , the a v e r a g e e f f e c t i v e reliability w a s r = . . cross-cultural a g r e e m e n t w a s e v e n higher, r = . . t h e s e reliabilities for b o t h c r o s s - e t h n i c a n d cross-cultural ratings o f at- tractiveness w e r e significant ( p < . ), i n d i c a t i n g m e a n i n g f u l a n d consistent a g r e e m e n t a m o n g raters (see t a b l e ). o n c e again, n o t h i n g surprising or c o n s i s t e n t e m e r g e d f r o m the m o d e r a t o r anal- yses (see t a b l e ). t h e s e results indicate t h a t b e a u t y is n o t s i m p l y i n the e y e o f the beholder. rather, raters a g r e e d a b o u t t h e attractiveness o f b o t h adults a n d children. o u r f i n d i n g s for reliability o f adult raters w e r e c o n s i s t e n t w i t h f e i n g o l d ( b), w h o m e t a - a n a i y z e d reliability t a b l e moderator variable analyses for effective reliability adult within-culture child within-culture adult cross-cultural adult cross-ethnic predictor unstandardized beta unstandardized beta unstandardized beta unstandardized beta target gender . . - . method of rating - . year of publication . . . ***a . sample size . *b - . . ***b . intercept - . - . - . - . overall r . .t . . qr . . , . "** . qe , . *** . *** . *** . *** note. unstandardized beta weights are entered into the meta-analysis (knight, fabes, & higgins, ); qr = overall regression effect, qe = test of model specification. recent > older studies, b larger > smaller samples. * p < . . * * * p < . . langlois et al. coefficients from samples o f u.s. and canadian adults and ob- tained an average effective reliability o f r = . . m o r e impor- tantly, our cross-cultural and cross-ethnic analyses showed that even diverse groups o f raters readily agreed about who is and is not attractive. both our cross-cultural and cross-ethnic agreement ef- fect sizes are more than double the size necessary to be considered large (cohen, ), suggesting a possibly universal standard by which attractiveness is judged. these analyses seriously question the c o m m o n assumption that attractiveness ratings are culturally unique and merely represent media-induced standards. these find- ings are consistent with the fact that even young infants prefer the same faces as adults (langlois, ritter, roggman, & vaughn, ; langlois et al., ; langlois, roggman, & rieser-danner, ). judgment of attractive and unattractive people both attractive children and adults were evaluated significantly more favorably than unattractive children and adults, even by familiar perceivers (see table ). children the overall d+ ( . ) and the b e s d statistic s h o w e d that a p p r o x i m a t e l y % o f attractive children, c o m p a r e d with o n l y % o f unattractive children, w e r e j u d g e d to b e a b o v e the m e a n for all categories c o m b i n e d . t h e subcategory analyses s h o w e d large e f f e c t sizes, e s p e c i a l l y in the d o m a i n s o f social appeal (d÷ = . ; % vs. %) and a c a d e m i c / d e v e l o p m e n t a l c o m - p e t e n c e (d÷ = . ; % vs. %). a t t r a c t i v e children w e r e also j u d g e d s ignificantly m o r e p o s i t i v e l y on the d i m e n s i o n s o f adjustment (d÷ = . ; % vs. %) and interpersonal c o m - p e t e n c e (d+ = . ; % vs. %). n o v a r i a b l e significantly m o d e r a t e d the findings (see t a b l e ). adults attractive adults were j u d g e d more positively than unattractive adults were (overall d+ = . ; % vs. %), particularly for occupational competence (d÷ = . ; % vs. %). attractive adults were also j u d g e d as having more social appeal (d÷ = . ; % vs. %), as more interpersonally competent (d+ = . ; % vs. %), and as better adjusted (d+ = . ; % vs. %) than unattractive adults. the moderator analyses revealed a single significant influence o f the coded variables on the effect sizes: year o f publication accounted for . % o f the variance. studies published more recently produced larger effect sizes (see table ). w e e x p e c t e d that findings f r o m the attribution literature m i g h t extend to m o r e e c o l o g i c a l l y v a l i d j u d g m e n t s o f attractive and unattractive i n d i v i d u a l s and m i g h t indicate that attractive- ness is m o r e i m p o r t a n t for social j u d g m e n t s than for intellec- t u a l / a c a d e m i c j u d g m e n t s . w e w e r e surprised to find, h o w e v e r , that attractiveness was at least as important for j u d g m e n t s o f a c a d e m i c (children) and o c c u p a t i o n a l (adults) c o m p e t e n c e as it was f o r j u d g m e n t s in social domains, indicating that attractive- ness is an important i n f l u e n c e e v e n in school (see babad, inbar, & rosenthal, ) and the w o r k p l a c e (see h a m e r m e s h & biddle, ). perhaps stranger-attribution research has under- e s t i m a t e d the i m p o r t a n c e o f attractiveness in the e v a l u a t i o n o f intellectual and a c a d e m i c c o m p e t e n c e and success. it m a y b e easier to c o n f o r m to socially desirable m a x i m s in e x p e r i m e n t a l studies o f attributions than to control automatic b e h a v i o r a l biases in the real world. overall, these results indicate that despite c o n v e n t i o n a l teachings, p e o p l e do i n d e e d j u d g e b o o k s b y their c o v e r s e v e n w h e n they h a v e b e h a v i o r a l or other i n f o r m a t i o n on w h i c h to base their j u d g m e n t s . t h e d i f f e r e n c e s in the i n f o r m e d j u d g m e n t about attractive and unattractive children w e r e the strongest e f f e c t sizes w e obtained and, c o m p a r e d with o t h e r e f f e c t sizes in the social sciences, w e r e u n c o m m o n l y large (none b e i n g table meta-analyses of judgment mdn fail-safe heterogeneity judgment k n d d÷ % ci n besd (p) about children ( studies) , . . " . / . , . . ( < . ) academic/developmental . . " . / . . . ( < . ) competence ( studies) adjustment ( studies) , . . * . / . . . ( . ) interpersonal competence , . . * . / . . . (. ) ( studies) social appeal ( studies) , . . " . / . , . . ( < . l) about adults ( studies) , . . * . /. , . . ( < . ) adjustment ( studies) . . * . /. . . (. ) interpersonal competence . . * . /. . . (. ) ( studies) occupational competence . . * . / . . . (. ) ( studies) social appeal ( studies) . . * . /. . . (. ) note. the sum of subcategory studies does not equal the total number of studies in the overall category because some studies contributed dependent variables to more than one subcategory, k = number of independent samples; d+ = averaged weighted effect size; ci = confidence interval; besd = binomial effect-size display. * p < . . maxims or myths of beauty t a b l e moderator variable analyses for differential judgment, treatment, and behavior~traits: children and adults differential judgment differential treatment behavior/trait differences self-perceived traits predictor unstandardized beta unstandardized beta unstandardized beta unstandardized beta children rater type - . target gender . - . . perceiver gender - . type of measure . . - . range of attractiveness -. familiarity - . year of publication - . . - . sample size . . - . age of target . . *a - . age of perceiver -. intercept . - . . overall r . . . qr . . * . qe . ** . . "** adults rater type - . - . - . target gender . . : perceiver gender - . . type of measure - . - . . ***b range of attractiveness - . - . familiarity - . . year of publication . *c . . sample size - . - . . intercept - . - . - . overall r . . . qr . * . . *** qe . . '** , . "** - . - . - . . . . . . " note. unstandardized beta weights are entered into the meta-analysis (knight, fabes, & higgins, ). qr = overall regression effect; qe = test of model specification. a older > younger children, b measures of facial > general attractiveness, c recent > older studies. * p < . . * * p < . . ***p < . . s m a l l e r t h a n d ÷ = . ). a l t h o u g h t h e e f f e c t sizes f o r i n f o r m e d o p i n i o n s a b o u t a d u l t s w e r e n o t as l a r g e as t h o s e f o r c h i l d r e n , t h e y w e r e m e d i u m i n size a n d a m o n g t h e l a r g e r e f f e c t sizes w e o b t a i n e d f o r adults. treatment o f attractive and unattractive people results i n d i c a t e d t h a t attractive c h i l d r e n a n d adults w e r e treated significantly m o r e f a v o r a b l y t h a n unattractive c h i l d r e n a n d adults (see t a b l e ). children f o r c h i l d r e n (overall d ÷ = . ; % vs. %), attractiveness h a d the largest e f f e c t o n e v a l u a t i o n s o f c o m p e t e n c e (d+ = . ; % vs. %), f o l l o w e d b y n e g a t i v e i n t e r a c t i o n (d÷ = - . ; % vs. % ) a n d p o s i t i v e i n t e r a c t i o n (d÷ = . ; % vs. %). a s m a l l e r yet still significant effect o f attractiveness was f o u n d for the s u b c a t e g o r y o f a t t e n t i o n / c a r e g i v i n g (d+ = . ; % vs. %). t a r g e t age, a c c o u n t i n g for . % o f the variance, was a s i g n i f i c a n t m o d e r a t o r variable. studies w i t h older targets p r o d u c e d l a r g e r effect sizes (see t a b l e ). a d u / t s attractive adults were also treated significantly m o r e f a v o r a b l y t h a n unattractive adults w e r e (overall d + = . ; % vs. %). a t t r a c t i v e n e s s h a d the largest effect o n a t t e n t i o n (d+ = . ; % vs. %), f o l l o w e d b y r e w a r d (d+ = . ; % vs. %), p o s i t i v e interaction (d÷ = . ; % vs. %), p o s i t i v e i m p r e s s i o n m a n - a g e m e n t (d÷ = . ; % vs. %), n e g a t i v e i n t e r a c t i o n (d÷ = - . , % vs. %), a n d h e l p - g i v i n g / c o o p e r a t i o n (d+ = . ; % vs. %). n o m o d e r a t o r v a r i a b l e s w e r e s i g n i f i c a n t . ' surprisingly, in addition to b e i n g j u d g e d differently as a func- tion o f t h e i r attractiveness, attractive i n d i v i d u a l s o n a v e r a g e w e r e treated significantly b e t t e r t h a n u n a t t r a c t i v e individuals. t h e s e findings are p o w e r f u l e v i d e n c e that, contrary to p o p u l a r belief, attractiveness effects e x t e n d b e y o n d m e r e " o p i n i o n s " o f others a n d p e r m e a t e actual actions towards others, e v e n t h o u g h p e o p l e m a y not b e aware o f it. the overall effect size for differential treatment was . , including teacher evaluations/grades. without teacher evaluations/grades, d+ = . . no moderator variables were significant when teacher evaluations/grades were excluded from the analysis. langlois et al. t a b l e meta-analyses of treatment mdn fall-safe homogeneity treatment k n d d+ % ci n besd (p) of children ( studies) , . . * . /. , . . (. ) attention and caregiving . . * . /. . . (. ) ( studies) designations of academic , . . " . /. . . (. ) ability ( studies) negative interaction - . - . * - . / - . . . (. ) ( studies) positive interaction . . * . /. . . (. ) ( studies) of adults ( studies) , . . * . /. , . . (. ) attention ( studies) . . " . / . . . (. ) help-giving & cooperation . . * . /. . . (. ) ( studies) negative interaction - . - . * - . / - . . . (. ) ( studies) positive impression . . * . /. . . (. ) management ( studies) positive interaction . . * . /. . . (. ) ( studies) reward ( studies) . . * . /. . . (. ) note. the sum of subcategory studies does not equal the total number of studies in the overall category because some studies contributed dependent variables to more than one subcategory, k = number of independent samples; d+ = averaged weighted effect size; ci = confidence interval; besd = binomial effect-size display. * p < . . do attractive and unattractive individuals behave differently ?--behavior~traits children attractive c h i l d r e n b e h a v e d m o r e positively a n d p o s s e s s e d m o r e positive traits t h a n unattractive c h i l d r e n (overall d + = . ; % vs. %). c o m p a r e d w i t h unattractive children, attractive c h i l d r e n w e r e m o r e p o p u l a r (d+ = . ; % vs. %), b e t t e r adjusted (d÷ = . ; % vs. %), a n d display greater intelligence/perfor- m a n c e c o m p e t e n c e (at÷ = . ; % vs. % ; see t a b l e ). n o m o d e r a t o r variables w e r e significant (see t a b l e ). adults results for adults paralleled those for c h i l d r e n (overall d + = . ; % vs. %). c o m p a r e d w i t h unattractive adults, attractive adults e x p e r i e n c e d m u c h m o r e occupational success (d÷ = . ; % vs. %), w e r e liked m o r e as i n d i c a t e d b y the s u b c a t e g o r y o f popularity (d÷ = . ; % vs. %), and h a d m o r e dating expe- r i e n c e (d÷ = . ; % vs. %), m o r e sexual e x p e r i e n c e ( d ÷ = . ; % vs. %), a n d b e t t e r physical h e a l t h (d÷ = . ; % vs. %). in addition, attractive adults w e r e s o m e w h a t m o r e extra- v e r t e d (d÷ = . ; % vs. %), h a d s o m e w h a t m o r e traditional attitudes (d÷ = . ; % vs. %), w e r e s o m e w h a t h i g h e r in s e l f - c o n f i d e n c e / s e l f - e s t e e m (d÷ = . ; % vs. %), p o s s e s s e d s o m e w h a t b e t t e r social skills (d+ = . ; % vs. %), h a d slightly b e t t e r m e n t a l h e a l t h (d÷ = . ; % vs. %), a n d w e r e v e r y slightly m o r e intelligent (d÷ = . ; % vs. % ; see t a b l e ). o n e m o d e r a t o r a c c o u n t e d for a significant portion o f the vari- a n c e i n the 'overall effect size. t y p e o f attractiveness m e a s u r e a c c o u n t e d for . % o f the variance; studies u s i n g measures o f attractiveness t h a t i n c l u d e d the face plus additional cues h a d h i g h e r effect sizes t h a n studies u s i n g measures o f facial attractive- ness o n l y (see t a b l e ). self-perceptions a t t r a c t i v e adults e x h i b i t e d s o m e w h a t m o r e f a v o r a b l e self- p e r c e p t i o n s t h a n unattractive adults did (overall d ÷ = . ; % vs. %). attractive adults p e r c e i v e d t h e m s e l v e s as m o r e c o m p e t e n t (d+ = . ; % vs. % ) a n d m o r e m e n t a l l y h e a l t h y (d+ = . ; % vs. % ) t h a n unattractive adults (see t a b l e ). n o m o d e r a t o r variable a c c o u n t e d for a significant portion o f the variance. w e were u n a b l e to m e t a - a n a l y z e self-perceptions for children b e c a u s e o n l y one study was r e t r i e v e d (lerner et al., ). l e r n e r et al. ( ) f o u n d a small relation ( r = . ) b e t w e e n self-rated scho- lastic c o m p e t e n c e a n d attractiveness for sixth graders (see t a b l e ). s u m m a r y in conclusion, we f o u n d substantial b e h a v i o r a l a n d trait differ- ences as a f u n c t i o n o f attractiveness. f o r b o t h adults a n d children, g with evaluations of competence included in the analysis, d÷ =. for overall behavioral differences. see note . with evaluations of competence included in the analysis, d+ =. for intelligence/performance competence. see note . maxims or myths of beauty table meta-analyses of behavior~traits mdn % fail-safe homogeneity behavioral differences k n d d+ ci n besd (p) child studies) , adjustment ( studies) , intelligence & performance ( studies) , popularity ( studies) , adult ( studies) , dating experience ( studies) , sexual experience ( studies) , extraversion ( studies) intelligence (t studies) , occupational success ( studies) , mental health ( studies) , physical health ( studies) popularity ( studies) , self-confidence/esteem ( studies) , social skills ( studies) , traditional attitudes ( studies) . . * . /. , . . (. ) . . * . l . . (. ) . . * . /. . . (. ) . . * . /. , . . (. ) . . * . /. , . , . (. ) . . * . /. . . (. ) . . " . /. . . (. ) . . * . /. . . (. ) . . * . /. . . (. ) . . * . /. . . (. ) . . " . /. . . (. ) . . * . /. . . (. ) . . * . l , . t . (. ) . . * . . . . (. ) . . * .t /. . . (. ) . . * . /. . . (. ) note. the sum of subcategory studies does not equal the number of studies in the overall category because some studies contributed dependent variables to more than one subcategory, k = number of independent samples; d+ = averaged weighted effect size; ci = confidence interval; besd = binomial effect-size display. * p < . . attractiveness is strongly related to popularity, and to success for adults. attractiveness is moderately related to both intelligence/ performance and adjustment in children and to both dating and sexual experience in adults. interestingly, for children, our findings for intelligence/performance (d+ = . ) corresponded closely with l. a. jackson et al. ( ), w h o found an effect size o f d = . for children. likewise, our near-zero finding for the relation between intelligence and attractiveness in adults is consistent with feingold ( b). u n l i k e the o v e r a l l results f o r behavior/traits, the e f f e c t sizes f o r s e l f - p e r c e p t i o n s w e r e r e l a t i v e l y small. t h e s i g n i f i c a n t l y s m a l l e r o v e r a l l e f f e c t size f o r s e l f - p e r c e p t i o n s r e l a t i v e to be- havior/traits suggests that u n s t a n d a r d i z e d self-reports are not accurate predictors o f actual b e h a v i o r s and traits o r that self- v i e w s are less susceptible to d i f f e r e n t i a l j u d g m e n t and treat- m e n t than are behaviors. t h e latter interpretation, i f true, sug- gests that social theory m a y b e i n c o r r e c t in its p r e d i c t i o n that d i f f e r e n t i a l treatment, j u d g m e n t , and b e h a v i o r e v e n t u a l l y be- c o m e internalized. a l t e r n a t i v e l y , it m a y b e that the constructs assessed b y current s e l f - p e r c e p t i o n m e a s u r e s are n o t as p s y c h o - m e t r i c a l l y s o u n d as they m i g h t be. additional moderator variables familiarity t o determine whether attractiveness was more important in situations in which participants were less rather than more familiar with each other, w e evaluated the role o f familiarity as a moderator variable o f particular interest. familiarity was coded from ( b r i e f interaction) to (extensive interaction including relationships such as t e a c h e r - c h i l d and parent-child) and entered into the regression analyses for j u d g m e n t and treatment. in no case was familiarity significant, suggesting the surprising conclusion that the effects o f attractiveness are as strong when agents and targets know each other well as when they do not. gender and age effects when controlling for all variables simultaneously, we found not a single significant gender effect. the overall lack o f gender differences in ecologically valid situations suggests that, in most domains, attractiveness is equally important for m e n and women. these findings are consistent with the lack o f gender differences table meta-analyses of adult self-perceptions mdn % fail-safe homogeneity adult self-perceptions k n d d+ ci n besd (p) self-perceived traits ( studies) , . . * . /. . . (. ) competence ( studies) , . . * . /. . . (. ) mental health ( studies) , . . " . /. . . (. ) note. the sum of subcategory studies does not equal the number of studies in the overall category because some studies contributed dependent variables to more than one subcategory, k = number of independent samples; d+ = average weighted effect size; ci = confidence interval; besd = binomial effect-size display. * p < . . langlois et al. found in other meta-analyses of stranger attribution research (eagly et al., ; feingold, b). to evaluate developmental differences in attractiveness effects, we merged the overall category files for adults and children for reliability of attractiveness ratings, judgment, treatment, and be- havior/traits. we then conducted multiple regression analyses as previously described (see table ). no age differences were obtained. because most of the studies available for review in this meta-analysis examined children ages and older, the lack of developmental differences could be explained by the omission of very young children in the reported literature. however, at this point, we conclude that attractiveness is as important, if not more so, for children as for aduks. g e n e r a l d i s c u s s i o n the effects of facial attractiveness are robust and pandemic, extending beyond initial impressions of strangers to actual inter- actions with those whom people know and observe. contrary to conventional wisdom, there is strong agreement both within and across cultures about who is and who is not attractive. further- more, attractiveness is a significant advantage for both children and adults in almost every domain of judgment, treatment, and behavior we examined. the magnitude of attractiveness effects is roughly the same as or larger than that of other important variables in the social sciences (eagly, ). in most cases, the benefits of attractiveness are large enough to be "visible to the naked eye" (cohen, ) and are of considerable practical significance (lip- sey & wilson, ; rosenthal, , ). these meta-analyses starkly illuminate the fundamental contradiction between empiri- cal research and maxims about beauty. on the basis of our results, we conclude that the maxims we examined are myths, not reality: beauty is more than just in the eye of the beholder; people do judge and treat others with w h o m they interact based on attrac- tiveness; and, perhaps most surprisingly, beauty is more than just skin-deep. theoretical mechanisms one of our goals was to illuminate mechanisms explaining how and why attractiveness influences judgment, treatment, and behav- ior. several predictions about how attractiveness functions in these different domains were derived from socialization/social expect- ancy theories and from fitness-related evolutionary theories. socialization and social expectancy theories recall the assumptions underlying socialization and social ex- pectancy theories set forth in the introduction. first, for appearance to have any consistent impact on differential j u d g m e n t or treat- ment, individuals must agree about who is and is not attractive. as we have seen, there is remarkable similarity in attractiveness ratings. indeed, we found substantial agreement about who is and is not attractive both within and across cultures. the finding of high cross-cultural agreement in attractiveness judgments, how- ever, is not consistent with socialization and social expectancy theories because they emphasize cultural differences in percep- tions of attractiveness. second, attractiveness must consistently elicit differential ex- pectations from others. according to the theories, these expecta- tions are acted on b y perceivers in the form of differential judg- ment and treatment toward attractive and unattractive targets. our results extend the findings from the stranger-attribution literature to the informed j u d g m e n t s of others based not on photographs alone but on actual interactions. perceivers judged attractive tar- gets more favorably than unattractive targets even when they knew them. furthermore, these results show that perceivers treated even familiar children and adults differently based on attractiveness (see, e.g., langlois et al., ). attractive and unattractive targets should then develop differ- ential behaviors and traits as a result of differential evaluation and treatment. behavioral and trait differences clearly exist between attractive and unattractive people, supporting this aspect of the table moderator variable analyses for age comparisons differential judgment differential treatment behavior/trait differences predictor unstandardized beta unstandardized beta unstandardized beta rater type -. . -. target gender -. . -. treater gender . physical attractiveness measure . -. -. ***a physical attractiveness range -. familiarity - . - . year of publication . . . age -. . -. sample size . . -. intercept - . - . - . overall r . . . qr . . . "** qe . "** . "** , . "** note. unstandardized beta weights are entered into the meta-analysis (knight, fabes, & higgins, ). qr = overall regression effect; qe = test of model specification. a measures of general > facial attractiveness. ***p < . . maxims or myths of beauty theories. however, we could not examine the presumed causal link between treatment and behavior because only two studies exam- ined the contemporaneous connections between treatment and behavior (s. m. anderson & bem, ; snyder et al., ). furthermore, we found no studies longitudinally investigating the links among judgment, treatment, and behavior to determine an- tecedents and consequents. it is important for future research to take on the task of properly evaluating this perspective. as the last step in the social model, targets should internalize the treatment they receive and develop different self-views. we found only weak support for the assertion that attractive and unattractive adults have different self-views: attractive adults had more posi- tive self-views than unattractive adults did, although the effect sizes are not large. furthermore, we could not evaluate whether differential treatment causes different self-views because of the lack of such studies in the primary literature. although all of these assumptions must be documented for social theory to account for attractiveness effects, certain patterns of age and gender differences would provide additional support for the theory. contrary to the predictions of the theory, however, our results showed that for judgment, treatment, and behavior/traits, attractiveness is just as important for children as for adults and for males as for females. perhaps behavioral differences do increase with age but could not be detected in the research we retrieved, which primarily examined only children ages and older. a similar explanation also may be pertinent for the lack of age differences in judgment and treatment. thus, the lack of research with very young children seriously hampers either a strong en- dorsement or indictment of a social account. socialization and social expectancy theories: evaluation and future directions on the basis of our overall effect sizes for reliability, judgment, treatment, and behavior/traits, we conclude that social theory is a plausible but largely unproven explanation of attractiveness effects (see table ). the theory accurately predicted within-culture agreement in evaluations of attractiveness but missed the mark in asserting the importance of cultural influences for judgments of attractiveness across cultures. we also observed a significant de- ficiency in the extant research evaluating social theory: the lack of research linking expectations to judgments, judgments to treat- ment, and treatment to behavioral outcomes. for the social account to be convincing, the components (judgment, treatment, and be- havior) must be causally related to one another. neither this meta-analysis nor primary research has shown causality; rather, we have shown that attractiveness is correlated independently with each of the components. when enough studies of relations among the components are available, future meta-analysts could model plausible causal pathways (see, e.g., shadish, ). at a mini- mum, however, failure to find correlations among judgment, treat- ment, and behavior as a function of attractiveness could clearly rule out social theory as a plausible explanation. three types of future studies are necessary to establish a causal link among the components of social theory: studies using con- ceptually similar variables, studies that are longitudinal, and stud- ies of very young children. first, studies of judgment, treatment, and behavior must assess variables that bear some conceptual relation to each other for each domain. because the literature is currently fractionated into studies of impressions, studies of judg- ments, studies of treatment, and studies of target behavior, little attempt has been made to define variables conceptually and to measure them simultaneously across the different domains. sec- ond, future research should conduct longitudinal studies to deter- mine which components, if any, are antecedent. attractive and unattractive children may behave differently at birth as a result of biologically based characteristics correlated with attractiveness (see, e.g., field & vega-lahr, ; gangestad, thomhill, & yeo, ; halverson & victor, ; waldrop & halverson, ). perceivers may detect these differences accurately and, as a result, judge and treat attractive and unattractive individuals differently. in contrast, social theory makes a clear, falsifiable prediction about the order of emergence and the causal relations among judgment, treatment, and behavior: differential judgment and treatment cause the development of different behaviors and, thus, must precede the emergence of behavioral differences. longitudinal research would allow a clear demonstration of whether behavioral differences as a function of attractiveness precede, coincide with, or follow differ- ential judgment and treatment. thus, it is essential to conduct research on very young children to disentangle these hypotheses. we retrieved only four studies of behavioral differences as a function of attractiveness in children younger than age . if such research finds that behavioral differences precede differential judgment and treatment, social theory could be eliminated as the sole theoretical account of attractiveness effects, although certainly subsequent differential judgment and treatment could augment the display of different behaviors and traits. another deficiency we observed is the divorce between social theory and the data concerning gender differences. we did not find the expected gender differences in the importance of attractive- ness, although perhaps we could not detect them because much extant research examined only a single gender or did not distin- guish between males and females in the data analysis. future research must report differences in the effects of attractiveness for males and females separately before social theory can be conclu- sively evaluated. fitness-related evolutionary theories fitness-related evolutionary theories (good genes, human mate selection, differential parental solicitude) all agree that because morphological characteristics such as facial attractiveness are hon- est indicators of fitness, health, quality, and reproductive value, attractiveness should be important in human interactions (barber, ; buss & schmitt, ; daly & wilson, ; symons, ; thornhill & gangestad, ). all three models agree that perceivers should consistently detect and recognize attractiveness, both within and across cultures, because humans have evolved universal standards of facial attractiveness based on clues to health and reproductive fitness. furthermore, as an evolved trait, agree- ment about attractiveness should be evident within as well as between cultures. as we have shown with reliability, this criterion has been met, and all three fitness-related theories have proven to be more predictively accurate than social theory in this regard. mate selection. mate-selection theory makes clear predictions about the importance of attractiveness. the theory focuses many of its predictions on gender differences in the importance of attrac- tiveness because the theory is concerned primarily with the devel- table correspondence between hypotheses and results langlois et al. hypothesis prediction social theory . within-culture agreement (high reliability) . between-culture agreement (low reliability) . agreement higher for female than male faces . agreement higher for older than younger judges . differential judgment . differential treatment . differential behavior . differential self-views . attractiveness more important for females than males . differential judgment and treatment important during childhood . behavioral differences cumulate and increase over time . behavior caused by judgment and treatment mate-selection theory . within-culture agreement (reliability) about attractiveness . between-culture agreement (reliability) about attractiveness . agreement higher for female than male faces . agreement higher for older than younger judges . differential judgment . differential treatment . differential behavior . attractiveness more important for females than males . adult-centered theory: attractiveness either not important for children or ignored for children . judgment and treatment caused by target behavior good-genes theory . within-culture agreement . between-culture agreement . similar (high) level of agreement for male and female faces . similar (high) level of agreement for older and younger judges . differential judgment . differential treatment . differential behavior . attractiveness more strongly related to status and fitness than to other types of characteristics . attractiveness equally important for both sexes . behavioral differences evident early . judgment and treatment caused by target behavior differential parental solicitude theory . within-culture agreement . between-culture agreement . similar (high) level of agreement for male and female faces . differential judgment . differential treatment . differential behavior . attractiveness equally important for both sexes . behavioral differences evident early . judgment and treatment caused by target behavior supported not supported not supported not supported supported supported supported partially supported not supported supported insufficient primary research to evaluate insufficient primary research to evaluate supported supported not supported not supported supported supported supported not supported not supported insufficient primary research to evaluate supported supported supported supported supported supported supported not supported supported partially supported: behavior differences present during childhood insufficient primary research to evaluate supported supported supported supported supported supported supported partially supported: behavior differences present during childhood insufficient primary research to evaluate opment o f traits desired by each gender. the theory predicts that higher reliability should be obtained for female rather than male attractiveness because attractiveness is especially important as an indicator o f reproductive fitness in w o m e n (l. a. jackson, ). however, this is not what the data show. instead, w e found a surprising lack o f gender differences in the four different meta- analyses o f the reliability o f attractiveness judgments. second, because m e n prefer and seek attractive women, by extension, m e n should also j u d g e and treat them more positively (g. f. miller, ). w o m e n should favor m e n with resources more than they favor attractive men. thus, attractiveness should be more important in h o w men j u d g e and treat w o m e n than in how w o m e n j u d g e and treat m e n (buss & barnes, ; buss & schmitt, ; l. a. jackson, ). our findings did not support these predictions for either j u d g m e n t or treatment. w e found no gender differences in the importance o f attractiveness, contrary to the predictions o f mate-selection theory but consistent with the findings o f eagly et al. ( ) in their meta-analysis o f the stranger-attribution literature. w e note, however, that for treat- ment, there were few studies in which m e n and w o m e n were directly compared or in which same-sex treatment was examined. thus, this hypothesis has not yet received sufficient attention from primary research. most o f the extant primary research that supports mate-selection theory is almost entirely based on paper-and-pencil maxims or myths of beauty questionnaires o f preferences--behavioral research must be con- ducted before the importance of gender differences can be either substantiated or refuted. in contrast to the gender difference predictions for reliability, judgment, and treatment, mate-selection theory predicts an ab- sence of gender differences in behavior/traits. rather, it predicts that initially unrelated traits coevolve because o f assortative mat- ing (buss, ). our results show that attractiveness was gener- ally related to status variables: attractive individuals were more successful, had better social skills, and were more mentally healthy. furthermore, we did not find any significant gender differences, consistent with the prediction. finally, mate-seleedon models ignore children, but we found large effects of attractiveness on the judgment, treatment, and behavior of children. either some other mechanism must account for these findings or the theory needs revision to include an account o f how and why it is relevant to children. good genes. good-genes theory predicts differential judgment and treatment as a function of attractiveness, either as a response to preexisting differential behaviors and traits o f attractive and unattractive people or because humans have evolved to prefer attractive people for their good health. in either case, humans should judge and treat attractive people more favorably than un- attractive people. our overall findings support this prediction. furthermore, because attractiveness accurately advertises health, quality, and heterozygosity, attractiveness should be more strongly associated with some target behaviors and traits than others. for example, attractiveness should signal health, intelli- gence, and other measures of competence, but it should not be correlated with characteristics such as traditional attitudes because such characteristics have no obvious link to survival. for adults, there is mixed support for this prediction. because they were fairly large, the effect sizes for subcategories of behavior/traits such as occupational success, physical health, popularity, dating experi- ence, and sexual experience support the prediction. however, the relatively small effect sizes for mental health and social skills provide little support for the theory. furthermore, attractiveness was as highly related to traditional attitudes as to many of the indexes of status, undermining the discriminative utility of the theory. behavioral differences as a function of attractiveness should also be expressed very early in life because good health presum- ably is as important for young children as for adults. for children, attractiveness is strongly associated with popularity and moder- ately associated with intelligence and adjustment, consistent with good-genes theory. the age at which behavioral differences as a function of attractiveness become evident, however, is not clear because most of the extant research fails to investigate attractive- ness effects in very young children. finally, because good health is critical to survival, attractiveness should be equally relevant and important to both genders (thies- sen, ; thornhill & gangestad, ). consistent with this prediction, we found no gender differences in the importance of attractiveness for either adults or children. differential parental solicitude. differential parental solici- tude theory claims that, to enhance their own reproductive success, parents invest differently in children depending on each child's fitness, quality, and reproductive potential (daly, ; daly & wilson, , ). by extension, if attractiveness is an indicator of quality, parents and other adults should invest more in attractive than unattractive children (barden et al., ; buss, ; field & vega-lahr, ; langlois et al., ). thus, attractiveness should be very important for children, perhaps more important for children than for adults. our highly significant effect sizes for children generally support this prediction. finally, because the theory assumes that attractiveness is an equally valid indicator of health and quality in boys and girls, no gender differences would be expected in how boys and girls are judged and treated as a function o f attractiveness (daly & wilson, ). this prediction is consistent with the lack o f gender differ- ences we obtained. fitness-related evolutionary theories: evaluation and future directions table summarizes how well the aggregated data fit with predictions made by the various evolutionary perspectives. not surprisingly, no single evolutionary theory provides a complete account of the obtained attractiveness effects. rather, depending on the domain and situation, a combination of all three theories can provide a plausible explanation of our findings. good-genes theory predicts and can reasonably explain our finding that attractiveness is equally important for males and females. the theory also pre- dicts, and we found, health differences between attractive and unattractive targets. differential parental solicitude theory predicts and can account for our finding that attractiveness is o f consider- able importance for children. likewise, mate-selection theory is partially supported, although some important predictions about gender differences are not supported and the theory ignores chil- dren. thus, although evolutionary mechanisms may have the po- tential to satisfactorily explain attractiveness effects, an important step for evolutionary theory is the creation and empirical testing of a model that more clearly specifies the exact situations and devel- opmental trajectories of these various mechanisms. for example, is mate selection a modular mechanism that operates only when human beings are consciously seeking a mate, or is it a more general, constantly functioning mechanism that colors all human interactions? does mate selection work in conjunction or compe- tition with differential parental solicitude or good genes? these are only a few of the questions that remain to be addressed and empirically tested before a comprehensive and precise theory of evolution-driven attractiveness effects can be derived. mathemat- ical modeling specifically designed to assess the simultaneous impact of different evolutionary mechanisms (see, e.g., kirk- patrick, ) may help answer these questions. as mentioned earlier, these fitness-related evolutionary theories were not specifically designed to address the impact o f attractive- ness, except perhaps for mate-selection theory. because our meta- analytic findings show that these theories are plausible explana- tions of attractiveness effects, it is time for a more constrained theory specific to attractiveness effects to be developed. our findings suggest that a hybrid evolutionary account can plausibly explain a number of attractiveness effects. however, as with social theory, important pieces are missing from this hybrid evolutionary account. because evolutionary theory specifies a causal relation between behavior, judgment, and treatment, the same deficiency in the research base that we noted above also applies here. similarly, research investigating attractiveness effects in very young children langlois et al. is required. finally, although our meta-analysis revealed a link between health and physical attractiveness, this finding was based on relatively few effect sizes and some questionable measures of health (e.g., blood pressure, which c o u l d be a result of unattrac- tiveness because, as we have seen, unattractive people are j u d g e d and treated differently than attractive people). additional research in this area is especially warranted given the central importance of health in fitness-related evolutionary theories. l i m i i a t i o n s the strengths and weaknesses of these conclusions reflect the strength and weaknesses of the research we reviewed and of meta-analytic techniques in general (h. cooper & hedges, ; matt & cook, ). much of the extant research on attractiveness is atheoretical and not conceptually driven. we hope that this review will stimulate primary research to evaluate theoretical mechanisms underlying attractiveness effects. the analyses of moderator variables were often uninformative because of insufficiencies in the research. they revealed the need for research with children younger than years of age, for research with adults older than college age, for research that evaluates male and female perceivers separately, and for research investigating children's informed judgments of adults following actual interac- tions. thus, we caution the reader to reserve j u d g m e n t about the importance of these moderator variables until more research is available. like the stranger-attribution research reviewed by eagly et al. ( ), most of the research we reviewed categorized people into two levels of attractiveness, high or low. even after reviewing over effect sizes, we can conclude only that attractive and unat- tractive individuals are different in how they are judged, how they are treated, and how they behave. because we do not know whether either group is significantly different from individuals of m e d i u m attractiveness, we cannot determine whether the differ- ences between attractive and unattractive individuals occur be- cause attractiveness is an advantage, because unattractiveness is a disadvantage, or both. future research should not limit itself to investigating only two levels of attractiveness. w e did, however, compare studies investigating the effects of attractiveness when only dichotomous groups were selected (attractive vs. unattractive) and studies investigating the effects of attractiveness when the full. range of attractiveness was represented. in no case was this vari- able significant, suggesting that attractiveness effects are not lim- ited to only the extreme ends of the distribution. we acknowledge that not all social or evolutionary theorists would agree with the details of all of our hypotheses. the evolu- tionary psychology of attractiveness is particularly complicated. for example, m a n y predictions of mate-selection theory are rela- tive. attractiveness is more important for m e n than women when choosing a mate; attractiveness is also more important for choos- ing long-term mates than short-term mates. if attractiveness is somewhat important for w o m e n choosing long-term mates, would this finding falsify the theory? the answer is unclear. we hope that any disagreements o f interpretation will lead to future efforts to bring theoretical clarity and specificity to the field. finally, no one theory is likely to be a single and unique explanation of attractiveness effects; rather, the theories should be viewed as complementary rather than competitive in explaining attractiveness effects. even if all predictions of social theory are strongly supported by future primary research, the theory still begs the question of why and how stereotypes based on attractiveness originated in the ftrst place. perhaps most of the proximal effects of attractiveness are due to social expectancies and socialization, b u t the distal roots and origins of stereotypes about attractive a n d unattractive people are due to the evolutionary past. perhaps the three maxims about beauty originated to compensate for underly- ing and largely unacknowledged and unconscious human disposi- tions to use facial appearance as an important cue for social interaction. after all, if humans were not biased to judge others on their appearance, they would not need to remind their children not to judge books by their covers. if people did not assume that beauty was an index of behaviors and traits, they would not need to be reminded that beauty is only skin-deep. however, despite their prevalence and history, these maxims apparently have not been successful in counteracting the effects of attractiveness on people's judgments, treatments, and, ultimately, behavior. a n alternative viewpoint concludes the opposite about the max- ims. perhaps they have been too successful. perhaps, because children and adults have listened carefully to and assimilated these maxims, they are confident that they have unique standards of beauty, that they do not judge or treat people differently based on their appearance, and that beauty has nothing to do with a person's behaviors and traits. if people believe that they behave in accord with these principles of decency, they have no reason to recognize or change their behavior. thus, the very research that identifies the powerful way in which people react to physical attractiveness might ameliorate these apparent unconscious and automatic pro- cesses. being cognitive, humans have the behavioral plasticity and foresightedness to learn to oppose these influences, and the max- ims can again remind people to behave more consciously and humanely. lo in many studies, level of attractiveness (high vs. low) was defined by a median split, thereby including individuals of medium attractiveness. although our results do not allow us to determine if attractiveness is an advantage or unattractiveness a disadvantage, they do generalize to the entire population. r e f e r e n c e s references marked with an asterisk indicate studies included in the meta-analyses. *abbott, a. r., & sebastian, r. j. 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( ). what sounds beautiful is good: the vocal attractiveness stereotype. journal of nonverbal behavior, , - . maxims or myths of beauty appendix a studies included in meta-analyses of cross-cultural and cross-ethnic rdiability type of number of target mean effective study reliability raters gender reliability reliability bernstein, lin, & mcclellan ( ), study bemstein, lin, & mcclellan ( ), study n. cavior & howard ( ) cunningham, barbee, & pike ( ), study cunningham, barbee, & pike ( ), study cunningham, roberts, barbee, druen, & wu ( ) cunningham, roberts, barbee, druen, & wu ( ) d. jones & hill ( ) d. jones & hill ( ) madden & houingworth ( ) martin ( ) martin ( ) martin ( ) mcarthur & berry ( ), study mcarthur & berry ( ), study thakerar & iwawaki ( ) udry ( ) zebrowitz, montepare, & lee ( ) zebmwitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) zebrowitz, montepare, & lee ( ) cc b . . ce b . . ce m . . ce m . . ce m . . cc f . . ce f . . cc f . . cc m . . cc b . . ce f . . cc f . . cc f . . cc b . . cc m . . cc m . . cc , f . . ce b . . cc b . . cc b . . ce b . . cc b . . cc b . . ce b . . cc b . . cc b . . note. studies included in the meta-analyses of within-culture reliability are noted in the references. cc = cross-cultural; ce = cross-ethnic; m = male; f = female; b = both. (appendixes continue) langlois el" al. a p p e n d i x b s t u d i e s i n c l u d e d i n t h e m e t a - a n a l y s i s a s s e s s i n g w i t h i n - c u l t u r e r e l i a b i l i t y abbot & sebastian ( ) babad, irrbar, & rosenthal ( ) bangh & parry ( ) berscheid, dion, walster, & walster ( ) t. a. brown, cash, & noles ( ) bums & farina ( ) campbell, kleim, & olson ( ) cash & begley ( ) cash & bums ( ) cash & smith ( ) n. cavior & dokecki ( ) n. cavior & howard ( ) chaiken ( ) cheek & buss ( ) clifford ( ) p. s. cooper ( ) critelli & waid ( .) curran ( ) outran & lippold ( ) depanlo, tang, & stone ( ) dickey-bryant, lautenschlager, mendoza, & abrahams ( ) diener, wolsic, & fujita ( ) dion & berscheid ( ) elder, van nguyen, & caspi ( ) farina et al. ( ) felson & bohrnstedt ( ) friedman, riggio, & casella ( ) gabriel, critelli, & ee ( ) gallucci & meyer ( ) gangestad & thornhill ( ) garcia, stinson, ickes, bisonette, & briggs ( ) gifford, ng, & wilkinson ( ) goldberg, gottesdiener, & abramson ( ) goldman & lewis ( ) greenwald ( ) hadjistavropoutos, tuokko, & beattie ( ) hanseu, sparacino, & ronchi ( ) hildebrandt & carman ( ) houingworth ( ) d. j. jackson & huston ( ) r. w. johnson, doiron, brooks, & dickinson ( ) kaats & davis ( ) kahn, hottes, & davis ( ) kalick, zebrowitz, langlois, & johnson ( ) kenealy, frude, & shaw ( ) kowner & ogawa ( ) langlois, ritter, roggman, & vaughn ( ) langlois et al ( ) langlois, roggman, & rieser-danner ( ) larranee & zuckerman ( ) leinbach & fagot ( ) mandel & shranger ( ) markley, kramer, parry, & ryabik ( ) martindale, ross, hines, & abrams ( ) mathes & kahn ( ) mcgovem, neale, & kendler ( ) l. c. miller & cox ( ) moisan-thomas, conger, zeuinger, & firth ( ) napoleon, chassin, & young ( ) noles, cash, & winstead ( ) o'grady ( ) reis, nezlek, & wheeler ( ) reis, wheeler, nezlek, kemis, & spiegel ( ) rieser-danner, roggman, & langlois ( ) rowe, clapp, & wallis ( ) salvia, algozzine, & sbeare ( ) samuels & ewy ( ) sarason, samson, hacker, & basham ( ) shackelford & larsen ( ) j. shea, crossman, & adams ( ) g. j. smith ( ) j. smith & krantz ( ) snyder, berscheid, & glick ( ) sparacino ( ) sparacino & hansell ( ) steffen & redden ( ) stewart ( ) stewart ( ) sussman & mueser ( ) turner, gilliland, & klein ( ) vaughn & langiois ( ) walster, aronson, abrahams, & rottmann ( ) wessberg, marriotto, conger, farrell, & conger ( ) zakahi & duran ( ) maxims or myths of beauty appendix c studies included in meta-analysis of judgment of attractive and unattractive adults physical sample target perceiver rater attractiveness study size gender gender familiarity type measure physical attractiveness range r. d. brown ( ) m m n g r. d. brown ( ) f m n g t. a. brown, cash, & noles (t ) m m i g t. a. brown, cash, & noles ( ) f m i g byme, ervin, & lamberth ( ) m f i g byme, ervin, & lamberth ( ) f m i g campbell, kleim, & olson ( ) f b i g chaiken ( ) m m i f chenflnik ( ) b . b n g chemlnik ( ) b b n g cherulnik ( ) b b n g diener, wolsic, & fujita ( ) b b i f dipboye, fromkin, & wiback ( ) t m f i f farina et al. ( ), study f m i f foster, pearson, & imahori ( ) m m n g friedman, riggio, & casella ( ) m m i g friedman, riggio, & casella ( ) f m i g gifford, ng, & wilkinson ( ) m m i g goldman & lewis ( ) m m n g goldman & lewis ( ) f m n g hamish, abbey, & debono ( ) m m n g w. h. jones, freemon, & goswick ( ), study m m i g w. h. jones, freemon, & goswick ( ), study f m i g kleck & rubenstein ( ) f m n g kuhlenschmidt & conger ( ) f m i g marlowe, schneider, & nelson ( ) t b b i f nelson, hayes, felton, & jarrett ( ) m m n g neumann, critelli, & tang ( ) m f i f shapiro, struening, shapiro, & batten ( ) m m n g steffen & redden ( ) m f n g c . c . c . c . c . c . c . d . d . d - . d . c . d . c . c . c . c . c . c . c . c . c . c . d . c . d . c . c . c . c . note. m = male; f = female; b = both; = less; = more; na = not provided in primary article but either or ; i = independent; n = nonindependent; f = facial measure; g = global measure; c = continuous; d = dichotomous. appendix d studies included in meta-analysis of judgment of attractive and unattractive children physical sample target perceiver rater perceiver attractiveness study size gender gender type age measure familiarity d dion & berscheid ( ) b b i c felson & bohrnstedt ( ) f b i c felson & bohrnstedt ( ) m b i c kenealy, frude, & shaw ( ) f b i a kenealy, fmde, & shaw ( ) m b i a lippitt ( ) b f n a lippitt ( ) b f n a lippitt ( ) b f n a rieser-danner, roggmarm, & langlois ( ) b f t a weisfeld, block, & ivers ( ) m f n c weisfeld, weisfeid, & callaghan ( ) m b n c weisfeld, weisfeld, & callaghan ( ) f b n c weisfeld, weisfeld, & callaghan ( ) f b n c f . f . f . f . f . g - . g - . g . f - . g . g - . g . g . note. m = male; f = female; b = both; i = independent; n = nonindependent; tess; = more. a = adult; c = child; f = facial measure; g = global measure; = (appendixes continue) langlois et al. a p p e n d i x e s t u d i e s i n c l u d e d i n m e t a - a n a l y s i s o f t r e a t m e n t o f a t t r a c t i v e a n d u n a t t r a c t i v e a d u l t s physical physical sample target agent rater attractiveness attractiveness study size gender gender type measure range familiarity d alaln ( ) b b i f alcock, solano, & kayson ( ) b b i g s. m. anderson & bern ( ) b m i f s. m. anderson & bern ( ) b f i f benson, karabenick, & lemer ( ) b b i f brundage, derlega, & cash ( ) m f i f byrne, ervin, & lamberth ( ) m f n g byrne, erviu, & lamberth ( ) f m n g h. e. cavior, hayes, & cavior ( ) f b i f chalken ( ) b b i f depaulo, tang, & stone ( ) b b i f efran & patterson ( ) nr b i f farina et al. ( ), study f b i f kleck & rubenstein ( ) f m i g langlois et al. ( ), study f b i f langlois et al. ( ), study f b i f langlois, ritter, roggman, & vaughan ( )~ study ' b b i f langlois, ritter, roggman, & vaughan ( ), study f b i f langlois, roggman, & rieser-danner ( ), study f b i f mathes & edwards ( ), study b b n g minas, hartnett, & nay ( ) f b n g nadler ( ) f f i f pellegrini, hicks, meyers-winton, & antal ( ) b b n g poweu & dabbs ( ), study b b nr f raza & carpenter ( ) b b n g romer & berkson ( ) b b n g samuels & ewy ( ) b b i f samuels & ewy ( ) b b i f j. a. shea & adams ( ) m f n f j. a. shea & adams ( ) f m n f siater et al. ( ) f b i f sroufe, chaikin, cook, & freeman ( ), study f b i f sroufe, chaikin, cook, & freeman ( ), study f b i f stewart ( ) b nr i g stewart ( ) b nr i g stokes & bickman ( ) f f i g west & brown ( ), study f m nr g wilson ( ) f m nr f wilson ( ) f m nr f d . d . d . d . d . d i . c . c . c . d . d . d . c . d . d . d . d . d . c . d . d . d . d . c . c . d . d . c . c . d . d . d . c . c . d . d . d . d . d . note. m = male; f = female; b = both; i = independent; n = nonindependent; f = facial measure; g = global measure; c = continuous; d = dichotomous; = less; = more. m a x i m s o r m y t h s o f b e a u t y appendix f studies included in meta-analysis of treatment of attractive and unattractive children physical sample target perceiver target attractiveness study size gender gender age familiarity measure physical attractiveness range barocas & black ( ) m f n r barocas & black ( ) f f n r berkowitz & frodi ( ), study f f berkowitz & frodi ( ), study m f dalley, allen, chinsky, & veit ( ) b b . dion ( ), study m f dion ( ), study f f dion ( ) b b nr elder, v a n nguyen, & caspi ( ) f m n r felson & bohrnstedt ( )/felson ( ) m n r n r felson & bohrnstedt ( )/felson ( ) f n r n r hildebrandt & carman ( ) b b n r karraker ( ) b f . kcnealy, frude, & shaw ( ) m b n r kenealy, frude, & shaw ( ) f b n r langlois, ritter, casey, & sawin ( ) b f langlois, ritter, r o g g m a n , & v a u g h n ( ), study b b . leinbach & fagot ( ) m b . leinbach & fagot ( ) f b . l e m e r , delaney, hess, jovanovic, & v o n eye ( ) b f . l e m e r & l e m e r ( ) b f . salvia, algozzine, & sheare ( ) b b n r g. j. smith ( ) f b . v a u g h n & langlois ( ) m b n r v a u g h n & langlois ( ) f b n r z a h r ( ) b n r n r f c . f c . g d . g d . f c . g d . g d - . f d . g c . f c . f c . f c - . f c - . f c . f c . f c . f d . f c o. f c . f c . f c . f c . g d . f c . f c . f c . note. m = male; f = female; b = both; = less; = more; f = facial measure; g = global measure; c = continuous; d = dichotomous. (appendixes continue) langlois et al. a p p e n d i x g s t u d i e s i n c l u d e d i n m e t a - a n a l y s i s o f a d u l t b e h a v i o r / t r a i t d i f f e r e n c e s study sample size gender rater type attractiveness measure d barocas & vance ( ) barocas & vance ( ) barocas & vance ( ) barocas & vance ( ) baugh & parry ( ) berscheid, dion, walster, & walster ( ), study berscheid, dion, walster, & walster ( ), study brislin & lewis ( ) brislin & lewis ( ) r. d. brown ( ) r. d. brown ( ) brunswick ( ) bums & farina ( ) campbell, klein, & olson ( ) campbell, klein, & olson ( ) cash & begley ( ) cash & begley ( ) cash & smith ( ) cash & smith ( ) cash & soloway ( ) cash & soloway ( ) chaiken ( ) critelli & waid ( ) critelli & waid ( ) curran ( ) curran ( ) curran & lippold ( ), study curran & lippold ( ), study curran & lippold ( ), study curran & lippold ( ), study curran, neff, & lippold ( ) curran, neff, & lippold ( ) depaulo, tang, & stone ( ) dickey-bryant, lautenschlager, mendoza, & abrahams ( ) farina et al. ( ), study farina et al. ( ), study feingold ( , ) feingold ( , ) friedman, riggio, & casella ( ) gabriel, critelli, & ee ( ) gabriel, criteui, & ee (i ) gauuci & meyer ( ) gangestad & thornhill ( ) gangestad & thornhill ( ) garcia, stinson, ickes, bisonette, & briggs ( ) garcia, stinson, ickes, bisonette, & briggs ( ) glasgow & arkowitz ( ) glasgow & arkowitz ( ) greenwald ( ) greenwald ( ) hamermesh & biddle ( ) hamermesh & biddle ( ) hamermesh & biddle ( ) hamermesh & biddle ( ) hanseu, sparacino, & ronchi ( ), study hanseu, sparacino, & ronchi ( ), study hansell, sparacino, & ronchi ( ), study d. j. jackson & huston ( ), study d. j. jackson & huston ( ), study r. w. johnson, doiron, brooks, & dickinson ( ) r. w. johnson, doiron, brooks, & dickinson ( ) w. h. jones, briggs, & smith ( ) w. h. jones, briggs, & smith ( ) kaats & davis ( ) kalick, zebrowitz, langlois, & johnson ( ) m n g . m n g . f n g . f n g . f i g . m i g . f i g . m i g . f i g . m n g . f n g . m i g . f i g . m n g . f n g . m n g . f n g . m n g . f n g . m n g . f n g - . b i g . m i g . f i g . m i g - . f i g . m i g . f i g . m i g . f i g . m i g . f i g . b i f . m i f . f i f . f i f . m i f - . f i f - . b i g . m i f . f i f - . f i f . f i f . m i f . m i g - . f i g . m n g . f n g . m i g . f i g . m i g . m i g . f i g . f i g . b i f . f i f . f i f . f n g . f n g . f i f . f i f . b i g - . b i g . f i g . m i f . maxims or myths of beauty a p p e n d i x g (continued) study sample size gender rater type attractiveness measure d kalick, zebrowitz, langlois, & johnson ( ) f i kleck & rubenstein ( ) m i kowner ( ) b n kowner & ogawa ( ) m i kowner & ogawa ( ) f i kuhlenschmidt & conger ( ) f i larrance & zuckerman ( ) b i longo ( ) b i mandel & shrauger ( ) m n martindale, ross, hines, & abrams ( ) b i martindale, ross, hines, & abrams ( ) b i mathes & kahn ( ) m i mathes & kahn ( ) f i mcgovem, neale, & kendler ( ) , f i l. c. miller & cox ( ) f i mohr ( ) m i mohr ( ) f i molar & l u n d ( ) m i mohr & l u n d ( ) f i moisan-thomas, conger, zellinger, & firth ( ) m i murphy, nelson, & cheap ( ) b i napoleon, chassin, & young ( ) b i noles, cash, & winstead ( ) b i o'grady ( ) m i o'grady ( ) f i pellegrini, hicks, meyers-winton, & antal ( ) b n pilkonis ( ) b i raskin & terry ( ), study b n raza & carpenter ( ) b n reis, nezlek, & wheeler ( ) m i reis, nezlek, & wheeler ( ) f i reis et al. ( ) m i reis et al. ( )/reis, wheeler, nezlek, kernis, & spiegel ( ) f i romer & berkson ( ) b n roszell, kennedy, & grabb ( ) , b n rowe, clapp, & wallis ( ) m i rowe, clapp, & wallis ( ) f i sarason, sarason, hacker, & basham ( ) b i shackelford & larsen ( ) m i shackelford & larsen ( ) f i shapiro, struening, shapiro, & barten ( ) b n shapiro, struening, shapiro, & barten ( ) b n singer ( ) f i singer ( ) f i singer ( ) f i snyder, berscheid, & glick ( ) m i sparacino ( ) m i sparacino & hansell ( ), study m i sparacino & hansell ( ), study f i sparacino & hansell ( ), study m i sparacino & hansell ( ), study f i sparacino & hansell ( ), study m i sparacino & hansell ( ), study f i steffen & redden ( ) m n stelzer, desmond, & price ( ) f i stewart ( ) b i stewart ( ) b i snssman et al. ( ) b i sussman & mueser ( ) f i turner, gilliland, & klein ( ) b i turner, gilliland, & klein ( ) b n walster, aronson, abrahams, & rottmann ( ) m i walster, aronson, abrahams, & rottmann ( ) f i wessberg, marriotto, conger, farrell, & conger ( ) m i zakahi & duran ( ) m i zakahi & duran ( ) f i zebrowitz, collins, & dutta ( ) f i f . f . g . f . f - . g - . f . g - . g . f . f . g - . g . f - . f . g . g . g . g . g . f . f . g - . f - . f . g - . g . f - . g . g . g . g . g - . g . f . f . f . f . f . f . g . g . f . f . f . g . f - . f . f . f - . f - . f . f - . g . g . g . g . g . g . g . g . g . g . g . f . f . g . note. m = male; f = female; b = both; i = independent; n = nonindependent; f = facial measure; g = global measure. (appendixes continue) langlois et al. appendix h studies included in meta-analysis of child behavior/trait differences study sample size gender age rater type atlxactiveness measure d l. k. anderson ( ) b . i babad, inbar, & rosenthal ( ) b n n. cavior & dokecki ( ) m . i n. cavior & dokecki ( ) m . i n. cavior & dokecki ( ) f . i n. cavior & dokecki ( ) f . i n. cavior & howard ( ), study m i n. cavior & howard ( ), study m i n. cavior, miller, & cohen ( ) m . n n. cavior, miller, & cohen ( ) f . n clark & ayers ( ) b . n cole ( ) m . i cole ( ) f . i cole, martin, & powers ( ) b . n p. s. cooper ( ) b . i dailey, allen, chinsky, & veit ( ) b . n dion & berscheid ( ) m i dion & berscheid ( ) f i felson ( ), study m . i felson ( ), study f . i felson ( ), study , m . n fridell, zucker, bradley, & maing ( ) f . i hollingworth ( ) b . i hughes, howell, & hall ( ) m . i hughes, howell, & hall ( ) f . i jovanovic, lemer, & lemer ( ) b . i kenealy, gleeson, frude, & shaw ( ) b . i kleck, richardson, & ronald ( ), study m . i krantz, friedberg, & andrews ( ) b . i leinbach & fagot ( ) m . i leinbach & fagot ( ) f . i lemer, delaney, hess, jovanovic, & yon eye ( ) b . i lerner & lemer ( ) b . i lemer et al. ( ) b . i lippitt ( ) b . n lippitt ( ) b . n lippitt ( ) b n moran & mccullers ( ) b . i murphy, nelson, & cheap ( ) b . i salvia, algozzine, & sheare ( ) b . i serketich & dumas ( ) b nr i j. smith & krantz ( ) m . i j. smith & krantz ( ) f . i sparacino & hansell ( ), study m . i sparacino & hansell ( ), study f . i sparacino & hansell ( ), study f . i vanghn & langlois ( ) m i vaughn & langlois ( ) f i weisfeld, weisfeld, & callaghan ( ) m . n weisfeld, weisfeld, & callaghan ( ) m . n weisfeld, weisfeld, & callaghan ( ) m . n weisfeld, weisfeld, & callaghan ( ) f . n weisfeld, weisfeld, & callaghan ( ) f . n weisfeld, weisfeld, & callaghan ( ) f n weisfeld, weisfeld, & callaghan ( ) f n zucker, wild, bradley, & lowry ( ) m . i f . g . g . g . g . g . f . f . g . g . g . g . g . g . f . f . f . f - . g . g . g . f . f . g . g~ . g . f . f . f . f . f . f . f . f . g . g . g . f - . f . f . g . f . f . f . f - . f - . f . f . g . g . g . g . g . g . g . f . n o t e . m = male; f = female; b = both; i = independent; n = nonindependent; f = facial measure; g = global measure. maxims or myths of beauty appendix i studies included in meta-analysis of self-perceived traits in attractive and unattractive adults physical physical sample target perceiver rater attractiveness attractiveness study size gender gender type measure range d abbott & sebastian ( ) f f i berscheid, dion, walster, & walster ( ), study m m i berscheid, dion, walster, & walster ( ), study m m i berscheid, dion, walster, & walster ( ), study f f i bums & farina ( ) f f i campbell, kleim, & olson ( ) f f i cash & bums ( ) m m i cash & burns ( ) f f i chaiken ( ) m m i farina et al. ( ), study f f i farina et al. ( ), study f f i gabriel, critelli, & ee ( ) m m i gabriel, critelli, & f_,e ( ) f f i gifford, ng, & wilkinson ( ) m m i d. j. jackson & huston ( ), study f f i kaats & davis ( ) f f i o'grady ( ) m m i reis, nezlek, & wheeler ( ) m m i reis, nezlek, & wheeler ( ) f f i reis et al. ( ) m m i reis et al. ( ) f f i sarason, sarason, hacker, & basham ( ) m m i umberson & hughes ( ) , m m n f c . g c . g d . g d . g c . g c . g c . g c - . f d . f c . f c . f c - . f c - . g c . g d . g c . g c . g c . g c . g c . g c . f c . g c . note. m = male; f = female; b = both; i = independent; n = nonindependent; f = facial measure; g = global measure; c = continuous; d = dichotomous. a p p e n d i x j s t u d i e s i n c l u d e d i n t h e m e t a - a n a l y s e s b u t n o t e l s e w h e r e r e p o r t e d b e c a u s e n o n s i g n i f i c a n t r e s u l t s w e r e c o d e d a s e q u a l t o z e r o bull, jenkins, & stevens ( ) cheek & buss ( ) clifford ( ) dion & stein ( ) fugita, agle, newman, & walfish ( ) goldberg, gottesdiener, & abramson ( ) hadjistavropolous, tuokko, & beattie ( ) w. h. jones, freemon, & goswick ( ) kahn, hottes, & davis ( ) kanekar & ahluwalia ( ) leinbach & fagot ( ) markley, kramer, parry, & ryabik ( ) pittenger & baskett ( ) salvia, sheare, & algozzine ( ) j. a. shea & adams ( ) wessberg, marriotto, conger, farrell, & conger ( ) williams & ciminero ( ) wilson & donnerstein ( ) r e c e i v e d a u g u s t , r e v i s i o n r e c e i v e d o c t o b e r , a c c e p t e d o c t o b e r , • small is beautiful: models of small neuronal networks coneur- ; no. of pages small is beautiful: models of small neuronal networks damon g lamb and ronald l calabrese available online at www.sciencedirect.com modeling has contributed a great deal to our understanding of how individual neurons and neuronal networks function. in this review, we focus on models of the small neuronal networks of invertebrates, especially rhythmically active cpg networks. models have elucidated many aspects of these networks, from identifying key interacting membrane properties to pointing out gaps in our understanding, for example missing neurons. even the complex cpgs of vertebrates, such as those that underlie respiration, have been reduced to small network models to great effect. modeling of these networks spans from simplified models, which are amenable to mathematical analyses, to very complicated biophysical models. some researchers have now adopted a population approach, where they generate and analyze many related models that differ in a few to several judiciously chosen free parameters; often these parameters show variability across animals and thus justify the approach. models of small neuronal networks will continue to expand and refine our understanding of how neuronal networks in all animals program motor output, process sensory information and learn. address emory university, department of biology, clifton rd, atlanta, ga , united states corresponding author: calabrese, ronald l (ronald.calabrese@emory.edu, rcalabre@biology.emory.edu) current opinion in neurobiology , : – this review comes from a themed issue on microcircuits edited by edward callaway and eve marder - /$ – see front matter published by elsevier ltd. doi . /j.conb. . . introduction models of the small neuronal networks of invertebrates, especially rhythmically active central pattern generators (cpg), have proven to be fruitful subjects of investi- gation, revealing general principals of neuronal network function and generating hypotheses later supported by the living systems they represent. over the past two decades, models of ‘simple’ networks, powered by effi- cient desktop computing and a wealth of physiological data, have provided guiding insights into how neuronal networks function. over the past decade, theoretical studies, but now supported by experimental analysis in please cite this article in press as: lamb dg, calabrese rl. small is beautiful: models of smal www.sciencedirect.com several different networks and species, have shown that reliable network output can result from networks in which parameters (e.g. the intrinsic membrane proper- ties (maximal conductances) of the neurons and the strengths of the synaptic connections) show – -fold animal-to-animal variability [ – ]. consequently, to understand a neuronal network through biophysical modeling, we must construct populations of models with multiple sets of parameter values corresponding to parameters from different individuals [ – ]. a sobering consequence is that the computational effort needed to produce a state of the art biophysical model is vastly increased. the situation is clearly still fluid [ , ], but the reaction in the modeling community has ranged from a continued pursuance ‘ideal parameter sets’ or sticking to averaged values for parameters to what prinz [ ], calls ensemble modeling, where multiple functional instances are identified and examined. in this review we sample the diversity of small network modeling approaches to highlight how each continues to contribute significant new insights. a note on models and parameters before we continue, we should distinguish between models and parameters. the models discussed in this review consist of differential equations that describe the dynamics of state variables, for example, membrane potential (vm) and the gating variables of voltage de- pendent conductances. embedded in these equations are a number of parameters, including maximal con- ductances as well as half activation voltages and time constants of channel gates. some of these parameters are considered free, or variable between instances, while the remaining parameters are fixed. for example, in the pioneering work of prinz et al. [ , ], only maximal conductances were considered free parameters. even with powerful computing resources, it is not possible or desirable to consider all instances of a model. making a model then involves deciding on a neuronal structure (single or multiple compartments), network connec- tivity, descriptive equations (often derivatives of the hodgkin–huxley formalism), which parameters are free and the range over which each may vary. these decisions will all be driven by the data available and by the investigators’ intuition for which parameters are likely to be significant in controlling neuronal activity. in short, the ability to consider multiple instances of a model does not free one from making a good model, and making a good model requires detailed knowledge of the system and judgment about what details can be ignored and which parameters fixed. l neuronal networks, curr opin neurobiol ( ), doi: . /j.conb. . . current opinion in neurobiology , : – http://dx.doi.org/ . /j.conb. . . mailto:ronald.calabrese@emory.edu mailto:ronald.calabrese@emory.edu http://dx.doi.org/ . /j.conb. . . http://www.sciencedirect.com/science/journal/ microcircuits coneur- ; no. of pages swimming in tritonia the swimming cpg of tritonia has long been the object of experimental analyses and modeling [ , ]. calin-jage- man et al. [ ��], updated the getting model [ ] to reflect new data on synaptic connectivity, intrinsic properties and intrinsic neuromodulation with a careful refitting of intrinsic and synaptic parameters, only to find that the network model did not produce the swim motor pattern in either the unmodulated or modulated state. unde- terred, they first compared their model’s parameters to those of the original model and adjusted those that significantly differed to the values of the original model. this process restored the ability of the model to produce the swim pattern. they also performed a brute force parameter space investigation of the differing parameters and identified all models that produced the swim pattern ( %). they showed that all parameters sets leading to proper network function were contiguous in parameter space. then, using discriminant analysis and dimensional stacking, they identified key parameters contributing to proper network function. somewhat at a loss to explain how their carefully fitted model failed while the getting model was successful, they suggest that, ‘even if it reflects a nonphysiological configuration, it has still been a useful sign-post toward understanding the conditions that could enable the swim-motor program.’ feeding in lymnea the feeding cpg of lymnea is well characterized [ ] and has been analyzed for mechanisms of associative learning in the form of single-trial, food-reward classical condition- ing [ , ]. vavoulis et al. [ ], developed a model of the core cpg with fixed parameters selected to match excit- ability criteria and other physiological data. this model captured feeding activity and predicted physiological phenomena that were later verified experimentally. cor- responding work in the aplysia feeding cpg [ ] failed to capture feeding activity without an additional putative neuron which has yet to be identified physiologically. an interesting aspect of the aplysia study is the extensive sensitivity analysis, including perturbations during simu- lations, which demonstrated the model activity’s robust- ness to parameter variation. vavoulis et al. [ �], have continued the lymnea work by focusing on the mechanisms of persistent depolarization of the cerebral giant cells (cgcs) that underlies single- trial, food-reward classical conditioning. to construct the model cgc neuron they used a combination of fitting to available voltage-clamp data and parameter optimization techniques for determining maximal conductances and dynamic parameters. remarkably, optimization led to tight ranges for most parameters, though some time constant parameters were not tightly constrained. a model based on median parameter values captured cgc depolarization without altered excitability, please cite this article in press as: lamb dg, calabrese rl. small is beautiful: models of smal current opinion in neurobiology , : – observed in the living system, and identified two critical maximal conductances in this process; simultaneous increases in maxgnap, a persistent sodium current, and maxgd, a delayed rectifier. heartbeat in hirudo the heartbeat cpg of hirudo has been analyzed [ ] and modeled, for example [ ], extensively. weaver et al. [ ], presented a model of the entire core cpg that shows the utility of systematic parameter variation of a small subset of parameters in network analysis. two bilateral pairs of premotor interneurons, phased differently with respect to the timing kernel of the cpg, show a phase progression on one side and near synchrony on the other. these phase differences are achieved by blending inhibitory synaptic input and electrical coupling. making simplifying assumptions based on symmetry in the network, these investigators probed a range of maximal conductances for the inhibitory synapse and the electrical coupling to each premotor interneuron. the analysis established parameter values that produced model activity within the range observed in a large number of preparations. the relative parameter values predicted by this model were confirmed physiologically in voltage-clamp exper- iments [ ] (see figure ). the control of motor neurons by this cpg has also been extensively analyzed and modeled [ , , � ]. garcia et al. [ ] used averaged data to define input phasing and synaptic strength profiles and a simplified single compartment model for the motor neurons. that model failed to achieve quantitatively accurate average output phasing [ , ]. an analysis of preparations for the timing of the activity of the four premotor interneurons of the cpg (input phasing) and of their strength of inhibi- tory output (synaptic strength profiles) onto motor neurons, and the timing (output phasing) of the motor neurons revealed wide animal-to-animal variability in synaptic strengths and input and output phasing [ ]. wright and calabrese [ � ], used input phasing, synaptic strength profiles and phasing targets from individual animals as inputs to the garcia model [ ], but were still not able to achieve greater accuracy. those results, as well as dynamic clamp experiments also using individualized synaptic input patterns, indicated the involvement of motor neuron intrinsic properties not encompassed by the motor neuron model, thus leading to the conclusion that a multi-compartmental motor neuron model with more sophisticated intrinsic properties was required [ , � ]. respiration in vertebrates the respiratory cpg of vertebrates has been studied in detail at many levels. it is a complex system consisting of millions of neurons with a great diversity of intrinsic and synaptic properties [ ]. moreover, the cpg is influ- enced by myriad extrinsic inputs, primarily related to l neuronal networks, curr opin neurobiol ( ), doi: . /j.conb. . . www.sciencedirect.com http://dx.doi.org/ . /j.conb. . . small is beautiful lamb and calabrese coneur- ; no. of pages please cite this article in press as: lamb dg, calabrese rl. small is beautiful: models of small neuronal networks, curr opin neurobiol ( ), doi: . /j.conb. . . figure hn , , , , , , hn silent s hn(p, ) hn(p, ) hn(p, ) hn(p, ) hn(s, ) hn(s, ) hn(s, ) hn(s, ) hn(s, ) hn(s, ) hn(s, ) hn(r, ) hn(s, ) hn(p, ) hn(p, ) hn(p, ) hn(p, ) peristaltic synchronous s mv hn(r, ) synchronoushn(l, ) peristaltic hn(r, ) synchronoushn(l, ) peristaltic ipsilateral electrical coupling ip si la te ra l i n h ib ito ry s yn a p tic s tr e n g th g s yn s (n s ) g s yn s (n s ) gcoup (ns)gcoup (ns) expt. range only expt. avg. ± . *sd both constraints met (a) (b) (c) (d) hn(s, ) current opinion in neurobiology (a) bilateral activity (recorded extracellularly) in the premotor heart interneurons (hn( ), hn( ), hn( ) and hn( ) interneurons) of the core heartbeat cpg showing these neurons in peristaltic (p) and synchronous (s) coordination modes. the middle spike of the peristaltic hn( ) interneuron is used as a reference to compute phase: vertical dashed lines ease comparison of relative (unilateral) phase in the two coordination modes. the bilateral record is artificially reconstructed from a unilateral recording that switched between coordination modes and aligned so that peristaltic and synchronous hn( ) interneurons fire out of phase ( . ). (b) circuit diagram showing synaptic connections among interneurons of the core heartbeat cpg. small colored/ black circles indicate inhibitory chemical synapses, and diodes indicate rectifying electrical junctions. for simplicity, in the cpg diagram, cells with similar input and output connections and function are combined. only one hn( ) interneuron is rhythmically active at a time, and it determines synchronous coordination ipsilaterally and peristaltic coordination contralaterally. (c) covarying maximal conductances for the inhibitory synapse and the electrical coupling to identify appropriate values (colored asterisks and arrows). for every combination of maximal conductances, phase and duty cycle for that middle premotor interneuron were calculated and compared with those of individual neuron’s experimentally recorded values (see graph legend). (d) core cpg model activity (bilateral) with parameters selected in (c). after weaver et al. [ ]. www.sciencedirect.com current opinion in neurobiology , : – http://dx.doi.org/ . /j.conb. . . microcircuits coneur- ; no. of pages relevant respiratory signals such as pco . a large-scale computational model of the respiratory cpg [ ] suc- cessfully reproduced data from arterially perfused brainstem-spinal cord rat preparations in which tran- sections sequentially removed rostral components of the respiratory network. that model was based on populations of hodgkin–huxley style neurons in the bötzinger complex (bötc), pre-bötzinger complex (pre-bötc), and ventral respiratory group, with excit- atory drive from the pons and retrotrapezoid nucleus (rtn). building on this work, rubin et al. [ ��, ], reduced the complexity and employed the small network approach used for invertebrate models. the authors used activity- based, non-spiking, single neuron models to represent populations of spiking neurons, allowing for the appli- cation of bifurcation analysis. the reduced model repro- duced the three major dynamic regimes observed in previous experimental studies and large-scale models [ , ], supporting the idea that the proposed architec- ture and drive structure are reasonable. similar to exper- imental studies using brain stem transections, the removal of pontine drive converted the initial three-phase oscillations characteristic of in vivo respiration to two- phase oscillations, which lack the post-inspiratory phase, characteristic of en bloc preparations that retain rostral nuclei. subsequent removal of inhibition from bötc expiratory neurons associated with removal of tonic drive from rtn converted the two-phase oscillations to one- phase inspiratory oscillations characteristic of slice prep- arations of the pre-bötc. two oscillatory mechanisms appear to underlie these oscillatory patterns at the cellular level, in particular in the pre-bötc complex: a persistent sodium-driven oscil- lation and a calcium-driven oscillation. two recent papers [ , � ] present models which include both nap and ca driven oscillatory behavior, although the specifics of the models presented differ. an important aspect of the toporikova and butera model [ � ] is that several import- ant responses to neuromodulator, pharmacological, and environmental influences are replicated, despite its rela- tively simple construction. food processing in crustaceans the food processing cpgs in the stomatogastric nervous system (stn) of decapod crustaceans continue to be a focus of modeling studies with wide implications for how neuronal networks achieve functional output. early last decade, researchers began to use the stg system to address questions of model degeneracy, where the same functional output resulted from models with widely dif- fering underlying parameters. this raised the question of how reliable network activity as well as sensitivity to neuromodulation and perturbation could be achieved in these small neural networks. please cite this article in press as: lamb dg, calabrese rl. small is beautiful: models of smal current opinion in neurobiology , : – recent investigation by grashow et al. [ ], used a sim- plified neuronal model to approach the broad question of how underlying neural parameters contribute to overall network performance. the authors coupled a morris lecar model neuron with a pharmacologically isolated living stg neuron via dynamic clamp, and then varied the maximal conductance of the artificial synapses and a model ih current injected into the stg neuron. echoing prinz [ ], the results showed that diverse parameter values can lead to similar network output. in other cases, however, the same parameter values can also result in wildly different network output, showing that differences between the intrinsic properties of the biological neurons can drastically alter the resulting pattern in the hybrid network. thus, network activity is more resilient to variations in some regions of parameter space than others, strongly supporting earlier modeling work [ ]. nadim et al. [ �], also used a simplified model to inves- tigate how a specific synapse influences network activity. their stripped down model of a primary stn pacemaker network, composed of the anterior burster (ab) and pyloric dilator (pd) neurons, allowed them to apply phase plane analysis to investigate the role of the only known chemical synapse onto this network, the lateral pyloric (lp) to pd synapse. in the living system, the removal of this synapse has no effect under control conditions, although it was proposed that the lp-pd synapse would stabilize the ab/pd cycle period [ , ]. nadim et al. [ � ], verified this experimentally, and then used their model to help explain how. essentially, the synapse reinforces the stability of the pacemaker by overriding the influence of perturbations — either slowing down incipient advances or speeding up incipient delays. moving from highly reduced to more complicated models, taylor et al. [ ��], uses what is variously referred to as ensemble [ ], family [ ], or population modeling. in this approach, many similar models are considered and each instance, or individual, is a different combination of free parameter values. they constructed a biophysical baseline model, tuned to a subset of experimental data, and then explored the parameter space around this model. by randomly sampling the parameter space and then simulating and perturbing each instance, they could identify models which were acceptable across all of several metrics. those acceptable models had widely differing parameters, but did not have the strong corre- lations between these parameters that were expected based on experimental correlations between channel mrna [ – ]. conclusions each of these models has advantages and limitations, but all contribute to our understanding of neuronal net- works — from circuit-specific findings, such as putative new members, to broad conclusions about the likely l neuronal networks, curr opin neurobiol ( ), doi: . /j.conb. . . www.sciencedirect.com http://dx.doi.org/ . /j.conb. . . small is beautiful lamb and calabrese coneur- ; no. of pages structure and regulation of network topology and cellular properties. we were only able to present a selection of small network models, leaving out many other fascinating systems which are actively modeled, especially neuronal circuits underlying locomotion [ – , � , � ]. the abil- ity of small network models to facilitate a mechanistic understanding of such a broad array of complex systems speaks to their heuristic power. as we move forward, models of small networks will no doubt clarify many interesting issues. for example, although some studies find that variability of intrinsic properties at the cellular level becomes less important at the network level [ ], others suggested that network topology and neural dynamics strongly interact and both are of critical importance [ ]. furthermore, we know that neuromodulation plays a key role in pattern generation in many systems, yet much of the research on the small neural networks which underlie behavior appears to touch only superficially on the nd messenger systems involved. the levels of regulation available to neurons are myriad: epigenetics, transcription and translation regulatory mechanisms, splice variation, interrupted or delayed translation, and post-translational modification. the next logical step is to extend our investigations into the nd messenger pathways which drive observable change in electrophysiological properties. not only will a more complete understanding of the cellular pathways which influence electrophysiological activity help us understand the unperturbed state of small neural networks, but also the effects of and interactions between neuromodulators and extrinsic perturbations. in addition to expanding the complexity of our models to include more cellular com- plexity, the ensemble modeling approach is likely to expand as we move forward, especially given the ever- increasing computational capabilities available. models of small networks are beautiful windows into how neuronal networks in all animals function, and we look forward to exciting new models that will continue to expand and challenge our understanding of them. acknowledgements funding: ns to rlc. angela wenning and eleanore d. sternberg for proofreading. references and recommended reading papers of particular interest, published within the period of review, have been highlighted as: � of special interest �� of outstanding interest . goldman ms, golowasch j, marder e, abbott lf: global structure, robustness, and modulation of neuronal models. j neurosci , : - 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. . � borisyuk r, al azad ak, conte d, roberts a, soffe sr: modeling the connectome of a simple spinal cord. front neuroinformatics , : . using a wealth of physiological and anatomical data and probabilistic developmental rules, the authors make a model, based on axonal growth and connection, of the connectome of spinal cord neurons involved in swimming in hatchling xenopus tadpoles. the end result is about neurons of six different cell-types with a total of about connec- tions. each repetition of the modeling process results in a different connectome instantiation, each conforming to experimentally determined distributions of cell bodies, dendrites, and axon lengths. the model, because it can generate multiple instantiations, provides an ideal match to the ensemble modeling approach and shows a way forward for modeling the complex neuronal networks of vertebrates. . � roberts a, li wc, soffe sr: how neurons generate behavior in a hatchling amphibian tadpole: an outline. front behav neurosci , : . the authors summarize an extensive body of behavioral, physiological, and anatomical data on the behavioral repertoire and its neuronal bases of hatchling xenopus tadpoles. models (consisting of only cell types) of the neuronal networks underlying swimming and struggling behaviors are presented and mechanistically compared. combining such models with the connectome model of borisyuk et al. ( ) in the future promises significant new insights into complex spinal neuronal net- works. . gaiteri c, rubin je: the interaction of intrinsic dynamics and network topology in determining network burst synchrony. front comput neurosci , : . l neuronal networks, curr opin neurobiol ( ), doi: . /j.conb. . . www.sciencedirect.com http://dx.doi.org/ . /j.conb. . . small is beautiful: models of small neuronal networks introduction a note on models and parameters swimming in tritonia feeding in lymnea heartbeat in hirudo respiration in vertebrates food processing in crustaceans conclusions acknowledgements references and recommended reading .pdf hal id: halshs- https://halshs.archives-ouvertes.fr/halshs- submitted on jan hal is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. the documents may come from teaching and research institutions in france or abroad, or from public or private research centers. l’archive ouverte pluridisciplinaire hal, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. sophisticated bidders in beauty-contest auctons stefano galavotti, luigi moretti, paola valbonesi to cite this version: stefano galavotti, luigi moretti, paola valbonesi. sophisticated bidders in beauty-contest auctons. . �halshs- � https://halshs.archives-ouvertes.fr/halshs- https://hal.archives-ouvertes.fr documents de travail du centre d’economie de la sorbonne sophisticated bidders in beauty-contest auctions stefano galavotti, luigi moretti, paola valbonesi . maison des sciences Économiques, - boulevard de l'hôpital, paris cedex http://centredeconomiesorbonne.univ-paris .fr/ issn : - x sophisticated bidders in beauty-contest auctions∗ stefano galavotti† luigi moretti‡ paola valbonesi§ abstract we study bidding behavior by firms in beauty-contest auctions, i.e. auctions in which the winning bid is the one which gets closest to some function (average) of all submitted bids. using a dataset on public procurement beauty-contest auctions, we show that firms’ observed bidding behavior departs from equilibrium and can be predicted by a sophistication index, which captures the firms’ accumulated capacity of bidding close to optimality in the past. we show that our empirical evidence is consistent with a cognitive hierarchy model of bidders’ behavior. we also investigate whether and how firms learn to bid strategically through experience. jel classification: c ; d ; d ; d ; h . keywords: cognitive hierarchy; auctions; beauty-contest; public procurement. ∗ we are indebted to francesco decarolis for providing us with his codes. we would like to thank for their valuable comments: malin arve, riccardo camboni, ottorino chillemi, decio coviello, klenio barbosa, gordon klein, luciano greco, marco pagnozzi, tim salmon, giancarlo spagnolo, alessandra bianchi and participants at the “workshop on economics of public procurement” (stockholm, june ), international conference on “contracts, procurement, and public-private arrangements” (chaire eppp iae panthéon-sorbonne, florence, june ), th annual conference of the italian economic association (bologna, october ), “workshop on how do governance complexity and financial constraints affect public-private contracts? theory and empirical evidence” (padova, april ), earie conference (milan, august ), seminar at pse & u. paris i panthéon-sorbonne (february ), st berkeley- paris organizational economics workshop (april ), seminar at the department of economics, leicester university (october ). †corresponding author. department of economics and management, university of padova, via del santo , padova, italy. phone: + . fax: + . email: ste- fano.galavotti@unipd.it. ‡centre d’economie de la sorbonne, université paris panthéon-sorbonne, - bvd de l’hôpital, paris, france. email: luigi.moretti@univ-paris .fr. §department of economics and management, university of padova, via del santo , padova, italy; higher school of economics, national research university, moscow-perm, russia. email: paola.valbonesi@unipd.it. documents de travail du centre d'economie de la sorbonne - . introduction the competition among firms in market economies generates winners and losers: some firms survive, grow up and pay dividends to their shareholders, others have poor performances or go bankrupt and exit the market. why does this happen? is it because, though all firms are making their optimal decisions, the winners have some structural or informational advantage over the losers? or is it simply because the losers are making the wrong decisions, or, in game-theoretic language, they are not playing their equilibrium strategies? answering to this question is typically difficult, as we rarely observe all the fine details of the game that firms are actually playing. moreover, even though we can replicate market games in controlled lab-experiment, it is questionable whether and to what extent these insights can be generalized to real-world situations where stakes are large. in this paper to address the above question using field data from a peculiar procurement auction market: average bid auctions. these auctions resemble beauty-contest games in that the winning bid is the one which gets closest to some function (average) of all submitted bids. average bid auctions have very precise nash equilibrium predictions which are essentially unaffected by variables that are often unobservable: in equilibrium, either all or – possibly – most bids should be equal. this makes it an ideal setting to investigate possible deviations from equilibrium. using an original dataset of procurement average bid auctions in the italian region of valle d’aosta, we observe that actual bids significantly depart from equilibrium, being characterized by a systematic heterogeneity. starting from the consideration that the peculiar rules of these auctions call for refined strategic thinking by bidders, as a bidder has to anticipate the behavior of all other bidders (whereas in a first-price auction, it is sufficient to guess the distribution of the highest competing bid), we hypothesize that the observed heterogeneity could be the result of the interaction of firms with different abilities in performing an iterated process of strategic reasoning, in the spirit of the cognitive hierarchy (ch, henceforth) model by camerer et al. ( ). applied to our context, this model predicts that more sophisticated firms, being able to formulate more accurate beliefs about how others are going to bid, make “better” bids, i.e. closer to the truly optimal one. we estimate an empirical reduced form model which shows that, in accordance with the main prediction of the ch model, the firm’s sophistication index, measured by the accumulated capacity of bidding well in the past, is strongly and positively correlated to the goodness of that firm’s bid, measured by the (negative of the) distance from the truly optimal bid. this result is robust to several specifications of the empirical model; most importantly, it is also confirmed when we focus our analysis on a sample of auctions awarded with a new average bid format, which includes a stochastic component. interestingly, our evidence shows that a significant learning process is at work: firms become better strategic bidders as they participate in more and more auctions of the same format; instead, sophistication acquired in one format does not significantly affects performance in the other. this paper mainly contributes to two strands of literature. first, we relate to two recent papers which fit structural econometric ch model on real data. in particular, goldfarb and yang ( ) study the decision by internet service providers whether or not to adopt the then new k modem technology in . goldfarb and xiao ( ) investigate the choice by u.s. managers of competitive local exchange carriers (clecs) to enter local telephone markets after the telecommunication act in . both papers uncover significant heterogeneity of documents de travail du centre d'economie de la sorbonne - . sophistication among managers, with more sophisticated managers less likely to adopt the new technology or to enter markets with more competitors. they also show that the level of sophistication is higher for firms operating in larger cities, with more competitors or in markets with more educated populations (goldfarb and yang) and for more experienced, better educated managers (goldfarb and xiao). both these papers assume a ch model, but do not address whether their model fits better than an equilibrium model. in our paper, instead, we do not assume any structural model but show that the capacity of firms of making better decisions has a systematic component which goes in a direction coherent with a ch model. second, our paper contributes to a recent empirical and experimental literature on average bid auctions. decarolis ( ) and bucciol et al. ( ) empirically compare the performances of average bid and first-price auctions for the procurement of public works in italy. these papers show that the first-price is in general associated with lower awarding prices but worse performances in terms of cost and time overruns in the completion time. conley and decarolis ( ) argue that the average bid auction is weak to collusion as the members of a cartel, by placing coordinated bids, may pilot the average, thus increasing the probability that one of them wins. using a dataset (different from ours) of italian average bid procurement auctions, they find that a large fraction of auctions (no less than %) is likely to be affected by the presence of cartels; thus, they conclude that the observed deviations from nash equilibrium are mostly due to a cooperative behavior by bidders. our paper suggests a complementary explanation to the observed bidding behavior in this type of auctions, but based on a non- cooperative argument. nevertheless, we provide and discuss some arguments supporting the robustness of our findings to the possible presence of collusion. chang et al. ( ) experimentally investigate whether a simple average bid auction can be an effective alternative to first-price auctions for an auctioneer concerned with reducing winner’s curse phenomena in common value settings. their results suggest a positive answer: prices are higher in the average bid than in the first-price auction, thus reducing losses and virtually eliminating default problems. interestingly, in the average bid auction, subjects do not coordinate on high prices as the nash equilibrium would predict; rather, they follow a bidding strategy which is strictly increasing in their cost signal. the authors argue that a level-k model would qualitatively generate bidding functions with this shape, but would predict larger bids than observed. they propose an almost-equilibrium explanation to their evidence: while subjects with intermediate signals do best-respond to the behavior of the others, subjects with extreme signals misinterpret the informative content of their signal and bid suboptimally. the rest of the paper is organized as follows: in section , we illustrate the auction formats considered, describe our dataset and present some preliminary descriptive evidence; in section , we show that our evidence is clearly inconsistent with nash equilibrium and obtain a testable prediction from a ch model; this prediction leads to the empirical analysis, provided in section ; section offers a discussion of our results, with further supporting evidence and robustness checks; section briefly concludes. brown et al. ( ) use a ch model to explain empirical evidence on box-office premiums associated to cold-opened movies, i.e. movies that are not shown to critics prior to their release. in their paper, consumers, not firms, have limited capacity of strategic thinking and firms exploit the consumers’ näıveté to extract more surplus by not disclosing information on the low quality movies. documents de travail du centre d'economie de la sorbonne - . auction formats and descriptive evidence since , the large majority of public works in italy are procured by means of average bid auctions: these are auctions in which the winner is not the firm that offers the best (i.e. lowest) price, but the one whose offer is closest to some endogenous function (average) of all submitted offers. participating firms submit a (sealed) price consisting of a percentage discount on the reserve price set by the contracting authority (ca). once the ca has verified the firms’ legal, fiscal, economic, financial and technical requirements, the winning firm is determined according to the following mechanism (see figure , top panel): discounts are ordered from the lowest to the highest and a first average (a ) is computed by averaging all bids except the % highest and lowest bids. then, a second average (a ) is computed by averaging all bids strictly above a (again disregarding the % highest bids). the winning bid is the one immediately below a . in the event that all bids are equal, the winner is chosen randomly. we call this auction format “average bid”, or simply ab. figure – ab (top panel) and abl (bottom panel) auction. our dataset collects auctions for public works issued by the regional government of valle d’aosta in the period - (data are from moretti and valbonesi, ). it contains all bids submitted in each auction, together with several detailed information at the firm- and auction-level: for each participating firm, we know the identity (i.e. company name) and some characteristics such as size, location, number of pending public procurement projects, and subcontracting position (mandatory or optional, see moretti and valbonesi, , for a discussion on this); for each auction, we have information on the reserve price, the task of the hence, a higher discount means a lower price paid by the ca. in the rest of the paper, we will use the terms bids and discounts interchangeably. for example, if there are bids, the lowest and the highest bids are not considered in the computation of a . when this % is not an integer, the number of neglected bids is obtained by rounding up: for example, if there are bids, the lowest and the highest bids are not considered. the ab format has been compulsory in italy until june for all contracts with a reserve price below mln euro. the ratio behind the choice of the ab format instead of the first-price was the consideration that the former, by softening price competition, would have generated higher awarding prices, thereby reducing the likelihood that, when the ex-post cost of realizing the project turns out to be larger than expected, the winning firm declares bankruptcy or asks for a renegotiation of the contract (for more on the trade-off between price and performance in first-price and average bid auctions, see, among others, cameron, , albano et al., , bucciol et al., , decarolis, ). after , every ca has been allowed to choose between ab and first-price auction (but since october , first-price auctions are compulsory for contracts above mln euro). documents de travail du centre d'economie de la sorbonne - . tendered project and the estimated duration of the work. an interesting feature of our dataset is that it covers a change in the auction format. in fact, while public works before were awarded through the ab format described before, since , and only in valle d’aosta, a new average bid awarding mechanism has been intro- duced. the new format differs from the previous one as it includes a stochastic component; for this reason, we call it “average bid with lottery” auction, or simply abl. the abl auction works as follows (see figure , bottom panel): given the average a computed as in ab, a random number (ω) is extracted from the set of nine equidistant numbers between the lowest bid above the first decile of bids and the bid immediately below a . averaging ω with a , the winning threshold w is obtained and the winning bid is the one closest from above to w , provided this bid does not exceed a . otherwise, the winner will be the bid equal or closest from below to w . again, if all bids are identical, the winner is chosen randomly. to be precise, if we denote by d % the discount immediately above the first decile of the bid distribution and by da the discount immediately below a , then the winning threshold is w = [a + ω]/ where ω = d % + (da − d %)ν/ and ν can be any integer between and . hence, the winning threshold will necessarily fall within an interval whose lower and upper bounds are [a + d % + (da − d %)/ ]/ and [a + d % + (da − d %) / ]/ , respectively. for reasons that will be clear later on in the paper, we denote the lower bound of this interval by a . figure shows non-parametric kernel density estimation of the bid distributions in the ab and abl formats (dashed line for ab and straight line for abl). for each auction, discounts have been re-scaled using a min-max normalization (the lowest discount in an auction takes value , while the highest takes value ). figure – discounts in ab and abl: kernel density estimation. figure highlights two relevant features. first, in either formats, bids are clearly neither uniformly, nor normally distributed. second, the distributions are clearly asymmetric and different across the two formats: in ab, most bids are concentrated in the right end of the support of the distribution of bids; in abl, most bids are concentrated below the midpoint of the support. documents de travail du centre d'economie de la sorbonne - . theory: equilibrium vs. cognitive hierarchy the descriptive evidence presented in figure suggests that the bidding behavior by firms in our dataset is characterized by some regularities. in this section, we first investigate whether this evidence can be consistent with the standard notion adopted to model bidders’ behavior in auctions, i.e. nash equilibrium. to this end, we consider the following (static) model: a single contract is auctioned off through an ab or abl auction. there are n risk neutral firms that participate in the auction. firm i’s cost of completing the job is given by ci(x ,x , . . . ,xn), where xi is a cost signal privately observed by firm i (xi is the type of firm i). we assume that firm i’s cost is separable in her own and other firms’ signals and linear in xi, i.e. that ci(xi,x−i) = aixi + Γi(x−i), with ai > , ∂Γi/∂xj ≥ , for all i,j = i. firm i’s signal is distributed according to a cumulative distribution function fi(xi), with full support [xi,xi] and density fi(xi). signals are independent. the cost functions as well as the signals’ distributions are common knowledge. firms submit sealed bids formulated in terms of percentage discounts over the reserve price r. the winning firm in ab and abl is determined according to the rules described in the previous section. for convenience, the theoretical analysis presented here is carried on under the restriction that all firms always participate in the auction, because they always find it worthwhile to do so. relaxing it would not alter the results, at least qualitatively. under the above assumptions, we obtain rather sharp predictions on the (bayes-) nash equilibria in the two formats, that we summarize in the following proposition: proposition [equilibrium]. (i) in the ab auction, there is a unique equilibrium in which all firms submit a -discount (irrespective of their signals). (ii) in the abl auction, there exists a continuum of equilibria in which all firms make the same discount d (irrespective of their signals), where d guarantees a positive expected profit even to the firm with the highest expected cost. (iii) in any equilibrium of the abl auction, there is a set k of firms of cardinality k ≥ n−ñ that bid d̄ with strictly positive probability, where d̄ is the largest conceivable bid in the equilibrium and ñ denotes the smallest integer greater than or equal to n/ . moreover, if there is (at least) one firm i ∈ k such that pwi(d̄,δ−i) ≥ pwi(d̄ − ε,δ−i) for ε → +, the probability that at least n − ñ − firms do bid d̄ must be larger than∑k− j=n−ñ− r j/ ∑k− j= r j, where r solves ∑k−(n−ñ− ) j= r j = t , where t = (n− ñ)(n− ñ− )/(n− ñ− ). the common feature of the equilibria of both types of auctions is that they all display a very large degree of pooling, both across firms and within firms. the intuition of this result is straightforward: consider a configuration where bids are largely differentiated across and/or within firms (e.g., all bidding functions are strictly decreasing). in this case, the firm/type notice that the model allows for (ex-ante) heterogeneity across firms. notice also that this model encom- passes the pure private model (Γi = , for all i) and the pure common value model (ci = cj, for all i,j) as special cases. for the proofs, see appendix a. point (i) was already proved in decarolis ( ) for the symmetric private value case. documents de travail du centre d'economie de la sorbonne - . that makes the highest bid will have a very low (if not zero) probability of winning and would rather reduce her bid to increase it. but if she does so unilaterally, another firm/type will become the highest bidder and would rather reduce her bid as well. this process of “escaping from being the highest bidder” comes to an end only when even the highest bidder itself has a sufficiently large probability of winning. in the ab case, this occurs only when all participating firms make a -discount (proposi- tion -(i)). in fact, the firm/type that makes the highest bid d̄ can win the ab auction only if the winning threshold w coincides with d̄ itself and nobody else makes a lower bid (the winning bid is the one closest from below to w), i.e. only when all firms bid d̄. however, if everybody bids d̄ > , any firm still has an incentive to deviate downward: doing so, her probability of winning would jump from /n to . only when all firms make a -discount, such a downward deviation is not admissible and we have reached an equilibrium. in the abl case, instead, the incentive for the highest bidder to deviate downward stops when there is a sufficiently large probability that a large fraction of the other firms makes the same highest bid as well. this discrepancy with respect to the ab format is not due to the different way in which w is computed, but rather to the fact that in abl the winning bid is the one closest from above (rather than below) to w . to see this, consider a firm/type that makes the highest equilibrium bid d̄. now, if less than n− ñ− of the other firms bid d̄, the winning threshold will certainly be below d̄: the highest bid d̄ can be a winning bid (the winning bid is the one closest from above to w , if there is one), but a slight downward deviation d̄ − ε would certainly be profitable: the deviating firm would win in the same circumstances as when she bids d̄, but now she would be the sole winner in case of winning. if, instead, at least n − ñ − of the other firms bid d̄, the winning threshold will certainly coincide with d̄, and a lower bid will give a -probability of winning the auction. hence, bidding d̄ can be an equilibrium bid only if the probability that at least n − ñ − bid d̄ is sufficiently large. proposition -(iii) states this intuition and provides an explicit lower bound to this probability valid when equilibrium satisfies a (mild) restriction: for at least one firm/type that bids d̄, the probability of winning should not increase if this firm slightly deviated downward (notice that this restriction is necessarily satisfied when at least one firm has private cost or when at least one firm’s bidding function is continuous at d̄). to get an idea of the size of this lower bound, notice that, if n = , the probability of observing at least equal bids (at d̄) must be grater than . %. the previous argument should also make it clear why, in these auctions, cost signals do not matter much. the point is that, unlike a standard auction where a higher bid always increases the probability of winning and thus stronger bidders – those with better signals – will bid higher, here to increase the probability of winning a bidder has to make a bid which is neither too high, nor too low; hence, having a better signal is much less of an advantage than in a standard auction. as a consequence, the cost structure plays a less important role in shaping the equilibrium. with interdependent costs, the restriction in proposition -(iii) is not necessarily satisfied, as one firm may still find it unprofitable to slightly deviate downward even if doing so her probability of winning increases: this might be the case if the downward deviation increases the probability of winning when the other firms has worse signals and thus increases the expected cost upon winning. however, if the cost functions are not dramatically affected by a marginal change in the other firms’ signals, then the lower bound should be of the same order as the one stated in proposition -(iii). this line of reasoning applies not only to production costs but, more generally, to any other element that can affect the competitiveness of a firm in the auction. for example, decarolis ( ) and zheng ( ) argue that, in procurement first-price auctions where the true production costs are known only ex-post, riskier firms documents de travail du centre d'economie de la sorbonne - . now, looking at our data, we can rather safely claim that the theoretical predictions described above are inconsistent with the empirical evidence. in the ab auction, bids are far from being equal (the standard deviation of the distribution of bids is, on average, . %) and are significantly greater than zero (the average discount is . %), while equilibrium predicts all bids equal to zero (proposition -(i)). in the abl auction, we can safely reject the all- equal-bids equilibrium of proposition -(ii) (in abl, the average standard deviation of the distribution of bids is . %). moreover, according to proposition -(iii), in abl we should expect to observe a concentration of bids in the right tail of the distribution. this is clearly at odds with our descriptive evidence, according to which the typical bid distribution in an abl auction has its mode below the midpoint of the range of bids. thus, we conclude that nash equilibrium does not seem to be a correct modeling hypoth- esis for the bidding behavior of firms in our dataset. although we do reject the equilibrium hypothesis that all firms are bidding optimally, our intuition is that some of them are doing so, while others are not. one model that supports this intuition is the ch model. this model has been introduced by stahl and wilson ( , ) and further developed and applied by, among others, camerer et al. ( ). strictly related to the ch model is the level-k model introduced by nagel ( ) and applied to first- and second-price auctions by crawford and iriberri ( ) and gillen ( ). the ch model has proved to be particularly fruitful in explaining experimental evidence in beauty-contest games (see the thorough survey by craw- ford et al., ). since average bid auctions are nothing but incomplete information versions of beauty-contest games, this model is a natural candidate to explain our evidence. the ch model holds that individuals (players) involved in strategic situations differ by their level of sophistication, i.e. their ability of performing an iterated process of strategic thinking. the proportion of each level in the population is given by a frequency distribution p(k), where k = , , , . . . is the level of sophistication. level- players are completely unsophisticated and simply play randomly (according to some probability distribution, in general uniform); a level-k player, with k ≥ , believes that her opponents are distributed, according to a normalized version of p(k), from level- to level-(k− ) and chooses her optimal strategy given these beliefs. for example, a level- player believes that all her opponents are of level- ; a level- player believes that her opponents are a mixture of level- and level- players, where the proportion of level- players is p( )/(p( ) + p( )); and so on. in other words, a level-k player’s strategy is optimal conditional on her beliefs, but since her beliefs do not contemplate the presence of players of the same or higher level, the resulting strategy will in general be suboptimal. clearly, a player with a higher level of sophistication has in mind a more comprehensive picture of how other players think and play; hence, we expect – those with lower default costs – make higher discounts, thus generating an adverse selection effect. our model immediately adapts to an environment where firms differ in their default costs, thus predicting that this adverse selection effect almost disappears in average bid auctions. hence, if firms had always played the nash equilibrium, the ca would have paid much more for the works. in particular, given that, in our sample, the average reserve price is about million euro and the average winning is %, the average additional payment by the ca for each project would have been about , euro. moreover, given that in the nash equilibrium, the winner is chosen randomly, the expected market share and market power of each firm would have been the same. in the abl auction, given the multiplicity of equilibria, there is a potential problem of coordination, and one could object that our evidence is just the result of a coordination failure. however, this explanation does not seem fully convincing: first, it would apply to the abl format only, leaving the observed behavior in ab unexplained; second, even restricting this explanation to the abl case, the observed regular asymmetry in the distribution of bids would raise the following question: why do many firms reach a good coordination on relatively low discounts, whereas other firms seems totally unable to coordinate? documents de travail du centre d'economie de la sorbonne - . her strategy to be closer to the optimal one. the logic behind the ch model seems particularly appropriate in our context. in an average bid auction, all bids affect the position of the winning threshold. therefore, it is crucial to have correct guesses on how all other firms are going to bid. but predicting the behavior of all other firms involves answering a complicated chain of questions of the kind: what bid b will a firm make if she thinks others are going to bid a? and what bid c will a firm make if she anticipates that others are going to bid b because they think others are going to bid a? and so on. firms who are able to push this chain of reasoning further will have an advantage over those who perform less steps of such reasoning, in the sense that they will end up with more precise predictions on the actual behavior of others. as a consequence, they are expected to make better (i.e. closer to optimality) bids. solving the ch model in our context for a generic number of firms is problematic. therefore we rely on an asymptotic analysis: this seems sufficiently appropriate in our case, given that the number of participating firms in our dataset is, on average, relatively large (about in ab, about in abl); moreover, we believe that the intuition provided by the asymptotic analysis applies in general, at least under standard hypothesis about the behavior of level- firms. now, let p(k) = pk, k ≥ , be the proportion of level-k firms and suppose that level- firms (independently) choose their bids from the bid distribution g (d) with density g (d) and full support [d,d]. solving the ch-model for n → ∞, we obtain the following main prediction: proposition [cognitive hierarchy]. in the ab auction, in the limit, the (expected) distance of a firm’s bid from a is strictly decreasing in her level of sophistication. in the abl auction, in the limit, the (expected) distance of a firm’s bid from a is strictly decreasing in her level of sophistication. the previous result is pretty intuitive. consider the ab auction: denote by a j and a j the random variables corresponding to the averages a (the winning threshold) and a , conditional on the fact that firms’ levels range from to j (and let a j and a j be their expectations). a level-k firm believes that the other firms range from level to (k − ); hence, to formulate her optimal bid δk, she computes the probability distribution of a k− (which, in turn, depends on a k− ): the intuition suggests that, typically, δk will be “close” (from below) to a k− . now, if δk is indeed close to a k− and given that, by construction, a k− is larger than a k− , then a k and a k, that incorporate also level-k firms’ bids δk, will be larger than a k− and a k− : thus, δk+ , which is close to a k, will be larger than δk. and so on. hence, firms’ bids will be strictly increasing in their level of sophistication; or, equivalently, the distance from a – the expected value of the true winning threshold, i.e. the one computed on the basis of the true distribution of levels in the population of firms – chang et al. ( ), who experimentally studied a simpler average bid auction, focused on the case of three bidders, because “the explicit formulation of a bidder’s winning probability for a general n-bidder game is difficult, if not impossible, to obtain for n ≥ ”(chang et al., , page ). for the proofs, see appendix b. notice that, apart from the assumption of full support for g , we do not make any hypothesis on the shape of p and of g . the second statement holds only under a very mild assumption on the distribution of level- firms’ bids. in some (exceptional) cases, it is possible that the (expected) distance of a firm’s bid from a is constant in her level of sophistication. thus, a is nothing but a k+ , where k is the maximum sophistication level in the population of firms. documents de travail du centre d'economie de la sorbonne - . will be strictly decreasing. proposition states that the intuition described above is correct asymptotically. in fact, when n grows to infinity: (i) the impact of any firm’s bid on a is negligible; (ii) the probability distribution of a k converges to its expected value a k; (iii) there is a very high probability that at least one level- firm bids close to a k. hence, the optimal bid of a level-k firm converges to a k. however, we believe that this result holds also for generic values of n, at least under standard assumptions on g . the same intuition applies also to the abl auction: here a level-k firm, upon choosing her optimal bid, must compute the probability distribution of a k− and a k− , i.e. the lower and upper bounds of the interval from which the winning threshold will randomly be drawn. given that any number in this interval has the same probability to be drawn, we expect a level-k firm to make a bid closer to the expected value (from her viewpoint) of the lower bound: a k− . then, we can apply the same reasoning described above. in this case, however, depending on the distribution of level- firms’ bids, bids can be strictly increasing (this occurs when a > a ) or strictly decreasing (this occurs when a < a ) in the level of sophistication of firms. we expect the latter to be the canonical case: for example, if g is symmetric, then a is necessarily lower than a . in both cases, anyway, the distance from the true expected value of a is strictly decreasing. empirical analysis the previous section has shown that, in our context, the ch model implies that, if firms have different sophistication levels, this should reflect in different bids by them. an heterogeneity in bidding behavior is indeed apparent in our data (see figure ); however, deeper statistical analysis is needed to asses whether such heterogeneity is related to firms’ sophistication in the direction prescribed by the ch model, namely that more sophisticated firms bid closer to the (expected) value of a in ab, of a in abl (proposition ). however, to empirically test proposition , we first need to measure firms’ sophistication level. . a measure of firms’ sophistication in accordance with the fundamental idea of the ch model, a measure of firms’ (i.e. managers’) sophistication should capture their ability of thinking strategically in interactive situations. needless to say, measuring this ability is a complicated task. one possibility would be to rely on some instruments, like some measure of ability, education or professional achievements of firms’ managers. we refrain from following this strategy for two reasons. first, we lack information on firms’ managers or other firms’ characteristics that may proxy strategic ability. second, and most importantly, although innate and/or previously acquired skills certainly matter, the intuition and the literature suggest that individuals can learn to think strategically we performed a series of numerical simulations for different values of n. the results, reported in appendix c, are consistent with the asymptotic result of proposition . in experimental beauty-contest games, burnham et al. ( ) and brañas-garza et al. ( ) showed that subjects who obtained higher scores in a psychometric test of cognitive ability performed better, while chen et al. ( ) showed that subjects’ working memory capacity is positively related to their ch level. goldfarb and xiao ( ), who fitted a ch model to the entry decisions by managers in the us local telephone markets, uncovered a significant positive relationship between managers’ strategic ability on the one hand, their education and experience as ceos on the other. documents de travail du centre d'economie de la sorbonne - . in games as they play over and over again. hence, in a context like ours in which we observe the same firms bidding repeatedly, an out-of-sample static measure of sophistication would miss this learning component. instead, we need a measure of sophistication that can change dynamically within the sample. to this end, we follow a completely different approach: for each auction in our sample, we measure a firm’s sophistication by the relative distance of that firm’s bids from a in ab, from a in abl, in the preceding auctions of that format which she participated in. the idea is that, if the ch model is indeed a good model of firms’ bidding behavior, then we can “invert” the prediction of proposition and take the distance from a or a as an outcome-based measure of her capacity of thinking strategically. specifically, the sophistication index of firm i at the moment in which she participates in the ab auction j is computed as: biddersophabij = ∑ k∈abij ( − ∆ik − ∆mink ∆maxk − ∆ min k ) ( ) where abij is the set of past ab auctions that took place before auction j which firm i participated in, ∆ik is the distance of firm i’s bid from the realized value of a in auction k and ∆mink and ∆ max k are the distances from a of the closest and furthest bid submitted in auction k. notice that each term in the summation in ( ) is between and and takes value ( ) if firm i’s bid was the furthest from (closest to) a in that auction. biddersophablij – the sophistication index of firm i at the moment in which she participates in the abl auction j – is defined similarly, with the caveat that, in this case, the ∆’s are distances from a . the sophistication index ( ) is clearly dynamic, as it changes from one auction to the next depending on the outcome of the last auction. hence, it allows a firm’s level of sophistication to increase or decrease relative to the others. the idea is that firms may learn to think strategically as they gain experience in the auction mechanism. similarly, a firm may lose positions in the sophistication ranking if she does not take into account that other firms may become better strategic thinkers through learning. notice that our sophistication index is auction format-specific, in the sense that participations to ab do not contribute to the firm’s sophistication index when she bids in abl. the idea is that what matters is not experience per se, but experience in that particular strategic situations. figure shows the distributions of bids in ab (left panel) and abl (right panel) for highly and lowly sophisticates firms (i.e. firms with sophistication index above the th percentile vs. those with sophistication index below the th percentile). these graphs point out an heterogeneity in bidding behavior which goes in the direction suggested by proposition . in particular: (i) bids by highly sophisticated firms are more concentrated than those by lowly sophisticated ones; (ii) highly sophisticated firms’ bids are concentrated in the right tail of gill and prowse ( ), studying how cognitive ability (and character skills) influence learning to play equilibrium in a repeated p-beauty contest game, find that more cognitively able subjects make choice closer to equilibrium, converge more frequently to equilibrium play and earn more even as behavior approaches the equilibrium prediction. in some sense, we are adopting an approach similar to revealed preference: we derive the determinants of behavior by induction from the behavior itself. the use of a measure of a firm’s sophistication that weighs all previous participations not only allows to take into account that a firm may learn to think strategically through experience, but also gives more robustness to the results: in a single auction, a firm may bid close to optimality by chance; in a series of auctions, a firm systematically bids close to optimality only if she is a good strategic thinker. by using a cumulative measure, the impact of lucky bids results downsized. documents de travail du centre d'economie de la sorbonne - . figure – discounts in ab (left panel) and abl (right panel): kernel density estimation by highly and lowly sophisticated firms. the distribution of bids in ab and in the left tail in abl. given that our sample contains (by far) more ab than abl auctions, the average value of the sophistication index is, by construction, larger in ab. looking at the whole sample, the frequency distribution of the index displays a higher concentration on low values and fewer observations on high values in both formats, indicating that there are few highly sophisticated (firms that make good bids in a large number of auctions). however, looking only at late years, the distribution tends to be smoother, suggesting that, after some time, more and more firms reach relatively high levels of their sophistication. . estimated equation given the measure of firms’ sophistication just illustrated, we can now introduce and esti- mate a reduced form model to test proposition . the model is the following (we omit the dependence on the auction format, but it is intended that there is one such equation for each format): log |distanceij| = α + β log(biddersophij) + γfi + σfpij + θpj + �ij. ( ) in ( ), the dependent variable, log |distanceij|, is the logarithm of the difference (in absolute value) between firm i’s bid in auction j and the realized value of a [a ] in that ab [abl] auction. biddersophij is firm i’s sophistication index at the moment of participation in auction j, as defined by ( ). fi represents a set of characteristics of firm i that do not vary a two-sample kolmogorov-smirnov test confirms that the distribution of bids by highly and lowly sophis- ticated firms are statistically different in both auction formats. see figures d and d in appendix d. see also figure d in appendix d, which shows the distribution of the sophistication index in ab auctions by firm size and period. interestingly, distributions have similar shapes across firm sizes, although small firms reach lower levels of sophistication by the end of the period. we adopt a log-log model for two reasons: first, the theoretical analysis suggests a non-linear relationship between sophistication and distance from a or a ; second, a log-log model allows to interpret the coefficient attached to the sophistication index as an elasticity. notice that observations with a sophistication index equal to zero are excluded as we require firms to show their bidding ability at least once before entering in the analysis. our main results do not change when we include firms with a sophistication index equal to zero documents de travail du centre d'economie de la sorbonne - . over time, including proxies for size and location. fpij is a set of firms’ characteristics that can vary for each auction. this set includes the backlog of works (i.e. the number of pending public procurement projects a firm has at the moment she bids in auction j; it is a proxy for capacity constraints) and the subcontracting position. pj is a set of variables to control for the characteristics of the auction, such as dimension and complexity of the auctioned work, and the timing of the auction (i.e. year dummy variables to adjust for temporal shocks to the firms and the ca). to reduce concerns about omitted variable problems affecting the relationship between the sophistication index (which is built upon firms’ past behavior in auctions of that format) and firms’ current behavior (e.g., some factors that may influence both the past and current performance of firms are not controlled for), in some specifications we also included firm-fixed effects to adjust for firm-specific characteristics. this enables us to focus on the within firm variation in the sophistication status. however, some relevant characteristics of the firms could vary over the time horizon of our analysis. for this reason, in some specifications we also add firm-year-fixed effects, thus controlling for those characteristics which can vary over time, like, for instance, productivity, financial position, and management skills. this set of fixed effects represents a suitable substitute for the inclusion of firm-year control variables that can be recalled from balance-sheets. . description of the sample table shows summary statistics of the sample used in our estimations, broken down by auction format. the sample of ab auctions includes , bids made by different firms; the sample of abl auctions includes , bids made by different firms. (using log( + biddersoph) as regressor) or when we adopt a log-linear specification (see appendix d, table d ). because we do not have data on firms’ employees or total assets, we construct proxies for firms’ size based on the type of business entity: small = one-man businesses, limited and ordinary partnerships; medium = limited liability companies; large + cooperatives = public corporations and cooperatives. the use of these proxies is motivated by the evidence of a positive correlation between the type of business entity and the size of italian firms (see moretti and valbonesi, , and coviello et al., ). to proxy firms’ location, we take the geographical distance between aosta (i.e. the seat of the ca) and the chief town of the province where the firm has her headquarter (we assign a distance of kilometers to firms located in valle d’aosta, see moretti and valbonesi, ). this variable is also a proxy for firms’ costs (at least for the roadwork contracts, which represent the majority of our auctions). we thank an anonymous referee for this comment. in the procurement literature, the complexity of a project is usually proxied by the its value or the auction’s reserve price, the expected contractual duration of works, dummies for the categories of works included in the project. we use all these proxies in our estimation. notice that the contract value is determined by an engineer employed by the ca, according to a price list that enumerates the standardized costs for each type of work (see decarolis, , and coviello and marinello, , for details on how the ca determines this price). similarly, the expected duration of the work is computed by a ca’s engineer and is stated in the call for tender. the presence of small and micro firms in our dataset makes it impossible for us to use balance-sheet infor- mation to construct additional controls or instrumental variables as these firms are typically under-represented in firm-level balance-sheet-based databases. in fact, a large number of firms is unmatched when we try to merge our dataset with the bureau van dijk’s aida database of italian firms. these descriptive statistics refer to the sample used for the empirical analysis proposed in this section. the original sample was slightly larger ( auctions). the sophistication index is computed on this larger sample to avoid being influenced by partial observations. however, due to missing values in some control variables, our regression analyses are based on the restricted sample. we thus rely on an unbalanced panel of firms. in the ab sample, on average, a firm participated in . auctions: . % of the firms participated in auctions, . % in auctions, . % in auctions, . % in documents de travail du centre d'economie de la sorbonne - . table – estimated sample. ab abl obs. mean sd obs. mean sd firm-auction level: |distance| . . . . biddersoph . . . . backlog . . . . optional subcontracting . . . . auction level: reserve price (euro) , , , . , , , . expected duration (days) . . . . no. bidders . . . . building construction . . . . road works . . . . hydraulic works . . . . firm level: small size . . . . medium size . . . . large size . . . . distance firm-ca (km) . . . . the average auction’s reserve price is around . million euros in both types of auctions and the average number of participating firms per auction is about in ab and in abl. most of the auctions concern road works ( . % of the ab auctions; . % of the abl auctions), hydraulic works ( . % of the ab auctions; . % of the abl auctions) and building construction ( . % of the ab auctions; . % of the abl auctions). the two samples are pretty homogeneous also looking at firms’ other characteristics, such as size (about % are medium or large firms), backlog (upon bidding, firms have, on average, between and pending public procurement projects) and subcontracting position (on average, more than % of the firms have the option to subcontract part of the work). . main estimation result in table , columns ( )-( ), we present our estimation results for the sample of ab auctions. in all specifications, the negative and statistically significant coefficient of log(biddersoph) shows that firms with a higher sophistication index tend to bid closer to a , thus supporting the prediction contained in proposition . this result is robust to the inclusion of covariates at auction-, firm- and firm-auction-level (column ( )), firm-fixed effects (column ( )), and firm- year-fixed effects (column ( )). the inclusion of fixed effects allows us to explore the within firm (or firm-year) variability and to reduce selection-bias and omitted variable problems: in particular, firm-fixed effects can capture the role of any idyosincratic (either innate or previously acquired) component of sophistication peculiar to that firm/manager, while firm- year-fixed effects can capture this same component also for firms whose management changed - auctions, . % in - auctions, . % in - auctions, and . % in more than auctions. in the abl sample, on average, a firm participated in . auctions: . % of the firms participated in auctions, . % in auctions, . % in auctions, . % in - auctions, and . % in more than auctions. documents de travail du centre d'economie de la sorbonne - . during the sample period. table – main results. dependent variable log |distance| auction format ab ab ab abl abl abl ( ) ( ) ( ) ( ) ( ) ( ) log(biddersoph) - . *** - . *** - . *** - . *** - . *** - . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) auction/project controls yes yes yes yes yes yes firm controls yes no no yes no no firm-fe no yes no no yes no firm-year-fe no no yes no no yes firm-auction controls yes yes yes yes yes yes observations , , , , , , r-squared . . . . . . ols estimations. robust standard errors clustered at firm-level in parentheses. inference: (***) = p < . , (**) = p < . , (*) = p < . . auction/project controls include: the auction’s reserve price, the expected duration of the work, dummy variables for the type of work, dummy variables for the year of the auction. firm controls include: dummy variables for the size of the firm, and the distance between the firm and the ca. firm-auction controls include: a dummy variable for the firm’s subcontracting position (mandatory or optional), and a measure of the firm’s backlog. table also reports the results of the regressions for the sample of abl auctions. looking at this sample is illuminating because it allows us not only to test the role of firms’ sophis- tication in a different average bid format, but also to address potential measurement error problems. in fact, while the ab format has long and widely been adopted in italy to award public works, the abl format was introduced in and only in valle d’aosta. hence, while the sophistication index computed for the ab sample does not take into account that firms may have gained experience (and thus sophistication) by participating in ab auctions issued by other italian cas and/or in the past , these measurement error concerns are absent in the abl case. now, also the results for the abl sample are consistent with proposition : the relationship between sophistication index and the distance from a is highly significant and negative. this is true in all the specifications, without fixed effects (column ( )) and with firm- or firm-year-fixed effects (columns ( ) and ( )). interestingly, the estimated coefficient for the sophistication index in the abl auctions indicate a larger negative effect than in ab. a plausible explanation for this could be related to the measurement error problems just dis- cussed. in fact, in ab auctions we might be underestimating the true level of sophistication of firms, especially the most sophisticated ones, which are also those that are most likely to bid also outside valle d’aosta. in appendix d, tables d and d , we show that our main result is confirmed also when: (i) we replace auction covariates with auction-fixed effects; (ii) we add the number of bidders as a proxy for the auction’s competitive pressure; (iii) we estimate an heckman selection model; (iv) the sophistication index is not only auction format- but also work category-specific (i.e. the sophistication acquired in one type of work is irrelevant when that firm bids in an auction for a different type of work). anyhow, we believe that the impact of the experience gained outside valle d’aosta should be limited because the knowledge of the specificity of each market (first of all, its players) is extremely important. moreover, the sophistication accumulated in the past (i.e. before year ) should be captured by the fixed effects. we thank an anonymous referee for suggesting this interpretation. documents de travail du centre d'economie de la sorbonne - . . learning dynamics the previous analysis showed that, in line with the prediction obtained from a ch model, there is a stable negative relationship between firms’ sophistication index and the distance of their bids from a or a . however, that analysis does not say much about the dynamics behind this relationship. in particular, do firms learn to think and bid strategically as they participate in more and more auctions? and, if so, what are the determinants and the characteristics of this learning process? our starting point is the evidence suggested from the kernel density distribution of bids in ab auctions issued during the first ( ) and last ( ) year covered by our dataset. figure shows that, compared to year , bids in are generally much more concentrated on the right side of the distribution, thus suggesting that a learning process is most likely to be taking place. figure – discounts in year and : kernel density estimation. to investigate such process more in depth, we decompose firm i’s sophistication index at auction j into two components. the first component is simply the number of past partici- pations by firm i in auctions of the same format as j and is meant to capture the pure role of experience; we denote this variable by pastpart. the second component is the average performance of firm i in all previous auctions of the same format as j, measured as the average distance of her bid from a or a . this variable, denoted by pastperf, is intended to proxy the degree at which a firm learns to think and bid strategically from her past performance. furthermore, through the fixed effects at the firm-year level, we implicitly take into account also a third component: the stock of strategic skills of a firm/manager in any given year, both innate and acquired in the past. focusing on the sample of ab auctions, table , column ( ), shows the results obtained by estimating a regression model like ( ) with firm-year-fixed effects, where the regressor log(biddersoph) is replaced by log(pastpart). the latter has a negative and statistically significant coefficient, showing that experience does play a role: everything else equal, firms that participate more bid better (i.e. closer to a ) than those that participate less. in column ( ), we add log( + pastperf) to the model specification: interestingly, its coefficient is positive and significant, while the sign of log(pastpart) remains negative and statistically documents de travail du centre d'economie de la sorbonne - . significant. this evidence indicates that the main driver of a firm’s learning over time seems to be the number of past bids and that, at least in ab auctions, a firm tends to learn more from a poor than from a good past performance, as if a poor performance acted as a stimulus for the firm to improve her strategic reasoning in the future. to get deeper evidence on the learning process we investigate whether the fact of winning an auction plays a role. to this end, we introduce the number of past wins (log( +pastwins)) in our model specification. results for the ab auctions indicate that, similarly to what happens with pastperf, a firm seems to learn more from her failures than from her successes (see table , columns ( ) and ( )). the results for the abl auctions confirm that the number of past participations posi- tively affect future bidding performance (the coefficient of log(pastpart) is always negative and significant). however, differently from the ab sample, log( + pastperf) has a negative sign (indicating that firms learn from their good past performances), which turns out to be nonsignificant when firm-year fixed effects are included. interestingly, log( + pastwins) in abl auctions is not statistically significant. this is probably not surprising, as the winner in an abl auction is determined randomly: hence, the fact of winning produces less information than in the ab format. to sum up, the learning process seems to be mainly driven by pure experience: firms improve their capacity of bidding strategically as they participate to more and more auctions. instead, the performance in past auctions has little explanatory power: once firms’ idiosyn- cratic skills are controlled for (through the fixed effects), a better average performance or a larger number of wins in the past either has no impact on bidding behavior in future auctions (in abl) or worsens the capacity of bidding optimally (ab), as if it acted as a negative stimulus to improve strategic thinking. this analysis also allows us to exclude that the re- lationship we uncovered between the sophistication index and bidding performance is simply due to inertia in bidding over time: firms learn how to bid strategically through experience, so those firms that participate more can eventually become more sophisticated than those that participate less, even if the latter were better strategic thinkers initially. given the peculiarity of our dataset characterized by a change in the auction format, and given the results about the learning dynamics just illustrated, it is interesting to understand whether firms in abl auctions drew lessons from what they learned in the ab auctions (in our sample, firms participated both in ab and abl auctions). recall that our sophistication index was, by construction, auction format-specific, in the sense that participations to ab do not contribute to firms’ sophistication when they bid in abl. hence, answering this question is an indirect way to test how restrictive this assumption is. to this end, we focus on the sample of abl auctions and introduce in our model ( ) an additional variable, biddersophab, representing, for each firm, the level of the sophistication index at the end of the period of ab auctions. table , column ( ), shows that a higher sophistication index achieved in the ab period is associated with a lower distance from a in abl. however, when we re-introduce (in column ( )) the firm’s sophistication associated to the abl auctions (biddersoph), the coefficient of the former index is not statistically different from zero, while the auction-specific one is still negative and statistically significant. this result suggests that what really matters notice that, in a specification without firm-year- (or firm-) fixed effects, the interpretation of the coefficient is different: negative coefficients of both log( + pastperf) and log( + pastwins) indicate that, between firms, those with better past performance tend to consistently bid closer to the reference point than those with worse past performance. see appendix d, table d . these results are reported appendix d, table d . documents de travail du centre d'economie de la sorbonne - . table – learning dynamics. dependent variable log |distance| auction format ab ab ab ab abl abl abl abl ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) log(pastpart) - . *** - . *** - . *** ( . ) ( . ) ( . ) log( +pastperf) . *** . *** ( . ) ( . ) log( +pastwins) . *** . *** ( . ) ( . ) log(biddersoph) - . *** - . *** - . *** ( . ) ( . ) ( . ) log(biddersophab) - . ** - . ( . ) ( . ) log(pastpartab) - . . ( . ) ( . ) log( +pastperfab) - . ** - . ( . ) ( . ) auction/project controls yes yes yes yes yes yes yes yes firm controls no no no no yes yes yes yes firm-year-fe yes yes yes yes no no no no firm-auction controls yes yes yes yes yes yes yes yes observations , , , , , , , , r-squared . . . . . . . . ols estimations. robust standard errors clustered at firm-level in parentheses. inference: (***) = p < . , (**) = p < . , (*) = p < . . auction/project controls include: the auction’s reserve price, the expected duration of the work, dummy variables for the type of work, dummy variables for the year of the auction. firm controls include: dummy variables for the size of the firm, and the distance between the firm and the ca. firm-auction controls include: a dummy variable for the firm’s subcontracting position (mandatory or optional), and a measure of the firm’s backlog. is the firm’s strategic ability acquired in that specific type of auction. similar results are obtained when we introduce in the model specification the number of participations (pastpartab) and the average past performance (pastperfab) in ab auctions (columns ( ) and ( )). the coefficients of these two variables are not significant, once we control for the ability acquired by the firm in the abl auctions. discussion the analysis presented in the previous section provides evidence that supports, at least qual- itatively, a non-equilibrium model of bidding behavior by firms in average bid auctions: ob- served deviations from the optimal bid are related to a measure of firms’ capacity of bidding strategically, the sophistication index; this relation goes in the direction predicted by a ch model. therefore, our (continuous) sophistication index proxies the (discrete) ch-level of sophistication by firms. the analysis showed that the relation between sophistication index and bidding behavior is robust to a number of determinants, including auction’s, firm’s and firm-auction’s specific characteristics. most importantly, the relation holds also when we an- alyze the abl format, which is new to the firms and characterized by a stochastic component that makes it more complicated for firms to formulate their bidding strategies. in this section, we show that our explanation is robust to a number of issues that, po- tentially, may undermine it. in particular, we discuss: (i) whether our sophistication index, which we interpret as a measure of strategic thinking ability, may be actually capturing other firms’ structural factors, in particular their competitiveness; (ii) the role of potential documents de travail du centre d'economie de la sorbonne - . cartels jointly bidding in the auctions; (iii) an instrumental variable approach to deal with endogeneity problems; (iv) additional empirical evidence to rule out alternative explanations. . strategic ability vs. competitiveness in standard procurement auctions, the main determinant of a firm’s bid is her production cost: more competitive firms can and do make more aggressive offers, outbidding less competitive ones. a natural question that arises in our context is whether our sophistication index, which, in our view, proxies strategic ability, actually captures some structural competitive feature of the firm: productivity, proximity, or, more generally, any element that translates into a cost advantage. now, notice first that, in our main empirical exercise, we alternatively control for firm’s characteristics (such as size and distance between the firm headquarter and the ca), firm-fixed, or firm-year-fixed effects, as well as for the firm’s subcontracting position (whether the firm must subcontract part of the work or not) and for the number of pending projects the firm is involved in at the time of bidding (which captures her productive capacity). most factors that may generate a competitive advantage/disadvantage of one firm over the others are likely to be accounted for by these variables. however, one might argue that we do not fully control for factors that, similarly to the sophistication index, can vary for each firm within a year or for different types of project. to shed light on these questions, we first estimated a model which includes firm-year-category of work-fixed effects and one with firm-semester-fixed effects: in both models, the coefficient of log(biddersoph) in ab auctions is very much in line with that of our main model specification (see table , columns ( ) and ( ). jofre-bonet and pesendorfer ( ), using a dataset of a sequence of first-price procurement auctions for highway construction in california, showed that the outcome of one auction may affect bids in successive ones because the winner of a previous auction, having committed some or all of her capacity, may have larger costs when participating in the next auctions (because, for example, it will have to rent additional equipment). in our context, this dynamic component seems to be absent, as the variable backlog – the number of pending public procurement projects that a firm has at the moment of bidding – is never significant. our intuition is that, even though it is plausible that having committed capacity can affect firms’ costs, costs simply do not matter much for (optimal) bidding in average bid auctions. our result is robust also to the inclusion of firm-semester-category of work-fixed effects. due to the smaller sample dimension, results are slightly weaker for the abl format (see appendix d, table d ). documents de travail du centre d'economie de la sorbonne - . t a b le – id en ti fi ca ti o n is su es . a u c ti o n fo rm a t a b a b a b a b a b + a b l a b + a b l a b + a b l a b + a b l d e p e n d e n t v a ri a b le lo g |d is ta n ce | lo g |d is ta n ce | d is co u n t lo g |d is ta n ce | lo g (b id d e r s o p h ) lo g (b id d e r s o p h ) lo g |d is ta n ce | lo g |d is ta n ce | q u a n ti le (t h ) i- st a g e i- st a g e ii -s ta g e ii -s ta g e ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a b l - . * * - . * * ( . ) ( . ) lo g (b id d e r s o p h − ) . * * * ( . ) a b l * lo g (b id d e r s o p h − ) - . * * * - . * * * ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s f ir m c o n tr o ls n o n o y e s n o y e s n o y e s n o f ir m -f e n o n o n o n o n o y e s n o y e s f ir m -y e a r- c a te g o ry o f w o rk -f e y e s n o n o n o n o n o n o n o f ir m -s e m e st e r- f e n o y e s n o n o n o n o n o n o f ir m -y e a r- f e n o n o n o y e s n o n o n o n o f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , r -s q u a re d . . . . . . . . h a n se n j (p -v a lu e ) . . o l s e st im a ti o n s in c o lu m n s ( ), ( ) a n d ( ). q u a n ti le re g re ss io n in c o lu m n ( ). s l s in c o lu m n s ( )- ( ). r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n (i n c o lu m n s ( )- ( ) o n ly ). f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . second, we performed an analysis on the level of bids. we start from the conjecture that, if our sophistication index were actually capturing some cost advantage, we would expect to observe either a positive or a null relation between the sophistication index and the level of a firm’s bid. in fact, irrespective of the auction format and of the submitted bid, if a firm’s costs are binding (in the sense that, had her costs been lower, she would have made a different bid), a cost reduction would necessarily result in a higher bid; if, instead, her costs are not binding, a further cost reduction should have no impact on her bid. on the other hand, if our sophistication index captures strategic ability, as we claim, we would expect to observe a negative [positive] relationship between the sophistication index and the bid level for firms making relatively high [low] bids. in fact, in average bid auctions, an improvement in strategic ability would lead firms that bid too high [low] to reduce [increase] their bids towards the optimal bid, which is necessarily somewhere in the interior of the range of submitted bids. now, focusing on the ab sample, our evidence is indeed in line with the latter interpretation and inconsistent with the one based on cost advantage: the effect of the sophistication index on the level of bids, though nonsignificant overall, is negative and significant for those firms bidding the highest (see the result of the regression at the -th quantile in table , column ( )). . potential collusion a very interesting aspect that is worth addressing is related to possible collusive behaviors by firms. in a recent paper, conley and decarolis ( ), using a different dataset of ab auctions, argue that this format can be characterized by the presence of colluding firms which drive the winning threshold to let one member of the cartel win. hence, the evidence on ab auctions would be the result of a cooperative behavior by groups of firms. instead, our approach is totally different: we cannot exclude the presence of colluding firms, but we provide some evidence that also a fully non-cooperative non-equilibrium behavior might be at work. in this sense, our work suggests a complementary explanation. nevertheless, we can provide some arguments supporting the robustness of our findings to the presence of collusion. first, it seems reasonable to assert that, if collusion is at work, it is less likely to be present in abl than in ab auctions: given the inherent uncertainty in the determination of the winning firm, in abl a successful collusive strategy is much more complicated to be implemented. in this sense, the fact that the coefficient of the sophistication index is significant also in abl and larger than in ab (see table ) is reassuring for our explanation. second, without any intention to provide evidence on the presence of cartels in the auctions issued by the regional government of valle d’aosta (note that, unlike in conley and decarolis, in our sample no cartels have been detected and sanctioned by the court; this makes more difficult to study possible collusive behavior in our setting), we tried to isolate the influence of potential collusive groups. to this end, we identified potential cartels following conley and decarolis ( ). in particular, using information on objective links among firms (e.g., firms sharing the same managers, the owners, the location, subcontracting relationship, joint bidding, etc.), the conley and decarolis’ algorithm indicates that, in our sample, potential groups of firms are present. once detected these groups, we included in our baseline model specification two see appendix d, tables d and d , for evidence on abl auctions and further evidence at different quantiles of the distribution of bids. notice that, in both formats, the coefficients of the sophistication index in the quantile regressions exactly match the pattern predicted by a ch model: they are negative [positive] and statistically significant for high [low] bid levels. documents de travail du centre d'economie de la sorbonne - . variables measuring, for each firm and each auction: (i) the number of (potentially) associated firms bidding in that auction; (ii) this number over the total number of firms belonging to that group. our main results continue to hold after the inclusion of these controls. it must anyway be observed that data display a (weak) positive correlation between our index of sophistication and the number of (potentially) associated firms bidding in that auction, both in ab ( . ) and in abl ( . ) auctions. moreover, independent firms – those with no potential associate in the auction – show, on average, lower sophistication than associated firms (the difference is about % in ab and % in abl): these numbers may suggest that, if cartels are present, their members are typically more sophisticated than independent firms. now, to better isolate the role of potential collusion from that of strategic ability, we estimated our baseline model on a restricted sample including only firms with no connection with any other firm participating in that auction (table , column ( )). again, our main result is confirmed, thus supporting the idea that our explanation actually captures bidding behavior by firms, at least for those that act non-cooperatively. . instrumental variables the results presented so far are robust to the inclusion of rich sets of fixed effects and con- trol variables in the estimated equation. however, to further address potential endogeneity concerns, we also consider an instrumental variable (iv) approach, aimed at capturing some exogenous components behind the sophistication index. given that information on several relevant firms’ characteristics (such as information coming from balance-sheets or managerial and organizational structure of the firm) is not available, we choose an approach that jointly combines out-of-sample information and the exogenous change of format from ab to abl. in particular, our identification strategy works as follows. first, we limit our analysis to year and , the last year of adoption of the ab format and the first year of adoption of the abl format, respectively. focusing on such a short period of time, we can reduce omitted variable problems and exploit the variation in the auction format, which, it is worth recalling, took place only in valle d’aosta. second, we consider three instrumental variables for the sophistication index, namely: (i) the dummy variable abl (which takes value equal for abl and for ab) to capture the average overall change in the firms’ sophistication level determined by the change of format; (ii) for each firm, the value of her sophistication index at the end of (biddersoph - ), a proxy for the firm-fixed level of sophistication (relative to the others) acquired out-of-sample; (iii) the interaction between the previous two variables, which accounts for possibly differential effects that the new abl format had on firms’ current sophistication across firms with different levels of past (and out-of-sample) sophistication. first-stage estimation results, reported in table column ( ), show that the coefficients of the three instruments are statistically different from zero (the hansen j-test reported in column ( ) confirms the validity of the instruments). the signs of the coefficients indicate that: (i) the change of format reduced the overall level of bidders’ sophistication (since the sophistication index is specific for each auction format); (ii) the higher the firm’s past (and out-of-sample) sophistication in ab auctions, the higher her level of current sophistication in ab auctions (confirming that experience and past performance have an effect over time within the same auction format); (iii) the heterogeneity in sophistication across firms recorded at estimation results for this analysis are available in appendix d, tables d and d . we really thank francesco decarolis for providing us with his codes and data. documents de travail du centre d'economie de la sorbonne - . the end of is greatly reduced when the new abl format has been adopted. the results of the second-stage estimation (column ( )) confirm a negative and significant relationship between the instrumented current level of sophistication of the firm and the distance of her bids from a in ab and a in abl. notice that these results are robust to the inclusion of firm-fixed effects (table , columns ( ) and ( )). notice also that we control for several auction’s characteristics (such as typology, value and duration of the work), thus reducing the possibility that our instruments affect firms’ bidding behavior through other channels than sophistication. . further evidence beyond the main result that more sophisticated firms bid closer to a in ab, to a in abl, there is additional evidence that supports our interpretation, in the sense that it can easily be reconciled within a ch model, much less so within an alternative explanation. first, notice that firms make relatively lower bids in abl than in ab: this is clear from our data (see figure ); furthermore, if we run a regression on a sample of (min-max rescaled) bids offered both in ab and abl auctions (taking all the covariates included in equation ( )), the coefficient for the abl auction dummy is negative and statistically significant. now, if firms were making equilibrium bids, we should observe the opposite (see proposition ); instead, in a ch model, given the behavior of level- firms, bids made by firms of higher levels are larger in ab than in abl, since, by definition, a k, the (asymptotically) optimal bid by a level-(k + ) firm in ab, is larger than a k. second, data show that not only the average distance from a or a is decreasing in the firm’s sophistication level, but also the variance of this distance follows the same pattern. in fact, running a regression where the dependent variable is the standard deviation of the distance of the auction’s bids from a or a , the coefficient of the auction’s average sophisti- cation index is negative and significant in both formats. moreover, in a regression where the dependent variable is the rolling standard deviation of the distance of a firm’s latest five bids from a or a , the coefficient of the firm’s rolling average sophistication index is negative and significant, even when firm-fixed effects are controlled for. now, while there is no particular reason to expect a relationship between variance of bidding and other firm’s characteristics (e.g. her production costs), a negative relationship between sophistication index and variance of bidding can be justified within a ch model with at least three arguments. first, in a ch model, level- firms bid randomly, while more sophisticated firms bid (essentially) determin- istically. second, if firms make some payoff-sensitive errors, then more sophisticated firms will make more precise bids (with less variance). the intuition is simple: to compute her in appendix d, table d , we show similar estimation results after enlarging the sample of auctions to the period - . this evidence is collected in appendix d, table d . notice that, even if we cannot fully separate in a difference-in-differences style the trend forces from the effects related to the introduction of the (new) abl auction format in valle d’aosta (as we do not observe ab auctions after ), evidence based on a larger sample of procurement auctions (data from coviello et al., ) indicate that, for other italian regions not adopting the abl auction format, the average winning discount in is approximately at the same level as in or it has increased for some northwestern regions. given that, between and , no major changes occurred in in valle d’aosta’s economy conditions and in the procurement regulation (other than the introduction of abl auction format), we can assume that, had valle d’aosta not introduced the abl auction, the trend would have followed a nondecreasing path similar to the one observed in the other regions. see the simulation exercise in appendix c. documents de travail du centre d'economie de la sorbonne - . optimal bid, a level-k firm estimates the distribution of the winning threshold on the basis of the behaviors of level- to level-(k− ) firms. for higher level firms, this distribution has lower variance, being less and less affected by the random behavior of level- firms. third, as it seems reasonable, more sophisticated firms may be less prone to errors than less sophisticated ones. third, data show that the higher the number of participating firms in an auction, the higher [the lower] the value of a [a ] in ab [abl]. this can be seen by looking at descriptive statistics (the simple correlation between the number of participants and a [a ] in ab [abl] is positive [negative]) and by estimating a regression with a or a as the dependent variable and the number of participants and other auction-level controls as regressors. this evidence is consistent with a ch model of bidding behavior: in the viewpoint of a sophisticated firm, who determines her bid on the basis of her own estimates of the distribution of a or a , a lower number of participants increases the variance of this distribution. since the winning bid is the one that gets closer to the winning threshold from below in ab and from above in abl, a sophisticated firm will find it optimal to bid cautiously: in ab, a little below the expected value of a , in abl a little above the expected value of a . as the number of participants increases, the variance of a or a will reduce, and sophisticated firms can be more confident in bidding very close to their expected values. conclusion this paper studies bidding behavior by firms in two versions of average bid auctions adopted by a regional contracting authority in italy for the procurement of public works. our empirical evidence is inconsistent with nash equilibrium behavior, a situation in which all firms are playing their best response to other firms’ bids. we proposed an interpretation based on a non-equilibrium ch model of bidding behavior: more sophisticated firms, being better strategic thinkers, are able to get more accurate beliefs on the behavior of other firms and bid closer to optimality. introducing a dynamic measure of sophistication which takes into account the goodness of a firm’s bids in all past auctions of the same format in our sample, we showed that the main prediction of the ch model is consistent with our data. we also investigated whether and how firms learn to think and bid strategically through experience, showing that both the number of participations and the average past performance explain firms’ performance in future auctions and that this learning process has a convergence path. we finally discussed endogeneity issues and alternative explanations for the observed behavior in the investigated setting (in particular, collusion) by providing some robustness checks on our empirical analysis. the general lesson that can be learned from our work is twofold. first, our paper provides evidence that departures from equilibrium can be significant and persistent also in the field, and even when players are firms and stakes are large. this is likely to be the case especially in complex environments, for example when the profit of one firm depends in a non-obvious way on the decisions made by all other firms. in this case, the equilibrium requirement that all players (firms) have correct beliefs seems particularly, and maybe unrealistically, demanding. second, the ch model and, more generally, models that take into account that strategic thinking may be heterogeneously distributed across economic agents, represent a valid alter- native to equilibrium models in complex games, even outside the lab. moreover, while in the experimental literature on ch models, convergence to equilibrium is usually observed, so documents de travail du centre d'economie de la sorbonne - . that ch models mainly capture initial responses to games, our evidence shows that, even if convergence is taking place, it does so at a slow rate. this is not surprising once one takes into account that, unlike in the lab, in the field the set of players can change continuously over time: new unexperienced firms may enter the stage, others may exit. hence, even though experience may help firms become more sophisticated, the entry of unsophisticated firms may slow down the process of convergence. references [ ] albano, g., bianchi, m., spagnolo, g., . bid average methods in procurement. rivista di politica economica - , - . 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[ ] zheng, c., . high bids and broke winners. journal of economic theory , - . documents de travail du centre d'economie de la sorbonne - . appendix a proof of proposition before proving proposition , for convenience, we restate (more in detail) the assumptions of the model and we prove two lemmas that are used to prove the proposition. the model. a single contract is auctioned off through an ab or abl auction. there are n risk neutral firms that participate in the auction. firm i’s cost of completing the job is given by ci(x ,x , . . . ,xn), where xi is a cost signal privately observed by firm i (xi is the type of firm i). we sometimes write compactly x−i to denote the vector of signals of all firms other than i. we assume that firm i’s cost is separable in her own and other firms’ signals and linear in xi, that ci(xi,x−i) = aixi + Γi(x−i), with ai > , ∂Γi/∂xj ≥ , for all i,j = i. firm i’s signal is distributed according to a cumulative distribution function fi(xi), with full support [xi,xi] and density fi(xi). signals are independent. the cost functions as well as the signals’ distributions are common knowledge. firms submit sealed bids formulated in terms of percentage discounts over the reserve price r. we restrict our attention to situations in which all firms always participate in the auction, because they find it worthwhile to do so. without this restriction, one should take into account the possibility that a firm may decide not to participate for some cost signal realizations: this would complicate the analysis but would not change the results qualitatively. moreover, this restrictions rules out the possibility of non serious bids. now, let di ∈ [ , ] denote firm i’s bid (discount). the expected profit of firm i, type xi, when she participates and bids di and the other firms follow the strategies δ−i is: πi(xi,di,δ−i) = [( −di)r−ci(xi,di,δ−i)] pwi(di,δ−i), where pwi(di,δ−i) is the probability that firm i wins when she bids di and the other firms follow the strategies δ−i, and ci(xi,di,δ−i) is the expected cost of firm i when her signal is xi, she bids di and the other firms follow the strategies δ−i, conditional on the fact that i wins the auction. in symbols, ci(xi,di,δ−i) = aixi + e−i [Γi(x−i) |i wins when strategies are (di,δ−i)] . in the ab auction, the winning bid is the bid closest from below to a . in the abl auction, the winning bid is the bid closest from above to w , provided that this bid does not exceed a . if no bid satisfies this requirement, the winning bid will be the one equal, if there is one, or closest from below to w . in both auctions, if all firms submit the same bid, the contract is assigned randomly. similarly, if two or more firms make the same winning bid, the winner is chosen randomly among them. we first show that, for both auctions, whatever the strategies of the others, a firm has always the possibility of placing a bid that gives her a strictly positive probability of winning the auction. since this result is pretty intuitive, we omit the proof. lemma . consider firm i and denote by δ−i the bidding strategies of the other firms. then, for any δ−i, there exists di such that pwi(di,δ−i) > . this result, together with the restriction of full participation, implies that, in equilibrium, all firms will have a strictly positive probability of winning the auction. documents de travail du centre d'economie de la sorbonne - . we now show that, for both auctions, equilibrium bids are monotone. lemma . let δ = (δ ,δ , . . . ,δn) be a (bayes-) nash equilibrium of either auction for- mats. then, for all i, δi(xi) is weakly decreasing. proof. consider firm i, and let di = δi(xi), d ′ i = δi(x ′ i), be her equilibrium bids when her signals are xi and x ′ i, respectively, with xi < x ′ i. notice first that, in equilibrium, the probability of winning the auction must be weakly decreasing in types. in fact, since di and d′i are equilibrium bids, it must be true that: [( −di)r−ci(xi,di,δ−i)] pwi(di,δ−i) ≥ [ ( −d′i)r−ci(xi,d ′ i,δ−i) ] pwi(d ′ i,δ−i), ( ) and that[ ( −d′i)r−ci(x ′ i,d ′ i,δ−i) ] pwi(d ′ i,δ−i) ≥ [ ( −di)r−ci(x′i,di,δ−i) ] pwi(di,δ−i). ( ) summing them up, we obtain[ ci(x ′ i,di,δ−i) −ci(xi,di,δ−i) ] pwi(di,δ−i) ≥ [ ci(x ′ i,d ′ i,δ−i) −ci(xi,d ′ i,δ−i) ] pwi(d ′ i,δ−i). notice that ci(x ′ i,d,δ−i) −ci(xi,d,δ−i) = ai(x ′ i −xi) > , for all d. hence, we obtain pwi(di,δ−i) ≥ pwi(d′i,δ−i), , in equilibrium, the probability of winning the auction is weakly decreasing in types. we now show that the equilibrium bidding function δi(xi) must be weakly decreasing. now, suppose, by contradiction, that there exists xi,x ′ i, with xi < x ′ i and di < d ′ i. notice that, because, in equilibrium, pwi(di,δ−i) > and pwi(d ′ i,δ−i) > , the lhs and the rhs of ( ) are strictly positive and the lhs of ( ) is weakly positive. hence, multiplying ( ) by ( ), we get [( −di)r−ci(xi,di,δ−i)] [ ( −d′i)r−ci(x ′ i,d ′ i,δ−i) ] ≥[ ( −d′i)r−ci(xi,d ′ i,δ−i) ][ ( −di)r−ci(x′i,di,δ−i) ] , and, after some manipulation, r [ −d′i + ci(x ′ i,d ′ i,δ−i) ][ ci(x ′ i,di,δ−i) −ci(xi,di,δ−i) ] ≥ r [ −di + ci(x′i,di,δ−i) ][ ci(x ′ i,d ′ i,δ−i) −ci(xi,d ′ i,δ−i) ] . now, since ci(x ′ i,d,δ−i) − ci(xi,d,δ−i) = ai(x ′ i − xi) > , for all d, the inequality above reduces to ci(x ′ i,d ′ i,δ−i) −ci(x ′ i,di,δ−i) ≥ d ′ i −di > . hence, we get ci(x ′ i,d ′ i,δ−i) > ci(x ′ i,di,δ−i); but this implies[ ( −d′i)r−ci(x ′ i,d ′ i,δ−i) ] pwi(d ′ i,δ−i) < [ ( −di)r−ci(x′i,di,δ−i) ] pwi(di,δ−i), which contradicts ( ). from the monotonicity property above, we can derive more precise predictions on the (bayes-) nash equilibria in the two formats. let’s start with the ab auction. documents de travail du centre d'economie de la sorbonne - . proposition -(i). in the ab auction, there is a unique equilibrium in which all firms submit a -discount (irrespective of their signals), , for all i, δi(xi) = , for all xi. proof. the proof proceeds in three steps. step . in equilibrium, for all i, there must exist x̂i > xi such that δi(xi) = d̄, for all xi ∈ [xi, x̂i), there must be a strictly positive probability that all firms make the same discount d̄ (where d̄ is the largest conceivable discount in equilibrium, see lemma ). suppose not. let d̄i = maxxi δi(xi) be the largest bid of firm i (from lemma , we know that d̄i = δi(xi)) and let d̄ = maxi d̄i be the maximum conceivable bid in equilibrium. notice that a firm that bids d̄ can win if and only if all other firms bid d̄. however, under our hypothesis, there exists at least one firm that, with probability one, bids less than d̄. hence, at least one of the firms that bid d̄ has a zero probability of winning the auction, but this cannot occur in equilibrium. hence, we have reached a contradiction. step . d̄ = . to see this, notice that a firm bidding d̄ wins if and only if all other firms bid d̄ as well, and in this case every firm will win with probability /n. however, a downward deviation would be profitable in any case: by making a lower bid, any firm will win with probability one when all other participating firms bid d̄ (moreover, with a lower discount). the incentive to make a lower bid does not bite only when a lower bid is not allowed, only when d̄ = . step . for all i, x̂i = xi. this is an immediate consequence of the fact that equilibrium bidding functions are weakly decreasing. consider now the abl auction. in this case there is a multiplicity of equilibria. this discrepancy with respect to the ab format is not much due to the different way in which the winning threshold is computed but rather to the fact that in abl the winning bid is the one closest from above (rather than below) to the winning threshold, provided this bid does not exceed a . proposition -(ii). in the abl auction, there exists a continuum of equilibria in which all firms make the same discount d (irrespective of their signals), for all i, δi(xi) = d for all xi, where d is such that πi(xi,d,δ−i) > for all i and for all xi. proof. if all firms make the same bid d, whatever their signal is, every firm will have a /n chance of winning. if firm i (of any type) makes a bid larger than d, then a will necessarily be equal to d and firm i will have a zero probability of winning as her bid exceeds a . if instead firm i (of any type) makes a bid below d, then w will necessarily be equal to d and the winner will be one of the other firms. again, the probability of winning of firm i will fall to zero. therefore, d is the only bid that guarantees a strictly positive probability of winning. beyond the flat equilibria described above, the abl auction may possibly have other equilibria. in any case, these equilibria display a very large degree of pooling on the maximum discount. the next propositions formalizes this idea. proposition -(iii) - first statement. consider any equilibrium of the abl auction: let d̄ denote the highest conceivable bid in equilibrium, d̄ = maxi δi(xi); let k be the set of firms that bid d̄ with strictly positive probability and let k denote the cardinality of k. then, in any equilibrium, k ≥ n− ñ. proof. the proof proceeds by showing that if k < n− ñ, any firm ∈ k has a profitable (downward) deviation. documents de travail du centre d'economie de la sorbonne - . � k ≤ ñ. in this case, any firm i ∈ k that bids d̄ would have a zero probability of winning the auction (a will necessarily be lower than d̄, hence d̄ cannot be a winning bid); but this cannot occur in equilibrium. � ñ < k < n− ñ. consider any firm i ∈ k with signal xi. this firm bids d̄ and can win the auction if and only if a = d̄ and the winning threshold w is greater than or equal to the largest bid not equal to ( lower than) d̄. if this occurs, the winner will be chosen randomly from those firms that bid d̄. hence, the expected profit of firm i, type xi is πi(xi, d̄,δ−i) = k− ∑ j=ñ ( − d̄)r−ci(xi, d̄,δ−i|j = j) j + pr(d̄ is winning bid|j = j)pr(j = j), where j denotes the number of firms in k, beyond firm i, that do bid d̄. consider now what happens when firm i, type xi bids slightly less than d̄. in this case, her expected profit would at least be πi(xi, d̄−ε,δ−i) ≥ k− ∑ j=ñ [( − d̄ + ε)r−ci(xi, d̄−ε,δ−i|j = j)]pr(d̄−ε is winning bid|j = j)pr(j = j). in order for d̄ to be the equilibrium bid of firm i, type xi, it must hold that πi(xi, d̄,δ−i) ≥ πi(xi, d̄−ε,δ−i), for all ε > . in the limit, this implies that k− ∑ j=ñ − j j + [( − d̄)r−ci(xi, d̄,δ−i|j = j)]pr(d̄ is winning bid|j = j)pr(j = j) ≥ . ( ) notice that pr(d̄ is winning bid|j = j) must be strictly greater than zero for at least some j (if not, firm i, type xi, would have a zero probability of winning and would rather deviate downward or not participate). hence, if the term between square brackets in ( ) is positive for all j (notice that individual rationality implies that at least one of these terms must be strictly positive), then the inequality above cannot be satisfied. however, consider the possibility that the term between square brackets in ( ) is positive for some j and strictly negative for the others. notice that, because all bidding functions are weakly decreasing, ci(xi, d̄,δ−i|j = j) must be weakly decreasing in j. hence, there must be some n̂ such that the term between square brackets is strictly negative for ñ ≤ j ≤ n̂, and positive for n̂ < j ≤ k− . in light of this, inequality ( ) can be written as n̂∑ j=ñ j j + [ci(xi, d̄,δ−i|j = j) − ( − d̄)r]pr(d̄ is winning bid|j = j)pr(j = j) ≥ k− ∑ j=n̂+ j j + [( − d̄)r−ci(xi, d̄,δ−i|j = j)]pr(d̄ is winning bid|j = j)pr(j = j). notice that the lhs of the inequality above (which now contains only strictly positive terms) is necessarily lower than n̂∑ j=ñ n̂ j + [ci(xi, d̄,δ−i|j = j) − ( − d̄)r]pr(d̄ is winning bid|j = j)pr(j = j), notice that, for j ≤ n− ñ− , when ε → , pr(d̄−ε is winning bid|j = j) → pr(d̄ is winning bid|j = j), and ci(xi, d̄−ε,δ−i|j = j) → ci(xi, d̄,δ−i|j = j). documents de travail du centre d'economie de la sorbonne - . and the rhs is necessarily strictly greater than k− ∑ j=n̂+ n̂ j + [( − d̄)r−ci(xi, d̄,δ−i|j = j)]pr(d̄ is winning bid|j = j)pr(j = j). but this would imply that πi(xi, d̄,δ−i) < , which contradicts the fact that this is an equilibrium. proposition -(iii) - second statement. in any equilibrium of the abl auction in which there is at least one firm i ∈ k such that pwi(d̄,δ−i) ≥ pwi(d̄−ε,δ−i) for ε → +, the probability that at least n− ñ− firms do bid d̄ must be larger than ∑k− j=n−ñ− r j/ ∑k− j= r j, where r solves ∑k−(n−ñ− ) j= r j = t , where t = (n− ñ)(n− ñ− )/(n− ñ− ). proof. consider firm i, type xi. this firm bids d̄ and wins the auction with probability pwi(d̄,δ−i) = n−ñ− ∑ j=ñ pr(d̄ is winning bid|j = j)pr(j = j) j + + k− ∑ j=n−ñ− pr(j = j) j + , where j is the number of firms in k that do bid d̄ (beyond firm i itself). notice that, when j ≥ n− ñ− , the winning threshold w is necessarily equal to d̄. suppose that firm i, type xi, bids slightly less than d̄. her probability of winning the auction would at least be pwi(d̄−ε,δ−i) ≥ n−ñ− ∑ j=ñ pr(d̄−ε is winning bid|j = j)pr(j = j) +pr(d̄−ε is winning bid|j = n− ñ− )pr(j = n− ñ− ). notice that, when j > n− ñ− , w will be equal to d̄ and d̄−ε cannot be a winning bid. by assumption, for sufficiently small ε, it must be pwi(d̄,δ−i) ≥ pwi(d̄−ε,δ−i). in the limit, this inequality becomes n−ñ− ∑ j=ñ pr(d̄ is winning bid|j = j)pr(j = j) j + + k− ∑ j=n−ñ− pr(j = j) j + ≥ n−ñ− ∑ j=ñ pr(d̄ is winning bid|j = j)pr(j = j) + pr(j = n− ñ− ), or, equivalently, k− ∑ j=n−ñ− pr(j = j) j + − n− ñ− n− ñ− pr(j = n−ñ− ) ≥ n−ñ− ∑ j=ñ j j + pr(d̄ is winning bid|j = j)pr(j = j). ( ) notice that the rhs of the ( ) is positive. hence, in order for ( ) to be satisfied, it must necessarily hold that k− ∑ j=n−ñ− pr(j = j) j + ≥ n− ñ− n− ñ− pr(j = n− ñ− ). ( ) documents de travail du centre d'economie de la sorbonne - . notice that the lhs of the ( ) is lower than k− ∑ j=n−ñ− pr(j = j) n− ñ . hence, in order for ( ) to be satisfied, it must necessarily hold that k− ∑ j=n−ñ− pr(j = j) ≥ (n− ñ)(n− ñ− ) n− ñ− pr(j = n− ñ− ). ( ) our goal is to find a lower bound to ∑k− j=n−ñ− pr(j = j) knowing that ( ) must necessarily hold. notice that the number j of firms that bid d̄ (beyond firm i) is the number of successes in k − independent trials, where the probability of success in the l-th trial is pl = fl(x̂l); hence, j is a random variable with poisson binomial distribution. now, denote by rj the ratio pr(j=j) pr(j=j− ) . inequality ( ) can be rewritten as rn−ñ− ≥ t + ∑k− j=n−ñ ∏j i=n−ñ ri , ( ) where t = (n− ñ)(n− ñ− )/(n− ñ− ). it can easily be shown that, if rj = t, then rj− > t, rj is increasing in j. hence, we have the following constraints: rk− > rk− > ... > r . ( ) finally, it must be that ∑k− j= pr(j = j) = , which can be rewritten as pr(j = n− ñ− ) = ∏n−ñ− i= ri + ∑k− j= ∏j i= ri . ( ) our objective is to find a lower bound to ∑k− j=n−ñ− pr(j = j), we want to solve inf {ri} pr(j = n− ñ− )   + k− ∑ j=n−ñ j∏ i=n−ñ ri   under the constraints ( ), ( ), ( ). the solution to the above problem is no greater than the solution to the problem inf {ri} pr(j = n− ñ− )   + k− ∑ j=n−ñ j∏ i=n−ñ ri   under the constraints ( ), ( ) and under the constraint rk− ≥ rk− ≥ . . . ≥ r . ( ) documents de travail du centre d'economie de la sorbonne - . (we replaced ( ) with a looser constraint). it’s easy to show, that, in the solution to the above problem all constraints ( ) and ( ) are binding. hence, the objective function is minimized at r = r = . . . = rk − = r, with k−(n−ñ− )∑ j= rj = t, and the minimum is ∑k− j=n−ñ− r j/ ∑k− j= r j. documents de travail du centre d'economie de la sorbonne - . b proof of proposition proposition can be easily obtained as a corollary of the following two lemmas that precisely characterize the asymptotic (optimal) behavior of level-k firms, k ≥ . lemma (i) consider the ab auction. let δ (n) k (x) be the bidding strategy of a level-k firm, type x, for k ≥ , when there are n firms and the other firms’ levels range from to k− (and the proportion of level-j firms is pj/ ∑k− i= pi). then, as n → ∞, δ (n) k (x) → a k− for all x, where: – a = e[d |a < d < d[ ]]; – for j ≥ , a j = (p e[d |a j < d < d[ ]] + ∑j i= pia i− [a i− >a j])/(p +∑j i= pi [a i− >a j]); – a = e[d |d[ ] < d < d[ ]]; – for j ≥ , a j = (p a + ∑j i= pia i− )/( ∑j i= pi); – d[ ] and d[ ] are the -th and -th percentile of g (d), g (d[ ]) = . and g (d[ ]) = . . (ii) consider the abl auction. let δ (n) k (x) be the bidding strategy of a level-k firm, for k ≥ , when there are n firms and the other firms’ levels range from to k− (and the proportion of level-j firms is pj/ ∑k− i= pi). then, as n →∞, δ (n) k (x) → a k− for all x, where: – for j ≥ , a j = (a j + d[ ])/ ; – a = e[d |a < d < d[ ]]; – for j ≥ , a j = (p e[d |a j < d < d[ ]] + ∑j i= pia i− [a i− >a j])/(p +∑j i= pi [a i− >a j]); – a = e[d |d[ ] < d < d[ ]]; – for j ≥ , a j = (p a + ∑j i= pia i− )/( ∑j i= pi); – d[ ] and d[ ] are the -th and -th percentile of g (d), g (d[ ]) = . and g (d[ ]) = . . proof. (i) consider the ab auction. let a k− and a k− be the value of a and a when firms’ levels range from to k− (with frequencies (p / ∑k− i= pi, . . . , pk− / ∑k− i= pi)), level- firms bid according to g (d) and level-j firms, < j ≤ k − bid their best response to their own beliefs. consider a level- firm first. in order to choose her optimal bid, a level- firm has to compute the probability distribution of the winning threshold a , which in turn depends on a . now, a = ∑n−ñ j=ñ+ d (j) /(n − ñ), where d (j) is the j-th lowest bid by the level- firms. let yi, i = , . . .n be a sequence of i.i.d. random variables with distribution gy (y) = g (y|d[ ] < d < d[ ]). the crucial thing to show documents de travail du centre d'economie de la sorbonne - . is that, when n → ∞, a converges almost surely to a = e[y ]. to see this, notice first that, by the strong law of large numbers, ∑n j= d (j) /n a.s.−−→ e[d ], and, consequently, d (ñ) a.s.−−→ d[ ], d (n−ñ+ ) a.s.−−→ d[ ]. now, let m = min{m ∈ , . . . ,n : d (m) > d[ ]} and mn = max{m ∈ , . . . ,n : d (m) < d[ ]}. notice that ∑m j=m d (j) /(m −m + ) converges almost surely to e[y ] (because the random variables d(l) , with l ∈ [m ,m ] have the same distributions as the yi’s). given this, in order to show that a a.s.−−→ e[y ], it is sufficient to show that the difference a − ∑m j=m d (j) /(m −m + ) converges almost surely to . now, this difference can be written as a − ∑m j=m d (j) n− ñ + ∑m j=m d (j) n− ñ − ∑m j=m d (j) m −m + ( ) notice that, since d ∈ [d,d] ⊆ [ , ], the first two addends in ( ) are certainly no greater than |m − ñ| + |m − (n− ñ) + | n− ñ , and this term goes to almost surely. the last two terms in ( ) can be written as∑m j=m d (j) m −m + ( m −m + n− ñ − ) . notice that the first fraction converges to e[y ], and that (m −m + )/(n− ñ) goes to . hence, expression ( ) converges to almost surely. in a similar way, one can show that a converges almost surely to a = e[d |a < d < d[ ]]. moreover, notice that, because g (d) has full support, when n grows to infinity, for all ε > , pr(d ∈ (a − ε,a )) → . hence, as n increases, to get a positive chance of winning, a level- has to make a bid which is closer and closer to the expected value (from her viewpoint) of the winning threshold a , δ (n) (x) → a , for all x. consider now a level- firm. from her point of view, the winning threshold is a , which, in turn, depends on a . reasoning in the same way as before, and given that level- firms’ bids tend to a , one show that a converges almost surely to a = (p a + p a )/(p + p ), and a converges almost surely to a = (p e[d |a < d < d[ ]] + p a )/(p + p ). as n increases, to get a positive chance of winning, a level- has to make a bid which is closer and closer to the expected value (from her viewpoint) of the winning threshold a , δ (n) (x) → a , for all x. proceeding recursively, it is easy to show that, for all k ≥ , a k converges almost surely to a k = (p a + ∑k i= pia i− )/( ∑k i= pi), and a k converges almost surely to a k = p e[d |a k < d < d[ ]] + ∑k i= pia i− [a i− >a k] p + ∑k i= pi [a i− >a k] . hence, δ (n) k (x) → a k− for all x. documents de travail du centre d'economie de la sorbonne - . (ii) apart from minor differences, the proof is the same for the abl auction. just one point is worth mentioning: from the point of view of a level-k firm, when n grows to infinity, the interval from which the winning threshold is drawn, converges to [a k− ,a k− ]. now, since every number in this interval has the same probability of being extracted, a level-k firm will bid closer and closer to the lowest value of this interval, δ (n) k (x) → a k− . lemma (i) in the ab auction, a k− < a k, for all k ≥ . (ii) in the abl auction: if a < (d[ ] + a )/ , then a k− < a k for all k ≥ ; if a > (d[ ] + a )/ , then a k− > a k for all k ≥ ; if a = (d[ ] + a )/ , then a k− = a k for all k ≥ . proof. (i) notice first that, by construction, for all k, a k < a k: in fact, a k is a weighted average of numbers that are strictly greater than a k. second, for all k ≥ , a k− < a k < a k− : for k = , this is fairly obvious; for k > , notice that, since a k− = (p a + ∑k− i= pia i− )/ ∑k− i= pi, we have that k− ∑ i= pia k− = p a + k− ∑ i= pia i− . using this and substituting into the expression for a k, we get a k = ∑k− i= pia k− + pka k− ∑k i= pi . hence, a k is a weighted average of a k− and a k− , but since a k− < a k− , it must be a k− < a k < a k− . we now show, by induction, that, if a j− < a j for all j ≤ k, then a k < a k+ . so, assume a j− < a j for all j ≤ k, k ≥ ; let s = min j = , . . . ,k − |a k < a j and let t = min j = , . . . ,k|a k+ < a j. notice that, necessarily, it must be s ≤ t; when s < t, we have a k = p e[d |a k < d < d[ ]] + ∑k i=s+ pia i− p + ∑k i=s+ pi = p e[d |a k < d < d[ ]] + ∑t i=s+ pia i− + ∑k i=t+ pia i− p + ∑t i=s+ pi + ∑k i=t+ pi . hence, (p + t∑ i=s+ pi + k∑ i=t+ pi)a k − t∑ i=s+ pia i− = p e[d |a k < d < d[ ]] + k∑ i=t+ pia i− . ( ) documents de travail du centre d'economie de la sorbonne - . now, notice that, since a k+ > a k, it must be a k+ = p e[d |a k+ < d < d[ ]] + ∑k+ i=t+ pia i− p + ∑k+ i=t+ pi > p e[d |a k < d < d[ ]] + ∑k+ i=t+ pia i− p + ∑k+ i=t+ pi . using ( ), the last inequality becomes a k+ > (p + ∑t i=s+ pi + ∑k i=t+ pi)a k − ∑t i=s+ pia i− + pk+ a k p + ∑k+ i=t+ pi = (p + ∑k i=t+ pi + pk+ )a k + ∑t i=s+ pi(a ka i− ) p + ∑k+ i=t+ pi =a k + ∑t i=s+ pi(a ka i− ) p + ∑k+ i=t+ pi ≥a k. when s = t, the whole derivation above goes through with the only difference that all terms involving ∑t i=s+ are absent. to complete the proof, we have to show that a < a , which is fairly obvious, since a = (p e[d |a < d < d[ ]] + p a )/(p + p ), is a wighted average of a and a number (e[d |a < d < d[ ]]) strictly greater than a . (ii) the proof for the abl auction follows exactly the same line as the previous one with one caveat: if a < a , we have that the sequence of a k’s is strictly increasing; if, instead, a > a , the sequence of a k’s is strictly decreasing (in the proof, all inequalities are reversed); of course, it is in principle possible that a = a , in which case the sequence of a k’s is constant. (typically, we expect a > a : in fact, a is the average between d[ ] and a , and the latter is no greater than d[ ]; hence, if g is symmetric, a is necessarily below the mean of g (d). to have a ≤ a , g (d) must be heavily skewed.) the previous result immediately implies proposition , that, for convenience, is reported below. proposition . in the ab auction, in the limit, the (expected) distance of a firm’s bid from a is strictly decreasing in her level of sophistication. in the abl auction, in the limit, the (expected) distance of a firm’s bid from a is strictly decreasing in her level of sophistication. proof. take the ab auction. if we denote by kmax the highest level of sophistication in the population of firms, then: if kmax is finite, the expected value of a , when n → ∞, is simply a kmax+ ; if not, the expected value of a , when n →∞, is limk→∞a k. in any case, a k < e[a ], for all k. this, together with the fact that the sequence of a k’s is strictly to be precise, this proposition holds only when a = a ; when a = a , the (expected) distance of a firm’s bid from a is constant in her level of sophistication. documents de travail du centre d'economie de la sorbonne - . increasing, implies that the distance between a k (which is the optimal bid of a level-k + firm) and e[a ] is strictly decreasing in k. for the abl auction, the proof is analogous. documents de travail du centre d'economie de la sorbonne - . c numerical simulations in this section, we present the results of some simulation exercises from a ch model of bidding behavior in ab and abl. the purpose of this exercise is twofold: on the one hand, it shows that the main prediction of the ch model – the distance of a firm’s bid from a in ab, from a in abl, is strictly decreasing in her level of sophistication – does not hold only asymptotically (as was proved in proposition ), but also for finite n; on the other hand, it provides support to the additional empirical evidence presented in subsection . . the simulations are run under the following assumptions and parametrization: we fix the reserve price to and assume that firms’ costs are private and independently and identically distributed according to a uniform distribution on the interval [c = , c̄ = ], with increments of . . we assume that firms’ levels of sophistication range from to and that they are distributed according to a truncated poisson with parameter λ. level- firms are assumed to draw their bids from a uniform distribution over the interval [ , . ]. this assumption is roughly consistent with our evidence (the minimum and maximum discounts observed in our sample are and . in ab and . and . in abl) and ensures that level- firms will never play dominated strategies. level- firms choose their bids to maximize their expected payoffs under the belief that all other firms are level- , while level- firms choose their bids to maximize their expected payoffs under the belief that other firms are a mixture of level- and level- . given the behavior of level- , level- and level- firms, we compute the expected value of a (for the ab auction) or a (for the abl auction), and, for each level, the expected value and the variance (in square brackets) of the distance between their bids and a or a . since our objective is to check the consistency of the results of the simulations with real data, we must allow for errors. hence, the distance from a or a is computed supposing that level- and level- firms’ bids are subject to logistic errors: every bid is played with positive probability but the probability that a level-l firm (l = , ) with cost c bids d̂ is exp(ηΠl(d̂; c))/ ∑ d exp(ηΠl(d; c)), where Πl(d; c) is the expected payoff of a level-l firm when her cost is c and she bids d, and where η denotes the error parameter (with η = meaning random behavior and η →∞ meaning no errors). we also computed the truly optimal bid, , the bid that would maximize the expected payoff of a firm who has fully correct beliefs about the behavior of other firms. proposition showed that, when n →∞, this truly optimal bid converges to a in ab, to a in abl, but for finite n, it may be different. hence, it is important to verify whether a and a are indeed good proxies for the optimal bid. the results of the simulations are reported in tables c -c , for different values of the parameter of the distribution of levels (λ = . , , ), of the number of firms (n = , , ) and of the parameter of the error distribution (η = . , , ). we consider only level- and level- firms because experimental evidence has shown that the majority of subjects performs no more than levels of iteration (see, e.g., crawford et al. ). hence, the probability that a firm’s level of sophistication is l (l = , , ) is equal to eλλl/l∑ i= eλλi/i = λl/l +λ+λ / . hence, a higher λ means that firms are, on average, more sophisticated. in this sense, level- firms have at least a minimum degree of rationality. their random behavior could be interpreted as the consequence of a total absence of any precise beliefs about the behavior of others. the assumption that level- players do not play dominated strategies represents a small departure from the standard ch-literature. however, we believe that this represents a reasonable assumption in real world applications: all firms, also the most naive ones, should easily realize that it is not a good idea to offer a discount that would not allow it to cover the cost of realizing the work. in a similar vain, goldfarb and xiao ( ), in their estimated ch-model of entry decisions by firms, endow level- firms with a minimum degree of rationality. documents de travail du centre d'economie de la sorbonne - . table c – simulation results for the ab auction with η = . . distance from a opt. distance from opt. bid n λ a level level level bid level level level . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . - . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] table c – simulation results for the ab auction with η = . distance from a opt. distance from opt. bid n λ a level level level bid level level level . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . - . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] table c – simulation results for the ab auction with η = . distance from a opt. distance from opt. bid n λ a level level level bid level level level . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . - . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] looking at the results of these numerical simulations, we detect some regularities, that we summarize below. (a) for all values of n, λ, and η, the optimal bid (, the bid that maximizes the expected payoff of a firm that has fully correct beliefs about the behavior of all other firms) is essentially unaffected by the private cost. in fact, of the possible combinations of parameters considered, there are only two cases in which the optimal bid is not constant documents de travail du centre d'economie de la sorbonne - . table c – simulation results for the abl auction with η = . . distance from a opt. distance from opt. bid n λ a level level level bid level level level . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] table c – simulation results for the abl auction with η = . distance from a opt. distance from opt. bid n λ a level level level bid level level level . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] table c – simulation results for the abl auction with η = . distance from a opt. distance from opt. bid n λ a level level level bid level level level . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] . . [ . ] . [ . ] . [ . ] in the private cost: in ab, with η = . , n = , λ = . and in ab, with η = , n = , λ = . . moreover, in these two cases, the range of the optimal bidding function is pretty narrow (about %). this confirms the intuition that, in these auctions, costs do not matter much for bidding. (b) for all values of n, λ, and η, the optimal bid is extremely close to the expected value documents de travail du centre d'economie de la sorbonne - . of a in ab, of a in abl. this supports the intuition that, in these auctions, a and a are good proxies for the optimal bid, even when n is finite. (c) for all values of n, λ, and η, the distance of a firm’s bid from the expected value of a in ab, of a in abl, is decreasing in her level of sophistication. hence, the main theoretical prediction of the asymptotic ch model (proposition ) seem to hold also when n is relatively small. (d) for given n, λ, and η, level- and level- firms’ bids are, on average, lower in abl than in ab. this fact is consistent with the empirical evidence discussed in subsection . . (e) in either auction, for all values of n, λ, and η, the variance of the distance from a or a is decreasing in the sophistication level of the firm. this fact is consistent with the empirical evidence discussed in subsection . . (f) for given λ and η, the optimal bid and the expected value of a are increasing in n in ab, the optimal bid and the expected value of a are decreasing in n in abl. this fact is consistent with the empirical evidence discussed in subsection . . documents de travail du centre d'economie de la sorbonne - . d additional empirical evidence this section presents additional empirical evidence, both descriptive and inferential, recalled and commented in sections and of the paper. in particular: � figures d , d and d report descriptive evidence about the distribution of the sophis- tication index over time and by firm size; � table d , columns ( ) and ( ), show that our main empirical result does not change when we amend our baseline model ( ) including in the estimation those firms with a sophistication index equal to (replacing log(biddersoph) with log( + biddersoph)); � table d , columns ( ) and ( ), show that our main empirical result does not change when we amend our baseline model ( ) adopting a log-linear specification instead of a log-log one; � table d , columns ( ) and ( ), show that our main empirical result does not change when we amend our baseline model ( ) adding the number of bidders as a control variable; � table d , columns ( ) and ( ), show that our main empirical result does not change when we amend our baseline model ( ) replacing auction controls with auction-fixed effects; � table d , columns ( )-( ), show, for the ab auctions, that our main empirical result does not change when we adopt a two-step heckman model to control for selection bias problems; � table d , columns ( )-( ), show, for the ab auctions, that our main empirical result does not change when the sophistication index is category-specific: when a firm partic- ipates in auction j, only her performances in past auctions of the same format and of the same category of work as j are considered in the computation of her sophistication level; � table d , columns ( )-( ), show, for the ab sample, the estimation results when firm- and firm-year-fixed effects are not included in the model discussed in subsection . ; � table d , columns ( )-( ), show, for the ab sample, the estimation results when firm- year-fixed effects are replaced by firm-fixed effects in the model discussed in subsection . ; � table d , columns ( )-( ), show, for the abl sample, the estimation results of the model discussed in subsection . ; � table d , columns ( )-( ), show, for the abl sample, the estimation results when firm- and firm-year-fixed effects are not included in the model discussed in subsection . ; � table d , columns ( )-( ), show, for the abl sample, the estimation results when firm- year-fixed effects are replaced by firm-fixed effects in the model discussed in subsection . ; documents de travail du centre d'economie de la sorbonne - . � table d shows that our main empirical result does not change when we amend our baseline model ( ) replacing firm- or firm-year-fixed effects with firm-semester or firm- category of work- or firm-category of work-semester- or firm-category of work-year-fixed effects; � table d shows the estimation results of a model in which the dependent variable is the level of bids; � table d shows the estimation results of quantile regression models in which the de- pendent variable is the level of bids; � table d shows that our main empirical result does not change when we control for potential cartels in ab; � table d shows that our main empirical result does not change when we control for potential cartels in abl; � table d shows that the results of our iv regressions are unchanged when we focus on the longer period - ; � table d , columns ( ) and ( ), show that bids are, on average, lower in abl than in ab; � table d , column ( ), shows that a in ab increases with the number of participating firms; � table d , column ( ), shows that a in abl decreases with the number of participat- ing firms; � table d , columns ( )-( ), show that the standard deviation of the average distance between bids and a [a ] in an ab [abl] auction is decreasing in the average sophis- tication level of the firms participating in that auction. documents de travail du centre d'economie de la sorbonne - . figure d – distribution of the sophistication index in ab. figure d – distribution of the sophistication index in abl. documents de travail du centre d'economie de la sorbonne - . figure d – distribution of the sophistication index in ab by firm size. documents de travail du centre d'economie de la sorbonne - . t a b le d – r o b u st n es s ch ec k s o n th e b a se li n e m o d el sp ec ifi ca ti o n . d e p e n d e n t v a ri a b le : lo g |d is ta n c e | a u c ti o n fo rm a t a b a b a b a b a b l a b l a b l a b l ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g ( + b id d e r s o p h ) - . * * * - . * * * ( . ) ( . ) b id d e r s o p h - . * * * - . * * * ( . ) ( . ) lo g (b id d e r s o p h ) - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s n o y e s y e s y e s n o f ir m c o n tr o ls n o n o n o y e s n o n o n o y e s f ir m -y e a r f e y e s y e s y e s n o y e s y e s y e s n o a u c ti o n -f e n o n o n o y e s n o n o n o y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , r -s q u a re d . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n , a n d , in c o lu m n s ( ) a n d ( ), th e n u m b e r o f b id d e rs . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r fi rm si z e a n d fo r th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – a b a u ct io n s: se le ct io n b ia s p ro b le m s (t w o -s te p h ec k m a n m o d el ) a n d ca te g o ry -s p ec ifi c so p h is ti ca ti o n in d ex . d e p e n d e n t v a ri a b le : lo g |d is ta n c e | p r. p a rt . lo g |d is ta n c e | p r. p a rt . lo g |d is ta n c e | ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) - . * * * - . * * * . * * * ( . ) ( . ) ( . ) lo g (t im e t o b id ) . * * . * * * ( . ) ( . ) lo g (b id d e r s o p h i n c a t) - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) lo g ( + b id d e r s o p h i n c a t) - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s f ir m -c o n tr o ls y e s y e s y e s y e s y e s y e s n o n o n o n o f ir m -f e n o n o n o n o n o n o y e s y e s n o n o f ir m -y e a r f e n o n o n o n o n o n o n o n o y e s y e s f ir m -a u c ti o n c o n tr o ls n o n o n o n o y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , , , r -s q u a re d . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r fi rm ’s si z e a n d fo r th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . t h e a n a ly si s fo c u se s o n a b a u c ti o n s fo r ro a d w o rk s b e c a u se th e y re p re se n t th e la rg e st sh a re o f p ro je c ts in o u r d a ta ( a u c ti o n s) . o l s re g re ss io n in c o lu m n ( ) sh o w s th e c o e ffi c ie n t o f b id d e r s o p h e st im a te d o n th e su b sa m p le o f ro a d w o rk s. t h e p o te n ti a l m a rk e t fo r ro a d w o rk s is d e fi n e d a s th o se fi rm s th a t, a c c o rd in g to o u r d a ta se t, b id a t le a st o n c e fo r ro a d w o rk s in a g iv e n y e a r. a s a n e x o g e n o u s in st ru m e n t th a t is re la te d to th e p ro b a b il it y o f fi rm s’ p a rt ic ip a ti o n b u t h a s a n in fl u e n c e o n ly o n th e c o st o f p a rt ic ip a ti o n , w e u se t im e t o b id , w h ic h is th e le n g th o f ti m e b e tw e e n th e d a te w h e n th e p ro je c t is a d v e rt is e d a n d w h e n th e b id le tt in g o c c u rs (t h is in st ru m e n t is a ls o u se d b y g il a n d m a ri o n , a n d m o re tt i a n d v a lb o n e si ). t h e h y p o th e si s is th a t th e lo n g e r th e ti m e b e tw e e n th e b e g in n in g o f p ro je c t’ s p u b li c it y a n d th e d e a d li n e fo r b id ’s su b m is si o n , th e lo w e r th e c o st b o rn e b y fi rm s to p re p a re th e ir b id s. o u r d a ta sh o w th a t th e re is v a ri a b il it y in te rm s o f a u c ti o n s’ a d v e rt is e le a d ti m e , w it h a n a v e ra g e o f . d a y s (a n d a st a n d a rd d e v ia ti o n o f . d a y s) . in c o lu m n s ( ) a n d ( ), th e se c o n d a n d fi rs t st a g e o f a tw o -s te p h e ck m a n se le c ti o n m o d e l a re re p o rt e d . documents de travail du centre d'economie de la sorbonne - . t a b le d – l ea rn in g d y n a m ic s: fu rt h er re su lt s fo r a b a u ct io n s. d e p e n d e n t v a ri a b le lo g |d is ta n c e | a u c ti o n fo rm a t a b ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (p a s tp a r t) - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + p a s tp e r f ) - . * * * - . * * * . * . ( . ) ( . ) ( . ) ( . ) lo g ( + p a s tw in s ) - . - . . * * . * * ( . ) ( . ) ( . ) ( . ) lo g (b id d e r s o p h ) - . * * * - . * * * ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s f ir m c o n tr o ls y e s y e s y e s y e s n o n o n o n o f ir m -f e n o n o n o n o y e s y e s y e s y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , r -s q u a re d . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – l ea rn in g d y n a m ic s: re su lt s fo r a b l a u ct io n s. d e p e n d e n t v a ri a b le lo g |d is ta n c e | a u c ti o n fo rm a t a b l ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (p a s tp a r t) - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + p a s tp e r f ) - . * * * - . * * * - . - . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + p a s tw in s ) . * * . * * . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g (b id d e r s o p h ) - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s f ir m c o n tr o ls y e s y e s y e s y e s n o n o n o n o n o n o n o n o f ir m -f e n o n o n o n o y e s y e s y e s y e s n o n o n o n o f ir m -y e a r- f e n o n o n o n o n o n o n o n o y e s y e s y e s y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , , , , , r -s q u a re d . . . . . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – f u rt h er re su lt s: fi rm -c a te g o ry o f w o rk -fi x ed eff ec ts a n d fi rm -s em es te r fi x ed eff ec ts . d e p e n d e n t v a ri a b le lo g |d is ta n c e | a u c ti o n fo rm a t a b a b a b l a b l a b l a b l ( ) ( ) ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) - . * * * - . * * - . - . * * * - . * * * . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s f ir m -s e m e st e r- f e n o n o y e s n o n o n o f ir m -c a te g o ry o f w o rk -f e y e s n o n o y e s n o n o f ir m -c a te g o ry o f w o rk -s e m e st e r- f e n o y e s n o n o n o y e s f ir m -c a te g o ry o f w o rk -y e a r- f e n o n o n o n o y e s n o f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , r -s q u a re d . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk ,d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – s o p h is ti ca ti o n a n d b id le v el s: o v er a ll sa m p le . d e p e n d e n t v a ri a b le lo g (d is c o u n t) d is c o u n t lo g (d is c o u n t) d is c o u n t lo g (d is c o u n t) d is c o u n t lo g (d is c o u n t) d is c o u n t a u c ti o n fo rm a t a b a b a b a b a b l a b l a b l a b l ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) . . - . - . * - . - . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s f ir m -f e y e s y e s n o n o y e s y e s n o n o f ir m -y e a r- f e n o n o y e s y e s n o n o y e s y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , r -s q u a re d . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk ,d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – s o p h is ti ca ti o n a n d b id le v el s: q u a n ti le re g re ss io n s. q u a n ti le (t h ) a u c ti o n fo rm a t a b d e p e n d e n t lo g (d is c o u n t) lo g (b id d e r s o p h ) . * * * . * * * . * * * . * * * . * * * . * . . - . - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) d e p e n d e n t d is c o u n t lo g (b id d e r s o p h ) . * * * . * * * . * * * . * * * . * * * . * * . . - . - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) o b se rv a ti o n s , , , , , , , , , , , a u c ti o n fo rm a t a b l d e p e n d e n t lo g (d is c o u n t) lo g (b id d e r s o p h ) . * * * . * * * . * * * . * * * . . - . - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) d e p e n d e n t d is c o u n t lo g (b id d e r s o p h ) . * * * . * * * . * * * . * * * . . - . - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) o b se rv a ti o n s , , , , , , , , , , , a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s f ir m c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s y e s r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk ,d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – c o n tr o ll in g fo r p o te n ti a l ca rt el s in a b a u ct io n s. d e p e n d e n t lo g |d is ta n c e | a u c ti o n fo rm a t a b ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + g r o u p m e m b e r s ) - . * * * . - . * * * - . - . * * * - . * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + g r o u p m e m b e r s ) x s h a r e g r o u p m e m b e r s - . * * * - . * * * - . ( . ) ( . ) ( . ) s h a r e g r o u p m e m b e r s . . * * . ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s f ir m c o n tr o ls y e s y e s n o n o n o n o y e s n o f ir m -f e n o n o y e s y e s n o n o n o y e s f ir m -y e a r- f e n o n o n o n o y e s y e s n o n o f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , , , r -s q u a re d . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk ,d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – c o n tr o ll in g fo r p o te n ti a l ca rt el s in a b l a u ct io n s. d e p e n d e n t lo g |d is ta n c e | a u c ti o n fo rm a t a b l ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + g r o u p m e m b e r s ) . . * * - . . - . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) lo g ( + g r o u p m e m b e r s ) x s h a r e g r o u p m e m b e r s - . * * - . - . ( . ) ( . ) ( . ) s h a r e g r o u p m e m b e r s . . . ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s f ir m c o n tr o ls y e s y e s n o n o n o n o y e s n o n o f ir m -f e n o n o y e s y e s n o n o n o y e s n o f ir m -y e a r- f e n o n o n o n o y e s y e s n o n o y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s y e s y e s y e s y e s y e s o b se rv a ti o n s , , , , , , r -s q u a re d . . . . . . . . . o l s e st im a ti o n s. r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk ,d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – f u rt h er s l s es ti m a ti o n s d e p e n d e n t v a ri a b le lo g (b id d e r s o p h ) (b id d e r s o p h ) |d is ta n c e | |d is ta n c e | a u c ti o n fo rm a t a b + a b l a b + a b l a b + a b l a b + a b l ’s ta g e ’s ta g e ’s ta g e ’s ta g e ( ) ( ) ( ) ( ) lo g (b id d e r s o p h ) - . * * * - . * * * ( . ) ( . ) a b l - . * * * - . * * * ( . ) ( . ) lo g (b id d e r s o p h − ) . * * * ( . ) a b l ∗ lo g (b id d e r s o p h − ) - . * * * - . * * * ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s f ir m c o n tr o ls y e s n o y e s n o f ir m -fi x e d e ff e c ts n o y e s n o y e s f ir m -a u c ti o n c o n tr o ls y e s y e s y e s y e s o b se rv a ti o n s , , , , r -s q u a re d . . . . h a n se n -j te st . . r o b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e ty p e o f w o rk . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m - a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . documents de travail du centre d'economie de la sorbonne - . t a b le d – a d d it io n a l em p ir ic a l ed v id en ce . d e p e n d e n t v a ri a b le : n o r m a li z e d n o r m a li z e d a a a u c ti o n a u c ti o n f ir m f ir m f ir m f ir m d is c o u n t d is c o u n t s t. d e v . s t. d e v . s t. d e v . s t. d e v . s t. d e v . s t. d e v . a u c ti o n fo rm a t a b + a b l a b + a b l a b a b l a b a b l a b a b l a b a b l ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) a b l - . * * * - . * * * ( . ) ( . ) lo g (n o .p a r ti c ip a n ts ) . * * - . * * ( . ) ( . ) lo g (m e a n b id d e r s o p h ) - . * - . * * ( . ) ( . ) lo g (r o ll in g m e a n b id d e r s o p h ) - . * * * - . * * * - . * * * - . * * * ( . ) ( . ) ( . ) ( . ) a u c ti o n / p ro je c t c o n tr o ls y e s y e s y e s y e s y e s y e s n o n o n o n o f ir m c o n tr o ls y e s n o n o n o n o n o y e s y e s n o n o f ir m -fi x e d e ff e c ts n o y e s n o n o n o n o n o n o y e s y e s f ir m -a u c ti o n c o n tr o ls y e s y e s n o n o n o n o n o n o n o n o o b se rv a ti o n s , , , , r -s q u a re d . . . . . . . . . . in c o lu m n s ( )- ( ) a n d ( )- ( ): o l s e st im a ti o n s a n d ro b u st st a n d a rd e rr o rs c lu st e re d a t fi rm -l e v e l in p a re n th e se s. in c o lu m n s ( )- ( ), a n ir l s e st im a to r is u se d to a c c o u n t fo r th e in fl u e n c e o f o u tl ie rs (g iv e n th e sm a ll sa m p le s) . in fe re n c e : (* * * ) = p < . , (* * ) = p < . , (* ) = p < . . in c o lu m n s ( ) a n d ( ), th e d e p e n d e n t v a ri a b le is th e (m in -m a x re sc a le d ) d is c o u n t o ff e re d b y fi rm s. a b l is a d u m m y v a ri a b le w h ic h ta k e s v a lu e ( ) if th e a u c ti o n is a b l (a b ). t h o u g h n o t re p o rt e d , th e so p h is ti c a ti o n in d e x is in c lu d e d a m o n g th e c o v a ri a te s. in c o lu m n s ( ) a n d ( ) th e d e p e n d e n t v a ri a b le is th e (a u c ti o n -s p e c ifi c ) re fe re n c e p o in t. in c o lu m n s ( ) a n d ( ) th e d e p e n d e n t v a ri a b le s d a u c ti o n is th e st a n d a rd d e v ia ti o n o f th e (a b so lu te v a lu e o f th e st a n d a rd iz e d ) d is ta n c e o f b id s fr o m th e re fe re n c e p o in t. in c o lu m n s ( ) a n d ( ) th e d e p e n d e n t v a ri a b le r o ll in g s d f ir m is th e ro ll in g st a n d a rd d e v ia ti o n o f th e (a b so lu te v a lu e o f th e st a n d a rd iz e d ) d is ta n c e o f b id s fr o m th e re fe re n c e p o in t in th e la st fi v e a u c ti o n s. m e a n b id d e r s o p h is th e a v e ra g e o f th e so p h is ti c a ti o n in d e x a c ro ss fi rm s in th e a u c ti o n . r o ll in g m e a n b id d e r s o p h is th e ro ll in g a v e ra g e o f th e so p h is ti c a ti o n in d e x o f th e fi rm in th e la st fi v e a u c ti o n s. a u c ti o n / p ro je c t co n tr o ls in c lu d e : th e a u c ti o n ’s re se rv e p ri c e , th e e x p e c te d d u ra ti o n o f th e w o rk , d u m m y v a ri a b le s fo r th e ty p e o f w o rk , d u m m y v a ri a b le s fo r th e y e a r o f th e a u c ti o n . f ir m co n tr o ls in c lu d e : d u m m y v a ri a b le s fo r th e si z e o f th e fi rm , a n d th e d is ta n c e b e tw e e n th e fi rm a n d th e c a . f ir m -a u c ti o n co n tr o ls in c lu d e : a d u m m y v a ri a b le fo r th e fi rm ’s su b c o n tr a c ti n g p o si ti o n (m a n d a to ry o r o p ti o n a l) , a n d a m e a su re o f th e fi rm ’s b a ck lo g . in c o lu m n s ( )- ( ) ti m e d u m m ie s ta k in g th e v a lu e fo r th e m e a n y e a r o f th e b id d e rs ’ la st fi v e a u c ti o n s a re in c lu d e d . documents de travail du centre d'economie de la sorbonne - . introduction auction formats and descriptive evidence theory: equilibrium vs. cognitive hierarchy empirical analysis a measure of firms' sophistication estimated equation description of the sample main estimation result learning dynamics discussion strategic ability vs. competitiveness potential collusion instrumental variables further evidence conclusion proof of proposition proof of proposition numerical simulations additional empirical evidence http://fty.sagepub.com feminist theory doi: . / ; ; feminist theory ruth holliday and jacqueline sanchez taylor aesthetic surgery as false beauty http://fty.sagepub.com/cgi/content/abstract/ / / the online version of this article can be found at: published by: http://www.sagepublications.com can be found at:feminist theory additional services and information for http://fty.sagepub.com/cgi/alerts email alerts: http://fty.sagepub.com/subscriptions subscriptions: http://www.sagepub.com/journalsreprints.navreprints: http://www.sagepub.co.uk/journalspermissions.navpermissions: http://fty.sagepub.com/cgi/content/refs/ / / citations at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com/cgi/alerts http://fty.sagepub.com/subscriptions http://www.sagepub.com/journalsreprints.nav http://www.sagepub.co.uk/journalspermissions.nav http://fty.sagepub.com/cgi/content/refs/ / / http://fty.sagepub.com aesthetic surgery as false beauty tf ruth holliday and jacqueline sanchez taylor university of leeds feminist theory copyright © sage publications (london, thousand oaks, ca and new delhi) vol. ( ): – . – doi: . / http://fty.sagepub.com abstract this article identifies a prevalent strand of feminist writing on beauty and aesthetic surgery and explores some of the contradictions and inconsistencies inscribed within it. in particular, we concentrate on three central feminist claims: that living in a misogynist culture produces aesthetic surgery as an issue predominantly concerning women; that pain – both physical and psychic – is a central conceptual frame through which aesthetic surgery should be viewed; and that aesthetic surgery is inherently a normalizing technology. engaging with these ‘myths’, we explore the tensions uncovered through a historical analysis of the practices of aesthetic surgery as well as the challenges to feminist claims offered by post-feminism. in particular we seek to destabilize the connection in feminist writing between beauty and passivity. we argue that through aesthetic references to denigrated black and working-class bodies, young women may mobilize aesthetic surgeries to reinscribe active sexuality on the feminine body. keywords aesthetic surgery, beauty, body, class, race in this article we aim to disrupt some of the usual ways in which feminists have come to think about the female (and male) body, in order to find a space between the prevalent discourses for some alternative explanations. our principal aim is to explore some of the diverse reasons why women (and men) may engage in aesthetic surgery, without relying on the beauty myth as a determining argument. instead we focus on seekers of aesthetic surgery as either consumers (exercising choice within a given set of constraints) or as reflexively engaged in a project of the self (within a limited range of possible selves). we aim to widen understandings of aesthetic bodily practices to extend beyond gender and/or ‘race’ in any conventional sense. furthermore, we aim to decouple the link between beauty and passivity, or at least to decentre it, by positing alternative corre- lations such as the link between glamour and active sexuality. in doing this we will also uncover some of the ways in which feminist discourses of beauty are inherently classed and ‘raced’. however, moving away from a singular explanation – beauty, normalization, internalized racism, for instance – inevitably complicates our argument. in the following sections at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com we consider gender, ‘race’ and class; work, consumption and emulation; feminism and post-feminism; as well as the interaction and interrelation between these frequently intertwined categories. a beautiful history theories of beauty have a very long history. what makes something or someone beautiful, whether beauty is a property of the object/person or rather rests in the eye of the beholder, and whether or not a consensus exists on what exactly is beautiful, are questions that have occupied thinkers since the ancient greeks. feminists, however, have tended to skip such fundamental questions, drawing rather on the view that beauty is part of the currency of power. feminists have asked not what beauty is, but who is in charge of the standards and definitions of beauty and what their motives are for maintaining them. they have also drawn on existential philosophy (offered via de beauvoir) in order to identify the consequences of being defined as a beautiful woman, and on foucauldian theory to demonstrate the technologies at work in becoming beautiful (bordo, ; bartky, ). we do not intend to propose an alternative definition of beauty; in any case beauty always exceeds the rule that defines it. rather, we want to re-examine some early theorizations and practices of beauty in order to demonstrate their considerable influence on later thinking, and on feminist thought. we aim to expose some fundamental contradictions that structure contemporary notions of beauty. the first thinker to consider beauty in any sustained and analytical way, perhaps, was plato ( ). for plato our world is a world only of partial representations of another one – the realm of forms. our immortal souls lived in the realm of forms before our life in this world, and we are reminded of it but can never fully recall it whilst in this life. in the symposium socrates argues that beauty is what attracts us, and that the good is the one thing that can be attractive above all else and that makes beautiful things beautiful. worldly instances of anything – such as a beauti- ful thing – should lead us to seek the beautiful itself, the form of beauty. all experienced examples of a form thus recall the form itself; beautiful things lead us toward the beautiful, and the beautiful is beautiful because it is what is loved, and we can only love the good. plato used the term callos both to denote beauty as it is experienced through the five senses and to denote that which is morally noble. thus, for platonists, beauty always has a moral quality. when we see a beautiful person, that percep- tion jolts our memory of this former realm and gives rise to feelings of love for that person; plato uses the metaphor of growing wings and trying to fly back to the heavenly realm of forms. beauty, love and moral goodness are thus inextricably linked, and also connected to truth and knowledge. however, we should remember that plato was, of course, talking about beautiful men, not women. seeing a beautiful boy could inspire a philos- opher towards greater pursuit of the forms of truth and knowledge. women were seen as less capable of attaining a state of pure contemplation or communion with the soul. since the beauty of boys is linked to pedagogy, feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com the boy could be a loved/beautiful object in a relation that would lead to learning and mastery. women were outside this pedagogic relation. the beauty of a woman is thus fundamentally different from the beauty of a man. plato was highly influenced by pythagoras and saw a connection between geometry and beauty. the perfect form is symmetrical and follows strict numerical proportions. perfect proportion, which could be mathe- matically proven, was also seen as a door into the realm of forms, a bridge to the other world. aristotle shared this respect for numbers and symmetry, but rather than these acting as a reminder of or door to another realm, for aristotle these were characteristics firmly rooted in this world. for aris- totle, beauty is related to how well an object is designed to be able to meet its function or goal. beauty is order, symmetry and definiteness. for aristotle, beauty is rooted in the real world, and has a purpose. (for human beings this might mean that beauty leads to reproduction, for example [aristotle, ].) another important step to outline is the ways in which these ideas were taken up in early christianity. early ecclesiastical scholars thomas aquinas and augustine worked to reconcile platonism and christianity. like plato, these scholars saw beauty as a reminder of another world – heaven. through gazing on beauty we progress from ‘sensible beauty’ up a ladder of love to the beautiful revelation of god. god is the arch designer and makes man, perfectly proportioned, in his own image. thus a beauti- ful man reminds us of god, but a beautiful woman is problematic, since she is not made in god’s image, so her beauty is much more ambiguously conceived (synnott, ). later thinkers expanded on the already established link between beauty and measurement. beauty, they thought, was a scientifically measurable phenomenon related to perfect proportion. this position is perhaps best illustrated through the work of leonardo da vinci (and many of his contemporaries) and is most evident in his vitruvian man whose propor- tions are painstakingly measured out. however well intentioned, it is but a short step from vitruvious to the head measurements associated with scientific racism (blumenbach, ( ); ripley, ; goldberg, ). thus early theorizations of beauty have been used to exclude many people from white western standards of beauty. alongside this connection between (white) men’s beauty, morality, spirituality, truth and knowledge, there also exists another narrative – of women’s beauty, which is most usually suspect. women’s beauty is more often linked to deception than to truth or goodness. for plato, for example, true (men’s) beauty is original, close to the forms from which sensible and bodily experience is derived, closer to the very order and proportion of the world; whereas women’s beauty is connected with adornment and simulation – women also being at one remove from the human form that is god’s image. in many religious texts women’s beauty causes man’s fall from faith, truth, knowledge and goodness. beauty corrupts, and beauty itself can be faked. in the old testament every refer- ence to the application of make-up relates to a ‘bad’ woman, jezebel being holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com the best known. in almost every instance these decorated women are also egyptian, or ‘other’ women. women who paint their faces usually do so for seduction – using sexuality to confuse men, usually with some ulterior motive in mind. women using make-up are thus bad women, as opposed to unpainted good women. so naturally beautiful women are good, falsely beautiful made-up women are bad – bad because they have a sexuality. naturally beautiful women submit to and carry out the will of others – their father, husband, brothers, gods. falsely beautiful women use their beauty for their own ends, to manipulate men. thus, we are left with a startlingly different formulation to that proposed by many feminists: naturalness = passivity, false beauty = agency. for men, then, beauty is good because it is connected to truth, knowledge and spirituality. for women, natural beauty is good because it is passive; false or ‘enhanced’ beauty is bad because it reflects the active (sinful) intentions of the woman herself. grotesque bodies? having briefly outlined the theoretical origins of the classical body we will now explore its ‘opposite’ – the grotesque body. this is especially import- ant since contemporary western culture continues to make links between these different bodies, the beautiful and the grotesque. the grotesque body is most strongly associated with mikhail bakhtin’s ( ) work on the medieval carnival in europe. bakhtin argued that carnivals celebrated the unfinished body – a body that was intimately connected with, and open to, the world around it. the grotesque body was celebrated by working people in an irreverent critique of the classical body, itself linked to self- discipline, spirituality and thus the aristocracy. two bodies came to represent two coexistent cultures – the classical stood for the officially sanctioned (serious) culture, and the grotesque represented the unofficial (playful and largely lost) culture of ‘the people’. classical bodies were characterized by grooming, beauty and grace. the grotesque body empha- sized and exaggerated the mouth, anus, buttocks, penis, belly, breasts, nose, eyes and ears, to demonstrate the body’s unboundedness. for bakhtin, the grotesque body was part of a culture of fun, not revered like the classical body, but sent up in a collective humour that always recognized the reveller as part of the joke: making the grotesque the object of laughter, one implicitly laughed at oneself. the grotesque was never beautiful, but working people felt an affinity with and affection for it. however, the developing cultural authority of the bourgeoisie by the th and th centuries sought to erase the carnivalesque and all its associations (stallybrass and white, ). the controlled body came to take a pivotal role for the bourgeoisie in defining ‘respectable’ citizenship with all the benefits that accrued to that category, and oppositions between the classical and the grotesque became integral to concepts of class, gender, ‘race’ and sex. by the end of the th century in europe and its colonies, the only proper, respectable body was a controlled, slender and ‘unmarked’ one. those bodies unable to escape the struggles of everyday survival, a feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com life so celebrated in carnivalesque imagery, began to be marked pejoratively as grotesque and hence denigrated. ‘other’ ‘races’, genders, sexualities, classes and ages began to be system- atically incorporated into a sophisticated binary system that attributed relative value and differing moral characteristics to different types of bodies, and the grotesque body became increasingly central to the burgeon- ing ‘science of the other’ (stallybrass and white, ). the ‘science’ of ‘race’ conflated white with rationality, goodness and purity, and black with degeneration, dirt and danger (mcclintock, ). these systems combined with social darwinism to form what has been called the ‘racial- ization’ of gender, sexuality and class through the insistence on essential signifiers of biological degeneracy in all these categories (gilman, ). the belief that there was an intrinsic biological basis for human behav- iour and difference underpinned much of enlightenment thinking. black bodies were considered closer to nature (negatively in this formulation) and particularly invested with uncontrollable sexuality and a lack of morality. science was deployed to ‘prove’ this sexual degeneracy through, for instance, the measurement of hips and buttocks (krafft-ebing, ). nowhere was this idea made more explicit than in the exhibition through- out europe in the th century of sara baartman, known as the ‘hottentot venus’, whose protruding buttocks (and therefore grotesque body) were taken to signify the truth of her arrested development and voracious sexuality (gilman, ). middle-class white women, however, were stripped of sexual desire and placed in opposition to the hypersexual black woman, whilst nevertheless being considered incapable of rational thought. it is easy to see, then, why a largely white, middle-class feminism has until recently tended towards favouring a desexualization of the body in favour of claims to rational thought and moral superiority. the body therefore became a marker of who is valued and who is denigrated, who is included and excluded in civil society, and the particu- lar racialized, gendered, classed and age traits of each body were assumed to express the social position, intellectual ability, or sexual characteristics of the person in question. bodies were thus carefully managed in order to be read as appropriate for social contact. dress is one mechanism for achieving this aim (goffman, ), but increasingly aesthetic surgery is being used to enhance people’s chances of participation in the public sphere, especially through enacting social mobility. the feminist body feminist work has frequently engaged with traditional political and social theory, itself concerned with developing the idea of a sovereign subject that can enter into contracts based on equality. equality, though, is not just a right but something that has to be demonstrated. equality depends on the ability to engage rationally – in particular by putting aside those more visceral influences that are said to cloud rationality. simone de beauvoir’s ( ) profoundly influential writing, for example, starts from this assump- tion. women, she says, are twinned with nature and their bodies, men with holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com culture and their minds; women with immanence and men with transcen- dence. women can never be accepted as fully rational because they are seen as governed by their hormones – their reproductive potential marking them as animalistic (and implicitly sexual) (see for instance, grosz, and shildrick, who develop this point). this absence of rationality marks women as objects, never fully self-present, and engaged in constant self-scrutiny. according to de beauvoir, this results in women’s reduction to, and constant and trivial obsession with, their bodies and beauty. to gain equality with men, then, feminists must reject those qualities that mark them as different – as women. women should seek to transcend their bodies and therefore reject beauty. immanence is also, of course, a quality of other ‘others’ who are neither defined as, nor required to be, beautiful. working-class and black women have more frequently been denied the ‘luxury’ of beauty, and instead have been concerned with earning their living in dirty and sometimes danger- ous conditions. however, despite being thought of as ugly, they have, at the same time, been invested with ‘a hypersexuality’ (mcclintock, ). thus, ‘true’ beauty has been desexualized, bringing respectability for white, middle-class women through their distance from ‘other’ sexualized women. while beauty may have been experienced as a constraint for middle-class women, for ‘other’ women achieving beauty meant attaining the ‘respectability’ that signified enhanced status. by the s, the ‘black is beautiful’ movement – one which sought to expand definitions of beauty to include black women (and men) – offered an important political voice, given the benefits associated with beauty in a ‘host’ or colonizing culture (tate, ). reproducing the body image of white, middle-class women has also been highly desirable for working-class women (skeggs, ). thus access to a system that equates beauty with value has been central for both black and working-class women, women whom feminism, in adopting an anti-beauty position, therefore excludes. much second-wave feminist attention turned to the problem of the objec- tification of women (although there was more than one way of articulating this argument within the second wave [cf. hemmings, ]). in particu- lar, women’s bodies were often constructed as being objectified and passively consumed by the active male gaze. this argument has found its greatest intensity in anti-pornography arguments (mackinnon, ) but also in film studies; as mulvey ( ) puts it, men look (where looking is active) and women display ‘to-be-looked-at-ness’ (where being looked at is always passive). other feminist criticisms of beauty concern the narrow- ness and exclusiveness of its definition; the commodification of beauty (both in terms of the products required to achieve it and its commercial value in industries such as pornography, glamour, fashion and sales); and the labour required to maintain a beautiful body and the time/money costs of this to women themselves (dworkin, ; bartky, ; wolf, ; bordo, ; adkins, ; mackinnon, ; black, ; jeffreys, ). the feminist intellectual ethic, then, has tended to reject the value associated with the beautiful body. feminist politics concentrated on erasing the markers of beauty-as-labour from the body, because concern feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com with beauty has come to signify women’s social oppression. instead, in striving for transcendence, feminists have come to celebrate the ‘natural’ body: beauty is associated with decoration and adornment, and the natural body strips these accoutrements away. but this aesthetic too frequently conceals its operations – looking natural is not the same as being natural, and similar bodily regimes are often viewed in different ways. going to the gym becomes about health, fitness and energy levels, for example, rather than slenderness and beauty; dieting is reframed as ‘eating sensibly’ or making sure clothes still fit. however, this rejection by feminism of the enhanced body may be overly dependent on the norms of naturalness and origin that were once used to condemn women’s beauty as a simulation. the feminist acceptance of only a naturally beautiful body in fact endorses certain modes of cultivation – such as the gym – while arbitrarily dismiss- ing others, such as the beauty industry, interpreting the former as active and chosen and the latter as passive and consumed. gender and the knife feminists working on aesthetic surgery have identified a variety of differ- ent motives for women undertaking procedures. the ‘voices’ and subjec- tive experiences of patients can support a wide range of different theoretical positions. thus, whilst feminist writers tend to disagree on issues such as whether women strive to achieve beautiful bodies (bordo) or ‘normal’ bodies (davis), there seems to be agreement on several basic themes. the first is that, since aesthetic surgery exists within a misogynis- tic culture, it will only ever really be an issue that affects women, some- times incorporating a small proportion of deviant (feminized) men. kathy davis ( ), for instance, argues that men will never be aesthetic surgery patients in significant numbers since the whole construction of being a patient or surgeon is intrinsically gendered. she underpins this argument with current statistics on men’s surgery, but in order to justify her claim fully she first excludes hair transplant operations and then states that in the us just per cent of all aesthetic surgery operations are carried out on men (davis, : ). morgan ( : ) produces a higher figure of male clients, estimating that – per cent of procedures are carried out on men, yet she still omits men from her discussion. in fact aesthetic surgery has been practised for millennia, in various ‘misogynistic cultures’, and at times the majority of its patients have been men (probably because only men could afford it) (taschen, ). the ‘nose job’, for instance, has its origins in disguising the syphilitic body. gaspare tagliacozi ( – ) introduced flap graft procedures, using skin from the arm to reconstruct the nose, into early modern european surgery. his procedure was revised a century and a half later using a connected skin graft from the forehead and cheeks. in carl ferdinand von graefe published a book on the reconstruction of the nose and estab- lished rhinoplasty as the name for the procedure, giving it a classical name like other surgeries (gilman, ). however, the greatest surgeon of antiquity, claudius galen (ad c. –c. ), was perhaps the founder of holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com aesthetic surgery. he was well known for the surgical reconstruction of gladitorial wounds, and his expertise also extended to the correction of drooping eyelids as well as the removal of fatty deposits from men’s breasts. such operations were performed on wealthy and powerful men in an era when men embodied true beauty, and perfection of the body was considered an art form. it is also rumoured that the roman emperor, elagabalus (ad – ), a young successor to marcus aurelius and a trans- vestite, became the first man in history to undergo a sex change operation. but there is a form of aesthetic surgery that is older still, one so routine that it passes even without note – circumcision. an average of per cent of american infant boys are currently circum- cised with the figure rising to over per cent in the midwest (gollaher, ). circumcision was first practised on aristocratic young men among the ancient egyptians and recorded on some of the earliest known stone carvings. within judaism and islam, circumcision is practised for symbolic rather than medical reasons – as a sign of the covenant and in order to attract god’s divine light. circumcision, it is believed, enhances the body and thereby cleanses the mind, ostensibly by reducing sexual pleasure such that a man might turn his attention away from sex (and women in particular) and towards god. moreover, during the greek ascendancy men performed sports in the nude. however, since sport was about personal and spiritual development it was imperative that men did not display an erection. the circumcised penis displays a greater likeness to an erect one than the uncircumcised penis, and thus many jewish men who wished to compete in sporting events sought surgical (and other) methods to reverse their circumcisions. circumcision is in fact key to the development of aesthetic surgery, and therefore so is the male patient and so is ‘race’. what distinguishes these masculine practices from contemporary feminine ones is not the extent of the surgeries but rather the value attributed to them. making the body beautiful was an ‘art’, an act of aesthetic creation for men amongst the ancients; it is now something feminized, superficial and trivial – cosmetic. the term cosmetic has a number of connotations. first, to say that some- thing is cosmetic means that it is superficial, trivial (it is only cosmetic). second, cosmetic means surface, not depth (only skin deep). in a culture that views the body as a medium of expression, as the outward represen- tation of the inner self (see dollimore, ), the cosmetic is problematic. divorced from its potential as outward signifier of inner signified, the cosmetic is also duplicitous: it mis-represents. so cosmetic (fake) beauty is problematic. it is no coincidence, then, that masculine art, in its attempt to capture true beauty, chooses the unadorned female nude as its muse (davis, ). a second central point in the feminist aesthetic surgery literature is the issue of pain – both physical and psychic. take the following quotation by kathryn pauly morgan: we need a feminist analysis to understand why actual, live women . . . choose to participate in anatomising and fetishizing their bodies as they buy ‘contoured feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com bodies’, ‘restored youth’, and ‘permanent beauty’. in the face of a growing market and demand for surgical interventions in women’s bodies that can and do result in infection, bleeding, embolisms, pulmonary edema, facial nerve injury, unfavourable scar formation, skin loss, blindness, crippling, and death, our silence becomes a culpable one. ( : ) however, we should be wary of an approach that foregrounds pain and risk as an argument per se against a surgical practice informed by choice rather than medical necessity. by the same logic we would take a stand against abortion, for example. in the same article morgan compares her work on aesthetic surgery with bordo’s work on anorexia, but she leaves it to a footnote to add one significant difference: . . . although submitting to the procedures of cosmetic surgery involves [short- term] pain, risks, undesirable side effects, and living with a heightened form of patriarchal anxiety, it is also fairly clear that . . . the outcome often appears to be one that greatly enhances the women’s confidence, confers a sense of wellbeing, contributes to a greater comfortableness in the public domain, and affirms the individual woman as a self-determining and risk-taking individual. (p. ) morgan also criticizes intervention in childbirth as a masculinist appropri- ation of women’s bodies and fertility. feminists in this camp (see wajcman, for a full discussion) have a tendency to present ‘natural’ childbirth as something that women ought to be striving for, and worth the small risk of being away from a hospital environment. pain, according to this argument, is good, since women can be fully present during their births as well as experiencing a ‘rite of passage’ into full womanhood. similarly, feminists writing on body modification tend to view pain and risk as an essential part of reclamation rituals (such as tattooing, piercing, scarifica- tion or branding). pain here is a cure for psychic distress brought about by earlier violations of the body (pitts, ). such studies tend to point to the transgressive potential of both pain and body modifications in ‘anti- beauty’ movements. kathy davis ( ) has also focused on the issue of pain, but her interest centres on the psychic pain experienced by those who feel deep psycho- logical anxiety about their size or shape or what they perceive to be ‘defects’ in their bodies. davis argues that whilst feminists have focused on aesthetic surgery as part of the pursuit of beauty, the women in her study simply wanted to be ‘normal’. in the netherlands and the uk, surgery for women experiencing psychological pain is often free and fully sanctioned by the medical establishment, especially when it is seen as repair of ‘defective’ bodies. this is referred to as ‘plastic surgery’, whereas surgery for the purposes of ‘enhancement’ is labelled ‘cosmetic surgery’ and tends to be conducted through private practice. the latter also tends to be trivialized by the medical establishment as pandering to the whims of rich, vain women. because davis focuses on free surgery, she refutes the idea that women are in pursuit of beauty, and instead maintains that women simply want to be ‘normal’. in the process she fails to address two important issues. holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com first, her refusal of beauty simply seems to reaffirm it as trivial and vain, thus denying its importance to women in enhancing status, economic reward and thus citizenship. second, since the women she interviewed are seeking free aesthetic surgery from the state, it seems likely that they will express their desires in terms of pain, since it is pain that qualifies them for free surgery. this same practice is identified by sandy stone ( ) in her critique of the medicalized definition of transsexualism: only those purporting to be in the ‘wrong body’ and experiencing considerable psychic discomfort are rewarded with medical diagnosis and free surgery. however, judith butler ( ) cautions against a ‘strategic’ approach to surgery, since one exercises the right to (free) surgery only by submitting to a pathologizing discourse, by relinquishing the right to define one’s self truthfully in one’s own words. choice, she says, ‘is clearly bought at a price, sometimes at the price of truth itself’ (p. ). a third position advanced by feminists is that aesthetic surgery inher- ently produces normalized bodies. morgan argues that aesthetic surgery is itself becoming routine, and that this shift is: leading to a predictable inversion of the domains of the deviant and the patho- logical, so that women who contemplate not using cosmetic surgery will increas- ingly be stigmatised and seen as deviant. ( : , emphasis in original) davis argues that given the desire to normalize (as in the case of her respon- dents), the private health care sector generates a potentially unlimited market for surgery, each of its clients seeking the same body. davis’s main concern is that ‘one ideal – a white, western model – becomes the norm to which everyone, explicitly or implicitly, aspires’ ( : ). consump- tion is thus equated with sameness. she is also worried that ‘anyone’ might become a candidate for surgery, since no one is ‘normal’, and that surgery might become a matter of ‘choice’ rather than ‘need’. in highlighting pain in her own research, she effectively argues that women are not ‘selfish’ consumers of beauty but ‘victims’ of its ubiquitous discourses. here we see a repetition of the structure–agency dichotomy, where those who consider themselves ‘agents’ are characterized as misguided, apolitical and selfish, whilst those that admit to being victims are considered deserving of surgery. however, for bordo, even those characterizing their actions as choices are ultimately only ever victims of the beauty industry: . . . the rhetoric of choice and self-determination and the breezy analogies comparing cosmetic surgery to fashion accessorizing are deeply mystifying. they efface not only the inequalities of privilege, money, and time that prohibit most people from indulging in these practices, but also the desperation that characterizes the lives of those who do. ( : ) on the contrary, contemporary consumption is frequently as much about differentiation and distinction as it is about normalization (corrigan, ). aesthetic surgery through private practice circumvents medical diagnosis so the range of possible surgeries available (to those who can afford it) is considerably expanded. we might argue, then, that aesthetic surgery to reduce psychological pain is likely to produce a normalized body, whilst feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com surgery as consumption might instead produce a proliferation of difference. this idea is supported by recent ‘ideal bodies’ represented in popular magazines that foreground racial ‘mixing’ – jlo’s bottom, halle berry’s breasts, cindy crawford’s legs and so on (heat, november ). but as well as ‘normative’ aesthetic surgeries like facelifts (young person trapped in an old person’s body), we can also consider the number of ‘non- normative’ surgeries that are increasingly taking place – transsexual surgery (woman trapped in a man’s body), operations to make the patient look more like a tiger (tiger trapped in a man’s body), amputations (disabled person trapped in an able-bodied person’s body), as well as breast implants in men or shaped collarbone implants adding interest to any body. feminists are therefore failing to give proper critical attention to the prevalent discourse of cosmetic surgeons and patients themselves, which is one of ‘enhancement’. enhancement does not suggest the transformation of the body, rather it suggests a working ‘with’ the body that a patient already has. a fairly typical example of the sales rationale of these clinics is provided by beaucare: nowadays appearance matters more and more. if you also want to experience that beautiful feeling, clinic beaucare will be something for you. we consider quality of paramount importance. cosmetic surgery is an art. to strive for perfec- tion and to make beautiful is the plastic surgeon’s most important goal. we make you feel on top of the world, by meeting your wishes in a medically justified way and by giving you just that little bit more. (clinic beaucare, ) the discourse of this clinic is framed in terms of self-improvement rather than psychic distress – the quest for perfection which can ‘make you feel on top of the world’. the aim of ‘giving you just that little bit more’ suggests the (self) improvement of the existing body – its enhancement – rather than the promise of a different body. in opposing the surgically modified body to the natural body feminists are in danger of essentializing gender, ‘race’ and ability (see jeffreys, ), as well as reproducing ancient masculinist discourses of feminine beauty. and, by pointing to the physical pain and side effects that surgery entails, feminists simply rehearse a familiar discourse, readily available in the media in shows such as cosmetic surgery from hell, and do little to advance its understandings. these argu- ments become equally problematic when we examine how discourses around ‘race’, class and work intersect with aesthetic surgery. reclaiming (fake) beauty? recently, post-feminists have claimed that feminists have lost their credibility with younger women by presenting them as perpetual victims of patriarchal control (roiphe, ; denfield, ). although this critique has tended to oversimplify feminist debates, post-feminism has problematized victimhood and foregrounded women’s autonomy, responsibility and agency. how women dress has become a key area of holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com conflict. sarah gamble ( : ) describes post-feminism as ‘women dressing like bimbos, yet claiming male privileges and attitudes’. implicit in this position is an assumed correlation between ‘dressing like a bimbo’ and ‘dressing for men’. but as far back as elizabeth wilson was disputing the idea that sexually suggestive attire and adornment was aimed at attracting men: the belief that [women dress for men] has confirmed many fashion writers in their view of women as essentially silly, since they have seldom questioned the idea that it is every woman’s chief preoccupation to arouse male desire . . . [fashion] is interpreted as sexual rivalry – for a woman to dress ‘for other women’ means simply in order to compete. (wilson, : ) in europe, and to a lesser extent in the us (where abercrombie and fitch clothing catalogues are given out in brown paper bags in some states), high- street fashions have tended towards cropped and low-cut tops and low- waisted trousers that reveal the female body in highly suggestive ways. items of clothing that were taken by feminists to symbolize women’s oppression such as high-heeled shoes and corsets have been reclaimed and imbued with ‘new’ meaning. these trends have reinscribed female sexuality as potentially powerful. as angela mcrobbie explains: in the climate of ‘popular feminism’ when women are more likely to recognise the unfairness of traditional male attitudes to girls who are ‘easy’ the chances are that young women will feel more free to have sex. ( : ) but post-feminism, even in its most popular forms, should not be taken as a reaction against feminism. in fact post-feminism is aware of, and draws on, some of feminism’s most significant struggles. the major difference between feminism and post-feminism is one of attitude rather than substantive political issues. post-feminism foregrounds agency: it recog- nizes the unfairness of gender relations and seeks actively to redress them. since feminism is identified with women’s lack of autonomy as well as a de-emphasizing of women’s sexuality, post-feminism conflates these issues into an alternative formulation – sexual assertiveness signifies power and autonomy. thus, in the new millennium, active, even ‘aggressive’ sexuality, performed through the wearing of revealing clothing, connotes power, autonomy, individuality and success for (especially young) women. what, though, are we to make of the more recent trend towards women who actively ‘enhance’ their breasts, buttocks and lips through surgery? and importantly, how have feminists conceptualized these tendencies? traditionally the hypersexed body – most usually classed and ‘raced’ – has been unfavourably contrasted with middle-class ideals of respectabil- ity. that many young women are surgically cultivating such a body makes them ‘ostentatious’ and ‘vulgar’ for some feminists, and ‘grotesque’ for others. in this language we can see the classed operations of feminism most acutely and can begin to understand the sense of alienation from feminism that many young women feel. to define these women as ‘victims’ of the beauty industry and motivated by the pain of being outside normative (classed and raced) ideals of beauty effectively erases their subjectivity. yet feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com these are exactly the women that feminists claim to represent. young women who admire celebrities such as the uk ‘glamour model’ jordan for her self-determination, business skill and success, as well as her glamorous and hedonistic lifestyle, are bound to be disaffected by feminists who deny jordan agency simply because her choices contrast with their own sense of agency (frequently rooted in self-improvement and respectability). it is therefore vitally important to recognize that contemporary women who routinely adopt the markers of hypersexualization associated with classed and racialized bodies (such as buttock implants or collagen lips) are not passive but active and desiring (not just desirable). aesthetic surgery is most frequently read as a technology through which each woman’s aspirations are discursively directed towards the same (white, western) ideal of beauty or normality. because of this, writers like kathy davis have become lodged within the same discursive frame as medical policy-makers advocating that those experiencing psychological distress through failing to achieve an ideal should be allowed access to free ‘corrective’ surgery on humanitarian grounds. in this model, however, the patient’s subjectivity (her ability to choose as an active consumer-citizen) is erased. thus the aesthetic surgery patient is effectively placed at the centre of a double bind. in asserting her subjectivity, by articulating surgery as a choice, she automatically excludes herself from free (and therefore legitimate) surgery. to qualify legitimately for surgery she has to relinquish her will, presenting herself as a victim of the patriarchal ideologies of idealized femininity that feminists identified and which are now ubiqui- tously accepted. however, for many consumers of aesthetic surgery, ‘enhancements’ may be about standing out rather than blending in. this position makes more sense when we relate aesthetic interventions to the increasing importance of the body in the workplace. of course, bodies have always been commodified, for their strength, dexterity or speed, for instance, but in the new climate of the interactive service encounter, bodies (both women’s and men’s) have become increasingly commodified for the way that they look. there is a vast literature detailing the controls on women’s bodies and sexualities at work, but this literature sometimes forgets that appearance also conveys status, authority, control, success. thus, the well-managed body can accrue significant benefits. what is interesting in this respect is that unlike the s career woman whose body was masculinized through the power suit – her femaleness erased (entwistle, ) – the career woman today actively flaunts her sexually marked body. it would be a mistake for feminists to interpret this phenomenon as merely another example of women being reduced to objects for the delectation of their male clients or colleagues. instead this may be exactly the body that pioneering women in the s were still too fragile to expose. this body, we argue, rejects notions of respectable, passive sexuality (and its inherent class and race divisiveness) as well as masculinist codes of dressing. instead it celebrates the feminine and is assertive enough to override the lingering anxieties of men who would erase it. outside of work, glamour has arguably replaced beauty as an ideal. for holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com respondents in bev skeggs’ ( ) research, glamour was a risky strategy because it easily slid into tartiness. however, young women today are no longer expected to ‘save themselves’ for the right man and having a sexual past now goes without saying. thus, glamour no longer carries the same risks it once did. instead glamour is something that women (and men) can participate in often or rarely; it can be taken up or thrown off at leisure. glamour can be expensive, but it can also be cheaply emulated. glamour scorns the natural body and natural beauty so celebrated in bourgeois culture. glamour is not classed, or ‘raced’, or gendered – boyz can be glam- orous and then there’s lesbian chic – glamour is democratic. if ever we need proof that aesthetic surgery is about more than psychological pain, we only have to look at last year’s newspaper reports of brazil running out of silicone a month before the rio carnival (fagg, ). before we are seen to be unequivocally celebrating aesthetic surgery, however, we must point out its limitations. one thing that cannot be open to dispute is the profoundly misogynistic culture of many cosmetic surgeons (although see davis, for an account of a pioneering female surgeon in the early th century who developed facelifts for women in order to prolong their careers). the negotiation between women and their surgeons is a profoundly asymmetrical one and, in the tricky area of what might ‘suit’ a patient, the doctor’s (normative) judgement and expertise are frequently the deciding factors. furthermore, the discourse of self- improvement expounded by clinics and young women alike is a highly individualistic one. in western culture bodies are assumed to exteriorize an inward depth. western bodies are not so much a collective project of inscription as personal projections of the self. thus, aesthetic surgery is a profoundly individualized endeavour. it is this very individualism that can prevent us from collectively overturning hierarchies of beauty – whatever those currently might be. furthermore, bodies are never fully authored by individual subjects, but are shaped by historical and social conditions. even if beauty becomes a more pluralistic conception, the impetus to work on the body in order to demonstrate an enterprising self may become ever more intense for all of us (men included). in the end, then, the surgeons are likely to be the real winners, but in the meantime we must not ignore the very real sense of agency, albeit within highly stratified social locations, that aesthetic surgery can provide. one thing is clear: it is time that we begin to question the useful- ness to feminism of binary models of gender in terms of transcendence and immanence, mind and body, subject and object, active and passive, as it seems these oppositions are just as likely to limit our enquiries as to enhance them. as we showed in our introductory discussion of beauty and the grotesque, such binaries can be used just as easily to reinforce class and race hierarchies within feminism as to undermine masculinist concepts of women. equally importantly, feminist discourses of victim- ization or internalized oppression are likely to alienate a generation of young women for whom sexual self-determination, expressed through the glamorous body, is a central component of identity, associated with pleasure and success. feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com notes . the term aesthetic surgery is used in place of the term cosmetic surgery to avoid the pejoratively gendered connotations of the latter. . this position also explains why many white middle-class women in general are renowned for asking the question ‘does my bum look big in this?’, an affirmative answer stripping any woman of the respectability she gained by accepting her opposition to ‘other women’. . as gollaher ( ) describes it, ‘visible glans in an uncircumcised man was taken as evidence of sexual arousal and was thus considered indecent within the [greek sporting] arena. to prevent mishaps, many athletes wore the kynodesme, a strand of colored string that looped around the foreskin, closing it tightly over the glans’ (p. ). this code placed jewish men at a disadvantage in competitive games and led to circumcision reversals. the first method of reversal was what the greeks called epispasmos and involved stretching the foreskin over the glans and then binding it at the end. the second more permanent option involved cutting away the connecting tissue between the glans and remaining foreskin, turning the prepuce inside out and pulling the exposed tissue towards the tip of the glans. this operation is well documented by aurelius conelius celsus in his celebrated first-century work de medicina (gollaher, : ). . for instance, in lee jeans ran an advertisement campaign in the uk with a poster of a woman resting her stiletto on a man’s bare behind with the strapline ‘put the boot in’, remodelling this emblem extraordinaire of women’s oppression by offering women the power of having the phallus (through penetration). madonna’s reclamation of the corset has also been well documented (fiske, ). an advertisement by the cosmetics brand no also featured a woman with cropped hair and army uniform advising, ‘it’s not make-up, it’s ammunition’. . jordan aka katie price is a highly successful uk glamour model famous for her large prosthetically enhanced breasts and drunken escapades. her popularity was further enhanced when she starred in the widely viewed uk television show i’m a celebrity, get me out of here!, where she met her current husband, the singer peter andre (price, ). references adkins, lisa ( ) gendered work: sexuality, family and the labour market. milton keynes: open university press. aristotle ( ) the complete works of aristotle, ed. jonathan barnes. princeton, nj: princeton university press. bakhtin, mikhail ( ) rabelais and his world. bloomington, in: indiana university press. bartky, sandra lee ( ) femininity and domination: studies in the phenomenology of oppression. london: routledge. beauvoir, simone de ( ) the second sex. london: vintage classics. black, paula ( ) the beauty industry: gender, culture, pleasure. london: routledge. blumenbach, friedrich ( , repr. ) on the natural varieties of mankind. new york: bergman. bordo, susan ( ) unbearable weight: feminism, western culture, and the body. berkeley, ca: university of california press. holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com bordo, susan ( ) ‘material girl: the effacements of postmodern culture’, pp. – in roger lancaster and micaela di leonardo (eds) the gender/sexuality reader: culture, history, political economy. london: routledge. butler, judith ( ) undoing gender. london: routledge. clinic beaucare ( ) url: http://www.kliniekbeaucare.com/belgium/ cosmetic_surgery.html (accessed june ). corrigan, peter ( ) the sociology of consumption. london: sage. davis, kathy ( ) reshaping the female body: the dilemma of cosmetic surgery. london: routledge. davis, kathy ( ) dubious equalities and embodied differences: cultural studies on cosmetic surgery. lanham, md: rowman and littlefield. denfield, rene ( ) the new victorians: why young people are abandoning the women’s movement. london: simon & schuster. dollimore, jonathan ( ) sexual dissidence: augustine to wilde, freud to foucault. oxford: oxford university press. dworkin, andrea ( ) pornography: men possessing women. london: the women’s press. entwistle, joanna ( ) ‘power dressing and the fashioning of the career woman’, pp. – in m. nava, i. macrury, a. blake and b. richards (eds) buy this book: studies in advertising and consumption. london: routledge. fagg, stuart ( ) ‘viva brazil’. url: http://www.lawyersweekly.com.au/ articles/ / c f .asp?type= &category= (accessed july ). fiske, john ( ) reading the popular. london: routledge. gamble, sarah, ed. ( ) the routledge companion to feminism and postfeminism. london: routledge. gilman, sander ( ) ‘black bodies, white bodies: towards an iconography of female sexuality in late-nineteenth-century art, medicine, and literature’, critical inquiry ( ): – . gilman, sander ( ) making the body beautiful: a cultural history of aesthetic surgery. princeton, nj: princeton university press. goffman, erving ( ) the presentation of the self in everyday life. new york: doubleday. goldberg, david theo ( ) racist culture: philosophy and the politics of meaning. oxford: blackwell. gollaher, david l. ( ) circumcision: a history of the world’s most controversial surgery. new york: basic books. grosz, elizabeth ( ) volatile bodies: toward a corporeal feminism. bloomington, in: indiana university press. hemmings, clare ( ) ‘telling feminist stories’, feminist theory ( ): – . jeffreys, sheila ( ) beauty and misogyny: harmful cultural practices in the west. london: routledge. krafft-ebing, richard von ( ) ‘congenital sexual inversion in woman’, pp. – in ‘general pathology’, psychopathia sexualis, with especial reference to the antipathetic sexual instinct: a medico-forensic study, th german edn, trans. franklin s. klaf. new york: stein and day. mackinnon, catherine ( ) ‘sexuality’, pp. – in linda nicholson (ed.) feminist theory ( ) at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com the second wave feminism reader: feminist theoretical writings. london: routledge. mcclintock, anne ( ) imperial leather: race, gender, and sexuality in the colonial context. london: routledge. mcrobbie, angela ( ) feminism and youth culture. basingstoke: macmillan. morgan, kathryn pauly ( ) ‘women and the knife: cosmetic surgery and the colonization of women’s bodies’, hypatia ( ): – . mulvey, laura ( ) ‘visual pleasure and narrative cinema’, screen ( ): – . pitts, victoria ( ) in the flesh: the cultural politics of body modification. basingstoke: palgrave macmillan. plato ( ) the symposium. harmondsworth: penguin. price, katie ( ) being jordan. london: blake. ripley, william ( ) the races of europe: a sociological study. new york: d. appleton and co. roiphe, katie ( ) the morning after: sex, fear and feminism. london: hamish hamilton. shildrick, margrit ( ) leaky bodies and boundaries: feminism, postmodernism and (bio)ethics. london: routledge. skeggs, beverley ( ) formations of class and gender: becoming respectable. london: sage. stallybrass, peter and allon white ( ) the politics and poetics of transgression. london: methuen. stone, sandy ( ) ‘the empire strikes back: a posttranssexual manifesto’, pp. – in kristina straub and julia epstein (eds) body guards: the cultural politics of gender ambiguity. new york: routledge. synnott, anthony ( ) the body social: symbolism, self and society. london: routledge. taschen, angelika, ed. ( ) aesthetic surgery. köln: taschen. tate, shirley anne ( ) black skin, black masks: hybridity, dialogism, performativity. aldershot: ashgate. wajcman, judy ( ) feminism confronts technology. cambridge: polity. wilson, elizabeth ( ) adorned in dreams: fashion and modernity. london: i.b. taurus. wolf, naomi ( ) the beauty myth: how images of beauty are used against women. new york: vintage. ruth holliday is director of gender studies at the university of leeds. she has written on work, sexuality, identity, aesthetic practices and interiors. she is currently co-writing a book on the cultural politics of kitsch. address: centre for interdisciplinary gender studies, university of leeds, leeds ls jt, uk. email: r.holliday@leeds.ac.uk jacqueline sanchez taylor lectures in the department of sociology at the university of leeds. she writes on sex tourism, prostitution, race and migration and the body and has conducted extensive research in the caribbean, latin america, india and south africa. holliday & sanchez taylor: aesthetic surgery as false beauty at tehran university on april , http://fty.sagepub.comdownloaded from http://fty.sagepub.com doi: . /s - ( ) - tilburg university small is beautiful but large is not to be belittled eijffinger, s.c.w.; de haan, j.; koedijk, c.g. published in: european journal of political economy publication date: link to publication citation for published version (apa): eijffinger, s. c. w., de haan, j., & koedijk, c. g. ( ). small is beautiful but large is not to be belittled: reply. european journal of political economy, ( ), - . general rights copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • users may download and print one copy of any publication from the public portal for the purpose of private study or research. • you may not further distribute the material or use it for any profit-making activity or commercial gain • you may freely distribute the url identifying the publication in the public portal ? take down policy if you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. download date: . apr. https://research.tilburguniversity.edu/en/publications/b c - cc - e b-a c-f e db www.elsevier.com/locate/econbase european journal of political economy vol. ( ) – discussion small is beautiful but large is not to be belittled: reply $ sylvester c.w. eijffinger a,b,c , jakob de haan c,d,*, kees koedijk b,e a center, tilburg university, p.o. box , le tilburg, the netherlands b cepr, london, uk c cesifo, munich, germany d department of economics, university of groningen, p.o. box , av groningen, the netherlands e rotterdam school of management, erasmus university rotterdam, p.o. box , dr rotterdam, the netherlands received april ; received in revised form april ; accepted april abstract we appreciate that the italian central bank has been able to provide the requested information for our comparison of the research output of european central banks. based on this information, the ranking of the italian central bank improves considerably. still, many small central banks have a better research performance than the banca d’italia and, after recomputation, our previous conclusion that ‘‘small is beautiful’’ is not compromised. d elsevier b.v. all rights reserved. jel classification: e keywords: central banks; research . introduction angelini ( ) argues in his comment on our paper that, due to inadequate information, our ranking of central banks in terms of their research output is inaccurate. the data provided by the italian central bank and updated information we received from other central banks allow us to update of our evaluation of the quantity and quality of the - /$ - see front matter d elsevier b.v. all rights reserved. doi: . /s - ( ) - $ doi of original article s - ( ) - , s - ( ) - . * corresponding author. department of economics, university of groningen, p.o. box , av groningen, the netherlands. tel.: + - - ; fax: + - - . e-mail address: j.de.haan@eco.rug.nl (j. de haan). s.c.w. eijffinger et al. / european journal of political economy ( ) – research activities of various central banks. the analysis is based on the frequency of publications by employees of central banks in peer-reviewed professional economics journals. . methodology as we explained in our paper, we sent all eu central banks a questionnaire in which we asked a number of questions relating to both the number of staff employed by the central bank and the scientific journals in which the staff had published papers. we followed the same procedure for all central banks. we did not independently gather this information ourselves. we judged that self-assessment and self-reporting would ensure reliable information. one of the central banks that could not provide all the requested information was the italian central bank. we are happy that the italian central bank is now able to provide complete information about publications. in the mean time, some other central banks also provided—sometimes even without being asked by us—relevant information. we can therefore update and extend our results. as explained in our paper, we categorized solid economics journals in which central bank researchers had published their research into three classes: top journals, very good table the weighted journal publications per employee of european central banks (including the ecb) for the period – central bank of: total number of journal publications quality-weighted number of articles quality-weighted number of articles per employee in research austria . belgium . denmark . finland . greece ( – ) . ireland . italy . israel n.a. netherlands . portugal . spain . sweden . switzerland n.a. uk . ecb ( – ) . ecb ( – ) . new figures are shown in italics. the other figures are from eijffinger et al. ( ). figures for uk and sweden refer to – . figures for the ecb refer to – or – . in the first case, the publications of the ecb research staff during – were also counted. the swiss central bank only provided the number of researchers, instead of all staff of the economics department. the central bank of israel only provided information on publications and not on staff. s.c.w. eijffinger et al. / european journal of political economy ( ) – journals and good journals. this list of journals is not fixed. good journals that were not in our initial list, as at the time no central bank researchers had published in that specific journal, have been added to the list of journals that has been used in the present update. a top publication delivers three points, a very good publication two points and a good publication one point. we calculated the research output per employee by multiplying the number of journal articles by the respective scores for the journal (either , or ) and dividing the resulting sum by the number of employees. the resulting research output per employee using the additional information we received over the period – is shown in table . the banca d’italia now has a considerably higher ranking than previously. . conclusion notwithstanding the improvement of the ranking of the banca d’italia, our previous conclusion that ‘‘small is beautiful’’ basically still holds for the research departments of the european central banks. researchers from the central banks of greece, switzerland and israel have a relatively high number of publications. references angelini, p., . small is beautiful but large is not to be belittled: a comment on eijffinger et al. [eur. j. political economy ( ) – ] this issue. european journal of political economy . doi: . /s - -( ) - eijffinger, s.c.w., de haan, j., koedijk, k., . small is beautiful: measuring the research input and output of european central banks. european journal of political economy , – . in the case of the banca d’italia, most italian journals have not been included. this procedure was also followed for other central banks for which most national journals were not included. further details are available on request. the total number of employees at the research department of the banca d’italia in was . we fully agree with angelini that the journal of economic behavior and organization is a good journal and have therefore included it in our list, as we did with other good journals. that explains why we have publications for the banca d’italia instead of . small is beautiful but large is not to be belittled: reply introduction methodology conclusion references transcatheter mitral paravalvular leakage closure: a beautiful last resort journal of cardiology cases ( ) – case report transcatheter mitral paravalvular leakage closure: a beautiful last resort martin j. swaans (md)a,*, vincent michiels (md)a, vincent j. nijenhuis (md)a, robin h. heijmen (md, phd)b, jurriën m. ten berg (md, phd)a a department of cardiology, st. antonius hospital, nieuwegein, the netherlands b department of cardiothoracic surgery, st. antonius hospital, nieuwegein, the netherlands a r t i c l e i n f o article history: received february received in revised form june accepted june keywords: paravalvular leakage percutaneous intervention three-dimensional echocardiography mitral valve a b s t r a c t we describe a case of a -year-old patient with rheumatic heart valve disease who was treated with double valve replacement (both aortic and mitral) twice. two months after the second operation she developed a severe mitral paravalvular leakage (pvl) leading to cardiogenic shock for which she was hospitalized in the intensive care unit. multiple weaning efforts proved to be unsuccessful because of persistent hemodynamic instability caused by the severe pvl. since re-redo cardiac surgery would have meant an unacceptable high peri-operative risk it was decided in the heart team to close the pvl by a transcatheter technique. this was done successfully and led to a spectacular hemodynamic improvement. just h after closure of the pvl she could be discharged from the intensive care unit and the day after the procedure she came walking into the echocardiography laboratory for an echocardiographic evaluation. this case demonstrates not only the feasibility of transcatheter closure of a pvl but also that this can be a true life-saving act. � japanese college of cardiology. published by elsevier ltd. all rights reserved. contents lists available at sciencedirect journal of cardiology cases j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j c c a s e introduction a paravalvular leak (pvl) is the consequence of an incomplete sealing between the sewing ring and the valvular annulus. for mitral valve prostheses, its estimated incidence is about – %. although most pvls are asymptomatic, – % of patients exhibit serious clinical consequences, which may consist of hemolytic anemia, infective endocarditis, or congestive heart failure as in our patient [ ]. currently, the gold standard treatment is redo cardiac surgery involving either repair of the leak or re-replacement of the valve. the current case was deemed to be too high risk for redo surgery by our heart team, and she was treated with a transcatheter technique. three approaches can be used: retrograde transapical, antegrade transseptal, or retrograde aortic. based on the two largest case series, technical success ranges from % to * corresponding author at: department of cardiology, st. antonius hospital, koekoekslaan , nieuwegein, the netherlands. tel.: + ; fax: + . e-mail address: m.swaans@antoniusziekenhuis.nl (m.j. swaans). http://dx.doi.org/ . /j.jccase. . . - /� japanese college of cardiology. published by elsevier ltd. all rights % with a clinical success rate of almost % and a major adverse event rate of less than % at days after the procedure [ , ]. consequently, transcatheter pvl closure might be an appropriate alternative for redo surgery in patients deemed at too high risk. case report a -year-old female patient of north-african origin had a mechanical aortic (sorin carbomedics top hat mm; sorin, milan, italy) and mitral (sorin bicarbon mm) valve implanted because of rheumatic heart valve disease years before the current presentation. because of dysfunction of the mechanical mitral valve prosthesis due to excessive pannus formation, she underwent redo mitral (edwards perimount mm; edwards, irvine, ca, usa) and aortic (sorin mitroflow mm) valve replacement (the latter was functioning properly but was removed to be able to carry out the redo mitral valve replacement safely). both procedures were carried out in another hospital. initially there was an uneventful postoperative recovery and she went home clinically well. two months afterwards she was hospitalized because of cardiogenic shock with pulmonary edema secondary to reserved. http://crossmark.crossref.org/dialog/?doi= . /j.jccase. . . &domain=pdf http://crossmark.crossref.org/dialog/?doi= . /j.jccase. . . &domain=pdf http://dx.doi.org/ . /j.jccase. . . mailto:m.swaans@antoniusziekenhuis.nl http://www.sciencedirect.com/science/journal/ www.elsevier.com/locate/jccase http://dx.doi.org/ . /j.jccase. . . fig. . three-dimensional transesophageal echocardiography (left atrial view with color flow) after closure showing only a trivial residual regurgitant jet between the two vascular plugs. mv, mitral valve; p , plug ; p , plug ; arrowhead, regurgitant jet. fig. . three-dimensional transesophageal echocardiography (left atrial view with color flow) before closure showing massive paravalvular regurgitation on the posterolateral side of the mitral valve bioprosthesis. mv, mitral valve; arrowheads, regurgitant jet. m.j. swaans et al. / journal of cardiology cases ( ) – an important mitral pvl. transesophageal echocardiography showed a large defect on the posterolateral side of the mitral valve prosthesis causing severe pvl (fig. ). there was no significant valvular mitral regurgitation, a normal functioning aortic bioprosthesis and a preserved left ventricular ejection fraction. the patient was transferred to the cardiac intensive care unit of our hospital where she was mechanically ventilated maintaining a high need of vasopressors, inotropics, and loop diuretics despite the implantation of an intra-aortic balloon pump. multiple weaning efforts were unsuccessful. given the high risk of re-redo cardiac surgery (euroscore ii: %), the heart team decided to treat her by means of a transapical, transcatheter technique to close the pvl, held responsible for the current therapy-resistant pulmonary edema. this procedure was done under general anesthesia, starting with a small left anterolateral thoracotomy to expose the left ventricular apex. a purse string suture with pledges was placed, together with a -french sheath. the defect was easily crossed with a hydrophilic guidewire and two amplatzertm vascular plugs iii were implanted ( and mm – aga medical corporation, plymouth, mn, usa) which resulted in an almost complete closure of the pvl, leaving only a small regurgitant jet between the two plugs (figs. and ). during the hours following the procedure a spectacular hemodynamic improvement ensued which permitted fig. . three-dimensional transesophageal echocardiography (left atrial view) after successful positioning of the two vascular plugs. mv, mitral valve; p , plug ; p , plug . a rapid weaning from the inotropics, vasopressors, diuretics, and ultimately from mechanical ventilatory support. the next day she could even walk to the echocardiography laboratory for a postprocedure evaluation. discussion in this case, we performed a retrograde technique via transapical approach to close a mitral pvl. in the literature however, the transfemoral approach with or without an arterio- venous loop is mostly described [ – ], although transapical transcatheter pvl closure has increased in popularity [ ]. in our experience, the transapical approach offers a more direct manipulation of the wires resulting in a more controlled positioning and release of the plug. furthermore, multiple guide- wires may be positioned through the pvl(s) to release the plugs in a serial manner, without the difficulty to pass a residual pvl again and risking migration and/or embolization. when using one catheter, the previous plug has to be released before implanting the subsequent plug as was performed in the current case. when using more than one catheter, multiple plugs can be released simultaneously decreasing the risk of migration and enabling repositioning in case of malpositioning or inadequate closure. although a number of unsuccessful procedures have been described [ – ], this case report emphasizes that severely symptomatic refractory heart failure can be a hard indication for closure of a pvl given the fast and complete clinical recovery after closure of the defect. furthermore it demonstrates the feasibility and the efficacy of transcatheter pvl closure, even when multiple devices have to be used to close the leak properly avoiding the risks inherent to redo cardiac surgery. funding no funding source relevant to this case report to be declared. conflict of interest the authors declare no conflict of interest. m.j. swaans et al. / journal of cardiology cases ( ) – references [ ] kliger c, eiros r, isasti g, einhorn b, jelnin v, cohen h, kronzon i, perk g, fontana gp, ruiz ce. review of surgical prosthetic paravalvular leaks: diagnosis and catheter-based closure. eur heart j ; 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[ ] taramasso m, maisano f, latib a, denti p, guidotti a, sticchi a, panoulas v, giustino g, pozzoli a, buzzatti n, cota l, de bonis m, montorfano m, castiglioni a, blasio a, et al. conventional surgery and transcatheter closure via surgical transapical approach for paravalvular leak repair in high-risk patients: results from a single-centre experience. eur heart j cardiovasc imaging ; (may) [epub ahead of print]. [ ] arzamendi d, li ch, serra a. late embolization of a vascular plug iii device after mitral paravalvular leak closure. catheter cardiovasc interv ; :e – . [ ] carnero alcázar m, maroto castellanos lc, rodrı́guez hernández je. failed percutaneous closure of a mitral prosthesis paravalvular leak. rev esp cardiol (engl ed) ; : . [ ] alfirevic a, koch cg. failed closure of paravalvular leak with an amplatzer occluder device after mitral valve replacement. anesth analg ; : – . http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref transcatheter mitral paravalvular leakage closure: a beautiful last resort introduction case report discussion funding conflict of interest references pancreatic β‐cell: the beauty of being plastic e x p e ri m e n ta lp hy si o lo g y exp physiol . ( ) pp – viewpointviewpoint pancreatic β-cell: the beauty of being plastic ernest adeghate email: eadeghate@uaeu.ac.ae type diabetes mellitus (t dm) is a chronic endocrine disorder affecting more than million people worldwide. the prevalence of t dm continues to rise in many parts of the world, partly because a lot of people are enslaved to a sedentary lifestyle and inappropriate diet. genetic factors also play a role in whether an individual develops t dm or not. a strong interaction between genetic and environmental factors in the development of t dm has been reported (adeghate et al. ). irrespective of which factor is to be blamed, the key molecule in the pathogenesis of t dm is insulin. it is a major hormone of the endocrine pancreas that plays an important role in the metabolism of carbohydrate, but also has a say in how protein and fat are utilized. optimal insulin secretion and action are crucial to the maintenance of normoglycaemia. in the absence of intact and adequate insulin, an individual is condemned to developing t dm. what, then, is the driving force behind the secretion and effective insulin molecule? the pancreatic β-cell of the islets of langerhans must be viable and in sufficient numbers and mass to be able to produce intact insulin in adequate quantities. an ideal pancreatic β-cell that will not put an individual in danger of developing t dm must also be smart enough to adapt to the variations in the level of blood glucose in a timely and calibrated manner. it must also be able to maintain normoglycaemia during a variety of endeavours ranging from intense physical activity to fasting. the plasticity of insulin release in different metabolic conditions has been examined largely in small animal models (del zotto et al. ; alonso et al. ). however, the mechanism by which insulin plasticity is executed is complex and has been poorly understood. the article by gartford et al. ( ) in the may issue of experimental physiology used sheep, a large-animal model, to examine the mechanisms of insulin plasticity. this is the first time that a large-animal model, with a semblance of human size, has been used to investigate how pancreatic β-cell plasticity is achieved. gatford et al. ( ) provide compelling evidence that the sheep model adapted to days of continuous, moderate hyperglycaemia by increasing glucose and arginine-induced insulin release rather than initiating an increase in pancreatic cell mass. their findings were supported by techniques such as steady- state infusion, immunofluorescence (for β-cell mass) and radioimmunoassay (for insulin). insulin sensitivity, blood glucose level, glucose tolerance, body composition and growth of several organs were also determined. this novel observation contradicts previous reports, where large and significant increases in pancreatic β- cell mass were observed after rodent models were challenged with hyperglycaemia (alonso et al. ). the article by gatford et al. ( ) shows that pancreatic β-cells are smarter than previously thought, because they respond to chronic glucose challenge by working more efficiently rather than initiating an increase in number. this appears to make sense, because it is physiologically easier for the body to handle variations in function than accumulated cell mass. what would the islet do with the extra pancreatic β-cells when the individual is fasting or exposed to low glucose levels? more importantly, gatford et al. ( ) showed, for the first time, that insulin sensitivity was not altered in the course of chronic glucose challenge. this is in sharp contrast to reports on rodent models, where a significant decrease in insulin sensitivity was observed after a glucose load (topp et al. ). this is a change in paradigm in the way the plasticity of the pancreatic β-cell is viewed. the conclusion of the study has a wider ramification, because plasticity has also been observed in other cell types. it is well known that neurons can adapt to different environmental conditions and produce novel transmitters if and when challenged by a new millieu. what could be the way forward in further exploring the mechanism(s) by which pancreatic β-cells adapt to changes in the level of blood glucose? the limit of the plasticity of pancreatic β-cells will also be of interest in future studies. for example, how would the β-cell respond in an environment of constant and severe hyperglycaemia, ageing and many other epigenetic and environmental factors? a look at a different animal model may also be helpful in the search for a better understanding of the plasticity of pancreatic β-cells. the sheep is a ruminant and may therefore, not experience the wide variations in blood glucose concentrations seen in humans, because of a constant and trickle supply of energy substrates from the gastrointestinal tract. the use of pig might be a preferred model because they are omnivores, have a similar size and eat sporadically like humans. the study by gatford et al. ( ) shows that further research into the mechanism of pancreatic β-cell plasticity will probably focus more on the functional aspect of insulin release and its effect on target cells rather than on an increase in cell mass. transcriptomic, proteomic and/or peptidomic approaches that examine the nature and function of genes expressed and of proteins/peptides released by pancreatic β-cells after exposure to chronic hyperglycaemia may be used to address the molecular basis of the issues raised in this valuable sheep model. references adeghate e, schattner p & dunn e ( ). an update on the etiology and epidemiology of diabetes mellitus. ann n y acad sci , – . alonso lc, yokoe t, zhang p, scott dk, kim sk, o’donnell cp & garcia-ocaña a ( ). glucose infusion in mice: a new model to induce β-cell replication. diabetes , – . doi: . /expphysiol. . c© the author. experimental physiology c© the physiological society exp physiol . ( ) pp – pancreatic β-cell: the beauty of being plastic del zotto h, borelli mi, flores l, garcı́a me, gómez dumm cl, chicco a, lombardo yb & gagliardino jj ( ). islet neogenesis: an apparent key component of long-term pancreas adaptation to increased insulin demand. j endocrinol , – . gatford kl, de blasio mj, how ta, harland ml, summers-pearce bl & owens ja ( ). testing the plasticity of insulin secretion and β-cell function in vivo: responses to chronic hyperglycaemia in the sheep. exp physiol , – . topp bg, mcarthur md & finegood dt ( ). metabolic adaptations to chronic glucose infusion in rats. diabetologia , – . c© the author. experimental physiology c© the physiological society Бруклин Колеџ, Бруклин, Њујорк, САД Џон Џеј колеџ, Њујорк, Њујорк, САД doi . /kultura p УДК . : . МекКвин А. прегледни рад ГЛОБАЛНА МОДА – МОДА БЕЗ ГРАНИЦА: ДИВЉАЧКА ЛЕПОТА АЛЕКСАНДРА МЕКВИНА Сажетак: Да на шње де мо крат ско дру штво се од ли ку је нео ли бе ра ли змом, гло ба ли за ци јом и мул ти кул ту рал но шћу. Да ли је ово дру штво за и ста сло бод но и отво ре но ка квим се при ка зу је, или још увек по сто ји за пад њач ки цен три зам, а сто га и Дру ги, са мо у при кри ве ном об ли ку? У ова квом ‘ли бе рал ном’ дру штву и ње го вој гло ба ли за ци ји, гло ба ли зо ва на је и мо да. Али да ли ову моду, попут модних ли ни ја Алек сан дра Мек кви на, мо же мо на зва ти ‘гло бал ном’, и ако мо же мо на ко ји на чин се она ис ка зу је? Да ли је она ‘мо да без гра ни ца’ амал гам рав но прав но из ме ша не свет ске мо де или је пак не што дру го? Ко од лу чу је ко ја мо да ће би ти про гла ше на гло бал ном ући у ар хив? Исто риј ски гле да но, умет ност, а та ко и при ме ње на умет ност, укљу чу ју ћи и мо ду, увек је го во ри ла из дис кур са сво је кул ту ре, дру штва, од но сно дис кур са по ли ти ке, те је све сно или не све сно увек има ла ак тив ну уло гу у кон струк ци ји и очу ва њу дру штве них по ре да ка и њихо вих вред но сти. Гло бал на мо да, та ко, та ко ђе има уло гу у очу ва њу свог по рет ка нео ли берал ног по рет ка. Кључнеречи: гло ба ли за ци ја, гло бал на мо да, Дру ги, ег зо тич ност, нео ли бе ра ли зам, ар хив МИЛЕНА ПОПОВ МИЛЕНА ПОПОВ Увод Демократско друштво, садашњи свеприсутни друштвени поредак,нијепотпунослободнодруштво(каоштожелида сепредстави),већусебисадржидуалност‘слобода/несло бода’. Мајлс(МаlcоlmМilеs)стогапита:“Далијеуметник слободанутаквомпоретку.Илидалијеуметничкапракса деоовихпреговора?” Уметностјенаразненачиневезаназа системиукљученауњега,понекадсвесно,апонекадине свесно.Токомисторије,уметностјеилиподржаваласистем, каонапример,уметностсоцреализмакоја јесвеснопро пагираласоцијалистички систем,или амерички апстракт ниекспресионизамкојијенесвеснопропагираоамерички напредакикапитализам(односносистемгајекористиоу пропаганднесврхе),илијеуметност,напримеруслучају авангарднихпокрета,покушаваладапроменисистемидру штво.Међутимпонекадсеовадваприступастапајууједан (односно,системасимилујепобеђујеуметност),например услучајурускогконструктивизмаилииталијанскогфутури зма,којисубилиавангарднипокретикојисусезалагализа напредакианархију,дабикаснијеуједноммоментуподр жалисвојусупротносттоталитарнисистем.Уметносттако увекнанекиначинимаактивнуулогууконструкцијииочу вањудруштвенихпоредака. Системодуметностиправиинституцију,којомонуправља дајућијојвредност.Естетикајетакодеополитичкепрак се,као“формаетике”иликао“естетикапостојања”. Преко уметничкихинституцијапопутмузеја,галерија,библиоте ка,кинотека,системархивираоноштоодредикаовисоку уметност–небилије“сачувао”одзабораваиизложиојеза погледмногимгенерацијама,доксдругестранеовајархив реагујекаоагентсмртиуметности,јерјојодузиманесамо тржишнувредностконзервирајућије,већјојскидаиоштри цуавангардекритике.Револуцијатако“једесвојудецу”, доксесистемсамообнавља. ПремаЏејмсону(frеdricЈаmеsоn)“културајествармеди ја”, јеруданашњевремевисокетехнологије,медијидоми нирајусвакодневицом,тесистемпрекомедијасервирасве штожели,паикултуру.Свештојеприказаноумедијима, laclaue.,eman ci pa tion(s),verso,london ,str. . milesm.,cri ti cal prac ti ce: art, in ter ven tion and po wer,routledge,new york . foucaultm.,di sci pli ne and pu nish: the birth of the pri son,penguin,har mondsworth ,рр. . jamesonf., the ge o po li ti cal aest he tics. ci ne ma and spa ce in the world system,indianauniversitypress,bloomington ,рр. . МИЛЕНА ПОПОВ постајереалностивредност.Медијису“прозорусвет”пре кокогаљудиданассазнајуодругимнародимаињиховим културама. Али медији “емоционализују простор, место, кретањаиидентитете,чимеутичунагледаочевуперцепци ју…Визуелнимедијипрезентујуиреконструишуспецифи чанначинвиђењакојисасобомносиисторијскипртљаг”. Натајначинмедијиглобализујусветширећиинамећући доминантанпогледнасвет(западнакултурнаубеђењаиста вовекаодоминантанпогледнасвет–јединииправи). Акојекултураствармедија,медијииграјуогромнуулогу усавременојуметности,атимеипримењенојуметностии модикаоједнојодњенихграна.Постављасепитање:каква јеулогамодеуоваквојглобализацији?Далимодаможеби тиглобалнаидемократскамешањеммоднихстиловаразли читихкултура,апревасходноутицајем“егзотичне”модена западнувисокумоду? Умет ност у по ли тич ком дис кур су Уметностиполитикасуодувекбилеускоповезане,итона различитеначине.Немогућејеодвојитиуметностодсоци јалногмиљеаукоменастаје,каоштониживотникаданије сам“голи”живот,већјеформаживотаначинживотајеу ствариживот. Индивидуакојастварауметничкаделаједео некогдруштваинекекултуре,аусвакомдруштвупостојеи односимеђуиндивидуама(каоимеђудруштвимаикултура ма)–по ли ти ка.Уметниккаоиндивидуаудруштвуимасвој статусутомдруштву,тењеговауметностнастајеуокви рутогстатуса,тогдис кур са.Стогајенемогућетумачитии разуметиуметностбезразумевањадруштвенепозадине,као икултуреукојојтауметностнастаје,односнонемогућеје одвојитиуметничкидискурсодполитичкогдискурса. Уметност често описује, критикује или велича социјалне тренуткеукојимасерађа,чакиакојеонаl’аrt pоur l’аrt. Свакауметностјестогаувећојилимањојмериангажова на.Доксједнестранеавангардатежидамењадруштво,да изградиједнопосвеноводруштвокојећеонауредитипо свомнахођењуgеsаmtkunstwеrk, сдругестранеуметност Исто,стр. . agambeng.,me ans wit ho ut end: no tes on po li tics,universityofminneso tapress,minneapolis . ge samt kun stwerkјенемачкитермин,интернационалноприхваћенесте тички термин који означава тотално уметничко дело и синтезу свих уметности.ТерминпрвипутупотребљаванемачкиписацифилозофК. Ф.Е.Трандорф.Терминсечестокористиу/оВагнеровимделима,есте тичкимидејама,алииоХофмановој,авангарднојархитектуриисвеобу хватномдизајну. МИЛЕНА ПОПОВ тоталитарногдруштватежидаочувадруштвоукомнаста је,величајућига–про па ги ра ју ћига.Уметностјетако,хте ла–нехтела,деодруштваидео си сте ма–политикетог друштва,чакиакогажестококритикује.Крозуметничке институцијеитржиште,уметностјеконтролисанаодстране политичкогсистема.Уметничкеинституције,апонајвише музеј(исличниархиви)одређујукојауметностћебитисма транависокомуметношћуиостатисачуванакон зер ви са на умузејимазапрезентацијусадашњиминарeднимгенера цијама.Архивкаоформаиинституција,којуподржавадр жава,одређујекојауметничкаделасувредначувања.Ове одлукеивредностисемењајуиреинтерпретирајууразли читимепохама.Дерида(jacquesderrida)архив видикао субјективно „наслеђе“система. По пореклу речи (грчки „аrkh“)онојеприрода,онтологија,историја,алииместоса когсевладаидоносезакони.Фуко(Мichеlfоucаult)зараз ликуодњега,архиввидиудискурзивномсмислукаонеин дивидуалнуактивност(анонимну),алислажесесаДеридом дајеархивнеописивусвомтоталитету: „Очигледноједасеархивједногдруштва,културе,циви лизације или пак епохе не може исцрпно описати (...) не можемоописатининашсопствениархив,поштоговори моунутарњеговихправила,ипоштооноштоможеморећи –ионсамкаопредметнашегдискурса–онодњегадо бијасвојеначинепојављивања,својеобликеегзистенције и коегзистенције, свој систем гомилања, историчности и нестајања“. Архивјекаоинституцијаснажанмеханизаммоћи,којије отпоранинанападеавангарде, јерсдругестране,архив конзервирајућиуметност–уклањауметностсатржишта,а тимејојбришенесамотржишнувредноствећислободу иекспресијупоруку.Например,модајечестобунтовна (критикујући систем и његове норме), чак и висока мода (илибарнаизглед)загенерацијеукојиманастаје,попутКо коШанел(cоcоchаnеl)којајебилабунтовнапочеткомсво јекаријере,јерјепрвипут(назападу)креиралапанталоне зажене,каоиИвСенЛоран(yvеssаintlаurеnt)сасвојом prêtàpоrtеr модом.Касније,овиистимодниавангардисти постајукласици,чимимтржиштесистемсламаоштрицу авангарде.Насличанначинавангардностмодебунтовних derrida j., ar chi ve fe ver, university of chicago press, chicago , рр. , . ФукоМ., Ар хе о ло ги ја зна ња,МладенКозомора,Плато,Београд , стр. . Биргер П., Те о ри ја аван гар де, Народна Књига/АЛФА, Београд , стр. . МИЛЕНА ПОПОВ супкултурапопутхипиипанкмоде,сламасеуправоонда кадасеовамодале ги ти ми зу је–аси ми лу јесвојимуласкому архив–(високумоду),кадаинспиришеисвакодневнумоду. Систем,какоЖижеккаже,самсебеобнављарециклира, а нарочитојеутомевештданашњили бе рал ни ка пи та ли зам, односнонеолиберализам. Гло бал на мод на ли ни ја Напрвипогледмоданеизгледакаонештоштоимавезеса политиком,већизгледасамокаопотрошачкипроизвод,до колица,докустварииграмноговећуулогунаразличитим политичким пољима. Као што свака уметност настаје из дискурсадруштваисистема,такоипримењенауметност,а тимеимоданастајууоквируистогдискурса.Штаљудино сејенајвидљивијиинајосетљивијидруштвенипоказатељ пола,статуса,класе,нације,образовања,исл,каоисавре менеглобализације.Модакаоивисокауметност,чакивише одње,иматакођеприкривенуулогукојујојсистемнамеће. Онајенајчешћезабаваспектаклкојадржимасуупокорно сти,ачиниибитносредствоглобализације,тенаизгледне познајегранице–уједињујесвет. Утакозваном‘либералномкапитализму’сепропагирајуве ликеслободекојесеназивајуједномречју–демократија. Ова“слобода”јепакдоброприкривенатоталитарнаглоба лизација,укојојЗападтежиисвевишеостварујетоталну асимилацијусвихкултура.Далијестогаглобалнауметност устваризападнауметносткојасенамећецеломсветукао права,истинита,савремена–супериорна? Западнауметностикултурасупоказаледаволедасе“ин спиришу”другимкултурама,притомихасимилујућиусвој за пад ни оквир(каонапримертзв.wоrld mu sic).У‘запад ним’очима(јудеохришћанским),култураДру гогје‘егзотич на’–дивљачка,сирова,мистична,атимеизаводљива.Без постојањатогДру гог,западничовекнебизнаокојеонсам. Мизнамокосмоуодносунаоногдругогкојинисмо.Стога јерасизамдискурсирепрезентацијакојагураоногДругог утрећисветнамаргину.ЕнглезикаоштоХол(stuаrthаll) наводи,нисурасистизатоштомрзецрнце,већзатоштобез црнацанемогудавиде,пронађусвојидентитет“морају знатикони су,дабизналикојесу”. Žižeks.,map ping ide o logy,verso,london . halls.,et hni city: iden tity and dif fe ren ce–editedversionofaspeech deliveredatthehampshirecollege,amherst,massachusetts,inthesping of ,www.csus.edu.indiv/i/leekelerh/hall,% ethnicity_identity_and_ difference.pdf. МИЛЕНА ПОПОВ Ро ман тич ни ег зо ти ци зам и при ми ти ви зам Алек сан дра Мек Кви на БиткусасвојимсопственимидентитетомводиојеиАлек сандар МекКвин (Аlеxеndеr Мcquееn), британски модни креатор,којијесједнестраневеличаосвојшкотскииден титетусвојојкритициенглескеполитикепремаШкотској, докјесдругестраневеличаоуправоовубританску(енгле ску)империјалистичкудоминацијунаддругимкултурама, такође ‘инспиришући’ се овим ег зо тич ним – ди вљач ким при ми тив нимкултурамаградећи‘гло бал ну’ мод ну ли ни ју.Овосенарочитомогловидетинаизложби“Дивљачка лепота”,постхумнојретроспективимодеАлександраМек КвинауМетрополитенмузејууЊујорку( .маја– .ав густа ).Самназивовеизложбекојујеорганизоваоку стосЕндрјуБолтон(Аndrеwbоltоn)иназивиМекКвинових колекцијаотомесведоче:То је са мо игра,Џун гла је та мо на по љуитд.Болтонумонографијиоовојизложбиназива МекКвиновумодуРо ман тич ни ег зо ти ци зам и Ро ман тич ни при ми тивизам поредећигасавикторијанскимромантича рима (дендијима) попут Бајрона, који су се инспирисали “егзотиком”. “МекКвиновромантичкисензибилитетјепрошириоњегов хоризонтмаштенесамовременскивећигеографски.Тако јетобилоизауметникеиписцеромантизма,егзотикаје билацентралназањиховрад.Каоњеговисторицизам,Мек Квинјеширокообухватао–Индија,Кина,Африка,иТурска суизазивалењеговумасту.Јапанјебиопосебнозначајанза њега,тематскиистилски.Кимоно,посебно,јебиоодевни предметкојијеонреконфигурисаобескрајно.” МекКвин сетокомсвојекаријеревратионатему„примитивизма,који сеослањаонаидеалоплеменитомдивљакукојиживиухар монијисаприродом“. МекКвинзапочињесвојукаријеру колекцијомНи хи ли зам(пролеће/лето )гдесеинспири шеонимштокустосБолтонназива‘ро ман тич ни при ми ти ви зам’.„Тојебилареакцијанадизајнерекојиромантизирају етничкооблачење,каоМасаиинспирисанехаљиненапра вљенеодматеријалакојеМасаинемогудаприуште.“ Ова колекцијајеукључивалаипознатухаљинуодсинтетичког материјаласаскакавцима,чимејеМекКвин,поБолтону,из неосвојставопроблемугладиусвету.Многимоделииз овеколекцијесуобложениблатом,тесеова„уображеност boltona., alexander mcqueensavage beauty,metropolitanmuseumof art,newyork ,str. . Исто,стр. . Исто,стр. . МИЛЕНА ПОПОВ дизајнера“ понавља у Ешу колекцији (јесен/зима )инспирисанојпознатимбожанствомурелигијиЈору ба,гдесеМекКвин,посебнокапутомодцрнесинтетичке длаке и хаљином од црног коњског репа повезане жутим стакленим перлама, „приближио фетишизацији материја ла“. ОвуфетишизацијунастављауколекцијиЏун гла је та мо на по љу(јесен/зима )инспирисанојТомпсоно вомгазелом.Колекцијајесвојеврсна“медитацијаодинами цимоћи–специфично,односуизмеђупредатораиплена“,а јабихдодала–понајвишеоваколекцијапоказујединамику моћиизмеђудоминантногзападаи„Другог“.Болтоннарав нозападњачкимочимавиди: „Заиста,МекКвиноверефлексијеопримитивизмусучесто представљенеупарадоксалнимкомбинацијама,контрасти рајући„модерно“и„примитивно“,„цивилизовано“и„не цивилизовано“.Причао Ире ре(пролеће/лето )укљу чујебродоломнаморуинасељенајепиратима,конквиста доримаиамазонскимИндијанцима.Типично,МекКвинов наратив прославља и овде природно стање и завршава моралну равнотежу у корист „природног човека“ и „го сподинаприроде“,неспутаногвештачкимконструкцијама цивилизације“. АлиниМекКвинниБолтонневидедајемода(чакможда ивишенегодругеврстеуметности)луксуз,нештоштоније нужно,нештоштојепротивноприроди,екологији,јеркори стисталноновематеријале–ресурсезанештоштонијенео пходно.МекКвинсенаводнозалажеза„природногчовека“, алинеспадауоне, јошувекмалобројнемоднекреаторе, којикористесаморециклиранматеријалзасвојекреације, преферирајућиприроднематеријале,јерсуониусагласно стисаекологијом(биоразградивисуисвојомпроизводњом незагађујусредину).Иакокритикуједругедизајнерекоји се инспиришу Масаи одећом, користећи материјале које Масаинемогудаприуште,онисамкористиелитистичке материјалеиобиљересурсадабиствориоопетнештошто нијенеопходнокаоштојетоМасаиодећа.Онпопуттипич ногвикторијанскогдендија(каојунакХујсмансовогромана Про тив при ро деилимаркизеКасати)уживаусвомлуксузу, алигаистовременоимрзи,теусвојојфетишистичкојизопа ченостисебидајезаправодакористиелементе(идеје)дру гихкултура(којеиаковолисматрапримитивним)иствара своју–новулуксузну„природу“. БолтонА.,нав.дело,стр. Исто,стр. Исто. МИЛЕНА ПОПОВ МекКвин наивно не види своју улогу у глобализацији, ‘реоријентализацији’Оријентаи‘реафриканизацији’Афри ке,теосвојимколекцијамакаже: “Ижелимдабудемискреносветуукомживимо,ипоне кадмојаполитичкаубеђењадолазекрозмојрад.Модамо жебитирасистичка,гледањемнаодећудругихкултуракао накостиме…Тојемалограђанскиистаријешешир.Хај дедапорушимонекегранице…Мојрадћебитиоузима њуелеменататрадиционалногвеза,филигранаизанатства изземаљаширомсвета.Јаћуистраживатињиховезанате, шареиматерјалеитумачитиихнасвојначин…Трудимсе дапомеримсилуету.Дапроменитесилуетузначипромени тимишљењеотомекакогледамо.Штајарадим,јагледам афричкаплеменаиначиннакојисеоблаче.Ритуалењихо вогоблачења...Имамногоплеменскогуколекцијама“. Онјеегзотицизамчестопокушаваодаизразиуконтрастној супротностисазападнимвредностима.Таконапримерна моднојревији То је са мо игра(пролеће/лето )инспи рисансценомиграњашахаизфилмаХа ри По тер и ча роб ња ков ка мен( ),МекКвинпредстављасвојемоделекао азијске(јапанске)моднекреацијекојеиграјушахсаамерич киммоднимкреацијама.Постављасепитањекојезаправо победиоуовојшаховскојигри?Занимљивоједакласичну моднуписту,којајеизмишљенаујапанскомКабукипозори шту,замењујезападњачкомигром–шахом(иакоиоваигра имаисточњачкопорекло,МекКвинсеовдеинспиришењом учистозападњачкомруху–шаховскомигромузападњач комфилмскомспектаклу). Онтакоиовдеизводи“оријен тални”моднистилизњеговогоригиналногконтекстаипо стављагакаопионаузападњачкојигри. За кљу чак Капитализам, а поготово данашњи либерални капита лизам, односно неолиберализам и његов спектакл, како би га Дебор (guy dеbоrd) назвао, или „капиталистички парламентаризам“ по Бадијуу (Аlаin bаdiоu), на исти на чинкаоииндустријскареволуција“уништавајусоцијалне и друштвене структуре, као и законске категорије старих режима;терминикаоштосусуверенитет,право,нација,на род,демократијаиопштавољасадасеодносенанештошто немавишевезесаонимштосутиконцептиозначавали… mcqueen a. and bolton a., alexander mcqueensavage beauty, metropolitanmuseumofart,newyork ,pp. . columbusc.,harry potter and the sorcerer’s stone,color, min,warner brospictures,uk/usa . МИЛЕНА ПОПОВ савременаполитикајеексперименткојидезартикулишеи празниинституцијеиуверења,идеологијеирелигије,иден титетеидруштвауцеломсвету,такодаихондарехабилиту јеиуспостављауиспражњенојформи”. Односно,виђено изугла‘глобалнемоде’:иаковеликоинтересовањезапад њачкихдизајнерависокемодезатрадиционалноодевање другихнарода,превасходноизАзије(почевшиодвремена колонијализма), на први поглед изгледа као демократска формамеђукултурнеразменеидеја,моднаелита(атојеза падњачкамоднаелита–елитацентараглобалнемоћи)пак модудругихнародаозначавакаонештоегзотичноифеми низирано(атимтерминимаимањевредно).Тојеипакмода “Другог”,моданамаргини.Иакоизгледадаазијскатради ционалнаодећаоријентишеглобалнумоду,тајистипроцес глобализације–западнедемократије,оријентализујеазијску модуиАзијце, апоистомпринципукодираиглобализу јеидруге‘неЗападне’народе.Глобалнамоднаинтеракци јаса‘маргиналним’културамаомогућава“привилегованим корисницимакојизнајумалооазијскимљудимаиместима даизбегнуозбиљноангажовањеувезисакултурномсушти номтихстилова”. Такође,оностварановеразликемеђу културамаиутиченаодевањетих‘других’култура. АлександарМекКвинсвојимнаивнимромантизмомиегзо тицизмомнесвеснодоприносиглобализацији.Мода,иако јенаизгледсамоуметничкакреацијаилинеопходназаба ва,уствариигравеомавеликуулогууразнимдруштвено политичкимодносима,аданаснарочитоуглобализацији. ЛИТЕРАТУРА: acords.k. and denorat., cultureandthearts:fromartworldsto artinaction, an nals of the ame ri can aca demy of po li ti cal and so cial sci en ce no. , ,pp. . agambeng.,me ans wit ho ut end: no tes on po li tics,universityof minnesotapress,minneapolis . АрганГ.Ц.,Односмодернеуметностипремаполитичкимидеоло гијама,Сту ди је о мо дер ној умет но сти,Нолит,Београд БиргерП.,Те о ри ја аван гар де,НароднаКњига/АЛФА,Београд . boltona.,ale xan der mcqu e ensa va ge be a uty,metropolitanmuseum ofart,newyork . agambeng.,means without end: notes on politics,universityofminnesota press,minneapolis . niessen s., leshkowich a. i jones c., globalization of asian dress: reorienting fashion,berg,oxford ,str. . Исто,стр. . МИЛЕНА ПОПОВ columbusc.,ha rry pot ter and the sor ce rer's sto ne,color, min, warnerbrospictures,uk/usa . derridaj.,ar ch ive fever: a fr eudian impr ession,universityofch icagopress,chicago . foucaultm.,discipl ine and punish: the birth of t h e pr ison,penguin, harmondsworth . ФукоМ.,Археологија зна ња,МладенКозомора,Плато,Београд . halls.,ethnicity:identityanddifference–editedversionofasp eechdeliveredatthehampshirecollege,amherst,massachusetts,in thespingof ,www.csus.edu.indiv/i/leekelerh/hall,% ethnici ty_identity_and_difference.pdf. jamesonf.,the geopolitical aesthetics. c in ema and spac e in th e world syst em,indianauniversitypress,bloomington . laclaue.,ema nci patio n (s),verso,london . ЛазићР.,Канами , Зеами, Н о бумици и непо знат аутор: Ј апански кл асични теат ар. Но драма: Антолог и ја,приредиоЛазићР., Београд . milesm.,criticalpractice:art,interventionandpower,routledge, newyork . niessens.,leshkowicha.andjonesc.,gl oba lizati on o f asian dre ss: reo ri enting fas hion,berg,oxford . ryerssonscotd.,michaelorlandoyaccarino,the ma rc h es a casati : p ort ra its of a muse,abrams,newyork . zizeks.,map ping ide o logy,verso,london . milenapopov brooklyncollege,brooklyn,newyork johnjaycollege,newyork,usa globalfashion–fashionwithoutborders: savage beauty ofalexandermcqueen abstract today’s democratic society is characterized by neoliberalism, globalizationandmulticulturalism.isthissocietyreallyfreeandopen asitpresentsitself,orcanwestillfindtherewesterncentrism–and hencetheother–butinаveiledform?inthis‘liberal’societyandits globalization,fashionisalsoglobalized.butcanwecallthisfashion, suchasfashionlinesofalexandermcqueen,‘global’,andifwecan, howisitexpressed?isthisfashion‘afashionwithoutborders’an amalgamofequallymixedworldfashions,orisitsomethingelse?who decideswhatfashionisgoingtobedeclaredglobalandentertheglobal archive?historically,artsandappliedartsincludingfashion,havealways spokenfromthecontextoftheirculture,society,politicaldiscourseetc andhaveconsciouslyorunconsciouslyalwaysplayedanactiverolein constructingandmaintainingsocialorderandvalues.so,globalfashion alsohasaroleinmaintainingthesystemitworksin–theneoliberalorder. key words: globalization, global fashion, other, exoticism, neoliberalism, archive s jra .. aging well: treherne’s ‘warrior’s beauty’ two decades later catherine j. frieman , joanna brÜck , katharina rebay-salisbury , sophie bergerbrant , sandra montÓn subÍas , joanna sofaer , christopher j. knÜsel , helle vandkilde , melanie giles and paul treherne school of archaeology and anthropology, australian national university, canberra, australia department of archaeology and anthropology, university of bristol, bristol, uk institute for oriental and european archaeology, austrian academy of sciences, vienna, austria department of historical studies, university of gothenburg, gothenburg, sweden icrea, departament d’humanitats, universitat pompeu fabra, barcelona, spain department of archaeology, university of southampton, southampton, uk umr pacea, university of bordeaux, bordeaux, france department of archaeology, institute of culture and society, aarhus university, aarhus, denmark school of arts, languages and cultures, university of manchester, manchester, uk st stephen’s international school, rome, italy introductory remarks catherine j. frieman over the (slightly more than) two decades that the european journal of archaeology (formerly the journal of european archaeology) has been in print, we have published a number of excellent and high profile articles. among these, paul treherne’s seminal meditation on bronze age male identity and warriorhood stands out as both the highest cited and the most regularly downloaded paper in our archive. speaking informally with friends and col- leagues who work on bronze age topics as diverse as ceramics, metalwork, land- scape phenomenology, and settlement structure, i found that this paper holds a special place in their hearts. certainly, it is a staple of seminar reading lists and, in my experience at least, is prone to provoke heated discussions among stu- dents on topics as far ranging as gender identity in the past and present, theoret- ically informed methods for material culture studies, and the validity of using classical texts for understanding prehis- toric worlds. moreover, in its themes of violence, embodiment, materiality, and the fluidity or ephemeral nature of gen- dered identities, it remains a crucial foun- dational text for major debates raging in european prehistoric archaeology in the present day. european journal of archaeology ( ) , – © european association of archaeologists doi: . /eaa. . manuscript received august , accepted august https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core thus, it seemed pertinent that, as part of the commemoration of our th volume, we should return to our most loved paper to ask why and how it has aged so well, in what ways the debates we are currently having build on its themes, and where new data or interpretations have since enhanced (or challenged) treherne’s compelling narrative. the fol- lowing short articles were solicited as responses to and reflections on treherne’s original article. authors were asked simply to build on treherne’s work and to reflect on how it had impacted their own research and their wider field. these reflections range from reviews of the ongoing signifi- cance of treherne’s ideas to our under- standing of gendered identities in the bronze age (brück, rebay-salisbury, bergerbrant), to the political impact of prehistoric research into gender identity and masculinity (montón subiás, sofaer), and to the identification and social pos- ition of war, warfare, warrior’s bodies, and depictions of warriorhood in prehistoric societies (knüsel, vandkilde, giles). we are also pleased to include a short response by paul treherne, now chair of history at st stephen’s international school in rome, to these reviews and to the ongoing signifi- cance of his postgraduate research for european prehistoric archaeology. gender and personhood in the european bronze age joanna brück paul treherne’s article in the journal of european archaeology for is one of the most influential pieces of work on the bronze age written in the past few decades. it effectively critiqued previous work on prestige goods—arguing, for example, that we need to account for the particular character of the grave goods that accompany high status burials—but it also sustained and crystallized existing models of a bronze age warrior elite. the image of the bronze age warrior is extraordinarily enduring; but it is, in my opinion, highly problematic, for it domi- nates our narratives of the period to the virtual exclusion of alternative interpret- ative frameworks, and it runs the risk of missing much of the depth, texture, and complexity of bronze age life. the fol- lowing comments are based on many years of work on the british bronze age, but are relevant, i believe, for other areas of europe too. it is true, of course, that burials accompanied by swords and other weaponry are a feature of many regions, but there are other sorts of grave groups that provide equally interesting, and often rather different, insights into bronze age society. in particular, there is a danger that, by focusing on warrior burials and accoutrements, we may inadvertently con- struct an androcentric vision of the period: in common with treherne, recent work on the role of warriors and warfare in the bronze age (e.g. kristiansen & larsson, ; harding, ) assumes that posi- tions of social, political, and economic power were held solely by men, and that women were (like fine weaponry) the objects of elite exchange rather than social agents in their own right. there is, of course, copious evidence to counter such assumptions. ‘wealthy’ female burials are found in many regions: the cremation burial of an adult female from the early bronze age cemetery at barrow hills, oxfordshire, was accompanied by a bronze awl, knife-dagger, and necklace of amber, faience, and jet/shale (barclay & halpin, : – ), while the adult female from the famous barrow of borum eshøj on jutland was buried with a dagger, a fibula, an elaborately-decorated belt disc, a neck-ring, two arm rings, two spiral finger rings, and two small bronze tutuli, among other things (glob, : – ). our frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core tendency to sideline this evidence, or to interpret it as an indication that women acted as ‘vehicles for the display of their husband’s resources’ (shennan, : ), is primarily a reflection of the position of women in our own recent past and can be critiqued on theoretical grounds: post- enlightenment understandings of the self construct men as active subjects and women as passive objects, but this is part of an ideology that served particular purposes in the eighteenth and nineteenth centuries, facilitating the colonial endeavour, for example, by feminizing and commodifying landscape. treherne argues that bronze age mor- tuary practices worked to construct an image of bodily perfection for the individ- ual—the warrior’s beauty, as he puts it. yet, this emphasis on the individual, and the assumption that the integrity of the body was a key concern during this period, are problematic, for they impose onto the past a model of the self that is particular to the contemporary western world. body image is a matter of enormous concern in euro-american society today, and the ideological primacy of the individual means that the body and the self are viewed as coterminous, one mapping neatly onto the other, and both having well-defined and impermeable boundaries. there is much to suggest, however, that bronze age concepts of the person were very different. mortuary practices in britain often involve the deliberate frag- mentation of the body. this is true even for those funerary traditions most com- monly invoked as evidence for an increas- ing concern with the ‘individual’, for example beaker burials of the chalcolithic and early bronze age. the grave of the ‘boscombe bowmen’, for example, con- tained the incomplete remains of several adults and children (mckinley, : – ): the articulated adult male (burial ) was missing his left hand and forearm, while the two bundles of disarti- culated bone found just above and below this burial comprise selected skeletal ele- ments from five other individuals, pre- dominantly skull and longbone fragments from the left side of the body. cremation burials are characteristic of the later bronze age in the same region, and the majority of these comprise only a portion of the remains of the deceased. the three heaviest of the twenty-one urned adult cremation burials found at coneygre farm in nottinghamshire weighed g, g, and g respectively, but the remain- ing eighteen burials weighed less than g, and fourteen of these were under g (allen et al., : table ). the evidence for the deliberate destruction of grave goods (brück, , ) and the circulation of heirlooms (themselves often incomplete or composite objects: sheridan & davis, ; woodward, ) indi- cates that objects were subject to practices of fragmentation and curation, and we can suggest that human bodies may have been treated in similar ways: the resulting ele- ments were exchanged over space and time to mark, mediate, and transform inter-personal relationships. such practices hint at relational or dividual concepts of the self very different from modern western ideologies of the individual (see strathern, ; busby, ). an interest in ancestral ‘relics’ perhaps explains the evidence for the reopening of burials and for the reordering of the bones encountered when graves were reused. the early bronze age shaft grave at south dumpton down in kent contained a sequence of burials (perkins, nd); each time a body was placed in the grave, the skull of the previous interment was removed. evidence for the reopening of graves on the continent has often been interpreted as ‘grave robbing’, but could equally have acted as a means of acquiring the bodily remains or objects associated european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core with known and important deceased members of the community. the middle bronze age cremation graves at pitten, in austria, were provided with special ‘doorway’ structures that allowed mourners to access the grave: it has been suggested that their purpose was to allow food offer- ings to be given to the deceased over a protracted period of time (sørensen & rebay-salisbury, : – ), but they may also have allowed grave goods or quantities of cremated bone to be removed. certainly, cremation burials in continental europe sometimes contain only portions of the bodies of the deceased: the urn from grave in area of the late bronze age cemetery at niederkaina in eastern saxony, for example, contained just g of burnt bone belonging to an adult (coblenz & nebelsick, : ). because my own research specialism is the british bronze age, i do not have a clear sense of how prevalent such practices were on the continent, although this is certainly a question that would be worth exploring. in britain, the deliberate deposition of fragments of human bone in domestic contexts (for example, in pits or postholes at the entrance to settlements: brück, ) provides some insight into the ‘afterlives’ of such relics. usually, such finds comprise single fragments of skull or longbone, although the complete mummi- fied ‘body’ of an adult male buried under the floor of roundhouse at cladh hallan in scotland was composed of the skull and cervical vertebrae from one indi- vidual, the mandible of a second, and the postcranial bones of a third (parker pearson et al., ), all several centuries old on burial, suggesting a protracted and complex phase of post-mortem manipula- tion. together, what such practices indi- cate is that the identity of the deceased was not considered fixed on burial but could in fact be reworked as and when fragments of bodies and associated objects were removed, exchanged, inherited, and (re)combined in a variety of mortuary and non-mortuary contexts. treherne’s argu- ment that there was a finality to the moment of burial resulting in the creation of a fixed image of the deceased can there- fore be called into question: instead, memory was created through practices that involved the reworking and recontextuali- zation of fragments of the dead. in addition, it is of course problematic to assume that grave goods were owned by the deceased and reference intrinsic per- sonal attributes (brück, ). grave goods may not have functioned as objects of display, but may instead have described aspects of the relationship between the living and the dead, or ideas about death and the afterlife. although it is often assumed that cremation burials accompan- ied by razors must be male, in fact such items may be the product of ritual prac- tices enacted as part of the funerary rite. toilet articles such as razors, tweezers, and awls may have been used to mark the bodies of the mourners, for example by shaving the hair (woodward, : ). this would have helped to distinguish dif- ferent phases of the mortuary rite, particu- larly periods of separation or liminality. objects such as wagons reference connect- ivity, travel, and transformation, while drinking cups are as much about com- mensality and the consumption of sub- stances that facilitated communication with the otherworld, as personal status. across much of western europe, swords are found not in burials but were instead deposited in rivers (e.g. fontijn, ), sometimes complete and still usable, and sometimes deliberately decommissioned— bent and broken in ways that cannot simply be explained as a product of combat damage. often, large numbers of swords and other bladed weapons are found at particular locations, for example frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core fording places or the confluences of rivers. such finds hint at the fluidity of personal identity for they suggest that the role of the warrior may have related only to a par- ticular phase in the lifecourse, or may have been a temporary and highly ritualized form of identity that was taken up in par- ticular political contexts and subsequently relinquished (fontijn, ). the depos- ition of quantities of metalwork in rivers and their separation from the bodies of particular individuals hints at collective or community identities tied to place, with the character of the objects (weapons made of metal) referencing the dangerous and transformative properties of social and political boundaries. yet, the relative paucity of defended settlements in these regions suggests that other concerns occu- pied those same ‘warriors’ for much of their daily lives. there is, therefore, much to suggest that bronze age models of the self were very different from those common in our own cultural context. if we call anachron- istic ideas about the individual, subjectiv- ity, and the body into question, we must surely also revisit our assumptions about gendered identity: both women and men were actively involved in the construction of bronze age lifeworlds—lifeworlds that involved fluid and contextually-specific concepts of identity and power, and where inter-personal violence was just one element of a complex range of social relationships. comments on paul treherne’s ‘the warrior’s beauty’: the masculine body and self-identity in bronze age europe katharina rebay-salisbury twenty-one years after its publication in , paul treherne’s ‘the warrior’s beauty’ remains an influential article for scholars interested in the archaeology of the body, gender, and identity in later european prehistory. the archaeology of the body and identity has since developed and grown, becoming a popular field of study in many different regional archaeol- ogies (e.g. meskell, ; hamilakis et al., ; joyce, ; robb & harris, ). this article, originally conceived as an mphil dissertation at the university of cambridge, investigates how the identity of the european bronze age warrior emerged from practices and beliefs cen- tring on the human body and its aesthetics. treherne presents warrior identities as a pan-european phenomenon and an import- ant part of europe’s long-term social fabric. first formulated in the bronze age, a spe- cific way of making identity continues into the iron age and beyond well into the middle ages. the warrior lives a particular lifestyle, which includes war/warfare, alcohol, riding/driving, and bodily orna- mentation (treherne, : , hereafter only page numbers cited); in death, these themes are further developed and become archaeologically visible in burial practices and grave goods. the ‘warrior package’ thus contains several elements, which include personal weaponry, drinking equipment, bodily ornamentation, grooming tools, and horse harness and/or wheeled vehicles (p. ). among the archaeological evidence, treherne scrutinizes toilet articles such as combs, tweezers, razors, mirrors, and tat- tooing awls in particular. male self-iden- tity, according to treherne, is linked to a specific kind of masculine beauty and achieved through bodily regimes. treherne’s study is unique in that it aims to integrate the concepts of beauty and aesthetics into the large body of literature on bronze age war, warfare, and violence. to the modern reader, the catchy and intriguing title of treherne’s article european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core provokes an association of dissonance: beauty is a concept that tends to be asso- ciated with femininity rather than mascu- linity today. the notion of the beauty of the warrior seems at odds with that of beauty. bodily beauty and physical attract- iveness, however, are important for both sexes, although what is considered beautiful is different for men and women; it under- lies evolutionary principles of sexual selec- tion and connotes health, symmetry, and sexual dimorphism (grammer et al., ). further, treherne’s is one of the few articles that explicitly thematize masculin- ity, not only theoretically (as knapp, has done admirably), but using archaeo- logical evidence constructively to paint a vivid picture of what a particular kind of male identity might have been like. as such, he fulfils the call for understanding the warrior identity as one of ‘divergent, multiple masculinities’ (p. ). the development of a warrior ideology is tied into two large-scale social shifts in later european prehistory. the first con- cerns a shift from an ideology of place and community in late neolithic/copper age societies to an ideology of individual and personal display, which characterizes bronze age societies (p. ). this shift took place at different times in different places, notably in a first wave during the fourth and third millennium bc (asso- ciated, for example, with bell beakers). burial in communal, megalithic tombs gives way to funerary rites that include the interment of a single body in an individual grave, with personal grave goods including prestige goods acquired through long-term exchange networks. social categorization, including gender and status, was achieved and played out in elaborate funerary rituals, but they were fleeting events: as the body was only visible for a very short time, it had to be represented in a very for- malized and stereotyped way to communi- cate the message of identity unambiguously, ‘fixing an image of the deceased’ in the memory of the participants in the funeral (p. ). a second wave of ideological change began in the mid-second millennium bc (associated with the central european middle bronze age) and intensified towards the iron age: a ‘differentiated warrior ideology’ devel- oped from a ‘generalised male ethos’ (p. ). traditionally, this has been interpreted in terms of increasing social hierarchies and the rise of chiefdoms. importantly, the warrior identity now includes membership in a spe- cialized group, attached to a patron in para- mount position. warriors engage in a system of relationships of hospitality and reciprocity, which includes exchange, the consumption of alcohol, a shared belief system, shared daily life, and ritualized warfare (p. ), accom- panied by cultural emotions such as honour (see péristiany, ). archaeological evidence of this change include the sword—the first object designed solely for combat—among other weaponry and sets of drinking vessels which go beyond meeting an individual’s needs, ornaments that ‘accentuate every part of the body and its movement’ (p. , a theme further developed by sørensen, , ), and an emphasis on textiles as well as ‘toilet articles’. toilet articles are artefacts specifically designed for bodily grooming and decorat- ing, such as combs, tweezers, razors, mirrors, and tattooing awls. shaving, combing, plucking hair, manicuring nails, scarification, and tattooing are argued to be part of the daily routine of taking care of the body. like weapons, toilet articles show signs of wear and tear, which sug- gests they were used to achieve ‘beauty in life’. bog bodies with exquisitely mani- cured hands, which requires attention over extended periods of time, attest to daily self-care. further evidence comes from bronze age anthropomorphic representa- tions with carefully shaved and groomed frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core hair. the aesthetics of the warrior were achieved through reflexive, personal action; they were important in life and death, ‘mutually constituting one another and together the individual’s self-identity’ (p. ). toilet articles might have also played a role in specific rituals for particu- lar occasions, e.g. before entering battle or during funerary activities; the fact that they were placed around the body in the grave points to their use in the preparation of the corpse or in ritual mourning. at this point, i have always wondered why treherne did not develop this argu- ment one small step further: namely, to see toilet items as means of identity trans- formation. by employing bodily rituals such as shaving, cutting, and grooming hair, the transition between different kinds of male identity—perhaps that of the warrior and that of a more civil nature— could have been marked and achieved. multiple masculinities may have had dif- ferent appearances. the warrior identity would then appear less fixed, although perhaps bound to a certain age and status group or group membership, and more fluid, situational, and temporal. the warrior identity could have been taken up on particular occasions by different people, at times perhaps even by women. interestingly, the discussion of beauty is centred on hair and nails, and there is little discussion of other bodily constitu- ents of beauty. for the warrior especially, attractive body proportions with a lean body mass and well trained and defined muscles would have certainly been the ideal, and could only be achieved through regular training. bronze and iron age body cuirasses (e.g. from kleinklein, austria: egg & kramer, ) with hints of muscle lines are indicators of such beauty standards. treherne’s article develops theoretical thoughts on transformations of ideology and the emergence of elites. he reacts against the prevailing interpretation of the focus on the human body in the grave as a medium of ideological expression, with the grave as the arena of power negotiation and the ‘ideology of prestige display’ employed in legitimization through mysti- fication. the mantra of funerary archaeol- ogists at the time—that the ‘dead do not bury themselves’ (see parker pearson, : )—had begun to disregard and overshadow the lives of the buried people. drawing on materialist formulations of ideology, tension between ideology as illu- sion and social reality had emerged. treherne, however, insists that people lived their ideology as real (p. ). grave goods chosen for display and conspicu- ous consumption as well as ostentatious funerary rituals are expressions of social practices and beliefs people actually sub- scribed to. to explain why specific objects are selected for social legitimiza- tion and aggrandizement, their specific socio-historic context has to be taken into account. formulating his own philosophical pos- ition on the body against the work of althusser, merleau-ponty, bourdieu, giddens, and others, treherne stresses the ‘fundamental materiality of the body and self’ (p. ). the body is more than a social construct, a product of discourse or the symbolic; the self is practically mediated and lived through the body. self-identity emerges through sensory exploration with the body as the medium of experience; self-care and beauty main- tenance, therefore, play an important part in identity construction. to explain why beauty was important to the bronze age warrior, treherne draws on sources and scholarship on the heroes of greek antiquity (e.g. vernant & zeitlin, ; shanks, ). in particular the (lack of) beliefs in a life after death meant that the self could only transcend death in the minds of the living (p. ). european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core fixing the image of the deceased in the mortuary sphere was therefore paramount, because only memory preserved the deceased in the social discourse (p. ). the emphasis on beauty counteracted the notions of mutilation, dismemberment, and decay associated with the corpse; elab- orate funerary practices helped to cope with the emotion of existential anxiety and counteracted forgetting. these notions are not necessarily appar- ent from the archaeological evidence alone and they raise questions about the applic- ability of the concept of the ‘warrior’s beauty’. treherne’s focus on a detailed interpretation of the warrior identity led him to neglect temporal and regional dif- ferences; and the extent of the phenom- enon remains vaguely defined. treherne traces roots in the emerging urban soci- eties of the near east and anatolia (p. ), from which elements were select- ively adapted; a part of the ideological transformation towards an emphasis on the individual seems anchored in northern and western europe (although other forms of personhood than the individual may have prevailed; see fowler, ) and does not fit central and eastern europe in my opinion, where single graves have a much longer pedigree. cemeteries with individ- ual graves and personal grave goods were already common forms of body disposal during the lbk (linearbandkeramik, c. – ). subsequently, the depos- ition of ‘multiple and fragmented bodies’ in cairns, passage graves, and other mega- lithic structures became popular from scandinavia to iberia (hofmann & whittle, : ), but remained a northern and western european phenomenon. the ‘differentiated warrior ideology’, in contrast, has perhaps most archaeological support in central europe, where social dif- ference became expressed through burial practices and grave goods since the early second millennium bc at the latest (examples include the ‘princely graves’ from leubingen and helmsdorf, germany; meller, : ). treherne, however, seeks interpretative analogies in much later greece. and although the warrior identity is discussed as a historically situated product of time and place (joyce, : ), one wonders if the combination of groups of males engaging in violence, intoxication, and beautification is not indeed a cross- cultural phenomenon. specific to the european bronze age are then merely the burial practices and the specific kind of prestige good economy tied into metal circulation. it further remains unclear how broadly the concept of the ‘warrior’s beauty’ applies within a given society. does the ethos of the warrior form part of the general social ideology, adopted by every male of a certain age group, or how select- ive was membership in the warrior society? treherne laid out how elite warriors had a lifestyle that involved risk and violence, but also of luxury and excess, apparent in valuable weaponry and bodily grooming, and with it a worldly existence of honour, glory, and beauty to be remembered so as to transcend death. however, what about the common fighter? the family father defending his farmstead, the youth gang raiding the neighbouring village, the mer- cenaries, and those forced to fight for others’ causes? it seems that the bronze age elite warrior was similarly removed from those fighters as the officer in command is remote from the common soldier today, who, through discipline, control, and sub- ordination, emerges as a non-individual (p. ). the unknown, anonymous soldier encompasses all nuances ranging from the operator of a killing drone to the injured and traumatized homecoming hero. perhaps it is time to shed light on the diversity of fighters in later european prehistory, too. frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core the nature of warfare and violence and its associated archaeological evidence in the form of weaponry, defensive architec- ture, and trauma on human remains has not lost its appeal since the publication of treherne’s article (e.g. osgood & monks, ; parker pearson & thorpe, ; otto et al., ; peter-röcher, ; uckelmann & mödlinger, ). krieg, the current exhibition at the landesmuseum für vorgeschichte in halle (saale), traces the origins of war in the neolithic (meller & schefzik, ). anthony harding perhaps best described the chronological and regional variations in the evidence for fighting. he found the characterization of bronze age warriors as a war-band engaging in inter-group raiding more to the point (harding, : ), although he too maintained the existence of an encompassing ideology of honour, prestige, and violence. kristian kristiansen and thomas larsson ( ), as well as richard harrison ( ), stressed the religious and ritual role of the warrior. a persuasive interpretation of bronze age religion on the basis of the iconography on razors has been put forward by flemming kaul ( ). the idea that the warrior’s self-identity was connected to the maintenance of bodily ideas, however, was nowhere else formu- lated as concisely as in treherne’s article— it seems to have stood the test of time. warrior’s beauty: revisited from a nordic perspective sophie bergerbrant paul treherne’s article ‘the warrior’s beauty’ was published in the journal of european archaeology twenty-one years ago ( ); it remains the most downloaded article in the history of the european journal of archaeology. the article was a reworked version of his mphil dissertation submitted to the university of cambridge. in it he argued for the need to revitalize and revise the concept of the ‘warrior aristocracy’ (kriegeradel in german). the article thus redefined the warrior ideal, both in life and in death. treherne emphasized tan- gible, personal consumables that were essential for identifying this developing status group, and these centred around four important themes: weaponry, drink- ing equipment, bodily ornamentation (toilet articles), and horse harnesses and/or wheeled vehicles. he pointed out that not all attributes were present in all cases of warrior graves, and that a distinct form of masculinity, which was present both in life and in death, was central to the warrior ideological complex. he argued that a warrior ideal and lifestyle was born in or around the bronze age and that it endured for an extended period in history. treherne’s contribution was an import- ant catalyst for reviving the topic of the warrior class and ideal in history. many studies have followed since (vandkilde, a: ), and treherne’s article can be seen as having had a significant role in this revival. indeed, it has been one of the inspirations and starting points for numer- ous studies about prehistoric masculinity. it has also been referred to in many sub- sequent scandinavian studies (e.g. my own phd: bergerbrant, ), and in studies about warrior graves (e.g. sarauw, ) and warrior identity (e.g. skogstrand, ). however, the article’s emphasis on the longevity of the warrior ideals has, in many ways, led the notion that ‘warrior identity’ was a monolithic cultural norm through many periods and regions, effacing subtle variations and culturally specific views of warriors. for example, skogstrand ( : – ) has shown that warriors disappear from the archaeological record on funen in the early pre-roman iron age; and, when they reappear, in the late pre-roman iron age, the warrior role has profoundly changed european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core from the late bronze age form described by treherne. despite this, treherne’s con- tribution provided a key to opening up new angles for the study of masculinity, although explorations of gender and masculinity are unlikely to have been the conscious or primary aims of the author as it is largely grounded in a different body of theory from most gender and masculinity studies. it also has quite a narrow focus, with the warrior class being treated as the only male identity worth defining, while today we are more likely to acknowledge the permutations and variations of masculinity (e.g. skogstrand, ). indeed, a close study of the male costumes recovered from the anaerobically preserved danish oak log coffin burials has shown that there are at least two, and probably more, variations in male gendered attire, only one of which could be related to warriors (bergerbrant, : – ; bergerbrant et al., ). as the title indicates, treherne’s article focuses on appearance and the beauty of the warrior, the softer and aristocratic side of warriorhood: the flashy weapons, the horse riding/chariots, the drinking, and the grooming. these are the positive sides that create bonds between males. although it also claims to touch upon the darker sides of warriorhood, it really only mentions the actual hardship of a warrior lifestyle, i.e. war, and even that gets only a brief mention. lately, remains of large- scale warfare have been excavated in nor- thern europe, such as at tollense for the bronze age (jantzen et al., ) and alken enge for the iron age (holst, ), both showing the more brutal and unsavoury side of warfare. the tollense publication, for example, demonstrates that many of individuals who died in the battle and ended up in the river were non- locals, and the evidence for their diet indi- cates that they had been eating millet (jantzen et al., ), a plant that did not normally form part of the local diet. the site indicates that warriors travelled long distances, and many died as a result of warfare, as demonstrated by the examples of arrowheads found embedded in skulls (jantzen et al., ). of course, one could always discuss whether these indivi- duals were part of the warrior aristocracy or whether they were ‘mere’ foot soldiers. the first publication about tollense focuses on the actual remains of warfare found at the site, and, not surprisingly, there is no reference to treherne’s article in the book (jantzen et al., ). the main focus in treherne’s article is the theoretical perspective it puts forward, with the archaeological material being included mainly as an illustration of the idea. the author emphasizes the import- ance not of a beautiful death as much as that of a beautiful treatment after death and in burial and hints that the presence of beauty in the burial might have been a way to cope with the anxiety that may have arisen after a warrior’s death. drawing on the evidence that swords have been reshaped and toilet-equipment used, he suggested that ‘beauty’ was a fundamental part of the warrior lifestyle, too. even though the body of the warrior is inter- preted as an important part of the self- identity of the warrior aristocracy, the body of the warriors, the skeletal remains, are not brought into the argumentation. bodies are often an important archaeological source for obtaining information and knowledge about prehistoric warfare. in the routledge handbook of the bioarchaeology of human conflict (knüsel & smith, a) there are no references to treherne’s article either, whereas in the oxford handbook of the european bronze age (fokkens & harding, ) a number of articles refer to it. the physical sides of warfare and warriorhood need to meet the identity and status side put forward by treherne. the challenge for the future is to combine these different aspects of warriors in prehistory, and to tell frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core a more complete story as there are always two sides to a coin (see knüsel, this section). over the last ten years there has been a growing interest in the archaeology of the body in research (e.g. sofaer, ; boric ́ & robb, ). many of these studies have shown the importance of connecting the physical body with archaeological interpretations of identity, in line with some of treherne’s arguments. not only have there been theoretical developments concerning the archaeology of the body, there has also been great progress in scien- tific analyses that can help us gain informa- tion about the body. new developments in isotopic analyses and adna have given us new and unique possibilities for investigat- ing the diet, mobility, and genetic heritage of deceased individuals, warriors or not, at a much more detailed level than ever before. so far, the most in-depth studies of this kind have been conducted on female graves (e.g. the new analysis of the egtved girl by frei et al., ), but future work on warriors’ graves would clearly expand our understanding of warriorhood in the bronze age. an increase in the number of experimental warfare studies has also taken place over the last decade. all these recent developments need to be viewed together for an up-to-date reassessment on the bronze age warrior. we might not need to revitalize the archaeology of warfare and warriors, as treherne’s article did twenty- one years ago, but all this new research demands another serious theoretical and methodological discussion to bring together and reassess the different dimensions of warriorhood, both the beauty and the beast. it is easy to find flaws in an article written two decades ago. the intention here is not to belittle treherne’s article in any way. it was, and remains, a sound and influential text, and it has been an import- ant article for many fields of archaeology. as has been noted above, this article was significant for changing perspectives and redirecting research on warfare and war- riors. however, twenty-one years later its contribution and role has changed from being a new and innovative article to being ‘a classic’; a starting point for many fields of research. it set a new baseline upon which we continue to build. the problem is, are we not becoming lazy if we simply go on accepting this article’s inter- pretation as the norm? the time has come for another young scholar to write a new thought-provoking article with a fresh interpretation on warfare and warriors in order for research to move another step forward, an article that embraces the multitude of ideas and data available through new theoretical and methodological developments within the archaeology of the body, or body-centred archaeology, without forgetting the many important contributions highlighted by treherne. we should never forget that the beauty of the warrior ideal is always fol- lowed by the threat and unpleasantness of warfare. i hope there is someone out there who might be up to the task of again writing an article that challenges our per- ceptions so profoundly that it shifts and changes the course of many fields of archaeology. an iberian perspective on ‘the warrior’s beauty’ sandra montón subías twenty-one years ago, in his now classic article under discussion here, paul treherne brought to the fore the analysis of subjectivity in understanding what hap- pened in the prehistory of europe. after reviewing the evidence for warriors and warfare, he rejected as ‘deficient’ the ideology-as-a-resource mainstream inter- pretive models for the neolithic/bronze age transition, and re-evaluated this shift european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core in terms of changes in the construction of the male self. in so doing, he pioneered studies of masculinity, of embodiment and symmetrical analysis in archaeology. in addition, his work remains a fine example of the role that prehistory can play in the construction of world history. contrary to the quite common convic- tion that interest in warfare and warriors is mainly a product of the s, i regard the subject as deeply ingrained in the fabric of archaeology. indeed, the emer- gence of militant male warrior elites has been considered inherent to processes of growing social complexity since the begin- ning of our discipline (see siret & siret, as an early example from iberia). although frequently theoretically under- developed, concepts such as warriors, con- flict, instability, warfare, and militarism have been widely used in the archaeo- logical literature of all time. poorly devel- oped theorizing is, in my view, not so much related to a lack of interest or a con- scious wish to pacify the past (as stated, for instance, by keeley, ), but to the very idiosyncrasy of archaeological schools of thought and background assumptions that have taken the phenomenon for granted (see aranda jiménez et al., as an example, again from iberia). within culture history, for instance, the theme was ubiquitous in the form of studies of weaponry (especially typologies), which were and are widely used as fossil types to define and characterize cul- tures, and to construct temporalities and chronological sequences across the whole of europe. from the s onwards, growing attention (from heterogeneous perspectives too) to the evolution of social complexity during the transition from the neolithic to the bronze age also corre- lated the increase in social hierarchy with the rise and consolidation of a male body of warriors. treherne drew on the same material evidence handled by these previous studies (new specialized weap- onry, horse harness, wheeled vehicles, ornaments, and grooming tools) and accepted them as proof of new war-like practices and body language. however, he rejected the modernist dualistic thinking that took these shifts to merely represent a change ‘from an ideology of place and community to one of the individual and personal display’ (treherne, : , hereafter cited by page number only). to him, the neolithic/bronze age transition was, first and foremost, an ontological process. ‘the warrior’s beauty’ connected the emergence of individualization and per- sonal display in the archaeological record with a new style of life and changes in what it was to be a person (p. ) and, more specifically, in male self-identity (p. ). warrior paraphernalia did not, thus, allude to a restricted elite mobilizing ideology as an external resource for its own benefit—as if persons and ideology belonged to different plans of action, as ideology could embrace structured thoughts detached from people’s actions—but to new men’s embodied understandings of themselves, their identity, and their way of being in their surrounding world. having set out the outline of treherne’s argument, i would like to point out how valuable i find the identification of general trends in prehistory that may be related to concerns of our current times, without doubt a clear merit of treherne’s overview. maybe because i teach an mphil course on world history and most of my depart- mental colleagues are historians of the written sources, i have for some time insisted on how important prehistory is in the construction (and teaching) of world history. perceived sometimes as a remote (and even exotic) domain, it is also often thought to be unrelated to problems of the present day. however, prehistory saw the birth of many different processes that have frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core moulded the world to its actual shape. the fact that present social and gender inequality, existing identities and ways of being a person, and cultural values and attitudes have been formed by complex long-standing processes beginning in pre- history, and that these can only be well understood and modified in light of their historical backgrounds, has been insuffi- ciently explored. i find it worrisome, however, that long- term reviews are usually constructed to enhance social change(s) at the cost of social continuity(ies). because i find treherne’s contribution to fit this tendency, i will now focus in greater detail on his main subject: the emergence of individuality in wide- spread areas of europe. my intention here is to discuss the article on its own terms and not so much to point out missing topics that fall outside treherne’s purpose. fundamental to the author’s argument is the relationship between material culture, the body, and the new type of subjectivity incarnated in the male warrior. according to treherne, previous works had not really grasped the reasons why objects designated as ‘prestige items’ (an expression that he considers reductionist) are those and not others. mainly consid- ered as signs of elevated status, their intri- cate and vital relationship with the manipulation of the warrior’s body had remained unattended. pioneering symmet- rical archaeology, treherne claims that these goods are not only expressing but also constructing a new ‘notion of self and personhood, grounded in changing atti- tudes to and practices in, on, and through the body’ (p. ). however, to me, the importance of the body is more announced by treherne than it is explained. even when, inspired by works about the homeric warrior, he assumes the centrality of the body in societies with no body/ mind dichotomies, the reader may remain mystified by why the body is so paramount in constructing individualization and dif- ferentiation. at this point, i would like to draw attention to a series of works that have contextualized the importance of the body for personhood construction in the framework of oral societies (especially hernando, , ; moragón, ). drawing also on the absence of the body/mind dichotomies and on studies promoted (among others) by norbert elias, walter j. ong, and david r. olson, such works have explained that, in prehis- toric oral societies, there must have been no disconnect between what persons were and their bodies, no fracture between what persons thought they were and what they actually were. persons became selves through their embodied actions. under such circumstances, the body was precisely the main mechanism (instead of abstract thinking and reflection) to construct and manifest identity (through its management, movements, actions, and associated material culture). in this sense, the importance of the body in self-hood construction was nothing new to bronze age europe. however, while community belonging was previously performed, bronze age warriors set themselves apart and emphasized differ- ence. the difference was thus between being a part of and being apart from, but always through the body. however, and here i refer again to the change versus continuity issue mentioned before, it is not possible to be apart from something without at the same time being a part of it, as almudena hernando has shown in her works. while most scholar- ship has read bronze age warrior’s gear, she argues, in terms of individuality and difference, it has at the same time ignored its meaning regarding relational bonding. while warriors were setting themselves apart, they were simultaneously bonding with new peers (warrior fraternities), and thus maintaining, although in a new fashion, relational identity (hernando, european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core : – ). treherne thus ignores relational mechanisms that remained in the construction of the new subjectivity. in this sense, we could say that treherne’s is a masculinist study on masculinity. in focusing only on individuality and social change, he is stressing values that define hegemonic masculinity in the present and dominate the mainstream writing of (pre) history (see on this issue hernando, and montón subías & lozano, ). in mentioning these flaws (in my view) i would not like to diminish the article’s merits. i regard it as a fundamental piece in archaeology’s literature, not surprisingly ‘the most downloaded paper in the entire eja archive’, as catherine frieman men- tioned when she invited me to contribute here. paul treherne is among the first scholars explicitly reflecting on the con- struction of the male self in prehistory. in the s, when gender studies in archae- ology were mainly perceived as women’s affair, it was very important to reflect on the fact that men also had gender. in add- ition, treherne’s article made very clear that, during prehistory, there were differ- ent ways of being a person and, import- antly, that individuality had a (pre)historic starting point. that is beyond any doubt, and as such needs to be acknowledged. i want to insist, however, on how import- ant it is to complement overviews such as treherne’s with studies of social dynamics, values, and principles that have been mar- ginalized from the mainstream of scholarly discourse and thus left outside history. to continue with examples from iberia, differ- ent works—from a feminist or feminist sen- sitive standpoint—have already attempted to redress imbalances created by this neglect, focusing on the role of stability, continuity, recurrence, relationality, and interdepend- ence (see, also for the bronze age, colomer et al., and aranda jiménez, as two examples). only by considering the interplay between change and permanence can social complexity and diversity in the past be comprehended, changes be under- stood in their full dimension, and an inclu- sive world (pre)history be constructed. it is not only a question of fairness or representa- tion; it is a question of improving archaeo- logical and historical knowledge. the warrior’s seduction joanna sofaer in his novel the narrow road to the deep north, richard flanagan describes the atti- tude to virtue of his central character, war hero dorrigo evans: ‘dorrigo evans hated virtue, hated virtue being admired, hated people who pretended he had virtue or pretended to virtue them- selves. and the more he was accused of virtue as he grew older, the more he hated it. he did not believe in virtue. virtue was vanity dressed up and waiting for applause.’ (flanagan, : ) virtue, then, is not a matter of self-identity, which, as dorrigo evans’s story unfolds, is full of complexity and doubt borne of self- knowledge and introspection. instead, virtue in relation to self does not really exist, or at most is shallow and showy. it emerges primarily from the desire of people to attribute qualities to others as if to give themselves hope in a world where honour and heroism seem in short supply. as i write, the news is full of refugees fleeing conflict, stories of soldiers suffering from post-traumatic stress disorder, and terrorist atrocities. perhaps it is precisely because of the lack of virtue in the modern world that the romantic vision of a warrior golden age offered by treherne is so appealing. yet it is both striking and dis- turbing that the combination of heroic traits identified by treherne—a focus on hair and grooming as a marker of identity frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core and lifestyle, the search for glory, eternal remembrance, and heroic death—are hall- marks of a range of modern military and terrorist groups, albeit in different ways. one thinks of the ‘buzz-cut’ in the us military, the immaculately groomed and uniformed soldiers of the north korean regime, and the propaganda promulgated by the self-styled warriors of daesh. in each of these cases, the individual male body is linked to the body politic (brod & kaufman, : ). there seems very little of beauty here. i do not doubt the importance of social categories in the bronze age, that ‘the warrior’ may have been one such category, or that the body, its display, and adorn- ment played a significant role in the medi- ation of bronze age social relations. however, ‘the warrior’s beauty’ proffers a highly sanitized and hegemonic view of bronze age masculinity that does little justice to the complexity of human identity (see cornwall & lindisfarne, ). asserting that there was a ‘coherent warrior lifestyle’ does not mean that all eli- gible men conformed to it. the evidence for how regularly masculine ideals were enacted and sustained, or how individuals entered the warrior ‘class’ is thin—to what extent was it ‘action-based’ or inherited? similarly, the extent to which warrior values can be exclusively equated with social status, or whether status might be expressed or achieved in a variety of other ways, is unclear. one might also ask to whom the performance of beauty was directed and whether it took place in public or in private. in an age before mirrors, did men groom themselves or was this done for them? in the case of the latter, was identity, therefore, a co-cre- ation? how might modifications to the body aim to meet the expectations of others rather than of self? furthermore, the homeric epic poems (a key strand in treherne’s argument) post-date the bronze age (finkelberg, ). thus, they cannot be understood to represent a bronze age reality, but are likely to represent an amalgam (snodgrass, ) or ‘unhistorical composite’ relevant to the values of the intended audience (osborne, : ). yet these unresolved ques- tions, tensions, and deficiencies often seem to be willingly overlooked, such is the draw of treherne’s narrative. ‘the warrior’s beauty’ remains one of the few unambiguous discussions of mascu- line identity in the prehistory literature and here, too, lies some of its allure. it is useful to recognize that the article was written in the early days of gender archaeology. the potential of mortuary contexts for gendered analyses in terms of the relationship between the physical body and grave goods had recently been highlighted in a range of publications (e.g. bertelsen et al., ; gero & conkey, ; see also sofaer & sørensen, ). while these and many other subsequent works aimed to rectify the ‘invisibility’ of women and other social groups, on the whole men have remained visible but ‘unmarked’ (alberti, : ). treherne’s article, therefore, offers a form of analysis that remains largely unavailable elsewhere. it may also provide a potential point of self-identification for modern men, something noticeable in responses to ‘the warrior’s beauty’ in my own teaching prac- tice: a delight (and relief) that the study of social identity and gender has a place for men and is not just about women! however, whether the enduring popularity of the article is due to the particular nature of the insights it provides into the bronze age and the nature of masculinity, or whether it results from disciplinary failure to develop a range of recognizable narra- tives about men (and thus a lack of alterna- tive points of contact with the past for young men in particular), is unclear. in claiming that the origins of feudalism lie with the bronze age warrior, treherne european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core positions the bronze age in a particular way with regard to the construction of modernity and creates a seductive legacy for modern masculine identity. however, this apparent legacy deserves scrutiny since the elision of two distant and entirely different periods is awkward. there is, therefore, potential for a vibrant, more contextually- specific discussion that enriches archaeology by recognizing dynamics, complexity, and nuances in the interwoven histories of women and men. though presented through the lens of theoretical debates surrounding various marxist and post-processualist understand- ings of the expression of ideology that took root in the s and s, much of the article reads as if it could have been written more recently. re-reading ‘the warrior’s beauty’ twenty-one years after its publica- tion, it is striking how current some of the terminology is. terms such as ‘embodi- ment’, ‘performance’, ‘subjectivity’, and ‘per- sonhood’, along with an explicit focus on the physicality of the body as a source for the construction and mediation of identity, resonate with contemporary concerns regarding the nature of past human experi- ence. the article, therefore, retains discip- linary relevance, although it is notable that, in contrast to the extended discussion of ideology in the first part of the publication, the theoretical vocabulary that may be of most interest today is comparatively under- referenced and used relatively loosely. a lack of explicit ‘positioning’ in terms of the shades of meaning that accompany some of these theoretical strands may be an add- itional reason for the article’s continuing appeal. in other words, it is easier to agree with generalities rather than specifics. a number of highly relevant volumes arguing both for and against treherne’s position in relation to the body had already been pub- lished prior to , but are not cited by him (e.g. butler, , ; featherstone, ; shilling, ; cornwall & lindisfarne, ; moore, ). it is, therefore, interesting to consider whether the impact and continued relevance of the publication reflects its original aims and intentions. rather than continuing to use the article in order to understand masculine identity, it may be profitable to return to, and critically engage with, treherne’s broader initial goals and arguments regard- ing the lived experience of ideology. today, when it seems that ideology is everywhere, a critical re-reading of treherne’s text has particular poignancy in reflecting upon the potential role of ideology in the develop- ment of human experiences. it challenges us to consider how the expression of indi- vidual and group action is tied to beliefs about the world and one’s place within it. though treherne’s article retains its popularity twenty-one years after its ori- ginal publication, this is not necessarily due to its complete veracity or the bullet- proof nature of its arguments and evidence base. instead, it appeals to the all too human desire for his narrative in our own turbulent world. it speaks to the pressing need for particular kinds of histories and thereby highlights both missed opportun- ities and constructive disciplinary develop- ments. it will doubtless continue to be widely read as new generations of archae- ologists find inspiration in its pages. the ongoing significance of paul treherne’s classic article ‘the warrior’s beauty: the masculine body and self-identity in bronze- age europe’ (journal of european archaeology, ( ), – .) in recognition of the th volume of the european journal of archaeology christopher j. knüsel this review comes in the midst of what has been described as a ‘crisis of masculin- ity’ in societies across the world, a social frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core phenomenon that is characterized by a male attainment deficit, increased incar- ceration and recidivism, poor employment prospects, and low self-esteem. in the economist noted that ‘throughout the world, developed and developing, anti- social behaviour is essentially male. violence, sexual abuse of children, illicit drug use, alcohol misuse, gambling, all are overwhelmingly male activities’. the article goes on to observe that ‘men […] have been robbed of their traditional roles as providers, protectors and even procrea- tors’. nearly fifteen years later, in , the economist characterized this trend in rich countries as ‘no job, no family and no prospects’. this description of contemporary mas- culinity is completely at odds with the image paul treherne paints of masculinity some years ago in ‘the warrior’s beauty’. treherne characterizes these bronze age warriors as epitomized by a concern with physical appearance, as implied by items described as ‘toilet kits’ found in their graves, consisting of combs, razors, and tweezers, which probably groomed them in life and at death. he describes these warriors as ‘beautiful’, adorned in shiny gold and bronze metal- work displayed on woollen garments, with elaborate, well-groomed, and probably dis- tinctive hairstyles and perhaps facial hair or lack thereof. they may have employed make-up, perhaps using the peculiar wooden ‘spatulas’ sometimes found in burials, contemporary examples of which were found with gristhorpe man (melton et al., and see below) and another with the amesbury archer (fitzpatrick, : ). these bronze age men engaged in feats of conviviality—drinking bouts and feasts—and in the skilled use of the first specialized arms requiring both physical co-ordination and more assiduous training. they had personal character and their appearance expressed a developed self-identity based on a weapon-bearing warrior lifestyle. perhaps, like their later medieval counterparts, they evinced prowess; not only physical skill, but bearing and poise in conduct (see knüsel , ) that won glory, renown, and remembrance that formed the goals of life and contributed to a good death (bloch and parry, : ; binski, ) as represented by an elaborate single burial beneath a mound visible for all to see. these men seem to have exuded confi- dence, self-esteem, and self-assurance within their societies, as reflected and represented in the treatment of their bodies in death. treherne draws splen- didly on the notion that ‘the body and its treatment becomes [sic] an artefact of and canvas for symbolic and social expression’ (knüsel et al., : ). although treherne’s article is admirable for highlighting the accoutrements, mater- ial culture, and aspects of the social context of these bronze age warriors, it inspired my interest, in part, because of the areas in which it is least developed. despite repeated mentions and discussion of the body from a metaphysical point of view based on funerary remains, few remains of bodies enter into the piece and when they do they involve apparent manipulations of the remains of the deceased with presumed symbolic value that has more recently been ascribed to other processes in many instances. in effect, this leaves the use of ‘male’ and ‘masculine’ in his treatment in the same realm as the use of the word ‘prestige’ that is critiqued so thoroughly in it. the phys- icality of these warrior males is left untouched—their height, weight, phys- ique, their maladies and wounds, the extent of their masculinity as defined by masculine physical traits—and even if all the individuals accompanied by such objects were indeed males, all of these attributes can be determined from the european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core analysis of the skeletal remains of the deceased. were these men physically dis- tinctive? where did they come from, and to whom were they related? did these physical attributes also have an influence on the appearance and status of the warrior as much as their dress and accou- trements? some of these questions have been answered in the twenty-one years since the article was published, but many have not, and geographic and temporal coverage is uneven. these corporeal attri- butes could act as a complement to, and contribute much, if not more, to the ‘sub- stantive content and implications for sub- jectivity’ (treherne, : , hereafter cited by page number only), to address ‘the relationship between the body and subjectivity’ (italics in the original) implicit in the objects found with the dead. this means that the template provided by treherne could be judged against individ- ual bronze age warrior graves, and it could inspire similar approaches in later periods, as indeed it did in the medieval examples referred to above. deeper consideration of the physical remains of the dead would also contribute to better understand the placement of objects on the body with respect to skeletal remains; this would do much to unravel the ideological underpinnings of these objects, revealing in the process a grammar of symbolic intent present in the pattern- ing of material with respect to the remains of the body. the corporeal attributes of these well- appointed male burials can also provide a means to study the social effects of ideolo- gies that permeate all forms of human practice and whether or not their manifes- tations were indeed a conspiratorial prac- tice of a ‘small group of cynical men’ (p. ) to obtain a pre-eminent social status that conferred membership to ‘the warrior fraternity’ (p. ). as noted by treherne, the societies of the late neolithic and bronze age were not egali- tarian (if not before, see below), and it may well be that the activities and beha- viours linked to the appearance of these individuals was indeed a conspiracy to legitimate social inequality. and this may have been enforced through threat and fear of retribution—from within social groups and from the outside—that led to the hegemony of groups of people, at least in some places and times. the means to explore these relationships come in two forms: measures of well-being and physical injuries, including weapon-related trauma. again, both relate to the physical remains of the deceased. one of the occupants of these bronze age single burials, the nearly complete skeleton known as gristhorpe man, was buried in an oak log coffin on the coast overlooking the north sea, near scarborough in yorkshire (melton, et al., , ). he was buried with a whale- bone-embellished dagger, among other artefacts. gristhorpe man and other single inhumations form a distinctive group of ‘tall men’ from the early bronze age in britain that suggests preferential access to good nutrition and growth environments commensurate with social advantage from birth, stature being a good measure of population and individual health and well- being (see discussion in mckinley, ; knüsel et al., ). these men may have belonged to an inherited social elite for a period of time, though one that was not apparently sustainably inter-generational over the longer term. gristhorpe man was of robust build with an enviable body mass, producing a high normal body mass index by today’s standards. his was of ath- letic build. his strongly developed right dominant arm (i.e. humerus) testifies to its use in strenuous physical activities that are likely to have included technological and subsistence-linked activities such as manu- facture and maintenance of objects, as in frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core woodworking and metalworking, and pur- suits requiring physical effort, including long-distance walking and sport, as well as weapon use. dietary isotopes suggest that he had benefited from a rich, high-protein diet, which also predisposed him to renal stones. during life he had developed an intracranial tumour, the placement of which may have affected movement of the right side of his body, including his well- developed right upper limb, and his ability to speak and comprehend speech. his remains also show evidence of a chronic infection of the maxillary dentition from dental caries, as well as other carious lesions. these are indications of the phys- ical consequences of a socially pre-eminent lifestyle that included the consumption of cariogenic foods. gristhorpe man had sustained four ante-mortem (i.e. all healed) traumatic injuries, two to his ribs, another to his neck, and yet another to his chin. these attest to an active lifestyle that exposed him to injury. the amesbury archer (named after the arrowheads among the grave goods accompanying this early bronze age male burial in wiltshire) also had sustained a crippling knee injury in his young adult years (mckinley, ). a worldwide review of traumatic lesions related to inter-personal conflict found that such injuries occurred overwhelmingly in males from the bronze age to the modern period (knüsel & smith, b). these sumptuously adorned men and their followers were not only able to deliver injurious blows, but also exposed them- selves repeatedly to injury as well. the neolithic forms a turning point in the level of violence (schulting, ; schulting & fibiger, ; smith, ) although there is noticeably more evi- dence of injuries resulting from interper- sonal violence in the neolithic than in preceding periods, there appears to be a more equal distribution of traumatic injuries between the sexes (schulting & wysocki, ; fibiger et al., ; knüsel & smith, b), attesting to the differing circumstance in which these wounds were received. neolithic warfare appears to have been more about surprise and hit-and-run tactics, as may be indi- cated by a lack of static, defensible forti- fied places. support for this statement comes in at least two additional forms of physical evidence, in addition to skeletal trauma: mass graves and bilateral limb asymmetry. the early neolithic mass grave at talheim, which schulting ( : ) describes as ‘paradigm-shifting’, was the first to provide evidence that apparent ‘tools’ (adzes) were responsible for cranial trauma that resulted in the deaths of mul- tiple men, women, and children (wahl & könig, ). it was not only in the early neolithic that such violence is documen- ted (meyer et al., , ), other notable examples being known from the late neolithic (meyer et al., ). already in the early neolithic, males buried with adzes seem to have employed their right upper limbs in activities that predisposed them to thrower’s elbow (villotte & knüsel, ), a disorder linked to single-handed tool-use that probably included weapons. schulting ( : ) notes that ‘we do not see a specialized warrior identity in the mesolithic or neolithic and that every able-bodied male would be expected to perform this role alongside his other roles: as hunter, farmer, herder, fisher, weaver, potter, etc.’. if discernible warrior graves are apparently absent, it appears that their activities seem to have been present. warriors, then, probably emerged before they became archaeologically visible in the bronze age (see jeunesse, ), when a more highly organized entourage of (male) warriors and more highly orchestrated warfare that is familiar to historians of the ancient world came into being. european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core when combined with the type of material associations described by treherne, these studies have the capacity to break the symbolic/utilitarian interpret- ive equifinality implicit in apparently socially-identifying objects. in short, a great corpus, made up of theory, historical precedent, and material cultural correlates, lacks a synthetic biological component, and we are thus left with the conundrum of whether elaborately interred individuals constitute an orchestrated symbolic, but in essence unreal or even misleading, representation, or a true reflection of the emergence of a socially differentiated group that contributes leaders, i.e. active social agents, wielding unequal power to influence social change. this question finds its correlate in the work of härke ( , ) on early medieval weapon burials, which are described by steuer ( ) as also representing a ‘warrior life- style’ in the early medieval period. as sug- gested in treherne’s essay, the key to unpicking this knot of ambiguity—to break the equifinality implicit in the term ‘weapon burial’—lies in the physical attri- butes of individuals buried in elaborate graves. the emergence of warriors in the bronze age may go far to explain some of the population movements/mass migra- tions that are thought to have taken place on a grand scale in the period (haak et al., ), but such an explanation may also be employed on a local or regional scale to account for the origin of warrior- leaders. this would also help resolve the question of whether individual cases represent true warriors—who had actually fought—and distinguish them from others who were non-combatants buried in ways which mimicked the warrior’s beauty, in a manner that is similar to the transform- ation from warrior to courtier-aristocrat of the later middle ages (see p. ). this diachronic perspective, hinted at in the conclusion of treherne’s piece, speaks for what appears to be a recurrent and endur- ing phenomenon of a certain type of mas- culinity. it seems clear that by the advent of the european bronze age, if not before, the martial component of mascu- linity had emerged, and it continues to be present in a less personally active but increasingly powerful and deadly form in leadership today. the ‘beautiful warrior’ twenty-one years after: bronze age warfare and warriors helle vandkilde the seminal article by paul treherne in the volume of this journal seems to have given rise to a mostly independent thread unrelated to the current surge in warfare research. the role of warfare and warrior aesthetics is briefly discussed against this background. warriors would seem topical to ques- tions of prehistoric warfare, which until c. was a marginal subject area in archaeology. since then, war has gained considerable momentum as a research theme and today the archaeology of warfare is firmly placed in the suite of archaeologies addressed. the brilliant ‘warrior’s beauty’ paper by paul treherne, published in in the european journal of archaeology (then the journal of european archaeology) can, given its many citations, be categorized as a high-impact article; it is a frequently accessed article on the journal’s website. against this back- ground, it is pertinent to ask if the study has had a role in driving the current inter- est in war and, hence, has influenced the new knowledge now emerging. are the visual appearance and bodily movements of the ancient warrior, sensu treherne, at all present in the archaeology of warfare now blooming? frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core in the twentieth century, the warrior was considered a heroic stereotype at the head of an ancient society that was deemed essentially peaceful. but, after the ‘discovery’ of the war-like reality of societies in the late s, warriors have paradoxically fallen out of the bronze age research limelight, although warrior elites sometimes figure in interpreta- tions (vandkilde, ). it is, therefore, timely to assess the value of treherne’s contribution. an impactful essay ahead of its time treherne’s essay contains a number of observations and theory-driven hypotheses, which have the potential to throw light on the main strands of change in neolithic and bronze age europe and increase our understanding of the role of the warrior in these societies. in addition, it is a mani- festo replete with theoretical insights: classic, mainstream, and scholarly. the position taken is not easily slotted in to any theoretical school or paradigm; the article works equally well as a grand history on an eurasian scale, and, by contrast, as an examination of the male body and equip- ment as both unique and reiterated materiality in life and death. this epis- temological stance embedded in classical history may explain the immediate success of treherne’s article, not least in the mid- s when much energy was invested in aligning with processual, post-processual, or post-structural persuasions. characteristically, the essay works with dualities rather than dichotomies. in fact, the inseparability of ideology and reality on the one hand, and of the body, iden- tity, and personhood on the other, may have been an eye-opener for many archae- ologists struggling to make sense of spe- cific archaeological remains, in particular burials: it became clearer that people’s beliefs were lived through their social interactions and affiliations, and that con- cepts such as ‘false consciousness’ tends to victimize, especially, those people ‘without history’ and thence to simplify complex pre- historic realities. people live out their ideolo- gies and form their identities through their bodies in an entanglement where power is an inherent element. in providing a simul- taneously sophisticated and straightforward framework for thinking theoretically about archaeological things, data, culture, and change, treherne was well ahead of his time. first, the essay can be read as a cri- tique of archaeology rooted in philosophy, while at the same time promoting body, gender, identity, agency, the senses, and even history as an interleaved package central to the interpretive agenda. second, the essay can be taken to be an innovative framework for better understanding the numerous weapons recovered in burials and hoards from around bc onwards, and here classical studies and early written sources support the argument well. the immediate impression is nevertheless that this second aspect has not been invigorated to any significant extent by the general aca- demic turn set out by treherne’s essay. internet data may confirm this broad canvas. even if the number of citations is likely to be an underestimate, the statistics in table show that treherne’s article has contributed more significantly to other subject areas (eighty-four per cent) than to warfare, weapons, and warriorhood (sixteen per cent). its main impact is on questions of identity and gender, body and agency, emotion, art, and the senses, in addition to general theory and overviews. its low impact (very few, if any, references) on the otherwise thriving genre of war studies is illustrated when leafing through a number of anthologies: e.g. those of carman & harding ( ); osgood et al. ( ); otto et al. ( ); ralph ( ). given this essay’s heading and principal message, european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core it is surprising that warrior studies show up in such a low proportion in the statistics, but this may relate to warriors being rather marginal to the current rise in warfare studies. in fact, a handful of major warrior studies do recognize treherne as central to the analysis of ancient warriors: harrison ( ); vandkilde ( b); harding ( ); knöpke ( ); schulting ( ). one could argue that it was keeley’s book (war before civilization, ) and the wars and genocide of the s that heralded research in prehistoric warfare. meanwhile treherne’s essay became one of the guiding threads in a par- allel thrust to populate prehistory with able-bodied real people, but this comprised few analyses of warriors until recently. treherne’s article thus seems to have insti- gated an independent thread of research mostly disconnected from the surge of warfare studies from to the present. while treherne’s article demonstrates a good knowledge of the archaeology outside the english-speaking world, the works quoting treherne come predominantly from the latter. german archaeology has recently discovered war as a research area; this kriegsarchäologie seems to largely be an inde- pendent development apparently little influ- enced by the global rise in war studies since , as the few cross-references reveal (e.g. meller & schefzik, ). it may be that the interest in war now manifest in german archaeology is a logical continuation, or off- shoot, of the strong kriegergräber tradition, which was also a major source of inspiration for treherne (p. ). more broadly, weap- onry is still an important research focus in germany (as well as elsewhere), albeit the interest has shifted slightly more towards investigations of damage and wear on deadly weapons, such as swords and spears, as well as research on traumata (e.g. peter-röcher, ; horn, ). furthermore, recent dis- coveries have been influential too, notably the corded ware multiple burial at eulau in central germany (meyer et al., ) and two early urnfield sites, the battlefield of tollense (jantzen et al., ) and the neckarsulm warrior cemetery (knöpke, ; wahl & price, ) in north-eastern and southern germany, respectively. in sum, the growing field of the archae- ology of warfare follows several research directions which have so far been little concerned with the beautifully-bodied warrior, despite his implicit capacity for violence. it may well be that the warrior needs to be instated as an instrumental agent in the sometimes war-like reality of prehistoric society. the bronze age warrior: epic hero or militant professional? treherne used as a springboard, firstly, the ostentatious panoplies of weapons deposited in the so-called kriegergräber and, secondly, homer’s warrior tales and their reinterpreta- tions in classical studies traditionally favouring masculine bodily aesthetics. the association of both these categories with grooming tools, dress and accessories, table citations of treherne . treherne archaeological themes citations year span overviews – identity-gender – rituals-death-burial – body-agency – theory, e.g. mind-matter – emotion-senses-art – weapons – warriors – warfare – sum source: google scholar february frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core drinking equipment, and wheeled vehicles may be a convincing argument that they represent the shared characteristics of warrior elites—centred on both the living and the dead masculine body: common life/ death style and norms, beliefs, appearance, as well as inbred social superiority and habits of cultural consumption. this ideol- ogy is accordingly lived through individua- lizing and communal action in the group of warriors among which courtly conduct is pre-eminent, not least during the funerals of companions. it is, indeed, the weberian notion of the status group which permeates the analysis and which is similar to van wees’ status warriors in the setting of homer’s epics ( ), or for that matter kristiansen’s warrior aristocracies in the bronze age ( , ). treherne does not use the word ‘hero’, which is neverthe- less implicit throughout his article, in which, furthermore, the concept of warrior elites is not criticized and becomes a static component of bronze age society. today we know that prehistoric warfare cannot be reduced to rituals such as treherne erroneously contends (pp. ), extending the paradigmatic absence of war and violence prevalent in much earlier archaeological interpretation, which also venerated the gallant warrior as the head of society. homeric warfare is, to put it simply, about prowess and honour, and about fame and glory on an epic scale; but bloody raids and piracy represent the reverse of the gleaming coin. van wees ( ) shows that homer’s epics narrate a social world in which rivalry thrived, and where power and leadership were con- stantly under pressure rather than making an undisputed, stable warrior hierarchy. ugly violence and brutal assaults, such as plundering cities for revenue and taking captives for slavery, are present as subtexts to the dominant narrative of heroic conduct, which also tends to evaporate when the fallen heroes are left unburied and mutilated on the battlefield, in danger of losing their social status. these are important nuances to con- sider in regard to bronze age archaeology too; the interface between heroic and violent realities is becoming clearer, but still needs further study. van wees’ find- ings can be said to parallel the duality present in the archaeological sources for the bronze age: there can, first of all, be no doubt that a heroic logic is embedded within much bronze age materiality in the same way as it is at the core of homeric society, reflected in particular in the iliad. this implies that heroization formed part of the social reality in both these connected worlds and later gave rise to the varied and probably quite widespread practice of hero cults (whitley, ; vandkilde, a), echoed in hesiod’s men of bronze and his notion of an age of heroes. against this background, it becomes prob- lematic merely to dismiss the hypothesis of warrior aristocracies, even though this institution needs to be nuanced in bronze age settings. treherne is not overmuch concerned with bodily techniques as phys- ical action, sensu mauss ( ), and is more in line with vernant’s ( a) aes- thetic body perspective. aesthetics on its own is, however, inadequate: through a more complete body perspective, warnier ( ) contends that warfare always involves the fighter’s subjectivity and that warriors are the professional agents specif- ically trained in the techniques of warfare. the movements of both body and weapons have to be synchronized to effect- ively overcome the innate fear, as mental- ity is clearly important for survival. secondly, new data strongly suggest that prehistoric warfare was quite widespread and often deadly: there is now substantial skel- etal evidence for war-related violence (e.g. schulting, ). kriegergräber have so far not revealed skeletal trauma—probably not european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core because it did not exist, but because the skeletons are generally badly preserved and often cremated. the social status of the warrior as sword carrier or as charioteer is effectively commemorated in the burial rites (e.g. clausing, ; winghart, ), and there is nothing to suggest that this did not have a bearing on conflict and war. a violent reality at the transition to the urnfield period emerges clearly from two recently excavated sites. around bc in the tollense river valley, numerous plundered corpses of warriors with projec- tiles often still embedded in their bodies were left on the battlefield by the victors (jantzen et al., ). this is paralleled at the cemetery of neckarsulm, dated to the early urnfield period (ha a ) (knöpke, ). both sites contain almost exclusively young male warriors, many of them for- eigners and probably mounted (wahl & price, ; brinker et al., ). this matches well the quantification of weapon burials calculated by clausing ( : ) with peaks at the beginning and end of this long period. earlier evidence, such as the corded ware burials at gjerrild and eulau, and the wassenar and over- vindinge burials dated to the transition to the middle bronze age, clearly show that war-related violence occurred, if not throughout the period then definitely at the thresholds of change (see otto et al., ; peter-röcher, ; vandkilde, b). these datasets concur with the outcome of use-wear studies of bronze age weaponry (e.g. kristiansen, ; mörtz, ; horn, ). in addition, weapons such as swords, spears, shields, and armour became more deadly, effective, and standardized over time, culminating in the urnfield period. while bows and arrows are infre- quent in burials and other deposits they are prominently attested across the periods in the data for skeletal trauma. this reveals that archery was instrumental in war, while it did not officially form part of the concept of heroic valour and of special codes of life/ death style conducted in the companies of warrior peers. warriorhood can thus be defined as a social identity springing from militant bodily-material interaction, but also from heroic tales of men, war, and glory. therefore, treherne’s warrior obsessed with his bodily appearance ought to be taken seriously when we add the violence that is also integral to the warrior’s being and doing. such an entwined reality for a bronze age warrior is in full agreement with the outcomes of the few warrior- focused studies mentioned in the intro- duction. if the identity of the warrior is disconnected from the activity of warfare, there is a risk that the many data obtained, notably for weaponry and trauma, will not further our knowledge of how war and its agents influenced history and vice versa. quantitative variations over time in trauma and weaponry already hint that warriors and their actions were placed cen- trally in the historical web of causes and effects with major thresholds at around bc, bc, and bc. the beauty of the chalk warrior: a reflection on treherne’s contribution to prehistoric martial culture melanie giles introduction in , archaeologists from the university of sheffield were excavating a late iron age-early roman farmstead—a so-called ‘ladder’ or ‘droveway’ enclosure—on the high wolds of east yorkshire (giles, ). among the objects in the box of finds that has made its way into my care, is a small, broken tablet of hard chalk with an almost translucent or bony quality. it is frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core roughly triangular and, even though it lacks a head, it is clearly carved to represent a human torso: a new, rare example of the ‘chalk figures’ first drawn by mortimer ( : fig. ) and published as a corpus by stead ( ). the fragment is damaged by both plough and mattock, yet some ori- ginal incised lines survive underneath the unwashed rime of loam: the double stripe of a belt, the flare of a sword’s hilt running up the backbone, and the sleeve-edges of both arms (figure f). the right sleeve reaches behind over the shoulder blade; the left hangs down, truncated abruptly where the front has sheared off in antiquity (figure ). this diminutive armed figure is- poised, frozen in the act of reaching for its sword—appealing to be understood in the context of the last century of iron age life in britain, and its difficult and undoubtedly bloody entry into the roman world. also saw the publication of paul treherne’s article on ‘the warrior’s beauty’, and an increasingly battered photocopy of this publication has accompanied me into the field ever since. useful evening reading matter on an east yorkshire wolds dig where iron age square burials cluster along streams fed by violent springs. an example of taut scholarship that drew theory into skilful marriage with bronze age material culture. an article glowing with bronze feasting equipment, weap- onry, and horse-gear, against which echo the worlds of homeric poetry and the bloody sheen of figures such as achilles and hector. yet at its heart lay overlooked and intimate objects of male bodily care: ‘accessories’ normally relegated to the domestic realm. the small piece of research presented here owes a debt of inspiration to this publication and its author. in the sections that follow, i want first to highlight its key strengths and then show how my own work continues to tack back-and-forth to this seminal article. ‘the warrior’s beauty’ treherne’s critique of the bronze age ‘warrior aristocracy’ model draws on embodiment and practice theory of the late s– s (particularly the theories inspired by mauss, bourdieu, and giddens), and the work of john barrett ( ), julian thomas ( ), and marie louise stig sørensen ( ) on ‘technologies of the body’, ‘lifestyle’, and ‘biographical’ approaches in archaeology. like them, he takes the materiality of the body and its life-cycle as a fundamental frame of human experience, meaning, and thus analysis. yet his article stands out from these studies through an explicit interest in the character of the warrior. treherne does not problematize this term (see giles, forthcoming), nor spend time discussing the scale and charac- ter of violence in later prehistoric europe, citing instead the ‘heroic combat’ of classical mediterranean literature as analo- gous evidence. he contrasts this kind of ‘sovereign warrior’ with the hoplite phal- anxes of late bronze age spartans or serried ranks of roman legionaries, for example. at the end of the article, brief allu- sions to medieval sacred masculinity, knightly valour, and later court aristocracy provide alternative models of male renown, which foreshadow the work of taylor (e.g. ) or gilchrist (e.g. ). it is, however, clear, as the article progresses, that treherne is arguing that these warriors were not inevitable socio-evolutionary products of complex societies: they were the outcome of deliberate choices to elevate and perpetuate a particular character, and celebrate the ideals they embodied. such bodies took very particular histor- ical and cultural forms, which required work: habitualized regimes of bodily train- ing, care, and adornment, alongside a suite of cultural customs which valorized the body as ‘a locus of individuality’ (treherne, : ). musculature, posture, hair, european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core equipment, and dress. the work of train- ing, practising, and honing one’s skills. the work of crafting, sharpening, and repairing arms. the symbolically charged arenas of hunting and dancing through which war- riors practised their arts. the drinking and eating through which warriors distin- guished themselves from others, celebrated their courage, and bound themselves to their comrades. and, not least, the work of fighting: being wounded, dying with honour, being remembered. this not only gave rise to a specific male ‘life style’ as he puts it, embodied in both ‘social practices and cultural representations’, but also a ‘death style … a socio-culturally prescribed way of expiring’ (p. ). throughout his article, treherne deploys objects normally dismissed as part of male vanity (‘horn, bone, and bronze combs, bronze tweezers, razors, mirrors and (‘tattooing’) awls’; p. ) and sug- gests they could be essential parts of the kit and care of the warrior. he reminds us figure . chalk figures from east yorkshire: (a) withernsea; (b) garton slack; (c) fimber, blealand’s nook; (d) malton; (e) garton slack; (f) wharram grange crossroads (after stead, with addi- tions, drawn by m. giles). frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core that personhood was ‘not limited to the boundaries of the epidermis’ (p. ), but could also be constituted through body art, hair styling, clothing, even the use of incense or oils, alongside actual arms, as part of costumes that ‘visually and acous- tically accentuated the body’ (p. ). qualities of youth, physical power, sexual potency, and courage are illustrated through the ‘blaze’ of light said to sur- round heroes such as achilles: a sheen that treherne discusses in relation to the fleshy-material amalgam of shields, breast- plates, blades, hair, muscles, sweat, used in such synergy with the warrior’s body that they became not just trappings but extensions of the self. treherne draws archaeologists away from the field of vio- lence itself into the most intimate rituals of self-care that protected and strengthened these figures, as well as the rites that dealt with their injuries; prepared and buried their corpses in a fitting send-off, and— their direct corollary—despoiled, stripped, and defamed the bodies of enemies. and finally, he points to the after-work of com- memoration: the graveside performances and monuments (warrior ‘stelae’ or tumuli, figurines or motifs) as corollaries of greek epic poetry, which fixed them in both the land and the memory of their brothers-in- arms and descendants. seminal to all of these ideas was the heavily referenced work of vernant ( b). performing beauty, performing violence: the iron age warrior treherne’s model of embodiment has received critical attention from bronze age scholars (e.g. brück, ) on rela- tional identity or fowler ( ) on per- sonhood. yet his notion that later prehistory marks the emergence of a form of ‘masculine beauty peculiar to the warrior’ (p. ) was a compelling one. methodologically, he made scholars look at the whole life-cycle of this persona through its associated material culture: not just weaponry, but objects of body care, statuary, figurines, and even burial as a kind of valorizing, material epigraph, ‘fixing a certain image in death’ (p. ). in my own field, james’s ( ) ‘call to arms’ (regarding the pacification of the iron age) has been complemented by seminal studies on weaponry (stead, ) and violence (redfern, ; armit, ; kelly, ; aldhouse-green, ); it created a richer understanding of the char- acter of iron age conflict and a more crit- ical approach to the ‘celtic warrior’ (creighton, ; hunter, ; giles, forthcoming). in my own work, i have combined osteological and material culture evidence to suggest that codes of honour- able conduct governed communities like the arras culture of iron age east yorkshire: agreed, staggered stages of con- flict before blood was shed, which were highly performative (giles, , ). it is into such arenas of swaggering bravado and bellicose posturing that we need to resi- tuate decorated weapons and chariotry—not just as intimidating for an enemy, but apo- tropaically effective for the warrior (giles, ). i have also revisited vernant’s idea that ‘dying well’—achieving a ‘beautiful death’—was not merely a way of dealing figure . the wharram grange crossroads fig- urine fragment: dorsal face (photo: m. giles). european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core with grief and enhancing status (p. ), but a vital means of grappling with the existen- tial ‘angst’ that gripped young men commit- ted to a brief but glorious life (p. ): achieving post-mortem honour particularly in the case of untimely, mysterious, or igno- minious deaths (giles, ). but what about the notion of ‘beauty’ specific to such warriors? let us return to the chalk figures. the chalk figures they emerge on the yorkshire wolds and surrounding vales in the context of a rad- ically changing world: the first century bc– first century ad (pre-dating the conquest of northern britain but continuing to be made, used, and deposited into the later roman period; stead, : – ). the final phase of this region’s square barrow cemetery rite witnessed a higher propor- tion of weapon burials than before (stead, ), suggesting a renewed focus on arms, reflected in later weapons caches such as south cave (evans et al., forth- coming). in an era when roman conquest and military occupation became a lived reality, it is not perhaps surprising that armed masculinity was culturally re-vita- lized. whether dealing with resistance and its suppression, collaboration, or recruit- ment as an auxiliary, the right to bear arms and the skill to wield them must have defined the aspirations of many young men in this region. between forty and fifty figurines are known: twenty-four complete/near-com- plete examples, including wharram (stead, : table ). they are carved in a variety of different kinds of chalk: some heavily modified, others nodules and plaques apparently selected for their torso form. both substance and appearance may have been key, not just for the ease of cre- ating such figures from an everyday mater- ial, but for its white, hard shine— analogous to bone while exuding the sheen of sweat which may have enhanced its perceived animacy (see conneller, ). details are finely incised (e.g. malton, figure d) or cut-back and excised to create three-dimensional effects (e.g. withernsea, figure a). the figures create a strong sense of an idealized body: composed, largely expressionless—simple eyes and a nose, rarely a mouth, and only then a flat line. perhaps this conjured the grim determination or fortitude expected of a man poised for violence, enduring pain, or steeled for death (see armit, ). rarely are they explicitly gendered: withernsea has a stylized phallus and scrotum, as well as a moustache and beard (or hood) and fimber may also have a pointed beard (stead, ). heads are often missing, perhaps a point of structural weakness but stead ( : ) also sug- gests that some may have been deliberately ‘decapitated’. arms are depicted (but not legs or feet): frequently shown in a dual posture of left-handed welcome or hospi- tality (spread open across the stomach) and right-handed ‘readiness’, reaching for or hovering above the sword—an apotro- paic gesture (giles, ) rather than a realistic depiction of unsheathing a blade (stead, : ). fourteen of the near-complete figures are depicted with swords (stead, : ), twelve running vertically or diagonally along the back and two at the right-hand side (anthoons, ). stead links this to the mid-scabbard suspension loops found with his group e (e.g. mid–late iron age east yorkshire: kirkburn k , wetwang slack chariot burials and ) and group f (first century ad ‘brigantian’ swords from north-west britain) swords (stead, ). these weapons are often composites of bronze or wooden scab- bards, shielding iron blades. la tène- inspired celtic art often draws the eye down the bronze scabbard to elaborate frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core chapes. hilts and pommels frequently combine organic materials (wood, horn, and, in the case of south cave sword , whalebone tooth and elephant ivory; o’connor, ) with exquisite glasswork, excised iron grips, or raised bronze plates and studs. rare scabbard fittings (rings, miniature terrets, and strap unions) would have fixed hide ties to belts. importantly, it is these lost, ‘ancillary’ organics and the details of woven cloth that form the major decorative focus on the figures. hems, hoods, collars, bands, and wrappings (sometimes covering the scabbard) are drawn as grids or alternating horizontal/ vertical stripes and herringbone patterns. these might represent highly localized weaving traditions that demarcated aspects of neighbourhood, lineage, age, or gender (giles, : ). on several figures (figure e) repeated, incised gashes, slashes, and scored lines overlie such clothing: sym- bolic wounding or killing of an ‘enemy’ figure perhaps, or representations of injuries endured—scars borne by a ‘hero’. discussion this reflection on treherne’s seminal work began with a new example of an iron age chalk figure. the brief example given here furthers treherne’s argument that the ‘beauty’ of such warriors resided in the melding of skilled body, kit, and experience: flesh marked by combat, but cared for; well-dressed hair and clothing; strappings, fittings, and sheathed blades. yet beauty also resided in posture and gesture … poised, prepared, ready … exuding not the moment of violence, but potential for bloodshed. they thus form an important, indigenous contrast to the classical world’s representation of nor- thern tribes—the noble, dying victim (e.g. the ‘dying gaul’), or the defeated and trampled barbarian (e.g. reitertyp tombstones, such as that of insus found in lancaster). the chalk figures were meant to stand outside of time, unmoved (quite literally, given the flat base and basal peg- hole on many examples; stead, : ). what was their purpose? the idiosyncratic nature of their crafting, the multiple frag- ments found at sites like garton slack, and their deposition among household debris (as with the wharram grange crossroads example) suggest these were not part of an elite art, but were made expediently, locally, and frequently. household deity, toy, game-piece, warrior-god, mythic ancestor (stead, : )? feared and symbolically dispatched enemy? venerated mnemonic of an hon- oured relative? intimate surrogate, even, for a body lost in conflict, defiled and defamed? we may never know. yet they tell us of a concept of the armed figure which (in treherne’s words) did not simply relate to appearance, but to living beautifully and dying well. aging well … dying beautifully paul treherne in the autumn of , i was invited to view a discovery brought to light in a gorge below the little medieval town of sovana, in southern tuscany. workmen clearing the vegetation around a large mass of volcanic tufo (tuff) found the block of stone engraved on its underside. when i arrived, local archaeologists had burrowed underneath the boulder, prop- ping it up with timber supports. lying on my back, i shut my eyes, as they instructed, and pulled myself into the narrow space beneath the rock. i shall never forget the sight when i opened my eyes again. i found myself face to face with a life-sized demon, a scylla or triton, carved more than two thousand years ago from the warm-hued stone. european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core the tomba dei demoni alati, as it is now known, was discovered by chance in a well-known necropolis where i, like countless others, had walked many times before. the winged demon once formed the pediment of a tomb, which had become detached centuries earlier from the high cliff face where the tomb itself was located. this accounted for the figure’s incredible state of preservation—his flowing hair, nude torso, and curling fishtails all fresh and crisp as if carved yesterday. further excavation revealed a high arched niche, in which a painted effigy of the deceased lay. the false-door was flanked by at least one lion and two other standing figures that were largely intact from the neck down. at the time, i was part of a collabora- tive project restoring the nearby siren tomb at sovana, first publicized by samuel ainsley and george dennis in . i was sent to grosseto to inspect a carved head that had been found half a century later amid the rubble around the tomb of the siren. the head had once belonged to one of two statues that flanked the central niche of the tomb’s façade, in exactly the same fashion as the more recent and better-preserved tomba dei demoni alati. after years in which it had been kept in the vaults of the archaeological museum, a plaster cast of the head was being made for restoration on site. intriguingly, the curator showed me something one could not observe from the fragmentary torso on site, yet confirmed by the figures from the newly discovered tomb. in each statue, one hand drew back a tress of hair, while the other reached across with a blade to cut it. there was something more that intrigued me. whereas the owner of the recent tomb was male, as advertised by a crude phallus etched in the rock face, the winged demons cutting their own hair were all female. the experience cast my thoughts back to the article i wrote in this journal in : ‘the warrior’s beauty: the masculine body and self-identity in bronze age europe.’ the paper grew out of an under- graduate degree in anthropology and classics and was adapted from a disserta- tion for an m.phil degree in archaeology at cambridge university, written in a few brief months over the summer of . the tomba dei demoni alati at sovana invoked many of the same themes that had informed my research. the monstrous scylla, heaving the deck of a ruined ship over his shoulders, reminded me of the threat of annihilation that death (at sea) evokes, devoid of any notion of a redemp- tive afterlife. the figures cutting their long hair recalled the contrast between beauty and bodily mutilation in death, like the siren whose song promised not the splen- dour of eternal renown, but a place among the bleached bones and rotting corpses in her coils. archaeologists have dated the sovana tombs to the third century bc, long after the iliad and odyssey were committed to writing and enshrined as part of a common literary tradition across wide areas of the mediterranean. explicit homeric scenes begin to appear in etruscan funerary art from at least the seventh century bc, in some cases showing divergence from greek versions of the tales. in my original article, i made much more sweeping claims about the relevance of homeric poetry to our understanding of masculinity and self-identity in later european prehistory, while deliberately avoiding questions as to how such a body of myth or epic tradition might have been transmitted, or adopted and reinterpreted in new environments. the purpose was not to pin-point homeric epic in time and space, much less to suggest, as an earlier generation of archaeologists mis- takenly did, that bronze age europe was frieman et al. – aging well: treherne’s ‘warrior’s beauty’ two decades later https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core somehow the heroic age of which ‘the bard’ had sung. homer, if he ever existed, composed his epics in the specific circum- stances of eighth-century greece, at a time when society was undergoing rapid social change. the poems themselves are layered with the accumulation of centuries of oral transmission, arguably reaching back to the bronze age. this is why archaeolo- gists have tended to approach them like monuments to be excavated for material traces of the past. instead, as ian morris explains, ‘material culture and poetic culture were two ways in which people in eighth-century greece constructed the social world within which they moved. both were important arenas in which people fashioned images of what they wanted the world to be, and challenged competing constructions which they did not like’ (morris, : ). in this light, the development of epic poetry itself only becomes intelligible when viewed, alongside funerary rites, as an historically contextualized response to fundamental questions of being: ‘the same strategy for dealing with death both inspires the treatment of the corpse and presides over the development of oral epic’ (vernant, b: ). the epic biography of a warrior often began with his funerary dirge but, more than this, heroic poetry and the ‘warrior grave’ functioned through homologous sig- nificatory structures. both comprised histor- ically unique modes of narrative representation, relying on formulaic tools— static epithets, stock phrases or imagery, and highly standardized or repetitive scenes, episodes, and sequences—involving the living and dead body. the exhibition of the individual in the earth and epic song were both performa- tive spectacles, mythopœic acts that summed up an existence led in pursuit of an aesthetic ideal. beyond simply idealising the lifestyle of the warrior, these representational media shared a common function: the enshrinement of personal reputation and status in collective memory through linking the individual to an exalted heroic ‘past’ which stands outside time and space. through imprinting par- ticular images or associations in the minds of the audience, they were the sole oppor- tunity for the individual to integrate and transcend death. by dying beautifully in the eyes of the living, the heroic warrior inscribed his singular being on the collect- ive memory of the group, even the soil itself, thereby achieving a measure of immortality. seen in this light, the introduction of writing was only another strategy for ren- dering memory durable, a set of signs like the earthen mounds placed at conspicuous locations in the landscape. paradoxically, however, the very technology that salvaged oral poetry for posterity altered its nature irrevocably, fossilizing it into a literary corpus open to scrutiny as abstract text. self-conscious attempts to invoke an heroic past, like the tomba dei demoni alati at sovana, would henceforth take place in a world of literary ‘quotes’. the funeral of misenus in the aeneid is deliberately styled after that of hector in the iliad, as is the tiber-side tumulus of the emperor augustus, to whom virgil dedicated his epic poem. late antique challenges to these monumental expressions of the heroic ideal would also be disseminated via the written word—the myriad ‘technologies of self’, as foucault liked to call them, of which christianity was the most far reaching. on the fringes of europe, where, over the early middle ages, christian literacy made inroads into what were still, essen- tially, prehistoric societies, surviving epic poetry and material culture reveal a great deal about changing notions of the body, masculinity, and personhood. read side by european journal of archaeology ( ) https://www.cambridge.org/core/terms. https://doi.org/ . /eaa. . downloaded from https://www.cambridge.org/core. carnegie mellon university, on apr at : : , subject to the cambridge core terms of use, available at https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core side, rather than as passive reflections of one another, the sutton hoo ship burial and funeral passages in beowulf offer a rich and complex picture of the colliding worldviews and different ‘psychic fabrics’, as seamus heaney put it, that are woven into the anglo-saxon poem—a piece of narrative that speaks more than ever to us, living as we do, ‘[i]n an age when “the instability of the human subject” is con- stantly argued for if not presumed’ (heaney, : xvii). one of the challenges for those studying the past is the way in which we inevitably look at the body or masculinity, as we do with everything else, through the lens of modern values, preoccupations, and con- cerns. i shall never forget one evening in a pub in cambridge shortly after my article was published when a fellow student enthused that i had discovered ‘queens in the 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http://www.oxfordhandbooks.com/view/ . /oxfordhb/ . . /oxfordhb- -e- ?rskey=c tqfi&result= http://www.oxfordhandbooks.com/view/ . /oxfordhb/ . . /oxfordhb- -e- ?rskey=c tqfi&result= http://www.oxfordhandbooks.com/view/ . /oxfordhb/ . . /oxfordhb- -e- ?rskey=c tqfi&result= http://www.oxfordhandbooks.com/view/ . /oxfordhb/ . . /oxfordhb- -e- ?rskey=c tqfi&result= http://www.oxfordhandbooks.com/view/ . /oxfordhb/ . . /oxfordhb- -e- ?rskey=c tqfi&result= https://www.cambridge.org/core/terms https://doi.org/ . /eaa. . https://www.cambridge.org/core aging well: treherne's ‘warrior's beauty two decades later introductory remarks catherine j. frieman gender and personhood in the european bronze age joanna brück comments on paul treherne's ‘the warrior's beauty : the masculine body and self-identity in bronze age europe katharina rebay-salisbury warrior's beauty: revisited from a nordic perspective sophie bergerbrant an iberian perspective on ‘the warrior's beauty sandra montón subías the warrior's seduction joanna sofaer the ongoing significance of paul treherne's classic article ‘the warrior's beauty: the masculine body and self-identity in bronze-age europe (journal of european archaeology, ( ), – .) in recognition of the th volume of the european journal of archaeology christopher j. knüsel the ‘beautiful warrior twenty-one years after: bronze age warfare and warriors helle vandkilde an impactful essay ahead of its time the bronze age warrior: epic hero or militant professional? the beauty of the chalk warrior: a reflection on treherne's contribution to prehistoric martial culture melanie giles introduction ‘the warrior's beauty performing beauty, performing violence: the iron age warrior the chalk figures discussion aging well … dying beautifully paul treherne references ed author title pub date note available from pub type edrs price descriptors identifiers abstract document resume ir cheunwattana, aree; meksawat, pimol small is beautiful: the library train for homeless children. - - p.; in: libraries and librarians: making a difference in the knowledge age. council and general conference: conference programme and proceedings ( th, boston, ma, august - , ) ; see ir . for full text: http://www.ifla.org. reports descriptive ( ) speeches/meeting papers ( ) mf /pc plus postage. at risk persons; children; *childrens libraries; foreign countries; *homeless people; *library development; library facilities; *library services; rail transportation; user needs (information); users (information) thailand this paper presents the story of an effort in thailand to reach out to children in high-risk situations by providing them with a library on old train carriages. the library train project was initiated in by the railway police division within the royal police office. it is aimed at offering education services to homeless children as a way of reducing the crime rate and child exploitation by channeling children to more constructive activities. the library is equipped with a book collection, toys, and computers. it serves as an informal classroom where learning activities take place every day. the children learn to read and write and to appreciate cleanliness, good health, and beauty in a carefully designed and nurturing environment. the paper also highlights creative approaches used by the project's initiator to gain support from governmental and non-governmental organizations, mass media, libraries, and the general public. (author/mes) reproductions supplied by edrs are the best that can be made from the original document. bosr. ii th ifla council and general conference august - , code number: division number: professional group: joint meeting with: meeting number: simultaneous interpretation: - (ws)-e viii regional activities: asia and oceania workshop small is beautiful: the library train for homeless children aree cheunwattana and pimol meksawat srinakharinwirot university bangkok, thailand abstract: permission to reproduce and disseminate this material has been granted by a.l. van wesemael to the educational resources information center (eric) u.s. department of education office of educational research and improvement educational resources information center (eric) pk this document has been reproduced as received from the person or organization originating it. minor changes have been made to improve reproduction quality. points of view or opinions stated in this document do not necessarily represent official oeri position or policy. the paper presents an inspiring story of a determined effort to reach out to the children in high-risk situations providing them with a charming library on old train carriages. the library train project was initiated in by the railway policemen of the railway police division within the royal police office, thailand who also look after its operation. it is aimed at offering education services to homeless children as a way of reducing the crime rate and child exploitation by channeling children to more constructive activities. the library is equipped with a book collection, toys and computers. it serves as an informal classroom where learning activities take place everyday. the children learn to read and write and to appreciate cleanliness, good health and beauty ftom a carefully designed and nurturing environment. this paper also highlights creative approaches used by the project's initiator to gain support from governmental and non-governmental organizations, mass media, libraries and the general public. street children in thailand since the past decade, thai society has become confronted by an alarming problem of wandering street children. poverty, broken families and negligent parents drive the troubled children from home to the streets in big cities like bangkok, chiang mai, and pattaya. in the office of the national education commission reported there were approximately , street children in thailand. however, a christian rft; best copy available priest who runs a social welfare center for children commented that this figure was just a tip of the iceberg. street children usually are in poor health conditions, physically, emotionally and even mentally in some cases. they wander from place to place and struggle to survive from day to day. some earn small money by doing humble jobs such as washing dishes, polishing shoes or selling newspapers, garlands, flowers and lottery tickets. others beg for money, steal or scavenge through rubbish for what they can eat, use or sell. they hang out around temples, food markets, department stores or railway and bus stations where they can easily fmd food and living facilities. they sleep under bridges, on the beach, at construction sites or in any deserted place. most of them have not opportunities to attend school and become easily cheated. some join criminal gangs, many others have been victimized through drugs, child labor and prostitution. child welfare services provided by the government are not adequate. detention centers are criticized for their negative approach in looking after children, for lack of warmth and loving environment, and for rigid control enforced by strict rules, discipline and punishment. the growing problem of street children has raised concerns among organizations involved with children. currently, several governmental and non- governmental agencies and kind-hearted individuals devote their attention, money, time and efforts to help solve the problem, including the railway police division that runs the library train project. the library train project the library train project was initiated in by police major general jarumporn suramanee, the commander of the railway police division, the royal thai police office. the library project, in fact, stems from the streetside railway police teachers project in which the railway police helped solve the problem of street/homeless children in hua lumpong train terminal area through a non-formal education program. this program is aimed at teaching basic functional literacy as well as social norms to enable street children to survive in a normal society. with a positive approach, it also helps prevent these children from committing crimes and protect them from child exploitation. each day a three-hour class took place in the terminal platform or railyard amid the noise, air pollution and possible danger from the busy locomotive traffic. being aware of the problem, commander suramanee looked for a place more conducive to learning. he proposed to provide a proper classroom using old train carriages. the governor of the state railway of thailand, seeing many benefits to be derived from the suggestion, gave two train carriages to the project. a vacant plot of land at the division's headquarters was set aside for locating the carriages. beautiful junks being a library minded person, commander suramanee planned not only a classroom but also a library to support the education of homeless children. after four months of modification (april - august ), the biggest pieces of junk in the railyardtwo old train carriageswere transformed into a small beautiful library ( square meters per carriage). it is named in thai hong samud rotfai yoawachon, which means the library train for children. the railway police commander planned, managed and monitored the modification, which was undertaken by the railway police officers and workers. the work clearly reflects the idea of conservation through the reuse of thrown away materials. the commander himself sorted through the pile of old train components to acquire gadgets, posters, and decorating items. they were either repaired or remade with taste and put to good use. thus the interior of the library was designed in a way that the charm of the old thai trains is preserved. such design attracts both children and adults. children are fascinated by its antique look, and for adult visitors, it brings back the memories of childhood. the first carriage serves as a library. books and magazines are mostly acquired through donation. however, donated items are sorted out and only those in good condition and with appropriate contents are selected to fill the shelves. the collection is roughly classified according to types of publications and subjects. it contains books for children and adults. the library is intended for leisure reading, which will encourages children to develop a good reading habit. it also owns some basic reading materials that support education such as textbooks, teachers' guides, non-fiction and reference books. the second carriage serves as a classroom and area for recreational activities. a three-hour class that was once arranged around the train terminal currently takes place daily in the other carriage of the library. this carriage is equipped with a television set and four macintosh computers loaded with computer- assisted instruction (cai) software. the computers help children learn subjects such as mathematics and english faster in a fun way. education embedded in a carefully designed environment the library is located in a -square-meter compound, which is very carefully designed to educate children. the area is park-like, green and shady with trees. a herb garden provides a natural means of learning. children learn the properties of different herbs and know how to use them for cooking or healing minor injuries and sickness. they learn how to nurture life through taking care of the garden. hygiene is introduced when they are taught to take care of themselves, the library and its surroundings. art is integrated in every design and decoration. old train and railway components such as a steam engine, lamp posts, and railroad signs, used to decorate the place and put on display, illustrate a museum concept. sports facilities enable children to exercise, play and improve their health conditions. by working and playing together, children learn about teamwork, roles and responsibility, self-discipline, and public spirit. classroom education also takes place every day for about three hours a day, usually in the afternoons. nine volunteer police teachers, both female and male, are divided into three groups that take turns to teach and take care of the children. the teachers are trained to understand the psychology of troubled children. after the relationship between the teachers and these homeless children is established, the children will call their teachers "mama" and "papa." the teachers automatically take parental roles. in addition to teaching, they look after the well being of the children and protect the rights. in each class, there were about ten boys/ young men. their ages range from to . they are taught and taken care by three teachers who can afford to pay them individual attention when needed. subjects taught include reading, writing, numeracy, computer skills, civics and drug education. survival skills and social norms are integrated in teaching. the number of children attending classes varies, as they are free to come and go. the railway police commander pointed out, "street children have a strong sense of independence because they have struggled on their own long enough before coming to us. we would only drive them away if we impose strict rules on them. so we need to adopt a positive approach and make them trust us. after gaining their trust, steering them to the right direction will not be too difficult a task. anyway, for those who want to stay, we provide them beds, meals and medical care." after class, the children can read in the library, play with the computers or watch television. they can do outdoor activities, play some sports, or go to work, if they have jobs. according to the commander and volunteer police teachers, the children have shown signs of improvement. they have become less aggressive and speak more politely. they are more willing to lend helping hands to the teachers such as taking care of younger children. some have stopped sniffmg glue. those who work and earn are taught to save money by opening their bank accounts. at present, three boys who have been with the project from the beginning have continued their studies in the non-formal education programs of the ministry of education. the library train is also for the community not only the homeless children but also the railway police and the community have benefited from the library train project. the library and the mini park are open to the public everyday. students from other schools come to use the library. some small children ask their parents to bring them to the library because they found it fascinating. in a quiet corner, some users are found to do serious reading. people who reside in the neighborhood drop in to read newspapers, take a leisure walk, or rest under the shady trees. college students come to organize education or reading promotion activities. library science students, teachers and librarians pay numerous visits to learn about innovative ideas. the railway police commander tirelessly tells the inspiring story of the beautiful library. gaining support from the public when started, the library train project did not have any financial support. contributions came in other forms. the governor of the state railway of thailand provided the train carriages, land, necessary equipment, and free medical care. the railway police officers give time and labor to modify the library and the landscape. volunteer police teachers devote their time and efforts to teach and take care of the children. organizations that provide social welfare and education services for children such as the foundation for the better life of children, the mercy center, and the ministry of education offer consultation and cooperation. the commander and his family donated the first amount of money to get the project off the ground. when the library was completed, its attractive look and its humanitarian and educational objectives drew the attention of the public and media. contribution in cash and kind began to flow in. the nortel network company donated four macintosh computers to support education. sahawiriya, a local computer software company, offered some educational software. the canadian embassy donated can$ , through the canadian fund for local initiatives (in thailand). this amount is for a two-year lunch program and expenses of the children under the project's care. books, toys, clothes, food and cash donations also come from individuals who heard of the project or visited the library. an australian couple pays regular visits to the library, particularly the wife who, in addition to donation, organizes an informal english and art classes which the children enjoy. several international organizations have visited the library, for instance, save the children from the uk, the united nations children's fund (unicef), and university administrators from japan. the library train project is also popular among the media locally and internationally. the project has been aired on reuter, cnn and nhk. a model for community libraries several private and public agencies have expressed their interest in the success story of the project. they feel impressed by the innovative aspects and holistic approach in using the library to solve social problems and develope a positive image of the police force. the railway police have been encouraged to launch similar projects in other areas of the city. recently, the railway police division with funding from the siam cement foundation has begun a new library project for a slum community in bang sue district. the upcoming library is patterned after the successful library train. it is aimed to serve the community of which many young people are addicted to drugs and the majority of residents are under-educated and unemployed. while railway police teachers administer an educational program, a librarian will be hired to provide library services. useful approaches for librarians the library train may not offer professional library services as what we see in standard libraries. however, it clearly reflects an important concept of libraries making a difference in the society. this particular library has renewed many lives of street children. the public find the project meaningful and welcome it with overwhelming support. the project is cleverly designed. while it is based on the community's problems and needs, it has brought about an appreciation of the role of the railway police. it started as a small and manageable project through the maximization of limited resources. without budget, it adopted the sustainability concept of renovate, repair, remake and reuse. in designing the educational program for street children, a holistic approach is used. education takes place in a classroom as well as in a carefully designed environment. a natural means of education used is appropriate for the target group. the library, equipped with print and computers, is provided to support literacy, non-formal education and voluntary reading. social norms are integrated in teaching to prepare the children to return to normal life. institutional cooperation is another strategy used. the project works with several other organizations in dealing with the issue of street children. the spirit of cooperation helps the project initiator and staff to achieve their goal under resource constraints. it also increases the capacity of the project to expand its activities. through different media, the project has become widely known and gained participation. in introducing the project to the visitors, the railway police commander always provides well-prepared handouts to the audience to ensure that essential information has been communicated correctly. on top of everything, all project staff members work with deep commitment to contribute to the betterment of the society. strong leadership, flexibility and adaptability are demonstrated in the ways they solve problems and accomplish tasks. in the opinion of the railway police commander, librarians also need flexibility and adaptability in designing library services to meet the needs of the community. "responsibility is not enough! commitment and service spirit are ingredients for successful efforts. if librarians work with a service spirit, they will certainly earn respect and support from the community," he said. we, librarians, have been often criticized for our rigid adherence to rules and regulations and obsession to the technical side of library management. many of us fail to make our roles visible to the community. the authors sincerely hope that the ideas and approaches illustrated in this paper will be useful and adaptable in making library services more meaningful, and that one can start small and yet provide beautiful services. references assavanonda, a. ( , september ). street kids have moral system. bangkok post. available at http://scoop.bangkokpost.co.th assavanonda, a., & sukrung, k. ( , september ). expert says thailand turns into hub of child trafficking. bangkok post. available at http://scoop.bangkokpost.co.th bunnag, s. ( , september ). hua lampong big shelter for many street children. bangkok post. available at http://scoop.bangkokpost.co.th charoenpo, a. ( , may ). railway bogies to house school. bangkok post (home), p. . charoenpo, a. ( , april ). railway police extends its popular education project. bangkok post (home), p. . jinakul, s. ( , august ). pulling street kids off the rails. bangkok post (perspective), p. . jinakul, s. ( , may ). hope finally floats for street kids. bangkok post. available at http://scoop.bangkokpost.co.th suramanee, j. ( ). the library train and the streetside police teachers project. (photocopy) tangkananurak, w. ( ). dek reron: panha lae tang-ok [street children: problems and solutions] . bangkok, thailand: sathaban pra pokklao. ************************************************* acknowledgements the authors would like to thank the commander of the railway police division, pol maj-gen jarumporn suramanee and the volunteer railway police teachers and officers for kindly hosting our several visits, allowing us to observe their activities and providing us information about the project. we also wish to thank dr: maria laosunthara for guiding us to study this innovative project, lending her kindest support and editing this paper. aree cheunwattana department of library & information science faculty of humanities, srinakharinwirot university email: areecha,psm.swu.ac.th pimol meksawat central library, srinakharinwirot university email: pimol@p sm. swu.ac.th u.s. department of education office of educational research and improvement ( eri) national library of education (nle) educational resources information center (eric) notice reproduction basis i eric i this document is covered by a signed "reproduction release (blanket) form (on file within the eric system), encompassing all or classes of documents from its source organization and, therefore, does not require a "specific document" release form. this document is federally-funded, or carries its own permission to reproduce, or is otherwise in the public domain and, therefore, may be reproduced by eric without a signed reproduction release form (either "specific document" or."blanket"). eff- ( / ) rev. virtual quim. |vol | |no. | | - | artigo a beleza invisível da biodiversidade: o táxon rubiaceae valli, m.; young, m. c. m.; bolzani, v. s.* rev. virtual quim., , ( ), - . data de publicação na web: de janeiro de http://rvq.sbq.org.br the invisible beauty of the biodiversity: the rubiaceae taxon abstract: the brazilian biodiversity is one of the richest in the world, distributed in different biomes, among the most important, are the cerrado, atlantic forest and amazon rainforest. it is estimated that these ecosystems are home to about million plants, animals and microorganisms, representing a vast field of research. this immense biological treasure visually fills the beauty of the landscapes that has delighted generations and represents an incalculable molecular wealth, often unnoticed, because they are not visually noticeable. in this paper the beauty of the plant species is highlighted by presenting a formidable beauty, which is not visible to the eyes, the molecules can provide great utility. thus, the chemistry of metabolites extracted from our biodiversity and especially of plants is fascinating and architecturally beautiful. as a highly sophisticated laboratory, plants produce novel structures that stimulate the creativity of chemists and may be useful as drugs, dietary supplements, cosmetics and agrochemicals. given the molecular complexity and diversity of the many plant groups, the rubiaceae family was chosen for this short review, for suitably representing the visible and the invisible beauty of our biodiversity. keywords: rubiaceae; biodiversity. resumo a biodiversidade brasileira é uma das mais ricas do mundo, distribuída em biomas distintos, dentre os mais importantes, encontram-se o cerrado, mata atlântica e floresta amazônica. estima-se que esses ecossistemas abrigam, cerca de milhões de plantas, animais e microorganismos, representando um vasto campo de pesquisa. essa imensa riqueza biológica, visualmente enche as paisagens de beleza que vem encantando gerações e representam uma riqueza molecular incalculável, muitas vezes despercebida, por não serem visualmente perceptíveis. neste texto a beleza das espécies vegetais é ressaltada por constituir uma beleza formidável que não é aparente, as moléculas, que pode fornecer ampla utilidade humana. assim, a química dos metabólitos extraídos de nossa biodiversidade e especialmente de plantas é fascinante e arquitetonicamente bela. como num laboratório altamente sofisticado, as plantas produzem estruturas inéditas, que estimulam a criatividade dos químicos e podem ser úteis como fármacos, suplementos alimentares, cosméticos e agroquímicos. dado a complexidade e diversidade molecular dos inúmeros grupos vegetais, a família rubiaceae foi escolhida para esta pequena revisão, por representar satisfatoriamente a beleza visível e a invisível de nossa biodiversidade. palavras-chave: rubiaceae; biodiversidade. * universidade estadual paulista, núcleo de bioensaios, biossíntese e ecofisiologia de produtos naturais, instituto de química, departamento de química orgânica, cep - , araraquara-sp, brasil. bolzaniv@iq.unesp.br doi: . / - . http://rvq.sbq.org.br/ mailto:bolzaniv@iq.unesp.br http://dx.doi.org/ . / - . volume , número revista virtual de química issn - janeiro-fevereiro rev. virtual quim. |vol | |no. | | - | a beleza invisível da biodiversidade: o táxon rubiaceae marilia valli, a maria claudia m. young, b vanderlan s. bolzani a, * a universidade estadual paulista, núcleo de bioensaios, biossíntese e ecofisiologia de produtos naturais, instituto de química, departamento de química orgânica, cep - , araraquara-sp, brasil. b seção de fisiologia e bioquímica de plantas, instituto de botânica, cp , , são paulo- sp, brasil. * bolzaniv@iq.unesp.br recebido em de janeiro de . aceito para publicação em de janeiro de a cultura humana tem sido profundamente influenciada pela biodiversidade e espécies vegetais, particularmente as identificadas como possuindo usos medicinais. isto foi estabelecido por um longo processo de seleção realizado por populações antigas em todo o planeta. hoje em dia, o conhecimento a respeito das propriedades medicinais das plantas tem sido um dos focos da investigação científica na área de produto naturais, devido aos grandes avanços que essa área tem proporcionado à fitoquímica moderna e química medicinal. dado o número de espécies de plantas na terra e as numerosas vias biossintéticas capazes de produzir a extraordinária diversidade química, a biodiversidade em ambientes tropicais e equatoriais, oferece um potencial particularmente rico em compostos biologicamente ativos que podem ser usados como modelos para a química medicinal e descoberta de fármacos. a família rubiaceae, com suas folhagens majestosas, e belas flores, representam também a beleza invisível de nossa rica biodiversidade. espécies de rubiaceae estão distribuídas em cerca de gêneros, e muitas têm importância econômica e terapêutica reconhecida no brasil e em outras regiões do planeta. um exemplo é a coffea arábica, o popular café, fonte de riqueza econômica para vários países. o estado de são paulo tem ca. ca. espécies registradas, entre elas, ervas, arbustos ou árvores, ocorrentes especialmente no cerrado brasileiro. essas espécies contém grande diversidade de metabólitos secundários: iridoides, alcaloides indólicos, antraquinonas, flavonoides, derivados fenólicos, diterpenos, triterpenos, e outros tipos de alcaloides. algumas espécies estudadas previamente pelo grupo de pesquisa acumulam substâncias bioativas de classes distintas. rudgea virbunoides, uma espécie abundante em todo o cerrado brasileiro, é rica em triterpenos e saponinas pentaciclícos figura . nosso grupo de pesquisa vem estudando espécies de rubiaceae ao longo de anos e resultados obtidos são interessantes, por terem contribuído para o perfil químico da família, ainda pouco estudada e para a quimiotaxonomia, uma vertente importante para a taxonomia de um grupo vegetal complexo. no decorrer do texto estão descritos alguns resultados decorrentes de estudos de espécies vegetais deste táxon de angiospermae, e especialmente as com relatos de usos na medicina tradicional e, portanto, como potencial para estudos de mailto:bolzaniv@iq.unesp.br valli, m. et al. rev. virtual quim. |vol | |no. | | - | química, farmacologia e toxicologia objetivando a descoberta de potenciais candidatos a fitofármacos. uma grande quantidade de metabólitos secundários isolados de rubiaceae estão também disponíveis na base de dados do nubbe (nubbedb). a nubbedb foi recentemente criada de modo a tentar suprir uma das dificuldades das áreas de produtos naturais e química medicinal que é a falta de dados organizados disponíveis. a nubbedb está disponível online de livre acesso (http://www.nubbe.iq.unesp.br/portal/nubb edb.html) contendo informações botânicas, químicas e biológicas dos metabólitos secundários e derivados obtidos da biodiversidade brasileira. a base de dados pode ser útil para a pesquisa em química de produtos naturais, planejamento de moléculas bioativas, metabolômica e dereplication. figura . rudgea virbunoides, espécie de rubiaceae do cerrado brasileiro um dos primeiros estudos sobre a química do gênero alibertia foi realizado pelo grupo de pesquisa nubbe com a. macrophylla, figura , comum nos cerrados brasileiros e popularmente conhecida como marmelo do campo. sem qualquer registro fitoquímico na literatura, a espécie a. macrophylla foi escolhida para estudo de fracionamento e purificação dos metabólitos secundários de um extrato polar obtido de folhas, previamente diagnosticado como sendo fungitóxico. pesquisas anteriores com diversas espécies de rubiaceae de cerrado e amazônia comprovaram a presença de fitoalexinas em resposta a inoculação de fungos fitopatogênicos. no entanto, nossos experimentos com as espécies a. macrophylla e a. myrcifolia mostraram resposta fitoalexínica negativa durante todo o ano. por outro lado, a. macrophylla exibiu forte atividade antifúngica demonstrando a presença de substâncias de natureza constitutivas, identificadas como sendo iridoides. além desta classe especial de monoterpenos, o gênero alibertia é também conhecido pela ocorrência de triterpenos e derivados fenólicos. derivados fenólicos como o ácido cafeico ( ) e seus ésteres ( , ) também foram isolados do extrato polar das folhas de a. macrophylla (figura ). valli, m. et al. rev. virtual quim. |vol | |no. | | - | figura . a. macrophylla, espécie frequente nos cerrados brasileiros, popularmente conhecida como marmelo do campo é rica em iridoides antifúngicos o ácido cafeico e outros ésteres hidroxicinâmicos têm função biológica importante contra herbívoros e patógenos. em outro estudo, o extrato alcoólico das folhas de a. macrophylla revelou uma mistura epimérica de iridoides não glicosilados ( - , figura ) que mostrou atividade inibitória de crescimento dos fungos aspergillus niger, cladosporium cladosporioides, c. sphaerospermum e colletotrichum gloesporioides. a ocorrência dessas substâncias nas folhas de a. macrophylla explica suas propriedades fungitóxicas. , or o ho ho r h ch ch c h ch ch(ch )ch ch oh figura . Ácido cafeico ( ) e seus ésteres ( , ) isolados de a. macrophylla o oo h h r r r r r r oh h oh oh h oh oh oh h oh oh h figura . iridoides ( - ) isolados de a. macrophylla valli, m. et al. rev. virtual quim. |vol | |no. | | - | não apenas as folhas, mas também os galhos acumulam metabólitos secundários de estrutura química intricada, que fascinam pela beleza de seus arranjos moleculares de grande complexidade. dos galhos de a. macrophylla foram isolados e identificados, triterpenos (α-amirina, β-amirina, α- amirenone, β-amirenone, lupeol, lupenone, germanicone, ácido ursólico e oleanólico), iridoides ( α- e β-hidroxigeniposídeo, gardenosídeo, shanzisídeo metil éster, e ácidos fenólicos (cafeico, vanílico e protocatecuico). , a ocorrência dessas substâncias em alibertia está em concordância com a correlação quimiossistemática e posicionamento botânico do gênero na subfamília ixoroideae. adicionalmente, dos galhos de a. macrophylla foi isolado o diterpeno ent- caurano- β, α, α-triol ( , figura ), até então inédito na literatura, constituindo-se o primeiro registro do isolamento de um diterpeno cauranoídico no gênero alibertia em rubiaceae. mesmo que a família rubiaceae seja caracterizada pela biossíntese de iridoides e alcaloides indólicos, a presença do diterpeno cauranoídico na espécie é de interesse quimiotaxonômico e pode ser um indicativo de afinidade filogenética entre alibertia e o gênero coffea, também conhecido pelos cafestóis ( , figura ), diterpenos do tipo caurânico muito peculiar e ocorrência restrita ao táxon. ho h h ho oh h oh oh o figura . diterpeno ( ) isolado de a. macrophylla e cafestol ( ) isolado do gênero coffea alibertia edulis conhecida como “marmelada-bola” é uma pequena árvore amplamente distribuída no cerrado brasileiro, especialmente nos estados de goiás, mato grosso e são paulo, cujos frutos são apreciados pelo sabor doce figura . o extrato de acoet de a. edulis demonstrou forte atividade contra os patógenos candida sp. e cryptococcus neoformans. dos galhos dessa espécie foram isolados o iridoide éster metílico β-hidroxi- -epigardosideo ( ) e a saponina pomolato de β-o-[α -l- ramnopiranosil-( - )-o-β-d-glucopiranosil-( - )-o-β-d-glucopiranosil]- -o-β-d- glicopiranosideo ( ) (figura ). figura . os frutos alibertia edulis, popularmente conhecida como marmelada-bola são comestíveis e saborosos valli, m. et al. rev. virtual quim. |vol | |no. | | - | o ho h h ho o o oh ho h ho h hohh ooh ho o oh o ho ho ho o o o ohho ho oho ho ho o o ho ho ho o figura . iridoide ( ) e saponina ( ) isoladas de a. edulis o iridoide ( ) e a saponina ( ) até então inéditos na literatura mostraram atividade inibitória moderada nas cepas de candida albicans e c. krusei. taninos também foram detectados pelo teste com fecl e gelatina/nacl, o que poderia justificar a toxicidade observada nos microorganismos usados no experimento. a presença dos triterpenos oleanólico e ursólico no extrato das folhas de a. edulis está de acordo com o posicionamento de alibertia na tribo gardenieae da família rubiaceae, caracterizada pela ocorrência de iridoides e da ocorrência significativa de triterpenos tentacíclicos. dados taxonômicos sobre o gênero tocoyena registram cerca de espécies, todas de natureza arbórea. as de pequeno porte e arbustos são típicas do cerrado, sendo que algumas também ocorrem na floresta amazônica. o gênero tocoyena pertence à subfamília ixoroideae, e tribo gardenieae-gardeniineae e, assim como alibertia, biossintetizam iridoides, considerados os marcadores quimiotaxonômicos em todos os níveis hierárquicos da subfamília. tocoyena formosa figura é uma pequena árvore ornamental que cresce nas regiões secas do brasil central, é conhecida como “genipapo do campo”, e se destaca na época da floração pelas belas flores amarelas. o extrato das folhas desta espécie após serem submetidos a uma série de ensaios para avaliação de atividade antitumoral com cepas de saccharomyces cerevisiae, mostrou- se inativo, mas ao serem testados nos fungos cladosporium cladosporioides e c. esphaerospermum inibiram todas as cepas testadas, indicando a presença de substâncias antifúngicas. o fracionamento bioguiado do extrato das folhas levou ao isolamento dos iridoides com propriedades antifúngicas α- e β-gardiol ( , ) éster metílico de mollugosideo ( ) e, formosinosideo ( ) (figura ), até então inédito na literatura. o extrato dos galhos também foi fracionado e o -o-trans-feruloil teucreina ( ) (figura ) isolado, foi descrito como inédito, ao lado de uma saponina e um flavanol glicosilado, previamente descritos. , a atividade fungitóxica foi detectada também nos iridoides isolados de a. macrophylla, evidenciando os iridoides como uma classe de monoterpeno com propriedades antifúngicas bastante interessantes, além de serem marcadores químicos bastante peculiares nas de rubiaceas da região de cerrado. valli, m. et al. rev. virtual quim. |vol | |no. | | - | figura . t. formosa, conhecida como “genipapo do campo, ”é uma árvore pequena e ornamental devido a beleza de suas flores, ocorre nas regiões secas do brasil central o h oh o hho r r o h hho o o o o oglu o h h oglu oh h h o oh ho r r h co me co me h o ho h h o o oh oh figura . iridoides ( - ) isolados de tocoyena formosa tocoyena brasiliensis, conhecida popularmente por genipapinho, é outra espécie de rubiaceae, estudada por bolzani e colaboradores, tendo sua composição química relatada na literatura pela primeira vez. do extrato clorofórmico das folhas foram descritas as saponinas triterpênicas -o-β-d- quinovopiranosil ácido quinovico, -o-β-d- quinovopiranosil ácido cincholico, -o-β-d- glucopiranosil ácido quinovico e o éster do -o-β-d-glucopiranosil ácido quinovico como misturas binárias, com atividade moderada sobre as cepas de c. cladosporioides. o gênero rudgea é amplamente valli, m. et al. rev. virtual quim. |vol | |no. | | - | distribuído ao longo da costa brasileira, sendo que para algumas espécies há registros de uso medicinal. a espécie r. jasminoides além de chamar atenção pela sua beleza delicada é especialmente apreciada pelo aroma agradável de jasmin de suas belas flores brancas. Ácido canárico, um derivado triterpênico do tipo seco-lupânico, foi relatado pela primeira vez no extrato das folhas de rudgea jasminoides, além dos já conhecidos ácidos ursólico e oleanólico, de larga ocorrência no gênero. vários triterpenos e saponinas pentahidroxiladas ( - , figura ) de ocorrência menos frequentes no táxon foram isoladas de r. viburnioides. ho ho r r ho oh r r r ch ch h cooh ch h coo-glu h ch coo-glu ch h r oh figura . triterpenos e saponinas pentahidroxiladas ( - ) isoladas de r. viburnioides outro gênero de rubiaceae comum nos biomas brasileiros é chiococca. com cerca de espécies endêmicas do continente americano, ocorre desde os estados unidos da américa até o brasil. diversos usos medicinais são relatados para espécies de chiococca, sobressaindo-se como antiinflamatório e antiviral. chioccoca alba é a espécie mais usada na medicina popular como diurético e antiinflamatório figura . as raízes desta espécie são descritas em farmacopeias europeias desde o século . foi verificada a presença de iridoides ( - , figura ) nas raízes de c. alba, sendo que o seco-iridoide apresentou atividade moderada contra rs de saccharomyces cerevisiae. chioccoca alba valli, m. et al. rev. virtual quim. |vol | |no. | | - | o h h ho oho o h ho hho h h o h oho r r o o h h oho o h ho h ho h ho h o ho oh o oh ho r r och oh och och h och figura . iridoides glicosilados ( - ) isolados das raízes de chioccoca alba já o extrato das folhas de c. braquiata mostrou forte atividade antifúngica contra c. cladosporioides, e o fracionamento bioguiado levou ao isolamento de flavonoides e triterpenos que não mostraram atividade antifúngica significativa que justificasse a atividade potente observada no extrato bruto. neste estudo foi relatada a diminuição de atividade durante o processo de fracionamento, até a perda total da atividade antifúngica das substâncias puras isoladas, indicativos de um possível efeito sinérgico, deduzido após experimento de recombinação dos flavonoides puros isolados e aumento da atividade perdida no processo de purificação. outro aspecto particularmente valioso da diversidade molecular é a informação abstraída de inúmeras substâncias que se formam em determinados táxons, a partir de classes biossinteticamente distintas, podendo ser ferramentas valiosas no arranjo filogenético de determinado grupo. uma classe de metabólitos secundários de complexidade molecular e rara beleza são os alcaloides indolo mono terpênicos, considerado um excelente marcador quimiotaxonômico dentro de angiospermae, pelo fato de posicionar rubiaceae em gentianales ao lado de apocynaceae e loganiaceae, mas principalmente por permitir cladísticas de afinidades quimiotaxonômicas internas na família auxiliares na identificação taxônomica, muito complexa nos níveis hierárquicos de tribo, gênero e espécie. calycophyllum spruceanum é uma árvore endêmica da amazônia usada tradicionalmente para o tratamento de infecções, câncer e micoses (figura ). a decocção da casca é utilizada na medicina popular. desta forma, o extrato etanólico da casca de c. spruceanum foi estudado e diversos iridoides foram isolados. a subfamília cinchonoideae, na qual c. spruceanum está inserida, é caracterizada pelos alcaloides indólicos. a comparação da composição química desta espécie com outras morfologicamente relacionadas como chimarrhis revela grandes diferenças nos principais metabólitos secundários isolados. essas espécies são frequentemente dispostas erroneamente em outros gêneros, portanto estudos adicionais são úteis para a classificação taxonômica de rubiaceae, um táxon complexo. esses iridoides mostraram atividade tripanocida. valli, m. et al. rev. virtual quim. |vol | |no. | | - | figura . c. spruceanum, uma árvore endêmica da amazônia usada tradicionalmente para o tratamento de diversas patologias parâmetros apenas morfológicos não são suficientes para posicionar taxonomicamente diversas espécies em subfamílias e tribos na família rubiaceae devido à falta de informação sobre ocorrência geográfica e características morfoanatômicas em níveis mais baixos, como por exemplo, do gênero chimarrhis. assim, o perfil metabólico de diferentes espécies pode contribuir para o posicionamento taxonômico, especialmente para as que têm morfologia controversa, já que metabolitos secundários são expressões de evolução e adaptação de uma espécie. chimarrhis turbinata é uma árvore, popularmente conhecida como “pau de remo”, que cresce do caribe à américa do sul tropical, ocorrendo predominantemente em regiões amazônicas. os alcaloides indólicos monoterpênicos ( - ) isolados de c. turbinata (figura ) tiveram grande contribuição nos estudos de quimiotaxonomia da família rubiaceae. - esses alcaloides corroboram com a classificação feita por robbrecht, em que classifica chimarrhis como um gênero da tribo condamineae e subfamília cinchonoideae. os alcaloides indólicos corinanteanos ( - , figura ) isolados de c. turbinata revelaram afinidade desta espécie com cinchonoideae. nesta subfamília predomina a ocorrência de alcaloides indólicos, enquanto iridoides são exclusivamente encontrados na subfamília ixoroideae. , valli, m. et al. rev. virtual quim. |vol | |no. | | - | n h nh o h o o o h oh h oh h h ho h o ho n h n o oh o o h oh h oh h h ho ho ho n h nh o oh o o h oh h oh h h ho ho ho h n h n oo o h oh h oh h h ho ho ho o ho oh o n h n oo o h oh h oh h h ho ho ho o oh o n h n oh o figura . alcaloides indólicos monoterpênicos ( - ) isolados de c. turbinata n h nh o h o o o h oh h oh h h ho h o ho o oh n h n c h h r ho o o r r r ch h h ch n h n h o h oh h oh h h ho ho ho oho o n h n o o o o h oh h oh h h ho ho ho figura . alcaloides indólicos corinanteanos ( - ) isolados de c. turbinata além dos estudos de taxonomia, a avaliação do extrato etanólico desta espécie levou ao isolamento de diversos flavonoides glicosilados e de um dímero inédito com valli, m. et al. rev. virtual quim. |vol | |no. | | - | propriedade antioxidante. flavonoides são reconhecidos como a maior classe de metabolitos secundários com potencial antioxidante devido à alta capacidade de sequestrar radicais livres. estas propriedades são vitais para as espécies, pois funcionam como protetor natural contra as radiações ultravioletas, prejudiciais a várias formas de vida na terra. as propriedades antioxidantes dos flavonoides destacam esta classe como agentes potenciais nos processos inflamatórios, na hipertensão, câncer e doenças vasculares. o extrato etanólico das folhas e as substâncias isoladas foram avaliados quanto à propriedade antioxidante e alguns flavonoides se mostraram mais ativos que os padrões de referência. mais recentemente, chimarrhinina ( , figura ), com um novo esqueleto, foi isolada do extrato das folhas de c. turbinata. além da intrincada complexidade estrutural atribuída a uma nova junção c - c , configurando um esqueleto de neolignana completamente inédito, a presença de neolignana é um dado que carece de mais investigação no gênero. a estrutura do novo esqueleto c .c foi deduzida pelos dados espectrométricos, especialmente de ressonância magnética nuclear (rmn) bidimensional, permitindo a determinação de configuração relativa. estudos de modelagem molecular foram importantes para verificar que os dados de rnm são completamente compatíveis com a estrutura molecular inédita de . a nova substancia apresentou atividade antioxidante mais pronunciada que o padrão bht, um conhecido antioxidante para alimentos. oo o o ohho oh oho ho oh ho figura . nova lignana, chimarrhinina ( ), isolada de c. turbinata visualmente, os fungos endofíticos podem não ser tão belos como as flores de inúmeras espécies de plantas pertencentes ao táxon rubiaceae, porém possuem uma rica diversidade química, formidavelmente bela e útil por suas propriedades biológicas. o estudo de produtos naturais isolados de fungos é bastante promissor visto que esses compostos possuem propriedades terapêuticas já descritas e exploradas, como antibiótica, antifúngica e antitumoral. estudos químicos e biológicos de fungos endofíticos associados a espécies vegetais de cerrado e da mata atlântica são escassos, e, portanto, de grande interesse na busca de novas substâncias com propriedades farmacológicas. espécies de xylaria isoladas de palicourea marcgravii foram selecionadas para estudo devido à atividade antifúngica do extrato bruto nos fungos fitopatogênicos cladosporium cladosporioides e c. sphaerospermum, sugerindo presença de metabólitos com tal atividade. o estudo químico dos extratos de xylaria sp. levou ao isolamento da citocalasina d ( , figura ) com atividade antifúngica e interesse comercial. a produção de substâncias antifúngicas por espécies de xylaria indica valli, m. et al. rev. virtual quim. |vol | |no. | | - | que o fungo associado a p. marcgravii tem relação de simbiose que produz compostos antifúngicos contra possíveis fungos fitopatogênicos. em outro estudo, espécies de penicillium foram isoladas das folhas de alibertia macrophylla. o estudo de uma das espécies levou ao isolamento de diidrocumarinas ( - , figura ), obtidas pela primeira vez no gênero penicillium. esses compostos revelaram atividade antifúngica moderada contra c cladosporioides e c sphaerospermum e fraca atividade anticolinesterásica, mais uma vez mostrando que os fungos endofíticos são promissores na busca por compostos bioativos. n h o ch h oh h h o o o h oh figura . citocalasina d ( ), isolada dos extratos de xylaria sp o oh oh o o o o o oh o oh figura . diidrocumarinas ( - ) isoladas de penicillium sp. a beleza ornamental das espécies de rubiaceae é bastante evidente e conhecida, porém a beleza da diversidade química ainda é muito pouco explorada. neste capítulo foram particularizados metabólitos secundários de várias classes, mas de uma única família vegetal, evidenciando a riqueza molecular da biodiversidade que continua sendo uma fonte de inspiração constante para várias áreas do conhecimento, especialmente para a química, exemplificados pela síntese orgânica e química medicinal; para a biologia, ilustrados pela ecologia, fisiologia, entre outras áreas. assim, tanto as espécies vegetais quanto os fungos endofíticos associados são fontes abundantes de novas estruturas químicas, de beleza e criatividade inimagináveis. agradecimentos os autores gostariam de agradecer à fundação de amparo à pesquisa do estado de são paulo (fapesp), conselho nacional de desenvolvimento científico e tecnológico (cnpq) e coordenação de aperfeiçoamento de pessoal de nível superior (capes). referências bibliográficas valli, m.; pivatto, m.; danuello, a.; silva, d. h. s.; castro-gamboa, i.; cavalheiro, a. j.; araújo, a. r.; furlan, m.; lopes, m. n.; bolzani, v. s. the tropical biodiversity: has it been a potential source of secondary valli, m. et al. rev. virtual quim. |vol | |no. | | - 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[crossref] oliveira, c. m.; silva, g. h.; regasini, l. o.; zanardi, l. m.; evangelista, a. h.; young, m. c. m.; bolzani, v. s.; araujo, a. r. bioactive metabolites produced by penicillium sp. and sp. , two endophytes associated with alibertia macrophylla (rubiaceae). z. naturforsch. , , . http://dx.doi.org/ . /s - ( ) - http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /s - ( ) - http://dx.doi.org/ . /np m http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /np m http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /s - http://dx.doi.org/ . /np http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /s - abstract resumo referências bibliográficas symmetry and beauty in plato symmetry , , - ; doi: . /sym symmetry issn - www.mdpi.com/journal/symmetry article symmetry and beauty in plato david r. lloyd school of chemistry, trinity college, dublin , ireland; e-mail: boblloyd@waitrose.com received: february ; in revised form: march / accepted: march / published: march abstract: plato writes about beauty in many of his dialogues, particularly in the symposium, but he has no word equivalent to our "symmetry", and this concept was not then formalised. nevertheless, there are indications that some aspects of the concept were understood, if only intuitively. plato has a very abstract concept of beauty, and when he uses "beauty" to characterise the so-called "platonic solids" in the timaeus, he seems to be emphasising at least their regularity. it can be argued that the way in which he specifies the detailed construction of the solids is remarkably close to a modern description in terms of (point) symmetry. for plato, something of our symmetry is included in what he means by beauty, and the long mathematical approach to symmetry starts with the timaeus. keywords: history; symmetry; proportion; plato; timaeus; elements . introduction "euclid alone has looked on beauty bare" wrote edna st. vincent millay, twice in one stanza [ ]. it is not clear what led her to this idea, and it would be rather difficult to check. it can hardly have been the beauty of euclid's greek, which has a rigid formulaic structure, with the catchphrases lego hoti (i say that....) and hoper edei poiẽsai (qed) echoing through thirteen volumes and two and a quarter millenia. it may be that here as elsewhere millay is being ironic. there is of course a grandeur to euclid's concept of summarising and systematising all known geometry, but there is not much evidence of this being driven by aesthetic considerations. much of euclid was derived from earlier work in plato's academy [ ], particularly that of theaetetus and of eudoxus. indeed it is possible to see much of the structure of the elements as a slow build- up to the final constructions of book in which the 'platonic solids" are built up in an extraordinary intellectual tour de force. nevertheless if anyone has a claim to have first seen true mathematical beauty, it must be either plato, who also writes open access symmetry , particularly beautiful greek, or his friend theaetetus. it is almost certain that it is the work of theaetetus on the regular solids which forms the base on which plato builds the second half of his dialogue timaeus, which is discussed below. there is no surviving written record from theaetetus, though it is likely that books and of euclid are largely his work [ ]. by default the regular solids have been called platonic; perhaps theaetetic would be more accurate, but it does have some pronunciation problems. a historical account such as the one i am attempting here would normally spend some time in setting the wider context of symmetry. however two excellent accounts of the development of symmetry from the earliest history, through the work of galois, abel and lie and on to modern research, have appeared recently. these are "why beauty is truth : a history of symmetry” by ian stewart [ ], and "finding moonshine" by marcus du sautoy [ ]. these works have very different approaches; either may be consulted for a more extended view than the one given here. in addition to discussing plato and theaetetus, du sautoy’s book illustrates some very early examples of symmetric objects, some prehistoric, which may have constructed for what we would call ‘aesthetic’ reasons. there is also a very useful short summary in artmann [ ], where the relation to ideas of beauty is also discussed briefly [ ]. the next two sections are to some extent expansions of artmann's comments. . symmetry, and the use of the word "summetria" by plato the relation of symmetry and beauty is not an easy subject to address, and my title, simple though it appears to be, may have implied too much. there is an asymmetry hidden in it, since although plato has a great deal to say about beauty, most notably in his discourse symposium, he has nothing direct to say about symmetry as we understand this word nowadays. this is hardly surprising, since there was no word at that time which conveys this meaning. hon and goldstein have argued [ ] that our modern use of the word 'symmetry' was unknown until legendre developed the concept in the th century. some translations from classical greek do indeed use this word, or the associated adjective symmetric, but this is unfortunate, and can be misleading. the greek noun summetria, and the associated adjective summetros, both of which are used quite frequently by plato in the timaeus, (though rarely elsewhere) mean literally 'the same measure' or 'of the same measure'. the principal uses of the noun are to convey the senses of 'commensurability' or of 'proportion' [ ]. the adjective has a number of uses, including connections with pitch and rhythm in music, but the principal meaning is ‘commensurable’, having a common measure. a citation for summetros from the principal classical greek dictionary by liddell, scott and jones [ ] makes the point well: "in mathematics, having a common measure; freq. denied of the relation between the diagonal of a square and its side." in our terms, the incommensurability here is the irrationality of √ . a more sophisticated version is also cited with this comment, from plato's theaetetus. this shows the main character as a young student who is already working on generalising this incommensurability problem, and classifying all integers according to whether or not they have an integer square root. symmetry , despite the lack of a word, there are aspects of greek geometry where symmetry is implicit. the facts that the diameter of a circle splits it into two equal halves, and that the basal angles of an isosceles triangle are equal, are assumed to be "obvious", but only because of the symmetry of these examples. not long after plato, pappus of alexandria produced a proof of the second of these, which used to be called the ‘pons asinorum' (euclid's elements, book , proposition ). coxeter [ ] points out that this proof from pappus is equivalent to invoking the symmetry operations of reflection or rotation of the diagram. thus, even though nobody was in a position to formalise the concept of symmetry, the mathematical importance of it was beginning to emerge in plato's time, and there is another example of this implied rotation or reflection operation in one of plato's earlier dialogues, the meno, which is discussed below. at one point in the timaeus ( e) [ ] plato may even be referring directly to the reflection symmetry of the normal human body, by taking as an example someone who has "one leg longer than the other". (the translations here and elsewhere for the timaeus are from waterfield [ ]). this, plato says, would be ametros, without measure. one translation has “disproportionate”, another gives “dissymmetric” which seems more appropriate here. however it should be noted that the text is ambiguous, and uses an unusual word which could mean that both legs are too long, and hence out of proportion with the rest of the body (the first meaning is the one given in reference [ ]). whichever is the true meaning, in the context of the following section it is important that plato has been discussing proportion and beauty, and says that such a deformity, being out of proportion, would be ugly. . beauty in plato many of the dialogues refer to this concept, and only a brief sketch is appropriate here. before describing the approach of the symposium, it is worth quoting the philebus, ( c-d) where, as usual, plato writes as if socrates is providing the ideas, though in reality it is probably plato's thinking that we get. 'socrates' says: "i do not mean by beauty of form such beauty as that of animals or pictures, which many would suppose to be my meaning; but, says the argument, understand me to mean straight lines and circles, and the plane or solid figures which are formed out of them by turning-lathes and rulers and measures of angles; for these i affirm to be not only relatively beautiful, like other things, but they are eternally and absolutely beautiful, and they have peculiar pleasure, quite unlike the pleasures of scratching." although socrates is using real man-made objects, which are inevitably imperfect, as his examples, his principle of beauty here refers to the eternal perfect forms which underlie these objects, and the surrounding text from which this is taken confirms this. notably, all his examples of true, absolute beauty here have high symmetry in the modern sense. the "plane figures" here are probably the regular polygons; it is clear from euclid that the study of these was important in greek geometry. the mention of turning on a lathe suggests that plato/socrates considers cylindrical symmetry to be particularly beautiful, and this correlates well with the use of spherical symmetry in the timaeus, symmetry , described below. according to legend, the entrance to plato's academy was decorated with a slogan usually translated as "let no-one ignorant of geometry enter". similarly, it was said that for plato, "god is always doing geometry". although these quotes are probably mythical, they illustrate something very important, that geometry was considered to be one of the highest of studies. plato's god, as we will see, constructs the entire universe on geometrical principles, but a geometry which gives highly symmetrical results, which would certainly satisfy the conditions of beauty laid down here by socrates, since it generates the 'solid figures' mentioned. the dialogue symposium is mainly concerned with eros, love. the translation used here is by griffith [ ]. some real characters of plato's time are given speeches which illustrate various aspects, all with a strong sexual context, mostly homosexual, though the one from a doctor takes eros as a principle underlying all of nature. the final major speech is given to socrates, who begins in his usual style, taking apart the arguments of the previous speaker; in particular he attacks the idea that eros is beautiful. however, in sharp contrast to his usual practice, socrates presents his arguments as something he learnt from someone else, and, remarkably for the time, from a woman, diotima. diotima begins by downgrading eros, who, she argues, far from being beautiful, is ugly, but seeks beauty. thereafter the ground shifts subtly from a description of homoerotic love into a discussion of beauty, and describes higher and higher levels of a generalised beauty. initially the student of beauty may start from the beauty of the body of a particular lover, but then he should move on to become a "lover of all physical beauty". following this, he should learn to prefer mental beauty to physical beauty, and thence to "see the beauty of different types of knowledge", and to "gaze upon the limitless ocean of beauty". even this is not the highest level, but if the student (socrates) persists, he may "come to the final end and goal of this education. then suddenly he will see a beauty of a breathtaking nature, socrates, the beauty which is the justification of all his efforts so far. it is eternal, neither coming to be nor passing away, neither increasing nor decreasing. moreover it is not beautiful in part, and ugly in part, nor is it beautiful at one time, and not at another........it exists for all time, by itself and with itself, unique...." this extraordinary rhapsody, not given in full here (see a- a), makes it very clear that for plato, beauty is one of the highest ideals. it does have a connection to simple physical appearance, since " all other forms of beauty derive from it ", but goes far beyond that. it incorporates knowledge in all its forms, including, as we saw in the philebus, mathematical objects, and comes very close to plato's highest ideal, the form of the good. plato's prose-poem overwhelms the poem of millay with which this article began, and clearly she should have cited plato rather than euclid. . the meno argument in the dialogue meno, plato shows socrates trying to demonstrate that memory is built-in, from a previous existence, the so-called 'theory of recollection'. part of his argument is that a simple slave- symmetry , boy, with little or no mathematical education, can be shown to have an innate understanding of the principles of the advanced science of geometry. with what seems to us a set of rather leading questions, he sets out to demonstrate that the boy has a knowledge of how to generate a square of double the area of a starting square. this is of course, closely related to the question of incommensurability mentioned above, though socrates does not take the matter so far. beginning with the starting square, socrates goes through a long exercise of getting the boy to count up various numbers of equal squares, ultimately demonstrating that the side length of the doubled square cannot be an integral multiple of that of the starting square. as this goes on the original diagram of one square becomes a matrix of equal squares. then comes the punch line of the argument. we the readers are meant to understand that socrates draws in a diagonal across one of these squares. socrates: "and does not this line, reaching from corner to corner, bisect each of these spaces?" the unfortunate slave-boy who is being made to jump through hoops replies "yes" to this question. apparently this answer is 'obvious' and needs no proof, but it is only obvious because of the symmetry of the divided square, and socrates is using the rotation or reflection symmetry of the construction for his demonstration. from here it is only necessary to do this four times in the matrix of squares which has been built up during the earlier part, and a doubled square appears, assembled from four halves, and rotated by º from the originals. we will encounter this -fold symmetric structure again in the following section. plato makes no reference to beauty in this section of the meno, but in the timaeus, symmetry and beauty are brought together in a way which has already been hinted at in the citation above from the philebus. . the timaeus this dialogue, written in his later years, is plato's presentation of a 'theory of everything'. (much more detailed expositions than can be given here can be found in [ , , ]). in the first part plato shows a divine being, his 'demiurge' or 'craftsman', taking on a chaotic universe and bringing order into it. this is not a creatio ex nihilo, but a working with what is available. the demiurge makes the universe according to an ideal pre-existing model, and builds it to be the best possible one; it is to be both beautiful and good. plato wastes no time on defining what he means by these; probably he expects his readers to be familiar with both the symposium and the republic. two principles are of particular significance for the demiurge, that order "is in all ways better" than chaos ( a), and that similarity is "incomparably superior to dissimililarity" ( b). all the stuff available to the demiurge is combined in ratios which are based on the mathematics of music, the harmonic series ( b-c). the combined material is then used to construct the macrocosmos, with a spherical earth at the centre of a spherical universe. his definition of spherical form ( b) has an implication of working on a lathe [ ], paralleling the citation from the philebus in section above, but he also gives a more abstract definition, “equidistant in all directions from its centre to its extremes.” the very interesting reason which plato gives for the use of the sphere is that: symmetry , "there is no shape more perfect and none more similar to itself." ( b) the rather odd phrase " none more similar to itself" has not attracted much comment in modern studies. although plato gives us no more information on this, it seems plausible that he is thinking of a cube, for instance, as being 'similar to itself', but this is only true when it is rotated through specific angles about particular axes, e.g. º for the -fold axes, i.e it is regular. i will return to the concept of regularity below, but it is clear that plato considers that the sphere is the most perfect shape because there is a multiplicity of ways in which it can be made similar to itself. indeed " none more similar to itself" is remarkably similar to our description of spherical symmetry as possessing an infinite number of rotation axes. it is also interesting that he says here that the sphere “includes all shapes within itself”. here “all shapes” is probably to be interpreted as meaning the five regular solids, and “includes” refers to the fact that they can all be inscribed within a sphere; there is a specific reference to this point for the tetrahedron later, at ( a). the spherical universe rotates on two inclined circles, much as in late mediaeval and renaissance "armillary sphere" models, and with this structure plato begins to give a description of the complex motions of the sun, moon and planets through the sky. the description is of course very incomplete, but it provided a framework for later greek astronomers [ ]. the second part of the dialogue goes back to the beginning again and describes in more detail the nature of the stuff with which the demiurge has made the universe. the traditional fire, air, water and earth are used ( c), but whereas earlier thinkers had considered these to be primitive, true 'elements', timaeus/plato is rather scornful of this and insists that he can go to a deeper level ( c). the 'elements' are each made up as assemblies of particles having a particular shape, and the shapes are those of the regular solids discovered earlier by theaetetus. these shapes are, for plato, kallistos, "most beautiful" ( e and following); by using these, the demiurge can construct the most beautiful universe possible. the nature of theaetetus' discovery has been analysed by waterhouse [ ], who argues that there are a number of important aspects. one is the elegant proof that there are five and only five such bodies. the other really significant discovery is the concept of regularity, that all side lengths, side shapes and angles are equal. this idea had to be discovered by someone, and waterhouse makes a good case for theaetetus. waterhouse does not mention plato's phrase 'similar to itself', but this could serve very well as a definition of regularity, remembering that for plato/timaeus, similarity is "incomparably superior to dissimilarity". theaetetus is believed to have discovered the icosahedron, and, according to an ancient tradition discussed by waterhouse, also the octahedron. many commentators have been sceptical that the octahedron discovery could be so late, particularly sir thomas heath, who comments that the egyptians, experts on pyramids, could surely have imagined putting two together, and an octahedron "is only a double pyramid with a square base' [ ]. (a somewhat similar comment appears in du sautoy [ ]). symmetry , however, this completely misses waterhouse's point about regularity. the height of most egyptian pyramids is less than half the diagonal of the base, and in modern terms, heath's imagined egyptian construction has only d h symmetry. theaetetus's discovery means that if, and only if, the dimensions of such an object are adjusted correctly, then a previously unrecognised regular figure, one which is 'similar to itself', the regular octahedron, appears. bipyramids might well have been constructed or visualised at earlier times, but there would have been nothing special about any of them before the concept of regularity had been recognised. given the elegance both of the concept of regularity and of the proof that there are only five, and the discovery of one or possibly two new regular solids, it is not surprising that plato, with his elevated sense of beauty shown in the philebus and in the symposium, should find this set of solids to be supremely beautiful. he uses the tetrahedron as his unit of fire, the octahedron for air, and the icosahedron for water, and because all of these are defined by the same triangular faces, he can allow interconversions between these elements. the fourth element earth is assigned to the cube, which has square faces and so cannot interconvert with the others. the remaining solid, the dodecahedron, is assigned to the whole universe, as some sort of decoration ( b). the universe has already been described as spherical, so the -sided 'decoration' may be referring to the zodiacal signs [ ]. compelling evidence that plato is thinking in terms of regularity appears in the way in which he analyses the sub-structure of the units of his 'elements'. he argues that the fundamental units are not the bodies themselves, and not even the faces mentioned above, but particular right triangles, ones which in our language have sides of length ( , , √ ) and ( , √ , ), i.e. isosceles with angles of ( º, º, º) and scalene with angles ( º, º, º). using the scalene triangle, he gives very precise specifications of how the equilateral faces of the first three elements are to be constructed ( d-e). the final result of the specification is shown in figure b. the assembly instructions begin by joining two scalene triangles "at their hypotenuses" (kata diametron), so that these form the long diagonal of a quadrilateral, then this is done three times, generating three such quadrilaterals. finally the three are joined " so that all the hypotenuses and short sides converge at the centre." figure . constructions of equilateral triangles; a) an apparently simple species; b) plato's specification at timaeus d-e. symmetry , as we have seen, plato did not have our language of symmetry, and to what extent he was aware of the underlying concepts is difficult to assess. nevertheless his description of the construction draws attention, first to the mirror symmetry of the pair, and then to the three-fold axis of the final composite equilateral triangle. by adopting this construction, plato has preserved the full symmetry of an undivided equilateral triangle. a rather similar comment has been made by brisson [ ] who notes that "on peut cependant penser que, dans le cas du carré et dans celui du triangle équilatéral, platon veut trouver un centre de symétrie axiale." even if plato was not conscious of symmetry as we understand it, if we follow waterhouse [ ], the idea of regularity in three dimensions would have been available. taylor [ ] connected regularity with plato's kallistos, "most beautiful", as long ago as , and this connection is discussed in some detail by artmann and schäfer [ ]. their view that kallistos, when applied to the solids, is principally a description of regularity, is that adopted here. having constructed the equilateral triangle, plato then assembles four of these into a tetrahedron, eight into an octahedron, twenty into an icosahedron. since he has used composite triangles with the full symmetry of undivided triangles, the bodies he assembles from these have the true symmetries td, oh and ih of the regular polyhedra [ , ]. in language which might have been easier to explain to plato, he has preserved the regularity of the bodies by using his composition of the triangles. that this is no trivial point can be seen from the fact that most modern commentators have been puzzled as to why plato does not use an apparently simpler composition, that shown in figure a, for his equilateral triangles. cornford [ ] had suggested that plato's intention was that many different constructions were to be understood for the equilateral triangle, and that the text gives us only a 'sample' construction. he proposed that in each case plato's 'sample' construction is for the second member of a series; the first would use only two of the constituent elementary triangles, figure a. the higher members of this series are then generated using a pair of geometrical constructions from euclid. this proposal received wide acceptance in the literature in english. however, artmann and schäfer [ ] pointed out that a, the first member of cornford's series, and also the third, have lost the symmetry of the equilateral triangle. corrrespondingly, such a triangles cannot generate bodies which are truly regular polyhedra. furthermore, a triangles can be assembled into polyhedra with a variety of different orientations, giving a multiplicity of varieties for each individual element. in chemical terms, use of the a triangles would generate bodies which have many isomeric forms [ , ]. this is in clear opposition to plato's requirement, at e, that each of the bodies is "of a single kind" (kath' hen genos); this requirement of course follows automatically if the triangles have been made up according to his specification (figure b), since the bodies are then regular. plato's construction of the equilateral triangle amounts to a tripling of a smaller triangle [ ]; if two of the scalene triangles are connected as in figure a, the area of this equilateral is one third of the b triangle. in the same way, plato constructs his cubes (earth) with squares made up from four of his elemental isosceles right triangles, assembled exactly as in the diagram which socrates drew for the slave-boy in the meno to demonstrate the doubling of the square. since such composite squares have symmetry , full -fold symmetry, the cubes constructed from them are true regular cubes. this of course, would not be so if the squares were made up by the ‘simpler' method of joining only two triangles along the hypotenuse. in addition to the emphasis that the bodies are kallistos, most beautiful, plato also describes the scalene triangles used for constructing three of them in the same way. artmann and schäfer [ ] have discussed this description for the triangles. they conclude that it can be explained by the specific proportions of the composite triangle in figure b. these follow a geometric proportion argument which plato has already used at c- a, and this can only be true if º, º, º scalene triangles are used. it is very likely that this is indeed a part of plato's reason for calling the triangles kallistos. however, immediately following this description at c, plato states that his reason for this is "too long a story" (logos pleiôn). this cannot be true of the proportion argument, which he has already set out in detail. the problem of keeping the length of the discourse within reasonable limits also occurs at c-d, where the details of the motions of the celestial bodies are said to be so complex that "to describe all this without visible models would be labour spent in vain". a similar comment would apply at least as strongly to any attempt to demonstrate that the regularity of a body made up from plato's composite triangles is unchanged from that of the simple regular body of the same form. an appropriate mathematical language for this was not available, and to attempt the explanation of such a point verbally would have been a very long task. however, examination of appropriate models immediately makes it clear that the regularity of a body made up from the composite b equilateral triangles is indeed that of the simple body. as an example, a model of an octahedron made in this way is shown in figure . figure . a model octahedron constructed from b equilateral triangles, according to plato’s description. using such models, whether physical or imagined, it would have been evident to plato that bodies constructed in this way are completely regular, kallistos, even though an attempt to explain the argument in writing would have been tedious, a logos pleiôn. a principal reason for labeling the º, symmetry , º, º triangle as kallistos is then that this triangle, and only this one, allows these symmetric constructions [ ]. . final remarks symmetry runs through much of modern science, and for many of us it has become almost automatic to respond to the mathematical aspect only; we find a new structure and we reach for our character tables. nevertheless, the history of the subject is intertwined with a human response to beauty, and this has almost certainly helped to drive the subject forward to its present high sophistication. the theme, that the universe has been constructed to be the most beautiful possible, runs throughout the timaeus. however, plato's concept of beauty is a very refined one, and it is clear from the symposium citation that this is not merely a matter of outside appearance. according to stewart and golubitsky [ ]: "there is no evidence that either plato or euclid possessed a mathematical formulation of the concept of symmetry; to them the appeal of the regular solids seems to have been primarily aesthetic." the first part of this is not particularly surprising, given the lack of an appropriate language. however, if "aesthetic" refers to outward appearances only, plato might have taken exception to the remark. for him there could be no dichotomy between the mathematical aspects and the beauty of these objects. aristotle relates a story of a large audience attending a lecture of plato on "the good", only to be completely baffled when the entire lecture was on mathematics. for plato, his kallistos description is a mathematical description. clearly he did not understand symmetry as we do, but when he speaks of the units of his elements as being "most beautiful", it seems very likely that he means at least something like our regularity. although there is evidence of earlier construction and use of symmetric objects [ , ], it is with plato, presenting his own ideas, but also relying heavily on theaetetus, that we can find the first hints, expressed in the language of beauty, of the mathematical ideas which ultimately lead on to our modern symmetry theory. . acknowledgements i thank p. daunt for discussions on the symposium, and two referees, whose input has improved the presentation at several points. references and notes . millay, e.st.v. euclid alone has looked on beauty bare. in the norton anthology of poetry, th edition; ferguson, m., salter, m.j., stallworthy, j., eds.; norton: new york, ny, usa, ; p. . . artmann, b. euclid-the creation of mathematics; springer: new york, ny, usa, ; pp. - , - , . . stewart, i. why beauty is truth : a history of symmetry; basic books: new york, ny, usa, . . du sautoy, m. finding moonshine; fourth estate: london, uk, . . reference [ ], ch. . symmetry , . reference [ ], pp. - . . hon, g.; goldstein, b.r. legendre's revolution ( ): the definition of symmetry in solid geometry. archive for the history of exact sciences , , - . . both of these words are given as definitions of summetria in reference [ ]. however, it has been pointed out by a referee that in euclid, ‘commensurability’ and ‘proportion’ have quite separate uses, the first referring to a relation of two segments, the latter to a relation of four quantities, as in the proof in proposition . that the areas of two triangles of the same height are in the ratio of the lengths of their bases. this is discussed in reference [ ], ch. . . liddell, h.g.; scott, r.; jones, h.j. a greek-english lexicon; clarendon press: oxford, uk, . . coxeter, h.s.m. introduction to geometry; wiley: new york, ny, usa, ; p. . . numbers are given for references to the texts of plato's works; these are provided in almost all printed versions, both for the original greek and for translations. . waterfield, r. plato: timaeus and critias, with introduction and notes by gregory, r.; oxford university press: oxford, uk, . . griffith, t. symposium of plato; university of california press: berkeley, ca, usa, . . zeyl, d. plato's timaeus http://plato.stanford.edu/entries/plato-timaeus/ (accessed march ). . zeyl, d. plato: timaeus; hackett publishing company: indianapolis, in, usa, . . brisson, l. platon- timée, critias; flammarion: paris, france, ; note , p. . . gregory, a. eureka! : the birth of science; cambridge university press: cambridge, uk, . . waterhouse, w.c. the discovery of the regular solids. archive for the history of exact sciences , , - . . heath, t. the thirteen books of euclid's elements; 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under the terms and conditions of the creative commons attribution license (http://creativecommons.org/licenses/by/ . /). gg_gameecobehav_ .dvi institute for empirical research in economics university of zurich working paper series issn - working paper no. the α-beauty contest: choosing numbers, thinking intervals enrico de giorgi and stefan reimann march the α-beauty contest: choosing numbers, thinking intervals∗ enrico de giorgi and stefan reimann† first draft: th june this version: th march abstract the -shot α-beauty contest is a strategic game under bounded rationality conditions, where equilibrium is approached if the game is played iteratively sufficiently many times. experimental data of the -shot setting show a common pattern: the spectrum of announced numbers is a superposition of a skew background distribution and a regime of extra ordinarily often chosen numbers. our model is capable of quantitatively reproducing this observation as well as the convergence towards equilibrium in the iterative setting. the approach is based on two basic assumptions: .) players iteratively update their recent guesses in the sense of eductive reasoning and .) players estimate intervals rather than exact numbers to cope with incomplete knowledge in non-equilibrium. the width of the interval is regarded as a measure for the confidence of the players’ respective guess. it is shown analytically that the sequence of guessed numbers approaches a (finite) limit within only very few iterations. moreover, if all players have infinite confidence in their respective guesses, the asymptotic winning number equals the rational nash equilibrium , while if players have only finite confidence in their recent guess, the winning number in the -shot setting is strictly larger than . our model is also capable of quantitatively describing the “path into equilibrium”. convergence is shown to be polynomial in the number of rounds played. the predictions of our model are in good quantitative agreement with real data for various α-beauty contest games. keywords: experiments, α-beauty contest, beliefs. jel classification numbers: c , d . ssrn classification: behavioral finance; experimental studies. ∗the authors are grateful to ernst fehr and thorsten hens for valuable discussions. financial support from the national centre of competence in research “financial valuation and risk management” is grate- fully acknowledged. the national centers of competence in research are managed by the swiss national science foundation on behalf of the federal authorities. †institute for empirical economic research, university of zurich, blümlisalpstrasse , -zurich. e-mail: degiorgi@iew.unizh.ch, sreimann@iew.unizh.ch introduction and overview of results ever since keynes ( ) the α-beauty contest has served as an example for a strategic game under bounded rationality conditions to cover elementary features of price forma- tion. the α-beauty contest game is described by nagel, bosch-domènech, satorra, and garca-montalvo ( ) as follows. “a certain number of players each chooses simultane- ously a decimal number, let us say, from the interval [ , ]. the winner is the person whose number is closest to α times the mean of all chosen numbers, where α < is a predetermined and known number. the winner gains a fixed prize. if there is a tie, the prize is split amongst those who tie or a random draw decides the winner.” being in an equilibrium would imply that each player’s belief is consistent with what all the other players actually plan to choose. in fact, as nagel ( ) clearly demonstrated, the game theoretic nash equilibrium is generally not observed in the -shot “α-beauty contest”, rather than is approached after sufficiently many rounds in the iterative setting, i.e. in the presence of communication. field experiments were conducted to estimate the behavior of probands when playing the guessing game in different settings (nagel , nagel and duffy ). the number of probands in controlled laboratory experiments is naturally constrained to an order of magnitude of only. hence corresponding outcomes are strongly influenced by individual behavior and may not cope for typical properties generated by the game. since we are interested in such typical properties, we first refer to studies with a much larger set of players such as the newspaper experiments conducted by nagel, selten, and thaler. for an overview, see nagel, bosch-domènech, satorra, and garca-montalvo ( ), where also a survey of experiments on the -shot guessing games can be found. figures and are two samples obtained from an experiment done by the german newspaper “die zeit” in and the spanish newspaper expansion, respectively (nagel, bosch-domènech, satorra, and garca-montalvo ). figure : the -shot guessing game played by approximately probands. data are from the experiment done by the german newspaper “die zeit” in . figure : the -shot guessing game played by the spanish newspaper espansion. data are taken from nagel, bosch-domènech, satorra, and garca-montalvo ( ). game theory predicts that if all players had identical beliefs and were perfectly ratio- nal, and if each player knows that all others were also perfectly rational, then would be the unique (stable) solution, in the sense of a game theoretic nash equilibrium. hence, under these conditions, it wold be rational to choose as the number to be announced. as experiments show, most players do not behave according to this. in fact, if only one player assumes that at least one player is irrational, then it is rational not to choose as the proposed winning number. the rational regime in figure , α = / , ǫ = k ..∞ χk table : the rational regime calculated according to our model, see next section. there are three main observations drawn from experimental data: the first observation is that the winning number observed is approximately equal in different (comparable) ex- periments. the second observation is that the spectrum of numbers announced is a super- position of a broad and highly skewed distribution and a collection of numbers {χ , χ , ..}, which are extraordinarilly often chosen. we call the set of these numbers the “rational regime” (see table ). while the skew distribution reflects the players’ uncertainty about other players’ rationality, the rational regime represents different depth of thinking of play- ers. the third observation is that equilibrium is established after a sufficient number of iterative rounds (see figure ). a reasonable model has to consistently explain these facts. we start by considering the -shot game setting. the strategy chosen by one individual crucially depends on her guess about strategies of the others, e.g. on the distribution of strategies played at that time by others. because of the lack of mutual consistency away from equilibrium, individual beliefs might differ from each others actual plans and are strongly based upon their individual recent hypothesis. hence it is natural to assume that all players have minimal prejudice about other players guesses. in this situation, strategies and thus guesses are expected to be heterogenous over the players’ population and context dependent. authors including nagel ( ), stahl and wilson ( ), ho, camerer, and weigelt ( ), costa-gomes, crawford, and broseta ( ) proposed the idea that all k-step players think that all others are k − step players. this assumption was weakened by camerer and coworkers (see for a review camerer ), claiming that all k-step players have an accurate guess about the relative proportion of players who are thinking k′ < k levels. camerer proposed that this distribution is poisson with intensity τ . this assump- tion also allows for taking into account that there are other players performing at most the same levels of thinking (camerer, ho, and chong ). it was found that τ varies between . and about . in -equilibrium games, while most of players perform . thinking steps. in most approaches numbers, let them be integers or reals, are considered as the fun- damental entities for individual choice of strategies. it is well-known that the result of a calculation essentially depends on the choice of the set of elements, the corresponding operation is defined on. of course it is not canonical that numbers have to be chosen for computation. other entities might be considered. intervals rather than numbers might be chosen to scope with the uncertain knowledge about others away from equilibrium. this fact invokes the key hypothesis of our model: “strategy choices rely on estimates on intervals rather than numbers!” a strategy thus is to choose an interval within the range of an admissible number ac- cording to which then the guess is calculated in the sense of a best reply. as an example: if a player guesses that the winning number is about , then the interval chosen might be [ , ]. without any further knowledge, the assumption is that each agent has minimal prejudice in that all numbers in this interval are regarded equally probable, while also all admissible intervals are equally likely. this assumption represents the rational guess of a player that all others are bounded rational or even irrational (plot ). we will propose an elementary model for the -shot setting of the guessing game which is played by a large number of subjects performing k levels of thinking (for details see section ). thereby we allow for infinite many levels of thinking, because a limit concerning depth of thinking is neither known nor a priori given. fundamental assumptions are : (i) each individual estimates intervals rather than numbers! this assumption is actually an assumption about the choice of strategies, see above; (ii) each individual successively updates his guessed number according to his recent be- lieve and hence generates an infinite sequence of guessed numbers during k iterations! this is actually to assume the mechanism of eductive reasoning. our model has explicit parameters m , n and α, where m is the number of players, n characterizes the set of alternatives and α is often is chosen to be / or / , as well as an implicit one ǫ. this parameter ǫ can be regarded as a measure for the confidence of an agent in her recent guess in the sense that the larger ǫ is, the less confident is the player. as we will discuss in the next section, the parameter ǫ is introduced to explain the skew distribution of guessed numbers observed in the experimental results. it is shown under very weak assumptions, i.e. ≤ α and ≤ ǫ ≤ that the expected (asymptotic) winning number y∗ in the -shot game yields y∗ = n ǫβ − β ( − ǫ) , ≤ α, ǫ ≤ where β = α m− m−α is approximatively equals to α for m , the number of players, large enough. the asymptotic expected winning number y⋆ is therefore unequal to unless α = or ǫ = , while y∗ = n/ if α = and ǫ = . it is shown that the sequence of guessed numbers converges to a stationary value, see proposition . this result was first obtained by reimann ( ) for a discrete set of alter- native and unlimited many players. it is shown that the asymptotically expected guessing number is strictly larger than if and only if intervals have positive width. the individual width can be regarded as a measure for the confidence a player has in her guess, i.e. the smaller the interval width the more confident is the player that her guess is correct. hence, if individuals have a finite degree of confidence in their individual belief, i.e. the intervals chosen have non-zero width, the system reaches a stationary state which is not the game- theoretic equilibrium. the nash equilibrium is obtained in a -shot setting if and only if the width of the confidence interval is . in other words the nash equilibrium would be played if and only if all players would assume that all other players are also rational. the convergence is rapid, i.e. within only thinking steps the guessed number (approximately) equals the corresponding stationary value for usual choices of the parameter α and ǫ. this property of rapid convergence allows us to consider the iterative game setting using the model proposed for the -shot setting. we further deduce the distribution of numbers announced in an ensembles of players with heterogenous believes. a reasonable model of the α-beauty contest must also explain the path towards equi- librium. in the second part of the paper we extend the previous model of the -shot game setting towards an iterative setting with t rounds. in the iterative setting, the game is played for several rounds - with the same rules - , while between rounds the winning number of the respective last round is made public, i.e. before playing the next round figure : the iterated guessing game: experimental data (red circles) show a log-linear relationship (blue line) between the winning numbers announced after each round and the number of rounds. the data are from an experiment conducted at the university of bergen, norway, . all players are informed about the resulting winning number of the previous round. if agents would be completely rational, communication would not have any impact. in the contrary, experiments show that communication does have a strong impact in that during only a very few rounds the winning number drops down to . this convergence should not be confused with the convergence within thinking steps in the -shot setting. in fact, the iterative game has two dynamical levels: the “fast” dynamics within one round and k levels of thinking and the “slow” dynamics over rounds. since convergence in thinking levels steps is fast, it is a good approximation to assume that at the end of each round the corresponding stationary value is announced. our model predicts that in an iterative setting the sequence of winning numbers drops to rapidly according to ln y∗(t) = ln y∗ + t ln ( ǫ − β ( − ǫ) ) . this linear relationship is in good agreement with real data, as shown in figure , which presents results from the iterated guessing game conducted at the university of bergen, norway. outline of the basic model the setting is as follows. there are µ = , . . . , m < ∞ agents or players, who choose a number xµ ∈ a := [ , n ], where n < ∞, to guess the average number y = α m ∑m µ= x µ – called the winning number – , where α ∈ [ , ] is fix and known to all players. we call a the set of alternatives. let us consider a representative player µ. for given choices x , . . . , xµ− , xµ+ , . . . , xm of players ν = µ, the optimal response of player µ is xµ = α m − α ∑ ν =µ xν = α m − m − α x(−µ), where x(−µ) = m− ∑ ν =µ x ν , such that xµ = y, i.e. with her best response player µ announces exactly the winning number y. note that for m large enough, m− m−α ≈ and thus x µ ≈ α x(−µ). naturally, player µ does not have any information about other players choices, since she must announce her number simultaneously to the others. therefore, she has to build beliefs about other players’ choices. let (Ω, f) be a measurable space. the random variable xν : Ω → a for ν = , . . . , m denotes players’ µ choice in a. the random variable x = m ∑m µ= x µ is the average over all announced numbers and y = α x is the winning number. moreover, x (−µ) = m− ∑ ν =µ x ν and y (−µ) = α x (−µ) . we introduce the following definition. definition (belief). the probability measure pµ on (Ω, f) is the belief of player µ = , . . . , m . f µ,ν denotes the cumulative distribution function of player ν’s choice xν under player µ’s belief pµ, for all ν, µ = , . . . , m . the probability measure pµ is an abstract way of characterizing players’ believes con- cerning the state of nature driving players choices. suppose for example the only two states of nature ω and ω exist, and that all other players choose the number if the state ω occurs and the number n if the state ω occurs. then each player’s believes is the probability associated to each state of nature. if one player believes the ω occurs with probability , then she would announce the number α n . it is to note that players could have different beliefs on the state of nature. nevertheless, to make the model tractable and to allow us to consider a representative player in the derivation of our results, we make the following simplifying assumptions. assumption . under pµ, x , . . . , xµ− , xµ+ , . . . , xm are independent and identically distributed for all µ = , . . . , m , i.e. other players’ choices are independent under each player’s belief and have the same distribution functions. moreover, xµ = α m − m − α x (−µ) . we assume that players use an iterative thinking process to guess the numbers which will be announced by other players. we add an index k to our previous notation to indicate that we are considering the thinking process at step k, i.e. xνk for ν = , . . . , m is the number that player ν would announce at step k of her thinking process, xk is the average over the xνk ’s and x (−µ) k is the average over the x ν k ’s for ν = µ. moreover, f µ k denotes the cumulative distribution function of xνk under p µ for µ, ν = , . . . , m , where assumption is supposed to hold also for x k , . . . , x µ− k , x µ+ k , . . . , xmk . let us consider player’s µ thinking process. step first, player µ assumes that all alternatives in a are equally probable for all other players, i.e. f µ corresponds to the uniform distribution on [ , n ]. under this assumption, the average number x (−µ) is the weighted sum of m − independent uniformly distributed random variables on [ , n ] and y⋆ := e µ [x µ ] = α m − m − α n , (σ⋆ ) := varµ(x µ ) = α ( m − m − α ) n . e µ [·] and varµ are the expectation and the variance respectively, under pµ. note that y⋆ and σ⋆ do not depend on µ. step in step , player µ takes into account the expected guessing number y⋆ she obtained from step . she considers an interval iµ around this number and assumes that the xνk ’s are independent distributed on i µ for all ν = µ. here, the reference probability measure is pµ. more precisely, player µ believes that for ν = µ and conditioning on unknown realizations l µ , u µ of independent random variables l µ ∼ unif([ , y⋆ ]) and u µ ∼ unif([ , n − y⋆ ]) respectively, the interval is iµ (l µ , u µ , ǫ) = [y ⋆ − ǫ l µ , y ⋆ + ǫ u µ ] ⊂ [ , n ], where ǫ ∈ [ , ] is fix and known to all players. later we will provide a simulation result, where it is assumed that ǫ is stochastically in [ , ], with known distribution function. moreover, here it is assumed that the xν ’s are conditionally independent and uniformly distributed on iµ (l µ , u µ , ǫ) given l µ , u µ . it follows that the conditional expectation of x µ given l µ , u µ is e µ [x µ |(l µ , u µ ) = (l µ , u µ )] = α m − m − α [ y⋆ + ǫ (u µ − l µ ) ] . the conditional variance is varµ [x µ |(l µ , u µ ) = (l µ , u µ )] = α ( m − m − α ) ǫ (u µ + l µ ) . since l µ and u µ are unknown, player µ will base her decision on the unconditional expec- tation y⋆ = e µ [x µ ] = α m − m − α [ y⋆ + ǫ ( n − y⋆ − y⋆ )] = α m − m − α [ y⋆ ( − ǫ ) + ǫ n ] . note that y⋆ does not depend on µ. the unconditional variance of x µ can be easily obtained using that for a random variable x and a σ-algebra b we have var [x] = e [var [x |b]] + var [e [x |b]] ( ) (feller ). let b = σ(lµ , u µ ), the σ-algebra generated by l µ and u µ , then it follows that (σ⋆ ) = varµ [x µ ] = α ( m − m − α ) ǫ [ n − n y⋆ + (y⋆ ) ] . proof. using that e µ [x µ |l µ , u µ ] = α m − m − α [ y⋆ + ǫ (u µ − l µ ) ] , varµ [x µ |l µ , u µ ] = α ( m − m − α ) ǫ (u µ + l µ ) and equation ( ) we have varµ [x µ ] = e µ [varµ [x µ |l µ , u µ ]] + var µ [eµ [x µ |l µ , u µ ]] = eµ [ α ( m − m − α ) ǫ (u µ + l µ ) ] +varµ [ α m − m − α [ y⋆ + ǫ (u µ − l µ ) ] ] = α ( m − m − α ) ǫ [ n − n y⋆ + (y⋆ ) ] . step k given y⋆k− from step k − , player µ believes that all players build intervals iµ k around y⋆k− and the x ν k ’s are independent distributed on i µ k . analogously to step , conditioning on unknown realizations l µ k , u µ k of independent random variables l µ k ∼ unif([ , y⋆k− ]) and u µ k ∼ unif([ , n − y⋆k− ]) respectively, the interval is given by iµ k (l µ k , u µ k , ǫ) = [y⋆k− − ǫ l µ k , y⋆k− + ǫ u µ k ] ⊂ [ , n ], figure : expected asymptotic winning number y∗ = y∗(n, β, ǫ) for m ∼ ∞ and n = . and the xνk ’s are conditionally uniformly distributed on i µ k (l µ k , u µ k , ǫ). the conditional expectation of x µ k given l µ k , u µ k is e µ [x µ k |(lµ k , u µ k ) = (l µ k , u µ k )] = α m − m − α [ y⋆k− + ǫ (u µ i − l µ i ) ] , and the conditional variance is varµ [x µ k |(lµ k , u µ k ) = (l µ k , u µ k )] = α ( m − m − α ) ǫ (u µ k + l µ k ) . following the same approach as by step , the unconditional expectation and variance are respectively y⋆k = e µ [x µ k ] = α m − m − α [ y⋆k− ( − ǫ ) + ǫ n ] , (σ⋆k) = varµ [x µ k ] = α ( m − m − α ) ǫ [ n − n y⋆k− + (y⋆k− ) ] . y⋆k and σ ⋆ k do not depend on µ. the sequence of expected winning numbers (y⋆k)i≥ converges to a limit y ⋆ as stated in the following proposition. figure gives the asymptotic expected winning number y⋆ as function of α and ǫ. proposition . let m > , a = [ , n ] and (y⋆k, k ≥ ) the sequence of expected guessing numbers defined above. then y⋆k = β k+ ( − ǫ )k n + β ǫ n − βk( − ǫ )k − β ( − ǫ ) . ( ) where β = α m− m−α . thus (y ⋆ k)i≥ is decreasing and y ⋆ k → y⋆ for k → ∞, where y⋆ = y⋆(n, m, α, ǫ) = { n ǫβ −β( −ǫ) for (α, ǫ) = ( , ), n for (α, ǫ) = ( , ) . ( ) consequently, the sequence (σ⋆k, k ≥ ) is increasing and σ⋆ = lim k→∞ σ⋆k = α m − m − α ǫ√ √ n − n y⋆ + (y⋆) . ( ) proof. from the computation above it follows that y⋆ = β n and y⋆k = β [ y⋆k− ( − ǫ ) + ǫ n ] . by applying iteratively the last equation we obtain y⋆k = β { β ( y⋆k− ( − ǫ ) + ǫ n ) ( − ǫ ) + ǫ n } = = β ( − ǫ ) y⋆k− + α ǫ n ( − ǫ ) + β ǫ n = = . . . = βk( − ǫ )k y⋆ + β ǫ n k− ∑ l= βl( − ǫ )l = = βk+ ( − ǫ )k n + β ǫ n − βk( − ǫ )k − β ( − ǫ ) . for k → ∞ and (β, ǫ) = ( , ) we obtain y⋆k → n ǫβ − β( − ǫ) . for (β, ǫ) = ( , ), it follows directly from the iteration that y⋆k = y ⋆ for all k ≥ . finally, note that β = if and only if α = . to prove that (σ⋆k, k ≥ ) is increasing, note that x → n − n x + x is decreasing on [ , n ]. thus, σ⋆k = α m− m−α ǫ√ √ n − n y⋆ k− + (y⋆ k− ) increases as y⋆k− decreases to y⋆. the continuity of f (x) implies that σ⋆k ր σ⋆. the proposition states that the thinking process generates a sequence of expected winning numbers that converges quickly to an asymptotic expected winning number y⋆, that depends on α, ǫ, n and the number of players m . the convergence is very fast, so that y⋆ well approximates the expected winning numbers obtained after only a few levels of thinking. this is shown in figure , which gives the numbers of thinking levels k that should be performed in order that y⋆k − y⋆ ≤ δ (note that by proposition , y⋆k ≥ y⋆), depending on the parameters β and ǫ. the curves in figure (a) correspond to fixed numbers of thinking levels k, such that the expected wining number after k levels of thinking y⋆k and the asymptotic winning number y ⋆ differ of at most of δ = . the figure (b) gives instead the number of thinking levels as function of ǫ for β = and δ = and . here convergence is within only - steps. the vertical lines correspond to the usual range for the parameter ǫ, as discussed in the introduction. from the proposition we also obtain that y⋆ is strictly positive, unless α = or ǫ = , i.e. the asymptotic expected winning number differs from the game-theoretic equilibrium if the confidence parameter is strictly positive. finally, the variance of the k-th level of thinking winning number yk is strictly increasing as k increases to ∞. this is due to the asymmetry of the intervals ik generated during the thinking process. the asymptotic winning number y⋆ can be also written as y⋆ = y⋆ ǫ − β ( − ǫ) , i.e. it corresponds to the initial guess y⋆ multiplied by a factor c(ǫ) < depending only on the confidence parameter ǫ (here β and m are given by the game setup). therefore, if players were informed about the initial expected winning number number y⋆ , then their thinking process would generated the asymptotic expected winning number y⋆ = y⋆ c(ǫ). this observation is the starting point of our discussion on the iterated guessing game of section . next, we derive the density probability function of the winning number at each level of thinking and asymptotically, i.e. for k → ∞. for sake of simplicity, let now con- sider a countable infinite group of players, i.e. m = ∞. then by the central limit theorem, under pµ and conditionally on the upper and lower bound l µ k , u µ k for the in- terval iµ k (l µ k , u µ k , ǫ), the random variable x µ k = α x (µ) k is normally distributed with mean m µ k = α ( y⋆k− + ǫ (u µ k − lµ k ) ) and variance (s µ k ) = α ǫ (u µ k + l µ k ) . the unconditional density function fk of x µ k under pµ is then given by fk(x) = y⋆ k (n − y⋆ k ) √ √ π ǫ α ∫ y⋆ k ∫ n−y⋆ k g(u, l; y⋆k− ) du dl, where g(u, l; y) = u+l exp ( − (√ (x−α y− ǫ α (u−l)) ǫ α (u+l) ) ) . (a) . . . . . . epsilon . . . . . . b e ta (b) . . . . . . epsilon n u m b e r th in ki n g le ve ls figure : (a) number of thinking levels such that y⋆k − y⋆ ≤ , depending on β and ǫ. the curves correspond to fixed numbers of thinking levels k. (b) number for thinking levels such that y⋆k − y⋆ ≤ δ as function of ǫ, for β = and δ = (full line) and δ = (dotted line). winning number y . . . . p ro b a b ili ty figure : asymptotic distribution of the winning number y , with α = , n = , ǫ = . (simulation with m = ). obviously, each player will announce her guessing number only once. in the limit k → ∞ we obtain the asymptotic unconditional density f under pµ f (x) = y∗(n − y∗) √ √ π ǫ α ∫ y∗ ∫ n−y∗ g(u, l; y⋆) du dl. ( ) the density function f is illustrated in figure . the distribution in the case of a heterogenous pop- ulation our results from section were obtained under the assumption that all players are ho- mogeneous, i.e. having the same confidence parameter ǫ and also performing the same number of levels of thinking (see proposition ). the advantage of these assumptions is that we were able to derive a closed form solution for the expected winning number at each level of thinking. the experimental results (see figures and ) do not support the assumption of an homogeneous population of players. for this reason, facing real data, we take an heterogenous ensemble, by making both parameters – the confidence param- eter and the number of thinking levels – random variables. following camerer, ho, and chong ( ) we will simulate the winning number y under the assumption that the number of thinking levels is poisson distributed with some intensity τ . figure shows figure : relative frequency of guessed numbers due to the model of “cognitive hierarchy” by camerer, ho, and chong ( ). the spectrum of guessed numbers is discrete. the results obtained by camerer, ho, and chong ( ), where no confidence parameter ǫ enters in the model (or equivalently, ǫ = ). the figure (b) shows instead our simulation result, where the number of thinking level of each player is the outcome of a poisson dis- tributed random variable with τ = , while the confidence parameter is randomly chosen in e = { −i : i = , . . . , ν} and ν = . for a comparison with our simulation, figure (a) reports the results from the german newspaper “die zeit” already shown in figure . we obtain a distribution of the winning number, that is now a superposition of a background distribution which is driven by the confidence parameter ǫ for the several level of thinking, and a series of peaks which correspond to the realizations of ǫ near to zero. convergence towards equilibrium we finally consider the case that the guessing game is played for a number of rounds. the rule is the same for any round and corresponds to the -shot game discussed previously, while between any two rounds the winning number determined in the preceding round is made public. within each round any player performs k levels of thinking. we can assume that all players perform the same number of iterations, since the convergence in each round is rapid, as shown in proposition . therefore, we assume that the winning number announced at the end of each period is the respective asymptotic winning number of this round, denoted by y⋆(t). while in round all players start with the initial guess y⋆( ) = β n the winning number announced at the end of round is y⋆( ) = c(ǫ ) y ⋆( ), where ǫ is the confidence parameter of the first round and c(·) is defined as in section . figure : distribution of the winning number y , under the assumptions that the number of thinking levels is poisson distributed with intensity τ = and the confidence parameter ǫ is uniformly distributed on e = { −i : i = , . . . , ν} with ν = . the other parameters are α = , n = and m = . estimates of ǫ in various iterated guessing games sessionα a b c d e f g h α / / / / / / / / ǫ . . . . . . . . r . . . . . . . . table : estimation of the confidence parameter ǫ for several experimental results. a , b , c , and d are nagel’s sessions − from nagel ( ) in which α = / , while e is from weber (http://www.andrew.cmu.edu/user/rweber/) and f is from the experi- ments at the university of bergen, while g , h are nagel’s sessions , for α = / taken also from nagel ( ). the number y⋆( ) is made public to all players at the beginning of round , so that all players start their new thinking process of round with y⋆( ) and they arrive at y⋆( ) = y⋆( ) c(ǫ ). note that since parameters β, n are given by the game rule, y ⋆(t) essentially only depends on the sequence (ǫ , . . . , ǫt) of confidence parameters up to time t. it might be expected that due to some adaptive mechanisms, ǫt might change over rounds. in fact, as a first order approximation we assume that the confidence parameter is constant over rounds, i.e. ǫt = ǫ + o(t) for all t. under these assumptions the iterative setting is governed by the following recurrence equation y⋆(t) ≈ y⋆(t − ) ǫ − β ( − ǫ) , ( ) where y∗( ) = β n . hence y⋆(t) ≈ y⋆( ) ( ǫ − β ( − ǫ) )t , or ln y⋆(t) ≈ ln y⋆( ) + t ln ( ǫ − β ( − ǫ) ) . therefore, since ǫ −β ( −ǫ) < , as t → ∞ the expected winning number y ∗(t) converges to . the following figure show real data from experimental studies. in figure three sessions are shown; data are from nagel ( ). the agreement with the prediction of our model with constant confidence parameter ǫ is surprising well. on the other hand it is not surprising that ǫ might be different in different experiments. table summarizes the numerical estimates. figure : data of the iterated guessing game due to nagel (sessions , , ) with α = / played with - subjects with ǫs ≈ , . , . (nagel ). conclusion ever since keynes, the α-beauty contest has served as a paradigmatic framework for strategic price formation processes on markets. it was shown experimentally that the - shot α-beauty contest is a non-equilibrium game under bounded rationality conditions, while equilibrium is established after a sufficient number of iterative rounds. unfortu- nately today non-equilibrium systems are only poorly understood, i.e. there does not exist a general theory of non-equilibrium systems describing their typical properties and their routes into equilibrium. hence without any general theory, one is left with studies of exemplary systems. in this note, we studied the α-beauty contest with arbitrary parameters and in dif- ferent settings, such as the -shot setting and the iterative setting with communication between rounds. our studies started from considerations of real data. experimental data of the -shot setting of the -equilibrium game exhibit a common pattern: the spectrum of announced numbers is a superposition of a skew background distribution and a regime of extra ordinarily often chosen numbers. our basic model proposed is able to explain this pattern. it reproduces as well as generalizes classical results. it is based on the assump- tion that players successively update their recent beliefs according to estimating intervals rather than numbers. note that our model has only one free parameter ǫ, which is the a measure for the confidence of the player in her guess. it was shown analytically that if players have only finite confidence in their recent belief, the expected winning number is strictly positive. the nash equilibrium is obtained if the players’ confidence in their guesses is infinite. the rate of convergence is shown to be high so that the expected asymptotic winning number is obtained after only very few thinking steps. this result of the model is consistent with the observation by nagel and others that about levels of thinking are sufficient to generate this expected winning number. if the players’ popula- tion is heterogenous with respect to the level of confidence, i.e. if the confidence parameter varies over the player’s population, numbers announced will have a highly skewed distri- bution in agreement with real data. hence our model explains the existence of a skew distribution of announced numbers observed in real data. the combination of camerer’s cognitive hierarchy theory with our model was shown to be able to reproduce the typical pattern observed in real data. a model of the α-beauty contest must also describe the route into equilibrium in the iterative setting as is observed in experiments. it is a straight forward consequence of the fast convergence over thinking steps, that convergence towards equilibrium should be polynomial in the number of rounds played. this prediction from our model is in good quantitative agreement with various experimental data. on a market, there is partial information exchange among traders. thus it would be interesting to consider the case of partial information among players between rounds. while our model makes clear predictions about the rate of convergence to maximum information gain and equilibrium, concrete data are needed for further investigation. references camerer, c. ( ): behavioral game theory: experiments on strategic interaction. princeton university press, princeton. camerer, c., t. ho, and j. chong ( ): “a cognitive hierarchy theory of one-shot games and experimental analysis,” working paper caltech, available from http://hss.caltech.edu/∼camerer/. costa-gomes, m., v. crawford, and b. broseta ( ): “cognition and bahavior in normal-form games: an experimental study,” econometrica, , – . de giorgi, e., and s. reimann ( ): “a remark on the guessing game,” working paper, institute for empirical research in economics, university of zurich. feller, w. ( ): an introduction to probability theory and its applications, vol. . wiley, new york. ho, t., c. camerer, and k. weigelt ( ): “iterated dominance and iterated best response in experimental “p-beauty contests”,” american economic review, , – . keynes, j. ( ): the general theory of interest, employment and money. macmillan, london. nagel, r. ( ): “unravelling in guessing game. an experimental study,” american economic review, , – . nagel, r., a. bosch-domènech, a. satorra, and j. garca-montalvo ( ): “one, two, (three), infinity: newspaper and lab beauty-contest experiments,” american economic review, , – . nagel, r., and j. duffy ( ): “on the robustness of behavior in experimental beauty-contest games,” economic journal, , – . plot, c. ( ): “rational behavior in markets and social choice processes,” social science working paper, caltech, no. . reimann, s. ( ): “towards understanding the guessing game: a dynamical sys- tems’ perspective,” physica a, forthcoming. stahl, d., and p. wilson ( ): “on players models of other players: theory and experimental evidence,” games and economic behavior, , – . working papers of the institute for empirical research in economics no. the working papers of the institute for empirical research in economics can be downloaded in pdf-format from http://www.iew.unizh.ch/wp institute for empirical research in economics, blümlisalpstr. , zurich, switzerland phone: fax: e-mail: bibiewzh@iew.unizh.ch ernst fehr, urs fischbacher and elena tougareva: do high stakes and competition undermine fairness? evidence from russia, july enrico de giorgi: reward-risk portfolio selection and stochastic dominance, august enrico de giorgi: a note on portfolio selections under various risk measures, august klaus reiner schenk-hoppé: resuscitating the cobweb cycle, july alois stutzer: the role of income aspirations in individual happiness, february ernst fehr and lorenz götte: do workers work more if wages are high? evidence from a randomized field experiment, july anke gerber, thorsten hens and bodo vogt: rational investor sentiment, december matthias benz and alois stutzer: do workers enjoy procedural utility?, september thorsten hens, klaus reiner schenk-hoppé and martin stalder: an application of evolutionary finance to firms listed in the swiss market index, august bruno s. frey, matthias benz and alois stutzer: introducing procedural utility: not only what, but also how matters, october ernst fehr and jean-robert tyran: limited rationality and strategic interaction, the impact of the strategic environment on nominal inertia, november armin falk, rafael lalive and josef zweimüller: the sucess of job applications: a new approach to program evaluation, november dirk engelmann and urs fischbacher: indirect reciprocity and strategic reputation, building in an experimental helping game, november u. fischbacher, christina m. fong and ernst fehr: fairness, errors and the power of competition, december e. fehr and john a. list: the hidden costs and returns of incentives – trust and trustworthiness among ceos, november bruno s. frey and matthias benz: being independent is a great thing: subjective evaluations of self- employment and hierarchy, may , revised version bruno s. frey and simon luechinger: terrorism: deterrence may backfire, december bruno s. frey and simon luechinger: how to fight terrorism: alternatives to deterrence, december thorsten hens and bodo vogt: money and reciprocity, november , revised version thorsten hens and klaus reiner schenk-hoppé: markets do not select for a liquidity preference as behavior towards risk, december ernst fehr and joseph henrich: is strong reciprocity a maladaptation? on the evolutionary foundations of human altruism, january ernst fehr, urs fischbacher, bernhard von rosenbladt, jürgen schupp and gert g. wagner: a nation-wide laboratory examining trust and trustworthiness by integrating behavioral experiments into representative surveys, january reto foellmi, manuel oechslin: who gains from non-collusive corruption?, january alois stutzer and bruno s. frey: does marriage make people happy, or do happy people get married?, january armin falk and andrea ichino: clean evidence on peer pressure, january reto foellmi, josef zweimueller: inequality, market power, and product diversity, march armin falk and michael kosfeld: it's all about connections: evidence on network formation, march bruno s. frey and alois stutzer: testing theories of happiness, april bruno s. frey and stephan meier: do business students make good citizens?, may bruno s. frey and stephan meier: the economics of museums, may armin falk, urs fischbacher and simon gächter: living in two neighborhoods – social interactions in the lab, may alois stutzer and bruno s. frey: stress that doesn’t pay: the commuting paradox, june michael kosfeld: network experiments, may aleksander berentsen, esther brügger and simon lörtscher: on cheating and whistle-blowing, december ucla ucla previously published works title bayesian phylogenetics with beauti and the beast . . permalink https://escholarship.org/uc/item/ ww j c journal molecular biology and evolution, ( ) issn - authors drummond, alexei j suchard, marc a xie, dong et al. publication date - - doi . /molbev/mss peer reviewed escholarship.org powered by the california digital library university of california https://escholarship.org/uc/item/ ww j c https://escholarship.org/uc/item/ ww j c#author https://escholarship.org http://www.cdlib.org/ bayesian hylogenetics with beauti and the beast . department of computer science, university of auckland, auckland, new zealand allan wilson centre for molecular ecology and evolution, university of auckland, auckland, new zealand departments of biomathematics and human genetics, david geffen school of medicine, university of california, los angeles department of biostatistics, school of public health, university of california, los angeles institute of evolutionary biology, university of edinburgh, edinburgh, united kingdom *corresponding author: associate editor: sudhir kumar abstract computational evolutionary biology, statistical phylogenetics, and coalescent-based population genetics are becoming in- creasingly central to the analysis and understanding of molecular sequence data. we present the bayesian evolutionary anal- ysis by sampling trees (beast) software package version . , which implements a family of markov chain monte carlo (mcmc) algorithms for bayesian phylogenetic inference, divergence time dating, coalescent analysis, phylogeography, and related molecular evolutionary analyses. this package includes an enhanced graphical user interface program called bayesian evolutionary analysis utility (beauti) that enables access to advanced models for molecular sequence and phenotypic trait evolution that were previously available to developers only. the package also provides new tools for visualizing and summa- rizing multispecies coalescent and phylogeographic analyses. beauti and beast . are open source under the gnu lesser general public license and available at http://beast-mcmc.googlecode.com and http://beast.bio.ed.ac.uk. key words: bayesian phylogenetics, evolution, phylogenetics, molecular evolution, coalescent theory. . r esearch article introduction molecular sequences, morphological measurements, geo- graphic distributions, and fossil remains all provide a wealth of potential information about the evolutionary history of life on earth, the dynamics of ancient and modern biologi- cal populations, and the emergence and spread of infectious diseases. one of the challenges of modern evolutionary bi- ology is the integration of these different data sources to ad- dress evolutionary hypotheses over the full range of spatial and temporal scales. the field is witnessing a transition to an increasingly quantitative science. this transformation be- gan first through an explosion of molecular sequence data with the parallel development of mathematical and compu- tational tools for their analysis. however, increasingly, this transformation can be observed in other aspects of evo- lutionary biology where large global databases of comple- mentary sources of information, such as fossils, geographical distributions, and population history, are being curated and made publicly available. software advances here, we present a major new version of the molecular evo- lutionary software package bayesian evolutionary analysis by sampling trees (beast), updated to version . , and representing a significant software advance over that previ- ously described (drummond and rambaut ). alongside the primary analysis engine in beast, this package also includes a suite of utilities for specifying the analysis design, processing output files, and summarizing and visualizing the results. taken together, these programs enable bayesian inference of molecular sequences with an emphasis on time-structured evolutionary models including phylody- namic models, divergence time estimates, multiloci demo- graphic models, gene–/species–tree inference, a range of spatial phylogeographic analyses, and discrete and contin- uous trait evolution. implementing markov chain monte carlo (mcmc) algorithms to perform these inferences, the package is intended and used for rigorous statistical infer- ence and hypothesis testing of evolutionary models with joint inference of phylogeny. it is also possible to constrain portions of the phylogenetic model space to known val- ues, including the tree topology, and perform conditional inference if required. user interface one area of significant improvement since the last release publication is in the analysis construction and model specification tool called bayesian evolutionary analysis utility (beauti). this acts as the graphical user interface (gui) for beast and allows the user to import data, select models, choose prior distributions on individual parameters, and specify the settings for the mcmc sampler (fig. ). although the beast model specification format (a standard xml format structured text file) allows for great flexibility in the construction of complex evolu- tionary models, the constraints of a gui unavoidably restrict the scope of the researcher to a prespecified set of models and combinations, hiding many advanced inference models. working directly within the beast xml input format, on the other hand, represents a high barrier to the accessibility of beast and incurs signif- icant risk of inadvertent errors being introduced into the model. we have concentrated development efforts on c© the author(s) . published by oxford university press on behalf of the society for molecular biology and evolution. this is an open access article distributed under the terms of the creative commons attribution non-commercial license (http://creativecommons.org/licenses/by-nc/ . ), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. open access e-mail: alexei@cs.auckland.ac.nz; msuchard@ucla.edu; a.rambaut@ed.ac.uk. alexei j. drummond,* , , marc a. suchard,* , , dong xie, , and andrew rambaut* , mol. biol. evol. ( ): – . doi: . /molbev/mss advance access publication february , p http://beast.bio.ed.ac.uk http://beast-mcmc.googlecode.com drummond et al. ∙ doi: . /molbev/mss mbe fig. . beauti gui for importing data and specifying the evolutionary model. beauti to provide greater flexibility in model specification while still maintaining the benefits of a visual, table-based representation of the model, and automatic generation of beast xml files. improvements to beauti provide support for multiple data partitions in a joint analysis and the input of fossil calibration and trait information. heterogeneous data multiple data partitions may reflect separate loci for simul- taneous inference of genealogies and species trees (heled and drummond ) and stochastic ancestral recombina- tion graph reconstruction (bloomquist and suchard ) or the growing wealth of nonsequence data and their re- spective substitution models. these latter data and models include microsatellite markers (wu and drummond ), phenotypic traits under a multistate stochastic dollo pro- cess (alekseyenko et al. ), discretized geographic dif- fusion (lemey et al. ), and multivariate continuous re- laxed random walks (lemey et al. ). we also ease the use of a growing number of tree prior specifications. these include the extended bayesian skyline model (heled and drummond ) for multilocus data, the flexible gaussian markov random field skyride model (minin et al. ), and birth–death models of speciation (stadler ). multispecies coalescent discordance between individual gene trees that share a phy- logenetic history results from incomplete lineage sorting and becomes increasingly likely when times between spe- ciation events are short compared with species’ popula- tion sizes. we provide a fully bayesian implementation of the multispecies coalescent that improves the accu- racy and precision of species tree reconstruction (heled and drummond ) and divergence time estimation (mccormack et al. ). phenotypic trait analysis for trait inference including phylogeography, we now provide several tools for mapping posterior distributions of trees onto higher dimensional or geographics maps for both interactive exploration and better visualization (bielejec et al. ). these tools interface with googleearth via keyhole markup language and enable users to gener- ate animations of evolutionary processes through time and real space; see http://www.phylogeography.org for several examples. molecular clocks we have refined the relaxed clock models to allow more than one branch to have the same rate value to remove an- ticorrelation. in practice, this will only have any apprecia- ble impact on trees that have a small number of branches (< taxa). an efficient implementation of the relaxed clock models that facilitates calculation of bayes factors for model selection and model averaging of several clock mod- els has also be developed (li and drummond, ). fur- ther, we provide a new random local clock (rlc) model http://www.phylogeography.org bayesian phylogenetics with beauti and the beast . ∙ doi: . /molbev/mss mbe fig. . simultaneous phylogenetic and phenotypic trait reconstruction of darwin’s finches. plotted are the maximum clade credibility tree and posterior estimate of the trait correlation matrix. we annotate the tree with estimates of selected posterior clade support values and the one significant nucleotide substitution local clock (in red) and the branches scale in expected substitutions per site. we depict correlation coefficients through their bivariate ellipse sizes, where more highly correlated phenotypes return narrower ellipses. (drummond and suchard ), in which all possible lo- cal clock configurations and a strict clock are nested, pro- viding a convenient model to test for a strict clock. heled and drummond ( ) begins to investigate alternative approaches to the calibration of tree priors with fossil and geological evidence, and this area of research is still in its infancy. often, uncertainty exists in the age of viral rna/dna or ancient dna samples and these can now be incorporated (shapiro et al. ), along with models for se- quence damage and error (rambaut et al. ). performance finally, to exploit high-performance computing, beast . integrates with and provides a gui interface to config- ure the beagle library (ayres et al. ) that utilizes multicore processors, vectorization, and massively parallel graphics processors to substantially decrease beast run- times (suchard and rambaut ). examples figure presents a reconstruction of the gene tree relating species of darwin’s finches from a , -bp partial nu- cleotide alignment of the mitochondrial control region and cytochrome b genes (sato et al. ) and five continuously measured phenotypic traits of the corresponding species (sulloway ). in performing this simultaneous inference, we exploit the rlc model (drummond and suchard ) and find evidence for one suggestive rate change (bayes fac- tor in favor of the rlc over a strict clock = . ) in the lineage leading to the cocos island finch, pinaroloxias inornata. multivariate brownian trait diffusion shows strong corre- lation between wing and tarsus length and between bill depth and gonys length. posterior trait prediction at any point along the history is possible and, currently unique to beast, comparative method inference is performed jointly with phylogenetic inference. our second example demonstrates the application of the multispecies coalescent model (*beast) to a , -bp fragment of the mitochondrial genome sequenced from darwin’s finches representing four species (geospiza fortis, g. magnirostris, camarhynchus parvulus, and certhidea oli- vacea). figure shows ) a representative gene tree and ) the two species trees with highest posterior probability. the % credible set for the species tree contains of the pos- sible tree topologies: . % (((f, m),p), o); . % ((f, m),(p, o)); and . % (((f, m),o), p). this uncertainty in the species tree arises despite overwhelming support for certhidea oli- vacea and camarhynchus parvulus as the nested outgroup species according to the gene tree (fig. a), due to the pos- sibility of incomplete lineage sorting in the deeper branches of the gene tree. the possibility of incomplete lineage sort- ing can be appreciated in figure c, in which a representa- tive gene tree is embedded inside the most probable species tree topology for this data, showing extensive incomplete lineage sorting in the geospiza clade and also depicting the reason that species trees necessarily have (sometimes much) younger divergence times than the corresponding gene tree might suggest. this example demonstrates that even for single-gene analyses, the multispecies coalescent can provide ) important insight into the potential for drummond et al. ∙ doi: . /molbev/mss mbe fig. . (a) representative gene tree of mitochondrial dna fragment from darwin’s finches of four species (geospiza fortis, g. mag- nirostris, camarhynchus parvulus, and certhidea olivacea). nodes that have posterior clade probabilities of greater than . are labeled with their posterior clade probability. (b) the two most probable species trees (solid line represents most probable species tree; dashed line is second most probable). (c) gene tree embedded in a point estimate of the species tree, including divergence times and effective population sizes. the x axis is divergence time in units of substitutions per site and the y axis is proportional to effective population size. incomplete lineage sorting, ) more accurate assessment of uncertainty in the species tree estimate, and ) better estimates of species divergence times. availability and future directions we make the beast package available in both executable and source code forms. beast requires java version . or greater and executables for windows, mac os, and linux platforms are located at http://beast.bio.ed.ac.uk, which serves as the main page for the package. this page also links to a sizable list of self-contained step-by-step tutorials cov- ering basic to advance usage of beast. popular tutorials describe how to use beast to infer population dynamics and phylogeographic processes and walk users all the way through to generating a range of graphical summaries of their results. googlecode houses the beast’s version-controlled source code at http://beast-mcmc.googlecode.com and links to two googlegroup discussion groups related to beast. the first is the “beast-users” group (http://groups. google.com/group/beast-users) with over , members. at the time of writing, developers belong to the “beast- dev” group that facilitates beast development across three continents. future development directions for beauti and beast fo- cus on easing the user experience in several ways. these in- clude in fitting hierarchical phylogenetics models (suchard et al. ) that commonly arise in studies of intrahost vi- ral evolution, in exploiting markovjump methods (minin and suchard ; o’brien et al. ) for computation- ally efficient and robust estimation of complex evolu- tionary processes under simple models, and in specifying phylogeographic models (lemey et al. , ) in a convenient geographical user interface. acknowledgments we thank the national evolutionary synthesis center for sponsoring a working group (software for bayesian evolu- tionary analysis) that facilitated the development of beast version . . we would also like to thank the many develop- ers and contributors to beast, including: alex alekseyenko, trevor bedford, erik bloomquist, joseph heled, sebastian hoehna, philippe lemey, sibon li, gerton lunter, sidney markowitz, vladimir minin, michael defoin platel, oliver py- bus, beth shapiro, and chieh-hsi wu. this work was sup- ported in part by funding from the marsden trust, national science foundation (dms ), national institute of health (r gm , r hg ), the royal soci- ety of london, biotechnology and biological sciences re- search council (bb/h / ), and the wellcome trust (wt ma). references alekseyenko a, lee c, suchard m. . wagner and dollo: a stochastic duet by composing two parsimonious solos. syst biol. ( ): – . ayres d, darling a, zwickl d, et al. ( co-authors). . bea- gle: an application programming interface and high-performance computing library for statistical phylogenetics. syst biol. ( ): – . bielejec f, rambaut a, suchard ma, lemey p. . spread: spatial phy- logenetic reconstruction of evolutionary dynamics. bioinformatics ( ): – . bloomquist e, suchard m. . unifying vertical and nonvertical evolution: a stochastic arg-based framework. syst biol. ( ): – . drummond aj, rambaut a. . beast: bayesian evolutionary analysis by sampling trees. bmc evol biol. : . drummond aj, suchard ma. . bayesian random local clocks, or one rate to rule them all. bmc biol. : . http://groups.google.com/group/beast-users http://groups.google.com/group/beast-users http://beast-mcmc.googlecode.com http://beast.bio.ed.ac.uk bayesian phylogenetics with beauti and the beast . ∙ doi: . /molbev/mss mbe heled j, drummond aj. . bayesian inference of population size history from multiple loci. bmc evol biol. : . heled j, drummond aj. . bayesian inference of species trees from multilocus data. mol biol evol. ( ): – . heled j, drummond aj. . calibrated tree priors for relaxed phylogenetics and divergence time estimation. syst biol. ( ): – . lemey p, rambaut a, drummond aj, suchard ma. . bayesian phy- logeography finds its roots. plos comput biol. ( ):e . lemey p, rambaut a, welch j, suchard m. . phylogeography takes a relaxed random walk in continuous space and time. mol biol evol. : – . li wls, drummond aj. . model averaging and bayes factor cal- culation of relaxed molecular clocks in bayesian phylogenetics. mol biol evol. : – . mccormack je, heled j, delaney ks, peterson at, knowles ll. . calibrating divergence times on species trees versus gene trees: implications for speciation history of aphelocoma jays. evolution : – . minin v, suchard m. . counting labeled transitions in continuous- time markov models of evolution. j math biol. : – . minin vn, bloomquist ew, suchard ma. . smooth skyride through a rough skyline: bayesian coalescent-based inference of population dynamics. mol biol evol. : – . o’brien j, minin v, suchard m. . learning to count: robust es- timates for labeled distances between molecular sequences. mol biol evol. : – . rambaut a, ho s, drummond aj, shapiro b. . accommodating the effect of ancient dna damage on inferences of demographic histories. mol biol evol. : – . sato a, o’huigin c, figueroa f, grant p, grant b, tichy h, klein j. . phylogeny of darwin’s finches as revealed by mtdna sequences. proc natl acad sci u s a. : – . shapiro b, ho s, drummond aj, suchard m, pybus o, rambaut a. . a bayesian phylogenetic method to estimate unknown sequence ages. mol biol evol. : – . stadler t. . sampling-through-time in birth–death trees. j theor biol. : – . suchard ma, rambaut a. . many-core algorithms for statistical phylogenetics. bioinformatics : – . suchard ma, kitchen cmr, sinsheimer js, weiss re. . hierarchi- cal phylogenetic models for analyzing multipartite sequence data. syst biol. : – . sulloway f. . the beagle collections of darwin’s finches (geospiz- inae). bull br mus. : – . wu c, drummond aj. . joint inference of microsatellite mu- tation models, population history and genealogies using trans- dimensional mcmc. genetics : – . music biology: all this useful beauty current biology vol no r in re-modelling of other parts of the nervous system, including the memory centres of the brain in the hippocampus [ ]. here, it interacts with stress hormones secreted from the adrenal gland (cortisol in man; corticosterone in mice), mediated by the nuclear hormone glucocorticoid receptor, gr [ ]. gr is known to be an important regulator of bdnf, and is thought to be the key link between early life stress effects on brain function and dendritic development, many of which can persist throughout life. we are only just starting to appreciate how nuclear hormone signaling systems couple to the circadian clockwork, and recent studies now point to a direct interaction between proteins encoded by so-called core clock genes (period, cryptochrome, reverb) and hormone signaling pathways [ ]. for instance, there is now evidence that rhythmic action of glucocorticoids may depend on oscillations of cryptochrome, which forms a physical partnership with the gr to repress its action at specific phases of the cycle [ ]. so, although the authors did not explore this, one important question is whether auditory responses, and long-term effects on nerve damage, might be mediated by stress hormones, which themselves are tightly clock-controlled. adrenal glucocorticoids will likely also be strongly activated by strong noise stimulation, but if they are key players, then the rhythmic interaction of the gr with the core clockwork of the cochlea may be involved. finally, there is an obvious and important practical implication for human health. noise levels at work are controlled by a complex legal framework, which defines tolerable levels, and requires the wearing of protective hearing devices. to what extent has such legislation accounted for possible circadian effects in man, and would it not now be important to assess whether shift-workers are especially vulnerable? in addition, many people voluntarily expose themselves to excessive noise in discos and night-clubs, and anecdotal evidence suggests that this appears to be an exclusively nocturnal activity in our species. it is now important to test whether we show similar phasic effects to mice — with increased vulnerability at night. one intriguing prediction is that we might be better able to cope with noise in the night-time, since in man the daily rhythm of adrenal stress hormones rises in the day, and falls at night — the opposite to that seen in nocturnal mice. references . bailes, h.j., and lucas, r.j. ( ). melanopsin and inner retinal photoreception. cell. mol. life sci. , – . . frankland, p.w., and ralph, m.r. ( ). circadian modulation in the rat acoustic startle circuit. behav. neurosci. , – . . meltser, i., cederroth, c.r., basinou, v., savelyev, s., lundkvist, g.s., and canlon, b. ( ). trkb-mediated protection against circadian sensitivity to noise trauma in the murine cochlea. curr. biol. , – . . yoo, s.h., yamazaki, s., lowrey, p.l., shimomura, k., ko, c.h., buhr, e.d., siepka, s.m., hong, h.k., oh, w.j., yoo, o.j., et al. ( ). period ::luciferase real-time reporting of circadian dynamics reveals persistent circadian oscillations in mouse peripheral tissues. proc. natl. acad. sci. usa , – . . yang, t., kersigo, j., jahan, i., pan, n., and fritzsch, b. ( ). the molecular basis of making spiral ganglion neurons and connecting them to hair cells of the organ of corti. hearing res. , – . . fariñas, i., jones, k.r., tessarollo, l., vigers, a.j., huang, e., kirstein, m., de caprona, d.c., coppola, v., backus, c., reichardt, l.f., et al. ( ). spatial shaping of cochlear innervation by temporally regulated neurotrophin expression. j. neurosci. , – . . patapoutian, a., and reichardt, l.f. ( ). trk receptors: mediators of neurotrophin action. curr. opin. neurobiol. , – . . hegarty, j.l., kay, a.r., and green, s.h. ( ). trophic support of cultured spiral ganglion neurons by depolarization exceeds and is additive with that by neurotrophins or camp and requires elevation of [ca +]i within a set range. j. neurosci. , – . . jang, s.w., liu, x., pradoldej, s., tosini, g., chang, q., iuvone, p.m., and ye, k. ( ). n-acetylserotonin activates trkb receptor in a circadian rhythm. proc. natl. acad. sci. usa , – . . gómez-palacio-schjetnan, a., and escobar, m.l. ( ). neurotrophins and synaptic plasticity. curr. top. behav. neurosci. , – . . numakawa, t., adachi, n., richards, m., chiba, s., and kunugi, h. ( ). brain-derived neurotrophic factor and glucocorticoids: reciprocal influence on the central nervous system. neuroscience , – . . han, d.h., lee, y.j., kim, k., kim, c.j., and cho, s. ( ). modulation of glucocorticoid receptor induction properties by core circadian clock proteins. mol. cell endocrinol. , – . . lamia, k.a., papp, s.j., yu, r.t., barish, g.d., uhlenhaut, n.h., jonker, j.w., downes, m., and evans, r.m. ( ). cryptochromes mediate rhythmic repression of the glucocorticoid receptor. nature , – . faculty of life sciences, university of manchester, manchester m pt, uk. e-mail: andrew.loudon@manchester.ac.uk http://dx.doi.org/ . /j.cub. . . music biology: all this useful beauty some healthy people fail to derive pleasure from music despite otherwise preserved perceptual and reward responses. such ‘musical anhedonia’ implies the existence of music-specific brain reward mechanisms, which could provide a substrate for music to acquire biological value. camilla n. clark, laura e. downey, and jason d. warren few problems in biology are as tantalising as the problem of music. music is universal in human societies, apparently ancient and apt to generate powerful emotional responses [ ]. these are all properties that a biologically salient stimulus ought to have; however, these abstract sounds serve no obvious biological purpose and, unlike language, have no straightforward messaging function. this apparent paradox has long polarised neurobiologists and philosophers alike: in one account, music had a specific role in human evolution, probably linked to emotional social signalling [ ]; in the other, it is a mere neural confection, a spandrel of language [ ]. one important line of evidence in support of a biological role for music is the existence of specific neural mechanisms that process it: if evolution fashioned music-specific brain systems, it is reasonable to conclude that music (or proto-music) filled some evolutionary role for our species and to ask what that role might have been. evidence for such music-specific brain systems has mainly been adduced in patients with focal brain damage who show dissociated patterns of performance when processing music versus other kinds of complex sounds [ ]. such cases, while informative, mailto:andrew.loudon@manchester.ac.uk http://dx.doi.org/ . /j.cub. . . http://crossmark.crossref.org/dialog/?doi= . /j.cub. . . &domain=pdf dispatch r pose substantial challenges of interpretation. a new study reported in this issue of current biology by mas-herrero et al. [ ] sheds fresh light on this issue, by demonstrating that some healthy people derive little pleasure from music and lack autonomic responses to it, even though they perceive music normally and show preserved responses to other rewarding stimuli. such selective ‘musical anhedonia’ might, by demonstrating music-specific brain reward systems, suggest how and why music acquired reward potential for the wider human population. music engages ancient brain reward systems the new findings of mas-herrero et al. [ ] build on a growing body of work delineating the neurobiological basis of musical reward. a sensory stimulus is, in general, ‘rewarding’ if it engenders a pleasure response that encourages behavioural repetition [ ]. music fits this bill very well: intensely pleasurable responses to music (shivers down the spine or ‘chills’) are specifically and reliably triggered by particular musical features — such as the resolution of tonal ambiguity [ ] — and listeners typically seek to repeat the experience. musical shiver has been shown to activate a distributed brain network including phylogenetically ancient limbic, striatal and midbrain structures that are also engaged by cocaine and sex [ ]. the mesolimbic striatal dopaminergic system encodes musical reward by modulating the connectivity of nucleus accumbens with auditory cortical and other brain regions involved in the perceptual analysis and evaluation of music [ ]. mas-herrero et al. [ ] show that individuals with typical hedonic behavioural and autonomic (skin conductance) responses to music have comparably intense responses to other primary (biological) and secondary reinforcers of reward, notably money. this is not to argue, of course, that all these reinforcers are somehow biologically equivalent: the neurochemical response to music is complex and includes elements such as oxytocin release that are more closely aligned with social functions such as pair bonding than arousal per se [ ]. nevertheless, the high stake music holds in the hedonic and biological value system of many members of our species is, at the least, surprising. core components of music processing show individual variation mas-herrero et al. [ ] contribute two crucial new pieces to the puzzle of musical reward. firstly, they show that the reward potential of music varies widely between healthy people, and that this range includes individuals who are apparently cognitively and physiologically largely indifferent to music. secondly, they show that such anhedonia can be selective for music. didn’t we already suspect that some people just don’t ‘get’ music? now we have a rigorous neurobiological grounding for this suspicion. musical anhedonia is shown by this new study [ ] to be specific for musical reward assignment, rather than attributable to any deficiency in perceiving or recognising music or musical emotions. it is rooted in reduced autonomic reactivity rather than simply cognitive mislabelling. moreover, it is not attributable to more general hedonic blunting, because musically anhedonic individuals show typical responses to other sources of biological and non-biological (monetary) reward. there may be an informative analogy here with congenital amusia (‘tone deafness’), which affects specific components of music perception while apparently leaving other perceptual and cognitive domains largely unscathed [ , ]. a further interesting analogy might be drawn with clinical cases of selective musical anhedonia resulting from strategic focal brain damage [ ]. musical anhedonia and tone deafness might herald a new taxonomy of specific developmental disorders of music processing to complement the large evidence base for acquired amusias [ ]. specific brain circuits may signal the biological value of music the most parsimonious interpretation of the new findings is that there are music-specific brain reward systems to which individuals show different levels of access. mas-herrero et al. [ ] propose that this specificity may be instantiated in integrated profiles of connectivity across brain networks that link perceptual, evaluative and reward processing mechanisms: this suggestion sits well with previous neuroimaging work both in the healthy brain [ , ] and in selective brain network degenerations involving the coding of music versus other categories of salient stimuli [ , ]. natural selection is itself parsimonious and the existence of specific brain substrates for music coding in turn implies that these evolved in response to some biological imperative. but what might that have been? clues may lie in the cognitive and neuroanatomical architecture of music processing. it has been suggested that music may appeal to the inherent fondness of our species for puzzle solving, including the resolution of perceptual ambiguity intrinsic to musical scenes [ ] and pattern prediction and completion [ ]. certainly the extensive linkages between the neural machinery of emotion, reward and auditory cortical mechanisms engaged during music processing would provide an ample neuroanatomical substrate for musical pattern analysis to acquire biological resonance. how would such an abstract activity confer a reproductive or survival advantage, of the sort required for natural selection to operate? the answer may lie in the kinds of puzzles that music helped our hominid ancestors to solve (figure ). arguably the most complex, ambiguous and puzzling patterns we are routinely required to analyse are the mental states and motivations of other people, with clear implications for individual success in the social milieu. music can model emotional mental states and failure to deduce such musical mental states correlates with catastrophic inter-personal disintegration in the paradigmatic acquired disorder of the human social brain, frontotemporal dementia [ ]. furthermore, this music cognition deficit implicates cortical areas engaged in processing both musical reward and ‘theory of mind’ (our ability to infer the mental states of other people) [ , , ]. our hominid ancestors may have coded surrogate mental states in the socially relevant form of vocal sound patterns [ ]. by allowing social routines to be abstracted, rehearsed and potentially modified without the substantial cost of enacting the corresponding scenarios, such coding may have provided an bg am stg hi ofc atl vmpf ac ins na current biology dopaminergic modulation of circuit connectivity: prediction testing pattern completion, resolution: modelling affective mental states autonomic, affective, evaluative responses: emotion and reward music perceptual coding: patterns and expectations figure . a neural architecture for encoding the biological value of music. the schematic dissected brain (upper panel) shows anatomical networks implicated in music perceptual coding (red), emotion and reward processing (green) and higher-order cognitive processing (blue). key: ac, anterior cingulate cortex; am, amygdala; atl, anterior temporal lobe; bg, basal ganglia; hi, hippocampus; ins, insula; na, nucleus accumbens (mesolimbic stria- tum); ofc, orbitofrontal cortex; stg, superior temporal gyrus (and connected areas surrounding sylvian fissure); vmpf, ventro-medial prefrontal cortex. a proposed functional architecture for information exchange between these networks — based on empirical data [ , , – , – ] — is outlined (lower panel; arrows code putative primary direction of information flow). current biology vol no r evolutionary mechanism by which specific brain linkages [ ] assigned biological reward value to precursors of music. future directions these new insights into musical anhedonia raise many intriguing further questions. what is its neuroanatomical basis? the strong prediction would lie with mesolimbic dopaminergic circuitry, but functional neuroimaging support is sorely needed. what are the limits of the phenomenon? might typically musically hedonic individuals show ‘musical satiety’ with frequent exposure to their favourite music? the extent to which music shares a dynamic hedonic signature with, say, chocolate could illuminate the neurobiology of reward reinforcers more generally. what of the other end of the spectrum, individuals with ‘musicophilia’ who are hyper-hedonic for music? how does this relate to abnormal selective craving for music in some patients with temporal lobe seizures and specific neurodegenerative pathologies [ ]? such cases seem to mirror the phenomenon of musical anhedonia. more fundamentally, what are the wider implications for our understanding of other anhedonias? we have all met people who seem unmoved by food, sex or indeed, money. is this a matter of volition, cognition or reward biology? the current status of music as a dispensable cultural artefact (like culturally sanctioned examples of prolonged voluntary fasting or celibacy) is not necessarily a reliable guide to its neurobiological history. the work of mas-herrero et al. [ ] argues that the human brain is biologically fitted to find music rewarding. the beauty we find in music, however useless it may appear, has proved useful for probing the organisation of brain reward systems. now we must ask if music sculpted our hedonic brain architectures to more fundamentally useful neurobiological ends. references . zatorre, r.j., and salimpoor, v.n. ( ). from perception to pleasure: music and its neural substrates. proc. natl. acad. sci. usa (suppl ), – . . mithen, s. ( ). the music instinct: the evolutionary basis of musicality. ann. ny acad. sci. , – . . pinker, s. ( ). how the mind works (new york: norton). . stewart, l., von kriegstein, k., warren, j.d., and griffiths, t.d. ( ). music and the brain: disorders of musical listening. brain , – . . mas-herrero, e., zatorre, r.j., rodriguez- fornells, a., and marco-pallares, j. ( ). dissociation between musical and monetary reward responses in specific musical anhedonia. curr. biol. , – . . huron, d. ( ). sweet anticipation: music and the psychology of expectation (cambridge: mit press). . blood, a.j., and zatorre, r.j. ( ). intensely pleasurable responses to music correlate with activity in brain regions implicated in reward and emotion. proc. natl. acad. sci. usa , – . . salimpoor, v.n., van den bosch, i., kovacevic, n., mcintosh, a.r., dagher, a., and zatorre, r.j. ( ). interactions between the nucleus accumbens and auditory cortices predict music reward value. science , – . . chanda, m.l., and levitin, d.j. ( ). the neurochemistry of music. trends cogn. sci. , – . . phillips-silver, j., toiviainen, p., gosselin, n., and peretz, i. ( ). amusic does not mean unmusical: beat perception and synchronization ability despite pitch deafness. cogn. neuropsychol. , – . . tillmann, b., gosselin, n., bigand, e., and peretz, i. ( ). priming paradigm reveals harmonic structure processing in congenital amusia. cortex , – . . griffiths, t.d., warren, j.d., dean, j.l., and howard, d. ( ). ‘‘when the feeling’s gone’’: a selective loss of musical emotion. j. neurol. neurosurg. psychiatry , – . . sescousse, g., caldu, x., segura, b., and dreher, j.c. ( ). processing of primary and secondary rewards: a quantitative meta-analysis and review of human functional neuroimaging studies. neurosci. biobehav. rev. , – . . omar, r., henley, s.m., bartlett, j.w., hailstone, j.c., gordon, e., sauter, d.a., frost, c., scott, s.k., and warren, j.d. ( ). the structural neuroanatomy of music emotion recognition: evidence from frontotemporal lobar degeneration. neuroimage , – . . hsieh, s., hornberger, m., piguet, o., and hodges, j.r. ( ). brain correlates of musical and facial emotion recognition:evidence from the dementias. neuropsychologia , – . dispatch r . pressnitzer, d., suied, c., and shamma, s.a. ( ). auditory scene analysis: the sweet music of ambiguity. front. hum. neurosci. , . . downey, l.e., blezat, a., nicholas, j., omar, r., golden, h.l., mahoney, c.j., crutch, s.j., and warren, j.d. ( ). mentalising music in frontotemporal dementia. cortex , – . . fletcher, p.d., downey, l.e., witoonpanich, p., and warren, j.d. ( ). the brain basis of musicophilia: evidence from frontotemporal lobar degeneration. front. psychol. , . dementia research centre, ucl institute of neurology, university college london, – queen square, london, wc n bg, uk. e-mail: camilla.clark@ucl.ac.uk (c.n.c.), l.downey@ucl.ac.uk (l.e.d.), jason.warren@ ucl.ac.uk (j.d.w.) http://dx.doi.org/ . /j.cub. . . plant development: from biochemistry to biophysics and back since plant cells cannot move relative to each other, plant organogenesis mainly depends on the strict coordination of cell growth and proliferation. recent work suggests that this implies a subtle combination of biochemical and physical interactions between neighboring cells. jan traas* and massimiliano sassi plants continuously produce new organs and tissues, which is an essential adaptation to their sessile nature. this constant growth originates from two specific types of stem cells — the shoot and root apical meristems — that are active throughout plants’ life cycle. plant cells are encased in a rigid extracellular, polysaccharidic matrix, the cell wall, which links them together and prevents any form of cell migration or sliding. for this reason, the generation of new organs in plants is a complex process that requires the coordinated regulation of cell growth and proliferation, as otherwise the differences in growth rate would tear the tissue apart. vermeer and coworkers [ ], in a study recently published in science, have studied this coordination during lateral root formation, demonstrating how the coordinated behavior of two adjacent cell layers, located deep within the root, underlies the initiation of lateral root primordia (lrp). lateral roots are initiated in the pericycle, an inner cell layer adjacent to the vascular bundle at the center of the root, after an initial specification of the founder cells by the hormone auxin. following this priming step, these founder cells undergo a series of asymmetric cell divisions giving rise to the meristem of the lrp [ ]. the pericycle is overlaid by three other cell layers (endodermis, cortex and epidermis, from the innermost to the outermost, respectively) putting a strong mechanical constraint on the proliferation of pericycle founder cells, and thus the emergence of the lrp [ ]. it was previously shown that lrp outgrowth requires the production of cell wall remodeling enzymes in the cortex and epidermis to disrupt the adhesion between adjacent cells [ ]. the endodermis is far more rigid than the outer layers due to the presence of the casparian strip, a hydrophobic, lignified structure that functions as a solute barrier isolating the vasculature from the outer environment and keeps the endodermal cells tightly connected. vermeer and coworkers [ ] show how this hurdle is taken by the lrp. as soon as the proliferation of the lrp founder cells in the pericycle begins, the overlying endodermal cells start to shrink due to the fragmentation of their vacuoles, while the fusion of the inner and outer plasma membranes creates a gap in the tissue that allows the protrusion of the primordium. the casparian strip is only partially degraded around the gap, leaving the connections between endodermal cells largely unaltered. these events are regulated by auxin through the cell-autonomous action of the shy transcriptional regulator in the endodermis [ ]. importantly, if the endodermis accommodation mechanism is impaired, as when a dominant negative version of the shy protein is expressed in the endodermis, root founder cells fail to proliferate, despite the pre-existing auxin- mediated priming. the authors suggest that, in this case, the mechanical stress caused by an unaccommodating endodermis prevails, halting the genetic programme imposed by auxin. the work thus reveals what seems to be part of an interplay between biophysical and biochemical regulation, central in the formation of the lrp. this goes back to even earlier stages of lateral root specification. previous work showed that a transient bending of the primary root, either manually imposed or caused by gravitropism, induces the formation of a lrp at the convex side of the bending [ – ]. root bending has been proposed to somehow alter auxin concentrations in the pericycle and the adjacent vasculature by locally modifying auxin transport [ , ]. this might be due to mechanically induced changes in cell polarity, cell shape or ca + fluxes [ – ]. this mechanical regulation would, however, not be the starting point. indeed, further upstream massive orchestrated fluctuations in gene transcription at the root tip seem to confer competence of the cells to react to the physical constraints imposed by bending [ ]. from primary gene oscillations to the final breakthrough of the lateral root via mechanical priming, hormonal specification and the biochemical loosening of physical constraints, there seems to be a constant ‘back-and- forth’ between biochemical and biophysical regulation in the process of lateral root initiation. this interplay between biochemical and biophysical regulation is not limited to the root. in the aerial part of the plant, the shoot apical meristem constantly generates new leaves, flowers and floral organs. similarly to lrp development, the spatio-temporal priming of the organ primordia at the shoot apex is controlled by auxin [ ]. differently from roots, however, it is mailto:camilla.clark@ucl.ac.uk mailto:jason.warren@ucl.ac.uk mailto:jason.warren@ucl.ac.uk http://dx.doi.org/ . /j.cub. . . http://crossmark.crossref.org/dialog/?doi= . /j.cub. . . &domain=pdf music biology: all this useful beauty music engages ancient brain reward systems core components of music processing show individual variation specific brain circuits may signal the biological value of music future directions references can beauty be ignored? effects of facial attractiveness on covert attention © the psychonomic society, inc. there is now substantial evidence that faces capture at- tention more than do most common objects (e.g., ro, rus- sell, & lavie, ). moreover, certain facial information, such as expressions of anger and fear, evokes attention more easily than do neutral faces. attention to such information is often rapid, unconscious, and mandatory (see palermo & rhodes, , for a review). in the present study, we exam- ine whether the same characteristics are found in attention for facial beauty. this should offer important insights about how attentional systems prioritize and select meaningful biological information. the impact of beauty on social be- havior has been well documented in the literature (langlois et al., ). however, unlike attention to emotions, atten- tion to facial attractiveness has been studied little. olson and marshuetz ( ) have shown that facial beauty is appraised even when face images are presented for less than msec and followed by backward mask- ing. their study suggests that facial attractiveness can be detected rapidly from transient and degraded visual infor- mation. other studies have shown that participants tend to look longer at attractive than at unattractive faces (aharon et al., ) or take longer to decide on the attractiveness of attractive than on that of unattractive faces (kranz & ishai, ). recent literature also has suggested that neu- ral responses to facial beauty are engaged automatically, because they can be measured even when participants are performing a task unrelated to the explicit task of judg- ing facial attractiveness (aharon et al., ; o’doherty et al., ; winston, o’doherty, kilner, perrett, & dolan, ). however, because attention in these studies was focused directly on the location where face images were presented, it is not clear whether appraisal for attractive- ness can be achieved if spatial attention has already been directed elsewhere. is the appraisal for beauty mandatory in such a way that attractive faces can compete automati- cally with an ongoing task for attentional resources? also, because faces were presented at fixation in these studies, it is not clear whether facial attractiveness can be detected outside the foveal vision. to f ind answers to these questions, we employed a spatial endogenous cuing task in which participants were asked to determine whether a laterally presented target letter was upright or inverted and to ignore a face (which they were told was task irrelevant) flashed briefly on the opposite side of the display. the likely position of the forthcoming target was indicated by a central cue, which was used to induce covert attention (i.e., visual attention without orienting eye movements) to the cued location. we examined the presence of attractive faces on the task performance. we hypothesized that, relative to the pres- ence of an unattractive face, the presence of an attractive face would create a stronger interference with the task be- cause attractive faces may automatically pull the attention away from the target. to assess the effect of facial attractiveness on covert orienting, the face image and the target in each trial were presented simultaneously. because the duration of a single eye fixation usually exceeds msec (rayner, ), the target and the face in this study were shown for no longer than msec, to suppress saccadic orienting to can beauty be ignored? effects of facial attractiveness on covert attention jie sui university of hull, hull, england and northeast normal university, changchun, jilin, china and chang hong liu university of hull, hull, england facial beauty has important social and biological implications. research has shown that people tend to look longer at attractive than at unattractive faces. however, little is known about whether an attractive face presented outside foveal vision can capture attention. the effect of facial attractiveness on covert attention was investigated in a spatial cuing task. participants were asked to judge the orientation of a cued target presented to the left or right visual field while ignoring a task-irrelevant face image flashed in the opposite field. the presentation of attractive faces significantly lengthened task performance. the results suggest that facial beauty automatically competes with an ongoing cognitive task for spatial attention. psychonomic bulletin & review , ( ), - doi: . /pbr. . . j. sui, jie.sui@hull.ac.uk can beauty be ignored? facial attractiveness on attentional orienting is maximal. in the ex- perimental conditions, an attractive or unattractive face was shown simultaneously with the target for msec (experiments and ) or msec (experiment ). experiments and were identical, except for the different target and face durations. in the baseline condition, the target and peripheral box were shown without a face for the same duration. we used this condition to evaluate the dif- ference between the results of face-present and face-absent trials. the next frame showed the fixation point and peripheral boxes for a time ranging from to , msec, to prevent easy predictions about the onset of the next trial. participants were expected to re- spond within this time frame, and the next trial started regardless of whether a response was recorded. participants were told to ignore the faces while judging whether the target letter “t,” presented on the opposite side, was upright or inverted. they were instructed to respond as quickly and accurately as possible by pressing one of the two specified keys on the keyboard. participants were also reminded to maintain central fixation throughout the trials. in experiments and , a total of practice trials were run before the experimental trials. each of the conditions ( irrelevant stimuli visual fields soas) in the experimental trials had valid and invalid trials. participants were given short breaks after every trials. experiment was identical to experiment , except that the long soa ( -msec) condition was excluded. this change was made because neither experiment nor experiment showed any effect of facial attractiveness at this soa. because the interval between the cue and target onset was msec or longer in this study, the results in these experiments could be af- fected by stimulus-driven eye movements, even though the partici- pants were told to maintain fixation. to test this possibility, in experi- ment we examined potential contributions of eye movements by recording electrooculograms (eogs) of participants (see hawkins et al., , for more details about this method). the eogs were re- the stimuli. to make the task more difficult, the presenta- tion time for these was reduced further from msec in experiment to msec in experiment . if attractive faces capture spatial attention automatically, the effects should be relatively independent of task difficulty. finally, we conducted experiment to replicate our main findings and to determine the role of eye movements. method participants a total of undergraduate and graduate students from the university of hull participated in this study. experiment had participants ( females, males; ages – years; mean age . years). experiment had participants ( females, males; ages – years, mean age . years). experiment had participants ( females, males; ages – years; mean age . years). all participants had normal or corrected-to- normal vision. stimuli the face database was obtained from the university of st. an- drews. it contains frontal-view caucasian faces whose external features (hair and clothing) were removed. all faces in the database were prerated by raters (ages – years; females) for at- tractiveness on a -point scale. to contrast the effect of attractive- ness, only the most attractive and least attractive faces were used. the mean ratings for the two groups of faces were . and . , respectively. these were significantly different from each other ( p . ). both the attractive and the unattractive face groups con- tained equal numbers of males and females. four of these faces were reserved as the practice stimuli. the face size was normalized to pixels from ear to ear, which subtended . º of visual angle. because face identification is highly sensitive to image contrast in peripheral presentation (mäkelä, näsänen, rovamo, & melmoth, ; melmoth, kukkonen, mäkelä, & rovamo, ), the lumi- nance and contrast of the images were scaled to their means, so that these low-level image properties could contribute little to any be- havioral difference. the cuing displays consisted of a central fixation point, a cue, and two . º . º white boxes on a neutral gray background (see figure ). the distance between the center of the display and the outer edge of each box measured . º of visual angle. the cue was a . º white arrow. the target display consisted of a target letter “t” embedded in the center of an array of eight distractor crosses (see figure ). this configuration was the same from trial to trial. the size of the target and distractors was . º . º. the letter “t” was shown either upright or inverted. e-prime . was used to control the flow of the experiment and to collect response data. procedure participants were tested individually. an adjustable headrest was used to fix the participant’s viewing position, which was set cm away from the computer monitor. the procedure for each trial of the experiments is illustrated in figure . each trial began with a central fixation cross and two peripheral boxes. the fixation cross was shown for msec. it was then replaced by a -msec cen- tral cue, which pointed randomly to the right or left box. in % of trials (valid trials), the cue indicated the target location. in the remaining % (invalid trials), the cue pointed to the wrong loca- tion. the interstimulus interval before the target presentation was or msec. the stimulus onset asynchrony (soa), or the interval between the onset of the cue and that of the target, was thus or msec. as has been reported in the literature, soas around this range consistently produce a relatively strong attention-orienting effect, in which valid cues create faster responses to a target than do invalid cues (funes, lupiáñez, & milliken, ). we used the two soas to determine the temporal window within which the effect of or fixation ( msec) cue ( msec) isi ( or msec) target ( msec) fixation ( – , msec) valid invalid figure . illustration of the procedure used in the study. the target duration in experiment was changed from to msec. sui and liu the right visual field. there was also a main effect of ir- relevant stimuli [f( , ) . , p . ], in instances where rt was significantly longer for attractive and unat- tractive faces than in the baseline condition ( ps . ). however, since there were no significant interactions in- volving visual field and irrelevant stimuli (all ps . ), the data from the two visual fields were combined in the subsequent analyses. this showed a significant three-way interaction of irrelevant stimuli cue validity soa [f( , ) . , p . ]. to identify the source of this interaction, we conducted two separate simple main effects analyses for the two soa conditions, which revealed that the effect of irrelevant stimuli occurred only at the shorter soa ( msec). as expected, valid cues produced faster rts than did invalid cues [f( , ) . , p . ]. we also found a sig- nificant interaction between irrelevant stimuli and cue validity [f( , ) . , p . ]. separate anovas were conducted for the invalid and valid cue conditions. a significant main effect of irrelevant stimuli was found in the valid cue condition [f( , ) . , p . ]. con- sistent with our hypothesis, attractive faces delayed rts more than did unattractive faces or the baseline condition [ts( ) . and . , ps . and . , respectively]. no difference was found between rts in the unattractive and baseline conditions [t( ) . , p . ]. the effect implies that facial beauty can trigger processes that corded with two pairs of electrodes, with a passband of . – hz, and were digitized at a sampling rate of hz. the horizontal eog was recorded from electrodes placed about . cm lateral to the left and right external canthi, and the vertical eog was recorded with electrodes located above and under the left eye. eye movement on a given trial was defined by deflections exceeding v. results the data were analyzed using repeated measures anovas. the four variables were irrelevant stimuli (at- tractive, unattractive, baseline), cue validity (valid vs. invalid), visual field (right vs. left), and soa ( vs. msec). the overall accuracy results in all experiments were high ( %– %). because no significant difference was found between the accuracy results for attractive and unattractive faces, we focus here mainly on the reaction time (rt) data. analyses of rt were based on the data for the correct responses only. rt outliers were defined as sds outside of the mean. we did not detect any outlier, using this criterion. experiment rt results from experiment are shown in figure . initial analysis showed a significant main effect of visual field [f( , ) . , p . ], where responses were faster when the target was presented in the left than in r t ( m se c) a attractive unattractive baseline valid invalid * * * * r t ( m se c) b valid invalid figure . mean reaction time (rt) in experiment as a function of irrelevant stim- uli, stimulus onset asynchrony (soa), and cue validity. error bars represent standard errors. (a) soa msec. (b) soa msec. can beauty be ignored? are shown in figure a. for comparison, results from pre- sentations in the right visual field are shown in figure b. only short soa results from this experiment are presented, because our subsequent analysis did not show effects of facial attractiveness in the long soa condition. all interactions involving irrelevant stimuli for the right visual field (irrelevant stimuli cue validity, irrelevant stimuli soa, and irrelevant stimuli cue validity soa) were also not significant ( ps . ). the results for visual field in this experiment were thus different from those in experiment , where the effect of facial attrac- tiveness was present in both visual fields. our main sta- tistical analysis was therefore conducted on the condition in which the face stimuli were presented in the left visual field. results from this condition revealed a significant three-way interaction of irrelevant stimuli cue valid- ity soa [f( , ) . , p . ]. separate anovas were conducted for the two soa conditions. as in experi- ment , the results for the long soa showed no significant main effect of irrelevant stimuli or interaction between this and cue validity ( ps . ), and only the short soa pro- duced a significant interaction between irrelevant stimuli and cue validity [f( , ) . , p . ]. also as in experiment , the rt was significantly slower when an at- tractive face was shown with the target than when an unat- tractive face [t( ) . , p . ] or baseline [t( ) compete with an ongoing cognitive task for attentional resources. in the invalid cue condition, on the other hand, rts for attractive and unattractive faces were comparable [t( ) . , p . ], although both were slower than rts in the baseline condition [ts( ) . and . , ps . and . , respectively]. experiment experiment showed that attractive faces affect spa- tial attention more strongly than unattractive faces did in the valid cue condition. experiment further investigated whether the effect could be replicated when the dura- tion of target and face stimuli was reduced from to msec. analysis of the rt data showed that the main effect of soa was significant [f( , ) . , p . ]: responses were faster for the long soa than for the short soa. there was also a main effect of irrelevant stimuli [f( , ) . , p . ]: only attractive faces lengthened rt relative to the baseline condition ( p . ). an anova showed a sig- nificant four-way interaction [f( , ) . , p . ]. separate anovas for the two visual fields revealed that the effect of irrelevant stimuli was present when faces were presented in the left visual field [f( , ) . , p . ], but not when they were presented in the right visual field ( p . ). results from presentations in the left visual field r t ( m se c) a attractive unattractive baseline valid invalid * * * * r t ( m se c) b valid invalid figure . mean reaction time (rt) in experiment as a function of irrelevant stim- uli and cue validity (soa msec). error bars represent standard errors. (a) face on the left and target in the right visual field. (b) face on the right and target in the left visual field. sui and liu faces delayed the rts more than did the baseline condition [ts( ) . and . , ps . and . ]. however, there was no difference between the results for attractive and unattractive conditions ( p . ). table shows the proportion of trials on which an eye movement was made to the target or irrelevant stimuli fol- lowing the onset of the central cue. there was no signifi- cant main effect of irrelevant stimuli [f( , ) . , p . ] or interaction between irrelevant stimuli and cue valid- ity [f( , ) . , p . ]. the results showed that eye movements occurred infrequently in all conditions, varying between % and % of trials across the participants. the data were collapsed across cue validity, because the overall eye movements to the cued and uncued positions did not differ from each other [f( , ) . , p . ]. our results are consistent with hawkins et al. ( ), who also found no systematic eye movements toward the cued location. the results suggest that the effect of facial attractiveness was not due to foveal fixation on the target or face stimuli, regardless of whether the cue was valid or invalid. the accuracy results in experiments – did not show significant differences between the attractive and unattract- ive face conditions ( ps . ). the interactions involving irrelevant stimuli and other conditions (cue validity, soa, and visual field) were also not significant (all ps . ). discussion our results showed that the presence of attractive faces in these experiments had a detrimental effect on the speed . , p . ] was shown with the target. again the effect was observed only when the cue was valid. when the cue was invalid, rts for the attractive and unattractive face conditions did not differ ( p . ), although both attrac- tive and unattractive face conditions delayed response to the target relative to the baseline condition [ts( ) . and . , ps . and . , respectively]. experiment showed that the facial attractiveness ef- fects found in experiment can survive a reduction of the presentation time for the face and target from to msec, but only if the face stimuli are presented to the left visual field. experiment the rt results are shown in figure . because there were no significant interactions involving visual field and irrelevant stimuli (all ps . ), the data from the two visual fields were combined in the subsequent analyses. there was a significant main effect of irrelevant stimuli [f( , ) . , p . ]. there was also a significant interaction between irrelevant stimuli and cue validity [f( , ) . , p . ]. as in experiments and , the main effect of irrelevant stimuli was significant in the valid cue condition [f( , ) . , p . ]. the sub- sequent pairwise comparisons showed that attractive faces delayed the rts more than did unattractive faces or the baseline condition [ts( ) . and . , ps . and . , respectively]. in the invalid condition, there was a significant main effect of irrelevant stimuli [f( , ) . , p . ], where both attractive and unattractive r t ( m se c) attractive unattractive baseline valid invalid * * * * figure . mean reaction time (rt) in experiment as a function of irrelevant stim- uli and cue validity (soa msec). error bars represent standard errors. table proportion of trials on which an eye movement was made to the target or to irrelevant stimuli following the onset of the central cue participant target attractive face target unattractive face target baseline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . can beauty be ignored? author note this research was supported by a grant from the royal society, a marie curie incoming international fellowship, and a grant from the natural science foundation of china (project ). we thank david per- rett for offering the face stimuli, tim alexander and the reviewers for comments on an earlier version of the manuscript, and malathy renga- mani and bryony hughes for data collection. address correspondence to j. sui, department of psychology, university of hull, cottingham road, hull hu rx, england (e-mail: jie.sui@hull.ac.uk). references aharon, i., etcoff, n., ariely, d., chabris, c. f., o’connor, e., & breiter, h. c. ( ). beautiful faces have variable reward value: f mri and behavioral evidence. neuron, , - . funes, m. j., lupiáñez, j., & milliken, b. ( ). separate mecha- nisms recruited by exogenous and endogenous spatial cues: evidence from a spatial stroop paradigm. journal of experimental psychology: human perception & performance, , - . hawkins, h. l., hillyard, s. a., luck, s. j., mouloua, m., down- ing, c. j., & woodward, d. p. ( ). visual attention modulates signal detectability. journal of experimental psychology: human perception & performance, , - . ishai, a. ( ). sex, beauty and the orbitofrontal cortex. international journal of psychophysiology, , - . johnston, v. s. ( ). mate choice decisions: the role of facial beauty. trends in cognitive sciences, , - . kanwisher, n., mcdermott, j., & chun, m. m. ( ). the fusiform face area: a module in human extrastriate cortex specialized for face perception. journal of neuroscience, , - . kranz, f., & ishai, a. ( ). face perception is modulated by sexual preference. current biology, , - . langlois, j. h., kalakanis, l. e., rubenstein, a. j., larson, a. d., hallam, m. j., & smoot, m. t. ( ). maxims or myths of beauty? a meta-analytic and theoretical review. psychological bulletin, , - . locher, p., unger, r., sociedade, p., & wahl, j. ( ). at first glance: accessibility of the physical attractiveness stereotype. sex roles, , - . mäkelä, p., näsänen, r., rovamo, j., & melmoth, d. ( ). iden- tification of facial images in peripheral vision. vision research, , - . melmoth, d. r., kukkonen, h. t., mäkelä, p. k., & rovamo, j. m. ( ). the effect of contrast and size scaling on face perception in foveal and extrafoveal vision. investigative ophthalmology & visual science, , - . o’doherty, j., winston, j., critchley, h., perrett, d., burt, d. m., & dolan, r. j. ( ). beauty in a smile: the role of medial orbitofrontal cortex in facial attractiveness. neuropsychologia, , - . olson, i. r., & marshuetz, c. ( ). facial attractiveness is ap- praised in a glance. emotion, , - . palermo, r., & rhodes, g. ( ). are you always on my mind? a review of how face perception and attention interact. neuropsycho- logia, , - . rayner, k. ( ). eye movements in reading: perceptual and lan- guage processes. new york: academic press. rhodes, g. ( ). the evolutionary psychology of facial beauty. an- nual review of psychology, , - . ro, t., russell, c., & lavie, n. ( ). changing faces: a detection advantage in the flicker paradigm. psychological science, , - . van strien, j. w., & valstar, l. h. ( ). the lateralized emotional stroop task: left visual field interference in women. emotion, , - . winston, j. s., o’doherty, j., kilner, j. m., perrett, d. i., & dolan, r. j. ( ). brain systems for assessing facial attractiveness. neuropsychologia, , - . (manuscript received january , ; revision accepted for publication september , .) of judgment for the target orientation. the participants’ voluntary allocation of covert attention to the target in- duced by the central cue was more attenuated by an attrac- tive face than by a less attractive one, even though it was task irrelevant. the speedy detection of facial beauty is consistent with previous findings (locher, unger, socie- dade, & wahl, ; olson & marshuetz, ). when the presentation time for the target and the face image was reduced from msec (experiment ) to msec (experiment ), the effects of facial attractive- ness on spatial attention were found only when the face image was presented to the left visual field. this result suggests a right-hemisphere advantage for processing fa- cial beauty. it may echo the right hemisphere’s dominance in processing facial and emotional information (e.g., kanwisher, mcdermott, & chun, ; van strien & valstar, ). future imaging studies should help local- ize the sites in the right hemisphere that have led to the difference between the results of right and left visual field presentations. in all three experiments, the effect of facial attractive- ness was found only when the central cue was valid. when it was invalid, there was no difference between the results in the attractive and unattractive face conditions. this may have been due to the fact that attention in the invalid cue trials already had been directed to the face rather than to the target. participants had to reorient attention to the tar- get after this. the effect of attractive faces may rely on a shift of spatial attention that was oriented elsewhere. the experiments also revealed that the facial attractive- ness effect was primarily associated with the short soa ( msec). it is not entirely clear why the same effect was not found in the long soa ( msec). it is possible, however, that the participants were better prepared after a long soa to focus more robustly on the target. indeed, the overall rts were faster in this soa condition. the attentional bias for attractive faces found in this study signals their biological significance. researchers have suggested that the preference for attractive faces is deeply rooted in evolution (langlois et al., ; rhodes, ). this darwinian approach helps to explain why attractive faces could receive more attention. some re- searchers have shown that attractive faces carry important information about mate quality (johnston, ). there has been evidence that, although males and females both rate beautiful male and female faces as attractive, their re- ward circuitry and related brain regions are more strongly activated by faces of the opposite gender (aharon et al., ; ishai, ). however, whether the present finding is modulated by face gender remains to be seen. due to the limited numbers of trials and of male participants, the present design made it difficult to perform this analysis. this issue will be subject to future investigations. in summary, our study shows that facial beauty is a powerful stimulus that competes with other visual infor- mation for spatial attention. the findings imply that the effect of facial attractiveness extends beyond explicit so- cial behavior and has profound impact right from the entry point of cognitive processing. << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated v % \ eci\ ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjobticket false /defaultrenderingintent /perceptual /detectblends true /detectcurves . /colorconversionstrategy /srgb /dothumbnails true /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel 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/monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /createjdffile false /description << /ara /bgr /chs /cht /cze /dan /esp /eti /fra /gre /heb /hrv (za stvaranje adobe pdf dokumenata najpogodnijih za visokokvalitetni ispis prije tiskanja koristite ove postavke. stvoreni pdf dokumenti mogu se otvoriti acrobat i adobe reader . i kasnijim verzijama.) /hun /ita /jpn /kor /lth /lvi /nld (gebruik deze instellingen om adobe pdf-documenten te maken die zijn geoptimaliseerd voor prepress-afdrukken van hoge kwaliteit. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /pol /ptb /rum /rus /sky /slv /suo /sve /tur /ukr /enu (use these settings to create adobe pdf documents best suited for high-quality prepress printing. created pdf documents can be opened with acrobat and adobe reader . and later.) /deu >> /namespace [ (adobe) (common) ( . ) ] /othernamespaces [ << /asreaderspreads false /cropimagestoframes true /errorcontrol /warnandcontinue /flattenerignorespreadoverrides false /includeguidesgrids false /includenonprinting false /includeslug false /namespace [ (adobe) (indesign) ( . ) ] /omitplacedbitmaps false /omitplacedeps false /omitplacedpdf false /simulateoverprint /legacy >> << /addbleedmarks false /addcolorbars false /addcropmarks false /addpageinfo false /addregmarks false /convertcolors /converttocmyk /destinationprofilename () /destinationprofileselector /documentcmyk /downsample bitimages true /flattenerpreset << /presetselector /mediumresolution >> /formelements false /generatestructure false /includebookmarks false /includehyperlinks false /includeinteractive false /includelayers false /includeprofiles false /multimediahandling /useobjectsettings /namespace [ (adobe) (creativesuite) ( . ) ] /pdfxoutputintentprofileselector /documentcmyk /preserveediting true /untaggedcmykhandling /leaveuntagged /untaggedrgbhandling /usedocumentprofile /usedocumentbleed false >> ] >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice library trends v. , no. building the beginnings of a beautiful partnership kathy sullivan, warren taylor, mary grace barrick, and roger stelk abstract the authors describe the process leading to, and the outcome of, their partnership to build and operate a , square foot public/ community college joint use library. located in westminster, colo- rado, the college hill library serves a population of approximately , westminster residents and , front range community college faculty and staff. the partnership began in to inves- tigate the feasibility of building the facility, which opened in april and continues to be successful today. the authors provide infor- mation on the main points of the intergovernmental agreement to build and operate the facility and relate their experiences during the planning, construction, and initial year of operation of the library. they discuss issues relating to combining staff, automation systems, and collections as well as special challenges in publicizing the library to the community. an update on the current state of the partnership is provided by the current co-directors of the library. introduction on april , , the college hill librar y opened its doors to the public for the fi rst time. this one library facility would serve as the central library for two agencies: the city of westminster, colorado, a suburban city of , located ten miles from denver, colorado; and the westminster campus of front range community college (frcc), the largest campus of the largest community college in colorado. front range community college is one of several community colleges making up the colorado com- munity college system. the colorado community college system serves library trends, vol. , no. , spring (“dual-use libraries,” edited by sarah mcnicol), pp. – © the board of trustees, university of illinois library trends/spring more than , students statewide. front range community college serves more than , students. the community colleges were established to provide two-year programs and degrees for students. hopes were high, on grand opening day, that the new building would meet the needs of both communities in a way that two, smaller separate buildings would not have been able to do. several years of working together had established the beginnings of a partnership between the two libraries that would come together in this building, a partnership that could lead to further expansion of library services for students and public library users alike. but the project also had its risks. few joint academic/public libraries existed anywhere in the country at the time, and some that had been attempted were later abandoned. the two agencies had many obstacles to overcome, such as different missions, fi scal calendars, sources of funding, policies, personnel rules, and computer systems. so why did the city of westminster and front range community college undertake such a venture? and, seven years on, has this partner- ship been a success? we will try to answer these questions from the point of view of the library’s customers and staff, and the larger community, as well as from our (kathy sullivan and warren taylor) own as its adminis- trators for its fi rst six years of operation, with an added update on the last nine months from the two current co-directors of the library, mary grace barrick and roger stelk. when our two parent organizations asked us, as library directors, to evaluate the feasibility of building a joint library, we were intrigued, ex- cited, and a more than a little nervous. both the college and the city were in desperate need of more library space. the city was then operating two small (approximately , square feet each) buildings to serve a commu- nity that was approaching , people, with no facility located in the area where most of the population now resided. city offi cials and library staff had spent several years developing plans to build a new library within a mile of the community college campus, near the geographic center of westminster. the college had a facilities master plan indicating the need for , square feet and had already started planning to build a new facility within its main campus building. the funds needed to build a new college library would be provided from the state of colorado general fund, based on this approved facilities master plan. funding was limited for both agen- cies, and neither had the wherewithal to build a library that would serve as the focal point of information and reading for its community. the idea of a possible joint facility originated with dr. tom gonzales, then frcc president, and bill christopher, then westminster city manager. the city and college had enjoyed a long relationship of cooperation on mutually benefi cial enterprises, for example, building a performing arts center and developing courses in golf course management in conjunction with the city golf courses. frcc administrators knew of an existing joint use library in broward county, florida, that seemed to be working well. library staff were asked to evaluate the idea to see whether it could work in westminster. the staff knew we were being asked not only to cooperate in the building of a new library but also in a brand new partnership that would interconnect our operations, policies, and services for years to come. it was exciting to envision a partnership that, by combining our resourc- es, could result in one library building that would provide the full range of public and community college library services for all. but could such a library actually work in reality? how dependent or independent would the two libraries be? would there be constant confl icts between user groups (for example, college students and preschoolers)? would the two libraries merge to become one, or function more as next-door neighbors? could we peacefully coexist, offering complementary services and collections that would enhance each library’s own? or would the new partnership result in never-ending headaches for the managers and animosity between the two staffs? what about parking, and the fact that the college and city are on different fi scal calendars? should the two collections be integrated or separate? should the collections use library of congress (lc) classifi cation or the dewey decimal system, or both? and what kind of computer system would be needed in such a facility? the partnership begins the fi rst step taken to attempt to answer these and other questions was a visit to broward county, florida. broward county and broward community college were already operating two joint facilities at the time—the south regional facility, built ten years before our visit, and the north regional facility in coconut creek, which had just opened when we visited in the spring of . front range community college and city of westminster librar y staff and administrators, westminster city councillors, and the chair of the westminster library board all made the trip to see how well this joint library worked. all were impressed by how well the community college and public library resources had been combined at the north regional facility—resulting in a building that was attractive, inviting, and functional for both user groups. the staffs at both the south regional and north regional libraries gener- ously shared their intergovernmental agreement with us and were candid about the pros and cons of their arrangements. our delegation returned from this trip much more excited about the potential of a combined library and less nervous about the possible pitfalls. after the broward visit, several other models were also reviewed, providing a good framework from which to develop a workable model for front range community college and the city of westminster. the remainder of that spring and summer was spent in serious negotia- tion about how the new library would be owned, operated, paid for, and sullivan et al./building partnership library trends/spring managed. careful negotiation was required to resolve more contentious issues such as the ownership, location, and name of the building and the catalog system to be used. some of the major negotiation points included the following: • the building would be located on the college campus but would be separate from the main campus building. it would be located to pro- vide easy access from the west parking lot (the one least used by college students), highly visible and identifi able from the main road, and with covered access from the main campus building. • all public space in the library would be open to use by all. • the building would be owned by the state of colorado. the intergov- ernmental agreement granting the city its share of the building would be in effect for fi fty years, with a renewal clause if both parties should wish to continue the arrangement beyond that time. • the college would pay for percent of the cost of building the , square foot facility and use percent of the building space for its ser- vices. the city would pay the remaining percent for its portion of the space. • the city and college would share equally the cost of an additional park- ing lot to provide approximately additional parking spaces. • each agency would purchase and own furnishings, equipment, and supplies. • the college would provide building maintenance, utilities, telephone ser vice, security, janitorial ser vices, grounds maintenance, and snow removal and bill the city for percent of the annual cost. • each party would budget for, purchase, and manage their own collec- tions. • the library would be operated with one computer network, to be agreed upon by the two library directors. • management of the two librar y operations would be determined by the two library directors, but with as little duplication of services and functions as possible. • a plan to dissolve the arrangement was also included in the intergov- ernmental agreement. the building gets underway in august the colorado state board for community colleges and occupational education and the westminster city council approved an intergovernmental agreement to jointly build and operate the library. the college had already hired the architectural fi rm of bennett, wagner, and grody to begin designing their new space. the city entered into a third-party agreement with the architects to add approximately , square feet for public library services in a building separated from the main campus build- ing, and to integrate the building programs of the two entities to provide convenient access to services for both user groups. after much debate about where to locate a single entrance to the build- ing, the architects proposed a two-story building with two entrances. the lower-level entrance would face the main street in front of the campus, and be accessible from the west parking lot, which was least used by college stu- dents. the upper-level entrance would face the main campus building and connect to that building by an enclosed walkway. given both the size of the building and the desire to provide easy access for both college students and the general public, both parties agreed that this was the best solution. the architects also designed a long, gently curved wall on the northwest side of the building with large windows, providing a panoramic view of the rocky mountains from both levels. on the lower level, a public meeting room, circulation services, the children’s library, new books area, audio and videotapes, a small newspaper and magazine browsing area, and large print books were all located close to the entrance. on the upper level, circulation/reserves, the reference desk and collection, the college’s non- fi ction collection, media services, and the library instruction room would be located close to the upper level entrance, most used by college faculty and students. meanwhile, city and college library staff task forces met to discuss wheth- er to integrate the college’s nonfi ction collection (classifi ed in lc) and the city’s more general nonfi ction collection (classifi ed in dewey decimal). because there was little subject overlap between the two collections, and considering the cost of a retrospective conversion, the two staffs decided to classify and shelve the nonfi ction collections separately but to incorporate all items in one database. all the city’s collections were housed on the lower level, with the exception of reference materials purchased by the city, which would be classifi ed using lc and added to the shared reference collection on the second fl oor. other amenities located on the lower level included the friends of the library gift shop, fi ve group study rooms accommodating six to ten people each, the rocky flats reading room (paid for and staffed by the u.s. department of energy), and the technical services departments of both libraries, operating side by side. on the upper level were placed adminis- trative offi ces for both libraries, the media center, a large public meeting room, a conference room, fi ve more group study rooms, a distance-learn- ing classroom, and instructional services. the lower level was designed as the noisier, popular materials fl oor, while the upper level was reserved for quieter, more research-oriented use. the architects met with staff from both libraries to address specifi c issues related to building design and function. open access to the whole of the library by all users was the underlying principle that guided our decisions. any library user could enter the building at either entrance, return and sullivan et al./building partnership library trends/spring check out their materials at either circulation desk, reserve a group study room on either fl oor, and use any of the library’s computers (for example, most children preferred to use computers in the children’s library, but they were also welcome in the reference area on the second fl oor). the two large meeting rooms (one on each level) were both open to use by college, city, or other community groups. to facilitate administration of these rooms, a room scheduling software module was purchased jointly by the two agencies, and room rental fees were divided equally. fundraising for enhancements as plans for the facility took shape, it became more and more apparent that this exciting facility would be a major asset to the community. the facil- ity would have ample space, state-of-the art equipment, beautiful interior fi nishes, and lovely views of the mountains. the college and city were also contributing funds for attractive, comfortable furniture, and percent of the project budget was set aside for purchasing art for the building. how- ever, there were still several “wish list” items beyond the budgets of either institution, so a joint fundraising committee was formed. westminster is not a particularly affl uent community, with no established philanthropic tradition, and the community college had done some fund- raising but was still fi nding its way in this area as well. a realistic goal of $ , was raised, and a list of enhancements generated to get prospective donors excited. the college’s development offi ce headed the campaign, and it was agreed that funds would be held in a college account that had already been set up for gifts. the fundraising committee identifi ed oppor- tunities to name rooms for signifi cant contributions (ranging from $ , for a small group study room to $ , for a large meeting room), and a donor wall was planned to acknowledge all contributions both large and small. through the combined efforts of college and city community members, $ , was raised by the end of the construction project. these funds were used to provide a beautiful wooden castle-like structure in the middle of the children’s library, to commission two large murals for the children’s library (painted by local children’s author janet stevens), and to purchase enhanced student and instructor workstations for the computer instruc- tion room. all individuals, businesses, and organizations were listed on the donor wall, creating a great sense of community pride and ownership in the new library and building excitement about its opening. automation a major challenge in planning the new library was the choice of an automated system that would serve the needs of both libraries. the two libraries contracted with dnr, a technology-consulting fi rm based in chi- cago. the consultant examined various options, including migrating the college’s data (located on a carl system) to the city’s existing dynix system (or vice versa), purchasing a new system to ser ve both entities, or each agency retaining their own separate system. the consultant sent out rfps to dynix, carl, and several other major vendors to determine the costs of each option. as it turned out, the cost of upgrading and expanding the city’s dynix system to include front range’s holdings was by far the least expensive option, and it met the requirements of both agencies as well as any of the vendors could, so that option was chosen. the city and college shared the cost of the upgrade/expansion and the cost of connecting the new librar y via a t- line to the ser ver, located at the westminster city hall. the city later replaced this t- line with fi ber optic cable, at no cost to the college. the city librar y’s automation staff, veronica smith and eric sisler, handled ongoing automation issues. the job descriptions for these two city positions included planning for and managing library automation for both the city and college libraries. in return, frcc bore responsibility for providing a position to head reference services for both agencies and to provide most of the reference desk staffi ng. over the years, the city’s automation team worked with both staffs to make annual decisions about shared electronic resources, to write and update internet policies, and to negotiate the purchase of new technologies such as self-checkout units, an electronic notifi cation system (dynix telecirc), and an upgrade from the dynix to the horizon integrated library system. staff reactions overcoming the concerns of the staff as the project began was some- thing of a challenge for both institutions. both staffs feared that the joint library would result in their jobs being eliminated. barring that, they were still concerned that the service ethic, level of expertise, or work methods of the “other” group would be a problem. the old stereotypes about how college librarians and public librarians differ in their approaches to service had to be overcome. college library staff would be facing some new chal- lenges, like learning to work with a new integrated library system (dynix), dealing with collecting fi nes for overdue materials, and learning to work with many more children in the building. similarly, public librar y staff would need to learn to answer more complicated reference questions, give formal classes in the library instruction room, and deal with the unique needs of college students. as soon as the intergovernmental agreement was approved and plan- ning began, staff from both agencies began meeting on a frequent basis on task forces formed to address various operational and policy issues. both staffs also attended a one-day team building retreat where integrated groups of staff were broken into teams to complete various exercises. as the two staffs interacted on a regular basis, it became apparent that sullivan et al./building partnership library trends/spring they had much more in common than they had previously imagined. the circulation task force found that only a few minor changes needed to be made in order to create consistent loan policies. the loan periods for most items were already quite similar, and the dynix system was able to specify separate loan periods for unique collections such as college reserves. the reference services task force found more similarities than differences in internet policies, printer charges, etc. the interlibrary loan committee came up with a way to share the work of processing interlibrary loan requests that was easy to understand, effi cient, and fair. library staff were consulted at every step of the process to design and develop the library. by the time the library opened, both staffs had already learned how to work together and felt very comfortable with each other. in the seven years since the library opened, issues and concerns between the two staff groups have occasionally come up, but not to any greater ex- tent than would normally be expected between different working groups in any library. staff also learned a great deal from one another and coop- erated to better serve children, non-english speakers, and remote users. there were very few times when we, as co-directors, needed to spend time resolving issues among the staff. the biggest challenge for each agency was, and continues to be, identifying developments within each agency that might affect the other agency’s staff and communicating those ap- propriately. as the operation of both libraries is affected by any decisions made, sensitivity is required and the personalities of the two directors can play an important role. building access one of the most formidable challenges posed by the joint library proj- ect was how to make room for the additional vehicles visiting the public library. the parking situation on the college campus varied by the time of year and time of day. during the fi rst few weeks of each semester, all the parking lots regularly fi lled up, and the college’s security force needed to provide parking on grassy areas as well. during most other times, ample parking was available in the west parking lot. providing “designated parking” for public library patrons was impos- sible, because any college student or faculty member could also be a public library patron. to address the additional demand, the two agencies decided instead to jointly fund an additional parking lot on the far northeast side of the campus. this parking lot would provide an additional spaces for college students, faculty, and staff, freeing up parking spaces in the west lot for public library patrons. the new lot was opened just prior to spring semester . although parking has presented diffi culties during the fi rst few weeks of each semester at certain peak hours, the arrangement has been working well the rest of the time. spreading the word at , square feet, the college hill library would be the largest in the area between denver and boulder, colorado. the size of the project, and its innovative nature, generated excitement in the community. the biggest public relations challenge was to inform the public that the new librar y really would be a public librar y open to all, despite its location on the college campus. to that end, we planned a major groundbreak- ing ceremony and a grand opening day celebration with many children’s entertainers, multicultural dance groups, refreshments, and giveaways, to which each agency equally contributed. we highlighted our large and beautiful children’s library to send the message that this was defi nitely more than a college library. we placed a multipage, full-color insert in the local paper and sent extra copies of the insert to all residents who lived within close range of the new library. the city of westminster’s newspaper, city edition, featured stories about the new library in several issues: when the intergovernmental agreement was signed; after the groundbreaking; and close to the time of our opening. after the grand opening celebration on april , , business began to pick up signifi cantly, and by the time the westminster public library’s summer reading program for children started in june, word of the beauti- ful new children’s library had spread. young families heavily populate the residential areas around the new library, and this fact is refl ected in our children’s circulation statistics. excited parents and children found the library fi rst, and word spread from there. front range community college students and faculty have also made heavy use of the new librar y since its opening. the additional seating, meeting room, and study spaces have relieved the overcrowding that was a constant problem in the former library. the two libraries’ combined ref- erence, periodical, and electronic database collections offer more for the students than either library could have offered on its own. many students with children are regular users of the children’s library, and high school students are using the college’s large media collection and reference collec- tion. less than two years after opening its doors, college hill celebrated its millionth patron visit, and the two millionth patron milestone was reached after another year had passed. pros and cons after seven years of operation, the pluses and minuses of this joint ven- ture are now clear. the facility has been amazingly popular, with checkouts of public library materials alone reaching , , for the year . the public library has been able to make regular use of the computer instruction room to offer a variety of classes to the public. the whole range of college and public library materials is available under one roof, and the building sullivan et al./building partnership library trends/spring offers much more space and seating for each group during the many times when the building is chiefl y used by the public (term breaks and holidays) or by the students/faculty (early mornings). staff from the two libraries have worked together to sponsor cultural programs, solve problems, and deal with diffi cult issues such as internet policies. on an informal basis, collection development staff cooperate in their selection decisions, stretch- ing both agencies’ budgets a little farther. very few problems have come up between the two staffs, and those that have were quickly resolved. on the negative side, making joint decisions about building mainte- nance and security expenses can sometimes be tricky because the budget cycles of the two institutions are very different. scheduling the public meet- ing rooms has required greater staff involvement and has required more staff time than previously thought. some decisions can be more complicated because there are more parties involved (for instance, some information technology [it] decisions can require approval from it administrators on both sides). but on the whole, the experience of sharing this library has been overwhelmingly positive to date, and staff continue to be committed to making it remain so for many years to come. an update on college hill this article concludes with updates from the new college library direc- tor and the public library manager, both of whom were new to their posts in . observations of the new college library director beyond the benefi t of being able to work in this beautiful facility, anoth- er factor in accepting this position was the knowledge that both the public library manager and i would be new to our positions. from my perspective, this unique circumstance would lend itself to a comprehensive examina- tion on our part of the policies and procedures associated with the joint use operation. knowing that the ongoing success of any library depends upon fl exibility, innovation, and a constant reassessment of community needs, this type of analysis will afford us the opportunity to build upon the success of the current arrangement. the monthly meetings scheduled with my counterpart and our respective supervisors underscore this, and it certainly demonstrates the city’s and college’s commitment to maximizing the effectiveness of this operation. of course, one factor that will never change is that the joint use part- nership between the city and the college does lead to a certain degree of accommodation on the part of both libraries. as one would suspect, compromise is the mantra of any joint use partnership, and it is routinely developed here to facilitate the different missions of each library as well as the specifi c needs of its clientele. these compromises can place limits on the fl exibility of each organization, and, at times, may impact the abil- ity of each to focus exclusively on its primary mission. however, on a daily basis our patrons clearly remind us that the pros of this partnership by far outweigh any of the negative consequences. update from the new public library manager nine months ago, when i took over as the manager for the public library side of this joint facility, we faced a challenge. the former man- ager of the westminster public library had relocated to england, and the director for the front range community college library had retired the same summer. with this, we lost the informal history of how the staffs had worked together over the years to provide service. there was concern that we had lost the story of our joint facility. each side of the house had new leaders who needed to learn the unique aspects of their jobs as related to their specifi c employer. this newness was combined with the tension of the westminster public library opening a new, very busy branch library. whereas in the past the college hill library had been the primary focal point for staff and services, the new branch library pulled away part of that focus. the shared it staff —part of our joint operating agreement—now needed to spend a signifi cant part of the year getting the branch library up and running. with so many adjustments to make, our tendency was to revert to an “us” and “them” mentality, leading to a feeling that we were two tenants sharing the same building instead of a joint facility. to ameliorate this sense of drifting from our joint mission, both directors have worked to reinstate some ideas from the early days of the partnership, for example, joint staff meetings, joint meetings to discuss automation issues, and joint adult reference meetings. additionally, the two managers and our supervisors meet for breakfast once a month to discuss the long-term plans of the city and the college. plans are in the works to draw up a new joint mission statement, allowing a recycling of sorts, by taking the best from our past and tying it into our future. note . see http://frontrange.edu for more information. . see http://www.broward.edu/libraries/index.jsp and http://www.broward.edu/ libraries/pine/index.jsp for more information. kathy sullivan is the area manager, cheltenham and tewkesbur y libraries for gloucestershire county libraries in the u.k. prior to her recent move to the u.k., kathy was the library services manager for the city of westminster for years. she received her undergraduate degree from bowling green state university, ohio, and her m.l.s. from the university of arizona. warren taylor was born and raised in denver, colorado, usa. warren earned a master of arts degree in library science from the university of denver. he also sullivan et al./building partnership earned a master of arts degree in anthropology from the university of colorado. in addition warren earned a ph. d. in higher education administration from the university of denver. he retired as director of the library, media center and center for instructional design and development at front range community college. prior to that warren served as director of facilities use, research and planning at the auraria higher education center. dr. taylor was the assistant director and tenured assistant professor at the auraria library and the university of colorado at denver. he taught in the school of business at the university of colorado at denver as well as the computer information systems program at front range community college. mary grace barrick is the library manager for the city of westminster colorado libraries. she received her undergraduate degree from the university of michigan, and her m.s.l.s. from wayne state university in detroit. she has worked in academic, community college, medical and public libraries. roger stelk is currently the director of library services at front range community college, westminster co. before arriving at the college hill library, stelk worked as the coordinator for collection development at depaul university, as the director of public services for hunter library at western carolina university, as the coordinator of the reference/information desk in love library at the university of nebraska- lincoln, and as a reference librarian/bibliographer for newman library at virginia tech. stelk is a member of the american library association, the association for college and research libraries, and the colorado association of libraries. he has served on several ala/acrl committees and is the co-author of a number of ar- ticles on libraries. stelk has a masters in library and information science from the university of illinois at urbana/champaign as well as a ma and ba from southern illinois university-carbondale. library trends/spring lifetime and production rate of beauty baryons from z decays hal id: in p - http://hal.in p .fr/in p - submitted on jun hal is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. the documents may come from teaching and research institutions in france or abroad, or from public or private research centers. l’archive ouverte pluridisciplinaire hal, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. lifetime and production rate of beauty baryons from z decays p. abreu, w. adam, t. adye, e. agasi, i. ajinenko, r. aleksan, g d. alekseev, p p. allport, s. almehed, s j. alvsvaag, et al. to cite this version: p. abreu, w. adam, t. adye, e. agasi, i. ajinenko, et al.. lifetime and production rate of beauty baryons from z decays. zeitschrift für physik c particles and fields, springer verlag, , , pp. - . �in p - � http://hal.in p .fr/in p - https://hal.archives-ouvertes.fr european organization for nuclear research cern{ppe/ { april lifetime and production rate of beauty baryons from z decays delphi collaboration abstract the production and decay of beauty baryons (b-baryons) have been studied using : � z hadronic decays collected by the delphi detector at lep. three di�erent techniques were used to identify the b-baryons. the �rst method used pairs of a � and a lepton to tag the b-baryon decay. the second method associated fully reconstructed �c baryons with leptons. the third analysis re- constructed the b-baryon decay points by forming secondary vertices from iden- ti�ed protons and muons of opposite sign. using these methods the following production rates were measured: f(b ! b-baryon) � br(b-baryon ! �s`��`x) = ( : � : � : )%; f(b ! b-baryon) � br(b-baryon ! �c`��`x) = ( : � : + : � : )%; f(b ! b-baryon) � br(b-baryon ! p��x) = ( : � : �+ : � : )%: the average b-baryon lifetime was determined to be: � = : +: �: (stat:) � : (exp:syst:)+: �: (th:syst:) ps. (to be submitted to zeit. f. physik c) ii p.abreu , w.adam , t.adye , e.agasi , i.ajinenko , r.aleksan , g.d.alekseev , p.p.allport , s.almehed , s.j.alvsvaag , u.amaldi , s.amato , a.andreazza , m.l.andrieux , p.antilogus , w-d.apel , y.arnoud , b.�asman , j-e.augustin , a.augustinus , p.baillon , p.bambade , f.barao , r.barate , g.barbiellini , d.y.bardin , g.j.barker , a.baroncelli , o.barring , j.a.barrio , w.bartl , m.j.bates , m.battaglia , m.baubillier , j.baudot , k-h.becks , m.begalli , p.beilliere , yu.belokopytov , a.c.benvenuti , m.berggren , d.bertrand , f.bianchi , m.bigi , m.s.bilenky , p.billoir , d.bloch , m.blume , s.blyth , v.bocci , t.bolognese , m.bonesini , w.bonivento , p.s.l.booth , g.borisov , c.bosio , s.bosworth , o.botner , b.bouquet , c.bourdarios , t.j.v.bowcock , m.bozzo , p.branchini , k.d.brand , r.a.brenner , c.bricman , l.brillault , r.c.a.brown , p.bruckman , j-m.brunet , l.bugge , t.buran , a.buys , m.caccia , m.calvi , a.j.camacho rozas , t.camporesi , v.canale , m.canepa , k.cankocak , f.cao , f.carena , p.carrilho , l.carroll , c.caso , m.v.castillo gimenez , a.cattai , f.r.cavallo , l.cerrito , v.chabaud , m.chapkin , ph.charpentier , l.chaussard , j.chauveau , p.checchia , g.a.chelkov , r.chierici , p.chliapnikov , p.chochula , v.chorowicz , v.cindro , p.collins , j.l.contreras , r.contri , e.cortina , g.cosme , f.cossutti , h.b.crawley , d.crennell , g.crosetti , j.cuevas maestro , s.czellar , e.dahl-jensen , j.dahm , b.dalmagne , m.dam , g.damgaard , a.daum , p.d.dauncey , m.davenport , w.da silva , c.defoix , g.della ricca , p.delpierre , n.demaria , a.de angelis , h.de boeck , w.de boer , s.de brabandere , c.de clercq , c.de la vaissiere , b.de lotto , a.de min , l.de paula , c.de saint-jean , h.dijkstra , l.di ciaccio , f.djama , j.dolbeau , m.donszelmann , k.doroba , m.dracos , j.drees , k.-a.drees , m.dris , y.dufour , f.dupont , d.edsall , r.ehret , g.eigen , t.ekelof , g.ekspong , m.elsing , j-p.engel , n.ershaidat , b.erzen , m.espirito santo , e.falk , d.fassouliotis , m.feindt , a.fenyuk , a.ferrer , t.a.filippas , a.firestone , h.foeth , e.fokitis , f.fontanelli , f.formenti , b.franek , p.frenkiel , d.c.fries , a.g.frodesen , r.fruhwirth , f.fulda-quenzer , h.furstenau , j.fuster , a.galloni , d.gamba , m.gandelman , c.garcia , j.garcia , c.gaspar , u.gasparini , ph.gavillet , e.n.gazis , d.gele , j-p.gerber , m.gibbs , d.gillespie , r.gokieli , b.golob , g.gopal , l.gorn , m.gorski , v.gracco , e.graziani , g.grosdidier , p.gunnarsson , m.gunther , j.guy , u.haedinger , f.hahn , m.hahn , s.hahn , z.hajduk , a.hallgren , k.hamacher , w.hao , f.j.harris , v.hedberg , r.henriques , j.j.hernandez , p.herquet , h.herr , t.l.hessing , e.higon , h.j.hilke , t.s.hill , s-o.holmgren , p.j.holt , d.holthuizen , m.houlden , j.hrubec , k.huet , k.hultqvist , p.ioannou , j.n.jackson , r.jacobsson , p.jalocha , r.janik , g.jarlskog , p.jarry , b.jean-marie , e.k.johansson , l.jonsson , p.jonsson , c.joram , p.juillot , m.kaiser , g.kalmus , f.kapusta , m.karlsson , e.karvelas , s.katsanevas , e.c.katsou�s , r.keranen , b.a.khomenko , n.n.khovanski , b.king , n.j.kjaer , h.klein , a.klovning , p.kluit , j.h.koehne , b.koene , p.kokkinias , m.koratzinos , v.kostioukhine , c.kourkoumelis , o.kouznetsov , p.-h.kramer , m.krammer , c.kreuter , j.krolikowski , i.kronkvist , z.krumstein , w.krupinski , p.kubinec , w.kucewicz , k.kurvinen , c.lacasta , i.laktineh , s.lamblot , j.w.lamsa , l.lanceri , d.w.lane , p.langefeld , v.lapin , i.last , j-p.laugier , r.lauhakangas , g.leder , f.ledroit , v.lefebure , c.k.legan , r.leitner , y.lemoigne , j.lemonne , g.lenzen , v.lepeltier , t.lesiak , d.liko , r.lindner , a.lipniacka , i.lippi , b.loerstad , m.lokajicek , j.g.loken , j.m.lopez , a.lopez-fernandez , m.a.lopez aguera , d.loukas , p.lutz , l.lyons , j.macnaughton , g.maehlum , a.maio , v.malychev , f.mandl , j.marco , b.marechal , m.margoni , j-c.marin , c.mariotti , a.markou , t.maron , c.martinez-rivero , f.martinez-vidal , s.marti i garcia , f.matorras , c.matteuzzi , g.matthiae , m.mazzucato , m.mc cubbin , r.mc kay , r.mc nulty , j.medbo , c.meroni , w.t.meyer , m.michelotto , e.migliore , l.mirabito , w.a.mitaro� , u.mjoernmark , t.moa , r.moeller , k.moenig , m.r.monge , p.morettini , h.mueller , l.m.mundim , w.j.murray , b.muryn , g.myatt , f.naraghi , f.l.navarria , s.navas , p.negri , s.nemecek , w.neumann , n.neumeister , r.nicolaidou , b.s.nielsen , m.nieuwenhuizen , v.nikolaenko , p.niss , a.nomerotski , a.normand , w.oberschulte-beckmann , v.obraztsov , a.g.olshevski , a.onofre , r.orava , a.ostankov , k.osterberg , a.ouraou , p.paganini , m.paganoni , p.pages , h.palka , th.d.papadopoulou , l.pape , c.parkes , f.parodi , a.passeri , m.pegoraro , l.peralta , h.pernegger , m.pernicka , a.perrotta , c.petridou , a.petrolini , h.t.phillips , g.piana , f.pierre , s.plaszczynski , o.podobrin , m.e.pol , g.polok , p.poropat , v.pozdniakov , m.prest , p.privitera , n.pukhaeva , a.pullia , d.radojicic , s.ragazzi , h.rahmani , j.rames , p.n.rato� , a.l.read , m.reale , p.rebecchi , n.g.redaelli , d.reid , p.b.renton , l.k.resvanis , f.richard , j.richardson , j.ridky , g.rinaudo , i.ripp , a.romero , i.roncagliolo , p.ronchese , l.roos , e.i.rosenberg , e.rosso , p.roudeau , t.rovelli , w.ruckstuhl , v.ruhlmann-kleider , a.ruiz , k.rybicki , h.saarikko , y.sacquin , a.sadovsky , g.sajot , j.salt , j.sanchez , m.sannino , h.schneider , m.a.e.schyns , g.sciolla , f.scuri , y.sedykh , a.m.segar , iii a.seitz , r.sekulin , r.c.shellard , i.siccama , p.siegrist , s.simonetti , f.simonetto , a.n.sisakian , b.sitar , t.b.skaali , g.smadja , n.smirnov , o.smirnova , g.r.smith , r.sosnowski , d.souza-santos , t.spassov , e.spiriti , s.squarcia , h.staeck , c.stanescu , s.stapnes , i.stavitski , k.stepaniak , f.stichelbaut , a.stocchi , j.strauss , r.strub , b.stugu , m.szczekowski , m.szeptycka , t.tabarelli , j.p.tavernet , o.tchikilev , a.tilquin , j.timmermans , l.g.tkatchev , t.todorov , d.z.toet , a.tomaradze , b.tome , e.torassa , l.tortora , g.transtromer , d.treille , w.trischuk , g.tristram , a.trombini , c.troncon , a.tsirou , m-l.turluer , i.a.tyapkin , m.tyndel , s.tzamarias , b.ueberschaer , s.ueberschaer , o.ullaland , v.uvarov , g.valenti , e.vallazza , g.w.van apeldoorn , p.van dam , w.k.van doninck , j.van eldik , n.vassilopoulos , g.vegni , l.ventura , w.venus , f.verbeure , m.verlato , l.s.vertogradov , d.vilanova , p.vincent , l.vitale , e.vlasov , a.s.vodopyanov , v.vrba , h.wahlen , c.walck , a.wehr , m.weierstall , p.weilhammer , a.m.wetherell , d.wicke , j.h.wickens , m.wielers , g.r.wilkinson , w.s.c.williams , m.winter , m.witek , g.wormser , k.woschnagg , k.yip , f.zach , c.zacharatou , a.zaitsev , a.zalewska , p.zalewski , d.zavrtanik , e.zevgolatakos , n.i.zimin , m.zito , d.zontar , r.zuberi , g.c.zucchelli , g.zumerle ames laboratory and department of physics, iowa state university, ames ia , usa physics department, univ. instelling antwerpen, universiteitsplein , b- wilrijk, belgium and iihe, ulb-vub, pleinlaan , b- brussels, belgium and facult�e des sciences, univ. de l'etat mons, av. maistriau , b- mons, belgium physics laboratory, university of athens, solonos str. , gr- athens, greece department of physics, university of bergen, all�egaten , n- bergen, norway dipartimento di fisica, universit�a di bologna and infn, via irnerio , i- bologna, italy centro brasileiro de pesquisas f�isicas, rua xavier sigaud , rj- rio de janeiro, brazil and depto. de f�isica, pont. univ. cat�olica, c.p. rj- rio de janeiro, brazil and inst. de f�isica, univ. estadual do rio de janeiro, rua s~ao francisco xavier , rio de janeiro, brazil comenius university, faculty of mathematics and physics, mlynska dolina, sk- bratislava, slovakia coll�ege de france, lab. de physique corpusculaire, in p -cnrs, f- paris cedex , france cern, ch- geneva , switzerland centre de recherche nucl�eaire, in p - cnrs/ulp - bp , f- strasbourg cedex, france institute of nuclear physics, n.c.s.r. demokritos, p.o. box , gr- athens, greece fzu, inst. of physics of the c.a.s. high energy physics division, na slovance , , praha , czech republic dipartimento di fisica, universit�a di genova and infn, via dodecaneso , i- genova, italy institut des sciences nucl�eaires, in p -cnrs, universit�e de grenoble , f- grenoble cedex, france research institute for high energy physics, seft, p.o. box , fin- helsinki, finland joint institute for nuclear research, dubna, head post o�ce, p.o. box , moscow, russian federation institut f�ur experimentelle kernphysik, universit�at karlsruhe, postfach , d- karlsruhe, germany high energy physics laboratory, institute of nuclear physics, ul. kawiory a, pl- krakow , poland universit�e de paris-sud, lab. de l'acc�el�erateur lin�eaire, in p -cnrs, bat , f- orsay cedex, france school of physics and materials, university of lancaster, lancaster la yb, uk lip, ist, fcul - av. elias garcia, - o , p- lisboa codex, portugal department of physics, university of liverpool, p.o. box , liverpool l bx, uk lpnhe, in p -cnrs, universit�es paris vi et vii, tour (rdc), place jussieu, f- paris cedex , france department of physics, university of lund, s�olvegatan , s- lund, sweden universit�e claude bernard de lyon, ipnl, in p -cnrs, f- villeurbanne cedex, france universidad complutense, avda. complutense s/n, e- madrid, spain univ. d'aix - marseille ii - cpp, in p -cnrs, f- marseille cedex , france dipartimento di fisica, universit�a di milano and infn, via celoria , i- milan, italy niels bohr institute, blegdamsvej , dk- copenhagen , denmark nc, nuclear centre of mff, charles university, areal mff, v holesovickach , , praha , czech republic nikhef-h, postbus , nl- db amsterdam, the netherlands national technical university, physics department, zografou campus, gr- athens, greece physics department, university of oslo, blindern, n- oslo , norway dpto. fisica, univ. oviedo, c/p. p�erez casas, s/n- oviedo, spain department of physics, university of oxford, keble road, oxford ox rh, uk dipartimento di fisica, universit�a di padova and infn, via marzolo , i- padua, italy rutherford appleton laboratory, chilton, didcot ox oqx, uk dipartimento di fisica, universit�a di roma ii and infn, tor vergata, i- rome, italy centre d'etude de saclay, dsm/dapnia, f- gif-sur-yvette cedex, france istituto superiore di sanit�a, ist. naz. di fisica nucl. (infn), viale regina elena , i- rome, italy c.e.a.f.m., c.s.i.c. - univ. cantabria, avda. los castros, s/n- santander, spain, (cicyt-aen - ) inst. for high energy physics, serpukov p.o. box , protvino, (moscow region), russian federation j. stefan institute and department of physics, university of ljubljana, jamova , si- ljubljana, slovenia fysikum, stockholm university, box , s- stockholm, sweden dipartimento di fisica sperimentale, universit�a di torino and infn, via p. giuria , i- turin, italy dipartimento di fisica, universit�a di trieste and infn, via a. valerio , i- trieste, italy and istituto di fisica, universit�a di udine, i- udine, italy univ. federal do rio de janeiro, c.p. cidade univ., ilha do fund~ao br- - rio de janeiro, brazil department of radiation sciences, university of uppsala, p.o. box , s- uppsala, sweden ific, valencia-csic, and d.f.a.m.n., u. de valencia, avda. dr. moliner , e- burjassot (valencia), spain institut f�ur hochenergiephysik, �osterr. akad. d. wissensch., nikolsdorfergasse , a- vienna, austria inst. nuclear studies and university of warsaw, ul. hoza , pl- warsaw, poland fachbereich physik, university of wuppertal, postfach , d- wuppertal , germany introduction the �b baryon was �rst observed in the exclusive decay �b ! �j= by the ua experiment at the sp�ps collider [ ]. evidence for its production in z hadronic decays has been reported by the lep experiments [ , ]. they attributed the observed correlation between �'s and leptons (`'s) to �b decays. measurements of the average b-baryon lifetime have been recently published [ , ]. its precise determination tests the theory of heavy quark decays and the simple quark-spectator model. this is of particular interest for the beauty quark [ ] where, due to the high b-quark mass, the theoretical predictions based on perturbative expansions are less uncertain than those for charm decays. this paper extends the previous analysis [ ] and adds two new semileptonic decay channels, based on the detection of a �c or a fast proton (p) in the same jet as a high transverse momentum lepton. the �` channel provides a clear signature for b-baryon production but the position of the b-baryon decay vertex is precisely determined with relatively low e�ciency. the �c` channel provides the purest b-baryon sample. finally the p` channel relies on the particle identi�cation capabilities of delphi. the delphi detector the delphi detector has been described in detail elsewhere [ ]. both charged particle tracking through the uniform axial �eld and particle identi�cation are important in this analysis. the detector elements used for tracking are: the vertex detector (vd), the inner detector (id), the time projection chamber (tpc) and the outer detector (od). the other important detectors are: the the ring imaging cherenkov detector (rich) for hadron identi�cation, the barrel electromagnetic calorimeter (hpc) and the muon chambers for lepton identi�cation. the ionization loss de=dx measurements in the tpc are also used for particle identi�cation. the vd, consisting of cylindrical layers of silicon detectors (radii , and cm), provides up to hits per track (or more in small overlapping regions) in the polar angle range o < � < o. the intrinsic resolution of the vd points is � �m, measured only in the plane transverse to the beam direction (r� plane). the precision on the impact parameter with respect to the primary vertex of a track having hits associated in the vd is � �m, measured in dimuon z events. charged particle tracks were reconstructed with % e�ciency and with a momentum resolution �p=p < : � � p (gev/c). the primary vertex of the e+e� interaction was reconstructed on an event-by-event basis using a beam spot constraint. the position of the primary vertex could be determined in this way to a precision of about �m (slightly dependent on the avour of the primary quark-antiquark pair) in the plane transverse to the beam direction. in this plane secondary vertices from beauty and charm decays were reconstructed with a precision of � �m along the ight direction of the decaying particles. the � ! p� decays could be reconstructed if the distance (in the r� plane) between the � decay point and primary vertex was less than cm. this condition meant that the proton and pion had track segments at least cm long in the tpc. hadron identi�cation relied on the speci�c ionization in the tpc and on the rich detector. the de=dx measurement had a precision of � % in the momentum range < p < gev/c. the rich detector [ ] consisted of a liquid radiator which provided p=k=� separation in the intermediate momentum region { gev/c, and a gas radiator which worked in veto mode for proton selection in the region { gev/c and separated protons from kaons for momenta less than gev/c. the barrel electromagnetic calorimeter (hpc), covered the polar angle region � < � < �, and detected electrons with an energy precision �e=e = : = p e(gev ). two planes of muon chambers covered the polar angle region � < � < �, except for two regions of � � around � = � and � = �. the �rst layer was inside the return yoke of the magnet, after cm of iron, while the second was mounted outside the yoke, behind a further cm of iron. lepton selection and hadron identi�cation hadronic events from z decays were selected by requiring a charged multiplicitygreater than and a total reconstructed energy greater than . p s; charged particles were required to have a momentum greater than . gev/c and polar angle between o and o. the overall trigger and selection e�ciency was : � : [ ]. lepton candidates in these events were used in the analysis if their momentum was greater than gev/c. . electron identi�cation the probability of any track being due to an electron was calculated using the spatial separation between the extrapolated position of a track at the hpc and the position of the nearest electro-magnetic shower, a match between the measured energy and the track momentum and a successful �t to the longitudinal pro�le of the shower in the hpc layers [ ]. tracks with a � probability greater than % for this electron hypothesis were retained for further analysis. the �nal electron sample was obtained by using additional information from the tpc and rich. the de=dx measurement in the tpc was used to check that the speci�c ionization for the track was consistent with that expected from electrons with a probability of at least %. also, when the gas rich was sensitive it was required to show at least one associated photoelectron at the correct angle for the electron hypothesis. electrons arising from photon conversions were removed by a vertex �t to pairs of electron candidates. if the e+e� invariant mass was reconstructed to be less than mev/c the pair was assumed to be a converted photon. using this procedure the electron identi�cation e�ciency in the hpc �ducial volume was found to be ( � )%, with a hadron misidenti�cation probability of ( : � : )%. . muon identi�cation the identi�cation of muons relied on the muon chambers. tracks were extrapolated to the muon chambers and a global � of the track was used to de�ne a re�tting procedure which took into account the multiple scattering between the inner tracking devices and the muon chambers. at least hit in the chamber layer outside the iron yoke and a � =ndof < were required (< in the forward region). the corresponding muon identi�cation e�ciency was ( � )% in the barrel and ( � )% in the end-caps, with hadron misidenti�cation probabilities of ( : � : )% and ( : � : )% respectively. . hadron identi�cation using the rich particle identi�cation using the delphi rich detector has been described in detail elsewhere [ ]. the three analyses presented in this paper used protons with momentum range well above the pion threshold in the gas radiator of . gev/c. above this threshold, the gas radiator worked in veto-mode for p=� separation up to gev/c, with % e�ciency and a pion rejection factor of . a k=p separation with the same background rejection power was ensured in this mode of operation between . gev/c, the gas radiator threshold for kaons, and gev/c. above this energy, identi�cation was provided by the measurement of the cherenkov angle of the detected photons using a \ring identi�cation mode" algorithm [ ], with % e�ciency and rejection factors - . this algorithm was also applied to the liquid radiator data, which provided complementary information for k=� and k=p separation in the momentum range - gev/c. the rich was operational for % of the data, % of the data and nearly % of the data sample (gas radiator only). �` channel the analysis of events with a � and a lepton is based on about . � z hadronic decays collected in the years - . decays of b-baryons with a �` pair in the �nal state originate mainly from the decay chain: b-baryon ! �c`�x;�c ! �x. these decays have the following properties: the lepton has high transverse and longitudinal momentum, the � has a harder momentum spectrum than the � produced in light quark fragmentation and the �` pair has the right sign i.e. p`� rather than p`+, where p is the proton from the � decay. in the following the lepton transverse momentum (pt ) is computed, if not otherwise stated, with respect to the jet axis de�ned including the lepton in the jet. charged particles are clustered into jets using the lund jet �nding algorithm [ ] (routine luclus) with a clustering mass parameter equal to . gev/c . semileptonic b meson decays, such as b ! �c �n`��x (where �n is an antibaryon), can also contribute to an excess in right sign pairs. this was estimated to be negligible, under the conservative assumption that % of b quarks hadronize to a b meson, using the % cl upper limit br( �b ! p`��x) < : � [ ] and the cleo result that % of the protons produced in b decays come from � particles [ ]. this conclusion takes into account the fact that the e�ciency of the selection cuts described below (section . ) for this channel is smaller by a factor than for the b-baryon decay. background events from direct c-quark production through the c ! �c ! �`�x decay chain have protons and the leptons of the same sign; in addition, the lepton pt spectrum is softer. a quantitative analysis of the background based on detailed simulation of z hadronic events is discussed in section . . . � selection in the search for � ! p� decay all pairs of opposite sign charged particles with momentum : < p < gev/c were considered. a candidate � vertex was formed if the minimum separation in the r� plane of the two tracks was less than mm and if their perigee separation in the beam direction was less than mm. if the same track was associated with more than one vertex only the vertex with the largest decay length (in the r� projection) was used. for decays inside the beam pipe at least one vertex detector hit was required per track. only combinations where the vertex was closer to the primary vertex than the starting point of both tracks were kept. particle identi�cation greatly improved the background rejection with negligible loss in e�ciency. the identi�cation criteria using the de=dx measurement in the tpc and the selections for rejection of conversions and k decays are described previously [ ]. if the extrapolation of the track of charged particle with highest momentum (assumed to be the proton) to the rich was in the sensitive volume of the detector and the rich was operational, the identi�cation algorithm described in section . was used. to improve the signal-to-noise ratio further, the following kinematic selection criteria were applied: the angle in the r� plane between the line of ight and the reconstructed � momentum was required to be smaller than � and the probability for the lifetime of the � decay candidate to be greater than that observed was required to be greater than %. figure a shows the p� invariant mass distribution for the remaining candidates with momentum greater than gev/c. in this sample the �tted � signal was � decays, with a � mass mean value of : � : mev/c and a measured width of : � : mev/c . the momentum distribution for the reconstructed � candidates with the background subtracted is shown in �gure .b for the mass range from to mev/c . it is compared with the prediction of the delphi simulation program using the jetset . model [ ] with the results analysed using the same programs as the real data. the � ! p� reconstruction e�ciency from the simulation, shown in �gure c, was ( � )% for p > gev/c. this increase in e�ciency compared with the previous delphi publication [ ] is due to improved pattern recognition. . �` correlations to select � and leptons coming from the �b decay chain, the following criteria were applied: the momentum of the �candidate was required to be greater than gev/c and the momentum of the lepton greater than gev/c. the lepton was only used if it was in the same jet as the � and its pt was greater than . gev/c. the mass of the �` combination was required to lie in the range . to . gev/c and the �` pairs were only selected for analysis if their total momentumwas greater than gev/c. in the simulation the above procedure reduced background sources of �` pairs by more than two orders of magnitude [ ] and selected �b ! �`�x decays (provided the � was reconstructed) with an e�ciency of ( � )%. the p� invariant mass spectra in the data for the right and wrong sign �` pairs are shown by the dots in �gures .a and .b, together with the result of a �t to the data using a gaussian function and a polynomial background. the �t gives a signal of ( � ) �'s in the right sign pairs and ( � ) �'s in the wrong sign pairs. the histograms show the corresponding distributions from simulation normalized to the total number of hadronic z events. the yield of genuine �'s predicted by the simulation is shown by the single hatched area; the double hatched areas show the simulation prediction for the � coming from a b-baryon decay. the simulation assumed a �b production rate f(b ! �b) � br(�b ! �`�x) = : % and a combined �b and �b production rate of . %. it also predicted a small signal in the wrong sign pair combinations, due to �c ! �`�x decays and to the associated production of �b + �� in which the �� was reconstructed and associated with the lepton. . branching ratios as shown in �gures .a,b, the simulation included a large number of �'s coming from sources other than b-baryon decays, in both right and wrong sign combinations. the absolute value was model dependent and was not used in this analysis. however the ratio (r = : � : ) of the background level of �'s in the two distributions in �gures .a and .b was assumed to be correct. the statistical error of . on this ratio was included in the systematic error on the production rate. moreover, a small b-baryon signal ( � % of the signal in the right sign sample) was predicted in the wrong sign pair sample. thus, to estimate the b-baryon yield in the right sign sample, the � signal in wrong sign combinations was subtracted from the signal in �gure a and the result scaled by the correction factor c = =( : � : ). this led to a total b-baryon signal of � (stat:) � (syst:) events. for the analysis of the �� pairs, a hadronic data sample in which the tpc and the barrel and forward muon chambers were more than % operational was used. this selected , , z events. the overall e�ciency for the �� channel was ( : � : )%. the estimated number of b-baryons in this sample ( � � ) leads to a production rate: f(b! b-baryon) � br(b-baryon! ��x) = ( : � : + : � : )%. for the analysis of the �e pairs, the hadronic data sample in which the tpc and hpc were more than % operational was used; this requirement selected , , z events. the overall e�ciency for the �e channel was ( : � : )%. the estimated number of b-baryons in the sample was ( � � ), giving a production rate: f(b! b-baryon) � br(b-baryon! �e�x) = ( : � : + : � : )%. assuming lepton universality, these results may be averaged to give: f(b! b-baryon) � br(b-baryon! �`�x) = ( : � : � : )%. table shows the contributions from di�erent sources to the total systematic uncer- tainty. the e�ciency of the selection de�ned by the kinematic cuts discussed in section . was dependent on the momentum spectrum, the polarization and the decay model assumed for the b-baryon. the polarization value quoted in the table is the central one of the allowed range [- . , . ], where the lower limit is the standard model predic- tion for the polarization of the original b quark, assuming sin �w = : . the b-baryon semileptonic decay was simulated in the framework of heavy quark e�ective theory [ ] using the following parameterization of the isgur-wise function: �(!) = exp[aiw( � !)]; where ! = v�b � v�c and v�b (v�c) is the b-baryon (c-baryon) -velocity. a further e�ect arose if resonant and non-resonant �b ! �cn�`� decays were an important fraction of the total width, where n is a positive integer. finally, di�erent assumptions about the �c ! �x branching fractions gave negligible e�ects on the overall e�ciency. as can be seen from the table, the dominant contribution to the systematic error comes from the background subtraction procedure used to eliminate accidental �` correlations. the above result can be compared with the previous determination by delphi [ ]: f(b ! �b) � br(�b ! �`�x) = ( : � : (stat:) � : (syst:))%. figure a shows the right-sign � momentum spectrum after the subtraction of the wrong sign �sample for the data (dots); the superimposed histogram, showing the simu- lation prediction for the momentum of reconstructed � originating from a b-baryon, was in good agreement with the observed spectrum. similar plots for the lepton pt spectrum, the sum of the lepton and � momenta and the �` invariant mass are shown in �gures .b-d. table : contributions to the total systematic uncertainty on the b-baryon production rate times its branching ratio to �`�x. source variation level syst:uncertainty(� ) lepton identi�cation e�ciency � % � : � reconstruction e�ciency : � : � : background subtraction � � : < eb > =ebeam : � : � : �(!) = exp[aiw ( � !)] aiw = : + : � : � : �b polarization � : � : � : br(�b ! �c`�n�)=br(�b ! �c`�) ! : + : total syst: uncertainty � + : � : . measurement of b-baryon lifetime the analysis followed the method previously used [ ] and was based on the muon sample only. since the extrapolation of the � ight direction to the interaction region was not precise enough to separate secondary from tertiary vertices in the b-baryon decay chain, a unique secondary vertex was reconstructed using the �, the correlated high pt muon and an oppositely charged particle (assumed to be a pion) with momentum greater than . gev/c . the muon and the candidate pion were required to have at least associated hits in the microvertex detector. to reduce the combinatorial background, the (��) invariant mass was required to be less than . gev/c and the (��) invariant mass to be less than . gev/c . furthermore, the contribution of the muon and pion track to the � of the vertex was required to be less than . and the contribution of the � ight path less than . in case of more than one reconstructed vertex, the vertex with the pion of highest momentum was chosen. out of right sign �� events with : < m(p�) < : gev/c , decay vertices were reconstructed. this procedure selected b-baryons in which the subsequent charmed particle in the decay chain had a small decay length with respect to the resolution of secondary vertices. in simulated data this did not introduce any sizeable bias in the decay length distribution of the b-baryon; the e�ciency was %, and in % of the cases the candidate pion associated with the vertex originated from the �b decay chain. the b-baryon purity of the sample after the vertex reconstruction, fs, was determined from the data by a �t to the mass plots for the right and wrong sign correlations (�gures .a,b). assuming an equal number of background events in both samples, the �t gave fs = ( � )%. background events came from fake vertices, whose lifetime distribution had an average value of zero and a gaussian spread determined by the detector resolution, and from sec- ondary vertices originating from charm baryon and b meson decays ( flying background component). the latter component was predicted by the simulation to be ( � )% of the background, both in the right and wrong sign pairs. its average lifetime was deter- mined from the data using a larger sample of candidate decays reconstructed in the high pt muon events, as described in [ ]. the b-baryon momentum was estimated from the total momentum ptot of the decaying particles using the residual energy technique. the residual energy was computed by subtracting the energy associated with the b-baryon candidate (the �, the muon and the pion energy) from the total energy associated with charged particles in the hemisphere containing the � and the lepton, de�ned by the plane perpendicular to ptot. the b- baryon energy was estimated by subtracting this residual energy from the beam energy. the energy associated with all neutral particles in the hemisphere was by de�nition associated with the b-baryon by this method. the charged pions from the b-baryon decay chain may be wrongly included in the residual energy computation. as discussed in [ ], the two e�ects nearly compensate, the correction factor computed in the simulation to reproduce the generated spectrum being on average : for unpolarized b-baryons. sources of systematic error on this factor are the uncertainties on the b-baryon mass and polarization, its momentum spectrum and semi-leptonic decay modes. their e�ect on the �nal lifetime result is listed in table . the resolution of the b-baryon momentum predicted by the simulation was %, as shown in �gure . the e�ect of the non-gaussian tails of the distribution on the �nal result of the lifetime �t was found to be negligible (see below). a maximum likelihood �t was performed simultaneously to the lifetime distribution of the events of the signal sample and to the one of the background vertices described above ( events) with the likelihood function [ ]: l = ��i ln[f(ti;�i;�;�bck)]; with f(ti;�i;�;�bck) = fse (� i = � �ti=�) � erf � �i=� � ti=�i)= p � = � + ( � fs)�� ffbe (� i = � bck �ti=�bck) � erf � �i=�bck � ti=�i)= p � = �bck + fnfe �t i = � i � where � and �bck are the signal and background lifetimes; �i is the error on the measured decay time ti; the normalization constant fs for the signal fraction was �xed to the �tted value of the b-baryon purity discussed above; �nally, ffb was the normalization constant for the background fraction from b;d meson decays and fnf = �ffb is the fraction of \non- ying" background. the three parameter �t to the decays in the ��x channel, gave the result: �(b-baryon)= : + : � : ps with a background lifetime �bck = : + : � : ps and ffb = : � : , in agreement with the simulation. the lifetime distributions for the signal events and for the background, together with the probability functions resulting from the �t, are shown in �gures .c,d. the uncertainties on the magnitude of the ying background and on its lifetime are accounted for in the statistical error of the �t result. the correlation matrix is shown in table , where the small anticorrelation between the signal and background lifetimes is quanti�ed. the di�erent contribution to the systematic uncertainty are listed in table . the �rst comes from the uncertainty on the sample composition, while the others a�ect the estimation of the b-baryon momentum. the assumed value of the average b- baryon mass, mbar, was shifted with respect to the measured mass of the �b, m(�b) = � mev=c [ ], to take into account the contribution to the observed decay channel of the production of �b particle (measured to be times smaller than �b production [ ]), whose mass is expected to be � mev/c higher than the �b mass. the same �tting procedure applied to the monte carlo simulation sample gave: �bck = : + : � : ps and �(b-baryon)= : + : � : ps, compatible with the generated av- erage b-baryon lifetime of . ps . in the simulation, di�erent samples of b-baryons were generated with average lifetimes varying in the range : � : ps and added in turn table : contributions to the systematic error on the average b-baryon lifetime measured using �� correlations. error source variation level syst:error(ps) b�baryon purity : � : � : �c decay mode uncertainty one st:dev: [ ] � : < eb > : � : � : mbar � mev � : �b polarization � : � : � : �(!) = exp[aiw ( � !)] aiw = : + : � : � : br(�b ! �c`�n�)=br(�b ! �c`�) ! : � : total syst:error � + : � : table : correlation matrix between the variables of the lifetime �t. � � �bck ffb � : �bck � : : ffb � : � : : to hadronic z events in which all the other sources of ying background were kept with constant lifetimes. the number of b-baryons in the sample was chosen to reproduce the purity observed in the data. the response of the �tting procedure was linear, without any bias over the whole time interval considered. summing the systematic uncertainties listed in table in quadrature gives an overall systematic uncertainty of + : � : ps , much smaller than the statistical uncertainty from the �t. �c` channel in this section a study of �b semileptonic decays using fully reconstructed �c is pre- sented, based on the data collected in the and . possible sources of �c ( ��c) `� (`+) in the same jet are �b semileptonic decays, b meson semileptonic decays and accidental correlations of a �c and a lepton. the �c` combinations from �b decays are characterized by higher invariant mass and higher transverse and longitudinal momentum of the lepton than the background pairs from accidental correlations. the contribution of the b meson semileptonic decay to a �c was estimated to be negligible, by an argument similar to that used in section . . � c selection the �c was reconstructed via the decay �c ! pk�. this is the most abundant decay mode but it is accompanied by a large combinatorial background. in order to enhance the signal, kinematic selection criteria on the �c candidates were optimized using the simulation. the �c was only accepted if the candidate's momentum was greater than gev/c and if the proton momentum was greater than the � momentum and also greater than gev/c. the protons and kaons were identi�ed by the rich or by requiring that their de=dx measurements be within standard deviations of the expected values. in addition, all three tracks were required to have at least hits in the vd, the � probability of the -prong �tted vertex was required to exceed : and the ight distance in the r� plane, lt, was required to be greater than �m. figure shows the pk� invariant mass distribution obtained. a �t to the pk� invariant mass distribution using a gaussian distribution superimposed on a linear background yields a signal of � events. . � c ` correlations to improve the �c e�ciency in events with an identi�ed lepton, the cut described above on the ight distance of the �c candidate was relaxed, requiring only lt > : the �c candidates were paired with identi�ed leptons with momenta greater than gev/c within a cone of � around the �c direction. the lepton was required to have a pt greater than . gev/c. the total momentum of the lepton and of the �c was required to be greater than gev/c and the invariant mass of the �c � (�c e) pair was required to exceed . gev/c ( . gev/c ). the m(pk�) invariant mass spectrum of �+c (� � c ) candidates associated with a `� (`+) in the same jet is shown in �gure a. a signal of : � : events ( : � : �c� and : � : �ce events) around the nominal �c mass is visible. no peak was found in the pk� mass distribution for �c candidates with a lepton of the same sign in the same jet (�gure b). the signal in �gure a was interpreted as coming from b-baryon! �cl�x decays. the contribution to the right sign sample from accidental combinations of a �c and a lepton and from �c-lepton pairs from b meson decay was estimated to be negligible. no contribution from the �c signal could be attributed to a kinematical re ection of a d + decaying into k�� or a d+s decaying into kk�. the simulation of the decay �b ! �c�� gives an overall e�ciency of selection and reconstruction of ( : � : )% in the decay mode �c ! pk�. if one or more pions are produced in the �b semileptonic decays, the e�ciency becomes ( : � : )% (assuming up to a maximum of % of decay modes with or pions, in equal amounts) due to the softer spectrum of the �c and of the �. this e�ect was included in the systematic uncertainties. using the measured rate br(�c ! pk�) = ( : � : )% [ ], this leads to a production rate: f(b! b-baryon)�br(b-baryon! �c��x) = ( : � : + : � : )%. the overall simulated reconstruction e�ciency of ( : � : )% for the decays �b ! �ce� gives a production rate: f(b! b-baryon)�br(b-baryon! �ce�x) = ( : � : + : � : )%. assuming lepton universality: f(b! b-baryon) � br(b-baryon! �c`�x) = ( : � : + : � : )%. table summarizes the di�erent contributions to the systematic error. table : contributions to the total systematic uncertainty on the b-baryon production rate times the branching ratio to �c`�x. source of uncertainty variation level syst:uncertainty(� ) �b sel: + rec: e�ciency ( : � : )% � : �c branching fraction ( : � : )% � : �b polarization � : � : � : �(!) = exp[aiw ( � !)] aiw = : + : � : � : br(�b ! �c`�n�)=br(�b ! �c`�) ! : + : total syst:uncertainty � + : � : . measurement of b-baryon lifetime in the �c`�x channel, b-baryon candidate vertices were reconstructed using the trajec- tories of the �c and the lepton to �t a common vertex. the �b momentum was estimated with the missing energy technique: e�b = ebeam � evisible + e�c + e` where evisible was the sum of the energies of both charged and neutral particles in the same hemisphere as the �c. the quantity ebeam�evisible measured the neutrino energy in the b-baryon semileptonic decay (this was not true in the �` analysis, where the �c decay was not fully reconstructed), provided that only the -body �c`� decay mode was present. in this case, the simulation showed that the momentum used must be scaled by the factor : � : , where the uncertainty was due to the �nite statistics available. if one or two additional pions were produced in the �b decay, the estimator gave a �b energy that was on average respectively . or gev too low, but this e�ect was reduced by the lower e�ciency of the many-� modes with respect to the -� mode. a sample of signal vertices was selected using right sign �c` pairs with : < m(pk�) < : gev/c . the b-baryon purity of this sample was determined from a �t to the data to be ( � )%. in a similar way, a sample of background vertices was selected with wrong sign pairs with : < m(pk�) < : gev/c and sideband right sign pairs ( : < m(pk�) < : gev/c and : < m(pk�) < : gev/c ). the reconstructed �c track and the lepton were �tted to a common secondary vertex (the b-baryon candidate decay vertex); the proper time distributions of the signal and background samples, shown in �gure c and .d respectively, were �tted with the same technique used for the study of the �` channel. the result is: �(b-baryon)= : + : � : + : � : ps (�c`�x channel, decays). with a ying background lifetime of : + : � : ps; the correlation matrix of the �t parameters is shown in table . the �tted ying background fraction was : � : . the di�erent contributions to the systematic error are shown in table . the e�ects of the �b polarization have been studied with the simulation and found to be negligible. muon-proton channel in the analysis of this channel, semileptonic decays of b-baryons were selected by the presence of a muon and a proton of high momenta and opposite charges in the same jet. about , hadronic events recorded in with the barrel gas rich operational table : correlation matrix between the variables of the lifetime �t in the �c` sample. � �bck ffb � : �bck � : : ffb � : � : : table : contributions to the systematic error on the average b-baryon lifetime measured using �c` correlations. error source variation level syst:error(ps) b�baryon purity : � : � : monte carlo statistics � � : mbar � mev � : br(�b ! �c`�n�)=br(�b ! �c`�) ! : � : total syst:error � + : � : were used. proton selection used the measurement of the speci�c energy loss in the tpc (de=dx) and the detection of cherenkov photons in the rich. the proton is thought to come predominantly from the chain decay b-baryon ! ��c-baryon, c-baryon ! px. it is noted that the ight distance of the secondary charm baryon is, on average, much less than that of its parent, and that the fast proton follows its direction. to allow for a precise determination of the b-baryon decay vertex, which is essential for the present analysis, the proton and muon candidates were required to have at least two associated hits in the vertex detector. detailed simulations showed that % of �b ! ��px decays gave rise to a reconstructed three-dimensional �-p vertex. these vertices were distributed around the simulated �b decay vertex with a precision of � �m in the r� plane. the requirement of the detection of the proton in the vd and secondary muon- proton vertex reconstruction substantially reduced backgrounds due to tertiary protons: only ( � )% of the signal was estimated to be protons from non-charmed hyperon decays in the b-baryon decay chain. this results in an overlap smaller than % between this sample and the �� sample discussed above. . signal and background characteristics the signal muon-proton pairs have the following properties: the muon has hard mo- mentum (p�) and transverse momentum (pt ) spectra, the proton has a hard momentum (pp) spectrum, the muon and proton form a secondary vertex and they have opposite charge. the background is due to genuine protons which do not come from from b-baryon decays and to pions and kaons misidenti�ed as protons, as well as charged hadrons faking muons. the background involving genuine protons was almost completely eliminated by re- quiring the proton momentum to be above . gev/c and the muon momentum above gev/c. the background involving fake protons is dominated by charged kaons. at low pt the muon-kaon pairs are predominantly of opposite charge whereas at high pt the background is mostly same sign pairs. this ip in the charge correlation of the back- ground involving kaons is caused by semileptonic b-hadron decays b ! c�� followed by a c ! sx transition dominating at high pt and semileptonic decays of primary and sec- ondary charm hadrons c ! s�+�� dominating at low pt . because of this, the procedure of removing events below a given transverse momentum of the muon and subtracting the wrong charge correlation, used in the analyses of �` and �c` channels, was not followed. instead, a global �t (see section . ) to the muon pt spectrum, the hadron de=dx distribution and the proper time distribution of reconstructed muon-hadron vertices was applied to the separate samples of muon-hadron pairs enriched in protons, kaons and pions simultaneously. these samples were obtained with the use of the rich as explained in the next section. in this way the yield of b-baryon signal and its average lifetimewas extracted using all charged hadron identi�cation information and minimizing the dependence on the simulation. . sample de�nition . . hadron identi�cation hadronsy were selected in a momentum range where energetic kaons and protons could be separated by the gas radiator of the rich, namely p � : gev/c. in this range, the expected mean number of cherenkov photons detected for a kaon by the rich was greater than . . protons up to gev/c are below the cherenkov threshold. k/p separation was e�ective up to gev/c and covered most of the high momentum part of the spectrum of the signal protons. using the information provided by the rich, four separate samples of energetic charged hadrons were de�ned: � the proton sample. this contained tracks whose proton hypothesis probability ex- ceeded %. this cut suppressed kaons and pions su�ciently to make the p:k:� ratio approximately : : . � the kaon sample. this contained tracks whose kaon hypothesis probability exceeded %. this cut removed all protons and gave a k/� ratio greater than . � the pion sample. this required that the pion hypothesis probability exceeded % and that more than cherenkov photons were compatible with the pion hypothesis. all protons and kaons in this data set were suppressed by this cut. � the unresolved hadron sample taking all tracks not accepted in the previous three samples. the composition of these samples was determined using de=dx measurement from the tpc. in the momentum range above . gev/c pions, kaons and protons are on the relativistic rise of the de=dx. the mean values of their energy loss di�er by approximately constant amounts from � gev/c up to � gev/c. requiring at least hit tpc wires to analyse a track, the ratios de dx =tj(p) of the measured mean energy loss to the momentum dependent theoretical values tj(p) (j = p,k,�) have gaussian distributions with a common precision of � %. the consistency between the theoretical and observed speci�c ionization was checked on the four samples described above. this ensured a very good parameterization of the speci�c ionization measurement, independent of the simulation. . . muon-hadron selection the selection procedure consisted of three sets of cuts, which will be referred to in the determination of the selection e�ciency (section . ): y in what follows hadron stands for a charged particle not identi�ed as a muon. . event and muon selection: in addition to the hadronic event selection described in section a successfully reconstructed primary vertex was required, formed by at least three charged tracks with the � probability of the vertex �t greater then %. the muon candidate selection (section . ) was complemented by the requirement that the muon candidate had at least two associated hits in the vertex detector and a momentum above gev/c. these cuts de�ned the event sample used for the determination of the number of muons from b decay (see section . ) and to which the muon-hadron vertex search was applied. . hadron track quality cuts: hadrons were accepted when the information from the rich was available for the hadron track, when the hadron track had at least two associated hits in the vertex detector, and more than wires used for the de=dx measurement. . muon-hadron vertex de�nition: muon-hadron pairs were accepted when the hadron had a momentum above . gev/c, when the muon and the hadron were in the same jet, when the muon-hadron secondary vertex had a probability greater than %, and the error on the distance �v between the primary and the secondary vertices was smaller than mm. combining these three sets of cuts with the rich selection described in the previous section, four samples of muon-hadron pairs were obtained: the muon-proton sample (�p) and the muon-kaon (�k), muon-pion (��) and muon-unresolved (�x) control samplesz. . b-baryon lifetime . . global fit procedure a maximum likelihood �t was used to estimate the number of muon-proton pairs from b-baryon decays and the average lifetime of b-baryons. for each �-hadron event, the de=dx, the signed muon transverse momentum p (s) t = s � pt (where s = + for the right sign and s = � for the wrong sign correlation), and t = �v =(pbar=mbar), where �v is the distance of the �-hadron vertex from the primary vertex, were considered as a set of three independent measurements. the last quantity estimated the b-baryon proper time assuming the event belongs to the signal. to compute it, the b-baryon momentum pbar was evaluated using a linear relationship with respect to j~p� + ~ppj obtained in the simulation (� � % accuracy at gev/c and � � % at gev/c). six classes of events were distinguished: ( ) the signal, the backgrounds involving ( ) protons, ( ) kaons from b-hadron decays, ( ) other kaons, ( ) pions from b-hadron decays and ( ) other pions. each class had its own probability density function (pdf ) being the product of the three pdf 's associated to each of the measured quantities: p(p(s)t ; dedx ;tjclass) = p?(p (s) t jclass) � pde dx (de dx ;�de dx jclass) � pt(t;�tjclass) the p? probability density functions were taken from the simulation. in this pdf the distinction between di�erent 'kaon' classes ( and ) and 'pion' classes ( and ) were preserved to allow for variations in the muon transverse momentum distributions resulting from the two components of the backgrounds of kaons and pions. z in the following, the notation �i will be used to refer generically to one of these four samples. the pde dx probability density function was taken to be: pde dx (de dx ;�de dx jj) = p ��de dx exp @�( de dx =tj � ) �de dx a where tj were momentumdependent theoretical mean values of the de=dx for the hadron from the class j. the signal pt probability density function was parameterized as a convolution of an exponential decay probability density function of mean ��p and a gaussian resolution function. the kaon and pion background pt probability density functions were taken as linear combinations of a ying part (fraction fbgd(k or �) described by a convolution of an exponential decay of e�ective lifetime �bgd(k or �), and a resolution function) and a 'non ying' part (fraction -fbgd described by a resolution function alone). these four parameters, �bgd(k), �bgd(�), fbgd(k) and fbgd(�), were determined by the �t. for the pt probability density function of the proton background two extreme parameterizations were used: the pion one and a gaussian parameterization. the �nal results were obtained by averaging the results of the �ts performed with these two parameterizations of the proton background pt pdf , taking half of the di�erence as a contribution to the systematic error. the following negative log-likelihood function was minimized by the �t: l = � x �i n�ix n= ln @ x class= f(classj�i)p([p(s)t ; dedx ;t]njclass) ; a where n�i was the population of sample �i and f(classj�i) was the fraction of events in sample �i coming from the given class. the composition parameters f(classj�i) were constrained by four normalization conditions (one for each sample): p j= f(jj�i) = . moreover, the relative contents f(jj�i)=f(j + j�i) of the proton classes (j = ), the kaon classes (j = ) and the pion classes (j = ) were the same in each sample. this left independent fractions to be determined by the �t. the proton content in the three control samples and the kaon content in the �� sample were found by the �t to be compatible with zero and were �xed to zero in the �nal �t, leaving only seven composition parameters to be determined. the systematic e�ect introduced by this assumption was taken into account in the contributions from the background composition. . . results of the fit the �t was performed with events of the �p sample, events of the �k sample, events of the �� sample and events of the �x sample. the projections of the �t space onto the p (s) t , � = ( de dx =tp � )=�de dx and t axes are shown in �gures , , and respectively. the purity of the signal can be read from �gure where additional cuts on p (s) t > : gev/c and � < : were applied to the �p sample. the number of signal events present in the muon-proton sample was estimated to be n(�p from b-baryon) = : + : � : + : � : + : � : : the average lifetime of b-baryons was estimated to be ��p = n : + : � : � : (syst:exp:) � : (syst:theory) o ps : the �rst systematic error was due to the measurement procedure, whereas the second represents the in uence of unknown b-baryon properties. the estimates of the seven composition variables chosen as �t parameters, together with the �ve variables involved in the lifetime part of the likelihood function are reported in table . the correlation matrix for the variable parameters is given in table . the \compo- sition" parameters (p � p ) and the \lifetime" parameters (p � p ) are practically uncorrelated. there was no parameter correlated to the mean b-baryon lifetime (p ) by more than � %. table : the result of the maximum likelihood �t of the average b-baryon lifetime and the composition of the selected samples. the �rst error quoted comes from the �t, the second is half the di�erence between the results corresponding to the two di�erent proton background parameterizations. parameter result p : fraction of signal in the �p sample . + � : : � . p : ratio (signal)/(all p) . � . � . p : ratio (k from b)/(all k) . + � : : � . p : ratio (� from b)/(all �) . + � : : � . p : fraction of kaons in the �p sample . + � : : � . p : fraction of kaons in the �k sample . + � : : � . p : fraction of kaons in the �x sample . + � : : � . p : average lifetime of b-baryon��p . + � : : � . ps p : �bgd(k) . + � : : � . ps p : �bgd(�) . + � : : � . ps p : fbgd(k) . � . � . p : fbgd(�) . + � : : � . . . fit systematics the parameters p and p describe the relative amount of true kaons and pions arising from b-hadron decays among all kaons and pions. to examine relevant systematic e�ects, three approaches were taken: ( ) three di�erent de�nitions of these parameters were used (a) k (�) from b all k (�) , (b) k (�) and � from b all k (�) , (c) k (�) and direct � from b all k (�) ; ( ) these fractions were �xed to the monte-carlo prediction; ( ) �k or �x samples were excluded from the �t. the maximal variation of the �t results was taken as a contribution (\k, � bkg composition" in table ). to evaluate possible systematics related to the parameterization of the p? probability density function of the proton background class, this class was divided into four groups characterized by very di�erent p (s) t spectra of the accompanying muon: ( a) right sign muons from b-hadron decays, ( b) wrong sign muons from b-hadron decays, ( a) other right sign muon candidates ( b) other wrong sign muon candidates. from the set of these four groups, non-trivial subsets can be chosen ( containing one group, containing two groups and containing three groups). the �t was performed times with the p? probability density function of the proton background sample determined after the chosen subset was scaled up by a factor of . the maximal variation was taken as an estimate of the systematic e�ects (\p bkg composition" in table ). the results quoted were obtained with pt calculated including the muon candidate in the jet. to evaluate systematic errors, pt was replaced ( ) by pt out calculated excluding table : correlation matrix for the �t parameters. the de�nitions of the parameters are given in table . p . p . . p -. -. -. p -. . . . p -. -. -. . . p -. -. -. . . . p -. . . . . -. -. p . -. -. -. -. . . -. p . . -. -. . . . -. -. p -. -. -. -. . -. . -. -. . p -. . . . . . -. -. . -. -. p the muon candidate from the jet and ( ) by the quadratic sum q (pt + (p�= ) ). all three de�nitions were tested with several binnings. the maximal variation was taken as a contribution to the systematic error (\pt binning/de�nition" in table ). in the likelihood function, the pt probability density function was used only for the right sign muon-proton sample, and optionally for the part above some pt cut. outside this sample pt pdf's were �xed to a constant value for all classes. the result was found to be stable within % in the range of pt cut from gev/c (no cut) to . gev/cas can be seen in the �gure . for higher cut values, the b-baryon lifetime begins to uctuate within increasing statistical error. the �t procedure was tested in the following way. from the available statistics of signal muon-proton pairs in simulated b-baryon decays passing all the selection cuts, di�erent sets of pairs each were randomly chosen; from each of them a larger test sample of muon-hadron pairs was formed by adding a number of muon-unresolved hadron pairs randomly chosen from real data, in such a way as to reproduce in the test sample the signal fraction . observed in the data. the generated lifetime of the b-baryon in the simulation was . ps. the whole �t was repeated several times with the data muon- proton sample replaced by one of the test samples described above. the distributions of the �t result for the proton signal fraction p and for the average b-baryon lifetime p are shown in �gures a,b respectively; their average values reproduced the known input values of the parameters, with a spread in agreement with the average �t error. . branching ratio the number of signal events found by the �t was used for the calculation of the following production rate: f(b ! b-baryon) � br(b-baryon ! p��x) = ( : � : � : + : � : )%. the �rst systematic error is due to the measurement procedure, whereas the second represents the in uence of unknown b-baryon properties. systematic e�ects are sumarized in table . the total experimental systematic error results from the following sources listed in the table: � n(�p from b-baryon) is the number of signal events found in the previous section. table : systematic uncertainties in the �t. source of variation variation level resulting variation of n(�p from b-baryon) ��p [events] [ps] experimental systematics de=dx normalization one stand. dev. � : � : pt binning/de�nition see text + : � : � : k, � bkg composition see text � : � : p bkg composition see text + : � : � : p background pt pdf see text � : � : boost estimate one stand. dev. | � : total systematic error (measurement) + : � : � : systematic uncertainty due to unknown b-baryon properties b-baryon polarization � : � : � : � : �b ! �c�� decay form factor �(!) = exp[aiw ( � !)] aiw = : + : � : � : � : he(b-baryon)i=e(beam) : � : � : � : br(�b ! �c`��)=br(�b ! `��x) : ! : + . + . total systematic uncertainty (theory) + : � : � : table : contributions to the total systematic uncertainty of the b-baryon production rate times its branching ratio into p�x. (for de�nitions of the e�ciencies � , � , � , �r and the correction c� see text.) quantity value contribution � experimental systematics n(�p from b-baryon) . + : � : (syst.) + : � : � . � : � : � . � : � : � . � : � : �r . � : + : total systematic uncertainty (measurement) � : systematic uncertainty due to unknown b-baryon properties c� . � : � : b-baryon polarization � : � : � : �b ! �c�� decay form factor �(!) = exp[aiw ( � !)] aiw = : + : � : + : � : he(b-baryon)i=e(beam) . � : � : br(�b ! �c`��)=br(�b ! `��x) : ! : + : total systematic uncertainty (theory) + : � : � � is the e�ciency of the \event and muon" selection (the �rst item in the section . . ). � � is the e�ciency of the hadron track quality cuts (the second item in the section . . ). this e�ciency was found in the data. � � is the e�ciency of the additional selection de�ned in the third item of the section . . . this e�ciency was found using simulation. � �r is the e�ciency of the selection of the �p sample with the rich. this e�ciency was found by the �t (before �xing to zero proton contents in the control samples). entries for the theoretical systematics are similar to those described in the analysis of the �` channel. c� is the correction due to the residual presence of protons from the chain decay b-baryon! c-baryon!hyperon!proton. conclusions the production and lifetime of the b-baryon has been studied with three di�erent and complementary methods, relying on the detection of a fast �, a �c and a fast proton in the same jet as a high pt lepton. the following semi-exclusive branching ratios have been measured: f(b ! b-baryon) � br(b-baryon ! �`��`x) = ( : � : � : )%, f(b ! b-baryon) � br(b-baryon ! �c`��`x) = ( : � : + : � : )%, f(b ! b-baryon) � br(b-baryon ! p��x) = ( : � : + : � : )%. from partially reconstructed b-baryon decay candidates in these three di�erent semi- leptonic channels, the following values for the average b-baryon lifetime have been mea- sured: �(b-baryon) = : + : � : + : � : ps ( decays, ��x channel), �(b-baryon) = : + : � : + : � : ps ( decays, �c`��x channel), �(b-baryon) = : + : � : � : ps ( decays, p��x channel). the above lifetime determinations rely on completely independent event samples. this was checked on an event by event basis for the �-proton and �-�c samples, where a small overlap could not be excluded a priori by the selection criteria discussed above. the overlap between the � � � and the �-proton samples was found negligible by the simulation, as discussed in section . the common systematics, due to the modelling of the b-baryon production and decay properties, can be inferred from tables , and . averaging the three results, under the assumption that the di�erent b-baryon species enter in the same proportion in the decay channels considered (all of them are expected in fact to be largely dominated by the �b baryon), gives the mean b-baryon lifetime: �(b-baryon) = : + : � : � : (exp:syst:)+: �: (th:syst:) ps. acknowledgements we are greatly indebted to our technical collaborators and to the funding agencies for their support in building and operating the delphi detector, and to the members of the cern-sl division for the excellent performance of the lep collider. references [ ] ua collaboration, c. albajar et al., phys. lett. b ( ) . [ ] aleph collaboration, d. decamp et al., phys. lett. b ( ) . opal collaboration, p. d. acton et al., phys. lett. b ( ) . [ ] delphi collaboration, p. abreu et al., phys. lett. b ( ) . [ ] aleph collaboration, d. buskulic et al., phys. lett. b ( ) ; opal collaboration, r. akers et al., phys. lett. b ( ) . [ ] i.i. bigi and n.g. uraltsev, phys. lett. b ( ) ; g. altarelli and s. petrarca, phys. lett. b ( ) . [ ] delphi collaboration, p. aarnio et al., nucl. instr. meth. a ( ) . [ ] e.g. anassontzis et al., nucl. instr. meth. a ( ) . [ ] delphi collaboration, p. abreu et al., nucl. phys. b ( ) . [ ] c. kreuter, ph.d thesis, karlsruhe university, iekp-ka/ - . [ ] w. adam et al., \analysis techniques for the delphi rich", contributed paper gls , to the th international conference on high energy physics, glasgow . [ ] t. sjostrand et al., comput.phys.commun. ( ) ; ( ) . [ ] the particle data group, phys. rev. d ( ) . [ ] cleo collab., g. crawford et al., phys. rev. d ( ) . [ ] t. sj�ostrand, comp. phys. comm. ( ) . [ ] n. isgur and m.b. wise, phys. lett. b ( ), ; n. isgur and m.b. wise, phys. lett. b ( ), . [ ] delphi collaboration, \production of strange b-baryons decaying into �� `� pairs at lep", cern-ppe/ { , to be published in zeit. f. phys. c. figure : a) p�� invariant mass distribution for � candidates with p > gev=c; the curve is the result of a �t using a breit-wigner function, which takes into account the variation of the mass resolution with the momentum of the decaying tracks, and a polynomial background. b) background subtracted � momentum spectrum (dots: data; histogram: monte carlo simulation) ; c) � ! p�� reconstruction e�ciency computed in the simula- tion. figure : distribution of p� invariant mass for �candidates correlated to high pt leptons in the same jet: a) right-sign pairs; b) wrong-sign pairs. the data are shown by the points; the simulation, normalised to the total number of hadronic z decays, as a histogram: the contribution from b-baryon decay is shown double-hatched, while the background from fragmentation �'s is shown single-hatched. the curves show the result of the �t described in the text. figure : subtracted spectrum (right sign - wrong sign) in the data (dots) for: a) � momentum, b) lepton transverse momentum, c) the sum of the � and lepton mo- menta and d) �` invariant mass. the histograms show the simulation for the b-baryon signal. figure : � signal for reconstructed �� vertices of a) right sign and b) wrong sign respectively; c) lifetimedistribution for b-baryon candidates (hatched area in the �mass plot); the full lines represent the result of the �t described in the text; the dotted-dashed line is the estimated b-baryon contribution, the dashed and dotted lines represent the ying and not- ying background respectively, determined from d) the lifetimedistribution of the background sample, �� vertices with wrong sign or p� mass outside the above range. figure : ratio between estimated and generated �b momentum predicted by the simu- lation for the decay channel �b ! �c��. the curve is the result of a gaussian �t to the distribution. figure : �c inclusive signal for reconstructed pk� vertices. the curve is the result of a �t to the distribution using a gaussian superimposed on a linear background. figure : a,b) pk� invariant mass distribution for �c` pairs of opposite sign and same sign respectively; c,d) proper time distributions for b-baryon signal and background sample. the curves are as in �gure . figure : projection of the data distribution onto the p (s) t axis (where p (s) t is signed transverse mo- mentum of the muon. its positive values corre- spond to the right sign combination (muon and hadron have opposite charges), whereas negative values to the wrong sign one (same sign �{hadron pairs). points with error bars (data) are com- pared to the �t (uppermost curve) decomposed into six classes shown with di�erent hatching. the four plots shown correspond to the four sam- ples used in the �t. figure : projection of the data distribution onto the � axis. points with error bars (data) are compared to the �t represented by the uppermost curve. this curve is the sum of the p, k, � contributions, shown with gaussians centered at � = : ; : ; : respectively. the four plots correspond to the four samples used in the �t: a) �p sample (the signal content is hatched); b) �k sample; c) �� sample; d) �x sample. figure : projection of the data distribution onto the proper time axis for p (s) t > : gev/c. the data are represented by points with the error bars, the �t is shown with up-most continuous lines: a) �p sample { the signal is shown double hatched; b) �k sample { the kaon content is shown single hatched; c) �� sample; d) �x { the kaon content is shown single hatched. figure : projections of the �p sample onto (a) p (s) t axis with a cut � < : , (b) � axis with a cut p (s) t > : gev/c and (c) proper time axis with both cuts applied. the signal content is shown double hatched (the hatching on the �gure (a) is explained in the caption to the �gure ). muon transverse momentum cut (gev/c) b -b a ry o n l if e ti m e ( p s ) . . . . . . . . figure : study of the stability of the b-baryon lifetime determination with respect to a given muon transverse momentum cut. the width of the double hatched area shows the uncertainty due to parameterization of the proton background pt e�ective lifetime (the lower border was obtained with the pion parameterization, the uper one with zero e�ective lifetime). vertical bars shows the symmetric error of the �t. figure : results of the toy monte carlo simulation described in the text { points with error bars { are �tted with gaussians for a) estimated signal yield (input value = , output mean value = , rms = ); b) estimated b-baryon lifetime (input value = . ps, output mean value = . ps, rms = . ps). things of beauty nature physics | vol | march | www.nature.com/naturephysics editorial what is the most beautiful concept in physics? answers to that question will be many and diverse — depending on whom you ask, their background and ‘soft spots’, on their teachers, and on personal ‘light bulb’ moments. there are ideas in physics that strike us as simply beautiful from the first moment we encounter them: their full implications and significance still far from apparent, they seem to have an innate and inevitable elegance. for many, and certainly for those who have a weakness for quantum mechanics, the aharonov–bohm effect is among those ‘beautiful things’. the very idea is intriguing: that a solenoid can have a measurable effect on a charged particle even if the particle never passes through a region where either the solenoid’s electric or magnetic fields are non-zero. but the implications are of course much broader. last year marked years since its discovery. writing on page of this issue, murray peshkin and lev vaidman survey an “intellectually delicious” meeting that took place, in december , at the birthplace of the effect, the h. h. wills physics laboratory in bristol. the event celebrated the fiftieth anniversary of the discovery of the aharonov–bohm effect, and also years since the discovery of berry’s phase, another (and not unrelated) concept that, for all its many ramifications, also charms physicists with its inherent beauty. on page , sir michael berry recollects the events surrounding his famous paper, discussing both the work that followed shortly after and the anticipations of the geometric phase that preceded his own. “in retrospect what we call ‘discovery’ sometimes looks more like emergence into the air from subterranean intellectual currents”, says sir michael. there is much more still to emerge from the -year-old aharonov–bohm effect, which may well have impact on the very foundations of quantum physics. indeed, on page sandu popescu argues that the deepest implication of the effect has been widely ignored so far — and that, without it, a real understanding of the nature of quantum mechanics is impossible. when john keats wrote his poem endymion it wasn’t physics he had in mind, but his famous opening line rings true in this case too: “a thing of beauty is a joy for ever”. ❐ the celebration of years of the aharonov–bohm effect, and years of berry’s phase, is a celebration of the elegance of physics. things of beauty funding of the arxiv preprint server must now be shared by more of its users. treasured archive the arxiv preprint server has become central to the working lives of most physicists: ‘checking the arxiv’ is the starting point of many a daily routine. founded by paul ginsparg, the arxiv has expanded to include not only physics — astrophysics, condensed matter, and high- energy physics being heavily represented — but also mathematics, computer science, quantitative biology and even quantitative finance. the arxiv now hosts nearly , preprints from , registered submitters in countries, and serves more than . million article downloads every month to , users. the statistics are remarkable. and it is also remarkable that, having initially been hosted at the los alamos national laboratory, the server has in recent years been funded and managed by a single institute, cornell university. now the operating costs of the ever-growing arxiv match the entire cornell library budget for physics and astronomy, and the university has made a plea for help in funding it. as a short-term solution, cornell is approaching the top user-institutions of the arxiv — who account for % of institutional downloads — for a financial contribution to the maintenance of the arxiv. it is heartening that help has already been promised from several large universities and laboratories, but wider support is still being sought. for the longer term, cornell will assess, with those who come forward to support the arxiv, what the options are in developing a sustainable model for the future. secure, ongoing funding of the preprint server is vital, and surely deserves at least national endorsement from us funding bodies, if not some international arrangement. the fast communication of results — data or theory — between experts that the arxiv facilitates is a boon to physics, and one well recognized by the nature publishing group: any submission to nature physics or its sister journals may be posted, in that original submitted form, on the preprint server (although we do ask that the final, revised and accepted version is not posted until six months after publication in the journal; the published version, in the nature physics layout, may not be posted). it’s up to physicists now to sustain their arxiv, encouraging their institutions’ libraries in particular to engage in its development. more information is available at http://arxiv.org/help/support; and comments and suggestions may be sent to support@arxiv.org. ❐ m . b er ry © macmillan publishers limited. all rights reserved http://arxiv.org/help/support support@arxiv.org things of beauty british medical journal january publications: most proposals are based on the ideal district with a single district general hospital. elsewhere it acknowledges that most people do not work in such a setting and that the biggest problems are in the conurbations, where all too often social disadvantage is associated with a confused health service for children. the report emphasises that it is time to recognise that in cities and large conurbations the district general hospital concept is often inappropriate or harmful to children's services. the only way to achieve a safe standard of care for children is by the aggregation of children and the concentration of skilled staff and expensive resources where they can be most economically used. this may mean one hospital having no child inpatients or all the child casualties going to one designated accident emergency unit rather than the two others in that city. it is in our cities that the greatest wisdom and skill will be needed in creating the sort of services our children and our future require. ' committee on child health services (chairman, professor s d m court), fit for the future. volumes and , price £ . london, hmso, . british medical ournal, , , . grief and stillbirth stillbirth is a tragedy for the mother and her immediate family, but it also affects the attendants deeply. when the death is diagnosed before birth the latter are anxious whether to tell the mother as well as the father. brave attempts are made to bolster up her courage and fortitude during labour. more drugs may be offered in the hope that they will allay the distress, while forceps delivery and episiotomy seem empty, adding only to continuing distress and pain. a dull, sad quietness pervades the labour ward as the baby emerges, and its floppy body is hurriedly wrapped in a sheet and whisked away. there is no joy; only a sense of complete and utter failure. it is little different when the stillbirth is unexpected, except for the frantic efforts in resuscitation as the silence becomes increasingly oppressive, raising everyone's anxiety, especially the mother's. and again the baby is usually hurried away. telling the mother and the father is a horrid task, and however sympathetically done there is a feeling of incompe- tence in relieving the distress and helplessness in the face of heartbreak. the essential motivation of medicine is to relieve suffering, and here is a denial of that possibility. the response of all is usually to withdraw and not communicate, the well- known phenomenon of rejection. the various attendants may discuss the reasons for the stillbirth and rehearse what went wrong, partly as a means of reducing their own tensions. but often the persons most affected emotionally are unwittingly ignored and left to their own devices. recently, however, there has been growing recognition of the importance of acting out grief and the support of the survivors when there is a death in the family. methods of helping have been identified and recommended,' but so far there has been relative neglect ofthe grief induced by stillbirth. bourne confirmed the tendency of general practitioners to forget the details of stillbirths as compared with their remem- brance of live births. moreover, there was some evidence of mothers being dissatisfied with the help they received, in that many of them transferred to other doctors. another under- standable finding was that more of the mothers who had had a stillbirth became pregnant again quite quickly, and they attended antenatal clinics earlier in the pregnancy than other multiparae. other papers dealing with emotional reactions to stillbirth have emphasised numerically what seems to be predictable to informed insight. - of course, there is much variability in the responses of the bereaved. not all of them start another baby; some return to former jobs, and others fling themselves into a wide variety of time-consuming tasks. the part played by the husband in shaping these decisions is not really known. in general, for emotional reasons medical attendants have not faced this issue rationally and have not worked out a policy for helping those bereaved by stillbirth. lewis has recently pointed out that there is not a person to grieve over, only a potential person. in this there is analogy with the grief of some young widows who mourn the loss of the future with their husbands rather than the past. lewis argues that the parents should be given something tangible to remember and so should touch and see the dead baby, and moreover that they should help with certification and arrange for a proper funeral or cremation, which they and the other children of the marriage might attend. there might well be a marked grave rather than the unfeeling oblivion of a common one. it is "necessary to help the parents to create memories, to bring the baby back to death in their mind." kubler ross' has delineated some of the common patterns of grief, and understanding of these helps with their alleviation. they are no less important in stillbirth than in deaths at a later age. ' dhss, care of the dying. reports on health and social subjects no . london, hmso, . bourne, s, j ournal of the royal college of general practitioners, , , . illsley, r, in childbearing-its social and psychological aspects, eds s a richardson and a f guttmacher. baltimore, williams and wilkins, . newton, n, and newton, m,j ournal of the american medical association, , , . wolff, j r, nielson, p e, and schiller, p, american j ournal of obstetrics and gynecology, , , . giles, p f h, australian and new zealand j'ournal of obstetrics and gynaecology, , , . jensen, j s, and zahourek, r, rocky mountain medical_journal, , , ( ), . lewis, e, in psychosomatic medicine in obstetrics and gynaecology, rd international congress, london . ed n morris. basel, karger, . lewis, e, lancet, , , . '' kubler-ross, e, on death and dying. london, tavistock, . beauty spot or blemish? such is the human condition that everyone has at least one distinguishing birthmark; so it is just as well there are few medical indications for treatment. developmental anomalies arise from the limited number of elements in the skin, and the various lesions can usually be identified by the trained eye, making it possible to give the patient a fairly accurate diagnosis and prognosis. the cause of most birthmarks is conjectural. a few are genetically determined-mongolian spots,-ashleaf leukoderma in epiloia, lentigines in peutz-jeghers syndrome- but the great majority are presumed to be a result of simple mismanagement by the tissue organisers. clearly the genetic constitution of a population may determine the incidence of birthmarks. this is supported by the few clinical studies of birthmarks in neonates, which not surprisingly show a greater frequency of pigmented anomalies o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j: first p u b lish e d a s . /b m j. . . -a o n ja n u a ry . d o w n lo a d e d fro m http://www.bmj.com/ british medical journal january (including melanocytic naevi, lentigo, and mongolian spots) in the more pigmented races. in a recent study of neonates only % had proved pigmented naevi- - lentigo and over % melanocytic naevi-and, since these "birthmarks" are universal, most naevi must in fact develop later in life. indeed, pigmented naevi do grow and multiply during child- hood, adolescence, pregnancy, and the climacteric. the risk of malignant change is negligible except in the rare giant pig- mented naevus, which is always present at birth, and which merits prophylactic surgery. nature does sometimes destroy a naevus spontaneously in a remarkable immune phenomenon known as sutton's naevus-leukoderma acquisitum centrifu- gum-when a white halo appears around a naevus and engulfs it. otherwise treatment may be prompted by cosmetic considerations precipitated by an increase in size, or the patient may become anxious about her naevus, especially if it begins to grow hairs. curettage, cautery, or shaving flush with the skin are reasonable alternatives, but the preferred treatment is by excision-though the insult of a surgical scar must always be weighed against the cosmetic offence of nature's blemish. the common vascular naevi are of three types. firstly, salmon patches may be found in over of neonates.' fortunately those on the face are evanescent, but those on the scalp may persist into adult life. secondly, strawberry marks -capillary vessel tumours-develop in over % of babies; few are detectable at birth, though some may be apparent as telangiectatic areas surrounded by a pale halo. the typical tumour is obvious by six weeks, and it then takes up to a year to reach its maximum size. involution is spontaneous, sometimes starting in the first year of life, but it is slow, and the mark may take several years to resolve completely. never- theless, nearly all have involuted fully by puberty. when marks are exposed to maceration by the napkin ulceration may be a problem; treatment may be needed with topical antibiotics and protective dressings. injury may cause bleeding, but pressure will control it. in large or multiple lesions sequestration of platelets may result in haemorrhage (the kasabach-merritt syndrome), which is best treated by systemic steroids; a daily dose of to mg prednisone according to infant weight is needed for three weeks. this same treatment may be necessary should a strawberry mark interfere with feeding or the development of a vital organ such as the eye. surgery has little to offer in treating strawberry marks, except that plastic revision may be required to deal with redundant skin from the involution of large lesions. radio- therapy does hasten involution, but it is no longer considered good practice because the resultant scar is more unsightly than that arising from natural involution, and it may prejudice the natural growth of underlying and adjacent tissues. in general, a policy of firm reassurance and non-interference is to be preferred. thirdly, the port-wine stain (found in less than . % ofthe population') is invariably present at birth. it follows a dermatome pattern and darkens slowly during life to assume its titular colour. since no treatment is of any avail patients may need to use the excellent cosmetic cover preparations available. sometimes stains may be surface markers of under- lying vascular anomalies, as in the sturge-weber syndrome, where there is an associated intracranial lesion. when found on a limb a port-wine stain may be associated with haemangiec- tatic hypertrophy and arteriovenous communication. other naevi are uncommon. the naevus sebaceus of jadassohn is present at birth as a fawn bald patch on the scalp; it becomes warty and darker with age, but in up to of cases a neoplastic tumour develops in middle life, so prophylactic surgery may be wise when the patient is old enough. epidermal naevi start as yellow streaks; they also become warty and darker, but they are benign; they may be quite extensive, and, since they follow a dermatome distribution, surgery may be difficult. jacobs, a h, and walton, r g, pediatrics, , , . pratt, a g, archives of dermatology and syphilology, , , . walton, r g, jacobs, a h, and cox, a j, british journal of dermatology, , , . reed, w b, et al, archives of dermatology, , , . ster, j, and nielsen, a, acta paediatrica scandinavica, , , . hidano, a, and nakajima, s, british journal of dermatology, , , . fost, n c, and esterly, n b, journal of pediatrics, , , . mehregan, a h, and pinkus, h, archives of dermatology, , , . less usual forms of epilepsy kinnear wilson' said that a faint, a cry, or a laugh could be a fit and that no rigid semilogical framework could embrace all epileptic phenomena. yet years later neurologists are still fascinated by a wish to classify and categorise the multifarious fragments of an epileptic attack, which may be facets of a complex seizure or provide a patient's only presenting symp- tom. epilepsy may be triggered by external stimuli ; and, whereas there are accepted interpretations of the commoner components of temporal lobe abnormalities, the less usual manifestations of epilepsy continue to intrigue and baffle. recently, sethi and surya rao have published a finely written account ofa patient with epileptic laughing, crying, and running in whom they found a well-circumscribed tumour of the left temporal lobe. in a complementary report offen et al described a patient in whom temporal lobe atrophy was associated with paroxysmal attacks of weeping, facial contortion, head turning, and amnesia. the location of laughing (gelastic), crying (quiritarian or dacrocystic), and running (cursive) epilepsy in the temporal lobe is supported by the common concurrence of other clinical phenomena. amnesia for the event is usual. head turning has been reported in four out of six cases of crying epilepsy, and the presence of epigastric auras points to the temporal lobe juxtaposition of visceral, expressive, and affective functions. many studies have provided evidence of temporal and frontotemporal electroencephalographic foci, but the eeg patterns are not stereotyped: gumpert et al, for example, found reduced electrical activity during the periods of laughter. the term gelastic epilepsy (gelos =mirth) includes both a subjective experience of merriment (dostoievsky described seizures of pleasure and harmony ) and complex co-ordinate movements with grinning, giggling, or joyful weeping. patients usually experience a change in mood in parallel with its involuntary external expression: so that the internal states of pleasure or happiness, fear or terror, may respectively be exteriorised as smiling or laughter, crying or sobbing, attempt at flight or fight. although the temporal lobe is most frequently inculpated in emotional epilepsy, grey matter elsewhere may be affected, and one cannot always analyse the nature of the episode. roger et al, reviewing accounts of epileptic attacks accompanied by laughter or smiling found that where these were accom- panied by eeg foci, temporal or occasionally sylvian, further analysis was usually possible; but in over half the cases the laughter or smiling had accompanied petit mal and it was impossible to gauge the affective content of the attack. two o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j: first p u b lish e d a s . /b m j. . . -a o n ja n u a ry . d o w n lo a d e d fro m http://www.bmj.com/ judgment and decision making, vol. , no. , july , pp. – the beauty of simple models: themes in recognition heuristic research daniel g. goldstein∗ gerd gigerenzer† abstract the advantage of models that do not use flexible parameters is that one can precisely show to what degree they predict behavior, and in what situations. in three issues of this journal, the recognition heuristic has been examined carefully from many points of view. we comment here on four themes, the use of optimization models to understand the rationality of heuristics, the generalization of the recognition input beyond a binary judgment, new conditions for less-is-more effects, and the importance of specifying boundary conditions for cognitive heuristics. keywords: recognition heuristic, less-is-more, memory, model comparison. introduction galileo formalized the movement of objects in his law of falling bodies, s. s. stevens ( ) described sensation as stimulus intensity raised to a power, and the behaviorists (e.g., hull, ) formulated laws of learning with equa- tions no more complex than those encountered in high school physics. simple models, from physics to psychol- ogy, have driven much of progress in science. yet no model, simple or complex, can explain all behavior. the beauty of simple models is that one can easily discover their limits, that is, their boundary conditions, which in turn fosters clarity and progress. the law of falling bodies does not hold generally; it works for situations in which the object starts in rest, there is no air resistance, and the gravitational force g does not change over the distance of the fall. similarly, the laws of learning do not hold in every situation, as illustrated by the concept of “biologi- cal preparedness”: the fact that certain cs–ucs (condi- tional stimulus – unconditional stimulus) associations are learned rapidly but not others (garcia, ervin, & koelling, ). evolved organisms work with multiple tools, not one general principle. the concept of an adaptive tool- box assumes that an individual, culture, or species can be characterized by a set of heuristics for surviving in an uncertain world. these heuristics exploit evolved and learned core capacities, and are simple in order to be ro- bust, fast, and efficient. the recognition heuristic is one of these tools in the adaptive toolbox of humans (and other animal species) and exploits recognition memory. this journal has devoted three special issues to elaborat- ∗yahoo research and london business school, w. th street, new york, ny . email: dan@dangoldstein.com †max planck institute for human development a person jumping headfirst from an airplane will never exceed a speed of about km/h ( mph), due to air resistance. ing, generalizing, and testing the model we proposed a decade ago (goldstein & gigerenzer , ). we have reviewed the progress made in the first decade be- fore (gigerenzer & goldstein, ); here we would like to comment on some of the theoretical insights put for- ward by the contributions to these issues. . use optimization models to under- stand heuristics one of the central questions in the research on the adap- tive toolbox is, “how can a decision maker know in which situation a given heuristic is efficient?” one methodolog- ical approach to answer this question is to choose an op- timization model whose structure is well understood and try to map the building blocks of a heuristics into this structure. signal detection theory is such an optimization model that has been used to understand the nature of fast- and-frugal trees (luan, schooler, & gigerenzer, ) and the effect of false alarms and misses on the recogni- tion heuristic (pleskac, ). davis-stober, dana, and budescu ( ) mapped the recognition heuristic into a different class of optimization models, the framework of linear models. they compared its weighting scheme (place all weight on one predictor, recognition, and none on the rest) to multiple regression’s scheme on the dimen- sion of minimizing maximal risk. (a weighting scheme minimizes maximal risk when it is, on average, closest to an optimal set of weights.) the recognition heuris- tic can be shown under plausibly common conditions to approximate a mini-max weighting scheme which is op- timal on this prevalent criterion. while decision makers do not have access to the correlations that would let them assess whether “overweighting” recognition is a promis- ing weighting strategy in a given domain and thus can- judgment and decision making, vol. , no. , july benefits of simple models not be said to be optimizing from the information given, users of the recognition heuristic are effectively betting that the environment will have the structure that davis- stober, dana, and budescu describe. when these bets are correct, inferences will be close to optimal despite having arisen without learning cue values or weighing multiple sources of information. an appealing future direction for this work would be to manipulate the costs to the decision maker of erring on the basis of risk, as opposed to other statistical benchmarks, and to observe whether such in- centives cause decision strategies to fall more or less in line with the predictions of the recognition heuristic and minimax weighting. . beyond binary recognition whereas the davis-stober, dana, and budescu paper connects the recognition heuristic to broader analytical results on cue weighting, the erdfelder, küpper-tetzel, and mattern ( ) article connects definitions within the recognition heuristic model to theories of recognition memory, meeting the call of other memory researchers in the field (tomlinson, marewski, & dougherty, ; dougherty, franco-watkins, & thomas, ). recall that the recognition heuristic takes the output of recogni- tion memory as its input, but does not provide a model of the underlying recognition memory process (goldstein & gigerenzer, ). erdfelder et al.’s memory state heuris- tic (msh) builds upon the recognition heuristic as well as the two-high threshold model of recognition (bröder & schütz, ; snodgrass & corwin, ), positing three natural states of memory—recognition certainty, memory uncertainty, and rejection certainty—rather than the two in our original model (goldstein & gigerenzer, ). the msh model subsumes the recognition heuris- tic as a special case and nicely resolves a number of ob- served phenomena. these include ( ) the negative cor- relation between adherence and recognition latency (e.g., marewski & schooler, ; hertwig, herzog, schooler, & reimer, ; newell & fernandez, ), ( ) the dif- ference in accordance for pairs in which the recognition heuristic is normatively correct or incorrect (e.g., hilbig & pohl, ), and ( ) the difference in accordance on pairs in which the recognized object is merely recognized or associated with further knowledge (e.g., marewski & schooler, ; marewski, gaissmaier, schooler, gold- stein, & gigerenzer, ; hilbig & pohl, ; hilbig, pohl, & bröder, ). extending the number of recog- nition states from two to three is a sufficient condition for these phenomena. these results show, for instance, that it is not valid to conclude that accordance differences be- tween normatively correct and incorrect pairs would im- ply the use of additional cue information besides recogni- tion, as has been claimed before. for instance, glöckner and bröder ( ) conclude that measuring such a differ- ence (the "discrimination index") is "a very clever way to prove the use of additional cue information" (p. ). the general methodological lesson is: if a subset of participants does not follow the predictions of the recog- nition heuristic, this does not imply that this subset uses a compensatory strategy. yet all three phenomena above have been repeatedly interpreted as evidence for compen- satory strategies. if erdfelder et al.’s generalization of the recognition heuristic applies, the conclusion is that there may be a subset of participants who distinguish between three recognition states and apply the generalized recog- nition heuristic to these. . conditions for less-is-more in , we showed that less-is-more effects can result both from the recognition heuristic (figure , gigeren- zer & goldstein, ) as well as from compensatory processing of recognition, such as tallying and regres- sion (figure , gigerenzer & goldstein, ). that is, observing a less-is-more effect does not imply that the recognition heuristic was used. the logic goes the other way around: if certain conditions hold (α > β; α, β inde- pendent of n; goldstein & gigerenzer, ), this implies an inversely u-shaped function between accuracy and n, that is, a less-is-more effect. beaman, smith, frosch, & mccloy ( ) extend this argument and investigate the conditions behind less-is-more effects beyond the recog- nition heuristic. katsikopoulos ( ) provides new in- sights into how less-is-more effects depend on false alarm rates and miss rates, and derives conditions for a below- chance less-is-more effect. smithson ( ) provides fur- ther conditions for less-is-more effects. taken together, these three papers show a number of conditions that lead to less-is-more effects that were previously unknown. the challenge is to integrate these into a common the- oretical framework. . boundary conditions in the introduction, we mentioned the importance of specifying the boundary conditions of a strategy, heuris- tic or otherwise. figure (from gigerenzer & goldstein, ) illustrates one boundary condition: the recogni- tion heuristic, like take-the-best, was formulated for in- ferences from memory, as opposed to inferences from givens (gigerenzer & goldstein, ). if an object is not recognized (object d in figure ), no cue values can be recalled from memory (these missing values are rep- resented with question marks). in contrast, in inferences from givens—such as when one looks up the cue val- ues of recognized and unrecognized products online— this restriction does not hold. in inferences from mem- judgment and decision making, vol. , no. , july benefits of simple models figure : recognition states of four objects a through d. cue values are positive (“−”), negative (“−”), or missing (“?”). when an object such as d is unrecognized, all cue values are unknown. adapted from gigerenzer & goldstein, , p. . objects: a b c d recognition + + + − cues: cue + − ? ? cue ? + − ? cue − + ? ? cue ? − − ? cue ? ? + ? ory, one has to search for cues in memory, and search in memory appears to elicit more noncompensatory pro- cesses (bröder & schiffer, ). however, glöckner and bröder ( ) neglect this boundary condition and present inferences from givens as a test of the recognition heuristic (or the “enhanced recognition heuristic”), plac- ing detailed information about “unrecognized” objects before the participants’ eyes while they make decisions. similarly, ayton, Önkal, & mcreynolds ( ) provide cue values about unrecognized objects. their results in- dicate that, in inferences from givens, the model of the recognition heuristic predicts less well than in inferences from memory. yet the authors do not present their result in this way, but claim that in our original article (gold- stein & gigerenzer, ), we also would have tested “in- formation from givens”. yet in none of our studies did we provide cue values for unknown objects. as illustrated by figure , “inferences from memory are logically different from inferences based on external information. if one has not heard of an object, its cue values cannot be recalled from memory” (gigerenzer & goldstein, , p. ). one can test the use of the recognition heuristic outside its boundary conditions to understand the boundary con- ditions themselves, but one should not suggest this as test of the recognition heuristic per se. situations in which no cue values are known about un- recognized objects are fairly common. statistical models deal with such missing values through a process called imputation, and the recognition heuristic is a proposal of how the mind addresses, and in some sense exploits, the missing value problem. at the margin, the name of an unrecognized object itself may suggest cue values (e.g., the name of a product may reveal some attribute values), and there are on occasion cases in which a cue value can be deduced (e.g., someone who can name all the g- countries can deduce that norway is not among them). but unlike in figure , these cue values are inferred, not recalled from memory. . beauty and benefits of simple models complex problems often demand simple solutions, par- ticularly in an uncertain world (goldstein & gigerenzer, ). the beauty of simple models lies in their trans- parency. one can measure how often and in what situa- tions models predict behavior and when they fail. the benefits are in their robustness: the ability of a strat- egy to work well in new situations. a complex model with many adjustable parameters is more prone to overfit- ting than a simple model (czerlinki, gigerenzer, & gold- stein, ). the resulting error can be measured in a quantitaive way using the bias-variance framework (e.g., gigerenzer & brighton, ). future research should steer away from testing the recognition heuristic as a null hypothesis, without the specification of an alternative model. a competitive testing approach for models of recognition-based infer- ence was introduced by marewski et al. ( ), who tested several compensatory strategies and reported that none could predict judgments better than the recognition heuristic. besides competitive testing, a promising fu- ture research strategy is to test whether models can pre- dict multiple phenomena, such as choice and process data (tomlinson, et al. ). it should become standard to measure the performance of models by prediction, such as out-of-sample prediction, not by data fitting. in closing, we would like to thank the contributors to the three special issues of the journal. you helped us to better understand the strengths and limits of the recogni- tion heuristic. references beaman, c. p., smith, p. t., frosch, c. a., & mccloy, r. ( ). less-is-more effects without the recognition heuristic. judgment and decision making, ( ), – . bröder, a. & schiffer, s. ( ). adaptive flexibility and maladaptive routines in selecting fast and frugal deci- sion strategies. journal of experimental psychology: learning, memory, & cognition, ( ), – . bröder, a., & schütz, j. ( ). recognition rocs are curvilinear–or are they? on premature arguments against the two-high-threshold model of recognition. journal of experimental psychology: learning, mem- ory, and cognition, , – . czerlinski, j., gigerenzer, g., & goldstein, d. g. ( ). how good are simple heuristics? in gigerenzer, g., judgment and decision making, vol. , no. , july benefits of simple models todd, p. m. & the abc group, simple heuristics that make us smart. new york: oxford university press. davis-stober, c. p., dana, j., & budescu, d. v. ( ). why recognition is rational: optimality results on single-variable decision rules. judgment and decision making, ( ), – . dougherty, m. r., franco-watkins, a. m., & thomas, r. 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( ). four challenges for cognitive research on the recognition heuristic and a call for a research strategy shift. judgment and decision making, ( ), – . em-jmhj .. the business of black beauty: social entrepreneurship or social injustice? simone t.a. phipps school of business, middle georgia state university, macon, georgia, usa, and leon c. prieto college of business, clayton state university, morrow, georgia, usa abstract purpose – this paper aims to examine the black beauty industry from a historical perspective and consider the fairness heuristic theory to determine if organisations in this industry are engaging in and promoting social entrepreneurship or contributing to social injustice. the paper explores the work of annie turnbo- malone and madame c.j. walker, pioneers and stalwart entrepreneurs in the black beauty business, to discuss the controversial issue. current and future applications are also investigated and presented. design/methodology/approach – papers from earlier as well as more contemporary journals, news media and books were examined and synthesised to render a balanced view to aid in the entrepreneurship or injustice debate. findings – the paper concludes that decisions about fairness and justice involve perception and thus vary by individual, allowing a substantial case for the black beauty industry to both be commended for social entrepreneurship and condemned as a proponent of social injustice (distributive, procedural and interactional). originality/value – organisations have substantial impact on individuals, groups, the community and society. a meaningful organisation encourages expression, perceptions of worth and constructive attitudes and behaviour, and refrains from reflecting excessive dictatorship or dehumanisation. this paper highlights both positive and negative organisational and societal issues concerning the business of black beauty, a relatively understudied topic in management in general and management history in particular, and it provides a unique lens from which to build awareness about entrepreneurship and justice and to effect needed change. keywords social entrepreneurship, justice, fairness heuristic theory paper type general review introduction meaningful organisations care about more than high productivity and profit. yes, these factors are important because without them, the chance of organisational survival diminishes. however, truly meaningful organisations understand that other factors also matter. these organisations value people – both internal (i.e. employees) and external (i.e. members of society) constituents. herman and gioia ( ) explain that this meaningful culture includes elements such as mutual respect, diversity, acknowledgement of the human spirit (e.g. allowing individual expression of values) and social responsibility. these dynamics are often also associated with justice (colquitt, ; jurkiewicz and giacalone, ; roberson and stevens, ; rupp et al., ). as such, one may argue that an organisation that wishes to be described as meaningful should strive to exhibit justice. also, the point should be made that a firm that exhibits business of black beauty received june revised september accepted september journal of management history vol. no. , pp. - © emeraldpublishinglimited - doi . /jmh- - - the current issue and full text archive of this journal is available on emerald insight at: www.emeraldinsight.com/ - .htm http://dx.doi.org/ . /jmh- - - organisational justice is also exhibiting social justice, as the former is related to the latter. lambert ( ) argued that workplace policy constitutes an important form of social policy because it represents the vehicle through which social benefits are distributed by employers. organisations are an important part of society, and their culture, which is reflected by the values they uphold, the norms they accept and the policies they establish, affects society as a whole. in addition to being just and valuing people, meaningful organisations make a positive difference in society. a meaningful organisational culture demonstrates a recognition of the importance of being socially responsible. herman and gioia ( ) affirm that employees, customers and the general public are becoming more aware of company policies and standards, what organisations give back to the community and that societal perceptions do matter. the concept of social entrepreneurship has also been linked to social responsibility and societal enhancement. ilieva-koleva and dobreva ( ) describe social entrepreneurship as an innovative form of business which successfully combines commercial practice and social aims and that it has emerged as a response to chronic social problems (e.g. poverty, unemployment, community fragmentation, etc.). though their specific goals vary, all “social enterprises” endeavour to enhance societal well-being in some way, driven more by their mission than the market or profit (dees et al., ). therefore, an organisation that engages in social entrepreneurship would be characterised by many as meaningful. this paper focuses on the black beauty industry in the early s and therefore begins with an examination of its history, followed by an investigation into its early contributors. it then explains the fairness heuristic theory and its link to justice, to facilitate a deliberation about whether the organisations within this industry could be acclaimed for promoting social entrepreneurship or whether they could be accused of being proponents of social injustice. after both cases for entrepreneurship and injustice are made, a brief look at the current state of the industry is provided. history of the black beauty industry the history of the black beauty industry in the usa can be traced back to slavery. according to black ( ), before the mid-nineteenth century, white women desired creams and preparations (including lighteners) to provide smooth, white complexion signifying the genteel lady, and these preparations were borrowed from a variety of cultures, as well as from the slaves who brought hair and beauty remedies from west africa. soon, slaves living on plantations also realised that lighter-skinned blacks with straighter hair were favoured, as they worked inside the plantation houses where they performed less backbreaking labour than the slaves relegated to the fields, and they had access to hand-me-down clothes, better food, education and sometimes even the promise of freedom upon the master’s death (byrd and tharps, ). in the nineteenth century, commentators noticed that africans and those of african descent stood at the base of the racial hierarchy, and as a display of whiteness- secured privilege, black women also made use of skin lighteners and bleaches (black, ). after slavery, trends did not change much in terms of the connection between appearance and opportunity. byrd and tharps ( ) explained that in the twentieth century, the politics of appearance played a pivotal role in the reconfiguration of black ideas, norms and ideologies as blacks aspired to gain access to the american dream. the authors stated that education and training made little difference if a person looked too african. for example, kinky hair, among other traits, translated to being ignorant, uncivilised and infantile. therefore, blacks did what they could to emulate european standards of beauty, dress and behaviour (byrd and tharps, ). jmh , in the late nineteenth and early twentieth centuries, black women sold hair products (e.g. madame c.j. walker’s straightening comb) in black communities (harvey, ). in fact, the hair salon arose as a supplier of both employment opportunity and beauty treatments. boyd ( ) explained that due to racial segregation, black women were excluded from most jobs and whites in the beauty industry often refused to provide service to black customers. therefore, in response to labour market exclusion, black women became “survivalist entrepreneurs” who targeted a readily available customer segment of other black women. entry into the black beauty industry allowed these women to become fully self-employed or to supplement their income because there was a demand for beauty services from black women who perceived that maintaining a well-groomed appearance was a necessity for securing employment (boyd, ; harvey, ). in addition to hair products and services, the black beauty industry also included cosmetics. for instance, john h. johnson, founder of ebony (the first black-owned mass circulation periodical), launched fashion fair cosmetics after he noticed that his models had to mix foundations to create the right blend for their complexions (jones, ). furthermore, in the late nineteenth and early twentieth centuries, skin-lightening or bleaching products and processes were often manufactured, advertised and sold. according to lindsey ( ), numerous african-american women, impacted by the devaluation of their darker hues and the privileging of white skin, invested in these products and processes to achieve a re- creation of the individual and collective self. by the mid-twentieth century, white-owned companies that sold hair products and cosmetics were also paying attention to the african-american market. for example, jones ( ) revealed that revlon and l’oréal had specific products and brands for african- americans, and avon differed itself by selling brands that appealed to all ethnicities. avon also gained credibility in the african-american market by utilising many black women in its army of neighbourhood sales representatives (jones, ). the black beauty industry provided occupational opportunities via entrepreneurship, as well as access to products and services to an underserved market. with its variety of offerings such as wigs, weaves and hair straightening and skin-lightening products, it also helped facilitate employees’ conformity to the standards and expectations of more conservative organisations that frowned upon more ethnic hairstyles and other aspects of appearance. the industry, along with its offerings and promotional strategies, enabled individuals to fight the falsity that black was unprofessional, unattractive and inferior, so these individuals could be better accepted in the workplace and in society and allowed to progress. early contributors to the black beauty industry annie turnbo-malone ( - ) was an african-american entrepreneur who founded a beauty, haircare and cosmetic business targeting black women and grew it into an empire. she patented, manufactured and distributed beauty products and services (phillips, ), and her products included hair straighteners, pomades (and other haircare products), soaps, face powders, deodorants and creams (including bleaching/skin whitening creams) (ingham and feldman, ; trawick, ). she was so successful that imitators were emerging across the country, and thus, to stymie impostors’ efforts, she adopted and copyrighted the trade name “poro”, a mende word (ingham and feldman, ; phillips, ), under which she continued to build her brand. the daughter of former slaves (witzel, ), turnbo-malone was a pioneer of direct selling in the beauty industry for the african-american market. according to peiss ( ), in the s, malone began to experiment with hair treatments and preparations to solve the business of black beauty problems of hair loss, breakage and manageability black women often faced, and by , she was manufacturing and selling door to door. in , she expanded by moving from illinois to st. louis, mo, where she became well established and continued expansion by travelling throughout the south adopting a sales strategy using agent-operators. the latter were trained and certified in her method, and earned money on hair treatments and a percentage of product sales. they also trained other agents, widening distribution regionally and across the nation (peiss, ). turnbo-malone has been heralded by some as the first black female millionaire in the usa, although others perceive this credit as belonging to another. nevertheless, while this notable claim is still debatable (trawick, ), the estimation of turnbo-malone’s personal wealth in of $ m (miller, ) is remarkable and deserving of recognition. poro became a multimillion-dollar industry that uplifted black women economically and empowered them to resist marginalisation (phillips, ) and turnbo-malone was the entrepreneur who envisioned it and made it a reality. madam c.j. walker ( - ), née sarah breedlove, founded the madam c.j. walker manufacturing company (bundles, ) and was another successful african-american entrepreneur in the beauty and haircare business. in fact, she is arguably better known than annie turnbo-malone, and is the other entrepreneur who is often perceived as the first black female millionaire in the usa. trawick ( ) stated that walker’s story of success has been written and told far more extensively than turnbo-malone’s, and that walker is still identified by some as the first african-american woman millionaire. like turnbo-malone, she was the daughter of former slaves (witzel, ). in fact, coincidentally, she was actually inspired by turnbo-malone. peiss ( ) explained that after years of labouring as a domestic worker and laundress, breedlove entered the beauty business in the early s when she worked briefly as a poro agent in st. louis. breedlove not only tried turnbo-malone’s haircare products after meeting her at a fair in which turnbo-malone ran a stand but she was also offered a job by turnbo- malone as a sales agent, which she immediately accepted, seeing an opportunity to build a better future (ingham and feldman, ; witzel, ). breedlove also gained opportunities for growth and advancement in turnbo-malone’s company. she rose to the rank of chief commission agent in the west, but after differences arose, breedlove developed her own range of haircare products targeting the black female market (witzel, ). she moved to denver in , and like turnbo-malone, began house to house canvasses among african- americans and trained agents (peiss, ). her products included skin care and skin whitening products, and haircare and hair straightening products (including a special comb that would help straighten hair) (lommel, ; trawick, ). thus, turnbo-malone’s employee and mentee became her competitor. sarah breedlove became madam c.j. walker after marrying charles j. walker. her first husband died in an accident when she was only years old (bundles, ). mr walker, an advertising executive, helped grow the business and suggested, among other things, that she rebrand herself and her business, as such an imposing name (i.e. madam c.j. walker) would add status to her products (witzel, ). his advice was indeed useful and, although not the only reason, madam c.j. walker’s business increasingly flourished. according to her great–great-granddaughter (and biographer), a’lelia bundles, madam c.j. walker was one of america’s wealthiest self-made businesswomen at the time of her death and in life, she was so financially successful that she was known as the wealthiest african-american woman and given the title millionaire before she was actually one (bundles, ). she constantly used her wealth to help her community and like turnbo- malone, she uplifted black women economically and socially. according to trawick ( ), jmh , madam c.j. walker created financial independence and opportunities for african-american women all over the world through beauty culture. both annie turnbo-malone and madam c.j. walker achieved unusual success in manufacturing and marketing haircare products for black women (peiss, ) and used their agent network and wealth to promote social issues (keep and vander nat, ). justice and the fairness heuristic theory heuristic methods or processes facilitate self-directed learning, allowing individuals to discover or understand dynamics or to solve problems on their own. heuristics are relevant to justice because people form their own judgements of what is (or is not) fair based on the information they have and their interpretation of it. according to van den bos et al. ( ), the fairness heuristic theory proposes that people use fairness judgements when they are concerned about potential problems associated with social interdependence and socially based identity processes, referred to as the “fundamental social dilemma”. the latter is concerned with the question of whether one can trust others not to exploit or exclude him/ her from important relationships or groups, and the fairness heuristic theory argues that people start looking for fairness information to answer this question (van den bos et al., ). colquitt and rodell ( ) explain that the fairness heuristic theory suggests that individuals in organisations face this fundamental social dilemma wherein cooperating with authorities can lead to better outcomes but can also increase the risk of exploitation, and in an effort to cope with the dilemma, individuals use a “fairness heuristic” as a shortcut to determine if to accept authority and cooperate. fairness information is used as a “heuristic substitute” to decide whether or not an authority can be trusted (van den bos et al., ). one can argue that in general, individuals in society face this same fundamental social dilemma. organisations have a culture, usually established and sustained by organisational leaders, who are the ones in authority, and good organisational citizens are expected to conform to the norms of that culture. in the same way, there is national culture (which organisations often reflect), and individuals within a nation must determine whether to cooperate, and adapt to the norms that authorities deem suitable. analysis of culture and its implications do not have to focus only on one tier, as relevant factors are usually not limited solely to the organisational level or solely to the societal level of analysis. there is overlap. as stated by schminke et al. ( ), most individuals are members of many more organisations than those in which they work (e.g. professional, community, political, religious, recreational and civic groups), and they all represent social systems and reflect similar processes by which individuals make sense of their environments. the authors also mentioned the possibility of “top-down” effects as social institutions exert enormous pressures on organisations and their employees to conform to certain practices and behaviours (schminke et al., ). appearance norms are customary for both organisations and society at large, and expectations regarding professionalism and beauty are set according to these norms. some may assert that the black beauty business has helped to shape perceptions and bolster certain norms. will ceding to authority about appearance norms lead to better outcomes or exploitation? a historical examination reveals support for both sides. one can look at the information and form fairness judgements. van den bos et al. ( ) clarified that the most common approach to the resolution of uncertainty that is caused by having to cede to authority is to refer to impressions of fairness and form fairness judgements. business of black beauty fairness judgements imply decisions about justice. research in organisational and social justice has introduced three types of justice (bacha and walker, ; schminke et al., ). distributive justice pertains to the fairness of outcomes, procedural justice pertains to the fairness of processes used to determine outcomes, and interactional justice pertains to whether or not one receives treatment that reflects respect and dignity. does the individual’s input of conformance (facilitated by the black beauty industry) to appearance norms lead to favourable outcomes and are these outcomes fair? should conformity to these appearance norms be considered as part of the process to determine outcomes? does the expectation of compliance with appearance norms reflect interpersonal treatment with respect and dignity? these fairness judgements may be formed based on the information presented in this paper, as a determination is made concerning whether the black beauty business is linked to positive societal impact (i.e. social entrepreneurship) or organisational and societal unfairness (i.e. injustice). according to gill ( ), the black beauty industry since its inception has served as an incubator for black women’s political activism and a platform from which to agitate for social and political change. the black beauty industry: the case for social entrepreneurship descriptions of social entrepreneurship vary. dees ( ) explained that social entrepreneurs adopt a mission to create and sustain social value, pursue new opportunities to serve that mission, engage in continuous innovation, adaptation and learning and exhibit a heightened sense of accountability for outcomes created and to constituencies served. defourny and nyssens ( ) mentioned that the very nature of the social enterprise is that it presupposes a certain balance between its two major elements, the economic (i.e. taking risks and being market-oriented to create income and finance the enterprise) and the associative (i.e. meeting emerging but non-remunerative social demands). campi et al. ( ) mentioned three elements of the social enterprise, namely the economic, the social and the socio-political or civic (i.e. promoting democratisation of decision-making and the inclusion of marginalised parts of the population). the main idea is that social entrepreneurship innovatively blends the acquisition of business goals and social enrichment. austin et al. ( ) explained that definitions of social entrepreneurship range from broad (inclusive of for-profit, non-profit and hybrid sectors) to narrow (non-profit sector), but that regardless of the characterisation, the common thread is the underlying drive to create social value. it may be argued that some of the key ways the black beauty industry historically created (and still create) social value include employment, philanthropy, self-worth and social acceptance. increased employment opportunities have been generated due to the black beauty industry. ingham and feldman ( ) noted that turnbo-malone developed an efficient franchising system, and recruited women, whom she then trained to administer and sell her line of products. these ladies were her aforementioned sales agents (like sarah breedlove, later known as madam c.j. walker). in the usa, branches were established in major urban centres such as miami, los angeles, wa, baltimore, detroit, chicago, new york city, newark, philadelphia, pittsburgh, ks city, omaha, cincinnati and cleveland; and worldwide, african-american women represented the poro product line in areas in canada, the philippines, the caribbean, africa and south america, creating almost , jobs in total (ingham and feldman, ; trawick, ). these women would have had few other (if any) professional opportunities. according to phillips ( ), most black women at the time were restricted to working as domestics or other marginalised jobs. turnbo-malone provided thousands of jobs in a variety of capacities including representatives, teachers and factory workers (ingham and feldman, ). jmh , madam c.j. walker and her manufacturing company also opened doors to financial freedom. bundles ( ) wrote that her great–great-grandmother was an early advocate of women’s economic independence and that she provided lucrative incomes for thousands of african-american women who otherwise would have been consigned to jobs as farm labourers, washerwomen and maids. in fact, her company had trained and employed about , black female agents worldwide (ingham and feldman, ). the black beauty industry has also enabled increased philanthropy. the latter is often associated with sizeable financial donations to worthy causes, as in porter and kramer ( ) consideration of corporate philanthropy, but philanthropy, in a more general sense, can arguably refer to any kind of contribution that supports and benefits the well-being of others and promotes their welfare. charitable giving does not have to be solely monetary. sulek ( ) considered a plethora of definitions of philanthropy, from ancient to modern times, including goodwill to fellowmen especially active effort to promote human welfare; general benevolence; the private giving of time or valuables (money, security and property) for public purposes; the voluntary giving and receiving of time and money aimed towards the needs of charity and the interests of all in a better quality of life; and the disposition or active effort to promote the happiness and well-being of others. therefore, ideally, philanthropy embraces any action (financial or otherwise) geared towards doing good for others and meeting their needs so that their welfare is positively impacted. according to the common and ideal definitions, one may assert that turnbo-malone was certainly a philanthropist, and poro was a social enterprise that engaged in corporate philanthropy. turnbo-malone has been credited with making many sizable charitable donations. ingham and feldman ( ), miller ( ), and trawick ( ) stated that her activities and energies transcended her business interests as demonstrated from the money she gave to a variety of black organisations, including an orphanage, hospitals, churches and schools, to how she depicted her race in advertisements. also, in one of st. louis, mo’s black neighbourhoods, she constructed poro college, which served as a factory and beauty-training school, and incorporated much more than simply the company’s operations, as it included many amenities including (but not limited to) modern classrooms, auditorium, cafeteria, bakeshop, dormitory, guest rooms for travellers, business offices and facilities to accommodate needs of religious, fraternal, civic and social functions (ingham and feldman, ). in those days, access to such amenities was quite limited for black individuals. hence, turnbo-malone’s vision and provision facilitated inclusion, as minorities could take advantage of particular social experiences formerly outside their reach, or at least, they lessened the blow of general exclusion. according to ingham and feldman ( ), prominent black figures were guests at the poro complex, and other blacks who were denied admittance to venues in the city’s popular restaurants and hotels were welcome to use the modern facilities at the so-called “showplace of st. louis”. turnbo-malone and her company provided opportunities and did substantial good to benefit both employees and the community at large, and could thus be commended for philanthropy. madam c.j. walker was also a philanthropist who donated money to worthy causes, created training opportunities, and served as an activist, fighting against social evils. bundles ( ) explained that walker reconfigured the philosophy of charitable giving in the black community with her unprecedented contributions to organisations such as tuskegee institute, the ymca and the naacp; and that she was also a political activist protesting lynching and racial injustice. walker also opened lelia college and at least one other training school to train and develop hair culturists and walker agents, who were also allowed to sell walker products and open beauty salons that practiced the walker method of business of black beauty treating hair (bundles, ; stille, ; trawick, ), thus providing the instructional foundation many needed to seek financial security and a better life. her many contributions, monetary and otherwise, met both economic and social needs that were essential for the welfare of others. according to bundles ( ), madam walker paved the way for the profound social changes that altered women’s place in the american society. the case can also be made for the black beauty industry helping to facilitate self-worth and social acceptance for minorities, and thus, added professional opportunities as a result of the increased acceptance. phillips ( ) mentioned that during the jim crow era, many whites considered “a beautiful black woman” an oxymoron, and this affected black women’s sense of self and restricted their opportunities in the job market. black women who were seeking white-collar jobs such as stenographers, telephone operators, receptionists and clerks, had difficulty in obtaining employment in these jobs, and needed straight hair and light skin to have a chance of obtaining these positions, as they were usually closed to anyone known to be coloured (boyd, ; drake and cayton, ). the strategic use of beauty culture affirmed their beauty, sustained their self-worth and ensured their economic well-being, thus uplifting them psychologically and socially (phillips, ). the author explained that turnbo-malone helped transform black women’s lives by creating a platform for racial uplift as much as commerce, tying disparate groups of colonised women together as poro agents, and meeting many of the psychological, social and economic needs of african-american females in a white-dominated political economy, as she generated and expanded their opportunities for mobility. madam c.j. walker also played a role in increasing self-worth and social acceptance for black women. stille ( ) mentioned that walker taught her agents to feel special and beautiful, but also gave them a deeper meaning of beauty. in addition, one of walker’s graduates appreciatively declared that walker opened up a trade for hundreds of coloured women to make an honest and profitable living (stille, ). today, the black beauty industry has also been credited with the provision of employment opportunities, philanthropy and the facilitation of increased self-worth and social acceptance. currently, black beauty salons are a large sector of american business, and in recent years, there has been significant growth in black female entrepreneurs in this arena (wingfield, ). in addition, companies that promote skin-lightening products geared towards black individuals and other minorities with darker complexions are finding ways to give back to society. for example, unilever markets a skin cream called “fair and lovely” to india and countries in africa (including kenya, zambia, zimbabwe, uganda, tanzania, cote d’ivoire, egypt, malawi, rwanda and mozambique) for lightening the colour of dark-skinned women (davidson, ; karnani, ; unilever, ). the company has also launched project shakti in india and africa to address social issues like poverty, women empowerment, and education, by bringing profitable micro-enterprise opportunities for rural women (kreckova, ). as regards self-worth and social acceptance, african- american women associate well-styled hair with beauty, confidence and self-esteem, so the close relationship between a nice hairstyle and feelings of self-worth translates into african- american women accounting for per cent of all hair maintenance business in the usa, despite african-americans only comprising per cent of the us population, due to a history conveying that straightened black hair is necessary for acceptance and advancement (stenson, ). considering the information on the positive contributions of employment, philanthropy, self-worth and social acceptance that may be partly attributed to the black beauty industry and its pioneers, one may use heuristics in general and the fairness heuristic theory in particular, to interpret the information and decide whether this industry, and the jmh , organisations and business owners within could be trusted not to exploit and/or exclude individuals and groups. based on the information, one may assert that many internal and external constituents benefited from better outcomes and experienced inclusion, emancipation and justice, rather than exclusion, exploitation and injustice. employees of poro, madam c.j. walker manufacturing company and other companies still existent in the industry, as well as community members and others in society at large who have gained opportunities (or heard of others gaining opportunities) owing to the industry and its affiliates may form the judgement that the black beauty industry is indeed comprised of social entrepreneurs. they may form the judgement that the industry and its affiliates can be trusted and should receive cooperation to continue their admirable work; and that the organisations are meaningful and a valid representation of social entrepreneurship as they help address social problems and assist in the promotion of social enrichment. the black beauty industry: the case for social injustice it was previously mentioned that some may argue that the black beauty culture helps to inspire and sustain self-worth and a sense of self. however, arguments may also be made to show how the black beauty industry does the exact opposite, undermining self-worth and destabilising one’s sense of self. some may assert that the main setback partly attributable to the black beauty industry is an arguably apparent loss of identity. identity plays an important role in organisations, and is therefore acknowledged as an essential organisational construct that can help explain attitudes and behaviours. identity is associated with several other organisational constructs including job satisfaction, organisational commitment, performance and turnover intentions (cole and bruch, ; van dick et al., ; voss et al., ). an individual’s identity is related to his/her sense of self, and allows the person to ascertain who he/she is. when the individual experiences loss of that identity due to organisational and societal values or ideologies that are also reflected by the black beauty industry, there is organisational and social injustice. hair and hairstyle are essential part of embracing one’s identity, and in the case of black hair, that identity is not only african-american. according to byrd and tharps ( ), the story starts in africa, where hair and hairstyle have intrinsically held social, cultural, spiritual and aesthetic significance for centuries, and have been fundamental aspects of individuals’ and groups’ sense of self. today, many individuals wish to wear their hair “natural” (i.e. unaltered by chemicals or other straightening methods) or in an african style (e.g. locks) to celebrate their link to their original homeland, (re)claim their identity, and/or demonstrate their pride in who they are as people of african origin. however, despite the desire to embrace their identity, due to history that seems to repeat itself in different ways, there is often concerned pause. as individuals use a “fairness heuristic” to help decide whether or not authority can be trusted, and if to accept authority and cooperate by conforming to appearance norms, they may make their own judgements about the worth of conformance to them. they may deem it worthwhile if it results in better outcomes for them, but it also depends on the value placed on certain outcomes. for example, for one individual, a promotion may be considered a better outcome, and thus worth conformity, but for another, the value of the promotion is diminished if the cost of conformity is his/her identity or sense of self, and then, it may be interpreted as exploitation. individuals may also strive to determine the worth of conformance through fairness judgements of a distributive, procedural or interactional nature. distributive justice pertains to the fairness of outcomes. conformity to appearance norms may lead to favourable outcomes. however, are these seemingly expedient outcomes fair? business of black beauty hurley-hanson and giannantonio ( ) made the point that physical attractiveness, personal appearance and image are important influences on organisations’ employment decisions regarding hiring, promotion and compensation. applicants may decide to conform to the image norm of the organisation (e.g. via hair extensions or straightening) to be perceived as a good fit and get the job. some may argue that this is a fair outcome because everyone is expected to conform to some degree to be hired. for instance, some individuals may exhibit conformity through the opinions they voice. according to jones ( ), ingratiation is the use of specific actions such as opinion conformity, other enhancement and favour doing in an attempt to increase the target person’s liking of the individual. higgins and judge ( ) found that ingratiation had a positive effect on perceived fit and recruiter hiring recommendations, and indirectly on receipt of a job offer. however, conforming one’s opinions and conforming one’s image are very different actions. in the grand scheme of things, conforming to image norms to gain a desired outcome such as a job offer, and in the process, losing one’s identity, may be likened to the proverbial gaining of the world but losing the soul. this may be considered by some to be the greatest distributive injustice. procedural justice concerns the fairness of processes used to determine outcomes. it has been found that many employment decisions are the result of a process of elimination according to a variety of image perceptions. as aforementioned, one such image perception is physical attractiveness. the latter has been associated with more favourable occupational decisions and outcomes such as suitability for hire, higher earnings/income, higher overall performance ratings and organisational progression (drogosz and levy, ; judge et al., ; marlowe et al., ). the meta-analytic research of hosoda et al. ( ) also failed to show that the physical attractiveness bias is stronger when decision makers have less job-relevant information, suggesting that even when decision makers have job-relevant information, they may still use attractiveness information in making decisions. this finding supports the argument that although attractiveness may not be the most important determinant of personnel decisions, it may be the deciding factor when there are applicants with similar qualifications or records of job performance (hosoda et al., ). quite often, physical attractiveness is associated with whiteness. blay ( ) noted that queen elizabeth i’s already pale complexion, further aided by cosmetics and whitening commodities, was the inspiration for the elizabethan ideal of beauty that was popular in europe, later adopted in the usa (including communities of colour), and now a widespread global phenomenon (including several countries in africa). as whites are often perceived as more attractive, and attractiveness is organisationally and socially useful, it is not surprising that whites benefit from better organisational and other social experiences, opportunities and outcomes. for instance, a study by greenhaus et al. ( ) indicated that whites were rated higher on job performance and received higher promotability assessments, whereas blacks were more likely to be at career plateaus and reported having less job discretion and lower feelings of acceptance. it is also not surprising that blacks often attempt conformity to “white” beauty ideals, aided by products offered by the beauty industry. these attractiveness perceptions are biased, and one may argue that conformity to appearance norms, fashioned on the basis of these attractiveness perceptions, should not be considered part of the process to determine outcomes, whether consciously or subconsciously. such process considerations may be deemed procedural injustice. interactional justice involves whether or not one receives treatment that reflects respect and dignity. gatison ( ) noted that black women and girls constantly are confronted with the reigning standard of beauty – long, straight hair, light or white skin and thinness – as television, music videos and magazines are the main purveyors of this standard, along with jmh , trendsetting celebrity users of products that endorse the standard. this prejudiced standard is not relegated to entertainment (which already impacts numerous aspects of society) only, but bleeds its way into other industries and their organisations as well. in fact, beauty is linked to professionalism. the latter connotes attitudes and behaviours that reflect characteristics such as expertise, ethics, commitment and collegially maintaining standards (bruce and ahmed, ; kerr et al., ). beautiful or physically attractive individuals have been found to be perceived as possessing attributes like expertise, trustworthiness and likeability (ahearne et al., ; liu et al., ), which aligns with the “beautiful is good” stereotype (lorenzo et al., ). trustworthiness is associated with ethics and commitment (bews and rossouw, ; colquitt et al., ), and likeability, especially for women, with collegiality and maintaining standards (bolino and turnley, ). it is no wonder, then, that those perceived as beautiful benefit from employment and organisational and other social progression opportunities. it is very likely that they are often perceived as professional as well. as whiteness is associated with beauty and professionalism, blacks may feel the need to conform to benefit from opportunities as well, even at the expense of identity. rosette and dumas ( ) noted that many recognise the importance of projecting a professional image at work, and the role that their demeanour, clothing and grooming play in successfully crafting this image, but minority women in particular suffer a disadvantage in crafting this image due to negative stereotypes, lower expectations and workplace norms that run counter to their cultural values and reward white standards of behaviour and appearance. the authors explained that minority women often feel they must compensate for both their gender and race in attempting to present a professional image that renders them credible, and hairstyling is one of the most central decisions in managing perceptions. long, straight hair has generally been considered the gold standard for attractiveness and the expectation of a straight, conservative hairstyle is present in corporate organisations, but because of the fundamental, physical differences between white and black hair textures, a great deal of time and a variety of expenses are required to transform black hair to conform to traditional (i.e. white) workplace norms for appearance (rosette and dumas, ). it may be contended that the very expectation of compliance with these appearance norms insinuates inferiority of those that do not “naturally” fit the standard and emanates a signal for interpersonal conduct that overlooks respect and denies dignity, hence demonstrating interactional injustice. some may argue that the black beauty industry should not be blamed for the injustice (s) perpetuated by organisations and societies that do not truly embrace diversity. they may argue that these organisations and societies are the ones that should be criticised for not being meaningful. however, it may also be argued that the black beauty industry, with its products that promote straight hair and light skin as the mark or standard of ideal beauty and/or true professionalism, helps facilitate the erosion of identity and pride in one’s identity, and contributes to the preservation of the myth that characteristics of blackness are to be viewed as negative both professionally and by extension, socially. thus, with this in mind, the judgement may be formed that the industry and its affiliates help pressure members of society (including organisational leaders who make decisions, and employees who want to succeed) to conform, and therefore, to be exploited, for fear of exclusion if they decide to stay true to their identity or encourage others to stay true to theirs. far from meaningfulness and social entrepreneurship, this would be the case for social injustice. business of black beauty current state of the black beauty industry the beauty industry is a global, multi-billion-dollar industry encompassing numerous products and services. according to jones ( ), the beauty industry overlaps with many others including fashion, beauty salons and hairdressers, as well as medical products and services such as botox and plastic surgery; and consumers around the world spend $ bn a year on hair and skin care products, fragrances, colour cosmetics, toiletries and other merchandise. this was a estimate, and thus, the size of the industry today is in all probability represented by a much larger figure. in fact, the black beauty industry alone, which can be described as a subset of the general beauty industry, is also a global industry arguably worth billions of dollars. opiah ( ) asserted that the black haircare industry, specifically is grossly underestimated and quoted market research firm mintel, which estimated the size of the market at $ m, with a projection of $ m by . mintel clarified, however, that general market brands, weaves, extensions, wigs, independent beauty supply stores, distributors, e-commerce, styling tools and appliances were missing from the figures (opiah, ). therefore, if all relevant products and services were included, the evaluation would be substantially higher. the $ m could reach half trillion dollars (i.e. $ bn), according to mintel (opiah, ). if the black haircare industry alone is so significant in size, one can only imagine the magnitude of the black beauty industry in general. today, the black beauty industry still promotes products and services such as hair straighteners and lightening creams that some would argue encourage the masking of black features in favour of adopting the historically white standard of beauty, thus defying the idea that black is naturally beautiful and professional and preventing a genuine embracing of diversity. as aforementioned, these products and services are not only marketed in the usa, but worldwide. for example, skin lighteners are rife in the continent of africa. thomas ( ) highlighted abraham and solomon krok (twin brothers born to jewish immigrant parents), who dominated the region’s skin lightener market and amassed a fortune from the manufacture and sale of skin lighteners to black south africans until a ban on skin lighteners was passed and apartheid ended. ironically, these brothers who earned their wealth by profiting from a system that classed blacks as inferior, pushing them to become consumers of dangerous products they viewed as enabling them to elevate their status, later became the financiers of the much-admired apartheid museum in johannesburg. according to thomas ( ), like many other whites, the kroks sought to forge reputations better attuned to post-apartheid politics, through projects like the apartheid museum, which memorialises those who suffered and/or died under the racist south african state. despite the ban, many in south africa still use skin lighteners. skin- lightening/whitening/bleaching products are widespread in south africa, nigeria, senegal, mali, togo, cote d’ivoire (ivory coast), zambia, ghana and other african countries, and it seems that in many parts of the african continent, skin bleaching is nothing less than a way of life (blay, ; kpanake et al., ; roby, ). although products and services that debatably aim to conceal black physical traits are still very popular, some individuals have accepted the charge to introduce and promote products that celebrate natural black beauty and black identity. for example, grace amey- obeng, a successful ghanaian entrepreneur, has become a millionaire by advising against skin bleaching and promoting products that emphasise the beauty of the black skin. according to bbc news ( ) and cnn ( ), amey-obeng’s empire, which includes a beauty clinic, a firm that supplies salon equipment and cosmetics and a college (which has trained more than , young people, mostly women), has eight branches in ghana, and exports to nigeria, burkina faso, togo, ivory coast, switzerland and the uk. bbc news jmh , ( ) quoted amey-obeng as noticing that “the women had destroyed their skin with bleaching products”, and seeing “the need to assist them because otherwise it would become a social problem”. in the usa, another example is lisa price, the founder of carol’s daughter, a line of natural beauty products for hair and skin, and also a provider of fragrances/body sprays. the company’s mission is to fulfil the beauty needs of the diversity of skins that make up the tapestry of our world by creating high-quality hair, body and skin care products, made with natural ingredients (carol’s daughter, ). due to wording that demonstrates that all are welcome to use her products, on the surface, the mission may connote that the products are not geared towards black consumers. however, carol’s daughter is considered to be a black-owned company that mainly targets the black audience. zukin ( ) described it as a black-oriented cosmetics firm. byrd and tharps ( ) classified it under black-owned manufacturers of black hair products. although the wall street journal revealed carol’s daughter’s acquisition by beauty industry giant l’oréal (gleason, ), lisa price was expected to remain creative visionary and spokesperson for the brand, and to continue to lead product development (bates, ), thus retaining creative control, and ensuring the continued authenticity of the brand and its commitment to its main target audience. according to market research firm mintel’s multicultural analyst, roberts ( ), there is a natural hair trend, and several brands of natural haircare products that nearly died have resurrected, and in some cases, rebranded and recreated themselves and their image. in addition, some marketers have incorporated tried-and-true home ingredients in products aimed at the black community (roberts, ). with this natural hair trend, and an increasing number of products and services that promote black hair and acknowledge its beauty, fewer women may feel the intense pressure that exacerbates their desire or need to straighten their hair in conformity with societal expectations of professionalism or ideals of beauty. discussion and future inquiry this examination of the black beauty industry and its effects bring to mind a particular brewing company’s effort to market a malt liquor to urban blacks. according to brenkert ( ), heileman brewing company sought to market “powermaster”, which contained an amplified percentage of alcohol, to inner-city blacks, using black male models and advertisements assuring consumers that the malt liquor was “bold not harsh”. in this case, fairness perceptions and views about moral and social responsibility could very much vary. some may consider that the product instilled a sense of courage, power and worth in a frequently dehumanised segment of the population, while others may claim that it unjustly exploited an already vulnerable target market. brenkert ( ) concluded that when products targeted at particular market segments cause consumers to suffer disproportionately, it is only fair that measures be considered to reduce the harm produced, and that both individuals and corporations should accept collective responsibility to the targeted market segments for the effects of their products and marketing campaigns. fairness heuristic theory helps explain how justice evaluations are formed. the theory argues that individuals are often placed in the fundamental social dilemma (lind, ). they encounter situations where they must cede to authority, providing an opportunity to achieve their goals and secure social identity, or a risk to lose their identity and be exploited, excluded and rejected (cropanzano et al., ). thus, they make decisions about whether the authority can be trusted to be fair and nonbiased, and to view and treat them as legitimate members of the work group, organisation, or society (cropanzano et al., ). business of black beauty as individuals form their justice evaluations pertaining to organisational and societal norms (including appearance norms), as well as the industry that helps propagate those norms, they may consider whether society benefits or endures disadvantages due to the standards or customs upheld and deemed acceptable. they may also consider the magnitude or degree of significance of the benefits or disadvantages. future inquiry can shed further light on the “fairness” of the black beauty industry by not only exploring the issue through the lens of distributive, procedural, and interactional justice, but also via the use of various ethical frameworks. for instance, utilitarianism is the ethical theory that advises one to choose the action that maximises the welfare of the most people or supports the greatest good for the greatest number of people (donaldson and dunfee, ); whereas deontology is a morality of principles instead of consequences, where individuals are encouraged to accept it as their duty to do what ought to be done based on what should be universally right (van staveren, ); and the rights principle is one of entitlement, protecting a person’s interests, and asserting that the morally correct action is the one that the person has a moral right to do, that does not infringe on the moral rights of others, and that furthers the moral rights of others (schumann, ). examination of these ethical frameworks may provide further insight regarding the benefits and disadvantages of the black beauty industry, and help lay a foundation for judgements to be formed. further investigation of ethical frameworks is especially valuable because they may overlap with the law. although moral rights are not synonymous with legal rights (ferrell and gresham, ), in some cases, they are one and the same (e.g. freedom of speech, as long as the speech does not infringe on the rights of others). some may argue that an individual’s rights are infringed upon when they are expected to conform to an organisation’s appearance norms. lawsuits document the complexities associated with grooming decisions for black women in professional settings, and several cases show that hairstyle and garb choices (e.g. braids, dreadlocks, african clothing) may have serious repercussions (rosette and dumas, ). if not overt discrimination, one may consider whether the expectation of such conformity can be considered a micro-aggression, where blacks are consciously or subconsciously sent disparaging signals that they and their culture are inferior, thus insulting them and making them feel excluded and unwelcome. these issues warrant further attention. with the eating away of manifestations of identity comes the disregard for the importance of diversity. herman and gioia ( ) noted that diversity, placing emphasis on celebrating differences among people and making active use of the varied perspectives that workers bring to the job from different backgrounds, is much more than a racial issue. diversity facilitates learning, growth and organisational and societal success. future research should explore whether the beauty industry in general and the black beauty industry in particular could help shape perceptions so that black beauty and professionalism is not judged by conformity to white appearance norms. if perceptions are changed, organisations and societies may be more prone to embracing diversity in its totality. jones ( ) mentioned that historically, the commercial beauty industry made no provision for blacks’ distinctive hair texture or skin tones, and that the treatment of black hair became the basis for a large ethnic beauty industry and a fertile area for black entrepreneurs. possibly, if all entrepreneurs (and not only the black ones) in the industry made the effort to promote products and services that highlighted black features and portrayed them as beautiful and professional, perceptions would be changed, and diversity would not only be tolerated but enthusiastically accepted and endorsed. it should be noted, however, that perceptions vary according to individuals and the lens through which they view issues, as their lenses may be crafted differently due to jmh , background, culture, experiences and other factors. therefore, future inquiry should take variables such as race, gender and nationality into account. for instance, jones ( ) stated that although the beauty industry is global, it has some decidedly local characteristics. this is also true for the black beauty industry. thus, variables like race, gender and nationality may influence not only perceptions of beauty and professionalism but judgements about the black beauty industry as well. conclusion as the fairness heuristic theory is used to form judgements about the black beauty industry, and the information is considered, individuals will have their own perceptions and interpretations of what is good and fair and some may determine that they are caught between the proverbial rock and hard place. can the black beauty industry and the organisations and leaders/decision-makers within be trusted not to exploit internal and external constituents’ biases and insecurities knowingly or unknowingly thrust upon them by society? are they, in fact, valiantly serving constituents by helping them to avoid exclusion (e.g. from employment in certain organisations); or are they further propagating unfair stereotypes, thus assisting in the facilitation of exclusion of those who choose not to conform and exploitation of those who do conform? do they deserve cooperation? the information in this paper presents valid arguments for both positive and negative outcomes of the black beauty industry, and thus, the same industry that can be commended for social entrepreneurship can also be condemned for social injustice. this disparity in perceptions is understandable because social enterprises essentially strive to combine business ventures and social missions and when this combination occurs, perspectives about what matters and what makes strategic sense may differ. smith et al. ( ) state that social missions and business ventures are associated with divergent goals, values, norms and identities, and attending to them simultaneously creates tensions, competing demands and ethical dilemmas. thus, it may be argued that for the black beauty industry to survive in terms of business, some social missions can be pursued while others must be overlooked. organisations need to choose their priorities regarding social missions and their choices may not be the priorities of the individuals who consider the information and form their judgements and justice evaluations. these individuals may have different value systems that influence their interpretations of what is good and fair. gill ( ) named economics and entrepreneurship as important variables in black women’s activism and community building and argued that the beauty industry played a crucial role in the creation of a modern black female identity. certainly, pioneers like annie turnbo-malone and madam c.j. walker, as well as more recent black entrepreneurs in the beauty industry like grace amey-obeng and lisa price have been instrumental in contributing to the upliftment of their communities in numerous ways. in fact, trawick ( ) did assert that assumptions regarding black entrepreneurs (like turnbo-malone and walker) as villains preying on their race to capitalise on products/services that physically transform them into white ideals of beauty often were not true; although the author did admit that advertisements promoting straightening kinky hair and bleaching dark skin were discovered. according to madam c.j. walker’s great–great-granddaughter, straight hair was not walker’s primary goal, but better employment and financial opportunity were her main concerns; and wanting to have hair (her scalp had bald spots) had nothing to do with mimicking whites (bundles, ). although gill ( ) credited the beauty industry with playing a crucial role in the creation of a modern black female identity, some may argue that the industry helped facilitate the destruction of black female identity. wingfield ( ) argued that black business of black beauty women’s history of entrepreneurial work in the hair industry represents the influence of systemic gendered racism; where historically, not only were blacks inferior to whites but also black women were precluded from achieving dominant ideals of femininity (and beauty) and thus experienced economic exploitation. according to wingfield ( ), black female entrepreneurs responded to this systemic gendered racism by engaging in business ownership in a field shaped by these messages, therefore creating and selling products that enabled black women to conform. research has already shown that perceptions instigate differential treatment for blacks and whites in organisations and in society. for example, bertrand and mullainathan ( ) found that job applicants with white-sounding names like emily or greg received per cent more callbacks for interviews than job applicants with black-sounding names like lakisha or jamal and that callbacks were also more responsive to resume quality for white names than black ones. one’s name is part of his/her identity. yet, as applicants with black names find it hard to overcome the hurdle in callbacks even by improving observable skills or credentials (bertrand and mullainathan, ), they may find it necessary to resort to changing their names or using a more “white” version of their names. in fact, long before the job search, parents are considering these biases when choosing names for their children. before children are even born, some parents are concerned that a uniquely black name would lessen the chances of that child being cleared for a job interview (ghatt, ), and thus, these parents decide to “toe the line”. conformity to image norms may be seen by blacks as another way to influence perceptions when they pursue opportunities. thus, they may choose to use “beauty” products that enable them to appear more “white”, hence, denying a part of their identity. all organisations (whether in the black beauty industry or not) should be aware of the social (including professional) issues faced by minorities, and do their part to address them. yes, increased employment opportunities and philanthropy are essential, but so are feelings of self-worth (without having to conform to ideals that betray one’s identity) and true acceptance of those who may be different. thus, organisations must avoid being “modern plantations”, and also promote impartiality and eliminate prejudice in whatever form it may take. in doing so, they will be striving to engage in entrepreneurship with a social conscience, and thus, to nurture a more meaningful organisation in particular, and just society in general, where the justice is distributive, procedural and interactional. references ahearne, m., gruen, t.w. and jarvis, c.b. 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( ), naked city: the death and life of authentic urban places, oxford university press, new york, ny. for instructions on how to order reprints of this article, please visit our website: www.emeraldgrouppublishing.com/licensing/reprints.htm or contact us for further details: permissions@emeraldinsight.com jmh , https://mospace.umsystem.edu/xmlui/bitstream/handle/ / /research.pdf?sequence= https://mospace.umsystem.edu/xmlui/bitstream/handle/ / /research.pdf?sequence= http://www.unilever-esa.com/our-brands/detail/fair-and-lovely/ /?wt.contenttype=view&hx ; brands http://www.unilever-esa.com/our-brands/detail/fair-and-lovely/ /?wt.contenttype=view&hx ; brands the business of black beauty: social entrepreneurship or social injustice? introduction history of the black beauty industry early contributors to the black beauty industry justice and the fairness heuristic theory the black beauty industry: the case for social entrepreneurship the black beauty industry: the case for social injustice current state of the black beauty industry discussion and future inquiry conclusion references munich personal repec archive keynesian beauty contest, accounting disclosure, and market efficiency gao, pingyang the university of chicago - graduate school of business june online at https://mpra.ub.uni-muenchen.de/ / mpra paper no. , posted jul : utc keynesian beauty contest, accounting disclosure, and market efficiency∗ pingyang gao† yale school of management october, abstract this paper examines the market efficiency consequences of accounting disclosure in the con- text of stock markets as a keynesian beauty contest, an influential metaphor originally proposed by keynes ( ) and recently formalized by allen, morris, and shin ( ). in such markets, public information plays an additional commonality role, biasing stock prices away from the consensus fundamental value toward public information. despite this bias, i demonstrate that provisions of public information always drive stock prices closer to the fundamental value. hence, as a main source of public information, accounting disclosure enhances market efficiency, and transparency should not be compromised on grounds of the keynesian-beauty-contest effect. ∗i am grateful to seminar participants at yale university, the aaa northeast region meeting, and the aaa chicago meeting. i sincerely thank rick antle, paul fischer (discussant), john geanakoplos, jonathan glover, dong lou, brian mittendorf, robert shiller, shyam sunder, jacob thomas, robert e. verrecchia, varda yaari (discussant), hongjun yan, frank zhang, and yun zhang for helpful comments. all errors are my own. †email: pingyang.gao@yale.edu introduction i investigate how the quality of accounting disclosure influences market efficiency in the context of stock markets as a keynesian beauty contest, a metaphor first introduced by keynes ( ). at that time, a london newspaper was running a beauty contest in which readers were asked to select a set of six “most beautiful” pictures from photographs of women. whoever picked the most popular pictures was entitled for a raffle prize. to win the competition, players should not naively select six faces they believed the most beautiful; instead, they should use their information to infer which faces other players would believe the prettiest and other players would believe that other players would believe the prettiest and so on. keynes observed that stock markets shared the essence of this competition, in that the actions of many rational but short-horizon investors were similarly governed by their expectations about what other investors believed, rather than by their genuine expectations about the true value of a firm. allen, morris, and shin ( ) rationalize this keynesian-beauty-contest effect as a consequence of investors’ short horizons. since a short-horizon investor exits a firm before its fundamental value is known, her payoff depends on how much other investors would like to pay, rather than on how much she expects the fundamental value of the firm will be. given access to both public and private information, she puts an extra weight on public information due to its dual role. public information plays an information role because it conveys information about the unknown funda- mental value (hereafter the information role); meanwhile, public information plays a commonality role because it is common to the information sets and demand functions of all investors (hereafter the commonality role). although the noise terms in both the public and private signals enter the individual demands of investors, the independent noise terms in the private signals cancel out when the individual demands are aggregated. but the noise in the public signal remains in the aggregate demand because the individual demands share the same noise term. as a result, the public signal influences the price above and beyond its information value. this additional commonality role of pubic information biases stock prices away from the consensus fundamental value toward public information. having qualitatively formalized the keynesian-beauty-contest effect, allen, morris, and shin ( ) also leave many questions open, one of which concerns the market efficiency consequences of disseminating public information in a keynesian-beauty-contest stock market. how does the quality of public information affect market efficiency? how is the intensity of the dual role of public information related to its quality? could the keynesian-beauty-contest effect justify the withdrawal of some noisy public information? these questions are important to accounting researchers. the keynesian-beauty-contest effect provides a new perspective on understanding accounting disclosure. accounting disclosure, as a main source of public information, is a unique feature of public firms characterized by dispersed ownership. understanding accounting disclosure entails examining the consequences of dispersed ownership, among which agency problems and differential information have been the best known. however, dispersed ownership has other consequences that have profound impact on disclosure practice but have not received the attention they deserve. one of such examples is the keynesian- beauty-contest effect. the effect results from investors’ short horizons, which in turn arise because dispersed ownership of modern corporations decouples the life span of entrepreneurs and owners from that of their firms. in the absence of a formal rational interpretation of the keynesian-beauty-contest effect, the extra weight on public information may induce people to speculate that transparency should be curtailed in a keynesian-beauty-contest stock market. as public information becomes noisy, its information value becomes tenuous. if its commonality role increases or at least does not decrease as public information becomes less precise, there could exist a threshold precision under which the diminishing information role is dominated by the non-decreasing commonality role. this kind of conventional wisdom could have immediate prescriptive implications. this paper formally evaluates the market efficiency consequences of disseminating public in- formation in a rational keynesian-beauty-contest stock market. built on allen, morris, and shin ( ), the paper solves for a closed-form equilibrium of a two-trading-period noisy rational ex- pectations model. the comparative statics then show that more public information always drives stock prices closer to the fundamental value, even in the presence of the keynesian-beauty-contest effect. therefore, in a rational competitive market, provisions of more and better accounting dis- closure boost the overall informativeness of stock prices to market participants, and transparency should not be compromised on grounds of the keynesian-beauty-contest effect. prohibition of public information, however noisy it is, amounts to “throwing the baby out with the bathwater”. the rationale for the positive market efficiency effect of public information lies in the endogenous link between the dual role of public information. the information role and the commonality role are connected through the quality of public information. contrary to the conventional wisdom, the commonality role decreases as public information becomes less accurate. that is, when public information becomes noisier, not only do short-horizon investors use it less, they also overuse it less. the intuition is straightforward. the commonality role occurs because short-horizon investors correctly believe in the first place that other investors will be using public information due to its information value. when the information value of public information becomes thinner, investors overuse it less because they again correctly believe that others will be using it less. in the extreme, if a piece of public information is completely useless, it will be neither used nor overused. just as morris and shin ( ) differentiate the keynesian-beauty-contest effect from the sunspot literature based on the fact that public information has the information role, the endogenous link between the dual role of public information is a hallmark of the rational keynesian-beauty-contest effect. the endogenous link between the dual role of public information reconciles this study with morris and shin ( ). assuming that agents have a fixed “beauty contest” component of utility for keeping their actions closer to the average action of others, morris and shin ( ) conclude that noisy public information could be detrimental to social welfare. despite the modeling differences, the discussion in the last two paragraphs suggests that their conclusion may be due to the assumed beauty contest utility, which, by fixing the intensity of the commonality role, divorces the link between the dual role of public information. hence, the comparison of the two studies deepens our knowledge of the keynesian-beauty-contest effect. this paper also contributes to the literature on dynamic noisy rational expectations in capital market by supplying a closed-form equilibrium, which is rare in this literature. this paper is an extension to the work in brown and jennings ( ) and allen, morris, and shin ( ) who conduct only qualitative analysis. besides making it possible to analyze the market efficiency consequences of public information, the closed-form equilibrium opens up many other possibilities. for example, the model could be developed to study firms’ choice between private and public channels to convey information to stock markets. private information is only partially reflected in stock price while grossman ( ), grossman and stiglitz ( ), diamond and verrecchia ( ), and admati ( ) study a single-period noisy rational expectations model; besides allen, morris, and shin ( ), see also brown and jennings ( ) and grundy and mcnichols ( ) for multi-period noisy rational expectations models. anctil, dickhaut, kan- odia, and shapiro ( ),walther ( ) (discussion), and hirota and sunder ( ) conduct interesting laboratory experiments on the keynesian-beauty-contest effect. public information is overused in stock markets. firms may benefit from a balanced combination of both channels. for another example, the relation between information quality and cost of capital has been extensively studied in a single-period model (see easley and o’hara, ; lambert, leuz, and verrecchia, b,a, e.g.). a tractable dynamic model could help reexamine the relation in the context of stock markets as a keynesian beauty contest. in addition, the model may also find applications in the vast erc literature. the rest of the paper is organized as follows. part describes the basic setting of the model; part defines and solves for the equilibrium; part examines the market efficiency consequences of accounting disclosure; and part concludes. the model i describe the basic setting of the model in this section, which closely follows brown and jennings ( ) and allen, morris, and shin ( ). it is a two-trading-period noisy rational expectations economy with short-horizon investors and independent supply shocks. there are two trading periods. a risk free asset and a firm’s risky stocks are traded in both periods in a competitive market. the risk free asset acts as the numeraire of the economy and its return is normalized to be zero. the per share random payoff of the firm’s stocks, denoted as θ, is unknown to investors until the end of the last period. investors’ short horizons are characterized by the overlapping generations assumption. there are two generations of investors and each generation have a continuum of investors indexed by an interval [ , ]. each generation only live in one period and transfer their ownership of the firm to the next generation through trading. young investors are born with endowment and save through the market; at the end of their life period, they become old, sell their stocks and consume the proceeds. for the purpose of this study, i end the overlapping generations cycle at the end of period by the liquidation of the firm. figure describes the time line of events. f igure t he t ime line of events t = p ublic inf ormation is disclosed; y oung investors are born with private inf ormation and wealth; t hey buy stocks in order to resell them at t = . t = a new generation of young investors are born with private inf ormation and wealth; t hey buy stocks in order to liquidate the f irm at t = . t = t he f irm is liquidated and θ is revealed . investors have access to both private and public information, with the later disclosed by the firm. conditional on θ, each investor i in period t receives an independent private signal x̃ti, t ∈ { , } and i ∈ [ , ], with precision β. the realization of the private signal is xti. x̃ti = θ + ǫ̃ti, ǫ̃ti ∼ n ( , β ) ( ) note that the aggregate private information fully reveals the fundamental value, due to the assumption of a competitive market. this design is only for convenience. the general results hold if the pooling of private information is not perfect. we can either use a finite number of investors or assume a common error in investors’ private signals to prevent the pooling of private information from fully revealing the fundamental value. at the beginning of period , the firm discloses an independent public signal, z̃, with precision α. the realization of the public signal is z. z̃ = θ + ǫ̃z, ǫ̃z ∼ n ( , α ) ( ) although the only public information in the model is the firm’s disclosure, the main results still hold if other public information sources are modeled. the linear property of multivariate normal distribution allows other public information to be summarized in α. more other public information indicates a higher lower bound of α. similarly, allowing the firm to disclose another independent signal at the beginning of period does not affect the main results, either. while the firm could make its information public according to a pre-announced disclosure policy, investors can not communicate with each other except through stock price. investors learn about other investors’ private information through stock price. the learning is not perfect because stock prices are contaminated by information irrelevant trading. following the tradition from grossman and stiglitz ( ) and diamond and verrecchia ( ), i use supply noise to summarize all forces other than information that affect stock prices. the random per capita supply noise of the firm’s shares in period t, s̃t, t ∈ { , }, is normally distributed with mean zero and precision γt, respectively. the supply shocks are independent of all signals and of each other. a typical investor, i, has a cara utility function ui(c) = −e − c i τ this paper does not explicitly study choices of the firm’s disclosure policy. however, given the definition of information, the firm’s disclosure policy can be characterized by choosing a parameter α from the interval [ , αmax]. a choice of α = means that the firm does not disclose anything, a choice of α = αmax indicates a policy of disclosing everything the firm knows, and a choice of an interior α is equivalent to a partial disclosure policy by which the firm adds some white noise to its information and discloses the garbled signal. see grossman ( ) and black ( ) for discussions about the nature and source of supply noise. where ci is her consumption financed by selling or liquidating her holdings when she becomes old, and τ is her risk tolerance which is the same across investors. by solving the expected utility maximization problem, we get her demand for stocks, which is linear in information. di = τ (ei[µ̃|ii] − p) v ari[µ̃|ii] ( ) where µ̃ is the random payoff from holding stocks, ei[µ̃|ii] and v ari[µ̃|ii] represent investor i’s estimates of the mean and variance of the random payoff conditional on her information set ii , and p is the stock price. i denote the stock prices in period and using p and p , respectively. note that investors in period expect a payoff of p while investors in period is rewarded by the firm’s fundamental value θ. short horizons induce investors in period to be concerned with the interim price p , rather than the fundamental value θ. for convenience, i also assume that information quality, precisions of supply noise, and investors’ risk tolerance are well defined. that is, α, β, γ , γ and τ are positive and finite. the equilibrium in this section, i characterize the unique linear rational expectations equilibrium of the model in proposition , and compare the closed-form equilibrium with the previous literature. . the equilibrium a rational expectations equilibrium of the short-horizon economy is defined as a pair of prices (p , p ) that satisfies a. the stock market clears in both period and ; b. investors maximize their expected utilities, conditional on all available information, including the information gleaned from stock price; c. investors have rational expectations. their beliefs about all random variables are consistent with the true underlying distributions; d. prices depend on information only through supply and demand. in addition, if (p , p ) are linear functions of information and supply noise, then the equilibrium is a linear rational expectations equilibrium. proposition . there is a unique linear rational expectations equilibrium (p , p ), characterized by p = bz + cθ − ds ( ) p = α + β + ρ + ρ [αz + (β + ρ + ρ )θ − β + ρ ρ ρ βτ s − (β + ρ ) βτ s ] ( ) where b = α α + ρ + βm c = ρ + βm α + ρ + βm d = β + ρ ρ ρ + βm α + ρ + βm βτ m = β + ρ α + β + ρ + ρ ρ = kρ ρ = β τ γ ρ = β τ γ k = ( ρ β + ρ ) all proofs are placed in the appendix. the proof of proposition involves backward induction by solving for p first. the basic idea is to assume a linear price function, plug in the assumed price function to investors’ demand functions, obtain a new price function by equating aggregate demand with aggregate supply, and then compare coefficients of the two price functions to determine the coefficients in the assumed price function. we will focus on p to accentuate the influence of short horizons. in contrast, investors in period receive the liquidation value of the firm. thus, p is only used to terminate the overlapping generations cycle and establish an anchor from which we can apply backward induction to solve for p . unless explicitly noted, from now on, by price i mean p . the commonality role of public information, the extra weight on public information in the price function, and the keynesian-beauty-contest effect of the market are three equivalent concepts. when investors have short horizons, stock prices depend on investors’ expectations of the average expectation of the fundamental value. public information, as common knowledge among investors, plays an additional commonality role of anchoring investors’ beliefs about other investors’ beliefs, causing investors to overuse it. as a result, stock prices have an extra weight on public information relative to private information, and the keynesian-beauty-contest effect occurs. to characterize the keynesian-beauty-contest effect, i use as the benchmark the weight on public information in a long-horizon economy in which the firm’s value is revealed at the end of period . it is a long-horizon economy because investors’ horizons are as long as the firm’s life span. this long-horizon benchmark, characterized in lemma , emphasizes on the fact that the keynesian-beauty-contest effect is attributable to investors’ short horizons. i denote all the variables in this long-horizon case using the same notations with a top “ˆ”. for example, the price in this long-horizon economy is “ p̂ ”. lemma . the long-horizon equilibrium is described by p̂ . p̂ = b̂z + ĉθ − d̂s ( ) where b̂ = α α + β + ρ ĉ = β + ρ α + β + ρ d̂ = βτ β + ρ α + β + ρ ρ = β τ γ allen, morris, and shin ( ) use as the benchmark the consensus fundamental value in the short-horizon economy. the two benchmarks are only slightly different. moreover, the difference does not affect the main results but makes the interpretation easier, as we shall see soon. in addition, allen, morris, and shin ( ) define a long- horizon economy as one in which investors live longer than one period, resulting in difficulty in solving for a close-form equilibrium. note that p̂ differs from p , although both are generated in a long-horizon economy. p is not directly comparable to p because investors in period have additional access to price p which conveys the private information of investors in period . figure summarizes the relation between the short-horizon and long-horizon equilibria by comparing the first-best price pf b, the expected long-horizon price es p̂ , and the expected short- horizon price es p . given the focus on the impact of public information, we use the expected prices with respect to supply noise to get around the confounding effect of supply noise. f igure : t he keynesian beauty contest and the n oise ef f ect ✞ ☎ t he n oise ef f ect ✞ ☎ t he keynesian beauty contest z p ublic inf ormation es p = ē [θ|i ] short − horizon price es p̂ = ē [θ|î ] long − horizon price pf b = θ t he f irst best price ē [·] is the operator of the consensus by taking the average of investors’ expectations in period . since investors learn from different prices in two economies, p and p̂ , î is slightly differ- ent from i , resulting in the difference between two metrics of the consensus fundamental value, ē [θ|i ] = α α+β+ρ z + β+ρ α+β+ρ θ and ē [θ|î ] = α α+β+ρ z + β+ρ α+β+ρ θ. however, because both ρ and ρ are independent of α, using either of them as a benchmark for the extra weight does not qualita- tively affect the main results. thus, for ease of exposition, i omit their difference in the subsequent discussion. pf b is the fundamental value or the first-best price when there are neither supply noise nor short horizons. supply noise prevents the full expression of private information in stock price. this noise effect drives the expected long-horizon price, es p̂ , away from the fundamental value toward public information. one prominent feature of the noise effect is that es p̂ coincides with the consensus fundamental value, ē [θ|î ]. the keynesian-beauty-contest effect is characterized by the further deviation of es p from es p̂ toward public information. the keynesian-beauty- contest effect differs from the noise effect in that es p deviates from the consensus fundamental value, either ē [θ|i ] or ē [θ|î ]. thus, although both the keynesian-beauty-contest effect and the noise effect bias stock prices toward public information, the discrepancy between es p and the consensus fundamental value in the keynesian-beauty-contest effect provides a useful clue to empirically differentiate the two effects. . the comparison with the previous literature having presented the closed-form equilibrium in proposition , i briefly compare the solution of the model with the results in the previous literature on multi-period noisy rational expectations economies with short-horizon investors, mainly brown and jennings ( ) and allen, morris, and shin ( ). this paper is an extension to allen, morris, and shin ( ). they propose that the keynesian- beauty-contest effect could arise rationally from investors’ short horizons, and prove the key results the inability of private information to be fully reflected in stock price resembles the mechanism underlying the rational herding effect in which a subsequent actor can not fully learn her predecessors’ private information because she can only observe their actions but not their private information. in this sense, the noise effect in a noisy rational expectations model is analogous to the rational herding effect, although the later usually concerns only about discrete actions (see bikhchandani, hirshleifer, and welch, , e.g.). in contrast, grundy and mcnichols ( ) study a two-period noisy rational expectations economy in which investors trade in both periods and thus have horizons as long as the firm’s life. they also use a different information structure. without deriving a closed-form solution. built on their paper, i characterize a closed-form equi- librium of their model and identify its implications for the desirability of public information in a keynesian-beauty-contest stock market. papers on a multi-period noisy rational expectations model usually do not derive a closed-form equilibrium. for example, two main papers in this literature, brown and jennings ( ) and allen, morris, and shin ( ), demonstrate their themes based on qualitative characterization. to show their main point that technical analysis has value in a short-horizon economy, brown and jennings ( ) prove the existence of the correlation between the historical price and the fundamental value conditional on the current price. to rationalize the keynesian-beauty-contest effect and demonstrate the role of high-order beliefs in asset pricing, allen, morris, and shin ( ) prove the existence of an extra weight on public information in the price function. there are at least two challenges in characterizing a closed-form equilibrium for a multi-period noisy rational expectations economy. first, investors who can trade multiple times establish extra positions to hedge their demands in later periods. the form of the extra hedging demands is often complicated. brown and jennings ( ) are the first to circumvent this issue by introducing short- horizon investors who only live in one period and have to close their positions at the end of their life. second, learning from stock price under a general correlation structure of noisy supplies across periods is highly non-linear. allen, morris, and shin ( ) assume independent noisy supplies to enhance tractability of their t-period model. i further exploit both features of short horizons and allen, morris, and shin ( ) have also studied a two-period model in the appendix to their paper, as an illustration of the general t-period model in the main text. their price function p is given on page of their paper. with the presence of v ar (p ), v ar (θ) and other non-linear components, the system of the three equations from coefficient comparison at the top of page becomes highly nonlinear, and p is expressed as a function of intermediary variables. independent noisy supplies to solve for the closed-form equilibrium. in particular, the key steps are to focus on deriving the closed-form expressions of the precisions (ρ and ρ ) investors learn from stock prices. with the explicit solution of ρ , we can solve for the explicit expression of p , which is the forecasting target of investors in period . then, we can get the closed-form solutions of ρ and p . to see the evolution from brown and jennings ( ) and allen, morris, and shin ( ) to this paper, we can use the closed-form equilibrium to corroborate their qualitative results. one of the equivalent conditions under which technical analysis has value is that p is not redundant in determining d i, the demand function of some investor i in period . from the proof of proposition in the appendix, d i is given as follows. d i = τ [(α − b c ρ − b c ρ )z + ( c ρ − a c ρ )p + βx i − (α + ρ + β + ( − c )ρ )p ] conditional on z, x i, and p , the incremental weight on the historical price p is not zero because τ ( c ρ − a c ρ ) = βρ(α + β + ρ)(α + β + ρ + ρ )τ (β + ρ )(β + ρ(α + ρ + ρ ) + β( ρ + ρ )) = therefore, technical analysis, or the analysis of historical prices, does have value. furthermore, since we have obtained the closed-form expressions of ρ and ρ , we could also analyze how the quality of public information affects the additional value of historical prices in technical analysis. i leave this topic to future research. we could also use the closed-form equilibrium to confirm the main theme in allen, morris, and shin ( ) that the rational keynesian-beauty-contest effect could arise from investors’ short horizons. the existence of the keynesian-beauty-contest effect is equivalent to b > b̂. that is, there see page of brown and jennings ( ). is an extra weight on public information above and beyond its information value. apparently, b − b̂ = α α + ρ k + βm − α α + ρ + β > since k < and m < . moreover, because we have derived the explicit expressions of b and b̂, we can examine the properties of the keynesian-beauty-contest effect beyond its existence. this paper focuses on one of these other properties: how changes in the quality of public information affect the informativeness of stock prices as signals of the fundamental value. in a keynesian-beauty-contest stock market, the information role of public information makes the stock price a more accurate signal of the fundamental value, whereas the commonality role of public information drives the stock price away from the fundamental value. the overall impact of public information on market efficiency is thus a trade-off between these two opposing forces and the answer is not straightforward. for example, one extreme case is to eliminate the keynesian-beauty-contest effect by prohibiting public information. as α goes to zero, the weight on public information approaches zero in both the long- and short-horizon economies and the keynesian-beauty-contest effect vanishes. in this case, does the withdrawal of public information drive stock prices closer to the fundamental value? while investors put no weight on the noise in the public signal, they are now putting more weight on the supply noise. the net effect of withdrawing some noisy public information is therefore ambiguous. i formally study this issue in the rest of the paper. this is the case because d is decreasing in α. keynesian beauty contest and market efficiency while there are many metrics measuring market efficiency, i focus on price efficiency, the accuracy with which stock prices reflect the fundamental value (see tobin, , e.g). the primary goal of financial reporting is to provide various market participants with information about a business en- terprise’s fundamental value (see fasb, , e.g.). meanwhile, one basic function of markets, stock markets included, is to aggregate and disseminate value relevant information inherently dispersed among market participants (see hayek, , e.g.). to the extent that i examine the impact of the quality of accounting disclosure on the price discovery function of stock markets, price efficiency is a proper measure. by adhering to my definition of market efficiency, i try to avoid unnecessary confusion of terminology. in the theoretical literature on noisy rational expectations in capital markets, price efficiency is sometimes labeled as informational efficiency, as opposed to allocational efficiency based on pareto-efficiency in a general equilibrium (see brunnermeier, , e.g.). the label “informa- tional” is inevitably confused with the empirical definition of market efficiency by fama ( ). moreover, despite the possible divergence, two types of efficiency are closely related. in a much richer model, more accurate prices could enable market participants to make better informed deci- sions with respect to resource allocation. to that extent, price efficiency may also be viewed as a reduced-form counterpart of the pareto-efficiency-based definition of market efficiency, such as the one in grossman ( ). price efficiency is measured using the reciprocal of the mean-squared error (mse) between a firm’s fundamental value and its stock prices, a traditional measure of the extent to which markets hirshleifer ( ) provides an example of the possible divergence. fulfill the price discovery function. in statistical terms, price efficiency emphasizes on the efficiency property of stock prices as an estimator of the fundamental value. lower mse implies that stock prices are much closer to the fundamental value, resulting in higher market efficiency. p e = es,z[p − θ] ( ) pe is an ex ante measure. es,z[·] means that the expectation is taken with respect to both supply noise and public information. given the presence of the keynesian-beauty-contest effect, how could we improve market effi- ciency through accounting disclosure? proposition answers this question. proposition . more public information uniformly improves market efficiency, even in the pres- ence of the keynesian-beauty-contest effect. in the context of stock markets as a keynesian beauty contest, transparency is still a worthwhile cause. accounting disclosure provides information about the future cash flow of a firm. although short-horizon investors overuse it, provisions of more and better financial reporting still boost the overall informativeness of stock prices to market participants. the fact that stock markets behave like a keynesian beauty contest does not justify the withdrawal of public information. public information affects market efficiency through its dual role: the information role and the commonality role. the former improves price efficiency while the later potentially reduces price efficiency. in the absence of a formal examination of the relation between the two roles, we may conjecture that prohibition of some noisy public information may be necessary to enhance market efficiency in a keynesian-beauty-contest stock market. as public information becomes less precise, its information value is attenuated. if the commonality role increases or at least does not decrease in the variance of public information, there could exist a threshold of the precision of public information under which the diminishing information role is dominated by the non-decreasing commonality role. proposition contradicts such a conjecture. it implies that while public information plays the dual role, the information role always dominates the commonality role. since the information role dissipates as public information becomes less precise, a necessary condition for the dominance is that the commonality role decreases in the variance of public information. that is, the dual role of public information is endogenously linked through the quality of public information. i verify this intuition by showing that the keynesian-beauty-contest effect intensifies as public information becomes more accurate. before proceeding to the endogenous link between the dual role of public information, there is one caveat about proposition . the conclusion is obtained in a competitive equilibrium in which the action (demand) of any atomistic investor does not affect the price and thus the ac- tions (demands) of other investors. while this result establishes an important benchmark for the desirability of public information in a competitive market, there could be other channels through which public information reduces the overall informativeness of market prices. in this broad sense, shiller ( ) suggests that news media exert undue influence on market events by promulgating information and thus creating “similar thinking among large groups of people.” one prominent approach, which has been advanced lately and may substantiate shiller’s arguments, is to model explicit coordination motivations among agents. for example, plantin, sapra, and shin ( ) cre- ate explicit coordination issues among financial institutions by introducing the (il)liquidity of the market for selling financial assets. their selling decisions become strategic substitutes under the the august issue of the economist has a concise summary of the main effects in plantin, sapra, and shin regime of historical cost accounting, and strategic complements under the regime of mark-to-market accounting. by coordinating financial institutions’ selling decisions, mark-to-market accounting in- jects “endogenous” and “artificial” volatility to the market price, degrading its information value. thus, the attempt to use the information contained in prices destroys the information value of prices. although they do not model the impact of public information on market efficiency, their approach may be used to construct examples with different conclusions on the desirability of public information. in sum, proposition sets an important benchmark for the welfare effect of public information in a competitive market; it will be interesting to explore what kind of market frictions could change the conclusions in this benchmark case. bearing this caveat in mind, we resume the investigation of the relation between the dual role of public information to gain better intuition behind proposition . as discussed before, the keynesian-beauty-contest effect of stock market, the commonality role of public information, and the extra weight on public information in stock price are three equivalent concepts. using as the benchmark the weight on public information in the long-horizon economy, we could quantify the keynesian-beauty-contest effect as the discrepancy between the weights on public information in p and p̂ . i define the extra weight on public information, r, as follows. r = − b c / b̂ ĉ ( ) since the ratio b c ( b̂ ĉ ) reflects the relative use of public and private information when investors have short (long) horizons, the ratio b c / b̂ ĉ represents the extent to which public information is overused by short-horizon investors. the monotonic transformation in definition normalizes r to ( ). lie between zero and one. the greater r is, the more salient the keynesian-beauty-contest effect. proposition . the keynesian-beauty-contest effect intensifies as public information becomes more precise. since we have solved for the closed-form equilibrium, we can show here the determinant of the intensity of the keynesian-beauty-contest effect. the commonality role is connected to the information role through the quality of public information. when the quality of public information improves, the keynesian-beauty-contest effect becomes more salient and the price concentrates further on public information. the intuition for this link is straightforward. the keynesian- beauty-contest effect occurs because public information has information value in the first place. anticipating that other investors will be using public information to forecast the fundamental value, a short-horizon investor, who tries to forecast the consensus fundamental value, overuses public information over and above its optimal use in assessing the fundamental value. as it becomes more accurate, not only does she use public information more due to its improved information value, she also overuses it further because of its enhanced commonality role of forecasting the consensus fundamental value. just as morris and shin ( ) differentiate the keynesian-beauty-contest effect from the sunspot literature based on the fact that public information has the information role, the endogenous link between the dual role of public information is a hallmark of the rational keynesian-beauty-contest effect. this endogenous link between the information role and the commonality role of public informa- tion is crucial in the market efficiency consequences of public information. short horizons create interdependency of investors’ demands for stocks and give rise to the dual role of public informa- tion. the dual role is endogenously connected to each other in such a way that the commonality role is always secondary to the information role in terms of market efficiency. in contrast, if the dual role of public information is directly assumed, as opposed to being derived from short horizons, the endogenous link is then muted. consequently, when the information value is tenuous while the commonality role is strong enough, noisy public information could decrease market efficiency. morris and shin ( ) prove a similar point. in their game theory model, besides a standard component of utility defined over the distance between her action and the true state, an agent’s loss function has an additional “beauty contest” component with a fixed weight. defined over the distance between her action and the average action across all agents, this assumed “beauty contest” component of utility not only gives rise to the commonality role of public information, but also fixes the intensity of this commonality role. as a result, when the fixed weight is great and public information is noisy enough, the fixed commonality role dominates the diminishing information role and public information becomes detrimental to social welfare, which is defined as the negative of the average mean-squared error between individual action and the true state. the following exercise gives us a glance at the importance of the endogenous link between the dual role of public information. recall that r measures the intensity of the commonality role and that it is increasing in α. now we fix r to be a constant, r, so that the commonality role is decoupled from the information role. observation . when the keynesian-beauty-contest effect is fixed at r, provisions of public infor- mation decrease market efficiency if and only if r and α are such that α < ( − r)(β + ρ )( − (β + ρ ) ρ ( − r)) ( ) and − ρ (β + ρ ) < r < ( ) in the sense that fixing an endogenous variable to a constant inherently has too many degrees of freedom, observation is more a back-of-the-envelope calculation than a rigorous statement. however, it gives some clues about the importance of the endogenous link between the dual role of public information in determining its market efficiency consequences. when the public information is relatively noisy (condition ) and the keynesian-beauty-contest effect is fixed at a high level (condition ), provisions of public information reduce market efficiency. in this sense, conditions and resemble condition in morris and shin ( ). therefore, the comparison of proposition and observation suggests that the detrimental social welfare effect of public information in morris and shin ( ) may result from the assumed “beauty contest” utility, an observation that warrants further investigation. conclusion i study the market efficiency consequences of accounting disclosure in the context of stock markets as a keynesian beauty contest. in such markets, public information performs both an information role and a commonality role. because the dual role of public information is endogenously linked to each other via the quality of public information, disclosure of public information, however noisy it is, always brings stock prices closer to the fundamental value. transparency should not be compromised on grounds of the keynesian-beauty-contest effect. accounting disclosure is a distinct feature of modern corporations characterized by dispersed ownership. previous research on accounting disclosure has mainly focused on agency problems and differential information among investors. this paper provides one example that dispersed ownership has other important consequences for accounting disclosure that have not received the attention they deserve. it opens up many new opportunities for future research. the keynesian- beauty-contest effect may have substantial implications for the trade-off between public and private channels to disclose corporate information, the relation between information quality and cost of capital, and the relation between earnings and stock prices. another promising direction is to include real effects of accounting disclosure so as to exam- ine the allocational efficiency consequences of accounting disclosure in a keynesian-beauty-contest stock market. since allocational efficiency may diverge from market efficiency, such an extension complements this study and deepens our understanding of the real consequences of accounting disclosure in a keynesian-beauty-contest stock market. appendix proof of proposition . i solve for the model in five steps. step : previous work has shown that for an economy in which investors have cara utility functions and the payoff of the security is normally distributed, an investor i’s demand for the risky security is described by equation . step : the information structure in period . assume p = bz + cθ − ds (a- ) for investor i, she interprets p as an independent signal, p ∗ , with precision ρ. p∗ = c (p − bz) = θ − d c s (a- ) ρ = ( c d ) γ (a- ) correspondingly, her information set is i i = (z, p ∗ , x i). notice that p ∗ is the same for all investors although they have differential private information. her belief about the fundamental value θ is characterized by ei[θ|i i] = αz + ρp∗ + βx i α + ρ + β and v ari[θ|i i] = α + ρ + β the estimate of the variance is independent of the realization of signals and thus the same across investors. step : the information structure in period . assume p = a p + b z + c θ − d s (a- ) given the assumption that both z and p∗ are available to investors in period , investor i in period starts with a prior about θ, αz+ρp∗ α+ρ , with a precision of α + ρ. moreover, she also learns from p . given her knowledge about z and p∗ , the independent signal she can extract from p is p ∗ , with precision ρ . p∗ = c (p − a p − b z) = θ − d c s ρ = ( c d ) γ thus her information set is i i = (p ∗ , z, p ∗ , x i). conditional on i i, she forms her belief of θ as follows: ei[θ|i i] = αz + ρp∗ + βx i + ρ p ∗ α + ρ + β + ρ v ari[θ|i i] = α + ρ + β + ρ again the estimate of the variance is independent of the realization of individual investors’ private signals and thus identical across investors. step : solve for p . according to equation , investor i’s demand conditional on i i is d i = τ (ei[θ|i i] − p ) v ari[θ|i i] = τ [αz + ρp∗ + βx i + ρ p ∗ − (α + ρ + β + ρ )p ] = τ [αz + ρ c (p − bz) + βx i + ρ c (p − a p − b z) − (α + ρ + β + ρ )p ] = τ [(α − b c ρ − b c ρ )z + ( c ρ − a c ρ )p + βx i − (α + ρ + β + ( − c )ρ )p ] (a- ) p is determined by aggregating individual investors’ demands and equating it with the aggregate supply. p = (α − b c ρ − b c ρ )z + ( c ρ − a c ρ )p + βx i − s τ (α + ρ + β + ( − c )ρ ) (a- ) the coefficients array (a , b , c , d ) are determined by comparing coefficients in equation a- with those in equation a- . a = c ρ α + ρ + β + ρ , b = α − b c ρ α + ρ + β + ρ , c = β + ρ α + ρ + β + ρ , d = βτ c (a- ) and ρ = β τ γ (a- ) step : solve for p . investor i who purchases stocks in period does not hold them until the firm is liquidated; instead, she resells them at the price of p . her demand, according to equation , is shaped by her expectation about p , which is different from her expectation about θ. in period , investor i’s belief about p is characterized by ei[p |i i] = c ρ α + ρ + β + ρ p + α − b c ρ α + ρ + β + ρ z + β + ρ α + ρ + β + ρ ei[θ|i i] = c ρ α + ρ + β + ρ p + α − b c ρ α + ρ + β + ρ z + β + ρ α + ρ + β + ρ αz + ρp∗ + βx i α + ρ + β = α + ρ + β + ρ [( + β + ρ α + ρ + β )(α − b c ρ)z + β + ρ α + ρ + β βx i + ( + β + ρ α + ρ + β ) c ρp ] and v ari[p |i i] = ( β + ρ α + ρ + β + ρ ) v ari[θ|i i] + ( β + ρ α + ρ + β + ρ ) β τ γ = (β + ρ ) (α + ρ + β + ρ ) (α + ρ + β)ρ her demand is di. di = τ (ei[p |i i] − p ) v ari[p |i i] = τ [ α+ρ+β+ρ (( + β+ρ α+ρ+β )(α − b c ρ)z + β+ρ α+ρ+β βx i + ( + β+ρ α+ρ+β ) c ρp ) − p ] v ari[p |i i] = τ ρ β + ρ [(α − b c ρ) m z + βx i − ((α − b c ρ) m + β)p ] (a- ) where m = + α+ρ+β β+ρ = β + ρ α + ρ + β + ρ (a- ) p is determined by equating aggregate supply with aggregate demand. p = (α − b c ρ) m z + βθ − β+ρ τ ρ s (α − b c ρ) m + β (a- ) the coefficient array (b, c, d) are determined by comparing coefficients in equations a- and a- . b = α α + ρ + βm , c = ρ + βm α + ρ + βm , d = ρ + βm α + ρ + βm β + ρ ρ βτ (a- ) and ρ = ( ρ β + ρ ) β τ γ (a- ) so p is solved for by plugging equation a- to equation a- . p = α α + ρ + βm z + ρ + βm α + ρ + βm θ − β + ρ ρ ρ + βm α + ρ + βm βτ (a- ) p is determined by inserting equation a- and a- to equation a- . p = α + β + ρ + ρ [αz + (β + ρ + ρ )θ − β + ρ ρ ρ βτ s − (β + ρ ) βτ s ] since the coefficients (b, c, d) and (a , b , c , d ) are unique, the linear rational expectations equilibrium in proposition is unique, too. proof of lemma . lemma is proved by using the traditional solution to a single-period noisy rational expectations equilibrium, such as that in diamond and verrecchia ( ). the procedure is the same as that in the proof of proposition , except that ei[p |i i] and v ari[p |i i] in equation a- are replaced by ei[θ|i i] and v ari[θ|i i]. proof of proposition . proposition is proved by showing that the partial derivative of pe with respect to α is positive. define m ′= ∂m ∂α . thus, m ′ = − β+ρ (α+ β+ρ+ρ ) < . p e = es,z(p − θ) = es,z(bǫz − ds ) = b α + d γ = b α + c ρ = ρ(α + ρ + βm ) αρ + (βm + ρ) ∂p e ∂α = ρ(α + βm + ρ)( + βm ′)(αρ + (ρ + βm ) ) − ρ(α + βm + ρ) (ρ + (ρ + βm )βm ′) (αρ + (ρ + βm ) ) = (α + βm + ρ)ρ (αρ + (ρ + βm ) ) [ β m + βm ρ + αρ + ρ − αβ m m ′] > proof of proposition . proposition is proved by showing that the partial derivate of r with respect to α is positive. r = − b c / b̂ ĉ = β( − m ) + ρ ( − k) β + ρ (a- ) ∂r ∂α = − βm ′ β + ρ > proof of observation . observation is proved by showing that the partial derivative of pe with respective to α, evaluated at r = r = β( −m )+ρ ( −k) β+ρ , is negative under condition and . for notational convenience, define b as follows. b = b̂ ĉ = α β + ρ p e = b α + c ρ = c ( b c ) α + ρ = ( − r + b) b α + ( −r) ρ = αρ( − r + b) b ρ + ( − r) α and ∂p e ∂α |r=r= ρ ( − r + b)α (β + ρ ) (( − r) α + b ρ) [α − ( − r)(β + ρ )( − (β + ρ ) ρ ( − r))] (a- ) since α, β, τ , γ , and γ are positive and finite, both m and k lie between zero and one. as a result, < r < . it could be verified that a- < is equivalent to conditions and . references admati, a.r., , a noisy rational expectations equilibrium for multi-asset securities markets, econometrica , – . allen, f., s. morris, and h.s. shin, , beauty contests and iterated 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beauty is not simplicity: an analysis of mathematicians' proof appraisals browse explore more content perspf .pdf ( . kb) beauty is not simplicity: an analysis of mathematicians' proof appraisals citedownload ( . kb)shareembed journal contribution posted on . . , : by matthew inglis, andrew aberdein what do mathematicians mean when they use terms such as 'deep', 'elegant', and 'beautiful'? by applying empirical methods developed by social psychologists, we demonstrate that mathematicians' appraisals of proofs vary on four dimensions: aesthetics, intricacy, utility, and precision. we pay particular attention to mathematical beauty and show that, contrary to the classical view, beauty and simplicity are almost entirely unrelated in mathematics. categories uncategorized philosophy keywords untagged funding this work was supported by a royal society worshipful company of actuaries research fellowship. history school science department mathematics education centre published in philosophia mathematica volume issue pages - citation inglis, m. and aberdein, a., . beauty is not simplicity: an analysis of mathematicians' proof appraisals. philosophia mathematica, ( ), pp. - publisher © oxford university press version am (accepted manuscript) publisher statement this work is made available according to the conditions of the creative commons attribution-noncommercial-noderivatives . international (cc by-nc-nd . ) licence. full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/ . / publication date notes this is a pre-copyedited, author-produced pdf of an article accepted for publication in philosophia mathematica following peer review. the version of record inglis, m. and aberdein, a., . beauty is not simplicity: an analysis of mathematicians' proof appraisals. philosophia mathematica, ( ), pp. - is available online at: http://dx.doi.org/ . /philmat/nku . this paper is closed access until th july . doi https://doi.org/ . /philmat/nku issn - eissn - publisher version http://dx.doi.org/ . /philmat/nku language en administrator link https://repository.lboro.ac.uk/account/articles/ licence cc by-nc-nd . exports select an optionrefworksbibtexref. managerendnotedatacitenlmdc categories uncategorized philosophy keywords untagged licence cc by-nc-nd . exports select an optionrefworksbibtexref. managerendnotedatacitenlmdc hide footeraboutfeaturestoolsblogambassadorscontactfaqprivacy policycookie policyt&csaccessibility statementdisclaimersitemap figshare. credit for all your research. munich personal repec archive does beauty matter in undergraduate education? deryugina, tatyana and shurchkov, olga august online at https://mpra.ub.uni-muenchen.de/ / mpra paper no. , posted feb : utc does beauty matter in undergraduate education? * tatyana deryugina, university of illinois + olga shurchkov, wellesley college ++ abstract: physically attractive individuals achieve greater success in terms of earnings and status than those who are less attractive. however, much about the mechanism behind this “beauty premium” remains unknown. we use a rich dataset to shed light on its nature at the college level. we find that students judged to be more attractive perform significantly worse on standardized tests but, conditional on test scores, are not evaluated more favorably at the point of admission. controlling for test scores, more attractive students receive marginally better grades in some cases. finally, there is substantial beauty-based sorting into areas of study and occupations. * we thank an anonymous college for providing us with student photos and academic records. specifically, we thank the college staff and administration for assistance with acquiring and understanding the data. we also thank jeff brown, kristin butcher, daniel hamermesh, robin mcknight, nolan miller, julian reif, casey rothschild, and akila weerapana for helpful comments. sizhe zhang and mehrnoush shahhosseini provided excellent research assistance. all remaining errors are our own. + department of finance, university of illinois at urbana-champaign, south sixth st., champaign, il, usa. e-mail: deryugin@illinois.edu. phone: - - . ++ department of economics, wellesley college, central st., wellesley, ma, usa. e-mail: olga.shurchkov@wellesley.edu. i. introduction in most settings, discrimination based on characteristics such as gender, age, race, and national origin is illegal. appearance-based discrimination, while not currently unlawful, has been the subject of several lawsuits in recent years. in parallel, the academic literature has documented a positive correlation between earnings and perceived attractiveness for both men and women (hamermesh and biddle, ; biddle and hamermesh, ). however, much about the mechanism behind this “beauty premium” remains unknown, including the extent to which beauty is a signal of innate or acquired ability, the extent of bias in favor of more attractive people, and the extent to which sorting plays a role. in this paper, we use a unique and rich dataset to examine the nature of the beauty premium among students at an all-women’s college. our principal goals are ( ) to test whether attractive students appear more academically capable when they begin college, as measured by their standardized test scores and admission ratings; ( ) to test whether they appear more capable when they graduate, as measured by their gpa; and ( ) to estimate the extent of beauty-based sorting into areas of study and occupations, a potentially important beauty premium mechanism. see for example yanowitz v. l’oreal usa, inc. ( ) and brice v. resch and krueger int’l, inc. (corbett, ). the importance of beauty has been studied in contexts other than the labor market. see, for example, ravina ( ) for the beauty premium in credit markets, andreoni and petrie ( ) for the beauty premium in public goods games, wilson and eckel ( ) for the beauty premium in trust games and berggren et al. ( ) for the beauty premium in electoral outcomes. to achieve these objectives, we estimate the relationships between attractiveness, standardized test scores, course grades, admissions scores, and major/career choices. we find that, even though the admissions committee does not observe applicant appearance, more attractive individuals receive lower scores on the college’s own formula for rating applicants, in this context an important measure of overall applicant quality that reflects a very wide range of student characteristics. this finding is completely explained by the fact that more attractive individuals have lower standardized test scores. specifically, a one standard deviation (s.d) increase in attractiveness is associated with scoring . s.d. lower on the math sat section, . s.d. lower on the verbal sat section, and . s.d. lower on the sat writing section. to our knowledge, our study is the first to find that attractiveness is negatively correlated with ability, as measured by these tests. once we control for math and verbal sat scores, we find no relationship between the college’s admission scores and attractiveness. in addition to showing that more attractive individuals do not appear to be more capable at the beginning of college, the absence of such a relationship implies that the negative correlation between attractiveness and sat scores among admitted students is unlikely to be driven by preferential treatment of attractive students during the admissions process. once we control for sat scores and the admission rating, our results show that more attractive women have a marginally higher overall gpa. we show that this is most likely driven by sorting into types of courses: after controlling for a rich set of course characteristics, our analysis shows no significant relationship between course-level grades and attractiveness, although estimates for some course types are marginally significant. if more attractive people are aware of the beauty premium in the labor market, they may respond by sorting into areas of study or occupations where their attractiveness generates higher returns. indeed, we find that there is substantial beauty-based selection into study areas. specifically, more attractive women are considerably less likely to major in the sciences and much more likely to major in economics. we find no corresponding selection into humanities, other social sciences, or another group of majors that we label “area studies.” overall, we conclude that the beauty premium at the undergraduate level is largely attributable to selection into study areas rather than ability or bias in favor of more attractive students. finally, we estimate the extent of beauty-based selection into various occupational categories. consistent with our results on academic major selection, we find that more attractive women are much more likely to become consultants and managers and much less likely to become scientists and technical workers (including paralegals, technical writers, technicians, and computer programmers). because previous work has shown that earnings vary substantially by major and occupation, this suggests that at least part of the beauty premium in the labor market is explained by major/occupational choice. we contribute to several streams of literature. the first assesses the relationship between attractiveness and ability; it has thus far produced mixed findings. using assortative mating for more on the relationship between earnings and academic major choice, see daymont and andrisani ( ), berger ( ), james et al. ( ), grogger and eide ( ), loury and garman ( ), loury ( ), blundell ( ), bratti and mancini ( ), arcidiacono ( ), kelly et al. ( ), arcidiacono et al.( ), andrews et al. ( ), and wiswal and zafar ( ). arguments and observed facts, kanazawa and kovar ( ) provide indirect evidence suggesting why beauty and intelligence should be positively correlated in humans. satoshi ( ) shows empirically that there is a positive association between iq test results and physical attractiveness in british and american children of both sexes. several studies have also found that body symmetry is positively correlated with cognitive performance (prokosch et al. , bates ). however, in a sample of american men, scholz and sicinski ( ) find no relationship between attractiveness and iq or high school class rank. in a laboratory experiment, mobius and rosenblat ( ) show that more attractive subjects do not perform better in a maze-solving task. in another experimental setting, deryugina and shurchkov ( ) use labor-market- relevant tasks to test for both the existence of a beauty premium and performance differentials between less and more attractive subjects. they find that there is no significant performance differential by attractiveness related to any of the tasks. to our knowledge, our study is the first to consider the relationship between attractiveness and sat scores. although standardized test scores have been shown to be correlated with broad measures of intelligence and cognitive ability (frey and detterman, ; beaujean et al., ; rohde and thompson, ; koenig et al., ), we do not claim to show that more attractive students are less intelligent. more conservatively, our results imply that, even if there is a correlation between attractiveness and fundamental intelligence, it does not translate into higher test scores. to the extent that both intelligence and effort are necessary to score well on standardized tests, it is possible that more attractive people perform worse on body symmetry has been shown to be strongly correlated with attractiveness (see e.g., rhodes et al. , rhodes ). aptitude tests despite being more intelligent. our finding suggests that, if more attractive people are more intelligent, they may invest less time and effort in human capital formation, at least along the dimensions we study (sat scores and gpa). alternatively, more attractive students may expect to be more likely to get into college, conditional on their sat scores, and may therefore rationally exert less effort preparing for standardized tests. although we cannot test expectations directly, we show that more attractive students do not receive higher admissions scores in our data. we also contribute to the broad body of literature on the beauty premium. despite numerous papers on the subject (hamermesh and biddle , biddle and hamermesh , fletcher , ravina , mocan and tekin , berggren et al. , berri et al. , scholz and sicinski , von bose ), much remains to be understood about the beauty premium. in particular, with the exceptions of scholz and sicinski ( ) and von bose ( ), neither its origins nor persistence has been studied. moreover, with the exception of fletcher ( ), the extent to which the beauty premium is driven by differences in ability has not been explicitly estimated. in a sample of high-ability law students, biddle and hamermesh ( ) find that there are no observable skill differences (including lsat scores) between more and less attractive individuals. however, von bose ( ) shows that more attractive teenagers receive higher high school gpas than less attractive ones. our findings do not definitively resolve whether more attractive individuals are more capable of academic achievement; while more attractive students perform worse on standardized tests, they are not viewed more or less favorably by admissions officers overall and at best earn marginally higher grades than their less attractive peers. however, we find strong support for another hypothesis about the beauty premium mechanism: sorting. the policy implications of our findings hinge on whether the observed sorting is efficient. it would be efficient, for example, if more attractive students are selecting into certain majors and occupations because of productivity expectations. if, on the other hand, the sorting is due to attractive students’ anticipating a pro-beauty bias in some professions then it may not be optimal from a social point of view. this line of inquiry falls outside the scope of this paper. however, it is worthwhile to note that even if the observed sorting is not socially optimal, policies designed to prevent it would most likely be impracticable. the rest of the paper is organized as follows. section ii describes our sample and data. section iii outlines the empirical strategy. section iv presents and discusses the findings. section v concludes. ii. data our dataset consists of alumnae who graduated from an anonymous women’s college between the years and . to measure attractiveness, we use pictures taken when the alumnae were first-year students. a key advantage of our data is that the pictures are not chosen by the student: all are photographed for their student id cards by campus officials. the pictures were subsequently rated by current male and female students from a college in another state. this study was conducted with irb approval. individuals had to consent to have their photographs included in the study. about , alumnae were contacted for consent. informed consent form and description of the project sent to the alumnae are available upon request. each picture was rated by at least male and female raters. we then demean the ratings to remove rater fixed effects and average them to obtain the mean attractiveness rating of each alumna. due to the large number of alumnae, not every picture was rated by the same set of raters. for additional details about the rating procedure, see appendix a. the attractiveness rating is then matched to the alumna’s academic record, which includes her major, sat scores, course-level grades, race, non-merit-based financial aid awards, international status, and scores from a quantitative reasoning (qr) test that all first-year students are required to take. like the sat, the qr test is scored blindly, without observing the test- taker’s appearance. moreover, we observe each student’s admission rating, as assigned by three or more application reviewers. with few exceptions, application reviewers do not observe the student’s appearance. at the request of the college, we use a non-disclosed linear transformation to disguise the true rating scale. finally, we have detailed characteristics for each course, including department, course level (introductory, intermediate, or advanced), total enrollment, and the gender of the instructor. starting in the fall semester of , the college implemented an anti-grade-inflation policy that capped the average grade in introductory and intermediate courses with ten or more some international applicants have toefl scores that are accompanied by a picture. in some cases, applicants are interviewed by a member of the admissions staff or by an alumna. however, the application reviewers have access only to the interviewer’s comments, which do not contain information about the applicant’s appearance. students to a b+. this policy change disproportionately affected humanities courses. if there is beauty-based selection into humanities courses, this policy change may bias our estimates. to control for the potential impacts of the anti-grade inflation policy, we identify departments that had average grades exceeding a b+ and label beginning and intermediate courses with more than ten students in those departments as “treated.” we then control for the treated indicator and its interaction with a “post-fall-semester- ” indicator in all course-level regressions. to create our course-level controls and test for sorting, we classify the courses and majors offered at the college into six categories: humanities, sciences, social sciences, area studies, economics, and other. to do this, we use a publication provided by the college, which classifies courses and majors into “humanities,” “social sciences,” “science and mathematics,” and “interdepartmental programs.” because the “interdepartmental programs” category contains a significant share of the majors, we reclassify some of them into the first three categories. in addition, we classify majors such as “south asia studies” and “german studies,” which are originally listed as interdepartmental into a new “area studies” category. we place economics in its own category because the college does not have a separate business major. thus, the students who elect to study economics may be different from students choosing other social sciences as their major. the courses and majors that do not fit into any of the above categories are classified as “other.” see appendix b for the exact classification. finally, data on occupations come from alumnae surveys and are available for slightly over half of the alumnae in our sample. we categorize occupations into ten broad categories: the full impact of the anti-grade-inflation policy has been analyzed by butcher, mcewan, and weerapana ( ). consultant/manager, administrator, art/advertising, teacher, technical, scientist, lawyer, doctor, other medical, and non-profit/government. in a few cases, the categories overlap: someone who is working in an administrative position in a non-profit would be placed in both categories, for example. there are a few alumnae reporting occupations that cannot be classified into one or more of these categories, because the occupation descriptions are either vague or very unique. although we cannot list the specific occupations due to confidentiality concerns, we provide a general list of occupations in each category in appendix b. our data are not without limitations. first, we do not observe parental income, a potentially important control. however, we do observe the amount of need-based and non-need- based loans and grants that a student receives, which we use as a proxy for parental income. we also do not observe post-college earnings. thus, we cannot test whether more attractive students in our sample also end up earning a higher salary. table presents summary statistics for the key variables in the data, broken down by whether individuals are below or above the median attractiveness rating of - . . the attractiveness rating itself ranges from - . to . and has a mean of by construction. the admissions ratings range from to , with higher ratings corresponding to a higher chance of admission. the average gpa in the sample is fairly high, ranging from . in economics to . in area studies. on average, % of the students pass the quantitative reasoning test, which is scored out of points. the average grant amount is about $ , . need-based and other loans are substantially smaller, averaging around $ , and $ , respectively. there are some significant differences between those who are above and those who are below the median attractiveness rating. more attractive students are more likely to be hispanic/latina and have about $ more in non-need-based loans. they score significantly lower on the math, verbal, and writing sections of the sat as well as on the qr test. in addition, more attractive students have lower admissions ratings, on average. finally, there are no significant differences between the two groups in terms of gpa, need-based loans and grants, or other racial categories. we later perform a formal regression analysis to test whether the differences in test scores and admissions ratings hold once controls for student characteristics are included. one potential concern is that the sample of women who consented to participate in our study may not represent all students at the college. to test for this, we compare the mean test scores, admissions ratings, and year of enrollment for the entire population of alumnae who graduated between and with those of the consenting group. the results are shown in table . overall, the consenting students have significantly higher test scores and admission ratings. they also enrolled in the college about half a year later than the general population of students, on average. because of the necessity to obtain informed consent, we cannot do anything to correct for this or test whether there is beauty-based selection. however, as long as there is no selection on the relationship between attractiveness and other outcomes, such as test scores and gpa, our analysis is valid despite the baseline differences. while we view such selection as highly unlikely, we recognize that the validity of our analysis relies on the assumption that it did not occur. we also note that the college from which we obtain data is fairly selective, as evidenced by the high average sat scores of admitted students (see table ). thus, our study complements some earlier work such as fletcher ( ), who focuses on individuals with high school diplomas only. a final concern is that, because our sample comes from a women’s college, it may not be representative of colleges as a whole. again, this would bias our results only if the beauty premium varies by college. the college from which we obtain our data draws from a pool of students and faculty similar to those of other top-tier universities and liberal arts colleges. we do not see any obvious model of sorting that would cast doubt on the generalizability of our results. moreover, our focus on women complements some earlier work that looks exclusively at men (e.g., biddle and hamermesh ; scholz and sicinski ). finally, the prior literature has found that the beauty premium exists for both men and women and is similar in magnitude. however, replicating the study in a co-educational setting should be an important validation exercise. iii. empirical framework conceptually, we might expect a positive correlation between attractiveness and academic success or, more generally, between attractiveness and some outcome of interest, for several reasons. first, attractiveness may be correlated with a particular characteristic, such as intelligence, trustworthiness, or confidence. if this characteristic is unobserved or poorly measured, omitted variable bias will result, creating a spurious correlation between beauty and the outcome of interest. in the context of academic success, if more attractive people are also more intelligent, then controlling for intelligence is crucial for isolating the effect of attractiveness itself. second, attractiveness may itself be productive in some settings. for example, more attractive solicitors may bring in more donations, justifying paying them a higher salary (landry et al. ). this mechanism is less likely to apply in a college setting, however. finally, people may be biased in favor of more attractive individuals, conditional on their characteristics and productivity. if more attractive people are aware of these channels, they may respond by exerting greater effort into their academic work and preparing for relevant tests or sorting into occupations where their attractiveness or other characteristics is more productive. unfortunately, effort in such a context is rarely readily observable. however, the richness of our data allows us to test for beauty-based sorting into both areas of study and occupations. in addition, we estimate the relationships between beauty, aptitude test scores, and course grades to shed light on the other channels through which attractiveness may operate. in theory, it is possible that a portion of attractiveness can be explained by investment rather than inherent beauty. to our knowledge, there is little work addressing the potential endogeneity of beauty and virtually no work in this area is able to fully eliminate such endogeneity concerns. we control for race and financial aid in all our regressions, which should eliminate some of the components of beauty that may be correlated with socioeconomic characteristics and thus a student’s ability to invest in appearing more attractive. our results are very robust to excluding these controls, and our summary statistics suggest that beauty is not strongly correlated with most of these characteristics. we first estimate the relationship between the attractiveness rating and admission scores. because the admissions committee does not observe applicant appearance directly, any one paper that explicitly considers investment in attractiveness is hamermesh et al. ( ), who find that there is a positive relationship between attractiveness and spending on clothing and cosmetics. correlation between attractiveness and the admission rating will be due to more attractive students differing in the quality of their recommendation letters, extracurricular activities, personal essays, and other application characteristics. 𝐴𝑑𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠𝑖 = 𝛼𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝑋𝑖′𝛾 + 𝜀𝑖 ( ) where 𝑖 represents the individual alumna and 𝐴𝑑𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠𝑖 is the average admission score assigned to her by three or more raters. the variable 𝑅𝑎𝑡𝑖𝑛𝑔𝑖 is the alumna’s attractiveness rating, and 𝑋𝑖 is a vector of student characteristics, including math and verbal sat scores, a set of race indicators, the logs of grant and loan amounts, and year-of-enrollment fixed effects. we add to the grant and loan amounts prior to taking their logs to avoid missing observations. our results are generally robust to the exclusion of controls for financial aid and race, however. in a related specification, we allow the coefficient on the attractiveness rating to vary by attractiveness quintile to test for non-linear effects. we then estimate the relationship between attractiveness and gpa, controlling for standardized test scores, the admissions rating, and student characteristics. 𝐺𝑃𝐴𝑖 = 𝛽𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝑋𝑖′𝛾 + 𝜀𝑖 ( ) where 𝐺𝑃𝐴𝑖 is the student’s grade point average on a – scale. in this case, 𝛽 may be capturing the effect of bias, sorting, or skill differences that are correlated with attractiveness but are not adequately controlled for by our ability measures. in theory, 𝛽 may also be capturing direct productivity differences associated with attractiveness itself (e.g., a more attractive model or actor may earn more money because her attractiveness is more productive). however, we think direct productivity differences are highly unlikely to be present in a college setting. in order to remove the influence of some of these factors, we also estimate the relationship between attractiveness and course-level grades. specifically, we include a rich set of course-level controls to eliminate any beauty premium driven by differential course choices. 𝐺𝑟𝑎𝑑𝑒𝑖𝑗𝑡 = 𝛽𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝐴𝑏𝑖𝑙𝑖𝑡𝑦𝑖′𝛿 + 𝑋𝑖′𝜌 + 𝑍𝑗′𝛾 + 𝜃𝑑 + 𝜇𝑎𝑡 + 𝜋𝑇𝑑 + 𝜎𝑇𝑑𝑃𝑡 + 𝜀𝑖𝑗𝑡 ( ) where 𝑖 indexes individuals, j indexes courses, and t indexes semesters. the variable 𝐺𝑟𝑎𝑑𝑒𝑖𝑗𝑡 is the course grade, measured on a – scale. the vector 𝑍𝑗 is a set of course-level characteristics, namely the gender of the instructor, total enrollment (in logs), and whether the course is a beginning, intermediate, or advanced course. finally, 𝜃𝑑 is a set of department fixed effects (e.g., english, mathematics, physics), and 𝜇𝑎𝑡 denotes course-area-by-semester fixed effects (e.g., humanities in fall , sciences in spring ). the variable 𝑇𝑑 indicates whether the department had a grade average exceeding a b+ prior to the implementation of the anti-grade-inflation policy and 𝑃𝑡 is equal to one for the fall semester of and later. standard errors in this specification are clustered by student. finally, we estimate the amount of beauty-based sorting into distinct fields of study, using a probit specification. 𝐼[𝑀𝑎𝑗𝑜𝑟 = 𝑀]𝑖 = 𝛽𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝑋𝑖′𝛾 + 𝜀𝑖 ( ) where 𝐼[𝑀𝑎𝑗𝑜𝑟 = 𝑀]𝑖 is an indicator equal to if a student 𝑖 is majoring in area m and otherwise. we estimate this relationship separately for five areas of study: humanities, sciences, social sciences, economics, and area studies. the classification of majors into these five areas is detailed in appendix b. we estimate an analogous equation for career choices. fall semesters in two different years are treated as different semesters. iv. results i. admission ratings and test scores our first line of inquiry is to test whether attractiveness is correlated with the admission rating of the student. this test addresses the important question as to whether more attractive applicants differ from less attractive ones prior to college attendance, at least in our sample. although the admissions committee does not observe everything about the applicant, the applications contain much more information than is available in our data, including extracurricular activities, recommendation letters, and personal essays. through these, it is possible that the admissions committee receives signals about other skills that predict college success and that may be correlated with attractiveness. because the admission rating is assigned without observing the student’s appearance, any correlation between the two will be due to beauty-based differences in application characteristics, such as those listed above, rather than bias. the results of this analysis are shown in table . all specifications include controls for the year of enrollment, the student’s race, and logs of financial aid amounts by category (need-based loans, other loans, and grants), with ’s added to avoid missing values. although the admission ratings of more attractive students are worse on average (column ), we find that this is entirely driven by sat scores. once we control for math and verbal sat scores (column ), there is no relationship between the admission rating and attractiveness. we do not control for the sat writing section score because it was not offered until , and including it would significantly reduce our sample size. the non-linear specification in column shows that the lower admission rating of more attractive applicants is driven mainly by those in the top quintile of attractiveness. however, this difference also disappears once we control for sat test scores (column ). using the estimates in column , we can reject a very small beauty premium of . or larger in admissions ratings with % confidence, which is equivalent to about . % of the mean admission rating. table rules out the possibility that attractiveness is correlated (on net) with characteristics that admissions officers can observe but we cannot. it also provides evidence that more attractive applicants are not more likely to get into college, all else remaining equal. in fact, if we do not condition on sat scores, more attractive applicants seem less likely to be admitted. the fact that more attractive applicants have worse application packages could be driven by differential ability, effort, or both. if effort is a factor, then test scores and other components of the college application, such as personal essays and extracurricular activities, are endogenously determined. as we discuss in more detail below, if effort is costly and the outside options of more attractive individuals are superior, it is possible that they will expend less effort on college preparation, even if their ability is equal to or exceeds that of their less attractive peers. one potential concern with the results in table is that it is conditional on being admitted to the college. while we do not observe the admission ratings of applicants who were not admitted, it is highly implausible that more attractive applicants are more likely to be admitted but do not have higher admission ratings conditional on getting in, for several reasons. first, the college that provided the data does not have a strict numeric cutoff for admissions. the density of admission ratings in our sample, shown in figure , confirms this. the distribution looks smooth, with no apparent discontinuity. in order for more attractive applicants to be more likely to be admitted in our case, attractiveness would have to increase the chances of the applicant’s being admitted conditional on her rating, also implying that the marginal and infra-marginal applicants would have to significantly differ from each other. second, because the admissions committee does not observe the applicant’s appearance, it is unlikely that appearance has an effect separate from the admission rating. third, we find no significant relationship between attractiveness and the admission rating when we look at students with above-median or below-median admission ratings. in addition, we explicitly test whether attractiveness moderates the importance of test scores by interacting test scores with the attractiveness rating and find that it does not. the summary statistics in table along with the results in table suggest that more attractive students perform worse on standardized tests. to test this directly, we estimate the relationship between (a) sat and qr scores and (b) attractiveness. because these tests are scored blindly, there is no concern that examiners are discriminating against or in favor of more attractive people. in other words, it is clear that attractiveness does not directly cause a higher test score in this case. rather, any correlation between test scores and attractiveness will reflect some unobserved (to us) variable, such as intelligence or effort. the results are shown in table . columns , , , and show the results of considering a simple linear relationship between attractiveness and test scores. a one s.d. increase in factors that may affect the chance of admission conditional on the admission rating include race, the applicant’s place of residence (e.g., massachusetts versus nebraska), high school quality, parental income, whether the student is the first to go to college in her family, and legacy status, among others. results are available upon request. attractiveness is associated with a . s.d. decrease in the individual’s math sat score, a . s.d. decrease in the verbal score, and a . s.d. decrease in the writing score. finally, more attractive students also score about . s.d. lower on the first-year qr score. these results are very robust to varying the set of included controls. in columns , , , and , we show the results of allowing the relationship between attractiveness and test scores to vary by attractiveness quintile. for the math sat section (column ), there is a sharp and significant drop in scores only for the top attractiveness quintile: the most attractive students score about . s.d. lower than the least attractive students. the same pattern holds for the qr test (column ). for the verbal section of the sat, the drop is more gradual, with students in the rd , th , and th quintiles performing significantly and progressively worse than students in the bottom quintile. the most attractive students score about . s.d. lower than the least attractive students. finally, we cannot detect any differences by quintile on the writing section of the sat. a potential objection to these results is that our sample consists of people who have been admitted to the college. if more attractive students have characteristics other than sat scores that are more likely to result in their being admitted, this would lead to a mechanical negative correlation between sat scores and attractiveness among the sample of admitted women. however, as we demonstrate in table , the admission scores of more attractive students are not higher, providing strong evidence against their being more likely to be admitted. moreover, restricting the sample to students with below-median admission ratings does not substantively change our results. thus, our finding of a negative correlation between attractiveness and sat scores is unlikely to be driven by this type of selection. to our knowledge, the finding that more attractive people perform worse on standardized tests is new and adds nuance to the hypothesis that more attractive individuals earn more because of some unobservable skill, such as intelligence. in contrast to our results, previous work has found that more attractive individuals attain either equal or higher test scores relative to their less attractive peers. however, with the exception of biddle and hamermesh ( ), who estimate the relationship between men’s looks and lsat scores, previous papers have used tests that aim to measure fundamental intelligence, such as iq tests. sat scores, on the other hand, are likely determined by some inherent skill and by effort, which may explain the difference between our findings and previous work. if more attractive individuals generally expect to receive preferential treatment in life or have better outside options for other reasons, they may rationally choose to exert less effort in advancing their credentials, all else remaining equal. although some of the previous work on beauty has considered beauty-driven selection, none has considered differential investment in human capital. separating differential investment from ability is beyond the scope of our data. however, our results highlight an important possibility: even if intelligence and attractiveness are positively correlated, the ability of individuals to modify their effort level may counteract or even reverse the relationship between outcomes and beauty in settings where effort matters. ii. grades the estimates in tables and demonstrate that more attractive students do not begin college with better credentials. if anything, more attractive students have lower admission ratings, driven by their lower sat scores. in addition, they subsequently score worse on a first- year qr test. a natural follow-up question is whether more attractive students end up performing better in college than their less attractive counterparts. in other words, is there evidence that the beauty advantage develops during college? we should note right away that such better performance could occur for a number of reasons: skill, bias on behalf of instructors or classmates, endogenous effort, and selection. we try to directly assess some of these factors below. throughout the analysis, we use the math and verbal sat scores as well as the admission rating as ability controls. again, we do not control for the writing sat score because it was not offered until , and including it would have significantly reduced our sample size. the benefit of including the admission rating is that it captures a broader range of skills than sat scores and it appears unaffected by attractiveness. however, our results are unchanged if we omit the admission rating from the set of controls. table shows the relationship between attractiveness and gpa, with and without controlling for test scores and the admission rating. we consider both first-year and overall gpa. while the latter is a better reflection of overall student performance, the former might be more relevant for our attractiveness measure, which reflects student appearance in their first year. our results are also generally robust to including state of high school/international student fixed effects and to not controlling for the anti-grade-inflation policy. a full set of estimates is available upon request. although we allow for the possibility that our attractiveness measure is specific to the first year, von bose ( ) finds that attractiveness is highly correlated within an individual over time. overall, there is no significant relationship between a student’s attractiveness rating and her first-year gpa, although the quintile specifications indicate that students in the second quintile have marginally lower gpas than students in the first quintile. even though the estimated beauty premium in column is significantly different from zero, the significance level is marginal and the magnitude is not large. the % upper bound for this estimate is . points or about % of the mean gpa per one standard deviation of attractiveness. the admission rating is highly predictive of gpa, demonstrating that it is a useful measure of ex-ante student ability. we next examine whether there is heterogeneity by area of study. specifically, we consider gpa separately for five major study areas: sciences, social sciences, humanities, area studies, and economics. there may be less room for instructor discretion in the sciences. thus, any difference in gpa in this area is more likely to reflect performance differences or selection rather than instructor bias. in addition, more attractive students may select into study areas in which they have a comparative advantage. table shows the results. more attractive students have a marginally higher gpa in the sciences, but there is no significant difference between more and less attractive students in any of the other study areas. however, the standard errors on the point estimates are fairly large, and we cannot rule out the possibility that the point estimates in all five areas of study are equal to each other. we next consider the relationship between course-level grades and attractiveness. because of the detailed nature of the course-level data, we are able to include many controls to eliminate the selection channel, such as course type (humanities, sciences, social sciences, area studies, for a discussion of how we classify majors and courses into study areas, see appendix b. economics, and other) and department (e.g., math, french, english). we also include course- type-by-semester fixed effects, year-of-enrollment fixed effects, race fixed effects, and financial aid amounts as controls. standard errors are clustered at the student level. the results are shown in table and indicate that there is no significant correlation between attractiveness and course-level grades. the point estimates are positive and similar in magnitude to those shown in table . the inclusion of sat scores and admissions ratings increases the magnitude of our point estimates, but they remain statistically insignificant. the results are robust to excluding the course-level controls listed above, to not controlling for the anti-grade- inflation policy, and to using only qr test scores or admission ratings as ability controls. we next test for heterogeneity in the beauty premium between small and large courses and between male and female instructors. we use two measures of course size—an indicator for below- and above-median enrollment ( or fewer v. or more students) and indicators for enrollment size quartiles. we might expect males to be more responsive to female attractiveness than females (e.g., landry et al. ). we might also expect the beauty premium to be larger in smaller courses because the appearance of individual students is easier to observe. including course fixed effects in the course-level regressions does not alter our results. however, due to the small number of observations per course (mean of , median of ), we do not use course fixed effects in our preferred specification. for space reasons, we do not show these specifications. results are available upon request. note that “large” courses have students enrolled on average, with students being the largest class size in our sample. the results are shown in table . overall, it appears that there is a modest and marginally significant beauty premium in courses taught by female instructors and in courses with above- median enrollment. there is also a marginally significant beauty premium in the smallest course size quartile ( students or fewer), with more attractive students receiving grades that are . points higher. however, as the p-values from the test of equality show, we cannot reject the hypothesis that the rating coefficients in each specification are equal to each other. moreover, the point estimate for courses with below-median enrollment is actually larger than that for courses with above-median enrollment. overall, we find little evidence for a meaningful beauty advantage for college grades: while more attractive women have a marginally higher gpa overall, they do not receive significantly higher grades once we control for a rich set of course characteristics. there is also some evidence of a marginal beauty premium in small courses and in courses taught by female instructors, but we cannot rule out the null hypothesis of no heterogeneity in these course characteristics. our interpretation of these results is that the role of attractiveness in college grades is small and economically insignificant. iii. sorting more attractive students do not begin college with better credentials than their less attractive peers. they appear to earn marginally better grades during college, all else remaining equal, but the differences largely disappear once we introduce extensive course-level controls. this suggests that there may be some beauty-based selection, another channel through which the beauty premium may occur if more attractive people specialize in areas in which they have a comparative advantage. our final goal then is to explicitly assess whether more attractive students make systematically different choices in terms of course and major selection. first, we consider the propensity of more attractive students to take courses in five main subject areas: humanities, social sciences, science, area studies, and economics. the dependent variable is the percent of courses taken by the student in that particular subject area. the results are shown in table . conditional on their test scores and admission ratings, more attractive students take . percentage points more economics courses and . percentage points fewer science courses. there is no selection into other social sciences, humanities, or area studies courses. the pattern of selection by attractiveness quintile suggests that the most attractive women select out of science courses and into economics courses almost one-for-one: women in the fourth and fifth quintile of attractiveness take . and . percentage points fewer science courses, respectively, and . and . more economics courses, respectively, than the least attractive women. thus, there is substantial beauty-based selection into course areas. a natural follow-up question is whether more attractive students are also less likely to major in sciences and more likely to major in economics. we investigate this sorting hypothesis by regressing an indicator variable for whether the student is in a particular major on her attractiveness rating and various controls, using a probit specification. some students have multiple majors and may thus appear in multiple categories. the results are shown in table . the estimated coefficients have been scaled by to make them easier to read. as expected given the results in table , more attractive students are significantly less likely to major in the sciences and significantly more likely to major in economics. the marginal effects at the mean indicate that a one s.d. increase in attractiveness is associated with a . % decrease in the probability of majoring in science and a . % increase in the probability of majoring in economics. there is no significant selection into humanities, other social sciences, or area studies majors. other majors that make up a significant fraction of the sample, namely psychology, english, and political science, likewise show no beauty-based selection (results not shown). the selection out of the sciences and into economics is again driven by the top two quintiles of attractive women, although the likelihoods appear to change monotonically with the quintile. finally, we test for beauty-based sorting into occupations, using a probit model. the estimated coefficients, scaled by , are shown in table . because occupation choice occurs shortly before or after final gpa is known, we include it as a control. however, our results are robust to not controlling for gpa. we find that more attractive women are much more likely to become consultants or managers and much less likely to enter technical or scientific fields. specifically, a one s.d. increase in attractiveness is associated with a . % increase in the probability of becoming a consultant or manager and a . % decrease in the probability of becoming a scientist or a technician. this is consistent with our earlier results on major choice. there is no significant beauty-based selection into administrative fields, art and advertising, or teaching. similarly, we find no selection into the medical or legal professions or into non-profit/government jobs (results our results are robust to considering “consultant” and “manager” separately, combining “lawyer” and “doctor,” combining “doctor” and “other medical,” and considering “art” and “advertising” separately. not shown). although we lack occupation information for almost half of the alumnae in our sample, the fact that these findings mirror those in tables and makes us more certain that they are not driven by selective reporting. moreover, the response rate in our data is similar to (and, if anything, slightly higher than) the response rate of the alumnae pool from which we draw our sample. it is worth considering whether our findings translate into earnings. although we cannot examine the relationship between earnings and attractiveness directly, we can refer to prior literature. there is some evidence that sat scores are positively correlated with post-college earnings (dale and krueger ), as is college gpa (loury , arcidiacono , hershbein ). because none of these papers considers attractiveness specifically and many restrict their sample to men, we are hesitant to argue that they extend to our setting. there is however more evidence available on the relationship between earnings and choice of college major. the existence of earnings differentials across majors is well- documented (see, e.g., daymont and andrisani , grogger and eide , loury , and arcidiacono ). overall, researchers find that students majoring in fields such as business/economics, science, and engineering generally earn more than those majoring in humanities, education, and other social sciences. these differences persist even after controlling for selection on observables (andrews et al., ). because we find that more attractive women are less likely to major in sciences but more likely to major in economics, this previous research has ambiguous implications for our findings. hershbein ( ) finds that this relationship holds only for less selective colleges. in experimental settings, both arcidiacono et al. ( ) and wiswal and zafar ( ) show that students’ perceptions of expected earnings and ability are significant predictors of major choice. likewise, berger ( ) finds that individuals choose majors that they perceive as being more likely to provide a larger stream of earnings. thus, it is likely that some of the beauty-based selection in our sample is driven by earnings expectations. alternatively, differential preferences could be driving the observed sorting in our data. for example, if more attractive individuals are also more extroverted, they may prefer to enter jobs where they are more likely to work with others, even if this does not result in higher wages. to our knowledge, however, there is no work showing the existence of a correlation between attractiveness and personality traits that would lead a more attractive person to choose one career over another, all else (including wages) remaining equal. v. conclusion the issue of beauty-based discrimination has gained increasing attention in recent years. prior literature has found that more attractive people earn more on average. however, much remains unknown about the origins and evolution of the beauty premium, including whether there are differences in academic capability between more and less attractive individuals, and the extent of bias and sorting that occurs. we contribute to the literature by considering whether there is a beauty advantage before and during college and by estimating the extent to which beauty-based sorting occurs. we find that more attractive women do not appear more academically capable at the point of college admissions. on the contrary, they receive lower admission ratings, even though the application readers never directly observe applicant appearance. this is because more attractive women receive lower sat scores. although previous researchers have found that standardized test scores are positively correlated with measures of cognitive ability (see, e.g., frey and detterman , beaujean et al. , rohde and thompson , and koenig et al. ), these findings do not necessarily contradict earlier findings that more attractive people have higher iqs. sat scores are likely to be a function of both innate ability and effort. it may be that more attractive people rationally exert less effort on the sat because the other advantages available to them make it optimal to invest fewer resources into scoring higher on the sats. testing this hypothesis is beyond the scope of this paper, but should be a worthwhile avenue for future research. we find substantial beauty-based sorting into areas of study, with more attractive women being significantly less likely to major in the sciences and much more likely to major in economics. they are also subsequently less likely to work in science-related or technical fields and more likely to become consultants, analysts, or managers. overall, our findings show that the main difference between more and less attractive people during college appears to lie not in the grades they receive but rather in the major and career choices they make. unfortunately, we cannot determine whether the observed sorting into majors is socially optimal, which is important for estimating welfare effects and deriving policy implications. however, even if inefficient sorting is present, policy tools capable of addressing it would be controversial and perhaps impossible to implement. the results suggest several directions for future research. first, reproducing the analysis with a mixed-gender group of college graduates would enhance our understanding of gender differences in the role of appearance in undergraduate education. second, studying more post- graduation outcomes, such as labor force status, earnings, and history of promotions would shed light on how the beauty premium for college graduates evolves later, after they have entered the labor market. figures and tables . . . k e rn e l d e n s it y admissions rating figure . density plot of admissions ratings table : summary statistics above-median attractiveness rating below-median attractiveness rating mean std. dev. min max obs mean std. dev. min max obs attractiveness rating . *** . - . . - . . - . - . admission rating . *** . . . . total gpa . . . . . . . humanities gpa . . . . . . social science gpa . . . . . . science gpa . . . . . . area studies gpa . . . . . . economics gpa . . . . . . math sat score *** verbal sat score *** writing sat score * qr test score . * . . . . passed qr test . . . . asian . . . . black . . . . white . . . . hispanic . ** . . . latina . ** . . . need-based loans ($) , , , , , , grants ($) , , , , other loans ($) ** , , , , stars indicate significant differences in means from the “below-median” group. significance levels: * percent, ** percent, *** percent. social science gpa excludes economics. table : difference between the general student population and those giving consent ( ) ( ) ( ) ( ) ( ) ( ) math sat verbal sat writing sat qr test score admission rating year enrolled all students . . consenting minus all . *** . *** . *** . *** . *** . *** observations , , , , , , significance levels: * percent, ** percent, *** percent. table : attractiveness and admission ratings ( ) ( ) ( ) ( ) attractiveness rating - . *** - . ( . ) ( . ) attractiveness quintile = . . ( . ) ( . ) attractiveness quintile = . . ( . ) ( . ) attractiveness quintile = - . - . ( . ) ( . ) top attractiveness quintile - . *** - . ( . ) ( . ) math sat score . *** . *** ( . ) ( . ) verbal sat score . *** . *** ( . ) ( . ) dep. var. mean . . . . observations r-squared . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include year of enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : attractiveness and test scores ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) math sat verbal sat writing sat qr test attractiveness rating - . *** - . *** - . * - . ** ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . - . . ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . ** - . - . ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . *** - . - . ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . *** - . *** - . - . ** ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . observations r-squared . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include year-of-enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : attractiveness and gpa ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) first year gpa overall gpa attractiveness rating - . . . . * ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . * - . * - . ** - . ** ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . . - . - . ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . . ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . . - . . ( . ) ( . ) ( . ) ( . ) math sat score . ** . ** . . ( . ) ( . ) ( . ) ( . ) verbal sat score . - . . . ( . ) ( . ) ( . ) ( . ) admission rating . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . observations r-squared . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include year-of- enrollment fixed effects, race fixed effects, and financial aid amounts. table : attractiveness and gpa by area of study ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) sciences social sciences humanities area studies economics attractiveness rating . * . . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . . . - . . ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile . . . . - . ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . *** . *** . . . . . . . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . - . . . - . - . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating . *** . *** . *** . *** . *** . *** . ** . ** . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . observations r-squared . . . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all specifications include year and race fixed effects, as well as financial aid controls and controls for math sats, verbal sats, and admission rating. table : attractiveness and course-level grades ( ) ( ) ( ) ( ) ( ) ( ) attractiveness rating . . . ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . ( . ) ( . ) ( . ) attractiveness quintile = - . . . ( . ) ( . ) ( . ) top attractiveness quintile - . . . ( . ) ( . ) ( . ) math sat score . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) verbal sat score . *** . *** . . ( . ) ( . ) ( . ) ( . ) admission rating . *** . *** ( . ) ( . ) dep. var. mean . . . . . . observations , , , , , , r-squared . . . . . . standard errors clustered by student in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include fixed effects for: department, course level, semester-by-course type, year of enrollment, and race. in addition, controls include the gender of the instructor, total course enrollment (log), and the amount of financial aid received by the student. course level is either beginning, intermediate, or advanced. course type is humanities, social sciences, economics, area studies, sciences, or other. department fixed effects represent a specific department code, such as english, economics, physics, etc. table : attractiveness and course-level grades heterogeneity ( ) ( ) ( ) ( ) ( ) ( ) female prof x rating . . * ( . ) ( . ) male prof x rating - . . ( . ) ( . ) below median size x rating . . ( . ) ( . ) above median size x rating . . * ( . ) ( . ) bottom quartile x rating . . * ( . ) ( . ) nd quartile x rating . . ( . ) ( . ) rd quartile x rating . . ( . ) ( . ) top quartile x rating - . . ( . ) ( . ) ability controls y y y test of equality p-value . . . . st = nd quartile p-value . . st = rd quartile p-value . . st = th quartile p-value . . dep. var. mean . . . . . . observations , , , , , , r-squared . . . . . . standard errors clustered by student in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include fixed effects for: department, course level, semester-by-course type, year of enrollment, and race. in addition, controls include the gender of the instructor, total course enrollment (log), and the amount of financial aid received by the student. course level is either beginning, intermediate, or advanced. course type is humanities, social sciences, economics, area studies, sciences, or other. department fixed effects represent a specific department code, such as english, economics, physics, etc. table : selection into subject areas ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) sciences social science humanities area studies economics attractiveness rating - . *** . - . - . . *** ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . ** . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . * - . . - . . ** ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . ** - . . . . *** ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . *** . *** - . *** - . *** - . *** - . *** . ** . ** . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . *** - . ** . . . *** . *** . . - . *** - . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating . * . * - . - . - . - . - . - . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . observations r-squared . . . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. dependent variable is fraction of courses taken in a particular subject area. all regressions include year of enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : selection into majors ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) sciences social science humanities area studies economics attractiveness rating - . *** . - . . . *** ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . * . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . - . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . *** - . . . . * ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . *** . - . . . ** ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . *** . *** - . *** - . *** - . *** - . *** - . - . . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . ** - . ** . . . . . . - . *** - . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating . . - . - . - . - . . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . observations robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. regression specification is a probit. dependent variable is an indicator for majoring in a given subject area. all regressions include year-of-enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : attractiveness and career choice ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) consultant/manager administrator art/advertising teacher technical scientist attractiveness rating . *** . - . - . - . ** - . ** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . ** - . - . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . - . - . . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . . - . - . ** - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile . * - . - . - . - . - . * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . ** . ** - . ** - . ** - . * - . * - . - . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . - . - . - . . . . . . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating - . - . . . - . - . . . - . - . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) gpa . . - . - . . . . . . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . . . observations robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. regression specification is a probit. dependent variable is an indicator for reporting an occupation in the given area. all regressions include year of enrollment and race fixed effects, as well as controls for the amount of financial aid received. references andreoni, james and ragan petrie. . “beauty, gender and stereotypes: evidence from laboratory experiments.” journal of economic psychology, ( ): – . andrews, rodney j, jing li, and michael f. lovenheim. . “quantile treatment effects of college quality on earnings: evidence from administrative data in texas.” nber working paper . arcidiacono, peter. . “ability sorting and the returns to college major.” journal of econometrics, : – . arcidiacono, peter, v. joseph hotz, and songman kang, . “modeling college major choice using elicited measures of expectations and counterfactuals.” journal of econometrics, ( ): - . bates, timothy c. . “fluctuating asymmetry and intelligence.” intelligence, : – . beaujean, a. alexander, michael w. firmin, andrew j. knoop, jared d. michonski, theodore p. berry, and ruth e. lowrie. . “validation of the frey and detterman ( ) iq prediction equations using the reynolds intellectual assessment scales.” personality and individual differences, ( ): - . berger, mark c. . “predicted future earnings and choice of college major.” industrial and labor relations review, ( ): – . berggren n., h. jordahl, and p. poutvaara. . "the looks of a winner: beauty, gender, and electoral success." journal of public economics, ( - ): : . berri, david j., rob simmons, jennifer van gilder, and lisle o'neill. . “what does it mean to find the face of the franchise? physical attractiveness and the evaluation of athletic performance.” economics letters, ( ): – . biddle, j. and d. hamermesh. . “beauty, productivity, and discrimination: lawyers’ looks and lucre.” journal of labor economics, ( ): - . blundell richard, lorraine dearden, alissa goodman, and howard reed. . “the returns to higher education in britain: evidence from a british cohort.” economic journal, ( ): – . von bose, caroline. . “child stars vs. ugly ducklings: does adolescent attractiveness contribute to the beauty premium?” working paper. butcher, mcewan, and weerapana. . “a quasi-experimental analysis of the impact of an anti-grade inflation policy on students and instructors,” working paper. corbett, w. r. . “hotness discrimination: appearance discrimination as a mirror for reflecting on the body of employment-discrimination law.” catholic university law review, cath. u.l. rev. dale, stacy and alan b. krueger. . “estimating the return to college selectivity over the career using administrative earnings data.” nber working paper no. . daymont, thomas n. and paul j. andrisani. . “job preferences, college major, and the gender gap in earnings.” journal of human resources, ( ): – . deryugina, t. and o. shurchkov. . “are appearances deceiving? the nature and evolution of the beauty premium.” working paper. fletcher, j. . “beauty vs. brains: early labor market outcomes of high school graduates.” economic letters, ( ): - . frey, meredith c. and douglas k. detterman. . “scholastic assessment or g? the relationship between the sat and general cognitive ability.” psychological science, ( ): – . hamermesh, d. and j. biddle. . “beauty and the labor market.” american economics review, ( ): - . hamermesh, daniel s., xin meng, and junsen zhang. . “dress for success – does primping pay?” labour economics, ( ): - . hamermesh, d. . “beauty pays: why attractive people are more successful.” princeton university press, princeton, nj, usa. kanazawa, satoshi and jody l. kovar. . “why beautiful people are more intelligent.” intelligence, : – . kelly, elish, philip j. o’connell, and emer smyth. . “the economic returns to field of study and competencies among higher education graduates in ireland.” economics of education review , – . koenig, katherine a., meredith c. frey, and douglas k. detterman. . “act and general cognitive ability.” intelligence, ( ): - . landry, craig e., andreas lange, john a. list, michael k. price, and nicholas g. rupp. . “toward an understanding of the economics of charity: evidence from a field experiment.” quarterly journal of economics, ( ): - . loury, linda d. and david garman. . “college selectivity and earnings.” journal of labor economics, ( ): - . loury, linda d. . “the gender-earnings gap among college-educated workers.” industrial and labor relations review, ( ): – . mobius, markus m., and tanya s. rosenblat. . "why beauty matters." american economic review, ( ): – . mocan, naci and erdal tekin. . "ugly criminals." the review of economics and statistics, ( ): - . ravina, e. . “love & loans: the effect of beauty and personal characteristics in credit markets.” working paper. rhodes, gillian, fiona proffitt, jonathon m. grady, and alex sumich. . “facial symmetry and the perception of beauty.” psychonomic bulletin & review, ( ): - . rhodes, gillian. . “the evolutionary psychology of facial beauty.” annual review of psychology, : – . rohde, treena e. and lee a. thompson. . “predicting academic achievement with cognitive ability.” intelligence, ( ): - . scholz, john karl and kamil sicinski. . “facial attractiveness and lifetime earnings: evidence from a cohort study.” working paper. wilson, r. k., and c. c. eckel. . "judging a book by its cover: beauty and expectations in a trust game." political research quarterly, ( ): - . wiswal, matthew and basit zafar, . “determinants of college major choice: identification using an information experiment.” working paper. appendix a. rating procedure and instructions all alumna pictures were rated by at least female and male raters. raters were students at a college in a different state and were pre-screened to ensure that they were not familiar with students from the college of interest. raters were shown pictures of each student and asked to rate her physical appearance on a – point scale. five of the numbers had descriptions describing the level of attractiveness corresponding to that number (see experimental instructions on the next page). raters were instructed to choose the numbers without descriptions if they felt the student’s appearance fell between the two descriptions. each rater was shown four sets of about photos. the order of the photos within each set was randomized for each rater. in early stages of the experiment, we compared the mean and standard deviation of ratings across photo sets to see if having subjects rate pictures led to fatigue. there was no significant difference in either the mean or standard deviation of ratings for earlier and later sets, which led us to conclude that pictures was not an excessive number. we did not use data from three raters who chose ’s % or more of the time. the “ ” option was the closest to the “next” button. thus, these subjects were most likely trying to complete the experiment as quickly as possible. you are about to participate in an experiment involving the perception of appearance. once the experiment begins, you will see a photograph of an individual along with the following prompt: choose the number that best corresponds to your evaluation. choose the numbers without descriptive text ( , , , , and ) if you feel the person’s appearance falls between the descriptions found in the adjacent numbers. after you have chosen a number, click “next.” you will then see another photograph and be asked to repeat the procedure. continue selecting the number you feel best reflects your assessment of the individual’s appearance until you are told to stop. instructions for the experiment rate this person's physical appearance using the following scale: strikingly handsome or beautiful good-looking (above average for age and sex) average looks for age and sex quite plain (below average for age and sex) homely appendix b. major, course, and occupation classifications major and course classifications humanities social sciences art - history africana studies art - studio anthropology chinese environmental studies cinema and media studies history classical civilization international relations comparative literature peace & justice studies english philosophy french political science german psychology greek religion italian studies sociology japanese women’s studies latin women’s and gender studies media arts and sciences medieval/renaissance studies music russian spanish theater studies area studies science american studies astronomy chinese studies astrophysics classical & nr eastern biological chemistry east asian studies biological sciences french cultural studies chemical physics german studies chemistry jewish studies cognitive & linguistic sciences latin american studies computer science middle eastern studies geology russian area studies geosciences south asia studies mathematics neuroscience physics other economics archeology economics architecture education engineering linguistics military science physical education urban studies occupation classifications advertising/art scientist advertising/marketing researcher (except economics) political (non-government employee) earth sciences design chemistry non-technical writing biology architect astronomy performing physics publishing/broadcasting mathematics museums/galleries engineering technician consultant/manager technician manager paralegal/legal assistant consultant technical writer analysis computer-related work finance economist administrator/retail lawyer administrative/human resources lawyer retail teacher physician elementary, middle, high school physician/doctor dentist psychologist other medical nurse health worker physical therapist veterinarian does beauty matter in undergraduate education? f* tatyana deryugina, university of illinois f+ olga shurchkov, wellesley college f++ i. introduction ii. data iii. empirical framework iv. results i. admission ratings and test scores ii. grades iii. sorting v. conclusion figures and tables references appendix a. rating procedure and instructions appendix b. major, course, and occupation classifications major and course classifications occupation classifications jonathan edwards on beauty, desire, and the sensory world belden c. lane [jonathan edwards perceived the natural world as a school of de- sire. he thought that by carefully attending to the sensory splendors (and terrors) of creation, believers learn to apprehend god’s glory, which is itself more sensory than anything we can imagine. the human task of bringing the world to a consciousness of its beauty in god is full of ecological implications. as george marsden says in his new biography of edwards, “the key to edwards’ thought is that everything is related because everything is related to god.” ] the recent three-hundredth anniversary of the birth of jonathanedwards ( – ), coming as it does with a huge resurgence in edwards scholarship, offers an occasion for appreciating more fully the importance of a man who has already been considered the greatest prot- estant theologian to grace the american scene. my article is an effort to relate his writings on spirituality to contemporary discussions of beauty and ecology, asking how his thought can contribute to a christian environmen- tal ethic. while it is inaccurate to claim him as an ecotheologian, his richly sensual, almost sacramental view of the natural world is full of implications for contemporary moral practice. his work merits attention by catholics and protestants alike. in the early s, well before the first earth day celebration and even before the club of rome report on the threat of human growth to the natural environment, joseph sittler issued one of the first theological calls belden lane received his ph.d. from princeton theological seminary. he is currently the hotfelder professor in the humanities, theological studies, at saint louis university. he has recently published landscapes of the sacred: geography and narrative in american spirituality (johns hopkins university, ) and the solace of fierce landscapes: exploring desert and mountain spirituality (oxford university, ). he is now working on a book provisionally entitled nature and spirituality in the reformed tradition from john calvin to jonathan edwards. george m. marsden, jonathan edwards: a life (new haven: yale university, ) . see perry miller, gen. ed., the works of jonathan edwards, vol. , freedom of the will, ed. paul ramsey (new haven: yale university, ) introduction, . henceforth, references to the yale edition will be referred to as ye followed by the volume number and page reference. theological studies ( ) for ecological consciousness. he urged that environmental ethics should take its cue from the first question of the westminster catechism in the calvinist tradition. what is the chief end of man and woman (and of all creation, for that matter)? the answer: to glorify god and to enjoy god forever. the proper starting point for a christian attentiveness to the ecological crisis, he urged, is the exercise of delight—the enjoyment of all the mani- festations of god’s glory in the natural world around us. this is the place to begin, not with paralyzing fear over the potential of ecological catastro- phe (as real as that may be) and not with crippling guilt over the human abuse of creation (as dreadful as that is, too), but with enjoyment and delight–the true wellspring of free and spontaneous human action. draw- ing on augustine’s distinction between what we can “use” as human beings and what we should best “enjoy,” sittler argued that in matters of ecologi- cal responsibility “delight is the basis of right use.” jonathan edwards could not have agreed more. his conviction was that the natural world is a communication of god’s glory that should fill us all with desire. the conscious celebration of the beauty of god is the end toward which the whole of creation is drawn. no other theme is more prevalent in edwards’s thought. edward farley goes so far as to say that in jonathan edwards’s work “beauty is more central and more pervasive than in any other text in the history of christian theology.” humans, with their capacity to articulate wonder and to love, have a supremely prominent role in the task of giving god glory, but they do not do it alone. along with the rest of the natural world, they participate in a reciprocal process of the whole of creation being raised to the conscious- ness of its created splendor. my theme here focuses on edwards’s under- standing of the new capacity to sense the sweetness of things that believers receive as one of the graces of salvation. this sensus suavitatis had been emphasized by calvin and by the puritans before him, but edwards devel- oped it in a new way, viewing it as a perception that illuminated the truths of scripture and the magnificence of the natural world in a common ap- prehension of god’s glory. one of the difficult issues in the interpretation of edwards’s thought has been how this new “spiritual sense” should be understood. some have emphasized the idea as offering a virtual “sixth sense” by which the be- liever is equipped to perceive a spiritual reality altogether unavailable to joseph sittler, the care of the earth and other university sermons (philadel- phia: fortress, ) – . edward farley, faith and beauty: a theological aesthetic (burlington, vt.: ashgate, ) . jonathan edwards nonbelievers. others have understood it as offering a heightened and more integrated capacity to perceive reality through ordinary channels of sense experience. michael mcclymond rightly urges that both are involved, as edwards tried to argue for two deeply-held interests—the distinctively christian experience of god as a graced reality and a quality of religious experience that brings ordinary sense experience to its greatest fulfillment. edwards continually sought to integrate mind and heart in the apprehen- sion of both god’s beauty and the earth’s wonder. divine grace allows us to see the world in all its mystery, and, in turn, the world of the senses trains our perception in glimpsing god’s grandeur. this new spiritual sense, then, is a unique, god-given capacity to delight that also incorporates and en- hances natural modes of perception. the most important need we have today in confronting the ecological crisis is to recognize the intimate relationship we already share with the rest of the world around us. ethical action on behalf of the environment needs to be rooted in the awareness that we are bound together in a highly relational and deeply sensual celebration of god’s glory. we are not living human subjects that manipulate a world of lifeless objects. we are all (humans and butterflies and beech trees) created to be luminous sensory beings that mirror directly or indirectly the splendor and beauty of god. my thesis is this: for jonathan edwards, creation functions as a school of desire, training regenerate human beings in the intimate sensory appre- hension of god’s glory mirrored in the beauty of the world. humans are to respond, in turn, by articulating that glory, bringing it to full consciousness, and by replicating god’s own disposition to communicate beauty as they extend the act of beautifying to the world around them. in other words, the natural world enlarges the human capacity to sense the fullness of god’s beauty and the appreciation of that beauty subsequently leads to ethical action. nature teaches us god’s beauty which in turn drives us to its con- tinual replication in time and space. the implications of this for spirituality and the environment are many, suggesting that our purpose as a species is to cooperate with the rest of creation in its mirroring of god’s glory. hence, we dare not hinder that “great work” to which thomas berry says we all are called. jonathan edwards was never one hesitant to mention sin, and here he would state boldly: it is a sin to make ugly what god created to reflect and to share god’s beauty. michael j. mcclymond, “spiritual perception in jonathan edwards,” journal of religion (april ) . see also his encounters with god: an approach to the theology of jonathan edwards (new york: oxford university, ). thomas berry, the great work: our way into the future (new york: bell tower, ). theological studies replicating the beauty of the holy trinity the theology of jonathan edwards begins and ends with god. it focuses on an extraordinary vision of the divine beauty replicating itself in the whole of creation. contrary to the still popular stereotype of edwards as a preacher of hellfire and damnation, he was far more concerned with god as an absolute beauty to be enjoyed than with god as an absolute power to be feared. he reflected, perhaps even self-critically, after his own infamous enfield sermon on “sinners in the hands of an angry god”: “tis beyond doubt that too much weight has been laid, by many persons of late, on discoveries of god’s greatness, awful majesty, and natural perfec- tion . . . without a real view of the holy, lovely majesty of god.” the god he sought most to realize, in both his preaching and writing, was a god filled with a restless longing for relationship. what had attracted him most to the beautiful sarah pierpont in his years at yale was her familiarity with god and her extraordinary capacity for delight. he had written in the front page of his greek grammar, perhaps daydreaming in class one day: they say there is a young lady in [new haven] who is beloved of that great being, who made and rules the world, and that there are certain seasons in which the great being . . . comes to her and fills her mind with exceeding sweet delight, and that she hardly cares for anything except to meditate on him . . . . she will sometimes go about from place to place, singing sweetly and seems to be always full of joy and pleasure; and no one knows for what. she loves to be alone, walking in the fields and groves, and seems to have someone invisible always conversing with her. like sarah, edwards discovered this great being not in abstract meta- physics but in the delight he experienced in the sweet communion of na- ture. he rarely spoke of god’s essence in terms of a divine substance, after the pattern of patristic definitions of “ousia” and “substantia.” he pre- ferred to describe god more dynamically as a “disposition” to communi- cative love. it is truer, he would have said, to think of god as a commu- nicating “act” than as an existing “thing.” god is not so much a self- contained and static entity as an impulsive beauty that delights more than religious affections, ye . . “on sarah pierpont,” ye . – . in his essay on “the mind,” edwards could speak of god as the “substance” of all bodies (see ye . ) and in his essay “on being,” he referred to god as “space,” a kind of incorporeal substance existent in itself (see ye . ). yet these are exceptions that must be understood in light of his more prevalent dynamic thinking. sang hyun lee argues that edwards’s dispositional ontology is what “provides the key to the particular character of [his] modernity.” see his the philosophical theology of jonathan edwards (princeton: princeton university, ) – . jonathan edwards anything else in sharing itself. hence, a longing to extend love—a dispo- sition to communicate—forms the dynamic core of the divine being. god’s essential nature, as it were, is god’s will to act out of a longing that needs nothing whatever, but chooses longing itself as an expression of its deepest self-communication. edwards argued that god’s ravishing beauty is the first and most im- portant thing one can say of god. “god is god, and distinguished from all other beings, and exalted above ’em, chiefly by his divine beauty.” to suggest that god enjoys being god is to acknowledge that the divine splendor is a fit subject for its own endless contemplation. like sophia in the wisdom literature, god thoroughly delights in her own loveliness. understanding the theologian’s vocation as a conscientious participation in this delight, edwards anticipated balthasar in saying that “[beauty] is what we are more concerned with than anything else.” he was quick to add, however, that the divine beauty is never content with self-absorption, simply terminating in its own mirrored excellence. its nature is to shine forth, to manifest, and to communicate itself. it is a beauty that insists on being shared. within the mystery of god’s own being as holy trinity there is an eternal imaging forth of the father’s perfect beauty in his love of the son, and (in turn) their mutual delight issuing still further in the fullness of the holy spirit. god’s disposition as trinity is endlessly to delight in the shared splendor of that intimate relationship. hence the trinity’s celebration of a common joy cannot be contained for long within the divine being alone. god spontaneously seeks ever new ways of expressing love and replicating beauty, creating a world that occasions still further opportunities for self-communication and sharing. what is al- indeed, edwards can turn the older metaphysics of divine substance on its head, saying that “the delight of god is properly substance, yea an infinitely perfect substance, even the essence of god” (miscellanies, no. , ye . ). emphasis added. religious affections, ye . . edwards adds that god delights “with true and great pleasure in beholding that beauty which is an image and communication of his own beauty.” dissertation concerning the end for which god created the world, ye . . hereafter referred to as end of creation. “the mind,” no. , ye . . on the centrality of beauty in edwards’s theol- ogy, see roland delattre, beauty and sensibility in the thought of jonathan ed- wards (new haven: yale university, ). on the importance of desire in ed- wards’s thought, see paula m. cooey, “eros and intimacy in edwards,” journal of religion (october ) – . see also hans urs von balthasar, the glory of the lord: a theological aesthetics, ed. joseph fessio and john riches (san francisco: ignatius, – ) vols. edwards begins his “essay on the trinity” by speaking of the infinite happi- ness that god shares in the enjoyment of himself. see his treatise on grace and other posthumously published writings, ed. paul helm (cambridge: james clarke, ) – . theological studies ready complete in god (ad intra) nonetheless reaches out (ad extra) to extend itself in a continually greater celebration of mutual delight. god is a communicative being whose language is creation, reaching out with a love that is ever restless for more and more sensory expressions of beauty. god’s grandeur never tires of being known and relished, and, in the words of gerard manley hopkins: “it will flame out, like shining from shook foil.” for edwards, this does not imply that god needs to communicate god’s self to others in order to complete something lacking in god’s own being. god’s love, pleasure, and beauty are entirely perfect in themselves, requir- ing nothing to improve them. as a reformed theologian, edwards natu- rally affirmed the aseity of god—god’s freedom to exist without being upheld by another. the calvinist tradition insists that god would be free and glorious as god even if god had not decided to create the world. god’s self-communication, therefore, is a wholly “superfluous” action, in both etymological senses of the term. it is wholly “unnecessary,” required by nothing that is not already present in god’s own being. and it naturally “overflows” in a vast superfluity from the wellsprings of an inexhaustible source, not unlike bonaventure’s image of the world flowing from the fecundity of god’s own being. in other words, the world’s mirroring of the divine beauty does nothing to enlarge the divine nature. in one sense, god’s prior and perfect suffi- ciency remains wholly unchanged. nonetheless, as god’s effulgence is re- peated and extended in time and space, the perfection of god seems to become yet more perfect. “if the world had not been created,” edwards suggests, some of “[god’s] attributes never would have had any exer- cise.” god’s glory would have been less apparent as a result. self- contained beauty is never as lovely as a beauty in which others take delight. a perfection that elicits rejoicing is always superior to a perfection left to itself alone. hence, states edwards, “god looks on the communication of himself, and the emanation of the infinite glory and good that are in himself to belong to the fullness and completeness of himself, as though he were not in his most complete and glorious state without it.” edwards’s god is discontent with being beautiful alone. arrayed in shekkinah glory, exploding all notions of gender and difference, this god longs to be recognized by others, to be part of a mutual celebration that extends beauty and happiness in every possible direction. “god is glorified not only by his glory’s being seen, but by its being rejoiced in. when those “god stands in no need of creatures, and is not profited by them; neither can his happiness be said to be added to by the creature. but yet god has . . . a real delight in his own loveliness, and he also has a real delight in the shining forth or glorifying of it” (miscellanies, no. , ye . – ). end of creation, ye . . ibid. ye . . see also . jonathan edwards that see it delight in it, god is more glorified than if they only see it.” when this happens, edwards implies, god almost becomes “more” than god had been, as if delight in being adds something to being itself. in creating the world and sharing the divine glory with it, god’s happiness is “enlarged,” god’s pleasure made fuller. edwards also realized that this emphasis on god’s attention to god’s own beauty runs the risk of supposing that “god does everything from a selfish spirit,” as if god were some kind of vain deity—anxiously needing applause, ever hungry for approval. the northampton preacher wanted to affirm that god “enjoys himself” immensely, finding nothing more cap- tivating than god’s own beauty. but the nature of god’s joy is to remain restless until it completes itself in the delight of others. as edwards put it, shared “happiness is the end of creation,” the final purpose for which everything is made. “creation had as good not be, as not rejoice in its being.” or to express it in another way, “god, in seeking our glory and happiness, [simply] seeks himself.” creation as a communication of god’s glory this irrepressible longing ever to extend the contemplation of god’s beauty leads the divine being—in every lucid moment—to create a world that shows forth extraordinary wonder. edwards’s conception of creatio ex nihilo was a dynamic one, insisting that god’s task of continually bringing the world into being is, in every moment, an “immediate production out of nothing.” everything emerges in each instant as something new, sensu- ous, and alive, calling attention to itself and what it mirrors of the divine longing. reacting to the crass materialism of thomas hobbes, edwards wanted to understand the entire world as dependent upon god. nothing is self-reliant. god communicates god’s glory most especially in the creation of human beings, those “capable of being proper images of his excellency.” their spiritual nature is able, by grace, to respond most fully to god’s spiritual beauty. edwards is unhesitatingly anthropocentric in declaring humans the “willing active subjects [most] capable of actively promoting god’s glory.” miscellanies, no. , ye . ; and end of creation, ye . . miscellanies, no. , ye . n. . ibid. no. , ye . ; end of creation, ye . . original sin,ye . . “it [is] most agreeable to the scripture to suppose creation to be performed every moment. the scripture speaks of it as a present, remaining, continual act” (miscellanies, no. , ye . ). miscellanies, no. , ye . ; and miscellanies, no. , in the philosophy of jonathan edwards from his private notebooks, ed. harvey g. townsend (eu- gene, oreg.: university of oregon, ) . hereafter referred to as townsend. theological studies but god also communicates the divine glory through the rest of creation as well. mountains, streams, and sunlight breaking through morning clouds operate as genuine “images” or “shadows” of god’s restless desire to communicate. edwards can go so far as to say that even though this is a less direct form of communication, in some respects it may be more reliable. human beings, despite their spiritual nature, are often–on account of their sin—given to dissemblance. they can pretend to be what they are not. but the rest of nature is free from this artificiality. as edwards explains, “though beauty of face and sweet airs in man are not always the effect of the corresponding excellencies of mind, yet the beauties of nature are really emanations, or shadows, of the excellencies of the son of god.” hence, natural phenomena are able truly to mirror god’s disposition to pour herself out in reckless displays of beauty. edwards writes that: when we are delighted with flowery meadows and gentle breezes of wind, we may consider that we only see the emanations of the sweet benevolence of jesus christ; when we behold the fragrant rose and lily, we see his love and purity. so the green trees and fields, and singing of birds, are emanations of his infinite joy and benig- nity; the easiness and naturalness of trees and vines [are] shadows of his infinite beauty and loveliness; the crystal rivers and murmuring streams have the footsteps of his sweet grace and bounty. in a brief essay he wrote on the “beauty of the world,” edwards ob- served that “the fields and woods seem to rejoice,” noting “how joyful do the birds seem to be.” asking how this reflected beauty of god can so readily permeate creation at every angle, he offered an answer from his reading of newton’s optics. ’tis very probable that that wonderful suitableness of green for the grass and plants, the blue of the sky, the white of the clouds, the colors of flowers, consists in a complicated proportion that these colors make one with another, either in the magnitude of the rays, the number of vibrations that are caused in the optic nerve, or some other way. the physical structure of the universe, as he understood it, mirrors and miscellanies, no. , ye . . see john navone’s comparison of edwards and thomas aquinas in his en- joying god’s beauty (collegeville: liturgical, ) – . miscellanies, no. , ye . . edwards often used the word “emanation” in speaking of nature as a reflection of god’s glory. he did not mean this in a purely neo-platonic sense of the universe flowing out of the very essence of god. an emanation, for him, was rather a matter of spiritual significance flowing forth from sensory images that suggest a taste of something larger than themselves. see mason i. lowance, “jonathan edwards and the platonists: edwardsean epistemology and the influence of malebranche and norris,” studies in puritan american spirituality (january, ) – . “beauty of the world,” ye . . jonathan edwards bodies forth the perfect proportions of the divine beauty, striking the hu- man nervous system with a startling awakening of the senses, stirring de- light at every turn. even in a paper on the scientific study of spiders, edwards celebrated the delight that spiders take in sailing through the air on wind-borne lengths of web. he saw their behavior as exemplifying “the exuberant goodness of the creator in providing for the pleasure and recreation of all sorts of crea- tures, even the insects.” evidences of delight in nature are but a mirror of god’s own pleasure in all that god has made. for edwards, the universe is an explosion of god’s glory. but what for him was an obvious reality written across the cosmos, was not so apparent to others walking through an th-century new england meadow surrounded by red maples in the fall. edwards had to answer the question about how nature could serve as a reliable school of desire for some—leading them to god’s beauty in christ, while to others it remains opaque and indifferent. his way of explaining this difference in perception was to posit the notion of a new spiritual sense given to believers by the spirit of god at their conversion. having laid the foundation of edwards’s theology of creation in his conception of god’s communicative beauty, my concern now is to turn to the role that the natural world plays in teaching believers to “sense” the fullness of god’s grandeur. subsequently, i ask about the role that human beings play in the task of replicating god’s beauty, bringing it to still greater fullness in their own ethical responsibility, their own act of beau- tifying what has yet to be brought into the service of god’s glory. coming to a “sensory” knowledge of god for edwards, like calvin and the puritans before him, nature functions as a school of desire, teaching humans how to perceive god’s glory. the physical world, when appreciated with the new spiritual sense that regen- eration brings, gives us direct training in the multidimensional way of knowing that is necessary for meeting god. this is a knowing that involves a tasting and delighting—not just an apprehension of the mind, but an intimate engagement of all the senses as well. as an heir of john locke, edwards put a twist on the way people in the th century ordinarily spoke of knowing god in relationship to how they knew the world around them. most were accustomed to distinguishing between their knowledge of the physical world (by sensation) and their knowledge of an ethereal, non-sensory god (by faith and reason). edwards “the spider letter” [october , ], in ye . – . marsden, jonathan edwards: a life . theological studies argued, however, that god in the mystery of god’s own being is far more “sensuous”—more full of infinite delights, more prone to the endless ex- pansion of relationships, more astonishingly beautiful—than anything we can imagine in this stunningly sensuous world around us. in effect, he said, if you think this world is sensual and beautiful, you haven’t seen anything yet! all this is but a dim, quasi-sensual reflection of god’s still greater glory, overflowing spontaneously from the mystery of god’s inner-trinitarian life. that is where all desire and all connectedness find their birth. yet this sensory world, in all of its partial, secondary beauty, available to us through the exercise of our senses, trains us in the polymorphous way of knowing that is required for encountering a super-sensory god of match- less glory. as edwards put it, “the works of god are . . . a kind of voice or language of god to instruct intelligent beings in things pertaining to him- self.” one must be careful, of course, in speaking of god as a “sensuous” being. we have seen already that the core of god’s being, for edwards, is not primarily a divine “substance,” certainly not anything available to sen- sory analysis. yet the mutual delight that is shared within the exchange of the trinity is something best suggested to us by a sensory analogy. if god’s essence is a “disposition” to multiply the enjoyment of beauty, to reach out from father to son, and to spirit, and subsequently to the whole of cre- ation in a celebration of interconnected delight, then “one alone cannot be excellent.” god is ontologically hungry for relationship. hence, the inti- mate interrelatedness of all things grows out of this divine propensity (god’s own insatiable longing) for interconnectedness. edwards, therefore, does not think of god as a “sensual being.” rather god is what gives sensuality its meaning. nothing is more truly “sensuous” than the delight in harmony, beauty, and connectedness that lies at the core of the holy trinity. accordingly, if one seeks to practice the kind of knowing that is neces- sary for encountering such a god, one can look to nature as a school of desire in teaching us how to delight, how to savor and taste, how to desire the beauty to which it points. as our senses open us to harmonies of sound and delicacies of scent, as they teach us to delight in the play of light in a bubbling fountain of water, they offer a spiritual training in the knowledge of god. edwards never tired of pointing out that to “know” god is also to enjoy god. the properly-trained mind not only “speculates and beholds, but relishes and feels.” in speaking of nature as a school of desire, edwards was drawing on a images of divine things, no. , ye . . emphasis added. “the mind,” no. , ye . . religious affections, ye . . jonathan edwards long tradition of the “colloquy with the creatures.” this literary trope goes back to job’s injunction (job : ) to “ask the beasts, and they will teach you,” and to jesus’ call to consider the lilies of the field (in matthew : ). the form became stylized in augustine’s confessions when he “puts his questions to the earth,” asking the creatures, the winds, and the sky to “tell him of god.” their answer is that their beauty leads him to a beauty beyond themselves in god. the pattern was later carried on by bonaven- ture and the victorines in the middle ages and given expression again by john calvin in his commentaries on the psalms. the puritan tradition would extend it still further through richard baxter, the poetry of edward taylor, and the seventh book of paradise lost. puritan “meditations on the creatures” became an instructive device in learning how the senses of the body lead us by delight to the contemplation of god. when puritan horticulturist ralph austin imagined an extended dia- logue between a husbandman and his fruit trees, he was drawing on this time-honored motif. as he explained: “when we seriously consider the nature, and properties of inanimate creatures; then we aske questions of them; and they being thus questioned, they return an answer unto men, when we clearly perceive that their wonderfull natures, vertues, and prop- erties, cannot be, but from the power, and wisdome of a superior cause.” thomas adam, esteemed as the “shakespeare of the english puritans” because of his exquisite use of language, similarly published a series of sermons on spiritual lessons to be learned from the herbs of an english garden, clarifying their various medicinal and devotional uses. these were writers who continued bonaventure’s desire to read the vestiges of god from the wonders of creation, who echoed francis de sales’s insistence that colloquies (or “familiar talk”) with “insensible creatures” can be instruc- tive to the faithful. the calvinist usage from which edwards drew was but one strain of a much wider augustinian tradition. in describing edwards’s own conception of nature as a school of desire, one has to admit that it is not always easy to characterize his understanding of the natural world. a reading of this th-century theologian, especially as viewed by his modern interpreters, would seem to suggest that there were two very different jonathan edwardses, responding in diametrically augustine, confessions x. . ralph austin, dialogue betweene the husbandman and fruit-trees (oxford: thomas bowman, ) quoted in kitty w. scoular, natural magic: studies in the presentation of nature in english poetry from spenser to marvell (oxford: claren- don, ) n. . thomas adam, a divine herball, together with a forrest of thornes (london: george purslowe, ); bonaventure, itinerarium mentis in deum . – ; and francis de sales, an introduction to a devoute life, trans. john yakesley (rouen: cardin hamillon, ) . theological studies opposite ways to the western massachusetts landscape of which he was a part. there was edwards the empiricist and edwards the idealist. the careful observer of the natural world, avidly reading locke and newton, penning half a volume of scientific writings, finding god in the intricate beauty of the earth, this edwards seems to stand in stark contrast to the philosopher of neo-platonic sympathies who viewed all objects of percep- tion as no more than ideas of the perceiving mind, who spoke of the world as “less than nothing” from the perspective of eternity. edwards as em- piricist honored the world as a reliable and independent image of god’s glory. edwards as idealist recognized the world as upheld by the power of god alone. these two dimensions of edwards’s thought come together most clearly in his emphasis on desiring god—delighting in god’s own delight in beauty and interrelatedness. the human heart and the rest of the created world share this in common. both are shot through with a longing for intimate relationship. both participate in the attractiveness that holds all reality together. words like pleasure and delight, relish and appetite, ravishment and enjoyment continually recur in edwards’s writings, like calvin and the puritans before him. in a sermon on “youth and the pleasures of piety,” he scorned those who look down on “religion as a very dull, melancholy thing,” arguing that far from hindering the “pleasure of outward enjoy- ments,” the spiritual life actually promotes it. he referred to the highest pleasures of the soul and the highest pleasures of the sensory world in complementary ways. edwards knew that the human person is “so unsa- tiable [for god] that nothing can be found in the world [that] will satisfy him.” yet the earth serves to whet an appetite it cannot fulfill. for those with an imagination awakened by the new sense, it teaches a savoring and tasting that is the deepest way of knowing god we are capable of having. this explains why edwards, even as a child, built huts for prayer in the woods of his father’s connecticut farm. throughout his life, his ideas flowed best as he rode his horse or walked through the new england see clyde a. holbrook, jonathan edwards, the valley and nature: an inter- pretative essay (lewisburg, penn.: bucknell university, ) – , – ; sang hyun lee, “edwards on god and nature: resources for contemporary theology,” in edwards in our time: jonathan edwards and the shaping of american religion, ed. sang hyun lee and allen c. guelzo (grand rapids: eerdmans, ) – ; and paula m. cooey, jonathan edwards on nature and destiny: a systematic analysis (lewiston, n.y.: edwin mellen, ) – . see avihu zakai, “jonathan edwards and the language of nature: the re- enchantment of the world in the age of scientific reasoning,” journal of reli- gious history (february ) – . sermon on “youth and the pleasures of piety” ( ), ye . , ; and sermon on “nothing upon earth can represent the glories of heaven” ( ), ye . . jonathan edwards countryside, recording thoughts on bits of paper that he pinned to his waistcoat. on late august evenings he would lie on his back near the river, watching butterflies and moths flying toward the southeast. he loved to imagine himself “being alone in the mountains, or some solitary wilderness, far from all mankind, sweetly conversing with christ, and wrapt and swal- lowed up in god.” the physical world never ceased to operate for him as a school of desire. like earlier puritans before him, edwards carried on the classical and medieval metaphor of nature as a “second book,” another source—along with scripture—for knowing god. neither he nor the puritans saw this as a basis for establishing as such a “natural theology.” the created world does not offer us any new content, beyond what we already have in the “first book” of scripture. but, as it were, it does offer us an important exercise in epistemology. it gives us practice in a way of knowing that is far deeper and richer than the abstract speculation we usually exercise in understanding what we read. the sensory world and the sense of the heart the key to understanding the importance that edwards attributed to the sensory world is found in his emphasis on the “new sense” that believers receive as part of the revivifying work of salvation. this “sense of the heart” draws on the sensorial specificity of the natural world in training the faithful for the affective receptivity that knowing god requires. it gives life to the analogical imagination, using beauty as a way of leading the soul to god. we can identify five different aspects of this new esthetic sense that edwards employed in giving expression to a spirituality of desire. basic to his understanding the operation of the new sense is his notion of a “sensible idea.” this is the means by which we are able even to begin the task of knowing god. god can never be fully known as an object of “personal narrative,” ye . – . edwards argued, “as the system of nature and the system of revelation are both divine works, so both are in different senses a divine word, both are the voice of god to intelligent creatures, a manifestation and declaration of himself to mankind” (miscellanies, no. , townsend, ). nathanael culverwel, a th-century puritan divine and one of the cambridge platonists who influenced edwards’s thought, spoke of the limits of what we can know of god from the observations of the natural world. the book of creation offers but a shadow of the spouse’s beauty, he argued. “this way of beholding him breeds rather admiration than begets knowledge . . . and admiration is at best but semen scientia. . . . this rather sets the soul a longing, than gives it any true satis- faction.” see nathanael culverwell, spiritual opticks: or a glasse, discovering the weaknesse and imperfection of a christian’s knowledge in this life (oxford: h. hall, ) . theological studies intellection, he argued, but must be loved through a visceral and partici- patory way of knowing. edwards insisted that it is the impassioned mind, the loving mind, the mind made open to all of its senses that thinks most clearly. he was indebted here to john smith and other cambridge platonists in the th century who had contrasted the “thin, aiery knowledge that is got by meer speculation” with the “sweetness and deliciousness of divine truth” that has to be “tasted and relished” in order to be taken in. that happens when the regenerate soul is renewed by god’s spirit. “reason is turned into sense.” one receives a new capacity to embrace a “sensible idea”—to experience spiritual realities with all the vividness of a sense impression, whether visual, auditory, palatal, tactile, or olfactory. the regenerate person, for example, does not just “think” the idea of god’s radiance as an exercise of the brain in rational understanding. the wholeness of the renewed person receives the idea as a “sensation” awak- ening desire and delight. edwards described the spiritually enlightened individual’s sense of god’s excellency in this way: he does not merely rationally believe that god is glorious, but he has a sense of the gloriousness of god in his heart. there is not only a rational belief that god is holy, and that holiness is a good thing, but there is a sense of the loveliness of god’s holiness. there is not only a speculatively judging that god is gracious, but a sense how amiable god is upon that account, or a sense of the beauty of this divine attribute. one perceives the idea of god’s glory with the same sort of indisputable immediacy as one glimpses sunlight passing through falling water. in ed- wards’s understanding, the mind is a sense organ, a mechanism of knowing that “feels ideas,” that “senses concepts,” that grasps with a totality of wonder what the unregenerate mind perceives (if at all) only as an abstrac- tion. god is more “sensuous,” more compelling, more engaging and alive than any parallel one can point to in all the luscious green splendor of earth. and yet it is the physical world that opens one’s senses, that actively participates itself in the process of replicating god’s glory in time and space. edwards points to “an analogy, or consent, between the beauty of the skies, trees, fields, flowers, etc. and spiritual excellencies,” even though john smith, select discourses (london: f. flesher, ) , , . miscellanies, no. , ye . . sermon on “a divine and supernatural light” ( ), ye . . “the mind,” no. , ye . . see sang hyun lee, “jonathan edwards on nature,” in faithful imagining: essays in honor of richard r. niebuhr, ed. albert blackwell, sang hyun lee, and wayne proudfoot (atlanta: scholars, ) – . jonathan edwards he admits this connection is generally “more hid and requires a more discerning, feeling mind to perceive it.” but if one exercises that “feeling mind,” one suddenly discerns a “love and [delight] in flowers and be- spangled meadows.” one perceives “a rejoicing in the green trees and fields, [and] majesty in thunder.” through this new sense we recognize inanimate creatures—sharing in the same sensory world of god’s mak- ing—as participating in a joint apprehension of god’s beauty. the sensus suavitatis a second aspect of edwards’s conception of the “new sense” is his conviction that this way of knowing comes only as a spiritual gift, offered by god as something more than simply the exercise of the other five senses. its source is god’s grace alone. while edwards knew that god’s ravishing beauty is the most important thing to be said of god, and that the natural world witnesses to this at every hand, he was also aware that the capacity to recognize god’s glory is not immediately available to every man and woman. sin has distorted the full sensory apparatus of the human person. responding to god’s self-communication in nature, therefore, requires the exercise of a particular sense of the heart, something received in the re- generative work of the holy spirit. edwards developed this teaching out of the earlier calvinist tradition, recasting it in terms of locke’s emphasis on sensory experience and his own encounter of the great awakening. john calvin had spoken of a capacity for discerning the “sweetness “ (suavitas) of spiritual things that becomes part of the believer’s way of grasping divine truth. as calvin had put it: “man’s understanding, thus beamed by the light of the holy spirit, then at last truly begins to taste [gustare incipit] those things which belong to the kingdom of god, having formerly been quite foolish and dull in tasting them.” as early as the spring of , about the time of edwards’s own con- version, he began to speak of “a new sense of things,” an “inward, sweet delight” that came to him from his walks in the woods of his father’s farm, his reading of the canticle, and his contemplation of god. in the midst of the northampton revival in , he went on to develop the notion of the sense of the heart as what allows the believer to go beyond an intellectual comprehension of god’s glory to a sensual appreciation of its beauty. it is the difference, he would say, between rationally knowing that honey is miscellanies, no. , ye . – . emphasis added. see terrence erdt, jonathan edwards, art, and the sense of the heart (am- herst, mass.: university of massachusetts, ) – . john calvin, institutes iii. . . theological studies sweet, and being able vividly to taste its sweetness. a dozen years later, in his treatise on the religious affections, he would make this new esthetic sense one of the indicators of an authentic religious experience. what most distinguished the experience of those in the revival, he said, was not a dramatic display of religious feeling, but a new sensitivity to the world—an ability to discern beauty where it had not been apparent before. edwards said of the people in northampton after the awakening: “the light and comfort which some of them enjoy, gives a new relish to their common blessings, and causes all things about ’em to appear as it were beautiful, sweet and pleasant to them: all things abroad, the sun, moon and stars, the clouds and sky, the heavens and earth, appear as it were with a cast of divine glory and sweetness upon them.” this acquisition of an increased “spiritual appetite” was also something that edwards understood to be sustained through communion with christ in the mystery of the lord’s supper. while he mixed zwinglian and cal- vinist elements in his eucharistic theology, he nonetheless emphasized that believers become “partakers of the divine nature” in receiving christ through the sacrament. it causes “the soul to grow as food does the body,” satisfying (and increasing) the appetite god had aroused. this emphasis led to his disagreeing with his grandfather solomon stoddard over the question of open communion and ultimately to his dismissal from the northampton church in . for him, the eucharist was not just another means (like preaching) for converting the ungodly. it was a means of intimately binding believers in union with christ, feeding their new sensory appetite for holy things. a juxtaposition of sensory modes a third dimension of edwards’s conception of this new spiritual sense was its necessary mixing of sensory modes in the exuberant effort to de- scribe god’s glory. all human beings seem to have a preferred sensory channel that predominates in the way one perceives and describes reality. it reveals itself subtly in the sensory metaphors of one’s language. for edwards, like most people in the enlightenment, it was seeing (and sec- ondarily, hearing) that best conveyed the authenticity of what truly mat- “a divine and supernatural light,” ye . ; and religious affections, ye . – , – . “a faithful narrative of the surprising work of god” ( ), ye . , – , . sermon on cor. : (before ) and sermon on luke : (before ), as cited in william j. danaher, “by sensible signs represented: jonathan edwards’ sermons on the lord’s supper,” pro ecclesia (summer, ) – . jonathan edwards tered. spiritual vision was central to his perception of truth, even though he thought music was the most beautiful and perfect way of expressing glory. he once described the new spiritual sense given to the christian as a “rectified musical ear.” but generally in talking about the new spiritual sense, he chose taste as the best way to characterize it, as calvin and the puritans had also done before him. he knew that taste and flavor suggest “the immediate presence of a thing to the human palate.” in the other senses (like hearing, smell- ing, and seeing) there is a separating medium of air through which aware- ness is transferred, but not so with tasting. “taste is an intimate sense,” says diane ackerman. “we can’t taste things at a distance.” edwards’s own exercise of a sense of taste was fairly moderate, due to his poor health and simplicity of life. he often preferred a supper of bread and milk. but he and his wife sarah had a craving for chocolate that he would satisfy with packages brought back from his trips to boston. the whole family de- lighted in its taste. throughout edwards’s writings, in all the imaginative analogies he em- ployed, he drew on a wide range of the human sensorium. auditory, visual, and kinesthetic metaphors recur constantly. after his conversion, for ex- ample, god’s glory struck him most profoundly through the sound of thun- der, the bright flash of lightning, and the charged atmosphere into which he loved to run at the coming of a storm. these had been the very things that had frightened him most before his conversion. in his hand-sewn note- books, full of reflections on “images of divine things” gathered from his observations in the connecticut river valley, he wrote of song birds, flow- ing water, and the intricate movement of stars. he spoke of seeing these things, strangely enough, as the voice of god, glimpsing what is held out to us by the divine hand. this is a muddled language, as if spoken words could be perceived by the eye or images of the mind touched by one’s hand. clyde holbrook has criticized edwards’s mixing of sensory metaphors, seeing it as something that “jars the literary symmetry” of his writing. but he misses the deeper concern that underlies edwards’s use of language edwards said in his sermon on “nothing upon earth can represent the glories of heaven”: “now nothing is so pleasing naturally to the sight as light, and nothing that is the object of our senses that is so glorious” (ye . ). miscellanies, no. , ye . – . miklos veto, “spiritual knowledge according to jonathan edwards,” calvin theological journal (april ) . diane ackerman, a natural history of the senses (new york: random house, ) . images of divine things, no. , ye . . emphasis added. clyde holbrook, jonathan edwards, the valley and nature . theological studies here. sensory imagery has to be recklessly multiplied if one hopes even to begin adequately to express the glory of god. his wife sarah similarly juxtaposed images of flowing water and dancing sunlight as she reflected on her own vivid religious experience of january , . her language shares in the same ambiguity one might find in a late- th-century physicist alternating between wave and particle images of light. language, she knew, has to be twisted if it is to suggest a reality beyond normal human perception. this is how she recalled the experience: “[t]here seemed to be a constant flowing and reflowing of heavenly and divine love, from christ’s heart to mine; and i appeared to myself to float or swim, in these bright, sweet beams of the love of christ, like the motes swimming in the beams of the sun, or the streams of light which come in at the window.” edwards and his wife found the reality of god’s presence most apparent at moments of sensory overload, when one perceives in this world a brief harmony of glimpses, sounds, tastes, scents, and tactile im- pressions. this juxtaposition of sensory modes in edwards’s cognitive processing is similar to what psychologists might associate with the phenomenon of synesthesia. as an experience of “joint perception” (gk. syn-aesthesia), this is a neurological condition where stimuli to one sense mode produces sensations in one or more additional modes. certain individuals, for in- stance, can speak of “hearing colors” or “seeing sounds.” they associate numbers with particular scents or recognize musical notes as bearing dis- tinct shades of color. while this may or may not have been the case neu- rologically for edwards, his language is filled with overlapping sensory imagery of this sort. in speaking of the nature of the trinity or the mystery of god’s glory, he often juxtaposed images of sight and touch, picturing god simultaneously as light and water, “sun” and “fountain.” as if the optimal image for contemplating god were “flowing light” or “resounding touch,” a noisy, splashing waterfall through which the sun shines, making each drop of water a prism for reflecting still greater light. the works of president edwards, with a memoir by sereno e. dwight, ed. edward hickman (edinburgh: banner of truth trust, ; orig. ed. ) vol. i, lxv. emphasis added. see kevin t. dann, bright colors falsely seen: synaesthesia and the search for transcendent knowledge (new haven: yale university, ). there are similarities between edwards and bernard of clairvaux in this re- gard. bernard mcginn observes that “bernard’s employment of the spiritual senses as modes of understanding the experience of the divine presence tends to be syn- aesthetic in nature, appealing to a wide range of sense images and sometimes deliberately mingling diverse sensory perceptions” (the growth of mysticism, vol. of the presence of god: a history of western christian mysticism [new york: crossroad, ] ). see end of creation, ye . – and “essay on the trinity,” – . jonathan edwards in short, multidimensional sensory awareness was crucial to edwards’s understanding of the nature of spiritual knowing. the sensory perception of types in nature yet another aspect of edwards’s conception of the role that nature plays in the exercise of the new sense has to do with his understanding of typol- ogy. this was how he conceived the world of created things as actively “participating” in the beauty to which it points. earlier puritan practice had often drawn on “types” from the natural world to substantiate particular claims of scripture. cotton mather, for example, had written widely on meteorological matters—from thunder (in his brontologia sacra) to storms at sea. but his practice, like others, had always been to move as quickly as possible from the natural phenomenon to the truth it allegorically repre- sented. edwards, by contrast, was able to linger with the text of nature itself because of the greater attentiveness that the “new sense” made pos- sible. nature, for him, never led simply to a reality wholly beyond itself. it participated in the very mystery it represented. hence, he clearly affirmed the natural world as itself a communication of god’s majesty, one that intimately joins with humans in achieving its own goal in god’s end for creation. flowing rivers such as the connecticut and housatonic serve as more than mere stage settings for god’s drama, fo- cused exclusively on human life. they are more than empty “significations” of holy things in which they never participate—allegorical hints of the rivers of paradise, for example. for edwards, their splashing movement, the way their waters reflect light, the play of sun and shadows along their banks offer a direct apprehension of god’s glory and majesty. they com- municate this by themselves as representative “images and shadows” that require the participation of human perception in bringing them to the completion of their divine purpose. similarly, the attraction of gravity, the delight of bees in the sweet taste of pollen, the relish and appetite of babies for breast milk, the intimate union of a branch grafted onto a fruit tree, the sexual appeal of a wife to her husband—all these serve, he proclaimed, as teachers of desire drawing us to god. see mason i. lowance, jr., “ ‘images or shadows of divine things’ in the thought of jonathan edwards,” in typology and early american literature, ed. sacvan bercovitch (amherst: university of massachusetts, ) – ; and janice knight, “learning the language of god: jonathan edwards and the typol- ogy of nature,” william and mary quarterly third series : (october ) – . see conrad cherry, nature and the religious imagination: from edwards to bushnell (philadelphia: fortress, ) . images of divine things, ye . , , , , . perry miller said that theological studies the nature imagery that edwards found most persuasive—most able to trigger an experience of god’s glory (with all the spiritual sensuality that involves)—were images that powerfully suggest a sense of reciprocal in- teraction. he exulted in images of effulgence and refulgence, the gleaming forth of light and its being reflected back again, as in play of moonlight on the surface of a river. dynamic images that highlight the relationships between bodies were the ones that intrigued him most. as he expressed it with poetic splendor: “in the creature’s knowing, esteeming, loving, rejoic- ing in, and praising god, the glory of god is both exhibited and acknowl- edged; his fullness is received and returned. here is both an emanation and remanation. the refulgence shines upon and into the creature, and is re- flected back to the luminary.” this keen observer of the landscapes of desire in th-century new england knew that human language itself is deeply rooted in the sensory world. the only communication skills available to us are derived from our human experience of embodiment. this alone is what serves us in speaking of god. nothing is more suited for analogically suggesting the “super- sensory” reality of god, edwards thought, than the concrete specificity of human language and the physical world out of which it arises. in describing the genesis of language, he explained that: “the names of spiritual things, or most of them, [are] derived from the names of sensible or corporeal ones . . . because there was no other way of making others readily under- stand men’s meaning when they first signified these things by sounds, than by giving of them the names of things sensible to which they had an anal- ogy.” he would have recognized generative words like “companion” and “supercilious,” for example, as having their source in the bodily experience of eating bread with another or raising one’s eyebrows in haughty arro- gance. anticipating emerson’s intimate dependence of human language on the physical world, edwards knew that the human being—like god—is necessarily a communicative being whose language is creation, ambiguous and accommodated as that always is. the new sense and the beauty of the cross a fifth and final aspect of edwards’s understanding of the sense of the heart as it relates to the natural world has to do with the role that nature edwards, in this work, offered “nothing less than an assertion of the absolute validity of the sensuous” (images or shadows of divine things by jonathan ed- wards, ed. perry miller [new haven: yale university, ] ). end of creation, ye . . “the mind,” no. , ye . . jonathan edwards plays even in teaching us the way of the cross. the whole creation, in its groaning and travail as it awaits the promised glory, models the frustration of holy desire that human sinfulness has brought into the world. the earth suffers continually at the hands of human abuse. edwards seems almost to speak with an ecological sensitivity in deploring the “abusive improvement that man, who has the dominion over the creatures, puts the creatures to.” he scorns this misuse as “a force upon the creature; for the creature is abused in it, perverted to far meaner purposes than those for which the author of its nature made it.” he grieves over humans killing brute crea- tures by the “thousands and millions” every day, making the earth a “meat shop of sin.” however, one must resist stylizing jonathan edwards as a proto- envirotheologian. while his thinking may be full of ecological implications when read from a contemporary perspective, he had no intention of pro- viding an environmental ethic aimed at protecting the natural world. his concern was more with the tragedy of human sin than the destruction of the environment. in an unpublished sermon on romans : , edwards lamented the extent to which the created world is “debased below its nature” by human pollution. “no wonder the whole creation is represented as groning [sic] under such an abuse & in being held under such bondage,” he exclaimed. he not only decried the number of animals that humans daily destroy “to satiate their vicious appetites,” but warned that if domin- ion-sated human beings (the “cumberers of the ground”) continue in their sin “the creation will surely spew you out . . . . the world will disburden it self of you & and you shall be cast forth as an abominable branch.” he knew that god’s most astonishing beauty lies hidden in the earth’s suffering, because the anguish of nature points also to the agony of the cross. for edwards, the highest expression of god’s glory revealed in creation is witnessed in the god-become-creature who died on golgotha. in the humiliation of christ we find the greatest consent of the creation to its maker. the creator becomes in this moment the lowest of all creatures on earth. the power of consent, the unity of being, the persuasiveness of the senses, the centrality of embodiment to the apprehension of god’s glory—all these are discovered here at the cross. “an humble attempt,” ye . . in a sermon titled “east of eden,” edwards said of the earth that god had put his own beauty upon it; it shone with the communication of his glory.” but as a result of human sin, “the earth lost its beauty and pleasantness . . . that bloom and beauty and joy that all nature seemed to [be] clothed with was gone” (ye . ). unpublished manuscript sermon on romans : , “the whole creation does as it were groan under the sins of wicked man” ( ), beinecke rare book and manuscript library, yale university, . ibid. , , . theological studies edwards echoed calvin and augustine before him (anticipating balthasar after him) in affirming that god is beautiful, not only in the loveliness of the earth, but even “beautiful on the cross.” obviously it is a long stretch, by any reach of the imagination, to discern beauty in the midst of pain. but once again it is the “new sense” imparted by god’s spirit that makes this discernment possible. the new capacity for perceiving god’s beauty makes one simultaneously more sensitive to deformity, more attentive to the distorting of god’s mirrored loveliness. it breeds a resis- tance to the disfiguring of the world’s beauty as well as an identification with that which is most disfigured. beauty requires this, for it is the nature of god’s beauty never to be static. god continually reaches out to beautify, to embrace in love, to reclaim what is lost. in the strange beauty of the cross, we perceive the extent to which god goes in assuming the full brokenness of creation. here we grasp most dramatically god’s disposition to communicate with reck- less longing. edwards found christ’s highest beauty in “the greatest degree of his humiliation.” “never [more than at the cross] was his divine glory and majesty covered with so thick and dark a veil . . . yet never was his divine glory so manifested by any act of his, as in that act of yielding himself up to these sufferings.” here, in the agony of the cross, the exquisite beauty of the holy trinity is finally discerned most perfectly—at least to eyes made able to see. through the gift of the sensus suavitatis one is able to know, even in the midst of apparent despair, that the world in the end is saved by beauty. long before dostoyevsky and berdyaev, edwards recognized this truth. but he went on to argue that understanding beauty in this way requires the acceptance of an ethical imperative that comes along with it. the beauty of the cross demands not only an intellectual comprehension of radical abandonment, but a practice of it in one’s own christian experi- ence. this is what imitators of a triune god have to risk for the sake of love. “true happiness, the crown of glory, is to be come at in no other way than by bearing christ’s cross, by a life of mortification, self-denial and labor.” the new sense is brought to full exercise only as it expresses itself finally in a life of concrete, sensory identification with those who suffer. the surest test of an authentic work of the spirit, edwards urged, is an eager- see carol harrison, beauty and revelation in the thought of saint augustine (oxford: oxford university, ) – . hans urs von balthasar similarly points “through the ghastliness of the crucified, the seeming absence of all beauty [to] the breakthrough of the flaming mystery of the glory of love: fulget crucis mysterium” (“earthly beauty and divine glory,” communio [fall ] ). sermon on “the excellency of christ” ( ), ye . . images of divine things, no. , ye : . jonathan edwards ness to reclaim the hidden beauty of those who remain unloved. necessar- ily, he said, “grace tends to holy practice.” delighting in beauty and bestowing it my concluding concern here is to identify more specifically the human responsibilities that derive from this distinctive esthetic awareness made possible by the new sense. if, as edwards argues, god’s deepest inclination or disposition is to communicate beauty for the sake of love, and if we as humans are prime recipients of that beauty in the mystery of the cross, then how do we extend the act of beautifying to the rest of the creation around us? how do we continue to replicate god’s glory in time and space? what particular shape should it take in human speech and action? for jonathan edwards, esthetic sensitivity must always reach out to something beyond itself. glory is instinctively communicative. frank burch brown says that for all augustinians, “the greater the art’s beauty, the greater the sense of yearning that it evokes.” it inevitably makes one hungry for more than it is able to satisfy. beauty never ends in itself, therefore. there is no “art for art’s sake.” esthetics and ethics are neces- sarily joined. hence, even as god’s own beauty is inherently disposed to the beautifying of others, so the new sense in edwards must lead to the adorning work of love exercised as justice. near the end of his life, as a missionary to the housatonic indians in western massachusetts, edwards wrote a pair of exquisite dissertations on the nature of beauty and its impact on the human soul. his dissertation concerning the end for which god created the world focused on the magnificence of god’s reflected beauty in creation and his dissertation on the nature of true virtue attended to the ethical implications of the con- templation of this beauty. in the latter he defined true virtue as a process of being so transfixed by the beauty of god as being-in-general that those who perceive such glory are able also to grasp the as-yet unrealized beauty of every being-in- particular. true virtue is a disposition (or habit of heart) that recognizes and extends the beauty of god into continually new expressions of love- liness. to exercise this virtue is to participate in god’s own disposition to communicate glory, bringing what is still an indiscernible beauty into con- tenth sermon in charity and its fruits, ye . . see also gerald r. mcder- mott, one holy and happy society: the public theology of jonathan edwards (university park, penn.: pennsylvania state university, ) – . frank burch brown, good taste, bad taste, & christian taste: aesthetics in religious life (new york: oxford university, ) . the nature of true virtue, ye . ibid. ye . . theological studies sent and union with god’s own matchless grandeur. what we love in the particular person or thing is the contingent fullness of god’s own beauty, wanting to replicate itself still further in creation. god, after all, is “the foundation and fountain of all being and all beauty.” admittedly, love of “being-in-general” may at first seem extremely amorphous, lacking any passion—a matter of loving everything in general and nothing in particular. but to put god’s magnificence at the center of attention is to allow oneself to love not only what is already there in the person or thing, but also the mysterious potential of the other as one grasps more fully its relation to god. we perceive what is “greening” itself within, growing into a beauty that is yet incomplete, to use the language of hilde- gard of bingen. to act ethically, then, is to act as if there truly are interrelated harmonies that exist among all beings as they cohere together in god. this is not only to perceive (and celebrate) the mirror of god’s beauty in every single being, but to engage in “joyful, beautifying activity” of our own. roland delattre observes that, for edwards, “beauty . . . is more fully exhibited in bestowing beauty than in receiving it.” two implications derive from this ethical impulse in his thinking. the first is that extraordinary attentiveness and moral passion are demanded of all the lovers of god, as they help to bring the world to a consciousness of god’s glorious presence within it. the meticulous powers of observation and literary artistry of an annie dillard and mary oliver are invaluable aids to the theologian’s craft, drawing lines of interconnectedness across the cosmos, inciting a wonder that necessitates action. the second is that the work of recognizing and bestowing beauty has to be sustained ulti- mately by a transcendent and eschatological hope. it draws its strength from gregory of nyssa’s contention that our longing for god’s beauty is never finally satisfied, but presses on from glory to glory—stretching itself into eternity in its ever-expanding sensual capacity to appreciate (and ex- tend) beauty everywhere. ibid. ye . . edwards explains that, “all the beauty to be found throughout the whole creation is but the reflection of the diffused beams of that being who hath an infinite fullness of brightness and glory” ( . ). roland a. delattre, “religious ethics today: jonathan edwards, h. richard niebuhr, and beyond,” in edwards in our time: jonathan edwards and the shap- ing of american religion, ed. sang hyun lee and allen c. guelzo (grand rapids: eerdmans, ) – . emphasis added. paul ramsey compares edwards’s doctrine of perpetual progress in heaven and its relation to gregory of nyssa in ye : – . see also patricia wilson- kastner, “god’s infinity and his relationship to creation in the theologies of gregory of nyssa and jonathan edwards,” foundations : (october–december, ) – . jonathan edwards bringing the world to a consciousness of its beauty in god to contemplate the divine glory aright, according to edwards, is to make the universe conscious of its own being. humans function as “the con- sciousness of the creation,” he argued. theirs is the responsibility of discerning and articulating the esthetic/moral character of the cosmos as a mirror of god’s glory. theirs is the task of pursuing the scientific (and liturgical) work of identifying interrelationships within the universe at large. they show how god’s beauty fills the earth in the exercise of the principles of attraction, cohesion, consent, and proportionality that char- acterize the dynamic life of the created world. without this cognizance of its interconnectedness in god, the cosmos remains at risk. we mend its fragility by restoring the awareness of its coherence in god. “except the world had such a consciousness of itself, it would be altogether in vain that it was,” edwards could say. our task as a species, therefore, is to identify and honor the conjoining of all interlocking systems in the speechless splendor of creation, bringing everything to its fullness in the glory of god. to use the language of thomas berry and brian swimme, we are the earth’s activity in being aware of its future. we are “the self-reflexion of the universe,” allowing it “to know and feel itself.” the role of human beings is to contemplate god’s beauty in the second- ary beauty around and within them, to bring to conscious celebration what remains only implicit. as george herbert put it, following in the puritan tradition of meditations on the creatures, humans serve the rest of the world as a “secretary of god’s praise.” this is no passive and individu- alistic activity, no absorption in the private contemplation of self-contained beauty. it demands the most careful and responsible study of the whole of creation, searching its particularities and relationships for every single “vestige” of the hand of the creator, as bonaventure would say. jonathan edwards was fascinated by th-century science and philoso- phy, delighting in its attention to the intricacies of the natural world, its grand celebration of symmetry and order. but he directed its conclusions toward far different ends than deistic thinkers like john toland and mat- thew tindal had done. they perceived the self-contained harmony of the universe as ruling out the personal involvement of the divine. such inter- edwards, miscellanies, no. , ye . . ibid. thomas berry, the dream of the earth (san francisco: sierra club, ) – ; and brian swimme, the universe is a green dragon (santa fe: bear & co., ) . george herbert, “providence,” in john n. wall, ed., george herbert: country parson, the temple (new york: paulist, ) . theological studies vention, as they perceived it, was derogatory to god’s omnipotence and unchangeableness. edwards, by contrast, saw the new science as revealing a god of intimate relationships hidden within the very structure of the universe. symmetry and interlocking order are indicators of a warm, con- vivial affinity, not cold indifference. his quest, then, was to incorporate enlightenment science into the service of mystical union with christ. the way one thing relates to another was continually what most occu- pied edwards’s mind, as a scientist and theologian alike. “reality is a matter of relationship for [him],” said wilson kimnach. “the higher the truth the greater the extent of relationships involved.” the massachusetts pastor was overwhelmed by the interconnecting unities that make up the universe. “when we think of the sweet harmony of the parts of the cor- poreal world,” he exclaimed, “it fills us with such astonishment that the soul is ready to break.” as one might express it today, the awareness of god’s beauty filling the earth inevitably drives us to ecological thinking, to the recognition of the mysteries of gaia, to the maintenance of those bonds of interrelationship and recyclings of energy that join all living beings in a great whole. “it was, perhaps, the profoundest insight of the eighteenth century that a thing becomes meaningful when we discern its relation to something else,” says another recent interpreter of edwards’s thought. he was ever attentive to the “general agreeing and consenting together” of interrelated bodies in the operation of the universe. he remained spellbound by the “agreeablenesses” that one discerns “between the colors of the woods and flowers and the smell, and the singing of birds.” at times, he could sound like contemporary exponents of chaos theory who speak of the butterfly effect, noting how the beating of a butterfly’s wings in china can alter weather patterns in new york city. the complexity and unpredictable wonder of the world was, for him, an expression of god’s holding all things in dynamic, ever-changing relationship to each other (and to god’s self). gravity, for example, was but an expression in the realm of physics of the “attraction, or the mutual tendencies of all bodies to each other.” to respond to god’s beauty, then, is to value and nurture these various inter- relationships, beginning to think like a mountain as aldo leopold said, being sensitive to all the ways that ecosystems and biotic processes operate together to sustain mutuality and homeostasis in the maintenance of life. wilson kimnach, “jonathan edwards’s pursuit of reality,” in jonathan ed- wards and the american experience, ed. nathan o. hatch and harry s. stout (new york oxford university, ) . miscellanies, no. , ye . . leon chai, jonathan edwards and the limits of enlightenment philosophy (new york: oxford university, ) . “the mind,” no. , ye . ; and “the beauty of the world,” ye . . jonathan edwards this, edwards thought, is an expression of the finest exercise of god’s glory. accordingly, “it is requisite that the beauty and excellency of the world, as god has constituted it, should not be kept secret.” ecological ethics and eschatological hope if ethical practice is necessary to preserve the world in its divinely appointed task of evincing god’s beauty in the joining of all things together in love, it is also necessary that this practice be anchored in an eschato- logical hope. only there can it find the power able to sustain deliberate action. the task of continually recognizing and extending beauty is one that reaches ultimately into eternity. indeed, the earth itself participates in a longing that yearns for the fullness of interelatedness that redemption (in and beyond history) finally brings. edwards says, “though the creature is [now] subjected to vanity, yet it don’t rest in this subject, but is constantly acting and exerting itself in order that the glorious liberty that god has appointed [might appear]. . . . all the creatures, in all their operations and motions, continually tend to this.” edwards’s theology is unequivocally god centered and future oriented, reminding one at times of teilhard de chardin. he is a god-intoxicated thinker, seeing everything to cohere at last in the holy trinity. it might seem strange to root an environmental ethic in a theology of profound transcendence. but edwards would say that there is no foundation for the true worth of the world in anything less than god. in a boldly theocentric theology anthropocentrism is radically judged. for edwards, human beings realize their createdness most fully, not in their exercise of dominion, but in their ability to delight, to extol beauty and nurture relationship. more- over, this practice of delight is one that reaches with the rest of creation to a realization beyond the immediate limits of history. edwards’s keen ex- pectation of the coming millennium included a confidence that natural phenomena will be seen and known still more perfectly in the age to come. he concludes that: “[t]he late invention of telescopes, whereby heavenly objects are brought so much nearer and made so much plainer to sight . . . is a type and forerunner of the great increase in the knowledge of heavenly things that shall be in the approaching glorious times.” paula cooey argues that “understanding edwards’ apocalypticism is es- sential to understanding his view of nature.” admittedly, at times he seems ambivalent about the continuity of the present world of nature in the age images of divine things, no. , ye . . “an humble attempt,” ye . . images of divine things, no. , ye . . theological studies to come, twisted as it is by sin. he can speak of the “very material frame of the old heavens and old earth” as finally being “destroyed” so that a new heaven and earth can be created. after all, once one has seen (in the beatific vision) the ultimate beauty to which the physical world as a school of desire has pointed all along, there is no need any more for a teacher. on the other hand, edwards knew that one never stops learning, and longing, in the unending sensory process of knowing/delighting in god’s beauty. thus, he declared that the heaven to which the saints are taken in the “new heavens and new earth” will still be a part of this universe, where the laws of nature continue to apply. it will be a “place of the habitation of bodies as well as souls, a place wherein their bodily sense shall be exer- cised.” human sensory perception and the exercise of delight will not only persist there, but be extended in remarkably astounding ways. “the beauty of the bodies of the saints in the new earth . . . shall not only consist in the most charming proportion of features and parts of their bodies, and their light and proportion of colors, but much in the manifestation of the excellencies of their mind . . .” all manner of sensory enhancements will accompany the embodiment of the saints in heaven. edwards anticipated their range of hearing and seeing to be vastly improved, enabling them to perceive multiple ratios of reso- nance that make up a single harmony or to glimpse “the beauty of anoth- er’s countenance” at a thousand miles distance. how ravishing are the proportions of the reflections of rays of light, and the proportions of the vibrations of the air! and without doubt, god can contrive matter so that there shall be other sort of proportions, that may be quite of a different kind, and may raise another sort of pleasure in a sense, and in a manner to us inconceivable, that shall be vastly more ravishing and exquisite. . . . there shall be external beauties and harmonies altogether of another kind from what we per- ceive here, and probably those beauties will appear chiefly on the bodies of the man christ jesus and of the saints. for jonathan edwards, the spiritual life is eternally a sensuous life. it carries with it the hope of a continual expansion of sensory delight in the splendor of god. such is what finally gives this world and the next their enduring worth and importance. the ecological responsibility that humans share for the biosphere in which they live is intricately tied to the earth’s role in reaching with them toward the endless expansion of god’s beauty. cooey, jonathan edwards on nature and destiny . history of redemption, ye . . miscellanies, no. , ye . – ; and “apocalypse series,” no. , in ye . . miscellanies, no. , ye . . ibid. no. , ye . – . jonathan edwards conclusion in conclusion, we find in jonathan edwards a theologian who under- stands the contemplation of the natural world as an exercise in prayer. the physical universe is, for him, a mirror of god’s glory, participating in what it reflects. the world is not simply a thin veil through which we reach toward a god wholly beyond it. for edwards, nature—in all of its sensory palpability—is itself taken up into the still more sensuous glory of god. in the process, it teaches us desire, opening its mysteries to all those who have received a new sense for the perceiving and extending of beauty in their common life. it would be inappropriate to project back onto jonathan edwards in his th-century setting a developed ecological sensitivity. yet the richly sen- sual spirituality that he taught is highly compatible with contemporary environmental concerns. as he himself affirmed, we share necessarily in the sufferings of the earth, straining at times to recognize the hidden and marred beauty within it. as we apply his theology years later, we ourselves need to assume responsibility for the abuses we have brought upon the planet. in polluted rivers and smog-filled skies, we confront again the agony of the cross. god’s own deepest longing to communicate beauty, witnessed most poignantly at golgotha, demands of us the mending and nurturing of interrelationships among all that lives. if it is true that, as humans, we share with all other creatures a common capacity to delight in the sweet taste of life itself, if we are in some way “family”—joined by social ties that have their roots in the trinitarian life of god—and if the future toward which we are growing involves a sabbath rest embracing the whole of creation, then we simply cannot act any longer as if we were disconnected from a lifeless universe toward which we bear no responsibility. we need to commit ourselves, at last, to honoring the web of life, with all of its intimate connections. the very beauty of god requires this of us. theological studies revista arquivos ( )) - ingles.pmd int. arch. otorhinolaryngol., são paulo - brazil, v. , n. , p. - , jan/feb/march - . original article int. arch. otorhinolaryngol. ; ( ): - . doi: . /s - rhinoplasty and its effects on the perception of beauty hernan chinski , luis chinski , jenny armijos , juan pablo arias . ) medical doctor (staff physician, rhinology and facial plastic surgery, ent department, university of buenos aires, argentina) ) medical doctor (staff physician, ent, head and neck surgery, university of buenos aires, argentina) ) medical doctor (resident, ent department, university of buenos aires, argentina) please send correspondence to: hernan chinski ent department, hospital de clinicas, university of buenos aires, buenos aires, argentina charcas ro a article received on august , . article accepted on october , . summary introduction: experts on nasal cosmetics and nasal surgery agree that aesthetic rhinoplasty leads to overall facial beautification and the perception of youth in patients. this “assumed truth” has never been proven in the international literature. aim: to examine increases in facial attractiveness ratings after rhinoplasty surgery. methods: we conducted a study series by choosing female patients on whom we had operated and evaluators in a single blind trial. the evaluators graded the patients’ attractiveness before and after surgery. results: beauty indices were significantly improved after the operation. conclusion: according to the third-party evaluation, the patients appeared prettier after undergoing aesthetic rhinoplasty. keywords: rhinoplasty, beauty, perception. were obtained by the same person with the same camera in identical light conditions, the same setting, and from the same perspective and distance. the photographs were loaded onto microsoft powerpoint slides ( displayed per patient, one preoperative and one postsurgical). each slide displayed photographic angles (front, profile, and ¾) (figure ). introduction rhinoplasty is an existing surgical practice intended to return nasal harmony to a patient. surgeons assume that patients will look prettier and younger after the operation. this statement may appear obvious, but the international literature contains no statistical study that proves this. the aim of our work was to prove that impartial evaluators’ perception of the beauty and youth of patients aged – years would increase after the patients had undergone primary rhinoplasty. our results are statistically significant. method the present study included patients who had undergone primary rhinoplasty at hospital de clinicas and the cechin otolaryngology centre in buenos aires, argen- tina, between and . we used facial photographs of the patients, including front, profile, and ¾ angles. the recruited patients had typical defects such as nose tip drop and nasal dorsum hump. all cases involved open rhinoplasties using redistributive and non-resective techniques ( ). photographs were obtained before and after (at least months) each patient’s operation. all photographs figure . example of patient used in the study. top photograph is pre-operative. bottom photograph is post-operative. note that the subject is pictured from the front, ¾, and profile angles. t h is d o cu m e n t w a s d o w n lo a d e d f o r p e rs o n a l u se o n ly . u n a u th o ri ze d d is tr ib u tio n is s tr ic tly p ro h ib ite d . figure . distribution of patients in groups of slides each. each slide in the group exhibits pre-operative and post-operative patient pictures captured from the front, ¾, and profile angles. figure . a table (left) displaying the random patient distribution in groups in pre-operative or post-operative order. a scan of the survey conducted by an evaluator (right). groups of slides were assembled, with each pair of photographs randomly distributed into pre-operative (a) and post-operative (b) groups (see figure ), thus ensuring no photograph was exhibited twice in the same group. the slides were displayed using microsoft excel’s randomization system (figure , left). we recruited medical students to perform the evaluations, but did not divulge the reason for the evaluation. they were asked to participate voluntarily, and received no monetary compensation. the students were shown consecutive pictures from groups a and b (figure ). after viewing each slide for seconds, the students scored each photograph for ( ) facial attractiveness according to a visual analogue scale ( – ; = very ugly, = very beautiful). age also was ranked, with the evaluators asked to note the suspected age of the person in each photograph. students were told that they would view repeat pictures but that the repetition would be random. viewing more than slides, we assumed it would be highly unlikely that the evaluators would remember the scores they had given to specific subjects previously. the students were not informed that the nose of the patients in the photographs had been altered surgically, nor was any other information provided. the data were recorded on tables designed especially for this study (see fig. , right). int. arch. otorhinolaryngol., são paulo - brazil, v. , n. , p. - , jan/feb/march - . rhinoplasty and its effects on the perception of beauty. chinski et al. t h is d o cu m e n t w a s d o w n lo a d e d f o r p e rs o n a l u se o n ly . u n a u th o ri ze d d is tr ib u tio n is s tr ic tly p ro h ib ite d . the aim of this study was to evaluate data and verify significant differences between scores before and after the surgery. in the present study, we posed the following hypotheses: ( ) rhinoplasty has positive effects on beauty; the post-rhinoplasty beauty index is higher than the pre- rhinoplasty index, and ( ) rhinoplasty significantly decreases perceived age. results all included parameters were inserted into an excel table: one table per presentation. following the introduction of each set of patient and variable data, we compiled a database with spss (statistical package for the social sciences, version . ). tables and list the averaged results, including pre-operative and post-operative standard deviation and error. the average pre-operative beauty ranking on a visual analog scale of – was . , whereas the post- operative beauty ranking was . . the average age guessed for individuals in pre-rhinoplasty photographs was – years, whereas the average post-rhinoplasty age guessed was – years. p = . was established for improved facial beauty and p = . for the appreciation of age. discussion facial beauty perception has been studied broadly over the past decades ( ). studies on facial proportionality indicate its influence on the perception of beauty ( ). certain studies have evaluated beauty after treatments such as nasal reconstruction ( ) and orthodontics ( ). fan et al. studied physical attractiveness in women based on the body mass index; slim women were deemed more attractive ( ). most studies have used a visual analog scale from – ( = not pretty; = very pretty) ( – ). several studies also have evaluated patient satisfaction and self-perception of beauty, but these types of efforts do not match the assessment of an external observer. prior studies have not evaluated primary rhinoplasty outcomes in terms of beauty, nor has perceived age been evaluated. after undergoing rhinoplasty, most patients appear much younger. table . survey results (average). pre-operative post-operative patient age beauty age beauty , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , table . survey results (averages, and standard deviation and error). variabel group averange standar deviation standard error beauty pre , , , post , , , age pre , , , post , , , figure . photograph of evaluation period; note slide projection and evaluator note taking. int. arch. otorhinolaryngol., são paulo - brazil, v. , n. , p. - , jan/feb/march - . rhinoplasty and its effects on the perception of beauty. chinski et al. t h is d o cu m e n t w a s d o w n lo a d e d f o r p e rs o n a l u se o n ly . u n a u th o ri ze d d is tr ib u tio n is s tr ic tly p ro h ib ite d . our team studied the effects imparted by rhinoplasty on the perception of facial beauty (i.e., that patients’ faces would appear more attractive after the operation). we wish to highlight that the surgery is performed only on the nose; however, the face as a whole ultimately looks more attractive. certain studies have shown that a person focuses on the eyes, mouth, and ears when meeting someone for the first time; in the presence of an aesthetic facial defect, the individual focuses on the defect or asymmetry. we understand that a natural outcome of rhinoplasty is that a patient is viewed as being prettier overall based on holistic perception of the face, and not only from having a prettier nose. regarding age, we were amazed to discover a lack of significant differences regarding perceived patient age pre-rhinoplasty and post-rhinoplasty. we believe inherent rejuvenation occurs due to rhinoplasty, but this was not reflected in this study. for future studies, we believe that variables should be corrected to prove the influence of rhinoplasty on the perception of age: ( ) use an older group of patients for whom rhinoplasty would create a greater difference in the perception of age, ( ) photograph post-operative patients within – years after surgery, and ) enroll patients with nasal tip drop because the rejuvenation effect is far greater than in cases corrected by descendant rotation. we will make these adjustments in future studies. conclusion this study proved that patients who have undergone rhinoplasty appear more beautiful. we conclude that rhinoplasty influences facial beauty positively and in a statistically significant manner. with regard to age, we observed a rejuvenation effect. references . chinski h, chinski l. “rinoplastía redistributiva vs. rinoplastía resectiva. cambio de paradigma en la cirugía de rinoplastía” revista de la federación argentina de sociedades de otorrinolaringología. año . n . año . . marck s. nestor, subjetive and objective facial attractiveness ratings and gender differences in objective appraisals of female faces. the journal of clinical and aesthetic. ; : - . . raymond e, pragaty a. the use of anthopometric proportion indices in the measurement of facial attractiveness. european journal of orthodontics. : ; - . . sanne e. moolenburgh. aesthetic outcome after nasal reconstruction: patient versus panel perception. journal of plastic, reconstrucive aesthetic surgery. ; : - . . mirjam h, gernot g. the ideal of facial beauty: a review. journal of orofacial orthopedics. ; : - . . j. fan, f. liu, j. wu and w. day. visual perception of female physical attractiveness. the royal society. ; : - . . r.m.a kiekens. influence of panel composition on aesthetic evaluation of adolecent faces. ; : - . . yosh jefferson. facial beauty establishing a universal standard. ; : - . . zlatko devcic, koohyar k. a web based method for rating facial attractiveness. the laryngoscope. ; : - . int. arch. otorhinolaryngol., são paulo - brazil, v. , n. , p. - , jan/feb/march - . rhinoplasty and its effects on the perception of beauty. chinski et al. t h is d o cu m e n t w a s d o w n lo a d e d f o r p e rs o n a l u se o n ly . u n a u th o ri ze d d is tr ib u tio n is s tr ic tly p ro h ib ite d . small, beautiful and magnetically exotic: {v w }- and {v w }-type polyoxometalates dalton transactions communication cite this: dalton trans., , , received th june , accepted th june doi: . /c dt k www.rsc.org/dalton small, beautiful and magnetically exotic: {v w }- and {v w }-type polyoxometalates† maren rasmussen,a christian näther,a jan van leusen,b ulrike warzok,c christoph a. schalley,c paul kögerler*b and wolfgang bensch*a minimal-nuclearity vanadato-tungstate clusters in [{viv(dien)} - wvi o ]· h o ( ) and [{v iv(dien)} w vi o ]· h o ( ) feature cores of edge-sharing wo octahedra, surrounded by a ring of four vanadyl groups. surprisingly, the v(iv) centers in both and are ferro- magnetically coupled, in contrast to all other known vanadato- polyoxotungstates featuring the ubiquituos v–o–w–o–v exchange pathways. the chemistry of mixed-metal polyoxometalates has witnessed an impressive development during the last few decades, with synthetic and structural aspects, properties and possible appli- cations summarized in several review articles. the first mixed v–w polyanions were reported already in the th century; efficient synthesis protocols were developed for the lindqvist- type polyanions [vxw −xo ] − −x (x = , ), the solution stabi- lity of which is strongly ph dependent. the chemistry of mixed tungstato-vanadate compounds was further developed, resulting primarily in several compounds containing {vxw −x} (x = – ) lindqvist anions, where v and w atoms usually are disordered over all six metal sites. few other small w/v com- plexes are known with n- and o-donor ligand environments: in [l′o(h o)v iv(μ-o)wvio l] + (l = , , -triazacyclononane, l′ = , , -trimethyl-l), vn o and wn o moieties are µ-oxo- bridged, in [v o (μ-ome) (μ-wo ) ( , ′-di-tert-butyl- , ′-bi- pyridine) ], two vn o units are bridged by two wo groups. after identifying a {v w }-type extended keggin structure under solvothermal conditions at high ph (ca. ) in the pres- ence of tris( -aminoethyl)amine (tren), we now were able to isolate [(v(dien)) w o ]· h o ( ) and [(v(dien)) w o ]· h o ( ) (dien = diethylenetriamine, c h n ) under similar con- ditions, where a higher reactant v : w ratio ( : vs. : ) appears to favor a smaller w nuclearity.‡ the crystal structures feature rare vn o and vn o moieties interconnected by edge-sharing wo octahedra (fig. ). compound crystallizes in the triclinic space group p ̄ (table s †) with all atoms located on general positions. a w o core composed of two edge-sharing wo octahedra con- nects to two von moieties (vanadyl-bidentate diene com- plexes) via three µ-o sites, and edge-sharing to two von units (vanadyl-tridentate fac-dien complexes). the four v sites form a planar rhomboid (v⋯v: . Å and . Å, v–v–v: . °). the n⋯n distances in the vn o octahedron are . , . , and . Å, and the n–n–n angle amounts to °. vanadium dien complexes are rare, with only two corresponding entries, all of tridentate fac conformation, in the csd. in , v–n bonds in vn o and vn o ( . ( )– . ( ) Å) exhibit a slight elongation of one v–n bond (v –n , fig. s †), caused by the trans effect. the v–o bonds ( . ( )– . ( ) Å) show the typical short vanadyl vvo bonds ( . ( ) and . ( ) Å). a database analysis (csd) of compounds containing octahedral vn o or vn o units yielded a slightly smaller mean value around . Å. the w–o bonds fall into four groups: . ( ) Å (oterm), . ( )– . ( ) Å (μ -o), . ( ) Å (μ -owv ), and . ( ) Å (μ -ow v), all typical for polyoxotungstates. in , fig. combined polyhedral/ball-and-stick plots of the cluster mole- cules in (a) and (b). wo : grey octahedra, o: red, n: blue, c: black, v: yellow spheres. terminal vvo vanadyl bonds are emphasized in red. h positions omitted for clarity. †electronic supplementary information (esi) available: experimental, crystallo- graphical and structural details, optical properties and thermal stability data. ccdc and . for esi and crystallographic data in cif or other electronic format see doi: . /c dt k ainstitut für anorganische chemie, christian-albrechts-universität zu kiel, kiel, germany. e-mail: wbensch@ac.uni-kiel.de binstitut für anorganische chemie, rwth aachen university, aachen, germany. e-mail: paul.koegerler@ac.rwth-aachen.de cinstitut für chemie und biochemie der freien universität, berlin, germany this journal is © the royal society of chemistry dalton trans., , , – | o pe n a cc es s a rt ic le . p ub li sh ed o n j un e . d ow nl oa de d on / / : : . t hi s ar ti cl e is l ic en se d un de r a c re at iv e c om m on s a tt ri bu ti on -n on c om m er ci al . u np or te d l ic en ce . view article online view journal | view issue www.rsc.org/dalton http://crossmark.crossref.org/dialog/?doi= . /c dt k&domain=pdf&date_stamp= - - http://creativecommons.org/licenses/by-nc/ . / http://creativecommons.org/licenses/by-nc/ . / http://dx.doi.org/ . /c dt k http://pubs.rsc.org/en/journals/journal/dt http://pubs.rsc.org/en/journals/journal/dt?issueid=dt the [(v(dien)) w o ] complexes are arranged in stacks along [ ] and [ ], and the inter-cluster voids are occupied by crystal water molecules. intra-cluster n–h⋯o and extensive d inter-cluster h bonding interactions stabilize the structure. o term is involved in three relatively strong h bonding con- tacts, which may explain the longer vvo bond, while o term has only one such contact (table s †). bond valence sum (bvs) calculations yield values of . / . for v /v and . for the unique w atom, in line with the formal oxidation states v + and w + in . compound crystallizes in the monoclinic space group p /n (table s †) with all unique atoms being located on general positions. here, the cluster core consists of four edge- sharing wo octahedra, forming a distorted w o cubane. four independent vanadyl groups each bind to a tridentate dien ligand in fac conformation and to two o atoms of neigh- boring wo octahedra, resulting in distorted vn o octahedral environments, with two shorter ( . ( )– . ( ) Å) and one longer ( . ( )– . ( ) Å) v–n bond, the latter trans to the terminal vanadyl o site. the resulting v structure is an approximately planar square (v⋯v: . – . Å, root mean square deviation from ideal plane: . Å). the v–o bonds are similar to those in with one short ( . ( )– . ( ) Å, vvoterm) and two longer bonds. the w–o bonds exhibit an identical pattern as in . bvs values (v: . – . ; w: . – . ) support the proposed oxidation states. in , the charge-neutral clusters are arranged in the ( ) plane generating channels along [ ]. a similar arrangement is observed in the ( ) plane, and a second channel type runs along [ ]. as in , neighbored clusters are interlinked by n– h⋯o interactions, in addition to extensive h bonding to the crystal water molecules present in these channels. the magnetic properties of and are represented in fig. as χmt vs. t and mm vs. b plots. for , the ambient tempera- ture ( k) value of χmt is . cm k mol− at . t. this value lies within the range . – . cm k mol− expected for four non-interacting viv centers. upon cooling χmt continu- ously increases up to a maximum of . cm k mol− at k, and subsequently drops off sharply down to . cm k mol− at . k. at . k, the molar magnetization mm as a function of the applied field b shows an inflection point at ca. . t reveal- ing the presence of minor antiferromagnetic exchange inter- actions (the inflection point here indicates a change of the total spin ground state). modeling the magnetic properties of utilized the computational framework condon, employing a “full model” hamiltonian, and assumed four identical v(iv) centers in a c v-symmetric ligand field, reflecting the pro- nounced tetragonal distortion typical for vanadyl groups. five heisenberg-type exchange interaction pathways between nearest-neighbor v(iv) sites (fig. , inset) are characterized by three independent exchange parameters j (v–o–v and v–o– wvi–o–v), j (v–o–w vi–o–v) and j ( × v–o–w vi–o–v). the o–wvi–o bridges here efficiently mediate the coupling via the extended, unoccupied w d orbitals. for fitting purposes, the standard spin–orbit coupling constant ζ d = cm − is taken as a constant, and all states of a d electron configur- ation are accounted for in the calculation of single ion (vanadyl) effects and heisenberg exchange interactions (“− j” notation), i.e. considering in total states. finally, we con- sider the mean-field approach for potential inter-molecular interactions in the solid-state lattice. the least-squares fit (rela- tive root mean squared error, sq = . %) yields the ligand field parameters (wybourne notation) b = cm − , b = cm− , b = cm − , the exchange interaction para- meters j = + . cm − , j = – . cm − , j = + . cm − , and the mean-field interaction parameter zj′ = + . cm− . the ligand field parameters bkq describe a ligand field characterized by strong tetragonal distortion generating a well-isolated kramer’s ground state doublet separated from the first excited state by more than cm− , reconfirming the almost spin- like behavior of the vanadyl groups. the exchange interaction parameters show predominant ferromagnetic exchange, and the additional antiferromagnetic exchange pathways yields a ground state characterized by stotal = , slightly separated (approx. cm− ) from the first excited stotal = state, translat- ing into mm ≈ . naµb as reflected by the inflection point in fig. magnetic data of compounds (top) and (bottom), and coup- ling schemes. χmt vs. temperature t at . t; insets: molar magnetization mm vs. applied field b at . k. open circles: experimental data, red solid lines: least-squares fit. communication dalton transactions | dalton trans., , , – this journal is © the royal society of chemistry o pe n a cc es s a rt ic le . p ub li sh ed o n j un e . d ow nl oa de d on / / : : . t hi s ar ti cl e is l ic en se d un de r a c re at iv e c om m on s a tt ri bu ti on -n on c om m er ci al . u np or te d l ic en ce . view article online http://creativecommons.org/licenses/by-nc/ . / http://creativecommons.org/licenses/by-nc/ . / http://dx.doi.org/ . /c dt k the mm vs. b curve. inter-cluster interactions are almost negligible. the low-field χmt value of at k of . cm k mol− falls into the expected range for four non-interacting viv centers. upon cooling χmt increases sharply below ca. k, reaching . cm k mol− at . k. at . k, mm is linear in b up to tesla, and indicates saturation for fields larger than t at approximately mm = naμb, i.e. pointing to an stotal = ground state, i.e. in line with dominant ferromagnetic exchange interactions in . in analogy to the analysis of except for the coupling scheme (four v–o–w–o–v pathways characterized by a single exchange energy j), the least-squares fit (sq = . %) yields b = cm − , b = cm − , b = cm− , j = + . cm− , and the mean-field interaction parameter zj′ = + . cm− . as for , the ligand field parameters here correspond to a strong tetragonal distortion of the v ligand field, generating a well-isolated (ca. cm− ) kramer’s ground state doublet. note that the common v coordination geometry in is significantly different from (two slightly different site geometries), resulting in different ligand field parameters. the positive j reveals small ferro- magnetic nearest-neighbor coupling in . the ground state of amounts to stotal = , consistent with the observed saturation value of mm ≈ . naμb. as for , inter-cluster coupling in is almost negligible. compound is soluble in water ( . mmol l− ), while the solubility of is extremely low. positive-mode electrospray ionization of a µm water solution of results in an esi mass spectrum exhibiting the intact cluster as the singly and doubly protonated species at m/z = und (fig. ). the base peak of the spectrum can be assigned to [(v(dien)) w o ] + which is most likely formed by elimination of h o upon protonation of the cluster. measurements were performed shortly after preparation of the sample solution in degassed h o as the cluster complex was only stable in solu- tion over a period of minutes. in summary, we infer from the two title compounds that the molecular growth of polyoxotungstates at ph ca. appears to be impeded by coordination of vo(dien) + groups and the associated decrease in negative molecular charge, effectively stopping at {v w } and {v w } nuclearities. com- parison to species formed at similar conditions such as the {v w }-type polyanion emphasizes the crucial role of the employed polyamines. these clusters are among the smallest known heterometal polyoxometalates and as such demonstrate the utility of polydentate ligands such as dien in the isolation of novel polyoxometalates structures. to our great surprise, the resulting exchange pathway geometries allow for ferromagnetic coupling between neighboring vanadyl groups, in stark contrast to the usually strongly antiferromagnetic coupling present in larger vanadato-polyoxometalates featuring similar viv–o–mvi– o–viv motifs such as the {mvi v } keplerate polyanions. notes and references ‡reaction of mmol nh vo and mmol wo ·h o in a mixture of ml con- centrated diethylentriamine and ml water in a sealed glass tube at °c afforded green rod-shaped crystals of after d ( % yield based on v). orange block-shaped crystals of formed under otherwise identical conditions with mmol nh vo and mmol wo ·h o ( % yield based on v). ccdc ( ) and ( ). (a) o. oms, a. dolbecq and p. mialane, chem. soc. rev., , , ; (b) k. y. monakhov, w. bensch and p. kögerler, chem. soc. rev., , , ; (c) a. proust, r. thouvenot and p. gouzerh, chem. commun., , ; (d) a. müller, p. kögerler and h. bögge, struct. bonding, , , . (a) r. finkener, ber. dtsch. chem. ges., , , ; (b) a. rosenheim and h. jahn, ber. dtsch. chem. ges., , , ; (c) c. friedheim, z. anorg. chem., , , . c. m. flynn and m. t. pope, inorg. chem., , , . (a) c. m. flynn and m. t. pope, inorg. chem., , , ; (b) c. m. flynn and m. t. pope, inorg. chem., , , . (a) l. ouahab, s. golhen, s. triki, a. Łapinski, m. golub and r. swietlik, j. cluster sci., , , ; (b) w. huang, l. todaro, l. c. francesconi and t. polenova, j. am. chem. soc., , , ; (c) h. driss, r. thouvenot and m. debbabi, polyhedron, , , ; (d) j.-h. son and y.-u. kwon, inorg. chem., , , ; (e) p. t. ma, c. f. yu, j. w. zhao, y. q. feng, j. p. wang and j. y. niu, j. coord. chem., , , ; (f) x. wang, b. zhou, fig. esi-q-tof-hrms spectrum of compound ( µm in h o, top); experimental isotopic pattern of dication at m/z and calculated isotopic pattern of [(v(dien)) w o ] +. dalton transactions communication this journal is © the royal society of chemistry dalton trans., , , – | o pe n a cc es s a rt ic le . p ub li sh ed o n j un e . d ow nl oa de d on / / : : . t hi s ar ti cl e is l ic en se d un de r a c re at iv e c om m on s a tt ri bu ti on -n on c om m er ci al . u np or te d l ic en ce . view article online http://creativecommons.org/licenses/by-nc/ . / http://creativecommons.org/licenses/by-nc/ . / http://dx.doi.org/ . /c dt k c. zhong and m. ji, cryst. res. technol., , , ; (g) c. wang, l. weng, y. ren, c. du, b. yue, m. gu and h. he, z. anorg. allg. chem., , , ; (h) y. xu, j.-q. xu, g.-y. yang, t.-g. wang, y. xing, y.-h. lin and h.-q. jia, acta crystallogr., sect. c: cryst. struct. commun., , , . u. bossek, p. knopp, c. habenicht, k. wieghardt, b. nuber and j. weiss, j. chem. soc., dalton trans., , . s. kodama, a. nomoto, s. yano, m. ueshima and a. ogawa, inorg. chem., , , . m. rasmussen, c. näther, j. van leusen, p. kögerler and w. bensch, eur. j. inorg. chem., , . 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(a) j. van leusen, m. speldrich, h. schilder and p. kögerler, coord. chem. rev., , – , ; (b) m. speldrich, h. schilder, h. lueken and p. kögerler, isr. j. chem., , , . j. s. griffith, the theory of transition-metal ions, cambridge university press, cambridge, . p. kögerler, b. tsukerblat and a. müller, dalton trans., , , . communication dalton transactions | dalton trans., , , – this journal is © the royal society of chemistry o pe n a cc es s a rt ic le . p ub li sh ed o n j un e . d ow nl oa de d on / / : : . t hi s ar ti cl e is l ic en se d un de r a c re at iv e c om m on s a tt ri bu ti on -n on c om m er ci al . u np or te d l ic en ce . view article online http://creativecommons.org/licenses/by-nc/ . / http://creativecommons.org/licenses/by-nc/ . / http://dx.doi.org/ . /c dt k button : the beauty of outreach when the proposal was funded, i offered to help set up and supervise the activities—simple experiments that explored basic concepts such as light and energy using balloons, plastic bottles, batteries, and other everyday materials. with no experi- ence in this kind of environment, i didn’t know quite what to expect. as i worked with the children, i was in- terested to discover that they gained as much from their interactions as from the content of the activities. their excitement grew as they devel- oped a community by collaborating or, more often, engaging in friendly competition. i found that i greatly enjoyed facilitating this kind of fun and socializing through physics. after hearing about my work on these edutainment activities, the director of the physics department asked me to coordinate our departmental outreach pro- gram’s main project, which aims to enrich physics education for students in their final years of high school. i was grate- ful for this opportunity, which allowed me to make outreach part of my professional life. i have also found, unexpectedly, that it has been even more important on a personal level. it has helped me find a new level of community and connec- tion with students, which has reignited my own excitement about physics and my appreciation of the relationships that can emerge from sharing in the scientific inquiry process. working with the graduate students involved in the proj- ect has shown me how collaboration can create a vibrant, creative community, which simultaneously makes the work more fun and leads to a better final result. when i started on the project, graduate students in the department merely helped conduct established educational activities, but soon, on their own initiative, many of them started to propose new activities related to their research. in turn, we started to work more as a team. now, our meetings feature lively discussions about the status of the outreach project and possible directions for future development. everyone con- tributes, leading to warm, meaning- ful personal interactions. seeing the students thrive in this environment has made me realize that our out- reach program serves not merely to explain scientific concepts, but also to share the idea that participating in science is a positive, enriching personal experience. a few months ago, when the new director of the department asked me to take on the responsibility for the entire program, i accepted enthusiastically, effectively choos- ing outreach as my primary activity. i still plan to continue my research, because these activities are comple- mentary and i like the way they complete my work life, but i know that doing both outreach and research will be a chal- lenge. nonetheless, i’m confident that it will be worthwhile, and i look forward to continuing to develop our outreach program. i want to engage the high school students as well as educate them so that they can experience the joy of shar- ing their scientific enthusiasm in a communal environment. it all started for fun, but in just a couple years, my work life has completely changed. now, when school students ask for advice about pursuing a career in science, i tell them that the beauty of science is engagement and collaboration with a diverse group of individuals. thanks to outreach, i rediscovered this beauty. ■ pierfrancesco riccardi is a researcher at the university of calabria in italy. he thanks the students and postdocs involved in the progetto lauree scientifiche. send your career story to scicareereditor@aaas.org. “it has helped me find a new level of community and connection.” the beauty of outreach a fter about years as an academic researcher in experimental condensed matter physics, i got involved in outreach quite by chance. it happened a couple years ago, when some friends were writing a proposal for their company to run “edutainment” activities for the children in our town. teaching at the university level had been an important part of my job for years, but i had never been involved in anything like what they were proposing. nonetheless, it sounded like fun, so i suggested a partnership between their company and my university’s physics department. this is how i discovered the joy of outreach, which has ended up taking my career in an unexpected direction. by pierfrancesco riccardi il l u s t r a t io n : r o b e r t n e u b e c k e r sciencemag.org s c i e n c e w o r k i n g l i f e november • vol issue da_ workinglife.indd / / : am published by aaas o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/ the beauty of outreach pierfrancesco riccardi doi: . /science. . . ( ), . science article tools http://science.sciencemag.org/content/ / / permissions http://www.sciencemag.org/help/reprints-and-permissions terms of serviceuse of this article is subject to the is a registered trademark of aaas.sciencescience, new york avenue nw, washington, dc . the title (print issn - ; online issn - ) is published by the american association for the advancement ofscience copyright © , american association for the advancement of science o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/content/ / / http://www.sciencemag.org/help/reprints-and-permissions http://www.sciencemag.org/about/terms-service http://science.sciencemag.org/ biomed centralbmc genomics ss open acceresearch article enhancer trapping in zebrafish using the sleeping beauty transposon darius balciunas , ann e davidson , , sridhar sivasubbu , spencer b hermanson , zachary welle and stephen c ekker* address: arnold and mabel beckman center for transposon research, department of genetics, cell biology and development, university of minnesota, - jackson hall, church st se, minneapolis, mn- , usa and molecular, cellular, developmental biology and genetics graduate program, university of minnesota, usa email: darius balciunas - balci @umn.edu; ann e davidson - david @umn.edu; sridhar sivasubbu - sivas @umn.edu; spencer b hermanson - herma @umn.edu; zachary welle - well @umn.edu; stephen c ekker* - ekker @mail.med.umn.edu * corresponding author abstract background: among functional elements of a metazoan gene, enhancers are particularly difficult to find and annotate. pioneering experiments in drosophila have demonstrated the value of enhancer "trapping" using an invertebrate to address this functional genomics problem. results: we modulated a sleeping beauty transposon-based transgenesis cassette to establish an enhancer trapping technique for use in a vertebrate model system, zebrafish danio rerio. we established lines of zebrafish with distinct tissue- or organ-specific gfp expression patterns from founders that produced gfp-expressing progeny. we have molecularly characterized these lines and show that in each line, a specific gfp expression pattern is due to a single transposition event. many of the insertions are into introns of zebrafish genes predicted in the current genome assembly. we have identified both previously characterized as well as novel expression patterns from this screen. for example, the et line harbors a transposon insertion near the mkp locus and expresses gfp in the midbrain-hindbrain boundary, forebrain and the ventricle, matching a subset of the known fgf -dependent mkp expression domain. the et line, in contrast, expresses gfp specifically in caudal primary motoneurons due to an insertion into the poly(adp- ribose) glycohydrolase (parg) locus. this surprising expression pattern was confirmed using in situ hybridization techniques for the endogenous parg mrna, indicating the enhancer trap has replicated this unexpected and highly localized parg expression with good fidelity. finally, we show that it is possible to excise a sleeping beauty transposon from a genomic location in the zebrafish germline. conclusions: this genomics tool offers the opportunity for large-scale biological approaches combining both expression and genomic-level sequence analysis using as a template an entire vertebrate genome. background human, mouse and rat genomes likely have less than genes each [ - ]. this is only two to three times as many genes as in caenorhabditis elegans and drosophila melanogaster, and only six times as many as saccharomyces cerevisiae [ - ]. the increased complexity of vertebrates published: september bmc genomics , : doi: . / - - - received: august accepted: september this article is available from: http://www.biomedcentral.com/ - / / © balciunas et al; licensee biomed central ltd. this is an open-access article distributed under the terms of the creative commons attribution license (http://creativecommons.org/licenses/by/ . ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. page of (page number not for citation purposes) http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . / - - - http://www.biomedcentral.com/ - / / http://creativecommons.org/licenses/by/ . http://www.biomedcentral.com/ http://www.biomedcentral.com/info/about/charter/ bmc genomics , : http://www.biomedcentral.com/ - / / therefore can not be simply accounted for by a larger gene number. a part of the increased complexity is thought to be accomplished by alternative splicing, rna editing and the use of protein modifications to generate a variety of protein products from a single gene, but everything starts with increased complexity at the level of transcriptional regulation. while promoters are relatively simple and short in yeast, their complexity increases in multicellular organisms, making regulatory sequences ever harder to identify. in humans, enhancer elements can be located over a megabase away from the transcriptional start site [ ]. furthermore, current gene prediction programs used to annotate genomes often fail to correctly identify the ' start site of a transcription unit, making in silico analysis of the regulatory sequences even more complex. to further complicate the matter, enhancer sequences diverge in evo- lution, co-evolving with their respective transcription fac- tors, and often do not work across large evolutionary distances – worm to fly, for example [ ]. this makes infor- mation from non-vertebrate model systems sometimes inapplicable to vertebrate sequences. enhancer detection ("trapping") using insertion site con- text vectors was popularized as a genomics tool in dro- sophila. the first fly enhancer trap vectors were based on the p element transposon and often used the transposase's own promoter fused to the beta-galactosidase reporter gene for enhancer detection [ - ]. several of the enhancer trap lines were shown to express the lacz reporter in cells corresponding to the expression patterns of nearby genes, validating the approach [ , ]. in other work, promoters such as engrailed, fushi tarazu and hsp were successfully developed for enhancer trapping in the fruitfly [ - ]. further modifications to the system included the implementation of a bipartite system with a gal transactivator [ ], green fluorescent protein (gfp) [ ], and even a gfp-lacz fusion protein [ ] as report- ers. in addition to the p element, other transposons such as hobo and piggybac with insertion site preferences dis- tinct from those of the p element have been used in dro- sophila [ , ]. the availability of a variety of transposons, promoters and reporters for enhancer trap- ping in the fruitfly enabled researchers to obtain enhancer trap insertions into a considerable fraction of drosophila genes (reviewed by [ ]) and allows an investigator to choose vectors most suitable for the problem at hand. the ability to excise from a genomic location has been instrumental to the utility of p element based vectors. for mutation-causing insertions, reversion of the mutant phe- notype by p element excision proves that a given insertion causes the mutation. since the mutagenicity of drosophila enhancer trap transposons is not significantly higher than the average % rate obtained with regular p elements, most insertions do not result in a mutation [ ]. in these instances, the p element's ability to induce genomic dele- tions by "imprecise excision" can be used to obtain a mutation in the neighboring gene(s) [ ]. the success of enhancer trapping in drosophila prompted application of this approach in the mouse [ - ]. as was the case in drosophila, the lacz reporter was shown to be expressed in part of the target gene's expression domain [ ]. despite the considerable success of these early exper- iments, enhancer detection as an experimental approach in mouse was not explored further, giving way to different versions of gene traps (for a review, see [ ]). we believe the success of enhancer trapping in drosophila can be largely attributed to the advantages of this experi- mental system over mouse. in drosophila, large numbers of transgenic organisms can be readily generated and screened for gene expression patterns. it is far less practical in the mouse. this is partly due to the availability of effi- cient and precise transgene delivery tools in the fruitfly: the native p element, hobo and piggybac transposons. in contrast, early mouse experiments were carried out by non-facilitated dna transgenesis. this approach is less efficient and prone to induce deletions and other genome rearrangements in the recipient locus, as noted in the first published mouse enhancer trap locus [ , ]. the com- pact nature of the drosophila genome also contributed to the success of enhancer trapping, making the path from an enhancer trap insertion to the identification of the affected gene straightforward, especially once the dro- sophila genome was sequenced. the zebrafish danio rerio is a vertebrate model system that provides many of the advantages found in invertebrates. a few hundred transparent, externally developing embryos can be obtained from a single pair of fish per week. the zebrafish genome is about two-fold smaller than the mouse genome, and its sequencing and annotation are nearing completion. finally, transposon tools for efficient and precise transgene delivery into the zebrafish genome are available. we focused our research on the sleeping beauty (sb) transposon system [ , ]. while not as effi- cient as the highest titer retrovirus used in zebrafish [ , ], the sleeping beauty transposon system offers advantages in expression as well as ease of construction and testing of diverse vectors that can be done using basic molecular biology tools. furthermore, the sb system offers the possibility of transposase-induced excision out of the genome to induce local deletions or to revert possi- ble mutant phenotypes. in this report, we investigated the potential of the sb transposon system for enhancer detection in zebrafish. our results indicate that zebrafish enhancer trap lines with diverse gfp expression patterns can be readily page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / generated using the sb system. most of the obtained lines harbor a single transposon insertion event, facilitating the rapid identification of transposon insertion sites responsi- ble for specific gfp expression patterns. we show that two enhancer trap lines exhibit gfp expression patterns matching the expression patterns of the target genes, and that both expected and novel gene expression patterns can be identified using this genomics tool. we conclude that enhancer trapping using the sleeping beauty transposon system is a viable experimental approach using as tem- plate a vertebrate genome. results the sleeping beauty transposon can detect enhancers in cis we have previously established multiple zebrafish lines using sb transposons with ubiquitous and tissue-specific promoters driving reporter expression [ ]. surprisingly, we did not observe any dependency of the expression pat- tern on the genomic context of the transposon insertion. multiple studies describing insertion-site dependent transgene expression in vertebrates have suggested that many of those events are due to the transgene falling under control of nearby enhancers [ - ]. for enhancer detection approaches it is imperative that the reporter gene be sensitive to neighboring transcriptional regula- tory elements. at least three explanations can be put for- ward to explain the absence of expression patterns in our previous work in zebrafish. first, the sleeping beauty transposons are flanked by relatively large inverted repeats. these repeats might function as silencer elements and not allow for transcriptional regulation across them. second, the promoter we used (xenopus laevis ef α, [ ]) may not be subject to transcriptional regulation by tissue-specific enhancers. third, the expression level from the selected promoter may be too high to be effectively modulated, as enhancer traps usually contain attenuated promoters. to test these hypotheses, we decided to pro- duce an artificial enhancer trapping event by cloning a tis- sue-specific promoter / enhancer just outside the inverted repeats and test for an increase in tissue-specific expres- sion in injected embryos (figure ). we started with the transposon used in our previous work, pt /s ef α-gm , which contains a shortened version of the xenopus laevis ef α promoter driving the gm version of gfp in a pt transposon vector [ ]. we took advantage of the observa- tion that relatively few pt /s ef α-gm injected embryos express gfp in the eye. we added a lens-specific xenopus laevis γ -crystallin promoter [ ] to the pt / s ef α-gm vector, as we had previously shown that this promoter specifically expresses in the lens of injected (f ) and transgenic (f ) zebrafish [ ]. embryos injected with pt /s ef α-gm or γ cry /pt /s ef α-gm were scored for any gfp fluorescence and for eye-specific gfp fluorescence at dpf (figure ). the addition of γ cry to pt /s ef α-gm caused a modest (two-fold) increase in injected embryos showing any gfp fluorescence. in con- trast, the increase in eye-specific gfp expression was ten- fold (figure ). we concluded that at least in this assay, the sleeping beauty inverted repeat sequences do not block transcriptional regulation and that the ef α pro- moter can be subject to transcriptional regulation from external, tissue-specific regulatory sequence elements. promoter truncations and pilot screens we next tested the hypothesis that the absence of expres- sion patterns in our previous work was due to the fact that s ef α is expressed too strongly in transgenic animals. since most successful enhancer traps in drosophila and mice were based on truncated or weak promoters, we decided to attenuate the s ef α promoter by removing sequences upstream of bst i (s ef α) and ecori (s ef α) restriction enzyme sites (figure ). we then co- injected the corresponding transposon constructs with sb transposase mrna to assess germline transmission, expression and enhancer trapping rates. in pilot experi- ments, progeny from over fish were screened with each construct. while overall germline transmission and expression rates were comparable (figure ), there was a difference in the expression patterns of the two constructs in transgenic embryos. most of the transgenic animals generated with pt /s ef α-gm exhibited weak gfp expression, and we could not detect any expression pat- terns (data not shown). in contrast, when pt /s ef α- artificial enhancer trapping with a sleeping beauty transposonfigure artificial enhancer trapping with a sleeping beauty transposon. comparison of gfp expression in embryos injected with pt /s ef α or γcry /pt /s ef α. plasmids are diagramed as cartoons on the top of the picture. the sb transposon's inverted repeats are shown as boxes with open triangles, and the gfp open reading frame is depicted as a grey arrow. the gamma-crystallin promoter/enhancer is shown as a hatched box. dna-injected embryos which sur- vived to dpf were counted and scored for gfp fluores- cence anywhere in the embryo (any gfp) and for fluorescence in the eye (eye gfp), even if there was addi- tional fluorescence elsewhere. the average percentage of embryos positive for particular gfp fluorescence in three independent experiments is shown ± standard deviation. page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / gm was used, most of the gfp-positive fish exhibited fairly strong, ubiquitous expression. closer analysis indi- cated that many of these "ubiquitous" expression patterns were rather unique, with gfp expression often noted to be particularly strong in some tissues, consistent with a tis- sue-specific expression pattern superimposed on a ubiqui- tous expression pattern (data not shown). in most cases, gfp expression segregated as a single integration event, indicating that a tissue-specific expression pattern was not likely being masked by a ubiquitous expression pattern from a different insertion event. a similar phenomenon has been observed with drosophila enhancer traps [ ]. we speculate that in those instances, the gfp expression cassette may have fallen under the control of multiple enhancers – some tissue-specific, some ubiquitous. alter- natively, the ubiquitous expression may stem from the ubiquitous activity of the ef α promoter used in the screen, with tissue-specific enhancers only elevating the expression levels in certain tissues, but not restricting it. we did not consider such expression patterns valuable and did not establish any fish lines with such gfp expres- sion. importantly, one of the founders in the pt /s ef α- gm pilot screen yielded three kinds of gfp expression in its progeny. some were ubiquitously gfp positive, some showed a hatching gland-specific expression profile, and some exhibited both. when three f fish with both ubiquitous and hatching gland specific expression were raised and outcrossed, the two expression patterns exhib- ited independent segregation: % of the embryos were gfp negative, % expressed gfp ubiquitously, % had hatching gland-specific gfp expression, and % had both hatching gland-specific and ubiquitous expression (n = ). independent segregation indicates that the two transposon insertions causing the two expression patterns are unlinked. two independent integration events were confirmed by southern hybridization and inverse pcr (data not shown). the hatching gland-specific gfp expressing embryos were used to establish our first enhancer trap line, et (figure a). we concluded from our pilot screens that pt /s ef α-gm demonstrated the desired properties for potential use in enhancer trapping studies. germline excision of a sleeping beauty transposon insertion we have previously demonstrated the excision of a sleep- ing beauty transposon from the genome in somatic tissues of transposase-injected zebrafish embryos [ ]. we tested if such an excision event could be inherited by examining transposon excision in the germline. embryos homozygous for the et insertion were injected with sb transposase mrna, and while some were used for a somatic excision assay the rest were raised to test for germ- line transmission of an excision event. a pcr reaction on genomic dna from transposase-injected embryos with primers flanking et insertion point produced two bands. a large band corresponded in size to the transposon inser- tion allele, and a small band corresponded to a transpo- son-less allele (data not shown). both cannonical sleeping beauty transposon footprints (atgtcat and atgacat, [ , ]) were obtained upon cloning and sequencing of the smaller band, indicating a transposase-mediated exci- sion and dna repair. fish were screened for germline transmission (see materials and methods), and one was shown to transmit the expected excision footprint. we conclude that the sleeping beauty transposon can be excised from a genomic location in the zebrafish germline. pt /s ef α-gm scale-up screening: % of gfp- expressing integrations yield tissue-specific patterns one tissue-specific expression pattern was recovered from our pilot screen. we sought to recover more patterns and to test if enhancer detection in zebrafish is amenable to scale-up. to that end, we co-injected zebrafish ef α promoter truncations and endogenous enhancer trap screeningfigure ef α promoter truncations and endogenous enhancer trap screening. a diagram of the s ef α pro- moter [ , ]. restriction enzyme sites are shown on top as single letters. s is sphi, n is nhei, b is bst i and r is ecori. g/c, g and c rich box. sp , sp -like site. tata, tata box. numbering below is relative to the first t of the tata box. the table below the diagram shows the results of the pilot and scale-up (*) screens. transgenesis and expression rates are shown, non-expressing transposon insertions were not scored. transgenesis and expression rate from scale-up screen (#) is an underestimate since many founders were screened by incross and crosses from doubly transgenic founders were scored as a single transmission event (see text). - - tatasp g/c sp rbs, n tatasp sp tatasp s ef aa s ef a s ef a transposon screened transgenesis recovered and expression patterns n n % n % pt /s ef a/gfp % % pt /s ef a/gfp % % pt /s ef a/gfp * %# % - page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / enhancer trap lines exhibit a variety of unique gfp expression patternsfigure enhancer trap lines exhibit a variety of unique gfp expression patterns. (a). lateral view of gfp expression in enhancer trap line (et ) at hours post fertilization (hpf). (b) et at – somite stage. (c) et at hpf. (d) et at hpf. (e) et at hpf. (f) et at hpf. (g) et at hpf. (h) et at hpf. (i) ventral view of et at dpf. (j) lateral view of et at hpf. (k) dorsal view of et at hpf. (l) lateral view of et at hpf. in all panels, anterior is to the left. see text for details. page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / embryos with the pt /s ef α-gm and sb transposase mrna mix. embryos survived to day for scoring, of which were mosaic gfp positive and were selected to be raised. survived to adulthood and were screened for germline transmission of gfp expression, primarily by sibling incrossing. this approach provided a lower esti- mate of the transgenesis and expression rate because it does not distinguish instances were both parents are transgenic. in this screen, at least of the founder fish produced gfp-expressing progeny resulting in a mini- mum estimate of a % transgenesis rate. the actual transgenesis rate is closer to % because most of the fish were screened by incross, and if a pair produced gfp- expressing progeny, only one parent was counted as a transmitter. eight of the gfp-expressing fish displayed distinct gfp expression patterns (figure ). together with the pilot screen, tissue-specific expression lines were obtained from transgenic founder fish ( %) using the pt /s ef α-gm transposon. recovered expression patterns label a diverse array of tissues during embryogenesis gfp expression in et can be first observed in the polster region at – somite stage (not shown). the expression is very pronounced between and hours post-fertiliza- tion (hpf), when it marks the hatching gland (figure a). expression disappears as the hatching gland is resorbed. line et represents a pattern with the earliest onset of expression. anterior localization of gfp in the dien- cephalon is detected by – somite stage in this line (figure b). extremely bright anterior expression persists in the ventral diencephalon (figure c) and by days post-fertilizations (dpf) is restricted slightly more poste- rior in the midline. the onset of expression for et is hpf with a bilateral expression pattern in cranial sensory ganglia that remains strong until dpf and is undetectable by dpf. this anterior expression in et seems to label the lateral line ganglia both anterior and posterior to the otic vesicle (figure d), however, no expression is detected in the lateral line in the trunk. in et a single bilateral patch of strong gfp expression in the hyoid arch is observed by hpf (figure e), that by hpf marks a more anterior location in the embryo (figure f). expres- sion in this line is greatly diminished by dpf and is undetectable by dpf. strong gfp expression is observed in et by hpf as a bilateral expression pattern consist- ing of two distinct patches in a subset of cranial sensory ganglia/placodes (figure g). the expression weakens by dpf and is undetectable by dpf. gfp expression in et begins weakly in the midbrain-hindbrain boundary (mhb) at – somites with the most pronounced expression in the anterior side of the mhb detected by hpf (figure h). robust expression in the heart is first detected at around hpf and remains ventricle-specific through dpf (figure i), even though expression in the brain is no longer restricted to the mhb. gfp expression in et is already localized by – somites and remains strong in the telencephalon, and posterior side of the mhb through hpf (figure j). by dpf the localized anterior expression is undetectable over autofluorescence, however, caudal expression appears to be enhanced in the dorsal neural tube. the onset of expression in et occurs around hpf and is difficult to detect by dpf. at – hpf (figure k, l), three distinct expression domains are apparent in the telencephalon, diencephalon and hind- brain of et . the et line expresses gfp specifically in the motoneurons we analyzed the et line in detail because of the highly specific expression of gfp in these fish. gfp expression was first observed at the somite stage, when bilateral cells in the spinal cord of the anterior somites become gfp positive (figure ). at later stages, multiple cells per somite become gfp positive, either due to continued expression of gfp mrna or due to segregation of gfp to daughter cells. gfp expression follows the wave of somi- togenesis, with the posterior-most somites lagging in gfp expression. at about hours, ventrally-projecting axons become visible by gfp fluorescence. later yet a pattern of nodes appears along the axons (figure ). based on the position of neuronal cell body and the axonal trajectory, we conclude that caudal primary motoneurons express gfp in this line [ ]. to our knowledge, this is the first gene to be specifically expressed only in this subpopula- tion of motoneurons. we therefore sought to identify the locus tagged by this transposon insertion. southern analysis indicated that there is a single transpo- son insertion in this line, and it is linked to gfp expres- sion (figure ). inverse pcr identified a transposase- mediated insertion into a ta dinucleotide at position on contig ctg (zebrafish genome assembly zv ). the insertion occurred into a genescan-predicted gene. further analysis indicated that the genescan-pre- dicted gene actually consists of parts of at least two differ- ent genes, myoferlin and poly(adp-ribose) glycohydrolase (parg). the insertion located in the parg part of the predicted transcript, nucleotides from an exon just upstream of the parg catalytic site. to confirm that the transposon insertion into the parg gene induced gfp expression in primary motoneurons, we pre- pared genomic dna from both gfp positive and gfp negative embryos from an independent outcross, and we conducted a pcr with neuroins-f and neuroins-r primers specific to the flanking sequences. in gfp nega- tive embryos, a . kb band corresponding to wild type locus is noted. in gfp positive embryos, the same band is seen in addition to a larger band of approximately . kb, corresponding to a locus with transposon insertion page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / (figure ). since the inverse pcr and confirming pcr was performed on dna from different batches of embryos, we can exclude the possibility of dna contamination or fish husbandry error and conclude that the enhancer trap transposon insertion into the parg gene causes gfp expression in caudal primary motoneurons. gfp expression in et line matches the expression of the endogenous parg gene poly(adp-ribosyl)ation is a protein modification that is extensively studied at the biochemical level and is associ- ated with changes in dna replication, recombination, repair and transcription [ ], for a review, see [ ]. recently poly(adp-ribosyl)ation was demonstrated to have a role in long term memory in the sea slug aplysia [ ]. most organisms have multiple genes for poly (adp- ribose) polymerases but only a single known gene for poly (adp-ribose) glycohydrolase [ ]. parg activity is noted to be expressed in many cell lines, among them neuronal [ - ], but the tissue specificity of parg expression dur- ing embryogenesis has not been reported for any organ- ism. to test if the pt /s ef α-gm enhancer trap recapitulates the expression pattern of the endogenous parg gene, we conducted whole mount in situ hybridiza- tion on et outcross embryos to compare parg and gfp reporter expression (figure ). in situ hybridization visu- alizes axonal cell bodies, the position of which appears indistinguishable with both parg and gfp probes. we therefore conclude that gfp mrna expression in this enhancer trap line faithfully recapitulates the expression of the zebrafish parg gene during embryogenesis. molecular analysis of other enhancer trap lines identifies target genes we characterized insertion events in other enhancer trap lines. gfp positive f or f fish were outcrossed, and embryos were sorted into gfp positive and gfp negative pools. genomic dna was prepared from each pool, and southern analysis was conducted to assess transposon copy number and linkage to the gfp expression pattern. in all lines except et (see above), a single gfp expres- sion-linked transposon insertion event was detected by southern hybridization. we then conducted inverse pcr analysis on the dna from gfp positive embryos to the et transgenic fish line expresses gfp in caudal primary motoneuronsfigure the et transgenic fish line expresses gfp in caudal primary motoneurons. gfp expression in et was visualized in motoneurons using a bandpass gfp filter set at various stages of embryonic development. in all panels anterior is to the left. (a) the onset of gfp expression in et line at somite stage. (b) somite stage. (c) hpf. (d, e) hpf. axonal trajecto- ries are visible at and hpf. a b c d e page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / identify the insertion locus. for verification, dna from embryos from an independent outcross was prepared and pcr was run with primers flanking the insertion site to link gfp expression and transposon insertion at a partic- ular locus. verified enhancer trap loci are presented in table . notably, seven of the insertions have occurred into introns of genescan-predicted genes. four of the tagged genes show significant homologies to previously identified genes: parg (see above), mapk upstream kinase-binding inhibitory protein (mbip) [ ], a member of cytochrome p superfamily and nidogen [ ]. the other three tagged predicted genes do not have significant homologies to previously identified genes. in the two lines which have insertions into intergenic regions, trans- posons have integrated less than kb from the nearest predicted transcript. et line has a transposon insertion near mkp locus and matches mkp expression pattern the transposon insertion in et line has occurred into a predicted novel gene (table ). closer investigation of the target locus revealed the presence of a previously charac- terized zebrafish mkp gene within kb of the insertion site. our attempts to amplify the predicted novel candi- date gene from maternal and post-somitogenesis zebrafish cdna libraries using different primer pairs failed, while mkp cdna was readily amplified in parallel pcr reactions (data not shown). this suggests that the novel target gene may be a false prediction by genescan. the mkp gene encodes a dual specificity phosphatase which was cloned as a member of fgf synexpression group and is a negative feedback regulator of fgf signal- ing. mkp is expressed in the midbrain-hindbrain bound- ary, forebrain, tailbud, branchial arches, developing ear, pectoral fin buds and other tissues [ , ]. gfp expres- sion in et line closely mimics mkp mrna expression pattern in hour embryo (figure ). the only significant difference is that gfp expression is stronger in somites and not as bright in the tailbud, even though the tailbud expression becomes brighter at later stages of develop- ment (data not shown). we did not observe gfp expres- sion in the pectoral fin buds, even though we reproduced mkp expression in the fin buds just after after hpf by in situ (data not shown, [ , ]. an intriguing possibility is that mkp expression in pectoral fin buds may be con- trolled by a different enhancer, one we do not detect in this transgenic line. additionally, et expresses gfp in the heart after hpf, and the expression clearly localizes to the ventricle at dpf (figure i). expression of mkp in the heart after hpf was not reported, and we did not conduct in situ hybridization on late pharyngula stage embryos to test for it. however, fgf is expressed in the ventricle of the zebrafish heart at hpf [ ]. taken together, this suggests that gfp expression in et line mimics a subset of the complete expression pattern of the zebrafish mkp gene. discussion in this paper, we describe the first use of enhancer trap- ping, or enhancer detection, as an experimental approach in zebrafish. we show that sleeping beauty transposons can trap enhancers by testing an artificial enhancer trap- ping event in vivo. this approach is likely to also be useful in the construction and testing of other trap vectors: gene ( ' exon) and polya ( ' exon) and other related con- structs. we then constructed two further truncations to the s ef α promoter in the transgenesis cassette [ ] and found one to be particularly suitable for enhancer trap- ping. ten percent ( of ) of gfp-expressing transgenic identification of the transposition event in the et linefigure identification of the transposition event in the et line. (a) the pt /s ef α transposon insertion into zebrafish genome is shown; restriction enzyme sites and primers used for molecular analysis are indicated. transposon ir/dr's are shown as solid boxes with open triangles, and the gfp open reading frame is shown as a grey arrow. genomic dna is shown as a dotted line. n is nsii, e is ecorv. (b) southern blot on et line outcross embryos. dna from gfp positive (lanes and ) and gfp negative (lanes and ) embryos was digested with nsii (lanes and ) or ecorv (lanes and ) and probed with a gfp-specific probe. (c) linkage of the transposon insertion event to gfp expression. primers flank- ing the transposon insertion event (arrows) were used to conduct pcr on dna from gfp positive (lane ) and gfp negative (lane ) embryos from an et outcross different from the one used in (b). lane , λ eco iii marker (fermen- tas inc). b n ee ne a page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / fish generated lines with unique gfp expression patterns. all reagents described in this paper, including the enhancer trap fish strains, are readily available upon request http://beckmancenter.ahc.umn.edu. many of the obtained enhancer trap lines express gfp in the nervous system. this was previously observed with both mouse and drosophila enhancer trap vectors and was speculated to stem from the transcriptional complexity of neural tissue [ , ]. several of our lines also exhibit some level of gfp expression in the eye. at least two expla- nations can be put forward to explain this observation. first, many genes are expressed in the developing eye. thus, the eye expression that we see may reflect expression of the tagged genes in the eye. second, optical properties of the tissues in the eye may permit detection of gfp expression that is lower that what would be required for detection in other tissues. the et line harbors a transposon insertion into the zebrafish gene for poly(adp-ribose) glycohydrolase (parg). we demonstrate that both parg and gfp in et line are expressed in caudal primary motoneurons of hour old embryos. thus, gfp expression in the et line gfp expression in et line embryos is indistinguishable from endogenous parg gene expressionfigure gfp expression in et line embryos is indistinguishable from endogenous parg gene expression. hpf embryos collected from a heterozygous outcross were photographed for gfp fluorescence and sibling embryos were fixed for in situ hybridization. (a) in situ hybridization with parg antisense probe. (b) in situ with gfp antisense probe. (c) visualization of gfp expression in living embryos using a bandpass gfp filter set. (d) the same embryo as in (c) photographed using a bandpass gfp filter set with a low level of bright field illumination to visualize gfp expression in relative position to the somites. page of (page number not for citation purposes) http://beckmancenter.ahc.umn.edu bmc genomics , : http://www.biomedcentral.com/ - / / mimics that of an endogenous gene (parg), indicating that transgene expression is under control of an endog- enous enhancer. a very intriguing question is what the actual trapped enhancer sequence is, how far away from the genomic enhancer the trap can insert and still detect it, and weather artificial enhancer trap approach (figure ) can be used to answer these questions. the et line has a transposon insertion into a predicted novel gene kb downstream of the zebrafish mkp locus. gfp expression in that line closely resembles part of the mkp expression domain, suggesting that the enhancer trap transposon in that line is under control of a subset of mkp enhancer elements. zebrafish enhancer trap lines will be valuable in future developmental genetics studies, be it classical mutagene- sis or morpholino "knockdown" screening [ ]. gfp expression can be used as a sensitive marker for certain tis- sue or cell types. for example, the et line expresses gfp in the hatching gland. the expression of the hgg gene is specific to the polster and hatching gland depends on nodal signaling and is absent in one-eyed-pinhead mutants [ ]. we phenocopied the one-eyed-pinhead mutation by gfp expression in et line matches mkp mrna expressionfigure gfp expression in et line matches mkp mrna expression. (a) gfp fluorescence photograph of an et embryo at hpf. (b) in situ hybridization on hpf wild type embryo using mkp antisense rna probe. table : pt /s ef α-gm transposon insertion events in analyzed enhancer trap lines. trap line sequence insertion location predicted gene et attgtccttagtgtatgtgtttgtgtga chr. none et caaaaagactatatataggaggcttcaa ctg parg et aacgcttaccatgtatgttaataaatgt chr. mbip et tatatcaaaattatatatatgaacgtat chr. cyt. p et gtacatacacatgtacaaatcaacatta ctg novel et attttaaacaaactaagttgaacattac ctg nidogen et atcacagagcatctagcttggatgtgct ctg novel/mkp et tatacaacaaacttatctaacgtgcaat chr. none et tatttaatatatatattatattatatta chr. novel left column, line designation. sequence column, the genomic sequence the transposon has inserted into. the target ta dinucleotide is highlighted in bold. the sequences flanking the left inverted repeat are to the left of the target ta, and sequences flanking the right inverted repeat are to the right of the target ta. lowercase indicates mismatches between an actual sequence read and the current zebrafish genome sequence (assembly zv ). both left and right transposon/genomic dna junctions were sequenced for et , et , et , et and et . only the left junction was read for et , and only the right junction was read for et , et and et . insertion location column, predicted insertion chromosome or contig (zv assembly of the zebrafish genome). predicted gene column, the gene into which the transposon has inserted as annotated in the zebrafish genome assembly zv . novel indicates no significant homologies. gene name indicates significant homology to denoted genes. the predicted integration into an intron of the parg locus for line et was experimentally confirmed (see text). for et , a comparison of the observed expression pattern in this line with that of a known nearby gene (mkp ) indicates this insertion has most likely trapped an enhancer for this gene (fig. , see text). actual sequence reads which were used to determine the genomic location of the transposon insertions were longer than shown in this table and are available upon request. page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / morpholino injection in et homozygotes and observed a complete loss of hatching gland-specific gfp expression (data not shown). while the et line expresses gfp in an organ that can be readily observed using regular light microscopy techniques, other lines visualize tissues that are not nearly as easily morphologically accessible. in par- ticular, the et line visualizes the position of primary motoneuron cell bodies and axonal trajectory. mor- pholinos against known genes or new members of the zebrafish secretome [ ] can be screened for effects on neuronal cell body position or axonal pathfinding in the developing embryos by injection into et line embryos. the et line may provide a fluorescent readout of fgf signaling, thus facilitating the identification of genes involved in that signaling pathway. a further utility offered by the transposon system is the possibility to revert a mutant phenotype or to generate localized deletions by transposon excision [ ]. we suc- cessfully excised the transposon in the germline of the et line, resulting in the expected transposon footprint. it has been shown that excision of the sleeping beauty transpo- son from a plasmid results in local deletions with fairly high frequency which is dependent on the cell type or tis- sue used [ ]. furthermore, the frequency of imprecise excision of sleeping beauty transposons significantly increases in cells with a compromised dna repair pathway [ , ]. it remains to be determined how fre- quently the excision of a sleeping beauty transposon from a genomic location in zebrafish germ line is accompanied by a deletion of flanking genomic dna, and it should be possible to compromise the embryo's dna repair machinery to induce such deletions at a high frequency. our experiments indicate that enhancer detection using sleeping beauty transposons is an easily scalable and efficient experimental technique in zebrafish. obtaining fish with different gfp expression patterns is not the rate limiting step in this process. preliminary molecular analysis of the insertion site is also straightforward using inverse pcr techniques. identification of candidate genes should benefit from the progress in zebrafish genome sequencing and annotation. the main bottleneck step is the detailed biological analysis of gfp and the corre- sponding candidate gene expression profile. in drosophila, the generation of transposase-expressing lines of flies made enhancer detection and p-element mutagenesis in general a mainstream approach. even without a similar gain in efficiency, transposase express- ing fish lines would make enhancer trapping as well as related gene- and poly(a)-trap methodologies even more accessible for high-throughput functional analysis of the vertebrate genome. methods plasmid construction pt /s ef α-gfp (pdb ) was previously published [ ]. to make γ cry/pt /s ef α-gfp (pdb ), a bamhi-hindiii fragment from cry -gfp [ ] containing part of the x. laevis γ-cry promoter was cloned into the ecl ii site of pdb . to produce pt /s ef α-gfp (pdb ), a part of the ef α promoter was deleted from pdb by ligation of the bst i-ncoi and nhei-ncoi fragments of pdb . similarly, the ecori-ncoi and nhei- ncoi fragments of pdb were ligated to produce pt / s ef α-gfp (pdb ). inverse pcr, pcr and primer sequences for inverse pcr experiments, zebrafish genomic dna was digested and ligated as described [ ]. and . microliters of the ligation reaction were used for the first pcr reaction with rp /lp or rp /gfp-r primers in total volume of µl. µl of the first pcr reaction was used as a template for the second (nested) pcr reaction with primer pairs rp /lp or rp /gfp-r , respectively. expand hi fi pcr system (roche) was used for all pcr reactions. a mj research ptc- pcr machine was used for pcr with the following program : °c min., °c sec., °c sec., °c min., cycles. starting at cycle , sec. per cycle was added to the extension time. the same pcr reaction with an annealing temperature °c was used for amplification with primers flanking transposon insertion sites, and for amplification of partial parg cdna from a maternal cdna library. primer sequences are: lp gtgtcatgcacaaagtagatgtcc [ ]; lp actgacttgccaaaactattgtttg; nrp ctaggattaaatgtcaggaattgtg; rp gtgagtt- taaatgtatttggctaag; gfp-r ttcgggcat- ggcactcttg; gfp-r tatgatctgggtatctcgcaa; neuroc -f cgtaaagatgccttgttcagaa; neuroc - r attccgtgactctcctgaaata; neuroins-f ggcttgcatacatgactaatg; neuroins-r gaagact- gaagtcctcaaact; hg - acattgagccactaag- cattg; hg- tgtgtgcacttaaggggcga. mkp -f agtgttgcattctccaggata; mkp -r tgacacagaacttccctgaac; ef a-f ttcctgcag- gtcgactct; gfp-r gtgtaatcccagcagctg. information about other primers is available from the authors upon request. in situ hybridization a partial sequence for the zebrafish poly(adp-ribose) gly- cohydrolase cdna was amplified using primers neuroc - f and neuroc -r and cloned using a topo ta cloning kit (invitrogen) to make pdb . to make antisense rna probe, pdb was digested with spei and transcribed with t rna polymerase (promega) and dig labeling kit (roche). gfp probe was made by amplifying gfp with base pairs of ef α promoter from pt /s ef α-gm using page of (page number not for citation purposes) bmc genomics , : http://www.biomedcentral.com/ - / / primers ef a-f and gfp-r , and cloning it into topo ta cloning kit resulting in pss . pss was linearized with spei and transcribed with t rna polymerase using dig labeling kit. to make mkp antisense probe, mkp cdna was amplified from maternal cdna library with primers mkp -f and mkp -r and cloned into topo ta cloning kit to produce pdb . the plasmid was linear- ized with spei and transcribed with t polymerase using dig labeling kit. screening for germline transmission of sleeping beauty transposons embryos injected with sb transposase mrna and trans- poson dna mix were raised as described [ , ]. in pilot screens, adult fish were outcrossed to brass for ease of hus- bandry. all collected embryos were screened for gfp expression at day post fertilization (dpf) and dpf. we set an arbitrary embryo cutoff for screening, meaning that if less that embryos were obtained from a founder, an additional cross was set up and to obtain additional embryos for screening. analysis of transgenesis data from pilot screens indicated that % of transgenic lines would have been missed if cutoff was set at embryos, and this less stringent coverage protocol was used in scale up screen. also, we decided to limit screening to dpf since none of the transgenics would have been missed in the pilot screens without the dpf screening. transposon excision in the germline homozygous et embryos were injected with sb trans- posase mrna, raised and screened for loss of hatching gland specific gfp expression, or for a change in the gfp expression pattern. twenty six fish were screened (r , for remobilization), and gave gfp negative embryos, with an additional giving ubiquitously gfp positive embryos, suggesting that germline remobilization events may have occurred in as many as % of transposase injected embryos. ubiquitous gfp positive embryos (one in each of the two r ) did not survive. of the two r 's that gave gfp negative embryos, one gave mosaic hatching gland expression in the next generation. pcr with trans- poson specific and flanking primers did not show any changes in the locus. the second r produced embryos that were gfp negative from the total of embryos obtainted. an r adult was outcrossed, embryo dna was prepared, and pcr with primers hg - and hg - was conducted. the resulting pcr fragment was cloned using pcr topo cloning kit (invitrogen). plasmids were sequenced using m forward primer, and one clone with a transposon footprint was identified. to confirm that it was not due to pcr contamination, a second clutch of embryos was obtained, the procedure was repeated, and the same footprint was obtained (data not shown). authors' contributions the experiments described in this paper were planned, conducted and analyzed as a joint effort between the authors. in particular, db, ad, sh and zw contributed to fish screening, line establishment and to scientific descrip- tions of these lines, db and ss to molecular analysis, ad and db to gfp expression and in situ analysis. db designed and built the transposons used in this study and was responsible for drafting the manuscript for publica- tion. se conceived and supervised the study and edited the manuscript. all authors read and approved the final manuscript. acknowledgements we thank paul phelps, sandra leo, amanda mahoney and tessa hodapp for help with fish screening, and aubrey nielsen, rachel bowers, dan carlson and pat cliff for fish maintenance and perry hackett for critical reading of the manuscript. we thank all members of the arnold and mabel beckman center for transposon research for valuable discussions. this research was supported by the arnold and mabel beckman foundation and the national institutes of health (da ). references . lander es, linton lm, birren b, nusbaum c, zody mc, baldwin j, devon k, dewar k, doyle m, fitzhugh w, funke r, gage d, harris k, heaford a, howland j, kann l, lehoczky j, levine r, mcewan p, mckernan k, meldrim j, mesirov jp, miranda c, morris w, naylor j, raymond c, rosetti m, santos r, sheridan a, sougnez c, stange- thomann n, stojanovic n, subramanian a, wyman d, rogers j, sul- ston j, ainscough r, beck s, bentley d, burton j, clee c, carter n, coulson a, deadman r, deloukas p, dunham a, dunham i, durbin r, french l, grafham d, gregory s, hubbard t, humphray s, hunt a, jones m, lloyd c, mcmurray a, matthews l, mercer s, milne s, mullikin jc, mungall a, plumb r, ross m, shownkeen r, sims s, waterston rh, wilson rk, hillier lw, mcpherson jd, marra ma, mardis er, fulton la, 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/gene. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . /mcb. . . - . http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . /mcb. . . - . http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . /mcb. . . - . http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . /s - ( ) - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . /s - ( ) - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= . /s - ( ) - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids= http://www.biomedcentral.com/ http://www.biomedcentral.com/info/publishing_adv.asp http://www.biomedcentral.com/ abstract background results conclusions background results the sleeping beauty transposon can detect enhancers in cis promoter truncations and pilot screens germline excision of a sleeping beauty transposon insertion pt /s ef a-gm scale-up screening: % of gfp- expressing integrations yield tissue-specific patterns recovered expression patterns label a diverse array of tissues during embryogenesis the et line expresses gfp specifically in the motoneurons gfp expression in et line matches the expression of the endogenous parg gene molecular analysis of other enhancer trap lines identifies target genes et line has a transposon insertion near mkp locus and matches mkp expression pattern table discussion methods plasmid construction inverse pcr, pcr and primer sequences in situ hybridization screening for germline transmission of sleeping beauty transposons transposon excision in the germline authors' contributions acknowledgements references wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty 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beautiful? small enterprise, aid and employment in africa john page the brookings institution and måns söderbom university of gothenburg revised final draft february abstract aid providers often describe small firms as “job creators”. but what types of jobs do they create? drawing on enterprise survey data for nine african countries and panel data for ethiopia we find that small and large formal sector firms create similar numbers of net jobs. small firms, however, have much higher turnover of employment and pay persistently lower wages. to create more ‘good’ jobs aid should target the constraints to the growth of firms of all sizes. improving the ‘investment climate’ and new programs to increase firms’ capabilities—through for example management training—offer greater prospects for employment creation. keywords: aid, small enterprise, employment, firm exit, africa jel classification: j , o , o , o is small beautiful? small enterprise, aid and employment in africa john page and måns söderbom . introduction small firms are big business in the aid industry. why? in a word: jobs. there are an estimated - million formal and informal micro, small and medium enterprises (msmes) in the developing world, employing about per cent of all workers. only million to million of these firms are formal smes ( to employees). more than per cent are either formal enterprises with fewer than employees or enterprises that are not formally registered (mckinsey ). not surprisingly, in the wake of the arab spring small firms have increasingly come to be viewed by the donor community as “job creators” for the young and growing populations of africa, the middle east, and asia. at the spring meetings of the imf and world bank, andrew mitchell, then the uk secretary of state for international development, declared that “small and medium enterprises are a vital engine of job creation in developing countries.” mitchell is not alone. the european union recently asserted, “for developing countries, the expansion of the private sector, notably msmes is a powerful engine of economic growth and the main source of job creation (emphasis in original)” (eu ). in this paper we ask whether donor’s confidence that aid to msmes will help to create “good” jobs in africa —jobs capable of sustaining employment and paying decent wages—is supported by the evidence. following this introduction, section describes the current state of donor assistance to msmes. there are more than public and private investment funds for msmes in low-income countries and almost a quarter of their investments in went to africa. official development assistance to msmes totaled more than us$ billion. section surveys the available evidence on msmes and job creation in africa. in reviewing the evidence we are confronted by an important limitation. representative employment data on micro enterprises and on informal enterprises of any size are virtually impossible to come by in africa. for this reason we cannot assess job creation and the quality of employment in micro and informal firms. there is an abundant literature, however, to suggest that many of our conclusions with respect to small formal firms hold a fortiori with respect to micro and informal enterprises. enterprise surveys show that about half of new jobs in africa are created in firms with - workers, but the data do the brookings institution and university of gothenburg, respectively. this paper is a revised version of page and söderbom ( ) written for the unu-wider project foreign aid research and communications – recom. the development orthodoxy that smaller firms are more efficient at job creation appears to be largely the product of pronouncements of the u.s. small business administration and by a range of us political leaders that out of new jobs in the usa are generated by firms with fewer than employees (birch, ). see for example world bank ( ). not tell anything about how long those jobs last. small firms everywhere have both higher birth and death rates than large firms. because the cross-country data cannot tell us anything about firm entry and exit, we turn to panel data from one african country, ethiopia. here we find a striking result: when we take into account the significantly lower survival rates of small firms, expected job growth for large and small firms is essentially the same. there are also substantial differences in the quality of jobs between small and large firms. small firms consistently trail large firms in wages paid and wage growth. section takes up these issues using data drawn from enterprise surveys of nine african countries. there is a strong positive relationship between wages and firm size. workers in small african firms are paid far less than employees in larger firms. in ethiopia we find a persistent difference in wages between large and small firms. although wages rise in all firms that survive, firms starting small do not close the wage gap with large firms. taken together the various strands of evidence suggest that it is time to rethink aid strategies for job creation based on support to small enterprises. section offers some preliminary suggestions on how this can be achieved. aid should target growing firms, and this argues in the first instance for policies and programs that reduce the constraints to the growth of firms, regardless of size. . small enterprises are big business financial and technical assistance to micro, small and medium enterprises is a major “product line” of the aid business. at the end of the global commitments of multilateral development banks (mdbs), bilateral donor agencies, and development finance institutions (dfis) to support msmes totaled around us$ . billion (siegesmund and glisovic ). official development assistance (oda) to msmes—the component of financing carrying at least a per cent grant element—exceeded us$ billion in . in some public and private investment funds committed more than us$ billion to smes in emerging markets through wholesale investment facilities. almost half of these investments went to sub-saharan africa ( per cent) and south asia ( per cent) combined. the international finance corporation is the largest dfi supporting smes. in , ifc committed us$ . billion to its sme finance portfolio. ifc financial intermediaries had an outstanding portfolio of . million sme loans that in addition there are a large number of non-governmental organizations (ngos) that deal with msmes. some of these are financed by official development assistance, but a growing number are funded wholly or partly by private philanthropy. while they are not the subject of this paper, which is focused on ‘aid and employment’, many of these organizations have similar rationales for their sme activities and the results apply equally. these estimates are approximate. there are data gaps in what donors and dfis self-report, and the information is not reported consistently across organizations. forty eight per cent of oda went to asia, per cent to the middle east and north africa, and per cent to sub-saharan africa (siegesmund and glisovic ). totaled us$ . billion in the same year (oecd ). in addition private philanthropies such as the citi foundation and for profit “social” investors are also active in msme finance. all the multilateral development banks have programs that address msme access to finance. some invest directly in enterprises through loans or equity; others provide loans to financial intermediaries—typically commercial banks—which in turn lend directly to enterprises. the majority of the multilateral banks also provide technical assistance (ta) to governments on a wide range of policy reforms that affect the business environment, such as business registration, licensing, labor regulations, contract enforcement, corporate taxation, and ease of exporting. bilateral donor strategies toward small enterprises vary greatly. some aid agencies finance msmes directly through equity or debt financing, while others provide wholesale finance through financial intermediaries. some donors provide advisory services to train banks in lending practices to smes and many also provide ta to small firms to prepare bankable proposals. at the firm level some donors provide technical assistance to improve business practices. value-chain programs where donors work with large corporations to connect them to small enterprises as suppliers or distributers have become increasingly popular. in addition, donors work directly with enterprises or through business and trade associations to help build supplier relationships and to help small businesses gain access to market information. aid agencies also focus on institutional, legal, and regulatory reforms intended to remove the constraints to growth faced by small businesses. . what do we know about small enterprises and job creation? despite the fact that much of the rationale for aid to small enterprises is centered on their role in creating jobs, we in fact know little about small enterprises and job creation in low-income countries, especially in africa. in part this is due to definitional problems. the definition of ‘small’ varies by country and by income level. richer economies like the member states of the oecd use cut-off points of fewer than workers to classify smes. in developing countries, where market size and average firm size are both much smaller, cut-off points of fewer than workers or workers are often used. in africa firms with more than workers employ about per cent of the labor force in the formal sector. medium-scale enterprises ( - workers) constitute the second leading employment category with about per cent of the labor force, and small firms (those with fewer than employees) employ a further per cent. for example, usaid’s development credit authority (dca) office typically looks for a local project that can assist smes to prepare bankable proposals in connection with a loan portfolio guarantee. there are also methodological problems that complicate attempts to draw conclusions from the evidence available on job creation by small firms. the most critical of these is the need to distinguish between gross and net job creation. small firms indisputably create new jobs, but they can also destroy jobs through higher failure rates. evidence from oecd countries and latin america indicates that small firms account disproportionately for firm turnover (haltiwanger, scarpetta, and schweiger ). assessing the impact of turnover on net job creation requires longitudinal (panel) firm-level data that record exit and entry. unfortunately, for developing countries in general, and for africa in particular, such data are very scarce. since small firms have higher exit rates, ignoring firm exit, will tend to exaggerate their role in creating new jobs. what do we know about smes and jobs in africa? ayyagari, demirgüç-kunt and maksimovic ( ) use world bank enterprise survey data to analyze the contribution of smes to total employment and job creation for developing economies. these data are limited in two important respects. first, because they are not panel (firm-year) data it is impossible to deal with the question of firm survival. while the authors’ acknowledge this shortcoming, they argue that the “churning” characteristic of the us and other mature economies is less present in developing countries. second, the data only cover registered firms with more than five employees. as we noted in the introduction, this excludes the vast majority of firms operating outside the formal sector. nevertheless, their research presents the most comprehensive picture available of the relationship between firm size, firm age and job creation in developing countries. the database compiled by ayyagari, demirgüç-kunt and maksimovic contains firm survey data from african countries. we were able to disaggregate the data and use it to describe regional patterns of employment and firm size. figure shows the distribution of total employment by firm size and region. we have chosen to present the data in four size categories: firms with - employees which we define as small enterprises in the african context, firms in the size ranges - and - employees which we define as medium-scale enterprises and firms with more than employees which we define as large. using these definitions, large firms are the largest employers in all six developing regions. [figure about here] for a discussion of some of the methodological problems associated with attempts to measure job creation by smes see haltiwanger et. al. ( ). see page and söderbom ( ) for a discussion of how researchers basing their research on recall data may come to conclude that small firms create more jobs than large firms when in fact the opposite is the case. to these they add data for another countries, mainly high-income economies drawn from other comparable sources. the definition of “large” varies in the literature, often depending on the income level of the country studied. we have chosen to follow the mainstream of the literature on firm size in africa and define large as a firm with or more workers. ayyagari, demirgüç-kunt and maksimovic ( ) present results using a definition of large based on firms employing more than workers. for africa in particular this increases the appearance that the majority of formal sector workers are employed in small and medium scale firms. in africa large firms employ about per cent of the formal sector labor force. medium-scale enterprises constitute the second leading employment category with about per cent of the labor force, and small firms employ a further per cent. this result emphasizes the critical role played by the definition of “small”. had we used a cut-off of employees for large enterprises, two-thirds of african jobs would have been found in “smes”. older firms are also where the jobs are. the largest proportion of african formal sector workers is found in firms more than years old (figure ). [figure about here] small firms in africa create a disproportionate share of new jobs in those economies in which formal sector employment is growing (figure ). in the median african country about per cent of new jobs were created in firms with - workers. this places africa squarely in the middle of the regional distribution of employment creation rates by small firms, leading europe and central asian and latin america and trailing east and south asia. [figure about here] in africa very young firms and older firms (more than years) have the highest rates of job creation (figure ). this is also true, although to a lesser extent, of east asia but is not characteristic of any other region. the finding that small, young firms are an important source of job creation in africa raises the concern that the cross-country data do not permit us to look at firm survival. is it possible that in africa—as in the united states and europe—small firms account for a disproportionate share of enterprise births and deaths and, therefore, a disproportionate share of both job creation and job destruction? [figure about here] tyler biggs made an early effort to answer this question using panel data from world bank enterprise surveys in five countries—ghana, kenya, tanzania, zambia and zimbabwe— covering a three year period in the early s. he reported that large firms (which he defined as larger than employees) were the dominant source of net job creation in manufacturing in four of the five countries. large firms contributed per cent of net job creation in ghana, per cent in kenya, per cent in zimbabwe, and per cent in tanzania. the data also showed higher rates of enterprise failure at the small end of the size distribution, and exit was an important factor in explaining the difference between gross and net job creation in small enterprises (biggs ). biggs results suggest that when the higher exit rates of small firms are taken into account, the assumption that small enterprises are net job creators in africa may not be valid. biggs results, however, are based on a small sample and very short time period of only three years. we would feel more confident if we were able to trace firm dynamics by size over a longer period. this of course excludes micro enterprises (of less than employees) and informal enterprises. job creation and destruction: evidence from ethiopia fortunately, we have detailed evidence on firm dynamics in one sector, manufacturing, and in one country, ethiopia. unlike most other african countries, ethiopia has collected a lot of data on performance and employment in the manufacturing sector. most of the existing data derive from surveys conducted by the central statistical agency (csa) of ethiopia. the most comprehensive dataset is that based on the large and medium manufacturing industries survey (lmms), which attempts to cover all manufacturing establishments in the country that engage ten persons or more and use power-driven machinery. page and söderbom ( ) use these detailed longitudinal data to analyze firm entry and exit and patterns of net employment growth across firms of differing size. they combine all lmms datasets from / to / . this yields nearly , firm-year observations. because most firms entered the market before the first survey year of / , in order to avoid selection bias they focus only on the subsample of new entrants over the period / - / . they find great diversity in the survival and growth outcomes of firms and persuasive evidence of “churning”. exit rates were significantly higher for small, young firms. half of the firms starting with employees (or fewer) were gone after years; and after years two thirds of the firms starting small had disappeared. however smaller firms that survived often grew. page and söderbom model firm survival and—conditional on survival—employment growth for the subset of new entrants, using a probit regression in which exit is the dependent variable, and initial size (employment at start-up) and years since start-up (age) are the key explanatory variables. among surviving firms smaller firms tended to grow employment faster than larger firms. but, in contrast to the results based on enterprise surveys, when the significantly lower survival rates of small firms are taken into account, expected job growth for large and small firms does not significantly differ. a job created today in a new small firm is more likely to disappear in - years than a job created in a new large firm, but because those small firms that survive create more jobs the number of new workers hired by small and large firms over the period will be about the same. . the quality of jobs: firm size, productivity and wages our focus on job creation to this point begs another important question: what is the quality of the jobs created? there is a large body of empirical evidence from developed and developing countries showing that large firms offer higher wages than small firms, even when differences in they also control for year effects. see page and söderbom ( ) for a fuller description of the model specification. worker education and experience and the nature of the industry are considered. in advanced countries, the wage differential between large and small firms for similar job categories is as much as per cent (brown, hamilton, and medoff ). in developing countries it can be as large as per cent (mazumdar ; rosenzweig ). large employers also offer better benefits in the form of pension plans, and life, health and accident insurance. large firms generally have better working conditions, especially in developing countries, and the jobs generated by large firms generally provide greater security than those generated by small firms (biggs ). if the objective of donors is not just to create any job, but also to create a good job—in terms of wages, employment duration and working conditions—the quality of jobs is important. of course, donors focused on poverty reduction may regard the quality of employment as secondary to the need to draw workers out of poverty through any job that offers a wage above the poverty threshold. as page and shimeles demonstrate in their contribution to this volume, aid has been largely unsuccessful in achieving that objective in africa as well, and we take the perspective that creating good jobs should be an important focus of aid policy, especially for the young. we draw on data from two sources to address the question: how good are the jobs created by small firms? first, we use world bank enterprise survey data to study how simple measures of firm performance and wages differ across firms of differing size for a number of countries in africa. we then turn to the ethiopia panel data to gain a deeper understanding of wage dynamics. firm size, productivity and wages in africa we have assembled data on the following nine african countries from the world bank enterprise surveys: ethiopia ( ; firms); ghana ( ; firms); kenya ( ; firms); mozambique ( ; firms); nigeria ( ; , firms); rwanda ( ; firms); senegal ( ; firms); tanzania ( ; firms); and uganda ( ; firms). the size range of firms is wide. the smallest firm in our dataset employs two people while the largest firm has , employees. the median employment is , the sample average is . , and the coefficient of variation is . . sixty-one per cent of the firms in the pooled sample belong to the smallest size group of less than employees, per cent employ between and workers; only per cent of the firms have - workers and per cent of the firms have more than workers. next, we compute differences in simple measures of productivity and wages for firms of differing size. using the pooled dataset, we begin by regressing the logarithm of value-added per worker on a third-degree polynomial in log employment plus a full set of country dummies. based on this regression we plot predicted value-added per worker normalized by predicted see for example teal ( ). unfortunately we do not have data on the number of hours worked per individual. if, as seems likely, hours worked per individual tends to be positively correlated with firm size, the strong relationship between wage and size documented in figure may partly be driven by differences in working hours across small and large firms. value-added per worker for a firm with employees. the result is shown in figure . there is a strong positive relationship between value-added per employee and firm size. the size- productivity differential is very pronounced, even among relatively small firms. firms with employees have, on average, twice as much value-added per worker as firms with employees. value-added per worker in african firms with employees is more than three times higher than that in firms with employees, and in firms with employees it is . times higher. in other words, the average worker in a -worker firm produces as much value-added in minutes as the average worker in a -worker enterprise does in an hour. [figure about here] differences in productivity are reflected in differences in wages. figure shows how the average wage paid to workers varies with firm size. workers in small african firms are paid far less than employees in larger firms. the earnings of the average worker in a -worker firm are about per cent higher than the earnings of someone working in a -worker enterprise. a significant portion of the size-wage gap is attributable to differences in skills: large firms tend to hire better educated and more experienced workers than small firms. however, conditional on skills, there still remains a large, statistically significant wage difference across small and large firms (oi and idson ; söderbom et al. ). teal ( ) provides evidence that the quality of employment differs dramatically between small and large firms in ghana and tanzania. in both economies workers with similar observable characteristics in terms of age, education and tenure of employment earn substantially higher wages as firm size increases. [figure about here] wage dynamics and firm size: evidence from ethiopia our analysis of the african nine-country dataset showed that large firms pay higher wages than small firms. the ethiopia data offer some deeper insights into the relationship between firm size and wages. using the entire pooled lmms data set page and söderbom ( ) find a strong statistically significant relationship between the average wage in the firm and firm size (measured as log employment). on average a per cent increase in firm size is associated with a . per cent higher wage. given that the range of firm sizes is large this predicts very sizable differences in wages between large and small firms. when they restrict their sample to new entrants only, page and söderbom find an almost identically large size-wage gap for new entrants in the year of entry. in ethiopia new small firms pay much lower wages than new large firms from day one. an important question is whether the small firms that survive (and typically grow) catch up with large firms with respect to wages. the answer in ethiopia is no. there is no statistical evidence an important reason why small african firms have much lower labour productivity than large african firms is that capital intensity varies strongly with firm size. that, conditional on survival, wage growth rates are higher among small entrants than among large ones. the size-wage gap established at the year of entry persists. firms starting small do not close the wage gap, even if they survive and grow. implications for aid we can now put the dimensions of firm dynamics—growth and survival—together with our evidence on productivity and wages, to say something about the overall potential of small and large firms to create and sustain jobs and high wages. the bottom line is this: • jobs in small firms tend to disappear at a high rate because of high failure rates, but if small firms survive they grow employment faster than larger firms. these two effects roughly balance each other out, so that the expected job growth across small and large firms is about the same. • large firms offer the prospect of much more secure employment because they have much higher survival rates. • and, in terms of wages there is a big, big difference. small firms create low-wage jobs and the evidence suggests that wages in small firms do not catch up to those in large firms, even if they grow. what are the implications for aid policy? while—depending on the size cut-off used—small enterprises may be “where most of the jobs are” in africa, our evidence indicates that once firm survival is taken into account, small firms and large firms generate essentially the same numbers of net new jobs over the medium term. at least in ethiopia, the romantic notion that small enterprises are a powerful engine of job creation is not supported by the evidence. our evidence is consistent with what we know about small enterprises and job creation in other economies (haltiwanger, scarpetta, and schweiger ). moreover, the jobs that small firms create are less attractive than those in larger enterprises. small firms across africa have higher job turnover and persistently lower wages than larger firms. in sum, small firms are the wrong target for aid programs aimed at creating good jobs, the sorts of jobs that andrew mitchell and the european commissioners were referring to in their remarks quoted in the introduction. aid needs to target those firms that are successful at creating “better jobs”. size alone cannot predict which firms will grow. indeed, we know that a small firm is more likely to die than a larger firm, despite the fact that if the small firm survives it will grow faster. this argues in the first instance for policies and programs that reduce the constraints to the growth of all firms, regardless of size. beyond interventions that reduce the constraints to enterprise growth, donors can experiment with programs that identify and support growing firms and that help to increase firms’ chances of survival. below we offer one concrete suggestion in each of these three areas. reducing the constraints to enterprise growth aid can reduce the constraints to enterprise growth by supporting public actions to improve the “investment climate”—the regulatory, institutional and physical environment within which firms operate. investment climate reforms are a traditional “product” of the aid industry in africa. around one quarter of official development assistance, some us$ billion per year, currently supports investment climate improvements (page ). however, the way in which the international community has chosen to define priorities for the reform of the investment climate needs to be changed. the donor agenda for the investment climate has largely centered on easily measured reforms to trade, regulatory, and labor market policies. this “made in washington” approach to investment climate reform has largely failed to boost private investment and enterprise growth in africa (page ). donors can reshape the investment climate agenda to make it more effective in removing the obstacles to enterprise growth. the enterprise surveys organized by the world bank have generated some data on the perceived obstacles to investment and growth by firms in africa. the constraints faced by firms are somewhat different depending on firm size, but the differences are perhaps less striking than one might expect (figure ). firms of all sizes highlight infrastructure deficiencies—power, transportation and telecommunications—as significant barriers to enterprise growth. africa lags at least percentage points behind the average for low-income countries on almost all major infrastructure measures. in addition the quality of service is low, supplies are unreliable, and disruptions are frequent and unpredictable. african firms report losing per cent of their sales because of frequent power outages—a figure that rises to per cent for firms unable to afford backup generation (world bank ). [figure about here] closing africa’s infrastructure gap will require around us$ billion a year, about per cent of the region’s gdp. forty per cent of the total spending needs are for power, alone. until quite recently africa’s traditional development partners have shown little willingness to finance infrastructure. despite the magnitude of the infrastructure gap, infrastructure financing by the members of the oecd development assistance committee (dac) has been falling as a share of oda since the early s (page ). while it is clearly unrealistic in the current fiscal environment in the oecd to count on aid to fill the infrastructure financing gap, new approaches there is by now a large literature on the costs of doing business in africa. see for example the annual africa competitiveness report of the afdb, world economic forum and the world bank. and products such as guarantee instruments could leverage limited donor financing by reducing the perceived risk of private debt financing for infrastructure. identifying and supporting survivors most firms start small and those that survive create jobs at a faster rate than large firms. one novel way for aid to support job creation and growth in africa is to experiment more boldly with interventions designed to identify new small firms with the potential for growth. rather than providing targeted support (such as training or subsidized loans) to small firms at start-up, donors might consider, for example, giving a small grant to new firms below a certain size. the grant, which would not be conditional on a credit appraisal, is intended to provide working capital for the startup phase of the firm. the implementing agency would refrain from further interventions designed to improve the “creditworthiness” or profitability of the enterprise and observe over a period of, say, - years which firms have been able to survive. governments and donors would then use information gathered from the surviving firms to provide them with support tailored to their needs. at that point the bottleneck to growth might not be finance (after all, the firms have by now had some time to accumulate own savings); perhaps inadequate skills or lack of marketing and distribution channels will matter more. such interventions are amenable to randomized experiments, and it should, therefore, be possible to conduct rigorous impact evaluations of the programs. building firm capabilities as we noted above, for surviving firms the critical bottleneck to growth may turn out not to be finance, but in the jargon of modern microeconomics lack of “firm capabilities”. in most industries productivity and quality are determined by a set of interlocking elements of know- how, tacit knowledge or working practices possessed by the individuals who comprise the firm’s workforce—both managers and workers (sutton ). aid agencies can support the acquisition and dissemination of firm capabilities by supporting government efforts to attract foreign direct investment (fdi) and through management training. because firm capabilities are not codified, both the initial introduction of new capabilities and their eventual transfer to other firms depend primarily on learning through firm to firm interactions. foreign direct investment (fdi) is one means of introducing high capability firms into a lower capability environment, and policies and institutions for attracting fdi are therefore a key tool in capability building. surprisingly, africa’s foreign investment promotion agencies have not been highly successful in promoting fdi outside of the natural resources sector. donors should prioritize supporting the development of effective foreign investment promotion agencies at the country level. “value chain” programs designed to connect foreign investors with domestic firms could also be strengthened. managerial human capital and management practices play a key role in firm performance (bloom et al. ; syverson ). case studies of the development of manufacturing firms in asia and africa consistently show that better management leads to improvements in productivity and profitability. better managed firms also have higher survival rates. randomized experiments in africa and latin america have found that the majority of business owners—especially among small firms—have inadequate knowledge of basic management and that rudimentary management training can improve business practices (bloom et al. ; sonobe, suzuki and otsuka ). these results suggest that programs of management and technical training for firms that have shown an ability to survive the start-up phase have a potentially large payoff. to realize the promise of management training, however, donors will need to be prepared to abandon existing programs, introduce new approaches and rigorously evaluate the results. a recent critical review of donor-sponsored business training programs for micro and small firms found that the impacts of such programs on performance, survival and employment growth were small in virtually all cases and in most cases not statistically significant (mckenzie and woodruff ). . conclusions the events of the arab spring have put job creation on the front burner of development assistance. an attractive characteristic of small enterprise programs for donors is that they appear to link jobs and aid. based on cross-country data, donors have assumed that small enterprises are ‘where the jobs are’ and that by growing this size class of firms, net employment can be increased rapidly. but, we find no persuasive evidence of a difference between small and large firms in their ability to generate net new jobs in africa. the conclusion that small firms are “job creators” rests on the assumption that exit by small enterprises is not an important factor in net job growth. panel data cast serious doubt on this assumption. in the one african country for which we have comprehensive data on the life-cycle of firms, ethiopia, the more rapid growth of small firms is offset by a very high rate of firm failures. net job creation by small firms and large firms is essentially the same in the medium term. moreover, large firms have substantially higher levels of productivity and pay much higher wages than small firms. what do our results mean for aid? first and foremost, that it is time to stop overselling small enterprise development as the panacea for employment creation. while it is popular to extoll the virtues of small businesses both in high-income and developing countries, their supposed preeminence as “job creators” is not supported by the evidence in either setting. moreover, if the objective is to create “good” jobs, and not just any job, a much more nuanced approach to aid and employment will be needed. more broadly, our results provide a caution against targeting programs of support to firms on the basis of ex ante criteria, no matter how appealing and apparently grounded in “fact”. a more productive approach to aid and employment would be to support the more rapid growth of firms of any size. one traditional “product line” of the aid industry—reform of the investment climate—can be redesigned and expanded to support the growth of firms. a better environment would benefit all firms in africa, large and small. moving beyond the investment climate, operations aimed at identifying and providing bespoke support to surviving firms and programs to increase firm capabilities offer new better prospects of helping africa create good jobs. references ayyagari, m., a. demirgüç-kunt, and v. maksimovic ( ). ‘small vs. young firms across the world’. policy research working paper , washington, dc: world bank. barry, f. 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( ). ‘aid, the private sector and structural transformation in africa’. unu-wider working paper, / . helsinki: unu-wider. page, j. and m. söderbom ( ). ‘is small beautiful? small enterprise, aid and employment in africa’. unu-wider working paper, / . helsinki: unu-wider. page, j. and m. söderbom ( ) ‘are small firms job creators in low income countries? evidence from ethiopia’ washington, dc: the brookings institution rosenzweig, m.r. 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( ). ‘higher education and economic development in africa: a review of channels and interactions’. csae wps/ - , centre for the study of african economies, university of oxford. world bank ( ). transforming africa’s infrastructure. washington, dc: world bank. world bank ( ) world development report : jobs washington, dc: world bank figure : employment share by firm size class source: based on ayyagari et al. ( ); authors’ calculations. figure : employment share by firm age source: based on ayyagari et al. ( ); authors’ calculations. afr eap eca lac mna sar < - - + afr eap eca lac mna sar ≤ years - years - years + years figure : job creation as a share of total job creation by firm size class source: based on ayyagari et al. ( ); authors’ calculations. figure : job creation as a share of total job creation by firm age source: based on ayyagari et al. ( ); authors’ calculations. - - - afr eap eca lac sar < - - + - - - - afr eap eca lac sar ≤ years - years - years - years figure : value-added per worker and firm size in nine african countries note: the graph shows predicted value added per worker based on a regression of log value added per worker on a third-order polynomial in log employment and country dummies. the predictions are normalized at for a firm with five employees. source: authors’ calculations based on firm-level data from ethiopia (year ), ghana ( ), kenya ( ), mozambique ( ), nigeria ( ), rwanda ( ), senegal ( ), tanzania ( ), and uganda ( ), collected as part of the world bank’s enterprise surveys (www.enterprisesurveys.org). a fri ca employment http://www.enterprisesurveys.org/ figure : average wages and firm size in nine african countries note: the graph shows predicted average wage based on a regression of log labor cost per worker on a third-order polynomial in log employment and country dummies. the predictions are normalized at for a firm with five employees. source: authors’ calculations based on firm-level data from ethiopia (year ), ghana ( ), kenya ( ), mozambique ( ), nigeria ( ), rwanda ( ), senegal ( ), tanzania ( ), and uganda ( ), collected as part of the world bank’s enterprise surveys (www.enterprisesurveys.org). a fri ca employment http://www.enterprisesurveys.org/ figure : perceived obstacles to the operation of small and large firms * including inputs and supplies. note: firms are classified as large if they employ or more workers; otherwise small. source: authors’ calculations based on firm-level data from ethiopia (year ), ghana ( ), kenya ( ), mozambique ( ), nigeria ( ), rwanda ( ), senegal ( ), tanzania ( ), and uganda ( ), collected as part of the world bank’s enterprise surveys (www.enterprisesurveys.org). . . . labour regulations political instability courts inadequately educated workforce telecommunications business licensing & permits customs & trade regulations access to land crime, theft & disorder corruption tax administrations informal sector competitors transportation of goods* access to finance tax rates electricity large firms small firms http://www.enterprisesurveys.org/ abstract . introduction . small enterprises are big business . what do we know about small enterprises and job creation? . the quality of jobs: firm size, productivity and wages implications for aid . conclusions references mckenzie, d. and c. woodruff ( ) “what are we learning from business training and entrepreneurship evaluations around the developing world?”, policy research working paper washington, dc: world bank. sex-related similarities and differences in the neural correlates of beauty camilo j. cela-condea, , francisco j. ayalab, , enric munara, fernando maestúc, marcos nadala, miguel a. capóa, david del ríoc, juan j. lópez-ibord, tomás ortizc, claudio mirassoe, and gisèle martya alaboratory of human systematics, universidad de las islas baleares, palma de mallorca, spain; bdepartment of ecology and evolutionary biology, university of california, irvine, ca ; ccentro de magnetoencefalografía dr. pérez modrego, universidad complutense, madrid, spain; dinstitute of psychiatry and mental health, san carlos clinical hospital, universidad complutense, madrid, spain; and einstituto de física interdisciplinar y sistemas complejos, consejo superior de investigaciones científicas (csic), palma de mallorca, spain contributed by francisco j. ayala, january , (sent for review january , ) the capacity to appreciate beauty is one of our species’ most remarkable traits. although knowledge about its neural correlates is growing, little is known about any gender-related differences. we have explored possible differences between men and women’s neural correlates of aesthetic preference. we have used magne- toencephalography to record the brain activity of male and female participants while they decided whether or not they con- sidered examples of artistic and natural visual stimuli to be beau- tiful. our results reveal significantly different activity between the sexes in parietal regions when participants judged the stimuli as beautiful. activity in this region was bilateral in women, whereas it was lateralized to the right hemisphere in men. it is known that the dorsal visual processing stream, which encompasses the supe- rior parietal areas, has been significantly modified throughout human evolution. we posit that the observed gender-related differences are the result of evolutionary processes that occurred after the splitting of the human and chimpanzee lineages. in view of previous results on gender differences with respect to the neural correlates of coordinate and categorical spatial strategies, we infer that the different strategies used by men and women in assessing aesthetic preference may reflect differences in the strategies as- sociated with the division of labor between our male and female hunter-gatherer hominin ancestors. aesthetic preference � brain lateralization � gender differences � human evolution � magnetoencefalography neuroimaging studies have elucidated a basic picture of theneural correlates of the appreciation of beauty. activity has been reported during aesthetic preference tasks in a network of brain regions, including the frontal pole, orbitofrontal cortex, left dorsolateral prefrontal cortex, caudate nucleus, temporal poles, anterior cingulate cortex, and occipital cortex ( – ). behavioral experiments have shown that men and women rate the beauty of visual artistic and decorative stimuli in different ways ( , ), but the extent to which the neural correlates of decisions about aesthetic beauty are inf luenced by the gender of the participants, is currently unknown. gender differences in brain activity related with cognitive ( – ) and affective ( , ) processes have been reported in many instances, showing in many cases differences in lateralization pat- tern. such tasks as word generation, spatial attention, and working memory, are lateralized differently in women and men, although not all studies are consistent ( ). the present study seeks to identify differences and similarities in brain activity between male and female participants while rating the beauty of artistic and non-artistic visual stimuli, by means of magnetoencephalography (meg)—a technique that detects changes in the magnetic fields generated by the postsynaptic activity of neurons, with a temporal resolution of milliseconds. we also seek to ascertain whether any possible differences between the sexes are due to evolutionary processes that occurred along the evolution of the human lineage or in an earlier primate ancestor. if gender- related differences are identified in relatively conserved brain regions, it is possible that they were inherited from our primate ancestors. if, conversely, differences between men and women appear in brain regions known to have undergone considerable modifications after the human and chimpanzee lineages split, it is likely that they are due to evolutionary processes that were espe- cially relevant to the hominin way of life. most gender differences identified in our study correspond to parietal regions. in the genus homo, parietal development leading to brain globularity has been described by palaeoneurologists as a ‘‘modern pattern,’’ characteristic of homo sapiens. in contrast, allometric vertical development, frontal enlargement, and parietal relative shortening would be characteristic of an archaic structural trajectory shared by non-modern taxa, specially homo erectus and homo neanderthalensis ( , ). results summary. meg data were recorded while participants viewed images of unfamiliar paintings by artists from different artistic schools, and ‘‘natural’’ photographs depicting diverse objects and landscapes, urban and rural (fig. ). participants were asked to indicate whether they found each image beautiful or not, empha- sizing the importance of expressing their own impressions. the results (table and fig. ) show that within particular time frames certain brain regions exhibited different activity for stimuli rated as beautiful than for stimuli rated as not beautiful. during the initial ms there were no differences in brain activity associated with stimuli rated beautiful rather than not beautiful, in either women or men. brain activations in the different time windows are depicted in fig. and detailed in table . during the - to -ms interval, activity was greater in parietal regions for stimuli rated as beautiful than for those rated as not beautiful. moreover, whereas in women this activity was found in both hemispheres, in men it was mainly located in the right hemisphere. our analysis also revealed small foci of activity in left hemisphery areas that have been shown to be involved in somatosensory (ba , ) ( ) and, slightly, in motor (ba , ; see table ) ( ) tasks. with regards to the main effects of aesthetic preference, our results show that there is no differential brain activity associated with stimuli rated as beautiful and not beautiful before milli- seconds after stimulus onset. between and ms clear differences in activity appear in a large region of the left superior parietal cortex, and a small region of the left inferior parietal cortex, in the supramarginal gyrus. these regions show activity differences (beautiful more activity than not beautiful) until � ms. after ms the differences extend to superior and inferior right parietal author contributions: c.j.c.-c., e.m., f.m., m.n., m.a.c., t.o., and g.m. designed research; c.j.c.-c., e.m., f.m., m.n., m.a.c., d.d.r., and g.m. performed research; j.j.l.-i., t.o., c.m., and g.m. contributed new reagents/analytic tools; c.j.c.-c., f.j.a., e.m., f.m., m.n., m.a.c., d.d.r., t.o., and g.m. analyzed data; and c.j.c.-c., f.j.a., e.m., f.m., m.n., and g.m. wrote the paper. the authors declare no conflict of interest. to whom correspondence may be addressed. e-mail: cjcela@atlas.com.es or fjayala@uci.edu. www.pnas.org�cgi�doi� . �pnas. pnas � march , � vol. � no. � – p sy c h o lo g y ev o lu ti o n d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , regions. fig. shows the areas that were more activated in beautiful than in not-beautiful perception, regardless of the participant’s gender (that is, the main effects of aesthetic preference). activity in motor and somatosensory areas. the differences detected in motor and somatosensory areas might be attributed to brain processes related with the physical activity of the response, because participants were asked to lift a finger to signal their response. however, the experiment counterbalanced the response mode, such that half of the participants lifted their finger to indicate they thought the stimulus they were seeing was beautiful, whereas the other half did so to show they thought it was not beautiful. activity in premotor and motor cortex has been shown in other contexts to be related with tasks involving spatial cognition ( ) and mental rotation ( ). in our experiment, the sensation of beauty associated with visual stimuli might involve heightened spatial cognitive processes, in- creased somatosensory perception, and the planning and execution of movements. viewers would ‘‘navigate,’’ so to speak, through the space offered by the beautiful image, in agreement with a view recently argued by freedberg and gallese ( ). kawabata and zeki ( ) found greater activity in the motor cortex when participants viewed images they considered to be ugly. calvo-merino et al. ( ) found that beauty ratings of filmed dance movements were related with the right premotor cortex (activity was greater for beautiful stimuli). these authors proposed that the motor system is involved in aesthetic preference at different levels: (i) basic processing and withdrawal behaviors, and (ii) a ‘‘form of motor resonance,’’ as part of activity in a broader network of regions integrating the ‘‘mirror system.’’ however, earlier studies found activity in the prefrontal cortex while participants performed aesthetic preference tasks (see ref. for a review). differences between the results found in ref. and this article can be attributed to the source reconstruction model used. the single dipole ap- proach (used by ) models dipole for every point in time. however, the minimum norm estimation (mne) procedure used in the present article assesses the possible contribution of dipoles at each point in time, taking into account the possibility of distributed sources. another important difference is the threshold for selecting the dipoles. cela-conde et al. ( ) used a gof (goodness of fit) and correlation � . . this threshold tends to overestimate part of the activity, such that it is possible that other activity, taken into account with the mne, is overlooked by the single dipole method. in the present article we chose mne instead of the single dipole, because we assume that the aesthetic decision process can be distributed in different brain regions rather than being localized in a particular one. the mne takes this possibility into account, but the single dipole does not. angular gyrus. the most relevant results involve activity in the angular gyrus (ag), which is greater for stimuli rated as beautiful in both sexes, and is sustained for a relatively long time interval ( – ms for both men and women, and again – ms for men and – ms for women). ag activity has been associated with the processing of categorical and coordinate spatial relations ( ) and during saccadic eye movements ( ), and thus ag activity is not surprising while viewing objects. however, this does not explain why there are statistically significant differences between beautiful and not-beautiful stimuli. the observation of ag activity during non-canonical as opposed to canonical viewing of objects ( ) is helpful in the interpretation of our results. unusual orien- tations can be described as non-canonical—a cone standing on its point and not on its base, for instance. thus, it seems that unusual presentation of objects is related to key aspects of the appreciation of beauty, a view that has been asserted by a number of investigators ( – ). seashore and metfessel ( ) pointed out many years ago fig. . two examples of the stimuli used in the experiment. (left) ‘‘paisaje de capri’’ ( ), painting by francisco pradilla y ortiz, printed with permission from the museo nacional del prado (madrid, spain) archivo fotográfico. (right) photograph of an urban landscape. table . brain areas in which activity is significantly greater for stimuli rated as beautiful rather than not beautiful subject gender time interval – – – – – – female left superior parietal (ba ) medial postcentral and left superior parietal (ba – ) right angular gyrus (ba ) left inferior parietal (ba ) no differences right angular gyrus (ba ) male right postcentral (ba ) right postcentral (ba ) and right inferior parietal (ba ) right angular gyrus (ba ) right superior parietal (ba ) with an extension towards the angular gyrus (ba ) right angular gyrus (ba ) and right precentral-postcentral (ba – ) left precentral- postcentral (ba – ) all reported differences are statistically significant (p � . ). areas correspond to those used by tzourio-mazoyer et al. ( ). in parentheses: ba, brodmann area, following brodmann’s nomenclature. � www.pnas.org�cgi�doi� . �pnas. cela-conde et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , that, in music, deviation from the regular constitutes an art prin- ciple. similarly, fauvism, which depicts unusually colored objects, has been associated with distinctive neural correlates of visual perception ( ). accordingly, our results may imply that unex- pected depictions of familiar objects and, in general, ambiguity ( ), which require spatial abilities of rotation and transformation, are a primary component of aesthetic preference in both sexes. differences between the sexes: categorical vs. coordinate spatial strategies. our results showing an early activity of parietal areas for stimuli rated as beautiful in both sexes seem to indicate that the processing of spatial relations is crucial in the human appreciation of beauty. however, as our results clearly show, activity in the parietal regions is bilateral in the case of women but lateralized to the right hemisphere in the case of men. this is not atypical for many kinds of activity; many studies have found that male visual structures and processes tend to be hemispherically asymmetrical, but they tend to be more symmetrical for women ( ). the lateralization differences between men and women identified in the present experiment can be explained by kosslyn’s ( ) notion of separate processes that code and represent different kinds of spatial relations among objects. categorical spatial relations refer to positions of objects or their parts in broad categories of location regarding other elements, such as ‘‘above or below,’’ ‘‘left or right,’’ ‘‘in front or behind,’’ ‘‘inside or outside.’’ these categorical spatial relations play a role in tasks that do not require a precise location. conversely, coordinate spatial relations involve more precise met- rical information about distances among objects. hugdahl et al. ( ) have noted that in a mental rotation task men tend to use coordinate spatial relations, whereas women tend to process spatial relations in a categorical fashion. these strategies are associated with activity in different hemispheres. the left hemisphere seems to be more involved in the exploration of categorical spatial relations, whereas processes in the right hemisphere seem to underlie coordinate spatial relations ( , , ). hence, it appears that women and men engage different strategies of spatial analysis during aesthetic preference activity. strongly lateralized activity in the right hemisphere suggests that men use coordinate-based strategies. conversely, activity in both hemispheres, although mainly and longer in the left hemisphere, suggests women rely on categorical strategies more than men do. discussion numerous cladistic episodes have given rise to different lineages throughout human evolution. at least cladistic events are gener- ally recognized: (i) separation between the human and chimpanzee lineages; (ii) appearance of the genus homo and its divergence from the paranthropines (robust hominins); and (iii) emergence of the species homo sapiens, whose likely sister group was homo nean- derthalensis ( ). it is possible to identify anatomical apomor- phies—i.e., distinctive derived traits—that distinguish each of those lineages and that are used to identify each taxon. however, the significance of derived traits is more than taxonomical. the adap- tive success of the taxon after a phylogenetic event is usually grounded precisely on its apomorphies. examining the sets of primitive and derived traits of a new lineage may suggest hypotheses concerning the selective processes that shaped the lineage. behavioral traits may also be considered apomorphies, at least in the broad sense. indeed, distinctive behaviors often are greatly significant to account for a lineage’s adaptive strategies. thus, it is common to refer to bipedalism as a distinctive feature of the tribe hominini, the manufacture of increasingly sophisticated tools as distinctive of the genus homo, and symbolism as distinctive of h. sapiens. symbolism, in this context, includes such phenomena as fig. . brain areas in which activity is significantly greater (p � . ) for stimuli rated as beautiful rather than not beautiful by women and men during different time intervals. the time window between and ms showed left superior (spl) and inferior parietal lobe (ipl) in women and right inferior motor area (ima) in men. the time window – ms showed bilaterally spl and ipl in women and right spl and ima in men. a – -ms time window showed right ipl in women and right spl and ipl in men. the time window - to ms showed left and right ipl in women and right spl and ipl in men. in the time window between and ms, differences were concentrated on the right ipl in women and right motor area in men. fig. . brain areas in which activity is significantly greater (p � . ) for stimuli rated as beautiful rather than not beautiful by all participants during different time intervals. the time window – ms showed superior parietal lobe (spl) bilaterally and left inferior parietal lobe (ipl). the time window – ms again showed spl and ipl bilaterally and in addition right inferior motor area (ima). the time window – ms showed right spl and right ipl. the time window – ms showed right spl, ipl bilaterally and left mid frontal gyrus. the time window – ms showed right ipl and – -ms right ipl. cela-conde et al. pnas � march , � vol. � no. � p sy c h o lo g y ev o lu ti o n d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , language, and the production of objects that are considered beau- tiful but may not have obvious practical use. particular lineages are associated with distinctive apomorphies, but large taxons may consist of several lineages, which are in turn differentiated by distinctive traits. thus, within the genus homo and even within a single ‘‘species’’ such as homo erectus s.l., there is considerable variation in anatomical features, which, in the opinion of at least some authors, justify the identification of several species among the middle pleistocene hominins ( ). one feature that varies among taxa is the degree of gender dimorphism, which has inspired models of human evolution that assume different adaptive strategies in males and females ( ). here, we raise the question whether differences may also have evolved in the human lineage concerning appreciation of the beauty of objects, symbols, and art. if such sex-related differences have evolved, the issue arises, how could they be detected? the use of symbols and the capacity to appreciate the beauty of objects and to create them is generally accepted as a significant event in the evolution of h. sapiens. indeed, the capacity to produce and to appreciate aesthetic objects is frequently regarded as an important step in the evolution of the human mind, although when this capacity first appeared is a matter of contention ( ). social behavior, language, a variety of mental capacities and neurological functions, and even diseases, such as schizophrenia, have been related with the appearance of the capacities to appreciate beauty and to produce beautiful objects. making beautiful objects may indeed be an indication of a capacity to appreciate beauty ( , ). together with social organization, the cognitive capacity expressed by the use of symbolism may have decisively contributed to the demographic expansion and geographic dispersion of h. sapiens ( ). the importance of aesthetic appreciation in human evolution is evident. the value of object decoration—including the decoration of the body itself—for expressing social behaviors in all cultures has been noticed by anthropologists, ethologists, and psychologists ( ). the most obvious explanation for the perception of beautiful features in objects, and for the tendency to decorate the human body, is sexual selection. selective processes related with gender have granted different primate species the visual perception of color, particularly in the body of opposite-sex conspecifics ( ). it is reasonable to hypothesize that the human species, capable of altering its own appearance through decorative colors and draw- ings, must have evolved the capacity to appreciate beauty. the production and appreciation of colors and symbolic representation may, thus, have first evolved in association with sexual selection. once these traits appeared they could be used for a variety of purposes in social life. when did the capacity to appreciate beauty evolve? the evolu- tionary changes associated with the necessary cognitive develop- ment for appreciating the beauty of objects is often linked to the appearance of symbolism ( ). however, there is no universal agreement as to what counts as evidence for symbolism and symbolic behavior. alternative proposals include the manufacture of any symmetric object without any apparent practical use ( – ), or of explicitly decorative ornaments, or of the pigments used to paint them ( , ) for some authors, the construction of objects resembling a human body would be sufficient evidence of symbol- ism ( ), whereas others assert that only realistic paintings or sculptures, i.e., works of art, can be considered as true manifesta- tions of a symbolic capacity. the arguments in favor of the various and often contradictory points of view have been reviewed by appenzeller ( ). in any case, the production of decorative and artistic objects is widely considered as a fundamental stage in the emergence of modern human behavior. but, the study of the human brain processes related with the cognitive activity of appreciating beauty or art is still in its infancy. a valuable clue to trace the evolutionary roots of the gender- related differences that we have identified underlying aesthetic preference is to assess whether the differences involve a brain region exhibiting primitive or derived traits. when compared with monkeys and apes, the human parietal cortex exhibits a number of derived aspects. hence, the parietal differences between men and women would have occurred after the first cladistic event men- tioned above—i.e., the separation of chimpanzee and human lineages—and probably impacted spatial cognition. humans differ from other primates in certain features related with the cortical representation of the magnocellular visual pathway, linked to the analysis of motion, perspective, relative size of objects, and depth ( ). the human brain area v a (a secondary visual area) is sensitive to motion cues and uses them to extract -dimensional information, whereas the monkey area v a does not share this function ( ). orban et al. ( ), using comparative fmri (a technique for measuring brain activity that detects the changes in blood oxygenation linked to neural activity) data and computerized brain warping, have suggested that the ventral and dorsal visual streams have not evolved equally along the human lineage. rather, the areas included in the ventral stream, related with object representation and categorization, have undergone a smaller ex- pansion than those of the dorsal stream, which are involved in the representation of space and the analysis of visual information to organize action. the parietal areas of the dorsal stream receive only information from the magnocellular system, which support the aforementioned idea of an enhancement of the magnocellular cortical representations during human evolution ( ). if it is accepted, as we suggest, that the parietal regions in humans, when compared with other primates, are derived (apo- morphic), the question arises whether it is possible to identify the cladistic event within the hominin lineage that accounts for this evolutionary modification. obviously, we cannot use the same comparative methods that are used when comparing humans with living primates. nevertheless, investigations of the endocranial morphology of different taxa of the genus homo have provided some insight ( ). according to bruner et al. ( ), the brain of modern humans evolved after a parietal development that ‘‘may have represented a key to surpass the encephalization constraints imposed by the archaic structural model.’’ the differences between the decorative objects found in neandertal and modern human sites support that idea of a ‘‘modern brain’’ capable of appreciating beauty and its uses in different ways ( ). our results suggest that parietal regions of the brain of modern humans, which exhibit clearly derived traits, have a crucial role in the visual appreciation of beauty. if the dorsal visual pathway has been subjected to evolutionary pressures that have led to the aforementioned modifications during human evolution, we can confidently assume that sex-related differences in this pathway appeared after the human and chim- panzee lineages split. it can also be assumed that some gender- related differences are related to events of significant importance throughout human evolution. we have identified differences be- tween men and women in brain processes involved in aesthetic preference. how could the evolution of these differences be inter- preted in phylogenetic terms? silverman’s and eals’s ( ) ‘‘hunter- gatherer hypothesis’’ (hg-h) of gender differences in spatial abilities provides the most convincing scenario. they argue that the differences in spatial ability between men and women were asso- ciated with the division of labor between the sexes in hunting and gathering. tracking animals and foraging for plant food involve different spatial scenarios and, hence, require different kinds of spatial skills. silverman and eals ( ) suggest that abilities involved in hunting include the orientation in relation to objects and locations that may be in or out of view, and thus require cognitive transformations that allow keeping an accurate orientation while moving. conversely, foraging requires recognizing and remember- ing the contents of varied object assemblies and the spatial relations between objects. the hunter-gatherer hypothesis does not regard gender differ- ences in the performance of spatial tasks as the product of different � www.pnas.org�cgi�doi� . �pnas. cela-conde et al. d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , levels of a single ability, but as the result of the use of different spatial strategies that involve different abilities. women tend to be more aware than men of objects around them, including those that seem irrelevant to the current task ( ), whereas men out-perform women in navigation tasks ( ). men tend to solve navigation tasks by using orientation-based strategies involving distance concepts and cardinal directions, whereas women tend to base their activities on remembering the location of landmarks and relative directions, such as ‘‘left from,’’ or ‘‘to the right of’’ ( ). it could be argued, against this scenario, that differences between women and men regarding spatial strategies are the result of the particular conditions and gender roles that have become estab- lished in developed societies. however, an experimental study involving extant ethnic groups, has provided support to the hunter-gatherer hypothesis of human spatial gender differences ( ). in all hunter-gatherer groups, men scored significantly higher than women did in a test of -dimensional mental rotations. conclusions our experiment reveals that visual aesthetic appreciation involves high-level cognitive activity, both in women and men. given that differences appear from ms onwards, it seems that the brain activity identified in the present study cannot be reduced to simple perceptual processes. the main focus of activity in both sexes is in the parietal lobe. the parietal activity is bilateral in the case of women but lateralized to the right hemisphere in the case of men. the gender-related differences in the neural correlates of the aforementioned cognitive activity indicate that there might be different processing strategies for beauty in women and men. specifying these differential strat- egies remains to be ascertained. as we have argued, a possible explanation for the greater lateralization in men than in women could be grounded on differences between exploration strategies. women would carry out an exploration of categorical spatial relations. the processes occurring in the right hemisphere of male participants suggest an exploration strategy based on coordinate spatial relations. however, there are other alternatives to the interpretation based on spatial exploration strategies. it is generally accepted that the right parietal cortex is associated with global visual attention and the left with local attention. perhaps women make use of both global and local features in making their judgments, whereas men only rely on global features. another hypothesis could link our observations to language. women obtain higher scores on a diversity of verbal and language tasks ( ). perhaps women are more likely to associate the images with verbal labels than men, producing the lateralizing differences in neural activity. this hypothesis deserves further experimental work before seriously being taken into consideration. even though the specific cognitive processes related with the appreciation of beauty are still to be determined, we propose an explanation for the evolutionary features of such capacity related with sexual selection. silverman’s and eals’s ( ) hunter-gatherer hypothesis of gender differences in spatial abilities provides the most convincing scenario. differences in spatial ability between men and women would be associated with the division of labor between the sexes in hunting and gathering. in any case, given that parietal spatial-processing streams show certain derived traits present only in our species, it seems quite probable that gender-related differences in this pathway appeared after the human and chimpanzee lineages split. methods subjects. ten female and male neurobiology students (average age . years for women, . years for men) at the universidad complutense (madrid), with no previous training or special interest in art, volunteered to participate in this study. they all had normal or corrected vision and normal color vision. all were right-handed. all participants gave informed consent. stimuli. all participants were presented with the same set of photographs of either artistic paintings or natural objects, divided into groups: (i) pictures of abstract art; (ii) pictures of classic art; (iii) pictures of impressionist art; (iv) pictures of postimpressionist art; (v) photographs of landscapes, artifacts, urban scenes, and the like (true-life pictures from the master clips premium image collection, imsi, san rafael, ca; the book boring postcards, london, phaidon press; and photographs taken by us). the artistic styles were decided following the collection movements in modern art from the tate gallery, london, but we added european paintings of the xvii and xviii centuries and popular art pictures, like halloween and christmas cards. the objective was to present to the subjects a variety of artistic styles to increase their range of aesthetic judgment. to avoid the activation of facial-recognition brain mecha- nisms, pictures containing close views of humans were not included. four differ- ent sets of stimuli ( artistic and natural) were used for the participants’ preliminary training. observations. all stimuli were adjusted to the same resolution ( pixels per inch) and dimensions ( � cm). they were homogenized by operations (see for additional details). first, a behavioral test of semantic judgment was per- formed to assess the effect of pictorial complexity in aesthetic perception ( – ). stimuli were shown to voluntary subjects (undergraduate university students) on the screen of a macintosh powerpc, asking the subjects to score a picture’s complexity from to . all pictures receiving a mean � . points were discarded. second, the color spectrum of the visual stimuli was adjusted. we analyzed stimuli selected in the previous step, measuring their color spectrum by means of photoshop (adobe systems) run on a macintosh power mac g . third, the light reflected by stimuli was measured, in a dark room, by means of a minolta auto meter iv f digital photometer placed cm from the screen with an accessory to ° reflected light. stimuli � lux and � lux were discarded. a total of stimuli reasonably homogenized in regards to pictorial complexity, color spectrum, luminosity, and light reflection were thus obtained. technique. the technique used to register brain activity was magnetoencepha- lography (meg). participants received a short briefing about the technique and the aesthetic preference task they were required to carry out before entering the meg isolated room. half of the male and half of the female participants were asked to indicate, by raising a finger, that they found the image to be beautiful. the other half of the participants were asked to raise a finger if they although the image was not beautiful. we found no differences in the frequencies of beautiful and not-beautiful judgments between the sexes. [� ( ) � . , p � . ]. after the meg session, each participant performed a behavioral test. they were asked to rate the beauty of each of the same stimuli that they saw previously on a to likert scale. we assayed the differences between men and women’s ratings of the stimuli by means of student’s t tests. there were no significant differences between men and women’s beauty ratings for any of the stimuli. the details of the observations are posted at http://evocog.es/ index.php?option�com�content&view�category&layout�blog&id� & itemid� . image acquisition. the methods underlying meg data collection and analysis are described in maestu et al. ( ) and are outlined only briefly here. meg recordings were made with a whole-head neuromagnetometer (magnes wh, -d neuroimaging) consisting of magnetometer coils. the instrument is housed in a magnetically shielded room designed to reduce environmental magnetic noise that might interfere with biological signals. the variables taken into ac- count in the meg protocol and the procedure were the following: . signal analysis. the meg signal was filtered ‘‘online’’ with a bandpass filter set between . and hz, and digitalized with a sampling rate of hz, during a time window of , ms including a ms prestimulus period. the epoch data obtained for each participant were baseline-corrected and noise-reduced. each single trial event-related field was visually assessed to reject those exhibiting eye movements, blinks, or movement artifacts. artifact-free epochs of each channel and subject were averaged across each condition. the minimum number of trials obtained after artifact rejection was . . source analyses. the mne procedure, commonly used in meg source recon- struction and described in detail elsewhere ( ), was used for estimating the cortical origin of the brain response. because meg sources are believed to be restricted to the pyramidal neurons of the cortex ( ), the dipoles of the source space model were restricted to a cortical surface extracted from a structural mri. a tessellated cortical mesh template surface derived from the montreal neurological institute (mni) phantom brain ( ) and implemented in spm (www.fil.ion.ucl.ac.uk/spm/software/spm ) served as a brain model to esti- mate the current source distribution. typically the dipoles of the distributed cela-conde et al. pnas � march , � vol. � no. � p sy c h o lo g y ev o lu ti o n d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , source model are evenly placed at each node of the mesh representing the white/gray matter interface ( ). the spm template used contained , dipole locations. this dipole mesh was used to calculate the forward solution using a spherical head model. a spherical head model is known to be sufficient to estimate a good approximation of the physical head properties and to compute the magnetic field propagation of the forward model ( ). the inverse solution (the estimation of the current source density based on the meg topography) was calculated using the l minimum norm solution imple- mented in ‘‘in-house matlab-code.’’ to estimate the underlying current source density (the source strength at each node of the mni phantom brain) of the evoked field, the mne was computed for each time point, subject, and condition. finally, for each subject and condition, the mne solutions were divided in -ms steps and averaged across the time windows. the resulting mne averages were submitted to statistical parametric mapping analysis. data analysis. the images were analyzed by means of the spm (statistical parametric mapping) software, implemented on matlab . , using the mod- ule m/eeg. the experimental design included an intersubject variable (gen- der) and an intrasubject variable (aesthetic preference, with the levels beau- tiful and not beautiful). differences between the levels were contrasted by means of t tests (implemented on spm ) with a p � . (t � . ) with no adjustment to control. the extent threshold was set to k � voxels. the statistically significantly differences found correspond to: (i) brain activity in females when comparing beautiful and not-beautiful stimuli; (ii) brain activity in males when comparing beautiful and not-beautiful stimuli. acknowledgments. we thank drs. antonio damasio and oshin vartanian for comments on the manuscript and museo del prado (madrid, spain) for kind permission to use the pictures of stimuli in our study. this work was supported by r�d projects of the spanish ministerio de educación y ciencia um - / fiso, sej - /psic, and fis- - r�d, as well as by european com- misssion project gaba (fp -nest contract ). . kawabata h, zeki s ( ) neural correlates of beauty. j neurophysiol : – . . vartanian o, goel v ( ) neuroanatomical correlates of aesthetic preference for paintings. neuroreport : – . . cela-conde cj, et al. 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also engages with debates on the relationship between political economy approaches, and those concerned with culture and identity, and considers questions of production as well as consumption. both paula black and merl storr provide accounts of empirical research on women’s experiences of the fashion and beauty industries: they point to the complex and ambivalent nature of these social spaces as sites where femininity is constructed, and is also a source of pleasure. in the dialogue section, rita rupal gives a personal account of her experience of beauty parlors in india. rachel moseley brings into this discussion the role of a female star as fashion icon, with her analysis of audrey hepburn’s film roles, and of women’s responses to them. responses to the incorporation of ‘other’ cultures and styles within the fashion industry are explored by nirmal puwar in her discussion of a different sense of aesthetics and memory. pursuing the theme of the aesthetics of the everyday, joy gregory’s images question the politics and pleasures of being blonde. the dynamics of the fashion industry are addressed by angela mcrobbie, who provides a critical analysis of current trends, focusing on the conflict between the creative economy and neo-liberal globalization. elizabeth wilson’s review of the ‘radical fashion’ exhibition at the victoria and albert museum in london in raises the related question of the roles played by haute couture and high street fashion. in her dialogue piece, juliet ash gives an example of an attempt to counteract the effects of globalized production by a group of asian women textile workers in east london. finally, the review of the ‘stitched up’ exhibition shown in leamington spa, uk, points to the questions that need to be asked if production and consumption are to be considered together. the images and texts that we have brought together here are an original and timely intervention in this crucial area for women and for feminist analysis. one of the particular contributions of this collection is a full engagement with the intersectionality of gender, ‘race’ and class in relation to experiences and structures of the fashion and beauty industries. lucy bland, lyn thomas, merl storr, nirmal puwar, rita rupal doi: . /palgrave.fr. editorial fashion and beauty�� jop_infinityr.pdf journal of pragmatics creating mathematical infinities: metaphor, blending, and the beauty of transfinite cardinals rafael e. núñez department of cognitive science university of california, san diego the infinite is one of the most intriguing ideas in which the human mind has ever engaged. full of paradoxes and controversies, it has raised fundamental issues in domains as diverse and profound as theology, physics, and philosophy. the infinite, an elusive and counterintuitive idea, has even played a central role in defining mathematics, a fundamental field of human intellectual inquiry characterized by precision, certainty, objectivity, and effectiveness in modeling our real finite world. particularly rich is the notion of actual infinity, that is, infinity seen as a “completed,” “realized” entity. this powerful notion has become so pervasive and fruitful in mathematics that if we decide to abolish it, most of mathematics as we know it would simply disappear, from infinitesimal calculus, to projective geometry, to set theory, to mention only a few. from the point of view of cognitive science, conceptual analysis, and cognitive semantics the study of mathematics, and of infinity in particular, raises several intriguing questions: how do we grasp the infinite if, after all, our bodies are finite, and so are our experiences and everything we encounter with our bodies? where does then the infinite come from? what cognitive mechanisms make it possible? how an elusive and paradoxical idea such as the infinite structures an objective and precise field such as i want to thank mark turner and an anonymous reviewer for valuable comments and suggestions. journal of pragmatics mathematics? why the various forms of infinities in mathematics have the exact conceptual structure they have? these, of course, are not simple questions. nor are they new questions. some of them have been already approached in the fields of philosophy, philosophy of mathematics, and formal logic for centuries. the problem, however, is that historically, these disciplines developed quite independently of the natural sciences, and of the necessity of looking at real empirical data involving, for instance, real human reasoning and conceptual development. as a result, when dealing with the nature and structure of mathematical concepts they fail to consider important constraints imposed by findings in the contemporary scientific study of the human mind, the human language, and their biological underpinnings. in philosophy and logic the study of the nature and the foundation of mathematical entities is often ultimately reduced to discussions over formal proofs and axiomatization. the contemporary scientific study of the mind tells us that human reasoning and conceptual structures are far from functioning in terms of formal proofs and axioms. therefore what we need in order to answer the above questions is to seriously take into account how the human mind works, and at the very least provide cognitively plausible answers, that eventually could be tested empirically. in this article, i intend to accomplish three things. first, i want to provide answers to the above questions based on findings in conceptual metaphor and blending theories, building on the work i have done in collaboration with george lakoff in the field of cognitive science of mathematics. in the process i’ll be using a technique we have called mathematical idea analysis (lakoff and núñez, ). second, i want to analyze a specific case of actual infinity, namely, transfinite cardinals, as conceived by one of the most imaginative and controversial characters in the history of mathematics, the th journal of pragmatics century mathematician georg cantor ( - ). as we will see later, cantor created a very precise and sophisticated hierarchy of infinities that opened up entire new fields in mathematics giving shape, among others, to modern set theory. many celebrated counterintuitive and paradoxical results follow from his work. in this article i will try to explain the cognitive reasons underlying such paradoxes. finally, i want to analyze what lakoff and i called the bmi -- the basic metaphor of infinity (lakoff & núñez, )-- in terms of a conceptual blend (fauconnier & turner, , ), more specifically, in terms of a double-scope blend. lakoff and i have hypothesized that the bmi is a human everyday conceptual mechanism, originally outside of mathematics, that is responsible for the creation of all kinds of mathematical actual infinities, such as points at infinity in projective and inversive geometry, infinite sums, mathematical induction, infinite sets, infinitesimal numbers, least upper bounds, and limits . we will see that, unlike in the domains of poetry, advertisement, music, and visual arts, in mathematics humans need to operate with very specific forms of conceptual mappings, which are highly normalized, precise, constrained, and remarkably stable. in this paper i will take the bmi to be a double-scope conceptual blend where “bmi” stands for the more generic term basic mapping of infinity. what is special about mathematics? mathematics is a very peculiar form of knowledge where the entities constituting the subject matter are not perceived through the senses, yet they are incredibly precise and amazingly stable. before discussing mathematical infinities and their conceptual the analysis of how exactly the bmi gives the precise inferentia l structure observed in these mathematical concepts lies outside the scope of this article. for details see lakoff and núñez, , chapters - . journal of pragmatics structure, it is important to step back for a moment, and make clear what is unique about mathematics in general, as a field of intellectual inquiry. in order to be precise and rigorous, our cognitive analysis will have to be constrained by the peculiarities of mathematics as a body of knowledge. this includes mathematical infinities. mathematics, distinguishes itself from other bodies of knowledge and human conceptual systems in that it is highly idealized and fundamentally abstract. no purely empirical methods of observation can be directly applied to mathematical entities. think, for instance, of a point, the simplest entity in the euclidean plane, which has only location but no dimension. how could you possibly test a conjecture about euclidean points by carrying out an experiment with real points if they don’t have dimension? and how could you empirically observe a line, if it only has length but no width? it is easy to see, how the same arguments apply to infinity. this, and other properties of mathematics give shape to the unique manner in which knowledge is gathered in this discipline. unlike science, where knowledge increases largely via careful empirical testing of hypotheses, in mathematics knowledge increases via proving theorems, and by carefully providing formal definitions and axioms. whereas in science after performing an experiment a scientist can declare that her hypothesis is confirmed with a % of confidence, a mathematician won’t be taken seriously if she announces, for instance, that “with % of confidence number x is prime.” the mathematician will need to prove with “absolute certainty” that number x is prime. an important consequence of proof-oriented deductive ways of gathering knowledge is that once a theorem is proved, it stays proved forever! this peculiar form of knowledge gathering in mathematics provides an amazingly stable conceptual system. journal of pragmatics besides stability, lakoff and núñez ( ) give a list of other basic properties of mathematics such as precision, consistency for any given subject matter, universality of fundamental results (such as “ + = ” which doesn’t change across time and communities), symbolizability of its subject matters via discrete well-defined signs, calculability and generalizability of results, and discoverability of new entailments (theorems) . any account of the nature of mathematics, philosophical, cognitive, or other, must take into account these properties. in our case, the task will be to show that there are ordinary human cognitive mechanisms, such as aspectual schemas, conceptual metaphors, and conceptual blends, which when combining in very specific ways and being highly normalized, constrained, and stable can give an account of transfinite numbers as a special case of mathematical actual infinity. at this point, and in order to avoid any misunderstandings about the goal of this article and of the nature of mathematical idea analysis, it is very important to make clear that: . a cognitive analysis that takes into account the properties of mathematics described above, and . the bodily- grounded nature of human cognitive mechanisms such as conceptual metaphors and conceptual blends, provides a non-arbitrary explanation of the nature of mathematics. this non-arbitrary approach radically differs from post- modern accounts, where mathematics is seen as an arbitrary social text or as a mere cultural artifact. the position we will endorse here lakoff & núñez ( ) also mention another very important property of mathematics, that of being effective as general tools for description, explanation, and prediction in a vast number of activities. this property, however, is less relevant when transfinite numbers are concerned since they were not meant to actually model real physical, chemical, or biological phenomena. journal of pragmatics recognizes the importance of culture and history in the emergence and development of mathematical ideas, but explicitly rejects the claim that mathematics is arbitrarily shaped by history and culture alone (for details see lakoff & núñez, , pp. - ). with this perspective in mind, we are now ready to approach infinity. potential and actual infinity investigations, speculations, and debates about the infinite go back to the pre-socratic philosophers. one of the first to rigorously invoke the infinite to deal with questions regarding the origin, nature, and limits of things in the universe was anaximander ( - bc). he saw in απειρον (apeiron), which literally means “unlimited,” the ultimate source of all things. arguing in opposition to thales of miletus (ca. -ca. bc), who had asserted that water was the basis of all things, anaximander defended the idea that the enormous variety of things in the universe must come from something less differentiated than water. for him, this primary source was eternal, boundless, endless, from where even opposites such as cold and hot originated. this primary source was apeiron. it was subject to neither old age nor decay, perpetually generating fresh materials and dissolving them. because of its very nature (i.e., unlimited) no limits could apply to apeiron, and therefore it was conceived as sourceless, without creation, and indestructible. later, aristotle ( - bc) referred back to anaximander, but with a very different view. one of the crucial problems raised by aristotle was the issue of exhaustion. giving the example of the collection of numbers, aristotle argued that the totality of numbers cannot be present in our thoughts. in generating, one by one, the list journal of pragmatics of numbers, we can’t ge nerate a completed list. there will always be a number that hasn’t been considered before. in his physics he argued that apeiron is not that thing outside of which there is nothing (i.e., exhausted), but outside of which there is always something (i.e., inexhaustible). therefore apeiron, the “unlimited,” cannot be seen as a completed totality. what is completed has an end, and the end is a limiting element. by its very meaning there is a lack of that limit in apeiron. with aristotle then, apeiron takes a negative connotation, due to its inherent incompleteness and non-actualizable potential. because it cannot actually be realized in a clearly defined form, apeiron became associated with the idea of “undefined.” moreover, in order to keep his fundamental tene t that the unknowable exists only as a potentiality, aristotle rejected altogether the existence of the actual infinite: anything beyond the power of comprehension was seen as beyond the realm of reality. in his physics, aristotle stated quite clearly that infinity should be considered as something that “has potential existence” but never as an actual realized thing. many analysts and historians consider this negative connotation to be the reason of the refusal of using actual infinity in greek mathematics (for details see zellini, ; and boyer, ). since the time of aristotle then, the infinite has been treated with extreme care. many greek thinkers considered the infinite as an undefined entity with no order, chaotic, unstructured. the infinite, therefore, was seen as an entity to be avoided in proper reasoning. this view dominated most of the debates (in europe) involving the infinite all the way up to the renaissance. in mathematics this was no exception and the distinction between potential and actual infinity has ever since been made, by readily accepting the former and by questioning or simply rejecting the latter. journal of pragmatics potential infinity is the kind of infinity characterized by an ongoing process repeated over and over without end. it occurs in mathematics all the time. for instance, it shows up when we think of the unending sequence of regular polygons with more and more sides (where the distance from the center to any of the vertices is constant). we start with a triangle, then a square, a pentagon, a hexagon, and so on. each polygon in the sequence has a successor and therefore there is the potential of extending the sequence again and again without end (figure ). the process, at any given stage encompasses only a final number of repetitions, but as a whole doesn’t have an end and therefore does not have a final resultant state. [insert figure about here] but more than potential infinity, what is really interesting and mathematically fruitful is the idea of actual infinity, which characterizes an infinite process as a realized thing. in this case, even though the process is in- finite, that is, it does not have and end, it is conceived as being “completed” and as having a final resultant state. following on the example of the sequence of regular polygons, we can focus our attention on certain aspects of the sequence and observe that because of the very specific way in which the sequence is built certain interesting things happen. after each iteration the number of sides grows by one, the sides become increasingly smaller, and the distance r from the center to the vertices remain constant. as we go on and on with the process the perimeter and the area of the polygon become closer and closer in value to π r and to π r , respectively, which correspond to the values of the perimeter and the area of a circle. journal of pragmatics thinking in terms of actual infinity imposes an end at infinity where the entire infinite sequence does have a final resultant state, namely a circle conceived as a regular polygon with an infinite number of sides (see figure ). this circle has all the prototypical properties circles have (i.e., area, perimeter, a center equidistant to all points on the circle, π being the ratio between the perimeter and the diameter, etc.) but conceptually it is a polygon. [insert figure about here] it is the fact that there is a final resultant state that makes actual infinity so rich and fruitful in mathematics. but it is also this same feature that has made the idea of actual infinity extremely controversial because it has often lead to contradictions, one of the worst evils in mathematics. a classic example is the “equation” k/ = ∞, where k is a constant. this “equation” is based on the idea that (when finite values are concerned) as the denominator gets progressively smaller the value of the fraction increases indefinitely. so at infinity the denominator is and the value of the fraction is ∞ (greater than any finite value). the problem is that accepting this result would also mean accepting that ( · ∞) = k, that is the multiplication of zero times infinity could be equal to any number. this, of course, doesn’t make any sense. becausee of contradictions like this one many brilliant mathematicians, such as galileo ( - ), carl friedrich gauss ( - ), agustin louis cauchy ( - ), karl weierstrass ( - ), henri poincaré ( - ), among others had energetically rejected actual infinity. gauss, for journal of pragmatics instance, in a letter to his colleague heinrich schumacher dated wrote (cited in dauben, , p. ): but concerning your proof, i must protest above all against your use of an infinite quantity as a completed one, which in mathematics is never allowed. the infinite is only a façon de parler, in which one properly speaks of limits. here, limits are taken to be magnitudes to which certain ratios may approach as closely as desired when others are permitted to increase indefinitely, and are thus instances of potential infinity. up to the th century there was a well-established consensus among mathematicians that at best actual infinity could provide some intuitive ideas when dealing with limits for instance (gauss’ façon de parler) but that no consistent and interesting mathematics could possibly come out of an infinity actually realized. george cantor, following some preliminary work by bernard bolzano ( - ) and richard dedekind ( - ) radically challenged this view, seeing in actual infinity a genuine mathematical entity. his controversial, unconventional, and highly disputed work generated amazing new mathematics. transfinite cardinals: the standard story the th century was a very productive period in the history of mathematics, one that saw fundamental developments such as non-euclidean geometries, and the so-called arithmetization of analysis. the latter, a program lead by karl weierstrass, richard dedekind, and others, intended to ban geometrical and dynamic intuition (thought to be the source of paradoxes) by reducing the whole field of calculus developed in the th journal of pragmatics century by newton and leibniz, into the realm of numbers. counting and focusing on discrete entities, like numbers, became essential. it is in this zeitgeist that georg cantor, originally interested in the study of trigonometric series and discontinuous functions, was brought into his development of transfinite numbers, dispelling well- establish views that abolish the use of actual infinities in mathematics. today, cantor is best known for the creation of a mathematical system where numbers of infinite magnitude define very precise hierarchies of infinities with a precise arithmetic, giving mathematical meaning to the idea of some infinities being greater than others. his work was highly controversial, produced many counter- intuitive results and for most of his professional life cantor had to struggle against heavy criticism (for an in depth analysis of cantor’s work and intellectual path, see ferreirós, , and dauben, ). a basic problem for cantor was to determine the number of elements in a set (which he called menge, aggregate). this is, of course, a trivial problem when one deals with finite sets, but when one deals with sets containing infinitely many elements, such as the set of counting numbers , , , … , (i.e., the set of so-called natural numbers) this is literally impossible. how do you count them if they are infinitely many? cantor focused on the fact that when comparing the relative size of finite sets, not only we can count their elements, but we can also set up pairs by matching the elements of the two sets. when two finite sets have the same number of elements, a one-to-one correspondence between them can be established. and conversely, when a one-to-one correspondence between two finite sets can be established we can conclude that they have the same number of elements. journal of pragmatics cantor elaborated on the idea of one-to-one correspondence so it would apply also to infinite sets in a precise way. he addressed questions such as: are there more natural numbers than even numbers? a similar question had already been asked in the first half of the th century by galileo, who observed that it was possible to match, one-by-one ad infinitum the natural numbers with their respective squares, but because the squares are contained in the collection of natural numbers they form a smaller collection than the natural numbers. facing this paradoxical situation galileo concluded that attributes such as “bigger than,” “smaller than,” or “equal to” shouldn’t be used to compare collections when one or both had infinitely many eleme nts. in the th century cantor could get around the “paradox” by building on the previous very creative though not well- recognized work by bernard bolzano and by richard dedekind. these two mathematicians were the first to conceive the possibility of matching the elements of an infinite set with one of its subsets as an essential property of infinite sets and not as a weird pathology. dedekind in fact, for whom infinite sets constituted perfectly acceptable objects of thought, provided for the first time in history a definition involving the infinite in positive terms (i.e., not in negative terms such as in- finite or non- finite). he stated (in modern terminology) that a set s is infinite if and only if there exists a proper subset s’of s such that the eleme nts of s’ can be put into one-to-one correspondence with those of s. only infinite sets have this important property (for historical and technical details, see ferreirós, ). [insert figure about here] journal of pragmatics with this background, cantor had the way paved for answering his question regarding the “size” of the sets of natural and even numbers. he then declared that “whenever two setsfinite or infinitecan be matched by a one-to-one correspondence, they have the same number of elements” (maor, , p. ). because such a correspondence between natural and even numbers, can be established (figure ) he concluded, there are just as many even numbers as there are natural numbers. in this framework, the fact that all even numbers are contained in the natural numbers (i.e., they constitute a proper subset of) doesn’t mean that the set of natural numbers is bigger. following dedekind’s definition above, that fact simply shows a property of infinite sets. and what about other kinds of infinite sets, with more challenging properties? could such sets be put in one-to-one correspondence with the natural numbers? for instance, natural numbers and even numbers can be ordered according to magnitude such that every member has a definite successor. so what about say, rationa l numbers, which don’t have this property? rational numbers are dense, that is, between any two rational numbers, even if they are extremely close, we can always find another rational number. rationals don’t have successors. the set of rational numbers seems to have infinitely many more elements than the naturals because not only we can find infinitely many rationals bigger or smaller than a given number (i.e., towards the right or the left of the number line, respectively), but also we can find infinitely many rationals in any portion of the number line defined by two rationals. is then the set of rationals bigger than the naturals? in order to try to establish a one-to-one correspondence between the rationals and the naturals one needs, first of all, to display both sets in some organized way. in the case journal of pragmatics of even and natural numbers that organization was provided by order of magnitude. but because rationals are dense they can’t be ordered by magnitude. cantor, however, found a way of displaying all rationals, one by one, in a clever infinite array. figure shows such array, which displays all possible fractions. fractions with numerator one are displayed in the first row, fractions with numerator two are in the second row, and so on. and similarly, fractions with denominator one are in the first column, fractions with denominator two in the second column, and so on. in cantor was able to show, with this array, and against his own intuition (!), that it was possible to establish a one-to-one correspondence between the rationals and the naturals. all you need to do is to assign a natural number to each fraction encountered along the path indicated in figure . the path covers all possible fractions going diagonally up and down ad infinitum . [insert figure about here] when such a correspondence is established between two infinite sets, cantor said that they have the same power (mächtigkeit) or cardinal number. he called the power of the set of natural numbers, ℵ , the smallest transfinite number (denoted with the first letter of the hebrew alphabet, aleph). today, infinite sets that can be put in a one-to-one correspondence with the natural numbers are said to be denumerable or countable, having cardinality ℵ . cantor’s next question was, are all infinite sets countable? towards the end of he found out that the answer was no. he was able to provide a proof that the real a rational number can be expressed by different fractions. for the purpose of the one-to-one correspondence only the simplest fraction denoting a rational is considered. for example, / , / , / , etc. are equivalent to / , and therefore they are skipped. journal of pragmatics numbers can’t be put into one-to-one correspondence with the natural numbers: the set of real numbers is not denumerable. later cantor gave a different, simpler proof, known today as the famous proof by diagonalization. he started by assuming that a correspondence between the natural numbers and the real numbers between zero and one was possible. since every real number has a unique non-terminating decimal representation he wrote down the correspondence as follows : → .a a a … → .a a a … → .a a a … … → …… the list, according to the original assumption includes all real numbers between and . he then showed that he could construct a real number that wasn’t included in the list, a number of the form .b b b … where the first digit b of this number would be different from a (the first digit of the first number in the list), the second digit b of the new number would be different from a (the second digit of the second number in the list), and so on. as a result, the new number .b b b …, which is bigger than zero but smaller than , would necessarily differ from any of the numbers in the list in at least one digit. the digit bk (the k-th digit of the new number) will always differ from the digit akk given by the diagonal (the k-th digit of the k-th number of the list). this leads to a contradiction since the original list was supposed to include all real numbers between and , and therefore the one-to-one correspondence between the naturals and the reals in the interval ( , ) can’t be established. since the naturals were a subset of the reals this means that the reals form a non-denumerable set which has a power higher than the naturals: a the proof requires that all real numbers in the list to be written as non-terminating decimals. for example, a fraction such as . should be written as . … journal of pragmatics transfinite cardinal number bigger than ℵ . cantor called it c, for the power of the continuum. but cantor’s work went beyond these two transfinite numbers, ℵ and c. he showed that in fact there is an entire infinite and very precise hierarchy of transfinite numbers. in order to do so cantor elaborated on the idea of power set (i.e., the set whose elements are all the subsets of the original set, including the empty set and the original set itself), observing that for finite sets when the original set has n elements, its power set has exactly n elements. cantor extended this idea to infinite sets showing that the power (cardinality) of the power set of natural numbers was exactly ℵ . this new set in turn formed a power set whose cardinality was ℵ , and so on. this remarkable result defined a whole infinite hierarchy of transfinite cardinals holding a precise greater than relationship: ℵ < ℵ < ℵ < … cantor was able to prove a further extraordinary result: the number of elements in the set of real numbers is the same as the number of elements in the power set of the natural numbers. in other words he proved the equation c = ℵ to be true, meaning that the number of points of the continuum provided by the real line had exactly ℵ points. but cantor didn’t stop there. he was also able to show an extremely counter- intuitive result : dimensionality of a space is not related with the numbers of points it contains. any tiny segment of the real line has the same number of points as the entire line, and the same as in the entire plane, the entire three-dimensional space, and in fact in any “hyper- space” with a denumerable number of dimensions. cantor added many more counter- intuitive and controversial results to his long list of achievements. he developed a very journal of pragmatics rich work on transfinite ordinals (see dauben , , and sondheimer & rogerson, ), and defined a precise arithmetic for tranfinite cardinals where unorthodox equations such as the following hold: ℵ + = + ℵ = ℵ ; ℵ + k = k + ℵ = ℵ , for any natural number k; ℵ + ℵ = ℵ ; ℵ ⋅ k = k ⋅ ℵ = ℵ , for any natural number k; ℵ ⋅ ℵ = ℵ ; (ℵ ) k = ℵ , for any natural number k. these equations represented an extraordinary improvement in approaching and studying the infinite when compared to the old and vague idea represented by the symbol ∞. with cantor infinite numbers acquired a precise meaning, and constituted the corner stone of the development of extremely creative, and ingenious new mathematics. realizing how deep and rich cantor’s work was, david hilbert, one of the greatest mathematicians of the last couple of centuries said “no one shall drive us fro the paradise cantor created for us.” so far, this is more or less a summarized version of the standard story about cantor’s transfinite cardinals as it is told in general books and articles on the history and philosophy of mathematics (see, for instance, boyer, ; dauben, ; klein, ; kramer, ; maor, , sondheimer & rogerson, ). let us now try to understand what is, from a cognitive perspective, the conceptual structure underlying cantor’s ingenious work. journal of pragmatics bmi and conceptual blending: the birth of actual infinities in order to understand the cognitive nature of actual infinity and the conceptual structure underlying transfinite cardinals, we need to refer to two main dimensions of human cognitive phenomena: one is aspect (comrie, ), as it has been studied in cognitive semantics, and the other one is the bmi (originally described in lakoff and núñez, , as the basic metaphor of infinity) and here treated as the basic mapping of infinity, a form of double-scope conceptual blend. both, aspect and the bmi, being bodily- grounded phenomena of human cognition provide the elements to understand how the embodied mind (johnson, ; varela, thompson and rosch, ) makes the infinite possible. aspect in cognitive semantics, aspectual systems characterize the structure of event concepts. the study of aspect allows us to understand, for instance, the cognitive structure of iterative actions (e.g., “breathing,” “tapping”) and continuous actions (e.g., “moving”) as they are manifested through language in everyday situations. aspect can tell us about the structure of actions that have inherent beginning and ending points (e.g., “jumping”), actions that have starting points only (e.g., “leaving”), and actions that have ending points only (e.g., “arriving”). when actions have ending points, they also have resultant states. for example, “arriving” (whose aspectual structure has an ending point) in i arrive at my parents’ house, implies that once the action is finished, i am located at my parents’ house. when actions don’t have ending points they don’t have resultant states. many dimensions of the structure of events can be studied through aspect. journal of pragmatics for the purpose of this article, the most important distinction regarding aspect is the one between perfective aspect and imperfective aspect. the former has inherent completion while the latter does not have inherent completion. for example, the prototypical structure of “jumping” has inherent completion, namely, when the subject performing the action touches the ground or some other surface. we say then that “jumping” has perfective aspect. “flying,” on the contrary, does not have inherent completion. the prototypical action of “flying” in itself does not define any specific end, and does not involve touching the ground. when the subject performing the action, however, touches the ground, the very act of touching puts an end to the action of flying but does not belong to “flying” itself. we say that “flying” has imperfective aspect. processes with imperfective aspect can be conceptualized both, as continuative (continuous) or iterative processes. the latter have intermediate endpoints and intermediate results. sometimes continuous processes can be conceptualized in iterative terms, and expressed in language in such a way. for example, we can express the idea of sleeping continuously by saying “he slept and slept and slept.” this doesn’t mean that he slept three times, but that he slept uninterruptedly. this human cognitive capacity of conceiving something continuous in iterative terms turns out to be very important when infinity is concerned. continuous processes without end (e.g., endless continuous monotone motion) can be conceptualized as if they were infinite iterative processes with intermediate endpoints and intermediate results (for details see lakoff & núñez, ). with these elements we can now try to understand how human cognitive mechanisms bring potential infinity into being. from the point of view of aspect, potential infinity involves processes that may or may not have a starting point, but that journal of pragmatics explicitly deny the possibility of having an end point. they have no completion, and no final resultant state. we arrive then to an important conclusion: • processes involved in potential infinity have imperfective aspect. bmi, the basic mapping of infinity now let’s analyze actual infinity, which is what we really care about in this article. it is here where the bmi becomes crucial. the bmi is a general conceptual mapping which is described in great detail elsewhere (lakoff & núñez, ). it occurs inside and outside of mathematics, but it is in the precise and rigorous field of mathematics that it can be best appreciated. lakoff and núñez have hypothesized that the bmi is a single human everyday conceptual mechanism that is responsible for the creation of all kinds of mathematical actual infinities, from points at infinity in projective geometry, to infinite sums, to infinite sets, and to infinitesimal numbers and limits. when seen as a double- scope conceptual blend the bmi has two input spaces. one is a space involving completed iterative processes (with perfective aspect). in mathematics, these processes correspond to those defined in the finite realm. the other input space involves endless iterative processes (with imperfective aspect), and therefore it characterizes processes involved in potential infinity. in the blended space what we have is the emergent inferential structure required to characterize processes involved in actual infinity. figure shows the correspondences between the input spaces and the projections towards the blended space. details of conceptual blending can be seen in other contributions in this v olume, and in the original work of fauconnier and turner ( , ). journal of pragmatics [insert figure about here] it is important to see that the richness and peculiarity of the bmi is its organization and structure as a double-scope blend (fauconnier & turner, ). the correspondence between the two input spaces involves all the elements with the exception of the very last one, the single element that distinguishes in a fundamental way a finite process from a potentially infinite process. this provides a major conflict: a clash between a characterization of a process as explicitly having an end and a final resultant state, and one as explicitly characterizing the process as being endless and with no final resultant state. often these conflicts lead to paralysis, where no blended space is formed at all, leaving the original input spaces as they were with their own local inferential structure. the history of science and mathematics provide many such examples. my interpretation, for instance, is that this is in part what occurred to galileo when he observed that natural numbers and even numbers could be put in one-to-one correspondence, but failed to make any conclusions that would have required completing and endless process . rather than paralysis, a double-scope blend handles the conflict in a creative way providing fundamentally new inferential structure in the blended space. in the bmi, this is what occurs: • from the completed iterative process input (with perfective aspect) the fact that the process must have an end and a final resultant state is profiled and projected to the blended space, ignoring the clause that the process must be finite. as we will see later, another important component contributing to his paralysis was, of course, that at that time he wasn’t able to operate with the conceptual metaphor same number is pairability, which is cantor’s metaphor. journal of pragmatics • and from the endless iterative processes (with imperfective aspect), the fact that the process has no end is profiled and projected into the blended space, ignoring the clause that the processes does not have a final resultant state. • as a result, in the blended space there is now new inferential structure, which provides an endless process with an end and a final resultant state. as lakoff & núñez ( ) have pointed out, a crucial entailment of the bmi is that the final resultant state is unique and follows every nonfinal state. the uniqueness comes from the input space of completed processes, where for any completed process the final resultant state is unique. the fact that the final resultant state is indeed final, means that there is no earlier final state. that is, there is no distinct previous state within the process that both follows the completion stage of the process yet precedes the final state of the process. similarly, there is no later final state of the process. that is, there is no other state of the process that both results from the completion of the process and follows the final state of the process. in order to illustrate how the bmi works, let’s take the example mentioned earlier of the sequence of regular polygons (figure ). as lakoff & núñez ( , chapter ) point out, in order to get from the bmi as a general cognitive mechanism to special cases of actual infinity, one needs to parameterize the mapping. that is, one must characterize precisely what are the elements under consideration in the iterative process. in our example the first input space (located on the left in figure ) provides a finite process with perfective aspect. the process is a specific sequence of regular polygons where the distance from the center to any of the vertices is kept constant. the process starts with a triangle, then a square, a pentagon, and so on, all the way to a polygon with a finite journal of pragmatics number of sides, say sides. at each stage, we have specific values for the perimeter and area of each polygon in the sequence, which get closer to π r, and π r , respectively (where r is the distance from the center to the vertices). the perimeter and the area of the final resultant state in this first input space (i.e., polygon with sides) has the closest values to π r, and π r , respectively. the second input space (located on the right in figure ), involves the sequence shown in figure , that is, an endless sequence of regular polygons (which has imperfective aspect). at each stage we obtain specific values for the perimeter and area of each polygon in the sequence, which get endlessly closer to π r, and π r , respectively. the distance from the center to any of the vertices is always constant, namely, r. there is no final resultant state in this second input space. in the blend, all the corresponding elements are projected, which gives us the sequence of regular polygons with a triangle, a square, a pentagon, and so on. the conflict between the final resultant state of a finite sequence of polygons (i.e., polygon of sides) and the endless nature of the sequence is handled by the double-scope blend to give an endless sequence of regular polygons with a final resultant state (with infinitely many sides). at this final resultant state no difference in terms of perimeter, area, and distance from center to vertices can be detected between the “final” polygon obtained via the bmi and a circle. for the circle the values of the perimeter, the area, and the radius are precisely π r, π r and r, respectively. therefore, when parameterized in this manner, the final resultant state is conceived as an actual unique polygon-circle: a very peculiar kind of polygon with an infinite number of sides, a distance from center to vertices equal to r, a perimeter equal to π r, and an area equal to π r . the bmi guarantees that this journal of pragmatics figure is unique and that is indeed the final resultant state. no polygon comes after the polygon-circle in the process. transfinite cardinals: the cognitive story it is now time to come back to cantor’s work by looking closely to one of his classic texts. here is cantor himself at the beginning of his contributions to the founding of the theory of transfinite numbers: every aggregate m has a definite “power,” which we will also call “cardinal number.” we will call by the name “power” or “ cardinal number” of m the general concept which, by means of our faculty of thought, arises from the aggregate m when we make abstraction of the nature of its various elements m and of the order in which they are given (p. ). by “aggregate” (menge) cantor means “any collection into a whole (zusammenfassung zu einem ganzen) m of definite and separate objects m of our intuition or our thought” (p. ) (for the purpose of this discussion, aggregates can be seen as collections or sets). the objects he refers to are the “elements” of m. cantor then defines the crucial concept that will allow him to build the notion of transfinite number, which as we will see is a metaphorical extension of cardinal numbers of finite aggregates. this is the idea of equivalence: we say that two aggregates m and n are “equivalent” … if it is possible to put them, by some law, in such a relation to one another that to every journal of pragmatics element of each one of them corresponds one and only one element of the other (p. ). with these extremely simple but powerful notions (i.e., aggregate, element, cardinal number, equivalence), cantor wants to build an entirely new theory of numbers that would encompass at the same time his transfinite numbers and the usual counting (natural) numbers. these are his own words: we will next show how the principles which we have laid down, and on which later on the theory of actually infinite or transfinite cardinal numbers will be built, afford also the most natural, shortest, and most rigorous foundation for the theory of finite numbers (p. - ). this is a crucial passage. cantor is explicitly telling us that he is not only concerned with actual infinity. but, why someone interested in infinity would attempt to give rigorous foundations to finite numbers as well? the reason is simple. he has a more ambitious goal: to generalize in a rigorous way the very notion of number in itself! he wants to do this by building transfinite and finite numbers, using the same principles. cantor proceeds by building the natural numbers from scratch: to a single thing e , if we subsume it under the concept of an aggregate e = (e ), corresponds as cardinal number what we call “one” and denote by … let us now unite with e another thing e , and call the union-aggregate e , so that e = (e , e ) = (e , e ). the cardinal number of e is called “two” and is denoted by … by addition of new elements we get the series of aggregates e = (e , e ), e = (e , e ), ... which give us journal of pragmatics successively, in unlimited sequence, the other so-called “finite cardinal numbers” denoted by , , , … (p. ). notice that each finite aggregate en = (en- , en), and it has cardinality (n + ). because en is formed via the union of the predecessor en- with the “thing” en, this implies that en- is contained in (using modern terminology we would say, “is a proper subset of”) en. the series of aggregates is constructed exhibiting a nested structure (under the relation of being a proper subset of) where the difference between any two consecutive aggregates en and en- is just the “thing” en, being their cardinal numbers (n + ) and n, respectively. cantor then is able to state a (apparently naïve but) very important theorem: • the terms of the unlimited series of finite cardinal numbers , , , …, ν… are all different from one another, “that is to say, the condition of equivalence established [earlier] is not fulfilled for the corresponding aggregates” (p. ; our emphasis). when finite natural numbers are concerned this theorem is innocuous and it seems to be totally irrelevant. basically, it says that the number is different from the number , and that they are different from the number , and so on. the theorem is simply telling us that the cardinal number of two finite sets are different if the sets cannot be put into one-to- one correspondence (i.e., they are not equivalent). this is a simple fact, but it has profound consequences: from this conceptualization, the number and the number , for instance, are different, not because the latter is the result of counting an aggregate with “three” elements, while the former is the result of counting an aggregate with only “two,” but because the aggregates from which they are cardinal numbers of cannot be put in a one-to-on correspondence (i.e., they do not fulfill the condition of equivalence). the real journal of pragmatics power of the notion of equivalence and of this theorem becomes visible when he finally introduces the smallest transfinite cardinal number aleph-zero: the first example of a transfinite aggregate is given by the totality of the finite cardinal numbers ν; we call its cardinal number “aleph-zero” and denote it by ℵ … that ℵ is a transfinite number, that is to say, is not equal to any finite number µ, follows from the simple fact that, if to the aggregate {ν} is added a new element e , the union aggregate ({ν}, e ) is equivalent to the original aggregate {ν}. for we can think of this reciprocally univocal correspondence between them: to the element e of the first corresponds the element of the second, and to the element ν of the first corresponds the element ν+ of the other. … we thus have ℵ + = ℵ (p. - ) this is another crucial passage. it constitutes one of the first moments in history in which a (rather uno rthodox but) well-defined equation involving infinite quantities is established. extending the nested construction of the series of finite aggregates, where en = (en- , en), he now builds the aggregate ({ν}, e ) by adding the element e to {ν}, the infinite aggregate containing all finite cardinal numbers. but an important difference with the finite cases emerges: although {ν} is contained in ({ν}, e ) (i.e., it is a proper subset of), now these two aggregates do fulfill the conditions of equivalence (i.e., they can be put in a one-to-one correspondence). some fundamental entailments follow: . a finite number k and the transfinite number ℵ are different, not because the latter is the result of counting the aggregate of all finite cardinal numbers, while journal of pragmatics the former is the result of counting an aggregate with only “k” elements, but because the aggregates from which they are cardinal numbers of cannot be put in a one-to-on correspondence (i.e., they do not fulfill the condition of equivalence). . the transfinite numbers ℵ and ℵ + are equal, not because the latter is the result of counting the aggregate of all finite cardinal numbers, while the former is the result of counting the same aggregate plus one element, but because the aggregates from which they are cardinal numbers of can be put in a one-to-on correspondence (i.e., they do fulfill the condition of equivalence). . these criteria for discriminating finite numbers from transfinite ones, are consistent with richard dedekind’s revolutionary definition of infinite sets mentioned earlier: a set s is infinite if and only if there exists a proper subset s’of s such that the elements of s’ can be put into one-to-one correspondence with those of s. what has cantor done with this new “generalized” notion of number? a could such a generalization apply in a consistent way to finite and infinite numbers? what are the major implicit cognitive steps he has gone through? with the cognitive tools described in the previous section we can now analyze the conceptual structure underlying cantor’s transfinite cardinals. ) cantor’s metaphor: same number as is pairability in order to characterize his notion of power (mächtigkeit), or cardinal number, for infinite sets (or aggregates, mengen), cantor makes use of a very important conceptual metaphor: same number as is pairability (equivalence) (for details, see lakoff & núñez, journal of pragmatics ). this metaphor allows him to create the conceptual apparatus for giving a precise metaphorical meaning to the comparison of number of elements (i.e., power, cardinality) of infinite sets. this is how this works. the everyday notions of “same numbers as” and “more than” are, of course, based on the experience we have with finite –not infinite– collections. the following are everyday (non- formal) characterizations of these finite notions: • same number as: a (finite) collection (or aggregate) a has the same number of elements as (a finite) collection b if, for every member of a, you can take away a corresponding member of b and not have any members of b left over. • more than: a (finite) collection (or aggregate) b has more elements than (a finite) collction a if, for every member of a, you can take away a member of b and still have members left in b. if collection a happens to be contained in (is a proper subset of) b, the sub-collection of elements left over after the matching is equal to the sub-collection of elements in b that are not in a. there is nothing uncontroversial about these everyday notions, to the point that we totally take them for granted. in fact, decades ago, the swiss psychologist jean piaget described in detail how these fundamental notions get organized quite early in children’s cognitive development without explicit goal-oriented education (piaget, , núñez, ). so, if we extend the left-over idea to infinite cases, and approach the question “are there more natural numbers than even numbers?” equipped exclusively with the ordinary notions of “same number as” and “more than,” the answer is straightforward. we can match the elements of both sets as shown in figure and arrive to the conclusion that there are indeed more natural numbers, because there are the odd numbers left over. following the journal of pragmatics previous characterization of “more than,” the collection of even numbers is contained in (is a proper subset of) the collection of natural numbers, and therefore what is left over after the matching corresponds to the sub-collection of elements in the natural numbers that are not in the collection of even numbers. this is nothing other than the sub- collection of odd numbers. in this sense an answer based on a natural notion of “more than” is unambiguous. [insert figure about here] but, it is true that the two sets, if arranged properly, are also pairable (equivalent) in the sense that we can put them in a one-to-one correspondence as shown earlier in figure . pairability and “same number as,” however, are two very different ideas. they do have the same extension for finite collections, as cantor carefully pointed out when constructing the natural numbers from scratch (i.e., they cover the same cases giving the same results). however, they are cognitively different and their inferential structures differ in important ways. in his investigations into the properties of infinite sets, cantor used the concept of pairability (equivalence) in place of our everyday concept of same number as. in doing so, and by implicitly dropping the “left-over” idea, he established a conceptual metaphor, in which one concept (same number as) is conceptualized in terms of the other (pairability). figure shows the mapping of cantor’s simple but crucial conceptual metaphor. [insert figure about here] journal of pragmatics it is very important to understand that this new conception of number is metaphorical in nature. by simply being able to establish pairability one doesn’t get too far. as we said earlier, this is exactly what happened to the brilliant galileo two centuries before cantor. in order to be able to extend the notion of cardinality from finite sets, which we can literally count, to infinite sets, which we cannot literally count, we do need to actively and fully ignore the “left over” clause embedded in the ordinary notion of “more than.” only then we can go on with the metaphorical extension to conceive cardinality for infinite sets. we often see in mathematics books, textbooks, and articles statements like “cantor proved that there are just as many positive even integers as natural numbers.” according to a cognitive account of our ordinary notion of “as many as” cantor proved no such thing. what cantor did was simply to prove that the sets were pairable (assuming, via the bmi, that you can pair all of the natural numbers with their corresponding even integers). it is only via cantor’s metaphor that it makes sense to say that he “proved” that there are, metaphorically, “just as many” even numbers as natural numbers. unfortunately, many mathematics texts ignore the metaphorical nature of cantor’s new meaning given to the idea of pairability, ascribing to it a kind of transcendental truth, and failing to see its truth as derived from a very human conceptual metaphor. as a consequence, they often conclude that there is something fundamentally wrong with human intuition when dealing with infinity. consider for instance the following citation: journal of pragmatics “would it be possible, for example, to match on a one to one basis the set of all counting numbers with the set of all even numbers? at first thought this seems impossible, since there seem to be twice as many counting numbers as there are even numbers. and yet, if we arrange all the even numbers in a row according to their magnitude, then this very act already shows that such a matching is possible … so our intuition was wrong!” (maor, , p. , our emphasis). the same applies to views within mathematics regarding the role of everyday language. consider the following citation concerning the problem of comparing similar infinite sets: “the confusions and apparent paradoxes in this subject arise from the transfer of everyday language, acquired from experience with finite collections, to infinite sets where we must train ourselves to work strictly with the mathematical rules of the game even though they lead to surprising results.” (sondheimer & rogerson, , p. ). our cognitive analysis shows that there is nothing wrong with our “intuition” per se. and there is nothing wrong with “everyday language” either. extensive work in cognitive linguistics shows that conceptual metaphor and conceptual blending are not mere linguistic phenomena, but they are about thought and cognition. in the practice of mathematics what is often called “intuition” or naïve ideas expressed by “everyday language” are in fact very well organized conceptual structures based on bodily- grounded systems of ideas with very precise inferential structures. but in mathematics, often what counts as primary are the “strict” and rigorous “mathematical rules” (which from a cognitive perspective need to be explained as well!). “intuition” and “everyday language” are seen as vague and imprecise (for further discussion of this and its implications for journal of pragmatics formal programs in mathematics see núñez & lakoff, ; núñez & lakoff, submitted). consider this other statement: “[cantor concluded,] there are just as many even numbers as there are counting numbers, just as many squares as counting numbers, and just as many integers (positive and negative) as counting numbers” (maor, , p. ). in our ordinary conceptual system, this is not true. not because our intuition is wrong, or because our everyday language is imprecise and vague, but because it is an inference made within a different conceptual structure with a different inferential structure. according to our ordinary notion of “more than” there are indeed more natural numbers than there are positive even integers or squares. and there are more integers than there are natural numbers. there is a precise cognitively-structured logic underlying this inference, which we can make as rigorous as we want. lack of rigor, then, is not the issue. this of course doesn’t lessen cantor’s brilliant results. cantor’s ingenious metaphorical extension of the concept of pairability and his application of it to infinite sets constitutes an extraordinary conceptual achievement in mathematics. what he did in the process was create a new technical mathematical concept—pairability (equivalence)—and with it, new mathematics.this new mathematics couldn’t have been invented only with our everyday ordinary notions of “same number as” and “more than.” but, as we saw above in cantor’s original text (and presumably for ideological and philosophical reasons), cantor also intended pairability to be a literal generalization of the very idea of number. an extension of our ordinary notion of “same number as” from finite to infinite sets (for historical details see ferreirós, ). there cantor was journal of pragmatics mistaken. from a cognitive perspective, it is a metaphorical rather than literal extension of our very precise everyday concept. ) the bmi and the proof of rationals denumerability as we saw earlier, cantor provided a very simple, elegant, and powerful proof of the possibility of establishing a one-to-one correspondence between the natural numbers and a dense set such as the rational numbers. what is rarely mentioned in mathematics texts (to say the least) is that this proof makes implicit use of human cognitive mechanisms such as conceptual metaphor and blending. consider cantor’s infinite array of fractions shown in figure . there the bmi is used over and over, implicitly and unconsciously, in comprehending the diagram. it is used in each row of the array, for assuring that all fractions are included. first, the bmi is used in the first row for assuring that all fractions with numerator one are included in a completed collection, without missing a single one. then, the bmi is used to assure that all fractions with numerator two are actually included, and so on. in the same way, the bmi is implicitly used in each column of the array to assure that all fractions with denominator one, two, three, and so on, are actually included in this infinite array providing completion to it. finally, the bmi is used in conceptualizing the endless arrow covering a completed path. the arrow covers every single fraction in the array assuring, via the bmi, the possibility of the one-to-one correspondence between all rationals and naturals. the bmi together with cantor’s metaphor discussed earlier validate the diagram as a proof that the natural numbers and the rational numbers can be put into one-to-one correspondence and therefore have the same power—that is, the same cardinality. journal of pragmatics ) the bmi in cantor’s diagonal proof of the non-denumerability of real numbers cantor’s celebrated diagonal proof also makes implicit use of the bmi. first, there is the use of the special case of the bmi for infinite decimals. each line, is of the form .aj aj aj …., where j is a natural number denoting the number of the line. thanks to the bmi each of these unending lines can be conceived as being completed. it is important to remind that cantor’s diagonal proof requires that all real numbers in the list to be written as non-terminating decimals, which provide another name for the same number. it is the bmi that allows a fraction like . (with terminating decimals) to be conceived and written as . … a non-terminating –yet completed-- decimal. second, there is the use of the special case of the bmi for the set of all natural numbers. each row corresponds to a natural number, and all of them must be there. this provides the conditions for testing the assumed denumerability of the real numbers between zero and one. third, the proof (which works by reductio ad absurdum) assumes that all real numbers between zero and one are included in the list. this provides the essential condition for the success of the proof because it guarantees that there is a contradiction if a number is constructed that is not included in the originally assumed completed list. this is indeed the case of the new constructed number .b b b …. fourth, there is the sequence along the diagonal formed by the digits of the form ajk where j = k. it, too, is assumed to include all such digits on the diagonal. the fact that all real numbers must be written as non-terminating decimals guarantees that a digit ajk when j = k (on the diagonal) is not a part of an endless sequences of zeroes (i.e., an endless sequence of zeroes for digits ajk when j < k, which would be the case of a fraction such as . …). this is another implicit use of the bmi. and finally, there is the process of constructing the new number .b b b … by journal of pragmatics replacing each digit ajk (with j = k on the diagonal) with another digit. the process is unending, but must cover the whole diagonal, and must create the new real number, not included in the original list, written as a non-terminating—yet complete--decimal. another implicit special case of the bmi. conclusion in this article i have briefly introduced one aspect of george cantor’s creative work-- transfinite cardinals--and i have analyzed some of his celebrated counterintuitive and paradoxical results. counter- intuitive ideas and paradoxes are very interesting and fertile subject matters for cognitive studies because they allow us to understand human abstraction through conflicting conceptual structures. from the point of view of cognitive science, especially from cognitive linguistics and mathematical idea analysis, it is possible to clarify what makes cantor’s results counterintuitive. these analyses show also that, contrary to many mathematicians’ and philosophers of mathematics’ beliefs, the nature of potential and actual infinity can be understood not in terms of transcendental (or platonic) truths, or in terms of formal logic, but in terms of human ideas, and human cognitive mechanisms. among the most important mechanisms for understanding the cognitive nature of transfinite cardinals and actual infinities are: • aspectual systems; with iterative and continuative processes, perfective and imperfective structures with initial states, resultant states, and so on. • conceptual metaphors, such as cantor’s metaphor same number as is pairability. journal of pragmatics • conceptual blending, such as the multiple implicit uses of the bmi, the basic mapping of infinity, in cantor’s proofs. these mechanisms are not mathematical in themselves. they are human embodied cognitive mechanisms, realized and constrained by the peculiarities of human bodies and brains. transfinite cardinals are the result of a masterful combination of conceptual metaphor and conceptual blending done by the extremely creative mind of georg cantor, who worked in a very prolific period in the history of mathematics. these ideas and the underlying cognitive mechanisms involved in cantor’s work, are bodily- grounded and not arbitrary. that they are not arbitrary is a very important point that often gets confused in the mathematical and sometimes the philosophical communities where human-based mechanisms are often taken to be mere “social conventions.” what is ignored is that species-specific bodily-based phenomena provides a biological ground for social conventions to take place. this ground, however, is not arbitrary. it is in fact constrained by biological phenomena such as morphology, neuroanatomy, and the complexity of the human nervous system (varela, thompson, and rosch, ; thelen & smith, ; núñez & freeman, ). abundant literature in conceptual metaphor and blending tells us that source and target domains, input spaces, mappings, and projections are realized and constrained by bodily- grounded experience such as thermic experience, visual perception and spatial experience (johnson, ; lakoff, ). in the case of transfinite numbers these constraints are provided by container-schemas for understanding (finite) collections and their hierarchies, genetically-determined basic quantity-discrimination mechanisms (e.g., subitizing), visual and kinesthesic experience journal of pragmatics involved in size comparison and the matching of elements, correlates between motor control and aspect, and so on (for details see lakoff & núñez, , chapter ). the strong biological constraints operating on these mechanisms provide very specific inferential structures which are very different from non (or weakly) constrained “social conventions” like the color of dollar bills or the font used in stop signs. these non- arbitrary cognitive mechanisms, which are essential for the understanding of conceptual structures, can be studied empirically and stated precisely, and cognitive science techniques such as mathematical idea analysis can serve this purpose. in this article, i mainly referred to transfinite cardinals, as an example of a very rich and interesting case of actual infinity. but this is only one case. lakoff and núñez ( ) have shown that there are many other instantiations of actual infinity in mathematics realized via the bmi, such as points at infinity in projective and inversive geometry, infinite sets, limits, transfinite ordinals, infinitesimals, and least- upper bounds. what is important to make clear about these mathematical infinities is the following: . they belong to completely different fields within mathematics. . they have, from a purely mathematical point of view, their existence guaranteed by very specific tailor- made axioms in various fields. in set theory, for instance, one can make use of infinite sets simply because there is a specific axiom, the axiom of infinity, that grants their existence. the existence of other mathematical actual infinities in other fields is guaranteed by similar axioms. with this in mind, we can now see the relevance of the bmi: • it explains with a single mechanism cases of actual infinity occurring in different non-related mathematical fields. whereas in mathematics actual infinities are journal of pragmatics characterized by different sets of axioms in different fields, cognitively, they can be characterized by a single cognitive mechanism: the bmi. • it provides a cognitively plausible explanation of the nature of actual infinity that is constrained by what is known in the scientific study of human cognition, human conceptual structures, human language, and the peculiarities of the human body and brain. mathematical axioms, don’t have to comply any constraints of this kind, because they only operate within mathematics itself. therefore, axioms can’t provide explanations of the nature of transfinite cardinals, actual infinities, or, for that matter, of mathematical concepts in general. the bmi, along with other cognitive mechanisms, such as conceptual metaphors and the use of aspect, allows us to appreciate the beauty of transfinite cardinals, and to see that the portrait of infinity has a human face. references boyer, c. ( ). the history of the calculus and its conceptual development. new york: dover. boyer, c. ( ). a history of mathematics. new york: john wiley & sons. cantor, g. ( / ). contributions to the founding of the theory of transfinite numbers. new york: dover. comrie, b. ( ). aspect: an introduction to the study of verbal aspect and related problems. cambridge textbooks in linguistics. new york: cambridge university press. journal of pragmatics dauben, j.w. ( ). georg cantor and the origins of transfinite set theory. scientific american, june: – . dauben, j.w. ( ). georg cantor: his mathematics and philosophy of the infinite. princeton, nj: princeton university press. fauconnier, g. & m. turner ( ). conceptual integration networks. cognitive science, ( ): – . fauconnier, g. & m. turner ( ). the way we think. conceptual blending and the mind’s hidden complexities. new york: basic books. ferreirós, j. ( ). labyrinth of thought: a history of set theory and its role in modern mathematics. boston: birkhäuser. klein, m. ( ). mathematical thought from ancient to modern times. new york: oxford university press. kramer, e. ( ). the nature and growth of modern mathematics. princeton, nj: princeton university press. lakoff, g. & r. núñez. ( ). where mathematics comes from: how the embodied mind brings mathematics into being. new york: basic books. maor, e. ( ). to infinity and beyond: a cultural history of the infinite. princeton, nj: princeton university press. núñez, r. ( ). en deçà du transfini: aspects psychocognitifs sous-jacents au concept d’infini en mathématiques. fribourg: university of fribourg press. núñez, r. & g. lakoff ( ). what did weierstrass really define? the cognitive structure of natural and ε-δ continuity. mathematical cognition, ( ): - . journal of pragmatics núñez, r. & g. lakoff (submitted). an invitation to the cognitive science of mathematics. the mathematical intelligencer. núñez, r. & w. freeman (eds.) ( ). reclaiming cognition: the primacy of action, inteention, and emotion. thorverton, uk: imprint academic. piaget, j. ( ). the child’s conception of number. new york: w.w. norton. sondheimer, e. & a. rogerson ( ). numbers and infinity. a historical account of mathematical concepts. cambridge, ma: cambridge university press. thelen, e. & l. smith ( ). a dynamic systems approach to the development of cognition and action. cambridge, ma: mit press. varela, f., thompson, e., & e. rosch ( ). the embodied mind: cognitive science and human experience. cambridge, ma: mit press. zellini, p. ( ). breve storia dell’infinito. milano: adelphi edizioni. journal of pragmatics figure . a case of potential infinity: the sequence of regular polygons with n sides, starting with n = (assuming that the distance from the center to any of the vertices is constant). this is an unending sequence, with no polygon characterizing an ultimate result. figure . a case of actual infinity: the sequence of regular polygons with n sides, starting with n = (assuming that the distance from the center to any of the vertices is constant). the sequence is endless but it is conceived as being completed. the final resultant state is a very peculiar entity, namely, a circle conceived as a polygon with infinitely many sides of infinitely small magnitude. figure . a mapping establishing the one-to-one correspondence between the sets of natural and even numbers. … … natural numbers even numbers … … journal of pragmatics figure . cantor’s infinite array of rational numbers conceived for the proof of their denumerability. each fraction covered by the arrow can be mapped to a natural number thus establishing a one-to-one correspondence between the natural and the rational numbers. / / / / … / / / / … / / / / … / / / / … … … journal of pragmatics figure . the bmi, the basic mapping of infinity, as a double-scope conceptual blend. the beginning state state resulting from the initial stage of the process the process: from a given intermediate state, produce the next state the intermediate result after that iteration of the process process with end and final resultant state the beginning state state resulting from the initial stage of the process the process: from a given intermediate state, produce the next statethe intermediate result after that iteration of the process process with no end the beginning state state resulting from the initial stage of the process the process: from a given intermediate state, produce the next statethe intermediate result after that iteration of the process process with no end with final resultant state completed iterative processes (perfective aspect) finite processes endless iterative processes (imperfective aspect) potential infinity blended space actual infinity entailment: the final resultant state is unique and follows every nonfinal state journal of pragmatics figure . a mapping between the natural and even numbers based on the ordinary notion of “same as” and “more than.” the mapping shows that one can pair elements of the two collections and have the odd numbers left over (shown with a circle). the entailment of this natural mode of reasoning is that there are more natural numbers than even numbers. figure . georg cantor’s fundamental conceptual metaphor same number as is pairability. this simple but ingenious metaphor is at the core of transfinite numbers and modern set theory. natural numbers even numbers … … source domain mappings target domain numeration set a and set b can be put into - correspondence set a and set b can’t be put in - correspondence, and set a is a proper subset of b. set a and set b have the same number of elements set b is larger than set a. it has more elements than set a. rev. virtual quim. |vol | |no. | | - | artigo a beleza, a popularidade, a toxicidade e a importância econômica de espécies de aráceas santos, a. p. b.* rev. virtual quim., , ( ), - . data de publicação na web: de setembro de http://www.uff.br/rvq the beauty, popularity, toxicity and economic importance of araceae species abstract: the family has subfamilies, genera and approximately species in several tropical and subtropical regions worldwide. also known as aroid, contains the most diverse and attractive species of the plant kingdom. although several species are cultivated as ornamental plants all the year are recorded numerous cases of poisoning by plants all brazil, where the species of the araceae family are among those responsible. the genera dieffenbachia, colocasia, philodendron, anthurium and caladium, illustrate how they are popular in our daily life, and limited information about the chemical composition and toxicity of some of these plants is one more reason to act with caution to grow them as ornamentals. keywords: araceae, diffenbachia, colocasia, philodendron, anthurium, caladium. resumo a família araceae apresenta subfamílias, gêneros e aproximadamente espécies distribuídas em diversas regiões tropicais e subtropicais em todo o mundo. as aráceas estão entre as mais diversificadas e atraentes espécies do reino vegetal. apesar de várias espécies serem cultivadas como plantas ornamentais, no brasil são registrados inúmeros casos, todos os anos, de intoxicação por espécies da família araceae. plantas dos gêneros dieffenbachia, colocasia, philodendron, anthurium e caladium são populares em nosso cotidiano, e o número limitado de informações a respeito da composição química e toxicidade de algumas destas plantas é mais um motivo para agir com precaução ao cultivá-las como ornamentais. palavras-chave: araceae, diffenbachia, colocasia, philodendron, anthurium, caladium. * instituto de química, bloco a, centro de tecnologia, cidade universitária, universidade federal do rio de janeiro, - , rio de janeiro - rj, brasil. apcanela@yahoo.com.br doi: . / - . http://www.uff.br/rvq mailto:apcanela@yahoo.com.br http://dx.doi.org/ . / - . volume , número revista virtual de química issn - julho-setembro rev. virtual quim. |vol | |no. | | - | a beleza, a popularidade, a toxicidade e a importância econômica de espécies de aráceas ana paula b. dos santos* instituto de química, bloco a, centro de tecnologia, cidade universitária, universidade federal do rio de janeiro, - , rio de janeiro - rj, brasil. *apcanela@yahoo.com.br recebido em de julho de . aceito para publicação em de agosto de . introdução: a família araceae . o gênero dieffenbachia . o gênero colocasia . o gênero philodendron . o gênero anthurium . o gênero caladium . conclusão . introdução: a família araceae a família araceae encontra-se distribuída em regiões tropicais e subtropicais da américa, África e sudoeste da Ásia, arquipélago malaio, madagascar e ilhas seychelles. - características dos trópicos, as espécies da família araceae são pouco frequentes em regiões frias, desenvolvendo-se melhor em temperaturas entre e ºc, à exceção da zantedeschia aethiopica (ex. gênero calla), que resiste a temperaturas inferiores a ºc. elas apresentam-se em variadas formas, ervas, trepadeiras, geófitas (caule tuberoso e subterrâneo), epífitas (sobre plantas), rupícolas (sobre rochas), reófitas (plantas resistentes a correntes aquáticas) e helófitas (plantas que crescem ao longo ou as margens de rios). - caracterizadas como monocotiledôneas, estas plantas pertencem ao grupo de angiospermas cujo embrião possui um único cotilédone (primeiras folhas que surgem dos embriões. , são plantas de caule herbáceo, às vezes lenhoso, curto nas espécies terrestres e pantanosas, longo e escandente (com brotos para o alto) nas epífitas. as folhas são grandes, membranáceas a coriáceas, inteiras ou partidas, com disposição alternada, nervação reticulada, paralela ou colocasioide. em grande parte das espécies terrestres ou pantanosas, os caules são tuberosos, grandes e ricos em amido. nas ascendentes e epífitas (as raízes) são adventícias (brotamento de raiz a partir do caule). as flores dispõem-se em uma espiga espessa, a espádice, que é envolvida por uma folha modificada, a espata, frequentemente de cores vivas. a espata pode ser plana ou fechada dividida em tubo e lâmina ao redor da base da espádice. as flores podem ser unissexuais ou hermafroditas, sésseis (sem hastes, inseridas na espádice) e muito pequenas. , taxonomicamente, a família araceae pertence à ordem alismatales e dentre as famílias desta ordem, ocupa uma posição chave na compreensão da evolução das monocotiledôneas. apesar do grande número de espécies, grande variedade de formas e ampla distribuição geográfica, a origem e a evolução da família araceae são pouco conhecidas por causa da dificuldade de fossilização das suas espécies. macrofósseis mostram que a família araceae era mailto:apcanela@yahoo.com.br santos, a. p. b. rev. virtual quim. |vol | |no. | | - | bastante diversificada e avançada pelo período terciário ( a , milhões de anos, abrangendo as épocas paleoceno, eoceno, oligoceno, mioceno e plioceno). além disto, sua grande diversidade e a estrutura subfamiliar complexa, predominantemente tropical, sugerem que esta família teve origem e dispersou-se em áreas de baixa altitude. a idade mínima da origem da família araceae estimada pela análise molecular calibrada com fósseis é de - milhões de anos. , a classificação da família araceae reduz-se, principalmente, às escolas de schott e engler (tiveram várias outras, culminando no trabalho de mayo, ). heinrich wilhelm schott foi o primeiro botânico a realizar, em , a classificação botânica da família araceae, agrupando as espécies em gêneros. em , o número de gêneros foi elevado para , seguindo os mesmos fundamentos de classificação. , a primeira classificação de engler ( ) é semelhante à atual, exceto que reconhecia subfamílias no lugar das atuais. pela primeira vez o gênero pistia foi incluído como uma arácea e lemnoideae como uma subfamília de araceae (excluída pela classificação de hooker). o sistema engler foi refinado em subsequentes publicações, ul i a do o das pftanzenreich t a alho fi al mais importante da família. a família araceae é constituída atualmente por subfamílias (gymnostachydoideae, pothoideae, oronthioideae, lasioideae, lemnoideae, philodendroideae, pistioideae e zamioculcadoideae), gêneros e aproximadamente espécies. , no brasil são encontradas cerca de espécies, distribuídas em gêneros, dentre esses: bognera, dracontioides, gearum e zomicarpa endêmicos, além de outros com distribuição mais ampla como philodendron e anthurium. , , as aráceas apresentam folhagens de grande diversidade, que as tornam uma das plantas mais populares e belas do reino vegetal. a família araceae tem grande importância no setor de florístico e paisagístico, e está presente também no setor de alimentos. na medicina popular são descritas diversas aplicações para o uso de algumas espécies tais como contraceptivo, no tratamento de doenças reumáticas e da pele, contra vermes intestinais, mordedura de cobra e hemorroidas. apesar disto, algumas subfamílias são citadas como responsáveis por acidentes tóxicos, inclusive letais, tais como: pothoideae, lasioideade, philodendroideae. dentre as razões para o aumento no número de acidentes, estão o uso de espécies como medicamentos sem conhecimento prévio, troca de espécies alimentícias por outras semelhantes (impróprias para o consumo) e a presença de exemplares como plantas ornamentais no interior de residências. , apesar de a toxicidade ser uma das principais características da família araceae, os constituintes químicos responsáveis pelos efeitos tóxicos ainda são, em sua maior parte, desconhecidos. inicialmente, alguns autores atribuíram os mecanismos tóxicos a ação das ráfides de oxalato de cálcio. - hoje, já se sabe que esta substância participa do mecanismo tóxico provocando uma lesão e expondo o organismo do individuo à substância tóxica. , os efeitos ocasionados pela intoxicação por espécies da família araceae decorrentes do contato com a mucosa bucal incluem queimação e dor na cavidade oral, acarretando o desenvolvimento de edema de lábios e língua com excessiva salivação. em alguns casos pode ocorrer dificuldade de respiração e da fala, que pode evoluir para um edema de glote e provocar a morte da vítima por asfixia. além disto, o contato com os olhos pode provocar dor intensa, lacrimejamento, inflamação da pálpebra, contração súbita do músculo ocular e posterior fotofobia. , - nos últimos anos, o número de acidentes por intoxicação com plantas tóxicas, sobretudo com crianças, tem se mantido elevado devido ao hábito da população de cultivar plantas ornamentais no interior de residências, escolas e locais públicos. o sinitox (sistema nacional de informações tóxico- farmacológicas) tem a função de coordenar a coleta, a compilação, a análise e a divulgação dos casos de intoxicação e envenenamento notificados nos estados brasileiros. este órgão publicou recentemente o número de casos de intoxicação por plantas no brasil no período de a , de acordo com a faixa etária e a região do país, como ilustram as tabelas e gráficos e . dados epidemiológicos mostram as espécies pertencentes a família araceae como uma das principais responsáveis pela intoxicação em todo o mundo, e apontam a dieffenbachia picta (comigo- ninguém-pode) e o caladium bicolor (tinhorão) como duas das espécies mais tóxicas desta família. santos, a. p. b. rev. virtual quim. |vol | |no. | | - | tabela . número de casos de intoxicação por plantas por faixa etária no brasil entre e idade /anos < - - - - - - - - - - > ign total anos total *ign: ignorado gráfico . número de casos de intoxicação por plantas por faixa etária no brasil entre e tabela : número de casos de intoxicação por plantas por região do brasil entre e . região /anos norte nordeste sudeste sul centro-oeste brasil anos total santos, a. p. b. rev. virtual quim. |vol | |no. | | - | gráfico . número de casos de intoxicação por plantas por região do brasil entre e . o gênero dieffenbachia o gênero dieffenbachia foi descrito em por schott com uma única espécie baseada na caladium seguinum previamente descrita como arum seguine. as próximas espécies foram descritas no peru como d. humilis, d. macrophylla e d. obliqua. representado por aproximadamente espécies, sua distribuição não é uniforme e o maior centro de diversidade inclui a colômbia com espécies, equador ( ), peru ( ), brasil ( ), panamá ( ) e costa rica ( ). , as espécies deste gênero podem atingir até metros de altura, com caule em formato cilíndrico com até centímetros de diâmetro. de coloração verde, as folhas crescem de a cm e apresentam manchas irregulares em tons creme. , , figura . dieffenbachia picta embora as dieffenbachia possuam propriedades tóxicas e irritantes, estão descritas algumas aplicações e usos populares para as plantas deste gênero. as folhas e o suco de espécies de dieffenbachia foram utilizados externamente no tratamento de pruridos, inflamações, gota, impotência sexual, frigidez e hanseníase. habitantes masculinos de uma ilha do caribe mastigavam a d. seguine para se tornarem estéreis durante o intervalo de e horas. os índios do alto amazonas utilizavam extratos de folha e caule de d. seguine em combinação com o curare como veneno em flechas. na jamaica, os escravos eram obrigados a mastigar pedaços de caule de espécies deste gênero como forma de punição. , , figura : dieffenbachia seguine o gênero dieffenbachia é um dos mais populares e tóxicos da família araceae. os nomes populares do g e o tó i o du a e – cana do mudo – inglês, co igo-ninguém-pode – português) denunciam os riscos do contato com espécies deste gênero. , , a literatura descreve várias hipóteses sobre a natureza química do princípio tóxico das espécies de dieffenbachia, que incluem alcaloides, ácidos graxos, esteroides, terpenos, polissacarídeos, glicosídeos santos, a. p. b. rev. virtual quim. |vol | |no. | | - | cianogênicos e saponinas. , , , - além disto, alguns autores acreditavam que a toxicidade de algumas espécies de dieffenbachia estava associada a enzimas proteolíticas como a dumbcaína e ao aminoácido asparagina, porém ensaios realizados não apresentaram resultados conclusivos a respeito da substância tóxica. , devido à semelhança com o processo alérgico (coceira, dor e sintomas similares) causado pelos pelos da vagem de mucuna pruriens (do inglês cowhage), devido a presença da enzima proteolítica mucunaíma, alguns autores sugerem a participação de proteínas no processo edematogênico das dieffenbachia. venenos de cobra e de escorpião também contêm enzimas proteolíticas. estas enzimas são responsáveis pelo latejamento, dor, edema, necrose local e trombose vascular causados por algumas aráceas. enzimas proteolíticas produzem uma variedade de efeitos tais como: exudação do plasma para dentro dos tecidos, fibrinólise, produção de plasmina, bradicinina e tripsina. também estão envolvidas na produção de cininas associadas ao mecanismo tóxico das dieffenbachia que levam à redução da pressão sanguínea, contração do músculo liso intestinal e vasodilatação. os estudos fitoquímicos e toxicológicos voltados para a identificação do princípio ativo ainda são limitados e inconclusivos. atualmente, as espécies de dieffenbachia são freqüentemente cultivadas como plantas ornamentais, principalmente na decoração de ambientes internos devido a adaptabilidade à baixa luminosidade, sendo facilmente encontradas em residências e locais públicos. , esta característica tem aumentado o número de intoxicações em pessoas e animais, tornando assim, importante o conhecimento sobre o mecanismo tóxico dessas plantas. . o gênero colocasia devido a semelhança existente entre os tubérculos de dioscorea sp. e colocasia esculenta é comum ambos serem chamados popularmente por inhame, mesmo no meio científico. as publicações nacionais ilustram a confusão quanto à definição da te i ologia do i ha e , a á e ta o , dificultando a identificação correta das espécies. entre e um grupo internacional definiu os descritores para as duas espécies em todo o mundo. nas publicações do international plant genetic resouces institute (ipgre : ) ficou estabelecido que as espécies do gênero dioscorea se ia o he idas po i ha e a e a colocasia esculenta seria deno i ada po ta o . figura . colocasia esculenta e tubérculo de taro. , apesar da padronização, a denominação popular de taro é ainda dada a quatro espécies da família araceae: colocasia esculenta, cyrtosperma chamissonis, xanthosoma sagittifolium e alocasia macrorrhizos. dentre elas, a colocasia esculenta e xanthosoma sagittifolium são amplamente cultivados nos trópicos porque suas raízes e tubérculos são alimentos básicos em muitas partes da África, américa, pacífico e Ásia. o sucesso destas culturas ocorre nos trópicos úmidos e subúmidos, os quais não estão disponíveis para outras culturas. - o taro (colocasia esculenta), também conhecido por taioba, cocoyam ou dasheen e originário da Índia, é bastante consumido no hawaii, japão, egito, gana e santos, a. p. b. rev. virtual quim. |vol | |no. | | - | nigéria. muitos botânicos a consideram uma espécie polimórfica, com muitas variedades, tais como colocasia esculenta var. esculenta e var. antiquorum. a xanthosoma sagitifolium é conhecida popularmente por tannia, além de cocoyam e tem sua origem na américa tropical. , a colocasia esculenta possui um longo caule subterrâneo, denominado cormo, que acumula carboidratos e proteínas de reserva para a formação de uma nova planta. esta espécie se adapta muito bem ao clima tropical, sendo capaz de se desenvolver em condições adversas como em solos pobres, com excesso de água, com sombreamento e sob estresse climático. devido à esta fácil adaptabilidade e a resistência a pragas e doenças, o cultivo desta espécie tem baixo custo de produção além de apresentar elevado rendimento por unidade de área. seus tubérculos são de fácil conservação e alto valor nutritivo, tornando o taro, dentre outros tubérculos, uma cultura alternativa para reforçar a base alimentar em países em desenvolvimento. , dentre as raízes e tubérculos, o taro ocupou, em , o º lugar em volume de produção no mundo, tendo menor produtividade que a batata e o inhame como mostram os gráficos a seguir. os gráficos ilustram também que uma grande parcela do taro e do inhame produzido no mundo se deve a contribuição da África. apesar da elevada produção do tubérculo neste continente e seu cultivo ser conhecido por séculos, no sul da África seu consumo é negligenciado. considerado alimento para as populações pobres, os agricultores não demonstram interesse pelo seu cultivo apesar de seu elevado valor nutricional. gráfico . Área plantada, produção, produtividade de taro, inhame, mandioca e batata no mundo e na África em e os tubérculos da taioba (cocoyam) podem ser consumidos cozidos, guisados, fritos ou triturados em pasta e misturados a sopa, além de serem encontrados na forma de papas de aveia, farinhas ou hips . co o as atatas, o tu ulo pode se transformado em vários alimentos e produtos para alimentação animal e insumos industriais. as folhas também podem ser consumidas. a farinha destes tubérculos pode se tornar uma boa fonte de amido, não somente para a produção de alimentos, mas, também, para indústrias de drogas, têxtil, papel e produção de petróleo. santos, a. p. b. rev. virtual quim. |vol | |no. | | - | os tubérculos são de fácil digestão e são conhecidos por apresentarem proteínas, vitamina c, tiamina, riboflavina e niacina. os carboidratos, fonte de energia, são o principal nutriente fornecido pelas taiobas, assim como acontece na maior parte dos tubérculos. além disto, como em muitas raízes e tubérculos, as taiobas são deficientes em vitaminas e minerais, mas apresentam quantidades significantes de fibras. as taiobas, porém, contêm fatores antinutricionais, isto é, substâncias como oxalatos, inibidores de proteinases, fitatos, taninos, alcaloides, esteroides e glicosídeos cianogênicos. os oxalatos agem como um mecanismo de defesa, além de atuarem como reserva de cálcio. fitatos regulam a disponibilidade de cálcio, magnésio, ferro e fósforo na formação de substâncias insolúveis. taninos formam complexos com proteínas e reduzem sua digestão e palatabilidade. sua absorção no intestino provoca possíveis efeitos carcinogênicos através da interferência com a absorção de ferro. substâncias esteroidais como as sapogeninas e saponinas podem causar paralisia e morte. a fim de remover os antinutrientes nocivos a saúde, é necessário aquecer os tubérculos. o cozimento aumenta a digestabilidade, promove a palatabilidade e torna o alimento mais seguro para a alimentação. contudo, o cozimento pode reduzir o valor nutritivo, tendo como resultado perda e alteração das propriedades alimentares como redução da composição mineral. a maioria dos cultivares de taro tem um sabor picante e podem causar inchaço dos lábios, boca e garganta se consumidos crus. este efeito é causado pela presença de cristais de oxalato de cálcio que penetram na pele, causando a sensação de picada. como na dieffenbachia, na colocasia esculenta a substância responsável pelo efeito irritante parece ser uma proteína presente nas suas raízes e folhas. , o cozimento reduz o efeito irritante causado pela c. esculenta porque afeta a solubilidade, e reduz o oxalato solúvel presente no alimento se a água do cozimento for descartada. em contraste, assar o tubérculo provoca a concentração de oxalatos no alimento devido a perda de água por evaporação. a biodisponibilidade dos oxalatos pode ser alterada pela adição extra de cálcio a partir do leite ou de derivados do leite. experimentos demonstraram que a biodisponibilidade do oxalato pode ser reduzida a ze o se o a tu ulo de oxalis tuberosa) for assada e comida com creme azedo. além disto, a adição de leite de coco ou de uma mistura de leite:leite de coco % com folhas de taro cozidas reduziu a presença de oxalato na urina de voluntários. o taro é um alimento básico amplamente consumido nas ilhas do pacífico e também tem um mercado emergente na nova zelândia. torna-se evidente a importância do estudo dos mecanismos de absorção não somente de oxalato, mas de todos os fatores antinutricionais que acarretam a redução da sua qualidade. . o gênero philodendron o gênero philodendron é o segundo maior gênero da família araceae. nativas da américa tropical, as mais de espécies deste gênero estão espalhadas pelo mundo. aproximadamente representantes destas espécies ocorrem no brasil. pertencente a subfamília philodendroideae, a qual inclui a tribo philodendreae, suas espécies estão divididas nos subgêneros meconostigma, pteromischum e philodendron, bem distintos em morfologia floral e vegetativa, anatomia floral e distribuição geográfica. , - figura . philodendron gloriosum o gênero neotropical philodendron é um dos mais importantes na família araceae, não somente em termos de representatividade, mas também pela sua importância para a floricultura como planta ornamental, devido à beleza de sua folhagem. típico da floresta tropical, este gênero constitui um dos mais conhecidos e notáveis dentre as aráceas devido a sua abundância, e por apresentar folhas grandes, vistosas e trepadeiras. o gênero philodendron pode ocorrer em vários tipos de habitats entre os quais brejos, afloramentos rochosos e até em regiões semi-áridas. grande parte da diversidade deste gênero ocorre em regiões pouco conhecidas da américa tropical como, por exemplo, chocó na colômbia, peru subandino, equador e a santos, a. p. b. rev. virtual quim. |vol | |no. | | - | parte ocidental da planície amazônica. , , são descritas algumas aplicações na medicina popular para algumas espécies de philodendron, dentre elas o uso como purgartivo, diurético, bactericida, antiprotozoário, anti-hidrópico e adstringente, sendo útil no tratamento de bronquite crônica e aguda, reumatismo, úlceras, erisipela, otites, edemas e epidermites. , a atividade bactericida do p. amurense foi atribuída a presença de limonoides. além disto, há relatos na literatura da atividade contra trypanossoma cruzi e trichomonas vaginalis de extratos de várias espécies, dentre elas philodendron bipinnatifidum. contudo, seu uso exige cuidado devido a presença de substâncias que causam irritação na pele. encontradas em várias espécies do gênero philodendron, as substâncias responsáveis pelo efeito alergênico têm sido associadas à presença dos resorcinóis, meta di- hidroxibenzenos com cadeia lateral com diferentes graus de insaturação. a realização da cromatografia em coluna possibilitou a identificação de -( z, z- heptadecadienil) resorcinol, - heneicosatetraenilresorcinol em p. scandens e - pentadecenilresorcinol, -heptadecadienilresorcinol em p. lacerum. estudos químicos com cipó de p. scabrum permitiram o isolamento do alquilresorcinol -hexadecanoil- , -dihidroxibenzeno. , em função da semelhança estrutural com catecóis, espera-se que o efeito irritante dos resorcinóis aumente com o aumento da cadeia lateral, bem como com o aumento das insaturações. , , foi relatada também a presença de poliprenoides, esteroides e estig aste o a, al de i istoleato de etila, α- bisabolol, isopalmitato de etila e palmitato de etila, constituinte majoritário de philodendron imbe. figura . estrutura do alquilresorcinol -hexadecanoil- , -dihidroxibenzeno lamarck descreveu pela primeira vez há mais de anos que a planta termogênica lírio arum (zantedeschia - araceae) poderia aquecer suas flores a mais de dez graus acima da temperatura ambiente e concomitantemente exalar um odor desagradável. a termogênese ocorre em órgãos reprodutivos de várias famílias de plantas como araceae, annonaceae, arecaceae, cycadaceae, cyclanthaceae, magnoliaceae, nymphaeaceae e zamiaceae dentre as famílias de plantas termogênicas. trata-se de subproduto da atividade bioquímica metabólica e uma propriedade fisiológica das flores que está, geralmente, associada à polinização. inflorescências termogênicas podem, em poucas horas, dias ou semanas, aquecer-se até - ºc como em arum dioscoridis e philodendron bipinnatifidum. o aquecimento está geralmente associado a emissão de odor e a liberação de pólen, e liga-se à presença de polinizadores. , substâncias como alcenos alifáticos ( -deceno, dimetil-octadieno), ésteres (butirato de metila, laurato de isopropila), cetonas ( -metil- - butanona, -heptanona), álcoois (propanol), aldeídos (nonanal, decanal), benzenoides (p-cresol, álcool e zíli o , te pe oides li o e o, β-pineno) estão associadas ao odor emitido por espécies dos gêneros arum e dioscorea. diversas espécies têm sido intensamente estudadas em função de seus graus de aquecimento, metabolismo, duração e período do fenômeno, a produção de odor e a relação com polinizadores. dentre as características das plantas termogênicas está a capacidade de regular sua temperatura, independente da temperatura ambiente, em poucas horas, como por exemplo, , ºc em philodendron melinonii. , , a inflorescência nas aráceas é tipicamente composta por um espádice, constituído por uma espiga, na qual estão inseridas as flores rodeadas por folhas modificadas, a espata. a espádice apresenta flores unissexuais femininas e masculinas. as flores femininas estão dispostas na base e as masculinas na parte superior e geralmente são separadas por uma zona de flores estéreis masculinas. na subfamília aroideae, o calor é geralmente produzido pelas flores do sexo masculino (férteis ou estéreis). , - no espádice, a temperatura aumenta até - ºc durante as primeiras noites de florescimento, através de uma via alternativa respiratória mitocondrial, que envolve uma oxidase resistente ao cianeto. , , um dos aspectos mais importantes da termogênese foi descrito pela primeira vez, em , em philodendron bipinnatifidum quando suas flores exibiram a capacidade de regulação da temperatura, aumentando a respiração e a produção de calor, atingindo, na primeira noite, temperaturas entre a ºc. entre a primeira e segunda noite, a produção de santos, a. p. b. rev. virtual quim. |vol | |no. | | - | calor começou a se reduzir, mas manteve-se regulada entre e ºc, reduzindo-se na segunda noite. padrão similar de termogênese é observado para várias espécies de philodendron (p. solimoesense) com um primeiro evento de termogênese mais intenso na primeira noite, e um segundo menos intenso na segunda noite, podendo ocorrer pequenos eventos entre os dois picos (p. acutatum, p. pedatum, p. melinonii e p. squamiferum). as flores de araceae são interessantes não apenas porque produzem calor, mas porque são capazes de regular sua temperatura, variando a taxa de produção de calor de forma inversa à temperatura do ambiente e do ar. desta maneira, é importante estudar o fenômeno da termogênese buscando a compreensão de fatores que favorecem a polinização, ainda pouco estudados. . o gênero anthurium o gênero anthurium com cerca de espécies é o maior da família araceae. pertencente a subfamília pothoideae e a tribo potheae, está subdividido em seções. o gênero anthurium ocorre essencialmente na américa tropical, onde pode ser encontrado do méxico até a argentina, ocorrendo nas ilhas do caribe, panamá, colômbia, equador, brasil, argentina e uruguai. o gênero ocorre em todo o brasil sendo representado por cerca de espécies, das quais no estado de são paulo. , - o gênero distribui-se com bastante diversidade em matas úmidas tropicais de baixas e médias elevações, em florestas nebulares, em áreas brejosas, sobre afloramentos rochosos, áreas arenosas abertas e em regiões semi-áridas. as espécies são hemiepífitas trepadeiras, terrestres, epífitas, litófitas (crescem sobre as rochas), raramente helófitas ou reófitas (margens ou ilhas rochosas de rios). o gênero anthurium com cerca de espécies é o maior da família araceae. pertencente a subfamília pothoideae e a tribo potheae, está subdividido em seções. o gênero anthurium ocorre essencialmente na américa tropical, onde pode ser encontrado do méxico até a argentina, ocorrendo nas ilhas do caribe, panamá, colômbia, equador, brasil, argentina e uruguai. o gênero ocorre em todo o brasil sendo representado por cerca de espécies, das quais no estado de são paulo. , - o gênero distribui-se com bastante diversidade em matas úmidas tropicais de baixas e médias elevações, em florestas nebulares, em áreas brejosas, sobre afloramentos rochosos, áreas arenosas abertas e em regiões semi-áridas. as espécies são hemiepífitas trepadeiras, terrestres, epífitas, litófitas (crescem sobre as rochas), raramente helófitas ou reófitas (margens ou ilhas rochosas de rios). figura . anthurium andraeanum o anthurium é uma planta semi-herbácea, ereta, com caule e entrenós curtos variando de , a , m de altura. seu ciclo de vida é longo (perene). apresenta folhas verdes, vistosas, lanceoladas (mais longas que largas) com base geralmente agudas e cuneadas (forma de cunha) com numerosas nervuras secundárias e terciárias. a inflorescência é caracterizada pela presença de espatas de cores variadas de acordo com o cultivar. , extratos de anthurium schlechtendalli inibiram o crescimento de células hl- , revelando a atividade antileucêmica desta espécie. a medicina popular tem descrito o uso das folhas de espécies do anthurium como anti-inflamatória. segura e cols., descreveram a atividade anti-inflamatória dos extratos em diclorometano e em etanol do anthurium cerrocampanense. o estudo fitoquímico do extrato em butanol de folhas de anthurium versicolor revelou a presença do constituinte majoritário epolamida, além de flavonóis (dentre eles vitexina), do ácido rosmarínico, dentre outros. a atividade antioxidante foi atribuída ao conjunto de compostos fenólicos presentes no extrato butanólico. - o anthurium é uma planta semi-herbácea, ereta, com caule e entrenós curtos variando de , a , m de altura. seu ciclo de vida é longo (perene). apresenta folhas verdes, vistosas, lanceoladas (mais santos, a. p. b. rev. virtual quim. |vol | |no. | | - | longas que largas) com base geralmente agudas e cuneadas (forma de cunha) com numerosas nervuras secundárias e terciárias. a inflorescência é caracterizada pela presença de espatas de cores variadas de acordo com o cultivar. , extratos de anthurium schlechtendalli inibiram o crescimento de células hl- , revelando a atividade antileucêmica desta espécie. a medicina popular tem descrito o uso das folhas de espécies do anthurium como anti-inflamatória. segura e cols., descreveram a atividade anti-inflamatória dos extratos em diclorometano e em etanol do anthurium cerrocampanense. o estudo fitoquímico do extrato em butanol de folhas de anthurium versicolor revelou a presença do constituinte majoritário epolamida, além de flavonóis (dentre eles vitexina), do ácido rosmarínico, dentre outros. a atividade antioxidante foi atribuída ao conjunto de compostos fenólicos presentes no extrato butanólico. - figura . estrutura da vitexina a produção de flores de corte desempenha um papel importante na diversificação da agricultura tropical. no mercado global, o anthurium depois das orquídeas, são as flores tropicais de corte mais comercializadas. no brasil, esta espécie também se destaca na produção de folhas e flores de corte e para o cultivo em vaso. devido ao importante papel das plantas ornamentais na diversificação da agricultura tropical é importante conhecer as características de crescimento e desenvolvimento dessas espécies para melhorar seu potencial produtivo. a produção comercial do anthurium está focada principalmente nas espécies anthurium andraeanum e anthurium scherzerianum. as características de boa qualidade dos cultivares caracterizam-se por qualidade da folha, haste floral ereta, firme e medindo cm, com boa produção; espata com brilho, aberta, de textura firme e coloração uniforme; espádice ligeiramente arqueada com cerca de / do comprimento da espata; durabilidade pós-colheita e resistência a doenças. , , figura . anthurium scherzerianum embora a produção comercial do anthurium esteja voltada principalmente para as espécies de anthurium andraeanum e anthurium scherzerianum, a indústria de flores de corte depende de cultivares de elite e de híbridos de anthurium andraeanum que, por sua vez, dependem da disponibilidade de clones. a propagação vegetativa convencional do anthurium através de plantas recém desenvolvidas leva anos para desenvolver quantidades significativas de clones com qualidade comercial. a propagação de híbridos é difícil devido ao desenvolvimento de um baixo número de plantas. a propagação de sementes não é vantajosa por causa da possibilidade de polinização cruzada, além da baixa taxa de germinação. a micropropagação é uma alternativa para a multiplicação em massa de cultivares de alta qualidade em taxas mais rápidas que os procedimentos convencionais, embora a propagação de cultivares de anthurium possa ocorrer de maneira vantajosa através da produção de sementes por embriogênese somática. , o anthurium (anthurium andraeanum) é uma das mais importantes flores de corte dentre as plantas t opi ais e a d i a o ódite ag í ola ais importante, movimentando cerca de , milhões de dólares por ano, só no hawaí. nos últimos anos tornou-se comum também em taiwan. o cultivo e a produção têm aumentado progressivamente em todo o mundo. a qualidade e a quantidade de fertilizantes aplicados influenciam no crescimento, produção e qualidade das flores de corte do anthurium. contudo, o aumento da demanda por flores de corte envolve o aumento da aplicação de nutrientes e excesso de santos, a. p. b. rev. virtual quim. |vol | |no. | | - | fertilizantes, afetando o meio ambiente e a saúde humana. a utilização de fertilizantes orgânicos, provenientes de excreção animal ou resíduos agrícolas, passou a ser uma alternativa ambientalmente mais segura, sustentável e que promove o aumento das propriedades físicas, químicas e biológicas do solo através da adição de matéria orgânica. dentre as vantagens, pode-se observar o aumento da produção e das propriedades do solo incluindo a capacidade de retenção de água, porosidade, agregação estável da água e redução da densidade e encrostamento superficial do solo. estudos mostraram que fornecimento insuficiente de nitrogênio e potássio reduziu drasticamente o crescimento, a fase vegetativa e o rendimento de anthurium andraeanum, além de produzir flores de qualidade mais baixa. fertilizantes químicos e orgânicos melhoram o crescimento, o desenvolvimento, o rendimento e a qualidade das flores de corte de anthurium andraeanum. tratamento desta espécie com fertilizante orgânico prhc (fertilizante orgânico da casca da ervilha e do arroz) mostraram resultados semelhantes aos obtidos com fertilizantes químicos. o melhoramento de cultivares visando à resistência a doenças é uma característica desejável para a manutenção da produção de flores e diversas medidas de controle devem ser tomadas para prolongar essa resistência como, por exemplo, a remoção de restos do cultivar, a irrigação por gotejamento e a nutrição equilibrada. a doença bacteriana (ferrugem) causada pelo xanthomonas axonopodis pv. dieffenbachiae é formalmente conhecida como xanthomonas campestris pv. dieffenbachiae. esta é a doença mais devastadora do anthurium andraeanum. a doença foi descrita pela primeira vez na década de na ilha kauai – hawaí, e anos mais tarde na maior parte dos países produtores de antúrio. a doença é caracterizada pelo aparecimento de manchas escuras de halo amarelo, folhas e pecíolos amarelados que acarretam no rompimento das flores e posterior colapso da planta. medidas de controle químico e biológico contra a ferrugem têm sido pouco efetivo. embora, saneamento e medidas preventivas sejam eficientes, elas são difíceis e de elevados custos. a utilização da biogenética na produção de cultivares resistentes é uma alternativa eficiente, a fim de evitar os efeitos nocivos da infestação pela ferrugem. , no brasil, as doenças descritas para o anthurium são a podridão das raízes (phytophthora sp. ou pythium sp.), a antracnose (colletotrichum gloeosporioides), a podridão negra (phytophtora citrophthora), que afeta a parte aérea da planta, pestalotiopsis guepinii causando manchas necróticas em folhas e flores. dentre essas, destaca-se a antracnose por estar presente na maior parte dos cultivares brasileiros. nas folhas, os sintomas de antracnose compreendem lesões pardas que predominam nos bordos foliares ou junto às nervuras, podendo coalescer e afetar grande parte do limbo foliar. a incidência da doença aumenta quando as condições ambientais de umidade relativa e temperatura são favoráveis ao desenvolvimento do patógeno. nas espatas ocorrem pequenas manchas escuras, que evoluem para uma podridão encharcada. . o gênero caladium o gênero caladium é constituído por espécies e pertence a tribo caladieae. destas espécies, o caladium bicolor é a maior fonte de cultivares. conhecidas como tinhorão ou tajá, as espécies do gênero caladium são nativas da américa do sul, e encontradas nas regiões neotropicais do sul da américa central, norte da argentina e brasil. figura : caladium bicolor a caladium bicolor, espécie mais difundida como planta ornamental do gênero caladium, é uma planta geófita, facilmente reconhecida por apresentar lâmina foliar sagitada (forma de seta), peltada (pecíolo inserido no meio do limbo foliar), com variegação (zonas com diferentes cores) brancas e santos, a. p. b. rev. virtual quim. |vol | |no. | | - | vináceas. as espécies de caladium são cultivadas como plantas ornamentais, devido a beleza de suas folhagens encontradas nas mais variadas formas e cores. a maior parte dos cultivares é propagado a partir de tubérculos apesar de o processo poder ocorrer através de sementes. para atender ao mercado da floricultura, novos cultivares são desenvolvidos por hibridação com a finalidade de atender características como ambiente de crescimento, produção de tubérculo, força do pecíolo, resistência a doenças e pestes, e coloração da folhagem. as espécies deste gênero são divididas em dois g upos o he idos po fa leaf e st ap leaf disti guidos pelo fo ato da folha. a caladiu fa leaf ap ese ta u a folha em forma de coração e pe íolo aule e eto, e ua to ue a st ap leaf te folhas estreitas e lanceoladas (forma de lança) e pecíolo curto, produzindo uma planta mais compacta. apesar de a toxicidade das espécies do gênero caladium associada a presença de ráfides de oxalato de cálcio e de outros princípios ativos, a literatura descreve sua utilização como bioadsorvente de metais pesados como chumbo e cádmio de águas residuais. além disto, descreve também a utilização da caladium bicolor como aditivo no preparo do polímero ldpe, como alternativa para aumentar as suas propriedades mecânicas e biodegradantes. - figura . caladium bicolor . conclusão o número e a vasta distribuição das espécies da família araceae revela sua diversidade e ocorrência em todo o mundo. apesar destas espécies já serem objetos de estudo de alguns pesquisadores, pouco se sabe sobre a composição química e a sua toxicidade. agradecimentos os autores agradecem ao instituto de tecnologia em fármacos-farmanguinhos/fiocruz e a pós- graduação em química pelo apoio à pesquisa e à professora de língua portuguesa thaís helena moreira da silva por sua valiosa contribuição na correção desse manuscrito. referências bibliográficas sítio the cate project. disponível em: . acesso em: setembro . coelho, m. a. n.; waechter, j. l.; mayo, s. j. rodriguésia, , , . 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[crossref] http://mobot.org/gardeninghelp/image.asp?ima ge=bloom .jpg, acessado em julho de . http://dx.doi.org/ . /s - x - http://dx.doi.org/ . % fs - http://dx.doi.org/ . / - -m http://dx.doi.org/ . /s - - - http://dx.doi.org/ . /aob/mci http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /j. - . . .x http://dx.doi.org/ . /s - - http://dx.doi.org/ . /j.phytochem. . . http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /jxb/ern http://www.ncbi.nlm.nih.gov/pubmed/ http://mobot.org/gardeninghelp/plantfinder/plant.asp?code=b http://mobot.org/gardeninghelp/plantfinder/plant.asp?code=b http://rodriguesia.jbrj.gov.br/rodrig _ / _nadruz.pdf http://rodriguesia.jbrj.gov.br/rodrig _ / $ - $.pdf http://dx.doi.org/ . /s - http://dx.doi.org/ . /s - - http://dx.doi.org/ . /np http://www.ncbi.nlm.nih.gov/pubmed/ http://dx.doi.org/ . /ijmm_ http://dx.doi.org/ . /s - http://dx.doi.org/ . /s - - http://davesgarden.com/guides/pf/showimage/ / http://davesgarden.com/guides/pf/showimage/ / http://dx.doi.org/ . /a: http://dx.doi.org/ . /ivp http://dx.doi.org/ . % fj.scienta. . . http://dx.doi.org/ . /j.scienta. . . http://dx.doi.org/ . % fa% a http://dx.doi.org/ . /j.scienta. . . http://rodriguesia.jbrj.gov.br/rodrig _ / -id .pdf http://toptropicals.com/html/toptropicals/catalog/photo_db/c.htm?numperpage= &numperline= &listonly= &first= http://toptropicals.com/html/toptropicals/catalog/photo_db/c.htm?numperpage= &numperline= &listonly= &first= http://toptropicals.com/html/toptropicals/catalog/photo_db/c.htm?numperpage= &numperline= &listonly= &first= http://dx.doi.org/ . /anbo. . http://dx.doi.org/ . /vol -issue -fulltext- http://dx.doi.org/ . /vol -issue -fulltext- http://mobot.org/gardeninghelp/image.asp?image=bloom .jpg http://mobot.org/gardeninghelp/image.asp?image=bloom .jpg abstract resumo . introdução: a família araceae . o gênero dieffenbachia . o gênero colocasia . o gênero philodendron . o gênero anthurium . o gênero caladium . conclusão referências bibliográficas microsoft word - happinessbeauty .docx very preliminary december “beauty is the promise of happiness”*? jason abrevaya and daniel s. hamermesh** *stendhal (marie-henri beyle), de l’amour, ch. . **professor of economics, university of texas at austin; sue killam professor in the foundations of economics, university of texas at austin, and professor of labor economics, maastricht university, iza and nber. abstract we measure the impact of individuals’ looks on their life satisfaction or happiness. using four data sets, the quality of american life surveys from the s, the british national child development study, and the wisconsin longitudinal survey, we construct the beauty measures in different ways that allow putting a lower bound on the true effects of beauty. personal beauty raises happiness, with a one standard- deviation change in beauty generating about . standard deviations of additional satisfaction/happiness among men, . among women. accounting for covariates that might be affected by differences in beauty, particularly effects in the labor and marriage markets, these impacts are at least halved. at least the majority of the effect of beauty is through economic outcomes, broadly defined. i. introduction while economists have studied happiness for several generations (easterlin, ; scitovsky, ), it seems fair to say that our interest in it has burgeoned in the last years. the frey and stutzer ( ) survey captured part of the literature, but there has been a continuing outpouring of research on happiness from an economic viewpoint (e.g., clark et al, ; stevenson and wolfers, ; deaton and kahneman, ; oswald and wu, ). much of the analysis focuses on measuring the short- and long-run effects of changes in income on happiness, but the relation of happiness to other outcomes that are at least partly economically determined (divorce, fertility and others) has also been subject to discussion. at the same time a smaller, but also burgeoning literature on the effects of beauty on various outcomes has been created (e.g., hamermesh and biddle, , möbius and rosenblat, , mocan and tekin, ). in these studies the economic focus is on such topics as how beauty is traded for income, how it alters occupational choice, and how it affects marital bargaining. the general issue is how human beauty determines outcomes in various markets and shifts the distribution of surpluses in those markets among participants. economists have not put these two topics together—have not examined the relationship between happiness and beauty. some psychologists have correlated subjects’ happiness and their self-assessed beauty, but that approach seems flawed. others have examined simple averages of several measures of happiness among a random sample of people whose beauty was rated differently by interviewers (using one of the data sets we use, umberson and hughes, ), of college students whose photographs and happiness were examined (diener et al, ), and of partial correlations of happiness measures and survey respondents’ waist-to-hip ratio, used as a (to us quite unsatisfactory) proxy for beauty (plaut et al, ). here we put the two literatures together, examining how happiness, measured in various ways, is affected by beauty and, as important, measuring the extent to which any effects of beauty on happiness occur indirectly through its effects in labor, marriage and other markets. we need to be as certain as possible that our analysis does not merely reflect the idiosyncrasies of measuring the subjective concepts of happiness and human beauty. for that reason we use four different surveys, representing three different approaches to measuring human beauty. all four surveys offer different measures of life satisfaction or happiness. happiness is obviously self-rated by the respondents, but none of the beauty measures is—we are not relating a person’s subjective assessment of one aspect of life to his/her assessment of another (hamermesh, ). our results’ validity will depend on their robustness to differing approaches to measuring beauty and to eliciting people’s expressions of satisfaction/happiness. ii. data sources and descriptive statistics the four data sets that we use are especially diverse in terms of their methods of assessing beauty. the first two are the quality of american life (qal) surveys, undertaken in and as random samples of the u.s. population, with the purpose of obtaining information on respondents’ subjective views of a large variety of aspects of life. at the end of the interview in each of these surveys, the interviewer assessed the interviewee’s looks on a five-to-one scale, with being strikingly handsome or beautiful, being homely. the complete list of descriptions associated with each rating of beauty is shown in the first column of the first panel of table . this measure has been used in a variety of studies linking beauty to economic outcomes (e.g., hamermesh and biddle, ; leigh and susilo, ), although typically with the top two categories combined into a category “good looks” and the bottom two combined into “bad looks,” because of the paucity of respondents rated or . in all of the analyses we use whatever measures of satisfaction/happiness are available. the analyses are thus data-driven, so that we are not inquiring into the various aspects of satisfaction/happiness that have been identified by psychologists (e.g., seligman, ). thus the qal surveys provide the same measures of happiness, each on a three-to-one scale, as the description in column ( ) of table shows. the surveys also provide direct measures of life satisfaction, focused on the current moment and on the person’s total experience, measures that are standard in the life satisfaction literature. henceforth we distinguish in these data sets and one of the others between the determinants of life satisfaction and those of happiness. one might argue that beauty, assessed as it is at the same time that the respondent’s happiness/life satisfaction is elicited, might be reflecting reverse causation. as one observer noted, “there is no cosmetic for beauty like happiness.” perhaps the interviewer reacts more positively to people who are happier/more satisfied and thus rates their beauty more highly. this reflection of happiness in assessed beauty could stem from the person’s overall demeanor, from his/her smiling more, or from some other specific cause. regardless of its source, however, this possible reverse causation necessitates using other sets of data, with other methods of assessing beauty, to replicate our results. another american data set with measures of both beauty and happiness is the wisconsin longitudinal survey (wls), a study of a cohort of high-school graduates from . the graduation pictures of the participants were assessed in by panels of raters, nearly all of whom were born earlier than the respondents, and who thus had a feel for what was viewed as good or bad looks in the late s. each respondent’s picture was rated by individuals ( men and women), with raters’ ages ranging between and (in ). the ratings were normalized within a given rater (de- meaning and dividing by the standard deviation) and averaged over raters. wls respondents were interviewed in and (at ages and ) and asked questions about their general feelings in recent days. in particular, each was asked how many days last week s/he was happy, how many days s/he enjoyed life, and how many days s/he was sad. these happiness measures were thus obtained and years after the photographs from which the respondents’ beauty was rated were taken. since a lot of time has elapsed between the beauty rating marguerite power farmer gardiner, countess of blessington ( – ). and happiness assessments, measurement error in beauty (as a proxy for current beauty) could be a concern. the fourth data set is the british national child development study (ncds), a longitudinal examination of britons born march - , . at age , and again at age , each student’s teacher assessed his/her attractiveness, along a scale shown in column ( ) of table . we aggregated these into the three categories, good-looking, average-looking and unattractive, similar to previous work relating these ratings to subsequent earnings (harper, ). in various later waves of the survey, including , , and (ages , , and ), the remaining respondents were asked questions designed to elicit their happiness or life satisfaction, some which have been studied before using these data (e.g., blanchflower and oswald, ). in the three most recent waves life satisfaction was elicited in a question (column ( ) of table ) focusing on the respondent’s entire life experience. happiness at age was also measured in a backward-looking manner, while happiness at age was measured with reference to the respondent’s current situation only. being assessed even earlier than those in the wls, these beauty measures arguably suffer from more measurement error as proxies for beauty in adulthood. potentially far more serious is that they are based on assessments by teachers, who presumably knew the students well and are unlikely to be unbiased assessors of their student’s attractiveness. any highly autocorrelated unobservable effect—ability, drive, etc.—is likely to be positively correlated with the assessment of beauty. whether this positive bias to the estimated effect of this beauty measure on happiness is greater or smaller than the attenuation bias due to classical measurement error is unclear; but for our purposes these data have at least as great difficulties as those in the qal surveys. in tables a- c we present descriptive statistics for the qal surveys, the wls and the ncds respectively. consider first the qal. as is usual in assessing beauty, more people are rated other studies have assessed beauty from school pictures taken nearly two decades before the outcome to which the assessments were linked (biddle and hamermesh, ), and one study even showed a high correlation between the assessments of pictures of -year-olds and those of the same individuals taken at age (hatfield and sprecher, , p. ). in the top two categories than in the bottom two; and the majority are rated as average-looking. also as is usual, women are rated more extremely than men (hamermesh, , chapter ). consistent with the previous satisfaction/happiness literature, most people are fairly happy and satisfied. there is no consistent gender difference in average satisfaction/happiness. because the beauty measures in the wls were normed, we do not list them in table b. in these data people report being happy on most days (on average, between and days) in the week before the survey. the number of days reported as being sad is typically percent or less than the number of happy days. with one exception—number of days reported happy in the wave of the survey—female respondents are less happy than males. table c shows that, as in the qal data, in the ncds females’ looks (in this case at age ) were rated more extremely than males’. perhaps, however, because of their close acquaintance with their charges, the teachers who rated the students’ attractiveness included more students in the attractive (good-looking) category than in the excluded category (presumably children viewed as neither attractive nor unattractive). most of the respondents were fairly happy or satisfied at ages - ; but, unlike in the wls, in three of the five cases women were significantly happier/more satisfied than men. before discussing our main regression results, we provide a brief theoretical discussion regarding concerns about measurement and endogeneity problems with the beauty ratings that we use. to focus only on the beauty rating, consider the following simple linear regression model, with (satisfaction/happiness) as the dependent variable and true (latent) beauty ∗ as the explanatory variable: ∗ , , . we assume homoskedasticity throughout this section and therefore omit conditioning on ∗ to simplify notation. the subscript t indicates the time at which the happiness measure is observed. ∗ is a measure of beauty that would be obtained by a person who had no contact with the subject but evaluated his/her beauty at the same time the subject’s satisfaction/happiness was measured. we consider three possible sources of difficulty in measuring beauty: ( ) measurement error in the beauty rating: the beauty rating used in the actual regression is an imperfect measure of ∗, even if it is obtained at the same time t as the happiness measure. ( ) depreciating accuracy in the beauty rating: since beauty changes, albeit slowly, over time, the inherent noise in the beauty rating will be larger the more that the rating pre-dates the satisfaction/happiness measure. the variance will be an increasing function of the time interval between observation of the beauty rating and observation of the happiness measure, a problem in both the ncds and the wls. ( ) bias in the beauty rating: if the beauty rating is elicited after the rater has spent time interacting with the subject (e.g., in an interview, as in the qal, or as a teacher, as in the ncds), we would expect a positive correlation between the beauty rating and the unobservable component of the happiness outcome. for instance, an interviewer might have a better opinion of a subject’s beauty if the subject projects self- confidence in the interview, which might occur if the subject is happier. the following stylized model for the observed beauty rating incorporates each of these three possible sources of difficulty: ∗ , where is the time at which the beauty rating is obtained. the depreciation component of the measurement error is , which has a variance that is linear in the time interval : , , . the other component of the error, denoted , is similar to a classical measurement error, except that we also allow it to be correlated with the happiness residual : , , , , . for this general model, the inconsistency of the least-squares estimator is given by the probability limit of the slope estimate: , ∗ , ∗ ∗ ∗ ∗ , where ∗ denotes the variance of ∗. (note that the textbook case of classical-measurement error is a special case of this formula corresponding to (no rating bias) and (no depreciation effect), for which ∗ ∗ .) for the qal datasets, the beauty rating is provided by the interviewer at the same time that the satisfaction/happiness measures are elicited. there is no depreciation effect since , but the interview format leads to the possibility of a bias in the beauty rating ( . the probability limit of the slope-estimate in this case simplifies to ∗ ∗ . if is positive, the usual attenuation inconsistency associated with classical measurement error is offset by the inconsistency associated with the beauty-rating bias. the overall direction of the inconsistency depends on whether (upward inconsistency) or (downward inconsistency). for the wls dataset, the beauty rating is based upon a subject’s high-school picture and the happiness measure is elicited during adulthood. a depreciation effect would be expected, since , and the lack of interaction between the rater and the subject eliminates concerns about beauty- rating bias. entering into the general formula yields: ∗ ∗ . attenuation inconsistency is expected here due to the mis-measurement and depreciation. the estimated beauty slope from the wls regressions should therefore be considered as “too low” (a lower bound to the true effect). finally, for the ncds dataset, all three difficulties could arise, since the beauty ratings were assessed in childhood ( ) by teachers who were very familiar with the subjects ( ). as a result, the general probability-limit formula in ( ) would apply. as with the qal data, the beauty- rating bias acts in an opposite direction from the measurement error. the impact of measurement error here, however, would be expected to be much larger than in the qal, since the beauty ratings in the ncds are assessed decades before the expression of happiness is elicited (as captured by . although it is difficult to say how the values of would compare between the qal and ncds, the large difference in the variance of measurement error between the two studies leads us to believe that the probability limit for the ncds estimates would be lower than that for the qal estimates. iii. basic results in this section we use ols to estimate linear models relating life satisfaction/happiness to beauty in each of the four data sets. for each we first include as regressors only the beauty measure(s) and, in the qal, the few covariates that cannot be caused by differences in beauty; then we add a number of covariates that have been shown to affect happiness but may not mediate the effect of beauty on satisfaction/happiness. in the next section we report on a large number of robustness checks that include varieties of additional controls, alternative beauty measures and more complex estimation procedures. table a presents the estimates based on the two qal surveys. among women all the coefficients have the expected signs—positive on the indicator for good looks (above-average or beautiful—the upper third of looks), negative on the indicator for bad looks (below-average or homely—the bottom eighth of looks). this is true whether or not we control for age, education, race, number of children and marital status. indeed, the addition of the vector of controls hardly alters the point estimates of the coefficients among women; and nearly all the estimates are statistically significantly different from zero. among men almost all of the point estimates have the expected sign, and they are generally statistically significant in the data. as with women, adding the vector of controls does not greatly alter the point estimates. the effects of differences in beauty on life satisfaction or happiness are not small, at least in the data. using the estimates from the equations expanded to include controls, going from the bottom eighth of women’s (men’s) looks (those rated below-average) to the top third (those rated above-average) raises satisfaction with life by . ( . ) standard deviations; the effects on happiness of this difference in beauty are . ( . ) standard deviations. the impacts of differences in beauty in the data are smaller, but still average about . standard deviations. the results based on the wls, with number of days happy, enjoyed and/or sad, are presented for the respondents observed at ages and in table b. the upper part of the table contains only the unit-normal measure of beauty, while the bottom part adds years of education, marital status, number of children, bmi observed at high-school graduation, and current bmi. these latter two, which were unavailable in the qal surveys, allow for possible correlations between ratings of attractiveness and overweight/obesity (although the evidence for the labor market suggests that the correlations, and their impacts on wages, do not affect the estimated effects of beauty on whether we should be controlling for marital status here is unclear. there is substantial evidence that married people are happier (e.g., blanchflower and oswald, ; oswald and wu, ); but one’s gains from marriage are affected by one’s looks (hamermesh and biddle, ). in both of these data sets, however, there are only small differences in marital status by looks: holding age and gender constant, being above-average in looks has no effect on marital status compared to being average-looking, while being below-average in looks has a marginally significant negative impact on the probability of being married. outcomes—hamermesh and biddle, ). as with the results for the qal, adding this vector of covariates hardly alters the estimated impacts of attractiveness on the measures of satisfaction/happiness. there is no significant impact of attractiveness on happiness among men at either of the two ages at which these adults are observed. among women, however, in all the estimated equations the more attractive respondents are significantly happier at age than less attractive respondents. the impacts are smaller relative to the standard deviations of satisfaction/happiness than in the qal (see below), an unsurprising result of the likelihood of the differences in the nature of the measurement errors in the two samples. we can explain the disappearance of the results for women as they age by the possibility that the correlation of attractiveness at age with attractiveness at age may be greater than that with attractiveness at age . the absence of any relation between attractiveness and happiness among men is harder to explain, especially in light of the fact that labor-market effects are at least as large among men as among women. one possibility is that there is inherently more measurement error in the ratings (assigned over years after the pictures were taken) of men’s high-school graduation pictures than of women’s, a possibility we examine indirectly in the next section. table c shows the results of relating measures of happiness and satisfaction in adulthood in the ncds sample to attractiveness as assessed by a child’s teacher at age . the first part of the table includes only indicators for being rated as attractive or as unattractive (with a middle category excluded). all of the estimated impacts that are statistically significant are of the expected sign, and there is no obvious difference in the size or significance of the effects between men and women. the second part of table c reports the estimates of the impacts of the beauty indicators when indicators for educational attainment, marital status, number of children, bmi at age and current bmi are added to the equations. the estimated effects of attractiveness are typically somewhat attenuated when the control variables are added, although the overall conclusions remain the same: where significantly nonzero, the beauty measures have the expected effects; and, as in the upper part of the table, the impacts of beauty are roughly the same by gender. there is a welter of estimates here— coefficient estimates for each gender, based on four different samples. among men in all four samples taken together, only of the have the “incorrect” sign; and of the “correctly” signed, are statistically significantly nonzero. among women of the estimated effects are incorrectly signed (and not significantly nonzero), but are correctly signed and statistically different from zero. while these comparisons clearly suggest a positive answer to the titular question of this study, we would like to compare the estimates across the samples, given the differences in the potential biases to our estimates across the samples. to do so we calculate the effect of being at different percentiles of the distribution of beauty on the level of satisfaction/happiness measured in standard deviations. thus, for example, we assume that the average male among the . percent rated as below-average in the qal is at the th percentile of the distribution of looks and is thus . standard deviations below the mean beauty of men. we use this type of approximation for all the qal and ncds results, and for the wls (where the beauty rating was a unit normal deviate) we impute as percentiles of the distributions the simple averages of the imputed percentiles in the other surveys. the results of these calculations are shown in figures a and b, with each of the points in a figure representing the fractional change in standard deviations of satisfaction/happiness generated by a movement from the mean beauty to some point in the distribution below or above the mean. among men (women) the average good-looking respondent is . ( . ) standard deviations above the mean of beauty, while the average bad-looking respondent is . ( . ) standard the categories represented by the vector of education indicators are: cse or equivalent, o-level or equivalent, a-level or equivalent, higher qualification, or university degree or higher, with no qualification the excluded category. deviations below the mean. on average, among men (women) the gain from being this good-looking is . ( . ) standard deviations along the satisfaction/happiness index compared to the average male (female), while the loss from being this bad-looking is . ( . ) standard deviations of satisfaction/happiness. assuming, as these calculations must, that the effects are linear within the categories above-average and average, or attractive and unattractive, the results in the expanded specifications imply that a one standard-deviation increase in beauty raises satisfaction/happiness by . ( . ). this is not large, far smaller than the impact of income on happiness in a cross-section (computed from frey and stutzer, , table ), although that calculation is based on decile averages rather than individual observations. the effect is about the same magnitude as has been reported in other literatures dealing with related subjects (e.g., carrell et al, , on educational production functions). the relative sizes of the estimates accord with the discussion in section ii of measurement error. they are largest in the regressions based on the qal, where we expected the simultaneous assessment of beauty and happiness to generate positively correlated measurement errors. they are smallest, and certainly negatively biased, in the estimates based on the wls, where changes in beauty will have led to classical measurement error that has grown over time. as in the qal the direction of the bias in the estimates based on the ncds is unclear, since the errors induce opposite- signed biases, but as expected the estimates are generally below those from the qal. overall the estimates from the four sets of data suggest the following tentative conclusions: . there is a positive effect of good looks on satisfaction or happiness, and a negative effect of bad looks, even accounting for a variety of demographic variables that might be correlated with beauty and/or satisfaction/happiness. . these effects are not huge, but the true impacts are certainly larger than those implied by the wls results. . the impacts of beauty or its absence on satisfaction/happiness generally seem slightly larger among women than among men, and the estimated effects are more reliable among women. iv. robustness checks and methodological extensions in the previous section we attempted to place a lower bound on the estimated impacts of beauty on happiness. in none of the estimation, however, were we concerned about alternative measures and specifications, nor did we consider alternative approaches to estimation. we do that here, in each case basing the estimates on the expanded specifications with control variables (specification ) in tables a-c. a. re-specifying proxies for beauty and considering confounding variables no sensible reformulations of the beauty ratings in the qal survey can be done to check their robustness; but we can use alternative measures in the wls and ncds. in the former we re- estimated the expanded specifications using first the normalized beauty ratings given by female raters to pictures of female respondents, and by male raters to male subjects. we then switched and re-estimated the equations using opposite-sex ratings. most of the estimates are attenuated slightly, just as expected assuming that there is more measurement error in these assessments of beauty when fewer raters are used; but all of those that were statistically significant (women in ) remain so. the ncds respondents’ appearance was assessed by their teachers at age as well as by their teachers at age (the measures used in section iii). to the extent that the measurement error in the variable we used arose from random errors in an individual teacher’s assessment of the child’s appearance, averaging the teachers’ ratings at ages and will reduce that error. accordingly, we average the indicator variables for appearance at with identically defined variables describing appearance at age . these average measures replace the age- measures in the estimating equations, and the age- bmi is replaced with the average of bmi at ages and . in a few cases some previously insignificant parameter estimates in table b become marginally significant, but in the qal , for example, only of the respondents are rated as strikingly handsome or beautiful, and only are rated as homely. when we re-estimated the models with measures encompassing each of the five beauty ratings, unsurprisingly, given the cell sizes at the extremes, this extension hardly altered the conclusions. otherwise there is no change. implicitly, whatever measurement errors exist in the age- proxies are highly positively correlated with those in the age- data and thus cannot be eliminated by averaging. another concern is that different assessors rate beauty differently, and that their idiosyncrasies may be correlated with the subjects’ happiness. with each teacher in the ncds assessing only one subject’s appearance this issue cannot be examined in those data; and we cannot identify the raters in the wls. in the qal surveys, however, we know which raters assessed each subject’s beauty. accordingly, we re-estimate the equations in the bottom half of table a adding interviewer fixed effects. with one exception (the impact of bad looks among women in the data) none of the significant impacts shown in table a became statistically insignificant, nor did any of the estimated effects of looks on happiness reverse sign. the vectors of interviewer fixed effects were themselves always statistically significantly nonzero—some raters were consistently more generous than others—but their addition hardly altered the estimated effects of beauty on happiness. another potential difficulty with the results is that there are location-specific determinants of beauty that may also directly affect people’s perceived satisfaction/happiness. for example, perhaps living in los angeles with its proximity to mountains and ocean makes people happier and also attracts good-looking people. in the two data sets that contain longitudinal data there is strong evidence, consistent with gautier et al ( ), that changes in location are related to beauty. to we also used the age- measures alone—looks and bmi—in place of the age- measures. perhaps unsurprisingly, the results were slightly weaker than with the age- measures, and thus somewhat weaker still than the specifications based on the age- and age- averages. for example, in the wls we can compare the beauty of the wisconsin high-school graduates who remained in the state to those who were not living there at age . the average beauty of those still residing in wisconsin at age was . (s.e.= . ), while the beauty of those who had left was . (s.e.= . ). those who remained are significantly worse-looking than those who left. because the ncds was national, it allows us to compare the beauty of those who entered, those who stayed and those who left an area. because the definitions of the british regions were not the same in all the ncds waves, we cannot examine mobility and beauty for all areas; but southeast england, and scotland and wales, are consistently identified at ages and . (since most geographic mobility in the sample occurs between these ages, this is the most useful single comparison.) . (s.e. = . ) of those who moved to the southeast investigate this issue in the qal surveys, we add state fixed effects to the basic equations in table a. as in the other re-specifications in the qal, this extension hardly altered the results. although the vector of state effects was itself statistically significant, and its inclusion did increase slightly the absolute values of the estimated effects of the beauty indicators, there were no qualitative changes in their impacts. in the wls the only locational information is whether the wisconsin high-school graduate still resides in the state at the time of the interview. adding this location variable to the specifications for the three outcomes in table b produces only minute changes in the estimated impacts of beauty. no signs change, and the impacts remain statistically significant only for women observed in . in the ncds we can account for regional effects in both the assessments of beauty during childhood and the effect of childhood beauty on adult happiness. there may be regional differences in beauty standards, which using region in childhood as a control would account for; and there may be regional differences in the relationship between beauty and satisfaction/happiness, which using location as an adult could account for. we thus re-specify the equations in table c to include vectors of regional indicators at age and at the time the respondent’s happiness/satisfaction is reported. in no case did either of these vectors of fixed effects approach statistical significance; nor did their inclusion qualitatively alter the impacts of beauty on satisfaction/happiness. in these data, at least, regional differences in childhood and adulthood just are not important in affecting the estimated relationships between beauty and satisfaction/happiness. were good-looking at age , but only . (s.e. = . ) of those who stayed were, and only . (s.e.= . ) of those who left were good-looking. the southeast attracted good-looking people, while less good- looking people moved elsewhere in the u.k. while not statistically significant, the differences in scotland and wales are exactly opposite those in the southeast: . (s.e.= . ) of those who entered were good- looking; . (s.e.= . ) of those who stayed were; and . (s.e.= . ) of those who left were. the small samples of entrants and leavers mean these differences are not statistically significant; but the differences in the fractions considered bad-looking are: . (s.e.= . ) among entrants, . (s.e.= . ), and . (s.e= . ) among leavers. before examining additional covariates that we have ignored, consider a conundrum in the wls results: the effects of beauty on happiness are apparent (in table b) in (at age ) but not in (at age ). one reason might be that beauty effects on happiness generally diminish as one advances past middle age. to explore this possibility the only way that these data sets allow, we re-estimate the second specifications in table a for the qal surveys, adding interactions of the quadratic in age with the variables measuring beauty assessments. while in about half of the eight re-specified equations the additional four variables were jointly significant (at the -percent level), the effects of beauty on happiness did not vary systematically with age in these equations taken together. another possibility is that the nearly -percent sample attrition in the wls between and changed the structure of the beauty-satisfaction/happiness relationships in the sample. re- estimating the models for with only those respondents who remained in the sample in generated the same significant results for women as were reported in table b. excluding these two explanations suggests either that the measurement errors resulting from using beauty assessed at age become increasingly important after middle age, or that some other, unknown effect generates the disappearance of the beauty effects on women’s happiness. an important determinant of happiness in other studies (see stevenson and wolfers, , blanchflower and oswald, ) has been health status. the difficulty here is that in all the data sets the measures of health are subjective, self-assessed, so that they are very likely to be determined by the same factors that determine happiness/satisfaction. nonetheless, we add self-reported health to the second specifications in each data set. in the qal surveys subjective health is based on the response to a question about whether the respondent has health problems (with about percent responding yes). an indicator of this subjective response in the specifications is strongly positively correlated with the happiness and satisfaction measures, as it is in the extensions of the wls and ncds results below. the estimated impacts of above-average and below-average looks on these outcomes, however, change only slightly, with only small decreases in their statistical significance and no changes in their signs. the wls contains self-rated health measures on the five-point scale, and we create an indicator for good health at the time of the interview comparing those whose self-rated health is excellent or very good to those whose self-rated health is good, fair or poor. between and percent of the respondents are classified as being in good health using this indicator. adding it to each of the specifications again has only small effects on the estimates and their significance. in the ncds subjective health was rated on a four-point scale—excellent, good, fair or poor—at ages and ; on a five-point scale (adding very poor) at age , and on a -point scale at age . we have created an indicator—good health—typically equaling if the individual reports being in excellent or good health, otherwise (with good health coded for , , and percent of the respondents at ages , , and respectively). in some of the equations for men the estimated effects of beauty on satisfaction/happiness are attenuated by the addition of subjective health status to the specification, although there are essentially no changes in the estimated effects in the equations among women. given the subjective, jointly reported nature of satisfaction/happiness and health status, the changes in the parameters we are focusing on seem fairly minor. a final check includes additional covariates related to the respondent’s siblings or parents. for some of wls respondents the survey obtained measures of their sibling’s happiness as well as their own. to the extent that there are family background effects in happiness (hartog and oosterbeek, ), including these measures could help isolate the effect of beauty independent of any correlation it might have with unmeasured characteristics in the respondent’s family background. own beauty is positively correlated with siblings’ beauty, so that adding sibling happiness to the specifications might be expected to have made the estimated effects of own beauty on happiness more negative. the wls provides measures of siblings’ happiness for about half of the respondents. adding these to the specifications nearly doubles the absolute magnitudes of the beauty impacts on happiness at age (and has little effect in the data). this appears due to sample selection: the same large effects are produced when we re-estimate the basic equation only over those respondents on whose siblings’ happiness information was available. we thus cannot distinguish whether the surprising increase in the effects is due to unexpected correlations of background measures (including the unreported siblings’ beauty) with reported happiness, or simply to selection issues. in the ncds we know whether the respondent’s parents are alive at his/her age , and . since parental death has been shown to affect well-being, we thus form an indicator for these latter two waves equal to if a respondent’s parent died in the five years preceding the interview (which occurred for percent of the respondents at age and percent at age ). in each of the six equations describing satisfaction/happiness at ages and a parental death in the quinquennium does have a negative effect; unsurprisingly, given that there is no reason to expect that the assessment of beauty at age will be correlated with parental mortality three decades later, this additional variable leaves the estimated beauty effects essentially unchanged. b. methodological extensions all of the specifications reported in tables a- c were estimated by ols—although in most cases the expressions of satisfaction/happiness take only a small number of values. to examine whether a discrete-variable modeling approach would change the results, we re-estimate the models (except for satisfaction in the qal , where the questionnaire allowed a large range of discrete responses). except for the wls this means estimating ordered probits over these specifications; in the wls, since the measures are of numbers of days (ranging from to ), we re-estimated the a five-year retrospective may be too long to observe an effect on current happiness, but that is the hiatus that the data limits us to. the effects are not changed greatly in any of the data sets when all the additional variables are included at the same time. this is not surprising, as within each data set these additional variables are typically nearly orthogonal. model using a count-data method (poisson estimation). these various estimation methods yielded qualitatively very similar results to those reported in section iii, with significant effects remaining. in the wls data the respondents’ underlying happiness is measured in three ways—by the days s/he identifies as being happy, as sad, or as having been enjoyed in the past week. each of these measures can be viewed as proxying the respondent’s underlying mental state—each is a noisy measure of that. to remove some of the noise we first simply subtract days sad from days happy and re-estimate the specifications that were presented in the bottom half of table b. then, since we do not know what the appropriate weights on these particular expressions of happiness might be, we re- estimate these equations using the first eigenvector (first principal factor) to weight the three expressions of happiness—days happy, days sad and days enjoyed—and use this measure as the expression of happiness to be described by the independent variables we present these re-estimates in table . they do not add much to the basic results. whether we just subtract sad from happy days, or use information on all three responses by using a dependent variable which weights each using the first eigenvector, the implications are the same as before: among men the effects of beauty are positive but statistically insignificant; among women they are positive and highly significant in , insignificantly negative in . v. inferring the direct and indirect effects of beauty the economic question in this study deals with the extent to which the effect of beauty on satisfaction/happiness occurs through markets: how much of the effect is direct—with people who are otherwise identical in every respect being happier or more satisfied than their less good-looking peers? how much is due to the fact that beauty enhances one’s outcomes in various markets, including the labor and marriage markets? writing the simplest model with no covariates except those that could not be affected by beauty (age and race in the qal) as: the effect of a different personal endowment, height, on happiness was decomposed into these components by deaton and arora ( ), with the adjustment limited to accounting for the impact of height in the labor market. ∗ , we can interpret the estimate of β as the total effect of beauty on satisfaction/happiness if we add as many covariates as we have information—both those included in the expanded specifications in tables , self-reported health, and measures of earnings and spouse quality—we obtain: ′ ′ ∗ ′. we definte the direct effect of beauty on satisfaction/happiness as ′, and the indirect effect as ′. in the qal the only additional covariates included in the vector x are self-reported health and the available measures of individual income. no doubt this paucity of additional covariates will generate an additional upward bias in the direct effect beyond the possible overall bias that we already noted. in the ncds estimates for that age , and waves we add self-reported health and own and spouse/partner’s weekly earnings, while in the age wave we replace spouse/partner’s earnings with family income (as partner’s weekly earnings are unavailable). finally, in the wls estimates for each of the two years we add health status and variables measuring the respondent’s own income and the household income (thus presumably proxying the earnings of a spouse if one is present). rather than presenting the estimates of these expanded specifications, in table we simply list the average effects of going from the mean beauty to being good-looking or bad-looking, measured in standard-deviation units of satisfaction/happiness per standard deviation of beauty. (the statistics listed in table for specification are the averages of those shown in figures .) the results show that the direct effects (based on the estimates from specification ) are typically around half of the total effect (based on the estimates from specification ). while this further expansion of the estimates accounts for some of the indirect effects of beauty on satisfaction/happiness, the available data do not allow us to account for the impacts in other markets. as just one example, there is growing evidence that beauty generates beneficial outcomes in lending markets (hamermesh, , chapter ). moreover, our proxies for the outcomes in the labor and marriage markets that are affected by beauty are far from perfect. it thus seems fair to conclude that the direct effect of beauty is at most one-half of the total effect, and perhaps much less. the majority of the impact of beauty on satisfaction/happiness appears to be economic—through its effects on outcomes in various markets. vi. conclusions and extensions we have examined the relationship between people’s life satisfaction/happiness and their beauty. both are subjective, although in each of our four empirical examples the agent describing his/her satisfaction differs from the agent(s) describing his/her beauty. while the beauty measures introduce difficulties into the inference of the true effect of beauty on happiness, those difficulties, which differ across our data sets, do not result because we make the simple mistake of essentially relating happiness to a proxy for happiness. the difficulties with the beauty measures are more subtle in our context, but they allow us to put a lower bound on the magnitudes of the true impacts of beauty on happiness. the results suggest that a person’s beauty does increase his/her satisfaction/happiness. the effects may be larger among women than among men, but the differences by gender in the relationship are not great. among both men and women at least half of the increase in satisfaction/happiness generated by beauty is indirect, resulting because better-looking people achieve more desirable outcomes in the labor market (higher earnings) and the marriage market (higher-income spouses). overall our findings imply that much of the differences in happiness that exist in a society arise from characteristics that are completely beyond one’s control. substantial evidence (see hamermesh, , chapter ) makes it clear that even radical measures to alter one’s looks have fairly small effects. at least along the dimension of this one determinant of happiness, focusing on creating a happier society is not likely to be fruitful. references biddle, jeff, and daniel hamermesh, “beauty, productivity and discrimination: lawyers’ looks and lucre,” journal of labor economics, (january ): - . blanchflower, david, and andrew oswald, “well-being over time in britain and the usa,” journal of public economics, ( ): - . --------------------------, and ----------------------, “hypertension and happiness across nations,” journal of health economics, ( ): - . carrell, scott, and james west, “does professor quality matter? 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estimating the effect of candidate ballot photographs on election outcomes,” journal of economic psychology, (feb. ): - . mocan, h. naci, and erdal tekin, “ugly criminals,” review of economics and statistics, (feb. ): - . möbius, markus, and tanya rosenblat, “why beauty matters,” american economic review, (march ): - . oswald, andrew, and stephen wu, “well-being across america: evidence from a random sample of one million americans,” review of economics and statistics, , forthcoming . plaut, victoria, glenn adams and stephanie anderson, “does attractiveness buy happiness? ‘it depends on where you’re from,” personal relationships, ( ): - . scitovsky, tibor, the joyless economy. new york: oxford university press, . seligman, martin, authentic happiness. new york: free press, stevenson, betsey, and justin wolfers, “economic growth and subjective well-being: reassessing the easterlin paradox,” brookings papers on economic activity (spring ): - . umberson, debra, and michael hughes, “the impact of physical attractiveness on achievement and psychological well-being,” social psychology quarterly, (sept. ): - . table . descriptions of beauty, satisfaction and satisfaction measures, four data sets beauty measure satisfaction measure happiness qal -point rating by interviewer at end of interview: how satisfied are you with taking all things together, how strikingly handsome or beautiful your life as a whole these days? would you say things are these good-looking (above average for age and sex) ( to scale) days--would you say you're very average looks for age and sex happy, pretty happy or not too quite plain (below average for age and sex) happy these days? ( to scale) homely qal same as qal how satisfied are you with same as qal your life as a whole ? ( point scale) wls constructed from ratings on an -point scale, with age : on how many days during endpoints labeled as "not at all attractive" ( ) and the past week did you feel happy? "extremely attractive" ( ), based upon an individual's (sad?) (values through ) high-school yearbook photo (in ); each photo was rated by six men and six women, and the contructed age : same measure is an average of the z-scores across the raters beauty measure satisfaction measure happiness ncds teachers' ratings of the student's appearance at age : all things considered, age , and at age . which best describes the how happy are you? ( to scale) student? attractive; unattractive; looks underfed; abnormal feature; scruffy and dirty. "looks underfed age : how satisfied are you and "scruffy and dirty" were coded as missing, with the way your life has turned "attractive" as good-looking, "unattractive" and out so far? ( to scale, from "abnormal feature" as bad-looking, others as neither. completely satisfied to com- pletely dissatisfied) table a. descriptive statistics, qal and qal , all observations with beauty rating, satisfaction and happiness responses* men women men women good looking . . . . bad looking . . . . life satisfaction . . . . ( . ) ( . ) ( . ) ( . ) happiness . . . . ( . ) ( . ) ( . ) ( . ) n *sample averages are reported, with their standard errors for non-binary variables in parentheses. table b. descriptive statistics, wls, all observations with beauty rating, satisfaction and happiness responses men women # days happy . . . . ( . ) ( . ) ( . ) ( . ) # days enjoyed . . . . ( . ) ( . ) ( . ) ( . b) # days sad . . . . ( . ) ( . ) ( . ) ( . ) n *sample averages are reported, with their standard errors for non-binary variables in parentheses. table c. descriptive statistics, ncds, all observations with beauty rating men women attractive age . . unattractive age . . n men women men women age : age : happiness . . ( . ) ( . ) life satisfaction . . ( . ) ( . ) n men women men women age : age : happiness . . ( . ) ( . ) life satisfaction . . . . ( . ) ( . ) ( . ) ( . ) n *sample averages are reported, with their standard errors for non-binary variables in parentheses. table a. results from regressions of life satisfaction and happiness and beauty ratings, qal and * men women good looks bad looks good looks bad looks specification : ols, beauty, age quadratic, race, life satisfaction - . - . . - . ( . ) ( . ) ( . ) ( . ) happiness . - . . - . ( . ) ( . ) ( . ) ( . ) specification : lpm, beauty, age quadratic, race, life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) happiness . - . . - . ( . ) ( . ) ( . ) ( . ) specification : add age quadratic, education indicators race, number of children, married, life satisfaction - . - . . - . ( . ) ( . ) ( . ) ( . ) happiness . - . . - . ( . ) ( . ) ( . ) ( . ) specification : add age quadratic, education indicators race, number of children, married, life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) happiness . - . . - . ( . ) ( . ) ( . ) ( . ) *estimates that are significantly non-zero, one-sided -percent level, in bold. table b. regressions of days happy, enjoyed or sad on beauty rating, wls ages and men women specification : ols, beauty only # days happy - . . . - . ( . ) ( . ) ( . ) ( . ) # days enjoyed . . . . ( . ) ( . ) ( . ) ( . ) # days sad - . - . - . - . ( . ) ( . ) ( . ) ( . ) specification : add completed education, married, number of children, hs bmi, current bmi # days happy - . . . - . ( . ) ( . ) ( . ) ( . ) # days enjoyed . . . - . ( . ) ( . ) ( . ) ( . ) # days sad - . - . - . - . ( . ) ( . ) ( . ) ( . ) *estimates that are significantly non-zero, one-sided -percent level, in bold. table c. results from regressions of life satisfaction and happiness on beauty ratings, ncds ages , , and men women attractive unattractive attractive unattractive age age age age specification : ols, beauty only age happiness . - . . - . ( . ) ( . ) ( . ) ( . ) age life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) age life satisfaction . - . - . - . ( . ) ( . ) ( . ) ( . ) age life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) happiness . - . . - . ( . ) ( . ) ( . ) ( . ) table c, cont. men women attractive unattractive attractive unattractive age age age age specification : add education indicators, number of children bmi , bmi current, married/partnered age happiness . - . . - . ( . ) ( . ) ( . ) ( . ) age life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) age life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) age life satisfaction . - . . - . ( . ) ( . ) ( . ) ( . ) happiness . - . . . ( . ) ( . ) ( . ) ( . ) *estimates that are significantly non-zero, one-sided -percent level, in bold. table . combining the impacts on days happy and day sad, wls ages and * men women # days happy - . . . - . # days sad ( . ) ( . ) ( . ) ( . ) first eigenvector . . . - . of # days happy, ( . ) ( . ) ( . ) ( . ) sad and enjoyed** *includes the additional regressors described in table b. **in the factor loadings are . , - . and . on days happy, sad and enjoyed. in they are . , - . and . . estimates that are significantly non-zero, one-sided -percent level, in bold. table . average effects of beauty on happiness/satisfaction, sdoutcome/sdlooks good looks bad looks men sd difference from mean . - . specification no. . (total effect) . - . . . - . . (indirect effect) . - . women sd difference from mean . - . specification no. . (total effect) . - . . . - . . (indirect effect) . - . figure a. effects of beauty on happiness/satisfaction, men, all data sets ‐ . ‐ . ‐ . ‐ . . . . . . ‐ . ‐ . ‐ . ‐ . . . . . . s td e v (h a p p in e ss / s a ti sf a ct io n ) stdev(beauty) qal ncds wls figure b. effects of beauty on happiness/satisfaction, women, all data sets ‐ . ‐ . ‐ . ‐ . . . . . . ‐ . ‐ . ‐ . ‐ . . . . . . s td e v (h a p p in e ss / s a ti sf a ct io n ) stdev(beauty) qal ncds wls environmental values ( ): – . © the white horse press doi: reconsidering scenic beauty arnold berleant professor emeritus of philosophy long island university email: ab@contempaesthetics.org abstract attempts to justify the objectivity and universality of aesthetic judgment have traditionally rested on unsupported assumptions or mere assertion. this paper offers a fresh consideration of the problem of judgments of taste. it suggests that the problem of securing universal agreement is false and therefore insoluble, since it imposes an inappropriate logical criterion on the extent of agreement, which is irrevocably empirical. the variability of judgments of taste actually forms a subject ripe for inquiry by sociologists, psychologists, historians and anthropologists, as well as by aestheticians. scenic beauty provides a vivid test for the variability of these judgments. keywords agreement, judgments of taste, universality, variability arnold berleant environmental values . i. the problem judging scenic beauty raises problems for aesthetics that aestheticians have long faced nobly but by which they have been ignobly defeated. this can, in fact, stand as a representative case for problems concerning judgments of taste en tout. it is often assumed that judgments of taste rest on the ob- jectivity of aesthetic value and that ideally these judgments should exhibit universal agreement. the fact that such agreement has never been reached seems not to have deterred philosophers from claiming that it is necessary in order for any such judgment to be valid. i want to propose that, on the contrary, judgments of taste are not only not universal but that universal- ity is neither necessary nor desirable, for it unduly constrains the range of aesthetic judgment. scenic beauty offers an attractive entrée into this problem, for its ap- preciation is widespread. delight in the beauty of landscape cuts across educational, cultural and intellectual differences and at the same time exhibits a high degree of concurrence. granted there have been historical differences in the appreciation of natural scenery, especially in the case of mountains and forests, once considered ominous and threatening and more recently majestic and noble. and the same transformation of taste seems now to be happening in the appreciation of swamp, marsh and desert land- scapes. although at various times common agreement has been widespread, universality remains elusive. the attempt to justify the objectivity and universality of judgments of scenic beauty rests on the conviction that such judgments of taste require universal agreement. this desideratum has not been borne out by empirical studies of landscape preference but it nevertheless remains the normative ideal. i would like to examine this issue afresh, not by appealing to em- pirical research on landscapes preference, which requires its own critical appraisal, but by reconsidering the philosophical issue. i want to propose that the requirement of universality is ungrounded and that it engenders a philosophical problem that is false and therefore insoluble. what remains for philosophic consideration are matters of a different kind that are more tractable and lead to a different kind of resolution. the question at issue concerns the range of normative judgments that different individuals make of natural beauty or of art. the object of appre- ciation is presumably the same for everyone, yet the value put on it is never unanimous but varies for different individuals and may even change for the same individual on different occasions. regardless of where the locus of beauty is considered to be, whether a property of the object or a sentiment reconsidering scenic beauty environmental values . in the subject, conventional logic carries the presumptions of objectivity and universality, and insists that judgments of the same object should agree. the reasons for this insistence vary. sometimes they rely on the claim that value is objective and that, if we recognise and identify it properly, our judgments would concur. often they rest on the belief that humans are basically similar and have similar capacities for aesthetic appreciation, and since our appreciation is directed toward the same object, our judgments may be expected to agree. the expectation, then, is of common agreement, yet the facts are oth- erwise and the problem lies in this disparity. both hume and kant faced this issue and their answers, though different, show remarkable similari- ties. let me start by recalling these classic accounts, not to critique them as representative models, but because they are useful in locating the salient features of the issue. hume’s discussion of the judgment of taste is widely regarded as defini- tive. briefly stated, hume distinguished between judgment and sentiment. sentiment, he recognised, is never wrong since it refers only to itself. if viewing a landscape from a hilltop gives us a thrill of pleasure, the pleasure is real and incontrovertible. if our companion is bored and would rather return to the tour bus and view the landscape on the tv monitor, that feeling is equally genuine. as hume put it, ‘all sentiment is right; because sentiment has a reference to nothing beyond itself, and is always real, wherever a man is conscious of it.’ it is different, however, if we ascribe beauty to the landscape, for then we are referring not to our feelings but to some thing beyond, and our judgment must conform to that object. ‘among a thousand different opinions which different men may entertain of the same subject, there is one, and but one that is just and true: the only difficulty is to fix and ascertain it. on the contrary, a thousand different sentiments, excited by the same object, are all right; because no sentiment represents what is really in the object.’ by opinion hume meant statements of fact, and for him, beauty does not lie in the object but rests only on our sentiment. however, there are qualities in objects that excite that sentiment, and the competent critic can identify and evaluate those qualities. it may be sufficient to say that the judgment of a critic who has keen sensibilities, wide aesthetic experience, and relevant knowledge is the most trustworthy, and that the judgments of such critics are likely to agree. nonetheless, according to hume, differences will result from ‘the different humours of particular men’ and ‘the particular manners and opinions of our age and country’. however, ‘[t]he general principles of taste are uniform in human nature’. hume thus leaves us with the possibility of widespread arnold berleant environmental values . agreement but at the same time with the recognition that residual differences are unavoidable but explainable. kant’s dissatisfaction with hume is well known, and he offered an alter- native that provided a more affirmative answer to the question of establish- ing agreement in aesthetic judgment. for kant the judgment of taste is not cognitive but aesthetic, and this means that it cannot avoid being subjective. like hume he believed that such judgments may refer to an object but that they rest on pleasure or pain, which signifies nothing in the object but only the feeling that the object evokes in the subject. kant nevertheless attempted to justify judgments that, though subjective, are universal, and he did this mainly by appealing to a common sensibil- ity, a sensus communis. while such judgments cannot be cognitive, their universality may nevertheless be claimed on the basis of this sensus com- munis. this, he thought, allows for what he called a ‘subjective universal’. but while there may be some feelings and responses toward the same object felt by most people, the extent to which that is so in individual cases is an empirical question and true universality is impossible to attain. what kant was left with, then, and all that was possible, was the claim of universality of a sort, ‘subjective universality’. despite their radical differences, both hume and kant shared some key ideas. neither claimed cognitive universality for judgments of taste. hume seemed to think that universality was theoretically possible since judgments are of the same object, but that the conditions for attaining it could not be met since we can never overcome the subjectivity of taste. such judgments are unavoidably variable, and variability is a condition of the situation. the challenge is to identify the causes of residual disagreement. kant introduced that guarantor of what cannot be proved, a deus ex machina, by appealing to a sensus communis, a pure construction, to establish human universality. whether this condition of indeterminacy can be overcome rests on how far one is willing to travel beyond the experience of beauty on an article of faith: hume not at all; kant gingerly but very far. hume and kant exhibited common features in the ways we often under- stand the problem of taste, and they illustrate traditional ways of adjudicating the problem. to reconsider the issue we need to question certain presump- tions pervasive in the philosophical tradition. this will make it possible to consider alternatives that will dramatically re-shape our understanding of such judgments. reconsidering scenic beauty environmental values . ii. presumptions of taste let us approach this issue differently by questioning an assumption common to such discussions as this. it is an idea that hume and kant undoubtedly took for granted, as many still do today, and it appears in the very structure of the problem. for them the problem of taste is that the difference in our judgments rests on the disparity between the experience of beauty, and hence the subjectivity of appreciation, and the independence of the normative object toward which our judgment is presumably directed. this division structures the issue in such a way that the difference cannot be reconciled: it is dif- ficult for feeling to conform to logic. more than this, disappointment at not succeeding is unavoidable because the underlying presumption is that an objective judgment of its beauty must be both possible and desirable since there is an independent object of appreciation. such reasoning is, however, fatally circular because it is doubly assumptive and consequently doubly false. judgments must concur because knowledge must be universal, people are similar, and so is the object of their appraisal. but such universality cannot merely be assumed or claimed: it is precisely what needs to be proved. people’s perceptual acuity varies, their capacity for focused attention is different, and even more variable are their experience and education. in the light of such facts, the extent of actual agreement is surprisingly often considerable, even though not universal. variable, too, is the scenic object. not only does a scenic view change constantly with every breath of breeze, every cloud movement, as well as the changes of light and shadow caused by the continuous movement of the sun along its trajectory. less noticeable, perhaps, but even more significant is the transitory relation of the observer to the scene, where mood, disposition, and slight shifts in stance and location cause alterations in the scene, compounding its vari- ability. as there is no stable object, there is no stable viewer. whatever reconciliation of the disparity in judgment that thinkers fol- lowing hume and kant can claim actually rests on several articles of faith. for hume it was the assumption that there is an independent object toward which individual experiences veer and that, if they conform to the traits of that object, the judgments must concur. that they do not always agree he attributed to differences in sensibility, customs and experience. kant’s appeal to a sensus communis is to an unsupported assumption, a pure fabrication founded on an assumed intellectual necessity and limited evidence and not on observation. it is a concept constructed out of air. this situation exemplifies john dewey’s observation that the problems of philosophy are for the most part the problems of philosophers and not arnold berleant environmental values . the problems of other people. it is not the first time that philosophy has tied itself up in knots of its own making, and this is nowhere more evident than in attempts to objectify the world. we persist in following kant in think- ing we can speak to some degree meaningfully of what lies beyond human perception. william james recognised the limitation inherent in the notion of an independent objectivity when he noted ‘the general law of perception, which is that whilst part of what we perceive comes through our senses from the object before us, another part (and it may be the larger part) always comes out of our own mind’. the contemporary chinese aesthetician wangheng chen nicely expressed the extent of the human contribution when he observed that ‘fundamentally, beauty, including natural beauty, is a product of the humanisation of nature’. we might even consider emulat- ing kant’s understanding, which unfortunately he himself did not follow consistently, and recognise that what lies beyond perception utterly eludes human knowledge. the wisdom of the east may express this best of all: ‘the greatest beauty exists in nature (sky and earth), but at the same time it keeps silence.’ and even the physicist werner heisenberg noted that ‘when we speak of a picture of nature…we do not actually mean any longer a picture of nature, but rather a picture of our relation to nature’. when it comes to one’s basic grasp of the order of things natural and social, the process of emancipation is even more difficult. the literature on ideology is far exceeded by the literature of ideology. that is one reason why, in the industrialised west, the separations that divide things are so pervasive and powerful. the world we have constructed is a world of discrete objects separated from one another, objects and events that, like leibniz’s monads, are related only externally. it is a world of discrete individuals, a world of integers. and to call a world of independent, external objects ‘realism’ is to beg the question, for beneath this monadic order lies the most basic separation of all, our cartesian inheritance of subjective consciousness insulated from an objective world. this is a division comfortable because it is customary. the fact that this imposes a template on experience is overlooked. many things lead us to question this claim to adequately reflect the world. a philosophical critique of cartesianism demands its own inquiry, but it may be worth looking at evidence that suggests an alternative. a body of related data may weigh more heavily than an extended argument. here, then, are several considerations. reconsidering scenic beauty environmental values . iii. an empirically-grounded aesthetics theoretical developments in psychology and sociology over the last century have profound significance for aesthetic theory. the accounts of perceptual experience they offer are directly relevant, since aesthetics is itself grounded in experience. and they contribute to a reconsideration of taste. let me begin with etymology. the etymological reason is definitive but not conclusive. it is well known that the term ‘aesthetics’ is a transliteration of the greek aisthēsis, whose literal meaning is perception by the senses, and that the discipline of aesthetics was established by baumgarten, who defined ‘aesthetics’ as ‘the science of sensory knowledge directed toward beauty’ and ‘art’ as ‘the per- fection of sensory awareness’. the very identity of aesthetics rests on the centrality of sense perception: perceptual experience as the basic dimension of appreciation, perceptual experience as underlying the creative process (pace croce and collingwood), and perception as central for the practice of criticism insofar as this directs appreciation and judgment to the experience of art objects. all this signifies that the meanings, concepts and theoretical structures of aesthetics, many of which originated in speculative epistemol- ogy and metaphysics, may be poor guides in a field that is fundamentally experiential. this has critical relevance to problems involving aesthetic judgment, particularly judgments of taste. coming at this from other directions, we need to recognise what psycholo- gists of perception have long noted, that humans’ relation to things is not a relation between discrete and self-sufficient entities. on the contrary, just as people impose themselves on things, so, too, do things exercise an influence on people. among the classic contributions to psychological aesthetics are lewin’s field theory and his identification of invitational qualities; and j.j. gibson’s theory of affordances, features in an environment that encourage certain behaviour. much has been done by the successors to lewin and gibson in developing and elaborating their ideas and, while these views may not as yet have gained universal assent, they are widely recognised as influential. equally germane is the development over the past century of the sociology of knowledge, which has shown convincingly how social and cultural factors underlie the very conceptual structures in which we formulate and organise our knowledge of the world. sociological analysis also contributes to the empirical study of aesthetic judgment. one of the most forceful recent critics of aesthetic theory is pierre bourdieu. his extended study, distinction: a social critique of the judge- ment of taste, develops at length the thesis that ‘[s]ocial subjects, classified arnold berleant environmental values . by their classifications, distinguish themselves by the distinctions they make, between the beautiful and the ugly, the distinguished and the vulgar, in which their position in the objective classifications is expressed or betrayed’. bourdieu applied this analysis of taste widely and with special effectiveness to kant: ‘kant’s analysis of the judgment of taste finds its real basis in a set of aesthetic principles which are the universalisation of the dispositions associated with a particular social and economic condition.’ thus not only is taste variable because of social class differences; its very philosophical consideration finds its formulation shaped by similar influences. in fact, bourdieu claims, kantian disinterestedness, the basis for the discrimination of the pure pleasure afforded by beauty from interested enjoyment, indeed the critique of judgment itself, is based on a sense of distinction that marks an invidious social relation. but there are more empirical data to be considered, for in addition to psychological and sociological evidence, it is now widely recognised that agreement is widely grounded on culture, and here the comparative study of aesthetics is important. in one such study, the anthropologist robert plant armstrong describes art as the work of ‘affecting presence’. he abandons the ethnocentrically identified assumption that all works we call ‘art’ pos- sess the same aesthetic properties and that these underlie our judgments of beauty and virtuosity. the presumption of such a universal aesthetic, he argues, is challenged by non-western cultures that exhibit how observable aesthetic beliefs and behaviour are as variable as institutions and every other social construction. aesthetic values in these cultures do not rest on beauty but derive from what armstrong calls the embodiment and management of powers. using african and upper paleolithic work, he argued that concepts of beauty, truth and excellence have little to do with the inherent cultural value of an object, and he developed an aesthetic typology that integrated human consciousness and its reification as art. art thus becomes the work of ‘affecting presence’ embodying in mythic configurations the mammalian, human, cultural and autobiographical features of consciousness. the pres- ence that is established is affecting because of the power ascribed to myth, and this presence determines the realm of the aesthetic. it is also important to include here philosophical developments that of- fer alternative structures for understanding humans’ standing in the world. among these we can include maurice merleau-ponty’s efforts to identify the continuities that express the embeddedness of humans in the world. these include such ideas as the flesh of the world, as well as the ‘chiasm’, which identifies the reciprocity that permeates human relations with self, other living beings, and the features and objects of the natural world. similar efforts to reconsidering scenic beauty environmental values . formulate these connections were made by gilles deleuze and félix guattari when they spoke of the experience of ‘becoming’ as a desubjectification that precedes the distinction of self and object. i have long been working with the concept of an aesthetic field, which identifies and explicates the holistic situational context of aesthetic experience. general understanding usually lags generations behind major scientific developments, and philosophic theory is no exception. scholarly conscious- ness (not to mention popular understanding) is still struggling to accommo- date the implications of relativity theory and quantum mechanics, and of the qualifications of scientific knowledge demanded by heisenberg’s principle of indeterminacy and other such revolutionary cognitive developments. the implications of conceptual changes like these have powerful consequences for aesthetic conventions. these developments carry conceptual changes that profoundly affect the place of humans and the human world. nothing is more fundamental and nothing has greater consequences for aesthetic theory, and conventional views of aesthetic experience cannot accommodate such a change. on one side of the ledger, analytic aesthetics focuses on the art object, or sometimes, as monroe beardsley did, on the aesthetic object: its qualities, its features, its historical setting, its relations with other objects, its actions and effects and the actions and effects of other things on it, and, perhaps centrally, the critical statements – descriptive, interpretative and evaluative – we make about such objects. such objects occupy a place in an orderly world and the task of aesthetics is to demarcate that place clearly. science figures here as a model of conceptual clarity and epitomises the cognitivist orientation of analytic aesthetics. on the other side, insofar as we can identify distinct alternatives, are traditions associated with what is commonly called continental aesthetics, movements that include aspects and influences coming from phenomenology, hermeneutics, post-structuralism and post-modernism, with some influences from critical theory, feminism and the philosophy of culture. art here tends to be seen as ‘the sensuous embodiment of conscious enquiry’, affecting our understanding of how we relate and ‘interact with other objects and minds’. emphasis is placed on the body, bodily sensation and our senses, and on the historical and cultural influences that pervade our understanding. continental aesthetics embraces diverse movements, certainly, but a feature frequently found in this work is a focus on subjectivity, consciousness and inter-subjectivity in the process of aesthetic understanding. these are trends in aesthetic thought and do not define the parameters of the work of any specific scholar, nor are they sharply divided. differences occur in emphasis and approach, and trends and resemblances are present arnold berleant environmental values . and apparent both within and between diverse approaches. yet as conceptual orientations, both suffer from partiality and incompleteness. the philosophical investigations of merleau-ponty, deleuze, guattari and other more recent scholars, together with critical insights from psychology and sociology, offer a still different view of the world of aesthetic understanding. this is a vision that is able to accommodate both the consistency and variability in aesthetic perception. how can we best conceptualise this understanding of aesthetic judgment? let us consider an account of aesthetic experience that is compatible with this body of empirical data and provides a more comprehensive understanding of judgments of taste. iv. aesthetic engagement and aesthetic naturalism the concept of aesthetic engagement signifies human embeddedness and active participation in the experience of appreciation. rather than adopting a sense of distance in contemplating a landscape or an art object, engaged appreciation encourages a close involvement characterised by experiential reciprocity. in place of a separation between viewer and landscape, it affirms a continuity that is both physical and experiential. aesthetic appreciation encourages such personal engagement. while true in art, this experience is both encouraged and especially vivid in landscape appreciation, where it becomes not only visual but overtly somatic. such appreciation is an experience of physical presence that is implicitly or overtly participatory, projecting somatic awareness by virtual projection into the landscape or by actual movement through by it. when we make perceptual continuity central in aesthetic appreciation, we transform the problem of aesthetic judgment. in place of a dualism of viewer and landscape, perceiver and object, each of the pair reciprocates the other, and we have a situation in the form of an aesthetic field characterised by an actively perceiving human participant within and part of a sensory environment. every perceiver contributes to the situation, not only through perceptual activity, but with the invisible dimensions of past experience, memory, knowledge and conditioning – the whole range of personal and cultural factors that colour our active sensory experience, whether or not we are aware of it. this structural order of the aesthetic field is informed by the character of particular occasions. from such occasions of aesthetic appreciation, judgments of aesthetic value are formed, and we cognise these aesthetic events in the form of aes- thetic judgments. beauty then becomes the positive aesthetic designation of reconsidering scenic beauty environmental values . a particular aesthetic field, and the sublime a different, distinctive, usually positive designation. of course each situation has individual features that vary with time, place and participants, and our judgments of value are simi- larly variable. to the extent that occasions and participants share significant features, the aesthetic judgments formed of them will tend to agree. but time, experience and individual variability introduce irreducible differences, and because no two occasions are exact duplicates, judgments of them will thus rarely be unanimous. from an empirical standpoint, the variability of aesthetic judgment is no disability; it simply reflects the motile conditions of appreciative experience. only when a cognitive template is imposed on such experience is variability considered a defect. universality is a logical desideratum, not an empirical one. at the same time, the actual extent of variability is not infinite. despite social and psychological dissimilarities, humans’ biologically based sensory capacities are very much alike. to the extent that these resemblances are intensified by a common culture, agreement will be the greater, but where there is no common culture, there will be less agreement. in all this, however, disruptive factors lie in the very differences and influences that hume noted. insofar as experience and knowledge are added to interest and perceptual sensitivity, these will be reflected in expert judgment. and variation in expert judgment is no disability: like all judgment, this is itself open to reflective deliberation and empirical testing. this view carries important implications, not only for landscape appre- ciation but for judgments of taste in general. the experience of landscapes, the experience of nature more generally, identifies a relationship even more than a relation, a situation that finds the human embedded within and part of every experiential context. thus in speaking about engaging landscapes, we identify not only an aesthetics of environment but also a metaphysics. how we experience landscapes involves not only an inner feeling or a purely sensory event or a particular kind of aesthetic object. it is rather how we live in the world and the kind of world we inhabit. but how we live in the world and how we think and talk about it are often quite different from each other. formed by a cultural environment, we imbibe a consciousness of its order as part of our growing awareness. even in a society that allows discussion and debate, the possibility of a critical reconsideration of its parameters of thought is slow and uneven, even more perhaps than open reflection on religious or moral beliefs. under relatively stable conditions, when cultural change moves imperceptibly, reaction to such convictions, internalised along with other customs, habits and ideo- logical configurations during the early decades of life, rarely emerges for arnold berleant environmental values . re-evaluation to the point of emancipation or even of conscious acceptance. even violent opposition may not be a sign of emancipation from a cultural ideology but merely a sign of negation. it is difficult to combine impartiality and emotional neutrality with intellectual independence in order to identify and critically consider customary moral and religious beliefs and coolly appraise alternatives. understanding judgments of taste in a way that recognises the influence and force of invitational qualities, affordances, reciprocity, engagement and the pervasive influence of culture offers not only a logical alternative but a living alternative, one that provides an empirical grounding for critical reconsideration. such an account can accommodate the facts of appreciative experience and judgment without feeling distress over their variability. it is based on perceptual experience rather than on the requirement to conform to an a priori logical or epistemic criterion of universality. the extent of agreement is thus an empirical matter. it is no surprise that its scope is considerable, even though far from universal, considering the biological and cultural commonalities that bind people together. ludwig wittgenstein made a similar point when he averred that ‘it is … only where there is “agreement in … form of life” that there can be shared understanding of the meanings of words, gestures, practices …’. v. conclusion i am not proposing that we abandon aesthetics altogether, only that we reconsider the kind of contribution that philosophy is able to make. can we continue to maintain that beauty is something objective and universal, independent of empirical evidence? if so, then we risk being circular. on what other grounds can we retain the belief in the objectivity of beauty? metaphysical? mere assertion has no claim to acceptance. whatever contribu- tion philosophy can make must be germane to the conditions of its inquiry. it is not necessary to fully accept bourdieu’s reduction of taste to invidious social distinctions to acknowledge the force of his basic claim. philosophy, despite its origins and conduct as a discipline seeking and embodying eternal truths, cannot rise above its cultural origins. it cannot legislate itself out of its social and historical context and it is no more immune to such conditions than any other study. what is true for philosophy is especially applicable to aesthetics, a discipline grounded in perceptual experience, where we encounter a plurality of judgments of taste as varied as the conditions under which they are made. distinctions of taste, like all judgments of experience, reconsidering scenic beauty environmental values . are subject to the multiple somatic and cultural forces that influence them. any single factor, including social class, is unlikely to wholly determine the judgment. the same mix of differences that hume identified in the critic affects everyone. questioning the presumption that universality is cognitively necessary and the grounds for universality in an independent, objective world thus leads to a different understanding of judgments of scenic beauty and of taste in general. any discomfort we may feel from abandoning the quest for universality is the consequence of mistaken expectations, the product of a culture that has misunderstood not just the conclusions of the quest but its very conditions. further, it requires us to reconsider the contribution that philosophic inquiry can make in such matters. does empirical evidence require that we abandon philosophical claims to objectivity? at issue here is the question of what evidence is relevant. the history of philosophy displays many instances of grave discomfort over empirical evi- dence. from plato to descartes to the present, philosophers in a rationalistic tradition have too often dismissed empirical data as defective in principle. this is not the place to rehearse the long debate between rationalism and empiricism; it is necessary only to recognise that aesthetic inquiry, grounded necessarily in experience, cannot selectively choose (as kant did) only that evidence that is compatible with its rationalistic presuppositions. as aes- thetics is empirical, it must accommodate empirical data, and philosophical assertions that do not acknowledge such evidence cannot escape being ir- relevant. re-casting our understanding of judgments of taste, we may have to revise our understanding of philosophical aesthetics itself. what, then, can philosophy contribute here? with its sensitivity to the influence of presuppositions and its sharpened conceptual faculties, philosophical criticism is a powerful tool that has wide applicability. thus one function of philosophical query is its time-honoured critical one of cleaning out the augean stables, the purpose of this essay. but aesthetics can also have a constructive function. comparative aesthet- ics is one area in which discerning vision can identify resemblances and commonalities among different traditions and take note of irreducible dif- ferences. the growing interest in identifying contrasting features in western and eastern aesthetics offers a broad brush whose individual strokes may reveal illuminating subtleties. for the past century and more artists have drawn increasingly on non-western cultures: african sculpture, javanese music, aboriginal graphics, chinese gardens, japanese film, indigenous arnold berleant environmental values . architecture and local literatures. perhaps our philosophical sensibilities can be enriched as our aesthetic ones have been. this variability, far from being a shortcoming, actually provides a rich range of data ripe for inquiry by aestheticians, as well as by sociologists, psychologists, historians and anthropologists of art. aesthetics is a field whose subject is the endlessly varied and complex domain of human experi- ence, where scholars and scientists can acknowledge, respect and study the varieties of the aesthetic without prejudice. how varied are the standards within and among different cultures? what similarities do they possess and how do they differ? how have they changed over time and from outside influences? what significance do the answers to these questions have to the cultures in which these standards arise? can we identify the varied influence of biological commonalities and of the cultural appropriation of genetic predispositions? are the structure and course of appreciative experience similar among individuals and cultures? scenic beauty provides a vivid test for the variability of these judgments. and while we end with more ques- tions than we started with, there is a significant difference: these questions can, in principle, be answered. notes nicolson ( ) quotes john evelyn’s diary from , in which he writes about the alps ‘which now rise as it were suddenly, after some hundred miles of the most even country in the world, and where there is hardly a stone to be found, as if nature had swept up the rubbish of the earth in the alps, to forme and cleare the plaines of lombardy’. compare this to thoreau: ‘ what is a horizon without a mountain.’ journal, : . see carlson . he argues that ‘quantifying scenic beauty may be, even if possible, neither as useful nor as straightforward as much of the current work in environmental aesthetics would lead us to believe’ (p. ). although the terms and frame of carlson’s discussion differ from those of this paper, our conclusions are compatible. hume [ ], p. . loc. cit. hume’s characterisation of a ‘true judge’ is a person who possesses ‘strong sense, united to delicate sentiment, improved by practice, perfected by comparison, and cleared of all prejudice….’ op. cit., p. . op. cit., passim. immanuel kant, critique of judgment, § . op. cit., p. . reconsidering scenic beauty environmental values . james , . wang heng chen, ‘on the beauty of nature’, unpublished manuscript, wuhan university, , p. . zhuang-zi, the most famous taoist after lao-tse. werner heisenberg ( ). quoted by macaulay, access index # ). alexander gottlieb baumgarten, aesthetica (frankfurt a. o., ), vol. i. berleant . bourdieu , p. . ibid., p. . nietzsche may have been making a similar point about kant: ‘kant wanted to prove in a way that would dumbfound the common man that the common man was right: that was the secret joke of this soul. he wrote against the scholars in favour of the popular prejudice, but for scholars and not popularly.’ friedrich nietzsche, the gay science , § . ibid., pp. - . armstrong ; . first developed in berleant l a. i have discussed this work more extensively in berleant , chs. - . cf. beardsley . cazeaux , iv–vii. see berleant ; ; and subsequent publications. wittgenstein , e, § . the text here is, ‘ ‘so you are saying that human agreement decides what is true and what is false?’—it is what human beings say that is true and false; and they agree in the language they use. that is not agreement in opinions but in form of life.’ quoted by cooper , . in a similar critique of disinterestedness, bourdieu noted that ‘[e]mpirical’ interest enters into the composition of the most disinterested pleasures of pure taste, because the principle of the pleasure derived from these refined games for refined players lies, in the last analysis, in the denied experience of a social relationship of membership and exclusion….[ posi- tions regarded as inferior are] stigmatized as ‘empiricism’ or ‘historicism’ (no doubt because they threaten the very existence of philosophical activ- ity)…. op. cit., p. . bourdieu sees the hierarchy of taste, from vulgar to refined, as reflecting the distinc- tions of social class, and the intellectual apparatus elaborating and justifying those distinctions as embodying the very same class distinctions. aesthetics, and philosophy more generally, he claims, are not free intellectual inquiry but are class-prejudicial from the start. philosophy itself embodies the distinctions that mark social relations in the normativity of its own distinctions. in short, the philosophical sense of distinction is another form of the visceral disgust at vulgarity which defines pure taste as an internalised social relationship, a social relationship made flesh, and a philosophically distinguished reading of arnold berleant environmental values . the critique of judgment cannot be expected to uncover the social relationship of distinction at the heart of a work that is rightly regarded as the very symbol of philosophical distinction. op. cit., pp. – . i made a similar critique of the history of ethical theory in berleant b. cf. sasaki . references armstrong, robert plant . the affecting presence: an essay in humanistic anthropology. urbana: university of illinois press. armstrong, robert plant . the powers of presence: consciousness, myth, and affecting presence. philadelphia: university of pennsylvania press. beardsley, monroe c. . aesthetics: problems in the philosophy of criticism. new york: harcourt, brace & world. berleant, a. a. the aesthetic field: a phenomenology of aesthetic experience. springfield, ill.: c. c. thomas. second (electronic) edition, with a new preface ( ) . berleant, a. a. ‘the social postulate of theoretical ethics’, journal of value inquiry iv(l): l–l . berleant, arnold . art and engagement. philadelphia: temple university press. berleant, arnold . the aesthetics of environment. philadelphia: temple university press. berleant, arnold . sensibility and sense: the aesthetic transformation of the human world. edinburgh: imprint academic. bourdieu, pierre . distinction: a social critique of the judgement of taste. cambridge, ma: harvard university press. carlson, allen . ‘on the possibility of quantifying scenic beauty’. landcape planning : – cazeaux, clive (ed.) . the continental aesthetics reader. london and new york: routledge. cooper, david e. . a philosophy of gardens. oxford: clarendon press. hume, david [ ]. ‘of the standard of taste’, in of the standard of taste and other essays (bobbs-merrill). james, william . psychology. holt. nicolson, marjorie hope . mountain gloom and mountain glory: the development of the aesthetics of the infinite. new york: w.w. norton. sasaki, ken-ichi . asian aesthetics. kyoto: kyoto university press. wittgenstein, ludwig . philosophical investigations. oxford: blackwell. beautymitosis.indd caryologia *corresponding author: e-mail: waheeb.heneen@slu.se vol. , no. : , two dvds on ”the beauty of mitosis” waheeb k. heneen department of plant breeding and biotechnology swedish university of agricultural sciences, p.o. box , alnarp, sweden university version: https://www.createspace.com/ school version: https://www.createspace.com/ both versions: https://www.createspace.com/ cytologists who have seen the fi lms on mitosis made by andrew bajer and jadwiga molè-bajer during the th cannot forget the impression these fi lms made by portraying the dynamics of mitosis in a captivating way. the fi lms were re- ceived, and still are considered as among if not the best educative fi lms on mitosis. the fi lms doc- umented nuclear division in endosperm tissues of blood lily haemanthus katharinae (now named scadoxus multifl orus ssp. katharinae). the bajers developed the technique of maintaining the en- dosperm tissues alive during phase contrast mi- croscopy and time-lapse cinematography of the mitotic process, using an assembled movie cam- era. they also visualized mitosis in scadoxus using other microscopic approaches such as bright fi eld and differential interference contrast microscopy as well as transmission electron microscopy. recently, the bajers selected some of their time-lapse fi lms and converted them to a digital form. the digital fi lm sequences, schematic draw- ings of the mitotic stages and still pictures using bright fi eld and differential interference contrast microscopy, supplied by the bajers, together with some of my scanning electron pictures, all on sc- adoxus, constituted the pictorial material for the edition of a dvd on mitosis. two dvd versions were made titled “the beauty of mitosis: university version” and “the beauty of mitosis: school version”, min and min long, respectively, by andrew s. bajer, jadwiga a. molè-bajer and waheeb k. heneen. in the beauty of mitosis: university version, various aspects of normal mitosis, spontaneous aberrations and effects of chemicals, uv-irradi- ation and x-rays are exemplifi ed. features such as duration of mitosis, behaviour of ring chromo- somes, colchicine effects, multipolar division as well as chromosome nondisjunction and break- age are elucidated. phase contrast cinematogra- phy is complemented with schematic drawings and photographs of the different stages of mitosis as seen after bright fi eld, differential interference contrast and scanning electron microscopy. the detailed university version is an educational fi lm meant for university students and researchers, as a complement to genetic and cytology courses in life sciences and medicine. in the beauty of mitosis: school version, phase contrast cinematography of normal mito- sis, chromatin condensation and the duration of mitotic stages are complemented with schematic drawings and bright fi eld photographs of the mitotic stages. features of aberrant mitosis are exemplifi ed by chromosome nondisjunction and fragmentation induced by exposure to uv-irradi- ation and x-rays. the short school version is an educational fi lm meant for school students, as a complement to the lectures of biology teachers. in both versions, necessary explanatory text is added. fitting well as background music is chopin´s piano concerto no. . the prime goal of making these dvds is to have the bajers “unique” fi lms accessible for cytology scholars and biology students. the dvds have been released through createspace.com in october . my contribu- tion is just the edition work of the two versions and contribution with scanning electron micro- scope pictures in the university version. letters and comunications the last page of each number will be dedicated to the relationship with authors and readers. com- munication by the editorial board and letters by authors will be published here. the editor to the readers of our journal dear authors, the authors who must pay the reduced subscription are solicited to accomplish their duty by bank remittance to: unicredit s.p.a via volturno / sesto fiorentino - osmannoro (fi) iban: it / / h / / / swift (bic): uncritm f registered to university of florence -polo scientifi co di sesto e agraria-caryologia. published giugno th editore: università degli studi di firenze registrazione tribunale di firenze n. del / / redazione: dipartimento di biologia vegetale via la pira, - firenze direttore responsabile: dr. alessio papini stampato a firenze da edizioni tassinari - firenze - giugno pnas _ _s .. cortical evolution in mammals: the bane and beauty of phenotypic variability leah a. krubitzera,b, and adele m. h. seelkea acenter for neuroscience and bdepartment of psychology, university of california, davis, ca edited by francisco j. ayala, university of california, irvine, ca, and approved april , (received for review march , ) evolution by natural selection, the unifying theory of all biological sciences, provides a basis for understanding how phenotypic variability is generated at all levels of organization from genes to behavior. however, it is important to distinguish what is the target of selection vs. what is transmitted across generations. physical traits, behaviors, and the extended phenotype are all selected features of an individual, but genes that covary with different aspects of the targets of selection are inherited. here we review the variability in cortical organization, morphology, and behavior that have been observed across species and describe similar types of variability within species. we examine sources of variability and the constraints that limit the types of changes that evolution has and can produce. finally, we underscore the importance of how genes and genetic regulatory networks are deployed and interact within an individual, and their relationship to external, physical forces within the environment that shape the ultimate phenotype. evolution is the change in heritable, phenotypic characteristicswithin a population that occurs over successive generations. the notion that biological life evolves and that animal forms descend from ancient predecessors has been considered for centuries and, in fact, predates aristotle ( ). however, charles darwin was the first to articulate a scientific argument based on extensive observations for a theory of evolution through natural selection. darwin’s theory contains three basic tenets: individuals within a group are variable, variations are heritable, and not all individuals survive ( ). survival is based on selective advantages that particular phenotypic characteristics or behaviors confer to some individuals within a given environmental context. although in darwin’s time our understanding of the brain was in its infancy and mendel’s laws of inheritance were little appreciated, dar- win’s assertions regarding evolution through natural selection of adaptive traits, was, and still is, compelling. recently our understanding of the mechanisms underlying evo- lution has become more sophisticated, and we appreciate that slight variations in gene sequence can be correlated with alterations of traits and behaviors within and across species. however, an im- portant but often overlooked distinction is the difference between the targets of selection (i.e., phenotypic variations) vs. what natural selection passes on to the next generation (i.e., genes). although genes are the heritable part of the equation and have a causal, al- though not always direct, link with some characteristic of the phe- notype, genes are not the targets of selection. genes are indirectly selected for because they covary with the targets of selection, and if the target of selection is adaptive, then genes or portions of the genome replicate and produce a long line of descendants. the di- rect target of selection is multilayered but can be thought to center around the individual and the unique phenotypic characteristics and behaviors that it displays. these characteristics include external morphology such as color, size, jaw configuration, digit length, and bone density, to name a few. this physical variability in the phe- notype is also accompanied by variability in behavior, such as uti- lization of individual specialized body parts, as well as more complex whole-animal behavior such as intraspecies communica- tion. based on the assumption that the gene’s success is due not only to the individual’s success but to its effects on the world, dawkins ( ) proposed the idea of an “extended phenotype,” wherein a gene can find its expression in the body of the next generation or in a created environment that perpetuates its success. for example, bowers built by bower-birds are variable and have variable success in attracting mates. inasmuch as the structure of the bower is linked to the phenotypic expression of some behavior that has causal links to one or several genes, the bower is part of an extended phenotype of the bower-bird. thus, phenotypic expres- sion can occur outside of the individual’s body and include in- animate objects used for niche construction and can even include the social niche constructed by differential behaviors of individuals within a population. because the measure of evolutionary success is reproduction, it follows that the targets of selection must also in- clude covert features of the phenotype that keep the individual alive long enough to reproduce, such as differential resistance to infection or adeptness at reading social cues. although our focus is how brains are altered through the course of evolution, brains, like genes, are not the direct targets of se- lection. genes are the heritable components that covary with aspects of brain morphology, connectivity, and function, and in this context, provide a scaffold for brain organization. the brain in turn generates behavior. ultimately, it is the behavior of a pheno- typically unique individual along with its extended phenotype that are the direct targets of selection. thus, although genes (not individuals) replicate themselves through generations, their link to selection is indirect and convoluted. of course, an important question is how genes and aspects of brain organization covary with each other and with the targets of selection. associated questions include these: how variable are features of brain orga- nization? how variable is gene expression and gene deployment during development within a population? in addition, what factors contribute to this multilayered variability of the organism? we address these questions from a comparative perspective. first we examine aspects of the cortical phenotype that are ubiq- uitous across species because of inheritance from a common an- cestor (homology). we then describe how these characteristics vary across species. we contend that the ways in which homologous features vary provide an important insight into the more subtle variations that might be present in individuals within a population. finally we discuss the external and internal mechanisms that give rise to cross-species and within-species variation and the con- straints these forces exert on evolution. phenotypic similarity and variability across species there is a general plan of neocortical organization that has been observed in all mammals investigated. this includes a constella- this paper results from the arthur m. sackler colloquium of the national academy of sciences, “in the light of evolution vi: brain and behavior,” held january – , , at the arnold and mabel beckman center of the national academies of sciences and engi- neering in irvine, ca. the complete program and audio files of most presentations are available on the nas web site at www.nasonline.org/evolution_vi. author contributions: l.a.k. and a.m.h.s. wrote the paper. the authors declare no conflict of interest. this article is a pnas direct submission. to whom correspondence should be addressed. e-mail: lakrubitzer@ucdavis.edu. this article contains supporting information online at www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental. www.pnas.org/cgi/doi/ . /pnas. pnas | june , | vol. | suppl. | – d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.nasonline.org/evolution_vi mailto:lakrubitzer@ucdavis.edu http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental www.pnas.org/cgi/doi/ . /pnas. tion of cortical fields involved in sensory processing, such as pri- mary visual (v ), somatosensory (s ), and auditory (a ) areas (fig. ; table s for abbreviations) ( ). these homologous fields share similar patterns of connectivity from both the thalamus and other cortical fields, a common architectonic appearance, and neurons within these fields have similar properties ( ). these observed similarities allow us to infer the cortical organization of the common ancestor of all mammals (fig. ) and underscore the constraints imposed on the evolving nervous system. for example, the visual system in blind mole rats is used only for circadian functions, and not for visual discrimination. yet, v is still present, as are geniculocortical connections ( , ). however, v is greatly reduced in size, neurons in v respond to auditory stimulation, and subcortical connections of auditory pathways have been rerouted to the lateral geniculate ( – ). comparative studies also allow us to appreciate deviations from this organization that have occurred over evolution. surprisingly, the systems-level alterations to the mammalian neocortex are limited (fig. ). one among these is a change in sensory domain allocation. this specialization begins in the pe- riphery with a relative increase in the innervation of a sensory ef- fector organ, followed by an increase in the size of subcortical structures that receive inputs from this effector organ, an increase in the amount of thalamic territory to which these structures project, and ultimately an expansion in the amount of neocortex devoted to processing inputs from a particular sensory system ( – ). cortical fields within a sensory domain can also vary, both in their overall size and in the size of the representation (or cortical magnification) of specialized morphological features, such as the nose of a star-nosed mole or the bill of a platypus (fig. ). cortical fields can vary in connectivity with cortical and subcortical struc- tures, and the number of cortical fields varies across species. the persistence of both a common plan of organization, even in the absence of use, and the limited ways in which this plan has been independently altered suggest that there are large constraints im- posed on evolving nervous systems. species also vary in the peripheral morphology of homologous body parts and the use of these structures. a good example is the glabrous hand of humans, the pectoral fin of a dolphin, and the wing of a bat (fig. ). the hands of humans have undergone several important changes, including alterations in the size of the distal, middle, and proximal phalanges. the carpal and meta- carpal joints, the articulation between the first and second car- pals, and the metacarpophalangeal joints underwent significant change, as did the size and position of associated ligaments ( ). the distal digit tips also evolved a high concentration of tactile receptors with a high innervation density. these transformations allow for an expanded repertoire of grips, including a precision primates common ancestor marsupials placentals chiroptera carnivores monotremes rodents mouse opossum platypus echidna flying fox ghost bat cat macaque chimpanzee marmoset squirrel human new world monkeys old world monkeys great apes hominids primary somatosensory area (s ) primary auditory area (a ) primary visual area (v ) fig. . cladogram of phylogenetic relationships for the major subclasses of mammals. all species examined have a constellation of cortical fields that includes primary somatosensory, visual, and auditory areas (see color codes). however, their relative size and location has been altered in different species. modifications to the neocortex size of cortical sheet sensory domain allocation relative size of cortical fields magnification of behaviorally addition of modules number of cortical fields connections of cortical fields s v a modules in v specialized body part in s other somatosensory areas a b c d e f g relevant body parts fig. . schematic of the types of cross-species, systems-level modifications that have been observed in the neocortex. the outline of the boxes indicates the entire cortical sheet, and smaller boxes within represent either cortical domains (b), cortical fields (c and e–g), or representations within cortical fields (d). these same types of changes have been observed across individ- uals within a species, but they are often less dramatic. duck-billed platypus star-nosed mole raccoon rat cortical magnification specialized body part representation in s other body part representations in s specialized body part represenation in other areas a c b d fig. . examples of cortical magnification for (a) the bill of the platypus, (b) the nose tentacles of the star-nosed mole, (c) the hand of the raccoon, and (d) the whiskers of the rat. the representation of the specialized morpho- logical structures in s is red and in other cortical areas is pink. gray indicates the representation of the rest of the body in s . | www.pnas.org/cgi/doi/ . /pnas. krubitzer and seelke d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , http://www.pnas.org/lookup/suppl/doi: . /pnas. /-/dcsupplemental/pnas. si.pdf?targetid=nameddest=st www.pnas.org/cgi/doi/ . /pnas. grip. although these adaptations are proposed to have evolved for tool use ( ), in modern humans the hand is also used for playing instruments and other nontool-related activities. in dolphins the homolog of the primate hand is the pectoral fin. the fin has undergone several important morphological changes including a transition from bone to soft cartilaginous tissue, elongated digits with additional joints (hyperphalangy), atrophied triceps, immobilization of most of the joints, and lack of most connective tissue structures ( ). these alterations to the forelimb allow for different properties and functions associated with loco- motion in water, such as increased lift, reduced drag, and the ability of execute turns and braking ( ). however, recent studies indicate that fins are also used in “flipper rubbing,” which involves the physical contact between one dolphin’s fin and another dol- phin’s body or fin and likely has important social functions ( ). finally, in bats, the wing is the homolog of the hand and fin. digits – form the wing, and digit is unattached from the rest of the wing and used for climbing. although bats have little to no ability to grip or manipulate objects with this highly derived structure, wings are of course well adapted for self-propelled flight (see ref. for review). between the elongated digits, elastin-col- lagen bands or membranes have evolved. these are covered with small, specialized receptor assemblies, termed touch domes, which are exquisitely sensitive to very small changes in air pressure ( ). these structures are thought to be used for sensing wing mem- brane strain during sharp turns, monitoring boundary layer airflow, and locating, tracking, and assisting in the transfer of wing-cap- tured prey to the mouth ( ). in species in which the neocortex has been explored and related to such extraordinary morphological specializations, correspond- ing alterations have been noted, including cortical magnification within sensory areas (e.g. refs. – ), and in some instances an extreme magnification in higher-order cortical areas, such as area in macaque monkeys (see fig. b) ( ). alterations in neural response properties [e.g., rapidly and slowly adapting direction selectivity ( , , )], architectonic appearance (e.g., ref. ), and connectivity have also been observed. thus, changes in aspects of cortical organization covary with alterations in periph- eral morphology and the very unique behaviors associated with this morphology. one can also compare body parts that are analogous, or have the same function. in human and nonhuman primates the hand is one of the main effector organs used to explore nearby objects or space. other species use different effector organs for exploration, such as the platypus’s bill, the rat’s vibrissae, and the nose of the star-nosed mole. although these structures may not be homologous they have a similar function, and in turn they share similar features of or- ganization of the neocortex, which have emerged independently. in addition to cortical magnification of the main effector organ in different sensory areas (fig. ), similar but independently evolved patterns of connectivity have emerged between motor cortex and posterior parietal cortex, despite the differences in body parts used to explore the immediate environment. perhaps the most compelling example of this phenomenon is the independent evolution of an opposable thumb and precision grip in old world monkeys and only one new world monkey, the cebus monkey. a repertoire of behaviors associated with this hand morphology includes complex manipulation of objects and tool use in the wild. in terms of neural organization, cebus monkeys have independently evolved a relatively larger cortical sheet, such that their encephalization ( , ) resembles that of distantly re- lated old world monkeys rather than their closely related sister groups, new world monkeys. in addition, they have indepen- dently evolved direct corticospinal projections to the ventral horn motor neurons that project to muscles of the digits ( ) and have also independently evolved a cortical field, area , associated with processing proprioceptive inputs ( ). this example illustrates two important points. first, hand morphology associated with specialized use covaries with cortical sheet size, cortical field addi- tion, and corticospinal connections. second, the independent evo- lution of these striking features of the morphological, behavioral, and cortical phenotype suggests that there are strong constraints on how complex brains and behaviors evolve. the types of cross-species comparisons described above inform us about what types of phenotypic changes have occurred, how homologous aspects of brain organization vary across species, and clearly indicate that evolution of brain, morphology, and behavior is constrained. however, they do not tell us how these phenotypic transitions occur and what factors contribute to or constrain phenotype diversity. because cross-species variability had to be- gin as within-species variability, we can understand the process of speciation by looking at individual variability. within-species variability phenotypic variability within a population is the cornerstone of evolution by natural selection, yet most studies of neural organi- zation and connectivity underscore the similarities across indi- viduals within a group rather than their differences. as a result, there are few studies that directly examine and quantify naturally occurring differences in features of nervous system organization within a species. as noted in our introduction, we reasoned that the most likely place to observe measurable within-species dif- ferences is in the features of organization that demonstrate dra- matic variability across species, like cortical field size and sensory domain allocation, and that are related to or covary with the tar- gets of selection. at a gross morphological level, animals with a large neocortex show variations in the size and configuration of sulcal patterns. within-species variation is also observed in the size of cortical fields in rats ( ), opossums ( ), squirrels ( ), and both non- human ( ) and human primates ( ). intraspecies comparisons of the size of v in humans and nonhuman primates reveal a high degree of variability, ranging from % to % with respect to the entire visual cortex (see ref. for review). in rats, riddle and purves ( ) observed that both the overall size of s and the proportion of cortex devoted to different body parts, such as the lip, barrel field, and forepaw, varied significantly across animals and even across hemispheres in the same rat. our laboratory di- rectly examined intraspecies variability in the primary sensory areas of opossums (monodelphis domestica) and measured and compared their sizes across hemispheres for each animal and across individuals within a species. we found that the size of pri- mary cortical areas was similar across hemispheres but varied considerably across individuals ( ). based on recent comparative studies in rodents, we propose this variability was mediated by environmental influences. specifically, wild-caught rattus norve- gicus had a large v and a greater amount of variability in cortical field size than their laboratory counterparts ( ). although these studies did not demonstrate large variability in overall cortical sheet size, the amount of cortex that was allocated to individual cortical fields was variable. within-species variability has also been observed in the internal organization of both sensory and motor maps. for example, albus bat wing dolphin pectoral fin human handa b c fig. . (a) wing of a bat, (b) pectoral fin of a dolphin, and (c) hand of a human are examples of homologous morphological structures. although they are used for very different purposes, they are organized around the same basic skeletal frame (in gray). krubitzer and seelke pnas | june , | vol. | suppl. | d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , and beckman ( ) observed notable differences in the visuotopic organization of v and v in cats. variability in somatotopic or- ganization has been reported for the hand representation in pri- mates ( ). in addition, although not always directly measured or the focus of a study, examination of somatotopic maps generated from functional mapping studies indicates that the representation of different portions of the body in adjacent somatosensory areas, such as a, , and , is variable across individuals within a primate species (e.g., refs. and ). the differences in the somatotopic organization of these sensory areas are clearly present but not extreme. however, the within-species variability in topographic organization of higher-order areas, such as posterior parietal area , is remarkable (fig. b) (e.g., refs. and ). finally, when similar microstimulation parameters are used across animals, the functional organization of primary motor cortex (m ) is highly variable within many species, including mice ( ) (fig. a), rats ( ), squirrels ( ), and owl monkeys ( ). individual differences have also been observed in smaller units of organization within a cortical field, termed modules. for ex- ample, in rats the succinic dehydroxinase-rich barrels and barrel- like structures that represent different body parts vary in size be- tween individuals ( ). in owl monkeys and squirrel monkeys, myelin-rich isomorphs associated with the oral structures and digits vary in size (fig. d and e) ( , ), as do the digit iso- morphs for the digits in macaque monkeys, particularly d ( ). ocular dominance columns in v of squirrel monkeys can show extreme variability ( ). in some monkeys they are discrete, stripe- like bands, in others they are smaller and less distinct, and in some monkeys they are nonexistent (fig. c). as noted in the previous section, homologous fields vary in their patterns of connectivity across phyla and even across species within an order such as rodents (see ref. ). connectional studies of the neocortex in any mammal share two common features. first, if the sources of technical variability are minimized (e.g., placement of injection of anatomical tracer, age, rearing condi- tion), the majority of connections for a given cortical field are similar across individuals. second, the variability that does exist takes two forms: alterations in the density of common inputs and the presence of novel but sparse connections to some structures or areas in different individuals. recent studies also demonstrate that cellular composition varies within a population. for example, within the cortex of primates the total number of neurons varies between individuals by a factor of ∼ . (calculated from ref. ). in another study, wild-caught rats (rattus norvegicus) were found to have a larger percentage of neurons and a greater density of neurons in v compared with laboratory rats of the same species ( ). some of the within-species variations in cortical organization described above are undoubtedly linked with behavior, although the relationship is often nonlinear and indirect. however, exami- nation of certain aspects of organization, such as the size and cellular composition of the primary visual area, are correlated with diel patterns and lifestyle of an animal. these, in turn, are linked to alterations in the visual system, such as the emergence of two-cone color vision and a highly laminated lateral geniculate nucleus in the highly visual, diurnal squirrel (see ref. for review). these alterations, which cross multiple levels of organization, provide some insight into the relationship between the brain and behavior. although these brain–behavior relationships are interesting, there have been few studies of within-species variation that examined how sensory-mediated behavior covaries with some measurable aspect of the cortical phenotype. in contrast, studies of variability in behavior within a population abound. some of the best examples of behavioral/neural/genetic variation are in the field of behavioral neuroendocrinology. for example, numerous studies have demonstrated that gnrh (gonadotropin- releasing hormone) regulates reproduction through a cascade of intermediaries. this begins with regulation of luteinizing hormone (lh) and follicle-stimulating hormone (fsh) secretion by the anterior pituitary, which in turn stimulates sex steroid production and gametogenesis. these sexual steroids (estrogen and testos- terone) then bind to receptors in the brain in regions that regulate sexual behaviors. important for this review, the volume and pattern of gnrh secretion varies with external cues, such as photoperiod, food availability, stress, and conflict ( , ), which in turn gen- erates variable release of lh and fsh by the anterior pituitary and so on. natural variation in genes that regulate this pathway has also been demonstrated in different individuals within pop- ulations of deer mice and white-footed mice ( , ). thus, vari- ability in the brain and behavior can be generated through external or internal cues. thus far, we have discussed features of the cortex such as cortical field size, connectivity, and cellular composition that vary between and within species and are correlated with, and likely covary with, the targets of selection (i.e., behavior). given that mm µm motor map motor map area map area map s hand map s face map s face map s hand map mm mm mm mouse motor maps macaque area maps squirrel monkey ocular dominance columns owl monkey face isomorphs owl monkey hand isomorphs a b c d e fig. . examples of intraspecies variability for (a) motor cortex in mice (adapted from ref. ), (b) area in macaque monkeys (adapted from ref. ), (c) ocular dominance columns in squirrel monkeys (adapted from ref. ), (d) s architectonic isomorphs in the owl monkey face representation (adapted from ref. ), and (e) hand representation (adapted from ref. ). in mice, motor maps are grossly topographically organized but are locally fractured. a depicts motor maps from two different individual mice. each small square represents a microstimulation location that evoked a move- ment of a particular body part, color-coded according to the colored mouse body at top. in macaques (b), maps of posterior parietal area are highly variable and are fractured. area also demonstrates an extreme magnifi- cation of the forelimb. color codes of the hand and arm correspond to their representations in cortical maps. in squirrel monkeys (c) ocular dominance columns vary from highly distinct (leftmost square) to nonexistent (far right square). finally, the myeloarchitectonically distinct modules of the face (d) and hand (e) representations in s of owl monkeys vary in their specific size and shape between individual animals. color codes of the hand and face correspond to their representations in cortical maps. | www.pnas.org/cgi/doi/ . /pnas. krubitzer and seelke d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , www.pnas.org/cgi/doi/ . /pnas. genes or portions of the genome are linked to these neural phenotypic characteristics, which in turn are linked to behavior, it is not surprising that features such as the location, amount, and time of expression of the same gene or gene network are variable across individuals within a population. recent studies demonstrate that this variability is due to dif- ferential activation of genetic regulatory networks ( ). these networks are composed of transcription factors and genes (nodes) as well as regulatory interactions (edges). the level of differential gene expression can be robust (persistent under perturbation) or stochastic (nondeterministic and flexible) and in turn generate phenotypic characteristics that differ in the extent to which they are variable within a population. stochasticity of gene expression often results in more variable phenotypic char- acteristics of the individual, whereas robustness of a gene regu- latory network often, but not always, results in less variability of a phenotypic characteristic. not surprisingly, fundamental bi- ological functions, such as the cell cycle, cell growth, and tran- scription, are generally governed by robust regulatory networks, suggesting that high variability for these key functions is non- adaptive. it seems likely that the basic, ubiquitous mammalian constellation of cortical fields with its homologous patterns of connections is regulated by robust networks, because these fields persist even in the absence of use. other aspects of organization that are highly variable within and across species are likely sto- chastically regulated. in fact it has been suggested that there may be “core” gene regulatory networks that are conserved between species and that differential alterations in the nodes or the edges contribute to species-specific differences ( ). what factors contribute to phenotypic variability? there are two important factors that contribute to phenotypic variability: genes and external signals, the latter consisting of the distribution of physical stimuli in a particular environmental context. genes both intrinsic and extrinsic to the neocortex play an important role in shaping different features of cortical orga- nization. equally important are the patterns of sensory stimuli that the developing organism is exposed to, and by extension, the patterned activity within and across major effectors such as the retina, skin, and cochlea. transcription factors such as emx , pax , and coup-tfi regulate patterns of cell adhesion molecules (e.g., cadherins; see ref. for review) and are graded in their expression across the developing cortical sheet (fig. ). numerous studies have shown that transcription factors and their downstream target genes covary with aspects of cortical organization, such as cortical field size, location, and connectivity (see ref. for review), and de- letion or overexpression of these factors results in changes in gene expression, contractions and expansions in the sizes of cortical fields, and altered patterns of connectivity from the dorsal thalamus ( ) (fig. ). as we discussed previously, such genetic changes only indirectly affect behavior, the actual target of selection. the relationship between alterations in transcrip- tion factors and changes in the direct targets of selection is complex but has been demonstrated to some degree in the mouse. overexpression of emx increases the size of v but decreases the size of somatosensory and motor areas ( , ). when these mice were tested on sensorimotor tasks that assessed hindlimb and forelimb coordination, they performed significantly worse than wild-type mice. this study establishes a clear link between genes, cortical field size, and behavior and demonstrates how alterations in patterns of expression of transcription factors and their downstream targets can generate relatively large degrees of phenotypic variability in the cortex, which in turn generates variability in the target of selection. genes extrinsic to the neocortex can also affect cortical or- ganization. for example, homeobox genes from the hox family are highly conserved across animals and are involved in forelimb development ( , ). comparative studies between mice and bats indicate that expression of these genes is altered during development ( ) and thought to be involved in transforming the forelimb into a wing ( , ). this process is multilayered. hoxd expression is posteriorly shifted in the developing fore- limb at later developmental stages in bats compared with mice, which reduces some wing skeletal elements ( ). although bone morphogenic proteins (bmps) trigger apoptosis of interdigit membranes in mouse fore- and hindlimbs and the bat hindlimb, in the bat forelimb bmps are inhibited by gremlin so that interdigit membranes are maintained ( ). this reduction in bmps is accompanied by an increase in fgf in the apical ecto- dermal ridge and is responsible for the extended proximal to distal growth of the limb in the bat ( ). bmp triggers pro- liferation and differentiation of chondroctyes, which increases digit length in bats ( ). thus, the amount, timing, and position of expression of genes during early forelimb development can induce dramatic alterations in the structure of the forelimb. as noted earlier, these alterations in forelimb morphology and the use of the forelimb covary with the size and internal organization of the cortical field. compared with mice, bats have a larger forelimb representation within s , and the topographic features of the wing representation within s relate uniquely to its altered position while the bat is at rest ( , ). although phenotypic diversity in cortical organization is gen- erated by modifying these intrinsic and extrinsic genetic con- tingencies, these same contingencies also serve to constrain alterations to the phenotype. the complex relationship between morphogens, the transcription factors they regulate, and in turn the target genes that they regulate, has been well described by o’leary and sahara ( ). most of these relationships are con- tingencies in which the actions of one node in a genetic regulatory network alter the trajectory of another node, which can potentially alter genetic regulatory networks associated with a completely different feature of organization. such integration limits the magnitude of viable changes that can be made via genetic mech- anisms. although small alterations at early stages of these con- tingencies (e.g., morphogen or transcriptional factor gradients) can have a large impact on the resultant cortical organization (e.g., change in cortical field size), alterations early in this cascade are also more likely to result in a nonviable phenotype. this is sup- ported by the presence of certain cortical fields in some animals despite the lack of apparent functional use ( ), the limited ways in which the cortical phenotype has changed, and the convergent evolution of similar features of organization despite very distant phylogenetic relationships. while we have given many examples of phenotypic diversity in the present review, we could provide an equally compelling argument that this diversity is fairly restricted v a s m wild type emx emx ko coup-tf coup-tf ko pax pax ko sp sp ko fig. . graded patterns of expression of transcription factors (upper) in- volved in aspects of arealization such as location and size of cortical fields. knockout (ko; lower) of these transcription factors generates radically dif- ferent sizes and positions of cortical fields compared with wild-type mice (left). cortical fields are color-coded (see key at bottom). adapted from ref. . krubitzer and seelke pnas | june , | vol. | suppl. | d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , if one considers all of the possible ways in which information could be processed and behavior generated. extrinsic factors also generate phenotypic variability within the cortex. for example, the activity from different sensory effectors during development, and throughout life, affects brain organiza- tion. experiments from our laboratory in short-tailed opossums (monodelphis domestica) in which both eyes were removed before cortical and subcortical connections were formed demonstrate that all of what would be visual cortex contained neurons that were responsive to somatosensory and/or auditory stimulation. thus, sensory domain allocation was dramatically altered ( ). in addi- tion, architectonically defined v was significantly smaller, whereas s was significantly larger than in normal animals, and “v ” received altered projections from cortical and subcortical somatosensory and auditory structures ( ). similar results have been observed in anophthalmic mice ( ) and blind mole rats ( ). targets of selection shallow extended steep restricted shallow extended steep restricted small large goodpoor poor good few many few manylow high down updown small largesmall large small large increasedecrease slow fast short long small large updown up high energy prey with distinct auditory emission number of photonswind velocity slope of pax gradient auditory discrimination visual discrimination response time to changes in air pressure size of s size of v size of a slope of emx gradient regulation of fgf in apical ectodermal ridge proximal to distal limb growth regulation of gremlin regulation of of bmps apoptosis of interdigit membrane interdigit membrane size length of forelimb genetic event developmental process genetic event cortical phenotype body brain environmental context optimal phenotypic characteristic within a population genetic profile that co-varies with phenotype/developmental event current genetic profile/ phenotype inherited genetic profile/ selected phenotype gaussian distribution within a population fig. . schematic illustration demonstrating how covaration between the targets of selection, phenotypic organization, and genetic events could lead to inheritance of genes that generate a population of future individuals with a unique combination of phenotypic characteristics. blue shading corresponds to factors associated with forelimb morphology, and green shading corresponds to factors associated with brain organization. these are not mutually exclusive but interact to some extent (overlapped shading). the gaussian curves represent the range of naturally occurring variability in a specific characteristic, with narrower curves representing robust characteristics and wider curves representing stochastic characteristics. the black and gray circles represent the location of the optimal characteristic along the current distribution (solid curve). selection pressures will eventually push the population to a new distribution, centered around the optimal characteristic (dashed curve). in this example our species is an echolocating bat, and our environmental context is illustrated at the top. some of the targets of selection (gaussian curves inside the red, dashed oval) would be characteristics of the forelimb that allow for flight, as well as behaviors such as fast response time and good auditory discrimination. cortical phenotypic characteristics (located between the dark gray and red dashed lines) that underlie auditory and tactile discriminatory ability would include an increase in the size of s and a , as well as an increase in the wing repre- sentation within s . underlying developmental processes associated with wing formation include a decrease in apoptosis in the interdigit membrane and the growth of the limb. at the far perimeter (far left and far right) of this illustration are the genetic events that covary with aspects of the body and brain phenotypes. | www.pnas.org/cgi/doi/ . /pnas. krubitzer and seelke d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , www.pnas.org/cgi/doi/ . /pnas. in mutant mice in which the cochlea is dysfunctional but the eighth nerve is still present, all of cortex that would normally process auditory inputs contains neurons that respond to visual and so- matosensory stimulation, and the size of a is significantly re- duced, whereas the size of v is significantly increased ( ). finally, as noted above, alterations in cortical field size and neu- ronal density are observed in the same species of rat reared in radically different environments (wild-caught vs. laboratory). thus, loss of sensory receptor arrays, loss of sensory-driven activity, or reduced patterns of activity can alter cortical domain allocation, cortical field size, connectivity, and neuronal density. other studies specifically manipulate the sensory environment in which the animal is reared and examine the effects on neo- cortical areas. for example, when ferrets are exposed to early training on a single axis of visual motion, neurons in v become preferentially responsive to movement along that axis ( ). in rats, early and prolonged exposure to a particular auditory tone results in increased cortical magnification for that frequency in a ( ). these changes in the internal organization of a sensory field and neuron response properties are similar to the types of differences observed across species and can be induced early in development by altering the sensory environment in which the animal develops. thus, a high degree of phenotypic variability can be induced without invoking genetic mechanisms that control brain devel- opment. the cortex has evolved to match the sensory environment in which it develops and produce highly adaptive behavior for that context. although we have focused this review on how sensory systems and cortical areas are modified, if one considers both social and cultural influences on the brain as complex patterns of sensory stimuli that groups of brains generate, then the same rules of construction and modification apply. however, as with genes, the environmental factors that generate phenotypic variability also serve to constrain the types of changes that can be made to the brain. for example, although photons can be differentially distributed in an aquatic, cave, or terrestrial environment, they have the same intrinsic properties, are uniformly defined as a discrete quantum of electromagnetic energy, are always in mo- tion, and in a vacuum travel at the speed of light. these immutable characteristics of a stimulus that the nervous system must detect, transduce, and ultimately translate, constrain the evolution and construction of the effector organ that initially captures some portion of the spectrum of this energy, and also impacts how higher-level structures transmit specific information about its presence, magnitude, and dispersal within an environment. conclusions we have discussed phenotypic variability across and within species and conclude that the ways in which animals and brains change are limited and predictable. further, we show that a specific charac- teristic, such as the size of a cortical field, can be generated by dif- ferent genetic mechanisms and/or activity-dependent mechanisms. thus, similar features of organization that have independently arisen in different lineages may not have similar underpinnings. examination of variability at multiple levels of organization indi- cates that although genes are not directly related to a specific be- havior, they covary with aspects of body and brain organization, which in turn covary with the targets of selection (fig. ). for ex- ample, the wing of a bat is constructed in development through complex interactions between genes and morphogens. slight var- iations in the amount, location, and timing of these factors can generate phenotypic diversity within a population. the presence of the highly derived wing with its array of specialized touch domes covaries with both the size of the forelimb representation and neural response properties in s . together such morphological and corti- cal specializations are critical for detecting and processing inputs that provide motor cortex with information necessary to produce fine muscle control during self-propelled flight. it is the resulting morphology and behavior, the efficiency with which a bat navigates, captures, and consumes insects using a wing of a given size, shape, tensor properties, and receptor distribution, which are the targets of selection. in addition there are genetic regulatory networks in the neo- cortex that are responsible for providing the scaffold of organi- zation that includes a constellation of cortical fields and their connectional relationships that all mammals share. these net- works can vary to produce phenotypic change in cortical field size, relative location, and connectivity within individuals in a population. this in turn generates changes in sensory mediated behaviors, and as in the example above, it is behavior, not genes or features of cortical organization, that are the targets of se- lection (fig. ). given this complex, multilayered relationship between genes, brains, bodies, the environment, and the targets of selection, the dialect of the current scientific culture, which proposes to study “the gene” for autism, language, memory, or any other class of complex behaviors, is inaccurate and certainly misleading. although variability is the cornerstone of evolution, it is dif- ficult to find studies that specifically examine and quantify nat- urally occurring variability in any aspect of neural organization. as the title indicates, such variability is unwelcome in most studies. we strive to underscore common features or the same- 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( ) aberrant retinal projections in congenitally deaf mice: how are phenotypic characteristics specified in development and evolution? anat rec a discov mol cell evol biol : – . . li y, fitzpatrick d, white le ( ) the development of direction selectivity in ferret visual cortex requires early visual experience. nat neurosci : – . . zhang li, bao s, merzenich mm ( ) persistent and specific influences of early acoustic environments on primary auditory cortex. nat neurosci : – . | www.pnas.org/cgi/doi/ . /pnas. krubitzer and seelke d o w n lo a d e d a t c a rn e g ie m e llo n u n iv e rs ity o n a p ri l , www.pnas.org/cgi/doi/ . /pnas. © koninklijke brill nv, leiden, | doi: . / - middle east journal of culture and communication ( ) – mejcc brill.com/mjcc ‘what is a beautiful body?’ late ottoman ‘sportsman’ photographs and new notions of male corporeal beauty* murat c. yıldız university of michigan, ann arbor, department of history and armenian studies program, usa mcyildiz@umich.edu abstract this article examines the emergence and spread of the ‘sportsman’ genre of ottoman photography in late-nineteenth and early-twentieth-century istanbul. the ‘sportsman photograph’ depicted young men posing shirtless or wearing tight-fitting athletic attire, flexing their muscles and exhibiting their bodies. these images were embedded in a wider set of athletic and leisure activities and constituted novel social and photo- graphic practices. by tracing the deployment of ‘sportsman’ photographs in sports clubs and the press, i argue that they cemented homosocial bonds, normalized and popular- ized new notions of masculinity, confessionalized the male body and reconfigured the ways in which ottoman muslims, christians and jews performed and conveyed their commitment to middle-class notions of masculinity and the self. keywords body – masculinity – ottoman – middle east – sports * research for this article was generously supported by grants from fulbright, the american research institute in turkey and the ucla center for jewish studies. i want to thank lucie ryzova for her insights and suggestions, and ziad abu-rish, arash davari, ahmet ersoy, james gelvin, lynn hunt, susan slyomovics, and the two anonymous reviewers for their comments and feedback. my gratitude goes to prof. ethem tolga, Çağlar Şavkay, dino belalilis and daniel ziffer for granting me permission to reproduce these images. i also want to thank münevver eminoğlu, tanaş belalilis, mehmet Şenol, duygu erözbek, filiz dağdeviren and yorgo demir. http://brill.com/mjcc mailto:mcyildiz@umich.edu ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – in , the ottoman turkish navy magazine ran an article in its regular sports column entitled ‘what is a beautiful body?’ (donanma mecmuası : ). in the opening paragraph, the author established that the article would ‘analyze beauty from the perspective of a physical training specialist’. such a view was ‘scientific’ and treated ‘health’ as corporeal beauty’s defining char- acteristic. ‘when speaking of beauty’, it asserted, ‘the first characteristic that should come to one’s mind is health’. published during world war i, the article echoes a broader conversation in late ottoman istanbul about the ideal male body. however, its emphasis on health diverged from other competing under- standings of physical beauty prevalent at the time. as the author put it, ‘the [true] meaning [of beauty] is not what is used among the people (beynelhalk) [emphasis mine]’ (donanma mecmuası : ). if health was not commonly understood as a beautiful body’s defining characteristic, then what was? what kinds of new notions of male beauty were emerging here? and what role did photography play in this transformation? during the late nineteenth and early twentieth centuries, ottoman muslim, christian and jewish citizens living in urban centers of the empire celebrated and promoted a new masculine corporeal aesthetic, and by consequence con- demned an older one. the defining characteristics of this new body were pro- portionality, a slim waist, defined biceps, a straight back and a broad and hair- less chest. the new look was deemed ‘beautiful’—because it was based on physical exercise as a personal effort, itself a new bourgeois value—and thus ‘civilized’. this late ottoman conception of a modern, urban masculinity, which echoed similar ideas and values in major urban centers around the world, stood in stark contrast to older ottoman views on the body and its relation- ship to social status. whereas a corpulent physique had historically exemplified financial prosperity, strength, virility and social status, with ottoman men even embracing the sobriquet ‘the fat one’ (şişman) (ginio : ; see also felek ), a plump belly now came to represent incompetence, lethargy and phys- ical inferiority. the development of this new conception of masculine beauty was indelibly shaped by the dissemination of the camera into the everyday lives of ottoman society and the democratization of photographic practices in general. the mushrooming of photography studios throughout istanbul, the invention of the majority of shirtless ‘sportsman’ photographs that i have encountered depict a hairless upper body. however, there are some exceptions. this suggests that although it was common for young men to use depilatories, during this period some continued to regard body hair as a marker of virility. for example, see zabel yessayan’s memoir ( : ) in which she describes her uncle khatchig’s ‘hairy chest’ as a sign of strength and virility. yıldız middle east journal of culture and communication ( ) – consumer-friendly snapshot photography, as well as greater access for men (and women) to have their pictures taken either in a studio or in their home resulted in the proliferation of diverse genres of portraiture during the late nineteenth and early twentieth centuries (cf. graham-brown ; erdogdu ; ersoy ; micklewright , ). among these vernacular genres was the ‘sportsman photograph’ that depicted young men posing shirtless or wear- ing tight-fitting athletic attire, flexing their muscles and exhibiting their bodies. the emergence and proliferation of the sportsman photograph was con- nected to the growing popularity of gymnastics and team sports, such as soccer and hockey, among upper- and middle-class young men of late-nineteenth and early-twentieth-century istanbul. muslims, christians and jews ‘worked out’ a shared understanding of sports and corporeal development in schools, volun- tary athletic associations, newly constructed urban spaces and the press (yıldız ). this new ‘civic’ culture centered around the belief that physical exercise represented an effective means to form robust young men, and by extension, modern communities (or millets), and a civilized empire. the sportsman genre of photography emerged in conjunction with the spread of sports clubs in various neighborhoods of the imperial capital during the reign of sultan abdülhamid ii ( – ). while young men developed their bodies by lifting weights, running and jumping, photography served as their medium of choice to record, display and communicate their masculine looks to each other. postcard-sized photographs were circulated as tokens of friendship among friends, colleagues and family during the hamidian era. this rather limited, personal circulation changed, however, after the young turk revolution in . the abolition of the hamidian regime’s censorship policies and the mushrooming of a robust multilingual print media played an impor- tant role in significantly broadening the circulation of the sportsman genre in public culture, further popularizing a particular vision of male corporeality as a defining feature of late ottoman urban masculinity. this essay discusses the sportsman genre of late ottoman photography as embedded in a wider set of athletic and leisure activities and constitutive of novel social and photographic practices. the deployment of these images— first through social networks and later through the press—cemented homoso- cial bonds, and normalized and popularized new notions of masculinity across confessional lines. but it also confessionalized the male body, and reconfig- ured the ways in which ottoman muslims, christians and jews performed and although here i focus exclusively on men, it should be noted that that photographs, drawings and caricatures of women exercising also appeared in the late ottoman press, as discussed in frierson ( ). ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – conveyed their commitment to middle-class notions of masculinity and the self. by tracing the intersection of the sportsman photograph and print media, this essay also proposes that images of the sportsman made visible the shift- ing boundaries of public propriety. circulated in the print media, these pho- tographs opened up debates about what constituted a ‘nude’ body. while phys- ical culture enthusiasts viewed these bare-chested images as embodiments of an ideal middle-class look and aesthetic, others were critical of men posing without their shirts. over a decade ago, wolf-dieter lemke, writing on photography in arab cities of the empire, implored scholars to treat photographs as neglected sources that could tell us a great deal about ‘an unprecedented interest in the indi- vidual’ during the period (lemke : ). many historians of the middle east have since drawn important insights into the cultural and social transfor- mations of the late ottoman era by taking photographs seriously as historical sources. stephen sheehi traces the emergence of a ‘bourgeois individualist sub- jectivity’ by examining the work and reception of local photographers in late nineteenth and early twentieth-century lebanon (sheehi : ). others treat photographs as a lens to observe changes in consumption and identity. nancy micklewright focuses on candid family snapshots in late ottoman istan- bul to discuss the nexus of domestic consumption and new bourgeois identities (micklewright ; ). this growing body of literature on middle east photography is moving away from an understanding of photographs as mere ‘illustrations’ of past events or ‘representations’ of past phenomena. it increasingly draws on insights of his- torians of vernacular photography who argue that photographs—especially vernacular photographs, such as commercial studio portraits, candid home snapshots, and others—should be understood as both material and social, or agentive, objects whose meaning does not reside merely ‘in the image’, but equally in the diverse modes of exchange and circulation in which they were embedded (see edwards for an extensive summary). i am thus primarily interested in the interplay between the historical development of the sports- man photograph as a visual genre, concomitant changes in print media and the the photographs discussed in this essay are representative of a larger body of understud- ied images that are either stored in the dusty archives of sports clubs in istanbul or scat- tered in private collections in turkey and around the world. they were procured in from the archives of the kurtuluş sports club (kurtuluş spor kulübü) and the galatasaray museum (galatasaray müzesi) in istanbul and daniel ziffer’s private collection in tel aviv. galatasaray’s archive has hundreds of photographs of club members and over twenty photo albums. hercules’ archive is more modest in scope: it has dozens of individual and group photographs and two photograph albums. yıldız middle east journal of culture and communication ( ) – production and dissemination of a new masculine corporeal aesthetic through these venues. tokens of friendship: ‘sportsman’ photographs in sports clubs sports clubs were one of the main spaces in which muslim, christian and jew- ish young men in late ottoman istanbul met to socialize and play sports. they were part of a growing trend of voluntary associations throughout the empire; these associations included educational, philanthropic, political, scientific and literary clubs (see, for instance, göçek ; watenpaugh ). sports clubs were exclusively spaces of male sociability and represented crucial sites where historically novel, young peer (generational) male subjectivities were formed, negotiated and performed. their popularity and social relevance reflected two related ideas among upper and middle-class circles of istanbul: first was the idea that exercise and a ‘beautiful body’ meant that one was a modern, cul- tivated and successful man; second, that a ‘sedentary life’ (oturucu bir hayat) had adverse effects on the bodies of ottoman citizens. according to selim sırrı, a turkish educator who went on to become the ottoman empire’s general inspector of physical training (terbiye-i bedeniye müfettiş-i umumisi), ‘one of the most important reasons for our illnesses is a sedentary life. we are always sitting in houses, government offices, workplaces, coffee houses, and casinos’ (sırrı : ). sırrı encouraged young men ‘to bring an end to this life of sitting’ by walking, doing gymnastics and exercising their bodies (sırrı : ). sports clubs served as the main spaces in which young men could put these ideas into practice. young men learned how to dress, talk and socialize through, and in between, exercising or playing; or, on other occasions, listening to lectures and reading. in these spaces, a new ottoman middle class was produced through the activities young men did together: playing games, reading books and mag- azines, or taking pictures. while much has been written on late ottoman associational life, scholars have either focused on how voluntary associations created novel forms of individual and group identities that foregrounded civic bonds and transcended ethno-religious divisions (watenpaugh ), or on the role of ethnically and religious homogenous organizations in the development of fissiparous movements during the late empire (göçek ). these approaches fail to account for the fact that many late ottoman voluntary associations were far from being ideologically pure spaces and fostered both ethno-religious and shared civic bonds. there were exceptions, however. for example, the jewish gymnastics club of constantinople (israelitische turnverein konstantinopel) created a women’s section in . this view of class draws insights from a growing body of literature that understands the ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – muslim, christian and jewish members of these clubs took photographs of themselves and of each other—a practice that had many purposes, motives and effects. dressing up in one’s best clothes and posing for the camera—whether for the professional photographer in a studio or among amateurs at home and during leisure activities—was an established practice in which young men asserted their status and professionalism as modern urban ottoman subjects. the sportsman photograph, as a distinct genre of vernacular portraiture in which young men posed either bare-chested or clad in athletic attire, cel- ebrated new imageries of male corporeal beauty, which was constructed as an integral part of this emerging ottoman bourgeois masculinity. such pho- tographs were used for private exchange and to strengthen homosocial bonds among friends, relatives and colleagues. some photographs may have ended up compiled in private albums (see ryzova ; and her essay in this volume). alternatively, club members also organized these images into club-specific photographic albums that were displayed in the reading rooms of their respec- tive clubs. these photographs and albums served as a visual history of the club, as records of the achievements of its members and the clubs as a corporate body, and as a means to record, perform and demonstrate the member’s suc- cess in achieving an ideal masculine look and identity. the first two images (figures and ) show the most popular posture as- sumed by club members in studios during this period: they stood bare-chested, and staring straight at the camera, flexing their muscles with their arms cros- sed. notably, the posture of both pictures is identical. as was common for this genre of photographic objects, one of these photographs has the member’s name written in the corner; the other does not. figure is of nikolas alibran- tis, a member of the hercules gymnastics association (gymnastikos syllogos eraklis). figure is of an unnamed member of the galatasaray physical train- ing club (galatasaray terbiye-i bedeniye kulübü). hercules and galatasaray were well-known exclusively male sports clubs that were associated with ethno-religious communities. hercules was a greek association, established in october in tatavla, a heavily greek populated area of istanbul (tataoulis gymnastikou syllogou hirakleous ). galata- middle class in the region as a cultural construct, not an empirical category. see, for example, watenpaugh ( ); di-capua ( ); jacob ( ); ryzova ( ). the archives of the hercules gymnastics club and the galatasaray physical training club in istanbul hold such ‘club’ albums. the hercules gymnastics association (gymnastikos syllogos eraklis) changed its greek name to the kurtuluş sports club (kurtuluş spor kulübü) during the early turkish republic when the name of the club’s neighborhood tatavla was also changed to kurtuluş (meaning yıldız middle east journal of culture and communication ( ) – figure nicolas alibrantis, a member of the hercules gymnastics association kurtuluş sports club archive saray was a predominantly turkish club that was located in the heart of the capital’s most europeanized district, pera, and on its most fashionable street, independence in turkish). both name changes were constitutive of broader turkification policies instituted during the early republic. ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – figure an unnamed member of the galatasaray physical training cub galatasaray museum archive album undated grand rue de pera. graduates of the imperial school (mekteb-i sultani), which was also known as the galatasaray lycée and was the most prestigious the distinction between being muslim and turkish became increasingly blurred in the imperial center during the second constitutional period. descriptions of galatasaray in the press and the club’s internal records refer to it as a turkish association. nevertheless, the club was neither religiously nor ethnically homogenous. for a discussion about the overlap of these identities and the reification of others, see gingeras ( ); kayalı ( ). yıldız middle east journal of culture and communication ( ) – figure members of the hercules gymnastics association kurtuluş sports club archive, undated state secondary school in the imperial domains, established galatasaray in october . the next two photographs (figures and ) show another common type of this genre, notably group photographs. figure shows five unnamed mem- bers of the hercules gymnastics association posing bare-chested, dressed in black shorts. each man is flexing both his upper and lower muscles, while facing the camera and posing. figure depicts three men with handlebar mus- taches dressed in identical white athletic apparel and surrounded by a balance beam, dumbbells and clubbells. the man sitting on top of the balance beam, l. shoenmass, is posing with his arms crossed, the man on the left, j. kornfeld, is leaning against the beam, with his right hand formed in a fist resting on his hip, and the man on the right, albert ziffer, is standing erect, while clenching his fists behind his back. the three men were members and administrators of the jewish gymnastics club of constantinople (israelitische turnverein kon- stantinopel), which german-speaking jews founded in pera in january . the differences between figures and go beyond the merely visual. shoen- mass, kornfeld and ziffer are posing in tight-fitting athletic attire, whereas the upper and lower bodies of the unnamed members of hercules are uncovered. these images are not unique; rather, they reflect the sartorial preferences that members of each club tended to choose when posing for their ‘sportsman’ photographs. both groups pictured here represent gymnasts; but the different social character and ethos of these clubs may provide a clue into these pref- erences. hercules, like galatasaray, was an exclusively male space. the jewish gymnastics club, however, had both male and female members. starting in , the club’s leadership promoted the idea that gymnastics and exercise were ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – figure members of the jewish gymnastics club of constantinople: starting from left to right, j. kornfeld, l. shoenmass, albert ziffer private archive of daniel ziffer not only mediums through which a new man was created; they were also fun, modern, leisure activities that all jews—men, women and children—should perform. the presence of female members in the jewish gymnastics club may have played a role in discouraging men from taking and sharing photographs of members posing bare-chested or in shorts. yıldız middle east journal of culture and communication ( ) – istanbul’s multilingual print media and the new public life of the semi-nude sportsman the circulation of vernacular photographs of semi-nude men was at first lim- ited to personal circles of friends, colleagues and members of voluntary associ- ations during the reign of sultan abdülhamid ii. this changed, however, after the young turk revolution in . the promulgation of the press law (mat- buat kanunu) in brought, to some degree, a relaxation of the hamidian regime’s strict censorship rules (yosmaoğlu ), and facilitated the establish- ment of a physical culture press (among other types of publications). this phys- ical culture press included daily newspapers and illustrated sports magazines published in different languages. four magazines were particularly notable (see figures and ): three were written in ottoman turkish, futbol (football), ter- biye ve oyun (education and game) and İdman (sports), and one was written in armenian, marmnamarz (physical training). all four emerged in the span of five years, between and . while some were short-lived and others irreg- ular, their popularity was indisputable. together, these publications exposed a wider array of istanbul’s denizens, not just members of athletic associations, to novel conceptions of male beauty. articles in these magazines focused on particular sports, scouting and other sport-related leisure activities, but also on wider issues of health, hygiene and lifestyle. written by educators, leading members and administrators of sports clubs, doctors and government officials, they insisted on the idea that young men should cultivate a well-defined, robust figure by regularly performing physical exercise in schools, in the gymnasium, and at the sports club, in order ‘to improve and take care of the body’ (marmnamarz c: ). they provided readers with ample guidelines and illustrations—in text and image—on how such an ideal body should look: it should be ‘proportionate’ (tenasüp) and ‘ele- gant’ (zarafet). an elegant body, according to terbiye ve oyun, was comprised of ‘beauty [and] proportion in posture and movement’ (sırrı : ). these ideas and debates appeared alongside images of semi-nude young men flexing their muscles. through this juxtaposition of images and text, editors established a firm connection between the physical shape of an ideal male body and broader modern middle-class values. futbol was established in october and was limited to seven issues, published irregu- larly. marmnamarz was founded in february as an illustrated monthly publication. in , it started publishing on a biweekly basis, and maintained this until december . terbiye ve oyun was published biweekly for a year, from august until august . İdman published thirty-one issues from may until may . ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – figure front page of one of istanbul’s multilingual sports magazines futbol, november yıldız middle east journal of culture and communication ( ) – figure front page of one of istanbul’s multilingual sports magazines marmnamarz, february ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – figure advertisement for fortin pills that combat fatigue. surrounding the image of the muscular sportsman are the words ‘strength, health and youth’ (kuvvet, sıhhat, gençlik). i̇kdam, september : these periodicals celebrated and encouraged what they considered to be ‘worthwhile’ and ‘meaningful’ corporeal concerns for the expanding urban middle class. marmnamarz chastised men and women for their superficial con- cern with ‘exterior beauty’. according to an article entitled ‘the beauty com- petition’ (martsum marmnagan keghetsutyan), very few people paid heed ‘to bodily care … and comprehend [the importance of] physical beauty’ (marm- namarz e: ). by condemning frivolous concerns with one’s appearance, such as wearing the latest fashion, marmnamarz was not privileging the inter- nal over the external: both were supposed to work in tandem. personal effort and exercise were middle-class masculine values that enabled men to con- struct a well-proportioned, beautiful body, and vice versa: a beautiful body was a sign of the values within. this line of argumentation stood in contrast to that found in other types of publications, which offered quicker approaches through consumption. for example, istanbul’s multilingual daily press is replete with advertisements for pills (figure ) that promised to provide men with vigor and muscle. physical culture journals were extremely suspicious of these mirac- for example, see sabah’s advertisement for furtin pills ( march : ). furtin pills were yıldız middle east journal of culture and communication ( ) – figure photograph of dad dadian, winner of the ‘beauty competition’ marmnamarz, november : ulous health potions. they posited that developing and appreciating a well- proportioned, beautiful body, was a prize that emerged not from consumption, but from effort, and ‘worthwhile’ leisure activity, notably sports. one of the many miraculous health potions that promised men the ability to develop a robust, virile body through consumption of these potions. together, they constituted an emerging commercial field that targeted middle-class residents of istanbul and other urban centers of the ottoman empire as their primary consumer. ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – journals soon created entire sections for photographs of semi-nude young men, run as regular features. İdman’s section was entitled ‘the exhibition of robust bodies’ (sağlam vücutlar meşheri), and was described by the journal’s editor as a space in which readers could ‘look at the “servants of the body and health” (vücut ve sağlamlık fukaraları)’ (İdman : ). similarly, the editor of the armenian magazine marmnamarz, shavarsh chrissian, regularly pub- lished pictures of young men and encouraged readers to admire and emulate these examples. the portrait photographs published in İdman and marmna- marz also included captions which reveal the ethno-religious identity of the robust bodies. the image below of krikor hagopian (figure ), for example, is collated with a description that establishes that he and his brother levon hagopian are among the ‘few armenian youth who take care of their bodies … [and] glorify the armenian name (hay anuně) through their bodies, will, and muscle’ (caption on image in marmnamarz april : ). photography served here as one of the most important tools of popularizing the physical culture press; photography served to record, promote and normalize a distinct male corporeal aesthetic. by regularly publishing images of sportsmen, editors also promoted photographic practices, as scores of young male readers wanted to own and share their own pictures to prove that they belonged to this new mas- culine ideal. but how ‘civic’ was this new masculine ideal? on one level, this new bour- geois ideal of corporeal beauty and its underlying modern urban values were shared, admired and adhered to by young middle-class ottoman men of diverse religious and linguistic backgrounds (and indeed, this masculinity had a global dimension) who aspired to this modernity. on another level, these venues in which young men cultivated this new ideal—associations, clubs and the press—remained firmly divided along confessional lines. thus, these spaces might have shared an ideal, but they also cultivated an exclusive ethno- religious identity among their readers and patrons, who were identified and addressed as belonging to a distinct community. for example, ottoman turk- ish sports periodicals, like İdman, juxtaposed discussions about ‘the turkish generation’ and ‘our athletes’, and used the first person plural ‘we’ and ‘turks’ interchangeably (İdman : ; İdman : ). similarly, marmnamarz the use of the word fukara, which literally means ‘poor men’, in the section’s caption is significant because of its connection to islam. muslims have historically used the term fukara (sing. fakir) when referring to mendicants and sufis as servants of god (green : ). İdman’s use of fukara also conveyed the meaning of servant, but challenged the traditional sufi understanding by replacing god with the body and health. thus, service to the body and health was compared to service to god. yıldız middle east journal of culture and communication ( ) – figure photograph illustrating the strong, robust bodies of readers marmnamarz, april : oscillated between using ‘armenian youth’ and ‘our youth’ (marmnamarz d: ; marmnamarz : ). the sportsman photographs circulating in the phys- ical culture press thus not only made new notions of masculinity and corporeal beauty both desirable and normative, but they simultaneously presented this modern male body as a confessional one. ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – where did the photographs in late ottoman physical culture journals come from? they resemble the previously discussed (figures – ) vernacular pho- tographs that administrators and members of sports clubs had taken during the hamidian period. and this is not surprising, as they were essentially the same photographs of young middle-class men, members of athletic clubs or physi- cal culture aficionados whose private portraits the bourgeoning press used to bolster its own popularity and sales. editors encouraged readers to send their private ‘sportsman’ photographs to the journal to be printed. marmnamarz even organized a male beauty competition as a means by which the journal pro- moted a distinct look and encouraged readers to take ‘sportsman’ photographs (marmnamarz e: ). unsurprisingly, marmnamarz’s male beauty compe- tition also carried a didactic purpose, which the editors did not fail to stress: the cultivation of robust, beautiful and healthy armenian bodies was not just a moral endeavor but also a social duty that young men and the broader com- munity alike needed to embrace. but while there is a clear generic continuity with the earlier photographs, there is also—in their incarnations as photographs reprinted on the pages of the press—greater variety, which mirrors the fact that the ‘archive’, so to speak, becomes larger once we are allowed to see a much larger pool of this vernacular genre. the majority of these portraits capture the upper body of shirtless, well-defined young men gazing directly at the camera, sporting short haircuts and moustaches, flexing their muscles and revealing hairless chests. but the four images below in figure , which were featured in İdman’s section entitled ‘the exhibition of robust bodies’, reveal a wider variety of postures. celal is shown glancing over his right shoulder while clenching his hands in front of his body; muhtar is facing the camera with arms akimbo; fuat is tightly crossing his arms and standing at a three quarter angle; and nedim is standing diagonally while gazing over his right shoulder and clasping his hands behind his back. while generically similar, each image is also unique and accentuates different parts of the body, thus inadvertently or consciously stressing the individuality of all four turkish men. nude, or not nude? men wishing to compete in marmnamarz’s beauty competition were asked to ‘take an appropriate nude picture of themselves and provide their age, height, weight, profession, as well as the measurements of their chest, waist, thighs, neck, ankles and mail it to the journal (marmnamarz a: ). the major- ity of the contestants were immediately disqualified, however, because their yıldız middle east journal of culture and communication ( ) – figure photograph illustrating the strong, robust bodies of readers i̇dman’s section entitled ‘the exhibition of robust bodies’, i̇dman, january : ‘what is a beautiful body?’ middle east journal of culture and communication ( ) – photographs only showed their upper bodies; in order to participate in the competition, participants needed to send full body photographs (marmna- marz b: ). the fact that the majority of the contestants sent photographs of their upper bodies—despite the journal’s explicit pleas—suggests that the vast majority of readers did not feel comfortable exposing the lower part of their bodies (especially their thighs) to strangers. nevertheless, one contes- tant, dad dadian, assiduously followed marmnamarz’s instructions and sent a full body photograph (figure ). as a result, marmnamarz crowned dadian the champion of the competition and presented him with a prize for the ‘beauty of his body’. marmnamarz also made sure to praise him ‘for not seeing anything wrong in showing his nude (merg) photo and not being afraid of public opinion’ (marmnamarz f.: ). dadian’s willingness to send his full body photograph to the magazine, despite possible public censure, suggests that not all ottomans were as enthu- siastic about seeing pictures of ‘nude’ young men being circulated in the press. an article entitled ‘nudity’ (mergutyune) published in marmnamarz explains that nudity was a polarizing issue for armenians, and possibly other ottoman citizens. according to marmnamarz, many believed that nudity was ‘immoral’ and would ‘scandalize’ humanity (“m.b.” : ). marmnamarz challenged this position by retorting that our ‘male and female ancestors’, who walked around naked, were not immoral. instead, marmnamarz treated the human body as inherently pure and something that should be celebrated, and even treated as a spectacle: things that are considered impure and ugly should be covered and con- demned by trial permanently, but the human body is not impure … nudity in marmnamarz should be considered art and compared to statues. men should marvel over beautiful bodies. marmnamarz, february : , emphasis mine this quote serves as one of the most lucid textual celebrations of, and jus- tifications for, the public display of the semi-nude male body in this period. it also implicitly challenges the differences between showing images among friends and in public by encouraging readers (men in particular) to ‘mar- vel over beautiful bodies’, irrespective of the context. ‘nudity’, it should be stressed, remained a fluid term that meant something different to different audiences. ottoman writers and editors of the physical culture press used the term ‘nude’ to describe varied degrees of uncovered chests, legs and thighs, but never to refer to the phallus. in this particular context, photographs of semi- nude men were not considered provocative, on the contrary, they were visual yıldız middle east journal of culture and communication ( ) – proofs of healthy bodies that could only belong to moral and virtuous young men. while the intentions of the editors might have been clear, how istanbul’s expanding public read these photographs is not. the circulation of the sports- man image through young male peer networks, often gravitating around the club, and later, in the press, suggests that young men who frequented these spaces and read these publications were not opposed to seeing an image of a nude and/or semi-nude man. however, private networks on the one hand, and popular magazines on the other, were not the same thing. marmnamarz’s insis- tence that both exhibiting and gazing at the nude body was entirely morally jus- tifiable implies that many readers in late ottoman istanbul thought otherwise. portrait photographs of young men posing shirtless or wearing tight-fitting athletic attire demonstrate that a proportionate, muscular, broad-chested, and hairless upper body in late ottoman istanbul represented the embodiment of masculine physical beauty and modern bourgeois values alike. young armeni- ans, turks, greeks and jews all celebrated, promoted and indulged in the pro- duction of novel corporeal aesthetics as a central component of late ottoman urban masculinity. these beautiful modern bodies, however, also remained firmly confessionalized. images of young turkish and armenian men exhibit- ing their robust physiques were collated with discussions in periodicals about how gymnastics and team sports served as the ideal means by which turks and armenians could strengthen their race and rejuvenate their respective com- munities. thus, editors of physical culture magazines treated images of ideal male physiques as representations of a shared notion of beauty, as well as indi- cations of the development of exclusive ethno-religious communities. these novel bourgeois bodies were thus at once ‘global’, ‘national’ and ‘confessional’. references di-capua, yoav ( ). common skies divided horizons: aviation, class and moder- nity in early twentieth century egypt. journal of social history ( ): – . donanma mecmuası ( ). 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( ). chasing the written word: press censorship in the ottoman empire, – . turkish studies association journal : – . the multicultural evolution of beauty in facial surgery braz j otorhinolaryngol. ; ( ): --- www.bjorl.org brazilian journal of otorhinolaryngology editorial the multicultural evolution of beauty in facial surgery� c c m b t a t r i a o h t e e a s a a c i p a c l p a r n a l a f n changes of aging as a decrease in fertility. the fourth and a evolução multicultural da beleza na the concept of facial beauty has been defined in a variety of ways dating back to ancient times, and while the defini- tion continues to develop, it has become clear that beauty crosses ethnic boundaries and has a significant cultural and economic impact. subconsciously, beauty is perceived by humans as a sign of favorable genes and increased fer- tility, both of which play a role in mate selection. as a result, perceived attractive features that are subcon- sciously selected evolve much more quickly than other naturally selected characteristics. additionally, the beauti- ful are more likely to get better grades in school, to be hired for a job, to receive higher salaries, and to be viewed as nicer, smarter and healthier. while beauty was once stated to be ‘‘in the eye of the beholder’’, more recent studies have suggested that beauty is an objective, quantifiable quality. the ancient greeks began the quest for a universal standard of beauty and believed it was represented by the ‘‘golden ratio’’ also known as ‘‘phi,’’ which was thought to represent perfect harmony. --- in nature, the ratio appears in the spiral of seashells, in the growth rate of the human mandible, and in the dna antihelix. examples of its appli- cation include egyptian art and architecture, the fibonacci sequence, and geometric shapes such as the pentagon and decagon. many still believe that phi corresponds to facial beauty as well. however, others have found it to be inexact. for example, marquardt created an ‘‘ideal’’ facial standard based off of phi, and not only did it apply poorly to people of non-european/caucasian descent but it also masculinized caucasian women. the concept of beauty as a formula continued to evolve with the artists of the renaissance period. through da vinci and his contemporaries, the neoclassical ideals were largely based on phi. the art anatomists of the th and th � please cite this article as: cerrati ew, thomas jr. the multicul- tural evolution of beauty in facial surgery. braz j otorhinolaryngol. ; : --- . l a f http://dx.doi.org/ . /j.bjorl. . . - /© associação brasileira de otorrinolaringologia e cirurgia access article under the cc by license (http://creativecommons.org/lic irurgia facial enturies propagated these new standards into the edical field, which created a ‘‘universal’’ definition of eauty for the period. while these ideals continue today o have a strong influence on facial analysis and serve as guideline for surgical planning, research has shown that hese ideals still do not apply cross-culturally. despite the inability to universally quantify beauty, esearchers have found that there is a consensus on rat- ng attractiveness across sexual orientations, ethnic groups, nd ages. studies have shown that diverse populations agree n who is and is not attractive. additionally, even infants ave an innate preference toward attractive faces. cer- ain conceptions of facial beauty or attractiveness may be verlasting. in , bashour researched and challenged ach of the four concepts. he concluded that subjective ttractiveness comprises only a small percentage of per- onal preference over a much larger biological objective ssessment of attractiveness. the four concepts of facial beauty include symmetry, verageness, youthfulness, and sexual dimorphism. the first oncept of symmetry is believed to represent a high qual- ty of development. a symmetric face reflects a person’s henotypic and genetic condition giving him or her an dvantage in sexual competition. averageness, the second oncept, is informed by the darwinian theory that evo- utionary pressures function against the extremes of the opulation. as a result, humans innately appreciate that verageness represents genetic heterozygosity and a greater esistance to disease. the third concept is youthfulness. eonatal features, such as large eyes and a small nose, re believed to suggest desirable qualities of youthful live- iness, open-mindedness and affability. as a person ages nd demonstrates soft tissue descent, the face deviates rom the phi standard, resulting in a decrease in attractive- ess. in addition, the human brain interprets the physical ast concept of beauty is sexual dimorphism, which is defined s a phenotypic difference between males and females. for emales, increased estrogen leads to the development of cérvico-facial. published by elsevier editora ltda. this is an open enses/by/ . /). dx.doi.org/ . /j.bjorl. . . http://www.bjorl.org http://crossmark.crossref.org/dialog/?doi= . /j.bjorl. . . &domain=pdf dx.doi.org/ . /j.bjorl. . . http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / s r c a i a h c f p a r n a i t n o f p p i h e c r a w i s t a f a e i fi r t e g p g t i t i o f t c i s t m s c t r otolaryngology-head and neck surgery, chicago, usa econdary characteristics that suggest a fertile host and a eproductive advantage. these include a thin jaw, small hin, large widely spaced eyes, small nose, high cheekbones, nd plump lips. on the contrary, desirable physical features n men are those that signify high testosterone levels, such s prominent chins, square jaws, deep-set eyes, thin lips, eavy brows and abundant hair. , although attractiveness can be agreed upon cross- ulturally, each ethnicity has unique features that are actored into its definition of ‘‘averageness.’’ for the facial lastic surgeon, these unique features must be respected nd embraced in order to create a harmonious and elegant esult that meets the criteria of beauty and attractive- ess. as a result, the neoclassical ideals may not serve as ccurate guidelines in non-caucasian patients. specifically n rhinoplasty, distinct anatomic differences exist between he leptorrhine nose seen in caucasians, the platyrrhine ose seen in african and asian populations, and the mes- rrhine nose seen in latin american populations. patients requently want to preserve their cultural identity, so it is aramount that the surgeon clearly distinguishes these goals reoperatively. today’s typical facial plastic surgery practice is becoming ncreasingly multicultural. the globalized modern society as played a significant role in the perception of beauty. conomic mobility coupled with an increase in interracial ouples has blurred the lines of ethnic identity, and the esulting esthetically unique and beautiful outcomes do not llow patients to be characterized as fitting a narrow mold ith predictable desires. the classic principles of beauty ncluding phi, symmetry, averageness, youthfulness, and exual dimorphism can still be applied as guidelines, but he surgeon must incorporate a broader outlook on facial nalysis and surgical techniques. the importance of identi- ying patients’ ethnic identities cannot be underemphasized s patients may want to erase, preserve, modify, or even nhance those specific inherent traits. furthermore, cosmetic surgery continues to become ncreasingly desirable and socially acceptable. the ampli- ed attention and interest can be credited to its exposure in eality television, social media, and surgical documentaries. he increased demand and the rising population diversity nsure that each patient will present with a unique back- round and cosmetic objective. the surgeon should assist atients to arrive at a goal that is harmonious with their face editorial iving a timeless, attractive result rather than be swayed by he development of a fashion trend. the proper guidance, nsight, and ethical control distinguish the surgeon from a echnician. more importantly, these qualities preserve the ntegrity of the field of facial plastic surgery. while facial modifications can have a tremendous impact n patients’ lives, the planned result should not venture too ar from the concepts of facial beauty that have defined he field since its creation. digital photography along with omputer imaging has aided with preoperative assessments n an effort to confirm the surgeon and the patient have the ame esthetic goals. technology will continue to improve o facilitate this initial conversation. as society evolves so ust our understanding of beauty along with our attempt to urgically define it. onflicts of interest he authors declare no conflicts of interest. eferences . weeks dm, thomas jr. beauty in a multicultural world. facial plast surg clin n am. ; : --- . . thomas jr, dixon tk. a global perspective of beauty in a multi- cultural world. jama facial plast surg. ; : --- . . prokopakis ep, vlastos im, picavet va, nolst trenite g, thomas jr, cingi c, et al. the golden ratio in facial symmetry. rhinology. ; : --- . . holland e. marquardt’s phi mask: pitfalls of relying on fashion models and the golden ratio to describe a beautiful face. aes- thetic plast surg. ; : --- . . bashour m. history and current concepts in the analysis of facial attractiveness. plast reconstr surg. ; : --- . eric w. cerrati a,∗, j. regan thomas b a university of illinois at chicago, department of otolaryngology-head and neck surgery, division of facial plastic & reconstructive surgery, chicago, usa b university of illinois at chicago, department of ∗ corresponding author. e-mail: ecerrati@gmail.com (e.w. cerrati). 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) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref mailto:ecerrati@gmail.com fashioning diaspora: beauty, femininity, and south asian american culture book review fashioning diaspora: beauty, femininity, and south asian american culture vanita reddy, temple university press, philadelphia, , pp., isbn: - - - - , $ . (hbk)/ isbn: - - - - , $ . (pbk) vanita reddy assembles and analyses a multi-format archive in fashioning diaspora: beauty, femininity, and south asian american culture. employing examples from south asian, especially indian, and south asian diasporic literary texts, movies and live performances, reddy provides insights on how beauty and fashion make space for new racialised subject formations, feminist and queer femininities in particular. resonating with queer south asian diaspora studies scholar gayatri gopinath’s work, these racialised subject formations are embodied subjectivities that create diasporic non-hegemonic sensibilities, desires, pleasures and affects. reddy deploys beauty and fashion as analytics, showing how discourses of beauty and its meanings operate as technologies of governance and animate and perform social relations. the author deploys affect as a tool to speak about epistemologies of beauty and what they do rather than referring us to what beauty is— aesthetic or sexual capital, commodities, style, aesthetic judgment or pleasure, etc.—as is often the case in sociological studies of beauty. and what beauty does, as affect, as discourse and as epistemology, reddy argues, is to recall material histories and ontologies of migration. reddy explains that both beauty and fashion often seem to be ideal technologies of the neo- liberal market, where individualism, self-care and fitness, and consumer citizenship reign. however, one of her major moves in fashioning diaspora is to reveal the power of the beauty and fashion economies, that is, economies naturalised as feminine and too often rendered apolitical or, at best, in her words, ‘juxtapolitical’. beauty and fashion, although marked as frivolous by normative, hegemonic discourses, in fact have strong and enduring consequences. in chapter , for example, reddy uses the novel jasmine by bharati mukherjee as a case study to show how beauty functions as an assemblage, ‘an aggregation marked by the radical difference, and even seeming incommensurability, of its components’ (p. ). beauty in this case is seen as both a promise and a limit for the protagonist, who aims at self-fashioning a notion of belonging in the diaspora as an undocumented immigrant in the united states; beauty serves as an agent and tool for recognition and inclusion in a manner that state-sanctioned citizenry does not grant undocumented people. jasmine’s interactions with the underground indian hair market in new york provide the novel’s reader a glimpse into a global market of indian female beauty. it becomes clear that in order for beauty to operate effectively, that is, in order for it to be legible and eligible for trade, it has to remain plain, as unmarked as possible, far from the fetish that commonly accompanies feminine, racialised beauty. if the processes of racialisation, gender exploitation, labour and migration become transparent for consumers, then beauty ceases to be profitable, and the immigrant’s access to belonging in the diaspora likewise evanesces. similarly, feminist review ( – ) � the feminist review collective. - / www.feminist-review.com the protagonist’s indianness and brown skin in the united states function as signifiers of lack of beauty. it is this ‘ugliness’ or plainness that nonetheless may give her access to citizenry. in this way, according to reddy, beauty becomes the instrument of territorialisation and deterritorialisation that diasporic subject formations necessitate to exist in the movement within, from and to ‘their’ nation. chapter of fashioning diaspora continues the book’s ode (as a recuperative text) to femininity by questioning dichotomous divides between cosmopolitanism and provincialism—as understood with regard to transnational mobility—and, by extension, between the public and the private. perceptions of ‘authentic’ femininity and ‘authentic’ nationality are troubled in reddy’s engagement with jhumpa lahiri’s feminist fiction writing, where beauty is commonly the attribute of non-indian and non-female bodies. these prosthetic femininities (p. ), as she calls them, referencing lauren berlant ( ), challenge the hegemonic mass-mediated notions of indian beauty that circulate within transnational market economies. incidentally, the author highlights, similar discourses have placed lahiri in the spotlight as an author in the first place. in this way, reddy nuances both the content of the short stories with which she engages, and the professional success and politics of the writer. in the later chapters of her book, reddy tackles other embodiments of beauty beyond the bodies and demeanors of characters, by examining the materiality and commodification of the bindi and the sari. following the author’s address on their fashionability and orientalist appropriations, the reader can trail the trope of ‘authenticity’ and its political deployments. in chapter , for example, the reader learns that in south asia the use of the bindi, whether made of powder or felt, usually signals the marital status of mostly hindu women; however, it has been appropriated in the west in events such as coachella and worn by artists like selena gomez in her music videos and performances. the artists whom reddy showcases, prema murthy, swati khurana and shailja patel, fight against these appropriations, enacting an awareness that the political problematic of the commodification of the bindi and the sari includes these products being better received on non-south asian, white bodies than on racialised ones. finally, fashioning diaspora’s reflections on the sari illustrate alternate modes of being. reddy analyses migritude, a live performance wherein queer poet and performance artist shailja patel asks the audience to bear witness to the affective costs we pay for the aesthetic pleasure of the sari, as it hangs from female bodies or from walls as indo-chic décor. patel uses the sari to invoke and represent histories of state violence. the artist thus deploys beauty to complicate identity-based politics such that attachments across difference become possible (i.e. between south asian and black african populations). following stuart hall ( [ ]), reddy narrates diaspora as a practice: diaspora is not a collection of individuals in a fixed or reified abroad, away from an also naturalised home nation, but a process where meanings are fabricated and connections and collaborations emerge (p. ). through the audience’s participation in the performance, and through the deployment of the sari as a relational object of beauty—different drapings of the sari call attention to alternate femininities, especially those varying by class (labour) or sexuality—new forms of non-heteronormative sociality, intimacies and belonging become possible. i look forward to further investigations on the intersections of masculinity and beauty in a future project or as a response from other scholars. likewise, incorporation of discourses of monstrosity, disability and humanity more broadly could add to reddy’s discussions of plainness and ugliness in their framing of book review feminist review beauty and fashion. nevertheless, fashioning diaspora is already a wonderful contribution to the scholarship within transnational feminisms. most importantly, beauty’s operations across borders—as a practice rather than an object or property—become an instrument to interrogate globalism, empire and the nation-state, as well as the gendered, racialised and sexualised processes these entail. placing scholars like gayatri gopinath, jasbir puar, lauren berlant and thuy linh nguyen tu in conversation with one another, reddy’s book intervenes in the fields of diaspora and postcolonial studies, critical fashion studies, south asian and asian american studies, gender studies (through queer of colour critique), and cultural studies. references berlant, l., . the female complaint: the unfinished business of sentimentality in american culture. durham: duke university press. hall, s., [ ]. race, articulation, and societies structured in dominance. in h.a. baker, m. diawara and r.h. lindeborg, eds. black british cultural studies: a reader. chicago: university of chicago press, pp. – . daniela gutiérrez lópez indiana university bloomington this review was written as part of professor lessie jo frazier’s graduate seminar ‘transnational and global feminist theory and praxis’ at indiana university. doi: . /s - - - feminist review book review fashioning diaspora: beauty, femininity, and south asian american culture vanita reddy, temple university press, philadelphia, , pp., isbn: - - - - , $ . (hbk)/isbn: - - - - , $ . (pbk) references sleeping beauty: awakening urothelium from its slumber review sleeping beauty: awakening urothelium from its slumber zarine r. balsara , and xue li , department of urology, boston children’s hospital, harvard medical school, boston, massachusetts; and department of surgery, boston children’s hospital, harvard medical school, boston, massachusetts submitted june ; accepted in final form january balsara zr, li x. sleeping beauty: awakening urothelium from its slumber. am j physiol renal physiol : f –f , . first published january , ; doi: . /ajprenal. . .—the bladder urothelium is essentially quiescent but regenerates readily upon injury. the process of urothelial regeneration harkens back to the process of urothelial development whereby urothelial stem/progenitor cells must proliferate and terminally differentiate to establish all three urothelial layers. how the urothelium regulates the level of proliferation and the timing of differentiation to ensure the precise degree of regeneration is of significant interest in the field. without a carefully-orchestrated process, urothelial regeneration may be inadequate, thereby exposing the host to toxins or pathogens. alternatively, regeneration may be excessive, thereby setting the stage for tumor development. this review describes our current understanding of urothelial regeneration. the current controversies surrounding the identity and location of urothelial progenitor cells that mediate urothelial regeneration are discussed and evidence for each model is provided. we emphasize the factors that have been shown to be crucial for urothelial regeneration, including local growth factors that stimulate repair, and epithelial-mesenchymal cross talk, which ensures feedback regulation. also high- lighted is the emerging concept of epigenetic regulation of urothelial regeneration, which additionally fine tunes the process through transcriptional regulation of cell cycle genes and growth and differentiation factors. finally, we emphasize how several of these pathways and/or programs are often dysregulated during malignant transformation, further corroborating their importance in directing normal urothe- lial regeneration. together, evidence in the field suggests that any attempt to exploit regenerative programs for the purposes of enhanced urothelial repair or replace- ment must take into account this delicate balance. urothelium; regeneration; progenitor cells; superficial cells; label retention; lineage tracing; epithelial-mesenchymal cross talk; epigenetics the urothelium is a unique epithelial surface that lines most of the genitourinary tract, including the renal pelvis, ureters, bladder, and proximal urethra. urothelium consists of multiple layers of epithelial cells that can change size and shape to accommodate fluctuating volumes of urine. this mucosal ep- ithelial surface also serves as a barrier to prevent absorption of toxic substances like acid and urea from the urine and to defend against entry of pathogens from the external environment ( ). implicit in this latter function is the ability of urothelium to “sense” and respond to the presence of pathogens within the genitourinary tract ( ). coordinating other cues from the external environment, such as chemical, thermal, and mechan- ical stimuli, requires an additional layer of sophistication ( ). besides direct expression of neuronal sensory receptors and ion channels on urothelial cells and their ability to release chemi- cals and neurotransmitters, afferent nerves also innervate the detrusor muscle and extend into the urothelial layer to help the bladder respond to external stimuli ( , , , , ). urothelium comprises three major cell types despite this wide range of functions, the urothelium has a relatively simple structure comprising three main cell types that are distinguished by their location, size, and expression of molecular markers. directly facing the luminal surface are large ( – �m in diameter) multinucleated hexagonal cells known as superficial or umbrella cells, which are principally responsible for the barrier function of the urothelium ( ). adjacent superficial cells are connected by tight junction pro- teins including claudin- and zona occludens (zo- ) that restrict exchange of ions and solutes between cells and between urine and blood ( , , ). superficial cells are covered by a crystalline lattice comprising four major uroplakin proteins that together form asymmetric unit membrane (aum) plaques. these plaques further restrict permeability to water, solutes, and toxins ( , , , ). superficial cells also contribute address for reprint requests and other correspondence: x. li, depts. of urology and surgery, boston children’s hospital, harvard medical school, longwood avenue, boston, ma (e-mail: sean.li@childrens.harvard. edu). am j physiol renal physiol : f –f , . first published january , ; doi: . /ajprenal. . . - x/ copyright © the american physiological society http://www.ajprenal.orgf downloaded from journals.physiology.org/journal/ajprenal at carnegie mellon univ ( . . . ) on april , . http://doi.org/ . /ajprenal. . . mailto:sean.li@childrens.harvard.edu mailto:sean.li@childrens.harvard.edu to the plasticity in urothelial cell surface area through a regulated process of endocytosis or exocytosis of discoidal/ fusiform-shaped vesicles (dfvs) containing uroplakins ( , , ). underlying the superficial cell layer is a layer of intermediate cells that are significantly smaller ( �m in diameter) than superficial cells. finally, along the basement membrane is a layer of basal cells. despite being the smallest population in size ( – �m in diameter), basal cells constitute the most abundant population of cells in adult urothelium. given the substantial size discrepancy between superficial and either basal or intermediate cells, it is no surprise that histo- logical analysis of whole-mount adult mouse bladders has revealed that one superficial cell spans the area of ~ under- lying intermediate/basal cells ( ). depending on the species, there can be as few as three discrete layers of urothelial cells in the mouse bladder and up to seven layers in the human bladder, with the additional layers contributed by interme- diate cells ( ). in addition to the size discrepancy among urothelial cells in the different layers, urothelial cells can also be distinguished by molecular differentiation markers, which begin to be ex- pressed at different stages of embryogenesis (fig. ). superfi- cial cells represent terminally differentiated cells and are the only cell layer in the bladder to express the low-molecular- weight cytokeratin (krt ) ( , , ). superficial cells also express several uroplakins (upk) but lack expression of the high-molecular-weight cytokeratin krt , the transcriptional factor p , and signaling molecule sonic hedgehog (shh) ( ). similar to superficial cells, most intermediate cells are upk� and krt �, but in contrast, intermediate cells also express p . diverging from superficial and intermediate cells, basal cells distinguish themselves by expression of high levels of krt and p but are negative for upk and krt . notably, despite the previous assumption that each of the three urothelial layers comprises a homogenous population of cells based on these five markers, our recent findings suggest that there is, in fact, significant urothelial cell heterogeneity. for example, variable levels of histone h lysine trimethylation (h k me ), an epigenetic modification often associated with gene silencing, are apparent among urothelial cells within the krt � basal as well as krt � intermediate and superficial cells ( a). in addition, ~ % of krt � basal cells also express krt . while the significance of urothelial cell heterogeneity remains to be determined, the krt �/krt � subpopulation of basal cells may play an important role in urothelial regeneration and tumorigenesis (to be discussed in subsequent sections) ( , , ). emerging techniques like single-cell rna sequencing (scrna-seq) may further stratify cells within each discrete layer and potentially identify functional differences among cells in each layer. normally quiescent urothelium rapidly regenerates in response to injury unlike the epithelium of the skin and intestine, mature urothelium has a very low mitotic index and turnover rate. pulse-labeling of unstimulated rat bladders with tritiated thy- midine revealed a labeling index of ~ . – . % ( , , , ) while uninjured mouse bladders had an even lower labeling index of . % ( , ). similarly, bladder biopsies from normal human patients that were cultured with tritiated thymi- dine in vitro had a labeling index of . % ( ). based on these low labeling indexes, turnover rates of quiescent rodent urothe- lium have been estimated to be approximately once every days ( , ). the prevailing quiescence of the urothelium makes its ability to awaken rapidly in response to damage even more remarkable. within hours of chemical injury with cyclo- phosphamide (cpp) or protamine sulfate (ps) or biological insult with uropathogenic escherichia coli (upec), the urothe- lium begins to proliferate and initiate the process of regener- ation (fig. ) ( , , ). one can imagine that urothelial regeneration needs to be carefully controlled. incomplete re- generation results in potential breaches in barrier function (fig. ) whereby toxic substances or pathogens in the urine can gain access to the bloodstream, stimulate local tissue inflammation, and/or depolarize afferent nerve fibers. in fact, this last process has been hypothesized as being a potential cause of bladder pain syndrome or interstitial cystitis ( , , ). conversely, unrestrained regeneration can lead to urothelial hyperplasia and possible malignant transformation (fig. ). an understanding of the molecular mechanisms responsible for maintaining the delicate balance between urothelial quiescence and regenera- tion is critical for devising new clinical strategies to prevent or treat diseases of the urothelium. given the priority of maintaining a protective barrier, it is not surprising that one of the first steps in urothelial regener- sc ic bc (shh- p - upk+ krt - krt - krt +) (shh+ p + upk+ krt - krt - krt -) (shh+ p + upk- krt + krt -/+ krt -) a b > /colorimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg coloracsimagedict << /tilewidth /tileheight /quality >> /jpeg colorimagedict << /tilewidth /tileheight /quality >> /antialiasgrayimages false /downsamplegrayimages true /grayimagedownsampletype /bicubic /grayimageresolution /grayimagedepth - /grayimagedownsamplethreshold . /encodegrayimages true /grayimagefilter /dctencode /autofiltergrayimages true /grayimageautofilterstrategy /jpeg /grayacsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /grayimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg grayacsimagedict << /tilewidth /tileheight /quality >> /jpeg grayimagedict << /tilewidth /tileheight /quality >> /antialiasmonoimages false /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputcondition () /pdfxregistryname (http://www.color.org?) /pdfxtrapped /false /description << /deu /enu >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice Годишњак Педагошког факултета у Врању, књига viii, / . Александар ПЕШИЋ Филозофски факултет Универзитет у Новом Саду ОДРЕЂЕЊЕ ЛЕПОГ У ПЛАТОНОВОЈ ФИЛОЗОФИЈИ Сажетак: У овом раду обрађују се „Хипија већи“, „Гозба“ и „Федар“ као три основна дијалога у којима је Платон изложио своју естетску теори- ју. У „Хипији већем“, након представљених десет дефиниција о лепоти, Пла- тон нам неће дати задовољавајући одговор на питање „Шта је лепо?“, већ ћемо добити одговор на питање „Шта није лепо?“ Али Платон нам посредно говори да би, када бисмо одредили шта је то лепота, то одређење морало носити универзално значење и бити применљиво на сваку појединачну ствар. На основу овога, Платон ће се позабавити питањем лепоте и у познијим дијалозима („Гозба“ и „Федар“) и показати да би за одређење лепоте било неопходно до танчина утврдити онтолошку теорију. У „Гозби“ ће дијалек- тичка метода служити као путоказ помоћу којег се сазнаје лепота и овај пут непосредно је повезан са љубављу, док ће се у Федру одредити значај еротске спознаје и описати склоп субјективних емоција које изазива лепота. Према Гадамеровој интерпретацији, показаће се да се лепо код Платона може посматрати „универзално онтолошки“ и да лепота има специјално место у битку. Након ових разматрања, увиђа се и да је поред алегоричног и дијалектичког Платоновог казивања лепоту тешко дефинисати. Кључне речи: Платон, естетика, лепо. Платон је, несумњиво, први филозоф у западноевропској мисли који покушава да изгради један целовити филозофски систем и од кога су остали писани трагови о том пројекту. Текстови су у форми дијалога, за које је Платон сматрао да донекле могу да замене живу реч. Има назнака да су дијалози писани како би се на неки начин филозофија популаризовала и била схватљива широком спектру јавности. Можемо само да наслутимо коју су вредност носила Платонова предавања у Ака- демији, будући да о њима није остао писани траг (више о овоме видети у: krämer, ). Вероватно би нам и биле отклоњене сумње о „неподудар- ности“ и „недоследности“ Платонове мисли. Оно што можемо да напоме- немо јесте и то да је Платон своје дијалоге писао у великом временском распону, па је он бележио своју мисао како се она мењала и сазревала. За сврхе овог рада ми ћемо посматрати постојање заједничке нити између раног Платоновог тумачења лепоте у дијалогу Хипија већи и зрелог схва- тања лепог из Гозбе и Федра. УДК . . . ( ) - прегледни научни рад - На почетку готово сваког Платоновог дијалога поставља се питање значења неког појма. На пример, Сократ ће на почетку дијалога поставити питање: „Ако тврдиш да си праведан човек, како би дефинисао правич- ност?“ Или ће можда питати особу која зна да је добра да дефинише доброту, или особу која је храбра или тврди да је храбра да дефинише хра- брост. Онда би Сократ настављао дијалог тако што би упитао особе да наведу примере за правичност, храброст, доброту, или би тражио аналоги- ју за исте ове термине. Овакво започињање разговора са младим Атињани- ма водило би у једну живу расправу. Ни Хипија већи, први целокупни спис који се у западноевропској мисли бави питањем лепоте, не почиње на дру- гачији начин. Дијалог се води између Сократа и Хипије, софисте који показује своје незнање пред питањем: „Шта је лепо?“ Међутим, видећемо да ни Сократ не наилази на задовољавајући одговор пред овим питањем. Постоје аутори који из овог дијалога изводе шест дефиниција лепог, међутим постоје и они који их своде на четири (guthrie, : - ) или две (Татаркијевич, ). Ми ћемо обратити пажњу на десет дефини- ција. Прве три и последња међу њима долазе од Хипије, док преосталих шест изјављује Сократ. Хипијине дефиниције више се односе на поједи- начно, док ће Сократове дефиниције задовољавати већи ниво општости. Прве три дефиниције које износи Хипија, јесу конвенционални одговори за оно што се у старој Грчкој сматрало лепотом. Другим речима, већина је на питање о лепоти одговарала на овај начин. Док ће Хипија покушати да одговори на питање: „Шта је лепо?“, Сократ ће у овом дијалогу покушати да утврди шта је лепота сама по себи. На Сократово питање „Шта је лепо?“, Хипија не даје конкретан одговор, већ почиње да набраја оно што он мисли да је лепо. То су само примери лепоте, а не и оно што лепота јесте. У Сократовим одговорима о лепоти, пак, показује се већа комплек- сност и ниво разумевања о томе шта је лепота у ствари. На крају дијалога свих шест поменутих дефиниција одбацује се. Да бисмо видели разлоге за ово, ми ћемо сваку од ових дефиниција размотрити понаособ. . Лепо је лепа девојка (Платон, : - ). Ово је прва Хипијева дефиниција. Одмах се види ниво наивности у овој дефиницији. Хипија уочава лепоту у појединачној ствари, у овом случају, у девојци. Уместо одговора на питање: „Шта је лепота?“, Хипија одговара на питање: „Шта је лепо?“ У овом, као и у наредним примерима, сви Хипијини примери релативни су. Другим речима, некоме је нешто лепо у одређеној ситуацији, а некоме није. Зато Сократ даје аргумент у коме су лепи кобила, лонац или лира. Значи, свака се ствар под одређеним околностима може посматрати као лепа. За одређење лепоте не могу се узимати нека спољна чулна карактеристика или конвенција. У овој првој дефиницији не јавља се само перспективистички поглед на лепоту, већ се уводи и рангирање лепоте. Прави се разлика између лепоте и ружноће, али се наводе и појединачна бића која су мање или више лепа. Отуда се Сократ позива на Хераклитов аргумент да је и „најлепши мајмун ружан у поређењу са најружнијим човеком, док је најлепши човек ружнији од богова...“ Међутим, као што смо горе напоменули, било би погрешно сма- трати да се ово рангирање узима као значајно, зато што се не посвећује пажња лепом, већ лепоти самој по себи. . Лепо је злато (Платон, : - ). Ово је други Хипијин одговор на питање о лепоти, након што је Сократ сугерисао да све лепе ствари морају да имају оно што их чини лепим. Другим речима, овде нам се наговештава да све лепе ствари морају да носе једну заједничку нит и да је та заједничка нит оно што их чини лепим. У овом случају, ми тражимо узрок лепоте. Хипија зато изјављује да све чему злато придолази постаје лепо и добро. На овом месту види се спој између лепоте и доброте. Сократ ипак износи аргумент како је Фидијина статуа Атине направљена од слоноваче и камена, тако да злато није главни елемент који све ствари чини лепим, па он помоћу релативизације обара и ову дефиницију лепоте. На овом месту Платон повезује идеју лепоте са исијавањем и сијањем. Лепота је сјај и блистање савршенства бића. Ову платонистичку тезу треба схватити дословно. Тезу да је идеја лепоте нај- сјајнија међу идејама Платон ће проширити у дијалогу Федар. Сама ова теза инспирисаће Гадамера да оправда свој херменеутички круг и своју филозофију. . Леп је пристојан и достојанствен живот, живот вредан живљења (Платон, : - ). За Хелене је била част живети пристојно, активно учествовати у политици, бити угледан, живети дуго, сахранити своје родитеље и бити сахрањен од својих потомака. Ову дефиницију засновану на самој тради- цији једне целокупне културе даје Хипија сматрајући је изузетно валид- ном, тезу коју је тешко оборити. Међутим, Сократ наводи пример о Ахилу, који је био поштовани јунак међу старим Грцима који би радије да умре млад, јер би у супротном његов живот био кукавичлук. Пред овим контра- аргументом се Хипија предаје и одбацује се и ова теза о лепоти. Са овом трећом дефиницијом се и завршава покушај да Хипија да одговор на пита- ње о лепоти. . Лепо је оно што је прикладно (оно што приличи) (Платон, : - ). Ово је теза коју износи Сократ. Наиме, Хипији се овај став чини одрживим и зато он даје пример да би лепа одећа учинила и ружног човека лепим. У том случају, ствар која нам се чини лепа морала би бити и истин- ски лепа. Са савременог гледишта ово се чини као сасвим прихватљиво и она нема исту тежину као што је имала и код старих Грка. Међутим, то није права лепота, већ привид. А ова категорија за Платона никако није могла да уђе у склоп о правој лепоти. Овде се јавља јасна дистинкција између „изгледати лепо“ и „бити леп“. „Бити леп“ би, по Платону, значило наћи право одређење оне исконске лепоте, тј. наћи архетип, саму идеју лепоте, док би „изгледати лепо“ значило неку врсту привида. Ова дистинк- ција повлачи и разлику између бића и привида. Штавише, ако прикладност чини ствари истински лепим, тад не би било могуће да се оно што је заиста лепо некоме учини ружним, као нпр. неки закони и обичаји. Прикладност или чини ствари заиста лепим – у ком случају не може бити оно што их чини привидно лепим, или их чини привидно лепим – у ком случају то не може бити лепо по себи, које желимо да дефинишемо. У том случају Сократ и одбацује ову тезу као могућу дефиницију лепоте. У овој дефиницији тако- ђе можемо да видимо да се из сфере појединачности, пребацујемо у сферу општости, тј. Хипија је покушавао да на појединачним примерима покаже шта је лепо, док ће Сократ покушати да лепоти да универзалнији карактер. . Лепо је оно што је корисно (Платон, : - ). На какву се корист овде мисли? На корист која се заснива на моћи. На један акт и могућност да се дела у складу с њим. Из овога произлази да је моћ лепа, а немоћ ружна. А где употребљавамо ту моћ? По Сократовом примеру – у политичком животу. Ова целокупна теза уплиће један морал- ни аспект иза себе, па из тога следи да се та иста моћ, то исто деловање може употребити и за ствари које су рђаве. . Сократ ће претходну дефиницију проширити, па ће рећи да је Лепо корисно са добром сврхом (Платон, : - ). За разлику од горње тезе, овде имамо јасно дефинисан циљ и јасно одређење у ком правцу наше чињење треба да се креће. . Лепо је пробитачно (Платон, : - ). Ако је лепо пробитачно, онда се поставља питање где се тачно идеја лепоте и идеја доброте разилазе, а где се спајају, и да ли на овом месту Платон поистовећује идеју лепоте са добротом? У овом случају, иако са одређеним опрезом, могли бисмо да одговоримо потврдно на ово питање. Наиме, за Платона су доброта и лепота саставни део идеје и иду руку под руку, тј. једно је немогуће без другог. Зашто онда Сократ одбацу- је и ову тезу? Због забуне која настаје између узрока и последице. Ако је лепота она што производи добро, онда би она била узрок добра. Али „иде- ја“ је оно што узрокује добро, а узрок и последица не могу бити исто. . Лепо је задовољство путем чула вида и слуха (Платон, : ). Дакле, из ове тезе видимо да се до лепоте стиже само путем задо- вољства чула вида и слуха. Али, шта је са осталим чулима укуса, мириса и љубавних наслада? Она се искључују. Сократ ће у наставку, помоћу ком- пликоване и не тако јасне аргументације, покушати да одбаци и ову тезу о лепоти. Ако прихватимо да је лепо оно што је пријатно и путем слуха и путем вида заједно, тад не следи да је лепо оно што је пријатно само путем слуха, или само путем вида. Ако је, пак, лепо оно што је пријатно само путем слуха, и ако је лепо оно што је пријатно само путем вида, тад не сле- ди да је лепо оно што је пријатно и путем слуха и путем вида. Из овога закључујемо да не постоји оно нешто заједничко из задовољства путем слуха и задовољства путем вида. . Лепо је пробитачно уживање (Платон, : - ). Ову тезу о лепоти Сократ ће одбацити из истог разлога због којег је одбацио и горенаведену тезу, у којој долази до мешања узрока и после- дице и „изједначења“ лепоте и доброте. . Лепо је бити способан лепо и добро говорити на суду, уверити слушаоце, однети награду, спасити себе, имање и пријатеље (Платон, : - ). Ову дефиницију о лепоти износи Хипија. Сократ се неће позаба- вити оповргавањем ове последње дефиниције, јер се у њој огледа Хипијин софистички став, а ако смо имало упознати са Платоновом филозофијом, знамо да је, између осталог, Платон презирао софисте и њихове игре речи- ма, преко којих су они долазили до личне користи. Појам лепог (καλον) и појам доброг заузимају посебно значајно место у Платоновим разматрањима, будући да заједно са појмом истине чине три највише вредности његове филозофије. То је његов такозвани „тријумвират идеја“. Ипак, питање о лепом испоставиће се као једно од тежих, па ће Платон и завршити дијалог реченицом: „Све лепо је тешко“. Након целог дијалога, као што смо видели, Платон нам не даје задовољавајући одговор на питање: „Шта је лепо?“ Тачније речено, ми добијамо одговор на питање: „Шта није лепо?“ Али Платон нам посредно говори да би, ради одређења шта је то лепота, то одређење морало да носи универзално значење и бити применљиво на сваку појединачну ствар. Поручује нам да лепо мора бити апсолутно лепо и није условљено. Такође нас упозорава да дефиниција лепоте мора да садржи и одређена логичка правила која је тешко омогућити (из тог разлога он и одбацује последњу дефиницију лепоте). На основу овога, Платон ће се позабавити питањем лепоте и у познијим дијалозима и показати да би за одређење лепоте било неопходно до танчина утврдити онтолошку теорију. Ако се осврнемо на само значење појма лепог (καλός), онда треба поменути неколико ствари: i) Превод који можемо наћи у Гозби и Федру, јесте термин „леп“. Међутим, овај термин има другачије значење у односу на оно што ми под лепим сматрамо данас. Код старих Грка, овај термин је означавао лепе младиће. Међутим, „леп“ може бити закон, као и наука. Ово видимо у Гозби, кад Диотима говори: „А после послова треба вод да га приведе к наукама да види лепоту наука. И кад већ гледа то обиље лепоте, неће се више задовољавати једном лепотом, као роб који негује лепоту каква деча- чића или човека или једнога јединога занимања, и тиме бити ништаван и ситничар; напротив, окренут према широком мору лепоте и посматрајући га, рађаће многе и лепе и величајне говоре и мисли у раскошној љубави према мудрости, док ту ојача и одрасте и сагледа једно једино онакво сазнање које се односи на овакву лепоту“ (Платон, : ). У једном случају, превод термина καλός, тј. „леп“, алудира на оно што стварно може да буде лепо, а у другом видимо да постоје и други термини који би καλός боље објаснили. Ми за законе и науку, из савремене перспективе, не бисмо рекли да су лепи. Најбољи начин за разумевање овог јесте да је термин καλός код старих Грка имао три главне употребе: ) У естетском смислу он се користио да би означио лепе особе, али такође и лица, одећу, оружје, зграде и друге предмете; ) У функционалном смислу, он би се могао превести као „ваљан“ или „користан“. Нпр. Овај нож је користан јер добро сече; ) „Племенит“, „частан“ јесу преводи који термину καλός дају морални тон. Тек када имамо у виду све ове три употребе, онда можемо сасвим јасно видети да се наша употреба речи „лепо“ разликује од Платоновог значења. ii) Други проблем настаје када покушамо да преведемо именицу κάλλος и придев καλός. Καλός има три значења, док у свом номиналном значењу κάλλος има само једно значење. Ово се види у Хипији већем, где Платон καλός и κάλλος користи наизменично. Наиме, термин κάλλος је прикладније превести као „фино“, „чисто“, док термин καλός преводимо као „лепо“. Ако пођемо од чињенице да је свако превођење са једног језика на други нека врста интерпретације, онда наилазимо на проблеме где се тер- минологија и њено значење мењају и поклапају. Тек онда кад имамо пот- пуно разумевање језика, увиђамо да су стари Грци налазили лепоту где је ми не видимо. Још се од времена Хомера јављала одређена сличност изме- ђу доброте, лепоте и истине. Знак да се лепота спаја са истином и пропор- цијом, Платон нам даје у Филебу: „...ако нам није пошло за руком да добро ухватимо у једној јединственој идеји, узели смо сво троје: лепоту, сразме- ру и истину, уз објашњење да нам то даје за право да их све заједно сма- трамо узроком свега онога што сачињава спој, а да је управо због тога што је то добро и сам спој такав какав је“ (Платон, : ). Колико год да нам се то чини тешким за разумевање, Платон ће повезати лепоту и добро- ту, иако не на сасвим јасан и разумљив начин. О Сократовом одређењу праведности у Ксенофонтовим Успоменама о Сократу каже се: „А казао је да је и праведност и сва остала врлина мудрост. Јер оно што је праведно и све што се ради врлином јесте лепо и добро. И који то знају ништа друго неће волети него то, а који не знају не могу тако да раде него, ако и поку- шавају, греше. Како се, дакле, и оно што је праведно и остало све што је лепо и добро оснива на врлини, очевидно је да је и праведност и свака остала врлина мудрост“ (Ксенофонт, : ). Као што видимо, Платон неће моћи да одлучи коју идеју да стави као водећу, већ ће се оне мешати, што је и један од водећих проблема у његовој онтологији. Мноштво идеја не може постојати другачије него сабирајући се и учествујући у оном јед- ном. Међутим, проблем настаје када покушамо да дефинишемо то једно. Зато ће га Платон често називати добротом, лепотом, мудрошћу, врлином. Са друге стране, Платон ће у Држави нагласити и онај субјективни моме- нат у сагледавању доброте и лепоте. Након што ће изнети учење да се душа састоји од умног, вољног и нагонског, Платон ће рећи да је једино здрава душа она у којој преовладава умни део. Једино је оваква душа пра- ведна. Али се ова праведност заснива на природи, савршенству и складу људске природе, па ће зато Платон изјавити: „Дакле, врлина је, како се чини, за душу нешто као здравље, лепота и снага; порок (какíа) је пак за душу нешто као болест, ружноћа и слабост“ (Платон, : ). Као што видимо, здравље и лепота стоје раме уз раме као врлине. Али здравље се у овом случају не узима само као физичка особина, већ и као једно психичко стање у коме се особа налази. Склад и хармонија прате здраву особу, па је и она у стању да „види“ лепоту. Гозба је настала пре више од два миленијума и ми морамо узети у обзир да се разматрања савременог човека и човека тадашњег доба разли- кују. Оно што је некад било прихватљиво, данас није, али то не значи да Платонове теорије треба одбацити као застареле или неупотребљиве. Одређену тежину у разумевању Гозбе носи чињеница да Платон у њој пре- плићу митско и поетично, рационално и емпиријско, идеално и чињенич- но. Али, ако се отплету ове мреже, достиже се један комплексан филозоф- ски систем који са собом носи велику вредност и јединствени начин мишљења. Поднаслов овог дела је: О љубави, међутим Платон ће пронаћи начин да баш ту лепоти да једну узвишену улогу. У Гозби, дијалектичка метода служи као путоказ којим се сазнаје лепота. Овај пут непосредно је повезан са љубављу јер је љубав одређена као жудња за лепотом и рађање у лепоти. Описано је шест степена лепоте. Први степен је жудња за лепим телима и у складу са тим рађају се и лепе мисли. Други степен обухвата обједињавање свих лепих тела која воде ка томе да се у души јавља жеља за стварањем уметничких дела. Трећи сте- пен је лепота душе и онај који ту лепоту види у себи и у другима може створити снажно пријатељство. Четврти степен је потреба душе да ради лепа дела која се из ње саме рађају. Пети степен прати разумевање лепоте у наукама. Шести и коначни степен обухвата љубав према мудрости и упознавање врховне лепоте. Из овог можемо закључити да овај пут или метода нужно подразумева учешће љубави и без тог заноса не може се доћи ни до чега вредног. Ови степени лепоте део су разговора који се одвија између Диотиме и Сократа. Који би онда био циљ оваквог напорног дијалектичког процеса? Платон нам то дочарава овим речима: „Ко је, дакле, довде упућен у тајне љубави, посматрајући лепоте тиме редом и правилом, тај ће, приближујући се крају љубавних тајни, наједаред угледа- ти нешто по својој природи чудесно лепо. То је баш оно, Сократе, ради чега су се и вршили сви пређашњи напори; нешто што је прво, вечно и што нити постаје нити пропада, … треба почети од многих појединих лепота и увек се успињати ради оне пралепоте, као да се ходи по степени- цама, од једнога тела двема телима, и од ова два свима лепим телима, и од лепих тела лепим пословима, и од лепих послова лепим сазнањима, и од сазнања доспети најзад до онога сазнања које није сазнање ни о чему дру- гом до о самој оној пралепоти, да се напослетку тако упозна суштина лепоте“ (Платон, : - ). Пре Платона, Питагора је утврдио да постоји „број, који је сва небеса“ и да он настаје од небеских тела која се окрећу у одређеној про- порцији, од чега и долазе симетрија и склад као основни закон космоса. Овде треба истаћи да бројеви немају само гносеолошко, већ и онтолошко својство. И човек, као природно, космичко биће, као микрокосмос, треба да својим властитим животом докаже да је микрокосмичко биће. Хармони- ја, склад, лепота и доброта у ствари су једно те исто. Они су супротности хаосу, нескладу, злу, ружноћи, које су стари Грци сматрали стањем које је претходило овом другом и које су сами богови променили. Стање хаоса одговара само варварским душама, необразованим људима, нехеленима. Лепота се из овог угла, по питагорејцима, третира као она која се налази у самој математици или неком математичком односу и покушава да се обја- сни помоћу мере и пропорције. Међутим, док се код питагорејаца јасно не исказује да ли су мера и пропорција неопходне за лепоту (што због фраг- мената који не говоре довољно о овој теми, што због наше немогућности да овај однос проверимо), код Платона је овај однос јасно изражен. Дија- лог Филеб богата је полазна тачка за разматрање лепоте у категоријама мере и пропорције. Зато Платон каже: „Сад нам се моћ доброг повукла у природу лепог; наиме мера и сразмера се дакако свуда јављају као лепота и врлина“ (Платон, : ). Овде се лепота исказује као апсолутна, у смислу да мера и пропорција не зависе од било кога или било чега. Доказ да Платон показује лепоту као меру и пропорцију налазимо и у Тимају: „Све што је добро лепо је а лепо не може бити несразмерно“ (Платон, : ). Врло често се у Тимају истиче лепота космоса и у овом дијало- гу налази се једна од важнијих Платонових дефиниција о лепоти. Оне су другачијег карактера и разликују се од екстатичног уздизања лепоте, као што то налазимо у Гозби. Међутим, и ова одређења лепоте у Тимају имају онтолошки карактер зато што бог, демијург, градитељ, ствара космос пре- ма узору на идеје, али је овде реч о лепоти која је остварена и видљива у космосу, а Платон је дефинише као закон постојања који потиче из доброг принципа, а очитава се у хармонији и мери. Овде се демијург јавља као „бог који се стално бави геометријом“, па је зато лепота дефинисана као један склад и хармонија геометријских тела. Овакво схватање лепоте, као што смо горе навели, блиско је питагорејском. Архетип лепоте код Платона представља једно од основних естет- ских принципа. Сама идеја лепоте искључује случајност и промену. Она је непроменљива и универзална, па је зато Платон тражи у суштини ствари, а не на њиховој површини. Платон сматра да гледати лепоту јесте исто што и сазнати истину. Заправо, сазнање има сврху, и то не само у откривању тајне природе, већ и у директном довођењу људске душе до узвишених облика и њеном обликовању у добром и лепом. Платон је лепоту сматрао објективно постојећом. За њега лепе ствари јесу лепе према свом учество- вању у идеји лепоте. Сама идеја лепоте не може да буде нека лепа ствар и стога не може да буде материјална: она мора да буде натчулна и нематери- јална. Овакве ставове Платон ће разрадити у Федру. Да би се пратио сам дијалог, неопходно је бити упознат са Плато- новом онтолошком теоријом и треба имати у виду дијалоге Хипију већег и Гозбу. Читајући Федра, имамо утисак да сва она питања о лепоти која нису добила одговор у Хипији и Гозби, овде коначно добијају своје разрешење. Сам поднаслов О лепоти говори нам која је основна нит којом ће се Пла- тон позабавити. Грубо речено, сам дијалог одређује значај еротске спозна- је и описује субјективне емоције које изазива лепота. Изнад небеског свода непролазним и вечним животом живе идеје. Оне су права и чиста бића, тј. чиста истинска бивства. Оне су истинско знање (епистеме) и не могу се докучити чулима, већ само умним разматра- њем. У тај свет се повремено уздиже Зевс и понекад га у обиласку тог све- та, уз богове, прате и душе демона и смртника. У цео овај свет могу се уздићи само одабране душе, где се, гледајући саме идеје, хране истином, праведношћу, добротом и мудрошћу. Зато ће Платон у Федру рећи следе- ће: „И то је живот богова, а за остале душе важи ово. Која бога најбоље сустиже и на њега се угледа, она се с главом возаревом уздигне у оностра- ну област, те се и она шеће унаоколо, али је узнемирују њени коњи, и она једва гледа оно што јесте. А друга се час узвије, а час опет спусти; а како су коњи силовити, она једно види, а друго не види. А и остале душе теже, додуше, на горње области и хитају за њима, али због слабе снаге заостају и обрћу се под површином, притискујући и гурајући једна другу и отимајући се да једна претекне другу. Зато настаје гужва и надметање, и зној се лије у највећој мери, и притом кривицом возара многе малаксају, а многе силу перја поломе; а све се, пошто су се много мука намучиле, враћају а да нису доспеле на гледање онога што јесте; и кад оду, хране се храном наслућива- ња. А она велика журба настаје зато да се види где је то поље истине, а и храна која доликује најбољем делу душе расте баш на ондашњој ливади, а њоме се храни и крило, којим се душа узвија“ (Платон, : ). Овај цитат нам је изузетно битан јер из њега можемо закључити неколико ства- ри: прво, Платон на овом месту показује изузетну поетичност која прати и цео дијалог. Овде је Платон на својеврстан сликовито-митски начин кази- вања успео најлепше да прикаже положаје душа на небу. Друго, показује да је пут до сазнања, до истинске лепоте, могућ, напоран и тежак и до њега могу стићи само појединци. У складу са тим, Платон ће дати и одређену типологију душа коју ће изнети даље у Федру. Он ће рећи да се, од свих душа, у првом реду налази она која је била најближа идеји лепоте и истине и такву душу имају или филозофи или пријатељи лепоте или службеници љубави. Друга је душа владара и она носи свој заметак у закону, трећа је душа привредника или онога ко уме управљати државом, четврта је душа гимнастичара или лекара, пета свештеника, шеста је душа песника или душа оног који се бави подражавањем, а затим следе душе занатлија, софиста и тирана (Платон, : ). Ова хијерархија показује нам Плато- нов негативан став према песницима, а такође нам говори и да су једини који могу да сагледају идеју лепоте нико други до љубитељи мудрости. Овај повлашћени положај заузимају само филозофи због тога што распо- лажу најузорнијим обликом душе, њеним умним делом, те су управо стога они и предодређени за највише сазнање. „А што се тиче лепоте, она је, као што рекосмо, сјала међу оним појавама: кад смо дошли овамо, прихватили смо је посредством нашег нај- оштријега чула као лепоту која најјаче сја. Вид нам се, наиме, појављује као најоштрије од телесних чула, али се њиме мудрост не види: јер она би нарочиту љубав изазивала у нама кад би нам давала онакву јасну прилику свога бића посредством вида, а исто тако и остало што је достојно љубави. А тако је само лепоти пало у део да је у исти мах и највидљивија и љубави најдостојнија“ (Платон, : ). Према овом цитату у Федру, али и пре- ма Гадамеровој интерпретацији, ми ћемо надаље у тексту показати да се лепо код Платона може посматрати „универзално онтолошки“ и да лепота има специјално место у битку. Горе смо показали да се употреба термина καλός, поред означавања лепих тела, грађевина итд, употребљава и у јед- ном функционалном и моралном смислу. Већ ће на основу тога Гадамер рећи да „...Све оно што не спада у неопходно за живот, већ у оно Како живота, све што се тиче εΰςήυ, све, дакле, што су Грци разумевали подπαιδεία, зове се καλον“ (Гадамер, : ). Другим речима, лепота је ту ради себе саме, њену вредност није потребно оправдавати јер се то види на први поглед. Она морална нота коју носи лепота нагониће Платона да уско повеже, али и често замењује, идеју доброг са идејом лепог. У том случају, ове две идеје стоје у потпуној равноправности. Гадамер ће постави- ти питање: „значи ли ово прекорачење сфере чулно видљивог у ‘интелиги- билно’ збиља диференцирање и виши степен лепоте лепог, и не значи ли само диференцирање и виши степен бивствујућег, које је лепо?“ (Гадамер, : ). Али Гадамер наставља: „Платон, очигледно, сматра да је телео- лошки поредак битка и поредак лепоте, да се лепота на подручју интелиги- билног појављује чистије и јасније него у видљивом, које мути протумерно и непотпуно“ (Гадамер, : ). У складу са овим горњим аргументима, Гадамер закључује да је, тако одређена, лепота „онтолошки универзална“. Можемо поменути и да је Гадамер нашао још једно оправдање Платонове лепоте као „онтолошки универзалне“, и то баш у цитату из Филеба који смо горе навели. На основу тога, Гадамер ће рећи да је у алегоричној функцији лепоте коју је Платон описао успео да пронађе онтолошки моме- нат структуре лепог, а самим тим и универзалну структуру самог битка. Очигледно је да се идеја лепоте приказује као независна и да је идеја лепо- те оно што сија у битку. Тиме, по Гадамеру, лепо добија најважнију онто- лошку функцију, а то је посредовање између идеје и појаве (види у: Гада- мер, : - ). Завршно разматрање Нема никакве сумње да је уметност стварање, да захтева велики напор уметника и његову личну мотивацију. Његов циљ је да из хаоса, небића, обликује нешто оригинално, да га претвори у конкретно биће. То конкретно биће било би склад савршених чулних елемената. Ови хармо- нични елементи налазе се у бићу као таквом, а лепоте има толико колико има и бића. Свако одсуство лепоте није ништа друго до недостатак бића. Бити леп значи бивствовати, а бивствовати значи бити леп. Ова таутоло- шка изјава има онтолошка својства, нарочито код Платона. Читава историја западноевропске естетике, још од почетака, још од Платона, сматра да уметник треба да подражава „идеално лепо“. Другим речима, пре човека и пре уметника постоји идеална лепота и из тога није ништа лакше него закључити да уметник треба да такву лепоту представи у делу. Међутим, данас се у уметничком делу тражи оригиналност, а не подражавање. Понекад нам се чини да је Платонова мисао далека од наше, да је оно што је он изложио у својим дијалозима страно и непојмљиво. Међу- тим, целокупна западна мисао наследила је Платонову доктрину и његови онтолошки, етички, естетски и политички ставови и до дан-данас могу се употребити или бар служити као инспирација у решавању неких кључних проблема. Иако је познато да је Платон бежао од „мртвог“ слова на папи- ру, неспорно је да је он био један од најбољих писаца. Живе расправе у облику дијалога показују огромну уметничку вредност његових дела. Посматрајући Платоново стваралаштво, његов начин писања и излагања његове филозофије, можемо се сложити да се уметничка вредност коју носе његови дијалози може мерити само ако се Платон узме у обзир као песник, мислилац и филозоф. Платонова филозофија пружа заиста богату лепезу мотива и тема каснијим филозофима уметности. Готово све касније естетике јесу на неки начин „варијације на Платонове теме“. Литература . guthrie, w.k.c. ( ). a history of greek philosophy, vol. iv, plato: the man and his dialogues, earlier period, cambridge university press, pp. - . . krämer, h. ( ). Платоново утемељење метафизике. Загреб: Деметра. . rosen, s. ( ). plato’s republic. london: yale university press. . Татаркијевич, В. ( ). Историја шест појмова. Београд: Нолит. . Гадамер, Х. Г. ( ). Истина и метода. Сарајево: Веселин Маслеша. . Ђурић, М. ( ). Историја хеленске етике. Београд: ЗУНС. . Ксенофонт. ( ). Успомене о Сократу, Београд: БИГЗ. . Платон. ( ). Тимај. Београд: Младост. . Платон. ( ). Хипија Већи, у: Дијалози. Београд: Графос. . Платон. ( ). Филеб. У: Менексен Филеб Критија. Београд: БИГЗ. . Платон. ( ). Држава. Београд: БИГЗ. . Платон. ( ). Федар. Београд: Народна књига – Алфа. . Платон. ( ). Гозба. Београд: Дерета. aleksandar pešić the definition of beautiful in plato’s philosophy summary: the paper discusses the hippias (major), symposium and pha- edrus as the tree main dialogues in which plato presented his aesthetic theory. in the hippias major, after ten presented definitions of beauty, plato will not give a satisfactory answer to the question „what is beauty?“ but we’ll get an answer to the question „what’s not beauty?“ but plato tells us indirectly to determine what is beauty. beauty must carry a universal meaning and is applicable to every single thing. based on this, plato will address the issue of beauty in the later dialogues (symposium and phaedrus) and show that the definition of beauty demands thoro- ughdetermination of the ontological theory. in the symposium, the dialectical met- hod will serve as a guideline by which one finds beauty and this path is directly related to love, while in the phaedrus one tries to determine the significance of ero- tic cognition and describe complex subjective emotions caused by beauty.according to gadamer's interpretation, beauty in plato can be considered as „universal onto- logical“ and that beauty has a special place in the being. after these considerations it is recognized, in spite of plato’s allegorical and dialectical narratives, that the beauty is hard to define. key words: plato, aesthetic, beauty. Примљено: . . . године. Одобрено за штампу: . . . године. in search of beauty : developing beautiful organizations citation for published version (apa): groot, de, s. a. 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https://research.tue.nl/en/publications/in-search-of-beauty--developing-beautiful-organizations( d a -bc - e -a - d f a ).html in search of beauty developing beautiful organizations steven adriaan de groot in search of beauty developing beautiful organizations steven de groot isbn: - - - - cover design: ursula rooijackers, utrecht picture cover: the analysis of beauty, hogarth ( ) print : printservice technische universiteit eindhoven, eindhoven copyright © s.a. de groot all rights reserved. with prior written permissions from the author* any part of this book may be reproduced by print, photocopy or any other means. via sdegroot@kultifa.nl a catalogue record is available from the eindhoven university of technology library in search of beauty developing beautiful organizations proefschrift ter verkrijging van de graad van doctor aan de technische universiteit eindhoven, op gezag van de rector magnificus prof.dr.ir. c.j. van duijn, voor een commissie aangewezen door het college voor promoties, in het openbaar te verdedigen op donderdag juli om : uur door steven adriaan de groot geboren te geldrop dit proefschrift is goedgekeurd door de promotiecommissie: voorzitter: prof.dr.ir a.c. brombacher e promotor: prof.dr.ir. m.c.d.p. weggeman copromotor: dr.ir. w. van der borgh leden: prof.dr.ir. j.e. van aken prof.dr. h.a. akkermans (tilburg university) prof.dr.l.i.a. de caluwé (vrije universiteit amsterdam) prof.dr. p.p.m. hekkert (tu delft) prof.dr.ir. c.c.m. hummels i acknowledgements ‘we have long neglected the aesthetic context of organizational behavior’ (guillén, ) wonder ‘wonder is the beginning of wisdom’, socrates argued long ago. and he is right, i can determine afterwards. questions were the motivation for this thesis. questions as results of combinations of experience, and especially my experience as a product designer and organizational researcher and consultant. it is pleasant to come across people in a process of wonder. first, there is the recognition of that wonder by professor mathieu weggeman. he also asked the question ‘can or may organizations also be beautiful?’. educated at the eindhoven design academy, with the obviousness that products should have both functional and aesthetic value, doing organization research and consultancy i noticed that this combination is not quite obvious in organizations. so i started this dissertation during my work at the iva institute at the university of tilburg this study. first organizations were being asked about beauty by using surveys. simultaneously, ten organizations during interviews showed me their associations with beauty and ugliness. but this was a fairly intuitive method of data collection of beauty in organizations. but there was recognition. i had grasped something. and it was time to address this project more seriously and structured. through a wandering at the university of humanist studies in utrecht i ´landed´ again in eindhoven this time at the technical university. recognition was converted into support. mathieu weggeman and joan van aken pledged their support to further research. wonder resulted in serious questions and research design, culminating in this dissertation. word of appreciation wonder was indeed only a beginning. thanks to many people this dissertation was established. first mathieu weggeman, thank you for your many rich contributions. you stimulated and helped me to explore the scientific challenge of organizational aesthetics as well as offered applications for practitioners in organizations. our discussions were informative and beautiful! then of course joan van aken, you emphasized and guarded the methodological lessons and strengthened me with your vast experiences with design science research (dsr). i will cherish our conversations at your place. ´me in the mountains’- and thereby stimulating aesthetic reflexivity - is definitely the purpose of life! thanks to michel van der borgh, my critical friend, who joined the team at a later stage. thanks to your unbiased and fresh look and your methodological knowledge, the manuscript is undoubtedly more concise and improved. i would like to thank my former colleague hans mariën (iva) who helped me with the quantitative data and checked my different analyses. i gratefully remind the inspiring e-mail contacts with professor helmut leder (freie universität berlin) and with professor rolf reber (university of bergen). finally, i am grateful to hundreds of people and dozens of organizations for their contribution by interviews, questionnaires and self-reports. this research leaned heavily on your cooperation and eventual empirical data. thank you all very much! thanks to bianca and frederieke of the secretary office of the item department for all your help. thanks to ine for checking and improving the english text. there remains thanks to my manager jeroen eijskoot of the dutch police, who during a few years offered me the opportunity to spend working hours on this thesis. i conclude this preface with a message to the beauty which surrounds me in daily life: friso, siebe, and jacqueline. experiencing beauty is perhaps the first goal of life. be receptive to the everyday beauty around you and share them with your loved ones. bunnik, april . ii iii table of contents part developing beautiful organizations ...................................... introduction .................................................................................................................... . motivation................................................................................................................................ . preliminary research questions ............................................................................................. . structure of this dissertation ................................................................................................. literature study ............................................................................................................ . organizational aesthetics ....................................................................................................... . aesthetics ............................................................................................................................... . organization design ............................................................................................................... . emotions in organizations & affective commitment ............................................................. . combining theories: an organizational aesthetics framework .............................................. design science research ................................................................................................ . design objectives ................................................................................................................... . rationale: research strategy & research design .................................................................... . sources of data ...................................................................................................................... . data collection and analysis ................................................................................................... empirical studies ............................................................................................................ . five empirical studies ............................................................................................................. . discussion............................................................................................................................... developing beautiful organizations .......................................................................... . context of design ................................................................................................................... . design causality...................................................................................................................... . design principles .................................................................................................................. . design interventions ............................................................................................................ . indications and contra-indications ...................................................................................... validation ...................................................................................................................... . validation of interventions .................................................................................................. . consequences for design ..................................................................................................... . suggestions for future validation ......................................................................................... reflection ...................................................................................................................... . reflections on the design process ....................................................................................... . reflections on the design ..................................................................................................... . relevance of the dissertation .............................................................................................. . suggestions for further research ......................................................................................... iv part theorizing beautiful organizations .................................... introduction ................................................................................................................. aesthetics ....................................................................................................................... . aesthetic theory ................................................................................................................... . aesthetic experience............................................................................................................ . aesthetic quality and properties.......................................................................................... . experiencing beauty ............................................................................................................. . aesthetic process ................................................................................................................. . aesthetic judgment .............................................................................................................. . conditions for aesthetic experiences .................................................................................. . aesthetic supervenience ...................................................................................................... . aesthetics in design disciplines ............................................................................................ . conclusions .......................................................................................................................... organizations and design ........................................................................................... . organization design ............................................................................................................. . changing perspectives on organizations and management ................................................ . job design and process design ............................................................................................. . professional organizations ................................................................................................... . aesthetic perspective on organizations ............................................................................... . conclusions .......................................................................................................................... emotions in organizations ......................................................................................... . affect at work ...................................................................................................................... . affective commitment ......................................................................................................... . conclusions .......................................................................................................................... conclusions ................................................................................................................... v references .............................................................................................................................. appendices .............................................................................................................................. appendix : aesthetic related terms used in organization literature ......................... appendix : data empirical study - interviews organizations................................. appendix : data empirical study - ideo-research ............................................................ appendix : correspondence respondents empirical study .......................................... appendix : overview characteristics of respondents empirical study .................... appendix : data empirical study - survey appreciation of oas ................................... appendix : data empirical study - factor analysis ......................................................... appendix : data empirical study - answers open-ended questions ........................... appendix : data canonical correlation analyses........................................................... appendix : data empirical study - results bel-book ..................................................... appendix : overview of mentioned oas ............................................................................. appendix : data empirical study - returning employees ............................................ appendix : first relation oas and revenues ..................................................................... appendix : correspondence empirical study ................................................................. appendix : data empirical study - teachers of elementary schools ....................... appendix : data empirical study - surgeons .................................................................. appendix : data empirical study - paes professionals correlations ....................... appendix : data empirical study - naes professionals correlations ...................... appendix : data empirical study - associations formal properties ........................ appendix : overview data professionals and general employees .............................. appendix : overview questions focus of organizational aesthetics ........................ appendix : invitation validation workshops ................................................................... appendix : description validation workshops ................................................................ appendix : data validation workshops ............................................................................. appendix : vocabulary organizational aesthetics ........................................................ summary ................................................................................................................................ dutch summary ..................................................................................................................... about the author ................................................................................................................. vi part developing beautiful organizations part | introduction introduction this dissertation explores the theory of aesthetics in organizations in practice. it describes what cause negative and positive aesthetic experiences (naes and paes) of employees in dutch professional organizations and the circumstances (organizational design) in which they take place. by having conducted five field-studies, the small amount of current literature on this topic has been validated and enriched. the study results in design principles for organizations in which positive aesthetic experiences will increase and in which negative aesthetic experiences will decrease in order to achieve a feeling of ´i am working in a beautiful organization´ by employees and to improve their affective commitment. these design principles are brought into operation into concrete design interventions which can be applied by managers, employees and consultants to beautify organizations. . motivation this paragraph describes the arguments for starting the study of organizational aesthetics. first, my personal motivation will be argued. second, the scientific and practical contribution of the role of aesthetics in work and organization design will be explained. personal motivation in i moved from utrecht to eindhoven to study product design at the design academy. i learned that products, besides functional value, have aesthetic value as well. after that i studied learning and instructional design and finished an mba-study and worked as a consultant and researcher (university of wageningen, lei; university of tilburg, iva) in the field of organizational development and knowledge management. and i wondered, stimulated by the eponymous best seller of peters and waterman, why organizations focus on functional aspects in particular and are only in search of excellence. do aesthetics not exist in working life and organizations, whereas aesthetics seem to play an important role in the daily life of people outside organizations? do employees have a need for aesthetic experiences? can organizations simultaneously ‘do good things in a good way’ (effective x efficiency) ‘do beautiful things in a beautiful way’ (beauty production x production beauty)? in other words, can the concept of beauty be transferred from the more tangible entity such as a product, person, animal, or service to the more intangible, tacit entity of organization? these questions or even fascinations were the main motivations for doing this research and made me decide to return to eindhoven. scientific relevance reflecting whether attention to organizational aesthetics makes sense for employees or might be a fruitful perspective for managers was initially commenced by four observations: the changing role of experiences like aesthetic experiences in people’s daily life; the attention of management for less rational but more irrational aspects in organizations such as spiritualism, passion and sense-making in the last decades to enhance well-being in organizations; as an elaboration of this second observation, initial ideas about organizational aesthetics as a new or complementary perspective on organizations and management are recorded in literature, but; these initial ideas in existing literature on organizational aesthetics do hardly describe any prescriptive or empirical research on this topic such as case studies. part | introduction the first observation is that aesthetics seem to play an important role in people’s daily life. following baumgarten, who introduced the term ‘aesthetic’ in , aesthetic means ‘perception by means of the senses’. people have aesthetic needs (alderfer, ; reiss and havercamp, ) and daily aesthetic experiences by demonstrating aesthetic response and judgment when their senses are stimulated (veryzer, ). people make choices for things like partners, friends, holydays, clothes, and interior and these also based on affective and aesthetic arguments, just because that ‘feels good’. we live in an increasing ‘aesthetization of the world’ leder et al. ( ) argued. the value of a person’s life – whether it was filled with interesting and meaningful events or whether it was a sequence of featureless and pointless ones – is determined more by the sum of experiences over time than by a sum of objective possessions or achievements. by this measure, aesthetic experiences are important indeed (csikszentmihalyi, ). ´they provide visceral, holistic, and greatly rewarding sensations that are ordinarily absent from pure cognitive activities´ baumgarten ( ) argues and aesthetic experiences also yield mental health and greater social well-being (dewey, ). so, talking about aesthetics, having aesthetic experiences and making aesthetic judgment seem to be quite natural in people’s daily life. but part of this daily life people also have their working life. and in general people who are part of the working population spend about thirty-six hours a week, two hundred days a year, and forty years in organizations, which are dominated by ‘rational rules’ of effectiveness and efficiency legitimated by the paradigm of ‘scientific management’ (taylor, ). when we agree that aesthetics is not limited to life outside organizations, what are people’s aesthetics needs, which aesthetic experiences do they have and on which stimuli are they based? the second observation made is that organizations slowly change to more human-centered and affordance based organizations (e.g. zammuto et al., ; hatchuel, ).gagliardi ( , p. ) argued that ‘the scientific revolution and the perfecting of the cognitive framework of the natural sciences achieved by newton divided his study of the primary qualities of the physical world – objective, universal and subject to the language of mathematics – from its secondary qualities, which are the object of subjective experiences, sensory and inexact.’ irrational aspects like passion, sense making, values, spirituality, personal development, and well-being in organizations were extensively researched and described the last two decades (e.g. bryan and joyce, ; zandee, ; hatchuel, ). sensible or aesthetic knowledge replaces or at least extends to scientific knowledge as consequence of the paradigm change of positivism to post-modernism (hatchuel, ). employees acquired labor rights and obtained a position in which their well-being and job satisfaction is asserted. both needs, well-being in people’s life as well in working life (job satisfaction), were extensively examined the last few decades. more recent research on well-being shows facets or dimensions like meaningful goals, personal growth, autonomy, value and self- acceptance relation with those which are discovered for working life like task significance, autonomy and task identity (see herzberg, ; hackman and oldham, ; reiner and zao, ). meyer and allen ( ) introduced the concept of affective commitment, which can be defined as ‘positive feelings of identification with, attachment to, and involvement in the work organization’ (meyer and allen, , p. ). affective commitment, often regarded alongside continuance commitment as one of the components of organization commitment, shows the strongest correlation with job performance, organizational citizenship behavior, role conflict and attendance and is the strongest and most consistent predictor of organizational outcomes like employee retention and performance. so, a growing attention in last few decades for human aspects in organizations can be determined, which could be a breeding ground for attention to aesthetic experiences of employees. the third observation welled up because of the growing amount of articles published about aesthetics in organizations. the field of organizational aesthetics initially was explored in the s´ part | introduction by sandelands and buckner ( ) strati, ramirez, gagliardi, guillet de monthoux, alvesson and berg ( ) and linstead, likewise stimulated by the growing attention of ´human´ issues in organizations like meaning, spiritually and human development at the end of the last century. and organizational aesthetics became part of the vocabulary of organizational discourse, strati ( ) argued. the missing of aesthetics in ‘ideas’ of truth, good, and beauty (habermas, ) or utilitas (functional), venustas (beauty, authenticities) and firmitas (construction and durability) seems to be distinguished in organizational design too. where in working life and in organizations are aesthetics hidden, knowing that environmental conditions are of paramount importance for the aesthetic experience (csikszentmihalyi, )? finally, the gaps in existing literature on organizational aesthetics are a major reason for doing further research on this topic. this gap concerns the translation from theory to practice. dominant in the earlier studies about aesthetics in organizations is the descriptive and deductive way of research. although these studies presume that employees have aesthetic experiences in their daily working life, there hardly has been done any prescriptive or empirical research on this topic, like case studies. the first contributions on organizational aesthetics can be largely characterized by a high theoretical level and are mainly located in the ideas stage. hardly any research has been done in practice in this new area of organization research. this dissertation exposed an extensive attempt to explore organizational aesthetics in practice. for example, the extent to which, and the kind of aesthetic experiences employees have, under what conditions and which effects is still unknown. how many experiences, by what stimuli, what kind of, the durations of the experiences and their impact haven’t been researched yet. also the relationship with the context in which they occur - the organization design- hasn’t been explored before. further, the role of aesthetics (aesthetic properties) in the design principles within the most design disciplines like architecture, product design and theatre is undeniably accepted except from organizational design. can we design and reform organizations by adapting design principles of other design disciplines? and secondly, existing literature on organizational aesthetics hardly position the topic in the context of existing theories about aesthetics, emotions in organizations and organization design with the ambition to develop a theory or framework for organizational aesthetics. practical relevance this dissertation not only aimed to increase the knowledge base of organizational aesthetics. this project also aspired to provide every day practice in organizations, ‘how to’ tools (a design protocol or design interventions) to initially realize more positive aesthetics experiences and to decrease negative aesthetics experiences of employees. and secondly, for those who need to have more benefit(s) of aesthetic experiences, this dissertation offers design principles which increase affective commitment of employees, resulting in more employee retention and better performance. and finally, those mentioned design principles for beautifying organizations provide a new and broader repertoire of design interventions for organization improvement and performance improvement. this insight is an unexpected result of the conducted validation workshops (see chapter ). generated knowledge and practices in which this knowledge is applied interact in two streams. these streams were labeled knowledge stream and practice stream (stam, ; van aken and andriessen, ). whereas the practice stream aims at solving specific problems in specific situations, the knowledge stream focuses on producing generalizable and transferable knowledge that can be used as solution concepts for solving similar problems in similar contexts (stam , ). the practical relevance of this dissertation therefore, was and is, to provide organizations and part | introduction consultants with the principles - by using generative knowledge - to add an aesthetic perspective to their daily operations and to increase positive aesthetic experiences which contribute to affective commitment of employees. this was partly encouraged by the research of schön. he argued that developed knowledge can be executed outside the immediate practice with the intention to improve the practitioner’s capacity for reflection in action (schön, ). schön considered the interplay between the designing architect and the particular situation as a dialogue, a reflective conversation. the designer is in a process of reframing a problematic situation, experimenting, evaluating and judging the outcome of the experiments. the dialogue is a dialogue between the designing agent and his or her intermediate solutions, the design situation (Östman, ). so, explicitly is chosen for instrumentalization of the theory of aesthetics in the context of work and organizations based on ‘pragmatist aesthetics’ initially supported by dewey ( ). this justification is argued in section . of part . . preliminary research questions in sum, there were several reasons for conducting this dissertation. in the third chapter about methodology, the initial research question and project objective are expressed by using the cars- logic (creating a research space), which is typical for design science research (van aken and andriessen, ). this logic starts with defining why a specific phenomenon or problem in practice is relevant to be examined. expressed in a so called ‘cars-logic’ (creating a research space), organizational aesthetics is important because of the manifest role of aesthetics in daily life of people. although within organizations attention to the human factor is increasing, there is still very little attention for employees’ aesthetic experiences in organizations. design science research aims at developing scientific valid knowledge through solving problems in practice. this dissertation initially started from wonder and personal curiosity, instead of being based on a clear field problem. but considering the amazement after finishing this dissertation, it is likely to assume that the management of organizations misses opportunities to increase employees’ work pleasure, ownership and hence their commitment and even their performance, which can be considered a field problem. in literature some ideas about organizational aesthetics are described by focusing on the stimuli in which one might perceive beauty and ugliness and why this perspective could be interesting to apply in organizations. however, these ideas did not originate from practice. it is not commonly known which aesthetic experiences people have during their daily work and because of what stimuli. in addition, there is no validated knowledge about how to make organizations more beautiful and to increase the likelihood to have positive aesthetic experiences. therefore, this dissertation contributes to the discourse on organizational aesthetics by offering insights in stimuli that cause positive and negative aesthetic experiences in practice of employees in professional organizations. professional organizations were chosen in particular because it is likely that professionals, besides their initial commitment to typical knowledge work the organization offers, probably will only feel committed to the organization based on intrinsic motivational needs, which show strong relationship with aesthetic experiences. a second argument for choosing professional organizations as the target group is the growing number of this type of organizations in the netherlands. part | introduction thus, two preliminary research questions have been defined: . which stimuli in work and professional organization trigger aesthetic experiences of employees and what are the effects for employees and organization? . what design principles can be used to develop, redesign and sustain an organizational design for professional organizations which decreases negative aesthetic experiences and increase positive aesthetic experiences of employees? before defining more specific design objectives, an extensive literature study is conducted on the fields of organizational aesthetics, aesthetics, organization and design and emotions in organizations, in particular on affective commitment. this literature study is described in the next section. . structure of this dissertation this research started from almost out of nothingness: from scarce theoretical insights about organizational aesthetics and from virtually no empirical data about this topic (e.g. akkermans et al., ; van aken et al., ; gagliardi, ) also. therefore it was decided to start writing from the beginning of the research process and not afterwards, after the phase of data collection and analysis. therefore, a kind of comprehensive anthology about organizational aesthetics has been written (part ), from which researchers can utilize thoughts for future research on organizational aesthetics. this extensive literature study describes the fields of aesthetics, organizational design and design disciplines in which the role of aesthetics is recognized (such as architecture and product design) and ends with the main insights of emotions in organizations and affective commitment. this part can be considered as an encore, a separate literature study on organizational aesthetics. for the impatient readers, in the texts numerous intermediate and final conclusions are placed. part of this dissertation begins with a summary of part , so part can be read without studying part . this second chapter concludes with the first causal diagrams on organizational aesthetics and a first draft for a research mode. chapter describes the design objectives and research strategy and its justification, and the design of the conducted empirical research is described. chapter is composed of five empirical studies which have been carried out in practice. each empirical study ends with the most important lessons for future organization design. this chapter concludes with the assessment of the developed causal diagrams based on the literature translated into design principles for organizations in which it is plausible that employees are having more positive aesthetic experiences and less negative aesthetic experiences. in chapter the results from theory and practice come together in proposed principles for beautiful organizations. design principles are translated into design interventions. an important part of this chapter consists of a description of design interventions for developing beautiful organizations. chapter describes the results of the tests of some design interventions. this thesis concludes with a reflection on the outcomes and the research process (chapter ). part | introduction part | literature study literature study since guillén ( , p. ) wrote his groundbreaking article ‘scientific management’s lost aesthetic’ and he concluded that ‘we have long neglected the aesthetic context of organizational behavior’, an increasing amount of articles about aesthetics in organizations have been published (guillén, , p. ). this literature study starts with describing the most important aspects of organizational aesthetics. like argued in the previous chapter, a small amount of literature on organizational aesthetics mainly focuses on the idea of the aesthetic perspective on organizations without extensively utilizing existing theories about aesthetics, emotions in organizations and organization design. therefore, in relation to the mentioned research questions, missing aspects in organizational aesthetics will be denoted. this resulted in specific research questions and literature research for the mentioned topics. the description of the entire literature study comprises in over pages and is shown in part of this dissertation. in this chapter only the main views of the topics are summarized. . organizational aesthetics the field of ‘organizational aesthetics’ initially was explored in the s´ by sandelands and buckner ( ), strati ( , ), ramirez ( a, b), gagliardi ( ), guillet de monthoux ( ), alvesson and berg ( ) and linstead and höpfl ( ). simultaneously this was stimulated by the growing attention of ´human´ issues in organizations like meaning, spiritually and human development at the end of the last century and the budding challenge to combine managing with designing (simon, ; boland and collopy, ). attention to aesthetics as well as the distinction of types of aesthetic properties which are used in aesthetics are largely missing in the current organization design approach (e.g. guillén, ). literature on organizational aesthetics aspires to overcome this gap and the few contributions on aesthetics in organizations mainly raise the question whether aesthetics in work and organizations could be an additional or a new perspective on organizations. the main contributions of the known literature on organizational aesthetics are the suggestions in which stimuli aesthetic value can be observed as well as the effect for the observer. an overview of these contributions is expressed in table . . main references dimension discussed main focus / key statements akkermans et al., ( ), van aken et al., ( ) akkermans et al., ( ), van aken et al., ( ) dean ( ), white ( ), gerstein, ( ); rindova et al., ( ) rindova et al. ( ), peng, wen-shien () strati ( ), alvesson & berg ( ), taylor & hansen ( ), sandelands & buckner ( ) stimuli causing aesthetic experience idem idem idem idem process beauty organizational design beauty formal properties (harmony, balance, rhythm, simplicity, repetition) in organization design organization as a whole (gestalt) the artifacts that constitute the organization’s corporate landscape part | literature study main references dimension discussed main focus / key statements strati ( ), alvesson & berg ( , witz et al, ( ), taylor & hansen ( ), warren ( ) strati ( ), alvesson & berg ( ), taylor & hansen ( ) dean et al., ( ) strati ( ), alvesson & berg ( ), taylor & hansen ( ) witz et al. ( ), akkermans et al. ( ), van aken et al. ( ) strati ( , alvesson & berg ( ), taylor & hansen ( ) akkermans et al. ( );, van aken et al. ( ) sandelands & buckner ( ), dean et al. ( ), cairns ( ) dean et al. ( ) akkermans et al.( ), van aken et al.( ) idem idem idem idem idem idem effects of org. aestth idem idem idem the physical space of the organization the idea that work compromises an essential aesthetic element s organizational decision-making aesthetic leadership: organizational management that can learn from art (artistic form) product or services beauty the images that diffuse internally and externally to the organization business performance high identification (e.g. affective commitment) job satisfaction personal well-being table . overview of organizational aesthetics literature implications for further literature study these first contributions offer a good start for selecting initial stimuli in work and organization which trigger aesthetic experiences of employees. but literature on organizational aesthetics does not or does hardly discuss the topics like the characteristics of the aesthetic process and the role of personal characteristics in this process, the parameters and principles of organization design and its relationship to the mentioned stimuli, and the possible relationship to emotions in organizations. so, actually little was known about organizational aesthetics. thus, after examining the literature on organizational aesthetics, three fields of interest were defined which needed to be studied to answer the research questions mentioned below. these fields of interest are aesthetics, organization design and emotions in organizations, particularly affective commitment. part | literature study this dissertation aspired to develop, redesign and sustain an organizational design for professional organizations which decrease negative aesthetic experiences and increases positive aesthetic experiences of professionals. for applying aesthetics in organizations, aspects of organization design were studied in literature. and more specific translated into the next research questions: . what are the most important parameters of organization design, particularly of professional organizations? . what characterizes ‘modern organizations’ and to what extent does attention to organizational aesthetics fit within these organizations? . which principles of organization design and organization development can be used to apply organizational aesthetics? for understanding aesthetic experiences of employees, literature on aesthetics was extensively studied. most important research questions on this topic were: . in which stimuli and through what qualities in these stimuli do people have aesthetic experiences? . what characterizes the aesthetic process? . what personal characteristics of the observer influence his aesthetic judgment? . what characterizes design principles of design disciplines such as architecture and product design, in which functional value and aesthetic value are inextricably combined? the literature study on aesthetics showed a strong relationship between aesthetic experiences and emotions. for example seo, barrett and bartunek ( ) emphasize the important role of antecedents and consequences of affective experience (moods and emotions) in organizations in relation to the commitment of employees. strati ( ) distinguishes the pathos (the dimensions of feeling in organizations) in organizational life. so, based on the insights of this part of the literature study, a third topic was studied in literature, which is the role of emotions in organizations, particularly the role of affect in work and affective commitment. the most important research questions for this part of the literature study were: . what is the relationship between aesthetic experiences and emotions in organizations? . how can aesthetic experiences be related to organization’s outcomes such as employee commitment, satisfaction and performance? this literature review also intended to prepare field research to focus on the research questions answered. therefore a ninth research question was added for the literature study: . which methods are suitable for examining aesthetic experiences in practice? during examining all three fields of interest, in particular methods for collecting and valuing aesthetic experiences were studied. this literature study describes the three mentioned fields of interest in a very comprehensive manner. therefore, to facilitate the readability of this dissertation the literature study is annexed in part of this dissertation. to retain any orientation in the extensive literature study, many bold printed interim summaries and conclusions are placed in the text. the main conclusions of the literature study are presented below. part | literature study part | literature study . aesthetics this dissertation is about developing beautiful organizations. philosophers like plato, plotinus, and kant, hume and hegel later in the eighteenth century, have discussed the aspect of beauty for centuries. for this study, the term ‘aesthetic’ was introduced in by the german baumgarten who derived it from the greek aisthanomai, which means perception by means of the senses. when our senses observe an object, a stimulus, a process of observation, interpretation and aesthetic judgment starts. this is called an aesthetic process experienced by the observer. in this summary of the literature review on aesthetics, in particular the antecedents of aesthetic experiences will be described as well as outcomes of the aesthetic process for the observer. antecedents of aesthetic experiences research shows that aesthetic experiences originate or are driven by several factors. broadly speaking three categories of antecedents can be identified. first, an important driver are aesthetic qualities or properties in stimuli such as objects and artifacts (e.g. mitias, ; zemach, ; goldman, ; cooper et al., ; zangwill, ; parker, ; scruton, ). these aesthetic qualities or properties can be divided into three types of properties: formal properties (harmony, balance, tension, etc.) for structuring, the representational ´properties´ (symbolic value, history, values, etc.) for identification and the expressive or sensory properties (color, sound, etc) which are used for attention (goldman, ; wagner ( ). in general it can be argued that formal properties are more objective, and representational properties are more subjective and are strongly attributed to an object by the perceiver. expressive properties can be considered as partly subjective as well as objective (‘it is red, is it?’) and are more related to the taste of the perceiver (goldman, ). a second antecedent of aesthetic experiences are personal characteristics such as sensibility, mood, education, culture, age, interests and experience. for instance, research shows that higher education correlates with a more positive aesthetic judgment. finally, environmental characteristics like ‘time to perceive’ and the presence of other stimuli such as other people or other art works affect aesthetic experiences. aesthetic process leder and colleagues (leder et al., ) provided a process view on the aesthetic experience. they indicate that the aesthetic process consists of five steps (see figure . below and also figure . in part ). the aesthetic process globally starts with observation. via interpretation and report the perceiver will come to an aesthetic judgment and (aesthetic) emotion (e.g. leder et al., ). aesthetic judgments are often expressed as a degree of beauty or ugliness. emotions often are expressed in terms of degree of arousal or activation combined with a judgment expressed in a degree of pleasantness (e.g. russell, ward and pratt, ; watson, clark and tellegen ( ). two types of aesthetic experiences can be distinguished: positive aesthetic experiences (paes: positive aesthetic judgment plus a degree of arousal) and negative aesthetic experiences (naes: negative aesthetic judgment plus degree of arousal). people assign aesthetic value to the object they perceive based on the aesthetic judgment and the caused emotion of the observer (mothershill, ; santayana, ; beardsley, ; hekkert, ). part | literature study during these aesthetic processes, some psychological mechanisms should be taken into account like aesthetic induction, prototyping and familiarity (e.g. kunst-wilson and zajonc, ; winkielman, schwarz, fazendeiro and reber, ). these psychological mechanisms affect the initial and repeated reactions during observing an object. the relationships between several mentioned variables can be expressed in the next diagram (figure . ). figure . diagram of the aesthetic process this diagram is largely based on leder’s et al. ( ) description of the aesthetic process. but their description of the process has been adapted because of the insights the literature on emotions in organizations offered. according to this literature, explained in paragraph . , an aesthetic process causes an emotion, formed by an aesthetic judgment and a degree of arousal and power. the role of aesthetics in design disciplines initially, studying aesthetics was limited to the arts. later, in design disciplines like product design and architecture the role of value is unquestionably recognized and explicitly incorporated in so- called design principles. in these design disciplines, a distinction is made between aesthetic properties (such as formal properties like harmony, repetition and unity) and non-aesthetic properties (the elements that constitute the design like bricks and window frames for a house) to realize aesthetic value as well as functional value from the user or perceiver. aesthetic properties supervene on non-aesthetic properties (e.g. zemach, ; wagner, ) which means that aesthetic properties are embedded and sometimes are hidden in those elements (non-aesthetic properties) of which an art work or object is build. for example, aesthetic properties of a painting are embedded in the paint and in the forms the artist made and for example in the relationship between them. aesthetic properties of a bicycle are embedded in the elements constituting a bicycle like a frame, the paint on the frame, or the wheels. another interesting insight arising from design disciplines is that semantics, value and meaning are accepted as aphoristic parts of a design (hekkert, ; roozenburg and eekels, ; zhang, ; krippendorff, ). they often are the beginning of a design process, and the beginning of a design causality developed by roozenburg and eekels ( ). experiencing a degree of aesthetic value can be strongly compared to the earlier mentioned experienced sum of aesthetic judgment and emotion. this design causality describes the fundamentals and methods of product design. first, they argued that a design is made by people for its properties. because of these properties it can fulfill one or more functions. by fulfilling functions a design satisfies needs, and gives people e m o ti o n aesthetic judgment arousal & power subject (personal characteristics) environment object (aesth. properties) aesthetic process . perceptual analysis . implicit memory integration . explicit classification; . cognitive mastering . evaluation part | literature study the possibility to realize one or more values. transferring these fundamentals, the design of the organization needs to change as a consequence of changing roles and needs of the employees in this case. assuming that when needs and values of employees are changing, like sense making(weick, ), meaning or experiencing aesthetics, considering that properties can fulfill one or more functions, and by fulfilling functions a design satisfies needs that give people the possibility to realize one or more values, also the properties will have to change as well. this design causality is expressed below (figure . ). figure . design fundamentals roozenburg and eekels ( ) zhang ( ) strongly advocates that the function of design is to positively support employees’ motivational needs such as emotional needs (emotion and affects).this perspective explains human’s various needs, environmental factors, and their impact on goal-oriented commitments. as a human-made thing, he argues, ‘ideally, purposely envisioned to fulfill human needs and to support human values. creation and design should then be guided them by such understanding’ (zhang, , p. ). an overview of the main contributions about aesthetics is expressed in table . . the main considerations about literature on aesthetics are: . aesthetic experiences are perceived in or attributed by aesthetic properties in objects and artifacts: the formal properties (harmony, balance, tension, etc.) for structuring, the representational ´properties´ (symbolic value, history, values, etc.)for identification and the expressive or sensory properties (color, sound, etc) for attention. . several types of aesthetic experiences can be distinguished: cognitive (intellectual), perceptual, emotional and transcendental, moral, religious and sexual experiences. . the probability of positive aesthetic judgments and positive emotion - and less negative aesthetic judgments and less negative emotion - increases in proportion as the object, artifact or event contains more aesthetic properties. . aesthetic properties supervene on non-aesthetic properties. . the antecedents of experiencing aesthetics can be divided into personal characteristics (sensibility, mood, education, culture, age, interests, experience), characteristics of the object or artifact (the degree of aesthetic properties) and environmental characteristics (time to perceive, presence of other stimuli, . the aesthetic process globally starts with observation. via interpretation and report the perceiver will come to aesthetic judgment and (aesthetic) emotion . people’s awareness of the aesthetic quality of their environment and improving this aesthetic quality, can be influenced by working on the several aspects defined within the ontology of the aesthetic quality of objects. to avoid the discussion of taste, while this is people and organization related, in any case the aesthetic quality of objects can be improved by working on the primary or formal and expressive qualities of objects and artifacts. assuming that these qualities forcefully supervene on the non-aesthetic properties of work and organizations. working on the secondary qualities of objects are probably related to organization values and identity. . it is quite reasonable that aesthetic processes within an organization will take place too; form properties needs values function part | literature study . these will be experienced under more or less the same environmental conditions like a safe environment, a specific context, scale, time (period of maturation), with less social activity (derivation) and relation with other different objects; . the aesthetic experiencing process results in an aesthetic judgment and an emotion as well. they can be positive (positive aesthetic experiences: paes) and negative (negative aesthetic experiences: naes). pleasantness, joyfulness and meaning are often mentioned emotions related to aesthetic experiences; . during aesthetic processes, some psychological mechanisms should be taken into account like aesthetic induction, prototyping, familiarity; . the design principles of many design disciplines (except organization design) can be considered as user-centered. examples are useful, affordable, understandable, unobtrusive, honest, long-lasting and environmental-friendly; . the design principles of many design disciplines (except organization design) include aesthetic aspects for realizing aesthetic value for the user (design based on values, needs, functions and properties. part | literature study main references dimension discussed main focus / key statements reber et al. ( ), van den braembussche ( ), stecker ( ), lehar ( ), dickie ( ), beardsley ( ), merleau-ponty ( ), ingarden ( ), mothershill ( ) urmson ( ), baumgarten ( ), dewey ( , ), buchanan & margolin ( ), Östman ( ), cooper et al., ), pepper ( ), leder et al. ( ), parker ( ), scruton ( ) beardsley ( ), osborne ( ), dziemidok ( ), ginsberg ( ), mitias ( ), girod et al. ( ), ingarden ( ), scruton ( ) dickie ( ), pepper ( ), beardsley ( ), osborne ( ), mitias ( ), goldman ( ), zemach ( ), wagner ( ), leyton & ramachandran ( ), carroll ( ), zangwill ( ), parker perspectives on aesthetics aesthetic experience aesthetic experience aesthetic quality and properties the objectivism view (based on plato) claims that beauty is a property of an object that produces a pleasurable experience in any perceiver. the subjectivist view on the contrary, states that beauty is ‘a function of idiosyncratic qualities of the perceiver’. the interactionist perspective suggests that a sense of beauty emerges from patterns in a way people and object relate. aesthetic experiences are perceived during a sensory, cognitive, affective, interactive and valuation process observing or even communicating with an object or event aesthetic experiences lead to a pleasurable, enjoyable and meaningful state of mind experiencing aesthetics requires an aesthetic attitude and interest of the viewer or at least attention for it. and being attended by ‘something beautiful’ the ability to apprehend and understand the several aesthetic properties of the object or event, keeping ingarden’s mentioned features of the viewer in mind like cultural background and tradition, social economical status, and education. disinterested interest means a kind of pleasure that is not connected with desire (aesthetic interest and involvement), but this interest is caused by stimuli (´being attended’) which arouses observers cognition, expressiveness (emotional), identity and imagination (holistic, empathic and synthetic). people are having aesthetic experiences because of the (degree of) recognition or attribution of aesthetic qualities or properties in the object or artifact they observe. literature distinguishes many types of aesthetic qualities. these aesthetic qualities or properties show some similarities and differences. the distinguished aesthetic qualities or properties can be ordered by gradation (objective to subjective). a tripartition of formal, representational and expressive aesthetic properties these can be made. part | literature study main references dimension discussed main focus / key statements ( ), scruton ( ) . ingarden ( ) parson ( ), horner ( ), parker ( ), leder et al. ( ), fairchild ( ) , reber et al. ( ) zajonc ( ), reber, winkielman, & schwarz ( ), mastandrea, bartoli & carrus ( ), leder et al. ( ), mcallister ( ), melchionne ( ) frijda ( ), leder et al. ( ), csikszentmihalyi ( ) warren ( ) aesthetic process aesthetic process aesthetic process methods for collecting /analyzing data leyton and ramachandran’s list of formal properties is full-featured and validated and has been used in the field research of this project. many respondents have recognized and confirmed these formal properties. having aesthetic experiences can be considered as a process, in which the phases of perceptual analysis, implicit memory integration, explicit classification, cognitive mastering and evaluation take place. the aesthetic process will lead to aesthetic judgment (a result of the evaluation of the cognitive mastering stage) and aesthetic emotion (an emotional reaction which is a by-product of the processing stages). according to the objectivist view, aesthetic judgment only must be made based on (aesthetic) properties of observed the object or artifact. following the subjectivist view, beauty is a function of idiosyncratic qualities of the perceiver. the theory of aesthetic reflexivity claims that aesthetic experiences in workplaces effect experiencing self and others, objectifying experience and associating experience. psychological mechanisms such as affect heuristic, mere exposure effect, priming, processing fluency, aesthetic induction, prototyping and familiarity and verbal overshadowing affects aesthetic judgment of people. aspects of the environment in which the aesthetic experience takes place are a safe environment, a specific context (clean, blank, spacious environment, limited information), scale, time (period of maturation), with less social activity (derivation) and relation with other different objects being frequently noted. ethno-methodological approach, interviewing employees (‘rich narrative data’) and taking pictures and discussed them (´talking pictures´ as part of the technique of photo-elicitation) table . overview of aesthetics literature part | literature study . organization design after studying literature on aesthetics, it is likely that also in organizations aesthetic properties, which cause aesthetic experiences, supervene on non-aesthetic properties. therefore literature on organization design was examined. which non-aesthetic properties, according to this literature constitutes an organization? and is organization design receptive for semantics, value and meaning, or even aesthetics like other design disciplines? parameters of organization design the most common and useful models for organizations design are waterman, peters and phillips’ - s model (known as the mckinsey’s -s model) and weisbord’s six-box model (burke and litwin, ; gavrea, ). both models have more or less the same design variables, which are relationships, structure, leadership, purposes, rewards and helpful mechanisms (six-box model; weisbord, ) and system, structure, style, strategy, staff, skills, staff ( -s model; waterman et al., ). the -s model seems to be more known and is used in holland (van tuijl & laupman, ). this model was transferred by weggeman to a more european variant, the esh model, because of the different opinions about management and organizations in european and american organizations (weggeman, ). this esh model contains the following design components: structure, culture, employees, management style, strategy and system. if these components concern all organization design parameters, it is quite likely that employees are having aesthetic experiences triggered by these components, which will be called organizational aesthetic stimuli (oas). developments in organization design considering the in literature, changes in organizations, affect and care about people in which appreciating and holistic values, meaning and design thinking have an important role , and seem to be the characteristics or even the requirements of new organizations (e.g. guillén, ; witkin, ; pascale et al., ; whitney, ; bryan and joyce, ; hatchuel, ). the notion of the role of value and meaning in organizations has been considered by several researchers (e.g. scott and davies, ; adler, ; whitney, ; bryan and joyce, ; meglino and ravlin, ). insights of the theories of sense making in organizations (weick, ) and the person- organization fit (e.g. chatman, ; o’reilly et al., ; kristof, ; finegan, ), particularly about goal and value congruence, show the important role of values related to affective commitment. so, the arguments for having attention to changing values and needs of employees and the consequences for organization functions are extensively advocated in literature. whether the attention to beauty because of beauty needs more arguments for being adopted in organizations, attention to organizational aesthetics can easily be included in the observed changes in organizations. organizations seem to be established to guarantee business economic value and to achieve continuity. adding aesthetic value to organization design means - using roozenburg and eekels’ design causality - that a second design causality can be added to a more traditional design causality for organization design. part | literature study figure . extended design fundamentals (based on roozenburg and eekels, ) the lower process represents a more contemporary view on organizations in which the role of values is not considered as important and therefore is omitted. the upper process expresses the earlier showed design causality starting with aesthetic value. the preliminary and somewhat artificial separation of both design causalities encourages the discussion about the difference between good and beauty in organizations, the functional and aesthetic value and the ethical and aesthetical judgment. therefore, finally literature on emotions in organizations has been examined. initially to understand the role of emotions in organizations and secondly to find out whether aesthetic value and business economic value conflict or reinforce each other. table . shows an overview of main focus and key statements about organization design. the main considerations about organization design are: . the few contributions on organizational aesthetics mainly raise the question whether aesthetics in work and organizations could be an additional or new perspective on organizations. . the attention for aesthetic aspects (aesthetic properties, aesthetic experiences and value) as well as the distinction of types of aesthetic properties which are used in aesthetics are largely missing in the current organization design approach; . the esh-model (based on mckinsey’s -s model) or weisbord’s six-box model seem to be the most fruitful models for designing organizations in which aesthetic aspects can be uncovered and embedded; . organizations are changing to more responsive, sensible and life affirming organizations in which creating value, sense making and meaning, narrative experiences and relations between employees become important. an aesthetic perspective on organizations fits within these developments; . principles of design thinking like abduction, through collaboration and human-centered could enrich the current perspective on organization design. form esh-components: (system, staff, strategy, management style, culture and structure) and first ideas of oas like process beauty, formal properties, artifacts, physical space and work aesthetic properties - formal - representational - expressive needs aesthetic experiences positive emotions meaning values aesthetic value function offering aesthetic experiences business economic function continuity income functional properties (e.g. effectiveness, efficiency) supervene business economic value part | literature study main references dimension discussed main focus / key statements galbraith ( ), nadler & tushman ( ), mintzberg ( ), gerstein ( ), hatchuel ( ), van aken ( ), jonker et al. ( ), scott and davies ( ), gavrea ( ) chandler ( ), minzberg ( ), boonstra ( ), gerstein ( ), romme and endenburg ( ), lekanne deprez and tissen ( ) guillén ( ), pine and gilmore ( ), hatchuel ( ), peters ( ), mcmillan ( ), (pascale et al., ), cairns ( ), bryan and joyce ( ), adler ( ), witkin ( ), taptiklis ( ), avital et al. ( ), whitney’s ( ) herzberg et al. ( ), hackman & oldham ( ), holman, clegg & waterson ( ), birnbaum & somers ( , mohrman ( ), organization design process of design modern organizations job / work design process design two main schools to distinguish: the classical school considers the organization design as a triangle of structure and reward system. the human relations approach on organizations adds information and decision process to it. whereas the people´s perspective on organization design distinguishes task, structure, information and decision processes, reward systems and people as the basic ingredients of an organization. most mentioned models for organization design parameters are: force field analysis, the leavitt’s model, weisbord's six box model, galbraith's star model, nadler and tushman's congruence model, mckinsey's -s model, the ‘four quadrants’ of bolman and deal, burke-litwin model and freedman’s swamp model. most used models in practice are the weisbord's six box model and -s model. the process of designing organizations should start with the question of what the purpose is of the organization (re)design, taking into account the needs of the organization. it could be assumed that the change of form follows function into form follows meaning affects the approach of values in organizations (as well as their function). main features of ‘new organizations’ can be regarded as a motivational perspective on design, like zhang ( ) supports. this perspective explains human’s various needs, the relationship among psychological needs, states attribution, and environmental factors and their impact on goal-oriented commitments. the purpose of (re)design then is to positively supports employees’ motivational needs like emotional needs (emotion and affects). strong attention to a "social-technical system" within an "open" system-view. growing attention to two types of factors, namely motivators (intrinsic to the work itself like achievement, recognition and responsibility) and hygiene factors (extrinsic to the work like work conditions, pay and supervision). growing attention to job dimensions like skill and task variety, task identity, task significance, autonomy, part | literature study main references dimension discussed main focus / key statements etzioni ( ), alvesson ( ), galbraith ( ), maister, ; bell ( ), drucker ( ), davenport et al. ( ), shapero ( ), morhman ( ), weggeman ( ) simon ( ), schön ( ), boland & collopy ( ), weick ( ), tzonis ( ), orlikowski ( ), dunne & martin, ), brown ( ) avital et al., ( ), zandee ( ), fairchild ( ), barrett and cooperrider ( ) hanson ( ), schön ( ), simon ( ), hanson ( ) professional organizations design thinking methods for collecting /analyzing data and job-based feedback. attention to total quality management (tqm), business process redesign (bpr) and the ‘eclectic approach’ to the radical design of business processes because of three challenge organize work effectively and efficiently performed; ) organize work so that it can be effectively managed and ; ) it offers potential for a competitive advantage. knowledge is a central feature of a post-industrial society; productivity is becoming dependent on the application and development of new knowledge, and on the contributions of specialist knowledge workers knowledge workers need different compensation structures, management and leadership styles, and complementary organizational structure and processes. characteristics of the design of professional organizations: work designs are dynamic, work is designed for collaboration, work designs focus on the larger system and local performance and work is designed for learning. for many professionals and managers design is as a daily activity managers need to understand and coordinate variability, complexity, and effectiveness. therefore they need to create design that mixes together perceptual and conceptual modes of action or moves back and forth between these modes or rely on multiple compounding of abstraction design is understood to be relational and it cannot be conceived without people and their practices. stakeholders are co-designers and designers are another kind of stakeholder. appreciative inquiry morphological / ontology mapping, process flows, socio diagrams table . overview of literature on organization design part | literature study . emotions in organizations & affective commitment emotions like pleasure and judgment after perceiving an object or artifact could be considered as a form of affective commitment (rafaeli and vilnai-yavetz, ). both, the arts as well as affective commitment, aspire to effect positive emotions like pleasure, and also well-being and meaning for the perceiver. they can cause a positive affect for the perceiver which causes a positive attitude towards the object or artifact. both the emotion and the aesthetic judgment can be related and possibly plotted in the common used models of emotions, like the watson, clark and tellegen circumflex ( ) as well as in the russell, ward and pratt two-dimension matrix ( ). both models (matrices) distinguish a degree of judgment as well as a degree of emotional impact, together resulting in an emotion. this means that aesthetic judgments can be scored between beautiful (pleasant) and ugly (unpleasant), as well on the axis of high activation and low activation. positive emotions in organizations contribute to job satisfaction and to commitment, and also to performance (e.g. judge, scott and ilies, ;lillius et al., ). negative emotions negatively influence these outcomes, because they negatively influence future negative emotions and possibly also future positive emotions. they can be considered as stronger than positive emotions, so they should be avoided (e.g. baumeister et al., ; amabile and kramer, ). in the section above, the results of an aesthetic experience, an emotion, are related to the general theory of emotions in organizations. for another reason, the concept of affective commitment is relevant for this dissertation affective commitment can be defined as ‘positive feelings of identification with, attachment to, and involvement in the work organization’ (meyer and allen, , p. ). this definition shows a strong relation with the above mentioned motivational needs as part of the mentioned design causality. and also interesting, affective commitment, often regarded alongside continuance commitment as one of the components of organization commitment, shows the strongest correlation with job performance, organizational citizenship behavior, role conflict and attendance and is the strongest and most consistent predictor of organizational outcomes like employee retention and performance. thus, by adding aesthetic value to the organization, via affective commitment, attention to organizational aesthetics indirectly contributes to performance. this causality is expressed in the scheme below. figure . causality emotions and outcomes the affective events theory (aet) of weiss and cropanzano ( ) holds all the aspects (organization design, aesthetic experiences as part of affective events and the relation to affective commitment) of the research question of this dissertation. their framework (showed in fig. . in paragraph . of part ) is extensively validated and supported with quantitative research results and was used for this dissertation. table . shows an overview of main focus and key statements about emotions in organizations and affective commitment. positive emotions negative emotions affective commitment - / - + - / - performance part | literature study main references dimension discussed main focus / key statements russell, ward & pratt ( ), watson, clark & tellegen ( ), zajonc ( , , ), watson & clark ( ), pekrun & frese ( ), weiss & cropanzano ( ), ryan & deci ( ), russell ( ), seo, barrett & bartunek ( ), fineman ( ), mignonac & herrbach ( ), ashton- james & ashkanasy ( ), fisher ( , ) chatman ( ), meyer & allen ( , , ), morrow ( ), weiss & cropanzano ( ), fredrickson ( , ), meyer et al. ( ), allen et al. ( ), ahskanasy ( ), brief & weiss, ( ), visagie ( ) affect & mood at work affective commitment state affect (mood) must be distinguished from emotions which are more intense, shorter lived and have definite cause. but mood must be considered as an antecedent of aesthetic experiences. positive emotions in organizations contribute to job satisfaction and commitment, and also to performance. employees experience nearly the full range of emotions in their workplace, as they do outside their workplace, together with emotions more specific to the work environment. negative emotions are stronger than positive emotions (‘bad events had longer lasting effects. and bad events seem to produce stronger reactions than good ones’). affective experience can be structured in two or three dimensions: a degree of pleasantness, degree of arousal and a degree of power. of these three structures, pleasantness is the most frequently found dimension of affective experience, combined with either arousal or power. in literature, three lists of emotions are dominant: first, the russell, ward and pratt ( ) two dimensions- pleasure-displeasure and degree of arousal-denote matrix, the circumflex of watson, clark and tellegen, and third, fisher’s job emotion scale (jes). affective commitment (compared to other types of commitment) is the strongest and most consistent predictor of organizational outcomes like employee retention. affective commitment has the strongest correlation with job performance, organizational citizenship behavior, role conflict and attendance. part | literature study main references dimension discussed main focus / key statements fisher ( ), watson and tellegen ( ), russell, ward and pratt ( ), fredrickson, waugh, tugade and larkin ( ), russell, weiss and mendelsohn ( ), robinson and clore ( ), grandey et al. ( ), sørensen ( ), sandelands and buckner ( ), lang ( ), morris et al. ( ), desmet ( ). methods for collecting /analyzing data the affective events theory (weiss and cropanzano, ) holds all the aspects (organization design, aesthetic experiences as part of affective events and the relation to affective commitment) of the research question of this dissertation, is validated and extensively supported with quantitative research results and was used for this dissertation. for measuring affective experiences like aesthetic experiences, a daily used self-report, possibly combined with a survey like panas-x, is a useful method for data collection. particularly in professional or knowledge-intensive organizations, professional commitment needs to be considered in addition to affective commitment. the antecedents of affective commitment can be divided into personal characteristics, structural characteristics, job-related characteristics and work experiences. questionnaires, job emotions scales, affect scales, modified differential emotions scale (mdes), affect grid, self-reports, verbal self report (vesr), visual self report (visr) table . overview of literature on emotion in organizations part | literature study the main other considerations about emotions in organizations are: . positive emotions in organizations contribute to job satisfaction and commitment, and also to performance. but also negative emotions influence these outcomes. they can be considered as stronger than positive emotions, so they should be avoided. . employees experience nearly the full range of emotions inside their workplace, as they do outside their workplace, together with emotions more specific for the work environment; . in literature, three lists of emotions are dominant: first, the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix; second, the circumflex of watson, clark and tellegen ( ); and third, fisher’s ( ) job emotion scale (jes); . the affective events theory (weiss and cropanzano, ) holds all the aspects (organization design, aesthetic experiences as part of affective events and the relation to affective commitment) of the research question of this dissertation, is validated and extensively supported with quantitative research results and was used for this dissertation; . for measuring affective experiences like aesthetic experiences, a daily used self-report, possibly combined with a survey like panas-x, is a useful method for data collection; . affective commitment (compared to other types of commitment) is the strongest and most consistent predictor of organizational outcomes like employee retention; . affective commitment shows the strongest correlation with job performance, organizational citizenship behavior, role conflict and attendance; . particularly in professional or knowledge-intensive organizations, professional commitment needs to be considered in addition to affective commitment; . basch’s and fisher’s affective events-emotions matrix could be a useful list for categorizing events in organizations; . the antecedents of affective commitment can be divided into personal characteristics, structural characteristics, job-related characteristics and work experiences. part | literature study . combining theories: an organizational aesthetics framework an existing, validated and useful theory in which the three topics aesthetics, organization and design and affective commitment coincide is one of the major findings. this affective events theory (aet) developed by weiss and cropanzano ( ) is based on the idea that employees want to remain in organizations that provide them with positive work experiences because they value these experiences and expect them to continue (meyer and allen, ). or citing ashton-james and ashkanasy ( , p. ), who adopted aet for their research like many other researchers did, ‘the crux of aet is that elements of the organizational environment that are perceived to facilitate or to impair an organizational member’s progress toward workplace goals leads to transient positive or negative affective responses.’ the theory is smoothly connected to the research model of this dissertation which was developed in the phase of the proposal of this dissertation. aet is often used and well validated by quantitative and qualitative data in many studies and published in the peer-reviewed literature (e.g. see fisher, b; o’shea, ashkanasy, gallois and härtel, , ; weiss et al., ). aet is developed for a broad range of affective events, experiences and emotions in organizations. aesthetics in organizations can be considered a specific experience with specific features and characteristics. therefore, aet is adapted in order to influence the aesthetic experiences of employees in knowledge-intensive or professional organizations through organizational design ultimately to enhance the affective commitment of these professionals. figure . the initial organizational aesthetics framework object subject (observer) properties aesthetic formal, expressive and representational properties needs motivational needs positive emotions caused by aesthetic experiences values aesthetic value function offering employees positive aesthetic experiences form organization design - organizational aesthetic stimuli (oas) - conditions for having paes/naes in work events job / work design - oas work events - oas aesthetic process aesthetic judgment - ‘beautiful work’ - ‘beautiful organization’ (paes / naes) emotions employee - gender - age - education - years of occupation - years in organization - religion - mood - aesthetic sensitivity affective commitment part | literature study this literature study on three topics, particularly the combination of findings, provides new insights into aesthetics in organizations. the adjustments to weiss‘s and cropanzano’s affective events theory, the addition of aesthetics, and the reasons for it are as follows. ‘environmental conditions are of paramount importance for the aesthetic experience’, csikszentmihalyi ( , p. ) stated. the unity of aesthetic properties of an object or artifact and a perceiver in one event is what creates the aesthetic situation (mitias, ). during work, the organization forms the environment where events and aesthetic experiences take place. organizational characteristics, especially physical but also psychological, have been proven as employee satisfying (meyer et al. ; noe et al., ; daft, ; kaptijn, ; brook et al. ; morris and steers, ). there fore a direct connection from organizational to design affective reactions is added from the assumption that characteristics of organizational design can lead to aesthetic experiences. as obvious in many design disciplines like product design, architecture or multimedia design, a distinction is made between aesthetic properties and non-aesthetic properties to realize aesthetic value and functional value from the user or perceiver. guillén ( ) conclude that we have long neglected the aesthetic context of organizational behavior. he refers to architects, who worked with the design principle of unity, order and purity (examples of formal properties), which should be directive for any design, according to guillén. thus, in the first block of the adapted aet, aesthetic properties are added to the characteristics of the organizational design. the use of formal (balance, harmony, unity etc.), representative (values, symbolic, historic) and expressive / sensory properties could be a possible distinction of aesthetic properties. these represent the most commonly found classifications of aesthetic properties. for defining the elements of the organization design, mckinsey’s -s model or weisbord’s six-box model seem to be most the used models for designing organizations in which aesthetic aspects can be uncovered and embedded. the heart of the model is formed by the events taking place in the organization. kaptijn ( ) found that ‘the effect of the mediator is large in relation to affective commitment to colleagues, where the influence from structural characteristics decreases from when the work experiences is taken into account’ (kaptijn, , p. ). the categories of affective events developed by basch and fisher ( ) initially seem very useful, complemented with typical ‘professional events’ like learning or designing. the occasional events as well as organization characteristics lead the perceiver to certain emotions. the aesthetic process will lead to aesthetic judgment (a result of the evaluation of the cognitive mastering stage) and aesthetic emotion (an emotional reaction which is a by-product of the processing stages), leder et al. ( ) claim. literature about other types of emotions (like basch and fisher, ; russell, ward and pratt, ; watson, clark and tellegen, ) combine these two results in the distinction of positive and negative emotions and pleasure and displeasure. beautiful, harmonious, elegant are often used types of aesthetic ratings or judgments a viewer might have after having positive aesthetic experience. pleasant, exiting, arousing, happiness, joy and affection are positive emotions a perceiver might have after having this experience. the difficulty with defining judgments and types of emotions is the variety of judgments and emotions as the results of an aesthetic process and the relations between the judgment and the emotion. the most common categories of emotions earlier mentioned claim that they cover all type of emotions, divided into positive and negative emotions. it is hard to make a translation of the results of aesthetic experiences to the generic emotions. basch’s and fisher’s ( ) job emotion scale (jes), the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix, or the circumflex of watson, clark and tellegen ( ) (and linked panas-x scoring) could make that translation could be useful instruments during field research for making this translation. the literature on aesthetics is more focused on aesthetic judgment (by the discussion on taste) than on the emotion that constitute the opinion. leder et al. ( ) talk about ‘a by-product’ of the processing stages of the aesthetic process. the question is whether a negative part | literature study aesthetic judgment (for example of a painting) necessarily leads to a negative emotion. the aesthetic evaluation will have little impact on the emotions of the viewer as much significance to his opinion. so possibly, the aesthetic judgment (positive versus negative) as well as the emotion (positive versus negative) after having an aesthetic experience needs to be measured. using a affect grid could be useful, like russell, weiss and mendelsohn ( ) proposed, in which the emotion as well as the aesthetic judgment of the perceiver are registered after an event. the dispositions in the aet framework concerning the characteristics of the perceiver. bowling, beehr, wagner, and libkuman ( ) propose three mechanisms: dispositions ) influence employees' equilibrium or adaptation level of job satisfaction, ) influence employees' sensitivity to workplace events, and ) influence the speed at which job satisfaction returns to equilibrium after one is exposed to a workplace event. other researchers also showed that the effects of trait affectivity on job satisfaction are mediated by state affect (ilies and judge, ; weiss ). from the literature on aesthetics, specific aspects of disposition could be added. experiencing aesthetics requires an aesthetic attitude and interest of the viewer or at least thought for it. also cultural background and tradition, social economical status, education, taste, personal experiences and interests with and exposure to these influence the affective reactions of the perceiver. in the right part of the model, the subject (observer) part, weiss and cropanzano in their aet model distinguish job satisfaction as the main outcome beside judgments driven behavior and affective driven behavior. most empirical studies on employee satisfaction, commitment, engagement, involvement, performance have focused on affective commitment because this type of commitment is the strongest and most consistent predictor of organizational outcomes like employee retention (meyer et al., ; allen et al., ; meyer smith, ; rhoades et al., ; shivangulula, ). other research shows that affective commitment is most strongly correlating with job performance, organizational citizenship behavior, role conflict and attendance, followed by normative commitment (meyer et al, ; witzel and tagger, ; shivangulula, ; visagie, ; cohen and kirchmeyer, ). matzler et al. ( ) argued that employee satisfaction is a strong predictor of affective commitment. visagie ( ) proved that affective commitment (of the three forms of commitment) shows a strongest correlation with employee attitudes towards change, perceptions of training for change, need for change and organizational benefit. vianello et al. ( ) proved strong correlation between affective commitment and elevation at work. considering the aspects meyer and allen ( ) mention in their developed survey for measuring commitment, many of these are strongly related to the affective events weiss and cropanzano described. in paragraph and table . also the relationship between affective commitment and performance has been described. many studies show strong causality between both outcomes. but in the proposed organizational aesthetics framework only the outcome of affective commitment is showed. this is done on purpose to avoid a focus on the discussion whether attention to aesthetics contributes to performance. criticism of the theory is another criterion for deciding whether or not to adopt aet in this dissertation. in the above mentioned arguments for the use and adaptation of aet the criticisms are considered and processed. ahskanasy’s ( ) concerns about weiss and cropanzano didn’t incorporate all common used categories of emotions isn’t relevant in this dissertation which is primarily concerning aesthetic experiences. lindsay’s ( ) and basch’s and fisher’s ( ) critique about the not operationalized boxes of the different factors of the model like features of the organizations or dispositions is recognized. for the more specific details of the factors of the model, the many theories and models of organization design, affective events, affective emotions and dispositions by experiencing aesthetics will be examined. for example, common models for organization design like mckinsey’s -s model or weisbord’s six-box model, the categories of affective events developed by basch and part | literature study fisher ( ), basch’s and fisher’s ( ) job emotion scale (jes), the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix, or the circumflex of watson, clark and tellegen ( ) for defining emotions and the specific mentioned dispositions for experiencing aesthetics will enrich the model. lindsay’s second critique is about the missing of other factors that might contribute to the affect and judgment driven behaviors. her critique, quite similar to little’s ( ), based on her quantitative research results, is that some of the paths between the boxes in the model are not in the right direction. she argued that previous reactions could influence behavior in future and new emotion may predict behavior better than the original felt experience, which is not part of the framework. this touches the phenomena of habituation of beauty of ugliness. examining the aesthetic experiences of employees over time, it is quite assumable that these will change, certainly with regard to positive aesthetic experiences. the aesthetic judgment and/or the emotion due to this judgment will possibly be less positive or at least be less activated. when the aesthetic judgment and/or the emotion is changing over time, the affective commitment of the employee will change as well. changing and surprising, being confronted with something less beautiful is needed for re- appreciating beauty. little’s second critique on aet is that the framework was not developed for measuring affective reactions and attitudes over time. for example fredrickson ( ) and later cohn et al. ( ) emphasize the importance of earlier experiences and their influence on future events. the result of the field research will validate these critiques. implications for field research the literature study has resulted in a new model or framework for organizational aesthetics. field research needs to be conducted to literally filling in the boxes and connection. from the upper part of the framework, the box ‘value’, particularly aesthetic value, actually is the starting point of this dissertation. initially, aesthetic value has been defined, but field research must be conducted to examine in which stimuli (organizational aesthetic stimuli: oas) employees experience aesthetic value and how much. based on literature the boxes ‘needs’ and ‘function’ can globally be described. this means that the major challenge for field research is to examine which oas trigger employees´ aesthetic experiences and because of which aesthetic properties. to answer this second question, possibly the tripartition of aesthetic properties (formal, representational and expressive properties) found in literature can be used. the design causality of roozenburg and eekels ends in the consequences of form which can be considered as the observed object, the organization. here starts weiss and cropanzano’s affective events theory. in their opinion, the characteristics of the organization, besides personal characteristics, influence the process of events to affective reactions (read: outcome of the aesthetic process). from literature is known what kind of emotions are caused by specific events. unknown is what kind of positive and negative aesthetic experiences (paes and naes) are caused by specific events directly and / or indirectly influenced by characteristics of the organization and personal characteristics. so, a second major challenge for field research is to examine which events are causing aesthetic experiences and which characteristics of the organization and the observer are influencing this process. in section methodology, the design objectives are identified based on the new developed on the organizational aesthetics framework. part | literature study besides acquiring knowledge about these various topics and having answered the research questions for the literature review, this review was conducted to gather field research methods. based on this literature review the following methods and models seem to be appropriate to use in the field research. methods for collecting data: a variety of methods for eliciting an organizational member’s aesthetic experience such as direct questioning, indirect questioning, asking for commentary on relived events and drawing feelings (jones, ); a self-report for collecting positive and negative aesthetic experiences (sandelands, grandey et al.); a survey for collecting data about affective commitment (weiss and copranzano); an affect grid (russell, weiss and mendelsohn, ) for positioning the aesthetic judgments and emotions related to the collected aesthetic experiences. methods for analyzing data: the method of coding for indicating the type of events, type of properties and relations with components of the organization design which are mentioned in the collected aesthetic experiences for comparing these aspects with all the collected experiences; the list of categories of events (fisher) for indicating the events in which respondents experienced aesthetics; the distinction of the type of properties (formal, representational and expressive / sensory properties) for indicating the type of property in which respondents experience aesthetics. methods / models for representing data: the esh-model for linking the role of the components of organization design to the organizational aesthetic stimuli (oas) in which respondents experienced aesthetics; cimo-configurations for constructing design interventions (van aken et al.; trandfield, guba and lincoln). finally, combining theories also implies combining different languages of the three topics aesthetics, organization and design and affective commitment to the ‘new’ language of organizational aesthetics. new terms and abbreviations like positive aesthetic experiences (paes) and organizational aesthetic stimuli (oas) are listed in a vocabulary for organizational aesthetics (appendix ). part | literature study part | design science research design science research the previous chapters describe why the specific phenomenon of organizational aesthetics is relevant to be examined and which concepts and methods in literature can be used to describe, conceptualize and exploit organizational aesthetics. this chapter discloses the design objectives of this dissertation, the rationale and the sources of data. finally, the used methods for data collection and analysis are proposed, which are described more in detail in chapter as part of the several empirical studies. . design objectives from the previous chapters it has become clear that aesthetics is an important phenomenon in organizations that needs to be examined in more depth. the literature has hardly touched upon the topic and therefore lacks a clear conceptual understanding of the phenomenon. in addition, in practice managers largely neglect the phenomenon whereas it seems to be of utmost importance when designing effective and efficient organizations. as the purpose of this study is to provide both academics and researchers a conceptual foundation for further action (e.g., future research and normative rules or design principles) there are two aims for this dissertation: . describe and conceptualize aesthetic experiences from an organizational perspective and examine antecedents (e.g., stimuli and properties) and consequences (e.g., employees’ affective commitment). . develop design principles (design protocol) to develop, redesign and sustain an organizational design for professional organizations that decreases negative aesthetic experiences and increases positive aesthetic experiences of employees. based on the above mentioned goals, the following research questions were developed: a. what defines organizational aesthetic experiences? b. what stimuli (organizational aesthetic stimuli: oas) and properties drive employees’ positive aesthetic experiences and negative aesthetic experiences? c. to what extent do personal characteristics influence the appreciation of oas? d. to what extent is this appreciation sustainable? e. how to exploit organizational aesthetics and f. what design principles (design protocol) can be used to reform, (re)design, create or enhance, and sustain professional organizations’ aesthetic value? first four research questions elaborate the first purpose (descriptive) of this dissertation, while research questions e and f are more normative in nature and directly focus on the organization design of beautiful organizations. given the focus of this dissertation on employees´ aesthetic experiences, related concepts like aesthetic attitude, aesthetic sensitivity, and mood will not be examined. these dispositions concern the field of psychological research, which is not the focus in this dissertation. but more importantly, related research on appreciation of the arts shows that in particular personal characteristics such as age and educational level affect appreciation of aesthetic value. and with hindsight, the results will show that not including these related concepts does not alter the findings. part | design science research . rationale: research strategy & research design this research can be characterized as design science research (dsr), i.e. inductive and prescriptive research. in this dissertation, three types of data will be used to eventually develop design principles: (i) theories from aesthetics or related disciplines, (ii) findings from empirical design research, combining empirical research with philosophical reasoning, and (iii) translating research findings from an empirical and specific area to the shared area of organizational aesthetics. important feature of this research is its exploratory and iterative nature. like mentioned earlier, there hasn’t been done much prescriptive or empirical research on this topic. therefore after each of five field studies as part of this dissertation, a reflection on the results and the contributions to design objectives followed, as well as a decision on how to continue the research. and so, inductively deriving insights from empirical data i.e. engaging with philosophical reasoning, the design principles for beautiful organizations evolved (urquhart, ). design science research the development and adoption of dsr as a new research paradigm can be considered a recent response to the increasing need for knowledge production with high practical relevance. the more traditional ‘mode knowledge production’ is predominantly driven by academic concerns (gibbons et al. ). in contrast, ‘mode knowledge production’ introduced by gibbons and his colleagues, is trans-disciplinary in nature with intensive interaction between knowledge production and knowledge dissemination and application (van aken, ). recently, researchers like tranfield and starkey ( ) and starkey and madan ( ) call for more emphasis on both mode and mode knowledge production as the former often lacks scientific relevance (i.e., relevance problem, van aken and romme, ), while the latter often cannot be generalized to other settings (i.e,, fragmentation problem, ibid). they advocate a perspective which is described as the research perspective of critical realism. critical realism - also identified by critical theory - is a philosophy of science that reflects on the foundations of social science research (e.g. gijselinckx, ). the critical realism wants to restore the balance between reflections on the objective (the only truth and scientific) and subjective (narratives). and thus critical realism can be placed between the (realistic) positivist and social constructivist thinking (knowledge production between people during interaction). critical realism tries to revisit concepts and theory, empiricism, explanation, causality, and reality. causality in critical realism does not imply - as positivism - necessary regularity, but only one mechanism that effectuates (outcomes) in a given context (gijselinckx, ). dsr holds the promise to close the relevance-rigor gap in studies on organization and management phenomena given two recent developments (van aken and romme ). first, researchers show an increasing interest in design and design science research itself (e.g., romme, ; van aken, ; huff et al., ; bate, ). the main reason is that design sciences in practice - in contrast to explanatory sciences which are interested in theoria - ‘are interested to solve improvement problems by acting upon existing entities, as well as in techne to solve construction problems to realize new entities (such as in engineering)’ (van aken, , p. ). second, more studies in the organization and management domain are adopting an evidence- based management (ebm) perspective (e.g., tranfield et al., ). this implies that value is attached to a sort of knowledge base of generalizable and transferable knowledge that can be used as solution concept for solving similar problems in similar contexts (stam , ). by combining these two trends researchers hold the key to ‘reinvent the future of organization and management studies: the relevance problem of organization and management studies can be mitigated by using the actor perspective and solution orientation of the design science research approach, and the fragmentation problem can be addressed by design-oriented research synthesis, part | design science research drawing together various research streams in order to develop design interventions to be used in ebm.’ (van aken and romme, , p. ). as such, dsr can be considered a more applied science where the aim is to improve the knowledge pool (in breath and depth) of phenomena by actively applying and testing knowledge in different settings instead of merely observing it. the paradigm of the design sciences was inspired by simon ( ), in which he explores the fundamental differences between (natural) science and the ‘sciences of the artificial’. based on this idea, van aken ( ), and later (denyer et al., ), refer to ‘the distinction between explanatory sciences (simon’s natural sciences but also including disciplines such as sociology and economics) and design sciences (most of simon’s sciences of the artificial)’ (denyer et al., ). a design science is characterized by (denyer et al., ): research questions being driven by an interest in field problems; an emphasis on the production of prescriptive knowledge, linking it to interventions and systems to produce outcomes, providing the key to solving field problems; a justification of research products largely based on pragmatic validity (do the actions based on this knowledge produce the intended outcomes?).. thus, dsr aims at developing scientific valid knowledge through solving problems in practice. as a consequence, a dsr project is characterized by a combination of two parallel streams of knowledge production (stam, ). these streams have been labeled knowledge stream and practice stream (stam, ; van aken and andriessen, ). knowledge (theory) and practice enhance each other, dsr pursues. both streams are interdependent and thus, in order to overcome a separation, knowledge and practice should be combined. andriessen ( ) introduced two distinctive but interwoven streams of inquiry, named the knowledge stream and the practice stream. whereas the practice stream aims to solve specific problems in specific situations, the knowledge stream focuses on producing generalizable and transferable knowledge that can be used as a solution concept for solving similar problems in similar contexts (stam , ). to connect to the particular modes of knowledge production in the different contexts, both streams are based on different learning cycles. whereas the practice stream is based on the problem-solving cycle or regulative cycle (van strien, ), the knowledge stream is based on the reflective cycle (van aken, ). the problem solving cycle or regulative cycle (van strien, ) consists of four phases: ) defining the problem, ) planning the intervention, ) applying the intervention, and ) evaluating the intervention. the reflective cycle is a combination of the regulative-cycle of the professional aiming at solving a unique and specific problem and the scientist aiming at the development of general knowledge which can be used in a class of comparable problems (stam, ). acknowledgement of these two different streams of knowledge production and its distinctive characteristics was an important starting point for this research. . sources of data after finishing the literature study, it became clear that there is hardly any empirical data about aesthetic experiences of people in work setting and organizations. therefore, initially managers of different dutch organizations were interviewed (for two hours a manager were asked four open-ended questions) for obtaining a first feeling by what they associate with beauty in relation to their organizations. three of these organizations responded to a call in the course of this research, supported by cnv and inaxis (ministery of home affairs), to compete for a place on the list of beautiful organizations in the netherlands. the other seven organizations were mentioned by others as ‘beautiful organizations’ or ’where beautiful things happen’. during this first study, only managers where asked for stimuli that cause aesthetic experiences. part | design science research to exclude the fact that managers speak for their employees, during a second study, not only managers but all types of employees of organizations filled out a questionnaire. all these organizations responded to a call in the course of this research, supported by cnv and inaxis (ministery of home affairs), to compete for a place on the list of beautiful organizations in the netherlands. the respondents were asked to appreciate the oas on a -points likert-scale (beauty / ugly: strong agree – strong disagree). in this survey (offered via internet after sending a personal e-mail with the login code) respondents (purposive sampling: balanced mix of personal characteristics like age, sex, education, role in the organization and years of service of random chosen respondents) were also asked (by an open-ended question) what they perceive as beautiful and ugly in their organization to control the results of ten interviews conducted in the first study. this second study produced very important and new data about what organizational aesthetic stimuli (oas) trigger aesthetic experiences and how these oas are appreciated by employees. because some of the respondents during this second study asked whether their associations with beauty concerned the organizations or the work they perform, a third study was conducted among employees of organizations to collect events in which they experience beauty and ugliness. during this third study, a first version and variant of a self-report (the beauty experience log book; bel-book) was tested, in which respondents daily registered their beautiful and ugly aesthetic experiences. because the second study showed that aesthetic appreciation by employees for oas decreases over time, during the fourth study employees who had returned to a former employer were interviewed ( by telephone, using an interview protocol with open questions). these respondents realized that, after leaving this employer and experiencing another work context, their former employer offered them more aesthetic experiences than they recognized at the moment they left this employer. during the third empirical study, aesthetic experiences of random chosen employees were collected by using the bel-book. the dissertation aspired to develop design principles that assist professional organizations to increase employees´ aesthetic experiences and decrease their aesthetic experiences that improves employees’ organizational engagement (e.g., affective commitment). the choice was for professional organizations in particular because it is likely that professionals, besides their initial commitment to typical knowledge work the organization offers, professionals probably will only feel committed to the organization based on intrinsic motivational needs, which show strong relationship with aesthetic experiences. a second argument for choosing professional organizations as the target group is the growing number of this type of organizations in the netherlands. although all first four studies were conducted in professional organizations, aesthetic experiences of professionals in particular are not the focus of this dissertation. a fifth study was conducted to collect aesthetic experiences of surgeons of hospitals and of teachers of elementary schools in holland. the bel-book was completed with an affect grid. in this affect grid (based on russell, weiss and mendelsohn ( )) respondents ranked their aesthetic experience on a scale of beauty to ugliness (x-ax) and on a scale of high versus low emotional impact (y-ax). the surgeons and teachers registered daily aesthetic experiences for two weeks. part | design science research in total, respondents of organizations participated in this research. table . shows an overview of all sources of data used for this dissertation. empirical studies methodology total number of respondents / organizations research questions study : exploratory study on phenomena of beauty and ugliness in organizations interviews managers . which organizational aesthetic stimuli (oas) do managers perceive? . why do they have attention for organizational aesthetics? . what are the revenues of attention to organizational aesthetics? study : aesthetic appreciation and role of personal characteristics survey (managers and employees) a. which organizational aesthetic stimuli (oas) do employees perceive? b. how do they appreciate organizational aesthetic stimuli (oas)? c. do personal characteristics influence their aesthetic appreciation? d. which organizational aesthetic stimuli (oas) contribute to ‘aesthetic value’ and ‘affective commitment’? study : aesthetic experiences in events self-reports (bel-book) employees a. which daily aesthetic experiences (paes) do employees have? b. how durable are their aesthetic experiences? c. what are the conditions for positive aesthetic experiences? d. is the bel-book a valid method for collecting aesthetic experiences? study : the role of position and time in aesthetic judgment interviews returned employees a. role of organizational aesthetics in returning to a former employer study : aesthetic experiences of professionals self-reports (bel-book)| survey professionals a. which daily aesthetic experiences (paes and naes) do professionals have? b. how do they value their aesthetic experiences (aesthetic judgment and emotional impact)? c. how durable are their aesthetic experiences? d. what are the conditions for positive aesthetic experiences of professionals? totals * * *= some same respondents / organizations table . overview of conducted empirical studies part | design science research . data collection and analysis to collect data on the mechanisms, contexts and outcomes, particularly about aesthetic experiences in work and organization context, no specific research methodology is available (gijselinckx, ). gijselinckx advocates a methodological eclecticism in which both quantitative and qualitative research methods are used to achieve the necessary triangulation. the essential question is: how many different methods are needed? an indication of the number of methods may be the moment when the researcher thinks 'now i find nothing new ...' and all research questions can be answered. two questions that precede are firs: what data is collected? second: what kind of sources, these data will provide? data can be collected in many ways. nogeste ( ) argues that a researcher needs to ensure credibility by defining how data is collected, the consistency in collection methods and the reliability of sources. design science research uses 'eclectic theory': any theory that argues something valuable about the problem can be used (van aken, ). with the used research methods it should be possible to explain how and why certain mechanisms (do not) work, in which context and how individuals contribute. in this dissertation, the literature studies, interviews, questionnaires and self-reports were used to collect data in practice. the described current practice of dsr usually consists of one or more (case)studies, in which the generic solution is tested. this means that the current practice will navigate the practice stream several times (van aken and andriessen, ). this is preferably done in a sequential order, the serial study, for possible interventions to best fit. van aken ( ) therefore speaks of an "evolving series of case studies”. the cycle of testing and adjusting will be applied as often as needed, until the generic solution is completed (theoretical saturation) and sufficient evidence is gathered for its activities. this process can be preceded by an “inventory series of case study(s)” to identify problems and to look for good examples of solutions (interventions) (van aken, ). before this dissertation, not many empirical data about organizational aesthetics existed. therefore, it was hard to obtain knowledge from previous research. similarly, there were hardly any research methods known for obtaining aesthetic experiences and appreciation in organizations. therefore, an ‘inventory series of case study(s)’was conducted to identify problems and to look for good examples of solutions (interventions) (van aken, ). this explorative study consists of five empirical studies, within random organizations (divergence), and has been continued in specific professional organizations (specialization and convergence) (see table . ). through this method on an iterative manner, design interventions for 'beautiful' organizations have been constructed during research and design phases. mixed methods like discussed in the previous paragraph, the empirical research of this dissertation was conducted in several phases. step by step, by using mixed methods for data collection, empirical data about the blocks of the initial organizational aesthetics framework have been acquired. through this method, inductively deriving insights from empirical data and used methods engaging with other theories (about aesthetics, organizational design and employee commitment), design principles for aesthetics in organizations evolved (urquhart, ). this also resembles a ‘template approach’ or theory elaboration approach (lee et al. ). according to lee and his colleagues, theory elaboration results in extensions to theory in cases where preexisting conceptual ideas or a part | design science research preliminary model (e.g. the process of having aesthetic experiences during events and in organization s), drives the study’s design. the consequence of inductively deriving insights from empirical data is that after finishing each empirical study a new assessment is made whether acquired data is sufficient enough to answer research questions (i.e., saturation).these are discussed in the description of the individual empirical studies in chapter as well as the reliability and validity of the used methods. an important aim of the conducted literature study was to gather empirical research methods i.e. for collecting and judging aesthetic experiences. literature on the several topics of interest, such as aesthetics and emotions in organizations, offered valuable methods like direct questioning, self- reports, an affect grid, methods of coding the type of events and type of aesthetic properties, and surveys for collecting data about affective commitment. the following research methods were used. interviews were used in the first and fourth study for collecting organizational aesthetic stimuli (oas) that trigger aesthetic experiences and for questioning returned employees about their consciousness of their aesthetic awareness. for the second and fifth study a survey was developed to examine how employees appreciate oas and whether personal characteristics affect their aesthetic appreciation. as third method for collecting data, self-reports were used, in particular the bel-books combined with an affect-grid to position the aesthetic judgment and the impact of emotion of each aesthetic experience, to collect daily positive and negative aesthetics events of employees. for analyzing quantitative data, correlation analyses, cluster analyses and canonical correlation analyses were conducted. for analyzing qualitative data, open and selective coding was used. derbaix and pahm ( ) suggested to code at least three type of affective reactions: ) affect words i.e. substantives of affective reactions (like happiness, sadness, shame, regret), ) expressions in which ‘mood’, ‘feel’ of ‘emotion’ were paired with a positive, neutral, or negative evaluation and ) statements ‘in which sometimes colorful descriptions from which it was easy to infer an affective reaction’. lilius et al. ( ) used coding in their research on compassion of work. they distinguished three categories: giving material support, giving emotional support and giving time and flexibility. basch and fisher’s (basch and fisher, ) often used ‘categories of events’ were applied for indicating the types of events and types of aesthetic experiences. finally, cimo-configurations were used to arrange and express gathered data. table . shows an overview of used methods for data collection for this dissertation. part | design science research part | empirical studies empirical studies . five empirical studies this section describes five empirical studies which were announced in table . . figure . positions the contributions of the various studies in relation to the earlier proposed organizational aesthetic framework. this framework was initially developed based on the insights of the literature study. empirical data was collected to test the specific research questions. in this study, values, needs, and function, are not empirically examined because prior research well covered this part of the theoretical framework. instead, this dissertation aimed to address the gaps identified. after each study the findings were evaluated to see to what extent prior expectations were confirmed and new questions arose. subsequent studies aimed to address these new questions too, next to the ones defined a priori. as this research primarily aims to understand the phenomena of aesthetics in an organizational context and to develop design principles, an exploratory approach would be appropriate: it enters “the field” to examine what is occurring (the lower part of the organizational aesthetic framework), rather than clearly defining and delimiting the relevant variables ahead of time. as such, this research was guided by unfolding events and discoveries. a first empirical study was examined to explore organizational aesthetics, while a second empirical study more focused on validating and further exploring the phenomenon. the third, fourth, and fifth empirical studies were in particular conducted to understand organizational aesthetics. after the description of all five studies, the methodological justification is explained and design implications are defined (the upper part of the organizational aesthetics framework). part | empirical studies figure . relationship initial organizational aesthetics framework and empirical studies data collection: - empirical study - empirical study - empirical study object subject (observer) properties aesthetic formal, expressive and representational properties needs motivational needs positive emotions caused by aesthetic experiences values aesthetic value function offering employees positive aesthetic experiences form organization design - organizational aesthetic stimuli (oas) - conditions for having paes/naes in work events job / work design - oas work events - oas aesthetic process aesthetic judgment - ‘beautiful work’ - ‘beautiful organization’ (paes / naes) emotions affective commitment data collection: - empirical study data collection: - empirical study - empirical study object subject (observer) properties aesthetic formal, expressive and representational properties needs motivational needs positive emotions caused by aesthetic experiences values aesthetic value function offering employees positive aesthetic experiences form organization design - organizational aesthetic stimuli (oas) - conditions for having paes/naes in work events job / work design - oas work events - oas aesthetic process aesthetic judgment - ‘beautiful work’ - ‘beautiful organization’ (paes / naes) emotions employee - gender - age - education - years of occupation - years in organization - religion affective commitment data collection: - empirical study - empirical study - empirical study data collection: - empirical study - empirical study part | empirical studies . . study : exploratory study on phenomena of beauty and ugliness in organizations research objectives the research objectives of the first empirical study were (i) to have a first insight of what people consider as beautiful and ugly in their organization and which stimuli (organizational aesthetic stimuli: oas) triggers aesthetic experiences, (ii) to what extent the organization uses aesthetics as a strategic starting point, (iii) how these aesthetic principles are implemented, and (iv) what the outcomes are of attention to aesthetics within an organization. methodology research context in order to obtain first insight of what people consider as beautiful and ugly in their organization, ten managers from ten randomly selected organizations were interviewed. this resulted in a unique list of oas. the selected organizations were ormit, rabobank woudenberg en omstreken, zonmw, koninklijke hulshof’s verenigde leerfabrieken bv, roc tilburg, harreveld, flevoziekenhuis, oogziekenhuis rotterdam, randstad (headquarters) and finext. the first three mentioned organizations responded to a call in the course of this investigation, supported by cnv and inaxis (ministery of home affairs), to compete for a place on the list of beautiful organizations in the netherlands. the other organizations were selected because they were listed or described as beautiful organizations by people or they responded to an appeal via social media. the degree of saturation of obtained data determined the number of managers which were interviewed. after interviewing managers, collected oas covered all dimensions cited in literature on organizational aesthetics such as products and services, image or the physical space (see table . ) and no new categories were discovered. we chose for a random design as the phenomena of aesthetics is believed to be a general phenomenon that is present in every business setting. in addition, by selecting a diverse set of companies we were able to look for common factors that influence perceptions of aesthetic value and its outcomes (mill, ). data source managers were interviewed during a conversation of approximately one and a half hour to discover manager’s first associations with organizational aesthetics. the answers of the ten managers were registered by taking notes. these notes were converted into stories about beauty in organizations, which were approved by the respondent. in order to ensure the validity and reliability of this first empirical study, we worked with a standard questionnaire and the individual stories were approved by the respondents (member check). measures during an semi-structured interview each manager was asked four open-ended questions: . which oas in your organization do you experience ugliness and beauty? . to what extent does the organization use aesthetics as a strategic starting point? . how are these aesthetic principles implemented? . what are the revenues of attention to aesthetics in the organization? analytical approach the obtained interview data was manually coded (template coding based on categories found in literature). this was preceded by a cross-case analysis. given the limited number of interviewees and the exploratory nature of the study we took a conservative approach by considering codes that were mentioned by at least out of managers ( %). it ensures a broad perspective on the phenomenon that needs to be studied more in-depth in follow-up studies. secondly, after coding, part | empirical studies the obtained data was categorized according to the five parameters of the esh model (system, employees, management style, structure, culture, strategy). this model, based on the mckinsey’s -s model but transferred to a more european variant, contains the following parameters for organization design: structure, culture, employees, management style, strategy and system (weggeman, ). the esh model was used for two reasons: ) to reduce the number of concepts and thus to better understand the construct and ) to validate that all organizations design parameters are covered. results from the analysis it became clear that a total of oas are mentioned by the managers (see appendix ). the most named oas are interior / exterior of the building (mentioned by %), people orientated management (mentioned by %), influence of staff (mentioned by %), and personal development of employees (mentioned by %). in addition, three managers mentioned the organization as a meeting place (i.e., social aspect), the visual communication (e.g. house style and printed material), and their contribution to society as important oas’s. a cross-case analysis revealed that of ( %) oas was mentioned by two or more managers and of ( %) oas was mentioned by three or more managers. this indicates the pluralistic nature of the phenomenon of aesthetics in organizations. these oas like cooperation and development opportunities are categorized according to the six organization design variables (strategy, system, structure, culture, staff, management) of the esh-model, based on the mckinsey's -s model for organization design developed by waterman and colleagues (waterman et al., ). categorizing the oas cited by the managers according to the parameters or clusters of the esh-model we can see that the items are fairly evenly divided among the parameters, which show first indications that aesthetic experiences are triggered by a wide range of oas. people assign aesthetic value to the object they perceive based on the aesthetic judgment and the caused emotion of the observer (mothershill, ; santayana, ; beardsley, ; hekkert, ). thus, following this definition, aesthetic value in organizations is not particularly experienced in only aspects representing for example structure of culture. all managers together mentioned perceived revenues of attention to beauty. the most frequently cited revenues are good image of the organization (mentioned by %), high customer satisfaction (mentioned by %), high employee commitment (mentioned by %), proud employees (mentioned by %), and positive feedback about the organization from the environment (mentioned by %). lessons learned these interviews were the first acquaintance with employees (managers) and their perceptions of beauty and ugliness within organizations. first goal of these interviews was to collect examples of aspects in which managers perceive beauty (from the employees’ perspective) in their organization, so called organizational aesthetic stimuli (oas) as part of the form box of the proposed organizational aesthetics framework. when the mentioned aspects are categorized according to the aspects of the esh-model, we can see that the items are fairly evenly divided among the esh components. beauty seems to be experienced in many organization aspects, like suggested in the literature on organizational aesthetics. furthermore, an advantage of the current empirical study may be that the data is based on manager perceptions regarding beauty and ugliness in their organization and may differ from employee perceptions. given the differences in perceptions between managers and subordinates regarding organizational aspects (e.g. ingarden, ; leyton, ; hekkert, ), more research is needed that considers organizational aesthetics from the employee perspective. part | empirical studies . . study : aesthetic appreciation and role of personal characteristics research objectives the results of the interviews in the first study give a first insight into the aspects in which employees experience beauty and ugliness in their organization. yet, this first study has been conducted within a limited set of companies using managers as key informants. to have a better understanding of aesthetic experiences in organizations a more varied type of respondents were involved. it applies not only a repetition of the first study among a larger and other target group, but also the examination of employees ‘aesthetic judgment of the list of acquired oas and the influence of their characteristics like time of employment, age, and education on this judgment. and the influence of characteristics of respondents. the main research objectives of this second study were: . examining employees ‘aesthetic judgment of oas (beautiful – ugly); . examining the influence of characteristics of respondents (e.g., tenure, age, and education) on their aesthetic appreciation; . examining the relationship between the appreciation of oas and affective commitment (e.g. pride, work pleasure, and flow experiences); . testing the completeness of the list of oas acquired during the first empirical study; methodology research context we collected data of respondents representing organizations: ormit, rabobank woudenberg en omstreken, umcg, zonmw, and dental practice dennis verhoeve. these organizations responded to a call in the course of this investigation, supported by cnv and inaxis (ministery of home affairs), to compete for a place on the list of beautiful organizations in the netherlands. ormit, rabobank woudenberg en omstreken, and zonmw also participated in the first empirical study. data source respondents representing organizations were in particular asked to appreciate oas and to register oas ( oas) which trigger aesthetic experiences. in this survey (offered via internet after sending a personal e-mail with the login code) respondents were also asked (by an open-ended question) what they perceive as beautiful and ugly in their organization to allow for comparisons with the results of the ten interviews conducted in the first study. appendix shows an overview of characteristics of respondents. respondents were selected via purposive sampling in order to obtain a balanced mix of personal characteristics like age, sex, education, role in the organization and years of service of random chosen respondents. measures a survey for examining employees’ aesthetic judgment of oas was developed based on two sources. first, the first empirical study resulted in a list of oas which were mentioned by at least out of managers ( %). this list of oas was supplemented with oas distinguished in literature on organizational aesthetics. this literature search resulted in the following overview of type of oas: process beauty (akkermans et al., ; van aken et al., ) organizational design beauty (akkermans et al., ; van aken et al., ) part | empirical studies formal properties (harmony, balance, rhythm, simplicity, repetition) in organization design (dean, ; white, ; gerstein, ; rindova et al., ). organization as a whole (gestalt) (rindova et al., ; peng, wen-shien, ) the artifacts that constitute the organization’s corporate landscape (strati, ; alvesson and berg, ; taylor and hansen, ; sandelands and buckner, ) the physical space of the organization (strati, ; alvesson and berg, ; taylor and hansen, ; witz et al, ; wasserman et al., ; wasserman and frenkel, ) the idea that work compromises an essential aesthetic element (strati, ; alvesson and berg, ; taylor and hansen, ) organizational decision-making (dean et al., ) aesthetic leadership: organizational management that can learn from art (artistic form) (strati, ; alvesson and berg, ; taylor and hansen, ) product or services beauty (witz et al, ; akkermans et al., ; van aken et al., ) the images that diffuse internally and externally to the organization (strati, ; alvesson and berg, ; taylor and hansen, ) for categorizing these oas in a simpler and process oriented way, the categories of system aesthetics, process aesthetics and result aesthetics were used. system aesthetics covers the design parameters represented by the earlier mentioned esh model. process aesthetics concerns aesthetic experiences during human action like process beauty (akkermans et al., ; van aken et al., ). result aesthetics concerns the aesthetic experiences triggered by a result and outcome such as product or services (witz et al, ; akkermans et al., ; van aken et al., ) and organization’s image (strati, ; alvesson and berg, ; taylor and hansen, ). the survey was divided into two parts: first, the respondents were asked to appreciate the oas like cooperation, qualities of colleagues, and interior on a -points likert-scale (beauty / ugly: strong agree – strong disagree). second, respondents were asked to answer open questions, including the questions ‘what do you experience as beautiful and ugly in your work and organization?’ also the fourth question of the interview in the first empirical study (the revenues of organizational aesthetics) was posed in the questionnaire. in an open-ended question respondents were asked to reflect on the acquired data of the interviews as well on a statement (pride, job satisfaction, flow, and a grade for organizational aesthetics in their organization) that the respondent scored on the level of application ( points likert-scale). in order to ensure the validity and reliability of this empirical study, we developed a survey in which the selected oas are categorized according the parameters of the esh model (structure, culture, employees, management style, strategy and system (van burg, ). this arrangement creates of form of consistency. this is corroborated by high cronbach’s alpha coefficients (> . ). to ensure external validity the survey was completed by respondents of different organizations in order to examine whether results could be generalized (van aken, ; van burg, ). second, the perceived effects of attention to organizational aesthetics (see the first empirical study) are quantitatively measured during this second study. third, by using similar labeling (codes) of qualitative data about aesthetic experiences such as were used in the first empirical study, it provides insight into the patterns that are present in the data. part | empirical studies analytical approach to answer the research questions of this empirical study four different analyses were conducted: a correlation analysis was done to examine the first relationship between oas and outcomes such as proud employees and work pleasure, two canonical analyses were performed to examine the relationship between aesthetic experiences and affective commitment and aesthetic value, and a cluster analysis (with anova) examined the relationship with demographics and the aesthetic judgment of oas. finally a qualitative analysis (i.e., selective coding) was done to test the completeness of the list of oas acquired during the first empirical study. two canonical correlation analyses (cca) were conducted to examine the relationship between two variable sets (set : oas and set : dependent variables pride, work pleasure and flow experience representing affective commitment) and the relationship between the first set and aesthetic value (set : beautiful work, beautiful organization and attention to aesthetics contributes to performance). cca is an exploratory tool to determine whether two sets of variables are independent of one another or, conversely, determining the magnitude of the relationships that may exist between the two sets (hair, et al., ). this modeling type approach was also used to explain the nature of whatever relationships exist between the sets of dependent and independent variables, generally by measuring the relative contribution of each variable to the canonical functions (relationships) that are extracted. an important advantage of cca is ‘that they may best honor the reality of psychological research’ (sherry and hanson, , p. ). sherry and hanson argue that most human behavior research examines variables that possibly have multiple effects and multiple causes. determining data results, such as classical univariate (e.g., analysis of variance [anova], regression) and multivariate (e.g., multivariate anova [manova], descriptive discriminant analysis) statistical methods that separately investigate singular causes and effects may distort the complex reality of human behavior and cognition (sherry and hanson, , p. ). most critical limitations of cca are that the method is not recommended for small samples, and cca can only detect linear correlation between two domains that is globally valid throughout both data sets (hair, et al., ). the samples concern data of respondents which is sufficient enough for measuring, which is confirmed by the significance tests. for controlling the correlation between individual variables a classical correlation analysis was conducted to examine the first relationship between oas and outcomes such as proud employees and work pleasure. the role of personal characteristics on aesthetic judgment of oas was examined by conducting a cluster analysis. a cluster analysis is an exploratory tool and data reduction tool that creates subgroups, taxonomies or clusters that are more manageable than individual data and it examines the full completeness of inter-relationships between variables (hair, et al., ). by conducting a hierarchical cluster analysis the ‘distances’ of aesthetic judgments of all respondents were examined. after profiling the found clusters can be determined. the qualitative data was manually coded (selective coding, based on the defined categories of oas after the first empirical study). this was preceded by a cross-case analysis. given the large number of respondents we took a progressive approach by considering codes that were mentioned by at least % of respondents. secondly, after coding the obtained data was categorized according to the five parameters of the esh model (system, employees, management style, structure, culture, strategy). results an overview of data is expressed in table . . all data is represented in appendix and appendix . part | empirical studies organizational aesthetic stimuli (oas) aesthetic appreciation of oas (n= ) g ra d e f o r ‘b e a u ti fu l o rg a n iz a ti o n ’ i h a v e b e a u ti fu l w o rk i a m r e g u la rl y ‘ in f lo w ’; th e s e n se o f a g re a t d a y w h e n e v e ry th in g g o e s w e ll in m y w o rk i a m n o t p ro u d o n m y o rg a n iz a ti o n * i d a il y p e rc e iv e w o rk p le a su re i n m y w o rk s co re s d s ta ff a employees’ qualities , , , ** , ** , ** , ** , ** a composition of employees , , , ** , ** , ** , ** , ** a work attitude employees* , , , ** , ** , ** , ** , ** a attention for craftsmanship , , , ** , ** , ** , ** , ** a personal goals employees (their aspirations) , , , ** , ** , ** , ** , ** m a n a g e m e n t st y le b qualities of management , , , ** , ** , ** , ** , ** b style of management , , , ** , ** , ** , ** , ** b offered challenges , , , ** , ** , ** , ** , ** b attention to new ideas , , , ** , ** , ** , ** , ** b balance between what the organizations wants and what the employee wants to achieve , , , ** , ** , ** , ** , ** s y st e m c alignment of activities in our organizations , , , ** , ** , ** , ** , ** c our house style* , , , ** , ** , ** , ** , ** c freedom ( autonomy) to decide how to do we perform our work , , , ** , ** , ** , * , ** c informed about what is happening in our organization , , , ** , ** , ** , ** , ** c alignment between management and employees , , , ** , ** , ** , ** , ** c u lt u re d business approach (‘this is how we work here’) , , , ** , ** , ** , ** , ** d rituals like ceremonies, language, manners and jokes , , , ** , ** , ** , ** , ** d attitude towards our environment , , , ** , ** , ** , ** , ** d all work towards the same goals , , , ** , ** , ** , ** , ** d working atmosphere in our organization , , , ** , ** , ** , ** , ** s tr a te g y e products and / or services , , , ** , ** , ** , ** , ** e image* , , , ** , ** , ** , ** , * e mission statement , , , ** , ** , ** , ** , ** e organization goals , , , ** , ** , ** , ** , ** e contribution to society , , , ** , ** , ** , ** , ** e contacts with our environment , , , ** , ** , ** , ** , ** s tr u ct u re f workplace* , , , ** , ** , ** , ** , ** f interior or decoration of my work environment , , , ** , ** , ** , ** , ** f our (internal) cooperation , , , ** , ** , ** , ** , ** f opportunities for my development and deployment , , , ** , ** , ** , ** , ** f everything in my organization is nicely in balance * = reversed question ** = sig < , , , , ** , ** , ** , ** , ** table . overview data aesthetic appreciation of oas and correlation with outcomes part | empirical studies appreciation of oas the appreciation of the oas both within the same organization as well as between organizations exhibits great coherence. employees’ qualities are the highest or second highest appreciated organizational aesthetic stimuli (oas) in all five organizations. organization goals and products and services score within the top- of highest appreciated oas in four of five organizations. almost the same applies to the appreciation of employees‘ work attitude, their goal achievement, work atmosphere (culture), organization mission, the contribution the society and development opportunities score within the top of highest appreciated oas in three of five organizations. overall, employee’s qualities, products / services, goals, contribution to society, work ethics, goal achievement of employees, work atmosphere (culture) and mission are the highest appreciated oas. the alignment of activities is the lowest or second lowest appreciated organizational aesthetic stimulus (oas) in all five organizations. also the way of being informed (internal communication) and alignment of management and employees score within the top of lowest appreciated oas in all five organizations. in four of five organizations balance between organizations goals and individual goals, organization rituals, and the coherence of ‘things’ all score within top of lowest appreciated oas. in three of five organizations style of management and internal cooperation score within top of lowest appreciated oas. it is striking that the standard deviation of almost all outcomes is very low, although it concerns the scores of different organizations with all their own interpretation and of the oas. the appreciation for oas such as products and services, qualities and goals of employees, organizational mission and goals, contribution to society shows a standard deviation < . in terms of the organization design parameters of the esh-model like proposed before, the design parameters staff and strategy shows the highest scores. it should be noted that all design variables show relatively high scores. this can be explained since all surveyed organizations participating in this study have assumed that they would score relatively positive after the items were considered before scoring. relationship appreciation of oas with affective commitment and with aesthetic value initially was examined to what extent there is a relationship between the set of oas and the outcomes of organizational aesthetics (work pleasure, pride, flow-experience, ‘beautiful work’ and a grade for beauty of the organization, see table . and appendix ). but this first correlation analysis only examined the relationship between individual variables. two canonical correlation analyses (cca) were conducted to examine the relationship between the set of oas (resulting in aesthetic experiences) and the phenomena of affective commitment and aesthetic value which are composed of several dependent variables. so actually, this analysis examined the relationship between the components of the lower part of the organizational framework which was used for the empirical studies. both analyses resulted in three canonical functions owing to the number of variables. the results of the analysis are expressed in appendix . the first function of the first canonical correlation between aesthetic experience and affective commitment (see figure . ) represents the optimal linear combinations of dependent variables and the canonical correlation coefficient representing the relationship between them. this relationship is strong, regarding their correlation (. ). the significance tests show a very high level of confidence (. ) in the results. by examining the canonical loadings of both two sets, the predictor variables can be determined. these loading would be . and above to determine strong correlation (hair, et al., ). for set all oas show a loading between . and . with most strong loadings (>. ) for style of management, offered challenges, alignment between management and employees, business approach , organization rituals, attitude towards our environment, all work towards the same goals, working atmosphere, and coherence of things. for set also all dependent variables part | empirical studies show loadings >. with affective commitment. dependent variable pride shows the strongest (canonical) correlation with affective commitment (. ). finally redundancy was examined. the redundancy coefficient expresses the relation between individual measured variables of a set with the variance of variables of the other set. for this analysis, the relation is relatively strong (cv - : . ). figure . relationship aesthetic experience with affective commitment the second canonical function of this first relationship (see figure . ) shows a different result. this canonical function represents a second unique and independent relationship between the dependent variables (flow, pride and work pleasure) and independent variables (oas ). only three of oas show a canonical loading >. with set , which are balance between organization goals and employee goals (b ), internal communication (c ), and organizations image (e ). these oas all concern system aesthetics and the relationship might be interpreted as an awareness and understanding of organizational transparency which in particular contributes to the pride of employees. figure . relationship aesthetic experience with affective commitment the third canonical function of this first relationship (see figure . ) shows another and unique result. only one oas shows a canonical loading >. with set , which is contribution to society (e ). also this oas concerns system aesthetics and the relationship might be interpreted as goal congruence also contributing to proud employees resulting in a good personal-organization fit. figure . relationship aesthetic experience with affective commitment oasa aesthetic experience affective commitment . . flow (g ) work pleasure (g ) . . - . pride (g ) oasf set set . oas… oasa oas… aesthetic experience affective commitment -. . . flow (g ) work pleasure (g ) . -. - . pride (g ) oasf set set oasa oas… aesthetic experience affective commitment , , -, flow (g ) work pleasure (g ) , -, - , pride (g ) oasf set set part | empirical studies the second canonical correlation analysis was conducted to examine the relationship between the set of oas (resulting in aesthetic experiences) and other outcomes, directly related to aesthetic value, represented by the outcomes judgment ‘beautiful work’, judgment ‘beautiful organization’ and ‘attention to organizational aesthetics contribute to performance’. the results of this second analysis are also expressed in appendix . figure . relationship aesthetic experience with aesthetic value the first function of this second canonical correlation (see figure . ) represents the optimal linear combinations of dependent variables and the canonical correlation coefficient representing the relationship between them. this relationship is strong, regarding their correlation (. ). the significance tests show a very high level of confidence (. ) in the results. by examining the canonical loadings of both two sets, the predictor variables can be determined. for set all oas show a loading between . and . with most strong loadings (>. ) for style of management, business approach , attitude towards our environment, all work towards the same goals, working atmosphere, internal cooperation and coherence of things. for set also all dependent variables show loadings >. with aesthetic value. beautiful work shows the strongest correlation with aesthetic value (. ). also redundancy was examined. for this analysis, the relation is relatively strong (cv - : . ). noteworthy is the very strong canonical correlation between aesthetic value and the (perceived) effect on performance. this amounts to . . this confirms the premise that affective commitment contributes to organization performance (e.g. meyer et al., ; meyer et al, ; allen et al., ; meyer smith, ; rhoades et al., ). the second canonical function of this second relationship (see figure . ) shows a different result. this canonical function represents a second unique and independent relationship between the dependent variables (beautiful organization, beautiful work and attention to aesthetics contributes to performance) and independent variables (oas ). only four oas show a canonical loading >. with set , which are balance between organization goals and employee goals (b ), internal communication (c ), organizations image (e ), and coherence of things (f ). the first three oas also show a canonical loading >, with set of the first canonical correlation between aesthetic experience and affective commitment (see figure . ). these oas all concern system aesthetics and the negative loading (-, ) for beautiful organization in relation to these oas is hard to explain. most of the oas concerning organizational coherence and transparency such as work towards the same goals (d ) and alignment between management and employees (c ) all show high canonical loading in the first function of this relationship. it might be interpreted that transparency contributes to the perception of beautiful work, but also could affect the awareness of ugliness in organization aspects. oasa oas… aesthetic experience aesthetic value . . . beautiful work (g ) beautiful organization (o ) . . - . attention to aesthetics contributes to performance (g ) oasf set set part | empirical studies figure . relationship aesthetic experience with aesthetic value the third canonical function of this second relationship does not show canonical loadings for oas >. . the significance of this third canonical function is . which is too low to determine a reliable conclusion. thus considering these results of this analysis, organizational aesthetics (experiencing aesthetic value) can be considered as the promise to affective commitment as well as to performance . a hypothesis for future research could be that organizational aesthetics directly as well as via affective commitment contributes to better performance. oasa oas… aesthetic experience aesthetic value -. . . beautiful work (g ) beautiful organization (o ) . -. - . attention to aesthetics contributes to performance (g ) oasf set set part | empirical studies influence of personal characteristics on aesthetic judgment by conducting a cluster analysis (see table . ) the aesthetic judgment of oas was related to their personal characteristics such as age and educational level. after profiling the found clusters (see appendix ), three types of personal characteristics show a significant strong deviation from the mean scores, which are women (v ), with age - (v ), and - years company tenure (v ). this group concerns respondents ( %). the aesthetic judgment of all oas of this group is significantly lower. anova sum of squares df mean square f sig. v between groups . . . . within groups . . total . v between groups . . . . within groups . . total . v between groups . . . . within groups . . total . v between groups . . . . within groups . . total . v between groups . . . . within groups . . total . v between groups . . . . within groups . . total . table . cluster analysis role of personal characteristics on aesthetic judgment often mentioned oas finally respondents were asked to register what they experience as beautiful and ugly in their organization. this was done for testing the completeness of the list of oas acquired during the first empirical study in which only managers were interviewed. respondents registered oas in which they experience beauty (see appendix ). most frequently mentioned oas are development opportunities ( % of mentioned beautiful aspects in work or organization), colleagues ( %), collegiality / cooperation ( %), culture ( %), autonomy / independence ( %) and workplace (interior / exterior) ( %) and contacts with clients ( %, particularly high ( %) at rabobank woudenberg). interesting is whether the list of mentioned oas of the first study exhibits saturation and is similar to the list of this second study conducted among a much larger group of respondents. the top- of most mentioned oas in both studies is quite similar although the sequence of oas is part | empirical studies different. but is can be determined that the list of oas of the first empirical study shows a sufficient degree of saturation. two often mentioned oas in the second study (‘opportunities in work’ and ‘autonomy’) were added to the survey of this second study based on literature research. two other often mentioned oas in the second empirical study (‘variety of work’ and ‘my work’) were not mentioned by respondents in the first study and should be added to a new list of oas for research in future. considering both lists of often mentioned oas it seems that respondents distinguish two categories of oas: ) oas concerning organization design and ) oas concerning their work. therefore the next studies will more focus on aesthetic experiences perceived during work. respondents registered oas in which they experience ugliness. most frequently mentioned ugly oas are autonomy / independence ( % of mentioned ugly aspects in work or organization), workplace (interior / exterior) ( %), attitude of colleagues ( %) and internal communication ( %). inertia and quality of decisions and workplace (interior / exterior) are often relatively mentioned by umcg-employees. rabobank woudenberg relatively often mentioned autonomy / independence as being ugly in their organization. the categories of ugly oas differ from the list of oas. ugly aspects of the organization mentioned by more than three of five organizations are mainly aspects of management (like their focus of finance / cuts, professionalism management, contact with / access to management and attitude of management / hierarchy), inertia and quality of decisions, not supporting ict / tools, organization size and staff composition. these oas don’t have a mentioned ‘equals’ at the beauty side of organizations. lessons learned of this second empirical study two major lessons learned could be determined .this second study provides a great understanding of the outcomes of attention to organizational aesthetics. due to the canonical correlation analyses can be determined that aesthetic experiences (triggered by oas) are the promise to aesthetic value, to affective commitment and even to performance. second, personal characteristics of employees need to be taken into account during applying and exploiting aesthetic value in organizations. in particular the group of women, age of - , and with - years company tenure show a deviant aesthetic judgment of oas. based on the first two empirical studies, the main boxes of the proposed organizational aesthetic framework (like form, aesthetic process and affective commitment) and its connections are covered. a third empirical study is needed to examine oas experienced during work (i.e., process). part | empirical studies . . study : aesthetic experiences in events research objectives the first two empirical studies both provide insight in oas which trigger employees’ aesthetic experiences. this list of oas can be divided into oas concerning organization design parameters such as organization goals (system aesthetics and result aesthetics) and oas concerning work design parameters (process aesthetics) while for the latter category not particularly was requested. so, the research objectives of this third empirical study were (i) to examine positive aesthetic experiences (paes) of employees in their work, and conditions for these experiences, and (ii) to test in a pilot whether respondents are able to register these aesthetic experiences by using self- reports. methodology research context this third empirical study was needed to specifically respond to the aesthetic experiences of employees during their work, the so-called process aesthetics. the focus of this empirical study was to gather daily paes during work of professionals what resulted in about registered aesthetic experiences. data sources six employees, high qualified and knowledge workers ( people from organizations: three employees of three organizations and three employees of one organization) were asked for two weeks to daily register - paes. these respondents were recruited in the immediate vicinity of the researcher. although these respondents daily perform work which can be characterized as work of professionals, they were in particular selected because of their willingness to daily register paes for two weeks and to participate in a pilot-study (pilot for the fourth empirical study). measures a lesson learned from both first empirical studies was that the level of detail of the description of an organizational aesthetic stimuli (oas) was in many cases very low. respondents often mentioned one word such as cooperation or management. therefore, in this third empirical study self-reports were used to collect aesthetic experiences of employees, allowing a more rich description of the stimulus as well of the aesthetic process is obtained. self-reports are increasingly used to collect daily experiences (e.g. robinson and clore, ; grandey et al., ; sørensen, ; sandelands and buckner, ). by using the method of self-reporting (a bel-book: beauty experience log book), six respondents were asked to register daily their aesthetic experiences (ugly and beautiful) for a period of ten working days. in this self-report, respondents were also asked to make a top- list of most beautiful and most ugly aesthetic experiences (process aesthetics), to describe the conditions necessary for the positive aesthetic experiences, to make a top- list of most beautiful and most ugly aspects of their organization and to appreciate the process aesthetics and organizational aesthetics of their organization by giving a grade ( - ). the respondents were also asked by email to register their remembered aesthetic experiences (about the same period they daily registered their experiences in the bel-book) three months later. this was examined to investigate whether aesthetic experiences with short term impact can be distinguished from these with long-term impact (e.g. steinkraus, ; cupchik and laszlo, ; leder et al., ) and to determine whether the psychological mechanisms familiarity and prototyping affects employees’ aesthetic experiences (e.g. kunst-wilson and zajonc, ; winkielman, schwarz, fazendeiro and reber, ; mastandrea, bartoli and carrus, ; leder et al., ). the period of three months was chosen because of the major time effort the part | empirical studies respondents experienced earlier for registering their paes and naes. to ensure the validity and reliability of this empirical study, some measures were taken at the start of this third study. because strict replication of this a study by another researcher is usually not possible, another criterion for securing reliability is that the research process is traceable (van burg, ). therefore a protocol was developed for how to use the bel-book. to ensure validity the survey was completed by respondents of different organizations in order to examine whether results could be generalized. in addition, by using codes used in the first empirical study, it provides comparability of data with the first study. analytical approach the qualitative data was manually coded (selective coding, based on the defined categories of oas after the first and second empirical study) supplemented with often used categories of events of basch and fisher ( ). this was preceded by a cross-case analysis. given the large number of paes we took a progressive approach by considering codes that were mentioned by at least % of respondents. secondly, after coding, the obtained data was categorized according the five parameters of the esh model (system, employees, management style, structure, culture, strategy). results positive aesthetic experiences (paes) paes of respondents from different organizations were collected (see table . and appendix ). the respondents experience a high degree of aesthetic value in interaction with others ( %). dependent of the type of work, highly appreciated is the interaction with colleagues ( %), but also the interaction with customers ( %), and managers ( %). furthermore, goal progress and goal achievement ( % versus %) is often experienced as beautiful as well. also, learning and ‘being positively surprised’ are considered as beautiful ( %) as well as the experiences of receiving appreciation and recognition ( %). part | empirical studies categories of events (basch and fisher, ) p e rc e n ta g e m e n ti o n e d b y n u m b e r o f re sp o n d e n ts (t o ta l ) p e rc e n ta g e a ft e r - m o n th s (t o p - ) ) goal achievement % % % ) receive recognition and appreciation % % % ) interaction with of colleagues % % % ) involvement in challenging tasks / opportunities % % % ) acts of customers % % % ) interacting with customers % % % ) goal progress % % % ) organizational reputation % % % ) disconfirmation of negative expectations % % % ) involvement in decision making % % % ) influence or control % % % ) involvement in planning % % % ) interaction with management % % % ) other % % % added events ) learning, intellectual challenge, be surprised and come to an understanding % % % ) weather % % % table . overview scores on categories of events the respondents were also asked to register a top- of most beautiful events in two weeks to be able to distinguish in possible preferences for types of oas. four respondents mention the interaction with colleagues on the first or second place in this top- list. categorizing this data according to fisher ( ) and basch’s events, much similarity is perceptible, certainly regarding the categories of goal achievement, goal progress, acts of colleagues, customers and management, challenging tasks and influence or control (autonomy). despite the low degree of similarity between collected experiences, they all experienced goal achievement, interaction with colleagues, and goal progress as beautiful. out of respondents perceive ‘receiving recognition’ and ‘interaction with customers’ as beautiful. positive aesthetic experiences (paes) after - months the collected experiences were daily registered at the end of the day. for considering the long- term impact of aesthetic experiences the respondents were asked after - months to register their remembered aesthetic experiences (beautiful and ugly) of the period they used the bel-book ( - months before). % of respondents cited events (total of ) they didn’t mention before, but most respondents show a strong similarity with the type of events they mentioned - months before. part | empirical studies although in most cases it concerned other events, the mentioned type of events show strong similarity like interaction with customers or match recognition and appreciation. for example, one respondent initially mentioned some contacts with colleagues as part of recognition and appreciation. three months later he ´remembered´ in particular ´a gift of a manager´ representing this same type of event, which he didn’t mentioned before. another example is a respondent who initially registered many conversations with colleagues. after three months she mentioned one remarkable conversation she didn’t register earlier. this result can be explained by the psychological mechanisms of familiarity and prototyping. apparently respondents feel familiar with these events (kunst-wilson and zajonc, ; winkielman, schwarz, fazendeiro and reber, ) and prototype these events as representative of a class of aesthetic experiences (leder et al., ). the respondents were also asked to value their appreciation for as well as their experienced beauty in the events and the organizations aspects. although it relates only to the scores of six respondents it is remarkable that they all give a higher value for the beauty they experience in the daily events than in their organizational aspects: average score . versus . . lessons learned a first lesson learned is that respondents seems to be sufficiently capable to use the bel-book. the registered experiences of respondents are described more extensive and colorful and they show an equal level of detail. respondents seem to be quite capable to reflect retrospectively on their aesthetic experiences and to describe them. therefore, the method can be considered as a useful new tool for collecting aesthetic experiences. a second lesson learned is that aesthetic experiences observed during events (process aesthetics) can be distinguished from experiences observed in oas in organization aspects (system aesthetics). process beauty seems to be higher appreciated. they experience a high degree of beauty in interaction with others, especially with colleagues, and in concern with the realization and achievement of goals (goal progress and achievement). these oas are missing on the list of oas which was used in the second empirical study and they should be added to get a complete list of oas. categorizing the data according to basch and fisher’s events (basch and fisher, ) show much similarity in type of events, certainly as regards the categories of goal achievement, goal progress, acts of colleagues, customers and management, challenging tasks, and influence or control (autonomy). which proves that emotions owing to aesthetic experiences are quite similar to most common emotions in organizations, which can be considered as a third lesson learned. a fourth lesson could be assessed. all collected oas trigger aesthetic experiences to some extent and all respondents seem to be quite capable of designate a top- of aesthetic experiences. but an explanation why respondents rank their aesthetic experiences can still not be given. it is very likely that not only the aesthetic judgment (beautiful - ugly) affects the final judgment of the perceiver, but also the emotional impact of an aesthetic experience (russell, weiss and mendelsohn , ; russell, ward and pratt, ; watson, clark and tellegen, ). therefore, the bel-book which was used during the fifth empirical study was extended with the measurement of the emotional impact. finally, employees get used to the presence of oas or at least to the type of events they represent. their aesthetic appreciation slowly decreases over time apparently affected by some psychological mechanisms such as familiarity and prototyping (kunst-wilson and zajonc, ; winkielman, schwarz, fazendeiro and reber, ). so, a last lesson learned is the importance of the attention of the role of time by examining aesthetic experiences in organizations. part | empirical studies . . study : the role of position and time to aesthetic judgment research objectives the first three empirical studies have clearly given first indications of objects of work and organization which cause paes and naes to employees. in particular the second and third study have shown that time affects aesthetic judgment of employees, which is confirmed in literature on aesthetics (e.g. leder et al., ; brickman et al., ). for example, by using the bel-book by employees for registering aesthetic experiences in the third empirical study, employees became more consciousness of their aesthetic awareness and needs. the bel-book forced them to reflect again on the aesthetic stimuli in their environment. an interesting result of the second study was that new employees (newcomers) show a higher aesthetic judgment to oas than employees who worked for a longer period. this was designated as a "nostalgia effect". this effect concerns a short peak in happiness, after which people become accustomed to the stimulus (brickman et al., ). people become familiar with oas, which affects aesthetic induction and prototyping of aesthetic experiences (e.g. mastandrea, bartoli and carrus, ; kunst-wilson and zajonc, ; leder et al., ). being confronted with another context and comparing aesthetic stimuli possibly increases the aesthetic awareness as well as affects the aesthetic judgment for oas (e.g. brickman et al., ; king and wertheimer, ; leder et al., ). so, the major aim of this study is to examine the role of organizational aesthetics in returning to an employer. methodology research context to examine the role of time as well as the role of position towards oas, employees were interviewed who returned within a period of the last years to a previous employer. these respondents were hard to find and were recruited via calls via twitter and linkedin. data sources to examine why employees returned to an employer and what the differences were between paes and naes in organization and , employees were interviewed. interviews, using an interview protocol with open questions (see appendix ), offer the possibility to comprehensively reflect on answers and to directly respond to them. the transcripts of the interviews were approved by the respondents (member check) (van burg, ). measures respondents were asked to compare the oas of both employers and to define which oas they became more aware of after returning and how these new encounters influenced their aesthetic judgment (e.g. brickman et al., ; king and wertheimer, ). these questions were asked using an interview protocol with open questions (see appendix ). analytical approach the obtained interview data was manually coded (selective coding, based on the defined categories of oas of other empirical studies). this was preceded by a cross-case analysis. given the limited number of interviewees and the exploratory nature of the study we took a conservative approach by considering codes that were mentioned by at least out of employees. secondly, after coding the obtained data was categorized according to the five parameters of the esh model (system, employees, management style, structure, culture, strategy). results respondents experienced naes aspects in their new organization (see appendix ). these are organization goals ( %, dominant focus op finance), organization’s philosophy ( %), style of part | empirical studies management ( %) and other aspects ( %). respondents experienced paes in the organization they returned in support of management (management style, %), culture ( %), involvement / solidarity colleagues (culture), interior / exterior and work (all %) and other aspects ( %, mentioned more than once: x aspects of system, x aspects of culture). the main reasons for returning to their former employer are style of management ( %) and colleagues ( %). of respondents recognized a new employer as a new frame of which employees became more aware of the degree of beauty of their previous employer. none of them called new beautiful aspects other than what they previously denoted as beautiful in their former organization. culture and management style are mentioned by of respondents as aspects of which one became more aware of its beauty after one experienced elsewhere. lessons learned first of all, it was hard to find employees who returned to a former employer. but after finding, they were quite able to speak out why they left and returned to an employer. although respondents specifically were asked about what was beautiful and ugly about their two employers, possibly a sort of attention bias could be applied. respondents particularly talked about the differences between two employers, and not specifically about aesthetic aspects. but nevertheless, this small empirical study proved that employees get used to beauty and ugliness in their organization. and by confrontation with a new employer (variation of environment), the employee becomes more conscious of the oas in his former organization. so, lesson learned is the importance of attention of the role of position of the employee by examining aesthetic experiences in organizations. part | empirical studies . . study : aesthetic experiences of professionals research objectives the first four empirical studies focused on aesthetic experiences and judgments of general employees of professional organizations. this study focused on the question of what aesthetic experiences professionals have during their daily work, what conditions are needed for having these experience (i.e., what the drivers are), and which profits they consider for them and for the organization. we have chosen for a limited group of professionals, namely surgeons and teachers of elementary schools. both types of employees both perform professional labor (which is the most important target group of this dissertation) in different contexts (e.g. wilson, ; peterson, ; casell et al., ); dwarswaard, ). a second aim of this last empirical study is to collect associations of respondents with formal properties (such as balance, repetition, and symmetry). all six oas representing this type of aesthetic property correlate (canonical) remarkably high with affective commitment in the second empirical study. it is very likely that this earlier collected set of oas is not covering all conceivable formal properties. methodology research context the focus of this fifth empirical study is to gather daily aesthetic experiences (positive aesthetic experiences: paes and negative aesthetic experiences: naes) during work of professionals. data sources also in this study the bel-books were used to gather data. it can be considered as a repetition of the third empirical study, but now focused on the target group professionals. ten respondents were asked for two weeks to daily register - paes en - naes what will result in about registered aesthetic experiences. five teachers from two elementary schools and five surgeons of two hospitals registered for weeks in their paes and naes. these teachers and surgeons were selected in the immediate vicinity of the researcher. the willingness to participate was a more important criterion than all kinds of personal characteristics of respondents. measures for collecting aesthetic experiences of professionals the same method for collecting was used as in the third empirical study. this method, self-reports in particular the bel-book, proved to be a reliable and valid method. this bel-book was completed with an affect grid for measuring respondent’s aesthetic judgment as well as the emotional impact. together they affect perceiver’s emotion and the durability of an aesthetic experience (russell, weiss and mendelsohn , ; russell, ward and pratt, ; watson, clark and tellegen, ). in this affect grid (based on russell, weiss and mendelsohn, ) respondents ranked their aesthetic experience on a scale of beautiful to ugliness (x-ax) and on a scale of high versus low emotional impact (y-ax). this method of valuation was added to get more discrimination in beauty ratings. figure . shows an example of a collected positive aesthetic experience (pae) and an example of negative aesthetic experience (nae). part | empirical studies day positive aesthetic experience (pae) b e a u ti fu l high emotional impact u g ly m . mr. k. called to thank me for guidance in a difficult and complicated treatment, he recovers well and is sporting again x low emotional impact day negative aesthetic experience (nae) b e a u ti fu l high emotional impact u g ly l . mrs. ade will leave. how will it continue? apparently, a new director, a real person ..... no transition, i worry .......... vision or urge retention? x figure . examples of registered pae and nae)in the bel-book low emotional impact in addition, an open-ended question was added for collecting first associations with formal properties (like unity, harmony, and balance) to have a richer understanding of the interpretation of these important aesthetic properties. this was done because all measured formal properties showed a very strong correlation with the final grade for organization beauty in the second empirical study. in order to ensure the validity and reliability of this empirical study, we developed a survey in which the selected oas are categorized according to the parameters of the esh model (structure, culture, employees, management style, strategy, and system. this arrangement creates of form of consistency. because strict replication of this study by another researcher is usually not possible, another criterion for securing reliability is that the research process is traceable (van burg, ). therefore a protocol was developed for how to use the bel-book, like was done in the third empirical study. analytical approach the qualitative data was manually coded (selective coding, based on the defined categories of oas after the previous empirical study) supplemented with often used categories of events of basch and fisher (basch and fisher, ). this was preceded by a cross-case analysis. given the large number of paes we took a progressive approach by considering codes that were mentioned by at least % of respondents. secondly, after coding the obtained data was categorized according to the five parameters of the esh model (system, employees, management style, structure, culture, strategy). part | empirical studies results . teachers elementary schools aesthetic experiences teachers (paes and naes) five teachers from two elementary schools registered for weeks in total paes and naes. % of the paes concern the experience of beauty of a result (see figure . : goal achievement, of which % are slightly off, something to achieve). followed by acts of customers ( %, in particular students and to a lesser extent, parents of students), the interaction with them ( %, interaction with customers), contacts with colleagues ( % interaction with colleagues), receiving recognition ( %) and aesthetic experience of goal progress, in particular those within the classes ( % goal progress) interaction with colleagues ( , ), interaction with students / parents ( . ), goal achievement ( . ) and acts of students ( , ) are the highest rated events (aesthetic judgment x emotional impact). figure . overview of paes and naes teachers looking at the paes expressed in the affect grid in the bel-books (degree of beauty and degree of emotional impact, see figure . and appendix ), goal achievement scored the aesthetic judgment ( out of respondents). act or customers scored the highest emotional impact related to the paes ( out of respondents). the highest score of paes for judgment x emotional impact concerns goal achievement ( out of respondents). part | empirical studies figure . overview scores paes and naes of teachers respondents were also asked at the end of the registration period to draw a top- to of paes (see table . ) . act or customers (particularly acts or students) was mentioned most often ( out of respondents), followed by interaction with colleagues ( out of respondents). it is remarkable that particular events are listed that show a relatively high emotional impact score. with regard to the naes, a similar statement of these is expressed. % of naes of teachers concern a lack of control or influence, % concern an ugly outcome (less of no goal achievement, of which % barrier in achieving tasks or goals), % concern the interaction with customers (students and parents or students), followed by interaction with colleagues ( %) and acts or customers ( %). when looking at the naes expressed in the affect grid, lack of control or influence scores lowest in terms of aesthetic judgment ( out of respondents). also regarding highest emotional impact and emotional x judgment, lack of control or influence show the highest scores ( out of respondents). the top- of naes respondents noted at the end of two weeks, for both the lowest aesthetic judgment and the highest emotional impact and judgment x emotional impact show a varied picture. part | empirical studies often mentioned paes / naes in work highest appreciated paes (aesth.judgxemotion, max = ) paes: . goal achievement ( %) . acts of students ( %) . interaction with students / parents ( %) . interaction with colleagues ( %) . receiving recognition ( %) . goal progress ( %) naes: . no or less influence or control ( %) . no or less goal achievement ( %) . negative interaction with customers ( %) . negative interaction with colleagues ( %) . negative acts of customers (students and parents) ( %) . interaction with colleagues ( , ) . interaction with students / parents ( , ) . goal achievement ( , ) . acts of students ( , ) . goal progress ( , ) . receiving recognition ( , ) . acts / interaction with management ( , ) . influence or control ( , ) . involvement with challenging tasks ( , ) . other ( , ) ranking paes (top- paes): . act of customers ( %+) . interaction with colleagues ( %+) . goal achievement ( %) . other ( %) . interaction with customers ( %+) . receiving recognition ( %+) % = % mentioned by respondents in top- + = mentioned times or more by one respondent table . overview of scores of teachers . surgeons aesthetic experiences surgeons (paes and naes) five surgeons from two hospitals registered for weeks in total paes and naes. % of the paes concern the experience of beauty of a result (goal achievement), mainly mentioned in relation to an operation or treatment of a patient. also often registered paes are contacts with colleagues ( % interaction with colleagues), acts of customers ( %) and goal progress ( %) (see figure . ). receiving recognition, goal progress, interaction with colleagues and goal achievement are the highest rated events (aesthetic judgment x emotional impact). looking at the paes expressed in the affect grid in the bel-books (degree of beauty and degree of emotional impact), goal achievement scored the highest aesthetic judgment ( of respondents). also goal achievement scored the highest emotional impact related to the paes ( of respondents). the highest score of paes for judgment x emotional impact concerns also goal achievement ( out of respondents, see figure . and appendix ). respondents were also asked at the end of the registration period to draw a top- to of paes. interaction with colleagues was mentioned most often ( of respondents), followed by goal progress ( of respondents), receive recognition and act of customers(both of respondents). it is remarkable that most of these events show a relatively high emotional impact score. part | empirical studies often mentioned paes / naes in work highest appreciated paes (aesth.judgxemotion, max = ) paes: . goal achievement ( %) . interaction with colleagues ( %) . acts of customers ( %) . receiving recognition ( %) . goal progress ( %) . interaction with customers ( %) naes: . bad interaction with colleagues ( %) . no or less goal achievement ( %) . no or less influence or control ( %) . no or less involvement with planning ( %) . bad acts of customers ( %) . no or less goal progress ( %) . bad stimulus from physical environment ( %) . receiving recognition ( . ) . goal progress ( . ) . goal achievement ( . ) . interaction with customers ( . ) . interaction with colleagues ( . ) . involvement with planning ( . ) . acts of customers ( . ) . stimulus from physical environment ( . ) . influence or control ( . ) . involvement with challenging tasks ( . ) . other ( , ) . involvement with decision making ( . ) . acts / interaction with management ( . ) . not-functioning ict ( . ) ranking paes (top- paes): . interaction with colleagues ( %+) . goal progress ( %+) . receive recognition ( %+) . act of customers ( %+) . goal achievement ( %+) . other ( %) . acts of customers ( %) . acts of management ( %) % = % mentioned by respondents in top- + = mentioned times or more by one respondent table . overview of scores of surgeons with regard to the naes, a similar statement of these is expressed. % of naes of surgeons concern a bad or no interaction with colleagues, % concern a bad or no result (goal achievement) as well as for paes concerning an operation or treatment of a patient, % concern a lack of influence or control, mainly in relation to work planning or decisions of management, followed by a lack of involvement by planning ( %). bad or no interaction with colleagues (- , ) and a lack of influence or control (- , ) are the highest rated naes (aesthetic judgment x emotional impact). looking at the naes expressed in the affect grid, less or no goal progress, like the paes for surgeons, scores lowest in terms of aesthetic judgment ( out of respondents). also regarding highest emotional impact and highest emotional impact and emotional x judgment, less or no goal progress show the highest scores ( of respondents versus of respondents). of the top- of naes respondents noted at the end of two weeks (see table . ), bad interaction of colleagues followed by less or lack of goal achievement are most mentioned. both score relatively high on emotional impact. part | empirical studies figure . overview of paes and naes surgeons figure . overview scores paes and naes of surgeons part | empirical studies this study and the third empirical study have provided insight in oas particular experienced in events during human action. in comparison with the already acquired list of oas (as a result of the first and second empirical study) some new stimuli (oas) should be added. criteria for adding these oas were the extent to which they have been mentioned by respondents (> %) and the degree of aesthetic appreciation x experienced emotional impact of oas (>+/- ). based on this criteria goal achievement, receive recognition, goal progress should be added to the list. the oas interaction with colleagues, acts and interaction with customers, and influence or control (including involvement with planning) were already part of the list compiled after ending the second empirical study (represented by respectively internal cooperation, contacts with our environment and autonomy). formal properties and professionals the two groups of professionals were also asked to register formal properties. because of the strong (canonical) correlation of these properties with ‘aesthetic value’ in the second empirical study as well as in the fifth empirical study on professionals, a first notion arose that formal properties in organization design also are important stimuli for aesthetic experiences, like in other disciplines such as architecture and product design in which aesthetics have an important role. the correlating six formal properties were mentioned in the interviews in the first empirical study or were found in literature. the successful scores of these properties raise the questions whether those six formal properties represent the most common formal properties in organizations. therefore, professionals were asked to associate most common formal properties (eleven in total, e.g., harmony, variety, climax, and grouping) considered in the arts with aspects of their work and organization. the results are expressed in the overview in appendix . this overview shows some interesting results. first, the associations differ per group of professionals. only grouping, harmony and to a lesser extent symmetry, unity, and repetition / rhythm are quite similar associated by both groups. grouping is mainly associated with colleagues, harmony is synonym for harmony within a group of colleagues and symmetry is mainly associated with the building in which they work. unity is strongly related to unity within the team they work and repetition / rhythm is highly associated with work and work schedules. second, similar associations within the same group are work-life balance (balance associated by surgeons) and doing surgery and operate (climax associated by surgeons). comparing these results with most mentioned formal properties by others in the first and second empirical studies and with most cited formal properties after literature search on most leading journals in the field of organization studies, a few similarities are to discover. the mentioned associations by surgeons and teachers are almost all mentioned in the literature search. but none of these six formal properties (which were selected for the survey) were mentioned by respondents in the first and second empirical studies. thus, formal properties as part of oas are important triggers for aesthetic experiences in organizations. which formal properties in particular affects aesthetic experiences seem too specific for audience and context and need to be examined in future. lessons learned this last empirical study resulted together in paes and naes of teachers and surgeons. the main conclusion of this study is that aesthetic experiences of professionals must be distinguished from those of general employees of professional organizations which were examined in the first three empirical studies. the type of work as well as the characteristics of the organizations, in particular the degree of dependence of support from the organizations for performance, affects the oas which trigger aesthetic experiences. second, the bel-book extended with the affect grid can be considered as a useful method for collecting and valuing aesthetic experiences. but its use is time-consuming and requires a lot of part | empirical studies discipline of the respondent. given the fast acting effect of saturation (prototyping of paes and naes a registration period of five working days (instead of ten days) could be considered in future. finally, formal properties such as alignment of activities and alignment of personal goals with organization goals can be considered as strong triggers for aesthetic experiences and strongly contribute to affective commitment of employees. which formal properties in particular affect aesthetic experiences seems to specific for audience and context and needs to be examined in future. arguments for ending empirical research after conducting five empirical studies we decided to end the empirical research. two arguments are the basis for that decision: ) the extent to which research questions were answered; ) the reliability and validity of the research. this empirical research aspired to find out in what stimuli (organizational aesthetic stimuli: oas) employees experience beauty and ugliness (empirical data of the boxes form and work events of the proposed organizational aesthetics framework), to which extent personal characteristics influence aesthetic appreciation (empirical data of the boxes employee and aesthetic process), and to which extent aesthetic experiences are durable (empirical data of the box aesthetic process as well). like argued in the section . research strategy, to collect data on the mechanisms, contexts and outcomes, no specific research methodology is available (gijselinckx, ). gijselinckx advocates a methodological eclecticism in which both quantitative and qualitative research methods are used to achieve the necessary triangulation. an essential question is: how many different methods are needed? an indication of the number of methods may be the moment when the researcher thinks 'now i find nothing new ...'. after five empirical studies, conducted within organizations with contributions of more than respondents and having used a combination of research methods, the moment gijselinckx described has been reached. like urquhart ( ) argued, inductively deriving insights from empirical data engaging with other theories (about aesthetics, organizational design and employee commitment described in the literature research section), design principles for organizational design gradually unfold. part | empirical studies part | empirical studies . discussion . . form, personal characteristics, aesthetic process and affective commitment this discussion is conducted along the parts of the initial organizational aesthetics framework (see fig. . ), which is based on the framework (and its connections) of the affective events theory (aet) in this part of the framework the process of having aesthetic experiences is expressed. the obtained empirical data about this process affect the interpretation of the design causality (value, needs, function, properties and form of the organization), which expresses the upper part of the organizational aesthetics framework. these implications are discussed in chapter . globally, two antecedents for having aesthetic experiences can be considered (e.g. mitias, ; parker, ; parson, ): ) an object / stimulus (organizational aesthetic stimuli: oas) and ) a perceiver (the employee). this object-subject interaction triggers the aesthetic process. the aesthetic process results in an emotion that affects affective commitment, which has been determined as the main effect of attention to aesthetics in organizations. in the proposed organizational aesthetics framework, the object is represented by the box ´form´ and ´affective events´ which will be discussed first. form and affective events triggers for aesthetic experiences form is representing the organization which can be considered - in terms of aesthetics - as a construct (a collection of objects) of organisation design parameters and work design parameters which contains indicators or triggers for aesthetic experiences by employees (subject). an important aim of this dissertation was to examine what stimuli (organizational aesthetic stimuli: oas) in work and professional organization trigger aesthetic experiences of employees and contribute to their affective commitment. the organizational aesthetics framework distinguishes two type op stimuli which triggers aesthetic experiences: ) stimuli perceived in organization design parameters (such as structure, employees together expressed in the components of the used esh model for organization design) and ) stimuli perceived in events and during human action. the empirical studies have resulted in four types of lists of oas. part | empirical studies most mentioned oas in organization aspects highest appreciated oas in organization aspects (on scale of - ) strongest correlating* oas with aesthetic value strongest correlating* oas with affective commitment . interior / exterior (in % of the cases; x) struc . collegiality / cooperation (in % of the cases; x) struc . development opportunities (in % of the cases; x) man . employees (competencies, attitude, ambitions of colleagues; x) staff (in % of the cases) . autonomy / independence (in % of the cases; x) syst . culture (in % of the cases; x) cult . contribution to society (in % of the cases; x) strat . offered challenges / opportunities in my work (in % of the cases; x) man . contacts with customers staff (in % of the cases; x) . variety of work (in % of the cases; x) syst * = canonical correlation, all sig < , . employee’s qualities ( . ) staff . organization goals ( . ) strat . contribution the society ( . ) strat . products and services ( . ) strat . work attitude of employees ( . ) staff . work atmosphere (culture) ( . ) cult . organization mission ( . ) strat . goals of employees ( . ) staff . development opportunities ( . ) man . image ( . ) strat . attitude to environment ( . ) staff . contacts with environment ( . ) staff . working towards the same goals (. ) cult . attitude towards environment (. ) staff . business approach (. ) strat . offered challenges (. ) man . coherence of things (. ) struc . work atmosphere (. ) cult . internal cooperation (. ) syst . alignment between management and employees (, ) syst . development opportunities (. ) man . organization rituals (. ) cult . balance between organization goals and goals of employees (. ) man . organisation mission (. ) strat . work atmosphere (. ) cult . attitude towards our environment (, ) staff . offered challenges (. ) man . coherence of things (. ) struc . business approach (. ) strat . alignment between management and employees (. ) syst . working towards the same goals (. ) cult . internal cooperation (. ) syst . style of management (. ) man . balance between organization goals and goals of employees (. ) man . development opportunities (. ) man table . four lists of organizational aesthetic stimuli (oas) part | empirical studies remarkable are the differences between these four lists (see table . ). when the top- list of strong correlating oas (with ´aesthetic value´ and with ´affective commitment´) is compared with the two top- lists ‘often mentioned' and 'highly appreciated’, only little agreements are to observe. on the basis of a theoretical premise of the aesthetics, one is tempted to call that beauty in something one is interested in (pepper, ; fairchild, ; mitias, ; leather et al., ). the list of the appreciation of oas just shows the appreciation for these aspects in the organizations of the respondents. they do not reflect on the interest or on the intended level of beauty. only the third list, the list of canonical correlations with aesthetic value, shows the potential contribution of aesthetics in organizations. none of the oas of the top- list ‘strongly correlating oas’, accept ‘culture’ (work atmosphere), is part of the top- list of ‘often mentioned'. of the top- list ‘correlating oas’ only ‘work atmosphere’, ‘organization mission’, and ‘development opportunities’, are part of the top- list 'high appreciated’. thus, it is striking that most oas that exhibit a strong correlation with aesthetic value and with affective commitment are relatively low appreciated as well as hardly mentioned in the top- list of ‘often mentioned'. it is further remarkable that oas with strong correlation with both outcomes are not necessarily highly valued. this will be explained in the next paragraph. these single oas can be considered as single objects (as part of a construct, the organization) which cause aesthetic experiences as well as indicators of aesthetic value in organizations. the list of oas (which constitutes the used survey) which was applied in the second empirical study was categorized according to the parameters of the esh model (structure, strategy, employees, system, culture, management style). it can be concluded that all collected oas are equally distributed over these parameters and that aesthetic value not particularly is represented by one of these parameters. beautiful work versus beautiful organizations the work design can be considered as the first circle of impact on aesthetic events. its importance is confirmed in many studies (e.g. baugh and roberts, ; wallace, ; llapa-rodriquez et al, ; parry, ; friedson, ; parry, ). especially professionals feel more committed to work than to their organization (e.g. baugh and roberts, ; wallace, ; llapa-rodriquez et al., ). the traditional classification of hackman and oldham’s ( ) job characteristics model could be used to distinguish the oas from each other (related to job or task design versus to organization design). at least oas such as autonomy, contacts with colleagues, and development opportunities can be easily matched with this classification of task variety, task identity, task significance, autonomy, and job-based feedback. considering the differences in scores for ‘beautiful work’ and ‘beautiful organization’ ( . versus . ) it would be likely that in particular those oas’s representing the cluster of job characteristics model show a strong correlation with the score for ‘beautiful work’. but they don’t. all oas correlate stronger with scores for ‘beautiful organization’. also the results of the conducted canonical correlation analyses offer an understanding of this phenomenon. the set of oas shows a strong (canonical) correlation with the set aesthetic value, represented by ‘beautiful work’, ‘beautiful work’ and ‘attention to organizational aesthetics contribute to performance. the loadings for these variables are . , . and . . which could be interpreted as interweaving of oas (work design parameters and organization design parameters) that strongly contributes to the appreciation of aesthetic value in work aspects. but the second function of this canonical correlation shows that four oas, all organization design parameters, are related to a negative loading for ‘beautiful organization’ but to a positive loading for ‘beautiful work’. so, it is difficult to explain this phenomenon. employees of professional organizations apparently associate oas related to variables of work design with the variables of organization design. work is apparently perceived as beautiful by certain characteristics of the organization. part | empirical studies psychological phenomena during measurement the differences between the lists often mentioned, high appreciated and strongest correlation could be explained by several psychological phenomena. first, studies of lazarus ( ), scherer, schorr, and johnstone ( ) and fisher ( ) show that ‘it is important to remember that positive attitudes are not directly created by environments or events, but rather by individuals’ perceptions, interpretations, and appraisals of those environments and events.’ they refer to the large body of research on appraisal theories of emotion (citing lazarus, ; scherer, schorr and johnstone, ) clearly supports a critical role for the appraisal process in determining experienced emotion. second, aesthetic experiences are triggered by perceptions. perception is not necessarily based on reality, but is merely a perspective from a particular individual’s view of a situation (robbins, ; buelens et al., ). and third, it is likely that combinations of phenomena affect heuristic, mere exposure effect, aesthetic induction, prototyping and familiarity and verbal overshadowing play an important role by mentioning and registering aesthetic experiences. by asking employees what they experience as beautiful and ugly in their work and organization, they possibly will mention aspects which they initially associate with beautiful and ugly aspects in ´normal life’, not work-related. this could be a first explanation why interior / exterior is mentioned in % of the cases. these ‘normal life’ associations are probably functioning as prototypes for their aesthetic categories in their ‘working life’ (leder et al., ). they feel familiar with these and they have a more positive attitude toward stimuli they have seen before (kunst-wilson and zajonc, ; winkielman, schwarz, fazendeiro and reber, ), which could be related to the mere exposure effect (e.g. zajonc, ). by repeatedly questioning employees about their aesthetic experiences, like is done by using the bel-book, probably the phenomena of affect heuristic (zajonc, ) and aesthetic induction (mcallister, ) will appear. employees mentioned and registered those aesthetic experiences that feel comfortable. respondents spontaneously mentioned that they noticed more and more beautiful things in their organization while completing the bel-book. this sort of ‘aesthetic self- fulfilling prophesy’ and attention bias (nisbett and ross, ) could be related to the phenomenon of aesthetic induction. respondents are applying aesthetic criteria based on empirical observations and are inclined to like and use it as the criterion for evaluation. this could be an explanation why in all cases employees appreciate similar oas equally high. finally, also the aspect of verbal overshadowing (melchionne, ; schooler and engstler-schooler, ) seems to be recognized in the collection of aesthetic experiences. even if the phenomena of affect heuristic, mere exposure effect, aesthetic induction, prototyping, and familiarity are not relevant, employees will probably initially mention oas which can be formulated easily. particularly in relation to aesthetic experiences, taylor ( ) introduced the term of aesthetic muteness: the difficulty of expressing aesthetic dimensions of experience in words. this could be a consideration why respondents do not mention aesthetic formal properties - to a lack of meta-language - like coherence of things, represented by oas like alignment of management with employees, alignment of organization goals with individual goals, alignment of activities and the composition of employees, which all show strong correlation with their final judgment of beauty in their organization. they possibly dispose their ‘real judgment’, because it is repressed in what they can express in language. considering these psychological phenomena, a combination of research methods is recommended. only asking employees what they experience as beautiful and ugly isn’t sufficient. only by asking respondents to value their appreciation of mentioned oas as well as to ask their appreciation for revenues of aesthetic experiences like their judgment about beautiful work or beauty in their organization, some of the mentioned psychological phenomena could be recognized and excluded. part | empirical studies functional beauty and dysfunctional ugliness like stated earlier, the most frequently mentioned ugly oas are autonomy / independence, workplace (interior / exterior), attitude of colleagues and internal communication. these oas have their ‘equals’ at the beauty side of organizations. the frequently mentioned ugly oas which don’t have an ‘equal’ in beauty are mainly aspects of management (like their focus of finance / cuts, professionalism management, contact with / access to management and attitude of management / hierarchy), inertia and quality of decisions, not supporting ict / tools, organization size and staff composition. it seems that oas which cause naes express more (dys)functional value than aesthetic value. for example, not functioning ict in schools or bad personal planning and less in control and influence in hospitals can be considered as dysfunctional aspects of an organization as well as they constitute barriers for respondents’ own performance and for often mentioned paes like goal progress and goal achievement. oas that cause naes, seem to be more judged on an ethical basis instead on an aesthetic basis. this confirms the results of a well known research of herzberg, mausner and snyderman ( ) in which they asked employees to describe a time they felt especially good or bad about their job. they also concluded that causing good feelings tended to differ from those associated with bad feelings. this discussion reveals the tension between ‘good’ (functional value) and ‘beauty’ (aesthetic value) in organizations. valuing ´good´ in organizations concerns a ‘standard’, probably related to business economic value or contribution to business goals. the lists of found oas exhibit largely similar characteristics to the various lists of 'good’ of ‘functional’ and modern organization characteristics like for example drucker ( ), maister ( ), mintzberg ( ), shapero ( ), and despres and hiltrop ( ) argued. and the empirical studies showed that oas positively (canonical) correlate with affective commitment which contributes to performance. thus, seemingly beauty is a kind of good or functional, like plato believed? and is an aesthetic judgment equal to a moral judgment? and is aesthetic value in organizations equal to functional value? or are they dependent of each other or just separated like kant’s distinction between free and dependent beauty? can aesthetic value contribute for example to economic value and to affective commitment? and can something in organizations be beautiful without being (a degree of) good? answering these questions seems to be delicate matter and difficult. literature study as well as the conducted empirical studies offer some first suggestions for criteria for distinguishing ‘good’ (functional value) from ‘beauty’ (aesthetic value). four topics were examined in literature which are: ) criteria for aesthetic judgments in arts; ) the distinction between aesthetic judgment and ethic or moral judgment made in the arts; ) the aspect of aesthetic supervenience and; ) the role of aesthetic value combined with other values in design disciplines like product design and architecture. in part of this dissertation, in paragraph . the criteria for functional beauty are described in detail. in the second empirical study the correlation of oas with ‘attention to beauty contributes to performance’ was examined (see appendix ). for example, the oas qualities and style of management and all oas accommodating formal properties (coherence) show much higher correlation with this outcome than the oas workplace and house style do. which means that these oas are valued as functional as well as beautiful. but still, some oas, for example interior, opportunities for development and autonomy, can be judged as beautiful (high aesthetic value) without being very or always functional (low functional value). considering these results of analysis, the first suggestion - nothing more - for criteria for distinguishing ‘good’ (functional value) from ‘beauty’ (aesthetic value) in organizations are proposed. aesthetic value in organizations: . is disinterested interest, in that respect: a) oas represent high aesthetic value without representing high functional value and contribute to organizational value as long as beauty (in oas) is not dysfunctional. b) it concerns employees’ (intrinsic) motivational needs like cognitive, social, and psychological needs; part | empirical studies . is based on a degree of presence or attribution of aesthetic properties, like formal properties (‘internal causality’ because of harmony, climax, balance), representational properties (history or values for identification), and / or expressive properties (color, sound etc.) . is cognitive, perceptual, emotional as well as transcendental. . claims ‘universal validity’ within the organization it concerns: the judgment is generally agreed by the major group of employees as well as similar aesthetically judged by people outside the organization (without any interest); . results in contemplative pleasure. this last criteria is often mentioned literally in literature on aesthetics (e.g. hospers, ; carroll, ; scruton, ). based on the empirical studies, in particular those in which the affect grid was used, this criteria could be better described in terms of positive emotions such as euphoric or elated, caused by a positive aesthetic judgment accompanied by a high emotional impact. in anticipation of the next paragraphs, collected oas all comply with the last four criteria. in particular the criterion of disinterested interest shows different position of oas. the assessment of oas to intrinsic motivators is described in paragraph . . nevertheless, these proposed criteria must be applied with some caution and can be considered as challenges for future research. role of personal characteristics by conducting a cluster analysis the aesthetic judgment of oas by respondents was related to their personal characteristics such as age and educational level. three types of personal characteristics show a significant strong deviation from the mean scores, which are women, with age of - , and - years company tenure. this group concerns respondents ( %). the aesthetic judgment of all oas of this group is significantly lower. interesting is whether these results are confirmed by studies on the effect of gender, age, and tenure on affective commitment and on job satisfaction. much research on commitment suggests that gender is not a determinant of affective commitment (e.g. hawkins, ). there is general support in the literature for the notion that there is a positive correlation between organizational commitment and organizational tenure (e.g. mathieu and zajac, ; meyer and allen, ). meyer and allen ( ) proclaimed that analyses of organizational tenure generally showed a mild curvilinear relationship. but middle tenure employees possessed less measured commitment than new or senior level (by age) employees. some research on gender differences in job satisfaction confirms that women show a lower job satisfaction than men because of other expectations and responsibilities to job characteristics, family responsibilities, and personal expectations (e.g. hodson, ; bedeian, ). in terms of aesthetics, possibly their (disinterested) interest, which is an antecedent of aesthetic experiences (e.g. beardsley, ; osborne, ), moves from work to home. in contrast, many studies have shown a relationship between age and job satisfaction, indicating that older workers are more satisfied with their jobs than younger workers (e.g. berns, ; nestor & leary, ). studies concerning the relationship between tenure and job satisfaction show varying outcomes (e.g. freeman, ). so, partly the deviant scores of women, with age - , and - years company tenure can be explained and needs to be further examined in future. organisations ambient to apply and to exploit organizational aesthetics should take account of this group of employees. part | empirical studies aesthetic process: the role of time and position the aesthetic process lead to an aesthetic judgment (a result of the evaluation of the cognitive mastering stage) and an aesthetic emotion (an emotional reaction which is a by-product of the processing stages) leder et al. ( ) claim. this process of ( ) explicit classification, influenced by domain specific expertise, declarative knowledge, interest and personal taste; ) implicit memory integration, influenced by previous experiences; ) perceptual analysis; ) cognitive mastering, influenced by domain specific expertise, declarative knowledge, interest and personal taste, and ) evaluation) in particular is applied to experiencing the arts, and specific for short-term observations. in this dissertation employees are daily and for long periods of time exposed to more or less the same stimuli. so, by leder et al. distinguished previous experiences seem to be relevant in an organizational context. the empirical studies have shown that the aspect of previous experiences with the same stimuli (repetition in time) as well as the position towards the perceived object affect the aesthetic judgment of the perceiver. during the studies the aesthetic judgment was examined at four time points: ) during the period of employment with an employer (including the distinction short and long in service), ) after weeks of registration of paes and naes, ) after - months after registration of paes and naes and ) after departure and return to the employer. analysis of the data from the second study shows that the appreciation of a number of oas decreases over time. employees in the period from zero to two years in service show the highest beauty appreciation. people who are a few years longer in service show a lower appreciation. this applies particularly to the cultural component of the esh-model like rituals and working atmosphere and aspects of staff like the style of management, the balance between organizational goals and personal goals, attitudes towards the environment, opportunities for development and the coherence of things in the organization. brickman et al. ( ) denote this as the "nostalgia effect": ‘after a short peak in happiness, people become accustomed to the new situation and are no more happy than they were before the improvement’. results of the fifth study show that respondents after - months mention other events than they registered before, but the mentioned type of events show strong similarity. the repeated attention of observed oas and narrowing the scope of the full range of oas can be explained by the mechanisms of familiarity, aesthetic induction and possibly also prototyping (e.g. mastandrea, bartoli and carrus, ; kunst-wilson and zajonc, ; leder et al., ). these mechanisms are explained at the beginning of this paragraph . . considering these thoughts, when organizations recognize the importance of aesthetic experiences of employees, they continuously should awaken and guard the attention and appreciation for oas, in particular for the cultural aspects such as rituals, work atmosphere and aspects of staff like style of management, the balance between organizational goals and personal goals, attitudes towards the environment, opportunities for development and the coherence of things in the organization. continuously employees should be remembered of the full range of oas they daily observe in order to prevent the psychological mechanisms of prototyping and familiarity. kaplan et al. ( ) later introduced the term of mystery, referring to an organization scene that promises the opportunity for employees to reveal new oas and to be continuously surprised by new aesthetic experiences. this aspect refers to the often mentioned aspect of complexity in art (e.g. beardsley, ; leyton, ; leder et al., ) by which observers are longer interested because of the offered great spread and depth of stimuli (pepper, ). second , the interviews with returning employees (the fourth study) show that by changing the frame of reference, the new employer, the employee is again aware of what he appreciated in his previous organization. respondents experienced paes in the organization they returned in support of management, culture, involvement / solidarity with colleagues, interior / exterior and work. the main reasons for returning to their former employer are style of management and colleagues. part | empirical studies these results show that the position of the observer influences their aesthetic judgment of work and organization. their position can be distinguished in one as an observer from outside an organization and one as an employee. a comparison can be made with the role of an observer distinguished by guillet the monthoux ( ). in his gadameriam kreis, art work is considered from two perspectives: the perspective of creation (authors and technicians) and the perspective of interpretation (audience and critique). the fourth study shows that after leaving an employer the employee becomes aware of the beauty of his former employer after being confronted with a new reference, the beauty and ugliness of the new employer. the employer reflects from a position of audience on his own and former position as creator. thus, both antecedents of aesthetic judgment, time and position, need to be attended in organizations for continuously stimulating employees’ aesthetic experiences. affective commitment an important aim of this dissertation was to examine whether organizational aesthetics contributes affective commitment. by conducting a canonical correlation analysis as part of the second empirical study (see . . ), it was proved that the set of oas strongly correlates with affective commitment, represented by the outcomes pride, work pleasure, and flow experiences. besides this outcome attention to these oas also contributes to aesthetic value, represented by the judgments ‘beautiful organization’, ‘beautiful work’, and ‘attention to aesthetics contributes to performance’. many studies demonstrate that affective commitment can be considered as a predictor of performance (e.g. meyer et al., ; meyer et al, ; allen et al., ; meyer smith, ; rhoades et al., ). so organizational aesthetics can also be considered as the promise to performance. in the next section general design interventions will be proposed for achieving affective commitment as well as for developing beautiful organizations. part | empirical studies . . adapted organizational aesthetics framework an adapted organizational aesthetics framework the proposed organizational aesthetics framework is based on the affective events theory (aet) of weiss and cropanzano ( ) and the design reasoning of roozenburg and eekels ( ). after ending the empirical studies, three important adoptions must be made. the second and also the fourth empirical study have shown that employees get used to organizational aesthetic stimuli which influence their future aesthetic process. little ( ) criticized aet because of her opinion that new emotion may actually predict behavior better than the original felt emotion, which is not part of the framework. second, the aet framework was not developed for measuring affective reactions and attitudes over time and the repetition of observing the same stimuli. based on the same observation, leder et al. ( ) in their aesthetic process included an arrow from ‘previous experiences’ to the beginning of the process (implicit memory integration: e.g. familiarity, prototypically). in order to address both shortcomings the box ‘aesthetic process’ is divided (first adaption) into the boxes ‘aesthetic process’ and aesthetic judgment. second, in accordance with the model of aesthetic experiences of leder et al. ( ), a two-way arrow connects these boxes which expresses the role of ‘previous experiences’ (second adaption) and the mutual influence of the aesthetic process and the aesthetic judgment. the last adoption concerns the two-way arrow between the boxes function and needs in the design causality. this adoption will be elucidated in paragraph . in particular in the section about organization’s functions. figure . adjusted organizational aesthetics framework object subject (observer) properties aesthetic formal, expressive and representational properties needs motivational needs positive emotions caused by aesthetic experiences values aesthetic value function offering employees positive aesthetic experiences form organization design - organizational aesthetic stimuli (oas) - conditions for having paes/naes in work events job / work design - oas work events - oas employee - gender - age - education - years of occupation - years in organization - religion - aesthetic awareness - aesthetic sensitivity aesthetic process affective commitment aesthetic judgment - ‘beautiful organization’ - ‘beautiful work’ (paes / naes) emotions previous experience part | empirical studies part | developing beautiful organizations developing beautiful organizations ‘design, don't engineer; discover, don't dictate; decipher, don't presuppose’ (pascale et al., ) in this chapter the second research question of this dissertation will be answered: what design principles (design protocol) can be used to develop, redesign, and sustain an organizational design for professional organizations that decrease negative aesthetic experiences (naes) and increases positive aesthetic experiences (paes) of professionals? this chapter starts with describing the context of design. the design causality for beautiful organizations is described in paragraph . . in paragraph . the design principles are elaborated. interventions, as part of design interventions, to develop, redesign, and sustain an organizational design for professional organizations are described in paragraph . . this chapter concludes with indications and contra-indications for developing beautiful organizations. respondents reflected on most of the proposed design interventions and some interventions were tested. this validation is described in chapter validation. . context of design this dissertation started with the ambition to develop a tested design protocol (a set of design principles) for embedding ´aesthetic reinforcing conditions´ in the organizational design and work processes. these ´aesthetic reinforcing conditions´ will decrease negative aesthetic experiences and increase positive aesthetic experiences, ultimately to contribute to affective commitment of employees to the organization. in terms of the components, fundamentals, and methods of designing as stipulated by roozenburg and eekels ( ) and romme and endenburg ( ) adding value, particularly aesthetic value, to the design of the organization will be translated into design principles and design interventions. the goal is to create situations (aesthetic arrangements), with a large probability of paes and a small probability of naes, causing experiences of working in a ‘beautiful organization’, which contribute to affective commitment.´ aesthetic reinforcing conditions´ will be expressed in design principles as part of cimo- configurations (denyer et al., ). the overall (meta) cimo-configuration (see figure . ) expresses the next construction: for applying organizational aesthetics, organizations that do not exploit the opportunities of organizational aesthetics (c) in which organizational aesthetic properties are adjusted (object-oriented interventions) and /or employee’s awareness and perceptions of organizational aesthetic properties are influenced (subject-oriented interventions) (i) cause increased attention to (organizational) aesthetics (m) which will increase aesthetic value to / and affective commitment of the employee (o). part | developing beautiful organizations figure . meta cimo-configuration organizational aesthetics design interventions are rooted in eight design principles. literature on aesthetics advocates that interventions are particularly useful if they address object characteristics (organization’s function, properties and form) or the subject (i.e., employees’ needs and values) (e.g., scruton, ; girod et al., ; reber et al., ) and preferably both. two objects of redesign or change following from above, one can divide design interventions in two groups: ) subject-oriented interventions (the employee) and ) and object-oriented interventions (the work and organization design) which are being observed and which cause aesthetic experiences. therefore the proposed organizational aesthetics model is divided into a subject part and object part. the literature study as well as the conducted empirical studies have shown that employees’ aesthetic appreciation increases by enhancing their aesthetic awareness. even without changing oas (stimuli in events and organization characteristics) they observe. these, and also the conditions for experiencing aesthetics like time, can be considered as the second parameter for experiencing aesthetics. organizations are mainly designed with functional requirements, like effectiveness and efficiency, in mind. this dissertation is based on the idea that it has merit to design and develop organizations on the basis of a combination of functional and aesthetic requirements, or expressed in terms of value, functional value combined with aesthetic value. this dissertation shows that employees perceive aesthetics in current and existing organization aspects and artifacts, such as autonomy, organization goals and interior, which endorses the proposition that aesthetic properties supervene on non-aesthetic properties (e.g. scruton, ; sibley, ). this means that every organization potentially offers stimuli that trigger aesthetic experiences. thus, organizations don’t need to be redesigned for experiencing aesthetic value. organizations – or more specifically, its employees - only will have to learn to recognize and address aesthetic value in their organization aspects and artifacts. by focusing on the presence and effect of aesthetic properties as part of stimuli (oas) which cause aesthetic experiences, employees could become more aware of their aesthetic experiences and their need of it. and by naturally and slowly revealing and improving aesthetic properties in present oas also aesthetic value in organization aspects could be increased. in types of organizational change this can be defined as adaption: ‘a type of change that can be accommodated within the current culture and occur incrementally’ (johnson et al., , p. ). this type of change also shows similarity with the well known development approach focusing on the awareness of beliefs, attitudes, values of employees (e.g. bennis, ; schein, ). but besides applying this adaption and development-approach it is conceivable that many organizations also will explore or embrace organizational aesthetics in case of redesign initiatives such as process redesign, changing work design, or alliances and mergers (e.g. hammer and champy, interventions in context organizations that do not exploit organizational aesthetics mechanism increased attention to (organizational) aesthetics outcome judgment ‘beautiful work & organization’ organization’s outcome affective commitment employees’ needs values properties form function part | developing beautiful organizations ; davenport et al. ;). these types of change could be defined as reconstruction and revolution in which major structural changes and/or major strategic as well as culture change is intended (johson et al., ) the first empirical study proved that critical moments in organizations are used as an opportunity for change and re-design. in that situation, for redesigning for example new processes, roles, and organization structures, related oas, in particular the aesthetic properties they contain, could be part of the redesign process. so, in general there are two basic scenarios for developing beautiful organizations: a. an organization development project that has ‘beautifying the organization’ as prime objective, because the organization insufficient addresses and exploits beliefs, attitudes, (aesthetic) values of employees; b. an organization redesign project that is initiated because of functional problems or opportunities, but in which the organization redesigning uses aesthetic requirements next to the usual functional ones. for this dissertation, only the situation of applying organizational aesthetics in existing and not redesigned organizations will be elaborated (scenario a). because it is likely that these organizations are a majority and are able and willing to start quickly with organizational aesthetics. it is quite unknown whether organizations in the process of redesign are also receptive for organizational aesthetics. . design causality chapter discusses the lower part of the proposed organizational aesthetics framework. the boxes ‘form’ and ‘events’ together contain the organizational aesthetic stimuli (oas) which trigger aesthetic experiences of employees. both boxes can be considered as part of the design causality and design fundamentals of roozenburg and eekels ( ), which is the upper part of the proposed organizational aesthetics framework. this design causality describes the relationships between form, properties, function, needs and values. following this causality for organizations, form (the organization) is a system that is made by people for its properties. because of its properties it can fulfil one or more functions. by fulfilling functions an organization satisfies needs, and this gives people (e.g. the employee) the possibility to realize one or more values. roozenburg and eekels argue that in general many design processes proceed in the opposite direction which is more open- ended: from (aesthetic) value to form. for developing beautiful organizations, any organization regardless of context, this abductive approach should just start from value without being prescriptive of form; reasoning back from values to statements on functions that are worth fulfilling forms the kernel of the design process (roozenburg and eekels, ; claesson, ). it can be reasoned that the lower part of the framework provides input, in particular by the obtained empirical data, for the upper part of the framework. in this paragraph the implications for the design of beautiful organizations is discussed by describing the individual boxes of the design causality of roozenburg and eekels, which are value, needs, function, and properties. values and needs of employees before reflecting on what and how organizational aesthetics can be expressed, the arguments (why) for applying an aesthetic perspective on organization design will be illustrated first. value and needs concern the subject part of the object-subject interaction, i.e., the organization and the employee. the design fundamentals of roozenburg and eekels ( ) claim that ‘form follows value’. in this dissertation we aspire to combine aesthetic value with functional value to improve employees’ organizational engagement (e.g., affective commitment), because we think like argued by guillén part | developing beautiful organizations ( ), gagliardi ( ), and witkin ( ), that aesthetic value (‘seeking beauty or harmony’) should be part of organizational design beyond theoretical, economic, political, social, and religious value (allport et al., ). aesthetic value is assigned to the object people perceive and based on the aesthetic judgment and the caused emotion of the observer (mothershill, ; santayana, ; beardsley, ; hekkert, ). literature on aesthetics is very unanimous in the effects of experiencing aesthetic value by describing the outcomes of aesthetic processes. experiencing aesthetics causes feeling of pleasure (e.g. mitias, ; mothershill, ; osborne, ; santayana, ), sensemaking (weick, ; rafaeli and vilnai-yavetz, ; scruton, ) and triggers positive emotions (e.g. ittelson, ; freedman, ). the conducted empirical studies of this dissertation proved that employees experience pride, work pleasure, and flow experiences due to positive aesthetic experiences (paes). and these three outcomes are important components of affective commitment which is a strong predictor of organizational outcomes like employee retention, absenteeism, intensions to quit the organizations, customer-oriented behavior and performance (meyer et al., ; allen et al., ; meyer smith, ; rhoades et al., ; shivangulula, ; rego et al., ). so, aesthetic value satisfies needs, for individual employees as well as for organization’s management. this can be considered as a motivational perspective on design, like zhang ( ) supports. this perspective explains human’s various needs, the relationship among needs and psychological well-being, and environmental factors and their impact on goal-oriented commitments. the purpose of (re)design then is to positively support employees’ motivational needs like emotional needs (emotion and affects). zhang’s proposed needs and related design principles strongly show relationship with oas in which employees experience aesthetic value which were found during the empirical studies. the overview (table . ) below expresses these relationships. needs design principles (based on zhang, ) translated to organizational aesthetics psychological: autonomy of the self ) support autonomy autonomy ) promote creation and representation of the identity of the self personal development opportunities goal and value congruence cognitive: competence and achievement ) design for optimal challenge offered challenges development opportunities variety of tasks goal achievement / task completion attention to craftsmanship goals of employees organization goals attention to new ideas working on same goals contribution to society products & services ) provide timely and positive feedback feedback of colleagues social and psychological: ) facilitate human-human interaction interaction (contacts) with colleagues, customers and management part | developing beautiful organizations needs design principles (based on zhang, ) translated to organizational aesthetics relatedness qualities of employees work attitude of employees composition of staff internal communication alignment management – employees business approach attitude towards environment contacts with environment ) represent human social bond collegiality internal cooperation work atmosphere organization rituals organization image organization mission social and psychological: power, leadership and followership ) facilitate one’s desire to influence others influence or control influence on planning ) facilitate one’s desire to be influenced by others feedback of colleagues qualities of management style of management support of management aesthetic: space and media ) induce positive emotions via physical stimuli house style interior / exterior workplace ) realize symmetry and order alignment of activities coherence of things table . relation motivational needs (zhang, ) and organizational aesthetics after this comparison of oas that contribute to needs, it can be determined that aesthetic needs in organizations represent in particular intrinsic motivations of employees or so called motivators (intrinsic to the work itself like achievement, recognition, and responsibility) suggested by herzberg and colleagues (herzberg et al., ). organization’s functions before discussing the transfer of the aesthetic perspective to an organization’s function, the function of a design will be explained in a broader perspective than only the function of organization design. the concept of function is important for thinking about how designers and users relate to artifacts (crilly, ). this is because designers work to produce descriptions of artifacts that will perform certain functions (roozenburg and eekels, ), and because users derive benefits from artifacts that have the capacity to perform those functions, or the capacity to perform other functions (crilly, ; chandrasekaran and josephson, ; rosenman and gero, ). in many design disciplines combinations of functions have been introduced such as a part | developing beautiful organizations combination of operative functions (e.g. transforming, controlling), structural functions (e.g. connecting, supporting) and usability functions (e.g. simplifying, exhorting) (warell, ), a combination of techno-, socio-, and ideo-functions (schiffer, ) and a combination of aesthetic and non-aesthetic functions (e.g. zangwill, ) like this dissertations is focused on. in literature described functions of ‘modern organizations’ such as responsive and self-organization (pascale et al. ), sensible and sense-making (hasan et al., ; guillet de monthouw, ), appreciative (avital et al., ), life affirming (whitney, ), and creating value (bryan and joyce, ; zandee, ) show relations with underlying needs and values of employees. organizations like other design disciplines consider a function of a design as user-centered and much more diverse. and something that is perhaps even more important from an aesthetic perspective is that function, as used in design fundamentals of roozenburg and eekels ( ), connects and interacts between the object (organizations) and subject (employee). this increasing relationship between design and user can be defined as a ‘relational paradigm’ (warell, ) referring to the concept of affordances: “what one system (say, an artifact) provides to another system (say, a user)” (warell, , p. ). for users, it is well known that they pursue a variety of goals (crilly, ) and that artifacts are valued for the roles they play in fulfilling those goals (csikszentmihalyi and rochberg-halton, ). so, for organizations adding aesthetic value to organizational design means that an added function of the organization is offering paes to employees in order to increase their aesthetic judgment and their affective commitment. and if organizations will accept and adopt the aesthetic lens, and thus admit the need for aesthetic experiences and value, organization features may exist independently of each other, their value for explaining organizational form and function comes from how they are enacted together (zammuto et al., , p. ). figure . function as connector of object (organization) and subject (employee) this more human-centered focus, most of the characteristics of mentioned ‘modern organizations’ can be strongly associated with a motivational perspective on design, like zhang ( ) supports. this perspective explains human’s various needs, the relationship among needs and psychological well-being, and environmental factors and their impact on goal-oriented commitments. as a human-made thing (the organization) ‘purposely is envisioned to fulfill human needs and to support human values. creation and design should then be guided by such understanding’ (zhang, , p. ). if organizations do so, they will embed the role of aesthetic value into their function with consequences for organization’ properties and form. in that situation, the organization is starting this design causality with aesthetic value. reflecting on this change of the organizational function the classical rules ‘form follows function’ (introduced by louis sullivan in ) and later ‘structure follows strategy’ (chandler, ) - which have been the basic motors for organization design, architecture, and product design for long - the applied design causality only concerns function, properties and form. by considering the approach of ‘form follows value’ (roozenburg and eekels, ) or ‘form follows meaning’ (schmid-isler, ) which undoubtedly expresses the extended function of ‘modern organizations’, a more human-centered focus allows the addition of needs and values of employees to the design object subject (observer) properties aesthetic formal, expressive and representational properties needs motivational needs for positive emotions caused by aesthetic experiences values aesthetic value function offer employees positive aesthetic experiences form organization design - organizational aesthetic stimuli (oas) - conditions for having paes/naes in work events job / work design - oas part | developing beautiful organizations causality. a two-headed arrow between function and needs was added because employees as well as potential employees will possibly assess organization’s function in terms of its attention to aesthetic value. and they will possibly continuously assess and consider whether their values and needs fit with those of the organization. in terms of a personal-organization fit (e.g. chatman, ), for employees (during bilats and performance reviews) as well as for potential employees (during job interviews) the organization continuously should show and monitor its value congruence and how this is embedded in organization’s function. below (table . ), the main characteristics of organizations with the aesthetic lens are compared with those more traditional organizations. non-aesthetic lens aesthetic lens technocratic cognition human resources shareholder needs reflection (systematic, on planned goals) non-aesthetic properties measure and checkout objectivity definitions, rules, and procedures distance (observer perspective) analytical evaluative human-centered & value based affective (evocative experiences) human emotions employee motivational needs reflexivity (‘being-in-the-world’) aesthetic properties support and inspire subjectivity (universal) illustrations commitment (player perspective) synergism interpretative table . characteristics organizations non-aesthetics lens versus aesthetic lens properties this dissertation in particular examined stimuli in work and organizations (oas) that trigger aesthetic experiences. this resulted in a list of oas. it should be emphasized that in literature on aesthetics generally is accepted that aesthetic experiences are triggered by objects because of the recognition and attribution of aesthetic properties (such as formal, representational, and expressive properties) as part of these objects (e.g. goldman, ; zangwill, ). so, following this reasoning, these collected oas are the carriers of aesthetic properties. these oas can be considered as objects in a specific context (different organizations) which trigger employees’ aesthetic experiences. because these oas are context-related, for example oas mentioned by surgeons in the fifth empirical study differ from oas mentioned by teachers, it is more interesting to examine the generic aesthetic properties these oas conceal. because following roozenburg and eekels ( ) design fundamentals, beautifying organizations means to be more conscious and to improve organization’s aesthetic properties. thus, an organization is perceived as beautiful by someone because of his or her recognition or attribution of aesthetic properties carried by some oas. the literature on aesthetics argues that people have aesthetic experiences because of the recognition or attribution of aesthetic properties in these stimuli and distinguishes different types of aesthetic properties. based on the literature, a tripartite division was proposed of formal properties, expressive / sensory properties, and representational ´properties (goldman, ; wagner ( ). expressive properties (color, sound, etc.) for attraction, representational properties (symbolic value, history, values, etc.) for identification, and formal properties (harmony, balance, tension, etc.) for structuring. part | developing beautiful organizations formal properties kant’s work (veenbaas and visser, ) stands at the cradle of the formalism, by noting the aspect of beauty of ‘internal causality’, ‘internal efficiency,’ and ‘internal complexity’, mainly referring to nature by mentioning characteristics such as regularity and symmetry. formalists, later endorsed by bell ( ) and fry ( ), claim to not mind the content, the sensory elements of the painting is built - line, color, space, light and shadow - but the formal relationship between these elements, the form of the whole, ultimately determines significant form (van den braembussche, ; stecker, ). these formal properties concern aspects such as harmony, balance, repetition, climax, and grouping or the gestalt properties like simplicity, predictability, and motif. many designers of different design disciplines like dance, product design, and architecture recognize the important role of formal properties as part of design. wagner ( ) even speaks about ‘the principles of design’. the presence of formal properties in organization design is sporadically suggested in literature (dean, ; white, ; gerstein, ; rindova et al., ) or is expressed in the approach of organization as a whole (gestalt) (rindova et al, ; peng, wen-shien, ) and needs to be confirmed and further concretized. the previously used esh-model actually refers, without mentioning this earlier, to the organizational aesthetic stimuli (oas) ‘coherence of things’. e (evenwicht) means balance, s (samenhang) means coherence and h (heterogeniteit) means heterogeneity. the selected oas, such as alignment of management and employees, balance of organization goals and goals of employees, alignment of activities and working on the same goals, can be considered as formal aesthetic properties like harmony and balance. all six formal properties show strong (canonical) correlation with the set ‘aesthetic value’ (. to . ) and with the set ‘affective commitment’ (. to . ). when categorizing these six oas according to leyton and ramachandran ( ) eight laws for evaluating artwork (peak shift / climax, isolation (simplicity, ‘less is more’), grouping, contrast, perceptual problem solving, symmetry, abhorrence of coincidence / generic viewpoint, repetition, rhythm and orderliness, balance and metaphor), balance and symmetry seems to be most represented by these six oas. thus, formal properties discussed in the arts disciplines and other design disciplines such as product design and architecture, also seem to play a major role with relation to aesthetic experiences in organization design. based on numerous formal properties mentioned in organization science literature (see appendix ) and the formal properties discovered in the fourth empirical study (see appendix ), it is assumable that those six formal properties as part of the used survey are important but not encompassing. further research needs to be done to complete this list of formal properties in organizations. representational properties in the theory on aesthetics identification is linked with the representation of the work of art (cooper et al., : zangwill, ; parker, ; scruton, ; mitias, ; rafaeli and vilnai- yavetz, ). representational properties concern ‘phenomena mediated by interest’ (zemach, ), and fulfill a role of proximity, recognition and identification for the observer (lafierre, ). veryzer et al. ( ) examined later the influence of unity and prototypically on aesthetic responses to product design and builds on the theory of the gestalt-theory which stated that ‘beauty is dependent on the degree to which an object displays relations consistent with the gestalt laws of organizations like ‘good continuation’ and ‘good shape’ realized by aspects like unity’. prototypically can be used as a concrete design principle, according to veryzer et al., namely, ‘common designs already existing in the marketplace can be systematically altered to make them less typical. and second, the use of prototypically refers to the subjective perceptions of typically or category representativeness’. part | developing beautiful organizations this mechanism is identified by zhang (zhang, ) concerning the need for attachment, connectness, and belonging to a group (social and psychological needs). the perceiver has aesthetic experiences because of the attribution of aesthetic properties in the object or artifact, which is advocated by the subjectivist view on aesthetics (e.g. beauty is ‘a function of idiosyncratic qualities of the perceiver and all efforts to identify the laws of beauty are futile’ (reber et al., , p. ). employees’ qualities and work attitude - expressed in events like acts of colleagues and acts of management - as well as organization mission and goals (like to contribute to society) concern representational ´properties´ and the importance of value congruence for a good person– organization fit and affective commitment and identification (tan and akhtar, ; rahman and hanafiah, ; carmeli, ; herrbach, ; o'reilly and chatman, ; friedson, ; parry, ; meyer and allen, ). both rokeach’s (rokeach, ) very often used list of ‘terminal’ and ‘instrumental’ values as well as schwartz’s value domains (schwartz, ) exhibit strong relationship with some of the registered oas. the overview below (table . ) shows relationships between values identified in literature and oas found in the conducted empirical studies which include largely representational properties. organizational aesthetic stimuli (oas) personal values (rokeach, ; schwartz, ) autonomy internal cooperation, collegiality and ‘receiving appreciation and recognition’ (event) offered challenges and ‘coming to an insight, learning and being positively surprised’ (event) variety of work goal achievement and work on the same goals development opportunities freedom and independence friendship, helpful, loyal and sense of belonging stimulating life a varied life feeling of achievement, ambitious and successful intellectual and competent table . overview relationship organizational aesthetic stimuli (oas) with personal values the importance of values in aesthetic experience in organizations is exhibited by a strong (canonical) correlation of employee’s work ethics, internal cooperation, offered challenges, internal communication and products and services, development opportunities, and organization goals. also organization culture (work atmosphere) could be considered as part of representational properties, following many definitions of culture, like realin´s: ‘culture basically values autonomy, expertise, sense of ethics, meaningful and challenging work, and dedication to service delivery’ (cited by vandenberghe, , p. ). because of the strong relationship of these oas with values, it may be concluded that these oas are of great importance to the role of identification of employees with the organization. for increasing paes triggered by this type of property, organizations should monitor and strengthen their representativeness and legibility of mentioned oas (veryzer et al., ; kaplan et al., ; wasseman and frenkel, ). expressive properties finally, expressive properties concern secondary qualities or so called sensory properties (color, sounds, tastes, smells) (zangwill, ), ‘aspect’, evocative or affective and qualities of the object (like dignified, solemn, sedate, pompous , charming, joyful ( osborne, ) and taste qualities (‘garish’, ‘beautiful’) (hermeren, ). this type of property is most related to the personal taste part | developing beautiful organizations and style of the observer (e.g. reber et al., ; cooper et al., ) and can be recognized in oas like house style, interior, and exterior. in general, these oas do not strongly (canonical) correlate with the set ‘aesthetic value’ and with the set ‘affective commitment’. the overview below (table . ) shows examples of aesthetic properties expressed. notable is that the mentioned expressive / sensory properties show relatively lower (canonical) correlations with aesthetic value and with affective commitment. value congruence is added in this overview because of the relevance for the person–organization fit. aesthetic properties system aesthetics (organization design) process aesthetics (job / work design) result aesthetics formal properties (for structuring) coherence of things alignment management and employees alignment organization goals and individual goals (goal congruence, p-o fit) alignment of activities working on same goals (collective ambition) composition of employees cooperation (internal) value congruence (p-o fit) goal progress goal achievement representational ´properties´ (for identification) organization mission and goals (e.g. contribution to environment) work atmosphere (culture) employees’ qualities, work attitude and goals image business approach / organization philosophy style of management attention to new ideas attention to craftsmanship rituals like ceremonies, language, manners and jokes development opportunities autonomy variety of work offered challenges interaction with colleagues / internal cooperation involvement and solidarity colleagues interaction with customers attitude towards and contacts with environment receive recognition and appreciation products and services image expressive / sensory properties (for attention) house style interior / exterior workplace -- -- part | developing beautiful organizations aesthetic properties system aesthetics (organization design) process aesthetics (job / work design) result aesthetics qualities and style of management residue -- internal communication influence of staff -- table . oas categorized according to aesthetic properties so, it can be concluded that this type of aesthetic property does not strongly contribute to outcomes of organizational aesthetics. organizations that want to apply the aesthetic lens or aspire to improve affective commitment of their employees should better pay attention to oas which contain formal and representational properties. spaces of understanding, relatedness, and exploration this division of oas on the type of aesthetic properties provides an initial role of aesthetic properties in the perception of aesthetic value in oas. and the overview shows that aesthetic properties distinguished in oas show strong similarities with those distinguished in objects and stimuli in other design disciplines in which the role of aesthetics in irrefutably accepted, supported, and exploited. the three used types of aesthetic properties concern categories which include various individual aspects. for example, leyton and ramachandran ( ) identify eleven formal properties which are peak shift (climax), isolation, grouping, contrast, perceptual problem solving, symmetry, abhorrence of coincidence (generic viewpoint), repetition, rhythm (orderliness), balance and metaphor. examples of representational properties are elegance, gracefulness, prettiness (osborne, ), and provocative, flowery, terse, vulgar, stylish, rude, polite, candid, arty, romantic (zemach, ). examples of expressive properties are dignified, solemn, sedate, and pompous (osborne, ) and color, sounds, tastes, and smells (zangwill, ). an example of a specific selection of aesthetic properties that trigger aesthetic experiences is the environmental preferences model of kaplan et al. ( ). this model postulates that people will have two basic needs in environments: to understand and to explore. kaplan et al. proposed specific properties used for the informational variables, which are coherence (immediate understanding), complexity (immediate exploration), legibility (inferred understanding), and mystery (inferred exploration). for having and inducing paes, also in organizations, it is important to determine which specific aesthetic properties - accommodated by oas - trigger aesthetic experiences. after reflecting on the specific aspects of aesthetic properties the categorized oas accommodate, more specific aesthetic properties of organizations can be determined. formal properties are represented by oas such as coherence of things, alignment of activities or alignment of personal goals with organization goals in particular concerning balance and symmetry. these oas are of examples formal properties and they all show a very strong (canonical) correlation (>. ) with aesthetic value. peak shift (climax) also can be distinguished as an important formal property which is more work related. goal achievement / task completion were most mentioned oas in the fifth empirical study. those identified specific formal properties are labeled part | developing beautiful organizations with the names ‘coherence’ and ‘accomplishment’. representational properties incorporated by very often mentioned oas such as autonomy, organization goals and employee’s work attitude are much more difficult to specify. but they all seem to concern employees’ and organizational values (zhang, ). value congruence and goal congruence are important determinants of a good person–organization fit, affective commitment and identification (e.g. rahman and hanafiah, ; carmeli, ; herrbach, ). this group of oas accommodating representational properties can be divided into oas concerning organizational identity (e.g. products & services, organization mission and goals, and rituals in particular representing organization strategy and culture) and oas concerning work identity (e.g. autonomy, feedback, and development opportunities). because respondents do not distinguish these two types of identities from each other (see results of canonical correlations in second study) these groups of oas are labeled by one specific property which is ‘recognition’. expressive properties are accommodated by oas like house style, interior, exterior and workplace, concern in particular color and style. they must be recognized by management but these oas show low (canonical) correlations with aesthetic value as well with affective commitment. they do not seem to contain much aesthetic value in relation to other oas in the organization. therefore they are not labeled as an important aesthetic property of beautiful organizations. these four aesthetic properties are supplemented with one property. literature as well as the empirical studies express the importance of keeping employees intentionally conscious of their aesthetic attitude (e.g. steinkraus, ; cupchik and laszlo, ; osborne, ; zemach, ;), enable them to continuously discover and desire novelty and opportunity (barrett and cooperrider, ) and avoid the psychological mechanisms of familiarity and prototyping (e.g. mastandrea, bartoli and carrus, ; kunst-wilson and zajonc, ; leder et al., ). therefore ‘mystery’ is supplemented referring to an organization scene that promises the opportunity for employees to desire, descry and reveal new oas and to be continuously surprised by new aesthetic experiences (kaplan et al., ). this property can be considered as a third formal property of beautiful organizations because of its strong resemblance with ´perceptual problem solving´ (leyton and ramachandran, ), and ´complexity´ (e.g. leyton, ; beardsley, ; leder et al., ). part | developing beautiful organizations in figure . aesthetic properties of beautiful organizations are expressed. figure . classification of aesthetic properties of beautiful organization not only the selected properties are interesting but also the needs kaplan and colleagues distinguish. understanding and exploration can be considered as mechanisms or triggers which cause aesthetic experiences (e.g. girod et al., ; leder et al., ; steinkraus, ; cupchik and laszlo, ; osborne, ; zemach, ). it is very likely that employees are having paes because they understand that organizational aspects such as activities and goals show coherence. so, at best, an organizational design is ‘self-explanatory’ and legible (e.g. frey et al., ; kaplan et al., . second, it is very likely that employees are having paes because they can accomplish and explore things and goals in their organization, in short and medium term (accomplishment) and in future (mystery). third, the mechanism of relatedness can be distinguished. this mechanism was not identified by kaplan and colleagues. probably because their model for preferences concerns needs in environments in which the mechanism of identification or representativeness is less relevant. distinctive from the arts and applied arts, organizations can be considered as living and dynamic systems, in particular because they are formed by social constructs of people (see differences in table . ). regarding to this issue, and referring to the comparison of oas to zhang’s ( ) motivational needs where a design should cater for, employees will also have social and psychological needs. the empirical data clearly showed that employees also experience aesthetic value in oas because of their recognition and attribution of representational properties, in particular in recognition and collaboration. so, understanding, relatedness and exploration can be considered as important mechanisms for experiencing aesthetic value in organizations due to the recognition and attribution of aesthetic type of aesthetic property specific property examples of oas coherence represen- tational properties expressive properties accomplishment formal properties collaboration recognition coherence of things alignment of activities balance between organization goals and employee’s goals work together on same goals goal progress goal achievement / task completion personal development interaction with colleagues & customers internal cooperation working on the same goals organization mission organization goals products & services autonomy work attitude employees house style interior / exterior color / style offered challenges work variety opportunity for employees to descry and reveal new oas mystery part | developing beautiful organizations properties in oas. these characteristics of organizational environments are very much in line with the approach of organizational spaces (e.g. lefebvre, ; watkins, ; taylor and spicer, ; beyes and steyart, ). this approach was developed in particular for shaping emotions, attitudes, behavior, human experiences, of employee’s sensemaking, imagination and feeling of the people who use a given space (wasserman and frenkel, ). the spaces of understanding, relatedness and exploration are ‘directly lived through associated images and symbols, and hence the space of ‘inhabitants’ and ‘users’’ (lefebvre, , p. ). advancing abstract organizational (aesthetic) spaces will likely stimulate applying abductive reasoning, because organizations will be challenged to shape and refine understanding, relatedness and exploration (dorst, ). for creating and facilitating these three aesthetic spaces, in particular for inducing paes, coherence, accomplishment, recognition, collaboration, and mystery are translated into design principles which are described in the next section. by identifying the main specific aesthetic properties and spaces in organizations can be wondered whether the aesthetic process model of leder and colleagues (leder et al., ) (see figure . . in part and in part ) sufficiently discusses these features. aspects of coherence are clearly recognized in the process of perceptual analysis. accomplishment shows some similarity with the aspects of peak-shifts as part of process of implicit memory integration. collaboration and recognition can be related to aspects of cognitive mastering. and finally mystery can be related to previous aesthetic experiences, in the sense that organizations anticipate the habituation to stimuli that previously caused aesthetic experiences. so, the process model of leder and his colleagues primarily seems to be appropriate to be applied to organizational aesthetics. a more specific aesthetic process model related to work and organizations could be developed for future research in which the spaces of understanding, relatedness and exploration as well as the five specific aesthetic properties of beautiful organizations are better illuminated. part | developing beautiful organizations . design principles design principles in order to make the transition from the idea of organizational aesthetics to a design (the development of beautiful organizations), design principles are developed and elaborated into design interventions, inspired by the design logic of romme and endenburg (romme and endenburg, ). they suggest a science-based approach to organization design which includes five components of organization science: construction or design principles, propositions or design rules, organization design and implementation, and experimentation. a design principle basically describes the logic of intervention-outcome: ‘to achieve a, do b´, while design rules are ‘elaborate solution-oriented guidelines for the design process’ (romme and endenburg, , p. ). in this dissertation design principles are expressed in cimo-configurations (denyer et al. ). for organizational aesthetics the following meta-cimo was developed (see figure . ): context intervention mechanism outcome an organization that does not exploit the opportunities of organizational aesthetics (c) adjusting organizational aesthetic properties (object-oriented interventions) and /or influencing employee’s awareness and perceptions of organizational aesthetic properties (subject-oriented interventions) (i) increased attention to (organizational) aesthetics (m) increased aesthetic value to and affective commitment of the employee (o). table . overview of components of meta-cimo organizational aesthetics in relation to design principles this can be simplified to the next configuration: ‘if you want to achieve a (outcome o) in context c, then do b (intervention i)’ (denyer et al. ( ). one of the aims of this dissertation is to understand how managers can increase the affective commitment of employees through managing positive and negative aesthetic experiences. basically, to manage the aesthetic experiences of the observer (employee), the organization should offer organizational aesthetic stimuli (oas, see the list of collected oas in table . and in table . ) that positively affect positive aesthetic experiences (paes) and negatively affect negative aesthetic experiences (naes). and being consequent with the design fundamentals of roozenburg and eekels ( ), form, properties, and function (object: organization design) need to change when addressing and stimulating (positive) aesthetic needs of employees and their attention to aesthetic values (subject). here, the in aesthetic literature strongly advocated distinction between object and subject becomes visible. the mentioned design logic ‘starts’ with adding the idea of aesthetic value. from this action, thus the design logic is ‘moving’ and for experiencing aesthetic value basically two overarching design principles can be distinguished. ) address and stimulate employees’ need for positive aesthetic experiences by increasing their awareness of organizational beauty (subject); ) increase aesthetic value in organization’s function, properties, and form (object). part | developing beautiful organizations these two design principles express roozenburg’s and eekels’ ( ) design fundamentals. following these fundamentals, addressing and stimulating employees’ need for (positive) aesthetic experiences by increasing their attention to aesthetic value (subject) will fulfill their latent motivational needs (design principle ). following this ambition, the function of the organization will be complemented with offering employees aesthetic experiences (paes) caused by perceived aesthetic value in oas (design principle a). to realize this added function, organizations should increase the aesthetic value of oas by assessing and rearranging its aesthetic properties (design principle b). these two overarching design principles, summarized in roozenburg’s and eekels’ ( ) design fundamentals actually only define the objects of change and (re)design. for applying these design principles in terms of ‘if you want to achieve a (outcome o) in context c, then do b (intervention i)’, eight design principles are elaborated as part of single cimo-configurations for which the following reasoning has been used. for embedding value to the object (the organization) the subjects (the employees and management) must be conscious of this value and of their need for giving attention to organizational aesthetics (design principle ). if this state of mind and awareness is achieved, and the need for aesthetic experiences is salient, a reason, or critical moment must be determined to start with focusing or adding aesthetic value to the organization (design principle ). only participants working within the intimacy of the organization can determine what they consider as beautiful and ugly in their organization. as such, they are important in determining what needs to be beautified. therefore, managers must arrange collaborative change methods or design methods by which as many participants from the organization contribute (design principle ). in this process of analysis, change, and redesign, the fifth empirical study indicated that managers must be aware that emotions caused by negative aesthetic experiences (naes) are long lasting and have more emotional impact than positive aesthetic experiences (paes) (e.g. baumeister et al., ). so organizations should induce paes (design principle )and should avoid naes (design principle ). if organizations recognize the value of aesthetics and the need of employees for having positive aesthetic experiences, they should consider how to embed and secure the aesthetic perspective in daily organization routines, to make it visible, negotiable, and amendable (design principle ). in addition, if they consider applying the aesthetic perspective, they must remember that employees get used to the stimuli which causes paes and naes which was proved by empirical data. organizations continuously should arouse employees’ aesthetic awareness by keep them sensitive for aesthetic value surrounding them and by offering new discoveries which affect aesthetic experiences (design principle ). these eight design principles are identified as part of single cimo- configuration (see table . ). part | developing beautiful organizations c c (specific) i m o (specific) o o rg a n iz a ti o n s w h ic h d o n o t e xp lo it o rg a n iz a ti o n a l a e st h e ti cs lack of awareness of aesthetic value . enhance aesthetic awareness and sensitivity (priming and reframing) motivation change willingness freedom ju d g m e n t ‘b e a u ti fu l o rg a n iz a ti o n ’ & a ff e ct iv e c o m m it m e n t lack of critical moments and occasions for attention to organizational aesthetics . utilize critical moments and occasions for attention to aesthetics commitment focus occasion readiness lack of ‘channels’ for applying organizational aesthetics . apply collaborative and reflexive change methods or design methods commitment interaction influence empowerment cooperation ownership less positive emotions caused by aesthetic experiences . induce paes relatedness understanding challenge increased chance of judgment ‘beautiful organization’ many negative emotions caused by aesthetic experiences . avoid naes avoidance reduced risk of resentment less continuous attention and securing of attention to organizational aesthetics . incorporate the attention to aesthetics in organization routines stability trust coordination transparency increased chance of judgment ‘beautiful organization’ less continuous attention and securing of attention to organizational aesthetics . guard mystery: retain and increase aesthetic awareness and sensitivity imagination desire discovery challenge ambiguity surprise learning stable judgment ‘beautiful organization’ chance of a bad p-o fit, based on aesthetic value . increase the chance of a good p-o fit, based on aesthetic value recognition affinity solidarity trust increased chance of judgment ‘beautiful organization’ table . overview cimos for organizational aesthetics for the meta-cimo configuration for beautiful organizations, the mechanism ‘increased attention to (organizational) aesthetics’ was defined (see figure . ). this mechanism covers all mentioned single interventions, and is regarded as key mechanism identified in the literature (cf. denyer et al., ). mechanisms and outcomes in order to select design interventions for composing beautiful organizations, the cimo- configurations not only help to express relationships between the four components, but also force the researcher to select interventions that really effectuate a certain mechanism and outcome. figure . shows a sort of meta cimo-configuration for organizational aesthetics. based on previous considerations, eight design principles, which are considered as interventions for developing beautiful organizations, can be expressed in underlying cimo-configurations (cimos). these can be considered as established configurations as part of the meta cimo-configuration shown in figure . .these cimos are operationalized in the paragraph . . the mechanisms are those which will be effectuated by the interventions in the specific context, causing a specific part | developing beautiful organizations outcome. those mentioned outcomes are effects that contribute to a higher affective commitment to the organization of employees. these eight principles are placed in a specific order. they are positioned according to the phases of awareness, fit, development and change, securing, and perpetuation of aesthetics in organizations (see table . ). these phases are elaborated from the development-approach and the chosen scenario of an organization development project that has beautifying the organization as prime objective (see section . ). the mentioned first seven principles cover the process, the content of change as well as the focus on subject (employee) or object (organization) or both. phases object-oriented design principles (organization) subject-oriented design principles (employees & management) a. awareness -- . enhance employees’ aesthetic awareness (priming and reframing) b. fit . utilize critical moments and occasions for attention to aesthetics -- c. design & change . induce paes . avoid naes . apply collaborative and reflexive change methods or design methods d. securing . incorporate the attention to aesthetics in organization routines . incorporate the attention to aesthetics in employee behavior e. perpetuation . guard mystery: continuously offer employees possibilities to discover new stimuli which effect new aesthetic experiences. . guard mystery: avoid the habituation of beauty and ugliness of employees by occasionally enhancing their aesthetic awareness table . relationship phases of development and design principles the eighth design principles concern a situation outside this process of development, because it could be applied for any organization in any situation. in the following paragraphs the design principles are elaborated. in paragraph . individual design interventions for each design principle are described. . enhance employees’ aesthetic awareness this dissertation begins with the observation that currently most organizations are being designed and controlled based on the scientific management paradigm (e.g. taylor, ; morgan, ; mintzberg, ; kets de vries, ). the true and the good dominate in this perspective. the beautiful, the attention to aesthetics, is a perspective or frame for which up till now has been scant attention in organizations (allport et al., ; guillén, ; strati, ; gagliardi, ; taylor and hansen, ). for revealing and exploiting aesthetic value, the aesthetic consciousness, the preparations, and sensitivity of the perceiver and employees’ state of aesthetic attitude need to be attended first (steinkraus, ; cupchik and laszlo, ; osborne, ; zemach, ; mitias, ; dziemidok, ; ginsberg, ). they are crucial for experiencing aesthetics (pepper, ; fairchild, ; mitias, ; leder et al., ). employees must become more aware of their ‘enactment’: ‘the interaction with the context and from the interaction with the context cues are selected retrospectively as part of making sense of the interaction’ (lyhne, , p. ). this can be considered as priming or even reframing. priming is the phenomenon whereby a recent experience activates the memory and behavior and unconsciously influences this behavior (e.g. part | developing beautiful organizations tulving et al., ; kolb and whishaw, ). according to shalev and bargh ( ), ‘priming- based interventions are based on the perception that relevant stimuli (primes) automatically activate a goal representation’, like enhancing aesthetic attention. the challenge for organizations is thus to achieve the activation of contextual cues (oas). this can be achieved by perceptual, semantic, or conceptual stimulus repetition, like is done during the empirical study by using the bel-book. reframing is the effort to change the dominant thought (frame) and action (bryan et al. ; bolman and deal, ; smith en huntsman, ). framing is the process of forming perspectives: the way in which someone describes and evaluates his situation (lindenberg, ). about change, sennett ( ) speaks about formatting as the first step of change in professional organizations. frames are abstract and are to be regarded as a box within which patterns reveal itself (sennett, ). they are mostly unconsciously, often very dominant and greatly determine our thinking and acting (lindenberg, ). accepting the aesthetic perspective on work and organizations is vital before any attempt to organizational change (pettigrew, ). by learning management and employees to recognize and adopt an affordance-based approach on organization design, particularly focused on aesthetic value, the first condition for having aesthetic experiences can be realized. secondly, the results of the empirical research have shown that employees get used to beauty and ugliness in their organization. it should be prevented that employees habituate to beauty and ugliness in their organization. this can be achieved by repeatedly stimulating and enhancing employees’ aesthetic awareness and sensitivity (priming and reframing) which is the first defined design principle for organizational aesthetics. employees should be continuously reminded the full range of oas they daily observe and positively appreciated earlier in order to prevent the psychological mechanisms of prototyping and familiarity (e.g. mastandrea, bartoli and carrus, ; leder et al., ). the use of the bel-book in the third empirical study has proved to be an effective instrument for priming respondents. respondents became more conscious of aesthetic stimuli in their environment. variation and confrontation with other perspectives (frames) and interpretations can stimulate reflection on fixations, dilemmas, and conflicts (bolman and deal, ). the exchange and confrontation of perspectives must ensure that managers and employees develop insights regarding mutual agreements and differences. it creates a collective (aesthetic) awareness, whereby employees become more consciousness of their needs for having aesthetic experiences, even in their work. in terms of aesthetics, variation of perspective to the perspective of interpretation (audience and critique), employees could reflect (confrontation) on notation and executions of the own organization by others (guillet the monthoux, ). thus, interventions are needed to address and to increase their aesthetic consciousness, the preparations and sensitivity and their certain state to have aesthetic experiences. interventions by which employees become more consciousness of their enactment: the interaction with the context and from the interaction with the context, oas are selected retrospectively as part of making sense of the interaction (weick, ). . utilize critical moments and occasions for attention to aesthetics the empirical studies have shown that aesthetic experiences are perceived in a large variety of oas across all components of the esh-model and also across system aesthetics, process aesthetics, and result aesthetics. so, for applying an aesthetic perspective to the organization, the organization needs to choose points of application and/or utilize a critical moment for addressing interventions for organizational aesthetics (e.g. kotter, ). the first empirical study suggests critical moments like rehousing /rebuilding, new management, and change to a more a value driven strategy. for example, when we apply the esh-model, organizations could start using the aesthetic perspective part | developing beautiful organizations to the oas related to staff or to strategy, such as work attitude of employees (staff) or products and services (strategy). the classification of oas along these six components can be used to prioritize occasions (such as new management or new products and services) and approaches (such as a culture-approach or staff-approach) for applying organizational aesthetics (see appendix and ). . apply collaborative and reflexive change methods or design methods the literature on aesthetics as well as the conducted empirical studies advocate that experiencing beauty is a personal activity (e.g. reber et al., ). although many aesthetic judgments are universal, they are still personal and subjective. thus, when starting applying the aesthetics perspective to the organization, it is important that all employees are involved in determining which oas or which aesthetic properties (such as coherence or accomplishment), and how these will be ‘embellished. for example bos ( ) recommends developing a reflexive interactive design approach by applying identification and connection of needs and values of stakeholders by providing adequate structure and certainty to the parties to actively participate, not only in the thinking process, but also in doing. this organizational development process is a dynamic process of mutual creation, in which acting will be continuously alternated with reflection (bos, ). secondly, reflexive change methods or design methods are recommended (e.g. avital et al.; ; whitney, ; barrett and cooperrider, ; zandee, ).these methods, based on design thinking, are often used in design disciplines in which aesthetic value naturally is addressed as part of the design such as architecture of product design. these methods, characterized by abductive reasoning, are slowly applied in organizations for redesign and change initiatives (barry and rerup, ; boland and collopy, ; hanson, ). . induce paes the several empirical studies proved that positive aesthetic experiences (paes) are triggered by several aesthetic stimuli (oas). in section . these oas are categorized in accordance with three types of aesthetic properties that trigger aesthetic experiences (see table . ). of these categories of properties more specific properties were indentified concerning the specific feature of each oas (see table . ). these specific properties are coherence, collaboration, recognition, accomplishment, and mystery. these principles could be applied to system aesthetics, process aesthetics, and result aesthetics (see table . ). some oas can be positioned in more than one cell. part | developing beautiful organizations system aesthetics process aesthetics result aesthetics s p a ce o f u n d e rs ta n d in g coherence coherence of things alignment of management and employees alignment of individual goals and organization goals composition of employees alignment of activities internal cooperation communication (internal) work together on same goals -- s p a ce o f r e la te d n e ss recognition employees’ work attitude and qualities qualities of management style of management attitude towards environment attention to craftsmanship organization philosophy / business approach offered challenges development opportunities organization mission organization goals & individual goals work atmosphere organization rituals internal communication autonomy image products and services collaboration employees’ work attitude and qualities interaction with colleagues and customers internal cooperation working on the same goals s p a ce o f e xp lo ra ti o n accomplish- ment organization goals development opportunities goal progress goal achievement / task completion learning results mystery qualities of management style of management offered challenges attention to new ideas exploration of stimuli in general related to system aesthetics exploration of stimuli in general related to process aesthetics exploration of stimuli in general related to result aesthetics table . oas categorized according to aesthetic properties of organizations part | developing beautiful organizations the oas house style, workplace, interior were not assigned to these five properties. they do not fit with one of these five properties because they accommodate expressive properties. this group of oas contributes least strongly to aesthetic value as well as to affective commitment. beautifying organizations means, following the design fundamentals of roozenburg and eekels ( ), being more conscious and improving mentioned organization’s aesthetic properties. thus, for inducing paes five aesthetic properties need to be more recognized or developed: a) reinforce coherence, achieved by a degree of aesthetic formal properties such as balance, unity in variety, and harmony; b) enhance possibilities for identification with the organization (recognition, which cause value and goal congruence), achieved by a degree of (attributed) aesthetic representational properties; c) condition accomplishment by stimulating goal achievement and task completion as well as the process for realizing these (goal progress); d) enable collaboration; and e) guard mystery. this aspect is been described below as a single principle. . avoid naes after reframing employees and management to a more aesthetic perspective, organizations can start beautifying their organization by revealing and enhancing their most important oas. much research has demonstrated the negative impact of negative emotions, like naes, on other positive and negative emotions. baumeister et al. ( , p. ) argue that ‘bad events had longer lasting effects. and bad events seem to produce stronger reactions than good ones.’ they claim there is an assortment of evidence that negative affect is stronger and more important than positive affect. they also suggest that ‘people try harder to avoid and escape bad moods than to induce or prolong good moods, and they remember bad moods and emotions better’(baumeister et al., , p. ). thus, for avoiding naes, those oas which cause these naes must be weakened or eliminated. this mainly concerns aspects which are dysfunctional and which are barriers for accomplishment. considering the collected naes in this dissertation, they will probably concern influence or control, goal achievement and goal progress (probably due to acts of management (basch and fisher, ), and acts of or interaction with customers and colleagues. initially, in the order of design principles ‘avoid naes’ was placed before ‘induce paes’ because of the longer and stronger impact of negative emotions. but because of the dominant choices of respondents for paes during the validation workshops and their strong preference for changing and redesigning based on a positive mode, this design principle is placed below ‘induce paes’. . incorporate attention to aesthetics in organization routines when the organization has chosen to apply the aesthetic perspective, this view, as well as the vocabulary on aesthetics, must be incorporated in daily routines to perpetuate the aesthetic attention. the organization could incorporate aesthetics as a new quality requirement in planning and control mechanisms like reports, strategic decisions, team meetings, and appraisal interviews. so, the daily focus on and discussion about ‘good’ will be supplemented by these about ‘beauty.’ . guard mystery: offer new chances for aesthetic experiences and avoid habituation to beauty and ugliness guarding mystery means deliberately incorporate ambiguity, complexity and 'unsettledness', whereby employees are encouraged to discover and learn. mystery, kaplan et al. (kaplan et al., , p. ) argue, ‘embodies the attraction of the road, the view partially obscured by foliage, the temptation to follow the path, “just a little farther”’. organization scenes continuously should promise the opportunity for employees to reveal new oas and to be continuously surprised by new aesthetic experiences, by incorporate some mystery in the organization. the aspect of mystery is part | developing beautiful organizations widely cited in the literature on aesthetics. in order to keep observers interested (again and longer looking at an art work), the object must offer a degree of complexity, puzzling, problem solving or ‘struggles’ (e.g. leyton and ramachandran, ). guarding mystery can be applied in the object (the organization) as well as in the subject (the perceiver). the organization should continuously offer employees possibilities to discover new stimuli and new fields of interest that effect new aesthetic experiences. like suggested, the four quadrants (coherence, recognition, accomplishment, and collaboration) could be repeated in this single variable for aesthetic experiences by offering layering and depth, as a sort of fractal. because it is quite obvious that employees experience beauty in oas in which those aesthetic properties are recognized. for the subject, the observers, the conducted third and fifth empirical studies demonstrated that enhancing their aesthetic awareness and sensitivity isn’t a one-time effort to keep employees aware of their enactment. the process of priming and reframing which can be done in a workshop needs to be repeated in order to anticipate the habituation of the aesthetic process by employees. employees become ignorant to the daily beauty and ugliness around them. in order to retain and increase aesthetic awareness and sensitivity and to prevent habituation, proposed interventions for enhancing aesthetic awareness and sensitivity need to be repeated occasionally. . increase the chance of a good p-o fit, based on aesthetic value above mentioned design principles are focused on employees who provisionally have chosen to work for their organization. apparently they experience a p-o fit and they probably feel committed to their organization. by improving the conditions - the work and organization design – in order to have more paes and less naes, they will even show aesthetic commitment. one of the results of this dissertation is a list of oas which cause paes which contribute to a positive judgment of organizational aesthetics and the judgment of ´beautiful work´ and these oas contribute to affective commitment of employees. some of these oas are already perceivable before an employee decides to choose to work for an organization. these representational aesthetic properties are important in the process of identification with the organization (e.g. kristof, ; finegan, ; posner and schmidt, ). like discussed in the paragraph before, some of these oas can be redesigned or enhanced in order to achieve more paes and less naes. but some of them cannot be changed because they are fixed or because change is not desired by (some) stakeholders. oas like an organization’s mission, global organizational goals, characteristics of staff (values), a business approach, and rituals can better be displayed and communicated before an employee decides whether to work for the organization. thus, in order to attract the ‘right’ employee and to prevent a bad p-o fit, organizations must display and communicate those oas which have impact on this p-o fit. these eight design principles were tested during five validation workshops. the results are described in chapter . part | developing beautiful organizations part | developing beautiful organizations . design interventions the earlier developed design principles for beautiful organizations are the most important proceeds of this dissertation. in this section examples of and suggestions for design interventions are proposed for applying the design principles in practice, and to provide managers, consultants but also employees practical tools for ‘how to’ beautify organizations. this study aims to provide a first idea of oas in organizations (system aesthetics and result aesthetics) and in work (process aesthetics) which cause paes and naes, and conditions for having aesthetic experiences and the revenues of attention to organizational aesthetics, like affective commitment. the relationship between oas, aesthetic experiences and affective commitment itself can be regarded as one of the design principles expressed in the adapted aet framework. but this design principle only emphasizes the importance of a certain type of solution in view of certain values or goals (´to achieve a, do b´) (romme and endenburg, ). in order to increase positive aesthetic experiences and to decrease negative aesthetic experiences in organizations, interventions are needed. van aken (van aken, , p. ).advocates ‘the logic of the technological rule’: ‘if you want to achieve y in situation z, then do (something like) x.’ he defines this the technological rule as ‘a chunk of general knowledge, linking an intervention or artifact with a desired outcome or performance in a certain field of application’ (van aken, , p. ). this perspective is quite similar to the suggested design logic of romme and endenburg ( ) and zhang ( ) who suggest design propositions or rules and design principles and design guidelines. in this dissertation, following the principles of design science research (e.g. van aken and romme, ), design interventions will be part of design principles which are expressed in cimo- configurations (cimos)(ibid). so, reflecting on this theory, this design phase will end in several design principles expressed in design interventions. they express the generative patterns, a general prescription for the concept or perspective of beauty in organizations to make them more attractive for their employees. the ´prescription´ of the context contains oas in organization design and job design in which employees perceive beauty or ugliness (paes and naes). the mechanism in all cimo´s concerns these paes and naes. the outcome in the cimo´s concerns all possible (perceived) proceeds of attention to beauty in organizations like proud employees, the feeling of ownership, commitment, and work pleasure which are all aspects of affective commitment. the design interventions describe the activities organizations should engage to increase aesthetic awareness and sensitivity by employees, to avoid naes, and to increase paes in organizations. design requirements and design limitations before proposing and describing interventions a global set of design requirements and design limitations were defined for organizations that have the ambition to embed aesthetic value into their organizations design. design requirements can be divided into four types which are preconditions, functional requirements, user requirements, and design limitations (e.g. weggeman, ; wijnen et al. ). preconditions describe the conditions of the environment in which the customized design will fulfill its function. a major precondition for organizations that aspire to embed and exploit aesthetic value in their design is the context in which aesthetic value is needed and applied. attention to organizational aesthetics concerns the business approach and organization principles. this concerns integration into the organization strategy and organization culture (van aken et al., ). because culture expresses organization values (van der wal, ) and strategy can be considered as an elaboration of organizational culture (van der loo, ), the precondition for organizational part | developing beautiful organizations aesthetics can be described as ‘based on organization values’ (combining functional value with aesthetic value). functional requirements describe what the solution should achieve, the design goal(s). therefore, the main requirement of interventions is to improve employees’ organizational engagement (e.g., affective commitment). in order to do so interventions should enhance affective commitment (functional requirement ). another functional requirement could be that (employees and) management wants to increase the need and recognition of aesthetic value within their context (functional requirement ). third, adding aesthetic value to organization design must be durable (functional requirement ) and the benefits should exceed the costs (functional requirement ) in particular for those who suppose that beauty as a goal in itself is not enough, but must be economically profitable. user requirements answer the question ‘what do users like?’. these are the requirements of people who experience and work in organizations that decide to combine functional value with aesthetic value. for now, management will be considered as users who will apply the later proposed design principles for ‘beautiful organizations’. besides management all employees currently working in the organization that decide to combine functional value with aesthetic value should have the attitude and competencies needed to combine both values and to apply proposed intervention (van aken, ). unfortunately literature doesn’t offer specific user requirements for embedding aesthetic value to organizations, and even for organization design at all. but in a broader sense, principles for organization change should be practical, repeatable, flexible, customized, differentiated (focused on culture, structure or on processes), and applied organizational and departmental wide (e.g. weggeman, ; wijnen et al. ). design limitations answer the question ‘what are the boundaries of the method set by the preferred solutions?’ it has its limitations in respect of the design as a result of the selected design methodology (weggeman, ). they determine the boundaries for finding solutions to the design problem. the designer of the interventions often determines these boundaries (andriessen, ). for organizational aesthetics, designed to 'design science research' means: the design is a solution to the field problem (design limitation ), the design contributes to the knowledge of the discipline (design limitation ), and the design is designed only from a players (employees) perspective (design limitation ) (van aken & andriessen, ). concerning design methodology, the design principles will be based on the design fundamentals of roozenburg and eekels (roozenburg and eekels, ) (design limitation ). for the application of most design principles, organizations should take account of a period of at least one year (design limitation ). it should be noted that design limitations should guide the process of design and development. they should not be mentioned in the approach itself because they are explicitly included in the design interventions (weber, ). part | developing beautiful organizations design interventions van aken ( , ) observed that design implementations have numerous hidden properties, which - although present in the implementation itself - are invisible in the design model. an intervention - as part of a cimo-configuration - concerns a concrete activity to solve a field problem, and is characterized by minimal specification. this minimal specification gives the intervention leader several degrees of creative freedom to adapt the design to the requirements of the specific intervention (van aken and andriessen, ). considering the proposed design principles, eight types of design interventions were developed. these design interventions are examples for: . enhancing aesthetic awareness and sensitivity (priming and reframing); . utilizing critical moments and occasions for attention to aesthetics; . applying collaborative and reflexive change methods or design methods; . inducing paes; . avoiding naes; . incorporating the attention to aesthetics in organization routines; . guarding mystery; . increasing the chance of a good p-o fit, focused on aesthetic commitment. initially a list of design interventions is defined. during the testing phase, in the validation workshops for enhancing aesthetic awareness of management and employees, participants were asked to mention interventions - without reflecting on the initial list of interventions - they would apply in their own organization. these interventions are described in section . . . . interventions for enhancing aesthetic awareness and sensitivity (priming and reframing) following the literature on priming and reframing, especially literature about variation and confrontation (e.g. bolman and deal, ), the following two interventions are proposed to develop and implement: a. in (a) workshop(s), reflect on ‘the current awareness and state of beauty’; b. use a simplified edition of the bel-book for collecting aesthetic experiences. these interventions will be explained below. a. in a workshop(s), reflect on ‘the current awareness and state of beauty’ for enhancing employees’ and manager’s aesthetic awareness, a workshop, conducted by an external (an outsider who has the position to confront), has shown to be an effective intervention. aesthetic sensitivity of people is hard to change. but their consciousness and their attention to aesthetics certainly can be influenced (e.g. steinkraus, ; cupchik and laszlo, ; osborne, ; zemach, ). by assessing especially those oas which show strong (canonical) correlation with ‘aesthetic value’, the workshop members will also generate a list of ‘interventions for increasing paes and / or decreasing naes’. the conducted workshops as part of the phase of testing of this dissertation have proven to be successful. the agenda of this workshop is expressed in appendix . if possible, the workshop as input will use the results of the registered paes and naes in the bel- book and /or the results of a survey in which employees of the organization valued their appreciation of oas and scored their perceived revenues of organizational aesthetics. the workshop will also contribute to the understanding of employees of what organizational aesthetics concern and may provide. and it can be an effective way for introducing a vocabulary on aesthetics. part | developing beautiful organizations another method for determining the degree of aesthetic consciousness of the organization is the checklist below (table . ). phase monitoring points status . awareness a. are beauty or aesthetic value recognized and common used terms in the organization? b. does management know what employees perceive as ugly and beautiful in their work and organization? yes no yes no . fit c. is their an opinion that there is too much focus on business economic value and too little on affective value of the organization? d. does management believe that beauty could contribute to good? yes no yes no . development & change e. are interventions developed and implemented which induce positive aesthetic experiences? f. are interventions developed and implemented which avoid negative aesthetic experiences? yes no yes no . securing g. is the role of aesthetic value embedded in daily routines such as pdca- cycle, a quality system and hr-system? h. is aesthetic appreciation of employees measured periodically? yes no yes no . perpetuation i. does management deliberately incorporate ambiguity, complexity and 'unsettledness' in the organization? j. are employees continuously challenged and encouraged to discover aesthetic value? yes no yes no table . checklist awareness organizational aesthetic consciousness in a second workshop, with the same respondents of the first workshop, they are able to reorganize and redesign the existing construct of oas in ways that will enable their organizations to realize new paes. to focus these conversations, participants often use well-known frameworks of organization design such as the mckinsey -s model (waterman et al., ) (on which the esh model is based), or the weisbord -box model (watkins and mohr, ). for all of the selected design elements (oas), participants write ‘provocative propositions’, which are statements that describe oas of the desired organization as it ‘should be’ (barrett and fry, ). b. use a simplified edition of the bel-book for collecting aesthetic experiences the use of the bel-book, initially deployed as a method for data collection, has shown that this method also has a profound effect, and can be considered as an intervention as well. many respondents became more conscious of their paes and naes and of the oas in their daily work environment when registering their aesthetic experiences. as a consequence, their attitude changed more positive towards their organization. a simplified edition of the bel-book, used by a representation of personnel during - days, will probably literally confront them with their part | developing beautiful organizations aesthetic attentiveness. the results can be discussed in the workshop which likely will contribute to aesthetic attitude of all participants as well. . . interventions for utilizing critical moments and occasions for attention to aesthetics the choice for this intervention is particularly based on the results of the first empirical study in which respondents were asked for conditions for focusing on organizational aesthetics. those organizations that recognized and applied the aesthetic perspective subscribe to the importance of utilizing a critical moment. most mentioned critical moments are rehousing /rebuilding, new management, and a changed strategy to a more value driven strategy. . . interventions for applying collaborative and reflexive change methods or design methods for applying collaborative and reflexive change methods or design methods two types of interventions are proposed: ) methods for supporting a collaborative process of change and ) methods of design thinking, and narrative approaches such as appreciative inquiry. first, only stakeholders themselves can judge what they experience as beautiful and ugly and which interventions contribute to aesthetic value in their organization. employees usually constitute the majority in organizations. so, for inducing paes and avoiding naes, interventions should be developed and implemented bottom-up by existing institutions and methods like installed teams for performance improvement and quality teams. quay ( ) suggested also to focus on clients, in partnership with consultants and /or staff, make decisions about what to gather, how and by whom, and should be intimately involved in gathering and analyzing data. also meetings and interviews with employees and involvement of clients with implementation are suggested by quay ( ) as successful collaborative change methods. harris ( ) suggests introducing project teams, parallel teams, and group design. she and beyerlein and harris ( ) particularly emphasize the importance of a collaborative culture, which is characterized by shared responsibilities, and decisions made collaboratively. second, about interventions for applying collaborative and reflexive change methods or design methods. (e.g. avital et al., ; whitney, ; barrett and cooperrider, ; zandee, ). some researchers and practitioners like avital et al. ( ) and whitney ( ) propose to apply the vocabularies and design approach of appreciative inquiry developed by cooperrider. they argue that ‘joining a positive lens on organizing with the transformative power of design thinking opens new horizons and possibilities for creating organizational and social well-being (avital et al., , p. ). zandee ( ) argues that by applying a narrative mode of knowing people give meaning to their lived experiences. fairchild ( ) proposed to introduce the process of dream, play, metaphor, and concept in organizations to design more positive-driven interventions. by discovering ‘what might be possible in organizational life’, using an abductive approach (e.g. kolko, ), playful explorations of important aspects of organizational life enables the discovery of aesthetic experiences (barrett and cooperrider, ). this second operationalized intervention probably needs to be introduced explicitly for example in workshops, because of the unfamiliarity to employees and the learning of a specific perspective and process. part | developing beautiful organizations . . interventions for inducing paes for realizing the three spaces of understanding, relatedness, and exploration, six aesthetic properties need to be developed. earlier five properties for inducing paes are proposed: . reinforce coherence: oas that reveal and strengthen the ‘internal causality’ of the organization, achieved by a degree of aesthetic formal properties such as balance, unity in variety and harmony; . enhance possibilities for identification (recognition): oas that reinforce the possibilities of employees for identification with the organization (which causes value and goal congruence), achieved by a degree of aesthetic representational properties; . condition accomplishment: goal achievement and task completion as well as the process of realizing (goal progress) and learning; . enable collaboration: interaction between colleagues, between management and colleagues and between customers and employees. mystery will be explained separately in paragraph . . , because of its focus on preventing employees´ habituation to beauty and ugliness in their organization. . interventions for revealing and enhancing coherence some scientists and designers (e.g. girod et al., ; scruton, ; leder et al., , kaplan et al., ) emphasize the role of understanding for appreciating coherence. they all suggest to increase transparency and clarity in relations and other aspects of coherence in order to improve coherence. pettigrew and whipp ( ) and hodson and riscigno ( ) particularly discussed coherence and cohesion in organizations. they proved that coherence contributes to organizational effectiveness, to a positive organizational climate and to the maintenance of management legitimacy. they also advocate that organizational coherence positively influences employee citizenship and commitment, cooperative relations and meaning in work. according to childre and cryer ( ) coherence is a progressive state: ‘the more we build it, the more we have in reserve’ (childre and cryer, , p. ). they argue that coherence is consistency (e.g. between customer expectations and customer satisfaction), is continuity (e.g. in every internal process and communication modality), and is balance (e.g. within personal life and of each stakeholder in the process). the conducted first and second empirical studies as part of this dissertation have resulted in at least six oas which are strongly related to the aspect of coherence. these are coherence of things itself, represented by alignment of management with employees, alignment of organization goals with individual goals, internal cooperation, alignment of activities and composition of employees. of course organizations can initially examine whether these oas need to be improved. but the question to respondents in the fifth empirical study to associate most common aesthetic formal properties like grouping , harmony and unity have resulted in an extension of the list of six. grouping and harmony are most often associated with colleagues, symmetry is mainly associated with the building in which they work, unity is strongly related to unity within the team they work and repetition and rhythm is highly associated with work and work schedules. considering the similarities but also the differences of associations between type of professions and the great variety of mentioned formal properties in literature on organizational science, for each organizations it seems to be necessary first to associate mentioned formal properties before developing interventions for enhancing coherence. the components of the esh-model can be used, wherein the coherence between staff, culture, strategy, management style, system and structure, part | developing beautiful organizations can be discussed and improved as well as the coherence within each component. organizational coherence is a quite abstract and not often discussed issue in organizations. therefore, proposed interventions particularly focus on the awareness and elaboration of coherence. considering this, the following three interventions for enhancing coherence are proposed to develop and implement: a. associate and value most common aesthetic formal properties; b. make transparent tasks, positions and processes. a. associate and value most common aesthetic formal properties like practiced in the fifth empirical study, by associating most common aesthetic formal properties, employees become aware of aspects that contribute to the feeling of coherence in their organization. this can be done during a brown paper session as well as by filling in the format which was used during the fifth empirical study (see appendix ). the following aesthetic formal properties were asked to associate: harmony, climax, contrast / variety, symmetry, repetition / rhythm, unity, balance / coherence, grouping, transparency, focus / dominance and dynamic. a first attempt was made by surgeons and teachers during the fifth empirical study. often mentioned examples of associations with formal properties are grouping (mainly associated with colleagues), harmony (harmony within a group of colleagues), symmetry (mainly associated with the building in which they work), unity (strongly related to unity within the team they work) and repetition / rhythm (highly associated with work and work schedules). b. make transparent tasks, positions and processes several researchers and designers (e.g. verweij, ; oxman, , ) suggest to draw schematic representations or to use ontology mapping (jonker et al., ) for expressing aspects of coherence such as alignment of activities or interdepencies between people, and interfaces of interacting roles in order to create more transparency in coherence. more pragmatic interventions for obtaining coherence are ‘define clear goals’, ‘define a collective ambition’, ´describe who is knowing and doing what’ and ‘describe processes and activities’. drawing for example process flows, socio diagrams of a organization morphology not only increase insight in relationships within the organization, but also reveal bottlenecks and interventions for improvements. it would be wise to extent to the list of aspects of coherence with the found oas in the first and second conducted empirical studies. these are: alignment of management with employees, alignment of organization goals with individual goals, internal cooperation, alignment of activities, composition of employees, goal progress, and goal achievement. . interventions for revealing and enhancing recognition this study proved that oas that contribute to identification are important for having aesthetic experiences in organizations. most strongly correlating oas that attributed aesthetic representational properties are employees’ work attitude and qualities, qualities of management and style of management, attitude towards environment, organization philosophy / business approach, offered challenges, development opportunities, organization mission and goals, organization goals, work atmosphere, organization rituals, and internal communication. organizations initially can examine whether these oas need to be improved. according to literature, positive identification causes value and goal congruence, which is mainly experienced by employees in interaction with colleagues and their management. so basically, one intervention seems to be relevant to develop and implement: a. define shared values. part | developing beautiful organizations a. define shared values many researchers (e.g. alvesson and willmot, ) have argued the importance of explicating (shared) morals and values in organizations. posner and schmidt ( , p. ) suggest that ‘having clarity about personal values may be more important, in relation to attitudes about work and ethical practices, than being clear about organizational values.’ therefore, discuss in a workshop most strongly (canonical) correlating values with ‘aesthetic value’ and with ‘affective commitment’, like opportunities for personal development and organization goals. if necessary, cite, explicate or define organization values and goals, relate these to personal values and goals, and discuss in which oas they are most represented or should be. if necessary, use most applied lists of values like those of rokeach or of mcdonald and gandz (rokeach, ; mcdonald and gandz, ). . interventions for enhancing accomplishment this dissertation has proved that accomplishment (goal achievement and task completion) to a very large extent is causing positive aesthetic experiences (paes). because in particular professionals not only want to perform, but also distinguish learning as an important argument for working (e.g. drucker, ; gunderson, ), three conditions seem to be settled in organizations: a. define a collective ambition; b. elaborate and agree conditions for realizing agreed tasks / goals; c. create learning arrangements. a. define the collective ambition literature on goal-setting theory, alignment approach and performance management argue that agreements about personal goals contribute to performance as well as to employee satisfaction (e.g. locke and latham, ; williams, ). many researchers emphasize the importance of elaborating and agreeing personal tasks / goals in relation to organization goals. particularly weggeman ( ) emphasized the importance of defining the ‘collective ambition’ of employees. many other researchers emphasize the importance of differentiation of goals and tasks. based on studies of for example warrick and zawacki ( ) and maister ( ), goals and tasks need to be defined in terms of output or profit, contribution to personal growth, contribution to success of others (colleagues), contribution to customer satisfaction, contribution to organization development, and contribution to the development of a subject or field. examples of important conditions for working with personal goals and tasks are the awareness of usefulness and appropriateness of goals, their feasibility, employee involvement in the determination of goals and tasks, the valuation and assessment, and the agreement on conditions (williams, ). thus, during a workshop, (performance appraisal) interview or ‘bilat’ with (an) employee(s), above mentioned aspects need to be discussed and agreed. b. elaborate and agree conditions for realizing agreed tasks / goals negative aesthetic experiences (naes) could be a reason for discussing conditions for realizing agreed tasks / goals. this dissertation proved that many naes impede goals progress and thus also goal achievement and task completion. after collecting naes and barriers for goal achievement and task completion by using a simplified edition of the bel-book, an interview or proposed workshop, conditions can be discussed for realizing agreed tasks / goals. c. create learning arrangements development opportunities are actually one of the only oas which was mentioned very often, was highly appreciated and shows as well strong (canonical) correlation with both ‘aesthetic value’ and ‘affective commitment’. but how to realize development opportunities? kessels ( ) distinguishes seven learning functions for embedding learning in work environments. part | developing beautiful organizations these are: ( ) subject matter expertise, ( ) problem solving, ( )reflective skills and meta-cognitions, ( ) communication skills, ( ) self regulation of motivation and affection, ( ) peace and stability and ( ) creative turmoil. he argues that ´the policy and the activities that an organization develops to promote these seven learning functions form its corporate curriculum: the plan for learning to increase knowledge productivity by applying new competencies for flexible adaptation´. lappia ( ) more recently emphasizes that learning aims and objectives, learning content, learning activities, a learning facilitator, learning materials and resources, grouping , a learning location, learning time and assessment of learning are the major conditions for work place learning. in each context, a learning facilitator can reflect on these examples of learning functions and conditions. and s/he can select an appropriate intervention for creating and improving learning conditions in his own organization. . interventions for enabling collaboration literature on collaboration, particularly in professional organizations, offers many examples of interventions. beyerlein and harris ( ) propose eight type of interventions or support systems for collaborative settings and supporting references which are (a) leadership, including executive leaders, direct supervision, team leaders, and team members/shared leadership, (b) organization and team design, (c) performance management, including goal setting, performance measurement, performance feedback, rewards, and recognition, (d) financial and resource allocation, (e) learning, including communication, information, knowledge management, and training, (f) physical workspace and tools, (g) integration, including between-teams integration, teams and systems integration, and change initiatives integration and (h) creativity and innovation. a similar list of enablers for collaboration was recently proposed by parry, davies, and lim ( ). but this is supplemented with rewards and incentives as motivators, cooperation of employees with mixed identities and mixed contracts, collective ambition, and development of a social network(s). so, this box of interventions offers inexhaustible possibilities for organizations. the application of interventions is highly dependent on the context, and on the identified problem related to collaboration. therefore, a specific intervention for collaboration has not been recommended, except the reference to the wide range of mentioned interventions. only one global intervention is proposed: stimulate and improve interaction between colleagues and between staff and management. a. stimulate and improve interaction between colleagues and between staff and management employees very strongly perceive aesthetic experiences during interaction with colleagues, management and customers. in these ‘spaces of relatedness´, employees’ values are confirmed which enhance reciprocity. discuss during ´bilats´ and meetings employees satisfaction during interaction. discuss aspects of reciprocity, interdependence, quality of feedback and learning opportunities, its bottlenecks and ideas for improvement. if necessary, embed the aspect of interaction in annually internal satisfaction research and performance appraisals. . . interventions for avoiding naes like conducted in this dissertation, first one needs to know in which oas employees perceive naes. naes can be collected by using the simplified and shortened version of the bel-book in which employees register their naes for a short period. also naes can be collected during the proposed workshop for increasing awareness of the role of aesthetics in work and organizations. it needs to be remembered that some mentioned psychological effects such as prototyping, familiarity, and verbal overshadowing will have effect during registering aesthetic experiences by respondents. therefore, the chosen method for collecting naes should be complemented with a list of most found naes in this dissertation to which employees respond in terms of degree of aesthetic appreciation and degree of emotional impact. most mentioned naes are: no or less influence or part | developing beautiful organizations control, not functioning ict, bad acts of management, bad acts and/or bad interaction with colleagues, bad interaction with customers, less or no involvement with planning, and barriers for goal achievement. . . interventions for incorporating the attention to aesthetics in organization routines to keep attention to initiatives concerning organizational aesthetics, these should be incorporated into daily routines of employees and managers must institutionalize these interventions so that aesthetic value indeed will be combined with functional value in the organization (kotter, ; edmondson, bohmer, and pisano, ). many interventions can be introduced for incorporating such initiatives. examples of these interventions are: a. add the role of beauty in the plan-do-check-act-cycle (pdca-cycle); b. add ‘beauty’ as a requirement for quality and performance. a. add the role of beauty in the pdca- cycle an expression of the scientific management paradigm in organizations is the widespread use of the deming pdca cycle (plan-do-check-act/adapt). at different levels in the organization, such as project management, meetings, and strategic policy, this thinking is widespread embedded with a strong focus on effectiveness and efficiency. variation and confrontation with the aesthetic paradigm and becoming more conscious of paes and naes can easily be conducted by adding one simple question to this pdca cycle and to daily operational work: ‘is it or was it beautiful?’ or ‘does it have aesthetic value?’. just by making the agreement to regularly ask this question, it will increase awareness of the role of aesthetics in work and organization. or more specific and related to the pdca-cycle: plan: do we plan beautiful things and goals? do: are we doing beautiful things in a beautiful way? check: is it beautiful (enough)? act / adapt: are we continuing doing beautiful things in a beautiful way? / how can we do beautiful things in a beautiful way? b. add ‘beauty’ as a requirement for quality and performance many organizations adopted quality systems, implemented key performance indicators (kpi’s), and work with goals defined in terms of effectiveness, efficiency, flexibility and / or innovation. they all exclude motivational needs of employees. by adding ‘beauty’ as a requirement for ‘good’, the attention to aesthetics in the organizations can be secured. for operationalizing ‘beauty’, those properties or qualities which are proposed for inducing paes can be used, which are recognition, coherence and accomplishment. . . interventions for guarding mystery guarding mystery can be applied in the object, the organization, as well in the subject, the perceiver. the results of the empirical research have shown that employees get used to beauty and ugliness in their organization. a part of guarding mystery focused on the subject, the employee, should prevent their habituation to beauty and ugliness in their organization. it is likely that when management and employees are conscious of the beauty which surrounds them, they or in particular management should have attention to ) keep employees aware of the daily beauty in their work and organization and ) make the organization even more beautiful. interventions for keeping employees aware of the daily beauty in their work and organization are initially discussed in the section about interventions for priming and reframing. a workshop, the use of a simplified bel book, a company visit or an asked reaction about organization’s aesthetic value from a visitor or customer could effect an increased aesthetic value for the employee without changing something in the organization. part | developing beautiful organizations but in order to create conditions for employees to keep them intentionally conscious of their aesthetic attitude and to explore continuously cues for aesthetic experiences, organizations can do more. stimulating aesthetic experiences to employees also can be achieved by changing the object, the stimuli, they observe. based on this research, organizations should encourage employees to discover aesthetic value in those stimuli in which they recognize coherence and recognition and which offers possibilities for accomplishment and interaction. therefore, the four quadrants (coherence, recognition, accomplishment, and mystery) could be repeated in the single cell of mystery. as third, the importance of ambiguity for keeping workers attentive, interested, and involved is advocate by much research (e.g. beardsley, ; leyton, ;'s leather et al, ; zain et al, ; benson and brown, ; sennet, ). already leonardo da vinci distinguished ´sfumato’ (the willingness to embrace ambiguity, paradox, and uncertainty) as one of his ‘seven da vincian principles’(gelb, ). learn to navigate the edges of two fields (sennett, ), learn to deal with role-ambiguity (benson and brown, ) and ´create some “unsettledness” to maintain complexity and openness as long as possible to delay the moment when things become "fixed" in chosen forms´ (zandee, ) are some examples of ambiguity found in literature. concerning organizational aesthetics, organizations could realize ambiguity by deliberately exploring the boundaries between functional value and aesthetic value. particularly those oas that do not per se contribute to good (see table . ) can intentionally embrace ambiguity, such as autonomy, variety of work, or offered challenges. or intentionally deploy the opposite of mentioned key characteristics of inducing paes which means temporarily realizing decoherence, defying personal values and goals, and disturbing the daily conditions for accomplishment. thus, three types of interventions are proposed: a. prevent employees’ habituation to beauty and ugliness in their organization; b. offer new possibilities for new positive aesthetic experiences (paes); c. embrace ambiguity. the first intervention can be applied by regularly collecting and discussing paes and naes of employees. for offering new possibilities for new positive aesthetic experiences of employees, they should be provided with new stimuli that trigger aesthetic experiences and by creating new spaces of understanding, relatedness and exploration. the empirical studies have shown that employees in particular experience aesthetics triggered by stimuli such as colleagues, organizational coherence or personal development. interventions like new formation of teams, change of workplace or job enrichment or change of job level could offer employees new possibilities for new positive aesthetic experiences. for offering ambiguity could be realized by avoiding perfectionism, enticing employees to come out of their comfort zone or by having problems, and challenges designed by employees themselves. part | developing beautiful organizations . . interventions for increasing the chance of a good p-o fit the following intervention is proposed to develop: a. discuss organizational identifiability during a job interview(s). many organizations have described their business ethics explicitly in their business principles. in order to increase the chance of a good p-o fit based on identification, organizations must also describe explicitly these oas (aesthetic properties) which have strong impact on employee’s aesthetic commitment. offering these on the organization homepage as well as handing over these to applicants during a job interview must increase the chance of a good p-o fit based on aesthetic values. oas that are needed to be described and discussed are: composition of staff (gender, age, education, values, ambitions) characteristics of work atmosphere (organization culture) testimonials of employees about internal cooperation development opportunities organization philosophy and business approach pictures of our workplace and interior organization mission organization goals (globally), especially the contribution to environment organization values style of management examples of organization rituals part | developing beautiful organizations . . composing arrangements of interventions below (table . ), an overview of all proposed design interventions is drawn in a list. the interventions are related to the design principles and include references to sources. design principles design interventions ‘how to’ (tools) reference . enhance aesthetic awareness and sensitivity (priming and reframing) a. in a workshop(s), reflect on ‘the current awareness and state of beauty’; b. use a simplified edition of the bel-book for collecting aesthetic experiences. wall of paes during meeting workshop checklist (see table . ) self-report shalev and bargh ( ), hatchuel ( ),zandee ( ), watkins and mohr ( ), neilsen ( ), schön ( ), Östman ( ), beardsley ( ), schwarz and clore’s ( ), bolman and deal ( ), little ( ) . utilize critical moments and occasions for attention to aesthetics a. exploit changes like rehousing / rebuilding, new management and a changed strategy to a more value driven strategy. -- kotter ( ) . apply collaborative and reflexive change methods or design methods: a. exploit existing performance improvement / quality teams b. stimulate narratives and methods like appreciative inquiry quality teams workshop appreciative inquiry hatchuel ( ), zandee ( ), (watkins and mohr, ), neilsen ( ), schön, ), avital et al., ( ), whitney ( ), zandee ( ), fairchild ( ), barrett and cooperrider ( ) . induce paes enhance possibilities for identification (recognition): a. define shared values workshop lists of values (rokeach, mcdonald and gandz or schwartz) kelman ( ), chatman ( ), weggeman ( ) ashkanasy ( ) reinforce coherence a. associate and value most common aesthetic formal properties; b. make transparent tasks, positions and processes. brown paper (see appendix ) use schematic representations, ontology mapping, process flows, socio diagrams hodson and riscigno ( ), childre and cryer ( ), simon ( ), schön ( ), hanson ( ) condition accomplishment a. define a collective ambition b. elaborate and agree conditions for realizing agreed tasks / goals c. create learning arrangements workshop, (performance appraisal) interview or ‘bilat’ self-report, interview or workshop seven learning functions of corporate curriculum learning facilitator locke and latham ( ), weggeman ( ) williams ( ) kessels ( ), lappia ( ) part | developing beautiful organizations design principles design interventions ‘how to’ (tools) reference enable collaboration a. stimulate and improve interaction between colleagues and between staff and management interventions or support systems for collaborative settings and supporting references beyerlein and harris ( ), parry, davies and lim ( ) . avoid naes a. collect (causes for) naes wall of naes during meeting workshop self-report fredrickson ( ), baumeister et al. ( ), amabile and kramer ( ) . incorporate the attention to aesthetics in organization a. add the role of beauty in the plan- do-check-act-cycle (pdca-cycle); b. add ‘beauty’ as a requirement for quality and performance. pdca-cycle quality systems, implemented key performance indicators (kpi’s) and work with goals von bonsdorff ( ) . guard mystery: retain and increase aesthetic awareness and sensitivity: a. prevent employees’ habituation to beauty and ugliness in their organization; b. offer new possibilities for new positive aesthetic experiences (paes); c. embrace ambiguity. beardsley ( ), leyton, ( ) leather et al, ( ), zain et al, ( ), benson and brown ( ), sennet ( ) . increase the chance of a good p-o fit, based on aesthetic value (shared values): a. discuss organizational identifiability during a job interview. list of oas that are needed to be described and discussed weggeman ( ) table . overview of interventions organizational aesthetics these interventions were tested in workshops as part of the validation phase of this dissertation. the results are described in chapter validation. above mentioned nineteen design interventions describe the full range of opportunities for organizations to compose aesthetic arrangements. by using the verb composing organizations is directly referenced to design disciplines is which aesthetic value is clearly acknowledged as a design principle and is utilized in design interventions. compose literally means place or put together (com ponere in latin). each organization has its own characteristics. depending on the context (c), the characteristics of the organizational design and the events and also the needs of employees, specific interventions are required for the operation of a specific mechanism and for the realization of certain outcomes (pawson and tilly, ). a set of interacting parts or a combination of multiple interventions collectively lead to the solution of the problem (pawson and tilly, ; weber, ). the challenge for every organization is to compose specific aesthetic arrangements and aesthetic practices (ranciere, ) for inducing and safeguarding paes in their organization. reymen ( , p ) suggests to make representations of the design: ‘a reproduction of a relevant subset of properties describing the artifact being designed is a mental image, a picture as textual description, or in some other way. in design disciplines, other than organization design, morphology is an often used technique for composing arrangements of interventions. morphology, the study of pattern and form is able to make the link between design and its consequences (hanson, ). it could help a designer to overlook complexity and synthesis and to develop design alternatives and part | developing beautiful organizations decisions (simon, ). so, after discussing the role of aesthetics in organizations, the organization could start with a wide scale of interventions. to help the organization with this process of composing and choosing appropriate interventions, they could use the overview expressed in appendix . this overview of questions offers design principles and their relations with the design parameters of the esh-model. it is very likely that these questions will are recognized by management. examples of questions are ‘do employees represent work attitude qualities, collegiality, contacts with customers, development opportunities and internal cooperation the values of employees?’ and ‘is management style supportive to internal collaboration?’. part | developing beautiful organizations part | developing beautiful organizations . indications and contra-indications the proposed design principles have been developed to reform, (re)design, create, or enhance and sustain professional organizations that decrease negative aesthetic experiences (naes)and increase positive aesthetic experiences (paes) of professionals with the goal to increase their affective commitment. this section describes the indications and contra-indications for these design principles. most of these indications and contra-indications were identified during the α-test conducted in validation workshops in five organizations which are described in section . but they are described below considering these indications and contra-indications as part of the development of beautiful organization. these indications and contra-indications need to be taken into account during application of the developed design interventions in organizations. . . indications during the first empirical study, managers of ten organizations were interviewed who showed interest in aspects of organizational aesthetics without knowing the theory of this subject. the statements below express their attitude towards the perspective. ´wonderful research! fits with the way we are working in our organization.´ ´”beauty in organizations" is a provocative book. it responds to the growing interest in a more high- quality way of organizing´ all managers together mentioned stimuli (oas) of the organizations in which they experience beauty. the most cited oas are interior / exterior (mentioned by %), people orientated management (mentioned by %), influence of staff (mentioned by %) and personal development of employees (mentioned by %). they all are convinced about added value of the perspective and its positive contribution. the most frequently cited outcomes are good image of the organization (mentioned by %), high customer satisfaction (mentioned by %), high employee commitment (mentioned by %), proud employees (mentioned by %) and positive feedback about the organization from the environment (mentioned by %). during the α-test, conducted in workshops in five organizations, participants were asked more explicitly for indications for applying organizational aesthetics. most mentioned indications were ‘attention to aesthetics positively effects work experience, quality, productivity and/or organization improvement’ ( times), ‘the perspective is causing more motivated employees’ / ‘this makes me happy, what makes me perform better’ ( times). thus, it is noteworthy that many participants of this research without hesitation consider the aesthetic perspective as a method for organization improvement. apparently they do not struggle with the distinction between the ethical and aesthetical judgment made in literature; beauty should even provide something in favor of employees and the organization. therefore, the organizational aesthetic perspective could be more explicitly communicated as a perspective or even a method for organization improvement. part | developing beautiful organizations . . contra-indications during the acquiring of organizations and respondents for the fieldwork and for the test phase, several arguments, in particular confusions, were mentioned. these arguments can be considered as contra-indications which should be taken into account by managers and consultants by addressing and applying organizational aesthetics. ´what do you mean with the concept of aesthetic ´ is the most asked question. below, a paragraph of one of the received emails is cited, which expresses the reactions of most people. ‘your request makes me curious. it is not clear to me what you want to do and what the benefits are for my organization. in itself, i am very interested in anything that can lead to organizational improvement, on the other side, my organization and the employees are currently under very high pressure and then a total time investment of to hours is a lot. moreover, i want the participants to benefit from their participation.’ in addition, two published books on this subject caused some comments from readers on the internet: ´who feels the drive to focus on beauty, i recommend reading this book´ ‘now customer orientation is increasingly important for organizations it is in my opinion time to have responsibility for organizational aesthetics. customers simply choose organizations in which beauty is experienced and seen’ although these comments are quite positive, they also can be considered as contra-indications. both express first the need for receptivity for this new perspective. during the α-test, conducted in workshops in five organizations, participants were asked more explicitly for contra-indications for applying organizational aesthetics. although all participants are positive about organizational aesthetics and its possible outcomes, some of them mentioned some contra-indications (mainly attributed to management) for not applying the perspective in their organization. ‘other priorities’ and the ambiguity of the term ‘aesthetics‘ were most mentioned contra-indications. reflecting on those reactions, two main contra-indications should be considered: ) confusion of what organizational aesthetics concerns and involves ) and confusion about its benefits. confusion of what organizational aesthetics concerns and involves a frequently heard contra-indication concerns the uncertainty about the meaning of organizational aesthetics. ‘aesthetics and beauty seems to be container concepts, hard to define’, respondents often argued. in many cases people associate beauty with beauty or beautiful experiences outside their work. many times they asked, "do you mean the flowers at the reception office or our new interior?”. this phenomena can be related to the aspects of familiarity and prototyping. familiarity refers to how familiar or novel an object is (mastandrea, bartoli and carrus, ). prototypicality is the part | developing beautiful organizations amount to which an object is representative of a class of objects. it is built through experience, and a prototypical object optimally represents a class of objects (leder et al., ). the explanation of aesthetics used in the bel-book, after testing, was considered as satisfied by the respondents: ‘a thing, event or moment that made you feel “that’s beautiful!” (or ugly) directly or during reflecting at the end of the day.’ recommended is to communicate organizational aesthetics as a new perspective on organizations which offers a new repertoire of interventions for organizational change and improvement. by considering work and organizations through an aesthetic lens, the repertoire of interventions for improvement will increase. by focusing on the coherence of things in organizations, on identifiability with values, goals and products and services and on conditions for accomplishment, the aesthetic perspective can even contribute to commitment of employees and to their performance. confusion of its benefits because of the strict separation made in literature of the ethical judgment and the aesthetic judgment and desired disinterestedness of beauty, the potential benefits of organizational aesthetics initially have been narrowed to positive emotions among employees which contribute to their affective commitment to the organizations. literature study has shown that affective commitment is the strongest predictor of organizational outcomes like employee retention, absenteeism, intensions to quit the organizations, customer-oriented behavior and performance (meyer et al., ; allen et al., ; meyer smith, ; rhoades et al., ; shivangulula, ; rego et al., ). antecedents of affective commitment are feelings of ownership, pride, work pleasure and flow experiences which are all mentioned by respondents as perceived outcomes of attention to organizational aesthetics and which can be confirmed by quantitative analysis in this dissertation. thus, for those organizations which doubt to apply organizational aesthetics, and for those managers for whom beauty because of beauty is not enough, there are strong indications that attention to organizational aesthetics offers many positive effects, even economic effects. the elimination or decrease of both contra-indications can be achieved by interventions focusing on priming and reframing. priming is the phenomenon whereby a recent experience activates the memory and behavior and unconsciously influences this behavior (e.g. tulving et al., ; kolb and whishaw, ).reframing is the effort to change the dominant thought (frame) and action (bryan et al. ; bolman and deal, ; smith en huntsman, ).kolko ( ) suggests six steps for reframing: ) identify the initial frame; ) determine the levels of specificity of the identity, context and embodiment; ) create blank reframing indices; ) reframe; ) extrapolate likely user goals and ) extrapolate design implications. in chapter some suggestions are mentioned for future research in which these contra-indications are included. part | developing beautiful organizations part | validation validation testing the design principles and interventions is part of the cycle of design science research (dsr) (van aken and andriessen, ). dsr usually consists of one or more case studies, in which the generic solution is tested. this means that the current practice will navigate several times the practice stream (van aken and andriessen, ). this is preferably done after the other, the serial case study, for possible interventions to best fit. van aken ( ) therefore speaks of an "evolving series of case studies”. the cycle of testing and adjusting is hereby passed so often, until the generic solution is completed (theoretical saturation)and sufficient evidence is gathered for its activities. this process can be preceded by an “inventory series of case study(s)” to identify problems and to look for good examples of solutions (interventions) (van aken, ). unfortunately, applying all developed design principles and realizing and measuring their intended effects will take at least several months. for example, the effects of decreasing naes by improving influence or control or the conditions for goal achievement will only become visible after months in organizations. the effects of increasing paes by reforming aspects of the coherence of things in organizations probably will be noticeable after a long period as well. for these two types of design disciplines, only the first attitude of managers and employees towards proposed interventions can be evaluated. tan ( ) suggests to validate design principles and interventions by a group of experts, stakeholders, and potential users when testing in practice is not possible. but this option is difficult to realize, because hardly anyone is experienced in the implementation of design principles and interventions for adding and enhancing aesthetic value in organizations. only the effect of interventions for strengthening aesthetic awareness by management and employees (priming and reframing) can be measured within a few weeks in an α-test. therefore five workshops were conducted in five different organizations. . validation of interventions . . workshops for enhancing aesthetic awareness organizations functional requirements for these workshops were participating dutch professional organizations, a group composition of - professionals, attended by at least manager. five participating organizations ( water boards, a business unit as part of information management of the shared service center of the dutch police, a business unit of the ministry of social affairs and employment and an education centre for highly gifted students) were randomly selected, and mainly chosen because of their willingness to participate. goals and process the content and the agenda of these workshops are described in appendix . the goals of these workshops were divided into two types: goals for the organization and goals for the researcher. goals for the organization were ) to enhance employees’ aesthetic consciousness and their attention to aesthetics (priming and starting reframing); ) to achieve a same language and reference to organizational aesthetics; ) to determine whether organizational aesthetics could be a fruitful perspective for their organizations and ) if yes, to select first ideas of design principles and interventions. especially for the researcher the workshops were conducted for three other goals: ) to test the recognizability and usability of the list of interventions; ) to collect indications and contra-indications for applying organizational aesthetics and ) to select effects of the workshops for the participants. as part of the process of priming and reframing, before the workshops started participants were asked part | validation to register three beautiful and ugly aspects of their work and/ or organization. they were also asked to value the list of twelve most strongly correlating oas with the judgment ‘beautiful organization’. this list was one of the major results of the conducted empirical studies. the two and a half hour lasting workshops consisted of a combination of a presentation and discussion based on five open-ended questions: ) what was your first reaction to the previously asked questions about beauty and ugliness in your organization?; ) what do you experience as beautiful and ugly in your work and organization?; ) which of the showed design principles for beautiful organizations will you apply in your organization?; ) which actions or interventions will you apply in your organization? ) which two arguments do you have for starting or rejecting the idea of organizational aesthetics in your organization?; ) what has been the effect of the workshop for you? the invitation, agenda, used presentation and assignments for the workshops are supplemented in appendices and . results the results of the workshops are divided into four types: initial reactions of participants, selected design principles and interventions, indications and contra-indications for applying organizational aesthetics and effects on participants. initial reactions of participants the process of priming and reframing already started before the workshop by asking participants to register three beautiful and ugly things in work and/or organization and to value organizational aesthetic stimuli (oas) which most strongly correlate with the judgment ‘beautiful organization’. before discussing the results, the participants were asked to argue their initial reaction during answering these questions before participating in the workshop. statements like ‘the questions triggered me’, ‘the questions were never asked me before’ and ‘they forced me to think why i really go to work’ represent most given answers. selected design principles and interventions participants were asked to select design principles of which they think they are consistent with to their organization strategy. design principle ‘applying collaborative change and design methods’ was mentioned times and was mentioned by all (participants of) organizations. ‘induce paes’ was mentioned times, by of five (participants) of organizations. ‘reinforce coherence’, ‘stimulate interaction’ and ‘condition accomplishment’ as part of ‘induce paes’ were all mentioned times. ‘avoid naes’ is the fourth often mentioned design principle (mentioned times by all organizations). ‘guard mystery’ is the fifth often mentioned design principle (mentioned times by of organizations). appendix expresses all data of the workshops. remarkable is that most participants quite easily and naturally adopted a new language they faced. in many discussions during the workshops participants used the terms ´paes´ and ´naes´. during discussions, participants argued that the application of design principles is related to the state of organizations aesthetics and the degree of attention for this perspective in the organization. reflecting on the scores of participants on organizational aesthetic stimuli (oas) which most strongly correlate with the judgment ‘beautiful organization’, all participating organizations show strong satisfaction for these oas. therefore, their attention to the most important oas like style of management or alignment of activities, although not considered from the aesthetic perspective, was already high. therefore most mentioned design principles concern the phases design and change or even the phases fit and perpetuation of the mentioned change process. the respondents argued that the proposed design principles were sometimes hard to apply because of their abstract nature. easier, they argued, was proposing pragmatic and operational interventions or actions. part | validation participants suggested interventions which covered of the proposed interventions in chapter . design of this dissertation. beside these interventions, participants suggested new interventions. most frequently mentioned interventions are enhance organization’s aesthetic consciousness (mentioned times), improve interaction between employees (mentioned times; with more employees and better quality of interaction), improve coherence (mentioned times) and elaborate and align employees’ values and goals with organization values and goals (mentioned times). all these interventions where mentioned by participants of three or more organizations. and all these interventions are proposed in chapter . design of this dissertation. two proposed interventions were not mentioned or associated by the participants. these are ‘add “contribution to organizational aesthetics” to the hr-cycle’ and ‘describe organizational identifiability during a job interview’. most mentioned new interventions participants suggested are: improve internal communication ( times), improve autonomy (mentioned times), celebrate success (mentioned times), and (re)design workplaces (both mentioned times). reflecting on those mentioned new interventions, they all, except ‘celebrate success’, are part of the list of collected oas in the conducted first and second conducted empirical studies. but only ‘improve internal communication’ contributes to the unconscious sense of a ‘beautiful organization’; only this aspect (oas) of the newly mentioned interventions strongly correlates with the judgment of a ‘beautiful organization’. the application of these newly mentioned design interventions should be examined in future research. interesting is whether these interventions are related to the design principles the participants mentioned earlier. these relationships are expressed in appendix . there seems no relationship between chosen design principles and mentioned interventions. only the interventions ‘stimulate and improve interaction between colleagues and between staff and management’ and ‘make coherence transparent and value links and interdepencies’ show some relationship with the selected design principles. for all other proposed interventions, participants selected interventions which do not show any relationship with earlier chosen design principles. remarkable is that participants suggested interventions which mainly concern inducing paes, and much less those which concern avoiding naes. during discussions, many participants mentioned that they experience focusing on positive aspects as more satisfying than focusing on negative aspects, even after being told that from literature is known that negative emotions (caused by naes) are stronger (more impact and longer lasting) than positive emotions (caused by paes). also interesting is whether suggested design interventions respond to the aspects participants perceived as ugly before the workshop. only for one organization some relationship can be discovered between two aspects. the other organizations proposed interventions which do not show a direct relationship with aspects the participants perceived as ugly. this confirms the result of the chosen design principles. participants more often selected the design principle ‘induce paes’ than the design principle ‘avoid naes’. indications and contra-indications for applying organizational aesthetics participants were asked whether they would start to apply organizational aesthetics in their organization and which arguments they have for a ‘yes’ (indications) or a ‘no’ (contra-indications). all participants together mentioned arguments for ‘yes’ and arguments for ‘no’. most mentioned indications were ‘attention to aesthetics positively effects work experience, quality, productivity and/ or organization improvement’ ( times), ‘the perspective is causing more motivated employees’ / ‘this makes me happy, which makes me perform better’ ( times). although all participants are positive about organizational aesthetics and its possible outcomes, some of them mentioned some contra-indications (mainly attributed to management) for not applying the perspective in their organization. ‘other priorities’ and the ambiguity of the term ‘aesthetics‘ were part | validation most mentioned contra-indications. effects on participants at the end of the workshops, participants were asked about the effects for themselves of the workshop. in total effects were recorded. of them concern ‘good feeling’ (‘nice to talk about my work and organization this way’), of the reactions concern a changed attitude (‘the workshop triggered me’, ‘”beauty” can positively affect “good”’), reactions concern new knowledge and new insights (‘organizational aesthetics could be a new perspective to improve organizations and to satisfy employees as well’, ‘it offers new possibilities’), and of the reactions concern activation of participants (‘i will recommend the workshop to my management’, ‘we really should start with this perspective’). so, it can be concluded that the conducted workshop really enhances employees’ aesthetic consciousness and their attention to aesthetics (first goal). many times participants mentioned that discussing this subject with their colleagues and experiencing the same (positive and negative) aesthetic experiences was very satisfying. eight participants suggested to repeat the workshop for colleagues and management. most participants have a strong belief that if their management is receptive to the aesthetic perspective (stage of awareness), they naturally go through the following phases of design and change and perpetuation. also the second (to achieve a same language and reference to organizational aesthetics) and even the sixth goal of the workshops (effects on participants) have been achieved. conclusions this α-test concerned the test of one design intervention, which is the workshop for enhancing employees’ aesthetic consciousness and their attention to aesthetics. this workshop can be considered as successful in many respects. all participants were positive about organizational aesthetics and its possible outcomes. it should be said that it is probable that many of the participants signed up for the workshop because of their interest. they mainly experienced increased knowledge, a changed attitude and good feeling (workshop goal ). collected indications mainly concern the possible positive effects on employees and their organization (workshop goal ). during discussion they recognized and developed a same language and reference to organizational aesthetics, and they all determine that organizational aesthetics could be a fruitful perspective for their organization. also can be concluded that participants hardly recognize and establish the relationship between design principles and interventions, although most of the mentioned interventions cover the list of proposed interventions. nevertheless, the recognizability and usability of the proposed list of interventions (workshop goal ) largely can be confirmed. finally, it is noteworthy that almost all participants without hesitation consider the aesthetic perspective as a method for organization improvement. apparently they do not struggle with the distinction between the ethical and aesthetical judgment; beauty should even provide something in favor of employees and the organization. part | validation . . the bel-book another proposed intervention for enhancing employees' aesthetic consciousness and their attention to aesthetics’ is the bel-book (beauty experiences log book). this bel-book was used during empirical research for collecting daily aesthetic experiences. the bel-book was tested during the third empirical study. respondents were asked to reflect on the use of the self-report. they responded mainly positively and the method was used again in a modified version during the fifth empirical study. both studies showed that the aesthetic awareness of users increased only by having repeated attention to the organizational aesthetic stimuli which cause aesthetic experiences. so, the use of the simplified edition of bel-book is validated. . consequences for design results of this α-test have some implications for the proposed design, particularly for the proposed interventions and for the arguments for applying organizations aesthetics. the initial list of proposed interventions is largely confirmed, but is updated to better understand language and is supplemented with some new interventions for applying some design principles. for example, ´collect and share paes´ obviously is considered as a more pragmatic intervention for enhancing aesthetic awareness of employees. or ´define shared values´ and ´define the collective ambition´ are obviously considered as more recognizable than ´elaborate and align employees´ values and goals´. the mentioned arguments for applying organizations aesthetics (indications) as well as the mentioned contra-indications show that the translation of the two blocks ‘value’ and needs’ of the design fundamentals of roozenburg and eekels ( ) to ‘function’ is defined much more specific in chapter . design. by participants mentioned outcomes of organizational aesthetics like positive effects for employee satisfaction, product and service quality, productivity and performance are included in chapter . design. and also the interpretation of the design principle ‘utilize critical moments and occasions for attention to aesthetics’ has been defined more specifically based on these arguments. . suggestions for future validation 'design science research’ attaches great importance to α-and ß-tests as part of the design process. an α-test examines the design in a controlled environment, often the natural environment of the researcher. the researcher is itself part of the area. in an α-test errors, omissions and application problems are detected. it is a form of co-creation with customers, or potential users, for example colleagues’ critical thinking along with the researcher. this is only done for the intervention 'workshop for enhancing employees' aesthetic consciousness and their attention to aesthetics’. this intervention could be conducted (and ß-tested) in future by organizations themselves, as suggested by the participants of the workshops. for testing the other interventions, only some of them can be conducted in a controlled environment and in presence of the researcher (α-test). this concerns only interventions whose effects on a short term, within days or weeks, are clear like a session for defining shared values or a (collective) goals and visiting other organizations for reflection on own organization for the other interventions, their effects can only be determined after a period of some months or even years. this should be tested (ß- and γ-test) in future research. in a ß-test a design is tested by third parties (van aken, ). the purpose of a ß-test is to determine whether the design is effective for what it is designed. in a ß-test people from the target group apply the design for a certain period in their own environment and report their experiences. part | validation so, for validating most interventions, agreements with organizations should be made which will apply some of these interventions. after some months effects of these interventions possibly can be evaluated. part | reflection reflection the aim of this research was ) to describe and conceptualize organizational aesthetics and to examine antecedents (e.g., stimuli and properties) and consequences (e.g., employees’ affective commitment) and ) to generate design principles to develop, redesign and sustain an organizational design for professional organizations that improves employees’ organizational engagement (e.g., affective commitment). in the next sections will be reflected on both research goals (section . ), on the design process (section . ) and on the design (section . ). finally, section . reflects on the scientific and practical relevance of this research, and the meaning of this dissertation for myself. . reflections on the design process design goal for this dissertation, the research question was concerning a design goal. in the third chapter the defined design goal is to develop design principles for professional organizations which will increase paes and decrease naes to employees which contribute to their affective commitment. eight design principles have been developed that are defined and discussed in the fifth chapter. these eight design principles have been developed with the use of the cimo-logic (e.g. , van aken, ; denyer et al., ). the answer to the design goal, in term of this cimo-logic is: if design principles for beautiful organizations are applied in professional organizations, the change of increasing paes and decreasing naes will contribute to their affective commitment. the reason to start this dissertation was the lack of empirical data about aesthetic experiences in organizations and the absence of principles and interventions to increase paes and to decrease naes of employees which will contribute to their affective commitment. whether proposed design principles will realize these goals in organizations is hard to tell. only one of the proposed interventions, in a workshop increasing aesthetic awareness, was tested. the effect of the other principles and interventions will be clear after a longer period. the conducted α-test was too limited, but this test offered many indications that these design principles are quite promising for achieving the design goal. new research is needed to test this more appropriately. reflection on the combination of theories this dissertation started with a holistic perspective on organizational aesthetics by conducting a literature study on three topics: aesthetics, organization design and emotions in organizations and the aspect of affective commitment. in not much literature on organizational aesthetics such a broad perspective on this subject has not been described so far. the literature on aesthetics offered many theories about object-subject interaction, aesthetic properties and the aesthetic process which have been proved to be actual and relevant in a organizational context as well. particularly roozenburg and eekels´ ( ) developed design fundamentals of product design constitute the basis of the new developed organizational aesthetics framework and design principles. one of the insights literature on aesthetic offered was the aesthetic supervenience aspect. this theory simply claims that aesthetic properties are embedded in non- aesthetic properties. which made clear that literature on organization design must be studied to collect design parameters for organizations which can be considered as non-aesthetic properties. literature on organization design indicates that the aesthetic perspective affinities with present developments in organizations. literature on emotions in organization was studied after discovering that aesthetic judgments also effect emotions to the observer which are strongly effecting his behavior in an organizational context, particularly his affective commitment to the organization. by discovering the aet framework part | reflection developed by weiss and cropanzano ( ), many loose insights of the three disciplines came together in one validated framework. and second, the extensive literature research resulted in several research methods such as the bel-book and the affect grid. concluding, starting with a holistic perspective on organizational aesthetics was time-consuming but valuable. and resulted in a solid theoretical basis on which the empirical research could be initiated. reflection on the empirical research the focus of this dissertation was to obtain knowledge about organizational aesthetics in practice in order to develop design principles that support professional organizations to increase paes and to decrease naes to employees which contribute to their affective commitment. with only some suggestions made in literature, empirical research was a challenging experience. the constructed lists of most mentioned, highest appreciated and strongly correlating oas, and particularly the differences between these lists, expresses the richness but also the difficulty of the conducted empirical research. finally, by using the innovative method of canonical correlation analysis, the relationship between organizational aesthetic stimuli and aesthetic value and affective commitment was demonstrated. so, in retrospect, the empirical conducted research was a sort of quest. or like suggested by van aken ( ), an “inventory series of case study(s)” to identify problems and to look for good examples of solutions. each empirical study could be considered as a "evolving series of case studies”. the cycle of testing and adjusting was hereby passed so often, until the generic solution was completed (theoretical saturation) and sufficient evidence was gathered for its activities. inductively deriving insights from empirical data engaging with other theories (about aesthetics, organizational design and employee commitment) an organizational design for aesthetics in organizations evolved (urquhart, ). looking back to these empirical studies, and now understanding the effects of some psychological mechanisms like familiarity, the mere exposure effect and verbal overshadowing, the next time when conducting empirical research the aspect of priming as well as using indirect questions and gathering aesthetic experiences by earlier using self-reports is recommended. so the order of empirical studies should be adjusted. in order to obtain a complete list of oas for the quantitative study (supplemented with goal achievement, receive recognition, and goal progress), it would be better first to collect all type of aesthetic experiences, both on organizational aspects and experiences during events. for measuring respondents aesthetic judgment as well as the emotional impact of aesthetic experiences the affect grid used in the fifth empirical study should be added to the survey. these lessons can be used in future after concluding there was initially nothing to build on for this dissertation. reflection on design methodology 'design science research' is an approach that has proven to be able to create solutions for management and organizational problems in scientific context and to develop designs that would otherwise be created by practitioners in the field. nevertheless, it can be concluded that design principles as a result of a scientifically established design study, deliver reliable solutions for practical problems. reliability refers to the degree to which a repetition of the same study will provide the same results. it is based on the assumption that there is a reality that, if repeatedly studied with a reliable instrument, leads to the same result (merriam, ). because of this assumption, during the validation workshops (as part of the α-test) participants were explicitly asked about effects and less about the application of the design principles. these modes of inventory characterize a degree of subjectivity. therefore it seems advisable to perform a test-β and γ-test. the purpose of a β-test is to determine whether the design "acts" for which it is designed, by obtaining more robust and objective evidence provided by a third party (van aken, ). the researcher plays an active role in the β-test. an γ-test allows people to use the design indefinitely and offers them the opportunity to report any problems they encounter to the designer (ozer, ). this test can be part | reflection obtained by directly answering the question whether the field problem effectively is solved with this design,. that is also what 'design science research' aims at: generating knowledge to solve field problems (van aken, ). refection on the knowledge stream and practice stream the main objective of the design sciences is to develop general knowledge that can be used for solving. specific field problems. this general knowledge is developed by means of testing solutions in real-life situations. in design science research, the knowledge stream and the practice stream are supposed to be intertwined (andriessen, ). these two streams have different participants (versus principal investigator), different objectives (generating knowledge versus social systems change), different types of learning (reflective versus regulative) and different solutions (knowledge about a solution concept versus solutions) (stam, ). this entanglement brings some issues with it (mulder, ). on two of these points is reflected in this section. actually, thus the proposed model itself (the knowledge stream) is also tested in its application in practice (the practice stream). first will be reflected on the role of the researcher in this intertwinement of streams. the researcher is supposed to defend his or her design and at the same time continue to doubt its accuracy from a distance. the practice stream requires a close connection with the context-specific problem, while the knowledge flow requires a critical attitude and distance. this may lead to an awkward position of the researcher. adapting to the practice stream (self-adaptation ') is not only varied with the autonomy (self-preservation), but also takes place simultaneously. this means that a researcher should not have to develop a design, but also disposes of skills to advise on how to implement the design. he must be able to operate in both worlds effectively, but also must be able to keep a critical distance to both. his role is close to a consultant (stam, ; mulder ). a second area of interest is the entanglement of the practice stream and knowledge stream. design science research aims at developing knowledge to solve a practical problem. this second area of interest arises when the researcher is moving from the design phase to the testing phase. the researcher is explicitly in contact with "the real world" and he or she is a kind of consultant. the researcher is confronted with issues that are closely related to the field problem, but which do not belong to the defined research domain. which stream is given priority: the knowledge stream (in which developed knowledge must be generalizable) or the practice stream (in which a problem has to be solved)? stam ( ) argues that the importance of the problem agent-in-question transcends the importance of the researcher and thus determines the development of design knowledge subordinate solving the problem. during α-testing of the design principles this topic was actually discussed. some participants asked for facilitation by the researcher to reduce work pressure or to persuade management to have attention for human aspects of an upcoming reorganization. considering whether or not to respond to this request has to do with an essential element of β-testing (mulder, ): the absence of the designer during application, so potential blind spots of the designer regarding its use become visible (argyris, ). the requested service is not provided. in this dissertation and for this dilemma, the knowledge stream is given precedence over the current practice. thus, reflecting on both streams and in particular on their entanglement, the role of the researcher in the practice stream is difficult because of the necessary changed role of the researcher. therefore, it would be wise for design science research to focus on a β-test as long as this permits curbing the curiosity of the researcher. part | reflection generalizability of results the mission of design science research is to generate knowledge professionals can use to create solutions for their field problems (van aken, ). the result of design science research is a principle solution (van aken, ). because that solution has been established in a specific context, it is required to transport this specific solution to generalize knowledge. this has been done in this dissertation by using the cimo-logic (see chapter ). this logic is based on a linear causality thought: an intervention is a trigger for mechanism which causes an outcome. for applying organizational aesthetics, organizations that do not exploit the opportunities of organizational aesthetics (c) in which organizational aesthetic properties are adjusted (object-oriented interventions) and /or employee’s awareness and perceptions of organizational aesthetic properties are influenced (subject-oriented interventions) (i) cause increased attention to (organizational) aesthetics (m) which will increase aesthetic value to / and affective commitment of the employee (o). reflecting on the mentioned stimuli (oas) that cause aesthetic experiences, it can be concluded that whatever the context characterizes like type of sector, organization size, type of services, in all these type of organizations the stimuli in which employees perceive aesthetic value are quite similar. and even more important, the reason why employees are having aesthetic experiences in all these different contexts, the type of aesthetic properties such as coherence, accomplishment, collaboration, recognition, and mystery which are accommodated are similar. thus, the principle solution, expressed in the proposed eight design principles, can be considered as generalized knowledge (interventions) which can be applied in different organizations (context). limitations of research a first limitation of this research is the limited number of organizations that contributed the empirical research. the small degree of standard deviation in quantitative data and the great similarities of qualitative data show that future research can build on these data with sufficient trust. but with some caution, the results could be applied in types of organizations which were not part of the group of selected organizations, like family firms, small firms and production firms. the differences between some of the acquired data of teachers and surgeons show indications that context and work influences the perceptions of aesthetic value. as part of the mentioned context, the degree of organizational development, or more specific the degree of ‘good’ of organizations needs to be considered in future research. the relationship between good and beauty, between the ethical and aesthetical judgment, seems to be difficult to grasp. a second limitation is that the various empirical studies as part of the empirical research were conducted in different organizations. although the data of the organizations per empirical study are more or less equal, ideally the interviews with managers, as well as the questionnaires and the bel- books are completed by respondents from the same organizations, whereby much better different types of data could be compared. unfortunately this was not possible because none of the organizations wanted to take part in more than one empirical study. an important third limitation is the only partial validation of the set of developed principles and proposed interventions. only two of nineteen interventions were tested: the bel-book and the workshop for enhancing aesthetic awareness. for the other interventions, their effects can only be determined after a period of some months or even years. therefore, a least a ß-test needs to be conducted. part | reflection . reflections on the design reflection on design principles and interventions design science research is a method of design-oriented research, based on the regulative and reflective cycle (van aken, ). one of the stages in the regulatory cycle is the phase ‘plan (design)’ (see section . ). in this phase, data of theory and empiricism are converted into design principles. this is a creative process and therefore not entirely objective. in this creative phase eight design principles are proposed during the workshops, the α-test, participants reflected on these design principles and on related interventions. most cited design principles are (in most mentioned order): induce paes, apply collaborative change / design methods, avoid naes, guard mystery and enhance aesthetic awareness (see results of the workshops). based on the discussion about all interventions, it can be concluded that all proposed design principles are understandable. reflecting on the collected interventions and their relationship with design principles, it can be concluded that most mentioned interventions support the proposed design principles. but a relationship between both isn’t clear. there seems no relationship between chosen design principles and mentioned interventions. only the interventions ‘stimulate and improve interaction between colleagues and between staff and management’ and ‘make coherence transparent and value links and interdepencies’ show some relationship with the selected the design principles. for all other proposed interventions, participants selected interventions which do not show any relationship with earlier chosen design principles. this relationship, thus, what in practice does not show obvious relationship, should be further examined in future. reflection on position and application domain the current literature on organizational aesthetics seems to be an isolated discipline. the subject was hardly connected to existing theories such as organization design and emotions in organizations. the conducted literature study has connected organizational aesthetics to these theories and translated this into an organizational aesthetics framework. the insight that an aesthetic perspective on organizations could be a new approach for business and performance improvement, in particular perceived during the validation workshops, offers new challenges for organizational aesthetics. by focusing on functional beauty, by improving coherence and representation of values and goals and to a lesser extent by focusing on accomplishment, a broader repertoire of interventions is offered for organizations to achieve improvements. reflection on the name almost directly from the start of the study, stakeholders such as friends, respondents and other researchers often asked about the meaning of concepts such as beauty, beautiful aesthetics and in particular in relation to organizational design. "what do you mean”, they asked often. "does your research concern the physical design of organizations? “. again, like earlier observed, the previously described psychological mechanism of familiarity affect respondents’ reactions. they associated beauty, and organizational aesthetics in almost all cases with their daily and familiar 'encounters' with this subject and struggled to translate into a work and organization setting. but just as important, results of this study like the found aesthetic properties in the found oas which effect aesthetic experiences and the influence of personal characteristics on the aesthetic judgment, can be traced back to the principles of aesthetics. the lengthy discussion of the distinction between good and beautiful in the context of organizations has led to a reconsideration of the interpretation of the subject. but only during the validation workshops, after participants called it "just a new method for organization improvement”, showed that at least for this group 'users' a pragmatic goal appeals most. part | reflection for science this dissertation can be grouped to the knowledge on organizational aesthetics. for operators in organizations such as managers, employees and consultants it should be considered to speak more in terms of an approach for organization and performance improvement. . relevance of the dissertation scientific relevance as noted in chapter , there is relatively little literature on organizational aesthetics. most of the publications argue the idea of organizational aesthetics, describe in which stimuli aesthetics possibly is hidden and why an aesthetic perspective on organizations could be a fruitful new approach. in this literature, any case-descriptive or empirical investigation was missing. design principles for organizational aesthetics are scientifically designed and offer a holistic approach to organizations. validation with users indicates that it is possible to connect the science with practice of organizational aesthetics. indeed, the most important results and relevance of this research can be summarized as: . aesthetic experiences in organizations contribute to affective commitment and indirectly to performance; . a confrontation of organization design with aesthetics and emotions in organizations which proved that aesthetic experiences in organizations are triggered by stimuli which contain aesthetic properties in particular coherence, recognition, mystery and accomplishment (climax). these properties are similar to those that trigger aesthetic experiences in the arts and in other design disciplines in which aesthetic value naturally is addressed as part of the design. so, triggers for aesthetic experiences in working life seem to be quite similar to those in the arts. . aesthetic judgments (the level) of employees decrease over time because of habituation to oas (familiarity & prototyping) and can be increased by improving the aesthetic awareness of employees. empirical research on organizational aesthetics is quite new. therefore, validated research methods for collecting and valuing aesthetic experiences in practice hardly exist. another important revenue for science are two validated research methods: the bel book, ultimately expanded with the affect grid and the survey of organizational aesthetic stimuli (oas). design principles for organizational aesthetics are designed from a perspective of aesthetics, organization design and emotions in organizations. design-oriented research in which aesthetics is applied to organizations has not been conducted before and is in this sense quite new. at the end of chapter , a new model for organizational aesthetics is proposed, which is build by the design fundamentals of roozenburg and eekels ( ) combined with affective events framework of weiss and cropanzano ( ). the model is slightly modified based on the results of the empirical research. in this model, affective events influenced by characteristics of organizations and personal characteristics effecting affective commitment are presented as a black box. by describing mechanisms caused by an intervention that affects an outcome, the black box opens (van aken, ). this creates understanding of the operation of the model. this insight is relevant for developing new approaches to (re)design and improve organizations and could be adopted by approaches like quality management, business process redesign, performance management and organization design. organizational aesthetics do not represent one of these ‘schools’, but could be adopted by all of them. part | reflection practical relevance organizational aesthetics can be of great value in the general development of new forms of work and organizations, where 'command and control' management is replaced by forms that trigger mechanisms that affect motivational needs of employees. this dissertation has shown that there is an alternative perspective conceivable for (re)designing and changing organizations. we arrived on a critical point in the development of organizations that will force us to explore what possibilities there are next to continue on the same path (reductionist thinking and work). do we choose to stay part of the ‘machine organization’ or the ‘hedonistic treadmill’ or do we embrace the aesthetic perspective? first, the conscious decision to recognize and embrace a paradigm shift must be recognized by stakeholders (academics and practitioners). continue on the path of reductionists and ‘scientific managers’ is a choice, considering the aesthetic perspective also. this dissertation has proved that applying an aesthetic perspective will satisfy employees’ needs. and above all, it is important that for this critical point, the options and the choice is not limited to a select group, but also realized and experienced by such individuals, project teams, divisions, departments, stakeholders, trade associations and client organizations. they can facilitate this process and provide space for self- organization. people and groups can learn what actions are successful and which are not. shared aesthetic values will become visible and translated into design adjustments until a new equilibrium between good and beauty is created. the major practical relevance of this research is the development of design principles and interventions which managers, employees and consultants can use to beautify organizations. by applying the organizational aesthetic perspective, the principles may become clear for improving organizations. these principles, translated into interventions, can be used in the daily practice as a means to think about situations and corresponding interventions. the cases from the validation workshops give examples. although these examples and other proposed interventions do not explain exactly what a person must do in any situation, they contribute to the underlying mechanisms. this organizational aesthetic perspective can serve as inspiration in daily practice. in addition, this study generated a new repertoire of interventions for improving organizations and their performance in a more attractive way. personal reflection as noted in the first chapter, i started this dissertation from wonder and curiosity. curious about whether employees experience beauty in their work, in what and how. not the doctorate but finding answers was my main drive. and of course developing a science-based approach as an alternative for the dominant plan-and-control and functionality-focused approach in current organizations. in this process of research, four breakthroughs should be noted. first, the combination of theories from aesthetics, organization design and emotions in organizations, in particular the discovery of the design fundamentals of roozenburg and eekels combined with the affective events framework of weiss and cropanzano, which offered the basis of a new organizational aesthetics framework. without previously having learned this way, studying literature on aesthetics offered a lot of aha-erlebnises that reminded me of the years at the design academy in eindhoven. second , all those questioning faces that turned into enthusiastic faces during the empirical research i will never forget. many seeds were sown during many interviews and group sessions. “i’m not the only one” i thought many times. these small breakthroughs have been the beginning in many organizations to start with a organizational aesthetics and have cultivated ambassadors for other organizations . a third breakthrough was the explanation for the differences between the three lists of organizational aesthetic stimuli (the most frequently cited, the highest appreciated and the most strongly correlating part | reflection oas). e-mail contact with professor helmut leder (freie universität berlin) and with professor rolf reber (university of bergen) put me on the track of some psychological mechanisms like familiarity, mere exposure effect and verbal overshadowing. before this dissertation, i had not expected that the psychological literature could have such a strong impact on this dissertation. therefore, enough bases were found to continue with one of the lists and to discover the strong agreements with the laws of aesthetics which were initially restricted to the (applied) arts. the last breakthrough actually was caused by respondents during the validation workshops. most of them were convinced that an organizational aesthetic perspective could not only contribute to organizational improvement, but also achieve this in a attractive way. like i did, respondents did not hesitate to bet beauty in favor of good. then of course, as part of a personal reflection, raises the question whether the organization, the process and the results of this research were perceived as beautiful. reflecting on the main stimuli perceived in work that cause aesthetic experiences, particularly offered challenges, qualities of management (read promoters) and working on the same goals are strongly recognized. stepping into the pristine green meadow of organizational aesthetics was scary but very challenging. but without the possibility of clinging to earlier empirical research, support from my companions mathieu weggeman, joan van aken and michel van der borgh on this trip was essential. this can also be described as challenging, because the gentlemen both approached the research differently. having exploited the best of both sometimes was time-consuming but offered a rich palette of insights for continuing the process of thinking. above all, the many sessions were considered very valuable because of the convergence of actions and thoughts. we all believed and still believe that organizational aesthetics could be an important new approach for organizations to enter the future. and then of course the aspect of goal achievement and accomplishment. probably each phd-candidate will recognize the process of despair, the struggle with the english language, spilled energy and loneliness, but also offered energy after breakthroughs and substantiated choices. but i’ve accomplished! the path to the application of organizational aesthetics can now be embarked. part | reflection . suggestions for further research suggestions for further research arise from limitations of this study, from a number of research results and from the validation workshops. the suggestions for further research can be divided into the design principles and interventions, emotions caused by aesthetic experiences, the position of organizational aesthetics, the application domain and leadership. design principles and interventions 'design science research’ attaches great importance to α-and ß-tests as part of the design process. an α-test examines the design in a controlled environment, often the natural environment of the researcher. the researcher is itself part of the area. in an α-test errors, omissions and application problems are detected. it is a form of co-creation with customers, or potential users, for example colleagues critically thinking along with the researcher. in a ß-test a design is tested by third parties (van aken, ). the purpose of a ß-test is to determine whether the design effects for what it is designed. in a ß-test people from the target group apply the design for a certain period in their own environment and report their experiences. the effects of proposed design principles and interventions for beautiful organizations are tested partially, and only during an α-test. not has been tested for example whether organizations should focus on decreasing naes before putting effort in increasing paes. also collecting ideas to awaken and guard mystery need to be examined in future to determine their effectiveness. only one of nineteen interventions (enhancing aesthetic awareness of employees) was tested (α- test)in the workshops with some employees of three organizations. for the other interventions, their effects can only be determined after a period of some months or even years. this should be tested (ß- and γ-test) in future research. because of the perceived unclear relationship between proposed design principles and interventions, this relationship should be better examined. interesting is why employees choose interventions with other underlying design principles than those design principles they had chosen in advance. as part of this research, the effect of conditions for aesthetic experiences such as limited information, time (period of maturation), social activity (derivation) and relation with other different objects being frequently noted should be more deeply examined. a last aspect of design principles and interventions to examine in future is the role of aesthetic properties. it is quite clear that like in other design disciplines such as architecture and product design mainly formal properties and representational properties in oas effect aesthetic experiences to employees. in this dissertation, after collecting oas, these oas were categorized along the type of aesthetic properties and differentiated into specific properties of beautiful organizations such as coherence and accomplishment. new research could examine this relationship vice versa, by examining which formal properties like balance, harmony, peak shift, contrast are perceived in which oas. aesthetic experiences and emotions aesthetic experiences result in an emotion based on an aesthetic judgment (beautiful - ugly) and a degree of emotional impact and arousal. in this study a affect grid was used for positioning both variables. this affect grid was based on russell, weiss and mendelsohn ( ) who combined a degree of pleasure with a degree of arousal. also like russell, ward and pratt ( ) (their dimensions-pleasure- displeasure and degree of arousal-denote matrix and like watson, clark and tellegen ( ) (their the panas-circumflex) they used the common list of emotions. future research could examine whether the new applied affect grid used in this phd-study provokes similar or different emotions like above mentioned researchers discovered. selecting a most applicable part | reflection emotion from a standard list of emotions could be an additional question while collecting aesthetic experiences in practice. position organizational aesthetics can be considered as a new perspective on organizations which offers new design principles and interventions for enhancing organizational change and performance improvement. but this perspective is unknown to managers and consultants and it competes with other approaches such as quality management, business process redesign, cultural changes programs. an interesting question for future research is how organizational aesthetics are related to other approaches for enhancing organizational change and performance improvement. functional beauty the distinction between aesthetic value and functional value in organizations is delicate and hard to determine. this dissertation offers some first indications for criteria for aesthetic value such as disinterested interest and a degree of presence or attribution of aesthetic properties accommodated by oas. further research could examine more in detail which oas contribute to aesthetic value as well as to functional value and which oas don’t. application domain participants of this dissertation covered a wide range of organizations. although they all concerned professional work, the influence of characteristics such as size, variety of processes, products and services and the degree of organizational development on the application of organizational aesthetics were not been examined. the found differences and agreements between the appreciation of organizational aesthetic stimuli of different type of professionals need to be examined further. a second aspect of the application domain is the possible range of observers. this research focused on aesthetic experiences of employees. an interesting future research question could be whether customers and cooperation partners have similar aesthetic experiences as employees based on the same organizational stimuli. aesthetic leadership intuitively, those organizations which contributed to this dissertation which could be considered as ‘beautiful practices’ are blessed by inspiring leaders. the aspect of leadership has not been particularly examined. but in almost all cases of beautiful organizations, only one director decided to apply another perspective for change and improvement. to these directors, without reading anything about organizational aesthetics by them, i didn’t need to explain what organizational aesthetics was. for further research it would be very interesting to examine which characteristics of the manager and leadership will contribute to cherish and apply organizational aesthetics. part theorizing beautiful organizations part | literature study on organizational aesthetics | introduction introduction this dissertation aspired to develop, redesign and sustain an organizational design for professional organizations which decrease negative aesthetic experiences and increases positive aesthetic experiences of professionals. for applying aesthetics in organizations, aspects of organization design have been studied in literature. and more specific translated into following research questions: what are most important parameters of organization design, particularly of professional organizations? what characterizes ‘modern organizations’ and to what extent does attention to organizational aesthetics fit within these organizations? which principles of organization design and organization development can be used to apply organizational aesthetics? for understanding aesthetic experiences of employees, literature on aesthetics has been extensively studied. most important research questions on this topic were: in which stimuli and through what qualities in these stimuli do people have aesthetic experiences? what characterizes the aesthetic process? what personal characteristics of the observer influence his aesthetic judgment? what characterizes design principles of design disciplines such as architecture and product design, in which functional value and aesthetic value are inextricably combined? the literature study on aesthetics showed a strong relationship between aesthetic experiences and emotions. for example seo, barrett and bartunek ( ) emphasize the important role of antecedents and consequences of affective experience (moods and emotions) in organizations in relation to the commitment of employees. strati ( ) distinguishes the pathos (the dimensions of feeling in organizations) in organizational life. so, based on the insights of this part of the literature study, a third topic has been studied in literature, namely the role of emotions in organizations, particularly the role of affect in work and affective commitment. most important research questions for this part of the literature study were: what is the relationship between aesthetic experiences and emotions in organizations? how can aesthetic experiences be related to organization’ outcomes such as employee commitment, satisfaction and performance? this literature review also intended to prepare field research to focus the research questions answered. therefore a ninth research question was added for the literature study: which methods are suitable for examining aesthetic experiences in practice? during examining all three fields of interest, in particular methods for collecting and valuing aesthetic experiences have been studied. part | literature study on organizational aesthetics | introduction part | literature study on organizational aesthetics | aesthetics aesthetics this dissertation is concerning about aesthetics in organizations. therefore the basic principles and insights of the field of aesthetics needed to be examined before possibly transferring these to the field of work and organizations. it would be too simply to cite an overview of the field of aesthetics. taking the view of an organization into account especially the main aesthetic theories, like the aesthetic process, aesthetic quality and property and aesthetic judgment. this section is divided into the following paragraphs: . aesthetic theory . aesthetic experience . aesthetic quality and property . experiencing beauty . aesthetic process . aesthetic judgment . conditions for aesthetic experiences . aesthetic supervenience . aesthetics in design disciplines . conclusions . aesthetic theory the term ‘aesthetic’ was introduced in by the german baumgarten who derived it from the greek aisthanomai, which means perception by means of the senses. better known or better constructed definitions of aesthetics are the following (stecker, ): ‘an artwork is something produced with the intention of giving it the capacity to satisfy aesthetic interest’. famous aesthetician beardsley ( ) argues that ‘a work of art is an artifact which under standard conditions provides its percipient with aesthetic experience’. according to schlesinger ( ) is an artwork ‘any creative arrangement of one or more media whose principle function is to communicate a significant aesthetic object’. aesthetics has been discussed for centuries, started with plato’s and plotinus’ earliest thoughts about this subject in the middle ages. main contributions on aesthetics were made in de eighteen century by kant, hume and hegel. kant´s aesthetics in kant ( - ) wrote his famous critique of aesthetic judgment. most important contributions kant made are that beauty or sublimity is not really properties of objects, but ways in which observers respond to objects. he also claimed that judgments of taste are both subjective and universal. they are subjective he argued because ‘they are responses of pleasure, and do not essentially involve any claims about the properties of the object itself’. he advocated that aesthetic judgments are universal and not merely personal, because they must be disinterested. which means this non-aesthetic interest is extraneous to the appreciation of the art work. for aesthetic judgments to be both subjective and universal, kant argued, ´they had to be about form´. ´beauty should be "a question merely of the form". more specifically, the object being contemplated (e.g., a work of art, or a landscape) ´must display a kind of undefined purposiveness, such that it seems to be organized with a final purpose in mind, although it is not possible to say what that purpose is´. ´thus a work of art, or a beautiful natural object, displays a kind of free play of forms, consistent with the presence of a purpose to which we don't have access´. part | literature study on organizational aesthetics | aesthetics hegel´s aesthetics hegel´s ( - ) contribution to aesthetics was influenced by the ideas of kant. but in his work, from the phenomenology of spirit through the lectures on aesthetics, hegel backed away from kant's thoughts , and proposed a more rational position, in which he did not involve intuition and emotion as the arts do. he recognized three main stages of art history: symbolic, classical, and romantic art. these themes are defined by the relationship between idea and form that is common within it. in the symbolic stage, ‘a powerful idea is expressed in a variety of forms that are felt as not really adequate to its expression. the form is distorted in the attempt to accommodate the transcendent power of the idea’. hegel exemplified the classical stage by classical greek sculpture. ‘the perfect, idealized human form embodies the ideal without any sense of distortion. but while the perfection is evident, the depth of the idea expressed is limited’, he argued. the romantic stage stresses the essential. by using images, hegel continued, ‘it often emphasizes the inadequacy of the image to carry the idea, now apprehended more adequately in an inward way’. hegel developed a particular arts hierarchically, from those most related to image and the physical, and most tied to symbolic art, to those most suited to the self-realization of spirit. a famous claim of hegel about art is that art comes to an end. ‘as spirit reaches its full self-realization, the need for images and symbols withers away, and with it goes the need for any art that uses physical means to express itself’, he argued. he did not meant by this that art would stop altogether, but rather that ‘the need for it, and its role in the development of spirit would be fulfilled.’ hume’s aesthetics hume ( - ) further developed the idea of taste, which dominated the discussion about the arts in the eighteenth century. by talking about taste rather than about objective beauty, aestheticians shifted the focus of from the qualities of the work (the objective view) to the experience of the viewer (the subjective view). in his "of the standard of taste", hume attempts to reconcile two contradictory notions. one, it seems clear that tastes differ. each person decided, without discussion, what he or she experiences and beautiful and ugly. but hume also noticed that taste is not a completely relative matter after all. he mentioned the example of shakespeare for everyone would agree that shakespeare is a greater author than john grisham. bach is a better composer than the dutch composer wagenaar, and so on. ´even if someone could be found to defend the opposite opinion, and no doubt someone could, "no one pays attention to such a taste…; we pronounce [it]…absurd and ridiculous", hume argued. standards of taste, he advocated, represent a consensus, derived from experience, about "the common sentiments of mankind”. this can be related to kant’s subjective universality. another characteristic of taste is the test of time. ‘what has been received as great by many generations of appreciators must be great, for universal human sentiment approves it’, hume argued. a second major statement hume made is about aesthetic sensitivity of the observer. ´strong sense, united to delicate sentiment, improved by practice, perfected by comparison, and cleared of all prejudice, can alone entitle critics to this valuable character; and the joint verdict of such, wherever they are to be found, is the true standard of taste and beauty´ he stated. part | literature study on organizational aesthetics | aesthetics in relation to organizational aesthetics, kant’s subjective universality and the aspect of disinterestedness had first implications for organizations. in that context, subjective universality claims that only employees together can claim what they perceive as beautiful and ugly in their organization. the aspect of disinterestedness is interesting in organizations because of the question whether beauty and ‘good’ can be distinguished separately. hume´s contributions show that also in organizations the distinction between object (aesthetic properties in stimuli in organization and work) and aesthetic experiences of individuals must be made. two main perspectives looking back on the several contributions on aesthetics, two main perspectives can be distinguished which divides the esthetician theorists in two camps: the subjectivist view and the objectivist view (reber et al., ). the objectivism view (based on plato) claims that beauty is a property of an object that produces a pleasurable experience in any perceiver. this objectivism view is characterized (e.g. by thinkers like acquinas, birkhoff, gombrich, arnheim) by the opinion that a human’s mind psychological attempts to identity critical contributors to beauty like balance and proportion, symmetry, informational content and complexity, contrast en clarity. this aesthetic formalism perspective is described as follows. ‘art is daily assessed in terms of reputation and self-expression unit. formalism resistance to this idea and wants it to see artwork from all measures that are purely artistic. which depends on the artwork, irreducible, autonomous phenomenon must be considered on its intrinsic value must be considered’ (van den braembussche, ). formalism in the twentieth century had an inestimable influence not only on modern art, but also on art criticism and the various arts (van den braembussche, ). kant stands at the cradle of the formalism, because only the pure form (‘not darkened by emotions, concepts or whatever’) he considered the experience of beauty provides. kant argued the aspect of the beauty of ‘internal causality’, ‘internal efficiency’ and of ‘internal complexity’, mainly referring to nature by mentioning characteristics such as regularity and symmetry. ‘internal causality’ requires that ‘the parts exist only in relation to the whole’ and that ‘parts undertake to the whole because they mutually cause and consequence of each form’ (veenbaas and visser, ). ‘an organic construction in which both all purpose and means’. in aesthetics, it’s not about the 'what' of the painting´, kant argued, ´but the ‘how’, not the 'content' but of form´. formalists, restrained by bell and fry, claim that not the content, the sensory elements of an art work, is built - line, color, space, light and shadow - but the formal relationship between these elements, the form of the whole, the significant form, causes aesthetic experiences. (van den braembussche, ; stecker, ). according to bell ( ), ´a significant form is a form what possess it with a special sort of value (‘significant form are unilluminating’) that consists in the affect produced in those who perceived it´. so second, if objects other than artworks can have form in the relevant sense, formalists aspire to find something special about the way artworks possess such form. formalists built on a theory of psychology. in this the field, the investigation of beauty was mainly associated with gestalt theory. wertheimer, köhler and koffka defined the principles of the ‘good gestalt´ and examined its application in various fields. ´a good gestalt´, they argued, ´expresses order, regularity, simplicity, stability, and continuity´. and later, lehar ( ) introduced so called gestalt principles as the principles of emergence, reification, multistability, and invariance. the most significant, according to lehar, is the property of emergence, ‘whereby a larger pattern or structure emerges under the simultaneous action of innumerable local forces.’ koffka ( ) suggested a physical analogy of the soap bubble to demonstrate the operational principle behind emergence. ‘the spherical shape of a soap bubble is not encoded in the form of a spherical template or abstract mathematical code, but rather that form emerges from the parallel action of innumerable local forces of surface tension acting part | literature study on organizational aesthetics | aesthetics in unison’ (lehar, ). ´reification is the ‘constructive, or generative aspect of perception identified by gestalt theory’ (ibid). ‘reification is seen in visual illusions, where the subjective experience of the illusion encodes more explicit spatial information than the stimulus on which it is based’, he says. ‘reification in perception indicates that perception is not merely a passive process of recognition of features in the visual input, but that perception creates the perceived world as a constructive or generative process.’ multistability is seen in a variety of visual illusions. ‘the significance for theories of perception is that it reveals perception as a dynamic system whose stable states represent the final percept’ (lehar, ). a central focus of gestalt theory is the issue of invariance (lehar, ). this means ‘how an object, like a square or a triangle, can be recognized regardless of its rotation, translation, or scale, or whatever its contrast polarity against the background, or whether it is depicted solid or in outline form, or whether it is defined in terms of texture, motion, or binocular disparity.’ invariance can also be considered in the perception of color and brightness, where the color of an object is generally judged independent of the color of the light falling on it. this formalistic view have been criticized. first, it rules out the possibility of bad art, since significant form is always something to be valued high. second, it displays the common vice of choosing one important property (the formal property), for which we value art, while ignoring or limiting other properties. and third critique is that formalism excludes presentational features, like watching the sun set (stecker, ). hanslick ( ), who examined musical formalism, said that music is understood as ‘forms moved through sounds’. ‘the various movements contained in the musical surface , hearing how they develop form each other, respond to each other and work towards resolution and closure’ (cited by scruton, ). ‘the pleasure that it causes in not unlike pleasure of pattern in architecture, especially the kind of pattern that is achieved against awkwardnesses and obstacles’ (ibid). hekkert ( ) argued, related to the formalistic view, that ‘if certain patterns in the environment contribute to the function of our senses, it is reinforcing to expose ourselves to these patterns’. the subjectivist view on the contrary, states that beauty is ‘a function of idiosyncratic qualities of the perceiver and all efforts to identify the laws of beauty are futile’ (reber et al., ). taste cannot be debated, following the social constructivist emphasis.’ the claim that ‘beauty is in the eye of the beholder’ represents this subjectivist view, reber et al. ( ) argued. both views are also indicated as the epistic and phenomenological perspective on aesthetics. ´epistic´, argued by dickie ( ), ´means a conception of a non-inferential way of coming to know something; only objects can be coherent, complete and also experiences, not transferred´. the phenomenological perspective, comparable with the subjectivist view, is advocated by dewey, and later beardsley ( ) is introspective: the complex, intense and unified (coherent + complete) object is transferred to the experience. merleau-ponty ( ) and much later ingarden ( ) tried to fill a gap by proposing the interactionist perspective. they reject the objective versus subjective distinction, but suggest that a sense of beauty emerges from patterns in a way people and object relate. aestheticians have been arguing these two main concepts for de recent decades, which ends up into a intellectual battle between two camps. mothershill ( ) speaks about ‘aesthetics, past as well as present, as a intellectual wasteland, and the fault lies with the aestheticians themselves , who have been insensitive to the variety and flexibility of the language of criticism and the use to which it will put.’ this dissertation doesn’t aspire to contribute to the discussion on these different perspectives neither to refute these. during this study, both perspectives have been taken into account. studying the part | literature study on organizational aesthetics | aesthetics theories of aesthetics hopefully will contribute to insights for employing and transferring these into the field of work and organizations. so, let’s start elucidating the subjectivist view first by clarifying the aesthetic experience. this research has shown that both the formalistic view as well as the subjectivist view are recognized in organizations. aspects of harmony and balance as well as different appreciation of aesthetic properties because of taste differences are observable in organizations. so, the mentioned battle can be omitted in that context. . aesthetic experience the subjectivist view on aesthetics claims that the aesthetic experience of the perceiver should be the central focus during examining aesthetics. first will be described the aesthetic experience itself. second, the characteristics of the perceiver will be pointed out. speaking about aesthetic experiences suggests there are other types of experiences people have by perceiving a work of art. urmson ( ) argued that ‘aesthetic experiences cannot be differentiated from other modes of experiences’, such as those characteristic of an intellectual, imagination, moral, or economic interest, by a special class of objects or by a special feature in the objects upon which it is directed or by having a special feeling or emotion among its constituents (osborne, ). some insist (like bell, danto and wolheim) using the technical term designating a range of valuable experiences. others, like urmson and beardsley, find its primary application in a type of sensory experience. while others (scruton and levinson following kant) argued that ‘in an experience in which intellect and imagination as well as, at least usually, the senses are engaged’ (stecker, ). what characterizes an aesthetic experience? what makes the object in an aesthetic experience an aesthetic object? literature on aesthetics offers a lot of definitions. the most cited and applied definitions will be mentioned in the following paragraphs. let’s start with the ’founder’ of aesthetics, baumgarten. he stated that ‘aesthetic experiences provides visceral, holistic, and greatly rewarding sensations that are ordinarily absent from pure cognitive activities’ (baumgarten, ). dewey ( , ) who agreed with baumgarten completes these yields with mental health and greater social well-being. according to dewey: ‘an experience occurs when a work is finished in a satisfactory way, a problem solved, a game is played through, a conversation is rounded out, and fulfillment and consummation conclude the experience. in an experience, every successive part flows freely. an experience has a unity and episodes fuse into a unity, as in a work of art. the experience may have been something of great or just slight importance’. dewey offers a new theory of art and the aesthetic experience which is called ‘pragmatist aesthetics’ based on pragmatist philosophy. dewey ( ) argued that ‘an aesthetic experience is awareness of an impression not only commencing by seeing a work of art’. he proposes that ‘there is continuity between the refined experience of works of art and everyday activities and events, and in order to understand the aesthetic one must begin with the events and scenes of daily life. we must recover the continuity of aesthetic experience with the normal processes of living. it is the duty of the theorist to make this connection and its implications clear. if art were understood differently by the public, art would gain in public esteem and have wider appeal.’ dewey’s pragmatist aesthetics has been cited very often and has been adapted among design theorists like schön, lundequist and buchanan who combined the pragmatist theory of dewey with design theoretical explorations (buchanan and margolin , Östman, ). part | literature study on organizational aesthetics | aesthetics dewey put much emphasis on the reflection and reasoning developed from research (Östman, ). his ‘pragmatic’ perspective on aesthetics was established in the th century and has had a great influence on american thinking and society generally (ibid). the pragmatists didn’t constitute a homogeneous group or school of philosophers, or even a consistent succession of ideas, but rather a loosely knit web of american philosophers sharing the idea of thinking being closely related to action. human action, they argue, ‘is the source of reflection, which can be developed into a conceptual understanding constituting the framework for a trustworthy understanding of the world.’ the words ‘pragmatism’ or ‘pragmatic’ might need some precautionary explanations. pragmatism originates from peirce and denotes the idea of real world experiences as the foundation of our understanding, in contrast to the idea of given natural laws (Östman, ). such a definition, Östman argues, ‘is not what we normally understand with the word: according to the oxford english dictionary ( ), to be pragmatic (adjective) is to be” matter-of-fact; dealing with matters with regard to their practical requirements orconsequences”.’ continuing with aesthetic experiences. an aesthetic experience cannot be sharply marked off from other experiences, but in an aesthetic experience, structure may be immediately felt and recognized, there is completeness and unity and necessarily emotion. ‘emotion is the moving and cementing force’, cooper et al. argue (cooper et al., ). pepper ( ) speaks about an ‘aesthetic event’ existing of the following three steps: ) the given event (knowing aspect; analysis (centrifugal) by intuition (centripetal), complementary and opposite, together they are fused); ) the physical conditions underlying the given event (they are the kind of perceptions that initiate a study of the physical conditions; the physical organism (you) is a personal texture, the object is an impersonal texture: the texture of your perception of the object is a personal- impersonal texture) and ) the individual object of which the given event is usually only a partial revelation (relationship quality: commonly known as a similarity or commonly known as individuality). stolnitz (cited by mitias, ) offers the following definition: ‘the aesthetic experience is the experience one has when the aesthetic attitude is sustained’. this definition is unsatisfying because it makes the experience depend on first having the attitude (mitias, ). mitias, who has spend his life with unraveling the aesthetic experience problem, defined this experience by saying that ´an aesthetic experience is a psychological event which take place when one perceives a work of art () at a certain time, in a certain place, and in relation to the unity of a certain object ´. ‘this unity belongs to the art work, and which makes up the structured unity of the aesthetic experience is usually indeterminate’, mitias argues. ´the principle of the unity of aesthetic experience is the complex of aesthetic qualities which the artist has created in the artistic process and embodied in the art work as a significant form´ (also called schematic formation by kant, hegel, beardsley and osborne). and mitias continues about the features of the aesthetic experience: ‘the experience is aesthetic in as much as it is pleasurable, enjoyable and meaningful’ (mitias, ). ‘the aesthetic experience is a pleasurable absorption (or contemplation) in the perceptual aspects of phenomena’ (hospers cited mead). ‘the aesthetic experience is the experience one has when the aesthetic attitude is sustained’ (hospers, ). ‘a person is having an aesthetic experience during a particular stretch of time if and only if the greater part of his mental activity during that time is united and made pleasurable by being tied to the form and qualities of a sensuously presented of imaginatively intended object on which his primary attention in concentrated’ (beardsley, ). hospers (cited by mitias, ) agrees with beardsley’s view adds two more features: ) the experience should be coherent; it should hang together; ) the experience should be complete in itself; the pleasure or emotional intensity it occasions depends exclusively on the internal structure and elements of the given art work. part | literature study on organizational aesthetics | aesthetics for csikszentmihalyi ( ) one definition of aesthetic experiences isn’t sufficient. and he distinguished four types of aesthetic experiences: cognitive, perceptual, emotional and transcendental. leading to ) the intellectual response which focused on theoretical and art historical questions; ) the perceptual response which concentrated on the elements such as balance, form, and harmony; ) the emotional response which emphasized reactions to the emotional contact of the work and personal associations and ) the communicative response wherein there was a desire to relate to the artist, or to his or her time or culture, through the mediation of the work of art. leder et al. ( ) who developed a well known aesthetic experience process defined an aesthetic experience as a ‘cognitive process accompanied by continuously upgrading affective states that vice versa are appraised, resulting in an (aesthetic) emotion.’ for parker ( ) an aesthetic experience is a synonym of beauty, which contains ) the sensations which are the media of expression and this material ) are attached vague feelings, ) represent things, ) are associated to the sense elements and constitute their meaning, ) stimulate sentiments of respect and veneration and finally ) it consists of images from the various sense departments—- sight, hearing, taste, smell, temperature, movement—which arise in connection with the ideas or meanings, making them concrete and full. scruton ( ) mainly arguing about beauty, proposed that an aesthetic experiences must be meaningful. ‘work of arts are meaningful – they are not just interesting forms in which we take an unexplained delight. they are acts of communication, which presents us with a meaning (by representation and expression, scruton cited croce and collingwood); and this meaning must be understood. it can be meaningful without being beautiful; but to be beautiful is must be meaningful. a work of art is ‘polysemous’, developing its meaning on several levels – the levels of image, of statement, of metaphor, of allegory and so on.’ so, capturing an aesthetic experience seems to be difficult. gagliardi ( ) construed this by giving the next example. ‘whether we ask corporate actors to tell us of their aesthetic experiences, or whether it is we ourselves as researchers who are interpret them, we will always dealing with ‘epoused’ theories which not in any way coincide with the secret regularities of expressive action.’ hospers ( ) noticed that the whole concept of aesthetic experience is confused, muddy, and perhaps untenable: it is extremely difficult , if not impossible, to speak of aesthetic experiences as a unique type of experience, as an experience distinguishable from moral, religious, intellectual, or sexual experience (mitias, ) reflecting on most important contributions of aesthetic experiences, there seems to be a general opinion that aesthetic experiences are perceived during a sensory, cognitive, affective, interactive and valuation process observing or even communicating with an object or event which leads to a pleasurable, enjoyable and meaningful state of mind. aesthetic experiences are concepts that are difficult to explain. for that reason the aim cannot purely be to explain the concept but to give examples of it, in order to share and improve the readers’ and users’ understanding of these aspects of design. part | literature study on organizational aesthetics | aesthetics the perceiver perceiving aesthetic value of art requires several features of the perceiver. starting with kant again, being passive although having aesthetic attention revert to the by kant earlier introduced phenomenon of disinterestedness which plays a major role in kant's discussion of the subjective universality of the judgment of taste. for kant, an interesse means ‘a kind of pleasure that is not connected with desire, neither grounded in desire, nor does it produce it. so, beauty judgment is disinterestedness, without understanding, practical purpose and without a predefined need for pleasure’, he argued. kant claims that (a) pleasure in the beautiful is disinterested, and (b) only pleasure in the beautiful is disinterested. and this plays a large role in kant's project. kant connects disinterestedness with the claim to universal validity of the judgment of taste. distinguishing kant's ambitious thesis, only pleasure in the beautiful is disinterested from his less ambitious claim simply that pleasure in the beautiful is disinterested for it seems that there could be other disinterested pleasures. the less ambitious claim, however, is certainly controversial enough (cooper et al, ). ‘the more uncontroversial component of that less ambitious claim is that pleasure in the beautiful is not grounded in the satisfaction of desire. it is plausible, that when we take pleasure in something we find beautiful, we are not pleased that we have got something that we desire’. moreover, ‘kant wants pleasure in the beautiful to be open to all (so there should be no ´aesthetic luck´, and if desire varied from to person, it seems that we could not require that pleasure from everyone, as the idea of universal validity requires. hence the claim to universal validity would be lost if pleasure in beauty were not disinterested in the sense of not being based on desire’ (cooper et al, ). however, it is not so clear that pleasure in the beautiful cannot produce desire, which kant requires for disinterestedness. the issue here is whether it can produce desire from itself. kant admits that we have certain general concerns with beauty that mean that desire may follow from a judgment of beauty; but, according to kant, such desires do not have their source solely in the pleasure in the beautiful (cooper et al, ). beardsley ( ) distinguished five recurring themes, suggesting that any aesthetic experience must exhibit the first one and at least three of the remaining four criteria: ) object focus: the person willingly invests attention in a visual stimulus (object directedness); ) felt freedom: he or she feels a sense of harmony that preempts everyday concerns and is experienced as freedom; ) detached effect: the experience is not taken literally, so that the aesthetic presentation of a disaster might move the viewer to reflection but not to panic; ) active discovery: the person becomes cognitively involved in the challenges presented by the stimulus and derives a sense of exhilaration from the involvement and ) wholeness: a sense of integration follows from the experience, giving the person a feeling of self-acceptance and self-expansion. osborne ( ) distinguishes detachment (aesthetic interest and involvement), expressiveness (emotional), unicity, imagination (holistic, empathic and synthetic) and pleasure as the most important features of the perceiver. ‘at times the perceiver’s role is overt and active, moving about in particular ways in relation to the art object and even manipulating in directly. at other times the perceiver engages the object in more subtle ways, form working with a trained awareness that can activate such things as color, linear, auditory, and spatial relationships, to supplying meanings and associations that form the aura of consciousness that surrounds the work’, stated berleant ( ). dziemidok ( ) cited shopenhauer and noticed that ‘a perceiver must be able to experience contemplation, aesthetic enjoyment and must have an aesthetic attitude’ (zemach, ; mitias, ). dziemidok elaborated the aesthetic attitude into four approaches namely: ) necessary and possible; ) necessary and possible and separate from other experiences; ) necessary, but reject the existence of a uniform and universal aesthetic attitude and ) no separate aesthetic attitude. part | literature study on organizational aesthetics | aesthetics for experiencing aesthetics, dziemidok ( ) suggests the perceiver should have an aesthetic attitude based on two conceptions: the conception of disinterestedness and the conception of contemplation. the conception of disinterestedness was earlier mentioned by kant by introducing the term ´dependent beauty´. dziemidok argues that ) the satisfaction independent of the conviction as to whether the object exist or not; ) the satisfaction without the desire to possess and ) the satisfaction without personal motivations. this last conception has been criticized by beardsley ( ) and dickie ( ; he speaks of a ‘myth of aesthetic attitude’) by arguing that the perceiver needs to have an aesthetic point of view, an aesthetic interest and readiness for a direct interest in the look. finally the perceiver ‘should have a psychical distance for being objective (for judgment) and a degree of distance: maximal distance is not a good condition for the aesthetic experience and optimal distance is the distance is smallest but still present’ (beardsley, ). ginsberg ( ) defined interest or attention as the most significant feature for perceiving aesthetics. ‘we are aesthetic beings wandering about aimlessly or busily occupied with practical matters. we have forgotten what the extraterrestrian is aware of, what we surprise ourselves with the happening of the aesthetic’. mitias ( ) claims two conditions for having aesthetic experiences: ) having aesthetic attitude; ) able to construct, apprehend, the aesthetic qualities which are potential in the given work as a significant form. he presumes aesthetic perception is not a passive process in which certain impressions of representations are automatically imprinted on the mind. in it the mind actively contemplates and responds to its object (sense-perception) and derives from is an idea, a meaning, or some kind of satisfaction. the perceived quality ‘exist’ in the work as a complex of potentialities awaiting realization qua meaning in aesthetic perception. so perception (sensuous attention, ‘i form a percept of it’) is a necessary condition for the being and knowledge of any concrete object whatsoever, mitias argued. mitias also suggested that contemplation forms a species of awareness. ‘it designates an active mental state which can be characterized only in and through anyone, or a combination, of various species: perception, sensation, contemplation, or intellectual cognition’. dziemidok ( ) agrees with mitias and offers the features of conception of contemplation. this will be accomplished by: ) completely passive and inactive perception of an object; ) direct observation; ) passionless perception and ) longer and complete focusing on one’s attention on the object csikszentmihalyi ( ) used beardsley’s five themes in his research on ‘the seeing of art’ and completed these with auto telic nature: ‘the experience does not need external rewards (no ‘ego boundaries’), but only intrinsically satisfaction and personal meaning’. girod et al. ( , p ) talks about aesthetic understanding: a rich network of conceptual knowledge combined with a deep appreciation for the beauty and power of ideas that literally transform one’s experiences and perceptions of the world. aesthetic understanding is thereafter ‘transformative (action and reflection, doing and undergoing), unifying (wholeness: deeper meaning, value on its own account), compelling and dramatic’ (ibid). leder et al. ( ), who are citing girod et al., complete these features with the input of their model of aesthetic experience, which are the characteristics of the perceiver. these are his emotional and affective state, his previous experience(s), his domain specific expertise, declarative knowledge, interest and personal state. leder et al. also emphasize the competence of self-reinforcing during the aesthetic process as important. part | literature study on organizational aesthetics | aesthetics reber et al. ( ) enumerate some personal characteristics for having aesthetic experiences, like aesthetic sensitivity, attentiveness, curiosity, intrinsic motivation, anticipation of (self)reward and aesthetic interest and taste the main characteristics. ingarden ( ) recently offers several features like cultural background and tradition, social economical status, education, individual preferences, expectations, imagination, temperament, influence of parents and peers and so forth. they complete the indeterminacies and constitute the aesthetic qualities in ways that also exhibit significant differences according to scruton ( ), referring to kant, disinterested is to be interested (in beauty) is to set all interest aside, so as to attend to the thing itself. ‘a perceiver is not motivated by self-interest or by any interest other than the interest in doing just this, namely helping their neighbors. they have disinterest interest’. in sum, experiencing aesthetics requires an aesthetic attitude and interest of the viewer or at least attention for it. and being attended by ‘something beautiful’ the ability to apprehend and understand the several aesthetic properties of the object or event, keeping ingarden’s mentioned features of the viewer in mind like cultural background and tradition, social economical status, and education. thus, reflecting on these contributions on the role of the perceiver, observing aesthetic value of art requires several features of the perceiver. most contributors agree with kant’s thesis that interest means a kind of pleasure that is not connected with desire(aesthetic interest and involvement), but this interest is caused by stimuli (´being attended’) which arouses observers cognition, expressiveness (emotional), identity and imagination (holistic, empathic and synthetic). part | literature study on organizational aesthetics | aesthetics . aesthetic quality and properties the objectivism view (based on plato) claims that an object has qualities or properties that produce (purportedly) a pleasurable and/or valuable experience in any perceiver. the supporters of this perspective (like acquinas, birkhoff, gombrich, arnheim) attempt to identity critical contributors to an aesthetic experience like balance and proportion, symmetry informational content and complexity, contrast en clarity. the objectivism view investigates the properties and qualities of the object. ‘aesthetic properties have an inherent evaluative polarity and are mind-independent’ (goldman, ). for unraveling the aesthetic qualities and properties of objects, objectivists speak about the ‘ontology of aesthetics’. there have been several classifications defined. ´plato, the first philosopher of art, and later aristotle, identified beauty with simplicity, harmony, and proportion (cooper et al. ). unity in variety was long thought to be the same as beauty; and, ‘although this view is obviously one-sided, no one has since succeeded in persuading men that an object can be beautiful without unity’. (ibid) pepper ( ) talks about the ‘intensification of quality’. he focuses on the novelty (‘naïve or intrinsic: uniqueness: the name that we give either to the naïve quality of events, or to that factor which breaks up habit and monotony; novelty, if not naively present, is the tearing of habit’) of the art work. according to pepper, ‘the emphasis is aesthetics must be on the vividness of the quality, not on its uniqueness, and this is not because the uniqueness is unimportant, but only because it can always be relied upon whereas the vividness cannot’. beardsley ( ) who first challenged the subjectivist view started a long debate by drawing up the next hypothesis. ‘the degree of complexity, intensity and unity of the aesthetic experience though directly related to the complexity, intensity and unity of the aesthetic object on which it is directed, is not reducible to them: it is a feature of the experience itself. the aesthetic value of aesthetic objects then lies in their capacity to produce experiences of this kind, and these experiences crate in turn valuable in various ways for those who have them.’ beardsley drew up the hypothesis that ‘we can distinguish an aesthetic experience from an non- aesthetic one in terms of its own internal properties, and thus decide whether or not an experience is aesthetic without having first to know whether an object or (and in) the experience has the properties that permit aesthetic experience’. so, what are aesthetic properties or qualities? although aesthetic qualities as the term is commonly understood – qualities such as gracefulness, elegance, daintiness - are emergent, but not all emergent properties are aesthetic qualities. ‘aesthetic qualities are distinctive in that the constituent parts of the wholes which they qualify remain perceptible simultaneously with them’ (osborne, ). an artifact is a work of art in as much as it possesses aesthetic qualities and is therefore the ground of an aesthetic experience (zemach, ; beardsley, ). dickie ( ) mainly criticizes beardsley’s transfer of the terms complexity, intensity and unity from the objects of aesthetic experience itself. he grants that ‘aesthetic objects can be coherent and complete, for example, and that we can experience their coherence and completeness. we confuse an experience of completeness with the completeness of an experience’, he said. beardsley suggests (attended to zangwill, ; goldman, ) that ‘all aesthetic qualities are intimately connected to normative critical judgments’ (bender, ). nevertheless, beardsley attained many supporters of his objectivism view. osborne ( ) argues that a work of art contains sorts of qualities causing feelings and moods. they can be divided into ) descriptive qualities (a. emergent qualities like elegance, gracefulness, prettiness); b. ‘formal’ qualities like regularity, balance, rhythm; c. ‘aspect’ qualities (like dignified, part | literature study on organizational aesthetics | aesthetics solemn, sedate, pompous ), ) evocative or affective qualities (moving, charming, nice, disguising) and ) expressive qualities (sad, joyful, gay, serene). these have some similarity with the five types of qualities hermeren ( ) distinguishes : ) emotion qualities (‘sad’), ) behavior qualities (‘restrained’), ) gestalt qualities (‘unified’), ) taste qualities (‘garish’, ‘beautiful’) and ) reaction qualities (‘moving’). ‘a form is purposive inasmuch as it is capable of realizing a meaningful, life-enhancing experience’, mitias ( ) started about arguing aesthetic features of an object. according to mitias, ‘an experience becomes aesthetic when the aesthetic feature of the object infects (‘an aesthetic object is the art work perceived aesthetically when people actualizes in his experience the fullness of its aesthetic properties) or is ingressed, in the experience’. therefore the object must have: ) intrinsic qualities like brightness or vivacity; ) formal qualities: the fabric which gives it structure must likewise be living, or capable to live. its ‘logic’ organizes the material of the artistic process into a unified whole. so the content lived – hope, anxiety, fear, harmony, tension, order, beauty, etc. - becomes valuable, and the skillfully embodies it in a sensuous form. the organic unity of the world lived is in principle transferred to the physical work as living form. this organic unity forms the fundamental structure expressive of the aesthetic value. according to mitias ( ), ‘this is not a physical or mental reality; it is the meaning enjoyed in the perception of certain qualities in the work of art as a given object. and the unity of the aesthetic experience is the counterpart of the unity of the art object’, mitias argued. ‘its construction is determined by the sensuous form as a possibility of realizing aesthetic experience features of the form of the art work’ which are : ) a careful comparison between two or more art forms (comedy, tragedy, or concerto and a sonata) and ) knowledge of the formal structure. ‘form is, accordingly, the being. or substance, of the art work. the work qua art does not have form; it is a form, and reveals itself as form.’ form is the unity of the sensuous content of the work as a meaningful whole’, he stated. ‘the whole is said to be organic (unity in diversity) when its parts are interrelated. the character of the whole is determined by the way the parts interact; each part is determined by the details which environ it, but it also influences the quality and role which the parts play in the life of the whole’. sandelands and buckner ( ) distinguishes three so called ‘boundaries’ which should be part of an object of art: dynamic tension, record of growth and unresolved possibility. goldman ( ) goes further and offers the following eight categories: pure value properties (‘beautiful’), emotion properties (‘sad’), formal properties (‘balanced’), behavioral properties (‘daring’), evocative properties (‘stirring’), representational ´properties´(‘realistic’), second-order perceptual properties (‘vivid’) and historical related properties (‘original’). zemach ( ) distinguishes primary properties (‘properties of noumena; things whose existence is not perceiver-dependent’), secondary properties (‘properties of phenomena; appearances of real things to minds’), tertiary properties (‘properties of significant phenomena; phenomena mediated by interest’).these classification diverged from the most used ontological parts of aesthetic quality zemach construes beauty besides harmony, power, significance, tension and their opposites as general properties), because zemach adds the aspect of desire. zemach offers a second classification by distinguishing two types of value of a theory: internal value properties (simple, rich, elegant and unity in variety) and external aesthetic value (harmoniously and gracefully integrates with other theories). about how people perceive aesthetic properties, zemach argues: ‘aesthetic properties ontologically depend on human beings and cannot exist without them; they emerge only when we perceive things via interest-filtered sensitivity when desire perceptually and directly informs us about ambient things. part | literature study on organizational aesthetics | aesthetics therefore it seems that noumena cannot have aesthetic properties. if aesthetic properties reflect the value that we put on things, the no aesthetic (tertiary) properties can be primary properties too’. he arrays his proposition with a example. ‘when a real thing x impacts on a perceptual system, the latter presents x’s primary properties as modulated and modified by the system’s specific nature. the result is a phenomenal object having secondary properties: x’s properties as rendered by the system. a tertiary property results when yet another mental system further modulates a secondary property. that additional system is, i say, desire. aesthetic properties perceptibly present the desirability of things ingrained in those things themselves. we perceive x as having an aesthetic property a only if we perceive it, so to speak, conatively. an aesthetic object is, then, a desire-mediated phenomenon’, according to zemach. wagner ( ) assumes that all aesthetic properties are perceptual. she distinguishes two categories of properties: local and regional. the local properties are the elements of a design. the regional properties can be divided into structural (part of the design principles, ´they are used to organize the local properties into a pleasant visual image) and emergent properties´. without mentioning it, these structural properties can be considered as formal properties distinguished by osborne ( ), goldman ( ), leyton and ramachandran ( ) and parker ( ). they are interrelated, according to wagner. ´they supervene. beauty of form emerges from perceived unity and harmony; beauty of expression emerges from variety such as contract in color, light or line. the latter holds the attention of the perceiver and makes the aesthetic object more interesting´, she claims. leyton and ramachandran ( ) came up with eight laws for evaluating artwork which they called the very first experiments ever designed to empirically investigate the question of how the brain respond to art. they start their famous article with three components of art theory: (a) the logic of art: whether there are universal rules or principles; (b) the evolutionary rationale: why did these rules evolve and why do they have the form that they do; (c) what is the brain circuitry involved? and agreed with the hypothesis that ‘beauty is in the eye of the beholder’ but wonder if there might be a sort of universal rule or ‘deep structure’ underlying all artistic experiences. they developed eight of these rules: . the peak shift principle; not only along the form dimension, but also along more abstract dimensions, such as feminine/masculine posture, color (e.g. skin tones) etc. furthermore, just as the gull chick responds especially well to a super beak that doesn’t resemble a real beak, there may be classes of stimuli that optimally excite neurons that encode form primitives in the brain, even though it may not be immediately obvious to us what these primitives are. . isolating a single cue helps the organism allocate attention to the output of a single module thereby allowing it to more effectively ‘enjoy’ the peak shift along the dimensions represented in that module. . perceptual grouping to delineate figure and ground may be enjoyable in its own right, since it allows the organism to discover objects in noisy environments. principles such as figure– ground delineation, closure and grouping by similarity may lead to a direct aesthetic response because the modules may send their output to the limbic system even before the relevant objects has been completely identified. . just as grouping or binding is directly reinforcing (even before the complete object is recognized), the extraction of contrast is also reinforcing, since regions of contrast are usually information-rich regions that deserve allocation of attention. camouflage, in nature, relies partly on this principle. . perceptual ‘problem solving’ is also reinforcing. hence a puzzle picture (or one in which meaning is implied rather than explicit) may paradoxically be more alluring than one in which the message is obvious. there appears to be an element of ‘peekaboo’ in some types of art — part | literature study on organizational aesthetics | aesthetics thereby ensuring that the visual system ‘struggles’ for a solution and does not give up too easily. for the same reason, a model whose hips and breasts are about to be revealed is more provocative than one who is completely naked. . an abhorrence of unique vantage points. the visual system rejects the interpretation which seems not to be logic or being highly improbable. . perhaps most enigmatic is the use of visual ‘puns’ or metaphors in art. in art, the term allegory is often used. which is a symbolic representation with an idea or abstract concept (e.g. virtues and vices) is represented by one or more personifications, individuals and specific issue. such visual metaphors are probably effective because discovering hidden similarities between superficially dissimilar entities is an essential part of all visual pattern recognition and it would thus make sense that each time such a link is made, a signal is sent to the limbic system. . symmetry, whose relevance to detecting prey, predator or healthy mates is obvious. comparing these principles with the several types of aesthetic properties, it can be conclude that all these principles are part of formal or gestalt properties like earlier for example mitias ( ), zemach ( ) and goldman ( ) argued. leyton ( ) earlier wrote a massive book about symmetry, causality and mind and proposes several principles related to the earlier mentioned formal properties, especially for paintings. the principles possibly later related to work and organizations are: ) the more symmetric a configuration is, the more stable it is to understood; ) an art-work is the process-history inferred from it; ) the experience of an art-work is the experience of interring that history, i.e. the experience of solving its history- recovery problem; ) each individual has a preferred level of environmental complexity, a level that the individual seeks, and finds extremely appetitive ; ) these is a primary drive to seek causal explanation; i.e. a drive independent of, and not subservient to, any other goal; ) each individual has a preferred amount of environmental asymmetry, an amount that the individual seeks, and finds extremely appetitive. both carroll ( ) and levinson (unpublished) emphasize the importance of attending to form/formal properties to conduce aesthetic experience. they both seem to suggest that formal properties are observable and perceptible parts of an artwork. both endorse for traditional formalists´ opinion that ‘conducing aesthetic experience requires one attend the formal properties of an artwork with disinterestedness’ (freeman, ). carroll claims that ‘one must realize what the artist is trying to say, while discerning how the formal properties succeed or fail in realizing this.’ he calls this “design appreciation” and states that, ‘if our experience is preoccupied with discovering the structure of the work – that is aesthetic experience’. according to carroll, ‘that in discovering the structure of the work and conducing aesthetic experience one discovers aesthetic properties. these properties are concepts such as grace, beauty, and unity, which the artist intends to express’. for carroll, an aesthetic experience is no more than an adequate attention of formal properties in order to discover these aesthetic properties (kamram achmed, ). alternatively, jerrold levinson suggests that the difference between aesthetic experience and non- aesthetic experience is not in what one attends to (the formal properties themselves), but the way one attends to these properties. while carroll supposes that ‘aesthetic experience is realized when one adequately attends to the formal properties of an artwork’. levinson, who argued that ‘carroll misses the fact that aesthetic experience is somehow rewarding, valuable, and worthwhile, supposes that an aesthetic frame of mind is necessary’. he claims that, ‘even with adequate attention to formal details, one cannot realize aesthetic experience unless one attends these properties in the right manner for valuing and appreciating the experience. he believes that attention to these properties with an aesthetic state of mind suffices for triggering aesthetic experience. then, once in that state of mind, further attention of formal properties help in maintaining and developing aesthetic experience. part | literature study on organizational aesthetics | aesthetics levinson agrees that formal properties are important in conducing aesthetic experience from artworks; however, how one attends these properties is fundamental’ (ibid). zangwill ( ) and (locke, ) offer to types of an aesthetic property: primary qualities (shape, size) and secondary qualities or called sensory properties (color, sounds, tastes, smells). parker ( ) is quite clear about the role of formal properties: ‘for structure has, oftentimes, a direct emotional appeal, which has not yet been taken into account, and which is a leading motive for its presence’. consider, for example, symmetry, he continued. ‘a symmetrical disposition of parts is indeed favorable to perspicuity; for it is easier to find on either side what we have already found on the other, the sight of one side preparing us for the sight of the other; and such an arrangement is flattering to our craving for unity, for we rejoice seeing the same pattern expressed in the two parts; yet the experience of symmetry is richer still: it includes an agreeable feeling of balance, steadfastness, stability.’ ‘structure is not a purely intellectual or perceptive affair; it is also motor and organic, and that means emotional. it is felt with the body as well as understood by the mind’, parker noted. parker ( ) distinguishes three qualities ´of which each one may include important special forms´: ) unity in variety, ) dominance and ) equilibrium. unity in variety was the earliest of the types to be observed and is the most fundamental. ‘it is the organic unity so often referred to in criticism. it involves, in the first place, wholeness or individuality’. he divided unity in variety divided in three modes: - the harmony or union of cooperating elements; - the balance of contrasting or conflicting elements (proportion); - the development or evolution of a process towards an end or climax (the process or sequence in which all the elements, one after another, contribute towards the bringing about of some end or result). ‘in an aesthetic whole the elements are seldom all on a level; some are superior, others subordinate. the dominant elements are not only superior in significance; they are, in addition, representative of the whole; in them, its value is concentrated; they are the key by means of which its structure can be understood. in an aesthetic whole there are certain qualities and positions which, because of their claim upon the attention, tend to make dominant any elements which possess them’. equilibrium or impartiality is a principle counteracting dominance. ‘it demands, despite the subordination among the elements, that none should be neglected. each, no matter how minor its part in the whole, must have some unique value of its own, must be an end as well as a means. the individuality of the elements must not be so great that we rest in them severally, caring little or nothing for their relations to one another and to the whole. the contribution of this principle is richness. unity in variety gives wholeness; dominance, order; equilibrium, wealth, interest, vitality’. (parker, ) scruton ( ) noticed the role of features of art (‘those universals’) and stated that ‘symmetry and order; proportion; closure, convention; harmony, and also novelty and excitement: all these items seem to have a permanent hold on the human psyche’. he also named style as a distinctive feature of art: ’through style we grasp what is being emphasized, what placed in ten background, and what being connected with that. hence style is one of the features of everyday aesthetic judgment that we carry over into art, where it takes on a wholly significance (scruton, ). ingarden ( ) examined the aesthetic qualities of literary work of art (‘strata’) and distinguished several properties of this art form. these are word sounds (phonic form), meaning (ontological ground of the literary work), represented objects (things, places, events, situations, state of affairs), objective properties (linguistic structure), symbols and aesthetic qualities (beautiful, grotesque, sublime, graceful, holy). part | literature study on organizational aesthetics | aesthetics people are having aesthetic experiences because of the (degree of) recognition or attribution of aesthetic qualities or properties in the object or artifact they observe. literature distinguishes many types of aesthetic qualities. these aesthetic qualities or properties show some similarities and differences. the distinguished aesthetic qualities or properties can be ordered by gradation (objective to subjective). reflecting on above cited aesthetic qualities or properties a tripartition of formal, representational and expressive aesthetic properties these can be made, following goldman’s and wagner categories. leyton and ramachandran’s list of formal properties is full- featured and validated and has been used in the field research of this project. many respondents have recognized and confirmed these formal properties. formal (non-evaluative, objective, metaphysical) representational / symbolic expressive and transcendental (evaluative, subjective) plato aristotle van aquino kant simplicity harmony proportion clarity wholeness beardsley complexity intensity unity zangwill primary qualities (shape, size) secondary qualities (color, sounds, tastes, smells) locke primary qualities (number, solidity, motion, shape. size) secondary qualities (color, sounds, tastes, smells) zemach primary properties (unity, coherence, balance, harmony, power, significance, tension) secondary properties (sweet, scented, hot, loud, soft, red) tertiary properties (contextual like original, conservative, radical, liberating, stifling, antiquated, quaint, fashionable, daring, provocative, flowery, terse, vulgar, stylish, rude, polite, candid, arty, romantic, exotic, commonplace, primitive ) osborne ‘formal’ qualities (regularity, balance, rhythm) emergent qualities (elegance, gracefulness, prettiness) ‘aspect’ qualities (dignified, solemn, sedate, pompous evocative or affective qualities (moving, charming, nice, disguising) expressive qualities (sad, joyful, gay, serene). goldman formal properties (‘balanced’) representational properties (‘realistic’) historical related properties (‘original’) behavioral properties (‘daring’) second-order perceptual properties (‘vivid’) value properties (‘beautiful’) emotion properties (‘sad’) evocative properties (‘stirring’) wagner non-evaluative regional structural evaluative non-evaluative regional emergent leyton and ramachandran peak shift isolation (simplicity, ‘less is more’) grouping contrast perceptual problem solving symmetry abhorrence of coincidence / generic viewpoint repetition, rhythm and metaphor part | literature study on organizational aesthetics | aesthetics formal (non-evaluative, objective, metaphysical) representational / symbolic expressive and transcendental (evaluative, subjective) orderliness balance metaphor parker unity in variety dominance equilibrium or impartiality table . overview of aesthetic formal properties citing sibley (in cooper et al., ): ‘aesthetic properties are those that require taste to be perceived’ could suggest that only evaluative properties of an object or artifact, the representational properties, seems to do a claim on taste of people. thus, it is purer to maintain the before mentioned object- subject interaction. it could be argued that the distance between object and subject 'bridged' by the recognition of (observable) formal properties of the object, the recognition of expressive properties of the object that eventually followed by the attribute (subjectively) of representational properties by and in the viewer. because of this difference in distance between object and subject, it is incorrect to speak about representational 'properties'. it does not concern an objective quality of the object, but an attributed one by the observer. representational properties are attributed to what one perceives. with this caveat, nevertheless the term is used in this study, but with the use of quotation marks. wagner ( ) states that ‘formal properties are the principles of design, which enable perception and cognition of the visual image. expressive properties are associations the subject makes with previous objects and experiences, engaging the memory, imagination and affective capacity. they create value in the form of ‘distinct worlds’. she joins goldman’s ( ) opinion that aesthetic properties can be divided into two categories: non-evaluative properties (formal properties and expressive properties) and evaluative properties (pure properties like beauty and elegance, evocative properties like power or amusement and emotive properties like joy and delight). ‘the evaluative aesthetic properties supervene on the non-evaluative aesthetic properties’, she claims. cooper et al. ( ) suggested that evaluative (descriptive) and relational properties are express some set of aesthetic values. this phenomenon asks for more plausible general criterion (non-evaluative or objective) for identifying aesthetic properties. he argued that ‘the formal properties help to determine expressive behavioral and representational qualities, which may in turn enter formal structures at higher levels, and so on. since elements within works are grasped in terms of their contributions to aesthetic properties and to such complex interactions among them, this makes for an intensively meaningful and rich experience of these elements as they are perceived’ (ibid). parker ( ) agrees with this opinion by arguing that ‘structure is not a purely intellectual or perceptive affair; it is also motor and organic, and that means emotional. it is felt with the body as well as understood by the mind’ according to parker. for structure, he refers to the formalistic properties of art.’ oftentimes, a direct emotional appeal, which has not yet been taken into account, and which is a leading motive for its presence. consider, for example, symmetry. parker argues that ‘a symmetrical disposition of parts is indeed favorable to perspicuity; for it is easier to find on either side what we have already found on the other, the sight of one side preparing us for the sight of the other; and such an arrangement is flattering to our craving for unity, for we rejoice seeing the same pattern expressed in the two parts; yet the experience of symmetry is richer still: it includes an agreeable feeling of balance, steadfastness, stability’. like dewey ( ) many years ago stated: ‘to restore the union of sense (unitary perception), need, impulse and action characteristic of the live creature’. part | literature study on organizational aesthetics | aesthetics aesthetic properties in other art forms aesthetics mainly examines art objects like paintings, architecture and sculpture. objects which are contemplated and sometime s admired after the artist has finished his art work. aesthetic experiences and quality in relation to living objects - their performance forms the art - like dance or theater are much less described. in this case of thinking about aesthetics in organizations, dominated by human artifacts, possibly these two art forms could be challenging aesthetics in organizations. dance and theatre ‘dance qua art, is essentially a form of representation, where ‘representations’ is understood primarily as imitation, the process of referring to actions, events, and people by stimulating their appearances’ (carroll, ). levinson ( ) advocates that ‘a position on the aesthetic nature of dance that is close in many respects to the sort of formalism that bell advocated with respect to the visual arts, that is, that something truly dance only if it possess perceptible choreographic form’. like formalism, is arises in reaction to the imitation theory of dance: the expression of feelings, particular emotions (carroll, ). smith-autard ( ) mentioned in her practical guide for teachers of dance eight so called elements of construction of a dance: the motif (foundation of construction), repetition, variation and contrast, climax or highlights, proportion and balance, transition, logical development and unity (the overall constructional element) which can be achieved by employing the seven mentioned elements (formal properties). according to smith-autard, ‘the motif or foundation of construction only emerge as dominant in the light of all other constructional devices used. here, implicitly she refers to the theory of the aesthetic properties supervene on the non-aesthetic properties. she stated: ‘without repetition, the motifs would be forgotten; without variation and contrast, repetition of the motifs would be dull if presented ad lib in their original form; a dance lacking climax or highlights would seem to have motifs which have no content worth highlighting; without careful proportioning and balancing of the whole work each of the motifs could become almost eliminated or even too dominant; without transitions the motifs would be isolated movement statements. transitions between each movement within the motif and between the motifs are important in defining the phrase and section shaping of the dance; without logical; development from motif to motif, the theme of the dance would be blurred and finally, the motifs contains the main ingredients which provide the unifying threads for the whole work. these include style, qualitative color, light and shade, line and shape in space, and types of action which motivate the rest of the work’. wages and hornung ( ) distinguish symmetry / asymmetry, perspective / vanishing points, proportion, contrast, rhythm and harmony as aesthetic dramaturgic properties. literature although literature can be considered as an art form, aesthetic properties are less easy to distinguish. these ´invisible´ aesthetic properties like harmony, unity or history are hided in the sentences itself. a form like a sonnet. dawkins ( ) points to the application of the social identity theory in literature. this theory assumes ‘that people divide the world into categories to make it more understandable’. rancour-lafierre ( ) speaks about the role of recognition and identification as an important reason why people like certain books. people like themselves identified with the characters, the emotions and the story(line) in the book. miall ( ) argues that reading should be considered as a learning activity. ‘precisely the unknown would attract people’. gerrig ( ) explains this phenomenon as ‘the need of people not only for pleasantness but also for usability of a book, as the fulfillment of dreams’’. in terms of aesthetic properties, especially the representational ´properties´ seem to resemble the part | literature study on organizational aesthetics | aesthetics aesthetic appreciation of a book. natural and environmental aesthetics aesthetics initially focused on art. but during the course in the eighteen century, philosophers like kant and writers began to turn their attention to the subject of beauty, ‘it was not art or people but nature and landscape that dominated their thinking’ (scruton, ). ‘kant refers to nature because of its perfection of form and intricate harmony of detail (others like burke admires the harmony, order and serenity of it). and he made a distinctions of ‘free’ beauty that we experience from natural objects, which comes to us without deployment of any concepts on our part, an the ‘dependent’ beauty that we experience in art, and which depends upon a prior conceptualization of the object’ (scruton, ). hepburn (cited by budd, ) distinguishes four typical aspects of natural aesthetics. first, being both in and a part of nature, our aesthetic involvement with nature is typically both as actors and spectators. second, natural things are not set apart from their environment as objects of aesthetic: they are ‘frameless’. third, the aesthetic experience of nature should not be restricted to the contemplation of uninterpreted shapes, colours, patterns and movements. and finally, budd cites, ‘there is the idea that the imaginative realization of the forces of process that are responsible for a natural thing’s appearance or are active in a natural phenomenon is a principle activity in the aesthetic experience of nature’. cooper et al. ( ) conclude that typical problems are posed for aesthetic appreciation by the very nature of environments. ‘are own surroundings are unruly and chaotic objects of appreciation and that we are plunged into them without aesthetic guidelines. if we move, we move within the object of our appreciation and thereby change our relationship to it and at the same time change the object itself. the experience of the environmental object of appreciation from which aesthetic appreciation must be fashioned is initially intimate, total and somewhat engulfing. the environmental object of appreciation does not come to us ‘framed’ as do traditional artistic objects, neither in time as a drama or a musical composition, nor is space as a painting or a sculpture. environments grow; they develop either by means of natural processes or by means of human agency, but even in the latter case only rarely are they the result, of a designer embodying a design. so, the appreciation, we speak about nature, must be fashioned anew, without the aid of frames, the guidance of designs, of the direction of designers. the perceiver himself select a the senses that are relevant to its appreciation and set the frames that limit it in time and space’, cooper et al. argue. environmental aesthetics doesn’t literally refer to the nature by kant was inspired. but environmental aesthetics mend to investigate the aesthetics of the daily human surroundings. berleant ( ; ) tried to describe ‘environmental aesthetics’. natural esthetics, according to berleant is ‘too much characterized by the detachment and passivity of a viewer who only looks at the nature and at isolated objects out of which it therefore can have no intense personal relationship’. berleant starts form art. ‘modern art has become environmental, and therefore we need an aesthetic that meet their needs into account and explaining how we can actively participate in the arts. aesthetic and ethical values seem to be in direct position in environment even more strikingly than in art. ‘an aesthetic interest in environment can help achieve moral ends. and an environment rich in positive aesthetic value not only increases feelings of well-being but reduces the incidence of physical and mental illness and of social ills, such as vandalism and crime’ (berleant, ). von bonsdorff ( ) suggests four qualities (environmental qualities’) which are typical ones for experiencing the environment. first, the by gibson introduced term ‘affordance’ refers to what an environment offers in terms of the possibilities to perform activities and fulfill needs. second, enticement, which can be understood as a kind of affordance, or as environmental promise (‘a view and opportunity for movement from one space to another whose features or only partly revealed’, von bonsdorff cited hildebrand) . third, generosity, to indicate a perceived quality of the way an environment is inhabited. and the last quality is recognizability which facilitates both the possibility of part | literature study on organizational aesthetics | aesthetics feeling at home and the use of urban space. ‘these four qualities make an environment more habitable and, as a rule, both support and are supported by processes of diversification’, according to von bonsdorff. wang, you and lee ( ) concludes that ‘environmental aesthetics since the th century has emerged from the old school of disinterested contemplation of impressed sensory images from natural landscape to a new paradigm richly emotion-charged close engagement with a cultural artifact’. ‘by recent influences of cognitive psychologists, the concept of environmental aesthetics has firmed to its initial fledged stage, which stresses an interactive understanding of one’s surroundings, and the study of environmental aesthetics has finally lived up to its more modern term of being a ‘scientific study of beauty’, which in turn gives the modern environmental aesthetics’ ethos of being ‘public serve’ and professional design’ a solid foundation to build upon’, according to wanget al. ( ). sepänaa (cited by foster, ) explores the search for a link between aesthetic assessment and the search for reliable context of appreciation. he concludes that ‘the task of environmental aesthetics in a meta-critical sense is the theoretical control of the description, interpretation and evaluation of the environment and the creation of a frame of reference. it constructs a model of how the environment is received, and in what ways it operates as an aesthetic object’. muelder eaton (cited by foster, ) suggests ‘‘good environments’, which often function as legible environments, reflections of the degree to which we can draw on non-perceptual information to form the landscape into a coherent and pattered whole’. aesthetics in daily life ‘every day aesthetics’ refers to the possibility of aesthetic experience on non-art objects en events (like a garden, cookery and present day culture), as well as to current movement within the field of philosophy of art which rejects or puts into question distinctions such as those between fine and popular art, art and craft, and aesthetic and non-aesthetic experiences (sartwell, ). dewey ( ) was the first aesthetician who claimed that a meal, or a child watching a fire engines are examples of ‘experiences that dramatically standout from what comes before and what comes after. these kind of experiences are’, according to dewey, ‘double-barreled’: ‘it refers to both to what is happening in the head and to what is happening in the world. we do not usually say that we experience our own perceptions, but rather that we experience the meal, the fire engine, and so on. experience is an interchange between world and organism’, according to dewey. berleant ( ) is another follower of the aesthetics of the everyday’. he advocates a ‘participatory aesthetics’ that connects art to every cultural practices and environmental connections (sartwell, ). considering the features of other art forms, and compare these with those aesthetic properties of ´common´ art, it can be concluded that in all art forms mentioned formal, representational and expressive properties provoke aesthetic experiences. in natural and environmental aesthetics and aesthetics in daily life, interestingly much less the discussion or even battle between the objectivist and subjective view prevail. referring to the organizational landscape in daily life, and considering the discussions during the five conducted empirical studies, respondents didn’t even worry about those different perspectives. according to words of dewey , their daily work experiences are an interchange between the organization world and the employees. part | literature study on organizational aesthetics | aesthetics . experiencing beauty than beauty. ‘everything has its beauty, but not everyone sees it’ stated confusius long ago. beauty often is part of a list of other indications for liking something, like the sublime, the comic, the grotesque, the or the picturesque. but the impact of beauty is irresistible, kant wrote. ‘it slips in and permeates our soul’. the first thoughts about beauty are expressed by plato and plotinus. plato believed that beauty is ) a kind of good; ) which can be possessed by items of any kind and ; ) which is linked with pleasure and inspires love (mothershill, ). hogarth at the beginning of the th century stated that beauty consists of ( ) fitness of the parts to some design; ( ) variety in as many ways as possible; ( ) uniformity, regularity or symmetry, ´which is only beautiful when it helps to preserve the character of fitness´; ( ) simplicity or distinctness, ´which gives pleasure not in itself, but through its enabling the eye to enjoy variety with ease´; ( ) intricacy, ´which provides employment for our active energies, leading the eye on "a wanton kind of chase"´; and ( ) quantity or magnitude, ´which draws our attention and produces admiration and awe´. mothershill subsequently cites santayana ( ) who claimed some instances about beauty: ) all values are in one sense aesthetic value is ultimately intrinsic; ) difficulty connected with definitions, like beauty, arouse anxiety about standards; if you can’t even identity the key aesthetic feature, what defense is possible against untrammeled ‘subjectivism’ or relativism’?; ) it belongs to the domain of ‘that whereof one cannot speak’, because aesthetics don’t have peculiar aesthetic predicates; ) in addition to ), practical deliberation about aesthetics, where goals and interest are shared, can get along using only minor premises.; ) the attempt to define art or beauty and with it the whole idea that there could be such a thing as a general aesthetic theory is a mistake. by value positive and intrinsic, santayana meant that ‘beauty provides pleasure without any reasoning about expected utility’. this is similar to thomas of aquinas’ definition of beauty: ‘beauty is that which it makes an object good to observe’, citing to the primary aesthetic qualities of balance and unity. ‘beauty is the glow of well-informed things that richly satisfy our cognitive desire’. it is as what gives pleasure at sight, suggesting immediate joy without intermediate reasoning did not believe that a person with real sensibility ever stands before a picture and, after a long process of analysis, pronounces himself pleased. we either like at first sight, or not at all (reber et al, ). according to pepper ( ), there are three highest grades of beauty: ) vivid in quality; ) great spread and ) depth. and ´beauty eliminates conflict, analysis, and regularity, and seeks for the maximum of harmony, pure intuition, and novelty´. pepper was one of the first aestheticians who talked about the organizations or texture of beauty (‘enhanced quality of intensity and extensity texture’). ´beauty is harmony of conflicts, without there is no vividness. ‘there is beauty without organization, but not massive beauty’, he stated. organizing beauty can be ) intrinsic: limited by human attention and human interest; function of intrinsic organization is artificially to increase these limits, the result of limitation of human attention is established by a pattern (unit attention pattern; balance, symmetry but also conflict between them), the result of limitations of human interest (design); ) extrinsic: the structural skeleton of the work, based on social interest (laws, fashions, manners) and ) intrinsic-extrinsic: extrinsic as regards the mode of organization, intrinsic as regards its embodiment in a work of art. ´an extrinsic organization a work of art participates in structures which it can never incorporate with it. in intrinsic organization the structure is created by the artist within the work and exists only in the work´, according to pepper. ‘with attention the artist builds up patterns by following and exploiting the natural tendencies for grouping, so with interest het builds up design by following and exploiting the natural tendencies for variation’, he argued. pepper distinguished three principles of variation: ) contrast (asks for relation); ) gradation (gradational climax) and theme (intrinsic modes of organization, whereas types are partly extrinsic) and variation (like repetition is minimum variation). design, pepper continued, ‘is a principle for the marshalling of these principles. you can call it restraint: it cautions an artist against filling a part | literature study on organizational aesthetics | aesthetics texture to the maximum of interest in every strand and trying to maintain that intensity of interest steadily.’ pepper explained his ideas by mentioning a musical design:’ it consists in taking a pattern, the theme, and making sure that this has been apprehended and can be recognized elsewhere and in other forms. the quality of the elements of the pattern themselves appear, the very pitch and interval or just that timbre of an instrument; an similarly with hues and shapes. so here again, an organizing principle becomes also a principle of vividness: ‘the combination of the principle of theme and variation with that contrast and the two with structure of attention, so fruitful in design that it serves a special name almost as if it were a separate design principle.’ (pepper, ) morthershill ( ) said about beauty that beauty is always ‘narrowly’ determined by ‘perceivable’ properties and it is a disposition to produce pleasure in virtue of aesthetics properties. she concludes that ‘beauty is characteristically diffusive; good in itself, it illuminates the environment and is seen to presage other different goods. but the promise it holds out is not one on which we can safely rely (this is something everyone knows but finds hard to remember). mothershill appeals to a ‘anti-theorist position’: ´contemplating beauty as a ‘peculiarly basic concept, an anomaly calls for explanation’. ‘full beauty depends upon an adaptation of the object to the senses, attention, and synthetic functions of the mind’, parker ( ) states. beauty according to parker, ‘is exclusion versus diffusion, balance, clarity, and simplicity’. and parker writes that functional unity, although necessary, is not sufficient for aesthetic unity; in addition, there must be formal unity—design, composition. parker offers two levels of beauty. first, that of appearance, of form and sensation, line and shape and color; and second, that of purpose spoken in the form. ´the form, although beautiful in itself, should reveal the function, and the decoration, no matter how charming, should be appropriate and subordinate. otherwise, as indeed so often happens, ‘the beauty of one aspect may completely dominate the others; when the object either remains a pretty ornament perhaps, but is functionally dead; or else, if it keep this life, loses its unity in a rivalry of beautiful aspects’. parker argues a failure to make the useful a part of the beautiful. ’we cannot get rid of the practical for the sake of the aesthetic, but must take up the practical into the aesthetic. ‘most buildings, it must be admitted, are not beautiful at all. in order to be beautiful, they should be alive, and alive all over, as a piece of sculpture is alive; there should be no unresponsive surfaces or details; but most of our buildings are dead—dead walls, deadlines, oblong boxes, neat and commodious, but dead’, according to parker. this interpretation of a building in terms of its purpose and history is necessary to a complete aesthetic appreciation´. let’s end with scruton who recently devoted a book on this subject. ‘beauty is an ultimate value, something that we pursue for its own sake, and for the pursuit of which no further reason need ne given’, he writes. we call something beautiful when gain pleasure from contemplating it as an individual object, for its own sake, and in its present form, he states. ‘because it is beautiful’ is a immune to counter-argument, according to scruton ( ). scruton talks about “a comparable platitude” about beauty which is: ) beauty pleases us; ) one thing can be more beautiful that another; ) beauty is always a reason for attending to the thing that possesses it; ) beauty is the subject-matter of a judgment: the judgment of taste; ) the judgment of taste is about the beautiful object, not about the subject’s state of mind. in describing a object as beautiful, i am describing it, not me; ) nevertheless, there are no second-hand judgments of beauty. there is no way that you can argue me into a judgment that i have not made for myself, nor can i become an expert in beauty, simply by studying what others have said about beautiful objects, and without experiencing and judging for myself; ) beauty, in a person, prompts desire (scruton, ). part | literature study on organizational aesthetics | aesthetics considering the several object-subject perspectives, the similarity of stimuli that cause aesthetic experiences as well as the attributed effects of beauty, catching beauty is an all-encompassing definition seems to be difficult. reber et al. ( ) distinguish three main positions of beauty: ) the objectivism view (based on plato) which has been discussed earlier: beauty is a property of an object that produces a pleasurable experience in any perceiver.; a psychological attempts to identity critical contributors to beauty like balance and proportion, symmetry, informational content and complexity, contrast en clarity (acquinas, birkhoff, gombrich, arnheim). feagin ( , in reber et al, ) stated that beauty is not an objective, but an objectified property which can be valued positive and intrinsic; ) the subjectivist view as an opposite view (‘beauty is in the eye of the beholder’): beauty is a function of idiosyncratic qualities of the perceiver and all efforts to identify the laws of beauty are futile. taste cannot be debated, following the social constructivist emphasis (reber et al., ) and ) the interactionist perspective: rejecting the objective versus subjective distinction, but suggest that a sense of beauty emerges from patterns in a way people and object relate (ingarden, merleau-ponty). based on much recent research (e.g. leyton and ramachandran, ), it seems plausible to conclude that formal properties and expressive properties demonstrably contribute to positive aesthetic experiences (e.g. wagner, ; goldman, ). and this justifies the dominant objectivism view on aesthetics . representational properties are mainly attributed by the perceiver, based on his memories and identification. later in this study will be proved that both three aesthetic properties are recognized in organizations as well. . aesthetic process having aesthetic experiences can be considered as a process (e.g. parker, ; leder et al., ). parker ( ) distinguishes the process of association, objectification and projection of the idea of the self. gagliardi ( ) splits the process into three main phases of observation, interpretation and report. according to gagliardi, ‘it is essential in the first phase that we abandon oneself to what kant called ‘passive intuition’’. several models for describing the aesthetic process have been developed the last decades (weltzel- fairchild, ). parsons model has been trying to account developmentally for viewers´ aesthetic responses by identifying five stages of aesthetic development: ) favoritism: direct stimuli of pleasure, particularly color and subject matter; ) subject (mimetic): focus on the realism of the subject; ) expression: understanding as metaphors for ideas and emotions are valued for the emotions they inspire; ) medium/form/style: style is the carrier of historical thoughts and feeling and has public significance; ) judgment: the personal meaning of the art work is weighted within the tradition to which it belongs. parson ( ) also developed levels of maturity for each stage from judge are own appreciation to judge a work of art positively even you don’t like it: a) based on own opinion / spontaneous; b) based on ‘experience at the moment’; c) based on social context and personal assumptions; d) based on experts; e) appreciation and judgment are separate. housen ( ) developed a scoring manual for aesthetic responses based on nine domains (observation, preference, association, evaluation, comprehension, questioning, assertion, comparison an interpretation) during a five staged process: ) accountive: the viewer is egocentric; ) constructive: the viewer is aware of the language of art but has no theoretical framework; ) classifying: the viewer has a theory and decodes according to knowledge; ) reflective: the viewer searches for symbols to support emotional reactions; ) re-creative: the viewer integrates all previous levels. part | literature study on organizational aesthetics | aesthetics horner ( ) moved away from the empirically defined models of aesthetic experience and developed an model that describes the different levels of response a viewer might experience involved with a work of art. horner suggests that ‘the aesthetic experience offers the viewer greater self- understanding by eliciting personal, subjective, and internal responses by experiencing the following eight phases’. first internal: ) forgetting: entering into a fusion/dialogue with the art work; ) remembering: recalling the journey into the work; ) reflecting: thinking about the whys of the journey; ) revealing: becoming aware of one’s desire and fears. than external; ) describing: decontextualizing the parts of the work; ) structuring: noting the patterns of space of time; ) interpreting: becoming aware of the social discourse; ) retro-activating: assessing the experience contextually. dufresne-tassé rebuilds housen’s model by adding cognition, emotion and imagination. unlike housen’s domains, dufresne-tassé verbs cab deal with activities in which the viewer is orienting herself in relation to the work of art and in which the viewer is other solutions are being offered to a perceived problem, new links, usages, and elements are being made, or new insight may perhaps be gained (ibid). fairchild ( ) who examined the models described before, concludes that ‘none of the preceding models are suitable for describing and analyzing the experience of a viewer’. she developed a mode, based on the dufresne-tassé verbs and the housen’s domains, but now linked to the modes of responses suggested by horner. this results in the following phases of experiencing aesthetics. modes phases operational verbs dream forgetting to fuse with to orient oneself to show feeling to manifest emotion remembering to like, to dislike to recall to note to associate to state to identify reflecting to separate from to differentiate to be aware of play self-revelation to note significance to re-order to change signifier to modify to invent metaphor describing to note, to describe to associate meaning to deconstruct to note symbols structuring to order to map to structure to categorize to compare interpreting to explain to discourse to grasp meaning to infer meaning concept assessing to judge to evaluate to critique to assess table . phases of experiencing aesthetics (fairchild, ) part | literature study on organizational aesthetics | aesthetics an extensively elaborated process of the aesthetic experience is rendered in leder’s et al. ( ) model of aesthetic appreciation and aesthetic judgment. this model consists the following five phases: . perceptual analysis: complexity, contrast, symmetry, order, grouping; . implicit memory integration (influenced by previous experiences): familiarity, prototypically, peak-shifts; . explicit classification (influenced by domain specific expertise, declarative knowledge, interest and personal taste) : style and content; . cognitive mastering (influenced by domain specific expertise, declarative knowledge, interest and personal taste): art-specific-interpretation and self-related-interpretation (search for meaning, cognitive interpretation and orientation, see dewey, ); . evaluation: understanding, ambiguity (cognitive state) and satisfaction (affective state) -> solving perceptual problems is self-rewarding the aesthetic process will lead to aesthetic judgment (a result of the evaluation of the cognitive mastering stage) and aesthetic emotion (an emotional reaction which is a by-product of the processing stages), leder et al. ( ) claim. figure . aesthetic process leder et al. ( ) these phases are quite comparable with the four types of feeling (sequently following) of mitias ( ) offers: ) emotion (exiting the stimuli); ) idea (the character of the work: practical, religious, moral); ) image (structure and unity: what the work has to offer) and ) sensation. mitias argued: ‘when the attitude of sense-perception is effected, when the introductory feelings occupies a prominent place in the imaginations and sustain our interest in the quality which aroused it the aesthetic object begins to unfold in the aesthetic experience which is, perhaps, already under way. we arrive at the aesthetic object by penetrating the form, not going beyond it, for it is immanent in the very form. when we surrender ourselves to certain images, feelings or other types of emotional, intellectual, or historical associations we leave the world potential in the art work and enter the idiosyncratic world of psychological experience.’ reber et al. ( ) suggest that ‘an aesthetic experience is a function of the perceiver’s processing dynamics. the more fluently the perceiver can process an object, the more positive is his or her aesthetic response’. this proposal entails four specific assumptions. part | literature study on organizational aesthetics | aesthetics . objects differ in the fluency with which they can be processed. features that facilitate fluent processing include all the core features identified in the objectivist tradition, like goodness of form, symmetry, figure–ground contrast, as well as variables that have not received attention in traditional theories of aesthetic pleasure, like perceptual and conceptual priming procedures. . processing fluency is itself hedonically marked and high fluency is subjectively experienced as positive, as indicated by psychological findings. . processing fluency feeds into judgments of aesthetic appreciation because people draw on their subjective experience in making evaluative judgments, unless the informational value of the experience is called into question. . the impact of fluency is moderated by expectations and attribution. on one hand, fluency has a particularly strong impact on affective experience if its source is unknown and fluent processing comes as a surprise. on the other hand, the fluency-based affective experience is discounted as a source of relevant information when the perceiver attributes the experience to an irrelevant source. (reber et al, ). because of their extensively elaborated work, let’s cite their own conclusion: ‘in sum, we propose that aesthetic pleasure is a function of the perceiver’s processing dynamics: the more fluently the perceiver can process an object, the more positive is his or her aesthetic response. this proposal entails four specific assumptions. first, objects differ in the fluency with which they can be processed. features that facilitate fluent processing include all the core features identified in objectivist theories of beauty, like goodness of form, symmetry, and figure–ground contrast, as well as variables that have not received attention in traditional theories of aesthetic pleasure, like perceptual and conceptual priming procedures. second, processing fluency is itself hedonically marked and high fluency is subjectively experienced as positive, as indicated by psychological findings. third, the affective response elicited by processing fluency feeds into judgments of aesthetic appreciation, unless the informational value of the experience is called into question. finally, the impact of fluency is moderated by expectations and attribution. on the one hand, fluency has a particularly strong impact when its source is unknown and fluent processing comes as a surprise. on the other hand, the fluency based affective experience is discounted as a source of relevant information when the perceiver attributes the experience to an irrelevant source. one of the strengths of our proposal is its ability to integrate distinct phenomena under a common theoretical framework.’ (reber et al, ). the process stages of parker and gagliardi are very useful. but the aesthetic process of leder et al. ( ) is best developed and validated and has shown to be easily applicable in design disciplines in which aesthetics as well as functionality are aspects of design requirements. part | literature study on organizational aesthetics | aesthetics . aesthetic judgment judgment aesthetic judgment is - besides aesthetic emotion - the result of the aesthetic experience, according to leder et al. ( ). but ‘beauty is in the eye of the beholder’ is a well known phrase, so what is there more to say? like in the whole field of aesthetics, of course, for aesthetic judgment too, the debate is between the subjectivist and the objectivists. or, more designated, the non-realists and realists. aesthetic judgment in an objectivist view assumes that (a degree of) features belonging to an object cause the judgment. ‘an important corollary of this account is that when a spectator affirms that an object is, for instance, beautiful, his judgment must be implying that everyone without exception who judges the object aesthetically, ought to be find it beautiful’ (cooper, ). subjectivists deny this assumption and assume that people come to an aesthetic judgment only by the pleasure or displeasure of the object to arouse in any given spectator. subjectivists have accepted that the aesthetic judgment cannot be conceived as, in intension, a bare statement or expression of personal liking or disliking (ibid). before going into this, let’s chronologically list the insight about aesthetic judgment, starting with kant. many authors have been cited kant because of his groundbreaking work. the following phrases about kant are cited quoted from the stanford encyclopedia of philosophy. for kant, the judgment of taste claims “universal validity”, which he describes as follows: ‘… when [a man] puts a thing on a pedestal and calls it beautiful, he demands the same delight from others. he judges not merely for himself, but for all men, and then speaks of beauty as if it were a property of things. thus he says that the thing is beautiful; and it is not as if he counts on others agreeing with him in his judgment of liking owing to his having found them in such agreement on a number of occasions, but he demands this agreement of them. he blames them if they judge differently, and denies them taste, which he still requires of them as something they ought to have; and to this extent it is not open to men to say: everyone has his own taste. this would be equivalent to saying that there is no such thing as taste, i.e. no aesthetic judgment capable of making a rightful claim upon the assent of all men’ (veenbaas and visser, ). kant's idea is that in a judgment of taste, one demands or requires agreement from others in a way one does not in our judgments about the niceness of roses, which is just a question of individual preference. in matters of taste and beauty, people think that others ought to share their judgment. the judgment of taste has such an aspiration to universal validity that it seems “as if were a property of things”(veenbaas and visser, ). kant argued that judgments of agreeableness have a general validity but not universal validity (veenbaas and visser, ). but in the case of judgments of taste, kant argued, ‘correctness is not hostage to what most people like or judge’. however, kant would probably not go along with this; for he characterizes the normativity in a way that ties in with his eventual explanation of its possibility. kant expresses the normative idea in a very particular way. he wrote: ‘we insist on others agreeing with our taste’; the judgment of taste involves a claim to validity for all men.’ by contrast, kant argued that ‘although we sometimes speak as if our judgments of the agreeable are universally valid (“lamb tastes better with garlic”), in fact they are not: judgments of the agreeable appeal only to most but not to all men.’ so, looking back on kant’s contribution to aesthetic judgment, authentic judgment of taste (or an aesthetic judgment) according to kant is ) subjective, ) disinterested, ) universal, necessary, and ) singular, concerning ) the contemplative pleasure that everyone ought to derive from ) cognitive and imaginative free play in relation to ) forms of finality (carroll, ). part | literature study on organizational aesthetics | aesthetics according to pepper ( ) there are two ways of considering this aesthetic experience event: ) analyze its structure and ) the relation to other objects outside this event. ‘the emphasis here is on relations. the other way is to feel the event as a totality’. aesthetic judgment, advocates by pepper, ‘requires involvedness, physical state of the watcher, the capacity of interweaving with systems of personal strands in the generation of the complex vivid texture (the personal-impersonal vivid textures may be called the aesthetic statue), readiness, relevancy for the watcher and competency to imagine (the personal contribution to the aesthetic work of art)’. hospers ( ) mentions that an aesthetic experience not only cause positive effects on people. ‘a work of art can move you, shock you, startle you into a new awareness, channel your mind into new modes of perceiving, the experience of which you would hardly describe as pleasant.’ ‘having an aesthetic experience will be encountered after the experience itself. by reflecting a person will feel ‘”hey, that was pleasant or beautiful”. ‘enjoyment is often is an investment we make after the fact’, ginsberg argued ( ). mitias ( ) offers four main types of mental ingredients for feeling which will be arise sequentially fusing into each other: emotion (exiting the stimuli), idea (the character of the work: practical, religious, moral), image (structure and unity: what the work has to offer) and sensation. ‘during this event i am one with my experience; i am my experience during that stretch of time (mitias, ). zangwill ( ) proposes two kind of judgments: verdictive and substantive judgment. ‘things can be judged as beautiful or ugly. this can be called a verdictive judgment. when we judge art in terms of dainty, balanced, graceful, delicate or warm, we speak about substantive judgment’. ‘representational properties’ zangwill ( ) stated, ‘are a matter of meaning, substantive properties are not. at most, substantive properties can possess representation. substantive judgments do not describe neutral features of things but ways of being beautiful or ugly. we can put the point in terms of the function of the judgments. the function of verdictive judgments is simply to pick out aesthetic value and disvalue; but the function of substantive judgments is to pick out the substantive properties that determine aesthetic value and disvalue. substantive judgments are there to serve verdictive judgments. substantive judgments are inextricably locked together (the ‘framework principle’).’ in criticism, the value judgment comes first (zangwill ( ) citing greenberg). ‘it is true that listening too others expressing their substantive judgments my persuade us to revise our verdictive judgments. but that is because of our attention has been drawn to certain ways in which things achieve excellence or its opposite. it is more like rhetoric than reasoning’ (zangwill, ). later, zangwill ( b) speaks about “the dialectical situation”: ‘the realist has an easy explanation of the robust normative nature aesthetic truth (‘aesthetic judgments ‘represent what is really in the object’, according to hume). the non-realist, by contrast, has a severe problem; for, if making aesthetic judgments is just a matter of having attitudes or aspect experiences, then why isn’t any attitude or aspect experience as good as any other? both realism and non-realism are on par as far as the experimental aspect of aesthetics is concerned. but when it comes to explaining the normatively of aesthetic judgment , the realist is ahead’, according to zangwill. the distinction is useful, and it marks a real difference between different kinds of concepts and properties. the strategy is: (a) to see judgments of beauty as pre-eminent among other aesthetic concepts and properties; (b) to give a distinctive account of beauty and judgments of beauty; and (c) to locate a necessary link between judgments of beauty and the other aesthetic judgments, which does not obtain between judgments of beauty and non-aesthetic judgments. (zangwill, ) the first distinctive feature is what kant called “subjective grounds”. judgments are made on the basis of a response of pleasure and displeasure. the second distinctive feature is that judgments claim correctness. aesthetic judgments share this with empirical judgments. kant pulled these two distinctive features together. ‘according to simple form of objectivism, the correct application of an part | literature study on organizational aesthetics | aesthetics aesthetic judgment, even one as general a ‘this object is beautiful’, as wholly determined by whether certain qualities or relations are perceived to exist in the object’ (cooper et al., ). ‘an important corollary if this account is that when the spectator affirms that an object is, for instance, beautiful, his judgment must be implying that everyone without exception, who judges the object aesthetically, ought to find it beautiful’. objectivists claim - and proved by leyton and ramachandran - that we obtain satisfaction from perceiving that the parts of show a high degree of formal aesthetic properties (ibid). leder et al. ( ) claims that processing an aesthetic experience ends in two outputs: first, aesthetic judgment which is the result of the evaluation of the cognitive mastering stage. secondly, aesthetic emotion: an emotional reaction which is a by-product of the processing stages of the models.’ the dissociation between judgments and emotional state can be illustrated when, for example, an experienced viewer comes to the judgment that the painting she or he is asked to judge is a poor example of a certain painter. this does not exclude that the process that produced that judgment was not rewarding and experienced as affectively positive. however, more naïve perceivers presumably show a stronger interdependence of both outputs. asking how pleasing an artwork is refers to the aesthetic emotion. liking and preference on the other hand might be differentially related to either output’, leder et al. argue. ‘sensation is the door through which we enter into the experience of beauty; and, again, it is the foundation upon which the whole structure rests. without feeling for the values of sensation, men may be sympathetic and intelligent, but they cannot be lovers of the beautiful’, parker ( ) stated. ‘from a psychological standpoint, sensation is the datum of the aesthetic experience, the first thing there, while its power to express depends upon a further process which links it up with thoughts and feelings. there are two characteristics of aesthetic feeling in its relation to sensations and ideas which must be taken into account in any explanation; its objectification in them and the universality of this connection. expression is embodiment’. (parker, ) scruton ( ) starts with the theorem that ‘with the good, the true and the useful, man is merely in earnest; but with the beautiful he plays’ (schiller in scruton, ). ‘when our interest is entirely taken up by a thing, as it appears in our perception, and independently of any use to which it might be put, then do we begin to speak of its beauty. a functional building or carpet is not, for that reason, beautiful. on referring to architecture as a useful art we are emphasizing another aspect of it – the aspect that lies beyond utility’ (scruton, ). ‘the look of something, when it becomes the object of intrinsic interest, accumulates meaning’, he argues. ‘for example, when we appreciate beautiful things not for their utility only, but also for what they are in themselves, or more plausibly, for how they appear in themselves. the judgment of beauty, it emerges, is not merely a statement of preference’. but scruton also perceives a paradox: ‘the judgment of beauty makes a claim about its object, and can be supported by reasons for its claim. but the reasons do not compel the judgment, and can be rejected without contradiction’. aesthetic reflexivity in relation to aesthetic judgment, the theory of aesthetic reflexivity is interesting. lash and urry ( ) recognize the phenomena of reflexivity which they later translate to aesthetic reflexivity. this growing reflexivity is initially part of a radical enhancement in late modernity of individualization. ‘there is an ongoing process of detraditionalization in which social agents are increasingly 'set free' from the heteronymous control or monitoring of social structures in order to be self-monitoring or self-reflexive’ (schrijver, ). part | literature study on organizational aesthetics | aesthetics much of this literature has its origins in the sociology of science, in which reflexivity means broadly ‘the application of a theory's assumptions to the theory itself, or more broadly the self monitoring of an expert system, in which the latter questions itself according to its own assumptions’(lash and urry, ).they argue that ‘sociologists have extended the notion to include-in place of the self-reflexivity of a scientific community -the increasing of an increasingly individualized lay public reflexively to question the assumptions of science and the expert-systems themselves’. parallel to this phenomenon is another important development in late modern societies. and this is an increasing pervasion of aesthetic reflexivity. cognitive reflexivity has its origins in the rationalist and cartesian assumptions of the enlightenment tradition of modernity. aesthetic reflexivity is rooted in the assumptions and practices of aesthetic modernism, in another modernity (ibid). aesthetic reflexivity is grounded in 'pre-judgments'. ‘cognitive reflexivity assumes a subject-object relationship of the self to itself and to the social world; aesthetic reflexivity assumes a self which is at the same time a being-in- the-world’ (lash and urry, ). lash and urry focus on the reflexivity of a world becoming more and more immanent. they state: ‘as being-in-the-world is an important given in today's society, the subject-object relationship needs a different interpretation than in a cognitive utilitarian framework. in aesthetics, the subject-object relationship has always been a much-studied topic. the subject is always the-usually-rational-analytical- thinking agent, while the object is the unconscious/unaware reagent, by definition lower in the hierarchy’. ‘the subject 'wins' by virtue of rational thought and analytical consciousness’ (schrijver, ). lash and urry argue that ‘as the information society begins to produce an overload of sensory stimuli and nuggets of information, the need to be able to react, and to become part of the network of immanent objects becomes greater’. the distinction between reflexivity and reflectivity becomes important in this context. both terms comprehend a level of awareness and analysis: ‘the capability of a subject to make an assessment of an object and act upon that assessment’ (lash and urry, ). the term reflectivity implies a ‘hierarchical difference between subject and object; the root reflect already denotes a level of rational thought, as well as the difference in value conferred upon an original (the real) as opposed to its reflection (the illusion)’. recently, social thinkers have combined the idea of reflexivity with the aesthetics (felt, sensory- emotional parameters) of everyday experience (sutherland, ). the notion of aesthetic reflexivity arises from considerations of ‘the pressures on the self’ in high modern societies where we are compelled to be highly adaptive, constantly challenged by new perspectives and circumstances (giddens, ; lash and urry, ). ‘aesthetic reflexivity is a mode of dealing with such perspectival and circumstantial incongruities by appropriating the aesthetics of an experience (scenic properties, feelings and sensory-emotional characteristics) as means to managing the increasing complexities of life and work. aesthetic reflexivity is the creation of knowing through the appropriation and transformation of the sensory-emotional characteristics of our experiences’ (lash and urry, ). according to sutherland ( ), ‘the aesthetic workspace is the opportunity to engage in reflexive, critical thinking afforded by the aesthetics of the context created around arts-based activities.’ he refers to the theory of affordances and the concepts of aesthetic workspace and aesthetic reflexivity as frameworks. sutherland argues that three underlying processes that arts-based methodologies deliver in developing this kind of reflexivity: a) experiencing self and others, b) objectifying experience and c) associating experience. denora ( ) argues that 'an environmental appropriation, or consummation of the aesthetic materials that are part of a context, a scene or setting, is how experience comes to be made, felt and known to self’. as individuals engage in such activity the machinery or "work" required of social actors as they configure themselves as agents is made increasingly visible, as an object upon which actors reflect' (ibid). aesthetic reflexivity then is ‘the appropriation and consummation of the sensory- emotional characteristics of experience and reflection on the work of making those experiences. it is part | literature study on organizational aesthetics | aesthetics thinking on the work of self-configuration - which becomes objectified as a cognitive 'object' of experience - amidst new or unknown experiences’ (sutherland, ). ‘aesthetic reflexivity is self-work in which individuals mobilize the aesthetics of experience to develop self-knowledge - who they see them-selves as being, becoming and how they act in relation to more pervasive social contexts. in the realm of arts-based management and leadership development, this focuses on how participants develop reflexive capabilities as they cognitively objectify aesthetic experiences as objects of reflection associated with how they configure themselves as managers and leaders and how these experiences are mobilized to inform future practice’ (sutherland, ). bos ( ) developed a reflexive interactive design approach. reflexive interactive design distinguishes itself from other interactive and participatory design approaches by the following features: . concrete design activities as a central part of the process. . systematic identification and connection of needs and values of stakeholders with the technical and structural characteristics of the design. . second order analysis of problem definitions and requirements, and increasing opportunities synthesis of different needs in a design. no negotiation, but congruence. . choice for both transparent and strategic actorship the professional executive on under a clear command of the financier. reflexive interactive design is thus much over interactive process management. . balance between opening the solution space by the discussion of assumptions and fixed images of what is possible, and providing adequate structure and certainty to the parties to actively participate, not only in the thinking process, but also in doing. . transdisciplinary approach: close link between science and social scientific knowledge, and insights from the humanities (including the philosophy). at the same time in the design process and in the subsequent phases used the explicit and tacit knowledge and experience of stakeholders in the field. . systematic design: thorough needs analysis; separating needs, functions and solutions accurately, creating the widest possible range of solutions for the same function. the resulting programs and requirements morphological charts provide clues for various design processes, adapted to local conditions and specific accents so, for defining aesthetic judgment, again the battle between the subjectivist view and the objectivist view (reber et al., ) doesn’t make it possible to propose a uniform definition. according the objectivist view, aesthetic judgment only must be made based on (aesthetic) properties of observed the object or artifact. following the subjectivist view, beauty is ‘a function of idiosyncratic qualities of the perceiver and all efforts to identify the laws of beauty are futile’ (reber et al., ). taste cannot be debated, following the social constructivist emphasis.’ the claim that ‘beauty is in the eye of the beholder’ represents this subjectivist view, reber et al. ( ) argued. literature on aesthetics in general accept the idea of leder et al. ( ) that aesthetic judgment is a result of the evaluation of the cognitive mastering stage as well cause an aesthetic emotion. to make it much more complex, the theory of aesthetic reflexivity even claims that aesthetic experiences in workplaces effect experiencing self and others, objectifying experience and associating experience. part | literature study on organizational aesthetics | aesthetics psychological antecedents of aesthetic judgment from the psychological literature, especially about decision-making, a number of important comments are relevant on the above, which have implications for the aesthetic judgment of people. these the phenomena are affect heuristic, mere exposure effect, priming, processing fluency, aesthetic induction, prototyping and familiarity and verbal overshadowing. affect heuristic described by zajonc (zajonc, ) and later elaborated by slovic (slovic et al., ) concerns choosing the option which feels most comfortable. representation of objects and events in people’s mind are tagged to varying degrees with affect (slovic et al., ). a study by winkielman, schwarz, fazendeiro and reber ( ) shows that people have a more positive attitude toward stimuli they have seen before. this is also called the mere exposure effect '(zajonc, ). this effect is based on the power of repetition: repetitive exposure to a stimulus creates a more positive assessment of the same stimulus. the observation that ‘mere exposure effects do no depend on a conscious recognition of the presented stimulus’ was one of zajonc’ ( ) claims; affect does not need cognition. later research (e.g., bonanno and stillings, ; mandler, nakamura, and van zandt, ; reber, winkielman, and schwarz, ; rotteveel and phaf, ) strongly suggest that mere exposure does depend on automatic cognitive processes, more precisely, the automatic activation of memory traces. this effect can be related to the aspects of familiarity and prototyping. aesthetic preferences are affected by familiarity. familiarity refers to how familiar or novel an object is (mastandrea, bartoli and carrus, ). familiarity through repetition increases the affective preference for a stimulus (kunst- wilson and zajonc, ; zajonc, ). repetition might reinforce positive experiences due to the lack of negative consequences. repetition shows great affinity with priming. priming concerns the repeated exposure to an (aesthetic) expression which this leads to more positive evaluations. (zajonc, ). this mechanism is widely used in advertising, in which priming of a particular brand cause a more positive attitude toward that brand. prototypicality is the amount to which an object is representative of a class of objects. it is built through experience, and a prototypical object optimally represents a class of objects (leder et al., ). leder and colleagues have been investigated, both variables, ‘prototypicality and familiarity, presumably are not exclusive to art’, they argue. reber, schwartz and winkielman ( ) proposed that art is beautiful when it is easy to process. they introduced the term processing fluency. ‘prototypical, familiar and average complex objects are easier to process’, they argue. ‘high processing-fluency (perception of the identity and the meaning) cause positive feeling, but it is unclear whether low fluency cause a neutral state or negative emotional scale’ (silvia and brown, ). aesthetic induction, described by mcallister (mcallister, ) is ‘applying aesthetic criteria based on empirical observations’. if something repeatedly occurs, one is inclined to like and use it as the criterion for evaluation. ‘aesthetic considerations only contribute to the success of a theory or argument when they show applied, normative and theoretical relevance’ (kuipers, ). mcallister cites the example of scientists who have a positive weight associated with performing aesthetic theories. kuipers ( ) notes that different terms from many different disciplines are overlapping. he suggests that 'aesthetic induction may very well be a variant of the so-called mere-exposure effect, namely, unconscious affective priming´. finally, literature points on the phenomenon that language is a poor medium to describe feelings, such as aesthetic experiences. if we explicitly prompt arguments for and against certain forward options, we are forced to focus on aspects which can be formulated easily. therefore this will have a relatively heavy weight in our opinion. ‘conversely, attention is diverted by considerations which may be very important to our satisfaction, but which is more difficult to articulate’. this phenomenon is called verbal overshadowing(melchionne, ), which was first demonstrated by schooler and engstler- schooler ( ). they indicate that ‘verbally describing a nonverbal stimulus (such as a face) can part | literature study on organizational aesthetics | aesthetics impair subsequent attempts at identification of the stimulus. we dispose of our ‘real judgment’, because this is repressed in what we can express in language. the order to formulate a result, we deceive ourselves about what we consider as really important arguments’. particularly in relation to aesthetic experiences, taylor ( ) introduced the term of aesthetic muteness: the difficulty of expressing aesthetic dimensions of experience in words. according to taylor: ‘in my wilder, giddier moments of speculation i think that overcoming aesthetic muteness may be the key to realizing fully our potential as humans within an organizational context. overcoming aesthetic muteness will make it legitimate to have conversations about how it feels to be in an organization.’ it possibly explains the difficulty of the interpretation and explicating the recognition of the aesthetic formal properties like the ‘the coherence of things’ and ‘the feeling that everything is related to each other’ without being able to indicate what it is. taste speaking about aesthetic judgment is directed to the discussion about taste. taste can be explicated as the ability to correctly judge aesthetic objects and events. more specific, aestheticians agreed for a long time that if a thing possesses a certain set of (formal) properties like ordered, symmetrical and definite, a thing is beautiful. this formalistic view on taste was rejected by hume and kant, who focused exclusively on the qualities of the viewer that make him or her a good judge instead of offering objective-criteria formulae for what makes an object aesthetically good or beautiful. hume and kant were abided by other subjective accounts of aesthetic goodness like sibley, who argue that reductions of evaluative aesthetic claims will never result in arrangements of objective properties. he stated that ‘aesthetic concepts and aesthetic terms as ones that necessarily include taste in their application’. in justifying the use of aesthetic terms, according to sibley, ‘we naturally seek out a basis that does not refer to taste. we look for the objective basis for our use of such terms, and we commonly expect to find such bases’. sibley advised to be suspicious of anyone who says that we can create a rule that states that a certain aesthetic feature can be created by inserting certain non- aesthetic ones. so, in relation to aesthetic judgments, and using zangwill’s ( ) verdictive and substantive judgment, substantive judgments during aesthetic experiences seems to be of the earlier mentioned primary ‘formal’ properties of an object, while the verdictive judgments seems to be related with at least the expressive aspects of an object and may be even with the representational role of it. ‘beauty is in the eye of the beholder’ than, could be fine grinded to the verdictive judgment to ‘judging the representation (evaluative properties) of the object is in the eye of the beholder’…. looking back on the theory of aesthetic judgment and taste can be noted that this judgment is about an intertwined judgment of several properties of the object or the event like formal (substantive), expressive and representative properties which cause a specific more or less meaningful emotion in the observer. measuring aesthetic experiences, judgment and emotions in most studies on aesthetic experiences, judgment and emotions people were asked to reflect on a offered art work. or they were asked to select a preference work of art. jones ( ) suggests a variety of methods for eliciting an organizational member’s aesthetic experience such as direct questioning, indirect questioning, asking for commentary on relived events and drawing feelings. taylor argues that it is difficult for people to represent their own aesthetic experiences through language (aesthetic muteness). he suggests using the technique of storytelling in which respondents have more ‘space’ to express their feelings and judgments (taylor, ). part | literature study on organizational aesthetics | aesthetics . conditions for aesthetic experiences ‘environmental conditions are of paramount importance for the aesthetic experience’, csikszentmihalyi ( ) stated. basically two elements are needed for having an aesthetic experience (mitias, ): a formal structure of an art work and a subjective consciousness of the percipient. the unity of these elements in one event is what creates the aesthetic situation. characteristics of the ‘aesthetic field or situation’ (object, perceiver, creator and performer), are according to mitias intentionally of consciousness, directed towards an object, requiring time, sequence of perceptual events and the performative aspect of the experience (the intimate collaboration between appreciator and the artist) having a specific attitude of the perceiver is a often mentioned feature: intentionally of consciousness, preparations and sensitivity of the perceiver (steinkraus, ), affective state of aesthetic attitude ( cupchik and laszlo, ), certain state to have aesthetic experiences (leder et al., ), attentiveness, curiosity, intrinsic motivation, anticipation of reward and expectation of enjoyment (csikszentmihalyi, ). csikszentmihalyi completed viewers’ features with balance of challenge and skills in the encounter, which give meaning for the encounter. more specific mentioned aspects of the environment in which the aesthetic experience takes place are a safe environment (frijda ( ) cited by leder et al. ( )), a specific context (clean, blank, specious environment, limited information), scale, time (period of maturation), with less social activity (derivation) and relation with other different object being frequently noted (csikszentmihalyi, ). pepper ( ) earlier mentioned an environment ‘which increases fusion, intuition and quality, decrease discrimination, analysis and relations by controlling conflict and organization. conflict by vivifying the quality of an event, organization by extending its spread’. . aesthetic supervenience aestheticians like sibley, zemack, zangwill, parker and scruton are convinced of the idea that a work of art contains aesthetic properties and non-aesthetic properties as well, which is defined as aesthetic supervenience based on the theory of supervenience. it was kant who first touched the aspect of supervenience by distinguishing ‘dependent beauty’ from ‘free beauty’. ‘free beauty’ of a thing is independent of its function, of its history. ‘concept of ‘its function’ in case of ‘dependent beauty’ (kant in zangwill, ). dependent beauty is controversial: ‘is a building beautiful or elegant just as a building, or more narrowly as a certain sort of building?’ (zangwill, ). and also the distinction between good, truth and beauty is about supervenience by showing two examples. ‘the scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful…. intellectual beauty is what makes intelligence sure and strong’ (poincaré ( ) mentioned in girod et al., ). the nobel price-winning physicist chandrasekhar has exemplified this thinking by quoting the mathematician weyl: ‘my work always tried to unite the true with the beautiful; but when i had to choose one or the other, i usually chose the beautiful’ (reber et al, ). the aspect of supervenience is art is often mentioned in architecture where functionality and aesthetics meet each other or more than that. architect louis sullivan argues that beauty in architecture (and by implication in the other useful arts) arises when form follows function. in other words, ‘we experience beauty when we see how the function of a thing generates and is expressed in its observable features. function cease to be an independent variable, and becomes absorbed into the aesthetic goal’ (scruton, ). part | literature study on organizational aesthetics | aesthetics the term supervenience was introduced by kim ( , ; savellos and yalçin, ). he did major research on this topic examining the mind-body supervenience. he rejects the functionalistic view which arguing that mental properties as ‘physically realized’ and that makes mental properties almost physical but not quite. the functional conception of mental properties as second-order properties having physical properties as they realize gives rise to difficulties in explaining the causal powers of mental properties, according to kim. kim suggests the idea that ‘mental-event or –state kind has a neural substrate of correlate, too, is a form of mind-body supervenience. it assumes that if two organisms (like organizations) are in identical neural states, they cannot be in different mental states’. sibley's papers ‘aesthetic concepts’ and ‘aesthetic / non-aesthetic´ were pioneering discussions of the dependence of the aesthetic on the non-aesthetic (sibley , ). he argues that ‘there are ) non-aesthetic necessary conditions for applying an aesthetic predicate to an object and ) non- aesthetic sufficient conditions not applying an aesthetic predicate to an object, but there are no non- aesthetic sufficient conditions for applying an aesthetic predicate to an object’ (cited by zemach, ). sibley maintains that, ontologically, ‘x has such and such aesthetic properties because of the non-aesthetic properties it has. non-aesthetic descriptions often inform us about aesthetic qualities of things’, according to zemach. according to sibley, ‘we also think that beauty, ugliness and other aesthetic properties depend on non- aesthetic properties. ´the aesthetic quality depends upon a unique combination of just these colors and shapes so that even a slight change might make all the differences´. dependence contrasts with mind-independence in that it says what aesthetic properties do depend on, as opposed to what they don't depend on: the aesthetic properties of a thing depend on its non-aesthetic properties. this dependence relation implies (but is not identical with) the supervenience relation or relations: (a) two aesthetically unlike things must also be non-aesthetically unlike; (b) something couldn't change aesthetically unless it also changed non-aesthetically; and (c) something could not have been aesthetically different unless it were also non-aesthetically different. these are, respectively: cross- object supervenience, cross-time supervenience, and cross-world supervenience’. although the phenomena of the aesthetic supervenience is widely accepted, goldman ( ) denies that the link between a works’ objective properties and its evaluative aesthetic properties is logically a reductive link (involving necessary and sufficient conditions), conceptual (involving meaning relations), a critical one (involving non-inductive relations short of entailment), or one of supervenience (the idea that necessarily a change in a work’s evaluative properties requires a change in some of its objective properties). ‘the link is simply inductive or causal: in making evaluative judgments, critics are implying that others with similar tastes will react to the same objective properties in the same ways, if free o shortcomings of attention, interest experience or sensitivity’ (bender, ). zemach ( ) argues that ‘an aesthetic property – a degree of unified significance – is a non-aesthetic property when viewed through the medium of desire. he argues that aesthetic and non-aesthetic properties are not only inductively related. the relation phenomenal properties to physical ones may be contingent; we have no clue why nerve spiking and make us sense a coffee aroma and not a timpani sound’, zemach mentions. why does the aesthetic supervene on the non-aesthetic? ‘the simplest explanation of supervenience is by identity’, according to zemach. ‘if every aesthetic property is reducible to an arrangement of non-aesthetic property, the every difference in aesthetic properties is a difference in non-aesthetic properties, zemach argues. an aesthetic property cannot change without change in non-aesthetic properties, because each aesthetic property is identical with some non- aesthetic properties’, he continues. wagner ( ) claims that evaluative aesthetic properties supervene on the non-evaluative aesthetic properties. using the classification goldman ( ) made, non-evaluative properties are formal properties and expressive and evaluative properties represent pure properties (like beauty and part | literature study on organizational aesthetics | aesthetics elegance), evocative properties (like power or amusement) and emotive properties (like joy and delight), she makes a more specific interpretation of the relationship between types of aesthetic properties and the relation with non-aesthetic properties. zangwill ( ) talks about two-way independence: ‘on the one hand, nature can have aesthetic properties; on the hand, works of art can have many kinds of properties apart from aesthetic properties. a fundamental principle is that aesthetic properties are determined by or are dependent on non-aesthetic properties. things come to have aesthetic properties because of or in virtue of their non-aesthetic properties. this means that if something has an aesthetic property then it has some non-aesthetic property that is sufficient for the aesthetic property’. ‘in order to see a thing as having dependent beauty, one must see it as a thing of a certain kind, where that kind implies a function whether natural or artifactual and we must bring knowledge of the history of the thing to bear in our experience. since what gives something a function is external to the thing itself, it is not manifest to someone who is simply perceptually confronted with the thing’. (zangwill, ). parker ( ) started his story about supervenience by arguing that ‘the relation between form and content, and these have a unique aesthetic significance. for there, as we know, the elements of the medium, colors and lines and sounds, and the patterns of these, their harmonies and structures and rhythms, are expressive, in a vague way, of feeling; hence, when the artist employs them as embodiments of his ideas, he has to select them, not only as carriers of meaning, but as communications of mood.’ in the arts, he continues, ‘which we have studied so far, beauty has been the sole or chief end; in the industrial arts, beauty can be only a part of their total meaning. no matter how much of an artist a builder or a potter may be, he is necessarily controlled by the practical needs which houses and pots subserve. this was the original condition of all artists; for “in the beginning,” before life’s various aims were distinguished and pursued in isolation, the beautiful was always married to some other interest. those works in which the unity of the useful and the beautiful is still preserved. in our definition of art we insisted upon the freedom of beauty and the contrast between the aesthetic and the practical attitudes, yet now we are admitting that some things may be at once useful and beautiful. it is impossible to solve the problem by supposing that in the industrial arts beauty and utility are extraneous to each other, two separable aspects, which have no intimate connection. for the fact that a bridge spans a river or that a church is a place of worship is an element in its beauty. the aesthetic meaning of the object depends upon the practical meaning. it is a pleasure in seeing how the purpose is expressed in the form and material of the object, not a pleasure in the possession of the object or an enjoyment of its benefits. i may take pleasure in the vision of purpose well embodied in an object which another man possesses, and my admiration will be as disinterested as my appreciation of a statue. and even if i do make use of the object, i may still get an aesthetic experience out of it, whenever i pause and survey it, delighting in it as an adequate expression of its purpose and my own joy in using it. then beauty supervenes upon mere utility, and a value for contemplation grows out of and, for the moment, supplants a value in use’. (parker, ) ‘and we can understand how enthusiastic workmen, whose admiration for their work is already aesthetic, must necessarily desire to consecrate and communicate this feeling by beautifying the appearance of their products; how inevitably, through the ages, they have made things not only as perfect as they could, but as charming’, according to parker. scruton ( ) was challenged by the question why people experience beauty in architecture. the experience of beauty in architecture, for example, he noted, ‘cannot be detached from knowledge of the function that a building must serve; the experience of human beauty cannot be easily detached from the profoundly interested desire which stems from it. the awareness of purpose, whether in the object or in ourselves, everywhere conditions the judgment of beauty, and when we turn this part | literature study on organizational aesthetics | aesthetics judgment on the natural world it is hardly surprising if it raises, for us, the root question of theology, namely, what purpose does the beauty serve? and we say that it serves no purpose but itself, then whose purpose is that? () whenever people attempt to close up to the redundancy of practical reasoning by choosing between appearances, the also disposed to interpret those appearances as intrinsically meaningful, and to present the meaning that they discover trough a kind of reasoned dialogue, the goal of which is to secure some measure of agreement in judgment among those who have an interest in choice’, scruton stated. the aspect of aesthetic supervenience is a complex matter. for a better understanding and possible application of aesthetic supervenience in organization design, possibly can be learned from design disciplines in which functionality and aesthetics both seems to be important. following the theory of aesthetic supervenience and its relationship to organizational aesthetics, the empirical study has proved that organizational aesthetic stimuli (oas) are be perceived in ‘traditional’ objects and artifacts in organizations (e.g. the components of the esh-model) such as culture, structure, interaction and products and services. . aesthetics in design disciplines after concluding that aesthetics isn’t explicitly part of current design principles within organizations, these combination must be searched in other disciplines wherein aesthetic plays an important role in the act of the design process. such disciplines like product design and multi-media design, architecture, garden en landscape design and dance. in these disciplines functionality and aesthetics have an important role as well in the design process as well in its result. aesthetics supervene on the functional features of the design or even sometimes forms the function itself. this paragraph describes the general accepted design principles of respectively product design and multi-media design, architecture, garden en landscape design and dance product design thinking of product design and specifically the used principles in the design field, leonardo da vinci needs to be mentioned first. he developed the so called ‘seven da vincian principles’. these principles are drawn from an intensive study of the man and his methods. these are: a. curiosità: an insatiably curious approach to life and an unrelenting quest for continuous learning; b. dimostrazione: a commitment to test knowledge through experience, persistence, and a willingness to learn from mistakes; c. sensazione: the continual refinement of the senses, especially sight, as the means to enliven experience; d. sfumato (literally ‘going up in smoke’): a willingness to embrace ambiguity, paradox, and uncertainty; e. arte/scienza: the development of the balance between science and art, logic and imagination. ‘whole-brain’ thinking; f. corporalita: the cultivation of grace, ambidexterity, fitness, and poise and g. connessione: a recognition of and appreciation for the interconnectedness of all things and phenomena (systems thinking). kumar and garg ( ) examined the aesthetic principles for product design distinguishes two approaches which focus on the connection between product design and emotions: a) focusing on the features and properties of a product’s design and the nature of consumers’ responses to them and b) focusing on the cognitive and psychological processes involved in consumers’ responses to aesthetic part | literature study on organizational aesthetics | aesthetics information. these two approaches can be return to those two similar perspectives in the aesthetic literature. kumar and garg ( ) also examined cognitive appraisal combined to form several commonly experienced emotions. these appraisal are pleasantness, responsibility, certainly, attentional activity, effort and situational control. in the context of product design they cite desmet ( ) and ellsworth ( ) who distinguishes fourteen different types of emotions in consumers: desire, inspiration, admiration, amusement, satisfaction / dissatisfaction, pleasant / unpleasant surprise, disgust, indignation, contempt, disappointment, and boredom. they also argue that ‘the first encounter with a product if a consumer finds the compositional properties of a product to be unfamiliar beyond a critical threshold, the consumer will devote more attentional resource to study the stimulus. the consumer may further process the aesthetic information subconsciously, and make a gestalt appraisal about the pleasantness of the product’s design’. one of these compositional properties is harmony which kumar and garg define as ‘the degree to which the visual resources of a composition’s design form a coherent, unified pattern’. people generally prefer harmony to disharmony, even in a composition with variety of design elements. kumar and garg did some empirical research which shows that consumers appraise moderate levels of harmony as more pleasant than extreme levels of harmony. they suggest that ‘designers want to capture the attention o consumers by creating highly atypical designs, they should try to create a greater degree of harmony to evoke appraisals of pleasantness to compensate for the higher attentional resources that they will require the consumer to summon’. veryzer ( ) who examined the aesthetic response and the influence of design principles on product preferences came up with similar results. ‘proportion, which refers to the size relation to one part to another and to the whole, and unity, which refers to the organization of parts such that they interact in a mutually supportive fashion, both are applicable across a diverse range of products. which implies that these design principles may play an important role in many, if not most, consumer purchase decisions’ he argued. veryzer et al. ( ) examined later the influence of unity and prototypically on aesthetic responses to product design and builds on the theory of the gestalt-theory which stated that ‘beauty is dependent on the degree to which an object displays relations consistent with the gestalt laws of organizations like ‘good continuation’ and ‘good shape’ realized by aspects like unity’. prototypically can be used as a concrete design principle, according to veryzer et al., namely, ‘common designs already existing in the marketplace can be systematically altered to make them less typical. and second, the use of prototypically refers to the subjective perceptions of typically or category representativeness’. there is evidence (e.g. barsalou, ; loken and ward, ; langlois and roggman, ) that people respond most favorably to objects that are high prototypically and less favorably to objects that are less prototypically. the research of veryzer et al. provides strong evidence for positive effects of prototypically and unity on aesthetic responses to product design. they also provide a clear demonstration of a unity effect that is not confounded with other factors. also hekkert ( ) and hekkert and leder ( ) argues that prototypically besides novelty or originality are the two features of an object which have been shown to be related to aesthetic preference. ‘preferred are products with an optimal combination of both aspects, according to hekkert. he also perceives that the strategy product design from ‘less is more’ in the fifties and sixties changed to more sustainable design by making a consumer’s experience with products more richer and more meaningful in the s (‘soft design’)’. hekkert ( ) who studied the aesthetic experiences for product design established four principles for what he called ‘aesthetic pleasure’. they are ) the maximum effect for minimum means, ) unity in variety, ) most advanced, yet accepted and ) congruency / appropriateness. part | literature study on organizational aesthetics | aesthetics the first principle of maximum effect for minimal means could be considered as the overarching principle, according to hekkert. he mentioned the examples of chess move, building, or any other solution or design is considered beautiful or pleasing when a great effect is attained with only a minimum of means. ‘as long as people agree on the magnitude of the effect and similarly estimate the amount of means applied, they will agree on the aesthetic attractivity of the result’. the second principle of unity in variety (often mentioned by aestheticians) and its related ordering principles of grouping, contrast, closure, and isolation, most likely end up in aesthetic universals. ‘experiencing unity requires sensitivity to perceive the, sometimes hidden, structure’. for that reason, hekkert stated, ‘some pieces of modern music can only be appreciated by a trained ear that is receptive to the principles of unity that are below the surface’. the third principle, the maya principle (most advanced, yet accepted), assumes that ‘people will only prefer the same product or musical piece when they agree on the degree of originality and typicality’ (hekkert, ). ‘since these ratings very much depend on personal experiences and interests with and exposure to these and like products, the maya principle will often lead to individual differences’, according to hekkert. the fourth principle, congruency or appropriateness, agreement will arise when we agree on the quality all components have to be congruent with. hekkert mentioned the example of the components of a product. ‘they can be congruent with respect to their intensity, but incongruent when it comes to their semantic meaning. the type of product, its function, and the context in which it is used will probably (co-)determine this quality. these principles can predict and explain people’s aesthetic responses’, according to hekkert. ‘when these principles are ‘correctly’ applied, it is most likely but not necessary that people will agree on the aesthetic value. sometimes differences will arise at the group level, when a group shares the same underlying characteristics – we often refer to such a group as a culture -, sometimes even at the individual level. the best recommendation, however, we can give a designer is to obey these principles unless you have very good reasons to violate them.’ ozenc ( ) remarks a changing role of product design. he states: ‘design communities have been engaged in an ongoing transition from usability to experience with an urge to develop a holistic and yet detailed understanding of people. traditionally, experience is defined as the form of one's interaction with the environment. this interaction is characterized as one's ‘doing’ and the environment's ‘undergoing’. such a relationship between oneself and the environment can be interpreted as a constant struggle between the ‘changing’ and ‘unchanging’ character traits of the self, the environment, or both.’ to overcome this transition, according to ozenc, product designers should apply four shifts into their designs: material shift: technology has transformed the materiality of products. products were designed with immaterial materiality of products, where motion and action served as material. form shift: products changed their form from physicality to experience and service. function shift: the functionality of a product becomes interactive between people and the environment. in describing actions, there are several approaches. the diffusion of interaction can be traced back to the interpretations of action across state-of-the-art de sign approaches. the activity theory defines actions as operations and materials of activities, whereas the situated action theory defines actions as generative mechanisms and manners of contingencies. from a distributed cognition perspective, actions are functions between two cognitive machines, the human and the computer. manner shift: technology transformed the social mores and fabric of relationships by the flattening of contexts, multi-contexting, and the emergence of new social mores. part | literature study on organizational aesthetics | aesthetics according to dieter rams, well known industrial designer of braun, good design does have ten characteristics. the design: ) is innovative: the possibilities for innovation are not, by any means, exhausted. technological development is always offering new opportunities for innovative design. but innovative design always develops in tandem with innovative technology, and can never be an end in itself; ) makes a product useful: a product is bought to be used. it has to satisfy certain criteria, not only functional, but also psychological and aesthetic. good design emphasizes the usefulness of a product whilst disregarding anything that could possibly detract from it; ) is aesthetic: the aesthetic quality of a product is integral to its usefulness because products we use every day affect our person and our well-being. but only well-executed objects can be beautiful; ) makes a product understandable: it clarifies the product’s structure. better still, it can make the product talk. at best, it is self-explanatory; ) is unobtrusive: products fulfilling a purpose are like tools. they are neither decorative objects nor works of art. their design should therefore be both neutral and restrained, to leave room for the user’s self-expression; ) is honest: it does not make a product more innovative, powerful or valuable than it really is. it does not attempt to manipulate the consumer with promises that cannot be kept; ) is long-lasting: it avoids being fashionable and therefore never appears antiquated. unlike fashionable design, it lasts many years – even in today’s throwaway society; ) is thorough: down to the last detail. nothing must be arbitrary or left to chance. care and accuracy in the design process show respect towards the consumer; ) is environmental-friendly: design makes an important contribution to the preservation of the environment. it conserves resources and minimizes physical and visual pollution throughout the lifecycle of the product and ) is as little design as possible: less, but better – because it concentrates on the essential aspects, and the products are not burdened with non-essentials. back to purity, back to simplicity. qua design style rams considers his style as ‘less, but better’, as a variation on the dominant design stream ‘less is more’ at the end of the th century in europe (see http://www.vitsoe.com/en/gb/about/dieterrams/gooddesign). roozenburg and eekels ( ) described the fundamentals and methods of product design. first, they argued that a design is made by people for its properties. because of these properties it can fulfill one or more functions. by fulfilling functions a design satisfies needs, and this gives people the possibility to realize one or more values. schematically, this causality is the following. figure . design fundamentals roozenburg and eekels ( ) ‘meaning is a central concept for human-centered design’, krippendorff ( ) starts his contribution at the design research society (drs) in . ‘designers of common artifacts cannot bypass the fact that different artifacts have different meanings to different people, usually related to their cultural backgrounds, expertise, particular interest, and the nature of the situation or context in which they face the artifacts of interest to designers. this empirical fact would make it a mistake to talk about forms as having meanings without reference to who perceives them as such. it would be a mistake for designers to believe they could design meanings into products. it would also be a mistake to follow the old paradigm of designing something to serve a particular function – as is common and appropriate in engineering’, he continues. designers extended the dominant part-whole determinism of functionalism to the relationship between the form of products and the functions they were meant to serve. this is evident in louis sullivan’s ( ) aesthetic formula ‘form follows function’. ‘following’ meant logically derivable from a correct understanding of the functions that an artifact had to satisfy. later esslinger, apple’s main form properties needs values function part | literature study on organizational aesthetics | aesthetics product designer, consequently translated his statement ‘form follows emotion’ into apple products. krippendorff claims ten design principles starting with the axiom of product semantics: ‘ ) we do not respond to the physical qualities of things, but to what they mean to us; ) the meaning of an artifact is its set of anticipated uses. to be known by designers, meanings need to be articulated; ) artifacts are languaged into being. the fate of artifacts is decided in language. artifacts acquire social significance in narrative and dialogue. and he continues: ) design is intrinsically motivating and constitutive of being human; ) design is not the exclusive privilege of a profession; ) understanding others’ understanding or second order understanding – without prejudices and preconceptions; ) cooperative design means bringing stakeholders’ understanding into design processes; ) inscribing (re)designability into a design; ) the (re)designability of artifacts amplifies design. it brings forth a culture that increasingly understands itself as design-driven, no longer information-driven and ) design can succeed only when it inspires and sustains sufficiently large networks of stakeholders.’ krippendorff ends his contribution with six design steps of which he suggest that ‘designs that ignore these six steps (in whichever form), are not likely to succeed. these steps are: ) . envisioning possible worlds, creating a design space that includes not only what designers can vary or compose but also what the future occupants of these worlds, other designers, and the stakeholders in these worlds might consider desirable; ) reducing or modifying these possible worlds according to what the stakeholders of a design can imagine and are willing to live with; ) finding ways to ascertain the vocabularies for meanings that future stakeholders can be expected to bring to a design; ) working out one or more paths to realize a design that might attract stakeholders who could collaborate in bringing the design and desirable future to fruition with present resources or resources that they might become available along that path; ) enrolling stakeholders in the process of realizing a design and ) finding backing for the semantic claims that designers make in their proposals. pham ( ) who examined the relation between nine aesthetic properties (principles: balance, proportion, dominance / principality, alternation / interchange / contrast, graduation / continuity, solidity / structural coherence, simplicity, dynamics and rhythm and three basis characteristics that influences the aesthetic of a product (shape, composition and physical attributes), developed a matrix in which these variables link with the nine principles. pham concludes that ‘the variety of aesthetic judgments and emotional responses are obtained not at random, but in a more controlled and exhaustive manner which exert the most impacts’. he also believes that his systematic framework will add much useful knowledge towards (computer supported) design for aesthetics in a number of ways. in the finishing stage of a design the variables can be manipulated and further refined to improve its aesthetic appearance. ict and multi media parizotto-ribeiro and hammond ( , ) did some similar research specific for the design of computer screen design. they first distinguish three levels of emotional design: ) visceral design which is concerned with appearance and it doesn’t depend on cultural aspects; ) behavioral design which is related to the brain process that processes and control everyday behavior. it deals with pleasure an effectiveness of use and ) reflective design, the highest level, which considers the message, meaning of the product and is culturally dependent. they state that ‘the three levels dimensions are interrelated in any design and, despite being so different, there is no design, according to them, without all the three’. they, like as other studies do, propose next fourteen aesthetic measures for assessing graphic displays completeness: (balance, equilibrium, symmetry, sequence, cohesion, unity, proportion, simplicity, density, regularity, economy, homogeneity, rhythm, and order and complexity). several studies (e.g. ngo, teo and byrne, ) suggested that these measures may help gain users´ attention and build their confidence is using computer systems. part | literature study on organizational aesthetics | aesthetics like kumar and garg, also parizotto-ribeiro and hammond refer to the gestalt theory. this theory first arose in as a reaction to the prevalent psychological theory of the time - atomism. atomism examined parts of things with the idea that these parts could then be put back together to make wholes. atomists believed the nature of things to be absolute and not dependent on context. gestalt theorists, on the other hand, were intrigued by the way our mind perceives wholes out of incomplete elements. according to the gestaltists, ‘things are affected by where they are and by what surrounds them what possibly makes that things are better described as ‘more than the sum of their parts’. parizotto-ribeiro and hammond conclude that users appreciated better the screen layout that applied the design principles than the ones that did not. they even conclude that aesthetic substitutes the usability of software. unity and rhythm seemed to be the most important principles, followed by proportion and homogeneity; balance seems to be the less important principle in this study. they also conclude that these aesthetic aspects amplify the identification, stimulation and pragmatic aspects of the use of the design. zain et al. ( ) did comparable research on web page interfaces, but focused on the relations between aesthetics and learnability of interfaces. especially they measured the substitution of formal seven properties (balance, equilibrium, symmetry, sequence, rhythm, as well as order and complexity) to the factors of the arcs- model (motivation model in courseware design of keller and suzuki ): ) attention: good layouts will attract the attention of the student; ) relevance: good layouts will be relevant to the student; ) confidence: good layouts will boost the student’s confidence and ) satisfaction. they confirmed the claim that aesthetics did affect students learning. and stated that it was still quite convincing to claim that aesthetics played its role in affecting students’ learning motivation. zhang ( ) examined principles for designing motivating information and communication technology and starts his article with the following statement. ‘as a human-made thing, information and communication technology is, ideally, purposely envisioned to fulfill human needs and to support human values. creation and design should then be guided by such understanding. information and communication technology eventually should be used for its intended purpose. such use should be within a certain context, and should affect humans and their surroundings. the emphasis is on how to design information and communication technology in such away that they fit naturally into human lives and human organizations, and cause the desirable effects’ he argued. without explicitly mentioning, he seems to builds on the well spread hierarchy system of motivational needs of maslow which distinguishes the psychological needs, safety and security, a sense of belonging, esteem, cognitive needs, aesthetic needs, and need for self-realization and self- transendence. zhang also seems to use the two-factor theory of herzberg and colleagues (herzberg et al., ). they distinguish two types of factors, namely motivators (intrinsic to the work itself like achievement, recognition and responsibility). zhang points that a design theory can take one or several perspectives. he is citing malone ( ) who listed four perspectives for design-oriented theories for organizational interfaces: information processing perspective, motivational perspective, economic perspective, and political perspective (malone ). he deliberately chooses a motivational perspective on design because ‘it explains human’s various needs, the relationship among needs psychological states attribution, and environmental factors and their impact on goal-oriented commitments’. from this perspective he developed design principles. according to zhang, ‘principles are more fundamental, widely applicable, and enduring’ (shneiderman et al. ). design guidelines, on the other hand, are narrowly focused (shneiderman et al. ), specific and context-dependent rules for designers to follow (te'eni et al. ). design principles are primarily derived from theoretical understandings of humans and their interactions with environments but also based on design experiences and practices, thus design principles are also called heuristics (nielsen ; nielsen ; shneiderman et al. ). by focusing part | literature study on organizational aesthetics | aesthetics on design principles from a motivational perspective, our work is one step closer to a motivational design theory. zangh offers an overview of design principles, which possibly can be used for organization design as well. table . motivational needs zhang ( ) zhang’s ( ) proposed design principles show strong conventions with weick’s ( ) properties for sense making. both emphasize the importance of identify construction, the stimuli in (sensible) environments and interaction in social encounters. world’s most dominating software supplier, microsoft, uses for the design of windows the following eight design principles: ) reduce concepts to increase confidence (e.g. have you introduced a new concept? why? is it necessary?; are you making meaningful distinctions?; does the ux continue the same concept?); ) small things matter, good and bad (e.g. what are the important "small things" seen often or by many?; don't cut the small things in your experiences;); ) be great at "look" and "do"(e.g. what is your ux great at? does its look reflect what it is great at?); ) solve distractions, not discoverability (e.g. reduce distractions; commit to new functionality); ) ux before knobs and questions (e.g. turn down the volume of questions; ask once) ) personalization, not customization (e.g. does the feature allow users to express an element of themselves?; have you made the distinction between personalization and customization?); ) value the life cycle of the experience (e.g. consider the user experience at all stages; walk through the experience as if it has been used for months) and ) time matters, so build for people on the go (e.g. all ux principles apply equally at - inch and -inch screen sizes; be interruptible). architecture the threefold of utilitas (functionality), venustas (aesthetics) and firmitas (construction and sustainable) have been used since the first designs of buildings like temples, churches and castles quite usual. architect louis sullivan argues that beauty in architecture (and by implication in the other useful arts) arises when form follows function. in other words, ‘we experience beauty when we see how the function of a thing generates and is expressed in its observable features. function cease to be an independent variable, and becomes absorbed into the aesthetic goal’ (scruton, ). function has a wide range of denotation, especially in architecture. function may fix on economic, political, technical, aesthetic, ethic or environmental factors, where it may denote the goal of usefulness, the goal of the affordable, the goal of attracting attention and so on (scruton, ). function also denotes a digital product’s semantics, thus functions largely equals content. a classical rule for architects and product part | literature study on organizational aesthetics | aesthetics designers says ‘form (ever) follows function’ (introduced by louis sullivan in ). this has been the basic motor for modern design. combining these two statements, we could say that ‘form follows meaning’, according to schmid-isler ( ). garden and landscape design olascoaga ( ), who wrote a phd-thesis about appraising aesthetic qualities of cities, distinguished formal (directionality, sequential relationships, spatial relationships, solids and voids relationships and overall organizational properties) , expressive (sensory qualities, collative properties, anthropomorphic properties) and representational (denotative meanings and commutative meanings) properties. besides these common properties, he also defines evaluative properties like pretty, nice, and beautiful in order to qualify the aesthetic judgments. he first measured criteria for public appraisal of townscapes. and second, he qualitatively analyzed aesthetic base properties form appraisal places. one of the most widely studied theories in environmental psychology is the mystery / complexity / legibility / coherence model of kaplan et al. ( ) (stamps, ). the theory postulates that people will have two basic needs in environments: to understand and to explore. ‘moreover, these needs might refer to what is immediately perceptible, or might refer to what might be perceptible if one moved to another location. when the two needs are crossed with the two levels of immediacy, four variables are created. the four variables were called ‘informational variables’’’ (kaplan et al ). the labels used for the informational variables are coherence (immediate understanding), complexity (immediate exploration), legibility (inferred understanding) and mystery (inferred exploration). all four informational variables were suggested as predictors of environmental preferences (stamps, ). coherence represents how well a scene hangs together and how easy is it to organize and structure the scene. legibility represents how easy would it be to find your way around the environment depicted to figure out where you are at any given moment or to find your way back to any given point in the environment. complexity is about how much is going on in the scene, how much there is to look at, how much ‘the scene contains a lot of elements of different kinds’. and mystery emphasizes how much a scene promise more if you could walk deeper into it. garden and landscape design is partly a consequence of the aesthetics aspects of natural and environmental aesthetics. in this context the term biomimicry could be interesting. biomimicry is the study of natural models, systems and processes serve as a basis for human problems. the word comes from the greek words bios, which means "meaning of life”, and mimesis, meaning 'to imitate'. humanity has often looked to nature for inspiration to solve problems. one of the early examples of biomimicry is the study of birds to human flight possibilities. although leonardo da vinci ( ) never succeeded in to create a "flying machine", he was a keen observer of the anatomy of birds and bird flights, and made many notes and sketches of various "flying machines". the wright brothers, who in succeeded in building the first airplane, took their inspiration from observing birds as well. dance and theater smith-autard ( ) mentioned in her practical guide for teachers of dance eight so called elements of construction of a dance: the motif (foundation of construction), repetition, variation and contrast, climax or highlights, proportion and balance, transition, logical development and unity (the overall constructional element) which can be achieved by employing the seven mentioned elements (formal properties). according to smith-autard, ‘the motif or foundation of construction only emerge as dominant in the light of all other constructional devices used. here, implicitly she refers to the theory of the aesthetic properties supervene on the non-aesthetic properties’. she stated: ‘without repetition, the motifs would be forgotten; without variation and contrast, repetition of the motifs would be dull if presented ad lib in their original form; a dance lacking climax or highlights would seem to have motifs which have no content worth highlighting; without careful proportioning and balancing of the whole work each of the motifs could become almost eliminated or even too dominant; without transitions the motifs would be isolated movement statements. transitions between each movement part | literature study on organizational aesthetics | aesthetics within the motif and between the motifs are important in defining the phrase and section shaping of the dance; without logical; development from motif to motif, the theme of the dance would be blurred and finally, the motifs contains the main ingredients which provide the unifying threads for the whole work. these include style, qualitative colour, light and shade, line and shape in space, and types of action which motivate the rest of the work’. theatre than, looking forward to organization design, according to zandee and broekhuijsen ( ) of all arts-based metaphors, the idea of organization as theatre is perhaps the most dominant (citing cornelissen, ; taylor and hansen, ; mccarthy et al. ) and the exploration of connections between theatre and organization in increasingly popular and well developed (citing clark and mangham, ; schreyögg and höpfl, ). zandee and broekhuijsen notice that ‘the dramaturgical view that organizational life can be seen as theatre (citing goffman, ; mangham and overington, ; vaill, ) is an attractive one because it is not difficult to find resemblance between theatrical and organizational performance. furthermore, in both domains it is expected that such performances are being prepared and delivered on time, within budget, and in an accurate manner (citing austin and devin, ). this accessibility and transferability (citing vera and crossan, ) of the theatre metaphor may at the same time hamper its potential for truly new and surprising insights into, for instance, identity and role enactment within an organizational context (citing cornelissen, ).’ zandee and broekhuijsen also conclude that studies of the theatre craft and the use of theatre in organizations have in common is ´that they are often based in personal experiences, or close observations thereof, with the processes of theatre production’ (zandee and broekhuijsen, , p. ). mccarthy et al. ( ) claim that ‘the basic premise of the dramaturgical perspective is that people behave and express themselves according to the situations they face, i.e. they put on an act.’ they propose the three ‘p’s of dramaturgy (citing grove et al., ) for enhancing a service customization which are performance and the types of scripts and improvisation capabilities required to deliver service customization configurations and the other two p’s’, participants (employees and customers) and the physical setting. green ( ) cites rochelle mucha, president of business as performance art and author of ´aesthetic intelligence: reclaim the power of your senses.´ she states that aesthetic intelligence in theater is defined by three elements: . presence, which is not simply being somewhere, but being self-aware and aware of others. . authenticity, which entails knowing and understanding the role that one is taking on in business interactions. . synthesis, which mucha said involves seeing overall themes, pulling together disparate information and recognizing what is not said overtly. ´by integrating the three aspects of aesthetic intelligence into an organization's culture - creating connection among employees - business leaders can start the company on the path to creativity and innovation´, according to green. de volkskrant, a dutch newspaper, devoted on april a special section on beauty. famous dutch designers were asked what they consider as beautiful in design. below their statements are listed. part | literature study on organizational aesthetics | aesthetics designer what does beauty mean in your work? how do you achieve beauty in a design? gijs bakker, product designer nothing and everything simultaneously. i just want an idea in my head is in the form of an elaborate product. beauty is the result thereof all ingredients must fall into place, creating a narrative emerges ellen van der wal, architect composition, contrast and complexity. a building must be put together and form a harmonious whole. when people look at it, it must have an effect on them. they must think something is happening here. initially, the functionality and durability. but the building must also be tempted. i try my buildings bring more contrast and composition sergio herman, chef cook beauty is in second place, the taste is most important. but other cooking i turn quickly to the appearance of taste. because testing starts with the eyes. when people see something, they expect something. we work with dinner plates of designers. i put down the court so that it follows the shape of the plate. iris van herpen, fashion designer balance. something must not be perfect, there must be some tolerance, because it stimulates people. if the viewer with my dress perceive a certain feeling, it has beauty i try to achieve that balance by such traditional techniques with those of today. this creates a balance between tradition and 'now' piet oudolf, garden and landscape designer perception, aesthetics and dynamics. beauty goes beyond the first impression, it's much deeper. if you see something, you should feel something coherence, the proportions must be correct. when is everything correct? if anything annoys you. it does not necessarily have to be perfect, even in imperfection can put things right table . overview of statement about beauty made by dutch designers noteworthy is that almost all designers consider formal property as a condition for experiencing beauty. and the consequence that there is a certain emotion to be felt. below the cited mentioned design principles per design discipline are put in an overview. design principles design discipline aspects of design goals starting-points and other aspects architecture balance, equilibrium, symmetry, sequence, rhythm, as well as order and complexity cohesion, unity, proportion, simplicity, density, regularity, economy, homogeneity prototypically usefulness, affordable, attracting attention form follows function form follows meaning threefold: utilitas (functionality), venustas (aesthetics) and firmitas (construction and sustainable) product design curiosità (curiosity) , dimostrazione (demonstration), sensazione (sensational), sfumato (gradient), attention, relevance, confidence and satisfaction useful form follows function form follows emotion form follows meaning pleasantness, responsibility, certainly, part | literature study on organizational aesthetics | aesthetics design principles design discipline aspects of design goals starting-points and other aspects arte/scienza (artistic / scientific), corporalita (corporality / human), connessione (connection) balance, symmetry, sequence, rhythm, unity in variety, proportion, simplicity, prototypically attentional activity, effort and situational control innovative, aesthetic, understandable, unobtrusive, honest, long- lasting, thorough, environmental-friendly, as little design as possible the maximum effect for minimum means, unity in variety, most advanced, yet accepted (maya) and congruency / appropriateness ict and multi media design balance, equilibrium, symmetry, sequence, rhythm, as well as order and complexity cohesion, unity, proportion, simplicity, density, regularity, economy, homogeneity fulfill human needs and to support human values support autonomy, promote creation and representation, optimal challenge, provide timely and positive feedback, facilitate human-human interaction, represents human social bond, facilitate one’s desire to influence others, induce positive and intended emotions what, why and how visceral, behavioural and reflective garden and landscape design directionality (static- dynamic, vertical- horizontal, straight- curved, regular-irregular, axiality), sequential relationships (repetition, contrast, rhythm, similarity, continuity), spatial relationships (shape, centralized- decentralized), symmetry- asymmetry, open-closed, height-to-width ratio, built-natural elements), solids and voids relationships (density, sensory qualities (human- monumental scale, balance-imbalance, light- darkness, color, texture), collative properties (surprise, novelty, mystery, ambiguity, puzzlingness, legibility, complexity) , anthropomorphic properties (human qualities) denotative meanings (convention, exemplification of use, style and structure) and commutative meanings (resemblance, symbolization, allusion, evocation) part | literature study on organizational aesthetics | aesthetics design principles design discipline aspects of design goals starting-points and other aspects predominant rise, punctuation, proximity), and overall organizational properties (unity, diversity) dance motif, repetition, variation and contrast, climax or highlights, proportion and balance, transition, logical development and unity literature identification (with storyline, emotions and characters) learning table . overview used design principles of in several design disciplines for organization design, what can be learned from design principles of architecture, garden and landscape design and product design? first, looking back on the mentioned design principles of the different design disciplines, can be observed that these are quite similar, in particular the interpretation of the formal properties like balance and harmony. together, the found design principles show are combinations of formal properties with starting-points and design purposes like supporting challenge or usefulness. functional beauty particular for above discussed most design disciplines is the almost natural combination of functional value and aesthetic value. here, the aspect of functional beauty is relevant. recent literature on aesthetics again argues the aspect of ‘functional beauty’ (fb) which considers both judgments, the ethical and the aesthetical. an organizationcan be good as an aesthetic object and good as a organization, but this need not mean classifying it first in one way, then in another. nor need it be a matter of evaluating the organization with respect to purposes other than its primary functional one. instead, the evaluation can focus on how the organization’s aesthetic qualities are relevant to and take account of its functioning as a good organization. than, questions can be tried to answer like whether an ugly organization can be good (high functionality), whether a beautiful organization is a good organization too and vice versa. in other words, they can be judged on functional beauty (and dysfunctional ugliness). the object of this judgment in this dissertation is the organization. both the aesthetic judgment and an overall functional evaluation of the organization have the same object, but the aesthetic judgment has a narrower focus. in making the aesthetic judgment, we consider if and how its aesthetic features enhance the organization’s functioning as a organization. is it beautiful in a functional way? whereas in arriving at the wider comprehensive evaluation, we take account of all that is relevant to how well the organizations functions as a organization. fb distinguishes at least two ways in which function can be related to beauty: external and internal (sauchelli, ). ´externalist accounts of fb usually establish the connection between function and beauty in the following logic. they start with the idea that there are objects which are clearly part | literature study on organizational aesthetics | aesthetics functional (i.e. buildings, cars, or furniture) and clearly possess aesthetic value. thus, an fb externalist advocates that functional considerations are relevant for judging an object aesthetically, because in cases where the object at issue has a specific function, it is necessary for such an object to fulfil its function in order to be judged as beautiful´ (ibid). an internalist theory of fb denies that functional considerations contribute to aesthetic judgments only negatively or indirectly. ´an internalist theory of fb is not committed to the strong thesis that beauty is to be explained solely in terms of utility´ (davies, ). ´more specifically, theories of this type suggest that an object can also be judged as beautiful by virtue of the way it looks in relation to its function (sauchelli, ). in other words, something can be judged as functional beautiful when one or more of its (positive) aesthetic properties contributes to the fulfilment of its function. according to this kind of theory, the concept of fb can be understood as a case in which beauty is literally functional´ (ibid). for organizations, initially it seems that the internalist theory of fb is most applicable. current literature on organizational aesthetics suggests stimuli in organizations like image, processes, decision- making and physical space of the organizationin which experienced beauty is literally functional. affordance-based design reflecting on above discussed design disciplines, they all recognize the added value of aesthetic experiences for the user. particularly product design and architecture, that both distinguish functionality from aesthetics. and both design disciplines perish a changing assignment for designers. form follows function has been changed to form follows meaning and value. or actually, material en production techniques as well as user requirements have lead to an extension of the traditional function of products and buildings. this change could be strongly related to the aspect of affordance, which was already touched at the section about garden en environmental design. gibson introduced the term ‘affordance’ which refers to what an environment offers in terms of the possibilities to perform activities and fulfill needs. according to gibson, ´affordance precedes subjectivity, interpretation, use, and meaning´ (almquist and lupton, ). gibson was most concerned with how animals perceive their environment, which he argues ´is through the perception of affordances in the environment´. ‘the affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill’ he stated. later, norman (norman, ) took gibson’s theory of affordances and extended it into a prescriptive formulation for human interaction. he defines affordance as the “perceived and actual properties of the thing, primarily those fundamental properties that determine just how the thing could possibly be used´ (ibid). he distinguishes ‘perceived affordances’ and he claims that ‘they result from the mental interpretation of things, based on our past knowledge and experience applied to our perception of the things about us’. later other authors have also begun using the concept of affordance within engineering design, architecture and industrial design research (maier and fadel, ). ´theories of use, usability, and users have grown out of the fields of engineering, cognitive science, and design research, and have been heavily influenced by norman’s notions of affordance (or perceived affordance)´, almquist and lupton argues. in order to express the use of an artifact, a designer aims to make explicit specific affordances by intentionally embedding cues for people who use the object. vyas et al. ( ) advocate that ‘the design process exhibits an interactive nature in order to support meaning-based actions of the design-participants’. this means that design should primarily be considered as a process of cognitive construction. meaning-making is considered as the process of constructing ways of interaction with the environment. they claim that ‘aesthetically-oriented emotions, which are the content of aesthetic experience, provide us the ability to assign values to those dynamic presuppositions of interaction enhancing the detection of interactive affordances.’ part | literature study on organizational aesthetics | aesthetics zhang and patel ( ) propose a framework for categorization of affordances which contain biological affordance (based on biological processes: e.g. a healthy mushroom affords nutrition, while a toxic mushroom affords dying), physical affordance (mainly constrained by physical structures: e.g. the flat horizontal panel on a door can only be pushed), perceptual affordance (provided by spatial mappings: e.g. if the switches of the stovetop burners have the same spatial layout as the burners themselves, the switches provide affordances for controlling the burners), cognitive affordance (provided by cultural conventions: e.g. for traffic lights, red means "stop", yellow means” prepare to stop", and green means "go"). many affordances are provided by a combination of more than one module. therefore zhang and patel distinguish mixed affordance. they refer to the ‘mailbox’ example given by gibson. ´a mailbox does not provide the affordance of mailing letters for a person who has no knowledge about postal systems. knowledge (cognitive affordance) and structure of a mailbox(physical affordance) are both involved in constructing the affordance for mailing and receiving letters´. for architecture, this movement can be considered as an attempt to provide appropriate form and function has been recognized by vitruvius who distinguished form (firmitas) and function (utilitas) were considered separate, but competing requirements, among others, such as beauty (venustas). maier and fadel ( ) suggest that ‘the concept of affordance could be used as a conceptual basis to unite the originally separate vitruvian ideas of form and function’. they mention some examples of the aspect of affordance in architecture. ‘buildings have many high-level affordances, including affording shelter to occupants from the exterior environment, affording aesthetics to occupants and passers-by, affording storage of goods, affording comfort to occupants through climate control, etc. more detailed affordances can better be analyzed by looking at specific building elements’ they argue. ‘individual properties of either the artifact (color, density, size, etc.) or the user (strength, age, height, etc.) are not in and of themselves affordances, but taken together can determine whether a specific affordance exists, such as the ability of a specific person to walk on a specific floor.’ almquist and lupton establish strong relationship with the possible expansion of traditional usability and utility of things. ‘for design researchers in the social sciences’ they argue, ‘utility is the essential question, namely “how things work and the degree to which designs serve practical purposes and provide affordances or capabilities,” while significance tends to describe a secondary set of acquired features: “how forms assume meaning in the ways they are used, or the roles and meaning assigned to them, often becoming powerful symbols or icons in patterns of habit and ritual’. ´in conspicuous consumption´ they continue, ´the manifest function is “the satisfaction of the needs for which these goods are explicitly designed” and the latent function is the “heightening or reaffirmation of social status.´ according to them, ‘functional analysis is an appropriate framework to analyze designed artifacts, because while designers may have an intention related to how their work ought to be used or the niche it will fill in the lives of users, objects frequently take on additional roles and have unintended consequences’. therefore they emphasize, that it is important to note that designed artifacts have multiple potential latent functions. ´these latent functions, moreover, can also be conceived as latent meanings, understood both subjectively (the personal associations with an object that accrue over time) and intersubjectively (as part of cultural complexes of value and significance that require communities for their activation). thus the “function” of conspicuous consumption unfolds as a primarily meaning-making activity, by which a consumer flags, brands, and publicly performs his or her place in the status landscape, which is also an object landscape´ (almquist and lupton, ). some researchers transferred the affordance approach to organization design. vyas et al. ( ) consider affordance as a ‘product’ or ‘result’ of human actions. ‘this fact refers to the dynamic and evolving nature of affordances’, they argue. ‘it allows designers to understand not only what is given to the users but also the experience and values that are supported by their designed part | literature study on organizational aesthetics | aesthetics artifacts.’ second, they consider affordance as an enabler or encourager of social activity. as an example they mention affordance of a academic work environment ‘that also allows the members to share non-work related but highly sentimental news (e.g. announcing the birth of a new born child), personal achievements (e.g. best paper award), personal interests (e.g. favorite books, favourite conferences) to support social awareness.’ zammuto et al. ( ) argued that ‘our affordance are the results of the influence or intertwining of it and organizational features’. by using the affordance lens ‘their values for explaining organizational form and function comes from how they are enacted together’. one of the affordances they propose is visualizing entire work processes. in relation to this dissertation this suggestion can be adapted to visualizing coherence, identity, goal achievement and progress and interaction. and more recent for example sutherland ( ), following denora ( ), developed the theory of aesthetic reflexivity, based on affordance based thinking. according to sutherland ( ), ‘the aesthetic workspace is the opportunity to engage in reflexive, critical thinking afforded by the aesthetics of the context created around arts-based activities.’ he argues that three underlying processes that arts-based methodologies deliver in developing this kind of reflexivity: a) experiencing self and others, b) objectifying experience and c) associating experience. . conclusions ‘art aspires beauty, science aspires truth. art is creative and science is descriptive. art appeals to emotion and meaning, where science appeals to reason. ´convenient clichés segregates the arts from the sciences, expressing the widespread conviction that each would be contaminated through association with each other´ (elgin and goodman, ). does the field of aesthetics, examining art, prove the contrary? mothershill ( ) designates aesthetics as a ‘intellectual wasteland, and the fault lies with the aestheticians themselves, who have been insensitive to the variety and flexibility of the language of criticism and the use s to which it i put.’ ahlberg (citing engel, ) offers at least two reasons why analytical aesthetics provided so unsatisfied revenues. analytical philosophers believe that philosophy like science is a common enterprise, and that therefore philosophical theses are discussable and criticizable. and second, analytical philosophers are convinced that here are can be progress in philosophy, although not in the same sense as in science. shusterman ( ) who looked back on the analytic aesthetics for many years concludes that ‘it seems likely that analytic aesthetics will move in a more pragmatist and activist direction, especially since critical practice has taken some surprising new paths which most analytic theorists will not wish to follow or accept as critical paradigms to which analysis as accurate second/order reflection must be faithful.’ so, studying the field of aesthetics ends unsatisfied and without usable insights? no, looking through the eyelashes at organizations, there are some. and more important, the main research questions of this part of the literature study can be all answered. the main conclusions about aesthetics are: aesthetic experiences are perceived in or attributed by aesthetic properties in objects and artifacts: the formal properties (harmony, balance, tension, etc.) for structuring, the representational ´properties´ (symbolic value, history, values, etc.)for identification and the expressive or sensory properties (color, sound, etc) for attention. several types of aesthetic experiences can be distinguished: cognitive (intellectual), perceptual, emotional and transcendental, moral, religious and sexual experiences. part | literature study on organizational aesthetics | aesthetics the probability of a positive aesthetic judgments and positive emotion - and less negative aesthetic judgments and less negative emotion - increases in proportion as the object, artifact or event contains more aesthetic properties. aesthetic properties supervene on non-aesthetic properties. the antecedents of experiencing aesthetics can be divided into personal characteristics (sensibility, mood, education, culture, age, interests, experience), characteristics of the object or artifact (the degree of aesthetic properties) and environmental characteristics (time to perceive, presence of other stimuli, the aesthetic process globally starts with observation. via interpretation and report the perceiver will come to aesthetic judgment and (aesthetic) emotion people’s awareness of the aesthetic quality of their environment and improving this aesthetic quality, can be influenced by working on the several aspects defined within the ontology of the aesthetic quality of objects. to stay out of the discussion of taste, while this is people and organization related, in any case the aesthetic quality of objects can be improved by working on the primary or formal and expressive qualities of objects and artifacts. assuming that these qualities forcefully supervene on the non-aesthetic properties of work and organizations. working on the secondary qualities of objects are probably related to organization values and identity. it is quite reasonable that aesthetic processes within organization will take place too; these will be experienced under more or less the same environmental conditions like a safe environment, a specific context, scale, time (period of maturation), with less social activity (derivation) and relation with other different objects; the aesthetic experiencing process results in an aesthetic judgment and an emotion as well. they can be positive (positive aesthetic experiences: paes) and negative (negative aesthetic experiences: naes). pleasantness, joyfulness and meaning are often mentioned emotions related to aesthetic experiences; during aesthetic processes, some psychological mechanisms should be taken into account like aesthetic induction, prototyping, familiarity; the design principles of many design disciplines (except organization design) can be considered as user-centered. examples are usefulness, affordable, understandable, unobtrusive, honest, long-lasting and environmental-friendly; the design principles of many design disciplines (except organization design) include aesthetic aspects for realizing aesthetic value for the user (design based on values, needs, functions and properties. part | literature study on organizational aesthetics | aesthetics reflection i will end this literature study on aesthetics with a personal reflection. plunge into the field of aesthetics gives me finally some unsatisfied feeling. i was educated or actually formed as a product designer. and i learned - during a design process as reflection-in-action (schön, ) - that products have functional as aesthetic value as well. designs were judged on the functional and only the formal or substantive aspects of the design like harmony, proportion and unity. the representative and expressive aspects (style, color) of the design were granted as taste of the designer and weren’t discussed or judged at all. working with formal or substantive aspects of a design is in the nature of a designer, i think. and this isn’t discussed by designers intensively or in a way aestheticians do. it’s just part of their job. i grasped the building blocks i need for design organizations. therefore i am thankful to the aestheticians. but let’s go on by citing zangwill ( ): ´there is a limit set to reasoning about aesthetic matters. we must ultimately look or listen, and feel.´ part | literature study on organizational aesthetics | aesthetics part | literature study on organizational aesthetics | organizations and design organizations and design this thesis is about the role of aesthetics in work and organizations. before liberating and embedding aesthetics in organization design and in design principles, this chapter will try to describe the basics of organization design and developments in organizations, the characteristics of professional organizations and the few contributions on aesthetics in organizations. in sum, the following paragraphs will be discussed: . current opinions on organization design . changing perspectives on organizations and management . job design and process design . professional organizations; . aesthetic perspective on organizations: a. design thinking in organizations; b. organizational aesthetics. . conclusions . organization design views on organization design in order to discover and embed aesthetics in work and in organizations, the building blocks of an organization need to be defined. certainly, aesthetic properties supervene on non-aesthetic properties (zemach, ; parker, ; sibley, ; zangwill, ; scruton, ). but, what are the oas? before trying to answer this challenging question, defining what a organization is and need to be done first. galbraith ( ) described the possibilities of organization design. ‘organization design’, he says, ‘is conceived to be a decision process to bring out coherence between goals or purposes for which the organizations exists, the pattern of division of labor and interunit coordination and the people who will do the work’. so, the design of the organizations must show coherence between strategy, organizing mode and integrating individuals. galbraith discusses the different approaches on organizations which their own views on organization design. the classical school considers the organization design as a triangle of structure and reward system. the human relations approach on organizations adds information and decision process to it. whereas the people perspective on organization design distinguishes task, structure, information and decision processes, reward systems and people as the basic ingredients of an organization. gerstein ( ) defines organization design as ’the configuration owned and ‘virtual’ business capabilities, the structuring of reporting relationships and administrative units; the engineering of operating, management and information systems; and the fostering of the organization’s different ‘cultures’ to enable it various constituencies to accomplish their respective objectives’. according to van aken ( ) a design is ‘a model of an object to be realized, made as an instruction for the next step in the creation process. a designer should at least and preferably only specify in his/her design what the people, who are to realize it, need to know in order to realize it as intended by the designer’. part | literature study on organizational aesthetics | organizations and design parameters for organization design scott and davies ( ) mention the essential six ingredients of an organization based on nadler and tushman’s congruence framework ( ), which are: environment, strategy and goals, work and technology, formal and informal organization and people. they criticize this framework because ‘it tends to perpetuate the dualism that distinguishes structure, whether formal or informal, from people and their actions’. and second, they think ‘the entire framework is highly static, privileging elements and structures over actions and processes.’ for overcome these limitations in this ‘theory of structuration’, they succeed giddens’ approach. he argues that ‘organizations comprise social structures which consist of rules and schemas (models for behavior) and resources (both material and human) which acquire their meaning and value form the schema applicable to them’. rather than focusing on a stable , static, cross-sectional view of an organization structure, ‘it reminds us to consider the ways in which moment by moment, day by day, and year by year, structures are undergoing transformation, thereby providing new and different opportunities for individuals making choices and taking action’, according to scott and davies. thus, according to them, organizations must have some other ingredients which the call capacities. they cite hannan and carroll ( ) who proposes three capacities: durable, reliable and accountable. based on these assumptions they propose three definitions of an organization, based on the rational, natural and open system perspectives: ‘organizations are collectivities oriented to the pursuit of relatively specific goals and exhibiting relatively highly formalized social structures (a rational system definition); organizations are collectivities whose participants are pursuing multiple interests, both disparate and common, but who recognize the value of perpetuating the organization as an important resource (a natural system definition); organizations are congeries of interdependent flows and activities linking shifting coalitions of participants embedded in wider material-resource and institutional environments’. they describe rational, natural and open systems as perspectives or paradigms, because organizations ‘do not deal with a single unified model of organizations structure, but rather with a number of varying approaches that bear a strong family resemblance’. galbraith ( ) stated that ‘organization design is conceived to be a decision process to bring about coherence (which is a formal aesthetic property) between the goals of or purposes for which the organization exists, the patterns of division of lobar and inter-unit coordination and the people who will do the work’. jonker et al. (jonker et al., )conclude (citing scott, ) that ‘despite the abundance of organization design theories no general principles applicable to organization design in all times and places can be identified’. they suggest that ‘first a formal representation of an organizational model as a design object description should be provided. in addition to this, to address the operations performed on such design object description during a design process, a formal representation of design operators underlying possible design steps is needed.’ they conclude that ‘often in the literature organization design is recognized as an engineering problem’ (citing child, ). from this perspective design they considered this as ‘a continuous process of a gradual change of an organizational model by applying certain operations’ (pfeffer ). minzberg ( ) describes the design process as the following sequence of operations: ) given overall organizational needs, a designer refines the needs into specific tasks, which are further combined into positions: ) build the "superstructure" by performing unit grouping using special guidelines and heuristics (e.g., grouping by knowledge and skill, by work process and function, by time, by place, etc.); ) grouping process is repeated recursively, until the organization hierarchy is complete. referring to the mentioned formal aesthetic properties, grouping, repetition and coherence seems to be - at least in theory - advised principles in organization design. part | literature study on organizational aesthetics | organizations and design hatchuel ( ) concludes that design is not a well established concept in the organizational literature. he argues that ‘classical organization theory is the infant of bureaucratic theory and the latter is the infant of the representation theory of things. if standards, outputs, or skills are given, or adequately represented, then they act as the contingent variables of organization theory. he notes that yet, design theorists in architecture and art has strongly considered organizational and social settings in their thinking’. he notices that the literatures about organizing and organizational forms have been based on concepts that directly belong to the language and grammar of design theory. ‘the traditional organizational chart is in itself a designed artifact’, he states. it is well known, according to hatchuel, ‘that design theory takes its roots in the history of architecture, art and engineering. it has taken more recently an increasing importance in the thinking of simon ( ) in the field of management science. design theory is a central issue in the disciplines that are oriented to some form of ‘arte’ in its old latin meaning of ‘the making of some thing’. hatchuel thereafter formulated five propositions which will align organizational theory with design theory: proposition : innovation, artistic work, cultural activities are activities which have design theory and work as a major component, stake and conflictual area. and several findings of the literature on these issues can be reinterpreted as confirmations of these hypothesis. proposition : the alternate to bureaucraties can be theorized as design-oriented organizations . proposition : in design oriented organizations the power cannot be exerted only by allocating resources or arbitrating between conflicting orientations. power lays in the ability to influence the design work by creating concepts, changing design processes, activating different forms of knowledge. proposition : project management and knowledge management has been the most popular mottos in management in the last decade. in spite of being extremely simplistic forms of design theory, they can be also interpreted as evidence in favor of the extension of design- oriented organizations. proposition : co-design is the most difficult form of cooperation between different companies. proposition . the organizational identity of firms is recognizable through the nature of their design activities. although jonker et al. ( ) stated that ‘it is widely recognized in social studies that no ‘best’ design of an organization exists, a number of informal guidelines and best practices developed in the area of organization design can help in identifying the most suitable organization designs’. to overcome the lack of general principles applicable to organization design, they suggest to use ‘abstraction grammars and hierarchical graph grammars, based on a set of ten design operators which provides the means for creating a design of an organization from scratch as well as revising existing designs for organizations: . organization: by the patterns of relationships or activities in an organization, and described by sets of roles, groups, interaction and interaction links, relations between them and an environment; . organization structure: a structural description of an organizational specification described by the relation is determined by a set of atomic relations; . organization dynamics; . roles: representing a subset of functionalities, performed by an organization, abstracted from specific agents (or actors) who fulfill them. each role has an input and an output interface, which facilitate the interaction (communication) with other roles part | literature study on organizational aesthetics | organizations and design . ontology mapping: the ontology, which describe interfaces of interacting roles, can be different. therefore, if necessary, the specification of a role interaction process includes ontology mapping; . interactions; . interlevels: an inter level link connects a composite role with one of its sub roles. it represents an information transition between two adjacent aggregation levels. it may describe an ontology mapping for representing mechanisms of information abstraction; . group: a group is a composite structural element of an organization that consists of a number of roles. in contrast to roles a group does not have well-defined input and output interfaces. groups can be used for modeling units of organic organizations, which are characterized by loosely defined or sometimes informal frequently changing structures that operate in a dynamic environment. furthermore, groups can be used at the intermediate design steps for identifying a collection of roles, which may be further transformed into a composite role; . environment: the conceptualized environment represents a special component of an organization model. according to some sociological theories (e.g., contingency theory), an environment represents a key determinant in organization design, upon which an organizational model is contingent. similarly to roles, the environment is represented in this proposal by an element having input and output interfaces, which facilitate in interaction with roles of an organization. the interfaces are conceptualized by the environment interaction (input and output) ontology; . dynamic property.’ organization configurations and models by investigating the aspects of organization design, mintzberg must be mentioned because of his groundbreaking work he did on this topic. mintzberg ( ) reviews nine different parameters used in organizational design. they are divided into four different groups: ) individual position design parameters (job specialization, behavior formalization, training and indoctrination), ) superstructure design parameters (unit grouping, grouped by market or by function and unit size), ) lateral structuring parameters (planning and control systems and liaison devices) and ) decision making parameters (planning and control systems, liaison devices and decentralization). he also described five configurations of organizations: the simple structure, the machine bureaucracy, the professional bureaucracy, the divisionalized form and the adhocracy. because this dissertation particularly concerns about professional or knowledge-intensive organizations, the characteristics of the professional bureaucracy and the adhocracy seems to be most relevant. in a professional bureaucracy the work performed by the operating core becomes so complex that only the workers themselves fully understands its contents, they gain more control over the actual work processes (mintzberg, ). according to mintzberg, ‘this configuration is characterized by coordination by standardization of skills, and is in effect the only organizational structure that allows standardization and decentralization to coexist. the standardization is closely related to the training and indoctrination exerted on the employees, and therefore largely lies outside the control of the organization itself. this type of organization emphasizes the power of expertise and this is also one of its strongest technological assets. the use, and limitations, of expertise is called pigeonholing the problem at hand. this follows when the professionals work requires performing two basic tasks, first to categorize what the client needs and choose which template solutions its the situation best, and then next to execute the chosen program.’ the adhocracy, mintzberg notes, ‘characterizes an organization with a dynamic environment and that deals with problems that the organization profits from solving are complex. the organizational structure has to be both very flexible and adaptive. knowledge and skills are required to solve tasks, which because of their complexity often spans several problem domains. therefore information is very part | literature study on organizational aesthetics | organizations and design valuable, and an uninterrupted flow of it, is crucial in ensuring the optimal solution. a adhocracy needs a very organic structure with very little behavior formalization. jobs are highly specialized horizontally, and the employees are professionals.’ many models for organization design have been developed the last centuries, all more or less based on the above mentioned approaches and models. gavrea ( ) examined in her phd-dissertation about the use of most common organizational models for organizational diagnosis and for improving firm performance. these are: force field analysis, the leavitt’s model, weisbord's six box model, galbraith's star model, nadler and tushman's congruence model, mckinsey's -s model, the ‘four quadrants’ of bolman and deal, burke-litwin model and freedman’s swamp model. she concludes that these models have both common and distinctive features. ‘the most obvious features of these are: . the vast majority of the organizational diagnostic models presented are based on open systems theory, therefore the external environment is presented as a separate category that influence the way organizations operate in five of the nine models. . most models illustrated a number of variables that are in a relationship of interdependence. the most obvious example of this ´cause and effect´ relationship is the burke-litwin model. models which do not express an interdependent relationship are: weisbord's six box model and bolman's four quadrants. . the model with the fewest variables is the leavitt's model which includes variables and the model with the most variables is burke-litwin model containing variables. the remaining models indicate about - variables. the key variables in these models can be divided into two categories: those defined in general terms such as force field analysis and those based on well-defined theoretical foundations such as the congruence model. . these models have a number of common variables, but with different importance in different models. . a single model of organizational diagnosis includes performance as a separate variable (e.g. burke-litwin model).’ she also claimed that the most used models in practice proved to be weisbord's six box model ( % of companies analyzed, used as a basis for organizational diagnosis this model) followed by -s model ( %) and third star model and nadler and tushman's congruence model ( %). all the above models are models that address organizations as open systems. earlier burke and litwin ( ) examined the relationship between organizational models and performance. like gavrea ( ), they reflected on the most used organizational model and concluded that ‘these models (especially the -s model and weisbord’s six-box mode) evolved from practice.’ they believe that ‘these models have valid components because they are in fact based on practice and do not convey irrelevant or the so-called ivory tower thinking’. the -s model identifies seven dimensions of organizations: shared values, strategy, structure, staff, systems, skills, and style (waterman et al., ; pascale and athos, ). an important starting-point of this model is that it reduces complexity by identifying the main ‘levers’ of organizations. however, although each lever is of greatest importance, the different levers cannot be treated independently. ‘the central point is that the fit among and between them has to be good to get long-term leverage’ (pascale and athos, , italic in original): they are interdependent. changing one of them affects the whole system. according to burke and litwin the strengths of the -s model are ) its description of organizational variables that convey obvious importance / strategy, structure, systems, style, staff, skills and shared values and b) its recognition of the importance of the interrelationships among all of these seven variables, or dimensions. weggeman ( , ) developed an european variant of the model, called the esh-model. this part | literature study on organizational aesthetics | organizations and design model identifies strategy, management style, systems, personnel, culture and structure as the main organizational dimensions. the model stresses that the organizational factors refer to both intended and unintended, formal and informal, measurable and non-measurable, implicit and explicit, internal and external determined aspects. esh stands for balance, coherence and heterogeneity (translated from dutch: evenwicht, samenhang en heterogeniteit). with 'cohesion' is meant that any change in one of the elements also can or will result in a change in the other five elements. it means that each element is equally important. so, coherence in this perspective expresses something else than is distinguished in literature on aesthetics. consistent coordination between the six elements and a balanced distribution of time and energy on those elements is required. a third characteristic is heterogeneity in the sense that the model expresses both formal and informal dimensions. concluding, more and more organization theory and design theory will be aligned. organization design in future more and more will take into account cultural aspects and will respond to needs of employees. the esh model (based on the -s model) seems to be a useful model for applying organizational aesthetics. it is proved in practice proved and contains valid components. views on designing organizations although uncovering and embedding aesthetics into the organization design doesn’t mean redesigning organizations, it is necessary to have insights in the process of designing organizations. chandler ( ) introduced the thought of ‘structure follows strategy’. which means that ‘different organizational forms result from different types of growth can be stated more precisely if the planning and carrying out of such growth is considered a strategy. the organization devised to administer these enlarged activities and resources, a structure. the thesis thus is that structure follows strategy.’ according to gerstein ( ), ‘the organization designer’s job is to select the least-managerially demanding organization that best fits the ‘design criteria’ appropriate to the situation and strategy.’ therefore he distinguishes six phases in the organization design process, which are: . clarify the purpose of the organizational redesign, articulating the design criteria to be used to contrast and compare design alternatives. consider overall change management requirements in view of the nature and scale of the redesign being undertaken. . analyze the industry and company value chains to develop an understanding of the business’ fundamental processes, basic economics and risks, and potential alternative foundations for competitive advantage. . identify and evaluate alternative configurations of “strategic components”, focusing on those parts of the value chain that should be conventionally owned vs. those that should be provided through partnership, supply, and outsourcing arrangements. decide on the nature of the macrostructure and other arrangements required to achieve the necessary coordination between separate organizations. . generate specific “design options” for one’s own organization, including the overall organizational architecture, major processes, fundamental information technology infrastructure, structural grouping and linking mechanisms, etc. include external organizations as well as internal ones within the scope of the design to ensure necessary horizontal integration. . identify additional requirements to achieve overall objectives in areas such as performance measurement and reward, staffing and selection, knowledge leverage, organizational culture, and leadership. part | literature study on organizational aesthetics | organizations and design . identify implementation issues, such as managing the approval process, planning the communications/roll out logistics, overcoming specific sources of resistance, and so forth. minzberg ( ) describes the design process as the following sequence of operations:’ given overall organizational needs, a designer refines the needs into specific tasks, which are further combined into positions’. uncovering and embedding aesthetics into the organization design seems to be strong related to phase and possibly phase . romme and endenburg ( ) suggest a science-based approach to organization design which includes the five components of organization science, construction principles, design propositions or rules, organization design and implementation and experimentation. ‘a construction principle emphasizes the importance of a certain type of solution in view of certain values or goals (e.g. ´to achieve a, do b´), while design interventions or rules elaborate solution-oriented guidelines for the design process (e.g. ‘if condition c is present, to achieve a, do b’). construction principles outline the deeper meanings and intentions behind design rules’ (ibid). zhang ( ) agrees, but distinguishes design principles from design guidelines. ‘design principles are high-level and largely context-free design goals’, he argues. ‘while design guidelines are narrowly focused, specific and context- dependent rules for designers to follow’. lekanne deprez and tissen ( ) state that ‘designing is a fundamental process and not a repair job’. one way to start such a design process is to consider an organization as a system. they cite stanford ( ), who summarized five models (mckinsey -s model, gailbraith’s star model, weissbord six box model, nadler and tushman congruence model and burke-litwin model) that serve as a framework to envision the organization in a holistic way. they conclude that ‘although these models have been tested over at least two decades, each one was developed in an era of relative stability when organizations tended to have a single overarching design. today’s and tomorrow’s world is different. so the models, even if updated, ‘pertain to an industrial economy (and even early service economy)’, according to lekanne deprez and tissen. boonstra ( ) argues that ‘the design-approach seems suitable when the problem is known, not too complex, and a solution is within reach. the approach is mandatory when the organization is in crisis and rapid action is needed. also, when no reasonable degree of consensus about the nature of the proposed change can be reached, or a sizable reduction in personnel is expected, a design-approach seems more appropriate. the develop-approach appears more suitable with complex issues where the solution is not directly evident. the develop-approach is preferable when improvements and innovations can be effectuated gradually and incrementally, and value is set on an enhancement of the organization's ability to innovate’. boonstra suggests a integration of both approaches by using search-conferences, participative design, and democratic dialogue methods which are used in the contemporary development approach (e.g. mohrman and cummings, ; axelrod, ; weisbord, ). for realizing this new way of ‘developing designing’, five barriers to change need to overcome: ‘a linear and formal process of decision making on redesign; the existing division of labor and poor inter-functional teamwork; the existing culture, norms and values limiting people’s ability to change; the existing power configuration; top-down management of the change process and poor vertical communication’, according to boonstra. part | literature study on organizational aesthetics | organizations and design table . overview differences design approach and development approach (boonstra, ) thus, the process of designing organizations should start with the question of what the purpose is of the organization redesign, taking into account the needs of the organization. it may be assumed that the change of form follows function into form follows meaning affects the approach of values in organizations. starting from improvements based on the existing organization, a development approach instead of a design approach seems to be more effective. . changing perspectives on organizations and management this dissertation starts with assumption that aesthetics is missing in the current perspective on organization design. following roozenburg and eekels ( ), the design of the organization needs to change as a consequence of changing roles and needs of the employees in this case. assuming that when needs and values of employees, like sense making, meaning, experiencing aesthetics, are changing, considering that properties can fulfill one or more functions, and by fulfilling functions a design satisfies needs that gives people the possibility to realize one or more values, also the properties will have to change as well. guillén ( ) argues in his famous article ‘scientific management’s lost aesthetic’ that ´a numerous studies have identified scientific management with a highly constraining, overtly exploitative and ideologically conservative model of organizations´. scientific management, according to guillén, ´has been portrayed as a paradigm of reckless deskilling, impersonal production and mediocre quality, which appears to be at odds with artistic creation and recreation´. ´the aesthetic message of scientific management has received virtually no attention from organizational researchers’, he concludes. guillén studied european avant-garde modernists, especially architects, who worked with the principle of unity, order and purity, which should be ought to guide any design. ´the european architects and designers turned the mechanical into a metaphor for beauty and form as well as function´, he concludes. ´they found in scientific management a lost sense of the beautiful that has escaped the attention of the field of organizational studies´. end he ends his article with the conclusion that ´we have long neglected the aesthetic context of organizational behavior´. peters ( ) agreed with guillén and suggest attention for aspects like elegant, warm, coherence, simple and graceful beauty as a response to the scientific management movement. hatchuel ( ) tries to link organization theory and design theory. his argumentation for this attempt is because of his observation that ‘classical organization theory is the infant of bureaucratic theory and the latter is the infant of the ‘representation theory of things’. ‘if standards, outputs, or skills are given, or adequately ´represented´ then they act as the contingent variables of organization part | literature study on organizational aesthetics | organizations and design theory´, he argues. he discusses ´the mintzberg typology´, what he called ´the bureaucratic model´, in which design is supposed to be there active and efficient: how it works, how it changes was not considered. ´the bureaucratic model could change only through a new design theory´, he states. ´one of the pitfalls of post-taylorian and post-fordist literature is that they have analyzed changes at the level of the assembly worker or at the operations level as if job enrichment or even participative work was significant of a major shift. the real long term changes were not there and were going to take place in design work and designer’s collective activities, those places and workers not analyzed in the bureaucratic model´, he agues. linking organization theory and design theory leads to a theoretical position rather unusual: organizational theory reaches appearance of autonomy only in the special case of the bureaucracy where precisely design is assumed but not discussed; design theory reaches appearance of autonomy only in the special case of bureaucracy and or market relations where designers have an authoritative position; in all other cases, design theory and organization theory are contingently interrelated, hence are not autonomous fields, hatchuel concludes. therefore, hatchuel proposes a new type of organization, the ‘design oriented organization’ (do ). he defines design oriented organizations as: organizations were the central resources and efforts towards change are concentrated on design activities; design oriented organizations can also be defined more theoretically as organizations which have the capability to organize collective design in a context of great concept- knowledge distance (c-k distance). for designing or reforming organizations to design oriented organizations, he foresees four ‘logics of actions’: . ´establish a genealogy of things and contexts that will serve as a knowledge reference for say ‘the flying boat’: this means building reference worlds to the ‘new concept ‘: all sort of methods can be use here. . choose a design space (material and symbolic) where the identity of a ‘flying boat’ and some of its assumed features can be expressed and used as a first validation process: it is most likely that some drawings could be the design space here ; yet it is not always the case: in engineering the design space could be a computational model ; and in other cases it could directly a mock-up, or a hardware circuit. . define a memorizing process where lessons about the design process can be kept: naming, labeling, recording experiences are necessary techniques to vizibilize the new ‘things’ coming to being. . prescribing an organizational kernel like a first special group of experts and plan for a revision process of this first kernel´ (hatchuel, ) cairns ( ) observed tendencies in a range of literature on managerial approaches. the main tendencies he notices are organizational cohesion (pettigrew and whipp, ), shared vision (wack, ; collins and porras, ; cohen, ) and the exercise of leadership to seek to transform followers into a more unified and motivated body (bass, ). according to cairns, ‘such approaches involve a drive for uniform meaning and interpretation across all organizational actors. such approaches often ignore the essential contribution to meaning and understanding of what is omitted from any situation, with sole concentration on what is present, or on what is acknowledged as present – relevant for inclusion according to the particular model of analysis’, he argues. part | literature study on organizational aesthetics | organizations and design ‘given the dramatic changes taking place in society, the economy, and technology, st-century organizations need to engage in new, more spontaneous, and more innovative ways of managing.’, this is how adler ( ) starts her article about the arts and leadership. according to her, ‘the twenty- first century society yearns for a leadership of possibility, a leadership based more on hope, aspiration, and innovation than on the replication of historical patterns of constrained pragmatism.’ she cites austin, a harvard business professor, who says that “the economy of the future will be about creating value and appropriate forms, and no one knows more about the processes for doing that than artists’. one of the trends she experiences, is ‘yearning for significance, success is no longer enough’. she cites hamel ( ) who states: ‘what we need is not an economy of hands or heads, but an economy of hearts. every employee should feel that he or she is contributing to something that will actually make a genuine and positive difference in the lives of customers and colleagues. for too many employees, the return on emotional equity is close to zero. they have nothing to commit to other than the success of their own career. to succeed in the st century, a company must give its members a reason to bring all of their humanity to work.´ according to adler, the time is right for the cross- fertilization of the arts and leadership: ´the very essence of st-century leadership increasingly demands the passionate creativity of artists´. pine and gilmore ( ) identify five principles for creating ‘experience environments’. geursen ( ) adds to a total of seven principles that experience concepts meaningful and distinctive and possess stamina. these seven principles are: ) theme (what's the story?), ) identity (which is ambiguous and subjective construct?), ) authenticity (shows the concept of a natural and authentic impression?), ) involve all the senses (be as many senses?), ) problems (adjust all elements within the context of the theme?), ) harmony (all variables are aligned?) and ) memory (the organization is aware that these 'memories makes?). witkin ( ) states that ‘the development of modern business and administrative organizations that are formally rational and technical in their structures and operations has given rise to the false conclusion that the aesthetic dimension does not figure at all in their making.’ taptiklis ( ) examined the current interpretation of management (‘managerialsm’) and distinguishes - also after reading bryan and joyce’s article about the st -century organizations ( ) - the following characteristics: ) lofty superiority (‘no trace of humility’); ) disdain for ordinary human intercourse (‘no time for the complexities, subtleties, and uncertainty of real human behavior or of real human relations’); ) blind optimism about the future, coupled with indifference to history; ) belief that productive human behaviors are always monetized and ) anti-humanity. rejecting this dominant way of managing, the storymaker project suggests five main opportunities to organizations that wish to outgrow the strictures of managerialism: . bring recorded narrative experience into the living present; . use the emergent properties of narrative experience to identify themes, patterns and learning pathways; . look for existing capabilities and emergent potentialities to help to determine organizational direction; . celebrate the ordinary and the everyday; . consider narrative practice as a moral source in its own right. lekanne deprez and tissen ( ) recently look back on organizations and conclude over the past thirty years that ‘many influential management thinkers and gurus (e.g. margreth wheatley, henry mintzberg, gareth morgan, arie de geus, tom peters, stan davis, jay galbraith and william starbuck) have largely come to accept – and to advocate - the idea that organizations are not machines; they are part | literature study on organizational aesthetics | organizations and design as unpredictable, unruly, self-organizing, and even responsive as any living beings. just as organizations will have to exist in less tangible, less prescribed forms, so will managerial thinking have to become less departmentalized, less silo – based and more open. the managerial mind set must make a fundamental shift beyond tweaking existing organizational forms and (re)mixes, to reinvent them into new ‘creations’.’ ‘order, closeness, and equilibrium (citing arthur, , and take into account as aesthetic properties,) as ways of organizing explanations are giving way to open-endedness, indeterminacy, and the emergence of perpetual novelty’, according to lekanne deprez and tissen. further on they state that ‘the overall aim of research into organizational (re-)design is generally to develop an accessible, robust body of knowledge that enhances the understanding of designing organizational configurations, processes, applications, methods and contexts to allow managers and employees to successfully create, transform and revitalize organizations for enduring performance’. according to them, ‘organization design is thus a broad and unfocused term that traditionally refers to the process of assessing and selecting the structure and formal system of power, communication, and division of labour, coordination, control, authority and responsibility required to achieve an organization’s goals’. dunbar and starbuck ( , cited by lekanne deprez and tissen, ) believe that ‘designing must be iterative, that design efforts must be persistent, and that designing and taking actions are intimately bound up with one another. but in the process of designing organizations, designers nearly always misunderstood the goals and scope of the project. therefore they should view their efforts as experiments that might not turn out to be predicted, and they should pay careful attention to the outcomes of these ‘experiments’. recently palmer, benveniste and dunford ( , cited by lekanne deprez and tissen, ) identified five areas where different assumptions concerning new organizational forms are in use, underpinned by a variety of theoretical perspectives: ( ) type of change represented in transferring to new organizational forms ( ) outcome of changing to new organizational forms; ( ) drivers for changing to new organizational forms; ( ) level of analysis associated with discussing new organizational forms; and ( ) meaning of new in new organizational forms. therefore, labeling an organizational form as ‘new’ in the st century can be a good starting point, but it requires close investigation and creative research effort. after looking back for thirty years, lekanne deprez and tissen ( ) suggest a new approach on organizations, especially knowledge based organizations, namely ´spatial organizations´, which follow the management perspective of ´what you do and how you do it´. however, they conclude, ´the dominant logic of the three step approach is far more mental than mechanical - i.e. based on vision and perspectives rather than applying standardized work methods, tools and processes. instead of managing for traditional performance through the structuring of work – of things, tasks and activities to do or not to do – performance can be organized through ‘arranging’ the minds of people and by bringing those people together who share the same – or similar - mental models.´ the three steps of the process towards the design of spatial arrangements they identified are dimensioning, orientating and formatting. dimensioning focuses on the question of how knowledge can be better applied and exploited in organization design. orientating involves the deployment of people of their minds towards the best use of knowledge. and third, formatting directs people’s attention on improving the productivity and quality of knowledge by imposing standardization and modularization on mental work activities as much as possible. according to them, ´these three steps of spatial organization design must be seen in relation to each other as a closed loop. dimensioning leads to orientating, orientating leads to formatting and back and forth. the process works as a roadmap, in part | literature study on organizational aesthetics | organizations and design which dimensioning results in a ‘mental map’ of the business landscape that works as a geography of space, the process of orientating as a compass for navigating through space and the process of formatting as a ‘drivers manual’ which adapts itself to different road conditions (‘business environments’). this process of organization design can still operate even when the original roadmap is incomplete.´ mcmillan ( ) considered organization structure and design from a complexity paradigm perspective. she argues that ‘the nature and importance of organization structure and the underpinning design principles are not well understood and yet play a key role in organizational performance’. citing pascale, milleman and gioja ( ): ‘design is the invisible hand that brings organizations to life and life to organizations.’ they also considered the role of architects and the principles the use to create buildings that provide structural integrity (sound buildings), functionality (space appropriate for its intense use) and aesthetic appeal. she suggests four new factors for organization design which are speed, flexibility, integration and innovation. for embedding these factors into new organizations, she proposed new design principles which are self organizing principles, complex adaptive systems, fractals, flow and rhythm and design of a speculative structural model. boonstra ( ) starts his contribution about organization design with his opinion about organizational form. ‘a suitable organization form is established by considering the characteristics of the organization's environment and the nature of the production process. from the perspective of socio- technical systems theory and business process redesign, it is argued that the functional structuring of organizations should be abandoned. for the enhancement of flexibility and customer orientation, attempts are made to design the organization on the basis of customer or product flows’. ‘within these flows teams are formed’, he stated. looking back on redesign-initiatives he concludes that many projects aimed at a redesign of organizations do not yield the desired outcomes. it is estimated that to % of the redesign projects in the united states fail (citing, davenport, ). then pascale, who published in his vision on organizations in the book ‘surfing on the edge of chaos’ (pascale et al., ), argues that business and nature share four fundamental ‘laws’: . equilibrium is death. when a living system is in a state of equilibrium, it is less responsive to changes taking place around it. . innovation usually takes place on the edge of chaos. in the face of threat or galvanized by an opportunity, living things move toward the edge of chaos - a condition in which experimentation is rampant, and new solutions are uncovered. . self-organization occurs naturally. as this experimentation and discovery is taking place, the components of the living systems self-organize, creating new forms that emerge from the turmoil. . living systems can only be disturbed, not directed. living systems can't be directed along a linear path. unforeseen circumstances are always going to appear. the best approach is to "disturb" the system in the direction of the desired outcome. for embedding these laws these in organizations, a design perspective, according to pascale et al. could be an fruitful method (‘design, don't engineer; discover, don't dictate; decipher, don't presuppose’). galpin et al ( ) stated - after examining business schools’ mba programs, business literature and proceeding a management survey - that ‘functionality is still the prevailing, present-day organization design, business education continues to be functionally focused, management literature has part | literature study on organizational aesthetics | organizations and design emphasized functionality, and managers still manage functionality’. they conclude that ‘even though our data identified several factors that reinforce the continued prevalence of functional organization structures, organizational performance appears to be an aspect that would support the use of cross- functional designs’. therefore, galpin et al. recommend several strategies that need to be pursued much more vigorously to create connected, cross-functional organizations: . within organizations, management needs to design structures around the customer. customers want a single point of contact for multiple, typically cross-functional, services. . implement cross-functional work designs. modular, team-oriented production systems require employees and managers who produce and problem solve from a multi-faceted perspective. . deliver cross-functional communications. organizations need to frequently communicate about cross-functional topics such as customer centered issues, cross-functional problems that have been solved, and multi-disciplinary activities. . eliminate old rules and policies that reinforced functional thinking and behaviors. replace them with new rules and policies which support cross-functional views and actions. . replace functional ceremonies and events, such as departmental meetings and awards functions, with cross-functional (e.g. process- or company-wide) events. ‘creating a cross-functional organization’, they argue, ‘is not merely a ‘pay issue’, a ‘training issue’ or even a ‘design issue’. the solution is a coordinated, multi-faceted approach to designing, implementing, and reinforcing cross-functional organization structures’. hasan et al. ( ) notice a need for sense-making in organizations, based on arguments weick, wiley and cecez-kecmanovic and jerran, ‘in the face of the increased complexity and rate of change in the social and commercial context of their operations and in order to maintain a strategic and sustainable position in the broader society’. they suggest ‘a sensible organization that needs to be understood in the context of its structural and functional form, and the interdependencies between these, in shaping the organization’. avital et al. ( ) introduce the ‘positive lens’ on organizations after concluding that ‘it is time, for considering management as a design discipline and for re-balancing the pendulum toward´ what herbert simon described as the ‘design face’ of management.’ they agree with boland and collopy (boland and collopy, ) who argued that ‘who propose ‘a fresh view of management that is much more creative, graphic, artistic, collaborative, and visionary than the familiar and oversimplified ‘decision face’ of management.’ ‘designing information and organizations with a positive lens brings subsequently two highly diverse communities of scholarship together to ask’ (ibid), they argue. ‘can designers’ ways of knowing, relating, and being expand our current models and theories of appreciative inquiry’ (avital et al., )? and, the authors ask themselves: ‘can appreciative ways of knowing, relating, and being expand the potentials of those studying in the fields of design?’. they answer these questions by suggesting three reasons for adopting a positive lens on organizing: . ‘joining a positive lens on organizing with the transformative power of design thinking opens new horizons and possibilities for creating organizational and social well-being. the positive lens applied to information and organization design opens broader considerations of social context, uses cross-disciplinary tools, takes a holistic approach, and emphasizes a responsible, ethical attention to human possibilities. . taking a systemic view, the chapters in this volume demonstrate that organizations and their information systems are inextricably coupled and that to study one without the other would part | literature study on organizational aesthetics | organizations and design be myopic. it is hard to imagine organization without information, and it is equally unlikely that information and its technologies could have developed as they have without the support of organizations that embrace them as central to their existence. . the vocabularies of appreciative inquiry and design have much in common and draw us toward a view of the world that is open to endless possibility. for example, in appreciative inquiry the world is seen not as a problem to be solved, but as a mystery to be embraced and, in designers’ ways of knowing, the world is seen as an opportunity to imagine, improvise, prototype, experiment, and play with ‘all the materials we have all around us.’ (avital et al., , p. ). in both domains, they underpin, ‘there is a sense in which valuing what gives life brings something new into the world. in both domains, there is a keen appreciation of questions such as ‘‘how might we …?’’ and of our human capacity to create new realities.’ whitney’s ( ) contribution about life affirming organizations starts with the question ‘what gives life to human organizing?’ after concluding that images and ideals of organization design have changed dramatically in the past decade. she states that’ successful businesses have adapted their organizations to social innovations such as global access to information; enhanced diversity and connectivity among members, consumers and customers; the desire of people world wide for participation in decisions that affect their lives; and increasing opportunities for doing business globally.’ and after mentioning google and semco as examples of innovative and liberating organizations which are draw upon people’s strengths and their desire to excel, and care about and focus upon what gives life to people, communities and the environment, value health and vitality in the ways they do business, in their products and services, and in their organization designs, she introduces a new genre of organizations: life affirming organizations. whitney states: ‘in nature we recognize the differing degrees of life in a breaking wave, a mountain stream and a pond of industrial waste. in social life we sense differing degrees of life in a lovers embrace, a handshake with a new customer and an icy stare. all organizations and human collectivities, conversationally, materially and spiritually possess some degree of life. most significantly, the quality of life creates an organizational consciousness which people can feel and describe when they experience it.’ according to her, thus, ‘there is recognizable life in all things, a series of questions then arises. what is it that gives life to human organizing? what makes one organization more life affirming and sustaining than another? what gives vitality to social collectivities?’ according to whitney, a preliminary answer to these questions is found in nine principles of appreciative organizing. ‘they are thoughts about what gives life to human organizations and communities, based on thirty years of experience working with and observing hundreds of organizations. and indirectly, they offer ideas for designing life affirming, appreciative organizations’. these nine principles of appreciative organizing are: . evolutionary purpose; . harmonious wholeness; . appreciative leadership; . positive emotional climate; . strong centers of meaning; . just in time structures; . liberation economics; . engaged participation; . caring culture. part | literature study on organizational aesthetics | organizations and design after arguing that ‘organization design is the reconsideration of everything, from the ground up, so as to shape a living society inside a dying society’, she suggested six facets of ‘appreciative organizing’: artifacts and technology, relational processes, relationships, communication, language, and consciousness. ‘these facets reflect the intersection and application to organizations of my interests and long history with communication theory, social construction theory and consciousness studies. they range from those that are material and tangible to those that are relational and sensory apparent to those that are subtle and less readily apparent as a structure of reality. each of these facets is interrelated and is influenced by and influences the others’, according to whitney. so, in her opinion, ‘organization design is about embedding values in processes, conversations, artifacts and action with profound attention to social aesthetics, relational integrity and systemic implications for life. the nine principles of appreciative organizing are value based. they value life in all forms of expression, the gifts and potential of each person, freedom of speech, and the right to participate in decisions impacting your life. they value work as a noble endeavor and business as a powerful force in society. they value cooperation, social justice, the celebration of diversity and mindfulness in the pursuit of happiness’, she ends her contribution. zandee ( ) argues in this same journal the role of appreciative inquiry by using poetics in organization design. ‘through the narrative mode of knowing, we give meaning to our lived experience. we discover what might be possible in organizational life through embellished, contextual stories about particular, concrete events (citing tsoukas and hatch, )’, she states. ‘appreciative inquiry facilitates meaning making processes that enable the discovery of novelty and opportunity. metaphorical reframing is used to help participants look sideways at worn-out issues, or to create liberating punctuations in dysfunctional ways of thinking (citing barrett and cooperrider, ). metaphor is included in inquiry guiding questions to invite playful explorations of important aspects of organizational practice.’ zandee ( ) argues that groups now are able to reorganize and redesign the existing construct of stimuli in ways that will enable their organizations to realize new experiences. to focus these conversations, participants often use well-known frameworks of organization design such as the mckinsey -s model, or the weisbord -box model (watkins and mohr, ). for all of the selected design elements, participants write ‘provocative propositions’, which are statements ‘that describe some aspect of the desired organization as it ‘should be’ (citing barrett and fry, ).’ she describes the use of appreciative inquiry initiatives, where ‘groups are commonly guided through two successive phases of diverging and converging conversations.’ she notes that ‘they are first facilitated through a collaborative exploration of the best that exists in their past and present and an envisioning of their highest future aspirations. these explorative conversations are followed by discussions that focus on the creation of an organization design for the desired future, and the planning for activities that will enable and sustain movement in the direction agreed upon.’ the poetic design principles she proposes (imaginative, ambiguous, touching and holistic) ‘stand in sharp contrast with design principles such as efficiency and expediency’, she argues. but are needed ‘for having a imaginary thought’, like mentioned in the literature about design thinking. ‘poetic, rather than logic-pragmatic, design principles’ she states , ‘may guide vibrant ways of organizing that can enable provocative possibilities for a more sustainable and just global society. informed by the special qualities of poetic language, we may be able to create organizations that ‘sing’ rather than just ‘work’ (citing barry and rerup, ).’ also neilsen ( ) made the ´positive shift´ by positing ‘that a new form of organization has been emerging, what one might call positive organization. in contrast to traditional bureaucracy, he argues, ‘positive organization is based on members’ commitment to the development of supportive and sensitive relationships with each other, bolstered by shared norms and values, and to focusing attention on mutual education, win/win objectives and strategies for achieving them.’ part | literature study on organizational aesthetics | organizations and design a positive organization is an adaptive response to emerging environmental conditions. for operationalizing this, neilsen proposes two strategies. ‘one strategy of course is to allow ecological forces to do their work, to wit, over time organizations that adopt more positive forms are more likely to survive while those that do not will die out.’ and second, ‘embedding the design process in a matrix of interpersonal activities that heightens the designers’ experience of secure attachments with each other and with the organization.’ according to neilsen, ‘the characterization of secure attachments as the cornerstone of positive organization suggests in turn that the modern design activities can benefit from interpersonal settings where secure attachments are actively promoted.’ he suggest that two strategies reveal different ways of doing this. first, appreciative inquiry starts with interviews that rekindle participants’ most positive organizational experiences. second, ‘the subsequent juxtaposition of new designs, based on those positive experiences, against current realities, leads to the identification of gaps that may represent major challenges and emotional discomfort’, according to neilsen. bryan and joyce ( ) earlier described the ‘ st -century organization’ after concluding that companies do very little to enhance the productivity of their professionals. the state that ‘their vertically structures, retrofitted with ad hoc and matrix overlays, nearly always make professional work more complex and inefficient.’ according to bryan and joyce, ‘companies must design a new model holistically, using new principles that take into account the way professionals create value.’ therefore they suggest four interrelated organization design principles: . streamlining and simplifying vertical and line-management but also structures by discarding failed matrix and ad hoc approaches and narrowing the scope of the line manager’s role to the creation of current earnings; . deploying off-line teams to discover new wealth-creating opportunities while using a dynamic- management process to resolve short- and long-term trade-offs; . developing knowledge marketplaces, talent marketplaces, and formal networks to stimulate the creation and exchange of intangibles; . relying on measurements of performance rather than supervision to get the most from self- directed professionals. zandee and broekhuijsen ( ) consider that ‘something is shifting in the terrain of management and organization. confronted with a troubled financial system and a global recession, the question arises whether a swift repair of our existing institutions will be sufficient to weather the storm.’ and they continue: ‘those of us who believe in reform rather than repair, realize that we need new ways of seeing and thinking in order to find creative solutions for the problems that were caused by our modernist approaches to business and organizing. this explains the current thrust to balance our dominant analytical way of knowing and the prevalent questions of efficiency and expediency with more artful considerations of management (adler, )and organization design (weggeman et al., ; yoo et al., ). in efforts to heighten the vitality and agility of organizations and the innovative and improvisational qualities of management, many in the field of organization studies seek inspiration from artistic endeavors such as architecture, theatre and jazz (zandee, ,).’ they offer a new organizational perspective, based on a ‘theatrical rehearsal as relational form giving process’. they suggest some specific organizing principles which are: responsiveness: rehearsing is about interaction. the performance created through the rehearsing process is the visible manifestation of the interactions sparked among a unique combination of individuals with specific resources working together in certain circumstances. each individual action needs to be an effective response to the prior gestures of others while at the same time making a new contribution to the overall texture and direction of the play; workability: acting means action. one can observe this clearly during rehearsal, where a passive intellectual mode of “talking about” what could be done is avoided and replaced by an part | literature study on organizational aesthetics | organizations and design active mode of doing what might work. the focus of the cast and its director is on the workability of the multiple possibilities for each component – such as characters, movement, props, and set design – that together will enable the performance. guided by the question what will work best, actors try out their ideas in a series of alternative gestures. unsettledness: during rehearsal, director and actors strive to maintain complexity and openness as long as possible to delay the moment when things become “fixed” in chosen forms. the ability to keep the creative flow going and to welcome chaos and unsettledness, allows for the emergence and appreciation of perhaps surprising acting possibilities that may eventually be selected for performance; embodiment: theatre is the bodying forth of meanings contained in texts which depict certain aspects, conflicts or dilemmas of our human and social existence. it gives those meanings a visible, physical form. acting, like music making or dancing, is an essentially bodily activity (zandee and broekhuijsen, ). according to zandee and broekhuijsen, ‘the four congruent principles which give the rehearsal its form giving capability and relational texture enable the design of organizational rehearsal spaces in which the idea of designing as a process of artful making can be explored. managers, according to them, become artful directors of change when they consciously create and facilitate organizational rehearsal spaces around the principles of responsiveness, workability, unsettledness and embodiment. working together in such spaces people can utilize their sensuous, imaginative and relational capacities in order to give form to novel solutions that not only work but are also beautiful and enjoyable.’ van dienst ( ) argued in his dissertation that ‘towards technical or economic progress is a certain longing for the past, compared artificiality is natural, far carried out towards differentiation and integration unit, compared rationality is such an aesthetic experience, facing economic system comes to nature.’ after studying the several perspectives on ‘new organizations’ can be concluded that even the leading thinkers about organization design don’t come up with a unanimous opinion on organization design in future. in an overview: lost sense of the beautiful (guillén, ; witkin, ) narrative experience use the emergent properties (taptiklis, ) experience concept (pine and gilmore, ) spatial: less departmentalized, less silo – based and more open (‘arranging’ the minds of people and by bringing those people together who share the same – or similar - mental models´) (lekanne deprez and tissen, ) speed, flexibility, integration and innovation through self organizing principles, complex adaptive systems, fractals, flow and rhythm (mcmillan, ) participative design, and democratic dialogue (boonstra, ) responsive, self-organization, design thinking (pascale et al. ) cross-functional, designing, coordinated, multi-faceted approach (galpin et al., ) sensible organization: sense-making (hasan et al., ; guillet de monthouw, ) positive lens on organizations: appreciative, management as a design discipline, (avital et al., ) life affirming organizations: appreciative organizing (whitney, ) holistically, creating value (bryan and joyce, ; zandee, ) theatrical rehearsal as relational form giving process: sensuous, imaginative and relational (zandee and broekhuijsen, ) design thinking, collective work, improvisation (e.g. hatchuel, ) part | literature study on organizational aesthetics | organizations and design do these many perspectives have something in common? yes, new organizations seem to care about people, in which appreciating and holistic values, meaning and design thinking have an important role as well. all suggested features of ‘new organizations’ can be regarded as a motivational perspective on design, like zhang ( ) supports. this perspective explains human’s various needs, the relationship among psychological needs, states attribution, and environmental factors and their impact on goal-oriented commitments. the purpose of (re)design than is to positively supports employees’ motivational needs like emotional needs (emotion and affects). this perspective seems to build on the socio-technical approach, suggested by boonstra ( ), which was developed after research on work conditions of british miners by trist and bamforth ( ) of the tavistock institute of human relations in london (van eijnaten, ). a "social-technical system" within an "open" system-view is the central starting point of this perspective. a socio-technical system is formed by a technical and a social subsystem, which are depending of each other because they both need to fulfill the production function. in the ‘ s, the perspective was translated (e.g. by hackman and oldham, ) into several organization principles, such as optimum variety of tasks within the job; optimum length of work cycle, providing 'interlocking' tasks, job rotation on physical proximity, and inputs should be monitored as carefully as outputs (e.g. pasmore, ; van eijnaten, ). referring to the next section, mentioned intrinsic work motivation of professionals, requested values and needs of ‘modern employees’ (professionals) are still changing. being consequent with the argument and the design causality of roozenburg and eekels ( ), properties and functions, the organization design, must change when needs and values of employees are changing. professional organizations, based on the overview above, must change for creating value to professionals because their needs are changing. they want to learn and get intellectually challenged and only want to get busy with their profession. the only thing they want (their needs) from their organization is getting conditions for doing professional work. this changing function of the organization will have consequences for the properties of the professional organization. this will be discussed later. part | literature study on organizational aesthetics | organizations and design . job design and process design during the field research of this dissertation, respondents will ask to register their daily aesthetics experiences. these aesthetics experiences probably will be a mix of experiences triggered by oas as well as by aesthetic stimuli in events, their work activities. this distinction divides aesthetics experiences related to aspects of organizational design, job design and process design. job design job design or work design is concerned with the content of the job that an individual or group undertakes, i.e. the roles and tasks they fulfill, as well as the methods that they use to complete their work (holman, clegg and waterson, ; birnbaum and somers, ; mohrman, ). system (re)design is concerned with the design of the entire department or organization. a main theoretical approach is that of the characteristics of jobs and this has been strongly influenced by the work of hackman and oldham ( ) and their job characteristic model. this model is the most widely applied and dominant approach for research on job design and work outcomes (morgeson and champion, ; parker and wall, ). hackman and oldham suggest that three psychological states (experienced meaningfulness, responsibility, and knowledge of results) are necessary for high levels of work quality and propose that five core job dimensions are instrumental in producing these psychological states. these job dimensions are skill and task variety, task identity, task significance, autonomy, and job- based feedback. task variety is related to the fact that completing repetitive tasks offers no challenges to employees and can cause them to lose interest and become dissatisfied. task identity suggests that employees are more satisfied when they have an opportunity to complete a ‘whole’ piece of work (goal achievement). task significance suggests that employees need to feel responsible for their work and understand the significance of their work and how it impacts on other. autonomy is the employee’s control of their individual work. and feedback suggests that employees need information on how they are doing otherwise there is no satisfaction from performing effectively. once the three psychological states are activated, work motivation, job satisfaction, and work performance should improve. experiencing meaningfulness especially will occur when skill and task variety, task identity and task significance are activated. they further suggested that these outcomes would be more significant for employees with high growth needs, like professionals. the goal of this model is to design work so that it will be personally satisfying and intrinsically rewarding. a second well spread theory is the two-factor theory of herzberg and colleagues (herzberg et al., ). they distinguish two types of factors, namely motivators (intrinsic to the work itself like achievement, recognition and responsibility) and hygiene factors (extrinsic to the work like work conditions, pay and supervision). according to herzberg’s theory, ‘only a challenging job has the opportunity for achievement, recognition, advancement and growth that will motivate personnel.’ parker et al. ( ) developed an elaborated model of work design that distinguishes five categories of variables, namely antecedents (like management style and organizational design), work characteristics (like skill variety and team autonomy), outcomes (like affective reactions, and customer satisfaction), mechanisms (like learning and development) and contingencies (like interdependence and goals clarity). they suggest that ‘work design cannot be seen as an isolated construct but should be considered as two dimensional: considering the different types of factors (such as antecedents and outcomes) and the individual, group and organization level of analysis’. part | literature study on organizational aesthetics | organizations and design process design process design can be considered as a linkage between organization design and job and work design. this linkage is discussed because literature on organizational aesthetics also distinguishes the aspect of process aesthetics (e.g. strati, ; alvesson and berg, ; taylor and hansen, ). process (re) design was embraced by the ‘camps’ total quality management (tqm), business process redesign (bpr) and the ‘eclectic approach’ to the radical design of business processes (smith, ) at the ‘ s of last century because of three challenge (rummler et al., ): ) to articulate and organize work so that it can be effectively and efficiently performed; ) to articulate and organize work so that it can be effectively managed and ; ) it offers potential for a competitive advantage. they define a process as ‘a chain of activities that convert s various inputs to various outputs’. ‘process orientation (po) means focusing on business processes ranging from customer to customer instead of placing emphasis on functional and hierarchical structures (reijers, ). po emphasizes process as opposed to hierarchies with special focus on outcomes, particularly customer satisfaction’ (mccormack and johnson, , cited by kohlbacher, ). a process-oriented organization comprehensively applies the concept of business process management (bpm). ‘a firm which adopted the process-view of its organization, regardless of whether it has already run through business process reengineering (bpr) and/or process improvement projects or not, is concerned with the management of its business processes’ (kohlbacher, ). according to him, ‘bpm does not only incorporate the discovery, design, deployment, and execution of business processes, but also interaction, control, analysis, and optimization of processes.´ . professional organizations this dissertation concerns about aesthetic experiences in organizations, particularly in professional organizations. this special type of organization, inhabited by professionals, needs to be explained. since etzioni ( ), alvesson ( ), galbraith ( ), bell ( ) and later drucker ( ) suggested that powerful new class of technical-scientific experts was emerging and that knowledge is a central feature of a post-industrial society, terms as knowledge work, knowledge workers, knowledge organizations and knowledge management are nowadays widely popular (el-farr, ; blacker, ). drucker ( ) even mentioned that ‘a shit is occurring in the relationship between knowledge and wealth creation’ and ‘a society is emerging that is dependent upon the development and application of new knowledge’ (‘knowledge is being applied to knowledge itself’). bryan and joyce ( ) estimated in that % of employees in us industry performed knowledge intensive work. the european commission speaks about % of the workers in europe in could be considered as knowledge workers. both the practical and the theoretical implications of drucker’s thesis are significant, blacker ( ) argued. ‘just as the nature of organization and management changed dramatically at the time of industrial revolution and later as a result of taylorism, drucker maintains that new approaches are now becoming necessary. productivity is becoming dependent on the application and development of new knowledge, and on the contributions of specialist knowledge workers. drucker's thesis is that knowledge workers are unlike previous generations of workers, not only in the high levels of education they have obtained, but principally because, in knowledge-based organizations, they own the organization's means of production (i.e. knowledge). drucker suggested that, in these circumstances, familiar images of organizations as hierarchical, decentralized or as a matrix should be discarded’ (blacker, ). mintzberg obviously had such thoughts while he developed the professional bureaucracy and the adhocracy like explained before as appropriate configurations for professional organizations. let’s go more in detail to the work (design) and characteristics of knowledge workers part | literature study on organizational aesthetics | organizations and design and professionals. according to davenport et al. ( ), professionals (‘high-end knowledge workers’: hekw’s), ‘control their own work structure, they are highly collaborative, work in multi settings, individual as well in groups and have high levels of passion, power and occupational mobility´. davenport ( ) later claimed that ‘knowledge workers as employees with high degrees of expertise, education or experience and the primary purpose of their jobs involves the creation, distribution, or application of knowledge’. according to winslow and bramer ( ), ‘knowledge work is about ‘creating solutions for problems within organizations, through interpreting and applying information, and thus support and recommend them to the firm’s management’. reich ( ) claimed that knowledge workers have ´special skills identified in three: problem solving; such as research, product design and fabrication; problem identification, such as marketing, advertising, and customer consulting; and brokerage, such as financing, searching and contracting.´ shapero ( ) defined the work of professionals as customization, improvising, visionary, knowledge- intensive, little routine, custom, difficult words and autonomous. later he added another important attribute of professional work. it is not immediately definable and measurable in terms of output. ‘the output, but the process is ever changing and also different for each professional. it is also said that professionals are not comparable. but the characteristics of a good performance barely definable, assessable and be valued by others than ‘colleague-professionals’. despres and hiltrop ( ) illuminate six elements that make knowledge work different from other work: ´ ) the career formation of knowledge workers is dependent on socialization, education and interaction with external factors; ) their loyalty is for the profession, peers, and network. this is due to the nature of work they perform, for they highly depend on networking and social structure to acquire, learn, coordinate, share, identify problems, help others, build awareness, produce, and verify their knowledge work; )’ knowledge work tasks are specialized, deep and often diffused with the external network; ) the work is mostly produced at the group level, with a focus on customers, problems and issues; ) a great attention should be given to obsolescence of skills, in order to add, remove or alter existing ones. knowledge workers should be in a continuous state of learning, sharing, unlearning, and relearning and ) sixth, knowledge workers’ feedback and activity systems are lengthily, relative to other occupations.’ and more recent jackson ( ) distinguishes other specific aspects for designing job design for professionals, which are accountability, empowerment, knowledge, self-efficacy, interdependence, emotional identity, and social identity. as with any approach to change, job redesign has a set of fundamental principles, she argues. these are system alignment and organizational support, learning and development, participatory approach and respect and valuing. ‘system alignment and organizational support is concerning the redesign should integrate with organizational structure and processes (stebbins and shani, ), objectives and the goals of the job redesign. it requires the availability of support, resources, and information to support decision making and problem solving as well as to enhance accountability for outcomes’. so, job redesign requires attention to both formal and informal effective communication strategies between professionals and managers. related to learning and development, ‘the job redesign should include and promote opportunities for new knowledge generation, application and dissemination’ (stebbins and shani, ). ‘it emphasizes the need for continuing personal and professional development and lifelong learning’ (gunderson, ). ‘comprehensive training programs will need to be considered, in particular, decision making processes related to coordination of care and accountability for care’ (ibid). ‘respect and valuing in job design should be completed by encouraging and empowering professionals part | literature study on organizational aesthetics | organizations and design to act on their knowledge and expert judgment’ (laschinger and wong, ). ‘the newly designed job needs to allow for continuous performance feedback and recognition’ (tonges et al, ). overlooking all these characteristics of knowledge work and knowledge workers, some more implications for the organization in which knowledge workers perform – especially about the design principles - can be made. drucker ( ) argued that ‘to attain knowledge workers’ loyalty, productivity and motivation, they need different compensation structures, management and leadership styles, and complementary organizational structure and processes’. he emphasized intrinsic rewards to be more effective in motivating knowledge workers while others suggested a well balanced combination of intrinsic and extrinsic ones. some highlighted the importance of group-level compensations to increase interaction, while others found a combination of individual, group and organizational rewards as best serving the motivation of knowledge workers (el-farr, ; taylor, ; siemsen and balasubramanian et al., ; yahya and goh, ; maister, ). as for the managerial and leadership styles, they claimed to emphasize social networks, internal and external, in addition to promoting the social structure, self-management, and soft control rather than concentrating on work flows and tasks (el-farr, ). ‘specialists cannot en don’t need to be told how to do their work’, drucker ( ) stated. therefore drucker ( ) advised managers to develop rewards, recognition, and career opportunities, to create unified and shared vision (‘a view on the whole’), to devise the management structure for an organization of task forces and to ensure the supply, preparation, and testing of top management people. ‘leaders are recommended to encourage self-learning, knowledge sharing, knowledge production, knowledge acquisition, knowledge creation, and self-development of employees. freedom (autonomy) from the traditional authority is claimed to reinforce employees’ creativity and mobility’. as for structures, they are viewed as more effective if they offer more flexibility and less hierarchy (‘flat’) (e.g. drucker, ; maister, ; maccoby, ; el-farr, ). ‘organizational processes are recommended to continuously change, making the knowledge workers’ work more productive and focused, in addition to minimizing their stress and increasing interaction. occupations contain both knowledge work and routine operations. it is suggested that knowledge work should be emphasized while routine operation should be automated with less organizational processes or simpler and more flexible ones’ (el-farr, ). davenport ( ) argued that ‘management should realize that if they want to enhance the productivity of their organization’s knowledge workers then they should identify each group of them separately and accordingly specify the needed interventions. this is due to his realization that knowledge workers are not homogenous due to different levels of routinized tasks, interaction, judgment, and complexity of work’. morhman ( ) argued the aspects of work design of professionals. she appoints five specific design requirements for this typical environment: work designs are dynamic, work is designed for collaboration, work designs focus on the larger system and local performance and work is designed for learning. part | literature study on organizational aesthetics | organizations and design referring to the earlier distinguished design parameters of an organizations, in overview these for professional organizations are summed up below (based on davenport et al, ; weggeman, ). design parameters interpretation for professional organizations strategy hire good people and leave them alone structure flat, flexibility and less hierarchy (task groups) stimulating innovation, efficiency and customer intimacy style self-management, promoting learning collective ambition and shared values staff loyalty to discipline systems focus on input and output dual and triple ladder (t-ladder) for development personal commitment statement (pcs) skills sensemaking dual and triple ladder (t-ladder) for development facilitating learning by socializing table . design parameters of professional organizations part | literature study on organizational aesthetics | organizations and design . aesthetic perspective on organizations before reflecting on current literature on organizational aesthetics, first another quite new organization area will be discussed, which is design thinking. . . design thinking in organizations design principles in other design disciplines were noticed at the end of the previous century by researchers and authors about organization design. simon ( ) can be seen as the bridge-maker between traditional design and organizations. in his book ‘the sciences of the artificial’ he argues that ‘many professionals are undertaken design as a daily activity’. in his view, design is as a rational set of procedures in response to a well-defined problem in which solving it involves decomposing systems, searching for and choosing alternatives, and that this also worked for ill-defined or wicked problems. simon describes a logic of design. a so called ‘optimization methods’ in which ‘shoulds’, shalts’ and ‘oughts’ will argued. ‘a decision attitude carries with it default representation of the problem being faced, whereas a design attitude begins by questioning the way the problem is represented’ (boland and collopy, ). ‘this logic of optimization can be sketched as follows: the ‘inner environment’ of the design problem is represented by a set of given alternatives of action. the alternatives may be given in extenso: more commonly the are specified in terms of command variables that have defined problems. the ‘outer environment’ is represented by a set of parameters, which may be known with certainty or only in terms of a probability distribution. the goals for adaption of inner to outer environment are defined by a utility function – a function, usually scalar, of the command variables and environmental parameters – perhaps supplemented by a number of constraints (inequalities, say, between functions of the command variables and environmental parameters). the optimization problem is to find an admissible set of values of the command variables compatible with the constraints, that maximize the utility function for the given values of the environmental parameters (maximize the expected value of the utility function)’. boland and collopy continue: ‘first, design is concerned with how things ought to be, with devising artifacts to attain goals. design does not give answers to whether something exists, but whether logics are need for, or even useful for design. second, the logic of design is about finding alternatives. not the realize an optimum design, but a satisfactory design: of all possible worlds (those attainable for some admissible values of the action variables), which is the best (yield the highest value of the criterion function)?’ boland and collopy ( ) edited the book ‘managing as designing’ in which they give an overview of the aspects of design which possibly can be transferred to organizations. they believe that ‘if managers adopted a design attitude, the world of business would be different and better. managers would approach problems with a sensibility ‘that swept in the broadest array of influences to shape inspiring and energizing design for products, services, and processes that are both profitable and humanly satisfying.’ they relate decision making with designing and conclude that ‘the design attitude towards problem solving, assume that it is difficult to design a good alternative, but once you have developed a truly great one, the decision about which alternative to select become trivial.’ a design attitude views each project as an opportunity for invention. designers relish the lack of predetermined outcomes and looks for the real thing we are trying to accomplish, unvarnished by the residue of years of organizational habit, according to them. a good design is one that is more satisfying in more ways that any available. also weick ( ) contributed to this remarkable book. he concludes that ‘if managers keep imposing machine metaphors and mechanistic assumptions onto events in an effort to stabilize them, predict them, and control them, then categories, stereotypes, schemas, routines, an formalization seem like useful tools. this is a pervasive scenario in organization design, clearly visible in contemporary part | literature study on organizational aesthetics | organizations and design command-and-control systems.’ design, weick argues, ´is a battle of sorts between naming the thing and losing the dream, and keeping the dream but losing the name that stirs others to make the dream happen. to reanimate designing, we need to move upward slowly, away from zones of focus toward the naming that begins to compound out abstractions.’ ‘if managers need to understand and coordinate variability, complexity, and effectiveness’, according to weick, ‘then the need to create design that mix together perceptual and conceptual modes of action or move back and forth between these modes or rely on multiple compounding of abstraction: designing that uses transient constructs, bricolage, and improvisation.’ tzonis ( ), in the same book, offers, like lekanne deprez and tissen ( ) do later, the perspective of spatial-figural organizations. this space-based type of representations, either through building metaphors of through diagrams, ‘appear to be particularly good in dealing with data concerning intriguing structures of sequencing, as one in complex schedules, or with overlap and inclusion, as in the case o multiple administrative responsibilities and controls.’ tzonis (like hanson, ) mentions sketches and morphological maps as useful methods for ‘systematically generating ideas by recombining precedents recruited by analogy.’ finally, orlikowski ( ), touches in the pioneering book of boland and collopy the aspect of ‘enacting reality’. according to orlikowski, designing is ‘to make representations of the world (‘representations of possible realities’). ‘managing is designing, as is evident in the discourse of management, which reflects a preoccupation with operating on the world through symbolic means.() it is like giving a form to an idea by shaping artifacts and events that create more desirable futures’. orlikowski argues, that ‘good designers are inspired to create artifacts (with commitment to co-create with others who will enact them in practice) that both exhibit an enduring aesthetic quality and generate outcomes in use that people care about. recognizing the constitutive role of enactment in design means seeing that ‘good design’ cannot be ascertained a priori; if by design we follow workshop organizers in meaning the creation of desirable futures. good design in this view is not an intrinsic feature, stable property , or static quality of the representation (the design artifact, building, program, organizations), but a recurrently enacted accomplishment provisionally and ongoingly achieved by human actors trying to use the design to get something useful done.’ thus, design thinking can be considered as the way designers think (dunne and martin, ). brown ( ) defines this thinking as ‘a methodology that imbues the full spectrum of innovation activities with a human-centered design ethos. a discipline that uses the designer’s sensibility and methods to match people’s needs with what is technologically feasible and what a viable business strategy can convert into customer value and market opportunity. it is the mental process they use to design objects, services or systems, as distinct from the end result of elegant and useful products. design thinking results from the nature of design work: a project-based work flow around ´wicked´ problems’. according to jones ( ), designing can be defined as ‘the initiation of change in man-made things’. jones examined traditional design methods of craftsmen and concluded that ‘the method of design- by-drawing is too simple for the growing complexity of the man-made world. the usual difficulty is that’, according to jones, ‘of losing control of the design situation once one is committed to a systematic procedure which seems to fit the problem less and less as designed proceeds. although the method of using scale drawing gives the designer the freedom to alter the shape of the product as a whole, instead of being tied, as the craftsmen is, to making only minor changes. scale drawing can be seen as a rapidly manipulable model of the relationship between the components of which a product is composed’. jones suggest that, because of the massive unsolved,’ problems that have been created by the use of man-made things like traffic congestion, parking problems, airport noise, new design methods are needed to resolve these problems and design solutions in the existence. one of the new methods he mentioned is designing with the use of hierarchy (‘vertical’ mode of designing) for instance a hierarchy of components on community, system, products and components level. is this hierarchy, also political and social aspects of human behavior is also involved. the challenge of part | literature study on organizational aesthetics | organizations and design designing alternative combinations of possible sub-components is that a sufficiently informed and sufficiently uninhibited person can select a promising set of sub-components in the first place’. another component of new design methods is , according to jones, the use of a design committee (within sponsors, design team, producers, users, society, etc.). according to lawson ( ) ‘a designer is primarily helping to create a future world, and in this sense his task is inevitably confounded by many doubts and uncertainties’. lawson distinguishes three what he called ‘basic discernible design approaches’ for deal with uncertainly, which are procrastination, von-committal design and throwaway design. ‘procrastination is based on the idea that somehow the future may become more certain if only we wait a little. if it is not possible to be sure of our actions now then maybe it will be easier to take a decision next year or the year after. a response of uncertainty is the non-committal design which have lead to bland, anonymous and neutral design’. the third approach is to design for the present only. ‘when the design isn’t sufficient anymore, a new design must be realized’. lawson also defined the most common design problems. ‘design problems cannot be comprehensively stated because of the uncertainties about the emerging objectives en priorities during the design process. design problems require subjective interpretation; designers likely to devise different solutions and they also perceive problems differently. and third, design problems tens to be organized hierarchically’. lawson argued that there is no objective or logical way to determining the right level on which to tackle problems. but he fortunately also suggests design solutions to overcome these design problems. according to lawson, ‘there are an inexhaustible number of different working solutions and there are no optimal solutions’. lawson especially examined the design process and proposed the riba plan of work map of the design process which can divided into the four phases of assimilation, general study, development and communication. he also cited the markus/waver map of the design process which distinguishes the phases of outline proposal, scheme design and detail design where each phase contains the steps of analysis, synthesis, appraisal and decision. according to lawson, ‘the design processes are endless, there is no infallibly correct process, the process involves findings as well as problem solving, the deign is inevitably involves subjective value judgment, design is a prescriptive activity and designer work in the context of a need for action’. hanson ( ) discuss the role of morphology in architectural design and mentions, like other design thinkers often did, schön’s ( ) influential account of the designer as a ‘reflective practitioner’. ‘the design process as reflection-in-action started from the premise that the fundamental condition of design is one of uncertainty, uniqueness and conflict. good design, he pointed out, has to take account of innumerable interacting factors and the consequences of ignoring any one variable could result in a catastrophic failure’, according to hanson. dunne and martin ( ) advocate the design thinking idea. they claim that ‘we are on the cusp of a design revolution in business. today’s business people don’t need to understand designers better they need to become designers.’ they believe that companies have to become more like ´design shops´ in their attitude and work methods. and have to change from traditional work patterns to a continuum along five dimensions: flow of work, life, style of work, mode of thinking, source of status and dominant attitude’. below, they distinguish the differences between traditional firms and ´design shops´. part | literature study on organizational aesthetics | organizations and design table . overview differences traditional firm and design shop (dunne and martin, ) dunne and martin consider that designers are models of people who can solve the most wicked problems through collaborative integrative thinking, suing abductive logic (kolko, ), which means the logic of what might be. conversely, deductive and inductive logic are the logic of what should be or what is. the idea of ´wicked´ problems was originally developed by rittell in the s (buchanan, ) and described a ´class of social system problems which are ill-formulated, where are the information is confusing, where there are many clients and decision makers with conflicting values, and where the ramifications in the whole system are thoroughly confusing’. according to dunne and martin, design thinking contains three aspects: cognitive, affective and interpersonal.’ the cognitive aspect of design thinking is about inductive, deductive and abductive thinking. abductive can be elucidated as the process of forming an explanatory hypothesis. here the designer knows both the value he/she wants to create, and the ‘how’ (the working principle or mechanism) that will help the value the design aims for. the ‘what’ that will give definition to the problem as well as to the potential solution can be sought (dorst, ). another type of abduction, abduction- , starts the solving problem process with only knowing the end value, for example aesthetic value, the designer wants to achieve. this need to establish the identity of ‘what’ and ‘how’ leads to design practices that are quit different from convential problem solving (abduction- ) (dorst, ). abduction is the only logical operation which introduces any new ideas, like designers use abduction to generate an idea, deduction to follow these ideas to their logical consequences and predict outcomes, and induction to generalize from the result’. design thinking, according to dunne and martin, therefore, ‘combines the generation of new ideas with their analysis and an evaluation of how they apply generally’. the attitudinal aspects of design thinking are explained by the example of the different way managers and designers experience problems. for conventional managers, constraints are seen as an undesirable barrier to the generation and implementation of ideas; designers, however, constraints are embraced as the impetus to creative solutions. finally, the interpersonal aspects of design thinking are about understanding users’ perspectives and their needs and by collaborating with peers. buchanan ( ) distinguishes four areas wherein design has a prominent role and plays affects contemporary life. first, the design of symbolic and visual communication, like the work of graphic design, book and magazine production and multi media. second, the design of material objects like clothing, domestic objects, tools, instruments, tools and machinery. the third area is the design of activities sand organized services, which includes the traditional management concern for logistics, combining physical resources, instrumentalities etc.. design thinking in this area, according to buchanan, ‘can contribute to achieving an organic flow of experience in concrete situations, making such experiences more intelligent, meaningful and satisfying’. and fourth is the area of complex systems or environment for living, working playing and learning. this includes the traditional concerns of system engineering, architecture and urban planning or the functional analysis of the parts of part | literature study on organizational aesthetics | organizations and design complex wholes and their subsequent integration in hierarchies. buchanan argues that ‘it is attempting to identify and limit specific design professions within each area and shared places of inventions by all designers, places where one discovers the dimensions of design thinking by a reconsideration of problem and solutions’. buchanan wonders why no one has recognized the systematic pattern of invention that lies behind design thinking in the twentieth century. according to him, ‘the pattern is not found in a set of categories but in a rich, diverse and changing set of placement, such as those indentifies by signs, things, actions and thoughts’. from the same perspective, lundequist ( ) argued that ‘the result of a design process is a product where the qualities have been determined (or caused) by the persons involved in the project’. these determinations are decisions based on the occurring reasons (Östman, ). lundequist (referring to rittel and webber) draws the conclusions that ‘it’s a situation with conflicting values, and that the design process is a negotiation process where reasons are put forward and debated, generating a shared opinion of the problem’ (ibid.). ‘for this reason, values are important in design’ (lundequist, ). ‘in a discourse about conflicting values, the answers are not about right or wrong but about good or bad, which, of course, makes it difficult to empirically test the arguments’ (ibid.). ‘design is a process of problem elimination or management. the more the problems can be eliminated the more determined are the qualities of the objects’. according to lundequist, ‘technical, functional and economic reasons are not enough to reduce the possibilities to only one solution. a value-based judgment is necessary. on the other hand, the information given can also restrict the solution of the design process to such an extent that no solution is possible without changing the setting’ (lundequist, ). among design theorists schön, lundequist and buchanan have combined the pragmatist theory ofdewey with design theoretical explorations (buchanan and margolin , Östman, ). wasserman (unpublished , see http://www.designtoimprovelifeeducation.dk/sites/default/files/design_ . _wassermann.pdf) noticed that ‘we have “scaled up” design methodology to address complex problems of corporate strategy, new venture creation, institutional structure and organizational performance as well as public sector programs and policies’. a shift from artifact-centric to socio-centric can be traced ‘as an epistemic shift in what people can agree ones values, beliefs and knowledge that constitute design’. in this socio-centric view, he argues, ‘design is for making better socio-technical systems, experiences, strategies, ventures, organizations, habitats, public policies and programs’. kimbell ( ) looked back on the first practices of design thinking in organizations and collected best practices. first she concludes that ‘the terms design thinking and design attitude are increasingly appearing in the pages of management and organization journals, not just those journals and papers concerned with design’. second, design thinking offers something of value to managers, which can complement analytical techniques. third, citing michlewski’s ( ), five concepts that are part of design culture in organizations. they are: ) consolidating multidimensional meanings; ) creating, bringing to life; ) embracing discontinuity and open-endedness; ) embracing personal and commercial empathy; and ) engaging poly-sensorial aesthetics’ (ibid). she ends her overview with an advice for managers. ‘for management and design practice, the practice-theoretical approach means that designers no longer have to make arguments about why stakeholders or end-users should be at the centre of design. in this approach, they already are. in the practice approach, design is understood to be relational and it cannot be conceived of without people and their practices. further, stakeholders are co-designers and designers are another kind of stakeholder. extending the view of practices as constituting designs through a nexus of minds, bodies, objects, structure, process, agency and knowledge challenges the “human-centred” claims of some part | literature study on organizational aesthetics | organizations and design designers (e.g. brown, ). design practice may appear to be human-centred, since narratives about what people do with things in their day-to-day lives foreground human actors, but attending to designs-in-practice will begin to reveal the practices in which many kinds of actor are involved.’ the most important characteristics of design thinking are expressed in the scheme below (kimbell, ). part | literature study on organizational aesthetics | organizations and design part | literature study on organizational aesthetics | organizations and design table . overview of characteristics design thinking (kimbell, ). before discussing literature on organizational aesthetics, a first overview of similarities and differences of design aspects of the arts, design and organization can be made. aesthetics art design (applied art) organization function aimless expressive and representative meaning joyful and pleasant feeling aesthetic value problem solving, comfort expressive and representative meaning functional value aesthetic value continuity efficient, effective, flexible, innovative functional / economic value actors artist – perceiver designer – marketeer – buyer / user (perceiving in use) employees / managers – customers employees are creators position toward object /artifact towards towards in time / process nature of design process starting from scratch perceiving after production (output) during production (throughput) once starting form scratch - redesign in market and using after production (output) inductive, deductive and abductive once + redesign starting from in dynamic organization continue (input, throughput, output) inductive redesign / development form physic (painting) static / dynamic physic (product) static physic (interior / exterior) people / artifacts static + dynamic mental judgment artist colleagues after and during production critiques after production customers (user-oriented) after production and during use employees / manager customers properties aesthetic non-aesthetic aesthetic (aesthetic properties supervene on non- aesthetic properties) non-aesthetic table . overview of similarities and differences characteristics art, design and organizations part | literature study on organizational aesthetics | organizations and design reflecting on the similarities and differences, characteristics of arts and design could have some implication for adding aesthetic value in organization design. particularly, its function probably would be multiple (being functional and offering aesthetic value) and the employee is the actor who is also perceiving and judging (judgment)these values. and perceiving stimuli in organizations will probably not take place occasionally, but continuously (time). . . organizational aesthetics motivations since guillén ( ) wrote his pioneering article ‘scientific management’s lost aesthetic’ and concluded that ‘we have long neglected the aesthetic context of organizational behavior’, there is a little but growing amount of articles about aesthetics in organizations. ‘aesthetics and the notions of beauty and pathos become part of the vocabulary of organizational discourse in work’, strati ( ) stated. taylor and hansen ( ) argued that ‘organizational research has long focused on the instrumental sphere with its questions of efficiency and effectiveness and in recent decades there has been interest in the moral sphere with its questions on ethics’, referring to the three spheres wilber ( ) distinguished (the instrumental, the moral and the aesthetic). ´aesthetic inquiry is certainly one of the most active movement within the positivist paradigm´, they conclude at the end of their article about ´finding form´. already in , allport et al. ( ) suggested in their mandala model that aesthetic value (‘seeking beauty or harmony’) should be part of organizational design beyond theoretical, economic, political, social and religious value. weick ( ) earlier mentioned ‘the wealth of associative and reactive capacities that people accumulate through lining in a specific physical-cultural setting forms a set of patterns of classifications, interpretation and reaction to perceptual stimuli, ‘sensory maps’ distinguishing them from ‘cognitive maps’. gagliardi ( ) thought about the arguments for neglecting organizational aesthetics. ‘the scientific revolution and the perfecting of the cognitive framework of the natural sciences achieved by newton divided the study of the primary qualities of the physical world – objective, universal and subject to the language of mathematics – from its secondary qualities, which are the object of subjective experiences, sensory and inexact’ he argued. and according to girod, rau and schepige ( ) ´the aesthetic perspective allows us to blend cognitive and discursive ways-of-knowing with all important affective and artistic ways-of-knowing into a more unified, holistic, human understanding.´ the field of ‘aesthetics in organizations’ initially has been explored in the mid ’ s by sandelands and buckner ( ), alvesson and berg ( ),gagliardi ( , ), white ( ), dean ( ), strati ( , ), guillet de monthoux ( , ), and linstead and höpfl ( ), ramirez ( a, b), taylor and hansen ( ), marotto et al. ( , ) and warren ( , ). in the netherlands, de groot ( , ), weggeman and colleagues ( , ) and zandee and broekhuijsen ( ) are concerned about this field of study. organizational aesthetics is a field of study that emerged, largely as a protest against the rational paradigm that dominated organization studies at that time. researchers of this field argued that aesthetic factors, such as emotions, intuition, symbols and sense perception have an equally important role in organization behavior than cognitive activities (koivunen and wennes, ). likewise stimulated by the growing attention of ´human´ issues in organizations like meaning, spiritually and human development in de end of the last century and the budding challenge to combine managing with designing (simon, ; boland and collopy, ; guillet de monthoux, ). part | literature study on organizational aesthetics | organizations and design approaches ‘the underlying assumption of the aesthetic approach to the study of organizations is that although an organization is indeed a social and collective construct, it is not an exclusively cognitive one, but derives from the knowledge-creating faculties of all the human senses’, strati ( ) starts his contribution to one of the two books about organizational aesthetics. according tot strati ( , , ), ‘the aesthetic approach: . shifts the focus of organizational analysis from dynamics for which explanations can be given - or at least for which actor rationales can be reconstructed a posteriori - to dynamics more closely bound up with forms of tacit knowledge (polanyi, ; ). . alters the scholar’s attention rules as s/he conducts empirical and theoretical inquiry. as well as the ratiocinative and abstractive capacities of the subjects who identify with an organization, the aesthetic approach takes account of their ability to see, hear, smell, touch and taste. highlights the heuristic shortcomings of those studies and theories of organization which rely on the causal explanation of organization phenomena. permits exploration of the bond that tie people to organizations for which they work, to their work environment, to the materials that they use and transform: the beauty of the organization that no longer exists and which nostalgia and myth enhance; the beauty of materials and the sense of profound pleasure felt by those who work with them; the beauty of being free form the duty to perform useful work and to make useful things.’ strati ( ) distinguishes the logos (the organizations ‘nature’) , ethos (the organizations moral codes) and pathos (the dimensions of feeling in organizations) in organizational life. he refers to the artifacts ‘that are beautiful to use, graceful to the eye, or grotesque, kitsch or repellent – and to which the language-in-use of organizational discursive practices attaches labels evocative of the aesthetic categories of beautiful, ugly, sublime, gracious and so on.’ artifacts make it possible to rescue the sense beyond the action (monaci, ). this aesthetic approach, strati ( ) continues, ‘which instead becomes necessary when the researcher wishes to examine: . the capacity to make oneself felt, to speak to the heart of people, to arouse their enthusiasm, to touch their feelings, to sensitize them; . the subtle sense of pleasure, as well as of satisfaction, that the taking of a decision may arouse in those concerned; for them, it may be a beautiful decision; . the fact that pleasure and satisfaction are not felt by all the decision-makers. in the eyes of those who have opposed it, the decision may be kitschy and tasteless; . the specific organizational setting in which the decision process unfolds. this setting is distinguished by odours, gestures, voices, the glances and the sensations of the persons who interact in the construction of the decision process and of the decision taken.’ according to gagliardi ( ), ‘aesthetic experiences are mainly observed in artifacts in organizations. artifacts, he said, may be defined as ) a product of human action which exist independently of its creator, ) intentional, it aims, that is, at solving a problem or satisfying a need, ) perceived by the senses’. these artifacts contain so called secondary qualities ‘which are the object of subjective experiences sensory and inexact’, gagliardi observed. without mentioning, he refers to the aesthetic properties which are distinguished in the literature on aesthetics. aesthetic experiences includes (gagliardi, ;): a form of knowledge: sensory knowledge (different form intellectual knowledge), often unconscious or tacit and ineffable, i.e. not to translatable into speech; part | literature study on organizational aesthetics | organizations and design a form of action: expressive, disinterested action shaped by impulse and by a more of feeling rather than by the object (the opposite of impressive action aimed at practical ends); a form of communication (different from speech) which can take place to the extent that expressive actions – of the artifacts which these produce – become the object of sensory knowledge and hence a way of passing on and sharing particular way of feeling of ineffable knowledge. for experiencing aesthetics, according to gagliardi ( ) and similar with literature on aesthetics, the observer needs to have three qualities: ) the capacity of the object perceived, ) the specific ‘pathos’ or pattern of sensibility that the subject has learned by living in a particular physical-cultural setting’ and ) the subjective an contingent willingness to embrace the quality of the object. sandelands and buckner ( ) mention that ‘it is perhaps the idea of aesthetic experience that lies behind the much ballyhooed and perhaps incompletely understood idea of ‘excellence’ in organizations described by peter and waterman ( )’. sandelands and buckner suggest that ´the excellence organization engages its members in transcendent values, values that rise above worldly concerns, values that can play freely at the fringe of awareness and bring aesthetic pleasure.´ they are convinced that there is an aesthetics of work as surely as there is one of art. the reason, aesthetics is neglected in organizations so far, they argue, is because aesthetic experiences are assumed not to be part of practically oriented activities. they contradict this assumption because it is obvious, they assume, ´that aesthetic experiences could ´emerge´ (as a kind of thinking process) as a manifestation of the work itself because of the syntactic (whether thinking in work assumes the aesthetic form) and semantic (what the work means) qualities of the work.´ white ( ) has applied aesthetic criteria to organization design (dean, ). he argue that ‘an organization could be said to have harmony if all its constituent elements coherent with one another (coherent form or pattern) in a manner equivalent to the way all the elements of a work of art cohered with one another.’ dean et al. ( ) argue that the aesthetic perspective tells us the following organizations: people decide to commit in organizational life on aesthetic grounds because of the work and the organization itself; people’s job satisfaction may be influenced by their sensory perceptions of the technologies they work with and the setting in which they work; the resistance to organizational change raised by the people affected by it may be due to the fact that they experience beauty in the work that they already do in organizations or on behalf of them; they defend and protect their aesthetic experience; organizational decision-making should be viewed as a organizational process able to engender aesthetic experience; the design of the organization itself, besides that of its products, may respond to aesthetic criteria such as proportion and harmony. organizational processes in their turn may be influenced by a sense of proportion, of rhythm, of flow, and by the visualization of these properties in flowcharts. they conclude, that ‘beauty can explain a person’s decision to join a organizational process, the success of a certain leadership style, the planning of organization and of organizational processes, resistance against organizational change, reluctance to reach decisions, and worker dissatisfaction with particular technology. these are the aspects of organizational life’, they argue, ‘which demonstrates that aesthetics are important in several respects: the physical and material one of part | literature study on organizational aesthetics | organizations and design technology or the product; the impalpable one of leadership style or satisfaction; aspects closest to the subject like his/her job; ones more distant, like judgment of the organization as a whole; the features most legitimated by organizational ethics like product design; the one least legitimated, like the resistance to change induced by the sentiment of beauty felt with regard with that one is already doing in the organization’. also gerstein ( ) is reflecting on the formal properties of organization design. about organization design, he states that ‘aesthetics deals with design characteristics other than function, performance, and cost that might cause us to prefer one solution over another. surprisingly, perhaps, in organization design intangibles such as aesthetics matter as much as they do in any other arena’ (citing mitchell, ). in organization design, gerstein argues, ‘aesthetic considerations include clarity and simplicity, recognizable repeating patterns, and graceful harmony among design elements’. gerstein implicitly appoints to the earlier mentioned formal properties which are distinguished in aesthetics. ‘environmental conditions are of paramount importance for the aesthetic experience’, csikszentmihalyi ( ) starts his contribution to organizational aesthetics, particularly focusing on the aspect of ‘flow’ in organizations. the conditions for the aesthetic experiences he mentions are the aesthetic environment, the aesthetic object (‘a balance and harmony of form’, perceptual challenge, balance of challenge and skills in the encounter, give meaning for the encounter), the viewer (attentiveness, curiosity, intrinsic motivation, anticipation of reward -> expectation of enjoyment). his arguments are based on his research on the appreciation of art for which context (‘clean, blank, specious environment’, limited information), scale, time (period of maturation), less social activity (derivation) and relation with other ‘different object being frequently noted’ are the most striking (environmental) conditions (csikszentmihalyi, ). cairns ( ) speaks about ‘a concept of aesthetics – the experience and expression of environment through the human senses – as empowering actors within organizations. he proposes a framework both for expression and representation, and for interpretation of their roles, purposes, behaviors and actions at the individual level’. warren ( ) refers to taylor and hansen ( ) who ‘usefully map the terrain of this flourishing scholarly field, classifying texts according to whether their content addresses ‘instrumental’ or ‘aesthetic’ issues and whether their methods of enquiry can be regarded as ‘intellectual’ or ‘artistic’’. taylor and hansen observed that ‘limited attention has been paid to the mentioned fourth classification in this system and suggest this area offers the richest potential for advancing aesthetic understanding in organization studies’. warren noticed that ‘there is a little written about how we might go about this ‘sensory’ research’. ‘’aesthetics’, aesthetic-like feelings and values are a pervading part of the fabric of organizations everyday activities, experiences, judgments and reality’, strati ( ) argues. ‘they imply heuristic- evocative processes of imagination concerning always the interweaving with prior experiences and sensory faculties of aesthetic understanding.’ ‘the aesthetic approach prompts the organization scholar to develop new awareness of organizational life rather than devise new ways to rationalize it. it does so by focusing on matters that the organizational literature until recently regarded as of little relevance to the life of organizations. the study of aesthetics highlights the limits of this convention in theories of organization and shows how they can be overcome’ (strati, ). küpers ( ), building on strati’s insights, wonders if the discussion on this topic so far is fruitful as long as the starting point are only the properties of an organization. ‘organizations are embodying aesthetic “properties” and use various aesthetic symbols and artifacts. certain arrangements of designs and artifices are agreeable, and others the reverse, and they affect our embodiment and bodily states in the context of workplace settings and organizational life’, she said. she suggest that part | literature study on organizational aesthetics | organizations and design ‘the process of organizational activities and dynamics that needs to be examined and understood if we are to find aesthetic insights into the nature of either organizing or the relationship of managing and following. it is the relational aspects, which are critical for an approach of these activities as aesthetic.’ she advocates the use of narrations as an aesthetic process: ‘the responsive, interpreting and judging process can be related to aesthetic communication which may take place in narratives. the re- presentations of telling and sharing stories constitute and open up situations. they create a situation in which an aesthetically oriented subject experiences her-self as belonging to intersubjectively shared life worlds, c.q. as participating in a conduct of life which is constitutive of the organizational life worlds concerned’, she states. referring to fisher, who’s theories are mentioned expanded in the paragraphs earlier about affect in organizations, she claims that ‘stories are a fundamental form in which people express values and reasons, and subsequently make decision about action. the narrative paradigm recognizes the capacity of people to create “. . . new stories that better account for their lives or the mystery of life itself” (fisher, )’. tim brown, ceo of ideo, a consulting firm focused on innovations and organization design, started in spring a discussion on the internet by questioning ‘can organizations be beautiful?’ (see http://designthinking.ideo.com/?p= ). till december people reflected on the question. the most frequent mentioned oas are the consistency of organization aspects (completeness, a whole, unity, pattern, symmetry) (mentioned by % of the respondents), responsive and engagement with environment (mentioned by % of the respondents), collegiality / cooperation / harmony (way of working together) (mentioned by % of the respondents), autonomy / independence (mentioned by % of the respondents), flat structure, no hierarchy (mentioned by % of the respondents), flexibility / dynamics (mentioned by % of the respondents) and development opportunities / personal development (mentioned by % of the respondents) (see appendix ). of ( %) oas were mentioned by two or more respondents and of ( %) oas were mentioned by three or more respondents. categorizing the oas cited by the respondents according to the parameters of the esh-model, we can see that the items are fairly evenly divided among the parameters: five items are related to structure, four items are related to staff, nine items are related to system, four items are related to management, five items are related tot strategy and four items are related to culture in the netherlands, weggeman ( ), akkermans et al. ( ) and van aken ( ) start their reflections with the distinction between the true, the good and the beautiful (based on plato and revitalized by habermas, ). they argue that ‘organization studies have out a strong emphasis in the first perspective and that also the ethics perspective is gaining ground if we look into notions like qualitative management, sustainability and corporate citizenship.’ they wonder whether aesthetically organizational processes lead to more successful organizations and better performance. they propose a conceptual model for the impact of aesthetics on organizations, which can be considered as a process model (input-throughput-output). aesthetic sensibility of employees and managers combined with a aesthetic quality of organizational design (system aesthetics) will lead to or combined with process aesthetics will lead to result aesthetics: well being of organizations members and an aesthetic quality of products and services (akkermans et al., ). later, in , they propose to regard organizational beauty as a cluster concept. this means that a beautiful organization is not defined by a number of necessary properties, together being sufficient, but a cluster of properties associated with the concept of a beautiful organizations (van aken et al., ). part | literature study on organizational aesthetics | organizations and design recent, rindova et al. ( ) and earlier peng, wen-shien ( ) drawing on the core ideas of classical gestalt theorists, like koffka ( ) and wertheimer ( ). ‘an important characteristic of gestalt properties is that they are not present in the component parts of the stimulus; therefore, their effects cannot be derived from observing the component parts in isolation’ (rindova et al., ). according to rindova et al., ‘precisely because they integrate the parts in a perceived whole, gestalt properties increase the processing fluency and the ease of interpretation of a stimulus.’ gestalt properties stimulate positive evaluations’, they argue. ´the idea that gestalt properties affect the perception and evaluation of unfolding sequences of events has found applications in a variety of areas, including judgments of personal experiences, performance appraisals, and valuing and spending money. in the administrative sciences, some of these processes have been associated with sensemaking, pattern recognition, and alertness to competitive patterns and entrepreneurial opportunities.´ rindova et al. ( ) proposed four gestalt properties (simplicity, predictability (repetition), grouping, and motif) as having the potential to positively affect investor evaluations of firms. they conclude that ´the gestalt properties present in competitive action sequences can provide firms with competitive advantages in access to resources.´ they theorized and tested the effects of the four mentioned gestalt properties on investor valuations and provided ´general support for the overarching theoretical argument, as well as specific support for the hypothesized positive effects of simplicity, grouping, and motif on investor valuations of firms operating in the high-ambiguity condition.´ finally, de botton and sennett shine an almost poetic light on work and organizations that has some parallels with aesthetics. de botton ( ) highlighted in his book 'the pleasures and sorrows of work' not directly an aesthetic perspective on labor, but during his reflections on a biscuit industry, distribution centers and aircraft industry, he frequently uses the term ´beauty´. he speaks of the beauty of passion, dedication and diligence in the work, the complexity (and collected in such simplicity in a formula), skills and completing and realizing something (it was successful! '). he also considered new insights and breakthroughs, "create things that you go beyond" and modern technology beautiful as well as the feeling of competence, if that one indentifies with an activity (identification), leads to the feeling of pride, ‘good acting' and meaningful work. sennet ( ) cites on his own homepage about his book ‘the craftsman’: ‘the craftsman names a basic human impulse: the desire to do a job well for its own sake. although the word may suggest a way of life that waned with the advent of industrial society, sennett argues that ´the craftsman’s realm is far broader than skilled manual labor; the computer programmer, the doctor, the parent, and the citizen need to learn the values of good craftsmanship today’. the craftsman: ) recognizes the importance of the sketch (you do not know exactly what to do when you begin, ambiguity), ) committed to unforeseen events and constraints, ) avoid a problem so severe that he tackled is that it is completely self to stand, ) perfectionism goes out of the way (but 'toils' in the temporary removal of the desire for completion), ) and learn when it's time to stop. sennet points out the importance of (planned) for professionals. he cites the example of a designer who is out there for others to learn from temporary disorientation, to deal with ambiguity. he also uses the term in the transition, a ‘porous membrane’, of effectiveness and stinginess, which possibly may be of interest for the relationship between functionality and beauty. by the users to learn to deal with ambiguity, ‘they learn to navigate the edges of two fields’, says sennett. about change, sennett speaks of four stages of change in the work of professionals: reformatting, 'juxtaposition placement’(functionality as well as beauty: ’ the more they approach each other how stimulating their entanglement seems'), the intuitive leap (the surprise) and the recognition of the jump ('gravity'). part | literature study on organizational aesthetics | organizations and design in sum, except that terms like ´experience economy´, ´aesthetic knowledge´ and ‘aesthetic organization’ were born, these first studies on aesthetics in organizations have also described the first concepts, without testing these ideas in practice. these are: process beauty (akkermans et al., ; van aken et al., ); organizational design beauty (akkermans et al., ; van aken et al., ); formal properties (harmony, balance, rhythm, simplicity, repetition) in organization design (dean, ; white, ; gerstein, ; rindova et al., ) and organization as a whole (gestalt) (rindova et al., ; peng, wen-shien, ); the artifacts that constitute the organization’s corporate landscape (strati, ; alvesson and berg, ; taylor and hansen, ; sandelands and buckner, ); the physical space of the organization(strati, ; alvesson and berg, ; witz et al, ; taylor and hansen, ); the idea that work compromises an essential aesthetic element (strati, ; alvesson and berg, ; taylor and hansen, ); organizational decision-making (dean et al., ); aesthetic leadership: organizational management that can learn from art (artistic form) (strati, ; alvesson and berg, ; taylor and hansen, ); product or services beauty (witz et al., ; akkermans et al., ; van aken et al., ); the images that diffuse internally and externally to the organization (strati, ; alvesson and berg, ; taylor and hansen, ); dedication to work and diligence in the work (de botton, ); complexity (and collected in such simplicity in a formula) (de botton, ); completing and realizing something (‘it was successful!’) (de botton, ); craftsmanship (sennet, ). research agenda the main contribution of the organizational aesthetic research so far, is raising the issue as a possible and neglected new perspective on organizations and suggesting research questions for this field of research. according to gagliardi ( ), the first challenge of research on this filed is that there is a clear need for the material world to be brought within the ‘aesthetic frame of reference’. the few worldwide researchers on this topic developed a research agenda - may be the only real contribution on this topic - with the following domains and elements, (strati, ; alvesson and berg, ; taylor and hansen, ): . the images that diffuse internally and externally to the organization and relate to events of importance for organizational identity and for identification by its members; . the physical space of the organization; . the miscellaneous set of artifacts that constitute the organization’s corporate landscape; . aspects less closely tied to the physical-spatial or visual, like the metaphor of manager as artist, the idea that work compromises an essential aesthetic element, the phenomenological philosophy of the eye, and strategic visions of the organization; . organizational management that can learn from art more as artistic form than as artistic content. taylor and hansen ( ) distinguishes a matrix in with content (instrumental and aesthetic) and methods (intellectual and artistic) causes four categories of organizational aesthetic research. these categories, they say, ´help researchers to be more conscious of the ways they approach organizational aesthetics and the implications of differing methods and content´. warren ( ) comprises three interconnected parts of possible research issues in this field: part | literature study on organizational aesthetics | organizations and design . the assumption that an aesthetic experience is distinguished because of external object or event (broadly defined) as a ‘trigger’. here, following linstead and höpfl ( ), she conceptualized aesthetics as an oscillation between the two - aesthetic experiences/judgments are subjective reactions to material things (real or imagined) but cannot be reduced to one or the other. . aesthetic experiences are universal, embodied, sensory, modes of human being-in-the-world. she is following the original meaning of baumgarten’s doctrine of philosophical aesthetics to denote a kind of ‘sensible knowledge’ (strati , ) that is open to all rather than reserved for the production, consumption and criticism of ‘high art’. . however, ‘the aesthetic’ is characterized by two quite conceptually distinct elements— experience and judgment—the latter being an intersubjectively constructed appraisal of the former, influenced by socialization processes and ‘habitus’ (bourdieu ). as welsch ( ) puts it, aesthetics has a ‘double character’. in the netherlands, akkermans et al. ( ) and later van aken et al. ( ) drew up a research agenda for aesthetics in organizations as well: what are relationships between: . product or services beauty and business performance . process beauty and beauty of products and services; . personal well-being and process beauty; . personal well-being and the beauty of products and services; . organizational design beauty and organizational process beauty; . aesthetic sensibility and organizational design beauty; . education and aesthetic sensibility and later: . what is a beautiful organization (what features or characteristics) . what conditions are needed to create organizational beauty? . what is the relationship between beauty of organizations and work processes and performance? . what approaches can be used to design, create or enhance and sustain organizational beauty? strati ( ) proposed ‘a new approach to studying organizations which is based on the evocation of knowledge, on mythical thinking, and on the criterion of plausibility’. gagliardi ( ) advocated the use of ‘allusive poetic language’ for collecting and interpreting aesthetic data. strati ( ) and also marotto et al. ( ) experimented with (imaginary) participant observation. strati advices researchers ‘to begin by arousing and refining their own sensory and perspective faculties’. and thus, ‘relying heavily on the intuitive and aesthetically responsive skill of the researcher in this regard, and moreover, on the expressive capabilities of both respondents and researchers alike’ (warren, ). rusted ( ) called this a researcher-as-commentator or ‘connoisseur’ perspective. warren ( , ) used a what she called an ethno-methodological approach by following people daily for three months in their company, interviewing them (‘rich narrative data’) and took pictures and discussed them (´talking pictures´ as part of the technique of photo-elicitation) with her respondents. research by using similar ethnographic methods has been done by tyler and taylor ( ), hancock and tyler ( ) and strati ( ) and witz et al. ( ). taylor and hansen ( ) are supporting a ‘constructionist view of aesthetics as sensory knowledge rooted in experience’ and propose ethnographic and narrative methods for acquiring data of aesthetic experiences. van aken et al. ( ) provide methods useful like ethnographic case studies draw on the approach and methods of appreciative inquiry and a action research approach. part | literature study on organizational aesthetics | organizations and design the few contributions on aesthetics in organizations mainly raise the question whether aesthetics in work and organizations could be an additional or new perspective on organizations. some of the contributors like akkermans et al. ( ) van aken et al. ( ) and gagliardi ( ) make suggestions which oas (like organization design parameters) cause aesthetic experiences. after conducting the empirical studies, these suggestions can be confirmed. but these contributions do hardly distinguish the several categories of aesthetic properties the literature on aesthetics describes, neither the detailed process of the aesthetic experience and its outcome: the judgment and the related emotions. thereafter, the relationship with design principles of organization design or any other design discipline is little discovered so far, neither the revenues of this additional or new perspective on organizations like affective commitment, pride of work pleasure. nevertheless, the research agenda they all together constructed offered fruitful suggestions for this dissertation. . conclusions this chapter about organizations and design aspired to answer three research questions related to this field of interest by collecting insights of organization design and other design disciplines, the common used design principles in these design disciplines and the state-of-art knowledge of aesthetics in organizations. considering the defined research questions, the following insights are useful: the few contributions on organizational aesthetics mainly raise the question whether aesthetics in work and organizations could be an additional or new perspective on organizations. the attention for aesthetic aspects (aesthetic properties, aesthetic experiences and value) as well as the distinction of types of aesthetic properties which are used in aesthetics are largely missing in the current organization design approach; the esh-model (based on mckinsey’s -s model) or weisbord’s six-box model seems to be most the fruitful models for designing organizations in which aesthetic aspects can be uncovered and embedded; organizations are changing to more responsive, sensible and life affirming organizations in which creating value, sense making and meaning, narrative experiences and relations between employees become important. an aesthetic perspective on organizations fit within these developments; principles of design thinking like abduction, through collaboration and human-centered could enrich the current perspective on organization design. part | literature study on organizational aesthetics | emotions in organizations emotions in organizations this research proposes a framework wherein the relationship between organization design features, aesthetic experiences and emotions in organizations, particularly affective commitment of employees is described. it aspires that by increasing positive aesthetic experiences and decreasing negative aesthetic experiences through features of work conditions (organization design), the affective commitment of the employees will increase as well. before examining and influencing affective commitment, this relatively new term in organizations needs to be described and related to aspects like emotions, work feeling and emotions in organizations. therefore, most important research questions for this part of the literature study were: what is the relationship between aesthetic experiences and emotions in organizations? how can aesthetic experiences be related to organization’ outcomes such as employee commitment, satisfaction and performance? this last part of literature research will discuss the following topics: a. affect at work; b. affective commitment; c. conclusions. because the sections are short, there are hardly any interim conclusions appointed. . affect at work issues like affect, work-feeling, moods, happiness and emotions have recently entered organizations, at least the examination of it (seo, barrett and bartunek, ; fineman, ; mignonac and herrbach, ). major work on this topic has been done by fineman, ahskanazy and fisher the last two decades. according to seo, barrett and bartunek ( ), four distinctive streams of research can be distinguished: ) the expression, exploitation and management of emotions, ) the effect of emotional intelligence in individual and organizational performance, ) the effects of trait affectivity or affective disposition on individual performance and ) antecedents and consequences of momentary affective experience (moods and emotions) in organizations. in her extensive examination on happiness at work, fisher ( ) reflects on the antecedents and consequences of this topic. first she notices that many organizational researchers since the beginning of this century have been inspired by the move toward positive psychology in general. for example, positive organizational scholarship has been examined by cameron, dutton, and quinn ( ), positive organizational behavior has been grasped by luthans ( ) and wright ( ) and researchers like fineman ( ), hackman ( ), luthans and avolio ( ), roberts ( ) and earlier sandelands and buckner ( ) immersed themselves into the topics of encompass and work- feeling. ashton-james and ashkanasy ( ) refer to the groundbreaking article of pekrun and frese ( ) about emotion and affect in organizational setting and listed more than twenty articles and edited books which contribute to these topics since then. ‘state affect or mood is comprised of feeling states that are relatively enduring and without a salient antecedent cause’ (watson, ). ‘state affect is distinguished from emotions which are more intense, shorter lived and have definite cause’, little ( ) argues. russell ( ) distinguishes state affect form trait affect (dispositional affect, the tendency of a person to experience an affective state over time) and emotion by arguing that ‘state affect does not have a cognitive component, as part | literature study on organizational aesthetics | emotions in organizations experienced in relation to no known stimulus and as continuous or always present’ (little, ). ‘state affect, is akin to mood and is commonly characterized as being positive or negative. state affect is generally studied as two constructs, positive and negative. however, studies have also shown that individuals can also experience affective ambivalence’, she mentions, referring to amabile et al. ( ). ‘emotion is composed of other components including appraisal, physiological and expressive changes and attribution’ (little, ). ‘emotion and state affect (mood) are thought to be malleable while trait affect is more a stable component on one’s personality’ (e.g. watson and clark, , cited by little, ). rosenberg ( ) proposes a hierarchy ordering of the levels of affect. duration, pervasiveness in consciousness and distributive breath (‘the range of different psychological and physiological processes that can be influenced by any other given process’) are the three criteria according to her, ‘which made that affective traits, moods and emotions can be distinguished from each other’. ‘affective traits are highest in the hierarchy because they organize lower level emotional states’, she said. herrbach ( ) examined the relationship between trait and emotions and conclude that ‘individuals whose level of positive trait affect is high tend to experience more positive moods or emotions across various situations than individuals whose level of positive trait is low. likewise, individuals with a high level of negative trait affect tend to experience more negative affective states compared to low negative-trait affect individuals.’ thus, moods can be defined as feelings that tend to be less intense than emotions by a lack of a contextual stimulus. emotions are intense feelings that are directed at someone or something and affect is a broad range of emotions that people experience. ahskansy ( ) described a multi-level perspective on emotions in organizations. the first thing he concludes is that ´terms such as emotion, mood, affect, and feelings appear to be used almost interchangeably by some authors. indeed, there is ongoing debate in the literature about the very underpinnings of emotions and related terms (see for example, eisenberg, ; izard, ; lazarus, ; plutchik, ; zajonc, , , )´. while lazarus ( ) argued that ‘emotions are initiated by cognitions, contemporaneously’, zajonc ( ) argued that ‘emotions are essentially visceral reactions and therefore constitute antecedents, rather than consequences of cognition’. since the s, ahskanasy concludes that ‘the consensus has emerged that emotions involve an interaction of cognitive and non-cognitive neural systems’ (see bloom, lazerson and hofstadter, ; cacioppo and gardner, ; dalton, ; fischer, shaver and carnochan, ). in this respect, he states, ´emotion is seen as an integration of innate, adaptive subsystems, derived from the evolutionary needs of survival (ledoux, a; tooby and cosmides, )´. mood at work mood, instead of emotion, can be considered as ‘an experimental phenomenon which is not directed towards an object’ (morris, ; weiss and cropanzano, ). moods can be defined as feelings that tend to be less intense than emotions and that lack a contextual stimulus. while moods are be considered as an antecedent of aesthetic experiences (e.g. basch and fisher, ; mignonac and herrbach, ; fisher, ; wagner and libkuman, ) it needs to be described in brief.’ although not as rapidly varying as emotion, mood nonetheless constitutes a distinct additional source of within- person variability’ (ahskanazy, , referring to gray and watson, ; oatley and jenkins, ) and an important determinant of decision making and behavior in social (forgas, ; isen, ) and organizational settings(see george and brief, , a). in respect to positive mood, isen and her has colleagues (ahskanazy, cited isen and daubman, ; isen, daubman and nowicki, ; isen, johnson, mertz and robinson, ) have provided evidence that positive affect results in creativity and cognitive flexibility. positive mood is associated with positive outcomes, including better job satisfaction (connolly and viswesvaran, ), less turnover (shaw, ), more helping behaviors at work (williams and shiaw, ), better negotiation part | literature study on organizational aesthetics | emotions in organizations outcomes (carnevale and isen, ), and improved performance (cropanzano and wright, ; wright and staw, ). kraiger, billings and isen ( ) have also shown that ‘positive affect leads to more positive evaluations of jobs, although only when the jobs were already seen to be rich and meaningful’, according to ahskanazy. negative mood on the contrary less straightforward than positive mood, clark and isen ( ), kaufman and vosburg ( ), and rusting and dehart ( ), ahskanazy concludes. ´people in a negative mood are often motivated to perform more positively so that they can change their mood to a positive one. thus, people in a negative mood often appear to behave incongruously – displaying more helping behavior and working more productively´. nonetheless, as george and brief ( ) point out, ´people in negative moods are still generally less satisfied with their jobs and are more likely to want to leave their jobs´. ahskanazy ( ) summarizes the present discussion of within-person emotion and mood. he states ´clear that these are important, but neglected dimensions in organizational behavior research. recent research into emotions at work, based on affective events theory (aet), advocate the potential for improving our understanding of how and why people behave and think in organizational settings.´ views on affect at work fisher ( ) concludes that ‘these kinds of emotions can be divided into hedonic views of emotion as pleasant feelings and favourablejudgments versus eudaimonic views of emotion involving doing what is virtuous, morally right, true to one’s self, meaningful, and/or growth producing’ (cropanzano et al., ; ryan and deci, ; ryff and singer, ). ‘the hedonic view is exemplified by research on subjective well-being, which is usually seen as having two correlated components: judgments of life satisfaction and affect balance, or having a preponderance of positive feelings and relatively few or rare negative feelings’ (diener, suh, lucas, and smith, ; schimmack, ). research on the structure of affect, mood, and emotions consistently, according to fisher, ‘finds that the most important dimension in describing individuals’ affective experiences is hedonic tone, or pleasantness – unpleasantness’ (watson, wiese, vaidyaand tellegen, ). in contrast to this view of emotions as involving pleasant feelings and judgments of satisfaction, fisher argues, ´eudaimonic well-being, self-validation, self-actualization, and related concepts suggest that a happy or ´good´ life involves doing what is right and virtuous, growing, pursing important or self- concordant goals, and using and developing one’s skills and talents, regardless of how one may actually feel at any point in time´. first research of people like warr ( ), seligman ( ) and sheldon and elliot ( ) on this topic needs to be mentioned. what these views have in common, fisher notices, is ‘that both refer to pleasant judgments (positive attitudes) or pleasant experiences (positive feelings, moods, emotions, flow states) at work’. derbaix and pham ( ) investigated affective reactions especially to consumption situations. they conclude that ‘research on affective reactions at work can be characterized along four dimensions: antecedents, intensity, duration and specificity’. emotions in organizations thinking about aesthetic experiences in organizations means thinking about emotions. ‘the first level of response to the environment is affective’, ittelson ( ) claimed. freedman ( ) proposed that ‘the psychological effects of a crowded environment are mediated by the pleasantness of the other factors in that environment’. and other psychologists like glass, singer, stoklos and milgram employed in the seventies the concept of stress, work overload or other concepts with clear affective components. in this period the first types of emotions in organizations like arousal, environmental quality, comfort, annoyance and aesthetically pleasing quality arose. affect were defined as ‘emotion expressed in language, and affective quality of a molar physical environment (or more simply expressed, a place), as the emotion-inducing quality that persons verbally attribute to that place’ part | literature study on organizational aesthetics | emotions in organizations (russell and pratt, ). ‘the structure of affective experience has been described within different models and structures’, giardini and frese ( ) argues. they conclude that ‘affective experience can be structured in two or three dimensions seem to emerge’ (russell ): pleasantness (or evaluation, valence), arousal (or activity, activation), and power (or potency, dominance). of these three structures, pleasantness is the most frequently found dimension of affective experience, combined with either arousal (russell, lewicka and niit, ) or power (gehm and scherer, ). in literature, two lists of emotions are dominant. first, the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix (the ‘unrotated solution’: affect tone and affect intensity), and second, the panas-circumflex (the ‘rotated solution’: positive affectivity and negative affectivity) of watson, clark and tellegen ( ). russell, ward and pratt ( ) proposed a two dimensions-pleasure-displeasure and degree of arousal-denote matrix (later also indicated by others in two dimensions of ‘excitement-calm’, ‘affect intensity’, ‘activation’ and ‘engagement’) in which they positioned first twenty-one clusters of adjective descriptive of the affective quality of places: forceful, hectic, frightening, harsh, frustrating, ugly, disgusting, unstimulating, depressing, boring, insignificant, desolate, sleepy, peaceful, conformable, beautiful, enjoyable, festive, majestic, active and exciting. later they brought these descriptors back to eight affective descriptors and ranked them in bipolar scales: arousing-sleepy, exiting-gloomy, pleasant-unpleasant and relaxing-distressing (see table . ). they dubbed these descriptors as qualities and developed shades per quality in order to obtain detailed affective responses for measurement. positively keyed items negatively keyed items arousing quality intense arousing active alive forceful sleepy quality inactive drowsy idle lazy slow exiting quality exhilarating sensational stimulating exciting interesting gloomy quality dreary dull unstimulating monotonous boring pleasant quality pleasant nice pleasing pretty beautiful unpleasant quality dissatisfying displeasing repulsive unpleasant uncomfortable distressing quality frenzied tense hectic panicky rushed relaxing quality tranquil serene peaceful restful calm table . overview of types of emotions (russell, ward and pratt( ) part | literature study on organizational aesthetics | emotions in organizations in they developed the two dimensions-pleasure-displeasure and degree of arousal-denote matrix in the watson, clark and tellegen circumflex (see figure . ), affect is based on dimensions of positive (high versus low) and negative (high versus low) affect whereby eight emotions are described: exulted / enthusiastic / excited, aroused, fearful / nervous / hostile, drowsy / sluggish, quiet, calm and happy. figure . the watson, clark and tellegen circumflex russell and carroll ( ) argue that the basic dimension is the rotated axes or dimensions of activation (engagement) and pleasantness (see figure . ). figure . rotated dimensions of activation and pleasantness (russell and carroll, ) part | literature study on organizational aesthetics | emotions in organizations according to seo, barrett and bartunek ( ), activation refers to ‘a sense of mobilization or energy and summarizes one’s psychological state in terms of its level of activation or deactivation’. russell ( ) does not believe that a person can experience both state positive affect and state negative affect at the same time. but empirical evidence (folkman, ; beach and tesser, ; goldstein and strubed, ) pointed out that individuals are able to feel multiple states of mind. in addition (little, ), states that ‘physiological theories point to the co-occurrence of state positive and state negative affect. neuroscientists and theorists have posited that affect is produced by two specialized channels – one in which threat-related (negative) information is derived and the second from which safety and appetitive (positive) information is derived (e.g. cacioppo and gardner, ; gilbert, ; marcus and mackuen, ; watson and clark, ).’ basch and fisher ( ) emotions (joy, pride, fear, anger, and disgust) differ from watson and tellegen’s ( ) emotions in their ´circumplex model of affect’, and differ from russell and feldman- barrett proposal in which the core affect is based on dimensions of pleasantness and activation. similar to carver ( ), ahskanasy ( ) argue that ‘adoption of the appropriate model of emotion is contingent on the question being addressed.’ gray and watson ( ) and finn and chattopadhyay ( ) conclude likewise that ‘discrete emotions, affect, and mood are reciprocally interrelated, and that choice of which model is most appropriate depends on the purpose of the analysis and the functional nature of outcomes’. cropanzano et al. ( ) extensively compared data of both ‘solutions’ (the unrotated solution: affect tone and affect intensity versus the rotated solution: positive affectivity and negative affectivity). they conclude that ‘both models work in a general sense that a) it is possible to obtain the predicted factor structure, b) there is theoretical evidence consistent with each, and c) each frame work yields testable propositions.’ they integrated both models and proved that ‘pa roughly corresponds to high hedonic tone / high arousal, while na roughly corresponds to low hedonic tone / high arousal.’ ‘there are no markers for low activations’, they conclude. schimmack and reisenzein ( ) suggest that ‘it would be more meaningful to assess separately the basic dimensions of pleasure-displeasure and activation-deactivation.’ they proved that ‘there is no evidence for the assumption of pleasure-activation theory that pa and na share common activation dimension’, also watson ( ) proved. their finding supports the two-dimensional models of activation that regard energetic arousal and positive activation and tense arousal and negative activation as two largely independent activation dimensions. because of the substantial theoretical and empirical support for the co-occurrence of state positive and state negative affect, the panas-circumflex of watson, clark and tellegen ( ) seems to be more reliable than the russell, ward and pratt ( ) matrix, although this one is very often used in research so far as well (schimmack and reisenzein, ). part | literature study on organizational aesthetics | emotions in organizations ashkanasy ( ) developed the simplified emotional hierarchy (based on fischer et al, ) which contains two super-ordinate components, five basic components and fifteen subordinate components. super-ordinate components basic components subordinate components positive love fondness infatuation joy bliss contentment pride negative anger annoyance hostility contempt jealousy sadness agony grief guilt loneliness fear horror worry table . overview simplified emotional hierarchy (ashkanasy, ) basch and fisher ( ) conclude that ‘with only a few exceptions, employees experience nearly the full range of emotions in their workplace, together with emotions more specific to the work environment’ (ashkanasy, ). in descending order of frequency of occurrence, basch and fisher found that employees report feeling positive emotions of pleasure, happiness, pride, enthusiasm, relief, optimism, affection, and power. the negative emotions reported by basch and fisher, again in descending order of frequency, were frustration, worry, disappointment, annoyance, anger, unhappiness, embarrassment, sadness, disgust, hurt, fear, and bitterness. lazarus and cohen-charash ( ) list anger, anxiety, guilt and shame, envy and jealousy, hope, happiness/joy, pride, compassion, and love as instances of discrete emotions that are found in workplace settings (ashkanasy, ). mutual influence of positive and negative emotions research of diener , sandvik and pavot ( ) suggest that ‘it is more satisfying to be at least a little happy most of the time than to be intensely happy from time to time’ (fisher, , ). cohn ( ) suggested that ‘people judge their lives to be more satisfying and fulfilling not because they feel more positive emotions per se, but because their greater positive emotions helped them build resources for living happily and successfully.’ several research has been done on the relationship between positive and negative emotions. fredrickson ( ) and later cohn et al. ( ) and amabile and kramer ( ) suggest that ‘high levels of positive emotions reduce the impact of any increase in negative emotions, but high negative emotions do not reduce the impact of positive emotions’. this latter conclusion is contradicts a finding of baumeister. baumeister et al. ( ) like others distinguish a positive–negative effect asymmetry. ‘bad events had longer lasting effects. and bad events seem to produce stronger reactions than good ones’ they argue. they claim ‘there is an assortment of evidence that negative affect is stronger and more important than positive affect’. they also suggest that ‘people try harder to avoid and escape bad moods than to part | literature study on organizational aesthetics | emotions in organizations induce or prolong good moods, and they remember bad moods and emotions better.’ and conclude that ‘bad events influenced both good and bad moods, whereas good events influenced only good moods.’ brickman et al. ( ) indicate that ‘after a short peak in happiness, people become accustomed to the new situation and are no more happy than they were before the improvement’ ("nostalgia effect"). recently amabile and kramer ( ) conclude that ‘three types of events stands out as particularly potent forces supporting inner work life, in this order: progress in meaningful work; catalyst (events that directly help project work); and nourishers (interpersonal events that uplift the people doing work)’. the negative forms setbacks in work, inhibators (events that directly hinder project work) and toxins (interpersonal events that undermine the people doing the work). levels of influence fisher ( ) distinguishes three emotion-related constructs (levels) in the work place: . transient level: real time affective work events and the short-lived moods and emotions that individuals might experience as a result like state job satisfaction, flow state or task enjoyment; . person level: the emotions of individuals expressed in dispositional affectivity, affective commitment and typical mood at work; . unit level: the emotions of collectives like teams, work units, or organizations. ashkanasy ( ) proposed a five levels of emotions in organizations quite similar to fisher’s emotion- related constructs, but more divided and provided of affective abstracts: . within-person: state affect, affective events, discrete emotions, mood and behaviors; . between persons: trait affectivity, affective commitment, job satisfaction, burnout and emotional intelligence; . interpersonal interactions: emotional labor, emotional exchange, displayed versus felt emotion; . groups: affective composition, emotionally intelligent groups, emotional contagion, leader- member exchange; . organizational-wide; organization policies, requirements for emotional labor, stress and wellbeing, emotional climate and culture; special aspect related to the affective abstract of between persons, several studies (e.g. giardini and frese, ) showed that contagion processes (expressions of friendliness and sympathy elicit corresponding reactions) can also be found on the level of employees’ and customers’ experience of positive affect. fisher ( ) describes the most distinguished constructs of emotions which are job satisfaction, organizational commitment, job involvement, engagement and flow and intrinsic motivations. fisher concludes that in particular job satisfaction and organizational commitment are the most frequently studies constructs. she suggests distinguishing three targets for emotions (‘happy feelings’ in her description): ) the work itself, ) the job including contextual features, and ) the organization as a whole. further, she proposes three measures together which should capture much of the variance in person level happiness in organizations. these are ) engagement, representing affective and cognitive involvement and enjoyment of the work itself; ) job satisfaction, representing largely cognitive judgments about the job including; and ) affective organizational commitment, as feelings of attachment, belonging, and value match to the larger organization. going deeper into the aspects of affect of work, she concludes that ‘in contrast to some of the above part | literature study on organizational aesthetics | emotions in organizations constructs that involve attitudes and/or cognitions, measures of affect at work directly assess moods or emotions experienced while working.’ in the discussion between the two mentioned views (‘the traditional affect circumplex features two dimensions’, fisher, ) weiss and cropanzano ( ) suggest that ‘the former conceptualization (hedonic tone and arousal) is most useful for measuring state mood at work’. some scholars believe that hedonic tone is by far the more important and useful of these two dimensions, particularly in the workplace (daniels, ; russell, ; warr, ). others, like weiss, nicholas, and daus ( ) found that ‘average hedonic tone while working was correlated with job satisfaction while average activation level was not’, fisher mentions. finally, fisher ( ) describes the causes of emotions in organizations. in her contribution, she focuses on the causes of happiness, but many of her findings can be abstracted to general emotions. fisher, like others, states that three reasons can be mentioned why people have changed emotions: . something in the environment or circumstances of the person; . something inside the person predisposes him; . an interaction of person and situation; . volitional behaviors impact emotions. deci and ryan ( ) developed the cognitive evaluation theory (cet). they argue that ´events and structures (e.g. rewards, communications, feedback) that conduce towards feelings of competence during action can enhance intrinsic motivation for that action because they allow satisfaction of the basic psychological need for competence.’ kesebir and diener ( ) found out that objective life circumstances account for - % of the variance in the subjective well-being. fowler and christakis ( ) have recently shown that ‘individuals are likely to become happier if a close friend or neighbor has become happier in the preceding six months’, fisher mentions. according to her, ‘at the transient level of positive moods and pleasant emotions, immediate situational occurrences clearly are important in explaining variance in happiness within person over time. individuals experience positive emotions when they appraise a current situation or event as beneficial to their interests, or as representing progress toward important goals’ (citing frijda, ; lazarus, ). amabile and kramer ( ) argue that ‘during goal progress, people meet their personal goals and the match between expectations. their reading or reality allows then to feel good and their self positive self-efficacy grow’. another example fisher mentions is a pair of studies based on self-determination theory showed that ‘individuals have happier than usual days compared to their own baselines when they experience greater satisfaction of basic needs for competency, autonomy, and relatedness in major activities during the day’ (reis, sheldon, gable, roscoe, and ryan, ; sheldon, ryan, and reis, ). measuring emotions there are a number of measures of affect at work, fisher ( ) concludes. like concluded earlier, in literature, two lists of emotions are dominant. first, the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix (the ‘unrotated solution’: affect tone and affect intensity), and second, the panas-circumflex (the ‘rotated solution’: positive affectivity and negative affectivity) of watson, clark and tellegen ( ). russell, ward and pratt ( ) proposed a two dimensions-pleasure-displeasure and degree of arousal-denote matrix (later also indicated by others in two dimensions of ‘excitement-calm’, ‘affect intensity’, ‘activation’ and ‘engagement’). by the prominence of the two approaches are also the two related methods (questionnaires) commonly used. part | literature study on organizational aesthetics | emotions in organizations questionnaires beside these two questionnaires, fisher ( ) herself constructed the job emotions scales by selecting positive and negative emotion terms (affection, pleasure, happiness, pride, optimism, enthusiasm, frustration, anger, disgust, unhappiness, disappointment, embarrassment and worry) from the prototypical emotions identified by shaver, schwartz, kirson, and o’connor ( ). items were chosen based on how frequently they were experienced at work and breadth of coverage of shaver et al.’s hierarchical cluster analysis of emotion categories. ‘the job emotion scales focus on the hedonic view without regard for arousal, and contain terms associated with specific emotions rather than more generalized moods’, she says. another measure of positive and negative affects is worldwide performed with watson and tellegen’s ( ) positive and negative affect scales (panas). the affect schedule is a -item self-report measure, ‘that has widely most been used to measure affect at work with frames of reference ranging from current moment to past week to past month to work in general’ (schimmack and reisenzein, ; cropanzona et al., ). in other cases, the panas has heavily influenced the development of work-related affect scales. because of the substantial theoretical and empirical support for the co-occurrence of state positive and state negative affect, the panas-circumflex of watson, clark and tellegen ( ) seems to be more reliable than the russell, ward and pratt ( ) matrix, although this one is very often used in research so far as well (schimmack and reisenzein, ). the modified differential emotions scale (mdes), developed by fredrickson, waugh, tugade and larkin ( ), asks participants to rate the extent to which they are experiencing discrete emotions, including both high- and low-arousal pleasant and unpleasant emotions (e.g., amusement, contentment, anxiety, and sadness), on a zero to eight scale (cohn, ; waugh and fredrickson, ). the affect grid later, russell, weiss and mendelsohn ( ) developed the affect grid. it was designed to record judgments about single instances of affect (one-item measure), particularly to assess two dimensions of affect: pleasure-displeasure and arousal-sleepiness. ‘compared with the very often used panas (and later the panas-x) method, the grid produced similar estimates of predictive power’, they proved. other often used methods of measures of affect at work are the job-related affective well-being scale (van katwyk, fox, spector, and kelloway, ), the job affect scale (brief, burke, george, robinson, and webster, ; burke, brief, george, roberson, and webster, ), warr’s ( ) two dimensional measure of anxiety contentment and depression-enthusiasm, and daniel’s ( ) measures of affective wellbeing featuring five first order and two second order dimensions. the panas-x is a -item schedule that provides multi-item scales for state positive of joviality, self- assurance, attentiveness, and serenity and state negative affect as well as eleven emotions (fear, sadness, guilt, hostility, shyness, fatigue, surprise, joviality, self-assurance, attentiveness and serenity). arguing that context-specific measures are often more predicatively valid in the same context, levine and xu ( ) have developed a workplace measure of ten discrete emotions, including the five positive emotions of joy, pride, attentiveness, contentment, and affection (fisher, ). self-reports self-reports are increasingly used to collect daily experiences, often in combination with fisher’s emotions scales ( robinson and clore, ; grandey et al., ; sørensen, sandelands and buckner, ). ‘self reports involve relatively smaller expenses and does not demand skills that are uncommon to find among researchers’ (sørensen, ). sørensen ( ) refers to izards part | literature study on organizational aesthetics | emotions in organizations fundamental emotions form the differential emotions theory, plutchnik’s basic emotion categories and mehrabien and russell’s pad-model (pleasure, arousal, dominance). basch and fisher ( ) and fisher ( , , , ) used their job emotion scale (jes) (affection, pleasure, happiness, pride, optimism, enthusiasm, frustration, anger, disgust, unhappiness, disappointment, embarrassment and worry) for categorize emotions after collecting them by using a self report. russell, weiss and mendelsohn ( ) used their developed affect grid in combination with self reports. also cohn ( ) used this combination of research methods. citing many research (like barrett, ; cutler, larsen and bunce, , diener, smith and fujita, ), (fisher, , ; waugh and fredrickson, ) concludes that ‘one-time retrospective measures of mood at work over the past week or month is not desirable, because of the bias in reporting affective phenomena after the fact’. reporting experiences within hours seems to be more reliable (fisher, ; waugh and fredrickson, ). during fisher’s study ( , ), respondents reported two weeks positive and negative affective reactions after receiving a signal (using programmed alarm watches) with random intervals five time each day. the self-reports are used for obtaining qualitative data about affective experiences. for analyzing these data, coding is an often used technique. derbaix and pahm ( ) suggested to code at least three type of affective reactions: ) affect words i.e. substantives of affective reactions (like happiness, sadness, shame, regret), ) expressions in which ‘mood’, ‘feel’ of ‘emotion’ war paired with a positive, neutral, or negative evaluation and ) statements ‘in which sometimes colorful descriptions from which it was easy to infer an affective reaction’. lilius et al. ( ) used coding in their research on compassion of work. they distinguished three categories: giving material support, giving emotional support and giving time and flexibility. the used a second coding iteration to indentify categories of positive meaning that people derived inferences about oneself, inferences about others and inferences about their workplace. verbal self report (vesr) another technique for acquiring data about affective emotions is the verbal self report (vesr). according to sørensen ( ), ‘this method can be applied in experimental design, in questionnaires and in interviews’. research was conducted using open ended questions or a battery of emotion measured by semantic differential or likert scales. visual self report (visr) ‘the visual self report has a lot in common with the vesr technique’, sørensen ( ) argues. instead of using emotion words, the emotions are represented by cartoon-like figures of ‘smileys’. de most used are the self assessment manikin (sam) of lang ( ), adsam of morris et al. ( ) and premo (desmet, ). other mentioned techniques for measuring emotions are autonomic measures, facial expressions, electrodermal reaction, cardio vascular responses, eye-tracking an brain imaging (sørensen, ). these techniques seems to be not suitable for this dissertation because of the complex data analysis, the relatively high measurement costs, the required knowledge to the researcher, the high investment in special equipment and the requirement of conducting the research in a laboratory. part | literature study on organizational aesthetics | emotions in organizations causes of positive emotions at work ‘most mentioned causes of emotions in organizations were to be found in attributes of the organization, the job, the supervisor, or other aspects of the work environment’ (fisher, ). she notices that ‘a very great deal of literature has accumulated showing which aspects of organizations and jobs are most often predictive of job satisfaction, organizational commitment, and other forms of emotions at work’. great place to work distinguishes trust in the employer, built on credibility, respect, and fairness as the cornerstone for a ‘great place’. sirota, mischkind and meltzer ( ) agree that equity (respectful and dignified treatment, fairness, security), achievement (pride in the company, empowerment, feedback, job challenge), and camaraderie with team mates are critical in producing a happy and enthusiastic workforce. fisher concludes that ‘high performance work practices may act on happiness at least partly by increasing the opportunity for employees to attain frequent satisfaction of the three basic human needs posited by self-determination theory: competence, autonomy, and relatedness.’ on job level, most research on positive emotions will commencement ‘when organizations has focused on stable properties of the job, with complex, challenging, and interesting work assumed to produce positive work attitudes’ (fisher, ). although developed almost forty years ago, hackman and oldham’s job characteristics (task significance, sill variety, task identity, feedback form the job and autonomy) in literature are still often mentioned as evidence confirming that jobs possessing more of these characteristics are more satisfying. and also trust in the leader is mentioned as a strong predictor of satisfaction and commitment (dirks and ferrin, ). fisher ( ) also focuses on the event level of environmental contributors. she refers to the affective events theory of weis and cropanzano ( ) which argues that ‘stable features of the work setting such as those described above act at least partly by predisposing the more frequent occurrence of particular kinds of affective events – momentary happenings that provoke concurrent moods or emotions. as predicted by affective events theory, the cumulation of momentary pleasant experiences has been shown to predict overall job satisfaction’ (fisher, , ). based on the well known research of herzberg, mausner, and snyderman ( ) in which they asked employees to describe a time they felt especially good or bad about their job, can be concluded that causing good feelings tended to differ from those associated with bad feelings. ‘good feelings were most often experienced in connection with events involving achievement, recognition, interesting and challenging work, responsibility, and advancement/growth’ (fisher, ). more recent studies of events fisher ( ) examined, showed that positive emotions at work confirm that events involving goal achievement, recognition, challenging and interesting tasks, and pleasant interactions with others are associated with concurrent pleasant emotions, and that events perceived as hassles which cause negative feelings do tend to be different than the mere absence of events perceived as uplifts (basch and fisher, , ; hart, wearing, and headley, ; maybery, jones-ellis, neale, and arentz, ). according to fisher, ‘perceived performance is likely to be another determinant of momentary positive mood and emotions at work’. fisher states: ‘employees spend most of their work time performing or attempting to perform, so beliefs about how well they are doing it should be both salient and continuously available. we know that goal achievement and positive feedback predict satisfaction (kluger and denisi, ; kluger, lewinsohn, and aiello, ; locke, cartledge, and knerr, ).’ fisher argued that perceived performance is a strong determinant of concurrent mood and emotion at work, especially for individuals ‘who care about their job and who have adopted approach goals’ (fisher, ). in an experience sampling study, she found an average within person correlation between self-rated performance at a moment in time and concurrent task satisfaction of . (fisher and noble ). about the contribution of organization features to emotions of employees, fisher mentions that ‘it is important to remember that positive attitudes are not directly created by environments or events such as those described above, but rather by individuals’ perceptions, interpretations, and appraisals part | literature study on organizational aesthetics | emotions in organizations of those environments and events’. she refers to the large body of research on appraisal theories of emotion (citing lazarus, ; scherer, schorr, and johnstone, ) clearly supports a critical role for the appraisal process in determining experienced emotion. ‘appraisals can be influenced not just by the objective nature of the events, but also by dispositional characteristics, expectations, attributions, and social influence’. a number of studies, she argues, ‘have shown that respondents’ job satisfaction and perceptions of job characteristics can be influenced by the judgments expressed by their coworkers and supervisors’ (citing salancik and pfeffer, ; thomas and griffin, ). about the personal contributors to emotions, fisher notices that ‘it seems that genes and personality explain some of the person level variance in happiness, with some individuals being naturally programmed to be happier than others’ (diener, et al., ; lucas, ). another insight of personal contributors to emotions fisher mentions, is that ‘individuals high on trait positive affectivity appear to be more sensitive and reactive to potentially rewarding situations and respond with greater increases in pleasant feelings, while those high on negative affectivity respond with stronger negative emotions in potentially punishing situations.’ the mechanisms by which dispositions contribute to positive emotions at work have been explored by several scholars (fisher, ). bowling , beehr, wagner, and libkuman ( ) propose three mechanisms: dispositions ) influence employees' equilibrium or adaptation level of job satisfaction, ) influence employees' sensitivity to workplace events, and ) influence the speed at which job satisfaction returns to equilibrium after one is exposed to a workplace event. also other researchers showed that the effects of trait affectivity on job satisfaction are mediated by state affect (ilies and judge, ; weiss ). the last research result fisher mentions is that individuals high in core self evaluations are more likely to adopt self-concordant, intrinsic goals, the pursuit of which brings happiness (citing judge, bono, erezand locke, ). interaction with others also influences the type and intension of an emotion. ‘in most areas of psychology, neither the person nor the situation absolutely determines outcomes, but an interaction between the two is important’, fisher says. the ‘fit’ or ‘need satisfaction´ theories suggest that a positive emotion occurs when what the situation offers corresponds to what a particular individual needs, wants, or expects. consequences of positive emotions at work fisher ( ) concludes that there is evidence that the experience of happiness at the transient, person, and unit level has important consequences in organizations. for underpinning her statement she refers to several studies on the topic. more specific, recent research has shown that positive emotions significantly enhance affective commitment (vianello, galliani and haidt, ; herrback, ; thoresen et al., ; fisher, ). in sum: consequences on personal level at the day level, state positive mood is associated with creativity and proactivity on the same day and predicts creativity and proactivity the next day (amabile, barsade, mueller, and staw, ; fritz and sonnentag, ; cohn, ). positive mood also seems to reduce interpersonal conflict and enhance collaborative negotiation outcomes (baron, fortin, frei, hauver, and shack, ). day level fluctuations in positive mood and job satisfaction predict daily variance in organizational citizenship and workplace deviance at the within person level (judge, scott, and ilies, ; ilies, scott, and judge, ). positive emotions promote helpful and sociable behavior towards others , reduce interpersonal conflicts and lead to a tendency towards cooperative behavior (carneval and isen, ; isen and baron, ; isen, ). part | literature study on organizational aesthetics | emotions in organizations positive emotions like joy and happiness also associated with optimistic assessments of environmental risk (lerner and keltner, ). positive meanings give rises to positive emotions, including gratitude and hope (fredrickson, ; fredrickson et al., ). positive emotions create a sense of self-worth and respect (george, ). happiness induces appraisal of certainty and perceived control over the environment, and also that people in a happy state are more likely to make risky decisions (lerner and keltner, ). people in a positive mood are more likely to adopt more creative , open, constructive and flexible cognitive processing styles (bless, ; fiedler, ; isen, , ; cohn, ). momentary positive mood can also influence how other aspects of the work environment are evaluated, with induced pleasant moods spreading to concurrent ratings of job satisfaction and task characteristics (brief, butcher and roberson, ; positive attitudes and experiences are associated with beneficial consequences for both employees and organizations. for instance, job satisfaction and kraiger, billings, and isen, ). positive moods produce more positive and optimistic attitudes about the success of the negotiation process (forgas, ). erez and isen ( ) manipulated state mood and found that positive affect increased persistence and task performance, and acted on motivation by increasing expectancies, instrumentalities, and valences. ilies and judge ( ) demonstrated that affect was an important intervening variable in explaining the effect of feedback on subsequent self-set goals. beal, weiss, barros, and macdermid ( ) suggest that all emotions, positive or negative, have the potential to reduce task performance by redirecting scarce attentional resources away from the task and toward the source of the affect. job satisfaction and organizational commitment are negatively related to intention to quit and actual turnover (griffeth, hom, and gaertner, ; meyer, stanley, herscovitch, and topolnytsky, ), absence (hackett, ; mathieu and zajac, ), and counter- productive work behavior (dalal, ), and positively related to organizational citizenship behavior/contextual performance (lepine, erez, and johnson, ). job satisfaction is negatively related to depression, anxiety, and burnout, and positively related to physical health (faragher, cass, and cooper, ). people strongly believe that happy employees are more likely to be productive employees (fisher, , ). higher order construct, overall job attitude, composed of job satisfaction and organizational commitment, is a strong predictor of a composite criterion of individual effectiveness including measures of core job performance, contextual performance, lateness, absenteeism, and turnover (harrison et al. ( ). attitudes predicted behavior more strongly when the attitudes were stable, certain, accessible, and formed on the basis of direct personal experience. job satisfaction, affective commitment, and work engagement would seem to fulfill these requirements and thus could be expected to predict appropriately matched behavioral criteria kraus ( ). compared with their less happy peers, happy people earn more money, display superior performance, and perform more helpful acts (boehm and lyubomirsky, ). happy people are less likely to experience periods of unemployment (diener et al. ) and more likely to succeed in job search. dispositional possitive affective has been linked to better performance in managerial decision making and interpersonal tasks (staw and barsade, ). the extent to which employees felt and expressed positive emotions at work predicted performance ratings, increases in pay, and social support months later (staw, sutton, and pelled, ). part | literature study on organizational aesthetics | emotions in organizations positive emotional states contribute to employee finding others more attractive (daniels and brkowitz, ; bell, ). managers high on positive affect have been found to cope with organizational change more effectively (judge, thoresen, pucikand welbourne, ). consequences on unit-level employee satisfaction touted as a possible lead indicator of later customer satisfaction and financial performance in balanced score-card approaches (heskett, sasser, and schlesinger, ; rucci, kirn, and quinn, ). unit level employee satisfaction predicts customer satisfaction and perceptions of service quality (brown and lam, ). positive emotions may lead to pleasant associations with the workplace, and through this associations, strengthen affective commitment to the organization (lillius et al., ) average employee engagement at unit level was significantly related to customer satisfaction, profit, productivity, employee turnover, and safety, with corrected population correlations ranging from . to . (harter et al., ). average organizational level job satisfaction significantly predicted subsequent return on assets and earnings per share (schneider, hanges, smith, and salvaggio, ). state positive affect does not only contribute to job satisfaction and commitment, but also to performance. in fact, lyubomirksy et al. ( ) in a recent article assessing over studies, samples comprising , participants, found that state positive affect is consistently related to performance related outcomes in cross-sectional research, longitudinal research, experimental research and field research (little, ). in sum, fisher concludes that ‘person level happiness at work is correlated with, and is often predictive of, positive consequences for both employees and organizations.’ there is evidence, she says, ‘that positive individual and collective attitudes (engagement, satisfaction, commitment, involvement) are not only related to, but also predictive of, desired outcomes including individual and unit performance, employee retention, safety, customer satisfaction, and organizational citizenship behavior (harrison et al., ; riketta, ).’ another reason to be concerned about employee emotions, according to fisher ( ), ‘is the important mediating role that attitudes and affect appear to play.’ after examining several research (carr, et al., ; mount, ilies, and johnson, ; patterson, et al., ; podsakoff, lepine and lepine, ; parker, et al. ), she concludes that ´the effects of objective work environments, job design, personality, and psychological climate on more distal outcomes such as performance, organizational citizenship behavior, and turnover are often mediated through happiness related constructs such as job satisfaction, affective commitment, and mood at work.´ giardini and frese ( ) examined the state of affect in relation to those of customers. they found positive correlations between employee pleasantness and customer pleasantness, between employee arousal and customer arousal. let’s end this paragraph with a summary statement, made by cohn ( ) in his phd dissertation: ‘when people open their hearts to positive emotions they seed their own growth in ways that transform them for the better. as such, investing time and effort to cultivate more day-to-day experiences of positive emotions not only makes modern-day humans feel better, but it also sculpts their future selves, as they become more resourceful, with better odds of success, survival, and overall well-being.’ part | literature study on organizational aesthetics | emotions in organizations concluding, positive emotions in organizations contribute to job satisfaction and commitment, and also to performance. state affect (mood) must be distinguished from emotions which are more intense, shorter lived and have definite cause. but mood must be considered as an antecedent of aesthetic experiences. employees experience nearly the full range of emotions in their workplace, as they do outside their workplace, together with emotions more specific to the work environment. negative emotions are stronger than positive emotions(‘bad events had longer lasting effects. and bad events seem to produce stronger reactions than good ones’). affective experience can be structured in two or three dimensions: a degree of pleasantness, degree of arousal and a degree of power. of these three structures, pleasantness is the most frequently found dimension of affective experience, combined with either arousal or power. in literature, three lists of emotions are dominant: first, the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix, the circumflex of watson, clark and tellegen, and third, fisher’s job emotion scale (jes). part | literature study on organizational aesthetics | emotions in organizations . affective commitment affective commitment, career commitment, continuance commitment, job involvement all represent universal forms of work commitment (carmeli and gefen, ). carmeli and gefen refer to the distinction morrow ( ) made. the term ´universal´ is meant to ´identify forms of work commitment relevant to as many employees as possible´ (morrow, ). the five universal constructs of work commitment they suggested are protestant work ethic (work ethic endorsement), career commitment, organizational commitment (continuance and affective), and job involvement. these forms are based on the five forms (protestant work ethic, career salience, job involvement, organizational commitment, and union commitment) suggested by morrow. carmeli and gefen describe the different forms as follow: ‘protestant work ethic (pwe) is the extent to which one believes that hard work is important and that leisure time and excess money are detrimental. pwe is considered a “relatively fixed attribute over the life course”. career commitment is defined as “one’s attitude toward one’s profession or vocation”. career commitment does not appear to be a particularly manipulated (changeable) attitude. continuance commitment is defined as “the extent to which employees feel committed to their organizations by virtue of the costs that they feel are associated with leaving”. in accordance with previous studies, organizational commitment is composed of two commitments, namely affective and continuance. affective commitment is “positive feelings of identification with, attachment to, and involvement in, the work organization”. employees with strong affective commitment remain because they want to. employees with strong continuance commitment remain because they need to. organizational commitment may fluctuate over an employees’ lifetime. job involvement is “a belief descriptive of the present job and tends to be a function of how much the job can satisfy one’s present needs”. it appears to demonstrate a moderate level of stability. pwe and career commitment are also relatively stable; organizational commitment can be subject to manipulation; and job involvement is moderately changeable. as discussed next, the content can determine how the five are interrelated.’ affective commitment the conception of affective commitment, the final revenue of increasing positive aesthetic experiences and decreasing negative aesthetic experiences in this dissertation, is developed by meyer and allen ( ), who has drawn from mowday’s et al. concept of commitment, in turn is a extract from the previous work of kanter ( ) (shivangulua, ). meyer and allen developed the three-component model of organizational commitment reflects a psychological state of employees as the basis for maintaining employment in an organization, that includes a desire (affective commitment), an obligation (normative commitment), and a need (continuance commitment) (liu, norcio and tsung tu, ). part | literature study on organizational aesthetics | emotions in organizations figure . the three-component model of organizational commitment (meyer and allen, ) continuance commitment is defined as ‘the commitment an employee has towards an organization because of investments they have made in the organization or the cost associated with leaving the organization.’ according to visagie ( ) ‘the distinction between affective and continuance commitment is that employees who have a high affective commitment will remain with the organization because they want to’; ‘whereas those who have a high continuance commitment will remain with the organization because they have to’ (falkenburg and schyns, ). normative commitment is a form of commitment that is based on an individual’s feeling of obligation to remain with the organization (falkenburg and schyns, ; visagie, ). an example of normative commitment (mentioned by visagie, ) is that ‘if an organization is loyal to the employee or may have supported the employees’ educational efforts, the employee may report higher degrees of normative commitment’ (williams, ). meyer and allen ( ) defined affective as ‘a positive feelings of identification with, attachment to and involvement in the work organizations.’ they refer their thinking and model on kanter’s work who defined commitment as ‘ the attachment of an individual’s fund of affectivity and emotion to the group’ (kanter, ). much earlier, kelman ( , cited by meyer and allen, ) distinguished identification and internalization categories which form the basis for commitment. ‘identification involves acceptance of influence in order to maintain a satisfying relationship; internalization involves acceptance of influence based on shared values’. ‘affective commitment is a feeling of attachment and belonging to an organization, that includes the structure of the organization, the type of work experiences, and personal characteristics’ (hartmann and bambacas, ). ‘affective commitment links employees’ emotional involvement and identification with attachment to the organization’ (tan and akhtar, ). ‘affective commitment refers to employees’ emotional attachment to, identification with, and involvement in the organization. employees with a strong degree of affective commitment continue employment with the part | literature study on organizational aesthetics | emotions in organizations organization because they want to do so’ (rahman and hanafiah, ). ‘affective commitment occurs when the employee wishes to remain with the organization because of an emotional attachment’ (spector, ). ‘affective commitment is categorized by a strong belief and acceptance of the goals and values of the organization, a willingness to put extra effort on behalf of the organizations and a desire to remain e a member of the organization’ (maxwell and steele, ; falkenburg and schyns, ). ‘this type of commitment requires a high degree of emotional identification’ (carmeli, ). table . three types of commitment (meyer and allen, ) o´reilly and chatman ( ) considered that organizational commitment has three dimensions: ) internalization (involvement predicated on congruence between organizational and individual values), ) identification (attachment based on desire for affiliation with the organization; organizational membership is incorporated in the individual’s self-concept) and ) compliance (instrumental involvement for specific rewards (herrbach, ). herrbach founds that identification strongly correlates with affective commitment and that affective commitment was significant in predicting positive activation. bagraim ( ) also develop a commitment framework is which he positions the types, antecedents and variables of commitment. the relationship of affective commitment with other outcomes of work like job satisfaction, engagement, and job performance has been examined the last three decades. mathieu and zajac ( ) in their meta-analysis of antecedents, correlates and consequences of organizational commitment presented evidence on the links between organizational commitment and a number of critical in-role behaviors, including performance, absence, lateness, and turnover (mcfarlane and wayne, ). meyer et al. ( ) repeated this study after refining their first model for organizational commitment. they extended the model with the outcomes employee health and well-being (direct related to normative commitment) and conclude after their meta-analysis that - again - the correlation between organizational commitment and affective commitment was quite strong as well as the correlation between affective commitment and job satisfaction, job involvement and occupational commitment. most empirical studies of organizational commitment have focused on affective commitment because this type of commitment is the strongest and most consistent predictor of organizational outcomes like employee retention, absenteeism, intensions to leave the organizations, customer-oriented behavior and performance (meyer et al., ; allen et al., ; meyer smith, ; rhoades et al., ; shivangulula, ; rego et al., ). other research shows that affective commitment has the strongest correlation with job performance, organizational citizenship behavior, role conflict and attendance, followed by normative commitment (meyer et al, ; witzel and tagger, ; shivangulula, ; visagie, ; cohen and kirchmeyer, ; seo et al., ). matzler et al ( ) argued that employee satisfaction is a strong predictor of affective commitment. visagie ( ) proved that affective commitment (of the three forms of commitment) has a strongest correlation with employee attitudes towards change, perceptions of training for change, need for change and organizational beneficial. vianello et al. ( ) proved strong correlation between affective part | literature study on organizational aesthetics | emotions in organizations commitment and elevation at work. one reason for the connection between affective commitment and turnover, according to mohamed, taylor and ahmad ( ), is that supportive human resource management practices signal the company's concern for the workforce. these signals elicit attitudinal and, presumably, behavioral responses such as increased commitment, continued service to the organization, and a lower intent to quit which results in lowered actual turnover (mathieu and zajac, ; meyer et al., ). carmeli ( ) argues that affective commitment positively correlates with economic prestige and with social prestige as well. meyer and allen ( ) developed a survey for measuring commitment. the items related to affective commitment are: i would be very happy to spend the rest of my career with this organization i enjoy discussing my organization with people outside it i really feel as if this organization's problems are my own i think that i could easily become as attached to another organization as i am to this one (reversed question) i do not feel like 'part of the family' at my organization (reversed question) i do not feel 'emotionally attached' to this organization (reversed question) this organization has a great deal of personal meaning for me i do not feel a strong sense of belonging to my organization (reversed question) the antecedents of affective commitment can be divided into personal characteristics, structural characteristics, job-related characteristics and work experiences (weiss and cropanzano, ; brief and weiss, ). the personal characteristics are the age of the respondent (especially seniors and new recruits), length of employment in the organizations, and the seniority (work experience) of the employee will be positively related to affective commitment (meyer et al. ). also kalderberg et al. ( ) and mathieu and zajac ( ) found positive correlation between gender and affective commitment. kaptijn ( ) investigated the antecedents of affective commitment in relation to the herzberg’s hygiene factors (herzberg, ), comfort and competence. she concludes that both factors positively correlate with affective commitment. organizational characteristics, especially physical as well as psychological conform of organizational members has been proven as employee satisfying (meyer et al. ; noe et al., ; daft, ; kaptijn, ; brook et al. ; morris and steers, ; brief and weiss, ), among leadership support , sound corporate policies and procedures, acceptable organizational structure and shared culture. kaptijn founded that ‘the effect from the mediator is large in relation to affective commitment to colleagues, where the influence from structural characteristics decreases from when the work experiences is taken into account’ (kaptijn, , p. ), . visagie ( ) suggests that affective commitment related to decentralization of decision-making and formalization of policy and procedures does exist. and also with employee-supervisor-relations, role, clarity, and feeling of personal importance, that are associated with these structural characteristics. also a shared organizational culture, which is the way organization members do things, constituting the values, assumptions, norms, understanding shared by people within an organization an taught to those joining it, assists organizational members to relate to one another and to external environment (spector, ). this, generates a sense of organizational identity and commitment, especially, affective commitment to particular values and the organization as a whole (daft, , cited by shivangulula, ). podsakoff et al. ( ) denied this results and conclude that ‘organizational structure do not have direct effect on affective commitment, but rather, that the relationship is mediated by work experiences’ (kaptijn, ). meyer and allen ( ) recognizes these difference outcomes of research part | literature study on organizational aesthetics | emotions in organizations and concluded that the comparison of studies (person-environment fit) on the role of organizational characteristics by influencing affective commitment, because ‘these studies have not used a common set of needs, values and work experiences’. brief and weiss ( ) later added work group characteristics as an antecedent of affective commitment. referring to other studies they mention common socialization experiences, and common social influences, similarity of tasks and high task interdependence, membership stability and mood regulation norms and rules the most important features of these group characteristics. work experience in this case can be divided into categories: ‘those that satisfy the employee’s need to feel comfortable in the organization (both physically and psychologically), and those that contribute to the employee’s feeling of competence in the work’ (joiner, , cited by visagie, ). according to meyer and allen ( ) ‘employee’s desire to remain with an organization will depend on the work experiences of the employee.’ ‘they will remain in membership if the organization as a result of the benefits of this relationship. work experience correlates most strong of the personal characteristics with affective commitment’ (meyer et al. ( ). eisenberg et al. ( ) introduced the concept of perceived organizational support(pos), which is based on employees' global beliefs concerning the extent to which the organization values their contributions and cares about their well-being (mcfarlane and wayne, ; rhoades, et al., ). eisenberger et al. argued that ‘employees who perceive a high level of organizational support are more likely to feel an obligation to ´repay´ the organization in terms of affective commitment’ (eisenberger et al., ) and work-related behavior (blau, ; eisenberger, fasolo, and davis-lamastro, ; eisenberger et al., ). especially the aspects organizational rewards, procedural justice (the perceived fairness of means) and supervisor support of pos have been found be positively related to affective commitment (meyer and allen, ; rhoades et al., ). ‘pos may also increase affective commitment by incorporation of organizational membership and role status into social identity’, rhoades et al. ( ) suggest . another often mentioned term related to affective commitment is organizational citizenship behavior (ocb). this type of behavior is, according to mcfarlane and wayne, ), ´is extra role behavior that is generally not considered a required duty of the job or part of a traditional job description´ (bateman and organ, ; organ, ). ´ocb includes behaviors that an individual chooses to offer or withhold without concern for immediate formal rewards or sanctions´ (ibid). several empirical studies have suggested that the relationship between commitment and ocb depends on the type of commitment examined. o'reilly and chatman ( ) stated that identification and internalization, which are conceptually similar to affective commitment, were positively related to ocb. basically, this study suggest that affective commitment will be positively, but perhaps weakly, related to ocb (mcfarlane and wayne, ). identification and representation identification and representation are often mentioned in the theory on affective commitment as well in the theory on aesthetics. identification could easily be linked to the p-o fit theory. this theory states that the congruence between characteristics of the person and those of an organization cause particular attitudes and behavior. chatman ( ) defined the person-organization fit as ‘the congruence between the norms and values of organizations and the values of persons. ’organizational norms and values are a group product’, chatman argued. ‘even though all members of the group would not have the same values, a majority of active members would agree on them and members of the group would be aware of the group's support for a given value’ she said. kristof ( ) distinguishes four levels of the environment which lead to four types of fit with a person: with the job, group, supervisor and the organization. part | literature study on organizational aesthetics | emotions in organizations meyer and allen ( ) defined affective as ‘a positive feelings of identification with, attachment to and involvement in the work organizations.’ kelman ( , cited by meyer and allen, ) distinguished identification and internalization categories which form the basis for commitment. identification involves acceptance of influence in order to maintain a satisfying relationship; internalization involves acceptance of influence based on shared values. herbach ( ) defined identification as the ‘attachment based on desire for affiliation with the organization; organizational membership is incorporated in the individual’s self-concept.’ in the theory on aesthetics identification is linked with the representation of the work of art (cooper et al., : zangwill, ; parker, ; scruton, ; mitias, ; rafaeli and vilnai-yavetz, ). one of the arguments a perceiver has positive aesthetics emotions (‘it is beautiful!’) and experiences aesthetic value is because the perceiver identifies himself with the value the art work represents. in organizations, ‘the values of an individual at work will have a direct effect on his or her behavior.’ meglino et al., ) argued. ´and, positive outcomes and affect will result when an individual's values are congruent with those of other persons or entities (e.g., a supervisor or an organization) with whom he or she is in contact.´, they added. sensemaking and value congruence one of the insights of the theory on aesthetics is that positive aesthetic experiences can be meaningful for the perceiver (mitias, ; parker, ; scruton, ; girod et al., ; csikszentmihalyi, ; beardsley, ; rafaeli and vilnai-yavetz, ). these aesthetic experiences make sense for the perceiver. sensemaking in organizations is extensively studied and described in weick’s important book ‘sensemaking in organizations’. sensemaking is, according to weick, ‘the act of constructing interpretations of ambiguous environmental stimuli’ or more simple: ‘making something sensible’. not to be understood literally, but metaphorically. ‘content is a key resource for sensemaking, of even more important is the meaning of this content’, he argues. ‘meaning depends on which contents gets joined with which context, by what connection and is embedded in cues, frames and connections’ (ibid).´ the sensemaking process goes cyclic from justification, to interpretation, to validation. the justification is based on meaning of interacts, symbols, underlying patterns (including organizational identities) and past events that cause common points of cognitive (casual) maps. interpretation is based on the meaning of reification of social and organizational roles and causal relationships, common points on cognitive maps, motivations to act and interacts that cause collective structure. ‘and validation is based on meaning of interacts that cause post decision justification and shared underlying patterns’ (de bernardis, unpublished). ‘this hermeneutical process ‘represents all of the ways in which one seeks meaning over and above their dictionary meaning and the rules of grammar’ (guillet de monthoux, ). in this process includes three core elements: enactment, selection and retention. ‘enactment is the interaction with the context, and from the interaction with the context cues are selected retrospectively as part of making sense of the interaction. the selected cues are turned into a story that is plausible in terms of identity and experiences. the story is sustained in the organization (retention) and thereby influences future enactment and se-lection processes. in other words, sense-making is when people search for meaning of the experienced, settle for plausibility and integrate the understanding in future inter-action’ (lyhne, ; rafaeli and vilnai-yavetz, ). in relation to the aesthetic experience process leder et al. ( ) offered, there are some similarities. leder et al. distinguish the following five phases: ) perceptual analysis, ) implicit memory integration (influenced by previous experiences), ) explicit classification (influenced by domain specific expertise, declarative knowledge, interest and personal taste), ) cognitive mastering (influenced by domain specific expertise, declarative knowledge, interest and personal taste) and ) evaluation. enactment takes place during the phase of perceptual analysis. than, during the second, third en fourth phase of the process, the viewer select meaningful oas (formal, representational and part | literature study on organizational aesthetics | emotions in organizations expressive / sensory properties) which are turned (in the last phase of evaluation) into an aesthetic judgment that is plausible in terms of identity and experiences (rafaeli and vilnai-yavetz, ). ‘the shared meanings must fit into the prevailing norms of interpretation’, hong and lao ( ) argued. ‘otherwise, they can not filter through the cognitive framework and be stored in the ‘collective mind‘ of the organizations’. this judgment is sustained in the commitment of the employee to the organization (retention) and thereby influences future enactment and se-lection processes. ‘people first engage in enacting the social and material world they are situated, selecting the portions of enactment they deem appropriate, and retaining them as a plausible explanation and reference for future actions’, hong and lao ( ) stated. the meaningful interpretations, the aesthetic judgment and emotions, are retained and retrieved later on for the following sensemaking cycle in other events, following weick . rafaeli and vilnai-yavetz ( ), referring to weick’s theory as well to aet, indentify three separate dimensions for analyzing sensemaking of artifacts which are instrumentality (related to tasks and goals), aesthetics (the sensory reactions to an artifact) and symbolism (the invisible set of values en assumptions). they conclude that ‘sensemaking can lead to multiple views on symbolism, instrumentality and aesthetics, and is likely to involve emotion.’ if so, following weick’s theory, it endorses the critique on aet of lindsay and little that a judgment and emotion influence the evaluation of a second event and that a new emotion may actually predict behavior better than the original felt emotion, which are not part of the aet framework. weick proposes seven properties of sensemaking, offer to apply them for aesthetic experiences as well. properties of sensemaking (weick, ) properties of aesthetic experiences grounded in identify construction aesthetic experiences, judgment and emotions are personal. people show their identity by showing their aesthetic preferences retrospective aesthetic judgment and emotions arise after experiencing enactive of sensible environments enactive of environments (‘occasions of sensemaking’) which cause positive aesthetic experiences social having aesthetic experiencing which each other (interaction) ongoing ongoing, but people get used to beauty as well as to ugliness focused on and by extracted cues having aesthetic experiences generated by the attention of aesthetic properties (extracted cues) driven by plausibility rather than accuracy driven by positive aesthetic experiences table . overview properties of sensemaking related to properties of aesthetic experiences providing experiences (events) in organizations that make sense, organizations must provide possibilities for employees for interaction with the context, which contain aesthetic properties that cause a positive aesthetic judgment and a positive emotion. ‘make people make retrospective sense of the situations in which they find themselves and their creation’ (weick, ). if so, aesthetic experiences could me also sensemaking. part | literature study on organizational aesthetics | emotions in organizations hong and lao ( ) suggest two ‘occasions for sensemaking’: ‘ ) having the opportunity to obtain the views from different participants helps broaden the top-management dominated perspective as seen in other previous studies and ) the importance of establishing an amicable organization context through high degree of transparency is highlighted’. o’reilly et al. ( ) suggest that ‘personal values of employees are important for identification for which individuals seek social groups (organizations) that give meaning and connectness.’ porter, steers, mowday, and boulian ( ) stated that commitment is a ‘strong belief in and acceptance of the organization’s goals and values, a willingness to exert considerable effort on behalf of the organization, and a definite desire to maintain organizational membership’ so, values seem to be important for feeling committed to an organization. ‘it stands to reason that a person whose personal values matched the operating values of the organization would be more committed to the organization than a person whose personal values differed from the organization’s’, finegan ( ) argued. values can be considered as ‘evaluative standards relating to work or the work environment by which individuals discern what is ‘right’ or assess the importance of preferences’ (dose, ). often used rokeach’s definition of a value is ‘the enduring belief that a specific mode of conduct or end-state of existence is personally or socially preferable to an opposite or converse mode of control’ (rokeach, ). rokeach created a list of ‘terminal’ and ‘instrumental’ values. terminal values are ‘selfsufficient end-states of existence that a person strives to achieve’ (e.g., freedom, friendship, acceptance, wisdom, beauty, feeling of achievement). (meglino and ravlin, ). a distinguishing feature of terminal values is that they are pursued for their own sake. ‘instrumental values are modes of behavior (e.g. independent, helpful, honest, competent) rather than states of existence’, megiono and ravlin explained. according to them, ‘rokeach has proposed a functional relationship between instrumental and terminal values wherein instrumental values describe behaviors that facilitate the attainment of terminal values.’ mcdonald and gandz ( ), modified rokeach’s original list for use in the organizational context. a comparison of finegan’s study ( ) shows that of the four clusters that emerged from mcdonald and gandz’s scale, three are consistent with the often used schwartz’s domains (schwartz, ), who developed a circumplex of ten values representing four domains self-enhancement (e.g. freedom and independent), achievement, preservation and openness to change. finegan ( ) argued: ‘the humanity factor mapped on to schwartz’s category of benevolence; vision mapped on to self- direction, and adherence to convention on to conformity. the bottom-line cluster of values was not found in schwartz’s analysis. schwartz’s scale included only one of the four values represented by this scale. given that schwartz’s purpose was to find universal values, it is not surprising that the cluster of bottom-line values reflecting business values was not represented. that said, an examination of schwartz’s domains also suggest additional domains (e.g. achievement), which were notably absent in mcdonald and gandz’s taxonomy, that are probably applicable to the work domain. a merging of the two taxonomies could provide a more inclusive taxonomy of higher-order work values.’ finegan ( ) found that the value profiles that predict affective commitment and normative commitment are different from those that influence continuance commitment. ‘when affective commitment was examined, most of the variance was found to be predicted by the values comprising the humanity and vision factors’ (finegan, ). the humanity factor includes the values courtesy, consideration, cooperation, fairness, forgiveness and moral integrity. the vision factor concerns the values development, initiative, creativity and openness. ‘these values are likely to be perceived positively by many people, and accordingly, respondents are also more likely to be affectively committed’, finegan founded. de clercq and fontaine ( ) confirmed these findings in their study. ‘affective commitment was highest when people who valued these things also perceived that their organization did. person–organization fit was related only to affective commitment’, finegan ends his conclusions. part | literature study on organizational aesthetics | emotions in organizations values of professionals have been examined extensively. often cited raelin ( ) argued that these values concern autonomy, expertise, sense of ethics, meaningful and challenging work, and dedication to service delivery. on the contrary, he noticed, organizational values usually emphasize control, close supervision, work standardization, and productivity. with regard to this dissertation, the values of teachers and doctors especially those of surgeons are relevant. teachers’ values have been examined by researchers like pang ( ), peterson ( ), hauser-kram and sirin ( ), park and henkin ( ), kjellin, månsson and vestman ( ) and more recent by mulford and silins ( ), kjellin and våsterås ( ), kleijnen et al. ( ), richardson and fallona ( ), and wilson ( ). ‘research into the role of values in education is primarily based from the assumption that the values of teacher affect what and how they teach’ (kjellin and våsterås, ; mulford and silins, ). a second argument for examining teachers’ values plays an important role of teachers’ feeling of commitment to the school. pang ( ) proved that cultural linkage (achievement orientation, participation and collaboration and collegiality) strongly correlates with commitment. and that bureaucratic linkage (formality and control, bureaucratic rationality) negatively correlates with commitment. they all conclude that a professional culture can be seen as ‘the values and viewpoints shared by an identifiable and homogeneous group and will form, inform and of influence parts of professional identity’ (wilson, ). peterson ( ) argues that in schools with professional learning communities, ‘the culture possesses ) a widely shared sense of purpose and values; ) norms of continuous learning and improvement; ) a commitment to and sense of responsibility for the learning of all students; ) collaborative, collegial relationships; and ) opportunities for staff reflection, collective inquiry, and sharing personal practice’. the most positive cultures value staff members, peterson argues, ‘who help lead their own development, create well-defined improvement plans, organize study groups, and learn in a variety of ways. cultures that celebrate, recognize, and support staff learning bolster professional community.’ richardson and fallona ( ) argue - and referring to other studies like those of hansen ( ), merriam ( ) and richardson an fenstermacher ( ) - that friendliness, wit, truthfulness, mildness and temperance, justice, practical wisdom, magnanimity and honor are teachers’ most important manners and virtues. mulford and silins ( ) recognize these values and complete these with respect and the believe teachers can make a difference in the classroom. kleijnen et at. ( ) distinguish in relation to teachers human relations values (cooperation, collegiality, togetherness, feedback, learning by informal contacts, introspection), open system values (dynamics, goals progress and achievement, want to learn and improve, balance between stability and change), rational goal values (agreements and compliance, choices) and internal process values (strong organization, clear duties, powers en responsibilities, transparent decision making). doctors’ values have been examined by researchers like casell et al. ( ), dickey et al. ( ), russell ( ), park and scardino ( ) and vanderpool ( ). often mentioned doctors’ values are patient ownership, compassion, service (working for the benefit of another), altruism (commitment to service), professional responsibility and trustworthiness, (the demonstration of compassion, service and altruism that earns the medical profession the trust of the public), and autonomy and intellectual challenges. dwarswaard ( ) concludes that continuity and responsibility are important professional values. continuity, she advocates, ‘is an important value or focus ‘because surgeons like clean “their own mess” and continuity is important in the transfer of a service to a colleague’. it provides a shift from individual responsibility to collective responsibility, involving teamwork, effective communication between team members, the development of a trusting relationship with colleagues and collaborative behavior are considered more important in the future. part | literature study on organizational aesthetics | emotions in organizations in the theory on affective commitment identification is linked with attachment to organizations because of its values (tan and akhtar, ; rahman and hanafiah, ; carmeli, ; herrbach, ; o'reilly and chatman, ; friedson, ; parry, ; meyer and allen, ), particularly value congruence: the match between personal values and values which the organizations represents (chatman, ). related to sensemaking or even an aspect of it considering that ‘grounded in identify construction’ is one of the sensemaking properties, is also the role of value congruence considerable. value congruence as well as the earlier mentioned organizational citizenship behavior (ocb) are based on the person-organization fit theory (p-o fit) developed by chatman. value congruence is the most frequently used operationalization of the p-o fit (kristof, ). ‘because congruency between an individuals’ values and those of an organization may be the crux of a p-o fit’, o’reilly et al. ( ) argued. chatman ( ) argued and that ‘value congruence is a significant form of fit because values are fundamental and relatively enduring’. meglinoet al. ( ) earlier proved chatman’s statement. they suggest that ‘the values of workers and their supervisors do not appreciably change over time.’ several studies of chatman on the relationship between value congruency and commitment show that there is evidence to suggest that a value fit (value congruence) between the person and the organization is related to commitment (kristof, ; finegan, ). but also individuals’ goal congruence with organization leaders and peers proofed a positive role in p-o fit (kristof, ). posner and schmidt ( ) suggest that ‘having clarity about personal values may be more important, in relation to attitudes about work and ethical practices, than being clear about organizational values.’ the theory about value congruence distinguishes a complementary and supplementary fit (muchinsky and monahan, ). with regard to the supplementary fit - switching back to values - personal values and organizational values are more or less equal. more specific, the characteristics of the organizations (culture / climate, values, goals and norms) are supplementary to the characteristics of the person (personality, values, goals and attitudes) (kristof, ). ‘the employee recognizes his or her values into the work in the organizations, is possibly even recruited because of this congruence and is encouraged to promote and flaunt this congruence. with regard to a complementary fit, organizational values and personal values are complementary’. the first type of value congruence is most used and examined in organizations. kristof-brown et al. ( ) distinguish the perceived fit and the true fit. a perceived fit concerns the perception of the fit perceived by the individual employee. ‘values are desirable phenomena’, meglino and ravlin ( ) argued. several studies (e.g. edwards, ; finegan, ; meglino and ravlin, ) warned for this type of measurement of value congruence because of the low reliability of the result and they prefer the measurement of the true fit. megilo and ravlin ( ) suggest: ‘a) having respondents complete two identical values instruments, one on themselves and the second "according to the values of the other", and b) having respondents complete a values instrument on themselves and using independent assessments to determine the values of the other on the same dimensions.’ supplementary value congruence (as an independent variable) enhances - in the most studies but not in all – positive work attitudes, the interpersonal interaction between workers and their supervisors, organizational citizenship behavior (ocb), job satisfaction, involvement and affective commitment as well, is proved in more than twenty studies (o’reilly et al. ; meglino and ravlin, ; meglino et al., ; posner and schmidt, ). in addition, meglino and ravlin ( ) mention and referring to several studies, ‘findings also indicate positive relationships with interviewer hiring recommendations and organizational hiring decisions, job choice intentions, met expectations, self-reported health, optimism about the organization's future, and adaptability.’ ‘individuals who hold the same values’, meglino et al., ( ) argue, ‘are thought to share certain aspects of cognitive processing. these similarities are presumed to foster comparable methods of classifying and interpreting environmental part | literature study on organizational aesthetics | emotions in organizations events, and a common system of communication. such qualities are essential to the success of interpersonal activities because they reduce or eliminate uncertainty, stimulus overload, and other negative features of work interactions’ (schein, ; meglino et al., ). meglino and ravlin end their review about values in organizations with a warning. ‘relatedly, although a significant number of studies has addressed both perceptions of and actual value congruence, only initial attempts have begun to logically distinguish between these two different constructs in the literature. in addition to reflecting actual value congruence, perceptions of value congruence may in part reflect efforts to appear more consistent with the values of the organization or of significant others, but may also be driven by inaccurate ideas regarding what values are, what values are important, or the actual extent of congruence that exists.´ professional commitment because of the delimitation of type of organizations to professional or knowledge-intensive organizations, a second type of commitment needs to be described. ‘a common body of knowledge, autonomy in the application of that knowledge, commitment to a specialized line of work, identification with the profession or line of work, the responsibility to society got the ethical use of specialized knowledge and collegial maintenance of performance standards are the major characteristics of a profession’ (baugh and roberts, ). professional commitment refers to person’s loyalty to the profession and the willingness to comply and propagate the values and goals of the profession (wallace, ; llapa-rodriquez et al., ). ‘professionals are prepared for their workplace in educational institutions that are separate from the workplace’. therefore, according to parry ( ), ‘their socialization to the profession begins prior to entry to the workplace where they also continue to apply the cultural values of the profession.’ ‘they initially want to share experiences of their education and sense of professional community, cultivate identification with the profession and its values’ (friedson, ; parry, ). professional commitment has also been identified as career commitment (mueller, wallace and price ), career salience (randall and cote ), occupational commitment (ritzer and trice, ; meyer et al, ), as part of work-related commitment (parry, ) and ‘cosmopolitan-local’ distinction (gouldner ), rahman and hanafiah ( ) state. sorensen and sorensen ( ) distinguishes a number of ways this construct can be defined in, which includes an individual’s identification with and involvement in the profession; commitment and dedication to the profession; and acceptance of professional ethics and goals. for example, bhat and maheshwari et al. ( ) state that ‘professionals like doctors may do well to provide healthcare out of their concern for the profession alone’. meyer and herscovitch ( ) emphasize the distinction between feeling committed to profession, to the work itself, to teams and leaders, to values and goals and to career. carson, carson and bedeian ( ) identified three dimensions of occupational entrenchment which are emotional costs, career investments costs and limitedness of career alternatives. vogus, et al. ( ) investigated the professional tenure of which two moderators of the relationship between professional tenure and mindful organizing: professional commitment climate (the collective sense of affective of emotional attachment to the profession (meyer, allen and smith, )) and professional tenure dispersion, within-workgroup variability in professional tenure. according to them, ‘when a workgroup with high professional tenure has a professional commitment climate, its members have a willingness to engage in all aspects of the job’’ (citing reason, ). ‘this professional commitment climate provides an energizing force for motivated behavior associated with greater task persistence, depth of information processing, and creativity’ (meyer et al. ). ‘they are also likely to share the target’s values and experiences self-set and assigned goals as ideals to be achieved’ (meyer et al., ) ‘and it increases altruism towards colleagues that ensures experiences and lessons learned that are shared when needed’ (herscowitch and meyer, ). part | literature study on organizational aesthetics | emotions in organizations benson and brown ( ) found that role-ambiguity, co-worker and supervisor support are three organization variables which are significant determinants of attitudinal commitment for knowledge workers. wallace ( ) argues that ‘especially the legitimacy of the criteria used in distributing rewards and autonomy in one’s work are the major determinants of professionals’ commitment to their organization’. ‘professional commitment also keeps employees open to and flexible in the face of change and fosters stronger relationships which encourages individuals to embrace their interdependence and allow them to more effectively coordinate and take advantage of the knowledge of the group’ (gittell, , cited by vogus et al., ) the relationship between organizational commitment and commitment to profession has been examined by a few researchers. baugh and roberts ( ) are proved that ‘professional commitment, which provides intrinsic job satisfaction, combined with organizational commitment posited to produce the highest level s of job satisfaction.’ they suggest that the relationship between organizational and professional commitment may be complementary rather than conflicting. ‘high professional commitment coupled with low commitment might lead to a greater sensitivity to bureaucratic obstacles, and as a result lead to reduced job satisfaction, they argue. they suggest to examine both type of commitment simultaneously for providing a better prediction of job satisfaction. rahman and hanafiah ( ) argue that ‘underlying the relationship between commitment to the organization and commitment to profession is the issue of conflict or compatibility’. ‘variations in employment settings’, they argue, ‘have often been speculated to be a determinant of the nature of the relationship between professionals’ identification with their organizations and their identification with the values and norms of their professions.’ non- professional organizations, in particular, are assumed to be more ‘bureaucratic’ than the professional organizations, wallace ( ) noticed. on the other hand, according to rahman and hanafiah, ‘it is possible that some individuals, irrespective of whether they are working in professional or non-professional organizations, may respond more as ‘professionals’ than do others’. these ‘complexities’ could result in inconsistent value systems, which, as emphasized by lachman and aranya ( ), may lead to a ‘commitment dilemma’’ (rahman and hanafiah, ). allen and smith ( ) and later parry ( ) consider a organizational-professional conflict, which is negatively related to job satisfaction and commitment of professionals; being able to practices their profession in accordance to with values of professionalism seems to be important for to professionals. for professional employees, parry ( ) concludes, ‘commitment to the organization is not directly related to professional commitment, but commitment to the organization is contingent on the workplace experiences provided by the organization. and employees give presence to their commitment to the profession and conflict between professional commitment and organizational commitment is likely to be resolved by organizational turnover intention’. he suggests that professional commitment should be at least part of the current measures of occupational commitment or even part of the measures of overall commitment in professional organizations. jauch et al. ( ) much earlier indicate that ‘organizational loyalty and professional commitment may be essentially independent such that individual may be high on organizational loyalty and professional commitment, low on both, or high on one or the other.’ part | literature study on organizational aesthetics | emotions in organizations they defined the following six items for their survey for researchers to examine their assumption: ) to make use of my knowledge and skills; ) to increase my knowledge of my field; ) to work with colleagues of high technical competence; ) to build my professional reputation; ) to work on difficult and challenging problems; ) to contribute new ideas to my field. their study confirmed their assumptions. rahman and hanafiah exposed two different views with regards to the professional commitment- organizational commitment relationship. kornhauser ( ), blau and scot ( ), scott ( ), alexander ( ), hall ( ) and howell and dorfman ( ) examined the presence of conflict between organizational and professional commitment. professional employees tend to be more committed to their profession and its values than to their employers or organizations. kallerberg and berg ( ) described the conflict between commitment to profession and commitment to organization as resembling the ‘zero-sum’ game concept, ‘whereby an increase in the level of commitment to profession, for instance, will result in a decline in commitment to organization, and vice versa’ (rahman and hanafiah, ). other authors, sorensen and sorensen ( ), miller ( ), and howell and dorfman ( ) suggested that bureaucratic organization structures result in restrictions on professional autonomy. ‘the professional and organizational-bureaucratic value systems have often been regarded as incompatible or in conflict with each other, and associated with different role orientations. while the organizational-bureaucratic value system is assumed to be characterized by values such as hierarchical control and authority, conformity to organizational goals, norms and regulations, and organizational loyalty, the professional value system is known to emphasize values such as collegiality, professional control, conformity to professional standards and goals, professional autonomy, and client orientations and loyalty’ (corwin ; lachman and aranya ). rahman and hanafiah ( ) examined the relationship between both types of commitment of scientists and conclude that the relationships between these forms of commitment are not only multi- dimensional, but also more attitudinal. in other words, they say, ‘scientists’ commitment to their profession can be expected to enhance their stay in the organization for the reasons that ‘they want and ought to do so, rather than their need to do so.’ considering these insights, several researcher like aranya, kushnir and valency ( ), hrebiniak and alutto ( ), organ and greene ( ), podsakoff, williams and todor ( ) and meyer et al. ( ) are convinced by the contra assumption that there is no inherent conflict between commitment to the profession and the organization, provided the individuals’ professional work expectations and goals are met by the employing organization. in other words, the ‘commitment dilemma’, as mentioned above, ‘is assumed to be non-existent’ (rahman and hanafiah, ). employees may have a high degree of commitment to both their employing organization and profession. ‘both forms of commitment, in other words, are assumed to be compatible or complementary to each other and may occur simultaneously’. gouldner ( ) already in when the term ‘professional’ not even was discovered, distinguished so called ‘cosmopolitans’ and ‘locals’: cosmopolitan individuals as people with a low level of loyalty to the organization and high commitment to the profession, and localist individuals as people with high commitment to the organization and low level of commitment with the profession (llapa-rodriguez et al. ). part | literature study on organizational aesthetics | emotions in organizations models for operationalizing affective emotions at work the different aspects of emotion in work and organizations like the role of organizational environment on emotional reactions, events , emotions and their revenues in terms of job satisfaction, commitment involvement or engagement particularly have been examined per topic and not in relation to each other. at least five models have tried so far to integrate the mentioned aspects in a process or framework. the five factor model of organizational virtuousness (ov) of cameron et al. ( ) and rego et al. ( ); the broaden and build model of positive emotions of fredrickson ( , ); the affective events theory (aet) of weiss and cropanzano ( ) the multi-level module of emotions in organizations of ahskanasy ( ) based on the aet framework of weiss and cropanzano, incorporates the five levels on which emotions loom in organizations . five factor model of organizational virtuousness (ov) cameron et al. ( ) and rego et al. ( ) examined the organizational virtuousness (ov) in relation to affective commitment. ‘virtuousness refers to the pursuit of the highest aspirations in the human conditions’, bright et al. ( ) stated (cited by rego et al. ). cameron et al. ( ) propose a five factor model that consists of the components ) organizational optimism, ) organizational forgiveness, ) organizational trust, ) organizational compassion and ) organizational integrity. rego et al. examined in their study the relationship between affective commitment, organizational virtuousness and affective well-being (awb). awb is according to them ‘one of the most important components of psychological well-being, or happiness.’ because happiness is valuable perse, happiness associates with higher performance and better organizational functioning and happiness is fundamental ingredient of the ‘good life and good society’. ´awb at work may lead individuals to experience work as meaningful, thus assuming work as a mission rather than as a ‘job’ which in turn makes them more affectively attached to their organization and more committed to improving organizational performance´, they argued. in their study awb strongly correlates with affective commitment. and perceptions of organizational virtuousness predict affective commitment as well. they end their article with implications for management. in order to enhance organizational virtuousness, management should care about: ) a virtuous sense of purpose in the organizational actions and policies; ) an optimistic perspective toward challenges, difficulties, and opportunities; ) a respectful and trustful way of acting; ) a high level of honesty and integrity at every organizational level; ) interpersonal relationships characterized by caring and compassion and ) the combination of high standards of performance with a culture of forgiveness and learning from mistakes. . broaden and build model for positive emotions fredrickson’s broaden and build model of positive emotions (fredrickson, , ) contends ‘that positive emotions lead to positive performance outcomes by broadening the scope of attention, cognition and action and building physical resources, intellectual resources and social resources where negative emotions narrow one’s focus’ (fredrickson, ). although this model specifically addresses emotion rather than state affect, much of the support for the model comes from research on state affect rather than discrete emotions (little, ). the model provides support for the hierarchical relationship of emotion and state affect and their effects on performance. this model have been validated many times (fredrickson, ; andreason and powers, ; jameson, ; richards and kinney, ; shaw, mann, stokes, and manevitz, ; isen, daubman, and nowicki, ; isen and daubman, ; isen, daubman, and nowicki, ; isen and daubman, ; (isen et al., ; greene and noice, ; kahn and isen, ; cohn, )), and all studies conclude that state positive affect broadens the scope of attention, cognition and action of employees part | literature study on organizational aesthetics | emotions in organizations like being more creative, producing more unusual cognitive associations or solving problems in unusual ways. little ( ) argues that ‘people experiencing positive state affect have been shown to form more positive impressions of others (citing forgas, bower, and krantz, ) while individuals experiencing negative state affect are more likely to evaluate people and situations more negatively (citing forgas and bower, ).’ according to little, two of the most widely recognized are bower’s ( ) affect priming theory and schwarz and clore’s ( ) affect-as-information model. without discussing these extensively now, could be concluded that the affect priming theory contends that affect and cognitions are linked in one’s semantic network (little, )). according to this theory, individuals will more likely assess situations as positive as their perceptions and assessment of the situation is positively biased. ‘the affect-as-information model states that when presented with a judgment of a target, individuals assess their feelings surrounding the target rather than objective information surrounding that target (little, ). thus, when people experience state positive affect, they are more likely to judge the target more positively. little ( ) concludes that to both of these theories, work events will be perceived more positively or negatively based on the state affect of the employee’. . affective events theory (aet) the affective events theory (aet) of weiss and cropanzano ( ) aspires that affect driven behaviors will be predicted by affective reactions and not cognitive evaluation or overall job satisfaction. in the paragraph about organizational commitment the model of allen and meyer ( ) will be explained. they believe that ‘organizational commitment, conceptualized as affective, normative and continuance commitment in combination, is representative of an overall attitude toward a behavior, where the behavior is maintenance of the organizational relationship.’ on this basis ‘attitude toward a target’ corresponds theoretically with ‘affective responses’ and the three categories of ‘anticipated outcomes’ (utilitarian, normative and self-identity), they argue, correspond theoretically with ‘evaluative belief structures’. ‘these five elements of the eagly and chaiken ( ) model may be viewed as antecedents to the development of the overall summary judgment, or attitude, or in this case, overall organizational commitment. seen in this way, ‘organizational commitment is an overall, summary judgment about the status of the relationship, whereas the employee’s attitude toward the target is an influencing factor, or antecedent of this summary judgment.’ (witzel and taggar, ). fisher ( ) notices that ‘affects (moods and emotions) at work has recently increased attention after decades of neglect. particular the real time affective experiences while working in the job, in contrast to positive-negative attitudinal judgments about the job’, she mentions. weiss and cropanzano ( ) recognized these findings. they are convinced by the idea that ‘employees want to remain in organizations that provide them with positive work experiences because they value these experiences and expect them to continue’ (meyer and allen, ). they developed the well validated and used affective events theory (aet), build on the earlier mentioned two models . part | literature study on organizational aesthetics | emotions in organizations figure . the affective events theory (aet) framework (weiss and cropanzano, ) ‘aet suggests that stable work environment features predispose the occurrence of difference types of events’ (fisher, ). and that the work environment directly affects job satisfaction and that affect at work (due in part of to the work environment) has an effect on job satisfaction as well. thus, argued by little ( ),’ affect-driven behaviors are behaviors that follow directly and immediately from affective experiences and are not mediated by overall attitudes. judgment-driven behaviors are behaviors that are the consequences of decision processes where one’s evaluation of one’s job is part of the decision matrix.’ ashkanasy ( ) refers to aet ‘which holds that emotional states at work are determined by occurrence or discrete work events, especially the everyday hassles and up fits that we all experience in out working lives’. the seminal contribution of aet is that, according to ashkanasy,´ for the first time in the organizational behavior literature, an attempt has been made to tackle the ongoing, temporally varying processes that underlie behavior in organizations. aet is still under development, but it is the first true multi-level model of emotions in organizations.´ fisher ( , ) later proved that the correlation between positive affective reactions and affective commitment is positive as well. according to aet, ‘affect driven behaviors will be predicted by affective reactions and not cognitive evaluation or overall job satisfaction’ (linsay, ). this behavior is judgment driven; it results from cognitive evaluations of the work environment. here, weiss and cropanzano refer to the view that an essential property of emotions is that they constitute ‘‘action tendencies’ to engage in specific forms of behavior directed towards the reversal or maintenance of the felt affective state’ (frijda, ). they complement this view with the assumption that an individual’s affective states give rise to ‘mental readiness’ or cognitive processing tendencies that influence judgment-driven behaviors. and that behavior is motivated by emotional state as being ‘affect-drive’, as opposed to ‘judgment-driven’. ‘typical negative affect-driven behaviors include emotional outbursts, sensation-seeking behaviors such as risk-taking and rule-breaking. research has shown, however, that specific emotional states lead to specific action tendencies and thus different affect-driven behavior’ (ibid). the key distinction between affect-driven and judgment-driven behavior is, elucidated by ashton- james and ashkanasy ( ), ‘that judgment-driven behavior takes place in complex and ambiguous situations that require the use of active, constructive information processing strategies.’ they continue: ‘judgment-driven behaviors are commonly, although not necessarily, strategic. that is, they purport to maintain or to facilitate adaptation to environmental demands. as such, individuals are work environment features work events affective reactions dispositions work attitude (job satisfaction) affective driven behaviors judgment driven behaviors part | literature study on organizational aesthetics | emotions in organizations motivated by the consequences of their judgment to use controlled cognition in the formulation and implementation of that decision. in addition, judgment-driven behaviors are those that require actors to perceive, to integrate, and to assess complex environmental information, and involve inferential processes that often require actors to go beyond the information given (kelly, ). ‘in the organizational environment, examples of judgment-driven, or strategic behaviors, include risk assessment, performance evaluation, economic transactions such as substantial acquisitions and mergers, and other intra-organizational negotiations with consequences for organizational performance.’ according to ashton-james and ashkanasy ( ) who adopted aet for examining affects in decision making, ‘the crux of aet is that elements of the organizational environment that are perceived to facilitate or to impair an organizational member’s progress toward workplace goals (i.e., experienced hassles or uplifts, often in response to events derived from top managers’ strategic decisions) lead to transient positive or negative affective responses.’ fisher ( ) proved that ‘helping behavior was expected to be predicted by positive affective reactions rather than by attitudes, as individuals may choose to help those around them spontaneously when a positive affective state’. using aet framework, her research proves for example the correlation between job characteristics and positive affective reactions ( . ), the correlation between positive affective reactions and affective commitment ( . ) and job satisfaction ( . ). as a result of many other studies, affective commitment correlates positively with job satisfaction ( . ). lindsay’s ( ) results, after using the same framework, show a positive correlation between positive affective reactions and job satisfaction ( . ) and organizational citizenship behaviors (. ), both result without measuring the influences of dispositions. weiss and cropanzano ( ) suggest that ‘the formation of general attitude is influenced by affective and cognitive factors independently, citing empirical evidence that affective components better predict behavior than do beliefs’ (millar and tesser, ; breckler and wiggins; , edwards, ). witzel and taggar ( ) generally expected that ‘workplace events that generate affective responses will explain more variance in an individual’s positive or negative judgments than will events that trigger evaluation of beliefs alone.’ they also suggest that ‘some events have great affective significance whereas other events trigger primarily cognitive responses that lead to an individual re-evaluating his or her beliefs about something.’ inherent in this conception of an event is the idea of change, they say, and specifically a change in what the individual is experiencing (witzel and taggar, ). a foundational distinction of aet (weiss and cropanzano, ), witzel and taggar ( ) argue, ‘in contrast to traditional belief-oriented theories of attitude, is that affective experiences in the workplace influence overall evaluative judgments independently of the influences of beliefs about the characteristics of the target, and that the affective component better predicts behavior.’ ‘affect while working varies substantially within-person over time, through average affects also varies significantly between persons’, fisher concludes. ‘the average affect while working is predicted by affective dispositions and work environment features. the average affects while working, she continues, is not a strong predictor of job satisfaction as might have been expected’. however, she ends, ‘positive affect while working does appear to be important in predicting affective commitment and spontaneous helping behavior’. part | literature study on organizational aesthetics | emotions in organizations work environment features anticipating on the antecedents of affective commitment, organizational characteristics are one of the type of antecedents. organizational characteristics, especially physical as well as psychological conform of organizational members has been proven as employee satisfying (meyer et al. ; noe et al., ; daft, ; kaptijn, ; brook et al. ; morris and steers, ), among leadership support, transparent corporate policies and procedures, acceptable organizational structure and shared culture. podsakoff et al. ( ) denied this results and conclude that organizational structure do not have direct effect on affective commitment, but rather, that the relationship is mediated by work experiences (kaptijn, ). kaptijn founded that ‘the effect from the mediator is large in relation to affective commitment to colleagues, where the influence from structural characteristics decreases from when the work experiences is taken into account’ (kaptijn, , p. ). visagie ( ) suggests that ‘affective commitment related to decentralization of decision-making and formalization of policy and procedures does exist. and also with employee-supervisor-relations, role, clarity, and feeling of personal importance, that are associated with these structural characteristics’. also a shared organizational culture, which is the way organization members do things, constituting the values, assumptions, norms, understanding shared by people within an organization an taught to those joining it, assists organizational members to relate to one another and to external environment (spector, ). ‘this generates a sense of organizational identity and commitment, especially, affective commitment to particular values and the organization as a whole’ (daft, , cited by shivangulula, ). the chapter about organization design will address more of the aspects of work environment features. events for defining ‘events’ weiss and cropanzano ( ) used two different definitions: ‘a happening, especially an important happening’ and ´something that occurs in a certain place during a particular period of time.´ without referring, they build on thoughts of pepper ( ) who much earlier speaks about an ‘aesthetic event’ existing of the following three steps: ) the given event (knowing aspect; analysis (centrifugal) by intuition (centripetal), complementary and opposite, together they are fused); ) the physical conditions underlying the given event (they are the kind of perceptions that initiate a study of the physical conditions; the physical organism (you) is a personal texture, the object is an impersonal texture: the texture of your perception of the object is a personal-impersonal texture) and ) the individual object of which the given event is usually only a partial revelation (relationship quality: commonly known as a similarity or commonly known as individuality). basch and fisher ( ) examined particularly the middle boxes in the model: affect-producing events and emotions in the workplace. they were especially interested in what job events or situations cause employees to experience specific emotions while at work. they construct an event-emotion matrix that shows the relationship between categories of job events and the corresponding emotions experienced by people. basch and fisher ( ) conclude that ‘these definitions stop short of bringing the individual perceiver into the picture’. ‘they were aspired by the cognitive appraisal theory’ (lazarus, i ). ‘this theory posits that individuals will only feel the same emotions if their appraisal of an event is the same. appraisal, evaluation and interpretation of events, rather than the events themselves, that will determine the emotion that is experienced’ (roseman, spindel, and jose, ). basch and fisher enriches weiss’s and cropanzano’s ( ) definitions of ‘events’ by stating that ‘an affective event as an incident that stimulates appraisal of and emotional reaction to a transitory or ongoing job related agent, object or occurrence’. they also conclude that only a few studies have explored specific events that might arouse affect at work. they refer to research of hart, wearing and headley ( , ), hart et al. (i ) and herzberg, mausner, and snyderman ( ). and they conclude that ‘summary measures of daily hassles (negative events) and uplifts (positive events) correlate with global job satisfaction or quality of part | literature study on organizational aesthetics | emotions in organizations life. we have no knowledge about the specific events that generate specific emotions in the workplace.´ in their research they measured organizational events or situations that caused ten specified emotions at work. therefore basch and fisher selected thirteen of the sixteen items from fisher’s ( ) job emotion scale (jes) (affection, pleasure, happiness, pride, optimism, enthusiasm, frustration, anger, disgust, unhappiness, disappointment, embarrassment and worry), because the jes was specifically constructed to tap common job related emotions. they selected six items (relief, fear, hurt, bitterness, annoyance, and sadness) from shaver et al.’s ( ) list of prototypical emotion words. the six were added because of their frequent occurrence in anecdotes and stories reported in anthropological studies and action research about emotion, according to basch and fisher. basch and fisher adopted the incident classification system suggested by bitner, booms, and tetreault ( ) for developing a preliminary classification scheme. events positive emotions experienced negative emotions experienced positive emotions . goal achievement: situations when job related targets, or goals were met % % pleasure, happiness, enthusiasm, relief, optimism and power . receiving recognition: positive feedback from managers, supervisors and work colleagues for meeting targets, performing a job to a high standard % % pleasure, happiness, pride, enthusiasm, and affection . acts of colleagues: appraised behaviors towards oneself or towards others by work colleagues % % stimulated pleasure, happiness and affection . involvement in challenging tasks: acts of people participating in different types of job or organizational activities % enthusiasm . acts of customers: appraised behaviors towards oneself or other employees by customers % % happiness and affection . interacting with customers: acts of people participating in different types of job or organizational activities % pleasure . goal progress: positive outcomes from current events that were perceived to lead towards goal achievement % pride . organizational reputation: events involving positive attributes of the company used by employees to communicate with outsiders % pride . disconfirmation of negative % feeling of relief part | literature study on organizational aesthetics | emotions in organizations events positive emotions experienced negative emotions experienced positive emotions expectations: events that disconfirmed negative expectations about job relate outcome . involvement in decision making: acts of people participating in different types of job or organizational activities % power . influence or control: attempts to influence or control work colleagues, managers and supervisors % % power . involvement in planning: acts of people participating in different types of job or organizational activities % enthusiasm . acts of management: appraised behaviours towards oneself or towards others by work managers and supervisors % % optimism . involvement in problem solving: acts of people participating in different types of job or organizational activities % power table . job emotion scale (jes) (basch and fisher, ) about the negative matrix can be stated that respondents had no trouble recalling events involving emotions such as frustration, worry, disappointment, annoyance, anger, and unhappiness. while considerably fewer events were given in response to questions on hurt, fear, and bitterness. two event categories, basch and fisher noticed, acts of colleagues and acts of management, accounted for % of events causing negative emotions. acts of colleagues and acts of management frequently cause frustration, disappointment, annoyance, anger, unhappiness, sadness, disgust, and hurt (basch and fisher, ). basch and fisher found out that ‘events that caused positive emotions were quite consistently different from those that caused negative emotions, even when the name of the event category was the same.’ the example they mention about acts of colleagues shows that ‘led to positive emotions tended to be those involving friendly, helpful, supportive, and competent behavior, while acts of colleagues associated with negative emotions involved backstabbing, refusing to carry one’s share of the load, not cooperating, and the like.’ mignonac and herrbach ( ) distinguish another list of events and divided those into positive, negative and neutral events. part | literature study on organizational aesthetics | emotions in organizations positive events negative events successfully completed a project or task , % receive praise from your supervisor , % receive praise form a coworker , % went on vacation , % receive a praise , % improvement in benefits , % receive a promotion , % receive an award or acknowledgement of achievement at work , % an unpleasant coworker left your work unit , % neutral events change in work hours or conditions , change in quality of working space , assigned undesired work or project , % a well-liked coworker left your work unit , % problems getting along with a supervisor , % problems getting along with a coworker , % personal problems interfered with work , % benefits were reduced , % denied a promotion . % received a negative performance , % denied a raise , % table . overview of positive, negative and neutral events (mignonac and herrbach, ) the percentages stand for the amount that respondents recognized this event as positive or negative. like basch and fisher ( ) did in their study, mignonac and herrbach ( ) examined the relations between the several events and the affective states at work. they first conclude that affective work events were significantly linked to affective states at work. particularly pleasure and less stronger tiredness and comfort positively correlates with positive events, particularly with the first three positive events. while anger and less stronger tiredness and anxiety positively correlates with negative events, particularly with the third, fourth and seventh event. those events (positive and negative) with the most impact are the acts with the relation with coworkers or supervisors. secondly they state that ‘the work events are only one cause of affective states among the determinants individual dispositions, life events, of the same general work environment’. and the emotions pleasure (as the only one of the list emotions of pleasure, comfort, anxiety, anger and tiredness) strongly correlates with affective commitment. another finding of mignonac and herrbach is that the correlation between positive and negative work events is insignificant. ‘it seems not to be the case that some people experience mostly positive events at work, while other individuals mostly experience negative events’, they conclude, dispositions the type and intension of the affective reactions are also influenced by personality (characteristics) and dispositions (aptitude) of the perceiver. ‘dispositions refer to the stable personality traits that predispose individuals to some affective response’ (mignonac and herrbach, ). ‘individual differences in trait affectivity like moods influences the momentary effect; those high in dispositional positive affectivity being especially responsive to potentially pleasing events in the work environment’ (fisher, , citing bolger and schilling, ; larsen and ketelaar, ). many research (barrick and mount, ; furnham et al., ; chui and kosinski, ; penley and tomaka, ; zweig and webster, ) revealed that characteristics like extraversion, neuroticism (as part of the well validated and used big five factors (mccrae and johm ; mcgrea and costa, ): agreeableness, conscientiousness and openness) have major impact on workplace outcomes. ‘extraversion and openness has been linked to positive affect while neuroticism has been linked to heightened negative affect’ (kumar and bakhshi, ). others like morris and snyder, ; steers, ; cook and wall, ; perce and dunham, ) defined a need for achievement, affiliation and autonomy, higher order need strength, personal work part | literature study on organizational aesthetics | emotions in organizations ethic, locus of control and central life interest in work as the personal characteristics which correlate with commitment. this implies that perceivers will have different reactions to the same work event. these differences reactions will lead to different types of behaviors. aet does not make predictions regarding how specific dispositions impact perceiver behavior. critique on aet research into aet is progressing, ahskanasy ( ) concludes. ´but has yet to be published extensively in the peer-reviewed literature, although results that are emerging to date (e.g. see fisher, , b; o’shea, ashkanasy, gallois and härtel, , a, b; weiss et al., ; weiss and beal, ; mathieu and zajac, ; wegge et al. ) are encouraging.´ also lubbers and colleagues ( ) found that state affect and job self-efficacy mediated the relationship between interpersonal work conflict and performance and that state affect mediated the relationship between job characteristics and performance (little, ). fisher ( ) found that positive and negative emotions related to reports of global satisfaction, supporting the emotion- attitude link in this model. nicklas and dormann ( ) using multiple measurements obtained in a diary study, proved that affective experiences in terms of state positive and state negative affect were related to state job satisfaction. grandey et al. ( ) conducted a partial test of the framework using an event-contingent sampling method. they found that positive trait affect was marginally related to positive emotions and negative trait affect was positively and significantly related to negative emotions. the composite of negative emotions was positively related to intention to leave (little, ). mignonac and herbach ( ) concludes that ‘aet for two reasons is important in the study of work setting: ) it underscores that affective events and responses in the workplace are to be ignored both theoretically and empirically, even if they were long neglected or even denied, and ) it provide a framework of how emotions can be an essential link between workplace features and employee behavior’. interestingly, aet researchers (see fisher, , b; weiss et al., ; wegge et al., ) have provided strong confirmation that job satisfaction and affect are different, albeit related constructs. they have used esm (larson and csikszentmihalyi, ), where respondents were asked to provide data on their instantaneous feelings over a set period in their workplace environment. all these studies have supported the central message of aet: emotional reactions to events at work mediate subsequent attitudinal and behavioral responses to the events. one aspect of ongoing controversy, according to ahskanasy, concerns the conceptual nature of emotions in social settings and is salient to aet. enumerating the several lists of emotions, weiss and cropanzano didn’t incorporate all the emotions which are summed up. another critique was raised by lindsay ( ). she argues that the different factors of the model like features of the organizations or dispositions are not operationalized yet. for her empirical test she used for example the big five personality traits for operationalizing dispositions. basch and fisher ( ) concluded the same and embedded several existing lists of events. lindsay also argued that other factors might contribute to the affect and judgment driven behaviors. and finally she argued, based on her quantitative research results, that some of the paths between the boxes in the model are not in the right direction. for example, she argued, ‘it may be that organizational reactions to affect driven behavior could act to influence that type of behavior in future.’ little ( ) criticizes aet because of the opinion that ‘new emotion may actually predict behavior better than the original felt emotion, which is not part of the framework. second, the framework is developed for measuring affective reactions and attitudes over time and have not addressed the immediate relationship between events, affective reactions and affect-driven behavior’. part | literature study on organizational aesthetics | emotions in organizations one of the developers of aet, howard weiss, reflected nine years later together with beal ( ) on the framework and on the critique as mentioned above. their reflection is more a repetition of their message than an adjustment of their framework or their theory. mainly, they refer to studies that agreed with the message of weiss and cropanzano. weiss states that aet was considered as a roadmap for future research. ‘it was presented as a ‘macrostructure’ for understanding emotions in the workplace. microstructures, like operationalizing events and organization characteristics ‘would develop out of focused research’, they argue. on their reflection, the especially underline that ‘satisfaction is not an emotion, but an overall evaluation of one’s job’. ‘if job satisfaction is taken as an evaluative judgment, than affect at work can be seen as an antecedent to it. and if job satisfaction is taken to have an affective component, the affect at work can be seen to be an indicator of it’, brief and weiss ( ) argued in another article in the same year. ´events are the most proximal causes of affective experiences´, they argue. but they recognized the critique of the less operationalized part of the framework by arguing that ´the variety of events is impressive´. and they recognize the role of other influences on affective commitment liken organizational justice, psychological contracts and work stress and strain. . the multi-level module of emotions in organizations after examining aet, ashkanasy ( ) indicates an important insight of the use of the framework. he said: ‘a further outcome of aet is the importance of accumulation of hassles and uplifts. thus, rather than the intensity of major events being the source of attitudes and behavior at work, according to aet, emotions are more determined by the frequency with which hassles or uplifts occur (see fisher, , a, b).’ this conclusion implies that, according to ashkanasy, ‘to in respect of negative emotions, people are more capable of handling one-off incidents than they are of dealing with ongoing hassles. a further corollary of this is that the accumulation of negative events can be offset by positive support from colleagues, friends, and family (citing grzywacz and marks, ).’ ashkanasy proposes the idea of ‘affective episodes’, ‘where it is not so much particular events that result in outcomes, but rather the accumulation of positive or negative events in an episode that determines how we feel (fisher, ).’ in addition, fredrickson ( ) refers to the “peaks” and “ends” of affective experiences, where the outcomes of affective episodes are determined respectively by two factors: ) the most intense experience; and ) the experience at the end of the episode. thus, an employee who experiences a series of setbacks may ultimately end up seeing the episode in a positive light if the episode has a positive conclusion (ashkanasy, ). ahskanasy incorporates the five levels on which emotions loom in organizations, quite similar to fisher’s emotion-related constructs, but more divided and provided of affective abstracts: . within-person: state affect, affective events, discrete emotions, mood and behaviors; . between persons: trait affectivity, affective commitment, job satisfaction, burnout and emotional intelligence; . interpersonal interactions: emotional labor, emotional exchange, displayed versus felt emotion; . groups: affective composition, emotionally intelligent groups, emotional contagion, leader- member exchange; . organizational-wide; organization policies, requirements for emotional labor, stress and wellbeing, emotional climate and culture. part | literature study on organizational aesthetics | emotions in organizations . conclusions looking back on the theory about emotions and affective commitment in organizations, and keeping the two major defined research questions in mind, the following insights could be mentioned: positive emotions in organizations contribute to job satisfaction and commitment, and also to performance. but also negative emotions influence these outcomes. they can be considered al stronger than positive emotions, so they should be avoided. employees experience nearly the full range of emotions in their workplace, as they do outside their workplace, together with emotions more specific to the work environment; in literature, three lists of emotions are dominant: first, the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix; second, the circumflex of watson, clark and tellegen ( ); and third, fisher’s ( ) job emotion scale (jes); the affective events theory (weiss and cropanzano, ) holds all the aspects (organization design, aesthetic experiences as part of affective events and the relation to affective commitment) of the research question of this dissertation, is validated and extensively supported with quantitative research results and could be constitute the framework for this dissertation; for measuring affective experiences like aesthetic experiences, a daily used self-report, possibly combined with a survey like panas-x, is a useful method for data collection; affective commitment (compared to other types of commitment) is the strongest and most consistent predictor of organizational outcomes like employee retention; affective commitment has the strongest correlation with job performance, organizational citizenship behavior, role conflict and attendance; particularly in professional or knowledge-intensive organizations, professional commitment need to be considered in addition to affective commitment; basch’s and fisher’s affective events-emotions matrix could be a useful list for categorizing events in organizations; the antecedents of affective commitment can be divided into personal characteristics, structural characteristics, job-related characteristics and work experiences. part | literature study on organizational aesthetics | conclusions conclusions an existing, validated and useful theory in which the three topics aesthetics, organization and design and affective commitment coincide is one of the major findings. this affective events theory (aet) developed by weiss and cropanzano ( ) is based on the idea that employees want to remain in organizations that provide them positive work experiences because they value these experiences and expect them to continue (meyer and allen, ). or citing ashton-james and ashkanasy ( , p. ), who adopted aet for their research like many other researchers did, ‘the crux of aet is that elements of the organizational environment that are perceived to facilitate or to impair an organizational member’s progress toward workplace goals lead to transient positive or negative affective responses.’ the theory is smoothly connected to the research model of this dissertation which was developed in the phase of proposal of this dissertation. aet is often used and well validated by quantitative and qualitative data in many studies and published in the peer-reviewed literature (e.g. see fisher, b; o’shea, ashkanasy, gallois and härtel, , ; weiss et al., ). aet is developed for a broad range of affective events, experiences and emotions in organizations. aesthetics in organizations can be considered as a specific experience with specific features and characteristics. therefore, aet is adapted in order to influence the aesthetic experiences of employees in knowledge-intensive or professional organizations through organizational design ultimately to enhance the affective commitment of these professionals. figure . the initial organizational aesthetics framework object subject (observer) properties aesthetic formal, expressive and representational properties needs motivational needs positive emotions caused by aesthetic experiences values aesthetic value function offering employees positive aesthetic experiences form organization design - organizational aesthetic stimuli (oas) - conditions for having paes/naes in work events job / work design - oas work events - oas aesthetic process aesthetic judgment - ‘beautiful work’ - ‘beautiful organization’ (paes / naes) emotions employee - gender - age - education - years of occupation - years in organization - religion - mood - aesthetic sensitivity affective commitment part | literature study on organizational aesthetics | conclusions this literature study on three topics, particularly the combination of findings, provide new insights into aesthetics in organizations. the adjustments to weiss‘s and cropanzano’s affective events theory, the addition of aesthetics, and the reasons for it are as follows. ‘environmental conditions are of paramount importance for the aesthetic experience’, csikszentmihalyi ( , p. ) stated. the unity of aesthetic properties of an object or artifact with and a perceiver in one event is what creates the aesthetic situation (mitias, ). during work, the organization forms the environment where events and aesthetic experiences take place. organizational characteristics, especially physical as well as psychological conform of organizational members has been proven as employee satisfying (meyer et al. ; noe et al., ; daft, ; kaptijn, ; brook et al. ; morris and steers, ). there fore a direct connection from organizational to design affective reactions is added from the assumption that characteristics of organizational design can lead to aesthetic experiences. as obvious in many design disciplines like product design, architecture or multimedia design, a distinction is made between aesthetic properties and non-aesthetic properties to realize aesthetic value and functional value from the user or perceiver. guillén ( ) conclude that we have long neglected the aesthetic context of organizational behavior. he refers to architects, who worked with the design principle of unity, order and purity (examples of formal properties), which should be directive for any design, according to guillén. thus, in the first block of the adapted aet, aesthetic properties are added to the characteristics of the organizational design. the use of formal (balance, harmony, unity etc.), representative (values, symbolic, historic) and expressive / sensory properties could be a possibly distinction of aesthetic properties, because this represents the most commonly found classifications of aesthetic properties. for defining the elements of the organization design, mckinsey’s -s model or weisbord’s six-box model seems to be most the fruitful models for designing organizations in which aesthetic aspects can be uncovered and embedded. the heart of the model is formed by the events taking place in the organization. kaptijn ( ) founded that ‘the effect from the mediator is large in relation to affective commitment to colleagues, where the influence from structural characteristics decreases from when the work experiences is taken into account’ (kaptijn, , p. ). the categories of affective events developed by basch and fisher ( ) initially seem very useful, complemented with typical ‘professional events’ like learning or designing. the occasional events as well as organization characteristics lead the perceiver to certain emotions. the aesthetic process will lead to aesthetic judgment (a result of the evaluation of the cognitive mastering stage) and aesthetic emotion (an emotional reaction which is a by-product of the processing stages), leder et al. ( ) claim. literature about other type of emotions (like basch and fisher, ; russell, ward and pratt, ; watson, clark and tellegen, ) combine these two results in the distinction of positive and negative emotions and pleasure and displeasure. beautiful, harmonious, elegant are often used types of aesthetic ratings or judgments a viewer might have after having an positive aesthetic experience. pleasant, exiting, arousing, happiness, joy and affection are positive emotions a perceiver might have after having this experience. the difficulty with defining judgments and type of emotions is the variety of judgments and emotions as the results of an aesthetic process and the relations between the judgment and the emotion. the most common categories of emotions earlier mentioned claim that they cover all type of emotions, divided into positive and negative emotions. it is hard to make a translation of the results of aesthetic experiences to the generic emotions. basch’s and fisher’s ( ) job emotion scale (jes), the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix, or the circumflex of watson, clark and tellegen ( ) (and linked panas-x scoring) could to make that translation could be useful instruments during field research for making this translation. the literature on aesthetics is more focused on aesthetic judgment (by the discussion on taste) than on the emotion that constitute the opinion. leder et al. ( ) talks about ‘a by-product’ of the processing stages of the aesthetic process. the question is whether a negative aesthetic judgment (for example of a painting) necessarily lead to a part | literature study on organizational aesthetics | conclusions negative emotion. the aesthetic evaluation will have little impact on the emotions of the viewer as much significance or meaning to his opinion. so possibly, the aesthetic judgment (positive versus negative) as well as the emotion (positive versus negative) after having an aesthetic experience needs to be measured. using a affect grid, like russell, weiss and mendelsohn ( ) proposed, in which the emotion as well as the aesthetic judgment of the perceiver after an events can be positioned could be useful. the dispositions in the aet framework concerning the characteristics of the perceiver. bowling, beehr, wagner, and libkuman ( ) propose three mechanisms: dispositions ) influence employees' equilibrium or adaptation level of job satisfaction, ) influence employees' sensitivity to workplace events, and ) influence the speed at which job satisfaction returns to equilibrium after one is exposed to a workplace event. also other researchers showed that the effects of trait affectivity on job satisfaction are mediated by state affect (ilies and judge, ; weiss ). from the literature on aesthetics, specific aspects of disposition could be added. experiencing aesthetics requires an aesthetic attitude and interest of the viewer or at least attention for it. and being attended by something beautiful or ugly the ability to apprehend and understand the several aesthetic properties of the object or event. also cultural background and tradition, social economical status, education, taste, personal experiences and interests with and exposure to these influence the affective reactions of the perceiver. in the right part of the model, the subject (observer) part, weiss and cropanzano in their aet model distinguish job satisfaction as the main outcome beside judgments driven behavior and affective driven behavior. most empirical studies on employee satisfaction, commitment, engagement, involvement, performance have focused on affective commitment because this type of commitment is the strongest and most consistent predictor of organizational outcomes like employee retention (meyer et al., ; allen et al., ; meyer smith, ; rhoades et al., ; shivangulula, ). other research shows that affective commitment is most strongly correlating with job performance, organizational citizenship behavior, role conflict and attendance, followed by normative commitment (meyer et al, ; witzel and tagger, ; shivangulula, ; visagie, ; cohen and kirchmeyer, ). matzler et al. ( ) argued that employee satisfaction is a strong predictor of affective commitment. visagie ( ) proved that affective commitment (of the three forms of commitment) has a strongest correlation with employee attitudes towards change, perceptions of training for change, need for change and organizational beneficial. vianello et al. ( ) proved strong correlation between affective commitment and elevation at work. considering the aspects meyer and allen ( ) mention in their developed survey for measuring commitment, many of these or strong related to the affective events weiss and cropanzano described. in paragraph and table . also the relationship between affective commitment and performance has been described. many studies show strong causality between both outcomes. but in the proposed organizational aesthetics framework only the outcome of affective commitment is showed. this is done on purpose to avoid a focus on the discussion whether attention to aesthetics contributes to performance. criticism of the theory is another criterion for deciding whether or not to adopt aet in this dissertation. in the above arguments for the use and adaptation of aet are the criticisms considered and processed. ahskanasy ( ) concerns about weiss and cropanzano didn’t incorporate all common used categories of emotions isn’t relevant in this dissertation which is primarily concerning about aesthetic experiences. lindsay’s ( ) and basch’s and fisher’s ( ) critique about the not operationalized boxes of the different factors of the model like features of the organizations or dispositions is recognized. for the more specific details of the factors of the model, the many theories and models of organization design, affective events, affective emotions and dispositions by experiencing aesthetics will be examined. for example, common models for organization design like mckinsey’s -s model or part | literature study on organizational aesthetics | conclusions weisbord’s six-box model, the categories of affective events developed by basch and fisher ( ), basch’s and fisher’s ( ) job emotion scale (jes), the russell, ward and pratt ( ) two dimensions-pleasure-displeasure and degree of arousal-denote matrix, or the circumflex of watson, clark and tellegen ( ) for defining emotions and the specific mentioned dispositions for experiencing aesthetics will enrich the model. lindsay’s second critique is about the missing of other factors that might contribute to the affect and judgment driven behaviors. her critique, quite similar to little’s ( ), based on her quantitative research results, is that some of the paths between the boxes in the model are not in the right direction. she argued that previous reactions could behavior in future an that new emotion may predict behavior better than the original felt experience, which is not part of the framework. this touches the phenomena of habituation of beauty of ugliness. examining the aesthetic experiences of employees over time, it is quite assumable that these will change, certainly with regard to positive aesthetic experiences. the aesthetic judgment and/or the emotion due to this judgment will possibly be less positive or at least less activated. when the aesthetic judgment and/or the emotion is changing over time, the affective commitment of the employee will change as well. changing and surprising, being confronted with something less beautiful is needed for re- appreciating beauty. little’s second critique on aet, that the framework is not developed for measuring affective reactions and attitudes over time which changes constantly is recognized in many contributions. for example fredrickson ( ) and later cohn et al. 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( ). towards a positive design theory: principles for designing motivating information and communication technology. advances in appreciative inquiry, vol. appendices appendices overview appendices: appendix aesthetic related terms used in organization literature appendix data empirical study : interviews organizations appendix data empirical study : ideo-research appendix correspondence respondents empirical study appendix overview characteristics of respondents empirical study appendix data empirical study : survey appreciation of oas appendix data empirical study : factor analysis survey appreciation of oas appendix data empirical study : correlation oas and revenues appendix data empirical study : survey answers open-ended questions appendix data empirical study : data canonical correlation analyses appendix data empirical study : results bel-book appendix overview of mentioned oas appendix data empirical study : returning employees appendix relation oas and revenues appendix correspondence empirical study appendix data empirical study : teachers of elementary schools appendix data empirical study : surgeons appendix data empirical study : paes professionals correlations appendix data empirical study : naes professionals correlations appendix data empirical study : overview associations formal properties professionals appendix overview data profesisonals and genral employees appendix overview questions focus of organizational aesthetics appendix invitation validation workshops appendix description validation workshops appendix data validation workshops appendix vocabulary organizational aesthetics appendices appendix : aesthetic related terms used in organization literature term or keyword number of time mentioned in literature examples of text phrases in organizational context functional** -- aesthetic -- beaut** / ugl** / elegan** / gracious / / / -- peak shift / climax / tension / power / focus / dominan** / / / / / climax of the program climax of winning tensions of organization design tensions in governance job tension creative tension power of learning power to influence mind power of the workforce organizational power processual power power to make decisions (decisional power) power structures and hierarchies power to control / regulate / coordinate power to achieve delegate power and responsibility power of computers market dominance dominance of management dominance view / perspective / dimension peak demand peak of workload peak hours isolat** employee isolation isolation from the environment activities in isolation discussed in isolation group** departmental grouping strategic grouping market grouping versus functional grouping grouping of tasks and roles grouping processes / activities grouping resources grouping functions / specialists / disciplines search abi / inform: and “organization design” or “organizational design” or “design parameters”, document text, sources since / / in journal of management, the journal of management studies, international journal of management reviews, organization studies, the journal of business strategy, international journal of business and management science. appendices term or keyword number of time mentioned in literature examples of text phrases in organizational context grouping strategic areas grouping problems grouping data contrast / variety / contrast in behavior variety of people variety of environments variety of mechanisms variety of scenarios variety in organizational designs variety of language product variety variety of skills and knowledge variety of dimensions / views / perspectives variety of tasks variety of solutions variety of situational factors variety of causes problem / problem solving / problem solving symmetry symmetric effects of misfits on performance symmetry of divisions symmetry of the mission statement symmetry of hierarchy symmetric dependence generic viewpoint (‘vantage points’ / abhorrence of coincidence), from one perspective generic view of management information generic view of marketing generic view of management innovation unity / unity in variety / wholeness / / unity of command (fayol) unity of product unity of direction / unity of purpose unity of effort unity of action unity result group unity / team unity unity of language unity in disciplines and knowledge repetition / rhythm / order** / regularity / / / repetition of work (minzberg) employee skills through repetition (learning) repetition and standardization repetition numbers repetition of mistakes satisfactory rhythm in work / of daily work rhythm of change / renewal stages and rhythms of the evolution rhythm of measuring, evaluating, planning, and executing rhythmic relationship between different types of appendices term or keyword number of time mentioned in literature examples of text phrases in organizational context tasks: between easy and difficult tasks and between immersion and quick tasks short cycled rhythms rhythmic temporal pattern of interaction balanc** / harmon** / cohesion / equilibrium / impartiality / coheren** / / / / / balancing between two opposing considerations: differentiation and integration (beer) balancing demands balancing variety balanced score card balanced incentives balance between efficiency and responsiveness balance between differentiation and integration balance between increasing customer value and large-scale manufacturing and standardization harmony between structures of five (mintzberg) harmony between the staff and enterprise harmony between enterprise and society harmony between the enterprise and nature harmonious leadership harmony in relationships (social) workplace harmony in harmony with the contingency factors of the environment harmonious business relationship team cohesion (social) cohesion between organizational design and technology simpl** from complexity to simplicity simplicity of business processes simplicity in structures simplicity of solutions clarity / density / transparen** / / clarity to customers and vendors clarity in the design clarity of vision, values, and strategy clarity of information and communication density functions density of coordination networks density of performance transparent solutions transparent rules, policies and operations (process) transparency of governance structure transparency of alignment intens ** intense management challenges intense competition intense incentives intense collaboration appendices term or keyword number of time mentioned in literature examples of text phrases in organizational context intense experiences knowledge-intense intensity of rivalry complex** / dynamic / managing complexity complex relationships complex structures complex organization design complex environment complex organizational issues dynamic capabilities dynamic organization design or structure dynamic environment appendices appendix : data empirical study - interviews organizations data interviews organizations o rm it r a b o b a n k w o u d e n b e rg o o g zi e ke n h u i s r o tt e rd a m r a n d st a d k o n . h u ls h o f r o c t ilb u rg z o n m w h a rr e ve ld f le vo - zi e ke n h u is f in e xt t o t a ls a. aesthetics as a strategic starting point (trigger / critical moment) a rehousing / rebuilding x x a new management x x x x x a focus op employees (strategy change) x x x x x x a strategy based x x x x a fear reduction by patients x a want to win price (best employer / design best annual report) x x a value driven / new values x x x x x a focus on customers (strategy change) x x a focus on professional management (strategy change) x a focus on integrated thinking (management) x x a continuity x a focus on added value (to customers and to employees) (strategy change) x a focus on csr (mvo / rijnlands) (strategy change) x x x a new mission / vision / philosphy x a bad image x x a bad performance / incidents x a low employee satisfaction x a bad control cycle x a distance management-employees / access to management x a new company x a culture x b. oas / beauty carriers b interior – exterior struc x x x x x x x x x x b flexibility / dynamics syst x b people orientated management man x x x x x b product and services strat x x b influence of staff syst x x x x b contribution to society strat x x x appendices b transparancy (workprocesses, goals, strategy, behavior, building) syst x x b open culture cult x b house style struc x b personal development struc x x x x b image strat x x b consistency of organization aspects syst x x b attraction to colleagues /collegiality /cooperation cult x x b leadership (receptive, stimulating, sincere, doing extra things) man x b employ different groups in the village strat x b taking into account the various cultures cult x b contribution to society strat x x b visual communication struc x x x b processes syst x b passion of customers strat x b the fit (person - organization) staff x b small in large scale (human scale and different identities) struct x b diversity of people staff x x b organization as meeting place strat x x x b employees (competencies, attitude, ambitions) staff x x b company philosophy strat x b realizing results (that matter) strat x x b promptness in work (employees) staff x b process of change / surprise / growth cult x x b harmony (way of working together) cult x x b not routinelywork / adhoc situations syst x x b balance between tight rules -chaos (management style) syst x b contacts with customers staff x b working in teams (feedback / learning loops) struc x b chaos syst x appendices c. implementation aesthetic principles / process / conditions c leadership / involvement / conviction / sincerity / individual attention / humor x x x x x x x c creating conditions for opportunities for employees (craftsmanship) x x x c value based x x x x x c showing to customers (image) x c mirroring other organizations x x c communication about aesthetics x c focus on identity / image x x x c continiously attention for beauty c csr (mvo / planetree / rijnlands) related x x x c good economic business situation x c sensitivity and attitude of management x c definition of what is beautiful / ugly x c cooperation employees - management x x x x c continue to suprise / wonder x x c recruitment and selection of people (good fit) x x c informal culture (space for being different) x x c dialogue with employees x x x c learning conditions x x c employee responsibility x x c hr-tools x c willing to change staff (attitude 'can in be otherwise?') x c continouity x d. revenues of organizational aesthetics d good image x x x x x x d award (high ranking on list 'good werkgever' / architecture price / best design annual report) x x x d high customer satisfaction x x x x x x d positive feedback from environment x x x x x d influx of new employees x x d high employee commitment x x x x x x d good financial results x x d nicer work x d proud employees x x x x x x d relaxed employees x d low absenteeism x x d high brand equity x d appreciation (collegiality) of staff x x x appendices d internal growth of staff x d solidarity of emplyees x x d work pleasure (emplsatis) x x x d ownership of the company (by staff) x x x d identification of employees with organization x d better cooperation (of employees) x d better control cycle x d more autonomy of management x d less meetings x d flow / 'game moments' x x d nice working climate (culture) x x d sensegiving x organization characteristics (type of business, number of employees, contact) ormit trainee development, fte, nick hoogendoorn (manager hr) rabobank woudenberg banking, fte, danielle van geest (communication & marketing) oogziekenhuis rotterdam hospital, fte, kees sol (director) randstad employment, . fte, wim vos (design manager) & karen maclaine (management development) koninklijke hulshof tannery (leather), fte, herman hulshof (director) roc tilburg education, fte, carl govers (director) zonmw research, fte, marjolijn mercx (hr) & henk smid (director) harreveld youth care, fte on locations, jan willem bedeaux (director) flevo-ziekenhuis hospital, fte, tim winkler (director quality, hr & education) finext consulting, fte, fokke wijnstra (senior consultant) appendices appendix : data empirical study - ideo-research oas in ideo-blog total mentioned staff employees (competencies, attitude, ambitions) ( ) diversity of people ( ) values of people* (honest, integrity) the fit (person - organization) ( ) promptness in work ( ) contacts with customers mana- gement leadership ( ) support of management people orientated management / taking into account the various cultures ( ) speed and levels of decision* possibilities of new ideas / innovation system flexibility / dynamics / not routinelywork / adhoc situations / chaos ( ) involvement in innovation process* total and consistency of organization aspects (completeness, a whole, unity, pattern, symmetry) ( ) simplicity of realizing goals* processes (clean, lean, efficient) influence of staff ( ) balance between tight rules -chaos (management style) ( ) autonomy / independence self-organization / emergence* internal communication transparancy / clarity (workprocesses, goals, strategy, behavior, building) ( ) structure interior / exterior ( ) house style / visual communication ( ) flat structure, no hierarchy* development opportunities / personal development ( ) organization size ( small in large scale (human scale) working in teams (feedback / learning loops) ( ) strategy product and services ( ) contribution to society ( ) employ different groups in the village ( ) passion of customers ( ) image / brand ( ) company philosophy ( ) realizing results ( ) responsive and engagement with environment* appendices oas in ideo-blog total mentioned organization as meeting place ( ) clarity about contribution employees of overall purposes* culture culture openess of org (open culture) process of change / suprise / growth ( ) collegiality / cooperation / harmony (way of working together ( ) involvement / solidarity collegeaques ( ) * = new in comparison with list oas of managers (study ) () = mentioned on list oas of managers (study ) appendices appendix : correspondence respondents empirical study ormit mevrouw h.c. van ee dorpsstraat hh de bilt uw kenmerk ons kenmerk doorkiesnummer datum sdg/msp/ /oo - februari onderwerp inschrijfformulier geachte mevrouw van ee, uw organisatie heeft interesse getoond in de deelname aan de wedstrijd ‘mooiste organisatie van nederland’. daar zijn we erg blij mee. de jury van deze wedstrijd heeft besloten om de wedstrijd te veranderen in de ontwikkeling van een lijst van ‘mooie organisaties’. organisaties die zich aanmelden komen in willekeurige volgorde op deze lijst te staan en ontvangen een oorkonde ‘mooie organisatie ’, mits hun scores op de in te vullen vragenlijsten daartoe aanleiding geven. om in aanmerking te komen voor deze vorm van onderscheiding, blijft de procedure gelden, die is beschreven in de aan u toegestuurde informatie. dat wil zeggen dat uw organisatie meewerkt aan de steekproef en het betreffende aantal vragenlijsten laat invullen door de medewerkers van uw organisatie. u kunt de deelname van uw organisatie bevestigen door het bijgaande inschrijfformulier in te vullen en voor maart aanstaande te retourneren naar het onderstaand adres. u kunt daarvoor gebruik maken van de bijgevoegde antwoordenvelop. mocht u vragen hebben, dan kunt u mij bellen op telefoonnummer - of op - . met vriendelijke groet, namens het genootschap ter bevordering van schoonheid in organisaties, iva steven de groot senior onderzoeker appendices appendix : overview characteristics of respondents empirical study tandarts verhoeve umcg zonmw rabobank ormit organisatieomvang aantal benaderd aantal respondenten (n=) % respons % % % % % geslacht % % % % % man % % % % % vrouw % % % % % totaal % % % % % leeftijd % % % % % - jaar % % % % % - jaar % % % % % - jaar % % % % % > jaar % % % % % totaal % % % % % geloofsovertuiging % % % % % jodendom of christendom % % % % % islam, hindoeïsme of boeddhisme % % % % % anders % % % % % geen % % % % % totaal % % % % % aantal jaar in dienst bij huidige werkgevende organisatie % % % % % - jaar % % % % % - jaar % % % % % - jaar % % % % % > jaar % % % % % totaal % % % % % hoogst genoten opleidingsniveau % % % % % lbo % % % % % appendices mbo % % % % % hbo % % % % % wo % % % % % totaal % % % % % leidinggevende functie % % % % % ja % % % % % nee % % % % % totaal % % % % % scores on oas per personal characteristics appendices data cluster analysis descriptives n mean std. deviation std. error % confidence interval for mean min max lower bound upper bound v . . . . . . . . . . total . . . . . v . . . . . . . . . . total . . . . . v . . . . . . . . . . total . . . . . v . . . . . . . . . . total . . . . . v . . . . . . . . . . total . . . . . v . . . . . . . . . . total . . . . . a . . . . . . . . . . total . . . . . a . . . . . . . . . . total . . . . . a . . . . . . . . . . total . . . . . a . . . . . . . . . . total . . . . . a . . . . . . . . . . total . . . . . b . . . . . . . . . . total . . . . . b . . . . . appendices descriptives n mean std. deviation std. error % confidence interval for mean min max lower bound upper bound . . . . . total . . . . . b . . . . . . . . . . total . . . . . b . . . . . . . . . . total . . . . . b . . . . . . . . . . total . . . . . c . . . . . . . . . . total . . . . . c . . . . . . . . . . total . . . . . c . . . . . . . . . . total . . . . . c . . . . . . . . . . total . . . . . c . . . . . . . . . . total . . . . . d . . . . . . . . . . total . . . . . d . . . . . . . . . . total . . . . . d . . . . . . . . . . total . . . . . d . . . . . . . . . . total . . . . . appendices descriptives n mean std. deviation std. error % confidence interval for mean min max lower bound upper bound d . . . . . . . . . . total . . . . . e . . . . . . . . . . total . . . . . e . . . . . . . . . . total . . . . . e . . . . . . . . . . total . . . . . e . . . . . . . . . . total . . . . . e . . . . . . . . . . total . . . . . e . . . . . . . . . . total . . . . . f . . . . . . . . . . total . . . . . f . . . . . . . . . . total . . . . . f . . . . . . . . . . total . . . . . f . . . . . . . . . . total . . . . . f . . . . . . . . . . total . . . . . appendices appendices appendices appendix : data empirical study - survey appreciation of oas ormit rabo umcg tandarts verhoeve zonmw totals oas g e m n s td g e m n s td g e m n s td g e m n s td g e m n s td g e m n s td a the people of our organization have beautiful qualities , , , , , , , , , , , , a we have a beautiful composition of employees , , , , , , , , , , , , a the people have a bad work attitude* , , , , , , , , , , , , a it is wonderful how much attention we have for craftsmanship , , , , , , , , , , , , a it is nice what the people want to achieve (their aspirations) , , , , , , , , , , , , b our management has beautiful qualities , , , , , , , , , , , , b our organization is managed beautifully , , , , , , , , , , , , b there are great challenges offered , , , , , , , , , , , , b it is wonderful there is so much attention to new ideas , , , , , , , , , , , , appendices b there is a nice balance between what the organizations wants and what the employee wants to achieve , , , , , , , , , , , , c it is wonderful how all activities in our organizations are aligned , , , , , , , , , , , , c our house style is ugly* , , , , , , , , , , , , c it is wonderful how much freedom we have to decide how to do we perform our work , , , , , , , , , , , , c it is amazing how we are informed about what is happening in our organization , , , , , , , , , , , , c there is good alignment between management and employees , , , , , , , , , , , , d we have a good business approach (‘this is how we work here’) , , , , , , , , , , , , d we have beautiful rituals like ceremonies, language, manners and jokes , , , , , , , , , , , , d we have a great attitude towards our environment , , , , , , , , , , , , d it is nice to see how we all work towards the same goals , , , , , , , , , , , , d we have a nice working atmosphere in our organization , , , , , , , , , , , , appendices e we deliver beautiful products and / or services , , , , , , , , , , , , e we have an ugly image* , , , , , , , , , , , , e we have a beautiful mission statement , , , , , , , , , , , , e we want to achieve great goals , , , , , , , , , , , , e we provide a great contribution to society , , , , , , , , , , , , e we have excellent contacts with our environment , , , , , , , , , , , , f my workplace is ugly* , , , , , , , , , , , , f the interior or decoration of my work environment is beautiful , , , , , , , , , , , , f our (internal) cooperation is beautiful , , , , , , , , , , , , f the organization offers me great opportunities for my development and deployment , , , , , , , , , , , , f it is nice to see that everything in my organization is nicely in balance , , , , , , , , , , , h , g the people in our organization have attention to beautiful things , , , , , , , , , , , , appendices g management has sufficient attention to beauty in our organization , , , , , , , , , , , , g i am regularly ‘in flow’; the sense of a great day when everything goes well in my work , , , , , , , , , , , , g i have beautiful work , , , , , , , , , , , , g i am not proud on my organization* , , , , , , , , , , , , g i daily experience fun in my work , , , , , , , , , , , , g the focus on beauty in my organization will provide better performance , , , , , , , , , , , , g appreciation (score) of beauty in my organization , , , , , , , , , , , , *= reversed question. = totally agree, = totally disagree appendices appendix : data empirical study - factor analysis appendices appendices appendices appendices appendices appendices appendices appendices appendix : data empirical study - correlation oas and revenues organizational aesthetic stimuli (oas) a a a a a b b b b b b c c c c d d d d d e e e e e e f f f f f g g g g g a de medewerkers in onze organisatie hebben mooie kwaliteiten , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , a wij hebben een prachtige samenstelling van medewerkers in onze organisatie , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , a de mensen in onze organisatie hebben een mooie werkinstelling , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , a het is schitterend hoeveel oog wij hebben voor vakmanschap van ons werk , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , a het is mooi wat de medewerkers in onze organisatie willen bereiken (hun ambities) , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , b de leiding in onze organisatie heeft mooie kwaliteiten , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , b in onze organisatie wordt prachtig leiding gegeven , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , b mij worden mooie uitdagingen geboden in mijn werk , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , b het is mooi dat in onze organisatie zoveel aandacht is voor nieuwe ideeën , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , b er is in onze organisatie een mooi evenwicht tussen wat de organisatie wil en wat individuele medewerkers willen bereiken , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , b het is prachtig hoe alle activiteiten in onze organisatie op elkaar zijn afgestemd , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , c onze huisstijl is mooi , , , , , , , , , , , , , * , , , , , , , , , , , , , , , , , , , , , , , c het is prachtig hoeveel vrijheid wij hebben om zelf te bepalen hoe wij ons werk uitvoeren , , , , , , , , , , , , * , , , , , , , , , , , , , , , , , , , , , , , * , appendices organizational aesthetic stimuli (oas) a a a a a b b b b b b c c c c d d d d d e e e e e e f f f f f g g g g g c het is prachtig hoe wij geïnformeerd worden over wat er speelt in de organisatie , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , c er is een mooie afstemming tussen het management en de medewerkers , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , d wij hebben mooie bedrijfsopvattingen(`zo werken wij hier`) , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , d wij hebben prachtige rituelen zoals ceremonies, taal, grappen en omgangsvormen , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , d wij hebben een mooie houding naar onze omgeving , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , d het is mooi om te zien hoe wij met z`n allen werken aan dezelfde doelen , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , d wij hebben een mooie werksfeer in onze organisatie , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , e wij leveren schitterende producten en/of diensten , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , e mensen (buiten de organisatie) hebben een mooi beeld van onze organisatie , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , * e onze missie is prachtig(waarom onze organisatie bestaat) , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , e wij willen schitterende doelen bereiken met onze organisatie , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , e wij leveren een mooie bijdrage aan de samenleving , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , e wij hebben prachtige contacten met onze omgeving , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , f mijn werkplek is mooi , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , f de inrichting of aankleding van mijn werkomgeving is prachtig , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , appendices organizational aesthetic stimuli (oas) a a a a a b b b b b b c c c c d d d d d e e e e e e f f f f f g g g g g f er wordt prachtig samengewerkt in onze organisatie , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , f de organisatie biedt mij mooie kansen voor mijn ontwikkeling en ontplooiing , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , f het is mooi om te ervaren dat alles in mijn organisatie met elkaar te maken heeft of mooi in evenwicht is , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , g rapportcijfer `schoonheid in mijn organisatie` , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , g ik heb prachtig werk , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , g ik ben regelmatig `in flow`; het gevoel van een topdag waarop alles vanzelf en goed gaat in mijn werk , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , g ik ben trots op onze organisatie , , , , , , , , , , , , , * , , , , , , , , , , , , , , , , , , , , , , , g ik beleef dagelijks veel plezier tijdens mijn werk , , , , , , , , , , , , , , , , , , , , , , * , , , , , , , , , , , , , , g aandacht voor esthetiek draagt bij aan prestaties , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , appendices appendices appendix : data empirical study - answers open-ended questions beautiful in my work or organization organization design parameter aspect ormit (n= ) rabobank woudenberg (n= ) umcg (n= ) tandarts verhoeve (n= ) zonmw (n= ) total (n= ) staff . my colleagues (competencies , passion, work attitude, ambition) (n) (n) (n) (n) (n) . goal realization management . challenges / opportunities in my work . support of management . possibility of new ideas / innovation system . autonomy . independence . flexibility / dynamics . variety of work . internal communicatio n . influence of staff . my work . planning cycle structure . development opportunities . my workplace / interior / exterior . collegiality / cooperation . division of labour strategy . our goals / strategy . our products / appendices services . our mission / vision . contribution to society . contacts with other stakeholders . contacts with clients . our image culture . our culture . openness of the organization . involvement / solidarity colleagues other . other (once mentioned) total appendices ugly in my work or organization organization design parameter aspect ormit rabobank woudenb erg umcg tandart s verhoev e zonm w total staff . attitude of colleagues* . staff composition management . less challenges / opportunities in my work* . less support of management * . focus on finance / cuts . professionalis m management (‘vriendjes politiek’) / management style . inertia and quality of decisions . contact with / access to management . attitude of management / hierarchy . continuous change system . autonomy . independenc e* (rules bureaucracy / working pressure) . inflexibility* . low salary / salary differences . less variety appendices of work* . less influence of staff* . low transparency (processes, policy) . internal communicati on* . my work* (high travel / lot of administrativ e work) structure . bad development opportunities * . my workplace / interior* . time for contact with colleagues* internal concurrence . not supporting ict / tools . too much layers of management . division of labour* . organization size strategy . contacts with other stakeholders * . our goals / strategy* . less contacts with clients* . bad image* . low contribution to society* appendices culture . our culture* . low involvement / solidarity* other . other (once mentioned) *aspect also mentioned as beautiful total appendices appendix : data canonical correlation analyses data cca relationship aesthetic experiences & affective commitment canonical correlations , , , test that remaining correlations are zero: wilk's chi-sq df sig. , , , , , , , , , , , , proportion of variance of set- explained by its own can. var. prop var cv - , cv - , cv - , proportion of variance of set- explained by opposite can.var. prop var cv - , cv - , cv - , proportion of variance of set- explained by its own can. var. prop var cv - , cv - , cv - , proportion of variance of set- explained by opposite can. var. prop var cv - , cv - , cv - , canonical loadings for set- a , , , a , , -, a , -, , a , , , a , , , b , , , b , , , b , -, -, b , , , b , , , c , , , c , -, , c , , -, c , , , c , , , d , , , d , , , d , -, , d , -, , d , , -, e , , , e , , , e , , , e , , , e , -, , e , , , f , , , f , , , f , , , f , , -, f , , -, canonical loadings for set- g , , -, g , , , g , -, -, appendices data cca relationship aesthetic experiences & aesthetic value canonical correlations , , , test that remaining correlations are zero: wilk's chi-sq df sig. , , , , , , , , , , , , proportion of variance of set- explained by its own can. var. prop var cv - , cv - , cv - , proportion of variance of set- explained by opposite can.var. prop var cv - , cv - , cv - , proportion of variance of set- explained by its own can. var. prop var cv - , cv - , cv - , proportion of variance of set- explained by opposite can. var. prop var cv - , cv - , cv - , canonical loadings for set- a , , -, a , , , a , -, -, a , , -, a , , , b , , -, b , , -, b , -, , b , , -, b , , -, c , , -, c , -, -, c , , , c , , -, c , , -, d , , -, d , , -, d , -, -, d , -, -, d , , , e , , -, e , , -, e , , -, e , , -, e , -, -, e , , -, f , , -, f , , -, f , , -, f , , , f , , , canonical loadings for set- g , , , g , , -, o , -, , appendices appendix : data empirical study - results bel-book categories of events (basch and fisher, ) vtspn vtspn vtspn interzin aps lei (wur) t o tl a n u m b e r m e n ti o n e d b y o rg n is a ti o n s ) goal achievement ) receive recognition ) acts of colleagues ) involvement in challenging tasks / opportunities ) acts of customers ) interacting with customers ) goal progress ) organizational reputation ) disconfirmation of negative expectations ) involvement in decision making ) influence or control ) involvement in planning ) acts of management ) other added events ) learning, intellectual challenge, be surprised and come to an understanding ) stimulus of physical environment conditions for aesthetic experiences (events) conditions r e sp o n d e n t r a n k in g s tr u ct u u r s tr a te g ie s y st e m e n m a n a g e m e n ts ti jl c u lt u u r p e rs o n e e l co mission and business continuity coincide x co from complete tot simplicity: from drain to ict suppliers with excess x co convert to core competences x co taking tasks seriously (deal is a deal), the aspects like finances and logistics x x co beauty as the basis of action add to the mission x appendices co the will to find the options for looking at aesthetic conditions x co the space (autonomy) for informal contact with colleagues x co the psychological state, to find some abstraction x x co a certain amount of training (learning to see what 'beautiful' can be called / can be experienced) x x co the willto work togetherto pursueagoalandsendthisandcorrect x x co freedom (autonomy) x co appeal of content while maintaining relationships x co development opportunities ? x co proud culture and humor x co freedom / mental space (autonomy) x co development opportunities ? x co management x co cooperation ? co atmosphere (culture) x co freedom with regard to substantive focus and way of working x co relevance to our work attached by others x co feedback in order to learn x x co short and relevant lines between researchers, managers and support x co intellectual challenge x co space (autonomy) for making own choices x co time for not competitive work ? x co supporting quality, various "profiles" of employees x co the feeling of working together for ‘a good thing’ x co space (mental) voor creativity x totals appendices most mentioned conditions autonomy (co , co , co , co , co ) cooperation (co , co , co , co , co ) development oppertunities (co , co , co ) respondent oas in organization conditions oas in events b + b +b +b +other co (b )+co +c (b )+c (b ) e +e +e +e +e +e +e b + b +b + other co (b )+ co (b / b )+b e +e +e +e +e +e +e +e b +b +pride (result co (b / b )+b +co (b )+b +b e +e +e +e +e +e +e +e +e b + b +b +b (logo)+b +(int/ext)+ b b +b +co (b / b )+b +b e +e +e +e +e +e +e b +e +b +b +b b +co +c (b / e )+co +b e +e +e +e +e +e +e +e +e +e +e b +b +b +b b +co +co (b / b )+co (b /b /b )+co e +e +e +e +e +e +e +e overall (mentioned in all configuratio ns) autonomy (b ) autonomy (b ) goal achievement (e ) receive recognition (e ) acts of colleagues (e ) interacting with customers (e ) goals progress (e ) learning, intellectual challenging, be surprised and come to an understanding (e ) appendices appendix : overview of mentioned oas b. oas o rm it r a b o b a n k w o u d e n b e rg o o g zi e k e n h u is r o tt e rd a m r a n d st a d k o n . h u ls h o f r o c t il b u rg z o n m w h a rr e v e ld f le v o -z ie k e n h u is f in e x t v ts p n in te rz in a p s le i (w u r ) t a n d a rt s v e rh o e v e u m c g g e n o e m d d o o r x a a n ta l o rg ( to ta ls ) r a n k in g s ta ff b employees (competencies, attitude, ambitions) (pa) x x ( ) composition of employees x x ( ) contact with manager nw (pa) ( ) the p-o fit (person - organization) nw x ( ) contacts with customers nw (pa) x ( ) m a n a g e m e n t challenges / opportunities in my work (pa) ( ) support of management nw (pa) ( ) people orientated management nw x x x x x ( ) leadership (receptive, stimulating, authentic , doing extra things) nw x ( ) employ different groups in the village nw x ( ) possibilities of new ideas / innovation ( ) s y st e m flexibility / dynamics nw x * ( ) influence of staff (pa) nw x x x x ( ) consistency of organizationaspect s (everything is in balance) x x ( ) processes nw (pa) x ( ) balance between tight rules -chaos (management style) nw x ( ) our planning cycle nw ( ) autonomy / appendices b. oas o rm it r a b o b a n k w o u d e n b e rg o o g zi e k e n h u is r o tt e rd a m r a n d st a d k o n . h u ls h o f r o c t il b u rg z o n m w h a rr e v e ld f le v o -z ie k e n h u is f in e x t v ts p n in te rz in a p s le i (w u r ) t a n d a rt s v e rh o e v e u m c g g e n o e m d d o o r x a a n ta l o rg ( to ta ls ) r a n k in g independence (pa) ( ) variety of work nw (pa) x x x ( ) internal communication ( ) divison of labour nw ( ) chaos nw x ( ) transparancy (workprocesses, goals, strategy, behavior, building) nw x x ( ) s tr u ct u re interior / exterior x x x x x x x x x x ( ) house style / fysic communication x x ( ) development opportunities x x x x ( ) small in large scale (human scale and different identities) nw x ( ) working in teams (feedback / learning loops) nw (pa) x ( ) s tr a te g y product and services x x ( ) contribution to society x x x x x ( ) company philosophy (mission/vision) x ( ) goals / strategy ( ) image x x ( ) goal / result realization nw (pa) x x ( ) process of change / suprise / growth nw (pa) x x ( ) relevance of our work considered by others nw ( ) passion of customers nw (pa) x ( ) c u lt u re culture (culture) x x ( ) appendices b. oas o rm it r a b o b a n k w o u d e n b e rg o o g zi e k e n h u is r o tt e rd a m r a n d st a d k o n . h u ls h o f r o c t il b u rg z o n m w h a rr e v e ld f le v o -z ie k e n h u is f in e x t v ts p n in te rz in a p s le i (w u r ) t a n d a rt s v e rh o e v e u m c g g e n o e m d d o o r x a a n ta l o rg ( to ta ls ) r a n k in g openness of org (open culture) nw x ( ) collegiality / cooperation (pa) x x ( ) involvement / solidarity collegeaques nw (pa) ( ) o th e r organization as meeting place nw x x x ( ) my work nw (pa) ( ) *x = genoemd door manager in interview (x) en door aantal medewerkers ( ) in survey appendices appendix : data empirical study - returning employees resondent less beautiful at last employer (that is exchanged for previous employer) beautiful at current employer (to which is returned) respondent a reason of departure not because of ‘ugliness’ work: - nice to return to work field ( .work ) - affinity with professionals ( .work / .colleagues) - able to work independently ( . autonomy) - high quality of work and output ( .other) staff: - young people, make them aware of the world they live in ( . colleagues) strategy: - leading in the world of veterinary medicine ( . goals) - contributing to improvement of the company ( . other / strategy) - chances of public – private cooperation ( . other / strategy) structure: good facilities like research lab, buildings ( . interior) respondent b work: high degree of standardization (ub . work) style of management: - differences between people is insufficient regard and exploited (ub . less support of management) - hours (bad balance work- private) (ub . less support of management) - to little focus on development of people (ub . bad development opp.) company philosophy : fairly traditional organization (company philosophy) culture: - club feeling, like-minded people with a same view to the world (bb / ) - feeling again ‘like a fish in the water’ (dutch adage) (bb ) staff: - composition of staff: great variation, but common values, ambitions and drives (composition of staff, + bb ) work: intellectual challenge in work (bb ) style of management: - attention for ‘what brings a smile at your face, what is your passion, where do you want to pay attention to?’ (bb ) - attention for personal development (bb ) - autonomy and flexibility - style of management is related to way of working (bb ) - practice what they (management) preach (man.style) - connection of values: sincere attention to people's development, give autonomy to do the work in their own way, space for making mistakes (man.style) respondent c strategy: bound to only one travel organization (not independent) (ub ) company philosophy (vision): more strategy: independent, not bound to any travel organization, possibility to do an offer which is the best for the customer (bb ) coding based on list mentioned beautiful and ugly oas survey study (appendix ) appendices focus on finance than on customer satisfaction (ub ) culture: interval cooperation, the team (staff), alwasy supporting each other, distributed work together, knowing and respecting each others work methods (bb / ) client contact and possibility to build customer relationship (bb ) company philosophy (vision): focus on ‘what’s best for the customer’ and customer relationship (company philosophy) style of management: competent manager: ‘supports me’, develops policy (bb ) respondent d culture: way of treatment: doesn't feel welcome (ub ) interior: building and spaces does not feel fine, no central reception place (ub ) style of management:- - availability and accessibility of management (ub ) - feeling of less appreciated, ' throwaway ', or exchangeable - business focus on offering courses (ub ) evaluate mode: one-sided figure frame (work process) culture: feeling of welcome (bb ) culture: ‘i feel committed to the organization, “they are committing teachers to the organizations, we are ‘jewel in the crown’ (dutch adage), highly appreciated (bb ) location: leidseplein (in old centre amsterdam) interior:’warm’ rooms (bb ) style of management: (bb ) - feeling that there for you is taken care, service- oriented (e.g. copy work is fast controlled for you) - availability and accessibility of management ( women): doors are open, really personal contact - women, arranging conditions for teachers (e.g. ict), do something extra, you feel welcome and appreciated, high ' human interest ', reciprocal - wide interested (receptive, dialogue) evaluation mode: evaluate learner and teacher (work process / ) appendices overview less beautiful aspects last employer (employer b that is exchanged for previous employer, employer a) beautiful aspects current employer (employer a, to which is returned) x focus on finance (strategy) x company philosophy (strategy) x style of management (management style) x other x colleagues (staff) x support of management (management style) x culture (culture) x involvement / solidarity colleagues (culture) x interior / exterior x work (other) x other (mentioned once: x management style, x system, x strategy, x culture, x structure, x other main reasons for leaving to employer a respondent a new challenge (role of ceo, entrepreneurship and business aspects) respondent b new challenge (role of manager, need to work longer for one client) better fit with private life (less travel time, more time for family / young children, less hectic consulting days) respondent c bad cooperation with one colleague (in small team) bad working atmosphere respondent d respondent did not leave, but compared locations of company: style of management main reasons for returning to employer a respondent a the work content / the work field (bb ) the institute (position in the world, ambitions) (strategy) respondent b colleagues (bb ) style of management (bb - ) respondent c colleagues (bb , ‘that specific colleague was moved’) style of management (bb - ) independence of the office (strategy) respondent d respondent did not return, but compared locations of company: style of management (bb - ) appendices appendix : first relation oas and revenues relation oas - revenues based on interviews (first empirical study) d high employee commitment ormit b + + + + + + + + + + + + + + + + -> high employee commitment rabowoudenberg b + + + + + + + + + + + + + + + + + + -> high employee commitment oogzkhsrottdam b +b -> high employee commitment kon.hulshof b + + + + + -> high employee commitment zonmw b + + + + + + + + + + + + + + -> high employee commitment finext b + + + + + + + + -> high employee commitment reduction: b + + + + + + + + + + + + -> high employee commitment (mentioned x) b in alle cases d proud employees rabowoudenberg b + + + + + + + + + + + + + + + + + + -> proud employees oogzkhsrottdam b +b -> proud employees randstad b + + + + + + + -> proud employees roc tilb b + + + + + + + + + + + + -> proud employees flevozkhs b + + + + + + + + + + + -> proud employees finext b + + + + + + + + -> proud employees reduction: b + + + + + + -> proud employees (mentioned x) b in alle cases d work pleasure randstad b + + + + + + + -> work pleasure flevozkhs b + + + + + + + + + + + -> work pleasure finext b + + + + + + + + -> work pleasure reduction: b + + + + + -> work pleasure (mentioned x) b in alle cases d ownership of company randstad b + + + + + + + -> ownership of company kon.hulshof b + + + + + -> ownership of company finext b + + + + + + + + -> ownership of company appendices reduction: b + + + -> ownership of company (mentioned x) b in alle cases d apprectation by staff rabowoudenberg b + + + + + + + + + + + + + + + + + + -> appreciation by staff oogzkhsrottdam b +b -> appreciation by staff kon.hulshof b + + + + + -> appreciation by staff reduction: b + + + -> apprecation by staff (mentioned x) b in alle cases overall outcomes reduction: b + + + + (mentioned x) b genoemd in cases b people orientated management b influence of staff b variety of work b interior / exterior b development opportunities appendices appendix : correspondence empirical study sint jansdal t.a.v . dr. w.l. akkersdijk wl.akkersdijk@stjansdal.nl bunnik, februari, geachte heer akkersdijk, mijn naam is steven de groot. ik benader u in het kader van min promotie-onderzoek aan de technische universiteit eindhoven onder leiding van professor mathieu weggeman. de belangrijkste vraagstelling is wat de rol is van esthetiekbeleving in werk en organisaties van professionals. esthetiekbeleving wordt hierbij breed opgevat. we weten uit eerder onderzoek dat professionals aspecten als autonomie, samenwerken, fysieke inrichting, de doelen van hun organisatie en uitdaging als ‘mooi’ beschouwen in hun werk. we weten ook uit eerder onderzoek dat in organisaties waarin men positieve esthetische ervaringen heeft het ziekteverzuim laag is en de betrokkenheid, werkplezier, productiviteit en trots hoog is. kortom, mooie organisatie zijn vaak ook goede organisaties. als onderdeel van dit promotie-onderzoek ben ik onder andere op zoek data over esthetische beleving van professionals tijdens hun werk, in het bijzonder die van chirurgen of andere artsen. daarom vraag ik u of - artsen uit uw organisatie zijn mee zouden willen werken aan mijn promotie-onderzoek. hiervoor dienen zijn gedurende twee werkweken dagelijks een logboekje (bel-boekje: beauty experience log book) bij houden waarin zij hun negatieve en positieve schoonheidservaringen noteren. hun inspanning zal ongeveer minuten per dag bedragen. daarnaast worden zij gevraagd een vragenlijst in te vullen, wat ongeveer minuten tijd vergt. ik heb het concept bel-boekje bijgevoegd. voor het welslagen van mijn promotie-onderzoek is dit veldonderzoek van zeer groot belang. ik hoop daarom van harte dat uw organisatie wil meewerken aan dit onderzoek. mogelijk moet dan een weg via uw pando-afdeling worden bewandeld? uiteraard kunnen we spreken over andere wijzen van data-verzameling, zodat het tijdsbeslag op uw organisatie zo gering mogelijk is. anderzijds levert de (geanonimiseerde) data uw organisatie inzichten en handvatten om het ziekteverzuim, betrokkenheid, werkplezier, productiviteit en trots positief te beïnvloeden en uw organisatie nog mooier en beter te maken. uiteraard kunt u met mij contact opnemen wanneer u vragen heeft over dit onderzoek. in afwachting op uw antwoord, verblijf ik met vriendelijk groet, steven de groot - sdegroot@kultifa.nl zuster spinhovenlaan cr bunnik mailto:sdegroot@kultifa.nl appendices appendix : data empirical study - teachers of elementary schools highest scores pae teachers respondents highest judgment paes highest emotional impact paes highest judgment x emotional impact paes teacher goal achievement act of customers (students) interaction with customers (students) goal achievement interaction with customers (students) teacher act of customers (students) act of customers (students) interaction with customers (students) act of customers (students) teacher goal achievement act of customers (students) goal achievement teacher goal achievement goal achievement goal achievement teacher goal achievement goal progress goal achievement interaction with customers (students) goal progress goal progress goal progress highest scores (mean) paes teachers respondents gem highest judgment paes gem highest emotional impact paes gem highest judgment x emotional impact paes teacher involvement with planning receiving recognition interaction with customers receiving recognition teacher acts of customers goal achievement goal progress influence or control goal progress influence or control teacher goal progress interaction with colleagues interaction with colleagues teacher interaction with colleagues goal achievement influence or control interaction with colleagues teacher goal progress interaction with customers interaction with customers highest scores nae teachers respondents lowest judgment naes highest emotional impact naes highest judgment x emotional impact naes teacher goal progress interaction with customers (students) interaction with customers (students) teacher influence or control influence or control influence or control teacher influence or control influence or control influence or control teacher not-functioning ict -- not functioning ict teacher influence or control influence or control influence or control highest scores (mean) naes teachers respondents gem lowest judgment naes gem highest emotional impact naes gem highest judgment x emotional impact naes teacher goal progress interaction with colleagues acts with management teacher interaction with interaction with customers interaction with customers appendices customers teacher interaction with customers involvement with planning acts of customers interaction with customers teacher interaction with customers acts of customers goal achievement teacher influence or control influence or control influence or control top mentioned paes teachers respondents of top- paes of top- paes of top- paes of top- paes of top- paes teacher goal achievement interaction with colleagues interaction with customers (students) interaction with customers (parents of students) other (good lesson) teacher receiving recognition acts of customer (students) acts of customer (students) acts of customer (students) acts of customer (students) teacher acts of students (compliments) receiving recognition acts of students interaction of colleagues goal progress (good lesson) interaction of colleagues (compliments) receiving recognition teacher -- -- -- -- -- teacher other act of students goal achievement (no fuss) acts of students acts of students top mentioned naes teachers respondents of top- naes of top- naes of top- naes of top- naes of top- naes teacher interaction with customers (parents of students) less influence or control other (cuts of finance) acts of management low involvement with planning teacher acts of management goal progress acts of customer (students) less influence or control acts of colleagues teacher loosing patience (own behavior) no control (poor preparation) act of colleagues (work ethic) act of colleagues (work ethic) acts of students teacher -- -- -- -- -- teacher goal achievement (no influence on own task) acts of students (appealing them) appendices top beauty orgaesth teachers respondents of top- orgaest beauty of top- orgaest beauty of top- orgaest beauty of top- orgaest beauty of top- orgaest beauty teacher work attitude of colleagues (reliability) style and support of management attention to new ideas contacts with customers (parents of students) goals / services (possibility of knowledge transfer to students) teacher -- -- -- -- -- teacher internal communication / collegiality coherence of things (alignment) work attitude of colleagues growth (organization development) -- teacher collegiality / internal cooperation (team) collegiality other (special days like easter, christmas) attention to new ideas work attitude of colleagues / collegiality teacher collegiality work attitude of colleagues work atmosphere (social safety in school) work attitude of colleagues (want to improve) nice colleagues top ugly orgaesth teachers respondents of top- ugly orgaest of top- ugly orgaest of top- ugly orgaest of top- ugly orgaest of top- uglyorgaest teacher work attitude of colleagues work load / no control of planning strategy (cuts of finance) contacts with management (distance / accessibility) influence of planning (holidays) teacher -- -- -- -- -- teacher locations (buildings) no staff (administration) work attitude of colleagues teacher interior (gym) internal communication internal communication / work attitude of coll (gossip) work attitude of colleagues internal communication teacher style of management decision of management (continuity of school) work attitude of some colleagues work load / influence on planning high diversity of ability / attitude colleagues to change appendices appendix : data empirical study - surgeons highest scores pae surgeons respondents highest judgment paes highest emotional impact paes highest judgment x emotional impact paes surgeon goal achievement goal achievement goal achievement surgeon goal achievement interaction with colleagues interaction with colleagues receiving recognition interaction with colleagues goal progress surgeon act of customers act of customers receiving recognition act of customers surgeon interaction with colleagues goal achievement interaction with colleagues goal achievement interaction with colleagues surgeon goal achievement goal progress goal achievement goal progress goal achievement goal progress highest scores (mean) paes surgeons respondents gem highest judgment paes gem highest emotional impact paes gem highest judgment x emotional impact paes surgeon receiving recognition interaction with customers interaction with colleagues receiving recognition surgeon involvement with planning stimulus from physical environment receiving recognition stimulus from physical environment stimulus from physical environment surgeon acts of customers goal progress acts of customers goal progress surgeon interaction with colleagues receiving recognition receiving recognition surgeon interaction with customers involvement with planning interaction with customers goal progress interaction with customers highest scores nae surgeons respondents lowest judgment naes highest emotional impact naes highest judgment x emotional impact naes surgeon interaction with colleagues goal achievement interaction with colleagues influence or control goal achievement interaction with colleagues influence or control surgeon goal achievement goal achievement goal achievement interaction with colleagues not functioning ict surgeon goal achievement interaction with colleagues goal achievement appendices interaction with colleagues involvement with planning interaction with colleagues involvement with planning surgeon goal achievement acts of customers influence or control goal achievement acts of customers goal achievement acts of customers surgeon goal achievement interaction with colleagues goal achievement highest scores (mean) naes surgeons respondents gem lowest judgment naes gem highest emotional impact naes gem highest judgment x emotional impact naes surgeon interaction with colleagues interaction with colleagues interaction with colleagues surgeon goal progress acts of customers goal progress surgeon acts of customers influence or control involvement with planning acts of customers acts of customers surgeon acts of customers acts of customers acts of customers surgeon influence or control receiving recognition acts of customers receiving recognition acts of customers top mentioned paes surgeons respondents of top- paes of top- paes of top- paes of top- paes of top- paes surgeon goal achievement (recovery of patient) goal achievement (idem) receiving recognition (from inspection) other (open day hospital, nice atmosphere) acts of colleagues (drinking beer together end of the week) surgeon -- acts of customer (happy patient) receive recognition interaction with colleagues (cooperation in partnership) interaction with colleagues (the secretariat) -- surgeon acts of customer (compliments) receiving recognition acts of colleagues act of management (support of management) goal progress (good operation) interaction of colleagues surgeon acts of colleagues (cooperation) acts of customer (compliments) receiving recognition other (learning colleagues how to improve) acts of colleagues (work atmosphere) goal achievement (during small operations) surgeon goal achievement goal achievement goal achievement acts of colleagues goal achievement appendices goal progress goal progress goal progress interaction with customers (students) acts of management top mentioned naes surgeons respondents of top- naes of top- naes of top- naes of top- naes of top- naes surgeon less influence or control (treatment) low involvement with planning (work attitude colleagues) act of colleagues (work attitude) goal achievement (recurring patient) low involvement with planning (visit of inspection) surgeon act of colleagues (work attitude) low involvement with planning (stagnation after changes) less goal progress influence or control (issues still to be resolved) less goal progress surgeon no goal achievement (patient) no goal progress (patient) bad act of colleagues (work ethic) bad act of management (unconcerned management) bad goal progress (operation) acts of colleagues(bad work attitude) surgeon act of colleagues (work attitude) dying patient less influence or control (on patient recovery) less influence or control (too much administrative work) other (less privacy of patients) old building surgeon act of colleagues dying patient not functioning ict act of colleagues top beauty orgaesth surgeons respondents of top- orgaest beauty of top- orgaest beauty of top- orgaest beauty of top- orgaest beauty of top- orgaest beauty surgeon internal communication ( short lines) attention for quality attention for new ideas (innovation) vision good financial situation surgeon internal cooperation / working together) collegiality (taking care of each other) colleagues (beautiful people) small organization size colleagues (their ‘names and stories’) surgeon interior (new hospital organization size -- -- -- appendices planned) surgeon internal cooperation (working with other disciplines) possibility of goal achievement (being meaningful to patients contribution to society products and services (multi discipline hospital) offered challenges surgeon services / good working organizational (good ic) contacts with management collegiality / internal cooperation organization of ic interior (new hospital planned) top ugly orgaesth surgeons respondents of top- ugly orgaest of top- ugly orgaest of top- ugly orgaest of top- ugly orgaest of top- uglyorgaest surgeon small organization size = ‘small’ image) bad work attitude of colleagues bad work attitude of colleagues (gossip) style of management (bogged down in evaluations) -- surgeon style of management (bureaucratization) style of management (formalizing solutions) business approach (‘fewer people on the bed) qualities of management (no boldness) qualities of management (no guts) surgeon bad functioning management style of management (bad leadership) process of decision making (ponderous organization /management) style of management (unconcerned management) -- surgeon process of decision making (ponderous organization) interior organization size (too big, too complex) organization size (toomany people to get any harmony) surgeon bad internal coopertaion strategy / services (rare supply of services) appendices appendix : data empirical study - paes professionals correlations teachers surgeons profs all correlation paes mark 'beautiful organization' ( - ) mark 'beautiful work' ( - ) mark 'beautiful organization' ( - ) mark 'beautiful work' ( - ) mark 'beautiful organization' ( - ) mark 'beautiful work' ( - ) goal achievement -, , -, -, * -, -, , , , , , , receiving recognition -, , , -, , , , , , , , , interaction with collegues , , -, -, * -, -, , , , , , , involvement with challenging tasks , ** -, , -, , -, , , , , , acts of customers (students and parents) -, , -, -, -, * -, , , , , , , interaction with customers -, , , , , , , , , , , , goal progress -, , -, -, -, , , , , , , , involvement with decision making -, , -, , , , , , influence or control , ** -, , , , -, , , , , , involvement with planning -, , -, , , , , , acts / interaction with management , , , -, , , , , other , ** -, , , , ** , , , , , , stimulus from physical environment , -, -, -, , , , , not-functioning ict appendices appendix : data empirical study - naes professionals correlations teachers surgeons profs all correlation naes mark 'beautiful organization' ( - ) mark 'beautiful work' ( - ) mark 'beautiful organization' ( - ) mark 'beautiful work' ( - ) mark 'beautiful organization' ( - ) mark 'beautiful work' ( - ) goal achievement -, -, -, -, -, -, * , , , , , , receiving recognition -, -, . a . a -, , , , , , interaction with collegues , -, -, -, , -, ** , , , , , , involvement with challenging tasks . a . a acts of customers (students and parents) -, -, , -, , -, , , , , , , interaction with customers , -, . a . a -, -, , , , , goal progress , -, -, -, -, -, * , , , , , , involvement with decision making , -, -, -, -, -, , , , , , , influence or control , -, , -, , -, * , , , , , , involvement with planning , -, -, -, , -, ** , , , , , , acts / interaction with management , -, -, -, -, -, * , , , , , , other -, -, -, -, -, -, , , , , , , stimulus from physical environment - , ** , , , -, , , , , , , not-functioning ict -, -, . a . a -, -, , , , , appendices appendix : data empirical study - associations formal properties formal property associations made by surgeons associations made by teachers preliminary school . harmony quality and transparency x the partnership cooperation operate x cooperation with colleagues same orientation staff . climax doing surgery x the operation successfully completing an operation emergency policlinic ‘golden moments’ after meetings inspiration of colleagues a top day study days pleasure . contrast / variety patients organization of the partnership work schedule x type of work (on service, department, ok, emergence) differences in taking responsibility not to much administrative work the lessons irritation . symmetry aesthetic results scar x building the building balance ongoing concern and development boring . repetition / rhythm x work at the policlinic variety work schedule annual plans every day new chances for learning same things every year securing repetition social safety . unity x the partnership (the firm of doctors) x ok-team teams of assistants similar methods in different groups (classes) together using same learning methods x team the framework . balance / coherence x work – life balance the partnerships work – life balance x workload - resting skewed task distribution . grouping work by specialization professional groups x surgery group x socialibility (with colleagues) at friday afternoon classes - group building groups (isolated) . transparancy x complications results work and patient delegation transparency of school results transparency towards each other x transparency of communication appendices organization structure . focus / dominance quality me patients care focus on the work group of older surgeons moroccan community barkers are recognized and rewarded innovations results motivation . dynamic the care process moving = living having service the surgery specialism emergency policlinic the group of children in the classroom x varied work position in society appendices appendix : overview data professionals and general employees general employees professionals differences overview correlations i h a ve b e a u ti fu l w o rk m a rk ` b e a u ti fu l o rg a n iz a ti o n ' i h a ve b e a u ti fu l w o rk m a rk ` b e a u ti fu l o rg a n iz a ti o n ' n o n -p ro fs - p ro fs w o rk n o n -p ro fs - p ro fs o rg a e st h employee qualities , , - , , , , composition of staff , , - , - , , , employees´ work attitude , , - , , , , attention for craftsmanship , , - - - - employees´ goals , , - - - - collegiality - - - , , - - contacts with customers , , , , , - , feedback of colleagues - - , * , - - qualities of management , , - , , , , style of management , , , , , , decisions of management - - - , , - - support of management - - - , , - - offered challenges , , , , , - , attention for new ideas , , , , * , - , contacts with management - - , , - - balance between organization goals and employees' goals , , , , ** , - , alignment of activities , , , , , , variety of work - - , , - - autonomy , , , , , , internal communication , , , , , , alignment between management and employees , , - , , , , possibility of goal achievement / task completion - - , ** , - - business approach , , - , , , , organization rituals , , - , , , , working towards same goals , , , , , , influence on planning - - - , , - - appreciation from organization - - - , , - - work atmosphere , , , , , , products and services , , , - , , , image , , , - , , , organization mission , , , , , , organization goals , , - , , , , contribution to society , , , , , , appendices general employees professionals differences overview correlations i h a ve b e a u ti fu l w o rk m a rk ` b e a u ti fu l o rg a n iz a ti o n ' i h a ve b e a u ti fu l w o rk m a rk ` b e a u ti fu l o rg a n iz a ti o n ' n o n -p ro fs - p ro fs w o rk n o n -p ro fs - p ro fs o rg a e st h attitude towards society , , , , , , organizational adaptability - - , , - - workplace , , , , - , - , interior , , , ** , - , - , cooperation (internal) , , , , , , personal development opportunities , , , , - , - , house style , , , , - , - , organization size - - - , - , - - team size - - - , - , - - coherence of things , , , , , , appendices appendix : overview questions focus of organizational aesthetics a. strategy-approach b. management-approach c. system-approach critical moments and occasions are product and services, company philosophy, goals / strategy, mission and image perceived as beautiful? are qualities of management, management style, decision making, management support, offered challenges, balance between organization and personal and attention to new ideas perceived as beautiful? are alignment of activities, offered variety of tasks, autonomy, internal communication, alignment management with employees, goal achievement and task completion perceived as beautiful? induce paes representati on represent product and services, company philosophy, goals / strategy, mission and imagethe values of employees and / or customers? represent qualities of management, management style, decision making, management support, offered challenges, balance between organization and personal and attention to new ideas the values of employees? represent alignment of activities, offered variety of tasks, autonomy, internal communication, alignment management with employees, goal achievement and task completion the values of employees? coherence do product and services, company philosophy, goals / strategy, mission and image show coherence with each other? is what aspect show management style coherence? -- accomplish- ment which goals and learning goals have been achieved? is management style supportive to employees and to their learning needs? contribute alignment of activities, offered variety of tasks, autonomy, internal communication, alignment management with employees to accomplishment and learning? collaboration is good internal collaboration considered as a competitive advantage? is management style supportive to internal collaboration? -- avoid naes which product and services, company philosophy, goals / strategy, mission and image are perceived as ugly? which qualities of management, management style, decision making, management support, offered challenges, balance between organization and personal and attention to new ideas are perceived as ugly ? which alignment of activities, offered variety of tasks, autonomy, internal communication, alignment management with employees, goal achievement and task completion are perceived as ugly? incorporate in organization is aesthetic appreciation a requirement for is aesthetic appreciation a requirement for applying qualities of management, is aesthetic appreciation a requirement for applying alignment of activities, offered appendices a. strategy-approach b. management-approach c. system-approach routines defining product and services, company philosophy, goals / strategy, mission and image? management style, decision making, management support, offered challenges, balance between organization and personal and attention to new ideas? variety of tasks, autonomy, internal communication, alignment management with employees, goal achievement and task completion? guard mystery how are product and services, company philosophy, goals / strategy, mission and image kept exciting? how are qualities of management, management style, decision making, management support, offered challenges, balance between organization and personal and attention to new ideas kept exciting? how are alignment of activities, offered variety of tasks, autonomy, internal communication, alignment management with employees, goal achievement and task completion kept exciting? d. staff-approach e. culture-approach f. structure-approach critical moments and occasions are employees work attitude qualities, collegiality, contacts with customers, development opportunities and internal cooperation perceived as beautiful? are organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence and employee recognition and appreciation perceived as beautiful? are interior / exterior, house style / internal communication perceived as beautiful? avoid naes which employees work attitude qualities, collegiality, contacts with customers, development opportunities and internal cooperation are perceived as ugly? which organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence and employee recognition and appreciation are perceived as ugly? which interior / exterior, house style / internal communication perceived as ugly? induce paes representati on represent employees work attitude qualities, collegiality, contacts with customers, development opportunities and internal cooperation the values of employees? represent organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence and employee recognition and appreciation the values of employees? represent interior / exterior, house style / internal communication the values of employees? coherence -- -- -- accomplish- ment contribute employees work attitude and qualities, collegiality, contacts with customers, contribute organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence -- appendices d. staff-approach e. culture-approach f. structure-approach development opportunities and internal cooperation to accomplishment? andemployee recognition and appreciation to accomplishment? collaboration contribute employees work attitude and their qualities to internal collaboration? contribute organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence andemployee recognition and appreciation to internal collaboration? contributesinterior of the organization to internal collaboration? complexity do employees demand challenges and task variety? contribute organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence andemployee recognition and appreciation tooffered challenges and task variety? -- incorporate in organization routines is aesthetic appreciation a requirement for work attitude qualities, collegiality, contacts with customers, development opportunities and internal cooperation? is aesthetic appreciation a requirement for organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence and employee recognition and appreciation? is aesthetic appreciation a requirement for interior / exterior, house style / internal communication? guard mystery how are attitude qualities, collegiality, contacts with customers, development opportunities and internal cooperation kept exciting? how are organization philosophy, organization rituals, working on the same goals, involvement / solidarity, employee influence and employee recognition and appreciation kept exciting? how are interior / exterior, house style / internal communication kept exciting? appendices appendix : invitation validation workshops beste relatie, ik ben ruim drie jaar bezig met mijn promotie-onderzoek naar schoonheidsbeleving in werk en organisaties aan de tu eindhoven onder leiding van prof. mathieu weggeman. de belangrijkste resultaten van dit onderzoek zijn ) een (geprioriteerde) lijst van ‘schoonheidsdragers’ zoals samenwerking, de samenhang der dingen in de organisatie en waarden van management en collega’s, ) de conclusie dat de principes voor schoonheidsbeleving in organisaties overeen komen met die voor beschouwing van de kunsten en dat mooi bijdraagt aan goed. in mooie organisaties is sprake van een hoge mate van werkplezier, trots, eigenaarschap en binding wat volgens onderzoek direct bijdraagt aan prestaties. ik bevind me nu in de fase van design en zou graag in drie organisaties een aantal ontwerpprincipes willen toetsen. ik zou dat graag doen in maart gedurende een gratis workshop van uur met ongeveer - medewerkers. mijn vraag is daarom of uw organisatie mee zou willen werken, door medewerking te verlenen aan deze gratis workshop die ik zelf zal uitvoeren. de opbrengst voor uw organisatie is inzicht in welke aspecten medewerkers als mooi en lelijk ervaren en naar welke interventies hun voorkeur uitgaat. ik zou enorm geholpen als enkel medewerkers van uw organisaties gehoor willen geven dit initiatief! uiteraard bespreken we vooraf de opzet en dergelijke. ik kijk uit naar uw reactie. mocht uw vragen hebben over dit verzoek, dan kunt u mij uiteraard benaderen. vriendelijke groet steven de groot bijlage appendices bijlage op april a.s. geef ik de workshop ‘schoonheid in organisaties’ in het kader van mijn promotie- onderzoek. fijn dat je hierbij aanwezig bent! om de tijd tijdens de workshop goed te besteden helpt het me als ik vooraf al wat antwoorden van je heb. wil je de onderstaande vragen beantwoorden en deze fysiek of elektronisch voor april a.s. aan me sturen (steven.de.groot@vtspn.nl)? . kijk eens terug op je vorige werkweek. welke aspecten in je werk en/of organisatie ervaar je als mooi? a. b. c. . kijk eens terug op je vorige werkweek. welke aspecten in je werk en/of organisatie ervaar je als lelijk? a. b. c. . waardeer met een cijfer ( - ; is zeer mooi) de schoonheid van de volgende schoonheidsdragers schoonheidsdrager oordeel in cijfer - . cultuur in de organisatie . kwaliteiten van management . samenhang der dingen in de organisatie . de houding tegenover onze omgeving . de afstemming tussen management en medewerkers . interne samenwerking . organisatie-filosofie (zo werken we hier’) . managementstijl . balans tussen organisatiedoelen en individuele doelen . onderlinge afstemming van activiteiten in onze organisatie . werken aan dezelfde doelen . organisatie rituelen (zoals borrels, attentie bij ziekten / vreugde, etc.) . aangeboden uitdagingen in werk . interne communicatie . producten and diensten . leer- en ontwikkelmogelijkheden mailto:steven.de.groot@vtspn.nl appendices tijdens de workshop ‘schoonheid in organisaties’: . welke ontwerpprincipes zijn volgens jou momenteel het meest geschikt voor je organisatie? a. b. . welke activiteiten adviseer je om morgen mee te starten om te komen tot een mooie(re) organisatie? a. b. c. . reflecteer op het idee van schoonheid in organisaties. noem redenen waarom je organisatie wel / niet aan de slag zou gaan met dit onderwerp. . reflecteer op de workshop. wat is voor jouw persoonlijk het effect geweest van deze workshop? noem maximaal effecten. a. b. het ingevulde formulier graag achterlaten bij steven dank voor je bijdrage! appendices appendix : description validation workshops target group: - dutch professional organizations - staff and management ( - employees) goals: . enhancing employees’ aesthetic consciousness and their attention to aesthetics (priming and starting reframing) . achieving same language and a collective ambition about organizational aesthetics . selecting interventions the organization probably will apply after the workshop secondary goals, in particular for the researcher: . testing the recognizability and usability of the list of interventions . collecting ideas about functional requirements . collecting indications and contra-indications duration: - hours agenda: min. min. min. min. min. min. min. min. min. steps . start (introduction manager), agenda and goals . introduction organizational aesthetics . reflection on collected answers: beauty and ugliness in work and organizations and appreciation of oas . difference between good and beauty . from oas to design principles . starting with organizational aesthetics? . collecting en selecting ideas for interventions . collecting ideas about requirements, indications and contra-indications . conclusions methods and supplies presentation (sheets) presentation (sheets) answers quick scan presentation (sheets) presentation (sheets) discussion discussion and presentation (sheets) discussion and presentation (sheets) -- appendices appendix : data validation workshops overview of participants of the workshops organization participants vtspn m/v: employees (information management consultants, performing same work) , manager waterschap aa en maas m/v: employees, managers ccl m/v: employees (psychologists, performing same work), manager waterschap valei en veluwe m/v: employees min szw m/v: employees reactions after asking participants before to workshop to register things they experienced as beautiful and thing s they experience as ulgy in their work and organization and to value the most strongly oas found during earlier conducted field research. organization statements vtspn ‘the questions triggered me’ ‘the issue effects both sides: myself and my organization’ ‘ugliness can also be not dysfunctional’ ‘the questions forced me to define what gives me satfifaction in my work’ ‘beautiful things can be destroyed’ “beauty can positively effect good’ waterschap aa en maas -- ccl ‘the questions were never asked me before’ ‘they forced me to think why i really go to work’ waterschap valei en veluwe ‘beautiful things are much easier to define than ugly things’ ‘it was easy to choose things for both categories, and hard to mention a third’ inspectie szw -- appendices . choice of design principles design principles vtspn aa en maas ccl valei en veluwe insp szw t o ta ls . enhance aesthetic awareness (priming and reframing) . utilize critical moments for attention to aesthetics . apply collaborative change / design methods . avoid naes: remove barriers for goal progress . induce paes: a. reinforce coherence by formal properties) b. stimulate interaction c. condition accomplishment (goal progress and achievement and task completion) d. enhance representation (value and goal congruence) . incorporate the attention to aesthetics in organization routines . guard mystery: a) avoid habituation to beauty and ugliness b) offer new chances for aesthetic experiences -- . increase the chance of a good p-o fit for new employees (based on aesthetic commitment) . other - remove obstacles that are unneccessary (vgl. ) appendices . choice of interventions interventions vtspn aa en maas ccl valei en veluwe insp szw a. measure organization’s aesthetic consciousness (dp ): - visit other organizations for reflection on own organization - conduct an employee satisfaction survey - improve consciousness of quality of work - collect and exploit ‘nice moments’ / paes - discussing ‘ paes at the end of the day - celebrate beauty - apply positive reflection - share paes with each other - exploit new employees (fresh look) to collect paes - focus on positive characteristics of employees dp dp a/ b dp / dp / ac/ dp / / dp b/ c / dp / / dp / / dp / dp / ac/ (dp / )/ dp / dp / dp / b dp / b / dp / c dp / dp / c dp / b dp / b b. in a workshop(s), reflect on ‘the current awareness and state of beauty’ (dp ); - determine what to make more beautiful - offer trainingen (szw academy) org. aesthetic - workshop for mt dp / * dp / a dp / dp / dp / c. use a simplified edition of the bel-book (dp ) dp / ac dp / d. exploit exisiting performance improvement appendices interventions vtspn aa en maas ccl valei en veluwe insp szw / quality teams (dp ) e. design and implement bottom-up (with teams, departments and bu’s) (dp ): - apply collaborative change / design methods (design principle ) - apply collaborative change / design methods dp a/ b dp a/ b/ c f. stimulate ideas and initiatives against ugliness and for beauty by a ‘pandora’s box’ (by analogy with ideas-box) (dp ) dp / g. collect (causes for) naes (dp ): - remove barriers for goal progress (design principle ) dp a/ b dp / b dp / c / dp / h. elaborate and align employees’ values and goals with organization values and goals (shared values) (dp d): - describe / let employees tell who is doing what and where - hang a board with our values on it - define (shared) values - improve possibilities for identification with the organization - introduce ‘added value’ dp a dp / b dp / a dp / dp b/ dp / dp / ac dp a/b / dp / / dp / i. stimulate and improve interaction between colleagues and between staff and management (dp b): - stimulate interaction based on coherence of things of sequence of things - better listening and show respect - ask more often help from colleagues / improve interaction - improve identification management with ‘floor’ - stimulate (better) interaction between employees - create meeting places in the organization - work together beyond the boundaries of bu’s dp / b dp / c dp / c dp a/ b dp a/ b dp / dp / dp b/ dp dp a/b dp / j. associate and value most common aesthetic formal properties k. make coherence transparent and value links and interdepencies (dp a): dp / dp / b dp / dp / dp / appendices interventions vtspn aa en maas ccl valei en veluwe insp szw - define current activities as starting point for standardization of processes - make transparent who can contribute to individual quality of work - reinforce coherence by formal properties) - define who is expert in what dp / a dp / dp a/ b/ c dp / b l. coordinate coherence (dp a): - relationship strategy – planning and control dp / dp / m. define a collective ambition (dp c): - define clear goals dp / a dp / b dp / c dp / n. elaborate and agree conditions for realizing agreed tasks / goals (dp c): - condition accomplishment (goal progress and achievement and task completion) (design principle c) - show effects of internal cooperation - improve autonomy of employees - improve space for creativity of employees / retaining curiousity dp a/ b dp a/ b dp / dp / dp / b dp / o. add the role of beauty in the pdca-cycle (plan-do-check-act) (dp ): - incorporate the attention to aesthetics in organization routines dp a/ b/ c p. add ‘beauty’ as a requirement for quality and performance (dp ) dp / b dp / dp / q. add ‘contribution to organizational aesthetics’ to the hr-cycle (dp ) r. guard mystery (dp ) dp / dp / s. describe organizational indentifiability during a job interview (dp ) new t. shift responsibility for results to employees dp / a dp a/ b u. reduce bureaucracy (dp ) dp / c v. improve communication about reorganization better sharing information dp / c dp / a dp / w. based on design principle c: split projects in smaller periods (dp c) dp c x. design (artistic) workplaces dp / dp / appendices interventions vtspn aa en maas ccl valei en veluwe insp szw design workplaces in telation to type of work dp / y. start ‘own’ ict team as part of projects to improve cooperation dp / c z. start ‘own’ ict team as part of police processes to improve cooperation with business dp / c aa. based on design principle : test match with organization psychology dp bb. provide job security (in relation to reorganization) dp / a cc. celebrate successes dp / c dp / dp / b dp / dd. roulation of work dp / ee. time-out (really out of work) dp ff. inform new employees better dp / gg. limit the number of projects dp / hh. improve employee commitment (more autonomy, commitment, craftsmenship) (dp c/d) dp / ii. improve openness and alignment on strategy dp b/ jj. focus on learning organization dp d/ b kk. from tie to jacket (everyone same style) dp d/ b ll. enhance competence management -- * = number of mentioned intervention (earlier mentioned design principle by the respondent to have attention to in his/her organization) appendices relationship design principles and interventions interventions/ design principles a b c d a b a. measure organization’s aesthetic consciousness (dp ) r b. in a workshop(s), reflect on ‘the current awareness and state of beauty’ (dp ) r c. use a simplified edition of the bel-book (dp ) r d. exploit exisiting performance improvement / quality teams (dp ) r e. design and implement bottom-up (with teams, departments and bu’s) (dp ) r f. stimulate ideas and initiatives against ugliness and for beauty by a ‘pandora’s box’ (by analogy with ideas-box) (dp ) r g. collect (causes for) naes (dp ): r h. elaborate and align employees’ values and goals with organization values and goals (shared values) (dp d) r i. stimulate and improve interaction between colleagues and between staff and management (dp b) r j. associate and value most common aesthetic formal properties r k. make coherence transparent and value links and interdepencies (dp a) r l. coordinate coherence (dp a): r m. define a collective ambition (dp c): r n. elaborate and agree conditions for realizing agreed tasks / goals (dp c) r o. add the role of beauty in the pdca-cycle (plan-do-check-act) (dp ) r p. add ‘beauty’ as a requirement for quality and performance (dp ) r q. add ‘contribution to organizational aesthetics’ to the hr-cycle (dp ) r r. guard mystery (dp ) r r s. describe organizational indentifiability during a job interview (dp ) r new appendices interventions/ design principles a b c d a b t. shift responsibility for results to employees u. reduce bureaucracy (dp ) v. improve communication about reorganization better sharing information w. based on design principle c: split projects in smaller periods (dp c) x. design (artistic) workplaces design workplaces in telation to type of work y. start ‘own’ ict team as part of projects to improve cooperation z. start ‘own’ ict team as part of police processes to improve cooperation with business aa. based on design principle : test match with organization psychology bb. provide job security (in relation to reorganization) cc. celebrate successes dd. roulation of work ee. time-out (really out of work) ff. inform new employees better gg. limit the number of projects hh. improve employee commitment (more autonomy, commitment, craftsmenship) (dp c/d) ii. improve openness and alignment on strategy jj. focus on learning organization kk. from tie to jacket (everyone same style) ll. enhance competence management appendices . arguments for starting / not starting with theorganizational aesthetic perspective arguments for yes / no vtspn aa en maas ccl valei en veluwe insp szw t o ta ls arguments for yes a. attention to aesthetics positively effects work experience (‘welfare before prosperity’), quality, productivity and/or organization improvement beauty can contribute to good b. this makes me happy (more work pleasure), which makes me perform better c. the perspective is causing more motivated employees d. the perspective will effect a better serviced customer e. better understanding of in where to embed beauty f. the perspective strengthens the belief in the future of the business unit new way working can be realized along this perspective g. a reason to achieve more transparency / harmony / balance in the organization h. understanding the work perception of colleagues i. adopting this perspective contributes to a better image of the business unit and to cooperation with other units in the organization j. it supports the essence of our services (helping young people) k. it validates out work approach l. it enhances the awaress for beauty in our organization m. our organization is receptive to this perspective n. employees’ improved aesthetic awareness contributes to customer satisfaction o. speaking in terms of aesthetics simplifies language (´care language’) p. fits with our attention to subjectivity q. enhances the attention to keep our organization beautiful r. possibility to connect beauty to revenues s. this perspective avoids to think negatively t. perspective guards our identity u. it can be even more beautiful v. awareness for beauty could form a stable base in case of organization change appendices arguments for no vtspn aa en maas ccl valei en veluwe insp szw t o ta ls w. not by using the terms aesthetics or beauty, it is a container concept, hard to define x. first the work and results need to be defined y. no attention to aesthetics in case of future reorganization z. other priorities aa. we are focusing on efficiency bb. our organization is too conservative / wants to have everything in control cc. we already implicitely work on beauty dd. low priority in times of cuts . effects on participants of the workshop perceived effects of workshop vtspn aa en maas ccl valei en veluwe insp szw t o ta ls good feeling . nice to talk about work / organization in this way . nice to discuss this subject with colleagues . positive feeling . inspiration changed attitude . awareness . awareness of the importance of coherence of things . we should really have more attention to ugly things in our organization . thinking different / more nuanced about good and its difference with beauty . being consciousness to keep what we have . changed my attention from bad things to beautiful things . becoming more enthusiastic about my organization . reflection on own daily work new knowledge / insight . understanding that the perspective increases the resistance to entrenched ways of thinking . trigger for thinking differently, new opportunities . extra attention for focussing on internal cooperation . food for thought . understanding of the work perception of colleagues . understanding that beauty can contribute to good appendices perceived effects of workshop vtspn aa en maas ccl valei en veluwe insp szw t o ta ls . possibility to validate our organization approach . new grasping point for discussion with colleagues . by registering aspects which are perceived as beautiful and ugly, the concept become more clear . understanding that ‘beauty’ doesn’t need an explanation (it is beautiful because you perceive it is) and does not cause a discussion about what is good . understanding that organizational aesthetics could be a new design principle and how to apply these . understanding about more to focus on nice things in my work . even in times of economic crisis, many things seems to be beautiful activation . activation: - beauty is my own responsibility - we really should start with this perspective . recommend workshop to colleagues appendices appendix : vocabulary organizational aesthetics aesthetic commitment aesthetic commitment is the degree of employees feel attached to an organization based on organization’s aesthetic properties and aesthetic value and the work the organization facilitates. aesthetic properties or qualities features of organizational aesthetic stimuli (oas) which cause aesthetic experiences, such as aesthetic formal properties (balance, harmony, peak-shift, unity, etc.), aesthetic representational properties (values, goals, etc.) and aesthetic expressive properties (color, sound, etc.). aesthetic judgment perceiver´s judgment of the aesthetic value of organizational aesthetic stimuli (oas) a result of the evaluation of the cognitive mastering stage (expressed in a degree of beauty - ugliness) and an emotion (an emotional reaction which is a by-product of the processing stages of the aesthetic process). aesthetic value value of organizational aesthetic stimuli (oas) perceived by an observer that causes an aesthetic experience because of recognition or attribution of (a degree of) aesthetic properties or qualities in these stimuli. affect grid grid (based on russell, weiss and mendelsohn), formed by an x-ax and y-ax, in which respondents position their aesthetic judgment (degree of beauty - ugliness) and their (degree of) emotional impact of an aesthetic experience. affective commitment affective commitment, as part of employee commitment, is a feeling of attachment and belonging to an organization, that includes the structure of the organization, the type of work experiences, and personal characteristics. it is categorized by a strong belief and acceptance of the goals and values of the organization, a willingness to put extra effort on behalf of the organizations and a desire to remain e a member of the organization. affective events theory the affective events theory (aet), developed by weiss and cropanzano ( ), aspires that affect driven behaviors will be predicted by affective reactions and not by cognitive evaluation or overall job satisfaction. the aet framework is build by the boxes (and connections in between) events, influenced by work environment features and dispositions (personal characteristics), which cause affective reactions which cause the ‘anticipated outcomes’ judgment driven behaviors, work attitude (job satisfaction) and affective driven behaviors. beautiful organization organization which is valued as beautiful by their employees’ experience, because of having much positive aesthetic experiences (paes) and less negative aesthetic experiences (naes) because of the degree of presence and attribution of aesthetic properties such as coherence and representation in organizational aesthetic stimuli (oas). appendices bel book the beauty experience log book (bel book) is a self-report and method for collecting and valuing daily aesthetic (positive and negative) experiences. cimo a cimo is as a technological rule applied in design science research which argues that the logic of prescription is ‘if you want to achieve outcome o in context c, then use intervention type i’. in relation to organizational aesthetics, cimo-configurations show constructions of a context (c) in which aesthetic properties in organizational aesthetic stimuli (oas) are revealed and exploited (i), in which it is likely that aesthetic experiences will take place (m) and will contribute to affective commitment of employees (o). design principle a design principle emphasizes the importance of a certain type of solution in view of certain values or goals (e.g. ´to achieve a, do b´). design principles outline the deeper meanings and intentions behind design interventions. in relation to organizational aesthetics, the major design principles are: add aesthetic value to organization design, accept that aesthetic value (beauty) is in the eye of the beholder (object-subject construction); predicate organization design based upon motivational needs, rearrange form and properties (of organization design) as a consequence of changing needs and values of employees, designate and exploit organizational aesthetic stimuli (oas) to effect aesthetic experiences (paes / naes) and aesthetic properties (formal, representational and expressive properties in oas) supervene on non-aesthetic properties (components of esh-model). design causality the relationship between form, properties, function, needs and values in design propositions. design (form) is made by people for its properties. because of these properties it can fulfill one or more functions. by fulfilling functions a design satisfies needs, and give people the possibility to satisfy one or more values. following these fundamentals, the design of the organization needs to change as a consequence of changing roles and needs of the employees. design principles or rules design principles or rules are solution-oriented guidelines for the design process (e.g. ‘if condition c is present, to achieve a, do b’). in relation to organizational aesthetics, the major design principles are: enhance aesthetic awareness and sensitivity (priming and reframing), utilize critical moments and occasions for attention to aesthetics, apply collaborative change methods or design methods, avoid naes, induce paes, incorporate the attention to aesthetics in organization routines, guard mystery. nae a negative aesthetic experience (nae) is an aesthetic experience that causes a negative aesthetic judgment to the observer. oas see organizational aesthetic stimuli. organizational aesthetic experiences experiences (paes and naes) caused by organizational aesthetic stimuli (oas). appendices organizational aesthetic process by an observer experienced internal process of observing organizational stimuli of perceptual analysis (complexity, contrast, symmetry, order, grouping), implicit memory integration (familiarity, prototypically, peak-shifts), explicit classification (style and content), cognitive mastering context- specific-interpretation and self-related-interpretation), and evaluation (understanding, ambiguity and satisfaction). organizational aesthetic properties organizational aesthetic properties are qualities or characteristics of organizational aesthetic stimuli (oas) which are the originators of aesthetic experiences. particular to organizations, coherence, complexity, accomplishment, representation, collaboration and mystery are most influential aesthetic properties that cause aesthetic experiences at employees. organizational aesthetic stimuli organizational aesthetic stimuli (oas) are those stimuli or cues that cause aesthetic experiences because of the degree of presence or attribution of aesthetic properties in these oas. examples of oas are coherence of things, collegiality, work attitude of employees and personal development opportunities. organizational aesthetic value perceived value based on aesthetic experiences. pae a positive aesthetic experience (pae) is an aesthetic experiences that causes a positive aesthetic judgment to the observer. summary summary developing beautiful organizations a design study to design principles for combining aesthetics with functional value in organizations. many current dutch organizations are designed and controlled primarily from a functional perspective, partly due to the influence of scientific management paradigm which was introduced at the end of the th century. functionally in a way that organizations should strongly focus on financial returns and particularly on effectiveness and efficiency. in disciplines such as product design and architecture design principles as 'user-centered' and 'form follows meaning' are translated into a distinction between functional value and aesthetic value. while people have aesthetic experiences in daily life and fulfill their needs for these, in their working life they seem to have less attention to aesthetic value. to analogy of 'doing good things in a good way ' (efficiency x effectiveness), could be ´doing beautiful things in a beautiful way´ (beauty production x production beauty) a fruitful idea? do employees experience alongside functional value in their work and organization also aesthetic value? and if so, in which stimuli and because of which properties do they experience aesthetic value? and if so, which design principles can be applied to develop beautiful organizations? this research started from the research question: what design principles (design protocol) can be used to develop, design and sustain an organizational design for professional organizations which decrease negative aesthetic experiences and increases positive aesthetic experiences of professionals? this design research thus focuses on the aesthetic value for employees in their work and organizations and on the possibility (design principles) to increase this value. the scarce literature on this relatively new subject discusses whether an aesthetic perspective on organizations could be a fruitful perspective and suggests some and initial aspects in which employees could experience aesthetic value in their organization. these first contributions on 'organizational aesthetics' are characterized by a high deductive nature. there is little empirical research in organizations to aesthetic experiences of employees. furthermore, the few contributions in the literature are hardly embedded in existing organizational theories, in other design disciplines and in theories of aesthetics. the described three main ingredients of an aesthetic perspective on organizations are therefore ( ) aesthetics and design disciplines in which the role aesthetics is indisputable, ( ) organizational design and ( ) emotions in organizations and in particular the contributions to affective commitment of employees. affective commitment concerns the involvement of employees based on affection or positive emotions. through an extensive literature review and empirical research (mixed methods (qualitative and quantitative): interviews, self reports and survey), consisting of five empirical studies ( respondents from organizations), a diagnostic analysis of the problem described above has been performed. the literature review has resulted in a design logic (based on roozenburg & eekels, ) in which the adoption of aesthetic value, based on employee needs to aesthetic experiences, affects the function, properties and form (design) of the organization. which in practice cause a good chance that employees (subject) will have positive aesthetic experiences within their organization (object), which leads to the feeling of 'i work in a beautiful organization' which ultimately contributes to their affective commitment. the latter reasoning refers to the applied affective events theory of weiss and cropanzano ( ). summary these studies show that employees are having daily positive and negative aesthetic experiences (paes: positive aesthetic experiences; naes negative aesthetic experiences) experienced in more or less the same stimuli (oas: organizational aesthetic stimuli), regardless of the variety of organizations in which they work. negative aesthetic experiences are mostly due to the dysfunction aspects in the organization. the aesthetic properties of the stimuli that cause paes are categorized along four specific properties of 'beautiful organizations´: ( ) the coherence of things (coherence), ( ) recognition (especially values and goals), ( ) goal and task achievement (accomplishment), and ( ) collaboration. the study also proved that employees get used to stimuli that cause daily aesthetic experiences to them. their aesthetic appreciation decreases over time. therefore another property of beautiful organizations is added, which is ( ) mystery. attention to mystery must prevent employees (subject) to the habituation of stimuli that offer them daily aesthetic experiences. and it also challenges the organization (object) to offer employees constantly new discoveries and new aesthetic experiences. a striking conclusion is that these properties, besides collaboration, are very similar to the properties of stimuli in the arts creating aesthetic experiences to viewers, such as painting or architecture. the study also shows that these six clusters are embed in all types of organizations. this means that all kind of organizations have the ability and potential to apply and to exploit organizational aesthetics (and thus aesthetic value). further has been proved that aesthetic value in organizations can be functional as well and so, in other words, can strengthen the functional value organization. functional beauty supports thus two purposes: ( ) realizing positive aesthetic experiences of employees (beauty because of beauty) which leads to a (perceived) increase of pride, job satisfaction, ownership and a decrease in absenteeism, which together result in ( ) an increase of affective commitment and thus performance (good because of beauty). this research resulted in design principles for organizational aesthetics and thus focuses on the practical applicability. therefore, this aesthetic perspective on organizations is not only research based designed, based on a new organizational aesthetics framework, but also provides a practical solutions to the questions above. the chosen research strategy is 'design science research' (dsr). this strategy integrates the regulative cycle and the reflective cycle, and aims to generate valid, reliable and transferable knowledge (in the knowledge stream) to solve a field problem (in the practice stream). design science research uses the so-called cimo-logic: an intervention (i) deployed to solve problems in the context (c), will trigger a generative mechanism (m) that leads to outcome (o). for applying organizational aesthetics, organizations that do not exploit the opportunities of organizational aesthetics (c) in which organizational aesthetic properties are adjusted (object-oriented interventions) and /or employee’s awareness and perceptions of organizational aesthetic properties are influenced (subject-oriented interventions) (i) cause increased attention to (organizational) aesthetics (m) which will increase aesthetic value to / and affective commitment of the employee (o). because of the emphasis on solving field problems in design science research, the design principles for organizational aesthetics have been tested during an α-test (workshops with participants on behalf of five organizations). this concerned only two interventions of eight proposed design principles, because only the effect of one of the design principles (to enhance the aesthetic consciousness) could be realized and measured on a short term. summary those eight design principles for organizational aesthetics are detailed in nineteen practical object and / or subject-oriented interventions, providing organizations practical suggestions they could start with tomorrow, from the phase of awareness to securing aesthetic value. this set of design interventions also provides a new and broader repertoire of opportunities for organization improvement and performance improvement. summary dutch summary dutch summary developing beautiful organizations een ontwerpstudie naar ontwerpprincipes voor het combineren van esthetische waarde met functionele waarde in organisaties. veel huidige nederlandse organisaties zijn vooral vanuit een functioneel perspectief ingericht en bestuurd, mede door de dominantie van denken in termen van scientific management dat aan het eind van de e eeuw zijn opmars maakte. functioneel in die zin, dat organisaties vooral effectief en efficiënt dienen te zijn en met een sterke focus op financieel rendement. in ontwerpdisciplines zoals productontwerp en architectuur hebben ontwerpprincipes als ‘user- centered’ en ‘form follows meaning’ zich vertaald naar een onderscheid tussen functionele waarde en esthetische waarde. terwijl mensen dagelijks esthetische ervaringen hebben en hun behoeften hier aan vervullen, lijkt de aandacht hiervoor in hun werkende leven minimaal. bestaat naar analogie van ´op een goede wijze goede dingen doen´ (efficiency x effectiviteit) in organisaties zoiets als ‘op een mooie wijze mooie dingen doen’ (productieschoonheid x schoonheidsproductie)? ervaren medewerkers naast functionele waarde in hun werk en organisatie tevens esthetische waarde, doordat zij esthetische ervaringen hebben tijdens hun werk? en zoja, in welke stimuli en door welke eigenschappen van deze stimuli ervaren zij esthetische waarde? en zoja, met behulp van welke ontwerp- en veranderprincipes zijn organisaties mooier te maken? dit ontwerponderzoek richt zich dus op de esthetische waarde voor medewerkers in hun werk en organisaties en op de mogelijkheid (ontwerpprincipes) deze waarde te doen toenemen. de schaarse literatuur over dit relatief nieuwe onderwerp stelt zichzelf met name de vraag of een esthetisch perspectief op organisaties iets zou kunnen zijn, en doet eerste suggesties voor aspecten waarin medewerkers esthetische waarde zouden kunnen ervaren in hun organisatie. deze eerste bijdragen over ´organizational aesthetics´ kenmerken zich door een hoog deductief karakter. er is nauwelijks empirisch onderzoek gedaan in organisaties naar esthetische ervaringen van medewerkers. verder kenmerken de enkele bijdragen in de literatuur zich door een slechts magere inbedding in bestaande organisatietheorieën, in andere ontwerpdisciplines en in theorieën over de esthetica. de beschreven drie hoofdingrediënten van een esthetisch perspectief op organisaties zijn daarom ( ) esthetica en ontwerpdisciplines waarin de esthetica een belangrijke rol speelt, ( ) organisatieontwerp en ( ) emoties in organisaties en in het bijzonder de bijdragen aan affective commitment van medewerkers. affective commitment betreft de betrokkenheid van medewerkers bij de organisatie op basis van genegenheid of positieve emoties. dit onderzoek resulteert in ontwerpprincipes voor organizational aesthetics en richt zich daarmee op de praktische toepasbaarheid. hierdoor is een esthetisch perspectief op organisaties niet alleen een op wetenschappelijk verantwoorde wijze ontworpen, op basis van een eerste organizational aesthetics framework, maar biedt tevens een bruikbare oplossing voor het hierboven beschreven vragen. het onderzoek start vanuit de onderzoeksvraag: ‘definieer ontwerpprincipes voor nederlandse organisaties waarmee de esthetische waarde voor medewerkers toeneemt en daarmee de bijdrage aan hun affective commitment’. de gekozen onderzoeksstrategie is ‘design science research’ (dsr). deze strategie integreert de regulatieve cyclus en de reflecterende cyclus, en heeft als doel valide, betrouwbaar en transfereerbare kennis te genereren (in de kennisstroom) om een veldprobleem op te lossen (in de praktijkstroom). design science research hanteert de zogenaamde cimo-logica: wanneer je bij problemen in de context (c) een interventie (i) gebruikt, zal dat het generatieve mechanisme (m) triggeren die leiden tot outcome (o). dutch summary vanwege de nadruk op het oplossen van veldproblemen in de design science research, zijn de ontwerpprincipes voor organizational aesthetics getoetst tijdens een α-test (workshops met deelnemers namens organisaties). het betrof hier een test van twee interventies van slechts één van de acht voorgestelde ontwerpprincipes, omdat enkel het effect van dit principe (het vergroten van het esthetische bewustzijn) op een korte termijn realiseerbaar en meetbaar is. door middel van zowel een uitgebreid literatuuronderzoek als een empirisch onderzoek (mixed methods (kwalitatief en kwantitatief): interviews, self reports en survey), bestaande uit vijf deelstudies ( respondenten uit organisaties) is een diagnostische analyse van het hierboven beschreven probleem uitgevoerd. het literatuuronderzoek heeft geresulteerd in een design logica (gebaseerd op rozenburg & eekels, ) waarin de adoptie van esthetische waarde, op basis van behoeften van medewerkers aan esthetische ervaringen, gevolgen heeft voor de functie, de eigenschappen en de vorm van de organisatie. waarbij in de praktijk de kans groot is dat medewerkers (subject) positieve esthetische ervaringen hebben binnen deze aangepaste organisatievorm (object), wat leidt tot het gevoel van ‘ik werk in een mooie organisatie’ wat uiteindelijk bijdraagt aan hun affective commitment. deze laatste redenering verwijst naar de toegepaste affective events theory van weiss en cropanzano ( ). deze studies tonen aan dat medewerkers dagelijkse positieve en negatieve esthetische ervaringen (paes: positive aesthetic experiences; naes negative aesthetic experiences) hebben door min of meer dezelfde stimuli (oas: organizational aesthetic stimuli), ongeacht de verscheidenheid van organisaties waarin zij werken. negatieve esthetische ervaringen komen veelal voort uit het disfunctioneren van zaken in de organisatie, waarmee ´lelijk´ veelal geassocieerd wordt met ´niet goed´ of disfunctioneel. de eigenschappen van de gevonden stimuli zijn terug te voeren naar vier specifieke eigenschappen van ‘mooie organisaties’: ( ) de samenhang der dingen (coherence), ( ) herkenning (identificatie met waarden en doelen), ( ) doel- en taakrealisatie (accomplishment) en ( )samenwerking (interne). omdat tevens is aangetoond dat medewerkers wennen aan stimuli die dagelijkse esthetische ervaringen bij hen veroorzaken, waardoor hun esthetische waardering hiervoor afneemt in de tijd, is een vijfde eigenschap van ‘mooie organisaties’ toegevoegd: ( ) mystery. aandacht voor mystery dient te voorkomen dat medewerkers (subject) op de lange termijn wennen aan de stimuli die hen dagelijkse esthetische ervaringen bieden. en het daagt de organisatie (object) uit medewerkers nieuwe ontdekkingen aan te reiken zodat zij voortdurend nieuwe esthetische ervaringen ondergaan. een opvallende conclusie is dat deze vijf eigenschappen, op samenwerking na, sterk overeenkomen met de eigenschappen van stimuli in de kunsten, zoals de schilderkunst of architectuur, die leiden tot esthetische ervaringen bij beschouwers. ook tonen deze zes clusters aan dat alle typen organisaties de potentie hebben om organizational aesthetics (en dus esthetische waarde) in te bedden en te benutten. verder is aangetoond dat esthetische waarde in organisaties functioneel kan zijn en dus, in andere woorden, de functionele waarde kan versterken. functionele schoonheid dient daarmee twee doelen: ( ) bewerkstellingen van positieve esthetische ervaringen van medewerkers (mooi om mooi) wat leidt tot een (gepercipieerde) toename van trots, werkplezier, eigenaarschap en tot een afname van ziekteverzuim, wat tezamen resulteert in ( ) een toename van affective commitment en daarmee prestatieverbetering (goed door mooi). de acht ontwerpprincipes voor organizational aesthetics zijn uitgewerkt in praktische object- en/of subjectgerichte interventies, waarmee organisaties per fase van bewustwording tot en met borging van esthetische waarde morgen aan de slag kunnen. Én waarmee tevens een nieuw en breder repertoire van interventies wordt aangereikt voor organisatie- en prestatieverbetering. cv steven de groot about the author steven de groot was born on july in geldrop. he was educated as a product designer at the design academy in eindhoven. hereafter, he studied educational and learning sciences for two years at the university of utrecht and received a grade for a master of business administration (mba) at the business school nederland (bsn). after working for fifteen years as a business consultant in the field of knowledge management and design of professional organizations, he did research at the universities of wageningen and tilburg. here the idea was born for starting research on organizational aesthetics. after doing some initial research on this field of interest in , the technische universiteit eindhoven offered steven the possibility to start in with his phd dissertation. steven can be contacted at: sdegroot@kultifa.nl e r r a t u m erratum to: beauty will save the world, but will the world save beauty? the case of the highly endangered vavilovia formosa (stev.) fed. aleksandar mikić • petr smýkal • gregory kenicer • margarita vishnyakova • nune sarukhanyan • janna a. akopian • armen vanyan • ivan gabrielyan • iva smýkalová • ekaterina sherbakova • lana zorić • jovanka atlagić • tijana zeremski-škorić • branko ćupina • Ðord̄e krstić • igor jajić • svetlana antanasović • vuk Ðord̄ević • vojislav mihailović • alexandr ivanov • sergio ochatt • cengiz toker • bojan zlatković • mike ambrose published online: september � springer-verlag berlin heidelberg erratum to: planta doi . /s - - - this erratum is addressing the reuse of four figures without the proper acknowledgement of the original source. figures , , and in this article were reproduced from the work of mikić, a., smýkal, p., kenicer, g., vishnyakova, m., sarukhanyan, n., akopian, j., vanyan, a., gabrielyan, i., smýkalová, i., sherbakova, e., zorić, l., atlagić, j., zeremski-škorić, t., ćupina, b., krstić, Ð., jajić, i., antanasović, s., Ðord̄ević, v., mihailović, v., ivanov, a., ochatt, s. and ambrose, m. ( ), the bicentenary of the research on ‘beautiful’ vavilovia (va- vilovia formosa), a legume crop wild relative with taxo- nomic and agronomic potential. botanical journal of the linnean society, volume , issue: , pages: – , by kind permission from john wiley & sons, inc. the online version of the original article can be found under doi: . /s - - - . a. mikić (&) � j. atlagić � t. zeremski-škorić � v. Ðord̄ević � v. mihailović institute of field and vegetable crops, maksima gorkog , novi sad, serbia e-mail: aleksandar.mikic@nsseme.com; aleksandar.mikich@gmail.com p. smýkal palacký university at olomouc, olomouc, czech republic g. kenicer royal botanical garden edinburgh, edinburgh, uk m. vishnyakova state scientific centre n.i. vavilov all-russian research institute of plant industry of russian academy of agricultural science, st. petersburg, russia n. sarukhanyan � a. vanyan green lane agricultural assistance ngo, yerevan, armenia j. a. akopian � i. gabrielyan � e. sherbakova national academy of sciences, institute of botany, yerevan, armenia i. smýkalová agritec plant research ltd., šumperk, czech republic l. zorić department of biology and ecology, faculty of sciences, university of novi sad, novi sad, serbia b. ćupina � Ð. krstić � i. jajić � s. antanasović department of field and vegetable crops, faculty of agriculture, university of novi sad, novi sad, serbia a. ivanov botany department herbarium, stavropol state university, stavropol, russia s. ochatt inra, umr , pcmv, dijon, france c. toker akdeniz university, antalya, turkey b. zlatković department of biology and ecology, faculty of sciences and mathematics, university of niš, niš, serbia m. ambrose department of crop genetics, john innes centre, norwich, uk planta ( ) : doi . /s - - - http://dx.doi.org/ . /s - - - erratum to: beauty will save the world, but will the world save beauty? the case of the highly endangered vavilovia formosa (stev.) fed. erratum to: planta doi . /s - - - isovector and hidden-beauty partners of the x( ) physics letters b ( ) – contents lists available at sciencedirect physics letters b www.elsevier.com/locate/physletb isovector and hidden-beauty partners of the x ( ) hallstein høgaasen a, emi kou b, jean-marc richard c,∗, paul sorba d a department of physics, university of oslo, box , no- oslo, norway b laboratoire de l’accélérateur linéaire, université paris-sud, in p -cnrs, centre scientifique d’orsay, orsay cedex, france c université de lyon, institut de physique nucléaire de lyon, ucbl–in p -cnrs, , rue enrico fermi, villeurbanne cedex, france d lapth, laboratoire d’annecy-le-vieux de physique théorique, cnrs, université de savoie, bp , annecy-le-vieux cedex, france a r t i c l e i n f o a b s t r a c t article history: received december received in revised form march accepted march available online march editor: g.f. giudice keywords: multiquarks exotic hadrons chromomagnetism the isovector partners of the x ( ), recently found at bes iii, belle and cleo-c were predicted in a simple model based on the chromomagnetic interaction among quarks. the extension to the hidden- beauty sector is discussed. © published by elsevier b.v. this is an open access article under the cc by license (http://creativecommons.org/licenses/by/ . /). funded by scoap . . introduction recently, a new hidden-charm meson was seen at bes iii and belle [ , ]. its remarkable feature, as compared to most previous x , y , z states is that it carries an electric charge. it is currently named x ( )+. shortly after its announcement, its existence was confirmed by the northwestern group working on cleo-c data [ ], who also have some indication for the neutral member of the isospin triplet. note that three other charged states with hidden charm have been observed, z ( )+ , z ( )+ and z ( )+ , but only by the belle collaboration. the z ( )+ and z ( )+ have been seen by belle in the b decay [ ], but not confirmed in a search by babar [ ]. the z ( )± was seen by belle in the π ±ψ ′ in- variant mass of the b → k π ±ψ ′ decay [ , ], and the quantum numbers + are favoured [ ]. to our knowledge, this state was not confirmed in other channels or other experiments. two charged states have been seen in the hidden-beauty sector, the zb( ) ± and the zb( )± , again by the belle collabora- tion [ ]. the latest result deals with the zb( ) discovered by belle [ ], the neutral partner of the zb ( ) ± . the x ( ) has j p c = ++ as early indicated in several exper- iments (see, e.g., [ ]), and confirmed recently at the large hadron collider of cern (lhc) (see, e.g., the analysis by lhcb [ ]). the * corresponding author. e-mail addresses: hallstein.hogasen@fys.uio.no (h. høgaasen), kou@lal.in p .fr (e. kou), j-m.richard@ipnl.in p .fr (j.-m. richard), paul.sorba@lapth.cnrs.fr (p. sorba). http://dx.doi.org/ . /j.physletb. . . - /© published by elsevier b.v. this is an open access article under the cc simplest scenario is that the new x ( )+ has the same j p quantum numbers as the x ( ), namely j p = +. a major issue is whether the x , y and z states are mostly molecules, i.e., bound states or resonances made of a flavoured meson and an anti-flavoured meson, or mostly a tetraquark states in which the quark interact directly. an analysis of the produc- tion rate of x ( ) in [ , ] indicates that the measured cross section at tevatron is too large for a molecule interpretation, even after taking into account the re-scattering effect suggested in [ ]. the problem is to find a simple explanation for the approx- imate degeneracy of the isospin i = and i = states. in the molecular model, the x ( ) is mainly a d d̄∗ + c.c. state, and an important contribution to binding comes from the one-pion ex- change, which includes an isospin-dependent factor τ .τ whose absolute value is weaker for i = than i = . in short, the molecular model of x , y , z states favours isospin i = states, as did earlier the nucleon–antinucleon model of the baryonium reso- nances [ ]. on the other hand, the quark model with a flavour-independent interaction gives a natural explanation to “exchange-degeneracy”, with, e.g., ω and ρ exactly degenerate as long as the quark– antiquark internal annihilation and the coupling to decay channels there is also a change of sign for τ .τ , which is + for i = and − for i = , but the pion-mediated interaction is off-diagonal in the {d d̄∗, d∗ d̄} basis, and thus the attractive or repulsive character depends on which of the d d̄∗ ± d∗ d̄ combi- nation is considered. by license (http://creativecommons.org/licenses/by/ . /). funded by scoap . http://dx.doi.org/ . /j.physletb. . . http://www.sciencedirect.com/ http://www.elsevier.com/locate/physletb http://creativecommons.org/licenses/by/ . / mailto:hallstein.hogasen@fys.uio.no mailto:kou@lal.in p .fr mailto:j-m.richard@ipnl.in p .fr mailto:paul.sorba@lapth.cnrs.fr http://dx.doi.org/ . /j.physletb. . . http://creativecommons.org/licenses/by/ . / http://crossmark.crossref.org/dialog/?doi= . /j.physletb. . . &domain=pdf h. høgaasen et al. / physics letters b ( ) – are neglected. thus if the x ( ) and the x ( )+ have the same j p , it is tempting to seek an explanation in terms of quark dynamics, rather than in a molecular picture. indeed, some mod- els based on quark dynamics have predicted the isospin i = state x ( )+ near its i = partner x ( ). this is the case for the chromomagnetic model discussed below and for the diquark model of ref. [ ]. this property of exchange degeneracy illustrates the similari- ties and differences between qed and qcd. after the work of de rújula, georgi and glashow [ ], it has become widely ac- cepted that the pattern of spin–spin splittings in quark models is similar in structure to that of the hyperfine splittings in atomic physics, namely is due to an interaction among chromomagnetic moments. in the case of the positronium atom, the interaction between the magnetic moments explains only about half of the en- ergy difference between the spin-triplet and the spin-singlet states. the hyperfine splitting in positronium receives a substantial contri- bution from the annihilation diagram where the electron–positron pair goes into a single virtual photon and back to an electron– positron pair. for the usual quark–antiquark mesons, there is no such effect, as the gluon transforms as an octet in colour. but the effect can show up for multiquarks, in which a quark–antiquark pair can be in a colour octet state. we shall discuss later the role of the pirenne potential, when suitably adapted from qed to quark models. the aim of this article is to revisit how the isospin i = part- ner of the x ( ) was predicted in a simple model [ ], and to discuss to which extent the model can be extended toward the hidden-beauty sector. . the x ( ) and the x ( )+ in a chromomagnetic model some years ago, three of us proposed a simple model for the x ( ) state, described as a (cc̄qq̄) tetraquark [ ], in which both the (cc̄) pair and the (qq̄) pair are mostly in a colour-octet state. this structure prevents the state from dissociating freely into a charmonium and a light meson. more precisely, the dynamics of the (cc̄qq̄) in [ ] is governed by the chromomagnetic hamiltonian h = m + h cm = ∑ i mi − ∑ i, j c i j λ̃i · λ̃ j σ i .σ j , ( ) where the mi are effective quark masses including the chromo- electric effects, and λ̃i and σ i the colour and spin operator acting on the ith quark, with suitable changes for an antiquark. should one start from an explicit potential model, then ∑ i mi would stand from the expectation value of the mass and kinetic-energy term, and the last term in ( ) represents the expectation value of the spin–spin interaction. thus c i j includes the intrinsic strength of the chromomagnetic potential divided by the quark masses, and multiplied by the short-range correlation of the quarks i and j. in principle, these terms should vary from a ground state hadron to another one. an empirical observation is that the quantities mi and c i j are nearly constants for i or j denoting u, d, s or c, suggesting the possibility of extrapolating from simple to more complicated configurations. a good surprise in our attempt [ ] is that one of the eigenstates of ( ) has some of the key properties of x ( ). moreover, ref. [ ] contains a prediction for the isospin i = partner of x ( ), at mev. in the discussion following eq. ( ) of [ ], it is stated that “the mostly i = state lies mev of course, in case of identical quarks, the pauli principle can induce some isospin dependence from the spin dependence. this is the reason why the Λ baryon is lighter than the Σ one. but here, this effect is not present, as isospin is carried by a quark and an antiquark. above the mostly i = state”. this calculation includes a mixing effect, as the quark masses mu and md are taken to be different. in the neutral sector, the i = and i = states are left degenerate by the chromomagnetic hamiltonian ( ). introducing the contribution of the annihilation diagram and different masses for the u and d quark give an additional contribution in the {(cc̄uū), (cc̄dd̄)} basis which reads δ h = ( mu − a −a −a md − a ) . ( ) we now have to fix the value of the parameter a governing the annihilation term. in the positronium atom, the virtual pro- cess e+ + e− → γ → e+ + e− contributes to the hyperfine splitting, in addition to the breit–fermi interaction. the effect is given by the pirenne potential [ ]. its strength is three times that of the breit–fermi contact interaction. the analogue for qcd has been discussed in the context of studies on baryonium and other ex- otic states [ – ]. in the perturbative limit, there is an additional factor due to colour, besides the factor in qed. however, as stressed by gelmini, the annihilation is substantially suppressed by the confinement of the gluons. so, instead of a = cqq̄ , a choice a ∼ cqq̄ is reasonable. in [ ], the values a = mev and md − mu = . mev were adopted, leading to a difference of about mev between the two eigenvalues, leading the prediction of about mev for the neu- tral i = partner of the x ( ). for the charged states of the i = multiplet, δ h is simply re- placed by mu + md , and this puts the charged states about . mev below the neutral, mostly isovector, one. . extension to the hidden-beauty sector the difficulty in our model ( ) consists in identifying a sin- gle effective mass for a flavoured quark in open-flavour mesons, flavoured baryons and hidden-flavour mesons. the combinations (q q̄)s= + (q q̄)s= = m q + mq, Σ ∗q + Σq + Λq = m q + mq, (q q̄ )s= + (q q̄ )s= = m q , ( ) should be compatible, and in particular, one should verify δm = (q q̄)s= + (q q̄)s= − Σ ∗q − Σq − Λq − (q q̄ )s= − (q q̄ )s= = . ( ) in the charm sector, one gets δm � − mev, which is rather sat- isfactory, but for the beauty sector, the result is δm � mev. it indicates that the bottomonium states give an average quark mass mb = mev, much lighter than the combination mb = ( b∗ + b − Σ ∗b − Σb − Λb )/ = mev deduced from heavy-light systems. this is due to the strong chromoelectric at- traction between two heavy quarks in (bb̄). we thus generalize our model to include a chromoelectric term, and replace ( ) by h = m + h ce + h cm = ∑ i mi − ∑ i, j ai j λ̃i · λ̃ j − ∑ i, j c i j λ̃i · λ̃ j σ i .σ j . ( ) introducing a few non-vanishing chromo-electric coefficients ai j implies a change of the effective masses. a minimal solution is found with mq = mev, mc = mev, mb = mev, and all ai j = , except for abb = mev by fitting the spin-averaged ground-state masses of (cc̄), (cq̄), (cqq) and the c → b analogues. h. høgaasen et al. / physics letters b ( ) – table colourmagnetic hamiltonian −h cm in the basis ( ). ⎡ ⎢⎢⎢⎢⎢⎢⎢⎢⎢⎣ c − c √ (c + c ) − c + c √ (c + c ) − (c + c ) √ (c − c ) √ (c + c ) c − c c − c √ (c + c ) c − c − c + c √ (c − c ) ( c + c + c + c ) ⎤ ⎥⎥⎥⎥⎥⎥⎥⎥⎥⎦ table parameters of the model: masses mi , non-vanishing chromoelectric ai j and chro- momagnetic c i j coefficients (in mev). mq mc mb abb cqq cqc ccc cqb cbb . . . table masses or mass differences of ground state hadrons in the model (in gev). state j /ψ j /ψ − ηc d d∗ − d Λc Σc − Λc Σ ∗c − Σc exp. . . . . . . . model . . . . . . . state Υ Υ − ηb b b∗ − b Λb Σb − Λb Σ ∗b − Σb exp. . . . . . . . model . . . . . . . a slightly better agreement is found by allowing both acc or abb to be non-zero, but we shall keep the minimal solution. we use the basis defined in [ ], namely α = (q q ) ⊗ (q q ) , α = (q q ) ⊗ (q q ) , α = (q q ) ⊗ (q q ) , α = (q q ) ⊗ (q q ) , α = (q q ) ⊗ (q q ) , α = (q q ) ⊗ (q q ) , ( ) where the superscript denotes the colour or , and the subscript or denotes the spin, with an overall recoupling to a colour- singlet j p = + state. the matrix elements of the colour-magnetic part have been given in [ ], and are reminded in table for completeness. one should now supplement it by the matrix elements of the chromo-electric term, which are h ce = ⎛ ⎜⎜⎜⎜⎜⎝ xa xb xa xb xa xb xb xc xb xc xb xc ⎞ ⎟⎟⎟⎟⎟⎠ , ( ) with xa = − ( a + a ), xb = √ ( a + a − a − a ), xc = ( a + a ) − ( a + a ) − ( a + a ) . ( ) the parameters are summarized in table . the ground-state masses of heavy quarkonia and heavy light mesons obtained using these parameters are listed in table . results the hamiltonian is now diagonalized, using the parameters of table fitting some ground-state ordinary hadrons containing the same quarks, q, c, b and the associated antiquarks. in the (cc̄qq̄) sector, one obtains results identical to the ones reported in [ ], with in particular, a state of mass very close to mev which is a pure α state. it was then argued that if cq̄c is taken slightly larger than cqc , then a small α component is admixed, that is responsible for the observed decay of x ( ) into j /ψ and a light vector meson. in our model, when the wave function is expressed in the (cq̄)(c̄q) basis, it has a large colour- singlet–colour-singlet component which corresponds to a decay into d d̄∗ or c.c., which is, however, strongly suppressed by the lack of phase-space for the x ( ). the x ( )+ is less known experimentally. we refer to a very recent review by olsen [ ]. the width is given as ± mev. the decay proceeds mainly through d d̄∗ + c.c., and benefits for this channel from a much more favourable phase-space than for the x ( ) [ ]. our model predicted a dominance of this decay into a charm-carrying vector plus a charmed pseudoscalar config- uration when phase-space opens up. in contrast to what happens for the x ( ), this superallowed decay becomes more important than the decays into (cc̄) + (qq̄). in this latter sector, the discovery channel of the x ( )+ was j /ψ + π . in our model, as in the case of the x ( ), introducing cq̄c = cqc generates a small α component in the wave function of the x ( )+ that induces a decay into j /ψ and a charged vector meson. the j /ψ + π decay involves an α component that is not provided in our simple model. similarly, a decay involving ηc would require an α component, or a spin-flip in the decay, which is suppressed, as discussed, e.g., in [ ]. in the hidden-beauty sector, one gets an analogue state of mass about . gev, and a wave function ∑ i bi αi with {bi } ∝ { , , , , , }. this means that this is a pure octet–octet state, so that the fall-apart decay into (bb̄) + (qq̄) is suppressed. this state is about mev above the b b̄∗ threshold, and thus slightly more un- stable with respect to this threshold, as compared to the x ( ) with respect to the d d̄∗ threshold. as for the x ( ), introducing some departure from cbq = cbq̄ would induce a small component consisting of a j /ψ and a light vector meson. as the breaking of exchange degeneracy and isospin symmetry occurs through light quarks, we except the same spacings between isospin i = and i = as in the hidden-charm sector, and same spacing among the neutral and charged states in the i = triplet. note that for the quartet of (bb̄qq̄) states predicted near . gev, the chromoelectric term gives a repulsion of about mev. as, e.g., when deriving the short-range part of the nucleon–nucleon interaction [ ], estimating the masses and prop- erties of multiquark states implies some speculation on the colour dependence of the effective interaction. the chromoelectric term in eq. ( ) corresponds to a colour-octet exchange, which is the most this paper was posted after the first version of the present article. h. høgaasen et al. / physics letters b ( ) – reasonable choice for a pairwise interaction, as a colour-singlet ex- change would confine everything together. but multi-body forces could be envisaged in more complicated models. . summary and conclusions in this article, it was reminded that a simple quark model [ ] predicted the existence of an i = partner of the x ( ) at the right mass and thus anticipated the recent discovery by bes iii, belle and cleo-c [ – ]. the model consisted of effective masses and a chromomagnetic interaction. it can be supplemented by a minimal chromoelectric term and then applied to the sector of states with hidden-beauty. the model predicts a nearly degenerate quartet (an i = sin- glet and an i = triplet, with some mixing of the neutrals) near . mev. the charged states are possible candidates for either the zb( ) ± or zb( )± states of belle [ ]. it is, however, very difficult in this approach to produce an isospin i = state without a nearby i = partner, and to arrange two nearly degen- erate isotriplets. it seems important to use the most advanced accelerators and detectors to investigate this sector of hadron physics. the belle ii facility [ ] will of course provide us with crucial information. but the search is already active at the lhc, with in particular, a very recent search for the xb by the cms collaboration [ ], with no evidence in the Υ ( s)π +π − channel. it is hoped that the com- bined efforts at lepton and hadron colliders will definitely clarify the situation in the hidden-beauty sector. acknowledgement we thank b. grinstein for a useful correspondence. references [ ] m. ablikim, et al., bes iii collaboration, phys. rev. lett. 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[ ] s. chatrchyan, et al., cms collaboration, arxiv: . , . http://refhub.elsevier.com/s - ( ) -x/bib c b d a d fs http://refhub.elsevier.com/s - ( ) -x/bib c b d a d fs http://refhub.elsevier.com/s - ( ) -x/bib c a s http://refhub.elsevier.com/s - ( ) -x/bib c a s http://refhub.elsevier.com/s - ( ) -x/bib f a s http://refhub.elsevier.com/s - ( ) -x/bib d a b a d s http://refhub.elsevier.com/s - ( ) -x/bib d a b a d s http://refhub.elsevier.com/s - ( ) -x/bib c a bs http://refhub.elsevier.com/s - ( ) -x/bib c a bs http://refhub.elsevier.com/s - ( ) -x/bib f a s http://refhub.elsevier.com/s - ( ) -x/bib f a s http://refhub.elsevier.com/s - ( ) -x/bib d a b a s http://refhub.elsevier.com/s - ( ) -x/bib d a b a s http://refhub.elsevier.com/s - ( ) -x/bib c b e a s http://refhub.elsevier.com/s - ( ) -x/bib c c a s http://refhub.elsevier.com/s - ( ) -x/bib c c a s http://refhub.elsevier.com/s - ( ) -x/bib b f b f e a d s http://refhub.elsevier.com/s - ( ) -x/bib e a a as http://refhub.elsevier.com/s - ( ) -x/bib d e a a d s http://refhub.elsevier.com/s - ( ) -x/bib e d e a bs http://refhub.elsevier.com/s - ( ) -x/bib e d e a bs http://refhub.elsevier.com/s - ( ) -x/bib e d e a es http://refhub.elsevier.com/s - ( ) -x/bib f e a bs http://refhub.elsevier.com/s - ( ) -x/bib b a s http://refhub.elsevier.com/s - ( ) -x/bib e a c s http://refhub.elsevier.com/s - ( ) -x/bib a c a s http://refhub.elsevier.com/s - ( ) -x/bib f e a a s http://refhub.elsevier.com/s - ( ) -x/bib f e a a s http://refhub.elsevier.com/s - ( ) -x/bib e e a s http://refhub.elsevier.com/s - ( ) -x/bib f e a s http://refhub.elsevier.com/s - ( ) -x/bib f e a s http://refhub.elsevier.com/s - ( ) -x/bib f e a s http://refhub.elsevier.com/s - ( ) -x/bib e a as http://refhub.elsevier.com/s - ( ) -x/bib c d e a s http://refhub.elsevier.com/s - ( ) -x/bib f c e a d s http://refhub.elsevier.com/s - ( ) -x/bib c b d a s http://refhub.elsevier.com/s - ( ) -x/bib c b d a s http://refhub.elsevier.com/s - ( ) -x/bib f c f e a d s http://refhub.elsevier.com/s - ( ) -x/bib a s http://refhub.elsevier.com/s - ( ) -x/bib b f a d as http://refhub.elsevier.com/s - ( ) -x/bib b f a d as http://refhub.elsevier.com/s - ( ) -x/bib e a d s isovector and hidden-beauty partners of the x( ) introduction the x( ) and the x( )+ in a chromomagnetic model extension to the hidden-beauty sector results summary and conclusions acknowledgement references to dr. alfred metraux the writer wishes to express his appreciation for helpful sugges~ tions made after reading this paper in manuscript. or bad. gripped as we are with the romance of the noble savage, what little we know of culture history shows that change has been ever present- carib has succeeded g~, arawak has succeeded or influenced carib, and so on. if we are realistic in our studies of culture we know that change is universal and we cannot and should not seek refuge only in the study of past changes. it seems that changes in the next to years in the tropi- cal forest area will be more significant and more far-reaching from the point of view of the human species in general than any that have gone before. n- thropologists cannot afford to ignore them. ohio state university colum jus, ohio american anthropowgist [n. s., , professional beauties of normanby island by gltza r heim n ormanby island has a group of women and men whom we canonly describe as professional beauties. doketa, my wari eas ("song name", i.e. namesake) gave the following detailed accounts of these: . from sawatupwa to sigasiga the people are manibus (man in the b!lsh). they don't know this kind of thing. the people of tubetube, duau, dobu and-ferguson island know them. . . the old people liked the gomabwaina (male beauties). their gro'?"th -had to be perfect from top to toe. it was an important point that the body should be slender, . with the breast and trunk broad but the waist narrow. their hands should not be very thin. face and nose should be just right (paru-paruna). their hair should be neither small nor big but just average and this kind of hair was called kujagiliatu (hair hard). gomabwaina must behave in cer:tain ways. they d&n't eat much and they don't go to steal women. they don't joke and they don't deal-with 'things in a straight- forward way. omajamaja (shame) is specially emphasized in their case. if they do go courting at least they don't put decorations on (feathers, paint, etc.) and they don't tatoo their bodies. they should marry only 'sinebwaina (female beauties) .. however so.:rtl,e of them do marry ugly women because the latter have big gardens~ in these cases the male beautyjs-friends-will object and tell him to leave his ugly wife and marry one of the beauties. but he will reject them and stick to his wife, who takes good care of him. at the time of my visit to n ormanby island these gomabwainas were evidently a thing of the past. none of my informants could mention a single person then alive who had been one. "male beauties" seem to have been a secondary institution, possibly an imitation of the more important "female beauties" pattern. male beauties had no distinctive patterns of sexual be- havior. the main thing about them was that their group was proud of them. on this account the capture of a gomabwaina meant glory and was the supreme aim of all war parties. a story will illustrate this: masasa was a gomabwaina at gudamuri. the dobu people came and captured him and put him in a canoe. his brother followed them, running along the shore and crying. he shouted to them, "let masasa go back and take me!" they re- plied, "n , we want him. you go back and look after your village."" the narrator concluded: "such a beautiful man has never been seen." doketa's account of the female beauties was as follows: the growth of a sinebwaina is neither tall nor short but just right from top to toe. the side of her body is weliweli (lit. "straight round"). her trunk. is narrow with small but prominent breasts. teeth, face;, vulva and pubic hair should all be small. they should not eat much because then they will be big and altho ugh they may still be beautiful in the ordinary sense of the word, if they are no t small enough they cease to be sinebwaina. in this case they are kesaejana (middii ng ones). sinebwaina should not laugh loud or hang about but they should stop at home with their mother or sister. itis an important point that they must have intercourse with all men who desire them. the peculiar thing about them is th at they must do nothing (like laughing) which might be regarded as in invitation. id i lojawe kapana inugeta "their love making coitus first". while other women have first the kenokeno (sleeping with their boy friends without taking their skirts off) a sinebwaina will begin acquaintance by having intercourse. after the first coitus t hey will lie with the man like other women. they don't marry anybody but w ait for an esaesa (rich man). gimwagimwareja, now a widow with a decided reputation for be ing a sogara (woman who desires men) says that the sinebwaina does no t care to have intercourse with everybody, especially not with ugly men. w hen the gwari (group of men going from house to house in search of a girl) c omes she only accepts pretty men. sinebwaina do not smile and they should be small. they eat very little in order to remain thin, only half a yam a day . there is a great difference between a sogara and a sinebwaina . the sogara, who is regarded as we regard prostitutes, is a woman who takes the initiative. she goes to a man or follows him. there is also a great d ifference between a sinebwaina and a sine-kubu-kubu toa (lit. ((woman botto m stop") who is her antithesis. the latter is a woman so ugly that she av oids men through fear that the people will make jokes about her. the sine bwaina is passive but assured of her charms. "ordinary women have bad vu lvas and so are ashamed but the sinebwaina has a good vulva and so giv es it for nothing. ordinary women frequently reject us, but a sinebwain a always wants intercourse when she sleeps with a man." the last refers to courting customs; women will frequently sleep with men without having intercours e. the sinebwaina sits at home in her house. whoever comes to her, y oung or old, she accepts because if she refuses anybody she is not a sineb waina, she cannot tell them to go back because her fame would suffer. wh en away from home she will not talk to anybody and will run away from pe ople who laugh. however, if a man finds her on the road he will catch hold of h er and say "today i will come to you!" "very good", she replies. then the man gives her shell money. she will be ashamed or angry if people c all hera sinebwaina openly but will be glad if she overhears them doing so . she will:, say to her lovers: '(let us have intercourse and then the men will t alk about me and the people will hear my name." a somewhat similar institution seems to exist in the trobriands, where [roheim] plate ne dojara "professional beauties of normanby island" american anthropologist, n. s., vol. [n. ., , american anthropologist from a dobu informant who spent several years at kiriwina. b. malinowski, the sexual life of sa jages in northwestern melanesia, ( ), pp. , . such women are called naminabaita. having a daughter who is naminabaita is connected with the custom of ula tilava (paying for compliments). a man goes to another and says: "your daughter is a beauty!" the father must give him something or he will take the child.] the same rule holds if a man is good at carving or dancing and another tells him that he is. . ne dojara, a woman who used to be a sinebwaina, related the story of her life as follows: "we had sapisapi (shell string necklaces) and a;ne (scented flowers). mother told me i was a sinebwaina. i was not to eat t.oo much and i was to eat little pieces only. when my mother died, father told me that i was not to marry a male beauty (gomabwaina) but a good gar- dener. but i wanted mauitu only. i think he made a sigaha (love magic) but i don't know. while i was a sinebwaina i never laughed and i did not walk about with other women. i always just sat in the house. this is the way of a sinebwaina." a dream told by the same woman may throw some light on the psychol- ogy of the sinebwaina: "i dreamed about my sister's daughter, sine wenaki. young men were having intercourse with her, especially kamulesi. he said: 'i have not had intercourse with her.' they were awake; it was dawn. her father scolded kamulesi. 'you should not have had intercourse with my daughter l' he replied: 'our women grow ·up, they are nice and we make love to them.' then they looked for kaira (shells) and they gave them to her father." the associations of this dream are as follows: first' she explains what kind of a girl sine wenaki, her sister's daughter, is. she always says to the boys: ((there go my husbands. i wish they would give me tobacco." the boys reply: >'you are our wife. we shall bring you tobacco." of- "we give you tobacco and we are coming today." her father always said: "she thinks only of the gwari (group of boys in search of a girl) and does not work in the garden." when kamulesi, a totem sibling, wanted to marry her, her father kept her back. "then you will leave me," he said. but her mother was in favor of the marriage and sent kamulesi to fetch shells to begin the marital exchange of presents. on the other side kamulesi's elder brother was trying to delay the marriage. he said, "don't hurry. the girl should grow up first." these are the same words used by kamulesiin the dream. the dream sentence therefore means that kamulesi is jtistifying himself; the time has come when his elder brother (here identified with the girl's father) would also agree to his marriage. robeim] professional beauties of normanby island professional beauties of normanby islandr hei:m] minated their period of mourning and are now coming out of the jungle into the village. they are washed, oiled and decorated and the girls are expected to fall in love with them. sticking in the streamer oh streamer of tauhau! i stick it in. oh streamer of tauhau! i plait it. i make light and i gather them! married women and girls for them i plait the streamer. i make light, i gather them. the breasts i desire, the black nipples! i make light, i fetch them. o daughters of chiefs! i make light, i fetch them. child lying beginning child lying on a pillow! the rest of the incantation does not intej;est us here. the informant ex- plained that n atu kabakaba kuna, "child lying beginning" and n atu kaba- kaba gedu "child lying on a pillow," were terms for a real sinebwaina, since she always lies in the house and sleeps, like a child. the oljvious conjecture is that the sinebwaina is playing the role of a childj that the beauty ideal represents infantilism. moreover, if we observe that the passive element is stressed in her attitude we should interpret this class of professional beau- ties as representing passive object love in ferenczi's sense. "i am only a little girl. all i desire is to be beautiful, beloved and famous," would be her for- mula. the two latter concepts are manifestly identical. this would agree very well with the cultural pattern of this area. they are always saying that they are merely children, i.e. denying adult aggression. in this case it seems that the beautiful girls are denying their mother-daughter rivalry in the marked passivity and in the emphasis laid on an infantile appearance. the sinebwaina is trying to make everyone believe she is only a little" girl. in her behavior, however, she shows exactly the opposite pattern. for her there is no playful fore-pleasure, only adult genital "sexuality. vvorcester,~assachusetts he makes light because the sun gleams on his streamer. [n. s" , american anthropowgist after this, without transition, ne dojara begins to talk about herself. "my father told me, 'don't marry quickly, you will leave me.' mother said, 'marry quickly, i want to eat tjie pokara (marriage present).' my father was my real friend, my mother was my enemy." her oedipus complex is nearly conscious. she identifies herself with her sister's daughter, in whose case the situation was the same. she next talks about kamulesi and describes him as a serious sort of person who does not care for flirtation and on the other hand as a man with a strong mother fixation. when women were joking with him he said: hi work in my mother's garden. when she dies i will marry." his mother told the girls he would marry only after her death. sometimes she advised him to marry but he always replied that he would stay alone with his mother. ne dojara then talks about events that happened at madarabuna on the shore of wejoko at a sagari (food distribution festival). kamulesi and kaubwagamo were gathering shells on the beach (as in the dream). they' had both come as muri (relatives-in-iaw). the women were jealous and quarreled with her. they were jealous because of her husband, tau louja. then she explains that kamulesi's words in the dream, literally "we did. not sleep", really mean "we did not cohabit." in the same way she an- '- swered the women by saying "i am married already". now if they had really been jealous about tau louja this reply is meaningless. but if they were accusing her of carrying on like a sinebwaina with kamulesi and kaub: wagamo, we can understand her reply. "i am not a j-inebwaina, i am mai-,':':', ned." having said this she rises, covers herself very carefully with her skirt;;} and leaves me. if ne dojara is the girl of her dream we must say that a sinebwaina',i,s"" really a woman who desires all men but who hides this under a maskqf passive behavior. for sine wenaki is certainly what the natives would <:am"" a sogara (aggressive woman). moreover, we also see that her desire for tli;:~ men is based on her oedipus complex. the men are all fathers (kamul~:' is a serious person) whom she is taking away from the mother (kamules~' mother fixation). a sinebwaina is therefore typically the ciaughter,t~c young woman in opposition to her mother. ,:' if we look at the sinebwaina attitude and beauty ideal from the cd tural point of view and interpret it without dream analysis, we notice emphasis laid on smallness, especially on small breasts. this is most' usual in a primitive group. one of the incantations obtained in connec with the gute (mourning ceremonies) at nadinadia confirms the interp:r:f:l tion of the sinebwaina as a child. it is used when the performers ceremony stick the pandanus streamers into their armlets. they wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ [pdf] the biological basis of mathematical beauty | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /fnhum. . corpus id: the biological basis of mathematical beauty @article{zeki thebb, title={the biological basis of mathematical beauty}, author={s. zeki and oliver y. ch{\'e}n and j. romaya}, journal={frontiers in human neuroscience}, year={ }, volume={ } } s. zeki, oliver y. chén, j. romaya published psychology, medicine frontiers in human neuroscience our past studies have led us to divide sensory experiences, including aesthetic ones derived from sensory sources, into two broad categories: biological and artifactual. the aesthetic experience of biological beauty is dictated by inherited brain concepts, which are resistant to change even in spite of extensive experience. the experience of artifactual beauty on the other hand is determined by post-natally acquired concepts, which are modifiable throughout life by exposure to different… expand view on pubmed frontiersin.org save to library create alert cite launch research feed share this paper citationsbackground citations view all figures, tables, and topics from this paper figure table figure figure figure figure view all figures & tables mathematics artifact (software development) categories spatial variability mike lesser national origin heart rate variability lichen sclerosus et atrophicus morphologic artifacts experience citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency the biological basis of the experience of constant colour categories s. zeki, alexandre javier, d. mylonas psychology, biology pdf view excerpts, cites background save alert research feed the biological basis of the experience and categorization of colour s. zeki, alexandre javier, dimitris mylonas mathematics, medicine the european journal of neuroscience pdf save alert research feed the default-mode network represents aesthetic appeal that generalizes across visual domains edward a. vessel, a. i. isik, amy m. belfi, jonathan l. stahl, g. starr psychology, medicine proceedings of the national academy of sciences pdf save alert research feed beauty in motion through the lens of doppler’s formula r. suleiman mathematics pdf view excerpt, cites background save alert research feed the bayesian‐laplacian brain s. zeki, oliver y. chén computer science, medicine the european journal of neuroscience pdf save alert research feed building long-term meaning in mathematical thinking: aha! and uh-huh! david. tall, david. tall pdf save alert research feed the bayesian-laplacian brain s. zeki, oliver y. chén biology, computer science pdf save alert research feed references showing - of references sort byrelevance most influenced papers recency the experience of mathematical beauty and its neural correlates s. zeki, j. romaya, dionigi m. t. benincasa, m. atiyah psychology, medicine front. hum. neurosci. pdf view excerpts, references background and methods save alert research feed stronger shared taste for natural aesthetic domains than for artifacts of human culture edward a. vessel, natalia maurer, alexander denker, g. starr psychology, medicine cognition view excerpts, references background save alert research feed toward a brain-based theory of beauty t. ishizu, s. zeki biology, medicine plos one pdf view excerpts, references background save alert research feed frontoparietal activation distinguishes face and space from artifact concepts chi-hua chen, s. zeki psychology, medicine journal of cognitive neuroscience pdf view excerpts, references background save alert research feed beauty in proofs: kant on aesthetics in mathematics a. breitenbach philosophy pdf save alert research feed the constancy of colored after-images s. zeki, samuel w cheadle, j. pepper, d. mylonas computer science, medicine front. hum. neurosci. pdf view excerpt, references background save alert research feed sense and sensibility in kant's practical agent: against the intellectualism of korsgaard and sidgwick j. wuerth philosophy save alert research feed the bayesian-laplacian brain s. zeki, oliver y. chén biology, computer science pdf view excerpts, references background save alert research feed xi. the relation between mathematics and physics p. dirac mathematics, physics save alert research feed introduction to mathematical philosophy b. russell philosophy , pdf view excerpt, references background save alert research feed ... ... related papers abstract figures, tables, and topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue pone. .. toward a brain-based theory of beauty tomohiro ishizu, semir zeki* wellcome laboratory of neurobiology and wellcome department of imaging neuroscience, university college london, london, united kingdom abstract we wanted to learn whether activity in the same area(s) of the brain correlate with the experience of beauty derived from different sources. subjects took part in a brain-scanning experiment using functional magnetic resonance imaging. prior to the experiment, they viewed pictures of paintings and listened to musical excerpts, both of which they rated on a scale of – , with being the most beautiful. this allowed us to select three sets of stimuli–beautiful, indifferent and ugly–which subjects viewed and heard in the scanner, and rated at the end of each presentation. the results of a conjunction analysis of brain activity showed that, of the several areas that were active with each type of stimulus, only one cortical area, located in the medial orbito-frontal cortex (mofc), was active during the experience of musical and visual beauty, with the activity produced by the experience of beauty derived from either source overlapping almost completely within it. the strength of activation in this part of the mofc was proportional to the strength of the declared intensity of the experience of beauty. we conclude that, as far as activity in the brain is concerned, there is a faculty of beauty that is not dependent on the modality through which it is conveyed but which can be activated by at least two sources–musical and visual–and probably by other sources as well. this has led us to formulate a brain-based theory of beauty. citation: ishizu t, zeki s ( ) toward a brain-based theory of beauty. plos one ( ): e . doi: . /journal.pone. editor: eric james warrant, lund university, sweden received march , ; accepted june , ; published july , copyright: � ishizu, zeki. this is an open-access article distributed under the terms of the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. funding: this work was supported by the wellcome trust, london. the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. competing interests: the authors have declared that no competing interests exist. * e-mail: zeki.pa@ucl.ac.uk introduction in the work reported here, we address a question that has been addressed many times over past centuries, namely what constitutes beauty. the question was especially well formulated, in a neurobiologically accessible way, by edmund burke. in his philosophical enquiry into the origin of our ideas of the sublime and beautiful, burke wrote that ‘‘beauty is, for the greater part, some quality in bodies acting mechanically upon the human mind by the intervention of the senses’’ [ ]. that definition suggests that there is a unique faculty of beauty that can be stimulated by any and all the senses. it thus raises an important question: would the experience of beauty derived from different senses, say the visual and auditory, correlate with activity in the same or different brain areas? if the latter, then the clear implication would be that brain systems that correlate with the experience of beauty are functionally specialized, the experience of visual beauty correlating with activity in one area or set of areas and that of auditory beauty correlating with another. but our reading of the relevant humanistic literature, too numerous to mention, suggests that the first alternative has been more favored by those who have discoursed on the subject, namely that there is a single faculty of beauty into which different senses feed. this alternative is reflected in burke’s definition. we thus sought to learn something, however small, about how brain activity might be organized during the experience of beauty. burke and many others, including immanuel kant, anthony ashley-cooper ( rd earl of shaftesbury) and joseph addison, distinguished between the beautiful and the sublime, the latter having for them characteristics such as ‘‘awe’’, ‘‘horror’’, ‘‘disgust’’ and ‘‘fear’’. in this work we are concerned with the beautiful alone, not the sublime. we undertook a human brain imaging experiment, using functional magnetic resonance imaging (fmri), in which we asked subjects to view pictures of paintings and listen to brief musical excerpts and rate them according to how beautiful they seemed, while we imaged the activity in their brains. as a working hypothesis, we inclined more towards our neurobiological understanding of burke’s definition and supposed that there would be a single area or set of areas whose activity would correlate with the experience of beauty, regardless of whether it was derived from an auditory or visual source. previous work from this and other laboratories [ – ] has implicated activity in the mofc-an acknowledged pleasure and reward center in the brain [ ]-during the experience of visual or musical beauty but no equivalent study for the experience of beauty derived from two different senses in the same subjects has been reported. this is important, since the mofc is a large expanse of cortex and different but sometimes overlapping parts of it have been activated by different tasks [ , ]. we hypothesized that activity in the same part of mofc would correlate with beauty in the more abstract sense, that is to say, regardless of whether it is derived from the auditory or visual sense. this turned out to be so and led us to formulate a brain-based theory of beauty. materials and methods subjects healthy right-handed volunteers ( male, female, mean age . years) participated in this study. all had normal or corrected-to-normal vision, and none had a history of neurological or psychiatric disorder. written informed consent was obtained from all, and the study was approved by the ethics committee of the institute of neurology. all data was anonymized. subjects plos one | www.plosone.org july | volume | issue | e were drawn from the following cultural groups: west europeans, americans, japanese, chinese and indian. except for one subject, none was an artist or a musician. psychophysical testing prior to scanning, psychophysical tests were used to select stimuli; this allowed subjects to classify stimuli into three groups- ‘beautiful’, ‘indifferent’ and ‘ugly’-which were subsequently shown in the scanning sessions. we first tested subjects ( male, female, mean age . years) who did not participate in the scanning. each viewed paintings and listened to musical excerpts. the visual stimuli included paintings of portraits, landscapes and still lifes, most of them from western art but three from oriental art. the auditory stimuli included classical and modern excerpts of mainly western music with two japanese excerpts. all stimuli were presented for s with an inter-trial interval of s. each stimulus was given a score from to . those given scores of – were classified as ‘ugly’, – were classified as ‘indifferent’ and – as ‘beautiful’. based on the psychophysical testing, we selected ‘beautiful’, ‘indifferent’ and ‘ugly’ stimuli in the visual and musical categories to be used for the scanning sessions, resulting in total of stimuli ( each for painting and music). during a first visit to the laboratory, between one and two weeks prior to scanning, each subject was instructed about the experiment and rated the stimuli as described above. only subjects classifying the stimuli into the three categories in roughly equal proportions were selected for the scanning experiment (see supporting information: table s . behavioral data collected in preliminary behavioral test). one subject, who classified all visual stimuli as ugly or neutral, was excluded. stimuli stimuli were generated using cogent (http://www.vislab. ucl.ac.uk/cogent_ ) running in matlab (mathworks, na- tick, ma, usa). as a counterpart to the evolving and therefore dynamic nature of the musical stimuli, each visual stimulus was made to zoom continuously at the rate of u sec , using image- editing programs (adobe h photoshop cs h , premiere pro cs h ). the visual stimuli were back-projected onto a screen using a lcd projector through an angled mirror. the resolution of the screen was , , pixels. participants listened to the auditory stimuli through headphones (mr confon, magdeburg, germany). the session began with subjects viewing a flat black screen for s to allow for t equilibration effects to subside (and the corresponding first six brain volumes were discarded). a fixation point was then presented at the center of the screen against a black background for s. this was followed by the presentation of visual or auditory stimuli, in random order, for s each, followed by an interval of s. when musical stimuli were presented, a fixation point appeared at the center of the black screen and participants were asked to fixate it. after each stimulus presentation, participants were asked to rate them into one of three categories–of ‘‘beautiful’’, ‘‘indifferent’’, or ‘‘ugly’’-using button presses with their right hand. as with the pre-scanning classification, we expressly asked subjects to rate their experience of the entire s period during which they were exposed to the stimulus. the response period lasted for s and participants could make their rating at any time during that period. the session ended with a blank period of s, during which the scanner continued to acquire blood oxygen level-dependent (bold) signals. the stimuli were presented in sessions, each consisting of stimuli, half of which were auditory and the other half visual–presented in pseudo-random order. each session contained three visual and three auditory stimuli. prior to the scanning, participants had a short practice session using different visual and auditory stimuli to those used in the scanning session. scanning details scanning data were acquired with a -t siemens magnetom trio mri scanner (siemens, erlangen, germany) fitted with a - channel head-coil. an echo-planar imaging (epi) sequence was applied for functional scans to obtain bold signal (echo time te = ms, repeat time tr = ms, volume time . s) using slices to cover the whole brain. the voxel resolution was mm mm in-plane resolution, with a mm slice thickness and mm inter-slice gap. t -weighted anatomical images were acquired at the end of experimental sessions for each subject ( slices, resolution mm, te = . ms, tr = . ms). we also recorded physiological responses, heart rate and breathing, for each subject. analysis all data were analysed using spm (statistical parametric mapping http://www.fil.ion.ucl.ac.uk/spm/software/spm /). the epi images for each subject were realigned and normalized into montreal neurological institute (mni) space, smoothed using gaussian smoothing kernel of mm, and filtered with a high- pass cutoff ( s) to remove drift terms. the stimulus for each subject was modelled as a set of regressors in a general linear model (glm) first-level (within subject) analysis. the stimulus was a block design and boxcar functions were used to define stimulus functions, which modelled the onsets and durations of the appearances of each of the visual and musical stimuli. key presses, modelled as delta functions, constituted an additional variable. head movement parameters calculated from the realignment pre-processing step and physiological recordings were included as regressors of no interest. stimulus functions were convolved with a canonical hemodynamic response function (hrf) to provide regressors for the glm. we carried out two separate analyses, categorical and parametric, encoding the same data in two different ways. for the categorical analysis, separate stimulus functions for beautiful, indifferent and ugly stimuli (based on the subject-specific responses) in each modality (visual and musical) were used. contrast images for both musical and visual presentations and beauty ratings were taken to second-level (between subject) t-tests to produce statistical maps at the group level. we also analyzed our data for parametric modulation, for which visual and musical stimuli given a beauty rating were used as regressors, with beauty rating as the parametric modulator. ratings were coded as - , and for ‘ugly’, ‘indifferent’ and ‘beautiful’, and a st order polynomial expansion was included. conjunction analyses [ ] were used to characterize brain activations common to visual and musical experiences designated as beautiful or otherwise. we report cluster level activations that were significant at p, . corrected, although some of these were also significant at the voxel level at p, . fwe (family wise error) corrected. in cases where we had a priori knowledge of an area’s involvement, we used a small volume correction (svc) of mm, p, . corrected at voxel level, using co-ordinates given in a previous study [ ]. results behavioral data table shows behavioral data collected in the scanning experiment. the proportion of stimuli which participants brain and beauty plos one | www.plosone.org july | volume | issue | e responded to as beautiful, indifferent or ugly in both visual and musical conditions is presented. since we were interested in the experience subjects had over the entire s of exposure to the stimuli, we specifically instructed them to respond only after the stimulus period ended. subjects could respond anytime within the s response period. beautiful . ugly our chief interest was to determine the cortical activity that correlates with experiences that were qualified as beautiful or ugly by the subjects. we therefore used the following contrasts: (a) beautiful . ugly for visual and musical stimuli; (b) beautiful . not beautiful, that is, beautiful . indifferent + ugly for visual and musical stimuli; (c) beautiful . indifferent for visual and musical stimuli. the results of these contrasts are given in table , which shows that (a) the contrasts visually beautiful . visually ugly led to activation in the mofc, at – , while musically beautiful vs. musically ugly led to activation in mofc at – (figure ); (b) the contrasts visually beautiful . visually indifferent + visually ugly led to activation in the mofc, at – and – (with the application of a mm svc), while the contrast musically beautiful . musically indifferent + musically ugly led to activation in the ofc at – (with the application of a mm svc); (c) the contrasts visually beautiful . visually indifferent led to activation in the mofc at – (with the application of a mm svc), while the contrast musically beautiful . musically indifferent led to activation in the mofc at – (with the application of a mm svc). the mofc was the only cortical area that was commonly activated by all these contrasts, although each contrast also showed other activations (summarized in table ). this naturally led us to the heart of our enquiry, which was to learn, through the application of a conjunction analysis, whether activity in the same part of the mofc correlated with the experience of visual and musical beauty. we used the following contrast for our conjunction analysis: [visually beautiful . visually ugly] and [musically beautiful . musically ugly]. this led to a significant conjunction in the mofc at – (p, . , corrected) using an svc of mm. the results are given in table . superimposing the activations derived from the contrast visually beautiful . visually ugly and musically beautiful . musically ugly (using mricron: http://www.cabiatl.com/mricro), showed that the areas of activation derived from the two contrasts overlap substantially, if not totally. thus the only common area activated by stimuli that were judged to be beautiful, regardless of whether they were visual or musical, was located in the mofc. we refer to this area as subdivision a of the mofc (see figure and discussion). to check for the possibility that it may take longer to comprehend or experience beauty derived from one source compared to the other, we analyzed the data from one representative subject further with respect to different times within the viewing period. the data from this subject was divided into periods, corresponding to , , , and s after stimulus onset. analyzing data from each time segment separately using boxcar functions, we found activity in mofc with musical stimuli in the first segments while with visual stimuli the activity in mofc was detected with the last three segments (p, . uncorrected). hence the mofc was active during most of the period of stimulus presentation for both visual and musical stimuli even if the activation induced by musical beauty was slightly earlier ( s) than that induced by visual beauty. we conclude that the s model that we have used with boxcar function is an appropriate model in this study. table . behavioral data collected in fmri study. stimulus modality beautiful indifferent ugly visual . % . % . % (range) ( . – . ) ( . – . ) ( . – . ) musical . % . % . % (range) ( . – . ) ( . – . ) ( . – . ) distribution of behavioral ratings during the scanning experiment by stimulus modality, averaged over all subjects. range shows maximum and minimum percentages among subjects. doi: . /journal.pone. .t table . activated areas correlating with the experience of beauty. brain regions l/r x y z t ke visually beautiful . visually ugly caudate nucleus l . medial ofc l . musically beautiful . musically ugly medial ofc l . visually beautiful . indifferent + ugly medial ofc (svc) r . medial ofc (svc) l . caudate nucleus l . caudate nucleus l . musically beautiful . indifferent + ugly medial ofc . visually beautiful . indifferent medial ofc (svc) r . visually ugly . indifferent no suprathreshold clusters musically beautiful . indifferent medial ofc (svc) r . musically ugly . indifferent supra marginal gyrus r . location, mni co-ordinates, cluster size and values for the activations produced by the contrasts: visually beautiful . visually ugly, musically beautiful . musically ugly, visually beautiful . visually indifferent + ugly, musically beautiful . musically indifferent + ugly, visually beautiful . visually indifferent, visually ugly . visually indifferent, musically beautiful . musically indifferent and musically ugly . musically indifferent. in this and subsequent tables, all activations are cluster level significant at p, . (corrected), although some of these were also significant at voxel level. where we had a priori knowledge of an area’s involvement, we applied a small volume correction (svc) of mm indicated as svc. doi: . /journal.pone. .t brain and beauty plos one | www.plosone.org july | volume | issue | e strength of activation in mofc we wanted to learn whether the strength of activation in the mofc is proportional to the strength of the declared experience of beauty, when viewing or listening to visual and musical stimuli. a parametric analysis of the relationship between intensity of experience and the bold signal showed that the activity was parametrically modulated within the mofc, for visual stimuli at – (p = . ) and for musical stimuli, with the application of a mm svc, at – (p = . ) (figure ). other activations in the contrast beautiful . ugly besides the mofc, the body of the caudate nucleus, which has been shown to be active in a variety of emotional states, including the viewing of a loved romantic partner [ ] and the experience of beauty [ ], was also significantly active (table ). ugly . beautiful the inverse contrast, ugly . beautiful, led to activation in a number of areas, summarized in table . the contrast visually ugly . visually beautiful led to activation in left and right figure . cortical activation correlating with the experience of beauty. statistical parametric maps rendered onto averaged anatomical sections (average of subjects) showing the t statistic for the contrasts (a) visually beautiful . visually ugly, (b) musically beautiful . musically ugly and (c) the results of a conjunction analysis for visually beautiful . visually ugly and musically beautiful . and musically ugly. upper row shows activity in mid-saggital sections and the middle row in horizontal sections of the brain. (d) shows the overlap in zones within the medial orbito-frontal cortex (mofc) activated by visually beautiful (red), musically beautiful (green) stimuli, and the overlap between the two activations (yellow). random effects analysis with subjects. display threshold p, . (uncorrected). mni co-ordinates of activation: a: at ( – ). b: at ( – ). and c: at ( – ). the co-ordinates in d are the same as in c. doi: . /journal.pone. .g brain and beauty plos one | www.plosone.org july | volume | issue | e amygdala at – and – ; in visual cortex at - - , corresponding to the right fusiform gyrus; at - - - , corresponding to the left inferior occipital gyrus and in the left superior medial frontal gyrus at - . with the application of a mm svc, left somato-motor cortex at - - and left postcentral gyrus at - - showed significant activation. the former was close to the activation site for ugly stimuli in the study by kawabata and zeki ( ) [ ]. there was no activity at the corrected significance level in the contrast of musically ugly . musically beautiful. the application of a conjunction analysis using the contrast visually ugly . visually beautiful vs. musically ugly . musically beautiful did not give any significant activation. quantitative relationship between experience of ugliness and cortical activation parametric analysis for visual stimuli showed a negative linear relationship between bold signal and declared intensity of experiences at the most significant voxels in left and right amygdala at and and in visual cortex table . activation area in the conjunction analysis. brain regions l/r x y z t ke visually beautiful + musically beautiful . visually ugly + musically ugly medial ofc l . medial ofc l . caudate nucleus l . [visually beautiful . visually ugly] and [musically beautiful . musically ugly] medial ofc (svc) l . table . activations for the contrast visually beautiful + musically beautiful . visually ugly + musically ugly and conjunction analysis for visually and musically beautiful . visually and musically ugly. doi: . /journal.pone. .t figure . modulation of cortical activity by aesthetic rating. averaged parameter estimates showing modulation by beauty rating (beautiful, indifferent and ugly) in mofc for (a) visual stimuli (at – ) and (b) musical stimuli at – . a linear relationship with beauty rating was observed in both conditions. doi: . /journal.pone. .g brain and beauty plos one | www.plosone.org july | volume | issue | e at , corresponding to left inferior occipital cortex. with the application of a mm svc, a similar relationship was also observed in left postcentral gyrus (p, . , corrected) (figure ). a corresponding analysis for musical stimuli did not show any significant activation. discussion activity in mofc during the experience of beauty the mofc is a large expanse of cortex that has several architectonic areas (including brodmann areas , , , and ). it apparently receives few direct sensory inputs but has strong connections with the basal ganglia [ ] and its subdivisions are also heavily interconnected [ ]. the mofc has been activated in many studies probing the relationship of reward, pleasure and judgment [ ], as well as the experience of beauty [ – , ] and value [ ], to cortical activity. given the variety of conditions that have been reported to lead to activation of mofc, our principal interest was to determine whether the same or different subdivisions of this large expanse of cortex are active during the experience of beauty derived from different sources. the approach that we have adopted is similar to the one that we used to determine the cortical activity that correlates with the experience table . activated areas correlating with the experience of ugliness. brain regions l/r x y z t ke visually ugly . visually beautiful amygdala l . amygdala r . fusiform gyrus r . inferior occipital gyrus l . superior medial gyrus l . somato-motor cortex (svc) l . postcentral gyrus (svc) l . musically ugly . musically beautiful no suprathreshold clusters activations for the contrasts visually ugly . visually beautiful, musically ugly . musically beautiful. doi: . /journal.pone. .t figure . cortical activations correlating with the experience of ugliness. statistical parametric maps rendered onto averaged coronal anatomical sections (the average of subjects) showing the t statistic for the contrasts visually ugly . visually beautiful. random effects analysis with subjects: display threshold p, . (uncorrected). (a) coronal planes showing activations in left and right amygdala ( ) and ( ). (b) left somato-motor cortex ( svc). averaged parameter estimates showing modulation by beauty rating (beautiful, indifferent and ugly) in left amygdala and left somato-motor cortex. a linear relationship with beauty rating was observed at each voxel. doi: . /journal.pone. .g brain and beauty plos one | www.plosone.org july | volume | issue | e of temporally asynchronous patterns derived from different sources [ ]. that result showed that each of the sources for temporal asynchrony activates a different zone of frontal cortex, with an additional, common, zone activated by all. in this study, the experience of beauty derived from visual and musical sources correlated with much the same part of the mofc, the overlap between the two being extensive and possibly total. relationship to previous studies many, if not all, studies that have addressed the neural correlates of the experience of beauty have found activity in mofc, although sometimes the region is referred to otherwise. for example, vartanian and goel [ ] refer to their site of activation as being in the anterior cingulate or the sub-genual anterior cingulate although their locus of activation, at , is close to the locus in the study of kawabata and zeki ( ) [ ], that of kirk et al. ( ) [ ] and this one. similarly, tsukiura and cabeza ( ) attribute their locus of activation in response to facial attractiveness and moral goodness to anterior cingulate but the site of activation, at [ ], is very close to the one reported in this study and, in our view, belongs more appropriately to mofc. the activation site reported by di dio et al ( ) in the supplementary material to their study of beauty is in the mofc at ( and ) [ ] as is the activity reported by kranz and ishai ( ) [ ], cloutier et al. ( ) [ ] and o’doherty et al. ( ) [ ] for facial attractiveness. the activations in all these studies fall well within field a of mofc as outlined in the results section. as well, studies of the relationship of value to cortical activity have also implicated the mofc [ ]. even the study of jacobsen et al. ( ), which differed somewhat from the studies mentioned above in that it involved judgments of beauty vs. symmetry, reported activation in the mofc, though at a somewhat more dorsal level (at and ) [ ]. there is one exception to this list which is the result derived from use of magnetoencephalography (meg) (e.g. [ ]). this may possibly have been due to the fact that activity in medially situated cortex is not easily detectable by meg. in sum, a great many results are in agreement that the experience of beauty correlates with activity in mofc. to avoid any ambiguity and to relate the area demarcated here to areas of mofc implicated in other studies, especially those related to judgment, evaluation, reward and desire, we tentatively refer to the area we have described as field a of mofc. it is because of this apparent agreement, that field a of mofc is active in most studies that have explored the relationship between cortical activity and the experience of beauty, that we concentrate on it in this discussion. the extent and boundaries of a must at present be tentative. we place its center at and estimate it to have a diameter of between – mm. there may be further functional subdivisions within it. taking our current results, as well as all the above studies, into account, we conclude (a) that the experience of beauty derived from visual and musical sources correlates with activity in the mofc; (b) that, within the mofc it correlates more specifically with activity in field a ; and (c) that the experience of beauty derived from at least two modalities, visual and musical, shares a common cortical locus in field a of mofc. we therefore modify burke’s definition given above and say that ‘beauty is, for the greater part, some quality in bodies that correlates with activity in the mofc by the intervention of the senses’. field a of mofc, value and judgment the paradigm that we used in this study is, inevitably, both judgmental and evaluative and it therefore makes it interesting to discuss our results in relation to axiology and to previous results that have explored the relationship of value to brain activity. we agree with dw gotshalk [ ] that ‘‘beauty is a value’’, that it commonly evokes desire and that whatever is desired has value, although we tend to place beauty more in the perceiver than in the object, without denying that objects may have characteristics that qualify them as beautiful to one or many subjects. this essentially implies that there must be an intimate link in the cortical processing that is linked to value, desire and beauty. it is therefore interesting to note that the activity in a of mofc that we report here is almost co-terminous with the activity reported in previous studies of the neural correlates of desire [ ] and of value judgments [ ]. this in turn not only reflects what is well known about the relationship of value, judgment, beauty and desire in axiology and philosophical discourse generally but also implies that there might be a value assigning system in the brain that is either supra-modal, that is to say not linked to value within any particular domain, or has specializations within it related to different values (see below). it is interesting to note in this context that the judgments that we speak of above relate to positive judgments, strongly linked to reward and pleasure. we did not find activity in a of mofc that correlates positively with the experience of ugly stimuli, although ugliness, too, involves a judgment. instead, the parametrically modulated activity with the experience of ugliness was confined to the amygdala and left somato-motor cortex. this implies that there may be a functional specialization within the brain for at least two different kinds of judgment, those related to positive, rewarding, experiences and those related to negative ones. future studies may yet reveal further specializations for judgments in different domains. other activations a: visual and auditory cortex. the contrasts visually beautiful . musically beautiful led to widespread activity within visual cortex, while the contrast musically beautiful . visually beautiful led to widespread activity within auditory cortex. that such a large expanse of visual or auditory cortex should have been active is not surprising because the stimuli, whether visual or auditory, had many different characteristics; for example, the visual stimuli consisted of portraits, landscapes, still lifes and were in color while the musical stimuli had different degrees of melody, and harmony, and some were derived from large-scale orchestral performances while others from smaller ones. the activation of these sensory areas in conjunction with activation of mofc is important for the theory we advance below. b: caudate nucleus. one of the more interesting activations was in the caudate nucleus, which was also activated in previous studies charting the neural correlates of emotional states [ , ]. the caudate activations reported here have two features: (a) their location is similar to the location of the activity observed in previous studies of beauty [ ] and in studies of the neural correlates of romantic love [ , , ], and (b) the activation in it is proportional to the intensity of the declared experience of beauty. this close juxtaposition constitutes an interesting neural commentary on the traditional emphasis made in world literature on the relationship between love and beauty. another interesting point about caudate activity is that it is evident only during the experience of visual beauty, with no parallel activation during the experience of musical beauty. we have no current explanation for this. linear relationship between strength of cortical activity and strength of declared experience of beauty confirming previous studies from this and other laboratories [ , , ], the activity in the mofc was parametrically modulated, brain and beauty plos one | www.plosone.org july | volume | issue | e the bold signal being higher for stimuli rated as beautiful than those rated neutral or ugly. this was also true for the caudate nucleus, though only during the experience of visual beauty. a conjunction analysis using results derived from both auditory and visual scans once again showed that the same region (a ) of mofc was parametrically modulated by both visual and musical stimuli, thus adding further to the conclusion that activity in one and the same brain area correlates in the same way with the experience of beauty derived from these two different sources. the experience of visual stimuli as ugly, on the other hand, correlated with activity in the amygdala and (with the application of an svc) in left somato-motor cortex, among other areas (see table ). this activity, too, was proportional to the declared intensity of the experience. when we searched for quadratic modulation, we could not find increased activity in amygdala during the experience of both beauty and ugliness. indeed, we could not detect any areas that had a quadratic relationship with the stimuli (i.e. were active during the experience of beautiful and ugly, but not indifferent, stimuli). in this, our results differ from those of winston et al. ( ) who found that attractive and unattractive faces, but not ones judged to be neutral, lead to amygdala activation [ ]. the reason for this difference is not known. taken together, these results imply that the subjective experience of beauty and of ugliness can be objectively ascertained and measured. toward a brain-based definition of beauty taking the two principal results of this study, namely that activity in a single region (field a ) of mofc correlates with experience of both visual and musical beauty and that there is a linear relationship in it between the bold signal and the declared intensity of the experience of beauty, leads us towards the formulation of a brain based definition of beauty. the question of what beauty is has resisted adequate definition for centuries. some, such as vitruvius, alberti and leonardo da vinci, have sought to understand beauty in terms of the characteristics of the apprehended object. in visual art and architecture this may be reduced to symmetry, proportion, harmony and so on, while in music it may be beat, harmony and rhythm. but what are the characteristics that confer beauty on a more complex scene, such as a theatrical, operatic or cinematic one? and what would the characteristics of moral beauty be? an issue that has much exercised philosophers of art and aesthetics and intrudes into any discussion of beauty is the relationship of beauty to art. while art has been traditionally associated with beauty in the popular mind as well as in past philosophical and artistic speculation, the notion that art and beauty can be equated has of course been questioned in the past and received a fatal blow when marcel duchamp presented his urinal, which he euphemistically named the fountain, to an art exhibition; it then received a further blow with his readymades, which duchamp considered to constitute ‘‘art without an artist’’. notions of art have since changed and many will today acknowledge that something considered to be a work of art need not be perceived as beautiful, good examples being some of the paintings of francis bacon, or the nudes of lucian freud, which is not to say that these works do not have considerable artistic merit both in their painterly style and in projecting truths, including truths about decay and ugliness. but any work, be it considered art or not, may be subjectively experienced as being beautiful by an individual. this leads us to divorce art from beauty in this discussion and concentrate on beauty alone. in our study, we were essentially indifferent to whether a stimulus, be it visual or auditory, constituted a work of art, our only concern being with whether the individual subject, in the scanner, experienced the work as being beautiful or not. in trying to provide an answer, we have been inspired by a critical question asked by the english art historian, clive bell, in his book entitled art [ ], though less so by the answer he gave. bell was concerned in the main with visual beauty but we extend our argument to beauty in general. he wrote, ‘‘if we can discover some quality common and peculiar to all the objects that provoke it [beauty], we shall have solved what i take to be the central problem of aesthetics’’. unlike hume, who placed beauty entirely in the perceiver, bell searched for that ‘‘peculiar quality’’ in the apprehended objects while also giving primacy to the perceiver. he wrote: ‘‘all systems of aesthetics must be based on personal experience–that is to say, they must be subjective’’ [ ]. what quality, he asked, ‘‘is common to sta sophia and the windows at chartres, mexican sculpture, a persian bowl, chinese carpets, giotto’s frescoes at padua and the masterpieces of poussin, piero della francesca, and cézanne?’’, a list that excludes music. we modify his question slightly by adding music and asking: what was common to all the beauty experiences that each of our subjects had when viewing the different visual and musical stimuli? our results inspire us to provide, speculatively and tentatively, and perhaps even provocatively, a new, and neurobiological, answer to bell’s question as modified by us, an answer based exclusively on the perceiver rather than on the object, which is not to say that objects may not have characteristics that qualify them as beautiful. the answer bell gave is that the single characteristic that defines all works of art is ‘‘significant form’’. such a definition has many drawbacks, chief of which is defining what significant form might be in painting, music, fashion, design, film, opera and the many other areas in which we experience beauty, including moral beauty. indeed, bell himself was vague about what ‘‘significant form’’ might be in terms of even elementary visual attributes such as color and line. the term, being resistant to a definition that applies to all areas in which we experience beauty, thus also becomes impossible to measure and quantify. we therefore propose instead a neurobiological definition that makes it un- necessary to define ‘‘significant form’’ or indeed any other characteristic of the work being apprehended, a definition that is amenable to measurement and quantification and which relies on the perceiver alone. we propose that all works that appear beautiful to a subject have a single brain-based characteristic, which is that they have as a correlate of experiencing them a change in strength of activity within the mofc and, more specifically, within field a in it. our proposal shifts the definition of beauty very much in favor of the perceiving subject and away from the characteristics of the apprehended object and gives added strength to the latin proverb that ‘‘de gustibus non est disputandum’’ (in matters of taste there is no dispute). we emphasize again that we do not wish to imply that objects that are classified as beautiful do not have certain characteristics that aid in this classification, although what these characteristics are has been, and continues to be, a subject of debate. our definition thus not only distinguishes sharply between artistic merit and aesthetic value but is also indifferent to what is art and what is not art. almost anything can be considered to be art, but only creations whose experience has, as a correlate, activity in mofc would fall into the classification of beautiful art. that the activity in the mofc is proportional to the intensity of beauty experienced gives added strength to our theory, since the strength of activation is related to the intensity of the experience alone, regardless of the extent to which the work can be classified as a work of art or not. a painting by francis bacon may be executed in a painterly style and have great artistic merit but may brain and beauty plos one | www.plosone.org july | volume | issue | e not qualify as beautiful to a subject, because the experience of viewing it does not correlate with activity in his or her mofc. the definition we propose takes aesthetics very much into the subjective, though quantifiable, arena: it applies only to an individual at a specific time and place since what is judged and experienced as beautiful at one moment and in one context by one subject may not be so experienced by another in a different context. put differently, for an individual who experiences beauty in a francis bacon painting, with a concomitant change in activity within mofc, the work can be qualified as beautiful to that individual. our definition thus makes it un-necessary to consider other factors such as up-bringing, culture, context, connoisseurship and monetary value in the definition of what constitutes the aesthetic appeal of a work of art, although all these factors may contribute to the experience of beauty. indeed, it is for this very reason that we included people from different cultures and ethnic backgrounds in our pool of subjects. there are of course many iconic works of art, such as the music of beethoven or the pietà of michelangelo, which are experienced as beautiful by those who belong to different cultures, backgrounds and ethnic groups. this may be accounted for, as immanuel kant did in his critique of judgment [ ], by supposing the existence of a sensus communis, that is to say a brain organization that is similar across individuals and cultures, which such works stimulate. we are currently addressing this in greater detail. we are of course aware that activity in mofc correlates with the experience of pleasure and reward, whether real or imagined, and its expectation [ – ]. this naturally raises, at a neurobi- ological level, an issue long discussed in the humanities, namely the relationship of aesthetic experience to pleasure (see graham gordon, the philosophy of art [ ]). it can be argued that wagner’s prelude to tristan und isolde is infinitely more subtle and beautiful than a composition by, for example, a rock artist. but this argument has more to do with what is art and what is not art than with what is perceived as beautiful and rewarding and what is not. many who admire and are rewarded by listening to rock music, which they find beautiful, will probably have little time for wagner, and vice versa. we would expect that, in subjects who find rock music rewarding and beautiful, their experience of the beauty of rock music will correlate with activity in their mofc. our definition is concerned with what an individual subject experiences as beautiful at a given moment, nothing else. it is interesting to note that, contrary to the experience of beauty, we could not locate, through our conjunction analyses, a common area in which activity correlated with the experience of musical and visual ugliness, a negative finding for which we have no current explanation. co-activation of mofc and perceptive areas one objection to our hypothesis is that, currently, activity in mofc may be related to other experiences, such as judgment, evaluation, decision-making and reward in other domains, ones that are not directly related exclusively to beauty. for the sake of clarity and because of the complex architectonic configuration of mofc, we designate the area that was active in this study as division a of mofc. activation of mofc in other reward- related tasks, such as monetary reward, involves a different overall pattern of brain activation than the one we report here. moreover, such reward tasks may or may not activate field a of mofc. a recent study [ ] reported overlapping activation with juice and monetary rewards in a region corresponding to a of mofc, although the results of that study, being based on either uncorrected statistics at p, . or corrected statistics at p, . but with the use of an mm svc, are somewhat weak and require further study. this is especially so, since another study based on money rewards puts activity in the orbito-frontal cortex outside a [ ] and at a significantly more anterior position than in the study of kim et al. hence the need for a more precise definition of the relationship of activations derived from different kinds of reward tasks to the extent of field a of mofc. in fact a specialization within mofc may be conferred on it by the cortical route taken to it. in our study, although only activity in one cortical area, a of mofc, correlated with the experience of musical and visual beauty, the path to mofc through the two domains was different. with musical experience of beauty, auditory areas of the brain were co-active with a of mofc while we could not detect any activity in the caudate nucleus. with experience of visual beauty, the caudate nucleus was very much co-active with a of mofc as were the visual areas (we use the term co-active because the temporal limitations of the fmri method do not allow us to isolate the sequence of activity in these areas). hence, basing ourselves more on burke’s definition of beauty given above, as one mediated by the senses, we consider that it is not activation of mofc alone that is a determinant of beauty; it is rather the co-activation of field a of mofc with the specialized sensory and perceptive area, or areas, and possibly (in the case of visual stimuli) with the caudate nucleus as well. hence we broaden our neurobiological definition of beauty given above to include not only activation of mofc but also its co-activation with sensory areas that feed it. the interaction between these sensory areas, and other regions such as the caudate, and a of mofc, and how activity in the latter is modulated by activity in the former remains a very interesting puzzle for the future. we emphasize that our theory is tentative; there are many other experiences that may be deemed to be beautiful besides the visual and musical. our theory will stand or fall depending upon whether future studies of the experience of beauty in other domains show that, in these too, the experience correlates with activity in field a of mofc. supporting information table s behavioral data collected in preliminary behavioral test. distribution of behavioral ratings during preliminary test by stimulus modality, averaged over all subjects. range shows maximum and minimum percentages among subjects. (docx) acknowledgments we thank john romaya for his help at all stages and masamichi hayashi for useful suggestions. we also thank karl friston, ray dolan and anton burdakov for their critical reading of this manuscript. author contributions conceived and designed the experiments: sz ti. performed the experiments: ti. analyzed the data: ti sz. contributed reagents/ materials/analysis tools: sz ti. wrote the paper: sz ti. references . burke e ( ) a philosophical enquiry into the origin of our ideas of the sublime and beautiful. london: r. and j. dodsley. p. . kawabata h, zeki s ( ) neural correlates of beauty. j neurophysiol : – . brain and beauty plos one | www.plosone.org july | volume | issue | e . vartanian o, goel v ( ) neuroanatomical correlates of aesthetic preference for paintings. neuroreport : – . . di dio c, macaluso e, rizzolatti g ( ) the golden beauty: brain response to classical and renaissance sculptures. plos one : e . . blood aj, zatorre rj, bermudez p, evans ac ( ) emotional responses to pleasant and unpleasant music correlate with activity in paralimbic brain regions. nat neurosci : – . . tsukiura t, cabeza r ( ) shared brain activity for aesthetic and moral judgments: implications for the beauty-is-good stereotype. soc cogn affect neurosci. . grabenhorst f, rolls et ( ) value, pleasure and choice in the ventral prefrontal cortex. trends cogn sci : – . . kornysheva k, von cramon dy, jacobsen t, schubotz ri ( ) tuning-in to the beat: aesthetic appreciation of musical rhythms correlates with a premotor activity boost. hum brain mapp : – . . price cj, friston kj ( ) cognitive conjunction: a new approach to brain activation experiments. neuroimage : – . . zeki s, romaya jp ( ) the brain reaction to viewing faces of opposite- and same-sex romantic partners. plos one : e . . bechara a, damasio h, damasio ar ( ) emotion, decision making and the orbitofrontal cortex. cereb cortex : – . . margulies ds, kelly am, uddin lq, biswal bb, castellanos fx, et al. 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architecture of reward value coding in the human orbitofrontal cortex. j neurosci : – . brain and beauty plos one | www.plosone.org july | volume | issue | e doi: . /j.orbis. . . small is beautiful: the counterterrorism option in afghanistan by austin long austin long is an assistant professor at columbia university’s school of international and public affairs. he presented this paper at fpri in december as part of the hertog program on grand strategy, which is jointly sponsored by temple university’s center for the study of force and diplomacy and fpri. abstract: strategy is matching means and ends. if the ends desired in afghani- stan are about al qaeda, the counterterrorism option is the best fit in terms of means. it is sustainable, always crucial in prolonged conflict, as it limits the expenditure of u.s. blood and treasure. this article fills a gap in the existing strategy debate by detailing what a counterterrorism option would be in terms of force structure and operations. o ne of the most important debates to emerge over the future of u.s. strategy in afghanistan is the so-called ‘‘counterterrorism option.’’ this option would shift u.s. strategy and force posture from one focused on a counterinsurgency campaign seeking both to protect the afghan population and build the central state to a narrower effort focused on preventing afghanistan from again becoming a haven for al qaeda. the most prominent proponent of this option (though not the only one) has been vice president joseph biden, who has become deeply pessimistic about the prospect for state-building in afghanistan. in contrast, respected brookings analysts bruce riedel and michael o’hanlon argue that the counterterrorism option is essentially an illusion, doomed to fail if attempted. while this debate was recently resolved in the case of afghanistan by president obama’s decision to pursue a counterinsurgency strategy rather than a counterterrorism one, it still has implications for future u.s. operations. this essay attempts to outline a viable counterterrorism strategy by first defining goals and resources (or ends and means), then describing what peter baker, ‘‘biden no longer a lone voice on afghanistan,’’ new york times, october , . http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan. html. # published by elsevier limited on behalf of foreign policy research institute. spring | http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html the counterterrorism option in afghanistan might have entailed, laying out how the united states might still transition to that posture, and finally specifically addressing the concerns of riedel/o’hanlon and others. if the obama administration adheres to the president’s exit strategy, it may still be necessary to adopt a counterterrorism approach in the future. this article argues that it the united states can still successfully transition to an effective counterterrorism mission over the course of the next three years, ending up with a force of about , military personnel (or less) in afghanistan. the afghan state would likely survive but would lack de facto control over - percent of its territory compared to about - percent today. first, in terms of overall u.s. strategy, as the senior nato and u.s. commander in afghanistan general stanley mcchrystal noted in an october speech, the key to strategy is aligning resources with goals. so, before discussingtheresourcestobeusedinthecounterterrorismoption,goalsmustbe clearly defined. the goal as announced by president obama on march , , is ‘‘to disrupt, dismantle, and defeat al qaeda in pakistan and afghanistan, and to prevent their return to either country in the future.’’ the meaning of defeat, is a bit nebulous-what does it mean to defeat an entity that is both social movement/ ideologyandformalorganization?theothertwogoalsareclearer:disruptmeans to pressure the organization so that it cannot conduct offensive operations against the united states and dismantle means to kill or capture the members of the formal organization along with those that provide it with resources. if that is the u.s. goal, what resources are then needed? according to several assessments, including general mcchrystal’s, substantial numbers of troops will be needed to secure and build a stable afghanistan that will then be inimical to al qaeda and deny it the sanctuary it desires. however, this does not directly disrupt, dismantle, or defeat al qaeda, which primarily now operates next door in pakistan. only if pakistan simultaneously takes action against al qaeda would this approach succeed, essentially squeezing al qaeda into ever narrower spaces along the border, substantially disrupting and dismantling if not totally defeating. however, there appears to be little prospect of pakistan taking these actions in a substantial way. indeed, two of the principal al qaeda allies that the internationalcommunityisfightinginafghanistan,thequettashuratalibanand the haqqani network, receive sanctuary in pakistan and support from pakistan’s inter-services intelligence (isi). those operations against militants that pakistan has undertaken have been directed at the ‘‘pakistani taliban,’’ principally tehrik-e-taliban pakistan (ttp) and tehreek-e-nafaz-e-shariat-e-mohammadi long http://www.latimes.com/news/nationworld/world/la-fg-afghan-mcchrystal - oct , , .story. http://www.whitehouse.gov/issues/foreign-policy. ‘‘comisaf’s initial assessment,’’ august , , pp. - , available online at: http:// www.washingtonpost.com/wp-dyn/content/article/ / / /ar .html. | orbis http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html (tnsm). it is these groups that threaten the pakistani state rather than isi’s afghan proxies. this is not to say pakistan supports al qaeda—indeed pakistan has been helpful in collecting intelligence against some al qaeda targets and has allowed numerous u.s. drone strikes against them. however, in protecting its proxies, pakistan has indirectly protected al qaeda, which shelters in the shadow of afghan as well as pakistani militants. there is no sign that pakistan will cease to provide sanctuary to its proxies and by extension to al qaeda. this means efforts to disrupt, dismantle, and defeat al qaeda in pakistan will continue to be those that have been ongoing—collecting intelli- gence through various means and then targeting with drone strikes based on that intelligence. a stable afghanistan will not change that. moreover, the prospects for a stable afghanistan are grim while afghan militants retain support and sanctuary in pakistan. general mcchrystal’s report acknowledges this: ‘‘while the existence of safe havens in pakistan does not guarantee isaf [international security assistance force] failure, afghanistan does require pakistani cooperation and action against violent militancy, particularly against those groups active in afghanistan.’’ thus, even an increase in u.s. troops and a transformation of counterinsurgency strategy has a high risk of failure if pakistan does not take action against its afghan proxies. again that seems unlikely. moreover, maintaining troops in afghanistan will cost between $ , and $ , , per individual per year, meaning a force of , u.s. troops would cost $ -$ billion per year for an unknown but likely lengthy duration. so the troop increase authorized by the president for afghanistan will not directly disrupt, dismantle, or defeat al qaeda even if executed exactly as general mcchrystal proposes. it will only indirectly be able to do so if pakistan takes action against its afghan proxies, who in turn allow al qaeda to shelter with them, yet there is little prospect of that. finally, the chance of actually succeeding in making afghanistan stable in the first place is low if pakistan does not take action against its afghan proxies. even attempting to stabilize afghanistan as general mcchrystal proposes will be extraordinarily expensive. this seems to pose an insoluble problem for the united states. this insoluble problem is why the counterterrorism option is impor- tant. if even a costly effort in afghanistan cannot fully achieve the goal against counterterrorism option in afghanistan on the different groups, see comisaf’s initial assessment, pp. - ; gilles dorronsoro, ‘‘the taliban’s winning strategy in afghanistan,’’ (washington, d.c.: carnegie endowment for international peace, ), pp. - ; omar waraich and andrew buncombe, ‘‘pakistan readies for new assault on bin laden lair,’’ the independent (uk), october , ; and ‘‘tehrik-e- nefaz-e-shariat-e-mohammadi (tnsm),’’ jane’s world insurgency and terrorism, october, . ‘‘comisaf’s initial assessment,’’ pp. - . christi parsons and julian barnes, ‘‘pricing an afghan troop buildup is no simple calculation,’’ los angeles times, november , . spring | al qaeda, then it is crucial to determine whether a less costly effort can achieve a similar effect by keeping afghanistan inhospitable to al qaeda. this would be a clear and cost-effective alignment of resources with goals, the essence of strategy. determining the viability of the counterterrorism option requires detailing what it might look like. most discussion of the counterterrorism option has been vague. riedel and o’hanlon sum it up as ‘‘a few u.s. special forces teams, modern intelligence fusion centers, cruise-missile-carrying ships and unmanned aerial vehicles. . .’’ but there has been little effort to put flesh on this skeleton in terms of numbers and locations of u.s. troops. the following section presents a possible counterterrorism force posture. possible counterterrorism force posture first,thisposturewouldrequiremaintainingbasesinafghanistan.three airfields (see map below) would be sufficient: bagram (about kilometers north of kabul), jalalabad (in eastern afghanistan) and kandahar (in southern afghanistan). this would enable forces to collect intelligence and rapidly target al qaeda in the pashtun regions where its allies would hold sway. in terms of special operations forces, this posture would rely on two squadrons of so-called ‘‘tier ’’ operators, one at jalabad air field and one at kandahar air field. these would be drawn from classified u.s. special mission units (smus) attached to joint special operations command (jsoc), u.s. army special forces’ combatant commanders in extremis forces (cifs), and allied units such as the british special air service (sas) or canada’s joint task force (jtf ). in addition, the posture would require a battalion equivalent of u.s. army rangers, u.s. navy seals, u.s. marine special operations companies (msocs), british special forces support group, or some mix, with basically a company with each tier squadron or equivalent and one in reserve at bagram. these forces would work together as task forces, with the tier operators being tasked with executing direct action missions to kill or capture long on jsoc and special mission units, see sean naylor, not a good day to die: the untold story of operation anaconda (new york: berkley books, ), pp. - . on army special forces cifs, see fred j. pushies, u.s. army special forces (osceola, wi: zenith press, ), pp. - . on the sas and particularly its counterterrorism capability, see leroy thompson, sas: great britain’s elite special air service (osceola, wi: zenith press, ), pp. - . on jtf , see the official webpage: http://www.jtf .forces.gc.ca/index-eng.asp. special forces’ cifs are not true ‘‘tier ’’ operators but author assesses that they have more than sufficient capability for the role assigned here. on the rangers, see mir bahmanyar, shadow warriors: a history of the u.s. army rangers (new york: osprey publishing, ). on the seals, see dick couch, the warrior elite: the forging of seal class (new york: crown, ). on the msocs, see marine corps official website: http://www.marsoc.usmc.mil/msor.html. on the sfsg, see ministry of defence official website: http://www.mod.uk/defenceinternet/factsheets/defenceinwales.htm. | orbis http://www.mod.uk/defenceinternet/factsheets/defenceinwales.htm http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html al qaeda targets while the other units would serve as security and support for these missions. according to sean naylor’s reporting, these direct action task forces are structured like the regional task forces in iraq in that were tasked to hunt al qaeda in iraq. naylor also reports similar units are already in place in afghanistan. in addition to these ground forces, a battalion task force from the th special operations aviation regiment (soar) would be used to provide helicopter transport, reconnaissance, and fire support for the task forces. counterterrorism option in afghanistan sean naylor, ‘‘spec ops unit nearly nabs zarqawi,’’ army times, april , and sean naylor, ‘‘special ops ‘surge’ sparks debate,’’ army times, december , . spring | the battalion would bring some mix of mh- heavy lift helicopters and mh- medium lift helicopters, including the mh- l gunship. the helicopters have a combat radius of at least kilometers (km), giving the task forces operational reach to almost any part of the pashtun region. this battalion could be supplemented with additional aviation assets from other units, such as cv- tilt rotor aircraft from the air force’s th special operations squadron or ah- attack helicopters from any one of several army aviation units. the jaf based task force would likely need to operate principally in the heartland of the haqqani network (khost, paktia, and paktika provinces) as this would be where al qaeda’s principal ally in the east could best protect its members (who are not generally pashtun). for similar reasons, the kaf based task force would principally operate against targets in kandahar, the home of the quetta shura taliban, and some of the surrounding provinces such as helmand and oruzgan. both task forces would nonetheless be capable of acting against targets elsewhere in the pashtun regions. in addition to these two task forces, a counterterrorism option would retain the three army special forces battalions and other elements that appear to be assigned to combined joint special operations task force- afghanistan (cjsotf-a). this provides roughly special forces opera- tional detachment alphas (odas), the basic unit of army special forces. while the task forces would focus purely on direct action, odas would partner with local forces to collect intelligence and secure specific areas. additionally, these odas would provide crucial support to critical afghan allies and reassure them that the united states is not going to entirely abandon them. cjsotf-a should, in addition, have a dedicated helicopter battalion for its own lift. this reassurance and support of local allies is a crucial and under- appreciated part of a counterterrorism option, though such support to local allies could also be part of a counterinsurgency campaign. indeed, the recently launched community defense initiative (cdi) seeks to use special forces troops to build effective tribal militias to fight the taliban and other militants. long fred j. pushies, night stalkers: th special ops aviation regiment (osceola, wi: zenith press, ). see entry in jane’s all the world’s aircraft database. both have a greater combat radius under normal conditions but the thin and often hot air in afghanistan will reduce the radius substantially. see th special operations squadron factsheet, online at: http://www .hurlburt.af.mil/ library/factsheets/factsheet.asp?id= . naylor, ‘‘special ops ‘surge’ sparks debate.’’ on oda partnering with a variety of local forces, see linda robinson, masters of chaos: the secret history of the special forces (new york: publicaffairs publishing, ). jon boone, ‘‘u.s. pours millions into anti-taliban militias in afghanistan,’’ guardian, november , . see also special forces officer jim gant’s paper ‘‘one tribe at a time,’’ online at: http://blog.stevenpressfield.com/wp-content/themes/stevenpressfield/one_tribe_ at_a_time.pdf. | orbis http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html with odas, the united states could potentially support local allies in roughly afghan districts, assuming one oda per district with a few deployed in other roles. logistics might prevent this upper limit from being reached but at a minimum several dozen districts could be supported by cjsotf-a’s odas. these local allies would in many cases be from non-pashtun groups (tajiks, uzbeks, hazaras), which would limit their ability to be effective in pashtun areas but would likely include at least a few other tribes that see more benefit working with the afghan government and the united states than against them. the non-pashtun groups were the critical allies of the united states in and remain staunchly against the taliban and other militants. the tajiks of the panjshir valley, for example, are probably even more anti-taliban than the united states and have made the province one of the most secure in the country. with u.s. support, these groups will be able to prevent the expansion of militants outside pashtun areas. local allies in pashtun areas will not only help contain militants but will also enable collection of intelligence to support the task force operations. one example is the shinwari tribe in nangarhar province, which has never valued the taliban. shinwari militias are reported to be working with special forces in the achin district of nangarhar. the afghan border police commander on the afghanistan-pakistan border at spin boldak, general abdul razziq, also derives substantial revenue from cross-border trade and will likely continue to fight the taliban to maintain this revenue, making him a probable local partner. another potential ally is the alokozai tribe in the arghandab district of kandahar province, which has a history of resisting the taliban. supporting local allies does not mean abandoning the afghan govern- ment any more than supporting local allies in the awakening movement in iraq’s anbar province meant abandoning the iraq government. however, it does pose risks, as local allies interests may not always align with those of the counterterrorism option in afghanistan one oda per district seems reasonable based on jim gant’s description of oda ’s experience in kunar province’s district of khas kunar. see gant, pp. - . ben arnoldy, ‘‘after afghanistan election, governors seek distance from ‘illegal’ karzai,’’ christian science monitor, november , and author observations in panjshir, july . dexter filkins, ‘‘afghan militias battle taliban with aid of u.s.,’’ new york times, november , . sean m. maloney, ‘‘a violent impediment: the evolution of insurgent operations in kandahar province - ,’’ small wars & insurgencies v. n. (june ), pp. - ; carlotta gall, ‘‘taliban rebels still menacing afghan south,’’ new york times, march , ; ‘‘suicide bombers strike kandahar police hq,’’ associated press, september , ; and author interviews, kandahar, july . sarah chayes, ‘‘a mullah dies, and war comes knocking,’’ washington post, november , and m. karim faiez and laura king, ‘‘anti-taliban leader was target of deadly bombing, officials say,’’ los angeles times, february , . the resistance of the alokozai declined when two key leaders died in - but could potentially be revived. spring | central government. balancing the two will require deftness which will be discussed later. in addition to the two task forces and cjsotf-a, a few more ‘‘enablers’’ would be required. first, this posture would need additional special opera- tions personnel focused on intelligence collection, along with a substantial complement of intelligence community personnel to collect both human and signals intelligence. second, it would require a significant complement of unmanned aerial vehicles (uavs) including predators, reapers, and other specialized types along with their support personnel, equivalent to perhaps three squadrons. third, an ac- gunship squadron for air support would be needed, along with combat search and rescue teams from air force special operations command. clearly, ‘‘small’’ is a relative term. this special operations posture alone would be roughly five battalions of ground forces, eight aviation squadrons/ battalions, and a few odds and ends plus higher headquarters. this would be approximately , u.s. and coalition troops. in addition, a conventional force component would be needed to serve as a quick reaction force, to provide security for the bases, and to protect convoys. a reasonable estimate for this force would be a brigade or regimental combat team, giving a battalion to each base with the higher headquarters at bagram. this would add about another , troops. in addition, about u.s. personnel would remain as advisers and liaisons to afghan security forces, particularly the afghan national army where they would be attached at brigade and corps level. additional air support besides the uavs and ac- s would also be needed. two squadrons of fighter-bombers (f- e, a- , etc.) likely would be long on iraq, see austin long, ‘‘the anbar awakening," survival v. n. (march/april ); steven simon, ‘‘the price of the surge,’’ foreign affairs, v. n. (may/june ); and john a. mccary, ‘‘the anbar awakening: an alliance of incentives,’’ the washington quarterly, january . for discussion of these units and what they might look like, see naylor, not a good day to die and michael smith, killer elite: the inside story of america’s most secret special operations team (london: weidenfeld & nicholson, ). each special forces battalion is roughly personnel, while a ranger battalion is roughly personnel and two squadrons of tier operators would hypothetically be about personnel total (including some support personnel). a helicopter battalion is roughly personnel and each uav squadron has roughly personnel in theater (or less depending on the system). an ac- squadron is roughly personnel. see the relevant tables of organization and equipment (to&e) for each unit. this totals about , personnel, with an additional for intelligence collection and analysis along with higher headquarters functions. this is the approximate number of personnel for an army stryker brigade combat team, see field manual - . the stryker brigade combat team, pp. - . | orbis sufficient, adding another , personnel or so. finally, this posture would require additional staff, logistics, and support personnel (medical for instance), some but not all of which could be contractors, adding another , military personnel. this would be a total force of about , military personnel and some supporting intelligence community personnel and con- tractors. this is a high-end estimate and the counterterrorism option could potentially be done with fewer troops. some military personnel with afghani- stan experience believe this mission could be undertaken with half this number of troops but the posture described above errs on the side of caution. this is small compared to the current posture in afghanistan, smaller still than the forces implied in general mcchrystal’s report, and tiny compared to the peak number of forces in iraq. on the other hand, it is vastly larger than any other counterterrorism deployment. holding aside for a moment whether this is a sufficient force to prevent al qaeda’s return to afghanistan, how would the united states get to this posture? it would not do so overnight and the way it transitions will have consequences. first, the obama administration should embrace the expansion of afghan security forces, especially the afghan national army (ana), called for in general mcchrystal’s initial assessment. this includes accelerating the growth of the ana to , by october from its august level of , as well as pushing to rapidly expand the afghan national police (anp). though the quality of afghan forces will likely be low and the goals may not be met, some increase in total force levels should be possible and will enable the u.s. transition to a counterterrorism posture. second, the president has directed an increase in force levels begin- ning this year. a counterterrorism strategy would have these additional forces concentrate on achieving the expansion of the afghan security forces that gen. mcchrystal has called for. will be a time of feverish arming and training of afghan forces while coalition forces hold the line. president obama has already directed that beginning in early , the united states will begin to draw down its conventional forces as afghan forces stand up. by the time of counterterrorism option in afghanistan each squadron would itself have only about - personnel but would require significant numbers of support personnel. for example, the three fighter squadrons of the th fighter wing have only about personnel but the wing itself has about , personnel for maintenance, logistics, and airfield operations. the analysis here assumes that it will require about half that number in theater to maintain two squadrons. see th fighter wing factsheet at: http://www.mountainhome.af.mil/library/factsheets/factsheet.asp?id= . this is slightly more than an old division support command (discom) for a light infantry division (about personnel) for a somewhat smaller force. see toe associated with field manual - - division support command light infantry, airborne, and air assault divisions. author personal communication, september . comisaf initial assessment, pp. g- to g- . for pessimistic assessments about expansion, thom shanker and john cushman, ‘‘reviews raise doubts on training of afghan forces,’’ new york times, november , . spring | http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html the presidential election or soon thereafter, the united states would shift fully to the posture described above (essentially a - month drawdown). the strategic goal of this transition is to ensure the survival of an afghan state while acknowledging that probably - percent of the country (i.e. almost all of the pashtun regions) will be under the de facto control of militants. at present, militants control, by fairly pessimistic estimates, perhaps - percent of the country (though they are able to conduct attacks in a larger area than that). rather than seeking to reverse this control, the counterterrorism option seeks to contain it. this will limit al qaeda’s potential haven and ensure that the united states has continued access to the bases it needs through reassurances to the government and local allies. there are a few critical regions that will have to be defended, but this should not be too arduous. the first is kabul and its surrounding area, for both symbolic reasons and to ensure the viability of bagram airbase. the second is jalalabad and the surrounding area, along with the road links east to the kyber pass and west to kabul. the third is kandahar city and the surrounding area, along with the road link to kabul. this is a total of about kilometers of highway along with the three cities. the kilometers could probably be guarded reasonably effectively by about ten ana kandaks (battalions) a total of about , personnel (less than percent of the force goal for late ). this would yield one kandak for every seventy five kilometers. these forces could be replaced or supplemen- ted by anp along with local defense organizations such as afghan public protection program (ap ) or cdi. similarly each of the three cities could be allocated ten kandaks to secure it. this total of forty kandaks is less than the number deemed combat ready in (forty six according to the afghan ministry of defense). consequently, there should be plenty of afghan security forces to accomplish this mission even if the expansion of security forces in - is not very successful. these forces would retain the ability to call long this is derived from a count of the districts in provinces with substantial insurgent presence, based on figures in the june department of defense report progress towards security and stability in afghanistan, p. ; dorronsoro, ‘‘the taliban’s winning strategy,’’ pp. - ; and author’s observations and interviews in afghanistan in july . this gives militants credit for controlling most ( - %) of the districts in helmand, kandahar, paktia, paktika, khost, kunar, nuristan, and zabul along with some ( - %) of the districts in ghazni, oruzgan, farah, laghman, wardak, and logar. in addition, insurgents control a few districts in nangarhar and kunduz. this gives a range of districts controlled by insurgents from about to out of ( - %) and probably overstates the extent of insurgent control. if the militants controlled all the districts in the provinces listed above (except nangarhar and the hazara districts of ghazni, oruzgan, and wardak), which would represent virtually all the pashtun districts, this would give them about - districts ( - %). however, nuristan and kunar ( districts, about % of the total) are dominated by the hezb-i-islami gulbuddin (hig), which is separate from the quetta shura taliban and haqqani network and not strongly affiliated with al qaeda. http://www.mod.gov.af/. | orbis http://blogs.usatoday.com/oped/ / /column-why-we-cant-go-small-in-afghanistan.html on u.s. air support if needed through the brigade level u.s. advisers and in extremis could be supported by the u.s. conventional forces stationed at the three air bases, giving high confidence that they can hold these cities. both the central government and local allies will also continue to benefit from u.s. aid, greatly reducing their incentive to turn on the united states. the united states, via the central intelligence agency (cia) and special operations forces, very effectively paid off various groups when it toppled the taliban in - . according to one report, the united states continues to pay the brother of president hamid karzai for his support, including providing individuals to serve in a paramilitary force. if the largesse continues to flow, there seems little reason to believe support for the united states will not continue among the beneficiaries (i.e. key elites and their followers). during this transition, the united states will have to continue support- ing the central government even as it builds up local allies. this balancing act is required to ensure the continued existence of a formal, if weak, central state, which will in turn simplify the negotiations for the u.s. counterterrorism posture. tying the local allies to the central state in some way would help with this and an expanded cdi or the similar afghan public protection program provides a means to do this. some might argue that this increases the risk of warlordism, which may or may not be true but is also irrelevant to the strategic goal of disrupting, dismantling, and defeating al qaeda. the transition will also mitigate the moral hazard endemic to support to counterinsurgency. put simply, the united states and its allies are more committed to a stable, democratic afghanistan than the afghan government. the mcchrystal report rightly notes the massive problems with corruption and poor governance in afghanistan that hobble the counterinsurgency effort. yet as long as the united states and its allies are willing to pour ever more counterterrorism option in afghanistan on this period and pay-offs, see gary schroen, first in: an insider’s account of how the cia spearheaded the war on terror in afghanistan (new york: ballantine books, ); gary berntsen and ralph pezzullo, jawbreaker: the attack on bin laden and al qaeda (new york: crown publishers, ); dalton fury, kill bin laden: a delta force commander’s account of the hunt for the world’s most dangerous man (new york: st. martin’s press, ); and henry a. crumpton, ‘‘intelligence and war: afghanistan - ,’’ in jennifer e. sims and burton gerber, eds., transforming u.s. intelligence (washington, d.c.: georgetown university press, ). dexter filkins, mark mazetti, and james risen, ‘‘brother of afghan leader said to be paid by c.i.a.,’’ new york times, october , . the apparent difference in cdi and ap is the level of training and vetting of personnel, which is apparently higher in ap . the trade-off is that ap takes longer to put in place. see boone, ‘‘u.s. pours millions. . .’’ and farah stockman, ‘‘shifting afghan loyalties test u.s. bid for permanent gains,’’ boston globe, july , . for a critique of the use of tribal forces, see kim marten, ‘‘the danger of tribal militias in afghanistan,’’ journal of international affairs, v. n. (fall/winter ). ‘‘comisaf initial assessment,’’ pp. - to - . spring | troops into the country, it has little leverage over the government. in this circumstance, the threat to cut support, which secretary of defense robert gates has suggested, is not terribly credible. with a transition to a small footprint and the development of local allies, a clearer signal will be sent that the afghan government has to do more. clearly the transition will not solve this problem, but it will at least be a step in the right direction. it will therefore take about three years to get to this posture. but will it work? first, this is clearly not the u.s. posture before september , , so any comparisons tothat period are inapt. second, arguments that this was essentially the united states posture from - are much closer to the mark. however, here the argument is that this posture ‘‘failed’’ because the militants have made a comeback. yet this misinterprets the strategic goal completely. if the strategic goal is a stable afghanistan, then the strategy was a failure. if the strategic goal is to disrupt, dismantle, and defeat al qaeda in afghanistan, it was a success: there are, at present, few al qaeda members in afghanistan and certainly no senior leadership. in an interview on october , national security adviser james jones noted of al qaeda in afghanistan that the ‘‘maximum estimate is less than operating in the country, no bases, no abilitytolaunch attackson eitherus or our allies.’’ the counterterrorism option merely seeks to ensure that this minimal level of al qaeda presence continues in the future. alternately, this argument conflates all militants under the rubric al qaeda. this is problematic: if any thug with a kalashnikov is a threat to u.s. national security then readers should prepare for a rough future as there are millions of them spread across the globe. it is this conflating of the local fighter with the global terrorist that david kilcullen’s accidental guerilla rails against, so it would behoove the united states to avoid this error. more generally, riedel and o’hanlon claim this small footprint posture will be ineffective because actionable intelligence will not be obtained without a substantial conventional force ground presence. yet this is belied by the fact that the united states gains actionable intelligence against targets in even very dangerous areas in which it has essentially no ground forces. in somalia in , a small u.s. task force, supported by a small conventional force, was able to collect intelligence on the habr gidr clan. cia and special operations long for a lucid discussion of the problem of leverage in counterinsurgency, see ben schwarz, american counterinsurgency doctrine and el salvador: the frustrations of reform and the illusions of nation building (santa monica, ca: rand, ). elisabeth bumiller, ‘‘gates says u.s. could withhold aid if afghanistan cannot curb corruption,’’ new york times, november , . ‘‘adviser downplays threat of renewed al-qaida haven,’’ associated press report, october , . david kilcullen, the accidental guerilla: fighting small wars in the midst of a big one (oxford: oxford university press, ). linda robinson, masters of chaos: the secret history of the special forces (new york: publicaffairs publishing, ) and mark bowden, black hawk down: a story of modern war (new york: atlantic monthly press, ). | orbis personnel were also able to collect intelligence in iraq before the invasion. the united states also has a good track record of gaining actionable intelligence specifically against al qaeda in hostile environments without conventional forces. at least three times in - , the united states collected sufficient intelligence to enable strikes on al qaeda affiliates in somalia, where there are no conventional u.s. forces. a similar strike was launched in yemen in , another country lacking u.s. conventional forces. across the border from afghanistan in pakistan it has struck even more targets (according to one source at least thirty eight from september to march ) despite having no conventional presence. some will protest that the pakistanis serve as the ground presence in pakistan, but they do not have a substantial security force (or in some cases any at all) presence in many areas where the united states has targeted al qaeda. for example, in the militant redoubt of south waziristan, where the united states has launched multiple drone strikes, pakistan had no sig- nificant conventional ground force presence until october . others argue somalia and yemen are poor comparisons because they are mostly flat and on the coast, making offshore intelligence collection easy. while true, this argument stresses access, not ground force presence, which enables collection. yet with the posture recommended in this article, the united states is assured vastly greater access than it has in either somalia or yemen. in the period immediately after september , , even with essen- tially no conventional ground presence in afghanistan, small teams of u.s. intelligence and special operations forces worked with local allies to gain substantial intelligence on al qaeda in an environment filled with hostile taliban. a poorly executed operation at tora bora enabled osama bin laden to escape, but this was not because intelligence was unavailable. even this failure resulted in the deaths of many al qaeda associates and forced its counterterrorism option in afghanistan michael tucker and charles faddis, operation hotel california: the clandestine war inside iraq (guilford, ct: the lyons press, ) and robinson, masters of chaos. karen deyoung, ‘‘u.s. strike in somalia targets al-qaeda figure,’’ washington post, january , ; eric schmitt and jeffrey gettleman, ‘‘qaeda leader reported killed in somalia,’’ new york times, may , ; and ian black, ‘‘somalia raid: warning that u.s. can strike at will,’’ guardian, september , . tony karon, ‘‘yemen strike opens new chapter in war on terror,’’ time, november , . greg miller, ‘‘predator strikes in pakistan: u.s. says drones ravage al qaeda,’’ chicago tribune, march , ; salman masood, ‘‘taliban in pakistan confirm that their leader is dead,’’ new york times, august , ; and tim reid, ‘‘former cia agent’s hunt for bin laden in pakistani badlands,’’ times (uk), september , . zahid hussain and matthew rosenberg, ‘‘pakistan begins offensive against taliban,’’ wall street journal, october , . spring | leadership to flee the country. it seems implausible that a vastly more robust presence in afghanistan would be significantly less capable of collecting intelligence than these small teams, or similar u.s. efforts in somalia and pakistan. at best, large numbers of u.s. troops make the work of intelligence collectors easier. their presence helps prevent militants from massing forces to attack small units and provides readily available quick reaction forces, allow- ing collectors to assume more risk in collection. conventional forces also collect some intelligence organically via patrols and engagements. with a reduced force posture, collectors will have to be more circumspect and work harder. yet as the above examples of collection in hostile environment demonstrate, this will not prevent them from operating. another argument against the small footprint is that u.s. ground forces in substantial numbers in afghanistan have given the united states more leverage over pakistan. according to this explanation, the increase in troops in afghanistan provides the rationale for pakistani offensive operations against militants in and also why u.s. drone targeting has been more successful in the same period. yet the timing suggests that this change in behavior has more to do with pakistani perceptions of the militants’ threat. pakistani operations began when in april militants broke a ceasefire that was only a few weeks old and sought to expand their control towards the punjabi heartland of pakistan. this timing seems significant in explaining pakistan’s offensives. in contrast, u.s. drone strikes increased in tempo beginning in late , months before a decision to send more troops to afghanistan was made. even if troops do give leverage over pakistan, how much is that leverage worth in u.s. blood and treasure? there is no sign that additional troops will cause pakistan to stop supporting its proxies. in terms of the strategic goal of disrupting, dismantling, and defeating al qaeda, pakistan was aiding u.s. intelligence collection and began allowing drone strikes in june when there were less than , u.s. troops in afghanistan. thus, it seems likely they will not simply stop it with , there. the final argument marshaled against this small footprint posture is that it hands al qaeda a major propaganda victory. it could claim it drove another superpower out, that the west lacks will, and the like. there is some merit in this argument but with , u.s. military personnel in the country long in addition to the sources in fn , see naylor, not a good day to die and peter krause, ‘‘the last good chance: a reassessment of u.s. operations at tora bora,’’ security studies, october . see ‘‘taliban deceived govt., staged withdrawal drama,’’ daily times (pakistan), april , . see miller, ‘‘predator strikes in pakistan.’’ see lisa burgess, ‘‘u.s. troop presence in afghanistan at , , and expected to hold steady,’’ stars and stripes, july , and ismail khan and dilawar khan wazir, ‘‘night raid kills nek, four other militants,’’ dawn, june , . | orbis hunting for al qaeda day and night, it would probably not prove to be a resounding victory. more importantly, it is far from clear what this propaganda victory would mean in terms of the strategic goal. it would not appear to have much effect on the first two goals, as al qaeda would continue to be disrupted and dismantled by operations in pakistan and afghanistan, the latter of which will remain highly unsafe for al qaeda. it might make it harder to achieve the third goal, defeat. yet it is this goal that is most unclear anyway. in fact, thomas rid and marc hecker argue in war . that, while it has become impossible for al qaeda to ‘‘win’’ in any meaningful sense, its existence as a transnational social movement using various media means it cannot be totally defeated either. finally, the united states has to leave afghanistan at some point, so it is inevitable that it will make the claim to have driven the united states out. as policymakers have sought to grapple with the challenge of afgha- nistan, the lessons of vietnam have been invoked and debated by both those favoring an increase in u.s. troops and those against it. yet vietnam was not the united states only experience with irregular warfare in southeast asia. the u.s. experience in laos provides a better historical analogy for u.s. strategic ends and means in afghanistan. in laos, the united states supported both a weak central state and minority tribes, principally the mountain dwelling hmong. the u.s. goal was limited, seeking both to interdict the use of laotian territory to supply communist forces in south vietnam and to tie down as many north vietna- mese units as possible. beginning in and with only a handful of cia case officers, development workers, and special forces personnel, the u.s. mission worked with hmong leader vang pao to create an effective guerilla force. this force had notable successes against the communists, evolving into a force capable of holding territory when supported by u.s. airpower and small numbers of thai ground forces. other cia-supported irregular units and even a few laotian government units were also effective. in addition, the strategy was able to tie down multiple north vietnamese divisions and ensure that the laotian government held about as much territory in as it did in . as with laos, u.s. goals in afghanistan are strictly limited and do not require a major state building enterprise. if anything, u.s. goals in afghanistan counterterrorism option in afghanistan thomas rid and marc hecker, war . : irregular warfare in the information age (santa barbara, ca: praeger, ). see for example lewis sorley, ‘‘the vietnam war we ignore,’’ and gordon goldstein, ‘‘from defeat, lessons in victory,’’ contrasting op-eds in the october , new york times. see thomas ahern, undercover armies: cia and surrogate warfare in laos, - (washington, d.c.: center for the study of intelligence, -declassified ); douglas blaufarb, organizing and managing unconventional war in laos, - (santa monica, ca: rand, -declassified ); roger warner, shooting at the moon: the story of america’s clandestine war in laos (south royalton, vt: steerforth press, ); and kenneth conboy and james morrison, shadow war: the cia’s secret war in laos (boulder, co: paladin press, ). spring | are more limited than in laos, as the goal in the former is to keep out at a few hundred irregular fighters while the latter sought to oppose tens of thousands of disciplined soldiers. the limited goals in laos could be achieved with limited means, making it sustainable for more than a decade. a similar limited means strategy will likewise make u.s. strategy in afghanistan sustainable for the long term. to return to the point from which this analysis began—strategy is matching means and ends. if the ends desired are about al qaeda, the counter- terrorism option is the best fit in terms of means. it is sustainable, always crucial in prolonged conflict, as it limits the expenditure of u.s. blood and treasure. it is also less dependent on pakistan choosing to abandon its proxies, a possibility that seems remote at present. the counterterrorism option is not only possible, but as steve simon and jonathan stevenson argue, it is the best alternative for the united states. long steven simon and jonathan stevenson, ‘‘afghanistan: how much is enough?’’ survival, october . | orbis small is beautiful: the counterterrorism option in afghanistan possible counterterrorism force posture the beautiful game? hegemonic masculinity, women and football in brazil and argentina this is a repository copy of the beautiful game? hegemonic masculinity, women and football in brazil and argentina. white rose research online url for this paper: http://eprints.whiterose.ac.uk/ / version: published version article: wood, d. ( ) the beautiful game? hegemonic masculinity, women and football in brazil and argentina. bulletin of latin american research, ( ). pp. - . issn - https://doi.org/ . /blar. eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ reuse this article is distributed under the terms of the creative commons attribution (cc by) licence. this licence allows you to distribute, remix, tweak, and build upon the work, even commercially, as long as you credit the authors for the original work. more information and the full terms of the licence here: https://creativecommons.org/licenses/ takedown if you consider content in white rose research online to be in breach of uk law, please notify us by emailing eprints@whiterose.ac.uk including the url of the record and the reason for the withdrawal request. mailto:eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ bulletin of latin american research, vol. , no. , pp. – , the beautiful game? hegemonic masculinity, women and football in brazil and argentina david wood university of shefield, uk the practice of football by women in latin america is an integral part of historical patterns around the performance of gender roles and offers insights into how power, both symbolic and political, is subject to ongoing processes of negotiation. a study of women’s involvement as spectators and players in brazil and argentina since the early twentieth century sees football emerge as a ield in which the construction of gender identities, both personal and national, may be contested. more recently, a growing presence of female players, writers and academics suggests that female agency through football in latin america is an increasingly realistic goal. keywords: argentina, brazil, football, latin america, marta, women. taking the field football in latin america has become irmly established as a subject of study for historians, sociologists, anthropologists and literary scholars, especially in relation to argentina and brazil, but the great majority of publications arising from such work focus entirely on the game as played by men. indeed, some inluential authors have depicted football in the region as an entirely male affair: argentinian anthropologist eduardo archetti, for example, wrote in that football was and still is a typical and exclusively masculine sport in argentina (archetti, : ), reiterating almost a decade later that the world of football is exclusively male, an encounter in the stadium [ … ] between competing groups of male players and supporters (archetti, : ). as will be seen, women have played football in argentina and elsewhere in the region since the s and have been a prominent feature of latin american football crowds from the start of the twentieth century; archetti’s apparent gender blindness is striking in an author who devoted much of his research to the exploration of masculinities. sports historian joseph arbena was among the irst to note the under-representation of women’s football (and of women’s sport more widely) in latin america (arbena, , ), and this lacuna has been addressed to some extent since the turn of the millennium through a recognition of women’s place in football as part of national or regional studies (binello etal., ; santillán, ; elsey, ; goldblatt, ; nadel, ; bocketti, ). an integral part of this process has been the rise in © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. this is an open access article under the terms of the creative commons attribution license, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. david wood women – especially latin american women – writing about women and football in the region (binello etal., ; goellner, , ; mourão and morel, ; votre and mourão, ; rodríguez, , ; da costa, ; santillán, ). both as a practice and as a discourse, football in latin america has constituted an important mode of hegemonic masculinity, understood as the pattern of practice (i.e., things done, not just a set of role expectations or an identity) that allowed men’s dom- inance over women to continue (connell and messerschmidt, : ). football’s status as the most popular sport in almost every country of latin america, and its close association with concepts of a nationhood that is markedly gendered in much of the region, has resulted in its domination of print and electronic media over the course of the last hundred years. what french anthropologist christian bromberger termed the footballisation of society (losson and villepreux, ) has been evident across most of latin america from at least the s, which witnessed the colossal growth in the weight of sport as a media product (alabarces, : ). the role of the media as one of the prime sites for the reproduction of gender divisions (har- greaves, : ) has long been noted, and media coverage of sports events has given rise to a growing number of studies around gender issues. in keeping with the notion that media representations of sport constitute a site where meanings around gen- der are continually contested, not ixed (brookes, : ), this study will explore the ways in which women in brazil and argentina have been represented – and have represented themselves – through football. on examining the practice of football and its representation as a discourse in a range of texts in the printed media, it is appar- ent that brazilian and argentinian women have created a space within football culture by engaging with it and contributing to it in various ways. their participation in the sport has contested hegemonic masculinity and its counterpart emphasised feminin- ity, which is deined around compliance [with the subordination of women to men] and is oriented to accommodating the interests and desires of men (connell, : ). the complex relationships that have arisen from these interactions offer new understandings of the place of women in relation to football and to the public domain more widely. women’s football in latin america has undergone signiicant change over recent decades, with the establishment of national teams across the region by the end of the s and seven editions of the copa américa femenina since the tournament was irst held in brazil in . at the same time, women’s leagues were founded in various latin american countries around the turn of the millennium, giving rise to the copa liber- tadores femenina since . as the country in which football has perhaps been most closely allied to a sense of nation, brazil has been the dominant force, winning the copa américa six times (they inished second to argentina in ) and with brazilian club teams winning each edition of the copa libertadores, with the exception of the inal, in which the chilean side colo-colo defeated brazil’s foz cataratas on penalties. the brazilian seleção is the only national team from the region to reach the latter stages of the fifa women’s world cup (third place in and runner-up in ) or the olympic games (silver medal in and , fourth place in rio ), although colombia, costa rica, ecuador and mexico have performed increasingly strongly in international competition over the last decade. against such a background, brazil and argentina will constitute the primary focus of this study. the manner in which foot- ball has acquired a high degree of cultural capital in these nations in particular, thereby occupying a central place in the exploration of modern nationhood, makes the recent prominence of women in football all the more signiicant and challenging. © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. the beautiful game? early representations of women and football evidence for the participation of latin american women as football players prior to is scant. among the earliest documentary evidence of women’s football in the region is a record of an inter-district match in são paulo in ‘entre senhoritas "tremembenses" contra senhoritas “cantareinenses”’ (between young ladies from tremembé and santa catarina) (goellner, : ), while rio de janeiro’s jornal dos sports carried reports of at least two matches between teams made up entirely of women during may (mourão and morel, : – ). the irst of these refers to ‘gentis senhoritas’ (nice young ladies) ( may ), while the second mocks the manner in which ‘a partida estava sendo disputada com enthusiasmo. as pequenas empregaram-se com extraordinário ardor. de vez em quando, uma acertava a bola ou esta batia nellas’ (the match was being contested with great enthusiasm. the little dears engaged with extraordinary passion. from time to time one of them managed to kick the ball or it bashed into them) ( may ). in argentina, the popular sports magazine el gráico published photographs of women playing football on january and in poet bernardo canal feijóo provided the earliest literary depiction of an organised match between women’s teams in his collection of poems entitled penúltimo poema del fútbol. of poetic vignettes that portray a single matchday, ‘fútbol de mujeres’ (women’s football) is the penultimate entry, followed only by the epilogue. by opening with ‘no podía prosperar el partido’ (the match could not prosper) (canal feijóo, [ ] : ), the author makes clear his opposition to the women’s involvement and later unwit- tingly makes explicit the framework of normative masculinity (and expected female heterosexuality) within which he is working, describing how ‘los choques trababan a las jugadoras en un abrazo lésbico inaceptable’ (the tackles entangled the players in an unacceptable lesbian embrace) (canal feijóo, [ ] : ). such depictions suggest that women’s participation in the sport had still to become separated from traditional visions of female roles and that the presence of women on the pitch was seen as an entertaining – or occasionally threatening – anomaly by the male writers of such reports, who gave early expression to hegemonic masculinity through football. there are, of course, other ways in which women were involved in football from the early twentieth century, and there is ample evidence of their enthusiastic presence in the crowd at important games (bocketti, : – ). a newspaper report from october spoke of how prominent were the elegant women who lent a happy note to the festivities at the irst match between representative teams from são paulo and rio de janeiro (cited in goldblatt, : ), while joão do rio described how ‘moças de vestidos claros perfumam o ambiente com o seu encanto’ (women in pale dresses perfume the atmosphere with their charm) in his report for rio de janeiro’s gazeta de noticias on a matchday visit to fluminense ( : ). in the country’s other major city, são paulo-based modernist author alcântara machado published in the short story ‘corinthians ( ) vs palestra ( )’ (de alcântara machado, ), which centred not on the male teams but on two young women in the crowd. one of them, romantically attached to a star player for palestra, encourages her boyfriend to kick her ex-partner, now playing for corinthians, suggestive of women’s vicarious – and vigorous – participation in the action on the pitch. in similar vein, argentinian roberto arlt wrote disparagingly of a ‘regimiento de mujercitas de aspecto poco ediicante’ (army of women of unedifying appearance) he saw in the stands at a match between uruguay and his native argentina in his essay ‘ayer vi ganar a los argentinos’ (yesterday i watched argentina win), one of the hugely popular aguafuertes he wrote for the buenos aires newspaper el mundo. © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. david wood by contrasting them with the beautiful girls who lined the streets of buenos aires once he had left the stadium, arlt reveals that the public performance of gender through football was unacceptable, at least in his eyes and – it is implied – those of his readers. like other modes of textual production dominated by men in the early decades of the twentieth century, short stories, chronicles and essays contributed to the development of football as a public discourse and domain characterised by its hegemonic masculinity. football as a female discourse: brazilian pioneers arguably the irst woman in latin america to construct a position for herself as a public subject in relation to football, anna amélia de queiroz ( – ) was a poet, liter- ary translator and prominent member of brazil’s early feminist movement. she requested a ball and football boots for her twelfth birthday (coutinho, : – ), and as a young woman was a regular member of the crowd at matches in rio, where she met marcos de mendonça, goalkeeper for fluminense and the brazilian national team. the couple married in and in anna amélia published the sonnet ‘o salto’ (the leap) inspired by her husband’s performance in goal, thus providing the irst football literature written by a woman in latin america, or indeed anywhere. as its poetic form suggests, ‘o salto’ engages signiicantly with the european classical tradition and makes repeated references to sporting heroes of ancient greece, whose ranks her husband joins through the graceful athleticism of his leap to meet the ball. at the same time, however, as she draws on a conventional and highly stylised discourse around athletic action as a male domain, she also expresses the erotic charge of watching her husband, describ- ing how ‘todo o meu ser vibrou num ímpeto frenético’ (my entire being trembled in a frenetic impetus) and ‘estremeci itando esse teu porte estético’ (i shuddered gazing on your aesthetic bearing). although she is watching the game from the side of the pitch, her voice as a poet enables her to construct a position for herself as a subject who simultane- ously occupies the conventionally private domain of emotional response and the public domain of the football match to invert the heterosexual gaze and challenge conventions around the expression of female eroticism. the practice of football by women was largely mocked in the brazilian media in the s, as discussed above, but the country’s successful participation in the world cup inals in france led to the representation of football by another outstanding woman poet. gilka machado had previously gained notoriety among conservative sectors of society for her expression of women’s erotic experience, but sublimação (sublimation, ), in which she published the lengthy ‘aos heróis do futebol brasileiro’ (to the heroes of brazilian football), marked a shift to a preoccupation with issues of a broader, more social nature. the poem opens in the irst person as the poet salutes the country’s footballing heroes, whose excellence on the pitch has created ‘uma epopéia interna- cional!’ (an international epic!) in terms that echo the references to greek olympians in ‘o salto’. however, as the poem progresses, the initial distance between the players and the brazilian people is reduced and the national team becomes a symbol for the nation as a whole. in contrast to the teams that had represented brazil at the world cup in and , with limited success, the team that reached the semi-inals in france consisted primarily of black players, selected from clubs across the country, and machado’s celebration of the team focuses on two of them, striker leônidas and cen- tral defender domingos da guia. the poet’s description of the ‘penetração/dos gols de leônidas’ (penetration/of leonidas’s goals) hints at the erotic charge of her previous © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. the beautiful game? poetry, and the celebration of a black player’s physicality by a white woman revealed the extent to which women were able to draw on football to offer alternatives to patri- archal norms. the poem closes with machado referring to the players’ achievements as creating ‘um debuxo maravilhoso/do nosso desconhecido país’ (a marvellous drawing/of our unknown country), the use of the irst person plural making clear that she includes herself as part of the nation that she constructs through football. in providing her own interpretation of the team from the perspective of a woman who invests the black play- ers with erotic overtones and explicitly includes herself as part of the imagined national football community, machado offers a vision of the sport that, to some degree at least, runs counter to its elaboration from within hegemonic masculinities of the time. banned in brazil: the dificult decades ( – s) just three years after machado’s representation of football as a national team that included women, the national sports council of president vargas’s estado novo banned women’s football under decree law ( ), which stipulated in article that ‘Às mulheres não se permitirá a prática dos esportes incompatíveis com as condições de sua natureza’ (‘women will not be permitted to practise sports that are incompatible with the conditions of their nature’). the effect of this decree was to block women’s participation in football in brazil – where the greatest involvement had been evident – for several decades, while socially conservative regimes elsewhere in the continent during the s and s did little to promote women’s involvement in the sport. despite the continuing ban, there are indications that brazilian women had continued to play football through to the early s, when they were emboldened by the socially progressive government of president goulart. any sense of opening or of challenge to football’s connection to hegemonic masculinity as national practice, irmly established via the seleçao’s victories in the and world cups, was soon quashed after goulart was overthrown by a right-wing military coup in that ushered in a far more conservative era. in the following year, the national sports council invoked decree law from to close down any openings that were being used by women, declaring via ‘deliberação n. ’ (deliberation number ) that não é permitida a prática de lutas de qualquer natureza, futebol, futebol de salão, futebol de praia, polo-acuático, polo, rugby, halteroilismo e baseball (the practice of physical contests of any kind is not permitted: football, futsal, beach football, water polo, polo, rugby, weightlifting and baseball). despite the legal and socio-cultural obstacles to the practice of women’s football, however, women were far from absent from the realm of football as the national sport in brazil and other countries of the region. by the late s, at the same time as the practice of women’s football began to enjoy a degree of visibility in countries such as chile (elsey, ) and peru, female fans had become a celebrated aspect of the matchday experience in some of the region’s most well-known clubs. in brazil, elisa of corinthians won the prize as the club’s num- ber one fan as early as , and in dulce rosalina became the irst female leader of an organised fan club with vasco da gama’s tov, also winning the revista do esporte’s award for brazil’s best fan in (da costa, : ). in neighbouring argentina, la raulito and la gorda matosas were synonymous with boca juniors and river plate respectively from the s onwards, although it is worth noting that they both underwent a process of masculinisation during a period characterised by fútbol fuerza (strength football) and are celebrated primarily in terms of their transgressive © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. david wood behaviours. maría esther duffau took on a boy’s name, clothing and appearance to become la raulito, described on the dvd of her biopic as ‘una muchacha asex- ual de apariencia masculina’ (an asexual girl of masculine appearance). for her part, haydée luján martínez experienced a simultaneous de-sexualisation and synecdoche to gain her nom de guerre through an emphasis on her corpulent physique and the gift of a shirt from the uruguayan river plate defender roberto matosas, which she then wore to every match. these observations run counter to the indings of a more recent study of women’s football in argentina, which suggests that by the turn of the millen- nium women at football grounds ‘no pierden sus atributos femeninos, antes bien, los exponen’ (do not lose their feminine attributes; rather, they display them) (binello etal., : ), resulting in acceptance at matches by men, whose heterosexuality and nor- mative gendered behaviour thus goes unchallenged. be this as it may, the emergence of right-wing dictatorships in chile, argentina and elsewhere across the continent in the – s resulted in a general closing down of cultural spaces in which traditional gender roles might be challenged, including women’s active participation in football. ‘screwed’ as female football writers: the case of clarice lispector a signiicant challenge to the stereotypes around women’s involvement in football is found in the texts published by brazil’s clarice lispector in the late s as brazil pre- pared for the world cup. author of a weekly column in the inluential rio daily jornal do brasil from to , lispector’s contribution on march was entitled ‘armando nogueira, o futebol e eu, coitada’ (armando nogueira, football and me, screwed), a title that was doubly challenging in its focus on football and in the use of traditionally masculine language. despite proclaiming her ‘ignorância apaixonada por futebol’ (passionate ignorance of football), lispector declares her support for botafogo, although her attendance at a single match makes her feel that ‘isso é tão errado como se eu fosse uma brasileira errada’ (this is as bad as if i were a bad brazilian). associating football with brazilian identity was nothing new, but to include the sport as an inte- gral component in the construction of female brazilian identity continued to present a challenge to normative views. lispector also feminises football through her description of the sport in terms of its ‘beleza própria de movimentos’ (own beauty of movement) and gently mocks the ban on women’s practice of football by stating that she fears she would be sent off for violent conduct were she to play. the author closes her text, written in response to a challenge by renowned football chronicler armando nogueira, with a challenge of her own, inviting him to write a piece about his personal life, which would involve a crossing of the gendered boundaries of public discourses of the time in the opposite direction. in the months following the publication of her irst football text, lispector conducted interviews with two of the country’s leading football managers, both of which featured in the hugely popular glossy magazine manchete. in her interview with the manager of botafogo, mário zagallo, which appeared on july , lispector draws on the notion of football as an aesthetic practice, prefacing the interview with the epigraph ‘o futebol é uma arte’ (football is an art), words uttered by zagallo during the course of the interview. more daring is her description of him as ‘ino de corpo, as pernas não são deformadas por uma musculatura violenta’ (slim-bodied, his legs are not deformed by a violent musculature) (williams, : ), the de-masculinisation of football extending here to the physique of one of its most respected practitioners. joão saldanha, then © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. the beautiful game? manager of the national team that would go on to win the world cup in mexico city to universal acclaim under zagallo, receives similar treatment in an interview published on june , being described as ‘um homem bonito’ (a nice-looking man) (williams, : ), whose nonchalant air excites women. he too states that ‘futebol é arte’ (football is art) (williams, : ), but of greater note is the text that precedes her opening question to saldanha: este diálogo foi especialmente escolhido tendo em vista o interesse das mul- heres pelo futebol. e um jogo masculino, mas a frequencia femenina nos estádios aumenta cada dia mais. [ … ] o meu diálogo serve também para a mulher entender um pouco de futebol. (williams, : ) this interview was specially chosen bearing in mind women’s interest in football. it is a masculine game, but the presence of women in stadia is increasing daily. [ … ] my interview also serves for women to understand a bit about football. in addition to the stated interest of women in football, to the degree that it justiies a piece in the country’s most widely read magazine, and their growing presence at matches, lispector lays claim to the dialogue as hers. by demonstrating an excellent knowledge of squad selection, tactical formations and the history of the world cup that is com- pletely at odds with her previously stated passionate ignorance, she engages saldanha on an equal footing as someone completely at home in the discourse of football. her ownership of the text is apparent too within the transcription of the interviews, both of which are punctuated by her relections on the male football icons before her. in the case of saldanha, these additions serve to introduce his wife to the scene and to emphasise lispector’s parity as they drink coffee and smoke together, concluding with a shared desire for victory in . towards the end of her interview with zagallo, lispector provides additional material to describe, in highly patronising terms, his features as he considers his response to a dificult question: ‘seu rosto demostrava o esforço mais bonito do homem: o esforço de pensar e de se autoconhecer’ (his face revealed man’s most beau- tiful effort: the effort to think and know himself) (williams, : ). and when he inally replies, she refuses to accept his response before telling the reader what she feels he really wanted to say. through the combination of the features discussed above, lispector asserts her authority as a female writer in what she describes – in terms the reader can now see as ironic – as ‘um jogo masculino’ (a masculine game) (williams, : ). by displaying her position of authority in relation to two of the most inluential men in football at the time, taking the role of interviewer, being at ease with the terminology of the game and conveying the dificulties that the eloquent zagallo in particular encoun- tered in expressing answers to her questions, it is clear that this is no longer simply a man’s game. creating space: the s and s paradoxically, the existence of a ban on women’s football in brazil meant that when this was removed, under president geisel’s policy of distensão in , the impact was more signiicant than in countries where the relaxation of restrictions on women’s roles was less clearly marked. although women’s football in brazil was only formally recognised by the national sports council in , it boomed in the early s, with as many © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. david wood as women’s teams and organised championships for these teams in eleven states (goellner, : – ; knijnik, : – ). such levels of participation were unique to brazil, where football had become an integral component of national iden- tity for many women as for men, and where the emphasis on an aestheticised futebol arte had been embraced most fully as a response to the more overtly masculinised fute- bol força advocated by the military dictatorship through the s (kittleson, : ). it is important here to note that the low proile of the women’s game was not restricted to the rest of latin america, and it was only in the wake of calls from norwe- gian delegates at the fifa congress in mexico city that women’s football came to be recognised and supported by fifa. the most visible outcome of this was the irst ‘oficial’ women’s world cup, held in china in , at which brazil was latin amer- ica’s sole representative. following the success of this tournament, women’s football was admitted to the olympic games in atlanta, almost a century after men’s football irst featured in the paris games, with brazil once again the only latin american team present. the third wave of athletic feminism in the s, of which the rise in international women’s football is an important strand, coincided with a period of political liberali- sation across south america after various long-standing dictatorships had relinquished power and traditional restrictions on women’s roles were once again open – at least in part – to signiicant challenge. one of the most striking features of this process through- out latin america was the emergence of women as actors in national politics and the fact that women have in recent years served at least one presidential term in the countries where women’s football has enjoyed high levels of visibility and/or international success (argentina, brazil, chile and costa rica). the everyday experience of women enacting political power as representatives of the nation, a function hitherto almost exclusively the preserve of men in latin america, has to be seen alongside the symbolic power increasingly attributed to women as football players, two key facets of recent challenges to hegemonic masculinity in the region. the rise of female football stars: marigol and marta as women’s football has become increasingly widely practised across latin america in recent years, it has also come to enjoy greater public visibility through various means, involving both printed and electronic mass media. studies of this still recent phenomenon are to date scarce, but conirm this trend in both brazil and argentina (binello etal., ; votre and mourão, ; goellner, ; mourão and morel, ; knijnik, ). the twenty-irst century has seen the emergence of the irst women football super- stars on the continent, celebrated for their ability with the ball and their achievements on the pitch. maribel domínguez, the star forward of the mexican women’s team, scored goals in appearances between and , a record that earned her the nick- name ‘marigol’. a skilful and quick player, she signed for mexican second division club celaya in december in response to the absence of a professional women’s league in the country. the move, however, was blocked by fifa, whose ruling on the case stated that there must be a clear separation between men’s and women’s football, to which there would be no exceptions (tuckman, ). the case of domínguez reveals repeated obstacles to the practice of women’s football across latin america: after her initial desire to play foundered on her father’s disapproval, she began to play in boys’ teams after his death, gaining acceptance by pretending to be a boy, known to her © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. the beautiful game? team-mates as mario (las guerreras del tri, ). the physical appearance she cul- tivated that allowed for the deception, in addition to the football skills she developed during those years, subsequently caused problems when she was forced to undergo a full body inspection on joining a women’s team in because of her ability to play like a man (grainey, : – ). marigol’s case reveals how, despite her public recognition through footballing prowess, women and football occupy spaces that into the twenty-irst century continue to be seen by many – including the international gov- erning body – as gender-determined, and all too often as mutually exclusive. even more well-known than domínguez, brazilian marta vieira da silva is arguably the greatest woman football player of all time. fifa’s world player of the year for ive consecutive years between and (she was runner-up on a further four occa- sions) and all-time leading goalscorer at the women’s world cup, marta has joined the ranks of football’s international superstars in being immediately recognisable by a single name. however, in contrast to her male counterparts, such as maradona, zico or pelé, in her case it is a irst name that stands as a gendered marker of her status as a woman, and her ability has been repeatedly framed in terms of the skills of male players, pelé himself celebrating her ability by declaring that ‘a marta é a pelé de saia’ (marta is pelé in a skirt) (paiva, ). notwithstanding such considerations, marta was named as one of six football ambassadors for the world cup in brazil and on june inaugurated rio’s football for equality plaza, where a multi-media exhibition ‘women on the pitch’ explored almost a hundred years of women’s football in brazil. at the women’s world cup in the united states, the last before marta broke into the national team, the renowned football chronicler armando nogueira, challenged by lispector in her article discussed above, explained the lack of support for women’s football in brazil as follows: unfortunately, women’s soccer doesn’t have a chance in brazil. the best woman player in brazil will never be as popular as the worst male player, and the main reason is that women have been idolized as delicate objects of desire, incapable of playing a physical-contact, body-to-body sport. (cited in grainey, : ) it is unclear whether these are the views of nogueira himself, but they offer a direct echo of the law that prohibited women from playing football, even if that law had been revoked a full twenty years prior to his declaration. what is clear is that less than two decades later such a view would be unsustainable in the face of marta’s success, which resulted in her being one of eight brazilians selected to carry the olympic lag during the opening ceremony at the rio olympic games. her strong performances as cap- tain of the women’s team in the group matches, which they won convincingly, played out in marked contrast to the disappointing results of the men’s team, captained by neymar, also wearer of the iconic number shirt. indeed, large sections of the crowd chanted her name during the - draw between the brazilian men’s team and iraq and pictures of national team shirts on which neymar had been crossed out and replaced with marta enjoyed wide circulation on electronic and social media (pina, ). ulti- mately, however, the women’s team lost on penalties in the semi-inal and the men’s team recovered from their poor start to defeat germany in the inal, neymar scoring both a free kick during normal time and the decisive penalty that earned brazil their irst olympic football title. the transruptive potential of marta’s success and iconic status was only partly realised: the threat to hegemonic masculinity, and to the historical con- nection between masculinity, nationhood and football dissipated as the ‘normal’ order, © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. david wood where men’s football served to represent the nation to local and international audiences alike, was restored. that this championing of marta’s symbolic power came weeks after president dilma rousseff had been suspended from ofice ahead of her eventual impeach- ment, and that she and her diverse government had been replaced by a male president and an all-male cabinet, is intriguing, suggestive of new levels of connectivity between women’s symbolic and political power. public portrayals of women’s football notwithstanding the achievements of igures such as marta and maribel domínguez, representations of women’s football have tended to coincide with an ongoing erotici- sation of the female body, an emphasis on the ‘feminine’ qualities of players who are framed within a heterosexual male gaze. this situation resonates with that described in studies carried out in the united states, according to which these “feminized” images represent a modernized attempt to reinforce traditional stereotypical images of femi- ninity and female sexuality, such portrayals constituting a mode of ongoing patriarchal control over women and their bodies (kane and greendorfer, : – ). perhaps the most infamous example of hegemonic masculinity’s insistence on emphasised fem- ininity in latin american football was the decision in by the são paulo foot- ball federation to start a women’s championship, for which they called hundreds of women to trials. the preference for blonde, fair-skinned players over more talented darker-skinned players, the banning of short haircuts and an upper age limit of led to the organisation being formally denounced to the public prosecutor (knijnik, : – ). in the context of argentina, the authors of a study of women’s football there conclude that: tanto las representaciones como las prácticas reproducen las gramáticas de producción pertenecientes al universo simbólico masculino, y no aparecen intenciones de prácticas que permitan habitar dominios culturales de la masculinidad de otro modo que no sean los modelos deinidos cultural- mente. (binello etal., : ) both the representations and practices reproduce grammars of production that belong to the masculine symbolic world and there is no sign of practices that allow for the masculine cultural domain to be inhabited by any means other than culturally deined models. while their study focused solely on argentina, the indings can be seen to apply across the continent, evident as much in the everyday media discourses that routinely sexualise women footballers as in oficial initiatives such as the logo reproduced in figure . at the same time as it provides a powerful example of the continued presence of hege- monic masculinity, even within a tournament for women, this image is also a reminder that discourses around football in latin america interact with those elsewhere, echoing the movement of players to women’s leagues in europe and the united states. adapted from a advert for sky tv that featured the black stiletto football boot and an accompanying slogan ‘football explained to women’, created by milan-based advertis- ing agency united, it illustrates the degree to which football’s association with hegemonic masculinity extends well beyond latin america as part of the low of images within global capitalism. © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. the beautiful game? figure . poster for the under- south american women’s football championship source: alexander mantilla. reproduced under creative commons licence cc by-sa . . in the wake of the women’s world cup, which saw the participation of ive teams from latin america, women’s football has become an increasingly normalised feature of print and electronic media. mexico’s matches in canada were broadcast across the country by three channels, colombia’s matches were shown on caracol tv, and the brazilian team’s participation at the tournament was free to view on the federal government’s tv brasil, which has since also shown matches from the newly created campeonato brasileiro feminino. national newspapers ran features on the women’s teams and followed their fortunes at the women’s world cup, which on the whole compared favourably with their male counterparts at the concurrent copa américa. in the context of the olympic women’s football tournament in rio , the furore at the lack of brazil shirts featuring marta’s name in sizes appropriate for men, and the crossing out of neymar’s name on the iconic no. shirts to be replaced by marta’s, provided a potent symbol of a woman footballer becoming widely acclaimed as representative of the nation, perhaps for the irst time in latin america. such episodes enjoyed viral coverage through social media, which offer routes of expression that may circumvent the hegemonic masculinity of traditional media, while in the realm of electronic gaming brazil (and mexico) feature among the women’s teams that appear © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. david wood in ea sports fifa for the irst time. in contrast to the notion that the femini- sation of football in brazil may have extended to the women’s team appropriating the national style of the beautiful game (bowman, ), the colombian team are routinely described in print media and social media alike as ‘las superpoderosas’ (the super-powerful). for their part, the mexican and ecuadorian women’s teams are known as ‘las guerreras del tri’ and ‘las guerreras de la tri’ (the warriors of the tricolour) respectively, aligning their endeavours to the national lag. instead of football being feminised through their achievements, it instead appears that by representing the nation via football the women on the teams come to acquire traditionally masculine character- istics that enable them to enter the realm of national iconography. in uruguay, where football and gendered nationhood are closely aligned through the heavily masculinised notion of the garra charrúa (indigenous ighting spirit), the relative underdevelopment of women’s football in relation to the men’s game leads lucía pimentel to ask whether women’s resulting lack of involvement in the construction of national identity renders the sport there ‘un relato parcializado’ (a partialised or biased narrative) (pimentel, : ). this situation is perhaps symptomatic in a country that igures at (or near) the bottom of tables for women ministers and women parliamentarians in latin america (oecd, : ). conclusions over the course of the last hundred years there is no doubt that the relationship between women and football in latin america has undergone fundamental changes that are both quantitative and qualitative in nature. media reports, chronicles and short stories have included women as part of the footballing landscape since at least the early s, as players, as spectators and, in some cases, as authors of texts that drew on the game for their creative inspiration. the production of discourses on women’s football from a male perspective during this period was challenged on rare occasions by women writers who subjected men’s football to a female gaze, but the dominant narratives culminated in the banning of women’s football in brazil in , symbolic of the wider exclusion of women as players of the game at a continental level. radical political developments through the s, combined with changing attitudes to women’s position in society, led to rapid changes in the socio-cultural landscape, in which women’s football began to appear with some force, only largely to disappear again under the dictatorships that held sway across much of the region in the s, although mexico provided a notable exception. it was only following the return to democracy in the s, and the emergence of third-wave feminism that continued to challenge masculine control – both literal and symbolic – over the female body, that women’s national teams, national leagues and international tournaments arose across latin america. the symbolic power achieved by women in recent years as a result of their excellence in various public domains of footballing practice and representation must be under- stood alongside the election of women presidents in argentina, brazil, chile and costa rica, especially the re-election of cristina fernández de kirchner in argentina and dilma roussef in brazil. both presidents acknowledged the signiicance of football via their vis- ibility around the world cup in brazil, and there is evidence of movement in the other direction as women footballers convert the symbolic power they have gained in a previously masculine domain into political power through public positions. in addition to the profoundly symbolic national roles she has occupied, described above, marta © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. the beautiful game? has, since , been a goodwill ambassador for the un development programme, while maribel domínguez made her irst incursion into politics with partido acción nacional (pan, national action party) in the state of hidalgo for elections held in march . latin american women from other sports, such as mexican ana gue- vara (athletics) and peruvians cecilia tait, gabriela pérez del solar, cenaida uribe and leyla chihuán (all volleyball), have entered national politics since the turn of the mil- lennium, and whether or not women footballers go on to do so they have already made an arguably more signiicant contribution to challenging norms around the public pres- ence of women in a key realm of national life. the growing presence of women in the practice and discourse of football marks a clear trend towards the representation – and, crucially, self-representation – of female agency in the sport, simultaneously symptom and cause of a challenge to hegemonic masculinity across the region. however, as some of the examples discussed here have shown, the ongoing representation of that presence often remains problematically constructed (implicitly at least) via a masculine gaze that sexualises female players and fans alike. las superpoderosas, las guerreras de la tri, marta and marigol, like women footballers across latin america, are not only play- ing the opposition, but also gender conventions and deeply ingrained cultural norms that continue to be experienced on a daily basis throughout the region. it is almost years since messner drew attention to the manner in which women’s greater partic- ipation in us sport constituted a challenge to the ideological basis of male domination ( : ), while at the same time acknowledging that the framing of that participa- tion remained subject to perspectives that tended to obstruct their counter-hegemonic potential. more recently, connell ( ) called for a reconsideration of masculinities from a perspective that moves beyond the global north, advocating a decolonisation of debates around masculinity. messner’s portrayal of the female athletic body as a con- tested ideological terrain (messner, : ) may continue to hold true in the context of twenty-irst century latin america, but at the same time women’s football in brazil and argentina reveals how that process of contestation has been under way for the best part of a century. this is a ield that has much to offer ongoing debates around the ways in which individual subjectivities and national identities are constructed in terms of hegemonic masculinities, while also undoubtedly having a part to play in relation to the decolonisation of such issues. references alabarces, p. 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( ) entrevistas/clarice lispector. rocco: rio de janeiro. © the authors. bulletin of latin american research published by john wiley & sons ltd on behalf of the society for latin american studies. bulletin of latin american research vol. , no. http://esportes.terra.com.br/pequim /interna/ ,,oi -ei , -pele+diz+que+marta+e+sua+versao+de+saia.html http://esportes.terra.com.br/pequim /interna/ ,,oi -ei , -pele+diz+que+marta+e+sua+versao+de+saia.html http://esportes.terra.com.br/pequim /interna/ ,,oi -ei , -pele+diz+que+marta+e+sua+versao+de+saia.html http://globoesporte.globo.com/am/olimpiadas/noticia/ / /virou-moda-torcedores-em-manaus-trocam-neymar-por-marta-em-camisa.html http://globoesporte.globo.com/am/olimpiadas/noticia/ / /virou-moda-torcedores-em-manaus-trocam-neymar-por-marta-em-camisa.html http://www.theguardian.com/football/ /jan/ /womensfootball.sport http://www.theguardian.com/football/ /jan/ /womensfootball.sport jin .indd e-mail karger@karger.com editorial j innate immun ; : – doi: . / the neutrophil: a beautiful beast or a beastly beauty? phenotype are not known. in this issue, sawant et al. [ ] present highly interesting data showing that cxcl monomer-dimer distribution and receptor interactions are highly coupled and regulate neutrophil trafficking, and that injury in the context of disease is a consequence of inappropriate cxcr activation at the target tissue [ ] . the classic view is that neutrophils are important in bacterial killing [ ] . however, they can also recognize damage-associated molecular patterns (damps) during tissue-damage and participate in viral host defense [ , ] . another important function is the formation of neu- trophil extracellular traps (nets), formed during an ac- tive cellular process where the neutrophil releases its dna to the extracellular environment [ , ] . finally, resolution of neutrophil inflammation has to be tightly regulated to avoid accumulation of these cells, as is exem- plified by the prolonged and excessive inflammation in cystic fibrosis [ – ] . the rapidly increasing knowledge regarding the im- munobiology of this fascinating and important cell should attract the attention of a broad readership interested in innate immunity. heiko herwald , lund arne egesten , lund neutrophils are crucial to keeping us in a healthy state, but they also play important roles in the pathophysiology of a broad spectrum of diseases [ ] . early on, they were regarded as quite primitive cells, simply executing cyto- toxic functions. it has become evident, however, that they are highly sophisticated and can perform complex func- tions in many inflammatory contexts. neutrophils origi- nate from stem cells in the bone marrow where growth factors induce sequential expression of genes, resulting in a distinct phenotype, not least characterized by its differ- ent sets of cytoplasmic granule containing preformed host defense proteins ready to be released at sites of in- flammation [ ] . being transported in the bloodstream, specific adhesion molecules expressed by endothelial cells and chemotactic gradients are important for neutrophil recruitment and activation [ – ] . elr-positive cxc chemokines, including il- / cxcl , are important during this process. interestingly, there are two receptors for this group of ligands with varying affinities [ – ] . cxcl mediates neutrophil re- cruitment by binding and activating cxcr , and inhibi- tion of this receptor shows that dysregulation of cxcl / cxcr function is correlated with the severity of disease [ ] . however, the mechanisms that turn the beneficial cxcl -mediated neutrophil functions into a destructive published online: september , journal of innate immunity © s. karger ag, basel – x/ / – $ . / www.karger.com/jin herwald/egesten j innate immun ; : – doi: . / references nauseef wm, borregaard n: neutrophils at work. nat immunol ; : – . daniel ae, van buul jd: endothelial junct- ion regulation: a prerequisite for leukocytes crossing the vessel wall. j innate immun ; : – . grommes j, drechsler m, soehnlein o: ccr and fpr mediate neutrophil recruitment in 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christenson k, björkman l, karlsson a, by- lund j: regulation of neutrophil apoptosis dif- fers after in vivo transmigration to skin cham- bers and synovial fluid: a role for inflamma- some-dependent interleukin- β release. j innate immun ; : – . dwyer m, shan q, d’ortona s, maurer r, mitchell r, olesen h, thiel s, huebner j, gadjeva m: cystic fibrosis sputum dna has netosis characteristics and neutrophil extra- cellular trap release is regulated by macro- phage migration-inhibitory factor. j innate immun ; : – . strydom n, rankin sm: regulation of circu- lating neutrophil numbers under homeostasis and in disease. j innate immun ; : – . extrafloral nectary–the sleeping beauty of plant science comment open access extrafloral nectary–the sleeping beauty of plant science chen xiaoya abstract cotton is one of the most important cash crops, its growth season coincides with a high incidence of diverse groups of pests, leading to heavy use of pesticides. recent identification of a signaling protein as a candidate regulator of cotton extrafloral nectary provides a new insight into the formation of sophisticated defense mechanisms in plants. keywords: extrafloral nectary, pb domain, ganec i, cotton, gossypium, indirect defense, insect main text extrafloral nectary is an indirect defense device of plants and can be located on the shoot, leaf stalks, leaf blades or stipules, or on the inner or outer surfaces of the sepals but not involved in pollination (heil ). however, its formation in crops and potential role in biocontrol of pests and diseases are under studied (stenberg et al. ). nectar, a sweet aqueous secretion consisting of sugars, amino acids and secondary me- tabolites, mediates the interactions of plants with pollinators and defenders (heil ). more than angiosperm species including cotton (gossypium spp.) produce extrafloral nectar- ies to attract mutualistic animals to catch herbivores. the ex- ists of extrafloral nectarines in cotton speices are slightly different, since g. gossypiodes (d ) and allotertraploid g. tomentosum (ad ) have no nectarines on the midribs of leaves (hu et al. ). cotton accessions with variations in extrafloral nectaries, combined with the progresses in cotton genomics (li et al. ; hu et al. ; li et al. ; du et al. ; ma et al. ; yang et al. ; yang et al. ; zhang et al. ) provide an unprecedented opportunity to elucidate the genetic basis of nectar formation and ecological functions. recently, li, yang and colleagues from institute of cotton research of chinese academy of agricultural sci- ences, identified the causal quantitative trait locus (qtl)/gene for the cotton extrafloral nectary and revealed the genomic differences in the causal qtl regions as well as the potential network regulating nectary formation (hu et al. ). uncov- ered molecular details about nectary formation could be ap- plied to molecular breeding of cultivars that confer pest- resistance via biological control. through investigating the extrafloral distribution in different species, hu et al. found that the nectary was present in the common ancestor of kokia and gossy- pium. the nectariless trait was thus derived from natural mutation. based on a core collection of g. arboreum accessions, they compared the extrafloral nectary- bearing to the nectariless accessions and found a region of chr showing strong differentiation and overlapping with the qtl region identified via genome-wide ana- lysis. they further narrowed the candidate genes to a kb region using an f population, and validated ganec , encoding a phox-bem (pb ) domain- containing protein, as a regulator of nectary formation. they found that a deletion of five amino acids, together with a nonsynonymous substitution, probably caused structural alteration in the ganec protein and confer the nectariless phenotype. silencing of ganec led to a smaller foliar nectary phenotype. further, they found that the jasmonate (ja) related genes were up-regulated and the cell wall genes were down-regulated in the nec- tary. they also performed metabolomics analysis of the nectary secretion and identified more than nectar components, including the expected saccharides and amino acids. © the author(s). open access this article is licensed under a creative commons attribution . international license, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the creative commons licence, and indicate if changes were made. the images or other third party material in this article are included in the article's creative commons licence, unless indicated otherwise in a credit line to the material. if material is not included in the article's creative commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. to view a copy of this licence, visit http://creativecommons.org/licenses/by/ . /. correspondence: xychen@sibs.ac.cn cas center for excellence in molecular plant sciences/shanghai institute of plant physiology and ecology, chinese academy of sciences, fenglin road, shanghai , china journal of cotton researchchen journal of cotton research ( ) : https://doi.org/ . /s - - - http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf http://creativecommons.org/licenses/by/ . / mailto:xychen@sibs.ac.cn the pb domain is conserved in eukaryotes and modu- lates protein interactions. identification of a pb domain- containing protein as a regulatory component of the extra- floral nectary formation and sheds a light on the molecular mechanism underlying the evolution and development of this adaptive sweet apparatus and can be an important pro- gress in this filed. hopefully the finding will stimulate further investigation of various aspects of nectaries in flowers and other parts, which will help develop environmentally friendly, healthy and beautiful strategies for pests control. acknowledgments the author thanks dr. liu ningjing and wang lingjian for critical reading of the manuscript. author’s contributions chen xy prepared and wrote the manuscript. the author read and approved the final manuscript. funding not applicable. availability of data and materials no other data related to this study is available at this time. ethics approval and consent to participate not applicable. consent for publication not applicable. competing interests the authors declare that they have no competing interests. received: february accepted: march references du x, huang g, he s, et al. resequencing of diploid cotton accessions based on an updated a genome identifies the genetic basis of key agronomic traits. nat genet. ; : – . https://doi.org/ . /s - - -x. heil m. nectar: generation, regulation and ecological functions. trends plant sci. ; : – . https://doi.org/ . /j.tplants. . . . hu g, 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author’s contributions funding availability of data and materials ethics approval and consent to participate consent for publication competing interests references journal of innovative technology and education, vol. , , no. , - hikari ltd, www.m-hikari.com https://doi.org/ . /jite. . truth, goodness and beauty in mathematics teaching xilian fu school of mathematics and statistics shandong university of technology zibo, , china this article is distributed under the creative commons by-nc-nd attribution license. copyright c© hikari ltd. abstract mathematics is the unity of truth, goodness and beauty. in mathe- matics teaching, we should embody three levels of content: the impart- ing of knowledge and methods - reflecting the truth of mathematics; the application of thoughts and methods - reflecting the goodness of mathematics; the appreciation of mathematics - reflecting the beauty of mathematics. thus, the combination of rational spirit and humanistic spirit of mathematics can be realized, and the unity of truth, goodness and beauty in mathematics education can be achieved. mathematics subject classification: a keywords: mathematics teaching; thought and method; mathematics beauty; mathematics spirit introduction as one of the oldest disciplines in the long history of mankind, mathematics has become a major discipline with the same status as natural science, social science and thinking science after a long period of accumulation in elementary mathematics to the birth of modern mathematics in the th century, and then to the rapid development of modern mathematics. throughout the history of mathematics development, the solution of every major problem shines with the brilliance of human thought. the establishment of every theory reflects the xilian fu wisdom of mathematicians and perspectives the spirit, concept and attitude of mathematics. mathematics is not only a tool, a technology, but also a culture, an art. mathematics is the unity of truth, goodness and beauty. in mathematics teaching, we need to embody three levels of content: that is, the imparting of knowledge and methods - reflecting the truth of mathematics, the application of ideas and methods - reflecting the goodness of mathematics; the appreciation of mathematics - reflecting the beauty of mathematics. thus, the combination of rational spirit and humanistic spirit of mathematics can be realized, and the unity of truth, goodness and beauty in mathematics education can be achieved. truth in mathematics teaching the main task of any subject education is to seek truth from teaching. as far as mathematics is concerned, the question of what to teach and how to teach depends on teachers’views on mathematics. different views of mathe- matics form different values of mathematics, which determines the structure of mathematics knowledge and the way of training talents in the process of math- ematics education. the traditional view of mathematics is often pragmatism or scientism. although it has certain rationality, it can not reflect the char- acteristics of mathematics comprehensively and profoundly. this leads to the fact that in the traditional mathematics teaching process, teachers only con- centrate on the imparting of knowledge and the formation of skills, but neglect the most charming rational spirit contained in mathematics knowledge. from a scientific point of view, mathematics is a systematic theoretical sys- tem consisting of knowledge and methods and thought with a rigorous struc- ture from a scientific perspective. from the cultural point of view, although the definition of mathematical culture has not been fully defined up to now, as a knowledge of mathematical culture, people have reached a consensus that mathematical culture is different from mathematical history, mathematical philosophy and mathematical methodology; it is neither a general knowledge of mathematical theory nor a statement of some mathematical phenomena. mathematical culture is a deeper content in the process of the generation, development and perfection of mathematical knowledge, that is, the spirit, attitude, concept and method of mathematical science. “scientific culture and instrumental rationality are the source of civilization and the foundation for the establishment of the world; humanistic culture and value rationality are the foundation of civilization and the foundation of human beings”[ ]. therefore, the term “truth” here means that teachers not only impart the definite knowledge in mathematics textbooks, let students master truth, but also let students master the method of obtaining truth, and understand the rational spirit of mathematicians seeking truth and pursuing mathematics teaching truth. the problem is the heart of mathematics, knowledge is the carrier of math- ematics, method is the behavior of mathematics, and thought is the soul of mathematics. in the process of teaching, we should form a constructivist teaching view of mathematics, which regards problems as the logical starting point of classroom teaching design, knowledge as the carrier, ideology as the guidance, cultivating students’scientific spirit as the goal, reconstructing the process of knowledge regeneration,so as to cultivate students’various mathe- matical abilities and improve students’thinking products, quality, and let them feel the scientific spirit. goodness in mathematics teaching “if the truth of mathematics represents is the scientific value of mathematics, goodness of mathematics represents the social value of mathematics”[ ]. in the process of mathematics teaching, if the truth refers to the imparting of knowl- edge and the mastery of ideas and methods, then goodness is the relationship and interaction between mathematics and technology, society, economy and engineering. the development of modern mathematics is characterized by its high degree of abstraction and unity. it is this high degree of abstraction that has led to the wide application of mathematics. the application of modern mathematics produced in the th century is limited to astronomy, naviga- tion technology, mechanics, physics and other fields. the thought and method of modern mathematics has penetrated into almost all fields of economy and society, and increasingly affects human life. in the s, british mathematician and mathematic logician whitehead pointed out in his famous speech-mathematics and goodness: “considering that mathematics has infinite subject matter, mathematics and even modern mathematics are still a science in infancy. if civilization continues to develop, then in the next two thousand years, the overwhelming new feature of human thought is the dominance of mathematical understanding”[ ]. therefore, the application of mathematics should be emphasized in today’s higher and higher degree of mathematicalization in science, technology, society and economy. firstly, the practical background, mathematical significance and scientific value of the emergence of mathematical theory are expounded from a histor- ical point of view. secondly, facts and data are used to illustrate the role of mathematics in promoting the national economy and its impact on our lives. thirdly, strengthen the connection with other professional courses and carry out case teaching. fourthly, set up practical application examples with certain difficulties, let students work on their own, use the knowledge and methods they have learned to establish mathematical models, and solve these problems independently. through the teaching strategy of integrating theory with prac- xilian fu tice, students can realize the purpose of learning mathematics, stimulate their interest in learning mathematics, and finally form a correct mathematical at- titude, that is, to learn to observe things mathematically, understand things mathematically, and solve practical problems mathematically. “mathematics is regarded as a rational way of thinking beyond concepts and methods, the best way to express the world and a belief in“near”truth. it is recognized that the use of the useless is the core of mathematical development”[ ]. beauty in mathematics teaching mathematician russell pointed out: “mathematics, if viewed correctly, not only has truth, but also has the supreme beauty, just like the beauty of sculp- ture, is a cold and serious beauty. this beauty is not a weak aspect of our nature. this beauty does not have the gorgeous decoration of painting or mu- sic, it can be pure to the sublime, and it can achieve the perfect situation that only the greatest art can show”[ ]. mathematics is a subject of beauty, because its object of study-mode is an idealized model, idealized model is the product of abstract thinking, implying a symbolic and formal process of representation, reflecting simplicity and harmony, which is naturally beautiful. according to the social and material attributes of mathematical beauty, mathematical beauty can be divided into content beauty and form beauty. the former can also be divided into structural beauty, linguistic beauty and methodological beauty, while the latter is the external and internal perfor- mance of the former. the external performance can be divided into concise beauty, unified beauty, symmetrical beauty and neat beauty. the internal per- formance is characterized by singular beauty and speculative beauty. mathe- matical beauty can be divided into formal beauty, rational beauty and creative beauty according to the hierarchy from surface to interior. mathematical beauty is an abstract beauty, cold beauty, how to turn this cold beauty into hot thinking? first of all, we should show the beauty by the truth, guide students to perceive the formal beauty of mathematics sensibly, and make students realize that mathematics is full of the charm of beauty. sec- ondly, through the external beauty of mathematics, the rational thinking and mathematical beliefs of the mathematicians implied in it are deeply analyzed, including unique and wonderful methods and profound ideas, and the pursuit of strict and unified mathematical beliefs. from this, the unity of content beauty and form beauty can be achieved. thirdly, mathematical aesthetics is often accompanied by mathematical creative activities. mathematical creation can not be separated from mathematical intuition. mathematical intuition is a choice, that is, making the most subtle and essential choice according to aesthetic principles. therefore, in the process of knowledge innovation and application innovation, let students feel and appreciate beauty and learn how mathematics teaching to enlighten truth by beauty. mathematics teaching can not be separated from the analysis of the char- acteristics of mathematics. only mathematics teaching that reflects the truth, goodness and beauty of mathematics can truly achieve the truth, goodness and beauty. references [ ] shuzi yang, mathematics is very important, culture is very important, mathematics culture is also very important, journal of mathematics ed- ucation , higher education press, ( ) – . [ ] qin’an huang, mathematical education under the concept of mathemat- ical culture, journal of mathematics education advanced mathematics, the posts and telecommunications press, ( ), – . [ ] donggao deng, mathematics and culture, beijing university press, ( ). [ ] pengfei liu, from technology to tao: a study of mathematical values, dialectical communication of nature, ( ), – . [ ] benshun xu, qizheng yin, aesthetic method in mathematics, jiangsu education press, ( ). received: september , ; published: october , wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ turkish studies - international periodical for the languages, literature and history of turkish or turkic volume / summer , p. - turkey sevgİlİnİn gÜzellİk unsurlarindan saÇ ve saÇin ÂŞik Üzerİndekİ etkİsİ kürşat Şamil Şahİn* Özet divan şiirinde anlatılan birçok konunun merkezinde hep sevgili vardır. sevgili ile âşığın serüveni hiç bitmez. sevgilinin güzelliği dilden dile dolaşır. sevgiliyi güzel kılan vasıflardan en önemlisi ilk göze çarpan unsurlardan biri olmasından dolayı saçtır. sevgilinin güzellik unsurlarından en çok üzerinde durulan saçın bu önemi, yüzün güzelliğini daha da artırmasından kaynaklanmaktadır. saç, âşığı sevgiliye bağlayan ve onu çok fazla etkileyen bir özelliğe sahiptir. saçlar, âşığı cezbeden aynı zamanda da eziyet eden özellikleriyle karşımıza çıkar. Âşıklar için saçlar yakalanmaktan, bağlanmaktan kaçılamayacak bir güzelliktedir. Âşıkların hem saça bağlanmak istedikleri hem de bağlanmaktan dolayı şikâyet ettikleri görülür. bu makalede genel olarak saçtan bahsedildikten sonra onun âşık üzerindeki etkisini gösteren teşbih, mecaz ve tasavvurlar toplu bir şekilde ortaya konulmaya çalışılmıştır. anahtar kelimeler: sevgili, âşık, güzellik, saç, divan şiiri. an element of beloved’s beauty, hair, and its effect on lover abstract there is always beloved in the center of many issues described in the divan poetry. the adventure between beloved and lover never ends. the beauty of the beloved is talked from mouth to mouth. the most important feature in beloved is hair as it is the first striking element. this importance of hair, the most emphasized the element of beauty in beloved, stems from that it increases the beauty of the face further. hair has a property affecting lover very much and binding lover to beloved. hair is seen in the characteristics of suffering at the same time attracting to the lover. hair has a beauty for lovers inescapable of being caught, being affined to. lovers are seen both to wish to affine to hair and to complain to do so. in this article, after referring to hair in general similes, metaphors and imaginations exposing its effect on the lover are tried to be presented collectively. keywords: beloved, lover, beauty, hair, divan poetry. * bartın Üniversitesi türk dili okutmanı. el-mek: kursatsamil@hotmail.com mailto:kursatsamil@hotmail.com kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer giriş klasik türk Ģiirinin konuları arasında en önemli yeri sevgili teĢkil etmektedir. klasik Ģiirde bazı istisnalar dıĢında anlatılmak istenen ne olursa olsun merkezde hep sevgili vardır ve bütün olaylar sevgili çevresinde Ģekillendirilir. bundan dolayı da onun üzerine yazılanlar ve onu anlatmak için kullanılan sıfatlar çok fazladır. sevgilinin pek çok uzvuyla ilgili benzetmeler yapılmasından dolayı Ģairler için bir rehber hizmeti görmek üzere sevgilinin fiziğiyle ilgili unsurları toplu bir Ģekilde gösteren eserler kaleme alınmıĢtır (akün , ). bu eserlerden en önemlisi ġerâfettin râmî‟nin enisü‟l – uĢĢâk‟ıdır. eserde sevgiliyle alakalı unsurdan bahsedilmiĢtir . kutbiddin ahmed‟in hevesnâme‟si râmî‟nin eserine nazire olarak yazılmıĢtır. (atay , ) kutbiddin ahmed, tasvir edilen uzuvların sayısını artırarak unsurdan bahsetmiĢtir. yine genel hatlarıyla râmî‟nin eserine bağlı olan mu‟îdî‟nin miftâhu‟t-teĢbîh‟i (erünsal , – ), sürûrî‟nin bahrü‟l-maârif‟inin „teĢbîhât ve mesâ‟il-i enîsü‟l-uĢĢâk beyânındadır‟ baĢlıklı bölümünde (ġafak , – ) unsurdan bahsedilmiĢtir. benzetmeler sözlüğü olarak değerlendirilebilecek bu eserlerin dıĢında sevgilinin güzellik unsurlarından müteĢekkil mesneviler de vardır. tâcîzâde cafer Çelebi hevesnâme‟sinin – . beyitleri arasında sevgilinin güzelliğiyle alakalı unsurdan bahseder (atay , – ). konumuzla alakalı yazılmıĢ olan hassân‟ın farsça‟dan tercüme ettiği mihr ü müĢterî ( ) , kara fâzlî‟nin gül ü bülbül‟ü ( ) unsura değinen mesnevilerdir. manastırlı celâl‟in hüsn-i yûsuf adlı eseri her biri sevgilinin güzellik unsurları üzerine yazılmıĢ gazelden oluĢmaktadır. eser sevgilinin güzelliği ile ilgili unsurdan bahseder (aksoyak , ). celâl, konuların tertip sırasında enîsü‟l-uĢĢâk‟ı esas almıĢtır. hüsn-i yusuf‟u diğer mesnevilerden farklı kılan yönü konunun iĢlendiği bölümde mesnevi nazım biçimi yerine gazel yerleĢtirilmesidir (aksoyak , - ). bahsettiğimiz bu eserlerdeki güzellik unsurlarını Ġ. hakkı aksoyak tablo halinde göstermiĢtir. tâcizâde cafer Çelebi‟nin hevesnâmesi üzerinde çalıĢma yapan hakan atay, sevgilinin güzellik unsurlarını bir tablo ile belirlemiĢ. bu çalıĢmaya Ġ. hakkı aksoyak ġerafeddin râmî‟nin enisüsü‟l-uĢĢâk ve manastırlı celâl‟in hüsn-i yusuf‟undaki güzellik unsurlarını eklemiĢtir. biz de yüksek lisans tezimizde bu yapılan çalıĢmalara muhittin eliaçık‟ın bavyera devlet kütüphanesi‟nde bulduğu güzellik unsurlarıyla ilgili risaleyi eklemiĢtik. daha sonra eliaçık, hüsam bin mustafa el-belgradî‟ye ait olduğu düĢünülen risalenin miftâhü‟t-teĢbih‟ten intihal olma ihtimalinin bulunduğunu açıklamıĢtır (eliaçık , – ). bu unsurlar şunlardır: saç, alın, kaş, göz, kirpik, yüz, ayva tüyü, ben, dudak, diş, ağız, çene, boyun, göğüs, kol, parmak, boy, bel, baldır. hüsn ü cemal, ışk, muy, cebin, ebrû, çeşm, müjgân, gamze, ruhsâr, bînî, hat, hal, leb, dendân, dehân, zenehdân, gerden, ber ü pistân, sâid ü dest ü bâzû, engüşt ü benân, kadd ü kâmet, miyân, sâk, beden ü endâm, zât-ı mahbûb, kelâm. mûy, gûş, cebîn, ebrû, çeşm, bînî, müje, rûy, hat, hâl, leb, dendân, zenehdân, gerden, sîne, engüşt, sâid, kadd, miyân, sâk. hüsn ü cemâl, ışk u hâl, kâkül ü zülf, alın, kulak, kaş göz, kirpik, gamze, yüz, burun, hat, kara ben, dudak, dendân, ağız, dil, enek, boyun, göğüs, bilek, parmak, boy, bil, incik, mecmû-ı azâ, zât-ı mahbûb, söz. kâmet, mû, cebîn, ebrû, çeşm, müjgân, zülf, gûş, ârız, hâl, ruhsâr, bînî, dehen, leb, dendân, zebân, zekân, gabgab, gerden, sîne, bâzû, sâid, kef, puşt-ı dest, asâbi, nâhunhâ, batn, nâf, miyân, pehlû, rân, sâk, kadem. saç, kaş, göz, bînî, yanak, gûş, leb, dehân, dendân, dil, zenehdân, gabgab, gerden, dûş, bâzû, bilek, dest ü sâid, el, parmak, dırnak, ber, pehlû, şikem, nâf, pûşt, kad, bil. zülf, kâmet, pişânî, ebrû, çeşm, gamze, müjgân, bînî, ruhsâr, hâl, gûş, leb, dehân, zebân, dendân, gabgab, zekân, gerden, bâzû, sâid, dest, engüşt, nâhun, sine, miyân, nâf, sâk, pây . kâkül, zülf, cebîn, ebrû, çeşm, müje, gamze, ârız, ruh, gûş, leb, dehen, zekân, gabgab, gerden, sîne, miyân, dest, said, pây, ser ü pây, kâmet. risaleye dair ayrıntılı bilgi için bkz. eliaçık , – ; eliaçık , – sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer sevgilinin güzellik unsurları etrafında oluĢturulmuĢ Ģiir mecmuaları da vardır (gürbüz , ). xvi. yüzyılda kâbilî‟ye ait olduğu sanılan sultân-ı hûbâna münâsib eĢ‟ar ile xviii. yüzyılda lâzikîzade feyzullah nâfiz‟in letâifü‟l-hayâl adlı eseri bu geleneğe güzel bir örnektir. yukarıda saydığımız eserlerin tümü genelde sevgilinin fiziksel özelliklerini ağırlıklı olarak iĢlemiĢtir. aralarındaki farklar söz, aĢk ve iĢve gibi hususiyetlere değinme noktasındadır. bu eserlere ve yapılan divan tahlili çalıĢmalarına baktığımızda üzerinde en fazla durulan unsurun saç olduğu görülür. bundan dolayı yapılan pek çok çalıĢmaya önce saç ve saça ait benzetmeler verilerek baĢlanmıĢtır. mu‟îdî, güzellik mülkünün baĢkanı mûydur. onun üstünde nesne olmadığı için ilk önce saçın sıfatları üzerinde durduğunu söylüyor (erünsal , ). ÇalıĢmalarda genel olarak Ģekil, renk ve koku yönünden saç ele alınmıĢ, birtakım benzetme ve mecazlardan hareketle saçın Ģiirde nasıl kullanıldığı üzerinde durulmuĢtur; fakat saçın âĢık üzerindeki etkisini belirten ifade unsurları toplu olarak değerlendirilmemiĢtir. makalemizde bunlar da göz önünde bulundurularak saçın âĢık üzerindeki etkisi ve Ģiirdeki yansıması üzerinde durulacaktır. klasik türk Ģiirinde sevgili için olmazsa olmaz unsurların baĢında saç gelmektedir. sevgilinin güzelliğini büyük ölçüde sağlayan saçtır. saç olmazsa güzellik olmaz. saç insan vücudunun en üst noktasında bulunur ve ilk göze çarpan unsurdur. bu bakımdan pek çok yönleriyle Ģiirlerde ele alınmıĢtır. saçı anlatmak için kullanılan sıfatlar çok çeĢitli ve boldur. klasik edebiyatımızda saç; zülf, kâkül, turra, gîsû, mû(y), külâle, perçem gibi yakın anlamlar ihtiva eden kelimelerle ifade edilir. râmî, sevgilinin gül bahçesini andıran yanağına halkalanmıĢ yatan yılanı (râmî , ); mu‟îdî ise dolunayı örten bulutu andıran saça zülf dendiğini ifade eder (erünsal , ). zülf, „gece yarısı‟ anlamına gelmekte olup, saçın tek parçasına verilen isimdir . zamanla saçın anlamını ihtiva etmiĢtir. zülf dendiği vakit doğrudan saç akla gelmektedir (arı , ). ġemseddin sâmî zülf için mahbube saçı, alelhusus yüzün iki tarafında sarkan saç bölükleri; zülfe için de bazı Ģeylerin tepesindeki püskülcük, bayrak olarak açıklama yapmaktadır (ġemseddin sâmî , ). kâkül alna dökülen, alında halkalanan saç; gîsû omuza dökülen saç, uzun saç, kadınların arkalarında saldıkları örgülü, örgüsüz uzun saç; mû(y) kıl, saçın teli, saç; perçem alna dökülen halkalanan saç, tepede bırakılan saç, püskül; turra alna dökülen saç, lülelenmiĢ saç; külâle kıvırcık saç, kâkül, çiçek destesi anlamlarına gelmektedir (Ġpekten , ). bu unsurların saçın değiĢik yönlerini anlatmak için kullanıldıkları görülmektedir. her biri saçın farklı bir görünüĢüne iĢaret etmiĢ ve zamanla saçın belirli Ģekillerinin ismi olmuĢtur. ġairlerin bu kavramların tamamını Ģiirlerinde kullanmaları bunlar arasındaki farklılıkları bildiklerini gösterir. bazı beyitlerde bunların karĢılaĢtırıldığını bile görürüz. ġeyh gâlib turrayı zülfün yanında eğitim gören bir çocuğa benzetir: mektebde ağzı misk kokar tıfl-ı turre kim zülfünden ilm-i sihr içün âheng-i çîn eder ġeyh gâlib, . g./ ġairler tarafından üzerinde en çok durulan ve en beğenilen saç Ģekli zülftür. ġiirlerde o kadar çok kullanılmıĢtır ki artık saç dendiği vakit zülf akla gelir olmuĢtur. yaptığımız küçük bir araĢtırmayla Ģu sonuca ulaĢtık: ġeyhî zülf kelimesini divanında , fuzûlî , bâkî , nef‟î , nâilî , ayrıntılı bilgi için bkz. gürbüz , – . ayrıntılı bilgi için bkz. demir , – . söz konusu çalışmalar için bkz. Çavuşoğlu, : - ; kurnaz, : - ; sefercioğlu , : - ; tarlan, : - ; tolasa, : - . zülf ve şekilleri hakkında ayrıntılı bilgi için bkz. tanyıldız , – ; gökhan , - . metin içinde kullanılan kısaltmalar şu şekildedir: g.: gazel, k.: kaside, kt.: kıta, msmt.: musammat, tcb.: terci bend, s.: sayfa. kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer nedîm , ġeyh gâlib , enderunlu vâsıf defa kullanmıĢtır. diğer unsurlarla kıyaslandığında zülfün çok önde olduğu görülür. ġeyhî: perçem ( ), turra ( ), mû(y) ( ); fuzûlî: mû(y) ( ), kâkül ( ), gîsû ( ), turra ( ); bâkî: turra ( ), kâkül ( ), mû(y) ( ), gîsû ( ), külâle ( ); nef‟î: turra ( ), gîsû ( ), kâkül ( ), perçem ( ), mû(y) ( ); nâilî: turra ( ), kâkül ( ), gîsû ( ), mû(y) ( ), külâle ( ); nedîm: kâkül ( ), gîsû ( ), turra ( ), mû(y) ( ), perçem ( ); ġeyh gâlib: perçem ( ), kâkül ( ), turra ( ), gîsû ( ), mû(y) ( ); enderunlu vâsıf: gîsû ( ), perçem ( ), turra ( ), kâkül ( ), mu(y) ( ), külâle ( ) olmak üzere divanlarında saçın değiĢik Ģekillerini kullanmıĢlardır . görüldüğü gibi zülf dendiği vakit bütün bir ihtiĢamıyla saçın anlaĢılması; Ģairlerin Ģiirlerinde en fazla ona yer vermelerindendir. sevgiliye ait diğer güzellik unsurları arasında da saç Ģiirlere en çok konu olandır. tahlil çalıĢmaları arttıkça Ģairlerin sevgiliye bakıĢ açıları daha da netlik kazanacaktır. her Ģair sevgiliyi aynı gözle mi görmüĢtür, yoğunlaĢma noktaları nelerdir gibi sorulara yanıt verebilmek ve üslup farklarını ortaya koyabilmek için tahlil çalıĢmalarının yapılması gereklidir. saça ait benzetmeleri genel olarak dört baĢlıkta toplamak mümkündür; fakat bunlar arasında kesin bir ayrım yapmak zordur. bir benzetmede Ģekil, renk, koku ve eylem unsurlarının tamamı olabileceği gibi iki veya üç yönden de benzerlikler düĢünülebilir. bu sebeple en kuvvetli yön göz önüne alınarak benzetmeler tasnif edilmeye çalıĢılmıĢtır. edebiyatımızda Ģairlerin saçla ilgili kullandıkları benzetme ve tasavvurlardan kısaca bahsetmekte fayda var. saça ait benzetmelerde Ģekle ait hususiyetlerin ön planda olduğu görülür. ġekil yönüyle saç: Ġp (resen, riĢte, risman, silk, Ģikâl), bem, deste, fitil, târ, tel, zincir, silsile (müselsel), ca‟d, pîç (pîçtâb), dâm, kemend, dâr, urgan, ağ, olta, bend, halka, asa, beste, çember, çengel, girih, ham, hamîde, kıl, kullâb, lenger, nısf daire, pençe, ukde, girdap, sümbül (sümbül bahçesi, tarh), üzüm salkımı, bîd (söğüt), reyhan, Ģebbû(y), tûbâ, berg, gül bahçesi, leylakzâr, ĢimĢâd, yılan (mâr, ef‟î, su‟bân), ejderhâ, timsah, akrep, aba, kâbe örtüsü, seccâde, nikâb, rikâb, perde, hicâb, atlas, destâr, harîr, kâle (kumaĢ), sebz-pûĢîde, bâl ü per, abnus, câme (elbise), hırka, zırh, dâmen (etek), fûtâ ( peĢtamal), dümdâr, semmur (kürk), âb-ı revan, yol, tûl-i emel, uzun ömr, hikâye, kıssa, efkâr, cadde-i teselsül, dıraz, güneĢ ıĢıkları, tâb, zer-hal, mahz-ı can, mutarra, revnak, bağban, nakkaĢ (nakĢ), mıstar (cetvel), cedvel çeken, perdedâr, müderris, sultan, haberci, server, tıfl, ziver, timur, niĢancı, sayyâd, ârâyiĢ-i ruhsâr, dest-i niyâz, dest-i tedâvül, çevgan, tespih, hamayil, rahle, kandil, âvize, fitil, râyet, tuğ, perçem, mızrak (nize), sancak, cim, dal, lâm, merdiven, nal, üzengi, kılıf, dütâ, kat kat, ibriĢim, nigûn bürîde (kesilmiĢ), kalem, kafiye, lika tuğra, yazı (hat), nüsha, sah, lefîf, mahĢer, halvetgah, mabed, meva, meĢar, nüzhetgeh, fitne, belâ, ahd, müĢkil, çeng, bulut (ebr), gölge (sâye), dûd (duman, duhân), dalga (mevc), pas (jeng), hâle, cârub (süpürge), çalı çırpı, göz, el, avuç, yara, ev, kafes, yuva (aĢiyan), çadır (çetr, hayme), gölgelik, pencere, kilit, anahtar, kuĢ, Ģehbaz, hümâ, karga, kırlangıç, tavus, Ģeh-per, kanat, ġebdîz (hüsrev‟in atı ), mur, perrin, Ģahin, güvercin, menzil, memleket, Çin, ordu, çeri, kafile, tabur, zünnar, haç (salîb), micmer, papaz (kıssîs) gibi kelimelerle nitelendirilmiĢtir. saç çoğunlukla siyah olarak ele alınır. bu siyahlıktan hareketle aya ve güneĢe benzeyen yüz arasında bir tezat yapılır. saçın siyahlıkla ilgili pek çok kelimeyle tavsif edildiği görülür. ġairlere göre siyahtan baĢka daha güzel bir renk yoktur. renk bakımından: gece (leyl, leylâ Ģeb, Ģâm, akĢam), ûdî, duman (dûd, duhân), sâye ( gölge, gölgelik), sebzgûn semâ, ebr (bulut, sehâb), karga (gurâb), hindû, kara bağ, karaman, frengistan, kâfiristan, siyah (kara), tîre, deycûr, papaz ( kıssîs), midâd, sevâd, zerd, sevda, harf, hat, göz bebeği, zindan, zulmet, belâ, kâfir, küfr vb. kelimeler kullanılmıĢtır. saç için siyah renk vazgeçilmez bir özellik olsa da zaman zaman sarı saçtan bahseden Ģairler de olmuĢtur. divan Ģairinin dünyasında güzel için sarıĢınlık âdeta yasak renktir. ġairler, sarı rengi solgun, bitkin ve hastalıklı yüzlerini ifade etmek için kullanmıĢlardır (köksal , ). . yüzyıl Ģairlerinde “sarı bu konuda ayrıntılı bilgi için bkz. Şahin , – sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer saç”a daha fazla tesadüf ediyoruz. divan Ģiirine pek çok yenilikler getiren nedîm‟de bunun en güzel örneklerini görmek mümkündür. sevgilinin saçı ve güneĢ arasında bir benzerlik kurmuĢtur: hurĢîd pençesin mi takınmıĢ cebînine ol zülf-i zerdden dökülen terler midir nedîm, g./ zerd kelimesiyle renk ve parlaklığından dolayı ilgi kurulur. kelimenin sarı, halka halka örülmüĢ savaĢçı zırhı (devellioğlu , ) anlamlarını ihtiva etmesi de düĢünülerek Ģiirlerde kullanıldığı görülür. zer-hal ve sırma kelimeleri de kullanılmıĢtır. ġairler; saçın parlaklığından da bahsetmiĢler ve tâb, harîr, zerd, garra, ahter-i elmas gibi kelimelerle saçı anmıĢlardır. sevgilinin uzuvları ile memleketler arasında tevriye yoluyla iliĢki kurulması sıkça karĢılaĢılan bir durumdur. bunlar arasında nadir görülen bir benzetme de saruhan-saç iliĢkisidir (köksal , ). ġairler tarafından ağarmıĢ, beyazlamıĢ saçtan da bahsedilmiĢtir. bu tür ifadelerde sevgili değil âĢıkların kendi durumları anlatılmaktadır. yaĢlılığın ve ömrün sonuna gelindiğinin veya çok fazla çekilen üzüntü ve ıstırabın bir neticesi olarak kullanılmıĢtır (Öztoprak , ). saçın kokusu ile ilgili olarak doğrudan koku anlamını ihtiva eden bû(y), nükhet, Ģemîm, nâfe, nefhâ, râyiha kelimeleri ile abîr, gâliye, menekĢe, gül, karanfil, misk (müĢg), nesîm, reyhân, semen, yasemen, sümbül, Ģeb-bû (Ģebboy), tîb, amber, micmer, ıtr, attâr (dükkân-ı attâr, tabla-i attâr), Çin, hıta (hatâ), hoten (huten), tibet, müĢg-i buhâra, tâtâr vb. kelimeler kullanılır. saydığımız yer isimleri misk ahusunun yaĢadığı bölgeler olmasından dolayı sıkça zikredilir. saçın kokusuyla alakalı pek çok benzetme yapılır; ama onun kokusu bu sayılanların hepsinden üstündür. edebiyatımızdaki önemli bazı Ģairlerin saç ile ilgili en fazla kullandıkları benzetme unsurlarına kısaca değinmekte fayda var. ġeyhî divanı‟nda: zülf ( ), müĢg-misk ( ), sünbül ( ), çîn ( ), anber ( ), silsile ( ), benefĢe ( ), dâm ( ), kemend ( ), mu‟attar ( ); fuzûlî: zülf ( ), perîĢân ( ), sünbül ( ), mû(y) ( ), kâkül ( ), târ ( ), müĢg ( ), zincir ( ), anber ( ), hâm ( ); bâkî: zülf ( ), sünbül ( ), müĢg-misk ( ), turra ( ), bend ( ), kâkül ( ), anber ( ), siyah ( ), kemend ( ), mû(y) ( ); nef‟î: zülf ( ), turra ( ), hâm ( ), gîsû ( ), sünbül ( ), perîĢân ( ), kâkül ( ), belâ ( ), fitne ( ); nâilî: zülf ( ), turra ( ), kâkül ( ), dâm ( ), sünbül ( ), tâb ( ), hâm ( ), müĢg ( ), bûy ( ), perîĢân ( ); nedîm: zülf ( ), sünbül ( ), kâkül ( ), gîsû ( ), turra ( ), çîn ( ), mû(y) ( ), siyah ( ), hâm ( ), zincir ( ); ġeyh gâlib: zülf ( ), perçem ( ), kâkül ( ), sünbül ( ), siyah ( ), turra ( ), küfr-kâfir ( ), gîsû ( ), pîç ( ), müĢg-misk ( ); enderunlu vâsıf: zülf ( ), sünbül ( ), gîsû ( ), Ģeb-bû-Ģebboy ( ), perçem ( ), turra ( ), kâkül ( ), siyah ( ), perîĢân ( ), Ģeb ( ) benzetmelerini ağırlıklı olarak kullanmıĢtır. ġairlerin sevgiliye bakıĢ açılarını, sözcük ve duygu dünyalarını anlayabilmek için bu tür çalıĢmaların yapılması lazım. biz, edebiyatımızdaki önde gelen bazı Ģairlerin divanlarından hareketle böyle bir çalıĢma yapmayı denedik. ÇalıĢmaların sadece divanlarla sınırlı kalmayıp Ģairin bütün eserlerini kapsaması gerekmektedir. ancak, o zaman Ģairle ilgili doyurucu sonuçlara ulaĢılabilir. bu konuda ayrıntılı bilgi için bkz. köksal , – . Çalışmada, şairlere ait farklı söyleyişlere değinilmektedir. sarı saç ve mavi göz ile ilgili örnekler sunulmuştur. burada sadece ilk on benzetmeye değinilmiştir. bu konu yüksek lisans tezimizde ayrıntılı bir şekilde ele alınmıştır. tezde, bahsi geçen şairlerin saçı tavsif etmek için kullandıkları kelimeler ve kullanım oranları verilmiştir. genel hatlarıyla şairlerin saça bakış açısı ve sevgili algısı gözler önüne serilmeye çalışılmıştır. büyük bir titizlikle divanlar taranmış ve konumuzla alakalı olan beyitler tespit edilmiştir. verilen sayısal değerlerde, sonuçları çok fazla değiştirmeyecek ufak hatalar yapılmış olabilir. bu ve buna benzer yanlışlar için siz değerli araştırmacıların hoşgörüsüne sığındığımı bir kez daha ifade etmek isterim. kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer saçın ÂĢık Üzerindeki etkisi saç için sevgilinin güzellik unsurlarından en üstün tutulanı, güzellik ülkesinin baĢta bulunan padiĢahı ve sevgilinin âĢığa en çok tesir eden güzellik unsuru olduğunu vurgulamıĢtık. o, dağınık, karıĢık, kıvırcık ve örülmüĢ Ģekli, uzunluğu, siyah rengi ve kokusuyla birçok unsurla benzerlik gösterir (pala , ). saça ait benzetme ve mecazlar tasnif edilirken Ģekil, renk ve koku hususiyetlerinin dıĢında saçın âĢık üzerinde yaptığı etkiyi ifade eden kelimelerle de anıldığı görülür. klasik Ģiirde sevgilinin âĢığa veya âĢıklara karĢı olan tavrında en büyük yardımcısı olarak saçı görmek mümkündür. saç; rengi, kokusu ve Ģekliyle âĢıklar üzerinde çok büyük etkiye sahiptir. ġairler bu benzetmelerin dıĢında onun yarattığı etkiyi ifade etmek için farklı kelimelerle de saçı anmıĢlardır. anılan bu kelimelerin bazen saçın görünümü ve rengiyle ilgili çağrıĢımlar uyandırdığı görülür. bilindiği gibi klasik Ģiirin en büyük hususiyetlerinden birisi de çağrıĢım dünyasının zengin olmasıdır. ÂĢık üzerindeki etkisini ortaya koyan teĢbih, mecaz ve hayalleri Ģu Ģekilde inceleyebiliriz: . belâ, âfet, fettan, fitne (ceyş-i fitne) bu benzetmelerde renk özelliği de düĢünülmüĢtür. kargaĢa sonunda bela kaçınılmazdır. saçın rengi ve çokluğu sebebiyle kesret oluĢu, fitne, bela, âfet, fettan gibi unsurların kesretle ilgisini de çağrıĢtıracak Ģekilde Ģiirde kullanıldığı görülür. ġeyhî, sevgilinin kıvrımlı saçlarını boynuna dolamasını belâ tuzağına yakalanmaya benzetir. klasik Ģiirde âĢıkların gönüllerinin sevgilinin saçına asılıp kalması, üzerinde çok durulan tasavvurlardandır. ġeyhî, saçın sevdasından dolayı âĢığın çılgına döndüğünü ve derbeder olduğunu ifade ediyor: müselsel zülfü boynuma salaldan bend-i sevdâyı belâ dâmında ser-gerdân benim rüsvâ vü Ģeydâyî ġeyhî, . g./ saçlar, âĢıklar arasında kargaĢa çıkarır, ortalığı karıĢtırır, kıyametler koparır. nedîm, sevgilinin kıvrımlı zülfünde fitnenin bağlanmıĢ olduğunu söyler: dedim ki ey ham-ı zülfünde fitne der-fitrak kenâr-ı nevk-i müjende kiriĢme der-çengal nedîm, . k./ yine nef‟î bir Ģiirinde sevgilinin saçlarında fitne gizlenmiĢ olmasaydı gönlün fettan kâküle bağlanmayacağını söyler. ÂĢığın gönlünde fitne ve kargaĢaya sebep olduğu için fettandır: olmazdı dil o kâkül-i fettâna giriftâr bin fitne nihân olmasa zîr-i külehinde nef‟î, . g./ . perişan, pejmürde, harap, tarumar, derhem, jülide, keşmekeş, şikeste, müzmahil, aşüfte, âşık, âvâre, serkeş, derviş saçın bu unsurlarla anılması, çoğunlukla âĢığın gönlünün dağınıklığı ile alakalıdır. ÂĢığın parça parça olmuĢ gönlü, sevgilinin saçlarına takılı olarak nitelendirilir. sevgilinin saçlarını toplaması ve düzeltmesi âĢıkların parçalanmıĢ gönüllerini bir araya getirecektir. hem sevgilinin saçları hem de âĢıkların gönülleri dağınık ve periĢandır. sevgilinin dağınık saçlarını görünce âĢıkların eli ayağı sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer tutulur. nâilî, sevgilinin dağınık saçını görmeden ölen âĢığa bir avuç kabir toprağının kıyamete kadar ağır bir yük olacağını belirtir: eger olmazsa perîĢânî-i zülfün rûzî haĢre-dek bâr-ı girândır bir avuç hâk bana nâilî, . g./ ġeyhî, sevgilinin aya benzeyen yüzüne inmiĢ olan dağınık saçları ayın yüzeyindeki tozlara benzetir: hasretiyle özünün yüzünü jeng eyledi ay gördü kim gün yüzüne zülf-i perîĢân dökülür ġeyhî, . g./ saçlar dağınıklığı ve karmakarıĢık Ģekli dolayısıyla pejmürde olarak nitelendirilir. ÂĢıkların gönlü her zaman dağınık ve periĢandır. bu dağınıklık âĢıkların uykusuna bile yansır. onlar sevgilinin hasretinden uyuyamazlar. onların uykularını kaçıran diğer bir sebep de kıskançlıktır. nedîm, âĢıkların uykusu ile sevgilinin saçları arasındaki iliĢkiyi Ģu Ģekilde ifade ediyor: saçı fütâdesinin hâbı gibi pejmürde nigâhı âĢıkının hâtırı gibi efgâr nedîm, . k./ ÂĢık bir cambazdır. o, çektiği acıdan dolayı incelip kıl kadar olur nice çemberlerden geçer; fakat sevgilinin saçlarının aĢkından geçemez. geçmelü oldı gönül za‟f ile çenberlerden ne hevâdur bu ki ol zülf-i dü-tâdan geçemez necâtî, . g./ sevgilinin kıl kadar ince olan saçları, âĢıkların kıl kadar incelip zayıflamasına sebep olur. güzelin saçının arzusuyla âĢık kendinden geçer, Ģuuru kaybolur. o, saç için canını vermekten çekinmez. bak ne çenberlerden eylermiĢ güzer cân-bâz-ı aĢk halka halka bend-i zülfü târümâr olsun da gör ġeyh gâlib, . kt./ sevgilinin saçlarının âĢıklar üzerinde bıraktığı etkiyi ve sevgilinin saçlarının yapısını anlatmak için, çıldırırcasına seven, bu yüzden periĢan bir halde, azgın ve baĢtan çıkmıĢ deli gibi olan anlamlarına gelen aĢüfte, serkeĢ, sevda, âĢık vb. kelimelerin kullanıldığı görülür. n‟ola ta‟yin etse zabt-ı mülk-i hüsnü gamzeye zülfü bir âĢüfte-i ser-der-hevâdır n‟eylesin nef‟î. . g./ kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer saçlar sevgilinin yanağını kapatır ve bu durum âĢık için dayanılmaz bir acı kaynağıdır. ÂĢık saçlardan dolayı güzelin cemalini göremez. hem sevgilinin yüzünü görmek hem de sevgilinin saçlarına bağlanmak âĢıklar tarafından arzu edilen bir durumdur. fuzûlî‟nin aĢağıdaki beytinde zülfün sevdasının âĢığı ayaklar altına aldığından bahsedilir: mihr salmazsan bana rahm eylemezsen bunca kim sâye tek sevdâ-yi zülfün pây-mâl eyler beni fuzûlî, . g./ saçın dağınıklığını duymayan bilmeyen kalmamıĢtır. fuzûlî saçı divane bir âĢığa benzetmiĢtir: ruhun devrinde bir divânedir sevdâlı zülfün kim perîĢânlıkdan olmuĢ ben kimi meĢhûru devrânın fuzûlî, . g./ . tarrar, mekr, kec-bâz, kec ü mec, aşub u yağma ÂĢıkların gönlünü çalması nedeniyle saçlar yankesici ve hırsız olarak nitelendirilir. saçlar gönül hırsızıdır. fuzûlî‟nin derd çekmiĢ baĢım ol hâl-i siyeh kurbânı tâb görmüĢ tenim ol turra-i tarrâra fidâ fuzûlî, g./ dediği beytinde tuzak olarak nitelendirilen sevgilinin benleri ile hileci olarak değerlendirilen saçların âĢığı avlaması dile getiriliyor. ÂĢık bu durumdan memnundur. bilindiği gibi benlerin gönül kuĢunu avlamaya çalıĢan tuzağa konmuĢ yem olarak tasavvuru divan Ģiirinde çokça dile getirilir. ÂĢıklar üzerindeki etkisi ve yarattığı kargaĢa dolayısıyla saçlar, hilekâr olarak vasıflandırılır. sevgilinin saçları âĢıkların gönlünü hile ve oyunlarla ele geçirir. saçların bu hilede yalnız olmadığını görüyoruz, sevgilinin diğer unsurları da buna yardımcı olmaktadır. bâkî, bunu Ģu Ģekilde ifade ediyor: alınmazdı gönül yâr olmayaydı ser-i zülfün gibi kec-bâze ger ruh bâkî, . g./ kargaĢalık yaratmak sevgilinin en önemli vasfıdır. ġeyh gâlib söz söylemenin amacı mana, turranın amacı ise kargaĢa yaratmaktır diyerek sevgilinin saçlarının âĢıklar üzerindeki etkisini Ģöyle açıklıyor: turreden âĢûb u yağmadır garaz lafzdan zîrâ ki ma‟nâdır garaz ġeyh gâlib, . g./ saçlar Ģekil itibariyle eğri ve çarpık olarak telâkki edilir. ÂĢıkların gönüllerini altüst eder. sevgilinin güzellik unsurlarından kaĢ, ayva tüyleri, gamze, kirpik de saç gibi gönüllerde kargaĢaya neden olur. bu, âĢıklar tarafından anlaĢılmayan ve hesap edilemeyen bir durumdur. sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer hat-ı fireng gibi zülf ü ebruvân kec ü mec ne anlanır rakam-ı mekri ne hisâbâ gelir. ġeyh gâlib, . g./ . câdû, efsûn, sâhir, hârut, bî-din, kâfir, kıssîs (papaz) ÂĢıklar üzerindeki etkisi ve büyücülük özelliğinden dolayı saçların bu benzetmelere konu olduğunu görüyoruz. divan edebiyatında sevgilinin gözü, gamzesi, saçı ve ayva tüyleri cadılık özelliklerine sahiptir. cadıların kötülük, zulüm, kan dökme özelliği de vardır (pala , ). saçların cadı ve büyücü olarak ele alınmasında sevgilinin saçının her bir kılına binlerce gönlü bağlayabilecek kabiliyete sahip olması ve büyücülükte büyü yapılacak kiĢinin saçının kullanılması etkilidir (deniz , ). cadıların doğaüstü güçleri olduğuna inanılır. bâkî, sevgilinin suyu andıran yanağı üzerinde duran saçlarını bu yüzden cadıya benzetir: görüp zülfün „izârun üzre bildüm mukarrer batmaz imiĢ suya câdû bâkî, . g./ yanağın güneĢ olarak ele alınması ve güneĢe yaklaĢmanın, onu tutmanın imkânsız olmasına rağmen saçın yanak üzerine inmesi, ona değmesi saçın, sâhir olarak vasıflandırılmasına da sebep olur. (ÇavuĢoğlu , ) saçlar büyü, sihir gibi unsurlarla ve hz. mûsâ‟nın yılan olabilen asasını hatırlatacak biçimde Ģekil ve durum yönüyle Ģiirlerde sıkça kullanılmıĢtır. nitekim fuzûlî sevgilinin saçlarını büyülü bir yılan olarak değerlendirir: zikr-i lebinde zülfüne cân oldu destres anun kimi kim okuyup efsûn yılan tutar fuzûlî, . g./ ġeyhî, saçı hz. mûsâ‟nın asasına benzetir. saçların âĢıklar üzerindeki sihirli etkisinden dolayı bu tarz benzetmeler yapılmıĢtır: Ġ‟câza saçın asâ-yı mûsâ Ġhyâda lebin mesîh-i meryem ġeyhî, . msmt./ ÂĢıklar üzerindeki etkisi ve siyahlık faktörü de göz önünde bulundurularak saçların kâfir, dinsiz ve papaz gibi kelimelerle tavsif edildiği görülür. zülfün hayali gönülden gitmez; çünkü kâfirin yaptığı bina sağlam olur. yüz üzerindeki ayva tüylerini zülf örter. ayva tüyleri kur‟an yazısı olarak değerlendirildiğinde, zülfün bunu kapatması kâfirliğe delalet eder. zülfün ucunda gönül barınamaz çünkü zülf diğer unsurlarla birleĢince kâfir çoğalır (ÇavuĢoğlu , ). nedîm; benleri, saçları ve gözleri kâfir olarak nitelemiĢ ve baĢtan baĢa sevgilinin bütün güzelliklerini kâfiristan olarak değerlendirmiĢtir: hâl kâfir zülf kâfir çeĢm kâfir el-amân ser-be-ser iklîm-i hüsnün kâfiristân oldu hep nedîm, . g./ kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer leb-i cân-bahĢına ser-dâde-i îkân Ġsî kâkülü büt-kede-i perçeminin kıssîsi ġeyh gâlib, . g./ arapçadaki anlamı bir Ģeyin üstünü örtmek olan küfr sözcüğünün diğer bir anlamı da karanlıktır. klasik türk Ģiirinde saç küfr, yüz iman olarak kesret-vahdet ikileminde değerlendirilmiĢtir. ÂĢık çoğu zaman kesrete bağlanıp kalır ve vahdete ulaĢamaz. bâkî, sevgilinin dinsiz olan saçları ve cadı olan gamzesinden herkesin sakınması gerektiğini söylüyor. bunların kimseye ulaĢmamasını diliyor: kimseye uymasun ulaĢmasun allâh allâh zülf-i bî-dîn ile ol gamze-i câdû begler bâkî, . msmt./ allah tarafından hârut‟a büyü ve sihir ilmi verilmiĢtir. verilen bu ilmi kötüye kullandığı için bâbil‟de bir kuyuya saçlarından asılarak kıyamete kadar cezalandırılmıĢtır. daha çok arkadaĢı mârut ile birlikte anılır. ahmed paĢa‟nın ġol çeh-i bâbil‟deki hârût kim vasf itdiler bu zenâhdânundaki zülf-i perîĢân olmasun ahmed paĢa, .g./ dediği beytinde sevgilinin çene çukuru bâbil kuyusuna benzetilmiĢ ve hârut‟un bu kuyuda saçlarından asılarak sallandırılmasına telmih yapılarak zülf-hârut iliĢkisi üzerinde durulmuĢtur (deniz , ). . dâm, dâr, girdâp, kemend (bend, olta, ağ, peyvend), ukde, kafes, zindan, sayyâd, Ģahbâz, Ģahin, hümâ, yılan (mâr, ef‟î, su‟bân, ejderhâ), timsah, akrep, zehr saçlar; yakalama, tutma, bağlama, avlama ve hapsetme anlamlarına gelen unsurlarla sıkça anılır. bu tür benzetmelerde Ģekle ait hususiyetlerin de ön planda olduğu görülür. saçla ilgili ip, dâm, kement, dâr, urgan, ağ, olta, bend, halka, asa, beste, çember, çengel, halhal, kullâb, lenger, nısf daire, pençe, ukde vb. kelimelere ait sayısız tasavvur, teĢbih ve mecaz pek çok beyitte karĢımıza çıkar. saçların uçlarının kıvrımlı ve halka halinde olması veya dolaĢık olduğundaki düğümleri bu benzetmelerin kaynağını oluĢturur. bu kıvrımlardan hareketle âĢığın durumuna göndermeler yapılır. bu özelliklerinden dolayı âĢıklar hep sevgilinin saçlarına takılıp kalır. saç âĢığı yaĢlandırır, yüzünü kırıĢtırır. sevgilinin saçları âĢıklar için birer tuzaktır. ÂĢıkların gönlü sevgilinin saçının tuzağına yakalanır. ÂĢığın istediği sevgiliye bağlı olmaktır. ÂĢıkların gönülleri sevgilinin saçına asılı olarak tasavvur edilir. zülf dâm olarak ele alınınca benler, tuzak içindeki daneye, gönül de kuĢa benzetilir (sefercioğlu , ). ġeyhî, can kuĢunun ne kadar yüksekte uçarsa uçsun güzelin saçlarına bağlanmaktan kurtulamayacağını söylüyor: cân kuĢu yer felekte uçarsa melek-misâl boynuna dâm-ı zülfünü salsan irer yeter ġeyhî, . g./ sevgilinin saçlarının dâr, kemend gibi unsurlarla anılmasında en önemli husus, asılma, can vermedir. sevgilinin bu unsurlara benzetilen saçında can veren, âĢığın gönlü ve canıdır. gönüllerin sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer aĢığın saçına asılmıĢ olarak kullanılması sıkça yapılan tasavvurlardandır (sefercioğlu , ). ġeyh gâlib hallâc-ı mansûr‟a telmihen güzelin saçlarına değmenin asılmaya neden olacağını vurguluyor: değmesin ellerin kâkül-i dildâra sakın sonra mansûr gibi çıkman olur dâra sakın ġeyh gâlib, . tcb./ saçların düğüm olarak ele alınması Ģekil ve durum benzerliğine dayanır. düğüm bir Ģeyi sıkıca bağlamaya yarar. ÂĢıkların gönlünün bağlanmasıyla ilgi kurulur. ayrıca düğümün çözülecek mesele olması, saçın çözülmesi zor bir mesele olarak ele alınmasına sebep olur (sefercioğlu , ). yine Ģekli ve âĢıkları çekmesi nedeniyle saçlar bir girdaptır. hem cârda sûziĢ-i hüsn hem ıztırâb-ı ebrû hem dilde ukde-i zülf hem pîç ü tâb-ı ebrû nâilî, . g./ dile çîn-i cebinin zülf-i pürtâbı unutturdu hurûĢ-ı mevc-i hayret bîm-i girdâbı unutdurdu nâilî, . g./ sevgilinin saçları âĢıkların gönüllerini hapseden bir kafese benzetilir. gönül kuĢu burada kalır. saçların yuva olarak telâkki edilmesi bundan dolayıdır. hâl-i hümâ-nümâsına zülfü kafeslenir kim mürg-i ma‟nâ hâne-i mısra‟da beslenir. ġeyh gâlib, . g./ saçın, kemend, ip, dâr gibi kelimelerle münasebeti asılma ve can verme hususlarına dayanır. ÂĢığın esir olarak değerlendirilmesi saçların bağlama özelliğini ön plana çıkarır. saçlar âĢıkları bağlar, kendine çeker. saç, âĢığın gönlünü yakalayan bir avcıdır: zülfün „izâra dökme beni sayd-ı bend içün kılmam girifte gönlümü öyle kemende bende enderunlu vâsıf, . g./ zülf-i dirâzın etmiĢ peyvend-i gerden-i cân ol tıfl-ı nev-resîde yâ rab mu‟ammer olsun nâilî, . g./ arzû-yı dâne-i hâl-i ruhunla „âkıbet düĢdi hayfa mürg-i dil sayyâd-ı zülfün dâmına bâkî, . g./ karanlık ve hapsetme özelliği dolayısıyla saçlar ve çene çukuru bir zindandır. ÂĢıkların gönlü, sevgilinin zindana benzeyen saçlarında kalır ve dert çeker. fuzûlî, aĢk ıstırabından kurtuldum fakat saçını ve çene çukurunu görünce tekrar eski çaresizliğim ve gamım peyda oldu diyor: kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer bend ü zindân-ı gam ü mihnetten olmuĢtum halâs Âh kim düĢtüm yine zülf ü zenahdânın görüp fuzûlî, . g./ saçlar âĢıkların gönlünü avlamasından hareketle Ģahbâz, Ģahin ve hümâ gibi bazı kuĢ çeĢitleri ile anılmıĢtır. rüzgâr tarafından uçurulması, dağılması nedeniyle benzetilir. ġeyhî, güzelin saçları için ya yanağın tavusu ya da âlemi avlayan bir Ģahbazdır diyor: tâvûs-ı rûh mu çemen içinde perçemin yâ kuds-i Ģâhbâz ki âlem-Ģikârdır ġeyhî. . g./ avcılığı ve uçucu olması dolayısıyla saçları nâilî Ģahine benzetiyor: bâl ü per açdı üstüne Ģâhin-i zülf-i yâr bi‟llah hamâm-ı dil nice remkerde olmasın nâilî, . g./ talih kuĢu olması nedeniyle saçlar hümaya benzetilir. saçların gölgesi yanağa ve yüze düĢmüĢ olarak Ģiirlerde sıkça kullanılır. saçlar yanak üzerine düĢüp ayva tüylerine mutluluk verir, ayva tüyleri yanak üzerinde bulunmalarından dolayı çok talihlidir. (deniz , ) ahmed paĢa‟nın hat mı bu yâ gönlümün tafsîl-i vasf-ı hâlidir yâ hümâ-yı zülf-i yârun sâye-i ikbâlidür ahmed paĢa, .g./ dediği beytinde âĢıkların sevgilinin yanağına hiçbir zaman ulaĢamamasını ve ona kavuĢmanın büyük bir talih olduğu; ayva tüylerinin yanak üzerinde olması ve bundan dolayı talihli olarak değerlendirildiği görülür. sevgilinin saçlarının yılan olarak tasavvuru daha çok Ģekil benzerliğine dayanır. Öldürme ve yakalama özellikleri ile âĢığın içinde bulunduğu duruma gönderme yapmak için kullanılmıĢtır. renk bakımından da bazı yılan cinsleriyle de ilgi kurulabilir. hazinelerin harabelerde saklanması ve yılanların da buraları mesken tutması sebebiyle, saçlar sevgilinin hazinesini bekleyen yılanlara benzetilir. ayrıca yılanların kuĢ yuvalarına düĢkün olması ve saçların âĢıkların kuĢa benzetilen gönüllerinin yuvası olmasından hareketle benzetmelere konu olur (sefercioğlu , ). saçın ef‟isi inen kılmamağa hakı helâk hak lebin hokkasını dopdolu tiryâk eyler ġeyhî, . g./ saçlar sevgilinin hazinesini bekleyen ejderhalara benzetilir. efsaneye göre hazineleri yılanlar korur ve hazineye ulaĢmak isteyenleri öldürürmüĢ. sevgilinin yüzü ve yanağı bir hazinedir. saçlar bu hazineyi bekleyen yılan veya ejderha olarak tasavvur edilir. bu hazineye ulaĢmak isteyen âĢığın ölümü göze alması gerekir. ġeyh gâlib bu durumu aĢağıdaki beytinde Ģu sözleriyle dile getiriyor: bâ‟is-i bünyâd-ı hüsnün kalb-i virândır senin zülfün ejder gösteren bu genc-i pinhândır senin ġeyh gâlib . g./ sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer yılan zehirli bir hayvandır ve bu yüzden onu yakalamak isteyen kiĢi kendini efsunlatır. zehirli hayvanlara karĢı efsunlanmak onları etkisiz hale getirir (deniz , ). fuzûlî sevgilinin dudağı gibi kimsenin sihir yapamayacağını söylüyor. yılana benzeyen saçları yanaklar üzerinde tutan onu yakalayan dudakların yaptığı efsundur: zikr-i lebinde zülfüne cân oldu destres anun kimi kim okuyup efsun yılan tutar fuzûlî, . g./ saçın akreple anılmasında kıvrımlı uçlarının ve renginin önemi vardır. akrepler çoğunlukla geceleri görülür. gece ayın doğması ve sevgilinin yüzünün ay olarak tasavvur edilmesinden, yanaktaki saçlar akrep olarak değerlendirilir. sevgilinin akrebe benzeyen saçları ay yüzüne döküldüğü zaman âĢık periĢan olur beladan kurtulamaz. astrolojide ayın burçlarla olan ilgisi malumdur. Özellikle akrep burcuyla ay bir araya geldiği zaman kargaĢa, savaĢ ve fitnenin arttığına inanılır (deniz , ). ġeyhî, sevgilinin yanağına düĢmüĢ olan saçları akrebe benzeterek ayın hangi burçta olduğunu anladığını vurguluyor: göreli zülfünü haddinde bildim ki akreb mâh-ı tâbân menzilidir ġeyhî, . g./ . dil-ârâ, dil-âvîz, dil-dâr, dil-rübâ, dest-i niyâz, dest-i tedâvül, mahz-ı cân, sevdâ güzelliğinden ve âĢıklar üzerindeki etkisinden dolayı saçların gönül alan, gönlü süsleyen, gönlü kapan, gönle asılan, gönül çeken, devlet eli, dua ve can gibi kelimelerle anıldığını görüyoruz. farz eyle ki girdâb-ı yem-i hayrete düĢdük dâmen-be-kef-i zülf-i dil-ârâ mı değildir nef‟î, . k./ dil-i sad-çâk o mûy-ı müĢg-bûnun bendine kalmaz Çeker zülf-i dil-âvîzün cefâsın Ģâne incinmez bâkî, . g./ sabâ çevgân edince turra-i pertâb-ı dildârı gelip âĢıkların bir yere top oldu dil-i zârı nef‟î, . k./ dil-rübâdır zülfü amma dil-niĢîndir gamzesi nâz ederse yaraĢır pek nâzenîndir gamzesi nef‟î, . g./ sevgilinin fesinin altından yüzüne doğru düĢmüĢ olan saçlar niyaz eli olarak değerlendirilmiĢtir. saç âĢıkların gönüllerini avlar. saç, bazen bir zulüm eli bazen de devlet eli olarak ele alınmıĢtır. kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer zîr-i fesden yâ meğer dest-i niyâzıdır anun ġimdi düĢmüĢ perçemi sayd-ı derûn sevdâsına ġeyh gâlib, . k./ yanak üzerine düĢmüĢ saçlar, yanak için bir devlet eli, iyilik ve ihsan olarak değerlendirilir. sevgilinin saçlarına ulaĢmak büyük bir talihtir. yûsuf-ı hüsne zelihâ-yı hevesden gûyâ dâmen-i ârıza bir dest-i tedâvüldür zülf ġeyh gâlib, . g./ ġeyhî saç için canın kendisi olduğunu baĢka bir Ģeye teĢbih etmenin hata olacağını Çin, hıta, hoten kelimelerinin Ģekil ve koku özelliklerini de çağrıĢtıracak Ģekilde dile getiriyor: mahz-ı cândır saçı çîni bilirim etme hata deme teĢbîh edüben müĢk-i hotendir kokusu ġeyhî, . g./ saçın âĢık üzerindeki etkisini en iyi dile getiren benzetme onun sevda olarak telakki edilmesidir. sevda kalpte bulunan siyah bir sıvının aslıdır ve daha çok süveyda diye anılır. kara sevda tabiri de siyah olmasından dolayıdır. kelime hem renk hem de aĢka düĢmek anlamlarıyla Ģiirlerde kullanılmıĢtır (pala , ). mihr salmazsan bana rahm eylemezsen bunca kim sâye tek sevdâ-yi zülfün pây-mâl eyler beni fuzûlî, g./ saçlar o kadar güzeldir ki sadece âĢıklar değil sevgilinin kendi gözleri bile ona âĢık olur. fevzî, sevgilinin gözlerinin düĢmanca bakmasını saçı kıskanmasına ve ona âĢık olmasına bağlıyor: ger olmasaydı zülfüne dîvâne gözlerün bakmazdı dem-be-dem bana hasmâne gözlerün fevzî, . g./ sonuÇ sevgilinin saçı ile ilgili teĢbih, mecaz ve tasavvurlar bu kadarla sınırlı değildir. biz elimizde bulunan sınırlı sayıdaki divandan hareketle bir durum değerlendirmesi yaptık. bu engin vadideki çalıĢmalar arttıkça daha ayrıntılı sonuçlar elde edilecektir. makalemizin bu konuya sadece bir temas etme özelliğinde olduğu göz önünde bulundurulmalıdır. saça ait teĢbih ve mecazların Ģairlerin elinde iĢlene iĢlene geliĢtirildiği ve zenginleĢtirildiği görülmektedir. yüzyıllar ilerledikçe teĢbih ve mecazların Ģairlerin hayal dünyasında yoğrularak, değiĢik kelime ve tamlamalarla ifade edilmeye baĢlandığı fark edilmektedir. Ġlk dönem Ģairleri saçı anlatmak için zülf, perçem, sümbül, müĢg ve amber gibi benzetme unsurlarını ağırlıklı olarak kullanmıĢlardır. zülf, perçem, gîsû, turra, külâle, mû(y) gibi kelimeler zamanla iĢlene iĢlene umumi olarak saç kelimesinin anlamını ihtiva etmeye baĢlamıĢtır. bir Ģaire özgü teĢbih, mecaz ve tasavvurlar da vardır. bu benzetme ve ifade unsurları geleneğin çizdiği çerçeveyi zorlamayan türdendir. genel sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer hatlarıyla saç hangi benzetmelere konu olduysa bu benzetmelerle paralel anlatımlar vardır. benzetme unsurları değil de yoğunlaĢma noktaları daha fazla değiĢkenlik arz eder. saçı anlatmak için aralarında küçük farklar da olsa aynı anlamı ihtiva eden kelimelerin arapça, farsça ve türkçeleri kullanılmıĢtır. Örneğin yılan kelimesinin yanı sıra farsça mâr, ejder; arapça su‟ban, ef‟î kelimeleri de kullanılmıĢtır. bu durum dilin ve edebiyatın tarihî geliĢimiyle alakalıdır. ġeyhî gibi ilk dönem Ģairlerimizde türkçe unsurlar, daha sonraki Ģairlerimizde ise arapça ve farsça unsurlar fazladır. sevgilinin vasıflarının en önde gelenlerinden biri olan saç, büyük ölçüde güzelliği sağlayan bir unsur olarak yer almıĢtır. onun bu önemi, yüzün güzelliğini daha da artırmasından kaynaklanmaktadır. yine kaĢ, kirpik, hat, yanak ve dudak bu güzelliği tamamlayıcı unsurlardandır. tek baĢına yüz, güzellik için yeterli değildir. bütün bu unsurların terkibi onu güzel kılmaktadır. saç denildiği vakit zülf akla gelmektedir. ġairler zülf kelimesini Ģiirlerinde çok fazla kullanmıĢtır. saça ait benzetme, tasavvur ve mecazların ağırlığını Ģekle ait hususiyetler oluĢturmaktadır. saç ile ilgili sümbül, müĢg, periĢan, siyah, amber, ham ve fitne benzetmeleri Ģairlerin çok fazla üzerinde durduklarıdır. saça ait benzetmelerin çokluğu âĢığı etkileyen en önemli güzellik unsuru olmasından kaynaklanır. saçlar âĢıklar üzerindeki etkisinden dolayı periĢan, bela, fitne çıkaran, hileci, büyücü, tuzak, gönül avlayan, kargaĢa yaratan gibi unsurlarla sıklıkla anılır. bu tür benzetmelerde renk ve Ģekil hususiyetleri de göz önünde bulundurulmuĢtur. saçların dağınıklığı ile âĢıkların gönüllerinin periĢanlığı arasında hep bir ilgi kurulmuĢtur. saç Ģekli, kokusu ve rengiyle âĢığı daima kendine bağlamıĢtır. saçlar aĢığı cezbeden aynı zamanda da eziyet eden özellikleriyle karĢımıza çıkar. ÂĢıklar için saçlar yakalanmaktan, bağlanmaktan kaçılamayacak bir güzelliğe sahiptir. ÂĢıklar hem saça bağlanmaktan Ģikâyet ederler hem de ona bağlı kalmayı arzularlar. kaynakÇa ahmet vefik paĢa, lehçe-i osmanî, haz. recep toparlı, tdk. yay. ankara, . akkuġ, metin, nef’î dîvânı, akçağ yay. ankara, . akÜn, Ömer faruk, “divan edebiyatı”, tdvİa, c. , Ġstanbul, , s. – . aksoyak, Ġ. hakkı, “manastırlı celâl‟in hüsn-i yûsuf adlı eseri” edebiyat ve dil yazıları mustafa İsen’e armağan (editörler: ayĢenur kÜlahoĞlu, süer eker), ankara, , s. – . akyÜz, kenan vd. fuzûlî divanı, akçağ yay. ankara, . ari, ahmet ( ), hayreti divanı’nda sevgili ve sevgilinin fiziki yapısıyla İlgili Özellikler, gazi Üniversitesi sosyal bilimler enstitüsü yayımlanmamıĢ yüksek lisans tezi, ankara. atay, hakan ( ), heves-nâme’de aşk oyunu: tâcî-zâde cafer Çelebinin Özgünlük ideali, bilkent Üniversitesi ekonomi ve sosyal bilimler enstitüsü yayımlanmamıĢ yüksek lisans tezi, ankara. ÇavuġoĞlu, mehmet, necâti bey divânı’nın tahlîli, meb. yay. Ġstanbul, . kürşat Şamil Şahİn turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer demĠr, yavuz ( ), taşlıcalı yahya bey divânı’nda sevgili ve sevgiliye ait fiziki unsurlar, gazi Üniversitesi sosyal bilimler enstitüsü yayımlanmamıĢ yüksek lisans tezi, ankara. demĠr, hiclal, “xviii. yüzyıl klâsik türk edebiyatı ġairlerinden lâzikî-zâde feyzullah nâfiz ve dîvânı Üzerine”, hacettepe Üniversitesi edebiyat fakültesi dergisi, c. , s. aralık , s. – . denĠz, sebahat, "divan ġiiri güzelinin saç ġekli", saç kitabı, kitabevi yayınları, Ġstanbul, , s. – . devellĠoĞlu, ferit, osmanlıca-türkçe ansiklopedik lûgat, aydın kitabevi, ankara, . doĞramaci, nilgün ( ), fevzî divanı, boğaziçi Üniversitesi sosyal bilimler enstitüsü yayımlanmamıĢ yüksek lisans tezi, Ġstanbul. elĠaÇik, muhittin, “bavyera devlet kütüphanesi‟nde mahbuba ait benzetme lafızlarını açıklayan bir risale”, İlmî araştırmalar, bahar , s. – . elĠaÇik, muhittin, “bavyera devlet kütüphanesi‟nde mahbubun sıfatlarına dair risale miftâhü‟t-teĢbîh‟ten bir Ġntihal mi?” türk kültürü İncelemeleri dergisi, sayı , güz , s. – . erÜnsal, Ġsmail e. “mu‟îdî‟nin miftâhu‟t-teĢbih‟i”, osmanlı araştırmaları vii-viii (ayrı basım ), Ġstanbul, . gÖkhan, asuman, “fars edebiyatında saç”, nüsha Şarkiyat araştırmaları dergisi, yıl vi, s. , bahar , s. – gÜrbÜz, mehmet, “ġiir semasının yegâne yıldızı; güzeller sultanı”, turkish studies klâsik türk edebiyatında Âşk-Âşık-maşûk, volume / summer , s. – . gÜrel, rahĢan, enderunlu vâsıf divânı, kitabevi yay. Ġstanbul, . Ġpekten, haluk, nâ’ilî dîvânı, akçağ yay. ankara, . Ġpekten, haluk, nâ’ilî hayatı sanatı eserleri, akçağ yay. ankara, . Ġpekten, haluk, fuzûlî hayatı sanatı eserleri, akçağ yay. ankara, . Ġsen, mustafa ve kurnaz, cemâl, Şeyhî divanı, akçağ yay. ankara, . kalkiġim, muhsin, Şeyh gâlîb dîvânı, akçağ yay. ankara, . kÖksal, m. fatih, “eski ġiirimizin nâdîde güzelleri”, türklük bilimi araştırmaları, s. , bahar , s. – . kurnaz, cemal, hayâlî bey divanı’nın tahlîlî, meb. yay. Ġstanbul, . kÜÇÜk, sabahattin, bâkî dîvânı (tenkitli basım), tdk. yay. ankara, . macĠt, muhsin, nedîm divânı, akçağ yay. ankara, . mütercim Âsım efendi, burhân-ı katı (haz. mürsel Öztürk, derya Örs), tdk. yay. ankara, . onan, necmettin halil, İzahlı divan Şiiri antolojisi, meb. yay. Ġstanbul, . Öztoprak, nihat, "divan ġiirinde güzelin saç rengi", saç kitabı, kitabevi yayınları, Ġstanbul, , s. – . pala, Ġskender, ansiklopedik divan Şiiri sözlüğü, Ötüken yay. Ġstanbul, . sevgilinin güzellik unsurlarından saç ve saçın… turkish studies international periodical for the languages, literature and history of turkish or turkic volume / summer sefercĠoĞlu, m. nejat, nev’î divanı’nın tahlîli, akçağ yay. ankara, . ġerafettin râmî, enisü’l-uşşak ( Çev. turgut karabey, numan külekçi, habib Ġdris ), ankara, . ġemseddin sâmî, kâmûs-ı türkî, Çağrı yay. Ġstanbul, ġafak, yakup, “sürûrî‟nin bahrü‟l maârif‟i ve bu eserdeki teĢbih ve mecaz unsurları”, türkiyat araştırmaları dergisi, s. , konya, , s. – . ġahĠn, kürĢat ġamil ( ), sevgilinin güzellik unsurlarından saç, kaş, kirpik, hat, kırıkkale Üniversitesi sosyal bilimler enstitüsü yayımlanmamıĢ yüksek lisans tezi, kırıkkale. tanyildiz, ahmet, “sevgilide güzellik unsuru olarak saç”, turkish studies/türkoloji araĢtırmaları, volume / winter , s. – . tarlan, ali nihat, fuzûlî divanı Şerhi, akçağ yay. ankara . tolasa, harun, ahmet paşa'nın Şiir dünyası, akçağ yay. ankara, a t l -p h y s- sl id e - - ju ly the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia the charmonium and beauty physics programme in atlas maria smizanska lancaster university, uk the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia layout of the talk • atlas j/ψ selection strategy for early beam conditions • mass determination, method, results • kinematic properties of j/ψ with early selections • first performance results with j/ψ • b-physics program – two examples of early measurements under preparation – two examples future high sensitivity b-measurements the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia early j/ψ: event selections • p-p collision data at tev, taken between march th and may th • integrated luminosity of data used for this study: . ± . nb- • strategy: collect largest possible statistics; determine mass, resolution and j/ψ properties, understand backgrounds • trigger requirements: • minimum bias trigger scintillators (mbts) mounted at each end of the detector in front of the liquid argon endcap-calorimeter cryostats at z= ± . m. the mbts trigger - requires at least two hits from either sides of the detector. • l minimum bias trigger was not prescaled for runs with luminosity < cm− s− . • a dedicated muon software trigger commissioning chain at the event filter level initiated by the mbts l trigger searches for muon track in the entire muon spectrometer • analysing data in mbts stream we requested at least one muon must pass the ef muon-commissioning chain with a muon of any pt reconstructed in the muon system • to ensure collision events are selected, at least tracks form a primary vertex. the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia µµ and j/ψ selections types of muons used: • combined muon: • statistical combination of track parameters and the covariance matrices of muon system(ms) track and inner detector (id) track; • the tracks with tight matching criteria selected to create a combined muon track traversing the id and ms • tagged muon: • muon segments matched to id tracks extrapolated to ms. reconstructed muon adopts parameters of id track. • pairs of muons with at least one combined muon were retained cosmic ray background: • may come from a pair formed by a cosmic muon and a muon from the collision. the probability is very small ( < − ) from the gev data analysis • a cosmic muon mimicking a j/ψ decaying back-to-back is excluded - muons detected in the ms can only have momentum higher than gev. the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia µµ and j/ψ selections, cont • id selections, vertexing: • >= hit in the pixels and hits in silicon strip layers • pt > . gev on each track • tracks fitted to a common vertex using vertexing tools based on kalman filter. • no constraints on mass or pointing to the primary vertex, and a very high vertex fit χ upper limit is applied (χ < ). • only id track parameters of muons used for this j/psi study • same sign pairs retained for cross-checking. • cuts not optimized to reject backgrounds, since the aim of this study is to understand the shape of the low pt combinatorial background the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia early j/ψ signal in atlas • j/ψ mass and number of signal events from unbinned maximum-likelihood fit an unbinned maximum-likelihood fit is used to extract the j/!mass and the number of j/! signal candidates from the data. the likelihood function is defined by: l= n ! i= " fsignal(m i µµ)+ fbkg(m i µµ) # ( ) wheren is the total numberofpairsofoppositely chargedmuons in the invariantmass range | η| > . , barrel |η| < . • no statistically significant mass shifts from the pdg value observed in any of the pseudorapidity regions both muons barrel bb both muons in endcap ee one muon barrel one endcap (eb) table : summary of fit results tomass distributions of j/! ! µ+µ" candidates. the number of back- groundevents is given in the rangemj/!± "m. the samefit is applied toprompt j/!mcdata, assuming fbkg # in the formula . results for data before vertexing are shown for comparison. mj/!, gev "m,mev nsig nbck s all data . ± . ± ± ± . ± . mc . ± . ± . . ± . data n/v . ± . ± ± ± . ± . bb data . ± . ± ± ± . ± . mc . ± . ± . . ± . data n/v . ± . ± ± ± . ± . eb data . ± . ± ± ± . ± . mc . ± . ± . . ± . data n/v . ± . ± ± ± . ± . ee data . ± . ± ± ± . ± . mc . ± . ± . . ± . data n/v . ± . ± ± ± . ± . table : the fraction ofmuon pairs in the reconstructed j/! in data andmc combined combined combined tagged data ( . ± . )% ( . ± . )% mc ( ± . )% ( ± . )% the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia comparison with like sign pairs early di-muon pairs selected at lowest pt have specific features visible when comparing like sign pairs with j/ψ candidates • like sign pairs almost match the level of the j/ψ background (unlike pairs) in the side bands • source of both dominated by muons from k/pi decays • very little b/c content in tails di-muon pairs of opposite sign in the j/ψ region have evidently different kinematic properties from the like sign pairs di-muon pairs of opposite sign in the j/ψ region have evidently different kinematic properties from the like sign pairs the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia atlas b-physics program • atlas b-physics program is realised in following sub-projects hf quarkonia measurements b → j/ψ (inclusive, exclusive) channels rare b-decays bsd →μμ, b →s μμ, b →d μμ production properties of b and d-mesons decaying into hadrons • each sub-project has tasks/measurements for early, medium and advanced periods • first measurements, in addition to physics results, serve to improveunderstanding of detector performance to allow later high precision measurements • selected examples of mc based studies are given further for the early and for advanced periods • complete b-physics program arxiv: . ; cern-open- - , chapter . the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia early measurements with exclusive b → j/ψ mass (mev) mass (mev) decay time (ps) - x j/bb x j/pp * k j/ db parameter simulated value fit result with statitical error !, ps! . . ± . m(b), gev . . ± . !, ps . ± . mass (mev) mass (mev) decay time (ps) - x j/bb x j/pp * k j/ db !s, ps! . . ± . m(b), gev . . ± . !, ps . ± . mass (mev) mass (mev) decay time (ps) - x j/bb x j/pp * k j/ db mass (mev) mass (mev) decay time (ps) - x j/bb x j/pp j/ sb applying simultaneous mass - lifetime likelihood fit to events • b → j/ψ k * ( pb- ) • bs → j/ψ φ ( pb- ) lifetimes measured with sensitivity better than %. early lifetime measurements test the calibrations and alignments necessary for precise cpv studies applying simultaneous mass - lifetime likelihood fit to events • b → j/ψ k * ( pb- ) • bs → j/ψ φ ( pb- ) lifetimes measured with sensitivity better than %. early lifetime measurements test the calibrations and alignments necessary for precise cpv studies applying simultaneous mass - lifetime likelihood fit to events • b → j/ψ k * ( pb- ) • bs → j/ψ φ ( pb- ) lifetimes measured with sensitivity better than %. early lifetime measurements test the calibrations and alignments necessary for precise cpv studies the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia differential cross section b+ →j/ψ k + the b+ → j/ψk+ total and differential production cross- sections • with pb− the total cross- section can be measured with a statistical precision better than % • the differential cross-section with precision of the order of %. pt range [gev] pt ! [ , ] pt ! [ , ] pt ! [ , ] pt ! [ , ] a [%] . ± . . ± . . ± . . ± . !(b+) [ mev] . ± . . ± . . ± . . ± . table : efficiency a and b+ masswidth !(b+) for the various pt bins. b+ mass (mev) e ve nt s / ( . m ev ) nbkg = +/- nsig = +/- sigma = . +/- . mev b+ mass (mev) e ve nt s / ( . m ev ) (a) ! pt < gev b+ mass (mev) e ve nt s / ( . m ev ) nbkg = +/- nsig = +/- sigma = . +/- . mev b+ mass (mev) e ve nt s / ( . m ev ) (b) ! pt < gev b+ mass (mev) e ve nt s / ( . m ev ) nbkg = +/- nsig = +/- sigma = . +/- . mev b+ mass (mev) e ve nt s / ( . m ev ) (c) ! pt < gev b+ mass (mev) e ve nt s / ( . m ev ) nbkg = . +/- . nsig = +/- sigma = . +/- . mev b+ mass (mev) e ve nt s / ( . m ev ) (d) ! pt < gev figure : fit of the b+ mass in various pt ranges: pt ! [ , ] gev (a), pt ! [ , ] gev (b), pt ! [ , ] gev(c), pt ! [ , ] gev (d). total cross-section a [%] . ± . !(b+) [ mev] . ± . table : overall efficiency and b+ masswidth for all b+ with pt > gev. . lifetime measurement themeasurement of the lifetime " of the selected b+ candidates is a sensitive tool to confirm the beauty contents in a sample, in particular the number of the reconstructed b+ " j/#k+ decays obtained in the bb̄ " j/#x dataset. theproper decay time is defined as t = $/c. for this analysis, no cut on the proper decay length $ (equation ) of the j/# candidate or the b+ candidate should be applied. theproperdecay timedistribution in the signal regionb+ " j/#k+ canbeparametrised asaconvo- lution of an exponential functionwith agaussian resolution function, while the background distribution b-physics – production cross-section measurements and study of the . . . fit of the b+ mass in four pt! ranges signal lifetime ! [ps] . ± . bg lifetime ! [ps] . ± . bg lifetime ! [ps] . ± . table : results for the lifetime fit. statistical and systematic uncertainties from the analysis presented above, the expected number of reconstructed b+ candidates amounts to perpb! . this implies that sufficient statistics canbecollected for a reliable cross-sectionmeasurement, after just a fewmonthsofdata takingat the initial low luminosityphaseof thelhc.this scenario isvalid for a luminosity less than l = cm! s! , since the analysis was performed without pileup events and contains no special trigger requirements or prescaling other than a singlemuonwith pµt > gevat level- . for the measurements presented in this note the main sources of systematic uncertainties are the same. the uncertainty from the luminosity in the initial phase is estimated to be % and will be reduced to about . % after . fb! of data. the uncertainty from the pdf’s is estimated to be %, while the scale uncertainty of the nlo calculations is about %. finally, the uncertainty originating from the muon identification is about %. assuming gaussian distributions for the above mentioned uncertainties, the total systematic uncertainty of the signal varies from . % to %and is dominated by the uncertainty in the luminosity. given that a statistical precision of o( %) will be reachedwith an integrated luminosity of . fb! , the contribution of the systematics will dominate the uncertainties of the first measurements. this is the case even for the differential cross-section measurement. although the statistics in each pt bin is limited, the total uncertainty is dominated by the systematic uncertainties in the branching ratio of the b+ ! j/"k+ and in the luminosity, which are of the same order. for the exclusive cross-section measurement in the b+!j/"k+ channel, the relative uncertainties of the differential and total cross- sections are given in table . therein, the first row of the table contains the quadratic sum of the statistical uncertainty corresponding to an integrated luminosity of . fb! and the uncertainty in the efficiency. the latter is based on the statistics of the monte carlo dataset used. the second row is calculated by adding in quadrature the above uncertainty to the systematic uncertainty of the luminosity and the branching ratio for every pt bin. for the high statistics pt bins as well as for the total cross-section, the total relative uncertainty is dominated by systematic errors, originating mainly from the uncertainty in the luminosity, which is assumed tobe %for the initial phase, and the %uncertainty in thebranching ratioofb+ ! j/"k+. the effect of the assumed background shape on the measurements is estimated to be less than %. finally, the precision of the lifetimemeasurement, for the same integrated luminosity is . %,where no systematic effects are taken into account. pt range [gev] pt " [ , ] pt " [ , ] pt " [ , ] pt " [ , ] pt " [ ,inf) stat. + a [%] . . . . . total [%] . . . . . table : statistical and total uncertainties for the b+ ! j/"k+ differential and total cross-sectionmea- surements for an integrated luminosity of . fb! . total uncertainties include luminosity and br systematic uncertainties. b-physics – production cross-section measurements and study of the . . . the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia production polarization of Λb with fb- polarization varies with pseudorapidity thus atlas/cms and lhcb can perform complemetary measurements to map full range. with fb- the Λb polarization in atlas can be measured with precision of . • the atlas performance was analysed for first j/ψ→μμ shown that di-muon performance with real data consistent with mc predictions • the mc simulation of bs →μμ potential (left) to test potential with fb- was done with trigger menus for > • both muons required pt> gev. • low pt b-physics di-muon triggers will be applied at low instantaneous luminosities of early lhc period to maximize reach for first sensitivity • at ~ dedicated triggers prepared to use full atlas potential for bs →μμ • bs →μμ bd →μμ in physics program for atlas upgrade bs →μμ signal and backgrounds after applying all selection cuts - relevant at > cm - s - • the atlas performance was analysed for first j/ψ→μμ shown that di-muon performance with real data consistent with mc predictions • the mc simulation of bs →μμ potential (left) to test potential with fb- was done with trigger menus for > • both muons required pt> gev. • low pt b-physics di-muon triggers will be applied at low instantaneous luminosities of early lhc period to maximize reach for first sensitivity • at ~ dedicated triggers prepared to use full atlas potential for bs →μμ • bs →μμ bd →μμ in physics program for atlas upgrade • the atlas performance was analysed for first j/ψ→μμ shown that di-muon performance with real data consistent with mc predictions • the mc simulation of bs →μμ potential (left) to test potential with fb- was done with trigger menus for > • both muons required pt> gev. • low pt b-physics di-muon triggers will be applied at low instantaneous luminosities of early lhc period to maximize reach for first sensitivity • at ~ dedicated triggers prepared to use full atlas potential for bs →μμ • bs →μμ bd →μμ in physics program for atlas upgrade the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia atlas potential for b → µµ selection cut b s ! µ+µ! efficiency bb̄ ! µ+µ!x efficiency iµµ > . . ( . ± . ) · ! lxy > . mm . ( . ± . ) · ! ( . ± . ) · ! " < . rad . ( . ± . ) · ! mass in ["#, #] . . total . . · ! ( . ± . ) · ! events yield . + ! the charmonium and beauty physics programme in atlas, m.smizanska, beach , perugia summary • early j/ψ data taken with minimum bias trigger show excellent agreement with expected performance • reproducing j/ψ pdg mass in all pseudorapidity regions - confirms that pt scale understood at low pt range • j/ψ mass resolution over entire pseudorapidity regions of detector - consistent with mc. • b-physics program prepared for both early and advanced periods. • atlas will significantly contribute to b →μμ potential as an instantaneous lhc luminosity will be increased to several times and to a nominal value rare b decays for detector upgrade being prepared. l h c b -p r o c - - / / nuclear physics b proceedings supplement ( ) – nuclear physics b proceedings supplement cp violation in charm and beauty decays at lhcb m. pepe altarelli cern, geneva, switzerland abstract lhcb is a dedicated heavy flavour physics precision experiment at the lhc searching for new physics (np) beyond the standard model (sm) through the study of very rare decays of beauty and charm-flavoured hadrons and precision measurements of cp-violating observables. in this review i will present a selection of recent precision measurements of cp-violating observables in the decays of beauty and charm-flavoured hadrons. these measurements are based on an integrated luminosity of up to . fb− collected by lhcb in . keywords: lhcb, flavour physics, cp violation fourth workshop on theory, phenomenology and experiments in flavour physics - june , anacapri, italy . introduction the lhcb detector has been taking data with high efficiency during the last three years of operation at the lhc, producing a wealth of exciting physics re- sults, which have made an impact on the flavour physics landscape and proved the concept of a dedicated heavy flavour spectrometer in the forward region at a hadron collider. the lhc is the world’s most intense source of b hadrons. the bb cross-section in proton-proton colli- sions at √ s = tev is measured to be ∼ µb, imply- ing that more than bb pairs were produced in lhcb in , when an integrated luminosity of . fb− was collected. the cc cross-section is about times larger email address: monica.pepe.altarelli@cern.ch (m. pepe altarelli) on behalf of the lhcb collaboration c© cern on behalf of the lhcb collaboration, license cc-by- . . than the bb cross-section, giving lhcb great potential in charm physics studies. as in the case of the tevatron, a complete spectrum of b hadrons is available, including bs, bc mesons and b baryons, such as Λb. at the nominal lhc design luminosity of cm− s− , multiple pp collisions within the same bunch crossing (so-called pile-up) would signif- icantly complicate the b decay-vertex reconstruction and flavour tagging, and increase the combinatorial background. for this reason the detector was designed to operate at a reduced luminosity. the luminosity at lhcb is locally controlled by transverse displace- ment of the beams (so-called “levelling”) to yield l = × cm− s− (approximately a factor of two above the original lhcb design value) at which the average event pile-up per visible crossing is ∼ . running at relatively low luminosity has the additional advantage of reducing detector occupancy in the tracking systems and limiting radiation damage effects. the dominant bb-production mechanism at the lhc http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / m.pepe altarelli / nuclear physics b proceedings supplement ( ) – is through gluon-gluon fusion in which the momenta of the incoming partons are strongly asymmetric in the pp centre-of-mass frame. as a consequence, the bb pair is boosted along the direction of the higher momentum gluon, and both b hadrons are produced in the same for- ward (or backward) direction in the pp centre-of-mass frame. the detector is therefore designed as a single- arm forward spectrometer covering the pseudorapidity range < η < , which ensures a high geometric ef- ficiency for detecting all the decay particles from one b hadron together with decay products from the accompa- nying b hadron to be used as a flavour tag. the key de- tector features are a versatile trigger scheme efficient for both leptonic and hadronic final states, which is able to cope with a variety of modes with small branching frac- tions; excellent vertex and proper time resolution; pre- cise particle identification, specifically for hadron (π/k) separation; precise invariant mass reconstruction to re- ject background efficiently. a full description of the de- tector characteristics can be found in ref.[ ]. in this review, i report on a few recent precision measurements of cp-violating observables in decays of beauty and charm-flavoured hadrons, while the study of rare decays at lhcb is covered by a separate contribu- tion [ ]. . measurement of the bs mixing phase the cp-violating phase φs between b s -b s mixing and the b → ccs decay amplitude of the bs meson is determined with a flavour tagged, angular analysis of the decay b s → j/ψφ, with j/ψ → µ +µ− and φ → k+ k−. this phase originates from the interfer- ence between the amplitudes for a bs (bs) to decay di- rectly into the final state j/ψφ or to first mix into bs (bs) and then decay. in the sm, φs is predicted to be ' − βs, where βs = arg(−vtsv∗tb/vcsv∗cb) = ( . ± . ) − rad [ ]. however, np could significantly modify this prediction if new particles contribute to the b s -b s box diagram. the cdf and d collaborations [ , ] have reported measurements of the bs mixing phase based on approx- imately , b s → j/ψφ candidates from an inte- grated luminosity of . fb− (i.e. the full cdf run ii dataset) and , b s → j/ψφ candidates from fb − , respectively. both results are compatible with the sm expectation at approximately one standard deviation in the (φs, ∆Γs) plane. lhcb has presented results based on a sample that contains approximately , b s → j/ψφ candidates from an integrated luminosity of . fb− [ ]. besides having a very large and clean signal yield, lhcb also benefits from an excellent proper time resolution to resolve fast bs oscillations, which is measured to be ∼ fs, compared to a bs oscillation period of ∼ fs. the other key experimental ingredient is flavour tag- ging, which is performed by reconstructing the charge of the b-hadron accompanying the b meson under study. the analysis uses an opposite-side flavour tagger based on four different signatures, namely high pt muons, electrons and kaons, and the net charge of an inclusively reconstructed secondary vertex, with a combined effec- tive tagging power of ∼ . %. the decay b s → j/ψφ is a pseudoscalar to vector-vector transition. total an- gular momentum conservation implies l = , , and therefore the j/ψφ final state is a mixture of cp-even (l = , ) and cp-odd (l = ) eigenstates, which can be disentangled on a statistical basis. this is accom- plished by performing an unbinned maximum likeli- hood fit to the candidate invariant mass, decay time, initial bs flavour and the decay angles in the so-called transversity frame [ ]. the fit yields the following re- sult for the three main observables, namely φs, the de- cay width, Γs, and the decay width difference between the light and heavy bs mass eigenstates, ∆Γs φs = − . ± . (stat) ± . (syst) rad, Γs = . ± . (stat) ± . (syst) ps − , ∆Γs = . ± . (stat) ± . (syst) ps − . this is the world’s most precise measurement of φs and the first direct observation for a non-zero value for ∆Γs. these results are fully consistent with the sm, indicat- ing that cp violation in the bs system is small. actu- ally, there exists a second mirror solution in the plane ∆Γs vs φs, which arises from the fact that the time- dependent differential decay rates are invariant under the transformation (φs, ∆Γs) → (π − φs,−∆Γs) (plus an appropriate transformation of the strong phases). lhcb has recently resolved this ambiguity [ ] by studying the dependence of the strong phase difference between the s -wave and p-wave amplitudes on the k+ k− mass from b s → j/ψk + k− decays in the region around the φ( ) resonance. the solution with positive ∆Γs is favoured with a significance of . standard deviations, indicating that in the bs system the lighter cp mass eigenstate that is almost cp even decays faster than the state that is almost cp odd. the mixing-induced phase φs is also measured in the decay bs → j/ψπ+π− [ ]. the branching fraction for this decay is ∼ % of bs → j/ψφ, with φ → k+ k−. however, this final state has been shown to be almost cp pure with a cp-odd fraction larger than . at m.pepe altarelli / nuclear physics b proceedings supplement ( ) – . cdf lhcb atlas combined sm . . . . - . - . - . . . . . % cl contours ( ) hfag fall lhcb . fb — + cdf . fb — + atlas . fb + d fb — — d figure : % confidence-level contours in the (φs, ∆Γs) plane for the individual experimental measurements, their combined contour (solid line and shaded area), as well as the sm predic- tions (black rectangle). % cl, and there is no need for an angular analysis. about , signal events are selected in . fb− of data, yielding the result φs = − . + . + . − . − . rad. the two datasets are combined in a simultaneous fit, lead- ing to the preliminary result φs = − . ± . ± . rad [ ], in excellent agreement with the sm. the precision for this result is completely dominated by the statistical uncertainty and therefore significant improve- ments are expected with more data. figure shows % confidence-level contours in the (φs, ∆Γs) plane for the individual experimental measure- ments, their combined contour, as well as the sm pre- dictions [ ]. the combined result is consistent with these predictions at the . σ level. . measurement of the weak phase γ from tree-level decays the angle γ is currently the least precisely known pa- rameter of the ckm unitarity triangle. the direct de- termination of γ via fits to the experimental data gives ( ± )◦ [ ] or ( ± )◦ [ ], depending on whether a frequentist or bayesian treatment is used. in terms of the elements of the ckm matrix, this weak phase is defined as γ = arg(−vudv∗ub/vcdv∗cb). it is of par- ticular interest as it can produce direct cp violation in tree-level decays involving the interference between b → cus and b → ucs transitions that are expected to be insensitive to np contributions, thus providing a benchmark against which measurements sensitive to np through loop processes can be compared. one of the most powerful ways to measure the angle γ is through charged b decays to open charm, b± → dh±, where d stands for a d or a d and h indicates either a pion or kaon. decays in which the hadron h is a kaon carry greater sensitivity to γ. the method is based on two key observations: . these decays can produce neutral d mesons of both flavours via colour- favoured or colour-suppressed decays . neutral d and d mesons can decay to a common final state, for ex- ample through cabibbo-favoured or doubly cabibbo- suppressed feynman diagrams (ads method [ ]) or through decays to cp eigenstates such as k+ k− or π+π− (glw method [ ]). in the ads case, the reversed sup- pression between b and d decays results in very sim- ilar amplitudes leading to a high sensitivity to γ. the relative phase between the two interfering amplitudes for b+ → dk+ and b+ → dk+ is the sum of the strong and weak interaction phases, while in the case of b− → dk− and b− → dk− it is the difference be- tween the strong phase and γ. therefore both phases can be extracted by measuring the two charge conjugate modes. in addition, there is a dependence on the ratio between the magnitude of the suppressed amplitude and the favoured amplitude rb. lhcb has performed an analysis of the two-body b± → dh± modes in which the considered d meson fi- nal states are π+π−, k+ k−, the cabibbo-favoured k±π∓ and the cabibbo-suppressed π±k∓ [ ]. for both glw and ads methods the observables of interest are cp asymmetries and partial widths. exploiting . fb− of data, the first observation of the suppressed ads mode b± → [π±k∓]d k± was performed. this is illustrated in the top plots of fig . a large asymmetry is visible in the b± → [π±k∓]d k± mode (by comparing the signal yield for b+ and b−) while for the b± → [π±k∓]dπ± ads mode there is the hint of an (opposite) asymme- try. by combining all the various modes cp violation in b± → dk± was observed with a . σ significance. ) c e v e n ts / ( m e v / ) c e v e n ts / ( m e v / - k d ] + k-π[→ - b lhcb + k d ] - k + π[→ + b lhcb -π d ] + k-π[→ - b lhcb ) c) (mev/ ± dh(m ) c) (mev/ ± dh(m + π d ] - k + π[→ + b lhcb figure : invariant mass spectra for b± → [π±k∓]dh± events; the left plots are b− candidates, b+ are on the right. the dark (red) curve in the top plots represents the b → dk± events, the light (green) curve in the bottom plots is b → dπ±. m.pepe altarelli / nuclear physics b proceedings supplement ( ) – the three-body final state d → k s h +h−, with h = (π, k), was also studied [ ] through a dalitz plot anal- ysis. the strategy relies on comparing the distribu- tions of events in the d → k s h +h− dalitz plot for b+ → dk+ and b− → dk− decays. existing mea- surements of the cleo-c experiment [ ] were used to provide input on the d decay strong-phase parameters. based on approximately b± → dk± decays with d → k s h +h− selected from . fb− of data, the fol- lowing results were obtained for the weak phase γ and the ratio rb between the suppressed and favoured b de- cay amplitudes, γ = ( + − ) ◦, with a second solution at γ → γ + ◦, and rb = . ± . . other flavour specific final states, such as d → kπππ are exploited in a similar manner to the two- body case [ ]. however, for multi-body final states different intermediate resonances can contribute, dilut- ing cp violation effects. based on . fb− of data, the suppressed ads modes b± → [π±k∓π+π−]d k± and b± → [π±k∓π+π−]dπ± were observed for the first time with significances of . σ and > σ, respectively. a combination of the b± → dk± results from refs. [ , , ] was performed to derive an unambigu- ous best-fit value in [ , ]◦ of γ = ( . + . − . ) ◦ [ ], suggesting very good prospects for the result based on the full data-set. additional γ-sensitive measurements will also be included in the future. with the data cur- rently available on tape, lhcb should be able to reduce the error quoted above by at least a factor of two. . c p violation in charmless b decays charmless b decays represent an interesting family of channels for which a precise measurement of the charge or time-dependent cp asymmetries can play an impor- tant role in the search for np. in particular, np may show up as virtual contributions of new particles in loop diagrams. a comparison of results from decays domi- nated by tree-level diagrams with those that start at loop level can probe the validity of the sm. in particular, it was pointed out by fleischer [ ] that u-spin related decays (obtained by interchanging d and s quarks) of the type bs,d → h+h′−, with h, h′ = π, k, offer inter- esting strategies for the measurement of the angle γ: in presence of np in the penguin loops, such a determina- tion could differ appreciably from that derived from b decays governed by pure tree amplitudes discussed in sect. . lhcb has analysed very large samples of bs,d → h+h′− decays, separating the final state pions and kaons by using the particle identification provided by the rich detectors. figure shows the invariant kπ mass spectra for bs,d → kπ events based on an integrated lu- minosity of . fb− [ ]. the selection cuts are opti- mised for the best sensitivity to acp(bd → kπ) (plots a and b) and acp(bs → kπ) (plots c and d), where the cp asymmetry in the b decay rate to the final state f = kπ is defined as acp = (Γ(b→ f )−Γ(b→ f ) (Γ(b→ f )+Γ(b→ f ) . lhcb reported [ ] the most precise measurement for acp(bd → kπ) avail- able to date, with a significance exceeding σ, as well as the first evidence, at the . σ level, for cp viola- tion in the decay of the bs mesons. the effect of the cp asymmetry is visible in fig. by comparing the yields for the bd → kπ in (a) and (b) and those for the bs → kπ in (c) and (d). the cp asymmetry results need to be corrected for the effect of a possible b production asymmetry, which is studied by reconstructing a sample of bd → j/ψk∗ decays, given that cp violation in b → ccs transi- tions is expected to be small. effects related to the instrumental detection efficiencies are evaluated by us- ing data sets with opposite magnet polarities and recon- structing large samples of tagged d∗± → d (k−π+)π± and d∗± → d (k−k+)π± decays, as well as untagged d → k−π+ decays. these corrections are found to be small. lhcb has also performed measurements of time- dependent cp violation in charmless two-body b de- cays by studying the processes bd → π+π− and bs → k+ k− [ ]. the analysis is based on a luminosity of . fb− . direct and mixing-induced cp asymmetries are measured in each channel using a tagged, time- . . . . e v e n ts / ( . g e v /c ) lhcb (a) ) invariant mass (gev/c−π + k ) invariant mass (gev/c+π − k . . . . ) e v e n ts / ( . g e v /c lhcb (b) b →kπ b →kπ b →ππ b →kk b→ -body comb. bkg s s ) e v e n ts / ( . g e v /c . . . . ) invariant mass (gev/c−π + k lhcb (c) ) e v e n ts / ( . g e v /c . . . . ) invariant mass (gev/c+π − k lhcb (d) figure : invariant kπ mass spectra for bs,d → kπ events; the selection cuts are optimised for the best sensitivity to acp(bd → kπ) (plots a and b) and acp(bs → kπ) (c and d). plots a and c (b and d) show the k+π− (k−π+) invariant mass distribution. the main components of the fit model are also shown. m.pepe altarelli / nuclear physics b proceedings supplement ( ) – dependent analysis. this analysis is performed for the first time at a hadron collider, and the bs → k+ k− de- cay is studied for the first time ever. the preliminary results for the bd → π+π− channel are in agreement with the world average from the b factories. however, more data need to be analysed to be able to extract a measurement of γ from these decays. . c p violation in charm the charm sector is an interesting place to probe for the presence of np because cp violation is expected to be small in the sm. in particular, in singly cabibbo sup- pressed decays, such as d → π+π− or d → k+ k−, np could manifest itself through the interference between tree-level and penguin diagrams. lhcb has collected very large samples of charm: one in every ten lhc in- teraction results in the production of a charm hadron, of which - khz are written to storage and are available for offline analysis. in , lhcb has collected ap- proximately × tagged d∗± → (d → k+ k−)π± and × untagged d → k−π+ decays per pb− of in- tegrated luminosity and it has the world’s largest sample of two and three-body d(s) decays on tape. the difference in time-integrated asymmetries be- tween d → π+π− and d → k+ k− was measured using . fb− of data collected in [ ]. the flavour of the charm meson is determined by requiring a d∗± → (d → h+h−) π±s decay, with h = π or k, in which the sign of the slow pion πs tags the initial d or d . by taking the difference of the measured time-integrated asymmetries for π+π− and k+ k−, effects related to the d∗ production asymmetry and to the detection asym- metry of the slow pion and d meson in the final state cancel to first order, so that one can derive the differ- ence of the cp asymmetries, ∆acp. second-order ef- fects are minimised by performing the analysis in bins of the relevant kinematic variables. a nice additional advantage of taking this difference is that in the u-spin limit acp(k k) = −acp(ππ) for any direct cp viola- tion [ ], so that the effect is amplified. the final result is ∆acp = [− . ± . (stat) ± . (syst)]%. ( ) this result (subsequently confirmed by cdf [ ]) has generated a great deal of theoretical interest, as it is the first evidence for cp violation in the charm sector, with a significance of . σ. the difference in time-integrated asymmetries can be written to first order as ∆acp = [a dir cp(k + k−) − adircp(π +π−)] + ∆〈t〉 τ aindcp , ( ) ind cp a - . - . - . - . . . . . d ir c p a ∆ - . - . - . - . . . . . babar cp a∆ belle prelim. cp a∆ lhcb cp a∆ cdf prelim. cp a∆ lhcb Γ a babar prelim. Γ a belle prelim. Γ a figure : hfag combination of ∆acp and aΓ measure- ments [ ], where the bands represent ± σ intervals. the point of no cp violation ( , ) is displayed as a black dot; the ellipses show the two-dimensional % cl, % cl and . % cl with the best fit value as a cross. where adircp is the asymmetry arising from direct cp vi- olation in the decay, 〈t〉 the average decay time of the d in the reconstructed sample, and aindcp the asymmetry from cp violation in the mixing. in presence of a differ- ent time acceptance for the π+π− and k+ k− final states, a contribution from indirect cp violation remains. figure shows the hfag world-average combina- tion [ ] in the plane (aindcp, a dir cp). the combined data is consistent with no cp violation at . % cl. lhcb is currently completing the analysis of the full data sample and pursuing alternative strategies to verify the effect. in particular, an analysis is being fi- nalised in which the flavour of the d meson is tagged using the charge of the muon in semileptonic b decays; furthermore cp violation is searched for in charged d decays where there is no possibility of indirect cp vi- olation and a positive signal would indicate unambigu- ously the presence of direct cp violation. . conclusion this contribution has reviewed measurements of cp violation in charm and beauty decays performed by lhcb using up to . fb− of data collected in . in the b s system lhcb has obtained the world’s most pre- cise measurement of the mixing phase φs and the first direct observation for a non-zero value for ∆Γs. impor- tant milestones have been reached in the measurement of the weak phase γ both from decays at tree level and from those where new physics could contribute through loops. the large charm production cross-section at the lhc has allowed for a dramatic improvement in sensi- tivity to cp violating effects. during the run at m.pepe altarelli / nuclear physics b proceedings supplement ( ) – √ s = tev, another . fb− of data were collected, which will allow lhcb to increase the precision on the results presented here and pursue new analyses to un- derstand precisely the nature of cp violation in charm and beauty and hopefully find signs of new physics. acknowledgement i would like to thank the organisers of capri for their kind invitation to such a nice and fruitful meet- ing on a truly splendid island, my lhcb colleagues for providing the material discussed here and, in particular, tim gershon and vava gligorov for their careful read- ing of this article. references [ ] lhcb collaboration, “the lhcb detector at the lhc”, jinst s ( ). 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.pdf http://epjc.epj.org/index.php?option=com_article&access=standard&itemid= &url=/articles/epjc/abs/ / / _ _article_ / _ _article_ .html http://epjc.epj.org/index.php?option=com_article&access=standard&itemid= &url=/articles/epjc/abs/ / / _ _article_ / _ _article_ .html http://arxiv.org/pdf/ . v .pdf http://prl.aps.org/abstract/prl/v /i /e http://prl.aps.org/abstract/prl/v /i /e http://arxiv.org/abs/arxiv: . https://cdsweb.cern.ch/record/ https://cdsweb.cern.ch/record/ http://link.aps.org/doi/ . /physrevlett. . http://link.aps.org/doi/ . /physrevlett. . http://arxiv.org/abs/ . http://link.aps.org/doi/ . /physrevlett. . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://arxiv.org/pdf/ . .pdf http://arxiv.org/pdf/ . .pdf http://arxiv.org/pdf/ . v .pdf http://www.slac.stanford.edu/xorg/hfag/charm/ichep /dcpv/direct_indirect_cpv.html study of dimuon rare beauty decays with atlas and cms a. policicchio a and g. crosetti universita’ della calabria and infn cosenza september abstract. the lhc experiments will perform sensitive tests of physics beyond the standard model (bsm). investigation of decays of beauty hadrons represents an alternative approach in addition to direct bsm searches. the atlas and cms efforts concentrate on those b-decays that can be efficietly selected already at the first and second level trigger. the most favorable trigger signature will be for b-hadron decays with muons in the final state. using this trigger, atlas and cms will be able to accommodate unprecedentedly high statistics in the rare decay sector. these are purely dimuon decays, and families of semimuonic exclusive channels. already with f b− the sensitivity in the dimuon channels will be comparable to today world statistics. the strategy is to carry on the dimuon channel program up to nominal lhc luminosity. in particular the bs → µµ signal with ∼ sigma significance can be measured combining low luminosity cm− s− samples with those of one year of lhc operation at a luminosity of cm− s− . pacs. . .ce leptonic, semileptonic, and radiative decays – . .he decays of bottom mesons introduction rare leptonic and semileptonic b-decays, produced by fcnc transitions, are forbidden at the tree level in the standard model (sm). these decays occur at the lowest order only through one-loop “penguin” and “box” diagrams. the branching ratios of these decays are very small: from × − for rare radiative de- cay b d → k∗γ to − for rare cabibbo suppressed leptonic decay b d → e+e−. the careful investigation of rare b-decays is manda- tory for testing ground of the standard model and offer a complementary strategy in the search of new physics. the probing of loop-induced couplings provide means of testing the detailed structure of the sm at the level of radiative corrections. in particular, fcnc involv- ing b → s, d transitions and b → ll decays, provide an excellent probe of new indirect effects by yielding informations on the masses and coupling of the vir- tual particles running in the loops. in susy models, the branching fraction for b s(d) → µ+µ− has a strong dependence on tanβ. a precise measurement of such decays will allow to constrain the supersymmetric ex- tensions of the sm. to date the decay modes b s(d) → µ+µ− have not yet been observed. the current best upper limits on branching ratio come from d [ ] and cdf [ ] collab- orations and are . × − and . × − respectively at %cl. the searches for rare b decays at the b- factories cleo, belle and babar have not sensitivity to bs decays. a email: antonio.policicchio@cern.ch table . branching ratios in sm for rare b-decays with µ + µ − pair in final states. decay channel br. ratio ref. b s → µ + µ − . × − [ ] b + → k + µ + µ − . × − [ ] b + → k ∗+ µ + µ − ∼ − [ ] Λb → Λµ + µ − . × − [ ],[ ] b d → k ∗ µ + µ − . × − [ ],[ ] b s → φ µ + µ − ∼ − [ ],[ ] in the last years the b-factories babar and belle presented the first results for b → (k∗, k)l+l− branch- ing ratios and forward-backward asymmetry (af b ) in these rare semileptonic decays [ ],[ ],[ ] but still af- fected by large statistical errors. in this report we will pay our attention to the (semi)leptonic decays with µ+µ− pair in final state where atlas and cms can give a significant con- tribution. we discuss the simulation results and the perspectives of measurements. the branching ratios in sm of the decays studied can be found in table . theoretical description from the theoretical point of view, the b → q (q = s, d) transitions are described using the effective hamilto- nian a t l -p h y s- c o n f - - d ec em b er flavor physics contributed talk hef f = − gf√ vtbv ∗ tq ∑ i= ci(µ)oi(µ) ( ) in the form of wilson expansion (see e.g. [ ]). the set of wilson coefficients ci(µ) depends on the current model and contains the lowest order model contributions and perturbative qcd corrections. the scale parameter µ is approximately equal to the mass of b-quark (∼ gev ). this parameter separates the perturbative and nonperturbative contributions of the strong interactions. the nonperturbative contribution is contained in the matrix elements of basis operators oi(µ) between the initial and final hadronic states. for the calculation of these matrix elements it is necessary to use different decay-specific nonperturbative meth- ods: qcd sum rules, heavy quarks effective the- ory, quark models and lattice calculations. the ac- curacy in nonperturbative calculations depends on the method, but it is not less than %. the accuracy of the wilson coefficient for with nlo and nnlo qcd corrections [ ] is not greater than % if µ parameter ranges in [mb/ , mb]. in the sm the decay width of the rare muonic de- cays is: Γ (b q → µ+µ−) = g f α em π |v ∗tqvtb| · ( ) ( fbq mµc a ) √ m bq − m µ. this expression contains only one nonperturbative constant fbq . the value of this constant is known with high accuracy (about - %). furthermore the wilson coefficient c a in the nlo approach is not depen- dent on the scale parameter µ, and does not add any uncertainty in the theoretical predictions. trigger strategies for rare decays details of the atlas and cms experiments can be found in refs. [ , ]. . the atlas trigger atlas has a three level trigger system [ ] which re- duces the mhz bunch crossing rate to about hz of events to be recorded. the first level trigger (lvl ) is hardware-based and makes a fast decision (in . µs) about which events are interesting for further process- ing. coarse granularity informations from calorimeter and muon spectrometer are used to identify region of interest (roi) of the detector which contain interesting signals (high energy electrons, muons and taus and jets with large transverse or missing energy). the rois are used to guide the later stages of the trigger. after lvl the trigger rate will be reduced to less than khz. the high level trigger (hlt) is software-based and is split into two levels. at the level (lvl ) the full granularity of the detector is used to confirm the lvl decisions and then to combine informations from dif- ferent sub-detectors within the lvl rois. fast algo- rithms are used for the reconstruction at this stage and the rate is reduced to ∼ khz with an average time of execution of ∼ ms. at the level , the event filter (ef), the whole event is available and offline-like algo- rithms are used with better alignment and calibration informations to form the final decision. the rate is re- duced to hz with an execution time of ∼ s. . . atlas trigger for rare decays the b-trigger is expected to account for - % of the total trigger resources. the core of the b-trigger is the lvl muon trigger which is based on the measurement of the muon transverse momentum (pt ). the efficiency of the muon trigger is expected at about % at the plateau. the dimuon lvl trigger (two muons with pt above gev), used for rare decay selection, is expected to have a rate of about hz. the lvl dimuons will be confirmed at the lvl firstly in the muon system by means of the precision tracking chamber and then by combining muon and inner detector tracks. finally the two muons can be combined and mass cuts are applied. at the ef the tracks are refitted in the rois and vertex reconstruc- tion is performed. cuts are applied on decay length and invariant b-hadron mass. for b s → µ+µ− events containing two muons with pt > gev, efficiencies of - % are expected. . the cms trigger cms has a two level trigger [ ] which reduces the bunch crossing rate down to about hz for record- ing. the level- (l ) trigger uses muon detector and calorimeter informations and is hardware-based with an output rate of about khz and a latency of . µs. the hlt is software-based with the required hz output rate. it uses reconstruction algorithms similar to the offline with a mean execution time per event of about ms. to speed up reconstruction in the hlt, a partial track reconstruction is performed: the track resolution becomes asymptotic after - hits are used in the track fit. . . cms trigger for rare decays as in atlas, cms trigger for b events uses single and dimuon triggers. the l dimuon trigger has a low pt threshold of gev which ensures a high efficiency for events with two muons in the final state with a rate of . khz at × cm− s− . at the hlt the l decision will be confirmed using the full muon system and an improved momentum measurement with the tracker. primary vertex (pv) reconstruction is available from the pixel detector and also track reconstruction is per- formed in cones around the l muons using the partial a. policicchio and g. crosetti study of dimuon rare beauty decays with atlas and cms table . mass and proper time resolution obtained on the b s → µ + µ − signal montecarlo event sample for cms and atlas. experiment mass res.(gev) proper time res.(fs) atlas . cms . track reconstruction. the exclusive rare decay is then reconstructed and cuts on invariant mass, vertex fit quality and decay length are applied. muonic decays in atlas and cms as purely leptonic b-decays are theoretically very clean, they provide an ideal channel for seeking indirect hints of new physics effects. however they are very diffi- cult to observe because of their small branching ratio (see table ). most probably they will not be visible before the lhc data taking. atlas and cms will start sensitive measurements at cm− s− . even at high design luminosity ( cm− s− ) the trigger for b → µ+µ− decay is not problematic. a good background rejection is necessary for the signal selection. the main contributions to the back- ground [ ] come from the processes bb̄(bb̄bb̄, bb̄cc̄) → xµ+µ− with the muons originating mainly from semi- leptonic b and c quark decays. this background can be estimated extrapolating the tevatron data on heavy quark production to the lhc energies. it would be re- marked that both atlas and cms analysis are lim- ited by the statistics of the montecarlo background sample. the event selection relies on topological variables related to the pv, the muon candidates and the bs secondary vertex and is very similar in both the ex- periments [ , ]. simple cuts can be applied to dis- tinguish combinatorial background from the signal: – b-hadron invariant mass; – secondary vertex length and quality; – pointing of b-hadron momentum to pv; – track isolation. table summarizes the mass resolution and the proper time resolution obtained on the signal monte- carlo event sample for cms and atlas. the main result of the analysis is the expected number of signal and background events after f b− as summarized in table . this will allow to set strin- gent constraint on new physics models. figure shows the atlas expectation for b s → µ+µ− branching ratio as a function of the integrated luminosity (or equivalently as a function of the time). the sm expectation can be reached with ∼ sigma sig- nificance combining low luminosity cm− s− sam- ples with those of one year of lhc operation at the nominal luminosity of cm− s− . table . expected number of b s → µ + µ − and background events after fb − . experiment signal events bg events atlas . ± cms . + − fig. . atlas perspective of measurements for b s → µ + µ − branching ratio as a function of the integrated lumi- nosity (or equivalently as a function of the time). semimuonic decays in atlas thanks to the dimuon final state (see table ), the semimuonic decays, as the purely dimuonic ones, are easy to select at the trigger level. the observation of semileptonic decays give access to a number of ob- servables. the precise measurements of such observ- ables could give very interesting informations for new physics reach. af b is one of the most promising pa- rameters. the small branching ratios of semimuonic decays require a powerful background rejection. semileptonic decays with cc̄ resonances decaying into two muons represent an irreducible background source. a cut on dimuon invariant mass around nominal values for reso- nances removes this background. combinatorial back- ground arises from muons originating mainly from semi- leptonic decays of b and c quarks. specific decay chan- nels can represent background sources due mainly to hadron misidentification as muons, but their contribu- tion is expected to be less important than the previous two sources. the event selection [ , ] is related to topological variables: – vertex quality and invariant mass of the dimuon system; – displacement and quality of vertices and mass of the secondary hadrons; flavor physics contributed talk table . expected statistics for semimuonic decays events and background in atlas after fb − . decay signal events background events b + → k + µ + µ − < b + → k ∗+ µ + µ − < Λb → Λµ + µ − < b d → k ∗µ+µ− < b s → φ µ + µ − < fig. . forward-backward asymmetry for Λb → Λµ + µ − after fb− (see section ). – pointing of b hadron momentum to pv. statistics expected after three years of data taking at low luminosity ( fb− ) are summarized in table . the background level estimation is only limited by the low montecarlo statistics available at the moment. it should be pointed out that, thanks to the muon pair in the final state, semimuonic decays will be also studied at high luminosity, so that a larger statistics than those of table will be collected. the expected precision on af b after fb − is pre- sented on figure for Λb → Λµ+µ− decay. the three dots with error bars correspond to simulated data after offline analysis. upper point set corresponds to theo- retical sm predictions, and lower set corresponds to mssm predictions. the statistical error in the low dimuon invariant mass region is at level of %. the statistical errors expected on branching ratio measure- ments are at the level of . % and . % respectively for b → kµ+µ− and b → k∗µ+µ− decays. these errors on the branching ratio measurements are much smaller than the current experimental and theoretical ones. conclusions the results obtained for b s → µ+µ− by atlas and cms are comparable and promise an interesting startup analysis with the possibility of setting tight constraints on new physics models beyond the sm. the simulation studies show that atlas detector will be capable to extract signals of semimuonic b-decays and reach a good sensitivity to new physics beyond the sm. acknowledgments we would thank atlas and cms collaborations, and especially maria smizanska, sergey sivoklokov, pavel reznicek from atlas and christina eggel and urs langenegger from cms for their useful suggestions in the preparation of this work. references . the d collaboration, d� note -conf ( ) . the cdf collaboration, cdf public note ( ) . b. aubert et al. (the babar collaboration), phys. rev. d ( ) . a. ishikawa et al. (the belle collaboration), phys. rev. lett. ( ) . k. abe et al. (the belle collaboration), hep- ex/ ( ) . a. j. buras, phys. lett. b ( ) . a. ali et al., phys. rev. d ( ) . c. h. chen et al., phys. rev. d ( ) . t. m. aliev et al., nucl. phys. b ( ) . d. melikhov et al., phys. rev. d ( ) . d. melikhov et al., phys. rev. d ( ) . g. buchalla et al., rev. mod. phys. ( ) . c. bobeth et al., nucl. phys. b , ( ) . the atlas collaboration, cern-lhcc- - / ( ) . the cms collaboration, cern-lhcc- - ( ) . the atlas collaboration, cern-lhcc- - ( ) . n. nikitin et al., atl-phys-pub- - ( ) . p. reznicek, nucl. phys. b proceedings supplements ( ) . c. eggel et al., cms-an- - ( ) . a. policicchio and g. crosetti, acta phys. pol. b ( ) . a. policicchio and g. crosetti, atl-phys-pub- - ( ) www.cell-research.com | cell research npg research highlight pat: waking up a lazy sleeping beauty xiangdong fu , jianru zuo national center for plant gene research, institute of genetics and developmental biology, chinese academy of sciences, beijing , china. xdfu@genetics.ac.cn cell research ( ) : - . doi: . /cr. . ; published online may cell research ( ) : - . © ibcb, sibs, cas all rights reserved - / $ . www.nature.com/cr npg once upon a time, there was an unusual corn; and un- like its normal siblings, its stalk grew towards the ground rather than in an upward direction. the sleeping stature of the corn was portrayed in early s as “lazy” by jenkins and gerhardt [ ]. later, lazy appeared to be a fashion in the plant kingdom, found in rice, barley, tomato and several other species [ ]. these seemingly magic spell- chanted plants have drawn considerable interests of plant biologists and breeders for many decades. to breeders, the lazy phenotype, viewed as tillering or branching angles of stems (or termed as culms in crop plants), represents a key characteristic important for controlling photosynthesis efficiency and planting density, and thus a crucial factor in determining crop production [ ]. previous physiological studies suggested that the prostrate or lazy phenotype was attributed, at least in part, to the loss of gravitropism. for example, the rice lazy plants are ageotropic, whereas wild type (wt) plants are negatively geotropic [ ]. gravity plays a major role in plant morphogenesis by determining the directional growth of plant organs. upon germination, shoots grow upward, capturing light, and by contrast, roots penetrate the soil and grow downward, tak- ing up water and nutrients. plant tropisms have fascinated biologists for at least the last two centuries [ ]. the classical cholodny-went theory proposes that gravity-induced auxin (a plant hormone) redistribution across a gravistimulated plant organ is responsible for the gravitropic response [ ]. a unique feature of the auxin action is characterized by the polar auxin transport (pat) mechanism, involving two classes of specific proteins known as influx and efflux carriers [ ], which allows for a finely-tuned distribution of auxin in planta, thereby properly regulating a variety of cellular activities. over the past two decades, significant progress has been made in understanding the action of auxin and tropic growth of primary roots in arabidopsis thaliana. when presented with an alteration in the relative direction of the gravitational vector, the direction of root growth is changed, resulting in re-alignment of the direction of growth to that parallel with the new vector. in the gravi- tropic response, the peripheral reverse flow is diverted via redistribution of the cellular location of auxin efflux carriers [ ], leading to the differential auxin accumulation in the underside lateral root cap cells of gravitationally stimulated roots [ ]. the resultant auxin gradient is thought to extend to the distally located elongation region of the root, where relatively higher levels of auxin on the underside of the root inhibit cell growth. gravitropism is a key characteristic controlling photo- synthesis efficiency and planting density, one of the most important agronomic traits in determining crop production [ ]. thus the lazy phenotype has attracted much attention of the breeders. previous physiological studies on lazy mutants consistently pointed to a potential relationship with auxin actions [ ], however, the precise mechanism by which the auxin gradient affects gravitropic responses in crop remains unknown. a direct link between the rice gravitropic responses and the pat-mediated auxin redis- tribution is now revealed by jiayang li and colleagues in this issue of cell research [ ]. li et al. present convincing evidence showing that agravitropism in the rice lazy (la ) mutant is caused by an impaired pat. the la mutation renders the endogenous auxin, as monitored by a specific reporter gene dr -gus [ ], to distribute in an enlarged domain that somehow has moved downward to the basal part of the mutant coleoptiles. consistent with the above observation, in a pat assay, basipetal transport, but not acropetal transport, of radioactive indolyl- -acetic acid (iaa, a major bioactive auxin) in etiolated coleoptiles was substantially elevated in the la mutant compared to that in wild type. moreover, the gravity-stimulated lateral iaa transport between the lower and upper halves of the coleoptiles was also significantly impaired in the la cole- cell research | www.cell-research.com npg optiles. thus, la is involved in the regulation of the pat function to mediated distribution of iaa, through which it mediated the gravitropic responses in rice. the long struggling history of studies on crop gravitrop- ism was partly owing to the lack of molecular characteriza- tion of lazy genes. unfortunately, the rice la gene is located near the centromere in chromosome , a region difficult for genetic mapping due to the very low frequency of genetic recombination. nevertheless, the la gene was identified by li et al. [ ] through a tremendous effort by monitoring genetic recombination from over f mutant plants. la appears to be a grass-specific gene with no apparent homologs found in dicots. this raises an intriguing question: do dicots and monocots utilize dis- tinctive mechanisms in responding to gravitropic signals? the la gene encodes a protein of unknown function, which contains a putative transmembrane domain (tmd) and a putative nuclear localization signal (nls). la was shown to localize in both the plasma membrane and the nucleus in a tmd- and nls-dependent manner. this unique subcellular localization pattern suggests possible shuttling of the protein between the plasma membrane and the nucleus under different physiological conditions. interestingly, transgenic studies showed that the strength of the mutant phenotype was negatively correlated with the la expression level, strongly suggesting that la acts as a negative regulator of pat and thus the tiller angles dur- ing development. a new life started when the sleeping beauty was wo- ken up. the discovery made by li et al. [ ] resolves a long-lasting puzzle and represents a major breakthrough in the understanding of the cellular and molecular basis of gravitropism in crop plants. this study opens up new prospects for understanding the gravitropism in monocot plants, and therefore will feed plant biologists’ appetites for many years. not the least, crop-selection programs should benefit. reference jenkins m, gerhardt f. a gene influencing the composition of the culm in maize. iowa ag exp sta research bull ; : - . jones jw, adair cr. a “lazy” mutation in rice. j heredity ; : - . darwin c, darwin f. the power of movement in plants. london: john murray, . went fw, thimann kv, eds. phytohormones. new york: mac- millan, . friml j, wisniewska j, benkova e, et al. lateral relocation of auxin efflux regulator pin mediates tropism in arabidopsis. nature ; : - . ottenschläger i, wolff p, wolverton c, et al. gravity-regulated differential auxin transport from columella to lateral root caps cells. proc natl acad sci usa ; : - . li z, andrew hp, shannon rmp, james ws. rflp facilitated analysis of tiller and leaf angles in rice (oryza sativa l.). eu- phytica ; : - . godbole h, takahashi h, hertel r. the lazy mutation in rice af- fects a step between statoliths and gravity-induced lateral auxin transport. plant biol ; : - . li p, wang w, qian q, et al. lazy controls rice shoot gravit- ropism through regulating polar auxin transport. cell res ; : - . ulmasov t, murfett j, hagen g, guilfoyle tj. aux/iaa proteins repress expression of reporter genes containing natural and highly active synthetic auxin response elements. plant cell ; : - . pat: waking up a lazy sleeping beauty references effects have inadvertently been exploited by glass makers since at least the fourth century, for example to generate the colours used in stained-glass windows in medieval cathedrals. the scientific investigation of plasmonic effects began as early as with theoretical studies by arnold sommerfeld and experi- mental observations of plasmonic effects in light spectra by robert wood in . later that decade, j. c. maxwell garnett and gustav mie developed theories explaining the scattering effects by metallic nanoparticles. however, it was not until a number of theoretical studies in the s that a more complete understanding of spps was reached. the foundation for the systematic experimental study was then laid in by erich kretschmann and andreas otto, who devised methods to excite spps with prisms attached to metal surfaces. in the late s, the technologi- cal exploitation of plasmons began with the pioneering discovery by martin fleischmann and richard van duyne of significant enhance- ments in the raman scattering of the ‘diffraction limit’ of classical optics does not allow the localization of light into regions that are much smaller than its wavelength. as a result, the level of integration and miniaturization of photonic circuits is not even close to that achievable in electronics. the technology that might close this gap is known as ‘plasmonics’. plasmonic structures have beaten the diffraction limit, and led to advances in spectroscopy and sensing, imaging, cancer therapy, integrated nano-optics and solar cells, to name just a few. modern plasmonics started with a publication in by thomas ebbesen and colleagues, who observed a surprisingly efficient light transmission through a thin metal film with holes ten times smaller than the wavelength of light. additionally, more light was transmitted through the film than was incident onto the area of the holes. eventually, ebbesen was able to explain his observations with the properties of surface-plasmon polaritons (spps). spps consist of photons that interact with the surface motions of free electrons in metals. plasmonic light by molecules attached to a rough silver surface. this effect is explored for devices that detect molecular concentrations down to the single-molecule level. for applications in photonic circuits, the ebbesen discovery has led to efforts aimed at exploiting the highly localized nature of plasmons to guide light on the nanoscale. furthermore, a plasmon-based ana- logue to the laser, the spaser, could provide a source of coherent light below the diffraction limit. in addition, spps are exploited in a number of areas, such as meta materials (milestone ). similarly, plasmonic light concen- tration can not only enhance light absorption in solar cells, but also improve the efficiency of light- emitting devices. david pile, associate editor, nature photonics original research papers garnett, j. c. m. colours in metal glasses and in metallic films. philos. trans. r. soc. lond. a , – ( ) | mie, g. beirträge zur optik trüber medien, speziell kolloidaler metallosungen. ann. phys. , ( ) | kretschmann, e. & reather, h. radiative decay of nonradiative surface plasmon excited by light. z. naturf. a, – ( ) | otto, a. excitation of nonradiative surface plasma waves in silver by the method of frustrated total reflection. z. phys. , – ( ) | fleischmann, m., hendra, p. j. & mcquillan, a. j. raman spectra of pyridine adsorbed at a silver electrode. chem. phys. lett. , – ( ) | jeanmarie, d. l. & van duyne, r. p. surface raman spectroelectrochemistry. part i. heterocyclic, aromatic, and aliphatic amines adsorbed on the anodized silver electrode. j. electroanal. chem. , – ( ) | ebbesen, t. w., lezec, h. j., ghaemi, h. f., thio, t. & wolf, p. a. extraordinary optical transmission through sub-wavelength hole arrays. nature , – ( ) | hirsch, l. r. et al. nanoshell-mediated near-infrared thermal therapy of tumors under magnetic resonance guidance. proc. natl acad. sci. usa , – ( ) | bergman, d. j. & stockman, m. i. surface plasmon amplification by stimulated emission of radiation: quantum generation of coherent surface plasmons in nanosystems. phys. rev. lett. , ( ) | bozhevolnyi, s. i., volkov, v. s., devaux, e., laluet, j. y. & ebbesen, t. w. channel plasmon subwavelength waveguide components including interferometers and ring resonators. nature , – ( ) further reading raether, h. surface plasmons on smooth and rough surfaces and on gratings (springer verlag, ) m i l e s t o n e small and beautiful im a g e s o u r c e m i l e s t o n e s nature milestones | p h oto n s m ay © macmillan publishers limited. all rights reserved http://www.nature.com/milestones/milephotons/full/milephotons .html isaac newton may have long presided over the british library in the form of eduardo palaozzi’s vast sculpture at the library’s entrance, but only now is the london institution hosting its first science exhibition. beautiful science catalogues attempts to make sense of the world through visualizations from the seventeenth century to today, drawing on the vast archives of the united kingdom’s national library. on show are graphics from alchemist robert fludd’s work great chain of being — which attempts to explain the universe from stars to animals, vegetables and minerals — to a huge collection of modern circos diagrams used to visualize genetic information and highlight relationships between species. “infographics are now a staple of every newspaper in the country. in many ways this seems like a new phenomenon,” says curator johanna kieniewicz. “what i was really keen to show is that it actually has a very interest- ing and rich history.” the graphics have a many-layered power. “the visual representation of science can i n c re a s e b o t h t h e engagement of fel- low researchers [and] t h e p u b l i c ,” s a y s kieniewicz. perhaps the exhi- bition’s most famous expression of this is nightingale’s rose, from the s. a pioneer of modern medicine, florence nightingale demonstrated the value of improved hospital hygiene by showing that during the crimean war, more british sol- diers died as a result of poor sanitation in hospital than from enemy action. the image she drew to illustrate this point, says kienie- wicz, has “changed science, changed the way in which things are done”. less transformative but no less impressive is william farr’s failed – attempt to determine the cause of a cholera epidemic. his huge temperature and mortality of lon- don plots these two variables in circular graphs. farr’s contemporary, john snow, was more successful in using epidemiologi- cal mapping to pin cholera down as a water- borne disease; yet farr’s diagram stands as a monument to the difficulties of trying to tease causation out of huge data sets. farr eventually came around to snow’s views, in part thanks to snow’s data presentation. beautiful science shows that good data presentation is timeless. witness luke howard, the meteorologist who named the i n f o g r a p h i c s truth is beauty daniel cressey views the british library’s first science exhibition — a celebration of scientific illustration. beautiful science: picturing data, inspiring insight british library, london. until may . nature.com for a video about the exhibition, see: go.nature.com/cvy r popular with cool-climate neander- thals occupying the mountain ranges of eurasia. certain regions loom large in the improbable primate as launch pads for nature’s experiments in human evo- lution: northeast africa and arabia (dubbed “middle earth”, but free of hobbits), the mountain chains of main- land asia and the continental shelves of southeast asia, exposed when sea levels fell during each ice age. in this largely descriptive account of human bio geography, finlayson paints with a broad brush. defying convention, he lumps all hominins in the past . mil- lion years into a single species, homo sapiens. this will be too large a lump for most palaeoanthropologists (and me) to swallow. but his focus on hominin lineages — rather than individual spe- cies — has some merit, given that genetic evidence has arisen in recent years of ancient admixture between early mod- ern humans, neanderthals and denis- ovans, and of gene flow into denisovans from an unknown archaic hominin. an admirable feature of finlayson’s hypothesis is its amenability to scientific testing. further empirical data from fos- sils, artefacts and environmental records will certainly be valuable, as might a more nuanced treatment of individual sites. i would have welcomed more informa- tion about the chronology of these sites (which number more than ), and the processes of burial, weathering and pres- ervation that affected them over time. sites close to water and in caves can be overrepresented in surveys, because their preservation potential is often higher than that of desert sites. ecological models are another avenue worth exploring. mathematical mod- els that examine foraging patterns and responses to habitat fragmentation in space and time, and simulations of alter- native hypothetical scenarios, can help to illuminate what may have happened in the past. such models could indicate which combinations of factors were likely to have had the greatest effect on hominin evolution. multiple selective pressures have been in play over the past million years and across the six inhabited con- tinents, so untangling these interactions will be no easy task. the improbable pri- mate provides a useful starting point for this next great challenge. ■ richard g. roberts is australian research council laureate fellow and director of the centre for archaeological science at the university of wollongong, australia. e-mail: rgrob@uow.edu.au books & artscomment | n a t u r e | v o l | m a r c h ocean currents swirl and eddy in a visualization of nasa satellite data, on show at the british library. © macmillan publishers limited. all rights reserved three basic cloud types — cirrus, cumu- lus and stratus. his diagram of the weather recorded in at his home in tottenham, north london, sits next to a strikingly similar display of weather data from . the latter is given a modern twist through an overlay of social-media commentary by design firm cleverºfranke of utrecht, the netherlands. as science generated more complicated data, the methods needed to visualize them also became more complicated. evolution- ary theorist jean-baptiste lamarck’s table of the relationships between mammals, fish, reptiles, crustaceans and other animals can be understood easily by anyone with the most basic knowledge of french; much more parsing is needed for an avian tree of life published in nature in that sits next to it. the exhibition reveals how seriously sci- entists need to take data presentation to con- vey meaning. most of the pieces displayed were arduously plotted and coloured by hand. says kieniewicz of today’s spreadsheet tools for chart production: “they make it too easy. you don’t end up putting much thought into graphs.” modern scientists, although liberated from painstaking drafting and shading, can gain from thinking hard about their audi- ence, and about precisely what and how they want to communicate. a graph in a research paper today could be at the british library in years hence, forming part of what kienie- wicz calls scientists’ “visual legacy”. science, the exhibition reminds us, is all about beautiful ideas. the trick is finding the aesthetic that maintains both meaning and elegance. ■ daniel cressey is a reporter for nature in london. a garden of marvels: how we discovered that flowers have sex, leaves eat air, and other secrets of plants ruth kassinger william morrow ( ) after ‘murdering’ a kumquat tree through hard pruning, ruth kassinger set out to understand plant physiology through the history of botany. in this scientific wonderland, we encounter robert hooke’s exquisite drawings of plant structure in micrographia ( ); arsenic-gobbling brake ferns; and the single eukaryote that, . billion years ago, engulfed a cyanobacterium and spawned the multitude of chloroplasts that made life on earth possible. barbara kiser the rise of superman: decoding the science of ultimate human performance steven kotler new harvest ( ) in extreme athletics, ‘redefining the possible’ is happening at an unprecedented rate. in this high-octane study, steven kotler explores ‘flow’, a neurochemically rich state in which cognitive and physiological processes mesh. the stupendous physical feats of the late ski-base jumper shane mcconkey and others are riveting. equally surprising is what we know of flow science, such as how the brain’s superior frontal gyrus deactivates to speed decision-making — and how ‘bliss addiction’ can result from too much exposure to flow states. the galapagos henry nicholls profile books ( ) from the plangent cries of blue-footed boobies to the plash of swimming iguanas, the galapagos islands remain pristine — but for how long? in this natural and human history of darwin’s living laboratory, henry nicholls surfs from geology, oceanography and marine biology to resident land species, not least the burgeoning population of homo sapiens. throughout, he intertwines key accounts such as darwin’s inspired musings on geological uplift and the piscine encounters of pioneer diver william beebe. one for the scientific islomane with a sense of the bigger picture. visions of science: books and readers at the dawn of the victorian age james secord oxford university press ( ) angst over scientific literacy is nothing new, notes james secord. the political unease and religious turmoil in early victorian britain prompted john herschel and fellow scientific utopians to urge a corrective: the dissemination of ‘useful’, or scientific, knowledge across society. as secord shows, access to texts such as charles babbage’s searing reflections on the decline of science in england helped to foment an intellectual revolution in step with those in industry and modern science. governing marine protected areas: resilience through diversity peter j. s. jones routledge ( ) marine protected areas, or mpas — ocean zones limiting human activity — cover little more than % of the world’s oceans, despite an internationally agreed target of % by . and thousands of those that do exist are little more than ‘paper parks’, many scientists have found. entering these choppy waters is geographer peter jones, who shows, through some case studies, how and how not to govern mpas effectively. jones compellingly concludes that a diversity of incentives, from economic to social, is as essential as the diversity of the ecosystems mpas are designed to protect. n a s a /s v s m a r c h | v o l | n a t u r e | books & arts comment books in brief © macmillan publishers limited. all rights reserved infographics: truth is beauty references international journal of new developments in engineering and society issn - vol. , issue : - , doi: . /ijndes. published by francis academic press, uk - - research on the adaptability of ecological building in construction of beautiful village peng wenfei wenzhou vocational & technical college, china abstract. under the background of sustainable development, ecological architecture is a kind of building system developed gradually under the condition of the continuous development of social factors such as economy, culture, science and technology, the deterioration of environment and the continuous improvement of people's living conditions. because of the huge number of buildings, it has a significant impact on resources and environment. similarly, if ecological buildings want to effectively improve resources and environmental problems, they must be constructed in large quantities. human beings themselves are also moving towards high quality and high standard of life, which are two aspects of contradiction. strengthening the construction of ecological buildings is one of the effective ways to solve the contradiction. the scientific concept of implementing architectural design is ecological building, saving energy, saving land, comprehensive consideration, and overall planning, adding luster to the beautiful rural construction. the use of local existing materials and conditions, the formation of ecological architecture with local characteristics, traditional architecture and the current concept of ecological architecture are consistent, there is a certain degree of interaction between the two. strategies and ways to improve the adaptability of ecological building technology, hope to provide some help for the improvement of ecological building technology adaptability. keywords: beautiful countryside; construction; ecological architecture . introduction eco-architecture is sometimes called green building and sustainable building. in the s, paul sollery, an italian-american architect, put forward the concept of ecological architecture, that is, to understand architecture from the perspective of ecology and apply the theory of ecology to architecture [ ]. use as little resources and economic consumption as possible to achieve the design objectives of the building. economization mainly includes saving resources and energy. rural area is a typical complex ecosystem. the coordination among its components, the international journal of new developments in engineering and society issn - vol. , issue : - , doi: . /ijndes. published by francis academic press, uk - - regeneration of material cycle, the low consumption of energy transfer, the optimum utilization of resources and the synergistic symbiosis between man and nature [ ]. because traditional rural development systems and architectural models are unsustainable, polluting the environment and degrading the quality of life, architects are inspired by green culture [ ]. in the long-term survival process, organisms can improve their various functions and adapt to changes in the natural environment in order to survive. if a building project can have some properties similar to those of a living organism, it can adapt well to the environment. the countryside has gradually been marginalized, and it has only been taken into consideration in recent years, and the beautiful vision of “beautiful villages” has been proposed. arrange and organize the relationship between the building and other related factors, so that the building and the environment become an organic combination, with good indoor climatic conditions and strong bio-climatic adjustment ability [ ]. in the design process of rural ecological buildings, the actual situation of the countryside should be fully taken into account, starting from the economy, practicability, practicability and suitability. eco-architecture takes resources and pollution as its basic elements, and tries its best to protect the natural environment and improve the health of users without reducing the use function of buildings [ ]. in order to build an ecological village, we must attach great importance to the protection of natural landscape, historical and cultural relics landscape, especially the diversity of natural species, so as to preserve the unique features in the process of construction [ ]. energy-saving ecology will reduce the impact of the building itself on the environment, make the building itself an independent operation of life, with its own metabolism, and even improve the surrounding environment. areas that need to be preserved and revamped are separated, systems that need to be protected, revamped and constructed but are not available at the base status quo [ ]. as one of the concrete measures to achieve sustainable development, ecological buildings have the responsibility to contribute to the continuation of local culture and the realization of global cultural diversity. its means include: the protection and inheritance of traditional neighborhoods, the characteristics of local settlements; the continuation of appropriate traditional and local construction techniques. ensure that construction projects are more coordinated with the natural environment. ecological building technology can imitate creatures from different angles, whether it is biological form, structure or movement mode, can be applied to architectural design [ ]. . basic characteristics of ecological architecture eco-architecture not only creates a small environment for people living in it to satisfy their physiological and psychological needs (such as comfortable temperature, light environment, humidity, sound environment and good air quality). at the same time, we should also consider the relationship with the local natural environment. after the site selection is reasonably completed in environmental design, the climate characteristics should be analyzed, the surrounding environment should be designed, and the climate conditions should be improved. in order to effectively correct the shortcomings of traditional buildings and improve the resources and environment, international journal of new developments in engineering and society issn - vol. , issue : - , doi: . /ijndes. published by francis academic press, uk - - ecological buildings must be constructed and used in large quantities. only in this way can we achieve the goal that ecological buildings want to achieve. in the design process, the important principle to follow is to maximize efficiency. at the same time, some very mature process technologies in the design field are just the technologies needed for ecological buildings. if the construction industry can adhere to the concept of “ecology” in the construction of beautiful countryside, the environmental resources and ecological problems in the region will be greatly improved. in the construction of beautiful rural ecological architecture, we must first understand the natural process of the environment in which the village is located fundamentally, make full use of the natural resources and conditions in the development and construction of the village, and make the artificial system and the natural system coordinate and harmonize. because of the complex function space and the use of the underground floor, the comfort of some space can not meet people's requirements, which needs to be solved by consuming huge energy, mechanical ventilation, lighting and central air-conditioning system. secondly, for some relatively developed economies, the promotion of high-tech ecological buildings will not only establish a good example, but also play a huge role in publicity and promotion. transplanted according to ecological requirements, with the application of high-tech as the main body, even if some traditional techniques are used, it is based on scientific analysis and research, and is realized by advanced materials and techniques. participate in the construction process of ecological buildings. this kind of multi-level and multi-faceted coordination and cooperation must have a unified evaluation and evaluation standard, which can reach consensus among all parties and implement this consensus. to truly meet the needs of rural buildings, and to promote the value of construction. in the design of rural ecological architecture, we should make full use of local materials and create reasonable ecological value in a simple way of technical construction. let the building and the natural environment combine into an organic whole, and at the same time should have good indoor climate conditions to make users live more comfortable and healthy. structural components should be standardized and serialized. green ecological building technology is used to ensure that the life cycle cost of construction projects is reduced. in the design process, attention is paid to the selection of building technology, materials, natural ventilation and landscape design. the imitation of ecological architecture design is not the artistic needs such as modeling, nor the expression of cultural concepts. it is mainly to learn the adaptability of biological, machine and traditional architecture to the changes of the external environment, the rationality and efficiency of the use of resources and energy, etc. . according to the climatic characteristics of the region, select appropriate building materials and structural forms, adapt to local conditions, select materials locally, and reduce energy consumption in material transportation. in response to the requirements of ecological green design, we must pay more attention to whether it has a high degree of safety in the choice of building materials, including whether it has radiation and has certain harm to the human body. establish international journal of new developments in engineering and society issn - vol. , issue : - , doi: . /ijndes. published by francis academic press, uk - - and improve the building environmental assessment system to supervise the built environment to achieve optimal configuration of the building and environment. .application of ecological architecture whether a new building meets the requirements of the ecological environment requires a corresponding evaluation system to evaluate it and determine its good standards. comprehensive and scientific testing for the related characteristics of materials such as density, strength, heat transfer coefficient, durability and so on is carried out to ensure that these indicators meet the design requirements. architects play a major role in organizing and coordinating, and many structures and details must be designed strictly according to the results of scientific calculations. also consider the need to be consistent with the aesthetics of the building facade. repeated photovoltaic modules will form a certain rhythm on the facade of the building, and will create new technical features for the facade of the building facade photovoltaic components. when planning the building layout, in order to increase the lighting and improve the ventilation conditions, you can change the orientation of the building to design the building. try to let the natural wind swirl indoors, so that the ventilation effect will be better. in the design and construction of building infrastructure, more emphasis is placed on the application of local resources and recycled materials. rural ecological building construction should also follow this principle, the same mode will affect and destroy the ecological balance of the region. only by combining with the characteristics of the region, the construction of regional ecological buildings can be integrated into the ecological balance. greening and covering the ground can cool the surrounding environment as high as trees can form shade on the ground, reduce heat absorption on the ground, purify the air and improve the oxygen content of the air. at the same time, technology is also developing dynamically, and technology between different levels will be transformed with the development of social and economic technology. any kind of high technology, after long-term industrial development, low-temperature radiant heating and cooling efficiency is high, the temperature is uniform, and the system does not occupy the indoor space, will not damage the overall appearance of the building, basically can achieve no wind, no noise. improve the utilization rate of regenerative clean energy, thereby reducing the emission of soot and sulfur dioxide, purifying the air, creating a sustainable, zero-energy, zero-pollution, and affordable low-carbon residential image, and truly achieving energy-saving and emission reduction targets. to ensure the continuous development of china's ecological building technology level, and continue to promote and apply high-level ecological building technology, effectively reduce capital investment in construction projects and promote the development of ecological building technology. scientific planning, rational layout, saving arable land and developing economy are the keys to building well-off residential buildings in beautiful countryside. when planning the well-off residential buildings in the new countryside, we should combine the distribution of land resources and try to choose the safe geographical international journal of new developments in engineering and society issn - vol. , issue : - , doi: . /ijndes. published by francis academic press, uk - - position which occupies less arable land. it is necessary to establish ecological indicators for construction projects. on this basis, conceptual design, compilation of performance indicators of ecological buildings, and selection of reasonable technology for investment and effect comparison, the economic and technological development speed is still at a relatively low level. therefore, in the study of the adaptability of ecological technology, we should also formulate the development strategy of ecological building technology which is more in line with the actual situation of our country. the materials and energy input in the rural production process are maximized, that is, the waste of resources and energy is minimized, and the waste discharged is also minimized, and the waste can naturally penetrate into nature. the relationship between biological forms and functions and the relationship between the form and function of architecture and the principles and architectural principles of the living body itself. these mutually comparable characteristics determine that buildings can benefit from biological learning. we will strive to make effective use of the existing natural ecological conditions in the environment, and combine the natural climatic conditions of the area where the base is located and the small environment unique to the building base for site design and architectural design. . conclusion in this paper, the adaptability of ecological architecture in the construction of beautiful countryside is studied, which is based on the principle of ecological design and aims at human survival and comfort needs. to maximize the utilization of energy and materials, to minimize environmental pollution during construction and use, site selection, resource utilization and building forms. in the design of rural ecological architecture, we should fully tap the connotation of local traditional construction technology, and strive to find the combination of traditional construction technology and modern architecture in line with regional characteristics. a complete ecosystem can fundamentally change human living space and optimize environmental quality. in the acquisition process of eco-building technology, we absorb the operating rules of life system and apply these laws to the design of construction projects, so that they gradually develop into eco-building technology. in the architectural design, the treatment of aquaculture and domestic garbage should be comprehensively considered to reduce environmental pollution. taking the scientific principles of ecology as the guiding ideology, the created architectural space environment is a harmonious and organically unified building site between man and nature. it is necessary to make rational and effective use of land resources and maintain the sustainable use of land and water resources. appropriate application of ecological building technology to buildings will inevitably enable people, architecture and ecological environment to achieve harmony and unity on the basis of ensuring regional culture. references international journal of new developments in engineering and society issn - vol. , issue : - , doi: . /ijndes. published by francis academic press, uk - - [ ] chen f s, yavitt j, hu x f ( ). phosphorus enrichment helps increase soil carbon mineralization in vegetation along an urban-to-rural gradient, nanchang, china. applied soil ecology,vol. p. - . [ ] bixia c, yuei n, takakazu u ( ). planted forest and diverse cultures in ecological village planning: a case study in tarama island, okinawa prefecture, japan. small-scale forestry, vol. ,no. , p. - . [ ] farzaneh e g, mahdieh p ( ).studying the necessity of designing buildings with ecological architecture approach in ecosystem of wetlands international miankaleh. pedobiologia,vol. ,no. - , p. - . [ ] kocsis, tamás ( ). is the netherlands sustainable as a global-scale inner-city? intenscoping spatial sustainability. ecological economics, vol. , p. - . [ ] brock m t, lucas l k, anderson n a, et al ( ). genetic architecture, biochemical underpinnings and ecological impact of floral uv patterning. molecular ecology, vol. ,no. , p. - . [ ] wilson r l, wilson g g, usher k ( ) . rural mental health ecology: a framework for engaging with mental health social capital in rural communities. ecohealth, vol. ,no. , p. - . [ ] evans b s, ryder t b, reitsma r, et al ( ). characterizing avian survival along a rural‐to‐urban land use gradient. ecology, vol. ,no. , p. - . [ ] bakker m m, alam s j, van dijk j, et al ( ). land-use change arising from rural land exchange: an agent-based simulation model. landscape ecology, vol. , no. , p. - . wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ the appraisal of facial beauty is rapid but not mandatory copyright psychonomic society, inc. facial attractiveness is considered a key feature in so- cial interactions, and one that plays a major role in peer and mate choice (etcoff, ). consequently, a large bbody of research has focused on the physical characteris- tics that render a face attractive. some major factors that have been suggested are the averageness of a face (lang- lois & roggman, ; rhodes & tremewan, ), its symmetry (rhodes, proffitt, grady, & sumich, ; but see zaidel & deblieck, ) and familiarity (see, e.g., peskin & newell, ; rhodes & tremewan, ), and hormone-dependent facial features (see thornhill & gangestad, , for a review). however, research has only recently begun to investigate the neuronal processes underlying the appraisal of facial attractiveness in the mind of the beholder. neuroimaging studies have reported several brain areas that are differentially responsive to attractive and nonat- tractive faces. typically, reward- and emotion-related areas—such as the orbitofrontal cortex, basal ganglia, and amygdala—have been shown to be activated by facial at- tractiveness (aharon et al., ; kampe, frith, dolan, & frith, ; kranz & ishai, ; nakamura et al., ; o’doherty et al., ; winston, o’doherty, kilner, per- rett, & dolan, ). these effects may be related to the aesthetic aspects of facial beauty, because they are inde- ppendent of the gender of the viewers or of the persons depicted. in addition, a component of attractiveness due to sexual attraction or reproductive fitness has been sug- gested (see, e.g., senior, ) that is sensitive to gender or sexual orientation. across different imaging studies, the brain areas specifically responding to the facial attrac- tiveness of potential mates are quite diverse, ranging from the superior temporal sulcus (o’doherty et al., ) to the basal ganglia (specifically, nucleus accumbens; aha- ron et al., ) to the medial orbitofrontal cortex (ofc; kranz & ishai, ). interestingly, recent findings have demonstrated enhanced ofc activation to faces of po- tential partners, including same-sex mates in homosex- ual participants, which it has been suggested reflects the higher reward value of these faces, irrespective of their reproductive fitness (ishai, ). although everyday experience suggests that the ap- praisal of attractiveness is a fairly rapid process, only a few objective data have been collected on this issue. a recent masking study by olson and marshuetz ( ) showed d that attractiveness is perceived even if faces are exposed for only a very short time, suggesting that attractiveness is assessed rapidly and on the basis of minimal visual infor- mation. more direct evidence on the time course and locus of action of attractiveness may be gained from event- drelated brain potentials (erps). the few pertinent erp studies have indicated two subsequent intervals during which attractive- ness modulates brain processes. the most robust finding is a modulation of the so-called late positive complex (lpc). x johnston and coworkers conducted two studies involving the presentation of facial portraits that varied in specific attractiveness-related features (e.g., chin length; johnston & oliver-rodríguez, ; oliver-rodríguez, guan, & johnston, ). faces rated as attractive elicited larger lpc amplitudes at parietal and central electrodes between and msec after target onset. this finding is in line fwith other reports of lpc increases for various types of the appraisal of facial beauty is rapid but not mandatory annekakk thrinaa schachtaa , kakk tjaa ajj wa erheid, and werner sr ommer humboldt university at berlin, berlin, germany facial attractiveness is an important source of social affective information. here, we studied the time course and task dependence of evaluating attractive faces from a viewer’s perspective. event- related brain potentials (erps) were recorded while participants classified color portraits of unfamiliar persons according to gender and facial attractiveness. during attractiveness classification, enhanced erp amplitudes for attractive and nonattrac- tive faces relative to faces of intermediate attractiveness were found for an early component around msec and for the late positive complex (lpc). whereas lpc enhancement conforms to previous studies employing various types of affective stimuli, the finding of an early effect extends earlier research on rapid emotion pro- cessing to the dimension of facial attractiveness. dipole source localization of this early erp effect revealed a scalp distribution suggesting activation of posterior extrastriate areas. importantly, attractiveness-related modu- lations of brain responses were only marginal during the gender decision task, arguing against the automaticity ppof attractiveness appraisal. cognitive, affective, & behavioral neuroscience , ( ), - doi: . /cabn. . . a. schacht, schachta@hu-berlin.de facialacial attractivenessttractiveness of pathologically deformed (szondi) faces (pizzagalli et al., ) or artificially distorted portraits (halit et al., ). in sum, it appears that the attractiveness of faces may be ap- praised rather rapidly, with a time course that is comparable to the processing of other affect- related dimensions in both faces and nonface objects, but as yet the evidence is scarce and requires more direct corroboration. the primary aim of the present study was to investigate whether faces of varying attractiveness would elicit dis- sociable erps and at which points in time such a modula- tion would occur. to this end, it seemed important to take into account the interindividual variability of attractive- ness judgments. although attractiveness can be related to certain common perceptual features, as mentioned above, there is also considerable interindividual variance in judg- ments of physical attractiveness (feingold, ). this fact was accounted for in the present study by sorting the stimuli according to the participants’ individual ratings as well as by an additional, item-specific analysis. a further aim of the study was to investigate whether attractiveness appraisal is mandatory whenever a face is seen, or whether instead it depends on the viewer’s task or processing strat- egy. therefore, erps were measured not only during at- tractiveness ratings but also while participants performed a gender decision task on the faces. method participants eighteen students ( female, male; mean age . . years) contributed data to the experiment. three additional data sets were discarded because of technical problems or excessive erp artifacts; all of the remaining participants were right-handed and reported normal or corrected-to-normal vision. the study was conducted in accordance with the declaration of helsinki, and all participants gave informed consent to participation in the study and were com- pensated with course credit or € /h. stimuli the stimulus set consisted of color portraits of different young adult persons ( female, male). the persons depicted had been recruited through several model agencies, and the portraits were taken by a professional photographer under identical studio conditions. the portraits were standardized with respect to frontal view and frontal gaze direction, resolution ( dpi), and lighting. accessories (e.g., jewelry or hair clips) were avoided, makeup was restricted to eyeliner, and no clothes were in view. the original por- traits were reframed to ensure identical display windows and were placed in front of a standardized light gray background. all models had been informed about the photographer’s cooperation with the authors of this study and had given written consent for the use of their portraits for scientific purposes. to control for a possible impact of facial affect on attractiveness judgments, we conducted a computer-assisted preexperimental rat- ing of emotional expression, which included students ( female, male; mean age . . years) who did not overlap with the erp study. on a scale from (very happy) to (very angry), the mean emotion ratings of the portraits ranged between . and . (m(( . , sd . ). mean itemwise attractiveness ratings in the present experiment were moderately correlated with these emotion ratings (r . , p . ). procedure the participants were seated in a dimly lit, sound-attenuated, and electrically shielded room. the portraits were presented on a com- emotional stimuli, including affectively connotated words (fischler & bradley, ; schacht & sommer, ), scenic pictures (cuthbert, schupp, bradley, birbaumer, & lang, ; schupp, junghöfer, weike, & hamm, ), and faces with emotional expressions (e.g., schupp, Öhman, et al., ; schutter, de haan, & van honk, ; werheid, alpay, jentzsch, & sommer, ). recently, we investigated erp correlates of apprais- ing facial attractiveness by comparing attractive and less attractive faces that were preceded by various types of primes (werheid, schacht, & sommer, ). in line with the above-mentioned literature, we found larger lpc amplitudes to attractive than to less attractive faces, but also an earlier effect around msec, consisting of an enhanced right-occipital negativity and left-frontal posi- tivity for attractive faces relative to less attractive faces. both erp effects occurred independently of whether the actual stimuli corresponded with the primes. although these findings were the first to demonstrate attractiveness- related erp effects prior to the lpc, they were in line with several previous studies on emotional face process- ing that had also revealed erp effects prior to the lpc. for example, threatening facial expressions compared with neutral ones evoked posterior negativities at similar latencies between and msec after stimulus presen- tation (balconi & pozzoli, ; schupp, Öhman, et al., ; schutter et al., ). Öhman and mineka ( ) interpreted these findings as the facilitation of automatic processing of fear-inducing stimuli by a “fear system” that enables rapid flight reactions, and thereby subserves sur- vival. in a recent study, we found an enhanced negativity at posterior electrode sites to happy as compared with neu- tral faces at around msec (schacht & sommer, ). importantly, this early effect showed a scalp distribution not corresponding to the n , but instead similar to that found in affective picture processing (see, e.g., schupp, junghöfer, weike, & hamm, a, b, ; schupp et al., )—that is, the early posterior negativity (epn; see, e.g., schupp et al., a, b) that has been re- lated to spontaneous attention capture by emotionally sa- lient stimuli (e.g., schupp et al., ). complementary evidence comes from a study by eimer, holmes, and mc- glone ( ), who reported a facial expression effect dur- ing the n time range but with a scalp distribution that differed from the n . interestingly, this effect appeared only when attention was allocated to emotional expres- sion, indicating a strong task dependency of this effect. whereas the studies above focused on emotional facial expressions, several findings have indicated that facial at- tractiveness is also appraised relatively quickly. first, the above-mentioned study by johnston and oliver-rodríguez ( , figure ) appeared to show an early effect around msec for attractiveness, which unfortunately was not analyzed. second, two further studies revealed even ear- lier erp modulations, possibly related to attractiveness ap- praisal, either for the p time range (pizzagalli, regard, & lehmann, ) or for the p and subsequent n and p components (halit, de haan, & johnson, ). however, these studies were not conclusive about the spe- cific role of attractiveness because they used either portraits sschachtchacht, w, werheid,, andand ssommerommer portraits. these categories included mean rating values from . to . for attractive, . to . for intermediate, and . to . for nonattractive faces. the erp responses to each portrait for a given participant were assigned to one of these categories, depending on the average attractiveness rating of the participant for this portrait. thus, in this type of analysis, the erps to a given portrait elicited in different participants could be assigned to the same or to different attractiveness categories, depending on the participants’ individual attractiveness ratings. the erps from the attractiveness rating condition were analyzed in two further ways: an idiosyncratic five-bin analysis and an itemwise analysis. the five-bin analysis was performed for two reasons. first, it allowed for a more fine-grained analysis of attractiveness effects. second, idiosyncratic distributions of ratings—for example, biases toward one of the poles or toward the middle of the scale—could be considered to a greater extent. in this analysis, the rating distribution of each participant was partitioned into five bins that contained ap- proximately equal numbers of the rated stimuli. erp averaging then took place according to these five idiosyncratic bins. finally, the relationship between emotional significance and pos- sible erp effects was analyzed at the item level. erps and attrac- tiveness ratings were averaged for each item across the three presen- tations per participant as well as across the participants. erp segmentation was based on visual inspection of measures of global field power (gfp; lehmann & skrandies, ) and global map dissimilarity (gmd; brandeis, naylor, halliday, callaway, & yano, ). gfp reflects the overall erp activity across the scalp at any given moment. gmd shows the dissimilarity between scalp topographies of adjacent time points and demarcates the borders between periods of relatively invariant topographies. mean amplitudes were assessed separately for each task, using repeated measures anovas including the factors attractiveness and electrode site. by definition, the average reference sets the mean value of the erp amplitude to zero across all electrodes within a given condition. therefore, in these anovas, only effects in interac- tion with electrode site are meaningful. the huynh–feldt correction was applied to adjust the degrees of freedom of the f ratios. pleasef note that all of the repeated within-subjects anova measures will be reported with corrected degrees of freedom as well as corrected p values. to analyze whether any interactions of the experimental conditions with the electrode factor related to differences in ampli- tude, anovas with gfp measures were calculated. for pairwise comparisons, the alpha levels were bonferroni corrected. dipole source modeling of the early attractiveness effect was per- formed with the brain electromagnetic source analysis program (besa, version . ; scherg & berg, ) with a four-shell spheri- cal head model (i.e., brain, bone, cerebrospinal fluid, and scalp). resultsll performance according to the three attractiveness categories based on the distributions of mean rating values, % of all facial stimuli were classified as nonattractive and % as attractive; the remaining % were of intermediate attractiveness. the mean rts (with sds in parentheses) during gender classification of the attractive, intermedi- ate, and nonattractive faces were, in order, . ( . ), . ( . ), and . ( . ) msec. anovas did not in- dicate any effects of attractiveness and portrait gender on the speed of gender classification (f(( sff ). as expected, rts during the -point attractiveness ratings, which re- quired mouse movements and clicks, were much longer than those during dichotomous gender classifications, but the rts did not differ across the three attractiveness bins (m(( smm , . , , . , and , . msec; f ). puter screen at a distance of cm and a size of . cm. the erp experiment consisted of two parts, gender decision and attrac- tiveness rating. during the first part of the experiment, participants classified the portraits according to gender by pressing the left or right mouse key with their dominant hand as quickly and accurately as possible. each trial began with a fixation cross ( msec), fol- lowed by a -msec blank screen, a face stimulus ( , msec), and an interval of , msec until the beginning of the next trial, during which the participants were asked to blink if necessary. gender-to- key assignments were counterbalanced across participants. in the second part of the experiment, participants rated the por- traits for facial attractiveness on a -point scale, displayed hori- zontally below each portrait. the scale consisted of seven verbally labeled fields of equal size (very attractive, attractive, rather attrac- tive, neither–nor, rather nonattractive, nonattractive, and very non- attractive). the field corresponding to the estimated attractiveness value had to be clicked with the mouse. after the click, the cursor vanished and reappeared, together with the next portrait at a midline position. the participants were encouraged to utilize the whole scale for their ratings. the trial structure during the attractiveness rating was identical to that during the gender decision task, except for a longer face pre- sentation time ( , msec). each experimental part involved three blocks with randomized presentation of all portraits within each block. thus, each face was presented once per block and six times in all. at the beginning of each experimental part, the participants performed six practice trials with portraits not otherwise used in the study. the duration of the experiment was about min, including short breaks in the middle and at the end of each block. to ensure that participants were naive to the research question of the experi- ment, the gender decision block always preceded the attractiveness evaluation block, and facial attractiveness was not mentioned prior to the latter block. after the experiment, the participants were in- formed in detail about the aims of the study. electroencephalogram (eeg) data recording recordings were made from ag/agcl electrodes mounted in an electrode cap (easy-cap) at scalp positions (fp , fp , f , f , f , f , f , f , ft , ft , c , c , t , t , tp , tp , p , p , p , p , p , p , po , po , o , o , fpz, fz, cz, pz, oz, iz) accord- ing to the extended – system. the horizontal electrooculogram (eog) was recorded from the ft and ft electrodes, and the vertical eog was monitored from fp , fp , and two additional electrodes below each eye. the tp electrode was taken as the initial common reference, and afz served as the ground. impedances were kept below k . all signals were amplified using brainamp ampli- fiers and were recorded with a band-pass of . – hz, a -hz notch filter, and a sampling rate of hz. data analysis behavioral responses in the gender decision task were scored as correct if the appropriate key was pressed between and , msec after target onset. for the gender classification task, only correct classifications were considered, whereas all responses were accepted for the attractiveness rating task. mean reaction times (rts) were analyzed by repeated measures anovas involving the factors facial attractiveness and portrait gender. for the erp analysis, epochs of , msec were generated offline from the continuous eeg records, starting msec before stimulus onset. trials with artifacts, saccades, blinks, or incorrect behavioral responses (in the case of gender decisions) were discarded. erps were aligned to a -msec baseline. thereafter, they were averaged separately for each channel and experimental condition, low-pass filtered at hz, and recalculated to an average reference, excluding the two electrodes below the eyes. average erp waveforms for both gender decision and attractive- ness ratings were calculated separately. in a first step, three attrac- tiveness categories were defined for both tasks on the basis of the distributions across participants of the mean rating values of all facialacial attractivenessttractiveness but rather small effect of attractiveness for the -msec segment starting at msec [f( , )ff . , p . ]. however, all pairwise comparisons for this segment failed to reach significance (f(( sff . , p . ). the anova results for erps recorded during the at- tractiveness ratings (figure , right panel), involving the factors attractiveness (three levels) and electrode site, re- vealed significant effects of facial attractiveness in all time segments after msec (f(( sff . , ps . ; see table ). in the following, erp modulations prior to msec will be referred to as early effects because they were clearly located prior to the lpc time window, and they will be reported separately from later erp effects. early erp effects of attractiveness. the first signifi- cant effect of attractiveness, appearing between and msec, consisted of significant differences between nonattractive faces and faces of intermediate attractive- ness [f( , )ff . , p . ]. when gfp measures were analyzed within this time period, no significant effect of erp data the gfp measures of erps for the three-bin classifica- tion are depicted in figure . visual inspection shows that attractiveness had little effect during gender classifica- tion, but during attractiveness rating it increased gfp for attractive and nonattractive faces relative to the intermedi- ate ones. the following time segments of the erps were obtained from the transition times of gmd (figure , bottom panel): – , – , – , – , and – msec. mean erp amplitudes were calculated for these intervals. after msec, no clear segment borders were indicated by gmd. therefore, consecutive time peri- ods of -msec duration were selected for further analy- ses of the mean amplitudes between and msec. the same time segments were used for the idiosyncratic five-bin analysis. anovas of the erp segments involving the factors attractiveness and electrode site during the gender deci- sion (figure , left panel) revealed a single significant figure . global map dissimilarity (gmd) and global field power (gfp) of erps for the gender decision (top) and attractiveness rating (bottom) tasks. the vertical gray lines mark the segment borders, defined by gmd peaks. . . . g f p ( μv ) g m d gender decision attractiveness rating (msec) attractive nonattractive attractiveness rating gender decision intermediate sschachtchacht, w, werheid,, andand ssommerommer tive [f( , )ff . , p . ] and nonattractive [f( , )ff . , p . ] faces, whereas erps to attractive and nonat- tractive faces were indistinguishable [f( , )ff , p . ]. no signif icant interactions of attractiveness and segment appeared in these pairwise comparisons (fsff . , ps . ). in addition, we conducted an anova after normalizing with the vector method (mccarthy & wood, ) that did not reveal any significant difference be- tween the scalp distributions of both difference waves, nonattractive minus intermediate faces ( – msec), and attractive minus intermediate faces ( – msec) [f( , )ff . , p . ]. therefore, it appears that the early attractiveness effects were quite similar across at- tractiveness polarities and time segments. the following analyses probed into the nature of these early effects, es- pecially into whether they relate to the simultaneously ac- tive n component. to investigate whether the n component itself was influenced by attractiveness, we obtained peak amplitudes from the po electrode site in a latency time segment from to msec and submitted them to statistical analysis. whereas an anova revealed no effect of attrac- tiveness on peak amplitudes [f( , )ff . , p . ], peak latencies tended to be modulated by facial attractive- attractiveness appeared. in the subsequent time window, between and msec, pairwise comparisons revealed significant differences between attractive and intermedi- ate faces [f( , )ff . , p . ], whereas differences between nonattractive and intermediate faces appeared as a trend [f( , )ff . , p . ]. as depicted in fig- ure a, these early effects were characterized by positivi- ties at posterior electrodes and frontal negativities. as can be seen in figure a, the attractiveness effects during the first two segments ( – and – msec) showed similar topographies, with positivities at posterior electrodes and frontal negativities, although they emerged in different comparisons (nonattractive vs. intermediate and attractive vs. intermediate faces, respectively). there- fore, mean erp amplitudes in these two segments were compared directly in an anova involving the factors time segment, attractiveness, and electrode site. interest- ingly, this anova revealed significant main effects of segment [f( , )ff . , p . ] and attractiveness [f( , )ff . , p . ], but the interaction of both factors failed to reach significance [f( , )ff . ]. fur- thermore, when averaging erps across both segments, pairwise comparisons showed significant differences be- tween faces of intermediate attractiveness and both attrac- figure . grand mean erps to attractive, nonattractive, and intermediate faces at central and posterior electrode sites in both the gender decision (left) and attractiveness rating (right) tasks. μv – – msec fz – – cz – – – po – – – po – pz – o – o – oz μv – – msec fz – – cz – – – po – pz – – – po – o – o – oz attractive nonattractive neutral gender decision attractiveness rating table f values and significancef levels of anova results foroo erp mean amplitudes and global field power (gfp) during attractiveness classifications in selected time segments (in milliseconds), involving the factors facial attractiveness and—for mean amplitudes—electrode site – – – – – – – – – – mean amplitude . . . * . *** . * . ** . ** . *** . *** . *** gfp . . . * . *** . * . ** . ** . *** . *** . *** note—df , ; all p values are huynh–feldt corrected, where appropriate. *p . . **p . . ***p . . facialacial attractivenessttractiveness . , p . ]. visual inspection of the scalp distributions of the difference wave appears to indicate a similarity to the topography of the preceding p . however, profile analyses indicated that these topographies were also sig- nificantly different [f( , )ff . , p . ]. although these results indicate that the neural sources of early attractiveness effects are different from those of both the p and n components, the spatial and temporal distribution of this early attractiveness effect might be due to a combined and overlapping effect of attractiveness on a late part of the p and on the consecutive n com- ponent. in order to distinguish such modulations of the p and n from separate, attractiveness- dependent activity, we modeled equivalent dipoles of these com- ponents. such superimpositions should result from the accumulated activity of different neural sources—each generating one of the erp components when attractive ness [f( , )ff . , p . ], since they were slightly prolonged for both attractive and nonattractive faces rela- tive to the intermediate faces. figure b depicts the scalp distributions of the first vi- sual erp components—the p and the n —for all conditions of attractiveness, as well as the topography of the difference waves between attractive or nonattractive faces versus intermediate ones in the time segments in which these differences were significant. note that although the first effect of attractiveness covered the time range of the n , the scalp distribution of this effect appears rather different from the n topography. we verified this im- pression by an anova with normalized data, which re- vealed significant differences between the distribution of the n (taken from the intermediate condition) and the difference wave of nonattractive and attractive (averaged over both conditions) minus intermediate faces [f( , )ff figure . scalp distributions and dipole models of erps during attractiveness ratings. (a) early and late attractiveness ef-ff fects, depicted as topographies of difference waves between erps for attractive and nonattractive relative to intermediate faces. left side of panel: scalp distributions of the early attractiveness effect and equivalent dipoles for this effect. right side of panel: late effects of facial attractiveness. (b) scalp distributions of the p and the n components for the three attractiveness categories (left) and equivalent dipoles of these components (right) for the intermediate condition. note the dissimilarity of these topographies with those of the attractiveness effects above. a – msec – msec early effects of attractiveness dipoles – msec – msec late effects of attractiveness – msec nonattractive minus intermediate attractive minus intermediate – . μv μv . μv b attractive nonattractive intermediate dipoles n – msec p – msec – . μv μv . μv sschachtchacht, w, werheid,, andand ssommerommer mediate attractiveness categories (f(( sff . , ps . ). in contrast, neither the three intermediate (f(( sff . , ps . ) nor the two extreme attractiveness categories (f(( sff . , ps . ) were distinguishable from each other. both maps of difference waves—attractive versus intermediate and nonattractive versus intermediate faces—show a to- pography with a centroparietal positivity, which is typical for the lpc (see right panel of figure a). as described above, erps were also averaged itemwise for each portrait across the three presentations during the attractiveness rating and across the participants; that is, the erp for each of the portraits was based on re- sponses, disregarding unavoidable losses due to artifacts. for these erp wave shapes, average mean ampli- tudes at the pz electrode were calculated during the lpc segment between and msec. figure b shows a u-shaped relationship between the mean attractiveness rating values and lpc amplitudes at the pz electrode. this relationship was confirmed by a strong quadratic trend [f( )ff . , p . , r . ], whereas a linear and nonattractive faces are processed. therefore, in a first step, dipole models were obtained for the p and n components to faces of intermediate attractiveness (see figure b). for both components, principal component analysis (pca) indicated one component that explained more than % of the variance. for the p , a symmet- ric dipole pair was located in the middle occipital gyrus (talairach & tournoux [ ] coordinates: x mm, y mm, z mm; residual variance %). the neural sources for the n were located in the fusi- form gyrus (x(( mm, y mm, z mm; residual variance %). as indicated by the prof ile analysis above, distributions of the early effects of nonat- tractive and attractive faces were comparable. therefore, grand average difference waves for both nonattractive and attractive minus intermediate faces were used to derive neural source models. spatial pca of the – msec segment indicated two principal components explaining % of the variance in the data of the differences wave (pc explained . % and pc , . %). in a next step, we fixed the two dipole pairs from the p and the n in these difference wave data, which explained less than % of the variance. finally, we modeled the non/attractiveness effect with two single dipoles with a symmetry constraint. these dipole pairs explained % of the variance in the difference wave and were located in the fusiform gyrus (x mm, y mm, z mm) and the parahippocampal gyrus (x(( mm, y mm, z mm) (see figure a). late erp effects of attractiveness. pairwise post hoc comparisons for the three-bin analysis in the late time period between and msec (segments: – , – , and – msec) revealed significant dif-ff ferences only between attractive and intermediate faces (f(( sff . , ps . ). between and msec—but not in the preceding segment—attractive faces showed stron- ger gfp than did intermediate faces. between and msec, both attractive and nonat- tractive faces elicited different erps, as compared with faces of intermediate attractiveness (f(( sff . , ps . ), whereas attractive and nonattractive faces were indistin- guishable within these time segments (fs . , ps . ). as indicated by the anovas with gfp measures, these effects appear to be related to differences in ampli- tude (f(( sff . , ps . ). the following five-bin analysis was restricted to erps recorded during attractiveness ratings, since analysis on the basis of three-bin classifications revealed no signifi- cant effects in the gender decision task. also, the resolution for the five-bin analysis appeared too weak to reveal clear effects during early time segments. here, erps were aver- aged according to five attractiveness categories of about equal size, on the basis of the distribution of each partici- pant’s individual attractiveness ratings. mean amplitudes of gfp were assessed by a repeated measures anova, which revealed main effects of facial attractiveness in all time segments (f(( sff . , ps . ) starting at msec. as is shown in figure a, these effects resulted from en- hanced lpc amplitudes elicited by the most attractive and most nonattractive faces, as compared with all three inter- figure . late attractiveness effects at the pz electrode. (a) grand mean erps for the idiosyncratic five-bin analysis. (b) itemwise relationship between mean attractiveness rat- ings and lpc amplitudes at the pz electrode between and msec. – lp c a m p lit u d e ( μv ) (msec) a a m p lit u d e ( μv ) mean attractiveness rating b most attractive rather attractive intermediate rather nonattractive most nonattractive facialacial attractivenessttractiveness young, ). however, our data showed that n peak amplitudes were not affected by facial attractiveness (see eimer et al., ; schacht & sommer, ), and n slopes to attractive and nonattractive faces were only slightly delayed relative to those to intermediate faces. this prolongation is rather small in comparison with the sizeable and reliable increases of n latencies found in previous research, for example in response to inverted faces, which pose increased demands on holistic face per- ception (e.g., rossion et al., ; but see latinus & tay- lor, ). also, it is hard to see how increased demands on holistic face perception might account for the early attractiveness effect found in the present study. another assumption could be that such latency effects might re- flect differences in the duration of initial visual process- ing. this idea appears to be supported by the observation that the topography of the attractiveness effect showed a pattern somewhat similar to that of the p component. however, topographical comparisons indicated that the early attractiveness effect did not entirely match the p itself. furthermore, on the basis of our dipole models, we can rule out that this effect resulted from a superposition of p and n , since combining the dipole sources of these components was insufficient to account for the early attractiveness effect in the erp. instead, further dipole lo- calizations in this time interval, conducted without spatial constraints, yielded two dipole pairs that were located in the fusiform gyrus and the parahippocampal gyrus. within this network, the parahippocampal gyrus may act as a gate between extrastriate areas and emotion-related subcortical limbic structures, which may be involved in registering attractiveness but cannot be directly observed in erps. however, these findings suggest that the processing of attractiveness engages a network that is independent of those systems responsible for generating the p and n components. recently, vuilleumier and driver ( ) proposed that both attentional and emotional effects on visual percep- tion are due to top-down influences upon the visual cor- tex from brain regions farther upstream. although the upstream networks may differ, their effects on process- ing in peristriate cortex consist of similar activation pat- terns. both the time course and the dipole model of our early erp effects support this assumption of enhanced perceptual analysis of attractive and nonattractive faces in inferotemporal brain structures. in contrast with other emotional dimensions, there is no direct evidence for in- creased activation in peristriate or striate areas from im- aging studies. possibly such attractiveness effects have remained undetected because of a focus on such tasks as passive viewing (e.g., aharon et al., ) or gender judg- ment (e.g., o’doherty et al., ). the intriguing observation that erp modulations ap- peared to be comparable for both attractive and nonattrac- tive faces relative to intermediate ones also held for the later lpc effect. many previous studies have shown that lpc amplitude is related to the emotional content of a stimulus. this has also been true for previous studies that directly investigated attractiveness and found larger lpc amplitudes between and msec for attractive than trend was significant but much smaller [f( )ff . , p . , r . ]. in order to account for any contribu- tions of emotional expression to the relationship between attractiveness and lpc amplitude, we calculated the re- gressions after partialing out emotional expression from attractiveness. the u-shaped relationship between attrac- tiveness and lpc amplitude increased slightly [f( )ff . , p . , r . ] after taking into account emo- tional expression, but the linear trend dropped to nonsig- nificance [f( )ff . , p . , r . ]. discussion the present experiment assessed whether and when facial attractiveness—subjectively appraised by the observer—would affect the processing of faces, as re- flected by scalp-recorded brain potentials. in addition, we were interested in whether attractiveness appraisal would depend on the task performed on the face. as main re- sults, two qualitatively different effects of attractiveness appeared in the erps, an early effect around msec and a later one starting around msec. interestingly, although both erp effects clearly differed in latency, they shared two important features: first, both appeared when facial attractiveness was task relevant but were mostly ab- sent when the faces were categorized for gender. second, these effects appeared similarly for both attractive and nonattractive faces, as compared with intermediate faces. a main result of the present study is the observation of an early effect of facial attractiveness starting around msec. this finding confirms several previous reports indicating that facial attractiveness might be processed rapidly. for instance, olson and marshuetz ( ) found that even very little information may be sufficient for at- tractiveness appraisal, but their behavioral study provided only limited evidence about the temporal localization of the effect. further supporting evidence comes from stud- ies reporting early erp effects for emotional dimensions other than attractiveness (e.g., pizzagalli et al., ). ex- tending these previous findings, the present study showed that the attractiveness dimension can have differential ef- fects on brain activity at least as early as other emotional or affective stimulus dimensions, such as emotional facial expressions (schupp, Öhman, et al., ; schutter et al., ), emotional connotations of written words (kissler, herbert, peyk, & junghöfer, ), or affective content of pictures (schupp et al., a, b). in this respect, our findings are in line with our earlier study revealing an erp effect around msec poststimulus (werheid et al., ), notwithstanding the differences in timing and scalp distributions of the early attractiveness effects in both ex- periments, which may have been due to differences in the variability and number of the faces employed or in task demands (attractiveness rating vs. binary classification). interestingly, the early erp modulation covered the time range of the n , a component that has been re- lated to configural processing of facial features and ho- listic face perception (see, e.g., bentin & deouell, ; schweinberger, pickering, jentzsch, burton, & kauf-ff mann, ) and to structural encoding of faces (bruce & sschachtchacht, w, werheid,, andand ssommerommer stimuli’s increased motivational significance and arousal value (e.g., kayser et al., ; schupp et al., ). en- hanced p amplitudes for nonemotional stimuli were found when the erp-eliciting stimulus was attended (e.g., johnson, ), infrequent, or task relevant (e.g., picton & hillyard, ). thus, the p is considered to be an erp component elicited by active cognitive analysis of relevant stimuli (see bashore & van der molen, , for a review). in the case of emotional stimuli, enhanced p / lpc amplitudes have been suggested to reflect increased continued analysis initiated by the increased intrinsic rel- evance of emotional stimuli (lang, bradley, & cuthbert, ). we therefore suggest that the augmented lpc amplitudes to attractive as well as to nonattractive faces found here reflect their enhanced elaborative analysis as compared with intermediate faces—resulting from aug- mented perceptual analysis, as possibly reflected in the early erp effect described above. further clues for the interpretation of our attractive- ness effects in erps come from results regarding the in- fluence of the task factor, which was used to investigate whether attractiveness is appraised in an automatic and task- independent fashion. during gender decision, both the early and late erp modulations were absent or— considering the small effect in one of the lpc intervals— at least very much reduced. thus, both the early and late attractiveness modulations of our erps were highly sus- ceptible to task factors. this is in contrast to early reports with affective pictures, which have shown both early erp and lpc modulations, even when a cognitive attention task was performed concurrently to viewing the pictures (schupp et al., b). however, our results are in line with other studies that have shown that emotion effects in the lpc are modulated by task demands (diedrich, naumann, maier, becker, & bartussek, ; eimer et al., ; hajcak, moser, & simons, ; schupp et al., ). schupp et al. ( a) suggested that the emotion- dependent erp modulations with affective pictures re- sult from reflective visual attention facilitating sensory encoding, as reflected by early erp components, which in turn cause enhanced continued processing (an lpc). the researchers considered these effects of affect to be analo- gous to those of orienting attention toward a specific loca- tion in space (mangun, jha, hopfinger, & handy, ). for the present case of attractiveness, such reflexive atten- tion allocation does not seem to hold. moreover, the ap- praisal of attractiveness does not appear to be a mandatory process, invoked whenever a face is perceived. instead, attractiveness appraisal seems to require voluntary atten- tion to the attractiveness dimension and may compete with other resource-drawing processes, even when the face as such is the focus of attention, as is the case during gender decisions. this is in line with findings from studies on similar judgments in other domains. recently, höfel and jacobsen ( ) showed lpc effects to graphic patterns to be restricted to explicit aesthetic categorization; the lpc effect did not appear spontaneously when no overt response was required. similar to schupp et al.’s ( a) account of emotion effects on erps, we propose that the present erp findings for less attractive faces (johnston & oliver-rodríguez, ; oliver-rodríguez et al., ; werheid et al., ). two observations from the present study are at variance with these previous reports. first, lpc modulations, con- sisting of enhanced amplitudes to attractive relative to in- termediate faces, started about msec earlier than in the studies mentioned above. second, in later time segments, the relationship between attractiveness ratings and lpc amplitudes was not monotonic or even linear, since the linear trend was small and vanished when the moderate relationship between the valence of facial expression and attractiveness was taken into account. this u-shaped re- lationship between attractiveness and erp amplitude was especially clear in the idiosyncratic five-bin and itemwise analyses, which mainly showed differences between the intermediately attractive faces and the positive and nega- tive extremes, respectively, but none between the extreme attractiveness categories after around msec. a possible explanation for the discrepancies between the present and previous findings is related to stimulus characteristics and task requirements. whereas the present study used high-quality color photographs, the studies of johnston and coworkers (johnston & oliver-rodríguez, ; oliver-rodríguez et al., ) employed schematic line drawings with electronically manipulated proportions. furthermore, in comparison with our previous study (wer- heid et al., ), the present study used a wider range of stimuli with regard to facial attractiveness, indicated by comparing the attractiveness ratings of both experiments. further differences between the present and previous stud- ies concern the task demands. in the studies of johnston and coworkers, no task had to be performed on facial stim- uli while erps were recorded. in our own previous study, dichotomous decisions between attractive and nonattrac- tive faces had to be made. obviously, the direct evaluation of attractiveness on a scale ranging from very nonattractive to intermediate to very attractive faces establishes an inter- nal continuum with two clearly defined poles, as well as a reference point that it has been suggested is derived from continuous updating of stimulus representations (helson, ). the finding that emotion-related lpc effects are affected by response mode should be considered in further erp research. several studies have shown the p to re- flect, besides emotional dimensions, the distance between a current stimulus (mostly numerical or a symbol) and a reference point derived from an internal model about rel- evant stimuli (see, e.g., ullsperger & grune, ). the clear u-shaped relationship between attractiveness ratings and lpc amplitudes might therefore arise from the maxi- mal distance of very non/attractive faces from the refer- ence point—derived from intermediate faces. notably, however, the present findings are in line with previous research reporting lpc modulations in response to affective pictures. several studies have shown that both pleasant and unpleasant pictures elicit an enlarged lpc as compared with neutral pictures (e.g., cuthbert et al., ; schupp et al., ; schupp, junghöfer, et al., ). since the effect of positive emotional valence is similar, albeit somewhat smaller, than that for negative valence, this effect has been attributed to the emotional facialacial attractivenessttractiveness when faces have to be processed for other attributes. thus, they may reflect the voluntary aesthetic appraisal of faces rather than bottom-up attention processes driven by sexual attractiveness. author nor te we thank mareike bayer, maria gruno, and roland nigbur for as- sisting in data collection, and rainer kniesche and thomas pinkpank for technical support. this research was supported by the german re- search foundation through grant so / - to w.s. correspondence concerning this article should be addressed to a. schacht, department of psychology, humboldt university at berlin, rudower chaussee , d- berlin, germany (e-mail: schachta@hu-berlin.de). note—this article was accepted by the previous editorial team, when john jonides was editor. refererr nces aharon, i., etcoff, n., ariely, d., chabris, c. f., o’connor, e., & breiter, h. c. 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( ). the amplitude of the p component of the event-related potential: review and synthesis. in p. k. ackles, j. r. jennings, & m. g. h. coles (eds.), advances in psychophysiology (vol. , pp. - ). greenwich, ct: jai press. can be explained by the allocation of attention to attractive and nonattractive faces, resulting in enhanced elaborative processing. however, in facial attractiveness, the allocation of attention does not seem to be mandatory, because the ef-ff fects were absent in the gender classification task—that is, when attention was allocated to task-relevant dimensions other than attractiveness. obviously, the internal continuum or reference point (see ullsperger & grune, ) of facial attractiveness—as far as it is reflected in erp measures—is not derived automatically when the task requires decisions about faces that are unrelated to attractiveness. the task dependency of the facial attractiveness effects in erps argues against an underlying mechanism tied in a reflexive, bottom-up fashion to sexual attraction or re- productive fitness. the same argument could be based on the similarity of the effects for attractive and nonattrac- tive faces. why should a mate-detecting system respond in the same way to both extreme values on the attractive- ness scale? when discussing the task dependency of our attractive- ness effects, one must take into account that the sequence of tasks was not counterbalanced, since the gender deci- sion always started the experimental session and was fol- lowed by the attractiveness rating task, in order to prevent attention allocation to attractiveness during gender deci- sions. therefore, we cannot rule out that the internal con- tinuum of facial attractiveness might be established over time—that is, with each repetition of the facial stimuli. nevertheless, in our opinion the task sequence in the pres- ent experiment cannot explain the absence of attractive- ness effects during gender decisions; if attractiveness were processed automatically and task-independently, it should have affected face processing from the beginning. finally, we would add a word of caution as to the speci- ficity of the present findings for facial attractiveness. onl a priori grounds, the task specificity of the present find- ings argues for a domain-general effect. that is, findings similar to the present ones might be obtained whenever aesthetic or other judgments are required on sets of stimuli that vary in a continuous fashion on one or several di- mensions. from an empirical perspective, such domain generality is supported by the facts that the localization of the early effects was not tied to a presumably face-specific component, such as the n , and further that similar ef- fects have been observed for aesthetic judgments of non- face objects (höfel & jacobsen, ). nevertheless, the present effects seem to hold for facial attractiveness, and their generalizability to other objects or dimensions has to await further scrutiny. in conclusion, facial attractiveness can modulate brain processes as early as msec after a face is encountered. the early effects appear to take place in a network that is independent of those responsible for visual and struc- tural analysis (the p and n components) and is followed by the modulation of the lpc, possibly indicat- ing enhanced continued processing. both early and late effects are similarly prominent for attractive and nonat- tractive faces relative to intermediate ones. in contrast to f indings from other emotional domains, the effects of attractiveness are strongly task dependent and vanish sschachtchacht, w, werheid,, andand ssommerommer crommelinck, m., & guérit, j.-m. 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( ). averageness, exaggeration, and facial attractiveness. psychological science, , - . rossion, b., delvenne, j.-f., debatisse, d., goffaux, v., bruyer, r., << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages false /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /leavecolorunchanged /dothumbnails false /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize true /opm /parsedsccomments true /parsedsccommentsfordocinfo true 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/hwresolution [ ] /pagesize [ . . ] >> setpagedevice journal of black studies xx(x) – © the author(s) reprints and permission: http://www. sagepub.com/journalspermissions.nav doi: . / http://jbs.sagepub.com jbsxxx . / jenkinsjournal of black studies © the author(s) reprints and permission: http://www. sagepub.com/journalspermissions.nav george mason university, fairfax, va, usa corresponding author: toby s. jenkins, george mason university, university dr., ms b , fairfax, va email: tjenkin @gmu.edu a beautiful mind: black male intellectual identity and hip-hop culture toby s. jenkins abstract in a field like hip-hop, where written and verbal communication are the two primary forms of work production, the mind or intellect of the artist should be viewed as the very thing responsible for success. however, unlike other writing-intense fields, the mind of hip-hop artists is often the least valued and least lauded trait. hip-hop artists, whether they realize it or not, have more to offer. they are more than the things that they possess. they are writers. they are thinkers. this article examines intellectualism in hip-hop music—its presence, shortcomings, and ultimate value. keywords hip-hop and academics, knowledge production, intellectuals adjusting to the neighborhood: hip-hop’s place in american popular culture seven years ago, john mcwhorter ( ) wrote an article in the city journal titled “how hip-hop holds blacks back.” after recently reading his piece, i immediately wondered how the author feels today, at a time when even hip-hop article journal of black studies xx(x) artists are saying that mainstream music is less than impressive (carter, ; jones, ). hip-hop has never been perfect. but it is not all worthless. in his article, mcwhorter outlines the various ways in which the lyrics of hip-hop music are poor influences on black youth. he identifies grandmaster flash’s classic “the message” as the critical changing point where hip-hop evolved from fun party music to destructive and nihilistic street anthems. his analysis is a result of a literal rather than critical read of the song: grandmaster flash’s ominous hit, “the message,” with its cho- rus, ‘its like a jungle sometimes it makes me wonder how i keep from going under,” marked the change in sensibility. it depicted ghetto life as profoundly desolate. . . . music critics fell over themselves to praise “the message,” treating it as the poetry of the streets—as the elite media has characterized hip-hop ever since. the song’s grim fatalism struck a chord; twice, i’ve heard blacks in audiences for talks on race cite the chorus to underscore a point about black victimhood. so did the warning it carried: “don’t push me, ’cause i’m close to the edge,” menacingly raps melle mel. the ultimate message of “the message”— that ghetto life is so hopeless that an explosion of violence is both justified and imminent—would become a hip-hop mantra in the years ahead. (mcwhorter, ) there is a strong difference between the “message” and insight that this song provided into the lived realities of urban poverty and the post- s “script” that followed the initial emergence of gangsta rap, where all artists (regard- less of how truthful) had to be gangstas, pimps, thugs, or millionaires (kitwana, ; watkins, ). when street-level politics of struggle and survival first began to surface in rap music, there was authenticity in the lyrics—even in the very first gangsta rap that came out of southern california. in many ways, the writing of hip-hop artists like grandmaster flash and melle mel demonstrated the ethic that drives critical race theory: the importance of allowing the margin- alized to speak and for their voice to be raw, real, and authentic (barnes, ). barnes ( ) explains the importance of this theory: minority perspectives make explicit the need for fundamental change in the ways we think and construct knowledge. exposing how minority cultural viewpoints differ from white cultural viewpoints requires a delineation of the complex set of social interactions through which minority consciousness has developed. distinguishing the conscious- ness of racial minorities requires acknowledgement of the feelings and jenkins intangible modes of perception unique to those who have historically been socially, structurally, and intellectually marginalized in the united states. (p. ). a critical component of acknowledging such modes of perception includes hearing real stories of the cultural experience. almost a decade later, the worth of hip-hop warrants revisiting. undeniably, there are basic aspects of hip-hop music that have improved since both its inception and the publication of mcwhorter’s ( ) article. the musical production of today is more complex than some of the mixed beats that provided the backdrop to rhymes in the late s. in the early days of hip-hop, the music was simply a back- drop, and the dj’s artistic ability was demonstrated by mixing existing songs with new dance beats while creating a “break” so the dancers could take action. dancers and emcees were the central players in early hip-hop. music producers have now come into play in a much more active and recognized way. contemporary producers have indeed elevated the music. additionally, the business acumen of hip-hop artists has also changed. artists are now leveraging their roles in the entertainment industry, and some are individu- ally enjoying a payday that no other music entertainers of color have ever seen in any genre of music. and lyrically, the style of rap has also been enhanced. after decades as an art form, competition has made emcees strive to perfect their rhythm, cadence, and style. however, there are two compo- nents of lyrical analysis: lyrical content (what they are saying) and lyrical style (how they say it). although it may be difficult to argue that lyrical con- tent is getting better with age, to say that “hip-hop creates nothing” is wrong (mcwhorter, ). at its best, hip-hop creates writers and thinkers in young people of color—something many schools have failed to do (gause, ; harper, ; jenkins, b; noguera, ). the invisible man speech is my hammer, bang the world into shape. (mos def, [smith], a) in a field like hip-hop, where written and verbal communication are the two primary forms of work production, the mind or intellect of the artist should be viewed as the very thing responsible for success. however, unlike other writing-intense fields, the intellect of the hip-hop artist is often the least valued and least lauded trait. whether it is in the lyrics of songs or in the media depictions of the artist, for male hip-hop artists, the possession of journal of black studies xx(x) power (business ownership), prowess (beautiful women), and paper (money) are consistently viewed as the character traits that earn bragging rights. shows like mtv cribs ( ), the flavor of love ( ), and i want to work for diddy ( ) have illustrated that the trend to confine the life worth of the male rapper to cribs, relationships, and business ventures has become the industry standard. but hip-hop artists, whether they realize it or not, have more to offer. they are more than the things that they possess. they are writ- ers. they are thinkers. at its core, hip-hop culture has always acknowledged intelligence. five basic elements have been identified as the core contextual framework of hip-hop culture: the b-boy/b-girl (dance or break dance), the emcee (voice), the dj (music), graffiti (art), and knowledge (the consciousness) (watkins, ). many elements have found their own independent acceptance and growth. such has been the case with break dance. with nationally syndicated television shows and competitions, a new life and energy has been breathed into the art of break dance. in many ways, hip-hop as a broad culture has moved from the separate corners and blocks of the urban street community and taken up new residences within the larger popular culture. it now belongs to everyone. but not all elements have faired so well in the move. it seems that when it comes to being fully valued and welcomed into the new, wider community of popu- lar culture, some elements were broken in the move. this is what happened to knowledge. knowledge and intelligence within hip-hop does not seem to have a place within american pop culture. when we talk hip-hop in the larger society, there is often no mention of an artist being smart, intelligent, or brilliant. this lack of appreciation for the intellect of the writer often is not present in other fields. how many male book authors are praised for the look of the woman on his arm rather than the intellectual or creative value of the books that he has produced? the ways in which the mind of the hip-hop artist is all but ignored within popular culture is, largely, a part of a broader trend within american society to disregard the experiences, perspectives, and ways of being, knowing, and expressing that are offered forth by african american men. so, in the same way that african american male minds have been underserved in classrooms, channeled into prisons, and in some cases, all but ignored within american society, the mind of the hip-hop artist is also devalued within the subordinate popular culture (jenkins, b). written over years ago, ralph ellison’s ( ) classic text invisible man symbolically shines a light on the lack of inclusion of black men in broader society. ellison’s america was a place in which a man becomes invisible because society refuses to see him as anything more than a stereotype. jenkins now a century later, in contemporary society, there is only an illusion of inclu- sion. the real identity of many black people (as strong, culturally grounded, and intelligent) still remains invisible. this is a society in which even our president is criticized for being too smart (professorial) and walks a thin line of being seen as too ethnic (poor, ; rappaport, ). if the man holding one of the most critical positions in our society must succumb to a manufac- tured and socially palpable identity, what role could artists possibly occupy as strong and vocal intellectuals? why is it so difficult for black men to be their full and authentic selves in the united states? persisting white supremacist and patriarchal thinking as well as a patriot “gang” culture definitely play a part. hooks ( ) provides an explanation of the influence of white supremacy: nowadays in the imperialist white-supremacist patriarch culture, most boys from poor and underprivileged classes are socialized via mass media and class-biased education to believe that all that is required of their survival is the ability to do physical labor. black boys . . . have been socialized to believe that strength and stamina are all that really matter. groomed to remain permanent members of an underclass, groomed to be without choice and therefore ready to kill for the state in wars whenever needed, back males without class privilege have always been targets for miseducation . . . the curiosity that may be deemed a sign of genius in a white male child is viewed as trouble making when expressed by black boys. (p. ) within hip-hop, it is not so much that those thoughtful and socially aware artists who dare to resist the stereotype are not recognized as being positive. most agree that these artists are positive. in fact, positivity has almost become a badge of dishonor—a marker that means you may have a lot of skill but you probably do not move a lot of product. so though it is nice to be positive, it is not necessarily lucrative. but agreeing on whether or not these artists are posi- tive or liberating writers is not the issue. the problem is rather that critical thought and critical citizenship have never been traits that society has preferred to see demonstrated by black men (hooks, ; jenkins, ). racism can only thrive in environments that believe the stereotype. so, the mass culture is literally not buying the persona of the intelligent, socially aware, and politically critical black man. in music, we want our thugs, and in the white house, we do not want anyone that makes us feel dumb. and beyond the turbulent relationship between black men and america, the society broadly has limited tolerance for any divergent voice (regardless journal of black studies xx(x) of color). american patriotism is often approached through a very narrow and one-dimensional lens (jenkins, ). like any gang culture, to be a full member (citizen or patriot), you must uncritically accept and support the organization. those who voice opposition often face a verbal beating and the label of outcast. like any strong gang, you either get down with us or get beat down by us. negative talk and thought about the country is not allowed. and so, the need to challenge the idea of who gets to define patriotism and whose voice is allowed to be both heard and valued is a real issue. more public critiques are needed of the traditional conceptualization of “genius” as being western, white, and male and of “patriotism” as being synonymous with conformity and blind allegiance. in contemporary public blogs, these outdated ideologies still persist. a blog post sharing the “top geniuses of all time” listed white men from the western world (http:// mind life.com/blog/ / / /list-of-geniuses-top- -influential- minds/). new ways to define and appreciate genius and intellectual contribu- tions must be developed. clearly, people of color, women, radical activists, and many political prisoners have transformed our society for the better in deep and meaningful ways. they have pushed to expand our laws, our behav- ior, and our thinking. the breakdown i’ve got an appetite for destruction—but i scrape the plate. (jay-z, [carter], )) the impact of the largely stereotypical images of hip-hop artists that are advanced through popular culture and the media is both deep and important to discuss. popular culture has always played an important role in shaping public opinion. the basic premise of mcwhorter’s ( ) argument regard- ing the strong influence of entertainment does have merit. in the s, mov- ies, commercials, and newspaper articles were used to sway public opinion against the use of marijuana and eventually led to its outlaw in (bonnie & whitebread, ; lupien, ; parry, ). many of the negative ste- reotypes about single black mothers (that still hold sway) were generated in the s during the media frenzy in which images were widely published of mostly black crack mothers, crack babies, and welfare recipients (cox, ). these depictions helped to push forward extremely unforgiving and what we now know to be racially unbalanced drug laws. and you can look at any decade to see that during times of war, nothing drums up broad public support for military engagement better than a swarm of war-based movies jenkins (carver, ). when it comes to seducing the public’s opinion, pop culture has been around the block. but it is probably more powerful now than ever before. this is partly due to the increase in venues for mass media consump- tion (music tv, expanded and digital cable, satellite radio, ipods, cell phones with video and music downloads, hip-hop artists as fashion and restaurant moguls, etc.) (hooks, ). we can now access media - in our homes, in our cars, or while simply walking down the street. we no longer have to walk into the living room or run to the newsstand for the daily news. we simply carry it in our purse, and it is available at the click of the browser button. and so, popular culture continues to influence the public but now with a much wider reach. the one thing that holds constant is the fact that negative and false propaganda is still as much of an issue now as it was in the s. and stereotypes are still broadly projected about many communities. arguments have been had for decades about who should take the weight for the negative impact of hip-hop music. some argue that artists bear respon- sibility for the work that they produce. artists have blamed parents by saying that parents should monitor their child’s consumption of music. but many young people simply do not have good parents. what about the children of drug-addicted parents? other kids have parents who are struggling to parent in the midst of hard life circumstances. this is often the case for kids who have single parents working multiple jobs just to afford food and shelter. in either case, parents may barely see their children, much less be able to ade- quately monitor what they watch or hear. whatever the reason, the question is, do we allow these children to fall prey to bad influence simply because of circumstances of birth? and beyond children, as mentioned previously, media has psychological influence on adults as well. this is why advertising is such a major industry. so when it comes to hip-hop, what do our teachers, classmates, neighbors, and citizens both within and outside of the united states often see when con- suming the popularized hip-hop product? the five core elements of hip-hop can be replaced by the five core stereotypes of the black male hip-hop artist: the nihilistic, self-centered, caked-out mogul with a god complex; the unedu- cated, lazy, absentee father; the imprisoned and angry criminal; the cool pimp; and the ignorant thug. according to bell hooks ( ), internalized self-hatred is more pronounced now then in the era of segregation. hooks goes on to discuss the critical differences between a time period when african americans were demeaned, stereotyped, and caricatured by a larger society that openly admitted to hate versus a current era, where white-supremacist, patriarchal thinking is cleverly hidden behind curtains of verbal democracy and inclusion. journal of black studies xx(x) when we watched shows like tarzan or amos ‘n’ andy that we enjoyed, we were ever aware that the images of blackness we saw on these programs were created by folks who, as mama would say, “did not like us.” consequently, these images had to be viewed with a critical eye. in my own family this critical vigilance began to change as the fruits of the civil rights struggle became more apparent. mama’s last child would watch television alone with no adult voices teaching her a resist- ing gaze. . . . once laws desegregated the country, new strategies had to be developed to keep black folks from equality, to keep black folks in their place. while emerging as less racist than it had once been, televi- sion became the new vehicle for racist propaganda. black people could be represented in negative ways, but those who had wanted there to be jobs for black actors could be appeased. nothing pushed a white suprema- cist aesthetic more than television, a medium where even dark-haired white women had to become blondes in order to succeed. (hooks, , p. ) though written primarily about television, hooks’ comments can be broadly applied to mass media, as the industry is now more blended and less segmented as in the past. music is no longer relegated to radio—it is a television-, radio-, and internet-based form of entertainment. and it is not simply an issue of its broad reach. the cultural implications of the negative stereotyping in popular culture are even more disheartening. today, some of these images are being put out by black folks whom consumers want to love and trust. today, it is less a matter of “they hate us” and more a capitalistic issue of “they don’t care about anything but money.” and today, given the massive availability of media, it is much harder to disregard and resist. this is what hooks meant. in a capitalistic society, a culture where mass media largely sets the agenda, it is difficult to argue that there is no media influence on consumers’ concept of both themselves and others. especially when it comes to hip-hop culture. hip-hop culture extends beyond music and dance. it breaks down the sep- aration of pop culture and daily life so that pop culture is not merely a form of entertainment but a lifestyle (bynoe, ; kitwana, ). the genera- tions that identify with hip-hop embody the culture (sometimes good and bad) in all of who they are, bringing the culture into the way they interact, dress, think, and establish life priorities and goals (bynoe, ; kitwana, ). one problematic example was the case of the “thug.” in the early s, it was the embraced stereotype of the day. conversations were had about it, articles were written about it, bloggers blogged about it, and of course, popular songs spoke on it (“why black american chicks,” ). and in jenkins , almost serving as an affirmation of society’s embrace of the thug image, destiny’s child wrote a song glorifying it called “soldier.” in the song, the group made statements like “if your status ain’t hood, i ain’t checkin’ for him. better be street if he lookin’ at me.” they went on to state, “we like dem boys up top from the bk [brooklyn]. know how to flip that money three ways. so quick to snatch up your beyonce” (knowles, rowland, williams, & harrison, ). in my gloss magazine article, i offer the following explanation of the thug phenomenon: undoubtedly, most women, at that time, were not actually seeking a thug or gangsta. if we take time to dissect and define these two simple personas in their most literal sense we are talking about a man that is disrespectful (thug) or a man that is criminal (gangster), and with both a man that lacks the ability to build familial, friend or kinship connec- tions (hood). it is important that we understand a “hood” is a place where people do not enact the role of neighbor—where creating a sense of kinship and being a neighbor is absent from the experience. so, a hood can be created within an urban ghetto as well as in an afflu- ent suburb where people don’t speak to or look out for one another. if you were raised in a government housing project but had neighbors that looked out for you—then you were a part of a neighborhood, how- ever poor it might have been. and if you are loving a man that is loving you back, and also loving his mother, father, nieces, nephews, friends, and also looking out for the young brothers on the block, however poor he might be, his status is not “hood.” of course, these terms are not meant literally, they are meant to represent something else. but it may be more socially beneficial to stop using them and to begin using the language that reflects what we love about black men. our love of the “bad boy” is not new. it is as old as our love for men that dared to stand up and to challenge the status quo, to go against the grain as did our beloved malcom x or nat turner. we actually don’t love badness. we love strength that is sometimes inter- preted as being bad. women were saying they wanted a thug—but what they wanted was a strong man. what women were seeking was not a gangsta, but rather, a man that was confident and that commanded respect from those around him. (jenkins, a) with all of the various ways that we can describe, label, and identify black men, why are there only a few, limited, and stereotypical identities present in popular culture? journal of black studies xx(x) beyond the stereotype: hip-hop artists as knowledge producers i used to speak the king’s english, but caught a rash on my lips. (mos def, [smith], a) although many hip-hop artists may share former identities as thugs and gangsters, these are not their only identities. the failure to acknowledge truly talented hip-hop artists as intelligent demeans both the art production and the artist. hip-hop artists are indeed talented, but they are not just talented. and though hip-hop artists may exhibit strength (as evidenced by their ability to navigate their way through poverty, crime, and oppression in america), they are not just strong. when artists write their own lyrics and those lyrics are bril- liant examples of critical thought, social critique, or creative writing, they are exhibiting more than talent and strength. they are showcasing intelligence. in their recent book, born to use mics: reading nas’s illmatic, michael eric dyson and sohail daulatzai ( ) acknowledge the depth and critical meaning often found in the lyrics written by rappers. because the african american community has a history of valuing community-based knowledge— of understanding that knowledge is produced in our homes, on our streets, and through our cultural production—it is important that the black community continue to challenge the notion of who is allowed to be considered knowl- edge producers and what venues (beyond educational institutions) are allowed to be viewed as points of knowledge production (hill collins, ). when it is at its best, the lyrics penned by hip-hop artists are a valuable form of nontraditional knowledge and social critique of the american experi- ence. i often use lyrical analysis of various forms of music, hip-hop in par- ticular, in my classrooms in order to encourage students to wrestle with the counter experience of people of color. the work of many hip-hop artists equals ellison’s ( ) classical work in social value and meaning. in table , i share brief lyrics (with notes) of four black male hip-hop artists in order to demonstrate this value. jay-z is a perfect example of an artist who has not been recognized enough for his intelligence. within the culture he is seen as successful, powerful, rich, and smart. but the smart piece has not always been widely translated outside of the culture. on a recent appearance on the oprah winfrey show, the video introduction of jay-z still focused on the traditional ways in which manhood and success have been defined in america: money, power, ownership, and beautiful women (hurt, ). however, the larger article written about jay-z in o magazine took a different perspective, with oprah interviewing him and jenkins table . lyrics notes “i want to talk to you,” nas (jones, ) i wanna talk to the mayor, the governor, the . . . president i wanna talk to the fbi, and the cia, and the . . . congressman . . . i’m just a black man why y’all made it so hard, damn . . . gotta go create his own job mr. mayor imagine if this was your backyard, mr. governor imagine if it was your kids that starved imagine your kids gotta sling crack to survive, swing a mack to be live, cart ack to get high . . . mr. president, i assume it was negligence, your streets are upside down and i’m here to represent the need for poor communities to have voice and to be heard by the american power structure black male unemployment lack of political empathy and understanding of the life of the oppressed drug-related crime street violence the role of the hip-hop artist to loudly speak the truth and serve as a “street” representative for those being ignored by society “changes,” tupac shakur ( ) i see no changes wake up in the morning and i ask myself is life worth living should i blast myself? i’m tired of bein’ poor and even worse i’m black my stomach hurts so i’m lookin’ for a purse to snatch cops give a damn about a negro pull the trigger kill a n* he’s a hero give crack to the kids who the hell cares one less mouth on the welfare first ship ’em dope and let ’em deal to brothers give ’em guns step back watch ’em kill each other it’s time to fight back that’s what huey said shots in the dark now huey’s dead nihilism in the black community poverty and racism socioeconomics that lead to crime racial police brutality lack of social concern for poor communities government corruption black-on-black crime silencing of black activists need for unity need for community love need for concrete and holistic strategies and efforts toward change (continued) journal of black studies xx(x) table . (continued) (continued) lyrics notes i got love for my brother but we can never go nowhere unless we share with each other we gotta start makin’ changes learn to see me as a brother instead of distant strangers and that’s how it’s supposed to be how can the devil take a brother if he’s close to me? i’d love to go back to when we played as kids but things changed, and that’s the way it is we gotta make a change . . . it’s time for us as a people to start makin’ some changes. let’s change the way we eat, let’s change the way we live and let’s change the way we treat each other. you see the old way wasn’t working so it’s on us to do what we gotta do, to survive. “mathematics,” mos def (smith, ) the song’s title is a play on words. it articulates the charge of the emcee to sum up life. additionally, he creatively uses numbers throughout the song to further complicate the lyrics working class poor better keep your alarm set streets too loud to ever hear freedom ring say it backwards in your sleep, “it’s dangerous to dream” it’s a number game, but shit don’t add up somehow like i got, sixteen to thirty-two bars to rock it but only % of profits, ever see my pockets like sixty-nine billion in the last twenty years the daily realities of poverty-line living that causes you to always be on call, always be on guard, always be attached to a -to- reality rather than a life of hopes, dreams, and optimism the ways in which artists are not equal partners in the entertainment industry misdirected government priorities drug-trafficking laws and the criminal justice system drugs and health jenkins table . (continued) (continued) lyrics notes spent on national defense but folks still live in fear . . . like sixteen ounces to a pound, twenty more to a ki a five minute sentence hearing and you no longer free . . . like nearly half of america’s largest cities is one-quarter black that’s why they gave ricky ross all the crack crack mothers, crack babies and aids patients young bloods can’t spell but they could rock you in playstation . . . like % of americans own a cell phone so they can hear, everything that you say when you ain’t home i guess, michael jackson was right, “you are not alone” you wanna know how to rhyme you better learn how to add it’s mathematics . . . yo, it’s one universal law but two sides to every story three strikes and you be in for life, mandatory when the average minimum wage is $ . you best believe you gotta find a new grind to get cream the white unemployment rate, is nearly more than triple for black so frontliners got they gun in your back bubblin crack, jewel theft and robbery to combat poverty and end up in the global jail economy stiffer stipulations attached to each sentence budget cutbacks but increased police presence lack of education and misdirected priorities tracking and tapping capabilities now present with mass mobile phone usage an emcee’s job is to sum up life strict sentencing laws and the criminal justice system poverty unemployment and violence poverty and prison multiple ways that millions of peoples’ lives are not their own the various ways that society treats its citizens as numbers; a lack of a humane experience in the end, those on top need to be concerned about all of those below because when the oppressed reach their breaking point, everyone will feel it; there is power in numbers journal of black studies xx(x) table . (continued) lyrics notes and even if you get out of prison still livin join the other five million under state supervision this is business, no faces just lines and statistics from your phone, your zip code, to your s-s-i digits the system break man child and women into figures two columns for who is, and who ain’t n* numbers is hardly real and they never have feelings but you push too hard, even numbers got limits why did one straw break the camel’s back? here’s the secret: the million other straws underneath it—it’s all mathematics “american dreamin’,” jay-z (carter, ) this is the shit you dream about with the homie steamin’ out back-back-backing them beamer’s out seems as our plans to get a grant then go off to college, didn’t pan or even out we need it now, we need a town we need a place to pitch a tent, we need a mound but for now, i’m just a lazy boy big dreaming in my la-z-boy in the clouds of smoke, been playin’ this marvin mama forgive me, should be thinkin’ bout harvard but that’s too far away, [my peoples] are starving ain’t nothin’ wrong with aimin, just gotta change the target . . . you’re now in a game where only time can tell survive the droughts, i wish you well . . . survive the droughts? i wish you well? how sick am i? i wish you health i wish you wheels, i wish you wealth i wish you insight so you could see for yourself having a smoke and dreaming with your friends about one day making money deferred dreams in the ghetto poor people also feel the urgent need to stake a claim and find a place in the world realities of poverty that redirect positive life goals toward here and now, concrete financial realities. also speaks to the fact that ambition is still present in the heart of a street hustler—but lack of options, lack of critical thought, lack of principles, etc. have caused him to redirect his dream time undoubtedly will run out for a street hustler a person living in poverty is thirsty, his life itself is a drought so i wish him a well (a water supply), but i also wish him well (to be okay and to do well in life), i wish him the things that will transport him out of poverty: wheels, wealth, insight jenkins finally mentioning his talent, his community experience, and his intelligence (winfrey, ). jay-z’s intelligence is beginning to peak through the cur- tains of the stereotypes. on a recent taping of real time with bill maher, bill maher presented jay-z with the printed body of his work, which composed an encyclopedia-length text (sutton, ). on the show, the two men discussed the depth of writing involved in hip-hop. maher shared his personal opinion that the lyrics of hip-hop music are much more important than those found in other forms of popular music because of their centrality to serious social issues and political problems. on the american gangster album, jay-z dem- onstrates creativity first in the way in which the album is constructed: each song is a progression that, when heard from beginning to end, tells the classic story of the rise and fall of a hustler. and within each song, the artist displays his mastery of lyrical style and content. as demonstrated in table in “american dreamin’” (carter, ), his literary skill with plays on words and metaphors, the rich meaning of his words, and his delivery make him exceptional. jay-z is an artist largely known and applauded for the fact that he does not write his rhymes on paper. other, younger artists, like lil wayne, have also begun touting memorizing and freestyling as a show of their genius (rodriguez, ). however, when one examines the complexity of the lyrics that artists like jay-z, talib kweli, nas, dead prez, ras, mos def, black thought, andre , rakim, and tupac have written, it is apparent that it is not how they record their music but rather the rich content and meaning of the lyrics that make their work a literal stroke of genius. in the article “mr. nigger: the challenges of educating african american males in american society” (jenkins, b), i discuss hip-hop’s merit as an alternative space of intellectual inclusion for black men. in the article, i pro- vide the following praise for the content in some hip-hop songs: the lyrics of these artists summarize in less than five minutes and in a poetic form many of the key aspects that researchers have come to align with the black male experience in america—poor health, negative interactions with the criminal justice system, love for family, social oppression, violence, social rage and frustration, community leadership and activism, depression, prison industry complex, enslavement, unem- ployment, poverty, and the need for communal and self love. (p. ) and beyond the content knowledge being offered forth through their music, as previously mentioned, the writing talent is noteworthy. throughout each song, the writers have used metaphors, similes, puns, and various forms of word play. their work production also has merit in its mastery of the journal of black studies xx(x) schemes and tropes of stylistic writing and speaking. in many ways, hip-hop music is a contemporary continuation of the great intellectual tradition of the harlem renaissance. the strong social, economic, and political critiques of many rappers echo the artistic resistance of langston hughes’s works, like “let america be america”: i am the poor white, fooled and pushed apart, i am the negro bearing slavery’s scars. i am the red man driven from the land, i am the immigrant clutching the hope i seek— and finding only the same old stupid plan of dog eat dog, of mighty crush the weak. i am the young man, full of strength and hope, tangled in that ancient endless chain of profit, power, gain, of grab the land! of grab the gold! of grab the ways of satisfying need! of work the men! of take the pay! of owning everything for one’s own greed! (hughes, ) the ethic behind songs like tupac’s ( ) “changes” and mos def’s (smith, b) “mr. nigger” conjures up memories of claude mckay’s ( ) “outcast”: for the dim regions whence my fathers came my spirit, bondaged by the body, longs. words felt, but never heard, my lips would frame; my soul would sing forgotten jungle songs. i would go back to darkness and to peace, but the great western world holds me in fee, and i may never hope for full release while to its alien gods i bend my knee. something in me is lost, forever lost, some vital thing has gone out of my heart, and i must walk the way of life a ghost among the sons of earth, a thing apart. for i was born, far from my native clime, under the white man’s menace, out of time. undoubtedly, harlem renaissance artists are the reason hip-hop artists have a platform to speak so freely today. the foundation of creative energy, jenkins passion, and courage that this group of intellectuals created during the renaissance ushered in a new form of political license for writers, poets, and musicians. everyone was included in the cause—everyone was considered to be a thinker. using a new genre of music, hip-hop artists are still cri- tiquing, reflecting, and artistically navigating the racial and class-based experience in america. they carry forward the torch. but it also must be said that in proving or arguing hip-hop’s worth as an intellectual art form, it should not have to be similar to another art era that is more respected and more familiar. while recognizing and appreciating the family tree and the artistic genealogy, we must still allow the new generation to stand on its own two feet. hip-hop is intellectually worthy simply because of its con- tent. its worth does not lie solely in the fact that it continues a tradition. its worth does not rest solely in the fact that it mirrors the resistance of the past. it is worthy of intellectual appreciation simply because truth expressed through a politic of imagination and creativity is worthy of praise whenever it is exhibited. a call to move beyond pathology: expanding the conversation there is so much potential for the intellectual identity of the artist and the broad consumer culture that identifies with hip-hop. identity in hip-hop cul- ture has been and in small pockets continues to be about absolute excellence, a strong sense of self-efficacy, and a pursuit to be the best. hip-hop is a cultural space where individuals who have been kicked out of schools, locked out of opportunity, and imprisoned in oppression have created a space where they can shine, excel, and be great (jenkins, b). in their music, artists from krs-one to the roots to jay-z have always talked about their great- ness, their skill, and their aim to be the best. it is questionable whether this ethic of excellence has been clearly seen through the smog of stereotypes obstructing our view. as bell hooks ( ) points out, “now more than ever before, the dark forces of addiction, of violence, of death seem to have a more powerful grip on the black male soul than does the will to live, to love, to be healthy, and whole” (p. ). this is a situation our society has created. and it is up to us to fix it. we must love the black male mind that we have so severely neglected, ignored, and demented. the strength of our families, the health of our communities, the diversity of our companies, and very clearly, the population of our prisons all depend on the strength of black male self-efficacy. journal of black studies xx(x) it is time to expand the traditional conversations that we have been hav- ing about identity in hip-hop. moving beyond pathology means artists mov- ing beyond glorifying one-dimensional and often fake identities in their music and lyrics. first, artists need to see themselves fully. i am suggesting that artists need to love and appreciate their minds and see themselves as more than the kid that made it out, more than the guy that used hip-hop as a hustle, and more than the wind-up doll playing whatever role society demands for a dollar. additionally, the ways in which media and entertainment corporate struc- tures market artists also requires criticism, protest, and renewal. consumers need to show up mentally and physically in the marketplace. not only should we evaluate how our beloved culture is being molded, but we must also com- municate our criticism via retail and online stores. we literally buy into the identity of the ignorant, oversexed thug every time we buy a song. and to move beyond pathology, we as consumers and critics of hip-hop need to indeed become more critical in our thinking about the art form. at the same time that we hold some artists accountable for the harmful art that they pro- duce, we also have to ensure that we hold up those artists that are shining examples of brilliance. we have had many necessary conversations in the past few years about what is wrong with hip-hop music. it seems both neces- sary and timely to now suggest that we also examine how hip-hop can heal the self-concept of our young people. we have talked misogyny and vio- lence. and it is a conversation that needs to continue. but lets add to the agenda. to borrow the framework of hip-hop legends salt-n-pepa, let’s talk about intelligence. declaration of conflicting interests the author declared no potential conflicts of interests with respect to the authorship and/or publication of this article. funding the author received no financial support for the research and/or authorship of this article. references angry independent. 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( , october). oprah talks to jay. o magazine, p. . bio toby s. jenkins is an assistant professor of integrative studies and higher education at george mason university. psychiatric bulletin ( ), , - sketches fromthe historyof psychiatry a cat, surpassing in beauty, and other therapeutic animals patriciah. allderidge,archivist and curator, the bethlem royal hospital, beckenham, kent br bx in the illustrated london news published an engraving of a male ward in bethlem hospital, in which two slightly wary looking whippets or small greyhounds are wandering among the patients, while one of them keeps a watchful eye on a smug cat seated beside the chair of a chess player. at intervals along the walls are birdcages and goldfish bowls, all with their appropriate occupants. another engrav ing shows a female ward, where similar cages and bowls can be seen hanging between the windows, though the free-range livestock is absent. each room is also furnished with a huge aviary reaching from floor to ceiling. these particular dogs may have belonged to the resident physician, dr (later sir) charles hood, who certainly owned a pair of this breed: but birds and animals were by this time regarded as a normal part of life in the hospital. in the article which accompa nies the engravings we are told: "in the centre of the gallery wall there is a complete aviary full of joyously-caroling birds; and these little songsters seem to possess much power in raising the sometimes a men's ward in bethlem hospital, i , from 'the illustrated london news'. (bethlem royal hospital archives and museum). drooping spirits and soothing the troubled minds of the unhappy persons who dwell here." the women's ward is "prettily painted, well carpeted, cheerfully lighted, and enlivened with prints and busts, with aviaries and pet animals". in the men's ward "there are fewer flowers, and similar little elegancies, but the comforts are the same, and there is the same fondness manifested for pet birds and animals, cats, canaries, squirrels, greyhounds &c ... [some patients] pace the long gallery incessantly, pouring out their woes to those who will listen to them, or, if there be none to listen, to the dogs and cats ..." (illustrated london news, and march ).bethlem's well-stocked wards were the urban hos pital's answer to recommendations such as those of dr w. a. f. browne, medical superintendent of the montrose asylum, who described how the grounds of lunatic asylums could be given a more pleasing and less prisonlike appearance: "these places should be planted, have a fountain; a portion of ground prepared as a bowling-green; they should be stocked with sheep, hares, a monkey, or some other domestic or social animals ...". this passage had been quoted by the charity commissioners in a highly critical report on the dreary conditions endured by bethlem's patients in the s (report of the commissioners for inquiring concerning charities, ), and it represented a view which was coming to be widely accepted. a few years later john conolly made similar suggestions: "a bowling-green, a cricket-ground, seats under the trees, and the encouragement of ball-playing ... are all worth remembering; and buildings containing birds of various kinds, and tame animals, will be found to interest many of the patients. a piece of shallow water, with ducks and other aquatic fowl, would also give them pleasure" (conolly, ). as in so many things, this aspect of institutional life seems to have been pioneered by the retreat. already by , the superintendent here had "endeavoured to furnish a source of amusement, to those patients whose walks are necessarily more circumscribed, by supplying each of the courts with a number of animals; such as rabbits, sea-gulls, hawks and poultry. these creatures are generally very familiar with the patients: and it is believed they are not only the means of innocent pleasure; but that the intercourse with them, sometimes tends to awaken the social and benevolent feelings" (tuke, ). this observation will not surprise those who, more than a century and a half later, have just disco vered that animals can have a 'humanising' effect on the institutionalised: only the choice of fauna seems slightly eccentric. york, more than miles flight from the sea even for a crow, can hardly have been a natural habitat for sea-gulls; and the consequence of keeping both rabbits and hawks without adequate allderidge - . â€¢¿�- 'epitaph of my poor jack, squirrel': poem written in bethlem hospital by james hadfield, . (bethlem royal hospital archives and museum). segregation seems unlikely to have furnished much amusement for the rabbits. the household animals of the bethlem wards in the s had, however, a long tradition of their own, though one which had previously owed more to individual enterprise than officiai policy. an early and well publicised keeper of pet animals was james hadfield, whose attempt to shoot king george iii, in , had set in motion the first criminal lunacy legis lation. he spent nearly years confined in bethlem, where he was seen by many visitors including the frenchwoman, flora tristan. "we stayed some time with him; his conversation and his habits reveal an unreserved tenderness, a loving heart, an absolute need for affection: he has had in succession two dogs, three cats, birds, and finally a squirrel. he loved these animals dearly, and suffered grief at seeing them die; he has stuffed them himself, and has set them up in his room. these remains of the creatures which he loved haveeach an epitaph in verse, witnessing to his regrets. that to his squirrel is surmounted by a coloured draw ing of his lost friend. i must say also, that he makes a little business of his feelings, which brings him in a nice enough revenue; he distributes these epitaphs to visitors, who give him a few shillings in return ..." (tristan, ). in the historical collection at bethlem are three of these verse epitaphs written on the death of his squirrel 'jack', in , two of which are charmingly illustrated in watercolour. sketches from the history of psychiatry cats' christmas-painted on a mirror by louis wain as part of the christmas decorations at napsburv hospital in the s. (bethlem royal hospital archives and museum). a contemporary and associate of hadfield, bannister truelock, went one better. according to that deplorable but invaluable publication sketches in bedlam, while he was confined in bethlem he was "permitted to breed birds, and allowed to sell them; he has a great number of canaries and other singing birds, in places neatly fitted up, which he keeps in great order" (sketches in bedlam, ). the same source tells us of charles goldney, an old patient who "as an amusement" looked after the ducks on the pond, and took a particular interest in both the ducks and pigs, all of which he believed to be his own property. these creatures were actually being kept for consumption rather than for the amusement of the patients (a circumstance which caused him par ticular concern when they periodically disappeared into the kitchen), and it would appear that goldney had chosen for himself the role of duck-keeper. in a similar way, other patients must have made opportunistic use of a working cat population in order to acquire their own pets. the most striking example is james norris, whose confinement from to , riveted into an iron harness and chained to a post by an iron collar, has created one of the most horrific icons in bethlem's history. questioned by the parliamentary committee on madhouses as to how norris had employed him self, the apothecary john haslam replied: "he read; i have supplied him with books myself, frequently. he had a cat which amused him; and he read thenewspaper" (report from the committee on madhouses in england, ). if ever a cat deserved recognition for services to humanity, it must surely be the one which befriended james norris in the bethlem cell where his fellow men had abandoned him. norris is by no means the earliest recorded expo nent of the human/animal relationship in psychiatry, even in england. the poet christopher smart, though never in bethlem, was confined in st luke's hospital during an attack of insanity from - , and then for several years in a private madhouse at bethnel green run by mr or mrs potter. here he wrote his glorious paean to the whole of living cre ation. jubilate agno, in which the tenderes! and most personal passage in this highly personal poem is the line section, well known to anthologists of cat literature, beginning "for i will consider my cat jeoflry ...". smart writes of the cat in the present tense, and this and other references elsewhere in the poem, including the line "for i am possessed of a cat, surpassing in beauty, from whom i take occasion to bless almighty god", seem to confirm that jeoffry was actually present with him in the madhouse. further afield and two centuries earlier, the poet torquato tasso had similarly found consolation in his confinement. he wrote two sonnets about the cats of the asylum of st anne at ferrara, where he spent seven years from . nearer to home, yet another poet who suffered a protracted period of mental dis order, from which he gained respite in the com panionship of animals, was william cowper. during his gradual emergence from many years of severe depression in the s, "before his mind was sufficiently recovered to employ itself on literary composition, it sought, and found, much salutary amusement in educating a little group of tame hares" (hayley, ). cowper, though he had during a previous attack spent some time in dr nathaniel cotton's private madhouse at st albans, was at this time at home at olney. like the rest of these earlier examples, his animal therapy was self-prescribed. "on his expressing a wish to divert himself by rearing a single leveret, the good-nature of his neighbours supplied him with three. the variety of their disposi tions became a source of great entertainment to his compassionate and contemplative spirit." (hayley, ). cowper himself later immortalised one of these hares in the poem 'the task', and also wrote of them in the gentleman's magazine. the deliberate introduction of animals into the th century asylums was continued well into this century through the development of the asylum farms; but eventually the wheel turned, therapeutic fashion changed, and animals of all kinds disap peared almost entirely from the scene. there are exceptions where some element of the tradition ap pears to have survived unbroken: at napsbury, for example, the cat colony which still exists today must include direct descendants of the cats which louis wain knew and drew there during the s, and whose own ancestors must have predated him by many years. in the redesignated 'mental hospitals' in general, however, there was little room for animal life. whatever the reasons, the symbolism of this renaming cannot be ignored in assessing present atti tudes. the asylum was a place of refuge and support for the afflicted: in the more sterile environment of the hospital, where scientific medicine holds sway, the role of animals is likely to be confined to the research laboratories. now, however, the wheel is making another, if painfully slow, turn, and the reintroduction of ani mals into the institutional environment is beginning to take place under the very cloak of scientific respec- tibility itself. in britain the society for companion animal studies (scas) is now years old, and flourishing. it has many counterparts in other countries: delta in the usa, delta australia, habac (the human animal bond association of canada), afirac in france, iemt in austria, the human-animal contact study group of south africa (hacsgsa), and now iahaio (the international association of human-animal interactions organisations). suddenly the study of 'human/companion animal inter-relationships' is big business worldwide, providing opportunities for conferences in pleasant places such as monaco, and a whole new breeding ground for scientific papers. according to the scas membership leaflet, the "potential emotional and educational benefits" of pet ownership are busily being "confirmed by the results of research". studies have "demonstrated the potential therapeutic value of pets in treating an extraordinary variety of social and psychological problems"; and "pet-facilitated therapy" has achieved the status, at least in fashionable circles, of being referred to casually as pft. guidelines have been produced for introducing animals into insti tutions (no more haphazard mismatching of hawks and rabbits in the new scientific era, and definitely no privately owned squirrels); and among a number of practical schemes, a bunch of friendly dogs known as pat (pro-dogs active therapy) dogs visit various establishments to cheer up the residents (many of whom may have had to send off their own much loved dogs to their deaths before they themselves could be admitted, in conformity with the rigid rules of last year's ideology). of course this is all to the good, and a great step forward towards the more enlightened attitudes of the past: though there is still a long way to go before even the minority of patients strike so lucky as my own father, whose shetland sheepdog visited him regularly in hospital throughout the last weeks of his life, and was in the room with him when he died, not because any 'guidelines' had been issued, but because it never occurred to the kind and sensible nurses that there was any reason why she should not. somehow it would seem more reassuring if all the animals which are now infiltrating their way back into the lives of deprived and distressed people were being allowed in for the same simple reasons which operated in my father's case, because some people allderidge like having them around and are made happier by their presence, rather than because "research has yielded evidence that pets can have directly beneficial effects on human health, including improved one- year survival rates following heart attacks, and beneficial changes in heart rate and blood pressure"; or because in a particular institution an active pro gramme of "pet-facilitated therapy" is being pursued by someone anxious to read a paper at the next iahaio conference. for the time being, perhaps it does not matter very much why they are there so long as they are there: but for anyone with a sense of history there is always the nagging doubt that by the time their own turn comes round for a spell of pft, the wheel of fashion may have moved on again. some eager team of research workers in quest of scientific truth and further publications for their cvs may have discovered that interacting with cats and dogs can have harmful side effects, particularly on rats and mice, and all therapeutic animals may have been withdrawn as a precaution. one thing is certain: whatever may have been the effect on christopher smart's blood pressure, the world of literature was immeasurably enriched because he was possessed of a cat surpassing in beauty ("for there is nothing sweeter than his peace when at rest./ for there is nothing brisker than his life when in motion."). it would not have been at all the same, if he had had to manage on half an hour a week interacting with a pat dog under careful supervision. references conolly,j. ( ) the construction and government of lunatic asylums and hospitals for the insane. reprinted with an introduction by r. hunter and i. macalpine ( ). london: dawsons, p. . hayley,w. ( ) the life and posthumous writings of william cowper, vol. i. london, p. . illustrated london news, and march . report of the commissioners for inquiring concerning charities, , part vi ( ). p. . report from the committee on madhouses in england ( ). p. . sketches in bedlam: or characteristics traits of insanity ...by a constant observer ( ). pp. , . smart,c. 'jubilate agno'. first published as rejoice in the lamb. a song from bedlam. edited with an introduction and notes by william force stead. london: jonathan cape, . tristan,f. ( ) promenades dans londres par mme flora tristan. paris/londres, p. . ture,s. ( ) description of the retreat. reprinted with an introduction by r. hunter and i. macalpine ( ). london: dawsons. p. . bew .docx imagery beauty in the application of microscopic material forms du yiming south china university of technology, institute of micro-science arts, guangzhou, china, c keywords: microscopic material form; imagery; imagery beauty abstract: with the diversified development of art forms, the combination of art and science shows a booming trend. applying the microscopic material form to the creation of paintings is beyond the boundaries of vision. it is a comprehensive experience of sensory and a new expression of the combination of subjective emotions and objective objects. this way of creation is both improvised and well designed. this paper reflects the cultural connotation of the application of microscopic material form by analyzing the microscopic material form and image beauty. at present, the two disciplines of science and art are developing more and more closely. scientific art and artistic science have become an irresistible trend. through the observation of scientific instruments, such as microscopes, the microscopic world has become a new field in which people continue to expand their visual boundaries. microscopic science is not only a science and technology subject,it has opened up a new world in the field of art. this field of vision has an unexpected visual effect. it presents an image beauty which is completely different from the macro world. its texture and structural beauty also open a new door for artistic creation, providing unlimited possibilities. these microscopic forms give people a visual and spiritual shock with their unique charm, which allows people to rethink macro and micro. artistic creation no longer only seeks material from the macroscopic world which is visible to the naked eye, but instead looks at the strange microscopic material world. applying the microscopic material form to the creation and design of painting, as an abstract artistic expression, this language is more like a new expression of the combination of subjective emotions and objective objects. the point, line, and surface of the shape are reflected in a new structure, rather than a complete replica. this kind of creation has gone beyond the boundaries of vision and has become a comprehensive experience of perception, blending into the design of images and textures. it includes improvisation and well-designed art, combines art and science to express the inner world of the creator. therefore, the beauty of imagery in the application of microscopic material forms has become an indispensable link in the study of microscopic art. . introduction . imagery the influence of a long history and culture has produced a unique aesthetic taste of chinese art. the fusion of objective objects and subjective emotions forms a unique artistic language: imagery. as a kind of aesthetics with rich connotations in china, it appears in all fields of art. the origin of the imagery concept can be traced back to the "yi zhuan": "the saints set up image to express idea, set up divinatory symbols to express the truth, and make words to express their opinion." it means: saints create divinatory symbols to express the meaning of god, to show the truth, to express viewpoint. the "imagery" refers to the will of the holy body, and "image" refers to the symbolic phenomenon. although it is far from the aesthetic category, it uses "image" as a symbolic system that can express opinions for the descendant. and the formation of the "image" aesthetic concept has laid a certain foundation of later research. the first time to combine "meaning" and "image" was the "lun heng·luan long pian" in the han dynasty: "on the canvas paints the image of bear, elk, tiger, leopard and so on. the cloth is named hou, the meaning of the rite is precious. the name depends on the meanings." it is to say: international conference on culture, literature, arts & humanities (icclah ) copyright © ( ) francis academic press, uk doi: . /icclah. . -- -- draw pictures of bear, elk, tiger, leopard and other beasts on the canvas, let the emperor shoot the bear, the princes shoot the elk, the ministers shoot the tiger and leopards, the gentlemen go to shoot the deer and the pigs. the beasts they can shoot shows their bravery. the canva with the image of the bear on it is called hou, it means overthrow the fatuity. the name of the canvas is according to the ritual system, and the ritual system is conveyed from the images on the canvas. but the word "image" here refers to the animal pattern painted on the ancient archery target, it stands for the symbolic image. the concept of "imagery" was first proposed in liu wei's "wen xin diao long·shen si pian" in the southern and northern dynasties, and it also established the aesthetic category. in the article it says: “the master of solo is watching the image and carrying the weight at the glimpse of the object." it means that a uniquely crafted craftsman can swing an axe in the image of the heart. the "image" here refers to the image formed by the thoughts, which means that the image of the object must be integrated with the creator's own interest and emotion. in the art creation after this, the concept of imagery was widely used to form a unique aesthetic consciousness of chinese art. “imagination” has also become an important criterion for evaluating art works, and has become a basic aesthetic category. . imagery beauty the so-called "meaning" is the inner thought, and the so-called "image" is the external representation and expression. the image is to express the spiritual pursuit that exists at the ideological level with concrete manifestations. this form of creative expression is not to reproduce the image of reality as seen on the painting, nor to subconsciously smear beyond the realistic image of the real thing, but to establish a spiritual image from abstract thinking and select appropriate representations. the image comes with a smile. the picture itself may be subtle, but the author's thoughts have already reached the realm of the image in the painting. in the art work that truly stands for art, the beauty of imagery is often reflected in people's own perceptions. this kind of sentiment is a collision between the experience of nature and the course of one's own thoughts. the spark of the excitement is instantaneous, and retaining this great impulse by means of the image will be expressed on paper, giving the viewer a shock. the space and the shock of the visual, this is the beauty conveyed through the image. "a thousand readers have a thousand hamlet." each viewer has different feelings in the face of the same piece of work because of his own cultural knowledge and life background. the beauty of imagery is an experience of "only can be understood, cannot be said" under the guidance of thinking, and is the subjective feeling of the aesthetic subject to the aesthetic object. the soul collision of the spiritual world caused by these visual feelings, is it not the beauty of the imagery of paintings? . microscopic material form in the process of scientific development and progress, the emergence of the micro world has provided artists with new situations and modes of thinking. through the micro-science, the door of the micro-art world has been opened. the micro-forms presented have their original intentions, and they can all be given the beauty of images through the display of micro-forms. expanded the source of painting materials for artists. for everyday materials captured by the naked eye or captured by ordinary imaging, micro-scientific research has seen a broader and deeper world that is less familiar. the huge microscopic material world, the imagination and creative inspiration brought about by artistic creation cannot be replaced by other feelings. applying the forms discovered by micro-science to art creation and design, promoting interdisciplinary research, enriching the theoretical knowledge combined with micro-science and artistic creation helps to construct a comprehensive and systematic theoretical system, inspiring viewers from art works. it is of great significance to think about the nature of life and life, and to scientifically and scientifically. the application of microscopic material forms makes the composition of the picture clever, the color, space and shape are very mysterious, and the small part is magnified in the grand natural environment, giving the natural small objects a grand sense of the universe, implanting the spirit meaning, through the passenger viewing objects express cultural ideas and artistic spirit. the use of -- -- microscopic forms for artistic creation not only shows the combination of science and technology and artistic creation, but also a new way and method in the field of painting creation. the works created by it will inevitably enrich the diversity and contemporaneity of today's painting art, create new and far-reaching status and exert huge influence. . the embodiment of image beauty in the application of microscopic material form . possibility of microscopic material forms’imagery ye lang said in "the beauty in imagery - the basic principles of aesthetics": "the ontology of art is an aesthetic image that is a complete and meaningful sensible world. art does not provide people with a valuable instrument, nor does it use a form of proposition to provide people with a truth about the world, but to present an image world to people, so that the audience can have a sense of beauty.” he believes that art and beauty are inseparable, and the difference between art and non-art depends on if the work can present an image world. the microscopic material form can trigger people to perceive the rhythm of life, experience the tension of natural life, explore the traces of the thrilling life activities, and trigger the philosophical thinking of the meaning of life in the depths of people's minds. the tiny structures, textures, tissues, and so on in the microscopic material form give people a mysterious senses and the possibility of microscopic material forms ’imagery, because of its unique existence form and structural outline. such as: figure is the cross section of the human blood vessels under the microscope, it presents a beautiful color and a mysterious arrangement. the viewer sees a wonderfully structured world that has nothing to do with human blood vessels. beyond human perception, abstract and complex, with a natural and vivid structure. exaggerated and bright colors, the contrast is strong but presents a unique harmony, which causes the viewer to think about life. it is also like the vast interstellar, mysterious and profound, giving people the enlightenment of the origin of life. such psychological activities have inspired the artist's creative inspiration and laid the foundation for the search for creative content and artistic expression. figure human blood vessel cross section under the microscope figure is the tiny crystals of oxycodone (narcotic drugs), it seems like the shape of flying petals and dancing bees under the microscope. the colors are harmonious and unified, the structure is exquisite and rich, and it is natural and vivid. the structure and color of the microscopic material form presents a light and lively life rhythm, which provides reference for artistic creation and reference for imagery beauty. -- -- figure oxycodone (narcotic drugs) tiny crystals figure is the crystal structure of the copper under the microscope, the exterior shape is clear, and the sharp facet is sharply turned. applying this microscopic material form to artistic creation, it expresses the sharp and hard texture of metal products, emphasizing the perseverance personality just like the bronze sword. figure copper crystal structure under the microscope the numerous microscopic material forms, each of which can be explored for its unique aesthetic styling and emotional orientation. the composition of similar geometric elements awakens our desire to seek knowledge from the microscopic material world. the microscopic material, the external form is rich and varied, and the inner also carries the mysterious visual impact. they trigger the viewer's philosophical thinking on the nature of life, the perception and resonance of the rhythm of life, manifests the possibility of microscopic material forms’ imagery. . microscopic material form and image beauty hegel put forward the famous proposition in his "aesthetics": "beauty is the perceptual manifestation of the concept." he believes that beauty is the idea, beauty must be true, and it is a perceptual expression of truth. the idea itself exists only as a universal truth. it must be expressed in the concrete form of the sensible thing, and it becomes a work of art that can be appreciated by people. zhu guangqian, a famous contemporary esthetician, said: "the world of beauty is purely an image world." zong baihua, an esthetician, once said: "the subjective life sentiment blends with the objective natural scene, making a flying, leaping, lively spiritual environment." this emotional -- -- point that has been repeatedly scrutinized by estheticians is the beauty of artistic imagery. as ye lang said in the article "america in the image", this kind of beauty "is not a physical reality, nor an abstract conceptual world, but a complete, full of meaning and full of funny world." the application of microscopic material morphology under microscopic scientific research is to use modern science and technology to extract the color, shape, structure and texture of microscopic materials, and apply them in the artistic creation. this process is the author's sensibility creation combined with his own thoughts and understanding. in this process, the “truth” of microscopic material is conveyed to the viewer through the “sensible” understanding of the creator, forming a series of beautiful artistic labor. . conclusion micro-science art is using the high-tech means to discover the mysterious and bizarre microcosm which is beyond the naked eye, reveal the microscopic natural form, and extract the aesthetic elements of microscopic form, and create unique microscopic artistic creation. this interdisciplinary experimental creation poetically explains the spiritual beauty of the objective material world. the imagery beauty of microscopic material form is the transcendence of the real thing, the sublimation of the figurative thing, it is the new soul of the art work. the works are not spoken, but the aesthetic image makes the works reflect the strong spiritual power from the concrete objects. acknowledgement this research is based on the study of micro-science arts form (serial number: c ). references [ ] zhang shiying. the philosophical ontological foundation of the beauty of imagery [j]. chinese literature review, ( ): - . [ ] ye lang. beauty in imagery——abstract of basic principles of aesthetics [j]. journal of peking university (philosophy and social sciences), , ( ): - . [ ] yu zhihong. microscopic natural forms of imagery [j]. journal of nanjing university of the arts (art and design edition), ( ): - . [ ] shang xingjie. life is beautiful but not words--analysis of decorative language in microscopic imagery of life [j]. art and design (theory), , ( ): - . [ ] hu jing. the image creation of chinese painting art [j]. art education, ( ): . -- -- deep learning for facial beauty prediction information article deep learning for facial beauty prediction kerang cao , kwang-nam choi , hoekyung jung and lini duan ,* department of computer science and engineering, shenyang university of chemical technology, shenyang , china; caokerang@syuct.edu.cn ntis center, korea institute of science and technology information, seoul , korea; knchoi@kisti.re.kr department of computer engineering, paichai university, daejeon , korea; hkjung@pcu.ac.kr * correspondence: liniduan@ .com received: july ; accepted: august ; published: august �� abstract: facial beauty prediction (fbp) is a burgeoning issue for attractiveness evaluation, which aims to make assessment consistent with human opinion. since fbp is a regression problem, to handle this issue, there are data-driven methods for finding the relations between facial features and beauty assessment. recently, deep learning methods have shown its amazing capacity for feature representation and analysis. convolutional neural networks (cnns) have shown tremendous performance on facial recognition and comprehension, which are proved as an effective method for facial feature exploration. lately, there are well-designed networks with efficient structures investigated for better representation performance. however, these designs concentrate on the effective block but do not build an efficient information transmission pathway, which led to a sub-optimal capacity for feature representation. furthermore, these works cannot find the inherent correlations of feature maps, which also limits the performance. in this paper, an elaborate network design for fbp issue is proposed for better performance. a residual-in-residual (rir) structure is introduced to the network for passing the gradient flow deeper, and building a better pathway for information transmission. by applying the rir structure, a deeper network can be established for better feature representation. besides the rir network design, an attention mechanism is introduced to exploit the inner correlations among features. we investigate a joint spatial-wise and channel-wise attention (sca) block to distribute the importance among features, which finds a better representation for facial information. experimental results show our proposed network can predict facial beauty closer to a human’s assessment than state-of-the-arts. keywords: deep learning; facial beauty prediction; convolutional neural network . introduction as a burgeoning issue [ ], facial beauty prediction (fbp) has attracted more and more attention from researchers and users, which is a comprehensive topic of face recognition [ , ] and comprehension [ – ]. an example of an fbp problem can be demonstrated in figure . there are application potentials for fbp with attractiveness, such as makeup recommendation, and face beautification. in fbp problem, facial features play an important role for assessment. after extraction, the features are explored and summarized for aggregate analysis. to find a better representation of facial features, there are various data-driven models for fbp with hand-crafted or adaptive learned descriptors [ – ]. with extracted features, these models perform the assessments with elaborate predictors, which are trained in a statistic manner. lately, deep learning has been proved as an efficient tool for signal and image processing [ – ]. the revival of deep learning methods, especially, convolutional neural networks (cnns), provides a new perspective for fbp problem. cnn performs much better performances in information , , ; doi: . /info www.mdpi.com/journal/information http://www.mdpi.com/journal/information http://www.mdpi.com https://orcid.org/ - - - https://orcid.org/ - - - http://www.mdpi.com/ - / / / ?type=check_update&version= http://dx.doi.org/ . /info http://www.mdpi.com/journal/information information , , of plentiful computer vision tasks than traditional methods [ – ], such as text localization [ ], image classification [ ], facial landmark regression and analysis [ , ], emotion recognition [ , ], time series forecasting [ ], and semantic segmentation [ ]. with the adaptive feature extraction and exploration, cnn demonstrates superior capacities on the high-level computer vision tasks. to our best knowledge, alexnet [ ] is the first cnn-based method for real-world image recognition, which was proposed for image classification task in imagenet. after alexnet, vggnet [ ] explored a deeper and wider design for better feature exploration and network performance. there are various effective network designs for better performance on different tasks, which lead to a blossom of deep learning. more beautiful less beautiful figure . an example of facial beauty prediction. from top to the bottom, there are four kinds of facial images for prediction: asian female (af), asian male (am), caucasian female (cf), and caucasian male (cm). from left to the right, the predicted ranks are decreased gradually. resnet [ ], proposed by he et al., has turned out to be a remarkable design pattern for cnn architectures. while building a deeper network, there is gradient vanishing problem which limits the performance. in resnet, a shortcut is designed as bypath, connecting the inputs and outputs for better gradient transmission. the component design with shortcut is termed as residual block, which aims to learn the residual information from main path. based on the residual learning, it is able to build a very deep network. there are varieties of resnet focusing on efficient network representation. in resnext [ ], group convolutions were introduced to introduce the cardinality of the network, which means the size of transformations. from the investigation, it is more efficient to improve the cardinality than depth and width. resnext holds a similar structure to inceptionnet [ ]. however, there are identical topology structures in resnext, which reduce the design burden. with the splitting-transformation-merging strategy, resnext achieved competitive performance compared to resnet with much fewer parameters. resnest [ ] is another effective design derived from resnet. with channel separation and attention, resnest block designs several identical cardinals in the computation unit. similar to senet [ ] and sknet [ ], there are channel attentions in each cardinal unit for better feature map representation. considering the inherent correlation of different features, resnest has become state-of-the-art for image recognition and beyond. residual connection and its varieties demonstrate the superior performance of network representation ability. to build the network deeper and establish a more robust gradient flow, residual-in-residual (rir) is proposed by grouping residual blocks with a higher level shortcut. with the high level residual connection, gradient and information will be transmitted from the information , , of shallow layers to the deeper. rir structure has proved its performance on image super-resolution [ ], restoration [ ], classification and other computer vision tasks, which turns out to be an efficient design pattern. besides effective network designs, some works focus on the inherent correlations of features. channel attention in senet is one of the successful mechanisms for finding better representation of features. in senet, information from different channels is evaluated by global average pooling and is processed by several full connection layers. besides channel attention, spatial attentions are introduced by considering the dual attention maps both on channel-wise and spatial-wise features. non-local attention [ ], which is a special pattern for global information consideration on features, has become a success for image restoration and comprehension. this paper proposes a novel cnn design for the fbp problem. in the proposed network, we investigate an rir block design with an attention mechanism. to build the network deeper, multi-level skip connections are introduced to compose a better gradient transmission flow. an attention mechanism is devised to find the inherent correlation among feature maps. in an attention mechanism, both channel-wise and spatial-wise attentions are considered for a better correlation representation. experimental results show that our network holds a better performance than other cnn-based methods, which is more consistent with the assessment of humans. the contributions of this paper can be demonstrated as follows: • we propose a network for the facial beauty prediction (fbp) problem. specifically, residual-in-residual (rir) groups are designed for building a deeper network. to devise a better gradient transmission flow, multi-level skip connections are introduced. • to find the inherent correlations among features, a joint spatial-wise and channel-wise attention mechanism is introduced for better feature comprehension. • experimental results demonstrate our network can achieve a better performance than other cnn-based methods and make the assessment more consistent with human opinion. . related works . . facial beauty prediction facial beauty acts as an essential influence factor in daily life. facial beauty prediction (fbp) has attracted more and more attention from researchers, which is a composite study of psychology, computer science, evolutionary biology, and so forth. recently, there are data-driven methods for the fbp issue, which adaptively extract the facial features and perform the analysis with defined mathematical models. the models are supposed to be consistent with a human’s assessment as much as possible. besides plentiful prediction methods, databases proposed for the fbp problem have also become a spotlight in this area. scut-fbp [ ], to our best knowledge, is one of the most popular open benchmarks widely used for evaluation. in scut-fbp , there are diverse face pictures containing both males and females. the ages of the persons vary from to , which acquires a large interval for a richer representation of real facial beauty situation. there are asian females, asian males, caucasian males and caucasian females in scut-fbp , resized to × resolution. the scores are ranked by volunteers between – , meaning the attractiveness from low to high. . . convolutional neural networks convolutional neural networks (cnns) are one of the most remarkable successes in the deep learning area, which demonstrate superior performances on a large amount of computer vision tasks, such as detection [ – ], denoising [ ], recognition [ , ], and better feature representation [ – ]. to our best knowledge, alexnet, as the champions of the imagenet competition in , is one of the successful cnn designs developed on gpu. after alexnet, there have been numerous efficient designs for better performances, composed of wider or deeper networks with elaborate and fancy information , , of layer connections. vggnet, which is widely applied for various gan-based works, is one of the representative design patterns for deep networks. inceptionnet proposed by google is another effective design which achieved the first prize of ilsvrc . in inceptionnet, the authors designed an inception module to improve the parameter utilization. the inception module applied × convolutional layers to organize the information across different channels. features from convolutional layers with different filter sizes and max-pooling operations were aggregated by concatenation. by utilizing the inception module, the network improved the performance and avoided the over-fitting with more branches. furthermore, batch normalization (bn) and dropout strategies were applied in inceptionnet for training speed improvement. residual connection from resnet is another well-known structure for network design. in vggnet and inceptionnet, there is a limitation of network performance with the increase of network depth, which is caused by the gradient vanishing. to solve this issue, residual representation was introduced in resnet. the blocks were designed based on the residual learning, which makes it easier to learn the mapping between inputs and outputs. densely connection [ ], as another efficient design pattern for cnn, has become one of the popular choices for various tasks. different from resnet, densenet applied dense connections to connect features from shallow layers to deeper, which are more effective than residual connection. furthermore, features are reused in densenet via the concatenation of channels, which saves the parameters with fewer computation costs. . method as shown in figure , the proposed network holds a pyramid structure to progressively extract the feature from images. we devise a residual-in-residual group termed rirg to build the network deeper. there are five stages in the network. for each stage, the feature maps are down-scaled by max-pooling operation as the output. finally, a global average pooling is utilized to shrink the resolution to × . let us denote the input image as i , then for i-th stage, the operations can be described as, feati = ri rgin(· · · ri rg i (i i) · · ·), ii+ = maxpool(feati), ( ) where ri rgin(·) denotes the n-h rirg in i-th stage, and maxpool(·) denotes the max pooling operation. the proposed network will be introduced in the following manner. firstly, we will introduce the structure of the proposed rirg. moreover, the spatial-wise and channel-wise joint attention mechanism applied in rirg will be demonstrated in detail, which is termed sca. finally, the settings of the proposed network will de described with discussions. input image … … … … x x x x x x x x x x ? prediction maxpool rirg fc figure . network structure. there is a progressive design for facial feature exploration. with the increase of channel number, the resolution of feature maps will be decreased with a fixed ratio. information , , of . . residual-in-residual group rirgs are devised from the perspective that a deeper network will lead to better performance. since residual connection can survive from the gradient vanishing problem, residual-in-residual connections are introduced to pass the shallow features and gradients to deeper with a long shortcut. there are multi-levels in rirg to build the flow more effective. the design of rirg is shown in figure . conv relu conv 𝑥𝑥𝑖𝑖𝑖𝑖 𝑥𝑥𝑜𝑜𝑜𝑜𝑜𝑜 sca c o n v r el u c o n v sc a r ir b r ir b ……𝑥𝑥𝑖𝑖𝑖𝑖 𝑥𝑥𝑜𝑜𝑜𝑜𝑜𝑜 c o n v r el u c o n v sc a r ir m r ir m……𝑥𝑥𝑖𝑖𝑖𝑖 𝑥𝑥𝑜𝑜𝑜𝑜𝑜𝑜 (a) rirb (b) rirm (c) rirg figure . structure of proposed rirg. the rirg is built in a residual-in-residual way for better information transmission. the basic block in rirg, termed rirb, as shown in figure a, is composed of two convolutional layers with a relu activation and sca block. the residual connection in rirb can be regarded as the first level skip path, which connects the features at a distance of two convolutional layers. by stacking rirbs, the residual-in-residual module (rirm) is designed with a padding structure. the second level skip path is introduced to rirm connecting the input and output features. beyond the second level skip connection, residual-in-residual group (rirg) is devised in a recursive way like the rirm, which stacks the rirm as the main path with a same padding structure. the third level skip connection in rirg crosses a large spacing of convolutional layers, which makes the shallow features become deeper more efficiently. the rirg holds a similar structure to dense connection. if we expand the three-level residual connections, and regard the stacked layers as an entire operation, then the features from different layers are densely connected via residual learning. on one hand, the densely-like design is able to deliver the features and information more efficiently. on the other hand, the mixture of dense and residual connections reuses the features with limited parameters and computation complexity, which indeed improves the network performance. although the rir design can build an efficient information transmission pathway, it requires a large number of parameters and high computation complexity with the increase of network depth. from this point of view, we propose a modified convolution operation to substitute the vanilla layer. for each convolution step, there are two × convolution operations for channel squeeze and excitation, and one depth-wise convolution for spatial exploitation. the shrunken channel number is set as . with this substitution, the computation complexity and parameters will be substantially saved. . . spatial-wise and channel-wise attention the proposed spatial- and channel-wise attention mechanism (sca) is shown in figure . as shown in the illustration, there are two dual paths finding the spatial-wise and channel-wise attentions separately. there is a convolutional layer to demonstrate the explore the correlation from features in general. after exploration, two parallel bypaths exploit the different attentions independently. from the channel-wise attention bypath, the information from different channels will be evaluated by global average pooling. after pooling, two full connection layers with a relu activation is introduced to dig out the inherent correlation. finally, a sigmoid activation is devised for the non-negativity. information , , of r el u fc fc c o n v r el u d -c o n v d -c o n v a vg p o o l si g m o id si g m o id 𝑥𝑥𝑖𝑖𝑖𝑖 𝑥𝑥𝑜𝑜𝑜𝑜𝑜𝑜 figure . structure of proposed spatial- and channel-wise attention mechanism (sca). there are two paths for finding the spatial and channel attention jointly. after distribution, the addition of two features will be regarded as the output. similar to the channel-wise bypath, there are two convolutional layers with a relu activation to demonstrate the correlation of spatial-wise features, and a sigmoid activation is applied at the end of the processing procedure. different from the channel-wise bypath, there is no global pooling method for information evaluation. after extraction, the two attentions are multiplied with the input features, and the addition is regarded as the final result. the operation of sca can be described as, xsc a = conv(xin), ( ) xsc ac = σ(fc(relu(fc(avgpool(x sc a))))), ( ) xsc as = σ(dconv(relu(dconv(x sc a)))), ( ) xout = x sc a c ⊗ xin + x sc a s � xin, ( ) where σ(·) denotes the sigmoid activation, xin, xout denote the input and output features separately. ⊗ denotes the channel-wise multiplication, which allocates different weights to channels. � denotes the point-wise multiplication. dconv(·) denotes the depth-wise convolution. in the operation, xsc ac is a tensor with size × × c and xsc as is a tensor with size h × w × c, where h, w, and c denotes the height, width and channel number of the size of xsc a. . . network design the entire network is designed as follows. firstly, the input image is considered with size × × . then one convolutional layer expands the channel number to and maintains the resolution. there are n = rirgs after the convolutional layers for feature exploration, and a max-pooling operation is applied to decrease the feature size. for each rirg, there are five rirms, and five rirb for each rirm. there are k = stages in the network. in each stage, the channel number will be expanded by one convolutional layer at the beginning, and the size of features is halved by max-pooling at the end. after the stages, there is a global average pooling step to resize the tensors as × × . two fully connection (fc) layers with a relu activation is introduced to perform the prediction, and the output size of final fc is one, demonstrating the rank of facial beauty prediction. . experiment the network is trained on the scut-fbp dataset. to our best knowledge, it is the largest dataset for fbp problem up to now. we train the network for iteration with batch size as b = . the parameters are updated by adam optimizer with learning rate lr = e − , which is halved for every iterations. we choose l -loss as the loss function. notice that the input size of the information , , of scut-fbp dataset is × , we rescale the image size to × by bicubic interpolation for training and testing. . . results we conduct the comparison with diverse methods including geometric feature based and deep learning based methods—linear regression, gaussian regression, svr, alexnet, resnet- , and resnext- . the measurement indexes are chosen as pearson correlation, mae, and rmse. the dataset is split with the ratio . for training and . for testing. that is, % instances of the dataset are randomly chosen for training and the other % are for testing. the results are shown in table . pc demonstrates the pearson correlation, which is the higher the better. from the table, our network performs better than other works. with the higher pc, our proposed network is more consistent with human opinion, which shows the effectiveness of the proposed structure design. table . performance comparison of different methods by – % splitting. methods pc↑ mae↓ rmse↓ square deviation↓ lr [ ] . . ± . . . gr [ ] . . ± . . . svr [ ] . . ± . . . alexnet [ ] . . ± . . . resnet- [ ] . . ± . . . resnext- [ ] . . ± . . . ours . . ± . . . to further testify the network capacity, we perform the comparison via -fold cross validation, which holds – % splitting for each fold. the results and average for each fold are shown in table . from the table, our performance is better than state-of-the-arts. table . performance comparison of the cross validation. pc↑ avg alexnet [ ] . . . . . . r cnn [ ] . . . . . . resnet [ ] . . . . . . resnext [ ] . . . . . . ours . . . . . . mae↓ avg alexnet [ ] . . . . . . r cnn [ ] . . . . . . resnet [ ] . . . . . . resnext [ ] . . . . . . ours . . . . . . rmse↓ avg alexnet [ ] . . . . . . r cnn [ ] . . . . . . resnet [ ] . . . . . . resnext [ ] . . . . . . ours . . . . . . square deviation↓ avg alexnet [ ] . . . . . . resnet [ ] . . . . . . resnext [ ] . . . . . . ours . . . . . . information , , of furthermore, we analyze the distribution of predicted scores from our network, which is shown in figure . the yellow points are frequencies of prediction, while the blue points denotes the ground-truth. from the visualization illustrations, the score of male and female are in accordance with the normal distribution. there is a shift on mean value of male and female predictions. we hold the notion that the shift is from the bias of sexuality. to prove the hypothesis that our prediction accords with the normal distribution, we use the anderson-darling test for evaluation. it is a modification of the kolmogorov-smirnov (k-s) test and gives more weight to the tails than does the k-s test. we make the hypothesis h : samples follow the normal distribution; and the h : samples do not follow the normal distribution. after the a-d test, we get the significance level α = . and the critical value ca−d = . . since α ≤ ca−d , we cannot reject the hypothesis h . from this point of view, we hold the notion that the prediction values follow the normal distribution. (a) male (b) female figure . visualization of prediction distribution. the blue points are the ranks of ground-truth. the yellow points are the ranks of prediction. the x-axis denotes the rank, and y-axis is the frequency. . . ablation study investigation on network design. to show the performance of network design, we make the experiments on different settings of block numbers. specifically, km, kg denote the block and module number in rirm and rirg separately. the results are shown in table . from the table, the depth of network is one of the most important factors of network prediction performance. when the km and kg are lower, the pc, mae and rmse will be worse than the longer network. this accords with the intuition that a wider and deeper network has better representation ability and processes features more effectively. specifically, km and kg have a similar influence on the performance. singly adjusting the km and kg has a similar effect on the results. table . ablation on network design. method pc↑ mae↓ rmse↓ km = , kg = . . . km = , kg = . . . km = , kg = . . . km = , kg = . . . investigation on attention mechanism. to show the performance of the proposed sca, we conduct the comparison with and without sca blocks. the results are shown in table . from the table, the attention mechanism leads to a shallow performance improvement due to the restricted parameters. sca considers the channel attention and spatial attention jointly, which finds the correlations from two perspectives for better consideration. information , , of table . ablation on attention mechanism. sca pc↑ mae↓ rmse↓ w . . . w/o . . . . . discussion comparison on resnext- . in this paper, our network achieves a better performance than resnext- . our network holds . m parameters and . gflops. resnext- has . m parameters and . gflops. from the comparison, our network is lighter than resnext- . although our network is much more deeper than other works, the well-designed convolution operation can prevent the plentiful number of parameters and computation complexity. effectiveness of sca. in this paper, we propose an attention mechanism termed as sca. since there is only one convolution layer and some depth-wise convolutions in sca, it is a simple but effective design for finding the inherent correlation of feature maps. there are few parameters in sca with lower computation complexity. from this point of view, it can give a performance boost with a little increase on complexity. from this perspective, sca is an efficient component for performance boost. comparison on effective network architecture designs. recently, there are different effective network architecture designs for feature exploitation, such as resnet and several extensions, densenet, mobilenet series and squeezenet. these works concentrate on different block designs for effective feature exploitation. however, the choreographed works are concentrating on building a deeper or wider structure for better performance, which lack to build a more efficient information transmission pathway. the main difference of different networks is the inside blocks, and almost all the networks are modified based on resnet- or resnet- , which provide a fixed information transmission pathway for fair performance comparison. to address this issue, we introduce the rir structure for better information transmission. furthermore, these lightweight works focus on different blocks, but do not consider the correlations of features. in this paper, the attention mechanism is introduced to find the inherent correlations for better feature representation, which is termed as sca. threats to validity. in this paper, we propose a novel network for the fbp problem. however, the improved performance is limited by the number of parameters. a deeper or wider network will lead to better performance, while it will also produce a high computation complexity. considering the threats to internal validity, the vital important element is the network depth. from the ablation study, with the increase of network depth, the performance will be improved at the same time. there are two aspects about the threats to external validity. on one hand, the labels for training are assessed by some students in a specific society, which may cannot cover a common opinion. on the other hand, the trained images are selected from asian and caucasian people, which may lead to a bias on the diversity. . conclusions in this paper, we proposed a novel network for the facial beauty prediction problem. traditional networks focus on the effective block designs with a deeper or wider network for better performance, which almost neglect the efficient information transmission pathway and the correlations of features. to address these issues, we proposed a three-level residual-in-residual structure, termed rirg, for better information transmission. since rirg was designed in a recursive way for multi-level residual connections, it could provide a more efficient information and gradient transmission style. furthermore, a joint spatial and channel attention mechanism—sca—was introduced in this paper for finding the inherent correlations of features, which is a tiny component with few parameters for performance improvement. the experimental results showed that our proposed network achieved a better performance than other works with restricted parameters. further, we will find more datasets information , , of with higher diversity, and compare our works with more recent works. meanwhile, we will also tend to build a novel dataset for the fbp problem with more cultures, mentalities, traditions and economic status. author contributions: methodology, k.c.; software, k.-n.c.; writing—original draft, h.j.; writing—review & editing, l.d. all authors have read and agreed to the published version of the manuscript. funding: this work is supported by the science foundation of shenyang university of chemical technology under grant 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[crossref] c© by the authors. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /). http://dx.doi.org/ . /info http://dx.doi.org/ . /info http://dx.doi.org/ . /info http://dx.doi.org/ . /taffc. . http://creativecommons.org/ http://creativecommons.org/licenses/by/ . /. introduction related works facial beauty prediction convolutional neural networks method residual-in-residual group spatial-wise and channel-wise attention network design experiment results ablation study discussion conclusions references chinese facial beauty preference letter to the editor chinese facial beauty preference xingchen zhu • xiao long received: september / accepted: september / published online: october � the author(s) level of evidence v this journal requires that authors assign a level of evidence to each article. for a full description of these evidence-based medicine ratings, please refer to the table of contents or the online instructions to authors www.springer.com/ . dear sir, with great interest, we read the article ‘ideals of facial beauty amongst the chinese population: results from a large national survey’ written by dr. souphiyeh sami- zadeh and prof. woffles wu [ ]. in the paper, the authors investigate ‘the preference of han chinese laypersons for facial shape, profile (straight, convex, concave), jaw angle and shape, and shape of the chin, nose, and lips’ [ ]. from this survey, the authors concluded that the han chinese population prefers an oval facial shape with minor varia- tions to the oval facial shape, a pointed, narrow chin, obtuse mandibular angle for women and a straight facial profile and to some extent an anteriorly projecting chin, a concave or straight dorsum of the nose and small, full lips with well-defined cupid’s bows with tapering volume towards the oral commissures. recently, we have carried out a similar investigation to gain the chinese aesthetic preference for the angles and proportions of midface through three-dimensional facial images processed by photoshop cs . we took a three- dimensional facial image of a -year-old chinese woman, who had no plastic surgery history and no facial deformity. midface angles and proportions including nasofrontal angle, nasolabial angle, intercanthal width/nose width and ocular width/mouse width were modified to various values by photoshop cs [ ]. a total of chinese raters (including plastic surgery patients and people with no plastic history) were recruited to offer their own demographic information such as gender, age, educational fig. investigation picture of different intercanthal widths & xiao long pumclongxiao@ .com; pumclongxiao@gmail.com communication university of china, beijing, china division of plastic surgery, peking union medical college hospital, chinese academy of medical sciences and peking union medical college, no. shuaifuyuan, wangfujing, dongcheng district, beijing , china aesth plast surg ( ) : – https://doi.org/ . /s - - - http://orcid.org/ - - - http://www.springer.com/ http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf https://doi.org/ . /s - - - background, economic condition and plastic history, and to choose the most ideal angle or proportion. in the prelimi- nary results, we found the chinese ideal nasofrontal angle, nasolabial angle, intercanthal width/nose width and ocular width/mouth width were . � ± . �, . � ± . �, . ± . and . ± . . women in north china preferred a larger nasolabial angle, smaller nasofrontal angle and larger ocular width/mouth width than those in south china. elderly chinese with low education levels, high income and high expense had an obvious preference for a small intercanthal width/nose width. we think our investigation results could be the supple- ment data for the samizadeh and wu study. by combining the methods and the results, plastic surgeons from different areas of asia could have a more thorough picture of chi- nese beauty and the chinese aesthetic characteristics could be concluded as well (fig. ). acknowledgements the study was funded by research training project of communication university of china ‘‘the aesthetic evolution of han women in northern china from the perspective of dna genetics’’ grant no. cuc b . compliance with ethical standards conflict of interest the authors declare that they have no conflicts of interest to disclose. open access this article is distributed under the terms of the creative commons attribution . international license (http:// creativecommons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. references . samizadeh s, wu w ( ) ideals of facial beauty amongst the chinese population: results from a large national survey. aesthetic plast surg. https://doi.org/ . /s - - - . othman sa, majawit lp, wan hassan wn et al ( ) anthropometric study of three-dimensional facial morphology in malay adults. plos one :e aesth plast surg ( ) : – http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / https://doi.org/ . /s - - - chinese facial beauty preference acknowledgements references diffractive beauty production at the lhc collider september ocr output geneva, switzerland beauty acceptance and the reconstruction in forward spectrometers. closer the excited proton direction. this may offer some advantages for the pomeron hemisphere opposite to the underlying event which follows triggering on large diffractive masses the beauty system is boosted into the topology for the beauty particles and the underlying event are given. when cross-sections for beauty production at different diffractive masses and the collisions at the lhc we discuss the beauty production in those events. the using the framework of pomeron exchange to describe diffractive pp ahsgact k. eggert and a. morsch diffractive beauty production at the lhc collider xu, ) o cern-at— - - cern at/ <¤¤llllllllllllllllllllllllllllllllllllillll cern libraries, geneva european organization for nuclear research the presence of a pseudorapidity gap, a method frequently used in the past. ocr output proton momentum losses, which cannot be directly detected, can thus be identified by the hemisphere opposite to the pomeron. low mass diffraction (m < . tev) with masses are sketched. the lower the mass the more forward the particles are emitted into in fig. lc, the pseudo rapidity distributions of particles from two different excited favourable in these events. kinematics and the signal-to-background ratio for beauty particles may be more different from the one of normal pp events. it is therefore not excluded that the diffractive events with most of the particles going along the diffractive system is quite diffractive events would lead to a substantial heavy flavour production. the topology of therefore an interesting question to ask whether the possibly enhanced gluon flux in heavy flavours, like beauty and top, are mainly produced by gluon interactions. it is interacts with the proton constituents. function seems to be rather hard [ ]. thus the hard gluon beam from the pomeron the pomeron is seen as a multi-gluon state. measurements indicate that its structure way a pomeron beam can be defined with momenta between and gev. often of · to ‘ by means of roman pots placed upstream in the straight section. in such a as described in ref. [ ], the proton momentum loss écan be measured in the range proton in diffractive events at the lhc is therefore in the range of lo‘to ‘ mass corresponds to the production of one additional pion. the momentum loss of the momentum of above tev is limited by the coherence condition, whereas the lowest the largest momentum loss leading to an excited mass of around tev or a pomeron ( )<; · x = = relative momentum loss §= ap/po by x= -q. the mass m of the system x in which the other proton is excited is related to this fraction of the proton momentum leaving a proton with a beam momentum fraction mass m recoiling against the intact proton (fig. a,b). the pomeron has taken the of one proton, interacts with the other proton and thus produces an excited system with currently believed that single diffraction is mediated by a pomeron which, being a part momentum have been studied at the isr and the proton-antiproton collider . it is[ ][ ] inelastic diffractive processes in which one of the two protons stay intact but looses ocr output . introduction - . ( ) ocr output-- = fs;/p(xi’q )fzi/p(xi’q )`e% dodo*(pip —> qqx functions and the parton-parton cross section. the hard scattering cross-section is a product of the proton and pomeron structure ( )__ €¤\lx sd(.§m <§< gm) - . mb ln pomeron momentum range §mm<§<§max integrating over t and § one obtains for the total diffractive cross section in the diffractive c ·oss section of mb/ side. the normalisation constant c was set to . mb gev‘ corresponding to a total single and u= . , b=o. gev?. o’(pip —-> x) = . mb is the total pomeron proton cross section. ·th “" m ‘ - at p = . .... .._. m m, —t ( -t zi) ( ),f = ——-lt-; = - ;- ·— f f fp/pg ) o·(pip —>x) d§dt o·(pip —+x) gl ( do c dependence of the proton form factor f (t) and an l/{dependence: as described in ref. [ ], the pomeron flux factor was calculated from the t by the pomeron and t symbolises an independent set of mandelstam variables. momentum fraction of the pomeron; t is the transverse momentum squared transferred here, xi and xi denote the momentum fractions of the interacting partons and the differential cross section of the hard scattering between the pomeron and the proton. the first term on the right side is the pomeron flux factor and the second one the j =f ( t) agatdxaxai “°’p ’ ax.ax.ae ( ) d¤(p ¤ -> qqxd¤(pp —> qijx) the differential cross section for pp diffractive hard scattering is: by g. ingelrnan etal. [ ] py'l'l—ha . [ ] in combination with pompyt, a special diffractive event generator built to simulate heavy flavour production in single diffractive pp interactions we used . simulation of diffractive hard scattering - ocr output the ones in the proton and hence the beauty particles are boosted along the pomeron momentum ( - %) the gluons in the pomeron have, on average, larger momenta than direction (fig. ). when the pomeron takes a substantial fraction of the proton the beauty particles move into the opposite hemisphere, following the pomeron hemisphere. with increasing diffractive masses the particle distribution gets wider and particles and the underlying event particles go together into the excited proton the hard structure fimction, in particular at large masses. at low masses the beauty particles follow the underlying diffractive event the distributions are quite different for negative ones of the pomeron. whereas for the soft structure function the beauty functions. positive pseudorapidities denote the hemisphere of the excited proton, the underlying event are shown in fig. for (a) the hard and (b) the soft gluon structure event. the average pseudorapidity and the -range for beauty and the particles from the following figures illustrate the beauty kinematics with respect to the underlying . topology of diffractive beauty events these events. compared to normal pp events. we therefore study in the next chapter the topology of pomeron, have a topology which allows an easier distinction of the beauty particles whether diffractive events with an excited mass around tev, emitted opposite to the the one in normal events, but at the larger energy of tev. it has now to be seen and charm content in diffractive events with a sub energy of ~ tev is comparable to in our assumed scenario, in which the pomeron consist of hard gluons, the beauty normal pp collisions (w/s=l tev), whereas it is above at low diffractive masses (fig. masses. the charm-to-beauty ratio approaches at large masses - , also similar to function of the pomeron this beauty fraction would even exceed % at the highest times larger than in an lhc fixed target scenario. with the soft gluon structure fraction of . % which is similar to pp collisions at w/s= tev and more than a factor magnitude over the mass range (fig. b), reaching at the highest masses a beauty bins of log§. on the contrary, the beauty cross-section increases by two orders of having in mind that the diffractive cross-section is constant (~ . mb! decade) in equal diffractive mass m and for beauty production in this mass bin is plotted versus logl; ln fig. a, the differential cross-sections do/dm for the inclusive production of the . diffractive heavy flavour cross-sections (soft gluons)zfm, (z) = ( - z) ( ) (hard gluons)zfg,,(z) = z( — z) schlein [ ] was used for the calculations and a soft structure function for comparison: is still an open question. the 'hard‘ structure function advocated by ingelman and we assume that the dominant structure of the pomeron consists of gluons, although this - ocr output over a probably much reduced background from the underlying event. energy of about tev thus providing very high momentum gluon·gluon interactions pp collider could thus be transformed into a pomeron-pomeron collider with a sub with roman pot spectrometers double pomeron exchange reactions can be studied. the perform detailed studies of the pomeron structure. by equipping both forward arms study the nature of diffraction and, if the pomeron would be a quasireal particle, to in any case, beauty production in diffractive events would serve as an ideal tool to events. further studied whether such a beauty sample would be cleaner compared to normal acceptance of a forward spectrometer, like e.g. the cobex spectrometer. it has to be mass already on the . level trigger, the beauty particles can be boosted into the pot spectrometers. by choosing the proton momentum loss and hence the diffractive loss of the protons can be measured in the range of ‘to with the help of roman ` signal-to-background ratio is more favourable in these events. the relative momentum (in the case of a hard structure function and large masses), the kinematics and the lower. it may be that, with most of the particles going opposite to the beauty particles collisions at *}s= tev, despite the fact that the sub energy in diffractive events is the beauty production in high mass diffractive events is as large as in normal pp . summary tev. for three mass bins. the beauty momenta are lowest for diffractive masses around distributions of the underlying event particles and the beauty particles are shown in fig. ( m > tev ) and increases above gev at masses below . tev. the momentum the average beauty momentum , shown in fig. , is around gev for large masses beauty production for masses below . tev. mrad. in the proton hemisphere, cobex would almost fully cover the diffractive pairs in high mass diffraction with most of the beauty particles being even within detector (ref. [ ]), placed in the pomeron hemisphere, accepts more than % of the bb assumed spectrometer apertures. as an example, the forward ( mrad) cobex fig. shows the acceptance of the bb pairs as a function of log§ for different combinatorial background for beauty reconstruction. most of the underlying event particles are in the proton hemisphere thus reducing the over only a few units can be boosted into the acceptance of the apparatus. secondly, large diffractive mass the beauty particles with a pseudorapidity distribution extending direction. from the experimental point of view this has two advantages: by choosing a [ ] cobex letter of intent, cern/lhcc/ - . ocr output [ ] a. donnachie and p.v. landshoff, nucl. phys. b ( ) . diffractive hard scattering processes', desy . [ p. bruni and g. ingelman, 'pompyt version . - a monte carlo to simulate t. sjostrand, comp. phys. comm. ( ) , ibid. ( ) . [ ] h.-u. bengtsson, t. sjostrand, comp. phys. comm. ( ) . [ ] g. ingelman and p. schlein, phys. lett. b ( ) . lhc low-/ insertion', cern at/ - (di). [ ] k. eggert and a. morsch, 'leading proton detection in difractive events for an [ ] m. bozzo et al., phys. lett. b ( ) . [ ] m.g. albrow et ul., nucl. phys. b ( ) . references - ocr output tev and (c) m = . tev. the recoil protons show up at the right-hand side of the plots. assuming a hard gluon structure function for (a) diffractive mass m= . tev, (b) m= . particle rate per event vs. momentum for underlying event and beauty particles fig. (b) soft gluon structure function. average momentum of the beauty particles vs. l g(€) for (a) hard gluon structure and fig. rnrad (dashed line) and mrad (dotted line) aperture. beauty-antibeauty pair acceptance for forward spectrometers with mrad (solid line), fig. the plots. (b) m= . tev and (c) m= . tev. the recoil protons show up at the right-hand side of particles assuming a hard gluon structure function for (a) diffractive mass m= . tev, particle density distribution vs. pseudo rapidity for underlying event and beauty fig. particle distribution. lines show the range of coverage of the underlying event and the width of the beauty (line) for (a) hard gluon structure and (b) soft gluon structure function. the vertical the average pseudo rapidity for beauty particles (points) and underlying event particles fig. ratio of ce to bb cross-section. fig. (b) ratio of bil to total diffractive cross-section. (dotted curve) assuming a hard gluon structure function of the pomeron. (a) total diffractive cross—section vs. log(§) (solid curve) and diffractive bb cross-section fig. (c) sketch of the single—diffractive event topology for two different diffractive masses m. (b) single diffractive reaction represented by a t-channel pomeron exchange diagram. diffractive reaction p+p—> p+x. (a) the initial state momentum vectors in the , overall centre—of-mass of the single fig. figure captions wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ | e. richardson et al. molecular biology of the cell evolutionary cell biology: functional insight from “endless forms most beautiful” elisabeth richardsona, kelly zerra, anastasios tsaousisb, richard g. dorrellc, and joel b. dacksa adepartment of cell biology, university of alberta, edmonton, ab t g h canada; blaboratory of molecular and evolutionary parasitology, school of biosciences, university of kent, canterbury ct nj, uk; cschool of biology, École normale supérieure, paris , france abstract in animal and fungal model organisms, the complexities of cell biology have been analyzed in exquisite detail and much is known about how these organisms function at the cellular level. however, the model organisms cell biologists generally use include only a tiny fraction of the true diversity of eukaryotic cellular forms. the divergent cellular processes observed in these more distant lineages are still largely unknown in the general scientific com- munity. despite the relative obscurity of these organisms, comparative studies of them across eukaryotic diversity have had profound implications for our understanding of fundamental cell biology in all species and have revealed the evolution and origins of previously observed cellular processes. in this perspective, we will discuss the complexity of cell biology found across the eukaryotic tree, and three specific examples of where studies of divergent cell biol- ogy have altered our understanding of key functional aspects of mitochondria, plastids, and membrane trafficking. the field of cell biology has made tremendous strides in understand- ing eukaryotic cells, especially animals and yeast. concurrently, evo- lutionary biology has opened up a window to the origins of our spe- cies and the genes that define us. though these fields have intersected conceptually for decades, a recent movement is explicitly uniting these two fields into the discipline of evolutionary cell biology with great success (brodsky et al., ; lynch et al., ) and, we argue here, potentially an even greater future. one drive behind this movement is to harness the comparative approach of evolutionary biology and apply it to questions of cellular origins and cellular func- tion. this approach has yielded beautiful insight into animal cellular function from mitotic spindle dynamics (helmke and heald, ) to glycosylation machinery (varki, ). however, expanding the scope of investigation to organisms beyond fungi and animals to span eu- karyotic diversity has allowed for discoveries that force us to adjust some fundamental ideas of how eukaryotic organelles work, and why. monitoring editor david g. drubin university of california, berkeley received: may , revised: aug , accepted: aug , doi: . /mbc.e - - address correspondence to: joel b. dacks (dacks@ualberta.ca). © richardson et al. this article is distributed by the american society for cell biology under license from the author(s). two months after publication it is avail- able to the public under an attribution–noncommercial–share alike . unported creative commons license (http://creativecommons.org/licenses/by-nc-sa/ . ). “ascb®,” “the american society for cell biology®,” and “molecular biology of the cell®” are registered trademarks of the american society for cell biology. abbreviations used: ap, adaptor protein; cia, cytosolic iron–sulfur assembly; leca, last common eukaryotic; ancestor; mros, mitochondria-related organ- elles; nif, nitrogen fixation; suf, sulfur utilization factor. mboc | perspective eukaryotic diversity: from animacules to amitochondriates from van leeuwenhoek’s description of his “animacules” soon after the development of the microscope, cell biology has always been linked with single-celled organisms. nonetheless, studies of cell bi- ology and physiology remain restricted to relatively few model or- ganisms, such as flies, worms, yeasts, and human cells, often closely related to humans and manipulated under restrictive circumstances (del campo et al., ). this means that pathways and mechanisms assumed to be essential from their presence in conventional model organisms may actually be divergent or lineage specific, and this can lead to unjustified extrapolation of cell biological principles be- yond their actual range. conversely, because our knowledge is so heavily based on taxonomically restricted model systems, we may be missing key cell biological components, pathways, or phenom- ena in cells beyond humans and yeast, or overlooking potentially important aspects of our own cellular biology. reaping the benefit of the vast amounts of genomic data now available from diverse organisms, evolutionary biologists have per- formed large-scale molecular evolutionary analyses. together with morphological information from light and electron microscopy, this molecular information has been used to establish the eukaryotic tree outlined in figure and to formalize a coherent framework for eukaryotic relationships (adl et al., ). most model cell biological systems (flies, worms, yeast and hu- man cells) are grouped within the supergroup opisthokonta (figure ). however, this only scratches the surface of eukaryotic volume december , evolutionary cell biology | cultivated and edible seaweed species (e.g., nori), and glauco- phyte algae. stramenopiles, alveolates, and rhizarians are grouped within the sar supergroup, related to archaeplastids (figure ). the sar supergroup contains many parasitic species, including the malaria-causing plasmodium falciparum, as well as diatoms and dinoflagellates that play an absolutely vital role in nutrient cy- cling in aquatic ecosystems. the final two eukaryotic supergroups are less securely placed. the controversial ccth supergroup is thought to be most closely related to the sar and archaeplastid supergroups and tentatively contains algae such as the crypto- phytes and haptophytes. the latter can grow in blooms large and dense enough to be visible from space. the ccth supergroup may contain lesser-known marine organisms such as the centrohe- lids and telomerids, but our understanding of the relationships between these four lineages is in relative flux. the last supergroup, diversity. while the taxonomy may be daunting, the organisms classified outside opisthokonta have tremendous medical impor- tance (including parasites of global health relevance), agricultural relevance (both plants and their pathogens), and ecological impli- cations (key players in all known food webs). understanding eu- karyotic diversity is to understand critical aspects of the world in which we live. the opisthokonts are related to two lineages of single-celled flagellates, apusozoa and breviates (brown et al., ), and the amoebozoans, a group containing ecologically rel- evant soil microbes and pathogenic organisms (e.g., entamoeba histolytica, the causative agent of amebic dysentery, and dictyo- stelium, an emerging cell biological model organism and an im- portant constituent of forest ecosystems). archaeplastids (figure ) encompass multicellular plants and green algae within the viridi- plantae, but also the red algae (rhodophytes), which include many figure : diversity of aspects of cell biology across eukaryotes. phylogenetic relationships of major eukaryotic lineages, with emphasis on lineages highlighted by cell biological examples. the rooting is shown within the supergroup excavata, with discobans on one side and malawimonads and collodictyon on the other. the relationships shown are based on information from adl et al. ( ), brown et al. ( ), and derelle et al. ( ). the table illustrates the diversity of the cell processes discussed in this review. column (mitochondria): type of mitochondria present in the lineage. mito, conventional mitochondria; m/h, a mitochondria/hydrogenosome-like organelle; h, a hydrogenosome; m, a mitosome. column (fe/s system): fe/s production system present in the cell and its localization. isc, a conventional iron/sulfur cluster pathway; cpsuf, a suf system localized in the chloroplast; csuf, a suf system localized in the cytosol; c, m nif, a nif system localized to the chloroplast and mitosome; and c, m suf, a suf system localized to the cytosol and mitosome. column (history): number of endosymbiotic events involved in establishment of plastids in the lineage; chromalveolate plastids, where the exact phylogenetic derivation is currently unknown, have been indicated with a “c.” column (pigment): presence or absence of a plastid and, if present, evolutionary affinity of the plastid. red denotes plastids of red algal origin; green denotes plastids of green algal origin; teal indicates plastids that are ancestral to the red and green lineages; purple indicates that this is a plastid of red algal origin, but is no longer photosynthetic. multiple colors indicate the presence of multiple plastid types within the taxonomic group. column (ap- ): complete presence, partial presence, or absence of ap- , respectively represented by fully colored, half-colored, or white. gray indicates taxa not searched for ap- . column (tset): complete presence, partial presence, or absence of tset, respectively represented by fully colored, half-colored, or white. gray indicates taxa not searched for tset. photosynthetic stramenopiles blastocystis discoba metamonads collodictyon malawimonads archamoebae amoebozoa apusozoa animals basidomycetes ascomycetes breviates apicomplexans rhizarians ciliates microsporidia glaucophytes rhodophytes viridiplantae haptophytes cryptophytes mito m/h mito, h, m/h mito mito, m mito, m mito h, m mito h, m mito mito mito mito mito mito mito mito, m mito mito mito mito cpsuf isc c, m nif c, m suf isc/cpsuf isc isc isc isc isc isc isc isc isc isc isc isc isc isc isc/cpsuf isc/cpsuf isc/cpsuf isc/cpsuf isc/cpsuf c, , c c c c archaeplastida ccth sar excavata amoebozoa apusozoa opisthokonta organelle fe/s system ap- tset mitochondria history pigment plastid membrane-tra�cking mito mito | e. richardson et al. molecular biology of the cell investigated eukaryotes appear to contain mros raises questions about the “essential” function of the organelle; if not energy gen- eration, then what? proteomic analyses of mitochondria and mros (sickmann et al., ; heazlewood et al., ; smith et al., ; jedelský et al., ) have demonstrated that formation and export of iron–sulfur (fe-s) clusters, essential for several enzymatic catalyses and regula- tion of gene expression, are the only universally conserved biosyn- thetic pathway localized within these organelles (hjort et al., ). although iron and sulfur can be assembled in nature, the individual components are toxic for the cell itself. in typical eukaryotes, the mitochondrial iron–sulfur cluster (isc) biosynthetic machinery is responsible for the assembly of fe-s clusters in the mitochondria and supports the cytosolic iron–sulfur assembly (cia) machinery (figure ai), for the assembly of the cytosolic and nuclear fe-s clus- ters. it is now widely accepted that the isc could be the raison d’etre of these organelles (lill et al., ). in microbial eukaryotes, the story is more complicated. despite the presence of isc machinery and export in all mitochondria and most mros, including remnant organelles (goldberg et al., ), new fe-s cluster biosynthetic machineries have recently been de- scribed in microbial eukaryotes. blastocystis, an anaerobic member of the sar supergroup (figure ), encodes a fused version of the components of the sulfur utilization factor (suf) system (figure aii; tsaousis et al., ). this system, which is also involved in fe-s cluster formation but is evolutionarily unrelated to the isc machin- ery, is typically found in bacteria, methanoarchaea, and plastid-bear- ing organisms. the suf machinery localizes in the cytosol of blasto- cystis and is induced under oxygen stress conditions (tsaousis et al., ), potentially affecting the cia machinery protein composition and function (tsaousis et al., ). a similar acquired system was also found in the free-living breviate pygsuia biforma (figure ), but here the suf machinery is also mitochondrially localized (stairs et al., ; figure aiii) and the isc machinery appears to be absent. finally, in the amoebozoans (figure ) entamoeba and mastig- amoeba, the isc system is also nonexistent; instead a nitrogen fixa- tion (nif)-related system from epsilon-proteobacteria is localized both to the mros and the cytosol (figure a, iv and v; maralikova et al., ; nývltová et al., ). this calls into question the pur- pose of the isc and cia pathways in the origin and existence of ancestral mitochondria. the reasons for modifications are undeter- mined, but alternations in environmental oxygen levels could have played a fundamental role in their acquisition, selection, and retention. although energy production is presently accepted as the driver for the origin of mitochondria (lane and martin, , but see gray, , for an intriguing alternative), it appears to be fe-s cluster as- sembly that is the organelle’s conserved essential function (lill et al., ; embley and martin, ). still, with – % of proteins be- ing of unknown function in all mros studied to date (sickmann et al., ; heazlewood et al., ; smith et al., ; jedelský et al., ; schneider et al., ), investigating the “unknown functions” of mitochondria and mros could yet provide us with some unexpected answers to understanding the origins and cellular role of this organelle. plastid acquisition: complex endosymbiotic history shapes physiology the other well-known endosymbiotic organelles are the chloro- plasts or, more generically, plastids. best known for their role as the site of photosynthesis in eukaryotes, they can carry out a number of excavata, includes important parasites, such as the diarrheal agent giardia and the agent of african sleeping sickness, trypanosoma brucei. function and diversity: how one informs the other the question of which eukaryotic lineage is the most ancient (i.e., where the root of the tree of eukaryotes is placed) has important implications for how one interprets cell biological data between or- ganisms and across evolutionary time. cell biological traits ob- served in the various eukaryotic supergroups are most logically in- terpreted with the starting state being at the root and change inferred from there. the latest and most robust molecular evolution- ary analyses place excavata straddling the root of eukaryotes (figure ), which would place an ancient divide between its mem- bers (derelle et al., ). this rooting implies that the last common eukaryotic ancestor (leca) had a complex set of cytoskeletal ar- rangements and was likely biflagellated (yubuki and leander, ; derelle et al., ), as this is the cell biology we observe across eukaryotes, even in lineages that diverged extremely early in evolu- tionary history. comparative molecular evolutionary studies also re- construct a leca that is anything but simple or primitive. analyses of proteins associated with nuclear function, membrane trafficking, metabolism, and more have reconstructed a sophisticated comple- ment of machinery present in the leca (koumandou et al., ), estimated to have been in existence ∼ . billion years ago (eme et al., ). delving into this complexity, particularly in organisms for which genomic information can be combined with molecular cell biologi- cal analyses, has provided surprising findings about the biology and function of modern cells. we highlight three examples below, show- ing the different ways in which an evolutionary cell biological ap- proach can be fruitful. in the first two examples, organisms with di- vergent organelles were studied in order to better understand the evolution and diversity of organellar function. in the last case, purely exploratory studies of genomic and cell biological diversity revealed unforeseen cellular components and pathways. mitochondria: highly retained, but why? best known as the powerhouse of the cell, due to its involvement in aerobic respiration and energy generation, mitochondria were among the first organelles to capture the attention and inspiration of evolutionary cell biologists. evolutionary analysis was key to the startling discovery in the s that these organelles derived from an endosymbiotic alpha-proteobacterium and the further revela- tion (muller et al., , among others) that the diverse double membrane–bound organelles in disparately related anaerobic eu- karyotes are, in fact, derived mitochondria. hydrogen-producing organelles (i.e., “hydrogenosomes”) are found in ciliates, members of the sar supergroup, and in several members of the excavata group, including trichomonas (figure ). the even more reduced mitochondria, so-called mitosomes, are found in diverse groups, including the metamonad giardia, the amoebozoan entamoeba, the apicomplexan cryptosporidium, and the opisthokont micro- sporidia (figure ). these mitochondria-related organelles (here- after collectively called mros) can be found in at least one taxon in almost all eukaryotic supergroups (figure ) and may harbor no more than proteins (jedelský et al., ) out of that are usually found in canonical mitochondria. contrary to the well- known role of mitochondria, some mros are not involved in energy generation at all; some may “steal” atp from the organism’s cyto- sol in order to function (tsaousis et al., ). that all currently volume december , evolutionary cell biology | other functions, including synthesis of cofactors (fe-s clusters), fatty acids, and heme (dorrell and howe, ). the evolutionary history of a given plastid provides context for its cell biology, and thus the function of a key organelle in a dazzling array of ecologically and agriculturally important eukaryotes. plastids initially arose from the endosymbiosis (figure bi) of a cyanobacterium by the common, heterotrophic ancestor of the archaeplastids (green algae, red al- gae, and plants), but their presence is not limited to this supergroup (walker et al., ). members of the green and red algae were subsequently taken up and converted to organelles through higher- order endosymbioses (figure bii) by at least seven other eukaryotic lineages distributed across multiple supergroups (figure ). endosymbiosis was initially considered rare, due to it being “mu- tationally onerous” (cavalier-smith, ), and early evolutionary models accordingly minimized plastid acquisition. the chromalveo- late hypothesis (cavalier-smith, ) explained the distribution of plastids by parsimoniously suggesting that the plastids of several ecologically important algal groups (cryptophytes, haptophytes, stramenopiles, and dinoflagellates) originated through a single, sec- ondary endosymbiosis of a red alga. the use of chlorophyll c as a light-harvesting pigment suggests their common origin, as do plas- tid gene phylogenies that consistently recover monophyletic rela- tionships between these chloroplast lineages (bachvaroff et al., ). however, evidence has come to light in the last decade that the story may be more complex than it first appeared. multigene phylogenies of nuclear genes have conclusively shown that each of the putative chromalveolate lineages are more closely related to nonphotosynthetic eukaryotes than they are to each other. for example, the stramenopiles and dinoflagellates are very closely related to the rhizarians, a group composed almost en- tirely of nonphotosynthetic protists (burki et al., ). multiple, independently conducted studies of nuclear and mitochondrial ge- nomes have now rejected the monophyly of the putative “chromalveolate” lineages (baurain et al., ; burki et al., ; stiller et al., ). some authors argue for a single ancestral acqui- sition in the common ancestor of chromalveolate and related lin- eages, with extensive loss (cavalier-smith, ). nonetheless, the monophyletic nature of chromalveolate plas- tids but disparate evolutionary origins of the corresponding nuclear lineages suggest a complex progression of endosymbiosis. recent studies have found evidence for multiple endosymbiotic transfers figure : illustrations of cell biological complexity. (a) diagram demonstrating the alternative pathways of biosynthesis of fe-s clusters in microbial eukaryotes. (i) a typical eukaryotic cell requires the isc system to support the mitochondrial apo-(fe-s)-proteins (proteins that require fe-s clusters to be functionally active) and the cia machinery for the cytosolic and nuclear apoproteins. (ii) blastocystis requires a modified cia machinery and the suf machinery for the maturation of its cytosolic, nuclear, and oxygen- sensitive apoproteins. (iii) pygsuia has the suf machinery localized in its mitochondria instead of the typical isc machinery for the support of the organellar apoproteins. (iv) entamoeba has lost the traditional isc machinery and has acquired nif machinery in its cytosol for the support of their apoproteins. (v) mastigamoeba has lost the traditional isc machinery and has acquired two nif machineries in its cytosol and its hydrogenosome for the support of their apoproteins. (b) diagram demonstrating various methods of plastid acquisition found in various lineages. (i) primary endosymbiosis, in which a cyanobacteria is engulfed by a heterotrophic eukaryote, resulting in establishment of chloroplasts. (ii) secondary endosymbiosis, in which a photosynthetic eukaryote is engulfed by a heterotrophic eukaryote, resulting in establishment of chloroplasts. other cell structures from the original eukaryote may also remain. (iii) tertiary endosymbiosis, in isc isc cia cia cia cia nif nif suf typical eukaryotic cell blastocystis (stramenopiles) pygsuia (breviates) entamoeba (amoebozoa) mastigamoeba (amoebozoa) : fe/s clusters nu nu nu nu * * * a ii. . v. v. suf ? ? cia nifnu * ?suf i. b t ap- nucleus golgi lysosomes late endosome early endosome recycling endosome tset plasma membrane ii.i. iv. c primary endosymbiosis secondary endosymbiosis serial endosymbiosis iii. tertiary endosymbiosis which a photosynthetic organism containing a secondary plastid is itself engulfed by another eukaryote, to produce a plastid. (iv) serial endosymbiosis, in which a photosynthetic eukaryote is engulfed by another photosynthetic eukaryote. this results in the establishment of a replacement chloroplast of a different phylogenetic derivation. (c) diagram of a eukaryotic membrane-trafficking system. major endomembrane organelles are labeled; trafficking pathways are denoted by curved arrows. localization and structure of tset and ap- indicated by blue and magenta structures, respectively. all adaptin complexes and tset and copii share a heterotetrameric quaternary structure of two large subunits and a medium and a small subunit as illustrated for ap- and tset. the fcho of animals is derived from the tset medium subunit (drawn here as the blue exclamation point–shaped component). the shared quaternary structure and sequence conservation between subunits of the complex is evidence of their being derived from an ancient common ancestor. recent analyses have begun to resolve their interrelationships and, by inference, the evolutionary order of emergence for the pathways in which they act. for more details see hirst et al. ( ). | e. richardson et al. molecular biology of the cell (boehm and bonifacino, ). however, a fifth ap (ap- ) was recently discovered. together with the ancient nature of the other four, this indicates that the leca contained at least five ap com- plexes (hirst et al., ). the twist is that the human genes encoding the subunits of ap- (figure c) were known earlier but went unstudied until ap- homologues were detected in naegleria, a discoban (figure ) of distant relation to humans that was of interest as a key evolutionary sampling point. this hinted at widespread occurrence and presumptive cellular importance, prompting functional investigation. characterization in hela cells showed ap- localized to late endosomes and lysosomes (figure c) with knockdown causing defects in endosomal traf- ficking (hirst et al., ). abnormalities in ap- are consequently associated with human disease, such as hereditary spastic para- plegia (hirst et al., , ). further taxonomic investigation also detected ap- components beyond humans and naegleria, in diverse eukaryotes (figure ) including arabidopsis (viridiplan- tae), entamoeba (amoebozoan), and toxoplasma (apicomplexan), suggesting that ap- is a central component of membrane traf- ficking in eukaryotic cells. following the discovery of ap- was the report of yet another relative of the aps, the heterohexameric tset (figure c). analyses of tset function in arabidopsis and dictyostelium showed tset to be located at the plasma membrane, facilitating cargo transport (gadeyne et al., ; hirst et al., ). similar to ap- , tset was detected across eukaryotic diversity and is thus ancient; by contrast, tset is not as well retained as ap- in animals and fungi (figure ). nevertheless, study of tset revealed the origins of the human fcho protein (gadeyne et al., ; hirst et al., ), which is important in endocytosis regulation. the monomeric fcho ap- pears to be the remnant of the once full tset complex; essentially, fcho is the vestigial c-terminus domain of the tcup subunit, fused with an associated f-bar domain that, in animal cells, had earlier been discovered to be involved in clathrin-mediated endocytosis at the plasma membrane (mcmahon and boucrot, ). the search for distant homologues of known membrane-traffick- ing machinery that are found across the span of eukaryotic diversity did more than identify ancient cellular components. the broad evo- lutionary distribution of ap- and tset components implied some conserved essential function and brought candidate genes to the fore, with the existence of these having since proven to have powerful implications. other such genes exist and await functional characterization, hopefully with benefits for agriculture, ecology, or human health (hirst et al., ). conclusions evolutionary cell biology has provided unique insights into the core function of mitochondria, how history explains physiology of plas- tids, and the identity of novel membrane-trafficking complexes and pathways relevant to human health. key to these findings has been the complementary use of genomic and informatic analyses with molecular cell biological and microscopic data. the emergence of model organisms from outside the animals and fungi has been in- valuable in this regard. dictyostelium (http://dictybase.org) and arabidopsis (www.arabidopsis.org) are particularly well-developed systems; although not mentioned explicitly here, work in the api- complexan toxoplasma gondii (kim and weiss, ) and the exca- vate trypanosoma brucei (barry et al., ) has greatly contributed to comparative cell biological understanding. the development of further genetic databases and tools for manipulating these organ- isms and others across the diversity of eukaryotes will provide ex- perimental data to contextualize fundamental cellular traits and to between different “chromalveolate” lineages. these studies sug- gest that an endosymbiosis of a red alga initially occurred within the cryptophyte algae and that this plastid was then acquired by other lineages (such as dinoflagellates, haptophytes, stramenopiles) through higher-order endosymbioses (tertiary or quaternary; see figure biii; stiller et al., ). there are even more complex endo- symbiotic events known. some dinoflagellates, for example, have lost their original plastids (presumably from red algae) and replaced them with ones derived from other photosynthetic algae (hapto- phytes, stramenopiles, and green algae) in a process termed “serial endosymbiosis” (burki et al., ; figure ). regardless, the emerg- ing story from these and other studies is that plastid endosymbiosis is a much more widespread and complex process than previously thought. resolving the evolutionary histories of plastids informs our mechanistic understanding of algal cell biology, since each time a plastid is acquired through endosymbiosis, both the biology of the plastid and host may change to accommodate one another. pro- teins derived from the host are likely to be retargeted to the plastid, and genes from the plastid may in turn be adapted to support the biology of the host. lineages that have undergone complex and serial endosymbiotic events may therefore be supported by a mo- saic of different biochemical pathways from different evolutionary sources. for example, some dinoflagellates that have undergone serial endosymbiosis retain unusual gene expression pathways as- sociated with their original, red algal plastids (rna editing and ′ tail addition) and now use these pathways in their replacement plastids (dorrell and howe, ). while these diverse algal lineages may be unfamiliar to many cell biologists, they are well-known to oceanog- raphers and public health officials, accounting for half of primary carbon fixation worldwide and, in some cases, producing harmful algal blooms (place et al., ). as climate change modifies our oceans and skies, understanding the cell biology of these chimeric organisms forged through endosymbiosis will be essential for main- taining a healthy global environment. unexpected membrane-trafficking machinery: something old, something new although understanding endosymbiosis has been a key success of evolutionary cell biology in the past + years, some organelles must have been derived from building blocks in the proto-eukary- otes themselves (dacks and field, ). the best candidates are organelles of the membrane-trafficking system. consisting of mem- brane-bound components that include the endoplasmic reticulum, golgi complex, lysosomes, endosomes, and the plasma mem- brane, the membrane-trafficking system is responsible for sub- stance intake, transport within cells, and secretion from them. the system is critical for normal cellular function, and its malfunction in humans can manifest as diseases such as cancer and cardiac dis- ease (aridor and hannan, , ). evolutionary analysis of the membrane-trafficking system has revealed the proteins of mem- brane trafficking (e.g., snares, rabs, coatomers, and adaptor pro- teins [aps]) to be conserved across eukaryotes (koumandou et al., ). this suggested the presence of sophisticated machinery in leca, prompting a proposed mechanism for how organelles might evolve, if not by endosymbiosis (dacks and field, ). this ap- proach to exploring diversity for the sake of evolutionary under- standing has also yielded some surprises about membrane traffick- ing in modern cells. four heterotetrameric ap complexes have been known since to recruit specific cargoes to their corresponding, newly form- ing, vesicles for transport in the post-golgi and endocytic system volume december , evolutionary cell biology | find new features lost or ignored in our more traditional model sys- tems of animals and fungi. the discoveries of new organellar evolu- tion and function gives us a taste of what may be left to uncover by embracing and exploring eukaryotic genomic and cellular diversity. acknowledgments we thank h. goodson, t. simmen, and j. hirst for critical reading of the manuscript. a.t. is supported by a biotechonology and biologi- cal sciences reserach council (bbsrc) research grant: bb/ m / . r.g.d. is supported by a postdoctoral research fellow- ship from the mairie de paris. e.r. is supported by a graduate re- cruitment scholarship from the university of alberta faculty of med- icine and dentistry and funds to j.b.d. from alberta innovates technology futures. k.z. is supported by a summer studentship from alberta innovates health solutions, and j.b.d. is the canada re- search chair in evolutionary cell biology. the quotation in the title of this perspective is from charles darwin (the origin of species, ). references adl sm, simpson agb, lane ce, lukeš j, bass d, bowser ss, brown mw, burki f, dunthorn m, hampl v, et al. 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( ). libor as a keynesian beauty contest: a process of endogenous deception alexis stenfors‡ abstract: this paper uses the keynesian beauty contest as a theoretical framework to analyse the london interbank offered rate (libor) fixing mechanism, where the actual money market rate is seen as a fundamental value towards which the libor should aim. by treating the libor as the outcome of a particular kind of p-beauty contest game, in which players (libor banks) are guided by higher order beliefs, a process is created whereby they are not solely dependent on their own incentives and constraints. instead, potential deception is generated endogenously though the fixing process itself, resulting in systematic deviations of the libor from its fundamental value. introduction until around , the london interbank offered rate (libor) was widely perceived to be a reliable reflection of the interbank money market colloquially and professionally in the economic literature. academics treated the terms as if they were synonyms. policy makers acted as if the libor was an objective reflection of the money market rate. corporates and households entered into libor-indexed financial contacts as if the money market was the underlying benchmark. recently, however, claims that the benchmark, at times, has been subject to attempts of manipulation by libor panel banks, have placed this into question. ‡ department of economics and finance, portsmouth business school, university of portsmouth, richmond building, portland street, portsmouth po de, uk. email: alexis.stenfors@port.ac.uk. this article has benefitted greatly from discussions with professor costa lapavitsas (soas, university of london), professor stergios skaperdas (university of california), professor yuval millo (university of leicester), professor yanis varoufakis (university of texas) as well as participants at the libor games seminar, soas, november . an earlier version of this article was made available online in october as rmf discussion paper no. (http://www.researchonmoneyandfinance.org/index.php/publication/discussion-papers). libor-indexed derivatives portfolios and the stigma attached to signalling a relatively high funding cost to the rest of the market appears to have given some banks sufficiently strong incentives to submit ‘deceptive’ libor quotes in order to reap monetary benefits from having the privilege to participate in the libor fixing process (financial services agency, ; financial services authority, ; u.s. commodity futures trading commission, ). the libor fixing mechanism lacks binding rules requiring banks to trade at their submitted quotes, and is in fact not a market per se. instead, the benchmark is determined by a selected group of panel banks as follows. a designated calculation agent (such as reuters) collects submitted quotes from the individual panel banks before noon. the trader or another bank person at the cash desk or treasury submits his or her quote from the bank terminal, and the other banks do the same without being able to see each others’ quotes. the calculation agent audits and checks the quotes for obvious errors and then conducts the ‘trimming’, omitting the highest and lowest quotes (the number of which will depend on the sample size). finally, the arithmetic mean is calculated, rounded to the specified number of decimals and published at a specific time depending on the benchmark (british bankers association, ). the fact that libor panel banks not only have the means and opportunity, but also the incentive, to submit deceptive quotes, is of course not exclusively an issue confined to legal scholars. in theory, the libor should reflect current and expected future policy rates, credit and liquidity risk. the assumption, or rather false perception, that the libor itself is based upon actual market transactions is in fact central to previous attempts to decompose the libor and money market risk premia such as libor-ois spreads (see, for example: bank of england, ; mcandrews, sarkar, & wang, ; poskitt, ; schwartz, ). this approach assumes that the libor rate is objective in the sense that it perfectly reflects where the panel banks are able to raise funds from each other, i.e. the money market rate. problematically, the method is not robust should the libor for one reason or the other not equal this money market rate. moreover, should the by far most frequently used benchmark for the interbank money market be systematically manipulated, it would have far-reaching the libor is used broadly in this article also to capture other libor-equivalent benchmarks with similar fixing mechanisms, such as the euro interbank offered rate (euribor), the norwegian interbank offered rate (nibor), the stockholm interbank offered rate (stibor) and the tokyo interbank offered rate (tibor). ois refers to the overnight index swap consequences for financial markets and policy makers alike. therefore, greater insight into how the libor fixing mechanism works theoretically is essential in political economy. stenfors ( ) adopts a game-theoretical approach to illustrate how the libor fixing, at a given time, can be driven by different incentives and constraints of the individual libor panel banks. by constructing and solving simple ‘libor games’, it is shown that the trimming process associated with the libor fixing mechanism is not effective in ensuring a ‘fair’ libor fixing. an endowment in the form of a libor-indexed derivatives portfolio, or the stigma attached to signalling high funding costs relative to others, can act as incentives to submit libor quotes deviating what could be regarded as the ‘actual’ money market rate. different forms of collusion can be a possible but not exclusive reason for an ‘off-market’ libor rate if panel banks do not know each others’ endowments, but rather assume that all banks always aim to opt for the best possible strategy to use its ability to influence the libor fixing. significantly, constraints put in place to make the mechanism more ‘market- like’ are shown to require full transparency to be effective. this article extends the game-theoretical analysis of the libor fixing mechanism. instead of treating it as a single-period game with equally creditworthy players, it emphasises the fact that libor submissions are made daily and that the perceived creditworthiness of banks might differ. in doing so, it considers whether the deviation between the libor and the rate it fundamentally should reflect can be systematic. this is important as any future modification in the way the benchmark is determined ultimately needs to consider its simple and original purpose: namely to represent the average interbank money market rate. keynesian beauty contests in general, and p-beauty contest games in particular, have often been used to illustrate why stock markets are volatile and how the price of a tradable asset systematically can deviate what objectively could be regarded as its fundamental value. from this perspective, we could also consider if some kind of fundamental value exists in the money market, and if and why the money market rate at times deviates from this value. the libor, in this context, should be seen as a reflection of the money market rate, and not vice versa. using the keynesian beauty contest framework, this article conceptualises the money market as a kind of fundamental value against which the libor should be benchmarked. the libor rate is supposed to be an objective reflection of the interbank money market rate, and more specifically the average subjectively reported funding cost of a group of banks. this reporting mechanism is viewed in terms of a libor game, being played an infinite number of times, and consisting of players guided by the anticipation of what others will do and what they anticipate others will do. by regarding the libor fixing as the outcome of a peculiar form of a p-beauty contest game, a situation is demonstrated where the libor deviates from this money market rate. in fact, a p-beauty contest game is precisely how we could view the libor game. the results presented in this article show that as players are guided by higher order beliefs, some libor panel banks can be seen as being driven towards a behavioural pattern that is not dependent on their own incentives and constraints in the first instance, but generated endogenously though the process itself. deception in this case does not need to result from the self-interest of an individual libor submitter, but rather from the perception that others will act in such a manner that not submitting deceptive libor quotes would be punished. this can result in long-lasting deviations of the libor from the underlying money market. the current libor fixing mechanism can be seen as a facilitator of such behaviour. this article is structured as follows. section provides a brief overview of p-beauty contest games in the literature, and a discussion on how the libor could conceptually fit into this context. in section , a simple libor p-beauty contest game is constructed with the aim of being as realistic as possible. given the utility function of each player (libor panel bank), possible outcomes of this game are then considered in section . section draws conclusions. the p-beauty contest game: regarding the money market as the ‘fundamental value’ professional investment may be likened to those newspaper competitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average preferences of the competitors as a whole: so that each competitor has to pick, not those faces which he himself finds prettiest, but those which he thinks likeliest to catch the fancy of the other competitors, all of whom are looking at the problem from the same point of view. it is not a case of choosing those which, to the best of one’s judgement, are inspiration for the design of the libor game as p-beauty contest game has, in part, been drawn from numerous discussions and interviews with market participants during - . in total, individuals, representing banks and interdealer brokers, either directly or very closely involved in the libor, tibor, nibor and stibor fixing process were consulted. really the prettiest, nor even those which average opinion genuinely thinks the prettiest. we have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. and there are some, i believe, who practise the fourth, fifth and higher degrees. (keynes, : p. ) this passage from keynes has provided the basic platform for numerous and different variants of games labelled as keynesian beauty contest games. in essence, we are in dealing with the phenomenon of market participants not always simply seeking a long-term fundamental value of an asset, but taking a more short-term view and incorporating what s/he believes others will do and how they believe others will do and so on. although some of the games modelled with this passage in mind might lack direct connotations to keynes (fung, ; lanteri & carabelli, ), we are nonetheless concerned with the observation that the price of a financial asset often deviates from the consensus view of the fundamental value of the asset in question. moreover, the price reaction to changes in fundamentals in a beauty contest is much more sluggish than that of the consensus fundamental value (allen, morris & shin, ). to put it differently, game- theory is used to understand and illustrate the role of higher-order beliefs in asset pricing as each market participant has the ability to affect the market price, and s/he knows that the others do as well. a typical illustration of a p-beauty contest game is when a large number of players simultaneously shall choose a number from a closed interval [ , ]. the person who chooses the number closest to p times the mean wins a prize. in case there is a draw, the prize is divided equally amongst the winners. to explain the process in a classic p-beauty contest game, p is normally set at / . assuming the guesses are normally distributed between and , the rational guess would there be two-thirds of , i.e. . but since others think the same, it would be (two-thirds of ), and so on. hence, for ≤ p < there is only one nash equilibrium, namely zero (see, for example: duffy and nagel, ; ho, camerer & weigelt, ; nagel, , ; nagel et al., ). in terms of a keynesian beauty contest, the libor, as a benchmark, should reflect the money market – and not vice versa. conceptually then, we could treat the money market rate (whether perfectly observable or not) as a kind of fundamental value, or a focal point, towards which the libor rate should aim. more specifically, the libor fixing mechanism can be viewed as a p-beauty contest game with more than two players where p = . to illustrate this, let us assume that the money market rate is common knowledge and that all banks face the same funding cost. banks in such a game would be driven by a desire to guess exactly the average of all guesses. theoretically, we have a coordination game with infinitively many equilibrium points in which all players choose the same number (ochs, ). however, in a libor game, we do have a natural focal point: the money market rate, which in this case is common knowledge. therefore, the money market rate could be regarded as the fundamental value, i.e. p = . the trimming process (the omission of the highest and lowest quotes from the calculation of the libor fixing) can be seen as a mechanism put in place to ensure that players remain alert and aim for p = in every round of the game. therefore, as players tend to avoid extreme endpoints (rubinstein et al., ), and also learn from the libor fixing of the previous day, outliers will increase their efforts not to be omitted the following day. thus, the original design of the libor fixing mechanism could be seen as a median-effort-game (cachon & camerer, ), where it is assumed that libor panel banks harmonise their behaviour following a learning process. however, recent investigations into the alleged libor manipulation have highlighted some underlying incentives that might distort this coordination process. for instance, banks might have libor-based derivatives portfolios giving them sufficiently strong incentives to submit libor quotes deviating from their actual short-term funding cost. from the perspective of a p-beauty contest game, these portfolios could be seen as endowments automatically forming three different types of players. players with endowments benefitting from a relatively low libor are playing a game where they should guess . a player with no endowment would continue to play p = . as a consequence, if some players face a game where p ≠ , the probability increases that the libor deviates from the actual money market rate, as players have different focal points depending on their underlying libor-indexed derivatives portfolios. this game could have different outcomes depending on the distribution of the types of players. another incentive relates to the stigma attached to signalling a relative high short- term funding cost through the libor fixing process. according to the british bankers association ( ), libor quotes are supposed to reflect ‘where the bank can fund itself in the interbank market’. therefore, an individual quote above the average of the panel quotes might be interpreted as a signal that the bank has funding problems relative to the others. likewise, a lower than average quote would signal that the bank is in relatively good shape – as individually submitted libor quotes are visible to the whole market, not only to the other libor panel banks after the fixing has taken place. the stigma incentive, thus, rewards players submitting a below-average quote – regardless of the actual libor fixing. in terms of a p-beauty contest game, the stigma incentive seen in isolation automatically implies that < p < for all players, rather than p = . however, despite the existence of these incentives, it is unlikely that players in the libor p-beauty contest game (or libor panel banks in reality for that matter) always aim to win the game at any cost. the libor (in terms of a game) would not have established itself as such an important benchmark without having some kind of constraints attributed to it. for instance, the frequent use of fixed intervals in p-beauty contest games is not without controversy, as it could be argued that the price drift of a financial asset often lacks typical boundaries. to some degree, the same could be said about the libor, which has experienced some sharp moves during times of crisis. nonetheless, the boundaries are hardly infinite, and some kind of fixed range of numbers or a tolerated-libor-range probably exists theoretically. it could, for instance, be argued that a zero-lower-bound of nominal interest rates could be applied to the libor as well (although this could change should the central bank in question decide to lower the policy rate well below zero). the upper bound might be high as the libor should reflect any liquidity and credit strains in the banking system. however, it still ought to correspond to some kind of worst-case-scenario where the central bank is perceived to be forced to step in by intervening in the money markets. after all, at some libor-level, banks become insolvent and should be removed from the fixing panel in question. another special feature of the libor fixing mechanism is the trimming process. to some degree, this process could be said to mitigate some of the distortions derived from the incentives, thereby ensuring that a sufficient majority of the players stick to p = . this, however, requires that the stigma incentive applies only to a small minority of the players, and that the endowments are perfectly offsetting and normally distributed among them. players in a p-beauty contest game could also be obliged to pay a fine whose size is determined by how far the chosen number deviates from the best guess (güth, kocher & sutter, ). in this context, we could see how the libor fixing mechanism could consist of formal, or informal, reputational fines or constraints facing all players. such a mechanism would be put in place to prevent players from submitting deceptive libor quotes, and in fact, during the era of the japan premium, japanese banks were consistently outliers in the libor fixing process. thereby giving them an incentive to adhere to fair play. from a bank’s perspective, the constraint could be interpreted as follows: submitting a deceptive quote might, if discovered, result in less client business, legal costs of being under regulatory investigation or even the risk of being excluded from the panel altogether and being replaced by another bank. the constraint could also be interpreted as affecting only the trading desk or treasury, if they were required to commit to their quotes in reasonable-market-size, where a deceptive quote would be exploited by other libor panel banks. another variant of the classic p-beauty contest game would be to rank the individual players according to how good they are perceived to be at the game (with their rankings being common knowledge). players would then receive a fine if they, on average, manage to outwit higher ranked players (in other words, choose a number that is lower than the average of the numbers guessed by the players ranked above her/him). the aim with this constraint would be to prevent the audience from distrusting the credibility and integrity of the game. although the outcome would be the same (in the case of p = / ), the process towards the only nash equilibrium, namely zero, would be slower. whichever type of p-beauty contest game is modelled, within each specific game, players need to anticipate what the others will do and what they will anticipate others will do and so on. using these particular features as our point of reference, we will now design a libor p-beauty contest game. rules of the libor p-beauty contest game to analyse the potential outcomes of the libor p-beauty contest game, we will first consider a hypothetical game with players (libor panel banks) played from t- to infinity. the libor fixing procedure is as follows. a calculation agent collects the submitted quotes from the individual panel banks before noon. the individual libor submissions are done simultaneously without the ability to see each others’ quotes. the calculation agent then conducts the trimming process, with omission of the highest and lowest quotes. thereafter, the arithmetic mean is calculated of the eight remaining libor submissions. let us assume that all banks face the same (largely known) funding cost (m) in the first round (at t- ) as they are perceived to be equally creditworthy and have similar access to liquidity. further, the banks have no libor-indexed derivatives portfolios acting as incentives to distort the fixing process. let us also assume that each player is only allowed to adjust their quotes by increments of basis points ( . %). furthermore, the tolerable libor range is [ . %, . %]. these are not necessary conditions but useful for the sake of simplicity and clarity of argument. from these assumptions, it is obvious that m is the clear focal point in this game and that all banks submit libor quotes at, or close to, the funding cost at the time (assumed to be, say, . %). in any case, outliers are omitted through the trimming process and the libor fixing will end up close to . % at t- . this corresponds to the p-beauty contest game where p = . if p = for all players, the money market rate can be seen as the natural focal point or fundamental value towards which the libor should drift. however, let us now introduce some new variables that capture a more realistic scenario. to be more specific, let four significant changes take place at t , having an impact on the incentives structures and beliefs of the players without altering the libor fixing mechanism itself. first, some players have an endowment (e), which is private knowledge and where e+ > , e = and e- < . the endowment is a derivatives portfolio benchmarked against the libor. for the sake of argument, let us simply assume that a player with a positive endowment (e+) benefits from a high libor, players with a negative endowment (e-) from a low libor and players with no endowment (e ) are indifferent. whereas the players know their own ps, they are not aware of the distribution of the ps among the others, as the endowment is private knowledge. consequently, the payoff from the endowment in each round depends on the sign and size of the endowment, as well as the change in the libor fixing (lf): �� , ( ) where � � �� . thus, each player has an incentive to submit a quote that maximises the expected change in value of the endowment from t- to t. in terms of a p-beauty contest game, this could now be seen as a game where we have three types of players not knowing what type the others are nor the distribution among them. player type (in other words e-) shall guess p times the mean where p = / , player type (e ) shall guess p times the mean where p = and player type (e+) where p = / . the strategy of each player will simply depend on the sign of the endowment in each round. second, a stigma is imposed on submitting a relatively high libor. this is directly caused by a credit crisis leading to a wider distribution of the perceived creditworthiness of the players (banks) by the market. let us assume that the crisis has resulted in an increase in the average short-term bank funding cost from . % to . %. specifically, we will assume that the ois price is unchanged implying that the increase in the short-term funding cost is purely a reflection of increased credit and liquidity strains in the money market. moreover, increased market uncertainly and volatility allows for larger day-to-day moves in libor quotes ( . % instead of . %), as well as a wider tolerable libor range [ . %, . %]. despite the importance of the libor as a benchmark, however, other indicators such as credit ratings or credit default swaps (cdss) matter also. put differently, the wider distribution of the perceived creditworthiness at t calls for the introduction of an independent and objective referee as well as an internal ranking system of the players. let us simply say that the referee is the market. the internal ranking system is market-determined in the sense that each player is allocated a place hierarchically according to how creditworthy it is perceived to be compared to its peers. the perceived creditworthiness of each individual bank is assessed by the observable -year credit default swap spreads in the market, which prior to t were identical. let us now assume that from t , the cds spreads are unequally distributed between the banks {a, b, c... p}, ranging from bps to bps. banka (cds = ) is perceived as the most creditworthy, bankb slightly less (cds = ) and so on. bankp is regarded as the riskiest with a cds spread of bps. let us also assume that the cds spreads remain constant throughout the game. as a result, the bank funding cost is now partly dependent on the long-term funding cost (the cds price which is public knowledge) and the short-term funding cost (which is private knowledge only but subjectively communicated through the libor submission). thus, each bank now not only wants to maximise the value of its libor-indexed derivatives portfolio but also wants to minimise the stigma (σ) attached to having a relatively high funding cost. in terms of a p-beauty contest game, some players now have conflicting objectives. on the one hand, they are playing a game where p = / , p = or p = / (depending on their endowment). on the other hand, all players now simultaneously play the same game where p < , as they would prefer to signal to the market that their short-term funding cost is slightly lower than their peers. the payoff from the stigma can be written as: �� , ( ) where λ and χ are constants. the rhs of the equation consists of two parts: the stigma derived from the long-term funding cost, and the stigma from the short-term funding cost (the libor). the long-term funding cost is exogenously determined and market-observable (proxied by the cds spread). the payoff from this stigma (σlt) cannot be influenced by the player’s actions as it is market-determined: �� ∑ �� ∑ �� ( ) however, the stigma derived from the short-term funding cost (σst) is endogenously derived from the libor fixing mechanism which the player has influence over. here, the individual banks can (and wish to) minimise the bank funding cost as it is perceived to be by the market: �� ∑ �� ∑ �� ( ) now, although the individual libor quotes are subjective and their accuracy therefore cannot be verified, it would be unrealistic to assume that the banks perceived as the least creditworthy (judging by their long-term cds spreads) have the ability to raise short- term funding more easily than their peers. importantly, the market is not indifferent, and would not find it credible should the individual libor quotes not correspond to at least some kind of ordering from the most creditworthy to the least creditworthy. in other words, this calls for the introduction of an credibility constraint, where each player is subject to a fine (denoted ‘ω’) should they signal a relatively too low funding cost, as the market (which is aware of the cds-spreads) would not regard it as credible if a bank claimed its short-term funding cost to be lower than those with lower cds spreads: �� ,�� ( ) finally, it is likely that players in the libor game are bound by some rules or constraints that relate to their reputation. this is to protect third-party actors with exposure to the libor from being affected by potential incentives which individual banks might have to abuse the system and submit either too high - or too low - quotes. this reputational- constraint could take different forms: as a requirement among the banks to trade a certain amount at the submitted libor quote, as a requirement by regulators to occasionally disclose underlying traders forming the judgement basis for the quote, or simply as a pre- agreed ‘gentlemen’s agreement’ among the panel banks to adhere to fair play. in each instance, players could be seen as being subject to a reputational fine (expressed as ‘�’) of how much their libor quotes deviate from the mean of the others: �� ∑ �� ( ) in sum, the new payoff function for each player can be written as follows: �� ,�� ∑ �� ( ) outcome: a process of endogenous deception before analysing the potential outcomes of this game, let us first recap the libor fixing at t- , which was . %. the credit crisis then resulted in an increase in the average short-term funding cost by . %. following the new restriction of only being allowed to move in . % increments in each round, the market should expect a libor fixing at . % at t , . % at t and finally . % at t , as each player gradually submits a higher libor quote. since the average short-term funding cost now is . %, which could be regarded as the fundamental value of m, we should theoretically expect this to be reflected in the libor fixing as time progresses. however, the new game now also more closely resembles that of the ‘real’ libor fixing mechanism, and new incentives and constraints apply. this implies a totally different outcome. first, the endowments changed the dynamics of the game. as libor banks are now given incentives to submit deceptive quotes, the quotes will now be more widely dispersed. players with small or no endowments at all (e ≈ ) have no incentive to submit deceptive quotes, and will therefore, on average, increase their quotes towards the expected . %. however, a player with e- would choose to submit . % and a player with e+ . % in the first round. what is more, they would gradually move towards the respective extreme points of the tolerated range ( . % and . % respectively). some quotes would naturally be omitted through the fixing process. nonetheless, the outcome after a number of rounds have been played will depend on the distribution of the endowments, and in this case also the learning process that follows from the signalling in each round. second, the reputational constraint (expressed as �) works as a hindrance to submit overly deceptive quotes, as the fine takes into account the size of the deviation from the average quotes. at the outset, the libor should drift towards . % in a few days as the average funding cost (which is public knowledge) has increased substantially. this knowledge should make players with e+ more comfortable in raising their quotes than players with e- in lowering their quotes. however, the reputational constraint prevents any player from adjusting her/his quote by a large increment as this could result in a reputational fine. should the groups with e+ and e- be equally distributed, the libor would have a tendency to move (albeit slowly) higher. likewise, should the e/�-ratio increase, players with large endowments would have the incentive to change their quote slightly more in their favour as the relatively small fine of being an outlier is outweighed by the possibility that others think and do the same. importantly, players with e ≈ cannot be safely assured that a fair quote or even a quote in a fairer direction will be left unpunished. the reputational cost occurs regardless of whether the player has an endowment or not, and imitating the crowd will consequently be necessary to avoid potential losses stemming from being an outlier. in fact, the mere expectation that players in a large sub-group (say with e-) will shift their quotes in one direction will prompt players with e to do the same, as they would (possibly unfairly) otherwise face a penalty from deviating from the mean. thus, at this stage the game can be seen as a situation where incentives are balanced against the constraint of having to imitate the crowd. third, the stigma of signalling a relatively low creditworthiness prevents players from submitting high quotes. now, since t , the individual bank funding costs are diverse. this in itself should imply libor quotes scattered around . % after a few days as the market expects the libor to trend toward its fundamental value. in fact, judging by the observable cds spreads, the market should expect some kind of ordering of the libor quotes from the best banks’ quotes well below % and the worst banks’ significantly above %. the trimming mechanism should ensure that the extreme outliers are omitted (those hardly affected by the crisis and those facing severe trouble). from the players’ perspective, however, the worsening perceived long-term, as well as the short-term, funding cost has a direct negative impact. in this game, the long-term funding cost is exogenously determined, expressed by the cds market. however, whereas the measure for the long-term funding cost is public knowledge, the short-term funding cost lacks transparency. instead, players are assessed according to their own assessments announced through their respective libor submissions. in both instances players are rewarded (or penalised) according to how they compare against their peers. thus, all banks now have an incentive to submit relatively low libor quotes to distance themselves from the others. fourth, leaving the endowments aside for a moment, the credibility constraint (ω) prevents all banks apart from banka to submit a relatively low quote at t , as they would automatically face a penalty not only from deviating from the others (the reputational constraint), but also from having submitted a non-credible quote (the credibility constraint). the market or the wider public, comparing the cds spreads between the players, would not believe that the player’s own assessment of its credit and liquidity standing is correct. if the reputational fine is small, but not non-existent, and the potential stigma payoff large, banka would have an incentive to signal to the market that its short-term funding cost indeed is much lower than that of its peers (by submitting, say, . %). at t , with the results from the previous round now taken into account within respective strategy decisions, bankb can safely quote . %, whereby banka has the opportunity to lower its quote a step further (to . %) in order to distinguish itself even further from the its creditworthy peers . at t , it is bankc’s turn to quote . %, whereas banka and bankb yet again opt to distance themselves further from the less creditworthy banks. seen in isolation, this process would continue until the nash equilibrium of . % is reached. however - and here is the essence of the p-beauty contest game - banks anticipate that the others will move. bankb can therefore safely quote, say, . % already at t , as s/he knows that the best strategy of banka is to quote . % (as s/he is also aware of the cds spread of the other banks). likewise, bankc anticipates that bankb anticipates that banka will quote . % and can therefore also lower its quote slightly – and so on. now, banka, in the first place, also anticipates that others anticipate her/his initial move and therefore takes this into already with her/his first move. the original design of the libor fixing mechanism (where p = ) implies that the average funding cost is . % and that the libor fixing should not trend lower but higher towards this fundamental value. the libor p-beauty contest game presented here, however, illustrates that even though the libor should trend towards . %, this process can be very slow or not happen at all. in fact, the game shows that the opposite can occur. this game is about imitating the crowd but at the same time trying to outsmart it slightly, with the knowledge that others will do the same. the combination of different incentives and constraints, and the anticipation of what others will do, results in a slow process towards an equilibrium not necessarily equalling the expected average funding cost of the panel banks. throughout this process, libor quotes can be narrowly distributed which might not be justified by the distribution of perceived creditworthiness among the panel banks. banks with strong incentives from the endowment or the stigma to submit deceptive quotes can be better off doing so in this game. however, even players seemingly without such incentives get caught up in this process. for instance, players with a bank funding cost precisely equalling the average of % can be penalised from not only finding themselves as unexpected outliers, but being required to signal a slightly higher creditworthiness than actually assessed internally. likewise, players with negligible or no endowments at all can become less focused on the fundamental money market rate than the anticipated libor-rate. in sum, even for the seemingly average and fair player, the libor p-beauty contest game becomes a loss-making process when not following the crowd. therefore, deception can be seen as a problem not specific to the behaviour of individual players, but systematic and endogenous to the libor fixing process itself. concluding discussion by regarding the libor fixing as the outcome of a unusual form of a p-beauty contest game, this article has illustrated how the libor can deviate systematically from what could be regarded as its fundamental value, namely the consensus view of where the average money market funding cost is. the trimming process has often been regarded as an effective prevention method against systematic manipulation. this assumes either that artificially low gyntelberg & wooldbridge ( ), for instance, acknowledge that libor panel banks, in theory, could act strategically in their fixing but that the trimming process acts as a hindering factor. and high quotes are normally distributed, or that a libor panel bank knows that a deceptive quote will be omitted from the calculation and therefore will be ineffective. however, the outcomes of the p-beauty contest game do not support these arguments. moreover, a typical libor panel composition is probably not heterogeneous but fairly homogenous at the outset. a common feature of all libor panels is that they largely consist of universal too-big-to-fail banks that are highly active (and normally market-makers) in the money, foreign exchange and derivatives markets. as the recent global financial crisis has shown, the distribution of their asset and liabilities is not randomly distributed but fairly similar. libor-indexed derivatives portfolios can act as incentives to submit deceptive quotes. what is more, there is nothing preventing libor banks from increasing or decreasing their own exposure to the benchmark they themselves can influence. systematically favourable libor fixings give the incentive to keep or increase the exposures while unfavourable fixings give incentive to reduce them. in the libor p-beauty contest game presented in this article, it would obviously pay for some players to collude through communication, should it be possible. for instance, a group of banks with identical endowments might want to mutually agree to opt for the same strategy to maximise the expected payoff, and consequently also share the reputational fine. moreover, communication and signalling becomes endogenous to the libor p-beauty contest game as it is played five business days a week and more than times a year. collusion might lead to quicker and more certain outcomes. however, a non-cooperative libor game can lead to the same results; although their ‘conception of the solution’ is totally different (schelling, : pp. - ). however, seen in isolation, the stigma attached to signalling a relatively high funding cost works against collusion as individual banks are judged individually compared to their peers. this is perhaps the single most important explanation why anecdotal evidence throughout the global financial crisis, as well as the recent investigations into the conduct of a number of libor panel banks, has suggested that the libor consistently has been too low. the results are therefore consistent with empirical studies suggesting underreporting of the libor by panel banks (abrantes-metz et al., ; monticini & thornton, ; snider & youle , ). the libor p-beauty contest game modelled in this article highlights another feature of the stigma: its relation to other financial indicators. if the long-term funding cost of a particular bank is observable through some market-determined process (such as the cds market), whereas the short-term funding cost is a kind of self-assessment (the libor), the former can act as a variable that influences the libor panel banks to submit deceptive quotes. this fundamental problem is highlighted through the credibility constraint in the game. it could be argued that the individual quotes by the libor panel banks should be ranked according to their perceived creditworthiness in the market, for instance by their respective cds-spreads. even though no such ranking systems officially exist, the continuous market assessment of long-term creditworthiness, and the libor banks’ awareness of it, induces a process whereby banks want to look good, but not ‘too’ good. the credibility constraint in the libor p-beauty contest game therefore shows that even though players at times might be ordered correctly, the distance between them depends on the other features of the game. in fact, the results show how the libor can have a tendency to observe a certain ‘stickiness’, and how the different libor quotes among the panel banks can be more narrowly distributed than would be suggested by other financial indicators. as such, it might give the false impression that the money market is stable and banks have fairly similar funding costs. finally, the reputational constraint appears as an incentive not to submit a libor quote that deviates too much from the others. a possible and striking outcome of this is the inability of fair players, with small endowments or an average funding cost level, to determine the outcome of the game despite their natural desire to harmonise their quotes around the fundamental rate. deception can become endogenous to the libor fixing process, and not deceiving is punished in a similar way as to paying above market for a distraught asset. consequently, as players are guided by higher order beliefs, some libor panel banks can be seen as being driven towards a behavioural pattern that is not dependent on their own incentives and constraints in the first instance, but generated endogenously though the process itself. deception in this case does not need to result from the self-interest of an individual libor submitter, but from the perception that others will act in such a manner that not submitting deceptive libor quotes would be punished. the privilege to be able to influence the libor rests with the libor panel banks. this exclusive right gives rise to significant power, which in turn becomes reinforced as ‘manipulation’ (whether conscious or unconscious) receives a kind of conventional status. as such, the current libor fixing mechanism is characterized by a fundamental and systematic flaw. the libor tends to react more slowly to unexpected rate moves, 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( ) libor games: means, opportunities and incentives to deceive. research on money and finance discussion papers, no. , soas, university of london. u.s. commodity futures trading commission ( ) cftc orders barclays to pay $ million penalty for attempted manipulation of and false reporting concerning libor and euribor benchmark interest rates, press release, june. available at http://www.cftc.gov/pressroom/pressreleases/pr - (accessed august, ). redalyc.miss venezuela: more than just beauty? academia. revista latinoamericana de administración issn: - esalgado@uniandes.edu.com consejo latinoamericano de escuelas de administración organismo internacional auletta, nunzia; helena jaen, maría miss venezuela: more than just beauty? academia. revista latinoamericana de administración, vol. , núm. , , pp. - consejo latinoamericano de escuelas de administración bogotá, organismo internacional available in: http://www.redalyc.org/articulo.oa?id= how to cite complete issue more information about this article journal's homepage in redalyc.org scientific information system network of scientific journals from latin america, the caribbean, spain and portugal non-profit academic project, developed under the open access initiative http://www.redalyc.org/revista.oa?id= http://www.redalyc.org/articulo.oa?id= http://www.redalyc.org/comocitar.oa?id= http://www.redalyc.org/fasciculo.oa?id= &numero= http://www.redalyc.org/articulo.oa?id= http://www.redalyc.org/revista.oa?id= http://www.redalyc.org miss venezuela: more than just beauty? nunzia auletta and marı́a helena jaén instituto de estudios superiores de administraci�on (iesa), caracas, venezuela abstract purpose – the case study centers on the ways in which a world-renowned beauty pageant is deployed as a strategic asset by the organizaci�on cisneros (oc), a major player among latin american television companies. the miss venezuela (mv) beauty contest has iconic status in venezuela and enjoys an international reputation. following the election of president ch�avez in the oc gradually scaled-down its operations in venezuela. adriana cisneros, oc vice president, turned mv into a key element of the corporate social responsibility strategy at venevisi�on, the tv channel founded by her grandfather. she also sought ways to build on the mv brand, in order to strengthen the oc’s business strategy. design/methodology/approach – the case study employs an inductive methodology, using a comprehensive approach to develop a teaching case study. it focusses on understanding a concrete business situation presented within a detailed contextual analysis. findings – complex business and strategic decision making calls for a thorough analysis of internal business variables and a deep understanding of complex environmental forces. originality/value – the comprehensive approach and detailed information presented in this case study constitute a versatile resource that will be useful for teaching topics including strategy, innovation, and business model development. keywords marketing, innovation, strategy, family business, product development, business models paper type case study the th miss universe contest was held in nassau, bahamas, on august , ; it had contestants. osmel sousa, president of the miss venezuela organization (mvo), was both anxious and delighted as he walked in and out of the imperial room at the atlantis paradise island resort. he had just received a congratulatory telephone call from adriana cisneros, vice president of the board and director of strategy at the organizaci�on cisneros (oc), because miss venezuela (mv) had been chosen as one of the ten finalists of the competition. sousa understood clearly that mv had little chance of success; mv had won the miss universe contest the previous year, and no country had ever won the pageant two years running. but much to his surprise, his candidate continued to advance in the selection process and was now paired with miss dominican republic. “it’s hard to believe,” he said to himself, but stefanı́a fern�andez was about to be crowned by dayana mendoza, her predecessor, as the sixth venezuelan beauty queen to win miss universe. the current issue and full text archive of this journal is available at www.emeraldinsight.com/ - .htm received july revised february accepted april academia revista latinoamericana de administraci�on vol. no. , pp. - r emerald group publishing limited - doi . /arla- - - prepared by professors nunzia auletta and marı́a helena jaén of iesa, with the assistance of researcher stefania vitale. case studies are developed for the sole purpose of serving as teaching aids for instructors in class discussion. case content should not be considered to be a primary source of information, does not indicate either the correct or incorrect handling of a management issue, nor support the views of persons or organizations cited. the teaching note is available from the authors upon request. published with the authorization of iesa. research for this article was completed in march . miss venezuela mvo has won six miss universe and five miss world contests (table i), becoming a well-known global brand. regardless of social class, venezuelan women viewed contest winners as role models. in addition to their beauty, many had overcome their modest origins, earning fame and fortune by dint of hard work. mv title holders were seen as exemplary venezuelan women, a symbol to be emulated. the oc’s top management had long viewed mv contests as the super bowl of venezuelan television, even as it mulled over new media opportunities to expand audiences, especially among younger viewers. in hugo ch�avez’s venezuela, venevisi�on (vv) struggled for higher ratings even after its chief competitor, radio caracas televisi�on, was removed from the air following the revocation of its state broadcasting license. in december , well over a year after that magic night in nassau, adriana was working on the oc’s strategic plan. she considered the future of mv to be her chief overall challenge. the mv organization the mv pageant was first held in , to select a representative for the first miss universe contest. in , ignacio font coll, head of the advertising agency oppa publicidad, purchased the venezuelan rights to the contest and turned it into a tv event. sousa joined oppa in . he soon proved skillful in identifying potential candidates for the beauty contest, and in understanding the kind of coaching required to win. recalling those early years, he said: i started out sketching for oppa, but once i became involved with the miss venezuela contest i saw that candidates required training: they had to learn to walk, understand what to wear, get a different look. we sought help from makeup artists, trainers of catwalk models, and designers who in later years would become world class, such as guy melliet and carolina herrera. maritza sayalero was the first venezuelan to win miss universe, in . public interest in the contest mushroomed in the wake of her victory. in , oc president gustavo cisneros bought the rights to mv. a run of the mill beauty contest was soon turned into mvo, directed by sousa, whose strict selection practices brought him fame as a “beauty czar.” the contest produced by vv and directed by joaquı́n riviera, vice president of oc’s variety programming unit, evolved into a tv show viewed in many countries. a double victory that same year, with irene s�aez as miss universe and maritza sayalero ( ) crowned in australia. a photo sequence considered sensational showed the first miss universe, a venezuelan, wearing a fur coat over a bikini irene s�aez ( ) crowned in new york. subsequently elected mayor of chacao, a greater caracas municipality, for two terms; presidential candidate in ; elected governor of nueva esparta state also in b�arbara palacios ( ) miss south america, winner, crowned miss universe in panama. for seven years, hostess of the mv contest alicia machado ( ) crowned in las vegas. her reign led to considerable controversy dayana mendoza ( ) crowned miss universe in vietnam after winning the mv contest as a model for the elite agency stefanı́a fern�andez ( ) crowned in nassau, bahamas. venezuela’s sixth crown, the second in successive years source: cisneros ( ) table i. miss universe contest winners - arla , pilı́n le�on as miss world, sparked worldwide interest in the beauty of venezuelan women, and ushered in a period when venezuelan women would win a record times in as many beauty contests and make dozens of final appearances. mvo was a small organization. sousa worked with four collaborators who assisted him in all aspects of the selection and grooming of candidates; yet he was viewed as “involved in every single detail” and enjoying total freedom in decision making. after years of leadership, he stated: here i do whatever i want. only the financial manager intervenes, as invariably i exceed my budget. gustavo cisneros never gets involved in the contest; he has always liked what i do; happily, we have been successful. sousa attributed the mvo’s success to “hard work, never letting up”; but others pointed to his natural esthetic skills, built on years of experience sketching and styling the female body and the fact he has served as society editor for a leading newspaper, a position from which he was able to spot fashion trends. work on the contest began each year in april, attracting as many as , applicants aged - . in , some were put forward by modeling agencies or referred by other parties, while several registered on the mvo web site, www.missvenezuela.com. about applicants got through to pre-casting. after two months of training and further selection, the number of candidates was narrowed to , equaling the number of venezuelan states. candidates then worked -hour days over a four-month period, at mvo headquarters in caracas, under a battery of nutritionists, psychologists, physical trainers, esthetic physicians, hairdressers, makeup artists and public speaking, and catwalk trainers (table ii). according to mvo’s coordinator marı́a kallay: mvo is a school for miss venezuela candidates. they must work very hard, learn a good deal, but suffer as well. they are heroines. these young women face a huge challenge because the pressure mounts as they begin to appear in public events. despite these demands, a spirit of camaraderie and sharing prevailed at mvo headquarters. candidates were reminded daily that they should “prove their worth to themselves only.” nonetheless, once public appearances began – such as at the beauty gala where candidates were presented to the press – competition surfaced and each candidate tried to find ways to stand out. time activity : - : gym. supervised by personal trainers in different gyms : - : transport to mvo headquarters : - : lunch. food specially prescribed for each candidate by a nutritionist. socializing : - : hairdressing and makeup. candidates trained in hairdressing and makeup, after weight and measurements are recorded : - : catwalk class. osmel supervises catwalk training by building on the personal style of each candidate : - : dance class. choreography training for the mv show at vv : - : public speaking. voice modulation and scenic presence, led by actor trainers : - - fashion designer session. selection of dresses and colors, led by designers source: callay ( ) table ii. a contest candidate’s day miss venezuela the training provided by mvo did more than prepare young women for a beauty contest. it has proved to be a springboard for many venezuelan women to build careers as actresses, tv entertainers, and in business. maite delgado, a leading vv entertainer known equally for her beauty, professional career, and role as housewife and mother, said: miss venezuela is a huge stage, not only for contest winners but also for those who lose. we learnt how to do everything: become candidates in a beauty contest, as well as dance, sing, and entertain. one of the best-remembered winners of mv was irene s�aez, the miss universe, who forged a political career and was elected mayor of the chacao district of caracas in and reelected in . she ran for the presidency in but was defeated by hugo ch�avez. subsequently, also in , s�aez was elected governor of the venezuelan state nueva esparta (margarita island), with more than percent of the vote. she served as governor until , resigning when she became pregnant. at that time, london times ranked her rd in its list of the most powerful women in the world. for vv, the professional development of mv candidates served as a deliberate strategy for shaping the channel’s actresses, broadcasters, and communications staff, as well as building a unique and positive image for venezuelan women. gustavo cisneros said: it was a way of grooming women for what we knew was the future, for women dominate tv broadcasting. women link us to a wide audience, just like the leones del caracas do too[ ]. it’s a great tie to the country, reinforcing the kind of values we promote: in miss venezuela, helping women to become successful and in baseball, because there’s an umpire and rules must be obeyed. there’s a civic sense in both activities; even though the two are very small businesses for the oc, they are huge in terms of promoting values for the country. the venezuelan public enjoyed a special, positive, relationship with mv contests, which were widely viewed as a way of promoting venezuela internationally. mv became a platform whereby women from all walks of life could get ahead. hinterlaces, a leading polling company, noted that, “in the venezuelan mind-set, mv means adherence to demanding training standards and striving for self-improvement, for misses are shaped, not born [y] what makes you a miss is performance, not adscription.” the mvo linked with the oc was positive because the oc was seen as a successful promoter of both the contest and the beauty of venezuelan women, augmenting the country’s image (table iii). mv contests were held once a year, but fans could keep themselves informed via the web page (www.missvenezuela.com), facebook (www.facebook.com/missvenezuela oficial) with , subscribers, twitter (@missvzla) with over , followers, and many other groups. social networks offered a space for interaction with younger audiences who could share their opinions on the contest, choose the design of the winner’s crown and support and promote their candidates of choice. they reinforced emotional bonding with the misses, as shown in the following tweet: “miss vzla universe @mvuniverso : thank u @giulym @mvuniverse greetings to the most beautiful miss venezuela ever [y] we all love you.” adriana recalled, alluding to the web page: we broke the once-a-year tv show pattern by publishing videos showing candidates in training, learning public speaking and parading on the catwalk. we also offered advice on how to use makeup or move elegantly. i look out for opportunities, and our business is to widen audience viewing figures. the web is an alternative space for advertisers at a more accessible cost; but it’s still new to venezuela. in this country, few people fully understand the potential of new media. arla , for the contest, the web became an interactive space where fans could choose the crown the new mv would wear, and directly elected their favorite on missvenezuela.com, as the web page slogan put it: “the miss that you elect” (figure ). the oc in , the oc comprised more than companies. it was described by forbes as a “diversified empire” that in over years had built a family fortune of usd billion (forbes, ), the second largest in latin america. its strategic focus was on the entertainment industry, specializing in tv production and broadcasting; other businesses dealt with telecoms, beauty, sports, education, and tourism (figure ). oc brands and services supplied over million consumers in the americas and europe, and its tv programming and other media content were distributed in over countries (cisneros, ). the oc was founded in venezuela in the early s by diego cisneros, remembered by his colleagues as a highly innovative leader who followed “the rule of the three cs: brains, heart, and courage [cerebro, coraz�on and coraje in spanish]” (bachelet, ). operations began with a small public transport business, soon followed by auto parts, home appliances, a pepsi-cola franchise, tı́o rico ice cream, and, in , the acquisition of vv. gustavo cisneros described the management style in place at oc as follows: we are a family business that still takes risks; we look after what we have but will not keep still. we will go forward, let’s call it risk-taking entrepreneurship. gustavo cisneros, one of diego’s sons, learned the business at vv, where he was still recalled as “a kid who fetched cables from the warehouse,” despite having graduated from the prestigious babson college business school and worked in the usa for abc television. gustavo cisneros became oc president in . he and his brother ricardo led the firm’s diversification throughout the decade and created a corporate central office to run the group. one branch of the business was vertically integrated to support miss venezuela has, over the decades, become a cultural industry, spawning beliefs, expectations, values, and perceptions about women in general, but particularly venezuelan women. moreover, the contest has shaped a multi-class and multiracial consensus in its favor the cultural influence of the contest has established and powered values and interpretations among average venezuelans that, for years, have contributed to its survival miss venezuela reflects the self-image of the venezuelan public, or its view of what it ought to be. the institution generates social beliefs that contribute to national self-esteem, the most widely known perception being that it is “the country with the most beautiful women.” but the contest also fosters the view that venezuela has the most entrepreneurial, the hardest working and the most combative and spirited women, who are committed to, and supportive of, other women as the visibility of venezuelan women on the world stage serves as a criterion for their success, the contest contributes to shaping expectations, a way of turning success into a key feature of the ideal of venezuelan womanhood similarly, the contest serves as a platform for social and economic progress for contest participants, offering them an additional opportunity to gain public fame and to develop personally and professionally. the contest therefore contributes to social mobility, the progress of women, and national development. it has become a symbol of hope for progress and a vindication of venezuela’s international image source: case writers based on company records table iii. symbolic impact of the miss venezuela contest miss venezuela pepsi-cola: bottles being made by oc company produvisa, for example, caps by corona and sugar by central portuguesa. business diversified swiftly: a liquor wholesaler, o’caña ( ); the cada supermarket chain ( ), founded by nelson rockefeller’s ibe corporation; and beauty aids manufactured by helene curtis industries inc ( ), a longtime sponsor of mv. international growth followed in the s, alongside expansion in venezuela: in the usa the oc acquired all american bottling ( ), spalding and evenflo ( ); in spain, the galerı́as preciado department stores; and real estate holdings in the uk. by , the oc had become latin america’s largest privately owned group, with some companies and , employees. in venezuela, the oc acquired the sears roebuck department stores ( ), turning them into maxy’s and a beverage producer, yukery ( ). in , vv international was founded in miami, florida, to produce and market tv content for the us hispanic and ibero-america markets. companies such visits: , , visits/day: , unique visitors: , , pageviews: , , daily visits pages/visit: . bounce rate: . % avg. time onsite: : new visits: . % venevision.com , , , , , , , / / / / / / / / / / / / / / / / / / / / / / / / monday, september start of crown voting monday, august miss universe friday, june soccer world cuplate january end of professioanl baseball season thursday, october miss venezuela facebook total global: , fans twitter venevision: , followers visits: , , visits/day: , unique visitors: , pageviews: , , daily visits pages/visit: . bounce rate: . % avg. time on site: : new visits: . % missvenezuela.com source: company records facebook missvenezuelaoficial , fans twitter missvzla , followers , , , , , , , / / / / / / / / / / / / / / / / / / / / / / / / monday, august mis universe monday, september start of crown voting saturday, october beauty gala thursday, october mis venezuela figure . web traffic: venevisi�on and miss venezuela arla , as rodven international ( ), a music company, and tv producer videom�ovil ( ) were expected to expand oc presence in the entertainment business. according to ceo steven bandel, up to this time the oc vision had been to “build on opportunities that often surface together,” yet to keep in mind viable “exit strategies.” while the s ushered in sweeping financial, political, and social uncertainty in venezuela, the oc focussed on internationalization, coupled with disinvestment in venezuelan consumer goods firms. according to oc president gustavo cisneros, “a company that cannot internationalize has no justification.” in , the cada and maxy’s chains were sold to colombia’s cadenalco for usd million. most growth took place in the tv and entertainment business: the oc acquired chilevisi�on, and a share of univision communications ( ), the leading company in the us hispanic market; launched galaxy latin america ( ), the first satellite-based home tv cable service that later became directv; founded the cisneros television group ( ), aimed at offering tv cable services; and acquired imagen satelital ( ), a leading pay-tv service in argentina. recalling these years, oc executive vice president carlos bardasano said: it was what could be called well-managed audacity [y] univision was bankrupt when we bought it. we obtained a usd million loan to finance our share and it turned out to be one of our best business ventures before we sold it in for usd . billion. after , activities centered on tv content platforms: claxson interactive group ( ), a multimedia content provider, and vv productions ( ), targeted on the hispanic tv soap opera market in usa. despite complex yet sustained growth, labor relations as well as management supervision were based on trust and responsibility. corporate affairs vice president antonieta mendoza de l�opez said: this is a decentralized holding, built on business units in different countries, where each unit is responsible for management accountability. we are linked by an entrepreneurial spirit coupled with decision-making power, and by the challenge posed by the oc’s owners to always stand ahead of the curve. we simply don’t know what it means to take our feet off the gas. organización cisneros saeca tourism sports sbs sports business leones del caracas fisa beauty organizacion miss venezuela digital latin america el sition digital channel siente music entertainment venevision venevision lnternational venevision plus venevision productions venevision cotinental venevision intl. productions venevision intl. publishing claxson vene movies vene music venemobile americatel bsp itc latcel summa sistemas csr fundación cisneros cppc ame cl@se source: case writers adapted from cisneros ( ) figure . organizaci�on cisneros miss venezuela management planning was project based; managers were given flexibility to select and pursue new businesses opportunities as they arise. yet, as mvo president sousa had put it, “nothing is improvised.” it was an organization that paid close attention to detail, where perfection was sought but errors tolerated, and where financial budgeting played a core role in operations. bandel stated: we prefer to make mistakes than keep everything under control. but in budget and planning meetings we stay focused on the numbers. we congratulate our people, and the key questions are “what are you planning to do? what new projects are there? why didn’t this work out?” people were closely supervised, making for visible promotion decisions and improved pay. bandel said: there’s a way gustavo recognizes you; people who bring something different are identified [y] regardless of potential success or failure. we reward people on the basis of what they try to do, not how much profit they have made or how much they lost; this makes managers feel ownership of the business. oc vice presidents spoke of a mix of work methods, teamwork, and loyalty. according to bardasano: the key lies in work methods, with a select team of top managers and a great deal of loyalty – a feature we all learned from don diego, that is followed today by gustavo and adriana. those of us who are long timers have served the organization for over years. in , according to legal consultant luis emilio g�omez: only percent of the co portfolio was made up of businesses based in venezuela, percent operated in the us, and there was an incipient entry into terrestrial digital tv in spain. despite having sold univision, the oc maintained a programming and distribution agreement for vv outputs in the usa: a natural route to serve hispanic audiences was ensured up to . reflecting on the future, bandel commented: we employ a two-fold strategy. on the one hand we focus on our core business, centered on content production and distribution, on a technology context where everything converges on different screens – pc, tv or mobile – and where the consumer reigns. but we must also seek businesses where we can create value and that we might subsequently sell. as gustavo cisneros puts it, if we spot a diamond on the floor we must pick it up. the cisneros foundation (cf) the cf was a private, not-for-profit organization founded in by patty and gustavo cisneros. in , adriana became head of the cf, and after taking on her post at the oc, she made corporate social responsibility (csr) a centerpiece of the foundation’s strategy. the cf’s mission was to “improve education in latin america and foster global knowledge of the region’s contribution to world culture” the mission derived from gustavo and patty cisneros’s hopes for the region: “[to] strengthen the values that characterized their business: democracy, free trade, hemispheric integration, economic development centered on social need and the application of technology as a transforming social force” (fundaci�on cisneros, ). the cf’s main projects were the patricia phelps de cisneros collection (cppc), think art, upgrading schoolteachers (ame), and cl@ss, which was responsible for arla , oc’s vision of csr, aimed at fostering sustainable development and social capital in the region. the cppc was founded in to promote latin american art and foster excellence in art education across the region. ame provided support to schoolteachers and educators. its aims were to develop programs based on art appreciation to foster critical thinking and problem solving. ame operated in countries, employing a distance-learning platform to offer school teachers training to upgrade the curricula in the areas of literacy, mathematics, environment, health, ethics, and information technology. cl@ss was an educational channel, featuring cultural, language, mathematics and science programming, and entertainment for schoolteachers across the region. according to csr managing director marı́a ignacia arcaya: in ame, together with the cl@ss channel, enabled the oc to draw on the directv satellite network by launching a csr product focused on education. adriana was convinced that it was necessary to fulfill the intentions that originally underlay the relationship between the oc and the cf, not only because they reflected family and company values, but because in practice the two organizations had always worked together. in her words: oc and cf projects are the same. looking back, my father would not have been able to grow the majority of his businesses had he not found ways to couple them with the social conscience he felt for latin america. nowadays social investment projects are a key feature of all our business ventures, and cf strategy has always been managed hand in hand with that of the oc. following organizational restructuring in , csr strategy was linked directly to the business plan, under the leadership of corporate affairs vice president antonieta mendoza. according to arcaya: the transition at cf required considerable coordination with my post in the corporate area. from the start we envisioned what the key messages and projects would be. we sought to articulate and structure what the oc and the cf had been doing for years, but had not publicized adequately. in , the oc decided to link mv to its csr strategy. according to mendoza: this decision was welcomed by mvo leaders, including osmel. in , for the first time, the miss venezuela show featured a -minute video showing csr activities undertaken by contest candidates. nonetheless, mendoza perceived certain risks: the public might think we were simply working on corporate image, overlooking the two-fold value being generated: first, contest candidates were primed on the millennium development goals, children’s rights, and our csr principles and values; and second, communities would benefit. thus, the contest took on a different stance, more human, more in tune with the country: the image of a beautiful woman who also showed social awareness. activities were undertaken at the mano amiga school, located in a rural area, where the cisneros family owned a property. contest candidates, together with ballplayers from the leones del caracas, played with the children in environmental workshops. in , in partnership with the iesa (institute of advanced studies in administration), an entrepreneurship program was set up for women in vulnerable circumstances, and contest candidates participated in classroom motivational activities. miss venezuela as arcaya noted: we combined the objective of building on the social capital of brands such as miss venezuela and leones del caracas with our own traditional focus on education. these two brands, beauty and baseball, linked with the values of self-improvement and success, represented a potential emotional bond with the venezuelan public, much needed in a complex and polarized social and political context. president hugo ch�avez’s venezuela hugo ch�avez was elected president of venezuela in , remaining in power in . he implemented a “bolivarian” revolution, dedicated to creating “ st century socialism.” in his administration remained popular but faced growing opposition. toward the end of the year, the country was warming up to the presidential election campaign, in which ch�avez expected to run for the fourth time. venezuela was perceived as a polarized country, with an electorate split into three large segments: pro-administration, pro-opposition, and non-aligned, the latter known colloquially as the ni-ni (neither-nor). this group included medium and lower income segments, and was chiefly comprised of women and younger voters. in the management consultancy odh grupo consultor reported that over a ten-year period extreme poverty had declined from to . percent, while general poverty had fallen from . to . percent. between and , venezuela steadily climbed the un human development index, number (united nation development programme, ). men and women had similar labor conditions: percent of women worked outside the home, vis-à-vis . percent of men (datos, ). in a country with three million entrepreneurs ( . percent of the population), percent were women (iesa-gem, ). venezuelans were recognized internationally for the value they placed on beauty, with both men and women ranking highest worldwide for vanity. among women, percent were constantly thinking about their looks, vs percent of men. women allocated roughly percent of their budget to purchasing goods and services linked to personal appearance. even on a low budget, women preferred not to forego their consumption of “beauty products, although they may reduce the variety of products they buy and purchase less frequently” (esqueda et al., ). by , venezuela’s economy was one of the worst performing in latin america, with an inflation rate of percent (table iv). following five years of rapid economic growth fueled by high oil prices, the economy declined in and gdp fell by . percent in the first half of . private investment suffered significant disincentives, dependence on imports rose, and access to foreign exchange was restricted (puente and gutiérrez, ). conindustria, the country’s leading industrial association, reported that firms were expropriated or confiscated in . venezuela was considered one of the riskiest countries for investment in the region (pablo, ). under ch�avez, many laws were passed to regulate mass media. the balance of private and public radio broadcasting was altered, with a greater concentration of government and community-operated stations (urbina serjant, ). the telecoms law (lotel) (comisi�on legislativa nacional, ), together with the radio and tv social responsibility law (resorte law) (asamblea nacional de la república bolivariana de venezuela, a), reinforced the regulatory role of the state over the media and intervened in content; and a revised penal code (asamblea nacional de la república bolivariana de venezuela, b) established that citizens could be jailed for arla , y ea r g d p (m il li o n u s d in , d o ll a rs )a p er ca p it a g d p (u s d in , d o ll a rs )a g d p y ea rl y ch a n g e (% )a p er ca p it a g d p y ea rl y ch a n g e (% )a in fl a ti o n (y ea rl y )b o ff ic ia l ex ch a n g e ra te (b sf � u s d )b , . . . . . , . � . � . . : . : . a n d . y ea r a lt er n a te o ff ic ia l ra te (b sf � u s d )b u n em p lo y m en t ra te (% )c p er ce n t p o o rc h u m a n d ev el o p m en t in d ex (h d i) d y ea r p re si d en t’ s a p p ro v a l ra ti n g (% )e n o t y et a v a il ab le . . . /h ig h h d i : . . . . /h ig h h d i . s o u r c e s : a u n it ed n a ti o n , e co n o m ic c o m m is si o n fo r l a ti n a m er ic a a n d th e c a ri b b ea n ( ); b b a n co c en tr a l d e v en ez u el a (b c v ) ( ); c in st it u to n a ci o n a l d e e st a d ı́s ti ca s (i n e ) v en ez u el a ( ); d u n it ed n a ti o n d ev el o p m en t p ro g ra m m e ( ); e c o n su lt o re s ( ) table iv. venezuela: social and economic indicators ( and ) miss venezuela “lack of respect” shown to government officials. lotel article stated: “the radio broadcasting spectrum is a public domain, use and exploitation of which are subject to a respective concession.” it also said that “the content of transmissions or communications [y] may be subject to limitations and restrictions for reasons of public interest.” in december , venezuela’s national assembly approved a reform of the lotel, extending it to apply it also to digital media (asamblea nacional de la república bolivariana de venezuela, ). the journalist marcelino bisbal argued that venezuela was a “media-led society,” that “the media, not politicians, granted internal structure to society” (table v), and that television was “the medium with greatest penetration and impact” (bisbal, ). the media had played a key role in times of political turmoil, such as when the administration of president carlos andrés pérez ( - ) faced two attempted coups promoted by ch�avez. following the first coup attempt (february , ), ch�avez became a media icon. to persuade his comrades to cease fire, he declared on live tv: i wish a good morning to all the people of venezuela. this bolivarian message is directed at the valiant soldiers now at the aragua paratroop regiment, and at the valencia armored brigade. comrades: unhappily, for now, the objectives we sought have not been achieved in the capital city (analitica.com, ). the expression “for now” (por ahora) became a popular slogan with strong emotional connotations. once he became president in , ch�avez’s love of public attention led to a weekly tv show hello president (al�o presidente) on the state channel venezolana de televisi�on (vtv), which by had broadcast shows. during the events of april - , – depicted by the government as an attempted coup, and by the opposition as a power vacuum – ch�avez’s supporters took control of vtv to call on his followers to demand his return to power, while claiming that privately owned media outlets were conspiring against the president. ch�avez and gustavo cisneros were brought together in june by former us president jimmy carter. after the meeting ch�avez stated: “there was no honor pact with anyone, my only pact of honor is with the people” (al�o presidente episode , ). at that point cisneros announced vv’s decision to “offer balanced programming, making equal space available to all political tendencies.” marcelino bisbal, journalist, head of graduate studies, catholic university andrés bello (ucab) “it’s a commonplace to hold that the media have supplanted politicians, at the same time as the media often dismiss, or even ‘don’t understand’, that they have become the chief players in a politicized society. not that the media wish to turn into political parties, but the way in which they build and rebuild reality, creating society, makes them behave as though they were political parties either in government or opposition [y]” “we are part of a media-led society and the media, not the politicians, provide society with internal structure [y]” accordingly, even if the idea appears overly crude, nowadays “[y] media representation has become a new social project that gives structure to society; i.e. we are discovering that new kinds of social relations have been shaped by the media. they are the “here and now” of the public arena -a virtual arena but no less real for that- that reflects our existence and where citizens are coming into being who are different from those we are familiar with: they are media citizens, part of a media civil society. roles have changed: people power, citizen power, has been passed on to the media – including political party power; government action has been supplanted by these new protagonists. there was a time when the media acted as bridge and messenger, but now they have become the chief actors in new and in old scenarios source: bisbal ( ) table v. opinions of venezuelan communications specialist arla , vv: a generalist channel vv first went on air on february , , following its acquisition by diego cisneros from televisa de venezuela, which had declared bankruptcy. don diego was convinced tv could contribute to strengthening what at the time was a young democracy. from the start, and as recently as , programming was described by vv executive vice president manuel fraı́z as “generalist, featuring news, sports, family and children’s entertainment and with a special focus on women.” from , this positioning was reinforced by the slogan “pure entertainment.” for over years, vv had differentiated its production and programming by featuring musical shows with live audiences (super sensational saturday), game shows (war of the sexes) and comedy (how crazy!). news and talk shows were hosted by well-known journalists, and the editorial line claimed to be “balanced and fair.” key differentiated productions were soap operas which, from , with the success of lucecita, became a leading export to latin american markets. soap content evolved from sentimental, tear-jerking stories to real-life drama that mirrored venezuelan society and its social conflicts. in , prime time, high rating, vv programming was dominated by soaps. the us-based vv international exported vv soaps to some countries, translating them into languages. a radical change in tv production took place in following the approval of the resorte law, which promoted local independent producers, generally individuals or small companies to which open-signal channels were required to allocate at least percent of their programming. concurrently, exchange controls limited the acquisition of international productions. the law also introduced a strict classification of programs and content. according to oc executive president miguel dvorak: restrictions contained in the law on both content and scheduling led to programming changes, often removing the realism the public sought in soaps and other programs. this increased costs, as we produce one version for export and a local version to comply with the law. vv led audience ratings in open-signal tv, with an average rating of . percent and a percent share (figure a, b and table vi). it was followed by televen (channel ), which registered steady growth, featuring canned programs from the usa together with highly rated brazilian soaps. vv’s traditional competitor, radio caracas tv, had been forced to migrate to cable in after conatel, the government’s regulatory agency, revoked its broadcast concession and cut off transmission in venezuela. dvorak added: spirited but loyal competition between vv and radio caracas tv fostered better programming. one channel or another was always ahead of the other. we now seem to have lost our compass; maintaining local production has become increasingly complex. the market was also influenced by cable tv. official data noted that cable reached percent of households, but in low-income areas unauthorized cable services were said to reach percent. cable tv offered more than local and international channels, with highly segmented programming aimed at youth and children (mtv, disney), followed by channels catering to women (fox life, universal) and sports fans (meridiano, espn). efforts to tap-specific audiences, even though coverage indicators were not high, had led advertisers in venezuela to assign cable tv about percent of an overall outlay of usd . billion in (figure ). fraı́z remarked: competition is tough. local and community channels, and certain cable services, take small bites out of the overall advertising spend, but added up it impacts all open-signal tv. for advertisers the decision is rendered more complex, as in order to obtain frequency and reach they must buy into all channels together. miss venezuela vv developed a web presence in order to adapt to media trends (www.venevision.com/). overall web penetration was estimated at percent, with over percent among youth audiences. viewers could obtain program information, videos, streamed news, games, and even share in programming decisions. advertising offered were launched featuring new formats – videos, games, mailing, banners, and photo galleries – that combined web site presence with social networks like twitter and facebook. o ct - no v- di c- en e- fe b- m ar - ab r- m ay - ju n- ju l- ag o- se p- . . . . . o ct - no v- di c- en e- fe b- m ar - ab r- m ay - ju n- ju l- ag o- se p- o ct - no v- di c- en e- fe b- m ar - ab r- m ay - ju n- ju l- ag o- se p- o ct - no v- di c- en e- fe b- m ar - ab r- m ay - ju n- ju l- ag o- se p- women abcde + men abcde + teenagers abcde - children - notes: (a) audience data (october -september ); (b) audience segmentation source: company records women + abcde men + abcde teenagers - abcde children - abcde figure . audience information arla , vv employed a staff of , in , plus another indirect employees – most of whom were talent hired under project contracts, such as actors, singers, and screenwriters. more than , program hours were scheduled annually. physical plant measured more than , square meters, plus dozens of mobile units. vv employed technology both to transmit and receive program content via satellite. its open-signal transmissions reached percent of venezuelan households. as its concession would expire in , it was absolutely necessary to comply at all times with the demands of the regulatory agencies. televen ( ): started operations in . owned by omar camero. generalist channel featuring information, opinion, drama, childrens’ and sports programs, and films. open signal, national coverage, distributed by satellite cable services. www.televen.com globovisi�on ( ): owned by the zuloaga family for years. critical of the venezuelan government. open signal for caracas and valencia, cable elsewhere in the country. news and opinion. target audience: “venezuela’s middle class.” www.globovision.com vtv ( ): venezolana de televisi�on (vtv), leading state-owned channel, started as a private channel in and nationalized in . now focuses on news and opinion, shifting its traditional variety programs to tves. www.vtv.gov.ve tves ( ) tves: state-owned, using the signal formerly used by radio caracas television before its concession lapsed and was not renewed by the telecoms regulatory agency. most programming is purchased and not of recent origin channel i ( ): formerly a music channel (pumatv). in - tried to compete with globovisi�on. sold by william ruperti to a canadian firm owned by radio caracas television shareholders, bc. variety programming. www.canal-i.com cable: supercable, intercable (now inter), and directv are the leading cable tv providers, featuring venezuelan and international channels chiefly from the usa and latin america source: case writers based on channels web sites (accessed ) table vi. venezuelan tv channels crm, % btl, % billboard, % magazines, % trade mktg, % tvos, % pop, % radio, % cable, % press, % source: company records figure . advertising investment (october to september ) miss venezuela show of the year in october , vv production facilities, directed by vice president of variety programming joaquı́n riviera, were preparing for the show of the year. as riviera noted: miss venezuela is our biggest event, taking up the most hours and creativity; it generates huge expectations from the public, making it a serious event for us. everywhere people ask me about miss venezuela and what’s planned for this year. the cost of the show was usd . million (table vii and figure ), justified on the grounds of gustavo cisneros’ vision of producing “the world’s best beauty program.” no effort was spared to surprise the audience and to connect with younger viewers by booking the most popular singers. in , the show was moved for the first time to the city of maracaibo, in search of an adequate location given difficulties in hiring the state-owned caracas polyhedron, and to enable it to get closer to people living outside the capital city, despite the higher costs this implied. the spectacle took five months to prepare, and involved more than , people. in addition to the candidates who were engaged in learning their choreographed moves, revenues , , , , , , revenues (% change) costs , , , , , costs (% change) � gross profits , , , , operating expenses , op. expenses (% change) operating profit or loss source: case writers estimates table vii. miss venezuela estimated income statement (thousands us$) sports, % drama, % source: case writers based on company records news, % ind. prod., % variety (mv), % figure . vv production costs distribution arla , there were three tv presenters, a dozen invited artists, dancers, security and technical staff, plus stylists, makeup artists, and hairdressers. entertainers for the show included three former mv winners who had gone on to become tv personalities – maite delgado, viviana gibelli, and chiquinquir�a delgado – as well as boris izaguirre, a venezuelan presenter with his own tv show in spain. the show opened with a dance performance based on the music and style of lady gaga, followed by the appearance of reggaeton[ ] stars chino and nacho. thought was also given to the senior audience and sections were included featuring traditional music. this was the second consecutive year to feature mv candidates participating in csr activities, reinforcing the image of venezuelan women – beautiful, triumphant, and yet predisposed to solidarity. pre-show promotions, media presence, public events attended by contest candidates, fan networks, and showbiz gossip about the potential winner provided the show with far greater space and better value for sponsors than would have been warranted by its one-night presentation. a small number of companies shared exclusive sponsorship of the event, among them l’bel, colgate, and kellogg’s, negotiated on the basis of annual contracts exceeding usd , when presold, and usd , under usual terms. the package included sponsor presence in all contest and beauty gala announcements, plus five -second commercials during both events. additional revenue was obtained from the sale of advertising space during the show, with as many as companies investing up to usd , each for a -second spot, in exchange for percent rating and percent share among open-signal channels (figure ). dvorak commented on the economic returns of mv, noting that he strived for equilibrium in “satisfying, within tolerable limits for the business in terms of budget goals and returns, the creative vision of joaquı́n riviera and osmel sousa.” as mv was the most expensive show on venezuelan television, in part because it was transmitted live to other latin american countries, the impact on return could well others, % cable, % televan, % mer tv, % tves, % globovisión, % vtv, % source: company records venevisión, % figure . miss venezuela show audience share (october , ) miss venezuela prove negative were production demands not subject to strict control. yet dvorak claimed: independently of production costs or revenue obtained from franchising, which has had its good and bad times, miss venezuela is an event that connects venevisi�on to the country, and especially to venezuelan women. reflecting on the role of mv in vv business strategy, fraı́z said: it’s a musical show that can be exported, but we could take it to a different level by turning it into a regional event, with participation not only of venezuelan contestants but others from a large number of countries. osmel’s experience in the univision show “our latin beauty” proves there’s an opportunity to export the beauty theme. adriana cisneros on december , on december , , just days after the new lotel and resorte law reforms were passed, adriana was aware that vv’s concession would expire in when it would have to be renewed by the venezuelan government. she also pondered the previous day’s strategic planning meeting with oc top management. it had been an intense working session, highlighting divergent views on mv’s strategic potential. she recalled views expressed by participants in the meeting, reflecting that it would not be easy to reconcile bandel’s expectations with those of sousa and riviera, not to speak of fraı́z and dvorak. mendoza insisted on reinforcing csr strategy, to bond with venezuelan society. bandel made it quite clear he wanted to connect vv to a new generation of viewers and make changes in the show’s format, with an international vision at that, bearing in mind that percent of oc business was outside venezuela. sousa wanted to increase efforts to ensure mvo was in a position to keep on winning international contests. riviera dreamed of coming up with another surprise for his show. what appealed to fraı́z was how to strengthen programming to keep the venezuelan audience. finally, dvorak looked to growing mv into a bigger and more profitable business. adriana was well aware that any decision taken would impact several levels of management. later that day she boarded a flight to new york, and continued to mull over the future of mv: miss venezuela is not just a beauty contest, but one of the flagship products of venevisi�on, the channel founded by my grandfather. the channel represents the main bond between my family and our country. as a product and a brand, mv has a potential we have not fully developed in our international operations; but a wrong decision could alienate the venezuelan public, or the new generation of viewers on whom the future of the business rests. what should i do? notes . acquired in , a professional baseball team, which has won championships. . reggaeton was a dance music style, very popular with young people across latin america. references al�o presidente episode ( ), “venezolana de televisi�on”, june, . . analitica.com ( ), “palabras del teniente-coronel hugo ch�avez el de febrero de por la televisi�on”, available at: www.analitica.com/bitblio/hchavez/ f.asp (accessed july , ). arla , asamblea nacional de la república bolivariana de venezuela ( a), “ley de responsabilidad social en radio y televisi�on”, gaceta oficial de la república bolivariana de venezuela, año cxxxii mes iii. asamblea nacional de la república bolivariana de venezuela ( b), “c�odigo penal”, gaceta oficial de la república bolivariana de venezuela, año cxxxii mes vii. asamblea nacional de la república bolivariana de venezuela ( ), “ley de reforma parcial de la ley de responsabilidad social en radio y televisi�on”, gaceta oficial de la república bolivariana de venezuela, año cxxxviii mes iii. bachelet, p. ( ), gustavo cisneros: empresario global, editorial planeta, bogot�a. banco central de venezuela ( ), “informaci�on estadı́stica”, available at: www.bcv.org.ve/c / indicadores.asp (accessed july , ). bisbal, m. ( ), “medios, ciudadanı́a y esfera pública en la venezuela de hoy”, quorum académico, vol. no. , pp. - . bisbal, m. ( ), “los medios en venezuela, +d�onde estamos?”, espacio abierto cuaderno venezolano de sociologı́a, vol. no. , pp. - . callay, m. ( ), “interview for miss venezuela’s case preparation”, interviewed by nunzia auletta, october, : . cisneros ( ), “a global enterprise, years strong”, available at: www.cisneros.com/ businesses (accessed july , ). comisi�on legislativa nacional ( ), “ley org�anica de telecomunicaciones”, gaceta oficial de la república bolivariana de venezuela, no. . , pp. - . consultores ( ), “popularidad de ch�avez bajo puntos en años”, available at: www. reportero .com/ / /consultores- -popularidad-de-chavez-bajo- -puntos-en- anos/ (accessed july , ). datos ( ), pulso del consumidor venezolano, empresa datos, caracas. esqueda, s., hern�andez, l. and herrera, c. ( ), “la belleza es otra cosa”, debates iesa, vol. no. , pp. - . forbes ( ), “the world’s billionaires # gustavo cisneros & family”, available at: www.forbes.com/lists/ / /billionaires- _gustavo-cisneros-family_gx f.html (accessed july , ). fundaci�on cisneros ( ), “fundaci�on cisneros”, available at: www.fundacion.cisneros.org (accessed november , ). iesa-gem ( ), “global entrepreneurship monitor”, informe ejecutivo, - , iesa – gem, caracas. instituto nacional de estadı́stica de venezuela ( ), “indicadores sociales: fuerza de trabajo”, available at: www.ine.gov.ve/index.php?option¼com_content&view¼category&id¼ &itemid¼ (accessed july , ). pablo, e. ( ), “el arriesgado negocio de invertir en venezuela”, debates iesa, vol. no. , pp. - . puente, j.m. and gutiérrez, h. ( ), “la economı́a venezolana: +y si el milagro no llega?”, debates iesa, vol. no. , pp. - . united nations economic commission for latin america and the caribbean ( ), statistical yearbook for latin america and the caribbean , united nations, santiago, available at: www.eclac.cl/publicaciones/xml/ / /lcg b_contenido.pdf (accessed july , ). united nations development programme ( ), human development report . the real wealth of nations: pathways to human development, united nations development programme, new york, ny, available at: hdr.undp.org/en/media/hdr_ _en_complete_ reprint.pdf (accessed july , ). miss venezuela urbina serjant, j. ( ), “venezuela”, las mordazas invisibles: nuevas y viejas barreras a la diversidad en la radiodifusi�on, amrc alc, asociaci�on mundial de radios comunitarias américa latina y caribe, buenos aires, pp. - , available at: www.amarc.org/ documents/books/libro_lasmordazasinvisibles.pdf (accessed july , ). further reading united nations development programme ( ), human development report . overcoming barriers: human mobility and development, united nations development programme, new york, ny, available at: hdr.undp.org/en/media/hdr_ _en_complete.pdf (accessed july , ). about the authors nunzia auletta is a full professor in the entrepreneurship and marketing centers at the instituto de estudios superiores en administraci�on (iesa), caracas, venezuela. she has a phd in political science and an mba. professor auletta has carried out research on entrepreneurship, family businesses and innovation, and coordinated the global entrepreneurship monitor (gem) and the successful trans-generational entrepreneurship practices (step) research teams at the iesa. nunzia auletta is the corresponding author and can be contacted at: nunzia.auletta@iesa.edu.ve marı́a helena jaén is a full professor in the management and leadership center at the instituto de estudios superiores en administraci�on (iesa), caracas, venezuela. she was a visiting scholar at the harvard business school, and a cisneros visiting scholar in the david rockefeller center for latin american studies at the harvard university ( - ). she has a phd in development studies in social sciences and masters in public health. professor jaén’s research focusses on business ethics and social responsibility, change management, management education and learning. to purchase reprints of this article please e-mail: reprints@emeraldinsight.com or visit our web site for further details: www.emeraldinsight.com/reprints arla , wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ veiling an indian beauty: shakespeare and the hijab $ \/ $ actes des congrès de la société française shakespeare | costume et déguisement dans le théâtre de shakespeare et de ses contemporains veiling an indian beauty: shakespeare and the hijab ( / ) richard wilson electronic version url: http://journals.openedition.org/shakespeare/ doi: . /shakespeare. issn: - publisher société française shakespeare printed version date of publication: december isbn: - - - electronic reference richard wilson, « veiling an indian beauty: shakespeare and the hijab ( / ) », actes des congrès de la société française shakespeare [online], | , online since december , connection on april . url : http://journals.openedition.org/shakespeare/ ; doi : . / shakespeare. © sfs http://journals.openedition.org http://journals.openedition.org http://journals.openedition.org/shakespeare/ costume et déguisement dans le théâtre de shakespeare et de ses contemporains a c t e s d u c o n g r è s organisé par la s o c i É t É f r a n Ç a i s e s h a k e s p e a r e les , et mars textes réunis par p i e r r e k a p i t a n i a k sous la direction de j e a n - m i c h e l d É p r a t s couverture : edouard lekston, w illiam en carton et ses habits à d écou p er , edlek@free.fr conception graphique et logo pierre kapitaniak © société française shakespeare institut du monde anglophone université de paris iii – sorbonne nouvelle rue de l’École de médecine paris www.societefrancaiseshakespeare.org tous droits de traduction, de reproduction et d’adaptation réservés pour tous les pays veilin g an i n d ian b eau ty: s h akes p ear e an d th e h ij ab rich ar d wilson th u s orn am en t is bu t th e gu ilèd sh or e to a m ost dan ger ou s sea, th e beau teou s scarf veilin g an in dian beau t y ; in a wor d, th e seem in g tru th wh ich cu n n in g tim es pu t on to en tr ap t h e wisest. the m ercha n t of ven ice (iii.ii. - ) assan io’s su spicion of th e ‘beau teou s scar f / veilin g an in dian beau ty’ as an object of both d an ger an d d esire appears to explain wh y in the m erchan t of ven ice h e prefers the casket of ‘m eagre lead’ to ‘pale an d com m on ’ silver or ‘gaudy gold.’ th is reverse epiph an y seem s to belon g to an or ien talist tr adition in wh ich th e muslim hijab altern ates as a sym bol of eith er eroticism or violen ce. devised, per h aps, for sh r ovetide, th e ‘casket scen e’ th ereby typifies car n ival aggr ession , with its th r ee guests n o lon ger gift-bearin g kin gs bu t r ecipien ts of th eir h ost’s discr im in ation . so bassan io’s r ejection of orn am en t plays to th e prejudice of portia’s test, wh ich en d s wh en ‘the curtain is draw n aside’ (sd: ; ), an d a tru e eu ropean beau ty is d isclosed with th e sam e eye-to-eye logic as th at with wh ich th e duke or der s sh ylock to ‘stan d befor e ou r face’ (iv.i. ). for all th eir love of m asks th ese ch r istian s lon g for th e face-to-face open n ess of a gift culture fast bein g d estroyed by th e self-in terest for wh ich a j ewish th e revels accoun ts r ecor d two per for m an ces of the m erchan t of ven ice dur in g sh r ovetide , th e secon d com m an ded by kin g j am es h im self. for th e car n ival con n ection s, see ch r is h assel, r en aissan ce dram a an d the en glish church year (lin coln : nebr aska un iversity press, ), pp. - . for a r ecen t discussion of th e am biguity of the veil as a sign of both er oticism an d violen ce, see faegheh sh ir azi, the veil un v eiled: the h ijab in m odern culture (gain esville: un iver sity of flor ida pr ess, ). but for a pr oposed em en dation of bassan io’s lin es, see lisa h opkin s, ‘“an in dian beauty?” a pr oposed em en dation to the m erchan t of ven ice,’ shak esp eare n ew sletter, ( ), . h opkin s ar gues for a pun ctuation of th e lin es as ‘th e beauteous scar f / veilin g an in dian ; beauty – in a wor d, / th e seem in g tr uth …’ but th is em en dation dim in ish es th e or ien talist ‘dark lady’ m etaphor . b rich ard wilson ban ker can be blam ed . discovered in sid e th e lead , ‘portia’s coun terfeit’ is th us a m in iature, with h air woven in ‘a golden m esh ,’ to publicise r ath er th an h ide wh at th is ‘fair est cr eatur e n or th ward bor n ’ claim s: ‘you see m e, lor d bassan io, wh er e i stan d, such as i am ’ (ii.i. ; iii.ii. , ). in m asques ladies of th e en glish cou r t wer e likewise d raped in veils of such tran sparen t gauze th eir id en tity was n ever in dou bt. yet h er e th e tr avel con ceit with wh ich bassan io en visages the hijab veilin g a ‘dan gerou s sea’ rem in ds u s h ow to play th is guessin g gam e h e h as availed h im self of a veil sim ilar to th at of th e in dian h ou r i, th e ‘over -weath er ’d r ibs an d r agged sails’ of h is in fatuated an ton io’s ‘scar fèd bar que,’ n ow ‘vailin g h er h igh top lower th an h er r ibs,’ as th e effem in ised m er ch an tm an is ‘h u gged an d em braced ’ on ly to be ‘ren t an d beggar ed by th e str u m pet win d’ (i.i. ; ii.vi. - ). an d wh at the sim ilar ity of sails to veils r eveals is th e r u b th at th is belly-dan cin g tr ade is all in favour of th e east. as ros ballaster explain s in fabulous orien ts, a ‘dark lad y’ d iscourse em erges at th is tim e in wh ich ‘th e veiled an d h idden wom an of th e seraglio’ em bod ies both th e superficial softn ess of in dian com m er ce an d its un d erlyin g d an ger, as th e en tire subcon tin en t com es to be un derstood as an em asculatin g h arem : ‘a kin d of abyss,’ in th e report of colbert’s agen t, ‘for a great part of the gold an d silver of th e world , wh ich fin d s m an y ways to en ter th ere, an d alm ost n on e to issu e h en ce.’ so if th e muslim veil sh ould be ren t in th is text, we are warn ed at the start, th at ‘d an ger ou s sea’ wou ld expose th ese ‘tr adefu l m er ch an ts’ to th e h idden violen ce of th e ‘dar k lady,’ an d reveal th e treach ery of th eir own secret d esires at a tim e wh en ‘in d ia’s econ om y is still m or e pr odu ctive… eu r ope’s lead is lim ited to sh ips… [an d] eu rope im ports asian m an u factu res, n ot th e reverse’: ros ballaster, fabulous orien ts: fiction s of the east in en glan d, - (oxfor d: o.u.p., ), p. - , , & - ; ‘letter to lord colber t,’ quoted p . cf. lisa j ar din e an d j er ry br otton , global in terests: r en aissan ce art betw een east an d w est (lon don : reaktion , ), p. - : ‘in th e fifteen th an d sixteen th cen tur ies, east an d west m e on m uch m or e equal term s… east m et west in str en uous an d con str uctive com petition .’ for th e politically ch ar ged sem iotics of silk, see also roze h en tschell, ‘tr eason ous textiles: foreign cloth an d th e con str uction of en glish n ess,’ jou rn al of m ediev al an d early m odern studies, ( ), - . ‘tr adeful m er ch an ts’: edm un d spen ser, am oretti, : ; ph ilip cur tin , cross-cultural trade in w orld h istory (cam br idge: c.u.p., ), p. . for th e con n ection between the ‘dark lady’ con ceit an d colon ial econ om ic en coun ter s, see also kim h all, thin gs of dark n ess: econ om ies of r ace an d gen der in early m od ern en glan d (ith aca: cor n ell un iver sity pr ess, ), p. - & - ; an d j oel fin em an n , shak esp eare’s perjur’d ey e (ber keley: un iver sity of califor n ia pr ess, ), p. . veiling an indian beauty sh ou ld i go to ch u r ch an d see th e h oly edifice of ston e an d n ot bet h in k m e str aigh t of dan ger ou s r ocks wh ich , tou ch in g bu t m y gen tle vessel’s side, wou ld scatter all h er spices on th e str eam , en r obe th e r oar in g water s with m y silks… (m er cha n t, i.i. - ) if th e ‘beau teou s’ veil of bassan io’s ‘dar k lady’ is som e ‘r ich scar f’ of silk (tem p est, iv.i. ), like th ose car r ied in th e belly of an ton io’s car avel, th e con fu sion it cau ses r epeats th e th r ill of illicit desire silk pr om pts th rough out th e plays, wh ere a sen suous relish for th e sh eer sh een of th e de luxe fabric cu es disgu st at th e ‘taffeta pu n k’ (all’s w ell, ii.ii. ), as opposed to ‘r u sset yeas, an d h on est ker sey n oes’ (lov e’s, v.ii. ), wh en ever ‘sim ple truth ’ is ‘abused / with silken , sly in sin uatin g’ lies (r ichard iii, i.iii. ). th is association of ‘chan geable taffeta’ (tw elfth, ii.iv. ) with ‘silken term s precise, / th ree-piled h yperboles’ (lov e’s, v.ii. ), was keyed to th e in flated pr ice of silk, n ot farm ed in en glan d u n til , wh en it cost shillin gs a yar d. bu t it was th e pliability of its soft fibr e th at also m ade it syn on ym ous with th e h arem , as ‘silk cou ld be spu n in to th r ead of var yin g th ickn ess, an d woven in to fabr ic of differ en t appearan ces, fr om fin est gauze (“cyprus”, “sarcen et”, used in lin in gs, an d “tiffan y”, u sed for pu ffs), to taffeta, wh ich was n ot so fin e, velvet, plush (a d eeper pile th an velvet), an d satin .’ not for n oth in g was sh akespeare’s fath er a glover, wh ose lin in gs supplied a m etaph or for lin guistic d uplicity – ‘a sen ten ce is but a ch everel glove to a good wit’ (tw elfth, iii.i. - ) – an d h is str atfor d fr ien d rich ard quin ey a dr aper sellin g taffeta, skein s of silk an d silk bu tton s, as h is texts flau n t appr eciation of silk’s ver satility in all its var ieties of ‘sad cypr ess’ per cy macquoid, ‘costum e,’ in shak esp eare’s en glan d: an accoun t of the life an d m an n ers of his ag e, ed. an on . ( vols., oxfor d: clar en don pr ess, ), vol. , p. . for m or e r ecen t h istor ies of fash ion in ear ly m oder n en glan d, see j oh n brewer an d roy por ter, con sum ption an d the w orld of goods (lon don : routledge, ), pp. - ; elizabeth kowaleski-wallace, con sum in g subjects: w om en , shop p in g, an busin ess in the eighteen th cen tury (new yor k: colum bia un iversity pr ess, ); bever ly lem ir e, dress, culture, an d com m erce: the en glish clothin g trade before the factory , - (basin gstoke: macm illan , ); len a or lin (ed.), m aterial lon don , ca. (ph iladelph ia: ph iladelph ia un iver sity press, ); dan iel roche, the culture of clothin g: dress an d fashion in the an cien r egim e, tr an s. j ean bir rell (cam br idge: c.u.p., ); su san vin cen t, dressin g the elite: clothes in early m odern en glan d (oxfor d: berg, ); an d lor n a weath er h ill, con sum er behav iour an d m aterial culture in britain - (lon don : routledge, ). for an im por tan t discussion of wom en an d con sum er society, see also kar en newm an , ‘city talk: wom en an d com m odification in j on son ’s ep icoen e,’ en glish literary h istory , ( ), - . liza picar d, elizabeth’s lon don : ev ery day life in elizabethan lon don (lon don : weiden feld & nicolson , ), p. . rich ard wilson (tw elfth, ii.iv. ), ‘green sarcen et’ (troilus, v.i. ), ‘flam e-colour ’d taffeta’ ( h en ry iv, i.ii. ), ‘peach -colour’d satin ,’ or ‘th ree-piled velvet’ (m easu re, i.ii. ; iv.iii. ). in d eed , with the lod ger ch ar les nich oll situ ates th e dr am atist at th e h ear t of lon don ’s silk in du str y, in th e r oom s h e r en ted in th e s fr om ch r istoph er moun tjoy in silver street, cripplegate, writin g above th e atelier wher e th e fren ch tirem aker operated th e spin n in g wh eels on wh ich filam en ts of silk were twisted in to th r ead kn own as ‘sleaves,’ wh ich were th en braided with wires upon oth er wh eels to form th e gold ‘tissue’ from wh ich rose ‘tires’ or ‘toys for th e h ead’ (w in ter’s, iv.iv. ). train ed in crécy, lon g a cen tr e like arr as for silk tapestr y, mou n tjoy was a m aster of the m yster y of wor kin g su ch ‘ven ice gold’ (tam in g , ii.i. ), th e ‘sweet com m ixtur e’ (lov e’s, v.ii. ) of ‘r ed an d m in gled dam ask’ (as you , iii.v. ) also n am ed from dam ascus, wh ere th e tech n iques of dam ascen e ‘cloth a’ gold… lac’d with silver ’ (ad o, iii.iv. ) h ad been d eveloped . it was in silver street th at sh akespeare d oubtless saw th e exor bitan t workm an sh ip of th e bizar r e ‘sh ip-tir e, th e tir e valian t, th e tir e of ven etian ad m ittan ce’ (w iv es, iii.iii. ), th at liter alised th e veiled lady as a sh ip of war. so, th ough nich oll peers in to th e moun tjoy h ouse to catch th e poet with mar ie as h is r eal ‘dar k lady,’ th e sem iotic wor ld of exotic textiles in wh ich h e asks u s to im agin e sh akespeare weavin g h is own texts to th e rh yth m of th e loom is sed uctive en ough to accoun t for h is h yper sen sitivity to th e su btle secr ecy of silk: in on e part of t h e sh op an app r en tice sits at a ben ch , dr awin g wir es of gilded silver th r ou gh die-h oles to m ake t h e fin e wir e su itable for gold th r ead. th ere ar e h am m er s an d r oller s to flatt en th e wir e in to st r ips r eady for spin n in g in to th r ead. in an oth er par t of th e sh op bu n dles of r aw silk ar e bein g separ ated in to ‘sleaves’. a th ird per son is wor kin g th e ‘twistin g wh eel’, tu r n in g th ose sleaves in to silk th r ead, an d silk t h r ead in to sparklin g ven ice gold … metal fu m es h an g in th e close air of th e wor ksh op, th e sm ell of glu es an d d yes… j u st ou tside… is a well-d r essed gen tlem an of m iddle age wh o m igh t be a m er ch an t or m er cer , bu t wh o is in fact th e tir em aker ’s lodger … h e is a sh adow in th e doorway, a footstep on th e stair s… [bu t] wh at h e sees an d h ear s is stored away… to be u sed in tu rn as r aw m aterial in th e m an u factu rin g of m etaph ors… in “sleep th at kn it s u p th e r avelled sleave of car e” (m acbeth, ii.ii. ). edgar fr ipp, master rich ar d quyn y bailiff of str atfor d-upon -avon an d fr ien d of william sh akespeare (oxford: o.u.p., ), pp. - . ch ar les nicholl, the lodger: shak esp eare on silv er street (lon don : allen lan e, ), p. - & . veiling an indian beauty ‘for h er own per son , / it beggared descr iption . sh e did lie / in h er pavilion – cloth of gold, of tissue’ (an ton y , ii.ii. - ): sh akespeare’s report of th e voyage of th e ultim ate ‘dark lad y’ ech oes marlowe, wh ose did o likewise h ad galleon s with ‘tacklin g m ade of riven gold .’ both are seen as ‘th e tailors of th e earth ; com fortin g’ th eir m en ‘th at wh en old robes are worn out th ere are m em bers to m ake n ew’ (i.ii. - ). but wh ereas th e queen of carth age boasted ‘sails of fold ed lawn ,’ th e egyptian surpasses lin en with d yed ‘purple sails’ of ‘silken tackle’ wh ich swell with ‘tou ch es of th ose flower -soft h an ds’ ( ; ). a wh ole cr isis in eu r opean textile pr odu ction lies beh in d th is switch from wool to silk as th e gold stan dard of econ om ic prowess, a r evolution mar lowe r egistered with h is j ew of malta’s ‘ar gosy fr om alexan d ria… lad en with rich es an d exceed in g store / of persian silks.’ an d fern an d brau del provided a global con text for th is am biguou s n exu s of sails an d veils swirlin g abou t a belligeren t ‘in dian beau ty’ wh en h e n oted h ow in th e s alm ost ‘ever y sin gle letter fr om ven etian m er ch an ts car r ied som e r efer en ce to silk,’ an d in ter pr eted th is fixation as an in d ex of the in security when th e value of bulk good s like en glish lead, tin an d woollen textiles exported east was sh am ed by th at of th e silk, ch in tz an d oth er ligh t fabr ics im por ted in r etu r n . th us, th ere was ‘a sort of super-dem an d’ as ‘th e r ich for sook gold an d silver for silk, wh ich as it becam e available to m ore people em erged as a sym bol of social m obility’ for a n ew con su m er age. with th e m ass m ar ketin g of in dian , per sian an d ch in ese silks, braud el recoun ted , ‘qu ick ch an ges in fash ion cr eated ar tificial bu t im per ative “n eeds” wh ich m igh t van ish over n igh t on ly to m ake way for oth er equ ally fr ivolou s passion s,’ for wh ile ‘people still spu n an d wove at h om e,’ th e su d d en availability of silk m ean t th at ‘it was n ow fash ion an d th e lu xu ry trad e th at d ictated d em an d .’ eu ropean govern m en ts legislated ch r istopher mar lowe, dido queen of carthage, , , - , in christop her m arlow e: the com p lete play s, ed. fr an k rom an y an d rober t lin dsey (lon don : pen guin , ), p. - . for im agery of re-cloth in g in dido queen of carthage, see rich ar d wilson , ‘tragedy, patr on age, an d power ,’ in patr ick ch en ey (ed.), the cam bridge com p an ion to christop her m arlow e (cam br idge: c.u.p., ), p. - . ch r istopher mar lowe, the j ew of m alta, , , - ; - , ibid. p. & . fer n an d br audel, the m editerran ean in the age of philip ii, tr an s. siân reyn olds (lon don : h arper collin s, ), p. . for the lon don en d of th is tr an scon tin en tal tr affic, see in par ticular g.d. ram say, ‘the un doin g of th e italian mer can tile colon y in sixteen th cen tur y lon don ,’ in n.b. h ar te an d k.g. pon tin g (eds.), textile h istory an d econ om ic h istory : essay s in hon our of m iss j ulia de lacy m an n (man ch ester : man ch ester un iver sity press, ), p. - , esp. p. . rich ard wilson to pr otect th eir textile in du str ies fr om th is in vasion , br audel r elated, ‘but all in vain . noth in g wor ked,’ n ot th e ban n in g of all asian silks fr om en glan d in , n or th e pr ize of liv res pu t u p by par is cloth ier s ‘to strip an y wom an wearin g in d ian fabrics’ n aked in th e street, or else to dr ess pr ostitu tes in in dian silks an d th en u n dr ess th em as exam ples. for wh ile defen der s of th e su m ptu ar y laws like stu bbes th un d ered th at ‘im puden t in solven cy is n ow grown th at everyon e, th ou gh ver y poor […] will n ot stick to h ave silk,’ th e in satiable eu r opean dem an d for its soft, sleek, sh im m er in g tissu e en su r ed silk becam e wh at bassan io m akes it, an d tr oilu s sh ows wh en h e r em in ds th e trojan s th eir ‘breath bellied h is sails’ wh en par is stole h elen , an d ‘we turn n ot back th e silks upon th e m erch an t / wh en we h ave spoiled th em ’ (troilus, ii.ii. - ), th e super lative exam ple of th e object wh ich gen er ates its own d esir e: kate, eat apace; an d n ow, m y h on ey love, will we r etu r n u n to m y fath er ’s h ou se, an d r evel it as br avely as th e best, with silken coat s, an d caps, an d golden rin gs, with r u ffs, an d cu ffs, an d far t h in gales, an d t h in gs, with scarves, an d fan s, an d double ch an ge of br aver y, with am ber br acelet s, beads, an d all th is kn avery. wh at, h ast th ou din ed? th e tailor stays t h y leisu r e, to d eck th y bod y with h is ru fflin g treasu r e. (the ta m in g of t he shrew , iv.iii. - ) in im p erson ation s, h is stu dy of cr oss-dr essin g, steph en orgel n otes th e fetish allu r e of fem ale apparel for elizabeth an m ales, th eir alm ost lacan ian awaren ess of th e ten den cy of ‘th e im agin ation of a desir able th in g to stir u p th e desir e.’ an d fem in ists n otice h ow, in episodes such as petruch io’s cruel fort / da gam e with kate’s tr ou sseau, wh ere h e scor n s h er ch oice of h at in kitch en ter m s as ‘a custar d coffin , a bau ble, a silken pie’ ( ), sh akespeare’s wom en sh ift from bein g prod ucers or con sum ers of textiles to bein g id en tified with th e cloth itself, a r eification testifyin g h ow ‘in ear ly m oder n en glan d it is th e fer n an d br audel, the w heels of com m erce: civ ilization an d cap italism , th- th cen tury , tr an s. siân reyn olds (lon don : collin s, ), p. . stephen orgel, im p erson ation s: the p erform an ce of gen der in shak esp eare’s en glan d (cam br idge: c.u.p., ), p. - ; ‘stir up th e desir e’: j oh n rain oldes, the ov erthrow of stage p lay s (lon don : ), p. . veiling an indian beauty m ater ial of su bjectivity itself.’ mar in a typifies th em , weavin g ‘sleided silk’ so ad roitly ‘h er in kle, silk, twin with th e r ubied ch er ry’ (pericles, : ; : ). th u s, as bassan io’s er otic object slides fr om th e con cealed face to its coverin g veil, th e ‘in d ian beau ty’ ven etian s crave, h is travail im ager y in sists, is th e car go of ‘silks’ an d ‘spices’ th eir ‘argosies with por tly sail’ deliver fr om th e ‘dan ger ous’ east (m erchan t, i.i. - ). clearly, sh akespeare ‘laugh ed to see th e sails con ceive / an d grow big- bellied with th e wan ton win d ,’ wh en som e freigh ter blown by th e ‘spicèd in dian air ’ tr avelled westwar d ‘fr om a voyage, r ich with m erch an d ise.’ th ere is a con n ection from th e latin v elum retain ed in th e fren ch v oile an d v oila, between v eil an d sa il as opaqu e an d open m em br an es, that en acts, h élèn e cixou s an d j acqu es der r ida su ggest in veils, th e in fin ite recession of veil an d valu e, travail an d travel, an d self an d silk: soi an d soie. th ere can be n o en d in th is serial h om on ym y to th e pen elopean labou r of ‘u n veilin g as veilin g.’ bu t in h is dan ce of veils set in the capital of carn ival sh akespeare ap pears to fret over th e travailin g sailcloth as a figure ‘markin g th e em bar kèd trad ers on the flood’ (dream , ii.i. - ) as em asculated by th eir veiled com m erce with mu slim s an d j ews, an d to be alerted by th e liken ess of th eir vessel’s ‘bellied sails’ (troilu s, ii.ii. ) to th e islam ic hijab to won der wh o in th e en d will prevail: th ose of oth er faith s wh o m odestly r efu se to ‘th r u st th eir h ead in to th e public str eet / to gaze on ch r istian fools with var n ish ed faces’ (m erchan t, ii.v. ), or th ese cr oss-dr essed clown s wh o h ar ass str an ger s with th eir m asks. so, with h is ‘wisest’ in vestor s ‘tr apped’ by th eir cir cuit of veiled in dian tr an saction s, an d th e bon ds of paper cr edit r equir ed to sustain it, sh akespeare appears to in tu it wh at patr icia fu m er ton an alyses in h er essay ‘th e veil of topicality,’ th at in m asques such as portia’s alludin g to th is ‘stran ge body’ of overseas trad e, ren aissan ce th eatre was posin g the cr u cial qu estion for the private eu ropean self as it en tered th e global m arket of available id en tities an d d an gerous d esires: ‘th e m aterial of subjectivity’: edith sn ook, ‘the greatn ess in good cloth es: fash ion in g subjectivity in mary wroth’s uran ia an d margaret spen cer’s accoun t book (bl. add. ms ),’ the sev en teen th cen tury , ( ), - , h er e . for th e ‘silen cin g’ of wom en in th is r eification , see susan fr ye, ‘stagin g wom en ’s relation s to textiles in othello an d cy m belin e,’ in peter erickson an d clark h ulse (eds.), early m odern visual culture: r ep resen tation , r ace, an d em p ire in r en aissan ce en glan d (ph iladelph ia: un iversity of pen n sylvan ia pr ess, ), pp. - . j acques der r ida, ‘a silkwor m of on e’s own ,’ in h élèn e cixous an d j acques derr ida, veils, tr an s. geoffrey ben n in gton (stan for d: stan for d un iver sity pr ess, ), p. & . rich ard wilson h ow to d ress in orn am en ts th e foreign trad e an d bou r geois bar barou sn ess in wh ich it was in volved so as to su stain th e fiction of gift cu ltu re wh ile allowin g bu sin ess t o con tin u e as u su al? h ow, th at is, to dr ess u p can n ibals an d ban ker s… so as to m ask t h e fact t h at th e “private” self was th e em bodim en t of su ch greed y con su m ption ? ‘nay, wh at are you , sir? o im m ortal god s, o fin e villain , a silken d ou blet, a velvet h ose, a scarlet cloak, an d a copin tan k h at’: th ou gh h is fath er is ‘a sailm aker in ber gam o,’ in h is silken gar b tr an io im agin es he passes for a gen tlem an (shrew , v.i. - ). as th eir own in vestm en t becom es global, sh akespeare’s plays are alive to th e reversal in world tr ad e th at disorien ts en glish gift culture in such ways, wh en th e export econ om y gr ou n ded in eu r opean dem an d for en glish wool is in ver ted in to an im por t econ om y fu elled by en glish con su m ption of ‘orn am en tal’ luxuries from asia. secreted by worm s, silk is th us m eton ym ic in th ese texts of th e represen tation al cr isis as ‘steel grows soft as th e par asite’s silk’ (coriolan us, i.ix. ). for in th is pan ic about sem blan ce an d su bstitu tion ser icu ltu r e is tr u ly th e m edium of a serial betrayal. so wh ile th e am bassadors at th e paradigm field of th e cloth of gold ‘make britain in dia’ in th eir silks, ‘th e cloth iers… put off / th e spin sters, carders, fullers, weavers, wh o… in d esperate m an n er… are all in u pr oar ’ (h en ry viii, i.i. ; i.ii. - ); an d wh at en rages th e cloth ier j ack cad e are ‘silken -coated slaves’ at cou rt ( h en ry vi, iv.ii. ). poin s’s vice is th erefore m easured in ‘peach colour ed ’ silk stockin gs; an d h al’s by ‘n ew silk an d old sack’ ( h en ry iv, i.ii. ; ii.ii. ), un til h e leaves ‘silken dallian ce in th e war dr obe’ to r aise ‘silken str eam ers’ (h en ry v, pro.ii. ; pr o.iii. ) again st th e fren ch , th em selves led by a ‘cocker ed silken wan ton ’ (john , v.ii. ). likewise, tim on ’s flatter er s ‘wear silk, dr in k win e, lie soft’ (tim on , iv.iii. ), as cym belin e’s fops ar e ‘r u stlin g in u n paid silk’ (cy m belin e, iii.iii. ). an d for an tiph olus of syracuse th e h eigh t of orien tal devilry is wh en ‘a tailor called m e in h is sh op, / an d sh owed m e silks’ (com edy , iv.iii. ). yet by th e tim e of the w in ter’s tale th e in ven tory of au tolycu s, th e pedlar who swam ps th e sh eep-shearin g fair with im ported ‘lesser lin en ’ like ‘in kles, caddises, cam br ics, r ibbon s of all colour s,’ wr istban ds, an d ‘golden coifs an d stom ach er s,’ r egister s th e d ram atist’s own awaren ess n ot on ly of th e com m odity fetish ism h istor ian s call ‘th e gr eat recloth in g’ – th e patr icia fum er ton , cultur al aesth etics: ren aissan ce liter atur e an d th e pr actice of social or n am en t (ch icago: ch icago un iver sity pr ess, ), p. . veiling an indian beauty ‘bon d age of certain ribbon s an d gloves’ in a fash ion system wh ere ‘you would th in k a sm ock a sh e-an gel,’ an d th ey wear ‘plackets wh ere th ey sh ould bear th eir faces’ (iv.iv. - ; - ) – but of th e futility of fen cin g en glan d’s wool com m un ities fr om th e global m ar ket, given th e u n iversal availability of th e n ew textiles sh ipped fr om ben gal, ceylon , madras or persia by ‘the m iracle of lon g-distan ce trade.’ ‘my tr affic is sh eets,’ leer s th is ‘master sm ooth , th e silk m an ’ ( h en ry iv, ii.i. ), adver tisin g h is por n ogr aph ic ch ap books, m ade of coar se woollen beddin g, as well as th e lu xu r y ‘wh ite sh eet bleach in g on th e h ed ge’ th is cuckoo steals or sullies in return . but th e ‘fan tastical’ taste for m od ish orien tal ‘en fold in gs’ h e passes on to h is cou n tr y cu stom er s to h ave th em refash ion th em selves as ‘gen tlem en born ’ is as m uch a m etr opolitan m akeover in this r ag-to-r ich es tale of ser ial redr essin g as th e sexu al availability h e proclaim s: will you bu y an y tape, or lace for your cape, my dain t y du ck, m y dear-a? an y silk, an y t h r ead, an y toys for you r h ead of th e n ew’st an d fin ’st wear-a?’ (the w in ter’s ta le, iv.iv. ) ‘if you bargain with mr sh akespeare, or receive m on ey th erefore, brin g your m on ey h om e if you m ay. i see h ow kn it stockin gs be sold ; th ere is great buyin g of th em at evesh am ’: th e on ly survivin g letters n am in g sh akespeare place h im in th e th ick of th e mid lan d garm en t trad e, as a backer of qu in ey in a d eal to m ake a killin g in tr adition al ‘kn it h osin gs.’ yet, like th e itin eran t ped lar wh o ‘wore th ree-pile’ velvet suits to serve prin ce florizel (iv.iii. ; iv.iv. ; v.ii. ); or in d eed the d ram atist h im self, issued four an d a h alf yards of scar let cloth by th e master of th e wardrobe to parade as a groom of th e ch am ber befor e kin g j am es; h is actors acqu ired th eir ‘cu t-rate mar garet spu ffor d, the great r eclothin g of r ural en glan d: petty chapm en an d the w ares in the sev en teen th cen tury (lon don : h am bledon pr ess, ), esp. pp. - ; ‘m ir acle of over seas tr ade’: br au del, op. cit. (n ote ), pp. - ; for pen etration of r u r al en glan d, see p. - ; cf. walter coh en , ‘th e un discover ed coun tr y: shakespeare an d m er can tile geogr aph y,’ in j ean h oward an d scott sh er show (ed s.), m arxist shak esp eares (lon don ; routledge, ), p. . abr ah am stur ley to rich ar d quin ey, october , rpr . in e.k. ch am ber s, w illiam shak esp eare: a study of facts an d problem s ( vols., oxfor d: clar en don pr ess, ), vol. , p. - . rich ard wilson war dr obe’ of silk fabr ics, we are told, secon d-h an d fr om th e cou r t. th is m ean t ‘th e players appeared in cloth es th at m igh t actu ally h ave belon ged to m em bers of th e aud ien ce;’ bu t an n e j on es an d peter stallybrass dedu ce th at by re-cyclin g h an d-down s th e stage also becam e a catwalk for cr owds to copy, a th eor y su bstan tiated wh en th e com m on er s elbow in to ju liu s caesar in ‘best apparel’ (i.i. ). sh akespear e’s ear ly plays tu rn on cast-offs fittin g ‘as if th e gar m en t h ad been m ean t for m e,’ as j u lia’s says (tw o gen ts, iv.iv. ). but h is later plays am plify the elite alarm over th e self-fash ion in g available wh en , as stu bbes fu m ed, ‘all per son s dr ess in discr im in ately in silks, velvets, satin s, dam asks, an d taffetas,’ as th ey also ech o th e actors’ an xiety th at ‘our stran ge garm en ts cleave n ot to th eir m ould .’ th e lin k between usurpation an d th e upstart wh ose expen sive borrowed cloth es ‘h an g loose abou t h im like a gian t’s robe / upon a d warfish th ief’ (m acbeth, i.iii. ; v.ii. - ) is clin ch ed in the tem p est, wh ere caliban ’s r ebellion en ds in a ‘fr ipper y’ or secon d-h an d shop, befor e prospero h im self d isown s as ‘trum pery’ th e ‘rich garm en ts, lin en s, stu ffs,’ th at ar e th e em blem s of h is power (i.ii. ; iv.i. ; ]. so, of in stan ces in sh akespeare of th e word ‘garm en t,’ are in h is j acobean texts, with in cy m belin e alon e, th e quick-ch an ge cross- dressed dram a th at, as stallybrass sh ows, qu estion s m ore th an an y oth er th e fetish izin g of ‘sen seless lin en ’ in a fash ion system th at ju d ges a m an by ‘h is m ean ’st gar m en t’ (i.iii. ; ii.iii. ). ‘i do n ot like th e fash ion of your garm en ts,’ lear objects: ‘you will say th ey are persian ; but let them be ch an ged.’ poor tom r aves again st ‘the r u stlin g of silks’ h im self. bu t th e m ad kin g’s an swer to ‘gor geou s’ or ien tal ‘soph istication ’ is to ‘u n bu tton ’ h is ‘len d in gs’ an d strip even ‘looped an d win dowed r aggedn ess’ down to ‘bar e an d u n accom m odated’ tr u th , so th at ‘th ou owest th e wor m n o silk’ (lear, ii.iv. ; iii.iv. - ; sam uel sch oen baum , w illiam shak esp eare a docum en tary life (oxfor d: o.u.p., ), p. ; stephen green blatt, ‘reson an ce an d won der,’ in learn in g to curse: essay s in early m odern culture (lon don : routledge, ), p. . stephen green blatt, shak esp earean n egotiation s: the circulation of social en ergy in r en aissan ce en glan d (oxfor d: claren don press, ), p. ; an n e j on es an d peter stallybr ass, r en aissan ce clothes an d the m aterials of m em ory (cam br idge: c.u.p., ). ph ilip stubbes, quoted in macquoid, op. cit. (n ote ), p. . peter stallybr ass, ‘wor n wor lds: cloth es an d iden tity on th e ren aissan ce stage,’ in margreta de gr azia, maureen quilligan an d peter stallybr ass (eds.), su bject an d object in r en aissan ce culture (cam br idge: c.u.p., ), p. - . for th e acquisition of cler ical vestm en ts by actors, see also steph en gr een blatt, op . cit. (n ote ), p. - . veiling an indian beauty iii.vi. ). ch r istoph er h ill th ough t th e qu aker s wh o str eaked star k n aked th r ough lon don str eets in th e s wer e in spir ed by th e n u d ism of kin g lear. bu t ‘th e pedlar ’s silken tr easu r y’ (w in ter, iv.iv. ] also su pplies th e solu tion en glish con sum ers preferred to su ch an apocalyptic divestm en t, wh ich was to flau n t th e availability of n ew textiles an d fr on t pr ivate desir es with th e pu blic face of fash ion itself: lawn as wh ite as dr iven sn ow, cyp ress black as e’er was crow, gloves as sweet as d am ask r oses, masks for faces, an d for n oses. (the w in ter’s ta le, iv.iv. - ) ‘masks for faces, an d for n oses’: sh akespeare’s ‘cloth -d riven th eatr e’ is qu ick to pick u p on th e strategy wher eby j acobean lon don er s separ ated pr ivate faces fr om public spaces, wh ich was to tr an spor t th e face m ask fr om fan cy dr ess to th e str eet. stowe sh u dder ed th at ‘wom en ’s m asks cam e in to en glan d abou t th e tim e of th e massacr e of par is;’ an d stu bbes listed am on g obstacles to social or der wom en r idin g with ‘visor s m ade of velvet wh erewith th ey cover all th eir faces, h avin g h oles m ad e in th em again st th eir eyes, wh erewith th ey look.’ bu t abou t the dr ive to see an d en joy withou t bein g seen to en joy took th e for m of silk ‘m asks for n oses,’ or black h alf- m asks kn own as vizards, cover in g on ly the upper face. in itially wor n as accessor ies to pr otect the com plexion , like th e ‘sun -expellin g m ask’ j u lia h as discar ded ‘sin ce sh e did n eglect h er lookin g-glass’ (tw o gen ts, iv.iv. ), vizar ds wer e defin ed by j oh n clevelan d in a poem , ‘th e kin g’s disgu ise,’ as articles ‘su ch as ladies wear / wh en th ey are veiled on purpose to be seen .’ wych er ley’s pin ch wife will th erefore m iss th e poin t wh en h e exclaim s such a visor ‘m akes people in qu isitive an d is as rid icu lou s a d isgu ise as a stage-beard ,’ sin ce for lear ’s suicidal m an ia for un dr essin g, see mar greta de gr azia, ‘the ideology of super fluous th in gs: kin g lear as per iod piece,’ in de gr azia, qu illigan an d stallybr ass, op. cit. (n ote ), p. - . ch r istopher h ill, the w orld turn ed up side dow n : r adical ideas durin g the en glish r ev olution (h ar m on dswor th : pen guin , ), p. . ‘cloth -driven theatre’: stallybr ass, op . cit (n ote ), p. . j oh n stowe quoted in m. ch an n in g lin th icum , costum e in the dram a of shak esp eare an d his con tem poraries (oxfor d: clar en don pr ess, ), p. - ; ph ilip stubbes, the an atom y of abuses (lon don : ), sig. g. . j oh n clevelan d, ‘th e kin g’s disguise,’ in the character of a lon don -diurn al: w ith sev eral select poem s (lon don : ), p. . rich ard wilson accor din g to ch r istoph h eyl in m asquerade an d iden tities, th is vir tual disgu ise was in fact design ed to be pen etrated: ‘it was still easy to recogn ise th e wearer… but th is m ust h ave been su fficien t to in tr odu ce n ew oppor tu n ities for playin g with an on ym ity,’ as th ese str eet m asks ‘both obscure th eir wearers an d attract atten tion .’ h eyl therefore views th e vogu e for h alf-m asks in th e s as a ver sion of in cogn ito r itu al, in wh ich , if you sign al you ar e in visible, people wh o recogn ise you are con strain ed to beh ave as if you are u n kn own , a perform an ce of suspen ded d isbelief wh ich can be com pared to th e th eatrical asid e. as h eyl r em ar ks, th e vizar d th us n egotiated a separ ation of public an d pr ivate sph er es by tu r n in g its wear er in to an ou tsider ‘in qu otes’: a h azardou s blu ff in th e face-to-face com m u n ity wh ere a stran ger was eith er h osted or expelled , but a kn owin g win k of m u tual com plicity in th e u r ban m etropolis ‘popu lated by people wh o wer e an d r em ain ed stran gers to on e an oth er,’ yet wh o were ‘m ore at ease with an on ym ity th an ever before.’ it fu n ction ed, th at is to say, accor din g to th e closet epistem ology defin ed by d.a. miller an d eve kosofsky sedgwick as th e pr actice wh er eby ‘opposition s between public/ pr ivate, in side/ outside, su bject/ object ar e established’ on th e tacit u n der stan din g th at ‘we kn ow per fectly well th at th e secr et is kn own … n on eth eless we m u st per sist… in guar din g it.’ so, ‘degree bein g vizard ed ,’ as sh akespeare’s ulysses bem oan s, ‘th e u n wor th iest sh ows as fair ly in th e m ask’ (troilu s, i.iii. - ). yet accor din g to th is an alysis, th e r elaxation of su ch sexu al, social, an d r eligiou s discr im in ation was pr ecisely the r ation ale of goin g ‘veiled on pur pose to be seen ’: th is appar en tly bizar re pattern of beh aviou r d em on strates th at th e privacy of st ran ger s or of p eople wh o n ow wan ted to be treated as stran ger s h ad becom e som et h in g to be resp ect ed… som eth in g wh ich wou ld h ave been regard ed as a m asqu erade in m ost oth er cou n tries was h er e bein g taken for gran ted as a par t of ever yday life. th is poin t s to a ch r istoph h eyl, ‘th e metam or ph osis of the mask in seven teen th - an d eigh teen th - cen tur y lon don ,’ in efr at tseëlon (ed.), m asquerade an d iden tities: essay s on gen der, sexuality an d m argin ality (lon don : routledge, ), p. - , her e pp. p. - & . th is im por tan t essay is repr in ted as ‘wh en th ey are veyl’d on pur pose to be seen ,’ in j oan n e en twh istle an d elizabeth wilson , body dressin g (oxfor d: ber g, ), p. - . d.a, miller, ‘secr et subjects, open secr ets,’ in the n ov el an d the police (ber keley: un iver sity of califor n ia pr ess, ), p. - , h ere pp. & . cf. eve kosofsky sedgwick, the ep istem ology of the closet (ber keley: un iver sity of califor n ia pr ess, ). veiling an indian beauty level of toler an ce in ur ban en glish societ y wh ich was in deed r em ar kable. ‘my visor is ph ilem on ’s r oof. with in th e h ouse is j ove,’ explain s don pedr o (m uch ado, ii.i. ), allud in g to th e th em e of th e kin g an d th e beggar th at provid ed a pretext for th e live-an d -let-live rule practised by ch arles ii, h is un cle ch r istian iv, an d h is gr an dfath er h en r i iv, in their escapad es of clown in g with th e poor. th e jest h in ts h ow even in the m asquerades of h is elizabeth an plays sh akespeare was attu n ed to th e com in g er a th at wou ld depen d n ot on r evelation an d un veilin g but on wh at th e span iar d don ar m ado lear n s is better th an war s of r eligion : a discr ete veil dr awn over ‘most m aculate th ough ts… m asked un der such colour s’ (lov e’s, i.ii. ). of cour se, n o on e was fooled by th e em peror’s n ew cloth es wh en th e merry mon arch wen t slu m m in g with nell gwyn , h is u n cle slipped u n h er ald ed in to lon don u n der th e pseu don ym of captain fr ed erickson , or h is gran d fath er, dr essed as a ‘wh istlin g’ doorm an , swept th e stage at the lou vr e to ‘m ake place for th e rascal players.’ h en ri took d ressin g d own so far louis xiii joked you could always tell h is fath er by h is sten ch . an d new h istor icism h as seen th r ough pr in ce h al’s ‘veil of wildn ess’ (h en ry v, i.i. ). th eir peasan t togs en act th e sam e fausse n aïv eté as th ose cou r t dresses ‘distr essed’ by ‘slash in g’ to look ‘n ew-fan gled ill’ (son n et ), an ar tfu l im postu r e petr u ch io dem olish es th e in stan t h e glim pses h is wife’s ball-gown : ‘o, m er cy god, wh at m asquin g stu ff is h er e?... h er e’s sn ip, an d n ip, an d cut, an d slish an d slash , / like to a scissor in a bar ber ’s sh op’ (tam in g, iv.iii. - ). yet an n e barton stresses h ow the popularity of th e ‘d isguised kin g’ gen re sym bolized th e fan tasy of ‘h ar m on y, good fellowsh ip, an d m utual un d er stan din g,’ wh ich was n ow replacin g face-to-face d issen t. an d wh en rosalin e m ocks ‘th at visor , th at su per flu ous case, / th at h id th e wor se an d h eyl, op . cit. (n ote ), p. & . j oh n gade, christian iv kin g of den m ark an d n orw ay : a picture of the sev en teen th cen tury (lon don : cassell, ), p. - ; leeds barroll, an n a of den m ark , queen of en glan d: a cultural biograp hy (ph iladelph ia: un iversity of pen n sylvan ia pr ess, ), p. ; sir rober t dallin gton ( ), quoted in desm on d sewar d, the first bourbon : h en ry iv, kin g of fran ce an d n av arre (lon don : con stable, ), p. . for th e slash in g vogue, wh ich peaked at th e tim e of shakespeare’s r om an ces, see aileen ribeir o, fashion an d fiction : dress in art an d literature in stuart en glan d (new h aven : yale un iversity pr ess, ), p. - . an n e bar ton , ‘th e kin g disguised: shakespeare’s h en ry v an d th e com ical h istor y,’ in essay s, m ain ly shak esp earean (cam bridge: c.u.p., ), p. . rich ard wilson sh owed th e better face,’ navar r e h as n o n eed to regret that ‘we were descr ied’ (lov e’s, v.ii. - ), for wh at th ese exch an ges likewise prove is th e im m u n ity gr an ted by th e in cogn ito r ule. fr an cois lar oque h as an alysed th e in terplay of ligh t an d d ark, vision an d blin d n ess, in th e m asqu er ade in r om eo an d ju liet. bu t ron ald kn owles poin ts out th at sh akespeare ch an ged th e story of h is lovers’ m eetin g, wh ich in th e sour ce occur s wh en ‘all did un m ask,’ becau se ‘for rom eo to h ave u m m asked wou ld h ave can celled th e h ospitality’ he exploits. th us it is eye to eye con tact wh ich h er e r em ain s taboo. as capulet affir m s wh en rom eo asks for ‘a case to put m y visage in ,’ an d don s ‘a visor for a visor’ to gatecrash th e ball, certain th at wh atever ‘cu riou s eye d oth quote d eform ity, / h ere are th e beetle brows sh all blush for m e’, th e virtue of goin g ‘covered with an an tic face’ for th is scopic regim e is n ot so m u ch th e r elease fr om iden tity it con fers on th e wearer, as th e blin d eye of obliviousn ess it dem an d s of th e viewer wh en ever som e spoilspor t tybalt gu esses the u n der lyin g tr u th (i.iv. - ; i.v. ): con ten t th ee, gen tle coz, leave h im alon e. a bears h im like a portly gen tlem an , an d, t ru th to say, ver on a br ags of h im to be a virtu ou s an d well-govern ed you th . i wou ld n ot for th e wealth of all th is town h er e in m y h ou se do h im disparagem en t. th er efor e be patien t, take n o n ote of h im . (r om eo a n d ju liet, i.v. - ) ‘to be in a m ask brin geth with it a certain liberty an d licen ce,’ th eorised castiglion e, ‘an d if h e were in a m ask an d th ough it were so all m en kn ew h im , it skilleth n ot.’ th e latin for m ask, p erson a, m ean t th at rom an law took a m ask at face v alue; an d th e idea of p erson a as p erson ality licen sed medieval m um m in g, wh ich assum ed a ‘vizard serveth to sm all effect wh en th e mum m er is kn own .’ bu t as meg twycr oss explain s in m ask s an d m ask in g, wh en duke ercole of fr an cois lar oque, ‘“cover ’d with an an tic face”: les m asques de la lum ière et de l’om bre dan s r om eo an d juliet,’ Études an glaises, ( ), - . ron ald kn owles, ‘car n ival an d death in r om eo an d juliet,’ in ron ald kn owles (ed.), shak esp eare an d carn iv al: after bak htin (basin gstoke: macm illan , ), p. ; geoffrey bullough , n arrativ e an d dram atic sources of shak espeare ( vols., lon don : routledge an d kegan paul, ), vol. , p. . baldassare castiglion e, the book of the courtier, tr an s. th om as h oby, ed. j .h . wh itfield (lon don : den t, ), p. - & . j acques yver, le prin tem p s d’iv er (par is: j ean ruelle, ), p. . veiling an indian beauty fer r ar a wen t guisin g at new year, lookin g for egg-figh ts an d erotic trysts, th e blur rin g of social categories d epen d ed on ‘th e presen ce of th e m asker ’s iden tity.’ now ‘th e im por tan ce of m askin g is, an d is ackn owled ged to be, a gam e’ of both give an d take. th is is th e kin d of m or ator ium wh ich gives h en ry viii its n er vou s r ictu s, wh en takin g th eir cu e fr om h is disgu ise as a sh eph er d at wolsey’s ball, h is victim s h u m ou r th e kin g by preten din g n ot to recogn ise th e ‘on e am on gst ’em ’ (i.iv. ) wh o h as power . so it is sign ifican t th at wh en ever sh akespeare in clu des su ch guisin g h e str etch es th e r ules of th is r ever se blin d-m an ’s bluff, like lon don ‘geezers’ takin g liberties by wearin g th eir vizard s ar oun d town . h e tests th e lim its of m u tu al toler ation : eith er to d estruction , as wh en rom eo an d j uliet fail to m ake th eir m asked en coun ter last, or to trium ph , as wh en th e prin cess an d h er lad ies put navar r e an d h is lor ds to su ch sh am e th at th ey m ust ‘ever but in visors sh ow th eir faces’ (lov e’s, v.ii. ). wh atever th e outcom e, th is ch an ge in focu s fr om display to con cealm en t r eflects a n ew developm en t in th e m ask-face relation , ‘d eliberately flirtin g with id en tity th at is teasin gly h idden bu t n ow n ever qu ite den ied.’ th e sh ift was fr om elizabeth ’s belief in prin ces ‘set on stages in th e sigh t an d view of all the world ,’ to j am es’s par an oia th at ‘all the beh olders’ were ‘ben t to look an d pry’ in to h is ‘secr etest dr ifts.’ an d so, even as th e court m asques were illu m in atin g the apollon ian per spective of spectacular power – wh en th e ‘deep tr u th abou t the m on ar ch y’ was un veiled, in or gel’s wor ds, as ‘th e fiction open ed outward to in clude th e wh ole cour t’ – sh akespeare was devisin g a con tr ar y for m of th eatr e, in wh ich a kin g’s d esir e to pass at n igh t veiled as ‘a com m on m an ’ is m atch ed, as th e soldier william s rem in d s kin g h arry, by a subject’s equally available n ew privilege to speak in pr ivate with ou t givin g offen ce: meg twycr oss an d su san car pen ter , m ask s an d m ask in g in m ediev al an d tudor en glan d (alder sh ot: ash gate, ), p. & - . ibid., p. . elizabeth i an d j am es vi an d i quoted in ch r istopher pye, ‘the sovereign , th e th eater, an d th e kin gdom e of darkn esse: h obbes an d the spectacle of power ,’ in stephen green blatt (ed.), r ep resen tin g the en glish r en aissan ce (ber keley: un iversity of califor n ia pr ess, ), p. . stephen orgel, the illusion of pow er: political theater in the en glish r en aissan ce (ber keley: un iversity of califor n ia press, ), p. . for th e apollon ian optic of th e cour t, see also mar tin j ay, dow n cast ey es: the den igration of vision in tw en tieth-cen tury fren ch thought (ber keley: un iver sity of califor n ia pr ess, ), pp. - . rich ard wilson your m ajesty cam e n ot like you rself. you appeared to m e but as a com m on m an . witn ess th e n igh t, you r gar m en ts, you r lowlin ess. an d wh at you r h igh n ess su ffered u n d er th at sh ap e i beseech you take it for you r own fau lt, an d n ot m in e for h ad you been as i took you for, i m ad e n o offen ce. (h en ry v, iv.viii. - ) ‘th e kin g’s first goin g abroad was privately to visit… h is h ou ses, for n atu r ally h e did n ot love to be looked on ’: when j am es i tour ed h is n ew capital ‘secr etly’ in , h is cover was blown by the ‘swar m s’ wh o sh ou ted ‘god save th e kin g’ to ‘h is gr eat offen ce,’ wh en ever he em erged in to th e street. yet the fact th at th e sly r u ler ’s peculiar desir e for pr ivacy was r espected by th ose in th e kn ow m ay be con n ected to th e virtual blin d spot wh ereby, as orgel poin ts out, th ere are h ardly an y ‘in stan ces in wh ich an yon e sees th rou gh a disgu ise in en glish ren aissan ce dram a,’ for on th is stage ‘cloth es really do m ake th e m an .’ th us, ‘th e soul of th is m an is in his cloth es,’ sn iffs th e old sn ob lafeu of par oles, th e ‘jack-an -apes with scarfs’ wh o ‘had th e wh ole th eor ic of war in th e kn ot of his scar f’ (all’s w ell, iii.v. ; iv.iii. ). ‘a sn ipped -taffeta fellow’ (iv.v. ), paroles’ iden tity really is boun d up with h is slash ed ‘scarves an d ban n erets’: ‘so, m y good win d ow of lattice,’ lafeu sn ipes, ‘i look th rough th ee’ (ii.iii. - ); an d ‘you ar e un don e, captain – all but you r scarf, th at h as a kn ot on ’t yet,’ h is captors sn eer. bu t on e of the twists wh ich m akes all’s w ell that en d s w ell so u n settlin g is par oles’ deter m in ation th at if a silk cr avat is his un doin g, ‘sim ply th e th in g i am / sh all m ake m e live.’ (iv.iv. - ). h is m uffler h as been so m uch a part of his old pan ach e, wh en h e does wh at iago despises an d wear s h is h ear t on h is sleeve (othello, i.i. ), th at after h e is blin dfolded with it the ‘saffron ’ dr ape (all’s w ell, iv.v. ) does seem a win dow in to h is sou l. ‘mu ffled’ (iv.iii. ) by th e scar f th at bin ds h im , th e m an of words is th erefore as m uch a victim as malvolio, in h is yellow stockin gs, of th e con strictin g bon d age of costu m e an d in teriority in th e ear ly m oder n fash ion system , th e tigh t fit between wh at j on es an d stallybr ass call ‘the su per ficiality of cloth in g an d the depth of th e su per ficial.’ th e cloth es, in th is view, m ake th e m an . yet wh en h e con fesses, ‘captain i’ll be n o m ore’ ( ), wh at we glim pse in paroles, as h e u n ties that stran gu latin g stock, is an in ward n ess n ot red u cible to sir roger wilbr aham an d ar th ur wilson , repr . in rober t ash ton , kin g j am es by h is con tem p oraries (lon don : h utch in son , ), p. - . stephen orgel, op. cit (n ote ), p. . j on es an d stallybrass, op . cit. (n ote ), p. . veiling an indian beauty such extern al m atrices, a person beh in d th e p erson a, or pr ivate face beh in d th e pu blic m ask; as if in th e wear in ess of all’s w ell that en d s w ell, th is pilgr im play about th e travails of travellin g, sh akespeare an ticipated der r ida’s bor edom with th e post-m od ern shibboleth of ‘truth as a h istory of veils’: voilà, fatigu ed like tru th , exh au st ed from kn owin g it, for too lon g, th at h istory of t h e veil, an d all t h e folds, explication s, com plicat ion s, explicitation s of its r evelation s an d un veilin gs… wh en th ey ar e to d o n ot on ly with open in g on to th is or th at bu t on to th e veil itself, a veil ben eath th e veil, like th e th in g itself to be bu ried … i am weary, weary, weary… of th is opposition t h at is n ot an op position , of r evelation as veilin g… fed u p w ith v ails a n d sails. in all’s w ell par oles’ loosen ed scar f seem s to flag h is ph ilosoph y th at ‘th ere’s place an d m ean s for every m an alive’ (iv.iv. ). likewise, in m easu re for m easu re, an d rew gurr writes, th e old tag th at ‘cu cu llu s n on facit m on achu m ’ – th e cowl d oes n ot m ake th e m on k – an d th at in adoptin g fran ciscan h abit th e du ke is ‘h on est in n oth in g bu t h is cloth es,’ ir on ises an gelo’s cr iticism of ‘th ese black m asks’ th at ‘proclaim an en sh ield beau ty ten tim es lou der / th an beauty cou ld be displayed’: th e visor s wor n by isabella an d marian a at th e close wh en lucio ‘p u lls off the friar’s hood an d discov ers the duk e’ (ii.iv. - ; v.i. ; sd, ). an gelo reads su ch a visor as an in citem en t, like th e m ask cr essida car r ies, sh e sm ir ks, ‘to defen d m y beauty’ (troilu s, i.ii. ), or th e ‘vir tuous visor’ th e m oth er of rich ard iii fear s h ides ‘deep vice’ (r ichard iii, ii.ii. ). bu t accor din g to gu r r th e separ ation of pu blic an d pr ivate sph er es in th is com edy depen ds on th e ver y am biguity wh en m asked wom en are, as posth um ous rails, eith er ‘for preservation cased , or sh am e’ (cy m belin e, v.v. ). h ere th e duke r ejects lu cio’s excu se th at h e spoke, like william s, ‘accor din g to th e trick’ wh en h e d efam ed h im in private. bu t a play that spares its h eroin e th e religious veil an d th e con ven t ‘isabella rule’ th at ‘if you speak, you m ust n ot sh ow you r face; / or if you sh ow you r face you m u st n ot speak,’ still en ds h avin g h er wait beh in d a visor un til th e duke offer s h er a ‘destin ed liver y’ as h is br ide (i.iv. ; ii.iv. ; v.i. ). th us h alf-m asks in m easu re for m easu re solve ‘th e pr oblem der r ida, op . cit. (n ote ), pp. - . see kath ar in e eisam an maus, in w ardn ess an d theater in the en glish r en aissan ce (ch icago: ch icago un iver sity pr ess, ), for a sustain ed cr itique of th e idea th at ‘the in dividual der ived sen se of th e self fr om exter n al m atr ices’ in sh akespearean en glan d (p. ). rich ard wilson of fin din g a m iddle way between fr eedom an d th e law,’ gur r con cludes, by sh ieldin g isabella fr om m ale ch ican er y: ‘disgu ise becom es a m ean s to everyon e’s un casin g,’ as ‘for th e wh ole fin ale (we see) her d ressed in a gen tlewom an ’s face m ask, with all th e freedom it offer ed.’ h oods, m asks, scar ves an d veils h ave r eceived too little atten tion in sh akespeare studies, gur r r em ar ks. yet wheth er or n ot the dr am atist was fam iliar with th e poor clares, or h ad a great-au n t isabel who becam e a pr ior ess, h is com edy does seem to ackn owled ge th e greco- rom an , byzan tin e, h in du , an d islam ic, as well as cath olic tradition th at respects th e veil as a sign of privilege an d power. m easu re for m easu re dates from a tim e wh en n un s like mary ward were ad justin g th e veil to varyin g d egrees of seclusion ; as oth ers, like th e ven etian n un s wh ose tran sparen t lace ‘attracted rather th an d eflected th e m ale gaze,’ were testin g ‘h ow perm eable con ven t walls, gr illes, an d door s could becom e.’ so in th is d r am a th e visor seem s, like th e m od ern hijab, a m ean s ‘to n egotiate a sph ere of social freed om .’ for on ce isabella is fitted ou t in on e of th e fash ion able silk h alf-m asks of the s h er en igm atic silen ce at th e close is keyed to th e epoch -m arkin g ph en om en on th e play explores, th e aversion to bein g studied by ‘m illion s of false eyes’ (iv.i. ) in th e n ew m etropolis where even th e kin g n ow claim ed ‘safe discr etion ’ for h is own pr ivate desir es an d ‘secr etest dr ifts’: i love t h e p eople, bu t do n ot like to stage m e to th eir eyes. th ough it do well, i do n ot r elish well th eir lou d applau se an d av es veh em en t; nor do i th in k th e m an of safe discr etion th at does affect it. (m easu re, i.i. - ) ‘am on g all par ts of th e wor ld, on ly en glan d h as n ot seen m asked beasts,’ r epor ted polydor e ver gil in th e s, ‘n or does it wan t to, because am on g th e en glish … th ere is capital pun ish m en t for an drew gurr, ‘m easure for m easu re’s h oods an d masks: the duke, isabella, an d liber ty,’ en glish literary r en aissan ce, ( ), - , h ere & - . j utta gisela sperlin g, con v en ts an d the body politic in late r en aissan ce ven ice (ch icago: ch icago un iver sity pr ess, ), p. . for mar y war d an d th e debate about the clausur a, see elizabeth rapley, the dév otes: w om en an d church in sev en teen th-cen tury fran ce (mon tr eal: mcgill-queen ’s un iver sity pr ess, ), p. - & - . j oh n bowen , w hy the fren ch don ’t lik e h eadscarv es: islam , the state, an d public sp here (pr in ceton : pr in ceton un iver sity pr ess, ), p. . veiling an indian beauty an yon e wh o wear s m asks.’ as an italian m igran t vergil h ad reason s for exaggeratin g a lon d on by-law again st ‘an y fein ed beard s, pain ted visor s, disfor m ed or colou r ed visages, in an y wise.’ bu t th e tu dor resistan ce to street m askin g, cu lm in atin g in a act ou tlawin g an y wh o ‘d isguised an d apparelled’ th em selves, or ‘covered th eir faces with visor s in su ch m an n er th at th ey sh ou ld n ot be kn own ,’ m akes it even m ore strikin g th at sh akespeare’s stage revolves arou n d th e kin d of ‘m ask’d an d vizarded’ im broglio th at brin gs the m erry w iv es of w in dsor to th e boil, with ‘vizor s’ for th e ch ild ren an d a silk veil for th e queen of th e fairies (iv.vi. ). th is is a th eatre wh ere, as ard en ’s ‘h oodies’ sh ow, wh en th ey dress like robin h ood an d ‘with a kin d of um ber sm ir ch ’ th eir faces, th ose wh o ‘ou tface it with th eir sem blan ces’ go ‘to liberty, an d n ot to ban ish m en t’ (as you , i.iii. - ). equally n oticeable, h owever , is th at with th e exception of sn u g’s ath en ian lion - m ask, fr om th e lady’s vizar d in wh ich flu te plays th isbe (dream , i.ii. ) to th e h igh waym en ’s visors on visors th at ‘in m ask’ h al an d poin s ( h en r y iv, i.ii. ), an d th e cagou les th at ‘m ask’ caesar’s assassin s (ju liu s, ii.i. - ), wh at in tr igues sh akespeare is n ot th e ‘absolu te m ask’ of an tiqu ity – th e p erson a wh ose ‘face is vizard -like, u n ch an gin g’ ( h en ry vi, i.iv. ) – but th e tan talizin g h alf-m ask wh ich , as barth es writes, always teases us with ‘th e th em e of th e secret’: as if in th is gam e th e m ask is always in vitin g falstaff’s r espon se: ‘by the lord, i kn ew ye as well as h e th at m ade ye’ ( h en ry iv, ii.v. ). as j ean -luc nan cy com m en ts, it is th e very fun ction of such a m ask to dr aw atten tion to itself, sin ce its par adox is a ‘self-sh owin g th at with dr aws. mon str ation occu r s in con cealm en t, an d fr om ou t of th at con cealm en t or d isappearan ce.’ th u s for h eyl, th e dialectical fu n ction of th e vizard , as both repellen t an d in vitation , is allied to th e ‘vir tu al disgu ise’ of th e liter ar y pseu don ym , as th e kin d of blin d eye wh ich was turn ed towards its open secret is essen tial to th e ‘strip-tease’ of m od ern au th orial an on ym ity. it m ay n ot th erefore be ch an ce th at in th e liter ar y text wh ich , fr om th e in stan t th e gh ost m ater ialises with its ‘beaver u p’ polydore vergil, begin n in gs an d discov eries: poly dore vergil’s ‘de in v en toribus rerum ’, tr an s. ben o weiss an d lou is për ez (nieu koop: de gr aaf, ), p. . pr oclam ation of , lon don : guildh all letter book i, folio r , quoted in twycross, op . cit. (n ote ), p. . rolan d bar th es, ‘th e face of garbo,’ in m y thologies, tr an s. an n ette laver s (lon don : vin tage, ), p. . j ean -luc nan cy, ‘th e masked im agin ation ,’ in the groun d of the im age, tr an s. j eff for t (new yor k: for dh am un iver sity press, ), p. . rich ard wilson (h am let, i.iii. ), dem on str ates m or e th an an y oth er th e ‘v isor effect,’ as der r ida ter m s it, by wh ich ‘we do n ot see wh o looks at u s,’ the occu lted sen se of secr ecy is associated thr ough out with wh at h eyl m ain tain s was a perception un ique to early m od ern lon d on , th e revolu tion ary recogn ition th at ‘d ress an d ou tward appearan ce were n o lon ger an in fallible gu ide to statu s’: ’tis n ot alon e m y in ky cloak, good m oth er , nor cu stom ar y su its of solem n black… th at can den ote m e tru ly… i h ave th at wit h in wh ich p asset h sh ow, th ese bu t t h e tr appin gs an d th e su its of woe (h am let, i.ii. - ) h am let’s ‘an tic disposition ’ (i.v. ) m igh t be seen as a su prem e in stan ce of the in ky textual cloak as fu n ction al equ ivalen t of th e j acobean black m ask: a ruse th at on ly ‘preten ds to disgu ise,’ an d ‘in stead of m akin g on e in con spicu ou s, m akes on looker s m or e in qu isitive.’ an d in secret shak esp eare i suggested such a ‘m asked im agin ation ’ relies on th e sam e closet subjectivity as pain tin gs by car avaggio, wh ere as leo ber san i an d ulysse dutoit obser ve, th e in vitation to in ter pr et is its own con cealm en t, for secr ecy is h er e per for m ed by a body ‘at on ce pr esen tin g an d with dr awin g’ its coy availability. th u s in caravaggio’s depiction s of boys the h om oer otic pose pr om otes u n r eadability in to a ‘wilfu l reticen ce, as if we were bein g solicited by a desir e deter m in ed to r em ain h idden .’ pu ttin g secrecy on d isp lay , car avaggio cr eates an in scr u tability like th at of th e face- m ask, sign allin g ‘don ’t ask, d on ’t tell’. it m ay n ot, th en , be ch an ce th at sh akespeare’s carn ival com ed y open s trailin g an ton io’s tease, ‘i kn ow n ot wh y i am so sad,’ a m ystification cr itics decod e, as th ey do th e pictu res, as n u d gin g towards a love that d are n ot speak its n am e. for un like m asques, wh ich un veil in th e d iscovery scen e th at, as orgel n otes, is th eir m ost fr agile poin t, by displacin g illicit desir es on to str an ger s, in th is play th e failu r e to scapegoat sh ylock m ean s th ose ‘visor effect’: j acques der r ida, sp ecters of m arx: the state of the debt, the w ork of m ou rn in g, an d the n ew in tern ation al, tr an s. peggy kam uf (lon don : routledge, ), p. ; h eyl, op . cit, (n ote ), p. . ibid. rich ar d wilson , secret shak esp eare: studies in theatre, religion , an d resistan ce (man ch ester: man ch ester un iversity pr ess, ), p. & ; leo ber san i an d ulysse dutoit, carav aggio’s secrets (cam br idge: mit pr ess, ), p. - . veiling an indian beauty ‘fools with var n ish ed faces’ can n ever u n m ask. so, wh ile bassan io th in ks ‘golden locks, / wh ich m akes su ch wan ton gam bols with the win d ,’ wigs as false as prosth etic beard s on boys, he calls h is own gam ble a quest for ‘golden fleece,’ an d to m arry gold fakes a ‘beard of h ercules’ h im self (i.ii. ; iii.ii. - ). h er e m asculin ity is fash ion ed, we see, like th e ‘livery’ lan celot exch an ges for d esertin g th e j ew, in distin ction to th e ‘little scr u bbed boy’ wh o ‘will n e’er wear h air on ’s face’ (ii.ii. ; v.i. - ). wh ile a h appy en din g to th is gam e of open secr ets also depen ds, as or gel obser ves, on th e ‘star tlin g peder astic fan tasy’ of girls ‘tu rn (in g) (in )to m en ’ (iii.v. ), sin ce th ese fem ales are in reality boys ‘th e seem in g truth ’ th erefore d isgu ises an even d eeper un truth : th at in th ese ‘cun n in g tim es’ of ‘m asked balls’ th ere will be m ask on m ask an d veil u pon veil. for th e last ‘in d ian beauty’ to be th e object of su ch passion ate d esir e in both m en an d wom en , we rem em ber, was in d eed oberon ’s m ysterious but ‘lovely… in d ian boy’ (dream , ii.i. ; iii.ii. ). in th is story bassan io preten ds to prefer por tia’s ‘golden m esh ’ to a ‘beau teou s scarf.’ yet in a reversal of h er own en tr y test h is br ide will cr oss-dr ess an d n am e h er self after balth azar , th e black magus wh o br in gs m yr r h fr om t h e east. so perh aps sh akespeare h eard h ow early m od ern eu ropean travellers to th e subcon tin en t wer e sur pr ised wh en the beguilin g figur e at a muslim wed d in g wh o em erged wearin g a gold en veil, an d with a silk h an d kerch ief coverin g th e m outh , turn ed out to be th e groom . ‘mislike m e n ot for m y com plexion , / th e sh adowed livery of th e bu r n ish ed su n ’ (ii.i. - ): as the on ly actu al mu slim in the m erchan t of ven ice morocco’s plea th at h is skin is yet an oth er m ask gain s a fur th er coatin g of path os if, as patr icia par ker in fer s, a ‘moor ish ’ or ‘in dian ’ com plexion is ‘sh adowed liver y’ in sh akespeare for th e ‘tribe’ of th e stephen orgel, the jon son ian m asque (cam br idge, mass.: h ar var d un iver sity pr ess, ), p. - . for bear ds as sign ifier s of m asculin ity, see will fr aser, ‘th e ren aissan ce bear d: masculin ity in ear ly moder n en glan d,’ r en aissan ce quarterly , ( ), - . but for th e pr osthetic con str uction of m asculin ity in false facial h air , see mark alber t j oh n ston , ‘pr osthetic absen ce in ben j on son ’s ep icoen e, the alchem ist, an d bartholom ew fair ,’ en glish literary r en aissan ce, ( ), - . stephen orgel, op. cit. (n ote ), p. . meer h assan ali, observ ation s on the m ussulm aun s of in dia descrip tiv e of their m an n ers, custom s, h abits an d r eligious op in ion s (lon don : h um pr ey milfor d & o.u.p., ; repr . ), p. : ‘the dress of th e br idegr oom is of gold-cloth , with an im m en se bun ch of silver tr im m in g th at falls over h is face, an d an swer s to th e purpose of a veil… an d to h is m outh h e keeps a red silk h an dker ch ief closely pressed to pr even t devils en ter in g.’ rich ard wilson m ar tyr ed fool th om as more: a rum ou r h eard wh en h e fin ds a m om en to m ori preserved as if in m yrrh in sid e th e gold en box. ‘th e black m an ,’ as mor e was called, claim ed descen t fr om th e n egr o doge mor o on wh om sh akespeare based othello, so m ou n ted an im paled blackam oor on h is cr est. mor occo’s death ’s-h ead looks, th en , to clin ch a n etwork of crypto-cath olic m u rm u rs run n in g, by way of latin pu n s on ‘th at black word d eath ’ (r om eo, iii.iii. ), fr om th e m ural con cealin g th isbe to th e sy cam ou r desdem on a lam en ts. wh at kn its th em all, parker proposes, is ovid ian m oralizin g on th e m oro: th e in d elible m ulberry d arken ed by th e blood of pyram us on w hich the silk w orm feed s. cr itics h ave lon g seen th e silk h an dker ch ief in othello as ‘m ore th an ju st a sym bol of m arriage,’ like ‘weddin g sh eets’ by ‘lu st’s blood spotted,’ for a play obsessed by ‘lawn , gown s, petticoats… caps,’ in wh ich th e h eroin e d ies because h er husban d can n ot trust th e in n ocen ce of ‘h er fan , h er gloves, h er m ask, n or n oth in g’ (iv.i. ; iv.ii. ; iv.iii. ; v.i. ). bu t n ow we are assu red th e reason s wh y ‘th er e’s m agic in th e web of it’ is th at ‘th e wor m s wer e hallowed th at d id breed th e silk’ after feastin g on th e ‘more tree’; th at it h as been ‘dyed in m um m y wh ich th e skilful / con ser ved of m aiden s’ h ear ts’ like th ose of th e tud or m artyrs; an d th at it was preserved by a r om an y (iii.iv. - ), t h is m or bid facecloth m or p h s in to a r elic beside veils like veron ica’s, as a m au dlin sign ifier of m ou rn in g for a proscribed religion , an d so join s th isbe’s m an tle – th e or igin al in dian veil, woven presum ably by bottom , th e weaver n am ed after a skein of silk – in a tr ue ser icultur e of veiled effu sion s of sh r ou ded gr ief. bein g ven etian s, th ese ‘ch ristian fools in varn ish ed faces’ are, of course, them selves all of ‘th e tribe of more,’ morocco h in ts, wh en he begs th em to ackn owledge ‘th is th in g of dar kn ess’ th eir s (tem p est, , , ). sh akespeare th us seem s to pred ict th e ‘qualified in toleran ce’ th at allowed th e en glish to ‘jud ge with out prejudice’ th e ‘agreem en t of the cu stom s of th e in dian s with th ose of th e j ews,’ in a n ascen t u n iver salism th at r elativised cath olics u n der cover of a sen se of patr icia par ker, ‘wh at’s in a nam e: mor e,’ sederi x i: r ev ista de la sociedad esp añ ola de estudios r en acen tistas in gleses (h uelva: un iversidad de h uelva publicacion es, ), - , esp. - ; wilson , op . cit. (n ote ), p. - , esp. p. . dym pn a callaghan , ‘lookin g well to lin en s: wom en an d cultur al pr oduction in othello an d sh akespeare’s en glan d,’ in h oward an d sh ersh ow, ibid, p. . for th isbe’s veil as a featur e of a babylon ian love stor y an d so th e pr ototype of th e hijab, see sh irazi, op .cit. (n ote ), p. - . veiling an indian beauty ‘an alogy, sh ared h istor y, an d sam en ess.’ as th is over determ in ed veil of topicality u n folds m oder n r eader s m igh t fin d su ch a ‘moor ish ’ subtext r ebar bative, just as mor occo assu m es we ‘m islike’ a colou r ed skin . th e violen t ch ar ism a of th e veil m ean s th at it always presen ts itself in th e form of such a ch allen ge. but as derr ida reflects, as h e pon der s th e war p an d woof of h is fr ayed j ewish tallith in h is essay ‘a silkwor m of on e’s own ,’ h owever m uch a softer age m igh t deplor e it, we will n ever get to ‘th e bottom less bottom ’ of the h istor y of violen ce wh ich colou r s such ‘a twist of r otten silk’ (coriolan us, v.vi. ): i wou ld like to sin g th e ver y solitar y softn ess of m y t allit h , soft n ess softer t h an softn ess, en tir ely sin gu lar … calm , acqu iescen t, a str an ger to an yth in g m au dlin , to effu sion or to path os, in a word to all “passion .” an d yet … before ever h avin g wor n a tallith or even dream ed of h avin g m y own , i cu ltivated … silkwor m s… in t ru th , th ey n eed ed lot s of m u lber ry, too m u ch , always too m u ch , t h ese voraciou s little cr eat u res… th is ph ilosop h y of n atu r e was for h im , for th e ch ild i was bu t t h at i r em ain still, n aiveté itself, dou btless, bu t also th e tim e of in fin ite appr en ticesh ip, t h e cu ltu re of th e r ag tr ad e… (so) th e wor d m u lber r y was n ever far fr om r ip en in g an d d yin g in h im , th e m u lber r y wh ose colou r h e war ded off like everyon e in th e fam ily, a wh ole h istor y an d war of r eligion s. ‘if you h ave tears, prepare to sh ed th em n ow. / you all d o kn ow th is m an tle’ (julius, iii.ii. ): j on es an d stallybr ass con sider all item s of ear ly m oder n cloth in g to be m ater ials of m em or y: a ‘secon d skin ’ wh ich ‘in scr ibed con flict’ an d h ad violen ce wr itten in to it, like th e n apkin em br oider ed with ‘con ceited ch aracters’ wh ich th e forlorn m aid wr in gs in ‘a lover ’s com plain t’: ‘laun d’r in g th e silken figur es in th e br in e.’ th us, wh en h ero’s weddin g-dress is com pared to th e in fam ou s gown of ‘cloth o’ gold, an d cu ts, an d laced with silver , set with pearls, d own sleeves, sid e sleeves, an d skir ts r ou n d u n der born e with a bluish tin sel,’ wor n by mar y tudor in h er r ole as ‘duch ess of milan ’ for h er weddin g to ph ilip of spain (m uch ado, iii.iv. - ), th e traces of j oh n tollan d, the agreem en t of the custom s of the ea st in d ian s w ith those of the jew s an d other an cien t peop le (lon don : ; repr. new yor k: ams press, ), p. ii; ‘qualified in toleran ce’: an ton y milton , ‘a qualified in toleran ce: th e lim its an d am biguities of early stuar t an ti-catholicism ,’ in arth ur marotti, catholicism an d an ti- catholicism in early m od ern en glish texts (basin gstoke: macm illan , ), p. . der r ida, op . cit. (n ote ), p. , & - . j on es an d stallybr ass, op . cit. (n ote ), p. ; ‘sh ared h istor y’: ballaster , op . cit. (n ote ), p. . rich ard wilson sectar ian violen ce cou ld n ot be m or e dar k. bu t sh akespeare’s texts str in g out a ver itable wash in g-lin e of su ch m n em on ic m an tles, scar ves, sh awls, sh r ou ds, veils, an d vestm en ts, all tear-soaked or m atted ‘in h ar m less blood’ ( h en ry vi, i.iv. ) – fr om t h e ‘dish clout’ ar m ado was ‘en join ed in rom e’ to wear ‘n ext to h is h ear t’ (lov e’s, v.ii. ), to th e popish ly ‘glisten in g apparel’ h u n g ou t by ar iel to tr ap m or on s m ou rn in g ‘mistress lin e’ h erself, th e m artyr an n e lin e (tem p est, sd. iv.i. ; ) – in wh ich , as celia exclaim s of orlan do’s bloodstain ed h an d kerch ief, th ere is ever ‘m ore in it’ (as you, iv.iii. ). sh akespear e kn ows th e m artyr will always h ave d evotees to ‘d ip th eir n apkin s in h is sacr ed blood’ (ju liu s, iii.ii. ). yet in episodes su ch as an ton y’s ter r or istic un veilin g of caesar’s sh r oud , with th e r evelation of th e ‘place,’ ‘r en t,’ an d ‘u n kin dest cu t’ wh ere ‘th e blood of caesar followed ,’ we are alerted to th e category con fusion of id olizin g ‘th e m an tle m u fflin g u p h is face’ as if it was ‘caesar ’s vestu r e’ th at was ‘wou n ded’ ( - ): th e ‘stron g m ad n ess in a silken th read ’ (ad o, v.i. ), for an age wh ich h as seen ‘n apkin s en ough ’ (m acbeth, ii.iii. ). so, th ough bian ca fails to ‘take ou t’ th e ‘wor k’ a ‘sybil... in h er pr oph etic fur y sewed’ in to th e egyptian veil (othello, iii.iv. - ; ; iv.i. ), green blatt is surely righ t to say th at sh akespeare’s plays are h au n ted by r eligiou s sign ifier s wh ich h ave been ‘em p tied ou t,’ if by th at evacuation we m ean th at th eir ‘proph etic fury’ h as been laun d ered in th e pacifyin g solu tion of theatr e itself. h is ch aracters d o in d eed in h abit ‘a worn world,’ clad in secon d-h an d cast-offs of th e war of religion s, wh ich h ave been fabricated in italy, from silk sh ipped out of afr ica, bough t in in dia with am erican gold. bu t as th e action of the tem p est su ggests, h is own wor k with veils an d sails seem s to be to wash ou t th e blood an d tears, so as to leave ‘on th eir su stain in g gar m en ts n ot a blem ish , / bu t fr esh er th an befor e’ (i.ii. - ): ou r gar m en ts bein g, as t h ey wer e, d ren ch ed in th e sea, h old n otwith stan din g th eir fr esh n ess an d glosses, bein g rat h er n ew-d yed th an stain ed wit h salt water […] as fr esh as wh en we pu t th em on fir st in afr ic, at th e m ar riage of th e kin g’s fair dau gh t er claribel to th e kin g of tu n is. (the tem p est, ii.i. - ) see wilson , op. cit. (n ote ), p. - . green blatt, op. cit. (n ote ), p. & . ‘wor n wor ld’: stallybrass, op. cit. (n ote ). veiling an indian beauty fr om moslem , to ch r istian , to th eatrical possession : ‘wh at is at stake in th e sh ift from th e old religion ’ to th eatre, asks green blatt, wh en ‘a bit of r ed cloth ’ like car din al wolsey’s silk ber r etta is r ecycled on a stage th at both ‘m ocks an d celebrates’ its violen t ch arism a? th e an swer , bassan io’s ‘in dian veil’ su ggests, is th e separ ation of pr ivate an d pu blic sph eres as a precon dition of racial, religiou s, sexual, an d artistic freed om s. ‘un seen to see th ose sh e feign would kn ow,’ th e ‘m asked lad y in th e pit’ at the playh ouse was h erself a con tributor to th is n ew coexisten ce, gu r r sh ows. an d th e ‘moor ish ’ h ier oglyph ics of a text like th e m asqu e of black n ess, acted by th e cath olic queen an n e in defian ce of th ose wh o th ou gh t black faces a ‘loath som e sigh t,’ con firm h ow aud ien ces would in d eed pen etrate sh akespeare’s m oral about h is dar k m ater ials as h e wove a tissue of ter r or an d toler ation out of a m ortal ‘th read of silk’ (dream , v.i. ). in episodes like the veilin g of th e ‘madon n a’ olivia, wh en th e ‘dar k lady’ covers up with h er m an tilla so ‘like a cloistress sh e will veiled walk,’ th ese d ram as d o seem to stress th e m orbid dan ger of an in teriority apt ‘to take dust’ like ‘mistr ess mall’s’ (or mar y’s) pictur e, cur tain ed in the r ecusan t h ouse (tw elfth, i.i. ; i.v. - ). th e poet’s own ‘m asked im agin ation ’ always h opes for som e gr an d u n veilin g, like th e d iscovery scen es th at pr osper o con tr ols: ‘th e fr in ged cur tain s of thin e eye advan ce / an d say wh at th ou seest yon ’ (tem p est, i.ii. - ). but in our pr esen t stan d- off, th is secretive sh akespeare assures us, th e question of th e hijab ‘veilin g an in d ian beau ty’ m u st rem ain on e of tru st – as alain bad iou sim ilarly reflects: ‘brech t says th at th e en d is with us wh en th e figures of oppression n o lon ger n eed m asks,’ bu t ‘it is n ecessar y to r eth in k th e relation between violen ce an d th e m ask… th e th eatrical m ask is a sym bol of a question erron eously d esign ated in th e cen tury of th e lie. th e question is better form ulated as follows: wh at is th e relation between th e passion for th e r eal an d th e n ecessity of sem blan ce?’ or green blatt, op. cit. (n ote ), p. - . j oh n lan e ( ) an d ‘t.m.’ (c. ), quoted in an dr ew gur r, play goin g in shak esp eare’s lon don (cam br idge: c.u.p., ), p. & . ‘very loath som e’: dudley carleton , cited in c.h . h erford, an d percy an d evelyn sim pson , ben j on son ( vols., oxfor d: clar en don pr ess, - ), vol. , p. . for an n e’s defian t ‘dram a of fem in in e blackn ess,’ see also soph ie tom lin son , ‘th eatr ical vibr an cy on th e car olin e cour t stage,’ in clar e mcman us (ed.), w om en an d culture at the courts of the stuart queen s (basin gstoke: palgrave, ), p. - . alain badiou, the cen tury , tr an s. alber to toscan o (cam br idge: polity pr ess, ), p. . rich ard wilson as der r ida decides at th e en d of h is essay on sails an d veils, th e secretion of th e silkworm , th is ‘slim e fr om slugs,’ is th e precious secret of th e secret itself: ‘wh at i app rop r iated for m yself… was t h e op er ation th r ou gh wh ich th e wor m it self secret ed it s secr etion . it secr eted it, th e secretion … it secr eted absolu t ely… th is little silen t fin ite life was doin g n oth in g oth er … t h an t h is: pr eparin g it self to h id e itself, likin g to h id e itself, with a view to com in g ou t an d losin g it self… wrappin g it self in wh it e n igh t . rich ar d wilson un iver sity of car diff der r ida, op . cit. (n ote ), p. - , ‘slim e fr om slu gs’: p. . pc .. review modeling regulatory networks to understand plant development: small is beautiful alistair m. middleton,a etienne farcot,b markus r. owen,c,d and teva vernouxe, a center for modeling and simulation in the biosciences and interdisciplinary center for scientific computing, university of heidelberg, heidelberg, germany b virtual plants inria team, université montpellier , montpellier cedex , france c centre for mathematical medicine and biology, school of mathematical sciences, university of nottingham, university park, nottingham ng rd, united kingdom d centre for plant integrative biology, university of nottingham, sutton bonington le rd, united kingdom e laboratoire de reproduction et développement des plantes, centre national de la recherche scientifique, institut national de la recherche agronomique, ecole normale supérieure de lyon, université lyon i, université de lyon, lyon cedex , france we now have unprecedented capability to generate large data sets on the myriad genes and molecular players that regulate plant development. networks of interactions between systems components can be derived from that data in various ways and can be used to develop mathematical models of various degrees of sophistication. here, we discuss why, in many cases, it is productive to focus on small networks. we provide a brief and accessible introduction to relevant mathematical and computational approaches to model regulatory networks and discuss examples of small network models that have helped generate new insights into plant biology (where small is beautiful), such as in circadian rhythms, hormone signaling, and tissue patterning. we conclude by outlining some of the key technical and modeling challenges for the future. introduction: analyzing gene regulatory networks to understand biological complexity plants are complex organisms that can adapt their morphology to suit environmental conditions. as for other organisms, their development is a continuous and dynamical process, in which large numbers of components interact at various scales, from genes and molecules to cells and tissues. until recently, plant scientists would study only a handful of these components at a time, and to make sense of their behavior, they would typically assume only a simple chain of cause and effect. in many cases, however, this will provide only a partial representation of the underlying complexity. in the last years, the analysis of plant systems (among others) has moved progressively toward moni- toring these elements in large numbers. this has been fueled in large part by the advent of -omics technologies, allowing one to follow thousands of genes or proteins simultaneously. in turn, this has forced biologists to envisage new ways of elucidating the underlying biological mechanisms. systems biology offers a powerful framework to analyze large, complex data sets, whereby the organism (or part thereof) is viewed as a set of entities interacting according to a particular set of rules, so that the properties of the organism emerge from these interactions. this vision holds at all scales and in particular at the genomic scale, with gene regulatory and signaling networks processing multiple cell-autonomous and non-cell-autonomous inputs to generate emergent cellular behaviors. these will give rise to emergent behaviors at the tissue scale. one of the key challenges then is to assemble the pertinent gene regulatory and signaling networks and to understand how they process signals to generate appropriate responses. the availability of large-scale data sets, however, has not eliminated the need for complementary smaller scale analyses. studies of whole-genome gene networks have led to the sug- gestion that these are composed of smaller and topologically distinct subnetworks (milo et al., ) that can be studied sep- arately from the rest of the network. on the other hand, even with the traditional reductionist approach, one rapidly finds that systems approaches are also required to deal with processes involving just a few genes/proteins that have been identified, for example, through classical genetics. indeed, many of the success stories in systems biology derive from such smaller scale studies, building up understanding of a process by working outwards from a key molecule of interest. examples of small-scale network studies have flourished in recent years. the aims of this review are to illustrate the importance of studying these networks in plants, to provide biologists an overview of mathematical approaches used for modeling them, and to illustrate how systems analysis of small networks can be used to generate biological knowledge, focusing more specifically on recent studies of gene regulatory and signaling networks involved in plant growth and development. dynamical modeling of gene regulatory networks before focusing on small networks, it is necessary to introduce mathematical concepts and definitions of dynamical models, address correspondence to teva.vernoux@ens-lyon.fr. www.plantcell.org/cgi/doi/ . /tpc. . the plant cell, vol. : – , october , www.plantcell.org ã american society of plant biologists. all rights reserved. mailto:teva.vernoux@ens-lyon.fr http://www.plantcell.org/cgi/doi/ . /tpc. . http://www.plantcell.org which allow addressing how a network behaves over time under various conditions. simple intuition about a complex system can indeed often be misleading, and models are es- sential to facilitate our understanding and clarify our as- sumptions. here, a model can be defined as a mathematical representation of a system, which can be used to test hypoth- eses, make predictions, and carry out in silico experiments (“what happens if.?”). models are always simplifications and, thus, invariably are incorrect. ideally, they should be improved in an iterative loop in association with experimental work, a point that we will discuss further below. when considering genes and signals within a complex network, there are methods to infer their topology. this has been the subject of other reviews (for example, see de smet and marchal, ; bassel et al., ; kholodenko et al., ) and will not be discussed here. what do we study with dynamical modeling? dynamical models predict how interactions between network components can lead to changes in the state of a system. the most basic process is for a system component to respond positively or negatively to some stimulus. however, develop- mental processes often require more complex responses, such as a switch between different cell fates, this being a common characteristic of developmental systems (for example, see middleton et al., ). there are many examples of bi- ological switches for which mathematical modeling has made a crucial contribution, including the lactose operon-inducible system (santillán and mackey, ) and the lysis-lysogeny decision by phage lambda (shea and ackers, ; santillán and mackey, ). in plants, it has recently been shown that a spatially distributed switch regulates root epidermis pat- terning (see below and figure ; savage et al., ). another typical complex dynamical behavior is an oscillator, such as the cell cycle (sha et al., ) and the circadian rhythm (discussed below; locke et al., ). more complex still is the coordination of these ingredients to make an organism, which for plants involves graded responses to stimuli and cell fate decisions (switches), coupled to regulation of the cell cycle (oscillators) and cell growth. note that there need not be a correlation between complex behavior and the complexity of a network; it is possible for quite simple networks to be- have in a highly complex manner, while extremely complex networks can behave, due to their specify topology, in a regular and tightly controlled way (csete and doyle, ; marr et al., ). given a dynamical model (of whatever size or complexity), it is of crucial interest to learn as much as possible about the model steady states (where all components of the network, for exam- ple, concentrations of various proteins or mrnas, are in equi- librium so that they do not change in time) and their stability (whether or not the system moves toward the steady state when given a small perturbation away from it) as determinants of system dynamics. these ideas can be visualized in terms of how a ball might move if placed on a smooth landscape (illustrated in figure a). if carefully balanced at the peak of a hill, the ball will stay there for all time. thus, this position can be thought of as a steady state of the system. however, if given a small perturbation away from the peak, it will move down the hill and not return. thus, this particular steady state is unstable. the bottom of a valley is also a steady state of the system. how- ever, in this case, if given a small push away, the ball will roll back. in this case, we can say the steady state is stable. analogously, in a model of a gene network, the system should return to a stable steady state if given a small perturbation away from it. this is particularly significant since biological systems are continually subjected to both internal and external perturbations. thus, stable steady states (as opposed to un- stable ones) are the only type of steady state to be attained in practice. other more complex long-term behavior can be ob- served in dynamical models, such as sustained oscillations (also known as a limit cycle). both stable steady states and stable limit cycles are examples of attractors. attractors can be understood, more generally, as a set of states toward which a system will evolve over time. each attractor can be reached by a certain set of initial states, called its basin of attraction (figure a). in the case where the system can have two stable steady states (e.g., two distinct valleys, in the case of figure a), it is referred to as bistable. the properties of the system (e. g., the number, type, and stability of attractors) can depend crucially on the parameter values of the model. if changing a particular parameter value results in a change in one of these properties, then we call this change a bifurcation. although initially not termed mathematically, it was suggested quite long ago (waddington, ; delbrück, ) that cell types cor- respond to attractors and that developmental processes cor- respond to different populations of cells entering one attraction basin or another (so the system has multiple steady states). this biological interpretation of the dynamics of regulatory networks is a key concept, independent of the mathematical formalism used to specify a particular model. the study of these various system properties (steady states, limit cycles, etc.) is often referred to as mathematical analysis in the liter- ature. mathematical frameworks to build dynamical models the systems mentioned above, along with their associated behaviors, are usually described in terms of dynamical models. here, we introduce the mathematical frameworks that can be used to build them. the state s of the model at time t is just the set of all the variables “x , x , ., xn” at time t: sðtÞ ¼ fx ðtÞ; x ðtÞ; . ; xnðtÞg; ð Þ which can be considered as a point in the (n-dimensional) state space of the system. in principle, the variables are measurable quantities, such as mrna, protein, or hormone concentrations (although these may be difficult, if not impossible, to obtain in practice using current experimental techniques). we would like to be able to understand the past and present and predict the future, based upon the interactions between the system com- ponents. if the state is changing with time t, then the model is dynamical, and the time-varying components of the state are the variables x (t), x (t), . . . , xn(t). the form of model we shall study is: systems approaches to regulatory networks sðt Þ ¼ fðsðt Þ; p ; p ; . ; pmÞ; t > t ð Þ where f is a function encoding our understanding of how the system components affect one another, and p , p ,., pm are model parameters. equation simply states that the future state of the system is some function of its past state (i.e., that the future is predictable). a trajectory of the system is then the set of future states given a particular initial state. the parameters are numerical values that encode information about the system and do not vary in time, such as the degradation rate of an mrna. a particular choice of parameter values can be thought of as a point in parameter space. the components [xi(t)] and inter- actions (encoded in f) can be inferred from a wide range of data sources, such as genetic and rna interference screens, mrna profiling, protein–protein interaction screens, and analysis of transcription factor binding. each has strengths and limitations, and integration of multiple data sources is important for reliably figure . introduction to dynamical models of small networks. (a) cartoon illustrating key properties of a dynamical model. (b) mass action model for the association and dissociation of two proteins. these can be written in terms of a chemical reaction scheme. the law of mass action dictates how the rate of formation and dissociation depend on the concentration of the reactants. from this an ode can be formulated. (c) a michaelis-menten model of gene expression. the model can be formulated by applying the law of mass action to the chemical reaction scheme depicted. tf, transcription factor. (d) the mutual inhibition feedback loop. both boolean- and ode-based models (right panel) are bistable (for certain parameter values) and have analogous steady states. however, in the boolean model, transitions between the states depend on which update method is used (cf. right panel and bottom panel). the plant cell inferring the interactions in a network (see bassel et al., in this issue). in gene-regulatory networks, where the state variables typically correspond to mrnas, proteins, and other molecules, each variable should be represented by a discrete quantity, an in- teger (e.g., the number of molecules), and changes in state are discrete events (namely, the creation or degradation of a mole- cule). if the amount of each component is sufficiently large, then its state can be approximated by a continuous variable that changes in time (e.g., concentration). this leads naturally to the use of ordinary differential equations (odes), defined by the rates of change of the system components, interpreted (in words) as: rate of change of mrna concentration ¼ transcription rate decay rate the use of odes is not computationally demanding and is very common within the plant systems biology literature. an- other type of model often used is based on boolean networks, in which the state variables are either off ( ) or on ( ), rather than numbers of molecules or concentrations. these are two types of models that represent the most common frameworks, and we describe them in greater detail below (the interested reader should see also the conclusion and future challenges section for a discussion on stochastic models). odes if we represent the network state s(t) as a continuous variable, then it has a well-defined rate of change. an ode model gives the rates of change of the variables xi(t) as functions of the state at that time: dxi dt ðtÞ ¼ fi �� xÆiæðtÞ � ; p ; p ; . ; pm � ; i ¼ ; ; . ; n ð Þ where {x(t)} is the set of variables that affect xi(t), and we write dxi(t)/dt to denote its rate of change. the functions fi encode the interactions between components (e.g., chemical reactions, transcriptional regulation, etc.) and are in general hard to deter- mine. in practice, however, models are often based on a small set of standard forms for fi (see later for examples), derived from the laws of physics and chemistry. for chemical reactions, an important concept for formulating fi is the law of mass action, which states that the rate of a chemical reaction is proportional to the product of the concentrations of the reactants. a simple example of this is illustrated in figure b, showing how an ode model for the binding and unbinding of two proteins can be formulated. given a set of reactions, it is relatively straightforward to write down the corresponding odes. for processes such as transcriptional regulation, commonly used forms can be derived by considering the binding and unbinding of transcription factors to dna. for example, figure c illustrates an activating tran- scription factor binding to dna to give a complex that leads to the production of mrna. by assuming transcription factor binding and unbinding is relatively fast compared with tran- scription, one can obtain the following expression for the rate of mrna production: d½p� dt ¼ vmax ½tf� k þ ½tf� ð Þ where [p] is the product (mrna) concentration, [tf] is the transcription factor concentration, and vmax and k are parameters derived from the rates of transcription factor binding and unbinding, and mrna formation. this is similar to the michaelis-menten equation for enzyme substrate reactions (alon, ) and is a natural form to use for transcriptional activation by a single tf. functions representing transcriptional repression can be derived in similar way, as can hill functions (increasing and decreasing) in the case where binding to dna is cooperative. more difficult is the problem of how to combine multiple transcriptional regulators (e.g., an activator and a repressor). three main approaches have been considered in the literature: phenomenological, extensions to the above michaelis-menten quasi–steady state approach, and a ther- modynamic approach (shea and ackers, ). however, in many cases, these all lead to the same or similar mathematical ex- pressions (bintu et al., a, b). what we have now are ode models for gene regulatory net- works whose variables are mrna and protein concentrations, with rates of change given in terms of mass action, functions representing transcriptional activation and repression, linear decay, and translation. model parameters include thresholds for transcriptional regulation; effective cooperativities; half-lives; rel- ative contributions of multiple transcriptional regulators; transfer rates (e.g., cytosol to cell surface); transformation rates (e.g., cleavage, phosphorylation); and binding. to illustrate this fur- ther, below we discuss the construction of an ode model for the auxin signaling and response network (figure a). boolean networks in the case of boolean networks, variables now represent the state of a gene and can either be or . the rules governing how the current state relates to the next one are encoded according to boolean logic and are intended to reflect the topology of the gene or signaling network. in these boolean rules, the activation of a component (e.g., a gene) is represented by an instanta- neous switch from to . furthermore, one can choose whether to update components simultaneously (synchronous update; kauffman, ) or to update one component at a time (asyn- chronous update, for which there are different approaches, see below; thomas and d’ari, ). in the synchronous case, the next state is entirely determined by the previous one, so that one can write, as before: sðt Þ ¼ fðsðt Þ; p ; p ; . ; pmÞ; t > t : ð Þ here, s(t) is a boolean vector, a list of s and s representing the state of each gene in the network. once the system is at an attractor, the system will cycle between different states, so that s →s f(s )→ . → sn f(sn )→s f(sn) in some repetitive fashion. steady states correspond to cycles of length , whereas for oscillations the cycle will consist of two states or more. in general, both the transient dynamics (i.e., how it changes over time before it settles to an attractor) and oscillations are systems approaches to regulatory networks different depending whether the updates are synchronous or asynchronous (and also which rule is chosen for the asynchro- nous case; see below). however, steady states are identical for both types of update. it follows that the simpler synchronous update schemes are often used if one wishes to study only the steady states of the system, whereas asynchronous is better suited to study the dynamics of the system. for an asynchro- nous update, the choice of which gene is updated at each time step can be made in several ways, which may be defined as follows: ( ) globally, for instance, by specifying an order in which genes are updated, ( ) based on a specific delay for each gene, which is compared with a global clock and reset after a change of state, or ( ) as a stochastic event: at each time step, one gene is chosen randomly and updated (li et al., ). in fact, more general random update functions can be used (shmulevich et al. ). cases and above require some numeric parameters to specify the model. more generally, boolean models may re- quire ( ) no quantitative parameters at all, all regulatory functions being specified using logical gates (e.g., and, not, or); ( ) time delay parameters for asynchronous updates (as in points and above); and ( ) weights for each input of regulatory function, together with a threshold (with which the weighted sum of inputs is compared; this approach being inspired by neural network models). figure . ingredients for a small network model. (a) modularity of hormone signaling in plants. the aux/iaa negative feedback model (middleton et al., ) was formulated using the law of mass action (see figures b and c); illustrative equations are provided. auxre, auxin response elements (arf binding sites). (b) top-down approach to small network generation. cluster analysis performed on the arf-aux/iaa interactome. from this the interactions between repressor and activator arfs and aux/iaa were identified (vernoux et al., ; compare with middleton et al., ). the plant cell example: the mutual inhibition feedback loop to illustrate the main ideas mentioned above, we now consider a well-known example, with two genes inhibiting each other; this sometimes is called a toggle switch or a mutual inhibition feedback loop (figure d; cherry and adler, ; gardner et al., ). models of this network can be formulated using either boolean or ode-based approaches. in the case of an ode model, the vari- ables are the expression level of the two genes (namely, gene and gene ). since there are only two variables, we visualize the dynamics of the system by plotting the expression level of gene against the expression level of gene (instead of their levels against time). example trajectories of the model are illustrated (figure d). we also plot nullclines; these indicate when the rate of change of just one gene is zero; steady states are at the inter- sections of the two nullclines (i.e., so that the rate of change for both genes is zero). we see from figure d that the system is bistable: there are two stable steady states (where one of the genes is expressed at a high level and the other is expressed at a low level) and an unstable one (where the two genes are ex- pressed at a comparable level). we also note that the (stable) steady state to which the system evolves depends crucially on the initial starting point (i.e., in which basin of attraction we start the system). in the boolean case (it being much simpler), we can write the model in terms of the regulatory rules, namely, gene (t+ ) = not[gene (t)] and gene (t+ ) = not[gene (t)]. however, we must choose an update method (see above). for a synchronous update, the behavior of the network is summarized in table , and a schematic representation is provided in figure d (where arrows indicate transitions between states). the stable steady states are analogous to the ones from the ode model, these being (in terms of a boolean vector) and (i.e., one gene is “on” and the other one gene is “off”). however, a key difference with the ode-based model is that if we started at or , the system would cycle between them; and can only be attained if we start the system at that state. thus, synchronous update is not required or helpful if one wishes to study how the network behaves over time but does give information on the steady states of the system. the case of asynchronous update is also illustrated in figure d. states and are again stable steady states of the system. however, we now find that if started at or , the system will tend to either or . hence, and are in the basins of attraction of and (figure d). however, the manner in which this network changes over time (i.e., its dynamics) will depend on which particular asynchronous update method is used. thus, unlike ode-based models, there is a degree of ambiguity asso- ciated with the transients of boolean networks. however, addi- tional parameters specifying the response time of both genes may help reduce this ambiguity and give more biological meaning to the transients of the model. parameters and parameterization of models we have seen that both boolean and ode-based models con- tain parameters. the behavior of both types of model can de- pend strongly on their parameter values. in many cases, estimates for these parameters are not yet available. for some problems, however, even qualitative predictions can give new biological insight. in this case, one can simulate the model for different parameter values (i.e., explore the parameter space and iden- tify each of the various behaviors that it can generate). the predictive capabilities of the model will thus depend on how much of the parameter space can be explored, and the dif- ferent behaviors can be treated as different predictions that subsequently can be tested experimentally. this includes sit- uations, for example, where one demonstrates the existence of sustained oscillations or bistability for biologically plausible parameters (françois and hakim, ; middleton et al., ; muraro et al., ). in some situations, however, it can be more important that a model generates quantitative predictions. this may be the case, for example, when one is interested in the sensitivity of the network outputs to some stimulus. in this case, parameter estimates can be obtained by fitting quantitative data to the relevant model outputs. for example, this was recently done with a model of gibberellin (ga) signaling network (middleton et al., ) and with the auxin signal transduction pathway (band et al., c) in conjunction with the novel auxin reporter, dii-venus (brunoud et al., ). these are both discussed further below. a detailed discussion of parameter estimation is beyond the scope of this review (reviewed in ashyraliyev et al., ). for our purposes, however, it is important to note that larger models typically have more parameters and that the more parameters to be estimated, the more difficult it becomes to generate an accurate model. even for small network models, however, it is often the case that estimates for model parameters are not in fact well constrained by the data. in other words, it is possible that from two equally good model fits one obtains two different parameter sets with significantly different estimates for the in- dividual parameters (this being referred to as sloppiness in the fitting problem; gutenkunst et al., ). however, even if this is the case, one can still use the different parameter sets to identify qualitatively distinct model behaviors. these in turn can be treated as predictions to be tested for experimentally (see below for a further discussion of model-experiment loop). thus, in sum- mary, it is not always necessary for good parameter estimates to be available for a model to be predictive or insightful. small-scale networks why using small scale networks makes sense small-scale networks are often generated via bottom-up ap- proaches of network discovery, where one starts with a gene, table . summary of transitions between different states for a boolean model of the mutual inhibition feedback loop (illustrated in figure d) for synchronous update (gene ,gene ) t (gene ,gene ) t+ systems approaches to regulatory networks protein, or signaling molecule of interest and works outwards, finding other components it interacts with. from these small networks, relatively simple models can be generated (see the next section for examples) for which it is often possible to identify all the possible behaviors of the network for plausible parameter values (see above). the usefulness of such a model (and indeed of any model) is apparent if there is a discrepancy between what is predicted by the model and what is observed experimentally, this suggesting that it might be necessary to include novel components in the model. in this way, dynamical models can help in predicting candidate components or in- teractions whose existence has then to be determined through experimentation. this is discussed further below. one limitation of the above strategy is that it relies heavily on our ability to explore all the possible behaviors of a particular model. as noted above, experience with even simple networks shows their behavior can often be highly counterintuitive and strongly depend on system parameters. for larger networks, such a comprehensive analysis of the dynamics can be even more difficult; increasing the number of model components and parameters can lead to an explosion in the combinatorial com- plexity of the problem. thus, for systems with more than a handful of variables, we rely mostly on computer simulation to understand their dynamics and hence can rarely be sure that we have fully explored all the possible system behaviors. this can significantly impair our ability to make robust or predictive models for larger-scale networks. thus, there are two main conceptual difficulties with large-scale networks: our inability to parameterize them and our inability, except in special cases, to fully classify their behavior. one way to overcome the above is in fact to rely on the analysis of small networks and furthermore to consider them as modules of a much larger and complex network. in this way, the dynamics of each module can be studied individually (see below for examples). in particular, there is an increasing body of evidence that biological systems are modular in their organization (hartwell et al., ; milo et al., ; spirin and mirny, ; stuart et al., ; gavin et al., ; alon, ; peregrín-alvarez et al., ). the isolation of modules can be based upon a bottom-up approach (described above) or by a top-down approach, identifying modules based on the connectivity in large-scale networks. one notable example of this is through the identification of network motifs, these being small networks (for which there are only a few nodes) with a sta- tistically significant topology. nevertheless, we would like to stress that the extent to which we can study the dynamics of large-scale networks by dividing them into smaller-scale ones (i.e., modules) remains to be fully understood. we discuss this further in the conclusion and future challenges section. how to build and analyze small networks as we have now discussed, small-scale networks are appealing because we can build models that are simple enough to analyze and retain enough mechanistic detail to be insightful for the biology. hence, whereas large network models typically involve phenomenological descriptions for the least known interactions, it is often possible to build small network models using only the laws of physics and chemistry. there is no definitive recipe to build a good model. however, one should keep in mind that dialogue between experimentalist and modeler is essential to the success of a modeling approach. while there has been much in the systems biology literature about the experiment- model cycle, it is often not emphasized that this cycle can ex- tend over long period of times and that there are many stages of modeling. models of small-scale networks are typically based on known interactions. for particularly well-characterized path- ways, a model is initially expected to capture the known ex- perimental observations (at least qualitatively). in the second stage of modeling, various perturbations of the model (e.g., hormonal, chemical, or genetic) should be simulated. at this stage, model outputs can be considered to be predictions that must be validated experimentally. often, it is only if new data sets have been generated (based on the model predictions) that new insight can be obtained. as mentioned in the previous section, the most useful scenario is when there is in fact a dis- crepancy between a prediction and the resulting experimental observation, as it can point to the existence of missing com- ponents, which subsequently can be identified through further numerical and wet-lab investigations. this type of multidisci- plinary exchange has, for instance, led to the discovery of novel feedback loops involved in the circadian clock of arabidopsis thaliana, an illustrative example that will be discussed further below (locke et al., a, b, ; zeilinger et al., ). while such exemplar studies exist, it is more often the case that model-based investigations will stop at the first stage, this being when existing experimental observations can be accounted for by the model and new model predictions have been generated but remain to be validated. this can lead to the perception that dynamical models have trouble predicting novel components or providing new insight. however, we argue that this is merely because subsequent rounds of the model-experiment loop have not yet been performed. the modeler-experimentalist dialogue is also crucial in de- ciding how much detail is available to include in the model and, hence, which framework (e.g., boolean or ode-based) should be used. this can reflect a number of important factors, including how well characterized the network is experimentally (i.e., the level of mechanistic detail available), the biological question to be answered, and whether quantitative time-resolved data on the various network components is available. since boolean networks explicitly assume that genes (and other network components) are either on or off, they typically require far less mechanistic detail to develop and, hence, often contain fewer parameters than their ode-based counterparts. thus, one can quickly characterize the overall behavior of the system. boolean networks are most likely relevant in situations where the system has multiple steady states. for example, this can be the case in developmental processes involving cell dif- ferentiation, where the different steady states correspond to the different cell fates (these being characterized by the expression of specific genes). we discuss this further below with examples in root epidermis and flower patterning (mendoza et al., ; espinosa-soto et al., ; savage et al., ). because of the intrinsic state representation used in boolean networks, it can sometimes be difficult to relate their outputs to the real dynamic behavior of the system. ode-based approaches the plant cell may therefore be more desirable, particularly if the system outputs of interest are intrinsically continuous. as an example of an ode-based model, figure a shows the network diagram and some of the corresponding equations for a model of auxin signal transduction (middleton et al., ). the equations for auxin and its binding to its f-box coreceptor transport inhibitor resistant (tir ) are shown in figure a. these are based on the law of mass action (figure d). the auxin signaling pathway is one of the best characterized in plants, extensive knowledge of which has been produced using bio- chemical, genetic, and genomic approaches (see overview in del bianco and kepinski, ). taking this information into account, the model includes various reactions between auxin and the proteins known to mediate transcriptional responses to auxin (a single auxin response factor [arf], an auxin/indole- -acetic acid [aux/iaa], and the coreceptor tir that controls degradation of the aux/iaa in response to auxin; chapman and estelle, ) and translation and decay rates of the mrnas. in the model, transcription of the aux/iaa is positively regulated by arfs (although in reality there are also repressor arfs), and this interaction is antagonized by aux/iaa proteins. this an- tagonism establishes a negative feedback loop in the network. the model equations are derived using the law of mass action together with an aux/iaa transcription rate that is a complex function of arf, arf dimers, and arf-aux/iaa. it should be noted that while it is not always possible to have such a precise mechanistic description of the system, one could instead use more phenomenological approaches by introducing quantitative concepts. examples of these include growth rates (kennaway et al., ), a function describing the size of a stem cell population (geier et al., ), or the gradient of an unknown diffusing signal (jönsson et al., ; kennaway et al., ). these help avoid having to include specific molecular details. because ode-based models can capture a high degree of biological detail, they can easily become large and overly com- plicated. thus, one key aspect of ode-based model de- velopment is that of simplification. one common approach is to retain the quantitative effects of certain molecular players or processes, without including them explicitly in the model so there are fewer variables or parameters. probably the best ex- ample of this is the quasi–steady state assumption. this as- sumes that some subset of reactions or processes occur on a much faster timescale than others (i.e., there is a separation of timescales), which allows the elimination of certain variables from the dynamic model (murray, ). for instance, the auxin sig- naling model by vernoux et al. ( ) reduces the binding of tir receptors with auxin and aux/iaa to a simple michaelis- menten term in the equations (figure a) by assuming this processes is fast when compared with changes in gene ex- pression. this type of reduction is also often used to eliminate the variables describing dimers from a system, assuming protein– protein binding is much faster than the processes such as tran- scription or translation (for example, see savage et al., ; van mourik et al., ; band et al., c). however, it is worth stressing that the quasi–steady state assumption can lead to the wrong dynamics if this assumption is not valid (i.e., if there is not a clear separation of timescales). its validity thus needs a careful evaluation, again requiring the experimentalist-modeler dialogue. the choice of network components to be modeled can also allow for simplifications. organisms such as arabidopsis typi- cally have large gene families in their genome (such as the aux/iaas and arfs; chapman and estelle, ), and it is common for modelers to try and reduce this complexity by lumping whole gene families together so that they are repre- sented by a single variable (for example, see middleton et al., ; van mourik et al., ). this is a reasonable first step and is most likely a valid one provided the individual family members all have similar behavior. however, it is often the case that individual gene family members have rather distinct functions (for example, see bridge et al., ) or that subsets of genes can be grouped together in a more systematic way (for example, using clustering-based approaches; vernoux et al., ). fur- thermore, it may be possible to isolate network components according to where (i.e., in which tissue) and when (i.e., during a developmental process) they are active. examples of this type of approach include the study of isolated modules from the auxin signaling pathway, like the pairs aux/iaa -arf , arf , or aux/iaa -arf , which have been shown to be active in a specific temporal sequence (de smet et al., ). using small-scale network modeling to unravel the biological logic underlying plant development cell-autonomous small-scale networks in systems biology, mathematical or computational models are often used to ascertain whether a particular set of proposed interactions (e.g., a gene network) can explain the biological observations. a way to start addressing this is simply to analyze a model’s behavior (using some of the techniques outlined above). in particular, the model itself may behave in an unin- tuitive or unexpected way, and through this process one can obtain a clearer interpretation of a specific data set and hence gain a better understanding of the real system. an excellent example of the use of small-scale models to enhance biological understanding can be found in the work of millar and coworkers on the plant circadian rhythm, already mentioned earlier (locke et al., a, b, ). a number of articles (for an overview, see dalchau, ) show how an iterative cycle of model refinement, validation, and comparison to new data has led to the discovery of new network compo- nents and a clearer understanding of how the interlocking feedback loops regulate the rhythm. the first four stages of model development are illustrated in figure . this process started with a single oscillator model (figure a) involving only late elongated hypocotyl/circadian clock asso- ciated (lhy/cca ) and timing of cab (toc ) (locke et al., a). comparisons between this model and (what was then) already published data showed that, while the model could correctly reproduce the phases of lhy and toc os- cillations, it failed to account for a number of experimental observations (locke et al., b). this indicated that addi- tional components might be missing from the model and led the authors to consider other possible interactions. the most systems approaches to regulatory networks promising of these involved an additional step in the feedback loop whereby toc activated lhy via a putative gene x (fig- ure b). this new model could account for the published ex- perimental observations. we note that this point in the authors’ studies reflects perhaps the first stage in the model-experiment loop discussed above. however, the authors went further to compare the model behavior and novel data generated from cca lhy double mutants. again, the model failed to account for the new experimental observations. the above process was therefore repeated again and a new component proposed (initially referred to as gene y), this forming a second loop in the network (figure c). the gene gigantea (gi) was initially proposed to be a candidate for gene y (locke et al., b, ). more recently, further interplay between model and experiment has indicated that gi only fulfills part of this function (pokhilko et al., ). further- more, the component originally proposed to be gene x could rather be the posttranscriptional modification of toc protein or its interaction with other complexes. collectively, these studies have led to a data-consistent view that circadian rhythms are driven by at least two oscillators (morning and evening). these are figure . unraveling the circadian clock. (a) the initial model for the circadian clock involved interaction between toc and lhy /cca . (b) to account for discrepancies between the model and data, an additional component in the network was proposed (gene x), which mediates lhy/ toc activation. (c) further comparison between new experimental data and the model indicated that the circadian clock involves two interlocking feedback loops, this comprising the original loop and feedback between putative gene y and toc . (d) while gi was proposed as a candidate for y, even further experimental validation revealed that this only fulfils part of the role. furthermore, gene x has subsequently been proposed to reflect toc modification or protein binding. the plant cell coupled intracellularly and involve nontranscriptional regulations (pokhilko et al., ) (figure d). another level of complexity was recently explored by guerriero et al. ( ). here, the authors investigated how stochasticity (caused by there being small numbers of molecules) can affect the behavior of the system. it was found that their stochastic model can provide a better agreement with experiments than the previous ode-based models. in particular, an observed dampening of oscillations in constant light could be explained by noise-induced desynchro- nization in a cell population, and a more realistic entrainment to light under changes of photoperiod was also achieved. small-scale network analysis has also been instrumental in advancing our knowledge on how plant cells process hormonal signals. in li et al. ( ), the authors considered the role of abscisic acid signaling in the control of stomatal closure. after collecting biochemical, genetic, and pharmacological data, the authors built an interaction network involving more than elements to model abscisic acid–dependent stomatal closure. in the absence of quantitative information on the pathway, such as the relative timings of the activity of these elements, they chose a boolean model with asynchronous update (see above) based on randomly chosen relative timings. simulations with , random initial states were performed, from which probabilities of stomatal closure at a given time were estimated. similar simu- lations were also performed in situations mimicking known mutations. from these, the authors predicted the most crucial elements of the network, in terms of the effect that the removal of an element (i.e., an in silico mutation) has on the typical time to reach steady state or on the sensitivity of the network’s re- sponse. these predictions were consistent with experimental observations on the mutants from the literature, thus confirming the predictive value of the model. several groups have also independently built models of auxin signaling and response. middleton et al. ( ) developed the first such model; above we described how it was built (figure a). the model can generate qualitative predictions about how this network might respond to changes in exogenous auxin and help explain why the transcriptional response of aux/iaa genes to auxin treatment can vary from family member to family member (abel et al., ). in particular, the data of abel et al. ( ) indicate that, depending on the family member, an aux/iaa gene will make one of three distinct types of response to treatment with exogenous auxin. first, over relatively short treatments (namely h), aux/iaa transcript levels can rise gradually and reach a steady state level. second, transcript levels rise to reach a peak and then decrease to an upregulated steady state level. in this case, we say the system overshoots the steady state. third, expression levels peak as before but now decrease back to their initial untreated levels. the model can account for the first two types of behavior, which reflect different parameter regimes of the model. however, the third type of aux/iaa tran- scription behavior in response to auxin could not be observed in the model. this indicates that (in this case) additional regulatory mechanisms must be at work. biologically, such parameter re- gimes could result from interactions of different aux/iaas and arfs, for which a significant diversity of biochemical properties (i.e., association and dissociation rates) are expected. notably, aux/iaa proteins can have quite distinct half-lives and binding affinities (dreher et al., ; calderón villalobos et al., ). it is important to note that these changes in aux/iaa mrna are observed in the model even though intracellular auxin levels are predicted to rapidly increase and reach equilibrium. in other words, just because the gene expression levels are changing in time, it does not mean that auxin levels are. furthermore, it was also found that the network could generate oscillations in aux/iaa mrna levels, even though free auxin levels are pre- dicted to be more or less constant. interestingly, oscillations of the dr auxin-inducible reporter have been observed in the root basal meristem and are thought to regulate the initiation of lateral roots (de smet et al., ). although it was proposed that the dr oscillations might be under the control of an auxin-in- dependent clock mechanism (moreno-risueno et al., ), these simulations also open the possibility that they might result in part from the aux/iaa feedback loop itself. vernoux et al. ( ) explored this pathway further by first obtaining a near-complete aux/iaa-arf interactome (there are aux/iaas and arfs). in particular, unlike middleton et al. ( ), the authors included repressor arfs in their model. using a graph clustering technique (illustrated in figure b), they show that the aux/iaa, activator arf, and repressor arf correspond to three classes having a specific structure of in- teraction profiles: aux/iaa interact with themselves and with activator arf; activator arf interacts with aux/iaa; and re- pressor arfs have very limited interactions. this analysis of the topology of the aux/iaa-arf network can be viewed as a top- down approach for generating a small network. the authors incorporated this information into their ode model. in particular, it should be noted that the repressor arf do not interact with the other proteins (as suggested by the interactome; figure b) but rather compete with the activator arf for the arf binding sites in the promoter of the auxin-inducible gene. in contrast with the model of middleton et al. ( ), the model by vernoux et al. ( ) can only reproduce the first type of behavior de- scribed above, an aux/iaa transcriptional response rising gradually to steady state with no overshoot. however, as already noted, a key difference between the models is that the latter implicitly assumes that the auxin perception pathway is quasi- steady, which could explain the discrepancy. the work of vernoux et al. ( ) is discussed further below. the ga signaling network is similar to that of auxin, in that bioactive gas act by targeting the degradation of a repressor protein (namely, members of the della family). della proteins mediate the transcriptional regulation of genes encoding ga biosynthesis enzymes (ga -oxidase and ga -oxidase) and the ga receptors (ga insensitive dwarf (gid ); among others). this naturally leads to a rather complex gene network, comprising several negative feedback loops. in middleton et al. ( ), the authors took the approach of parameterizing the model using both published and new data sets. in particular, they used quantitative time-course data on almost every as- pect of the network, including the signal transduction pathway (whereby ga binds to its receptor, gid ), the biosynthesis pathway (ga precursors are converted into the bioactive form via multiple enzyme-substrate reactions), and transcriptional responses to ga treatment. by doing so, they were able to constrain the model parameters according to the data. this systems approaches to regulatory networks can be thought of as a form of model calibration: it can ensure that the model can quantitatively reproduce the behavior of the system that has already been observed experimentally. how- ever, as noted before, the fitting process does not necessarily lead to a unique estimate for a parameter. in the case of the ga-signaling network, middleton et al. found that the param- eter sets obtained from each of their best fits generated similar qualitative predictions. in this way, the authors were able to explore how the different feedback loops modulated the sen- sitivity of a cell to changes in ga. small-scale networks underlying cell autonomous tissue patterning the models discussed above are all single-cell ones, in that spatial aspects are ignored. nevertheless, in certain circumstances, sin- gle cell models can also be used to bring insight to the spatial patterns observed. the first scenario is where the model has multiple stable steady states corresponding to different cell fates. this has been applied to the regulation of flower morphogenesis in arabidopsis (mendoza et al., , ; espinosa-soto et al., ; alvarez-buylla et al., ; sánchez-corrales et al., ). here, boolean network– based models were developed based on published data. in the models, good agreement was obtained between the steady states of the models and the experimentally observed gene expression patterns (this being the case for both wild-type and mutant plants). in doing so, they were led to hypothesize new regulations, which thus improved the knowledge of this system. since a boolean approach was used, a relatively high number of genes (around ) could be studied. however, more recently, an ode-based model (van mourik et al., ) of floral specification has been developed. the model reproduced known mutant behaviors for several mu- tations but also predicted new phenotypic effects of mutations yet to be tested. along similar ideas, la rota et al. ( ) collected data on the genes known to be important for floral development, including known interactions and experimentally observed expression patterns. these data were used to build a model for the speci- fication of sepal polarity, where cells differentiate into abaxial and adaxial tissue types. starting with genes, they were able to reduce the system to variables. using a boolean model, they were able to estimate the parameter values for which the steady states of their model were in good agreement with gene expression patterns in emerging sepals. this esti- mation led to the prediction of three novel pathways involving homeodomain leucine zipper ii, argonaute, and cytokinin- related genes, which can serve as a guide for future experimental investigations. another type of scenario where single-cell models can be used in the study of spatial patterning is where the expression patterns of particular network components are hard-coded into the model (rather than being emergent properties of it). this can be achieved by choosing model parameters to depend on space. an example of this can be found in vernoux et al. ( ), already discussed above. here, the authors used in situ hy- bridization to show a differential expression pattern of the arf genes between the center and the periphery of the shoot apical meristem (sam). parameters representing arf production were chosen to capture this observation in the model, namely, by considering low and high production of arfs as representative of the sam center and periphery, respectively. mathematical analysis and numerical simulations indicated that differential expression of activator and repressor arfs cause variations in the sensitivity of a cell’s transcriptional responses to auxin. in particular, it was found that there is low sensitivity to auxin in the center, while a high sensitivity is expected at the periphery. their results further suggested that in these two domains, the coex- pression of activator and repressor arfs provide cells with the ability to buffer gene expression against fluctuations in auxin. this view was confirmed after comparing the spatio-temporal patterns of the dii-venus auxin sensor (brunoud et al., ) in the sam with that of the dr auxin-inducible reporter (which gives information on the transcriptional response to auxin; sabatini et al., ). this indicated that the arf prepattern might explain (at least in part) why auxin can only induce organ formation at the periphery of the sam. another example of using small scale networks to understand cell-autonomous patterning is provided by band et al. ( b), wherein the ga signaling network model of middleton et al. ( ) was embedded in a multicellular model of the root. this allowed the authors to explore how the various components are affected as the cells in the root elongate and hormone concentration levels dilute; this is discussed further by band et al. ( a). small-scale networks to understand intercellular signaling and signal distribution in tissues in the previous section, we discussed how gene network models can be used to explore tissue patterning problems, even if the spatial aspect of the problem is not explicitly included in the model. this type of approach is particularly relevant when in- tercellular communication does not greatly affect the behavior of the networks (so that, in effect, cells respond autonomously). however, intercellular communication can be essential in plant patterning and can sometimes strongly influence the behavior of a given network. we discuss examples of this below. in savage et al. ( ), the authors used a boolean frame- work to explore the regulatory mechanisms underlying tricho- blast and atrichoblast patterning in arabidopsis root epidermis. to do this, they developed two competing network models in which caprice (cpc), werewolf (wer), and glabra (gl ) interact to regulate the patterning process. the first proposed mechanism involves a self-activation feedback loop for activation of wer, whereas the second corresponds to a mutual support mechanism where cpc inhibits wer and only intercellular movement of cpc can relieve this inhibition. since intercellular communication was a crucial aspect of the biology, both network models were embedded in a multicellu- lar geometry. these two networks and how their behaviors are impacted by the inclusion of intercellular communication are illustrated in figure . from their simulations, the authors were able to design an experiment that could distinguish between the two mechanisms. based on this, they were able to rule out the existence of wer self-activation in favor of the mutual support mechanism. the plant cell another example can be found in the study of the maintenance of the stem cell niche in the sam. a negative feedback loop between the wuschel (wus) transcription factor and the clavata (clv ) peptide regulates the size of the stem cell niche. several groups have described the dynamics of this sys- tem by means of ode-based models, both in wild-type and mutant plants. in the first such model, jönsson et al. ( ) showed that a simple ode-based model was able to robustly reproduce the sharp wus expression domain. here, the authors included a purely hypothetical repressing signal diffusing from the l layer, and a reaction-diffusion mechanism could activate the wus gene. models of this process have since increased in sophistication as new biological data have become available. in particular, the interplay between experimental approaches and modeling has provided strong support for the idea that cytokinin signaling is crucial for the positioning and regulation of the size of the wus and clv domains in the sam (gordon et al., ; hohm et al., ; yadav et al., ; chickarmane et al., ). here, cytokinin signaling is involved in the activation of wus expression (gordon et al., ). furthermore, movement of wus and repression of cytokinin biosynthesis by wus could establish a cytokinin gradient that in turn determines the position of wus domain (yadav et al., ). the repressing signal dif- fusing from the l predicted by jönsson et al. ( ) would thus rather be a gradient of an activator resulting from wus movement. auxin also functions as a key intercellular signal and is actively transported between cells. modeling has been used mainly to explore possible mechanisms explaining the dynamic properties of polar auxin transport in tissues. this has been covered in several reviews already (garnett et al., ; santos et al., ), and we will not discuss it here in detail. one of the major limi- tations in testing the predictions of the auxin transport models has been the absence of reliable tools to follow the spatio- temporal dynamics of auxin distribution in tissues. recently, band et al. ( c) were able combine the use of a novel auxin sensor, dii-venus, with a mathematical model to quantify auxin levels in tissues. dii-venus is composed of the auxin binding domain of the aux/iaa protein fused to a fast-maturing variant of yellow fluorescent protein, venus. to quantify this, the au- thors simplified the model by middleton et al. ( ), taking into account the fact that the protein is expressed under a constitu- tively active promoter and not acting as a repressor of gene transcription. excellent agreement between the model and high-resolution, time-resolved, auxin dose–response data were obtained. using the model, the authors were able to infer relative levels of endogenous auxin from the level of dii florescence. the authors next applied this model to study the role of auxin in gravitropism. here, auxin is thought to be redistributed to the lower half of the root. by taking this into account, the authors were able to infer from the dynamics that roots use a tipping point mechanism that operates to reverse the asymmetric auxin flow at figure . intercellular signaling and its impact on network dynamics. two competing models for root epidermal patterning considered in savage et al. ( ): (a) the wer self-activation model and (b) the mutual support mechanism. interactions and components that are not active in a cell appear faded. key differences between the two models appear in red. systems approaches to regulatory networks the midpoint of root bending (band et al., a). it is likely that this combination of modeling and experimental approaches can be extended to study auxin transport in other organs and will provide further key insight into the mechanisms regulating auxin distribution during developmental processes. conclusions and future challenges we discussed why, in many cases, it is productive to focus on small networks and outlined a number of examples where this approach has given significant biological insight (where small is beautiful). however, these successes inevitably lead to a drive to include further complexity in the modeling framework, the number of system components, both in terms of genes, pro- teins, and their interactions, but also in different cell types and spatial contexts. moving beyond deterministic models, such as those we have discussed, will be one of the challenges faced by the systems biology field. it can be done notably using stochastic models taking into account the inherent noise occurring in biological systems. increasing evidence suggests that transcriptional noise can have a major impact on gene network behavior, in particular at the single-cell level (raj and van oudenaarden, ; eldar and elowitz, ). as stochastic models are of a quantitative essence, their development requires advanced knowledge of systems under consideration and their study incurs a significant computational overhead. a notable recent example showed that stochasticity is a plausible explanation for several experimental observations on circadian oscillations at the cell population level (guerriero et al., ). as the understanding of other regulatory systems in plants increases, the constant evolution in compu- tational capacities should allow more in-depth exploration of how much additional knowledge can be gained from stochastic models. in parallel, a long-term trend to ever larger networks is evident and is raising the question of the number of network compo- nents that need to be considered. the answer to this is context dependent, but it is important to recall that simply increasing the number of components in a network does not automatically produce models that yield more information on the system dy- namics. as discussed earlier, in some cases, sets of genes and gene families can be subdivided into subsets with similar func- tionality to derive simplified models that still capture the system dynamics with sufficient accuracy. constructing models for larger networks will likely rely on coupling several small gene network models corresponding to specific modules, such as the auxin, cytokinin, and ga signaling pathways. this modularity offers the possibility to parameterize submodels in isolation (which reduces the complexity of param- eter estimation), before combining models together. a challenge for the community is to effectively share parameterized models in a way that allows them to be connected together. considerable progress in this regard is being made for nonspatial models via tools such as sbml (hucka et al., ), cellml (cuellar et al., ), and the biomodels database (li et al., ), but there is an ongoing challenge to do this in a spatial context. another major challenge for the systems biology community is indeed to develop efficient multiscale modeling approaches that allow integrating these models. this should help us understand the emergent properties of the biological system at the different scales. this requires building models that allow realistic simulations of growth and development. the foundations of such approaches are being established in plants, thanks to recent image analysis techniques that allow building realistic computer representa- tions of three-dimensional plant tissues (fernandez et al., ). for further details, we refer the reader to the review by band et al. ( a) in this issue. however, it is important to stress that at present the extent to which large-scale networks can be studied by dividing them into modules and reassembling them remains to be fully understood, in plants or, in fact, any organism. even in traditional biology, understanding a system by studying its parts independently is a hypothesis upon which many studies are based. gene regu- latory networks for the processes we have discussed have all been studied in a modular fashion. in reality there will be a de- gree of crosstalk between them. for example, the circadian clock and auxin signaling are traditionally studied independently, even though there is known to be interplay between the two (covington and harmer, ). very few examples of small- scale plant networks have been studied beyond the initial stages of modeling, and subjected to experimental validation, with the most notable exception of the circadian network we have dis- cussed. despite the obvious success obtained using small- network modeling, a full evaluation of this approach for gene network analysis will not be possible until a number of such small modules have been studied in depth and coupled to test their predictive value. testing model prediction requires the continuous production of relevant quantitative biological data. this is a major challenge for biologists, but constant innovations (ehrhardt and frommer, ) are opening fantastic opportunities for plant scientists. in particular, these will likely make it possible (in the near future) to follow in vivo a variety of variables at different scales, from the subcellular scale to entire plants. for gene regulatory networks, progress in live imaging techniques should make it feasible to follow dynamically a significant number of the variables in small networks. models will be essential in highlighting which are the most important variables to focus on, at least in the first steps of an analysis. the spatial organization of plants presents additional chal- lenges in the use of small-scale networks. as we have seen, cells in different locations may have different functional net- works (due to expression of different network components). to date, much of the work on model parameterization has relied on data from whole plants, or at least whole tissues, but the an- ticipated progress in experimental innovations means that in the future we should consider that parameters or the networks themselves differ in different cells. even for small-scale networks, it is likely that not all the inter- actions will be known. in this case, one approach is to generate a selection of mechanisms that account for existing experi- mental observations. mathematical models can then be used to generate predictions based on the different mechanisms and therefore suggest further experiments that help to distinguish between them. the simplest case is where an experiment can be designed so that two competing mechanisms generate the plant cell qualitatively distinct outputs (this being the case in savage et al. [ ], as discussed above). however, competing mechanisms may only generate quantitatively (but not qualitatively) different outputs. in this case, more sophisticated techniques are re- quired to distinguish between the models based on the data. at present, statistical tools exist or are in development to address this (see toni and stumpf, ; toni et al., ). in turn, however, these will challenge the experimental community to produce additional data that help justify model extensions on rigorous grounds. such statistical approaches should also allow prior knowledge (not necessarily quantitative) to be built in. finally, we draw attention to what was, and still is, a major challenge for the future of systems biology (that we hope this review helps to address), namely, that of training plant scientists with the skills to engage with mathematical model development and analysis. the scope of small-scale networks is ideal in this context; the models presented here, and others of similar complexity, represent exemplars of modeling and model anal- ysis that are possible to study without the use of heavy math- ematics or intensive computation. furthermore, they illustrate the kinds of phenomena (like steady states, stability, and bifur- cations) that should become familiar to the plant science com- munity, so that when, inevitably, larger scale models are used, we do not simply simulate them in a blind fashion. in addition, the plant science community has been particularly active in promoting training in mathematical modeling for life scientists, and funding bodies are increasingly demanding that postgraduate training in life sciences include some element of mathematical modeling and systems approaches. ultimately, it is hoped that systems approaches become strongly embedded in our funda- mental approach to practicing plant science. acknowledgments we apologize to colleagues if their work could not be included in this review due to space limitations. a.m.m. acknowledges support from the center for modeling and simulation in the biosciences of the university of heidelberg. m.r.o. acknowledges support from the centre for plant integrative biology, university of nottingham, which is jointly funded by the biotechnology and biological sciences research council/engineering and physical scien- ces research council grant bb/d as part of their systems biology initiative. t.v. and e.f. acknowledge support from the agence nationale de la recherche, partner of the erasysbio+ initiative supported under the european research area network plus scheme in fp (isam project). author contributions all authors contributed equally to writing this article. received june , ; revised september , ; accepted october , ; published october , . references abel, s., nguyen, m.d., and theologis, a. 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( ). wuschel protein movement mediates stem cell homeostasis in the arabidopsis shoot apex. genes dev. : – . zeilinger, m.n., farré, e.m., taylor, s.r., kay, s.a., and doyle, f.j. iii ( ). a novel computational model of the circadian clock in arabi- dopsis that incorporates prr and prr . mol. syst. biol. : . systems approaches to regulatory networks doi . /tpc. . ; originally published online october , ; ; ; - plant cell alistair m. middleton, etienne farcot, markus r. owen and teva vernoux modeling regulatory networks to understand plant development: small is beautiful this information is current as of april , references /content/ / / .full.html#ref-list- this article cites articles, of which can be accessed free at: permissions https://www.copyright.com/ccc/openurl.do?sid=pd_hw x&issn= x&wt.mc_id=pd_hw x etocs http://www.plantcell.org/cgi/alerts/ctmain sign up for etocs at: citetrack alerts http://www.plantcell.org/cgi/alerts/ctmain sign up for citetrack alerts at: subscription information http://www.aspb.org/publications/subscriptions.cfm is available at:plant physiology and the plant cellsubscription information for advancing the science of plant biology © american society of plant biologists https://www.copyright.com/ccc/openurl.do?sid=pd_hw x&issn= x&wt.mc_id=pd_hw x http://www.plantcell.org/cgi/alerts/ctmain http://www.plantcell.org/cgi/alerts/ctmain http://www.aspb.org/publications/subscriptions.cfm version_april_ .pdf when warm glow burns: motivational (mis)allocation in the non-pro�t sector� gani aldashevy esteban jaimovichz thierry verdierx april , abstract we build an occupational-choice general-equilibrium model of an economy with the non-pro�t sector �nanced through private warm-glow donations. lack of monitoring on the use of funds implies that an increase of funds of the non-pro�t sector (because of a higher income in the for-pro�t sector, a stronger preference for giving, or an in�ow of foreign aid) worsens the motivational composition and performance of the non-pro�t sector. if motivated donors give more than unmotivated ones, there exist two stable (motivational) equilibria. linking donations to the motivational composition of the non-pro�t sector or a tax-�nanced public funding of non-pro�ts can eliminate the bad equilibrium. keywords: non-pro�torganizations, charitablegiving, altruism, occupational choice, foreign aid. jel codes: l , d , j , d . �we thank emmanuelle auriol, roland benabou, maitreesh ghatak, andy newman, cecilia navarra, susana peralta, jean-philippe platteau, paul seabright, pedro vicente, and the participants at the n.g.o. (non-pro�ts, governments, organizations) workshop (london), ose workshop (paris), and seminar partic- ipants at collegio carlo alberto, nova university of lisbon, tinbergen institute and university of sussex for useful suggestions. ydepartment of economics and cred, university of namur, and ecares (ulb). mailing address: de- partment of economics, rempart de la vierge, namur, belgium. email: gani.aldashev@fundp.ac.be. zuniversity of surrey. mailing address: school of economics, guildford, surrey, gu xh, uk. email: e.jaimovich@surrey.ac.uk. xcorresponding author: paris school of economics and cepr. mailing address: pse, boulevard jourdan, paris, france. email: verdier@pse.ens.fr. introduction one of the major recent phenomena in both developing and developed countries is the rising importance of the provision of public goods through private non-pro�t organizations. in the developing world, the non-governmental organizations (ngos) play a key role in provision of health and education services and are fundamental actors of empowerment of socially disadvantages groups (such as women and minorities) and of monitoring the adherence by �rms to environmental and labor standards. the number of international ngos wordwide increased from less than in mid- s to more than in (union of international associations ; see also werker and ahmed ). similarly, in the oecd countries, the role of non-pro�t organizations in providing public goods is considerable, especially in health, arts, education, and poverty relief (see bilodeau and steinberg , section . , for a detailed analysis of the scope of the non-pro�t sector). this sector has a large weight in terms of employment: on average, . % of the economically active population is employed in the non-pro�t sector, and for some countries (belgium, netherlands, canada, u.k., ireland) this share exceeds % (salamon ). one distinctive feature concerning the provision of public goods by non-pro�ts and ngos is their �nancing structure: while a part of these organizations� operational cost is covered by government grants and by user fees, voluntary private donations play a key role in the �nancing of their budgets. bilodeau and steinberg ( : ) report that, on average, for the countries for which comparable data on non-pro�ts is available, over % of their �nancing comes from voluntary private giving. more than three-quarters of this amount actually consists of small donations. given the public-good nature of the services typically provided by non-pro�ts, and the fact that small donors could hardly expect their contribu- tions to have any meaningful e¤ect on total provision, this evidence suggests that private contributions to non-pro�ts must be partially motivated by some strong form of impure altruism. recent research inpublicandexperimental economicshas indeedshownthat rationalizing empirical regularities about giving requires the acknowledgment of private psychological bene�ts accruing to the donor from the act of giving. this is the so-called "warm-glow" motivation, �rst modelled by andreoni ( ). using a panel of donations and government funding from the u.s. to international relief and development organizations, ribar and wilhelm ( ) �nd that only the warm-glow motive is consistent with the observed absence of crowding out of private donations to non-pro�ts. in laboratory experiments, andreoni and miller ( ) and korenok et al. ( ) �nd that voluntary giving tends to respond to income variations in a way that is more in line with the warm-glow motive than with pure altruism. a �eld experiment by tonin and vlassopoulos ( ) reaches analogous results. the authors analyze the behavior of student workers who had to exert real e¤ort on a data entry task, and �nd that in an environment that elicits warm glow altruism workers respond by increasing e¤ort, while additionally eliciting pure altruism has no further e¤ect on e¤ort. non-pro�t organizations rely then heavily on private donors� contributions, which are to a large extent the result of some intrinsic "joy of giving". the prevalence of impure altruism by donors means that the link between the motivation to give to non-pro�t organizations and the ultimate provision of public-goods by them is weak. in addition, the very nature of the goods and services provided by these organizations is such that it is virtually impossible to write contracts that condition payment or future donations on the output produced by these entities (see hansmann, , chapter ; and bilodeau and slivinski, a, section . , for detailed discussions). these features, combined with the fact that individual producers� intrinsic motivation is private information, imply that the non-pro�t sector is subject to large scope for funds diversion and rent-seeking by the founders/managers of non-pro�ts. there is someevidenceofopportunisticbehavior in thenon-pro�t sector. onetypicalway through which the society tries to limit the scope for funds diversion is the non-distribution constraint, which entails that the organization cannot distribute pro�ts but must reinvest them towards the ful�llment of its mission (hansmann, : - ). however, a clear downside of this policy is that it lowers the incentives to cut costs. moreover, given the di¢culty to control how these costs are calculated, it often spurs in-kind diversion. for instance, smillie ( : - ) describes how development-oriented non-pro�ts use in�ated and hidden overheads to engage in the in-kind diversion of funds. frumkin and keating ( ) analyze the non-pro�t executive pay patterns and conclude that "ceo compensation is signi�cantly higher in non-pro�t organizations where free cash �ow is present". malani in a recent paper, using an instrumental-variable approach, andreoni and payne ( ) document sub- stantial crowding out of private giving to charities by government grants (about %). virtually all of the crowding out is caused by non-pro�ts strategically reducing fundraising (rather than donors responding to grants by consciously decreasing their donations). in this paper, we mostly focus of the joy-of-giving (or warm-glow) motive for giving. however, an additional reason why people might be willing to donate is social-signalling, as modelled by benabou and tirole ( ). social-signalling motivation would complement and reinforce the joy-of-giving motive that we focus on in our model. and choi ( ) exploit the executive compensation data from nursing homes in the u.s. and �nd that non-pro�t managers behave as if they cared about pro�ts as much as their counterparts in for-pro�t �rms. finally, fisman and hubbard ( ) �nd that non-pro�ts in the u.s. states with weaker oversight have managerial compensation that is more highly correlated with donation �ows and allocate a smaller percentage of donations to the �rm�s endowment. one important implication of these facts is that the �nancing of the non-pro�t sector might have an impact on the composition of the sector, particularly in terms of the level of intrinsic motivation of its managers. economists have so far analyzed separately the issues of non-contractability and poor monitoring in the non-pro�t sector, sorting into mission-oriented organizations, and the op- timal �nancing of non-pro�t organizations. however, we still lack a model that ties all these key elements together within a tractable general equilibrium framework. complementing the previous literature with a general equilibrium analysis is crucial, given that the relative size of the non-pro�t sector in numerous countries (both developing and developed) is large enough to imply that policies that in�uence the behavior of non-pro�t managers and entry into the sector might importantly a¤ect the returns in both the non-pro�t and for-pro�t sec- tors. as a consequence, partial equilibrium approaches may lead to wrong policy conclusions (for instance, concerning the desirability of more extensive state �nancing to non-pro�ts or channeling foreign aid via ngos). this paper proposes a tractable occupational-choice model with for-pro�t �rms, non- pro�t organizations and endogenous private donations. the model relies on four key as- sumptions. first, private donors give to non-pro�ts essentially because of warm-glow motives (i.e., with a weak link to the expected public-good output generated by the particular do- nation). second, individuals self-select either into the for-pro�t or non-pro�t sectors. third, monitoring the behavior and knowing the intrinsic motivation of the non-pro�t managers is inherently di¢cult. fourth (and also resulting from the non-measurability of non-pro�ts� output), private donations to the non-pro�t sector are shared among the existing non-pro�ts �rms in a manner that is not strictly related to their performance. the model aims at addressing the following set of questions. what is the equilibrium there is substantial narrative evidence several developing countries that generous �nancing by foreign aid, together with a strong new emphasis on decentralized development, has led to perverse e¤ects by triggering opportunistic behavior and elite capture in these local ngo projects (see, e.g., platteau and gaspart, ; platteau, ; the contributions in bierschenk et al., ; gueneau and leconte, , for chad; and bano, , for pakistan). composition of the non-pro�t and for-pro�t sectors in terms agents� intrinsic motivation? what are the implications of the external �nancing on the behavior of the non-pro�t sec- tor? what types of policies can improve the motivational composition of the non-pro�t sector? what happens when donations respond positively to a better perceived motivational composition of the non-pro�t sector? the main mechanism in our model rests on the notion that self-selection into either the for-pro�t or non-pro�t sectors is altered by the level of donations received by non-pro�t �rms in equilibrium. imperfect monitoring of managers in the non-pro�t sector, together with warm-glow motives by private donors, implies that the scope for rent-seeking in this sector expands when private giving grows. we show that warm-glow altruism and self- selection, in a context of asymmetric information about non-pro�ts managers� motivation, interact sometimes in non-monotonic ways, leading in certain cases to ine¢cient equilibrium outcomes and allocations. our model generates the following �ve main results. first, there exist cases in which rent-seeking motives crowd out altruistic motivation from the non-pro�t sector. when this occurs, the non-pro�t sector ends up being managed by intrinsically self-interested agents who exploit the lack of monitoring to divert funds for their private use. moreover, since the scope for rent-extraction rises with the level of donations received by each non-pro�t �rm, this misallocation problem is exacerbated in richer economies and in economies where private donors give more generously. second, foreign aid intermediation through the non-pro�t/ngo sector in a developing country may entail perverse e¤ects: it may cause the economy to switch from an equilibrium with a good allocation to one with a bad allocation of pro-social motivation. one implication of this result is that, in our model, total output of the non-pro�t sector becomes a non- monotonic function of the amount of foreign aid. at low levels of foreign aid, a small increase in aid leads to higher total ngo output, since the allocation of motivation in the non-pro�t sector remains intact, and the motivated managers can produce more with more funds. however, with larger increases in foreign aid, as soon as the motivational composition of the sector starts to change (because of the crowding out e¤ect), total non-pro�t output declines. such inverted u-shaped relation, in turn, can help explaining the micro-macro paradox observed by empirical studies of aid e¤ectiveness (i.e. the absence of empirical positive e¤ect of aid on output at the aggregate level, combined with numerous positive �ndings at the micro level). third, if pro-socially motivated donors exhibit a higher propensity to give out of their private income than unmotivated ones, the model exhibits multiple equilibria. in particular, for intermediate ranges of private income, the model sustains two very di¤erent types of equilibria. in one equilibrium there is a high level of pro-social motivation in the non-pro�t sector, while in the other one the non-pro�t sector is fully managed by unmotivated agents. the underlying reason for equilibria multiplicity is that when the private sector is rich in altruistic motivation, a large amount of aggregate donations are given to the non-pro�t sector, thereby expanding the scope for rent-extraction by non-pro�t managers. conversely, when the private sector rich in self-interested agents, only altruistic motivated agents end up being attracted to the non-pro�t sector in dearth of private donations. fourth, if donors� warm-glow motivation somehow responds positively to the expected productivity of the non-pro�t sector, the low-motivation equilibrium disappears. however, our model shows that, even in these cases, when the amount of donations becomes su¢ciently large, unmotivated agents will still end up constituting an important share of the pool of non-pro�t managers, hurting thus the aggregate provision of public goods. finally, we show that a properly designed public �nancing policy of the non-pro�t sec- tor may improve the motivational composition of the non-pro�t sector and eliminate the low-motivation equilibrium. this occurs because taxation alters the occupational choice of individuals in two ways: it reduces the returns in the private sector and increases the aggre- gate transfers to the non-pro�t sector. in a partial equilibrium setup, both channels would make the non-pro�t sector relatively more attractive for both motivated and unmotivated agents. however, in our framework, the implicit general equilibrium re-allocations imply that if public �nancing is able to increase the aggregate funding of the non-pro�t sector, while at the same time it su¢ciently increases the number of non-pro�t managers so that the funding that each non-pro�t �rm obtains from the aggregate pool is lower, this policy will lead to entry of motivated and exit of unmotivated agents from the non-pro�t sector. besides the aforementioned papers by andreoni ( ) and benabou and tirole ( ), our paper relates to several other key papers that study pro-social motivation and non-pro�t organizations: lakdawalla and philipson ( ), glaeser and shleifer ( ), françois ( , ), besley and ghatak ( ), and aldashev and verdier ( ). we contribute to this line of research by endogenizing the occupational choice decision of individuals and exploring the general equilibrium implications of the �nancing of the non-pro�t sector. the second related strand of literature is the occupational choice models applied to the selection into the public sector and politics (e.g., caselli and morelli, ; macchiavello, ; delfgaauw and dur, ; bond and glode, ; jaimovich and rud, ). we extend this line of ongoing research by analyzing how the selection mechanisms apply to the non-pro�t/ngo sector within a context of endogenous voluntary donations. finally, there is growing theoretical literature that studies the e¤ects of the modes and level of foreign aid �nancing on its e¤ectiveness (see, for example, the survey in bourguignon and platteau, a). among these studies, an early paper by svensson ( ) underlines howshort-termincreases inaid�ows maytrigger rent-seeking "wars" amongcompeting elites in a developing country. another interesting contribution is a recent paper by bourguignon and platteau ( b), which concentrates on moral hazard issues related to the increasing amounts of foreign aid (in particular, the e¤ect of domestic monitoring on the ultimate use of aid �ows). our model studies a separate and novel channel, previously unaddressed by the foreignaid literature: thatofmotivationaladverse selection into the sector that intermediates foreign aid �ows between outside donors and bene�ciaries. the rest of the paper is organized as follows. section builds our baseline model of occupational choice in the for-pro�tandnon-pro�t sectors; it also introducesandanalyzes the e¤ects of foreign aid and public �nancing on the e¢ciency of the non-pro�t sector. section provides an alternative setup with endogenous fundraising e¤ort by non-pro�t organizations, and shows that our main results remain essentially intact. section presents two further key extensions of the baseline model: allowing the donations by private entrepreneurs to be related to their degree of altruism, and letting donations depend positively on the expected output of the non-pro�t sector. section discusses the main premises and modelling choices, as well as the generalizability of our results to relaxing these assumptions. section discusses the main applications of our model, explores several avenues for future work, and concludes. basic model we consider an economy populated by a continuum of individuals with unit mass. there exist two occupational choices available to each agent: she may become either a private entrepreneur in the for-pro�t sector or a social entrepreneur by founding a �rm in the non- pro�t sector. henceforth, we will refer to the two types of �rms as private and non-pro�t �rms, respectively. for simplicity, we assume that each entrepreneur founds and manages only one �rm. let n denote the total mass of non-pro�t managers. all agents are identically skilled. however, they di¤er in their level of pro-social motiva- tion, denoted by mi. there exist two levels of mi, which we refer to henceforth as types: mh ("motivated") and ml ("unmotivated"), where mh > ml. the type mi is private informa- tion. for simplicity, we will focus only on the extreme case in which mh = and ml = . in addition, we assume the population is equally split between mh- and ml-types. . for-pro�t sector each private entrepreneur produces an identical amount of output. there are decreasing returns in the private sector, thus while the aggregate output is increasing in the mass of private entrepreneurs, �n, the output produced by each private entrepreneur is decreasing in �n. more precisely, we assume that each private entrepreneur produces y = a ( �n) �� , where < � < and a > : ( ) aggregate output is thus given by y = a( �n)�. this assumption of decreasing average output can be justi�ed if, for instance, each �rm is built around some marketable product idea, and the most productive ideas are discovered �rst; so as the number of private �rms increases, each additional �rm is built around an ever less productive idea. private-sector entrepreneurs derive utility from their consumption of the private good (c). in addition, they also enjoy warm-glow utility from donating to the non-pro�t sector (d). in particular, we assume all entrepreneurs have the same cobb-douglas type utility function: vp(c;d) = c ��d� � ( � �) �� , where < � < : ( ) private-sector entrepreneurs maximize ( ) subject to ( ). the solution of the maximiza- tion problem yields c� = ( � �)y and d� = �y, which in turn implies that, at the optimum, their indirect utility function is v �p = y: ( ) from the optimization problem of private-sector entrepreneurs, it follows that the total amount of entrepreneurial donations to the non-pro�t sector is d = � ( �n)� a: ( ) in section . we relax the assumption that warm-glow donations by private entrepreneurs are indepen- dent of their level of pro-social motivation by letting � be type-speci�c (�i), with �l = and < �h � . as can be readily observed from ( ) the total amount of donations increases with the pro- ductivity of the private sector (a), the number of private �rms ( �n), and the parameter determining the marginal utility of warm-glow giving (�). . non-pro�t sector the non-pro�t sector is composed by a continuum of non-pro�t �rms with total mass n. each non-pro�t �rm is run by a social entrepreneur. we think of each single non-pro�t �rm as a mission-oriented organization (as, for instance, in the seminal paper by besley and ghatak, ) with a narrow mission targeting one particular social problem (e.g., child malnutrition, air pollution, �ghting malaria, saving whales, etc.). each non-pro�t manager i collects an amount of donations �i from the aggregate pool of donations d. part of the collected donations �i is used to pay the wage of the non-pro�t manager wi, while the rest (the undistributed donations) is used as input for the production of the service towards the organization�s mission. we measure the e¤ectiveness (output) of each speci�c non-pro�t �rm by gi, which is a function of the undistributed donations (�i � wi). we assume that the output generated by each speci�c non-pro�t �rm exhibits decreasing returns with respect to the funds invested into the project, namely: gi = (�i �wi) , where < < : ( ) a non-pro�t manager derives utility from her own consumption (which equals her wage) and from her contribution to the solution of the social problem targeted by her organization�s mission (which is equal to gi). the weight placed oneachof two components of utility is given by the non-pro�t manager�s level of pro-social motivation mi. more precisely, we assume that the utility function of a non-pro�t manager with motivation mi is: ui(wi;gi) = w �mi i g mi i mmii ( �mi) �mi , where mi fmh;mlg: ( ) in line with the evidence discussed in the introduction, we assume that the non-pro�t sector su¤ers from poor monitoring by donors. for simplicity, we take the extreme assump- tion that non-pro�t managers enjoy full discretion in setting their own wage (subject to the feasibility constraint wi � �i). in addition, we assume that the pool of total donations d is equally shared by all non-pro�t �rms. then, donations collected by each non-pro�t �rm in section we relax this equal-sharing assumption by explicitly modelling fundraising e¤ort by non- pro�t managers. are: �i = d n = �a( �n)� n : notice that �i is decreasing in n through two distinct channels: �rstly, because total do- nations d decrease when the mass of private entrepreneurs ( � n) is smaller; secondly, because a rise in the mass of non-pro�t �rms n means that a given total pool of donations d must be split among a larger mass of non-pro�t �rms. given that mh = , motivated non-pro�t managers place all the weight in their utility function on g, and set accordingly w�h = . as a result, choosing to become a non-pro�t manager gives to a motivated agent the indirect utility equal to u�h = � d n � = � �a ( �n)� n � : ( ) analogously, given that ml = , unmotivated non-pro�t managers disregard contributing to their organizations� mission, and convert all the donations into their wages, w�l = �i. this implies that choosing to become a non-pro�t manager gives to an unmotivated agent the level of utility u�l = d n = �a ( �n)� n : ( ) we can now state the following: lemma let bn denote the level of n at which d( bn) = bn. then, u�h r u � l if and only if n r bn; where: (i) �a=( + �a) < bn < , (ii) bn is strictly increasing in a and � and strictly decreasing in �, (iii) lim a! bn = , (iv) lim �! bn = �a and lim �! bn = �a=( + �a). proof. u�h r u � l i¤ n r bn follows immediately from the expressions in ( ) and ( ). the rest of the results follow from noting that �a( � bn)�= bn = , and di¤erentiating this expression. lemma is a single-crossing result useful for our analysis. it states that a motivated individual obtains higher utility from becoming a non-pro�t manager, as compared to a unmotivated individual making the same choice, only when donations per non-pro�t are small enough, i.e. d=n < . both u�h and u � l are strictly increasing in donations per non-pro�t, d=n. however, when level of donations received by each non-pro�t rises above the threshold level (which here is equal to ), u�l surpasses u � h. the reason for this result essentially rests on the concavity of gi in ( ), combined with the altruism displayed by motivated non-pro�t managers in ( ). these two features translate into a payo¤ function of motivated non-pro�t managers, u�h, that is concave in d=n. on the contrary, unmotivated non-pro�t managers exhibit a payo¤ function, u�l, which is linear in d=n. this is because these agents only care about their private consumption, and hence they exploit the lack of monitoring in the ngo sector in order to always set wi = d=n. . equilibrium occupational choice let nh and nl denote henceforth the mass of non-pro�t managers of mh- and ml-type, respectively (the total mass of non-pro�t managers is then n = nh + nl). in equilibrium, the following two conditions must be simultaneously satis�ed: . given the values of nh and nl, each individual chooses the occupation that yields the higher level of utility, with some agents possibly indi¤erent between the two occupa- tions. . the allocation (nh;nl) must be feasible: (nh;nl) � ; � � � ; � : in this basic speci�cation of the model, for a given parametric con�guration, the equi- librium occupational choice will always be unique (except for one knife-edge case described in the footnote below). still, the type of agents (in terms of their pro-social motivation) who self-select into the non-pro�t sector will depend in an interesting manner on the speci�c parametric con�guration of the model. in what follows, we describe the main features of the two broad kinds of equilibria that may take place: an equilibrium where = nh < nl = n (which we refer to as �dishonest equilibrium�), and an equilibrium where = nl < nh = n (which we dub as �honest equilibrium�). the result in lemma does not crucially depend on the extreme assumption that mh = , and easily extends to any situation in which = ml < mh = m � : in that case, the mh�type sets w�i = �i ( �m)=( �m+ m), which in turn implies that at the optimum u�m = m mm( � ) ( �m+ m) �m( � ) � d n � �m( � ) = �(m; ) � d n � �m( � ) : therefore, noting that, for any vector (m; ) ( ; ]� ( ; ), the function �(m; ) satis�es � �(�) � , it follows that whenever d=n r [�(�)] =m( � ), then u�l r u�m. the above-mentioned two cases exclude the set of parametric con�gurations for which bn = n , where n is de�ned below in ( ). when bn = n , all individuals in the economy will be indi¤erent in equilibrium dishonest equilibrium an equilibrium in which the non-pro�t sector is populated exclusively by unmotivated in- dividuals arises when all motivated individuals prefer to found private �rms, whereas all unmotivated ones (weakly) prefer to become social entrepreneurs: u�h(n) < v � p(n) � u�l(n); where v �p(n) is given by ( ), u � h(n) by ( ), u � l(n) by ( ), and n = nl � = . lemma implies that for u�h(n) < u � l(n) to hold the non-pro�t sector should be su¢ciently small (i.e., n < bn), so that the level of donations received by each non-pro�t �rm turn out to be su¢ciently high. in addition, the condition v �p(n) � u�l(n) leads to: n � n � � + � : ( ) from ( ) we may observe that n < = . as a result, in a �dishonest equilibrium� it must necessarily be the case that n = nl = n , so that the unmotivated agents turn out to be indi¤erent between the for-pro�t and non-pro�t sectors. indi¤erence by ml-types leads a mass = � n of them to become private entrepreneurs, allowing thus "markets" to clear. notice, �nally, that u�h(n ) < v � p(n ) needs to be satis�ed, hence the crucial parametric condition leading to a �dishonest equilibrium� boils down to n < bn. honest equilibrium this type of equilibrium takes place when all unmotivated individuals prefer to found private �rms, whereas all motivated ones prefer (weakly) to be social entrepreneurs: u�l(n) < v �p(n) � u�h(n);where n = nh � = . lemma states that for u�h(n) > u � l(n) to hold, the non-pro�t sector should be su¢- ciently large in size: n > bn. the condition u�l(n) < v �p(n) requires that n > n (this is because the unmotivated agents prefer to stay out of the non-pro�t sector when the size of this sector is too large, as the available rents per manager are too low in that case). unlike in the previous case, in the �honest equilibrium� one cannot rule out the possibility of full sectorial specialization of the two motivational types of agents (i.e., in principle, an �honest equilibrium� may well feature nl = and nh = = ). across the two available occupations. moreover, because of that, there is actually equilibrium multiplicity, and the set equilibria is given by � n�h +n � l = n ; j � n�h � ; � n � l � . hereafter, for the sake of brevity, we skip this knife-edge case: for future reference, we denote with n the value of n that makes mh-types indi¤erent between occupations. from ( ) and ( ) we observe that: ( �n ) ��( � ) n � a � � : ( ) equilibrium characterization the following proposition characterizes the di¤erent kinds of equilibria that may arise, given the speci�c parametric con�guration of the model. proposition whenever a( + �) �� = , the equilibrium occupational allocation (n�h;n�l) is unique. the type of agents who manage the non-pro�t sector is determined solely by whether a( + �) �� is strictly larger or smaller than one: . if a( + �) �� > , in equilibrium there is a mass n� = n�l = n of non-pro�t �rms, all managed by ml-types. the mass of private entrepreneurs equals � n ; a mass of them are motivated, the remaining �n are unmotivated. . if a( + �) �� < , in equilibrium there is a mass n� = n�h = min � n ; of non- pro�t �rms, all managed by mh-types. moreover, if n � h = n (respectively, n � h = ); the mass of private entrepreneurs equals �n (respectively, ). when n � h = n , the mass of private entrepreneurs consists of a mass of unmotivated individual and a mass � n of motivated ones. instead, when n�h = , all private entrepreneurs are unmotivated. proof. see appendix a. proposition characterizes the three main types of equilibria that may arise in the model, depending on the speci�c parametric con�gurations. these three cases are depicted in figure , panels a, b, and c, respectively. this �gure portrays the indirect utilities of motivated and unmotivated agents in the non-pro�t sector (uh and ul, respectively) and of individuals in the private sector (y), as a function of the size of the non-pro�t sector, n. [insert figure about here] consider figure a, and suppose that the non-pro�t sector is initially of size zero. this situation is not an equilibrium, since both uh and ul lie above y when n = , and the utility di¤erential would attract both types of agents into the non-pro�t sector. as the size of the non-pro�t sector grows, the utility di¤erential shrinks for both types of agents. at the intersection of the uh-curve with y-curve, the motivated types are indi¤erent between the two sectors, but the ml-types still prefer the non-pro�t sector. therefore, the non-pro�t sector must still grow further. the equilibrium is only reached when the size of the non-pro�t sector equals n , at which point the unmotivated agents are indi¤erent between the pro�t and non-pro�t sectors while all motivated agents prefer the private sector. the situation plotted in figure b is analogous, except that the utility di¤erential for unmotivated types vanishes earlier than it does for the motivated ones, which serves as the basis for the honest equilibrium (with non-pro�t sector size equal to n ). finally, in the case depicted in figure c, once all the existing motivated agents have entered the non-pro�t sector, the utility di¤erential is positive even for the last entrant. the size of the non-pro�t sector is thus equal to and is rationed by the number of mh-agents. an interesting implication of proposition is that more productive economies (i.e., those with a relatively large a) tend to exhibit a �dishonest equilibrium�. this result rests on the fact that a larger a entails greater pro�ts to private entrepreneurs. hence, in equilibrium, a larger amount of donations to any non-pro�t �rm (�i) are needed to compensate for the higher opportunity cost of managing a non-pro�t �rm (i.e., the fact of not becoming a private entrepreneur). this result has interesting implications for an initially poor economy on a positive growth path. as the productivity parameter a increases from an initial level below =( + �) �� , some non-pro�t mh-type managers start leaving the non-pro�t sector to found their private �rms, which are becoming increasingly pro�table. importantly, while this process takes place, the level of donations received by each of the remaining non-pro�ts �rms will also grow. as private productivity keeps rising over time, a will eventually surpass the threshold =( + �) �� , and the economy will experience a radical transformation in their non-pro�t sector: all motivated managers leave the non-pro�t sector to found a private �rm, while a mass n of unmotivated agents leave the private sector to found non-pro�t �rms. a similar intuition applies to the e¤ect of a higher warm-glow utility from giving; that is, a greater �. this yields a larger amount of total donations, d, for a given mass of non-pro�ts a rise in � could be caused, for instance, by the e¤ects of stronger social norms of giving, or by an increase in the social prestige associated with observable giving by private-sector managers. n, making the non-pro�t sector relatively more attractive to unmotivated agents than to motivated ones. again, beyond some threshold of �, this in turn will lead to a reshuing of the motivational composition of the non-pro�t sector, analogous to the one described just above for an increase in a. in terms of policy implications, the results obtained above imply that the value-added of betteraccountability for theperformanceof thenon-pro�t sector increaseswiththeaggregate generosity in the economy. in other words, donations and accountability are complementary inputs in the aggregate production function of the non-pro�t sector. a larger d �either resulting from higher aggregate private income or larger �� corresponds to an increase of only one input into the aggregate production function of the non-pro�t sector. however, such a rise in d, without an accompanying increase in the other input (i.e., accountability), may turn out to be actually negative for the functioning of the non-pro�t sector. . e¤ect of foreign aid on the equilibrium allocation so far, all donations in our model were generated (endogenously) within the economy. how- ever, foreign aid is also a crucial source of revenue for non-pro�ts organizations and ngos in many developing countries. in fact, a growing share of foreign aid is being channeled through the ngos. for instance, data from the united states shows that over per cent of u.s. overseas development funds �ows through ngos (barro and mccleary ). international aid agencies as well have been increasingly preferring ngos to public-sector channels: e.g., whereas between and , a tiny per cent of world bank projects went through ngos, by this share exceeded per cent (hudock ). as kanbur ( ) argues, the rise of ngos during the s was one of the key changes in the functioning of the foreign aid sector. what would be the e¤ect of a rise in foreign aid on the motivational composition and performance of the non-pro�t sector of the recipient economy? in this subsection, we ap- proach this question. to do so, we slightly modify the previous model to allow an injection of amount � > of foreign aid (outside donations) into the economy. foreign aid represents an exogenous increase in the total amount of donations available to the national non-pro�t sector. donations collected by a non-pro�t �rm now become: d n = �a( �n)� +� n : ( ) asdoneabove inlemma , we�rstpindownthethreshold bn suchthat, foralln > bn the utility obtained by unmotivated non-pro�t managers dominates that obtained by motivated non-pro�t managers. lemma (i) whenever � � � , there exists a threshold bn � such that u�h(n) r u�l(n) i¤ n r bn; the threshold bn is strictly increasing in �, and lim�! bn = . (ii) whenever � > , u�h(n) , hence @ bn=@� > : also, given that � ( bn) > and �( ) = , it follows that, for any � � � , the solution of �( bn) = � must necessarily satisfy bn � . the second part follows directly from observing that when � > , the right-hand side of ( ) is strictly greater than unity for all < n � . the �rst result in lemma essentially says that the set of values of n for which the inequality u�h(n) < u � l(n) holds �which is given by the interval ( ; bn)� expands as the amount of foreign aid � increases. the second result states that when foreign aid is su¢- ciently large, the dominance relation u�h(n) < u � l(n) becomes valid for any feasible value of n. the injection of foreign aid thus enlarges the set of parameters under which the economy featuresanequilibriumwithunmotivatednon-pro�tmanagers (�dishonest equilibrium�). the proposition below formalizes this perverse e¤ect of foreign aid. for brevity, we restrict the analysis only to the more interesting case, in which a( + �) �� < . it is useful to denote by n the level of n for which y(n) in ( ) equals one; that is, n � �a �� : ( ) in addition, in order to disregard situations in which n � fails to exist, we henceforth set the following upper-bound on a: assumption a � : note that if a > , then the condition a( + �) �� < for an �honest equilibrium� in proposition could never hold, and the model would always deliver �by construction� a �dishonest equilibrium�. another way to avoid the problem of obtaining a �dishonest equilibrium� by construction is to assume that the production function of private entrepreneurs is given by y(n), with y (n) > ; y (n) < , y( ) = and y( ) = . notice that all these properties are satis�ed by ( ), except for y( ) = , which in ( ) is actually y( ) = a. intuitively, what is needed to give room for an �honest equilibrium� is that y(n) � for some n � . assumption ensures this is always the case. proposition let a( + �) �� < so that when � = the economy features an �honest equilibrium�. let also � � �a ��( + �); and note bn = n when � = � : . if ��a > , there exist two thresholds, �a > � > , such that: (a) when � � < � , all non-pro�t �rms are managed by mh-types: < n�h < and n�l = , where n � h is strictly increasing in �. (b) when � < � � �a, all non-pro�t �rms are managed by ml-types: < n�l � and n�h = , where n � l is strictly increasing in � whenever n � l < . (c) when � > �a, non-pro�t �rms are managed by a mix of types with ml-type majority, namely: n�l = and < n�h < , where n�h is strictly increasing in � and lim�!�a n � h = . . if ��a < , there are two thresholds, � > �b > , such that: (a) when � � � �b, all non-pro�t �rms are managed by mh-types: < n�h � and n�l = , where n � h is strictly increasing in � whenever n � h < . (b) when �b < � � � , non-pro�t �rms are managed by a mix of types with mh- type majority, namely: n�h = and < n�l < , where n�l is strictly increasing in � and lim�!�b n � l = . (c) when � > � , non-pro�t �rms are managed by a mix of types with ml-type majority, namely: n�l = and < n�h < , where n�h is strictly increasing in � and lim�!� n � h = n � > . proof. see appendix a. proposition describes the e¤ects of changes in the amount of foreign aid � on the equilibrium allocation of an economy which, in the absence of any foreign donations, would display an �honest equilibrium�. the most interesting results arise when a( + �) �� < < ��a. in this case, when foreign aid is not too large ( � � < � ), the non-pro�t sector continues to be managed only by motivated agents. however, when the level of donations surpasses the threshold � , unmotivated agents start being attracted into the non-pro�t sector due to the greater scope for rent extraction. interestingly, for any � < � � �a, the economy experiences a complete reversal in the equilibrium occupational choice: all mh- types choose the private sector, while the non-pro�t sector becomes entirely managed by ml-types. finally, when � > �a, foreign aid becomes so large that the non-pro�t sector starts attracting back some of the mh-types in order to equalize the returns of motivated agents in the for-pro�t and non-pro�t sectors. notice, however, that when � > �a the mass of non-pro�ts run by unmotivated agents is still larger than the mass of non-pro�ts managed by mh-types. [insert figure about here] figure depicts the above-mentioned results when a( + �) �� < < ��a. the solid lines represent u�h(n) and u � l(n) when � = , the dashed lines shows non-pro�t managers� payo¤s when � < � � �a, and the dotted lines plots those payo¤s when � > �a. a gradual injection of foreign aid from � = to � = � initially has no e¤ect on the motivational composition of the non-pro�t sector, given that the utility di¤erential between the two sectors remains negative for the unmotivated types. beyond the amount of aid � = � , this utility di¤erential becomes positive for the unmotivated types, whereas it turns negative for the motivated ones. at that point, the motivational composition of the non-pro�t sector is completely reversed. further increases in foreign aid have no e¤ect on the non-pro�t sector�s output, up to the point � = �a. there, all the unmotivated agents have moved into the non-pro�t sector and thus its size equals . from then on, further injections of aid (beyond �a) start to attract back some motivated agents into the non-pro�t sector, and the motivational composition of the sector therefore improves. a key corollary that stems from proposition refers to the total output of the non-pro�t sector, g, at di¤erent values of �. bearing in mind that only motivated non-pro�t managers use donations to produce the mission-oriented output gi, an implication of proposition is thatg(�) is non-monotonic in�. inparticular, in thecasewherea( + �) �� < < ��a, non-pro�t output grows initially with the amount of foreign aid, up to the level when � = � when it reaches g(� ) = n; this is the enhancing e¤ect of foreign donations when the non- pro�ts are managed by motivated managers. however, for � < � � �a, the motivation in the non-pro�t sector gets completely "polluted" by the presence of unmotivated managers, and g(�) drops suddenly to zero. finally, when foreign donations rise beyond �a, non- pro�t output begins to grow again (starting o¤ from g = ), as some of the donations will end up in the hands of mh-types. this non-monotonicity is illustrated by figure , which depicts the total output of the non-pro�t sector as a function of foreign aid in�ow. [insert figure about here] similar results are obtained when ��a < . in this case, g(�) increases monotonically with � for all � < � , reaching g(� ) = . however, as soon as � rises above � , aggregate non-pro�t output falls discretely to n � . thereafter, for all � > � , g(�) grows again monotonically with �, starting from g(�) = n � . our analysis con�rms some of the concerns raised by critiques of foreign aid, by pointing out at one precise mechanism through which the negative e¤ect of aid operates: the encour- agement of unmotivated agents to replace motivated ones in the ngo sector. for instance, dambisa moyo writes in her book entitled dead aid (moyo ): "donors, development agencies and policymakers have, by and large, chosen to ignore the blatant alarm signals, and have continued to pursue the aid-based model even when it had become apparent that aid, under whatever guise, is not working... foreign aid does not strengthen social capital - it weakens it. by [...] encouraging rent-seeking behavior, siphoning o¤ scarce talent from the employment pool [...] aid guarantees that in most aid-dependent regimes social capital remains weak and the countries themselves poor" (pp. , ) note that our mechanism is quite di¤erent from the several arguments previously raised concerning the perverse e¤ects of foreign aid on the functioning of the public sector (for example, due to higher corruption, break-up of accountability mechanisms of elected o¢- cials, triggering ethnic-based rent-seeking; see svensson ). our model shows that even when foreign aid is channeled through the ngo sector (therefore, by-passing the public bu- reaucracy) perverse e¤ects might still arise, since more massive aid in�ows may lead to a worsening of motivational composition of the ngo sector in the recipient country. in that regard, our results also help shedding light on the so-called micro-macro paradox found in the empirical foreign aid literature (mosley ). this paradox refers to the fact that, at the microeconomic level, there are numerous studies that �nd the positive e¤ect of foreign-aid �nanced projects on measures of welfare of bene�ciaries, while at the aggregate level most studies actually fail to �nd a signi�cant positive e¤ect. our model explains this paradox as follows: when aid in�ows are small (or, alternatively, when you hold the motivational composition of the ngo sector constant) the general equilibrium e¤ect described in our model becomes negligible (or, alternatively, disappears altogether). under such circumstances, empirically, one �nds a positive e¤ect of aid projects. however, when aid in�ows are su¢ciently large (e.g. when the well-functioning micro-level projects are scaled up), the general equilibrium e¤ects kick in, and the motivational adverse selection e¤ect may neutralize the positive e¤ect found at the micro level. . taxes and public �nancing of non-pro�ts in most economies, an important part of non-pro�ts� revenues comes from public grants �nanced by taxes. this raises two questions: what is the e¤ect of partial public �nancing on the motivational composition and size of the non-pro�t sector? can public �nancing generate an improvement on the composition of the non-pro�t sector, as compared to the decentralized equilibrium, and if so, how should such �nancing be designed? in this section, we address these questions by adding a set of public policy variables into our basic model. let the government impose a proportional tax on income in the for-pro�t sector and use its proceeds as (unconditional) grants to non-pro�ts. thus, the payo¤s of individuals in the private sector becomes: v �p = ( � t)y; ( ) where y is as stated in ( ). the level of donations collected by each non-pro�t in this case are given by: �i = d n = private donationsz }| { � ( � t)( �n)y + public grantz }| { t( �n)y n : ( ) public �nancing via such a tax/grant system alters occupational choices of individuals via two distinct channels. on the one hand, we can see in ( ) that taxation lowers returns in the private sector. on the other hand, as the public sector donates back all the taxes it collects while the private sector only gives a fraction � of its net income, �i in ( ) increases with the tax rate t. both channels, ceteris paribus, turn the non-pro�t sector more attractive to all individuals. however, within our general equilibrium framework, the key issue is whether public �nancing increases the attractiveness of the non-pro�t sector relatively more for altruistic or for self-interested individuals. to study the more interesting case, let us focus on a setting where our basic economy (without public �nancing) would give rise to a �dishonest equilibrium�: a( + �) �� > : [insert figure about here] consider now an increase in taxes, with the transfer of all the proceeds to nonpro�ts as grants. for such policy to induce a motivational improvement in the nonpro�t sector, it is crucial that, in the new equilibrium (after taxes), the dishonest individuals who were initially managing the nonpro�t sector switch occupations and move to the private sector. this will occur only if the policy attracts enough motivated agents from the private sector into the nonpro�t sector, such that this entry su¢ciently dilutes the amount of funds per non-pro�t �rm, even after taking into account the larger total funding of the non-pro�t sector as a whole. the proposition below formally proves that such a tax/grant policy exists. proposition for a( + �) �� = + �, where < � < �, there exist a feasible range of tax rates [t;t], where t > and t � ( � �)=( � �), such that when t [t;t] an �honest equilibrium� arises. figure (panel a) plots the equilibrium regions for di¤erent combinations of values of a and t (see appendix a for the derivation of the equilibrium regions). there are four di¤erent regions. for combinations of relatively low values of a and t, the model features an �honest equilibrium� where the non-pro�t sector is fully managed by motivated agents. on the other hand, given a certain level of t, for su¢ciently high levels of a we have a �dishonest equilibrium�. notice that when t = , the boundary between these two regions is given by a = =( + �) ��, as previously stated in proposition . in addition, with public �nancing, two new equilibrium regions arise: one with a mixed-type equilibrium with a fraction of motivated agents in the non-pro�t sector larger than one half (f > : ), and one with a mixed-type equilibrium with f < : . these two types of equilibria occur when the tax rate is su¢ciently large, while the former also requires that a is su¢ciently small and the latter that a takes intermediate values. a crucial feature of figure is that threshold of a splitting the �honest� and �dishonest� equilibrium regions is increasing in t (up to the point in which t = t). as a consequence, there exist situations in which introducing public funding of non-pro�ts via (higher) taxes on private incomes can make the economy switch from a �dishonest� to an �honest� equilibrium. this is depicted in figure (panel b) by the dashed line arrow. this result rests on a subtle general equilibrium interaction. consider an economy with no taxes that is on the �dishonest equilibrium� region, located, for example, at point z. at z, all mh-types prefer the private sector, while ml-types are indi¤erent between the non-pro�t sector. since a higher tax rate makes the non-pro�t sector more attractive, by su¢ciently raising t we can make all mh-types prefer non-pro�t sector as well. however, when all motivated agents switch to the non-pro�t sector, the value of n will rise and the returns in this sector will accordingly decrease. when t lies within the interval [t;t], the new equilibrium allocation induced by the increase in t leads to an increase in total funding of the non-pro�t sector but reducing the value of per-organization funding (�i) strongly enough such that only motivated agents are attracted to the non-pro�t sector. it is important to note that this motivational reshuing will not occur if the public �nancing policy is too small. in particular, a mild increase in taxes will actually make things even worse for the non-pro�t sector, as this would only raise the total funding of the non-pro�t sector without altering its motivational composition. graphically, this would corresponds to any increase in taxes below the level t in figure (panel b). a well-designed tax/grant public policy will then to increase the variety (number) of non-pro�t �rms enough so as to simultaneously reduce the per-nonpro�t �nancing (made of voluntary donations and the grant). what are the implications of this insight for public policies towards the non-pro�t sector? in our setting, exactly like the donors, the policy- maker is subject to the same asymmetric information regarding the motivational type of each speci�c agent. however, the policy-maker can change the relative returns in the two sectors so as to induce the motivational "cleansing" of the nonpro�t sector by scaling-up funding through expanding the extensive margin (i.e., inducing a greater number of non- pro�t organizations), while simultaneously shrinking the intensive margin (i.e., reducing per-organization funding level). in other words, in our setting "small is indeed beautiful": starting from a dishonest equilibrium, the policy-maker should make sure that the funding received by each non-pro�t �rms decreases. in our general equilibrium framework, this is hence, in the equilibrium at z, a part of the ml-types will choose the private sector and the other part will found non-pro�t �rms. notice thatall this implies that, in thenewequilibrium, the totalmassofnon-pro�t�rmsmustnecessarily be larger than in z, since from ( ) it follows that �i will grow with t for a given level of n. in other words, after t is raised to a level within [t;t], a mass n�l of unmotivated non-pro�t managers will be replaced by a mass n�h of motivated non-pro�t managers, where n � h > n � l. achieved by inducing a massive entry of new non-pro�t managers. in terms of actual implementation, our result imply that it may be advisable to give starting grants to new nonpro�ts, possibly even at the expense of cutting the �nancing to the existing larger ones. for instance, consider the recent proposals to do "philanthropy through privatization" (see salamon ), which consists in returning part of proceeds from the privatization of public sector assets to foundations and charities. our analysis suggests that this policy would work correctly only if the way these proceeds are used is such that they are scattered through a multitude of small organizations, rather than concentrating them on a few large nonpro�ts: the latter risks worsening the motivational composition of the sector by attracting unmotivated agents, whereas the former ensures that the returns in the non-pro�t sector remain low enough to attract only highly motivated managers. endogenous fundraising e¤ort in the basic model in section , we have assumed that total donations are split (quite me- chanically) between all non-pro�t �rms. it is well known, however, that non-pro�ts compete for donations and engage actively in fundraising. for instance, in his analysis of the hu- manitarian relief ngos, de waal ( ) describes the so-called gresham�s law of the ngo sector: "[an organization that is] most determined to get the highest media pro- �le obtains the most funds [...] in doing so it prioritizes the requirements of fundraising: it follows the tv cameras, [...] engages in picturesque and emotive programmes (food and medicine, best of all for children), it abandons scruples about when to go in and when to leave, and it forsakes cooperation with its peers for advertising its brand name." similarly, in his poignant account of the development aid industry, hancock ( ) de- scribes the example of world vision (a large u.s.-based ngo), aggressively competing for donors in the australian market with local religious organizations: "on december , unable to resist the allure of ethiopian famine pic- tures, world vision ran an australia-wide christmas special television show calling on the public in that country to give it funds. in so doing it broke an explicit understanding with the australian council of churches that it would not run such television spectaculars in competition with the acc�s traditional christmas bowl appeal. such ruthless treatment of �rivals� pays, however: the american charity is, today, the largest voluntary agency in australia." in this section, we relax the assumption of �xed division of donations by incorporating the endogenous fundraising choice by non-pro�ts. in terms of the private sector, we keep the same structure described in section . . the main di¤erence is that now non-pro�t managers can in�uence the share of funds they obtain from the pool of total donations by exerting fundraising e¤ort. more precisely, we assume that each non-pro�t manager i is endowed with one unit of time, which she may split between fundraising and working towards the mission of her non-pro�t organization (project implementation). fundraising e¤ort allows the non-pro�t manager to attract a larger share of donations (from the pool of aggregate donations) to her own non-pro�t, while implementation e¤ort is required in order to make those donations e¤ective in addressing the non-pro�t�s mission. we denote henceforth by ei � the e¤ort exerted in fundraising and by &i � the implementation e¤ort. the time constraint implies that ei + &i [ ; ]. as before, the non-pro�t manager collects an amount of donations �i from the aggregate pool of donations d. one part of �i is used to pay the wage of non-pro�t manager wi, while �i �wi is used as input for the non-pro�t�s production. in this section, in the sake of algebraic simplicity, we assume that the output of a non-pro�t �rm is linear in undistributed donations, namely: gi = (�i �wi)&i: ( ) notice, however, that ( ) implies that undistributed donations (�i�wi) and implementation e¤ort (&i) are complements in the production function of the non-pro�t. we assume that aggregate fundraising e¤ort does not alter the total pool of donations channeledto thenon-pro�t sector, d. however, the fundraisinge¤ort exertedbyeachspeci�c non-pro�t manager does a¤ect how a given d is divided among the mass of non-pro�t �rms, n. in other words, we model fundraising as a zero-sum game over the division of a given d. formally, we assume that �i = d n � ei e = �a( �n)� n � ei e ; ( ) where e denotes the average fundraising e¤ort in the non-pro�t sector as a whole. again, non-pro�t managers derive utility from their own consumption and from their contribution towards their mission, with weights on each of two sources of utility determined by the agent�s level of pro-social motivation, mi. in addition, we assume the total e¤ort exerted by non-pro�t managers entails a level of disutility which depends on the agent�s intrinsic pro-social motivation: ui(wi;gi) = w �mii g mi i mmii ( �mi) �mi � ( �mi)(ei + &i) , where mi fmh;mlg: since mh = , in the optimum, motivated non-pro�t managers will always set w � h = and e�h+& � h = . the exact values of e � h and & � h are determined by the following optimization problem e�h � argmax ei [ ; ] : gi = d n ei e ( �ei) ; with &�h = �e�h. the above problem yields, e�h = & � h = ; ( ) which in turn implies that an mh-type non-pro�t manager obtains a level of utility given by u�h = e d n = e �a( �n)� n : ( ) with regards to unmotivated non-pro�t managers, again, they will always set w�l = �i. in addition, since unmotivated agents care only about their private consumption and &i is only instrumental in producing non-pro�t output, in the optimum, they will always set &�i = . as a consequence, the level of e � l will be determined by the solution of the following maximization problem e�l � argmax ei [ ; ] : wi = d n ei e �ei; which, given the linearity of both the bene�t and the cost of e¤ort, trivially yields e�l = ( , if e� d=n < ; , if e� d=n � : ( ) as a result, the utility that an unmotivated agent obtains from becoming a non-pro�t manager is u�l = max � d n e � ; � : ( ) note that the indirect utility of the unmotivated agent decreases, as before, with the size of the non-pro�t sector; however, it reaches zero at an interior value, whereas in the basic model it reached zero only when n = . this is because now donations are not simply "manna from heaven" but must be obtained through exerting costly e¤ort. for a su¢ciently large size of the non-pro�t sector, the level donations per non-pro�t �rm that can be obtained through fundraising e¤ort is just too small to justify the necessary e¤ort cost. this means that an unmotivated agent will choose to stop competing for donations if the number of non-pro�ts �rms n reaches a certain critical level. (beyond such critical level of n unmotivated managers would optimally choose to exert no e¤ort and collect zero donations, which accordingly yields u�l = ). honest equilibrium in an honest equilibrium all non-pro�t managers are of mh-type and set e � h = : . denoting by n�h the equilibrium mass of non-pro�t managers in an honest equilibrium, this implies that they will end up raising ��h = �a( �n�h) � n�h : ( ) recalling ( ), ( ) and ( ), we can observe that an honest equilibrium exists if and only if ��h � when motivated agents are indi¤erent between the non-pro�t and the for-pro�t sectors. hence, an honest equilibrium exists if and only if �a( �n�h) � n�h � ; where n�h solves u � h(n = n � h;e = : ) = v � p(n = n � h). proposition , presented below, shows that the necessary and su¢cient parametric condition for an honest equilibrium to exist is that a � =( + �) ��, and that this equilibrium is unique. dishonest equilibrium in a dishonest equilibrium all non-pro�t managers are of ml-type and set e � l = . denoting now by n�l the equilibrium mass of non-pro�t managers in a dishonest equilibrium, this implies that they will end up raising ��l = �a( �n�l) � n�l : ( ) using again ( ), ( ) and ( ), it follows that a dishonest equilibrium exists if and only if ��l > when unmotivated agents are indi¤erent between sectors. therefore, a dishonest equilibrium exists if and only if �a( �n�l) � n�l � ; where n�l solves u � l(n = n � l;e = ) = v � p(n = n � l). proposition shows that the nec- essary and su¢cient parametric condition for the existence of a dishonest equilibrium is a � [ =( + �)] ��, and that this equilibrium is unique. mixed-type equilibrium in a mixed-type equilibrium all agents are indi¤erent across occupations and the non-pro�t sector is managed by a mix of mh and ml types. that is, a mixed-type equilibrium is characterizedbyu�h(n �) = u�l(n �) = v �p(n �), wheren� = n�l+n � h and < n � l;n � h � = . equality among ( ) and ( ) requires that average fundraising e¤ort satis�es emixed = : � (d=n), which in turn means that u�h(n�) = u�l(n�) = . the returns in the private sectormust thenalsobeequal toone, which, using( ), implies that inmixed-typeequilibrium the total mass of non-pro�ts must be equal to n� = � a �� : in addition, since e�h = while e�l = , then the fact that emixed = : � (d=n) together with n� = � a �� pin down the exact values of n�l and n � h, so as to ensure indi¤erence across the two occupations by all agents. proposition shows that the necessary and su¢cient parametric condition for the existence of a mixed-type equilibrium is =( + �) �� < a < [ =( + �)] �� , and that this equilibrium is unique. equilibrium characterization with fundraising e¤ort the following proposition characterizes the type of equilibrium that arises, given the speci�c parametric con�guration of the model with fundraising e¤ort. proposition the type of equilibrium allocation that arises is always unique and depends of the speci�c parametric con�guration of the model: . if a � =( + �) ��, the economy exhibits an �honest equilibrium� with n� = n�h = �=( + �). all non-pro�t managers exert the same level of fundraising and project implementation e¤ort: e�h = & � h = : . . if a � [ =( + �)] ��, the economy exhibits a �dishonest equilibrium� with n� = n�l, where �=( + �) < n�l < �=( + �). all non-pro�t managers exert the same level of fundraising and project implementation e¤ort: e�l = and & � l = . . if =( + �) �� < a < [ =( + �)] �� , the economy exhibits a mixed-type equilibrium with a mass of non-pro�t �rms equal to n�mixed = �a ��, where n�h = h �a �� ( + �= ) i ; and n�l = a �� ( + �)� : ( ) motivated non-pro�t managers set e�h = & � h = : , while unmotivated agents set e � l = and &�l = : the average level of fundraising e¤ort is then: emixed = �a �� a �� : ( ) proof. see appendix a. [insert figure about here] the result of an �honest equilibrium� when a � =( + �) �� is the analogous to that one previously obtained in the basic model (as shown graphically in figure , panel a). similarly, when a � [ =( + �)] �� the model features a pure �dishonest equilibrium� (see figure , panel b). however, in this alternative setup, we can observe the set of parameters under which such an equilibrium arises is actually smaller than in the basic model in section . moreover, a novelty of this alternative setup is that for the intermediate range of a there exists a "mixed-type" equilibrium (one under which the non-pro�t sector is populated by both types of agents). intuitively, the necessity of competition for donations reduces the utility of the unmotivated agents. as a consequence, this creates parameter con�gurations under which, in the absence of fundraising competition the non-pro�t sector would be popu- lated only by unmotivated agents, whereas in the presence of competition a fraction of them moves into the private sector (and are in turn replaced by a fraction of motivated agents). it is interesting to compare the �ndings of this model to those of aldashev and verdier ( ), where more intense competition for funds leads to higher diversion of donations by non-pro�tmanagers. thisoccursbecausewhenagentshavetospendmoretimeraising funds, less time is then left to be devoted to working towards the non-pro�t mission, and thus the opportunity cost of diverting money for private consumption falls. in that model, all agents are intrinsically identical, and thus the issue of more intense competition lies in aggravating a moral hazard problem. here, instead, the existence of motivationally heterogeneous types implies that the main problem is one of adverse selection, and, interestingly, a more intense competition for funds mitigates the severity of this adverse selection problem. extensions the basic model of the previous section made two particularly strong assumptions. the �rst � a behavioral one � is that donations by private entrepreneurs were unrelated to their degree of altruism. the second � an institutional one �, that donors were completely unaware of the motivational problems in the non-pro�t sector and enjoyed giving independently of who is actually managing the non-pro�t sector. in this section, we present two extensions of the model that relax these assumptions. . extension : pure and impure altruism the model presented in section assumes that all private entrepreneurs (regardless of their pro-social motivation) donate an identical fraction of their income to the non-pro�t sector. however, if warm glow giving is actually the result of some sort of altruistic behavior, it seems more reasonable to expect the propensity to donate out of income to be increasing in the degree of pro-social motivation. here, we modify the utility function in ( ) by letting the propensity to donate be type-speci�c (�i) and increasing in mi. in particular, we now assume that �i = �h ( ; ] when mi = mh, whereas �i = �l = when mi = ml. the key di¤erence that arises when �i is an increasing function of mi is that, for a given value of � n, the total level of donations will depend positively on the ratio ( � nh)=( � n). intuitively, the fraction of entrepreneurial income donated to the non-pro�t sector will rise with the (average) level of warm-glow motivation displayed by the pool of private entrepreneurs. to keep the analysis simple, we abstract from fundraising e¤ort, and assume again that the mass of total donations are equally split by the mass of non-pro�ts. in addition, we let the payo¤ functions by motivated and unmotivated non-pro�t entrepreneurs be given again by ( ) and ( ), respectively. donations collected by a non-pro�t is given by: d n = �h a � �nh � ( �nh �nl) �� (nh +nl) : ( ) when the total amount of donations to the non-pro�t sector depends positively on the fraction of pro-socially motivated private entrepreneurs, the model exhibits multiple equi- notice that, in the speci�c case in which �h = , the utility functions in the private sector and the non-pro�t sector would display the same structure for both mh- and ml-types: for the former, all the utility weight is being placed on pro-social actions (either warm-glow giving or producing gi); for the latter, all the utility weight is being placed on private consumption. libria. the main reason for equilibrium multiplicity is that, when �i is increasing in mi, the ratio between u�h and u � l does not depend only on the level of n � as it was the case with ( ) and ( ) in section � but, looking at ( ), it follows that it also depends on how n breaks down between nh and nl. such dependence on the ratio nh=nl generates a positive interaction between the incentives by ml-types to self-select into the non-pro�t sector and the self-selection of mh-types into the private sector. the next proposition deals with this issue in further detail. proposition let �i = �h ( ; ] for mi = mh and �i = �l = for mi = ml. then, . unique �honest equilibrium�: if a < ( � �h= ) ��, the equilibrium in the economy is unique, and characterized by �h=( + �h) < n � h < and n�l = : . unique �dishonest equilibrium�: if a > [( + �h)=( + �h)] �� , the equilibrium in the economy is unique, and characterized by n�l = �h= and n � h = : . multiple equilibria: if ( � �h= ) �� < a < [( + �h)=( + �h)] ��, there exist three equilibria in the economy, a) an �honest equilibrium� where �h=( + �h) < n � h < and n�l = ; b) a �dishonest equilibrium� where n�l = �h= and n � h = ; c) a �mixed-type equilibrium� where n�h = � �a =( ��) �h and n�l = [ �a =( ��)]( +�h) �h � . proof. see appendix a. proposition shows that for a su¢ciently small the economy will exhibit an �honest equilibrium�, whereas when a is su¢ciently large the economy will fall in a �dishonest equi- librium�. these two results are in line with those previously presented in proposition . however, proposition alsoshowsthat thereexistsan intermediate range, ( � �h= ) �� < a < [ � �h=( + �h)] ��, in which the economy displays multiple equilibria. for those intermediate values of a, the exact type of equilibrium that takes place will depend on how agents� expectations coordinate. if agents expect a large mass of mh-types to choose the non-pro�t sector (case a above), then the total mass of private donations (for a given n) will be relatively small, sti�ing the incentives of ml-types to become non-pro�t managers. in the speci�c cases where a = ( ��h= ) �� or a = [ � �h=( + �h)] ��, the �mixed-type equilib- rium� described below disappears, while the other two equilibria remain. conversely, if individuals expect a large mass of mh-types to become private entrepreneurs (case b above), the value of d (for a given n) will turn out to be large, which will enhance the incentives of ml-types to enter into the non-pro�t sector more than it does so for mh-types. notice that the range of productivity a for which multiple equilibria occur increases with the (relative) generosity of the motivated individuals, �h. this is depicted in figure : the range of values of a subject to multiple equilibria vanishes as �h approaches zero. [insert figure about here] finally, there is also the possibility of intermediate consistent expectations (case c above), in which both motivated and unmotivated agents are indi¤erent across occupations, and a mix of ml- and mh-types share the non-pro�t sector. . extension : conditional warm glow giving so far, we have assumed that mh-type private entrepreneurs donate a fraction �h of their income simply because they enjoy the act of giving. this is the essence of warm glow giving and impure altruism. however, if these agents were actually motivated by pure altruism, then motivated entrepreneurs would not be willing to donate money to non-pro�ts managed by ml types, and a �dishonest equilibrium� could never arise in our model. in this subsection, we relax to some extent the assumption of impure altruism, although we do not go all the way to assuming pure altruism by private entrepreneurs with rational expectations. more precisely, we extend our model in section . to allow �h to rise with the fraction of motivated non-pro�t managers, by postulating that mh-type private entrepreneurs have the following utility function: vh(c;d) = � e� e�h h ( �e�h) � e�h � � c � e�h d e�h, where e�h = f �h and f � nh nh +nl : ( ) the utility function ( ) displays conditional warm glow altruism, in the sense that the intensity of the warm glow giving parameter (e�h) is linked to the likelihood that the donation ends up in the hands of a motivated non-pro�t manager. we must stress that our desire to maintain some impure altruism component is not just due to mod- elling convenience, but also for consistency: andreoni ( ) shows that under pure altruism, voluntary contributions to public good provision would vanish when the number of donors is su¢ciently large. when pro-socially motivated private entrepreneurs are characterized by ( ), the level of donations obtained by a non-pro�t �rm will be given by: d n = �h a � �nh � nh ( �nh �nl) �� (nh +nl) : ( ) proposition let the propensity to donate be given by e�i = f �i; where �h ( ; ], �l = and f � nh=(nh +nl). then, de�ning � � [( + �h)=( + �h)] �� : . if a � �, in equilibrium, n�h = �h(a) and n�l = , where: @�h=@a < , and lima!� �h (a) = �h=( + �h). . if � < a � , in equilibrium, < n�h < and < n � l < , with n�h + n � l =� �a =( ��) � . in particular, n�h = nh(a) and n � l = nl(a), where: nh(a) = � s � � �a =( ��) � �h , nl(a) = � �a =( ��) � �nh: moreover, when � < a � , the fraction of pro-socially motivated non-pro�t managers is strictly decreasing in a; that is, @f=@a < . proof. see appendix a. proposition states that when warm glow weights depend on the fraction of motivated agents within the pool of non-pro�t managers, the possibility of multiplicity of equilibria disappears. the responsiveness of e�h to f in ( ) counterbalances the e¤ect that a larger mass of mh-type entrepreneurs has on total donations in ( ), and thus neutralizes the source of interaction that leads to multiple equilibria in proposition . in addition, condi- tional warm glow altruism removes the possibility that the non-pro�t sector is managed fully by unmotivated agents, since in those cases motivated private entrepreneurs would refrain from donating any of their income. nevertheless, conditional warm glow altruism does not preclude the fact that the non-pro�t sector may end up being partly managed by ml-types. this occurs when a is su¢ciently large, which is in line again with the results of the baseline model in proposition . furthermore, proposition shows that the fraction of dishonest non-pro�t managers is monotonically increasing in a. discussion in this section, we discuss several key assumptions and modelling choices on which our analysis is built, as well as the robustness of our results to varying them. . decreasing returns in the non-pro�t sector one key assumption of the model is the decreasing returns in the non-pro�t sector ( < < ). it underlies the single-crossing result (lemma ). the nature of the functioning of the non-pro�t sector organizations indicates that this assumption is appropriate. as non-pro�t organizations are de�ned by their missions, the fundamental scarce resource of these organizations is motivated labor, i.e. individuals who believe into (or aligned with) the mission of a particular non-pro�t. the practitioners of the sector underline that �nding such people and expanding the sta¤ of the organization is often extremely di¢cult, mainly because of the existing variety of missions and organizations (this has also been highlighted by the matching-to-mission model of besley and ghatak, ). a fundamental di¤erence of this sector with respect to for-pro�t �rms is that money cannot easily buy time (but time can buy money, through fundraising activities). thus, when the funding of a non-pro�t expands, while its motivated labor remains �xed, the diminishing marginal product of funds guarantee that the returns are decreasing. for instance, robin- son ( ) notes, concerning development non-pro�t working in rural areas, that "ambitious attempts to expand or replicate successful projects can founder on the paucity of appropri- ately trained personnel who are experienced in community development" (p. ). similarly, hodson ( ) states that "upgrading the management capability [of a development non-pro�t] usually implies new talent. unfortunately, the story-book scenario under which the orig- inal team continues to develop its management capability at a rate su¢cient to cope with rapid growth rarely comes true..." (p. ) in addition, beyond a certain scale, the successful projects of non-pro�ts have to rely on public infrastructure and employees (for instance, at a national level). as underlined by edwardsandhulme( ), this immediately clasheswith theusual government ine¢ciencies of developing countries: "e¤ective development work on a sustainable and signi�cant scale is a goal which has eluded [development non-pro�ts, because of] the failure to make the right linkages between their work at micro-level and the wider systems and struc- tures of which they form a small part. for example, village co-operatives are undermined by de�ciencies in national agricultural extension and marketing sys- tems; �social-action groups� can be overwhelmed by more powerful political inter- ests within the state or local economic elites; successful experiments in primary health care cannot be replicated because government structures lack the ability or willingness to adopt new ideas..." (p. ) secondly, the type of tasks that a non-pro�t organization typically carries out, especially in developing countries, changes along its expansion path. the �rst activities usually con- centrate on some form of emergency: saving individuals from imminent physical danger or starvation, helping to avoid some irreversible health problem, etc. in this sense, the mar- ginal returns are extremely high at the beginning. unfortunately, there is no shortage of such problems to solve, and very often, the observation of similar severe problems is exactly what motivates numerous motivated individuals to establish a non-governmental organiza- tion that targets it. however, the next activities of the non-pro�t�s project involve tasks which are less emergency-driven and more oriented towards making the livelihoods of ben- e�ciaries sustainable (e.g. putting children to school, providing economic activities so that bene�ciaries can earn their living). this is typically the stage of "teaching how to �sh rather than providing �sh". smillie ( ) argues that this second type of tasks is much harder to accomplish successfully and involves a much longer period of time before results can be ob- served. such long-run perspective also implies that many organizations prefer to concentrate on the emergencies; however, the resulting competition among them for "saving lives" limits their expansion, as has been underlined by observers of large-scale humanitarian emergencies such as the tsunami (mattei ). in our case, this implies that, for a given non-pro�t organization, graphically, the slope of g is fairly steep at low levels of funding (the emergency activities), and becomes �atter beyond certain level (sustainable development activities). . informational asymmetries in the non-pro�t sector we have assumed (except in the extension with conditional warm-glow giving) that motives for giving are disconnected from the performance of the non-pro�t sector. this assumption also implies that non-pro�ts are unable to signal their (motivational) type to donors. in theory, such signalling would be possible by allowing non-pro�t managers to "burn money" (in such case, in a separating equilibrium, the altruistic types would engage in burning money whereas sel�sh types would not). however, in practice it is di¢cult to imagine an easy way of doing so. one possibility is to allow for self-imposed restrictions on overheads; but, to be credible, such a scheme would require a third-party certi�cation of such restrictions (e.g. by the government). assuming away such credibility problems, the possibility of self-imposed restrictions would not destroy our main mechanism, but is likely to reduce the range in which multiple equilibria occur. another form of signalling is possible if conditionally warm-glow donors di¤er in size (e.g. a few largeandmanysmalldonors), and largedonors canobtain (even imperfect) information about the non-pro�t managers� types at a reasonable cost. again, this would reduce the range of parameters in which the bad equilibrium exists (both in the unique-equilibrium and the multiple-equilibria cases). . lack of contractibility of non-pro�t output third, we have assumed severe contractual problems on non-pro�ts� output; in particular, we have imposed that it is completely unobservable or unveri�able. the existence of these contractual problems has a double implication for the model: motivation serves as a substi- tute for contracts; however, it is exactly this non-contractibility that attracts low-motivation individuals into the non-pro�t sector. clearly, making the non-pro�ts� output measurable would ease the problem of adverse selection. however, in the sectors where output is well measurable, the role of non-pro�ts is less important (at the extreme, if the output is perfectly measurable, the production can be fully taken care of by for-pro�t �rms), as has been argued by glaeser and shleifer ( ). thus, the strong assumption that we impose is justi�ed by the scope of the applications of our analysis. . absence of non-pecuniary incentives finally, we have assumed away other (not strictly pecuniary) forms of incentives, that have been studied in the organizational economic literature (see, for instance, besley and ghatak and bradler et al. ). it is possible that such incentives are asymmetrically valued the models by vesterlund ( ) and andreoni ( ), where obtaining a large leadership donation serves as a credible signal of quality, can serve as a microfoundation for this type of analysis. by motivated and unmotivated types. if, for instance, the prestige associated with working in the non-pro�t sector, independent from the level of output, is valued relatively more by motivated types, this shifts the uh curve upwards and thus increases the range of parameters with honest equilibrium. on the contrary, if prestige is valued more by unmotivated types (e.g. because of the indirect pecuniary bene�ts that such prestige can deliver), the range of honest-equilibrium parameters would shrink. conclusion in this paper, we have built a theory of private provision of public goods via voluntary contributions to organizations in the non-pro�t sector, in a general-equilibrium occupational- choice framework. the main applications of this theory lie in two domains. the �rst is foreign aid intermediation by ngos. aid is being increasingly channelled via ngos, essentially driven by increasing emphasis of project ownership, decentralization, and participatory development. this emphasis is mostly driven by the disillusionment in government-to-government project aid, which is often considered to be politicized and/or easily corruptible (see, for instance, empirical evidence by alesina and dollar and kuziemko and werker ). however, little analysis so far has been made concerning the implication of massive channelling of aid via ngos (with the exception of the few papers mentioned earlier and the recent review study by mansuri and rao, ). the application of our theory to foreign aid allows to explore these implications, in particular, the two e¤ects of aid in�ows on the functioning of the ngo sector: dilution (increase in n) and selection (unmotivated agents� entry into the ngo sector). the key implication of our results is that as the ngo channel of aid expands, the investment into better accountability in the ngo sector (e.g. restrictions on diversion of funds for private perks) is fundamental, so as to prevent the appearance of the dishonest equilibrium. optimal aid delivery through ngos requires harder controls accompanying the scaling-up of aid e¤orts. the second application, instead, pertains to the recent debates on the accountability, value-for-money, and performance-based pay in the non-pro�t sector in developed countries. existing literature recognizes that �rms in the non-pro�t sector, because of the inherent di¢culty of measuring their performance, are prone to asymmetric information and agency problems. understanding the conditions under which these problems are most salient is an open issue in public economics literature. our analysis contributes to this debate by indicating that the role of (endogenously determined) relative outside options of unmotivated and motivated individuals inside the non-pro�t sector is crucial. in particular, what matters is the type of individuals (i.e. motivated or unmotivated ones) that exit more intensively the non-pro�t sector, when incomes in the private sector (and thus donations to the non-pro�t sector) decrease. if, as in our model, unmotivated agents exit more intensively, the recession can have a cleansing e¤ect, in terms of motivational composition of the non-pro�t sector. this is, in our view, an interesting hypothesis that can be tested empirically in future work. two further promising avenues for future research are worth mentioning. the �rst is the role of speci�c public policy instruments towards the non-pro�t sector. several recent studies on the economic of charities and non-pro�ts have explored the e¤ectiveness of direct versus matching grants (andreoni and payne , ; karlan et al. ). our analysis in section indicates that matching grants might have an additional e¤ect that operates through motivational composition of the non-pro�t sector: such �nancing induces non-pro�ts to engage more actively in fundraising (and thus to reduce their internal resources devoted to working on their projects), and this might induce the motivated individuals to quit the non- pro�t sector. a more complete analysis of the e¤ectiveness of matching grants as compared to direct ones, that takes into account these various e¤ects, looks very promising. the second possibility relates to the key speci�city of the non-pro�t/ngo sector: the disconnection between who �nances and who bene�ts from the activity of this sector. the resulting monitoring problems create the need in coordinating scaling up of �nancing with investment into better monitoring of the sector. as suggested by ruben ( ), evaluation of aid e¤ectiveness can generate social bene�ts even when one can learn relatively little from the evaluation exercise, because the very fact of being evaluated makes rent extraction more di¢cult and therefore might improve the motivational composition on non-pro�t/ngo sector. the framework developed in this paper might allow to build an analysis of these indirect e¤ects of evaluation of development projects. appendix a: omitted proofs proof of proposition . part (i). first of all, notice that by replacing n = n into ( ), it follows that a( + �) �� > implies u�l(n ) > : hence, since u � l( bn) = , it must necessarily be the case that n < bn. because of lemma , this also means that u�l(n ) > u � h(n ): now, since u � l(n ) = y(n ), then y(n) < u � l(n ) for any n < n , meaning that whenever n < n the mass of non-pro�t managers must at least be equal to : (the total mass of ml-types). but this contradicts the fact that n < : ; hence an equilibrium with n < n cannot exist. moreover, an equilibrium with n > n cannot exist either, because whenever n > n holds, y(n) > u � h(n) and y(n) > u � l(n), contradicting the fact that there is a mass of individuals equal to n > choosing to become non-pro�t managers. as a result, when a( + �) �� > , an allocation with n� = n�l = n represents the unique equilibrium. since u�h(n ) < u � l(n ) = y(n ), in the equilibrium, all mh-type become private entrepreneurs, and a mass : � n of ml-type agents (who are indi¤erent between the two occupations) also become private entrepreneurs. part (ii). since a( + �) �� < implies u�l(n ) < , when the former inequality holds, n > bn. moreover, notice that an equilibrium with n � n cannot be exist, as it would contradict the fact that n < : . in turn, because the equilibrium must necessarily verify n > n > bn, only motivated agents will become non-pro�t managers, while all unmotivated agents will self-select into the for-pro�t sector. now, by the de�nition of n in ( ), it follows that if n � : , then n� = n�h = n represents the unique equilibrium allocation. (notice that a( + �) �� < ensures n > n :) in that situation, the mh-types are indi¤erent across occupations (and there is a mass : �n of them in the private sector), while when n < n all motivated agents wish to become non-pro�t managers contradicting n < : , andwhenn > n nobodywouldactually choose the non-pro�t sector contradicting n > . with a similar reasoning, it is straightforward to prove that when n > : , the unique equilibrium allocation is given by n� = n�h = : , as in that case the condition u�l � � < y � � < u�h � � holds, whereas for n < : all mh-types intend to become non- pro�t managers, and when n > : there is either nobody or only a mass one-half of agents who wish to go the non-pro�t sector. proof of proposition . part (i). (a) first of all, recalling ( ), notice ��a > implies n < . using the results in proposition , it then follows that when a( + �) �� < < ��a and � = , in equilibrium, n� = n�h = n , where recall that n is implicitly de�ned by ( ). let now nh be implicitly de�ned by the following condition: n� h [�a( �nh) � +�] ( �nh) �� a; ( ) in raw words, nh denotes the level of n that equalizes ( ) and the utility obtained by a motivated non-pro�t manager when d=n is given by ( ). from ( ), it is easy to observe that when � = , nh = n . in addition, di¤erentiating ( ) with respect to nh and �, we obtain that @nh=@� > . let now � � �a ��( + �); ( ) and, using ( ), notice that [�a( �n)� +� ]=n = ; hence nh(� ) = n. as a con- sequence of all this, when a( + �) �� < < ��a, for all � � < � , in equilibrium, n� = n�h = nh(�), where @nh=@� > , and nh (�) : [ ;� ) ! [n ;n). (b) using again the fact that [�a( �n)� +� ]=n = , from ( ) it follows that, for all � > � , the utility achieved as non-pro�t managers by ml-types must be strictly larger than that obtained by mh-types. let now �a � ��a h� ��a � � � � i : ( ) using ( ) and ( ), notice that when n = and � = �a, the utility obtained by motivated non-pro�t managers is equal to y � � . all this implies that, when a( + �) �� < < ��a, for all � � � < �a, in equilibrium, n� = n�l = nl(�) � , where nl(�) is non- decreasing in�: inparticular, forall� � � � ��a( � �) the functionnl(�) is implicitly de�ned by � �a( �nl)� +� nl � ( �nl) �� a; ( ) while for all ��a( � �) < � < �a, nl(�) = . lastly, when � = ��a( � �), the expression in ( ) implies nl = , proving that nl(�) : (� ;�a] ! � n; � is continuous and weakly increasing. (c) first, note that when � > �a, the expression in ( ) delivers a value of nh > . as a result, motivated agents must necessarily be indi¤erent in equilibrium between the two occupations, since some of them must choose to actually work as non-pro�t managers to allow nh > . in addition, since by de�nition of �a in ( ), �a [( �n) � +�a]=n > y(n) when n = , all unmotivated agents must be choosing the non-pro�t sector when � > �a. let thus nlh be implicitly de�ned by the following condition: n� lh [�a( �nlh) � +�] ( �nlh) �� a: ( ) di¤erentiating ( ) with respect to nlh and �, we can observe that @nlh=@� > . from ( ), we can also observe that lim�!�a nlh = and lim�! nlh = . as a result, we may write nlh(�) : (�a; ) ! � ; � , with @nlh=@� > . moreover, since n�l = ; � > �a, it must be the case that in equilibrium n�h = nlh(�)� . part (ii). (a) because of proposition , when � = , in equilibrium, n�h � and n�l = : next, let �b � ��a( � �), and note that: � �a � �� +�b � = ��a; ( ) and note that the right-hand side of ( ) equals y( ), while its left-hand side equals d=n when n = and � = �b. furthermore, notice that [�a � �� + �] is strictly increasing in �: as a consequence, it follows that in equilibrium, n�l = for any � � � �b. in addition, denoting bynh (�) = minf ;�g, where � is the solutionof [�a( ��) � +�]=� = a=( ��) ��, the result, n�h = nh (�) for any � � � �b obtains. (b) this part of the proof follows from the de�nition of � in ( ), together with the fact that [�a � �� +�] > ��a, for all � > �b. as a result, we may implicitly de�ne the function nhl(�) by � �a( �nhl)� +� nhl � ( �nhl) �� a; and observe that @nhl=@� > . noting that, whenever n = nhl(�), ml-types are indi¤erent across occupations completes the proof of this part. (c) this part of the proof follows again from the de�nition of � in ( ), which implies that for all � > � , the expression in ( ) yields d=n > when n = n. for this reason, whenever � > � , the mh-types must be indi¤erent across occupations in equilibrium, while all ml-types will strictly prefer the non-pro�t sector. we can then implicitly de�ne the function nlh(�) by n � lh [�a( �nlh) � +�] � ( �nlh) �� a; and observe that @nlh=@� > to complete the proof. proof of proposition . part (i). first, recall that in an honest equilibrium e = . second, using ( ) and ( ) when n = n�h, we have that �a( �n�h) � n�h = a ( �n�h) �� , n�h = � + � < : therefore, an honest equilibrium must necessarily feature n�h = �=( + �), with mh types indi¤erent across the two occupations. in such an equilibrium, they obtain a level of utility equal to a( +�) ��. third, from ( ) it follows that this solution is a nash equilibrium, as the best response by ml-type non-pro�t managers would be el = when a( +�) �� < , while el = otherwise. in both cases, a( + �) �� implies that unmotivated agents should prefer the private sector to the non-pro�t sector. moreover, this must be the unique nash equilibrium solution, since the incentives for an ml-type agent to start a non-pro�t will decline with the average level of e, which in equilibrium will never be below : as implied by ( ). part (ii). preliminarily, let �rst de�ne en � �=( +�). note then that, when e = ; the payo¤ functions ( ) and ( ) are equalized when n = en; namely, u�h( en) = v �( en). next, notice that, for a given e, both ( ) and ( ) are strictly decreasing in n, while they grow to in�nity as n goes to zero. hence, to prove that a dishonest equilibrium exists, it su¢ces to show that the condition a � [ =( + �)] �� implies u�h( en) � u�l( en). to prove that the dishonest equilibrium is the unique equilibrium, notice �rst that an honest equilibrium is incompatible with a � [ =( + �)] ��. therefore, the only other alternative would be a mixed-type equilibrium with all agents indi¤erent between the private and non-pro�t sector. yet, for ( ) and ( ) to be equal, it must be that d=n = e. this equality in turn implies that all activities must yield a payo¤ equal to , however, when a � [ =( + �)] ��, this would be inconsistent with e < , therefore a mixed-type equilibrium cannot exist either. part (iii). first of all, following the argument in the proof of part (i) of the proposition, notice that an honest equilibrium cannot exist, since when a( + �) �� > unmotivated agents would like to deviate to the non-pro�t sector and set el = . secondly, notice that a necessary condition for a dishonest equilibrium to exist is that u�h > when n = en and e = , but replacing n = en and e = into ( ) yields a value strictly smaller than when a < [ =( + �)] �� . asaresult, whena( +�) �� < a < [ =( + �)] �� theequilibriummust necessarily be of mixed-type, with all agents indi¤erent across occupations. this requires that u�h(n �) = u�l(n �) = v �p(n �) = . >from ( ) we obtain that v �p(n �) = implies n�mixed = � a �� : in addition, u�h(n �) = u�l(n �) requires that emixed = d=n, which using n�mixed = �a �� leads to ( ). therefore, using the facts that e�h = : and e � l = , the levels of n�h and n � l in ( ) immediately obtain. lastly, to prove that this equilibrium is unique, notice that e�mixed in ( ) lies between : and , thus there must exist only one speci�c combination of n�h and n � l consistent with a mixed-type equilibrium. proof of proposition . first of all, notice that nh = : cannot hold in equilibrium, as ( ) implies that in that case d=n = , an no agent would then choose the non-pro�t sector. we can then focus on three equilibrium cases: (i) n�l = and < n � h < : , with ml-types strictly preferring the private sector (ii) n � l � : and n�h = , with mh-types strictly preferring the private sector (iii) � n�l � : and � n�h < : , will all types indi¤erent across occupations. case (i). for this case to hold in equilibrium, the following condition must be veri�ed: �ha � �nh � ( �nh) �� nh| {z } u� l (nh; ) < a ( �nh) ��| {z } y(nh; ) = " �ha � �nh � ( �nh) �� nh # | {z } u� h (nh; ) : ( ) for u�l(nh; ) < y(nh; ) in ( ) to hold, nh > �h=( + �h) must be true. next, since u�l(nh; ) < u � h(nh; ) , u�l(nh; ) < , and y(nh; ) is strictly increasing in nh while u�h(nh; ) is strictly decreasing in it and u � h( ; ) = , a su¢cient condition for ( ) to hold in equilibrium is that �ha � �nh � ( �nh) �� nh < when nh = �h + �h ; which in turn leads to the condition a < [( + �h)=( + �h)] �� . case (ii). the case takes place when the following condition holds: � �ha ( �nl) �� nl � | {z } u� h ( ;nl) < a ( �nl) ��| {z } y( ;nl) � �ha ( �nl) �� nl| {z } u� l ( ;nl) : ( ) using the expressions in ( ), notice that for u�l( ;nl) > y( ;nl) to hold, nl < �h= . but, since < �h � , nl < �h= and u�l( ;nl) > y( ;nl) cannot possibly hold together. as a consequence, in equilibrium, u�l( ;nl) = y( ;nl) must necessarily prevail, implying in turn that nl = �h= . next, since u � l(nh; ) > u � h(nh; ) , u�l(nh; ) > , a su¢cient condition for ( ) to hold in equilibrium is that �ha ( �nl) �� nl > when nl = �h ; which in turn leads to the condition a > ( � �h= ) ��. case (iii). keeping in mind that u�l(nh; ) = u � h(nh; ) , u�l(nh; ) = , this case will arise when the following equalities hold: a ( �nh �nl) ��| {z } y(nh;nl) = �ha � �nh � ( �nh �nl) �� (nl +nh)| {z } = u� l (nh;nl) : ( ) recallingthede�nitionofn in ( ), u�l(nh;nl) = leads to [�h ( : �nh)]= � �a =( ��) � = , from where we obtain: nh = � �a �� h : ( ) next, using again the de�nition of n in ( ), we may obtain nl = � �a =( ��) � � nh, which using ( ) yields: nl = � �a �� + �h �h � : ( ) lastly, ( ) implies that nh > , a > ( � �h= ) �� ; while ( ) means that nl > , a < [( + �h)=( + �h)] �� , completing the proof. proof of proposition . first of all, from ( ), it is straightforward to observe that neither nh = : , nor = nh < nl can possibly hold in equilibrium, as both situations would imply d=n = , an no agent would thus choose the non-pro�t sector. second, set nl = into ( ), and take the limit of the resulting expression as nh approaches zero, to obtain lim nh! d n �� nl= = �h a nh (nh) = : the above result in turn implies that = nh = nl cannot hold in equilibrium either, as in that case the non-pro�t would become in�nitely appealing to mh-types. third, suppose < nh < nl = . using ( ) and ( ), for this to be an equilibrium, it must necessarily be the case that �h a � �nh � nh � �nh � �� +nh � � a � �nh � �� : ( ) however, the condition ( ) cannot possibly hold, since it would require �h ( : �nh)nh � ( : +nh) , which can never be true. because of the previous three results, the only possible equilibrium combinations are: (i) n�l = and < n � h < : , (ii) � n�l � : and < n�h < : , will all types indi¤erent across occupations. case (i). for this case to hold in equilibrium, condition ( ) must be veri�ed, which following the same reasoning as before in the proof of proposition leads to the condition a < [( + �h)=( + �h)] �� . case (ii). for this case to hold in equilibrium, the following equalities must all simulta- neously hold: d n = �h a � �nh � nh ( �nh �nl) �� (nh +nl) = y(n) = a ( �nh �nl) �� = : ( ) taking into account the de�nition of n in ( ), it follows that y(n) = requires nh +nl = �a �� . as a result, ( ) boils down to the following condition: �h � �nh � nh � � �a �� = ( ) the expression in ( ) yields real-valued roots if and only if a � � � p �h= � �� : ( ) when ( ) is satis�ed, the solution of ( ) is given by: nh = >>>>< >>>>: r � � s � � �a =( ��) � �h ; r � + s � � �a =( ��) � �h : ( ) note now that the roots r and r are not necessarily equilibrium solutions for nh. more precisely, since nl = [ �a �� ]�nh, then nl � , nh � [ �a �� ]. as a consequence, for nh = r in ( ) to actually be an equilibrium solution, it must then be the case that r � �a �� . but this inequality is true only in the speci�c case when a = � � p �h= � �� and p �h = , which in turn also implies that r = r in ( ). without any loss of generality, we may thus fully disregard r , and check under which conditions r � �a �� . using ( ), and letting x � �a �� , an equilibrium with nl � when nh = r requires the following condition to hold: (x) � � s � x �h � x; ( ) now, notice (x) = x when a = [( + �h)=( + �h)] �� . in addition, noting that (x) > and (x) > , it then follows that: i) (x) < x, for all a > [( + �h)=( + �h)] �� ; while (x) > x, for all ( � p �h= ) �� < a < [( + �h)=( + �h)] �� . consequently, when a � [( + �h)=( + �h)] ��, there is anequilibriumwithnh = r andnl = [ �a �� ]�r . lastly, to prove that @f=@a < , note that f = (x)=x, hence @f @a = x @x @a � x � � x �h � � @x @a ; from where @f=@a < stems from noting that @x=@a < and that � x � � x �h � � > ; because of ( ). derivation of equilibrium regions in figure . i) honest equilibrium region: this type of equilibrium arises when �i < < v � p for any � n � , where v � p is given by ( ) and �i by ( ). for �i < v � p to hold for any � n � it su¢ces to pin down when it holds for n = , which in turn leads to t < t � ( � �)=( � �) : ( ) next, for �i < v � p we need that n < � ( � t)+ t + � ( � t): ( ) therefore, plugging the rhs of ( ) into ( ), leads to the condition that �i < whenever a < ( � t)� [ + � ( � t)] �� : ( ) as a result, the region bounded by ( ) and ( ) features an �honest equilibrium�. ii) dishonest equilibrium region: this type of equilibrium needs, �rst, that condition ( ) fails to hold. second, it also needs that (�i) < v �p holds, so that mh-types choose the private sector. for (�i) < v �p to obtain, it must be that a > [t+ � ( � t)] � �� ( � t) � : ( ) notice now that the rhs of ( ) is equal to the rhs of ( ) when t = t; while the former lies above (below) the latter when t < t (when t > t). as a consequence, the region exhibiting a �dishonest equilibrium� is given by a > ( � t)�� [ + � ( � t)]�� whenever t � t and by ( ) whenever t > t. iii) mixed-type equilibrium region with f > : from the previous results it follows that when ( ) holds and t > t, we must necessarily have an equilibrium in which all mh-types choose the non-pro�t sector, while ml-types lie indi¤erent between the two sectors, and a fraction of them choose the non-pro�t sector as well. iv) mixed-type equilibrium region with f < : from the previous results it also follows that when both ( ) and ( ) fail to hold and t > t, we must necessarily have an equilibrium in which ml-types choose the non-pro�t sector, while mh-types lie indi¤erent between the two sectors, and a fraction of them choose the non-pro�t sector as well. references [ ] aldashev, g., and verdier, t. 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[ ] union of international associations ( ). the yearbook of international organiza- tions. brussels: uia. �� ! ��"�� # �$��"�� #� �$��"��%� ��&"�� ' ��%� �� '� ��%�� (��&��"�� ) �*�� microsoft word - di dio - impaginato inglese psicoart n. .doc psicoart n. – cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty: brain response to classical and renaissance sculptures* i n t r o d u c t i o n one of the most debated issues in aesthetics is whether beauty may be defined by some objective parameters or whether it merely depends on subjective factors. the first perspective goes back to plato's objectivist view of aes- thetic perception, in which beauty is regarded as a prop- erty of an object that produces a pleasurable experience in any suitable viewer. this stance may be rephrased in bio- logical terms by stating that human beings are endowed with species-specific mechanisms that resonate in re- sponse to certain parameters present in works of art. the alternative stance is that the viewers' evaluation of art is fully subjective. it is determined by experience and per- sonal values. although it is commonly accepted that subjective criteria play a major role in one's aesthetic experience, it is also reasonable to accept that there exist specific biologically- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - based principles which may facilitate the perception of beauty in the beholder. after all, new artists typically first master the ability to represent standard principles of beauty, such as symmetry and proportion, and only then eventually bend these rules to represent their overall vi- sion of the world. in the present study we investigated the aesthetic effect of objective parameters in the works of art by studying brain activations (fmri) in viewers naïve to art criticism who observed images of sculptures selected from masterpieces of classical and renaissance art that are commonly ac- cepted as normative western representations of beauty. an important feature that characterized the present study distinguishing it from others that also have attempted to clarify the neural correlates of aesthetic perception was the use of two sets of stimuli that were identical in every aspects but one: proportion. more specifically, a parame- ter that is considered to represent the ideal beauty, namely the golden ratio ( : . ), was modified to create a degraded aesthetic value of the same stimuli in a con- trolled fashion (figure ). stimulus manipulation was very contained and in no cases were the modified sculp- tures judged as deformed representations of the human body, as assessed in post-scanning debriefing. another important feature of the present study was that the same stimuli were presented in experimental conditions that varied in the instructions given to the participants. in one condition-observation (o) – viewers were asked to ob- serve the sculptures as if they were in a museum, without any explicit request to judge them. by inducing a “simply enjoy” contextual frame and without having the volun- teers perform any specific cognitive task, we meant to elicit a most spontaneous/unbiased brain response to the artworks. in a second-aesthetic judgment (aj)- and third -proportion judgment (pj)- condition, on the other hand, the viewers had to judge the stimuli on the basis of their cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - aesthetic or proportion quality, respectively. therefore, in both these conditions the participants were involved in an additional cognitive evaluation of the stimuli. whereas the aesthetic judgment condition allowed us to determine brain activations in response to the volunteer's subjective evaluation of the stimuli, the pj condition was used to ob- serve brain response during a task of overt proportion evaluation. in order to assess both “objective” and “subjective” aes- thetic values, two types of analysis were carried out. in the first one, aimed at establishing the neural responses to objective beauty parameters, we contrasted brain acti- vations during the presentation of the canonical sculp- tures vs. their modified counterparts. the underlying ra- tionale was that the canonical proportions intrinsic to the original works of art would elicit enhanced activity in ar- eas mediating pleasure and, in particular, in the insula, the cortical region known to be involved in the feeling of emotion. we also expected signal increase to be particu- larly strong during the observation condition, where brain response to the artworks was not interfered with by addi- tional cognitive requests (i.e. aesthetic or proportion judgment). the second type of analysis, on the other hand, was aimed at the evaluation of brain responses re- lated to the overt subjective appreciation of the stimuli by contrasting the brain activations obtained during the presentation of the judged-as-beautiful against the judged-as-ugly images. in this analysis, we expected the judged-as-beautiful images to produce a stronger activa- tion, than the judged-as-ugly images, in areas involved in the subjective emotional appraisal of the stimuli. in this case, however, we did not bring forward any specific pre- diction due to the divergent existing evidence in the field. cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - figure . example of canonical and modified stimuli. the original image (doryphoros by polykleitos) is shown at the centre of the figure. this sculpture obeys to canonical propor- tion (golden ratio = : . ). two modified versions of the same sculpture are presented on its left and right sides. the left image was modified by creating a short legs: long trunk rela- tion (ratio = : . ); the right image by creating the opposite relation pattern (ratio = : . ). all images were used in be- havioural testing. the central image (judged-as-beautiful on %) and left one (judged-as-ugly on %) were employed in the fmri study. . m a t e r i a l s a n d m e t h o d s . participants fourteen healthy right-handed volunteers ( males, fe- males; mean age . , range years) participated in this study. they were educated undergraduate or graduate students, with no experience in art theory. after receiving an explanation of the experimental procedure, partici- pants gave their written informed consent. the study was approved by the independent ethics committee of the santa lucia foundation (scientific institute for research hospitalization and health care). . stimuli fifteen -dimentional images of classical and renais- sance sculptures were chosen following a specific selec- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - tion method. all the original pictures met the criteria of canonical proportions defined by the ratio : . be- tween body parts; among the modified image-versions, presented a “long-trunk, short-legs” modification (range = : . - : . ), whereas the remaining images pre- sented the opposite pattern of modification (range = : . - : . ). twenty sculptures represented male bodies and female bodies. . paradigm the stimuli were presented in three experimental condi- tions: observation (o), aesthetic judgment (aj), and pro- portion judgment (pj). each participant underwent separate fmri runs, repeating each condition twice. the condition order was maintained fixed across all partici- pants, with observation condition first, explicit aesthetic judgment second, and explicit proportion judgment, last. by keeping the observation runs first, we aimed at meas- uring unbiased (spontaneous) brain responses to the type of the stimuli (canonical and modified). to make sure that volunteers were not biased in their aesthetic judg- ment by explicit proportion evaluation, the aesthetic judgment condition always preceded the proportion judgment runs. within each run we presented stimuli ( canonical and modified) in a randomized order, but never repeat- ing the same image within a run. a question mark in- structed the participants to respond to the images after a s-fix interval following each stimulus presentation by using a response box placed inside the scanner. . task participants lay in the scanner in a dimly lit environment. the stimuli were presented on a black background and cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - were displayed on a screen visible through a mirror mounted on the interior of the head coil. at the beginning of each session, a s visual instruction informed the vol- unteers about the upcoming condition/task. on each trial, a ms central fixation point plus ms blank-screen interval preceded the presentation of the sculpture stimu- lus. the stimulus then appeared at the centre of the screen for s and it was followed by another s blank- screen interval. after this, a question mark instructed the observer to respond to the stimulus (see below). the question mark remained on screen for ms and was followed by a jittered interval ranging – s, with a uni- form distribution. during observation condition (o), the volunteers were required to observe the images as if they were in a mu- seum and, when the question mark appeared, they had to indicate whether they paid attention to the picture or not. during the aesthetic and proportion judgment conditions, the volunteers were required to decide whether they liked the image (aj) or whether they found it proportional (pj), respectively. thus, all conditions required a re- sponse from the participants. using the index or middle finger of the right hand, the participants answered yes or no, according to the instruction presented at the start of each run. specifically, before the observation sessions, the participants were instructed to answer “yes” if they paid attention to the stimulus just presented, whereas to press “no” to indicate that they did not pay attention to the stimulus. the question “did you pay attention to the image?” was introduced to make sure that participants were actually looking at the stimuli during fmri scanning. during aj condition, participants were required to indicate “yes” if they aesthetically liked the image and “no” if they did not. finally, pj condition required the observers to explicitly indicate whether they thought that the image was propor- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - tional by pressing “yes” or if they thought that the image was disproportionate by pressing “no”. the volunteers underwent six subsequent scanning runs, each lasting approximately . min. each fmri runs con- sisted of trials with each sculpture images presented once. . image acquisition functional images were acquired with a magnetom vision mri scanner (siemens, erlangen, germany) operating at t. blood oxygenation level dependent (bold) contrast was obtained using echo-planar t * weighted imaging (epi). the acquisition of transverse slices with an ef- fective repetition time of . s, provided coverage of the whole cerebral cortex. the in-plane resolution was × mm. . data analysis two types of analyses of fmri data were performed. a stimulus-based analysis (“objective beauty”) considered only the type of image that was presented to the partici- pants: i.e. with canonical (c) or modified (m) propor- tions. the second analysis (“subjective beauty”) catego- rized each sculpture image according to the behavioural responses measured during aj runs. for this analysis, we included only images that were consistently judged either beautiful (b) or ugly (u) in both runs requiring aesthetic judgment. event-related fmri data were processed with spm . the first four image volumes of each run were discarded to allow for stabilization of longitudinal magnetization. for each participant, the remaining volumes were re- aligned with the first volume, and the acquisition timing was corrected using the middle slice as reference. to al- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - low inter-subject analysis, images were normalised to the montreal neurological institute (mni) standard space, using the mean of the functional images. all images were smoothed using an isotropic gaussian kernel (full width at half maximum = mm). statistical inference was based on a random effects ap- proach. this comprised two steps. first, for each sub- ject, the data were best-fitted (least-square fit) at every voxel using a linear combination of the effects of interest. the effects of interest were the timing of the fixation point onsets, the presentation times of the sculptures (c & m; or b & u), and the presentation times of the question mark that cued overt responses. all event-types were con- volved with the spm standard haemodynamic response function (hrf). linear compounds (contrasts) were used to determine common effect (c+m vs. rest) and differen- tial effects associated with the presentation of the sculp- tures (c-m and m-c; or b-u and u-b), separately for each of the three conditions (o, aj and pj). for each subject, this led to the creation of six contrast-images, that is three contrasts c+m vs. rest–one for each condition, and three contrasts c-m vs. rest, again one for each condition. ad- ditionally, three contrast-images were also created, which contrasted judged-as-beautiful vs. judged-as-ugly images for each condition. these contrast-images then underwent the second step that comprised three separate anovas. one considering overall pattern of activation c+m vs. rest modeled for each condition; one considering “objective beauty” (c vs. m) modeled for each condition; and one considering “subjective beauty” (b vs. u) for each condition. finally, for each of the three separate anovas, linear compounds were used to compare these effects, now using between- subjects variance. correction for non-sphericity was used to account for possible differences in error variance across conditions and any non-independent error terms cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - for the repeated measures. the following contrasts were tested. first, within the “common effects”, anova (c+m vs. rest) averaging across all experimental conditions (o, aj, pj). for this, the spm-maps were thresholded at p-corrected = . (voxel-level). the other two anovas assessed any stimu- lus -specific effect (“objective”: c-m, m-c; or “subjective”: b-u, u-b). we tested for main effects of stimulus across the three experimental conditions (o, aj, pj); and for in- teractions between stimulus and condition. additional contrasts explored simple effects separately for the differ- ent conditions (e.g. b-u, during aj only). for all these stimulus-specific effects, we used p-corrected = . at the cluster-level (cluster size estimated with a voxel-level threshold of p-uncorrected = . , extent threshold = voxels). in addition, because of our prior hypothesis concerning the possible involvement of the insula in aesthetic appre- ciation, we used a small volume correction procedure to test for the effect of “objective beauty” (c-m; within and across o/aj/pj conditions) specifically in this region. the search volume was derived from mario livio center- ing a sphere at mni x, y, z = , , ; with a radius of mm. . r e s u l t s a n d d i s c u s s i o n . fmri behavioural data the viewers' evaluation of the stimuli, as expressed in the aesthetic judgment condition, showed that the canonical images were mostly evaluated positively ( %, sd = . ), whereas the modified images were generally scored with a negative rating ( %, sd = . ). this finding was in ac- cord with a preliminary behavioural testing used for im- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - ages selection that also showed the relevance of propor- tion in aesthetic evaluation. in this test violation of ca- nonical proportions accounted for % of the variance in aesthetic rating (partial eta ). . overall effect of viewing the sculptures mri analysis was carried out by first assessing the overall effect of viewing the sculptures contrasting canonical (c) and modified (m) images (pooled together, c+m) with rest, across all three conditions (o, aj, pj; p- corrected< . ). as shown in figure , activations were found in occipital and temporal visual areas, including lingual and fusiform gyri. additionally, activations were observed in the infe- rior parietal lobule (ipl) bilaterally, in the sma/pre-sma complex, ventral premotor areas, and in the posterior part of right inferior frontal gyrus (ifg). signal increase was also found in the insula and hippocampus. most of the activations were bilateral, although stronger in the right hemisphere. these results are summarized in table . among the visual activations, besides the primary visual cortex, signal increase was found in the lateral occipital cortex and the inferior temporal lobe (shape sensitive ar- eas), as well as in the mt/mst complex. this last finding, although surprising at first considering that the mt/mst complex is involved in the analysis of motion, is consis- tent with previous data showing that activation of these areas may be elicited by static images that imply motion. most noteworthy was the activation of the inferior parie- tal lobule and especially of the premotor cortex. these ar- eas are known to become active during the observation of actions done by others. it is likely that their activation was dependent on the intrinsic dynamic properties of the sculptures used in this study and the sense of action that cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - they evoked in the observer. figure . brain activation of canonical and modified sculp- tures vs. rest. the analysis was carried out by averaging activity across the three experimental conditions (observation, aesthetic judgment, proportion judgment). group-averaged statisti- cal parametric maps are rendered onto the mni brain tem- plate (p-corrected< . ) . canonical vs. modified sculptures: “objective beauty” the direct contrast of canonical vs. modified images across the three experimental conditions revealed signal increase for the canonical stimuli in the right occipital cortex extending into lingual gyrus; in the precuneus bi- laterally; in the right posterior cingulate gyrus; and in the depth of right inferior frontal sulcus extending to the ad- jacent convexity of the middle frontal gyrus (p- corrected< . ; figure a; see also table a). the lateral occipital cortex (loc) and the temporal vis- ual areas are known to be responsive to the presentation of body parts or even the whole human body. signal in- crease within these areas may be therefore due to a greater representation of canonical body structures rela- tive to the disproportionate ones. the activation of the medial parietal areas and of the prefrontal lobe, on the cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - other hand, might be related to mnemonic functions, possibly elicited by the retrieval of plausible motor con- figurations, better represented by the proportional mate- rial. the central hypothesis underlying the present study was that the contrast of canonical vs. modified stimuli would produce signal enhancement within the insula. accord- ingly, we carried out a small volume correction within the main effects analysis (c-m) using the anatomical coordi- nates reported in a. damasio, t.j. grabowski et alii on the feeling of emotion. the results revealed a significant signal increase in the anterior sector of the right insular cortex extending to the operculum region (maxima x, y, z = , , ; figure b, p< . , corrected for small vol- ume). this effect was particularly strong during observation condition (p< . , corrected for the whole brain volume, table b; p = . , corrected for small volume), which is . figure . brain activation in the contrast canonical vs. modi- fied stimuli. a. main effect of canonical vs. modified sculptures across conditions rendered onto the mni brain tem- plate. b, parasagittal and coronal view showing activations of the right insular region in the main effect. c. activity profile of the right insula. for each con- dition (o, aj, pj) the sig- nal plots show the differ- ence between canonical (c) minus modified (m) sculp- tures in arbitrary units (a.u), +/− % confidence intervals (p-corrected < . ) cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - in the condition in which the volunteers were in a merely observational (museum-like) context (see figure c). sig- nal increase in aj and pj conditions, on the other hand, was virtually the same. the most likely interpretation for this result stands in the different cognitive demands be- tween the first (o) and the last two (aj, pj) conditions. in the latter, in fact, the explicit request of overtly judging the stimuli diverted the volunteers' attention resources towards a specific cognitive demand, thus lessening the natural neural response within the insula. these data are in apparent contrast with some previous findings where symmetry was employed as an objective parameter of aesthetic evaluation. in this study, the au- thors did find significant activation in the anterior insula in the comparison of aesthetic judgment vs. control con- dition as well as in symmetry judgment vs. control condi- tion. however, they considered those areas that were ac- tivated by both aesthetic and symmetry judgment to be not involved in pure aesthetic judgment and hence omit- ted them from the analysis that directly contrasted brain activity for the judged-as-beautiful vs. the judged-as-ugly stimuli. in this way, therefore, they also disregarded the insular activation elicited by objective parameters (i.e. symmetry) intrinsic to the stimuli and involved in mediat- ing the sense of beauty. the question now arises of what possible mechanisms are responsible for the insula activation during the observa- tion of canonical sculptures. the anterior sector of the in- sula has an agranular/disgranular cytoarchitectonic or- ganization and is characterized by extensive connections with limbic structures and with centers involved in auto- nomic functions. functionally, anterior insula is thought to mediate feelings associated with specific emotional states. now, considering the pattern of activity de- scribed in the main effect (c+m vs. rest), there are two concurrent possibilities that may explain insula activa- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - tion. one is that in loc and in the parietal cortex there are neurons specifically sensitive to the canonic body im- ages and that have privileged access to the insula. alter- natively, one may suppose that the canonical sculptures simply determined a stronger activation of cortical neu- rons sending their output to the insula. another possible explanation, based on both main and simple effect analyses (c-m), is that the insula was acti- vated, not by simplest aspects of the visual stimuli (e.g. shape or motion), but rather by higher order information coming from prefrontal areas and . studies in pri- mates showed that area integrates information about object shape with that about actions. while human left area subserves language functions, it is plausible that human right area , selectively activated in the present experiment, could be involved in action/shape integration as well. in this light, canonical stimuli could be more effi- ciently coded in this area and determined, therefore, a stronger activation of the insula relative to the modified one. in this context, also the functional role of prefrontal area could be noteworthy in confronting information from memory (e.g. standard body configuration) with online incoming information (observation of canonical and modified stimuli). to summarize, we propose that the positive emotional feeling elicited in the viewer by the canonical images was determined by a preferential coding of these images, rela- tive to the modified ones, by various cortical areas and by a concurrent, joint activation of the anterior insula. . judged-as-beautiful vs. judged-as-ugly sculptures: “subjective beauty” with this further analysis, we investigated the neuronal substrate associated with subjective appreciation of the sculptures as expressed by each participant in the aj cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - condition ( runs). behavioural data showed that % and % of stimuli were consistently judged, respectively, beautiful (b) and ugly (u) over both aj runs, whereas % was rated inconsistently. only the stimuli that were rated in a consistent way were employed for analysis. the judged-as-beautiful images selectively activated the right amygdala. this effect was observed for the aesthetic judgment condition, as demonstrated by the stimu- lus×condition interaction analysis (maxima: x, y, z = , , − ; p-corrected< . ; figure a,b). the amygdala is a complex nuclear structure. it is inter- connected with several cortical areas and subcortical brain centers and subserves a variety of functional roles. however, a fundamental amygdalar function is to provide neutral stimuli with positive or negative values through association learning. for a long time, studies involving the amygdala have mainly focused on negative stimulus conditioning. how- ever, more recent studies support a role of the amygdala also for positive emotions, both in animals and hu- mans. this property puts the amygdala as a prime can- didate in the storing of implicit emotional memories that can be subsequently accessed and used. in this light, the judged-as-beautiful stimuli could have been judged as such, not on the basis of their objective parameters, but because they were associated with memories charged with positive emotional values. the distinctiveness of each own experience would then partly explain the variance observed in the subjective rating of the observed images. finally, we compared judged-as-ugly versus judged-as- beautiful stimuli. as shown in figure c, the only acti- vated area was a region straddling the central sulcus (somatomotor cortices; p-corrected< . ; see also table a). figure d shows signal change in this region, reveal- ing a particularly strong effect of “ugly” versus “beautiful” images during the explicit aesthetic judgment condition. cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - this selectivity was confirmed by the significant stimulus- by-condition interaction, as reported in table . these data are in accord with previous findings by kawa- bata and zeki showing that a negative evaluation of paint- ings (landscapes, abstract paintings, portraits, still life) determined the activation of the somatomotor region. there is also evidence from other studies that negative emotional stimuli may determine unilateral or bilateral activation in this region. the activation of the somatomotor region during aes- thetic judgment seems rather surprising in the absence of actual movements. however, this activation may find an explanation if one also considers the activity pattern (de- activation) of the orbito-frontal cortex reported in kawa- bata and zeki and also found in our work in a post-hoc analysis. although much attention has been drawn in recent years on the role of the orbito-frontal cortex in re- lation to positive rewards, there is also evidence coming from lesion studies that damage to orbito-frontal cortex causes a liberation of a variety of behaviours, ranging from extreme irritability, hot temper, antisocial behav- iour, to euphoria, locomotor hyperactivity and sexual dis- inhibition. if one admits that a decrease of activity in orbito-frontal cortex mimics, although to a different ex- tent, the effect of a lesion one may account for the motor activation in response to ugly stimuli as a covert release of an appropriate motor behaviour. cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - figure . brain activations in the contrasts “judged-as-beautiful vs. a. parasagittal, coronal and transaxial sections showing activation of the right amygdala in the interaction stimulus (beautiful vs. ugly)×condition (observation; aesthetic judgment; proportion judg- ment). b. activity profile of the right amygdala. for each condition (o = ob- servation, aj = aesthetic judgment, pj = proportion judgment) the signal plots show the difference between beautiful (b) minus ugly (u)-as judged sculptures in arbitrary units (a.u), +/− % confidence intervals. judged-as-ugly” and “judged-as-ugly vs. judged-as-beautiful” stimuli c. statistical parametric maps rendered onto the mni brain template showing activity within left somatomotor cortex in the contrast of ugly vs. beautiful stimuli averaged across the three conditions. d. activity profile (ugly-beautiful) of the left motor cortex. for each condition (o, aj, pj) the signal plots show the difference between ugly (u) minus beautiful (b)-as judged sculptures in arbitrary units (a.u), +/− % confidence intervals (p-corrected< . ). cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - . final considerations the main question we addressed in the present study was whether there is an objective beauty, i.e., if objective pa- rameters intrinsic to works of art are able to elicit a spe- cific neural pattern underlying the sense of beauty in the observer. our results gave a positive answer to this ques- tion. the presence of a specific parameter (the golden ra- tio) in the stimuli we presented determined brain activa- tions different to those where this parameter was vio- lated. the spark that changed the perception of a sculp- ture from “ugly” to beautiful appears to be the joint acti- vation of specific populations of cortical neurons respond- ing to the physical properties of the stimuli and of neu- rons located in the anterior insula. insula mediates emotion feelings. it would be too reduc- tive, however, to think that the sense of beauty occurs be- cause of the activation of this structure alone. insula is also activated by non-artistic stimuli; however, the feeling that these stimuli produce in the observer differs qualita- tively from that determined by artworks. our view is that this specific quality–the sense of beauty-derives from a joint activity of neural cortical populations responsive to specific elementary or high order features present in works of art and neurons located in emotion controlling centers. it has often been claimed that beauty, objectively deter- mined, does not exist because of profound subjective dif- ferences in the evaluation of what is beautiful and what is not. although individual biases are undeniable, it is also rather implausible to maintain that beauty has no biologi- cal substrate and is merely a conventional, experientially determined concept. as gombrich wrote, elements in a picture which determine aesthetical experience are “deeply involved in our biological heritage”, although we are unable to give a conscious explanation to them. cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - the results of our experiment concerning what we called subjective beauty are also relevant here. in the condition in which the viewers were asked to indicate explicitly which sculptures they liked, there was a strong increase in the activity of the amygdala, a structure that responds to incoming information laden with emotional value. thus, instead of allowing their nervous centers to “resonate” in response to the observed stimuli (observation condition), when the viewers judged the stimuli according to their individual idiosyncratic criteria (explicit aesthetic judg- ment), that structure was activated that signals which stimuli had produced pleasant experiences in the past. in conclusion, both objective and subjective factors inter- vene in determining our appreciation of an artwork. the history of art is replete with the constant tension between objective values and subjective judgments. this tension is deepened when artists discover new aesthetic parameters that may appeal for various reasons, be they related to our biological heritage, or simply to fashion or novelty. still, the central question remains: when the fashion and nov- elty expire, could their work ever become a permanent patrimony of humankind without a resonance induced by some biologically inherent parameters? cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - table . brain activity reflecting the common effects of canonical and modified images vs. baseline across conditions (observation; aesthetic judgment; proportion judgment). brain structure sphere maxima x y z z p. corr (vx) occipital lobe inferior occipital gyrus (lo) l - - - inf . r - - inf . middle occipital gyrus l - - - inf . r - inf . r - - inf . parietal lobe supramarginal gyrus r - . . frontal lobe middle frontal gyrus r . . r - . . r . . inferior frontal gyrus r . . r . . r . . r . . r . . brain structure sphere maxima z p. corr (vx) precentral gyrus r . . r . . precentral gyrus l - . . l - . . l - . . supplementary motor area – . . supplementary motor area r . . r . . r . . subcortical/insula ippocampus r - - . . r - - . . ippocampus l - - - . . . . insula r - . . insula l - - . . cerebellum cerebellum - r - - . . cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - table . brain activity reflecting the main effect (a) and the sim- ple effect (b) of canonical vs. modified images brain structure sphere maxima z p. corr x y z cluster level a main effect (c-m) medial parietal lo- be/precuneus r , - , . . l - , - , . posterior cingulum r , - , . inferior occipital gyrus r , - , - . . lingual gyrus r , - , - . cuneus l - , - , . inferior frontal gyrus r , , . . middle frontal gyrus r , , . b simple effect observation (c-m) anterior insula/frontal operculum r , , . . middle frontal gyrus r , , . superior frontal gyrus r , , . table . brain activity reflecting main effect (a) and interaction (b) of judged-as-ugly vs. judged-as-beautiful images brain structure sphere maxima z p. corr x y z cluster level a. main effect precentral gyrus l - , - , . . postcentral gyrus l - , - , . b interaction (stimulus by condition) precentral gyrus l - , - , . . postcentral gyrus l - , - , . inferior parietal lobule l - , - , . l - , - , . cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - a c k n o w l e d g m e n t s we thank g. berlucchi, v. gallese and d. freedberg for comments on the manuscript, g. buccino for providing methodological support, k.d. albano for helping in stimulus modification, s. gazzitano for 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p. rotshtein, r. malach, u. hadar, m. graif, t. hendler, feeling or fea- tures: different sensitivity to emotion in high-order visual cortex and amygdala, “neuron”, n. , november , pp. – ; e.a. phelps, j.e. ledoux, contribution of the amygdala to emotion processing: from animal models to human behaviour, “neuron”, n. , october , pp. - ; j.j. paton, m.a. belova, s.e. morri- son, c.d. salzman, the primates amygdala represents the positive and negative value of visual stimuli during learning, “nature”, n. , february , pp. - . ibid. e.a. phelps, j.e. ledoux, contribution of the amygdala to emo- tion processing, cit. h. kawabata, s. zeki, neural correlates of beauty, cit. about fear, see j.l. armony, r.j. dolan, modulation of spatial at- tention by fear conditioned stimuli: an event-related fmri study, “neuropsychologia”, n. , july , pp. – ; about anger, see: h. zald, the human amygdala and the emotional evaluation of sen- sory stimuli, “brain research. brain research reviews”, n. , janu- ary , pp. - and d.d. dougherty, s.l. rauch, t. deckers- bach, c. marci, r. loh, et al., ventromedial prefrontal cortex and amygdala dysfunction during an anger induction pet study in pa- tients with depression with anger attacks, “archives of general psy- chiatry”, n. , august , pp. – . h. kawabata, s. zeki, neural correlates of beauty, cit. see supporting information text s and figure s in the previous version of this paper published in: . for a review, see e.t. rolls, the orbitofrontal cortex and reward, “cerebral cortex”, n. , january , pp. – and m.l. kringelbach, the human orbitofrontal cortex: linking reward to he- donic experience, “nature reviews neuroscience”, n. , september , pp. - . k k. kleist, bericht über die gehirnpatologie und ihrer bedeutung für neurologie und psychiatrie, “zeitschrift für die gesamte neurolo- gie und psychiatrie”, n. , december , pp. - . for a re- cinzia di dio emiliano macaluso giacomo rizzolatti the golden beauty http://psicoart.cib.unibo.it psicoart n. - view, see f. boller, j.grafman, handbook of neuropsychology, el- sevier, amsterdam . e.h. gombrich, tributes. interpreters of our cultural tradition, phaidon press, oxford . see also v.s. ramachandran, a brief tour of human consciousness, pearson education, new york . untitled directed altruistic living donation: what is wrong with the beauty contest? greg moorlock correspondence to dr greg moorlock, medicine, ethics, society and history, university of birmingham, vincent drive, edgbaston, birmingham b tt, uk; g.j.moorlock@bham.ac.uk received may revised march accepted june published online first june to cite: moorlock g. j med ethics ; : – . abstract this paper explores the specific criticism of directed altruistic living organ donation that it creates a ‘beauty contest’ between potential recipients of organs. the notion of the beauty contest in transplantation was recently used by neidich et al who stated that ‘[a]ltruism should be the guiding motivation for all donations, and when it [is], there is no place for a beauty contest’. i examine this beauty contest objection from two perspectives. first, i argue that, when considered against the behaviour of donors, this objection cannot be consistently raised without also objecting to other common aspects of organ donation. i then explore the beauty contest objection from the perspective of recipients, and argue that if the beauty contest is objectionable, it is because of a tension between recipient behaviour and the altruism that supposedly underpins the donation system. i conclude by briefly questioning the importance of this tension in light of the organ shortage. introduction this paper will explore the specific criticism of direc- ted altruistic living organ donation (dald) that it creates a ‘beauty contest’ between potential recipients of organs. the notion of the beauty contest in trans- plantation was recently used by neidich et al who stated that ‘[a]ltruism should be the guiding motiv- ation for all donations, and when it [is], there is no place for a beauty contest’ (p. ). i will examine this beauty contest objection from the perspective of donors and recipients, and will argue that the poten- tial conflict with altruism does not, as may often be thought, arise from the actions of the donors, but rather from the behaviour of the potential recipients. i will argue that whether this poses a problem for dald rests on the disputed role of altruism in organ donation. background there is a shortage of organs available for trans- plantation in the uk, so patients often have to endure long periods of illness before they eventu- ally receive a transplant, or sometimes they die before being offered a transplant. there are two overarching approaches to increasing the number of donated organs: increasing deceased donations or increasing living donations. increasing the number of deceased donations can be achieved by improving consent rates and effectively using poorer-quality organs. increasing the number of living donors is more difficult because it relies on healthy individuals putting themselves forward for major surgery to benefit others. historically, living donation was only permitted when the donor and recipient were either genetically related or in an appropriate qualifying relationship. this changed in when the first non-directed altruistic living donation (n-dald) was permitted, and a healthy donor gave a kidney to a stranger on the waiting list. n-dald organs are allocated accord- ing to the same impartial criteria used for deceased donation, or used to create paired/pooled transplant chains. although there was some initial resistance to the notion of n-dald, it is now an accepted source of good-quality, if few in number, donations, which have saved additional lives. more recently, dald has been cautiously accepted in the uk. this allows donors to direct their altruistic donations to specific recipients, even though there may be no pre-existing relationship between them. this has occurred in the usa since via dedicated websites such as matchingdo- nors.com, but has only been permitted in the uk since . in the usa, matchingdonors.com charges potential recipients a registration fee, but any kind of commercial transaction, including registration fees, renders dald ineligible in the uk. potential donors join the website (free of charge), look through potential recipients and choose a potential candidate for their organ. as well as registering on dedicated websites, patients can advertise for potential donors via social media such as facebook, twitter or youtube. although there is flexibility in the finer details of how dald might operate, this paper will concentrate primarily on the use of donor/recipient-matching websites such as matchingdonors.com. the adverts many patients’ adverts for donors feature videos, photos and text outlining their medical condition and their (frequently bleak) prognosis without a transplant. this content seems unobjectionable, but many adverts go far beyond this. some videos/ photos include not just the patient, but also their friends and family. these people will provide testi- monials explaining why a donor should choose that specific person to donate an organ to. patients are frequently shown surrounded by their young fam- ilies, with their children explaining how desperately they need their parent to receive a transplant. while this pointedly emphasises the importance of donating organs, it also has a potentially less desir- able effect: organ donation becomes a form of beauty contest where patients with the most heart- rending story are most likely to receive transplants. potential recipients are also keen to demonstrate moral worthiness: many list the charitable activities that they support, emphasise how active they are open access scan to access more free content moorlock g. j med ethics ; : – . doi: . /medethics- - current controversy o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://jm e .b m j.co m / j m e d e th ics: first p u b lish e d a s . /m e d e th ics- - o n ju n e . d o w n lo a d e d fro m http://crossmark.crossref.org/dialog/?doi= . /medethics- - &domain=pdf&date_stamp= - - http://jme.bmj.com/ http://www.instituteofmedicalethics.org/website/ http://jme.bmj.com/ within their community or local church, and highlight that their illness is not their fault. trying to influence people’s donation decisions with information like this represents a significant departure from the usual impartial allocation procedure for altruistically donated organs. policy position dald facilitated by websites has met with resistance in the usa and the uk. the human tissue authority regards dald as legal provided there is no evidence of reward or coer- cion. there is, apparently assumed to be, an increased likelihood of coercion or reward with dald in comparison to living-related donations, so the assessment process for potential donors is par- ticularly rigorous. the british transplant society suggests that non-directed altruistic donation is preferable to dald, as it pre- serves equity of access. they, therefore, suggest that the possi- bility of non-directed donation should be discussed with all potential dald donors. in short, dald appears to be tolerated rather than promoted in the uk, unlike n-dald, which is cele- brated. the dire consequences of the organ shortage mean that one should have good reasons for failing to take full advantage of a particular source of donations. there may be some general con- cerns over promoting living donation when there are still poten- tial gains to be made in deceased donation rates (given that living donation involves subjecting a healthy person to surgery and deceased donation does not), but the current reluctance to embrace and promote dald to lessen the organ shortage appears to be grounded in more specific concerns. the beauty contest criticism the existing literature discussing donor/recipient-matching web- sites suggests that the primary objections are increased risk of reward or coercion, and the beauty contest dynamic, which results in allocation contrary to medical criteria. these objec- tions seem reasonable, but concerns about reward and coercion can be somewhat allayed by the introduction of appropriately rigorous safeguarding and screening. a further ethical criticism is that of the beauty contest. by this, one need not mean that literally the most beautiful candidates are selected, but rather that recipients are selected from a list accord- ing to criteria that make them an attractive choice for donors. many of these criteria are not obviously ‘medical’. for instance, choosing a particular recipient because they created a funny video, or because they have young children who desperately need a parent would clearly deviate from the usual ideas of urgency and medical need. the idea of a beauty contest to determine who lives and who dies certainly seems distasteful,i but distasteful is not always unethical. neidich et al have suggested that the beauty contest dynamic is unacceptable because it is not compatible with altruism. i will now explore this claim from the perspective of donors and recipients, and will argue that if beauty contests in organ donation represent a failure of altruism on the part of donors then this is not unique to dald. i will then explore the issue from the perspective of recipients, and will argue that it is their actions that are at odds with an altruistic donation system. beauty contest and the donors neidich et al suggest that sites such as matchingdonors.com ‘move beyond conventional directed donation [to friends or family members] because there is more than one identified patient in need’ (p. ). this creates the beauty contest dynamic, which allows donors to shop for a winner. if browsing for a winner is objectionable, it may be either that choosing between recipients is itself objectionable, or that the criteria open to use are potentially objectionable. choosing between recipients per se is plainly not objectionable; members of trans- plant staff do this all the time, and it is necessary in any trans- plant system operating in a situation of shortage. one might instead suggest that it is wrong for donors to choose, but this already occurs in the directed donations to friends or family members that are considered uncontroversial. most people who know someone needing a kidney transplant will also be aware that there are lots of other, although unidentified, people who similarly require a transplant. a potential donor may choose to donate a kidney to his/her friend/relative over the unidentified strangers. living donors in the uk are asked when they donate whether, if it transpires that their donated organ is not suitable for the intended recipient, they are happy for it to be allocated to the general pool. many will presumably say yes, but in doing so they clearly state their preference that the organ is allocated to their chosen recipient in the first instance. this is a case of choosing an identified person over an unidentified person on non-medical grounds. the situation does not necessarily seem less acceptable, however, if a person chooses between identified people. for instance if a person knows three people who need transplants—a best friend, a work colleague and someone on a donor-matching website—it is not obviously unacceptable that he/she could choose one over the others, even if this is on the basis of non-medical criteria such as being good friends with the needy patient. neidich et al appear to be concerned about organs being allo- cated according to what they term ‘normative classifications’, including clinical diagnosis, race or religion (p. ). unfortunately, they do not explain what they mean by normative classification, but one presumes that they mean something other than just organs being allocated according to non-medical cri- teria: i could quite acceptably donate a kidney to a close friend, even if there were more urgent cases or better matches on the waiting list. classifying people into friends or non-friends is a normative classification, although one that is generally consid- ered acceptable. through a website, however, donors could be choosing specific recipients because they are of a certain ethnic origin, for example. maybe, then, some normative classifications reflect unacceptable prejudice. these objectionable normative classifications can appear elsewhere within organ donation, however; so, it would be inconsistent to single out dald as unacceptable. just as someone might choose a recipient because of certain normative classifications, people are free to choose their friends or spouses on the same grounds—for instance some people will only marry members of the same religion. if norma- tive classifications shape who one is friends with then they also play an influential role in many cases where one chooses to donate an organ to a friend, and there is no guarantee that these will be ‘acceptable’ normative classifications. neidich et al’s more general concern appears to hinge on the suggestion that the beauty contest dynamic is not compatible with the altruism required from donors. they suggest that altru- ism, which is supposed to motivate organ donation, in its purest form dictates that ‘there is no shopping among patients; rather there is a donation to any patient with the capacity to benefit’ (p. ). theoretical doubts about the operation of altruism within organ donation have already been raised, but altru- ism still seems to be regarded by some as a necessary ione may recall a hoax dutch television programme that caused controversy when it pretended that viewers could vote on which patient should be given a transplant. moorlock g. j med ethics ; : – . doi: . /medethics- - current controversy o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://jm e .b m j.co m / j m e d e th ics: first p u b lish e d a s . /m e d e th ics- - o n ju n e . d o w n lo a d e d fro m http://jme.bmj.com/ requirement of ethical donation. neidich et al’s suggestion that the purest form of altruism (which presumably requires a lack of self-interest, so that the act is disinterestedly other-regarding) prohibits shopping among patients seems rather dubious, however. insistence on a pure account of altruism might still allow, or even require, a donor to shop between potential recipi- ents to ensure that his/her altruism is directed towards the right person (where this is defined in agent-neutral terms, and may not correspond with the ‘right’ person as judged by medical cri- teria). for instance, someone truly concerned about altruism and helping other people might want to ensure that his/her donated organ is given not just to anyone, but to someone who will also help other people: this seems more altruistic, rather than less. the nuffield council on bioethics considered altruism in some detail in a report on donation of bodily materials in the uk (including organs), and their definition of altruism (p. ) focuses on selflessness and lack of anticipated reward, and so says nothing that obviously prohibits choosing recipients. moreover, insisting that organ donation is only ethical if it is motivated by pure altruism will pose problems for directed donation to family members, which is difficult to conceive of as purely altruistic. in other contexts, motivation other than purest altruism is considered an acceptable reason to donate to a cause, so to claim that organ donation has some privileged require- ment of purity would require further justification. if i choose to donate £ to a testicular cancer charity rather than a breast cancer charity solely because i am a male and men’s health is of more direct concern to me, it would seem very demanding to suggest that my potentially life-saving donation was unethical and should not be permitted. it seems that it is challenging to robustly criticise dald and beauty contests from the perspective of donors without introdu- cing unjustifiable inconsistency. pure altruism is not required in other aspects of organ donation, so, it would be inconsistent to require it within dald. we routinely let donors express prefer- ence based on the normative classification that ‘someone is my friend/relative’, so, an outright ban on allocation according to normative classifications would be difficult. if the beauty contest dynamic is objectionable, it must be for other reasons. beauty contest and the recipients i have argued thus far that the beauty contest criticism is not wholly convincing when considered from the perspective of donors. i will now explore the beauty contest dynamic from the perspective of recipients. receiving organs as a competition waiting lists are the means used in the uk to manage the short- age of donated organs. factors considered when making alloca- tion decisions vary depending on the type of organ, but it is not a simple case of first-come first-served. the oxford english dictionary defines ‘competition’ as ‘the striving of two or more for the same object’, so, in a simple sense, those who are waiting for an organ transplant are competing against each other. each potential recipient on the waiting list is considered against the relevant allocation criteria, and when an organ becomes available, the patient at that time with the highest ‘score’ relative to that organ will be offered it. dald may create a beauty contest dynamic, which is plainly competitive, but if, as suggested here, competition in a simplistic sense exists in transplantation outside of dald, one must suggest why some forms of competition are considered accept- able and others are not. contrasting types of competition when organs are donated via n-dald, or the majority of deceased donation, the rules of the competition are straightfor- ward. organs are allocated according to criteria that aim to balance waiting-list mortality and transplant outcomes. although these criteria may sometimes work to the detriment of specific individuals, they balance the competing concerns of the overall system that operates in the context of a welfare state. patients who wait to receive organs via this approach to alloca- tion may accept that although they may have to wait, those with the most urgent need that can be effectively met will be given priority, and that should their need become urgent, they will be afforded this same priority. although this may still be competi- tion by definition, this approach can also be reasonably charac- terised as being cooperative. they are all relying on the same system for rescue from their plight, and patients who rely on these systems to obtain an organ are not actively competing by trying to gain priority for themselves, but are instead waiting their turn on the basis of the rules of allocation. in contrast to the orderly cooperation of impartial allocation, the competition for organs via dald is significantly more active: the behaviour of recipients can directly influence the likelihood of them receiving a transplant. instead of patiently waiting to move to the top of a waiting list due to being the best match for an organ, patients can increase their chances of being offered a transplant by creating the most compelling back-story, creating the best viral video or by directly contacting the greatest number of potential donors. by competing for organs actively and trying to get to the top of each prospective donor’s ‘list’, patients vying for organs via dald may give little concern to the plight of others who also need transplants. by taking the attitude of ‘please give an organ to me rather than anybody else’, potential recipients place their own interests ahead of others with poten- tially much more urgent need. the consequences of this will vary, but in some cases, it may result in people with urgent need dying before a transplant becomes available or having to endure extended periods of increasingly greater suffering. this may not always seem wrong—if one is in desperately urgent need of a life-saving resource, and is offered such a resource, it would be very demanding to insist that one is morally bound to pass the resource onto someone who has marginally more urgent need for that resource, particularly if it is unlikely that any more of that resource will become available. in many cases, however, the disparity in urgency of need will be much greater. someone who could wait years for a transplant trying to place themselves ahead of someone who can only wait weeks (where they are both competing for the same donor via a website) is akin to a strong swimmer trying to push a very weak swimmer away from a lifeboat even though another lifeboat will probably eventually return to pick up the strong swimmer anyway. the competition introduced by dald is potentially complex. while some people who may have, otherwise, donated via n-dald may now choose to donate to a specific recipient, there may be some donors who would only be motivated to donate by the situation of a single recipient, and would not have donated via n-dald. in these cases, those recipients should not be considered to be competing with anybody—in fact, their actions here may help others, insofar as they attract a donor who would not be willing to donate to others and remove a patient from the waiting listii (much like living-related iithis point was made by an anonymous reviewer, to whom i am grateful. moorlock g. j med ethics ; : – . doi: . /medethics- - current controversy o n a p ril , b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://jm e .b m j.co m / j m e d e th ics: first p u b lish e d a s . /m e d e th ics- - o n ju n e . d o w n lo a d e d fro m http://jme.bmj.com/ donation). despite this, it does seem plausible that dald increases the likelihood of active competition at two levels. first, if people who would have previously donated via n-dald now consider donating via dald then dald recipi- ents are actively competing with n-dald recipients. second, if potential donors visit donor-matching websites with a relatively open mind about to whom to donate, dald recipients are actively competing with one another. it is here that there is scope for objection to the organ dona- tion beauty contest on altruistic grounds. i do not wish to claim that recipients are duty-bound to give consideration to other people on the waiting list in all situations, as this may be super- erogatory in many instances. but if potential recipients are asking others to be moved to altruism by their need for a trans- plant and the person that they are, it is jarringly self-regarding for recipients to then fail to consider the situations and qualities of similar others. these recipients are asking others to do for them what they themselves are not willing to do for others. it would be difficult to defend the claim that a recipient ought to act altruistically, but this is not necessary. instead, i wish to make the more modest claim that if it is important for a dona- tion system to be driven by altruism, the behaviour of recipients should at least not counteract the altruistic underpinnings of such a system. the precise role of altruism in organ donation is subject to debate, but the nuffield council on bioethics has stated that altruism ‘helps underpin a communal, and collective, approach to the provision of bodily material for others’ needs, where generosity and compassion are valued’ (p. ), and similar claims have been made by others (p. ). the behav- iour of recipients in impartial allocation systems who coopera- tively wait their turn is aligned with the altruistic basis of the system because the waiting list is ordered to provide the best overall balance for everyone waiting for organs. by accepting that organs are allocated according to the waiting list order, patients allow for their needs and interests to be considered against the needs and interests of other patients to ensure that overall need is effectively met. the behaviour of many recipients in dald, however, can work against the role of altruism because those taking an ‘every person for him/herself’ approach would likely be much more self-serving. rather than embracing a communal and collective approach to meeting the needs of those who require transplants, dald allows recipients to actively further their own interests by leveraging their personal appeal to place their needs above those of others, potentially at a significant cost to those with more urgent need. the empirical questions and the (un)importance of altruism i have examined a specific criticism of beauty contests dynamics within organ donation, and have not given much consideration to the potential justice issues of such a dynamic. this is partly because many arguments have been explored already in the context of directed deceased donation, and also because the consequences are so unpredictable. the matchingdonors.com website claims to have matched over recipients since its cre- ation, so has provided a tiny proportion of organ donations in the usa. it is not obvious what its impact would be in the uk, but one might expect similarly low numbers unless it was exten- sively pushed as a means of promoting donation. what is espe- cially unknown is its impact on n-dald: for example, would people, who would otherwise donate impartially, now choose to donate via dald? for reasons of efficiency, impartial organ donation may be preferable to partial donation, as it allows for organs to be given to the most medically appropriate patients. if donor/recipient-matching websites cause people who would, otherwise, choose to donate non-directedly to donate directedly then this is an undesirable consequence of these sites. neidich et al and others are wise to raise concerns about the potential for injustice to occur as a result of dald, but the scale and impact of this is unknown. one possible outcome is that dald causes people to donate who, otherwise, would not do, and provides additional benefit to transplant patients. even if this benefit is distributed unevenly on unjustifiable grounds, assuming these donations would not have happened without dald then accepting them makes nobody worse off. it is with this consideration in mind that decisions should be made about dald and the future of organ donation more generally. neidich et al are correct to assert that aspects of dald are not compatible with altruism, although i have argued that this failing lies more with recipients than donors. dald may, there- fore, conflict with organ donation’s pure (and often incorrect) self-image of altruistic gifting. if altruism is the ethical guideline of acceptable organ donation then dald via websites seems at odds with this principle, and should not be permitted. but if, as has been suggested elsewhere, altruism may not be a necessary condition of acceptable organ donation then pre- venting extra donations because they do not comply with the altruistic self-image of organ donation could be looking a gift horse in the mouth. a donation and transplantation system underpinned by altruism, cooperation and selflessness may seem like the ideal, but clinging onto this ideal seems questionable if it actually results in less good being done via transplantation than the alternatives. acknowledgements i would like to acknowledge my colleagues in mesh at the university of birmingham for providing comments on an early draft of this paper. i am particularly grateful to professor heather draper for her detailed comments and support more generally. i would also like to acknowledge the two anonymous reviewers whose comments and suggestions have improved this paper in a number of places. funding this work was supported by funding from the esrc (in partnership with ahrc, epsrc, dstl and cpni) under its emoticon call (grant reference: es/ m x/ ). competing interests none declared. provenance and peer review not commissioned; externally peer reviewed. open access this is an open access article distributed in accordance with the terms of the creative commons attribution (cc by . ) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. see: http://creativecommons.org/ licenses/by/ . / references neidich em, neidich ab, cooper jt, et al. the ethical complexities of online organ solicitation via donor–patient websites: avoiding the “beauty contest”. am j transplant ; ( ): – . human tissue authority. code of practice : living organ donation. http://www.hta. gov.uk/legislationpoliciesandcodesofpractice/codesofpractice/code donationoforgans. cfm?faarea =customwidgets.content_view_ &cit_id= &cit_parent_cit_id= (accessed mar ). nhs blood and transplant. non-directed altruistic donation. http://www. 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https://www.bts.org.uk/documents/guidelines% for% directed% altruistic% donation-% final% version% - .pdf https://www.bts.org.uk/documents/guidelines% for% directed% altruistic% donation-% final% version% - .pdf https://www.bts.org.uk/documents/guidelines% for% directed% altruistic% donation-% final% version% - .pdf http://www.hta.gov.uk/newsandevents/htanews.cfm/ -huge-rise-in-altruistic-donor-numbers--says-hta.html http://www.hta.gov.uk/newsandevents/htanews.cfm/ -huge-rise-in-altruistic-donor-numbers--says-hta.html http://www.hta.gov.uk/newsandevents/htanews.cfm/ -huge-rise-in-altruistic-donor-numbers--says-hta.html http://www.hta.gov.uk/newsandevents/htanews.cfm/ -huge-rise-in-altruistic-donor-numbers--says-hta.html http://www.organdonation.nhs.uk/newsroom/statements_and_stances/statements/dutch_tv_show.asp http://www.organdonation.nhs.uk/newsroom/statements_and_stances/statements/dutch_tv_show.asp http://www.organdonation.nhs.uk/newsroom/statements_and_stances/statements/dutch_tv_show.asp http://dx.doi.org/ . /medethics- - http://www.organdonation.nhs.uk/about_transplants/organ_allocation/index.asp http://www.organdonation.nhs.uk/about_transplants/organ_allocation/index.asp http://www.organdonation.nhs.uk/about_transplants/organ_allocation/index.asp http://www.oed.com/view/entry/ ?rskey=don n&result= &isadvanced=false#eid http://www.oed.com/view/entry/ ?rskey=don n&result= &isadvanced=false#eid http://www.oed.com/view/entry/ ?rskey=don n&result= &isadvanced=false#eid http://dx.doi.org/ . /gut. . http://www.matchingdonors.com/newsletter.cfm http://www.matchingdonors.com/newsletter.cfm http://www.matchingdonors.com/newsletter.cfm http://dx.doi.org/ . /j. - . . .x http://dx.doi.org/ . /j. - . . .x http://jme.bmj.com/ directed altruistic living donation: what is wrong with the beauty contest? abstract introduction background the adverts policy position the beauty contest criticism beauty contest and the donors beauty contest and the recipients receiving organs as a competition contrasting types of competition the empirical questions and the (un)importance of altruism references consensus on changing trends, attitudes, and concepts of asian beauty original article aesthetic consensus on changing trends, attitudes, and concepts of asian beauty steven liew • woffles t. l. wu • henry h. chan • wilson w. s. ho • hee-jin kim • greg j. goodman • peter h. l. peng • john d. rogers received: june / accepted: august / published online: september � the author(s) . this article is published with open access at springerlink.com abstract background asians increasingly seek non-surgical facial esthetic treatments, especially at younger ages. published recommendations and clinical evidence mostly reference western populations, but asians differ from them in terms of attitudes to beauty, structural facial anatomy, and signs and rates of aging. a thorough knowledge of the key esthetic concerns and requirements for the asian face is required to strategize appropriate facial esthetic treatments with botulinum toxin and hyaluronic acid (ha) fillers. methods the asian facial aesthetics expert consensus group met to develop consensus statements on concepts of facial beauty, key esthetic concerns, facial anatomy, and aging in southeastern and eastern asians, as a prelude to developing consensus opinions on the cosmetic facial use of botulinum toxin and ha fillers in these populations. results beautiful and esthetically attractive people of all races share similarities in appearance while retaining dis- tinct ethnic features. asians between the third and sixth decades age well compared with age-matched caucasians. younger asians’ increasing requests for injectable treat- ments to improve facial shape and three-dimensionality often reflect a desire to correct underlying facial structural deficiencies or weaknesses that detract from ideals of facial beauty. conclusions facial esthetic treatments in asians are not aimed at westernization, but rather the optimization of intrinsic asian ethnic features, or correction of specific underlying structural features that are perceived as defi- ciencies. thus, overall facial attractiveness is enhanced while retaining esthetic characteristics of asian ethnicity. because asian patients age differently than western patients, different management and treatment planning strategies are utilized. level of evidence v this journal requires that authors assign a level of evidence to each article. for a full description of these evidence-based medicine ratings, please refer to table of contents or the online instructions to authors www.springer.com/ . keywords asian facial esthetics � asian facial features � asian facial aging � asian facial anatomy � consensus opinion � facial injectables on behalf of the asian facial aesthetics expert consensus group, the members of asian facial aesthetics expert consensus group are given in appendix & woffles t. l. wu woffles@woffleswu.com shape clinic, sydney, australia woffles wu aesthetic surgery and laser centre, camden medical centre, orchard boulevard, suite # - , singapore , singapore department of medicine, university of hong kong, pok fu lam, hong kong the specialists: lasers, aesthetic and plastic surgery central, pok fu lam, hong kong division of anatomy & developmental biology, department of oral biology, yonsei university college of dentistry, seoul, korea monash university, clayton, victoria, and skin & cancer foundation, carlton, vic, australia p-skin professional clinic, kaohsiung, taiwan regional medical affairs, allergan asia pacific, singapore, singapore aesth plast surg ( ) : – doi . /s - - - http://www.springer.com/ http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf introduction in asia, the past decade has witnessed a tremendous increase in the number of patients who request and receive facial injectable treatments, non-ablative skin resurfacing and other non-surgical procedures, compared with the number of patients undergoing esthetic facial surgery. this is probably because the public has a much greater aware- ness of the treatment options available to them. reasons for this include technological advances and improved results achievable with injectable treatments such as botulinum toxin and hyaluronic acid (ha) fillers, the increasing social acceptability of enhancing one’s appearance, increasing affordability and accessibility of injectable treatments, and the rise of the middle class in asia. most asian esthetic patients, whether young or old, prefer to avoid surgery wherever possible, and they seek natural-looking results. therefore, asian physicians have had to respond to their patients’ expectations, study, and then innovate procedures and management strategies to address the asian esthetic, including facial shape, structure and proportion, and impact of the aging process on asian faces. to date, most studies and published recommendations on the use of facial injectable treatments (especially their use in combination) reference western populations [ – ]. however, ethnic asians differ from them in both facial appearance and baseline structural facial anatomy [ – ]. the signs and rate of onset of facial aging are also different in asians [ – ]. existing published recommendations cannot be applied directly to asians. furthermore, rela- tively few published papers cited in pubmed describe the use of botulinum toxin and ha fillers in asians, and only one paper describes their combined use in the asian face [ ]. unfortunately, data from clinical trials are often not relevant to real-world practice because typically only one standardized treatment intervention is studied in one facial area; however, esthetic treatment is usually multimodal and individualized. therefore, there is a need for expert guid- ance on facial esthetic treatment of asians. to this end, the asian facial aesthetics expert con- sensus group, which comprised an anatomist, plastic sur- geons, and dermatologists from asia–pacific countries, met to discuss current practices regarding the use of non- invasive esthetic treatments in asians. as a prelude to developing consensus opinions on the use of botulinum toxin and ha fillers in asians, the group discussed con- cepts of facial beauty and attractiveness, as well as key esthetic concerns, facial anatomy, and aging in southeast- ern and eastern asians. the expert group’s goal was to identify esthetic treatments and outcomes that asian patients most commonly require, and to develop consensus opinions on how these can best be provided. proceedings of this meeting are intended to offer guidance to physicians who provide surgical and non-in- vasive facial esthetic treatment to asian patients, in the absence of published clinical evidence. in this, the first of two papers, attitudes to facial beauty in asia are descri- bed. given that a thorough knowledge of the patient’s facial anatomy and aging process is required to inform facial esthetic treatment, those factors specific to asian population groups are also discussed. asians are defined here as the diverse groups of ethnicities from east asia (e.g., china, korea, japan, hong kong, taiwan) and southeast asia (e.g., thailand, singapore, indonesia, philippines); those from the indian subcontinent are not included. methods of consensus development to determine the key trends in the type of asian patients who present for facial esthetic treatment, the patients’ key facial esthetic concerns, and the most commonly used facial esthetic treatments for each age group, members of the expert group completed a pre-meeting online survey developed by dr. steven liew. twenty-one expert group members then attended a consensus meeting in seoul, korea held on june to june , . the members of this expert group have a mean years of specialized experience in the field of facial esthetics (range – years) and treat asian patients from china, hong kong, india, indonesia, japan, korea, the philippines, singapore, taiwan, thailand, and australia. the process used to develop the consensus statements presented here was based on agreed statements created following discussions around survey outcomes, peer-re- viewed literature, and clinical experience. final versions of the statements were approved by all authors after being suggested and debated by the experts during the meeting, and modified, if necessary, while drafting the manuscript. this article does not contain any studies with human participants or animals performed by any of the authors. results: consensus outcomes the points presented here are a summary of the outcomes of discussions that took place at the expert consensus group meeting and thus reflect the consensus expert opinions of all participants. aesth plast surg ( ) : – concepts of facial beauty attractive and beautiful people of all races have distinct ethnic features, which reflect harmony, symmetry, and balance. however, when comparing the most attractive and beautiful people with their counterparts in other parts of the world, they share remarkable similarity with respect to facial shape [ , ]. facial shape is the essential key to facial beauty, with an oval face considered attractive (and youthful) by people of all racial backgrounds [ , , ]. an oval face in this context refers to a smooth egg-shaped curve outlining the perimeter of the face, with a smooth transition from the forehead through the temples, around the outside of the cheeks, preauricular region, angle of the jaw, and jawline through to the chin, without indentations or projections in the line. a well-projected nose and chin is also considered attractive. asians of all ethnicities and ages highly prize clear, unblemished, fair, and youthful skin. beauty is universal. every ethnic group has its estheti- cally strong and weak points, but on the whole, the most beautiful and attractive people of each and all races tend to look similar in terms of face shape, and harmonious deli- cacy of features, balance, and symmetry. as faces become less attractive, they display more distinct ethnic features. caucasian faces generally have more pronounced three- dimensionality with larger, more deeply set eyes, greater anterior projection of the brow, nose, maxilla, and chin. caucasians also tend to have narrower faces and greater vertical height. asians tend to have a wider face with shorter vertical height, which is flat or concave in the medial maxilla and has a lack of brow, nasal, and chin projection. on the other hand, they possess greater infraorbital volume, fuller lips, and superior skin qualities compared to caucasians, which enables them to resist environmental insults and delay physiological and anatomical signs of aging. mindful of this concept of universal beauty, regardless of race or ethnicity, physicians in asia seek to enhance ‘‘deficient’’ features and improve esthetic balance. in asians, attractiveness is achieved by aiming to create an oval facial shape, by narrowing the lower face and increasing vertical height of the face. the anterior projec- tion of the brow, medial cheek, nose, and chin is increased to improve the three-dimensionality of the face, and the appearance of the eyes is enlarged [ – ]. globalization and changing attitudes to beauty globalization has enhanced our ability to recognize, study, and create beauty in all ethnic groups (fig. ). in asians, it is now common to improve anterior projection and three- dimensionality (double eyelid, nose/cheek/forehead augmentation), increase vertical height (chin augmenta- tion), and reduce lower facial width (masseter reduction). in the past, these practices may have been perceived as an attempt to ‘‘westernize’’ the asian face. however, this is now understood to be the optimization of facial esthetic appearance within the individual’s own ethnicity. beauty is influenced by customs, traditions, and trends, and the current ideals for the female asian face include a smooth, convex forehead, large eyes, a petite nose with a raised bridge, full but not prominent lips that are propor- tionally balanced, and an oval, egg-shaped face with a neat ‘‘v-shaped’’ jawline. consensus statements on concepts of, and attitudes to, beauty • beautiful people of all races show similarity in facial characteristics while retaining distinct ethnic features. • asians are not a homogeneous group but rather comprise many varied ethnic origins, with each group having its own unique facial characteristics. • treatment to achieve esthetic changes in asians should not be viewed as an attempt at westernization, but rather the optimization of asian ethnic features, in the same way that westerners who receive lip enhance- ment, lateral malar enhancement, or skin tanning are not trying to ‘‘easternize’’ their appearance as they attempt to make up for their intrinsic ethnicity-associ- ated structural weaknesses. evolving treatment trends in asia the desire for facial esthetic improvement has always existed, but uptake was previously limited due to the expense of plastic surgery and the limited number of skilled practitioners. the results of the expert group’s pre-meeting survey showed that most asian facial esthetics patients are female, but the proportion of males seeking treatment has increased during the last decade, from % in – to % in – . the proportion of younger asian patients (i.e., aged – years) who present with esthetic concerns has increased slightly in the past years: from % in – to % in – . this may be the result of an increased sense of self identity and pride, and younger patients having more economic power, aspiration, and social independence. other reasons for this increase include (i) understanding that early use of esthetic treat- ment may prevent or reduce progress of aging; (ii) increasing awareness of esthetic procedures and treatments received by their peers and ‘‘public’’ figures in social media; (iii) increasing accessibility and affordability of aesth plast surg ( ) : – products and treatments; (iv) increasing numbers of trained esthetic physicians; and (v) the safety of injectable prod- ucts that has emerged over the past – years. key esthetic concerns in asia the expert group’s pre-meeting survey responses regard- ing the top three structural esthetic concerns among asians of different age groups is shown in table —rated according to physicians’ opinions of what patients needed to have treated and according to what physicians thought were the patients’ opinions regarding their most pressing concerns. there was generally agreement between the two sets of opinions. the survey results showed that younger patients (aged b years) most commonly request the esthetic treatments that improve facial shape and three-dimensionality. while these patients believe that they are merely seeking esthetic improvements, physicians recognize that requested treat- ments result from the underlying facial structural features common to asians (described in table ) that can con- tribute to a negative esthetic impact. as patients age, their treatment needs and preferences evolve to address issues associated with aging. those aged older than years are more likely to request treatments and procedures that improve volume loss, sagging, and wrinkles. consensus statements regarding evolving treatment trends • the available treatment options, as well as awareness of new treatments and procedures, have increased over the past decade. • the proportion of younger patients in asia who present with esthetic concerns hasincreased over thepast years. • the most common treatment concerns among younger patients (excluding skin concerns) are the result of underlying structural features that can contribute to a negative esthetic impact or relative weakness. facial anatomy and morphology in asians in asia, patients seek treatment at a relatively young age (table ) to address the perceived undesirable facial fea- tures that correlate with the underlying characteristic fig. examples of ethnic asian beauty in women from a the philippines (photo courtesy of dr. herve raspaldo); b japan (photo courtesy of dr. akiko imizumi); c korea (photo courtesy of dr. kyle seo); d indonesia (photo courtesy of dr. steven liew); and e china (photo courtesy of dr. steven liew) aesth plast surg ( ) : – structural anatomical features detailed in table . a thor- ough knowledge of the patient’s facial anatomy and age- related processes is required to inform facial esthetic treatment. the physical features of the asian face are related to specific skeletal and morphological features that differ from those of caucasians (fig. ; table ). although there is great diversity due to the ethnic variations that exist among asian populations, typical facial features can still be identified (table ; fig. ). asians tend to have a wide and short face. in profile, the face typically appears flat or, in some cases, even concave. compared with the cau- casian face, the asian face is characterized by greater intercanthal width, epicanthal folds, smaller eye fissure length, hooding of the upper eyelid/lateral brow (creating a ‘‘puffy’’ eyelid appearance), smaller oral width, greater mandibular width and a square lower face, and retruded chin. the nose has a flat dorsum, wider base, and less tip projection [ – , , ]. the lips of asians tend to be fuller than those of caucasians, with the upper lip often being more prominent. table most common esthetic concerns among asian patients – physicians’ opinions and physicians’ opinions of patients’ priorities priority opinion patient age group – years – years – years [ years physician nasal shape tear trough tear trough/malar volume loss malar volume loss/jowls patient nasal shape upper facial lines/nasolabial folds nasolabial folds jowls physician masseter volume/chin projection and shape malar volume loss/upper facial lines upper facial lines upper eyelid droop patient masseter volume tear trough upper facial lines nasolabial folds/upper facial lines physician tear trough nasolabial folds nasolabial folds tear trough/upper facial lines patient tear trough nasal shape tear trough/jowls/upper eyelid droop upper eyelid droop based on results of a pre-meeting survey of the asian facial aesthetics expert consensus group (n = responses; the responses of one australian expert who treated predominantly caucasian patients were excluded). survey question ‘‘for this question, your answer should be based on what the women need from an esthetic point of view, not on what they actually request or have treated. in your professional opinion, what are the most critical treatment areas for women aged [ – / – / – /[ ] years? choose three and rank them in order.’’ survey question ‘‘amongst your patients aged [ – / – / – /[ ] years, what are the three most common presenting esthetic concerns and complaints raised by them (without your or your staff’s guidance or intervention)? choose three and rank them in order.’’ table skeletal features and related physical characteristics/appearance of the asian face skeletal features in asians compared with those of caucasians [ – , – ] related physical appearance/clinical features in asians other characteristic facial features of asians increased bitemporal width wide forehead increased bizygomatic width wide midface increased bigonial width wide lower face retruded forehead flat forehead, slanted backward retruded orbital rims/shallow orbit puffy, heavy eyelids epicanthal folds low nasal bridge deficient anterior nasal spine flat, short nose; appearance of wider intercanthal distance retruded columella medial maxilla retrusion under-eye ‘‘dark shadow,’’ concave central midface, perialar recession and nasolabial fold, or shadows on the base of nose, broad nasal width retrusion of pyriform margin perioral protrusion full upper and lower lips bimaxillary protrusion hypoplastic mandible retruded chin includes characteristics of ethnic koreans and chinese aesth plast surg ( ) : – ethnic asians have a thicker soft tissue layer next to the most lateral point of the ala nasi, compared with cau- casians [ – ]. these factors, together with retrusion of the pyriform margin of the bony structure in asians, cor- respond with the hidden columella, wider alar base, and flatter nose characteristically observed in asians. aging in asians skin aging processes skin aging differs between asians and caucasians in sev- eral aspects. pigmentary problems such as lentigines and seborrheic keratosis are particularly common among asians, but wrinkles tend to manifest – decades later in asians than in age-matched caucasians [ , , ]. a comparison of skin aging in chinese and french popula- tions living under similar climate conditions indicated that in the chinese population, wrinkle development followed a biphasic trend, with a slow increase until the ages of – years, followed by a rapid increase thereafter [ ]. by the age of years, the wrinkle intensity in both french and chinese populations appeared similar. this is likely due to the increased melanin in asian skin affording a sun protection factor (spf) of approximately , compared with a spf of . in caucasians [ – ]. in another study that compared facial wrinkles among japanese, chinese, and thai women, the wrinkle intensity was greatest among thais, followed by chinese, and then japanese women [ ]. with thailand being the most tropical fig. comparison of asian (a, c) and caucasian (b, d) skulls. a, b anterior view. the asian skull (a) is wider overall, with greater bitemporal, bizygomatic, and bigonial width of the temple, zygoma, and mandible, respectively, compared with those of the caucasian skull (b). c, d lateral view. the asian skull (c) has less anterior projection, with a more retruded frontal bone and supraorbital ridge, recessed nasion, infraorbital rim, medial maxilla, maxillary process of the zygoma, anterior nasal spine, and pogonion of the mandible compared with the caucasian skull (d). (illustrations courtesy of prof kim) aesth plast surg ( ) : – country of the three and having a higher ultraviolet light exposure, photoaging was the most obvious reason for these findings, but other factors, including language and facial expression, also contributed to differences in wrinkle score between chinese and japanese women. factors other than spf differences that may also contribute to the reduced skin aging observed between asians and age-matched cau- casians include skin structure and thickness [ , ], diets high in antioxidants (e.g., green tea and omega- and - fatty acids) [ ], and smoking rates [ ]. sociocultural aspects, such as skincare practices and muscle use, during language articulation and facial expressions [ ] may also contribute to the differential development of dynamic wrinkles between asians and western populations. non-skin aging/physiological aging processes in asians, the physiological facial aging process involves the same dynamic and complex three-dimensional inter- play between the overlying soft tissue and its underlying skeletal structures as in western populations. facial fat and soft tissue volume loss, deflation and descent, and bony remodeling all give rise to the same common signs of aging [ – ]. retaining ligaments also play a role: as the liga- mentous system attenuates, facial fat descends [ ]. despite the similarities in the physiological processes and characteristics of facial aging among all races, differences in skeletal structural support and in the propensities of facial soft tissue to sag result in slower rates of facial aging in asians than in caucasians [ , , ]. in most asian patients, the dense fat and fibrous connection between the superficial muscular aponeurotic system and the deep fascia reduce midfacial sagging for longer, and the combination of increased superficial fat and thickened dermis lessen the incidence of superficial rhytides [ ]. eventually, however, due to the loss of dermal support (despite the initially thicker skin), the heavier malar fat pad and weaker skeletal support in the asian face contribute to tissue descent that manifests as facial sagging with aging. nevertheless, overall, the asian face retains its youthful appearance for longer due to delayed signs of skin aging and sagging, compared with age-matched caucasians [ , , , ]. consensus statement on aging • asians between the third and sixth decades age well compared with age-matched caucasians. conclusions even within the population described as ‘‘asian’’ in this manuscript, significant facial morphological differences are seen, which may underlie the scarcity of published treat- ment recommendations targeted at ‘‘asians’’ as a group. asians have facial anatomical features that may con- tribute to what they perceive as an esthetically undesirable appearance. increasing numbers of younger patients in asia are seeking cosmetic treatment specifically to address fig. a frontal and b lateral views of an asian female face illustrating some of the morphological features (wide bitemporal, bizygomatic, and bigonial distances; retruded and concave medial maxilla; puffy upper eyelids; epicanthal folds) listed in table . (photos courtesy of dr. steven liew) aesth plast surg ( ) : – these structural issues, as evidenced by the types of treat- ment that are in highest demand by different age groups [ ]. treatments to achieve esthetic changes in asians are not aimed at the westernization, but rather the optimization and beautification of their ethnic features, via the correc- tion of underlying structural characteristics that can con- tribute to a negative esthetic impact. in asians, facial aging manifests differently compared with caucasians in terms of the time course and observed changes, and asians who present for anti-aging treatments require different strategies and management techniques from caucasian patients. the intrinsic sun protection afforded by the pigment in asian skin delays photoaging, which appears to be an important factor contributing to the perception that asians age well. although asians age better extrinsically, in particular those who present for first treatment at a later age require treatment to address not only the underlying structural features that can contribute to a negative esthetic impact but also cumulative age-re- lated changes. these patients will often require combina- tion treatment and a treatment planning strategy that recognizes the complexity of the interplay between the underlying anatomical state and skin aging. acknowledgments the consensus meeting was funded by an unrestricted educational grant from allergan; however, the authors are solely responsible for the contents of this article. the authors would like to acknowledge dr. kyle seo, dermatologist, korea, for providing the photograph of the korean woman in fig. . assistance with administration of the survey, survey data analysis, and editorial preparation of the manuscript was provided by samantha santangelo, phd, of meditech media asia pacific. compliance with ethical standards disclosure dr. liew sits on advisory boards for allergan, gal- derma, and kythera and has received honoraria from allergan and galderma for delivering local and international workshops and lec- tures. dr. wu sits on advisory boards for allergan, galderma, and merz and has received honoraria from these companies for attending board meetings and delivering local and international workshops and lectures. dr. chan has received financial support for travel on behalf of allergan. dr. ho is a consultant for allergan. professor hee-jin kim received honoraria from allergan, merz, and galderma for delivering local and international workshops and lectures. dr. goodman has received honoraria for delivering lectures from and sits on advisory boards for allergan, galderma, merz, and leo. dr. peng is a speaker and/or consultant for allergan, galderma, merz, zeltiq, sanofi, ulthera, cynosure, and valeant. dr. rogers was an employee of allergan at the time of manuscript preparation. open access this article is distributed under the terms of the creative commons attribution . international license (http:// creativecommons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. appendix the asian facial aesthetics expert consensus group also includes drs. danru wang, china; yan wu, china; rashmi shetty, india; vandana chatrath, india; chytra anand, india; adri prasetyo, indonesia; akiko imaizumi, japan; nobutaka furuyama, japan; hideaki sato, japan; hong-ki lee, south korea; jonathan nevin yu, philippines; marisa pongprutthipan, thailand; and nantapat supapannachart, thailand. references . carruthers jd, glogau rg, blitzer a, facial aesthetics con- sensus group faculty ( ) advances in facial rejuvenation: botulinum toxin type a, hyaluronic acid dermal fillers, and combination therapies–consensus recommendations. plast reconstr surg : s– s . rzany b, fratila aa, fischer tc, 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plast reconstr surg : – discussion – . sykes jm ( ) management of the aging face in the asian patient. facial plast surg clin north am : – . wu wtl, liew s, chan hh, et al ( ) consensus on current injectable treatment strategies in the asian face. submitted to aesthetic plast surg . kim hj, paik dj, choi by, chung ms, han sh, hwang yi, sohn hj, chung rh, koh ks ( ) measurements of the zygomatic bones and morphology of the zygomaticofacial and zygomaticotemporal foramina in koreans. korean j phys anthropol : – . kim sh, whang e, choi hg, shin dh, uhm ki, chung h, song wc, koh ks ( ) analysis of the midface, focusing on the nose: an anthropometric study in young koreans. j craniofac surg : – . song wc, kim ji, kim sh, shin dh, hu ks, kim hj, lee jy, koh ks ( ) female-to-male proportions of the head and face in koreans. j craniofac surg : – . han sh, hwang yi, lee kh, koh ks, choi by, lee ks, lee hy, sir ws, chung ms, kim hj, kim dw, kang hs ( ) craniometric study in modern korean adults. korean j phys anthropol : – . song wc, kim sj, kim sh, hu ks, kim hj, koh ks ( ) asymmetry of the palpebral fissure and upper eyelid crease in koreans. j plast reconstr aesthetic surg : – . zhang xt, wang sk, zhang w, wang xf ( ) measurement and study of the nose and face and their correlations in the young adult of han nationality. plast reconstr surg : – aesth plast surg ( ) : – consensus on changing trends, attitudes, and concepts of asian beauty abstract background methods results conclusions level of evidence v introduction methods of consensus development results: consensus outcomes concepts of facial beauty globalization and changing attitudes to beauty consensus statements on concepts of, and attitudes to, beauty evolving treatment trends in asia key esthetic concerns in asia consensus statements regarding evolving treatment trends facial anatomy and morphology in asians aging in asians skin aging processes non-skin aging/physiological aging processes consensus statement on aging conclusions acknowledgments appendix references rieger, a. ( ) the beautiful art of mathematics. philosophia mathematica, ( ), pp. - . (doi: . /philmat/nkx ). this is the author’s final accepted version. there may be differences between this version and the published version. you are advised to consult the publisher’s version if you wish to cite from it. http://eprints.gla.ac.uk/ / deposited on: december enlighten – research publications by members of the university of glasgow http://eprints.gla.ac.uk http://dx.doi.org/ . /philmat/nkx http://eprints.gla.ac.uk/ / http://eprints.gla.ac.uk/ accepted final version. published paper in philosophia mathematica. the beautiful art of mathematics∗ adam rieger school of humanities university of glasgow glasgow g qq u.k. adam.rieger@glasgow.ac.uk abstract mathematicians frequently use aesthetic vocabulary and sometimes even describe themselves as engaged in producing art. yet aestheticians, in so far as they have discussed this at all, have often downplayed the as- criptions of aesthetic properties as metaphorical. in this paper i argue firstly that the aesthetic talk should be taken literally, and secondly that it is at least reasonable to classify some mathematics as art. ∗ancestors of this paper were presented some years ago at the universities of edinburgh and nottingham; i thank audiences there, and nick zangwill for discussions at that time. a later version was presented at a conference on aesthetics in mathematics held at the university of east anglia in december ; i thank the organizers, angela breitenbach and davide rizza, and other participants, for feedback and enjoyable discussion. introduction one might think it strange if there were a field of human activity in which the practitioners regularly describe themselves as motivated by aesthetic consider- ations, appraise each others’ work using apparently aesthetic vocabulary, and even explicitly describe what they are doing as ‘art’; yet aestheticians show no interest in the field. but such is, or was until recently, the peculiar position of mathematics. what literature that does exist on this topic — and it is rather little — has con- sisted mostly of scattered remarks made by mathematicians reflecting on their subject, with not much written in a systematic way by philosophers. the situ- ation is starting to change, but the subject of the aesthetics of mathematics is still in its infancy. my aim here is primarily to argue that there are indeed genuinely interest- ing aesthetic issues here, and that mathematics is a perfectly good topic for aestheticians to discuss. for the most part i will give an overview of the issues; many of them deserve a far more lengthy treatment than i have space for here. but i shall be arguing in a little more detail for two specific theses. firstly, that the aesthetic vocabulary used in discussing mathematics should be taken literally. if that isn’t so, the aesthetics of mathematics is a pseudo-subject, and attempts to nurture it into maturity are misguided. secondly, and more tentatively, i shall outline how it could be argued that mathematics is sometimes an art. the use of aesthetic vocabulary here are some quotations from mathematicians: i think it is correct to say that [the mathematician’s] criteria of se- lection, and also those of success, are mainly aesthetical. [von neu- mann, ] a mathematician, like a painter or poet, is a maker of patterns . . . the mathematician’s patterns, like the painter’s or poets, must be beau- tiful . . . beauty is the first test: there is no permanent place in the world for ugly mathematics. [hardy, , pp. – ] i am interested in mathematics only as a creative art [hardy, , p. ]. the mathematician’s best work is art, a high perfect art, as daring as the most secret dreams of imagination, clear and limpid. math- ematical genius and artistic genius touch one another. (mittag- leffler, quoted in rose and de pillis [ ]) i like to look at mathematics almost more as an art than as a sci- ence; for the activity of the mathematician, constantly creating as he is, guided though not controlled by the external world of senses, bears a resemblance, not fanciful i believe, but real, to the activities of the artist, of a painter, let us say. [bôcher, , p. ] why are numbers beautiful? it’s like asking why is beethoven’s ninth symphony beautiful. if you don’t see why, someone can’t tell you. i know numbers are beautiful. if they aren’t beautiful, nothing is. (erdös, quoted in devlin [ , p. ]) such instances are not at all exceptional. indeed, as rota [ , p. ] ob- serves, ‘whereas painters and musicians are likely to be embarrassed by ref- erences to the beauty of their work, mathematicians instead like to engage in discussions of the beauty of mathematics’. a little statistical evidence can be found in the empirical study by zeki et al. [ ]. of the mathematicians in the study, all but one reported emotional responses to equations. (they were not asked explicitly whether they thought equations could be beautiful, but the data is suggestive.) examples it might be useful to have some examples of (putative) mathematical beauty in front of us. here are three of my own favourites. euler’s famous formula + + +··· = π has appeared high up in some polls, coming th out of in the survey wells [ ] of readers of the mathematical intelligencer and th out of in the study zeki et al. [ ] of postgraduate and postdoctoral mathematicians. instructions for each survey were respectively ‘give each theorem a score for beauty be- tween and , inclusive’ and ‘rate the beauty of each equation on a scale from - (ugly), through zero (neutral) up to + (beautiful)’. the formula e iπ = − (or a re-arrangement of it) came top in both surveys. wells reports, though (p. ), that some awarded it a low score; he speculates that, remarkable though this equation is, those who have a reasonable familiarity with complex analysis may find it too obvious to score it highly. for a second example, here is a proof that p is irrational, remarkably not discovered until quite recently [apostol, ]. the usual proof is algebraic; this is a geometric variation. suppose p is rational, say it is m /n where the fraction is in its lowest terms. then there is an isosceles right-angled triangle with integer sides which is the smallest one possible: m m n we can show, for a contradiction, that there is another, smaller similar tri- angle, also with integer sides. construct the circle with centre and radius as shown; we claim the shaded triangle is isosceles and right-angled with integer sides. it is clearly right-angled; it is isosceles since it shares an angle of ° with the larger triangle; and its hypotenuse is of integer length since it equals m mi- nus the length of one of the shorter sides, n − m (tangents from a point to a circle are equal). which, incidentally, is actually cited as a paradigm of mathematical beauty by hardy [ , p. ]. m m n − m here is a third example. the equation z = has roots (± and ±i ). the newton-raphson method is an elementary iterative technique for finding the roots of an equation; given an approximation to a root, it (almost always) re- turns a better approximation, converging on the root if applied repeatedly. suppose we colour each point of the complex plane according to which root it converges to — what do we get? a reasonable guess would be that each point converges to the nearest root, and indeed that’s what happens if we start near to a root. but the full behaviour is quite extraordinary: of course, the mathematical beauty here is distinct from (though perhaps related to) the beauty of the picture. some whole areas of mathematics are sometimes cited as particularly beau- tiful: for example number theory and complex analysis (an area that stands out in my own memory of studying mathematics as an undergraduate). in con- trast, the theory of differential equations, which has the appearance of a ragbag of disparate techniques, has been cited as particularly ugly: ‘this is botany, not multiple coloured pictures of this sort may be found by typing ‘newton fractal’ into a search engine. mathematics’, sawyer [ , p. ]. finding necessary and sufficient conditions for beauty is not something many aestheticians think is possible. however, in the mathematical case, a number of features have come up quite frequently in discussion (for example wells [ ], hardy [ ], rota [ ]). many of these features appear in hutcheson [ ]. hutcheson considers that the key to beauty is uniformity amidst variety (i.ii.iii). he devotes an entire section (i.iii) to ‘the beauty of theorems’, claiming there is no kind of beauty ‘in which we shall see such an amazing variety with uniformity’ (i.iii.i). how widely this idea is applicable to beauty in general may be debatable, but in my view hutcheson is definitely on to something in the case of mathematics. an interplay between simplicity and complexity is typical of paradigmatic exam- ples of mathematical beauty. in the newton-raphson example, a very simple equation generates a very complex pattern. in the theory of numbers, the sim- plest building blocks exhibit endlessly intricate behaviour. another example of the same phenomenon is conway’s game of life, where there is a striking con- trast between the simplicity of the rules of generation and the complexity of the pattens they create. another aspect picked out by hutcheson is surprise, though he is careful to note it is not a sufficient condition for beauty. this seems to be playing a part in all three examples i have given; in no case would one, on seeing them for the first time, anticipate what is coming. sawyer rightly observes that the comparison is unfair to botany, which of course aims at more than a collection of specimens. for example, mcmahon [ , p. ] writes: ‘. . . there are no necessary or sufficient con- ditions for beauty when these conditions are construed as properties an object must have in order to be beautiful.’ see also sircello [ , p. ]. hardy [ , §§ – ] mentions seriousness, which he analyses as combin- ing generality and depth; the best theorems are not isolated facts, but concern, or are generalizable, to a variety of cases, and have far-reaching consequences. (hutcheson also draws attention (i.iii.v ) to cases where ‘one theorem contains a great multitude of corollaries deducible from it’, and gives an example from euclid; this seems also related to the ‘uniformity amidst variety’ idea.) the best arguments are economical; for example, a proof which argued by considering many similar cases could not be beautiful. a final aspect concerns a certain kind of understanding. for example, rota [ , p. ] talks about enlightenment, contrasting it with cases where one merely follows the steps of a proof without grasping its ‘sense’. the geometric proof of the irrationality of p above is an example of this; it makes it clear, al- most obvious, why p is irrational, by making visible the method of infinite de- scent. (these criteria can sometimes pull in different directions; barker [ , p. ] gives the example of the (second) recursion theorem, which has a short, elegant proof which, however, makes it hard to see to why the theorem is true. ) the objects of mathematical beauty if there is beauty in mathematics, what exactly is beautiful? hardy writes of beauty and seriousness as the two criteria by which mathematics is to be judged, but he is quite explicit (§ ) that they are not independent: ‘. . . the beauty of a mathe- matical theorem depends a great deal on its seriousness’. he apparently regards seriousness as either a component, or at least a necessary condition, of beauty in mathematics. an extreme case is the first published proof of the four-colour theorem [appel et al., a,b] which required the checking of different cases by computer. rota’s view (p. ) is that talk of mathematical beauty is really indirect talk about enlight- enment, a concept he (somewhat implausibly) claims mathematicians dislike and avoid dis- cussing directly because it admits of degrees. there are slick proofs of the incompleteness theorems which have the same property. taking the examples above, in the first case we have an equation or theo- rem. the beauty does not seem to depend on the exact syntactic formulation (for example, it would not matter greatly if the left hand side were replaced by a verbal description of the sum). this suggests that it is what the equation ex- presses, rather than the syntactic equation itself, that is really what is beautiful here. in the second case, although the theorem itself may also be beautiful, it is the proof which is the main focus. again, what seems important is not the exact words and pictures used, but the ideas they express. the third case is more difficult to pinpoint — perhaps it is a fact which is beautiful? what seems to be beautiful is that such a richly complex pattern can be generated by such a simple equation. in fact most of the cases cited in the literature are either theorems or proofs. the surveys carried out by wells [ ] and zeki et al. [ ] concentrate on theorems; zangwill’s objections discussed below focus on proofs, as do the col- lectors of beautiful proofs ‘from the book’ in aigner et al. [ ]. (an entire area, such as galois theory or complex analysis, is a collection or sequence of theorems and their proofs.) interestingly, there are not many claims in the literature that mathemati- cal objects are themselves beautiful. although the erdös quotation above sug- gest that numbers are literally beautiful, mathematicians do not usually refer to particular integers, or π, as beautiful. perhaps erdös should be interpreted as meaning that the totality of numbers, or the number structure, is beautiful, but even that would be contrary to the way most mathematicians talk. some geometrical figures are cited as beautiful, but this is perhaps visual rather than mathematical beauty. an unusual suggestion in rota [ , p. ] is that a definition can be beau- tiful. he gives the example of the notion of category, which facilitates the study of mathematical structure at an extreme level of abstraction. the definition of compactness in topology might provide another example. when one first en- counters this, one is puzzled as to why such an apparently complex property deserves a label; but doing so makes possible beautifully simple proofs of vari- ous theorems. rota (pp. – ) is careful to distinguish the beauty of a theory from the beauty of any particular exposition of it, and cites galois theory as an exam- ple of a beautiful theory, none of the expositions of which have succeeded in matching its beauty. he is surely right to make the distinction; moreover, of the two, it is again the beauty of the theory itself, of the content, that seems by far the more significant. (it is notable that the word ‘elegant’, rather than ‘beauti- ful’, is often used when discussing particular presentations; for example rota (p. ) uses it when describing expositions of the lebesgue integral.) the paradigmatic cases, then, all seem to be, roughly speaking at least, propo- sitional (a proof being naturally thought of as a sequence of propositions, though this may be arguable in the case of a visual proof ). is this genuinely aesthetic? if the subject of the aesthetics of mathematics is to get off the ground, it had better be that case that the judgments referred to above are genuinely aesthetic. yet some have denied this. thus rom harré has written . . . quasi-aesthetic appraisals are not a queer sort of aesthetic ap- praisal but simply not aesthetic appraisals at all . . . the satisfaction that we call peculiarly aesthetic is absent from the mathematical situation. [harre, , p. ] other writers to express hostility to, or scepticism about, the use of aesthetic vocabulary in this context being literal are zangwill [ ] and todd [ ]. the burden of proof, it seems to me, is really on the deniers. the testimony of a large number of mathematicians, who are using this vocabulary without irony, is itself a prima facie case in favour of their experiences being genuinely aesthetic. perhaps it is the case that only a small proportion of the population talk in this way, but this hardly seems relevant. the zeki et al. [ ] study re- vealed that the same areas of the brain fire when mathematicians contemplate equations they find beautiful as when they appreciate beautiful pieces of music or art, though this is suggestive rather than conclusive. there is a sense in which nothing is more convincing than one’s own in- trospection. if i reflect on my own experience in contemplating the examples above, it seems to belong to the same distinctive class as that involved in appre- ciating art and music. but this is rather unsatisfactory as a means of collectively reaching a conclusion on the matter. what actual arguments can be adduced pro and con? harré notes (p. ) the relative paucity of the vocabulary used about math- ematics, compared with other areas — we use ‘beautiful’ and ‘elegant’, but not in contrast to the mathematicians in the zeki et al. [ ] survey mentioned above, of the non-mathematicians questioned denied having an emotional response to beautiful the- orems; on the other hand, hardy [ , p. ] cites the popularity of chess, bridge and puzzles of various sorts as evidence that the ability to appreciate mathematics is in fact quite widespread. ‘charming’, ‘delightful’, ‘lovely’ or ‘handsome’. (incidentally i think harré is wrong about ‘lovely’.) todd [ , p. ] also appeals to this feature. i do not think a huge amount can be drawn from this alone, however. the range of aesthetic experiences obtainable from mathematics is no doubt less wide than those to be obtained from painting, music or literature, but this hardly shows that the experiences themselves, or the resulting appraisals, are not aesthetic. on the pro side, it is a perfectly sensible activity for a mathematician to search for better and better proofs of a result already known to be true. this seems to show that mathematicians aim at more than the pursuit of truth. what else is it? one answer is that they seek proofs that are explanatory; that give un- derstanding as to why a theorem holds, with promise perhaps of further devel- opments and applications. but another answer, consistent with the first, that has been given is that the motivation is aesthetic: much research for new proofs of theorems already correctly estab- lished is undertaken simply because the existing proofs have no aesthetic appeal. [kline, , p. ] sensory dependence a direct challenge to the idea of aesthetics in mathematics comes from the idea that aesthetic qualities are tied up with perception. for example levinson writes my proposal is that aesthetic properties . . . are higher order ways of appearing, dependent in systematic fashion on lower-order ways of hutcheson [ ] seems to be making a similar point in the second paragraph of i.iii.v. appearing . . . [levinson, , p. ] similarly zangwill [ ] has argued that ‘sensory properties are necessary for aesthetic properties’, which entails that no abstract objects have any aes- thetic properties, and hence (assuming for the moment a platonistic concep- tion) that no mathematical proofs, theorems or objects can be beautiful. actual arguments for the sensory dependence thesis seem hard to come by. it is a natural view perhaps, given the historical concentration of aestheticians on the visual arts and, to a lesser extent, music. indeed the etymology of ‘aes- thetic’ suggests dependence on perceptual properties. for zangwill the thesis fits into a wider project of aesthetic formalism. here, maybe, is an unfortunate by-product of the neglect of mathematics as a topic for aestheticians! had mathematics had the discussion it deserved, per- haps no-one would have been tempted by this thesis. but the position seems implausible independently of any mathematical considerations. for example, on literature: zangwill believes that the content of a literary work — that is, ‘what the work means, the story it tells, the characters it portrays, the emotions it evokes, the ideas it involves, and so on’ (p. ) — have no aesthetic value. and so, for example, if we read war and peace in english, virtually all of its aesthetic properties are literally ‘lost in translation’. this seems to me to be close to a reductio ad absurdum of the position. zangwill is one of the few aestheticians to have discussed the case of math- ematics explicitly. in his view, ascriptions of beauty etc. to mathematics are metaphorical. in support of this, he notes that a proof has a purpose, and ‘our a few may remain, for example names may be sonically well-chosen for their characters. zangwill himself does express some doubts (p. ) as to the correctness of the sensory dependence theory in the case of literature. admiration of a good proof. . . turns solely on its effectiveness in attaining this end, or else its having properties which make attaining the end likely. could a proof be elegant if it was invalid, or did not possess properties which tend to make proofs valid?. . . surely not’ (p. ). perhaps, though, zangwill imagines an opponent replying, this very pur- pose can give rise to dependent beauty, that is, a proof might be ‘beautiful in the way it fulfilled its function’, like the way ‘a building is beautiful as a thing with a certain function or a painting is beautiful as a representation of some- thing’ (p. ). however, he rejects this on the grounds that in genuine aesthetic cases, beauty and function can ‘come apart’. thus, ‘a building might aesthetically ex- press the function of being a library but not actually function well as a library. it might even have no potential to function well as a library (p. ).’ in con- trast ‘there cannot be proofs. . . which which are disfunctional yet beautiful or elegant’ (p. ). even if we grant him the possibility that the library may have dependent beauty of the sort described without actually functioning well as a library, zang- will seems to have overlooked that some dependent beauty may depend on ac- tual success in fulfilling the function. his argument goes through, therefore, only if (i) the only possible mathe- matical beauty is dependent beauty to be cashed out in terms of effectiveness of a proof in fulfilling its function, (ii) genuine cases of dependent beauty arise entirely from expressing a function, rather than actually fulfilling it, and (iii) in the mathematical case there is no possibility of ‘expressing’ the function com- ing apart from fulfilling it. but all of these seem highly contentious. with regard to (i), while proofs have purposes, it’s less clear that theorems or mathematical objects do (although perhaps a theorem has some kind of rep- resentational purpose, as i discuss below). in addition, it seems misconceived to set things up in this way: there is surely more to the (purported) beauty of a proof than its simple effectiveness, or else any two correct proofs of the same theorem would be on a par. (ii) seems false; a library could have dependent beauty in virtue of the way it actually functioned as library, and a painting in virtue of accurately depicting its subject. and (iii) is also dubious; a proof might perhaps be strictly invalid but still contain valuable ideas which made it beau- tiful. overall, therefore, zangwill’s remarks are unconvincing. (for a more detailed critique of zangwill’s view, see barker [ ].) beauty and truth the most serious threat to the literal interpretation of the aesthetic vocabulary arises from the observation that mathematicians are ultimately concerned with producing truths; hence, even if they describe themselves as pursuing beauty, it is dubious that they really mean it. thus todd [ ] is sceptical that aesthetic appraisals should be taken literally. what appear to be aesthetic judgments are, he suggests, really disguised epistemic ones. he presents (p. ) a dilemma for the literalist: either there is ‘some im- portant connection between epistemic and aesthetic factors in theory assess- ment’ (a conjunctive view), in which case ‘it is difficult to see what independent role aesthetic factors could play in theory assessment, or indeed what the dif- euler’s original proof of the π formula, in which he lacked the relevant results on infinite products, might provide an example. ference between aesthetic and empirical criteria of assessment actually is’; or else ‘they are essentially unconnected’ (the disjunctive view), in which case ‘problems also surround the mysterious role that aesthetic factors could play in theory assessment, particularly in respect of the problematic idea that theories could somehow be beautiful but not true’. surely some version of a conjunctive view is correct; beauty and truth are importantly connected (though the relationship is certainly more complex than identity, as keats would have us believe). it does seem at least roughly right that truth (or validity in the case of a proof ) is a necessary condition for beauty. the euler proof mentioned earlier is invalid as it stands, but can be made rigorous by filling in some gaps. there could perhaps be a ‘near miss’ theorem that was untrue as stated but possessed some beauty — but it would be flawed, like a cracked vase, and the falsity certainly sharply reduces the aesthetic value. kivy [ ] suggests that the beauty of theories should be thought of by analogy with representational painting: the scientist does not admire a theory’s beauty and then admire it or not admire it for its truth. it is admired for how beautifully it is true; for how beautifully it represents nature. (p. ) if we take ‘nature’ in the case of mathematics to be ‘mathematical reality’, we have here, i think, a promising way to make sense of mathematical beauty. and one that is perfectly consistent with its relation to truth. for it seems the aesthetic value of a representational painting depends on the the success, the todd’s argument is framed in terms of empirical science, but is intended to apply to math- ematics as well. kivy’s main focus is also on the empirical sciences, but again can be applied also to the mathematical case for most purposes. truthfulness of the representation (of course, this should not be understood in a crude way as ‘the more like a photograph, the better the painting’; but a successful painting says something illuminating and true about how its subject appears, or how one experiences seeing it). kivy goes too far in his ‘conjunctive account’; he says that beauty and truth cannot be ‘prised apart’ (p. ), and comes close to endorsing keats at the end of his paper. but whether or not we can have beauty without truth, we can certainly, in mathematics, have truth without beauty. todd’s charge that kivy’s conjunctive account does not keep the aesthetic sufficiently distinct from the epistemic is just. it is not true though, as todd claims (p. ) that ‘science just aims to get it right’. truth isn’t all there is. there is a position which avoids both the horns of todd’s dilemma: beauty and truth are neither independent, nor to be iden- tified. indeed, in the latter, more concessive, part of his paper, todd counte- nances the possibility of ‘explaining the aesthetic value of proofs and theories in terms of the way in which their epistemic content is conveyed’ (p. ), which suggests a position not far from kivy’s, though without the near-identification of the true and the beautiful. exactly what is the connection between beauty and truth is a large question! if, for example, seeking beauty is somehow to be a guide to finding the truth, it is an urgent matter to explain why. i shall have a little more to say about it in paradigmatic examples might be the kind of theorems we find in combinatorics, giving complex formulae for such things as the number of ways of tiling polygons with other polygons; in addition valid but unattractive proofs such as the one of the four-theorem cited earlier. this perhaps also serves as an example of quite a beautiful theorem ( th on wells’ survey) without a beautiful proof; rota (p. ) cites the prime number theorem, giving the asymptotic density of the primes, as another such example. james mcallister has developed, over a series of publications, an elaborate theory which section . but that mathematical beauty is enmeshed with truth does not seem a good reason to think that it is not really beauty at all. aesthetics and the metaphysics of mathematics i have suggested above a way in which thinking about mathematics might have consequence for aesthetics, in telling against the sensory dependence thesis. an interesting questions is whether we might have interaction in the other di- rection: might aesthetic considerations have implications for more mainstream philosophy of mathematics? if propositions are the locus of beauty, then this suggests that is no easy route from aesthetical considerations to conclusions about the ontology of math- ematics. it seems euler’s π theorem can have beauty whether one platonisti- cally regards it as being about an externally existing realm of mind-independent mathematical objects or, alternatively, about a world of fictional objects created by human activity. the croce-collingwood theory, according to which artworks are mental, has interesting parallels with the intuitionism of brouwer, according to which mathematics consists of ‘mental constructions’. and the theories run, i think, into parallel difficulties, that in each case what goes on in one’s head seems to be answerable to something external, in a way that the theories struggle to ac- count for; there are wrong ways to interpret a picture, and there are false math- ematical propositions. connect beauty and truth in science and mathematics, via what he calls the ‘aesthetic induc- tion’ (see for example [ ] and [ ]). i do not have space to discuss mcallister’s work here, but it is addressing exactly the questions i think need exploration. breitenbach [ ] expands some brief remarks of kant into a worked out account of the beauty of mathematical proofs within a kantian framework. ac- cording to breitenbach’s account, our experience of mathematical beauty is grounded in ‘our felt awareness of the imaginative processes that lead to math- ematical knowledge’ (p. ). i cannot here discuss breitenbach’s intricate account in the detail it de- serves. by focussing on mathematical demonstration as a human activity, bre- itenbach is able to go some way towards accounting for the roles of surprising- ness and understanding in mathematical beauty. an account focussing only on objects and their properties will surely struggle to do this. on the other hand, the kantian framework explicitly allows only proofs to have beauty, and not theorems. this is because, for kant, a cognitive judg- ment, such as is involved in contemplating a theorem, differs essentially from an aesthetic one (in the first, but not the second, a ‘synthesis of the sensory manifold’ is ‘subsumed under concepts’ — see p. ). this seems a serious weak- ness of the kantian account, since the position that proofs but not theorems can be beautiful does not accord well with the experience and testimony of mathematicians. (it is not simply that we need to seek a different account for the beauty of theorems — such an account is ruled out in the kantian system.) it would be an interesting project to see to what extent breitenbach’s insights could be preserved in a way that was less embedded in the kantian approach. it is informal proofs that are intended here, and in particular in geometry. the question as to how far the account is extendible to other areas of mathematics is raised by breitenbach herself (pp. – ). breitenbach describes the contrast as existing between proofs, on the one hand, and math- ematical objects and their properties, on the other, but that does not seem quite right. it is presumably not the (universal) properties such as primeness, straightness etc. which might be beautiful, but rather particular objects’ having them, that is, something propositional. what of someone who wanted to defend the beauty of mathematical the- orems and proofs, but rejected propositions? one way out might perhaps be to argue that one can have an aesthetic experience without an object, analo- gously to adverbialist theories of perception. perhaps it can simply be beautiful that something is the case without there being any object which is beautiful. i do not know whether a plausible theory could be developed along these lines, but it would be interesting if so and might have applications in other areas of aesthetics. mathematics as art let us take stock. in arguing for the literalness of aesthetic appraisals in math- ematics i made use of the analogy with representational painting, pointed out by kivy, and the kinship with literature since the bearers of beauty are, in most cases, propositional. but one can now ask a further question: is mathematics, like painting and literature, an art? this question, of course, is separate from the question of whether mathematics has aesthetic properties. it could be that mathematical beauty exists but is natural beauty, like the beauty of a landscape or a flower. though several mathematicians, including some quoted above, have talked about mathematics as an art, as far as i know, no-one has explicitly defended this thesis philosophically. it certainly seems implausible that all mathematics should be art; in particular, a lot of applied mathematics will not be. but in this a referee suggests another route for the rejecter of propositions: to find beauty in the lin- guistic expressions. but as argued above (section ) mathematical beauty seems primarily lo- cated in the content of theorems and proofs, rather than the particular way that content is ex- pressed. mathematics is like several other activities (not all writing or drawing is art, for example). how might one argue for the thesis that some mathematics, of the pure sort which its practitioners say is pursued for aesthetic reasons, is an art? in contrast to the case of beauty, a considerable amount of philosophical work has gone in to attempts to define art, without any great agreement (in this, of course, art is hardly exceptional). it would be an interesting task to assess whether mathe- matics counts as art according to some of the main theories that have been put forward, but that would hardly give us a conclusive answer, and is not some- thing i shall attempt here. in any case, perhaps there are no necessary and sufficient conditions for art. wittgenstein’s ‘family resemblance’ idea may be helpful here: i am cau- tiously inclined to think that the parallels, noted above, between mathemat- ics and both representational painting and literature, combined with the gen- uinely aesthetic elements in mathematics for which i have already argued, sug- gest that mathematics is sometimes an art. the main consideration on the other side seems once again to be that truth plays too great a role in mathematics. but as in the discussion of beauty and truth above, the case of representational painting suggests this is hardly deci- sive. not only is the representational accuracy of a painting no obstacle to its being art, it is (understood, as previously mentioned, in a non-simplistic way) essential to the aesthetic value of a painting. the case of literature is more complicated. with prose at least, paradig- matic examples of literature-as-art tend to be fictional. (on some non-platonist views, mathematics itself is a kind of fiction and the objection loses its bite; for an explicit defence of a such a view, see bueno [ ].) we are more likely to regard a novel as art than a work of biography, history or travel-writing. there are several points to make here. poetry always seems to be art, whether or not its subject matter is fictional. a landscape painting does not count as art only if the landscape depicted is fictional. sometimes we do regard works of history or biography as art; and here, as in the case of representational paint- ing, not only is the constraint to be truthful no obstacle to their being art, but its violation would be a serious flaw. finally, even fiction is related to truth in an indirect way; the faithfulness of a novel to human nature in particular, and also to such things as the era in which it is set, is of direct relevance its aesthetic value. mathematics, then, is one of a family of activities which tell us how things are, in a way that is aesthetically valuable. it seems no travesty to call such a practice ‘art’. hardy, who sees no contradiction between his platonism [ , pp. – ] and explicitly stating that mathematics is an art (p. ), raises an interesting issue which points to a difference between mathematics and the other arts i have been discussing. he quotes (p. ) with approval houseman’s comment that ‘poetry is not the thing said but a way of saying it’, and of the lines from richard ii ‘not all the water in the rough rude sea/can wash the balm from an anointed king’ comments ‘could lines be better, and could ideas be at once more trite and more false?’. mathematics works only with ideas, thinks hardy, and is hence ‘more permanent’. hardy does bring to light an important contrast here. in mathematics, the main aesthetic value lies with the thing represented, not the representation. (sometimes a particular presentation or formulation may be notable for its ele- gance, but it is mainly the theorems or proofs themselves that are seen to have the aesthetic value.) this seems to mark a distinction between mathematics and literature, and also representational art, where we talk of the beauty of the painting, not its subject. this disanalogy might be seen to threaten the status of mathematics as art. but even if correct, it does not seem a conclusive reason why mathematics can- not be art. there can be art in selecting which pieces of (mathematical) reality to display, as du sautoy discusses in a recent popular piece in which he is com- paring mathematics and music: most people’s impression is that a mathematician’s job is to estab- lish proofs of all true statements about numbers and geometry . . . what is not appreciated is that mathematicians are actually engaged in making choices about what is being elevated to the mathematics that deserves performance in the seminar room or conference hall. the proof of fermat’s last theorem is considered one of the great mathematical opuses of the last century, while an equally compli- cated calculation is regarded as mundane and uninteresting. it is the narrative journey that the first proof takes you on that makes this proof worth telling. [du sautoy, , p. ] in any case, the contrast does not seem sharp. arguably the most valued paintings have beautiful subjects, as well as being themselves beautiful repre- sentations; part of the what the artist is commended for is having successfully conveyed a beautiful part of reality. and it seems to me hardy is wrong about the lines of shakespeare; the lines would be finer, were the thought expressed by them true and insightful. i argued above that part of the aesthetic value of literature is genuinely propositional, survives translation, and contra house- man, is the ‘thing said’, rather than ‘the way of saying it’. so the disanalogy with mathematics is less than hardy suggests. conclusion in the course of this survey, i have argued firstly that aesthetic appraisals of mathematics should be taken literally. that the practioners of mathematics use aesthetic vocabulary apparently intending it to be understood non-metaphorically suggests the burden of proof is on those who deny the genuineness of the aes- thetic appraisals. but neither an argument from sensory dependence, nor one maintaining that mathematics is too concerned with the pursuit of truth to be an aesthetic activity, seem convincing. moreover, mathematics seems to have enough in common with paradig- matic arts such as painting and literature that there is a case for counting at least some mathematics as itself an art. i have only sketched how one might argue in more detail for these claims, but if i am correct, then mathematics is an area of human activity which de- serves a lot more attention from aestheticians than it has so far had. and even if the claims are false, articulating exactly why promises to be illuminating in indeed, hardy himself comes close to recanting a few pages later (at the end of § ). the form of literature closest in analogy to a mathematical theorem is perhaps the wildean epigram: for example, ‘a man cannot be too careful in the choice of his enemies’, from the pic- ture of dorian gray. we might note the element of surprise; the truth of the thought expressed; and that it survives translation. clarifying our concepts of art and the aesthetic. either way, there are plenty of interesting avenues for further exploration in the area. references martin aigner, günter m. ziegler, karl heinrich hofmann, and paul erdös. proofs from the book. springer, berlin, . tom m. apostol. irrationality of the square root of two — a geometric proof. american mathematical monthly, ( ): – , . kenneth appel, wolfgang haken, et al. every planar map is four colorable. part i: discharging. illinois journal of mathematics, ( ): – , a. kenneth appel, wolfgang haken, john koch, et al. every planar map is four colorable. part ii: reducibility. illinois journal of mathematics, ( ): – , b. john barker. mathematical beauty. sztuka i filozofia (art and philosophy), : – , . maxime bôcher. the fundamental conceptions and methods of mathematics. bulletin of the american mathematical society, ( ): – , . angela breitenbach. beauty in proofs: kant on aesthetics in mathematics. eu- ropean journal of philosophy, ( ): – , . otávio bueno. mathematical fictionalism. in new waves in philosophy of math- ematics, pages – . springer, berlin, . keith j. devlin. the maths gene: why everyone has it, but most people don’t use it. weidenfeld & nicolson, london, . godfrey harold hardy. a mathematician’s apology. cambridge university press, . rom harre. quasi-aesthetic appraisals. philosophy, ( ): – , . francis hutcheson. an inquiry into the original of our ideas of beauty and virtue: in two treatises ( nd edition). j. darby...[and others], london, . peter kivy. science and aesthetic appreciation. midwest studies in philosophy, ( ): – , . morris kline. mathematics in western culture. oxford university press, . jerrold levinson. aesthetic properties. proceedings of the aristotelian society, supplementary volumes, lxxix: – , . james w. mcallister. beauty and revolution in science. cornell university press, . james w. mcallister. mathematical beauty and the evolution of the standards of mathematical proof. in the visual mind ii, pages – . mit press, cam- bridge, ma, . jennifer a. mcmahon. aesthetics and material beauty: aesthetics naturalized. routledge, . john von neumann. the mathematician. in mortimer jerome adler and robert b. heywood, editors, the works of the mind, pages – . univer- sity of chicago press, . nicholas j. rose and john de pillis. mathematical maxims and minims. rome press, raleigh, nc, . gian-carlo rota. the phenomenology of mathematical beauty. synthese, ( ): – , . marcus du sautoy. music by numbers. bbc music magazine, ( ): – , . walter warwick sawyer. prelude to mathematics. penguin books, har- mondsworth, . guy sircello. new theory of beauty. princeton university press, . cain s. todd. unmasking the truth beneath the beauty: why the supposed aes- thetic judgements made in science may not be aesthetic at all. international studies in the philosophy of science, ( ): – , . david wells. are these the most beautiful? the mathematical intelligencer, ( ): – , . nick zangwill. the metaphysics of beauty. cornell university press, . semir zeki, john paul romaya, dionigi m. t. benincasa, and michael f. atiyah. the experience of mathematical beauty and its neural correlates. frontiers in human neuroscience, : – , . doi: . /s - ( ) - book reviews area it does not cover concerns the trickier questions into their schedule. although there will be a tendency that young investigators face when submitting their first to feel like this is the last thing that a new investigator grant. for instance, many pis do not know how to direct should spend time doing, the book is well worth the their grant to the appropriate study section or when they time. the book replaces that senior faculty mentor who should contact a program official for advice. however, is not around when a crisis strikes. another advantage as pointed out in one of the quotes, there is 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the reader gets a broad overview about wave, we have witnessed the inescapable withering ofall the key issues in starting a lab. however, the general- research of the sort that is based purely on microscopicizations mean that any unusual or difficult issues, such observations. in their place, we have seen the emer-as how to handle sexual harassment or maintain lab gence of many exciting studies that have elegantly em-enthusiasm, are not covered. although some of the braced the new molecular tools to peer deeper into whatdeeper issues are not discussed, a similar book by kathy lies beneath the chromosome.barker called at the helm, a laboratory navigator is so what have we learned about the chromosome?much more focused and thorough about complicated for one, we have sequenced many genomes and nowpersonnel issues. since barker’s book does not include know a great deal about the nucleotide sequence of theissues described in academic scientists at work, such genes that are dotted from one end of a chromosomeas how to obtain funding or how to organize a class, to the other. we know about what types of dna and,they are an excellent complementary set. to a much lesser extent, proteins cohabit the longitudinalacademic scientists at work is an extremely fast and easy read, so junior pis will have an easy time fitting it segments of a chromosome. we have become ruthlessly cell good at knocking these proteins about in cell culture or needed modern treatment with molecular tales. it is a text attempting to cover practically everything to do within whole model organisms to see what any disastrous consequences might tell us about their functions. we chromosomes and, generally speaking, has done a very fine job in that regard. understandably, given that it ishave become obsessed with mechanistic insights, not to mention little choice if we want to woo the big journals a mere pages, the book falls short on detail in many places for which individual books and major reviewsand granting bodies; thankfully, though, we have learned quite a few things about the mechanisms for many of can be and have been written, but through clever and liberal use of tables and figures, chromosomes: organi-the processes. and what remains to be learned about the chromo- zation and function has managed to capture a large amount of information, with adequate referencing andsome? the answer is a definite “whole lot more.” to this end, we should be, and some already are, critical web linkages to extend its depth. the inclusion of an impressive number of real life micrographs and imagesthat the “reductionist approaches” that we have grown to depend so much on, allow us to look at only one or a of chromosomes doing various things is particularly pleasing, not only because of the illustrative utility ofvery limited number of components at a time, in isolation from most other possible players. they do not help us these pictures, but also for the vivid reminders they provide of the aesthetic appeal of the subject.to capture and interdigitize all the important in-between pieces that are still missing from the big picture. take the first chapter provides some historical background and reminisces about the few fascinating but largelya couple of examples that have been covered in adrian sumner’s book, chromosomes: organization and func- ignored years in the mid-to-late s when four of the most commanding discoveries of modern biology hadtion. for the centromere: although we have now identi- fied a plethora of proteins on this structure, we still have their unparalleled beginnings in remarkably close suc- cession: the publication of the principles of genetics inlittle idea as to what many of them actually do, especially concerning how they interact physically or temporally, by mendel, the isolation of an impure form of dna in by miescher, the description of mitotic chromo-and what other players are missing, to enable us to reconstruct the complete pathways for both the assem- somes in by schneider, and the proposal of the theory of evolution by darwin in the s (althoughbly and proper workings of this important structure. or take another example: although we have known for a that last is not mentioned in this book). in , we commemorate years of cracking the dna structure,considerable time now about the basic components of a nucleosome and how the chromatin undergoes the but those early discoveries or so years ago deserve every bit as much to come to the forefront of our mind.initial - to -fold packing (up to the solenoid stage), we struggle to demonstrate how it reaches its final chapter two gives an overview of the events that occur at mitosis and meiosis and provides a useful back- , -fold state of condensation—never mind the even less understood process of decondensation. further ground for subsequent chapters. the next few chapters take us from the dna molecule through to its assemblymethodological and technological advancements such as those along the lines of proteomics (tyers, m., and into chromatin, interphase chromosomes, and finally mi- totic and meiotic chromosomes. these chapters providemann, m. [ ]. nature , – .), physical and temporal imaging, and mathematical and computational a good mix of tidbits of information—such as how many nucleotides and genes are found in various species,modeling (chitnis, a.b., and goodhill, g.j. [ ]. cell , – .), will clearly be necessary to address the and how long and how thick the dna and its more compacted chromatin and chromosome relations are—big-picture tasks. the recent launch of a pilot encyclo- pedia of dna elements (encode) project by nih, aimed and more substantial discussions of known mecha- nisms and individual protein involvements in processesat testing and comparing methods for the exhaustive identification and verification of functional elements in such as: mitotic start control, dna replication, spindle checkpoint, sister cohesion and separation, meioticthe human genome, is a step in the right direction. the story so far is much like that of frodo, setting out crossing over, chromatin assembly and modification, arrangement of interphase chromosomes, and how theon a journey through a massive and daunting labyrinth in order to deliver the ring of mordor to the fires of mount cell deals with different types of dna damage. these accounts, while inevitably reflecting the incompletenessdoom. frodo now has the unenviable task of learning everything he can about the labyrinth (primary and inter- of information in many areas, have quite unmistakably succeeded in portraying the impressive advances weacting pathways), what players (genetic and epigenetic) are interested in the journey, with whom he can form have made. the book then turns to specific features of the chro-partnerships (intermolecular complexing and networking), what he and his partners can do (functional understand- mosome, devoting a chapter each to euchromatin, het- erochromatin, sex chromosomes, imprinting, nucleolusing of each player), the loyalty and worth of his fellow travelers (some may have many and variable talents organizer regions, centromeres, telomeres, lampbrush chromosomes, and polytene chromosomes. these chap-or agendas, and others may be dispensable), and any obstacles confronting him (regulatory and inhibitory ters are full of useful information of both descriptive and mechanistic kinds. several tables list large numbers ofmechanisms). for the sake of humankind, elves, dwarves, and hobbits alike, frodo will, of course, gallantly and protein components involved in various processes. al- though the lists in these tables are not exhaustive andpainstakingly inch his journey forward. having access to useful and accurate intelligence will definitely help do not provide enough information to give the reader a real understanding of the roles of the individual compo-his journey, and here enters sumner’s book. the book dwells heavily on many long-unresolved nents, they nonetheless serve to inform on the range of proteins that have been discovered. these chapters alsotopics relating to chromosomes and gives them a much- book reviews contain a wealth of information that will help the reader to appreciate both the constancy and the diversity of chromosomal phenomena through the phylogeny. the last three chapters offer interesting reading on the role of the chromosome in evolution, disease, and genetic modification and therapy (through chromosome engineering). these pages provide a welcome reprieve from the hard facts of the earlier chapters, turning to the more speculative arena of evolution, as well as possible clinical and practical implications of chromosome biology. overall, this is an excellent book, written in an easy- to-read style and packed with interesting and accurate information that both novices and learned scholars of chromosome and cell biology will find useful. it takes on many fast-changing topics, but much of the carefully presented information in this book should endure the inevitable onslaught of new research findings. the book could have been strengthened in many areas—for exam- ple, by providing a more in-depth evaluation of weak or missing links, discussing the different chromosomal structures more interactively (such as the significance of common proteins or shared interphase arrangements), highlighting the role of epigenetic influences on and plasticity of some of the structures, indicating possible future research methodologies and directions, and per- haps offering some predictions as to what the field may hold in the years to come. but to insist on these would be to pick faults for their own sake, and to unfairly de- tract from a job that is already well done. whether read from cover to cover or used as a handy reference, this is a book that will educate on the beauty and complexity of the chromosome. and finally, then, to those em- barking on the journey with frodo—good luck! k.h. andy choo murdoch childrens research institute royal children’s hospital flemington road parkville australia microsoft word - lewis,p.quantum_sleeping_beauty_(revised).doc quantum sleeping beauty peter j. lewis plewis@miami.edu the sleeping beauty paradox in epistemology and the many-worlds interpretation of quantum mechanics both raise problems concerning subjective probability assignments. furthermore, there are striking parallels between the two cases; in both cases personal experience has a branching structure, and in both cases the agent loses herself among the branches. however, the treatment of probability is very different in the two cases, for no good reason that i can see. suppose, then, that we adopt the same treatment of probability in each case. then the dominant ‘thirder’ solution to the sleeping beauty paradox becomes incompatible with the tenability of the many-worlds interpretation. consider first the many-worlds interpretation of quantum mechanics, and in particular what happens when an observer measures the x-spin of a spin- / particle whose state is an eigenstate of z-spin. according to the many-worlds interpretation, the observer branches into two successor observers, one of whom sees the result ‘spin up’ and the other of whom sees the result ‘spin down’. call the original (pre-measurement) branch b , the branch in which the observer sees ‘spin up’ b , and the branch in which she sees ‘spin down’ b . compare this to a simplified version of the sleeping beauty paradox. sleeping beauty is woken up on sunday, and told the following: “we will wake you for an hour on monday, and for an hour on tuesday, and on monday night we will administer a drug that will cause you to forget the monday waking.” her room contains no indication of what day it is. call the time at which she is awake on sunday t , on monday t , and on tuesday t . note the parallels between the two cases. in the many-worlds case, the agent at b is straightforwardly psychologically continuous with the agent at b , and straightforwardly psychologically continuous with the agent at b ; however, the agents at b and b are not psychologically continuous with each other. similarly in the sleeping beauty case, the agent at t is straightforwardly psychologically continuous with the agent at t and with the agent at t , but the agents at t and t are not straightforwardly psychologically continuous with each other due to the memory erasure. that is, in each case the personal experience of the agent exhibits a branching structure. furthermore, note that in each case the agent gets lost in this branching structure. this is clearer in the sleeping beauty case; when she wakes up, she no longer knows whether it is monday or tuesday. that is, at t and t she is uncertain of the truth-value of some self-locating beliefs, such as “today is monday” (elga ). she could use a probability measure to quantify this uncertainty; presumably she should assign a probability of / to “today is monday” on the basis of some kind of indifference principle. in the case of the many-worlds interpretation, the parallel uncertainty can be produced by supposing that the observer is blindfolded; at b and b , she knows that the measurement has taken place, but she doesn’t know whether the result is ‘up’ or ‘down’ (vaidman a). again, she is uncertain of the truth-value of some self-locating i will drop the term ‘subjective’ from now on; all probabilities should be understood as subjective probabilities, unless specified otherwise. that is, an interpretation in the tradition of everett ( ). see in particular wallace ( ). elga ( ). i have modified elga’s example to make the parallels between the two cases clear; i return to the original version below. beliefs, such as “the result is ‘up’ in this branch” (ismael ). and again, she could use a probability measure to quantify this uncertainty; she should assign a probability of / to the cited belief, on the basis of the born rule. hence in both the many-worlds case and in the sleeping beauty case, there is a branching structure to subjective experience, which induces a loss of self-location information, and the resulting uncertainty can be quantified using a probability measure. however, there is also a significant difference between the two cases, namely in the treatment of probability before the branching event. according to the many-worlds interpretation of quantum mechanics, the observer should assign a probability of / to each measurement outcome even at b . that is, the treatment of probability in the many-worlds case is just as if exactly one of the two outcomes occurs, where each outcome has an objective chance of / . but there is no analogous pre- branching probability assignment in the sleeping beauty case; there is no sense in which sleeping beauty at t should assign a probability of / to each of monday and tuesday. to what beliefs could she assign such probabilities? “today is monday” has a probability of at t ; she knows that today is sunday. “i will wake up on monday” has a probability of at t ; she knows that she will wake up on monday (or at least, that she is psychologically continuous with someone who will wake up on monday). there are no obvious candidates for a belief about monday to which sleeping beauty should assign a probability of / at t . hence the treatment of probability in the sleeping beauty case is not just as if she is woken up on exactly one of monday and tuesday with an objective chance of / each. of course, similar considerations can be raised in the many-worlds case, too. to what beliefs, at b , can the observer assign a probability of / ? “the result is ‘up’ in this branch” has a probability of at b , since this branch (b ) contains no measurement results. “i will see the ‘up’ result” has a probability of , since the observer knows that she will see this result (or at least, that she is psychologically continuous with someone who will). again, there are no obvious candidates for a belief concerning the results to which she should assign a probability of / at b . nevertheless, many authors have argued that a pre-measurement probability assignment of / to the two results is appropriate in the many-worlds case. saunders ( ) and wallace ( ) argue that the branching structure of the observer’s experience makes the observer genuinely uncertain concerning what will happen to her; hence it makes sense for her to assign a probability of / to “i will see the ‘up’ result” at b . vaidman ( a) argues that even though the observer is only genuinely uncertain after the measurement, nevertheless she should act as if she is uncertain even before the measurement, and this underwrites an effective probability assignment of / to “i will see the ‘up’ result” at b . papineau ( ) and greaves ( ) argue that a probability assignment need have nothing to do with uncertainty; a probability assignment of / to “i will see the ‘up’ result” at b indicates how much the observer cares about her successor at b relative to her successor at b . my goal here is neither to defend nor to attack these argument strategies, but merely to note that they all remain controversial, and that if any such strategy works, it ought to work just as well in the structurally similar sleeping beauty case. that is, given the parallels between the two cases, then all other things being equal, we should expect the two cases to be covered by a uniform account of probability. but as it stands, the treatments of pre-branching probability are the born rule equates the probability of a branch with the square of its quantum mechanical amplitude. it might strike readers as suspicious that the justification for the probability assignment differs between the two cases; i return to this issue below. not parallel. this leaves us with two options—applying the treatment of pre-branching probability from the sleeping beauty case to the many-worlds case, and applying the many- worlds treatment to the sleeping beauty case. according to the first option, the treatment of probability in the sleeping beauty case is correct; sleeping beauty should assign a probability of / to both “today is monday” and “today is tuesday” at t and at t , but she should assign a probability of to both “i will wake up on monday” and “i will wake up on tuesday” at t . applying this to the many-worlds case, the (blindfolded) observer should assign a probability of / to both “the result is ‘up’ in this branch” and “the result is ‘down’ in this branch” at b and b , but she should assign a probability of to both “i will see the ‘up’ result” and “i will see the ‘down’ result” at b . the trouble with this option is that it fatal to the many-worlds interpretation of quantum mechanics; the observer’s pre-measurement predictions contradict the born rule, which forms the empirical heart of quantum mechanics. that is, quantum mechanics requires that non-trivial probabilities be assigned to measurement results before the measurement has occurred, and if the many-worlds interpretation cannot deliver such probabilities, then it is untenable as an interpretation of quantum mechanics. indeed, this is precisely why the authors cited above take such pains to try to justify pre-measurement probability assignments in the many-worlds interpretation. so let us consider the second option, namely that the treatment of probability by the advocates of the many-worlds interpretation is correct. according to this option, the quantum observer should assign a probability of / to both “i will see the ‘up’ result” and “i will see the ‘down’ result” at b , so analogously, sleeping beauty should assign a probability of / to both “i will wake up on monday” and “i will wake up on tuesday” at t . that is, in both cases the branching process is treated as if it were an instance of objective chance, where just one branch occurs. this is highly counter-intuitive in the sleeping beauty case; as elga notes, on sunday sleeping beauty was “already certain that [she] would be awakened on monday” ( , ). but perhaps our intuitions here are wrong, and perhaps one of the arguments mentioned above for the many-worlds case can show why they are wrong. however, more is at stake here than our intuitions. to see this, consider the full sleeping beauty paradox, rather than the simplified version considered so far. on sunday, sleeping beauty is told that a coin will be tossed. if the coin comes up tails, then she will be woken up on monday and on tuesday with memory erasure in between, as in the simplified version. if the coin comes up heads, then she will be woken up on monday alone. (it doesn’t matter for present purposes if the coin toss is interpreted as a classical event described by objective chance or as a quantum event described by many-worlds branching.) the question at the heart of the paradox is what probability sleeping beauty should assign to ‘heads’ when she wakes up at t . the dominant (‘thirder’) view is that the answer is / (elga ); the minority (‘halfer’) view is that the answer is / (lewis ). suppose we impose the treatment of probability required for the tenability of the many- worlds interpretation on the full sleeping beauty paradox. recall that the treatment of probability here is as if each branch has an objective chance of / of occurring. in the sleeping beauty case, this means we can treat the situation as if sleeping beauty is told that when the coin comes up tails, she will be woken up either on monday or on tuesday, with equal (objective) probabilities. that is, we can treat the situation as if there are two coins tosses, where sleeping beauty will be woken up on monday (but not tuesday) if the first coin come up heads, on monday (but not tuesday) if the first comes up tails and the second comes up heads, and on evidence for the widespread acceptance of the thirder solution can be found in white ( ). tuesday (but not monday) if both come up tails. but if this is the right way to analyze the situation, then the paradox dissolves, and the halfer solution is clearly correct. after all, the motivation for the thirder solution is sleeping beauty’s rational expectation at t that she will be woken up twice as often if the (initial) coin-toss comes up tails as if it comes up heads. but on the current understanding of sleeping beauty’s rational expectations, there is no such asymmetry; whatever the result of the (initial) coin-toss, she expects to be woken up once, although if the result is tails then she is uncertain as to which day she will see. this analysis is straightforwardly applicable if the account of probability in the many- worlds interpretation involves genuine pre-branching uncertainty (as saunders ( ) and wallace ( ) maintain). given such uncertainty, sleeping beauty should treat equal-amplitude branching just like a classical coin-toss, and hence she should view her situation as just like the case of two consecutive coin-tosses just described. put another way, if sleeping beauty is genuinely uncertain at t about whether, given that the (initial) coin-toss comes up tails, she will be woken up on monday or on tuesday, then her epistemic situation doesn’t change between t and t . all that changes is her point of view; at t , she is uncertain whether, given that the coin came up tails, she is currently awake on monday or on tuesday. but without a change in epistemic situation, there is no occasion for her to change the probability assigned to ‘heads’ between t and t , and at t that probability is clearly / . but even if the account of probability in the many-worlds interpretation does not involve pre-branching uncertainty, all authors agree that the account must underwrite behavior exactly as if there was genuine uncertainty, in order for it to count as an account of probability (greaves , ; papineau , ; vaidman a). but in that case, sleeping beauty must behave exactly as if she is uncertain whether, given that the coin comes up tails, she will be woken up on monday or on tuesday. and part of behaving that way, as has just been argued, is being willing to bet on ‘heads’ at even odds at t . hence if the treatment of probability by the advocates of the many-worlds interpretation is correct, in any of its forms, then the dominant thirder solution to the sleeping beauty paradox must be rejected in favor of the halfer solution. the argument here assumes that there is no disanalogy between the many-worlds case and the sleeping beauty case that could justify different treatment of probabilities. but this might be challenged. for example, in the many-worlds case, the probabilities are related to the amplitude of the branch via the born rule, and there is nothing analogous to branch amplitude in the sleeping beauty case. but note that this disanalogy is unrelated to the question of whether the relevant probabilities can be assigned prior to the branching event, which is the question at issue here. if there are further disanalogies between the two cases, the argument needs to be made. otherwise, the parallels between the cases constrain your options: if you are a thirder, you must reject the many-worlds interpretation, and conversely, if you accept the many-worlds interpretation you must be a halfer. references elga, adam ( ), “self-locating belief and the sleeping beauty problem”, analysis : – . everett, hugh iii ( ), “‘relative state’ formulation of quantum mechanics”, reviews of modern physics : – . note that this is at odds with the conclusion of vaidman ( b), who maintains that the account of probability required for the many-worlds interpretation entails the thirder solution. greaves, hilary ( ), “understanding deutsch’s probability in a deterministic multiverse”, studies in history and philosophy of modern physics : – . ismael, jenann ( ), “how to combine chance and determinism: thinking about the future in an everett universe”, philosophy of science : – . lewis, david ( ), “sleeping beauty: reply to elga”, analysis : – . papineau, david ( ), “many minds are no worse than one”, british journal for the philosophy of science : – . ——— ( ), “david lewis and schrödinger’s cat”, australasian journal of philosophy : – . saunders, simon ( ), “time, quantum mechanics and probability”, synthese : – . vaidman, lev ( a), “many-worlds interpretation of quantum mechanics”, in edward zalta (ed.), the stanford encyclopedia of philosophy. http://plato.stanford.edu/archives/sum /entries/qm-manyworlds/. ——— ( b), “probability and the many worlds interpretation of quantum mechanics” in a. khrennikov (ed.), quantum theory: reconsideration of foundations. växjö, sweden: växjö university press, – . wallace, david ( a), “worlds in the everett interpretation”, studies in history and philosophy of modern physics : – . ——— ( ), “epistemology quantized: circumstances in which we should come to believe in the everett interpretation”, http://philsci-archive.pitt.edu/archive/ /. forthcoming in british journal for the philosophy of science. white, roger ( ), “the generalized sleeping beauty problem: a challenge for thirders”, analysis, forthcoming. the beauty of character education on preschool children's parent-child relationship procedia - social and behavioral sciences ( ) – available online at www.sciencedirect.com sciencedirect - © published by elsevier ltd. this is an open access article under the cc by-nc-nd license (http://creativecommons.org/licenses/by-nc-nd/ . /). peer-review under responsibility of the organizing committee of cy-icer . doi: . /j.sbspro. . . cy-icer the beauty of character education on preschool children’s parent-child relationship chou, mei-ju, yang, chen-hsin, huang, pin-chen * early childhood education, taiwan shoufu university,taiwan emba postgraduate student of i-shou university, taiwan principal of vincent & kelly preschool, taiwan abstract early childhood education in taiwan puts high value in cultivating young children’s character education, especially for preschool curriculum guideline proposes that character education should starts as earlier as possible. research focus on the importance of character education from early childhood education perspective; however, little study investigated the key factors of character education integrated into parent-child relationship, especially in multi-culture family. this study aims to explore the beauty of character education and its impact on young children’s parent-child relationship. the purposive sampling of the research includes the young children’s parents in the ten preschools adopting the program of character education integrated into family daily life for more than one year in the southern taiwan cities. parents, early childhood education experts and teachers are interviewed and the questionnaire survey is further preceded. the study concludes that in terms of the influencing factors of character education integrated into parent-child relationship, the experts pay attention to children’s character cultivation within the evaluation dimensions in the second hierarchy, with the weight . about . % of the overall weight. the following emphases are parent-child relationship and then parents demography. from the investigation, children’s character cultivation is regarded as the most stressed dimension for character education integrated into preschool children’s parent-child relationship in taiwan. and with the conclusion that character education can deepen the bond between parents and children, as well as significant influence the preschool children’s character cultivation, and also, the preschool parents’ support and scaffolding in children’s storytelling, play, music and arts serve as significant factors in preschool children’s parent-child relationship. © the authors. published by elsevier ltd. peer-review under responsibility of the organizing committee of cy-icer . keywords: character education, preschool, parent-child relationship * corresponding author yang, chen-hsin. tel.: + e-mail address: vincent @gmail.com © published by elsevier ltd. this is an open access article under the cc by-nc-nd license (http://creativecommons.org/licenses/by-nc-nd/ . /). peer-review under responsibility of the organizing committee of cy-icer . http://crossmark.crossref.org/dialog/?doi= . /j.sbspro. . . &domain=pdf http://crossmark.crossref.org/dialog/?doi= . /j.sbspro. . . &domain=pdf chou mei-ju et al. / procedia - social and behavioral sciences ( ) – introducation under the premise of preschool education and care and curriculum guideline implement in taiwan (education bureau, ; ), there are six areas for preschool teachers to cultivate the character education practice for the young children, including language, cognition, social, emotional, physical health, and aesthetics. with the prevalence of parents’ believing in children’s learning outcome are assumed to be more important than their character education cultivation, parents put all efforts in pushing young children learn all kinds of school curriculum even after school time. with the research emphasis on the importance of parent-child interrelationship (cillessen & mayeus, ; elicker et al, ; lafreniere & sroufe, ; parker, rubin, price & derosier, ; stephens, ) and with the importance of value education, moral education proposed by piaget’s research (rheta, ) on children’s reasoning about moral rules, such as telling the truth. the further thinking into the topic is the distinction between two types of morality offering the framework for thinking about early childhood education. parallel to the two types of morality are two types of adult-child relationships (althof & berkowitz, ; howard, berkowitz & schaeffer, ). hence, the study aims to fill the gap between preschool children’s family character education practice and parent-child relationship. for the diverse culture derived from family members in modern times, the awareness, the understanding, and the appreciation of multi-culture, self-reflection, respect issues in modern family would also be included in this study. to conclude, the research aims to explore the beauty of the influencing indicators of family character education integrated into preschool children s parent-child relationship. .literature review and discussion . character education integrated into family early childhood education educators have long concerned themselves with character, morality and values (kohlberg, ; kohn, ), since preschool period plays very significant role in children’s development and learning. jenna ( ) proposed that with the preschool educators’ and parents’ emphasis on honesty, compassion, loyalty, respect, trust, responsibility…etc, our society might not be suffering from severe social and moral problems which are visibly reflected by our young children. for young children, those important revelations on values must be taught, learned, practiced and experienced through interactive environment. following this thoughts, the family parents and the preschool educators are at the forefront in guiding our children to know, to care about and to act upon core ethical values in their daily life experiences. in taiwan’s education system, the long term process of educating young children to develop good character could be traced from confucianism (lockwood, ; white & warfa, ). it is also the blending of moral/character education learning activities into family education to have children acquire, organize, demonstrate, and communicate information (berkowitz & vier, ; althof & berkowitz, ; ginsberg, ). in accordance with john locke, john stuart mill, and herbert spencer, character education is the objective of schooling and family caring (chingos & peterson, ; kessler, ; park& peterson, ). for preschool children, parents create the environment where children can learn, celebrate, and enforce the values on which good character is based. there are a variety of teaching and approaches for us to guide our children in knowing character education, and althof & berkowitz ( ) proposed that newer approaches purport to incorporate children’s thoughts and feelings as suggested in their action expressing, learning, and appreciating. it is very important that parents need to be all concerned that children’s moral reasoning by listening to children’s perspectives, drawing them out, and elevating them in order to promote children’s character development. with the character education of early childhood area, it deals with many dimensions, including honesty, compassion, loyalty, respect, trust, responsibility. those dimensions could also be put into practice through parents scaffolding, assisting, and instructing through children’s daily life experience in play, music stories, visual aids, and pictures. (knight & lagasse, ; martin, ). to put it in more deliberate definition, the activities related to play, music stories, visual aids, and pictures in parent-child relationship are concerned to be in the topic of the research. some research suggested that the application of children’s stories might help elevate young children’s problem-solving skills and the provision of information literacy cultivation (chien & liu, ; deroche & william, ; lai, ). dwyer ( ) indicated that information technology allowed students constructing and inspecting the true situations and learners self-adjusting and applying various resources. kamii and devries ( ) proposed that adults can apply constructivist evaluation to enhance young children’s learning. vygotsky ( ; ) proposed that play and its role in the mental development of the child is so important that early childhood chou mei-ju et al. / procedia - social and behavioral sciences ( ) – educators need to design dynamic assessment to record children’s creativity and imagination. domestic researchers have also emphasized the research on music, plays, and stories integrated into family could enhance parent-child interrelationship. for parent-child interaction in family, stories, music and play of character education presents better applications of interaction, reproducibility, computability, and instrumentalization (andang’o, & mugo, ). moreover, chang ( ) pointed out that parents could have better opportunities in applying character education integrated into family education, especially in cooperation with children’s favorite play, music and stories, the spirit of “active exploration and research” to further cultivate aesthetic apprehension, expression, and creation ability (marilyn, ), and their “independent thinking and problem-solving ability”(lickona, ; bulach, ) could also serve as quality determinants in parent-child interactions. . parent-child relationship for preschool children in the early stages of children’s learning and development, parent-child relationship did lead to children’s future development. young children’s experiences in interacting with parents form the stereotype in their future verbal and physical communication with peers (cillessen & mayeus, ; donovan, stoyles, & berry, ; stephens et al, ). as lafreniere & sroufe ( ) and elicker et al.( ) proposed that the characteristics of children in secure parent-child relationships are desirable to peers. cillessen & mayeus, ( ) suggested that being kind, trustworthy, cooperative, and sociable are common characteristics of peer-accepted children. in accordance with jenna ( ), parker, rubin, price, & derosier, ( ) and stephens et al ( ), these characteristics bring children’s future qualities including curiosity, enthusiasm, positive affect advanced cognitive development. in preschool situation, some of the children are well-liked among their peers, but some of them are not usually recognized as members of the popular group. a significant factor to consider is a positive relationship between parent-child relationship from jenna ( ) include quality, relatedness, autonomy, and idealization. jenna ( ) gave those factors the following definitions adopted by this research: autonomy, generally, is understood as self- governance, and healthy parent-child relationships involve early support and sensitivity of dependency and autonomous functioning; relatedness is a kind of feeling of being connected with others, and positive relatedness with parents creates children a feeling of safety in interacting with the exploration in peers and in environments; the habit of dependent on parents for the dependency on peers in preschool has related effects on the idealization of parents, and idealization is derived from autonomy of parents and individuals; the strong link can be easily found between the type of parent-child relationship quality and children’s later peer relations with relationally aggressive behaviors. and those factors are just the determinants preschool parents can guide children learn from family character education. .research design and method . delphi method delphi method combines the advantage of expert group opinions so as to avoid the situational pressure resulted from face-to-face discussions. the overall opinions and the predicted problems are further feedback to the experts for more opinions. the experts would modify the original opinions according to the overall opinions, and then they would be summarized. by repeating such steps for several times, more consistent prediction would be acquired. having modified delphi method as the research method, present indicators were organized from relevant literatures, and anonymous expert group decision-making was applied to integrating the expert opinions on character education integrated into family. statistical analysis, mean, and quartile deviation were further utilized for systematically processing data in order to acquire the common consensus of the experts on the factors in character education integrated into family. . evaluation indicator the first questionnaire, which was based on the interview from early childhood education professionals, preschool teachers, and preschool children’s parents, titled the considered factors in character education integrated into family, was sent to the experts by email. the considerations for character education integrated into family were organized from the first expert feedback. such considerations were further classified and sent back to the experts for opinions. email was utilized in the process till the final results. an expert conference was eventually held to classify the critical factors in character education integrated into family into the dimensions of parents demography, children’s character cultivation, parent-child relationship. such key factors were further regarded chou mei-ju et al. / procedia - social and behavioral sciences ( ) – as the dimensions for ahp questionnaire. the professionals, the young children’s parents and teachers in the ten preschools in southern taiwan cities were selected as the purposive samples for questionnaire survey. it tended to understand the effects of the weight of each factor on character education integrated into family. with the modification of delphi method, the following evaluation indicators were contained. parents’ demography: .parents’ education degree, . parenting style, .family recreation activity .parents’ moral value . parents’ occupation, and . parents’ monthly income. children’s character cultivation: .children’s stories, .children’s play, .children’s music, and . children’s arts. parent-child relationship: . quality, . relatedness, . autonomy, and idealization. . research subject by distributing the questionnaire to the professionals, teachers, and parents in the preschools in the southern taiwan cities, it was expected to realize the effects of the weight of each factor on character education integrated into family. total copies for preschool parents in kaohsiung were distributed, and total valid ones were retrieved, with the retrieval rate . .discussion of questionnaire data analysis after completing all hierarchical weights, the evaluation indicators were allocated in each hierarchy according to the importance, presenting the importance of the indicator in the entire evaluation system, and the overall weight of the critical indicators in character education integrated into family was selected, table . table : overall weight of the critical factor in character education integrated into family dimension hierarchy ii weight hierarchy ii order indicator hierarchy iii weight hierarchy iii order overall weight overall order parents demography . parents’ education degree . . parenting style . . family recreation activity . . parents’ moral value . . parents’ occupation . . parents’ income . . children’s character cultivation . children’s storybooks . . children’s play . . children’s music . . children’s arts . . parent-child relationship . quality . . relatedness . . autonomy . . idealization . . based on the analyses of questionnaire survey, table , the following conclusions are summarized. within the dimensions in hierarchy ii, the experts focus on children’s character cultivation, with the weight . about . % of the overall weight, followed by parent-child relationship (weight . ) and parents demography (weight . ). the results reveal that children’s character cultivation is the most emphasis for character education integrated into family. within the evaluation indicators in hierarchy iii, the hierarchical weights are ordered as below. i. the evaluation indicators for parents demography are ordered as parents moral value, parenting style, chou mei-ju et al. / procedia - social and behavioral sciences ( ) – family recreation activity, parents income, parents occupation, and parents’ education degree. ii. the evaluation indicators for children’s character cultivation are ordered children’s storybooks, children’s play, children’s music, and children’s arts. iii. the evaluation indicators for parent-child relationship are ordered quality, autonomy , relatedness, and idealization. concerning the professional, teachers and parents’ interview data for constructing the first questionnaire, the summarized description are as follows. in parents demography, to provide sufficient parenting education within family education needs to be assisted by preschool professionals and educators. with a view to making parents feel comfortable both with the resources application through school and community, the child-centered program which children can make choices by themselves is valued importantly as storybooks and play quality time in the family learning environment. however, in assessing children’s character cultivation, teachers and parents need to pay more efforts in taking advantage of children’s music and art activity toward the quality character education in family time. in parent-child relationship, quality is most valued; that is to say, the accumulated time to be with preschool children means less than the quality to be with them. modern parents are always occupied with busy work and life pressure, in addition to arrange family recreation with educational function, the character education could be multiple applying with storybooks, plays, music and arts activity. parents care about the cultivation preschool’s developmental ability in quality, autonomy, relatedness and idealization. only when the interrelationship with parents reaches quality, preschool children would be able to build quality interrelationship with outside world and peers. the materials appealing to preschool children, including stories and play, could also be combined with school and family resources. .conclusion and suggestion research (chingos & peterson ; jacques, ; janis, ; marilyn, ; vicki, ) on the importance of character education for children; with the children’s learning environment lies in preschool and family; therefore, the results of the determinants preschool parents care about show that the application of storybooks and plays could be on the same pace with preschool curriculum activities. what preschool parents secondly value is parents moral/character value; therefore, the preschool could hold regular parenting conference or workshop for parents and community members. with the cooperation of teachers, parents, and community resources, the quality parent-child relationship will be built naturally. take the children’s storybooks for example, there are so many libraries in the community, with the co-experiment activities between libraries and family, parents would have more possibilities to get more assistance in getting appropriate resources in educating children’s character education. further, with the theoretical emphasis on character education, parents could put those theory into practice and preschool children would learn hands-on experience through their real interaction with parents and peers. at last, based on the above analyses, within parent-child relationship, the top five indicators, within the fourteen evaluation indicators, contain ( ) children’s storybooks ( ) parents’ moral value, ( ) children’s play, ( ) quality, and ( ) autonomy; it is assumed that the time parents and children experiment together is very important; therefore, the parents’ perspective in cultivating preschool children in character education needs to be naturally combine with preschool children’s daily life, and the storybooks and free play time would be a very impressive and convenient tool. moreover, with parent’s character value, it is different from each other; therefore, preschool educators can arrange more time in communicating or in exchanging opinions with parents. the fourth one is quality between parent and child relationship; the definition of quality needs to be child-centered. the fifth one is autonomy, which is highly valued by modern times, as we see that many parents and grandmothers are apt to offer too much assistance for children, and it is easy to decrease preschool children’s autonomy in caring, exploring, realizing, reflecting, appreciating, and respecting themselves. finally, parents need to realize that preschool children’s play and learn are highly interrelate in their daily life, no matter in preschool or at home. at last, considering the character education integrated into family toward elevating parent-child relationship, the study propose that parents should spend more time and efforts to understand each child’s inner potential, and with appropriate environment setting up and daily life materials, children’s interrelationship with parents would be elevated through the application of character education into family environment. chou mei-ju et al. / procedia - social and behavioral sciences ( ) – references armstrong, t. 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( ). integrated arts curriculum in hong kong schools. arts education policy review, ( ), - . _ _ _ _ -web .. small is beautiful: why profundaplasty should not be forgotten h. savolainen Æ a. hansen Æ n. diehm Æ i. baumgartner Æ f. dick Æ g. heller Æ b. gahl Æ j. schmidli published online: july � société internationale de chirurgie abstract background surgical profundaplasty (sp)is used mainly as an adjunct to endovascular management of peripheral vascular disease (pad) today. results from earlier series of profundaplasty alone have been controversial, especially regarding its hemodynamic effect. the question is: can profundaplasty alone still be useful? our aim was to evaluate its role in the modern management of vascular patients. methods this was a retrospective outcome study. a consecutive series of patients ( legs) from january through december were included. in ( %) legs, the superficial femoral artery was occluded. these patients were included in the current analysis. of these patients ( %) were female. mean age was (( ) years. nineteen ( %) were diabetic. the indication for operation was claudication in ( %), critical leg ischemia (cli) in ( %), either with rest pain in ( %), or ulcer/gangrene in ( %). endarterectomy with patch angioplasty with bovine pericardium was performed in all cases. mean follow-up was ( months. mean preoperative ankle brachial index (abi) was . . sustained clinical efficacy was defined as upward shift of or greater on the rutherford scale without repeat target limb revas- cularization (tlr) or amputation. mortality, morbidity, need for tlr, or amputation were separate endpoints. results postoperatively, abi was significantly improved (mean = . ), in ( %) by more than . . at three years, cumulative clinical success rate was %. overall, patients with claudication had a better outcome than those with cli (p = . ). two ( %) major amputations and ( %) minor ones were performed, all in patients with cli. none of the ( %) ulcers healed. conclusion profundaplasty is still a valuable option for patients with femoral pad and claudication without tissue loss. it is a straightforward procedure that combines good efficacy with low complication rates. further endovascular treatment may be facilitated. it is not useful for patients with the combination of critical ischemia and tissue loss. since the introduction of distal surgical revascularization and later catheter-based management, surgical profun- daplasty is not commonly performed anymore. results from earlier clinical series have been controversial. in a recent review, earnshaw [ ] concluded: ‘‘there is little literature and no science to provide clear recommendations for profunda disease. indeed, the transatlantic inter- society consensus has nothing to say on the subject.’’ calcified femoral arterial bifurcation is not readily acces- sible for the interventionalist either. a profundaplasty is a straightforward procedure with low morbidity and short hospital stay. does it have any role at all in vascular sur- gery, or should it simply become part of medical history? the aim of our study was to clarify the outcome following open surgical profundaplasty in modern practice. methods between january and december , profun- daplasties were performed in patients at the swiss cardiovascular center (scvc) in berne, switzerland. of the patients, ( %) were female. mean age was h. savolainen (&) � a. hansen � n. diehm � i. baumgartner � f. dick � g. heller � b. gahl � j. schmidli swiss cardiovascular center, university hospital, berne, switzerland e-mail: hannu.savolainen@insel.ch world j surg ( ) : – doi . /s - - -y (± ) years.the superficial femoral artery (sfa) was oc- cluded in ( %) cases. these patients were included in the study. patient charts were retrospectively reviewed. patient characteristics are seen in table . indication for operation was lifestyle-limiting claudica- tion in ( %) and cli in ( %) patients, of which ( %) had ulcer or tissue loss. preoperative duplex scan and angiography were obtained. mean preoperative abi was . . patient selection criteria included ( ) severe stenosis of femoral bifurcation, especially of common and proximal profunda femoris artery with occlusion of the superficial femoral artery, ( ) adequate proximal inflow or inflow to be improved by pta/stenting, and ( ) collaterals seen in angiography. tibial runoff was not an exclusion criteria. the operations were performed as primary surgical reconstruction. previous pta and/or stenting had been performed times in ( %) patients (iliac artery , common femoral , superficial femoral , profunda fem- oris , popliteal times). profundaplasty was performed as previously described by martin et al. [ ]. arterial closure was done using bovine pericardial patch (vascu-guard, synovis life technologies inc., st paul, mn) in all cases. mean (±sd) follow-up was (± . ) months. sustained clinical treatment efficacy was defined as an upward shift of one or more on the rutherford scale [ ] without repeat target limb revascularization (tlr) or amputation. mor- tality, need of amputation, or repeat tlr were solitary study endpoints. cumulative freedom from surgical rein- tervention was defined as freedom from minor or major amputation or arterial reconstruction. subgroup analysis was performed for fontaine stages, for isolated (ip) or combined (ip with pta or stenting) procedure, and dia- betes mellitus. ankle brachial pressure index (abpi) was measured at baseline and postoperatively at intervals. all patients were followed up in the department of angiology at the scvc. statistical analysis statistical analysis was performed using spss software (spss inc., chicago, il). preoperative factors predicting successful outcome were analyzed using fischer’s exact test. kaplan–meier survival analysis was used to estimate the rates of cumulative freedom from surgical reinterven- tion and sustained clinical treatment efficacy. statistical significance of observed differences were evaluated by the log-rank test. wilcoxon signed-rank test was used to compare abpi before and after revascularization. results patients were followed at the swiss cardiovascular centre at three and six months and then annually by clinical examination, abpi measurement, and duplex scan to en- sure the patency of the profunda femoris artery. there was no -day mortality in the group of claudicants, but two patients ( %) with extreme critical ischemia died postoperatively from myocardial infarction. perioperative complications are seen in table . minor surgical com- plications occurred in five ( %) cases: one ( %) superficial infection and three ( %) postoperative hematomas were surgically evacuated under local anesthesia. one ( %) developed postoperative pneumonia. mean postoperative abpi was . . in ( %) patients; it improved signifi- cantly (> . ) after profundaplasty. the difference in pre- versus postoperative abpi was less than . . sustained clinical treatment efficacy according to rutherford [ ] was % at three years (fig. ). in five ( %) legs, a femoropopliteal reconstruction was performed during follow-up ( in claudicants, for critical limb ischemia). in five ( %) legs, an occlusion of sfa was postoperatively treated by pta at an average of five months after the initial procedure. two ( %) iliac arteries were stented to improve inflow. tlrs included two ( %) ptas of the distal profunda. the overall tlr rate was ( %), with some arteries undergoing more than one pta. cumulative freedom from surgical reintervention was % at three years. there was a difference between clau- table patient characteristics age (mean, yr) ± female ( %) male ( %) fontaine ii ( %) fontaine iii ( %) fontaine iv ( %) smoking ( %) diabetes mellitus ( %) renal insufficiency ( %) obesity ( %) dyslipidemia ( %) hypertension ( %) copd ( %) copd = chronic obstructive pulmonary disease, renal insuffi- ciency = creatinine > mg/ml, dyslipidemia = under treatment with statins, obesity = body mass index > kg/m table perioperative morbidity hematoma ( %) wound infection ( %) myocardial infarction ( %) pneumonia ( %) world j surg ( ) : – dicants ( , %) and patients with cli ( , %). clinically, subgroup analysis showed an upward shift in the ruther- ford classification in claudicants versus cli. healing of ischemic lesions was not seen in any of the nine ( %) legs. in the remaining ones, two ( %) major and two ( %) minor amputations were performed. discussion profundaplasty alone is not commonly performed anymore. it has been replaced by vascular reconstructions and cath- eter-based interventions. the inevitable question today is: does surgical profundaplasty have any role in the modern management of peripheral vascular disease? the surgical importance of the profunda femoris artery was discussed by morris et al. [ ] and leeds et al. [ ] in the early s. the revascularization of the deep femoral artery to treat peripheral arterial occlusive disease was introduced by natali in [ ]. cotton and roberts [ ] popularized the deep extended profundaplasty in the s. martin and bouhoutsos [ ] favored a patch over a short length. the first series was published by martin and bouhoutsos [ ], but it dealt mainly with proximal inflow procedures. jamieson [ ] declared that profundaplasty should be used to treat only critical ischemia and was not indicated when the superficial femoral artery is patent. in our unit, we knowingly apply it to patients with claudica- tion, thinking of it rather as part of general management than as a last resort prior to amputation. in our unit, pro- fundaplasty is performed in patients with a patent superfi- cial femoral artery ( %) and in patients with an occluded superficial femoral artery ( %). it has been compared to femoropopliteal reconstructions as well [ ]. to clarify the effect of profundaplasty alone, we excluded patients with a patent sfa from the analysis. many opponents of profundaplasty think it has a very limited hemodynamic effect [ – ]. however, in our study there was a significant postoperative increase in abi (mean = . – . ). of the patients, % had an improvement of greater than . compared with their preoperative values. clinical improvement after profundaplasty has been reported [ – ], but generally the results have been controversial: rollins et al. [ ] reported healing of ulcers in % in a small series. cotton and roberts [ ] reported success in %, treating patients with severe claudica- tion, rest pain, and ulcers. fugger et al. [ ] reported improvement in % in fontaine stage iii ischemia and % in iv. amputations could not be avoided. our group has compared the results of surgical profundaplasty to those of pta [ ]. in our study profunda revascularization was not sufficient in fontaine class iv ischemia (healing in none of the of cases), but it was beneficial in patients with rest pain. in our series, nine ( %) ptas were performed within one year of the operation. interestingly, five ( %) of our patients had a pta of their sfa, probably due to the introduction of modern advanced guidewires that started appearing during the study period. in this situation the patch may well facilitate access for the intervention. in our series, bovine pericardial patch was used in all cases, leaving the vein intact for further options. one ( %) superficial infection was seen. miksic and novak [ ] re- ported impaired results in connection with pta/stenting of the iliac artery. in our series, pta/stenting of the iliac artery was performed in % to improve inflow. in our series, profundaplasty showed a cumulative rate of freedom from any surgical revascularization in % at three years, which can be compared to the results of sutter et al. [ ], who showed a % rate at five years in patients with fontaine stage ii. sustained clinical treatment efficacy was % at three years, which compares favorably with the results of jamil et al. [ ], who found a % success rate in a mixed series of patients. patients with critical ischemia may benefit from pro- fundaplasty as well. however, in the nine patients with cli and tissue loss, none of the ulcers healed. conceivably, all amputations were performed in this group. similar results have been reported by miksic and novak [ ]. cli with time in months . . . . . . survival censored fig. kaplan–meier analysis for sustained clinical efficacy accord- ing to rutherford et al. [ ] world j surg ( ) : – tissue loss can be seen as an indication for femoropoliteal reconstruction, as reported by martin and bouhoutsos [ ]. remote superficial artery endarterectomy and distal stenting have been reported by rosenthal et al. [ ] with a primary patency rate of % at months. the procedure includes femoral endarterectomy if needed. we have no experience with the technique described by moll et al. [ ], but obviously it is technically more demanding than pro- fundaplasty alone. in our study, a short hospital stay and a low rate of complications (no mortality or major morbidity in patients with claudication) were seen. amputations and mortality were restricted to patients with catastrophic critical ische- mia without any possibility of surgical revascularization. as such, profundaplasty does not mean difficulties in case vascular reconstruction is later needed, and the vein is left intact. the bovine pericardial patch is easy to access sur- gically, and it can readily be punctured for endovascular interventions. limitations of our study include its retrospective nature and its relatively small number of patients. however, our follow-up coverage was good and the results present proof of concept for the procedure. in conclusion, profundaplasty, either alone or combined with proximal or distal endovascular intervention, can be used in selected patients suffering from claudication or critical ischemia. it brings good relief of symptoms and objectively improves distal circulation. the operation is straightforward and can be performed with short hospital- ization and low complication rates. profundaplasty is use- ful in critical ischemia with rest pain, but it should not be performed in patients with ischemic tissue loss. references . earnshaw j ( ) surgical options for treatment of profunda stenosis. in: greenhalgh rm (ed) towards vascular and endo- vascular consensus. london, biba, pp – . martin p, renwick s, stephenson c ( ) on the surgery of the profunda femoris artery. br j surg : – . rutherford r, baker j, ernst c, et al. ( ) recommended standards for reports dealing with lower extremity ischemia: re- vised version. j vasc surg : – . morris gc, edwards w, cooley d, et al. ( ) surgical importance of the profunda femoris artery. arch surg : – . leeds rh, gilfillan rs ( ) revascularisation of the ischemic limb. arch surg : – . natali j ( ) by-pass using the deep femoral artery (technique and indications) j chir (paris) : – . cotton lt, roberts vc ( ) extended deep femoral angio- plasty an alternative to femoropopliteal bypass. br j surg : – . martin p, bouhoutsos j ( ) the medium term results after profundaplasty. br j surg : – . jamieson c ( ) reconstruction of, and to, the profunda femoris artery. in: greenhalgh rm (ed) vascular surgical techniques: an atlas. london, wb saunders, pp – . meyer e, adar r ( ) comparison of extended deep femoral angioplasty and femoropopliteal bypass graft in severe ischemia of the leg. world j surg : – . fugger r, krethschmer g, schemper m, et al. ( ) the place of profundaplasty in surgical treatmen of superficial femoral ar- tery occlusion. eur j vasc surg : – . jamil z, hobson rw, lynch tg, et al. ( ) revascularization of the profunda femoris artery for limb salvage. am surg : – . van der plas jp, van dijk j, tordoir jh, et al. ( ) isolated profundaplasty in critical limb ischemia – still of any use? eur j vasc surg : – . kalman pg, johnston kw, walker pm ( ) the current role of isolated profundaplasty. cardiovasc surg : – . sutter t, jauch kw, erlewein g, et al. ( ) long-term results of profundaplasties. vasa : – . mccoy dm, sawchuk ap, shuler jj, et al. ( ) the role of isolated profundaplasty for the treatment of rest pain. arch surg : – . rollins dl, towne jb, bernhard vm, et al. ( ) isolated profundaplasty for limb salvage. j vasc surg : – . diehm n, savolainen h, mahler f, et al. ( ) does deep femoral artery revascularization as an isolated procedure play a role in chronic critical limb ischemia? j endovasc ther : – . miksic k, novak b ( ) profunda femoris revascularization in limb salvage. j cardiovasc surg : – . rosenthal d, martin jd, smeets l, et al. ( ) remote super- ficial femoral artery endarterectomy and distal aspire stenting: results of a multinational study at three-year follow-up. j car- diovasc surg (torino) : – . moll f, ho g, joosten p et al ( ) endovascular remote endarterectomy in femoropopliteal long segmental occlusive disease. a new surgical technique illustrated and preliminary results using a ring strip cutter device. j cardiovasc surg (torino) ( suppl ): – world j surg ( ) : – small is beautiful: why profundaplasty should not be forgotten abstract methods statistical analysis results discussion references << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (none) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /perceptual /detectblends true /colorconversionstrategy /srgb /dothumbnails true /embedallfonts true /embedjoboptions true /dscreportinglevel /syntheticboldness . /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize true /opm /parsedsccomments true /parsedsccommentsfordocinfo true /preservecopypage true /preserveepsinfo true /preservehalftoneinfo false /preserveopicomments false /preserveoverprintsettings true /startpage /subsetfonts false /transferfunctioninfo /apply /ucrandbginfo /preserve /useprologue false /colorsettingsfile () /alwaysembed [ true ] /neverembed [ true ] /antialiascolorimages false /downsamplecolorimages true /colorimagedownsampletype /bicubic /colorimageresolution /colorimagedepth - /colorimagedownsamplethreshold . /encodecolorimages true /colorimagefilter /dctencode /autofiltercolorimages false /colorimageautofilterstrategy /jpeg /coloracsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /colorimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg coloracsimagedict << /tilewidth /tileheight /quality >> /jpeg colorimagedict << /tilewidth /tileheight /quality >> /antialiasgrayimages false /downsamplegrayimages true /grayimagedownsampletype /bicubic /grayimageresolution /grayimagedepth - /grayimagedownsamplethreshold . /encodegrayimages true /grayimagefilter /dctencode /autofiltergrayimages true /grayimageautofilterstrategy /jpeg /grayacsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /grayimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg grayacsimagedict << /tilewidth /tileheight /quality >> /jpeg grayimagedict << /tilewidth /tileheight /quality >> /antialiasmonoimages false /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputcondition () /pdfxregistryname (http://www.color.org?) /pdfxtrapped /false /description << /deu /enu >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice microsoft word - chen final.doc chen_final.doc / / : am truth and beauty: a legal translation jim chen* awake! for morning in the bowl of night has flung the stone that puts the stars to flight: and lo! the hunter of the east has caught the sultán’s turret in a noose of light. –edward fitzgerald, the rubÁiyÁt of omar khayyÁm ranslations, according to conventional wisdom, are like lovers. though the most faithful translations may be plain, the most beautiful translations tend to be unfaithful. the opening words of edward fitzgerald’s translation of the rubáiyát of omar khayyám place fitzgerald’s interpretation of the rubáiyát’s seventy-five quatrains among the most beautiful pieces of english verse. how faithful fitzgerald was to the original farsi is, to put it mildly, a different matter: “the moving finger writes; and, having writ, / moves on.” what concerns me here is the question of fidelity in translation in a realm far removed from poetry. law, which is after all a truth-seeking enterprise, is so thoroughly dedicated to the disciplinary and organizational functions of government that it must banish “falsity, irrationality, and seductiveness” —the very traits that make all literature irresistibly beautiful. this essay addresses questions of truth and beauty, of poetry and fidelity, as applied to legal education and ultimately to law. after discussing how law schools can most faithfully translate their teachings to lawyers’ real concerns, i shall ponder how the law itself reconciles its duty to truth with its practitioners’ longing for beauty. * dean and professor of law, university of louisville. i presented a version of this essay to the downtown louisville rotary club on august , . special thanks to heather elaine worland. . omar khayyÁm, the rubÁiyÁt quatrain , reprinted in rubÁiyÁt of omar khayyÁm and six plays of calderon (edward fitzgerald trans., j.m. dent & sons ). . id. at quatrain . . kenji yoshino, the city and the poet, yale l.j. , ( ). cf. jim chen, poetic justice, cardozo l. rev. , - ( ) (applying yoshino’s theory of law and literature to “all deliberate speed,” the remedial formula adopted in brown v. board of education of topeka, u.s. , ( )). t chen_final.doc / / : am university of toledo law review [vol. i. fidelity in translation even among fields in which lawyers work, an admittedly quotidian set of activities relative to poetry, legal education and academic management put a strong premium on fidelity in translation. law schools owe their primary allegiance to those whose tuition dollars, taxes, and donations enable the entire project of legal education. we owe these students, taxpayers, and benefactors some measure of good faith. indeed, it is no exaggeration to state this proposition in ethical terms. law schools, no less than the lawyers they train, owe the profession an obligation to behave ethically. within the realm of teaching and educational administration, that ethical duty requires faithful translation. legal educators should strive to translate their knowledge about law into real-world applications and outcomes. this act of faithful translation is to the legal academy as zealous representation and fiduciary obligation are to the practicing bar. law is an applied discipline, not a pure science. there are divisions of the ideal university that ponder quantum chromodynamics, universal grammar, and number theory. there are other divisions that design new devices, teach spanish to otherwise monolingual anglophones, or develop new encryption algorithms. law schools emphatically belong to the latter category. as in the health sciences, the greatest challenge facing law schools lies in translating the work of law professors, as teachers and as scholars, into real-world results. medical schools aspire to perfect their programs for translational research. there is a legal equivalent to the medical profession’s desire to deliver health care from bench to bedside. law schools succeed to the extent that they train skilled social engineers. the term “social engineering” carries no pejorative connotation. it describes the conscious, purposeful, and ultimately noble project of avoiding, resolving, and mitigating disputes, and of designing institutions to accomplish goals beyond the reach of individuals. social engineering is the work of lawyers and allied professionals trained in law. i shall translate this admittedly florid and abstract thesis into a set of blunt, pragmatic statements about legal education. law schools have a single mission: we train people to become lawyers or to leverage their legal training into gainful . see generally lawrence lessig, fidelity in translation, tex. l. rev. ( ). . see generally murray gell-mann, the quark and the jaguar: adventures in the simple and the complex ( ) (discussing quark behavior). . see generally, e.g., mark c. baker, the atoms of language: the mind’s hidden rules of grammar ( ) (advancing chomsky’s parametric theory of linguistic diversity); noam chomsky, aspects of the theory of syntax ( ) (discussing transformational grammar). . see generally, e.g., h. davenport, the higher arithmetic: an introduction to the theory of numbers ( th ed. ); richard dedekind, essays on the theory of numbers ( d prtg. ). . see generally, e.g., translational and experimental clinical research (daniel p. schuster et al. eds., ). . cf. c.p. snow, the two cultures: and a second look ( d ed. ) (identifying a “third culture” beyond those of science and literature, that of social scientists “concerned with how human beings are living or have lived”). chen_final.doc / / : am winter ] truth and beauty employment in business, government, philanthropy, or education. our students represent our ultimate product; their accomplishments, our greatest pride. law students—who often arrive at school with more ambition and raw generalized intelligence than anything resembling a marketable skill—have every right to expect a material, measurable return on their investment. legal education at the university of louisville remains one of the profession’s greatest bargains. many law students throughout the rest of the united states nevertheless shoulder tuition in the neighborhood of $ , per year and living expenses in communities that are costly precisely because they surround universities. many law students graduate with six-figure debt loads. this is to say nothing of debts from undergraduate education, family formation, and the ordinary business of life. american legal education today faces stiff challenges. a significant portion of each year’s new crop of law school graduates will be fortunate to find employment, if at all, in the neighborhood of $ , per year in salary. the convergence of high tuition and low salaries is a sign that law schools need to deliver more on their promises. mere job-hunting may not pose worries for students at the very best schools or for the very best students at most other schools, and unemployment certainly lies outside the experience of most law professors. but the vast majority of law students pay tuition and forgo at least three years of other opportunities in order to secure jobs that are more rewarding, in intellectual and financial terms, than those they might otherwise have held. employers often report that many law school graduates need three to five years of on-the-job training to become truly effective. in private practice, the turning point is profitability. law schools must be able to guarantee that their newest graduates will represent leverage, not liabilities. the university of louisville strives to prepare its graduates to be ready for work in every conceivable placement setting, immediately upon graduation and bar exam passage, or at least as quickly as possible thereafter. today’s legal academy often seems to wage war against itself. on one hand, genuine reform efforts stress improvements in teaching that are consciously designed to improve law graduates’ skills and marketability. novel approaches to the first year, experiential learning, interdisciplinary education, and capstone courses represent merely some of the ideas that more enterprising schools have begun to explore and implement. the newly announced university of louisville law clinic represents our school’s most significant innovation in recent memory. by the same token, many other law schools are prone to chasing the latest intellectual fads and pouring enormous amounts of money into collateral projects whose connection to the core mission of training lawyers and other legally sophisticated professionals is apparent, if at all, only to the proponents of those projects. law schools often tout these maneuvers in glossy publications aimed not so much at graduates, donors, and prospective employers of our students, but at . see empirical legal studies: bringing methods to our madness, http://www.elsblog.org/ the_empirical_legal_studi/ / /distribution-of.html (last visited nov. , ). . see generally, e.g., roy stuckey et al., best practices for legal education: a vision and a road map ( ); william m. sullivan et al., educating lawyers: preparation for the profession of law ( ). chen_final.doc / / : am university of toledo law review [vol. other law professors. the legal academy can, should, and does blame much of this imprudence on the u.s. news and world report rankings, particularly that survey’s subjective, reputational components. legal educators as a class, however, cannot afford to ignore the realities facing our students or to neglect our duty to address those realities on their behalf. law schools exist not as playgrounds for abstract intellectual pursuits, but as training grounds for future lawyers. as matters stand, law schools have a very hard time accomplishing their core mission. the real cost of solid legal education is very substantial, and there are no obvious places to cut costs. most law schools depend almost entirely on tuition or on some blend of tuition and precarious public support. it is not at all unusual for unrestricted giving to a law school to hover in the neighborhood of one percent of the overall budget. donors can be persuaded to support a wide variety of causes, ranging from physical facilities, scholarships, and faculty chairs to moot courts and clinics. most donors are law school graduates who had to work hard for relatively low pay before achieving the financial security that now enables them to be generous. they will support their alma maters, in some cases with extraordinary passion, precisely to the extent they feel that they were able to translate their law school experiences into real-world success. the message for legal educators is clear. remaining true to the process by which law school graduates transform themselves for good—in both senses of that phrase—represents fidelity in translation. ii. law’s double helix let us now turn to the related but distinct problem of reconciling truth and beauty within the law itself. as a springboard for discussion, i invoke a different source of poetic inspiration: “beauty is truth, truth beauty,”—that is all ye know on earth, and all ye need to know. the concluding couplet in ode on a grecian urn is arguably the most famous passage in john keats’s body of work, perhaps in all of english poetry in the romantic tradition. the possible unity of truth and beauty has proved so seductive that mathematicians and physicists often rely on unverified links between truth, beauty, and symmetry to frame their hypotheses. . john keats, ode on a grecian urn, in a keats selection (norman howlings ed., ). cf. annie dillard, the maytrees ( ) (quoting keats: “who shall say / between man and woman / which is the … [more] delighted?”). . cf. richard feynman, the character of physical law (the modern library ) ( ). you can recognize truth by its beauty and simplicity. it is always easy when you have made a guess, and done two or three little calculations to make sure that it is not obviously wrong, to know that it is right/.… if you cannot see immediately that it is wrong, and it is simpler than it was before, then it is right/…. [t]he inexperienced … make guesses that are very complicated, and it sort of looks as if it is all right, but i know it is not true because the truth always turns out to be simpler than you thought. chen_final.doc / / : am winter ] truth and beauty although keats may have stated the unity of truth and beauty in memorable literary terms, mathematics may be the discipline that relies most heavily on it. often enough, though not invariably, the unity of truth and beauty holds. what is beautiful is true, and in turn, what is true is beautiful. exceptions do arise—the computer-assisted proof of the four-color theorem and andrew wiles’s proof of fermat’s last theorem are salient examples of mathematical proofs that look more like rambling narratives or even telephone directories than odes. nevertheless, philosophers, poets, and physicists wax rhapsodic in lauding the points in intellectual space where truth achieves what bertrand russell called “a beauty cold and austere, like that of sculpture, without any appeal to any part of our weaker nature, without the gorgeous trappings of painting or music, yet sublimely pure, and capable of a stern perfection such as only the greatest art can show.” edna st. vincent millay echoed this sentiment: “euclid alone has looked on beauty bare.” according to the physicist hermann weyl, the best scientific work has “always tried to unite the true with the beautiful.” but when he “had to choose one or the other,” weyl “usually chose the beautiful.” how firmly does keats’s unity—the unity of truth and beauty—hold in law? law, as i averred in the first half of this essay, is an applied rather than a pure science. but the constituent parts of that science are principally literary and secondarily logical. words are the stuff of which law is made; rules and logical relations lay out the structure by which law applies the letter of the law to the spirit of a particular time and place. law does not live by words alone, but by every value given voice through human culture. “tyger! tyger! burning bright”: one of the fundamental projects of literary analysis is to demonstrate “fearful symmetr[ies],” or structural similarities across literary idioms and genres. that project applies with full force in law as in literature. true to the serendipitous way in which law arises, i stumbled unto what i believe to be the best description of keats’s unity in a memoir described as a uniquely powerful first-personal account of science in action. in the opening pages of the double helix: a personal account of the discovery of the structure of dna, james d. watson explained how the quest for beauty and the quirks of human culture bent the trajectory of the quest for the double helix: id. . see neil robertson et al., a new proof of the four-colour theorem, elec. res. announcements am. mathematical soc’y ( ). . see generally andrew john wiles, modular elliptic curves and fermat’s last theorem, annals mathematics ( ). . bertrand russell, the study of mathematics, in mysticism and logic, and other essays ( ). . edna st. vincent millay, euclid alone has looked on beauty bare, in edna st. vincent millay selected poems (j.d. mcclatchy ed., american poets project ). . edward o. wilson, biophilia ( ) (quoting hermann weyl). . william blake, the tyger, in de/compositions: good poems gone wrong (w.d. snodgrass ed., ). . james d. watson, the double helix: a personal account of the discovery of the structure of dna (touchstone books ) ( ). chen_final.doc / / : am university of toledo law review [vol. [s]cience seldom proceeds in the straightforward logical manner imagined by outsiders. instead, its steps forward (and sometimes backward) are often very human events in which personalities and cultural traditions play major roles. to this end i have attempted to re-create my first impressions of the relevant events and personalities rather than present an assessment which takes into account the many facts i have learned since the structure was found. although the latter approach might be more objective, it would fail to convey the spirit of an adventure characterized both by youthful arrogance and by the belief that the truth, once found, would be simple as well as pretty. thus many of the comments may seem one-sided and unfair, but this is often the case in the incomplete and hurried way in which human beings frequently decide to like or dislike a new idea or acquaintance. law proceeds on terms somewhere between the extremes of euclid’s airtight elements and the comprehensive computer-aided proof of the four-color theorem. as francis crick and james watson discovered when they sought to unlock the structure of dna, the quest for the social truth that law embodies may begin in “the belief that the truth, once found, would be simple as well as pretty.” that gesture of “youthful arrogance,” however, rarely, if ever, yields the truth on its own. no less than their scientific counterparts, lawyers follow an “incomplete and hurried” protocol by which they “frequently decide to like or dislike a new idea or acquaintance.” like other outsiders, law students often envision the formation, interpretation, and enforcement of law as a straightforward, even logical process. they soon learn, as oliver wendell holmes observed in the opening lines of the common law, that “[t]he life of the law has not been logic: it has been experience.” even as watson acknowledged how science lurched “forward (and sometimes backward)” in response to “very human events in which personalities and cultural traditions play major roles,” holmes recognized that law does not so much observe syllogisms as reflect “[t]he felt necessities of the time, the prevalent moral and political theories, intuitions of public policy, avowed or unconscious, even the prejudices which judges share with their fellow” citizens. two intertwined strands run through all law. one strand represents the cold mathematical logic that the law school admission test purports to measure, the austere beauty of legal reason deduced without regard to the social circumstances in which law must be made, enforced, and lived. the other strand speaks in historical, even literary or lyrical terms. that manifestation of truth in law, as holmes explained, “embodies the story of a nation’s development through many centuries, . id. at xi-xii. . id. at xi. . id. . id. at xi-xii. . oliver wendell holmes, jr., the common law ( ). . watson, supra note , at xi. . holmes, supra note , at . chen_final.doc / / : am winter ] truth and beauty and it cannot be dealt with as if it contained only the axioms and corollaries of a book of mathematics.” that is all you know in law, and all you need to know. . id. << /ascii encodepages false /allowtransparency false /autopositionepsfiles false /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /warning /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /leavecolorunchanged /dothumbnails false /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize false /opm /parsedsccomments true /parsedsccommentsfordocinfo true /preservecopypage true /preservedicmykvalues true /preserveepsinfo true /preserveflatness true /preservehalftoneinfo true /preserveopicomments false /preserveoverprintsettings true /startpage /subsetfonts true /transferfunctioninfo /remove /ucrandbginfo /remove /useprologue true /colorsettingsfile (color management off) /alwaysembed [ true ] /neverembed [ true ] /antialiascolorimages false /cropcolorimages true /colorimageminresolution /colorimageminresolutionpolicy /ok /downsamplecolorimages false /colorimagedownsampletype /bicubic /colorimageresolution /colorimagedepth /colorimagemindownsampledepth /colorimagedownsamplethreshold . /encodecolorimages true /colorimagefilter /flateencode /autofiltercolorimages false /colorimageautofilterstrategy /jpeg /coloracsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /colorimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg coloracsimagedict << /tilewidth /tileheight /quality >> /jpeg colorimagedict << /tilewidth /tileheight /quality >> /antialiasgrayimages false /cropgrayimages true /grayimageminresolution /grayimageminresolutionpolicy /ok /downsamplegrayimages false /grayimagedownsampletype /bicubic /grayimageresolution /grayimagedepth /grayimagemindownsampledepth /grayimagedownsamplethreshold . /encodegrayimages true /grayimagefilter /flateencode /autofiltergrayimages false /grayimageautofilterstrategy /jpeg /grayacsimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /grayimagedict << /qfactor . /hsamples [ ] /vsamples [ ] >> /jpeg grayacsimagedict << /tilewidth /tileheight /quality >> /jpeg grayimagedict << /tilewidth /tileheight /quality >> /antialiasmonoimages false /cropmonoimages true /monoimageminresolution /monoimageminresolutionpolicy /ok /downsamplemonoimages false /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname (http://www.color.org) /pdfxtrapped /false /description << /jpn /deu /fra /ptb /dan /nld /esp /suo /ita /nor /sve /enu (use these settings to create pdf documents suitable for reliable viewing and printing of business documents. the pdf documents can be opened with acrobat and reader . and later.) >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice spectator effects in inclusive decays of beauty hadrons ukqcd collaboration. massimo di pierro a and chris t. sachrajda b . presented by m.d.p. department of physics and astronomy, university of southampton, so bj, united kingdom amdp@hep.phys.soton.ac.uk bcts@hep.phys.soton.ac.uk we evaluate the matrix elements of the four-quark operators which contribute to the lifetimes of b-mesons and the Λb-baryon. we find that the spectator effects are not responsible for the discrepancy between the theoretical prediction and experimental measurement of the ratio of lifetimes τ(Λb)/τ(b). . introduction inclusive decays of heavy hadrons can be stud- ied in the framework of the heavy quark expan- sion, in which, for example, lifetimes are com- puted as series in inverse powers of the mass of the b-quark [ ]. for an arbitrary hadron h τ− (h) = g fm b π |vcb| mh ∑ i≥ cim −i b ( ) where • c corresponds to the decay of a free-quark and is universal. • c is zero because the operators of dimen- sion four can be eliminated using the equa- tions of motion. • c can be estimated and is found to be small. • c contains a contribution proportional to 〈h| bΓq qΓ̃b |h〉 ( ) and is therefore the first term in the expan- sion to which the interaction between the heavy and the light quark(s) contribute. al- though this is an o(m− b ) correction, it may be significant since it contains a phase-space enhancement. the aim of our lattice simulation is to compute c for b-mesons and the Λb-baryon, in order to check whether spectator effects contribute signif- icantly to the ratios of lifetimes for which the ex- perimental values are: τ(b−) τ(b ) = . ± . ( ) τ(Λb) τ(b ) = . ± . . ( ) the discrepancy between the experimental value in eq. ( ) and the theoretical prediction of τ(Λb)/τ(b ) = . (based on the operator product expansion in eq. ( ) including terms in the sum up to those of o(m− b )) is a major puzzle. it is therefore particularly important to compute the o(m− b ) spectator contributions to this ratio. the ratios in eqs. ( ) and ( ) can be expressed in terms of matrix elements: τ(b−) τ(b ) = a + a ε + a ε + a b + a b ( ) τ(Λb) τ(b ) = b + b ε + b ε + b l + b l ( ) where b ≡ f bmb 〈b| bγµlq qγµlb |b〉 mb ( ) b ≡ f bmb 〈b| blq qrb |b〉 mb ( ) in terms of the parameters b̃ and r introduced in ref. [ ] r = − l b̃ = − l /l − / ε ≡ f bmb 〈b| bγµltaq qγµlt ab |b〉 mb ( ) ε ≡ f bmb 〈b| bltaq qrtab |b〉 mb ( ) l ≡ f bmb 〈Λ| bγµlq qγµlb |Λ〉 mΛ ( ) l ≡ f bmb 〈Λ| bγµltaq qγµlt ab |Λ〉 mΛ ( ) and the coefficients ai and bi are given by value value a + . b + . a − . b − . a + . b + . a + . b + . a + . b − . the values in the table correspond to opera- tors renormalized in a continuum renormalization scheme at the scale µ = mb. their matrix ele- ments are obtained from those in the lattice reg- ularization by perturbative matching (see the ap- pendix). . b decay the matrix elements b ,b ,ε ,ε are com- puted on a × lattice at β = . (correspond- ing to a lattice spacing a− = . ( ) gev) using the tree-level improved sw action for three values of κ = . , . , . and are then ex- trapolated to the chiral limit (κc = . ) [ ]. we find b = . ± . ( ) b = . ± . ( ) ε = − . ± . ( ) ε = − . ± . ( ) which implies that τ(b−) τ(b ) = . ± . ± . ( ) in agreement with the experimental value ( ). . Λ decay the computation the baryonic matrix elements l and l is a little more difficult. we have per- formed an exploratory study in which the light quark propagators are computed using a stochas- tic method [ ] based on the relation m− ij = ∫ [dφ](mjkφk) ∗φie −φ∗i (m +m)ijφj ( ) (rather then using “extended” propagators). the matrix elements are computed on a × lattice at β = . (corresponding to a lattice spacing a− = . ( ) gev) for two values of κ. we therefore do not attempt an extrapolation to the chiral limit (κc = . ) but present results seperately for each value of κ. we find: l = { − . ± . (κ = . ) − . ± . (κ = . ) ( ) l = { . ± . (κ = . ) . ± . (κ = . ) , ( ) which implies that (neglecting the systematic er- ror due to the chiral extrapolation) τ(Λb) τ(b ) = { . ± . (κ = . ) . ± . (κ = . ) . ( ) these results imply that spectator effects are not sufficiently large to explain the discrepancy be- tween the theoretical prediction and experimental result in eq. ( ). . concluding remarks we find that the matrix elements of the -quark operators ( - ) satisfy the vacuum saturation hypothesis remarkably well. a similar feature is true for the ∆b = operators which contribute to b–b̄ mixing. we do not have a good under- standing yet of this phenomenon. the results for the mesonic matrix elements lead to a prediction for the ratio of the lifetimes of the charged and neutral mesons which is in agreement with the experimental result in eq. ( ). our study of the baryonic matrix elements in- dicates that spectator effects are not sufficiently large to explain the experimental ratio of life- times in eq. ( ). this discrepancy between the theoretical prediction and the experimental mea- surement remains an important problem to solve. we do stress, however, that our calculations are table lattice perturbative coefficients and operators pi pi qi qi − log(λ a ) + . bΓqqΓ̃b + bΓqbΓ̃q − log(λ a ) + . btaΓtaqqΓ̃b + bΓqqtaΓ̃tab + btaΓtaqbΓ̃q + bΓqbtaΓ̃taq − . btaγ Γγ taqqΓ̃b + bΓqqtaγ Γ̃γ tab + btaγ Γγ taqbΓ̃q + bΓqbtaγ Γ̃γ taq log(λ a ) − . btaΓqqΓ̃tab − btaΓqbtaΓ̃q log(λ a ) − . bΓtaqqΓ̃tab + btaΓqqtaΓ̃b − bΓtaqbtaΓ̃q + btaΓqbΓ̃taq − . bΓγ taqqΓ̃γ tab + btaγ Γqqtaγ Γ̃b + bΓγ taqbtaγ Γ̃q + btaγ ΓqbΓ̃γ taq − log(λ a ) + . bΓtaqqγ Γ̃b − bΓtaqbΓ̃taq − log(λ a ) + . bΓσµνtaqqtaσνµΓ̃b − bΓσµνtaqbΓ̃σµνtaq − . bΓγµtaqqtaγµΓ̃b + bΓγµtaqbΓ̃γµtaq the analytic expression for pi can be found in [ ]. exploratory, and a more precise simulation is nec- essary, in particular to allow for a reliable extrap- olation to the chiral limit. acknowledgements it is a pleasure to thank chris michael, hart- mut wittig, jonathan flynn, luigi del debbio, giulia de divitiis, vicente gimenez and carlotta pittori for many helpful discussions. this work was supported by pparc grants gr/l , gr/l and gr/i . appendix: -loop lattice perturbative cor- rections to -quark operators the most difficult component of the evaluation of the -loop perturbative matching between four- quark lattice operators and those renormalized in a continuum scheme is the perturbative expan- sion on lattice. in this appendix we present the corresponding results for generic operators p and q (whose matrix elements contribute to lifetimes and b–b̄ mixing respectively): p ≡ bΓq qΓ̃b, (∆b = ) ( ) q ≡ bΓq bΓ̃q, (∆b = ) . ( ) Γ⊗Γ̃ represents an arbitrary spinor and color ten- sor. these operators mix under renormalization with other -quark operators, listed in table : p loop = p + αs(a − ) π ∑ i pipi ( ) q loop = q + αs(a − ) π ∑ i piqiqi . ( ) the feynman rules correspond to the tree-level sw-improved action for massless light quarks and with a small gluon-mass (λ) as the infrared reg- ulator. the dependence on λ, of course, cancels when the corresponding continuum calculation is combined with the lattice one. references . i. bigi, m. shifman and n. uralstev, ann. rev. nucl. part. sci. ( ) and references therein. . m. neubert and c. t. sachrajda, nucl. phys. b ( ) . . m. di pierro and c. t. sachrajda, hep-lat/ (to be published in nucl. phys. b). . c. michael and j. peisa, hep-lat/ . . m. di pierro, c. t. sachrajda and c. michael, in preparation. . v. gimenez and j. reyes, hep-lat/ these results were also obtained independently in ref. [ ]. significantly at one and hours after paracentesis. creatinine clearance fell significantly at hours, and plasma renin activity, an index of intravascular volume, rose after hours. peripheral oedema did not seem in these patients to protect renal function or to prevent a rise in plasma renin activity. these findings agree with those of gines et al, who showed that daily - litre paracentesis without replacement of albumin resulted in deterioration of renal function and a rise in plasma renin activity.' in another recent study tit et al found no deterioration in renal function or rise in plasma renin activity after single total paracentesis with an albumin infusion of g for each litre of ascites removed. most patients in these studies had baseline serum creatinine concentrations of less than i tmol/l and serum sodium concentrations higher than mmol/l. as a group they would be expected to respond well to diuretic and dietary measures. although paracentesis shortened the stay in hospital and reduced costs in the study of quintero et al,` patients treated with dietary measures and diuretics do not have to be detained in hospital until the ascites disappears. once an effective diuretic regimen is established without electrolyte derangement patients may be treated as out- patients. in those with hepatic decompensation or recent alcoholic hepatitis longer stays in hospital may be desirable even after treatment by paracentesis. furthermore, the cost of the albumin replacement must be considered. in our experience the amount of albumin required is g for a paracentesis of litres, at a cost of around £ . we think that patients with near normal renal function (serum creatinine concentration less than !lmol/l) and serum sodium concentrations higher than mmol/l can tolerate large volume paracentesis (up to litres) without replacement of albumin. clinically important haemodynamic decompensation is unlikely, at least immediately after para- centesis.' a fall in creatinine clearance is, however, likely unless albumin is given. - when peripheral oedema is present no untoward effects are seen with a single paracentesis of up to litres without replacement of albumin"; albumin should be given if more than this is removed or if taps are repeated. in patients without peripheral oedema it is safer to give albumin for all large volume ( litres) or repeated paracenteses. paracentesis is certainly needed when gross ascites causes respiratory embarrassment, severe discomfort, or breakdown of the skin. nevertheless, we believe that for most patients with ascites from cirrhosis the judicious use of diuretics remains the best treatment. when paracentesis is performed complete clearance of the ascites by a single paracentesis is preferable to multiple smaller taps. this avoids continued leakage from the para- centesis site and reduces the chance of infection. in all cases paracentesis should be followed by maintenance treat- ment with diuretics or fluid restriction in patients who are hyponatraemic to prevent recurrence of the ascites. renal function and serum electrolyte concentrations should be monitored for at least one week after paracentesis. several important questions about paracentesis remain unanswered. for instance, when renal function deteriorates after paracentesis is the deterioration reversible, and if so how long does it take to recover? does the plasma volume and the renal protective effect of an infusion of albumin persist after hours? further clinical trials are needed to answer these questions and to examine the possible long term benefits of paracentesis compared with treatment with diuretics. marios panos clinical research fellow david westaby consultant physician roger williams director liver unit, king's college hospital and school of medicine and dentistry, london se rs i liebowitz hr. hazards of abdominal paracentesis in the cirrhotic patient. part iii. nystatej med ; : - . summerskill whj, baldus wp. ascites. in: schiff l, ed. diseases ofthe liver. th ed. philadelphia: lippincott, : - . sherlock s, senewiratne b, scott a, walker jg. complications of diuretic therapy in hepatic cirrhosis. lancet ;i: . sherlock s, ed. diseases ofthe liver and biliary svstem. th ed. oxford: blackwell, : - . perez-ayuzo rm, arroyo v, planas r, et al. randomised comparative study of efficacy of frusemide versus spironolactone in non-azotemic cirrhosis with ascites relationship between the diuretic response and the activity of the renin-aldosterone system. gastroenterology ; : - . fogel mr, sawhney vk, neal ea, miller rg, knauer cm, gregory pb. diuresis in the ascitic patient: a randomised controlled trial of three regimens. j clin gastroenterol ; (suppl): - . shear l, ching s, gabuzda gj. compartmentalization of ascites and edema in patients with hepatic cirrhosis. n engl_ med ; : - . epstein m. renal functional abnormalities in cirrhosis; patho-physiology and management. in: zakim d, boyer td, eds. hepatology: a textbook of liver diseases. philadelphia: saunders, : . pockros pj, reynolds tb. rapid diuresis in patients with chronic liver disease: the importance of peripheral oedema. gastroenterology ; : - . quintero e, gines po, arroyo v, et al. paracentesis versus diuretics in the treatment of cirrhotics with tense ascites. lancet ;i: - . kao hw, rakov ne, savage e, reynolds tb. the effect of large volume paracentesis on plasma volume-a cause of hypovolaemia? hepatology ; : - . simon dm, mccain jr, bonkovski hl, wells jo, hartle dk, galambos jj. effects of therapeutic paracentesis on systemic and hepatic hemodynamics and on renal and hormonal function. hepatology ; : - . gines p, tit li, panes j, et al. paracentesis versus paracentesis plus intravenous albumin in the treatment of ascites. preliminary results of a comparative study. hepatol [suppl] ; : . tito li, gines p, panes j, et al. total paracentesis plus intravenous albumin infusion in the treatment of cirrhotics with tense ascites. hepatol [suppl] ; : . small is hard as well as beautiful encouragement rather than growth hormone there is a good chance that in the american election the taller candidate will win: schoolchildren associate taller people with more prestigious occupations.' already year olds have stereotypes based on physical appearance. small people find it hard to build up public reputation and gain respect because social attitudes reflect traditional stereotypes of their low stature. adults find it hard to learn alternative ways to react when faced with an appealing small child. various behaviour patterns such as dependency, lack of aggressiveness and competitiveness, clowning, and social withdrawal have been associated with small stature. these are best seen as strategies for coping, and they reflect both the children's skills and the pressures they experience. specific causes of small stature are associated with differing problems. children with hypopituitarism elicit protective responses as their babyish facial features induce caring. they experience specific learning difficulties, which may be secondary to cognitive deficits. girls with turner's syndrome have poor visuospatial organisation. in children with familial short stature the family response will be affected by the problems experienced by the parents. the children whose difficulties are the most complex to evaluate are those with bmj volume september o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b m j: first p u b lish e d a s . /b m j. . . o n s e p te m b e r . d o w n lo a d e d fro m http://www.bmj.com/ "environmental" growth delay (non-organic failure to thrive). intellectually they often have depressed intelligence quotients and language disorders. their behaviour may be bizarre, and their views of themselves are often extremely poor. there seem to be no specific differences between the behaviour patterns of boys with constitutional delay and growth hormone deficiency. age is the most important factor influencing the children's difficulties. as puberty approaches the importance of stature increases, especially among boys.' the growth spurts of peers emphasise height differences, and peer pressures for group identification may be associated with the exclusion of small children. they become isolated but not through general lack of social skills (except for some girls with turner's syndrome who may have more difficulty in understanding social cues ). at this time small children are most vulnerable, and their academic performance deterio- rates before recovering in later adolescence. greater attention to physical characteristics coupled with greater attention to internal physical states by those who care for them increases the distress. increased self awareness often leads to negative self evaluations. in our response to small children we need to maximise their resources and maintain expectations that are appropriate for age rather than height. the aim is to foster their autonomy and facilitate a sense of their own capabilities. they must be helped to live with their predicament in a positive manner; they must not be allocated the sick role. this means making demands that stretch their capabilities, which are likely to be commensurate with age rather than height. psychological investigations may help clarify specific learning difficulties. small children may be taught ways ofcoping with the social pressures of adolescence as puberty approaches. we need to question the value that society places on size rather than to contemplate using growth hormone more. programmes to reduce bullying suggest that initiatives directed at social processes in schools may create a better climate for the psychological growth of these children. resilience does not lie in avoiding stress but rather in encountering it in a way that allows self confidence and social competence to increase through mastery and appropriate responsibility.' simon r wilkinson consultant, department of child psychiatry, ulleval sykehus, oslo , norway i morrow j. deviational salience; application to short stature and relation to perception of adolescent boys. percept mot skills ; : - . lerner rm, korn sj. the development of body build stereotypes in males. child dev ; : - . dorner s, elton a. short, taught and vulnerable. special education ; : - . skuse d. the psychological consequences of being small. j child psvchol psvchiatry ; : - . holmes cs, hayford jt, thompson rg. personality and behavior differences in groups of boys with short stature. children's health care ; : - . holmes cs, karlsson ja, thompson rg. social and school competencies in children with short stature: longitudinal patterns. j dev behav pediatr ; : - . mechanic d. adolescent health and illness behavior: review of the literature and a new hypothesis for the study of stress. human stress ; : - . olweus d, roland e. mobbing: bakgrunn og tiltak (bullying: background factors and approaches). oslo: kirke-og undervisnings departement, . olwens d. schoolyard bullying-grounds for intervention. school safety fall: - . rutter m. resilience in the face of adversity: protective factors and resistance to psychiatric disorder. br_' psvchiatrv ; : - . vascular disease, thrombosis, and recurrent abortion may be linked by antibodies against phospholipids in the past few years a clinical syndrome has been defined that links venous thrombosis, recurrent abortion, and un- explained cerebral dysfunction and ischaemic episodes." these clinical observations have been associated with antibodies directed against phospholipids. these antibodies seem to accelerate thrombosis in some patients-perhaps by their effects on the phospholipids of platelets or endothelial cell membranes. the risk of thrombosis is strong-indeed, for some patients with high antibody titres the risk ratio is higher than that for smoking. although the antibodies are directed against various phospholipids, the early research selected cardiolipin as the test antigen-largely because reasonably pure cardiolipin was readily available. sensitive and reproducible enzyme linked immunosorbent assays (elisa) currently make testing for cardiolipin antibody cheap and widely available, and the assays have largely replaced older cumbersome "coagulation" tests such as the lupus anticoagulant test. the original observations were made in systemic lupus erythematosus, a disease in which patients have a broad range of antibodies. some patients with atypical systemic lupus erythematosus (who often failed to meet the classification criteria of the american rheumatism association) had recurrent thrombosis and recurrent abortion, and their serum contained phospholipid antibodies often without other autoantibodies. later it became clear that most patients with this syndrome have little or no other evidence of lupus. the anticardiolipin syndrome-or more correctly the phospholipid antibody syndrome-is now reasonably well defined. the classic example of a patient with the syndrome is a young woman with a history of recurrent deep vein thrombosis, sometimes associated with the contraceptive pill or with stopping warfarin who then presents with recurrent spontaneous miscarriages. other thrombotic events may include axillary, ocular, or renal vein thrombosis and the budd-chiari syndrome."'°" several patients with the syndrome develop pulmonary hypertension," possibly because of episodes of pulmonary thrombosis. major arterial thrombosis may also occur, especially recurrent strokes,'" early myocardial ipfarction,' 's and peripheral arterial occlusion. several patients have developed multi-infarct dementia in association with phospholipid antibodies.' pregnant patients with raised titres of phospholipid anti- bodies (including the lupus anticoagulant) suffer a high risk of spontaneous abortion, possibly because of placental vessel thrombosis.' " indeed, some patients have had or more failed pregnancies. other features of the syndrome include livedo reticularis, chorea, ' and thrombocytopenia, and some speculate that the antibodies may be associated with disease of the heart valves, migraine and labile hypertension, and some myelopathies. there is a danger of overinterpreting the results of tests for phospholipid antibodies, especially those that give borderline results. it would not be surprising, for example, to find transient rises of antibody titre after certain infections. for this reason attempts to standardise the tests are important. the reliability of assays will be especially important in epidemiology: the true extent of the anticardiolipin syndrome is unknown, and large studies are in progress in vascular, bmj volume september o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b m j: first p u b lish e d a s . /b m j. . . o n s e p te m b e r . d o w n lo a d e d fro m http://www.bmj.com/ beauty is better pursued: effects of attractiveness in multiple-face tracking journal: quarterly journal of experimental psychology manuscript id: qje-std - .r manuscript type: standard article date submitted by the author: n/a complete list of authors: liu, chang; university of hull, department of psychology chen, wenfeng; institute of psychology, chinese academy of sciences keywords: attractiveness, multiple-face tracking, attention url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology dear professor tipper, thank you for your thoughtful comments. we have now carefully revised our manuscript according to your new suggestions. . following your advice, we have performed separate analyses for male and female participants. this showed significant main effects of attractiveness and face gender for female participants. there was also an interaction between the two variables. however, no effects were found for male participants. the pattern of results is consistent with your prediction. the new analyses have been added to the result section. we have also discussed this gender effect further in general discussion. we agree that if schacht et al ( ) did use fewer females, it could have been a cause for discrepant findings. we have checked this and found that they used female and male participants. perhaps as they suggest, "the effects of attractiveness are strongly task dependent." . we have qualified our general conclusion that attractiveness is automatically computed and high level processes feedback into earlier tracking. we have cautioned that the attractive effects may only be true of female participants because of the findings in experiment (previously experiment ). we have also mentioned the similarity between the gender effect in our study and the effect in bayliss et al. we have qualified the broad statements in the abstract as well. . we agree that more data from male participants for all other experiments would have been ideal. however, due to our limited resources, we have found this to be quite difficult to accomplish. we have therefore followed your second solution to re-write and restructure the paper. we hope the potential sex difference will spark future research. following your instruction, we have highlighted the changes we made in the manuscript by using the track changes mode in ms word. sincerely yours, chang hong liu and wenfeng chen page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking running head: attractiveness affects multiple-face tracking beauty is better pursued: effects of attractiveness in multiple-face tracking chang hong liu university of hull wenfeng chen chinese academy of sciences correspondences: chang hong liu, phd wenfeng chen, phd department of psychology institute of psychology university of hull chinese academy of sciences cottingham road a datun road hull, hu rx chaoyang district, beijing united kingdom china tel: + - tel: + - fax: + - fax: + - email: c.h.liu@hull.ac.uk email: chenwf@psych.ac.cn page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology mailto:chenwf@psych.ac.cn attractiveness affects multiple-face tracking abstract using the multiple-object tracking paradigm, this study examines how spontaneous appraisal for facial beauty affects distributed attention to multiple faces in dynamic displays. observers tracked attractive faces more effectively relative to unattractive faces in this task. tracking performance was only affected by target attractiveness, suggesting an absence of appraisal for distractor attractiveness. attractive male faces also produced stronger binding of face identity and location for female participants. together, the results suggest that facial attractiveness was appraised during tracking even though this was task irrelevant. contrary to the theory that multiple-object tracking is driven by encapsulated low-level vision, our results show that the content of target representation is not only penetrable by social cognition but also modulates the course of tracking operations. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking beauty is better pursued: effects of attractiveness in multiple-face tracking it is well known that human observers pay greater attention to faces than to non-face objects (e.g., ro, russell, & lavie, ). moreover, some face stimuli attract more attention than others. apart from certain facial expressions such as fear and anger (palermo & rhodes, ), attractive faces also trigger greater attention (sui & liu, ). popular culture often suggests that a mere glance of a face elicits spontaneous appraisal of attractiveness. humans may be predisposed to direct attention to attractive faces because of their biological and social significance. there is well-established evidence that even newborn babies look at attractive faces longer (e.g., geldart, maurer, & carney, ; langlois et al., ; samuels et al., ; slater et al., ). adults also tend to spend more time looking at beautiful faces (aharon et al., ; kranz & ishai, ), which are known to activate dopaminergic regions in the brain that are strongly linked to the reward system (kampe, frith, dolan, & frith, ). appraisal of facial beauty appears to depend on how well a face resembles the average in a population (langlois & roggman, ). although symmetry also plays a role in facial beauty (e.g., grammer & thornhill, ), there is evidence that it is less important than averageness (rhodes, sumich, & byatt, ; also see rhodes, , for an extensive review). hence attentional capture by attractive faces may rely on preattentive computation of averageness in face stimuli. however, little is known about how facial attractiveness affects attentional mechanisms. this issue may be addressed through the existing attention paradigms. for example, maner, gailliot, and dewall ( ) employed a dot-probe paradigm to assess the effect of attractiveness on disengaging attention. consistent with their hypothesis, their observers were slower at disengaging attention from attractive female faces relative to average-looking page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking female or male faces. in another study, maner, gailliot, rouby, and miller ( ) used the same method and found that participants fixated on highly attractive faces within the first half second and took longer to stop looking at them when asked to shift their attention away. in a different approach, sui and liu ( ) investigated whether appraisal for attractiveness occurs when spatial attention has already been directed elsewhere. they employed a spatial cuing task, where participants were asked to judge the orientation of a cued target presented to the left or right visual field while ignoring a task-irrelevant face image flashed in the opposite field. they found that the presence of attractive faces significantly lengthened task performance. this suggests that facial beauty can automatically compete with an ongoing task for attention, although this does not necessarily mean that appraisal of facial beauty is a mandatory process (see schacht, werheid, & sommer, ). the analysis of eye movements in sui and liu’s study revealed that the effect of facial attractiveness was not due to foveal fixation on the target or face stimuli, hence there is a strong possibility that facial attractiveness can be detected outside the fovea. this has been confirmed by a recent investigation, where discrimination of facial beauty was measured at several eccentricities (guo, liu, & roebuck, ). both dot-probe and cuing tasks require focused attention, where attention is directed to a single spatial location. however, attention in reality can be distributed to several different targets or spatial locations. for instance, a group activity requires attention to be paid to multiple individuals and locations. the main purpose of this research was to investigate the effect of facial attractiveness on distributed attention. another motivation of this research comes from observation that spontaneous appraisal of attractiveness is rapid and transient (schacht et al., ). it remains unclear whether such an appraisal only manifests in brief attentional shifts. hence the second purpose of this study was to investigate whether a similar kind of automatic appraisal for facial attractiveness occurs continuously when sustained page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking attention is distributed among faces in multiple locations. pylyshyn and storm ( ) designed a multiple-object tracking paradigm (mot) to study how human observers maintain attention on multiple objects across space and time. in recent years, the issue of content addressability in object tracking is hotly debated. this issue was first raised by pylyshyn ( ) who found that observers were remarkably poor at identifying the features or identity of correctly tracked objects. this phenomenon demonstrates a poor binding of object features and location. pylyshyn’s explanation is that mot is implemented by early or low-level vision, where the information about individual identity is encapsulated and inaccessible from higher level cognition. his theory assumes that early vision picks out a small number of objects while ignoring their visual properties. because of this, object identity differentiated by visual properties is not coded or accessible from higher level cognitive processes even when the objects with those properties are attended. however, recent evidence has challenged this position by showing that tracking is content addressable (horowitz et al., ). this debate has an important implication for the present study. if the information content of tracked faces is not processed, tracking performance should not be affected by facial attractiveness. it is known that information about face identity (i.e., individuation of face stimuli by features and configurations) is not completely lost in tracking tasks (ren, chen, liu, & fu, ). if representations of the tracked faces are to some extent content addressable, there is a chance that other high-level information such as facial attractiveness is also available for processing. if processing of such information is spontaneous, this could in turn affect multiple face tracking. the experiments in this study were designed to test this hypothesis. the outcome should reveal the extent to which a high-level social cognition can penetrate and influence the low-level visual perception. appraisal for facial beauty requires high-level vision, because a main criterion for beauty—averageness—cannot be determined page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking solely from low-level visual features such as luminance, contrast, and size. computing averageness requires identifying the landmarks of higher level facial features such as the eyes, the mouth, and the face shape. the operations for image normalization, alignment, and comparison with the average in the hypothetical multi-dimensional face space also require high-level vision. to ensure that our results were controlled for the low-level contribution, we carefully scaled all our tracking stimuli to the same size, luminance, and contrast. other high-level information accompanying appraisal of facial attractiveness could also contribute to multiple-face tracking performance. as dion, berscheid, and walster ( ) showed in their seminal study, beautiful people are generally perceived to possess more positive attributes. they called this the “beauty-is-good” stereotype. many studies have since produced evidence for this positive association between attractiveness and goodness (see eagly, ashmore, makhijani, & longo, , and langlois et al., , for reviews). it is also referred to as the halo effect of attractiveness. this well established duality of beauty could predict a similar effect on tracking based on attractive and valence measures. moreover, if the reward system is involved in perception of attractive faces (kampe et al., ), arousal could also be responsible for any effect of attractiveness on tracking performance. to address these questions, we compared whether valence and arousal affect tracking performance in the same way as attractiveness. experiment the main purpose of experiment was to investigate how target and distractor attractiveness may affect tracking performance differently. given the prior finding that the target face identity is content addressable (ren et al., ), we hypothesized that the target faces could be automatically appraised for their attractiveness. attractive distractors, on the other hand, could impair tracking performance if they were also appraised for attractiveness. method page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking participants. a total of undergraduate students ( females) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision. stimuli. the face database was obtained from the university of st. andrews. it contains frontal-view caucasian faces with no external features (hair and clothing). the size of the faces was normalized according to the face width. the resulting image measured . × . cm ( . × . º) on screen. all images were scaled to the same mean luminance and root-mean-square contrast. all faces in the database were rated by raters (aged between and years, females) for attractiveness on a -point scale. to contrast the effect of attractiveness, only the most attractive and the least attractive faces were used in this experiment. the mean ratings for the two groups of faces were . ( . for females, . for males. sd = . ) and . ( . for females, . for males. sd = . ), respectively. these were significantly different from each other (p < . ). slightly more than half ( . %) of the faces were females. each attractive or unattractive face was only used once for each participant: were randomly chosen from the pool of attractive faces, and another were randomly chosen form the pool of unattractive faces. we performed an additional norming study on the face stimuli to measure how attractiveness is related to valence and arousal. twenty undergraduate students, aged between and years (m = . , sd = . ), rated a total of faces for valence and arousal. the image set consisted of the attractive and unattractive faces in this experiment as well as the additional average faces used in experiment . the faces were rated one at a time. the presentation order was random. to avoid response bias, the raters were not informed until the end of the experiment that the rating data would be used to study facial attractiveness. the details of our procedure were identical to that for the international affective picture system page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking (lang, bradley, & cuthbert, ). a -point rating scale was used where represented completely unhappy/calm, whereas completely happy/excited respectively for the valence and arousal judgments. table shows the mean rating results for each face category. to determine whether valence and arousal ratings vary according to levels of attractiveness, we conducted separate analyses of variance (anova) for the two variables. the main effect of valence was significant, f ( , ) = . , mse = . , p < . , partial η = . , where the valence for attractive faces was higher than for average-looking and unattractive faces (p < . ), and the valence for average-looking faces was higher than for unattractive faces (p < . ). on the other hand, the main effect of arousal was not significant, f ( , ) = . , mse = . , p = . , partial η = . . the tracking stimuli were displayed on a " monitor (sony trinitron, gdm-f ). a central square area with . × . º of visual angle was designated for stimulus presentation. the background color of the display was gray. e-prime (version . ) was used to generate the dynamic tracking and still displays and to control the flow of the experiment. design. we employed a within-subject design. the independent variables were target attractiveness (attractive vs. unattractive) and distractor attractiveness (attractive vs. unattractive), and face gender (male vs. female). following this design, the target faces, which were either all attractive or unattractive, were tracked among distractor faces, which were also either all attractive or unattractive. procedure. participants were tested individually. an adjustable headrest was used to fix the participant's viewing position, which was set cm away from the computer monitor. the faces presented in each trial were of the same sex. they were randomly chosen for each trial from the pool of faces. the chosen images were not repeated in the subsequent trials until all faces in the pool were used. the procedure for each trial of the experiments is illustrated in figure a. each trial was initiated by a key press. it began with stationary black page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking rectangles on the screen. the location of the rectangles was randomly assigned, with the constraint that none would occlude the others and the center-to-center distance was not less than twice of their size. five of the rectangles would then start to blink twice for s, signaling the target location. following this, the rectangles changed abruptly into faces, and started to move in random directions. the faces bounced off each other when the center-to-center distance was less than twice of their size. they avoided the edge of the display area when the center to edge distance was less than their size. participants were asked to track the five moving targets. the velocity of the face images varied between . and . º / s with a mean of . º / s. all faces moving about the screen for s. as soon as the motion stopped, all the faces were again occluded by black rectangles. the task was to pick out the five targets by clicking on the rectangles. once being clicked, the rectangle was highlighted with a yellow border which could be switched on and off by clicking. participants were forced to select items and were allowed to guess. once items were selected, they clicked a “finish” button to start the next trial. the experiment lasted about minutes. a total of experimental trials were run after practice trials. each of the eight conditions ( target attractiveness × distractor attractiveness × face gender) had trials. all trials were mixed in random order in one block. results and discussion an alpha level of . was used for all statistical analyses in this report. results of tracking accuracy are shown in figure . the data were analyzed using repeated-measures anova. there was a significant main effect of target attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , where attractive faces were tracked better than unattractive faces. however, there was no difference between results for attractive and unattractive distractors, f ( , ) = . , mse = . , p = . , partial η = . . there was also a main effect of face gender, f ( , ) = . , mse = . , p < . , partial η = . , where male page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking faces were tracked better than female faces. however, face gender did not interact with other factors, ps > . . none of the other two-way or three-way interactions was significant, ps > . . the experiment shows that tracking performance was affected by appraisal of facial attractiveness. this effect was only present for the target faces, while the influence of attractive distractors was negligible. although male faces were tracked better than female faces, the effect was not modulated by attractiveness. the effect of attractive faces on tracking performance could be due to varying levels of involuntary attention to task-irrelevant information. some participants might be able to suppress or control attention to the task-irrelevant information better than others. if this is the case, it would be possible that those who were poor at the tracking task would show a stronger attractiveness effect, because they are poor at suppressing the attractiveness information. to test this prediction, we analyzed the correlation between the size of attractiveness effect and overall tracking performance. consistent with this prediction, a negative correlation was found between the two, r = - . , p < . . figure a shows a scatter plot of this correlation. because the attractive faces had greater valence rating than unattractive faces in our norming study, we evaluated how the difference of valence contributed to the attractiveness effect in this experiment. this was done by an item-based analysis of covariance (ancova), where facial attractiveness was treated as a random factor, and the valence a covariate. ancova measures whether attractiveness had an effect on tracking performance after removing the covariate valence. because only the target attractiveness had an effect on tracking performance, we only used target attractiveness in our ancova as an independent factor. hence the target faces were used as random sample, and corresponding valence for these faces as covariate. results showed a significant main effect of target attractiveness, f ( , page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking ) = . , mse = . , p < . , partial η = . , where attractive targets were tracked better than unattractive targets. however, the covariate was not significant, f ( , ) =. , mse =. , p = . , partial η = . , suggesting that the valence made no contribution to the attractiveness effect found in this experiment. experiment in experiment , the target faces were either attractive or unattractive. when the targets had a similar level of attractiveness, attention might be more or less evenly distributed among the targets. however, if attractiveness varies considerably among targets, attention and consequently tracking performance for a given target could be affected by its attractiveness relative to other targets. to test this hypothesis, we varied level of target attractiveness in this experiment such that the targets consisted of attractive, average, and unattractive faces. we then compared the performance for these different types of targets. another issue concerning the use of all attractive or all unattractive targets was that attractive faces may be more visually similar to one another than unattractive faces. yantis ( ) showed that similarity among targets improves tracking. because of this, the tracking advantage for attractive targets may not reflect attractiveness directly, but rather through featural similarity. the design in the present experiment was able to eliminate this problem because an effect of attractiveness would no longer be due to greater similarity among the attractive targets. method participants. a different group of undergraduate students ( females and males) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision. stimuli. the attractive and unattractive face stimuli were the same as in experiments and . in addition, we also added average-looking faces. the mean ratings for the page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking average-looking faces was . (sd = . , n = ). as in the previous experiments, each face category consisted of faces randomly selected from the respective pool of stimuli for each participant. each trial contained one attractive, one unattractive, and three average-looking target faces. the distractors in this experiment consisted of average-looking faces. because average faces were used in each trial and trials in total, this requires a total of average faces ( × ). since there were average faces available, each face was repeated about times ( ÷ = . ). design. this was again a within-subject design. the independent variables were target attractiveness (attractive, average, and unattractive) and face gender. because experiment showed no effect of distractor attractiveness, this variable was not included in this and the next experiments. procedure. this was identical to experiment . results and discussion the tracking results are shown in figure . the main effect of target attractiveness was significant, f ( , ) = . , mse = . , p < . , partial η = . . no significant effect was found for face gender, f ( , ) = . , mse = . , p = . , or interaction between face gender and target attractiveness, f ( , ) = . , mse = . , p = . . post hoc comparisons of means with bonferroni correction revealed better tracking performance for attractive targets relative to average or unattractive targets ts ( ) > . , ps < . . there was no difference between results for average and unattractive targets, t ( ) = . , p = . . the results suggest that attractive faces were attended more favourably whereas unattractive and average-looking faces were not treated differently during tracking. consistent with experiment , there was a significant negative correlation between participants’ overall tracking performance and the size of the attractiveness effect, r = - . , p < . . a scatter plot of this correlation is shown in figure b. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking results of ancova for experiment show that there was a significant main effect of target attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , where attractive faces were tracked better than average-looking and unattractive faces (ps < . ), and there was no difference between average-looking faces and unattractive faces (p = . ). the covariate, or valence of the faces, was also significantly related to the tracking performance, f ( , ) = . , mse = . , p < . , partial η = . . this indicates that the valence of faces also contributed to the attractiveness effect in this experiment. experiment the tracking task in experiments and did not explicitly require binding of a target identity with its location. if target attractiveness is appraised, it is possible that the location of an attractive target is monitored more accurately relative to an unattractive target. to test this hypothesis, we employed a variant of the mot paradigm, where one of the faces was randomly chosen from the targets and probed at the end of each trial. the task here was to specify the location of the probe face. method participants. a different group of undergraduate students ( females and males) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision. stimuli. these were the same as experiment . design. this was again a within-subject design. the independent variables were attractiveness, face gender, and participant gender. although not originally planned, potential participant gender difference was included in our analysis because the number of participants in each gender group was fully balanced. procedure. the procedure of this experiment was identical to experiment except that at the end of each trial one of the faces was randomly chosen from the targets and probed (see page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking figure b). the participant was required to specify the specific location of the probe face by clicking on one of the occluded faces with a mouse. the occluder of the chosen face was then removed to reveal the answer after the mouse click. this feedback was used to engage the participants. because this task was harder than the standard task, the number of faces in each trial was reduced to , with the number of target faces reduced to . the task began with four practice trials followed by experimental trials ( trials × conditions). results and discussion the locations of attractive targets were identified better than unattractive targets, f ( , ) = . , mse = . , p < . , partial η = . . neither face gender nor participant gender produced a significant main effect, fs ( , ) = . and . , ps = . and . , respectively. however, this was qualified by a significant two-way interaction between participant gender and attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , as well as a marginally significant interaction between participant gender and face gender, f ( , ) = . , mse = . , p = . , partial η = . . the three-way interaction also approached the level of significance, f ( , ) = . , mse = . , p = . , partial η = . . the two-way interaction between face gender and attractiveness was not significant, ( , ) = . , p = . , partial η = . . the interaction effects are illustrated in figure . to investigate the interaction effects, we conducted separate anovas for the two participant genders. results for the female participants showed a significant main effects of attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , and face gender, f ( , ) = . , mse = . , p < . , partial η = . . there was also a significant interaction between attractiveness and face gender, f ( , ) = . , mse = . , p < . , partial η = . . further analyses of the interaction via pairwise comparisons of means revealed that female participants identified the spatial locations for attractive male targets more accurately than for unattractive male targets, t ( ) = . , p < . . in contrast, the page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking locations for these attractive and unattractive male targets were identified equally well by male participants, t ( ) = - . , p = . . in contrast to the results for female participants, anova did not find any main effects of face gender and attractiveness, or the interaction between the two for the male participants, fs ( , ) < . , ps > . . consistent with experiments and , the performance was again negatively correlated with the size of attractiveness effect, r = - . , p < . . figure c shows a scatter plot of this correlation. to determine whether valence has also contributed to tracking performance, we performed an ancova on the data following the same statistical procedure as experiment . results showed a significant main effect of target attractiveness, f ( , ) = . , mse =. , p < . , partial η = . , where attractive faces were tracked better than unattractive faces. the valence, as a covariate, did not significantly affect the tracking performance, f ( , ) =. , mse =. , p = . , partial η < . . the data in this experiment suggest that an attractive target was more likely to create a stronger identity-location binding in female participants for attractive male targets. the difference between identity-location binding for attractive and unattractive female targets was not significant. consistent with experiment , valence did not contribute to the binding advantage of attractive targets. general discussion results in these experiments suggest a facilitative effect of facial attractiveness in multiple-face tracking. experiment showed a better tracking performance when attractive faces were assigned as targets. experiment showed that attractive targets were more likely to be tracked successfully when they were mixed with unattractive or average looking targets. finally, experiment found that attractive targets could induce a stronger binding of face identity and location. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking given that attractive faces may be more visually similar to one another than unattractive faces and that yantis ( ) showed that similarity among targets improves tracking, one may argue that the tracking advantage for attractive targets may not reflect attractiveness directly, but rather through featural similarity. the replicated attractiveness advantage of experiment has eliminated this equivocal problem. furthermore, attractive targets and attractive distractors were likely to be more similar than unattractive targets and unattractive distractors in experiments and . this may make tracking more difficult (makovski & jiang, ) and predict an opposite unattractiveness advantage. from this point, the tracking advantage for attractive targets is less likely to reflect featural similarity of attractive faces. facial beauty would not produce an effect on these tracking tasks if facial features and their holistic information were not processed during the process of tracking. therefore, given the pattern of our results, the representations of the target items must be content addressable. there is already evidence that face or object identities are processed in multiple target tracking (horowitz et al., ; oksama & hyönä, ; ren et al., ). the present study shows further that facial attractiveness is also processed during tracking. as the results in experiment indicate, attractiveness appeared to be assessed only for the target items, because distractors had negligible effects on tracking performance. this finding is consistent with the observation that only target identity is processed in multiple-object or multiple-face tracking (pylyshyn, ; ren et al., ). contrary to the suggestion that multiple object tracking is purely driven by low-level vision, of which higher level cognitive processes are unable to penetrate, tracking performance appeared to be modulated by the information content of target items. content addressability may depend on whether the information is important to the observer and whether the observer is predisposed to process the type of information. like face identity, attractive faces may automatically engage the attention system. the appraisal for page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking attractiveness in our experiments was spontaneous because it was task irrelevant. although the effects of such automatic appraisal in this and other studies (e.g., sui & liu, ) can be quite small, they are consistent and replicable. a small effect in these studies may suggest that task-irrelevant processing can be largely suppressed by the central control. the present study revealed that a participant’s tracking performance was negatively correlated with the size of attractiveness effect. this suggests that some individuals may have weaker central control than others: those who were not as good at tracking showed a larger attractiveness effect because they might not have as much central control and were more easily distracted by the irrelevant information. perhaps due to the extent of the central control, not all evidence to date shows that appraisal of attractiveness is spontaneous or mandatory. schacht, werheid, and sommer ( ) found that attractiveness appraisal depended on whether facial attractiveness was task relevant (e.g., beauty rating). this led them to conclude that attractiveness appraisal requires voluntary attention to the attractiveness dimension. the findings of our study show that facial attractiveness can be appraised even when it is not task relevant. our analyses of the correlation between the effect of attractiveness and tracking performance in the three experiments provide preliminary evidence that participants with higher tracking performance tend to produce a smaller attractiveness effect. this may be due to these participants’ better central control to suppress task-irrelevant appraisal of facial attractiveness. task irrelevant processing of facial beauty has been reported in brain research. chatterjee, thomas, smith and aguirre ( ) found that the ventral occipital region remained responsive to facial beauty when the task of their participants was to judge facial identity rather than to attend explicitly to attractiveness. they proposed that this region, which includes the fusiform gyrus, the lateral occipital cortex and medially adjacent regions, is activated automatically by beauty and may serve as a neural trigger for pervasive effects of attractiveness in social interactions page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking (see also kampe et al., ). undoubtedly, the exact level of control that the central executive can have over automatic processing of certain task-irrelevant stimuli will require systematic future research. the present study also provides preliminary evidence that target tracking is spontaneously affected by gender detection. experiment showed that male faces were tracked better than female faces. this could be due to a gender bias as participants in this experiment were mainly comprised of females. when we tested equal number of male and female participants in experiment , results showed that female participants tracked the location of an attractive male face more accurately relative to an unattractive male face. however, it is unclear why the same effect was not found for female faces. the gender effect found in experiment may be similar to bayliss et al ( ), who found that averted eyes of a face or nonpredictive arrows produce a stronger reflexive shift of attention in females than in males. given that the participants in our experiments and were predominantly females, the results in these experiments could be largely driven by certain aspects of gender difference. the role of gender difference in attentive tracking is therefore an important area for future investigation. consistent with prior research, attractive face stimuli in this study were also rated more positively on the valence dimension. although valence did not contribute to the tracking advantage of attractive faces when the tracked faces had similar attractiveness (experiments and ), it did contribute to the tracking performance when the target faces consisted of a full range of attractiveness (experiment ). thus, the lack of valence effect in experiments and may be due to the much smaller range of this variable associated with the attractive targets. positive valence is a central trait of facial beauty. it is therefore not surprising that it produced a similar effect to attractiveness on distributed attention. it should be noted, however, that the differences in valence ratings of attractive and non-attractive faces were quite small. no page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking significant difference was found in arousal ratings of attractive and non-attractive faces. these rating data may suggest a moderate link between facial attractiveness and valence, whereas the link between facial attractiveness and arousal is negligible. although it is difficult to separate attractiveness from positive valence due to the very nature of beauty, it is possible to study whether valence in other types of stimuli produces a similar effect on multiple object tracking. a similar conclusion can be made about the relationship between attractiveness and averageness. it would not be possible to separate attractiveness from averageness because averageness is a defining feature of attractiveness. however, it is possible to study whether averageness in non-face stimuli also produces a similar advantage in a multiple object tracking task. there is little evidence that averageness in other kinds of stimuli also attracts attention although it is highly likely that beautiful things in general attract more attention. unlike faces, the relationship between averageness and other types of beautiful things remains to be seen. in face research, this relationship is established through image morphing techniques. however, it is often difficult to use the same method that requires well-defined corresponding features to build an average for other categories of things such as beautiful sunsets, because obvious correspondence in such images is often absent. the attentional bias for attractive faces found in this study suggests that multiple object tracking is modulated by underlying biological significance of the tracked targets. it may reflect biological interests of the observer. the preference for attractive faces may be deeply rooted in evolution (langlois et al., ; rhodes, ). prior research has demonstrated an automatic reaction to facial beauty in focalized attention. the present study shows a similar response to beauty in distributed attention. because multiple object tracking depends on attentional resources in the working memory (oksama & hyona, ), our results may suggest higher working memory capacity and greater attentional resources for attractive page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking faces. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking author notes this research was supported by grants from the royal society, kc wong foundation, and program ( cb ). we thank professor david perrett for offering the face stimuli, and emma medford for her thoughtful comments on an earlier version of this manuscript. we especially thank the reviewers for their constructive comments and suggestions. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking footnote we thank dr. trafton drew for suggesting this idea. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking references aharon, i., etcoff, n., ariely, d., chabris, c. f., o’connor, e., & breiter, h. c. 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( ). can beauty be ignored? effects of facial attractiveness on covert attention. psychonomic bulletin & review, , - . page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking yantis, ( ). multielement visual tracking: attention and perceptual organization. cognitive psychology, , - . page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking table mean ratings of valence and arousal. values in parentheses represent standard deviation. ____________________________________________ attractiveness valence arousal ____________________________________________ attractive . ( . ) . ( . ) average . ( . ) . ( . ) unattractive . ( . ) . ( . ) ____________________________________________ page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking figure captions figure . illustration of the procedure used in the study. a. procedure used in experiments and . b. procedure used in experiment . figure . tracking accuracy in experiment as a function of target and distractor attractiveness. a. results of male faces. b. results of female faces. error bars represent standard errors. figure . scatter plots for the correlation between the size of attractiveness effect and tracking performance. figure . tracking accuracy in experiment as a function of target attractiveness and face gender. error bars represent standard errors. figure . tracking accuracy in experiment as a function of target attractiveness and face gender. a. results of male faces. b. results of female faces. error bars represent standard errors. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology figure . illustration of the procedure used in the study. a. procedure used in experiments and . b. procedure used in experiment . x mm ( x dpi) page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology figure . tracking accuracy in experiment as a function of target and distractor attractiveness. a. results of male faces. b. results of female faces. error bars represent standard errors. x mm ( x dpi) page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology figure . scatter plots for the correlation between the size of attractiveness effect and tracking performance. x mm ( x dpi) page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology figure . tracking accuracy in experiment as a function of target attractiveness and face gender. error bars represent standard errors. x mm ( x dpi) page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology figure . tracking accuracy in experiment as a function of target attractiveness and face gender. a. results of male faces. b. results of female faces. error bars represent standard errors. x mm ( x dpi) page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking running head: attractiveness affects multiple-face tracking beauty is better pursued: effects of attractiveness in multiple-face tracking chang hong liu university of hull wenfeng chen chinese academy of sciences correspondences: chang hong liu, phd wenfeng chen, phd department of psychology institute of psychology university of hull chinese academy of sciences cottingham road a datun road hull, hu rx chaoyang district, beijing united kingdom china tel: + - tel: + - fax: + - fax: + - email: c.h.liu@hull.ac.uk email: chenwf@psych.ac.cn abstract using the multiple-object tracking paradigm, this study examines how spontaneous appraisal page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology mailto:chenwf@psych.ac.cn attractiveness affects multiple-face tracking for facial beauty affects distributed attention to multiple faces in dynamic displays. observers tracked attractive faces more effectively relative to unattractive faces in this task. tracking performance was only affected by target attractiveness, suggesting an absence of appraisal for distractor attractiveness. attractive male faces also produced stronger binding of face identity and location for female participants. together, the results suggest that facial attractiveness was appraised during tracking even though this was task irrelevant. contrary to the theory that multiple-object tracking is driven by encapsulated low-level vision, our results show that the content of target representation is not only penetrable by social cognition but also modulates the course of tracking operations. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking beauty is better pursued: effects of attractiveness in multiple-face tracking it is well known that human observers pay greater attention to faces than to non-face objects (e.g., ro, russell, & lavie, ). moreover, some face stimuli attract more attention than others. apart from certain facial expressions such as fear and anger (palermo & rhodes, ), attractive faces also trigger greater attention (sui & liu, ). popular culture often suggests that a mere glance of a face elicits spontaneous appraisal of attractiveness. humans may be predisposed to direct attention to attractive faces because of their biological and social significance. there is well-established evidence that even newborn babies look at attractive faces longer (e.g., geldart, maurer, & carney, ; langlois et al., ; samuels et al., ; slater et al., ). adults also tend to spend more time looking at beautiful faces (aharon et al., ; kranz & ishai, ), which are known to activate dopaminergic regions in the brain that are strongly linked to the reward system (kampe, frith, dolan, & frith, ). appraisal of facial beauty appears to depend on how well a face resembles the average in a population (langlois & roggman, ). although symmetry also plays a role in facial beauty (e.g., grammer & thornhill, ), there is evidence that it is less important than averageness (rhodes, sumich, & byatt, ; also see rhodes, , for an extensive review). hence attentional capture by attractive faces may rely on preattentive computation of averageness in face stimuli. however, little is known about how facial attractiveness affects attentional mechanisms. this issue may be addressed through the existing attention paradigms. for example, maner, gailliot, and dewall ( ) employed a dot-probe paradigm to assess the effect of attractiveness on disengaging attention. consistent with their hypothesis, their observers were slower at page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking disengaging attention from attractive female faces relative to average-looking female or male faces. in another study, maner, gailliot, rouby, and miller ( ) used the same method and found that participants fixated on highly attractive faces within the first half second and took longer to stop looking at them when asked to shift their attention away. in a different approach, sui and liu ( ) investigated whether appraisal for attractiveness occurs when spatial attention has already been directed elsewhere. they employed a spatial cuing task, where participants were asked to judge the orientation of a cued target presented to the left or right visual field while ignoring a task-irrelevant face image flashed in the opposite field. they found that the presence of attractive faces significantly lengthened task performance. this suggests that facial beauty can automatically compete with an ongoing task for attention, although this does not necessarily mean that appraisal of facial beauty is a mandatory process (see schacht, werheid, & sommer, ). the analysis of eye movements in sui and liu’s study revealed that the effect of facial attractiveness was not due to foveal fixation on the target or face stimuli, hence there is a strong possibility that facial attractiveness can be detected outside the fovea. this has been confirmed by a recent investigation, where discrimination of facial beauty was measured at several eccentricities (guo, liu, & roebuck, ). both dot-probe and cuing tasks require focused attention, where attention is directed to a single spatial location. however, attention in reality can be distributed to several different targets or spatial locations. for instance, a group activity requires attention to be paid to multiple individuals and locations. the main purpose of this research was to investigate the effect of facial attractiveness on distributed attention. another motivation of this research comes from observation that spontaneous appraisal of attractiveness is rapid and transient (schacht et al., ). it remains unclear whether such an appraisal only manifests in brief attentional shifts. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking hence the second purpose of this study was to investigate whether a similar kind of automatic appraisal for facial attractiveness occurs continuously when sustained attention is distributed among faces in multiple locations. pylyshyn and storm ( ) designed a multiple-object tracking paradigm (mot) to study how human observers maintain attention on multiple objects across space and time. in recent years, the issue of content addressability in object tracking is hotly debated. this issue was first raised by pylyshyn ( ) who found that observers were remarkably poor at identifying the features or identity of correctly tracked objects. this phenomenon demonstrates a poor binding of object features and location. pylyshyn’s explanation is that mot is implemented by early or low-level vision, where the information about individual identity is encapsulated and inaccessible from higher level cognition. his theory assumes that early vision picks out a small number of objects while ignoring their visual properties. because of this, object identity differentiated by visual properties is not coded or accessible from higher level cognitive processes even when the objects with those properties are attended. however, recent evidence has challenged this position by showing that tracking is content addressable (horowitz et al., ). this debate has an important implication for the present study. if the information content of tracked faces is not processed, tracking performance should not be affected by facial attractiveness. it is known that information about face identity (i.e., individuation of face stimuli by features and configurations) is not completely lost in tracking tasks (ren, chen, liu, & fu, ). if representations of the tracked faces are to some extent content addressable, there is a chance that other high-level information such as facial attractiveness is also available for processing. if processing of such information is spontaneous, this could in turn affect multiple page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking face tracking. the experiments in this study were designed to test this hypothesis. the outcome should reveal the extent to which a high-level social cognition can penetrate and influence the low-level visual perception. appraisal for facial beauty requires high-level vision, because a main criterion for beauty—averageness—cannot be determined solely from low-level visual features such as luminance, contrast, and size. computing averageness requires identifying the landmarks of higher level facial features such as the eyes, the mouth, and the face shape. the operations for image normalization, alignment, and comparison with the average in the hypothetical multi-dimensional face space also require high-level vision. to ensure that our results were controlled for the low-level contribution, we carefully scaled all our tracking stimuli to the same size, luminance, and contrast. other high-level information accompanying appraisal of facial attractiveness could also contribute to multiple-face tracking performance. as dion, berscheid, and walster ( ) showed in their seminal study, beautiful people are generally perceived to possess more positive attributes. they called this the “beauty-is-good” stereotype. many studies have since produced evidence for this positive association between attractiveness and goodness (see eagly, ashmore, makhijani, & longo, , and langlois et al., , for reviews). it is also referred to as the halo effect of attractiveness. this well established duality of beauty could predict a similar effect on tracking based on attractive and valence measures. moreover, if the reward system is involved in perception of attractive faces (kampe et al., ), arousal could also be responsible for any effect of attractiveness on tracking performance. to address these questions, we compared whether valence and arousal affect tracking performance in the same way as attractiveness. experiment the main purpose of experiment was to investigate how target and distractor page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking attractiveness may affect tracking performance differently. given the prior finding that the target face identity is content addressable (ren et al., ), we hypothesized that the target faces could be automatically appraised for their attractiveness. attractive distractors, on the other hand, could impair tracking performance if they were also appraised for attractiveness. method participants. a total of undergraduate students ( females) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision. stimuli. the face database was obtained from the university of st. andrews. it contains frontal-view caucasian faces with no external features (hair and clothing). the size of the faces was normalized according to the face width. the resulting image measured . × . cm ( . × . º) on screen. all images were scaled to the same mean luminance and root-mean-square contrast. all faces in the database were rated by raters (aged between and years, females) for attractiveness on a -point scale. to contrast the effect of attractiveness, only the most attractive and the least attractive faces were used in this experiment. the mean ratings for the two groups of faces were . ( . for females, . for males. sd = . ) and . ( . for females, . for males. sd = . ), respectively. these were significantly different from each other (p < . ). slightly more than half ( . %) of the faces were females. each attractive or unattractive face was only used once for each participant: were randomly chosen from the pool of attractive faces, and another were randomly chosen form the pool of unattractive faces. we performed an additional norming study on the face stimuli to measure how attractiveness page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking is related to valence and arousal. twenty undergraduate students, aged between and years (m = . , sd = . ), rated a total of faces for valence and arousal. the image set consisted of the attractive and unattractive faces in this experiment as well as the additional average faces used in experiment . the faces were rated one at a time. the presentation order was random. to avoid response bias, the raters were not informed until the end of the experiment that the rating data would be used to study facial attractiveness. the details of our procedure were identical to that for the international affective picture system (lang, bradley, & cuthbert, ). a -point rating scale was used where represented completely unhappy/calm, whereas completely happy/excited respectively for the valence and arousal judgments. table shows the mean rating results for each face category. to determine whether valence and arousal ratings vary according to levels of attractiveness, we conducted separate analyses of variance (anova) for the two variables. the main effect of valence was significant, f ( , ) = . , mse = . , p < . , partial η = . , where the valence for attractive faces was higher than for average-looking and unattractive faces (p < . ), and the valence for average-looking faces was higher than for unattractive faces (p < . ). on the other hand, the main effect of arousal was not significant, f ( , ) = . , mse = . , p = . , partial η = . . the tracking stimuli were displayed on a " monitor (sony trinitron, gdm-f ). a central square area with . × . º of visual angle was designated for stimulus presentation. the background color of the display was gray. e-prime (version . ) was used to generate the dynamic tracking and still displays and to control the flow of the experiment. design. we employed a within-subject design. the independent variables were target attractiveness (attractive vs. unattractive) and distractor attractiveness (attractive vs. unattractive), and face gender (male vs. female). following this design, the target faces, which were either all page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking attractive or unattractive, were tracked among distractor faces, which were also either all attractive or unattractive. procedure. participants were tested individually. an adjustable headrest was used to fix the participant's viewing position, which was set cm away from the computer monitor. the faces presented in each trial were of the same sex. they were randomly chosen for each trial from the pool of faces. the chosen images were not repeated in the subsequent trials until all faces in the pool were used. the procedure for each trial of the experiments is illustrated in figure a. each trial was initiated by a key press. it began with stationary black rectangles on the screen. the location of the rectangles was randomly assigned, with the constraint that none would occlude the others and the center-to-center distance was not less than twice of their size. five of the rectangles would then start to blink twice for s, signaling the target location. following this, the rectangles changed abruptly into faces, and started to move in random directions. the faces bounced off each other when the center-to-center distance was less than twice of their size. they avoided the edge of the display area when the center to edge distance was less than their size. participants were asked to track the five moving targets. the velocity of the face images varied between . and . º / s with a mean of . º / s. all faces moving about the screen for s. as soon as the motion stopped, all the faces were again occluded by black rectangles. the task was to pick out the five targets by clicking on the rectangles. once being clicked, the rectangle was highlighted with a yellow border which could be switched on and off by clicking. participants were forced to select items and were allowed to guess. once items were selected, they clicked a “finish” button to start the next trial. the experiment lasted about minutes. a total of experimental trials were run after practice trials. each of the eight conditions ( target attractiveness × distractor attractiveness × face gender) had trials. all trials page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking were mixed in random order in one block. results and discussion an alpha level of . was used for all statistical analyses in this report. results of tracking accuracy are shown in figure . the data were analyzed using repeated-measures anova. there was a significant main effect of target attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , where attractive faces were tracked better than unattractive faces. however, there was no difference between results for attractive and unattractive distractors, f ( , ) = . , mse = . , p = . , partial η = . . there was also a main effect of face gender, f ( , ) = . , mse = . , p < . , partial η = . , where male faces were tracked better than female faces. however, face gender did not interact with other factors, ps > . . none of the other two-way or three-way interactions was significant, ps > . . the experiment shows that tracking performance was affected by appraisal of facial attractiveness. this effect was only present for the target faces, while the influence of attractive distractors was negligible. although male faces were tracked better than female faces, the effect was not modulated by attractiveness. the effect of attractive faces on tracking performance could be due to varying levels of involuntary attention to task-irrelevant information. some participants might be able to suppress or control attention to the task-irrelevant information better than others. if this is the case, it would be possible that those who were poor at the tracking task would show a stronger attractiveness effect, because they are poor at suppressing the attractiveness information. to test this prediction, we analyzed the correlation between the size of attractiveness effect and overall tracking performance. consistent with this prediction, a negative correlation was found between the two, r = - . , p < . . figure a shows a scatter plot of this correlation. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking because the attractive faces had greater valence rating than unattractive faces in our norming study, we evaluated how the difference of valence contributed to the attractiveness effect in this experiment. this was done by an item-based analysis of covariance (ancova), where facial attractiveness was treated as a random factor, and the valence a covariate. ancova measures whether attractiveness had an effect on tracking performance after removing the covariate valence. because only the target attractiveness had an effect on tracking performance, we only used target attractiveness in our ancova as an independent factor. hence the target faces were used as random sample, and corresponding valence for these faces as covariate. results showed a significant main effect of target attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , where attractive targets were tracked better than unattractive targets. however, the covariate was not significant, f ( , ) =. , mse =. , p = . , partial η = . , suggesting that the valence made no contribution to the attractiveness effect found in this experiment. experiment in experiment , the target faces were either attractive or unattractive. when the targets had a similar level of attractiveness, attention might be more or less evenly distributed among the targets. however, if attractiveness varies considerably among targets, attention and consequently tracking performance for a given target could be affected by its attractiveness relative to other targets. to test this hypothesis, we varied level of target attractiveness in this experiment such that the targets consisted of attractive, average, and unattractive faces. we then compared the performance for these different types of targets. another issue concerning the use of all attractive or all unattractive targets was that attractive faces may be more visually similar to one another than unattractive faces. yantis ( ) showed that similarity among targets improves tracking. because of this, the tracking advantage page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking for attractive targets may not reflect attractiveness directly, but rather through featural similarity. the design in the present experiment was able to eliminate this problem because an effect of attractiveness would no longer be due to greater similarity among the attractive targets. method participants. a different group of undergraduate students ( females and males) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision. stimuli. the attractive and unattractive face stimuli were the same as in experiments and . in addition, we also added average-looking faces. the mean ratings for the average-looking faces was . (sd = . , n = ). as in the previous experiments, each face category consisted of faces randomly selected from the respective pool of stimuli for each participant. each trial contained one attractive, one unattractive, and three average-looking target faces. the distractors in this experiment consisted of average-looking faces. because average faces were used in each trial and trials in total, this requires a total of average faces ( × ). since there were average faces available, each face was repeated about times ( ÷ = . ). design. this was again a within-subject design. the independent variables were target attractiveness (attractive, average, and unattractive) and face gender. because experiment showed no effect of distractor attractiveness, this variable was not included in this and the next experiments. procedure. this was identical to experiment . results and discussion the tracking results are shown in figure . the main effect of target attractiveness was significant, f ( , ) = . , mse = . , p < . , partial η = . . no significant effect was page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking found for face gender, f ( , ) = . , mse = . , p = . , or interaction between face gender and target attractiveness, f ( , ) = . , mse = . , p = . . post hoc comparisons of means with bonferroni correction revealed better tracking performance for attractive targets relative to average or unattractive targets ts ( ) > . , ps < . . there was no difference between results for average and unattractive targets, t ( ) = . , p = . . the results suggest that attractive faces were attended more favourably whereas unattractive and average-looking faces were not treated differently during tracking. consistent with experiment , there was a significant negative correlation between participants’ overall tracking performance and the size of the attractiveness effect, r = - . , p < . . a scatter plot of this correlation is shown in figure b. results of ancova for experiment show that there was a significant main effect of target attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , where attractive faces were tracked better than average-looking and unattractive faces (ps < . ), and there was no difference between average-looking faces and unattractive faces (p = . ). the covariate, or valence of the faces, was also significantly related to the tracking performance, f ( , ) = . , mse = . , p < . , partial η = . . this indicates that the valence of faces also contributed to the attractiveness effect in this experiment. experiment the tracking task in experiments and did not explicitly require binding of a target identity with its location. if target attractiveness is appraised, it is possible that the location of an attractive target is monitored more accurately relative to an unattractive target. to test this hypothesis, we employed a variant of the mot paradigm, where one of the faces was randomly chosen from the targets and probed at the end of each trial. the task here was to specify the deleted: experiment page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking location of the probe face. method participants. a different group of undergraduate students ( females and males) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision. stimuli. these were the same as experiment . design. this was again a within-subject design. the independent variables were attractiveness, face gender, and participant gender. although not originally planned, potential participant gender difference was included in our analysis because the number of participants in each gender group was fully balanced. procedure. the procedure of this experiment was identical to experiment except that at the end of each trial one of the faces was randomly chosen from the targets and probed (see figure b). the participant was required to specify the specific location of the probe face by clicking on one of the occluded faces with a mouse. the occluder of the chosen face was then removed to reveal the answer after the mouse click. this feedback was used to engage the participants. because this task was harder than the standard task, the number of faces in each trial was reduced to , with the number of target faces reduced to . the task began with four practice trials followed by experimental trials ( trials × conditions). results and discussion the locations of attractive targets were identified better than unattractive targets, f ( , ) = . , mse = . , p < . , partial η = . . neither face gender nor participant gender produced a significant main effect, fs ( , ) = . and . , ps = . and . , respectively. however, this was qualified by a significant two-way interaction between participant gender and deleted: more balanced than experiment . however, it should be stressed that because gender difference was not originally planned as an aim of this study, the number of participants in each gender group was far from balanced. also, because experiment showed no effect of distractor attractiveness, this variable was not included in this and the next experiments. the distractors were selected in the same way as in experiment page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , as well as a marginally significant interaction between participant gender and face gender, f ( , ) = . , mse = . , p = . , partial η = . . the three-way interaction also approached the level of significance, f ( , ) = . , mse = . , p = . , partial η = . . the two-way interaction between face gender and attractiveness was not significant, ( , ) = . , p = . , partial η = . . the interaction effects are illustrated in figure . to investigate the interaction effects, we conducted separate anovas for the two participant genders. results for the female participants showed a significant main effects of attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , and face gender, f ( , ) = . , mse = . , p < . , partial η = . . there was also a significant interaction between attractiveness and face gender, f ( , ) = . , mse = . , p < . , partial η = . . further analyses of the interaction via pairwise comparisons of means revealed that female participants identified the spatial locations for attractive male targets more accurately than for unattractive male targets, t ( ) = . , p < . . in contrast, the locations for these attractive and unattractive male targets were identified equally well by male participants, t ( ) = - . , p = . . in contrast to the results for female participants, anova did not find any main effects of face gender and attractiveness, or the interaction between the two for the male participants, fs ( , ) < . , ps > . . consistent with experiments and , the performance was again negatively correlated with the size of attractiveness effect, r = - . , p < . . figure c shows a scatter plot of this correlation. to determine whether valence has also contributed to tracking performance, we performed an ancova on the data following the same statistical procedure as experiment . results deleted: face deleted: male faces deleted: effect deleted: ) = . deleted: . deleted: deleted: , and deleted: participant deleted: ) = . deleted: . deleted: . the main effect of participant gender was not significant, f ( , ) = . , mse = . , p = . , partial η = . deleted: male faces deleted: participant deleted: female faces deleted: ) < . deleted: deleted: experiment deleted: b page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking showed a significant main effect of target attractiveness, f ( , ) = . , mse =. , p < . , partial η = . , where attractive faces were tracked better than unattractive faces. the valence, as a covariate, did not significantly affect the tracking performance, f ( , ) =. , mse =. , p = . , partial η < . . the data in this experiment suggest that an attractive target was more likely to create a stronger identity-location binding in female participants for attractive male targets. the difference between identity-location binding for attractive and unattractive female targets was not significant. consistent with experiment , valence did not contribute to the binding advantage of attractive targets. general discussion results in these experiments suggest a facilitative effect of facial attractiveness in multiple-face tracking. experiment showed a better tracking performance when attractive faces were assigned as targets. experiment showed that attractive targets were more likely to be tracked successfully when they were mixed with unattractive or average looking targets. finally, experiment found that attractive targets could induce a stronger binding of face identity and location. given that attractive faces may be more visually similar to one another than unattractive faces and that yantis ( ) showed that similarity among targets improves tracking, one may argue that the tracking advantage for attractive targets may not reflect attractiveness directly, but rather through featural similarity. the replicated attractiveness advantage of experiment has eliminated this equivocal problem. furthermore, attractive targets and attractive distractors were likely to be more similar than unattractive targets and unattractive distractors in experiments and . this may make tracking more difficult (makovski & jiang, ) and predict an opposite deleted: experiment ¶ in both experiments and , the target faces were either attractive or unattractive. when the targets had a similar level of attractiveness, attention might be more or less evenly distributed among the targets. however, if attractiveness varies considerably among targets, attention and consequently tracking performance for a given target could be affected by its attractiveness relative to other targets. to test this hypothesis, we varied level of target attractiveness in this experiment such that the targets consisted of attractive, average, and unattractive faces. we then compared the performance for these different types of targets. ¶ another issue concerning the use of all attractive or all unattractive targets was that attractive faces may be more visually similar to one another than unattractive faces. yantis ( ) showed that similarity among targets improves tracking. because of this, the tracking advantage for attractive targets may not reflect attractiveness directly, but rather through featural similarity. the design in the present experiment was able to eliminate this problem because an effect of attractiveness would no longer be due to greater similarity among the attractive targets.¶ method¶ participants. a different group of undergraduate students ( females and males) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to-normal vision.¶ stimuli. the attractive and unattractive face stimuli were the same as in experiments and . in addition, we also added average-looking faces. the mean ratings for the average-looking faces was . (sd = . , n = ). as in the previous experiments, each face category consisted of faces randomly selected from the respective pool of stimuli for each participant. each trial contained one attractive, one unattractive, and three average-looking target faces. the distractors in this experiment consisted of average-looking faces. because average faces were used in each trial and trials in total, this requires a total of average faces ( × ). since there were average faces available, each face was repeated about times ( ÷ = . ).¶ deleted: experiment confirmed that attractive targets could induce a stronger binding of face identity and location. finally, experiment deleted: deleted: experiment deleted: ... [ ] page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking unattractiveness advantage. from this point, the tracking advantage for attractive targets is less likely to reflect featural similarity of attractive faces. facial beauty would not produce an effect on these tracking tasks if facial features and their holistic information were not processed during the process of tracking. therefore, given the pattern of our results, the representations of the target items must be content addressable. there is already evidence that face or object identities are processed in multiple target tracking (horowitz et al., ; oksama & hyönä, ; ren et al., ). the present study shows further that facial attractiveness is also processed during tracking. as the results in experiment indicate, attractiveness appeared to be assessed only for the target items, because distractors had negligible effects on tracking performance. this finding is consistent with the observation that only target identity is processed in multiple-object or multiple-face tracking (pylyshyn, ; ren et al., ). contrary to the suggestion that multiple object tracking is purely driven by low-level vision, of which higher level cognitive processes are unable to penetrate, tracking performance appeared to be modulated by the information content of target items. content addressability may depend on whether the information is important to the observer and whether the observer is predisposed to process the type of information. like face identity, attractive faces may automatically engage the attention system. the appraisal for attractiveness in our experiments was spontaneous because it was task irrelevant. although the effects of such automatic appraisal in this and other studies (e.g., sui & liu, ) can be quite small, they are consistent and replicable. a small effect in these studies may suggest that task-irrelevant processing can be largely suppressed by the central control. the present study revealed that a participant’s tracking performance was negatively correlated with the size of attractiveness effect. this suggests that some individuals page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking may have weaker central control than others: those who were not as good at tracking showed a larger attractiveness effect because they might not have as much central control and were more easily distracted by the irrelevant information. perhaps due to the extent of the central control, not all evidence to date shows that appraisal of attractiveness is spontaneous or mandatory. schacht, werheid, and sommer ( ) found that attractiveness appraisal depended on whether facial attractiveness was task relevant (e.g., beauty rating). this led them to conclude that attractiveness appraisal requires voluntary attention to the attractiveness dimension. the findings of our study show that facial attractiveness can be appraised even when it is not task relevant. our analyses of the correlation between the effect of attractiveness and tracking performance in the three experiments provide preliminary evidence that participants with higher tracking performance tend to produce a smaller attractiveness effect. this may be due to these participants’ better central control to suppress task-irrelevant appraisal of facial attractiveness. task irrelevant processing of facial beauty has been reported in brain research. chatterjee, thomas, smith and aguirre ( ) found that the ventral occipital region remained responsive to facial beauty when the task of their participants was to judge facial identity rather than to attend explicitly to attractiveness. they proposed that this region, which includes the fusiform gyrus, the lateral occipital cortex and medially adjacent regions, is activated automatically by beauty and may serve as a neural trigger for pervasive effects of attractiveness in social interactions (see also kampe et al., ). undoubtedly, the exact level of control that the central executive can have over automatic processing of certain task-irrelevant stimuli will require systematic future research. the present study also provides preliminary evidence that target tracking is spontaneously affected by gender detection. experiment showed that male faces were tracked better than page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking female faces. this could be due to a gender bias as participants in this experiment were mainly comprised of females. when we tested equal number of male and female participants in experiment , results showed that female participants tracked the location of an attractive male face more accurately relative to an unattractive male face. however, it is unclear why the same effect was not found for female faces. the gender effect found in experiment may be similar to bayliss et al ( ), who found that averted eyes of a face or nonpredictive arrows produce a stronger reflexive shift of attention in females than in males. given that the participants in our experiments and were predominantly females, the results in these experiments could be largely driven by certain aspects of gender difference. the role of gender difference in attentive tracking is therefore an important area for future investigation. consistent with prior research, attractive face stimuli in this study were also rated more positively on the valence dimension. although valence did not contribute to the tracking advantage of attractive faces when the tracked faces had similar attractiveness (experiments and ), it did contribute to the tracking performance when the target faces consisted of a full range of attractiveness (experiment ). thus, the lack of valence effect in experiments and may be due to the much smaller range of this variable associated with the attractive targets. positive valence is a central trait of facial beauty. it is therefore not surprising that it produced a similar effect to attractiveness on distributed attention. it should be noted, however, that the differences in valence ratings of attractive and non-attractive faces were quite small. no significant difference was found in arousal ratings of attractive and non-attractive faces. these rating data may suggest a moderate link between facial attractiveness and valence, whereas the link between facial attractiveness and arousal is negligible. although it is difficult to separate attractiveness from positive valence due to the very deleted: deleted: the face gender issue is therefore still at an early stage of deleted: deleted: deleted: page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking nature of beauty, it is possible to study whether valence in other types of stimuli produces a similar effect on multiple object tracking. a similar conclusion can be made about the relationship between attractiveness and averageness. it would not be possible to separate attractiveness from averageness because averageness is a defining feature of attractiveness. however, it is possible to study whether averageness in non-face stimuli also produces a similar advantage in a multiple object tracking task. there is little evidence that averageness in other kinds of stimuli also attracts attention although it is highly likely that beautiful things in general attract more attention. unlike faces, the relationship between averageness and other types of beautiful things remains to be seen. in face research, this relationship is established through image morphing techniques. however, it is often difficult to use the same method that requires well-defined corresponding features to build an average for other categories of things such as beautiful sunsets, because obvious correspondence in such images is often absent. the attentional bias for attractive faces found in this study suggests that multiple object tracking is modulated by underlying biological significance of the tracked targets. it may reflect biological interests of the observer. the preference for attractive faces may be deeply rooted in evolution (langlois et al., ; rhodes, ). prior research has demonstrated an automatic reaction to facial beauty in focalized attention. the present study shows a similar response to beauty in distributed attention. because multiple object tracking depends on attentional resources in the working memory (oksama & hyona, ), our results may suggest higher working memory capacity and greater attentional resources for attractive faces. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking author notes this research was supported by grants from the royal society, kc wong foundation, and program ( cb ). we thank professor david perrett for offering the face stimuli, and emma medford for her thoughtful comments on an earlier version of this manuscript. we especially thank the reviewers for their constructive comments and suggestions on. deleted: the earlier versions page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking footnote we thank dr. trafton drew for suggesting this idea. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking references aharon, i., etcoff, n., ariely, d., chabris, c. f., o’connor, e., & breiter, h. c. ( ). beautiful faces have variable reward value: fmri and behavioral evidence. neuron, , – . bayliss, a. p., di pellegrino, g., & tipper, s. p. ( ). sex differences in eye gaze and symbolic cueing of attention. quarterly journal of experimental psychology, a, – . chatterjee, a., thomas, a., smith, s. e., & aguirre, g. k. ( ). the neural response to facial attractiveness. neuropsychology, , - . dion, k. k., berscheid, e., & walster, e. ( ). what is beautiful is good. journal of personality & social psychology. , – . eagly, a. h., ashmore, r. d., makhijani, m. g., & longo, l. c. ( ). what is beautiful is good, but . . .: a meta-analytic review of research on the physical attractiveness stereotype. psychological bulletin, , – . geldart, s., maurer, d., & carney, k. ( ). five-month-olds’ attention and affective responses to still-faced emotional expressions. infant behavior & development, , - . grammer, k., & thornhill, r. ( ). human (homo sapiens) facial attractiveness and sexual selection: the role of symmetry and averageness. journal of comparative psychology, , – . guo, k., liu, c. h., & roebuck, h. ( ). i know you are beautiful even without looking at you: discrimination of facial beauty in peripheral vision. perception, , - . horowitz, t. s., klieger, s. b., fencsik, d. e., yang, k. k., alvarez, g. a., & wolfe, j. m. ( ). tracking unique objects. perception & psychophysics, , – . page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking kampe, k. k. w., frith, c. d., dolan, frith, r. j., u. ( ). reward value of attractiveness and gaze. nature, , . kranz, f., & ishai, a. ( ). face perception is modulated by sexual preference. current biology , – . lang, p.j., bradley, m.m., & cuthbert, b.n. ( ). international affective picture system (iaps): affective ratings of pictures and instruction manual. technical report a- . university of florida, gainesville, fl. langlois j. h., & roggman, l. a. ( ). attractive faces are only average. psychological science, , – . langlois, j.h., roggman, l. a., casey, r. j. ritter, j. m., rieser-danner, l. a., & jenkins, v. y. ( ). infant preferences for attractive faces: rudiments of a stereotype? developmental psychology, , - . langlois, j. h., kalakanis, l. e., rubenstein, a.j., larson, a. d., hallam, m. j., & smoot, m.t. ( ). maxims or myths of beauty: a meta-analytic and theoretical review. psychological bulletin, , – . makovski, t., & jiang, y. v. ( ). feature binding in attentive tracking of distinct objects. visual cognition, , - . maner, j. k., gailliot, m. t., & dewall, c. n. ( ). adaptive attentional attunement: evidence for mating-related perceptual bias. evolution and human behavior , – . maner, j. k., gailliot, m. t., rouby, d. a., & miller, s. l. ( ). can’t take my eyes off you: attentional adhesion to mates and rivals. journal of personality and social psychology, , - . page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking oksama, l., & hyona, j. ( ). is multiple object tracking carried out automatically by an early vision mechanism independent of higher-order cognition? an individual difference approach. visual cognition, , - . oksama, l., & hyona, j. ( ). dynamic binding of identity and location information: a serial model of multiple identity tracking. cognitive psychology, , - . palermo, r, & rhodes, g. ( ). are you always on my mind? a review of how face perception and attention interact. neuropsychologia, , - . pylyshyn, z. w. ( ). some puzzling findings in multiple object tracking: i. tracking without keeping track of object identities. visual cognition, , - . pylyshyn, z. w. ( ). some puzzling findings in multiple object tracking (mot): ii. inhibition of moving nontargets. visual cognition, , - . pylyshyn, z. w., & storm, r. w. ( ). tracking multiple independent targets: evidence for a parallel tracking mechanism. spatial vision, , - . ren, d., chen, w., liu, c. h., & fu, x. ( ). identity processing in multiple-face tracking. journal of vision, ( ): , - . rhodes, g. ( ). the evolutionary psychology of facial beauty. annual review psychology, , - . rhodes, g., sumich, a., & byatt, g. ( ). are average facial configurations attractive only because of their symmetry? psychological science, , – . samuels, c. a., butterworth, g., roberts, t., graupner, l., & hole, g. ( ). facial aesthetics: babies prefer attractiveness to symmetry. perception, , - . schacht, a., werheid, k., & sommer, w. ( ). the appraisal of facial beauty is rapid but not mandatory. cognitive, affective, and behavioral neuroscience, , - . page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking slater, a., von der schulenberg, c., brown, e., bademoch, m., butterworth, g., parsons, s., & samuels, c. ( ). newborn infants prefer attractive faces. infant behavior & development, , - . sui, j., & liu, c. h. ( ). can beauty be ignored? effects of facial attractiveness on covert attention. psychonomic bulletin & review, , - . yantis, ( ). multielement visual tracking: attention and perceptual organization. cognitive psychology, , - . page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking table mean ratings of valence and arousal. values in parentheses represent standard deviation. ____________________________________________ attractiveness valence arousal ____________________________________________ attractive . ( . ) . ( . ) average . ( . ) . ( . ) unattractive . ( . ) . ( . ) ____________________________________________ page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology attractiveness affects multiple-face tracking figure captions figure . illustration of the procedure used in the study. a. procedure used in experiments and . b. procedure used in experiment . figure . tracking accuracy in experiment as a function of target and distractor attractiveness. a. results of male faces. b. results of female faces. error bars represent standard errors. figure . scatter plots for the correlation between the size of attractiveness effect and tracking performance. figure . tracking accuracy in experiment as a function of target attractiveness and face gender. error bars represent standard errors. figure . tracking accuracy in experiment as a function of target attractiveness and face gender. a. results of male faces. b. results of female faces. error bars represent standard errors. deleted: deleted: deleted: a. results of male faces. b. results of female faces. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology page : [ ] deleted unknown / / : : am experiment in both experiments and , the target faces were either attractive or unattractive. when the targets had a similar level of attractiveness, attention might be more or less evenly distributed among the targets. however, if attractiveness varies considerably among targets, attention and consequently tracking performance for a given target could be affected by its attractiveness relative to other targets. to test this hypothesis, we varied level of target attractiveness in this experiment such that the targets consisted of attractive, average, and unattractive faces. we then compared the performance for these different types of targets. another issue concerning the use of all attractive or all unattractive targets was that attractive faces may be more visually similar to one another than unattractive faces. yantis ( ) showed that similarity among targets improves tracking. because of this, the tracking advantage for attractive targets may not reflect attractiveness directly, but rather through featural similarity. the design in the present experiment was able to eliminate this problem because an effect of attractiveness would no longer be due to greater similarity among the attractive targets. method participants. a different group of undergraduate students ( females and males) from the university of hull participated in this study. the age of the participants ranged from to years (mdn = ). all participants had normal or corrected-to- normal vision. stimuli. the attractive and unattractive face stimuli were the same as in experiments and . in addition, we also added average-looking faces. the mean ratings for the page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology average-looking faces was . (sd = . , n = ). as in the previous experiments, each face category consisted of faces randomly selected from the respective pool of stimuli for each participant. each trial contained one attractive, one unattractive, and three average-looking target faces. the distractors in this experiment consisted of average-looking faces. because average faces were used in each trial and trials in total, this requires a total of average faces ( × ). since there were average faces available, each face was repeated about times ( ÷ = . ). design. this was again a within-subject design. the independent variables were target attractiveness (attractive, average, and unattractive) and face gender. procedure. this was identical to experiment . results and discussion the tracking results are shown in figure . the main effect of target attractiveness was significant, f ( , ) = . , mse = . , p < . , partial η = . . no significant effect was found for face gender, f ( , ) = . , mse = . , p = . , or interaction between face gender and target attractiveness, f ( , ) = . , mse = . , p = . . post hoc comparisons of means with bonferroni correction revealed better tracking performance for attractive targets relative to average or unattractive targets ts ( ) > . , ps < . . there was no difference between results for average and unattractive targets, t ( ) = . , p = . . the results suggest that attractive faces were attended more favourably whereas unattractive and average-looking faces were not treated differently during tracking. consistent with experiments and , there was a significant negative correlation between participants’ overall tracking performance and the size of the attractiveness page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology effect, r = - . , p < . . a scatter plot of this correlation is shown in figure c. results of ancova for experiment show that there was a significant main effect of target attractiveness, f ( , ) = . , mse = . , p < . , partial η = . , where attractive faces were tracked better than average-looking and unattractive faces (ps < . ), and there was no difference between average-looking faces and unattractive faces (p = . ). the covariate, or valence of the faces, was also significantly related to the tracking performance, f ( , ) = . , mse = . , p < . , partial η = . . this indicates that the valence of faces also contributed to the attractiveness effect in this experiment. page of url: http:/mc.manuscriptcentral.com/pqje quarterly journal of experimental psychology british medical journal volume july antacids/alginates, histamine antagonists, and sucralfate. the new design of bougie was producing good results, half the patients not needing a further dilatation for months. pancreatic cancer increasing dr mitchell showed that the frequency of pancreatic cancer was increasing: the condition was now commoner than cancer of the stomach. nevertheless, though modern methods such as computer tomography and endoscopic retrograde cholangiopancreatography were making the diagnosis more specific, patients still usually came to the clinic with advanced disease. the ideal test still had to be developed, and the best method of early diagnosis was a high index of suspicion in any patient with malaise and loss of weight. professor losowsky discussed hepatitis problems and solutions, emphasising that persistent hepatitis b infection was associated with a considerably increased risk of hepatoma. rarely remissions had occurred with treatment with interferon, but combinations of antiviral agents needed to be given. thus, though the ultimate aim must be eradication of the infection, the short term one must be to prevent transmission. patients known to be antigen positive must tell their doctor or dentist of this fact; conversely the general practitioner must give patients firm advice on lifestyle in simple lay language-yet a survey had shown that few did this. the current vaccine was expensive yet effective and boosters were required only occasionally. concluding, sir christopher booth pointed to one outstanding achievement of the nhs: the striking improvement in hospital practice. before the pickles practice in wensleydale had made it a rule never to send a patient to hospital-which was a virtual death sentence. the standard of the work at scarborough, as well as the outstanding quality of the presentations that afternoon, showed how far standards had advanced in years. "small is beautiful" in whitby christiane harris in the s emphasis was put on large district general hospitals and many small community hospitals were closed. current thinking suggests that this may have been a mistake and that perhaps "small is beautiful" after all. the scientific session at whitby hospital on june during the annual representative meeting, which was intended primarily for general practitioners, provided an oppor- tunity to further the debate on the future of general practitioner beds and general practitioner or community hospitals. it was probably unique to unite hospital, general practice, and community services in the same complex, dr d r lockstone said. he is a general practitioner in whitby and he explained that the aims of the whitby scheme (of hospital and health centre) had been to blur the edge between hospital and general practice and to improve the relationship between general practitioners and consultants. he and his colleagues were confident that these aims had been achieved. whitby hospital had received its first patients in . the original estimate of the cost of building the hospital had been £ - million-the eventual cost was £ million. fully integrated services dr lockstone showed the visitors the range of services provided. the hospital has general practitioner beds, geriatric beds, and maternity beds. the hospital services are fully integrated with a health centre comprising eight general practitioners, one trainee, a practice nurse, a practice manager and reception staff, and a dispensary. together with a branch dispensing practice at robin hood's bay the health centre caters for a population of but in the peak holiday season-july to mid-september-the population almost doubles. this results in a high proportion of temporary residents- out of a total of consultations at whitby last year. the complex also houses the school medical services, a school dentist, chiropody, speech therapy, child guidance, and community paediatric services, as well as a large physiotherapy department, which serves inpatient, outpatient, and community needs and works closely with the occupational therapy department. barium studies and intravenous pyelography are performed routinely in the x ray department. a visiting radiographer from scarborough district hospital attends once a week to do ultrasound studies using whitby's own small machine. all these facilities are available to general practitioners' patients as well as to hospital inpatients and outpatients. the films are usually interpreted by the referring doctor although the consultant radiologist comes from the district general hospital twice a week to review all new films. the casualty department has a crash room and full facilities for resuscitation. casualties are brought to whitby, regardless of the severity of their injuries, if it is the nearest department to the accident, so the staff are often called on to give initial treatment to seriously injured patients before they are transferred either to scarborough ( miles) or, in the case of head injuries or burns, to the regional centre at middlesbrough ( miles). the general practitioners who are on call for the practice and the hospital are also responsible for the casualty department. they thus shoulder a great deal ofresponsibility but between them they possess a wide range of specialist qualifications and hold clinical assistantships in accident and emergency, ophthalmology, obstetrics, orthopaedics, and ear, nose and throat. the geriatric beds are under the care of two general practitioners from other practices. visiting consultants hold out- patient clinics in most specialties. there is a consultant maternity unit, but patients needing elective caesarean sections or those considered a high obstetric risk are transferred to scarborough. despite this careful selection the unit has nearly deliveries a year, and three emergency caesarean sections were performed last year. having received such a positive view of a community hospital, more than one visitor must have asked himself why centres like whitby were so few and far between. the afternoon's speakers tried to answer this question. essential to create a "living organism" the unit general manager at cheltenham general hospital, dr c d shaw, said that attitudes towards community hospitals had varied during the past years. people were now beginning to see university college london school of medicine, london wcle bt christiane harris, bsc, medical student correspondence to: flat e, brechin place, london sw qb. o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j (c lin r e s e d ): first p u b lish e d a s . /b m j. . . o n ju ly . d o w n lo a d e d fro m http://www.bmj.com/ advantages in small, decentralised hospitals. it was appropriate that some definition of a general practitioner hospital should be attempted. technically, the term applied only to those hospitals with more than half general practitioner beds but this definition would exclude a site like whitby, which clearly had all the characteristics of a hospital where a general practitioner could treat his own patient under his own direct care in a hospital. in his view the advantages of a community/general practitioner hospital were the ease of access, the cheapness, and the general pressure to return to primary health care. dr shaw went on to explain which factors were essential to ensure the viability of a community hospital (figure). the "body" was important but it was the "legs" which made it a "living organism." clinics dy maternity anaesthetics inpatients casualty radiology surgery factors essential for the viability of a community hospital. the problem was that there had been a tendency for health authorities to amputate selectively the legs until they were left with an organism which would not move at all-that is, a repository for patients with long term, chronic problems. the major problem facing community hospitals, dr shaw said, was that the government did not have a consistent policy. con- sultant beds were planned for while general practitioner beds seemed to be tolerated; there was a feeling that each general practitioner bed was competing with a consultant bed. so it was important to judge these beds in terms of their use rather than in terms of who cared for their occupants and to cultivate a flexible relation between general practitioners and consultants such as existed at whitby. another problem was that a small hospital was always at risk when health authorities had to make cuts because the running costs british medical journal volume july were a discrete figure on the annual budget sheets and a closure was an easy way of making a substantial saving at a stroke rather than closing one or two wards at a district general hospital. community hospitals would survive, dr shaw told his audience, but only if general practitioners and consultants took the lead in supporting them. importance of job satisfaction dr r h jones, a senior lecturer in primary medical care at the university of southampton, had worked in a general practitioner hospital. he listed the advantages as follows: an improved relation- ship between primary and secondary care; an improved relationship between general practitioners and postgraduate education centres; continuity of care; improved relationship with lay and paramedical staff; and job satisfaction. dr lockstone confirmed the last advantage as being the single most important factor for the whitby doctors. how often do patients really need to be admitted to a district general hospital, dr jones asked. studies in oxford had suggested that - % of acute medical patients were under general practi- tioner care and in brecon the figure was as high as %. the indications were that - % of all admissions to district general hospitals were for conditions that could be treated in the general practitioner hospital. many studies, he said, had concentrated on the hazards of admission to large hospitals and it seemed probable that the risks of iatrogenic disease could be less in a community hospital although there was little evidence for this view yet. a recently published survey of the community health programme in oxfordshire had shown that one third of general practitioners had access to beds in general practitioner hospitals as well as in district general hospitals when these practices were compared with those without access it was found that the rate of use of acute medical and geriatric beds in district general hospitals in the former group was only half that of the latter and that total bed utilisation (acute medical and geriatric beds in general practitioner hospital and district general hospital combined) was slightly higher in the latter group. the future for community/general practitioner hospitals throughout the country is hard to predict. what was clear was that a scheme such as the one at whitby not only works but receives the full support of everyone associated with it. one of the whitby general practitioners, dr david thomas, told us that if he should ever collapse and be in need of resuscitation he knew of no one he would rather have treat him than one of his colleagues at whitby hospital. what greater vote of confidence could the scheme possibly hope for? council meeting in scarborough the first council meeting of the - session was held in scarborough at the conclusion ofthe arm. the chairman, dr john marks, welcomed the new members of council and thanked those members who were no longer on the council. the following members were elected to the finance and general purposes committee: dr w e dixon, dr j m dunlop, dr p f kielty, dr e b lewis, dr caroline marriott, dr j a riddell, mra p j ross, and drma wilson. transmission of prescriptions to the ppa the following guidance is intended for dispensing doctors for transmitting prescription forms to the prescription pricing authority (ppa). it has been prepared by the rural practices subcommittee of the general medical services committee and the ppa. "( ) if there is more than one doctor in a practice all forms should be submitted in one parcel. however, if the doctors require individual payment the parcel should be subdivided into bundles relating to each doctor and the details recorded separately on a single parcel invoice. "( ) ideally, prescribers should use only their own prescription pads. "( ) form fp d should be complete as re- quired. particular care should be taken in carrying out the appropriate deletion regarding vat. "( ) each doctor's name and index number should be entered along with the number of forms and items. "( ) all doctors' forms and the completed fp d should then be parcelled up securely and posted to the ppa using the labels supplied by the family practitioner committee. 'securely' is defined as tying the bundle firmly, placing it in a plastic bag, and either wrapping in strong paper or placing it in a suitably sized box. "( ) the green address labels, obtainable from the family practitioner committee, should be used on the outside of the parcel. "( ) a certificate ofposting or recorded delivery is an extra security in the event of a query from the ppa regarding the non-arrival of the parcel." doctors in independent hospitals guidance for resident medical officers in private hospitals in the form ofa model job description and a model contract is available to bma members from the bma secretariat and from regional offices. details of the guidance were published on may (p ). it was prepared by the inde- pendent medical practice subcommittee of the central committee for hospital medical services and the joint consultants committee and was agreed with the association of independent hos- pitals and the independent hospitals group. published by the proprietors, the british medical association, tavistock square, london wc h jr, and printed in great britain by pulman web offset limited, member of the bpcc group. typesetting by bedford typesetters limited, bedford. registered as a newspaper. o n a p ril b y g u e st. p ro te cte d b y co p yrig h t. h ttp ://w w w .b m j.co m / b r m e d j (c lin r e s e d ): first p u b lish e d a s . /b m j. . . o n ju ly . d o w n lo a d e d fro m http://www.bmj.com/ () science china information sciences february , vol. : – : https://doi.org/ . /s - - - c© science china press and springer-verlag gmbh germany, part of springer nature info.scichina.com link.springer.com . letter . special focus on deep learning for computer vision multi-attention based cross-domain beauty product image retrieval zhihui wang, xing liu, jiawen lin, caifei yang & haojie li* international school of information science and engineering, dalian university of technology, dalian , china received july /revised october /accepted november /published online january citation wang z h, liu x, lin j w, et al. multi-attention based cross-domain beauty product image retrieval. sci china inf sci, , ( ): , https://doi.org/ . /s - - - dear editor, in recent years, the perfect half million beauty product image recognition challenge has been held by acm multimedia [ ] for beauty prod- uct image retrieval task, and the perfect- k dataset has been released, acting as a large-scale beauty product dataset. retrieval methods ex- ploit classic cnn models to extract features and conduct either fusion or post-process to enhance accuracy of feature description (e.g., [ – ]). oth- ers are inclined to design network architecture to achieve the idential effect (e.g., [ – ]). by observ- ing the dataset, we argue that the beauty product objects are conspicuous and the text regions of im- ages display noticeable discrimination. to concentrate on the salient objective area, as well as the the prominent text content, we propose an end-to-end multi-attention classification net- work manet, accounting for the basic feature ex- traction. besides, a saliency-based regional max- imum activation of convolutions (sr-mac) mod- ule for feature representation is proposed to re- duce the effect of background regions unrelated to the salient region on manet’s convolution activa- tion and to increase the feature weight of regions related to the salient region; it is capable of ob- jectively aggregating multiple local features and making the feature representation of beauty prod- uct images more discriminative. besides, word frequency statistics of the text description of each image in perfect- k is an- alyzed using the tf-idf algorithm and cate- gories are roughly counted. subsequently, some images are extracted from perfect- k dataset associated with these categories and a well- labeled “few-shot” dataset is built, named perfect- k. the proposed method for beauty product im- age retrieval is illustrated in figure , consisting of the offline part and the online part. given a query image online, we use manet to extract the basic feature tensor, and sr-mac is employed to aggregate local features from it. after post-process with l normalization, final features are obtained for the query. multi-attention classification network. the pro- posed manet has three branches and employs a full convolution structure: it is composed of the saliency attention mechanism, the backbone net- work, as well as the text attention mechanism. be- cause various branches have different tasks, differ- ent network structures are designed. saliency attention mechanism. the saliency attention mechanism in manet covers the “up- to-down” and “down-to-up” processes of feature learning. the “up-to-down” process learns the high-level semantic information of images, which is capable of finding the location of salient regions but at the expense of the loss of details. besides, the “down-to-up” process merges a wide range of outputs, so the most visually distinctive objects can be extracted. during the training phase, the pseudo-saliency mask is adopted to fine-tune the saliency branch * corresponding author (email: hjli@dlut.edu.cn) http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf&date_stamp= - - https://doi.org/ . /s - - - info.scichina.com link.springer.com https://doi.org/ . /s - - - https://doi.org/ . /s - - - wang z h, et al. sci china inf sci february vol. : query image sr-mac l manet salienct region feature extraction weighted feature online feature extraction …… offline dataset query feature rank list rerank … p o o li n g saliency attention branch text attention branch figure (color online) method overview. the whole framework includes two parts: the offline part and the online part. network. the region with values greater than the mean value of saliency mask in the pseudo-saliency mask is treated as the product object region. the value below the mean in the mask is set to ; oth- erwise, it is set to . the network is trained by minimizing the following loss function: ls = − n∑ i= |f(xi, Θ) ⋂ yi| |f(xi, Θ)| + |yi| , ( ) where x = {xi} n i= denotes the set of training images, and {yi} n i= denotes pseudo-saliency mask corresponding to the training images. all the pa- rameters of saliency branch network are defined as Θ. f refers to the saliency attention model. text attention mechanism. to draw upon text information, text attention mechanism is adopted to make the network notice the features of the text regions in the learning process. east [ ] refers to a powerful pipeline that yields fast and accurate text detection; thus the text mask output from it is directly adopted as the output of the branch. besides, the text mask is adjusted by ( ) to retain the weighting effect of saliency attention branch on backbone network feature tensor: t = sigmoid(tm) + , ( ) where tm refers to the text mask and t is the ad- justed text mask. the feature x of backbone net- work’s last convolution layer after being weighted by saliency attention corresponding to channel k with the spatial location of (i, j) is expressed as xkij, and the adjusted text mask t with location of (i, j) is denoted by tij. the final weighted fea- ture tensor x̃ is produced using the text attention mechanism as written in x̃k = tij ⊗ xkij, ( ) where ⊗ represents element-wise multiplication. the text mask generated by east is applied to weight our feature map because training text detection requires text region annotation, which is beyond the scope of our research. so in order to avoid extra supervised information of text re- gion, text attention branch does not participate in our training, whose parameters are frozen, and we update the parameters of backbone network and saliency attention branch only. sr-mac feature representation. the global fea- ture from manet expresses the overall information of the image, with no discriminative details. to aggregate the local features and obtain discrimi- native features of the beauty product images, an sr-mac module is proposed. besides, the feature of backbone network’s last convolutional layer is weighted by saliency attention and text attention is acted as the basic feature tensor to extract local features. in accordance with r-mac [ ] method, we obtain convolution responses xr = {x , . . . , xr, . . . , xm} corresponding to m re- gions. we define the regional feature vector: x r = [fr , . . . , f r i , . . . , f r k], ( ) where fri = max(c r i ) denotes the maximum acti- vation of the ith channel on the considered region r. moreover, these local regions are defined on the space Ω of all valid positions for the considered feature map (and not on the input image plane). our proposed sr-mac uses the saliency atten- tion mechanism to assign different weights to re- spective regions. the local region weight is calcu- lated as follows: wr = r ⋂ s r , ( ) wang z h, et al. sci china inf sci february vol. : where r denotes the local region, and s indicates the saliency region. the weighted feature of the local region r is calculated as follows: x́ r = wr · [f r , . . . , f r i , . . . , f r k]. ( ) the final sr-mac feature is represented as fol- lows: Φ = [f́ , . . . , f́i, . . . , f́k], f́i = m∑ r= norm(f́ri ),( ) where f́ri = wr · f r i . experiments. in this study, tf-idf algorithm is applied to analyze word frequency statistics of all text descriptions appearing in perfect- k dataset and rough categories are counted. se- quentially, approximately images are ex- tracted from perfect- k dataset associated with the categories based on the category keywords, and a “few-shot” dataset is built, named perfect- k. these categories include lipstick, sun- screen, razor, mask, each of which contains nearly images. lastly, the perfect- k dataset is split into a train dataset and a validation dataset ac- cording to the ratio of : . compared with ra-mac [ ], mff [ ], and pre- trained resnet [ ], which are competitors of half million beauty product image recognition challenge , our proposed manet achieves the optimal result on perfect- k with . map@ , which is higher than those of ra-mac with . map@ , mff with . map@ , and pre-trained resnet with . map@ , respec- tively. the advantages of this study are interpreted as follows: ( ) saliency and text attention mechanism are used to make manet pay more attention to the product objects and the text regions in the im- ages; ( ) a robust local feature aggregation method is proposed, eliminating the interference of back- ground information and retaining the key local ar- eas in the product object region by using saliency mechanism; ( ) a well-labeled beauty product im- age dataset is built, and the network is trained on it to learn more accurate feature description for beauty products. for more detailed experimental results, please refer to the supplement materials. conclusion. an end-to-end multi-attention classification network manet for beauty product images retrieval is proposed, focusing on the fea- tures of saliency regions and text regions in the images and suppressing the interference of irrele- vant information. to take the details of beauty product images, an sr-mac feature representa- tion module is proposed. the feature obtained by sr-mac eliminates the interference of object- independent region in manet’s convolution acti- vation and enhances the feature weight of regions related to the salient region. besides, a “few-shot” beauty product dataset, perfect- k, with cat- egories for training our proposed manet is con- structed. the retrieval performance of our method on the perfect- k dataset outperforms the state- of-the-art methods, which indicates the effective- ness of our method. acknowledgements this work was supported in part by national natural science foundation of china (grant nos. , , ). supporting information experiments. the support- ing information is available online at info.scichina.com and link.springer.com. the supporting materials are published as submitted, without typesetting or editing. the respon- sibility for scientific accuracy and content remains entirely with the authors. references cheng w-h, jia j, huang j. half million beauty prod- uct image recognition. . https://challenge . perfectcorp.com/ lin z, yang z, huang f, et al. regional maximum activations of convolutions with attention for cross- domain beauty and personal care product retrieval. in: proceedings of acm conference on multimedia, . – wang q, lai j x, xu k, et al. beauty product im- age retrieval based on multi-feature fusion and feature aggregation. in: proceedings of acm conference on multimedia, . – lim j h, japar n, ng c c, et al. unprecedented usage of pre-trained cnns on beauty product. in: proceed- ings of acm conference on multimedia, . – sun h q, pang y w. glancenets–efficient convolu- tional neural networks with adaptive hard example mining. sci china inf sci, , : zhong j, sun y x, yu y l, et al. attribute- guided network for cross-modal zero-shot hashing. ieee trans neural netw learn syst, . doi: . /tnnls. . li h j, wang x h, tang j h, et al. combining global and local matching of multiple features for precise item image retrieval. multimedia syst, , : – zhou x, yao c, wen h, et al. east: an efficient and accurate scene text detector. in: proceedings of the ieee conference on computer vision and pattern recognition, . – tolias g, sicre r, jegou h. particular object re- trieval with integral max-pooling of cnn activations. in: proceedings of the th international conference on learning representations, san juan, info.scichina.com link.springer.com https://doi.org/ . /s - - - https://doi.org/ . /s - - - december , ucb-pth- / slac-pub- hep-ph/ atmospheric neutrinos can make beauty strange∗ roni harnik, daniel t. larson and hitoshi murayama theoretical physics group ernest orlando lawrence berkeley national laboratory university of california, berkeley, california , usa department of physics, university of california berkeley, california , usa aaron pierce theoretical physics group stanford linear accelerator center stanford university, stanford, california, , usa abstract the large observed mixing angle in atmospheric neutrinos, coupled with grand unification, motivates the search for a large mixing be- tween right-handed strange and bottom quarks. such mixing does not appear in the standard ckm phenomenology, but may induce signifi- cant b → s transitions through gluino diagrams. working in the mass eigenbasis, we show quantitatively that an o( ) effect on cp violation in b d → φks is possible due to a large mixing between s̃r and b̃r, while still satisfying constraints from b → sγ. we also include the effect of b̃l-b̃r mixing proportional to mbµ tan β. in the case where mbµ tan β � m susy there may be a large effect in bs mixing corre- lated with a large effect in b d → φks, typically ∆mbs >∼ ps− , an unambiguous signal of new physics at tevatron run ii. ∗the work of rh, dl, and hm was supported in part by the u.s. department of energy under contract de-ac - sf , and in part by the national science foundation under grant phy- . the work of ap was supported by the u.s. department of energy under contract de-ac - sf introduction flavor physics has seen tremendous progress in the past few years. the discovery of neutrino oscillations by the superkamiokande [ ], sno [ ], and kamland [ ] experiments clearly marks a historic event, while cp violation has recently been found in two new manifestations: direct cp violation in the neutral kaon system [ ] and indirect cp violation in the the b d system [ ]. on the other hand, we still lack insight into the origin of flavor and the patterns of masses and mixings. we need to look for any possible hints of physics that give us additional insight into these questions. one of the major surprises in neutrino physics was the observation of (two) large angles. unlike in the quark sector where all mixing angles in the cabibbo–kobayashi–maskawa (ckm) matrix are small, both atmospheric and solar neutrino oscillations require large angles. an important question is whether the presence of large angles will give us new insight into the origin of flavor, masses, and mixings. it was pointed out in ref. [ ] that the large angles in the neutrino sector may imply large angles in the mixing among right-handed down-type quarks if they are grand-unified with lepton doublets. indeed, some so( ) models with pati–salam type unification of yukawa matrices suggest that the large mixing angles in neutrinos arise from the charged lepton mass matrices, and thus also appear in the down-quark mass matrices. in these models, one assumes that these new large mixing angles do not appear in the ckm ma- trix because the right-handed charged-current interaction is broken at the pati-salam unification scale. however, the imprint of the large atmospheric neutrino mixing angle may appear in the squark mass matrices as a large b̃r-s̃r mixing effect though radiative corrections due to the large top yukawa coupling. the large solar neutrino mixing angle, however, does not cause a significant effect because of the smaller yukawa coupling for lower genera- tions. the new b̃r-s̃r mixing in turn feeds into new effects in b-physics. in particular, there may be large new cp-violating effects in b → s transitions and enhanced bs mixing. it has already been noted that cp violation in b d → φks is a good place to look for new physics effects [ , ]. the time-dependent asymmetry in b d(b d) → φks was reported recently by both babar and belle. their measurements differ from the value in the j/ψks final state by o( ). the standard model predicts that these two channels should give the same value. the significance of the difference is . σ if the measurements from both collaborations are combined– the current world average for sin β in the b d → j/ψks channel is . ± . , while in the b d → φks channel sφk = − . ± . [ ]. this report has already sparked many speculations [ ]. it is not clear if this is a temporary anomaly or a genuine new effect. nonetheless it is important to study how large the new cp violation in b d → φks can be and how it is correlated to bs mixing which will be studied soon at tevatron run ii. in this paper, we investigate the size of cp violation in b d → φks as well as bs mixing from a potentially large b̃r-s̃r mixing. there have also been several investigations of b d → φks within the context of supersymmetry (susy) [ , , ]. of the above, only ref. [ ] investigated the correlation between the measurement of sin β in b d → φks and bs mixing. however it uses the mass insertion formalism, which is not necessarily appropriate for the large mixing that we will consider. in addition, it appeared before the recent experimental results, and so it did not seek to reproduce such a large shift in sin β. we perform a calculation in the mass eigenbasis, with a goal of determining whether supersymmetry can accommodate the central value of the recent experimental results for sin β in b d → φks. we then explore the consequences for bs mixing. we also emphasize contributions to sin β that arise from a combination of b̃l-b̃r (mbµtanβ) and b̃r-s̃r mixing. these contributions, which we find to be important over a wide region of parameter space, are not easily analyzed in the mass insertion approximation. analogous combinations were studied in the kaon system [ ], but to our knowledge these contributions have not been thoroughly analyzed with regard to new physics in the b d system. the outline of the paper is as follows. in the next section we introduce the effective field theory formalism for b decay and work out b → s transitions. in section we discuss bs mixing from large b̃r-s̃r mixing. section is devoted to the discussion of correlations between the b → s transition and bs mixing. we conclude in section . details of some calculations are presented in the appendices. in appendix a we show the loop functions, while the hadronic matrix elements are estimated in appendix b. cp violation in b → s transition in this section we briefly review the well-known effective field theory formal- ism for b-physics (for a comprehensive review see [ ]), which we use to calculate the contribution of supersymmetric particles to b → s transitions. using this machinery we discuss the contribution of a large mixing between right-handed squarks to the cp-violating parameter sφk. we also use this formalism to address the constraints on the susy contribution that come from the b → sγ radiative decay. . effective hamiltonian the b → s transitions of interest can be described by the following ∆b = effective hamiltonian: heff = ∑ i= (cioi + c′io′i) + cγoγ + c′γo′γ + cgog + c′go′g, ( ) where o = (s̄iγµplcj)(c̄jγµplbi) ( ) o = (s̄γµplc)(c̄γµplb) ( ) o = (s̄γµplb)(s̄γµpls) ( ) o = (s̄iγµplbj)(s̄jγµplsi) ( ) o = (s̄γµplb)(s̄γµprs) ( ) o = (s̄iγµplbj)(s̄jγµprsi) ( ) oγ = e π mb(s̄iσ µνprbi)fµν ( ) og = gs π mb(s̄iσ µνtaijprbj)g a µν. ( ) here i and j are color indices (suppressed in color singlet terms), pr,l = ( ± γ )/ , and σ µν = i [γµ,γν]. the primed operators, which are not generated at leading order in the standard model, are obtained by taking l ↔ r everywhere. here we have ignored the electroweak penguin operators o − and the contributions to the dipole operators proportional to the s-quark mass, ms. following the standard procedure for incorporating qcd corrections we match the wilson coefficients at a high scale to loop diagrams containing heavy particles present in the full theory, and then use the renormalization group equations (rge) to run the coefficients to the low scale where mesons decay. we incorporate leading order qcd corrections using the anomalous dimension matrices given in [ ]. the initial conditions for the standard br g ~ g ~ sr br ~ s s s s r,l r,l r,l r ~ ~ δ d ( )rr _ b b r r ~ sr ~ s s s s r,l r,l r r ~ (δ )rr d _ b srr ~~ b b l r sr δ d ( )rr mb g b b l ~ sr r ~ ~ bl sr δ d ( )rr tanβµmb m~g g figure : box and penguin contributions to the b → ss̄s transition. the bottom row shows contributions to the chromo-dipole operator. we show the mass insertions for pedagogical purposes but perform calculations in the mass eigenbasis. model coefficients are also in [ ]; only c , cγ and cg are nonzero at leading order. leading order running of the standard model coefficients has mixing between all eight operators, o − ,γ,g, due to the presence of a tree level contribution to o . since right-handed squark mixing only contributes to the primed operators and gives no tree level contributions, the leading order susy running is simpler: o′ − mix only amongst themselves, as do o′γ,g. the susy contributions come from box, penguin, and dipole diagrams. figure shows sample diagrams with mass insertions schematically indicat- ing the mixing. however, since we are allowing for large mixing between the nd and rd generation squarks, we use the mass eigenbasis for our compu- tations. furthermore, we find that the region where the effect on sφk in the b d → φks channel is maximized is a region where the squarks are highly non-degenerate, again calling into question the validity of the mass insertion approximation. the squark mass matrix we consider is motivated by models where a large right-right mixing between the second and third generations is expected, such indeed, our results differ somewhat from previous investigations done in the mass insertion approximation, e.g. [ ]. as in [ ] where this mixing is related to the large mixing in atmospheric neutrinos. in addition to this new contribution we must include other off- diagonal terms that already exist in the minimal supersymmetric standard model (mssm), namely q̃rq̃l couplings induced by the cross term between the yukawa couplings and the µ term. of the down type squarks only the third generation can have appreciable left-right mixing, which is proportional to mbµtanβ. thus the mass matrix takes the approximate form m̃ d̃ =   m̃ ld m̃ ls m̃ lb mbµtanβ m̃ rd m̃ rs m̃ rsb mbµ ∗ tanβ m̃∗ rsb m̃ rb   . ( ) we define the mass eigenvalues and mixing matrices as follows: u†m̃ d̃ u = diag(m̃ l ,m̃ l ,m̃ l ,m̃ r ,m̃ r ,m̃ r ), ( ) where u is a unitary rotation matrix. without loss of generality we assume that m̃r ≤ m̃r (we allow an arbitrary mixing angle). in the mass eigenbasis × mixing matrices, Γl,r, appear in the quark-squark-gluino vertices. they are related to u by uaa = ( Γl∗ia Γr∗ia ) , ( ) where i = d,s,b labels the gauge eigenstates, a = , . . . , labels the mass eigenstates, and the index a labels states in the basis (dl sl bl dr sr br). to investigate the effect of nd and rd generation mixing of the right-handed squarks we parameterize the mixing matrix as follows: u = Φ(φ , φ )r (θ )r (θ )r (θ ), ( ) where Φ = diag( , , , ,eiφ ,eiφ ) is a phase matrix, and rij(θij) is a × rotation in the ij plane. the angle θ can be solved for using our assumption that there is no mixing between b̃l and s̃r. the wilson coefficients in the for simplicity we ignore terms that may arise from trilinear soft terms. mass eigenbasis were previously given in [ , ]. we reproduce them here, correcting two typographical errors. c′ = α s m g̃ (∑ ab Γr∗saΓ r baΓ r∗ sbΓ r sb [ − b (xa,xb) − b (xa,xb) ] + ∑ a Γr∗saΓ r ba [ − c (xa) + c (xa) ]) ( ) c′ = α s m g̃ (∑ ab Γr∗saΓ r baΓ r∗ sbΓ r sb [ − b (xa,xb) + b (xa,xb) ] + ∑ a Γr∗saΓ r ba [ c (xa) − c (xa) ]) ( ) c′ = α s m g̃ (∑ ab Γr∗saΓ r baΓ l∗ sbΓ l sb [ b (xa,xb) + b (xa,xb) ] + ∑ a Γr∗saΓ r ba [ − c (xa) + c (xa) ]) ( ) c′ = α s m g̃ (∑ ab Γr∗saΓ r baΓ l∗ sbΓ l sb [ − b (xa,xb) + b (xa,xb) ] + ∑ a Γr∗saΓ r ba [ c (xa) − c (xa) ]) ( ) c′γ = αsπ m g̃ (∑ a Γr∗saΓ r ba [ − d (xa) ] + mg̃ mb ∑ a Γr∗saΓ l ba [ − d (xa) ]) ( ) c′g = αsπ m g̃ (∑ a Γr∗saΓ r ba [ − d (xa) + d (xa) ] + mg̃ mb ∑ a Γr∗saΓ l ba [ − d (xa) + d (xa) ]) . ( ) here we use the definition xa = m̃ a/m g̃, where mg̃ is the gluino mass. the loop functions are given in appendix a. note that the contributions due to left-right mixing only enter the dipole operators c′γ and c ′ g where they are enhanced by a factor of mg̃/mb over the right-right mixing contributions to the same operators. also notice that with our choice of the mixing matrix, u, the mass eigenvalues m̃l and m̃r do not enter the wilson coefficients. because there was some disagreement in the literature, we have explicitly recomputed the box contributions (proportional to b and b ). however, the penguin contributions (proportional to c , and d − ) are well established. see for example, [ ]. we found several inconsistencies in the literature which can be remedied as follows. in equation (a. ) of [ ] the coefficient − nc of b should be replaced by − nc and the expression for c̃ dm r in equation (a. ) should be multiplied by − i . in equation ( ) of [ ] the factor of should be , and in equation ( ) the factor of should be . the loop function m (x) in [ ] should be multiplied by −x instead of − x. finally, in [ ] there are typos in each line of equations (b. a-e) and in (b. a,b). . b d → φks we now specialize our discussion to the b d → φks decay, with the goal of computing the contribution to the cp asymmetry measured in this chan- nel. in addition to the wilson coefficients we have presented, we must also compute the hadronic matrix elements of the operators. the calculation of these matrix elements is non-perturbative, so approximations must be made in order for us to make progress. in the naive factorization approximation we break each matrix element up into a pair of color singlet currents, one which creates the φ from the vacuum and the other that mediates the b d → k decay, and we discard any color-octet currents. for the operators o(′) − there are two ways of contracting the external quarks with the quark fields in the operator. after employing fierz trans- formations as necessary, and using the identity δijδk� = n δi�δkj + t a i�t a kj to rearrange color indices to form singlet currents, we arrive at the following matrix elements [ ]: 〈φks|o , |b̄ d〉 = h ( + nc ) ( ) 〈φks|o |b̄ d〉 = h ( ) 〈φks|o |b̄ d〉 = h nc ( ) where h = (,φ·pb)fφm φf+(m φ) (see appendix b for definitions of the decay constant and form factors). the same results hold for the matrix elements of the corresponding primed operators because the axial vector currents do not contribute, so the chirality of the operators is irrelevant. we take nc = throughout our analysis. the matrix elements of the chromo-dipole operators o(′)g are more difficult to analyze, so we show the details explicitly in appendix b following [ ]. these manipulations yield 〈φks|og |b̄ d〉 = κ αs π h n c − n c . ( ) where our definition of κ agrees with [ ] up to a sign convention. nu- merically we find κ = − + o ( m φ m b ) � − . . however, there were many assumptions about the quark momenta that go into this estimation of κ, so the numerical value of − . should be taken as a guideline only. we will present our results for various values of κ to demonstrate the dependence. there is one final ingredient in the standard model contribution to the amplitude. this comes from the one-loop matrix element of o when the charm quarks are closed into a loop. it is given by [ ] p = αs π c ( + g(mc,µ,q )) with g(m,µ,q ) = ∫ dxx( − x) ln m − x( − x)q µ . ( ) numerically we use mc = . gev and q = m b which gives p = (− . − . i)c . putting the factorized matrix elements together the amplitude for b̄d → φks can be written āsmφk = h [ ( + nc ) (c + c ) + c + nc c ] + h [ p + κ αs π n c − n c cg ] ( ) āsusyφk = h [ ( + nc ) (c′ + c ′ ) + c′ + nc c′ ] + h [ κ αs π n c − n c c′g ] ( ) note that in [ ] the overall factor of in the first line of equation ( ) should not be multiplying the last term that contains κdm. the time-dependent cp-asymmetry is given by aφk(t) = cφk cos(∆mb d t) + sφk sin(∆mb d t), ( ) where cφk = − |λ| + |λ| , sφk = imλ + |λ| . ( ) here λ is defined as λ = q p a(b̄ d → φks) a(b d → φks) = q p (āsmφk + āsusyφk ) (asmφk + asusyφk ) . ( ) the ratio q/p from b d mixing is dominated by the standard model and is nearly a pure phase, ei β, where β is the standard angle of the unitarity triangle. in the standard model the ratio of amplitudes ā/a is real, i.e. there is no cp violation in the decay, rather all cp violation results from mixing. on the other hand, o( ) phases in the supersymmetric contribution can give the ratio a phase, φsusy. then we have λ = ei( β+φ susy) |ā| |a| ⇒ sφk = sin( β + φ susy). ( ) thus the presence of a phase in the down squark mixing matrix can alter the measured value of sφk from the standard model prediction of sφk = sin βj/ψk = . . the amount of deviation is described in section ( . ). also note that p possesses a strong phase that is not present in asusy. the presence of a weak phase in asusy then allows for the possibility of nonzero direct cp-violation, namely cφk �= . we do not pursue this sig- nature further here, as quantitative statements are difficult due to the large hadronic uncertainties. . constraints from b → sγ a large mixing between right-handed strange and bottom squarks generates the operator o′γ through penguin diagrams, as in figure . therefore the tight experimental constraints on the branching ratio br(b → xsγ) serve to limit the contributions from squark mixing. in the model we consider there are two important contributions to the o′γ operator. we can classify the contributions according to where the helicity b s r r~ ~ b b r l sr γδd ( )rr mb b b l ~ sr r ~ ~ bl sr δ d ( )rr γ m~g tanβµmb figure : sample contributions to the b → sγ transition. we show the mass insertions here for pedagogical purposes, but perform calculations in the mass eigenbasis. flip for o′γ arises. in the first contribution, the helicity flip is present on the external b-quark line, and gives a contribution proportional to the b-mass. this contribution is present even when the only mixing between the squarks is an off-diagonal mixing between the right-handed squarks of the second and third generation. the constraint on this contribution is relatively mild. the second contribution has a helicity flip on the gluino line, so is enhanced relative to the first contribution by a factor of mg̃/mb (see equations ( ) and ( )). this contribution is only present if there is left-right mixing in the squark matrix. because of the mg̃/mb enhancement, this contribution is relatively strongly constrained. in our framework, this contribution arises only from the combination of a left-right mixing between the b̃ squarks and the right-right mixing between the b̃ and s̃ squarks. the result is that for large values of µtanβ, a smaller b̃r-s̃r mixing is allowed. when there is no significant off-diagonal mixing among the left-handed squarks, we can write: br(b → sγ) ∝ |cγ| + |c′γ| , where the first contri- bution is from the standard model and the second is from supersymmetric penguins. a recent theoretical evaluation within the standard model gives [ ]: br(b → sγ)th = ( . ± . ) × − . ( ) after rescaling to limit the photon energies to eγ > . gev (for details see [ ]), an averaging of experimental results from babar, belle, cleo, and we note that the limits of reference [ ] assume that new contributions to b → sγ are summed incoherently. in general, this will underestimate the contribution of the ll mass insertion. the two contributions are added incoherently because they contribute to different final helicity states of the s-quark. aleph [ ] yields br(b → sγ)exp = ( . ± . ) × − . ( ) the experimentally measured branching ratio is actually slightly smaller than the standard model prediction, which leaves little room for new physics con- tributions. subtracting experiment from theory we find: br(b → sγ)th −br(b → sγ)exp = (. ± . ) × − . ( ) we will require that the supersymmetric contribution keep the theoretical prediction within σ of the experimentally measured value. this means ad- ditional contributions from supersymmetry can be roughly / of those in the standard model. for simplicity, and to avoid the theoretical uncertainty associated with the direct calculation of the branching ratio, we will con- strain the supersymmetric contributions by requiring |c′γ| ≤ . × |cγ| where both coefficients are calculated to leading order. thus we are making the simplifying assumption that the higher order qcd corrections affect the two operators in the same way. . numerical analysis within the framework we have chosen, motivated by atmospheric neutrino oscillations, there are four mass eigenvalues, two mixing angles, and two phases in the down-squark mass matrix that enter in the computations of sφk and br(b → sγ). however, the fact that the neutron electric dipole moment (edm) has not been observed strongly constrains the phase of µ, especially for large µtanβ. we have checked that allowing a non-zero phase of µdoes not substantially affect even our quantitative conclusions. therefore we conservatively take the phase of µ to be zero for the remainder of this paper. including the gluino mass we are then left with eight essentially unknown parameters. in order to reduce the size of the parameter space we will investigate two limiting cases: the case where the (flavor-diagonal) mixing between left- and right-handed b̃ squarks is negligible and the case where such mixing, when coupled with the large right-right mixing, leads to the dominant contribution. we refer to the latter case as “lr+rr mixing.” note that by taking µ to be real, the remaining phase only appears as an overall phase in Γr. as a result, all susy diagrams have the same phase. . . dominant right-right mixing first we consider the situation where the contribution from b̃l-b̃r mixing is negligible, i.e. mbµtanβ � m̃ , the mass scale of the squarks. here the parameter space is reduced: in this limit there is only one mixing angle, one phase, and three mass eigenvalues that enter the computation of the wilson coefficients. the presence of mixing with an order one phase in the right-handed down squark sector can significantly alter the measured value of sφk. our first question is whether a large right-right mixing between the down squarks can reproduce the central value for sin β in the φks channel measured at the b-factories. we find that using the central value of our estimate for κ = − . , it is difficult to reproduce the observed central value and accommodate the constraints from b → sγ. however, this estimate for κ is highly uncertain, and increasing the magnitude of κ increases the contribution to sφk without changing the contribution to b → sγ. therefore, we present our numerical results for two cases, κ = − . , and a value with greater magnitude, κ = − , which we still view as reasonable given the substantial uncertainties involved in its estimation. in figure we show contours of sφk as a function of the gluino mass and m̃r . we have also chosen values for the mixing angle and phase in Γ r which give the greatest deviation of sφk from the standard model prediction. also shown are contours of the percent increase in br(b → sγ) due to new physics and the corresponding values of ∆mbs (the latter will be discussed in section ). generally speaking, lighter squark and gluino masses increase the effect of the new physics contributions, allowing sφk to depart from the standard model expectation. but at the same time this increases the contribution to br(b → sγ) and runs up against the experimental constraint. in figure we plot the same contours as a function of the gluino mass and the heavier squark mass m̃r , with m̃r = gev. for κ = − . there is a range of gluino masses where sφk can be below zero while the increase in br(b → sγ) is less than %. the minimum possible sφk allowed by this constraint decreases as the magnitude of κ increases. finally in figure we plot the same contours as a function of the gluino within the mssm µ tanβ cannot go to zero while satisfying experimental constraints. we find, however, that there is a portion of parameter space above the smallest exper- imentally allowed value of µ tanβ where the right-right mixing diagrams are dominant. furthermore, right-right mixing dominates when m̃r � m̃l. − . . ps ps + % + % m~ m g~ (gev) (gev) − − ps− . . − . + % . ps ps ps − . − . . . . + % . (gev) m g~ ~m (gev) − . − − − + % + % figure : contours of sφk (thin blue), percent increase in br(b → sγ) (thick green), and ∆mbs (dashed red) for m̃r = tev, optimal mixing angle and phase, and κ = − . (left) and κ = − . (right). mass and κ with m̃r = tev and m̃r = gev. the b → sγ constraint is independent of κ, and we see how sφk decreases with the increasing mag- nitude of κ. . . dominant lr + rr mixing now we consider a second limiting case, where the diagonal left-right mixing leads to the dominant contribution to the b-quark decays. the contribution fromlr+rr mixing is enhanced in the dipole operators, so we may focus our attention on the coefficients c′g and c ′ γ. to evade the constraint from b → sγ, while simultaneously getting a large effect in sφk, we want to minimize the ratio c′γ/c ′ g, which can be done by taking larger values of x, i.e. squark masses much heavier than the gluino. in figure we reproduce figure but with a large value of µtanβ ∼ tev. in this region the lightest squark mass eigenvalue, m̃r , needs to be above tev to avoid the bound from b → sγ. for κ = − . the smallest sφk can be is about . for a small gluino mass, though this can get as low as − . for κ = − . . in this case the κ-dependence is very simple because the main contribution to sφk comes from a single operator o′g whose contribution is directly proportional to κ. thus an increased absolute value of κ directly increases the effect in sφk without affecting the bound from b → sγ. m ps ~ − − + % − . . − . . . . + % + % ps mg~ (gev) (gev) r ps ps − − − . − . . . m − − − + % + % + % . . (gev) m g~ − ps ps ps ps (gev)r ~ figure : contours of sφk (thin blue), percent increase in br(b → sγ) (thick green), and ∆mbs (dashed red) for m̃r = gev, optimal mixing angle and phase, and κ = − . (left) and κ = − . (right). − − . − − . − − . . . . κ − . − . − . ps− ps ps− m ~g (gev) + % + % + % figure : contours of sφk (thin blue), percent increase in br(b → sγ) (thick green), and ∆mbs (dashed red) for m̃r = tev, m̃r = gev, and optimal mixing angle and phase. gm ~ (gev) m~ r (gev) ps− ps − ps− + %+ % + % + % − . . . − . . . gm ~ (gev) m~ (gev) ps− ps− ps− + % + %+ % + % . . . − . − . − . figure : contours of sφk (thin blue), percent increase in br(b → sγ) (thick green), and ∆mbs (dashed red) for m̃l , m̃l , m̃r ∼ tev, optimal mixing angles and phases, µtanβ ∼ tev, and κ = − . (left) and κ = − . (right). . . combination of contributions in order to ascertain the relevance of each of these two regimes we scanned over the parameter space searching for the minimal values of sφk as a func- tion of the product µtanβ. the result is shown in figure for κ = − . and κ = − . . from the figure it is clear that for κ = − . there is a slightly larger effect on sφk for smaller values of µtanβ, though the entire region allows for a substantial deviation from the standard model. as expected, increasing the magnitude of κ increases the effect on sφk somewhat more for the larger values of µtanβ where the chromo-dipole operator gives the main contribution. to get a sense for the relative size of the rr and lr+rr contributions to sφk, we can compare the magnitude of the two terms comprising c ′ g, equation ( ). not surprisingly, for µtanβ greater than about tev the lr + rr contribution dominates by an order of magnitude. however, even for µtanβ < tev there can be points where the lr + rr contribution to the chromo-dipole operator is just as important as the rr contribution. this underscores the importance of treating this calculation in the mass eigenbasis. − . − . . . . m in (s ) tan βµ (tev) κ=− . κ=− . φ k figure : minimum values of sφk as a function of µtanβ resulting from a scan of million points that satisfied the b → sγ constraint. the upper set of points has κ = − . while the lower set has κ = − . . bs mixing mixing between b̃r and s̃r also leads to a significant contribution to bs-b̄s mixing. in our scenario the effective hamiltonian that receives such contri- butions consists of three operators that have nonzero coefficients: hsusyeff = cvrr(s̄γµprb)(s̄γµprb) + csll(s̄plb)(s̄plb) + cs×ll (s̄iplbj)(s̄jplbi). ( ) the wilson coefficients at the high scale are obtained by matching the ef- fective hamiltonian to the ∆b = squark-gluino box diagrams like those shown in figure . the result is given by : cvrr = α s m g̃ ∑ ab Γr∗saΓ r baΓ r∗ sbΓ r bb × [ − b (xa,xb) − b (xa,xb) ] ( ) csll = α s m g̃ ∑ ab Γr∗saΓ l baΓ r∗ sbΓ l bb × [ − b (xa,xb) ] ( ) cs×ll = α s m g̃ ∑ ab Γr∗saΓ l baΓ r∗ sbΓ l bb × [ b (xa,xb) ] , ( ) where the loop-functions are defined in appendix a, the Γ’s are defined in equation ( ), and again xa = m̃ a/m g̃. the leading standard model contribution to bs mixing is induced by a top quark box diagram which yields the following effective hamiltonian [ ] hsmeff = csmll (s̄γµplb)(s̄γµplb), ( ) this result differs from [ ], but agrees with subsequent analyses, e.g. [ ]. br g ~ g ~ br sr sr br ~ br ~ sr ~ sr ~ (δ )rr d (δ )rr d b b l l g ~ g ~ sr sr b b r r ~ ~ b b l l ~ ~ s s r r ~ ~ δ d ( )rr tanβµmb tanβµmb δ d ( )rr figure : diagrams contributing to bs-mixing through large b̃r-s̃r mixing. the diagram on the right induces effective b̃l-s̃r mixing which contributes to csll and c s× ll . with the wilson coefficient matched at mw csmll = g f π m w (v ∗ tsvtb) s(m t/m w ), ( ) where s(x) = x− x + x ( − x) − x lnx ( − x) . ( ) before taking the hadronic matrix element of the effective hamiltonian we must first take qcd corrections into account by using the renormalization group equations (rge) to evolve the wilson coefficients down to the low scale. the general nlo running of the wilson coefficients for a ∆b = effective hamiltonian is given in [ ] and [ ] and involves mixing among different coefficients. in our case only the two scalar left-left operators mix, while the vector right-right and the vector-left-left coefficients simply scale multiplicatively. for simplicity we have evolved both operators from mw down to the mass of the b-quark. the hadronic matrix element of the effective hamiltonian between bs and b̄s states was calculated on the lattice [ ] 〈b̄s |(s̄γµprb)(s̄γµprb)|bs〉 = mbsf bs b (µ) ( ) the supersymmetric contribution should in fact run from ∼ mg̃ down to mb. in this approximation we are ignoring corrections of order − αs(mg̃)/αs(mw ) and potential contributions from the top quark in loops which is smaller. these corrections are part of the systematic uncertainty in our calculation. 〈b̄s |(s̄plb)(s̄plb)|bs〉 = − ( mbs mb + ms ) mbsf bs b (µ) ( ) 〈b̄s |(s̄iplbj)(s̄jplbi)|bs〉 = ( mbs mb + ms ) mbsf bs b (µ), ( ) with fbs as given in table , b (mb) = . ( ) + − , b (mb) = . ( )( ), and b (mb) = . ( )( ), where the first error is statistical and the second is systematic, excluding uncertainty due to quenching. the quark masses in the above expression should be evaluated at the scale µ. the hadronic matrix element for the left-left current operator of the standard model is identical to that of the right-right operator shown in equation ( ). finally, we can write the expression for the mass difference between bs and b̄s as ∆mbs = ∣∣∣〈b̄s ∣∣∣h∆b= eff ∣∣∣bs〉 ∣∣∣ . ( ) the standard model and supersymmetric contributions interfere, h∆b= eff = hsmeff + hsusyeff . the input parameters used in the calculation are given in table . our results should be compared to the standard model prediction which can be obtained roughly by taking h∆b= eff = hsmeff in equation ( ), which yields ∆msmbs ∼ . ps− . a more rigorous treatment given in [ ] yields ∆msmbs = . + . − . ps − . ( ) however, given the substantial uncertainty in the lattice evaluation of, e.g., fbs, it is probably appropriate to inflate this error, likely to the % level [ ]. the current experimental limit, combining results from the lep experiments and sld, is [ ] ∆mbs > . ps − ( % confidence level). ( ) current and upcoming experiments are expected to be sensitive to mass dif- ferences much greater than the standard model prediction shown in equa- tion ( ). at run ii of the tevatron [ ] cdf is expected to probe up to ∆mbs of ps − while btev is expected to achieve sensitivity to values up to ∆mbs ∼ ps− . any evidence that ∆mbs > ps− from these experiments would be a clear signal of new physics. to illustrate our results we add contours of constant ∆mbs (red dashed lines) to figures - . in the case of dominant right-right contributions, i.e. parameter value parameter value parameter value mb . gev mbs . gev v ∗ tsvtb − . mt gev fbs mev αs(mz) . mw . gev mz . gev τbs . ps table : input parameters used in the calculation of sφk and ∆mbs. small µtanβ, the trend is similar to that of the previous section; lighter gluino and squarks give a larger susy contribution and thus increase ∆mbs . note that the supersymmetric contribution to the mass difference dominates over the standard model in significant regions of the supersymmetric parameter space, easily allowing ∆mbs > ps − where right-right mixing dominates. such values for ∆mbs are certainly beyond the reach of the experiments mentioned above. in the case of dominant lr + rr mixing the modification of bs mixing is not as striking. in the example given in figure values of ∆mbs are much closer to the standard model prediction. restricting ourselves to areas that respect the b → sγ bound gives a yet lower value, within the reach of upcom- ing experiments. we should point out that this is not generic since figure only represents a slice of parameter space. other choices of parameters can give higher values of ∆mbs (above ps − ) for high values of µtanβ. the correlation of these results to those in b d → φks will be discussed in the next section. finally, we should comment about possible cp violation in the bs-b̄s system. in the standard ckm scenario the bs → b̄s amplitude does not have a cp violating phase (in the wolfenstein parameterization), so no indirect cp violation is expected. in our scenario, however, bs mixing can involve the phases from the down-squark mass matrix. in the cases where the susy contribution to bs mixing dominates the sm, measurements of cp violation in bs → j/ψφ will be sensitive to these phases. correlation in this section we will discuss the correlation between sφk and ∆mbs in the context of large b̃-s̃ mixing. because the effect on bs mixing is very different for the two limiting regions of parameter space, we will discuss them separately. . dominant rr mixing in this region of parameter space the operators o′ − make large contributions to sφk, while there is essentially only one contribution to bs mixing, namely that from the operator shown in equation ( ). unfortunately there is no simple, precise, relationship between the combination of the ∆b = oper- ators and the operator responsible for bs mixing. in general, they depend quite differently on loop functions. in spite of this, one can make the following strong statement. in cases where there is a large shift in sφk away from the standard model expectation due to the operators o′ − , and the rr contribution to o′g (the dominant right-right mixing scenario), there is a large contribution to bs mixing. to see this, we first note that the squarks and gluino must not be too heavy, and the b̃-s̃ mixing must be large in order to have a large contribution to sφk. this suggests a minimum contribution to the bs mixing. however, there is the worry that it might be possible to fine-tune parameters to somehow drastically suppress the contribution to bs mixing; for example, by choosing squark and gluino mass ratios to minimize the value of the functions b and b in equation ( ). we find that this is not possible, however. in order to have a very large contribution to sφk, one is pushed into a region of pa- rameter space where the gluino, and at least one of the down-type squarks is light. furthermore, the splitting between this light squark, which represents a mixture of b̃ and s̃ squarks, and the masses of the heavier squarks must be large to avoid a super-gim cancellation. once this qualitative picture for the spectrum is identified, it is easy to check that there cannot be a cancellation of the contribution to bs mixing in this case. now we present our results quantitatively. since our goal here will be to show that large deviations in sφk will correspond to large contributions to bs mixing, we plot the minimum achievable value of ∆mbs for a given value of sφk. the minimum is found by scanning a parameter space that consists of the parameters {mg̃,m̃l ,m̃r ,m̃r ,cosθ ,φ }. as discussed in equation ( ), cosθ represents the mixing angle between the right-handed b̃ and s̃ squarks, and φ represents the phase corresponding to this off-diagonal term. as a parameter space, we take: mg̃ ∈ ( , ) gev ( ) m̃l ∈ ( , ) gev m̃r ∈ ( , ) gev m̃r ∈ ( , ) gev θ ∈ ( ,π/ ) φ ∈ ( , π). the lower limits on the masses are motivated by direct searches, while the upper limits are motivated by naturalness considerations. a scan would generate a scatter plot of sφk vs. ∆mbs. for a given resultant value of sφk, we find the combination of parameters that yields the smallest contribution to bs mixing. this is essentially equivalent to taking the boundary of the region generated by the scatter plot. as discussed in section , there is considerable dependence on the variable κ, which has a relatively large uncertainty. so we repeat the above exercise for several values of κ, displaying the results in figure . adding the constraint from b → sγ modifies these results as shown in figure . the contours in figure notably do not extend as low in sφk because the b → sγ constraint removes the region of parameter space that allowed us to obtain those values in figure . the take-home message from the figures is a simple one. if the hint of the deviation in sφk measured in the b → φks persists and it is attributable to a scenario with dominant rr squark mixing, it will result in a large contribution to bs mixing, which will be a clear indication of new physics observable at the tevatron. . dominant lr + rr mixing in the region of parameter space where µtanβ is relatively large, the expec- tation for ∆mbs is very different. in this region the main contribution to sφk comes from the lr + rr contribution to the dipole operator o′g. this contribution can be sizeable even when the squarks and gluinos are heavy (squarks can be at the tev level or higher). this is the significant difference between the two limiting cases. heavy squarks and gluino mean that the contributions from the operators o′ − are small. similarly, the operators re- sponsible for bs mixing, which come from box diagrams and resemble o′ − , can also be small. the bottom line is that a large contribution to sφk is possible without a large addition to ∆mbs. this is borne out numerically, − . . − ∆ ∆ b b φ φ s ss s κ= − . κ= − . κ= − . m m − vs. γno b s k k (ps ) figure : the minimum value of ∆mbs for a given value of sφk. it is found by scanning over the parameter space given in equation ( ). the corresponding curve is shown for several values of κ, the coefficient of the dipole operator, as defined in equation ( ). . . . . − . ∆ ∆ b b φ φ s s s s κ= − . κ= − . κ= − . m m − vs. k (ps ) figure : the same as figure , but with the b → sγ constraint applied as discussed in the text. the minimum value of ∆mbs for a given value of sφk. it is found by scanning over the parameter space given in equation ( ). the corresponding curve is shown for several values of κ, the coefficient of the dipole operator, as defined in equation ( ). ∆mb s (ps )− tanµ β (tev) ∆mb s (ps )− tanµ β (tev) figure : maximum and minimum values of ∆mbs as a function of µtanβ resulting from a scan of points in the parameter space with sφk < . and κ = − . . the plot on the left shows an enlargement of the region of small µtanβ. as shown in figure , where the points allowed by the b → sγ constraint all give ∆mbs very close to the standard model expectation. we have seen that the lr + rr contribution to sφk can be important even for fairly small values of µtanβ, so it is natural to wonder what con- clusions can be drawn about ∆mbs in the regions where both contributions are important. to answer this question we again performed a scan of the pa- rameter space, this time collecting points with maximal and minimal ∆mbs as a function of µtanβ with the additional requirement that sφk < . for the nominal value κ = − . . the results are shown in figure . in ac- cord with what was stated above, points with the largest µtanβ give smaller contributions to bs mixing. in fact, for µtanβ > tev any effects on ∆mbs will be indistinguishable from the standard model expectation. this apparent upper bound may be interpreted as follows. for large µtanβ the severe b → sγ bound is pushing us to regions where rr mixing is small or masses are high, both of which disfavor large contributions to bs mixing. at the other end of the spectrum, for µtanβ < tev all points in the scan gave values of ∆mbs > ps − , a clear signal of new physics above even the largest standard model predictions. this trend continuously connects us back to the result of the previous subsection. mixing between the first two generations of squarks has fallen outside the main scope of this paper. we should mention, however, that larger values of the lightest squark masses, around gev, may well be preferred by the results are nearly identical when κ = − . and sφk < − . . constraints from k-k̄ mixing. to see this, note that if we believe that the cabibbo angle originates through the down yukawa matrices, then the down yukawa matrix has the structure: λd = ( hd hsλc h hs ) , ( ) where h is some unknown yukawa coupling and λc is the sine of the cabibbo angle. diagonalizing this matrix requires a rotation on dl and sl of o(λc) which induces an off-diagonal element of order hdλc. using the phenomeno- logical relationship, md/ms ≈ λ c, we find that a rotation between dr and sr of o(λ c) is needed to complete the diagonalization. then, due to the lack of degeneracy between the squarks, the induced d̃-s̃ mixing can lead to a large contribution to the k-k̄ mixing. this suggests that heavier squark masses, perhaps above gev are preferred, barring some accidental cancellation with the (unknown) ( , ) element, h, in the above matrix. by the above reasoning, if one wishes to achieve an sφk that differs significantly from the value of sin β as measured in the in the b d → j/ψks channel, there may a theoretical prejudice to prefer the scenario where the lr+rr contributions dominate sφk, since in that case large squark masses are more easily accommodated while still giving a large effect due to the mg̃/mb enhancement. conclusion there exist a class of models, motivated by grand unified theories and the large observed mixing in atmospheric neutrinos, where it is natural to have a large mixing between the right-handed b̃ squark and s̃ squark. we have found that there exists a range of parameters where such mixing induces a significant deviation in sφk from the standard model expectation of sin β as measured in the channel b d → j/ψks. in particular, the central value for sφk from babar and belle can be accommodated without conflicting with the measured value of b → sγ, but there is some tension. the value of κ, the hadronic matrix element for the chromo-dipole operator, must be larger than the naive estimates for its value. there are two possible origins of a substantial modification to sφk. the first solely involves a large right-right mixing, with no contribution from the mixing proportional to mbµtanβ. in this case a small gluino mass is required, near the experimental bound. correspondingly, there is a large contribution to bs mixing, a consequence which will be testable at the tevatron run ii. in the second case, we consider the mixing from the combination of the large right-right mixing and a large mbµtanβ. in this case, squarks and gluinos need not be light, so bs mixing need not be large. in particular, for very large values of µtanβ the prediction for bs mixing is indistinguishable from the standard model prediction, when current errors on lattice matrix elements are taken into account. however, a substantial improvement in the standard model prediction for bs mixing still may allow an effect to be seen at the tevatron in this case. note added while completing this paper we received references [ , ]. there is some overlap with these papers, which also consider supersymmetric contributions to b d → φks. regarding [ ], in places that we overlap, we agree qualitatively with their results, though there may be some quantitative differences. these are likely due to the fact that they work in the mass insertion approximation. indeed, allowing large mixings and hierarchies that cannot be described by mass insertions gives us larger contributions in the ‘pure’ rr mixing case. other possible differences may arise from a different treatment of the hadronic matrix elements and the fact that constraints from b → sγ were not imposed in the same way. we appear to disagree with [ ], which seems to find a strong suppression of the contribution from the δrr mass insertion. we differ from both papers in our emphasis on the mixing induced by a combination of mbµtanβ along with a large flavor-changing rr element in the squark mass matrix. in those treatments, each mass insertion is consid- ered separately, including flavor off-diagonal lr mixing. we should point point out that the lr+rr mixing does not necessarily describe the same physics as a single lr flavor mixing insertion. treating a lr + rr mixing as a pure δrl may miss important contributions due to the rr mixing only. for example, we find maximal values of ∆mbs for intermediate values of µtanβ which are much higher than those achieved in [ ] with lr mixing. this might be due to a rr mixing contribution which is sub-dominant in sφk but which nevertheless gives a large contribution to ∆mbs. this example illustrates how our framework differs from analyses which consider only one mass insertion at a time. acknowledgments we would like to thank zoltan ligeti, gustavo burdman, and yuval gross- man for useful conversations. ap would also like to thank gudrun hiller for additional conversations. this work was supported in part by the director, office of science, office of high energy and nuclear physics, division of high energy physics of the u.s. department of energy under contracts de-ac - sf and de-ac - sf and in part by the national science foundation under grant phy- . a loop functions we include the loop functions for completeness. we use the same definitions as in [ ]. here xa ≡ m d̃a/m g̃. b (xa,xb) = ∫ ∞ − z dz (z + ) (z + xa)(z + xb) ( ) = − x a logxa (xa −xb)(xa − ) − x b logxb (xb − xa)(xb − ) − (xa − )(xb − ) , ( ) b (xa,xb) = ∫ ∞ zdz (z + ) (z + xa)(z + xb) ( ) = − xa logxa (xa −xb)(xa − ) − xb logxb (xb −xa)(xb − ) − (xa − )(xb − ) , ( ) c (x) = x − x + x− − logx ( − x) , ( ) c (x) = − x + x − x + + x ( x− ) logx ( − x) . ( ) d (x) = −x + x − x − − x logx ( −x) , ( ) d (x) = −x + + x logx (x − ) , ( ) d (x) = x + x − x + − x logx ( − x) , ( ) d (x) = − x + x− + x logx (x − ) , ( ) ( ) b chromo-dipole matrix element for b d → φks in this appendix we show explicitly the computation of the matrix element of o(′)g in the naive factorization approximation. the computation of a similar quantity for b̄ → π+π− decay can be found in [ ]. we start with og = gs π mb(s̄iσ µνtaijprbj)g a µν ( ) and then connect a quark current through a virtual gluon to form a four- quark operator. this step depends on the convention used for the covariant derivative. our convention is that dµ = ∂µ +igt aaaµ, and we have checked that this is consistent with the wilson coefficients for both the standard model and susy contributions. this yields the operator og = i αs π kν k mb(s̄iσ µνtaijbj)(q̄kγµt a k�q�) ( ) where k = pb − ps is the gluon momentum. in the naive factorization ap- proximation the color-octet current, (q̄kγµt a k�q�), cannot produce a physical φ, so the φ must be produced by the s̄ and q operators. to factor the matrix element we first use the equations of motion to simplify the tensor current. this yields: og = − αs πk mb { mb(s̄γ µplt a ijb) + ms(s̄γ µprt a ijb) − pµb (s̄iprtaijbj) } × (q̄kγµt a k�q�) ( ) in particular, note that [ ] appears to use the opposite convention of [ , ]. where the last term was simplified using the conservation of the quark cur- rent, kµ(q̄kγµt a k�q�) = as in [ ]. then by a fierz transformation and judi- cious use of dirac matrix identities, this can be brought to the form [ , , ] og = − αs πk mb n c − n c ( δi�δkj − nc n c − tai�t a kj ) ( ) × [ mb(s̄iγµplq�)(q̄kγµplbj) − mb(s̄iprq�)(q̄kplbj) + ms(s̄iγ µprq�)(q̄kγµprbj) − ms(s̄iplq�)(q̄kprbj) + (pb)µ {(s̄iγµplq�)(q̄kprbj) + (s̄iprq�)(q̄kγµprbj) +i(s̄iσ µνprq�)(q̄kγ νprbj) − i(s̄iγνplq�)(q̄kσµνprbj)}] next we use the following parameterization for matrix elements. 〈φ(pφ, ,φ)|s̄γµs| 〉 = fφm φ,µφ ( ) 〈φ(pφ, ,φ)|s̄s| 〉 = ( ) 〈φ(pφ, ,φ)|s̄σµνs| 〉 = −ifφm φ ms m φ (, µ φp ν φ − ,νφpµφ). ( ) also, 〈k̄ (pk)|s̄γµb|b̄ d(pb)〉 = (pb + pk)µf+(t) + (pb −pk)µf−(t) ( ) 〈k̄ (pk)|s̄b|b̄ d(pb)〉 = δ− bs ∆bkf+(t) + δ− bs (pb −pk) f−(t) ( ) 〈k̄ (pk)|s̄σµν( ±γ )b|b̄ d(pb)〉 = − is(pµbpνk − pνbpµk) ± sεµνλσ(pbλpkσ −pbσpkλ). ( ) here t = (pb − pk) , ∆bk ≡ m b − m k, and δbs ≡ mb − ms. notice we have corrected the sign in equation ( ) compared to the similar expression in [ ]. heavy quark effective theory gives the relation s = (f+ −f−)/ mb [ ]. we also make the kinematic assumptions that the b-quark carries all of the b- meson momentum and that the φ momentum is equally divided between its two constituent s-quarks. thus pb = pb and k = (m b − m φ/ + m k). putting all the pieces together gives: κ = −m b k   + m b − m k + m φ f−f+ mb(mb − ms)   + −m b k [ m k − m b − m φ m b ( − f− f+ ) + ms mb ( f− f+ )] ( ) because the matrix element is nonsingular we have f−( ) = . then for small t, due to simple pole dominance we have f−(m φ) � f−( ) = . [ ] by ignoring the difference between b-quark and b-meson masses we arrive at the estimate cited earlier, κ = − + o ( m φ m b ) � − . . the sign convention differs from [ ], and the slight difference in magnitude can be traced to our replacement of (pb +ps) µ with p µ b using the conservation of the added quark current. in [ ] a similar quantity s̃φk = κ is used. however, they quote a value s̃φk � − . which appears to match s̃ππ found in [ ]. this would correspond to a value of κ � − . . references [ ] y. fukuda et al. [super-kamiokande collaboration], phys. rev. lett. , ( ) [arxiv:hep-ex/ ]. [ ] q. r. ahmad et al. [sno collaboration], phys. rev. lett. , ( ) [arxiv:nucl-ex/ ]. [ ] [kamland collaboration], arxiv:hep-ex/ . [ ] a. alavi-harati et al. [ktev collaboration], phys. rev. lett. , ( ) [arxiv:hep-ex/ ]; v. fanti et al. [na collaboration], phys. lett. b , ( ) [arxiv:hep-ex/ ]. [ ] b. aubert et al. [babar collaboration], phys. rev. lett. , ( ) [arxiv:hep-ex/ ]; k. abe et al. 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[ ] w. n. cottingham, i. b. whittingham, n. de groot, and f. wilson, arxiv:hep-ph/ . http://lepbosc.web.cern.ch/lepbosc/combined_results/amsterdam_ / introduction cp violation in b s transition effective hamiltonian bd ks constraints from bs numerical analysis dominant right-right mixing dominant lr+rr mixing combination of contributions bs mixing correlation dominant rr mixing dominant lr+rr mixing conclusion loop functions chromo-dipole matrix element for bd ks error federal reserve bank of philadelphia skip to main content skip to footer search expand menu about us our people education banking careers calendar of events the economy expand sub-topics monetary policy banking & financial markets macroeconomics regional economics consumer finance expand sub-topics payment systems consumer credit education finance mortgage markets community development expand sub-topics inclusive growth credit & capital housing & neighborhoods workforce & economic development surveys & data expand sub-topics real-time data research regional economic analysis community development data search we're sorry! we can't find the page you're looking for. try navigating back to the homepage, or use the search. contact us ten independence mall philadelphia, pa ( ) - facebook twitter youtube linkedin privacy notice newsroom subscribe copyright . all rights reserved. federal reserve bank of philadelphia home search this site associate professorusc school of philosophy trousdale parkwaylos angeles, ca - office: stonier hallemail: jacobmro [at] usc [dot] edu usc department website curriculum vitae i am an associate professor of philosophy at the university of southern california. i received my ba in philosophy from the university of toronto and my phd in philosophy from rutgers university. my research is mainly in ethics, epistemology, and practical reason. published and forthcoming from teleosemantics to normative ethicsthis paper attempts to answer the question "what kinds of action are morally wrong?" by first asking the question "what kinds of action is it fitting for us to morally disapprove of?" and it argues that a teleosemantic framework can allow us to answer the second question and hence the first. knowledge dethroned(with andreas mueller) forthcoming, analytic philosophythis paper criticises the knowledge first view of practical reasoning, according to which one should reason only on the basis of what one knows. one well-known objection to this view is the problem of partial belief: it seems that partial beliefs or credences that do not constitute knowledge can figure in good practical reasoning. while a number of ingenious solutions to this problem have been proposed, we argue that none can succeed and hence that the problem of partial belief is insurmountable. knowledge, safety, and meta-epistemic beliefforthcoming, pacific philosophical quarterlythis paper raises problems both for the view that safe belief is necessary for knowledge and for the view that it is sufficient. focusing on “meta-epistemic beliefs,” or beliefs about the epistemic status of one’s own beliefs, it is shown that the necessity claim has counterintuitive implications and that the sufficiency claim implies a contradiction. it is then shown that meta-epistemic beliefs raise similar problems for a wide range of accounts of knowledge, and hence that they provide a powerful test for theories of knowledge. idealism and fine tuningforthcoming, idealism: new essays in metaphysics, edited by t. goldsmith and k. pearcethis paper argues that, given certain background assumptions, a kind of idealism follows from a version of the fine-tuning thesis. in particular, it argues that a strong version of the fine-tuning thesis, together with a unificationist account of explanation, imply what i call explanatory idealism, which is the view that the mental has explanatory priority (though not ontological ontological priority) over the physical. moral skepticism(with matt lutz) , routledge handbook of metaethics, edited by t. mcpherson and d. plunkettwe argue that central to many of the arguments for moral skepticism is the idea that our moral beliefs do not have the right kind of explanatory connection to the moral truths they purport to represent. we then formulate what we take to be the strongest argument of this kind, which we call the explanatory trilemma argument. we conclude by critically examining a variety of responses to this kind of argument. on losing disagreements: spencer's attitudinal relativism (with mark schroeder) , mindhere we respond to jack spencer, who claims to have resolved the dilemma we posed in "reversibility or disagreements." his attempted solution turns on a view about belief that he calls "attitudinal relativism." we argue that this view fails to solve our dilemma. in particular, the relativist who adopt this view will sacrifice the claims about disagreement that motivate her position. rethinking the person-affecting principle , journal of moral philosophythis paper concerns person-affecting principles (on which a first outcome can be better than a second only if it is better for someone) and their implications for the transitivity of the better-than relation. i argue that standard formulations of such principles face serious problems, and i propose an alternative formulation in their place. i conclude by arguing that plausible versions of the principle can be reconciled with the transitivity of identity. divided we fall: fission and the failure of self interest , philosophical perspectivescases involving personal fission raise a challenge for the self-interest thesis, i.e., the view that we have special reason to be concerned about our own welfare. several philosophers have attempted to offer metaphysical solutions to this challenge: they have argued that, if we adopt the right view about what happens in fission cases, we can hold on to the self-interest thesis while avoiding counter-intuitive implications. i argue that no such solution can succeed. the principle of sufficient reason and the grand inexplicable , the puzzle of existence: why is there something rather than nothing, edited by tyron goldschmidt.it has been argued that the principle of sufficient reason must be false. for, assuming there are any contingent propositions at all, it has been argued that there must be some contingent proposition (call it the "grand inexplicable"), for which there is no explanation. i defend the principle of sufficient reason against arguments of this kind. belief, credence and pragmatic encroachment (with mark schroeder) , philosophy and phenomenological research (with mark schroeder)we compare two alternative theories of outright belief and its relation to credence. we criticize one view, which we call pragmatic credal reductivism, according to which believing a proposition consists in having sufficient credence in it for practical purposes. and we propose and defend an alternative view, which we call the reasoning disposition account, according to which believing a proposition consists in having a defeasible disposition to treat it as true in reasoning. reversibility or disagreement (with mark schroeder) , mindthis paper concerns the debate between contextualists and relativists over a family of expressions that includes both epistemic and deontic modals (“might,” “must,” “ought,” etc.). we argue that these expressions all display an important but largely overlooked feature that we call reversibility: they give rise to sentences that one can rationally and sincerely assertively utter while knowing that one will later rationally and sincerely assertively utter their negations. we argue that this phenomenon undermines claims about disagreement that have been used to support relativism. repeatable artwork sentences and generics (with shieva kleinschmidt) , art and abstract objects, edited by christy mag uidhirthis paper concerns repeatable artwork sentences, such as "the moonlight sonata has three movements," as well as generic sentences, such as "the polar bear has four paws." we argue that these kinds of sentences should be given a uniform treatment, and that neither one has the subject predicate form it appears to have. consequently, the truth of these sentences does not entail that there is anything referred to by "the polar bear" or "the moonlight sonata." rationality, normativity, and commitment , oxford studies in metaethics, volume , edited by russ shafer-landau.i consider three challenges to the normativity of rationality: the ignorance problem (which concerns cases where we are rationally required to do what we have most objective reason not to do), the wrong kind of reasons problem (which concerns cases where we seem to have overwhelming pragmatic reason to have irrational attitudes), and the mere incoherence problem(which concerns cases where a combination of attitudes is rationally prohibited, and yet we have sufficient reason for each of the constituent attitudes). after criticizing traditional responses to each of these challenges, i offer an account of the connection between rationality and reasons that answers all of them and that has considerable explanatory power. actualism, possibilism and beyond , oxford studies in normative ethics, volume , edited by russ shafer-landau.how should we act when we don't currently have perfect deliberative control over our future conduct? actualists say that we should f when f-ing would be preferable to what we would do otherwise, whereas possibilists say that we should ? when all our maximally preferable options involve f-ing. i argue that neither of these views can succeed, and i propose an alternative view that avoids the difficulties facing each. all roads lead to violations of countable additivity , philosophical studies. this paper criticizes an attempt by brian weatherson to provide a countable additivity-friendly argument for the one-third solution to the sleeping beauty problem. sleeping beauty, countable additivity, and rational dilemmas , philosophical review. (selected for the philosopher's annual) i argue that the main arguments for the / solution to the sleeping beauty problem entail a more general principle (what i call the generalized thirder principle) which conflicts with the principle of countable additivity. i argue that the most plausible response to this conflict is to accept both principles and to maintain that, in cases where they conflict, rational dilemmas arise. the irreducibility of personal obligation , journal of philosophical logic.i argue that claims about personal obligation (of the form “s ought to f”) cannot be reduced to claims about impersonal obligation (of the form “it ought to be the case that p”). any such reduction, i argue, will have unacceptable implications in coordination problems involving multiple agents. supplement: conditional analyses of personal obligation how to be a cognitivist about practical reason , oxford studies in metaethics, volume , edited by russ shafer-landau.cognitivism about practical reason is the view that intentions involve beliefs and that rational norms on intentions can be explained in terms of rational norms on the beliefs they involve. this paper provides a detailed examination of the prospects of cognitivism and of the challenges it faces. in it i argue that the self-referential account of intentions typically adopted by cognitivists will not serve their purposes, and i propose an alternative account which, i argue, is more promising. should kantians be consequentialists? , ratio.parfit argues that rule consequentialism can be derived from the most plausible formulation of kantian ethics, and hence that kantians should be consequentialists. i argue that there is strong reason to reject two of the assumptions that figure in this derivation. derek parfit , modern philosophers, edited by christopher belshaw and gary kemp, wiley-blackwell. review of john broome's weighing lives , the philosophical review. rejecting ethical deflationism , ethics.i consider what i call deflationary ethical theories, including nihilism and relativism. drawing a distinction between practical acceptance and rejection, on the one hand, and belief and disbelief, on the other, i argue that we have strong reason to reject these theories from the practical point of view even if we don't have reason to disbelieve them. in preparation comments welcome. please don't quote without permission. from moral wrongess to moral blame i sketch a sentimentalist account of moral wrongness. on this account, moral blame is conceptually prior to moral wrongness, and morally wrong actions are to be understood as the kind of actions which, if done responsibly or without an excuse, would be worthy of moral blame. an essential component of this approach, which i defend in the paper, is a noncognitivist view of moral blame that does not define this attitude in terms of judgments of moral wrongness time travel, subjunctive conditionals, and the limits of rational choiceandy egan has argued that causal decision theory has unacceptable implications time-travel cases where one's circumstances of action are affected by one's choice. i argue that this objection to causal decision theory is based on highly questionable assumptions. the real challenge posed by these past- affecting choice situations is not that causal decision theory misevaluates our options, but rather that it cannot evaluate our options at all. saving the appearances: distinguishing evidence from knowledgei argue against williamson's identification of knowledge with evidence consequentialism and actual rulesi defend a version of rule consequentialism according to which the rules we have reason to follow are not those whose general acceptance would have good consequences, but rather those whose general acceptance in fact has good consequences. i then consider the problem of how this moral theory could be derived from more fundamental principles. ace other work acceptance and practical reason (my dissertation) the bear named 'e' report abuse page details page updated google sites report abuse philosophies article sleeping beauty on monty hall michel janssen ,* and sergio pernice school of physics and astronomy, university of minnesota, church street s.e., minneapolis, mn , usa business school, university of cema, av. córdoba , buenos aires c aap, argentina; sp@cema.edu.ar * correspondence: janss @umn.edu received: july ; accepted: august ; published: august �� abstract: inspired by the monty hall problem and a popular simple solution to it, we present a number of game-show puzzles that are analogous to the notorious sleeping beauty problem (and variations on it), but much easier to solve. we replace the awakenings of sleeping beauty by contestants on a game show, like monty hall’s, and increase the number of awakenings/contestants in the same way that the number of doors in the monty hall problem is increased to make it easier to see what the solution to the problem is. we show that these game-show proxies for the sleeping beauty problem and variations on it can be solved through simple applications of bayes’s theorem. this means that we will phrase our analysis in terms of credences or degrees of belief. we will also rephrase our analysis, however, in terms of relative frequencies. overall, our paper is intended to showcase, in a simple yet non-trivial example, the efficacy of a tried-and-true strategy for addressing problems in philosophy of science, i.e., develop a simple model for the problem and vary its parameters. given that the sleeping beauty problem, much more so than the monty hall problem, challenges the intuitions about probabilities of many when they first encounter it, the application of this strategy to this conundrum, we believe, is pedagogically useful. keywords: sleeping beauty problem; monty hall problem; probability; bayesian; frequentist . warm-up exercise: the three stooges on monty hall consider the following puzzle. in a special edition of his famous game show, “let’s make a deal”, monty hall calls the three stooges to the stage and has them collectively pick one of three doors, d , d or d . behind one are two checks for a thousand dollars each, behind the other two is a goat. the three stooges pick d . before the show goes to a commercial break, monty tells his special guests that either one or two of them will be called back after the break. if they were wrong, only one of them will return (but he does not tell them which one); if they were right, the other two will. during the break, the three stooges are made to take a nap backstage. when the show resumes, they are sound asleep. if the checks are not behind d , monty wakes up curly and brings him back to the stage, making sure he has no idea whether he is the first or the second one to be woken up and brought back. as usual, monty opens either d or d (whichever one has a goat behind it) and offers curly to switch from d to the other door that remains unopened. if the door he chooses has the two checks behind it, he gets one of them. if not, he goes home empty-handed. if the checks are behind d , monty goes through this same routine twice, with moe and larry (not necessarily in that order), the only other difference being that he now has a choice whether to open d or d . monty makes sure that neither of them finds out whether they were woken up and brought back first or second (at least not until monty opens the door with the checks behind it, one of which may be gone at that point). philosophies , , ; doi: . /philosophies www.mdpi.com/journal/philosophies http://www.mdpi.com/journal/philosophies http://www.mdpi.com http://dx.doi.org/ . /philosophies http://www.mdpi.com/journal/philosophies https://www.mdpi.com/ - / / / ?type=check_update&version= philosophies , , of what is a stooge to do in this predicament? should he switch? should he stay with the door they initially picked? should he be indifferent between staying and switching? . introduction: monty hall and sleeping beauty the puzzle in section combines elements of two well-known puzzles challenging our intuitions about probability: the monty hall problem and the sleeping beauty problem. the solution of the monty hall problem is no longer controversial. a contestant in a normal episode of “let’s make a deal” should always take monty hall up on his offer to switch. because monty hall never opens the door with the prize behind it and, thus, has to know which door that is, we need to assume that he offers contestants to switch regardless of which door they initially picked, but that assumption is routinely granted. given this assumption, the intuition that the opening of a door and the offer to switch are just for dramatic effect and do not affect the contestant’s chances of winning is simply wrong. the opening of one of the doors provides the contestant with important information. a simple and (judging by its ubiquity on the web) effective way to make the point is the following (though the key assumption mentioned above is not always spelled out). initially, the contestant only has a / chance of picking the right door and a / chance of picking the wrong one. suppose he (or she) switches. if he was right the first time, he will now be wrong. if he was wrong the first time, he will now be right. accordingly, he now has a / chance of being right and only a / chance of being wrong. in a slogan, he flips the odds by switching. a device often used to shore up one’s intuitions in this case is to increase the number of doors. if there are n doors (n ≥ ), the contestant initially has a /n chance of picking the right one and a (n − )/n chance of picking the wrong one. after the contestant has made her (or his) initial choice, monty hall opens all but one of the remaining doors and offers her to switch. once again, the contestant flips the initial odds by switching. by switching, she effectively guesses that the prize is not behind the door she initially picked but behind any one of the other n − doors, all but one of which monty hall has meanwhile opened for her. unlike the monty hall problem, the sleeping beauty problem remains controversial. the problem is essentially the following. sleeping beauty is told that a fair coin will be tossed after she has been put to sleep and that, when she is woken up, she will be asked what her degree of belief is that the coin came up heads. it depends on the outcome of that coin toss, however, how many times she is asked. if the coin comes up heads, she will only be woken up and asked once. if the coin comes up tails, she will be woken up and asked twice. the first time she’s woken up after the coin comes up tails she is given some amnesia drug so that she won’t remember the second time that she’s been woken up before and asked the same question. every precaution is taken to make sure that sleeping beauty, when she wakes up, cannot tell whether her current awakening is the one after the coin came up heads or one of the two after the coin came up tails. what should sleeping beauty’s degree of belief be upon being awakened that the coin came up heads? one knee-jerk response is that, no matter how often sleeping beauty is put to sleep, woken up, and drugged, the probability that a fair coin comes up heads is and remains / . therefore, her answer every time she is asked should be / . another knee-jerk response is that, since she will be asked twice if the coin comes up tails, and only once if the coin comes up heads, she is twice as likely to be asked when the coin comes up tails. therefore, her answer every time she is asked should be / . those who think the answer is / are known as halfers. those who think the answer is / are known as the impatient reader can turn to section right away for the solution to this puzzle. three honors students at the university of minnesota (rose adams, jamie debruyckere, and terrance gray) worked with one of us (mj) to make a video posing this riddle. we used drawings by laurent taudin as the basis for the animation. scott spicer and charlie heinz of library media services at the university of minnesota helped the students to record the voice-overs and the soundtrack. the result was posted on youtube: see https://www.youtube.com/watch?v= u - cwb vq. there is a vast literature on both. good places to start are the wikipedia entries for these two problems. https://www.youtube.com/watch?v= u - cwb vq. philosophies , , of thirders. the debate between halfers and thirders has long moved beyond this clash of intuitions upon first encountering the problem. we strongly suspect that it persists mainly because it is ambiguous exactly what sleeping beauty is being asked. in order get a better handle on the sleeping beauty problem and inspired by the monty hall problem, we design a game-show proxy for it, in which (potential) contestants take over the role of (potential) awakenings. our analysis will show that both halfers and thirders are right, depending on how one interprets the question sleeping beauty is asked. that said, our game-show proxy will be much more congenial to thirders than to halfers as it implements the interpretation of the question they would consider to be the interesting one. should the information that sleeping beauty is given ahead of time about what will happen depending on the outcome of one toss of a fair coin change her degree of belief upon being awakened that this particular coin toss resulted in heads? upon a little reflection, both halfers and thirders will agree that if that is the question, sleeping beauty would be just as mistaken to ignore this information as contestants on “let’s make a deal” would be to ignore the information monty hall is giving them by opening one of the three doors. just as sleeping beauty knows how a coin toss will decide how many of her potential awakenings will become actual awakenings, potential contestants in our game-show proxy know how a coin toss will decide how many of them will become actual contestants. sleeping beauty and our potential contestants are both asked to assess (one way or another) the probability that this coin toss resulted in heads when woken up or selected as a contestant, respectively. using bayes’s rule, they should update their degree of belief that the coin came up heads in light of the information about how potential awakenings/contestants become actual awakenings/contestants. in the spirit of a time-honored bayesian tradition (based on the principle that you put your money where your mouth is), we will cash out the degrees of belief of our game-show contestants in terms of betting behavior. if our contestants update according to bayes’s rule (and the same is true for sleeping beauty), their prior degrees of belief, determined by the symmetry of the coin, get replaced by posterior degrees of belief that are determined by the numbers of contestants (awakenings) selected for the two possible outcomes of the coin toss— for heads, for tails in the original problem but those numbers can be chosen arbitrarily. although the paper is mostly written in terms of credences or degrees of belief, the analysis does not require this interpretation of probabilities. it can easily be rephrased in terms of relative frequencies in long series of repetitions of our game show. similar game-show proxies can be designed for variations on the sleeping beauty problem, in which the coin toss is replaced by a different stochastic experiment with an arbitrary number of outcomes and arbitrary numbers of candidates (awakenings) for different outcomes. as in the case of the monty hall problem, a good way to shore up one’s intuitions in dealing with the sleeping beauty problem, as we will see in sections and , is to vary these parameters. in section , we illustrate this strategy for getting a handle on the sleeping beauty problem by designing a game-show proxy for a variation on the problem that combines it with the monty hall problem (for arbitrary numbers of doors the sleeping beauty problem is due to elga [ ], who took the thirder position. his paper provoked a response by lewis [ ], who took the halfer position. for an up-to-date review of the professional literature on the sleeping beauty problem, see cisewski et al. [ ]. as albert einstein wrote to the italian mathematician tullio levi-civita on august , : “it must be a pleasure to ride through these fields on the steed of real mathematics, while the likes of us have to muddle through on foot” (es muss hübsch sein, auf dem gaul der eigentlichen mathematik durch diese gefilde zu reiten, während unsereiner sich zu fuss durchhelfen muss) ([ ], doc. ). cisewski et al. throw everything and the kitchen sink at sleeping beauty. the only mathematical tool we will use is bayes’s theorem. for the use of bayesian reasoning in connection with both the sleeping beauty problem and the monty hall problem, see the dissertation by bradley [ ]. bayes’s theorem is named after the reverend thomas bayes (c. – ). it was published posthumously by his friend richard price in . the modern mathematical formulation as well as the modern use of the theorem go back to pierre-simon laplace (see mcgrayne [ ], p. ). there is a simple and a general version of the rule (see note for a simple derivation). in , independently of bayes, laplace found the simple rule (mcgrayne [ ], p. , p. ); in , he found the general rule ([ ], p. ). for the purposes of the sleeping beauty problem, the simple rule suffices (sections and ) but for the variations on the problem that we will consider in sections and we need the general rule. in true bayesian fashion, hitchcock [ ] offers a diachronic dutch book argument in support of the thirder position. philosophies , , of and awakenings). the scenario with the three stooges in section is essentially our game-show proxy for this combined problem for three doors and three awakenings. in section , we use the game-show proxy for the combined problem to tweak the so-called – lifeline in the tv show “who wants to be a millionaire?” in this game show, unlike the preceding ones, the degrees of belief used as priors in our bayesian analysis no longer reflect symmetries of physical systems. however, the analysis can still easily be rephrased in frequentist terms. . game-show proxies for (variations on) the sleeping beauty problem we introduce a new game show loosely modeled on monty hall’s “let’s make a deal”. the show starts with the host selecting (not necessarily randomly) a pool of n potential contestants from the audience. these potential contestants are carefully sequestered before the host proceeds to perform a simple stochastic experiment with n equiprobable outcomes oi (i = , . . . , n): flipping coins, rolling fair dice, spinning a roulette wheel, drawing numbered balls from a bingo cage, drawing cards from a deck, etc. different stochastic devices can be used in different versions or different episodes of the show. depending on the outcome of the experiment, the host then calls up, one by one, one or more of the n potential contestants to become actual contestants. each contestant is given a certain amount of money, say a thousand dollars, to place a bet, at even odds, on one of the n possible outcomes of the experiment the host just performed (that very experiment, not a repetition of it). if they are right, they go home with two thousand dollars; if they are wrong, they go home empty-handed. if contestants were randomly selected from the initial pool of n candidates, their chances of winning the bet would be /n regardless of which outcome oi they choose to put their money on. this probability is simply determined by symmetries of the physical object(s) used in the stochastic experiment. as long as he or she does not know anything about the selection procedure, a contestant’s degree of belief that the outcome was oi should be /n for all i. in bayesian terms, these should be his or her prior degrees of belief or priors for short: pr(oi) = n . ( ) however, in our game show, the selection procedure is anything but random and all candidates know that it is not. here is how it works. at the beginning of the show the candidates are divided into groups assigned to different outcomes. the sizes of these groups will be different for different outcomes. the candidates are told the sizes of the groups for all outcomes, but they are not told in which group they are. candidates become contestants if and only if they happen to be in the group for the actual outcome of the stochastic experiment. the host will call up all members of this group, one by one, to place their bet. to make sure that a candidate, when selected as a contestant, knows neither the outcome of the stochastic experiment nor whether any other candidates have already been called up as contestants, all of the candidates are put into individual soundproof booths after the host has explained to them how contestants will be selected but before he carries out the stochastic experiment (see figure ). when a booth’s door is closed, the candidate inside cannot detect in any way what is going on outside of it. the candidates are given the sizes of the groups for all outcomes before they are sent to their booths. each booth is equipped with a buzzer to let the candidate inside know that she has been selected as a contestant. the candidate-turned-contestant then leaves her booth, closes the door behind her, places the bet, and finds out whether she lost or won. unless she is the final contestant, she is only allowed to watch the rest of the show from a place where the contestants coming after her cannot see or hear her (or detect her presence in any other way). once all members of the group of candidates from now on, we will refer to actual contestants simply as contestants and to potential contestants as candidates. the restriction to bets at even odds can be relaxed but this would unnecessarily complicate the analysis. philosophies , , of selected as contestants have placed their bets, the remaining candidates are allowed to leave their booths and the show is over. figure . game show with monty hall, eight potential contestants, eight soundproof booths and a lottery ball machine as the stochastic device (drawing by laurent taudin). how can the candidates take advantage of the information they are given about the selection of contestants to improve their chances of winning their bets when selected as a contestant? let ni be the number of candidates in the group assigned to the outcome oi. these ni’s can be any non-negative integers that add up to the total number of candidates n. of course, the number of candidates will itself be a number chosen by the producers of the show. note that one or more ni’s can be zero. if nj = and oj happens to be the result of the stochastic experiment, no candidates will become contestants. that is not a problem. the host can simply repeat the stochastic experiment until he gets an outcome ok for which nk = . we can think of the instances in which the stochastic experiment produces a result oj, for which nj = as runs of the game where the game is over before contestants are called to the stage. the candidates can use bayes’s rule to update the priors in equation ( ) to take into account the information they are given about how candidates are selected to become contestants and use their posterior degrees of belief (or posteriors for short) when deciding which outcome to put their money on if and when actually selected as a contestant. they can do this updating as soon as they have been given the group sizes ni, even though their beliefs do not really matter unless and until they become contestants (see figure ). we will first do this bayesian updating for the simple case in which the stochastic experiment is a single coin toss. we then generalize the results to arbitrary stochastic experiments with n equiprobable outcomes. for a single toss of a fair coin, we have n = , o = h, o = t, n = nh , n = nt , n = nh + nt . ( ) philosophies , , of h and t stand for ‘heads’ and ‘tails’, respectively. nh and nt are the number of candidates in the groups for heads and tails, respectively. these should add up to the total number of candidates, n. the prior degrees of belief for any candidate that the coin will come up heads or tails, respectively, are: pr(h) = pr(t) = . ( ) we need to calculate the posteriors pr(h | a) and pr(t | a), where a stands for actual as opposed to potential contestant and is defined as a = i, a candidate, have been selected as a contestant, aware of the protocol for selecting candidates to become contestants. figure . a potential contestant in our game show sitting in her booth, contemplating what to do when chosen as an actual contestant (drawing by laurent taudin). because we have equal priors, we can use the simple version of bayes’s rule to calculate the posteriors: pr(h | a) = pr(a | h) pr(a | h) + pr(a | t) , pr(t | a) = pr(a | t) pr(a | h) + pr(a | t) . ( ) the evaluation of the posteriors thus comes down to the evaluation of the so-called likelihoods pr(a | h) and pr(a | t). one might be tempted to set pr(a | h) = pr(a | t) = / on the argument that the probability of any candidate being selected as a contestant is / , regardless of the outcome of the coin toss. in that case, we would also have pr(h | a) = pr(t | a) = / . we would be ignoring the information, however, that different numbers of candidates will become contestants depending on the outcome these formulas follow from the general multiplication rule for the probability of a conjunction of two outcomes, the law of total probability, and the equiprobability of h and t. the general multiplication rule allows us to write the probability of finding both h and a in two equivalent ways: pr(h & a) = pr(h) pr(a | h) = pr(a) pr(h | a). as long as none of these probabilities are zero, it follows that pr(h | a) = ( pr(a | h)/pr(a) ) pr(h). the law of total probability allows us to write pr(a) = pr(a | h) pr(h) + pr(a | t) pr(t). inserting this into the expression for pr(h | a) and using that pr(h) = pr(t), one arrives at the first equation in equation ( ). starting from pr(t & a) and proceeding the same way, one arrives at the second equation in in equation ( ). philosophies , , of of the coin toss, which is part of the statement a. that information thus also needs to be taken into account. if the coin came up heads (h) and the candidate is selected as a contestant (which is entailed by a), she must be one of the members of the group for heads. thus, the likelihood pr(a | h) is equal to the probability that she belongs to that group. great precautions have been taken to make sure that, as far as she can tell, she could be any one of the n candidates. the probability that she (or any other candidate) belongs to the group for heads is therefore simply the number of candidates nh in that group divided by the total number of candidates n. a similar argument can be given for pr(a | t). hence, pr(a | h) = nh n , pr(a | t) = nt n . ( ) inserting these expressions in equation ( ), we arrive at pr(h | a) = nh nh + nt = nh n , pr(t | a) = nt nh + nt = nt n . ( ) these posteriors replace the equal priors in equation ( ). in the case of equal priors (we will see in section that we have to be more careful in the case of unequal priors), the procedure for selecting contestants from an initial pool of candidates thus has the effect of replacing the priors, determined by the symmetry of the coin, by posteriors determined by the choice of the sizes nh and nt of the two groups into which the initial pool of n candidates are divided. what equation ( ) shows then is that the producers of the show can basically change the (equal) priors to any posteriors they like. because the posteriors in equation ( ) only depend on nh and nt , candidates will already know as they are sitting in their booths waiting for the buzzer to go off, whether they will choose heads or tails, should they be called up as contestants. if nh > nt , they choose heads. if nt > nh , they choose tails. if nh = nt = n/ , they get no information that would increase their chances of winning their bet. for nh = n (or, similarly, nt = n), finally, the game becomes trivial: all contestants would be guaranteed to win. if the coin comes up heads, the host calls up all contestants; if it comes up tails, he just flips it again. the same conclusions can be reached when we conceive of probabilities in terms of relative frequencies rather than degrees of belief. imagine that this version of our game show (with the same coin, the same pool of n potential contestants, and the same numbers nh and nt ) is repeated x times (with x a very large integer). now, put yourself in the shoes of an arbitrary potential contestant. you expect to be selected as a contestant in about nh /n of the roughly x/ runs of the show in which the coin will come up heads and in about nt /n of the roughly x/ runs in which the coin will come up tails (if nh = or nt = the show will be over without any contestants being selected in roughly x/ runs and you will be selected as a contestant in the roughly x/ remaining runs). overall, you thus expect to be selected as a contestant in about nh n x + nt n x ( ) runs. because nh + nt = n, equation ( ) confirms that, overall, you expect to be selected as a contestant in about half of the x runs. however, equation ( ) also shows that, if nt > nh , you expect to be a candidate in runs where the coin comes up tails more often than in runs in which the coin here is a more formal statement of this argument. let gh (gt ) stand for “i, a candidate, have been put in the group associated with the outcome h (t)”. the law of total probability (cf. note ) then allows us to write: pr(a | h) = pr(a | h, gh) pr(gh) + pr(a | h, gt) pr(gt) = pr(gh) = nh n , where, in the last step, we used that pr(a | h, gh) = and pr(a | h, gt) = . philosophies , , of comes up heads. in other words, that you (or any other potential contestant) should use equation ( ) and set the probabilities pr(h | a) or pr(t | a) equal to nh /n < and nt /n > , respectively, is simply to take into account this sampling bias. these results can readily be extended to arbitrary stochastic devices with n equiprobable outcomes oi (i = , . . . , n). the prior degrees of belief for any candidate that the experiment will result in oi are pr(oi) = n . ( ) for each outcome oi, there will be ni ≥ potential candidates (the host will repeat the stochastic experiment until he gets an outcome oj for which nj = ). because we have equal priors, we can use the simple version of bayes’s rule to calculate the posteriors: pr(oi | a) = pr(a |oi) ∑nj= pr(a |oj) . ( ) the candidate’s knowledge about the selection procedure tells him or her that the likelihoods are given by (cf. equation ( ) and the reasoning leading up to it) pr(a |oi) = ni n . ( ) inserting this expression for the likelihoods on the right-hand of equation ( ), we see that equation ( ) generalizes to: pr(oi | a) = ni n . ( ) once again, we see that the protocol for selecting contestants from an initial pool of candidates has the effect of replacing (equal) priors (see equation ( )), determined by symmetries of the stochastic device used, by posteriors (see equation ( )) determined by the choice of the numbers ni, which are only subject to the requirement that they add up to n, the number of candidates we started out with. like equation ( ), equation ( ) can be seen as expressing a certain sampling bias. imagine that this version of our game show (with the same stochastic device, the same pool of n potential contestants, and the same set of numbers {ni}) is repeated x times (with x a very large integer). put yourself in the shoes of an arbitrary potential contestant in these x runs of the game. suppose there are m < n outcomes oj for which nj = . that means that in roughly m(x/n) runs of the game, no contestants are selected. in the remaining (n − m)(x/n) runs, you will be selected as a contestant in about ni /n of the roughly x/n runs in which the outcome of the stochastic experiment is oi. overall, you will thus be selected in about n ∑ i= ni n x n ( ) runs. because ∑ni= ni = n, equation ( ) confirms that you expect to be selected as a contestant in about x/n runs overall. however, equation ( ) also shows that, if nk > nl > , you expect to be a candidate in runs with outcome ok more often than in runs with outcome ol . in other words, once again (see note ), this follows from the rule of total probability. let gi stand for “i, a candidate, have been put in the group associated with the outcome oi .” we then have: pr(a |oi) = n ∑ j= pr(a |oi , gj) pr(gj) = ni n , where we have used that pr(a |oi , gj) = δij (where δij is the kronecker delta, defined as δij = for i = j and δij = for i = j) and pr(gj) = nj /n. philosophies , , of that you (or any other potential contestant) should use equation ( ) and choose a value other than /n for the probability pr(oi | a) is simply to take into account this sampling bias. . game-show proxy for the original version of the sleeping beauty problem our proxy for the sleeping beauty problem is a special case of the game show analyzed with malice aforethought in equations ( )–( ) in section . it is a version or episode of the show in which the stochastic experiment is a single toss of a fair coin. we analyzed this game show for an arbitrary number of candidates n divided into groups for heads and tails, containing nh and nt candidates, respectively. to turn this into a proxy for the sleeping beauty problem, we set n = (the minimum number of candidates for which this version of the show is non-trivial) and nh = . thus, the parameters nh , nt and n introduced in equation ( ) have the values: nh = , nt = , n = . ( ) candidates (potential contestants; cf. note ) are the analogues of potential awakenings. the one candidate selected to become a contestant if the coin comes up heads is the analogue of the one potential awakening of sleeping beauty that becomes an actual awakening if the coin comes up heads. the two candidates selected to become contestants after the coin comes up tails are the analogues of the two potential awakenings that become actual awakenings if the coin comes up tails. the drugging of sleeping beauty ensures that during subsequent awakenings she knows as little about preceding awakenings as any candidate emerging from his or her booth to become a contestant knows about other candidates in the game-show proxy for the sleeping beauty problem. it may seem that there is still an important difference between candidates or potential contestants and potential awakenings. it is easy to tell potential contestants apart: we could use their social security numbers (ssns), for instance. every potential contestant will presumably know, at all times, what his or her ssn is. how can we tell sleeping beauty’s potential awakenings apart? how can sleeping beauty herself tell her own potential awakenings apart? fortunately, these questions have easy answers. we can specify, for any potential awakening, at what time and on what date it will happen if it will happen at all (allowing ten minutes or so for each awakening). we then put a clock that displays both time and date in the room where sleeping beauty is awakened so that she can tell, every time she is woken up, which potential awakening has just become an actual awakening. just as we had no need to refer to a potential candidate’s ssn, we will have no need to refer to date and time of a potential awakening. the point is that, at least in principle, individuating potential awakenings is no more problematic than individuating potential contestants. this way of providing potential awakenings with a time stamp should not be conflated with the time stamps used in the standard version of the sleeping beauty problem. there sleeping beauty is told ahead of time that she will be woken up a second time on tuesday if the coin comes up tails. in that case, sleeping beauty, when awakened, can obviously not be allowed to find out what day of the week it is (at least not until she has answered the question what her degree of belief is that the coin came up heads). in our version, she is only told that two of the three potential awakenings (labeled by the time and date they will happen) will become actual awakenings if the coin comes up tails. she is not told which two. in that case, the date and the time she is awakened are as irrelevant to sleeping beauty’s assessment of her degree of belief that the coin came up heads as the ssn of a potential contestant in our game-show proxy is to his or her calculation of the posteriors pr(h | a) and pr(t | a) (see equations ( )–( )). our substitution of ‘potential/actual contestants’ for ‘potential/actual awakenings’ likewise suggests that the notion of “self-locating beliefs” invoked by elga [ ] is irrelevant to the solution of the sleeping beauty problem. philosophies , , of sleeping beauty has no reason to doubt that the coin used to determine whether she will be woken up once or twice is fair. in other words, her prior degree of belief that the coin will come up heads should be pr(h) = . ( ) what should sleeping beauty’s degree of belief be, once she is woken up, that the particular toss of this coin that decided how many times she would be awakened resulted in heads? in bayesian terms, what is her posterior pr(h | a)? here a (which, as before, stands for actual as opposed to potential) is defined as a = i, sleeping beauty, have been awakened, aware of the protocol governing which of my potential awakenings become actual awakenings. with this reinterpretation of a and using the values of the parameters in equation ( ), we can use the first half of equation ( ) for sleeping beauty’s posterior degree of belief that the coin came up heads: pr(h | a) = nh n = . ( ) this follows directly from equation ( ) for the likelihoods pr(a | h) and pr(a | t). because this is the crux of the matter, we transfer the reasoning leading up to equation ( ) back to the sleeping beauty problem (see also note ). we do so for arbitrary values of nh and n. if the coin came up heads (h) and she has been awakened aware of the protocol for selecting awakenings (a), sleeping beauty knows that her present awakening must be one of the nh potential awakenings that become actual awakenings if the coin came up heads. thus, the likelihood pr(a | h) is equal to sleeping beauty’s degree of belief that her current awakening is one of those nh potential awakenings. great precautions have been taken to make sure that sleeping beauty, when she awakes, has no way of telling whether her current awakening is one of the nh potential awakenings should the coin come up heads or one of the nt potential awakenings should the coin come up tails. the probability that her current awakening is one of the former is therefore simply the number nh of such potential awakenings divided by the total number n of all potential awakenings. in section , we noted that the monty hall problem becomes more intuitive if the number of doors is increased. the solution to the sleeping beauty problem likewise becomes more intuitive if the number of potential awakenings or, in our game-proxy for the problem, the number of potential contestants is increased. instead of the values in equation ( ), we choose nh = , nt = , n = . ( ) in this case, equation ( ) tells us that sleeping beauty’s degree of belief that the coin came up heads plummets from its initial value of / to just / . like equation ( ) and equation ( ), equation ( ) can be seen as expressing a certain sampling bias. imagine that we repeat the experiment with sleeping beauty x times where x is some very large integer. in the roughly x/ runs in which the coin comes up heads, the total number of awakenings of sleeping beauty will be nh(x/ ). in the roughly x/ runs in which the coin will come up tails, the total number of awakenings will be nt(x/ ). in all runs combined, the total number of awakenings will, thus, be about nh(x/ ) + nt(x/ ) = n(x/ ). if nt > nh , more of these awakenings occur during runs in which the coin comes up tails than during runs in which the coin comes up heads. that sleeping beauty uses equation ( ) to set the probability pr(h | a) equal to nh /n = is simply to take into account this sampling bias. equation ( ) shows that, as long as our game show can be used as a proxy for the sleeping beauty problem, the thirders are right and the halfers are wrong. however, there is a simple way of reconciling philosophies , , of the two positions. once again, imagine that the experiment with sleeping beauty is repeated many times. ask sleeping beauty to answer the following pair of questions: question # : what is the probability that in an arbitrarily chosen run the coin comes up heads? answer: / . question # : what is the probability that an arbitrarily chosen awakening happens during a run in which the coin comes up heads? answer: nh /n (which works out to / for the values given in equation ( )). one can debate—and commentators have (see notes and )—whether question # or question # is the more natural way of interpreting the question in the original sleeping beauty problem and whether the problem doesn’t become trivial once you accept that halfers and thirders are just interpreting it differently. we will not get into those debates. we simply note that, although both questions are relevant to our game-show proxy (the answer to question # presupposes the answer to question # ), it is the second question that makes this game show and others like it intrinsically interesting or, at least, amusing to contemplate. . switch or stay? sleeping beauty on monty hall suppose that sleeping beauty is a contestant in a special episode of monty hall’s “let’s make a deal”. monty asks her to choose between doors d , d and d . behind one, he tells her, are two checks for a thousand dollars each; behind the other two is a goat. sleeping beauty chooses d . monty offers her the usual deal but with a twist. the twist is that he will only open one of the other doors (as usual we assume that monty knows which door has the checks behind it and that he will always open a door with a goat behind it) and give her the opportunity to switch after she’s been put under and woken up, possibly twice (in which case he will have to administer an amnesia drug the first time). every time she is awakened she is offered the same deal and monty hall will open one of the doors (not necessarily the same one each time) and offer her to switch. if sleeping beauty was right the first time and the checks are behind d , she will be woken up twice. if she was wrong the first time and the checks are behind d or d , she will only be woken up once. that she might have to be drugged once, monty tells her, is well worth it, as she will get one of the checks each time she picks the right door and could, thus, conceivably walk away with two thousand dollars. sleeping beauty takes the deal. when awakened, should she switch doors, should she stay with the one she originally picked, or should she be indifferent between switching and staying? the special episode of “let’s make a deal” with the three stooges in section is essentially our game-show proxy for this sleeping beauty on monty hall problem. the only difference is that instead of being made to take a nap backstage like the three stooges, our potential contestants will all be put in booths, like the ones that we used in the game show introduced in section . figure illustrates this particular format of the new game show. as in section , we assume the three candidates initially pick d . they are now divided into two groups. two of them are assigned to d , one of them is assigned to the other two doors. this makes the format of the game show significantly different from the one we introduced and analyzed in section . there all candidates were assigned to one of n equiprobable outcomes oi. in this case, they are assigned to non-equiprobable outcomes. this means that we can no longer use the simple form of bayes’s rule (for equal priors). we need to use the general form (for unequal priors). other than that, however, the analysis is completely analogous to the analysis in section . we have two (non-equiprobable) outcomes, this way of reconciling the positions of halfers and thirders follows groisman [ ]: “[a]n automatic device tosses a fair coin, if the coin lands ‘tails’ the device puts two red balls in a box, if the coin lands ‘heads’ it puts one green ball in the box. the device repeats this procedure a large number of times . . . the core of the whole confusion is that we tend to regard [the probability that] ‘a (one) green ball is put in the box’ and [the probability that] ‘a green ball is picked out from the box’ as equivalent” ([ ], p. ). philosophies , , of d = checks behind door # , not-d = checks not behind door # . ( ) the priors are: pr(d ) = , pr(not-d ) = . ( ) we have three candidates divided into two groups (one of two, one of one) assigned to these two outcomes: nd = , nnot-d = , n = nd + nnot-d = . ( ) figure . monty hall opens one of the doors with a goat behind it for one of the contestants in an episode of “let’s make a deal” with a twist inspired by the sleeping beauty problem (drawing by laurent taudin). the likelihoods are (cf. equation ( ) and the reasoning leading up to it): pr(a | d ) = nd n = , pr(a |not-d ) = nnot-d n = , ( ) where a is defined as in section as “i, a candidate, have been selected as a contestant, aware of the protocol for selecting candidates to become contestants”. the posterior pr(d | a) is given by (the general form of) bayes’s rule (cf. note ): pr(d | a) = pr(a | d ) pr(d ) pr(a | d ) pr(d ) + pr(a |not-d ) pr(not-d ) . ( ) the posterior pr(not-d | a) has the same denominator but pr(a |not-d ) pr(not-d ) in the numerator. from equations ( ) and ( ), we see that pr(a | d ) pr(d ) = pr(a |not-d ) pr(not-d ) = , ( ) which means that pr(d | a) = pr(not-d | a) = . ( ) philosophies , , of thus, the sampling bias introduced by our peculiar procedure of selecting contestants from an initial pool of candidates wipes out the advantage of switching doors a contestant would have had in a regular episode of “let’s make a deal”. replacing the three potential contestants by three potential awakenings, we conclude that sleeping beauty should be indifferent between staying with the door she initially picked and switching to the one other door that remains unopened. of course, we can just as easily create a version of the sleeping beauty on monty hall problem in which she increases her chances of picking the right door from / to / by staying. to do that, we replace the values of nd , nnot-d and n in equation ( ) by nd = , nnot-d = , n = . ( ) in this case, we need, say, the jackson five rather than the three stooges (and four checks of a thousand dollars). inserting the numbers in equation ( ) into equation ( ) for the likelihoods, we find pr(a | d ) = nd n = , pr(a |not-d ) = nnot-d n = . ( ) inserting equation ( ) for the priors and equation ( ) for the likelihoods into equation ( ) for the posterior pr(d | a), we find pr(d | a) = , pr(not-d | a) = . ( ) in this case, our contestants and, hence, sleeping beauty should stay with d . these results can easily be generalized from to n doors (in which case we will need still more checks and monty hall will have to open n − doors before offering the contestant to switch). we will do this only for the case that contestants (and, hence, sleeping beauty) should be indifferent between switching and staying. in that case, we need n = n candidates (and n − checks). suppose they collectively pick the jth door. we can now basically repeat the steps in equations ( )–( ). the two (non-equiprobable) outcomes are: dj = checks behind j th door, not-dj = checks not behind j th door. ( ) the priors are: pr(dj) = n , pr(not-dj) = n − n . ( ) the sizes of the groups assigned to these two outcomes are: ndj = n − , nnot-dj = . ( ) the likelihoods are: pr(a | dj) = ndj n = n − n , pr(a |not-dj) = nnot-dj n = n . ( ) the posterior pr(dj | a) is: pr(dj | a) = pr(a | dj) pr(dj) pr(a | dj) pr(dj) + pr(a |not-dj) pr(not-dj) . ( ) the posterior pr(not-dj | a) has the same denominator, but pr(a |not-dj) pr(not-dj) in the numerator. from equations ( ) and ( ), we see that pr(a | dj) pr(dj) = pr(a |not-dj) pr(not-dj) = n − n , ( ) which means that philosophies , , of pr(dj | a) = pr(not-dj | a) = . ( ) in other words, contestants in this game (and sleeping beauty in the variation on the sleeping beauty problem for which this game show is a proxy) should be indifferent between staying and switching. the design of a game-show proxy for this variation on the sleeping beauty problem nicely illustrates how such game shows can be used to get a better handle on such puzzles. . switch or stay? a variation on the : lifeline in “who wants to be a millionaire?” in this section, we introduce and analyze one last variation of the game shows that we used in sections – to analyze the sleeping beauty problem and generalizations of it. in those sections, the priors in bayes’s theorem were determined by symmetries of various physical systems. all else being equal, the odds of a fair coin landing heads or tails are / and one door is as likely as the other two to have the prize behind it. in the game show to be considered in this section, however, the priors will be degrees of belief that do not reflect such symmetries. in sections and , we showed that our analysis works regardless of whether we think of probabilities as relative frequencies or as degrees of belief. this remains true in this section. there is a simple way to represent some agent’s degree of belief in some proposition a in frequentist terms. imagine we ask our agent to place a bet (at even odds) on a or not-a. if she reports her degree of belief in a to be ≤ x ≤ , she should be prepared to spin a wheel of fortune with a pie chart printed on it with a portion πx corresponding to a and a portion π( − x) corresponding to not-a and pick a or not-a based on where the marker of this wheel of fortune lands. the specific game show we will examine in this section was inspired by the : lifeline of the popular tv show “who wants to be a millionaire?”. our variation on this show calls for groups of at least three contestants. here is how it works. regis philbin, the host of the most successful incarnation of “who wants to be a millionaire?”, asks the group of contestants some trivia question and gives them four answers to choose from. they collectively have to pick one. regis informs them that they have been divided into two groups ahead of time. they are told the sizes of these two groups, < nr < n, < nw < n, with nr + nw = n and nr = nw ( ) (where the subscripts ‘r’ and ‘w’ stand for ‘right’ and ‘wrong’, respectively), but not in which group they are. regis then asks all contestants to go to one of the soundproof booths familiar from the game shows examined in sections – . if the answer they chose is right, regis explains to the contestants before they all go into their booths, he will bring back, one by one, all those in the group with nr contestants; if their initial answer is wrong, he will bring back, one by one, all of those in the group with nw contestants. every time regis brings back a contestant, he eliminates two of the three answers not initially chosen (not necessarily the same two for every contestant) and offers the contestant a choice between the answer i initially chosen and the one remaining alternative answer not-i. as should be clear from the analysis in section (and as we will verify in detail below), a contestant will be more likely to stick to i than she otherwise would have been if nr > nw and more likely to switch to not-i if nr < nw. contestants whose final answer is wrong and contestants who are not called back at all are eliminated from the game. regis then repeats the procedure described above with a new trivia question and a reduced number of contestants. he keeps repeating it until there is only one contestant left, who is then declared the winner of the game (when it gets down to two contestants, nr = nw = and the condition nr = nw is dropped). philosophies , , of which answer a contestant chooses when she is called back to give her final answer depends on the probabilities pr(i) and pr(not-i) she assigns to the answers i and not-i. unlike the doors in the monty hall problem, different answers will, in general, be assigned different initial probabilities. moreover, these probabilities will, in general, be different for different contestants. priors and posteriors in this case clearly represent degrees of belief rather than relative frequencies, even though, as we pointed out at the beginning of this section, they can still be interpreted either way. the posterior pr(i|a) is given by an equation that is similar to equations ( ): pr(i | a) = pr(a | i) pr(i) pr(a | i) pr(i) + pr(a |not-i) pr(not-i) , ( ) where a is defined as “i have been called back to give my final answer aware of the protocol determining which contestants are called back to do so”. using expressions similar to those in equations ( ) for the likelihoods, pr(a | i) = nr n , pr(a |not-i) = nw n , ( ) and inserting − pr(i) for pr(not-i), we can rewrite the posterior as: pr(i | a) = nr pr(i) (nr − nw) pr(i) + nw . ( ) as long as nr = nw and pr(i) is not equal to or , the posterior differs from the prior. we now ask what the minimum value of pr(i) must be for a contestant to choose the answer i over the answer not-i. thus, we are looking for values of the prior such that the posterior is greater than . equation ( ) tells us that pr(i | a) > as long as pr(i) > nw n . ( ) thus, the contestant should ask herself, factoring in that there are only two answers left but not how regis selects the contestants he calls back to give their final answer, what her degree of belief pr(i) contestants get two pieces of evidence affecting their degree of belief in the hypothesis h that i is the right answer: e , which says that two answers are wrong, and e , which says that, depending on what the right answer is, all those in the group with nr contestants or all those in the group with nw contestants are called back to give their final answer. bayes’s rule says that for some hypothesis h and two pieces of evidence e and e the posterior pr(h|e &e ) is given by pr(h|e & e ) = pr(e & e |h)pr(h) pr(e & e ) , where the prior pr(h) is the degree of belief in h before the bayesian agent found out about e and e . the right-hand side of this equation can be rewritten either as pr(e |h)pr(e |h & e )pr(h) pr(e )pr(e |e ) = pr(e |h & e )pr(h|e ) pr(e |e ) or as pr(e |h)pr(e |h & e )pr(h) pr(e )pr(e |e ) = pr(e |h & e )pr(h|e ) pr(e |e ) . this shows that the order in which a bayesian agent updates on e and e does not matter. whether this is or should also be true for a contestant in our game show evaluating the hypothesis h under consideration here in light of the two specific pieces of evidence e and e is a question that we leave open (one could likewise wonder whether it does or should remain true if e and e are the outcomes of measurements of two observables represented by non-commuting operators in quantum mechanics). we only analyze the updating on e in bayesian terms. thus, the prior pr(i) in this application of bayes’s rule is in the notation of this footnote, pr(h|e ), with h = i. substituting x ≡ pr(i) (with < x < ) on the right-hand side of equation ( ) and asking when the resulting expression is greater than , we find that nr x > ((nr − nw) x + nw) or (nr + nw) x > nw , from which equation ( ) follows. from equations similar to equations ( )–( ), it follows that pr(not-i | a) > as long as pr(not-i) > nr /n. philosophies , , of is that i is the correct answer. if pr(i) > nw /n, she should stay with i. if pr(i) < nw /n, she should switch to not-i. if pr(i) = nw /n, she should be indifferent between staying and switching. thus, the producers of the show can ensure that the selection mechanism boosts a value as low as /n for pr(i) to a value of for pr(i | a) by choosing nw = and nr = n − . by choosing nr = and nw = n − , they can likewise ensure that pr(not-i) = /n gets boosted to pr(not-i | a) = . “who wants to be a millionaire?” could thus get a new lease on life by borrowing some ideas from sleeping beauty and monty hall. . conclusions: game shows and pedagogy as one of us can attest on the basis of actual teaching experience (cf. note ), the game shows introduced and analyzed in this paper make for effective pedagogical tools in introductory undergraduate courses in philosophy of science. they nicely illustrate how one can get a handle on an easy-to-grasp yet non-trivial problem by (a) modeling it in a way that avoids one of its most confusing aspects (the problem of “self-locating beliefs”, which evaporates once awakenings are replaced by contestants); (b) varying the parameters of the model (the solution is much easier to see for larger numbers of awakenings/contestants); and, (c) recognizing that the problem is just one in a much broader class of similar problems (the coin flip can be replaced by rolling dice, drawing a ball from a bingo cage, spinning a roulette wheel, or what have you). our solution of the sleeping beauty problem also provides an instructive example of applying bayes’s rule. in this particular application, the main challenge is to articulate exactly what one should conditionalize on when updating one’s degree of belief. using different versions of our game show, we highlighted the difference between the simple and general form of bayes’s rule (for equal and unequal priors, respectively [cf. note ]). we analyzed all versions of our game show both in terms of degrees of belief and in terms of relative frequencies, thus helping students to appreciate the difference between these two conceptions of probability in some concrete examples. given these pedagogical benefits, we hope that other instructors will try out these game shows in their classes. if they do, we hope that they and their students will have as much fun with them as we have had. author contributions: both authors contributed equally to the conceptualization, formal analysis and writing of this paper. both authors have read and agreed to the published version of the manuscript. funding: the work of m.j. was supported by the alexander von humboldt foundation and jürgen renn’s department at the max planck institute for history of science in berlin. acknowledgments: we are grateful to pradeep mutalik [ ], whose article inspired our paper. we want to thank john norton for helpful comments on an earlier draft, jack van sambeek and ryan bowers for catching a serious error in section , and laurent taudin for his lovely illustrations of our piece. we thank an anonymous referee for this journal for restoring our faith in the refereeing process and for suggesting the addition of notes and . we also thank rose adams, jamie debruyckere, terrance gray, scott spicer, charlie heinz, and again laurent taudin for their contributions to the youtube video related to this paper (see footnote ). we dedicate this paper to the memory of monty hall ( – ) and regis philbin ( – ), who were both still alive when we wrote the first draft of this paper. conflicts of interest: the authors declare no conflict of interest. references . elga, a. self-locating belief and the sleeping beauty problem. analysis , , – . [crossref] . lewis, d. sleeping beauty: reply to elga. analysis , , – . [crossref] . cisewski, j.; kadane, j.b.; schervish, m.j.; seidenfeld, t.; stern, r. sleeping beauty’s credences. philos. sci. , , – . [crossref] . schulmann, r.; kox, a.j.; janssen, m.; illy, j. (eds.) the collected papers of albert einstein, volume , the berlin years: correspondence – ; princeton university press: princeton, nj, usa, . . bradley, d. bayesianism and self-locating beliefs. ph.d. thesis, stanford university, stanford, ca, usa, . http://dx.doi.org/ . /analys/ . . http://dx.doi.org/ . /analys/ . . http://dx.doi.org/ . / philosophies , , of . mcgrayne, s.b. the theory that would not die: how bayes’ rule cracked the enigma code, hunted down russian submarines, & emerged triumphant from two centuries of controversy; yale university press: new haven, ct, usa, . . hitchcock, c. beauty and the bets. synthese , , – . [crossref] . groisman, b. the end of sleeping beauty’s nightmare. br. j. philos. sci. , , – . [crossref] . mutalik, p . why sleeping beauty is lost in time. quanta magazine, march . available online: https: //www.quantamagazine.org/ -why-sleeping-beauty-is-lost-in-time/ (accessed on april ). c© by the authors. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /). http://dx.doi.org/ . /b:synt. . .c http://dx.doi.org/ . /bjps/axn https://www.quantamagazine.org/ -why-sleeping-beauty-is-lost-in-time/ https://www.quantamagazine.org/ -why-sleeping-beauty-is-lost-in-time/ http://creativecommons.org/ http://creativecommons.org/licenses/by/ . /. warm-up exercise: the three stooges on monty hall introduction: monty hall and sleeping beauty game-show proxies for (variations on) the sleeping beauty problem game-show proxy for the original version of the sleeping beauty problem switch or stay? sleeping beauty on monty hall switch or stay? a variation on the : lifeline in ``who wants to be a millionaire?'' conclusions: game shows and pedagogy references mazur pesic.qxd on mathematics, imagination and the beauty of numbers the harvard community has made this article openly available. please share how this access benefits you. your story matters citation mazur, barry c., and peter pesic. . on mathematics, imagination & the beauty of numbers. daedalus ( ): - . published version doi: . / citable link http://nrs.harvard.edu/urn- :hul.instrepos: terms of use this article was downloaded from harvard university’s dash repository, and is made available under the terms and conditions applicable to other posted material, as set forth at http:// nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of- use#laa http://osc.hul.harvard.edu/dash/open-access-feedback?handle=&title=on% mathematics,% imagination% and% the% beauty% of% numbers&community= / &collection= / &owningcollection / &harvardauthors=b a f ba e a c a b ea d &departmentmathematics http://nrs.harvard.edu/urn- :hul.instrepos: http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#laa peter pesic: many intelligent people only see in mathematics a wasteland of dreary formalism, a mind-numbing ex- panse of theorems and proofs expressed in very abstract language. doubtless this is partly due to the way it is taught, but such teaching is almost universal, the product of good intentions and much effort. the disconnection between the inner, lived world of mathematicians and the mainstream of intelligent people is very deep, despite the sensual charac- ter of mathematics that you describe so well in your recent book, imagining num- bers: (particularly the square root of minus ½fteen). this raises a hard question: how –if at all–can this living world of math- ematics become accessible? barry mazur: i can’t answer that question, but i can offer some com- ments. a person’s ½rst steps in his or her mathematical development are ex- ceedingly important. early education deserves our efforts and ingenuity. but also here is a message to any older per- son who has never given a thought to mathematics or science during their school days or afterwards: you may be ready to start. starting can be intellectu- ally thrilling, and there are quite a few old classics written in just the right style to accompany you as you begin to take your ½rst steps in mathematics. i’m thinking, for example, of the old t. c. mits series, or tobias dantizg’s wonder- ful number: the language of science, or lancelot hogben’s mathematics for the millions. moreover, one should not be dismayed that there are many steps– there is no need to take them all. just enjoy each one you do take. bill thurston, a great geometer, uses the word ‘tall’ to describe mathematics: math is a tall subject in the sense that skyscrapers are tall. that is, one piece of mathematics lies on top of a prior piece of mathematics and lies under the next piece of mathematics, etc. to get to the dædalus spring dialogue between barry mazur & peter pesic on mathematics, imagination & the beauty of numbers barry mazur, a fellow of the american academy since , is the gerhard gade university profes- sor at harvard university, where he has taught for over four decades. he has done research in many aspects of pure mathematics and is the author of “imagining numbers: (particularly the square root of minus ½fteen)” ( ). peter pesic is a tutor and musician-in-residence at st. john’s college in santa fe, new mexico. he is the author of “labyrinth: a search for the hid- den meaning of science” ( ), “seeing dou- ble: shared identities in physics, philosophy, and literature” ( ), “abel’s proof: an essay on the sources and meaning of mathematical un- solvability” ( ), and “sky in a bottle” ( ). © by the american academy of arts & sciences mazur pesic.qxd / / : pm page ½ftieth story you must traverse all the prior forty-nine, and in the right order. i like this image, but would want to insist that it may be more of a gaudi-esque structure, with a wide choice of alternate staircases joining and crossing so if you are ever uncomfortable with one route –if the risers are too high, or not high enough–there are other, more accom- modating stairwells. and besides, even the view from the ½rst story is a marvel. pp: what is your earliest memory of mathematics? bm: the very earliest was when i was seven or eight years old. my father, who was always fascinated with numbers, would shower me with arithmetical queries like, what is the number that when you double it and add one gives you eleven? i don’t think i was particu- larly adept at ½nding the answers to these problems, but i did love them. my method was, of course, trial and error. then, after an especially long barrage of such queries, my father smiled at me and said, “i’ll tell you a secret. here is how you can do these problems more quick- ly.” the “secret” he imparted to me was to invoke the magical x of algebra, re- state the problem in the language of al- gebra, and then to simplify the algebraic sentence, where by simplify he meant solve for x. that x became, after sim- pli½cation, an actual number, which as- tonished me. my father also insisted on the ritual palindrome of analysis and synthesis, in the sense that once the val- ue of x was found, i was to redo the steps of the derivation in reverse order to check that the number i came up with for x really worked. i suppose that i had an especially liter- al mind, for i actually did think that this information was some sort of secret. a family secret, perhaps, as there might be family secret recipes for particular dishes. i remember being stunned a few years later in a math class, for somehow the teacher had gotten wind of this se- cret and seemed to be in the process of explaining it to the entire class. pp: as you confronted this secret, how did it act on you, and especially on your imagination? bm: i think it acted more on my sense of wonder than on any concrete imagin- ings. to work out those simple queries (e.g., what is that number which when you double it and add one you get eleven?) is rather like seeing a concrete visual image develop out of a blank nothing on photo- graphic paper in a darkroom tray. you start with something you deemed x, and at the end of the process you discover x to be concrete, some particular number. there is a sense of power in this (as you and i know, the early algebraists were very aware of this unexpected power) and in having this power be ‘secret’ as well. what could be more enticing? when i realized this was part of a much larger common heritage, i wasn’t sad: it made it that much larger a clubhouse. my early fascination was that out of pure thought, starting with nothing, some- thing concrete emerges. i remember, a good deal later, being still struck by the equation nothing + thought = something. about a year before high school, i be- came an avid reader of popular books about electronics and math. when i was building radio receivers (maladroitly, for the most part) i had the idea of deriving maxwell’s equations by pure thought. how this was going to be accomplished was not so clear, for it is too simple- minded to imagine that some saint anselmian strategy (making the sole assumption, for example, that the laws dædalus spring dialogue between barry mazur & peter pesic mazur pesic.qxd / / : pm page governing radio transmission were the “most perfect laws”) would lead to laws none other than maxwell’s. but when i was in high school i had complete faith that such a derivation was possible. pp: in those early days, to what extent was your access to mathematics mediat- ed through physical devices like radios or through visualization, as in electronic schematics? i am thinking of einstein’s insistence that he was always primarily a visual thinker, not an abstract one. bm: let me respond to this question go- ing from the back to the front. i don’t think i ever deal with things that are ab- stract. to be more explicit, i don’t like the word ‘abstract’ except as a compar- ative term, even though lots of mathe- maticians use it in a way that reminds me of the dangling comparatives that sometimes show up in ordinary speech. texts and courses have titles like abstract algebra, etc.; my impulse when i see these is to wonder, “abstract compared to what?” to put it another way, think of the tactic of taking a concept that has arisen in one context and then stripping it from that particular context. for in- stance, start with euclidean geometry in the full expression of its geometric intu- ition and with all its axioms, then strip a few axioms from the list and consider the structure that ensues, with either no concrete realization in mind, or at least as an entity of thought separate from any geometric realization. this is a situation where i believe it is helpful to say that one has abstracted a structure, separat- ing it from its habitual concrete and vi- sualizable context. even so, i’m hesitant to use such a lat- inate word as ‘abstract’ for this mode of thought. aristotle, for example, has at least two different ways of referring to the activity of abstraction: he employs the verb aphairein, which indeed means to ‘abstract,’ to ‘take away.’ but at times, as in book of the metaphysics, he em- ploys the more explanatory phrase “to take that which does not exist in separa- tion and consider it separately”–a de- scription that has, to my mind, a less scary aspect. but once the concept has been, as people say, abstracted, or once it is, as aristotle would say, taken sepa- rately, if one is to deal effectively with it, one must floodlight it with intuitions of some sort or other. if one is really think- ing about this ‘abstracted’ concept and working with it seriously, it will become utterly as concrete as any other concept. of course, one may have to homegrow the appropriate intuitions to deal seri- ously with it. electronics, or at least circuitry at the primitive level that i used as a kid, was saturated with concretizing analogies. as i’m sure you know, kirchhoff’s law and ohm’s law are made vivid by a sim- ple analogy to hydraulics–plumbing, if you wish. and maxwell, when he sought to give vocabulary for the energy in elec- tromagnetic ½elds, went surprisingly further with this analogy: the somewhat mysterious displacement current that he denoted j (and that seemed so wonder- ful to me when i ½rst encountered it)–a marvelous concretization of ‘action at a distance.’ pp: what you are saying here is consis- tent with what you write in imagining numbers, where you seek felt correlates for an ‘abstract’ concept like i = √- . but now you are extending this view in a dar- ing way. what happens then in ‘abstract’ thinking on the level that you and other mathematicians pursue it, in which (at least for many intelligent people) there seems to be no trace of any sensual, con- crete content? dædalus spring mathematics, imagination & the beauty of numbers mazur pesic.qxd / / : pm page bm: i think that analogy is a powerful tool, and it can extend, inde½nitely, the range of what we are happy to call con- crete, or sensual. let us start with the truism that the stock-in-trade of poets is to concretize things by analogy. any snatch of poetry offers some illustration of this. consider, for example, these lines of yeats: “like a long-legged fly upon the stream / his mind moves upon silence.” here the equation is between something that is concrete/sensual and external (the “long-legged fly upon the stream”) and something that might ac- tually be even more intimately connect- ed to us, but much harder to catch and hold still: a curious interior state. mathematicians are constantly using analogy to expand the realm of what they hold to be concrete. the ubiquitous activity of generalizing, which is one of the staples of mathematical and scien- ti½c progress, is a way of analogizing. we start with a structure or concept we feel at home with (say, multiplication of or- dinary numbers), and we see a broader realm for which the same or at least an analogous structure or concept may pos- sibly make sense (say, think of composi- tion of transformations as a kind of mul- tiplication operation). we make our- selves at home with this more general concept, initially at least, by depending heavily on the analogy it has with the more familiar, less general concept. one genre of analogizing in mathe- matics is to deal with a problem that at ½rst does not seem to be geometric by recasting it in geometric language. for example, consider fredholm’s idea for ½nding the (unique) function that is the solution of a certain type of equation by translating the problem to that of ½nd- ing a ½xed point of a certain distance- shrinking transformation on a geometric space. pp: in your view, is there, then, any part of mathematics that is radically divorced from sensual intuition? what about number theory, where there is no geo- metric, hence visual, ½eld, at least at ½rst glance? bm: i don’t think there is any mathe- matics radically divorced from some kind of vivid intuition that illuminates it and ties it to the sensual. you say that number theory has no geometric, hence visual, ½eld at ½rst glance–but that is only at ½rst glance. for most practitioners of number theory these days, number theory is intensely geometric. in the late s and early s i was a geometer, a topologist, and the hook that got me fascinated with number theory was to understand that the set of integers . . . - , - , - , , + , + , + . . . has properties closely analogous to the three-dimensional sphere. strange as it may seem, the prime numbers are analo- gous to knots (closed non-self-intersect- ing loops) in the three-dimensional sphere. once you see this analogy you begin to see deeply instructive parallels between geometry and number theory. for example, the skew symmetry of the linking number of one knot relative to another is somehow formally related to what is known in number theory as quadratic reciprocity (a deep reciprocal relationship, initially discovered by gauss, that holds between any two prime numbers). this is hardly the only analogy that ties number theory to ge- ometry–there are so many that very often it is hard to classify a theorem as being in the one ½eld or the other. the connections here began as far back as in the works of abel, in that galois theory itself sits–ambiguous- ly–between geometry (the study of dædalus spring dialogue between barry mazur & peter pesic mazur pesic.qxd / / : pm page ½nite coverings of spaces) on the one hand, and algebra (the study of solutions of polynomial equations). this relation- ship was thoroughly understood by kro- necker and weber over a hundred years ago. the mathematical discipline of al- gebraic geometry already expresses the ineluctable joining of these ½elds. sixty years ago, andré weil dreamt up a striking way of very tightly controlling and counting the number of solutions of systems of polynomial equations over ½nite ½elds (this being a quintessentially number-theoretic problem) by surmis- ing that there must be a tool for number theory closely analogous to the basic to- pological theory that ef½ciently counts the numbers of intersections that one geometric subspace has with another subspace when both are contained with- in a larger ambient space. all this appa- ratus has now been set up and establish- es a vivid geometric mode of under- standing polynomials and systems of polynomials in any algebraic context; indeed, much of number theory is now very comfortably viewed as a piece of a smooth-working synthesis, usually re- ferred to as arithmetic algebraic geom- etry. this long-winded answer, then, is sim- ply to say that to many current research- ers, number theory is inseparable from geometry, and much mathematical work occurs in a realm that is–marvelously– a synthesis of the two. pp: but what about considerations in- volving higher dimensions than the three of common spatial experience? must we rely on analogies to that com- mon world? to what extent would that be possible without, perhaps, deluding ourselves that we are really understand- ing those more complex spaces, not just squashing them to ½t our limited senses? bm: but i think we are squashing them, and slicing them, to ½t our limited sens- es–or at least to ½t the limits that our senses are constrained to at present. and squashing them is a prelude to under- standing them. without some real in- novation, real insight, and exercise of imagination, you don’t even know how to begin any squashing procedure. squash how? any act of squashing takes work, and the work itself is what expands one’s intuition–expands the limits of our senses. let me remind you of some standard examples. the most immediate source of examples does not come from high dimensions, but is al- ready in our three-dimensional space of common experience. to visualize things well in three dimensions takes some ar- ti½ce. think of the repertoire: the top view, side view, front view, etc., of archi- tectural drawings; the mercator and other projections to render the globe flat; the cat scans and mris that make pictures of slices of three-dimensional bodies, these slice pictures being taken in various moving and rotating planes and then cleverly put together to render a more faithful understanding of the full three-dimensionality of the examined body. or think, if you wish, about that chair you are looking at, which you have only one view of (give or take a bit of the parallax of your two eyes and your mov- ing head), and whose utter three-dimen- sionality you are so at home with. in a way, all the arti½ces, as i called them, which work so well for us to sub- stantiate our common three-dimension- al experience, are there to be employed to bring higher dimensions into our ken as well. the special theory of relativity deals with four coordinates (x,y,z,t) usually referred to as ‘space-time,’ and the usual way of thinking graphically about anything happening in this four- dimensional geometry is as a movie of dædalus spring mathematics, imagination & the beauty of numbers mazur pesic.qxd / / : pm page three-dimensional slices changing in time. but there are other modes of squash- ing the thing down to our limited senses, thereby, in effect, extending those senses. for example, one might envision the four-dimensional space as a planar (i.e., two-parameter) family of planes that, taken all together, ½ll out four- dimensional space: every point in four- dimensional space will lie on exactly one of these two-dimensional slices. the fun here is that you need a two-dimensional collection of these two-dimensional slices to sweep out the entirety of four- dimensional space: + = , after all. you then have the option of thinking of (or visualizing, if you wish) any geomet- ric object in four-dimensional space in terms of how it is diced by this proce- dure. this type of intuition is very well developed in people who do complex analysis. even this list understates the issue. one isn’t quite ½nished if i just give you a ½nite repertoire–a bag of tricks, so to speak, in the art of squashing–because at a point in one’s development of these intuitions, one actually sees more than the mere sum of tricks. one realizes that there is a certain unexpected pliability of spatial intuitions that makes spaces of any dimension equally accessible– equally accessible, and in certain re- spects (and here’s a surprise) more eas- ily accessible than lower-dimensional spaces. topologists understand very well that for certain important work, higher- dimensional spaces are simply easier than lower-dimensional spaces–there’s more room to move around! for example, the poincaré conjecture was ½rst proved by steve smale in the mid- s in dimensions equal to ½ve or more. it took well over a decade after that for it to be proved by michael fried- man in dimension four. dimension three is still open, although a russian mathe- matician, perelman, has recently an- nounced that he has a proof. the short answer here is that one will always try to reach out as far as one can with whatever intuition one has and squash as much as one can into it. doing this squashing has the effect of extending and improv- ing our intuition. pp: are there no spaces that are utterly alien to our intuition, only available through a kind of reasoning that is not accessible to our senses? bm: i want to think of our intuition as not an inert, unchanging resource, but rather as something that can expand when challenged, when exercised. and the mechanism that forces this expan- sion is analogy. so, are there spaces ut- terly alien to our intuition? all i can say is that i don’t think utterly. pp: but the very struggle of human imagination to extend itself so far past its common limits indicates that these spaces really may transcend our sensibil- ity. we struggle to grasp new mathemat- ical truths not just because it is hard to visualize them, but also because they de- fy our most deeply held presumptions. for instance, we try to visualize the in½nite-dimensional hilbert space of quantum theory using visual analogues, but a spinning ball is utterly unlike an electron with spin. at a certain point, doesn’t the visual and anthropomorphic fail just because we have gone beyond what we can visualize? and doesn’t symbolic mathematics then save us by allowing us to reason securely even when we can no longer see? bm: what you say is unassailable. but the full panoply of our mathematical intuitions–the intuitions that mathe- dædalus spring dialogue between barry mazur & peter pesic mazur pesic.qxd / / : pm page matics helps strengthen, and re½nes–is not limited to pure visualization or pure symbolic combinatorial processes or, for that matter, pure any one thing. i would say that the most powerful of our intuitions are combinations: a po- tent blending of visualization and artful algebra, of intrinsic canniness of estima- tion, and of all the intuitions that are the children of sheer experience–knowing when to approximate, when to insist on exact calculations, when to neglect some terms, when to pay the closest attention to them, when to rely upon an analogy, when to distrust it, and . . . well, i would not want to limit this list. but there are two things i would like to emphasize about the ingredients of the brew i just described. the ½rst is that these intuitions tend to amplify, to mag- nify, each other. the second is that these intuitions show up and are, in some form, perfectly available to anyone who tries their hand at understanding any piece of mathematics, however elemen- tary. now let’s return to your example of the in½nite-dimensional hilbert space that provides a model for quantum mechanical considerations. i think the notion of in½nite-dimensional hilbert space is a wonderful example of how algebra ampli½es the range of visualiz- ability of geometry. a hilbert space is, almost by formal de½nition, a space, of never mind how many dimensions, such that any two-dimensional plane in it has all the properties of the euclidean plane. you can think of it as being very, very visualizable in two-dimensional slices despite its immensity, along with a guarantee from hilbert that this very feature of it–visualizability in slices–is what is going to be most relevant. now once we (or initially, i suppose, hilbert) hit upon this idea, our basic intuitions regarding euclidean geome- try–the euclidean geometry of our high school days–become magically avail- able even in contexts where we would hardly have dared to imagine that visual- ization would have any relevance. the example you offer of electrons with spin modeled in terms of hilbert space is a great testimonial, precisely, to the manner in which visualization as an intuition can be ampli½ed and made more powerful by mathematical analo- gies. our comprehension of euclidean geometry is ampli½ed, thanks to hilbert, to be a useful thing in understanding even the most seemingly unvisual as- pects of atomic particles. pp: here you point to new possibilities that would surprise many people who consider themselves mathematically hopeless. perhaps they think themselves incapable of abstraction or manipulating formalism. you are telling them that, on the contrary, it is the sensual side they are missing. bm: living mathematics is in no way abstract, at least to the people who live it. intuitions can tie mathematics to the most concrete pictures, sensual experi- ences, and things that are immediate to all of us. there are always loads of alter- nate routes. if you are blocked at one route, no problem–try another. i believe this is the common understanding of just about everyone who practices math- ematics. mathematics is often taught without such connections, but there is no reason that it can’t be taught so that a student’s intuitions are fully engaged and exercised every step of the way. dædalus spring mathematics, imagination & the beauty of numbers mazur pesic.qxd / / : pm page balkan is beautiful: balkanism in the political discourse of tudman's croatia this is a repository copy of balkan is beautiful: balkanism in the political discourse of tudman's croatia. white rose research online url for this paper: http://eprints.whiterose.ac.uk/ / version: accepted version article: razsa, m. and lindstrom, n. orcid.org/ - - - ( ) balkan is beautiful: balkanism in the political discourse of tudman's croatia. east european politics and societies. pp. - . issn - https://doi.org/ . / eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ reuse unless indicated otherwise, fulltext items are protected by copyright with all rights 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articlebalkan is beautifuleast european politics and societies balkan is beautiful: balkanism in the political discourse of tudman’s croatia maple razsa and nicole lindstrom* this article examines the role of balkanist discourse in tu¦man’s croatia. todorova’s concept of balkanism provides a useful theoretical framework through which to explore the deployment of balkanist stereotypes against croatia by western leaders. balkanism also illuminates the ways in which croatians used many of these same balkan stereotypes to differentiate themselves from their neighbors to the south and east. through an exami- nation of croatian newspaper columns, government documents and speeches, and political cartoons from the s, this article analyzes how balkanist interpretations and representations played an integral role in the construction of croatian national identity and the mobilization of croatians around a variety of political agendas. the objective of this article is not, however, simply to document the deployment of balkanist stereotypes against or within croatia. the second component of the article suggests ways in which croatia’s liminal position between “europe” and the “bal- kans” might serve as an ideal standpoint from which one might challenge the binary oppositions of balkanism and begin to reimagine the balkans, redirecting these categories as a site of political engagement and critique. keywords: croatia; franjo tu¦man; balkanism; balkan introduction when croatia seceded from the socialist federal republic of yugoslavia in , croatians were optimistic that their new- found independence would accomplish two things: croatia would be recognized as a sovereign state for the first time in its east european politics and societies, vol. , no. , pages – . issn - © by the american council of learned societies. all rights reserved. doi: . / * for comments and criticisms of earlier versions of this article, we would like to thank kristina balalovska, pamela ballinger, dušan bjelic !, boris buden, ana devic !, gergana dimitrova, eric gordy, renata jambrešic !-kirin, dejan krsic !, maria todorova, and two anon- ymous reviewers. previous versions were presented at the kokkalis graduate student work- shop at harvard university in february and the brown university watson institute’s “whose self-determination?” workshop in february . maple razsa acknowledges the support of a fulbright scholarship from the institute of international education, and nicole lindstrom acknowledges funding from the institute for the study of world politics. national history and would “return” to its rightful place in europe. croatia’s prospects were encouraging. during the cold war, yugoslavs’ relative economic prosperity and freedom to work and travel abroad made yugoslavia the envy of eastern europe. jeffrey sachs selected yugoslavia in as one of the first coun- tries to undergo “shock therapy.” its advanced economic liberal- ization and strong civil society tradition promised a quick and successful transition to a democratic free-market state. of the six republics that made up the yugoslav federation, croatia was, like slovenia, more integrated in to european networks than other republics due to its hapsburg legacy, geographical location, and trade orientation toward western markets. in less than ten years, croatia’s status shifted from first in line to join the european union to one of the last. croatia now lags behind the economically less advanced states of romania and bulgaria in european union accession negotiations. croatia’s unfavorable position in the eyes of the west undoubtedly stemmed in part from franjo tu¦man’s dismal democratic and human rights record in the s. the tu¦man regime sup- pressed critical media outlets, supported croatian secessionists in bosnia-herzegovina, and fought the extradition of indicted war criminals to the international criminal tribunal for the for- mer yugoslavia (icty). the council of europe cited these rea- sons for postponing croatia’s membership until . the euro- pean union raised the same factors in blocking croatia’s request to start membership talks in . refugee return, full coopera- tion with the icty, and commitment to regional cooperation are conditions of croatia signing a stabilization and association agreement with the european union (a special process created for “western balkan” states in ). east european politics and societies . susan woodward, balkan tragedy (washington, dc: brookings institution press, ), . . croatia’s gdp per capita, in $u.s. at ppp, in was , ( percent of the eu average), compared to , in romania ( percent of eu average) and , in bulgaria ( percent of eu average). romania and bulgaria signed accession partnerships with the european union. world bank development indicators to , cited in blue bird agenda for civil society in southeast europe, in search of responsive government: state building and eco- nomic growth in the balkans (budapest, hungary: center for policy studies, central euro- pean university, ), . . croatia signed a stabilization and association agreement with the european union in octo- ber . the european union’s relations with south east europe is outlined at http:// europa.eu.int/comm/external_relations/see/. the enormous fall in croatia’s international standing did not depend solely on western perceptions of tu¦man’s political fail- ings or its economic performance. croatia’s fall from grace also involved the deployment of balkan stereotypes by western lead- ers and journalists—a phenomenon maria todorova terms “balkanism.” in other words, balkanism proved a very effective method of disciplining states like croatia with strong european aspirations. the irony, however, is that croatians deployed simi- lar balkan stereotypes to differentiate themselves from their eth- nic neighbors. balkanist rhetoric was utilized to legitimize croatia’s quest for independence as a necessary emancipation from its “balkan burden” and its return to its rightful place in europe. croatians presented themselves as more progressive, prosperous, hard working, tolerant, democratic, or, in a word, european, in contrast to their primitive, lazy, intolerant, or bal- kan, neighbors to the southeast. this article examines the discursive processes through which croatian leaders framed their so-called exit from the balkans and return to europe throughout the s. the first section provides a brief review of the work of todorova and others who critically examine the external and internal symbolic representations of the balkans. the second part traces croatia’s fall from grace, from the euphoric declarations of returning to europe in the early s to lamentations by the late s of being relegated to the status of a small, marginal, autocratic state. the third part examines three discursive strategies by which croatian leaders define their respective visions of croatian national identity based on quite different conceptions of what they see as essential euro- pean norms and values. we show that the europe-balkan dichot- omy is an important element of national self-understanding in all three cases; yet europe always stands outside the nation, as an identity to be achieved. the concluding section considers how balkan is beautiful . maria todorova, imagining the balkans (london: oxford university press, ), . . milica bakic !-hayden and robert hayden, “orientalist variations on the theme ‘balkans’: symbolic geography in recent yugoslav cultural politics,” slavic review (spring ): - . . see susan gal, “bartók’s funeral: representations of europe in hungarian political rhetoric,” american ethnologist : ( ): - . gal suggests the rhetorical slogan “return to europe” implies such a duality, for one must return to a place where one currently does not belong. negative representations of the balkans might be critically exam- ined to reimagine the balkans as a site of positive engagement and critique. imagining the balkans the burgeoning literature on balkanism provides a useful framework in which to examine the forms and processes of rep- resentation through which croatian leaders negotiated their so- called final exit from the balkans and return to europe. maria todorova and other scholars seek to critically examine how a geographically and historically defined place—the balkan penin- sula—has become a symbol imbued with a host of derogatory meaning. to varying extents, these scholars are all indebted to edward said’s orientalism, a seminal critique of western knowl- edge and representations of the east. they hold differing opin- ions, however, over the extent to which balkanism can be inter- preted within a general orientalist or postcolonial frame. in imagining the balkans, todorova traces the genealogy of balkanism through the travel writings of western authors to explore how the term “balkan” has been negatively constructed over the past three centuries. todorova divides the evolution of balkanism into three stages: . the balkans were first “discovered” in the late eighteenth century by western travelers. although these first western accounts of the balkans contained some geographical inaccuracies, their treat- ment of the balkans was primarily classificatory and descriptive. . after a series of balkan wars and with the advent of world war i, the balkans were increasingly imbued with “political, social, cul- tural, and ideological overtones,” and “balkan” was increasingly used as a pejorative term. . today the term “balkan” has been almost completely disassoci- ated from its object, as journalists and academics utilize the con- east european politics and societies . other works in this tradition include dušan bjelic ! and obrad savic !, balkan as metaphor (cambridge, ma: mit press, ); k. e. fleming, “orientalism, the balkans, and balkan historiography,” american historical review : ( ): - ; patrick hyder patterson, “on the edge of reason: the boundaries of balkanism in slovenian, austrian, and italian discourse,” slavic review : (spring ): - ; vesna goldsworthy, inventing ruritania: the imperialism of the imagination (new haven, ct: yale university press, ). struct of the balkans as a powerful symbol conveniently located outside any spatial or temporal contexts. “balkanization” has now come to signify more generally the dis- integration of viable nation-states and the reversion to “the tribal, the backward, the primitive, the barbarian.” these balkan ste- reotypes were reinvigorated by the recent wars in the former yugoslavia, which were often termed balkan wars despite the fact they were confined to former yugoslav republics. todorova’s archaeological approach to the study of the bal- kans and balkanism shares much with edward said’s analyses of orientalism. said explores how european culture managed and produced the east “politically, sociologically, ideologically, sci- entifically and imaginatively” through discourses on the orient, or what he has termed “orientalism.” by construing the “orient” as the essentialized “other,” through a dichotomous and essentialist system of representations embodied in stereotypes, western writers have strengthened the west’s own self-image as the superior civilization. todorova shows how a similar phenom- enon exists between the balkans and europe. she writes, geographically inextricable from europe, yet culturally constructed as “the other,” the balkans became, in time, the object of a number of externalized political, ideological and cultural frustrations and have served as a repository of negative characteristics against which a posi- tive and self-congratulatory image of the “european” and “the west” has been constructed. while orientalism is a “discourse about an imputed opposition,” todorova argues that balkanism is a “discourse about an imputed ambiguity.” here todorova differs from other balkan theorists in the orientalist tradition such as bakic !-hayden and hayden, who argue that balkanism can indeed be viewed as a “variation on the orientalist theme,” since the balkans were long under balkan is beautiful . maria todorova, imagining the balkans, . . maria todorova, “the balkans: from discovery to invention,” slavic review (summer ): . . edward said, orientalism (new york: vintage books, ), . . todorova, “the balkans: from discovery to invention,” . . todorova, imagining the balkans, . ottoman rule and, hence, have since been considered part of the “orient.” todorova argues that the balkans are a part of europe, albeit a provincial or peripheral part for the last several centuries. balkanism, according to todorova, treats the differences within one type—“europe”—rather than the difference between imputed types (i.e., the “occident” and the “orient”). the bal- kans, in other words, despite its geographical status as european, has become europe’s shadow, the structurally despised alter ego, the dark side within. from europe to the balkans: croatia’s “fall from grace” in the s balkanism has been a common discursive tool deployed by the west to explain and justify croatia’s enormous fall in interna- tional standing. when croatia and slovenia declared independ- ence in june , a consensus existed among the international community that yugoslavia should be preserved to guarantee stability. by the end of the year, with nearly one-third of croatian territory under serbian control and medieval dubrovnik under siege, western leaders and media now portrayed croatia as an emerging european democracy to be defended against slobodan miloševic !’s expansionist aims. germany took the lead in recog- nizing croatia in december . by april , the international community recognized croatia as a sovereign state. croatia’s image as a victim of serb aggression was soon tar- nished by its involvement in the to war in bosnia- herzegovina. tu¦man and the croatian armed forces supported the bosnian croats against the bosnian serbs, then against the bosniak muslims. television footage of the croatian armed forces’ shelling of the muslim quarters of the bosnian town of mostar, and the collapse of the historic bridge across the neretva, soon supplanted footage of serbian shelling of croatian targets. croatia now assumed a more ambivalent role in western media east european politics and societies . bakic !-hayden and hayden, “orientalist variations,” . milica bakic !-hayden, “nesting ori- entalisms: the case of the former yugoslavia,” slavic review (winter ): . . todorova, imagining the balkans, ; todorova, “the balkans: from discovery to inven- tion,” . accounts as both an aggressor and victim. in the summer of , the croatian army retook most of croatia’s occupied territory, forcing thousands of croatian serbs to flee to bosnia and serbia. soon after, tu¦man signed the dayton peace accords ending the war in bosnia-herzegovina. tu¦man’s long-term aspirations to return croatia to europe were thwarted when the european union decided in not to invite croatia to start membership talks, criticizing the tu¦man regime’s authoritarian tendencies. by the late s, many western leaders viewed croatia as another autocratic and expansionist balkan regime. an episode during a conference in zagreb, “post-dayton croatia,” typifies how balkanism became an effective means of disciplining states like croatia that aspire to be recognized as european. in front of an audience of luminaries including the croatian minister of defense and other prominent representatives of croatian political and academic communities, the u.s. charge d’affaires of the u.s. embassy in bosnia-herzegovina stopped in the middle of a biting critique of the contemporary croatian polit- ical situation. he remarked, pointedly and with obvious calcula- tion, “in the balkans . . . and when i say balkans i mean here in croatia.” clearly aware of croatian pretensions to join a more prestigious civilizational camp, the u.s. official let the assembled croatian elites know that their inclusion in the european union was currently unfeasible. he also reminded them that western leaders ultimately decided who was european and who would be kept out of the club. western policy makers are not the only ones to use balkanism as a discursive tool to reprimand croatia in the s. balkanism has also played an important role in the construction of croatian national identity during the period. in the period prior to and subsequent to the outbreak of war in july , croatian leaders aimed to promote an identity that would be maximally differenti- ated from its yugoslav identity and other constituent nationalities that made up the former yugoslavia, most significantly, serbia. serbia and croatia have historically been closely linked: more than percent of croatia’s population is ethnically serb, the ser- bian and croatian languages are linguistically very similar, and croats and serbs are both considered “ethnically” slav. serbia balkan is beautiful also posed a genuine military threat to croatia’s independence and territorial integrity. thus, this process of differentiation was quite acute, and balkanist discourse filled an important ideological role. a political cartoon published in the croatian daily slobodna dalmacija early in illustrates how balkanism was deployed soon after croatia’s independence. figure highlights the sense of optimism shared by most croatians, who believed that inde- pendent croatia would soon “sail” into europe, leaving their primitive balkan neighbors and communist past behind. serbs are represented as primitive cavemen, huddled under their nationalist insignia with their yugoslav national army helmet beside them. the croatian figure is donned in an overcoat, wav- ing farewell with a kerchief of the croatian “šahovnica” (a cro- east european politics and societies figure : at the beginning of the conflict with serbia, many croatians were optimistic they would sail into europe source: croatian ministry of information, . atian national symbol) in hand. a sail made of the european union flag powers the continental drift. by , croatia’s quest to rejoin europe proved to be more difficult than originally anticipated. figure suggests how cro- atians feared being symbolically placed into an entirely different geographical sphere. footage from the civil war in yugoslavia shown on western television screens now associated croatia not with the states of europe but with the violence of the wars in viet- nam and southeast asia. croatia’s exasperation of the change in fortune is captured in a front cover of the croatian political weekly magazine, tjednik (figure ) where croatia is depicted as the fair-haired girl whom no one in the world will ask to dance. the headline poses the question, “zašto nas ne vole?” (why don’t the great powers love us?). balkan is beautiful . alojz s #es #ik, ed., warikatura croatica (zagreb, croatia: hrvatska tiskara, ), . figure : croatia’s position in global symbolic geography proved to be quite changeable source: croatian ministry of information, . figure captures some of the bewilderment croatians felt at the change in their fortune. croatia’s reputation shifted from being a promising emerging democracy that european and u.s. leaders pledged to support and protect in the early s to an international pariah by . despite attempts to displace or externalize charges of balkanism, the croatian case is indicative of todorova’s claim that the “outside perception of the balkans has been internalized in the region itself.” the main way in which balkanism has been internalized in croatia is through internal differentiation based on imputed balkan characteristics; what bakic !-hayden describes as “nesting orientalisms.” an endless chain of differentiation can occur between nations, whereby croatia is balkan vis-à-vis ger- many, serbia is balkan vis-à-vis croatia, kosovo is balkan vis-à- vis serbia, and so on. orientalism can also be nested within nations. one can perceive a social hierarchy in croatia that cor- responds to the notion of where the balkan begins and europe ends. the sava river serves as one common dividing line, where the less prosperous, socialist-era, southern suburbs of zagreb are considered balkan vis-à-vis zagreb’s old “european” center. the former military frontier (or the “krajina”) also creates an internal barrier between northern croatia and its southern bal- kan border region. when herzegovinian croatians became an increasing liability to the croatian government in the late s— politically by obstructing the implementation of the dayton agreement and economically by siphoning croatian state east european politics and societies . todorova, imagining the balkans, . . bridget bereton argues that in a poly-ethnic hierarchy, the less powerful group undercommunicates its distinctiveness in relation to the more powerful group, while the more powerful group tends to overcommunicate its difference. one could argue a similar dynamic has occurred in southeastern europe, where croatians undercommunicate their difference vis-à-vis more powerful europe but overcommunicate their differences vis-à-vis the less powerful serbian (or bosnian muslims or roma). bridget bereton, race relations in colonial trinidad, - (cambridge: cambridge university press, ), . . the cover of a croatian tourist brochure declares zagreb “the new european metropolis.” . the croatian weekly feral tribune declared, for example, that herzegovinian croats were the “new serbs.” toni gabric !, “hercegovci su na?i novi srbi” [herzegovinians are our new serbs], feral tribune, august . the nationalist hrvatski obzor acknowledged that the west now identified croatia with its less developed counterparts in bosnia. its cover, with white socks hanging from a clothesline (white socks symbolizing gauche, and decidedly non-european, fashion), declared, “svi smo mi hercegovci” [we are all herzegovinians now]. hrvatski obzor, september . funds—many croatians began to draw the border of the balkans between bosnian croatians and citizens of croatia proper. in sum, critical conflicts in croatia throughout the s were shaped by the “politics of recognition” whereby croatians sought, and ultimately failed, to be recognized by western lead- balkan is beautiful figure : a croatian liberal weekly, tjednik, asks incred- ulously, “why don’t they love us?” ers as authentically european. balkanist discourse provided one means of dissociating croatia from its balkan neighbors and thus reclaiming its perceived rightful place in europe. croatia’s dra- matic “fall from grace” throughout the s can help explain croatians’ often overanxious, even paranoid, response to being identified as balkan. boris buden suggests that balkanist dis- course in croatia might indeed be an “expression of the deepest frustration caused by the fact that croatia is never really recog- nized in the vision of its own european identity precisely in the only place in which that recognition matters—in europe itself.” while tu¦man used balkanist dichotomies adeptly to secure croatia’s independence and rally western support in the early s, by the mid- s this consensus had unraveled. vesna pusic! stated in that the critical issue facing croatia was determining “who will prevail in defining the character of croatia, who will determine its identity and on which values, political attitudes, models and strategies its image will be con- structed.” in the following section, we examine how public debates over the meaning of croatian identity and croatia’s polit- ical and social future were fought within the confines of the bal- kan-europe dichotomy. although many prominent croatians sought to identify croatia as europe in contrast to the balkans, they imbued both these terms with different meanings in further- ing very different political agendas. balkanism and its critics: three discursive strategies “tu¦man, not the balkans” was the slogan on which croatian president franjo tu¦man based his successful presidential campaign. the slogan captured what tu¦man saw as his greatest historical achievement: croatia’s extrication from what one writer termed “the balkan darkness of the so-called yugoslavia.” in the post-dayton era, the general euphoria following croatian inde- east european politics and societies . boris buden, “ne, ne volim hrvatsku!” [no, i don’t love croatia!], arkzin, june . . bastard intellectual cooperative, “na grobu z #iva predsjednika,” http://www.arkzin.com/ / pusic.html. . zvonko makovic !, feral tribune, january . pendence was waning and croatians faced high unemployment and inflation. tu¦man could no longer rely solely on military or diplomatic achievements to maintain his political power. tu¦man found the perfect solution to this dilemma in the south- east european cooperation initiative (seci). the united states and the european union initiated seci to promote economic exchange within southeastern europe (including all the former yugoslavia states, albania, hungary, romania, and bulgaria). the slogan “tu¦man, not the balkans” perfectly articulated his stand on this new crisis. seci was not intended to create a “new- yugoslavia”; nor did it legally bind croatia to the agreement. nevertheless, it was nearly impossible to turn on a television or radio or to open a newspaper in croatia in without learning of the danger of a world conspiracy to force croatia “back onto the balkans.” tu¦man, once again, would save croatia from this fate. a cover of the croatian state-run news weekly hrvatski obzor illustrates how seci was represented by the ruling regime. the cover, shown in figure , is dominated by a close-up of a yugo with a headline that asks, “hoc!emo li ponovo voziti ‘yugo’ ” [will we drive yugos again?]. the yugo was a symbol of what croatians viewed as their disadvantaged status vis-à-vis the serbs in yugoslav economic relations (not to mention a source of international embarrassment), since the yugo was manufactured in serbia but was aggressively marketed among all other repub- lics as yugoslavia’s national automobile. the headline, therefore, by citing renewed economic ties through seci, reinvigorated the threat that once again croatia would fall victim to serbian hege- monic aspirations. in the upper right hand corner, however, the same cover provided the answer to this threat. beside a picture of tu¦man, the caption declared that, “croatia still needs tu¦man.” balkan is beautiful . both the eu and the united states insisted that membership in the southeast european cooperation initiative (seci) would be voluntary. ivo banac, professor of history at yale university and frequent commentator on croatian politics, stated in an interview for a cro- atian weekly, “i really don’t see anyone in the west who would force the renewal of yugo- slavia or the creation of some sort of balkan confederation. that is completely unrealistic.” feral tribune, january . during his televised state of the union address in january , tu¦man made his stand on seci official by passing a con- stitutional amendment banning croatia’s participation in balkan associations. he proclaimed, east european politics and societies figure : the conservative weekly hrvatski obzor proclaimed in , “croatia still needs tu¦man” by its geopolitical position, by all of its fourteen-century history, by its civilization and culture, croatia belongs to the central european and mediterranean circles of europe. our political links with the balkans between and were just a short episode in croatian history and we are determined not to repeat that episode again. underlying his political opposition to western attempts to force croatia into some new balkan union, therefore, was the outrage that croatia could be misrecognized as culturally balkan. by fostering a sense of crisis, tu¦man could demonstrate he was a strong and vital leader. tu¦man not only would protect croatia from the serbian threat; he would stand up to the “great powers” who now threatened croatia’s national interests. tu¦man was not the only politician to utilize balkanism as a rhetorical strategy. in his presidential campaign, croatian social liberal party candidate vlado gotovac criticized the “bal- kan tendencies” of tu¦man and, in contrast, portrayed himself as a european leader. as part of his campaign strategy, gotovac capitalized on the fact that croatia was not invited to the balkan is beautiful . “address of the president of the republic of croatia franjo tu¦man on the state of the nation at the joint session of both chambers of the croatian national parliament,” janu- ary , www.urpr.hr. tu¦man reiterated his opposition to the agreement again in his address: “it should be noted that certain, influential european and american circles insist on a program of regional balkan integration. that would actually mean the revival of the former yugoslavia without slovenia and with albania, and that goal should be opposed at all costs and by using all available means.” “address of the president of the republic of croatia dr. franjo tu¦man on the state of the nation at the joint session of both chambers of the croatian national parliament,” january , www.urpr.hr/ad .htm. on march , the croatian national parliament passed a declaration objecting to the euro- pean union’s “regional approach” and rejecting “all attempts for croatia to be included in some sort of regional integration of south-eastern europe and the balkans.” croatian for- eign press bureau’s daily bulletin / , march . . the west’s gravest mistake, according to a column in vjesnik, the largest state-run daily newspaper, is its failure to recognize that croatians have a “deep consciousness of their belonging to western civilization” and a commitment to modernization in contrast to serbia with “its links to fanatical nationalism, its support for preserving the old socialist system, and its inability to enter the information revolution.” marinko bobanovic!, “duboka je svijest o pripadnosti zapadu” [consciousness of western belonging runs deep], vjesnik, june . . dalibor foretic !, in the independent daily novi list, captures this dynamic: “the world would like to push us into some kind of balkan hole but we will not allow them. we want to be everything—central european, mediterranean, transcarpathian—and not just a balkan country. the west is constantly inventing some kind of initiative to push us where we do not belong. but we will not let them! our leaders persistently and bravely shout that croatia will not enter some new balkan integration,” october , quoted in dunja rihtman- auguštin, “zašto i otkad se grozimo balkana?” [why, and since when, are we so afraid of the balkans?], erasmus : ( , ). meeting of the presidents of central european states, the region to which tu¦man repeatedly declared that croatia belonged. in an article titled “croatia excluded from the central european milieu,” gotovac wrote, the absence of the croatian chief of state from that kind of a gather- ing not only sends a message that croatia does not belong to the cen- tral european geopolitical space. it is also clear proof that dr. franjo tu¦man himself, as the key protagonist of balkan, anti-european pol- itics, does not have access to the company of eight central european leaders. this is a clear warning that our republic with tu¦man and his nomenclature has mired us in deep isolation, leaving us hope- lessly anchored to the balkan. tu¦man’s authoritarian regime, in other words, with its violations of human rights and its increasing isolationist policies, not the west, was to be blamed for anchoring croatia to the balkan. critics of both the ruling regime and the liberal opposition also utilized balkanist rhetoric. boris buden’s vociferous and radical critiques of tu¦man demonstrated a certain ambivalence regard- ing croatia’s relationship to the balkans. in response to tu¦man’s proposed constitutional ban on associations with balkan states, for example, buden wrote with alarm, “one of the most impor- tant elements in croatian nationalist ideology—the dichotomous construct of ‘europe-balkan’—will now be given a place in the basic document of the croatian state, its constitution!” in an essay two weeks later on the popular demonstrations against miloševic ! in belgrade, buden put the binary opposition to an ideological use of his own. buden praised serbian citizens for finally rising up against miloševic !, writing that, in doing so, they had become a symbol of “europe.” juxtaposing the democratic demonstrations in serbia with the complacency of croatians east european politics and societies . novi list, june . . buden, “mission impossible,” . palanka is a term coined by the serbian philosopher radomir konstantinovic !, which is related to the english term “provincialism” but carries only its negative connotations of prejudice, close-mindedness, and cultural isolation. towards the tu¦man regime, buden argues that zagreb, not bel- grade, is the true “balkan palanka.” neither tu¦man nor gotovac would call zagreb balkan, let alone using the terminology of serbian philosopher. however, buden is reluctant to categorically define zagreb as more “primi- tive” than belgrade, conceding that there is a “possible objection that not everyone in zagreb is a primitive balkanite and that there are absolutely and relatively far more of that kind in belgrade.” although his intention is to incite protest, to spark more dramatic resistance to the tu¦man regime, buden shares the underlying balkanist orientation that “balkan” is associated with all that is dark and, conversely, “europe” with all that is light. we draw several conclusions from these three cases. first, these examples illustrate how balkanism pervaded croatian political discourse throughout the s. tu¦man, gotovac, and buden all utilize a balkanist framework in their political rhetoric, despite their significantly different ideological standpoints and political objectives. as verdery argues, “to the extent that debate promotes unspoken agreement—however circumscribed—on certain fundamental premises, then one can speak of this as a ‘le- gitimating outcome’ or ‘legitimating moment.’ ” the unspoken agreement or “legitimating outcome” of croatian political dis- course in the s, in other words, was defining croatian iden- tity as european in opposition to the balkans. this fundamental construction was also evident in academic analyses of the phe- nomena. for example, when an interviewer asked ivan siber, professor of political science at zagreb university, “how do you comment on the slogan of the hdz ‘tu¦man, and not the bal- kan?’ ” siber responded, “ ‘tu¦man, and not the balkans is a dis- tinctly balkan slogan. . . . the kontrapunkt to the balkans is europe not tu¦man.” the point here is not to simply expose the balkan is beautiful . referring to the recent display of serbian civil disobedience, buden writes that “until such demonstrations and things like it happen in our city, zagreb will not be symbol of freedom, democracy, western culture and european civil identity, but will remain a small, shitty, beat-up, balkan ‘palanka’.” “a tko to zagreb s #ini palankom?” arkzin, january . . buden, “a tko to zagreb s #ini palankom?” . . katherine verdery, national ideology under socialism: identity and cultural politics in ceausescu’s romania. (berkeley: university of califor nia press, ), . . martina staz #nik, “kontrapunkt balkanu je europa, a ne tu¦man” [the alternative to the bal- kans is europe, not tu¦man], studentski list, february . use of balkanist rhetoric in public discourse but to show how balkanism was a key discursive means of articulating croatian national identity in the s. a second insight from these examples of balkanism lies in the tension between the insistence of concretizing croatia’s place in “europe” and awareness that its status as european is ontologi- cally insecure. for instance, tu¦man repeatedly insisted that croatia’s fourteen-century old european cultural heritage ensured that croatia would quickly return to its rightful place in europe. at the same time, however, tu¦man pursued an aggres- sive lobbying campaign at home and abroad to promote croatia’s europeaness and to resist being identified as balkan by european leaders. similarly, gotovac frequently asserted croatia’s central european identity, yet noted croatia’s absence from meetings of central european states. buden claimed that while belgrade is symbolically more european, there are numerically more primi- tive balkanites in belgrade than in zagreb. all three figures, in other words, insist that croatia belongs to europe in a secure ontological sense, yet none can ignore croatia’s fall from grace throughout the s. each knows that those on the periphery of europe are particularly vulnerable to the vagaries of the changing social and political map of europe. they are aware, like todorova asserts, that “ ‘europe’ ends where politicians want it to end.” finally, while all three of these political actors share the same discursive balkanist frame of europe/balkan, each imbues these categories with different meaning. the positive attributes that tu¦man, gotovac, and buden attribute to “europe” vary. tu¦man clearly focused on the cultural cachet of europe as well as the political and military security that comes with european membership. gotovac mobilized his opposition to tu¦man around a liberal conception of europe that entailed a respect of the parliamentary rule of law, democratic norms, and the sanctity of rights. buden evoked the european tradition of antiauthoritarianism and political protest to inspire resistance against the tu¦man regime. each construction of europe east european politics and societies . todorova, imagining the balkans, . reflected each man’s respective vision of croatia’s future. all three political agendas were imagined within the confines of balkanism. in the following section, we suggest how this balkanism framework might be challenged or “reimagined” as a site of political engagement and critique. concluding remarks: reimagining the balkans as we have shown above, balkanism—a dichotomous and essentialist system of representations embodied in stereotypes around which europe has set itself apart from a balkan “other”— has served a discursive means by which croats would liberate themselves from their perceived balkan burden and return to europe. when croatia found itself in the position of being both a recipient and purveyor of balkanist stereotypes, it spurred a number of different responses. it stimulated anti-western back- lash, intensified efforts to distinguish croatia more aggressively from its balkan neighbors, and resulted, in some cases, in an internalization of these stereotypes, either through a kind of self- hatred or through the promotion of an internal hierarchy based on balkanist criteria. this change in fortune provoked little criti- cal inquiry in croatia as to why the discourse of balkanism devel- oped and continues to have such salience in europe and its periphery. most criticism directed toward the west stemmed from resentment at not being recognized as european—or for being misrecognized as balkan. todorova and others in the balkanist tradition have taken up this task. many analysts attribute the extreme nationalism and ethnic violence that followed the breakup of yugoslavia to pri- mordial hatreds and a proclivity toward violence unique to the balkans (and, subsequently, antithetical to the western enlight- enment tradition). todorova suggests that the yugoslav con- flicts in the s, wrongly attributed to some balkan essence, balkan is beautiful . notable examples include robert kaplan, balkan ghosts (new york: vintage books, ); george kennan, “introduction: the balkan crises: and ,” in the other balkan wars: a carnegie endowment inquiry in retrospect with a new introduction and reflections on the present conflict by george f. kennan (new york: carnegie endowment for international peace, ). actually marked the ultimate europeanization of the balkans. similarly, slavoj z #iz #ek suggests that what europe may be afraid to recognize in the recent yugoslav war is the violent origin of its own system of nation-states. the modern european system of sovereign states, z #iz #ek reminds us, is “the result of several centu- ries of social engineering—ethnic and religious war and expul- sions accompanying the process of centralization—triggered by a fundamental hostility to heterogeneity. which in the end brought about relatively homogeneous politics produced by the development of modern nation-states.” when yugoslavia disintegrated, what some might term its “ottoman legacy”—characterized by multinational statehood, decentralization, and regional diversity—was finally reorganized into the nationalist rubric of a centralized state system and a sin- gle unified national culture. since croatia was recognized in as an independent state, croatia has been engaged in such a nationalizing project. tu¦man placed the dalmatian and istrian regions under zagreb control. his regime also promoted a single unified culture through institutions such as matica hrvatska that work to “preserve” the purity of croatian language and culture. in general, official croatia has systematically worked toward the production of an exclusively croatian nationhood and its histori- cal imaginary into the institutional tissue of its state, a project that most european states have long since “achieved.” this issue cer- tainly warrants further study, not simply to better understand the particularities of croatian nationalism; one can consider how the project of radical nation building is embedded in the very project of modernization and europeanization. what are some of the political consequences of entangling this nation-building process with balkanism and within a cultural hierarchy that privileges all that is “european” over all that is “bal- east european politics and societies . todorova, imagining the balkans, . . slavoj z #iz #ek, the metastases of enjoyment (london: verso, ), . . examples of research on this relationship include petr drulák, ed., national and european identities in eu enlargement: views from central and eastern europe (prague, czech republic: institute of international relations, ); lene hansen, “slovenian identity: state building on the balkan border,” alternatives : ( ): - ; merje kuus, “european integration in identity narratives in estonia: a quest for security,” journal of peace research ( ): - ; mikko lagerspetz, “postsocialism as a return: notes on a dis- cursive strategy,” east european politics and societies ( ): - . kan”? for one, any organization of croatian identity along dichot- omous balkan/european lines masks croatian ethnic preoccupa- tions with the serbs. among many croats, serbs are seen as the epitome of a balkan people. defining “croatianess” in opposi- tion to “balkaness” fosters animosity toward croatia’s largest minority and important neighbor. moreover, by deploying balkanism against those to its south and east, croatians accept a social hierarchy based on cultural characteristics that, as we have shown, has hindered croatia’s own european membership aspi- rations. in other words, although croatia might define itself as more european vis-à-vis serbia according to cultural and geo- graphic criteria, it is ultimately the european union that deter- mines croatia’s geopolitical status. this strategy of differentiation appears increasingly problematic given that croatia is destined to remain with serbia in the european union’s “western balkans” group of applicant states for the foreseeable future. croatia’s perceived failure to be recognized as european does not necessarily have to result in an externalization or internaliza- tion of cultural hierarchies. we share z #iz #ek’s cautious optimism that by being forced to live out and sustain the competing and often contradictory demands of the national and transnational, the inside/outside, central and east europeans are located in a privileged position to invent creative ways out of this dilemma. croatia has an ideal vantage point from which to articulate such a narrative, for croatia has long been placed on both sides of important historical and geographical divides: classified as both byzantine and catholic, ottoman and austro-hungarian, eastern and western, balkan and european. at times, croatians have embraced this in-between position, causing croatian nationalist eugen kvaternik to proclaim in , for example, “croats are the most magnificent nation in europe. they took possession of this blessed country and forever developed a true way of com- municating between the christians of the east and the christians of the west. show me a feat such as that in any other contempo- rary nation!” more typically, croatians have either enthusiasti- balkan is beautiful . slavoj z #iz #ek, the spectre is still roaming (zagreb, croatia: arkzin, ) . eugen kvaternik, istocno pitanje i hrvati, (zagreb, croatia: dom i svijet, [ ]), . cally or grudgingly accepted their role as the “defense walls of christianity” (antemurale christianitatis), tasked to defend west- ern culture against the east. for the most part, they have consid- ered this border identity as an obstacle to achieving their own autonomous nation-state and privileged place in europe. cro- atians might turn to the experiences of other peripheral euro- pean states to begin to explore the “radical ambivalence” of being situated in this middle ground. todorova suggests that it may be hardly realistic to expect nation-states designated as balkan to create a “liberal, tolerant, all-embracing identity celebrating ambiguity and a negation of essentialism” in the face of “persistent hegemonic discourse from the west, continuously disparaging about the balkans, which sends out messages about the politicization of essentialized cul- tural differences.” what is genrally true of nation-states in gen- eral is perhaps more true of croatia given the trauma of its recent past. much of contemporary cultural studies focus on the poten- tial for cultural resistance in the appropriation and redeployment of dominant discourses or the search for organic counterhege- monic articulations. the notion that individuals—or, by exten- sion, nations—can shape their own processes of signification fails to examine the degree to which this process is bound by larger historical and structural factors. it is important to consider sherry ortner’s reminder that “culture controls the definitions of the world for actors, limits their conceptual tools, and restricts their emotional repertoires.” acknowledging these constraints, it is always possible for those objectified by categories to reappropriate them, make them one’s own, give them new meaning, and thereby redirect them as forms of political engage- east european politics and societies . ëur¦a knez #evic !, the enemy side of national ideologies: croatia at the end of the th cen- tury and in the first half of the th century, history department working paper series ii (budapest, hungary: central european university, ), . . stephen slemon, “unsettling the empire: resistance theory for the second world,” world literature written in english ( ): . . todorova, imagining the balkans, . . sherry ortner, “theory in anthropology since the sixties,” comparative studies in social history : ( ): - , quoted in mattijs van de port, gypsies, wars and other instances of the wild: civilisation and its discontents in a serbian town (amsterdam: amsterdam university press, ), . ment and critique. therefore, just as many african americans worked to turn racist representations on their head, croatians might one day declare that “balkan is beautiful.” balkan is beautiful . david theo goldberg writes of race, but which could be true of the balkans, “although race has tended historically to define conditions of oppression, it could, under a culturalist interpretation—and under some conditions perhaps—be the site of a counterassault, a ground or field for launching liberatory projects or from which to expand freedom(s) and open up emancipatory spaces.” david theo goldberg, racist culture: philosophy and the politics of meaning (cambridge, ma: 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(journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ jss- - - - - -chiweshe-n-tx[ ].pmd © kamla-raj j soc sci, ( ): - ( ) youth consumer behaviour: a case of beauty product consumption shayna amaidas and nigel chiweshe university of kwazulu-natal, school of management, it and governance pietermaritzburg, private bag x , scottsville , south africa telephone: + - , e-mail: , keywords advertising. brand image. brand relationships. generation y. self-image. beauty products abstract when consumers go grocery shopping, their baskets end up filled with specific branded products. why? these products carry a brand name which is a promise to deliver on sought aspects by the consumer.the beauty product industry is one of the fastest growing industries in the world and a multibillion-dollar market on the african continent.this paper sought to offer insights to consumption influenced by brand image and self-image in the context of the african beauty product market with special attention given to south africangenerationy females. a quantitative research design was adopted in order to fulfil the objective of this investigation into brand and self-images influence on consumption behaviour of the youth. a questionnaire was used to obtain insights from females within the age group - . the key findings suggested post-exposure to adverts influences appearance satisfactions.the findings further revealed that these female consumers may doubt the claims made in adverts however, they regard these communications as being reflective of their desired self-images and hence consume these beauty products. recommendations that arose from this study were that marketers in their pursuit to profitably satisfy consumer needs would be advised to make use of realistic depictions of beauty and models in order to further guide the consumption of their branded products. address for correspondence: mr. n. chiweshe school of management, it and governance, university of kwazulu-natal, pietermartizburg campus, kwazulu-natal, , south africa telephone: - - e-mail: chiweshen@ukzn.ac.za introduction in modern popular culture, body image norms are preserved in the various forms of advertis- ing, by preferential selection of “good looks” in companion-selection, and by the association of reduced aptitude in individuals not portraying “accepted” body proportions. this issue of idealized images in advertising is so prevalent in society that young females have little chance of escaping messages that communicate these idealize dimages (wan et al. : ). further, the portrayal of beauty in beau- ty product advertising seems to be one-sided which has a direct positive influence on con- sumers’ behaviour (dittmar et al. ; grabe et al. ; yamamiya et al. ) which can in- clude personal, social, cultural and psychologi- cal factors of an individual’s life. questions relating to brand image and the advertising of beauty products in a south afri- can context of generation y females have been limited in coverage yet this is a large, growing and profitable segment which in principal repre- sents a potentially viable target. this, in an era where the beauty product market for items such as synthetic hair on the african continent has a value of seven billion dollars with countries such as south africa, nigeria and cameroon spend- ing one billion dollars (euromonitor ). therefore, deeper insightsinto the consum- er behaviour of generation y females in south africa, who on being exposed to advertising of various brands and their associated images,tend to construct various images of ‘self’ that can shape their consumption behaviour. objective the paper sought to provide insights on brand and self-images’ influence on consump- tion behaviour of the youth. theoretical concepts branding a brand is a name, term, sign, symbol, or design, or a combination of these items intend- shayna amaidas and nigel chiweshe ed to identify the goods and services of one seller or groups of sellers and to differentiate them from those of competitors (keller : ). in other words, a brand may be viewed as an assortment of both tangible and intangible at- tributes, represented in a trademark, which may generate influence and value (kotler and arm- strong : ). in the absence of brands, con- sumers would be unable to differentiate one product from another (ponsonby-mccabe and boyle : ). brand image several definitions exist regarding the term ‘brand image’, the most common one being that a brand image may be defined as, “the set of beliefs, ideas, and impression that a person holds regarding an object” (kotler : ). similar- ly, aaker ( : ), zhang ( : ) and biel ( : ), considered brand image to be, “a clus- ter of attributes and associations, usually orga- nized in some meaningful way”. keller ( : ) instead deliberated brand image as, “a set of perceptions about a brand as reflected by brand associations in a consumer’s memory.” brand image and beauty products meenaghan ( : ) is of the belief that, “there is no objective reality and that people trade in the realms of perception and image”. the area of marketing involves the relationship between consumers and business and therefore brand images have formed an important aspect in current times. a variety of reasons for this increased emphasis on brand image in market- ing can be suggested (king : ; parker : ; chung et al. : ): marketing’s increasing cognizance of the behavioural aspects of consumer decision- making; affluent society’s predilection with sym- bolic rather than purely functional aspects of products; an increasing variety of relatively homo- geneous products often involving high product complexity and confusing messag- es which increase consumer reliance on the image aspects of products; the fact that technological innovation, in- creasingly susceptible to rapid imitation, may no longer offer previous levels of sus- tainable competitive advantage. in the beauty product industry, appearance is everything and hence, similarity between a brand’s image and a consumer’s self-image (self- concept) can have significant effects on con- sumers’ brand evaluations and purchase inten- tions (wan et al. : ). promotional messages that encourage con- sumers to think about their own self-image while evaluating a brand magnify the effects of brand images this is further supported by festinger’s social comparison theory which states that indi- viduals evaluate themselves whenever they ex- perience some form of comparison (wan et al. : ). . generation y females generation y according to velentine and powers ( : ) is a unique and influential consumer segment where there has been limited understating of their consumer behaviours. gen- eration y, also known as the echo boomers or millenials (belch and belch : ), are the children of the baby boomers generation and were born after . generation y females trea- sure individuality though they still want to be deemed as part of the group (yarrow and o’donnell : ). consumers between the ages of and are the demographic most con- cerned about image and lifestyle trends and in- fluenced by, “what’s hot and what’s not” (gluck ). in terms of spending power, they have more money to spend than consumers of the same age groups but from previous generations (morton ; mafini et al. : ). this seg- ment of consumers is heavily influenced by tech- nology such as the internet and has significant- ly ‘evolved’ from previous generations thus pre- senting a challenge in targeting them (valentine and powers : ). self-image (self-concept) evidence supports the assertion that attrac- tive people portrayed in various marketing com- municationsaffect female consumers’ global per- ceptions of their own facial attractiveness and body (englis et al. ). this view is further supported by the findings of smirnova ( : ), which states that advertisements influ- ence how women understand their bodies. ac- cording to sharp et al. ( : ) there has been a noticeable acceleration in the demand for cos- youth consumer behaviour metic surgery driven primarily by body image concerns influenced by socio-cultural influenc- es such as media through programmes such as extreme makeover and embarrassing bodies and advertising. sharp et al. ( : ) study indicated that there was a positive correlation between inter- nalization, comparison and body dissatisfaction. catalin and andreaa ( : ) and hosany and martin ( : ) state that generally consum- ers will tend to select a brand that is congruent with their self-image. baumann et al. ( : ) and hosany and martin ( : ) further state that the image portrayed by the brand can be an extension of the self-image. brands can be regarded as a source of personal reassurance and indicate to others the kind of person they are. consumer-brand relationships and marketing communication in their exploration of the emotional signifi- cance of the relationships between consumers and brands, reimann et al. ( ) suggest that close relationships are motivated by rapid self- expansion; this being the acquisition of resourc- es, perspectives and identities that enhance one’s ability to accomplish goals. with rapid self- expansion, emotional arousal increases (aron et al. ; schmit ) and as such, brands can give consumers “ideal selves” to aspire to, since the presentation of self through possessions allow consumers to differ from what may be their “real selves” (malär et al. ). female images in marketing communication young women are frequently exposed to messages and images that reinforce the body ideal, which become the standards (wan et al. : ). they are made to feel as if their phys- ical beauty determines how they and others judge their overall value (smirnova : ; lykins et al. : ). these perceptions seem to result from a socialization process that be- gins at a very early age, continues throughout childhood, and is reinforced in adolescence (berger and luckman ; smirnova : ). a heightened awareness of other people’s perspectives, along with a need to shape their own identity and conform to group expectations, results in more attention to the social aspects of being a consumer, making choices and consump- tion (john ). research to date, reports that some children, adolescents and young women are prone to in- ternalization, high levels of body focus, a high degree of body size dissatisfaction, body image distortions, eating disorders and related self- perception and self-esteem issues partly as a result of the negative effects of thin media mod- els (halliwell and dittmar ; dittmar and howard a; dittmar and howard b; th- ompson and stice ; lykins et al. ). cattarin et al. ( ) examined the effects of media-driven images of attractiveness on the level of body image and mood disturbance amongst females. their findings suggest wom- en experience distress (in terms of anger, anxiety and depression) when viewing media images that reflect the current societal bias towards thin- ness and attractiveness. similarly, stice and shaw ( ) found exposure to ultra-thin models in advertisements and magazine pictures produced depression, stress, guilt, shame, insecurity and body dissatisfaction in female college students. according to festinger’s ( ) social com- parison theory, individuals engage in self-eval- uation whenever they encounter a comparative other. that is, information about the compara- tive other is used as a basis for assessing their self-view. the key to understanding how wom- en relate to advertising is to understand how they relate to themselves and the image they hold of their self when exposed to certain adver- tising images; whether the advertising makes them feel good or bad, which may then influ- ence their propensity to buy the product. sec- ondly, is how women see the models that are used in the adverts, and again how that makes them feel about themselves (borland and akram ). mask et al. ( ) in their study of how por- trayals of women convey another ideal that wom- en with little self-determination feel obliged to follow, revealed that adverts featuring thin fe- male athletes engaged in various activities of- fered greater body dissatisfaction than adverts bearing normal weight athletes effects of beauty product advertisements in south africa, the invasion of american and european images of beauty has severely impacted the concept of what it is. they brought shayna amaidas and nigel chiweshe images which are very different to what beauty was known to be before, and therefore our imag- es of beauty have been internationalized and this is reflected in the way that young women aim to look today. driving the public’s concep- tion of beauty by sending powerful messages about physical perfection everywhere we turn, the media is considered the most influential edu- cation medium in existence today (hoffmann ). the media’s influence, combined with peer pressure and the heightened self-consciousness of young females can create an unflattering im- age in the mirror that’s simply not what everyone else sees (webb ; webb et al. : ). the average woman sees to adver- tisements per day and by the time she is years old, she has received over , commercial messages through the media (croft ). val- entine and powers ( : ) in their study of generation y values and lifestyle segments re- vealed that females in this generational cohort respond better to the visual aspects of market- ing communication. with generation y females being predisposed to peer pressure and the de- sire to fit in, the marketing work behind the beau- ty industry is fiercely and intensely well thought out to influence consumption behaviour of beau- ty products. advances in digital technology make it pos- sible for anyone with a computer and image- manipulation software to cut, paste, enhance, airbrush or otherwise alter a wide range of imag- es. digital techniques are so popular that it is becoming difficult to distinguish between real photography and digital imaging (kershaw ). methodology for this research, the sample of the study was drawn from females studying from the age of - at a tertiary institution in the kwazulu- natal province. the data was collected through the use of self-administered questionnaires over a two-month period. non-probability sampling, in the form of purposive sampling was used.this form of sampling refers to the selection of candi- dates that are in the best position and provide the most relevant and applicable information re- quired (welman and kruger : ). two hundred females between the ages of and responded to the questionnaire. the figure of respondents was inline with sam- ple sizes related to generation y research as ex- pressed by mafini et al. ( : ) who cited sim- ilar sample sizes in research conducted by bakewell and mitchell ( ), drake-bridges and burgess ( ), durvasula et al. ( ), kim ( ), and kwan et al. ( ) (table ). results and discussion how do female youth consumers perceive beauty product brand images? from the literature presented earlier, it has been established that an image is the mental construct developed by the consumer on the basis of a few selected impressions among the flood of the total impressions. such impres- sions are gained when viewing marketing communications. table indicates the extent to which con- sumers believe the statements or claims made in beauty product advertisements. although the majority of respondents were neutral on the sub- ject, a close second, with thirty-six percent dis- agree that the statements or claims made in beau- ty product advertisements are believable. find- ings in table indicates that a significant per- centage of consumers experience doubt with re- gards to the statement or claims made in beauty product advertisements, which can (from litera- table : beliefs in the statements/claims made in the advertisement about beauty products frequency percent cumulative percent valid highly . . disagree disagree . . neutral . . agree . . highly agree . . total . table : respondent profile frequency percent cumulative percent valid white . . black . . indian . . coloured . . total . youth consumer behaviour ture) negatively affect the image of a brand. ce- bisa ( ), sharp et al. ( : ), catalin and andreaa ( : ), hosany and martin ( : ) and baumann et al. ( : ) state that when customers purchase products, they also pur- chase the benefits associated with products. though they may express doubt there is still the aspect of social comparison with the displayed image. does a female’s subsequent to being exposed to images of the ‘ideal’ beauty through advertising, are females’ self-image affected? table revealed that thirty-four point give percent of the respondents were only moderate- ly satisfied with their appearance. consumers’ satisfaction largely depends on the way they perceive themselves as well as themselves com- pared to the advertisement (wan et al. : ; sharp et al. : ; webb ; webb et al. : ) table indicated a p-value of less than . when appearance satisfaction and feelings post- exposure to a beauty product advertisement were correlated. this p-value is less than . and indicates a statistically significant correlation. the pearson correlation coefficient (r–value) of - . indicates a medium correlation between appearance satisfaction and one’s feelings post- exposure to beauty product advertisements. the way in which respondents feel after see- ing a beauty product advertisement depends negatively on respondents’ satisfaction with their appearance (wan et al. : ; smirnova : ; sharp et al. : ). the more satisfied one is with her appearance, the less inadequate she will feel after being exposed to a beauty prod- uct advertisement. from the answers to the key questions above, it can be concluded that the advertising of beauty products provides inconsistent out- comes in relation to the usage, purchase and expenditure decisions of generation y female- sand hence their consumer behaviour. this con- clusion is in line with various image-related stud- ies by henderson-king and hoffman ( ), table : correlations for a combination of factors correlations appearance importance of believability definition feelings post satisfaction appearance of claims of beauty exposure appearance pearson . . * - . - . ** satisfaction correlation sig. ( -tailed) . . . . n importance pearson . . ** . . of appearance correlation sig. ( -tailed) . . . . n believability pearson . * . ** . -. of claims correlation . * . ** . -. sig. ( -tailed) . . . . n definition pearson -. . . . * of beauty correlation sig. ( -tailed) . . . . n feelings pos pearson -. ** . -. . * t exposure correlation sig. ( -tailed) . . . . n *. correlation is significant at the . level ( -tailed).**. correlation is significant at the . level ( -tailed). table : respondents’ satisfaction with own ap- p e a r a n c e frequency percent cumulative percent valid not at all . . slightly . . moderately . . mostly . . very satisfied . . total . shayna amaidas and nigel chiweshe mills et al. ( ), myers and biocca ( ), hawkins et al. ( ), stice and shaw ( ) as cited by wan et al. ( : ). beauty product advertisements that focus on the differences between consumers’ actual and ideal self, influ- ence consumers to make decisions to fit in with the images of “ideal beauty” by purchasing and using the beauty products promoted. managerial implications advertisements for beautyproducts seem to make consumers feel that their current attrac- tiveness levels are different from what they would ideally like them to be (wan et al. : ; sharp et al. : ). in order to shape con- sumer behaviour in terms of beauty products, it is proposed marketers provide realistic models in their communication to generation y females. this will allow for trust to be gained from con- sumers, thereby increasing the brands’ image and allowing for positive perceptions. conclusion this paper presented the findings from both the literature review and the empirical survey on generation y female consumption behaviour and self-images, focusing on beauty productadver- tisements. the credence of beauty product ad- vertising is veiled by exaggeration, retouching and reconstructed perfection and as such the female images represented in the various forms of media have moved from the spotlight and glam- our into research studies. these idealized fe- male stereotypes affect young females’ self-es- teem, confidence, body image and self-identity, especially given the fact that advertising mes- sages are being received by a much younger audience these days. the paper has endorsed that the brand im- ages of beauty product brands are vital in pro- moting consumer behaviour in terms of usage, purchasing and expenditure as well as embed- ding the image of the company through truthful and unexaggerated advertising. consumers’ self- images are closely related to consumer behav- iour or perceptions in that individuals tend to buy products that could enhance their self-con- cept and they avoid those that do not. recommendations the study focused on a limited number of generation y consumers and in the future, a broader study should be conducted to offer gen- eralizability. the influence of product attributes of the beauty products was not examined in terms of the influence the communication of this has on consumer behaviour of generation y female con- sumers. a focus on particular brands could offer greater insights into the actual influence they have on self-image and ultimately consumption. structural equation modelling was used to reveal which constructs actually shape the con- sumer behaviour of generation y female con- sumers when it comes to beauty products where image is an area of concern. the desire to ex- press self-image through brands can be investi- gated to offer implications for marketers of prod- ucts consumed by generation y females. a gen- der comparative study would be of value to as- certain if there are any differences in relation to male and female self-image and consumption behaviour of beauty products. the various generational cohorts of consum- ers can be studied to offer greater insights on how marketing communication impacts on self- image and ultimately consumption behaviour of beauty products. studies on the motivational differences in moderating generation y female’s responses to media body ideals could be exam- ined to offer marketing practitioners avenues to further communicate their brands. references aaker da . managing brand equity. new york: macmillan. aron a, norman cc, aron en, mckenna c, heyman re . couples’ shared participation in novel and arousing activities and experienced relationship qual- ity. journal of personality and social psychology, ( ): - 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. welman jc, kruger sj, mitchell b . research methodology. rd edition. oxford: oxford universi- ty press. yamamiya y, cash tf, melnyk se, posavac hd, posa- vac ss .women’s exposure to thin-and-beauti- ful media images: body image effects of media-ideal internalization and impact-reduction interventions. body image, : - . yarrow k, o’donnell j . gen buy. san francisco: jossey-bass. zhang y . the impact of brand image on consum- er behaviour: a literature review. open journal of business and management, : - . the demands of beauty: editors’ introduction vol.:( ) health care analysis ( ) : – https://doi.org/ . /s - - - e d i to r i a l the demands of beauty: editors’ introduction heather widdows · fiona maccallum published online: july © the author(s) abstract this article introduces a special issue comprising four papers emerging from the beauty demands network project, and maps key issues in the beauty debate. the introduction first discusses the purpose of the network; to consider the changing demands of beauty across disciplines and beyond academia. it then summarises the findings of the network workshops, emphasising the complex place of notions of normality, and the different meanings and functions attached to ‘normal’ in the beauty context. concerns are raised here about the use of normal to justify and moti- vate engaging in beauty practices such as cosmetic surgery and ‘non-invasive’ proce- dures. other workshop findings included the recognition of beauty as increasingly a global value rather than a culturally distinct ideal, and the understanding that there is no clear distinction between beauty practices that are considered standard and those that are considered extreme. these themes, especially the concerns around under- standing of normal, are reflected in the recommendations made by the network in its briefing paper, which are presented next in this introduction. a further theme picked up by these recommendations is the extent to which individuals who are not traditionally vulnerable may be so in the beauty context. finally, the introduction highlights the key matters covered in the four papers of the special issue: regulatory concerns around cosmetic surgery tourism; the impact of digitally altered images from psychological and philosophical perspectives; the ethics of genetic selection for fair skin; and the attraction and beauty of the contemporary athletic body. keywords beauty ideals · beauty practices · normalisation · globalisation · cosmetic surgery this volume is one of the outcomes of an ahrc network grant “the changing requirements of beauty” which begin in september . the network was led by four academics—one philosopher (heather widdows), one psychologist (fiona * fiona maccallum fiona.maccallum@warwick.ac.uk department of psychology, university of warwick, coventry cv al, uk department of philosophy, university of birmingham, edgbaston, birmingham b tt, uk http://orcid.org/ - - - http://crossmark.crossref.org/dialog/?doi= . /s - - - &domain=pdf health care analysis ( ) : – maccallum) and two lawyers (melanie latham and jean mchale)—and was in partnership with the nuffield council on bioethics. the network continues, run by maccallum and widdows, and publishes a twice monthly blog with international reach and recognition [ ]. the network continues to enable collaboration between researchers across disciplinary lines and is becoming a first point of contact for those seeking expertise on issues of beauty. the papers in this special issue are part of the academic reflection and theorising which evolved from the beauty demands network (the network also published a “briefing paper” in june , which was primarily aimed at policy makers and medical practitioners) [ ]. while they stand alone as robust academic papers addressing particular topics, taken together as a body of work and alongside the beauty demands blog and briefing paper, they rep- resent something far broader. they are part of a call to recognise the extent of the rising demands of beauty and just how transformative such demands are of individ- ual’s life projects and plans, social expectations and structures, cultural values and assumptions, and of the institutional and policy frameworks which shape and frame what individuals and groups can be and do. the beauty demands network the purpose of the original ahrc grant was to bring together academics from across disciplines, with policy-makers, practitioners, activists and cultural actors to think collectively and creatively about the changing demands of beauty. there were a number of key questions which the network sought to address and hypotheses which it sought to test and explore. the starting presumption was that the demands of beauty were extending and becoming normalised, with little social or academic critique, and that while research had been carried out in various disciplines and wor- ries expressed in a number of quarters (for instance, the keogh review’s worries about the rise in non-surgical techniques) there had been few attempts to address the phenomena across disciplines and to look collectively as well as individually [ ]. the network positioned itself to explore these rising demands from this starting point as stated in the original proposal: the assumption of the network is that beauty image is becoming ever more demanding and defining of women, and increasingly men, irrespective of their professions. the project will ask whether this is the case, and how this norm is constituted and how it impacts upon women. it will also ask whether the dominant beauty norm is increasingly a global beauty norm, and thus open to less cultural and sub-cultural resistance. the project is especially concerned with the role of technology in this. in particular, that procedures which were once regarded as ‘exceptional’ such as the use of surgery, are now regarded as ‘normal’ or even ‘required’ in certain contexts. other increasingly demand- health care analysis ( ) : – ing beauty requirements include hair removal and ‘non-invasive’ procedures to reduce the appearance of wrinkles. all of these procedures, whether ‘rou- tine’ or ‘exceptional’, require time and effort to maintain, and arguably the ‘minimum’ required is increasing; fewer women go ‘bare faced’ or bare their flesh without hair removal. this project will explore the extent to which beauty norms are changing and how, as well as what this means for individuals, for regulation and for clinical practice. [ ] beauty demands’ assumptions, hypotheses and findings to focus the deliberation of network members the project was organised around four key workshops. the intention was to ensure that key stakeholders engaged across disciplines and beyond academia in order to challenge local norms, whether discipli- nary, institutional or social. the first workshop, held at the university of warwick, focused on body image and how our perception of bodies is changing. participants included philosophers, psychologists, lawyers and cultural theorists, clinical psychologists, counsellors and artists. a key theme of this workshop was the rise of technological fixes to change our bodies, and the way that an image based culture is shaping our expectations. as communication and relationships in a visual and virtual culture evolve so our sense of self changes—with identity increasingly located in the visual self. indeed, as one of us later argued, “in our private and virtual lives we must be camera ready so we can present our best self(ie)” [ , p. ]. this workshop was an important scene set- ting event for the network. it provided a clear framework upon which the rest of the project built and which is still core to the beauty demands network. most impor- tantly it embedded the commitment that cosmetic surgery should not be exception- alised as a separate practice or set of practices, but that it should be conceptual- ised as a beauty practice on a spectrum with other beauty practices. the presented papers on tanning and skin-lightening served as reminders that many of the harms of beauty come from so-called routine practices. the impact of body image on our intimate relationships as well as our sense of self was brought home in discussions of the impact of unrealistic body expectations on sexual functioning and as reflected in the rise of revenge porn. crucial too were the papers which showed the ubiqui- tous, continual and rising nature of the demands, and how normal and normalising these were—a theme which returned in every workshop and became a major finding of the beauty demands network. an early draft of herjeet marway’s paper was pre- sented at this workshop and the final version is the third paper in this volume [ ]. full details of the workshops can be found on the beauty demands website (https ://www.birmi ngham .ac.uk/gener ic/beaut y/event s/index .aspx). https://www.birmingham.ac.uk/generic/beauty/events/index.aspx https://www.birmingham.ac.uk/generic/beauty/events/index.aspx health care analysis ( ) : – the second workshop, held in london at the nuffield council on bioethics, had a more medical focus. participants included surgeons, nurses, general practition- ers (gps), and psychologists, as well as body activists and artists. again a key and emerging theme of this workshop was the importance of ‘normal’, the very different ways in which it is used in different areas of the beauty debate, and why it is such a crucial concept. during the course of this workshop and in the virtual debates before and after, it gradually became clear that the term ‘normal’ had a pivotal role in beauty debates. sometimes it was used overtly normatively—to justify what should be—at other times it was used as if it were a purely descriptive term, although reflec- tion usually revealed that hidden normative assumptions were in play. for example, gps and surgeons reported that ‘not being normal’ was a reason that women often gave for seeking cosmetic surgery. indeed ‘not being normal’ was functioning in the discourse surrounding surgery as an acceptable motivation for seeking surgery and as a justification for why it should be performed (whether asserted by the doctor or the recipient), and as a descriptive benchmark. these three different uses of the term normal were deeply problematic and even contradictory. for instance, ‘normal’ used as a descriptive term functions to deter- mine what surgery is justified. to use the term this way, as a gate-keeper for jus- tified surgery, assumes some measure of objectivity or some shared consensus (at least amongst doctors making the decisions about the normality of a body part). yet, while doctors do make judgements on whether a body part is abnormal (and abnor- mal enough that ‘correction’ is justified) there is in fact no standard for what might be normal for any given body part. for example, and in the context of the rise in requests for labiaplasty by young women, medical textbooks and guidelines fail to give a range for what is normal size for labia and tend to use idealised and stylised representations. similarly, there are no objective criteria of what counts as normal, or average breasts, and indeed breasts come in very many shapes and sizes. in terms of breast functioning, size is immaterial for instance, when it comes to the likelihood of successful breast feeding. accordingly normal is not about functioning; although there may be health reasons to reduce very large breasts which cause back pain and other physical problems. but in practice ‘normal’ refers just to the way breasts look. what looks ‘normal’ is not objective, but largely subjective. in a world where it is the breast with implants that we standardly see—in the media, in adverts and in celebrity social media—then it is likely that we are moving towards a notion of ‘nor- mal’ not as ‘average’ taken across the range of actual breasts, but as ‘the breast we normally see’. this normalises, and even naturalises, the modified breast, such that gradually the unmodified breast is the one which looks abnormal. given that many cosmetic surgeons in practice regard ‘to be normal’ as an acceptable and ‘good’ reason for undergoing surgery, the normative nature of this ‘recipient’ was the term the beauty demands network used most often for those who access cosmetic procedures, in preference to ‘patient’ (which assumes a direct parallel with health-contexts), ‘client’ (which implies simple consumption as if buying such procedures is equivalent to purchasing a product or commodity) or ‘user’ (which has uncomfortable connotations of addiction and is overtly value-laden). we felt recipient, on balance, was preferable as it recognises there is a service being received, but is not passive, as patient is. however, the terminology remains problematic, and not all papers in the volume use this terminology. health care analysis ( ) : – discourse is significant. the extent to which this language has been learnt as a script to access cosmetic surgery merits further research. for instance, surgeons are keen to ensure they do not operate on patients with unrealistic expectations—indeed this is something which the general medical council (gmc) and royal college of sur- geons (rcs) emphasise—but if the learned narrative is “to be normal”, simply ask- ing patients why they want surgery will not reveal such expectations [ , ]. rather they will reply with what they know is acceptable, no matter what they actually feel. if ‘to be normal’ has become one of the acceptable narratives, regarded as an accept- able motivating and justifying reason for engagement in all sorts of beauty proce- dures, then ‘normal’ has lost its descriptive and demarcating function. ‘normal’ has become nothing more than a value-judgement to signify what is desirable—used to access whatever breasts (bigger, smaller, perter, firmer) or labia (tighter, firmer, non-protruding, non-chaffing)—you wish. this is worrying as the current ethi- cal assumptions which ground current practices wrongly assume that normal is a descriptive and realistic assessment. in addition, if normal increasingly functions in this way this may impact on those who fall outside the norm. it may produce an environment in which ever more is required to be ‘normal’, to be just good enough. this makes discrimination against those who cannot or will not conform to the demands of beauty more likely. there is no paper from this workshop in this special issue, but the worries about normalisation went on to become the basis of the core recommendations of the briefing paper [ ]. the third workshop was held at the university of birmingham, and addressed the ‘globalisation of beauty’. participants at this workshop came from cultural studies, gender studies, law, psychology and sociology, and it was also attended by journalists. the workshop addressed the contentious issue of the extent to which beauty ideals are converging across cultures, whether they are western or global, and whether there are pockets of resistance. not surprisingly there were divergent views on the extent to which the ideal was becoming global. however, there was broad agreement that beauty ideals are now negotiated in the context of globalisation and there is significant fluidity between and within communi- ties; the notion that there are lots of culturally distinct and separate ideals was deemed unsustainable. accordingly it is no longer plausible to argue that beauty ideals are mere taste, or to claim that changes to these ideals over time and place are sufficient to deny that there are emerging global trajectories. the rise in the demands of beauty—from daily practices such as skin-lightening and tanning— to more demanding practices such as surgery, is real, can be tracked, and needs serious academic attention. for example, while still a minority activity, the num- bers of people ‘going under the knife’ (or needle) is increasing. definitive data on recipient numbers is notoriously difficult to find, but all measurements suggest that the incidence is rising. the international society of aesthetic and plastic surgery (isaps) annually publishes estimated figures based on plastic surgeons’ survey responses. the total number of surgical and non-surgical procedures car- ried out in was estimated to be . million, rising to . million in [ , ]. of these, over half were non-surgical procedures ( . million); however, as most non-surgical procedures are not carried out by surgeons the total number of these (such as botox and fillers) will be far higher. not only are more people health care analysis ( ) : – having such procedures, but perhaps more importantly more people wish to. one study of women found that over % would undergo cosmetic surgery if they could afford it [ ]. so while there were diverse views about the extent to which global homogenization is happening, there was convergent recognition that beauty is an increasingly dominant global value, and all agreed that there was an exponential rise in the use of cosmetic procedures and beauty practices. the increasingly dominance of beauty as a core value is an issue which andrew edgar takes up in the final paper of this volume [ ]. clearly, the global nature of the beauty industry presents a challenge for regulation which is currently largely at national and regional level. danielle griffiths and alex mullock rise to this chal- lenge in the opening paper of this volume [ ]. first drafts of both these papers were presented at this workshop. the final workshop of the network, held in manchester at mmu, focused on the supposed distinction between routine daily beauty practices, and more extreme prac- tices such as cosmetic surgery. participants included philosophers, psychologists, sociologist, lawyers, and those working on health interventions. the purpose of this workshop was to explore the hypothesis that there is no clear distinction, nor way to distinguish between, practices which are daily and standard, and those which are often considered extreme. this work begun at this workshop, and presented by wid- dows, has been completed in perfect me: beauty as an ethical ideal [ ]. in this volume we take up the related issues of how idealised images shape our perceptions of what is ‘normal’, the first draft of which was presented by maccallum at this workshop [ ]. beauty demands’ policy and practice recommendations a key output of the beauty demands network was the briefing paper (launched in june at the nuffield council on bioethics), to policy-makers and practition- ers [ ]. the recommendations are divided into three sections; first, ethical issues, second, psychological issues and third, governance, regulation and legal issues. the summary of the recommendations are as follows: • to recognise that ‘normal’ is a value judgement and not a neutral or descriptive term • to improve understandings and representations of ‘normal bodies’ • to recognise that consent might be compromised by pressures to conform • to recognise the potential for vulnerability in the beauty context • to develop effective interventions that promote positive body images in school curriculums at all ages • to develop media literacy in school curriculums and in the wider public • to promote diversity of model and mannequin sizes and shapes • to standardise training and qualifications required to administer so-called non- invasive procedures and cosmetic surgery • to harmonise standards for premises in which procedures can be undertaken health care analysis ( ) : – • to set minimum standards for products which can be used in beauty practices • to ensure that informed consent is sought personally by the practitioner carrying out the procedure; for all so-called non-invasive procedures as well as surgical procedures • to require a ‘cooling off period’ for all procedures (cosmetic surgery and so- called non-invasive procedures) • to separate roles of salespersons and advertisers from practitioners performing procedures • to consider changing practice and policy with regard to advertisements to reduce risk of unrealistic expectations • to put in place processes for better data collection, monitoring and reporting measures some of these recommendations, particularly those around consent, data, the need to regulate non-surgical as well as surgical procedures, and the need to ensure sales techniques are not coercive, are very familiar from the keogh review and the recent nuffield council report [ , ]. while policy needs to catch up with these reviews, there is now broad consensus that some action is needed. however, this is not true of all areas. for instance, there is no consensus with regard to whether regulation of advertising works, particularly in an on-line culture, or whether and what interventions in schools have lasting effects and do not compound the prob- lem by highlighting the body further. the two recommendations which are unique to beauty demands and which have not been replicated elsewhere are those about the use of ‘normal’ and the extensive nature of ‘vulnerability’ in beauty. the use, interpretation and perception of what is ‘normal’ was identified as a key ethical concern. as discussed above, the term ‘normal’ is currently used in ways that may appear to be neutral or objective, but are in fact underpinned by value judg- ments. in the full briefing document there are two recommendations around ‘nor- mal’ and ‘normalness’: recommendation: careful use of normal in all contexts. recommendation: improving understandings of normalness (for instance, more literature and material featuring a wide range of breasts and/or other body parts in teaching and medical settings). the second area where beauty demands’ recommendations differ from other reports is that we suggest that the extent of vulnerability when it comes to beauty is far more extensive than policy makes and practitioners have standardly recognised and that this has the potential to undermine informed consent. the recent nuffield council report on cosmetic procedures calls for restricting access to all cosmetic procedures for the under ’s [ ]. however, this assumes, as much of health care policy and practice does, that those who are under are uniquely and particularly vulnerable and in a way which adults are not. a number of papers presented in the beauty demands network suggest that in fact significant vulnerability attaches to beauty at many stages of life. the situation in which people may find themselves can make them vulnerable, even if they might not normally be considered, or consider themselves, as such. when it comes to determining who is vulnerable in beauty health care analysis ( ) : – contexts, it is likely that this does not map to standard medical assumptions. for instance, the psychological evidence shows that those who have low self-esteem and low body-satisfaction are likely to be more vulnerable (less resilient) to pressure to modify their bodies. low body-satisfaction occurs throughout the lifespan and is often connected to, and triggered by, stress factors and life changes (such as divorce, unemployment or bereavement). while there are significant and particularly vulner- abilities which impact upon the young—they are far more likely to have embraced selfie culture and therefore suffer the added pressure of needing to succeed in the virtual world (to be ‘liked’)—they are also likely to conform more to the beauty ideal than older women. as wrinkles and other signs of aging become marks of shame, we might begin to see those who are older and who have more to do to attain the ideal start to suffer more. if this is so, current calls fail to address the real extent of vulnerability in beauty, and if vulnerability is a feature which can undermine the ability to consent, this is a direct challenge to the current reliance of informed con- sent as a way to ensure ethical practice in cosmetic surgery. the full recommenda- tion in the briefing paper is: recommendation: ensure practitioners are trained to recognise the potential for vulnerability, and to understand that vulnerability may well be found in those who would not usually be considered vulnerable. beauty demands’ papers the four papers in this workshop take forward questions raised in the beauty demands network in academically innovative ways. each is an example of how academic research can explore features of the emerging and increasingly dominant beauty ideal and ask about its consequences and implications for how we think about the body and the self and what we might need to do to respond to the rising demands of beauty. the volume opens with a paper by danielle griffiths and alex mullock, “cos- metic surgery: regulatory challenges in a global beauty market”, which addresses cosmetic surgery tourism. they focus on the increased numbers of uk individu- als seeking cosmetic surgery abroad for predominantly financial reasons. recipients travelling for surgery from the uk largely come from working class demographics. griffiths and mullock build on previous arguments that cosmetic surgery should not be regulated as if it were therapeutic surgery and contend that the “medical excep- tion”, which exempts doctors from the scrutiny of the criminal law, should not apply. they argue that the risks of cosmetic surgery are magnified when travelling abroad for a number of reasons: it is more difficult to check the quality of the clinic and the qualifications of the surgeon; insurance and compensation may be more difficult to attain and pursue; informed consent may not be robust and may be compromised by package deals purchased in advance; and after-care will be limited after the recipient returns to the uk. ultimately, griffiths and mullock recognise the limits of the law as a tool for addressing this phenomenon, particularly in the global context. they do not argue for banning this practice, or for excessively restrictive uk legislation as health care analysis ( ) : – they recognise that little is to be gained by driving people to seek cosmetic surgery elsewhere. yet they state: but the legal is not redundant. tighter regulation in the uk, including using the criminal law against surgeons who cause harm when they proceed with risky surgeries, will not prevent people from seeking services abroad. how- ever, a domestic response would hopefully send out a symbolic message that such surgery is potentially dangerous and should therefore be treated with great caution. in addition to making recommendations for a particular regulatory response, griffiths and mullock’s paper shows just how important cross-disciplinary discus- sions are when it comes to addressing the rising demands of beauty. too often pol- icy makers have regarded regulation as merely about managing the risks and harms to recipients. as a result policy-makers have largely ignored the social impact of engagement or the implications for those who do not engage. griffiths and mull- ock do not fall into this trap but recognise that “cosmetic surgery reinforces and heightens concern with body image and culturally prescribed standards of beauty, contributing to a youth culture that disdains aging and the elderly and upholds cul- turally specific standards of beauty”. accordingly they emphasise the importance of regulation and the place which law—particularly symbolic law—has to play in such processes. they make a plea for recognising the importance of “indirect effects” “that would deter such surgery and thwart normalisation by delegitimising it. this would, we argue, make women think twice about seeking cosmetic surgery at home or abroad”. the second paper in the volume is our own contribution, “altered images: under- standing the influence of unrealistic images and beauty aspirations”. in this paper we consider the now frequent calls that altered images be labelled in some way. almost every image we see, whether in print or virtually, is now modified in some way. alterations range “from relatively minor retouching (whitening teeth and eyes, smoothing wrinkles, and erasing blemishes) to more dramatic modification (elon- gating limbs and slimming waists, thighs and arms)”. there have been numerous calls for regulation of such images and recent calls for the labelling of such images. the thinking behind this is that such labelling will alert consumers to the alteration, making them more aware of the artificial nature of the images and so less critical of their own body’s failure to live up to such unrealistic ideals. however, contrary to this hypothesis recent evidence suggests that labelling does nothing to reduce the negative impact on self-esteem which attaches to viewing idealised images and may even heighten negative effects. at first glance this appears counter intuitive: “shouldn’t knowing images are altered reduce the expectation we place on ourselves to be better or perfect?”. yet it is the case that “we continue to hold digitally modi- fied images as ideals even when we are told they are not ‘real’”. in this paper we argue that this result is not as surprising, for psychological and philosophical rea- sons, as it might first appear. the assumption that knowing images are unreal would lead us to discount them as relevant self-comparators turns out not to be the case. on the contrary, labelling results in us paying more attention rather than less to the features of the image which health care analysis ( ) : – have been idealised. accordingly “labelling images as digitally altered exacerbates negative social comparisons with ideal images, which in turn exacerbates criticism of our own appearance”. this psychological phenomenon fits with a philosophical account of beauty as an ethical ideal. if a woman has adopted beauty as her moral framework and judges herself morally with regard to how well she succeeds or fails in beauty then “knowing that beauty ideals are unreal and unattainable does nothing to reduce the wish to attain such ideals”. recognising the place of images in creating the ideals which women strive for as symbols of the selves they want to be, rather than realistic images, is crucial to understanding the demands of beauty. as we put it in the paper: it is this emotional commitment and investment in the ideal (manifested in the extent to which we judge ourselves and others by it) that helps to explain why the images which present us with instances of the perfect ideal do not lose their power simply because we know they are digitally retouched. our imagin- ings of our perfect – or improved or better or good enough – self, the end point of the beauty ideal to which we are striving, has very little to do with what is actually achievable or likely to be achieved. the third paper in the volume, “should we genetically select for the beauty norm of fair skin?” is by herjeet marway. in this paper marway combines a famil- iar topic from beauty discourse—that of the preference for ‘fair’ skin—with the bioethical discourse of genetic selection. she argues that while race is often rec- ognised as significant, beauty is not, and by considering this ‘beauty preference’ through the lens of race the wrong of selection for fair skin is visible. marway focuses primarily on ‘black’ african–american women and ‘brown’ indian women and argues that, despite prominent protest movements, fair skin remains a dominant beauty norm in these groups. she highlights the racial and colour hierarchies that underpin the connections between fairness and beauty and darkness and unattractiveness. she argues that “underwriting all this is a beauty norm for fair skin that exists in particular places and which arbitrarily values particular races or colours because of a history of racism and colourism—ulti- mately this is prejudicial”. having documented the ubiquity of the practice of skin-lightening and the harms which attach to current practices, marway turns to genetic testing and the possibility that individuals may use this technology to select embryos with fair skin. she draws parallels between cases of selection for disability and sex, and argues that in similar ways women may feel pressure to select against darker skin. marway argues that selection for beauty reasons is no less trivial than selection for explicitly racial reasons. her claim is that “selection for fair skin in the pursuit of beauty does include some ideas about what is bet- ter and what benefits might accrue to one’s child that are rooted in some of the problematic [racist] ways discussed”. she argues that selection for beauty cannot be separated from race as, “if the beauty norm for fair skin is selected for, in part, because of the discriminatory hierarchies and stereotypes associated with race or colour then such selection is not insignificant.” accordingly marway concludes that “selection for the beauty norm of fair skin is discriminatory and demanding” and “we should not make such selections in the pursuit of beauty”. health care analysis ( ) : – the final paper in this volume is andrew edgar’s paper, ‘the athletic body’. edgar explores the ways that bodies—in this case the athletic body—carry the capacity for story-telling. in the paper edgar compares the olympian bodies of johnny weissmuller in the s and michael phelps in the early s. the differences between these bodies is striking, with phelps’s characterised by a sculpted look of ‘clean bulk’, which exemplifies the requirements of firmness and smoothness of the contemporary beauty ideal. as edgar notes, this body is not limited to sport but is “prevalent in cinema, fashion and, perhaps crucially, in the advertising of male health and fitness products”. this body—muscled, firm and buff—is a body which is presented as one to which men should aspire: “clean bulk is the norm, against which others are judged, and towards which even non- athletes should aspire”. edgar argues that this body is a normative body which is presented as “the personification of a meaningful life” and he suggests that it is no accident that this apes the superhero body. edgar presents the athletic body as a mythical body (“the sporting monomyth”) which tells a particular story, of a contemporary hero, a story of performance and spectacle. in this fiction: the professional athlete is an autonomous agent. the athlete has made a series of self-defining choices, successfully overcoming obstacles, and thereby realising a coherent and meaningful life. like the superhero they have, ideally, an unerring awareness of the right thing to do…the hero wins. as such, their lives therefore come to exemplify a serious of good and meaningful choices. he concludes that, while dominant, the story that this mythical body is invoked to tell, despite its claims to power, is in fact an impoverished account not only of the body but of the human condition. it is an illusion. it hides the reality of loss which shadows winning in sport, and is challenged by the female sporting body, in which power is transformed into a “sexualised spectacle”, and the illusion of autonomous power crumbles. in an increasingly visual and virtual culture, it is not just the aes- thetic body which is inherently story-telling with regard to meaning and identity, but all bodies. our body becomes the place where we tell our stories, we use it to tell others who we are and even what we are, “we write ourselves – and our insecurities – on our bodies, for our bodies, actual, transforming and imagined, are ourselves” [ , p. ]. the future of beauty demands the ahrc network grant which kicked off the beauty demands network and from which this volume results continues to grow from strength to strength. that beauty matters, and matters more in our visual and virtual culture, is increas- ingly recognised. there is rising public concern about many aspects of the beauty ideal, not least the rise in the demand for cosmetic surgery, the routinisation, nor- malisation and naturalisation of non-surgical procedures, such as botox and lip fillers, and the epidemic of body image anxiety which is debilitating and devastat- ing. beauty demands provided an academic forum for debate beyond disciplinary health care analysis ( ) : – silos, and while it may not have resulted in a single or consensus voice, it has pro- vided an important intervention. beauty demands and its network members are increasingly speaking in public and policy fora, and the need for action, reflection and theorising in this space is every more pressing. we are grateful to the ahrc for the initial funding and to all the network members and partners who continue to be active in driving beauty demands forward. we believe further research and engagement in this area is crucial and beauty demands will continue to be a place of discourse, debate and research for those working in this area, who bring different and divergent perspectives and views to the debate. we look forward to working with beauty scholars, practition- ers, activists and policy-makers in the future and we hope you will enjoy this col- lection of papers. acknowledgements we would like to thank the ahrc for funding the original network, the nuffield council of bioethics, particularly cath joynson, kate harvey and katharine wright, for their partnership, and hca for their patience with the delivery of this volume. funding this study was funded by the arts and humanities research council (grant number ah/ l x/ ). compliance with ethical standards conflict of interest the authors declare that they have no conflict of interest. open access this article is distributed under the terms of the creative commons attribution . interna- tional license (http://creat iveco mmons .org/licen ses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the creative commons license, and indicate if changes were made. references . ahrc grant application for ahrc network grant “the changing requirements of beauty”, available on request from h.widdows@bham.ac.uk. . beauty demands blog. http://beaut ydema nds.blogs pot.com. accessed june , . . beauty demands briefing paper. https ://www.birmi ngham .ac.uk/docum ents/colle ge-artsl aw/ beaut ydema nds/beaut y-deman ds-briefi ng-paper -june- .pdf. accessed june , . . edgar, a. ( ). the athletic body. health care analysis. https ://doi.org/ . /s - - - . . general medical council (gmc). ( ). guidance for doctors who offer cosmetic interven- tions. https ://www.gmc-uk.org/guida nce_for_docto rs_who_offer _cosme tic_inter venti ons_ .pdf_ .pdf. accessed april , . . griffiths, d., & mullock, a. ( ). cosmetic surgery: regulatory challenges in a global beauty market. health care analysis. https ://doi.org/ . /s - - - . . international society of aesthetic and plastic surgery (isaps) the international study on aesthetic/ cosmetic procedures performed in . http://www.isaps .org/media /defau lt/globa l-stati stics / isaps -resul ts-proce dures - .pdf. accessed august , . . international society of aesthetic and plastic surgery (isaps) the international study on aesthetic/ cosmetic procedures performed in . http://www.isaps .org/media /defau lt/curre nt% new s/ globa lstat istic s .pdf. accessed august , . http://creativecommons.org/licenses/by/ . / http://beautydemands.blogspot.com https://www.birmingham.ac.uk/documents/college-artslaw/beautydemands/beauty-demands-briefing-paper-june- .pdf https://www.birmingham.ac.uk/documents/college-artslaw/beautydemands/beauty-demands-briefing-paper-june- .pdf https://doi.org/ . /s - - - https://doi.org/ . /s - - - https://www.gmc-uk.org/guidance_for_doctors_who_offer_cosmetic_interventions_ .pdf_ .pdf https://www.gmc-uk.org/guidance_for_doctors_who_offer_cosmetic_interventions_ .pdf_ .pdf https://doi.org/ . /s - - - http://www.isaps.org/media/default/global-statistics/isaps-results-procedures- .pdf http://www.isaps.org/media/default/global-statistics/isaps-results-procedures- .pdf http://www.isaps.org/media/default/current% news/globalstatistics .pdf http://www.isaps.org/media/default/current% news/globalstatistics .pdf health care analysis ( ) : – . keogh, b. ( ). review of the regulation of cosmetic interventions (keogh review). london: department of health. https ://www.gov.uk/gover nment /uploa ds/syste m/uploa ds/attac hment _data/ file/ /revie w_of_the_regul ation _of_cosme tic_inter venti ons.pdf. accessed april , . . maccallum, f., & widdows, h. ( ). altered images: understanding the influence of unrealistic images and beauty aspirations. health care analysis. https ://doi.org/ . /s - - - . . marway, h. ( ). should we genetically select for the beauty norm of fair skin? health care analysis. https ://doi.org/ . /s - - -y. . molina, a. r., baker, r. h., & nduka, c. ( ). ‘what women want’—the uk’s largest cosmetic surgery survey. european journal of plastic surgery, ( ), – . . nuffield council on bioethics. ( ). the ethics of cosmetic procedures. http://nuffi eldbi oethi cs.org/wp-conte nt/uploa ds/cosme tic-proce dures -full-repor t.pdf. accessed october , . . royal college of surgeons (rcs), professional clinical standards. ( ). “professional standards for cosmetic surgery” https ://www.rcsen g.ac.uk/libra ry-and-publi catio ns/colle ge-publi catio ns/docs/ profe ssion al-cosme tic-surge ry/. accessed april , . . widdows, h. ( ). perfect me: beauty as an ethical ideal. princeton: princeton university press. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/ /review_of_the_regulation_of_cosmetic_interventions.pdf https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/ /review_of_the_regulation_of_cosmetic_interventions.pdf https://doi.org/ . /s - - - https://doi.org/ . /s - - -y http://nuffieldbioethics.org/wp-content/uploads/cosmetic-procedures-full-report.pdf http://nuffieldbioethics.org/wp-content/uploads/cosmetic-procedures-full-report.pdf https://www.rcseng.ac.uk/library-and-publications/college-publications/docs/professional-cosmetic-surgery/ https://www.rcseng.ac.uk/library-and-publications/college-publications/docs/professional-cosmetic-surgery/ the demands of beauty: editors’ introduction abstract the beauty demands network beauty demands’ assumptions, hypotheses and findings beauty demands’ policy and practice recommendations beauty demands’ papers the future of beauty demands acknowledgements references predicting scenic beauty of mountain regions r p u a b c h � � � � a a r r a k g l l p n c a ( h landscape and urban planning ( ) – contents lists available at sciverse sciencedirect landscape and urban planning j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / l a n d u r b p l a n esearch paper redicting scenic beauty of mountain regions ta schirpke a,∗, erich tasser b, ulrike tappeiner c institute for alpine environment, european academy bolzano/bozen, viale druso , i- bolzano, italy institute for alpine environment, european academy bolzano/bozen, italy institute of ecology, university of innsbruck, institute for alpine environment, european academy bolzano/bozen, italy i g h l i g h t s developed method allows predicting scenic beauty of mountain regions. good prediction of scenic beauty (r = . ). near zone contributes to scenic beauty by %. method can be used for decision making and landscape planning. g r a p h i c a l a b s t r a c t r t i c l e i n f o rticle history: eceived november eceived in revised form november ccepted november eywords: is andscape metrics a b s t r a c t scenic beauty of mountain landscapes contributes to human well-being. valuation of natural scenery and specific landscape properties by perception studies is complex and time-consuming. sophisticated spatial analysis tools can support the assessment of scenic beauty by quantitative methods. we implemented an innovative gis-based modeling approach for mountain regions which combines objective methods with perception-based methods. based on viewpoints, spatial patterns of visible landscape were analyzed by means of landscape metrics. a set of landscape metrics were reduced by principal component analysis (pca) to components explaining % of the variance. the components were related to perceived scenic beauty values found through a perception study via stepwise regression analysis. we found that two com- and use erception study ponents, shape complexity and landscape diversity, are positively related to visual quality (r = . ). in the central alps, especially areas above the tree line are characterized by high scenic beauty. abandon- ment of agriculturally used areas implies a loss of scenic beauty, mainly in the valley bottom and in the subalpine forest belt, as a result of urban sprawl and natural reforestation. the gis-based model offers a valid instrument for scenic beauty assessments of mountain regions as a basis for policy making and landscape planning. . introduction humans find great opportunities for recreation and leisure in atural ecosystems (de groot, alkemade, braat, hein, & willemen, ). the demand for outdoor recreation has been growing ontinuously, and especially mountain environments are highly ppreciated by tourists (raitz & dakhil, ) because of scenic ∗ corresponding author. tel.: + ; fax: + . e-mail addresses: uta.schirpke@eurac.edu (u. schirpke), erich.tasser@eurac.edu e. tasser), ulrike.tappeiner@uibk.ac.at (u. tappeiner). - /$ – see front matter © elsevier b.v. all rights reserved. ttp://dx.doi.org/ . /j.landurbplan. . . © elsevier b.v. all rights reserved. beauty, fresh air, varied topography, and forests (beza, ; scarpa, chilton, hutchinson, & buongiorno, ). the cultural landscape of mountain regions has been shaped by hundreds of years of agricultural activities (fischer, rudmann-maurer, weyand, & stöcklin, ) leading to a mosaic of agricultural land, natu- ral grassland and forests. during the last decade, many european mountain regions have become affected by land abandonment (rutherford, bebi, edwards, & zimmermann, ; schneeberger, bürgi, & kienast, ), and non-agricultural sources of income, in particular tourism, have become more important for the local population. particularly the abandonment of alpine pastures and meadows results in natural forest re-growth (sitzia, semenzato, dx.doi.org/ . /j.landurbplan. . . http://www.sciencedirect.com/science/journal/ http://www.elsevier.com/locate/landurbplan mailto:uta.schirpke@eurac.edu mailto:erich.tasser@eurac.edu mailto:ulrike.tappeiner@uibk.ac.at dx.doi.org/ . /j.landurbplan. . . and u & w & e i d t b h b a o c b b s c m h s t ( e t r e v t a b s a c e p o e a f t s f p p e b h o d t l a p m p t v r l u. schirpke et al. / landscape trentanovi, ; tasser, schermer, siegl, & tappeiner, ) hich, however, humans perceive a loss in scenic beauty (hunziker kienast, ). as the recreational quality of a region is to a great xtent linked to its scenic beauty (chhetri & arrowsmith, ), t constitutes a competitive advantage in respect to other tourist estinations. therefore, scenic beauty assessments are an impor- ant aid for planners and stakeholders (ribe, ; tasser et al., ). the scenic beauty of a landscape comes from the interaction etween its biophysical features and the human observer which as led to perception-based and expert-based methods for scenic eauty assessments (daniel, ). perception-based methods ssess community perceptions and analyze perceived scenic beauty n-site or by presenting photographs (arriaza, cañas-ortega, añas-madueño, & ruiz-aviles, ; grêt-regamey, bishop, & ebi, ). although some perception studies found differences etween groups by age, gender, social stratum (hunziker et al., ; tveit, ) or cultural background (zube & pitt, ), many tudies suggest substantial agreement across different groups (e.g. añas, ayuga, & ayuga, ; kearney et al., ; ode, fry, tveit, essager, & miller, ). perception-based assessments have a igh level of reliability (daniel, ), but they are relatively expen- ive, time-consuming and difficult to organize on site (lothian, ). assessments of large complex landscapes are often limited o locations along linear features such as roads, trails, and rivers meitner, ; beza, ). in contrast, expert-based approaches xamine defined visual properties and biophysical features of he landscape by quantitative methods (daniel, ). germino, einers, blasko, mcleod, and bastian ( ) estimated visual prop- rties of rocky mountains landscapes quantifying dimensions of iews, e.g. areal extent, depth, relief, and composition of views in erms of diversity and edge of land cover. de la fuente de val, atauri, nd de lucio ( ) correlated different variables describing scenic eauty, e.g. coherence, legibility, complexity, mystery and diver- ity, to landscape metrics. the major advantage of an expert-based ssessment is its efficiency (lothian, ), which allows the appli- ation for whole regions by using automated procedures. however, xpert-based assessments have not reached the high reliability of erception-based methods because they are extremely dependent n the professional knowledge of the assessor (daniel, ). to benefit from the advantages of each assessment method, sev- ral authors linked perception-based approaches to expert-based pproaches by examining the relationship between landscape pre- erences and landscape patterns by landscape metrics. they found hat diversity indices in particular are positively correlated to land- cape preferences (dramstad, tveit, fjellstad, & fry, ; franco, ranco, mannino, & zanetto, ; hunziker & kienast, ). almer ( ) identified a better relation of scenic beauty to com- osition metrics than to configuration metrics. only few studies xamined the scenic beauty of mountain landscapes using a com- ination of perception-based and expert-based methods. whereas unziker and kienast ( ) examined landscape metrics based n photographs, grêt-regamey et al. ( ) included a three- imensional view analysis but concentrated on only three land-use ypes. in contrast to flat landscapes, where only artificial features ike wind turbines are visible at greater distances (shang & bishop, ), in mountain areas topographic characteristics like slope and spect have to be considered in addition to distance. especially laces of higher elevation than their surrounding area, such as ountain peaks, have long vistas (germino et al., ) and visual roperties as size and perceived landscape color change with dis- ance (bishop, ). while in flat landscapes artificial elements or egetation can block the view, in mountain regions vistas in lower egions such as valley bottoms can be limited by mountains. to estimate scenic beauty for any viewpoint within mountain andscapes, an efficient spatially explicit assessment method that rban planning ( ) – accounts for the implications of topography on view properties, and, at the same time, ensures the high reliability of perception- based assessments is still lacking. to fill this gap, we aimed at developing a modeling approach to predict scenic beauty of moun- tain regions and divided our research into the following steps: ( ) explore relief-dependent visual properties by using a geographical information system (gis), ( ) examine composition and configura- tion of landscape by landscape metrics, ( ) test if perceived scenic beauty can be related to landscape pattern, and ( ) estimate scenic beauty for the central alps, aiming to investigate relationships of land use and scenic beauty. . methods the methodology followed in this paper can be divided into six distinct parts. first, we selected representative study sites for the central alps. second, we introduced distance zones to explore visual properties of mountain regions. third, we determined the necessary input data for the different distance zones. fourth, we conducted a visibility analysis to determine the visible area seen from an observer point by using gis. the visible area was then intersected with the land-cover maps of each distance zone and land cover mosaics were created. fifth, we calculated landscape metrics based on the land cover mosaics. finally, to assess human perceptions, we carried out a perception survey to obtain perceived scenic beauty values. we related the perceived scenic beauty val- ues to landscape metrics by a regression analysis to predict scenic beauty for any viewpoint. . . study sites we developed our model for the greater region of the central alps. to cover geographical variations of relief and land cover, we selected four minor study sites (fig. ): ( ) lech valley, austria (municipalities of gramais, hinterhornbach, pfafflar and stan- zach); ( ) stubai valley, austria (municipalities of neustift im stubai and fulpmes); ( ) pustertal, italy (municipalities of gsies, rasen-antholz, sand in taufers, prettau) and ( ) vinschgau, italy (municipalities of glurns, graun im vinschgau, mals, schluderns). their landscapes are mainly composed of forest and grassland with different management intensities, from intensively used grassland in lower regions to alpine pastures and abandoned land, mostly in regions above the tree line, with higher areas covered by rocks and glaciers. the study sites belong to the northern central european climate zone except for the vinschgau, which is part of the central alpine arid climate zone (fliri, ). they are characterized by dif- ferent relief properties and have diverse land cover distributions (table ). . . distance zones in mountain landscapes with long vistas, object appearance, color difference, and lightness contrast of an object and its surroundings decrease with increasing distance, leading to less dis- cernible detail (bishop, ). to account for the effect of distance on the perception of size and color, several authors introduced distance zones and divided the landscape into foreground, mid- dle ground and background (bishop & hulse, ; de la fuente de val et al., ; germino et al., ). while bishop and hulse ( ) limited the viewshed analysis to just km from the obser- vation point, germino et al. ( ) defined background as up to km. in contrast to flat landscapes, where only elements rising from the landscape are visible, the landscape in mountain regions can be seen in top view from viewpoints at higher positions than the surrounding area. we adapted the distance zones to the high u. schirpke et al. / landscape and urban planning ( ) – fig. . location of study sites. table areal extent, relief-dependent properties, and land cover distribution of the four study sites. study site area [km ] elevation [m a.s.l.] slope [◦ ] land cover distribution [%] min max mean min max mean agricultural area forest settlement lech valley < v t d a • f v ( stubai valley pustertal vinschgau ariability of landscape pattern and relief properties of the cen- ral alps. based on the distinguishability of landscape elements, we efined three distance zones from a viewpoint within the study rea (fig. ): near zone, up to . km. details of single features such as trees or buildings are clearly identifiable. ig. . visible area intersected with land use of the three distance zones from a iewpoint (black dot). (a) near zone ( – . km), (b) middle zone ( . – km) and c) far zone ( – km). < < < • middle zone, from . to km. single elements merge, e.g. single trees form a forest or buildings make up a village. • far zone, up to km. although views of up to km are pos- sible from mountain peaks (germino et al., ), good visibility outside population centers in europe is considered as – km, and longer vistas occur only under rare occasions (horvath, ). the number of perceivable land-cover classes decreases, whereas edge and outline of the landform still play a major role for the perception of space. the different distance zones are used to select input data with diverse spatial and thematic resolution for the gis-based model. the visibility analysis within the model was performed taking into account scale and perceived color dependencies from a distance. the distance zones were also applied for attributing weights to the pictures of the perception survey. . . data collection for each distance zone, spatial information was selected and/or aggregated with regard to content and spatial resolution. digital elevation models (dem) were applied to determine visible area and to derive relief-dependent variables. for the near zone, we used dem with a resolution of m × m, provided by the tyrolean information system (tiris, ©land tirol) of the province of tyrol and the autonomous province of bolzano-south tyrol. for the mid- dle and far zone, elevation was obtained from a dem consisting of processed data from the shuttle radar topography mission (srtm) with a resolution of arc-seconds (jarvis et al., ). the resolution was adapted to m × m for the middle zone and resampled to km × km for the far zone. and u m t d a n i m f s g t l s g b p t m t s d o l i z f g i g s p & t k o a n b t w l h c s t t c o g v s v e & e v t o b u. schirpke et al. / landscape habitat and land cover maps were used to calculate landscape etrics. for the near zone, the analysis was performed using habi- ats which are essential in the analysis of species and landscape iversity (dudley, baldock, nasi, & stolton, ). the habitat map s applied by tasser, ruffini, and tappeiner ( ) is a register of atural, near-natural, and artificial habitats, e.g. grassland habitats n valleys are distinguished from those on the subalpine belt, or anaged coniferous forests are different from mixed or deciduous orests. the variety of habitats helps to capture landscape diver- ity. structural elements like point or linear landscape features (e.g. roves, hedges, single trees, banks, debris areas) explain landscape exture (michel, burel, legendre, & butet, ) and help to express andscape quality better (weinstoerffer & girardin, ). a land- cape structure map was intersected with the habitat map, both enerated for the study areas from orthophotos (scale : , ) y on-screen digitizing in a gis. additionally, land cover was sup- lemented by three spatial datasets: major streams selected from he river network; plus roads, both provided by the tyrolean infor- ation system (tiris, ©land tirol) of the province of tyrol and he autonomous province of bolzano-south tyrol, and mapped ingle settlement points. all datasets were converted to raster atasets with a spatial resolution of m × m and merged into ne dataset. for the middle and the far zone, we used corine land cover (clc ) seamless vector database (eea, ). based on the ow number of land cover classes in the central alps and accord- ng to the distinguishability of elements as defined for the distance ones, the clc-level- classes were aggregated into six classes or the middle zone: forest, grassland, settlement, rock, water and lacier. for the far zone, rock was included in the grassland because t is often covered by sparse vegetation and therefore less distin- uishable from alpine grassland with increasing distance. water, ettlements and glaciers constitute important landscape elements. resence of water has a positive influence on scenic beauty (bishop hulse, ) and offers a wide range of recreational activi- ies. glaciers are also important tourist attractions (scott, jones, & onopek, ). in contrast, large settlements have negative effects n scenic beauty in mountain regions (grêt-regamey et al., ) nd perceived scenic beauty is strongly correlated with natural- ess (lamb & purcell, ). color differences, which are greater etween the bright color of settlements and glaciers with vegeta- ion than between different vegetation types, and the reflection of ater surfaces also support visibility and distinguishability of these andscape elements from greater distances (litton, ; garcía, ernández, & ayuga, ). to account for the large scale of the orine land cover map and to include all areas of the classes water, ettlements and glaciers, these classes were treated as a priority in he conversion from polygon to raster datasets. . . visibility analysis visual properties of the landscape are determined by the loca- ion of a viewpoint. rather than any specific restricted view as aptured by photographs, the surroundings affect the perception f the visual environment in their entirety (meitner, ). a geo- raphic information system is a suitable tool for analyzing ◦ iews from a viewpoint. due to the topography of mountain land- capes, some areas of the landscape may not be visible from the iewpoint. by using an algorithm for estimating whether or not ach target cell is within the observer’s line-of-sight (kim, rana, wise, ), viewsheds can be calculated and non-visible areas xcluded. a dem does not take into account feature height from egetation or buildings which can narrow or completely block he view. heights of mapped surface features were superimposed nto the dem and a digital surface model (dsm) was generated y adding the feature heights to the ground elevation (dem). an rban planning ( ) – average height of m was assigned to forest (wallentin, tappeiner, strobl, & tasser, ) and m to shrubs (dullinger, dirnböck, & grabherr, ), while the average height of buildings was estimated as m. we created a set of viewpoints for all study sites (lech valley ; stubai valley ; pustertal ; vinschgau ), regularly distributed over the whole study area, by placing a viewpoint every m to account for the landscape variability but to maintain feasible computing time. each view- point was assigned a unique id in order to relate all non-spatial information to the specific viewpoint. viewpoints within forest and settlement areas were excluded from viewshed analysis because of viewing restrictions. for all other viewpoints, three viewsheds, one for each distance zone, were computed, based on the dsm using an eye level of . m. to obtain the visible land cover for each dis- tance zone, viewsheds were intersected with the corresponding land cover datasets (fig. ). a mosaic of the three resulting datasets was created for further analysis because the different zones are seen from the viewpoint as one scene belonging together. to repeat the analysis for an arbitrary number of viewpoints, calculation was automated by generating a gis-based model writ- ten in python . (python software foundation, nh, usa) and using standard routines provided with arcgis . tm (esri, redlands, ca, usa). . . landscape metrics landscape metrics were calculated for the land cover mosaic using fragstats version . . (mcgarigal et al., ) which includes a variety of metrics describing area, patch, edge and shape properties as well as diversity on three different levels: patch, class or landscape. selection of landscape metrics can be based on exper- tise or on statistical approaches (lausch & herzog, ; riitters et al., ). in line with comparable studies (dramstad et al., ; franco et al., ; hunziker & kienast, ; palmer, ), we selected landscape metrics at landscape level (see appendix a for details). the land cover mosaics of the viewpoints were all of the same size. non-visible areas, classified as background, were assumed to be ‘outside’ the landscape of interest and had no influence on area-based metrics (mcgarigal et al., ). the selected landscape metrics were subsequently reduced by principal component analysis (pca). . . perception survey landscape metrics can describe landscape in terms of hetero- geneity, diversity, and composition, but they do not reflect human perceptions. the areal extent of the visible landscape is positively correlated to perceived scenic beauty (germino et al., ; sander & manson, ) and can be assessed by area-based metrics. land- scape metrics were related to human perceptions through a survey investigating people’s perception of scenic beauty. the survey was based on a questionnaire presenting a set of photographs and con- taining six series related to ( ) landscape structure, ( ) settlement pattern, ( ) forest pattern, ( ) presence of water, ( ) forest density, and ( ) view zones. each series was made up of four images: one real photograph and three different versions of the original photograph modified with adobe photoshoptm. a seventh series was added at the end of the questionnaire repeating the six original photographs from series to . additionally, we included questions related to demographical information (age, gender, origin). the questionnaire was translated in german and italian by a professional translator. the respondents were selected in public locations in the study sites on the basis of an equal distribution of age, gender, origin (inhabi- tants and tourist) to represent perceptions of the whole community (lothian, ). a total of persons were interviewed by pre- senting the questionnaire. the respondents were asked to rank u. schirpke et al. / landscape and urban planning ( ) – g diff t a q n a s w t p t t i v m p m a t z s w b u t c s fig. . mean scenic beauty values of picture series , representin he four pictures of each series according to scenic beauty (from = least beautiful to = most beautiful). the response rate was %, nd the respondents employed in average – min to fill out the uestionnaire. the rankings of the six different picture series are ot comparable with each other because each series is related to specific theme and the pictures were ranked only within each eries. to compare the different themes represented by series – , e used the seventh series, which repeated the six original pho- ographs from series to . the seventh series consisted of six ictures which led to a ranking scale ranging from = least beautiful o = most beautiful. to obtain comparable scenic beauty values for he series – , we calculated a modified scenic beauty value for each mage by multiplying each original value with the scenic beauty alue of the related photograph of series . the sixth series was anipulated to obtain different combinations of the view zones: icture shows all three zones, picture represents the near and iddle zone, picture shows the near zone, and picture contains ll three zones but has no foreground elements (fig. ). to quan- ify the influence of each view zone, we assigned a weight to each one. first, we computed a scenic beauty value for each zone by ubtracting scenic beauty value of the pictures. subsequently, the eight of each zone was calculated by dividing each mean scenic eauty value by the scenic beauty value of all zones to obtain val- es between and (table ). we used these weights to calculate able alculation of mean scenic beauty value for each view zone, based on mean scenic beauty cenic beauty value by the scenic beauty value of all zones. view zone calculation near zone picture ( . ) middle zone picture ( . ) subtracted from picture ( . ) far zone picture ( . ) subtracted from picture ( . ) all zones picture ( . ) erent view zones ( for least beautiful and for most beautiful). the total weighting factors for all images of the questionnaire. after visually identifying the number of view zones of all images accord- ing to the distinguishability of landscape elements as defined in section . , we obtained a total weighting factor for each image by summing up the weights of the contained view zones. finally, the weighting factor was applied to the modified scenic beauty val- ues of each picture to take into account the number of view zones present and their influence on scenic beauty. all photograph positions were geo-referenced in the field with gps. by setting the appropriate view angle and direction of the picture, the views were located on the land cover map (fig. ). non- visible areas were excluded in calculating the viewshed based on the dsm from the position of the photograph. according to the dif- ferent versions of the original photographs, also different land cover maps were created. based on the adapted land cover maps, land- scape metrics were calculated for all picture views of the survey. . results . . perception survey the survey suggests that view zones play an important role for the perception of scenic beauty. the higher the number of visi- ble view zones, the better the picture was liked, and foreground values of picture series (see fig. ). weight was obtained by dividing each mean mean scenic beauty value weight . . . . . . . u. schirpke et al. / landscape and urban planning ( ) – f ap ove m ible ar e c s b ( i a c s o c e e f s ig. . (a) the original photograph and (b) the same view in google earth with a m ap and the viewshed delimitated by setting view angle and direction. (d) non-vis lements were preferred to the middle and far zone (fig. ). by cal- ulating the weights of each zone, we assessed their influence on cenic beauty. while the near zone contributes by % to scenic eauty, the middle zone reaches % and the far zone only % table ). the distribution of the scenic beauty values for the mages is shown in fig. . . . statistical analysis for the viewpoints, we calculated landscape metrics nd selected explanatory variables by means of a principal omponent analysis (pca) with varimax rotation. the rotated, tandardized components are described by the covariance of the riginal variables and reflect the input variables in few but signifi- ant variables that are absolutely independent (riitters et al., ). leven components with an eigenvalue above were extracted and xplain % of the total variance (appendix b). the first and fourth - - - - - - - - - - - landscape structure settlement pattern forest patte m e a n s c e n ic b e a u ty v a lu e pictu original preference score modified prefere most beautiful least beautiful ig. . mean scenic beauty value for each image, showing original, modified (multiplied cenic beauty value weighted by the view zones). rlay. (c) the position of the viewpoint (yellow circle) was placed on the land cover eas were excluded. components consist mainly of area metrics quantifying the area and extent of patches. whereas the second component comprises dif- ferent types of metrics expressing complexity of patches within landscape, the third component includes only diversity metrics representing richness and evenness to quantify diversity of land- scape. the fourth component consists of different area metrics. components five, seven and eight are dominated by different shape metrics describing landscape configuration by representing the complexity of patch shape, patch size and patch compaction. the sixth component contains different indices describing landscape fragmentation. components nine and ten include shape metrics, while the eleventh component is represented by the number of patches. based on the scenic beauty values of the perception survey and the landscape metrics related to the pictures, we applied a step- wise linear regression analysis to build a model for estimating scenic beauty. scenic beauty values were entered as a dependent - - - - - - - - - - - - - rn presence of water forest density view zones re number nce score weighted preference score with related photograph of series ) and weighted scenic beauty value (modified u. schirpke et al. / landscape and urban planning ( ) – table linear regression result with beta-coefficients and significance of the components. unstandardized coefficients unstandardized coefficients t sig variable b seb beta − v p b ( c t w f a w o v a ( u i r t c ( u b s s m d l t s h b ( w i a p b e ( & r f e v w o component . . component − . . ariable, while the eleven selected components were used as inde- endent variables. the model identified two predictors of scenic eauty (table ) and a good level of prediction was achieved r = . , adjusted r = . ). the first predictor corresponds to omponent (appendix b) with highest loadings for shape and frac- al index distribution representing shape complexity. component was selected as second predictor expressing landscape diversity ith high loadings for all six diversity metrics and negative loading or contagion. . . scenic beauty scenic beauty was estimated for all viewpoints outside forests nd settlement areas by applying the regression model. viewpoints ithin forests returned scenic beauty values from the survey (series ). viewpoints within settlement areas, which were less than % f all viewpoints, were set to no data because no scenic beauty alues were available from the survey. finally, area-wide maps with raster size of m × m were created for all study sites (fig. ). scenic beauty of the viewpoints ranges between . and . table ). to examine the spatial variations of scenic beauty, we sed landscape units as applied by tasser et al. ( ). while sim- lar land cover does not always correspond to the same elevation ange for all study sites, due to diverse climate and agricultural use, he landscape units reflect land cover related to elevation: ( ) agri- ulturally used valley bottom, ( ) agriculturally used valley slopes, ) montane forest belt, ( ) subalpine forest belt, ( ) agriculturally sed alpine pastures, ( ) natural alpine grassland, and ( ) nival belt. ased on the scenic beauty maps and the delimitation of the land- cape units, we calculated mean values for each unit of all study ites (table ). generally, viewpoints in the valley bottom indicate ean values of scenic beauty or below and landscape pattern is ominated by settlements and grasslands but the visible area is imited by slopes, trees, or buildings (fig. a). the forest belt (mon- ane forest and subalpine forest belt) is characterized by very low cenic beauty due to the view being impaired by trees (fig. b). igh scenic beauty can be found for viewpoints above the forest elt, especially within natural alpine grassland and the nival belt fig. c). the visible area of viewpoints above the tree-line increases ith increasing elevation. the viewsheds are mostly character- zed by complex topography, heterogeneous landscape patterns of lpine pastures in the vicinity, and more homogeneous landscape atterns in the distance. . discussion and conclusions daniel ( ) indicated that, in contrast to just perception- ased methods (e.g. arriaza et al., ; cañas et al., ; hunziker t al., ; zube & pitt, ) or purely expert-based approaches e.g. bishop & hulse, ; germino et al., ; herbst, förster, kleinschmit, ), merging the two opposing approaches could esult in a more effective approach that better represents landscape eatures and human judgments. accordingly, our gis-based mod- ling approach combined an automated assessment of the specific iew properties of mountain landscapes and landscape patterns ith a perception-based method, investigating human perceptions f scenic beauty. in a first step, the area seen from a viewpoint was . . . . − . . examined and, by considering different distance zones, the model accounted for the influence of distance on perceived size, shape, and color of landscape features. the visible area was intersected with land-cover maps, and landscape patterns, expressed by landscape metrics, were related to perceived scenic beauty out of a percep- tion survey by a regression analysis. in line with other studies (de la fuente de val et al., ; dramstad et al., ; hunziker & kienast, ; palmer, ), our results confirm the relationship between landscape pattern and scenic beauty. we found that scenic beauty is positively correlated to complexity of patch shape, diversity and structural richness of landscape, whereas large homogeneous areas reduce scenic beauty. the regression model was developed and established for our study region, the central alps. in contrast to other studies in the european alps (grêt-regamey et al., ; hunziker & kienast, ) our model can be applied for any viewpoint in mountain regions within europe, which is considered a human entity, shar- ing common area, culture and behavior patterns (jordan-bychkov & bychkova-jordan, ). thus, the scenic beauty of any view- point can be compared to all other points throughout europe. the gis-based model can also easily be transferred to other regions with similar topographic properties all over the world. it might be necessary to repeat the perception study for other cultural regions where people might perceive scenic beauty differently (zube & pitt, ). although the perception of scenic beauty can vary between diverse social groups or different generations within one landscape region (dramstad et al., ; hunziker et al., ; tveit, ), landscape variations are generally much greater than the variations between observer’s judgments (daniel, ). input data are based on digital elevation models and land cover maps, which are usually available for most areas in europe and comparable satellite-based data exist for many regions world-wide. there are no restrictions regarding spatial and non-spatial resolution of the data. availability of high resolution data used for the near zone is more difficult and might necessitate new mapping. the high resolution data can be substituted e.g. by corine land cover (eea, ) for first assess- ments but lower resolution of input data reduces the quality of the model and smoothes the values for scenic beauty. another advan- tage of our method is that scenic beauty can be predicted for any viewpoint which allows different applications: ( ) it is possible to perform area-wide mapping by distributing viewpoints over the whole area, or ( ) to explore selected zones, for instance those of touristic interest, along roads or hiking trails by placing the view- points along defined features. the quality of assessments depends on the resolution of the input data, which determines the highest possible density of viewpoints because view properties and land- scape composition are highly variable and can change within very short distances. in comparing scenic beauty of diverse landscape units, major differences can be observed between viewpoints above the forest belt, characterized by high scenic beauty, and viewpoints within the forest belt, to which low scenic beauty was attributed. supported by ribe ( ), the survey indicated that structure and diversity influence the perception of scenic beauty in timber stands. open forests are generally preferred. on the other hand, forests are highly appreciated for recreational activities and are related to spiritual, esthetic, cultural, and educational values (scarpa et al., ). close u. schirpke et al. / landscape and urban planning ( ) – lley a t l u h a l f g v p t m f fig. . scenic beauty of (a) lech valley, (b) pustertal, (c) stubai va o average scenic beauty was found for the agriculturally used val- ey bottom and the natural alpine grassland belt. in these landscape nits, landscape pattern and structure are strongly influenced by uman activities. in many alpine regions, considerable changes in griculture and forestry could be observed (rutherford et al., ). and abandonment mainly affected alpine pastures, and natural orest re-growth leads to altered landscape patterns (sitzia et al., ), a general shift from a patchy mosaic toward a more homo- eneous scenery. the increase in forest not only means restricted iew and a loss of viewpoints but affects scenic beauty of any view- oint, because scenic beauty is conditioned by the composition and able ean values of scenic beauty for different landscape units: ( ) agriculturally used valley orest belt, ( ) agriculturally used alpine pastures, ( ) natural alpine grassland, and ( ) ni landscape unit area [km ] mean elevation [m a.s.l.] scenic beauty (n = ) mean . . . sda . . . minimum . . . maximum . . . a standard deviation. nd (d) vinschgau. high values correspond to great scenic beauty. pattern of the whole visible area. as a consequence, a decrease of scenic beauty, especially along hiking tracks, might affect the attractiveness of the area. resulting maps offer a basis for various applications, especially in landscape planning or tourism geogra- phy. the gis-based model can support scenic beauty assessments in the decision making process for future policies or to evaluate already implemented measures, e.g. tasser et al. ( ) emphasize that mountain farming is important to maintain the cultural land- scapes of tourist destinations and abandonment of agricultural land can be avoided by payments for landscape preservation. regarding the europe strategy, the common agricultural policy (cap) bottom, ( ) agriculturally used valley slopes, ( ) montane forest belt, ( ) subalpine val belt. high values correspond to great scenic beauty. total . . . . . . . . . . . . . . . . . . . . u. schirpke et al. / landscape and urban planning ( ) – used p v l g w b s s m a i fig. . typical landscape patterns seen from viewpoints in (a) the agriculturally roposes to relate financial support in the future to ecosystem ser- ices (european commission, ). as cultural ecosystem services ike the recreational value are often expressed by scenic beauty (de root et al., ), our proposed gis-based model allows region- ide assessments for evaluating payments for ecosystem services. y calculating scenic beauty maps based on future land-use/-cover cenarios, future impacts can be visualized and management deci- ions adapted. for the tourism sector in particular, our proposed odel offers great potential to strengthen the competitiveness of region by preserving the landscape or by creating the necessary nfrastructure to access places of great scenic beauty. acronym landscape metrics ta total area np number of patches pd patch density lpi largest patch index te total edge ed edge density lsi landscape shape index area mn mean patch area distribution area am area-weighted mean patch area distribution area md median patch area distribution area ra range patch area distribution area sd standard deviation patch area distribution area cv coefficient of variation patch area distribution gyrate mn mean radius of gyration distribution gyrate am area-weighted mean radius of gyration distribution gyrate md median radius of gyration distribution gyrate ra range radius of gyration distribution gyrate sd standard deviation radius of gyration distribution gyrate cv coefficient of variation radius of gyration distribution shape mn mean shape index distribution shape am area-weighted mean shape index distribution shape md median shape index distribution shape ra range shape index distribution shape sd standard deviation shape index distribution shape cv coefficient of variation shape index distribution frac mn mean fractal index distribution frac am area-weighted mean fractal index distribution frac md median fractal index distribution frac ra range fractal index distribution frac sd standard deviation fractal index distribution valley bottom, (b) the subalpine forest belt, and (c) the natural alpine grassland. acknowledgements we would like to thank the three anonymous reviewers for help- ing to improve the manuscript. we also thank brigitte scott for language editing. special thanks to sonja hölzler who has carried out the perception survey, as well as to everyone who partici- pated in the preference study. this study was supported by the era-net biodiversa, with the national funder fwf, part of the biodiversa call for research proposals and the kulawi project (interreg iv – eu project (agri)cultural landscape – strategies for the cultural landscape of the future, project n. , cup: b d ). appendix a. variations of landscape metrics for the viewpoints. mean min max s.d. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . a w b u. schirpke et al. / landscape and urban planning ( ) – acronym landscape metrics mean min max s.d. frac cv coefficient of variation fractal index distribution . . . . para mn mean perimeter-area ratio distribution . . . . para am area-weighted mean perimeter-area ratio distribution . . . . para md median perimeter-area ratio distribution . . . . para ra range perimeter-area ratio distribution . . . . para sd standard deviation perimeter-area ratio distribution . . . . para cv coefficient of variation perimeter-area ratio distribution . . . . contig mn mean contiguity index distribution . . . . contig am area-weighted mean contiguity index distribution . . . . contig md median contiguity index distribution . . . . contig ra range contiguity index distribution . . . . contig sd standard deviation contiguity index distribution . . . . contig cv coefficient of variation contiguity index distribution . . . . pafrac perimeter-area fractal dimension . . . . contag contagion . . . . pladj percentage of like adjacencies . . . . iji interspersion & juxtaposition index . . . . cohesion patch cohesion index . . . . division landscape division index . . . . mesh effective mesh size . . . . split splitting index . . . . pr patch richness . . . . prd patch richness density . . . . rpr relative patch richness . . . . shdi shannon’s diversity index . . . . sidi simpson’s diversity index . . . . msidi modified simpson’s diversity index . . . . shei shannon’s evenness index . . . . siei simpson’s evenness index . . . . msiei modified simpson’s evenness index . . . . ppendix b. rotated component matrix. selection of the landscape metrics by means of principal component analysis (pca) ith varimax rotation and kaiser normalization. rotation converged in iterations. the resulting components are described y the covariance of the ingoing variables. all values above . or beyond − . are displayed in bold. component communalities variablesa cumulative % of variance explained . . . . . . . . . . . ta − . − . − . . − . . − . . . − . . . np . . . . . . − . . . . . . pd . . . − . − . − . − . . − . . . . lpi . . − . . . − . . . . . . . te − . − . . . . . − . . . . . . ed . . . − . . . . . − . . . . lsi − . . . . . . − . . . . . . area mn − . − . − . . − . . − . . − . − . − . . area am − . − . − . . − . − . . . − . − . − . . area md − . . − . . . . − . − . − . − . . . area ra − . − . − . . − . − . − . . . − . . . area sd − . − . − . . − . − . − . . − . − . − . . area cv . . − . . . − . − . . . . . . gyrate mn − . − . − . . − . . − . . − . − . − . . gyrate am − . − . − . . − . − . − . . . − . . . gyrate md − . − . − . . − . . − . − . − . − . . . gyrate ra − . − . − . . . − . − . . . . . . gyrate sd − . − . − . . − . . − . . . − . − . . gyrate cv . − . − . . . − . − . . . . . . shape mn − . − . . . . − . . . − . − . − . . shape am − . . . . . − . . . − . . . . shape md − . − . . − . − . − . . . . − . − . . shape ra . . . − . . . − . . − . . . . shape sd . − . . . . − . . . − . − . − . . shape cv . − . . . . − . − . . − . . . . frac mn . . . − . . − . . . . . − . . frac am . . . . . − . . . − . − . . . frac md . . . − . . − . . . . . . . frac ra . . . − . . . . − . . . . . frac sd . . . − . . − . . − . . . − . . frac cv . . . − . . − . . − . . . − . . para mn . . . − . . − . − . − . . . . . para am . . . − . . − . . . − . . . . a r a b b b c c d d d d d d e e f f u. schirpke et al. / landscape and urban planning ( ) – component communalities variablesa para md . . . − . . − . − . − . − . . . . para ra . − . − . − . . . . − . . . . . para sd . . − . − . . . − . − . . . − . . para cv − . − . − . . − . . − . . . − . − . . contig mn − . − . − . . − . . . . − . − . − . . contig am − . − . − . . − . . − . − . . − . − . . contig md − . − . − . . − . . . . . − . − . . contig ra . − . − . . . . . − . . . . . contig sd . − . − . − . . . − . − . . . − . . contig cv . . . − . . − . − . − . . . . . pafrac . . . − . . − . . . − . . . . contag . − . − . . − . − . − . − . . . − . . pladj − . − . − . . − . . − . − . . − . − . . iji . . . − . . − . . − . − . − . . . cohesion − . − . − . . − . − . − . . . − . − . . division − . − . . − . . . − . − . − . − . − . . mesh − . − . − . . − . − . . . − . − . − . . split − . − . . . . . − . − . . . . . pr . . . − . . . . . . . . . prd . . . − . − . − . − . . − . . − . . rpr . . . − . . . . . . . . . shdi . . 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( ). understanding alpine tree line dynamics: an individual-based model. ecological modelling, , – . pattern and intensity to landscape quality: use of a landscape indicator. ecolog- ical modelling, , – . zube, e. h., & pitt, d. g. ( ). cross-cultural perceptions of scenic and heritage landscapes. landscape planning, ( ), – . predicting scenic beauty of mountain regions introduction methods . study sites . distance zones . data collection . visibility analysis . landscape metrics . perception survey results . perception survey . statistical analysis . scenic beauty discussion and conclusions acknowledgements appendix a variations of landscape metrics for the viewpoints. appendix b rotated component matrix. selection of the landscape metrics by means of principal component analysis (pca) ... references la belleza del código. el desarrollo de html = the beauty of the code. the rising of html artefactos vol. , n.º , - diciembre eissn: - vol. , - raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - abstract thanks to the growth, development and popularization of world wide web, its technological development has a greater importance in society due to the growing embedding of both of them. our aim in this article is to describe, to characterize and to analyze the process of rising and development of the new web hypertext standard; html . at the same time we explore this process in light of various theories about technology and society. we also pay particular attention to world wide web users and the general la belleza del código. el desarrollo de html the beauty of the code. the rising of html raúl tabarés gutiérrez fundación tecnalia research & innovation faraondemetal@gmail.com fecha de aceptación definitiva: / / resumen gracias al crecimiento, desarrollo y po- pularización de la world wide web, su desarrollo tecnológico goza de un ma- yor protagonismo en la sociedad, debi- do a la creciente integración de ambas. nuestro ánimo en este artículo es des- cribir, caracterizar y analizar el proceso de creación y desarrollo del nuevo es- tándar web de hipertexto; html . al mismo tiempo, exploramos este proce- so a la luz de varias teorías que aúnan tecnología y sociedad. mailto:faraondemetal@gmail.com raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd . introducción actualmente, la creación y desarrollo de estándares web está afrontando un punto de inflexión debido a la mayor presencia e influencia que tienen en la sociedad, tanto los dispositivos móviles como los medios sociales. si bien es cierto que la world wide web es una tecnología que a su vez se basa en tres tecnologías, que son; el protocolo http (hypertext transfer protocol), el localizador uri (unified reference indentificator) y el lenguaje de marcado html (hypertext markup language). constatamos que solamente esta última ha afrontado recientemente, grandes cambios en su desarrollo tecnológico y para el cual, puede entreverse un buen número de interrelacio- nes sociales en su conceptualización y desarrollo. por lo tanto, creemos que su estudio desde un punto de vista que auné tecnología y sociedad, puede ser de sumo interés. este artículo describe el origen y desarrollo de html (hypertext markup language), enuncia sus características más disruptivas y analiza desde un punto de vista social cuales han sido sus principales hitos. nuestro ánimo en este artículo es contrastar teorías que explican la dinámica social de la usage of «social media». we suggest that users influence web standards particularly, and technological development too through these kinds of new technologies. también prestamos especial atención a los usuarios de la world wide web y al uso que éstos hacen de los «social media» o «medios sociales». sugerimos que los usuarios, a través de estas apli- caciones, ejercen una influencia en el desarrollo tecnológico de la web y de los estándares en particular. palabras clave: world wide web; web; internet; tim berners-lee; html; html ; css ; javascript; scot; tecno- logía autónoma; innovación; innovación de usuario; innovación abierta; historia social media; usuario; navegador web; whatwg; api; difusión social; innova- ción social. raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd tecnología (como el modelo scot), con otras que enuncian su pérdida de control por parte de la sociedad (como la tecnología autónoma) y al mismo tiempo evidenciar el papel cada vez más importante que juegan los usuarios en el desarrollo tecnológico y de estándares. sugerimos que los usuarios son una de las fuentes de la innovación tecnológica y ejercen una gran in- fluencia a la hora de desarrollar estándares. . el desarrollo de html . . la creación de html el nacimiento de html constituye un punto de inflexión grande, en el modo que se desarrollan los estándares web. el origen de html tiene su origen en una «pequeña revolución» de profesionales de compañías priva- das, disconformes con el rumbo que había decidió tomar la organización que vela por el desarrollo de los estándares, el w c. un grupo de desarrolladores de la fundación mozilla y de opera software, a los que se les unen más tarde profesionales de apple, fundan en el web hypertext application technology working group (whatwg), al margen del w c (franganillo ). este hecho sucede en junio de , cuando el w c alberga un se- minario sobre «web applications and compound documents» . en esta conferencia se dieron cita distribuidores de navegadores web, compañías de desarrollo web y otro tipo de agentes que integraban el w c en esos momentos. durante este evento, profesionales de opera y mozilla realizan una presentación sobre la visión que tenían en aquellos momentos acerca del futuro de la web y qué se podía resumir en una premisa; «evolucionar el html existente en un estándar capaz de incluir nuevas características para los desarrolladores de aplicaciones web» (pilgrim ) además, subrayaron la importancia de su propuesta en torno a princi- pios (the mozzilla foundation & opera software ): . se puede consultar los detalles de este «workshop» en el siguiente enlace: http://www. w .org/ / /webapps-cdf-ws/ (accedido por última vez el / / ) http://www.w .org/ / /webapps-cdf-ws/ http://www.w .org/ / /webapps-cdf-ws/ raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd • backwards compatibility, clear migration path las tecnologías web que se utilicen, deben ser tecnologías, con las que los desarrolladores se encuentren familiarizados, como html, css, dom y javascript. por otro lado, las características a imple- mentar y las nuevas funcionalidades a soportar, deben ser en base a las que soporta el navegador internet explorer , ya que es el que mayor cuota de mercado tiene, y por lo tanto, a lo que la mayoría de los usuarios están acostumbrados. • well-defined error handling el manejo de los errores en las aplicaciones web debe ser definido a un detalle en el cual los desarrolladores no tengan que inventárselos o utilicen procesos de reingeniería basándose en cómo los maneja la competencia. • users should not be exposed to authoring errors las especificaciones deben especificar exactamente como se de- ben recuperar los errors, para cada escenario posible. • practical use cada nueva aplicación web que se genere, debe ser justificada por un uso práctico. (esto no tiene la misma validez en el caso contrario). • scripting is here to stay pero también debe evitarse, cuando pueda ser sustituido por el «len- guaje de marcas». • device-specific profiling should be avoided los desarrolladores deben ser capaces de implementar las mismas funcionalidades de la página, ya sea accedida a la versión de escri- torio o a través de un dispositivo móvil. • open process la web se ha beneficiado de su desarrollo en un entorno abierto. las aplicaciones web, serán de carácter primordial para la web y por lo tanto, su desarrollo deberá ser realizado de una manera abierta (listas de correo, drafts, etc). aparte de esta presentación y propuesta, también sondearon la opinión de los asistentes mediante una encuesta, en la cual ian hickson, de ope- ra software, preguntaba: «should the w c develop declarative extension to html and css and imperative extensions to dom, to address medium level raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd web application requirements, as opposed to sophisticated, fully-fledged os-level apis?» la votación fue de votos en contra y a favor. además de esta negativa, el w c hizo una declaración formal en la que indicaba que no iba a prestar apoyo ni ofrecer recursos a ninguna propuesta de desarrollo que no estuviera dentro de los grupos de trabajo que tenía establecidos en esa época (pilgrim ). debido a esta negativa del w c, el grupo de personas que habían hecho esta propuesta decidieron continuar su camino fuera del paraguas del w c. por ello, registraron el dominio whatwg.org y comen- zaron a trabajar en su propuesta, fundando el what working group (web hypertext applications technology working group) . este grupo de trabajo no oficial y abierto a la colaboración de terceros, se caracterizaba por estar formado por fabricantes de navegadores y agentes interesados que querían volver a los orígenes de html y no ahondar en lenguajes nuevos (como xht- ml). su enfoque se basaba en garantizar la compatibilidad regresiva o retro- compatibilidad , del nuevo estándar. una característica muy apreciada entre los usuarios y desarrolladores de lenguajes de programación y que sin duda contribuye a la coherencia de las trayectorias del desarrollo tecnológico. sin embargo, el w c quería proseguir con el desarrollo de xhtml, el cual no tiene compatibilidad regresiva con html. necesita de un «mime type» nue- vo y suponía tirar por la borda todo el trabajo realizado anteriormente con html. los navegadores siempre se «han olvidado» de los errores sintácticos de html y nadie se había preocupado hasta entonces, por como especifi- carlos. la historia del desarrollo web hasta este momento, se había basado en buena parte, en como los diferentes desarrolladores de navegadores ha- cían compatibles sus productos, con los de los competidores, ignorando las especificaciones y estándares. la mayoría de los navegadores se centraban en «poder presentar», de la mejor manera posible, «las sopas de etiquetas» que se creaban (andersson ). el what working group dedicó años de trabajo para documentar adecuadamente como analizar y diseccionar . se puede consultar la web que alojó este grupo de «insurrectos» y su declaración de intenciones en este enlace; http://www.whatwg.org/news/start . traducido del inglés; «backwards compatibility» . los mime types (multipurpose internet mail extensions) constituyen la especificación del tipo de documento que se intercambia. se señala en el comienzo del código de las páginas web. se puede ampliar la información respecto al concepto en sí en la página en castellano de la wikipedia. http://es.wikipedia.org/wiki/multipurpose_internet_mail_extensions http://www.whatwg.org/news/start http://es.wikipedia.org/wiki/multipurpose_internet_mail_extensions raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd html, de un modo compatible con las páginas existentes (pilgrim ). aparte de esta ingente tarea, este grupo también trabajó en el soporte nativo de audio y video (sin plugins), la nueva etiqueta «canvas» (que permite «di- bujar» directamente sobre la estructura del documento) y otra especificación en torno a aplicaciones web. el motivo de la fundación de este grupo es la disconformidad respecto a la visión que tenía de los estándares el w c. para el whatwg, el enfoque que hacía el w c era demasiado académico y por ello, la creación de este grupo aspiraba a la creación de una nueva versión del estándar, pero desde un punto de vista eminentemente práctico. el w c sin embargo parecía estar buscando en diferentes tecnologías un sustituto a html y especialmente se fijaba en xhtml . (o´mara ). lo cierto es que después de unos dos años y medio después de esa conferencia y los dos caminos separados que tomaron el w c y el wahtwg, estaba claro que xhtml languidecía mientras las nuevas características de html levantaban grandes expectativas. este hecho, se unía a las voces críti- cas que acusaban al w c de un avance lento y pocos resultados concretos (castro ). por eso, en octubre de , tim berners-lee y el w c anun- ciaron que trabajarían junto al wahtwg para añadir nuevas funcionalidades y evolucionar de manera conjunta xhtml. (berners-lee ) posteriormente, en octubre del , el w c cerraría el grupo de trabajo en torno a xhtml (le hegaret ) y pararía completamente sus activida- des en este lenguaje, para volcarse de lleno en el desarrollo de html , del cual se publicaría en un «working draft»(hickson and hyatt ), gra- cias a la unión de esfuerzos de las organizaciones. en los años siguientes, los navegadores comienzan a soportar html (mozilla firefox es el primero en dar el paso) y se empieza una fase de divulgación, difusión y conciencia- ción en torno a esta tecnología. sin embargo, el mayor impacto (desde el punto de vista de difusión social), se produce cuando steve jobs publica «thoughts on flash», haciéndose eco del mayor peso de los dispositivos móviles a la hora de desarrollar estándares y del problema que genera soft- ware propietario como «flash». steve elogiaba a html , css y javascript por su funcionalidad y por el hecho de constituir estándares abiertos (jobs ). otras compañías y plataformas con gran poder de prescripción social como youtube (harding ), slideshare (slideshare-blog ) y scribd . este documento de referencia sigue actualizándose y puede consultarse en el siguien- te enlace http://www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html http://www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd (calore ) también mostraron su apoyo a html y su intención de imple- mentar esta tecnología en sus aplicaciones, en la medida en que satisficiera sus necesidades de mercado. desde entonces y hasta ahora, el desarrollo de html ha seguido de manera imparable su curso. actualmente html es una «w c candidate recommendation», (w c ) con la vista puesta en , para alcanzar un estándar definitivo. . . las mejoras de html lo primero que debemos especificar en torno a html , es que no es una tecnología, sino un conjunto de tecnologías. esto es importante, ya que has- ta ahora, junto al protocolo http (hypertext transfer protocol) y al identifica- dor uri (universal reference identificator), html formaba un trío de tecnolo- gías clave para la world wide web. a partir de ahora, el paradigma de html engloba una serie de tecnologías que se recogen bajo un mismo estándar, pero que multiplican en gran medida las posibilidades del desarrollo web. y es que dentro de este estándar, van a tener cabida multitud de elementos dinámicos y multimedia, en forma de «etiquetas», que reconfiguran el en- torno web y los contenidos, tal y como los conocíamos. la especificación de html no se compone de una sintaxis únicamente, sino que admite dos sintaxis; html y xhtml (extensible hypertext markup language). así, los de- sarrolladores web pueden elegir entre un enfoque práctico, pero poco rigu- roso (html) o un enfoque académico y estricto (xhtml). el w c ha aceptado que html y xhtml sean recomendaciones paralelas que puedan coexistir (franganillo ). html no está basado en sgml (standard generalized markup language) y está diseñado para que tenga compatibilidad regresiva tanto con html como con xhtml (chau ). además de estructurar los documentos, html también aporta una gran mejora, que no es otra que la de cómo se deben interpretar los errores y poner fin de paso a la «guerra entre navegadores» que existía, para cómo se deben subsanar los errores. (andersson ; keith ) html presenta nuevos elementos (o etiquetas) destinados a ordenar y enriquecer la presentación de los documentos. son muestra de ello ele- mentos de carácter semántico como article, header, hrgroup, nav, section, raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd aside y footer. los blogs y web´s de noticias han influido en gran medida en la conceptualización de estos nuevos elementos (schafer ), ya que han introducido dinamismo en las web´s y sus contenidos y la necesidad de una cronología, para poder organizar la información. en particular, el elemento article, es uno de los que el w c ha introducido, para recoger más informa- ción sobre la página y está diseñado en base a los posts de un blog (w c ). en cuanto a la recogida de información, el medio típico a través del cual un usuario envía datos a un servidor es a través de los formularios. Éstos recogen la información que introducen los usuarios y la envían a aplicaciones que se ejecutan en el servidor. html incorpora un gran número de controles como email, range, date, time, placeholder, autofocus, etc, que ejercen su función sin necesidad de utilizar javascript. un lenguaje de programación que se ejecuta a través de un software que no tienen porqué tener instalado los usuarios de la web (pilgrim ). gracias a estas mejoras, html hace posible que sean los navegadores quienes faciliten la entrada y validación de datos, que tienen un patrón regular o están sometidos a restricciones. (franganillo ) este laborioso trabajo, ahora se descarga sobre los nave- gadores, en vez de sobre los diseñadores. aparte de estos elementos de estructura del lenguaje, los aspectos más innovadores de la sintaxis de html son sin duda, sus elementos dinámicos y multimedia. muchos de ellos han sido creados tras agrias polémicas y la li- beración de «códecs» en formato propietario (linder ; schonfeld ). hay que especificar también que aunque html no sea soportado por los viejos navegadores, esto no tiene importancia, ya que html no es técni- camente un lenguaje nuevo, sino una colección de nuevos elementos que pueden ser soportados por los nuevos navegadores (pilgrim ). html propone una nueva forma de estructurar la información de las páginas web, pero manteniendo la compatibilidad regresiva (tan importante en el desarro- llo de estándares). pero no sólo eso, ya que además provee de nuevas api´s (application programation interface), para reforzar la experiencia de usuario, pero sin la introducción de elementos procedentes de software propietario, sino fomentando la estandarización. algunos de los elementos más reseña- . api, del inglés «application programation interface», es una interfaz de programación de aplicaciones que permite interactuar a un software con otro, gracias a un conjunto de fun- ciones y procedimientos que se ofrecen a través de una biblioteca de recursos. raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd bles e innovadores de esta nueva versión de html son las etiquetas audio, video, canvas o geolocation, entre otras muchos. además de los elementos dinámicos que introduce html en su sintaxis, también hay otros dos len- guajes que complementan el espectro de este conjunto de innovaciones. por ello, no se puede entender html sin css (cascading style sheets); ya que es el lenguaje que regula los aspectos de estilo de las páginas web; y tampoco sin javascript; ya que este último permite programar acciones dinámicas y facilitar la interacción con el usuario. por último, también se ha lanzado una nueva versión del dom (document object model), que consiste en la colección de objetos que representan los elementos del lenguaje html en la página web. . la creación de html desde un punto de vista social el proceso que da origen al desarrollo de html es un caso de estudio en sí mismo por la idiosincrasia del mismo. muchas veces se ha incidido en el hecho de que la industria de los distribuidores de navegadores no han respetado las normas en cuanto a los procesos de estandarización y han promovido innovaciones que han generado muchos problemas, de cara a la normalización de los lenguajes implicados . pero en este caso, el «boicot» que lideran los integrantes de compañías como opera, mozilla y apple, se debe a que precisamente es el w c (que es la organización que vela por el desarrollo de los estándares), la que no decide apostar por una nueva ver- sión de html. por ello, las personas de estas compañías involucradas lideran el movimiento whatwg, para apostar por una nueva versión de html que incorpore elementos dinámicos y las api´s tan necesarias a su vez para crear las nuevos tipos de página web y aplicaciones que habían sido populariza- dos al albor del fenómeno conocido como «web . ». . uno de los episodios más memorables que nos deja la historia de la web, es el cono- cido como «la guerra de navegadores». en él, las dos compañías que pujaban por el dominio del mercado de los navegadores web (microsoft y netscape communications), se enzarzaron en una carrera tecnológica por ofrecer el máximo de funcionalidades y características al usuario final. este proceso conllevo la implementación de muchas funcionalidades en ambos navegado- res sin el proceso de contraste y aprobación necesario para la estandarización de las mismas. un buen ejemplo de esto es la extinta etiqueta «marquee». se puede ampliar la información al respecto en la página que la wikipedia en inglés dedica a esta cuestión http://en.wikipedia.org/ wiki/browser_wars http://en.wikipedia.org/wiki/browser_wars http://en.wikipedia.org/wiki/browser_wars raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd si bien hasta ahora hemos observado con detenimiento el desarrollo de html desde un punto de vista histórico y descriptivo. en este apartado, el objetivo es analizar, el proceso anteriormente descrito desde un punto de vista social y comprobar cómo los usuarios han jugado un papel deter- minante en el desarrollo del nuevo estándar. para ello se han establecido tres epígrafes en los cuales se abordan tres enfoques relacionados con la sistemática del proceso innovador que se ha estudiado previamente y en el cual se ponen de relieve las diferentes conceptualizaciones sociales de la tecnología implicada. el ánimo aquí, es cubrir la mayor parte de variantes de lo que se entiende como un sistema técnico y sus diferentes grupos de usuarios implicados en su conceptualización, desarrollo, mantenimiento y re-conceptualización. . . difusión e innovación social en html la difusión social de las innovaciones es un elemento clave en su po- pularización y adopción social. uno de los primeros autores en investigar el fenómeno de la difusión social de la innovación fue el sociólogo rural britá- nico everett rogers, el cual publicó en el libro titulado; «diffusion of innovations», en el cual definía el proceso de difusión social como; «difusión es el proceso mediante el cual una innovación es comunicada a miembros de un sistema social a través de ciertos canales a lo largo del tiempo» (rogers ) el caso de html , no ha sido diferente a esta lógica, ya que se han he- cho múltiples esfuerzos en varios canales, con el fin de divulgar las ventajas de este nuevo paradigma innovador. la difusión social de html ha sido un proceso en el cual han estado involucrados tanto instituciones como el w c, compañías privadas como apple y google, fundaciones sin ánimo de lucro como mozilla y personalidades de la talla de tim berners-lee (berners-lee ). todos ellos han maniobrado en una misma dirección, con el fin de que el cambio de paradigma innovador que suponía html , llegase a buen puerto. si esta innovación no hubiese sido aceptada y adoptada, es de su- poner que no hubiera tenido éxito (echeverría ), ya que una innovación sin difusión, no tiene ningún impacto económico (oecd ) y por lo tanto raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd no se populariza. así mismo, una percepción pública negativa, también pue- de ser una barrera infranqueable para esa innovación (lópez cerezo and gonzález ). por ello, una vez que el w c accedió a colaborar en el desarrollo de html , ha hecho mucho hincapié en la difusión de este nue- vo paradigma innovador. prueba de ello, son las campañas de marketing desarrolladas por el w c, enfocadas en la difusión del estándar y que han contado con el desarrollo de logos específicos de html , css y javascript (figura ). quizás, una de las figuras públicas que más apoyo han prestado en este sentido, ha sido el malogrado steve jobs, con sus declaraciones a favor del nuevo estándar y en contra del software propietario como flash (jobs ). en una decisión bastante polémica, llevó incluso este apoyo hasta las últimas consecuencias, denegando el soporte a flash, en su dis- positivos móviles como iphone, ipad e ipod. figura . logotipos de html , javascript y css por otro lado, también creemos que el proceso de creación de html constituye una innovación social en tanto que se cuestiona el «status quo» en cuanto a lo que estándares se refiere, se pone en entredicho al w c y se promueve un proceso participativo para apoyar el desarrollo de una nueva versión de html de acuerdo a unos principios y valores abiertos y comunes. una innovación social es relevante en la medida que se oriente a valores so- ciales (echeverría ) y el proceso por el cual se genera html responde a principios que salvaguardan tanto esos valores sociales, como una co- herencia con el desarrollo tecnológico desarrollado hasta la fecha. creemos que el proceso de creación de html no se limita a un proceso de desarrollo raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd tecnológico al uso, sino que hay una compilación de saberes explícitos e implícitos que se mezclan con las innovaciones técnicas (innerarity and gur- rutxaga ) que se desarrollan en este periodo de tiempo. la creación de html no pasa por la identificación de un problema nuevo, sino por la redefinición de un problema existente, al cual no se había enfrentado desde un marco conceptual adecuado, tal y como hemos expuesto anteriormente. este sentido de innovación social que queremos recoger aquí, se aleja un poco del que promulga geoff mulgan (mulgan et al. ; mulgan ), en el sentido de que las organizaciones que promueven este cambio no tienen fines sociales . no es nuestro objetivo aquí fijarnos en el tipo de agente que promueven estas innovaciones, sino reconocer y analizar el proceso que se genera. por ello, creemos que la creación de html abre la puerta a un nuevo paradigma de la innovación y es un movimiento que se genera desde abajo hacia arriba, volviendo a los propios valores que generaron la web. además, html asienta las bases para crear nuevas innovaciones en torno a unos principios sociales y tecnológicos que deben ser consensuados y res- petados, para garantizar la cohesión y el desarrollo tecnológico sostenible. . . ¿construcción social o tecnología autónoma? al revisar el proceso de conceptualización y desarrollo de html , llama poderosamente también la atención, la cantidad de actores implicados en su desarrollo, el número de lenguajes de programación, marcado y diseño (y por lo tanto, itinerarios tecnológicos a tomar) y las diversas interacciones que se producen entre estos agentes y las posibles trayectorias tecnológicas. por ello, a la hora de recoger los fragmentos que la historia tecnológica de este desarrollo nos ha dejado por el camino, no es fácil elegir una metodolo- gía o un marco de actuación que nos empodere totalmente de cara a realizar una «foto» lo más precisa posible de todos estos hechos. este es un tema que se ha repetido a lo largo de la historia de los estudios sociales de cien- cia y tecnología, y en el cual ha habido varias escuelas y corrientes que han intentado dar su propia explicación de la dinámica del cambio tecnológico . apple y opera son compañías privadas. por otro lado, mozilla foundation es una conocida fundación sin ánimo de lucro que tiene como misión «mantener la elección y la inno- vación en internet». raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd (hackett et al. ). durante muchas décadas, los estudios del desarrollo tecnológico han interpretado la tecnología en un sentido mucho más amplio que el que puede referirse a un artefacto o una herramienta en particular. esta búsqueda por encontrar una definición los más completa posible ha generado una gran cantidad de literatura al respecto y ha expandido nuestra percepción utilitarista y artefactual de la tecnología (gonzález garcía, lópez cerezo y luján ). entre otros autores que han promovido una compren- sión más holística de lo que significa el concepto de técnica y tecnología, nos gustaría mencionar a jacques ellul (ellul ) y miguel Ángel quintanilla (m. Á. quintanilla ). estos dos autores han introducido en sus dos definicio- nes de técnica, el concepto de eficiencia, el cual se convierte en uno de los resortes de la dinámica social. los autores anteriormente mencionados, nos sirven de introducción al modelo scot ( social construction of technology).el cual también es co- nocido como «constructivismo social» y que contempla a los usuarios de la tecnología como un grupo social que juega un papel fundamental en el desarrollo de las tecnologías involucradas (bijker, hughes, and pinch ). este modelo desarrollado por bjiker, hughes y pinch, supuso un punto de inflexión en los estudios sts (science, technology and society), a la hora de explicar la dinámica y caracterización del desarrollo tecnológico. en este enfoque, la idea de «sistema tecnológico» juega un papel muy importante, a la hora de comprender la dimensión social de la tecnología (hughes ). la idea de «sistema tecnológico» es bastante similar a la que quintanilla de- nomina como «sistema técnico», la cual describe como: un dispositivo complejo compuesto de entidades físicas y de agentes hu- manos, cuya función es transformar algún tipo de cosas para obtener de- terminados resultados característicos del sistema. (m. a. quintanilla ) bijker también ahonda en el concepto de tecnología y establece a su vez, tres capas diferentes de significado: artefactos físicos, actividades humanas y conocimiento. (bijker ) en estas concepciones de técnica, tecnología, sistema técnico y sistema tecnológico, residen no sólo artefactos, sino también sujetos sociales, siste- mas sociales y diversos tipos de conocimientos. queremos hacer hincapié en este «sentido social» que tiene el desarrollo de la tecnología, ya que el raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd caso que nos ocupa del desarrollo del nuevo estándar html , creemos que encaja perfectamente bajo este marco teórico. el desarrollo del estándar no se lleva a cabo por un modelo de desarrollo tecnológico o de «innovación lineal» (lundvall ), sino que es fruto de un proceso iterativo en el cuál hay una retroalimentación de diversos actores y paradigmas tecnológicos diversos. la construcción de este nuevo estándar creemos que es un pro- ceso social, en el cual hay varios agentes implicados en su creación y desa- rrollo, en mayor o menor medida. como ya hemos señalado previamente, el w c es la organización que gestiona el desarrollo de estándares para la web, pero debido al estancamiento de sus propuestas en torno a xhtml y su difícil encaje, fueron perdiendo fuelle, a favor de la nueva propuesta que hicieron las personas implicadas de las organizaciones opera software, the mozilla foundation y apple. en el modelo scot se enfatiza que la tecnología no determina el curso de la acción humana, sino más bien al contrario. la forma final de un artefacto tecnológico es el resultado de un proceso social, en el que diversos grupos sociales juegan un papel crucial en la selección de las variantes a elegir (bijker and pinch ), posibilitando la supervi- vencia de unas trayectorias y la extinción de otras. este proceso es al que bijker y pinch enuncian como la «flexibilidad interpretativa» de la tecnología (bijker, hughes, and pinch ; bijker and pinch ). diferentes grupos de usuarios pueden construir diferentes significados para con la tecnología, pero a medida que el paradigma dominante se abre paso, los demás signi- ficados se desvanecen. por ello, entender el papel que juegan estos grupos de usuarios es clave. en el caso que nos ocupa, el grupo de usuarios que formaron los desarrolladores de firefox, opera y apple, es decisivo en el establecimiento del paradigma dominante en el desarrollo de html y de los valores que hay detrás de este nuevo paradigma tecnológico. este último punto nos lleva irremediablemente a tener que hablar de la relación de las tecnologías y los valores, un tema que toma forma expresa en un famoso artículo de langdon winner, titulado «do artifacts have politics?» (winner ). también, es el propio winner quien realiza una influente crí- tica del modelo scot, por lo descriptivo y analítico del mismo y por lo poco crítico del modelo, respecto al desarrollo tecnológico (winner ). por ello, a pesar de que el modelo scot es de gran ayuda para describir la dinámica del desarrollo tecnológico (como el propio winner admite) y explicar cómo es construida socialmente la tecnología, debemos también hacer mención al concepto de «tecnología autónoma» (winner ), ya que la historia de raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd html es una reacción en cierto modo a la situación «fuera de control» que se produce en el desarrollo de estándares debido al fenómeno «web . ». tal y como define winner, la idea de tecnología autónoma; «sirve de etiqueta a todas las concepciones y observaciones en el sentido de que la tecnología escapa de algún modo al control humano» (winner : ). como argumenta winner, ciertas técnicas son capaces de desencadenar efectos no previstos o deseados. esto es a lo que él se refiere como una peculiaridad de la tecnología del siglo xx, en el sentido de la pérdida del dominio (sobre la tecnología) se manifiesta en una mengua en nuestra habilidad para conocer, juzgar o controlar nuestros medios técnicos. (winner : ) lo cierto es que la corta, pero intensa historia de la web está llena de episodios en los cuales, el desarrollo de estándares es siempre uno de los mayores perjudicados. esta pérdida del dominio tecnológico viene represen- tada por varios factores que se dan en el desarrollo de la web, por motivos muy diversos, intereses encontrados y agentes dispares. ejemplo de esta pérdida del dominio tecnológico es la proliferación de software propietario como flash, a lo largo del periodo conocido como «web . » y que cons- tituyen una gran amenaza a la interoperabilidad de la plataforma que en su día ideó tim berners-lee. otros episodios anteriores a este periodo de po- pularización de la web, como la famosa «guerra de navegadores» también ha dejado anécdotas cuando menos inquietantes como la proliferación de elementos extraños en el desarrollo de estándares como la etiqueta mar- quee (una etiqueta que hacía que el texto «bailara por la pantalla»). este tipo de desarrollos, mejoras e innovaciones son una de las principales ar- mas que utilizan los distribuidores de software y navegadores web, para presionar e ir «más allá de los estándares». la justificación de este énfasis por la mejora continua de las aplicaciones, es debido a que si dichas nuevas . las etiquetas marquee (ie) y blink (netscape) son dos ejemplos de cómo a veces el empuje de las compañías por innovar y ofrecer algo diferente al usuario puede convertirse en algo problemático que eche por tierra el trabajo ya realizado. estas etiquetas se caracterizan por ofrecer textos que continuamente se mueven en la pantalla. lo cual suponía un auténtico quebradero de cabeza para los usuarios que querían consultar información, sin constantemente tener distracciones en la pantalla. además, también presentaban bastantes problemas en la optimización del código. se puede consultar en la página de la wikipedia en inglés esta informa- ción. http://en.wikipedia.org/wiki/marquee_element [consultado el / / ] http://en.wikipedia.org/wiki/marquee_element raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd funcionalidades son aceptadas y valoradas por una mayoría de usuarios de la web, suelen traducirse en una mayor cuota de mercado. por ello, la ma- yoría de compañías que basan su modelo de negocio en la web presionan en esta dirección. el papel del w c siempre ha sido el de velar por el que to- dos estos «empujes», no atenten contra la naturaleza de la web e internet y controlar la incorporación de elementos externos o propietarios al estándar. . . el poder de los usuarios por último, en esta visión social del fenómeno html nos gustaría pres- tar atención a un último grupo, cuyo papel puede haber sido determinante en todo este proceso; los usuarios. si bien hemos constatado como a través de una serie de agentes se promueve un cambio a favor de la re-estandari- zación de la web y el abandono de elementos externos o de software pro- pietario, creemos que una de las mayores fuerzas de cambio que posee la world wide web son sus propios usuarios. durante el fenómeno conocido como web . , el cual abarca un periodo de tiempo en torno a finales de lo ´ hasta finales de la siguiente década (es difícil cuantificar cuando se acaba esta época, ya que es un concepto difuso y en permanente evolución), se produce un gran incremento de usuarios de la web, debido en su mayor par- te a la popularización de la misma, a través de la aparición de aplicaciones colaborativas (y que posteriormente se catalogarían como medios sociales). esta popularización de la web a través de este tipo de aplicaciones es uno de sus mayores puntos de inflexión, ya que contribuye en gran medida a su popularización. el creador de la web, tim berners-lee ha mostrado y manifestado en varias ocasiones su contrariedad a que la «primera versión» de la web no tuviera esa «centralidad» en las personas (laningham ). pero lo cierto es que en sus primeras etapas, la web es percibida como un medio en el cual solo podían publicar contenidos un reducido número de personas , con los conocimientos necesarios (p. anderson ) y es . quizás, el origen del problema pueda estar en el propio desarrollo tecnológico inicial de la web y en los primeros navegadores que se desarrollan; violawww, mosaic y netscape, los cuales no traen integrada por defecto, una función de «editar» (netscape en sus últimas versiones sí que implementaría de forma opcional un editor de html). raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd innegable que hasta el desarrollo de la web . no se percibe ésta como un producto de masas (duggan and smith ). figura . horas de vídeo subidas a youtube desde junio de a mayo de fuente: kpcb a través de youtube. además de atraer usuarios, la web . también produce un gran cam- bio, en el tipo de contenidos que se producen en la misma, ya que a partir de este momento el multimedia (fotos, videos, etc.) pasa a cobrar un mayor pro- tagonismo. los usuarios que no disponen de los conocimientos necesarios a nivel de programación (html, css, javasscript, php, etc.), ven en plata- formas como facebook, blogger, youtube o flickr, la herramienta ideal que se adapta a sus necesidades y con la cual pueden compartir información e interactuar con otros usuarios. las «tecnologías sociales» (helmer, brown, and gordon ) que aparecen en este periodo constituyen la «caja de herramientas» que necesitaba el usuario no técnico para poder generar con- tenido e interactuar con otros usuarios, intercambiando información. este tipo de procesos capacitadores, de cara a los usuarios, es lo que algunos autores han identificado como una «democratización de la innovación» (von hippel ). raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd en nuestra opinión, estos primeros usuarios de este tipo de aplicaciones o «lead users» (von hippel ) son los principales causantes de la popu- larización de la web. la generalización de este tipo de servicios, de cara a crear y compartir contenidos, unidos a otras fuerzas como el «efecto red» (klemperer , liebowitz and margolis ; shapiro and varian ), «la economía de la larga cola» (c. anderson ; c. anderson ), el fo- mento de una «arquitectura de participación» (o´reilly ) e incluso la con- solidación en la web de «tecnologías fáticas» (wang, tucker, and rihll ; tucker, wang, and haines ) producen el ecosistema idóneo para que los usuarios no técnicos , puedan crear y compartir fácilmente información en la world wide web. a partir de la eclosión del fenómeno conocido como «web . » se rebajan las barreras de entradas de uso de las aplicaciones, promoviendo la sencillez en su uso, entornos más ligeros (que no consuman mucho ancho de banda) y que demuestren su interoperabilidad a través de api´s (muchas veces explotando datos de los servicios, con el objetivo de que terceros puedan desarrollar «mash-up´s» [p. anderson ]). figura . crecimiento de usuarios de internet desde fuente: wikipedia. . entendemos como usuario no técnico, aquel que no dispone de conocimientos de programación web. es decir, ausencia de conocimientos de lenguajes como html, css, javas- cript, php, pearl, python, etc. . un «mash-up» es una aplicación web, que se sirve de otras fuentes (a través de una api) para crear un servicio de agregación o de valor añadido. el sitio web http://digg.com/ es un ejemplo de «mash-up». http://digg.com/ raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd este nuevo ecosistema, hace posible que los usuarios también puedan editar la web (aunque no directamente) y de este modo empezar a innovar en ella. el «social media» o «medios sociales» se convierte en la herramienta del usuario para poder crear y compartir contenidos, pero además, también es el elemento con el cual se influye en el desarrollo tecnológico. esto es debido a que una mayor predominancia de elementos multimedia, hacen necesarios un mayor conjunto de elementos nativos de estandarización, ya que si se abusa de software propietario, se ralentiza la experiencia de usuario y la interoperabilidad entre servicios. también podemos decir, que al fin y al cabo, son los clásicos criterios de eficiencia de un sistema técnico, los que residen en esta argumentación (ellul ; m. Á. quintanilla ). otros autores han definido este tipo de influencia también como «cultura», en el sentido de que sobrepasa las preferencias individuales e influye en el desa- rrollo tecnológico (castells ) por otro lado, el peso de los usuarios también se nota directamente en el desarrollo puramente técnico del estándar, ya que como el propio w c describe, el elemento article está diseñado en base a los posts de un blog (w c ) y los propios blogs han influido en gran medida en la conceptu- alización de nuevos elementos (schafer ) presentes en html . . conclusiones en el presente artículo hemos explorado el proceso de creación y de- sarrollo de html tanto desde la perspectiva tecnológica, como desde la perspectiva social. el objetivo ha sido siempre el de proporcionar visiones complementarias, con el fin de diseccionar las interrelaciones que se produ- cen entre estas dos perspectivas. tal y como hemos presentado, en el desarrollo de html existen ele- mentos característicos del modelo scot y el «constructivismo social», pero al mismo tiempo, algunos de los efectos no deseados de la «tecnología autónoma». en contraposición a esta dualidad, también hemos explorado el papel de los usuarios en el proceso de creación del nuevo estándar y espe- cialmente su influencia oculta, en la conceptualización del nuevo estándar y del paradigma de innovación que rige el desarrollo de los estándares web. raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd en nuestro trabajo, sugerimos que los usuarios no técnicos han influido decisivamente, a través de la adopción y uso de medios sociales o «social media» en a) la popularización y apropiación social de la world wide web. b) la vuelta a la estandarización y el abandono de software propietario, a favor de html . c) la primacía de contenidos multimedia en la world wide web. como hemos descrito anteriormente, si bien esta influencia no se pro- duce de manera directa (ya que los usuarios no editan directamente la web) y la cantidad y complejidad de las relaciones entre actores hace difícil de- finir una interdependencia clara entre factores. creemos no obstante, que el número de usuarios y su preferencia por crear y compartir determina- dos tipos de contenidos, son una de las palancas de cambio que ejercen influencia a la hora de que los desarrolladores, distribuidores de software, instituciones y demás agentes implicados, apuesten por un desarrollo tec- nológico que prime la eficiencia, la interoperabilidad, el acceso distribuido y la retro-compatibilidad. por todo ello, creemos que nuestra investigación contribuye a aportar mayor profusión y entendimiento de la importancia del usuario en el desa- rrollo tecnológico de la world wide web, y en especial del desarrollo del estándar html. en este sentido, también pensamos que se abre un nuevo horizonte para los estudios sociales de ciencia y tecnología, a la hora de considerar el papel del usuario y su influencia en este tipo de desarrollos tecnológicos. . bibliografía anderson, chris ( ): the long tail. wired. http://www.wired.com/wired/archi- ve/ . /tail.html. anderson, chris ( ) la economía «long tail». de los mercados de masas al triunfo de lo minoritario. barcelona. ediciones urano. anderson, paul ( ): what is web . ? ideas, technologies and implications for education http://www.jisc.ac.uk/media/documents/techwatch/tsw b.pdf. andersson, david ( ): html , xhtml , and the future of the web. http://www. digital-web.com/articles/html _xhtml _and_the_future_of_the_web. raúl tabarés gutiérrez la belleza del código. el desarrollo de html artefactos, vol. , n.º , diciembre , - / cc by-nc-nd berners-lee, tim ( ): reinventing html. http://dig.csail.mit.edu/breadcrumbs/ node/ . bijker, wiebe e. 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. la creación de html desde un punto de vista social . . difusión e innovación social en html . . ¿construcción social o tecnología autónoma? . . el poder de los usuarios . conclusiones . bibliografía beauty, weight, and skin color in charitable giving journal of economic behavior & organization ( ) – contents lists available at sciencedirect journal of economic behavior & organization j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j e b o beauty, weight, and skin color in charitable giving� christina jenq a, jessica pan b, walter theseira c,∗ a hong kong university of science and technology, hong kong b national university of singapore, singapore c unisim college, sim university, singapore a r t i c l e i n f o article history: received april received in revised form june accepted june available online july jel classification: d o keywords: charitable giving microfinance lending statistical discrimination implicit bias peer-to-peer lending a b s t r a c t this paper examines bias in online charitable microfinance lending. we find that charitable lenders on a large peer-to-peer online microfinance website appear to favor more attractive, lighter-skinned, and less obese borrowers. borrowers who appear more needy, honest and creditworthy also receive funding more quickly. these effects are quantitatively significant: borrowers with beauty one standard deviation above average are treated as though they are requesting approximately % less money. statistical discrimination does not appear to explain our findings, as these borrower attributes are uncorrelated with loan performance or borrower enterprise performance. the evidence suggests implicit bias could explain our findings: more experienced lenders, who may rely less on implicit attitudes, appear to exhibit less bias than inexperienced lenders. © the authors. published by elsevier b.v. this is an open access article under the cc by license (http://creativecommons.org/licenses/by/ . /). . introduction a large literature in economics examines discrimination in a variety of market settings. much of the literature has focused on discrimination on the basis of demographic attributes such as race, ethnicity and gender. more recently, studies have found a link between beauty and the labor market (hamermesh and biddle, ; biddle and hamermesh, ; mobius and rosenblat, ) and credit access (ravina, ). while such evidence of discrimination has been robustly documented in market settings, it remains an open question as to whether discrimination plays a role in non-market settings such as charitable giving. in this study, we investigate whether systematic lender biases on the basis of beauty, weight and skin color play a role in charitable decision-making. we examine discrimination in a new setting – direct philanthropy on kiva.org, an online peer-to-peer microfinance website. we show that discrimination in direct philanthropy exists, and we argue that � we thank participants at the second european research conference on microfinance, australasian meeting of the econometric society, singapore economic review conference, and asian meeting of the econometric society for helpful comments. jonathan heller generously provided part of the data and joanne pan provided excellent research assistance. portions of this work were completed while walter theseira was affiliated with nanyang technological university, singapore, and while christina jenq was affiliated with the university of chicago booth school of business, usa. the authors gratefully acknowledge financial support from a national university of singapore start-up grant and from a nanyang technological university start-up grant. ∗ corresponding author at: unisim college, sim university, clementi road, singapore , singapore. tel.: + . e-mail address: walter.theseira@gmail.com (w. theseira). a number of other papers have utilized the kiva data; a short discussion is provided in the literature review. http://dx.doi.org/ . /j.jebo. . . - /© the authors. published by elsevier b.v. this is an open access article under the cc by license (http://creativecommons.org/ licenses/by/ . /). dx.doi.org/ . /j.jebo. . . http://www.sciencedirect.com/science/journal/ http://www.elsevier.com/locate/jebo http://crossmark.crossref.org/dialog/?doi= . /j.jebo. . . &domain=pdf http://creativecommons.org/licenses/by/ . / mailto:walter.theseira@gmail.com dx.doi.org/ . /j.jebo. . . http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / i i d r l f d a d o m u c h f g i p o c o o ( e a i t p p d m l g p a l a o a p t o c l i w c. jenq et al. / journal of economic behavior & organization ( ) – t is increasingly relevant given the rapid growth in online direct giving, and given the extent to which private giving is ncreasingly substituting for institutional giving, which may be driven by very different preferences. our study departs from much of the literature on discrimination and charitable giving by using large-scale observational ata of the decisions made by tens of thousands of actual charitable lenders, choosing over thousands of real charitable ecipients. previous studies have been based on experiments conducted on laboratory participants (andreoni and petrie, ), consumer research panels (fong and luttmer, ), and on households canvassed door-to-door (landry et al., ; ist and price, ). while participants in the literature are representative of the general population, they are different rom actual donors. in contrast with the literature, our paper examines how biases shape the intensive margin behavior of onors who give to international charitable causes. we examine how donor-perceived attractiveness, weight, skin color, nd other characteristics affect charitable giving decisions made on a large sample of charitable recipients drawn from many eveloping countries. we circumvent typical omitted variables concerns that plague most observational studies because ur data capture virtually all the information donors have access to. the online international development donors we study comprise a growing and influential share of the overall charitable arket. in the united kingdom, charities focusing on international development rank at the top of the income tables, taking p to two-fifths of all private giving in some years (atkinson et al., ). in aggregate, private giving from individual donors omprises % of the $ billion charitable giving market in the united states (giving usa, ). online giving in particular as grown more rapidly than traditional forms of giving in recent years (frostenson et al., ). online giving often departs rom traditional giving by allowing donors to give directly to a particular individual, group, or project, instead of having their iving distributed by a non-profit organization or government. the growth of online directed giving matters when the exhibited preferences or biases of individual donors differ signif- cantly from those of institutions and governments, and when such preferences have an impact on social outcomes. donor references and funding flows matter because microfinance institutions depend on donor subsidies, obtain a negative return n assets, and are generally not self-sufficient (cull et al., ). even the nobel-prize winning grameen bank depends on apital subsidies from donors and would have to raise interest rates charged substantially without such assistance (murdoch, ). this dependence on capital subsidies provides strong incentives for microfinance institutions (and other development riented institutions) to focus on projects or clients who suit the preferences of donors – even if those preferences are based n physical characteristics such as beauty or weight. our paper’s contribution is to document and interpret the causes of such exhibited individual donor preferences. as list ) points out, there is little evidence on how different types of agents pursue the same broad charitable goals. after the nd of the cold war, official development assistance from the major international donors and multilateral aid institutions ppears to have been channeled increasingly toward poorer, more democratic countries (dollar and levin, ). however, t is not clear that private individuals in those same donor countries share these preferences; desai and kharas ( ) show hat donations on kiva appear to favor relatively rich and less democratic countries instead. analyses that simply assume rivate and public sources of aid are substitutable in aggregate risk generating misleading conclusions if these differing references are not considered. kiva facilitates the transfer of funds from charitable lenders in developed countries to microfinance recipients in less eveloped countries. although kiva was only founded in , by february , it had facilitated the loan of almost $ illion us dollars, from nearly , individual donors, to more than , microfinance borrowers. kiva facilitates oans by working with local microfinance institutions (mfi) to screen potential borrowers. when a suitable borrower or roup of borrowers is identified, kiva works with the mfi to create a loan profile on the kiva internet platform. the loan rofile includes a picture of the borrower, a brief biography, loan purpose, loan amount and repayment schedule. the profiles lso provide detailed information on the partner mfi such as their risk rating, tenure with kiva, the number and volume of oans made and the delinquency rate of previous loans. potential lenders access loan profiles through the kiva website and choose entrepreneurs they wish to support. kiva ggregates the small loans provided by individual lenders to meet the loan amount requested by the borrower. lenders n kiva receive no interest on their loans, but are still subject to default risk and exchange rate risk. while borrowers re charged interest, this is retained by the local mfi and is not remitted to the kiva lender. kiva lenders are essentially roviding subsidized, interest-free loans to the partner mfis. although each loan has a low risk of default (about . % during he sample period), the majority of lenders make more than one loan. the average number of loans made by lenders in ur sample is (with a standard deviation of loans), suggesting that the average lender in our sample faces roughly a % chance of having at least one loan default. thus lenders forgo the use of their capital for the duration of the loan, bear redit risks, and in practice, often do not withdraw their funds from kiva even after loans are repaid. for these reasons, ender behavior has more in common with charitable giving than investing, and as such, we use the terms donor and lender nterchangeably. “directed” gifts may still be fungible if they relieve a charitable organization’s budget constraint with respect to unrestricted donations. according to matt flannery, kiva’s co-founder, “they (lenders) are just keeping the (repaid) money in their [kiva] account. maybe they didn’t know it as a loan. maybe they thought it was a donation.” (kiva: improving people’s lives, one small loan at a time. knowledge@wharton podcast, may th (kiva, ).) c. jenq et al. / journal of economic behavior & organization ( ) – the ‘direct-giving’ context on kiva means that our study captures the determinants of funding decisions from donors who are interested in making a specific impact with their gifts. such altruistic motivations are represented in atkinson’s ( ) ‘identification’ model, which assumes people give because they believe their gifts will have an impact on specific recipients or causes. we assume kiva lenders face two considerations. first, they care about the social impact of their loan, and should prefer borrowers that maximize social impact. second, lenders should care about enterprise profitability and risk, since recovery of the loan principal allows re-gifting of the loan. as virtually all loans on kiva eventually receive full funding, we analyze the speed with which loans are funded as a proxy for the relative attractiveness of a given loan. since kiva lenders often face more than a thousand different charitable loans to choose from, a loan that is funded more quickly should have a combination of attributes that lenders find more attractive. we start by examining how lenders respond to objective loan characteristics or ‘hard’ information such as loan amount, country of origin, mfi performance and mfi default risk in making funding decisions. next, we examine whether lenders’ decisions are also influenced by physical characteristics such as gender, attractiveness, weight and skin color. we also include ‘soft’ information such as perceived neediness, honesty and creditworthiness. our empirical analysis is a test for ‘disparate treatment’ of loan recipients, examining whether certain types of borrowers are treated differently holding constant other dimensions. we find that donors discriminate on the basis of attractiveness, weight and skin color. a one standard deviation increase in assessed attractiveness is associated with a reduction in time to full funding of approximately %, while a one standard deviation increase in assessed physique (more overweight) is associated with an increase in funding time of about %. the corresponding funding time increase for borrowers with skin color one standard deviation darker is about %. for comparison, a ten percent increase in the loan amount requested (approximately $ ) is associated with an increase in funding time of about %. therefore, borrowers who are one standard deviation more attractive (or more overweight, or darker-skinned) are treated by the market as though they were asking for $ less (or $ more, or $ more). these estimates are economically significant when compared to the average loan amount of about $ . these effects are robust to a wide range of controls including loan characteristics, country fixed effects, mfi fixed effects, economic sector and business activity fixed effects, and fixed effects for the date the loan is posted. we also find strong evidence that female borrowers are funded faster. we next investigate potential explanations for these patterns of discrimination. one hypothesis is that lenders statistically discriminate on observable borrower characteristics that are correlated with unobserved underlying productivity or default risk (phelps, ; arrow, ). although this is a charitable setting, donors may still care about default risk because a non-defaulting enterprise is likely to have greater social impact and preserves capital for other recipients. to evaluate this hypothesis, we examine data on the performance of the loan. the average default rate of all kiva loans is very low and our sample’s default rate is about . %. however, we find no evidence that borrower physical characteristics significantly predict loan default, once other material loan characteristics are controlled for. this is inconsistent with the hypothesis of lender statistical discrimination on the basis of default risk, which would predict that less-preferred borrower attributes are correlated with higher risk. nevertheless, lenders may also care about the overall profitability of the enterprise even if there is little risk of the loan defaulting. the beauty literature has long found an association between physical attractiveness, labor market outcomes (biddle and hamermesh, ; mobius and rosenblat, ), and productivity in customer-oriented positions (hamermesh and biddle, ; pfann et al., ). accordingly, we expect lenders to statistically discriminate on beauty more when the borrower belongs to an industry such as services or retail where business productivity depends highly on appearance, but less when the borrower is in an industry where appearance is less important, such as construction, manufacturing and transport, or agriculture. we find the attractiveness premium to be similar across all economic sectors. overall, our evidence is inconsistent with statistical discrimination, both on the basis of beauty-related productivity differentials and on physical characteristics predicting default risk. if our findings are not readily explained by statistical discrimination, what remains is a pattern of bias – explicit or implicit – that presumably reflects the preferences or attitudes of lenders. while economists have traditionally modeled taste-based discrimination as the result of conscious choices (becker, ), psychologists argue that discriminatory behavior may also as our dataset only covers the lending behavior of a sample of individuals on kiva, we do not examine why an individual gives at all, or why they choose kiva instead of alternative channels. nonetheless, the population of lenders on kiva is substantial, standing at nearly , lenders on kiva as of february , drawn from virtually every country worldwide. in atkinson ( ), donor beliefs need not be consistent with the reality that private small-scale donations are unlikely to have a measurable impact. what is important is that donors perceive they can make a difference in a particular recipient’s life through their giving. indeed, charitable causes generally emphasize this concept in their marketing even if the reality is a little different. although all projects on kiva are eventually funded, biases affecting time-to-funding still have welfare implications. other charitable websites which solicit individual donations are much less successful than kiva. for example, on globalgiving.org, which finances traditional development projects, typical times to full funding are in the order of months or more, although this may be attributable to kiva controlling funding requests more strictly (desai and kharas, ). donor biases can also be expected to influence how charitable agencies choose clients and projects, especially if they intend to use online appeals for funding. one explanation for this low rate is that mfis were allowed to cover entrepreneurs’ defaults in order to keep their published default rates low. while this practice is now forbidden by kiva, it was allowed throughout the period from to . see http://www.kiva.org/updates/kiva/ / / /update-on-recent-change-in-default.html. http://www.kiva.org/updates/kiva/ / / /update-on-recent-change-in-default.html http://www.kiva.org/updates/kiva/ / / /update-on-recent-change-in-default.html b l t i l k c w u a i o p p l k g s ( h l e f f n p m i t a c i c e l l c k r o a a t p c. jenq et al. / journal of economic behavior & organization ( ) – e driven by implicit attitudes and unconscious mental associations (baron and banaji, ). implicit attitudes are more ikely to influence behavior when decision makers face a high degree of information overload and ambiguity regarding heir choices (bertrand et al., ). the literature on choice overload finds that individuals faced with too many choices, n various settings, behave as though they are cognitively burdened and make qualitatively different decisions (iyengar and epper, ; iyengar and kamenica, ). we argue that implicit discrimination may characterize lending decisions on iva, because of the dizzying array of choices available and the lack of any obvious decision criteria for making a funding hoice. we provide two pieces of indirect evidence that appear consistent with this hypothesis – first, we show that lenders ith less experience on kiva are more likely to exhibit bias in funding loans. this is consistent with evidence from the widely sed implicit association test showing task experience significantly reduces implicit bias effect sizes (nosek et al., ), nd suggests implicit discrimination may explain part of our findings. second, we show that as demand for credit increases, nexperienced lenders are even more likely to exhibit bias in funding loans, consistent with the cognitive burden of choice verload leading to increased reliance on implicit attitudes. the rest of the paper proceeds as follows. the next section provides a literature review. section describes the data and rovides additional details about kiva. section discusses the effects of borrower attributes on loan funding times and loan erformance. section explores the relationship between lender experience and lender bias. section concludes. . literature review this paper adds to a recent, but growing literature that explores racial and beauty biases in charitable giving in the aboratory and in the field. fong and luttmer ( ) experimentally vary racial information in photographs of hurricane atrina victims shown to potential donors and find that respondents who report feeling close to their own racial or ethnic roup give substantially more when victims are of the same race. landry et al. ( ) find that more attractive women olicitors are able to secure more and larger donations in door-to-door fundraising experiments. similarly, list and price ) find that minority solicitors are less likely to obtain a contribution, whether approaching a majority or minority ousehold. in the laboratory setting, with public goods games, andreoni and petrie ( ) show that subjects are more ikely to cooperate in the presence of beautiful people even though more beautiful people are not actually more coop- rative. while these studies support the link between physical appearance and charitable decision-making, they largely ocus on laboratory subjects (andreoni and petrie, ) or use a small number of solicitors (landry et al., ) drawn rom american college students. our research question is also not directly addressed by the existing work on discrimi- ation in microfinance, which focuses on bias in credit allocation at the mfi level (agier and szafarz, ; labie et al., ). on a broader level, this paper is also closely related to a series of papers documenting discrimination in pros- er.com, a for-profit peer-to-peer online credit market in the united states. recent work shows that lenders in this arket appear to discriminate based on borrower attributes such as race and physical appearance (pope and snydor, ; ravina, ; theseira, ), raising concerns that this reliance on “soft information” might undermine the abil- ty of credit markets to allocate funds according to creditworthiness (iyer et al., ). the kiva market itself is also he subject of active study, with research on the determinants of funding decisions (ly and mason, ), how trans- ction costs and social distance affect funding decisions (meer and rigbi, ) and on how social identity affects haritable behavior (liu et al., ). however, we are not aware of significant prior evidence on whether and how nternational charitable donors discriminate on physical traits, in philanthropy directed at recipients in developing ountries. . data . . details on kiva.org kiva has been in operation since , with loans posted for funding since february . from through , kiva xperienced rapid growth in loans posted and dollars loaned, as shown in fig. . whilst in january , less than a thousand oans were posted monthly, by the end of , nearly eight thousand loans were posted each month, for an average monthly oan volume of $ million. the average amount requested per loan was $ and did not vary significantly during the period – . in february , kiva reported a total loan volume in excess of $ million dollars (since inception), and a lient base of more than , borrowers. kiva partners local microfinance institutions (mfis) in developing countries. to become a field partner, mfis have to meet iva’s minimum requirements and pass an on-site due diligence where kiva personnel assess the stability, governance and isk profile of each mfi. based on the mfi’s tenure with kiva and its financial strength, each mfi is assigned an upper limit n the amount that its borrowers can request from kiva each month. potential borrowers are screened by local mfis who re also responsible for disbursing the initial loan amount. in the majority of cases, mfis have already disbursed the full loan mount to borrowers before their loan requests are posted on the kiva website. therefore, while kiva gives the impression o charitable lenders that their decisions directly affect whether and how soon an individual borrower gets funding, the fine rint reveals that a lender’s decision generally has no impact on an individual borrower. loan requests are listed on the kiva c. jenq et al. / journal of economic behavior & organization ( ) – fig. . number of loans posted monthly and time to funding on kiva from january to december . website for up to days, and the mfi only receives the funds if the loan is fully funded within that period. it is very rare for loan requests not to be fully funded. borrowers and mfis agree on the repayment schedule and terms of the loan. while lenders on the kiva platform receive no interest on their loans, mfis do charge the borrowers interest. on average, the combined loan fees and interest paid by borrowers are about percent per annum. mfis are free to determine interest rates, but kiva monitors interest rates as a key evaluation criterion for determining whether to continue partnering with an mfi. field partners self-report to kiva the interest rates that they charge borrowers, and the average rate charged by that mfi across borrowers is reported on the kiva website, but not the individual borrower-specific rate. . . sample data our sample consists of loans first posted on kiva during june . this month was chosen to represent a typical month of operations from the period where kiva had already established mainstream status. we focused on only one month for our analysis as we wished to ensure a high quality of coding for each borrower’s physical and subjective attributes. more details on our coding procedure are discussed in the next subsection. while kiva began operations in , kiva experienced extremely rapid growth from to , as shown in fig. . kiva’s growth was accompanied by high-profile media events that attracted waves of new lenders, raising concerns that a sample drawn from that period might be less representative. we also wished to avoid drawing data from year-end holiday periods that might experience seasonal fluctuations in charitable activity. finally, we needed a sufficient period of time to elapse from the loan origination date, so we could evaluate final loan default rates. table outlines the characteristics of loans from to , as well as from our june sample. in the – data, the mean loan size is $ and the median loan size is $ . loans in excess of $ are rare, with the th percentile loan amount being $ and the largest recorded loan being $ , . the mean time to funding is minutes or about two and a half days, with the median time to funding significantly lower at minutes or about hours. a small number of loans take a week or longer to fund; the th percentile time to funding is , minutes, or days. the median loan term is months and the mean loan term is similar; the longest loan terms available on kiva are for months. our specific sample month of june appears similar to the broader data. we were able to track the performance of loans until september , when close to % of loans were paid in full, and . % of loans were in default. a small number of loans were classified as delinquent, in-repayment or refunded. pre-screening by mfis implies that the borrowers we observe on kiva are positively selected for characteristics that mfis expect lenders to prefer. while the mfi can choose the types of borrowers they prefer to loan to, mfis are not allowed to selectively post loans on kiva. therefore, our dataset covers the universe of loans made by the mfis during the sample period. during the period our data covers, this information was not reported on the borrower’s main loan listing and had to be accessed by clicking a link to view more information on the mfi. in recent years (not included in our sample period), after the kiva platform was revised, substantially more information about the field partner became available on the borrower’s main loan listing. our data contains the status of every loan posted on the kiva website during our sample period. the loan status indicates if the loan is due, repaid, currently in repayment, delinquent, or defaulted. information on the status of all loans ever posted can be accessed directly from the kiva website. c. jenq et al. / journal of economic behavior & organization ( ) – table summary statistics of loan listing characteristics. full data – data in analysis sample (june ) all data in sample individuals group mean std dev mean std dev mean mean loan data time to funding (minutes) . ( . ) . ( . ) . . loan amount (usd) . ( ) ( ) loan term (months) . ( . ) . ( . ) . . loan status as of september paid . ( . ) . . default . ( . ) . . delinquent . ( . ) . . in repayment/refunded . ( . ) . . microfinance institution partner data delinquency rate . ( . ) . ( . ) . . default rate . ( . ) . ( . ) . . gdp per capita, usd ppp . ( ) ( ) mfi risk rating ( – scale) . ( . ) . ( . ) . . fraction of total loans to female borrowers . ( . ) . ( . ) . . group borrowers . ( . ) . ( . ) count % of ttl count % of ttl % of ttl % of ttl agriculture , . . . . food , . . . services , . . . . construction, mfg. and tpt. , . . . . retail , . . . . others , . . . . geographic location africa , . . . . asia , . . . . central america , . . . . eastern europe . . . middle east . . . . north america . . . . south america , . . . . observations , n l t c w b a t d $ r d m a a t p d t l otes: summary statistics are based on all loans posted on kiva during the respective time periods of – (full data) and june (analysis sample). oans on kiva are classified according to economic sectors. we report separately the top economic sector classifications, and condense under “others” he classifications of arts, clothing, education, entertainment, green, health, housing, personal use and wholesale. “construction, mfg. and tpt.” is likewise ondensed from the classifications of construction, manufacturing, and transport. information on ex-ante credit risks is only available at the mfi level. thus, all borrowers from the same mfi are reported ith the same credit risk characteristics. in addition, no quantitative data is available on the economic conditions of the orrower except for the borrower’s country gdp per capita in purchasing power parity terms. based on this data, the verage delinquency rate is . %, while the median delinquency rate is % indicating that mfis with % delinquency issue he majority of loans. the average reported default rate of mfis in the sample is very low, and underestimates the actual efault rate of loans in the sample which is approximately . %. the mean ppp gdp per capita in borrowers’ countries is ; % of all loans are issued to borrowers in countries with gdps less than $ , . kiva also provides a to point risk ating for each mfi, displayed to potential lenders using a -star graphic. the star rating reflects the risk of mfi institutional efault. the median rating is points (mean rating approximately . ), indicating that the majority of loans are issued from fis that kiva assesses to be relatively low-risk. prospective lenders may search for loans through various methods. the main loan listing page presents a summary of ctive loans that includes, for each loan, a picture of the borrower, the entrepreneur’s name and loan activity, the loan amount nd percent funded, the name of the country and mfi as well as the first two to three lines of the textual description from he main borrower profile page. the order of the list is determined by the popularity of the loan, with more popular requests laced further up the list. loans are categorized according to the gender of the borrower, economic sector and geographic because kiva.org previously did not explicitly prohibit mfis from making repayments on behalf of defaulted borrowers, the data on delinquency and efaults provided may not reflect true loan performance. nevertheless, in our sample, the average default rate across all loans is about . %, ensuring that he mfis do not repay all loans that default. this discrepancy between the mfi default rate and the individual loan default rate likely arises because the mfi default rate is an average taken over a onger time period and the default rates of loans were significantly lower previously. c. jenq et al. / journal of economic behavior & organization ( ) – region. lenders can use these categories and a text search field to sort and filter for loans that match any desired keywords or phrases. loans can also be sorted based on popularity, loan amount, amount left, repayment term, and whether the loan is expiring soon or recently added. clicking on a loan brings up the borrower’s profile page, where the loan-specific details discussed above are displayed. appendix fig. provides a screenshot of both the main lending page and the borrower page. the last two panels of table show that the distribution of loans by economic sector and geographic region are broadly similar between the complete data and our coded sample. the most important sectors are agriculture, food (referring to food-based enterprises such as grocery stores and restaurants rather than personal consumption) and retail, which together account for two-thirds of all loans. slightly more than one-third of all loans are to countries in asia, followed by africa and south america. the remaining regions of the world make up less than % of all loans. loans in our sample are also broadly similar in terms of key listing characteristics such as the loan amount, loan term, mfi delinquency rate, mfi risk rating and the fraction of loans to female borrowers and groups. this again suggests that our sample month is reasonably representative of the broader data. . . coding procedures for physical and subjective borrower attributes from photographs to obtain measures of physical and subjective borrower attributes, the borrower photographs were reviewed by under- graduate research assistants. each research assistant was asked to code and quantify certain more objective qualities of each photograph, such as the number and type of people in the photograph, gender, physique, skin color and background setting as well as more subjective characteristics such as borrower attractiveness, perceived neediness, honesty and creditworthi- ness. a standard set of coding instructions, found in the appendix, was provided to each research assistant. we trained the research assistants by using a common set of borrower photographs. the coding for this common set was evaluated and discussed with each research assistant before they proceeded to the full task. to reduce the possibility of research assistant bias contaminating our results, each photograph was evaluated by a total of four coders - one male and one female coder from singapore and one male and female coder from chicago. all coders were undergraduates, and we ensured that the coders hired in each location reflected the majority demographics of that country. in total, we engaged forty-one coders, as photographs were randomly assigned to coders, and each coder worked independently, completing part of the entire dataset. for each of the physical and subjective characteristics, coders were asked to rate the primary subject(s) in the photograph on a scale ranging from to or to . in the case of a group loan, the characteristics were coded for the entire group as a whole. for example, for the attractiveness rating, coders were asked to rate the attractiveness of the person in the photograph on a scale of ( ) very unattractive to ( ) very attractive. we implicitly assume, in constructing and coding these scales, that there are common standards for these physical and subjective characteristics in the population (biddle and hamermesh, ). the literature on beauty has established that people seem to agree on who is attractive and who is not and these common standards seem to apply quite broadly across cultures and time periods (langlois et al., ; etcoff, ). our procedure to rate the borrower’s physique is similar to that for attractiveness, where coders are asked to place the person in the photograph on a scale from ( ) very underweight to ( ) very obese. to assess borrowers’ skin color objectively, we instructed coders to base their assessment on the massey and martin skin color scale ( ) from the new immigrant survey, which provides a reference visual skin color chart, and assigns a number from to for increasingly dark skin, with zero representing albinism. our definitions for the subjective borrower characteristics of perceived neediness, trustworthiness and creditworthiness are adapted from ravina ( ). to capture trustworthiness and honesty, coders were asked “if this person were to find a lost wallet on the street, do you think they would keep it for themselves, or try to return it (including the money)?” we also ask coders for their impressions on how needy the borrower is and the extent they are deserving of a kiva-type loan: “suppose you were deciding whether to lend $ (as part of a larger loan) to this person. do you think this person is more or less needy?” finally, we ask coders to assess whether the individual appears to have the ability to repay a kiva-type loan – “suppose you were deciding whether to loan $ . how likely is it that this person will repay your loan instead of default?” for each of the three questions, coders were asked to provide a rating on a scale ranging from ( ) very likely to keep wallet/definitely needy/very likely to default to ( ) very likely to return wallet/definitely not needy/very likely to repay loan. to generate a measure for each characteristic comparable across borrowers, we employed a ‘double standardization’ method. we first standardized each coder’s scores by transforming their individual ratings for each characteristic to have a mean of zero and a standard deviation of one. this measure captures the extent to which each coder considers a given borrower characteristic to be above or below average, based on the random subset of photographs they coded. we then con- structed a composite standardized score for each borrower characteristic, by averaging over all coders’ standardized ratings each research assistant was given a folder containing only the photographs of the borrowers. research assistants were told about the general purpose of the study but were not provided with any information on the borrower’s context, loan description, purpose, or amount. the primary outcome of interest, time to funding, is not directly available publicly and must be calculated from the raw data. we hired a total of research assistants to code the photographs – females and males based in singapore and females and males based in chicago. the research assistants from singapore coded an average of photographs each while the research assistants from chicago coded an average of photographs each. in the event of substantial heterogeneity in the characteristics of the group members, coders were asked to provide an ‘average’ rating and to indicate the existence of significant differences between group members in terms of the characteristic. c. jenq et al. / journal of economic behavior & organization ( ) – table summary statistics of physical and subjective characteristics (standardized measures) of borrowers. all individual group by region of borrower africa asia s america others attractiveness . . − . − . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) physique . . − . − . − . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) skin color . − . . . − . − . − . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) smile ( = yes, = no) . . . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) neediness . − . . . . − . − . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) trustworthiness . . − . − . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) creditworthiness . . − . − . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) observations notes: summary statistics are based on all loans posted on kiva in june . missing observations are due to a small number of missing photographs a s f o i t b c s s p a o s t t b o c a w o d r c i m a nd photographs where key borrower characteristics could not be coded. the physical and subjective characteristics are standardized variables with mean and standard deviation , derived from coded assessments of the borrower photographs by our research assistants. the text describes the coding and tandardization process in detail. standard deviations are reported in parenthesis. or that borrower characteristic, then transforming those average ratings to have a mean of zero and standard deviation of ne based on all borrowers in the entire dataset. a one unit difference in each standardized borrower characteristic is thus nterpretable as a one standard deviation difference in that characteristic’s composite rating. we prefer this procedure over aking the simple averages of ratings across coders as it controls for the possibility that each coder may have a different aseline scale. our results are robust to our standardization methods and to influences from idiosyncratic combinations of oders. table reports summary statistics of the physical and subjective characteristics of our sample, based on our composite tandardized score. while there is considerable variation in these measures across borrowers and regions, the means and tandard deviations of the variables are broadly similar, and reasonably consistent, across coders. the cronbach alpha has reviously been used in the literature on beauty to measure the consistency of ratings across different observers (biddle nd hamermesh, ; andreoni and petrie, ). the alpha coefficient ranges from to where a reliability coefficient f . or higher is generally considered “acceptable”. in our data, the cronbach alphas for attractiveness, physique and kin color are . , . and . , respectively. this suggests the standards of beauty held by our coders are more diverse han standards for physical weight, or perceptions of skin color. while the alpha coefficient for attractiveness is smaller han most previous studies, this could be due to the fact that borrowers in our sample come from a much wider range of ackgrounds. for the subjective characteristics, the cronbach alphas are . for neediness, . for trustworthiness and . for creditworthiness. appendix table presents the correlations between the coded physical and subjective attributes f the borrower, and the objective loan characteristics. . results . . determinants of time to funding in this section, we explore how borrower characteristics affect the speed of loan funding. we focus on three sets of haracteristics: ( ) hard information provided in the loan listing, ( ) physical characteristics observed from photographs, nd ( ) subjective characteristics inferred from photographs. we are interested in testing for evidence of discrimination – hether a borrower’s physical attractiveness, physique and skin color affect how quickly their loans are funded, holding all ther attributes of the loan constant. these other loan attributes, such as the purpose of the loan, loan amount requested, mfi while each photograph was rated by coders, a small number of photographs have only valid ratings because of data entry errors or perceived ifficulty in coding (research assistants were informed to leave entries blank if they felt they could not code the characteristic accurately). results using atings that require each photograph to have all four independent ratings are similar and reported in appendix table . regressions using non-standardized ratings obtain similar results, as do regressions that include fixed effects for each of the coder-group ombinations that assessed the data. the results are available from the authors. the cronbach alpha for beauty reported in biddle and hamermesh ( ) is . , and . in andreoni and petrie ( ). it is not surprising that the degree of agreement across coders for these subjective characteristics is lower than that for physique and skin color. this s consistent with alesina and ferrara ( ), who show that background factors play an important role in whether a coder finds someone trustworthy. oreover, there is likely to be greater subjectivity in determining a borrower’s perceived neediness, trustworthiness and creditworthiness from photographs lone. nevertheless, our consistency measures for trustworthiness and creditworthiness are similar to ravina ( ). c. jenq et al. / journal of economic behavior & organization ( ) – background, and so forth, are also important as they may provide information concerning default risks and social impact. we begin by estimating regressions of the form: yi = ̨ + xi ̌ + zi� + εi where yi is the log time to funding for each loan i, xi is a vector that includes the physical characteristics and subjective characteristics coded from the photographs, and zi is a vector that includes all the other characteristics of the loan listing and the borrower. the coefficients are interpretable as the effect in percentage terms of a linear unit change in the coefficient on the time to funding. objective loan characteristics zi include gender, an indicator for whether the loan is to a group or an individual, log of the loan amount, the repayment schedule in months, log gdp of the borrower’s country, the five-point rating of mfi quality and the average mfi delinquency rate. in all our specifications, we control for region fixed effects, fixed effects for the day the loan was posted and economic sector fixed effects. the physical characteristics of borrowers coded from the photographs include attractiveness, physique, skin color and a dummy variable that indicates whether the borrower is smiling. as discussed previously, the attractiveness, physique and skin color scales are based on the composite score derived from the four independent coders. the subjective characteristics of borrowers include perceived neediness, trustworthiness and creditworthiness. in the regressions that test whether photo-based physical and subjective characteristics matter, we include additional fixed effects for the borrower’s country ( countries), activity ( categories within sectors) and mfi ( field partners). in the appendix, we explore additional specifications using more flexible controls for the objective loan characteristics, as well as methods for measuring the quality of borrower text descriptions. estimates from our baseline model are robust to these additional specification checks (appendix tables a and b). as borrowers from the same country are more likely to possess correlated characteristics – due to genetics, economic structure, etc. – our models are estimated using robust standard errors clustered at the country level. the country level is also consistent with the general principle of selecting the coarsest level of clustering suitable for the analysis (cameron and miller, ). our empirical strategy first builds a preferred regression specification, using the complete june sample of photo- coded data, from the major components discussed above – objective loan, physical borrower, and subjective borrower characteristics. we then conduct sub-sample analyses by gender and by group vs. individual loans. these sub-sample analyses have particular external relevance as group and gender-based lending is a key strategy of microfinance lenders such as the grameen bank. our main results are presented in table . column ( ) reports estimates of only the objective loan characteristics, while ( ) adds borrower physical characteristics and additional fixed effects for country, activity, and mfi. ( ) is our preferred full specification which additionally contains borrower subjective characteristics. starting with the financial characteristics, larger loans take a longer time to achieve full funding – a % increase in the loan amount (about $ ) increases time to funding by about %. the estimate is stable across all specifications. while longer repayment terms increase time to funding by about % per additional month, this coefficient is not statistically significant in ( ). borrowers from higher-gdp countries take longer to receive full funding – but the estimates are not statistically significant. perhaps lenders believe social impact is higher when lending to individuals in poorer countries. mfi attributes produce mixed results. as expected, loans under mfis with high delinquency rates are funded slower, but mfis with worse overall ratings actually receive funding for their loans faster. one possibility is that low-rated mfis might serve countries or certain groups of borrowers that lenders favor. group loans are funded faster than individual loans, but the effect shrinks and is insignificant with the inclusion of borrower characteristics and additional fixed effects in ( ) and ( ). part of the group funding advantage could be operating through the presence of groups in regions or activities that lenders prefer. lenders strongly favor female borrowers – an all-women group (results are similar for loans to individual women) is funded % to % faster than loans to an all-men group. the gender effect increases as we add borrower characteristic controls, suggesting the preference is not just due to lenders assessing women as possessing more favorable (codifiable) characteristics. we discuss group and gender differences in more detail in the next section’s sub-sample analyses. next, we explore the effect of photograph-observed personal characteristics on lending decisions, controlling for the objective loan information included in ( ). we attempt to overcome typical omitted variable concerns that plague most observational studies of discrimination by controlling for much of the same information observable to the lenders (pope and snydor, ). in these specifications, we include a full set of fixed effects that control for the borrower’s country of origin, economic activity fixed effects and mfi fixed effects. by including the country and mfi fixed effects we subsume all the country-level and mfi-level covariates in ( ) and also control for all the observed and unobserved characteristics of mfis that could be correlated with the borrower’s personal characteristics and the time to funding. we first analyze the effect of the more objective physical borrower characteristics in ( ), and we then add the subjective borrower characteristics in ( ), which is our preferred full regression specification. in unreported regressions, we have estimated separately the effect of each borrower characteristic on time to funding, and also explored different combinations of borrower characteristics. the results are broadly similar to those discussed below. in our sample, all the loans were fully funded within the -day limit set by kiva. the gender variable, “fraction female,” is or for loans to individuals, and ranges from to for loans to groups. c. jenq et al. / journal of economic behavior & organization ( ) – table the effect of borrower appearance and loan characteristics on funding time of loans. outcome: ln(time to funding) ( ) ( ) ( ) attractiveness − . *** − . *** [ . ] [ . ] physique . *** . *** [ . ] [ . ] skin color . . * [ . ] [ . ] smile − . ** . [ . ] [ . ] neediness − . *** [ . ] trustworthiness − . *** [ . ] creditworthiness . [ . ] age . . ** [ . ] [ . ] children in photo . * . ** [ . ] [ . ] group loan − . * − . − . [ . ] [ . ] [ . ] fraction female − . *** − . *** − . *** [ . ] [ . ] [ . ] ln(loan amount) . *** . *** . *** [ . ] [ . ] [ . ] loan term (in months) . . *** . *** [ . ] [ . ] [ . ] mfi risk rating ( – points) . *** – – [ . ] mfi delinquency rate . * – – [ . ] mfi default rate − . – – [ . ] ln(gdp) . – – [ . ] controls for loan sector, region, posting day fixed effects yes yes yes country, economic activity, mfi fixed effects no yes yes observations r-squared . . . notes: each column is a separate linear regression. column ( ) is our main sample of kiva loans from june with non-missing borrower photos and at least three independent ratings for each of the borrower physical and subjective attributes used in the study. columns ( ) and ( ) uses the same sample but adds fixed effects for country, economic activity, and mfi partner, which require us to drop the mfi- and country-level characteristics. the physical and subjective characteristics are standardized variables with mean and standard deviation . the text describes the coding and standardization process in detail. standard errors clustered at the country level are reported in parenthesis. *** e o l t w $ m a t s b ( t significant at %. ** significant at %. * significant at %. we find strong evidence that borrower physical characteristics are associated with lender decisions even after controlling xtensively for other characteristics of the loan. lenders appear to strongly favor borrowers who are more attractive, less verweight and have lighter skin color, controlling for country of origin, sector, partner mfi and other characteristics of the oan. based on ( ), a one standard deviation (one unit) increase in assessed attractiveness is associated with a reduction in ime to full funding of approximately %, while a one standard deviation increase in assessed physique (obesity) is associated ith an increase in funding time of about %. for comparison, a ten percent increase in the loan amount requested, or about , is associated with an increase in funding time of about %. this implies borrowers who are one standard deviation ore attractive (overweight) are treated by lenders as though they were asking for $ less ($ more). funding times re also significantly lower for darker-skinned borrowers – a borrower one standard deviation darker is treated as though hey are asking for $ more. compared to other physical traits, the results on skin color are weaker in terms of statistical ignificance, and more dependent on the model specification. as a whole, these estimates showing apparent bias on the asis of physical characteristics are significant given that the average loan amount requested is about $ in our sample. we now examine the effect of subjective borrower traits – neediness, trustworthiness, and creditworthiness. comparing ) and ( ), we find that estimates of the effect of physical traits are minimally affected by the inclusion of these subjective raits. lenders appear to be independently considering both ‘outer’ and ‘inner’ beauty in their lending decisions. greater c. jenq et al. / journal of economic behavior & organization ( ) – table the effect of borrower appearance and loan characteristics on funding time of loans – subgroup analyses. outcome: ln(time to funding) individual loans only group loans only diff. between ( ) and ( ) individual loans to diff. between ( ) and ( ) men women ( ) ( ) ( ) ( ) ( ) ( ) attractiveness − . *** − . . − . * − . *** − . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] physique . *** . − . . ** . *** . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] skin color . ** − . − . . . − . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] smile . − . * − . ** . . . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] neediness − . *** − . − . − . *** . . *** [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] trustworthiness − . *** . . *** − . ** − . ** − . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] creditworthiness . . . − . ** . . *** [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] age . ** . − . . . * − . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] children in photo . ** − . − . * . . ** . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] fraction female − . *** − . ** − . [ . ] [ . ] [ . ] ln(loan amount) . *** . *** − . *** . *** . *** . * [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] loan term (in months) . *** . . . ** . *** . [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] controls for loan sector, region, posting day fixed effects yes yes yes yes yes yes country, economic activity, mfi fixed effects yes yes yes yes yes yes observations r-squared . . . . . . notes: each column is a separate linear regression. column ( ) reports the difference in coefficients between columns ( ) and ( ) and is based on a fully interacted regression model containing all the data in both ( ) and ( ). likewise, column ( ) reports the difference between the coefficients in columns ( ) and ( ) based on a fully interacted regression model. the physical and subjective attributes are standardized variables with mean and standard deviation . the text describes the coding and standardization process in detail. standard errors clustered at the country level are reported in parenthesis. *** significant at %. ** significant at %. * significant at %. perceived neediness and trustworthiness of borrowers is associated with faster time to funding. the magnitude of these effects is comparable to the effect of physical traits – a one standard deviation increase in the characteristic is associated with a reduction in funding time of % (neediness) and % (trustworthiness) respectively. however, there is no significant effect of creditworthiness on time to funding, in aggregate (though creditworthiness is significant in sub-group analyses, discussed shortly). the importance of neediness and trustworthiness to lenders on kiva contrasts strongly with the literature on for-profit peer-to-peer credit markets, which generally finds that creditworthiness is the key subjective borrower trait. ravina ( ) finds that creditworthiness, but not trustworthiness, matters. our results are quite comparable to ravina ( ) as we use the same methods of measuring creditworthiness and trustworthiness. duarte et al. ( ) argue that trust matters, but they use a measure of trust that actually includes a creditworthiness assessment. therefore, we interpret their findings as confirming that creditworthiness matters to for-profit lenders. unlike the for-profit market literature, we find lenders on kiva mainly appear to care about whether the borrowers need the money and are trustworthy in general. in aggregate, our evidence suggests creditworthiness matters less, conditional on other characteristics being accounted for in the model. this reinforces the importance of treating charitable lending as a separate and distinct market from for-profit lending. while certain biases are shared between markets, such as preferences for beauty, other underlying motivations behind credit decisions appear to diverge. . . subgroup analyses now, we investigate how estimated effects of borrower characteristics depend on group status and gender. while we found a slight preference for lending to groups earlier, here we examine whether lenders treat a given group borrower characteristic differently from the same individual characteristic. in columns ( ) and ( ) of table , we estimate our preferred f c a d a b p s c s b n a t g o d o k a d c p a t p s p p p r v p t d a a r ( a o l b c i d r i d c. jenq et al. / journal of economic behavior & organization ( ) – ull specification on the data restricted to individual and group borrowers, respectively. column ( ) tests whether the oefficients in ( ) and ( ) are significantly different, based on a fully interacted model. we find that estimates for physical nd subjective characteristics are significant for individual borrowers, but not for group borrowers. the magnitude and irection of the estimated effects are broadly similar – ( ) indicates coefficients are only significantly different for smiling nd trustworthiness. interestingly, the fact that trustworthiness is significantly less important for group borrowers could e consistent with the economic argument that joint liability and peer monitoring helps resolve individual moral hazard roblems (stiglitz, ; besley and coate, ; ghatak and guianne, ). however, we caution that our estimates likely uffer from measurement error in the group borrower characteristics. while we asked our coders to rate each group’s average haracteristics, lenders may actually be considering other aspects of a group’s characteristic distribution. therefore, in the ubsequent analyses following this sub-section, we base our estimates solely on individual borrower data, which forms the ulk of our data in any case. in columns ( – ) of table , we perform the same analysis, now split by gender rather than group status. we find o gender differences in the effect of physical characteristics, with more attractive and less overweight borrowers similarly dvantaged regardless of gender. we do find significant differences in the subjective characteristics. while greater neediness, rustworthiness and creditworthiness significantly reduce funding times for men, only trustworthiness matters for women. ender differences are particularly large for neediness and creditworthiness – the point estimates indicate almost no effect f neediness for women, but a substantial % reduction in funding time for a male borrower who appears one standard eviation needier. these results are interesting in light of the literature showing that the social impact of microfinance n children’s consumption, labor supply and household finances, is larger when women are borrowers, not men (pitt and handker, ). lenders who seek to maximize social impact could be targeting women in general (and ignoring differences cross women borrowers in perceived neediness), as well as selectively lending to more needy and more creditworthy men. . . probability of loan default here, we examine whether the observed patterns of bias are caused by lender statistical discrimination. the statistical iscrimination hypothesis predicts that lenders will be biased against observable borrower characteristics because those haracteristics are correlated with underlying default risks. kiva classifies as delinquent loans with one or more payments ast due, while a loan is classified as defaulted if six months elapse on a past due loan without full recovery of the loan mount. as of september , . % of loans were either delinquent or defaulted. one reason for kiva’s low default rate is hat mfis may cover non-performing loans in order to maintain their low average default rates. while this practice is currently rohibited by kiva, it was allowed from to . nevertheless, under the statistical discrimination hypothesis what hould matter to lenders is the overall likelihood of default, and whether the observable characteristics of borrowers are redictive of default. table reports linear probability model ( – ) and logit ( ) estimates of the relationship between loan default and the hysical and subjective characteristics of borrowers, controlling for the same loan characteristics as in table . the linear robability model used in column ( ) is based on the full regression specification in table . the logit model in column ( ) eports marginal effects estimated at the mean of the independent variables, and omits fixed effects because of insufficient ariation in default rates within many of our fixed effect categories. for comparison with the logit model, we include a linear robability model omitting fixed effects in column ( ). as observed from columns ( – ), we find little evidence that any photo-based characteristics are predictive of default. he appearance-based characteristics of attractiveness, physique and skin color, are not significantly associated with loan efault in all specifications. the subjective photo-based characteristics of neediness, trustworthiness and creditworthiness re also not associated with default. there is no evidence that default rates differ by gender, although female borrowers ttract funding much more quickly. we do not think our statistically insignificant findings are just due to the low default ates in the data – we are able to identify that higher loan amounts are associated with a lower probability of default in column ). thus, the evidence suggests there is no statistical relationship between discriminated-against borrower characteristics nd the actual probability of default. appendix tables a and b report several robustness checks for our results in this section. to address the concern that ur estimates are biased toward zero by the baseline low probability of default, we use the ‘rare events’ adjustment for the ogit model proposed by king and zeng ( ). we also incorporate the influence of fixed effects by first regressing each orrower characteristic of interest on the set of fixed effects, then using the resulting residuals in place of the borrower haracteristic variables in our logit models. results from the robustness checks are qualitatively similar and indicate little nfluence of borrower characteristics on loan default rates. we acknowledge a remaining limitation is that mfis may repay efaulting loans. we can rule out the case where mfis non-strategically repay all defaulting loans – defaults do exist and are as a conservative estimate, we code loans that are currently delinquent as having defaulted. as shown in table , virtually all of the loans that are not epaid had defaulted, with only a very small number recorded as another status (approximately . % of all loans were delinquent). the results are virtually dentical if we only focus on loans that have defaulted. the absence of fixed effects in columns ( – ) also provides a parsimonious model of statistical discrimination that reflects the case where lenders make ecisions mainly on the observable characteristics of borrowers rather than on the ancillary characteristics captured by our fixed effects. c. jenq et al. / journal of economic behavior & organization ( ) – table the effect of borrower appearance and loan characteristics on loan default. outcome: loan default linear probability model logit – marginal effects ( ) ( ) ( ) attractiveness − . − . − . ( . ) ( . ) ( . ) physique . − . − . ( . ) ( . ) ( . ) skin color . . . ( . ) ( . ) ( . ) smile − . − . − . ( . ) ( . ) ( . ) neediness − . − . − . ( . ) ( . ) ( . ) trustworthiness . − . − . ( . ) ( . ) ( . ) creditworthiness − . − . − . ( . ) ( . ) ( . ) age . − . . ( . ) ( . ) ( . ) children in photo − . − . − . ( . ) ( . ) ( . ) female − . . . ( . ) ( . ) ( . ) ln(loan amount) − . * . . ( . ) ( . ) ( . ) loan term (in months) . . . ( . ) ( . ) ( . ) controls for loan characteristics yes yes yes loan sector, region, posting day fixed effects yes no no country, economic activity, mfi fixed effects yes no no observations r-squared . . . notes: the sample is restricted to individual loans only. columns ( ) and ( ) report estimates from separate linear probability models. column ( ) reports the marginal effects at the mean of the independent variables from a logistic model. the sample includes all individual loans in our data sample that have available default status. column ( ) uses the same set of regressors as the individual loans model in table . columns ( ) and ( ) differ by excluding fixed effects for loan sector, region, loan posting day, country, economic activity, and mfi. instead of these fixed effects, the mfi rating, mfi default rate, mfi delinquency rate, and ln(gdp) of the borrower’s country are included in ( ) and ( ). standard errors clustered at the country level are reported in parenthesis. *** significant at %. ** significant at %. * significant at %. significant for some mfis. however, we do not have strong a priori justifications for formulating and testing any particular model of strategic mfi repayment behavior. we caution that defaults may be a noisy measure because of unobserved mfi repayments. . . differences across sectors next, we consider an alternate statistical discrimination test that is more robust to both unobserved mfi repayment behavior and low underlying default rates. this test assumes instead that lenders discriminate because they wish to maximize enterprise productivity and output, rather than just loan repayment performance. we believe this is a reasonable assumption since kiva’s published default rates are quite low, so lenders wishing to statistically discriminate may have considered more carefully potential output rather than default rates. the test requires identifying a borrower characteristic variable that is plausibly a priori associated with differential business productivity. we believe the most suitable variable is physical attractiveness. for example, strategic mfis might preferentially repay loans of borrowers known to be favored by lenders, to avoid ‘killing the golden goose’. but it is also possible that strategic mfis preferentially repay loans for less-favored borrowers if confirming negative stereotypes would greatly reduce funding access for those borrowers. the optimal strategy depends on the elasticity of lender money supply with respect to defaults. we do not have clear grounds for making assumptions regarding these parameters. finally, mfi strategic behavior (if it exists) is likely to be heterogeneous, since mfis differ widely in the types of borrowers they service. c. jenq et al. / journal of economic behavior & organization ( ) – table a more attractive borrowers sort into customer-facing economic sectors. outcome: attractiveness ( ) ( ) services . ** . ** [ . ] [ . ] construction, mfg and transport − . − . [ . ] [ . ] food − . − . [ . ] [ . ] agriculture − . − . ** [ . ] [ . ] retail omitted category omitted category observations r-squared . . controls for borrower characteristics yes yes loan characteristics no yes country, day, mfi fixed effects no yes notes: the sample is restricted to individual loans in the listed economic sectors only. each column is a separate linear regression with attractiveness as the dependent variable. each regression includes dummy variables for the following sectors: services; construction, manufacturing and transport; food; and, agriculture. the retail sector is the omitted category. “borrower characteristics” consists of gender, age, and presence of children. “loan characteristics” consists of the loan amount and loan term. standard errors clustered at the country level are reported in parenthesis. *** significant at %. s e p e m f a p m fi f a t c s s o b b i i m a t i r d ** significant at %. * significant at %. the beauty literature shows that relatively attractive individuals sort into customer-facing occupations such as sales and ervices, and earn premiums correlated with their attractiveness in these occupations (hamermesh and biddle, ; pfann t al., ). a lender who statistically discriminates with the aim of funding enterprises that are more likely to be highly roductive should therefore be more willing to fund attractive borrowers in customer-facing businesses. by contrast, the xtent of standard taste-based discrimination should be invariant to enterprise type, as the potentially higher output of a ore attractive borrower in a customer-facing enterprise should be less relevant. although a similar test applies in principle or other physical characteristics, lighter skin color and lower weight is not associated with higher productivity as generally s beauty itself. for example, while low physical weight may indicate good self-control and higher productivity, higher hysical weight may be a productive characteristic in a physically demanding enterprise. accordingly, we concentrate on investigating whether the effect of attractiveness on time to funding varies across five ajor economic sectors – agriculture, cmt (construction, manufacturing and transport), food, retail, and services. these ve sectors account for % of the loans in our sample. retail, services, and food (retail food) are more obviously customer acing sectors where attractiveness may allow an entrepreneur to be more successful. however, productivity in agriculture nd cmt are less obviously linked to attractiveness. we first document evidence of beauty-based sorting by borrowers on kiva into different occupations. table a presents he results of regressions of the borrower’s attractiveness on industry sector dummies. column ( ) includes other borrower haracteristics, while ( ) additionally includes loan characteristics and the full set of fixed effects used in our main regres- ion models. the results in table a show that borrowers in services are more attractive, by an average of . to . tandard deviations, than those in retail (the baseline). borrowers in food, cmt, and retail are statistically similar in terms f attractiveness, though the point estimates for food are somewhat lower. agriculture is associated with less attractive orrowers than retail. the evidence is consistent with some degree of sorting by attractiveness, with the more attractive orrowers entering services, followed by retail and cmt, then food, then agriculture. in table b, we examine whether the relationship between attractiveness and time to funding depends on the borrower’s ndustry. if lenders statistically discriminated to maximize productivity, we would expect greater effects of attractiveness n services and retail. panel a reports how the effect of attractiveness on time to funding varies by industry sector, using the ain regression model run separately on each industry sector. then, in panels b and c we test whether differences in the ttractiveness coefficient between sectors are statistically significant. specifically, panel b reports the difference between he effect of attractiveness in that industry and retail, while panel c reports the difference relative to services. the estimates n panels b and c are obtained from a fully interacted regression model with retail and services as the baseline sectors, espectively. we have conducted the same differential enterprise type analysis described in this section for physique and skin color and find no statistically significant ifferences across industry sectors in their effect on time to funding. the results are reported in appendix tables a and b. c. jenq et al. / journal of economic behavior & organization ( ) – table b the attractiveness premium does not depend on whether borrowers are in customer-facing economic sectors. sector outcome: ln(time to funding) retail services construction, mfg. and tpt. food agriculture ( ) ( ) ( ) ( ) ( ) panel a: coefficient of attractiveness by economic sector attractiveness − . *** − . *** − . *** − . *** − . *** [ . ] [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . panel b. difference in coefficient of attractiveness compared to retail sector attractiveness ( )–( ) ( )–( ) ( )–( ) − . ** − . *** − . [ . ] [ . ] [ . ] observations r-squared . . . panel c. difference in coefficient on attractiveness compared to services sector: attractiveness ( )–( ) ( )–( ) ( )–( ) . . . [ . ] [ . ] [ . ] observations r-squared . . . controls for loan and borrower characteristics yes yes yes yes yes loan sector, region, posting day fixed effects yes yes yes yes yes country, economic activity, mfi fixed effects yes yes yes yes yes notes: the sample is restricted to individual loans in the listed economic sectors only. each column in panel a is a separate linear regression with log time to funding as the dependent variable for each separate subsample of the data corresponding to the sector of the loan. each regression uses the same set of regressors as that of the individual loans model in table . panel b reports the difference in the coefficient of attractiveness relative to the retail sector (column ( )). panel c reports the difference in the coefficient relative to the services sector (column ( )). standard errors clustered at the country level are reported in parenthesis. *** significant at %. ** significant at %. * significant at %. the results in table b show that differences in the attractiveness premium across industry sectors do not support a model of statistical discrimination based on attractiveness as a proxy for productivity in customer-facing enterprises. panel b shows that the attractiveness premium for cmt and food is larger than that of retail. although food is also a customer-facing sector, it is unclear why the attractiveness premium for food should be superior to that of retail – and smaller than that of cmt. the attractiveness premium in cmt is particularly large; borrowers in cmt who are one standard deviation more attractive are fully funded percentage points faster than similarly attractive borrowers in retail. panel c shows the attractiveness premium for services – which the most attractive borrowers sorted into – is not significantly different from that of cmt, food, and agriculture. while services does have the largest attractiveness premium point estimate, overall, there is no consistent evidence that attractiveness matters more for industry sectors that are more customer facing. . experience, market power, and lender biases the results in the preceding section show that lenders appear to discriminate on the basis of borrowers’ physical attributes, and that such behavior is not readily explained by statistical discrimination. we cannot completely reject the general hypoth- esis that discrimination is motivated by the predicted effect of observable physical attributes on the social impact of loans, because we lack data on measurable social impact. however, our analysis of the available data provides evidence against both statistical discrimination based on default risk and statistical discrimination based on physical characteristics as a proxy for enterprise productivity. assuming that statistical discrimination does not explain our results, our findings are consistent with explicit or implicit discrimination by charitable lenders. while explicit (or taste-based) discrimination can be modeled as a conscious utility maximizing choice (becker, ), implicit discrimination may result from unconscious thought processes or attitudes (greenwald and banaji, ; greenwald et al., ). implicit discriminators may not even be aware of their discriminatory behaviors, which are more likely to be exhibited under time pressure, stress and cognitive load (bertrand et al., ). cognitive load may be the most relevant factor driving implicit discrimination on kiva, because of the extremely large choice set available – there are hundreds or thousands of borrowers seeking funds. evidence from multiple domains shows that decision making under ‘choice overload’ often results in qualitatively worse outcomes, ranging from reduced satisfaction and willingness to purchase goods (iyengar and lepper, ), to reduced tolerance for risk and complexity (iyengar and c. jenq et al. / journal of economic behavior & organization ( ) – table a summary statistics of lender data at the loan-level. no. of obs. mean std dev number of lenders per loan . . number of lenders per loan (individual loans only) . . length of time as kiva lender (months) , . . no. of previous loans made , . . table b loans to beautiful borrowers are more likely to be funded by less experienced lenders. average lender characteristics of loan number of previous loans made length of time as kiva member (months) attractiveness − . *** − . *** [ . ] [ . ] physique . *** . ** [ . ] [ . ] skin color . − . [ . ] [ . ] smile . ** . ** [ . ] [ . ] neediness − . − . *** [ . ] [ . ] trustworthiness − . * − . * [ . ] [ . ] creditworthiness − . − . [ . ] [ . ] age . ** . [ . ] [ . ] children in photo − . − . [ . ] [ . ] female − . *** − . [ . ] [ . ] ln(loan amount) − . . *** [ . ] [ . ] loan term (in months) − . * − . ** [ . ] [ . ] controls for loan sector, region, posting day fixed effects yes yes country, economic activity, mfi fixed effects yes yes observations r-squared . . notes: the sample is restricted to individual loans which have information on lenders available. each column is a separate linear regression with the average characteristics of lenders at the loan-level as the key dependent variable. standard errors clustered at the country level are reported in parenthesis. *** significant at %. ** k b t c a a r o c w t f significant at %. * significant at %. amenica, ). indeed, one common mental response to ‘too many’ choices or too much information is to reduce cognitive urden by using simplifying decision heuristics, such as stereotyping (rothbart et al., ; bodenhausen, ). our first test for the presence of implicit discrimination is based on the hypothesis that experience with a task reduces he extent to which implicit biases affect decision making. familiarity with the implicit association test is known to onsistently and robustly reduce test effect sizes across populations and in a variety of settings (nosek et al., ). lthough experimental psychologists argue prior experience confounds measurement of the ‘true’ level of implicit bias, we rgue this finding suggests that experience with a choice task may reduce a decision maker’s implicit biases, or at least educe the extent to which implicit bias affects choices made. therefore, if implicit discrimination explains the patterns f bias in our data, we should find that more experienced lenders exhibit less discrimination in their lending behavior. by ontrast, standard preference-based explanations for discrimination have no obvious correlation with experience. the implicit association test (iat) is a widely used measure of the strength of implicit associations. a test-taker is asked to associate stimuli (e.g., faces or ords) with categories (e.g., good, bad). the hypothesis is associations are made more quickly when the stimuli is implicitly related in the test-taker’s mind o the concept (e.g. african-american faces with ‘bad’ categories), relative to the cases where the stimuli are mentally unrelated (e.g. african-american aces with ‘good’ categories). a full description of the test is found in greenwald et al. ( ). c. jenq et al. / journal of economic behavior & organization ( ) – table the effect of competition on the extent of lender bias toward physical characteristics of borrowers. ln(time to funding) average lender characteristics of loan number of previous loans made length of time as kiva member (months) ( ) ( ) ( ) attractiveness*no. of competing loans (per ) − . − . ** . [ . ] [ . ] [ . ] physique*no. of competing loans (per ) − . − . . [ . ] [ . ] [ . ] skin color*no. of competing loans (per ) . ** . * − . [ . ] [ . ] [ . ] smile*no. of competing loans (per ) − . − . − . [ . ] [ . ] [ . ] no. of competing loans (per ) . *** . *** − . *** [ . ] [ . ] [ . ] attractiveness − . *** − . *** − . ** [ . ] [ . ] [ . ] physique . *** . *** . [ . ] [ . ] [ . ] skin color . ** . . [ . ] [ . ] [ . ] smile . . ** . *** [ . ] [ . ] [ . ] neediness − . ** − . * − . ** [ . ] [ . ] [ . ] trustworthiness − . *** − . *** − . [ . ] [ . ] [ . ] creditworthiness . * − . − . [ . ] [ . ] [ . ] controls for loan and borrower characteristics yes yes yes loan sector, region fixed effects yes yes yes country, economic activity, mfi fixed effects yes yes yes observations r-squared . . . notes: the sample in column ( ) is restricted to individual loans only, while the sample in columns ( – ) is further restricted to loans with available lender information at the loan-level. each column is a separate linear regression. column ( ) has log time to funding as the dependent variable while ( – ) have average characteristics of lenders at the loan-level as the dependent variable. “loan and borrower characteristics” consist of age, presence of children, female dummy, loan amount and loan term. the “no. of competing loans” is measured over a hour period and is scaled such that a one unit increase in the variable represents an increase in competing loans from the mean. standard errors clustered at the country level are reported in parenthesis. *** significant at %. ** significant at %. * significant at %. our analysis uses loan-level measures of lender experience and borrower characteristics as the units of observation, rather than lender-based measures. for each loan, we construct two measures that summarize the experience level of that loan’s lenders: ( ) the average number of loans made by lenders, and ( ) the average number of months that lenders have been kiva members. table a reports summary statistics for the lenders in our data, showing that the average lender made about previous loans and had months of experience on kiva. in table b, we regress these two measures of loan-level lender experience separately on borrowers’ physical and subjective attributes, controlling for the relevant loan characteristics as found in the baseline regressions. overall, the results in table b show that relatively inexperienced lenders are more likely to lend to more attractive and less overweight borrowers. skin color is not significantly related to lender characteristics, all else constant. less experienced lenders also tend to fund borrowers who appear more needy and trustworthy. interestingly, female loans are favored by less experienced lenders. these results suggest that lenders’ experience may alleviate bias toward the physical and subjective attributes of borrowers, consistent with findings that prior task experience reduces measurable implicit associations. for our second test, we contrast the predictions generated by models of discrimination (explicit vs. implicit) under varying degrees of competition or market power. explicit discrimination can be modeled as a non-pecuniary cost of market interaction (e.g. hiring, trading) with a discriminated-against group (becker, ). because these non-pecuniary costs are determined by the strength of prejudice, rather than the profitability of the market transaction, explicit bias can be competed away as less-prejudiced firms enter the market, and as markets become more competitive. for example, theseira ( ) a lender-based analysis requires reconstructing for each lender a full loan history, coding every past loan for that lender. the magnitude of data required far exceeds that of our present analysis. our present data only contains the loan history of very inexperienced lenders who have completed all their lending within the month of june . unfortunately, a lender-based analysis is outside the scope of this paper, but is an important area for future research. s b m o g o c c p o a t f h a i s a a d l h l w t t g u a l e s t d p b o ( f e t t w c a o y c. jenq et al. / journal of economic behavior & organization ( ) – hows that as competition intensifies amongst peer-to-peer lenders, interest rates fall more sharply for african-american orrowers than for white borrowers. accordingly, if explicit discrimination explains our results, we expect to find that arket power alters the magnitude of discrimination. a null effect of market power on discrimination suggests instead that ur results are not readily explained by explicit discrimination. to proxy for relative market power on kiva, we measure the aggregate demand for credit from borrowers, as we lack ood measures of credit supply by lenders. aggregate credit demand at the loan level is measured as the total count of ther loans posted during a -hour window, centered on the time that a given loan is posted. we de-mean and scale the redit demand measure so that a one-unit difference is interpretable as the effect of a -count change in the number of ompeting loans. the average loan faces competing loans, with a standard deviation of . in table , we examine how relative credit demand affects the extent of bias. we focus on bias toward attractiveness, hysique and skin color, as these are more relevant to the literature and have the most consistent effects on time to funding in ur data. column ( ) is based on the full regression specification from table , augmented with the credit demand measure, nd interaction effects between credit demand and borrower characteristics. however, we exclude group loans, and exclude ime-related fixed effects due to correlation with our credit demand measure. column ( ) shows that as relative demand or credit increases, so does time to funding – an additional competing loans increases funding time by about %. owever, credit demand generally does not affect the extent of bias. the interaction effects of the credit demand measure re significant only for skin color, where greater relative demand for credit exacerbates the effect of darker skin color on ncreased time to funding. while the results could suggest lenders are explicitly biased against darker skin, they are less upportive of explicit bias as an explanation for the effects of attractiveness and physique. we next replicate the lender experience regressions from this section, augmented with the credit demand measure nd interactions with borrower characteristics. as measures of loan-level lender experience, column ( ) uses the aver- ge number of loans, while column ( ) uses months on kiva. our main interest is in the interaction effects of credit emand, which show in ( ) that periods of greater choice are associated with even lower experience levels amongst enders to more attractive and lighter-skinned borrowers. this is consistent with the argument that the relatively igh cognitive burden from choice overload may increase the likelihood of implicit discrimination by inexperienced enders. overall, this section’s evidence is consistent with the hypothesis that implicit discrimination explains the patterns of bias e document on kiva. there is some evidence for explicit discrimination as an explanation for the effects of skin color on time o funding, but not for the effects of attractiveness and physique. we cannot completely rule out alternative models where aste-based or statistical discrimination is reduced by learning. however, models of explicit discrimination with learning enerally assume a setting where agents are both highly motivated to learn and have access to high quality information to pdate their priors – as in the labor market (altonji and pierret, ). our setting does not obviously fulfill these criteria. lender-based analysis would be a fruitful area for future research. . conclusion this paper documents systematic discrimination by charitable lenders in favor of borrowers who are more attractive, ess overweight and lighter-skinned. lenders also favor borrowers who appear more needy, honest and creditworthy. these stimates are economically significant: a one standard deviation increase in assessed borrower attractiveness, physique and kin-color is equivalent to asking for a loan amount of approximately $ less, $ more and $ more, respectively, relative o the average loan amount of approximately $ . we find little evidence that these patterns of bias are explained by statistical discrimination. borrower physical traits o not predict loan default, and the beauty premium is not significantly higher in industries where beauty might be a roxy for business productivity, such as services. we lack the data to directly test whether statistical discrimination occurs ecause borrower physical traits predict the eventual social impact of loans. however, studies show that less attractive, more verweight and darker-skinned individuals are denied opportunities in the labor market and in traditional credit markets hamermesh and biddle, ; cawley, ; pope and snydor, ; hersch, ). if anything, providing charitable unding to these discriminated-against groups should yield higher, not lower, social returns. since statistical discrimination does not readily explain our results, we believe lenders are displaying simple prejudice – xplicit or implicit – on the basis of borrower physical traits. we find tentative evidence consistent with implicit discrimina- ion against less attractive and more overweight borrowers. more experienced lenders appear to exhibit less bias, consistent we acknowledge that our tests will not conclusively distinguish between explicit and implicit discrimination. if market power implies greater choice, he cognitive constraints that cause implicit discrimination might be magnified. however, the link between market power and explicit discrimination is ell-established in the literature. a null result, at the least, is inconsistent with explicit discrimination explaining our findings. we use the -hour window because the median time to funding is less than a day. however, there is little difference in the effective variation of the redit demand measure if we use alternate time windows, or use the total amount requested from competing loans instead of the loan count. results using -hour window, a -hour window, and using the total amount requested by other loans are available from the authors. the interaction effects of credit demand are statistically significant using the prior loan measure of experience, but not when using the length of time n kiva measure. overall, we believe lender experience may be better measured using prior loans, since a member can belong to kiva for a long time but et have little actual lending experience. c. jenq et al. / journal of economic behavior & organization ( ) – with evidence from the implicit association test that shows task familiarity reduces the strength of implicit associations (nosek et al., ). moreover, we find that increased credit demand does not magnify prejudice against less attractive and more overweight borrowers – contrary to predictions from standard models of explicit discrimination. in fact, during periods of high credit demand, inexperienced lenders appear to exhibit even more bias – consistent with the cognitive burden from additional choices increasing reliance on implicit mental processes. we acknowledge competing explanations exist, such as statistical discrimination models where lender preferences are updated through learning. implicit discrimination remains an important area for future work, particularly since we conjecture many charitable donors would express discomfort with the idea that beauty or skin color should determine how charitable assistance is allocated. we add to a growing literature that shows discrimination on the basis of physical attributes also affects charitable sett- ings. however, our evidence is becoming more relevant as online directed giving or ‘crowdfunding’ continues to grow. microfinance institutions or charities that rely on individual giving may respond to lender biases by avoiding less ‘attrac- tive’ borrowers or clients, regardless of creditworthiness or social impact. direct philanthropy may thus be less efficient at allocating resources to maximize social impact, compared to traditional modes of giving where development experts make investment decisions based on presumably technocratic factors (desai and kharas, ). nonetheless, the scale and magnitude of direct giving through kiva and other platforms has the potential to be a remarkable force for development assistance. increasing public awareness of the existence of aggregate patterns of discriminatory behavior may do much to ameliorate lender biases, particularly if such biases are implicit (pope et al., ). appendix a. supplementary data supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/ . /j.jebo. . . . references agier, i., szafarz, a., . microfinance and gender: is there a glass ceiling in loan size? world dev. , – . alesina, a., la ferrara, e., . who trusts others? j. public econ. 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) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref http://refhub.elsevier.com/s - ( ) - /sbref beauty, weight, and skin color in charitable giving introduction literature review data . details on kiva.org . sample data . coding procedures for physical and subjective borrower attributes from photographs results . determinants of time to funding . subgroup analyses . probability of loan default . differences across sectors experience, market power, and lender biases conclusion appendix a supplementary data references swp .dvi beauty and the sources of discrimination∗ michèle belot†, v. bhaskar‡, & jeroen van de ven§ september , abstract we analyze behavior on a tv game show where players’ earnings depend upon several factors. attractive players fare better than less at- tractive ones, even though they perform no differently on every dimen- sion. they also exhibit and engender the same degree of cooperative- ness. nevertheless, they are substantially less likely to be eliminated by their peers, even when this is costly. our results suggest that discrimi- nation arises due to consumption value considerations. we investigate third party perceptions of discrimination by asking experimental sub- jects to predict elimination decisions. subjects’ predictions implicitly assign a role for attractiveness but underestimate its magnitude. keywords: discrimination, beauty premium. jel classification numbers: c , d , j , j . ∗we are grateful to dan hamermesh, gordon kemp, two anonymous referees and the editor (jörn-steffen pischke) for very useful comments and suggestions. we also thank seminar/conference participants at university college dublin, university of st andrews, university of amsterdam, university of essex (iser), the gate conference in lyon ( ) and the espe conference in chicago ( ). a special thanks to debbie hall for research assistance. †department of economics and institute for social and economic research (iser), university of essex, mbelot@essex.ac.uk. ‡department of economics, university college london, v.bhaskar@ucl.ac.uk. §department of economics and amsterdam centre for law and economics (acle), university of amsterdam. j.vandeven@uva.nl. introduction in a surprising and influential paper, hamermesh and biddle ( ) found a substantial beauty premium in the labor market, of the order of %. while there are several competing explanations for this premium, its source remains an open question. attractiveness may be correlated with unob- servable productive attributes such as health, education or other types of human capital. attractive people may be more confident, thus enhancing their social skills in the workplace. there may also be an element of reverse causality – individuals who fare well in the labor market may have both the ability and incentive (via greater self esteem) to invest in looking good. perhaps the simplest (and least palatable) explanation is that beauty has "consumption-value", either to the customers of the firm, fellow employees, or the boss. the beauty premium in this case is a form of taste-based dis- crimination, as discussed in becker ( ). while anecdotal evidence on the importance of consumption value considerations in the hiring of air hostesses or waitresses certainly exists, the question remains whether this is a more general phenomenon. more generally, as the literature on racial/gender discrimination shows (see altonji and blank, ; heckman, ), estab- lishing discrimination and distinguishing between statistical and taste-based discrimination is difficult. the main contribution of this paper is to disentangle the sources of advantage to attractive people. we do this in the context of a tv game show where participants are engaged in a variety of "tasks". we can ask: are attractive people more productive, and do they exhibit greater confidence? are they more cooperative or do they engender cooperation? are they more likely to be chosen by their peers when a selection decision has to be made? we are able to answer these questions since the game show has a rich structure, with players being involved in a number of different tasks see mobius and rosenblat ( ) for experimental evidence in favor of this hypothesis. biddle and hamermesh ( ) address the reverse causality problem in a study on lawyers by using a measure of beauty based on photographs taken at law school. and decisions. it takes place over three rounds, in which players accumulate "earnings" by answering quiz questions, and their earnings depend on the accuracy of their answers, on how quickly they press the buzzer and also on their "investment decisions". earnings therefore depend upon ability as well as a player’s confidence. this allows us to study the effect of attractiveness as well as other player characteristics upon performance. at the end of each round, the lead player – the one with the highest earnings – decides which one of the remaining players to eliminate. this allows us to study the role of attractiveness and gender (in addition to performance) upon the selection decision. after the final round, when only two players remain, they play a prisoner’s dilemma game, allowing us to study the relation between beauty and cooperativeness. the median stake in this prisoner’s dilemma game is € , , so that the monetary consequences of players’ decisions are substantial. we find that attractive players fare significantly better than unattractive ones. players can only make positive earnings by making it to the final prisoner’s dilemma stage of the game show. only % of the least attractive players make it to the final round, as against % of the most attractive ones. this difference cannot be attributed to any aspect of performance – attractive players fare no differently from unattractive ones in answering questions or in investment behavior. they are no more likely to cooperate in the final stage, and opponents also behave no differently vis-a-vis them. nevertheless, when one player has to be eliminated by the lead player, the least attractive player of a show is significantly more likely to be chosen. our results support a "consumption value" basis for discrimination. dis- criminating in favor of attractive players is not simply used as a tie-breaking rule between otherwise similar players. unattractive players are more likely to be eliminated even when they have a higher score than others. this is costly to the lead player, implying an adverse selection in terms of earning potential. we estimate that the average cost to lead players from discrimi- nation in the final round alone amounts to about € , i.e. about percent of the median stake. this is an underestimate of the overall costs of dis- crimination over all the rounds. in view of our finding that attractiveness is unrelated to cooperativeness in the prisoner’s dilemma, this cost has no offsetting financial benefit. it is noteworthy that we find discrimination against the unattractive on a tv show, where each player’s performance is clear-cut and where the lead player’s decision is subject to public scrutiny. other studies using tv shows (levitt ( ), antonovics et al. ( ) and list ( )) find no evidence of discrimination on the basis of race, gender or ethnic background, but some weak evidence of discrimination against older players (these papers do not examine the role of beauty). discrimination on the basis of looks may not be so imprinted in social consciousness as racial or gender discrimination, so that people are not so aware of the possibility of discrimination, i.e. such discrimination may be insidious. to investigate third party perceptions of discrimination, we ran an experiment where subjects watched the game show and had to predict elimination decisions. our subjects predict that attractive players are less likely to be eliminated, although they substantially underestimate the magnitude of this effect. we also ask our subjects to list qualitative factors that influence elimination decisions, and find that very few subjects mention attractiveness. thus third parties appear to be aware of the possibility of discrimination subconsciously rather than consciously. we also present suggestive evidence that discrimination on the basis of looks appears to entail less social opprobrium than racial discrimination, making it easier to survive and persist. the remainder of this paper is organized as follows. section reviews the related literature. section describes the game show and our construction of the measure of attractiveness. section analyzes behavior on the game show, in terms of performance and cooperation. section studies the selec- insidious is defined as "working or spreading harmfully in a subtle or stealthy manner" (answers.com). tion decisions by lead players and establishes that attractive players benefit in this context. we also examine gender differences and find significant dif- ferences in performance between men and women, with the result that there does not appear to be any evidence of discrimination against women. this section also presents our experimental findings on third party perceptions of discrimination. the final section concludes. related research following the work of hamermesh and biddle ( ), who find a beauty premium in the labor market in a variety of occupations, several papers have replicated its findings, and also attempted to disentangle the components of the premium. biddle and hamermesh ( ) analyze a sample of lawyers, and find a premium irrespective of their area of expertise, including the self- employed. they argue that the most plausible explanation is taste-based discrimination by clients. mocan and tekin ( ) find that unattractive people sort into criminal activity due to the existence of a beauty premium on the legal labor market. there are two difficulties with field studies. first, data on attractiveness is rarely available. second, it is difficult to disentangle attractiveness from ability, since productivity is rarely observable. this makes it hard to estab- lish whether the beauty premium is due to productivity or discrimination. such productivity effects are sometimes present. landry et al. ( ) find that attractive female solicitors are more productive fund-raisers. pfann et al. ( ) study a sample of dutch advertising firms and find that those with better looking executives have higher revenues – this is particularly pertinent for our paper, since it demonstrates that beauty plays a role in the netherlands. laboratory experiments are better suited to disentangling the sources of the beauty premium, since they can be designed for this purpose. mobius and rosenblat ( ) take this approach, using university students in ar- gentina. they find that the beauty premium appears to be partly due to the fact that attractive people are more confident. since our results differ from theirs — we find that beauty is unrelated to actual confidence, as re- flected in behavior, although it is correlated with third party perceptions of confidence – we discuss their paper in more detail in section . . , while presenting these findings. benjamin and shapiro ( ) find that experi- mental subjects are able to predict the electoral fortunes of candidates on the basis of -second silent video clips, suggesting that attractiveness (or charisma) plays an important political role as well. there is a large literature on discrimination on the basis of race or gender (see altonji and blank ( ) for a survey). one difficulty in labor market studies is in establishing discrimination – see, for example, the criticisms of heckman ( ). bertrand and mullainathan ( ) conduct an field ex- periment which circumvents these criticisms and shows convincing evidence of employer discrimination against african-american names. however, it remains an open issue whether such discrimination is statistical or taste based, since employee performance on the job is not observable. description of the data . the game show we use data from all episodes of the game show ‘does (s)he share or not?’, broadcast in the netherlands in , with contestants in total. in the preliminary stage of the game, six prospective players choose their initial capital, a number between one and . the player with the highest choice is eliminated, leaving five players for the game proper. figure shows the structure of the game. the game then proceeds with three quiz rounds, where players accumu- the name of the show in dutch is ‘deelt ie ’t of deelt ie ’t niet?’. the format of this preliminary elimination stage was slightly different in the first few episodes. pre-stage (initial capital) investment decision regular q.’s regular q.’s investment and play bonus q. elimination decision quiz round quiz round prisoner’s dilemma stage quiz rounds details quiz round figure : timeline of the game show. late earnings. every round has ten regular questions and a bonus question. players first choose how much of their capital to "invest" in answering each question (yi). whoever presses the buzzer first gets to answer. a correct answer yields yi, while an incorrect answer earns −yi. a player whose cap- ital falls below his or her chosen investment may not answer any further questions. each round ends with a bonus question, where players compete for the right to answer the question by choosing new investments. at the end of the round, the player with the highest score at that point – the lead player henceforth – must select one of the remaining other players for elimination. an eliminated player has no further role in the game and loses all of his or her earnings. the show then proceeds to the next round, where all players start with a capital that equals the earnings of the lead player in the previous round. the last two remaining players play a prisoner’s dilemma game. let e denote the total prize money, which equals the sum of earnings of the two finalists. the finalists simultaneously decide whether to share or to grab. the monetary payoffs, as depicted in table , correspond to a generalized prisoner’s dilemma, where grab is a weakly dominant strategy. table - monetary payoffs share grab share e, e , e grab e, , table presents summary statistics of the game show and the players. the total prize at stake varies between € and € , , with a median value of € , . players choose to share % of the time in the final round. the age of players varies between and with an average of . . about a third of players is women. of the third of the players who report their occupation, one-third is student, while the others are drawn from all the important sectors (at the two-digit classification level), including trade, information technology, education, financial services and health. table - summary statistics, game show players mean min max mean age (years) (n = ) . percentage women (n = ) . - - prize (€) (n = ) , percentage sharing (n = ) . - - . measure of beauty hamermesh and biddle ( ) argue that there are consistent standards of beauty within and even across cultures, so that subjective evaluations of attractiveness include a "common component". our goal is to see how this common component affects performance on the game show. to this end, each of the participants on the game show were rated on a scale from (very unattractive) to (very attractive) by approximately raters, balanced by gender. raters were recruited in public spaces to obtain a representative sample of the adult population. raters were on average . years old, which is close to the average age of game show participants, years. we recruited raters, and each rated participants. this was based on watching short silent video fragments of the game show in which a player introduced him or herself. we ensured that all five players on any show were rated these are considerable sums given that the median disposable monthly income of a full-time employed person in the netherlands was about € , in (statistics netherlands, available at www.cbs.nl). by the same set of raters, while varying the order in which the shows were presented. about one-third of the raters were non-dutch and could not be familiar with the show, and only a small minority of the dutch raters indicated that they had seen any episode of the show. given this, and the fact that the game show was broadcast five years prior to the ratings, our results are not distorted due to familiarity with the faces. our measure of attractiveness is the average of the independent ratings (across raters) for each player. there is a high degree of concurrence on at- tractiveness across raters. across sub-samples of raters who rated the same sample of players, the cronbach’s alpha ranged from . to . , showing high agreement. table reports summary statistics of the ratings. raters were told to use the benchmark average attractiveness in the population at . somewhat surprisingly, the average rating across participants is . , i.e. lower than the benchmark, so that there does not appear to be any positive selection into the show according to attractiveness. beauty is negatively cor- related with age and women are, on average, rated as being more attractive than men. average ratings are more variable across women than men, con- sistent with other studies (hamermesh and biddle, ). we also coded objective participant characteristics that are related to their appearance, such as eye-color, hair-length, wearing of glasses, etc. these characteristics are correlated with our beauty measure – for women, beauty is positively correlated with hair-length, while for men, beauty is negatively correlated with having a beard or moustache and wearing glasses. this suggests that our measure of beauty captures aspects of physical attractiveness. raters may have different perceptions on the average beauty. to correct for such differences, some other studies use standardized measures. each rating is adjusted for the mean rating of that rater, and is then normalized by dividing by the standard error (see e.g. mobius and rosenblat, ). we chose to have many different raters rating different subjects. the means are not comparable among raters, because the sample of episodes they rated were partly different. we therefore prefer to use the raw data. however, if we standardize ratings for the subsamples of ratings made for the same players, the results remain very similar. table - summary statistics attractiveness mean (st. dev.) min max all (n = ) . (. ) . . men (n = ) . (. ) . . women (n = ) . (. ) . . age ≥ (n = ) . (. ) . . age < (n = ) . (. ) . . note: attractiveness of players is averaged across raters. beauty and behavior given the many potential determinants of performance and monetary pay- offs on the show, we study each of these in turn. . beauty and performance we first investigate the relationship between beauty and performance in an- swering quiz questions. the total earnings of a player in a round is probably the most important measure of overall performance. the player with the highest earnings becomes the lead player for that round, making the elimi- nation decision. in the first two rounds the lead player’s earnings determine the initial capital for all remaining players in the next round. in the third round, a player’s earnings are added to the total stake, if he is either the lead player or not eliminated by the lead player. our focus is mainly on the first round, since this is the round with the least prior selection. since players compete to answer each question, their performance in the game is a relative measure. if there is a relation between beauty and performance then this will depend on the composition of players within an episode. hence, we cannot draw conclusions from simple cross-correlations over episodes. instead, we look at the relationship between attractiveness and relative ranking in the game. two player positions, the first and the last, are of particular interest. the player who is ranked first in terms of earnings must choose one of the others for elimination, and cannot be eliminated himself in that round. the last ranked player is an obvious candidate for elimination. we estimate a conditional logit model for the probability of being in the first or last position conditional on participating in the same episode. the conditional logit is a natural framework for modelling choices from a set of alternatives. in our context, the alternatives are the players in the round, and each player i in show j has a vector of attributes xij (gender, age, attractiveness). the conditional logit model has the form: p(yij = ) = exp(β xij)p i exp(β xij) for i = , ... , where yij is an indicator variable which takes value one when the player is in the first (respectively last) position. the results are reported in table , columns and . in addition to at- tractiveness, we also control for age and gender, and for a number of dummy variables describing the register of the introductory speech: whether the player mentions his marital status, whether he has children or not, talks about his profession or studies, or about his hobbies. attractiveness is un- correlated with the probability of ending first or last. only one covariate turns out to be significant; players who mention their marital status are less likely to be ranked first. to investigate further the correlation between the players’ attributes and their rank in terms of earnings, we estimate a rank-ordered logit model (a refinement of the conditional logit) that ex- plicitly takes account of the ranking of players within a game and specifies this ranking as a function of their relative attributes. the results are re- ported in the third column of table . we find no clear correlation between any of these characteristics and earnings ranking. in particular, there is no evidence that attractive people rank differently from unattractive ones. one important assumption for the validity of the conditional logit estimates is inde- pendence of irrelevant alternatives. our tests show that this assumption is not rejected. table - attractiveness and performance, st round ( ) ( ) ( ) prob. ranked first prob. ranked last score ranking end of st round attractiveness . (. ) . (. ) -. (. ) age . (. ) . (. ) -. (. ) female -. (. ) . (. ) -. (. ) register of introductory speech - is married / has a partner - . (. )*** -. (. ) -. (. ) - children . (. ) . (. ) . (. ) - study / profession . (. ) . (. ) -. (. ) - hobby - . ( . ) -. (. ) . (. ) n. obs. pseudo r-squared . . - method cond. logit cond. logit rank- ordered. logit notes: *** % significance level, in col ( ), is lowest score and highest. . . decomposing performance performance in this game depends on a number factors: the choice of ini- tial capital and investment, the decision to press the buzzer or not, and, finally, the answer itself. these decisions depend upon the player’s ability, confidence, and risk aversion. mobius and rosenblat ( ) argue that con- fidence explains a substantial part of the beauty premium. they find that "employers" have higher estimates of the productivity of more attractive in- dividuals, even though they are given independent evidence on productivity. an intriguing finding is that attractive subjects are estimated to have higher productivity even when their interaction with the employer is only oral, not visual. mobius and rosenblat attribute this to the higher self-confidence of attractive workers, and this explains about % of the beauty premium. in the context of this game, we would expect highly confident players to be more active in the game in terms of investment and answering questions. recall that by being the first to press the buzzer, player i faces a lottery where he gets yi (his chosen investment level) if he is correct, and gets −yi if incorrect. let pi be the subjective probability assigned by i to his answer being correct. let xi be his current score, and let vi(.) denote his expected continuation value in the game after this question. it is optimal for player i to answer to the question if his expected continuation value from answering is weakly greater than his value at the current score. this implies that player i will answer the question if pi exceeds a critical threshold: pi ≥ vi(xi)−vi(xi −yi) vi(xi + yi)−vi(xi −yi) ≡ p̄i, where p̄i ∈ ( , ) as long as vi is strictly increasing in the player’s earn- ings. notice that the threshold value, p̄i, is larger if the player is more risk averse, i.e. if vi(.) is more concave. since we observe the frequency of correct answers for every player, we have an estimate of qi, the objective probability that a player is correct conditional on answering. that is, we have an estimate of e(qi|pi ≥ p̄i). a player who is more risk averse will have a higher threshold value p̄i, and will therefore answer fewer questions but be observed to answer a greater proportion of questions correctly. a player who is more confident – i.e. has a greater value of pi for a given qi – will answer more questions and will make more mistakes. in other words, risk aversion and lower confidence act in very much the same way, in reducing both the number of answers and also the proportion of incorrect answers. on the other hand, if a player is less knowledgeable, and objectively has a lower value of qi, this will ceteris paribus reduce the number of answers but not raise the proportion of correct answers. we concentrate our analysis on the decisions made in the first round, since the second and third rounds could be subject to selection biases due as the player thinks about the question, his subjective probability will evolve over time. the analysis that follows pertains to any instant of time, so the continuation value from not pressing the button (vi(xi)) includes the option value of waiting, and possibly pressing the buzzer in the future, if no one else presses in interim. to the elimination decision. table presents the results of ols estimates of the determinants of initial capital, share invested, number of answers and percentage of good answers (columns to respectively). we do not find that attractive players are more confident. if they were, they should invest more, be more likely to answer, and, conditional on answering, perform worse. we do find a systematic difference according to gender: women are much less likely to answer a question. this is what you would expect if women are more risk averse or less confident. however, conditional on answering, they actually do not perform better than men, what you would expect with risk aversion or lack of confidence. in the second round, we even find that they are significantly less likely to answer correctly. we also did not find any evidence that the topics of the questions could explain gender differences in performance. overall, these results suggest that the reason why women are less likely to answer is not due to a wrong perception of their ability or a higher degree of risk aversion, but rather because they are less able to answer the type of questions on the show. our measure of confidence is based on actual behavior. it could be the case that attractive players areperceived more confident by other players. to investigate this, we constructed a measure of perceived confidence, by hav- ing independent raters assess the confidence of a player on a point scale. each player was rated by to raters, and each rater saw players. our player specific measure of confidence is the mean across raters. column ( ) of table shows the results of an ols regression of perceived confidence on the characteristics of the players. we find that perceived confidence is sig- nificantly positively correlated with attractiveness. thus, attractive players appear more confident but do not behave more confidently. the reason for we have analyzed separately the decisions made for the bonus question. again, we found that attractiveness is uncorrelated with the share invested or the probability of giving a correct answer. the results are not reported for the sake of brevity. alternative econometric specifications (conditional logit estimates for the probability of answering and logit estimates for the probability of answering correctly) give similar results to the ones presented here. table - attractiveness, performance and confidence, st round ( ) ( ) ( ) ( ) ( ) initial capital share invested n. of answers share correct answers perceived confidence attractiveness . ( . ) -. (. ) . (. ) -. (. ) . (. )*** age . (. )*** -. (. )** . (. ) -. (. ) . (. ) female -. ( . ) . (. ) -. (. )*** . (. ) -. (. )*** register introductory speech - is married/partner . ( . ) . (. ) -. (. )** -. (. ) . (. ) - has children -. ( . ) -. (. ) . (. ) . (. ) . (. ) - study / profession . ( . ) . (. )* -. (. ) . (. ) . (. )** - hobby - . ( . ) -. (. ) . (. ) -. (. ) -. (. ) constant . ( . )*** . (. )*** . (. )** . (. ) . (. )*** n. obs. notes: ols estimates, * significant at % level, ** % level and *** % level, col ( ) include players who gave at least answer. standard errors are clustered by episode in col ( ) to ( ). col. ( ) includes predictor fixed effects and standard errors are clustered at the player level. our finding may be that players receive continuous feedback on their per- formance. this contrasts with the set-up of mobius and rosenblat, where subjects did not receive systematic feedback on their performance through the experiment. we should also mention that in their study, there is no inter- action between subjects who are assigned the role of "employers" and those assigned the role of "workers", so that consumption value considerations may be naturally less important. . beauty and cooperativeness players can only materialize their gains in this game in the final stage, where the two remaining players play a prisoner’s dilemma game and de- cide simultaneously to share the accumulated money or not. a companion paper (belot et al., ) conducts a comprehensive analysis of the deter- minants of sharing behavior. the key findings are that own characteristics matter – specifically, women are more likely to share than men. however, the characteristics of the opponent turn out to be irrelevant to the sharing decision. we augment this analysis by including the player’s own beauty rating and the opponent’s beauty rating as explanatory variables. the results are reported in table . we find no correlation between beauty and cooperative behavior. attractive players are no more (or less) likely to share – indeed, the coefficient is very close to . attractive opponents are also no more (or less) likely to induce sharing behavior from their opponents. this is interesting – although our overall results suggest that players obtain con- sumption value from having attractive co-players, they are no more likely to share with them. it is possible that attractive people are perceived as being more coopera- tive even though they are not really so, so that selection decisions are driven by incorrect beliefs. while we do not observe the beliefs of participants on the show, a companion paper (belot et al. ( )) experimentally inves- tigates third party perceptions of trustworthiness. experimental subjects watched a random sample of shows and were asked to report a probability that a player would share. column of table reports our findings on the relation between beauty and perceived cooperativeness. our subjects predict that attractive people tend to be slightly less cooperative, although the effect is small. it therefore appears that attractive people are not only not more cooperative, they are also not perceived to be more cooperative by third parties. the coefficients are potentially biased if lead players use private signals to select players, since the sample of unattractive players may be unusually cooperative. belot et al. ( ) addresses this issue and find no evidence of bias. other experimental evidence on the relation between attractiveness and cooperation is mixed – see mulford et al. ( ), solnick and schweitzer ( ), eckel and wilson ( ) and andreoni and petrie ( ). table - attractiveness, sharing & perceptions of sharing ( ) ( ) ( ) pr. sharing pr. sharing perceived prob. sharing own attractiveness -. (. ) -. (. ) -. (. )** opponent’s attractiveness -. (. ) age . (. ) . (. ) . (. ) female . (. )** . (. )** . (. )*** contribution to prize money (%) -. (. )** -. (. )** -. (. )** total prize (x € , ) . (. )** . (. )*** . (. )*** constant . (. )*** n. obs. method bivariate bivariate ols probit probit notes: * significant at % level, ** % level and *** % level; ( ) and ( ) are bivariate probit estimates, standard errors clustered by episode; the marginal effects in ( ) and ( ) are computed at the means of the lead player’s characteristics. ( ) includes subject fixed effects. beauty and selection we now study the elimination / selection decision, having established that there is no objective reason to discriminate in favor of attractive players either on the grounds of performance or because they are (thought to be) more cooperative. thus any bias towards attractive players in lead player selection decisions can plausibly be attributed to the lead players obtaining consumption value from having attractive co-players. an important advantage of the rules of our game show is that in mak- ing the elimination decision, the lead player in any round is faced with a relatively simple decision problem, rather than a game. if the lead player chooses to eliminate player i then the lead player is decisive and i will play no further part in the game. in contrast, elimination decisions in other game shows (such as the weakest link, analyzed by levitt ( ) and antonovics et al. ( )) are often made by majority voting, involving all the partici- pants remaining at that stage. if a player j votes to eliminate i, then i may not be eliminated, and may in turn vote against j at a later stage. this implies that players have a strong incentive to vote to eliminate whoever they think others are going to vote against. in other words, there are mul- tiple voting equilibria, and this is coupled with a strategic dynamic motive to vote with the majority. this may induce a significant role for irrelevant characteristics as possible focal points, even when players do not have any preference for discriminating on the basis of such a characteristic. in the context of our game, these strategic considerations do not apply, since only the lead player votes and his vote is decisive. thus evidence of discrimination can be attributed to lead player preferences. figure shows the average attractiveness of all players in each round, and that of the players who are eliminated in that round. in each round, eliminated players are less attractive than average, and in consequence, av- erage attractiveness increases steadily over the rounds. other summary statistics confirm this picture. if a player is average-looking (i.e. within one standard deviation of the mean), he or she has . probability of reaching the final round. an attractive player has a substantially higher probability of . , while an unattractive player’s probability is only . (see table ). table - attractiveness and survival, by round % reaching % reaching % reaching round round final attractive average-looking unattractive note: attractive (unattractive) is more than one standard deviation above (below) the mean. we investigate in more detail the role of physical attractiveness in the selection decision by the lead player by estimating a conditional logit model, where the dependent variable indicates whether the player was eliminated . . . . . . . round (n = ) round (n = ) round (n = ) final (n = ) ave ra ge bea uty players all players eliminated player figure : average beauty of all players and eliminated players. ( ) or not ( ). we start by focusing on the first round, where the sample is largest and no selection has taken place. later on we discuss results for other rounds. the results are shown in table . the first regression includes no other covariates, the second controls forperformanceand individual characteristics and the third controls for measures of confidence. the results are reported in terms of odds ratios with a reference value of . these have an easy interpretation. an odds ratio above (below) signifies that the attribution increases (decreases) the probability of being eliminated. we find that unattractive players are significantly more likely to be elim- inated than average-looking players. when we control for performance and measures of confidence, we predict that unattractive players should be three times as likely to be eliminated as average-looking players. in contrast we do not find that more attractive players are better treated. hence, our re- sults point in the direction of an ugliness penalty, in line with the results of hamermesh and biddle ( ). table - probability of being eliminated, st round conditional logit estimates (odds ratios) ( ) ( ) ( ) attractiveness unattractive . ( . )* . ( . )** . ( . )** attractive . (. ) . (. ) . (. ) performance fourth highest . (. )** . (. )*** third highest . (. )*** . (. )*** second highest . (. )*** . (. )*** confidence % capital invested . (. ) n. answers . (. ) perceived confid. . (. ) female . (. ) . (. ) age . (. ) . (. ) controls for topic registry introduction no yes yes n. obs. pseudo r-squared . . . notes: significance levels: *: percent, **: percent, ***: percent. note that age and gender are irrelevant in the selection decision. also, the score ranking is a very good predictor of elimination: the player with the lowest score (the reference category) is more than twice as likely to be eliminated as the one ranked fourth, and more than five times as likely to be eliminated as the one with the second highest score. finally, controls for behavior during the game do not change the results and do not matter as such in the selection decision (column ( )). less attractive players are dis- criminated against, for reasons that are uncorrelated with their performance or behavior during the game. . discrimination over the rounds one explanation for the discrimination taking place in the first round is that players have very little information about each other. they had relatively little time to get to know each other and to learn about each other’s ability. with so little information, perhaps they retreat to attractiveness to select one player over another. if this is the reason, we expect discrimination to disappear over the rounds when more information becomes available. however, since discrimi- nation takes place in the first round, the population of players becomes more attractive on average and less heterogeneous, which should reduce discrimi- natory practices. the fact that there are fewer unattractive people around also makes it harder to identify an effect. so we also propose a specification based on a relative measure of beauty, where we identify the least attractive player among the remaining contestants with a dummy variable. the first two columns of table show estimation results comparable to column ( ) of table , for the second and third round respectively. columns ( ) to ( ) show the results for the specification including the dummy for the least attractive player for each round, including the first one. we find no evidence of discrimination based on attractiveness in the second round. gender is the best predictor of the elimination decision in the second round, with women being substantially more likely to stay in the game. we will come back on that point in the next section. in the third round, we find evidence of discrimination against the least attractive player, and the coefficient is comparable to the first round. so discrimination does not disappear with learning about player ability. table - probability of being eliminated in nd and rd round conditional logit estimates (odds ratios) ( ) ( ) ( ) ( ) ( ) round unattractive . (. ) . (. ) attractive . (. ) . (. ) least attractive . (. )** . (. ) . (. )** n. obs. all regressions control for the same variables as table , col. ( ), ** indicates significance level at percent . gender differences in discriminatory behavior we nowexplore the natureofdiscrimination in greater detail. we investigate the relation between discrimination and gender. do men care more about looks than women do? do people care more about the looks of the opposite sex? table reports separate regressions for male and female lead players. we find that women do discriminate more against the least attractive player than men do, i.e. women seem to care more about looks than men do. the difference in coefficients between male and female lead players is not significant though. columns ( ) and ( ) investigate the elimination decision when the lead and least attractive player are of opposite sex on the one hand, and of the same sex on the other hand. we find that discrimination is indeed greater when the candidates for elimination are of the opposite sex. the difference in coefficients is significant at the % level. this could explain why women discriminate more, since the least attractive player in the first round is more likely to be a man (men being on average less attractive than women). we have found almost identical results for the last selection round, where the discrimination against the least attractive player took place in games where the lead player and the least attractive player were of opposite sex (results not reported for the sake of brevity). since in the last round, most lead players are men, the discrimination plays mostly against women. overall, these results reinforce the idea that beauty has a consumption value, and that this is the main reason why people discriminate against less attractive players. table : discrimination and gender of the lead player ( st round) conditional logit estimates (odds ratios) lead player female lead player male lead player and least attractive - opposite sex lead player and least attractive - same sex ( ) ( ) ( ) ( ) fourth highest score . (. )* . (. )* . (. )** . (. ) third highest score . (. )* . (. )** . (. ) . (. )*** second highest score . (. )** . (. )*** . (. )** . (. )*** least attractive . ( . )** . (. ) . ( . )** . (. ) age . (. ) . (. ) . (. ) . (. ) gender . (. ) . (. ) . (. ) . (. ) n. obs test equality coefficients for the least attractive ( ) = ( ) p-value ( ) = ( ) p value . . notes: equality of coefficients is tested with a generalized hausman test significance levels: *: percent, **: percent, ***: percent. . costs of discrimination and the benefits of beauty we now provide an estimate of the benefits of beauty and the costs of dis- crimination. as in many other game shows, the rules are such that most contestants go home empty handed. in fact, only out of contestants (i.e. %) take any money home. moreover, even among those with pos- itive earnings, the variance is very large (the standard deviation is € , compared to the mean of € , ). these factors imply that there is a high degree of noisiness in earnings, making it a priori difficult to get statistically significant results. furthermore, given the large number of zeroes, our esti- mates are not directly comparable to estimates of the beauty premium from the labour market such as those of hamermesh and biddle ( ). column in table presents ols estimates of the determinants of log earnings. an increase in attractiveness of one standard deviation increases earnings by percentage points. despite the large standard error, this is significantly different from zero at the % level. an alternative estimate of the beauty premium is based on estimating the probability of reaching the final round. columns and provide estimates of the probability of reaching the final round with attractiveness as a continuous variable (column ) or as a discrete variable, based on the ranking of players within each show according to attractiveness (column ). the results confirm our previous findings: the two most attractive players are about twice as likely to reach the final round than the least attractive player ( % against % with a standard error of percentage points). this means that, on average, their expected earnings are twice as large. note that if we take a very conservative approach and consider the lower bound of the % confidence interval for the probability of reaching the final round, we still have a difference of percentage points in terms of probability of reaching the final round between the most and least attractive players. in this case, the estimated lower bound on the beauty premium equals %, which remains substantial. table : the beauty premium log earnings probability of reaching final round ( ) ( ) ( ) gender -. (. ) . (. ) . (. ) age -. (. ) . (. ) . (. ) attractiveness . (. )* . (. )* beauty rank (least attractive) - - beauty rank . (. ) beauty rank . (. ) beauty rank . (. )** beauty rank (most attractive) . (. )** constant . ( . ) n. obs. pseudo r-squared . . . notes: col. ( ): ols estimates allowing for a show-specific random effect; cols ( ) and ( ): conditional logit estimates (odds ratios); **: percent, *: percent. turning to the costs of discrimination, stakes are substantial on the game show. by eliminating the least attractive players instead of players who would maximize their monetary payoff, players implicitly pay a price for keeping more attractive players in the game. while we cannot directly calculate the price for keeping more attractive players in the game in the first or second round (since we do not observe the earnings of those who are eliminated), we can do a back-of-the-envelope calculation of the price they pay by eliminating the least attractive player in the third round, where we do observe perfectly the earnings of the contestants. however, the sample of observations is relatively small and the results should be taken with caution. we can identify of the episodes where the lead player eliminates the least attractive player, even though he does not have the lowest score. in these episodes, the less attractive players have earned € more on average than the player who is chosen to play the final. hence, by eliminating the least attractive players in these cases, the lead player diminishes the prize money e by € on average. notice that discrimination is directly financially costly in the final round – there are only two instances where the two low ranked players had the same score. this estimate is a lower bound since we are only looking at costs associated with discrimination in the third round, and not earlier rounds, since a precise imputation of financial costs in earlier rounds is more difficult. . gender differences it is worthwhile contrasting our results on beauty with differences between players based on gender. overall, women earn less than men, earning € on average, as compared to € . as with attractiveness, we can decompose the gender gap in earnings into different components. in terms of perfor- mance, we found that women were less likely to answer a question, and conditional on answering were no more likely to answer correctly (in round it might be that lead players expect those with a lower score to be more cooperative, for which there is evidence (in our companion paper). but this doesn’t explain why the player with a lower score is rarely chosen to play the final if he is is the least attractive player. , they are actually less likely to answer correctly). the lower performance of women could be due to the competitive character of the game show – gneezy et al. ( ) present experimental evidence showing that women perform worse in competitive environments, especially when they compete against men. despite the fact that women perform worse, they are as likely to reach the final round as men – % of the participants on the show are women, while % of the players in the final round of the game are female. one explanation for discrimination in favour of women in the selection decision is their greater cooperativeness, since women are more likely to share in the final round – % of women share against only % of men. however, this does not seem to be the explanation since women are no more likely to be selected than men in the last round (holding earnings constant), when the lead player selects the player with whom he will play the final round and where one may expect cooperativeness considerations to be dominant. it is more plausible that women are chosen despite their lower performance due to gender balance considerations (since women are relatively scarce in the show) or positive discrimination (since the selection decision is public). women’s’ greater cooperativeness widens the gender gap in earnings. in- deed, since women are much more likely to share in the final round, and since the opponent does not share more often when facing a woman, the differ- ence in take-home earnings across gender is larger than between individual scores. overall, we find no evidence of negative discrimination against women. the gender earnings gap is mainly driven by differences in performance and cooperativeness. perhaps the fact that the selection decision is public prevents gender discrimination – since gender is an objective and obvious our companion paper provides a comprehensive analysis of the determinants of the sharing decision in the final stage, and its implications for how selection decisions are made just before this. some participants explicitly mentioned "gender balance" as a consideration while making the selection decision in the second round. characteristic in contrast to attractiveness, which is more subtle. . insidious discrimination? are third parties aware of the possibility of discriminatory behavior? and if they are aware, is this knowledge conscious or sub-conscious? these ques- tions are relevant – if discrimination is not perceived by third parties, it may persist even under public scrutiny. to investigate these questions, we adopt a novel experimental procedure, by asking subjects to predict the elimination decision at the end of the first round of quiz questions. we focus on the first round since we do not want subject predictions to be influenced by learning from observing selection decisions in previous rounds. our sub- jects ( students from the university of amsterdam) were shown a trailer and given a handout, setting out the overall structure of the game show, and then shown a random sample of seven episodes. they were informed in advance of the identity of the lead player in the first round, so that they could focus on predicting the lead player’s decision. the subject was asked to assign a probability to the event that each of the other players would be chosen for elimination by the lead player. subjects were rewarded by using a quadratic scoring rule, giving them strict incentives to report their true beliefs. subjects were not informed of the actual elimination decision in any episode, so as to prevent any learning. at the end, we asked subjects a qualitative question: what, in their opinion, are the most important factors determining the elimination decision? subjects were permitted to list up to four such factors. table reports ordinary least squares estimates, where the dependent variable is the prediction of subject i regarding the elimination probability this is related but not identical to the notion of implicit discrimination (see greeen- wald et al. ( ) and bertrand and mullainathan ( )), which uses psychological tests to measure implicit bias, say against african-americans. it is worth noting that researchers have found an implicit bias against older people and the overweight. the subjects also filled out a questionnaire on their background characteristics. they earned on average € (for minutes), including a € show up fee. the full set of instructions is in the appendix. of player j. we have subjects, making predictions for four players in each of seven episodes, giving us observations. table - predictions of elimination in st round ols estimates ( ) ( ) ( ) ( ) ( ) ( ) attractiveness - . - . - . ( . )** (. )*** (. )*** dummy least attractive . . . ( . ) ( . )* ( . )* perceived confidence . . (. ) (. ) age -. -. -. -. . . (. ) (. ) (. ) (. ) (. ) (. ) gender - . - . - . - . - . - . ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** score rank th - . - . - . - . ( . )*** ( . )*** ( . )*** ( . )*** score rank d - . - . - . - . ( . )*** ( . )*** ( . )*** ( . )*** score rank d . . . . ( . )*** ( . )*** ( . )*** ( . )*** constant . . . . . . ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** n. obs. notes: standard errors are clustered by player. significance levels: *: percent, **: percent, ***: percent. our main finding is that our subjects do perceive that less attractive players are more likely to be eliminated. that is, our subjects are at least implicitly aware that discrimination on the grounds of attractiveness is likely to occur. they predict that an increase in one standard deviation in attractiveness should decrease the probability of being chosen by . per- centage points. this is substantially less than what we have estimated in subjects do not perceive any relation between a player’s confidence (as assessed by the subject) and the probability of elimination. women are predicted to be more likely to be eliminated, as are second ranked players — neither of these effects are present in the actual selection decision. the last finding appears to be due to subjects incorrectly thinking that the first ranked player may have an incentive to eliminate rivals for leadership. the actual data (the corresponding number is percentage points). inter- estingly, attractiveness is not mentioned by anyone among the two most important criteria influencing the selection decision, and only subjects list attractiveness at all. this provides suggestive evidence that discrimination is insidious, since subjects appear to be implicitly aware of its existence, but not consciously so. this is particularly noteworthy since a subject is detailing the motivations of players on the game show (rather than him- self), and would therefore have little psychological reason to lie or practice self-deception. discrimination on the basis of looks appears to meet with less social dis- approval than other forms of discrimination. following a report in new sci- entist summarizing the findings of the present paper, it was covered by news- papers in several countries including the uk and the netherlands. press coverage in the dutch newspaper “de telegraaf” triggered a large public response – within a day, readers had posted a response on the newspa- per’s website. we coded these responsesand found that of these suggested that beautiful people "deserve" to be treated better than the "ugly" – some comments were quite offensive about unattractive people. people simply acknowledged the results and gave further examples ofdiscriminatory behav- ior against ugly people. only six people explicitly condemned this kind of discriminatory behavior. furthermore, many people simply found the find- ings somewhat amusing (as did some of the articles in the popular press), rather than a matter for social concern. while its readers are unlikely to be representative, the newspaper is the largest with over , circulated copies daily. it is noteworthy that we find this response in the netherlands, a country that is well known for its progressive and liberal attitudes towards some minority groups (e.g. gay people), and one with a strong commitment to equal opportunities. our experimental findings (and the public response) raise important is- fershtman and gneezy ( ) find that experimental subjects who discriminate seem to be unaware that they do so. sues of social concern regarding the persistence of discrimination. following becker ( ), economists have focused on the extent to which the forces of competition and profit maximization eliminate discrimination. it is arguable that the social stigma associated with racial or gender discrimination is no less important a force in its elimination. to the extent that discrimination on the basis of looks or age occurs, but is either insidious or is "acceptable" even when perceived, its persistence is enhanced. . external validity one possible concern with our study is external validity, especially if the participants on the show are not representative of the population. while genuine field data on attractiveness and individual productivity might be ideal, this is hard to get, and laboratory experiments or our type of study seem to offer the best hope for disentangling the beauty premium. the producer of the show told us that no explicit criteria were used in recruit- ing participants – in particular, applicants were not required to submit a photograph, so that the producers do not seem to have been concerned with having good looking people. nor does it seem, from viewing the show, that attractive people self-select into the show. this impression is confirmed by the fact that the average rating of our participants in terms of attractive- ness is . , whereas raters were told to use as the benchmark for average attractiveness. participants also come from a variety of occupations, an advantage that compares favorably with laboratory experiments. given the lack of emphasis by the producers on attractiveness, it appears unlikely that participants’ behavior on the show reflects an internalization of such concerns. in view of our findings, it is also relevant that dutch society seems less concerned with beauty than other similar societies. spending on cosmetics and toiletries as a proportion of gdp is lower in the netherlands than most harrison and list ( ) have an extensive discussion on the external validity of game show data. other west european countries – the netherlands is (joint) fourth from the bottom in the list of the eu fifteen. the fact that we find discrimination in such a context seems particularly compelling. concluding comments to summarize, our main finding is that beauty is "only skin-deep", and has no implications for a person’s performance or their cooperativeness. nev- ertheless, it is an attribute well worth having. attractive players earn a premium, that arises from the reluctance of other players to eliminate them. this seems to reflect consumption value considerations on the part of the other players in the game. the preference for the beautiful is therefore a form of taste based discrimination. our finding is also noteworthy since participants on a tv show would be reluctant to discriminate, since their behavior is subject to public scrutiny. while discrimination on the basis of gender or race are rightly frowned upon, discrimination based on a per- son’s physical appearance is less remarked upon. indeed, it is likely that discriminators, the discriminated against and third parties are less aware of the phenomenon, so that it is, to some extent, insidious. our experimental evidence on third-party perceptions of discrimination is suggestive in this regard. we believe that discrimination on the basis of less obvious criteria such as attractiveness is likely to have qualitatively different characteristics from discrimination based on recognized categories. without overstating the external validity of our results, we believe that this raises important questions for society and social policy, and merits further research. the role of beauty is less suprising in argentina, where mobius and 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[ ] mobius, m. and t. rosenblat ( ), why beauty matters, american economic review ( ), - . [ ] mulford, m., j. orbell, c. shatto and j. stockard ( ), physical at- tractiveness, opportunity, and success in everyday exchange, ameri- can journal of sociology ( ), - . [ ] pfann, g. j. biddle, d. hamermesh and c. bosman ( ), business success and businesses’ beauty capital, economics letters ( ), - . [ ] solnick, s. and m. schweitzer ( ), the influence of physical at- tractiveness and gender on ultimatum game decisions, oganizational behavior and human decision process ( ), - . appendix: instructions [translation from dutch.] welcome! the experiment lasts for about minutes. during the experiment you will earn points that are worth money. the exact amount you earn depends on your score and can earn up to about € . none of the other participants will know what you earn and all your answers will be confidential. how you earn money you will see fragments of a television game show. you will be asked to predict the choices of contestants. the more accurate your predictions are, the higher your score and the more money you earn. only your own predictions determine your score and not the predictions made by other participants. the tv show the game show starts with candidates. in the first round, the candidates have to answer quiz questions. their score depends on the number of questions they answer correctly. at the end of the round, one candidate is eliminated by the highest-scoring candidate. you will only see the first round, and your main task is to predict who will be eliminated. you will see episodes, based on a random selection from all episodes. for background information, we also explain the rest of the game show. you will not see any of this part of the show and do not have to make any predictions about it. there at two more rounds after the first round, where again the highest scoring person has to eliminate one of the others. after these rounds, there are two candidates left. the scores of both candidates are added. this is the amount of money they will be playing for. both players simultaneously decide whether to share or grab. there are three possible situations. ( ) they both share. in this case, they both get half of the amount of money. ( ) one candidate shares and the other does not share. in this case, the one who does not share gets the whole amount. the candidate who shares gets nothing. ( ) they both do not share. in this case, nobody wins any money. before they make their share/grab decisions, candidates have the opportunity to say something to each other. instructions we start by showing the candidates introducing them- selves. you will see every candidate twice. the first time, there will be no sound and we ask you to predict the age of the candidates. the second time, you will see the candidates introducing themselves again, but with the sound. we ask you to rate the self-confidence of the candidate. you can do this on a scale from (very low self-confidence) to (very high self-confidence), taking as the average of all dutch people. after the in- troduction of the candidates, you will see the first round of quiz questions. after the end of the first round, the person with the highest score chooses which other candidate will be eliminated. at that point, we pause the show, and we will ask you to predict how likely it is that a certain candidate will be eliminated. the way we ask you to do this is as follows. the candidate with the highest score can choose one out of the four candidates. we ask you to divide pointsbetweenthese four candidates, inproportion to the likelihoodthat they will be eliminated. you can divide the points in any way you like, as long as the total equals . you should give more points to a candidate the more likely you think that this candidate will be eliminated. if you give points to one candidate, this means you are certain that this candidate will be eliminated. if you give zero points to a candidate, you are certain that this candidate will not be eliminated. [several examples were given.] to summarize, you give more points to a candidate if you think that candidate is more likely to be eliminated. in total, you allocate points over the four candidates. for any candidate, you can use any whole number from to (thus including numbers such as , , etc.). notice that the total number of points should add up to . however, you will not be penalized if the numbers you choose do not add up. if you allocate less, say only points, we will reallocate the remaining ten points in the same ratio as your original allocation. if you allocate more points (say points in total), then we will scale back the points proportionally, in this case by multiplying your allocation by / . after filling in your answer sheet we ask you to put it in the envelope on your table. after you do this, you are not permitted to take it out of the envelope. hence, you can not go back to an earlier question. your earnings at the end of the experiment, we compare your pre- dictions to the actual outcomes. you score is higher if your predictions are better. the most you can earn per prediction is points and minimum is points (you will see episodes). every point is worth c= . . for every age prediction within years of the true age, you receive c= . . your con- fidence ratings have no impact on your score. the amount you earn for the selection predictions is calculated by the formula below. this formula is chosen in such a way that it is in your interest to report your true beliefs. by reporting any other number than what you truly believe, your expected earnings are decreased. a proof of this can be requested at the end of the experiment. questions? please ensure yourself that you have understood the in- structions. if you have any questions, please raise your hand and wait until somebody comes to you. formula of your score your score is calculated in such a way that it is best for you to report your best prediction. you do not need to understand how your score is calculated in order to do well in this experiment. however, for those who want to understand the details, we explain this below. suppose you allocated pi points to candidate i, i = , , , . if candidate i is indeed selected to be eliminated, the score for your prediction is: − ( −pi/ ) − x j =i (pj/ ) . your expected score is maximized by reporting what you really believe. a proof of this can be obtained at the end of the experiment. munich personal repec archive does beauty matter in undergraduate education? deryugina, tatyana and shurchkov, olga august online at https://mpra.ub.uni-muenchen.de/ / mpra paper no. , posted feb : utc does beauty matter in undergraduate education? * tatyana deryugina, university of illinois + olga shurchkov, wellesley college ++ abstract: physically attractive individuals achieve greater success in terms of earnings and status than those who are less attractive. however, much about the mechanism behind this “beauty premium” remains unknown. we use a rich dataset to shed light on its nature at the college level. we find that students judged to be more attractive perform significantly worse on standardized tests but, conditional on test scores, are not evaluated more favorably at the point of admission. controlling for test scores, more attractive students receive marginally better grades in some cases. finally, there is substantial beauty-based sorting into areas of study and occupations. * we thank an anonymous college for providing us with student photos and academic records. specifically, we thank the college staff and administration for assistance with acquiring and understanding the data. we also thank jeff brown, kristin butcher, daniel hamermesh, robin mcknight, nolan miller, julian reif, casey rothschild, and akila weerapana for helpful comments. sizhe zhang and mehrnoush shahhosseini provided excellent research assistance. all remaining errors are our own. + department of finance, university of illinois at urbana-champaign, south sixth st., champaign, il, usa. e-mail: deryugin@illinois.edu. phone: - - . ++ department of economics, wellesley college, central st., wellesley, ma, usa. e-mail: olga.shurchkov@wellesley.edu. i. introduction in most settings, discrimination based on characteristics such as gender, age, race, and national origin is illegal. appearance-based discrimination, while not currently unlawful, has been the subject of several lawsuits in recent years. in parallel, the academic literature has documented a positive correlation between earnings and perceived attractiveness for both men and women (hamermesh and biddle, ; biddle and hamermesh, ). however, much about the mechanism behind this “beauty premium” remains unknown, including the extent to which beauty is a signal of innate or acquired ability, the extent of bias in favor of more attractive people, and the extent to which sorting plays a role. in this paper, we use a unique and rich dataset to examine the nature of the beauty premium among students at an all-women’s college. our principal goals are ( ) to test whether attractive students appear more academically capable when they begin college, as measured by their standardized test scores and admission ratings; ( ) to test whether they appear more capable when they graduate, as measured by their gpa; and ( ) to estimate the extent of beauty-based sorting into areas of study and occupations, a potentially important beauty premium mechanism. see for example yanowitz v. l’oreal usa, inc. ( ) and brice v. resch and krueger int’l, inc. (corbett, ). the importance of beauty has been studied in contexts other than the labor market. see, for example, ravina ( ) for the beauty premium in credit markets, andreoni and petrie ( ) for the beauty premium in public goods games, wilson and eckel ( ) for the beauty premium in trust games and berggren et al. ( ) for the beauty premium in electoral outcomes. to achieve these objectives, we estimate the relationships between attractiveness, standardized test scores, course grades, admissions scores, and major/career choices. we find that, even though the admissions committee does not observe applicant appearance, more attractive individuals receive lower scores on the college’s own formula for rating applicants, in this context an important measure of overall applicant quality that reflects a very wide range of student characteristics. this finding is completely explained by the fact that more attractive individuals have lower standardized test scores. specifically, a one standard deviation (s.d) increase in attractiveness is associated with scoring . s.d. lower on the math sat section, . s.d. lower on the verbal sat section, and . s.d. lower on the sat writing section. to our knowledge, our study is the first to find that attractiveness is negatively correlated with ability, as measured by these tests. once we control for math and verbal sat scores, we find no relationship between the college’s admission scores and attractiveness. in addition to showing that more attractive individuals do not appear to be more capable at the beginning of college, the absence of such a relationship implies that the negative correlation between attractiveness and sat scores among admitted students is unlikely to be driven by preferential treatment of attractive students during the admissions process. once we control for sat scores and the admission rating, our results show that more attractive women have a marginally higher overall gpa. we show that this is most likely driven by sorting into types of courses: after controlling for a rich set of course characteristics, our analysis shows no significant relationship between course-level grades and attractiveness, although estimates for some course types are marginally significant. if more attractive people are aware of the beauty premium in the labor market, they may respond by sorting into areas of study or occupations where their attractiveness generates higher returns. indeed, we find that there is substantial beauty-based selection into study areas. specifically, more attractive women are considerably less likely to major in the sciences and much more likely to major in economics. we find no corresponding selection into humanities, other social sciences, or another group of majors that we label “area studies.” overall, we conclude that the beauty premium at the undergraduate level is largely attributable to selection into study areas rather than ability or bias in favor of more attractive students. finally, we estimate the extent of beauty-based selection into various occupational categories. consistent with our results on academic major selection, we find that more attractive women are much more likely to become consultants and managers and much less likely to become scientists and technical workers (including paralegals, technical writers, technicians, and computer programmers). because previous work has shown that earnings vary substantially by major and occupation, this suggests that at least part of the beauty premium in the labor market is explained by major/occupational choice. we contribute to several streams of literature. the first assesses the relationship between attractiveness and ability; it has thus far produced mixed findings. using assortative mating for more on the relationship between earnings and academic major choice, see daymont and andrisani ( ), berger ( ), james et al. ( ), grogger and eide ( ), loury and garman ( ), loury ( ), blundell ( ), bratti and mancini ( ), arcidiacono ( ), kelly et al. ( ), arcidiacono et al.( ), andrews et al. ( ), and wiswal and zafar ( ). arguments and observed facts, kanazawa and kovar ( ) provide indirect evidence suggesting why beauty and intelligence should be positively correlated in humans. satoshi ( ) shows empirically that there is a positive association between iq test results and physical attractiveness in british and american children of both sexes. several studies have also found that body symmetry is positively correlated with cognitive performance (prokosch et al. , bates ). however, in a sample of american men, scholz and sicinski ( ) find no relationship between attractiveness and iq or high school class rank. in a laboratory experiment, mobius and rosenblat ( ) show that more attractive subjects do not perform better in a maze-solving task. in another experimental setting, deryugina and shurchkov ( ) use labor-market- relevant tasks to test for both the existence of a beauty premium and performance differentials between less and more attractive subjects. they find that there is no significant performance differential by attractiveness related to any of the tasks. to our knowledge, our study is the first to consider the relationship between attractiveness and sat scores. although standardized test scores have been shown to be correlated with broad measures of intelligence and cognitive ability (frey and detterman, ; beaujean et al., ; rohde and thompson, ; koenig et al., ), we do not claim to show that more attractive students are less intelligent. more conservatively, our results imply that, even if there is a correlation between attractiveness and fundamental intelligence, it does not translate into higher test scores. to the extent that both intelligence and effort are necessary to score well on standardized tests, it is possible that more attractive people perform worse on body symmetry has been shown to be strongly correlated with attractiveness (see e.g., rhodes et al. , rhodes ). aptitude tests despite being more intelligent. our finding suggests that, if more attractive people are more intelligent, they may invest less time and effort in human capital formation, at least along the dimensions we study (sat scores and gpa). alternatively, more attractive students may expect to be more likely to get into college, conditional on their sat scores, and may therefore rationally exert less effort preparing for standardized tests. although we cannot test expectations directly, we show that more attractive students do not receive higher admissions scores in our data. we also contribute to the broad body of literature on the beauty premium. despite numerous papers on the subject (hamermesh and biddle , biddle and hamermesh , fletcher , ravina , mocan and tekin , berggren et al. , berri et al. , scholz and sicinski , von bose ), much remains to be understood about the beauty premium. in particular, with the exceptions of scholz and sicinski ( ) and von bose ( ), neither its origins nor persistence has been studied. moreover, with the exception of fletcher ( ), the extent to which the beauty premium is driven by differences in ability has not been explicitly estimated. in a sample of high-ability law students, biddle and hamermesh ( ) find that there are no observable skill differences (including lsat scores) between more and less attractive individuals. however, von bose ( ) shows that more attractive teenagers receive higher high school gpas than less attractive ones. our findings do not definitively resolve whether more attractive individuals are more capable of academic achievement; while more attractive students perform worse on standardized tests, they are not viewed more or less favorably by admissions officers overall and at best earn marginally higher grades than their less attractive peers. however, we find strong support for another hypothesis about the beauty premium mechanism: sorting. the policy implications of our findings hinge on whether the observed sorting is efficient. it would be efficient, for example, if more attractive students are selecting into certain majors and occupations because of productivity expectations. if, on the other hand, the sorting is due to attractive students’ anticipating a pro-beauty bias in some professions then it may not be optimal from a social point of view. this line of inquiry falls outside the scope of this paper. however, it is worthwhile to note that even if the observed sorting is not socially optimal, policies designed to prevent it would most likely be impracticable. the rest of the paper is organized as follows. section ii describes our sample and data. section iii outlines the empirical strategy. section iv presents and discusses the findings. section v concludes. ii. data our dataset consists of alumnae who graduated from an anonymous women’s college between the years and . to measure attractiveness, we use pictures taken when the alumnae were first-year students. a key advantage of our data is that the pictures are not chosen by the student: all are photographed for their student id cards by campus officials. the pictures were subsequently rated by current male and female students from a college in another state. this study was conducted with irb approval. individuals had to consent to have their photographs included in the study. about , alumnae were contacted for consent. informed consent form and description of the project sent to the alumnae are available upon request. each picture was rated by at least male and female raters. we then demean the ratings to remove rater fixed effects and average them to obtain the mean attractiveness rating of each alumna. due to the large number of alumnae, not every picture was rated by the same set of raters. for additional details about the rating procedure, see appendix a. the attractiveness rating is then matched to the alumna’s academic record, which includes her major, sat scores, course-level grades, race, non-merit-based financial aid awards, international status, and scores from a quantitative reasoning (qr) test that all first-year students are required to take. like the sat, the qr test is scored blindly, without observing the test- taker’s appearance. moreover, we observe each student’s admission rating, as assigned by three or more application reviewers. with few exceptions, application reviewers do not observe the student’s appearance. at the request of the college, we use a non-disclosed linear transformation to disguise the true rating scale. finally, we have detailed characteristics for each course, including department, course level (introductory, intermediate, or advanced), total enrollment, and the gender of the instructor. starting in the fall semester of , the college implemented an anti-grade-inflation policy that capped the average grade in introductory and intermediate courses with ten or more some international applicants have toefl scores that are accompanied by a picture. in some cases, applicants are interviewed by a member of the admissions staff or by an alumna. however, the application reviewers have access only to the interviewer’s comments, which do not contain information about the applicant’s appearance. students to a b+. this policy change disproportionately affected humanities courses. if there is beauty-based selection into humanities courses, this policy change may bias our estimates. to control for the potential impacts of the anti-grade inflation policy, we identify departments that had average grades exceeding a b+ and label beginning and intermediate courses with more than ten students in those departments as “treated.” we then control for the treated indicator and its interaction with a “post-fall-semester- ” indicator in all course-level regressions. to create our course-level controls and test for sorting, we classify the courses and majors offered at the college into six categories: humanities, sciences, social sciences, area studies, economics, and other. to do this, we use a publication provided by the college, which classifies courses and majors into “humanities,” “social sciences,” “science and mathematics,” and “interdepartmental programs.” because the “interdepartmental programs” category contains a significant share of the majors, we reclassify some of them into the first three categories. in addition, we classify majors such as “south asia studies” and “german studies,” which are originally listed as interdepartmental into a new “area studies” category. we place economics in its own category because the college does not have a separate business major. thus, the students who elect to study economics may be different from students choosing other social sciences as their major. the courses and majors that do not fit into any of the above categories are classified as “other.” see appendix b for the exact classification. finally, data on occupations come from alumnae surveys and are available for slightly over half of the alumnae in our sample. we categorize occupations into ten broad categories: the full impact of the anti-grade-inflation policy has been analyzed by butcher, mcewan, and weerapana ( ). consultant/manager, administrator, art/advertising, teacher, technical, scientist, lawyer, doctor, other medical, and non-profit/government. in a few cases, the categories overlap: someone who is working in an administrative position in a non-profit would be placed in both categories, for example. there are a few alumnae reporting occupations that cannot be classified into one or more of these categories, because the occupation descriptions are either vague or very unique. although we cannot list the specific occupations due to confidentiality concerns, we provide a general list of occupations in each category in appendix b. our data are not without limitations. first, we do not observe parental income, a potentially important control. however, we do observe the amount of need-based and non-need- based loans and grants that a student receives, which we use as a proxy for parental income. we also do not observe post-college earnings. thus, we cannot test whether more attractive students in our sample also end up earning a higher salary. table presents summary statistics for the key variables in the data, broken down by whether individuals are below or above the median attractiveness rating of - . . the attractiveness rating itself ranges from - . to . and has a mean of by construction. the admissions ratings range from to , with higher ratings corresponding to a higher chance of admission. the average gpa in the sample is fairly high, ranging from . in economics to . in area studies. on average, % of the students pass the quantitative reasoning test, which is scored out of points. the average grant amount is about $ , . need-based and other loans are substantially smaller, averaging around $ , and $ , respectively. there are some significant differences between those who are above and those who are below the median attractiveness rating. more attractive students are more likely to be hispanic/latina and have about $ more in non-need-based loans. they score significantly lower on the math, verbal, and writing sections of the sat as well as on the qr test. in addition, more attractive students have lower admissions ratings, on average. finally, there are no significant differences between the two groups in terms of gpa, need-based loans and grants, or other racial categories. we later perform a formal regression analysis to test whether the differences in test scores and admissions ratings hold once controls for student characteristics are included. one potential concern is that the sample of women who consented to participate in our study may not represent all students at the college. to test for this, we compare the mean test scores, admissions ratings, and year of enrollment for the entire population of alumnae who graduated between and with those of the consenting group. the results are shown in table . overall, the consenting students have significantly higher test scores and admission ratings. they also enrolled in the college about half a year later than the general population of students, on average. because of the necessity to obtain informed consent, we cannot do anything to correct for this or test whether there is beauty-based selection. however, as long as there is no selection on the relationship between attractiveness and other outcomes, such as test scores and gpa, our analysis is valid despite the baseline differences. while we view such selection as highly unlikely, we recognize that the validity of our analysis relies on the assumption that it did not occur. we also note that the college from which we obtain data is fairly selective, as evidenced by the high average sat scores of admitted students (see table ). thus, our study complements some earlier work such as fletcher ( ), who focuses on individuals with high school diplomas only. a final concern is that, because our sample comes from a women’s college, it may not be representative of colleges as a whole. again, this would bias our results only if the beauty premium varies by college. the college from which we obtain our data draws from a pool of students and faculty similar to those of other top-tier universities and liberal arts colleges. we do not see any obvious model of sorting that would cast doubt on the generalizability of our results. moreover, our focus on women complements some earlier work that looks exclusively at men (e.g., biddle and hamermesh ; scholz and sicinski ). finally, the prior literature has found that the beauty premium exists for both men and women and is similar in magnitude. however, replicating the study in a co-educational setting should be an important validation exercise. iii. empirical framework conceptually, we might expect a positive correlation between attractiveness and academic success or, more generally, between attractiveness and some outcome of interest, for several reasons. first, attractiveness may be correlated with a particular characteristic, such as intelligence, trustworthiness, or confidence. if this characteristic is unobserved or poorly measured, omitted variable bias will result, creating a spurious correlation between beauty and the outcome of interest. in the context of academic success, if more attractive people are also more intelligent, then controlling for intelligence is crucial for isolating the effect of attractiveness itself. second, attractiveness may itself be productive in some settings. for example, more attractive solicitors may bring in more donations, justifying paying them a higher salary (landry et al. ). this mechanism is less likely to apply in a college setting, however. finally, people may be biased in favor of more attractive individuals, conditional on their characteristics and productivity. if more attractive people are aware of these channels, they may respond by exerting greater effort into their academic work and preparing for relevant tests or sorting into occupations where their attractiveness or other characteristics is more productive. unfortunately, effort in such a context is rarely readily observable. however, the richness of our data allows us to test for beauty-based sorting into both areas of study and occupations. in addition, we estimate the relationships between beauty, aptitude test scores, and course grades to shed light on the other channels through which attractiveness may operate. in theory, it is possible that a portion of attractiveness can be explained by investment rather than inherent beauty. to our knowledge, there is little work addressing the potential endogeneity of beauty and virtually no work in this area is able to fully eliminate such endogeneity concerns. we control for race and financial aid in all our regressions, which should eliminate some of the components of beauty that may be correlated with socioeconomic characteristics and thus a student’s ability to invest in appearing more attractive. our results are very robust to excluding these controls, and our summary statistics suggest that beauty is not strongly correlated with most of these characteristics. we first estimate the relationship between the attractiveness rating and admission scores. because the admissions committee does not observe applicant appearance directly, any one paper that explicitly considers investment in attractiveness is hamermesh et al. ( ), who find that there is a positive relationship between attractiveness and spending on clothing and cosmetics. correlation between attractiveness and the admission rating will be due to more attractive students differing in the quality of their recommendation letters, extracurricular activities, personal essays, and other application characteristics. 𝐴𝑑𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠𝑖 = 𝛼𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝑋𝑖′𝛾 + 𝜀𝑖 ( ) where 𝑖 represents the individual alumna and 𝐴𝑑𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠𝑖 is the average admission score assigned to her by three or more raters. the variable 𝑅𝑎𝑡𝑖𝑛𝑔𝑖 is the alumna’s attractiveness rating, and 𝑋𝑖 is a vector of student characteristics, including math and verbal sat scores, a set of race indicators, the logs of grant and loan amounts, and year-of-enrollment fixed effects. we add to the grant and loan amounts prior to taking their logs to avoid missing observations. our results are generally robust to the exclusion of controls for financial aid and race, however. in a related specification, we allow the coefficient on the attractiveness rating to vary by attractiveness quintile to test for non-linear effects. we then estimate the relationship between attractiveness and gpa, controlling for standardized test scores, the admissions rating, and student characteristics. 𝐺𝑃𝐴𝑖 = 𝛽𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝑋𝑖′𝛾 + 𝜀𝑖 ( ) where 𝐺𝑃𝐴𝑖 is the student’s grade point average on a – scale. in this case, 𝛽 may be capturing the effect of bias, sorting, or skill differences that are correlated with attractiveness but are not adequately controlled for by our ability measures. in theory, 𝛽 may also be capturing direct productivity differences associated with attractiveness itself (e.g., a more attractive model or actor may earn more money because her attractiveness is more productive). however, we think direct productivity differences are highly unlikely to be present in a college setting. in order to remove the influence of some of these factors, we also estimate the relationship between attractiveness and course-level grades. specifically, we include a rich set of course-level controls to eliminate any beauty premium driven by differential course choices. 𝐺𝑟𝑎𝑑𝑒𝑖𝑗𝑡 = 𝛽𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝐴𝑏𝑖𝑙𝑖𝑡𝑦𝑖′𝛿 + 𝑋𝑖′𝜌 + 𝑍𝑗′𝛾 + 𝜃𝑑 + 𝜇𝑎𝑡 + 𝜋𝑇𝑑 + 𝜎𝑇𝑑𝑃𝑡 + 𝜀𝑖𝑗𝑡 ( ) where 𝑖 indexes individuals, j indexes courses, and t indexes semesters. the variable 𝐺𝑟𝑎𝑑𝑒𝑖𝑗𝑡 is the course grade, measured on a – scale. the vector 𝑍𝑗 is a set of course-level characteristics, namely the gender of the instructor, total enrollment (in logs), and whether the course is a beginning, intermediate, or advanced course. finally, 𝜃𝑑 is a set of department fixed effects (e.g., english, mathematics, physics), and 𝜇𝑎𝑡 denotes course-area-by-semester fixed effects (e.g., humanities in fall , sciences in spring ). the variable 𝑇𝑑 indicates whether the department had a grade average exceeding a b+ prior to the implementation of the anti-grade-inflation policy and 𝑃𝑡 is equal to one for the fall semester of and later. standard errors in this specification are clustered by student. finally, we estimate the amount of beauty-based sorting into distinct fields of study, using a probit specification. 𝐼[𝑀𝑎𝑗𝑜𝑟 = 𝑀]𝑖 = 𝛽𝑅𝑎𝑡𝑖𝑛𝑔𝑖 + 𝑋𝑖′𝛾 + 𝜀𝑖 ( ) where 𝐼[𝑀𝑎𝑗𝑜𝑟 = 𝑀]𝑖 is an indicator equal to if a student 𝑖 is majoring in area m and otherwise. we estimate this relationship separately for five areas of study: humanities, sciences, social sciences, economics, and area studies. the classification of majors into these five areas is detailed in appendix b. we estimate an analogous equation for career choices. fall semesters in two different years are treated as different semesters. iv. results i. admission ratings and test scores our first line of inquiry is to test whether attractiveness is correlated with the admission rating of the student. this test addresses the important question as to whether more attractive applicants differ from less attractive ones prior to college attendance, at least in our sample. although the admissions committee does not observe everything about the applicant, the applications contain much more information than is available in our data, including extracurricular activities, recommendation letters, and personal essays. through these, it is possible that the admissions committee receives signals about other skills that predict college success and that may be correlated with attractiveness. because the admission rating is assigned without observing the student’s appearance, any correlation between the two will be due to beauty-based differences in application characteristics, such as those listed above, rather than bias. the results of this analysis are shown in table . all specifications include controls for the year of enrollment, the student’s race, and logs of financial aid amounts by category (need-based loans, other loans, and grants), with ’s added to avoid missing values. although the admission ratings of more attractive students are worse on average (column ), we find that this is entirely driven by sat scores. once we control for math and verbal sat scores (column ), there is no relationship between the admission rating and attractiveness. we do not control for the sat writing section score because it was not offered until , and including it would significantly reduce our sample size. the non-linear specification in column shows that the lower admission rating of more attractive applicants is driven mainly by those in the top quintile of attractiveness. however, this difference also disappears once we control for sat test scores (column ). using the estimates in column , we can reject a very small beauty premium of . or larger in admissions ratings with % confidence, which is equivalent to about . % of the mean admission rating. table rules out the possibility that attractiveness is correlated (on net) with characteristics that admissions officers can observe but we cannot. it also provides evidence that more attractive applicants are not more likely to get into college, all else remaining equal. in fact, if we do not condition on sat scores, more attractive applicants seem less likely to be admitted. the fact that more attractive applicants have worse application packages could be driven by differential ability, effort, or both. if effort is a factor, then test scores and other components of the college application, such as personal essays and extracurricular activities, are endogenously determined. as we discuss in more detail below, if effort is costly and the outside options of more attractive individuals are superior, it is possible that they will expend less effort on college preparation, even if their ability is equal to or exceeds that of their less attractive peers. one potential concern with the results in table is that it is conditional on being admitted to the college. while we do not observe the admission ratings of applicants who were not admitted, it is highly implausible that more attractive applicants are more likely to be admitted but do not have higher admission ratings conditional on getting in, for several reasons. first, the college that provided the data does not have a strict numeric cutoff for admissions. the density of admission ratings in our sample, shown in figure , confirms this. the distribution looks smooth, with no apparent discontinuity. in order for more attractive applicants to be more likely to be admitted in our case, attractiveness would have to increase the chances of the applicant’s being admitted conditional on her rating, also implying that the marginal and infra-marginal applicants would have to significantly differ from each other. second, because the admissions committee does not observe the applicant’s appearance, it is unlikely that appearance has an effect separate from the admission rating. third, we find no significant relationship between attractiveness and the admission rating when we look at students with above-median or below-median admission ratings. in addition, we explicitly test whether attractiveness moderates the importance of test scores by interacting test scores with the attractiveness rating and find that it does not. the summary statistics in table along with the results in table suggest that more attractive students perform worse on standardized tests. to test this directly, we estimate the relationship between (a) sat and qr scores and (b) attractiveness. because these tests are scored blindly, there is no concern that examiners are discriminating against or in favor of more attractive people. in other words, it is clear that attractiveness does not directly cause a higher test score in this case. rather, any correlation between test scores and attractiveness will reflect some unobserved (to us) variable, such as intelligence or effort. the results are shown in table . columns , , , and show the results of considering a simple linear relationship between attractiveness and test scores. a one s.d. increase in factors that may affect the chance of admission conditional on the admission rating include race, the applicant’s place of residence (e.g., massachusetts versus nebraska), high school quality, parental income, whether the student is the first to go to college in her family, and legacy status, among others. results are available upon request. attractiveness is associated with a . s.d. decrease in the individual’s math sat score, a . s.d. decrease in the verbal score, and a . s.d. decrease in the writing score. finally, more attractive students also score about . s.d. lower on the first-year qr score. these results are very robust to varying the set of included controls. in columns , , , and , we show the results of allowing the relationship between attractiveness and test scores to vary by attractiveness quintile. for the math sat section (column ), there is a sharp and significant drop in scores only for the top attractiveness quintile: the most attractive students score about . s.d. lower than the least attractive students. the same pattern holds for the qr test (column ). for the verbal section of the sat, the drop is more gradual, with students in the rd , th , and th quintiles performing significantly and progressively worse than students in the bottom quintile. the most attractive students score about . s.d. lower than the least attractive students. finally, we cannot detect any differences by quintile on the writing section of the sat. a potential objection to these results is that our sample consists of people who have been admitted to the college. if more attractive students have characteristics other than sat scores that are more likely to result in their being admitted, this would lead to a mechanical negative correlation between sat scores and attractiveness among the sample of admitted women. however, as we demonstrate in table , the admission scores of more attractive students are not higher, providing strong evidence against their being more likely to be admitted. moreover, restricting the sample to students with below-median admission ratings does not substantively change our results. thus, our finding of a negative correlation between attractiveness and sat scores is unlikely to be driven by this type of selection. to our knowledge, the finding that more attractive people perform worse on standardized tests is new and adds nuance to the hypothesis that more attractive individuals earn more because of some unobservable skill, such as intelligence. in contrast to our results, previous work has found that more attractive individuals attain either equal or higher test scores relative to their less attractive peers. however, with the exception of biddle and hamermesh ( ), who estimate the relationship between men’s looks and lsat scores, previous papers have used tests that aim to measure fundamental intelligence, such as iq tests. sat scores, on the other hand, are likely determined by some inherent skill and by effort, which may explain the difference between our findings and previous work. if more attractive individuals generally expect to receive preferential treatment in life or have better outside options for other reasons, they may rationally choose to exert less effort in advancing their credentials, all else remaining equal. although some of the previous work on beauty has considered beauty-driven selection, none has considered differential investment in human capital. separating differential investment from ability is beyond the scope of our data. however, our results highlight an important possibility: even if intelligence and attractiveness are positively correlated, the ability of individuals to modify their effort level may counteract or even reverse the relationship between outcomes and beauty in settings where effort matters. ii. grades the estimates in tables and demonstrate that more attractive students do not begin college with better credentials. if anything, more attractive students have lower admission ratings, driven by their lower sat scores. in addition, they subsequently score worse on a first- year qr test. a natural follow-up question is whether more attractive students end up performing better in college than their less attractive counterparts. in other words, is there evidence that the beauty advantage develops during college? we should note right away that such better performance could occur for a number of reasons: skill, bias on behalf of instructors or classmates, endogenous effort, and selection. we try to directly assess some of these factors below. throughout the analysis, we use the math and verbal sat scores as well as the admission rating as ability controls. again, we do not control for the writing sat score because it was not offered until , and including it would have significantly reduced our sample size. the benefit of including the admission rating is that it captures a broader range of skills than sat scores and it appears unaffected by attractiveness. however, our results are unchanged if we omit the admission rating from the set of controls. table shows the relationship between attractiveness and gpa, with and without controlling for test scores and the admission rating. we consider both first-year and overall gpa. while the latter is a better reflection of overall student performance, the former might be more relevant for our attractiveness measure, which reflects student appearance in their first year. our results are also generally robust to including state of high school/international student fixed effects and to not controlling for the anti-grade-inflation policy. a full set of estimates is available upon request. although we allow for the possibility that our attractiveness measure is specific to the first year, von bose ( ) finds that attractiveness is highly correlated within an individual over time. overall, there is no significant relationship between a student’s attractiveness rating and her first-year gpa, although the quintile specifications indicate that students in the second quintile have marginally lower gpas than students in the first quintile. even though the estimated beauty premium in column is significantly different from zero, the significance level is marginal and the magnitude is not large. the % upper bound for this estimate is . points or about % of the mean gpa per one standard deviation of attractiveness. the admission rating is highly predictive of gpa, demonstrating that it is a useful measure of ex-ante student ability. we next examine whether there is heterogeneity by area of study. specifically, we consider gpa separately for five major study areas: sciences, social sciences, humanities, area studies, and economics. there may be less room for instructor discretion in the sciences. thus, any difference in gpa in this area is more likely to reflect performance differences or selection rather than instructor bias. in addition, more attractive students may select into study areas in which they have a comparative advantage. table shows the results. more attractive students have a marginally higher gpa in the sciences, but there is no significant difference between more and less attractive students in any of the other study areas. however, the standard errors on the point estimates are fairly large, and we cannot rule out the possibility that the point estimates in all five areas of study are equal to each other. we next consider the relationship between course-level grades and attractiveness. because of the detailed nature of the course-level data, we are able to include many controls to eliminate the selection channel, such as course type (humanities, sciences, social sciences, area studies, for a discussion of how we classify majors and courses into study areas, see appendix b. economics, and other) and department (e.g., math, french, english). we also include course- type-by-semester fixed effects, year-of-enrollment fixed effects, race fixed effects, and financial aid amounts as controls. standard errors are clustered at the student level. the results are shown in table and indicate that there is no significant correlation between attractiveness and course-level grades. the point estimates are positive and similar in magnitude to those shown in table . the inclusion of sat scores and admissions ratings increases the magnitude of our point estimates, but they remain statistically insignificant. the results are robust to excluding the course-level controls listed above, to not controlling for the anti-grade- inflation policy, and to using only qr test scores or admission ratings as ability controls. we next test for heterogeneity in the beauty premium between small and large courses and between male and female instructors. we use two measures of course size—an indicator for below- and above-median enrollment ( or fewer v. or more students) and indicators for enrollment size quartiles. we might expect males to be more responsive to female attractiveness than females (e.g., landry et al. ). we might also expect the beauty premium to be larger in smaller courses because the appearance of individual students is easier to observe. including course fixed effects in the course-level regressions does not alter our results. however, due to the small number of observations per course (mean of , median of ), we do not use course fixed effects in our preferred specification. for space reasons, we do not show these specifications. results are available upon request. note that “large” courses have students enrolled on average, with students being the largest class size in our sample. the results are shown in table . overall, it appears that there is a modest and marginally significant beauty premium in courses taught by female instructors and in courses with above- median enrollment. there is also a marginally significant beauty premium in the smallest course size quartile ( students or fewer), with more attractive students receiving grades that are . points higher. however, as the p-values from the test of equality show, we cannot reject the hypothesis that the rating coefficients in each specification are equal to each other. moreover, the point estimate for courses with below-median enrollment is actually larger than that for courses with above-median enrollment. overall, we find little evidence for a meaningful beauty advantage for college grades: while more attractive women have a marginally higher gpa overall, they do not receive significantly higher grades once we control for a rich set of course characteristics. there is also some evidence of a marginal beauty premium in small courses and in courses taught by female instructors, but we cannot rule out the null hypothesis of no heterogeneity in these course characteristics. our interpretation of these results is that the role of attractiveness in college grades is small and economically insignificant. iii. sorting more attractive students do not begin college with better credentials than their less attractive peers. they appear to earn marginally better grades during college, all else remaining equal, but the differences largely disappear once we introduce extensive course-level controls. this suggests that there may be some beauty-based selection, another channel through which the beauty premium may occur if more attractive people specialize in areas in which they have a comparative advantage. our final goal then is to explicitly assess whether more attractive students make systematically different choices in terms of course and major selection. first, we consider the propensity of more attractive students to take courses in five main subject areas: humanities, social sciences, science, area studies, and economics. the dependent variable is the percent of courses taken by the student in that particular subject area. the results are shown in table . conditional on their test scores and admission ratings, more attractive students take . percentage points more economics courses and . percentage points fewer science courses. there is no selection into other social sciences, humanities, or area studies courses. the pattern of selection by attractiveness quintile suggests that the most attractive women select out of science courses and into economics courses almost one-for-one: women in the fourth and fifth quintile of attractiveness take . and . percentage points fewer science courses, respectively, and . and . more economics courses, respectively, than the least attractive women. thus, there is substantial beauty-based selection into course areas. a natural follow-up question is whether more attractive students are also less likely to major in sciences and more likely to major in economics. we investigate this sorting hypothesis by regressing an indicator variable for whether the student is in a particular major on her attractiveness rating and various controls, using a probit specification. some students have multiple majors and may thus appear in multiple categories. the results are shown in table . the estimated coefficients have been scaled by to make them easier to read. as expected given the results in table , more attractive students are significantly less likely to major in the sciences and significantly more likely to major in economics. the marginal effects at the mean indicate that a one s.d. increase in attractiveness is associated with a . % decrease in the probability of majoring in science and a . % increase in the probability of majoring in economics. there is no significant selection into humanities, other social sciences, or area studies majors. other majors that make up a significant fraction of the sample, namely psychology, english, and political science, likewise show no beauty-based selection (results not shown). the selection out of the sciences and into economics is again driven by the top two quintiles of attractive women, although the likelihoods appear to change monotonically with the quintile. finally, we test for beauty-based sorting into occupations, using a probit model. the estimated coefficients, scaled by , are shown in table . because occupation choice occurs shortly before or after final gpa is known, we include it as a control. however, our results are robust to not controlling for gpa. we find that more attractive women are much more likely to become consultants or managers and much less likely to enter technical or scientific fields. specifically, a one s.d. increase in attractiveness is associated with a . % increase in the probability of becoming a consultant or manager and a . % decrease in the probability of becoming a scientist or a technician. this is consistent with our earlier results on major choice. there is no significant beauty-based selection into administrative fields, art and advertising, or teaching. similarly, we find no selection into the medical or legal professions or into non-profit/government jobs (results our results are robust to considering “consultant” and “manager” separately, combining “lawyer” and “doctor,” combining “doctor” and “other medical,” and considering “art” and “advertising” separately. not shown). although we lack occupation information for almost half of the alumnae in our sample, the fact that these findings mirror those in tables and makes us more certain that they are not driven by selective reporting. moreover, the response rate in our data is similar to (and, if anything, slightly higher than) the response rate of the alumnae pool from which we draw our sample. it is worth considering whether our findings translate into earnings. although we cannot examine the relationship between earnings and attractiveness directly, we can refer to prior literature. there is some evidence that sat scores are positively correlated with post-college earnings (dale and krueger ), as is college gpa (loury , arcidiacono , hershbein ). because none of these papers considers attractiveness specifically and many restrict their sample to men, we are hesitant to argue that they extend to our setting. there is however more evidence available on the relationship between earnings and choice of college major. the existence of earnings differentials across majors is well- documented (see, e.g., daymont and andrisani , grogger and eide , loury , and arcidiacono ). overall, researchers find that students majoring in fields such as business/economics, science, and engineering generally earn more than those majoring in humanities, education, and other social sciences. these differences persist even after controlling for selection on observables (andrews et al., ). because we find that more attractive women are less likely to major in sciences but more likely to major in economics, this previous research has ambiguous implications for our findings. hershbein ( ) finds that this relationship holds only for less selective colleges. in experimental settings, both arcidiacono et al. ( ) and wiswal and zafar ( ) show that students’ perceptions of expected earnings and ability are significant predictors of major choice. likewise, berger ( ) finds that individuals choose majors that they perceive as being more likely to provide a larger stream of earnings. thus, it is likely that some of the beauty-based selection in our sample is driven by earnings expectations. alternatively, differential preferences could be driving the observed sorting in our data. for example, if more attractive individuals are also more extroverted, they may prefer to enter jobs where they are more likely to work with others, even if this does not result in higher wages. to our knowledge, however, there is no work showing the existence of a correlation between attractiveness and personality traits that would lead a more attractive person to choose one career over another, all else (including wages) remaining equal. v. conclusion the issue of beauty-based discrimination has gained increasing attention in recent years. prior literature has found that more attractive people earn more on average. however, much remains unknown about the origins and evolution of the beauty premium, including whether there are differences in academic capability between more and less attractive individuals, and the extent of bias and sorting that occurs. we contribute to the literature by considering whether there is a beauty advantage before and during college and by estimating the extent to which beauty-based sorting occurs. we find that more attractive women do not appear more academically capable at the point of college admissions. on the contrary, they receive lower admission ratings, even though the application readers never directly observe applicant appearance. this is because more attractive women receive lower sat scores. although previous researchers have found that standardized test scores are positively correlated with measures of cognitive ability (see, e.g., frey and detterman , beaujean et al. , rohde and thompson , and koenig et al. ), these findings do not necessarily contradict earlier findings that more attractive people have higher iqs. sat scores are likely to be a function of both innate ability and effort. it may be that more attractive people rationally exert less effort on the sat because the other advantages available to them make it optimal to invest fewer resources into scoring higher on the sats. testing this hypothesis is beyond the scope of this paper, but should be a worthwhile avenue for future research. we find substantial beauty-based sorting into areas of study, with more attractive women being significantly less likely to major in the sciences and much more likely to major in economics. they are also subsequently less likely to work in science-related or technical fields and more likely to become consultants, analysts, or managers. overall, our findings show that the main difference between more and less attractive people during college appears to lie not in the grades they receive but rather in the major and career choices they make. unfortunately, we cannot determine whether the observed sorting into majors is socially optimal, which is important for estimating welfare effects and deriving policy implications. however, even if inefficient sorting is present, policy tools capable of addressing it would be controversial and perhaps impossible to implement. the results suggest several directions for future research. first, reproducing the analysis with a mixed-gender group of college graduates would enhance our understanding of gender differences in the role of appearance in undergraduate education. second, studying more post- graduation outcomes, such as labor force status, earnings, and history of promotions would shed light on how the beauty premium for college graduates evolves later, after they have entered the labor market. figures and tables . . . k e rn e l d e n s it y admissions rating figure . density plot of admissions ratings table : summary statistics above-median attractiveness rating below-median attractiveness rating mean std. dev. min max obs mean std. dev. min max obs attractiveness rating . *** . - . . - . . - . - . admission rating . *** . . . . total gpa . . . . . . . humanities gpa . . . . . . social science gpa . . . . . . science gpa . . . . . . area studies gpa . . . . . . economics gpa . . . . . . math sat score *** verbal sat score *** writing sat score * qr test score . * . . . . passed qr test . . . . asian . . . . black . . . . white . . . . hispanic . ** . . . latina . ** . . . need-based loans ($) , , , , , , grants ($) , , , , other loans ($) ** , , , , stars indicate significant differences in means from the “below-median” group. significance levels: * percent, ** percent, *** percent. social science gpa excludes economics. table : difference between the general student population and those giving consent ( ) ( ) ( ) ( ) ( ) ( ) math sat verbal sat writing sat qr test score admission rating year enrolled all students . . consenting minus all . *** . *** . *** . *** . *** . *** observations , , , , , , significance levels: * percent, ** percent, *** percent. table : attractiveness and admission ratings ( ) ( ) ( ) ( ) attractiveness rating - . *** - . ( . ) ( . ) attractiveness quintile = . . ( . ) ( . ) attractiveness quintile = . . ( . ) ( . ) attractiveness quintile = - . - . ( . ) ( . ) top attractiveness quintile - . *** - . ( . ) ( . ) math sat score . *** . *** ( . ) ( . ) verbal sat score . *** . *** ( . ) ( . ) dep. var. mean . . . . observations r-squared . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include year of enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : attractiveness and test scores ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) math sat verbal sat writing sat qr test attractiveness rating - . *** - . *** - . * - . ** ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . - . . ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . ** - . - . ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . *** - . - . ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . *** - . *** - . - . ** ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . observations r-squared . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include year-of-enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : attractiveness and gpa ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) first year gpa overall gpa attractiveness rating - . . . . * ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . * - . * - . ** - . ** ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . . - . - . ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . . ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . . - . . ( . ) ( . ) ( . ) ( . ) math sat score . ** . ** . . ( . ) ( . ) ( . ) ( . ) verbal sat score . - . . . ( . ) ( . ) ( . ) ( . ) admission rating . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . observations r-squared . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include year-of- enrollment fixed effects, race fixed effects, and financial aid amounts. table : attractiveness and gpa by area of study ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) sciences social sciences humanities area studies economics attractiveness rating . * . . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . . . - . . ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile . . . . - . ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . *** . *** . . . . . . . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . - . . . - . - . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating . *** . *** . *** . *** . *** . *** . ** . ** . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . observations r-squared . . . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. all specifications include year and race fixed effects, as well as financial aid controls and controls for math sats, verbal sats, and admission rating. table : attractiveness and course-level grades ( ) ( ) ( ) ( ) ( ) ( ) attractiveness rating . . . ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . ( . ) ( . ) ( . ) attractiveness quintile = - . . . ( . ) ( . ) ( . ) top attractiveness quintile - . . . ( . ) ( . ) ( . ) math sat score . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) verbal sat score . *** . *** . . ( . ) ( . ) ( . ) ( . ) admission rating . *** . *** ( . ) ( . ) dep. var. mean . . . . . . observations , , , , , , r-squared . . . . . . standard errors clustered by student in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include fixed effects for: department, course level, semester-by-course type, year of enrollment, and race. in addition, controls include the gender of the instructor, total course enrollment (log), and the amount of financial aid received by the student. course level is either beginning, intermediate, or advanced. course type is humanities, social sciences, economics, area studies, sciences, or other. department fixed effects represent a specific department code, such as english, economics, physics, etc. table : attractiveness and course-level grades heterogeneity ( ) ( ) ( ) ( ) ( ) ( ) female prof x rating . . * ( . ) ( . ) male prof x rating - . . ( . ) ( . ) below median size x rating . . ( . ) ( . ) above median size x rating . . * ( . ) ( . ) bottom quartile x rating . . * ( . ) ( . ) nd quartile x rating . . ( . ) ( . ) rd quartile x rating . . ( . ) ( . ) top quartile x rating - . . ( . ) ( . ) ability controls y y y test of equality p-value . . . . st = nd quartile p-value . . st = rd quartile p-value . . st = th quartile p-value . . dep. var. mean . . . . . . observations , , , , , , r-squared . . . . . . standard errors clustered by student in parentheses. significance levels: * percent, ** percent, *** percent. all regressions include fixed effects for: department, course level, semester-by-course type, year of enrollment, and race. in addition, controls include the gender of the instructor, total course enrollment (log), and the amount of financial aid received by the student. course level is either beginning, intermediate, or advanced. course type is humanities, social sciences, economics, area studies, sciences, or other. department fixed effects represent a specific department code, such as english, economics, physics, etc. table : selection into subject areas ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) sciences social science humanities area studies economics attractiveness rating - . *** . - . - . . *** ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . ** . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . * - . . - . . ** ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . ** - . . . . *** ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . *** . *** - . *** - . *** - . *** - . *** . ** . ** . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . *** - . ** . . . *** . *** . . - . *** - . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating . * . * - . - . - . - . - . - . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . observations r-squared . . . . . . . . . . robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. dependent variable is fraction of courses taken in a particular subject area. all regressions include year of enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : selection into majors ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) sciences social science humanities area studies economics attractiveness rating - . *** . - . . . *** ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . * . . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . - . - . - . . ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = - . *** - . . . . * ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile - . *** . - . . . ** ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . *** . *** - . *** - . *** - . *** - . *** - . - . . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . ** - . ** . . . . . . - . *** - . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating . . - . - . - . - . . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . observations robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. regression specification is a probit. dependent variable is an indicator for majoring in a given subject area. all regressions include year-of-enrollment and race fixed effects, as well as controls for the amount of financial aid received. table : attractiveness and career choice ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) consultant/manager administrator art/advertising teacher technical scientist attractiveness rating . *** . - . - . - . ** - . ** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . ** - . - . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . - . - . . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) attractiveness quintile = . - . . - . - . ** - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) top attractiveness quintile . * - . - . - . - . - . * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) math sat score . ** . ** - . ** - . ** - . * - . * - . - . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) verbal sat score - . - . - . - . . . . . . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) admission rating - . - . . . - . - . . . - . - . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) gpa . . - . - . . . . . . . - . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) dep. var. mean . . . . . . . . . . . . observations robust standard errors in parentheses. significance levels: * percent, ** percent, *** percent. regression specification is a probit. dependent variable is an indicator for reporting an occupation in the given area. all regressions include year of enrollment and race fixed effects, as well as controls for the amount of financial aid received. references andreoni, james and ragan petrie. . “beauty, gender and stereotypes: evidence from laboratory experiments.” journal of economic psychology, ( ): – . andrews, rodney j, jing li, and michael f. lovenheim. . “quantile treatment effects of college quality on earnings: evidence from administrative data in texas.” nber working paper . arcidiacono, peter. . “ability sorting and the returns to college major.” journal of econometrics, : – . arcidiacono, peter, v. joseph hotz, and songman kang, . “modeling college major choice using elicited measures of expectations and counterfactuals.” journal of econometrics, ( ): - . bates, timothy c. . “fluctuating asymmetry and intelligence.” intelligence, : – . beaujean, a. alexander, michael w. firmin, andrew j. knoop, jared d. michonski, theodore p. berry, and ruth e. lowrie. . “validation of the frey and detterman ( ) iq prediction equations using the reynolds intellectual assessment scales.” personality and individual differences, ( ): - . berger, mark c. . “predicted future earnings and choice of college major.” industrial and labor relations review, ( ): – . berggren n., h. jordahl, and p. poutvaara. . 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"judging a book by its cover: beauty and expectations in a trust game." political research quarterly, ( ): - . wiswal, matthew and basit zafar, . “determinants of college major choice: identification using an information experiment.” working paper. appendix a. rating procedure and instructions all alumna pictures were rated by at least female and male raters. raters were students at a college in a different state and were pre-screened to ensure that they were not familiar with students from the college of interest. raters were shown pictures of each student and asked to rate her physical appearance on a – point scale. five of the numbers had descriptions describing the level of attractiveness corresponding to that number (see experimental instructions on the next page). raters were instructed to choose the numbers without descriptions if they felt the student’s appearance fell between the two descriptions. each rater was shown four sets of about photos. the order of the photos within each set was randomized for each rater. in early stages of the experiment, we compared the mean and standard deviation of ratings across photo sets to see if having subjects rate pictures led to fatigue. there was no significant difference in either the mean or standard deviation of ratings for earlier and later sets, which led us to conclude that pictures was not an excessive number. we did not use data from three raters who chose ’s % or more of the time. the “ ” option was the closest to the “next” button. thus, these subjects were most likely trying to complete the experiment as quickly as possible. you are about to participate in an experiment involving the perception of appearance. once the experiment begins, you will see a photograph of an individual along with the following prompt: choose the number that best corresponds to your evaluation. choose the numbers without descriptive text ( , , , , and ) if you feel the person’s appearance falls between the descriptions found in the adjacent numbers. after you have chosen a number, click “next.” you will then see another photograph and be asked to repeat the procedure. continue selecting the number you feel best reflects your assessment of the individual’s appearance until you are told to stop. instructions for the experiment rate this person's physical appearance using the following scale: strikingly handsome or beautiful good-looking (above average for age and sex) average looks for age and sex quite plain (below average for age and sex) homely appendix b. major, course, and occupation classifications major and course classifications humanities social sciences art - history africana studies art - studio anthropology chinese environmental studies cinema and media studies history classical civilization international relations comparative literature peace & justice studies english philosophy french political science german psychology greek religion italian studies sociology japanese women’s studies latin women’s and gender studies media arts and sciences medieval/renaissance studies music russian spanish theater studies area studies science american studies astronomy chinese studies astrophysics classical & nr eastern biological chemistry east asian studies biological sciences french cultural studies chemical physics german studies chemistry jewish studies cognitive & linguistic sciences latin american studies computer science middle eastern studies geology russian area studies geosciences south asia studies mathematics neuroscience physics other economics archeology economics architecture education engineering linguistics military science physical education urban studies occupation classifications advertising/art scientist advertising/marketing researcher (except economics) political (non-government employee) earth sciences design chemistry non-technical writing biology architect astronomy performing physics publishing/broadcasting mathematics museums/galleries engineering technician consultant/manager technician manager paralegal/legal assistant consultant technical writer analysis computer-related work finance economist administrator/retail lawyer administrative/human resources lawyer retail teacher physician elementary, middle, high school physician/doctor dentist psychologist other medical nurse health worker physical therapist veterinarian does beauty matter in undergraduate education? f* tatyana deryugina, university of illinois f+ olga shurchkov, wellesley college f++ i. introduction ii. data iii. empirical framework iv. results i. admission ratings and test scores ii. grades iii. sorting v. conclusion figures and tables references appendix a. rating procedure and instructions appendix b. major, course, and occupation classifications major and course classifications occupation classifications essential and skin-deep: the beauty of epidermal lipoxygenasesâ™¦ papers of the week essential and skin-deep: the beauty of epidermal lipoxygenases� � see referenced article, j. biol. chem. , , – lipoxygenases mediate the effect of essential fatty acid in skin barrier formation. a proposed role in releasing omega-hydroxyceramide for construction of the corneocyte lipid envelope as defined nearly a century ago, dietary deficiencies in polyunsaturated fatty acids (pufas) are hallmarked by the appearance of dry, scaly skin. two epidermis-specific enzymes that act on pufas are the lipoxygenases alox b and aloxe , and just within the past decade, a deficiency in either of these has been associated with disease states characterized by dry, scaly skin. the biochemical mysteries that connect these two observations and explain lipoxygenase functionality in skin hydration have remained obscure, but in their jbc paper of the week, zheng et al. elucidate a conceptual framework for understanding how alox b and aloxe function concertedly to maintain the epidermal water barrier. through high-resolution spec- troscopic methods, the authors show that the enzymes together oxidize the pufa moiety of a pufa-ceramide linkage (i.e. the linoleoyl moiety of o-linoleoyl-�-hydroxyceramides). more- over, the sequential oxygenase reactions preface the hydrolytic release of the oxidized linoleoyl moiety from the ceramide component, the latter of which ultimately participates in the microarchitecture of the epidermal water barrier. doi . /jbc.p . e ooo o lamellar lipids outside cross-linked proteins inside cornified envelope (ce) o o oh glc-o early stage of barrier formation fused lamellar lipids covalent linkage couples cle to ce and seals barrier late stages of barrier formation covalent coupling to protein o hn oh ho o o hn oh ho o o hn oh ho o r-lox elox “oxygen signal” hydrolysis of oxidized linoleate o hn oh ho o oh hn oh ho o oxidation of linoleate in ceramide cle hn o o oh skin barrier formation: essential fatty acids linked to essential enzyme activities. this is an open access article under the cc by license. http://creativecommons.org/licenses/by/ . / essential and skin-deep: the beauty of epidermal lipoxygenases♦ www.sciencemag.org science vol january a p p l i e d p h y s i c s transistors turn on the light the field of optoelectronics usually requires the integration of separate devices with optical and electronic functionalities. the extra masking, patterning, and wiring processes involved in the integration add significantly to the fabrication time and therefore to the cost of the end product. furthermore, as these “separates” need to talk to each other, there may also be a re- duction in the device perform- ance. feng et al. have fabricated a heterojunction bipolar transis- tor based on an ingap/gaas structure that combines both functions—three-terminal elec- tronic control and optical func- tion—in one device. they demonstrate that as their tran- sistor is turned on, it also emits light as the injected carriers re- combine in the vicinity of the base layer contact. by modulat- ing the current of the base layer contact, they also demonstrate the ability to switch the light emission at rates up to mhz. although this modulation rate is rather slow, but perfectly suf- ficient for display purposes, present wide-bandgap hetero- junction transistors can now achieve switching rates of ghz, indicating a possible use for these light-emitting transis- tors in optical communication networks. — iso appl. phys. lett. , ( ). m i c r o b i o l o g y vaccinating cattle contaminated food—hamburg- ers are a notorious exam- ple—is the primary source of dangerous enteric infec- tions by escherichia coli o :h (ehec), which in humans can cause bloody diarrhea and, in some cas- es, hemolytic uremic syn- drome. because ehec has been found in almost % of beef carcasses in north america, an important commercial aim is to re- duce exposure to the bacteria by reducing the extent to which ehec colonizes the cattle intestine. ehec virulence is attributed to the ability to secrete deter- minants, via a type iii secretion system, that include the ad- hesins tir and espa and the pore-forming protein espb, which together promote bacte- rial attachment to host cells. potter et al. have chosen these molecules as constituents of a trial vaccine for calves. the trial was carried out under commer- cial livestock-rearing conditions, and the trial animals were then exposed to the o :h strain. vaccination increased specific antibody titer -fold after a single booster and reduced the duration and quantity of ehec shedding. as well as being eco- nomical to prepare, a livestock vaccine must be effective enough to minimize the num- ber of times an animal has to be handled, which would add to rearing cost. plus, developing a livestock vaccine might be a useful route to a human vac- cine against ehec. — ca vaccine , ( ). c h e m i s t r y super switcher the extent to which water can wet a surface is dependent on a number of factors, including the chemistry and the roughness of the surface. various methods have been used to change the extent of wetting dynamically, but they cover only a limited range of water contact angles. sun et al. show that they can reversibly switch a surface from being superhydrophilic to being superhydrophobic with a very small change in temperature. on its own, poly(n-isopropy- lacrylamide) will switch from being hydrophilic to being mild- ly hydrophobic when the tem- perature is raised from ° to °c. at the lower tempera- tures, the c=o and n-h groups are partnered by water mole- cules, and intermolecular hydro- gen bonding dominates; when the temperature is raised, in- tramolecular hydrogen bonding takes over, ejecting the water molecules, and the chains adopt a more compact form. the authors enhanced this transition by depositing the polymer onto patterned sili- con substrates. as the pat- tern size was decreased (fin- er grooves), they observed an increase in the range of contact angles achieved on switching. detailed investi- editors’ choice c l i m a t e s c i e n c e testing the waters iron fertilization of the surface ocean layer has been considered as a possible strategy for reduc- ing the burden of atmospheric co ; this would mitigate green- house gas buildup and global warming. the idea is that co would be removed from the at- mosphere by sequestering it as new ocean production in “high nutrient—low chlorophyll” re- gions, where biological produc- tion is limited by the scarcity of iron. this approach might have other consequences, however, including the increased production and atmospheric concentration of n o, another powerful greenhouse gas. using a suite of three-dimensional, coupled physical-biogeochemical models and an oceanic n o cycle module, jin and gruber assess how excess production caused by iron fertilization would affect atmospheric n o. they find that additional n o production could offset % of the effect of co removal when fertilization of limited duration and size is undertaken in the tropics, and that small- er but still substantial offsets can be expected when fertilization is undertaken elsewhere over longer periods. these results indicate that ocean fertilization with iron, in order to reduce atmos- pheric co , may be less efficacious than has been hoped. — hjs geophys. res. lett. , . / gl ( ). h i g h l i g h t s o f t h e r e c e n t l i t e r a t u r e edited by gilbert chin fe diatom foraminifera co n o fe fe compensatory greenhouse gas fluxes. c r e d it s : (l e f t ) d e b r a j . m o r g e n e g g /s c ie n c e ; (r ig h t ) s . g r u e n h e id , c . r o s e n b e r g e r ,a n d b . b . f in l a y continued on page ehec adhering to human intestinal cells. ehec adhering to human intestinal cells. o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/ gation of the substrate showed a large frac- tion of irregular nanoparticles produced by sputtering from neighboring regions and thus a very large surface area. — msl angew. chem. int. ed. , ( ). b i o p h y s i c s small is beautiful although many biologists are interested in phenome- na operating on micro- meter-to-nanometer scales, they often rely on their physical science colleagues in adapting existing technology to new us- es: for example, x- ray crystallography for structure deter- mination of macromolecules and atomic force microscopy for probing single bio- molecules. alivisatos reviews the recent crossover of quantum dots— clusters of roughly a few thousand inor- ganic atoms with favorable properties for biological imaging (intense stable fluores- cence in the visible region). lidke et al. illustrate their use with epidermal growth fac- tor—quantum dot (egf-qd) conjugates. egf binds to members of the erbb family of receptor tyrosine kinases, and inappro- priate expression of these receptors is im- plicated in some types of cancer. fortunately, egf-qds also bind to these receptors, making it feasible to monitor endocytosis and intracellular trafficking of the growth factor. coupling the use of these ligands to expression of various fluo- rescent pairs of erbb receptors suggested that heterodimerization of erbb and b (but not erbb and b ) is triggered by the interaction with egf. — gjc nature biotechnol. , ; . /nbt ( ). g e o c h e m i s t r y selenospheres selenium is an important biological trace element: an essential part of some metallo- enzymes and a nutrient at low concentrations, but a pollutant and a toxic species at high lev- els. elemental selenium is used in many electronics applica- tions, and recent efforts have focused on growing microscopic selenium wires and crystals with advantageous characteris- tics and optical properties for use in devices. oremland et al. show that phylogenetically distinct groups of bacteria that live in a range of environments process selenium in ways that may bear on these aspects of selenium chemistry. these bacte- ria reduce selenium oxyanions in order to grow and deposit elemental selenium exter- nally. imaging and spectroscopy show that the selenium is precipitated as uniform crystalline nanospheres about nm in diameter. surprisingly, different bacteria produce spheres with different arrange- ments of the selenium atoms and hence different optical properties. — bh appl. environ. microbiol. , ( ). b i o m e d i c i n e the lo road to atherosclerosis lipoxygenases (los) are a family of en- zymes that are attracting attention be- cause of their role in the biosynthesis of lipids that mediate inflammatory and aller- gic reactions. inhibitors of these enzymes are already in clinical use for treatment of asthma. because lipid-mediated inflamma- tory circuits are also etiologic factors in atherosclerosis, dwyer et al. investigated whether genetically determined variation in los might contribute to vascular dis- ease. in a pilot study of healthy indi- viduals, they found that two variant alleles of the gene encoding -lo were associated with an increase in carotid artery intima- media thickness, an established indicator of systemic atherosclerosis. notably, the ef- fects of these variant alleles appeared to be modified by dietary intake of certain types of fatty acids, such as those in ma- rine fish. this study and a recent mouse analysis linking a different lo gene to os- teoporosis (see reports, january , p. ) broaden the scope of disorders that are potentially treatable with drugs targeting these enzymes. — pak n. engl. j. med. , ( ). www.sciencemag.org science vol january continued from editors’ choice retrograde transport of egf-qds (red) in a filopodium (green). c r e d it s : l id k e e t a l. , n a t u r e b io t e c h n o l. . /n b t ( ) o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/ small is beautiful gilbert j. chin doi: . /science. . . a ( ), . science article tools http://science.sciencemag.org/content/ / / . content related file:/content/sci/ / /twil.full permissions http://www.sciencemag.org/help/reprints-and-permissions terms of serviceuse of this article is subject to the is a registered trademark of aaas.sciencescience, new york avenue nw, washington, dc . the title (print issn - ; online issn - ) is published by the american association for the advancement ofscience © american association for the advancement of science o n a p ril , h ttp ://scie n ce .scie n ce m a g .o rg / d o w n lo a d e d fro m http://science.sciencemag.org/content/ / / . http://www.sciencemag.org/help/reprints-and-permissions http://www.sciencemag.org/about/terms-service http://science.sciencemag.org/ swp .dvi beauty and the sources of discrimination∗ michèle belot†, v. bhaskar‡, & jeroen van de ven§ september , abstract we analyze behavior on a tv game show where players’ earnings depend upon several factors. attractive players fare better than less at- tractive ones, even though they perform no differently on every dimen- sion. they also exhibit and engender the same degree of cooperative- ness. nevertheless, they are substantially less likely to be eliminated by their peers, even when this is costly. our results suggest that discrimi- nation arises due to consumption value considerations. we investigate third party perceptions of discrimination by asking experimental sub- jects to predict elimination decisions. subjects’ predictions implicitly assign a role for attractiveness but underestimate its magnitude. keywords: discrimination, beauty premium. jel classification numbers: c , d , j , j . ∗we are grateful to dan hamermesh, gordon kemp, two anonymous referees and the editor (jörn-steffen pischke) for very useful comments and suggestions. we also thank seminar/conference participants at university college dublin, university of st andrews, university of amsterdam, university of essex (iser), the gate conference in lyon ( ) and the espe conference in chicago ( ). a special thanks to debbie hall for research assistance. †department of economics and institute for social and economic research (iser), university of essex, mbelot@essex.ac.uk. ‡department of economics, university college london, v.bhaskar@ucl.ac.uk. §department of economics and amsterdam centre for law and economics (acle), university of amsterdam. j.vandeven@uva.nl. introduction in a surprising and influential paper, hamermesh and biddle ( ) found a substantial beauty premium in the labor market, of the order of %. while there are several competing explanations for this premium, its source remains an open question. attractiveness may be correlated with unob- servable productive attributes such as health, education or other types of human capital. attractive people may be more confident, thus enhancing their social skills in the workplace. there may also be an element of reverse causality – individuals who fare well in the labor market may have both the ability and incentive (via greater self esteem) to invest in looking good. perhaps the simplest (and least palatable) explanation is that beauty has "consumption-value", either to the customers of the firm, fellow employees, or the boss. the beauty premium in this case is a form of taste-based dis- crimination, as discussed in becker ( ). while anecdotal evidence on the importance of consumption value considerations in the hiring of air hostesses or waitresses certainly exists, the question remains whether this is a more general phenomenon. more generally, as the literature on racial/gender discrimination shows (see altonji and blank, ; heckman, ), estab- lishing discrimination and distinguishing between statistical and taste-based discrimination is difficult. the main contribution of this paper is to disentangle the sources of advantage to attractive people. we do this in the context of a tv game show where participants are engaged in a variety of "tasks". we can ask: are attractive people more productive, and do they exhibit greater confidence? are they more cooperative or do they engender cooperation? are they more likely to be chosen by their peers when a selection decision has to be made? we are able to answer these questions since the game show has a rich structure, with players being involved in a number of different tasks see mobius and rosenblat ( ) for experimental evidence in favor of this hypothesis. biddle and hamermesh ( ) address the reverse causality problem in a study on lawyers by using a measure of beauty based on photographs taken at law school. and decisions. it takes place over three rounds, in which players accumulate "earnings" by answering quiz questions, and their earnings depend on the accuracy of their answers, on how quickly they press the buzzer and also on their "investment decisions". earnings therefore depend upon ability as well as a player’s confidence. this allows us to study the effect of attractiveness as well as other player characteristics upon performance. at the end of each round, the lead player – the one with the highest earnings – decides which one of the remaining players to eliminate. this allows us to study the role of attractiveness and gender (in addition to performance) upon the selection decision. after the final round, when only two players remain, they play a prisoner’s dilemma game, allowing us to study the relation between beauty and cooperativeness. the median stake in this prisoner’s dilemma game is € , , so that the monetary consequences of players’ decisions are substantial. we find that attractive players fare significantly better than unattractive ones. players can only make positive earnings by making it to the final prisoner’s dilemma stage of the game show. only % of the least attractive players make it to the final round, as against % of the most attractive ones. this difference cannot be attributed to any aspect of performance – attractive players fare no differently from unattractive ones in answering questions or in investment behavior. they are no more likely to cooperate in the final stage, and opponents also behave no differently vis-a-vis them. nevertheless, when one player has to be eliminated by the lead player, the least attractive player of a show is significantly more likely to be chosen. our results support a "consumption value" basis for discrimination. dis- criminating in favor of attractive players is not simply used as a tie-breaking rule between otherwise similar players. unattractive players are more likely to be eliminated even when they have a higher score than others. this is costly to the lead player, implying an adverse selection in terms of earning potential. we estimate that the average cost to lead players from discrimi- nation in the final round alone amounts to about € , i.e. about percent of the median stake. this is an underestimate of the overall costs of dis- crimination over all the rounds. in view of our finding that attractiveness is unrelated to cooperativeness in the prisoner’s dilemma, this cost has no offsetting financial benefit. it is noteworthy that we find discrimination against the unattractive on a tv show, where each player’s performance is clear-cut and where the lead player’s decision is subject to public scrutiny. other studies using tv shows (levitt ( ), antonovics et al. ( ) and list ( )) find no evidence of discrimination on the basis of race, gender or ethnic background, but some weak evidence of discrimination against older players (these papers do not examine the role of beauty). discrimination on the basis of looks may not be so imprinted in social consciousness as racial or gender discrimination, so that people are not so aware of the possibility of discrimination, i.e. such discrimination may be insidious. to investigate third party perceptions of discrimination, we ran an experiment where subjects watched the game show and had to predict elimination decisions. our subjects predict that attractive players are less likely to be eliminated, although they substantially underestimate the magnitude of this effect. we also ask our subjects to list qualitative factors that influence elimination decisions, and find that very few subjects mention attractiveness. thus third parties appear to be aware of the possibility of discrimination subconsciously rather than consciously. we also present suggestive evidence that discrimination on the basis of looks appears to entail less social opprobrium than racial discrimination, making it easier to survive and persist. the remainder of this paper is organized as follows. section reviews the related literature. section describes the game show and our construction of the measure of attractiveness. section analyzes behavior on the game show, in terms of performance and cooperation. section studies the selec- insidious is defined as "working or spreading harmfully in a subtle or stealthy manner" (answers.com). tion decisions by lead players and establishes that attractive players benefit in this context. we also examine gender differences and find significant dif- ferences in performance between men and women, with the result that there does not appear to be any evidence of discrimination against women. this section also presents our experimental findings on third party perceptions of discrimination. the final section concludes. related research following the work of hamermesh and biddle ( ), who find a beauty premium in the labor market in a variety of occupations, several papers have replicated its findings, and also attempted to disentangle the components of the premium. biddle and hamermesh ( ) analyze a sample of lawyers, and find a premium irrespective of their area of expertise, including the self- employed. they argue that the most plausible explanation is taste-based discrimination by clients. mocan and tekin ( ) find that unattractive people sort into criminal activity due to the existence of a beauty premium on the legal labor market. there are two difficulties with field studies. first, data on attractiveness is rarely available. second, it is difficult to disentangle attractiveness from ability, since productivity is rarely observable. this makes it hard to estab- lish whether the beauty premium is due to productivity or discrimination. such productivity effects are sometimes present. landry et al. ( ) find that attractive female solicitors are more productive fund-raisers. pfann et al. ( ) study a sample of dutch advertising firms and find that those with better looking executives have higher revenues – this is particularly pertinent for our paper, since it demonstrates that beauty plays a role in the netherlands. laboratory experiments are better suited to disentangling the sources of the beauty premium, since they can be designed for this purpose. mobius and rosenblat ( ) take this approach, using university students in ar- gentina. they find that the beauty premium appears to be partly due to the fact that attractive people are more confident. since our results differ from theirs — we find that beauty is unrelated to actual confidence, as re- flected in behavior, although it is correlated with third party perceptions of confidence – we discuss their paper in more detail in section . . , while presenting these findings. benjamin and shapiro ( ) find that experi- mental subjects are able to predict the electoral fortunes of candidates on the basis of -second silent video clips, suggesting that attractiveness (or charisma) plays an important political role as well. there is a large literature on discrimination on the basis of race or gender (see altonji and blank ( ) for a survey). one difficulty in labor market studies is in establishing discrimination – see, for example, the criticisms of heckman ( ). bertrand and mullainathan ( ) conduct an field ex- periment which circumvents these criticisms and shows convincing evidence of employer discrimination against african-american names. however, it remains an open issue whether such discrimination is statistical or taste based, since employee performance on the job is not observable. description of the data . the game show we use data from all episodes of the game show ‘does (s)he share or not?’, broadcast in the netherlands in , with contestants in total. in the preliminary stage of the game, six prospective players choose their initial capital, a number between one and . the player with the highest choice is eliminated, leaving five players for the game proper. figure shows the structure of the game. the game then proceeds with three quiz rounds, where players accumu- the name of the show in dutch is ‘deelt ie ’t of deelt ie ’t niet?’. the format of this preliminary elimination stage was slightly different in the first few episodes. pre-stage (initial capital) investment decision regular q.’s regular q.’s investment and play bonus q. elimination decision quiz round quiz round prisoner’s dilemma stage quiz rounds details quiz round figure : timeline of the game show. late earnings. every round has ten regular questions and a bonus question. players first choose how much of their capital to "invest" in answering each question (yi). whoever presses the buzzer first gets to answer. a correct answer yields yi, while an incorrect answer earns −yi. a player whose cap- ital falls below his or her chosen investment may not answer any further questions. each round ends with a bonus question, where players compete for the right to answer the question by choosing new investments. at the end of the round, the player with the highest score at that point – the lead player henceforth – must select one of the remaining other players for elimination. an eliminated player has no further role in the game and loses all of his or her earnings. the show then proceeds to the next round, where all players start with a capital that equals the earnings of the lead player in the previous round. the last two remaining players play a prisoner’s dilemma game. let e denote the total prize money, which equals the sum of earnings of the two finalists. the finalists simultaneously decide whether to share or to grab. the monetary payoffs, as depicted in table , correspond to a generalized prisoner’s dilemma, where grab is a weakly dominant strategy. table - monetary payoffs share grab share e, e , e grab e, , table presents summary statistics of the game show and the players. the total prize at stake varies between € and € , , with a median value of € , . players choose to share % of the time in the final round. the age of players varies between and with an average of . . about a third of players is women. of the third of the players who report their occupation, one-third is student, while the others are drawn from all the important sectors (at the two-digit classification level), including trade, information technology, education, financial services and health. table - summary statistics, game show players mean min max mean age (years) (n = ) . percentage women (n = ) . - - prize (€) (n = ) , percentage sharing (n = ) . - - . measure of beauty hamermesh and biddle ( ) argue that there are consistent standards of beauty within and even across cultures, so that subjective evaluations of attractiveness include a "common component". our goal is to see how this common component affects performance on the game show. to this end, each of the participants on the game show were rated on a scale from (very unattractive) to (very attractive) by approximately raters, balanced by gender. raters were recruited in public spaces to obtain a representative sample of the adult population. raters were on average . years old, which is close to the average age of game show participants, years. we recruited raters, and each rated participants. this was based on watching short silent video fragments of the game show in which a player introduced him or herself. we ensured that all five players on any show were rated these are considerable sums given that the median disposable monthly income of a full-time employed person in the netherlands was about € , in (statistics netherlands, available at www.cbs.nl). by the same set of raters, while varying the order in which the shows were presented. about one-third of the raters were non-dutch and could not be familiar with the show, and only a small minority of the dutch raters indicated that they had seen any episode of the show. given this, and the fact that the game show was broadcast five years prior to the ratings, our results are not distorted due to familiarity with the faces. our measure of attractiveness is the average of the independent ratings (across raters) for each player. there is a high degree of concurrence on at- tractiveness across raters. across sub-samples of raters who rated the same sample of players, the cronbach’s alpha ranged from . to . , showing high agreement. table reports summary statistics of the ratings. raters were told to use the benchmark average attractiveness in the population at . somewhat surprisingly, the average rating across participants is . , i.e. lower than the benchmark, so that there does not appear to be any positive selection into the show according to attractiveness. beauty is negatively cor- related with age and women are, on average, rated as being more attractive than men. average ratings are more variable across women than men, con- sistent with other studies (hamermesh and biddle, ). we also coded objective participant characteristics that are related to their appearance, such as eye-color, hair-length, wearing of glasses, etc. these characteristics are correlated with our beauty measure – for women, beauty is positively correlated with hair-length, while for men, beauty is negatively correlated with having a beard or moustache and wearing glasses. this suggests that our measure of beauty captures aspects of physical attractiveness. raters may have different perceptions on the average beauty. to correct for such differences, some other studies use standardized measures. each rating is adjusted for the mean rating of that rater, and is then normalized by dividing by the standard error (see e.g. mobius and rosenblat, ). we chose to have many different raters rating different subjects. the means are not comparable among raters, because the sample of episodes they rated were partly different. we therefore prefer to use the raw data. however, if we standardize ratings for the subsamples of ratings made for the same players, the results remain very similar. table - summary statistics attractiveness mean (st. dev.) min max all (n = ) . (. ) . . men (n = ) . (. ) . . women (n = ) . (. ) . . age ≥ (n = ) . (. ) . . age < (n = ) . (. ) . . note: attractiveness of players is averaged across raters. beauty and behavior given the many potential determinants of performance and monetary pay- offs on the show, we study each of these in turn. . beauty and performance we first investigate the relationship between beauty and performance in an- swering quiz questions. the total earnings of a player in a round is probably the most important measure of overall performance. the player with the highest earnings becomes the lead player for that round, making the elimi- nation decision. in the first two rounds the lead player’s earnings determine the initial capital for all remaining players in the next round. in the third round, a player’s earnings are added to the total stake, if he is either the lead player or not eliminated by the lead player. our focus is mainly on the first round, since this is the round with the least prior selection. since players compete to answer each question, their performance in the game is a relative measure. if there is a relation between beauty and performance then this will depend on the composition of players within an episode. hence, we cannot draw conclusions from simple cross-correlations over episodes. instead, we look at the relationship between attractiveness and relative ranking in the game. two player positions, the first and the last, are of particular interest. the player who is ranked first in terms of earnings must choose one of the others for elimination, and cannot be eliminated himself in that round. the last ranked player is an obvious candidate for elimination. we estimate a conditional logit model for the probability of being in the first or last position conditional on participating in the same episode. the conditional logit is a natural framework for modelling choices from a set of alternatives. in our context, the alternatives are the players in the round, and each player i in show j has a vector of attributes xij (gender, age, attractiveness). the conditional logit model has the form: p(yij = ) = exp(β xij)p i exp(β xij) for i = , ... , where yij is an indicator variable which takes value one when the player is in the first (respectively last) position. the results are reported in table , columns and . in addition to at- tractiveness, we also control for age and gender, and for a number of dummy variables describing the register of the introductory speech: whether the player mentions his marital status, whether he has children or not, talks about his profession or studies, or about his hobbies. attractiveness is un- correlated with the probability of ending first or last. only one covariate turns out to be significant; players who mention their marital status are less likely to be ranked first. to investigate further the correlation between the players’ attributes and their rank in terms of earnings, we estimate a rank-ordered logit model (a refinement of the conditional logit) that ex- plicitly takes account of the ranking of players within a game and specifies this ranking as a function of their relative attributes. the results are re- ported in the third column of table . we find no clear correlation between any of these characteristics and earnings ranking. in particular, there is no evidence that attractive people rank differently from unattractive ones. one important assumption for the validity of the conditional logit estimates is inde- pendence of irrelevant alternatives. our tests show that this assumption is not rejected. table - attractiveness and performance, st round ( ) ( ) ( ) prob. ranked first prob. ranked last score ranking end of st round attractiveness . (. ) . (. ) -. (. ) age . (. ) . (. ) -. (. ) female -. (. ) . (. ) -. (. ) register of introductory speech - is married / has a partner - . (. )*** -. (. ) -. (. ) - children . (. ) . (. ) . (. ) - study / profession . (. ) . (. ) -. (. ) - hobby - . ( . ) -. (. ) . (. ) n. obs. pseudo r-squared . . - method cond. logit cond. logit rank- ordered. logit notes: *** % significance level, in col ( ), is lowest score and highest. . . decomposing performance performance in this game depends on a number factors: the choice of ini- tial capital and investment, the decision to press the buzzer or not, and, finally, the answer itself. these decisions depend upon the player’s ability, confidence, and risk aversion. mobius and rosenblat ( ) argue that con- fidence explains a substantial part of the beauty premium. they find that "employers" have higher estimates of the productivity of more attractive in- dividuals, even though they are given independent evidence on productivity. an intriguing finding is that attractive subjects are estimated to have higher productivity even when their interaction with the employer is only oral, not visual. mobius and rosenblat attribute this to the higher self-confidence of attractive workers, and this explains about % of the beauty premium. in the context of this game, we would expect highly confident players to be more active in the game in terms of investment and answering questions. recall that by being the first to press the buzzer, player i faces a lottery where he gets yi (his chosen investment level) if he is correct, and gets −yi if incorrect. let pi be the subjective probability assigned by i to his answer being correct. let xi be his current score, and let vi(.) denote his expected continuation value in the game after this question. it is optimal for player i to answer to the question if his expected continuation value from answering is weakly greater than his value at the current score. this implies that player i will answer the question if pi exceeds a critical threshold: pi ≥ vi(xi)−vi(xi −yi) vi(xi + yi)−vi(xi −yi) ≡ p̄i, where p̄i ∈ ( , ) as long as vi is strictly increasing in the player’s earn- ings. notice that the threshold value, p̄i, is larger if the player is more risk averse, i.e. if vi(.) is more concave. since we observe the frequency of correct answers for every player, we have an estimate of qi, the objective probability that a player is correct conditional on answering. that is, we have an estimate of e(qi|pi ≥ p̄i). a player who is more risk averse will have a higher threshold value p̄i, and will therefore answer fewer questions but be observed to answer a greater proportion of questions correctly. a player who is more confident – i.e. has a greater value of pi for a given qi – will answer more questions and will make more mistakes. in other words, risk aversion and lower confidence act in very much the same way, in reducing both the number of answers and also the proportion of incorrect answers. on the other hand, if a player is less knowledgeable, and objectively has a lower value of qi, this will ceteris paribus reduce the number of answers but not raise the proportion of correct answers. we concentrate our analysis on the decisions made in the first round, since the second and third rounds could be subject to selection biases due as the player thinks about the question, his subjective probability will evolve over time. the analysis that follows pertains to any instant of time, so the continuation value from not pressing the button (vi(xi)) includes the option value of waiting, and possibly pressing the buzzer in the future, if no one else presses in interim. to the elimination decision. table presents the results of ols estimates of the determinants of initial capital, share invested, number of answers and percentage of good answers (columns to respectively). we do not find that attractive players are more confident. if they were, they should invest more, be more likely to answer, and, conditional on answering, perform worse. we do find a systematic difference according to gender: women are much less likely to answer a question. this is what you would expect if women are more risk averse or less confident. however, conditional on answering, they actually do not perform better than men, what you would expect with risk aversion or lack of confidence. in the second round, we even find that they are significantly less likely to answer correctly. we also did not find any evidence that the topics of the questions could explain gender differences in performance. overall, these results suggest that the reason why women are less likely to answer is not due to a wrong perception of their ability or a higher degree of risk aversion, but rather because they are less able to answer the type of questions on the show. our measure of confidence is based on actual behavior. it could be the case that attractive players areperceived more confident by other players. to investigate this, we constructed a measure of perceived confidence, by hav- ing independent raters assess the confidence of a player on a point scale. each player was rated by to raters, and each rater saw players. our player specific measure of confidence is the mean across raters. column ( ) of table shows the results of an ols regression of perceived confidence on the characteristics of the players. we find that perceived confidence is sig- nificantly positively correlated with attractiveness. thus, attractive players appear more confident but do not behave more confidently. the reason for we have analyzed separately the decisions made for the bonus question. again, we found that attractiveness is uncorrelated with the share invested or the probability of giving a correct answer. the results are not reported for the sake of brevity. alternative econometric specifications (conditional logit estimates for the probability of answering and logit estimates for the probability of answering correctly) give similar results to the ones presented here. table - attractiveness, performance and confidence, st round ( ) ( ) ( ) ( ) ( ) initial capital share invested n. of answers share correct answers perceived confidence attractiveness . ( . ) -. (. ) . (. ) -. (. ) . (. )*** age . (. )*** -. (. )** . (. ) -. (. ) . (. ) female -. ( . ) . (. ) -. (. )*** . (. ) -. (. )*** register introductory speech - is married/partner . ( . ) . (. ) -. (. )** -. (. ) . (. ) - has children -. ( . ) -. (. ) . (. ) . (. ) . (. ) - study / profession . ( . ) . (. )* -. (. ) . (. ) . (. )** - hobby - . ( . ) -. (. ) . (. ) -. (. ) -. (. ) constant . ( . )*** . (. )*** . (. )** . (. ) . (. )*** n. obs. notes: ols estimates, * significant at % level, ** % level and *** % level, col ( ) include players who gave at least answer. standard errors are clustered by episode in col ( ) to ( ). col. ( ) includes predictor fixed effects and standard errors are clustered at the player level. our finding may be that players receive continuous feedback on their per- formance. this contrasts with the set-up of mobius and rosenblat, where subjects did not receive systematic feedback on their performance through the experiment. we should also mention that in their study, there is no inter- action between subjects who are assigned the role of "employers" and those assigned the role of "workers", so that consumption value considerations may be naturally less important. . beauty and cooperativeness players can only materialize their gains in this game in the final stage, where the two remaining players play a prisoner’s dilemma game and de- cide simultaneously to share the accumulated money or not. a companion paper (belot et al., ) conducts a comprehensive analysis of the deter- minants of sharing behavior. the key findings are that own characteristics matter – specifically, women are more likely to share than men. however, the characteristics of the opponent turn out to be irrelevant to the sharing decision. we augment this analysis by including the player’s own beauty rating and the opponent’s beauty rating as explanatory variables. the results are reported in table . we find no correlation between beauty and cooperative behavior. attractive players are no more (or less) likely to share – indeed, the coefficient is very close to . attractive opponents are also no more (or less) likely to induce sharing behavior from their opponents. this is interesting – although our overall results suggest that players obtain con- sumption value from having attractive co-players, they are no more likely to share with them. it is possible that attractive people are perceived as being more coopera- tive even though they are not really so, so that selection decisions are driven by incorrect beliefs. while we do not observe the beliefs of participants on the show, a companion paper (belot et al. ( )) experimentally inves- tigates third party perceptions of trustworthiness. experimental subjects watched a random sample of shows and were asked to report a probability that a player would share. column of table reports our findings on the relation between beauty and perceived cooperativeness. our subjects predict that attractive people tend to be slightly less cooperative, although the effect is small. it therefore appears that attractive people are not only not more cooperative, they are also not perceived to be more cooperative by third parties. the coefficients are potentially biased if lead players use private signals to select players, since the sample of unattractive players may be unusually cooperative. belot et al. ( ) addresses this issue and find no evidence of bias. other experimental evidence on the relation between attractiveness and cooperation is mixed – see mulford et al. ( ), solnick and schweitzer ( ), eckel and wilson ( ) and andreoni and petrie ( ). table - attractiveness, sharing & perceptions of sharing ( ) ( ) ( ) pr. sharing pr. sharing perceived prob. sharing own attractiveness -. (. ) -. (. ) -. (. )** opponent’s attractiveness -. (. ) age . (. ) . (. ) . (. ) female . (. )** . (. )** . (. )*** contribution to prize money (%) -. (. )** -. (. )** -. (. )** total prize (x € , ) . (. )** . (. )*** . (. )*** constant . (. )*** n. obs. method bivariate bivariate ols probit probit notes: * significant at % level, ** % level and *** % level; ( ) and ( ) are bivariate probit estimates, standard errors clustered by episode; the marginal effects in ( ) and ( ) are computed at the means of the lead player’s characteristics. ( ) includes subject fixed effects. beauty and selection we now study the elimination / selection decision, having established that there is no objective reason to discriminate in favor of attractive players either on the grounds of performance or because they are (thought to be) more cooperative. thus any bias towards attractive players in lead player selection decisions can plausibly be attributed to the lead players obtaining consumption value from having attractive co-players. an important advantage of the rules of our game show is that in mak- ing the elimination decision, the lead player in any round is faced with a relatively simple decision problem, rather than a game. if the lead player chooses to eliminate player i then the lead player is decisive and i will play no further part in the game. in contrast, elimination decisions in other game shows (such as the weakest link, analyzed by levitt ( ) and antonovics et al. ( )) are often made by majority voting, involving all the partici- pants remaining at that stage. if a player j votes to eliminate i, then i may not be eliminated, and may in turn vote against j at a later stage. this implies that players have a strong incentive to vote to eliminate whoever they think others are going to vote against. in other words, there are mul- tiple voting equilibria, and this is coupled with a strategic dynamic motive to vote with the majority. this may induce a significant role for irrelevant characteristics as possible focal points, even when players do not have any preference for discriminating on the basis of such a characteristic. in the context of our game, these strategic considerations do not apply, since only the lead player votes and his vote is decisive. thus evidence of discrimination can be attributed to lead player preferences. figure shows the average attractiveness of all players in each round, and that of the players who are eliminated in that round. in each round, eliminated players are less attractive than average, and in consequence, av- erage attractiveness increases steadily over the rounds. other summary statistics confirm this picture. if a player is average-looking (i.e. within one standard deviation of the mean), he or she has . probability of reaching the final round. an attractive player has a substantially higher probability of . , while an unattractive player’s probability is only . (see table ). table - attractiveness and survival, by round % reaching % reaching % reaching round round final attractive average-looking unattractive note: attractive (unattractive) is more than one standard deviation above (below) the mean. we investigate in more detail the role of physical attractiveness in the selection decision by the lead player by estimating a conditional logit model, where the dependent variable indicates whether the player was eliminated . . . . . . . round (n = ) round (n = ) round (n = ) final (n = ) ave ra ge bea uty players all players eliminated player figure : average beauty of all players and eliminated players. ( ) or not ( ). we start by focusing on the first round, where the sample is largest and no selection has taken place. later on we discuss results for other rounds. the results are shown in table . the first regression includes no other covariates, the second controls forperformanceand individual characteristics and the third controls for measures of confidence. the results are reported in terms of odds ratios with a reference value of . these have an easy interpretation. an odds ratio above (below) signifies that the attribution increases (decreases) the probability of being eliminated. we find that unattractive players are significantly more likely to be elim- inated than average-looking players. when we control for performance and measures of confidence, we predict that unattractive players should be three times as likely to be eliminated as average-looking players. in contrast we do not find that more attractive players are better treated. hence, our re- sults point in the direction of an ugliness penalty, in line with the results of hamermesh and biddle ( ). table - probability of being eliminated, st round conditional logit estimates (odds ratios) ( ) ( ) ( ) attractiveness unattractive . ( . )* . ( . )** . ( . )** attractive . (. ) . (. ) . (. ) performance fourth highest . (. )** . (. )*** third highest . (. )*** . (. )*** second highest . (. )*** . (. )*** confidence % capital invested . (. ) n. answers . (. ) perceived confid. . (. ) female . (. ) . (. ) age . (. ) . (. ) controls for topic registry introduction no yes yes n. obs. pseudo r-squared . . . notes: significance levels: *: percent, **: percent, ***: percent. note that age and gender are irrelevant in the selection decision. also, the score ranking is a very good predictor of elimination: the player with the lowest score (the reference category) is more than twice as likely to be eliminated as the one ranked fourth, and more than five times as likely to be eliminated as the one with the second highest score. finally, controls for behavior during the game do not change the results and do not matter as such in the selection decision (column ( )). less attractive players are dis- criminated against, for reasons that are uncorrelated with their performance or behavior during the game. . discrimination over the rounds one explanation for the discrimination taking place in the first round is that players have very little information about each other. they had relatively little time to get to know each other and to learn about each other’s ability. with so little information, perhaps they retreat to attractiveness to select one player over another. if this is the reason, we expect discrimination to disappear over the rounds when more information becomes available. however, since discrimi- nation takes place in the first round, the population of players becomes more attractive on average and less heterogeneous, which should reduce discrimi- natory practices. the fact that there are fewer unattractive people around also makes it harder to identify an effect. so we also propose a specification based on a relative measure of beauty, where we identify the least attractive player among the remaining contestants with a dummy variable. the first two columns of table show estimation results comparable to column ( ) of table , for the second and third round respectively. columns ( ) to ( ) show the results for the specification including the dummy for the least attractive player for each round, including the first one. we find no evidence of discrimination based on attractiveness in the second round. gender is the best predictor of the elimination decision in the second round, with women being substantially more likely to stay in the game. we will come back on that point in the next section. in the third round, we find evidence of discrimination against the least attractive player, and the coefficient is comparable to the first round. so discrimination does not disappear with learning about player ability. table - probability of being eliminated in nd and rd round conditional logit estimates (odds ratios) ( ) ( ) ( ) ( ) ( ) round unattractive . (. ) . (. ) attractive . (. ) . (. ) least attractive . (. )** . (. ) . (. )** n. obs. all regressions control for the same variables as table , col. ( ), ** indicates significance level at percent . gender differences in discriminatory behavior we nowexplore the natureofdiscrimination in greater detail. we investigate the relation between discrimination and gender. do men care more about looks than women do? do people care more about the looks of the opposite sex? table reports separate regressions for male and female lead players. we find that women do discriminate more against the least attractive player than men do, i.e. women seem to care more about looks than men do. the difference in coefficients between male and female lead players is not significant though. columns ( ) and ( ) investigate the elimination decision when the lead and least attractive player are of opposite sex on the one hand, and of the same sex on the other hand. we find that discrimination is indeed greater when the candidates for elimination are of the opposite sex. the difference in coefficients is significant at the % level. this could explain why women discriminate more, since the least attractive player in the first round is more likely to be a man (men being on average less attractive than women). we have found almost identical results for the last selection round, where the discrimination against the least attractive player took place in games where the lead player and the least attractive player were of opposite sex (results not reported for the sake of brevity). since in the last round, most lead players are men, the discrimination plays mostly against women. overall, these results reinforce the idea that beauty has a consumption value, and that this is the main reason why people discriminate against less attractive players. table : discrimination and gender of the lead player ( st round) conditional logit estimates (odds ratios) lead player female lead player male lead player and least attractive - opposite sex lead player and least attractive - same sex ( ) ( ) ( ) ( ) fourth highest score . (. )* . (. )* . (. )** . (. ) third highest score . (. )* . (. )** . (. ) . (. )*** second highest score . (. )** . (. )*** . (. )** . (. )*** least attractive . ( . )** . (. ) . ( . )** . (. ) age . (. ) . (. ) . (. ) . (. ) gender . (. ) . (. ) . (. ) . (. ) n. obs test equality coefficients for the least attractive ( ) = ( ) p-value ( ) = ( ) p value . . notes: equality of coefficients is tested with a generalized hausman test significance levels: *: percent, **: percent, ***: percent. . costs of discrimination and the benefits of beauty we now provide an estimate of the benefits of beauty and the costs of dis- crimination. as in many other game shows, the rules are such that most contestants go home empty handed. in fact, only out of contestants (i.e. %) take any money home. moreover, even among those with pos- itive earnings, the variance is very large (the standard deviation is € , compared to the mean of € , ). these factors imply that there is a high degree of noisiness in earnings, making it a priori difficult to get statistically significant results. furthermore, given the large number of zeroes, our esti- mates are not directly comparable to estimates of the beauty premium from the labour market such as those of hamermesh and biddle ( ). column in table presents ols estimates of the determinants of log earnings. an increase in attractiveness of one standard deviation increases earnings by percentage points. despite the large standard error, this is significantly different from zero at the % level. an alternative estimate of the beauty premium is based on estimating the probability of reaching the final round. columns and provide estimates of the probability of reaching the final round with attractiveness as a continuous variable (column ) or as a discrete variable, based on the ranking of players within each show according to attractiveness (column ). the results confirm our previous findings: the two most attractive players are about twice as likely to reach the final round than the least attractive player ( % against % with a standard error of percentage points). this means that, on average, their expected earnings are twice as large. note that if we take a very conservative approach and consider the lower bound of the % confidence interval for the probability of reaching the final round, we still have a difference of percentage points in terms of probability of reaching the final round between the most and least attractive players. in this case, the estimated lower bound on the beauty premium equals %, which remains substantial. table : the beauty premium log earnings probability of reaching final round ( ) ( ) ( ) gender -. (. ) . (. ) . (. ) age -. (. ) . (. ) . (. ) attractiveness . (. )* . (. )* beauty rank (least attractive) - - beauty rank . (. ) beauty rank . (. ) beauty rank . (. )** beauty rank (most attractive) . (. )** constant . ( . ) n. obs. pseudo r-squared . . . notes: col. ( ): ols estimates allowing for a show-specific random effect; cols ( ) and ( ): conditional logit estimates (odds ratios); **: percent, *: percent. turning to the costs of discrimination, stakes are substantial on the game show. by eliminating the least attractive players instead of players who would maximize their monetary payoff, players implicitly pay a price for keeping more attractive players in the game. while we cannot directly calculate the price for keeping more attractive players in the game in the first or second round (since we do not observe the earnings of those who are eliminated), we can do a back-of-the-envelope calculation of the price they pay by eliminating the least attractive player in the third round, where we do observe perfectly the earnings of the contestants. however, the sample of observations is relatively small and the results should be taken with caution. we can identify of the episodes where the lead player eliminates the least attractive player, even though he does not have the lowest score. in these episodes, the less attractive players have earned € more on average than the player who is chosen to play the final. hence, by eliminating the least attractive players in these cases, the lead player diminishes the prize money e by € on average. notice that discrimination is directly financially costly in the final round – there are only two instances where the two low ranked players had the same score. this estimate is a lower bound since we are only looking at costs associated with discrimination in the third round, and not earlier rounds, since a precise imputation of financial costs in earlier rounds is more difficult. . gender differences it is worthwhile contrasting our results on beauty with differences between players based on gender. overall, women earn less than men, earning € on average, as compared to € . as with attractiveness, we can decompose the gender gap in earnings into different components. in terms of perfor- mance, we found that women were less likely to answer a question, and conditional on answering were no more likely to answer correctly (in round it might be that lead players expect those with a lower score to be more cooperative, for which there is evidence (in our companion paper). but this doesn’t explain why the player with a lower score is rarely chosen to play the final if he is is the least attractive player. , they are actually less likely to answer correctly). the lower performance of women could be due to the competitive character of the game show – gneezy et al. ( ) present experimental evidence showing that women perform worse in competitive environments, especially when they compete against men. despite the fact that women perform worse, they are as likely to reach the final round as men – % of the participants on the show are women, while % of the players in the final round of the game are female. one explanation for discrimination in favour of women in the selection decision is their greater cooperativeness, since women are more likely to share in the final round – % of women share against only % of men. however, this does not seem to be the explanation since women are no more likely to be selected than men in the last round (holding earnings constant), when the lead player selects the player with whom he will play the final round and where one may expect cooperativeness considerations to be dominant. it is more plausible that women are chosen despite their lower performance due to gender balance considerations (since women are relatively scarce in the show) or positive discrimination (since the selection decision is public). women’s’ greater cooperativeness widens the gender gap in earnings. in- deed, since women are much more likely to share in the final round, and since the opponent does not share more often when facing a woman, the differ- ence in take-home earnings across gender is larger than between individual scores. overall, we find no evidence of negative discrimination against women. the gender earnings gap is mainly driven by differences in performance and cooperativeness. perhaps the fact that the selection decision is public prevents gender discrimination – since gender is an objective and obvious our companion paper provides a comprehensive analysis of the determinants of the sharing decision in the final stage, and its implications for how selection decisions are made just before this. some participants explicitly mentioned "gender balance" as a consideration while making the selection decision in the second round. characteristic in contrast to attractiveness, which is more subtle. . insidious discrimination? are third parties aware of the possibility of discriminatory behavior? and if they are aware, is this knowledge conscious or sub-conscious? these ques- tions are relevant – if discrimination is not perceived by third parties, it may persist even under public scrutiny. to investigate these questions, we adopt a novel experimental procedure, by asking subjects to predict the elimination decision at the end of the first round of quiz questions. we focus on the first round since we do not want subject predictions to be influenced by learning from observing selection decisions in previous rounds. our sub- jects ( students from the university of amsterdam) were shown a trailer and given a handout, setting out the overall structure of the game show, and then shown a random sample of seven episodes. they were informed in advance of the identity of the lead player in the first round, so that they could focus on predicting the lead player’s decision. the subject was asked to assign a probability to the event that each of the other players would be chosen for elimination by the lead player. subjects were rewarded by using a quadratic scoring rule, giving them strict incentives to report their true beliefs. subjects were not informed of the actual elimination decision in any episode, so as to prevent any learning. at the end, we asked subjects a qualitative question: what, in their opinion, are the most important factors determining the elimination decision? subjects were permitted to list up to four such factors. table reports ordinary least squares estimates, where the dependent variable is the prediction of subject i regarding the elimination probability this is related but not identical to the notion of implicit discrimination (see greeen- wald et al. ( ) and bertrand and mullainathan ( )), which uses psychological tests to measure implicit bias, say against african-americans. it is worth noting that researchers have found an implicit bias against older people and the overweight. the subjects also filled out a questionnaire on their background characteristics. they earned on average € (for minutes), including a € show up fee. the full set of instructions is in the appendix. of player j. we have subjects, making predictions for four players in each of seven episodes, giving us observations. table - predictions of elimination in st round ols estimates ( ) ( ) ( ) ( ) ( ) ( ) attractiveness - . - . - . ( . )** (. )*** (. )*** dummy least attractive . . . ( . ) ( . )* ( . )* perceived confidence . . (. ) (. ) age -. -. -. -. . . (. ) (. ) (. ) (. ) (. ) (. ) gender - . - . - . - . - . - . ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** score rank th - . - . - . - . ( . )*** ( . )*** ( . )*** ( . )*** score rank d - . - . - . - . ( . )*** ( . )*** ( . )*** ( . )*** score rank d . . . . ( . )*** ( . )*** ( . )*** ( . )*** constant . . . . . . ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** ( . )*** n. obs. notes: standard errors are clustered by player. significance levels: *: percent, **: percent, ***: percent. our main finding is that our subjects do perceive that less attractive players are more likely to be eliminated. that is, our subjects are at least implicitly aware that discrimination on the grounds of attractiveness is likely to occur. they predict that an increase in one standard deviation in attractiveness should decrease the probability of being chosen by . per- centage points. this is substantially less than what we have estimated in subjects do not perceive any relation between a player’s confidence (as assessed by the subject) and the probability of elimination. women are predicted to be more likely to be eliminated, as are second ranked players — neither of these effects are present in the actual selection decision. the last finding appears to be due to subjects incorrectly thinking that the first ranked player may have an incentive to eliminate rivals for leadership. the actual data (the corresponding number is percentage points). inter- estingly, attractiveness is not mentioned by anyone among the two most important criteria influencing the selection decision, and only subjects list attractiveness at all. this provides suggestive evidence that discrimination is insidious, since subjects appear to be implicitly aware of its existence, but not consciously so. this is particularly noteworthy since a subject is detailing the motivations of players on the game show (rather than him- self), and would therefore have little psychological reason to lie or practice self-deception. discrimination on the basis of looks appears to meet with less social dis- approval than other forms of discrimination. following a report in new sci- entist summarizing the findings of the present paper, it was covered by news- papers in several countries including the uk and the netherlands. press coverage in the dutch newspaper “de telegraaf” triggered a large public response – within a day, readers had posted a response on the newspa- per’s website. we coded these responsesand found that of these suggested that beautiful people "deserve" to be treated better than the "ugly" – some comments were quite offensive about unattractive people. people simply acknowledged the results and gave further examples ofdiscriminatory behav- ior against ugly people. only six people explicitly condemned this kind of discriminatory behavior. furthermore, many people simply found the find- ings somewhat amusing (as did some of the articles in the popular press), rather than a matter for social concern. while its readers are unlikely to be representative, the newspaper is the largest with over , circulated copies daily. it is noteworthy that we find this response in the netherlands, a country that is well known for its progressive and liberal attitudes towards some minority groups (e.g. gay people), and one with a strong commitment to equal opportunities. our experimental findings (and the public response) raise important is- fershtman and gneezy ( ) find that experimental subjects who discriminate seem to be unaware that they do so. sues of social concern regarding the persistence of discrimination. following becker ( ), economists have focused on the extent to which the forces of competition and profit maximization eliminate discrimination. it is arguable that the social stigma associated with racial or gender discrimination is no less important a force in its elimination. to the extent that discrimination on the basis of looks or age occurs, but is either insidious or is "acceptable" even when perceived, its persistence is enhanced. . external validity one possible concern with our study is external validity, especially if the participants on the show are not representative of the population. while genuine field data on attractiveness and individual productivity might be ideal, this is hard to get, and laboratory experiments or our type of study seem to offer the best hope for disentangling the beauty premium. the producer of the show told us that no explicit criteria were used in recruit- ing participants – in particular, applicants were not required to submit a photograph, so that the producers do not seem to have been concerned with having good looking people. nor does it seem, from viewing the show, that attractive people self-select into the show. this impression is confirmed by the fact that the average rating of our participants in terms of attractive- ness is . , whereas raters were told to use as the benchmark for average attractiveness. participants also come from a variety of occupations, an advantage that compares favorably with laboratory experiments. given the lack of emphasis by the producers on attractiveness, it appears unlikely that participants’ behavior on the show reflects an internalization of such concerns. in view of our findings, it is also relevant that dutch society seems less concerned with beauty than other similar societies. spending on cosmetics and toiletries as a proportion of gdp is lower in the netherlands than most harrison and list ( ) have an extensive discussion on the external validity of game show data. other west european countries – the netherlands is (joint) fourth from the bottom in the list of the eu fifteen. the fact that we find discrimination in such a context seems particularly compelling. concluding comments to summarize, our main finding is that beauty is "only skin-deep", and has no implications for a person’s performance or their cooperativeness. nev- ertheless, it is an attribute well worth having. attractive players earn a premium, that arises from the reluctance of other players to eliminate them. this seems to reflect consumption value considerations on the part of the other players in the game. the preference for the beautiful is therefore a form of taste based discrimination. our finding is also noteworthy since participants on a tv show would be reluctant to discriminate, since their behavior is subject to public scrutiny. while discrimination on the basis of gender or race are rightly frowned upon, discrimination based on a per- son’s physical appearance is less remarked upon. indeed, it is likely that discriminators, the discriminated against and third parties are less aware of the phenomenon, so that it is, to some extent, insidious. our experimental evidence on third-party perceptions of discrimination is suggestive in this regard. we believe that discrimination on the basis of less obvious criteria such as attractiveness is likely to have qualitatively different characteristics from discrimination based on recognized categories. without overstating the external validity of our results, we believe that this raises important questions for society and social policy, and merits further research. the role of beauty is less suprising in argentina, where mobius and rosenblat’s ( ) experiment was conducted. buenos aires is known as the "plastic surgery capital of the world". references [ ] altonji, j.g., and r.m. blank ( ), race and gender in the la- bor market, in o. ashenfelter and d. card (eds.), handbook of labor economics, amsterdam: north holland. 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[ ] solnick, s. and m. schweitzer ( ), the influence of physical at- tractiveness and gender on ultimatum game decisions, oganizational behavior and human decision process ( ), - . appendix: instructions [translation from dutch.] welcome! the experiment lasts for about minutes. during the experiment you will earn points that are worth money. the exact amount you earn depends on your score and can earn up to about € . none of the other participants will know what you earn and all your answers will be confidential. how you earn money you will see fragments of a television game show. you will be asked to predict the choices of contestants. the more accurate your predictions are, the higher your score and the more money you earn. only your own predictions determine your score and not the predictions made by other participants. the tv show the game show starts with candidates. in the first round, the candidates have to answer quiz questions. their score depends on the number of questions they answer correctly. at the end of the round, one candidate is eliminated by the highest-scoring candidate. you will only see the first round, and your main task is to predict who will be eliminated. you will see episodes, based on a random selection from all episodes. for background information, we also explain the rest of the game show. you will not see any of this part of the show and do not have to make any predictions about it. there at two more rounds after the first round, where again the highest scoring person has to eliminate one of the others. after these rounds, there are two candidates left. the scores of both candidates are added. this is the amount of money they will be playing for. both players simultaneously decide whether to share or grab. there are three possible situations. ( ) they both share. in this case, they both get half of the amount of money. ( ) one candidate shares and the other does not share. in this case, the one who does not share gets the whole amount. the candidate who shares gets nothing. ( ) they both do not share. in this case, nobody wins any money. before they make their share/grab decisions, candidates have the opportunity to say something to each other. instructions we start by showing the candidates introducing them- selves. you will see every candidate twice. the first time, there will be no sound and we ask you to predict the age of the candidates. the second time, you will see the candidates introducing themselves again, but with the sound. we ask you to rate the self-confidence of the candidate. you can do this on a scale from (very low self-confidence) to (very high self-confidence), taking as the average of all dutch people. after the in- troduction of the candidates, you will see the first round of quiz questions. after the end of the first round, the person with the highest score chooses which other candidate will be eliminated. at that point, we pause the show, and we will ask you to predict how likely it is that a certain candidate will be eliminated. the way we ask you to do this is as follows. the candidate with the highest score can choose one out of the four candidates. we ask you to divide pointsbetweenthese four candidates, inproportion to the likelihoodthat they will be eliminated. you can divide the points in any way you like, as long as the total equals . you should give more points to a candidate the more likely you think that this candidate will be eliminated. if you give points to one candidate, this means you are certain that this candidate will be eliminated. if you give zero points to a candidate, you are certain that this candidate will not be eliminated. [several examples were given.] to summarize, you give more points to a candidate if you think that candidate is more likely to be eliminated. in total, you allocate points over the four candidates. for any candidate, you can use any whole number from to (thus including numbers such as , , etc.). notice that the total number of points should add up to . however, you will not be penalized if the numbers you choose do not add up. if you allocate less, say only points, we will reallocate the remaining ten points in the same ratio as your original allocation. if you allocate more points (say points in total), then we will scale back the points proportionally, in this case by multiplying your allocation by / . after filling in your answer sheet we ask you to put it in the envelope on your table. after you do this, you are not permitted to take it out of the envelope. hence, you can not go back to an earlier question. your earnings at the end of the experiment, we compare your pre- dictions to the actual outcomes. you score is higher if your predictions are better. the most you can earn per prediction is points and minimum is points (you will see episodes). every point is worth c= . . for every age prediction within years of the true age, you receive c= . . your con- fidence ratings have no impact on your score. the amount you earn for the selection predictions is calculated by the formula below. this formula is chosen in such a way that it is in your interest to report your true beliefs. by reporting any other number than what you truly believe, your expected earnings are decreased. a proof of this can be requested at the end of the experiment. questions? please ensure yourself that you have understood the in- structions. if you have any questions, please raise your hand and wait until somebody comes to you. formula of your score your score is calculated in such a way that it is best for you to report your best prediction. you do not need to understand how your score is calculated in order to do well in this experiment. however, for those who want to understand the details, we explain this below. suppose you allocated pi points to candidate i, i = , , , . if candidate i is indeed selected to be eliminated, the score for your prediction is: − ( −pi/ ) − x j =i (pj/ ) . your expected score is maximized by reporting what you really believe. a proof of this can be obtained at the end of the experiment. pond research and management in europe: "small is beautiful" hal id: hal- https://hal.archives-ouvertes.fr/hal- submitted on dec hal is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. the documents may come from teaching and research institutions in france or abroad, or from public or private research centers. l’archive ouverte pluridisciplinaire hal, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. pond research and management in europe: ”small is beautiful” dani boix, jeremy biggs, régis céréghino, andrew p. hull, thomas kalettka, beat oertli to cite this version: dani boix, jeremy biggs, régis céréghino, andrew p. hull, thomas kalettka, et al.. pond research and management in europe: ”small is beautiful”. hydrobiologia, springer, , vol. , pp. - . � . /s - - - �. �hal- � https://hal.archives-ouvertes.fr/hal- https://hal.archives-ouvertes.fr open archive toulouse archive ouverte (oatao) oatao is an open access repository that collects the work of toulouse researchers and makes it freely available over the web where possible. this is an author-deposited version published in : http://oatao.univ-toulouse.fr/ eprints id : to link to this article : doi: . /s - - - url : http://dx.doi.org/ . /s - - - to cite this version : boix, dani and biggs, jeremy and céréghino, régis and hull, andrew p. and kalettka, thomas and oertli, beat. pond research and management in europe: "small is beautiful". ( ) hydrobiologia, vol. (n° ). pp. - . issn - any correspondance concerning this service should be sent to the repository administrator: staff-oatao@listes-diff.inp-toulouse.fr pond research and management in europe: "small is beautiful" dani boix· jeremy biggs ·régis céréghino · andrew p. hull· thomas kalettka ·beat oertli the phrase "small is beautiful" was fust used by the talented scholar leopold kohr ( - ), but it became more popular thanks to the essays of one of his students, the british economiste. f. schumacher, and it was coined as a response to the socially established idea that "big is powerful". lt could be argued that this desire for "bigness" exp lains wh y current legal frameworks and the conservation planning and d. boix (lei) institute of aquatic ecology, university of girona, girona, catalonia, spain e-mail: dani.boix@udg.edu j. biggs pond conservation, oxford, uk r. céréghino university of toulouse, toulouse, france a. p. hull liverpool john moores university, liverpool, uk t. kalettka centre for agricultural landscape research, muncheberg, germany b. oertli university of applied sciences western switzerland, geneva, switzerland management related to standing waters often overlook ponds, despite their well-known value in terms of biodiversity and socio-economic benefits (oertli et al., ; céreghino et al., ). of course, this is only one of severa! possible explanations, but it is impor- tant to understand that such long-established ideas can have a lasting effect upon the efficiency of our conservation actions. beyond this social perspective, the history of science can also provide sorne explana- tion as to why ponds have been undervalued for so long. sorne of the fust limnological work was undertaken during the late nineteenth--early twentieth century by the swiss scientist françois-alphonse forel on the ecology of lake geneva ( , , ). from this, one of the fusts treatises of limnology- "die binnengewàsser mitteleuropas" (thieneman, )-included a chapter on standing waters that included lakes, ponds, pools and bogs, but most of the chapter focussed upon the larger bodies of water-a trend replicated in the limnology books which fol- lowed (e.g. arévalo, ; naumann, ; ruttner, ; dussart, ; wetzel, ; margalef, ). lakes, therefore, were the "cradle" of limnological studies. during the second half of the twentieth century, the study of limnology broadened to include the ecological processes in rivers and streams, thanks mainly to the h. b. n. hynes' masterful revision of the subject (hynes, ). ponds, however, remained overlooked and received significantly less scientific attention than streams, rivers and lakes. this is more surprising when several studies have established that ( ) on a global scale they cover a greater total area than lakes (downing et al., ); ( ) their typical charac- teristics, such as shallow waters and small size, imply a different ecological functioning (oertli et al., ; s! ndergaard et al., ); ( ) they play a major role in global cycles (downing, ) and ( ) they have high aquatic biodiversity (wood et al., ; williams et al., ). despite the evidence that ponds perse receive less scientific attention than other water bodies (oertli et al., ), in the scientific literature "ponds" are often included under other terms such as "shallow lakes" ( e.g. scheffer et al., ; moss et al., ) or "wetlands" ( e.g. gopal et al., ; van der valk, ), as in the usa where the term "wetlands" is often used to describe "ponds" (batzer & wissinger, and references therein; batzer et al., ). these more general definitions may significantly reduce the level of scientific interest and could go sorne way to explain sorne of the biases that are regularly observed today in europe's water framework directive (wfd) (miracle et al., ). ponds are too small to fit the standard model of site-based protection and they do not fit the standard model of consent-based protection applicable to lakes and running waters under europe' s most powerful piece of water legislation. in this context, three emerging ideas have to be taken into account in pond management decisions: ( ) the importance of pond networks in addition to isolated ponds (gibbs, ; jeffries, ); ( ) to consider lesser known floral and faunal groups which, nevertheless, contain high biodi- versity (i.e. diatoms, meiofauna and insects), and to use surrogate species with caution (i.e. having sorne idea of their effectiveness for the circumstances in which they will be applied; favreau et al., ; gascon et al., ; bagella et al., ); and ( ) differences in the community structure and ecological functioning of water bodies throughout europe imply, for example, that sorne limnological paradigms used in the manage- ment of cold temperate ponds cannot be generalised to the mediterranean region (Âlvarez-cobelas et al., ; brucet et al., , ). ponds, neglected but fascinating habitats traditionally relatively few stakeholders were impli- cated in the management of ponds. nowadays, the growing importance of a global society means that information is easy to obtain and not restricted to just a few stakeholders. however, describing the relation- ship between society and ponds is not easy; it requires the work of a multidisciplinary team including not only natural scientists but also social scientists, cultural historians and stakeholders directly involved in the planning process. although this is an interesting and highly relevant debate, it will not be our principal focus in the present preface. specifically, we will address first the human attraction and appeal of ponds, and, second, whether or not our genuine fascination and concem over the loss of these vital wetland habitats is adequately projected to an increasingly aware general public. finally, we will review the various initiatives which have been taken over the past decade to address this issue. water bodies have attracted the attention of human beings for a long time. in aristotle's "the history of animais", he noted several curious observations about ponds and defended the seemingly spontaneous gen- eration of life from mud or sand (referring to "fish", perhaps he had observed fairy shrimps because he was talking about temporary ponds) and rain (talking about eels). examples of this attraction for ponds can be found in the non-scientific literature, art and popular culture which describe their magnetism. in the first pages of joseph kessel' s book "le lion", the narra tor feels a spontaneous and irrational desire to go to the pond where many different species of mammals enjoy a peaceful co-existence (kessel, ). even today, game lodges in east africa provide tourists with spectacular views of the "water hole" to allow people to see the parade-like sequence of animais (elephants, baboons, waterbucks, warthogs, etc.). similarly, this powerful attraction is well represented in a popular painting, "waterhole dreaming" by lynda brown nabanunga from the djaru wa tribe (western aus- tralia). it depicts the desert in a period of drought and in order to survive ali of the wildlife and the aboriginal people of the area have come to the main water hole for water. for the american author gene logsdon his book "the pond lovers" relates the life histories of people who describe the intense feeling towards water with the words "the attraction to water is in our genes" (logsdon, ). legends, myths and tales from different human cultures talk about ponds or pond life (e.g. herons and pond fish appear in the tales of the south american wichi people; hippos and crocodiles in the tales of the mrican ndebele people; and beavers and frogs in the tales of north american sinkiuse salish people). in sorne areas of europe ponds are veiled in mystery and fairy creatures were believed to live in them (as the scottish "urisk" and "glaistig", the former ugly and peaceful and the latter beautiful and dangerous; or the catalan "dones d'aigua", female spirits with dragonfly or butterfly wings who live in ponds or streams and sometimes take care of the children and other times kidnap them). however, they are also the scenario oftraditional tales ("the talking pond fish", a tale explained in severa! parts of europe with sorne regional differences) and of modem tales ("the tale of mr. jeremy fisher" by beatrix patter, a story of a fishing frog). ponds have always been the preserve of people. their size has made them sui table for many human uses and over the past two millennia they have become part of the daily lives of people around the world. however, if ponds provide such fascination and utility for human beings then why do we neglect them more than other habitats? maybe, both aspects provide the answer: the human attraction to ponds can stimulate the capture of organisms, and the size of ponds allows people to transform and modify them very easily. if ponds have little or no economie function then it is very easy to fill them in. in the united kingdom after the second world war, the intensification of agriculture meant that small wetlands were drained or filled in. modem machinery meant that a pond which had served as a watering hole for livestock for many centuries could be filled in less than a day-from wetland to dry land in a matter of hours. of course, capturing plants and animais and transforming our landscape is part of human nature, but, we would argue, so is the attraction of wildlife itself. apart from its recently acknowledged economie value, by the start of the twenty-first century the benefits of nature conservation had assumed a new role---providing succour for a healthy society. involvement in nature conservation-whether actively or passively, is now seen as a remedy for healthy living and living in a pleasant environment enhances our quality of life. in this sense, ponds provide a manageable human scale habitat in which the impact of local action can be seen in a short space of time. in parts of europe where nature conservation is well-established, such as the united kingdom, conservation plans are more easily carried out thanks to greater social sensibility (drake & pickering, ; hull, ). in such countries, the availability of ad vice and guidance about the natural values of ponds for people of ali ages is widely accessible (e.g. engelhardt, ; ammann, ; jennings, ; deom, ; taylor, ; wood & dean, ; biggs et al., ; kolvoort & gates, ) and, increasingly, online. furthermore, this work is sup- ported by a vast library of nature guides covering the natural world in europe and providing an informed and readily accessible encyclopaedia of information (e.g. streble & krauter, ; fitter & manuel, ; olsen et al., ; grabow, ; greenhalgh & ovenden, ). within this vast area of knowledge, ponds are widely acknowledged as important habitats for a wide ranges of plant and animal species- however, pond books perse have been inconspicuous until fairly recently. in the united kingdom, the standard guide to ponds was, until the mid- s, the observer's guide to pond life by john clegg which was fust published in (clegg, ). this small pocket guide proudly announced in its preface that: there has long been a need, not only among the general public interested in natural his tory, but also among the ever-increasing number of students taking freshwater biology as an aca- demie subject, for a compact, pictorial guide to the identification of aquatic animais and plants. (clegg, , p. ). today, the situation is changing and the treatment of ponds is becoming more prevalent with textbooks describing the biodiversity, composition and functions of ponds (e.g. bronmark & hansson, ; stoch, ) and practical guides to pond management ( e.g. williams et al., ; wissinger, ; lloyd & alexander, ). however, we would strongly argue that more needs to be done to raise the awareness of ponds and the need for their conservation. as part of this process there is an urgent need to transmit recent research findings into a language understandable by ail stakeholders-whether they are politicians, farmers, planners, school children, amateur naturalists or the general public at large. the threats to ponds are well known (oertli et al., ; epcn, , ; nicolet et al., ) and, over the past years, several projects at local, regional and european scales have been undertaken to address the principal issues. these initiatives have helped to restore, create, or improve pond manage- ment techniques and to advise stakeholders about the value of these small water bodies. more recently, the emphasis of these projects has moved towards habitat and species recovery and mitigation measures (e.g. ruhi et al., , ; antôn-pardo & armengol, ; gallardo et al., in press; becerra-jurado et al., ). in northern and central europe, a number of projects have seen a large number of ponds created to reinforce amphibian populations (e.g. stumpel & van der voet, ; baker & halliday, ; briggs, ; rannap et al., )-and this is a very positive new development. nevertheless, it can be argued that a more rigorous scientific framework for pond creation is still required (williams et al., ). another situation that has improved in the last decade is the management and protection of temporary ponds in the mediterranean region. severa! authors have established the value of mediterranean tempo- rary ponds and the need for urgent action to conserve these high-biodiversity habitats (giudicelli & thiéry, ; quézel, ; boix et al., ; bagella et al., ) and, although a lot of work has been completed ( e.g. life projects in mediterranean continental france, corsica, minorca and v alència; grillas et al., ; fraga et al., ; sancho & lacomba, ) it has not been enough. however, in a scenario of global climate change (gcc) sorne of these threats will continue to grow. few analyses of the effects of gcc on pond biodiversity or the fonction of pond food webs have been published (but see moss et al., ; rosset et al., ; rosset & oertli, ), although for sorne faunal groups from ponds, such as dragon- flies, amphibians or freshwater reptiles, investigations on the effect of gcc do exist (e.g. blaustein et al., ; hassall et al., ; shoo et al., ; sommer et al., ). fourth conference of the european pond conservation network (epcn-berlin conference, june ) after the first epcn meeting in geneva ("con- servation and monitoring of pond biodiversity"; oertli et al., , ), three more congresses have taken place: toulouse ("conservation of pond biodiversity in a changing european landscape"; nicolet et al., ; céreghino et al., ), valència ("pond conservation: from science to practice"; oertli et al., ; miracle et al., ) and, the most recent one in berlin ("eyes of the landscape- the value of ponds in the st century"). the last congress was organised by the epcn and the leibniz centre for agricultural landscape research (zalf), münche- berg, germany, with the support of various partners. during the short time that the epcn has been in existence, the four meetings have attracted an increas- ing number of delegates. the figures of attendance of these four meetings illustrate this trend (table ). however, two weak points have to be commented upon. first, more than a half of the participants at the fourth epcn conference came from on y three countries (fig. ). although the strength of pond research in different countries goes sorne way to explain this trend, at the same time it seems that the epcn needs to make a greater effort to disserninate the value of the network to other regions (such as eastern europe). second, the conference achieved a high scientific level, but it failed to involve many groups of stakeholders. whilst, as scientists, we applaud our research effort, it is vital that we make a greater effort to influence and inform those people who have a direct impact upon the european pond resource. whether they are government officiais, planners, farmers, politicians or school children, we need to be able to provide them with "user-friendly" information which they can understand and apply. in total, the berlin congress included over oral presentations and a sirnilar number of poster presen- tations dealing with a wide range of tapies including: . pond typology, functions, services in landscapes . methods of ecological monitoring and assessment table number of countries, participants and presentations in each epcn meeting countries number of presentations represented participants oral poster geneva toulouse valencia berlin % • oii'm coumrles • slovalda fs:juk % i!el frwa r j bllgium lib pdlnd ｏｾｮ＠Ｐｇ･ｾ＠ fia- l numbe.r of participant& of each cooutry id be last epcn meetidg (berlin. ). uoder be category "other countries" we included tbe counlries wbi.ch were ｲ･ｰｲ･ｾｃｭｴ･､＠ by less than five participaota. 'i'he e oountriea were (œdcred by dec:reasing umber of participants) : ltaly, switzerlmd, norway, nether- lands, hunpry, czech rqlllblic, belarus, swedcn, portugal, morocco, malta, luxembourg, lmia, llenm.t lld austti.a . pedogenesis and paloolimnology of ponds . hydrology, biogeochemistry, pollution of ponds s. habitat functions, biodiversity, bioindication . practical use. conservation, management of ponds . decision aids for policy, legislation, pond users . education on pond function.ing, values, wise use in addition, tbree wotbhops wcre hcld (wl: ponds as sentinel systems for envirolldlcntal impacts, w : state and perspectives of pond research and conserva- tion in germany, w : role of fish ponds) and two excursions were also offered, auracting a high leve! of participation. this special issue of hydrobiologia contains a selection of contributions pœsented during the conference. a second selection of manuscriptb will be published in a special issue of the journal limnologica undcr the title: "eyes of european landscapes - value, traits, conservation and ｾｮｴ＠ of ponds". spedallssue content like previous selections of manuscripts for the epcn proceedings, the present proceedings demonsttate the strong relationship between scientific research and "management". it is important to emphasise that scientific research projects do not only produce tools and knowledge requested in management; at the same time, man.agement projects present good opportunities to carry out scienti.fi.c studies. l'hus, some of the selected manuscripts have a clear practical objective (e.g. teissier et al., this issue), others are basic research studies whose results are needed to improve management strategies (e.g. jeffries, this issue) and the rest represent basic research performed in the ftamework. of management projects (e.g. orteils et al., this issue). as a consequence of the implementation of the habitats directive and the water fr:amework direc- tive, an important number of faunal and floral invcdlories, water body typologies, bioassess:ment techniques and moditoring programmes have been generated in the last decade in european community countries. although ponds have received less attention than other aquatic ecosystcms, mainly because thcir sizes are not covered by the wfd, this situation has led to proposais for management tools and protocols. in tum, these proposais bighlight some of what is needed to develop the objectives of both directives: preserving wtlkr quality and prioriruing conservation actioru. some of those requirements are to establish a typology of ponds, to identify reference site charac- terlstics, and to improve k:nowledge of environmental species preferences. three manuscrlpts of the present selection treat these aspects. céréghino et al (this issue) compared the biological traits of macroinverte- brates in different biogeographical regions on a european spatial scale (the western meditcrranean, central europe and britain are included), whi.lst: lischeid & kalettk.a (this issue), on a more reduced spatial scale (northeast germany), developed a clas- sification scheme for kettle holes. reference sites are difficult to identify in europe due to high human pressure on aquatic environments. for this reason. information from ne.ighbouring areas is important to avoid the degradation of sites and know their value, but also could help to identify characteristics of well- prese.rved sites and degradation processes. the work ofrhazi. etal. (this issue) assessed poolloss in a region of morocco and identi.fied. the main obstacles to the conservation of the plant ricbness of these pools. pond biodiversity loss bas been one of the earliest concems since the creation of the epcn. few studies have thoroughly analysed pond biodiversity pro- cesses: they have not only overlooked the gain-loss balance in terms of the number of ponds, but also the historical context. i.e. when they were created or destroyed. jeffries (this me) performed a comprehensive analysis of this historical process in a region of the uk and compared the plant biodiversity of severa! types of ponds created in different historical moments for different social purposes. the previously mentioned manuscript by rhazi et al. (this issue) also offered a good approach in this sense. knowledge of community temporal patterns (i.e. colonisation and succession) pro vides the ecological framework needed to interpret the processes that took, are taking or will take place in a pond or in a pond network, and that have to be considered to reverse the present day scenario ofbiodiversity loss. in this sense, ortells et al. (this issue) analysed the importance of founder effect, natural selection and genetic drift during the daphnia magna colonisation process in newly created ponds in spain. moreover, bosiacka & pieri.kowski (this issue) explored how the characteristics of ponds (i.e. size) or pond networks (i.e. connectivity) determine the mac- rophyte species richness in ponds located in poland. management improvements such as tool creation, measures of methodological effectiveness, and the evaluation of the results of monitoring programmes or management experiments were also published in this selection. peretyatko et al. (this issue) developed an efficient cyanobacterial bloom risk assessment tool for ponds in brussels, whilst teissier et al. (this issue) and de backer et al. (this issue) evaluated phytoplankton- nutrient relationships and the probability of fish recolonisation, respectively, after a biomanipulation project carried out in ponds also located in brussels. in addition, florencio et al. (this issue) compared the suitability of two sampling techniques to detect species richness and patterns of diel activity. finally, two of the manuscripts develop suitable conservation strategies to protect pond flora and fauna or provide necessary information to develop them. sumberova et al. (this issue) analysed historical and recent data on tillaea aquatica l. in the czech republic, characterised its habitat, studied the seed bank and seed dispersal, and suggested management measures aimed at promoting the survival of this species. on the other hand, dolgener et al. (this issue) identified management units for conservation of the bombina bombina (l.) populations in an area of eastern germany using a genetic approach. these selected manuscripts are a faithful represen- tation of the high diversity and quality of the presentations of the fourth epcn meeting, and are a sample of sorne of the new insights into pond research and management promoted by the epcn. the fifth epcn conference, to be held in in luxembourg, will be a new step in the enlarging of the network to ali european states and to ali pond stakeholders. acknowledgments w e wish to thank the sponsors of the fourth european pond network meeting (german limnological society, leibniz institute of freshwater ecology and inland fisheries, university of applied sciences neubrandenburg, and bund "friends of the earth"). references Âlvarez-cobelas, m. a., c. rojo & d. g. angeler, . mediterranean limnology: current status, gaps and the future. journal of limnology : - . ammann, k., . la vida a les aigües dolces. teide, barcelona. ant n-pardo, m. & x. armengol, . zooplankton commu- nity from restored peridunal ponds in the mediterranean region (l'albufera natural park, valencia, spain). li- mnetica : - . arévalo, c., . la vida en las aguas dulces. labor, barcelona. bagella, s., m. c. caria & v. zuccarello, . patterns of emblematic habitat types in mediterranean temporary wetlands. comptes rendus biologies : -- . bagella, s., s. gascon, m. c. caria, j. sala & d. boix, . cross-taxon congruence in mediterranean temporary wet- lands: vascular plants, crustaceans, and coleopterans. community ecology : - . baker, j. m. r. & t. r. halliday, . amphibian colonization of new ponds in an agriculturallandscape. british herpe- tological society : - . batzer, d. p. & s. a. wissinger, . ecology of insect com- munities in nontidal wetlands. annual review of ento- mology : - . batzer, d., r. b. rader & s. a. wissinger (eds), . inver- tebrates in freshwater wetlands of north america: ecology and management. wiley, new york. becerra-jurado, g., r. harrington & m. kelly-quinn, . a review of the potential of surface flow constructed wetlands to enhance macroinvertebrate diversity in agricultural landscapes with particular reference to inte- grated constructed wetlands (icws). hydrobiologia. doi: . /s - - - . biggs, j., a. corfield, d. walker, m. whitfield & p. williams, . new approaches to the management of ponds. brit- ish wildlife : - . blaustein, a. r., l. k. belden, d. h. oison, d. m. green, t. l. root & j. m. kiesecker, . amphibian breeding and climate change. conservation biology : -- . boix, d., j. sala & r. moreno-amich, . the faunal com- position of espolla pond (ne lberian peninsula): the neglected biodiversity of temporary waters. wetlands : - . bosiacka, b. & p. pierlkowski, . do biogeographie parameters matter? 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[ - ( ) ; - ] resumen: a partir de la importancia que adquirió en la inglaterra victoriana delimitar los estereotipos de género, se analiza el debate surgido en las postrimerías del siglo xix y muy especialmente en los colleges oxonienses, cuestionando el modelo imperante de hombría representado por el prototipo del gentleman. dicha disputa estuvo avalada por nuevas tendencias estético-artísticas presentes en textos impor- tantes de autores como walter horatio pater, john addington symonds y oscar wilde. este debate posibilitó la apertura de espacios subversivos de creación y ruptura en los cánones hegemónicos de masculinidad regidos por un esquema binario según el cual el género determinaba la única orientación sexual posible, circunscrita dentro de los límites de la heterosexualidad. palabras clave: belleza, cuerpo, pedagogía de la masculinidad, gentleman, dandi, esteticismo. abstract: ever since the importance acquired in the victorian age to define gender stereotypes, the authors analize the debate emerged in the last period of the nineteenth century and especially in the oxonian colleges, questioning the prevailing model of manhood represented by the prototype of the gentleman. this contention, supported by new aesthetic-artistic trends and focused on the texts of authors like walter horatio pater, john addington symonds and oscar wilde, made possible a © ediciones universidad de salamanca hist. educ., , , pp. - issn: - sort of new open-mindedness and a rupture of hegemonic masculinity ideals governed by a scheme where gender binary determined sexual orientation, leaving it, circumscribed to the limits of heterosexuality. key words: beauty, body, masculinity pedagogy, gentleman, dandy, aestheticism. la lectura de la autobiografÍa de lord chesterton nos descubre unaimagen de la época victoriana bien alejada de las connotaciones de lo quehoy en día se identifica como victoriano. de hecho, para el prolífico pensador inglés, la época tuvo todos los vicios que hoy se llaman virtudes: duda religiosa, desasosiego intelectual, hambrienta credulidad ante todo lo nuevo y una total ausencia de equilibrio. también tenía todas las virtudes que hoy se llaman vicios: un gran sentido de lo romántico, un apasionado deseo de que el amor entre hombre y mujer volviera a ser lo que fue en el edén y un poderoso sentimiento de la absoluta necesidad de encontrar un significado a la existencia humana . a todo ello debemos añadir la importancia que adquirió, en el período estu- diado, la necesidad de delimitar los estereotipos de género. hablamos de conceptos normativos expresados en doctrinas religiosas, educativas, artísticas, científicas, legales y jurídicas, con el fin de afirmar, categórica y unívocamente, el significado de varón o mujer y su correspondiente ideal de masculinidad o femi- nidad. así, en el intento de hacer de lo abstracto concreto, se fue estableciendo un esquema binario según el cual, del mismo modo que a todas las personas se les asignaba forzosamente un género, también se consideraba necesario deter- minar una sexualidad. en definitiva, los individuos debían controlar su apariencia y conducta en concordancia con una identidad sexual naturalmente dada que a la vez prescribía la orientación sexual, quedando, ésta, circunscrita en los límites de la heterosexualidad. se trataba, pues, de una identidad normativa con vocación hegemónica que no permitía alternativas. aun así, y como trataremos de reflejar a lo largo de este escrito, las aportaciones sobre qué era y cómo debía comportarse el auténtico gentleman, cuál era su ideal de belleza y cuáles, sus virtudes y deseos, abrieron un interesante debate —generador de subjetividades— cuyas coordenadas espacio- temporales las podemos situar en los colleges oxonienses durante las postrimerías del siglo xix. dicho debate, focalizado en los textos de autores como walter horatio pater, oscar wilde o john addington symonds, entre otros, posibilitaron la apertura de espacios subversivos de creación y ruptura de las definiciones hegemónicas del género masculino. por supuesto que, en su intento, estos intelectuales, forjados en las aulas de la universidad de oxford, fueron desacreditados y expuestos a burlas y difamaciones; o, aún peor, juzgados y condenados a trabajos forzados, como en el caso de oscar wilde. chesterton, gilbert keith: autobiografía, barcelona, acantilado, , pp. - . giddens, anthony: la transformación de la intimidad. sexualidad, amor y erotismo en las socie- dades modernas, madrid, cátedra, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo anglicanos y católicos. una cuestión de género en el momento de abordar las disputas sobre el prototipo de masculinidad del último tercio de siglo, y si nos centramos en los discursos de las distintas institu- ciones antes mencionadas, no podemos obviar cómo los credos religiosos católico y anglicano, a fin de afianzar su poder institucional, o tal vez para lograr la super- vivencia de una doctrina antaño perseguida, se esforzaron por definir los valores y virtudes que debía poseer el auténtico christian gentleman. en semejante empeño axiológico, no resulta difícil descubrir que sus doctrinas, en este punto, se limi- taban a una cuestión de género. en efecto, miembros de la iglesia anglicana como charles kingsley ( - ) no escatimaban esfuerzos por mancillar y desacreditar el movimiento de oxford, también conocido como el tractarian movement. fue éste un movimiento que contó con la presencia activa de john henry newman ( - ), convertido al catolicismo en , y cuyo propósito residía en recuperar las tradiciones de una anhelada iglesia primitiva, en la que el celibato, la vida en común de hombres en hermandades y el consiguiente enaltecimiento de la amistad masculina resultaban elementos cruciales en la determinación de su identidad eclesiástica. estas convicciones no siempre fueron comprendidas, ni mucho menos acep- tadas, desde las filas anglicanas, que, con tal de afianzar y legitimar su doctrina, recurrieron a una vehemente y constante campaña de descrédito de los postulados romanos utilizando las temáticas de género como instrumento de deslegitimación. la cuestión residía en concebir el catolicismo mediante atributos femeninos, con lo que su fe quedaba estigmatizada como débil y enfermiza. además, los máximos representantes del catolicismo, los clérigos, eran tachados de poco viriles e incluso de homosexuales . así lo deja entrever el propio charles kingsley al expresar su aversión hacia las doctrinas amparadas por el concilio de trento: in all that school, there is an element of foppery—even in dress and manner; a fasti- dious, maundering, die-away effeminacy, which is mistaken for purity and refinement; and i confess myself unable to cope with it, so alluring is it to the minds of an effemi- nate and luxurious aristocracy; neither educated in all that should teach them to distin- guish between bad and good taste, healthy and unhealthy philosophy or devotion . en lo tocante a los postulados sobre el ideal de masculinidad, encarnado bajo el prototipo del gentleman, las divergencias entre católicos y anglicanos son nota- bles. para el cardenal john newman, que coincidió con thomas arnold en el oriel college de oxford, todo caballero debe «[...] poseer un intelecto cultivado, un gusto exquisito, una mente sencilla, equilibrada y desapasionada, y un compor- tamiento noble y cortés en los asuntos de la vida» . tal y como sugiere david hilliard en su artículo «unenglish and unmanly: anglo-catholicism and homosexuality», durante el período estudiado —momento crucial en la configuración de la iden- tidad homosexual— se pueden encontrar muchos vínculos entre la literatura homosexual y algunos seguidores de la religión católica. hilliard, david: «unenglish and unmanly: anglo-catholicism and homosexuality», victorian studies, winter ( ), pp. - . kingsley, charles: charles kingsley: his letters and memories of his life, vol. i, london-new york, mcmillan and co, , p. . newman, john henry: discursos sobre el fin y la naturaleza de la educación universitaria, pamplona, eunsa, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo contra la idea de hombre católico, liberal, exquisito, sencillo y desapasionado defendido por newman, el ya mencionado charles kingsley —licenciado en cambridge, e impulsor del muscular christianity junto a thomas hughes ( - )— promovió un prototipo de hombre cristiano caracterizado por el thumos. nos referimos a un hombre fuerte, corpulento, valeroso, un gentleman con gran agresividad física, enérgico, con espíritu fiero, lleno de vigor, y cuyo deber —circunscrito dentro de los márgenes de la heterosexualidad— era la procreación dentro del matrimonio. con objeto de expandir y hegemonizar su ideal de hombría, acorde con las tesis evolucionistas, kingsley publicó un sinfín de novelas de alto contenido didác- tico dirigidas al público infantil y juvenil . novelas como westward ho! dan fe de cuáles han de ser los atributos del auténtico christian gentleman: una mens fervida in corpore lacertoso (mente ardiente en un cuerpo musculoso). por tanto, el caballero kingsleano, convertido en un ejemplar perfecto de la «raza» anglosa- jona, defenderá su tierra y sus ideales sin renegar de su fe anglicana. nos encon- tramos, por consiguiente, ante un héroe hiperviril, un muscular gentleman que debe cuidar su cuerpo, el cual —como si de una máquina se tratara— había de mantenerse fuerte, musculoso y limpio. en el mismo sentido y gracias a los postulados de darwin y spencer, el cuerpo adquirirá una nueva visibilidad . es así como el principio griego de la kalokaga- thia, esto es, lo bello como paradigma de bondad, vino a focalizarse en los cuerpos, generando, a finales del siglo xix, una nueva representación de lo que había de ser una sociedad ordenada, sana y progresista . la convergencia del evolucionismo con los escritos de platón —estudio obligatorio en el currículum de oxford desde destacamos la figura de thomas hughes, por ser el autor de una de las novelas juveniles más populares de la época: tom brown’s schooldays, escrita el , y vertida al castellano en . con el propósito de divulgar los ideales del movimiento cristiano, esta bildungsroman narra el proceso de formación del protagonista a través de la práctica deportiva instaurada en las public schools después de las reformas de thomas arnold. otro de los escritos de hughes, especialmente relevante respecto a la construcción de la masculinidad y sus relaciones con la fe anglicana, lo hallamos en su obra titulada the manliness of christ ( ). el motivo del libro, reflejado en su introducción, no es otro que legi- timar la masculinidad de todos aquellos hombres cristianos involucrados en movimientos sociales. y es que después de veinticinco años de la fundación del movimiento muscular christianity y de la proli- feración de otras agrupaciones religiosas como el young men’s christian association, hughes percibe en muchos sectores sociales la creencia de la falta de hombría y coraje tanto de los responsables como de los discípulos de estas instituciones. hughes, thomas: the manliness of christ, boston, houghton, osgood & company, , p. . la tradición de la literatura infantil en las islas británicas se remonta al siglo xviii. según d. escarpit, el inglés john newburry fue el primer editor especializado en literatura infantil y juvenil, publicando en un libro de bolsillo para este público. también cabe mencionar al editor marshall, que publicó entre y setenta libros infantiles. bassa, ramón: «libros y lecturas para jóvenes. (la trasmisión de valores a través de la literatura infantil y juvenil: el caso de la lij catalana - )», historia de la educación. revista interuniversitaria, n.º - ( - ), p. . constatar como el cuidado corporal posee una trayectoria histórica anterior a la ilustración y al liberalismo del siglo xix. vilanou, conrad: «higiene, deporte y humanismo en el renacimiento español», historia de la educación. revista interuniversitaria, n.º ( ), pp. - . nótese cómo, para muchos intelectuales de la época, la idea de «progreso» significaba la urgencia de leer más griego y, por tanto, menos latín. de ese modo, la apreciación de la importancia del estudio de los clásicos helenos se materializó progresivamente en los currícula de las public schools; cfr. jenkins, richard: the victorians and the ancient greece, oxford, basil blackwell, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo , y en las public schools en el último cuarto de siglo— resultó ser un factor decisivo, no únicamente para promover la exaltación de la supremacía masculina, sino también, la admiración de su belleza corporal. carne y mármol. el homoerotismo victoriano gracias al arte y la literatura, la generación de un nuevo discurso en el que el hombre se tornaba objeto de deseo y de contemplación estética, permitió la reac- tivación de una pedagogía del eros que, bebiendo de las fuentes del ideal de paideia elaborado por platón, empezaba a cuestionar las estructuras binarias que patologizaban y anatematizaban el deseo por una persona del mismo sexo al esti- marlo contrario a la ley natural. será walter horatio pater ( - ), considerado el padre del esteticismo, quien, en su intento por ofrecer una alternativa al ideal hegemónico de masculi- nidad, articuló en su itinerario educativo la necesidad de promover en sus estu- diantes el gusto por la belleza masculina. porque, tal y como sugería platón en el banquete o el fedro y recogía pater, cada alma humana es capaz de entrever en cada cuerpo individual la forma de la belleza que lo impregna. esta inclinación y apetito hacia los cuerpos bellos deviene, para el fellow del brasenose college, el epicentro del self-development —versión inglesa de la bildung germánica— puesto que, sin el impulso y el entusiasmo inagotable de las fuerzas irracionales del hombre, jamás será posible la transfiguración suprema que el espíritu cobra al contemplar la idea de lo bello. en último término, pater proponía hallar nuevas vías de sentir, convirtiendo así la libido en un placer consciente bajo control. por consiguiente, el self-control o self-goverment , se alzaba como el para- digma ético y estético del gentleman pateriano, porque, sin esta rígida disciplina interior, sería imposible una exquisita educación de los sentidos capaz de percibir todos los mensajes de amor y goce que con tantos matices envía el mundo. y es que el objetivo de la vida del hombre, según el discípulo de john ruskin, será «ver cuánto hay que ver, con los sentidos máximamente agudizados. arder siempre sin tasa, con esta llama pura y preciosa, mantener este éxtasis: esto es lo que yo llamo triunfar en la vida» . así, lograr la felicidad, en este mundo en el que todo pasa y nada permanece , vendrá determinado por conseguir atrapar el mayor thomas arnold, headmaster de la escuela de rugby, escribió hacia las siguientes palabras: «aristóteles y platón, y tucídides y cicerón y tácito son llamados muy falsamente escritores anti- guos; realmente son nuestros propios compatriotas y coetáneos», arnold, thomas: ensayos sobre educación, madrid, espasa-calpe, , p. . el autocontrol como excelsa virtud del caballero inglés no únicamente será avalado por pater, sino también por personajes tan relevantes y de ideales tan dispares como el ya mencionado cardenal newman, el crítico de arte john ruskin, o el poeta e hijo de thomas arnold, mathew arnold, quien, como inspector escolar, fue responsable de la introducción del sistema tutorial en las public schools. palabras extraídas del prólogo de la novela escrita por pater —considerada una bildungsroman— mario el epicúreo, traducida por primera vez al español en a cargo de agustín esclasans; pater, walter: mario el epicúreo. sus sensaciones y sus ideas, barcelona, ediciones lauro, , p. . la famosa cita de heráclito es recogida por pater en la conclusión del estudio sobre el renaci- miento. pater, walter: el renacimiento. estudios sobre arte y poesía, barcelona, alba editorial, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo número posible de sensaciones fugaces y sentirlas intensamente antes de que se desvanezcan. el fin que se perseguía con ello no era tanto el fruto de la expe- riencia sino la experiencia misma. en el fondo, lo que se proponía era una clara trasgresión epistemológica: la contemplación del hedonismo y el arte como formas alternativas de conocimiento. criticado como vindicador de un exacerbado hedo- nismo pagano, lo cierto es que pater activa una pedagogía de la experiencia que, gracias al autocontrol, pretende elevarse sobre aquel placer primario o carnal y conducirlo hacia un goce estético que culminará en un intenso amor hacia la filo- sofía, las ciencias y el arte. de igual modo, su profunda identificación con los ideales clásicos llevaron a walter pater a revisitar las corrientes neoclásicas alemanas de la mano de autores como johann joachim winckelmann ( - ) y friedrich schiller ( - ), responsables ambos de promover un nuevo cambio en los paradigmas estéticos de la época. así, durante el siglo xviii, de la antigua roma con su clasicismo barroco se había pasado a la admiración de la «noble simplicidad y serena grandeza» —precepto acuñado por el propio winckelmann— donde la calma, el orden y la mesura reflejaban este universo helénico siempre idealizado. como expondremos a continuación, la recuperación del pensamiento de winc- kelmann sobre el arte clásico supuso, para el crítico inglés, hallar un refugio de pureza y sensualidad en medio de un mundo cada vez más mecanicista y homó- fobo. y es que el autor de reflexiones sobre la pintura y escultura de los griegos ( ) y la ilustrada historia del arte antiguo ( ) propiciaba un ejercicio de sublimación erótica. un ejemplo entre tantos se desprende de su descripción del apolo de belvedere, donde las formas bellas y los bien definidos contornos del mármol hecho cuerpo despiertan en el humanista germano pulsiones sexuales mostrando, de forma explícita, la atracción entre hombres. naturalmente, este homoerotismo apoyado en el culto a la belleza de los antiguos griegos ofrecía una coartada ideológica para librarse de ataduras moralizadoras y privilegiar el poder de los sentidos . un siglo después, las ideas del considerado creador de la historia del arte fueron revisadas por walter pater en su polémico trabajo sobre el renacimiento publicado en bajo el título studies in the history of the renaissance . en la obra, compuesta por diversos ensayos reelaborados una y otra vez a lo largo de los últimos veinte años de su vida, aparecen figuras entonces poco conocidas como boticelli o pico della mirandola, que comparten protagonismo con winckelmann o burckhardt en un intento por desentrañar el significado del arte y la cultura en la vida del hombre. se observa, pues, cómo a lo largo de la extensa obra del esteta forjado en oxford, existe un intento de elaborar una pedagogía de la masculinidad basada sala, rosa: el misterioso caso alemán. un intento de comprender alemania a través de sus letras, barcelona, alba editorial, , p. . considerado como una traición no solo a la sociedad inglesa sino también a los estándares de masculinidad, el libro de pater creó una fuerte convulsión entre sus coetáneos reflejada, por ejemplo, en las palabras de w. t. courthope, que en escribió: «in common, we believe, with most englishmen, we repudiate the effeminate desires which mr. pater, the mouthpiece of our artistic “culture”, would encourage in society», adams, james eli: «gentleman, dandy, priest: manliness and social authority in pater’s aestheticism», english literary history, vol. , n.º ( ), p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo en una relación pedagógica de claros tintes homoeróticos , en la que esa suerte de paideia individual platónica define la formación de un joven a cargo de un educador mayor, sabio y generoso, responsable de guiar al efebo hacia la exce- lencia en la nobleza de espíritu . esta apertura de espacios liberadores fruto de las interpretaciones de los textos platónicos por parte del propio walter pater, pero también de reconocidos oxonienses como symonds o wilde, llegaron a configurar un discurso alternativo, enfrentado al modelo institucional pero, curiosamente, surgido de las mismas insti- tuciones . la gran paradoja del helenismo oxoniense, como advierte dowling, consistió en un sinsentido denunciado por el propio john addington symonds: la universidad revelaba la pederastia, pero después condenaba a discípulos y tutores por imitarla . el desprecio de la sociedad puritana hacia el platón decadente, esto es, hacia la imagen estereotipada de un platón que en el último cuarto del diecinueve amaba y deseaba a los hombres, unido a una fuerte censura social y universitaria, proba- blemente llevaron a pater a no explicitar la consumación del deseo carnal entre educador y educando; si bien es cierto que, en la obra del autor británico, el amor físico entre hombres aparece siempre de forma sutil, tras un velo que sólo los iniciados podrán descubrir . a modo de ejemplo, expondremos las palabras vertidas en un estudio sobre leonardo da vinci, publicado en como parte integrante de el renacimiento. estudios sobre arte y poesía: «[...] el modo en que leonardo elegía a sus discípulos, que siempre eran jóvenes de gran encanto y agra- dable trato como salaino, o nobles de costumbres principescas como francesco melzi; todos ellos dispuestos a sacrificar su individualidad por amor a leonardo y con el suficiente genio para iniciarse en sus secretos» . en un contexto semejante, tampoco sorprende que uno de los máximos expo- nentes de belleza masculina alabados por pater fuera la figura del andrógino. un personaje tan ambiguo como su prosa, repleta de dobles sentidos y significados como advierte alan bloom, la historia del pensamiento occidental está en gran parte constituida por una inestimable historia de relaciones pedagógicas o pederastas entre hombres; cfr. bloom, alan: el cierre de la mente moderna, esplugues de llobregat, plaza & janés, . otros estudios también dan cuenta y se cuestionan las relaciones entre la pedagogía y la pederastia como el polémico trabajo de rené scherer la pedagogía pervertida, publicada en españa en por la editorial laertes. la fascinación de pater por esta relación educativa se refleja en la siguiente cita extraída de su estudio sobre platón publicado el año : «the beloved and the lover, side by side […] became a respectively, […] the hearer, and […] the inspirer, the older inspiring the younger with his own strength and the noble taste of things», pater, walter: plato and platonism: a series of lectures, london, macmillan and co., , p. . como informa patricia cruzalegui, en el último cuarto de siglo, la vertiente sexual del plato- nismo era tan conocida por las clases cultivadas —en especial de oxford— que el término platónico formaba parte de un argot cotidiano que hacía las veces de pederasta; cfr. cruzalegui, patricia: la experiencia platónica en la inglaterra decimonónica, oviedo, septem ediciones, , p. . dowling, linda: hellenism and homosexuality in victorian oxford, london, cornell univer- sity press, , p. . david delaura describe la emergencia de un nuevo prototipo de lector, joven y culto, formado mayormente en los colleges oxonienses, susceptible de una pragmática capaz de sintetizar la sensibi- lidad homoerótica; cfr. delaura, david: «reading inman rereading: a rewiew essay», the pater newsletter, n.º ( ), pp. - . pater, walter: el renacimiento. estudios sobre arte y poesía, op. cit., p. . el subrayado es nuestro. © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo ocultos y situado en los márgenes de las convenciones sobre masculinidad avaladas por la clase media victoriana. androginia y homosexualidad. la subversión de la identidad cuestionando la estructura socialmente codificada de la sexualidad, la vanguardia estética victoriana divisará en el andrógino la piedra de toque para salvar la división entre los sexos mediante el culto a la belleza. como sugiere g. l. mosse, a finales del xix el andrógino representaba la juventud, la gracia y la hermosura al servicio de una identidad sexual constantemente variable en contra- posición con el binarismo cerrado y excluyente avalado por unos discursos cientí- ficos cada vez más legitimados por las estructuras de poder. en efecto, a la pregunta de michael foucault, planteada en el prólogo de la versión americana de los recuerdos de herculine barbin, de si verdaderamente tenemos la necesidad de un sexo verdadero, el filósofo francés pone de manifiesto cómo las sociedades del occidente moderno han respondido afirmativamente . prueba de ello es que durante siglos se admitió que un hermafrodita tuviera dos sexos; pero hacia el siglo xix la medicina y la justicia exigieron obstinadamente una identidad legítima, pues no cabía la posibilidad de confusión en torno al sexo. la apremiante necesidad de fijar una identidad sexual así como sus perver- siones propició la emergencia de un conocimiento cada vez más estructurado sobre la sexualidad que se refleja en la aparición de la sexología como ciencia . asimismo, el deseo hacia las personas del mismo sexo fue reprimido cada vez con mayor energía y, por consiguiente, con mayor visibilidad. paradójicamente, ese intento por nombrar, explicar y definir este nuevo tipo de criatura —la persona homosexual— propició la generación de una nueva categoría, la de la persona heterosexual. nos encontramos, entonces, con un omnipresente hermafrodita (considerado un fenómeno de la naturaleza, una aberración que la ciencia había de estudiar con mosse, george: la imagen del hombre: la creación de la moderna masculinidad, madrid, thalasa, , p. . foucault, michel: «el sexo verdadero», herculine barbin llamada alexina b., madrid, edito- rial revolución, , pp. - . el término sexology aparece por primera vez el año en un estudio realizado por la ameri- cana elisabeth osgood goodrich willard; se trata de un ensayo sociopolítico con tintes antroposó- ficos cuyo objeto era «the revolution and reform of society conformity with natural sexual law [...] it shows the perfect equality of the laws of sex, and also their great dissimilarity», cfr. osgood, elisa- beth: sexology as the philosophy of life: implying social organization and government, chicago, j. r. walsh, , prefacio. tendremos que esperar hasta para la aparición del primer estudio clínico fundamentado en la sexología. nos referimos a la obra psicopatía sexualis, resultado de las investiga- ciones del doctor de la universidad de viena richard von krafft-ebing ( - ), responsable de la clasificación de las prácticas sexuales en normativas y no normativas. krafft-ebing, richard: psychopathia sexualis mit besonderer berücksichtigung der conträren sexualempfindung: eine klinisch- forensische studie für Ärzte und juristen, stuttgart, ferdinand enke, . en el parlamento británico elabora un marco legal para castigar los actos de sodomía. hasta entonces la ley sólo sancionaba la conducta inapropiada en aspectos públicos. después de la ley, cual- quier trasgresión podía ser perseguida, y una cláusula especial expresaba la prohibición de la unisexua- lidad masculina. © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo objeto de poder otorgarle un sexo genuino) compartiendo protagonismo con el mito del andrógino , un prototipo ideal ya referenciado en el banquete de platón, y vuelto a codificar una y otra vez mediante el arte y la literatura: desde las famosas telas pintadas por leonardo da vinci ( - ), como san juan bautista o la virgen de las rocas, pasando por algunos poemas y cuadros del polifacético william blake ( - ) o las ilustraciones de aubrey vincent beardsley ( - ), hasta la figura de séraphita, protagonista de la novela homónima de honoré de balzac ( - ) escrita en . esta obra constituyó un referente para los autores británicos, tanto por su concepción de la belleza como por el hecho de haber considerado los atributos marcadamente femeninos del andrógino como paradigma de plenitud masculina. así, el autor francés presenta esta figura simbólica como un ser de perfección sublime debido a la reconciliación de los opuestos y en la que «la belleza, la elegancia de la vida de la mujer ha sido traspasada al hombre. cuando el hombre no ha conseguido reunir esta belleza, esta elegancia en su vida, es severo, triste y arisco. cuando las ha reunido es de carácter jovial y completo» . la sensibilidad, la sofisticación y la delicadeza —considerados valores esencialmente femeninos y, por tanto, marcados con un halo de negatividad— reviven en el ideal andrógino recuperando su valía. Éstas serán las virtudes que walter pater supondrá indispensables en el momento de articular su ideal del artista como andrógino desarrollado en el ensayo diaphanéite ( ). porque a su entender, y compartiendo las mismas premisas que años después plasmará el poeta rilke en una de sus epístolas, en los hombres hay también maternidad y alumbramiento cuando crean desde su plenitud más íntima . además, este ser delicado y diáfano, de inclasificable pureza, se identifi- cará —siempre según pater— con la belleza suprema, elevándose y superando el bello cuerpo de la mujer. mientras las características femeninas son ensalzadas en el mito del andrógino, la patologización y supuesta inferioridad del hombre homosexual venían determi- nadas por la creencia de que se trataba de una identidad con indicios de femi- nidad . y es que la categoría moderna de la homosexualidad, según m. foucault, se caracterizó no tanto por un tipo de relaciones sexuales como por cierta cualidad de la sensibilidad sexual. la homosexualidad fue rebajada de la práctica de la sodomía a una suerte de androginia interior, un hermafroditismo del alma. el sodomita era un relapso, el homosexual constituirá una especie . sin embargo, la capacidad del carácter productivo de los discursos para conformar subjetividades planteada por el filósofo galo, queda muchas de las veces mircea eliade hace referencia a la fusión primera en el mito de la creación de los hombres ya atestiguada por platón, poniéndola en relación con la tradición bíblica de la caída, interpretada como una dicotomía del hombre primigenio. eliade, mircea: mefistófeles y el andrógino, madrid, col. omega, , pp. - . de balzac, honoré: louis lambert; les proscrits; séraphita, paris, michel lévy frères, , p. . rilke, rainer maria: cartas a un joven poeta, madrid, alianza, , pp. - . así queda reflejado en la ya citada obra psicopatía sexualis del psiquiatra alemán richard von krafft-ebing, quien considera la atracción por el mismo sexo como una patología de inversión puesto que un hombre que se siente atraído por otro era un varón con una psique de hembra y, por tanto, se estimaba como inferior. foucault, michel: historia de la sexualidad, madrid, siglo xxi, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo en entredicho al constatar las constantes fugas y desenmascaramientos de las normas morales y estéticas por parte de aquellos individuos que no reconocían una identidad sexual impuesta, o por la de aquellos que simplemente se revelaban contra un camino ya marcado. Éste es el caso de john addington symonds ( - ), formado en el balliol college de oxford, discípulo de benjamín jowet, destacado poeta, crítico lite- rario, y conocido por ser el responsable de una de las primeras apologías de la homosexualidad en inglés titulada a problem in greek ethics ( ). diez años más tarde escribirá como continuación a esta obra de , a problem in modern ethics ( ), dirigida especialmente a psicólogos y juristas, con el objetivo de demostrar que la homosexualidad podría ser congénita y, por tanto, no punible por la ley y ajena a cualquier tipo de neurosis. por supuesto, tampoco podemos obviar su incursión en el campo de la psicología sexual con su obra sexual inver- sion ( ) en colaboración con havellock ellis , quien finalmente asumió la autoría de la obra. destacar, también, su obra el renacimiento en italia ( - ) considerada uno de los estudios fundamentales de la historiografía moderna. en ella se revelan los matices, las tendencias, las personalidades, los acontecimientos y el despertar de una cultura que, como ya concibiera pater, debe al helenismo el redescubri- miento del propio hombre y de su estar en el mundo. igualmente, gracias a las memorias publicadas después de su muerte, cono- cemos sus relaciones con otros hombres aun estando casado y siendo padre de varios hijos. también, en su devenir, se refleja la conmoción que le supuso la lectura del compendio poético leaves of grass escrito por el estadounidense walt whitman ( - ) . una poesía de claras connotaciones homoeróticas , repleta de optimismo y alabanzas hacia aquellos hombres rudos y trabajadores, cuyos cuerpos musculosos y belleza varonil ejemplificaban su ideal de masculinidad. la energía expresada en los versos del poeta nacido en el condado de suffolk, cuando apuesta por la idea de la amistad viril y noble, aporta a symonds la fuerza havelock ellis es otra figura relevante que pertenece a los círculos científicos de la época victo- riana. médico y psicólogo, protagonista de una tormentosa y tempestuosa vida sexual, fue autor de una obra enciclopédica en seis volúmenes titulada studies in the psychology of sex, publicada entre y . con motivo del escándalo del procesamiento de oscar wilde ( ) afirmó que la homose- xualidad y la heterosexualidad pueden ser naturalmente complementarias y no contrarias. como ellis, y en contraposición a la idea imperante del momento de una homosexualidad considerada como una enfermedad, andré raffalovich, formado en oxford y convertido al catolicismo en , fue el respon- sable de un sinfín de estudios sobre el tema en cuestión. en uranisme et unisexualité: étude sur diffe- rentes manifestations de l’instinct sexuel ( ) argumentaba que tanto la heterosexualidad como la homosexualidad son dos legítimas manifestaciones de la sexualidad humana. asimismo, destacamos de la ingente obra de este autor, trabajos como: l’éducation des invertis ( ); john addington symonds ( ); des mariages entre hommes ( ) o l’amour homosexuel ( ). un vasto conocimiento de la vida y obra de walt withman se refleja en el estudio publicado en por el propio j. symonds y titulado walt whitman. a study. jerome loving, en su obra walt whitman. the song of himself, analiza los sentimientos homo- eróticos de withman. en concreto, la revisión de los manuscritos del poema «live oak» llevan a loving a sugerir la homosexualidad del poeta: «he dreams of a homosexual utopia (“the city of robust friends”) and addresses its ideal lover. such feelings, he now insists, are natural, yet there is also “something fierce and terrible” in them», loving, jerome: walt whitman. the song of himself, berkeley, university of california press, , p. . hay versión castellana, loving, jerome: walt whitman: el canto a sí mismo, barcelona, paidós, . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo para revelarse, de manera explícita y contundente, contra aquellos discursos que, empeñados en taxonomizar la subjetividad emocional, convierten al homosexual en un grupo cuya supuesta homogeneidad estriba en su feminidad. las siguientes líneas, extraídas del libro the memoirs of john addington symonds. the secret homosexual life of a leading nineteenth-century man of letters, atestiguan su férrea negativa a aceptar la teoría del alma femenina de aquellos hombres que, como él, se sienten atraídos por individuos del mismo sexo: i should certainly be tabulated as… on… who is not marked by an effeminate passion for robust adults or by a predilection for young boys… i do not recognize which justifies the theory of a female soul. morally and intellectually, in a character and taste and habits, i’m more masculine than many men. i know who adore women. i have no feminine feeling for the males who rouse my desire. the anomaly of my position is that i …am stirred to the sexual sensations exclusively by persons of the male sex . para finalizar este apartado, nos hacemos eco de la constante generación y coexistencia de discursos dispares e incluso opuestos que, surgidos a finales del ochocientos, han cohabitado y permanecido en el imaginario colectivo hasta tiempos bien presentes. hacemos alusión tanto a la idea antes enunciada de la transitividad de género, atribuida a los homosexuales por haber sufrido una tras- mutación de los caracteres masculinos en femeninos, con la formación de una orientación sexual independiente de los niveles relativos de masculinidad y femi- nidad. la referencia a symonds nos ha permitido hablar del hombre homosexual que parece y actúa como un heterosexual, un hombre diferente a otros hombres en ningún otro aspecto más que en su sexualidad . dandis y gentlemen. la masculinidad como performance el desenmascaramiento de los valores victorianos, la apertura hacia las nuevas tendencias continentales y el revival de ciertas actitudes del período de la regencia caracterizan un fin de siècle inglés en el que la figura del dandi se alzó como uno de los iconos centrales del período . se trata de un prototipo de hombre que aparece en las etapas de transición, cuando la aristocracia ha perdido ya su fuerza y la democracia no la tiene todavía. y es que según baudelaire el dandi «es el symonds, john addington: the memoirs of john addington symonds. the secret homosexual life of a leading nineteenth-century man of letters, new-york, random house, , p. . halperin, david: one hundred years of homosexuality and other essays on greek love, new york, routledge, , pp. - . g. k. chesterton ya confirma al dandi como personaje de la regencia. el dandismo, además, como fenómeno social y político, repercutirá fuertemente en el mundo de las ideas, así como en la configuración de un nuevo ideal de masculinidad. más aún, el lord inglés destaca como característica intrínseca de este prototipo varonil su fascinación por la moda: «el sombrero alto era la última palabra del dandismo exagerado de la regencia, y los petimetres llevaban pantalones, mientras que los hombres de trabajo seguían usando calzón corto. en los pantalones, probablemente hay cierto contagio de orien- talismo; y ya los últimos romanos los veían como un afeminamiento oriental». chesterton, gilbert keith: pequeña historia de inglaterra, p. , http://www.shu.edu/catholic-mission/upload/pequena- historia-de-inglaterra.pdf (consulta de noviembre de ). © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo último destello del heroísmo de las decadencias» . como actitud vital, el dandismo es la personalización de una rebelión contra los estándares de moralidad y decoro de una sociedad determinada. en este sentido podemos considerar que el dandi no pertenece al siglo xix ni al mundo occidental; es más, personajes tan dispares como alcibíades o petronio comparten protagonismo con el duque de lauzun, aristócrata de la corte de luis xiv que, según las referencias de otro famoso dandi como barbey d’aurevilly , se distinguía por su sangre fría, su dominio de sí mismo y el carácter imprevisto de su comportamiento, haciendo tambalear las estrictas normas de etiqueta de la época. sin embargo, es en tierras británicas donde la figura del dandi adquiere fama y reconocimiento gracias a george bryan brummell ( - ) y al poeta lord byron ( - ). posteriormente, el movimiento simbolista francés, con charles pierre baudelaire ( - ) y el escritor y periodista jules amédée barbey d’au- revilly ( - ) —autor de la biografía de brummell— asentaron y explotaron el concepto del dandismo tanto en su vida como en sus obras. pero, sin duda, el hombre que elevó la tradición del dandi hasta su máximo apogeo fue oscar wilde, considerado l’enfant terrible de las letras británicas. naturalmente, para comprender el porqué de la adopción de este modus vivendi por parte del autor de salomé, debemos trasladarnos al oxford del último cuarto de siglo. es en esta universidad, como ya se ha explicitado más arriba, donde las nuevas tendencias estético-artís- ticas de la época generaron un intenso debate llegando, incluso, a deconstruir los rígidos estándares de masculinidad. wilde permanece en oxford desde hasta , y, tal como refleja a lo largo de su obra, la estancia en esta universidad representó uno de los principales momentos de su vida —la cárcel sería el otro—. entre los muros góticos y la imagen de platón compartiendo vidriera con el profeta amós en la capilla del mansfield college, las dos corrientes estéticas oxonienses, auspiciadas por john ruskin ( - ) y walter pater, influyeron sobremanera a un joven wilde, que ya en estos años empezaba a crearse un personaje. la tendencia encabezada por el patriarca del socialismo estético, john ruskin , entroncaba con el romanticismo y los principios amparados por la hermandad prerrafaelita, algunos de cuyos pintores, como dante gabriel rossetti ( - ) o edward burne-jones ( - ), expresaban su rechazo por el arte académico, fomentando la búsqueda de un arte nuevo en conexión con las grandes obras medievales y renacentistas. baudelaire, charles; de balzac, honoré y barbey d’aurevilly, jules amédée: el dandismo, barcelona, anagrama, , p. . barbey d’aurevilly, jules amédée: «un dandi anterior a los dandis», en el dandismo, barce- lona, anagrama, , pp. - . las palabras de marcel proust sobre este poeta y crítico de arte inglés —al que compara con goethe, por su empeño en unir ciencia y arte en su incansable búsqueda de la verdad— nos informan, por un lado, de la dificultad de encasillar a este prolífico autor, y, por otro, de la importancia que éste le otorga a la belleza: «de tantos aspectos de la fisonomía de ruskin, el que nos resulta más familiar, porque es del que poseemos, si puede decirse así, el retrato más estudiado y más adecuado, el más impactante y más extendido, es el ruskin que no conoció en toda su vida más que una religión: la de la belleza [...] sin embargo, esta belleza a la que consagró su vida no fue concebida por él como un objeto de placer y encantamiento, sino como una realidad infinitamente más importante que la vida, por la que hubiera dado la suya propia», proust, marcel: «john ruskin», en días de lectura, madrid, santillana, , pp. - . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo compartiendo protagonismo con esta visión romántica marcadamente autóc- tona, la tendencia encabezada por walter pater, junto al poeta algernon swin- burne ( - ) —introductor de baudelaire en inglaterra—, representaba la corriente del simbolismo de raíz francesa. ambos autores, pilares del decaden- tismo que triunfó en los años noventa, representaban la versión británica de l’art pour l’art, el paganismo, la búsqueda de la intensidad de las pasiones y los pecados exquisitos . la pasión por la italia medieval y la preocupación e interés por los problemas sociales que a lo largo de su vida manifestó oscar wilde nos sitúan en los para- digmas ruskineanos, mientras que la exaltación del helenismo, la búsqueda del placer, la concepción del arte como amoral o el disfrute de todas las sensaciones vendrán marcados por la doctrina de walter pater . pero wilde irá más allá, llevando todos los ideales del profesor del brasenose college a la práctica: el goce corporal y de la mente como aspiración de plenitud, así como la asunción del dandismo como filosofía de vida y como temática en sus escritos. la inclusión del dandi en obras como la importancia de llamarse ernesto ( ) o el retrato de dorian gray ( ) responde, por tanto, a las influencias del esteti- cismo del maestro pater. en relación con esta concepción del dandismo consistente en hacer de la vida una experiencia estética, debemos recalcar la voluntad del autor de hacer confluir obra y vida bajo un mismo prisma. porque tal y como nos hace ver l. a. de villena en su estudio preliminar a la obra de-profundis, en wilde «la creación literaria ilustra la vida, no como aspiración deseada ni como manifestación de un mismo arte. vida y obra se comprenden en la misma esfera» . de hecho, si retomamos una de sus obras más emblemáticas, el retrato de dorian gray, las palabras de wilde ratifican la cita del poeta madrileño: «it contains much of me in it. basil hallward is what i think i am; lord henry what the world thinks me; dorian what i would like to be —in other ages, perhaps—» . sin duda, la tríada de personajes se funden en un oscar wilde que, aun identi- ficándose con el personaje de claras tendencias homoeróticas como el pintor basil hallward prendado por la belleza del joven dorian, reconocemos, también, en el dandi lord henry su teoría estética decadente claramente representada por el libro que éste le regala a dorian gray. nos referimos a la novela del simbolista fue algernon swinburne, adalid de la vanguardia estética decadente, quien exhibió en su obra una compleja naturaleza de lo perverso y lo grotescamente inaceptable, en su intento por cuestionar la moral victoriana. un claro ejemplo es su novela lesbia brandon, considerada por alberto cardín una bildungsroman con tintes autobiográficos. swinburne, algernon charles: lesbia brandon, barcelona, laertes, , p. . destacar de esta novela sentimental su aura masoquista que enlaza con la tradición flagelística inglesa a la que, posteriormente, se refiriera ian gibson como el «vicio inglés», haciendo referencia a los castigos corporales de las public schools; cfr. gibson, ian: el vicio inglés, barcelona, planeta, . a pesar de su esnobismo o de su amor por la élite, wilde demostró su preocupación por las capas más humildes. el ensayo publicado en the soul of man under socialism, confirma su asun- ción del anarquismo avalado por peter kropotkin, exiliado desde hasta en inglaterra y fundador del periódico anarquista freedom. después de la muerte de pater, wilde declaró que la obra el renacimiento. estudios sobre arte y poesía, «has had such a strange influence over my life», de villena, luis antonio: wilde total, barce- lona, planeta, , p. . de villena, luis antonio: prólogo a wilde, o.: de-profundis, barcelona, fontamara, , p. . hart-davis, rupert (ed.): selected letters of oscar wilde, oxford, oup, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo francés j. k huysmans titulada À rebours ( ), cuyo personaje des esseintes personifica al dandi esteta cuya rebeldía se caracteriza por su cinismo y perver- sidad moral. por último, no podemos negar un cierto narcisismo en el propio wilde que, como dorian, rinde culto a la juventud y la belleza mientras muestra una casi enfermiza obsesión por la apariencia física. llegados a este punto, analizaremos la versión sui géneris del dandismo adop- tada por wilde. pero a fin de lograr una mayor comprensión de este fenómeno que en las postrimerías del siglo xix alcanzó múltiples definiciones y equívocos, creemos oportuno trazar una sucinta comparativa entre las concepciones de baudelaire y las del propio wilde. comparten los dos autores ese sentimiento de alineación relacionado con el surgimiento de la ciudad como fenómeno de expansión capitalista. de ahí, la nece- sidad del dandi moderno de una ascesis autoimpuesta adoptando una filosofía basada en el artificio. el culto al yo, como el eje vital, devendrá condición nece- saria para alcanzar la distinción y la originalidad. el dandi, por ende, utilizará la moda, ya que necesita de la vestimenta para expresar su propia anarquía. no obstante, esta obsesión por la propia imagen no debe confundirse con la superfi- cialidad, pues como ya advirtiera el propio baudelaire: «el dandismo no es tampoco, como tantas personas poco reflexivas parecen creer, un gusto inmode- rado por el tocador y la elegancia material. tales cosas no son para el perfecto dandi más que un símbolo de superioridad de su espíritu» . si hasta aquí el concepto del dandismo es compartido tanto por baudelaire como por el propio wilde —recordar su autodenominado «traje estético» como expresión de una apasionada revolución contra las convenciones—, lo que el francés había comenzado en toda su seriedad, oscar wilde lo terminará, apunta moers , en un exceso. efectivamente, lo que impregna la filosofía del francés será la desesperanza y el fracaso, dada la imposibilidad de alcanzar el éxito social de un dandi que, atacando vehementemente a la sociedad en la que se encuentra inmerso, es también consciente de su nula capacidad de integración. como dirá a. ballesteros, la postura estética del dandismo auspiciado por baudelaire impli- cará un proceso de autoextrañamiento y marginación voluntario . por el contrario, el dandi encarnado por el inglés vive en y para la sociedad victoriana; porque, aunque wilde aparentemente reniegue de la hipócrita y puritana moral de su tiempo, la necesitará para reafirmarse y reflejarse en ella, siendo, los demás, el espejo que su egolatría necesita para vivir y crear. pese a estas contradicciones que le empujaron a llevar una doble vida, no debemos menoscabar cómo, en su representación del dandi, wilde no hacía otra cosa que alejarse del gentleman como ideal hegemónico de masculinidad. porque el dandi, imaginado a través de la metáfora de la máscara o del puro espectáculo, se encarnaba en un cuerpo que acabaría siendo todo artificio. por el contrario, el prototipo del gentleman avalado por las clases burguesas vino a representar la de balzac, honoré; baudelaire, charles y barbey d’aurevilly, jules: op. cit., p. . moers, ellen: the dandy. brummell to beerbohm, lincoln, university of nebraska press, , p. . ballesteros, antonio: «los retratos de oscar wilde: el escritor en la sociedad victoriana de fin de siglo», estudios ingleses de la universidad complutense, madrid, edit. complutense, n.º ( ), pp. - . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo idea del unself-conscious, otra manera de decir que en él todo era natural, no había nada forzado en su quehacer. en otras palabras, mientras el gentleman confor- mará su subjetividad en función de las imágenes de hombría socialmente acep- tadas, el dandi, desobedeciendo las normas genéricas, reinventará una nueva masculinidad. por tanto, esta figura pondrá de manifiesto la estructura paródica y teatral del género. más aún, si concebimos el género desde los postulados de la teórica postfemi- nista judith butler, descubriremos una entidad sin base ontológica, regida única- mente por la estética, es decir, una identidad débilmente constituida en el tiempo y establecida por una repetición estilizada de los actos. así, la base sobre la que se articula el género es una pura imitación, una performance carente de origen, y sujeta, como hemos puesto de manifiesto a lo largo de este ensayo, a sus propias insubordinaciones . será fácil comprender, entonces, el tenaz intento de regular unos gestos y un comportamiento como propios y naturales, dada la obsesión victoriana por delimitar, legislar y aumentar su jurisdicción. una obsesión que, por otro lado, favoreció una mayor visibilidad y emergencia de distintos cánones de masculinidad en clara oposición al modelo imperante. del mismo modo, esa mayor visibilidad propició, también, la articulación de lo que podríamos llamar una educación de la mirada. nos referimos a una mirada —siempre historizada— de individuos cada vez más competentes para leer los cuerpos a fin de detectar la otredad. así, mientras el gentleman tendrá un cuerpo; el dandi, el homosexual, o la mujer, es decir, el «otro» será un cuerpo. un cuerpo no normativo que, como expresa paolo zanotti, es un cuerpo observable, sexualizado, socialmente inapro- piado, independientemente de que se ostente la diferencia (como es el caso de los dandis) o se imponga (como sucede con los homosexuales) . el rechazo y la condena impuesta a oscar wilde responden a un cúmulo de circunstancias que no únicamente pivotan sobre sus relaciones homosexuales, y es que, además, el autor del fantasma de canterbury era socialista, irlandés y dandi. demasiada alteridad para una sociedad como la victoriana que no estaba prepa- rada para aceptar abiertamente la diferencia. convencidos de la voluntad de muchos individuos de no sucumbir a la norma- lización, entendemos a virgilio piñeira cuando en su testamento rezaba: «como he sido iconoclasta me niego a que me hagan estatua; si en la vida he sido carne, en la muerte no quiero ser mármol» . sin duda, vivir y escribir desde la disidencia comporta este riesgo que walter pater, john addington symonds y oscar wilde, entre otros muchos, estuvieron dispuestos a correr. butler, judith: el género en disputa. el feminismo y la subversión de la identidad, barcelona, paidós, , p. . zanotti, paolo: gay, la identidad homosexual. de platón a marlene dietrich, madrid, turner publicaciones, pp. - . laudo, xavier: «pedagogía de la carne. la escritura de sí en virgilio piñeira», en moreu, Ángel c. y prats, enric (coords.): la educación revisitada: ensayos de hermenéutica pedagógica, barcelona, publicacions i edicions de la universitat de barcelona, , p. . © ediciones universidad de salamanca hist. educ., , , pp. - la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano raquel cercÓs i raichs y Ángel c. moreu calvo la subversiÓn del gentleman. cuerpo y belleza en el ethos victoriano anglicanos y católicos. una cuestión de género carne y mármol. el homoerotismo victoriano androginia y homosexualidad. la subversión de la identidad dandis y gentlemen. la masculinidad como performance what can the study of culture tell us about disability published in british journal of visual impairment january . an advertising aesthetic: real beauty and visual impairment dr david bolt centre for culture and disability studies, liverpool hope university email: boltd@hope.ac.uk abstract: this paper considers critical responses to disability in twentieth-century anglo- american advertisements from which a problematic advertising aesthetic emerges. the aesthetic is used to test the progressiveness of a recent trilogy of dove advertisements that represents visual impairment. the conclusion is that, while there has been much progress, the ableist advertising aesthetic of decades ago remains an issue in the twenty-first century. more specifically, the dove advertisements are found to be underpinned by ocularcentrism, despite their apparent appreciation of visual impairment. introduction so emotively has disability been represented in literature, film, music, art, and casual conversation that it has now become irresistible to many advertisers. though relatively few, there have been enough critical studies of disability in twentieth-century advertising for an aesthetic to be drawn. this ableist aesthetic is summed up in the present paper in relation to distortion; alterity; disclosure; segregation; and exclusion. the aesthetic is then used as a model of representational regression against which a recent trilogy of dove advertisements is measured. the advertisements all feature women who have visual impairments and refer to visual impairment explicitly. the trilogy is deemed progressive in relation to alterity and segregation, complex in relation to disclosure, but regressive in relation to distortion and exclusion. the trouble is that the apparent appreciation of visual impairment is underpinned by an ableist and more specifically ocularcentric advertising aesthetic. a recent history foundational to this paper, if not to the very discipline of disability studies, are a couple of works on stigma from more than half a century ago. the one, the better known book, was a fairly general study of stigma (goffman, ), while the other focused on disability in particular (hunt, ). the latter made the salient point that disabled people were tired of being represented as pitiable objects whose purpose was to elicit funding, as well as being wonderfully courageous examples to the world, and criticised the stereotyped portrayals of popular culture (hunt, ). this sentiment resonated nearly three decades later when advertising was found to contribute to discrimination in two ways: first, people who had impairments were excluded and in some instances deliberately ignored; and second, a distorted view of disability was presented in order to raise money, as in charity campaigns (barnes, ). the issue of stigma loomed large in advertising because, either way, via exclusion or misrepresentation, for people who had impairments that was the effect. the pitiable misrepresentation of disability was particularly prominent in early charity advertisements. a hallmark of the aesthetic of these advertisements was a stark, usually black and white image of someone who was disabled, with a focus on her or his impairment, the key purpose being to evoke fear and sympathy in the viewer (barnes & mercer, ; hevey, ). unfortunately, until the late twentieth century, the representation of disability in advertising was generally restricted to such fundraising campaigns (brolley & anderson, ), or at best found in medical and rehabilitation product catalogues, disability magazines, and disability organization posters and brochures (thomas, ). representations of disability were seldom included in so-called mainstream advertisements. a more progressive and inclusive approach to disability and advertising became apparent in the late twentieth century. favourable images started to appear in the eighties (longmore, ) and, while ‘routine pictures of disabled people in advertising’ remained ‘hard to find’ (davis, , p. ), a number of advertisements in the early nineties included characters who used wheelchairs and were shown as ‘normal people doing things that normal people do’ (nelson, , p. ). by the end of the century there was a growing list of advertisers who featured disability in their campaigns. this list included crest, citibank, citicorp, coke, fuji, ibm, kmart, levi's, mcdonald's, nissan, pacific telesis, and target (bainbridge, ; fost, ; haller & ralph, ; longmore, ; panol & mcbride, ; shapiro, ; williams, ). thus, by the nineties, if not the eighties, the application of disability in advertising was no longer the sole domain of charity campaigns. the reason for this progress was not simply a less prejudicial, more informed use of images and ideas. the disabled consumer was said to be coming of age, as companies in the united states and the united kingdom recognised the profitability of including disability in their advertisements (haller & ralph, ). this recognition was greatly aided by legislation in the form of the americans with disability act (ada) and the disability discrimination act (dda). moreover, although many businesses started to use disabled models in advertising due to capitalistic motivation (i.e., an awareness not only that there were potential customers who had impairments, but also that diversity enhanced audience reception to the products in question), the crass commercialism produced some good disability images (haller & ralph, ). albeit due to a desire for profits, companies learned to move away from the use of pity narratives and toward advertisements that were sensitive and accurate, that represented disability as ‘another slice of life’ (haller & ralph, ), progress that was bound to reduce stigmatisation. for all this progress, the portrayal of disability in advertising was far from representative, even in purely quantitative terms. advertising images that utilised people who had impairments were ‘few and far between in mainstream media publications’ (thomas, ). indeed, although the united states was faster than the united kingdom to reflect disability in commercial advertising (haller & ralph, ; scott-parker, ), a two-year quantitative analysis conducted in - found that people who had visible impairments were portrayed ‘far less frequently in the commercials than their . % of the population as reported by the census bureau ( )’ (ganahl & arbuckle, ). in relation to britain, advertisements on american television were more prevalent and less restricted (haller & ralph, ) but nonetheless harshly underrepresented people who had impairments. another representational problem related to questions about if, when, and what impairments were shown. the trouble was that impairments in general were avoided; they were conveniently overlooked or else portrayed so as not to intrude on the viewer's aesthetic consciousness (barnes, ; thomas, ). indeed, if and when impairments were visible, they tended to be restricted to a few (if not a couple), for there was an ‘almost total focus’ on wheelchair use and deafness (haller & ralph, ). in other words, in relation to the normative, aesthetic consciousness, some impairments were considered more intrusive than others and avoided accordingly. although the disabled consumer was said to be coming of age, the problem of avoidance extended beyond the advertisements in many ways, even when the medium was relatively easy to make accessible, as in the case of the internet. for example, at the end of the twentieth century, according to one study, three out of four banner advertisements in online newspapers failed to provide accessible content by using an informative alternative to image tags (thompson & wassmuth, ). this state of affairs was worsened by a general lack of concern, a form of critical avoidance (bolt, ), for disability in advertising was an important topic seldom discussed (panol & mcbride, ). indeed, although the scope of mass media advertising campaigns was broad by definition, concern within the academy about this level of misrepresentation was slight (judging by the low number of published papers on the topic). advertising now as we might expect (thanks to disability activism, disability rights, disability advocacy, disability studies, and disability theory), advertising in our own century tends to reflect far more awareness of disability. for example, a qualitative analysis of a selection of anglo- american advertisements since finds improvements in the images of disability, including the theme of empowerment, as used by cingular, and the themes of disability pride and inclusion, as used by doritos, marks & spencer, and hsbc (haller & ralph, ). such advertisements illustrate a departure from the pitiful, sentimental aesthetic used by charities, representations no longer considered appropriate in societies that are trying to restructure themselves so that those of us who have impairments can compete equally in all facets of life (haller & ralph, ). indeed, even charity campaigns now often differ greatly from their problematic predecessors; the use of an ableist aesthetic defined by medical tragedy in order to prompt pity is far less evident. in fact, scope and mencap, among others, explicitly attack disability discrimination in their advertising, and both promote research and campaigns about social exclusion (shakespeare, ). in advertising that utilises disability, then, pity is now far less prominent. but in some of its content, advertising that utilises disability certainly remains problematic. though departing from the more overt pity narratives, several advertisements adopt antiquated themes that continue to stigmatise those of us who have impairments: among others, nuveen, healthextras, and bank of america advertisements convey underlying messages that those of us who have impairments are broken, in need of repair; awash in tragedy; or supercrips, put on pedestals for living our lives (haller & ralph, ). reminiscent of what was carelessly circulated nearly half a century ago, when people who had impairments grew tired of being represented as pitiable or wonderfully courageous (hunt, ), these and other such advertisements follow a binary system in which those of us who have impairments are represented in extreme terms: overtly negative or ostensibly positive. from all this we can gather that there is an ableist advertising aesthetic that still resonates in campaigns that employ disability. the nature of this aesthetic can be summarised in relation to five points: . distortion – usually based on pity, fear, or wonder, a distorted view of people who have impairments is presented; . alterity – routine, slice of life representations of people who have impairments are not used (instead, otherness is constructed); . disclosure – impairments are conveniently overlooked or represented so as not to disrupt the normative aesthetic (alternatively, impairment is such a focus that it becomes reductive and the person effectively becomes displaced); . segregation – advertisements that feature disability or people who have impairments are not used in mainstream campaigns; . exclusion – advertisements that feature disability or people who have impairments are carelessly rendered inaccessible. if only to start the discussion, this problematic profile is a useful instrument in the analysis of recent advertisements, such as those in the dove trilogy. the key is that regurgitation of the ableist aesthetic demonstrates regression, while departure often reveals progress. campaign for real beauty launched a decade ago, the dove campaign for real beauty has its genesis in concerns that portrayals of women and girls in popular culture are helping to perpetuate an idea of beauty that is neither authentic nor attainable (etcoff et al, ). the need for authenticity informs not only the selection of women for the advertisements but also the scenarios that are used, as noted by one of the team that developed the campaign in the first instance: ‘[w]e made a lovely spot with a blind girl to advertise physical deodorant and we could have got her a script and encouraged her to script it, but she is who she is and she talks authentically. and actually, it is manifestly the truth’ (fielding et al, ). the significance of the editing process emerges later in the present paper, but the point to note here is that although the manifest focus of the campaign is the real beauty of real women, it is criticised in many feminist readings (dye, ; froehlich, ; johnston & taylor, ; scott & cloud, ). the fundamental problem is that dove markets itself as an esteem-building brand based on enhancing women’s natural beauty, yet what it sells are beauty products; it is not, therefore, a shining beacon of social change, but a product of corporate aims, implicit in the social problems it seeks to transform (dye, ). in brief, the campaign for real beauty is part of the very social aesthetic by which women become stereotyped and stigmatised. this paper focuses on three dove advertisements that feature women who have visual impairments. the first advertisement, already mentioned, is for deodorant; the second is for the movement for self-esteem; and the third is for hair colour radiance shampoo/conditioner. aired between and , all three advertisements depart from the ableist aesthetic insofar as they do contain slice of life representations and are used in a mainstream campaign, facts that should be acknowledged from the outset. however, in relation to distortion and exclusion the advertisements are far from progressive and even the disclosure of impairment warrants some discussion. the deodorant advertisement shows a woman who is alone but getting ready to go out with her friends. she tells us that she loves this chance to relax and pamper herself, that she finds the whole experience therapeutic. however, she explains, her deodorant and hair spray must be kept apart to avoid confusion between the two, thereby suggesting that, for her, the purely visible labels are not accessible. this hint toward visual impairment is sustained when we are told that the woman chooses her clothes by how they feel, that she has to be especially careful about using deodorant that leaves marks, and that she puts sellotape on the end of her eyeliner so as not to confuse it with lip liner. the woman’s impairment ultimately becomes explicit, though, for she asserts that she does most things by touch since losing her sight. thus, the initial concealment is not simply about protecting the normative aesthetic: it adds punch to the revelation that the woman so preoccupied by looks does not perceive by visual means. the full power of this punch is captured in the critical term aesthetic blindness (bolt, ), which designates the epistemological myth of blindness to aesthetic qualities, whereby visual impairment becomes synonymous with ignorance, and aesthetic qualities are perceived by purely visual means. a consequence of this myth is that aesthetic qualities perceived by other than visual means find expression, indeed legitimation, via visual terms – and, by extension, even the emotions become so framed, as illustrated in the dove trilogy. aesthetic blindness is implicit in the advertisement for hair colour radiance shampoo/conditioner, which focuses on one woman, like the deodorant advertisement, but represents slices, rather than a single slice of life. the woman is shown sitting on a sofa, in the shower, on the beach, in a car, in a boat, in a field, and so on. again, the ableist aesthetic is not disrupted initially, for there are no signifiers of visual impairment until the woman finally says, ‘being blind i can’t physically see the colour of my hair.’ thus, aesthetic blindness is implicit because, as in the deodorant advertisement, visual impairment is concealed for effect, specifically to bolster the revelation that the woman who has so much to say about beauty does not perceive by visual means. the movement for self-esteem advertisement is similar insofar as it begins with a woman on her own but, unlike the others, she is not preoccupied with beauty or how she looks. rather than getting ready for a night out, for example, she is preparing for a game of cricket. the advertisement is also different because instead of concealing her visual impairment in order to reveal it as the narrative unfolds, this woman opens with an explicit reference to when she began to lose her sight. indeed, where concealment is employed creatively in the other advertisements, in this case there may be a charge of reductionism in the emphasis on visual impairment, a danger of ‘reducing the complex person to a single attribute’ (garland- thomson, , p. ). where the trilogy unifies, however, is in ocularcentrism. although the woman in the movement for self-esteem advertisement reassures us that she has found her passion in the sport she plays twice a week, the vast majority of her direct (but obviously edited) speech refers or alludes to vision – and, by extension, visual impairment. if the dove trilogy is complex in terms of disclosure, it is profoundly problematic in relation to distorted representation. most explicitly, the woman in the movement for self-esteem advertisement asserts that when she began to lose her sight ‘it all seemed so dark,’ thereby illustrating an ocularcentric rendering of visual impairment that invokes the fear of darkness in order to elicit pity. far more than pity and fear, however, it is wonder that distorts the dove trilogy’s representation of people who have visual impairments. for example, in the deodorant advertisement the woman says, ‘i don’t know why i use a mirror, i can’t see myself,’ an expression of perplexity that is likely to elicit wonder in the viewer, as the visual domain becomes appropriated by someone who perceives by other means. the use of the mirror resonates with aesthetic blindness, as though beauty must be assessed visually, a suggestion confirmed when the woman finally turns to the camera and asks, ‘do i look fit?’ the importance of the visual assessment of her beauty thereby becomes explicit and the implied audience finds a sense of narrative closure, a release from tensions around any suggested departure from ocularcentric aesthetics. the advertisement for the movement for self-esteem is similarly fixated on vision and employs what is sometimes called an overcoming narrative (mitchell & snyder, ; snyder & mitchell, ). the woman in the advertisement employs ocularcentric language in order to overcome her visual impairment. ‘i found my passion,’ she asserts, ‘i found the light.’ at this point viewers see a sunlit scene that reveals the woman’s passion to be cricket. the visual references continue as she says, ‘i started to see things clearly’ and ‘i don’t let my sight get in the way.’ this contrary reference to ‘sight’ denotes visual impairment, which illustrates the point that ‘if the actions of disabled individuals are cited as the source of overcoming, then it is only to the extent that they successfully distance themselves from the stigma of their own biologies’ (snyder & mitchell, , p. ). the woman’s self-esteem depends on her distancing herself from the stigma of her visual impairment. paradoxically, this narrative about overcoming visual impairment works by rendering the woman’s predicament in visual terms. although the ocularcentric aesthetic ostensibly allows expression of achievement, it necessarily leaves people who have visual impairments wanting. the use of an overcoming narrative is less explicit in the advertisement for hair colour radiance shampoo/conditioner, but the evocation of wonder is nonetheless strong and emanates from the concept of synaesthesia. in a radio programme about this advertisement, the creative director sarah bamford explains that the idea comes from a briefing with dove and a colour psychologist about a test on someone who is blindfolded and yet can feel if colours are cool or warm (in touch, ). indeed, kate crofts, the woman in the advertisement, asserts in the same programme that she is ‘acutely aware of the synaesthesia phenomenon of enjoying and experiencing one sense through another’ (in touch, ). in the advertisement she tells us that colour is sounds, smells, and textures: yellow is sunshine on her face, lemon in her drink; and blue is cool water, air, and sky. she also refers to the pertinence of different colours to different moods, although this point is problematically illustrated via an invocation of stereotypes, whereby blondes are ‘bubbly and fun and girly’ and red hair reveals passion. the supposed significance of colour becomes more dramatic when we are told that even normal things become vivid: ‘it’s like the feeling of the sun on my skin or the wind in my hair’; ‘i feel like laughing and dancing’; and ‘i feel beautiful. it makes me happy and i want it to stay that way because i want to feel like that every day.’ the perception of colour becomes paramount, as though sight is the supreme sense by which the other senses are led. the woman perceives by other than visual means but her very emotions are translated into visual terms. adding the proverbial insult to injury, the dove trilogy is patently problematic in relation to access. despite late twentieth-century legislation, the accessibility of advertising remains an issue for those of us who have visual impairments in the twenty-first century. google adsense, for example, has been found inaccessible because it uses the iframe tag and javascript, and as such prevents many screen-readers from being functional in reading the content (thomson, ). the dove trilogy is comparably inaccessible because there are no audible indications of the products being advertised: in the first advertisement, the product becomes apparent in the form of an image of dove invisible, a deodorant that, according to the writing on the screen, keeps the user’s ‘black dress black’; in the second advertisement, the text reads, ‘dove movement for self-esteem’ and ‘how do you see the world?’; and in the third advertisement, the text reads ‘keep the feeling of freshly coloured hair’ and ‘dove colour radiance’. in the absence of an audible representation of these product names and slogans, the advertisements are essentially inaccessible for those of us who do not perceive by visual means, a scenario that is surely worsened by the fact that the advertisers employ people who have visual impairments and use visual impairment as a theme. after all, the implication is that the advertisers accept the aesthetic blindness implicit in their work and imagine that those of us who have visual impairments necessarily have no interest in a beauty campaign. conclusion this paper considers a number of studies from which an ableist advertising aesthetic emerges. the aesthetic captures half a century of problems with disability in advertising. whatever the advertisers’ intentions, the result has tended to be the stigmatisation of people who have impairments. in the case of the recent dove trilogy, the advertisements are found quite progressive in relation to alterity and segregation, given that they present slices of life and appear in a mainstream campaign. the results of the analysis are less positive in relation to disclosure, owing to the cardinal plot function of visual impairment (whether it be stated at the outset or withheld for dramatic effect). however, the advertisements are regressive in relation to distortion and exclusion, for though not designed to elicit pity or fear, they evoke wonder that is grounded in ocularcentrism and worsened by blatant inaccessibility. the depiction of the pleasure of people who have visual impairments is manifestly positive, of course, but becomes negative when persistently (if not exclusively) expressed in visual terms. if beauty is superficial, as is often said, it becomes even more so when stripped of all but visible content. it has been argued elsewhere that, irrespective of the manifest intention, the campaign for real beauty is part of the social aesthetic by which women become stereotyped and stigmatised. along similar lines, in the present paper, close analysis of the dove trilogy reveals it to be part of the ableist social aesthetic by which those of us who have visual impairments are stereotyped and stigmatised. reference list bainbridge, j. 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( ). disabled people work their way up to tv ads: madison ave. has changed its opinion on what plays in the u.s. retrieved from http://adage.com/article/opinion/disabled-people-work-tv-ads-madison-ave-changed- opinion-plays-u-s/ http://adage.com/article/opinion/disabled-people-work-tv-ads-madison-ave-changed-opinion-plays-u-s/ http://adage.com/article/opinion/disabled-people-work-tv-ads-madison-ave-changed-opinion-plays-u-s/ capri .dvi b physics at cdf – the beauty of hadron collisions d. tonellia∗ afermilab, p.o. box , batavia, il, , usa the cdf experiment at the tevatron pp̄ collider established that extensive and detailed exploration of the b–quark dynamics is possible in hadron collisions, with results competitive and supplementary to those from e + e − colliders. this provides an unique, rich, and highly rewarding program that is currently reaching full maturity. i report a few recent world-leading results on rare decays, cp-violation in b s mixing, and b → s penguin decays. . introduction precise results from the successful b–factories experiments disfavor large contributions from non standard model (sm) physics in tree-dominated bottom meson decays. agreement with the sm within theory uncertainties is also manifest in higher-order processes, such as k –k or b – b flavor mixing. the emerging picture confirms the cabibbo-kobayashi-maskawa (ckm) ansatz as the leading pattern of flavor dynamics. non- sm contributions, if any, are small corrections, or appear well beyond the tev scale (and the lhc reach), or have an unnatural, highly fine- tuned flavor structure that escaped all experi- mental tests to date. the last chances to avoid such a disappointing impasse include the physics of bottom-strange mesons, still fairly unexplored, along with a few rare b decays, not fully probed at the b-factories because of limited event statis- tics. the cdf experiment at the tevatron is cur- rently leading the exploration of this physics, ow- ing to cp-symmetric initial states in √ s = . tev pp̄ collisions, large event samples collected by a well-understood detector, and mature anal- ysis techniques. cdf is a multipurpose mag- netic spectrometer surrounded by π calorime- ters and muon detectors. most relevant for b physics are the tracking, particle-identification (pid) and muon detectors, and the trigger sys- ∗ for the cdf collaboration tem. six layers of double-readout silicon mi- crostrip detectors between . and cm from the beam, and a single-readout layer at . cm ra- dius, provide precise vertex reconstruction, with approximately ( ) µm resolution in the az- imuthal (longitudinal) direction. a drift cham- ber provides samplings of three-dimensional charged-particles trajectories between and cm radii in |η| < , for a transverse momentum resolution of σpt /p t = . %/(gev/c). specific ionization measurements in the chamber allow . σ separation between charged kaons and pi- ons, approximately constant at momenta larger than gev/c. a comparable identification is achieved at lower momenta by an array of scin- tillator bars at cm radius, which measure the time-of flight. muons with pt > . ( . ) gev/c are detected by planar drift chambers at |η| < . ( . < |η| < . ). low-pt dimuon triggers select j/ψ, rare b, and bottomonia decays. they collected approxi- mately millions j/ψ decays in fb− of data, used to reconstruct roughly , b s → j/ψφ, , b → j/ψk∗( ) , and , b+ → j/ψk+ decays. a trigger on charged parti- cles displaced from the primary vertex collects hadronic heavy-flavor decays. it relies on dedi- cated custom electronics to reconstruct tracks in the silicon with offline-like ( µm) impact pa- rameter resolution, within µs of the trigger latency. this yielded approximately millions d → k−π+, , b s → d−s (π+π−)π+, and , b → k+π− decays in fb− of data. fermilab-conf- - -ppd cdf has currently collected fb− of physics- quality data. the sample size will reach fb− in october . additional fb− will be col- lected if the proposed three-year extension will be funded. in the following i report some recent, world- leading results, selected among those more sensi- tive to the presence of non-sm particles or cou- plings. branching fractions indicate cp-averages, k∗ is shorthand for the k∗( ) meson, and charge-conjugate decays are implied everywhere. . polarization in b s → φφ decays the b s → φφ decay proceeds through a penguin-dominated b → ss̄s transition and was first detected by cdf a few years back. we recently improved the measurement of branch- ing fraction using ± events reconstructed in . fb− of data collected by the displaced- track trigger. we obtain b(b s → φφ) = [ . ± . (stat.) ± . (syst.) ± . (b)] × − [ ]. the last uncertainty is due to the uncertainty on b(b s → j/ψφ), used as a reference. three polarization amplitudes enrich the phe- nomenology of the b s → φφ decay. they cor- respond to the allowed values of orbital angu- lar momentum (ℓ = , , or ) in the decay of a pseudo-scalar into two vector particles (b → v v ). a determination of these amplitudes may contribute useful insight into the puzzling pic- ture of b → v v polarizations, where experi- mental data in b (+) → φk∗(+) decays disfavor first-order predictions of small transverse compo- nent (ft = o(m v /m b) ≈ %, where m are the masses), possibly suggesting contributions from non-sm amplitudes [ ]. we report the first measurement of b s → φφ polarization, using the sample employed for the branching fraction measurement [ ]. we fit the mass of the four kaons and their angular distri- butions (in helicity basis). the angular accep- tance, extracted from simulation, is validated by measuring the polarization of b s → j/ψφ decays to be consistent with results from an indepen- dent sample [ ]. the small bias due to decay- length requirements in the trigger is included in the systematic uncertainties. in analogy with measurements of similar b → s penguin decays, the results are at odds with naive theory predic- tions. we measure |a | = . ± . (stat.)± . (syst.), |a||| = . ± . (stat.) ± . (syst.), |a⊥| = . ± . (stat.) ± . (syst.) for the polarization amplitudes, and cos(δ||) = − . + . − . (stat.) ± . (syst.) for the phase difference between the a|| and a am- plitudes. further extensions of this analysis to larger samples will provide information on the decay-width difference ∆Γ in b s mesons. . rare b → µ+µ− and b → hµ+µ− decays decays mediated by flavor changing neutral currents, such as b (s) → µ+µ− or b → hµ+µ− are highly suppressed in the sm because they occur only through higher order loop diagrams. their phenomenology provide enhanced sensitiv- ity to a broad class of non-sm contributions. the b (s) → µ+µ− rate is proportional to the ckm matrix element |vtd| (|vts| ), and is further suppressed by helicity factors. the sm expecta- tions for these branching fractions are o( − ), ten times smaller than the current experimental sensitivity. an observation of these decays at the tevatron would unambiguously indicate physics beyond the sm. or, even improved exclusion- limits strongly constrain the available space of parameters of several susy models. the latest cdf search for b (s) → µ+µ− decays uses . fb− of data collected by the dimuon trigger with pt(µ) > gev/c [ ]. a loose pres- election based on opposite-charge dimuon trans- verse momentum and muon identification criteria (quality of matching with track, energy deposit in the calorimeter, specific ionization energy loss), rejects combinatoric background and charmless b decays. further rejection is achieved by se- lecting on the decay-length significance (λ/σλ) against prompt background and on the isolation of the b (s) meson candidate, to exploit the harder fragmentation of b–mesons with respect to light- quark background. in addition, we require the candidate to point back to the primary vertex to further reduce combinatoric background and partially reconstructed b–hadron decays. the re- sulting event sample contains about , can- didates, mostly coming from combinatoric back- ground. to further enhance purity we use an ar- tificial neural network classifier (nn) that com- bines information from the above observables into a single scalar discriminating quantity. signal dis- tributions are modeled from detailed simulation; backgrounds from mass-sidebands in data. the signal rate is normalized to , b+ → j/ψ(→ µ+µ−)k+ reconstructed in the same sample. the ratio of trigger acceptances between signal and normalization modes (≃ %) is derived from simulation, the relative trigger efficiencies (≃ ) are extracted from unbiased data and the rel- ative offline-selection efficiency (≃ %) is de- termined from simulation and data. the ex- pected average number of background events in the search region is obtained by extrapolating events from the mass-sidebands. the validity of this extrapolation is checked by comparing pre- dicted and observed background yields in sev- eral independent control samples including like- sign dimuons, opposite-sign dimuons with neg- ative decay-length, and opposite-sign dimuons with one muon failing the muon-quality require- ments. small contributions of punch-through hadrons from b (s) → h+h′− decays are included in the estimate of total background. we optimize the limit by combining three independent ranges for the nn discriminator (with efficiencies rang- ing from to %) to obtain the a priori best ex- pected % c.l. upper limit on b(b (s) → µ+µ−) (see fig. ). the resulting ( )% cl upper- limits are b(b s → µ+µ−) < . ( . ) × − , ( ) b(b → µ+µ−) < . ( . ) × − . ( ) these results are the most stringent currently available and reduce significantly the allowed pa- rameter space for a broad range of susy models. an update of this analysis with approximately doubled sample size will further improve them soon. we also updated the analysis of b → k∗ (→ k+π−)µ+µ−, b+ → k+µ+µ−, and b s → φ(→ k+k−)µ+µ− decays to . fb− of data [ ]. these are suppressed in the sm (b ≈ − ), with amplitudes dominated by penguin and box figure . distribution of µ+µ− mass in three independent ranges of the nn classifier. b → s transitions. despite the presence of final- state hadrons, accurate predictions greatly sensi- tive to non-sm contributions are possible for rel- ative quantities based on angular-distributions of final state particles. the b+ and b decays have been previously studied, while the b s channel has not been observed yet. we use a large sample of high-purity dimuon candidates combined in a common vertex with one or two charged particles, whose masses are assigned as appropriate for each final state. in the b decay, the mass hypothe- sis yielding the kπ mass closer to the known k∗ mass is chosen, resulting in the proper assignment about % of the times. a nn that uses informa- tion from kinematics and particle-identification greatly improves signal-to-background discrimi- nation. it is trained on simulated signals and mass-sideband data. the simulation is tuned to reproduce accurately the data using the corre- sponding resonant channels (b → j/ψh). the nn is optimized for maximum expected statisti- cal resolution on the branching ratio and asym- metry measurements. prominent signals of ± b+ → k+µ+µ− and ± b → k∗ µ+µ− events (fig. , left) are observed. the absolute branching fractions, measured using the resonant decays as a refer- ence, are [ . ± . (stat.) ± . (syst.)] × − and [ . ± . (stat.) ± . (syst.)] × − , re- spectively, consistent and competitive with pre- ) ) (gev/c * kµµm( . . . . . . . ) e v e n ts / ( m e v /c - cdf run ii preliminary l= . fb -µ+µ* k→ b ( expected)±yield: mev/c±mass: data total fit signal background ) ) (gev/cφµµm( . . . . . . . ) e v e n ts / ( m e v /c - cdf run ii preliminary l= . fb -µ+µφ → sb ( expected)±yield: mev/c±mass: data total fit signal background figure . distribution of k+π−µ+µ− mass (left) and k+k−µ+µ− (right). vious determinations [ ]. in addition, ± b s → φµ+µ− events are reconstructed, corre- sponding to the first observation of this decay, with a significance in excess of σ. the branch- ing ratio, ( . ± . (stat.)± . (syst.))× − , is consistent with theory predictions, and corre- sponds to the rarest b s decay ever observed to date. we use the b+ and b signals for the first measurement in hadron collisions of branching ra- tios, muon forward-backward asymmetry (afb ), and k∗ longitudinal polarization, as a function of the dimuon mass. the asymmetry is greatly sensitive to non-sm particles and is determined from a fit to the cos(θµ) distributions, θµ being the helicity angle between the µ+ (µ−) and the opposite of the b (b̄) direction in the dimuon rest frame. angular acceptances are determined from simulation. figure shows the asymme- try as a function of dimuon mass. integrated in the – gev /c range, where theory predic- tions are most reliable, it equals afb ( < q < ) = . + . − . (stat.) ± . (syst.), consistent with belle and babar determinations [ ]. cdf plans to achieve world-leading results by summer with the anticipated – factors increase in statistics, due to additional data, triggers, and reconstructed final states. ) /c (gev q f b a - . . . data sm sm =-c c )-µ+µ* k→ (bfba - cdf run ii preliminary l= . fb figure . forward-backward asymmetry in b → k∗ µ+µ− as a function of dimuon mass. . measurement of the b s mixing phase non-sm contributions have not yet been ex- cluded in b s-b s mixing. their magnitude is constrained to be small by the precise determi- nation of the frequency [ ]. however, knowledge of only the frequency leaves possible non-sm con- tributions to the (cp-violating) mixing phase un- constrained. the time evolution of flavor-tagged b s → j/ψφ decays allow a determination of this phase largely free from theory uncertain- ties. these decays probe the phase-difference be- tween the mixing and the b̄ → c̄cs̄ quark-level transition, β j/ψφ s = β sm s + β np s , which equals βsms = arg(−vtsv ∗tb/vcsv ∗cb) ≈ . in the sm and is extremely sensitive to non-sm physics in the mixing. a non-sm contribution (βnps ) would also enter φ j/ψφ s = φ sm s − βnps , which is the phase difference between mixing and decay into final states common to b s and b s, and is also tiny in the sm: φsms = arg(−m /Γ ) ≈ . . because the sm values for β j/ψφ s and φ j/ψφ s cannot be resolved with the precision of cur- rent experiments, the following approximation is used: φ j/ψφ s ≈ − βnps ≈ − β j/ψφ s , which holds in case of sizable non-sm contributions. note that the phase φ j/ψφ s also modifies the decay- width difference between light and heavy states, ∆Γ = Γl − Γh = |Γ | cos(φj/ψφs ), which en- ters in the b s → j/ψφ amplitude and equals ∆Γsm ≈ |Γ | = . ± . ps− in the sm [ ] . we updated the measurement of the time- evolution of flavor-tagged b s → j/ψ(→ µ+µ−)φ(→ k+k−) decays to a sample of . fb− collected by the dimuon trigger [ ]. im- provements over the previous version of the anal- ysis include (a) a doubled event sample along with a newly optimized selection (b) a fully data-driven recalibration of the flavor-tagging al- gorithms (c) inclusion of possible non-φ scalar k+k− contributions as b s → j/ψf ( ). ] ) [gev/cφ ψmass(j/ . . . . . c a n d id a te s p e r m e v /c - cdf run ii preliminary l = . fb - mixing frequency in ps a m p lit u d e - . - . - . . . . . . amplitude a - sensitivity: . ps - cdf run preliminary, l = . fb - mixing frequency in ps a m p lit u d e - . - . - . . . . . . figure . distribution of j/ψk+k− mass after the optimized selection. a kinematic fit to a common space-point is ap- plied to the candidate j/ψ and two tracks con- sistent with being kaons originated from a φ me- son decay. a nn trained on simulated data (to identify signal) and b s mass sidebands (for back- ground) exploits kinematic and pid information for an unbiased optimization of the selection: we minimize the average expected statistical uncer- tainty on the mixing phase extracted from en- sembles of statistical trials generated with dif- ferent input values. discriminating observables used include kaon-likelihood, from the combina- tion of de/dx and tof information; transverse momenta of the b s and φ mesons; the k +k− mass; and the quality of the vertex fit. the fi- nal sample contains approximately signal events over a comparable background (fig. , left). the angular distributions of final state particles provide a statistical determination of the cp- composition of the signal thus improving sensi- tivity to the phase. possible contributions from scalar j/ψk+k− or j/ψf ( ) final states are included in the angular distributions. the pro- duction flavor is inferred using two classes of al- gorithms. opposite-side tags (ost) exploit fla- vor conservation in strong interaction. being b– quarks predominantly produced in pairs with b̄– quarks, the production flavor is inferred from the charge of decay products (e, µ, or jet) of the b– hadron emitted in the opposite hemisphere of the signal b s. same-side tags (sst) exploit flavor conservation in the fragmentation process that leads to the signal b s meson. because a ss̄ pair will be required to form a meson from the bottom quark, the charge of a kaon kinematically close to the bottom-strange meson is correlated to its fla- vor. the performance of flavor taggers is modeled as function of many event properties using simu- lations; however overall scale factors between the simulation and reality are allowed and extracted from data. the uncertainty in their determina- tion contributes to the final systematic uncer- tainty of the measurement. the tagging power, ǫd , is the product of an efficiency ǫ, the fraction of candidates with a flavor tag, and the square of the dilution d = − w, where w is the mis- tag probability. we calibrate independently b and b̄ ost tags using , b+ → j/ψk+ decays. predicted and measured dilutions agree with scale factors close to unity. the observed tagging effi- ciency is ( . ± . )% and the average predicted dilution on signal is √ 〈d 〉 = . ± . , with . ± . scale factor. the sst calibration is obtained by repeating the full mixing analysis on , b s → d−s π+(π+π−) [ ]. the result- ing frequency, ∆ms = . ± . (stat.) ps− , is fully consistent with published values (fig. , right). the scale factor, a = . ± . (stat.) ± . (syst.) is given by the size of the amplitude at the mixing frequency. this corresponds to a tagging efficiency of ( . ± . )% and an aver- age dilution on signal of √ 〈d 〉 = . ± . . multiple tags, if any, are combined as indepen- dent for a total tagging power ǫd ≈ . %. the proper time of the decay and its resolution are known on a per-candidate basis with an average resolution of approximately fs− . information on b s candidate mass and its uncertainty, angles between final state particles’ trajectories (to ex- tract the cp-composition), production flavor, and decay length and its resolution are used as observ- ables in a multivariate unbinned likelihood fit of the time evolution that accounts for direct de- cay amplitude, mixing followed by the decay, and their interference. direct cp-violation is expected small and neglected. the fit determines the phase β j/ψφ s , the decay-width difference ∆Γ, and many other “nuisance” parameters including the mean b s lifetime ( /(Γl + Γh)), the magnitudes of lin- ear polarization amplitudes, the cp-conserving phases (δ‖ = arg(a‖a ∗ ), δ⊥ = arg(a⊥a ∗ )), and others. the acceptance of the detector is calcu- lated from simulation and found to be consistent with angular distributions of random combina- tions of four tracks in data; the fit model was validated by measuring lifetime and polarization amplitudes in b → j/ψk∗ decays to be consis- tent with b–factories measurements [ ]. for enhanced precision, all parameters but the mixing phase are determined in a fit with phase fixed to zero: cτ(b s) = . ± . (stat.) ± . (syst.) µm, ∆Γ = . ± . (stat.) ± . (syst.) ps− , |a||| = . ± . (stat.) ± . (syst.), |a | = . ± . (stat.) ± . (syst.),and δ⊥ = . ± . (stat.) ± . (syst.) rad. these results represent the cur- rent best measurements of these quantities from a single experiment. with phase floating, fits on simulated samples show biased, non-gaussian distributions of esti- mates and multiple maxima, because of known likelihood symmetries. we use a frequentist con- fidence region in the (β j/ψφ s , ∆Γ) plane using a profile-likelihood ratio ordering [ ], which is close to optimal for limiting the impact of sys- tematic uncertainties. these are included by ran- domly sampling a limited number of points in the space of all nuisance parameters. a specific value (β j/ψφ s , ∆Γ) is excluded only if it can be excluded for any assumed value of the nuisance parameters within σ of their estimate on data. the resulting allowed region is greatly reduced with respect to the previous measurement and is fairly consistent ( . σ) with the sm: the range [ . , . ]∪[ . , . ] contains the βj/ψφs phase (rad) sβ - ) - ( p s Γ ∆ - . - . - . . . . . - cdf run ii preliminary l = . fb % cl % cl sm prediction figure . confidence region in the (β j/ψφ s , ∆Γ) plane. at the % cl and the range [-π/ , - . ] ∪[- . , . ]∪[ . , π/ ] at the % cl. with the full run ii data sample, we expect to observe a non-sm phase or exclude it for any value of β j/ψφ s larger than approximately . rad. references . cdf collaboration, note , and d. acosta et al. (cdf collaboration), phys. rev. lett. , ( ). . heavy flavor averaging group, arxiv:[ . (hep-ex)]. . cdf collaboration, note . . cdf collaboration, note , and t. aal- tonen et al. (cdf collaboration), phys. rev. lett. , ( ). . cdf collaboration, note , and t. aal- tonen et al. (cdf collaboration), phys. rev. lett. , ( ). . cdf collaboration, note , and t. aal- tonen et al. (cdf collaboration), phys. rev. d , (r) ( ). . cdf collaboration, note , and a. abu- lencia et al. (cdf collaboration), phys. rev. lett. , ( ). . u. nierste, talk at ckm workshop . . cdf collaboration, note . . d. tonelli (for the cdf collaboration), arxiv:[ . (hep-ex)]. springer a++ viewer publisherinfo publishername : biomed central publisherlocation : london publisherimprintname : biomed central beauty has its cost articleinfo articleid : articledoi : . /gb-spotlight- - articlecitationid : spotlight- - articlesequencenumber : articlecategory : research news articlefirstpage : articlelastpage : articlehistory : registrationdate : – – onlinedate : – – articlecopyright : biomed central ltd articlegrants : articlecontext : william wells email: wells@biotext.com brooks reports in the july nature that male guppies that are sexually more attractive are also evolutionarily less fit (nature , : - ). this may reflect negative pleiotropic effects of genes for attractiveness, such as the energetic cost of creating large amounts of pigments. alternatively, deleterious alleles may be hitching a ride in the region of the y chromosome that has attractiveness genes such as those for color patterns. the increased attractiveness of the male fish ensure the chromosome's genetic survival, but suppression of recombination on the y chromosome means that the deleterious alleles are not weeded out. references . nature magazine, [http://www.nature.com/nature/] this pdf file was created after publication. http://www.nature.com/nature/ references ijn- -current-application-of-phyto-compounds-based-nano-cosmeceuti © ganesan and choi. this work is published and licensed by dove medical press limited. the full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the creative commons attribution – non commercial (unported, v . ) license (http://creativecommons.org/licenses/by-nc/ . /). by accessing the work you hereby accept the terms. non-commercial uses of the work are permitted without any further permission from dove medical press limited, provided the work is properly attributed. for permission for commercial use of this work, please see paragraphs . and of our terms (https://www.dovepress.com/terms.php). international journal of nanomedicine : – international journal of nanomedicine dovepress submit your manuscript | www.dovepress.com dovepress r e v i e w open access to scientific and medical research open access full text article http://dx.doi.org/ . /ijn.s current application of phytocompound-based nanocosmeceuticals for beauty and skin therapy palanivel ganesan , dong-kug choi , department of applied life science, nanotechnology research center, department of biotechnology, college of biomedical and health science, konkuk university, chungju, republic of korea abstract: phytocompounds have been used in cosmeceuticals for decades and have shown potential for beauty applications, including sunscreen, moisturizing and antiaging, and skin-based therapy. the major concerns in the usage of phyto-based cosmeceuticals are lower penetration and high compound instability of various cosmetic products for sustained and enhanced com- pound delivery to the beauty-based skin therapy. to overcome these disadvantages, nanosized delivery technologies are currently in use for sustained and enhanced delivery of phyto-derived bioactive compounds in cosmeceutical sectors and products. nanosizing of phytocompounds enhances the aseptic feel in various cosmeceutical products with sustained delivery and enhanced skin protecting activities. solid lipid nanoparticles, transfersomes, ethosomes, nanostructured lipid carriers, fullerenes, and carbon nanotubes are some of the emerging nanotechnologies cur- rently in use for their enhanced delivery of phytocompounds in skin care. aloe vera, curcumin, resveratrol, quercetin, vitamins c and e, genistein, and green tea catechins were successfully nanosized using various delivery technologies and incorporated in various gels, lotions, and creams for skin, lip, and hair care for their sustained effects. however, certain delivery agents such as carbon nanotubes need to be studied for their roles in toxicity. this review broadly focuses on the usage of phytocompounds in various cosmeceutical products, nanodelivery technologies used in the delivery of phytocompounds to various cosmeceuticals, and various nanosized phytocompounds used in the development of novel nanocosmeceuticals to enhance skin-based therapy. keywords: nanodelivery technologies, skincare, nanophytocompounds, nanophytocosmeceu- ticals, nanotherapy introduction cosmeceutical research is a rapid growing area in personal care sectors, which extends from facial products to skin and body products. – a forecasted report suggested that by , the global market for cosmeceuticals will reach ~ billion dollars and lead to a great demand in near future. even though various synthetic compounds are cur- rently available in the world market, human toxicity is increasing with cosmeceutical interference in certain treatments. – alternatively, plant-derived natural, bioactive compounds show enhanced beauty roles, along with health benefits against diseases. – plant-derived bioactive compounds have been used for centuries in cosmeceuticals for a wide variety of beauty treatments for the skin, face, lips, hair, and nail care with beneficial actions against photoaging, inflammation, hair loss, lip care, psoriasis, and ultraviolet (uv) toxicity. – further, uv radiation causes skin tanning and endothelial cell necrosis and suppresses immunological functions. some natural phytobioactive compounds can prevent these deleterious effects with skin care. , – correspondence: dong-kug choi department of biotechnology, college of biomedical and health science, konkuk university, chungju - , republic of korea tel + fax + email choidk@kku.ac.kr journal name: international journal of nanomedicine article designation: review year: volume: running head verso: ganesan and choi running head recto: phyto-based nanocosmeceuticals for skin therapy doi: http://dx.doi.org/ . /ijn.s in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / http://www.dovepress.com/permissions.php https://www.dovepress.com/terms.php http://creativecommons.org/licenses/by-nc/ . / https://www.dovepress.com/terms.php www.dovepress.com www.dovepress.com www.dovepress.com http://dx.doi.org/ . /ijn.s mailto:choidk@kku.ac.kr international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress ganesan and choi phytobioactive compounds used in cosmeceuticals include catechins, gallic acids, epicatechins, curcumin, hydroxylbenzoic and cinnamic acids, quercetin, ascorbic acids, luteolin, alpha and beta carotene, complex polysaccha- rides, and fatty acids. – these compounds, in addition to their cosmetic effects, enhance antibacterial, antifungal, anti- carcinogenic, and anti-inflammatory biological actions. – even though various macrosized phytobioactive compounds are used in cosmeceutical formulations, their solubility and formulation type have limitations in enhancing the effect of phyto-based cosmeceuticals and therapy. – the major limitations of phyto-based cosmeceutical therapy include less skin penetration, lower prolongevity, less final quality and lower whitening effects. these qualities depend on the solubility and size of the active phytocompounds. , this leads us in search of novel, highly promising technolo- gies for enhanced skin health efficiency of cosmeceutical products. nanotechnology solves most issues with higher protec- tive and skin health-enhancing efficiency. various nano- technology methods are involved in active roles in beauty enhancement, such as nanoemulsions, liposomes, solid lipid nanoparticles, smaller sized nanoparticles, hydro- gels, and dendrimers. , , commercially, many synthetic compounds are used in nanocosmeceuticals that cause toxicity and skin health concerns. natural phytocompounds are in a greater demand. – nanoscale phytocompounds used in cosmeceutical products are gradually increasing among products such as sun screens, antiaging, and uv protectants. – fewer phyto-based cosmeceutical nano- products available in the market are reviewed, namely, vitamin e in acne lotion, tea extracts in nanoshampoo, green tea extracts in the ageless skin care miracle kit, and vitamin e and aloe in uv protection moisture lotion. these phyto-based cosmeceutical nanoproducts contribute to the higher efficacy of the products mentioned for skin-based nanotherapy. , recent studies suggest that phyto-based nanocosme- ceuticals will play a greater dual role in the near future for their enhanced protective, beauty, and health benefits. , , , therefore, the current review focuses on the different types of nanosized cosmeceuticals, current nanotechnol- ogy usage in the development of nanosized compounds or carriers for the delivery of phytobioactive compounds, and various nanosized phytobioactive compounds used in cosmeceutical therapy for their enhanced skin therapeutic applications. phytoconstituent-based nanocosmeceuticals for skin therapy nanoantiaging aging is the critical factor that causes skin collagen to lose its physical appearance in many ways such as oil production decrease, dry skin, texture loss, age spots, and loose skin. aging causes skin thinning, and the end result is wrinkle formation. , this is not limited to the aged population; younger individuals exposed to various harsh environmental conditions such as infrared and ultraviolet rays, chemical pollution, and other physical stresses can also be affected. , currently, various synthetic and natural antiaging creams using nanosize technology are available on the market with enhanced skin protection to moisturize, lift, and whiten skin. – recently, lohani et al reviewed some nanoproducts produced by few companies for enhanced beauty, such as hydra zen cream, revitalift, and skin caviar ampoules that contain phytocompounds, using various nanotechnologies. nanosized phytobioactive compounds, such as curcumin and vegetable oils, show enhanced skin appearance by various antioxidative mechanisms. the aforementioned products prevent skin aging due to oxidative stress and premature aging. – the combination of polyphenols with retinols enhances skin protection. other than nanosizing, few delivery systems have been used to develop nanoantiaging creams and lotions for the enhanced activity of bioactive compounds to deeper layers of skin. recently, a nanoemulsion system was constructed using eysenhardtia platycarpa leaf flavanones with nm nanoparticles that enhanced antiaging activity. polymeric nanoparticles of e. platycarpa leaf flavanones with the particle sizes between nm and nm also showed the enhanced antiaging effects. in addition, coencapsulation of resveratrol and curcumin showed enhanced delivery of phytocompounds for disease treatment with their antioxidant activities and thereby delays aging effects. , nanomoisturizers skin dehydration can be prevented by moisturizers, which support skin beauty and enhance skin flexibility by maintain- ing moisture. a moisture-preventing barrier on the skin is the stratum corneum, which maintains the skin moisture. dehydration results in the abundant loss of water from the skin. moisturizer creates a thin film on the outer surface of the skin maintaining skin moisture and can be effectively achieved by various nanotechnological systems. currently, nanoemulsions, nanoliposomes, and solid lipid nanocarriers are effectively used in moisturizer formulations with active in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress phyto-based nanocosmeceuticals for skin therapy phytoingredients and enhance the skin’s beauty. , further, skin hydration is effectively enhanced with prolonged activity achieved by the solid lipid nanoparticle systems with low vis- cosity and nongreasy effects. currently, many phyto-based nanomoisturizing delivery systems are in starting phases of development. among them, safranol was used in the devel- opment of solid lipid nanoparticles with enhanced moistur- izing effects, along with uv protecting activity. in this system, the minimum nanoparticle diameter was nm. similarly, rice bran oil nanoemulsions were also developed with enhanced moisturizing effects to improve various skin diseases, including atopic dermatitis and psoriasis. opuntia ficus-indica (l.) extract mill nanoemulsions were developed with varying particle size from nm to nm and had enhanced moisturizing effects. currently, various vegetable oil nanoemulsions were studied for their potential use as a moisturizer product. in the future, vegetable oils will be a great alternative for enhanced moisturizing effects for dry skin-related diseases. nanoskin cleanser skin cleanser plays an active role in maintaining skin health. , a thin hydrolipid film covers the skin containing cellular debris from the decomposition products of corneo- cytes and secretions from eccrine, sebaceous, and apocrine glands. hydrolipid films on the skin surface may attract undesirable microorganisms, which in turn accelerate the odor production with the metabolized products from the sweat glands. skin cleaning directly promotes the removal of skin surface bacteria, which reduces odor production. currently, skin cleaning products are available on the market from macro- to nanosize containing both synthetic and natural products. , research is being performed on several phyto-based nanocompounds for enhanced skin cleaning. recently, phyto-based extracts used in cleansers showed enhanced skin cleansing activity by reducing pore size and skin oil content. however, they are only in the budding stage. the effectiveness of using phyto-based compounds in skin cleansing and related to skin disease such as acne is well studied. similarly, nanosized liposomal lauric acid was constructed in the size range of nm and showed enhanced antimicrobial activity against the acne. another study, using niosomes by combination of lauric acid and curcumin, showed enhanced antimicrobial activity against acne-caused skin infections. these studies suggest that phyto-based nanotechnologies show enhanced effects on skin cleanser activity on skin disease. further, phyto-based nanotechnologies will pave the way for the development of skin cleanser products with phytocompounds with enhanced skin cleaning activity. nanosunscreens sunscreens protect the skin from the harmful sun rays exposure. commercially, sunscreens available are in the forms of creams and lotions that contain synthetic compounds, which act as a barrier when the harmful rays hit the skin. sunscreens prevent deep uv ray penetration and inhibit irritation and other consequences. however, synthetic sun- screens have disadvantages, including formation of a chalky layer, greasiness, smelliness, decreased appeal, and toxicity. a few of the mentioned disadvantages are overcome by use of natural phyto-based active ingredients. recently, bulla et al studied the usage of phyto-based bioactive compounds derived from schinus terebinthifolius raddi in sunscreens and found that they enhance antioxidant and sun blocking activities. similarly, bioactive-rich dried extracts of brazil- ian lippia species showed higher photoprotective activity. even though phytobioactive compounds show increased sunscreen effects, their stability and skin protective effects were greatly enhanced by using nanotechnology delivery systems in the sunscreen cream and lotions. , , recently, saffranol was constructed using solid lipid nanoparticles and had enhanced sun screening activity in the size range of – nm. similarly, nanostructured lipid carriers were constructed using rice bran oil and raspberry oil and had enhanced sunscreen activities with higher antioxidant and uv protective activities. in another study, phytoflavanoid- encapsulated poly(lactic-co-glycolic) acid nanoparticles were constructed with the particle size of – nm that had enhanced sunscreen activity along with increased antioxidant activity. in another study, a pomegranate seed oil nanoemul- sion was constructed with various nanoparticle sizes and showed increased skin protection against photodamage with enhanced antioxidant activities. the same research group also studied the effect of pomegranate seed oil nanoemulsions on human erythrocytes and found increased photosafety of lipid skin membranes. the earlier research suggests that the development of novel nanosized phytocompounds will enhance sunscreen products with fewer toxic effects. nanohair care hair care is the most promising cosmeceutical sector. people of all ages are concerned about their hair. hair loss may occur at any age. hair loss conditions are associated with scalp in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress ganesan and choi inflammation and growth disorders, which vary with the individual. – this affects the social status of individuals due to changes in physical appearance of the increased hair loss by vellus follicles transformations. several plant-derived phytobioactive compounds are extensively used in the hair care products. – recently, phytochemicals from rice and artichokes are used to enhance the hair growth, color, and appearance and protect hair from uv-induced degradation. similarly, pomegranate hydroethanolic extract was used in the reduction of the hair follicle red fading effect and enhanced hair color retention. the mixture of phyto-based bioactive compounds also showed enhanced hair growth in the anagen phase. along with hair growth, the phyto-based bioactive compound mixture protects from hair loss and breaking. recently, a nanocosmeceutical-based approach of promoting hair growth was achieved using delivery tech- nologies, such as niosomes and liposomes, to hair follicular cells. – curcumin-based liposomes were constructed and had % enhanced penetration of the curcumin to the hair growth, irrespective of liposomes type in the size range of – nm. similarly, a curcumin-based cyclodextrin complex also showed enhanced follicle penetration and hair growth enhancement. in addition, the combination of polyarginine and oleic acid-modified nanoparticles in size range of – nm showed enhanced skin penetration of follicular or nonfollicular cell pathways. these studies confirm that higher penetration of bioactive molecules from the plants can be enhanced by nanotechnology to develop better hair growth, disease treatment, and beauty therapies. nanonail care nanonail care is a promising novel cosmetic and health care sector. nanonail care particles are developed using synthetic particles and show increased protective effects against nail infections. this treatment increases nail glow and toughness in mammals. , however, the use of synthetic nanoparticles has a decreased market impact compared to natural products. therefore, the demand of phyto-based nail care products is gradually increasing. natural, plant-based pigments mostly consist of phytobioactive compounds and have various therapeutic effects. bioactive compounds from plants are rich in color such as carotene (orange color), chlorophyll (green), and curcumin (yellow), lycopene (reddish orange), anthocyanin (red/purple), and annatto (yellow/orange). these compounds were used in the traditional practices of mixing colored extracts with honey, ghee, or coconut oil for skin and nail care. , these bioactive compounds have antibacte- rial, antifungal, antiviral, and antioxidant health enhancing effects. even though these compounds are used in foods and cosmetics at the macro- or microlevels, the use of the natural pigments at the nanolevel is limited. recently, asynthetic nanoemulsion was developed with enhanced antifungal activity against nail infections. turmeric and henna are rich in phytobioactive compounds, and their role in the nail care is well known. however, the role of nanosized turmeric and henna bioactive compounds remains unstudied. further, during nanosizing, the colors and their effects may enhance or change, which will give future researchers a broad range of the nanonail care cosmetics to study. nanolip care nanolip cosmetics are another growing nanosector. cur- rently, various synthetic and metal particles are used at the nanosize for effective lip protection, enhanced color. these products last longer and have a homogenous distribution. the use of nanometal particles enhances the even distribu- tion of pigments over the lips to increase protection. since lips are most vulnerable skin-type, caution is necessary when using synthetic and metallic nanoparticles. generally, phytoconstituents are used in the lip care at the macro- and microlevels such as coconut oil, curcumin, and other bioac- tive compounds that have increased protective activity. , recently, plant betalains, a novel dietary-colored indole- derived pigments, were efficiently used in the lip care prod- ucts and the extraction of those compounds and their encapsu- lation enhances storage stability – and applications. bixa orellana was used as a colorant for lip jelly and was found to have higher organoleptic lipstick properties. similarly, propolis was also used in the development of a novel lipstick. however, the use of nanotechnology in phyto-based lipstick development is still in the budding stage. phytoconstituent-based nanodelivery systems in cosmeceuticals for beauty and health care limitations of synthetic bioactive ingredients used in cosmeceuticals increase the demand of nanosized phyto- based bioactive ingredients that can be applied by nano- delivery systems. , , , nanodelivery systems enhance the solubility of the active phytobioactive compounds and penetrate through the skin. penetration enhancement of active phyto-based ingredients was achieved through suit- able nanodelivery techniques that led to increased cosme- ceutical effectiveness. , , , , , in addition, phyto-based bioactive ingredients solve most skin diseases, and thereby, nanotechnology enhances the therapeutic value of dual role in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress phyto-based nanocosmeceuticals for skin therapy cosmeceuticals. further, nanoparticle formulation increases retention of the product on the outer skin layer. various nanodelivery techniques used in the formulation of cosme- ceuticals are of solid lipid nanoparticles, nanostructured lipid carriers, liposomes, phytosomes, nanoemulsions, nanonio- somes, nanocapsules, and nanolipospheres. , , solid lipid nanoparticle-loaded resveratrol showed enhanced permeation in the porcine skin. similarly, colloidal silica emulsion loaded with quercetin also showed enhanced human skin per- meation owing to the nanosizing of the compounds. even though various nanotechnology systems enhanced deeper penetration of phytocompounds that are currently available in cosmeceuticals, technology usage depends upon the type of bioactive ingredients, such as hydrophilic or hydrophobic, gel or emulsion, size, degradability, and toxicity. in this section, we discuss the type of nanotechnology delivery techniques used for the development of phytobioactive compound-based nanocosmeceuticals. solid lipid nanoparticles solid lipid nanoparticles are among the nanotechnologies exten- sively used in both pharmaceuticals and cosmeceuticals. , , commercially, many cosmeceutical companies produce cosmeceuticals using this technology to enhance beauty and therapy. this nanoparticle system developed from micro- emulsion systems using solid lipids such as stearic acid, cetyl, and palmitic acid along with plant-derived phytocompounds such as flavonoids, phenolic acids, and other active com- pounds. solid lipid nanoparticles have advantages in stability, higher production, and long-term storage compared to other conventional and nanodelivery techniques. , , , solid lipid nanoparticles also boost the cosmeceutical efficiency by enhancing properties that includes hydration, lower uptake of the systemic circulations, therapeutic values, prolonged, and sustained release in the skin and hair. recently, sesamol- loaded solid lipid nanoparticle was constructed with the par- ticle size of nm for usage in skin cream, which increased the apoptotic nature of the skin. vitamin a-loaded solid lipid nanoparticles were constructed with the particle size of nm and increased skin moisture retention and skin occlusive effects in porcine skin. , similarly, curcumin, another bioactive compound, was constructed using solid lipid nanoparticles with the particle size of nm. this packaging of curcumin showed enhanced activity in hydro- gels prepared for inflammation treatment of porcine skin. however, some solid lipid nanoparticles showed a higher particle size with the addition of quercetin, an average of nm. this size can be reduced with the addition of silica, decreasing the average size to nm causing enhanced skin penetration of quercetin with higher photostability and skin protection. , in another study, caffeine-loaded solid lipid nanoparticles were constructed, with a particle size of nm and enhanced skin permeation of the bioac- tive compound with higher skin protection. similarly, resveratrol-loaded solid lipid nanoparticles with a particle size of nm showed higher skin permeation with enhanced protection. , lutein-loaded solid lipid nanoparticles with the various nanosizes showed increased skin protection from the uv light and antioxidant activity retention, thereby prolonging skin health. from the earlier research studies, solid lipid nanoparticles made with plant-based bioactive compounds suggest that cosmeceutical efficiency and health benefits are increased. solid lipid nanoparticles may promote this sector with further development of phyto-based solid lipid nanoparticle formulations with multiple applications in therapy-based nanocosmeceuticals. nanostructured lipid carriers nanostructured lipid carriers are another important delivery technology used in cosmeceuticals to deliver natural and synthetic bioactive ingredients with increased efficiency. – this technology has more advantages than other nanotechnologies in bulk production, increased sta- bility of the carriers, and is different from solid lipid nano- carriers with the use of liquid lipids such as oleic acid. in addition, nanostructured lipid carrier has different structures such as imperfect type with different lipid structures, form- less type with lipid preventing crystallization, and multiple type with the lipid oil containing bioactive compounds thereby limit the expulsion of bioactive compounds, which is a major drawback in solid lipid nanoparticles. several phytobioactive compounds are highly used in the prepara- tion of nanostructured lipid carriers with high efficiency in the topical applications, thereby protecting the skin and enhancing beauty. okonogi and riangjanapatee recently developed a nanostructured lipid carrier for topical deliv- ery of lycopene with particle size ranging from nm to nm. similarly, a lutein-nanostructured lipid carrier with particle size of – nm was constructed and tested for uv protection in the pig ear skin studies. these studies confirm that the lutein nanoparticle formation and their skin protective effects vary with nanocarrier type. solid lipid nanocarriers showed higher lutein photostability followed by nanostructured lipid carrier and nanoemulsion. moreover, the stability of all three types of nanocarriers showed better photoprotection of the skin. in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress ganesan and choi in another study, a quercetin-loaded nanostructured lipid carrier was constructed with the particle size of nm and showed enhanced topical delivery of bioactive compounds with higher antioxidant activity. this quercetin product enhances the beauty of the skin from preventing oxidative stress. similarly, nanostructured lipid carrier was con- structed using phenylethyl resorcinol with a particle size of nm and showed enhanced photostability and water stability, which may be applied as a whitening agent in the near future. , resveratrol was also constructed using nanostructured lipid carrier systems in the size range of nm and showed enhanced skin protection with higher antioxidant activity, than solid lipid nanoparticle-loaded resveratrol. further e-resveratrol greatly protects skin through the lipid-based nanoparticle system, under uv radiation. in certain studies, some bioactive compounds, such as squalene, promote drug absorption to the hair fol- licles, for example, a squalene-enriched nanostructured lipid carrier with a particle size of – nm is used to treat hair follicles of individuals suffering from alopecia areata. from these recent research studies, we confirm that nanostructured lipid carrier systems will open a gateway for phytobioactive compounds to enhance beauty and personal care. nanosingle or multiemulsions single or multiple nanoemulsions are currently used in various cosmetic products for their specific application using sizes between nm and nm with enhanced activity. , , the major advantages of using nanoemulsions in cosmetics are their unique size, which can enhance the bioactive activity of both hydrophilic and lipophilic types. however, this method has limitations in cosmeceutical production due to instability of emulsions during storage. – further, the emulsion core compounds direct whether a single or multiple nanoemulsions can be formed based on their number of core compounds in the nanosized emulsions. , multiple emulsions have advan- tages over single emulsions, due to their wider applications in cosmeceuticals, which can further reduce cosmeceutical cost. several plant-derived bioactive compounds are used in nano- emulsions, such as flavonoids and polyphenols. their bioactive role enhances cosmeceutical value with lower toxicity. – recently, quercetin-rich nanoemulsions, in the size range of – nm, were prepared from the ethanolic extract of achyrocline satureioides and showed increased skin retention of bioactive compounds with enhanced antioxidant activities in porcine skin studies. in another study, genistein, a soy bioac- tive compound, coloaded with tocomin, acts as multiple nano- emulsions with the particle size of – nm and showed enhanced skin protection from uv damage. this treatment will be useful in the sunscreen lotion production. similarly, retinyl palmitate was used in the production of nanoemulsions in the size range of  nm and showed enhanced skin penetration with increased inner skin protection. similarly curcumin nanoemulsions were developed using a self-nano- emulsifying method with the mean particle size of nm and showed enhanced transdermal availability with high perme- ability and without degradation. this might be useful in the skin care sectors for developing novel skin cream emulsions. in another study, lutein was successfully encapsulated into nanoemulsions in the size range of – nm and increased the release of the active compound compared to other lipid carriers. it showed comparatively better protection than corn oil suspended lutein. nanoemulsions are highly used in skin-based beauty therapy. achyrocline extract nanoemulsions show enhanced protection against herpes virus infections. even though these phytocompound-rich single or multiple nanoemulsions showed better protective effects in various cosmeceuticals compared to commercial macroformulations, the stability of nanoemulsions is a big issue in the production and commercialization of these delivery technologies in the cosmeceutical sectors. lipid-based nanocapsules lipid-based nanocapsules show promising effects in bio- medical applications along with cosmeceuticals. , – these delivery systems have enhanced effects in the delivery of phytobioactive compounds in oral therapy, which boosts the cosmeceutical sectors for the development of cosme- ceuticals with enhanced activity by topical application. however, synthetic compounds are extensively developed using this technique, and phytocompounds used for cos- meceuticals are limited. recently, resveratrol and curcumin were constructed using lipid core nanocapsules at nm with an increased retention of polyphenols in the skin and increased skin protection. this confirms that coencapsula- tion enhances the bioavailability compounds in the skin and promotes skin protection against physiological environments. this technology will be potentially useful in the near future of the cosmeceuticals sectors. similarly, an individual phyto- compound of resveratrol was constructed using lipid-derived nanocapsules at nm that enhanced skin protection with higher bioavailability of those bioactive compounds under uv radiation. chitosan hydrogels combine nanocapsules with the active compounds of capsaicinoids and enhance skin protection by the control release of those compounds. – the same research group studied the effects of capsaicinoids in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress phyto-based nanocosmeceuticals for skin therapy in nanocapsules and found greater skin care with sustained release. these studies confirm that phyto-derived bioactive compounds can be used for the construction of nanocapsules to apply in cosmeceutical sectors and beauty therapies. nanophytosomes phytosomes are another novel technology, particularly for plant polyphenolics, which enhance bioavailability of phyto- bioactive compounds to the skin and in other therapeutic applications – for skin beauty and health care. the greater advantage of these techniques involves chemical bonding between the polyphenolics and the lipid bilayer and thereby enhances the physical stability of bioactive compounds, which prolong the compound’s effectiveness. , phytosomes are extensively used in cosmeceutical sectors for their beauty and therapeutic applications with the phyto-derived crude extracts or with the individual bioactive compounds. , recently, extracts from the citrus auranticum and glycyrrhiza glabra were used for the construction of phytosomes and for the skin aging studies. the researchers confirmed that phytosomes enhance the bioavailability of those compounds in cream and thereby protect skin from aging. further, nanosizing of those phytosomes increases the bioavailability of those compounds for beauty and health care applications. , gold nanoparticle-bound phytosomes containing phytoextracts rich in quercetin were constructed and had enhanced querce- tin efficiency at a particle size of nm. similarly, rutin- based phytosomes were developed with enhanced compound bioavailability and antioxidant activity. nanoliposomes liposomes are effective in carrying phytobioactive compounds in cosmeceuticals. products containing liposomes increase skin protection and beauty qualities. , – generally, nano- liposomes are spherical, have a uni- or multilamellar struc- tures, and are a few nanometers in size. liposomes have high efficiency in phyto-based compounds delivery to the dermal layer. nanoliposomes are used in cosmeceutical products such as antiaging cream, sun block cream, hair cream, and skin moisturizer, which contain synthetic as well as phytobioactive compounds. , – the major advantages of nanoliposomes are their unique size, they can encapsulate hydrophilic and hydrophobic bioactive compounds, uv absorbing lipids can protect the skin and the bioactive compounds without further degradation. , figure shows the possible nanoliposome mechanism in reducing skin wrinkles. among nanoliposomes that contain phytobioactive compounds, curcumin was studied with enhanced stability and prolonged activity of transdermal application. recently, curcumin-loaded nm nanoli- posomes were constructed and showed skin protection. figure nanoliposome-based delivery of antioxidants for skin wrinkles in antiaging treatment. in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress ganesan and choi the same research group focused on nm nanoliposome development with long circulating nanoliposomes for skin care and disease treatment. the combination of curcumin with hyaluronic acid enhances the bioavailability of curcumin in the skin and body, which leads to many novel nanoap- proaches for the skin-based nanotherapautics and beauty. even though several phytocompound-encapsulated liposome technologies are used in cosmeceuticals and therapy, the nano- size of liposomes is still in the budding stages with the active phyto-derived compounds. phytocompound-encapsulated liposomes will be an innovative technology in the near future for application in therapy-based beauty. nanoniosomes niosomes are extensively used in cosmeceutical sectors since it has multiple advantages over liposomes such as higher stability, enhanced skin penetration, low toxicity, and higher protection of the bioactive compounds. – niosome sizes vary from nanometer to micrometer, the lower the size greater the efficiency. nanoniosomes are smaller, unilamellar structures in the size range of – nm. – niosomes are extensively used to deliver antioxidants such as ascorbic acid, resveratrol, and ellagic acid through skin and are used orally to treat diseases. , – even though commercially many cosmeceutical creams and lotions contain niosomes with synthetic compounds, phyto-derived bioactive compound usage is a new sector in the development of nanoniosomes. recently, tavano et al produced a slightly larger niosome in the size range of – nm containing phyto-derived anti- oxidants such as resveratrol, alpha-tocopherol, and curcumin. this product showed enhanced antioxidant activity to the skin with increased skin permeation activity for cosmeceuti- cal applications. this study confirmed that phyto-derived compounds can be effectively used in noisome formulation for cosmeceutical applications without change in bioactivity and enhanced skin protection. however, the size is a big factor, and reduction to nanosize with alteration in produc- tion methods may enhance their activity with a broad range of applications in cosmeceutical sectors. recently, individual phytocompounds, such as curcumin, were developed using nanoniosome methods in the size range of nm and showed enhanced skin protective activity. – from the earlier studies, phytocompound-containing nanoniosomes may be useful for both cosmeceuticals and pharmaceutical sectors. nanoethosomes, glycerosomes, and hyalurosomes ethosome, glycerosomes, and hyalurosomes are modi- fied liposomes, named based on their compounds used in the phospholipids, such as ethanol, glycerol, or sodium hyaluronate. they are modified for the enhanced delivery of the active ingredients to the skin and exclusively used in cosmeceutical sectors for their therapy and beauty treatments. , further, nanosizing of vesicles with incorpo- ration of phytocompounds showed enhanced protective and beauty activity. – recently, quercetin glycerosomes were developed in the size range of – nm with a unilamellar structure and showed enhanced skin protective activity. this may be used in the future for the production of antioxi- dant skin cream. ethosomes nanovesicles in the size range of nm were prepared with polyphenolic extracts of fraxinus angustifolia leaf and bark and showed enhanced wound heal- ing and skin protection activity. similar to the ethosomes, nanosized hyalurosomes of liquorice extract were prepared in the size range of nm and enhanced skin beauty. the same research group also developed curcumin-based nanohyalurosomes with a minimal particle size of nm and showed enhanced skin beauty-based therapy. from these studies, extracts can be used to develop nanovesicles, which could be efficiently used in the cosmeceutical sector, and it will give a broader scope of research and development for cosmeceutical products with multiple efficiencies. fullerene fullerene is yet another novel technology made of carbon atoms of nm size, consisting of even numbers known as c , which is used in the cosmeceutical sectors to carry phy- tocompounds. fullerene itself acts as an antioxidant and pre- vents premature skin aging. – fullerene delivers vitamins to effectively enhance the skin. recently, some researchers developed a fullerene nanocapsule with ascorbic acid and vitamin e. it showed enhanced skin protective activity against premature aging by its antioxidant activities. , further, skin protection was also enhanced by the fullerenes with some modifications. – fullerene-based photodynamic therapy was used for skin-based disease treatment with the bioactive compounds, such as curcumin. , however, further study on the application of various phyto-derived bioactive com- pounds with fullerenes in cosmeceutical-based skin therapy has yet to be carried out. this will give way for the develop- ment of the new cosmeceutical products with better protective activity by the carrier and bioactive compounds. carbon nanotubes carbon nanotubes are a novel technology currently used in the cosmeceutical sectors particularly for the skin care. similar to fullerene, carbon nanotubes alone act as an antioxidant at nm in size. , in addition to their uses in in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress phyto-based nanocosmeceuticals for skin therapy cosmeceutical sectors, they are effective in delivery systems for phytocompounds in biomedical applications. , , recently, curcumin was conjugated to a single wall carbon nanotube for the effective delivery. the role of hyaluronic acids in the delivery of drugs using carbon nanotubes was reviewed recently, and further clinical trials are needed to assess their biosafety. however, a study on the application of carbon nanotubes with phytocompounds in skin care and cosmeceuticals is yet to be done. phytoconstituents in nanosize cosmeceuticals and skin therapy nanosize phytoconstituents are gaining popularity among the active ingredients in the cosmeceuticals, as they enhance beauty and have therapeutic roles in diseases such as antiaging, uv protection, and prevention of skin-related diseases. , – increased skin protective activity of bio- active compounds is related to polyphenol content along with their reduced size. compounds vary from macro to nano and with skin penetration using different delivery techniques. , – recently, resveratrol encapsulated in the solid lipid nanoparticle showed enhanced skin uptake with increased protection and antioxidant activity. solid lipid nanoparticles were compared nanostructured lipid carrier systems and found similar efficiencies with increased reten- tion in the skin. nanodelivery technologies also enhance the compound bioavailability not only to the skin but also to the brain to treat disorders such as parkinson’s disease. further modification of bioactive compounds along with the nanodelivery technologies can enhance skin bioavailability to increase protection. similarly, quercetin encapsulated into a solid lipid nanoparticle system showed increased skin reten- tion of quercetin with greater antioxidant activity. , , genistein-loaded nanoemulsions were incorporated into hydrogels in the size range of nm and enhanced delivery of the bioactive compound to the skin for a beauty-based therapy. in addition, coencapsulation of resveratrol and cur- cumin with lipid core nanocapsules increased delivery of the resveratrol to the skin. further, several other phytobioactive compounds were efficiently encapsulated into various nano- delivery systems to enhance beauty and therapy applications. specific compounds, their skin protecting activity, and beauty applications are discussed in the following sections. some of the nanophytobioactive compounds and its role in beauty and skin therapy are listed in table . nano aloe vera aloe vera consists of several active constituents such as proteins, minerals, carbohydrates, and vitamins from the inner portions of the leaf, which are widely used in the skin care and the medicine. – aloe gel greatly enhances mois- turizing activity and antiaging by enhancing the synthesis of collagen and elastin fibers. in addition, it also helps in the wound healing. – the higher moisture, bioactive compound, and mineral content of aloe gel enhance the moisturizing effects and skin protection. therefore, aloe is often used in cosmetic products such as creams, lotions, and gels. , , however, for their enhanced bioactivity of the aloe compounds, nanodelivery techniques are recently used in the cosmeceutical sections. further, the use of nanosize a. vera in the preparation of cosmeceutical products is now in early stages. few nanotechniques enhanced skin care activities. a. vera gel extract liposomes were constructed, with the particle size of nm, that enhanced skin collagen synthesis and growth of skin cell lines, which confirm that it may be used to enhance skin care products. similarly, some researchers patented nanoemulsion technology varying the nanosize containing a. vera extract. the resulting prod- uct caused skin rejuvenation and had antiwrinkle activity. in addition, coencapsulation of a. vera with curcumin enhances phytocompound delivery to the skin and protects antioxidant activity. from the earlier studies, nanosiz- ing bioactive compounds from a. vera enhances beauty applications. further development of various nanodelivery techniques is a good research opportunity. nanocurcumin curcumin is the active compound in turmeric, which is native to india and other asian countries. turmeric is widely used in cooking, medicine, beauty, and health products. – turmeric as a crude extract or tuber powder normally used for skin care among south indian women in their daily rou- tine owing to its multibeneficial activities such as antiaging, moisture retention, antioxidant activity, and natural beauty products with yellow pigments. – although turmeric has multiple beneficial activities, its bright yellow color and instability under certain environmental conditions make researchers look for alternative delivery technologies for skin care and beauty applications. nanodelivery techniques such as solid lipid nanocarriers, nanoliposomes, nanonio- somes, and nanoemulsions solve most of their difficulties with turmeric and enhance the bioavailability of its polyphe- nolic compounds in cosmeceutical product. , , curcumin nanotransfersomes, nanoethosomes, and nanoliposomes were prepared and studied for the skin hydration and uv protec- tion activity. three nanodelivery technologies enhanced the delivery of curcumin to the skin with greater hydration and uv protective in cream containing the nanoformulations. in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress ganesan and choi greater efficiency among the nanodelivery techniques was observed in the order of nanotransfersomes having the most efficiency, nanoethosomes and nanoliposomes having the least. they also varied in size from nm to nm. in another study, curcumin nanoethosomes were prepared with particle sizes of nm and enhanced antiwrinkle properties. further, skin permeation of the curcumin-loaded nanoliposome with particle sizes of – nm showed higher skin protection. similarly, nanohyaluronosomes with particle sizes of – nm enhanced curcumin bioavail- ability to the skin and will potentially be used for beauty- based therapies in near future. similarly, curcumin-loaded niosomes were prepared with enhanced bioavailability in the skin. in addition to the individual compounds, coad- ministration of curcumin with resveratrol in the lipid core nanocapsules increased delivery of the phytocompounds to the skin with better antioxidant potential and skin care. likewise, codelivery of curcumin with resveratrol in the nanosized niosomal formulations enhanced skin beauty with increased antioxidant activity. nanovitamin e vitamin e is heat stable fat soluble compound most com- monly used in cosmeceuticals for skin protection properties such as antiwrinkle, enhanced skin moisturizing, and preven- tion of skin disease. since most cosmeceutical products contain the precursor of active tocopherol and its cleavage products in the skin is minimal, which leads to a decrease in skin protection. even though vitamin e is naturally present in human skin, most of it is not active due to prolonged solar irradiation. nanodelivery techniques solve issues with suf- ficient delivery along with prolonged and sustained release of vitamin e associated with enhanced beauty. vitamin e nanoemulsion was prepared using nanoemulsion techniques and enhanced bioavailability of the vitamin compared to microsized emulsions. vitamin e was also prepared using table nanosized phytocompounds used in cosmeceuticals s no phytocompounds nanodelivery methods size (nm) applications references rice bran oil nanoemulsion moisturizers bernardi et al antiaging skin care skin care rice bran and raspberry seed oil lipid nanocarriers sunscreens niculae et al lavender extracts polymeric poly(lactic-co-glycolic) acid (plga) nanoparticle – antiaging pereira et al antioxidant rosemary extracts solid lipid nanocarriers antioxidant (skin) lacatusu et al nanostructured lipid carriers antioxidant aloe vera extract nanoliposome skin care takahashi et al saflower extracts nanostructured lipid carriers hair care kumar et al lutein nanostructured lipid carriers and nanoemulsion – skin care mitri et al quercetin nanostructured lipid carriers skin care guo et al ganoderma triterpenoids nanostructured lipid carriers – gel skin enhancement shen et al hinokitiol poly(epsilon-caprolacton) nanocapsules hair care hwang and kim hinokital bilayer vesicles hair growth yang et al curcumin nanoencapsulation and skin care suwannateep et al tocopherol nanostructured lipid carriers (nlcs) and nanoemulsion (ne) and skin care abla and banga resveratrol solid lipid nanoparticles versus nanostructured lipid carriers . and . skin care gokce et al resveratrol niosomes skin care pando et al resveratrol and curcumin lipid care nanocapsules – skin care friedrich et al resveratrol, alpha-tocopherol, and curcumin niosomes – skin care tavano et al d-limonene nanoemulsions skin care lu et al aqueous propolis and lycopene nanoemulsions na skin care butnariu and giuchici lycopene transfersomes skin care ascenso et al ethosomes skin care ascenso et al abbreviation: na, not available. in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress phyto-based nanocosmeceuticals for skin therapy solid lipid nanoparticle delivery systems with size equivalent to nm and enhanced skin protection activity. further, solid lipid nanoparticle vitamin e preparation enhanced vitamin e delivery for cosmeceutical-based skin therapy. – teo et al reported that vitamin e-enriched palm oil nano- emulsions with particle sizes of nm enhanced product stability and may be useful for their novel nanosized cos- meceuticals. in near future, vitamin e will be delivered with suitable nanodelivery technologies in therapy-based cosme- ceuticals for enhanced activity, stability, and beauty care. nanovitamin c vitamin c is a vitamin abundant in plants and has multiple roles in the beauty and health care, involving collagen synthesis. , vitamin c readily undergoes degradation when exposed to harsh environments and uv radiation. a continuous supply of vitamin c compounds enhances the skin’s beauty. nanodelivery techniques help sustain vitamin c supplementation without changes in its biological activity after applying to the skin. recently, several nanotech- nological approaches have been published using vitamin c for skin health and beauty, such as solid lipid nanoparticles and nanostructured lipid carriers. vitamin c-encapsulated solid lipid nanoparticle was prepared with a particle size of – nm. solid lipid nanoparticle enhanced the carrier of the vitamin against apoptotic effects. similarly, nanolipo- somes were constructed using vitamin c that enhanced skin permeation activities with different particle sizes, ranging from nm to nm. in addition, vitamin c nanolipo- somes had enhanced stability and higher antioxidant activity compared to ordinary liposomes after days of storage. in another study, a vitamin c and gold-loaded nanofiber mask were prepared for the effective delivery of vitamins to the face. the liposomal preparation delivery of vitamins through mask enhanced facial beauty. therefore, vitamin c can be delivered to the skin using nanodelivery technologies for enhanced skin beauty-based therapies. nanoresveratrol resveratrol is another polyphenolic compound with multiple beneficial roles in quenching free radicals and protecting skin against harmful environmental conditions. polyphenolic compounds inhibit oxidative mechanisms and uv-induced radiation. they are widely used in functional foods for skin care and health. , – in comparison to other antioxidants, resveratrol shows higher efficiency of skin protection against uv-b radiation. , however, resveratrol stability and beauty effects are limited due to compound degradation under harsh environmental conditions. to overcome this, nanodelivery techniques such as solid lipid nanoparticles, nanoemulsions, and transfersomes showed enhanced res- veratrol stability and delivery to the skin. , , recently, microemulsions were constructed using resveratrol with particle sizes of – nm that enhanced resveratrol bioavail- ability to the skin to protect against uv radiation. recently, three different nanodelivery techniques, such as solid lipid nanocarrier, nanostructured lipid carrier, and nanoemulsions, were studied for resveratrol delivery efficiency to the skin. among them, the solid lipid nanocarrier preparation has the most enhanced resveratrol delivery to the skin. analyzing resveratrol nanodelivery studies, we conclude resveratrol may be highly protective through nanodelivery techniques and may be used in the preparation of natural nanocosme- ceutical products to enhance beauty. nanoquercetin quercetin is another phytoactive flavonoid compound having efficiency in multiple aspects such as skin care and beauty through antioxidant activities; thereby, it enhances skin beauty and personal care. – in comparison to other fla- vonoids, quercetin showed higher skin protecting efficiency and enhanced beauty due to its abundance of oh groups. this leads many researchers to analyze the multiple efficiencies of quercetin in cosmetics. however, the major drawback of quercetin applications is its stability and penetrating effi- ciency, which is solved by nanodelivery techniques. solid lipid nanoparticle and nanostructured lipid carrier nanode- livery systems were compared for the effective delivery of the quercetin to the skin. the nanostructured lipid carrier showed higher quercetin retention in the skin membrane with a particle size of ~ nm. the same research group also suggests that quercetin in the solid lipid nanoparticle prepa- ration has increased skin protection against uv radiation of human skin. nanoglycerosomes were also prepared with particle sizes between nm and nm that enhanced skin delivery of quercetin along with its photoprotective effects against oxidative damage. similarly, quercetin-rich nano- emulsions and a. satureioides nanoemulsions were prepared with nanoparticles ranging from nm to nm. this preparation had higher skin retention of the phytocompounds with increased skin protecting activity. in another study, quercetin-loaded nanocapsules were constructed with a par- ticle size of nm for sustained delivery of quercetin to the skin to increase antioxidant activity. from these studies, we conclude that quercetin may be used in the preparation of various nanosized cosmeceuticals products with increased in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress ganesan and choi stability, prolonged beautifying effects, and without harmful side effects. nanogreen tea natural green tea extract is rich source of bioactive com- pounds, such as catechin, epigallectocatechin, epicatechin, and epigallecto- -catechin, which are powerful antioxidants widely used in skin care and beauty treatments. – the individual potential of these compounds also varies in usage for development of cosmeceutical products. green tea com- ponents have multiple skin care roles such as antiaging and prevention of uv-induced photoaging. , – the bioactive compounds readily undergo functional group loss during the exposure to environmental conditions and decrease the stability of the compounds, which limits the application of these compounds in cosmeceutical products. nanodelivery techniques enhance the bioavailability of these compounds in cosmeceutical products, thereby enhancing their usage in the novel development of green tea-based cosmeceuticals. recently, montenegro listed group of phytocompounds usage in commercial products. among them, green tea catechins were used in antiaging cream preparation with fullerene as the delivery agent. fang et al also prepared green tea catechin liposomes with nanoparticle sizes of – nm that enhanced antioxidant activity in the skin. in another study, green tea liposomes, with a reduced particle size of ~ nm, enhanced green tea catechins by ethanol incorporation into the liposomes for enhanced transdermal delivery. similarly, green tea polyphenol nanoliposomes were developed using milk fat globule membranes and soy lipids to enhance antioxidant activity in the cell model. these studies suggest that green tea polyphenols can be sufficiently nanodelivered to various skin care products for their sustained beautifying effects. nanogenistein genistein is one of the major isoflavones found in many cereal plants and has skin protecting activities, including antioxidant, collagen synthesis, uv protection, and antiag- ing benefits. – even though genistein has skin protecting activity and enhances beauty, its sustained effect is still limited due to lower stability in cosmeceutical products. in order to enhance stability and prolong activity, nanosized delivery technologies have greater impact in cosmeceutical sectors. genistein-loaded nanoemulsions were prepared with nm sized nanoparticles and enhanced delivery of isoflavones to the skin with higher skin protecting activity. in another study, nanosized liposome-encapsulated genistein in nanoparticles the size of nm was tested on rat skin, with or without hair. in addition to the nanosized liposomes, the hairs on the skin also affect the delivery of the genistein compound to the skin. nanolycopene lycopene is another natural phytobioactive compound with multiple applications in skin care, including antiaging and antioxidant activity. – owing to its lipophilic nature and decreased delivery to the skin, lycopene is of limited usage in skin care products. in addition to its lipophilic nature, lycopene readily undergoes degradation during light and air exposure, which further limits its usage in cosmeceu- ticals. however, nanosizing lycopene solves most of these problems and enhances its bioavailability. , , recently, lycopene ethosomes and transfersomes were constructed in the nanosize of nm and nm, respectively, which enhance the bioavailability lycopene to the skin with poten- tial antioxidant activity. further, it enhances the penetration of lycopene to the inner cell and nucleus, which could be useful in skin protection and care. research focusing on nanodelivery in cosmeceutical products containing lycopene is still limited. nanotoxicity the major concern of using nanocosmeceuticals is toxicity owing to the small size, allowing the particles to cross the membrane easily and interact with other proteins and cells. this may lead to the other effects by their subsequent meta- bolic products. before applying the products, extensive clinical screening must be done, even though many reports suggest that polymers in cosmeceuticals have no deleterious effects. further, natural products have no side effects. exten- sive use of these compounds may also lead to side effects. further clinical support is needed before nanotechnology proceeds to commercialization and product development. conclusion the greater demand of the nanosized phyto-based bioactive compound usage in the development of nanocosmeceuticals for skincare-based therapy such as moisturizing, sun block, anti-aging, whitening effects along with skin health leads many researchers in search of novel nanocosemecutical- based therapy. nanosized cosmeceuticals with phyto-based bioactive compounds retain higher amounts of bioactive compounds in the skin, are more stable, and enhance skin appeal with prolong time. nanosized compounds range in size. increasing the nanosize limits the penetration ability of in te rn a tio n a l j o u rn a l o f n a n o m e d ic in e d o w n lo a d e d f ro m h tt p s: // w w w .d o ve p re ss .c o m / b y . . . o n -a p r- f o r p e rs o n a l u se o n ly . powered by tcpdf (www.tcpdf.org) / www.dovepress.com www.dovepress.com www.dovepress.com international journal of nanomedicine : submit your manuscript | www.dovepress.com dovepress dovepress phyto-based nanocosmeceuticals for skin therapy bioactive compounds to the skin, which limits beautifying and therapeutic activities. the solubility types and the cos- meceutical application of phyto-based bioactive compounds determine the delivery technology for nanocosmeceutical development. further research of their mechanisms is nec- essary to target site release from the delivery agents. this further boosts nanosized phytobioactive compound-based cosmeceutical research and skin health. acknowledgment this work was supported by the konkuk university in . disclosure the authors report no conflicts of 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implications of convergent evolution george mcghee: convergent evolution: limited forms most beautiful mit press, , hardcover, pp russell powell • carlos mariscal received: january / accepted: january / published online: february � springer science+business media dordrecht interest in the evolutionary theoretical implications of convergent evolution has surged over the last decade, in part due to accessible monographs (such as conway morris ) that have drawn attention to this important and under-investigated evolutionary phenomenon. just how ubiquitous is convergent evolution in the history of life, and what does the frequency of convergence tell us about the constraints on macroevolution as it has unfolded on earth and as it might do in other nooks and crannies of the habitable universe? convergent evolution: limited forms most beautiful is an exceedingly well- researched, lucidly written, and wonderfully synthetic review of convergent evolution research, making a strong case for the ubiquity of convergent evolution at all levels of the biological hierarchy. mcghee has compiled an impressive evidence base to be mined by future researchers, and the book is brimming with fascinating and underappreciated examples, some of which are of great evolutionary significance. unlike existing monographs on the topic, convergent evolution is illustrated with clear, accessible figures and makes extensive use of cladograms that underscore the phylogenetic distance bridged by convergent events. it is now arguably the definitive empirical source for any biologist or non-specialist interested in the phenomenon of convergent evolution. however, like similar works before it, mcghee’s exposition is somewhat less effective on the theoretical and philosophical fronts. before canvassing our major criticisms of the book, we will provide a brief summary of each chapter. r. powell (&) department of philosophy, center for the philosophy and history of science, boston university, boston, ma, usa e-mail: powell@bu.edu c. mariscal department of philosophy, center for philosophy of biology, duke university, durham, nc, usa e-mail: cm @duke.edu acta biotheor ( ) : – doi . /s - - - in the first chapter, mcghee introduces the phenomenon of convergent evolution and offers a terse treatment of definitional problems surrounding the concept of homoplasy. this crucial introductory chapter contains far less conceptual and methodological meat than one might expect of a work in theoretical biology. for instance, it fails to even gesture at problems confronting modern cladistics and phylogenetic inference, the contested nature of the homology concept, and philosophical debates over how we might distinguish between different types of convergent evolution. like conway morris before him, mcghee treats parallel evolution, both in this chapter and throughout the book, as ‘‘simply a type of convergent evolution’’ (p. ), without considering its deeper theoretical significance. on mcghee’s proffered definition, ‘‘parallelism’’ refers to homoplasy that is produced from the same ancestral character or through cooptation of the same genetic-developmental resources, such as deep homologs. there are a host of empirical, methodological and conceptual problems that confront attempts to delineate parallelism in these ways, which mcghee fails to consider; these range from conceptions of sameness, to the level-relative nature of homology judgments, to the lack of total homology in the gene networks that are developmentally responsible for parallelism in closely related groups (for discussions of these and other problems, see e.g., currie ; pearce ; powell ; ramsey and peterson ; arendt and reznick ). furthermore, by characterizing both parallel and convergent events as independently derived outcomes, mcghee glosses over the theoretical importance of this distinction and its implications for our understanding of constraints on the shape of complex multicellular life (more on this below). chapter is a tour de force of convergent evolution in animals, including (inter alia) swimming, flying, walking, burrowing and other locomotory morphologies, sensory modalities, teeth, beaks and claws, poison injection systems, digestive capabilities, defensive structures, reproductive strategies, and so on. this is easily the strongest chapter in the book, making a powerful case for the ubiquity and importance of convergence in animal evolution. importantly, here and throughout the book, mcghee also considers intriguing instances of non-convergence, such as the lack of snake-like morphologies in mammals and the absence of mole-like excavator morphologies in reptiles. the chapter also takes developmental constraints seriously (though not seriously enough—see discussion below), explaining why ‘centaur-like’ forms (possessing four legs and two arms) cannot evolve within the confines of the four-limbed vertebrate body plan, but have evolved, repeatedly, in insects (namely, with respect to iterated ‘mantis’ forms). in contrast, mcghee shows that external physical constraints may explain why, for example, no predator has ever evolved eyes that can resolve the infrared range of the electromagnetic spectrum despite the obvious fitness advantages such an adaptation would confer. chapter reviews convergences within the plant clade. featuring the exceptional work of the biologist karl niklas and others, mcghee argues that convergence along multiple parameters on tree and leaf morphologies, water transport and root systems, and other structures has occurred repeatedly due to functional constraints imposed by the physical laws. mcghee argues, convincingly, that in both animals r. powell, c. mariscal and plants, convergent reproductive strategies dwarf quintessential cases of morphological convergence—as is the case, for example, with viviparity in animals, and heterospory, seed and seed-dispersal systems in plants. it is important to note that many of the key convergences in plants hinge on the existence of animal pollinators and animal seed dispersal mechanisms. plant-animal coevolutionary interaction appears to add layers of contingency to the evolution of certain iterated plant morphologies, as well as to the evolution of particular ecotypes (discussed in the next chapter), which the author fails to consider. chapter sets out in search of a ‘‘periodic table of niches,’’ focusing on the iterated evolution of ecotypes (such as insectivore, nectarivore, carnivore, omnivore, herbivore, chase predator, ambush predator, etc.), and ecomorphs (such as ‘vulture’, ‘lion’, ‘ungulate’ and ‘mole’). mcghee takes convergence in ecomorphology, such as the strikingly similar faunas that evolved in parallel between marsupial and placental mammals, as evidence that ‘‘these [specialized] ecological roles exist in the absence of either placental or marsupial mammals and, since the placentals were not present in australia, the marsupials independently discovered them in their own separate evolution’’ (p. ). this conclusion is problematic because it fails to consider how contingent mammalian (and more broadly tetrapodian) body plans constrain and underwrite iterated ecological evolution. the discussion of pre-existing niches would also have benefited from connecting up with the wider theoretical literature on organism-niche codetermi- nation, in particular with richard lewontin’s well-known critique of so-called ‘lock-and-key’ models of ecological evolution. these quibbles aside, perhaps the most significant problem with this chapter—one that is symptomatic of an overarching impediment to the convergence project—is that it lumps plausible candidates for universal niches (such as broadly defined ecotypes) together with arguably more contingent iterated outcomes, such as ecomorphs that hinge on the tetrapodian body plan. for instance, the generalization ‘‘there will never evolve a sessile herbivore for sessile plants’’ seems to be far stronger (i.e., more widely applicable) than the claim ‘‘there will evolve a lion ecomorph,’’ due to the sheer number contingencies that arguably underlie the evolution of mammalian and more broadly tetrapodian developmental architecture. we discuss this lumping problem in greater detail below. chapter offers a preliminary examination of convergent evolution at the lowest scales in the biological hierarchy, from nucleic and amino acids to proteins. among the most intriguing examples are the convergent evolutions of identical nucleotide substitutions producing similar sensitivities to light, of antifreeze protein molecules in cold-water fishes, and of enzymes that catalyze the first step in sugar metabolism. homoplasy research is typically focused on the macromorphology of animals and plants, and thus mcghee’s attention to convergence at the microscopic scale is much welcome. nevertheless, his overarching analysis of convergence remains macromorphocentric, considering only a handful of examples of convergence in prokaryotes and never even mentioning archea. thus, convergent evolution among single-celled organisms remains an important and under-investigated area that is ripe for future research. george mcghee: convergent evolution chapter is, in our opinion, the weakest chapter in the book. it is sold as a review of convergent minds when in actuality it details convergence in behaviors. prominent examples in the chapter include the ‘‘farming phenotype’’ arrived at by both ants (first) and humans (more recently), and ‘‘tool use’’ across vertebrate and even in some insect groups. these behavioral traits are clearly not underpinned by similar mental/cognitive mechanisms in the groups that have converged on them. it is well established in ethology that similar behaviors can be produced by fundamentally different mental activities and cognitive processes, a point overlooked by mcghee when he argues ‘‘animals with radically different brains have evolved the same architectural behaviors. those analogous behaviors thus reflect analogous mental activities and cognitive strategies taking place in independent lineages, which is convergent mental evolution’’ (p. ). mcghee thus makes the fallacious leap from ‘‘same behavior’’ to ‘‘same underlying mental/ cognitive processes.’’ yet few would be sympathetic, for example, to mcghee’s claim (p. ) that the ‘‘agricultural minds’’ of ants and humans are the subject of cognitive convergence. the same is true for the mental mechanisms underlying herding behavior and pack hunting among various vertebrate clades. nor is it clear that the loosely analogous phenotypes referred to in this chapter, such as ‘‘farming’’, ‘‘tool use’’, and ‘‘architectural behavior,’’ are genuine natural kinds or even sufficiently similar traits to be properly classified as cases of convergence (though the impressive suite of independently derived agricultural features may suggest that this trait can be satisfactorily delineated). although there is some discussion of convergent metacognition—among the few genuinely ‘mental’ elements of the chapter—mcghee curiously omits recent work on cephalopod cognition, which is without question the most robust example of sophisticated cognitive convergence that we know of, given that mollusks and vertebrates share an essentially brainless common ancestor in the base of the cambrian. it is not until chapter that the heavy philosophical lifting begins. here, mcghee provides a theoretical framework and a series of useful figures for conceiving of the realm of the biologically possible, and for illustrating the interaction between internal (developmental) and external (functional) constraints that shape morpho- space occupation (see fig. ). this chapter would have benefited, however, from closer contact with the astrobiological literature on possible life (c.f. schulze- makuch and irwin ), as well as the philosophical literature on constraints in biology (c.f. amundson ; sansom ). we finally come to the ‘philosophical’ implications of convergent evolution in the eponymous final chapter of the book. disappointingly, it fails to wade into any major conceptual or methodological problems in the philosophy of biology that pertain to the present project. instead, it proceeds to consider the implications of the radical evolutionary contingency thesis (and its antithesis) for our ability to find meaning in the universe and for the plausibility of theism. frustratingly, mcghee presents a buffet of views on these matters without ever taking a clear stand or adjudicating their respective plausibilities. he does, however, in concluding the book, inveigh against what we believe to be an uncharitable caricature of the opposing gouldian view of life, which we discuss in more detail below. r. powell, c. mariscal this brings us to overarching concerns with the book. convergent evolution’s greatest asset—its massive inventory of exemplar convergent events in the history of life—is also its greatest flaw. like other recent attempts to establish the empirical and theoretical importance of homoplasy, mcghee’s monograph is guilty of ‘lumping’ disparate convergent phenomenon into a single basket and proclaiming the ubiquity of the phenomenon. in effect, it treats all instances of homoplasy as if they are of comparable theoretical import, nomic necessity, and counterfactual robustness. yet some proffered examples of convergence are the basis of far stronger generalizations than others, and mcghee offers no principled way of determining the relative significance of convergent outcomes. for instance, he lists nine examples of plants that have evolved vessels to transport water, and over twice as many examples of convergence in flowers that facilitate beetle pollination—but surely we would expect vessels to evolve earlier, more frequently, and more consistently in any given evolutionary system than features that are contingent on beetle pollination. in this respect at least, the whole is less than the sum of its parts, permitting uncharitable opponents to seize on the weakest cases in arguing against the law-like implications of convergence. in our own future work on this topic, we aim to develop a typology of convergence that breaks down the heterogeneous reference class of convergent events in accordance with the robustness of the generalizations they can plausibly support. mcghee’s review will no doubt serve as a critical empirical resource for this conceptual project. a second major problem with the book is that it fails to seriously engage with, and systematically mischaracterizes, stephen jay gould’s ( ) ‘‘radical contin- gency thesis.’’ gould’s controversial, thought-provoking thesis is arguably the major motivation for recent work on convergent evolution, and yet it is not introduced until the very end of the book and then only briefly discussed (p. ). and even there, it is considered only in relation to finding meaning in the universe. like others before him, mcghee touts the ubiquity of convergent evolution as a rebuke of gould’s claim that the overarching shape of life is deeply historically contingent. the problem, however, is that mcghee’s analysis never actually comes into contact with the core claims of gould’s thesis. it would have been helpful if mcghee had used the diagram from chapter to contrast his view of life with that of fig. adapted from figure . (p. ). f: is the set of biological forms that are non- functional and cannot be developed by life on earth. f: is the set of biological forms that are functional and can be developed by life on earth. f: is the set of biological forms that are nonfunctional but could be developed by life on earth. finally, f: is the set of biological forms that are functional but cannot be developed by life on earth george mcghee: convergent evolution gould, perhaps by drawing smaller boundaries around the space of forms that are functional, developmentally possible, and actual (see fig. ). instead, mcghee refutes a series of claims that gould did not hold, and with which gould would be unlikely to disagree. for instance, mcghee arrives at the following two main conclusions (p. ). ‘‘first, the view that the evolutionary process is nonrepeating (nonergotic) is demonstrably false.’’ nobody, and certainly not gould, would hold such a blatantly false view, and thus mcghee dismantles a straw man in a way that obscures the genuine debate—which is really about the extent to which internal developmental constraints (including the broad parameters of animal body plans) are responsible for much or even most of the morphological reiteration. contrary to mcghee, there is room within the gouldian view of life, with its emphasis on internally constrained parallelism, for a great deal of reiteration and predictability (for a discussion, see powell ). second, the view that evolution is entirely historically contingent, and thus unpredictable (and nonrepeating), is demonstrably false.’’ let us set aside the problematic slide between epistemic issues (e.g., predictability) and metaphys- ical ones (e.g., the robustness of macroevolutionary pattern across changes in initial conditions). the trouble with this second conclusion is that once again, it is addressed to a straw man. occasional rhetorical flourish aside, neither gould nor any other contingency theorist could possibly hold that all of evolution is historically contingent. the convergence/contingency debate is clearly a relative significance dispute, and it should be characterized as such. in addition, we must be clear about two things here. the first relates to the way in which the concept of repeatability is being used in these disputes. precisely what degree of repeatability are we contemplating? mcghee is right that convergent evolution is often indicative of functional constraint. but the key point of contention between convergence proponents and contingency proponents is whether functional constraints transcend the entrenched development of any particular lineage. some instances of convergence, especially interphyletic and interkingdom convergence, do seem to contradict the gouldian narrative, while other instances of homoplasy do not (and could even be seen to bolster the gouldian view). what we need to develop, therefore, is a systematic way of distinguishing between these sorts of fig. in this modified version of fig. , f: is introduced to represent stephen j. gould’s radical contingency thesis, which holds that the actualized set of biological forms are but a small fraction of the set of functional, earth-possible morphologies r. powell, c. mariscal cases. second, we must be clear about the explanandum. if we are asking whether there is a high probability that teeth or the fusiform shape or the cambered wing foil would evolve in any given replay of complex multicellular life, then perhaps the amassed evidence of convergence points to an affirmative answer. if we are asking, instead, whether there is a high probability that dolphinoids would evolve in any given replay of complex multicellular life, then the amassed data on convergence is far weaker. since we only see dolphinoid convergence within the vertebrate body plan, this tells us little about the robustness of such outcomes across the whole of complex multicellular life on earth or as it might evolve on earth-like worlds. so gould’s claims about the contingent survival and developmental entrenchment of a ‘fortunate’ subset of actual (and possible) cambrian body plans are never directly addressed in the book. a final regrettable aspect of the book is that it fails to connect up with virtually any literature in the philosophy of science, including a sophisticated body of work on biological laws, homology, phylogenetic inference, constraint, evolutionary progress, niche construction, fine-tuning arguments, and so on, all of which would have enriched the theoretical discussion. in sum, convergent evolution is a seminal piece of synthetic empirical work that belongs on every biologist’s shelf. it falls short, however, when it comes to addressing important philosophical dimensions of the convergent evolution debate. it is only by developing concepts and methods for carving up the vast set of iterated evolutionary events that mcghee and others have admirably compiled that we will understand the full bio-philosophical implications of convergent evolution. acknowledgments russell powell is grateful to the john templeton foundation for its financial support. references amundson r ( ) two concepts of constraint: adaptationism and the challenge from developmental biology. philos sci : – arendt j, reznick d ( ) convergence and parallelism reconsidered: what have we learned about the genetics of adaptation? trends ecol evol ( ): – conway morris s ( ) life’s solution: inevitable humans in a lonely universe. university press, cambridge currie a ( ) venomous dinosaurs and rear-fanged snakes: homology and homoplasy characterized. erkenntnis: netherlands gould sj ( ) wonderful life: the burgess shale and the nature of history. w.w. norton and co, new york pearce t ( ) convergence and parallelism in evolution: a neo-gouldian account. br j philos sci ( ): – powell r ( ) convergent evolution and the limits of natural selection. eur j philos sci ( ): – ramsey g, peterson as ( ) sameness in biology. philos sci ( ): – sansom r ( ) constraining the adaptationism debate. biol philos ( ): – schulze-makuch d, irwin ln ( ) cosmic biology: how life could evolve on other worlds. praxis george mcghee: convergent evolution there is grandeur in this view of life: the bio-philosophical implications of convergent evolution george mcghee: convergent evolution: limited forms most beautiful mit press, , hardcover, pp acknowledgments references available on cms information server cms cr- / the compact muon solenoid experiment mailing address: cms cern, ch- geneva , switzerland conference report september beauty production and identification at cms alexander schmidt on behalf of the cms collaboration abstract at the lhc, b-hadrons will be produced in a very high quantity at a yet unreached center-of-mass energy, enabling precision measurements to improve our understanding of the physics of b-quarks. the capability to measure the inclusive b-hadron production cross section is discussed on the basis of realistic detector simulations. effects which are limiting the accessible range of differential cross sections are outlined. the identification of b-jets is a crucial tool for a large number of topics, like top quark physics, and po- tential discoveries of the higgs boson and supersymmetry. the applied methods of identifying b-jets are addressed and a discussion of the expected performance in terms of efficiencies and misidentifi- cation probabilities under realistic conditions is given. approaches to measure these efficiencies with real data are also presented. presented at beach , / / ,columbia, sc,united states of america introduction b-hadrons are involved in a huge variety of physics studies at the lhc. this is not only true for the b-physics focused lhcb experiment but also for the general purpose experiments cms and atlas. the precise knowledge of the b production cross-section is of crucial importance for an understanding of backgrounds in many searches for physics beyond the standard model (bsm). this measurement also provides a good test of the theoretical qcd predictions that have recently been subject to many discussions. the b-quark production cross-section was first measured in by the ua experiment at cern [ ]. later measurements at the tevatron [ , , , , ] showed significant deviations from the theoretical predictions, even when running at ua energies [ ]. recent calculations [ ] with improved fragmentation schemes lead to a better agreement so that the differences are not alarming anymore. the kinematical range accessible by experiments has been quite limited so far and it will be significantly extended by the lhc experiments. studies for cms, based on monte carlo simulations, suggest that the differential bb production cross-section can be measured up to pt < . tev [ ]. this will be discussed in more detail in section . an important part of this analysis is the application of methods to identify hadronic jets stemming from b-quarks. processes with b-quarks in the final state need to be identified efficiently and inclusively for a wide range of other studies, for example in top quark and higgs physics. for instance, the standard model higgs boson decays preferably into b-quarks with a branching ratio larger than % for low masses (mh < gev). recent studies [ ] showed that the discovery of the h → bb decay is extremely difficult due to the limited ability to suppress backgrounds from mis-identified jets. further topics in which b-tagging of hadronic jets is a crucial ingredient are top physics and bsm searches. technical details for these inclusive b-tagging methods are given in section . information about the cms detector is available in [ ]. b-tagging in cms the primary goal of ”b-tagging” is to identify the presence of b-quarks as efficiently as possible while keeping a reasonable purity. two main properties of b-hadron decays are exploited for this purpose: the lifetime of about τ = . ps with cτ = µm which leads to a measurable separation between the primary event vertex and the b decay vertex. secondly, the semileptonic decay modes with a branching ratio of about % per lepton flavour provide a clean signature that can be used for b-identification. production of quarks, either in the hard interaction or as decay products, leads to a a bundle of particles in the final state (leptons and hadrons) which are emitted in about the same direction. this jet of particles can be detected by the tracker and calorimeters. the direction defined by the jet is subsequently used to associate tracks to the jet. the association is done simply by using a cone around the jet direction, defined in pseudo-rapidity η and azimuthal angle φ. tracks are then extrapolated back to the interaction point where the calculation of the impact parameter [ ] is performed. the impact parameter (ip) is defined as the distance between the primary vertex and the point of closest approach of the track to this vertex. as shown in section . , the ip already provides a powerful discrimination between b-jets and non-b-jets. since the measurement of the ip can be distorted by various effects like multiple scattering and wrong hit-to-track associations, it is important to take the measurement’s error into account. therefore, the variable of choice is the ip significance, defined as the ratio value/error. the distribution of the transverse impact parameter significance is shown in figures and for light flavour jets and b-jets, respectively, in various detector misalignment scenarios which are discussed in section . . in these figures, the second track, ordered by the ip significance itself is shown. the first track has a higher probability to suffer from mismeasurements which causes the purity to decrease. it is also possible to use the third track which results in an even better purity at the cost of a lower efficiency. the most simple algorithms to distinguish b-jets from other jets use this ip significance distribution as discrim- inator. more advanced algorithms make use of secondary vertex information [ ]. secondary vertices can be reconstructed in b-jets using the associated tracks, passing well defined quality criteria. a vertex fit [ ] is per- formed and the point of the b-hadron decay is reconstructed with very high precision. the distance between the primary event vertex and the secondary vertex serves as a powerful and robust discriminator for the identification of b-jets [ ]. . detector alignment and performance the calibration and alignment of the detector are of major importance during the startup phase of the experiment. since physicists want to do their analyses as early as possible, it is important to understand the impact of a mis- d impact parameter significance - a rb itr a ry u n its - - - - udsg jets misalignment scenario: none pb- pb- pb- pixel l off startup cms preliminary udsg jets figure : distribution of the transverse impact parameter significance of the second track (ordered by i.p. signifi- cance) for various misalignment scenarios and jet flavours. only light flavour jets are shown here. the term “light flavour jets” corresponds to jets originating from u, d and s quarks as well as from gluons. inclusive tt events have been used. d impact parameter significance - a rb itr a ry u n its - - - - bottom jets misalignment scenario: none pb- pb- pb- pixel l off startup cms preliminary bottom jets figure : as figure but for b-jets instead of light flavour jets. aligned detector on physics results. for this purpose, the following set of scenarios has been defined and the effect on b-tagging has been studied [ ]: • startup: only information from survey measurements, the laser alignment system and cosmic muon tracks can be used to perform a detector alignment. • pb− : the tracker can be aligned by using cosmic muon data and a sample of collision tracks, mainly being isolated hadrons in minimum bias events and muons from the decays of low mass resonances like j/ψ and upsilon. for the pixel detector, it is assumed that the alignment of its larger structures can be improved by a factor of , but that there is no improvement of the module-level alignment. for the strip tracker, it is assumed that the sub-detector positions can be aligned with an accuracy of µm. • pb− : high pt muons from z and w boson decays are available in significant quantity. the misalign- ment of the pixel tracker is expected to be o( µm), and that of the strip tracker o( . . . µm). the tracker can be considered to be aligned with an integrated luminosity of pb− which can probably be achieved within year of detector operation. the effects on the ip significance are shown in figures and . the distribution for b-jets becomes narrower due to the increased error of the measurement. the distribution for light flavour jets is not as much affected but it becomes broader in the startup scenario. this is due to the increased rate of fake tracks or tracks with wrongly associated hits in the first detector layers, which cause pathologically high ip values. the distributions for the different flavours become more similar with increasing misalignment and therefore the separation power is reduced. obviously, this is a rather large effect and it can be expected that purely impact parameter based tagging algorithms are not optimal for early data taking. the performance in terms of misidentification rates depending on b-tagging efficiency is shown for the ”track counting” algorithm [ , ] in figure . this algorithm simply uses the transverse ip significance of the second track as a discriminator and a continuous cut on this variable is applied. b-jet efficiency . . . . . . . . . n o n b -j e t e ff ic ie n cy - - - - udsg jets, trackcounting higheff misalignment scenario: none pb- pb- pb- pixel l off startup cms preliminary udsg jets, trackcounting higheff figure : b-jet efficiency versus non b-jet efficiency for the various misalignment scenarios in case of the track- counting (high efficiency) algorithm, for light flavour jets. inclusive tt events have been used. as mentioned, single tracks and the associated impact parameters can be quite sensitive to mismeasurements of any kind and it is therefore worthwhile to investigate more robust taggers. soft lepton based taggers proved to be very resistant against detector effects [ ], but they are limited by the small fraction of semileptonic b decays (about % per lepton flavour). promising alternatives are secondary vertex based taggers. studies showed that the observables associated to a reconstructed secondary vertex are indeed more robust [ ], since several tracks are combined and outlying tracks are included with smaller weights. for instance, the so-called ”simple secondary vertex” tagger, which only uses the flight distance significance of the secondary vertex as discriminator, turned out to be a promising candidate. after optimizations, this algorithm reaches a b-jet identification efficiency of % at a light flavour misidentification rate of % in an aligned detector. its robustness is visible in figure where the relative performance decrease is shown. it is defined as the ratio of misidentification efficiencies in a misaligned detector with respect to an aligned detector (�mistagmisaligned/� mistag aligned) for various b-tagging algorithms. in the pb − scenario, the simple secondary vertex algorithm has a performance decrease of a factor of less than two, while the most powerful algorithm (in an ideal detector) loses more than a factor of in a misaligned detector. b-jet efficiency . . . . . . . . . re la tiv e p e rf o rm a n ce d e cr e a se udsg jets, pb- scenario b-tagging algorithm: jetprobability simplesecondaryvertex trackcounting higheff trackcounting highpur combinedsecondaryvertex cms preliminary udsg jets, pb- scenario figure : relative performance decrease (�mistagmisaligned/� mistag aligned) in light flavour mistagging rate for several tagging algorithms compared to a perfectly aligned tracker. the plot shows the pb− scenario . ”trackcounting higheff” (”highpur”) refers to the case in which the second (third) track’s ip significance is used as discriminator. the ”combined secondary vertex” algorithm is the most powerful of all algorithms in an ideal detector. it combines all available information from track and vertex observables (section . ) by applying a likelihood method. measurement of the bb cross-section the evaluation of the ability to measure the bb cross-section [ ] is based upon a data sample produced with the pythia [ ] event generator using qcd jets, followed by a complete monte carlo simulation of the cms detector. conditions corresponding to the low-luminosity lhc run with l = · cm− s− have been applied. a total accumulated integrated luminosity of fb− is assumed. events are required to pass the level- trigger selection for single muons with pt > gev/c. at the high-level trigger a muon+b-jets cross channel trigger is used with jet et > gev resulting in a trigger rate of . hz. the offline selection requires a b-tagged jet to be present in the event using the most performant ”combined” b-tagging algorithm [ ] mentioned above. the average b-tagging efficiency in this sample is % in the barrel region and % less in the endcap region. the efficiency degrades to less than % for higher jet energies (et > gev) due to a worse track momentum resolution, increased track multiplicity from fragmentation and more difficult pattern recognition in dense jets. for the measurement of the cross-section, four basic ingredients are necessary: the number of events passing the selection, the integrated luminosity, the signal selection efficiency and the event sample purity (signal fraction). the selected events and the luminosity are directly accessible by measurement. the selection efficiency and purity need to rely on simulation to a certain extent. the absolute predictions given by simulation suffer from large uncertainties, therefore methods relying as little as possible on simulation are used for this purpose. in the analysis presented here, the signal fraction is determined by using the signal and background shapes of the relative transverse momentum of muons with respect to the b-jet. a fit of the muon pt spectrum by the expected shapes for contributions from b, c and light quark events is shown in figure . the normalisations of the three contributions, determined in the fit, represent the corresponding flavour fractions in the sample. the true flavour fractions are well reproduced within statistical errors. further methods to measure efficiencies and the flavour content in event samples are discussed in section . (gev/c)tmuon-btagjet p n um be r of e ve nt s figure : fit of the muon pt spectrum with respect to the closest b-tagged jet. the contributions of tagged muons from b-events (dashed curve), c-events (dot-dashed curve) and light quark events (dotted curve) as defined by the fit are shown. the solid curve is the sum of the three contributions. [ ] the contribution of background from tt events has been estimated to contribute less than % to the selected events. it becomes more pronounced in the high momentum region (pt > gev/c) of the b-spectrum with a contribution of . %. several sources of systematic uncertainties have been taken into account. the largest one is due to a % error on the jet energy scale, which leads to a % uncertainty on the cross-section measurement at et > gev. for very high energies, this error drops to %. the most important remaining uncertainties are: • event selection procedure and monte carlo modeling of the detector, like lepton identification and angular and energy resolutions. this results in a % uncertainty. • b-tagging uncertainties, % • luminosity uncertainty, % • fragmentation modeling, % the total systematic and statistical errors are shown in figure . it is visible that the analysis is limited by the (gev/c)tb tagged jet p c ro ss -s ec tio n un ce rt ai nt y, % - figure : the statistical uncertainty for the cross section measurement (triangles), systematic (squares) uncertainty and total (dots) uncertainty as function of the b-tagged jet transverse momentum for fb− . [ ] systematic error of around % in the low pt region, while the statistical error becomes dominant in the high pt range. the analysis becomes statistically limited at . tev for an assumed integrated luminosity of fb− . performance measurement with data absolute predictions for tagging efficiencies given by the simulation are usually not very reliable. methods to measure the event content and therefore the tagging efficiencies from data have been developed, for example the template fits to the relative muon pt as discussed above. another example is the ”system ” method developed by the d collaboration, which is also being applied in cms [ ]. this method exploits three uncorrelated identifica- tion criteria for b-jets: • the working point of the lifetime tagging algorithm under study • the cut on the relative transverse momentum of the muon with respect to the b-jet • the presence of a second b-jet due to the preferred mode of b-quark pair production in qcd events the various criteria are applied individually or all together leading to a system of eight linear equations, with eight unknowns which are the tagging efficiencies. the method assumes that the efficiency for tagging a jet with both the lifetime tag and the relative muon pt cut can be calculated as the product of the individual efficiencies. the only input from simulation are the correlation factors between the lifetime tag and the muon requirement as well as the ratio of the lifetime tagging efficiencies for b and c+light jets, respectively, corresponding to the two different data samples used to solve the system of equations. more details can be found in [ ]. the result in terms of b-jet tagging efficiency determined with this method is shown in figure . it is visible that the values determined with [gev/c] t jet p b- je t e ffi ci en cy . . . . . . . . . . . expected counting system - cms preliminary pb stat. errors only figure : b-tagging efficiency as a function of jet pt as measured with the counting and system methods. more details on the counting method can be found in [ ]. results are shown with statistical errors for a corresponding integrated luminosity of about pb− . this method agree well with the true values within the indicated errors. another important method to measure the misidentification rates is the use of the negative tail of the impact param- eter distribution. the impact parameter is labelled positive (negative) if the track originates upstream (downstream) with respect to the primary vertex [ ]. in the ideal case, the ip distribution would be symmetric around zero for light flavour jets and only positive for b-jets, since tracks from b-jets are really displaced in the direction of the jet, while tracks from light flavour jets originate at the primary vertex. high ip values of tracks originating at the primary vertex are mostly caused by instrumental mismeasurements or multiple scattering and therefore have an equal opportunity to cause positive or negative signs. in reality however, the distribution for b-jets does also have negative values due to mismeasurements. in addition the distribution for light flavours is not perfectly symmetric because it is affected by displaced processes such as long lived particles (k s, Λ), photon conversions and other effects. the mistag efficiency can then be evaluated using the negative tag rate from multijet processes and a cor- rection factor which needs to be obtained from simulation. studies [ ] show that this method can be applied with a relative precision of % for a light flavour mistag rate of % in case of an integrated luminosity of pb− . another possibility is the use of the large number of top quark events expected at the lhc. it is possible to extract highly enriched b-jet samples from these events based on kinematical constraints exploiting the clear top quark signatures [ ]. the expected precision of this method for fb− ( fb− ) is a relative accuracy of % ( %) on the b-jet identification efficiency in the barrel region and % ( %) in the forward region. conclusions a large number of physics studies like higgs searches and searches for physics beyond the standard model (bsm) depend on efficient and clean identification of b-quark jets, mainly to distinguish these processes from back- grounds. however, not all backgrounds are reducible, so the precise knowledge of the bb production cross-section is critical for these searches. cms will be able to measure the differential bb production cross-section up to . tev. technical details about these methods to identify b-jets have been presented and their behavior under real- istic conditions has been studied. it is necessary to determine the performance of these b-identification algorithms in terms of efficiency and purity using data only, relying as little as possible on the monte carlo simulation. the cms collaboration managed to develop and evaluate all necessary tools to achieve these tasks and is ready for first lhc collisions. references [ ] ua collaboration, ”measurement of the bottom quark production cross section in proton-antiproton colli- sions at √ s = . tev”, phys. lett b , , - 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[ ] cdf collaboration, f. abe et al., ”measurement of the b+ total cross section and b+ differential cross section dσ/dpt in pp̄ collisions at √ s = . tev”, phys. rev. d ( ) . [ ] cdf collaboration, f. abe et al., ”measurement of the b meson differential cross section dσ/dpt in pp̄ collisions at √ s = . tev”, phys. rev. lett. ( ). [ ] d collaboration, s. abachi et al., ”inclusive µ and b-quark production cross-sections in pp̄ collisions at√ s = . tev”, phys. rev. lett. ( ) . [ ] d collaboration, b. abbott et al., ”the bb̄ production cross section and angular correlations in pp̄ collisions at √ s = . tev”, phys. lett. b ( ) . [ ] d collaboration, b. abbott et al., ”cross section for b-jet production in p̄p collisions at √ s = . tev”, phys. rev. lett. ( ) . [ ] cdf collaboration, f. abe et al., ”measurement of the ratio of b quark production cross sections in p̄p collisions at √ s = gev and √ s = gev”, phys. rev. d ( ) . [ ] m. cacciari and p. nason, ”is there a significant excess in bottom hadroproduction at the tevatron?”, phys. rev. lett. (aug, ) . [ ] v. p. andreev, d. b. cline, s. otwinowski, ”measurement of open beauty production at lhc with cms”, cms note / ( ). [ ] d. benedetti, s. cucciarelli, c. hill, j. incandela, s. a. koay, c. riccardi, a. santocchia, a. schmidt, p. torre, and c. weiser, ”observability of higgs produced with top quarks and decaying to bottom quarks”, j. phys. g: nucl. part. phys. ( ), no. , n -n . [ ] the cms collaboration, ”the cms experiment at the cern lhc”, j. inst. ( ) s . [ ] a. rizzi, f. palla, and g. segneri, ”track impact parameter based b-tagging with cms”, cms note / ( ). [ ] t. müller, et. al., ”inclusive secondary vertex reconstruction in jets”, cms note / ( ). [ ] t. speer, k. prokofiev, r. fruehwirth, w. waltenberger, p. vanlaer, ”vertex fitting in the cms tracker”, cms note / ( ). [ ] cms collaboration, ”impact of tracker misalignment on the cms b-tagging performance”, cms pas btv ( ). [ ] t. sjöstrand et al., ”high-energy-physics event generation with pythia . ”, comput. phys. commun. ( ) . [ ] christian weiser, ”a combined secondary vertex based b-tagging algorithm in cms”, cms note / ( ). [ ] cms collaboration, ”performance measurement of b-tagging algorithms using data containing muons within jets”, cms pas btv ( ). [ ] cms collaboration, ”evaluation of udsg mistags for b-tagging using negative tags”, cms pas btv ( ). [ ] steven lowette, jorgen d’hondt, jan heyninck, pascal vanlaer, ”offline calibration of b-jet identification efficiencies”, cms note / ( ). research article hidden-beauty broad resonance𝑌𝑏( ) in thermal qcd j. y. süngü , a. türkan, h. dal, , and e. veli veliev , department of physics, kocaeli university, izmit, turkey özyeğin university, department of natural and mathematical sciences, çekmeköy, istanbul, turkey physik department, technische universität münchen, d- garching, germany faculty of education, kocaeli university, izmit, turkey correspondence should be addressed to j. y. süngü; jaleyil@gmail.com received december ; revised february ; accepted march ; published june academic editor: alexey a. petrov copyright © j. y. süngü et al. this is an open access article distributed under the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. the publication of this article was funded by scoap . in this work, the mass and pole residue of resonance𝑌�푏 is studied by using qcd sum rules approach at finite temperature. resonance𝑌�푏 is described by a diquark-antidiquark tetraquark current, and contributions to operator product expansion are calculated by including qcd condensates up to dimension six. temperature dependencies of the mass 𝑚�푌𝑏 and the pole residue 𝜆�푌𝑏 are investigated. it is seen that near a critical temperature (𝑇�푐 ≃ mev), the values of 𝑚�푌𝑏 and 𝜆�푌𝑏 decrease to % and to % of their values at vacuum. . introduction heavy quarkonia systems provide a unique laboratory to search the interplay between perturbative and nonpertur- bative effects of qcd. they are nonrelativistic systems in which low energy qcd can be investigated via their energy levels, widths, and transition amplitudes [ ]. among these heavy quarkonia states, vector charmonium and bottomo- nium sectors are experimentally studied very well, since they can be detected directly in 𝑒+𝑒− annihilations. in the past decade, observation of a large number of bottomonium-like states in several experiments increased the interest in these structures [ – ]. however, these observed states could not be conveniently explained by the simple 𝑞𝑞 picture of mesons. the presumption of hadrons containing quarks more than the standard quark content (𝑞𝑞 or 𝑞𝑞𝑞) is introduced by a perceptible model for diquarks plus antidiquarks, which was developed by jaffe in [ ]. later maiani, polosa, and their collaborators proposed that the x, y, z mesons are tetraquark systems, in which the diquark-antidiquark pairs are bound together by the qcd color forces [ ]. in this color configuration, diquarks can play a fundamental role in hadron spectroscopy. thus, probing the multiquark matter has been an intensely intriguing research topic in the past twenty years and it may provide significant clues to understand the nonperturbative behavior of qcd. in , belle reported the first evidence of 𝑒+𝑒− 󳨀→Υ( 𝑆)𝜋+𝜋−, Υ( 𝑆)𝜋+𝜋− and first observation for 𝑒+𝑒− 󳨀→Υ( 𝑆)𝜋+𝜋−, Υ( 𝑆)𝐾+𝐾− decays near the peak of the Υ( 𝑆) state at √𝑠 = . gev [ ]. assigning these signals toΥ( 𝑆), the partial widths of decays Υ( 𝑆) 󳨀→ Υ( 𝑆)𝜋+𝜋− andΥ( 𝑆) 󳨀→ Υ( 𝑆)𝜋+𝜋− were measured unusually larger (more than two orders of magnitude) than formerly measured decay widths of Υ(𝑛𝑆) states. following these unusually large partial width measurement, belle measured the cross sections of 𝑒+𝑒− 󳨀→ Υ( 𝑆)𝜋+𝜋−, Υ( 𝑆)𝜋+𝜋− and Υ( 𝑆)𝜋+𝜋− and reported that the resonance observed via these decays does not agree with conventional Υ( 𝑆) line shape. these observations led to the proposal of existence of new exotic hidden-beauty state analogous to broad 𝑌( ) resonance in the charmonium sector, which is a breit-wigner shaped resonance with mass ( . + . − . ± . ) mev/c , and width ( . + . − . ± . ) mev/c , and is called 𝑌�푏( ) [ ]. in literature, there are several approaches to investigate the structure of exotic 𝑌�푏 resonance. in [ ], 𝑌�푏 is considered as a Λ �푏Λ�푏 bound state with a highly large binding energy. in [ , ], 𝑌�푏 is interpreted as a tetraquark and its mass is estimated by using qcd sum rules at vacuum. hindawi advances in high energy physics volume , article id , pages https://doi.org/ . / / https://orcid.org/ - - - https://creativecommons.org/licenses/by/ . / https://doi.org/ . / / advances in high energy physics moreover, it is likely that at very high temperatures within the first microseconds following the big bang, quarks and gluons existed freely in a homogenous medium called the quark-gluon plasma (qgp). one of the first quark-gluon plasma signals proposed in the literature is suppression of𝐽/𝜓 particles [ ]. in , cms collaboration reported that charmonium states 𝜙( 𝑆) and 𝐽/𝜓 melt or were suppressed due to interacting with the hot nuclear matter created in heavy-ion interactions [ , ]. following these observations in the charmonium sector, cms collaboration also reported suppression of bottomonium states, Υ( 𝑆) and Υ( 𝑆) relative to the Υ( 𝑆) ground state [ , ]. the dissociation tempera- tures for theΥstates are expected to be related to their binding energies and are predicted to be 𝑇�푐, . 𝑇�푐 and 𝑇�푐 for theΥ( 𝑆), Υ( 𝑆), and Υ( 𝑆) mesons, respectively, where 𝑇�푐 is the critical temperature for deconfinement [ – ]. in addition to these studies, one of the first investigations on thermal properties of exotic mesons was done in [ ], in which the authors investigated in medium properties of 𝑋( ) under the hypothesis that it is a ++ state or −+ state, but making no assumption on its structure. they estimated that the mass of the ++ molecular state decreases with increasing temperature; the mass of charmonium or tetraquark state is almost stable. inspired by these findings and motivated by the afore- mentioned discussions, we focus on the 𝑌�푏 resonance and its thermal behavior. this paper is organized as follows. in section , theoretical framework of thermal qcd sum rules (tqcdsr) and its application to 𝑌�푏 are presented, and obtained analytical expressions of the mass and pole residue of 𝑌�푏 are given up to dimension six operators. numerical analysis is performed and results are obtained in section . concluding remarks are discussed in section . the explicit forms of the spectral densities are written in appendix. . finite temperature sum rules for tetraquark assignment qcd sum rules (qcdsr) approach is based on wilson’s operator product expansion (ope) which was adapted by shifman, vainshtein, and zakharov [ ] and applied with remarkable success to estimate a large variety of properties of all low-lying hadronic states [ – ]. later, this model is extended to its thermal version that is firstly proposed by bochkarev and shaposnikov and led to many successful applications in qcd at 𝑇 ̸= [ – ]. very recently, in [ ], the authors claimed that any qcdsr study on tetraquark states should contain 𝑂(𝛼 �푠 ) contributions to ope, which are unknown. it is a very important and strong argument for studying tetraquark states within qcdsr; however, those terms and their thermal behaviors are not known, and their calculation is beyond the scope of this work. thus we follow the traditional sum rules to investigate the thermal behavior of hadronic parameters of 𝑌�푏, which were used very successfully in predicting properties of tetraquark states as well. in this work, we proceed with traditional sum rules analysis by using a tetraquark current, following several successful applications to exotic hadrons [ – ]. in this section, the mass and pole residue of the exotic 𝑌�푏 resonance are studied by interpreting it as a bound [𝑏𝑠][𝑏𝑠] tetraquark via tqcdsr technique which starts with the two point correlation function Π�휇] (𝑞, 𝑇) = 𝑖∫ 𝑑 𝑥𝑒�푖�푞⋅�푥 ⟨Ψ 󵄨󵄨󵄨󵄨󵄨t {𝜂�휇 (𝑥)𝜂†] ( )}󵄨󵄨󵄨󵄨󵄨 Ψ⟩ , ( ) where Ψ represents the hot medium state, 𝜂�휇(𝑥) is the interpolating current of the 𝑌�푏 state, and t denotes the time ordered product. the thermal average of any operator 𝑂 in thermal equilibrium is given as ⟨𝑂⟩ = 𝑇𝑟 (𝑒 −�훽h𝑂) 𝑇𝑟 (𝑒−�훽h) , ( ) where h is the qcd hamiltonian, and 𝛽 = /𝑇 is inverse of the temperature, and 𝑇 is the temperature of the heat bath. chosen current 𝜂�휇(𝑥) must contain all the information of the related meson, like quantum numbers, quark contents and so on. in the diquark-antidiquark picture, tetraquark current interpreting 𝑌�푏 can be chosen as [ ] 𝜂�휇 (𝑥) = 𝑖𝜖𝜖√ {[𝑠 �푇 �푎 (𝑥) 𝐶𝛾 𝑄�푏 (𝑥)] [𝑠�푑 (𝑥) 𝛾�휇𝛾 𝐶𝑄�푇�푒 (𝑥)] + [𝑠�푇�푎 (𝑥)𝐶𝛾 𝛾�휇𝑄�푏 (𝑥)] [𝑠�푑 (𝑥)𝛾 𝐶𝑄�푇�푒 (𝑥)]} , ( ) where 𝑄 = 𝑏, 𝐶 is the charge conjugation matrix and𝑎, 𝑏, 𝑐, 𝑑, 𝑒 are color indices. shorthand notations 𝜖 = 𝜖�푎�푏�푐 and𝜖 = 𝜖�푑�푒�푐 are also employed in ( ). in tqcdsr, the correlation function given in ( ) is cal- culated twice, as in two different regions corresponding two perspectives, namely the physical side (or phenomenological side) and the qcd side (or ope side). by equating these two approaches, the sum rules for the hadronic properties of the exotic state under investigation are achieved. to derive mass and pole residue via tqcdsr, the correlation function is calculated in terms of hadronic degrees of freedoms in the physical side. a complete set of intermediate physical states possessing the same quantum number as the inter- polating current are inserted into ( ), and integral over 𝑥 is handled. after these manipulations, the correlation function is obtained as Πphys�휇] (𝑞, 𝑇) = ⟨Ψ 󵄨󵄨󵄨󵄨󵄨𝜂�휇󵄨󵄨󵄨󵄨󵄨 𝑌�푏 (𝑞)⟩�푇 ⟨𝑌�푏 (𝑞) 󵄨󵄨󵄨󵄨󵄨𝜂†]󵄨󵄨󵄨󵄨󵄨 Ψ⟩�푇𝑚 �푌𝑏 (𝑇) − 𝑞 + 𝑠𝑢𝑏𝑡𝑟𝑎𝑐𝑡𝑒𝑑 𝑡𝑒𝑟𝑚𝑠, ( ) here 𝑚�푌𝑏(𝑇) is the temperature-dependent mass of 𝑌�푏 meson. temperature-dependent pole residue 𝜆�푌𝑏(𝑇) is defined in terms of matrix element as ⟨Ψ 󵄨󵄨󵄨󵄨󵄨𝜂�휇󵄨󵄨󵄨󵄨󵄨 𝑌�푏 (𝑞)⟩�푇 = 𝜆�푌𝑏 (𝑇) 𝑚�푌𝑏 (𝑇) 𝜀�휇, ( ) where 𝜀�휇 is the polarization vector of the 𝑌�푏 satisfying 𝜀�휇𝜀∗] = −𝑔�휇] + 𝑞�휇𝑞]𝑚 �푌𝑏 (𝑇). ( ) advances in high energy physics after employing polarization relations, the correlation func- tion is written in terms of lorentz structures in the form Πphys�휇] (𝑞, 𝑇) = 𝑚 �푌𝑏 (𝑇) 𝜆 �푌𝑏 (𝑇)𝑚 �푌𝑏 (𝑇) − 𝑞 (−𝑔�휇] + 𝑞�휇𝑞] 𝑚 �푌𝑏 (𝑇)) + . . . , ( ) where dots denote the contributions coming from the contin- uum and higher states. to obtain the sum rules, coefficient of any lorentz structure can be used. in this work, coefficients of 𝑔�휇] are chosen to construct the sum rules and the standard borel transformation with respect to 𝑞 is applied to suppress the unwanted contributions. the final form of the physical side is obtained as b (𝑞 ) Πphys (𝑞, 𝑇) = 𝑚 �푌𝑏 (𝑇) 𝜆 �푌𝑏 (𝑇) 𝑒−�푚 𝑌𝑏(�푇)/�푀 , ( ) here 𝑀 is the borel mass parameter. in the qcd side,Πqcd�휇] (𝑞, 𝑇) is calculated in terms of quark-gluon degrees of freedom and can be separated into two parts over the lorentz structures as Πqcd�휇] (𝑞, 𝑇) = Πqcd�푆 (𝑞 , 𝑇) 𝑞�휇𝑞]𝑞 + Πqcd�푉 (𝑞 , 𝑇) (−𝑔�휇] + 𝑞�휇𝑞]𝑞 ) , ( ) where Πqcd �푆 (𝑞 , 𝑇) and Πqcd �푉 (𝑞 , 𝑇) are invariant functions connected with the scalar and vector currents, respectively. in the rest framework of 𝑌�푏 (q = ), Πqcd�푉 (𝑞 , 𝑇) can be expressed as a dispersion integral, Πqcd�푉 (𝑞 , 𝑇) = ∫ �푠 (�푇) (�푚𝑏+�푚𝑠) 𝜌qcd (𝑠, 𝑇) 𝑠 − 𝑞 𝑑𝑠 + ⋅ ⋅ ⋅ , ( ) where corresponding spectral density is described as 𝜌qcd (𝑠, 𝑇) = 𝜋im Πqcd�푉 (𝑠, 𝑇) . ( ) the spectral density can be separated in terms of operator dimensions as 𝜌qcd (𝑠, 𝑇) = 𝜌pert. (𝑠) + 𝜌⟨�푞�푞⟩ (𝑠, 𝑇) + 𝜌⟨�퐺 ⟩+⟨Θ ⟩ (𝑠, 𝑇) + 𝜌⟨�푞�퐺�푞⟩ (𝑠, 𝑇) + 𝜌⟨�푞�푞⟩ (𝑠, 𝑇) . ( ) in order to obtain the expressions of these spectral density terms, the current expression given in ( ) is inserted into the correlation function given in ( ) and then the heavy and light quark fields are contracted, and the correlation function is written in terms of quark propagators as Πqcd�휇] (𝑞, 𝑇) = − 𝑖 ∫𝑑 𝑥𝑒�푖�푞⋅�푥 ⋅ 𝜖𝜖𝜖�耠𝜖�耠 ⟨{tr [𝛾�휇𝛾 𝑆�푎�푎󸀠�푏 (−𝑥) 𝛾 𝛾]𝑆�푏�푏󸀠�푠 (−𝑥)] × tr [𝛾 𝑆�푑�푑󸀠�푠 (𝑥) 𝛾 𝑆�푒�푒󸀠�푏 (𝑥)] + tr [𝛾 𝑆�푎�푎󸀠�푏 (−𝑥) 𝛾 𝑆�푏�푏󸀠�푠 (−𝑥)𝛾�휇] × tr [𝛾 𝑆�푑�푑󸀠�푠 (𝑥) 𝛾 𝑆�푒�푒󸀠�푏 (𝑥) 𝛾]𝛾 𝑆�푏�푏󸀠�푏 (𝑥)] + tr [𝛾 𝑆�푎�푎󸀠�푏 (−𝑥) 𝛾 𝛾] × 𝑆�푏�푏󸀠�푠 (−𝑥)] ⋅ tr [𝛾 𝑆�푑�푑󸀠�푠 (𝑥)𝛾 𝛾�휇𝑆�푒�푒󸀠�푏 (𝑥)] + tr [𝛾 𝑆�푎�푎󸀠�푏 (−𝑥) 𝛾 × 𝑆�푏�푏󸀠�푠 (−𝑥)] ⋅ tr [𝛾 𝑆�푑�푑󸀠�푠 (−𝑥)𝛾 𝑆�푒�푒󸀠�푏 (𝑥) 𝛾]]}⟩ �푇 , ( ) where 𝑆�푖�푗 �푠,�푏 (𝑥) are the full quark propagators and 𝑆�푖�푗 �푠,�푏 (𝑥) = 𝐶𝑆�푖�푗�푇 �푠,�푏 (𝑥)𝐶 is used. the quark propagators are given in terms of the quark and gluon condensates [ ]. at finite temperatures, additional operators arise due to the breaking of lorentz invariance by the choice of thermal rest frame. thus, the residual𝑂( ) invariance brings additional operators to the quark propagator at finite temperature. the expected behavior of the thermal averages of these new operators is opposite of those of the lorentz invariant old ones [ ]. the heavy-quark propagator in coordinate space can be expressed as 𝑆�푖�푗 �푏 (𝑥) = 𝑖 ∫ 𝑑 𝑘( 𝜋) 𝑒 −�푖�푘⋅�푥 [ [ 𝛿�푖�푗 (�𝑘 + 𝑚�푏) 𝑘 − 𝑚 �푏 − 𝑔𝐺 �훼�훽 �푖�푗 𝜎�훼�훽 (�𝑘 + 𝑚�푏) + (�𝑘 + 𝑚�푏) 𝜎�훼�훽 (𝑘 − 𝑚 �푏 ) +𝑔 𝐺�퐴�훼�훽𝐺�훼�훽�퐴 𝛿�푖�푗𝑚�푏 𝑘 + 𝑚�푏�𝑘 (𝑘 − 𝑚 �푏 ) + . . .] , ( ) and the thermal light quark propagator is chosen as 𝑆�푖�푗�푠 (𝑥) = 𝑖 �𝑥 𝜋 𝑥 𝛿�푖�푗 − 𝑚�푠 𝜋 𝑥 𝛿�푖�푗 − ⟨𝑠𝑠⟩ 𝛿�푖�푗 − 𝑥 ⋅ 𝑚 ⟨𝑠𝑠⟩ [ − 𝑖𝑚�푠 �𝑥] 𝛿�푖�푗 + 𝑖 [�𝑥 ( 𝑚�푠 ⟨𝑠𝑠⟩ − ⟨𝑢�휇Θ�푓�휇]𝑢]⟩) + (𝑢 ⋅ 𝑥) �𝑢 ⟨𝑢�휇Θ�푓�휇]𝑢]⟩] 𝛿�푖�푗 − 𝑖𝑔�푠𝐺�훼�훽�푖�푗 𝜋 𝑥 (�𝑥𝜎�훼�훽 + 𝜎�훼�훽�𝑥) , ( ) where 𝐺�훼�훽 �푖�푗 ≡ 𝐺�훼�훽 �퐴 𝑡�퐴�푖�푗 is the external gluon field, 𝑡�퐴�푖�푗 = 𝜆�퐴�푖�푗/ with 𝜆�퐴�푖�푗 gell-mann matrices, 𝐴 = , , . . . , symbolizes color indices, 𝑚�푠 implies the strange quark mass, 𝑢�휇 is advances in high energy physics the four-velocity of the heat bath, ⟨𝑞𝑞⟩ is the temperature- dependent light quark condensate, and Θ�푓�휇] is the fermionic part of the energy-momentum tensor. furthermore, the gluon condensate related to the gluonic part of the energy- momentum tensor Θ�푔 �훼�훽 is expressed via relation [ ]: ⟨𝑇𝑟�푐𝐺�훼�훽𝐺�휆�휎⟩�푇 = (𝑔�훼�휆𝑔�훽�휎 − 𝑔�훼�휎𝑔�훽�휆) 𝐴 − (𝑢�훼𝑢�휆𝑔�훽�휎 − 𝑢�훼𝑢�휎𝑔�훽�휆 − 𝑢�훽𝑢�휆𝑔�훼�휎 + 𝑢�훽𝑢�휎𝑔�훼�휆) 𝐵, ( ) where 𝐴 and 𝐵 coefficients are 𝐴 = ⟨𝐺�푎�훼�훽𝐺�푎�훼�훽⟩�푇 + ⟨𝑢�훼Θ�푔�훼�훽𝑢�훽⟩�푇 , 𝐵 = ⟨𝑢�훼Θ�푔�훼�훽𝑢�훽⟩�푇 . ( ) in order to remove contributions originating from higher states, the standard borel transformation with respect to 𝑞 is applied in the qcd side as well. by equating the coefficients of the selected structure 𝑔�휇] in both physical and qcd sides, and by employing the quark hadron duality ansatz up to a temperature-dependent continuum threshold 𝑠 (𝑇), the final sum rules for 𝑌�푏 are derived as 𝑚 �푌𝑏 (𝑇) 𝜆 �푌𝑏 (𝑇) 𝑒−�푚 𝑌𝑏(�푇)/�푀 = ∫�푠 (�푇) (�푚𝑏+�푚𝑠) 𝑑𝑠 𝜌qcd (𝑠, 𝑇) 𝑒−�푠/�푀 . ( ) to find the mass via tqcdsr, one should expel the hadronic coupling constant from the sum rules. it is commonly done by dividing the derivative of the sum rule given in ( ) with respect to (−𝑀− ) to itself. following these steps, the temperature-dependent mass is obtained as 𝑚 �푌𝑏 (𝑇) = ∫�푠 (�푇) (�푚𝑏+�푚𝑠) 𝑑𝑠 𝑠𝜌qcd (𝑠, 𝑇) 𝑒−�푠/�푀 ∫�푠 (�푇) (�푚𝑏+�푚𝑠) 𝑑𝑠 𝜌qcd (𝑠, 𝑇) 𝑒−�푠/�푀 , ( ) where the thermal continuum threshold 𝑠 (𝑇) is related to continuum threshold 𝑠 at vacuum via relation 𝑠 (𝑇) = 𝑠 [ − ( 𝑇𝑇�푐 ) ] + (𝑚�푏 + 𝑚�푠) ( 𝑇𝑇�푐 ) ( ) [ , ]. for compactness, the explicit forms of spectral densities are presented in appendix. . phenomenological analysis in this section, the phenomenological analysis of sum rules obtained in ( ) and ( ) is presented. first, the input parame- ters and temperature dependance of relevant condensates are given. following, the working regions of the obtained sum rules at vacuum are analyzed. the behavior of qcd sum rules at 𝑇 = is used to test the reliability of our analysis. . . input parameters. during the calculations, input param- eters given in table are used. in addition to these input parameters, temperature-dependent quark and gluon con- densates, and the energy density expressions are necessary. the thermal quark condensate is chosen as ⟨𝑞𝑞⟩ = ⟨ 󵄨󵄨󵄨󵄨𝑞𝑞󵄨󵄨󵄨󵄨 ⟩ + exp ( . ( . [ /gev ] 𝑇 + . [ /gev] 𝑇 − )), ( ) where ⟨ |𝑞𝑞| ⟩ is the light quark condensate at vacuum and which is credible up to a critical temperature 𝑇�푐 = mev. the expression given in ( ) is obtained in [ , ] from the lattice qcd results given in [ , ]. the temperature- dependent gluon condensate is parameterized via [ , ] ⟨𝐺 ⟩ = ⟨ 󵄨󵄨󵄨󵄨󵄨𝐺 󵄨󵄨󵄨󵄨󵄨 ⟩ ⋅ [ − . ( 𝑇𝑇�푐 ) . + . ( 𝑇𝑇�푐 ) . ] , ( ) where ⟨ |𝐺 | ⟩ is the gluon condensate in vacuum state and 𝐺 = 𝐺�퐴�훼�훽𝐺�훼�훽�퐴 . additionally, for the gluonic and fermionic parts of the energy density, the following parametrization is used [ ] ⟨Θ�푔 ⟩ = ⟨Θ�푓 ⟩ = 𝑇 exp ( . [ gev ] 𝑇 − . [ gev ] 𝑇) − . [ gev ] 𝑇 , ( ) which is extracted from the lattice qcd data in [ ]. . . analysis of sum rules at 𝑇 = . in order to get reliable results, obtained sum rules should be tested at vacuum, and the working regions of the parameters 𝑠 and 𝑀 should be determined. within the working regions of 𝑠 and 𝑀 , convergence of ope and dominance of pole contributions should be assured. in addition, the obtained physical results should be independent of small variations of these param- eters. convergence of the ope is tested by the following advances in high energy physics pert m (ge６ ) . . . . . po le x c on tin uu m pole continuum m (ge６ ) . . . . . o pe te rm s . + ⟨sＭ⟩ +⟨g ⟩ + ⟨ ⟩ + ⟨s＇Ｍ⟩ + ⟨sＭ⟩ figure : the ope convergence of the sum rules: the ratio of the sum of the contributions up to specified dimension to the total contribution is plotted with respect to 𝑀 at 𝑠 = gev , 𝑇 = (left). pole dominance of the sum rules: relative contributions of the pole (blue) and continuum (red-dashed) versus to the borel parameter 𝑀 at 𝑠 = gev ,𝑇 = (right). table : input parameters [ – ]. 𝑚�푠 = ( . ± . ) mev𝑚�푏 = ( . ± . ) gev𝑚 = ( . ± . ) gev ⟨𝑠𝑠⟩ = − . × ( . ± . ) gev ⟨ 󵄨󵄨󵄨󵄨󵄨󵄨󵄨 𝜋𝛼�푠𝐺 󵄨󵄨󵄨󵄨󵄨󵄨󵄨 ⟩ = ( . ) gev criterion. the contribution of the highest order operator in the ope should be very small compared to the total contribution. in figure , the ratio of the sum of the terms up to the specified dimension to the total contribution is plotted to test the ope convergence. it is seen that all higher order terms contribute less than the perturbative part for 𝑀 ≥ gev . on the other hand, dominance of the pole contribution is tested as follows. the contribution coming from the pole of the ground state should be greater than the contribution of the continuum. in this work, the aforementioned ratio is pc = Π (𝑀 max, 𝑠 ) Π (𝑀 max, ∞) > . , ( ) when 𝑀 ≤ gev as can be seen in figure . after checking these criteria, the working regions of the parameters𝑀 and 𝑠 are determined as gev ≤ 𝑀 ≤ gev ; gev ≤ 𝑠 ≤ gev , ( ) which is also consistent with 𝑠 ≃ (𝑚�퐻+ . gev) norm [ ]. within these working regions, the variations of the mass of 𝑌�푏 with respect to 𝑀 and 𝑠 are plotted in figure . it is seen that the mass is stable with respect to variations of 𝑀 and 𝑠 . table : results obtained in this work for the mass of 𝑌�푏 at 𝑇 = , in comparison with literature. 𝑚�푌𝑏(mev) present work + − experiment . + . − . [ ] qcdsr ± [ ] ± [ ] . results and discussions following the analysis presented in previous section, the mass of the ground state estimated by the tetraquark current given in ( ) at 𝑇 = is presented together with other results from literature in table . it is seen that our results agree with other theoretical estimates and also with the experimental data on𝑌�푏( ) [ , , ]. thus, the broad resonance 𝑌�푏 can be described by the tetraquark current given in ( ), and our analysis can be extended to finite temperatures. to analyze the thermal properties of 𝑌�푏( ) reso- nance, the temperature dependencies of the mass and the pole residue of 𝑌�푏 are plotted in figure . it is seen that the mass and the pole residue of 𝑌�푏 stay monotonous until 𝑇 ≅ . gev. however, after this point, they begin to decrease promptly with increasing temperature. at the vicinity of the critical (or so called deconfinement) temperature, the mass reaches nearly % of its vacuum value. on the other hand, the pole residue decreased to % of its value at vacuum as shown in figure . our predictions presented in figure are in good agreement with other qcd sum rules analysis on ther- mal behaviors of conventional or exotic hadrons [ – ]. however in [ ], authors predicted a decrease of % in the mass of molecular ++ state, and no change in the mass of charmonium −+ state, even beyond hagedorn temperature𝑇�퐻 ∼ mev. since the decay properties also depend on temperature, and while the mass and pole residue diminish, advances in high energy physics . . . . . . . . . . . . . . . . . m (ge６ ) s = ge６ = ge６ s m y  (g ev ) s (ge６ ) m y  (g ev ) m = ge６ m = ge６ m = ge６ figure : mass of 𝑌�푏 as a function of 𝑀 (left) and 𝑠 (right). s = ge６ s = ge６ s = ge６ s = ge６ m y  (t )/ m y  ( ) t/tc . . . . . . . . . . . . . . . . t/tc . . . . . .  y  (t )/  y  ( ) figure : the mass (left) and pole residue (right) of 𝑌�푏 as a function of temperature. the decay width might increase with increasing temperature [ ] and decay widths at finite temperature should also be investigated. however the current status of 𝑌�푏 resonance is very complicated, since it is very close to Υ( 𝑆) state. thus studying its decays requires establishment of a good model in the hidden-beauty sector. finally, we would like to highlight the following remarks: (i) we observed that the mass (the pole residue) of exotic𝑌�푏( ) state starts to decrease near 𝑇/𝑇�푐 ≃ . . (ii) both quantities tend to diminish with increasing temperature up to critical temperature 𝑇�푐. (iii) even though the sum rules at 𝑇 = estimates the mass of 𝑌�푏 consistent with experimental data, more theoretical efforts are required to discriminate 𝑌�푏 andΥ( 𝑆). (iv) in order to get more reliable results on tetraquarks from qcd sum rules, o(𝛼 �푠 ) contributions suggested in [ ] should be investigated. in summary, we revisited the hidden-beauty exotic state𝑌�푏 and studied its properties at vacuum and finite temper- atures. to describe the hot medium effects to the hadronic parameters of the resonance 𝑌�푏, tqcdsr method is used considering contributions of condensates up to dimension six. our results for 𝑇 = are in reasonable agreement with the available experimental data and other qcd studies in the literature. numerical findings show that 𝑌�푏 can be well described by a scalar-vector tetraquark current. in the literature, remarkable drop in the values of the mass and the pole residue in hot medium was regarded as the signal of the qgp, which is called the fifth state of matter, phase transition. we hope that precise spectroscopic measurements in the exotic bottomonium sector can be done at super-b factories, and this might provide conclusive answers on the nature and thermal behaviors of the exotic states. appendix thermal spectral density 𝜌�푄�퐶�퐷(𝑠,𝑇) for 𝑌�푏 state in this appendix, the explicit forms of the spectral densities obtained in this work are presented. the expressions for𝜌pert.(𝑠) and 𝜌nonpert.(𝑠, 𝑇) areshown below as integrals advances in high energy physics over the feynman parameters 𝑧 and 𝑤, where 𝜃 is the step function, 𝜌pert. (𝑠) = 𝜋 ∫ 𝑑𝑧 ∫ −�푧 𝑑𝑤 𝜅 𝜉 {[−𝜅𝑚 �푏 (𝑧 + 𝑤) + 𝑠𝑧𝑤𝜉] [𝜅 𝑚 �푏𝑧𝑤 (𝑧 + 𝑤) [𝑤 + (− + 𝑤) 𝑤 + 𝑧 (− + 𝑤)] − 𝜅𝑚 �푏 [ 𝑚 �푠Φ [ (− + 𝑧) 𝑧 (− + 𝑧) 𝑤 + 𝑤 ] + 𝑠𝑧 𝑤 ( (− + 𝑧) 𝑧 + (− + 𝑧) 𝑤 + 𝑤 )] 𝜉 +𝑠𝑧𝑤 ( 𝑚 �푠Φ + 𝑠𝑧 𝑤 ) 𝜉 ]} 𝜃 [𝐿 (𝑠, 𝑤, 𝑧)] , (a. ) 𝜌⟨�푠�푠⟩ (𝑠, 𝑇) = ⟨𝑠𝑠⟩ 𝜋 ∫ 𝑑𝑧 ∫ −�푧 𝑑𝑤 𝜅 {[𝜅 𝑚 �푏𝑤 (𝑧 + 𝑤) + 𝜅 𝑚 �푏𝑚�푠 (𝑧 + 𝑤) [ 𝑧 + (− + 𝑤) 𝑤 + 𝑧 (− + 𝑤) 𝑤 (− + 𝑤) +𝑧 (− + 𝑤) + 𝑧 [ + 𝑤 (− + 𝑤)]] − 𝜅 𝑚 �푏𝑧 (𝑧 + 𝑤) (𝑚 �푠Φ + 𝑠𝑤 ) 𝜉 −𝜅𝑚 �푏𝑚�푠𝑠𝑧𝑤 [ 𝑧 + (− + 𝑤) 𝑤 + 𝑧 (− + 𝑤) + 𝑧 (− + 𝑤) 𝑤 (− + 𝑤) +𝑧 [ + 𝑤 (− + 𝑤)]] 𝜉 + 𝜅𝑚�푏𝑠𝑧 𝑤 (𝑚 �푠Φ + 𝑠𝑤 ) 𝜉 + 𝑚�푠𝑠 𝑧 𝑤 (𝑧 + (− + 𝑤) 𝑤 + 𝑧 (− + 𝑤)) 𝜉 ]}𝜃 [𝐿 (𝑠, 𝑤, 𝑧)] , (a. ) 𝜌⟨�퐺 ⟩+⟨Θ ⟩ (𝑠, 𝑇) = 𝜋 ∫ 𝑑𝑧 ∫ −�푧 𝑑𝑤 𝜅 𝜉 { 𝜋 ⟨Θ�푓 ⟩ 𝑧𝑤𝜉 [𝑚 �푏Φ (𝑧 + 𝑤) × [ (− + 𝑧) 𝑧 + (− + 𝑧) 𝑤 + 𝑤 ] + 𝑚 �푏Φ𝑠𝑧𝑤 [− (− + 𝑧) 𝑧 + 𝑤 − 𝑧𝑤 − 𝑤 ] 𝜉 + 𝑠 𝑧 𝑤 𝜉 ] − 𝑔 �푠 ⟨Θ�푔 ⟩ [ 𝑚 �푏Φ 𝑧𝑤 (𝑧 + 𝑤) [ (− + 𝑧) 𝑧 + (− + 𝑧) 𝑧 (− + 𝑧) 𝑤 + (− + 𝑧) (− + 𝑧) 𝑤 + (− + 𝑧) 𝑤 + 𝑤 ] − 𝑚 �푏Φ𝑠𝑧 𝑤 [ (− + 𝑧) 𝑧 + (− + 𝑧) 𝑧 (− + 𝑧) 𝑤 + [ + 𝑧 (− + 𝑧)]𝑤 + (− + 𝑧) 𝑤 + 𝑤 ] 𝜉 − 𝑚 �푏𝑚�푠Φ (𝑧 + 𝑤) 𝜉 + 𝑚�푏𝑚�푠Φ 𝑠𝑧𝑧 (𝑧 + 𝑧𝑤 + 𝑤 ) 𝜉 + 𝑠 𝑧 𝑤 (𝑧 + 𝑤) 𝜉 ] + ⟨𝛼�푠𝐺 𝜋 ⟩ 𝜋 [𝜅𝑚 �푏 {− 𝑚 �푠Φ [ (− + 𝑧) 𝑧 + 𝑧 𝑤 + (− + 𝑧) 𝑤 + 𝑤 ] +𝑠𝑧 𝑤 [ (− + 𝑧) 𝑧 (− + 𝑧) + 𝑧 [ + 𝑧 (− + 𝑧)]𝑤 + [ + 𝑧 (− + 𝑧)]𝑤 (− + 𝑧) 𝑤 + 𝑤 ]}𝜉 − 𝜅 𝑚 �푏𝑚�푠 (𝑧 + 𝑤) (𝑧 − 𝑧𝑤 + 𝑤 ) 𝜉 − 𝑠 𝑧 𝑤 (𝑧 + 𝑤) 𝜉 + 𝜉 𝑚�푏𝑧𝑤 [𝑚 �푏 (𝑧 + 𝑤) ( (− + 𝑧) 𝑧 (− + 𝑧) + 𝑧 [ + 𝑧 (− + 𝑧)] 𝑤 + [ + 𝑧 (− + 𝑧)]𝑤 (− + 𝑧) + 𝑤 ) + 𝑚�푠𝑠 ( 𝑧 − 𝑧𝑤 + 𝑤 ) 𝜉 ]]}𝜃 [𝐿 (𝑠, 𝑤, 𝑧)] (a. ) 𝜌⟨�푠�퐺�푠⟩ (𝑠, 𝑇) = 𝑚�푠𝑚 ⟨𝑠𝑠⟩ 𝜋 {∫ 𝑑𝑧 { 𝑚 �푏 + 𝑠 (𝑧 − ) 𝑧𝜃 [𝐿�耠 (𝑠, 𝑧)]} + ∫ 𝑑𝑧 ∫ −�푧 𝑑𝑤 𝜅 × {𝑧𝑤𝜉 [𝜅𝑚 �푏 [ 𝑧 + (𝑤 − ) 𝑤 + 𝑧 ( 𝑤 − )] − 𝑠𝑧𝑤𝜉 ]𝜃 [𝐿 (𝑠, 𝑤, 𝑧)]}} , (a. ) 𝜌⟨�푠�푠⟩ (𝑠, 𝑇) = ⟨𝑠𝑠⟩ 𝜋 {∫ 𝑑𝑧 [ 𝑚 �푏𝜋 + 𝑔 �푠 𝑚�푏𝑚�푠𝑧 + 𝜋 ( 𝑚 �푠 + 𝑠) (𝑧 − ) 𝑧] 𝜃 [𝐿�耠 (𝑠, 𝑧)] + 𝑔 �푠 ∫ 𝑑𝑧 ∫ −�푧 𝑑𝑤𝑧𝑤𝜉 𝜅 × [ 𝜅𝑚 �푏 [ 𝑧 + (𝑤 − ) 𝑤 + 𝑧 (− + 𝑤)] − 𝑠𝑧𝑤𝜉 ]𝜃 [𝐿 (𝑠, 𝑤, 𝑧)]} , (a. ) where explicit expressions of the functions 𝐿(𝑠, 𝑤, 𝑧) and𝐿�耠(𝑠, 𝑧) are 𝐿 [(𝑠, 𝑤, 𝑧) = 𝜅− (− + 𝑤) [(− + 𝑤) 𝑤 + (− + 𝑤) 𝑤𝑧 + (− + 𝑤) 𝑧 − 𝑠𝑤𝑧𝜉 + 𝑧 𝑚 �푏] , (a. ) 𝐿�耠 (𝑠, 𝑧) = 𝑠𝑧 ( − 𝑧) − 𝑚 �푏. 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} } l. arruda, a. pomés published biology, medicine international archives of allergy and immunology cockroaches are considered to be among the oldest insects on our planet, predating dinosaurs by more than million years, and humans by more than million ( ). some fossils attributed to cockroaches date back to the carboniferous period, around million b.c. however, an uncertain evolutionary link between cockroach-like fossils from the carboniferous period (paleozoic era), and “modern” cockroaches, originated in the cretaceous period (mesozoic era) as did most other insects, has also… expand view on pubmed karger.com save to library create alert cite launch research feed share this paper citationsbackground citations view all topics from this paper dictyoptera allergens sensitization (observable entity) dinosaurs malignant neoplasm of breast cloning, molecular ships parasites diseases of inner ear structure of parenchyma of lung forests acclimatization lung diseases recombinants tropical spastic paraparesis citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency in defence of the world’s most reviled invertebrate ‘bugs’ e. small biology view excerpt, cites background save alert research feed assessment of hymenoptera and non-hymenoptera insect bite and sting allergy among patients of tropical region of west bengal, india arghya laha, tania sarkar, + authors s. podder biology, medicine journal of medical entomology view excerpts, cites background save alert research feed analysis of environmental allergen components of the american cockroach in taiwan. mey-fann lee, y. chen, chu-hui chiang, shyh-jye lin, pei-pong song biology, medicine annals of allergy, asthma & immunology : official publication of the american college of allergy, asthma, & immunology pdf save alert research feed recombinant allergens for diagnosis of cockroach allergy l. arruda, m. barbosa, a. santos, a. s. moreno, m. chapman, a. pomés biology, medicine current allergy and asthma reports save alert research feed investigating cockroach allergens: aiming to improve diagnosis and treatment of cockroach allergic patients. a. pomés, l. k. arruda medicine methods save alert research feed variability in german cockroach extract composition greatly impacts t cell potency in cockroach-allergic donors giovanni birrueta, a. frazier, + authors v. schulten biology, medicine front. immunol. view excerpt, cites background save alert research feed allergenic extracts to diagnose and treat sensitivity to insect venoms and inhaled allergens. t. khurana, jennifer bridgewater, r. rabin biology, medicine annals of allergy, asthma & immunology : official publication of the american college of allergy, asthma, & immunology pdf save alert research feed cockroach allergy and allergen-specific immunotherapy in asthma: potential and pitfalls g. bassirpour, e. zoratti medicine current opinion in allergy and clinical immunology save alert research feed gm-csf produced by the airway epithelium is required for sensitization to cockroach allergen alyssa sheih, w. c. parks, s. ziegler medicine mucosal immunology pdf save alert research feed references showing - of references sort byrelevance most influenced papers recency domestic and non-domestic cockroaches: facts versus received ideas ph. grandcolas biology save alert research feed integrated suppression of synanthropic cockroaches. c. schal, r. hamilton biology, medicine annual review of entomology pdf save alert research feed insect allergy--preliminary studies of the cockroach. h. bernton, h. brown biology, medicine the journal of allergy save alert research feed cockroach allergens and asthma. l. arruda, l. vailes, v. ferriani, a. santos, a. pomés, m. chapman medicine the journal of allergy and clinical immunology pdf save alert research feed molecular basis of arthropod cross-reactivity: ige-binding cross-reactive epitopes of shrimp, house dust mite and cockroach tropomyosins r. ayuso, g. reese, s. leong-kee, m. plante, s. lehrer medicine, biology international archives of allergy and immunology save alert research feed identification of novel allergenic components from german cockroach fecal extract by a proteomic approach k. jeong, chung-ryul kim, jina park, in-soo han, jung-won park, t. yong medicine, biology international archives of allergy and immunology save alert research feed cross-reactive ige antibody responses to tropomyosins from ascaris lumbricoides and cockroach. a. santos, g. m. rocha, + authors l. arruda biology, medicine the journal of allergy and clinical immunology pdf save alert research feed ecology and elimination of cockroaches and allergens in the home. p. eggleston, l. arruda biology, medicine the journal of allergy and clinical immunology pdf save alert research feed identification, quantitation, and purification of cockroach allergens using monoclonal antibodies. s. pollart, d. mullins, + authors m. chapman medicine the journal of allergy and clinical immunology save alert research feed proteome mining for novel ige‐binding proteins from the german cockroach (blattella germanica) and allergen profiling of patients jiing-guang chuang, song-nan su, b. chiang, how-jing lee, l. chow biology, medicine proteomics save alert research feed ... ... related papers abstract topics citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue durham research online deposited in dro: may version of attached �le: accepted version peer-review status of attached �le: peer-reviewed citation for published item: grinfeld, michael and volkov, stanislav and wade, andrew r. ( ) 'convergence in a multidimensional randomized keynesian beauty contest.', advances in applied probability., ( ). pp. - . further information on publisher's website: http://dx.doi.org/ . /aap/ publisher's copyright statement: additional information: use policy the full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro�t purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in dro • the full-text is not changed in any way the full-text must not be sold in any format or medium without the formal permission of the copyright holders. please consult the full dro policy for further details. durham university library, stockton road, durham dh ly, united kingdom tel : + ( ) | fax : + ( ) https://dro.dur.ac.uk https://www.dur.ac.uk http://dx.doi.org/ . /aap/ http://dro.dur.ac.uk/ / https://dro.dur.ac.uk/policies/usepolicy.pdf https://dro.dur.ac.uk applied probability trust ( th march ) convergence in a multidimensional randomized keynesian beauty contest michael grinfeld,∗ university of strathclyde stanislav volkov,∗∗ lund university and university of bristol andrew r. wade,∗∗∗ durham university abstract we study the asymptotics of a markovian system of n ≥ particles in [ , ]d in which, at each step in discrete time, the particle farthest from the current centre of mass is removed and replaced by an independent u[ , ]d random particle. we show that the limiting configuration contains n − coincident particles at a random location ξn ∈ [ , ] d. a key tool in the analysis is a lyapunov function based on the squared radius of gyration (sum of squared distances) of the points. for d = we give additional results on the distribution of the limit ξn, showing, among other things, that it gives positive probability to any nonempty interval subset of [ , ], and giving a reasonably explicit description in the smallest nontrivial case, n = . keywords: keynesian beauty contest; radius of gyration; rank-driven process; sum of squared distances. mathematics subject classification: primary j secondary d ; f ; k ; c ; a . introduction, model, and results in a keynesian beauty contest, n players each guess a number, the winner being the player whose guess is closest to the mean of all the n guesses; the name marks keynes’s discussion of “those newspaper competitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average preferences of the competitors as a whole” [ , ch. , §v]. moulin [ , p. ] formalized a version of the game played on a real interval, the “p-beauty contest”, in which the target is p (p > ) times the mean value. see e.g. [ ] and references therein for some recent work on game-theoretic aspects of such “contests” in economics. in this paper we study a stochastic process based on an iterated version of the game, in which players randomly choose a value in [ , ], and at each step the worst performer ∗ postal address: department of mathematics and statistics, university of strathclyde, richmond street, glasgow g xh, uk. ∗∗ postal address: centre for mathematical sciences, lund university, box se- , lund, sweden, and department of mathematics, university of bristol, university walk, bristol bs tw, uk. ∗∗∗ postal address: department of mathematical sciences, durham university, south road, durham dh le, uk. michael grinfeld, stanislav volkov, andrew r. wade (that is, the player whose guess is farthest from the mean) is replaced by a new player; each player’s guess is fixed as soon as they enter the game, so a single new random value enters the system at each step. analysis of this model was posed as an open problem in [ , p. ]. the natural setting for our techniques is in fact a generalization in which the values live in [ , ]d and the target is the barycentre (centre of mass) of the values. we now formally describe the model and state our main results. let d ∈ n := { , , . . .}. we use the notation xn = (x , x , . . . , xn) for a vector of n points xi ∈ r d. we write µn(xn) := n − ∑n i= xi for the barycentre of xn, and ‖ · ‖ for the euclidean norm on rd. let ord(xn) = (x( ), x( ), . . . , x(n)) denote the barycentric order statistics of x , . . . , xn, so that ‖x( ) − µn(xn)‖ ≤ ‖x( ) − µn(xn)‖ ≤ · · · ≤ ‖x(n) − µn(xn)‖; any ties are broken randomly. we call x ∗ n := x(n) the extreme point of xn, a point of x , . . . , xn farthest from the barycentre. we define the core of xn as x ′n := (x( ), . . . , x(n− )), the vector of x , . . . , xn with the extreme point removed. the markovian model that we study is defined as follows. fix n ≥ . start with x ( ), . . . , xn( ), distinct points in [ , ] d, and write xn ( ) := (x( )( ), . . . , x(n)( )) for the corresponding ordered vector. one possibility is to start with a uniform random initial configuration, by taking x ( ), . . . , xn( ) to be independent u[ , ] d random variables; here and elsewhere u[ , ]d denotes the uniform distribution on [ , ]d. in this uniform random initialization, all n points are indeed distinct with probability . given xn(t), replace x ∗ n(t) = x(n)(t) by an independent u[ , ] d random variable ut+ , so that xn (t + ) = ord(x( )(t), . . . , x(n− )(t), ut+ ). the interesting case is when n ≥ : the case n = is trivial, and the case n = is also uninteresting since at each step either point is replaced with probability / by a u[ , ] variable, so that, regardless of the initial configuration, after a finite number of steps we will have two independent u[ , ] points. our main result, theorem . , shows that for n ≥ all but the most extreme point of the configuration converge to a common limit. theorem . . let d ∈ n and n ≥ . let xn( ) consist of n distinct points in [ , ] d. there exists a random ξn := ξn (xn( )) ∈ [ , ] d such that x ′n(t) a.s. −→ (ξn , ξn, . . . , ξn ), and x ∗ n(t) − ut a.s. −→ , ( . ) as t → ∞. in particular, for u ∼ u[ , ]d, as t → ∞, xn(t) d −→ (ξn, ξn, . . . , ξn, u). remark . . under the conditions of theorem . , despite the fact that x ∗n (t)−ut → a.s., we will see below that x ∗n (t) = ut infinitely often a.s. theorem . is proved in section . then, section is devoted to the one-dimensional case, where we obtain various additional results on the limit ξn. finally, the appen- dices, a and b, collect some results on uniform spacings and continuity of distributional fixed-points that we use in parts of the analysis in section . . proof of convergence intuitively, the evolution of the process is as follows. if, on replacement of the extreme point, the new point is the next extreme point (measured with respect to the randomized keynesian beauty contest new centre of mass), then the core is unchanged. however, if the new point is not extreme, it typically penetrates the core significantly, while a more extreme point is thrown out of the core, reducing the size of the core in some sense (we give a precise statement below). tracking the evolution of the core, by following its centre of mass, one sees increasingly long periods of inactivity, since as the size of the core decreases changes occur less often, and moreover the magnitude of the changes decreases in step with the size of the core. the dynamics are nontrivial, but bear some resemblance to random walks with decreasing steps (see e.g. [ , ] and references therein) as well as processes with reinforcement such as the pólya urn (see e.g. [ ] for a survey). the process is also reminiscent in some ways of iterated interval division [ ] or sequential adsorption with interaction [ ]. our analysis will rest on a ‘lyapunov function’ for the process, that is, a function of the configuration that possesses pertinent asymptotic properties. one may initially hope, for example, that the diameter of the point set xn(t) would decrease over time, but this cannot be the case because the newly added point can be anywhere in [ , ]d. what then about the diameter of x ′n(t), for which the extreme point is ignored? we will show later in this section that this quantity is in fact well behaved, but we have to argue somewhat indirectly: the diameter of x ′n(t) can increase (at least for n big enough; see remark . below). however, there is a monotone decreasing function associated with the process, based on the sum of squared distances of a configuration, which we will use as our lyapunov function. to define this function (see ( . ) below) we need some notation. for n ∈ n and xn = (x , x , . . . , xn) ∈ (r d)n, write gn(xn) := gn(x , . . . , xn) := n − n ∑ i= i− ∑ j= ‖xi − xj‖ = n ∑ i= ‖xi − µn(xn)‖ ; ( . ) a detailed proof of the (elementary) final equality in ( . ) may be found on pp. – of [ ], for example. we remark that n gn is the squared radius of gyration of x , . . . , xn: see e.g. [ ], p. . note also that calculus verifies the useful variational formula gn(x , . . . , xn) = inf y∈rd n ∑ i= ‖xi − y‖ . ( . ) for n ≥ , define fn(xn) := fn(x , . . . , xn) := gn− (x ′ n) = gn− (x( ), . . . , x(n− )). lemma . . let n ≥ and xn = (x , x , . . . , xn) ∈ (r d)n. then for any x ∈ rd, fn(x( ), . . . , x(n− ), x) ≤ fn(xn). proof. for ease of notation, we write simply (x , . . . , xn) for (x( ), . . . , x(n)), i.e., we relabel so that xj is the jth closest point to µn(xn). then x ∗ n = xn, x ′ n = (x , . . . , xn− ), and fold := fn(xn) = gn− (x , . . . , xn− ) = n− ∑ i= ‖xi − µ ′ old‖ , ( . ) michael grinfeld, stanislav volkov, andrew r. wade where µ′old := µn− (x ′ n). we compare fold to fn evaluated on the set of points obtained by removing xn and replacing it with some x ∈ r d. write y := {x , . . . , xn− , x} ∗ for the new extreme point. then fnew := fn(x , . . . , xn− , x) = n− ∑ i= ‖xi − µ ′ new‖ + ‖x − µ′new‖ − ‖y − µ′new‖ , ( . ) where µ′new := n − ( n− ∑ i= xi + x − y ) = µ′old + x − y n − . ( . ) denote µnew := µn(x , . . . , xn− , x), so µ′new = nµnew n − − y n − . ( . ) from ( . ), ( . ), and ( . ), we obtain fnew − fold = n− ∑ i= ( ‖xi − µ ′ new‖ − ‖xi − µ ′ old‖ ) + ‖x − µ′new‖ − ‖y − µ′new‖ . ( . ) for the sum on the right-hand side of ( . ), we have that n− ∑ i= ( ‖xi − µ ′ new‖ − ‖xi − µ ′ old‖ ) = n− ∑ i= ( xi · (µ ′ old − µ ′ new) + ‖µ ′ new‖ − ‖µ′old‖ ) = (n − ) ( µ′old · (µ ′ old − µ ′ new) + ‖µ ′ new‖ − ‖µ′old‖ ) = (n − ) ( ‖µ′old‖ − (µ′old · µ ′ new) + ‖µ ′ new‖ ) . simplifying this last expression and substituting back into ( . ) gives fnew − fold = (n − )‖µ′old − µ ′ new‖ + ‖x − µ′new‖ − ‖y − µ′new‖ . thus, using ( . ) and then ( . ), fnew − fold = ‖x − y‖ n − + ‖x‖ − ‖y‖ − µ′new · (x − y) = ‖x‖ + ‖y‖ − x · y n − + ‖x‖ − ‖y‖ − ( nµnew n − − y n − ) · (x − y). hence we conclude that fnew − fold = n n − ( ‖x‖ − ‖y‖ − µnew · (x − y) ) = n n − ( ‖x − µnew‖ − ‖y − µnew‖ ) ≤ , ( . ) since y is, by definition, the farthest point from µnew. now we return to the stochastic model. define f(t) := fn(xn (t)). ( . ) lemma . has the following immediate consequence. randomized keynesian beauty contest corollary . . let n ≥ . then f(t + ) ≤ f(t). corollary . shows that our lyapunov function f(t) is nonincreasing; later we show that f(t) → a.s. (see lemma . below). first, we need to relate f(t) to the diameter of the point set x ′n(t). for n ≥ and x , . . . , xn ∈ r d, write dn(x , . . . , xn) := max ≤i,j≤n ‖xi − xj‖. lemma . . let n ≥ and x , . . . , xn ∈ r d. then dn(x , . . . , xn) ≤ gn(x , . . . , xn) ≤ (n − )dn(x , . . . , xn) . remark . . the lower bound in lemma . is sharp, and is attained by collinear configurations with two diametrically opposed points xi, xj and all the other n− points at the midpoint µ (xi, xj) = µn(x , . . . , xn). the upper bound in lemma . is not, in general, sharp; determining the sharp upper bound is a nontrivial problem. the bound gn(x , . . . , xn) ≤ n ( d d+ ) dn(x , . . . , xn) from [ ] is also not always sharp. witsenhausen [ ] conjectured that the maximum is attained if and only if the points are distributed as evenly as possible among the vertices of a regular d-dimensional simplex of edge-length dn(x , . . . , xn); this was proved relatively recently [ , ]. proof of lemma . . fix x , . . . , xn ∈ r d. for ease of notation, write µ = µn(x , . . . , xn). first we prove the lower bound. for n ≥ , using the second form of gn in ( . ), gn(x , . . . , xn) = n ∑ i= ‖xi − µ‖ ≥ ‖xi − µ‖ + ‖xj − µ‖ , for (xi, xj) a diameter, i.e., dn(x , . . . , xn) = ‖xi − xj‖. by the n = case of ( . ), ‖xi − µ‖ + ‖xj − µ‖ ≥ ‖xi − µ (xi, xj)‖ = ‖xi − xj‖ . this gives the lower bound. for the upper bound, from the first form of gn in ( . ), gn(x , . . . , xn) ≤ n n ∑ i= (i − )dn(x , . . . , xn) , by the definition of dn, which yields the result. let d(t) := dn− (x ′ n (t)). remark . . by lemma . (or ( . )), g (x ′ (t)) = d (x ′ (t)) , so when n = , lemma . implies that d(t + ) ≤ d(t) a.s. as well. if d = , it can be shown that d(t) is nonincreasing also when n = . in general, however, d(t) can increase. let ft := σ(xn ( ), xn( ), . . . , xn(t)), the σ-algebra generated by the process up to time t. let b(x; r) denote the closed euclidean d-ball with centre x ∈ rd and radius r > . define the events at+ := {ut+ ∈ b(µn− (x ′ n (t)); d(t))}, a ′ t+ := {ut+ ∈ b(µn− (x ′ n (t)); d(t)/ )}. michael grinfeld, stanislav volkov, andrew r. wade lemma . . there is an absolute constant γ > for which, for all n ≥ and all t, a′t+ ⊆ {f(t + ) − f(t) ≤ −γn − f(t)} ⊆ {f(t + ) − f(t) < } ⊆ at+ . ( . ) moreover, there exist constants c > and c < ∞, depending only on d, for which, for all n ≥ and all t, a.s., p [ f(t + ) − f(t) ≤ −γn− f(t) | ft ] ≥ p[a′t+ | ft] ≥ cn −d/ (f(t))d/ ; ( . ) p [f(t + ) − f(t) < | ft] ≤ p[at+ | ft] ≤ c(f(t)) d/ . ( . ) proof. for simplicity we write x , . . . , xn− instead of x( )(t), . . . , x(n− )(t) and d instead of d(t) = dn− (x , . . . , xn− ). by definition of d, there exists some i ∈ { , . . . , n − } such that ‖µ′old − xi‖ ≥ d/ , where µ ′ old = µn− (x , . . . , xn− ). given ft, the event a ′ t+ , that the new point u := ut+ falls in b(µ ′ old; d/ ), has probability bounded below by θdd d, where θd > depends only on d. let µnew := µn(x , . . . , xn− , u). suppose that a ′ t+ occurs. then, ‖µnew − µ ′ old‖ = n ‖u − µ′old‖ ≤ d n ≤ d , ( . ) since n ≥ . hence, by ( . ) and the triangle inequality, ‖u − µnew‖ ≤ ‖u − µ ′ old‖ + ‖µnew − µ ′ old‖ ≤ d + d = d . ( . ) on the other hand, by another application of the triangle inequality and ( . ), ‖µnew − xi‖ ≥ ‖µ ′ old − xi‖ − ‖µnew − µ ′ old‖ ≥ d − d = d . then, by definition, the extreme point y := {x , . . . , xn− , u} ∗ satisfies ‖y − µnew‖ ≥ ‖µnew − xi‖ ≥ d . ( . ) hence from the x = u case of ( . ) with the bounds ( . ) and ( . ), we conclude f(t + ) − f(t) ≤ n n − ( ( d ) − ( d ) ) (a′t+ ) ≤ − d (a′t+ ), ( . ) for all n ≥ ; the first inclusion in ( . ) follows (with γ = / ) from ( . ) together with the fact that, by the second inequality in lemma . , d ≥ n− f(t). this in turn implies ( . ), using the fact that p[a′t+ | ft] ≥ θdd d. next we consider the event at+ . using the same notation as above, we have that ‖µnew − u‖ ≥ ‖µ ′ old − u‖ − ‖µnew − µ ′ old‖ = ( − n ) ‖µ′old − u‖, by the equality in ( . ). also, for any k ∈ { , . . . , n − }, ‖µnew − xk‖ ≤ ‖µ ′ old − xk‖ + ‖µ ′ old − µnew‖ ≤ d + n ‖µ′old − u‖, randomized keynesian beauty contest by ( . ) again. combining these estimates we obtain, for any k ∈ { , . . . , n − }, ‖µnew − u‖ − ‖µnew − xk‖ ≥ ( − n ) ‖µ′old − u‖ − d ≥ ‖µ′old − u‖ − d, for n ≥ . so in particular, ‖µnew − u‖ > ‖µnew − xk‖ for all k ∈ { , . . . , n − } provided ‖µ′old − u‖ > d, i.e., u /∈ b(µ ′ old; d). in this case, u is the extreme point among u, x , . . . , xn− , i.e., act+ ⊆ {x ∗ n(t + ) = ut+ }. ( . ) in particular, on act+ , f(t + ) = f(t), and f(t + ) < f(t) only if at+ occurs, giving the final inclusion in ( . ). since p[at+ | ft] is bounded above by cdd d for a constant cd < ∞ depending only on d, ( . ) follows from the first inequality in lemma . . this completes the proof. lemma . . suppose that n ≥ . then, as t → ∞, f(t) → a.s. and in l . proof. let ε > and let σ := min{t ∈ z+ : f(t) ≤ ε}, where z+ := { , , , . . .}. then by ( . ), there exists δ > (depending on d, ε, and n) such that, a.s., p [f(t + ) − f(t) ≤ −δ | ft] ≥ δ {t < σ}. hence, since f(t + ) − f(t) ≤ a.s. by corollary . , e [f(t + ) − f(t) | ft] ≤ −δ {t < σ}. ( . ) by corollary . , f(t) is nonnegative and nonincreasing, and hence f(t) converges a.s. as t → ∞ to some nonnegative limit f(∞); the convergence also holds in l since f(t) is uniformly bounded. in particular, e[f(t)] → e[f(∞)]. so taking expectations in ( . ) and letting t → ∞ we obtain lim sup t→∞ δ p[σ > t] ≤ , which implies that p[σ > t] → as t → ∞. thus σ < ∞ a.s., which together with the monotonicity of f(t) (corollary . ) implies that f(t) ≤ ε for all t sufficiently large. since ε > was arbitrary, the result follows. recall the definition of at and a ′ t from before lemma . . define (ft) stopping times τ := and, for n ∈ n, τn := min{t > τn− : at occurs}. then f(t) < f(t − ) can only occur if t = τn for some n. since p[at+ | ft] is bounded below by cf(t) d/ for some c > , it is not hard to see that, provided f( ) > , at occurs infinitely often, a.s. indeed, suppose that f( ) > and at occurs only finitely often. then f(t) has a non-zero limit. on the other hand, ∑ t cf(t) d/ ≤ ∑ t p[at+ | ft] < ∞, by lévy’s extension of the borel–cantelli lemma, so that f(t) → a.s., which is a contradiction. hence τn < ∞, a.s., for all n. lemma . . let n ≥ . there exists α > such that, a.s., d(τn) ≤ e −αn for all n sufficiently large. michael grinfeld, stanislav volkov, andrew r. wade proof. we have from ( . ) and the second inequality in lemma . that f(τn) − f(τn − ) ≤ −δf(τn − ) (a ′ τn ), for some δ > . note also that, by definition of the stopping times τn, f(τn − ) = f(τn− ). hence, p[f(τn) − f(τn− ) ≤ −δf(τn− ) | fτn− ] ≥ p[a ′ τn | fτn− ] ≥ δ, taking δ > small enough, since, using the fact that (aτn) = a.s., p[a′τn | fτn− ] = e [ p[a′τn | fτn] (aτn) | fτn− ] = e [ p[a′τn | aτn] | fτn− ] , where by definition of at and a ′ t, p[a ′ τn | aτn] is uniformly positive. since f(t + ) − f(t) ≤ a.s. (by corollary . ) it follows that e [ f(τn) − f(τn− ) | fτn− ] ≤ −δ f(τn− ). taking expectations, we obtain e[f(τn)] ≤ ( − δ )e[f(τn− )], which implies that e[f(τn)] = o(e −cn), for some c > depending on δ. then by markov’s inequality, p[f(τn) ≥ e −cn/ ] = o(e−cn/ ), which implies that f(τn) = o(e −cn/ ), a.s., by the borel–cantelli lemma. then the first inequality in lemma . gives the result. remark . . the proof of lemma . shows that p[a′τn | fτn− ] is uniformly positive, so lévy’s version of the borel–cantelli lemma, with the fact that τn < ∞ a.s. for all n, shows that a′t occurs for infinitely many t, a.s. with the proof of lemma . , this shows that x ∗n(t) = ut infinitely often, as claimed in remark . . we are almost ready to complete the proof of theorem . . we state the main step in the remaining argument as the first part of the the next lemma, while the second part of the lemma we will need in section . below. for ε > , define the stopping time νε := min{t ∈ n : f(t) < ε }; for any ε > , νε < ∞ a.s., by lemma . . lemma . . let n ≥ . then there exists ξn ∈ [ , ] d such that µn− (x ′ n (t)) → ξn a.s. and in l as t → ∞. moreover, there exists an absolute constant c such that for any ε > , and any t ∈ n, on {νε ≤ t }, a.s., e [ max t≥t ‖µn− (x ′ n (t)) − µn− (x ′ n (t ))‖ | ft ] ≤ cε. proof. let µ′(t) := µn− (x ′ n (t)). observe that for n ≥ , x ′ n (t) and x ′ n(t − ) have at least one point in common; choose one such point, and call it z(t). then µ′(t) ∈ hull x ′n(t) ⊆ hull xn(t), where hull x denotes the convex hull of the point set x . so ‖z(t) − µ′(t)‖ ≤ d(t). similarly ‖z(t) − µ′(t − )‖ ≤ d(t − ). by definition of τn, µ ′(t) = µ′(t − ) and d(t) = d(t − ) unless t = τn for some n, in which case µ′(τn − ) = µ ′(τn− ) and d(τn − ) = d(τn− ). hence, ∑ t≥ ‖µ′(t) − µ′(t − )‖ = ∑ n≥ ‖µ′(τn) − µ ′(τn− )‖ ≤ ∑ n≥ (‖µ′(τn) − z(τn)‖ + ‖µ ′(τn− ) − z(τn)‖) , ( . ) randomized keynesian beauty contest by the triangle inequality. then the preceding remarks imply that ∑ t≥ ‖µ′(t) − µ′(t − )‖ ≤ ∑ n≥ (d(τn) + d(τn− )) < ∞, a.s., by lemma . . hence there is some (random) ξn ∈ [ , ] d for which µ′(t) → ξn a.s. as t → ∞, and l convergence follows by the bounded convergence theorem. for the final statement in the lemma we use a variation of the preceding argument. let m := max{n ∈ z+ : τn ≤ t }. then f(t ) = f(τm ) and µ ′(τm ) = µ ′(t ), so that on {νε ≤ t }, we have {νε ≤ τm } as well. hence (by corollary . ) f(τm ) < ε . a similar argument to that in the proof of lemma . shows that, for m ≥ , e[f(τm+m) | ft ] ≤ e −cm e[f(τm ) | ft ] ≤ ε e−cm, on {νε ≤ t }, where c > depends on n but not on m or ε. thus by lemma . , on {νε ≤ t }, e[d(τm+m) | ft ] ≤ ε e−cm. also, similarly to ( . ), max t≥τm ‖µ′(t) − µ′(τm )‖ ≤ ∑ t≥τm ‖µ′(t) − µ′(t − )‖ ≤ ∑ m≥ (d(τm+m) + d(τm+m− )) . taking expectations and using the cauchy–schwarz inequality, we obtain, on {νε ≤ t }, e [ max t≥t ‖µ′(t) − µ′(t )‖ | ft ] = e [ max t≥τm ‖µ′(t) − µ′(τm )‖ | ft ] ≤ ε ec ∑ m≥ e−cm, a constant times ε . jensen’s inequality now gives the result, with c = −e−c . proof of theorem . . again let µ′(t) := µn− (x ′ n(t)). we have from lemma . that µ′(t) → ξn a.s. now, for any j ∈ { , . . . , n − }, by the triangle inequality, ‖x(j)(t) − ξn ‖ ≤ ‖x(j)(t) − µ ′(t)‖ + ‖µ′(t) − ξn‖ ≤ d(t) + ‖µ ′(t) − ξn‖, which tends to a.s. as t → ∞, since d(t) → a.s. by lemma . . this establishes the first statement in ( . ). moreover, by ( . ), x ∗n(t+ ) = ut+ only if at+ occurs. on at+ , x ∗ n(t + ) is one of the points of x ′ n(t), and so ‖x ∗ n(t + ) − µ ′(t)‖ ≤ d(t). in addition, on at+ , we have ‖ut+ − µ ′(t)‖ ≤ d(t). so by the triangle inequality, ‖x ∗n(t + ) − ut+ ‖ ≤ d(t) (at+ ), which tends to a.s., again by lemma . . this gives the final part of ( . ). . the limit distribution in one dimension . . overview and simulations throughout this section we restrict attention to d = . of interest is the distribution of the limit ξn in ( . ), and its behaviour as n → ∞. simulations suggest that ξn is highly dependent on the initial configuration: figure shows histogram estimates for ξn from repeated simulations with a deterministic initial condition. in more detail, michael grinfeld, stanislav volkov, andrew r. wade runs of each simulation were performed, each starting from the same initial condition; each run was terminated when d(t) < . for the first time, and the value of µn− (x ′ n(t)) was output as an approximation to ξn (cf theorem . ). note that, by ( . ), in the simulations one may take the new points not u[ , ] but uniform on a typically much smaller interval, which greatly increases the rate of updates to the core configuration. . . . . . . . . . . . . figure : normalized histograms each based on simulations, with n = and initial points , , (left) and n = and initial points k , k ∈ { , . . . , } (right). figure shows sample results obtained with an initial condition of n i.i.d. u[ , ] random points. now the histograms appear much simpler, although, of course, they can be viewed as mixtures of complicated multi-modal histograms similar to those in figure . in the uniform case, it is natural to ask whether ξn converge in distribution to some limit distribution as n → ∞. the form of the histograms in figure might suggest a beta distribution (this is one sense in which the randomized beauty contest is “reminiscent of a pólya urn” [ , p. ]). an ad-hoc kolmogorov–smirnov analysis (see table . ) suggests that the distributions are indeed ‘close’ to beta distributions, but different enough for the match to be unconvincing. simulations for large n are computationally intensive. we remark that it is not unusual for beta or ‘approximate beta’ distributions to appear as limits of schemes that proceed via iterated procedures on intervals: see for instance [ ] and references therein. n β κ(β) . . . . . . . . table : κ(β) is the kolmogorov–smirnov distance between a beta(β, β) distribution and the empirical distribution from the samples of size plotted in figure , minimized over β in each case. randomized keynesian beauty contest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . figure : normalized histograms for simulations with random i.i.d. uniform initial conditions, with (top row) n = , and (bottom row) n = , . in the rest of this section we study ξn and its distribution. our results on the limit distribution, in particular, leave several interesting open problems, including a precise description of the phenomena displayed by the simulations reported above. in section . we give an alternative (one might say ‘phenomenological’) characterization of the limit ξn , and contrast this with an appropriate rank-driven process in the sense of [ ]. in section . we show that the distribution of ξn is fully supported on ( , ) and assigns positive probability to any proper interval, using a construction permitting transformations of configurations. finally, section . is devoted to the case n = , for which some explicit computations for the distribution of ξn (in particular, its moments) are carried out. . . a characterization of the limit let πn(t) := t # {s ∈ { , , . . . , t} : x ∗n(s) < µn(xn(s))} , michael grinfeld, stanislav volkov, andrew r. wade the proportion of times up to time t for which the extreme point was the leftmost point (as opposed to the rightmost). the next result shows that πn (t) converges to the (random) limit ξn given by theorem . ; we give the proof after some additional remarks. proposition . . let d = and n ≥ . then limt→∞ πn (t) = ξn a.s. it is instructive to contrast this behaviour with a suitable rank-driven process (cf [ ]). namely, fix a parameter π ∈ ( , ). take n points in [ , ], and at each step in discrete time replace either the leftmost point (with probability π) or else the rightmost point (probability −π), independently at each step; inserted points are independent u[ , ] variables. for this process, results of [ ] show that the marginal distribution of a typical point converges (as t → ∞ and then n → ∞) to a unit point mass at π (cf remark . in [ ]). this leads us to one sense in which the randomized beauty contest is, to a limited extent, “reminiscent of a pólya urn” [ , p. ]. recall that a pólya urn consists of an increasing number of balls, each of which is either red or blue; at each step in discrete time, a ball is drawn uniformly at random from the urn and put back into the urn together with an extra ball of the same colour. the stochastic process of interest is the proportion of red balls, say; it converges to a random limit π′, which has a beta distribution. the beauty contest can be viewed as occupying a similar relation to the rank-driven process described above as the pólya urn process does to the simpler model in which, at each step, independently, either a red ball is added to the urn (with probability π′) or else a blue ball is added (probability − π′). proof of proposition . . given τ , τ , τ , . . ., ξn = limn→∞ µn− (x ′ n(τn)) is in- dependent of ut, t /∈ {τ , τ , . . .}, since, by ( . ), any such ut is replaced at time t + . let ε > . by theorem . , there exists a random t < ∞ a.s. for which max ≤i≤n− |ξn − x(i)(t)| ≤ ε for all t ≥ t . since µn(xn(t + )) = n− n µn− (x ′ n(t)) + n ut+ , we have that for t ≥ t , using the triangle inequality, for any i ∈ { , . . . , n − }, |µn(xn (t + )) − x(i)(t)| ≤ ε + |µn(xn(t + )) − ξn| ≤ ε + n − n |µn− (x ′ n(t)) − ξn | + n |ut+ − ξn |. hence, for t ≥ t , max ≤i≤n− ∣ ∣x(i)(t) − µn(xn(t + )) ∣ ∣ ≤ n |ξn − ut+ | + ε. ( . ) on the other hand, for t ≥ t , µn(xn (t + )) ≥ n− n (ξn − ε) + n ut+ , so that for i ∈ { , . . . , n − }, µn(xn (t + )) − ut+ ≥ n − n (ξn − ut+ − ε). ( . ) randomized keynesian beauty contest suppose that ut+ < ξn − kε for some k ∈ ( , ∞). then, from ( . ) and ( . ), |µn(xn (t + )) − ut+ | − max ≤i≤n− ∣ ∣x(i)(t) − µn(xn(t + )) ∣ ∣ ≥ n − n (ξn − ut+ ) − n − n ε > ε n ((n − )k − n + ) . this last expression is positive provided k ≥ n− n− , which is the case for all n ≥ with the choice k = , say. hence, with this choice of k, {ut+ < ξn − ε} implies that ut+ is farther from µn+ (xn(t + )) than is any of the points left over from x ′n(t). write lt := {ut < ξn − ε}. then we have shown that, for t ≥ t , the event lt implies that ut = x ∗ n(t), and, moreover, ut < µn(xn (t)). hence, for t ≥ t , πn(t) ≥ t t ∑ s=t (ls) ≥ t t ∑ s=t s/∈{τ ,τ ,...} (ls). given τ , τ , . . ., us, s /∈ {τ , τ , . . .} are independent of t and ξn. for such an s, us is uniform on is := [ , ] \ b(µn− (x ′ n (s)); d(s)), and, for s ≥ t , d(s) ≤ ε so that is ⊇ [ , max{ξn − ε, }] ∪ [min{ξn + ε, }, ]. hence, given s /∈ {τ , τ , . . .} and s ≥ t , p[ls] = p[us < ξn − ε | us ∈ is] ≥ ξn − ε. hence, considering separately the cases ξn > ε and ξn ≤ ε, the strong law of large numbers implies that t t ∑ s=t s/∈{τ ,τ ,...} (ls) ≥ ξn − ε, for all t sufficiently large; here we have used the fact that t − t → ∞ a.s. as t → ∞ and #{n ∈ z+ : τn ≤ t} = o(t) a.s., which follows from ( . ) and lemma . with a standard concentration argument using e.g. the azuma–hoeffding inequality. since ε > was arbitrary, it follows that lim inft→∞ t − πn(t) ≥ ξn a.s. the sym- metrical argument considering events of the form rt := {ut > ξn + ε} shows that lim inft→∞( − t − πn(t)) ≥ − ξn a.s., so lim supt→∞ t − πn(t) ≤ ξn a.s. combining the two bounds gives the result. . . the limit has full support in this section, we prove that ξn is fully supported on ( , ) in the sense that ess inf ξn = , ess sup ξn = , and ξn assigns positive probability to any non-null interval. let mn( ) := min{‖xi( ) − xj( )‖ : i, j ∈ { , , . . . , n + }, i = j}, ( . ) where we use the conventions x ( ) := and xn+ ( ) := . for ρ > let sρ denote the f -event sρ := {mn( ) ≥ ρ} that no point of xn( ) is closer than distance ρ to any other point of xn( ) or to either of the ends of the unit interval. michael grinfeld, stanislav volkov, andrew r. wade proposition . . let d = and n ≥ . let ρ ∈ ( , ). for any non-null interval subset i of [ , ], there exists δ > (depending on n, i, and ρ) for which p[ξn ∈ i | xn( )] ≥ δ (sρ), a.s. ( . ) in particular, in the case where xn( ) consists of n independent u[ , ] points, p[ξn ∈ i] > for any non-null interval i ⊆ [ , ]. we suspect, but have not been able to prove, that ξn has a density fn with respect to lebesgue measure, i.e., ξn is absolutely continuous in the sense that for every ε > there exists δ > such that p[ξn ∈ a] < ε for every a with lebesgue measure less than δ. note that p[ξn ∈ a | xn( )] may be if xn( ) contains non-distinct points: e.g. if n ≥ and xn( ) = (x, x, . . . , x, y), then x ′ n(t) = (x, x, . . . , x) for all t. for a ∈ [ , ], ε > , and t ∈ n, define the event ea,ε(t) := n ⋂ i= {|xi(t) − a| < ε} . the main new ingredient needed to obtain proposition . is the following result. lemma . . let n ≥ . for any ρ ∈ ( , ) and ε > there exist t ∈ n and δ > (depending on n, ρ, and ε) for which, for all a ∈ [ , ], p[ea,ε(t ) | xn( )] > δ (sρ), a.s. proof. fix a ∈ [ , ]. let ρ ∈ ( , ) and ε > . it suffices to suppose that ε ∈ ( , ρ), since ea,ε(t) ⊆ ea,ε′(t) for ε ′ ≥ ε. suppose that sρ occurs, so that mn( ) ≥ ρ with mn( ) defined at ( . ). for ease of notation we list the points of xn ( ) in increasing order as < x < x < · · · < xn < . let m = ⌊n/ ⌋. let ν = ε/n . the following argument shows how one can arrive at a configuration at a finite (deterministic) time t where all of x (t ), . . . , xn(t ) lie inside (a−ε, a+ε) with a positive (though possibly very small) probability. let us call the points which are present at time old points; the points which will gradually replace this set will be called new points. we will first describe an event by which all the old points are removed and replaced by new points arranged approximately equidistantly in the interval [xm, xm+ ], and then we will describe an event by which such a configuration can migrate to the target interval. step . starting from time , iterate the following procedure until a new point becomes an extreme point. the construction is such that at each step, the extreme point is one of the old points, either at the extreme left or right of the configuration. at each step, the extreme old point is removed and replaced by a new u[ , ] point to form the configuration at the next time unit. we describe an event of positive probability by requiring the successive new arrivals to fall in particular intervals, as follows. the first old point removed from the right is replaced by a new point in (xm + ν, xm + ν + δ), where δ ∈ ( , ν) will be specified later. subsequently, the ith point (i ≥ ) removed from the right is replaced by a new point in (xm +iν, xm +iν +δ). we call this subset of new points the accumulation on the left. on the other hand, the ith extreme point removed from the left (i ∈ n) is replaced by a new point in (xm+ −iν, xm+ −iν +δ). this second subset of new points will be called the accumulation on the right. randomized keynesian beauty contest during the first m steps of this procedure, the new points are necessarily internal points of the configuration and so are never removed. therefore, there will be a time t ∈ [m, n] at which, for the first time, one of the new points becomes either the leftmost or rightmost point of xn(t ); suppose that it is the rightmost, since the argument in the other case is analogous. if at time t the accumulation on the right is non-empty, we continue to perform the procedure described in step , but now allowing ourselves to remove new points from the accumulation on the right. so we continue putting extra points on the accumulation on the left whenever the rightmost point is removed, and similarly putting extra points to the accumulation on the right whenever the leftmost point is removed, as described for step . eventually we will have either (a) a configuration where all the new points of the left or the right accumulation are completely removed, and there are still some of the old points left, or (b) a configuration where all old points are removed. the next step we describe separately for these two possibilities. step (a). without loss of generality, suppose that the accumulation on the right is empty, so the configuration consists of k points of the left accumulation and n − k old points remaining to the left of xm (including xm itself). note that step produces at least m new points, so m ≤ k ≤ n − , since by assumption we have at least one old point remaining. let us now denote the points of the configuration x < x < · · · < xn so that xn−k = xm, and by the construction in step , xn−k+i ∈ (xm + iν, xm + iν + δ) for i = , , . . . , k. provided that k ≤ n − , so that there are at least old points, we will show that x is necessarily the extreme point of the configuration. indeed, writing µ = µn(x , . . . , xn), using the fact that xn−k+i ≥ xn−k + iν for ≤ i ≤ k and xn ≤ xn−k + kν + δ, we have µ − x + xn ≥ x + · · · + xn−k + kxn−k + νk(k + ) n − x + xn−k + νk + δ = n ( x + · · · + xn−k + ( k − n)xn−k − nx + νk(k + − n) − δn) . the old points all have separation at least ρ, so for ≤ i ≤ n − k, xi ≥ x + (i − )ρ, and hence x +· · ·+ xn−k +( k−n)xn−k ≥ nx +ρ(n −k− )(n −k)+ρ( k−n)(n −k− ). it follows, after simplification, that µ − x + xn ≥ n (k(n − k − )(ρ − ν) − δn) ≥ n ((n − )(ρ − ν) − δn) , provided ≤ k ≤ n − . by choice of ν, we have ν ≤ ρ/ and it follows that the last displayed expression is positive provided δ is small enough compared to ρ (δ < ρ/ , say). hence |x −µ| > |xn −µ|. thus next we remove x . we replace it similarly to the procedure in step , but now building up the accumulation on the left. we can thus iterate this step, removing old points from the left and building up the accumulation on the left, while keeping the accumulation on the right empty, until we get just one old point remaining (i.e. until k = n − ); this last old point will be xm . at this stage, michael grinfeld, stanislav volkov, andrew r. wade after a finite number of steps, we end up with a configuration where the set of points x < x < · · · < xn satisfies xi ∈ [xm + (i − )ν, xm + (i − )ν + δ], i = , , . . . , n. step (b). suppose that the configuration is such that all old points have been removed but both left and right accumulations are non-empty. repeating the procedure of step , replacing rightmost points by building the left accumulation and leftmost points by building the right accumulation, we will also, in a finite number of steps, obtain a set points xi such that xi ∈ [b + (i − )ν, b + (i − )ν + δ], i = , , . . . , n, for some b ∈ [ , ]. step . now we will show how one can get to the situation where all points lie inside the interval (a − ε, a + ε) starting from any configuration in which xi ∈ [b + iν, b + iν + δ], i = , , . . . , n − , ( . ) where b ∈ [ , ] and x < · · · < xn− are the core points of the configuration (i.e., with the extreme point removed). we have shown in step and step how we can achieve such a configuration in a finite time with a positive probability. suppose that a > b; the argument for the other case is entirely analogous. we describe an event of positive probability by which the entire configuration can be moved to the right. having just removed the extreme point, we stipulate that the new point y belong to (b + nν − δ, b + nν − δ), so y > xn− is the new rightmost point provided δ < ν/ . then to ensure that x , and not y , is the most extreme point we need x + y − [ b + ν n + ] < x + · · · + xn− + y n − [ b + ν n + ] . the left-hand side of the last inequality is less than − δ while the right-hand side is more than − δ n , so the inequality is indeed satisfied provided n ≥ . b + ν ✲✛ δ ✉ b + ν ✲✛ δ ✉ · · · b + (n − )ν ✲✛ δ ✉ b + nν ✛ ✲✛✲ δ δ ✉ figure : schematic of a configuration at the start of step . the disks represent the points x , x , . . . , xn− and, on the extreme right, the new point y . hence at the next step x is removed. our new collection of core points is x < · · · < xn− < y . we stipulate that the next new point y arrive in (b + (n + )ν − δ, b + (n + )ν − δ). so again, for δ small enough (δ < ν/ suffices), y > y and the newly added point (y ) becomes the rightmost point in the configuration. again, to ensure that the leftmost point (x ) is now the extreme one, we require x + y − [ b + ν n + ] < x + · · · + xn− + y + y n − [ b + ν n + ] . the left-hand side of the last inequality is less than − δ, while the right-hand side is more than − δ/n, and so the displayed inequality is true provided n ≥ . we will repeat this process until we remove the rightmost core point present at the start of step , namely xn− , located in [b + (n − )ν, b + (n − )ν + δ]. we will randomized keynesian beauty contest demonstrate how we can do this, in succession removing points from the left of the configuration and at each step replacing them by points on the right with careful choice of locations for the new points. we consecutively put new points yk at locations in intervals ∆k := (b + (n − + k)ν − · kδ, b + (n − + k)ν − · kδ + δ), for k = , , . . . , n − . we have just shown that for k = , this procedure will maintain the leftmost point (xk) as the extreme one. let us show that this is true for all ≤ k ≤ n − , by an inductive argument. indeed, suppose that the original points x , x , . . . , xk− have been removed, the successive new points yj are located in ∆j, j = , , . . . , k − , and that the replacement for the most recently removed point xk− is the new point yk. place the new point yk in ∆k. provided δ < ν · k− + , yk > yk− and yk is the rightmost point of the new configuration, while the leftmost point is xk ∈ [b + νk, b + νk + δ]. since n ≥ we have xk + yk ≤ b + [ n − + k ] ν − [ k − ]δ ≤ b + [ n − + k ] ν − ( + + · · · + k)δ n ≤ xk + · · · + xn− + y + · · · + yk n , thus ensuring that the leftmost point xk, and not yk, is the farthest from the centre of mass. thus, provided δ < −nν, say, we proceed to remove all the points xk and end up with a new collection of points x′ , . . . , x ′ n− satisfying the property x′i ∈ [b ′ + iν, b′ + iν + δ′], i = , , . . . , n − , where b′ = b + (n − )ν − δ′ and δ′ := nδ (> · n− δ). thus the situation is similar to the one in ( . ) but with b replaced by b′ > b + ν, so the whole “grid” is shifted to the right. hence, provided δ is small enough, and δ′ and its subsequent analogues remain such that δ′ < −nν, we can repeat the above procedure and move points to the right again, etc., a finite number of times (depending on |b−a|/ν) until the moment when all the new points are indeed in (a − ε, a + ε), and the probability of making all those steps is strictly positive. in particular, we can check that taking δ < − n/νν will suffice. all in all, we have performed a finite number of steps, which can be bounded above in terms of n, ρ, and ε but independently of a, and each of which required a u[ , ] variable to be placed in a small interval (of width less than −nν) and so has positive probability, which can be bounded below in terms of n, ρ, and ε. so overall the desired transformation of the configuration has positive probability depending on n, ρ, and ε, but not on a. this completes the proof of the lemma. proof of proposition . . write µ′(t) := µn− (x ′ n(t)). let i ⊆ [ , ] be a non-null interval. we can (and do) choose a ∈ ( , ) and ε′ > such that i′ := [a−ε′, a+ε′] ⊆ i. also take i′′ := [a − ε, a + ε] ⊂ i′ for ε = ( bc)− n− / ε′, where c is the constant in lemma . and b ≥ is an absolute constant chosen so that ε < ε′/ for all n ≥ . fix ρ ∈ ( , ). it follows from lemma . that, for some δ > and t ∈ n, depending on ε, p[{µ′(t ) ∈ i ′′} ∩ {d(t ) ≤ ε} | xn ( )] ≥ δ (sρ). michael grinfeld, stanislav volkov, andrew r. wade by lemma . , we have that d(t ) ≤ ε implies that f(t ) ≤ nε < (ε′/( bc)) , so that t ≥ νε′/( bc), where ν· is as defined just before lemma . . applying lemma . with this choice of t and with the ε there equal to ε ′/( bc), we obtain, by markov’s inequality, p [ max t≥t |µ′(t) − µ′(t )| ≤ ε ′/ | ft ] ≥ / , a.s. it follows that, given xn( ), the event {µ′(t ) ∈ i ′′} ∩ {d(t ) ≤ ε} ∩ {|ξn − µ ′(t )| ≤ ε ′/ } has probability at least (δ / ) (sρ), and on this event we have |ξn −a| ≤ ε+( ε ′/ ) < ε′, so ξn ∈ i. hence ( . ) follows. for the final statement in the proposition, suppose that xn( ) consists of independ- ent u[ , ] points. in this case mn( ) defined at ( . ) is the minimal spacing in the induced partition of [ , ] into n + segments, which has the same distribution as n+ times a single spacing, and in particular has density f(x) = n(n + )( −(n + )x)n− for x ∈ [ , n+ ] (cf section a). hence for any ρ ∈ [ , n+ ], we have p[sρ] = ( − (n + )ρ)n, which is positive for ρ = n , say. thus taking expectations in ( . ) yields the final statement in the proposition. . . explicit calculations for n = for this section we take n = , the smallest nontrivial example. in this case we can perform some explicit calculations to obtain information about the distribution of ξ . in fact, we work with a slightly modified version of the model, avoiding certain ‘boundary effects’, to ease computation. specifically, we do not use u[ , ] replacements but, given x (t), we take ut+ to be uniform on the interval [min x ′ (t)− d(t), max x ′ (t)+ d(t)]. if this interval is contained in [ , ] for all t, this modification would have no effect on the value of ξ realized (only speeding up the convergence), but the fact that now ut+ might be outside [ , ] does change the model. for this modified model, the argument for theorem . follows through with minor changes, although we essentially reprove the conclusion of theorem . in this case when we prove the following result, which gives an explicit description of the limit distribution. here and subsequently ‘ d =’ denotes equality in distribution. proposition . . let d = and n = and work with the modified version of the process just described. let x ( ) consist of distinct points in [ , ]. write µ := µ (x ′ ( )) and d := d (x ′ ( )). there exists a random ξ := ξ (x ( )) ∈ r such that x ′ (t) a.s. −→ (ξ , ξ ) as t → ∞. the distribution of ξ can be characterized via ξ d = µ + dl, where l is independent of (µ, d), l d = − l, and the distribution of l is determined by the distributional solution to the fixed-point equation l d =          − +u + ul with probability − −u + u l with probability −u + u l with probability +u + ul with probability , ( . ) randomized keynesian beauty contest where e[|l|k] < ∞ for all k, and u ∼ u[ , ]. writing θk := e[l k], we have θk = for odd k, and θ = , θ = , and θ = . in particular, e[ξ ] = e[µ], e[ξ ] = e[µ ] + e[d ], and e[ξ ] = e[µ ] + e[µd ]. ( . ) in the case where x ( ) contains independent u[ , ] points, e[ξ k ] = , , for k = , , respectively. if x ( ) = ( , , ), then e[ξk ] = , , , for k = , , , . we give the proof of proposition . at the end of this section. first we state one consequence of the fixed-point representation ( . ). proposition . . l given by ( . ) has an absolutely continuous distribution. proof. it follows from ( . ) that p [ l = ] = p [ u ( l − ) = ] + p [ u ( l + ) = ] + p [ u ( l − ) = ] + p [ u ( l + ) = ] . the first two terms on the right-hand side of the last display are zero, by an application of the first part of lemma b. with x = u, y = l± / , and a = , . also, since u > a.s., p[u(l ∓ ) = ] = p[l = ± ], and, by symmetry, p[l = / ] = p[l = − / ]. thus we obtain p [ l = ] = p [ l = ] + p [ l = − ] = p [ l = ] . hence p[l = / ] = p[l = − / ] = . each term on the right-hand side of ( . ) is of the form ± + v (l ± ) where v is an absolutely continuous random variable, independent of l (namely u or u/ ). the final statement in lemma b. with the fact that p[l = ± / ] = shows that each such term is absolutely continuous. finally, lemma b. completes the proof. in principle, the characterization ( . ) can be used to recursively determine all the moments e[lk] = θk, and the moments of ξ may then be obtained by expanding e[ξk ] = e[(µ+dl) k]. however, the calculations soon become cumbersome, particularly as µ and d are, typically, not independent: we give some distributional properties of (µ, d) in the case of a uniform random initial condition in appendix a. before giving the proof of proposition . , we comment on some simulations. figure shows histogram estimates for the distribution of ξ for two initial distributions (one deterministic and the other uniform random), and table reports corresponding mo- ment estimates, which may be compared to the theoretical values given in proposition . . in the uniform case, we only computed the first moments analytically, namely, , , as quoted in proposition . ; it is a curiosity that these coincide with the first moments of the u[ , ] distribution. proof of proposition . . let µ′(t) := (x( )(t) + x( )(t)) and d(t) := |x( )(t) − x( )(t)| denote the mean and diameter of the core configuration, repeating our notation from above. consider separately the events that ut+ falls in each of the four intervals [min x ′ (t) − d(t), min x ′ (t)), [min x ′ (t), min x ′ (t) + d(t)), [min x ′ (t) + d(t), max x ′ (t)), [max x ′ (t), max x ′ (t) + d(t)], michael grinfeld, stanislav volkov, andrew r. wade − − . . . . − . . . . . . . . . . . . figure : normalized histograms based on simulations of the modified n = model with fixed {− / , / , } initial condition (left) and i.i.d. u[ , ] initial condition (right). k ± core . . . . − . . u[ , ] . . . . . . table : empirical kth moment values (to decimal places) computed from the simulations in figure . which have probabilities , , , respectively. given (µ′(t), d(t)), we see, for vt+ a u[ , ] variable, independent of (µ′(t), d(t)), (µ′(t + ), d(t + )) =          (µ′(t) − +vt+ d(t), vt+ d(t)) with prob. (µ′(t) − −vt+ d(t), vt+ d(t)) with prob. (µ′(t) + −vt+ d(t), vt+ d(t)) with prob. (µ′(t) + +vt+ d(t), vt+ d(t)) with prob. . ( . ) writing mk(t) = e[d(t) k | x ( )] we obtain from the second coordinates in ( . ) mk(t + ) = e[v kt+ ]mk(t) + −ke[v kt+ ]mk(t), which implies that mk(t) = ( (k + ) ( + −k) )t d( )k. ( . ) for example, m (t) = ( / ) td( ) and m (t) = ( / ) td( ) . next we show that µ′(t) converges. from ( . ), we have that |µ′(t+ )−µ′(t)| ≤ d(t), a.s., so to show that µ′(t) converges, it suffices to show that ∑∞ t= d(t) < ∞ a.s. but this can be seen from essentially the same argument as lemma . , or directly from the fact that the sum has nonnegative terms and e ∑∞ t= d(t) = ∑∞ t= e[m (t)], which is finite. hence µ′(t) converges a.s. to some limit, ξ say. extending this argument a randomized keynesian beauty contest little, we have from ( . ) that |µ′(t+ )| ≤ |µ′(t)|+d(t), a.s., and d(t+ ) ≤ vt+ d(t), a.s. hence for v , v , . . . i.i.d. u[ , ] random variables, we have d(t) ≤ v · · · vtd( ) and |µ′(t)| − |µ′( )| = t− ∑ s= (|µ′(s + )| − |µ′(s)|) ≤ ( + ∞ ∑ s= s ∏ r= vr ) d( ) =: ( + z)d( ). here z has the so-called dickman distribution (see e.g. [ , § ]), which has finite moments of all orders. hence e[|µ′(t)|p | x ( )] is bounded independently of t, so, for any p ≥ , (µ′(t))p is uniformly integrable, and hence limt→∞ e[(µ ′(t))k | x ( )] = e[ξk | x ( )] for any k ∈ n. we now want to compute the moments of ξ ; by the previous argument, we can first work with the moments of µ′(t). note that, from ( . ), e[(µ′(t + ) − µ′(t))k | x (t)] = + (− )k d(t)ke [ ( + vt+ )k ] + + (− )k d(t)ke [ ( + vt+ )k ] = + (− )k ( −k + − k) k+ − k + d(t)k, using the fact that e[( +vt+ ) k] = k+ − k+ . in particular, e[(µ′(t+ )−µ′(t))k | x (t)] = for odd k, so e[µ′(t) | x ( )] = µ ′( ), and hence e[ξ ] = limt→∞ e[µ ′(t)] = e[µ′( )], giving the first statement in ( . ). in addition, e[(µ′(t + )) − (µ′(t)) | x (t)] = µ′(t)e[µ′(t + ) − µ′(t) | x (t)] + e[(µ ′(t + ) − µ′(t)) | x (t)] = d(t) . hence e[(µ′(t)) − (µ′( )) | x ( )] = t− ∑ s= e[(µ′(s + )) − (µ′(s)) | x ( )] = t− ∑ s= m (s) → ∞ ∑ s= −sd( ) , as t → ∞, and the limit evaluates to d( ) , so that e[ξ ] = limt→∞ e[(µ ′(t)) ] = e[(µ′( )) ] + e[d( ) ], giving the second statement in ( . ). write l(µ′( ), d( )) = ξ (x ( )) emphasizing the dependence on the initial config- uration through µ′( ) and d( ). then by translation and scaling properties l(µ′( ), d( )) d = µ′( ) + d( )l( , ). ( . ) so we work with l := l( , ) (which has the initial core points at ± ). michael grinfeld, stanislav volkov, andrew r. wade we will derive a fixed-point equation for l. the argument is closely related to that for ( . ). conditioning on the first replacement and using the transformation relation ( . ), we obtain ( . ). from ( . ) we see that |l| is stochastically dominated by + u|l|; iterating this, similarly to the argument involving the dickman distribution above, we obtain that |l| is stochastically dominated by + z, where z has the dickman distribution, which is determined by its moments. hence ( . ) determines a unique distribution for l with e[|l|k] < ∞ for all k. writing ( . ) in functional form l d = Ψ(l), we see that by symmetry of the form of Ψ, also Ψ(l) d = − Ψ(−l). hence −l d = − Ψ(l) d = Ψ(−l), so −l satisfies the same distributional fixed-point equation as does l. hence l d = − l. writing θk := e[l k], which we know is finite, we get θk = k ∑ j= ( k j ) ( + (− ))jθk−je [ ( + u )j uk−j ] + k ∑ j= ( k j ) ( + (− ))jθk−je [ ( − u )j ( u )k−j ] . here e [ ( + u )j uk−j ] = −j j ∑ ℓ= ( j ℓ ) k − ℓ + =: a(k, j); e [ ( − u )j ( u )k−j ] = −k j ∑ ℓ= ( j ℓ ) (− / )j−ℓ k − ℓ + =: b(k, j). so we get θk = ∑ j even, j≤k ( k j ) θk−j( a(k, j) + b(k, j)). ( . ) in particular, as can be seen either directly by symmetry or by an inductive argument using ( . ), θk = for odd k. for even k, one can use ( . ) recursively to find θk, obtaining for example the values quoted in the proposition. note that, by ( . ), e[ξ ] = e[(µ ′( ) + ld( )) ], which, on expansion, gives the final statement in ( . ). the first moments in the case of the uniform initial condition follow from ( . ) and lemma a. . for the initial condition with points , , , we have d( ) = and µ′( ) = χ +( −χ) = − χ , where χ is the tie-breaker random variable taking values or each with probability . it follows that e[µ′( )k] = −k( k + k). then, using ( . ), e[ξk ] = e[(µ ′( ) + (l/ ))k] = −k k ∑ j= ( k j ) jθj( k−j + k−j). we can now compute the four moments given in the proposition. randomized keynesian beauty contest appendix a. uniform spacings in this appendix we collect some results about uniform spacings which allow us to obtain distributional results about our uniform initial configurations. the basic results that we build on here can be found in section . of [ ]; see the references therein for a fuller treatment of the theory of spacings. let u , u , . . . , un be independent u[ , ] points. denote the corresponding in- creasing order statistics u[ ] ≤ · · · ≤ u[n], and define the induced spacings by sn,i := u[i] −u[i− ], i = , . . . , n+ , with the conventions u[ ] := and u[n+ ] := . we collect some basic facts about the sn,i. the spacings are exchangeable, and any n-vector, such as (sn, , . . . , sn,n), has the uniform density on the simplex ∆n := {(x , . . . , xn) ∈ [ , ]n : ∑n i= xi ≤ }. we need some joint properties of up to spacings. any spacings have density f(x , x , x ) = n(n − )(n − )( − x − x − x ) n− on ∆ . we note that min{sn, , sn, } d = sn, , (n ≥ ), (a. ) (sn, , min{sn, , sn, }) d = (sn, , sn, ), (n ≥ ); (a. ) see for example lemma . of [ ]. finally, for any n ≥ and α ≥ , β ≥ , e[sαn, s β n, ] = Γ(n + )Γ(α + )Γ(β + ) Γ(n + + α + β) . (a. ) in particular e[skn, ] = n!k! (n+k)! for k ∈ n. our main application in the present paper of the results on spacings collected above is to obtain the following result, which we use in section . . lemma a. . let d = and n = . suppose that x ( ) consists of independent u[ , ] points. then (µ (x ′ ( )), d (x ′ ( ))) d = ((s + s )ζ + ( − s − s )( − ζ), s ), where ζ is a bernoulli random variable with p[ζ = ] = p[ζ = ] = / . for k ∈ z+, e[(d (x ′ ( ))) k] = −k (k + )(k + )(k + ) , (a. ) e[(µ (x ′ ( ))) k] = ( k − + ( k+ − ) −(k+ )) (k + )(k + )(k + ) . (a. ) so, for example, the first moments of d (x ′ ( )) are , , and , while the first moments of µ (x ′ ( )) are , , and . finally, e[µ (x ′ ( ))(d (x ′ ( ))) ] = . proof. the points of x ( ) induce a partition of the interval [ , ] into uniform spacings s , s , s , s , enumerated left to right (for this proof we suppress the first index in the notation above). for ease of notation, write d := d (x ′ ( )) and µ := µ (x ′ ( )) for the duration of this proof. then d = min{s , s } d = s / , by (a. ). moreover, min{s , s } is equally likely to be either s or s . in the former case, michael grinfeld, stanislav volkov, andrew r. wade µ = s + min{s , s }, while in the latter case µ = − s − min{s , s }. using (a. ), we obtain the following characterization of the joint distribution of µ and d. (µ, d) d = { (s + s , s ) with probability ( − s − s , s ) with probability . (a. ) hence e[dk] = −ke[sk ], which gives (a. ) by the n = , α = k, β = case of (a. ). for the moments of µ, we have from (a. ) that µ has the distribution of w := s + s with probability / or − w with probability / . so we have e[µk] = e[w k] + e[( − w)k] = wk + k ∑ j= ( k j ) (− )jwj, where wk := e[w k]. since wk = e[(s + s ) k], we compute wk = k ∑ j= ( k j ) −je[s k−j s j ] = k! (k + )! k ∑ j= −j, by the n = , α = k − j, β = j, case of (a. ). thus we obtain wk = ( − −(k+ )) (k + )(k + )(k + ) . it follows that e[µk] = wk + k ∑ j= k! (j + )!(k − j)! (− )j − k ∑ j= k! (j + )!(k − j)! (− / )j. we deduce (a. ), after simplification, from the claim that, for any z ∈ r, s(z) := k ∑ j= k! (j + )!(k − j)! (−z)j = k! z (k + )! [ z (k + )(k + ) + − z(k + ) − ( − z)k+ ] . (a. ) thus it remains to verify (a. ). to this end, note that s(z) = k! (k + )! k ∑ j= ( k + j + ) (−z)j = k! (k + )!  −z− k+ ∑ j= ( k + j ) (−z)j + z− ( k + ) − z− ( k + ) + z− ( k + )   = k! z (k + )! [ −( − z)k+ + z (k + )(k + ) − z(k + ) + ] , which gives the claim (a. ). randomized keynesian beauty contest for the final statement in the lemma, we have from (a. ) that e[µd ] = e[(s + s )( s )] + e[( − s − s )( s )] = e[s ] = , by (a. ). this completes the proof of the lemma. we can also obtain explicit expressions for the densities of d and µ. since d d = s / , the density of d is fd(r) = ( − r) for r ∈ [ , / ]. in addition, µ has density fµ given by fµ(r) =      r[ ( − r) − r] if r ∈ [ , / ] − r( − r) if r ∈ [ / , / ] ( − r)[ r − ( − r)] if r ∈ [ / , ] . (a. ) indeed, with the representation of µ as either w or −w with probability / of each, we have p[µ ≤ r] = p[w ≤ r] + ( − p[w < − r]). assuming that w has a density fw (which indeed it has, as we will show below), we get fµ(r) = fw (r) + fw ( − r). (a. ) using the fact that w d = s + s , we use the joint distribution of (s , s ) to calculate p[w ≤ r] = ∫ dx ∫ −x dx ( − x − x ) {x + x ≤ r} = ∫ r dx ∫ ( (r−x ))∧( −x ) dx ( − x − x ). after some routine calculation, we then obtain p[w ≤ r] = { − ( − r) + ( − r) if r ∈ [ , / ] − ( − r) if r ∈ [ / , ]. hence w has density fw given by fw (r) = { ( − r) − ( − r) if r ∈ [ , / ] ( − r) if r ∈ [ / , ]. then (a. ) follows from (a. ). appendix b. continuity of random variables in this appendix we give some results that will allow us to deduce the absolute continuity of certain distributions specified as solutions to fixed-point equations: spe- cifically, we use these results in the proof of proposition . . the results in this section may well be known, but we were unable to find a reference for them in a form directly suitable for our application, and so we include the (short) proofs. lemma b. . let x and y be independent random variables such that x has an absolutely continuous distribution. then for any a = we have p[xy = a] = . moreover, if p[y = ] = , then xy is an absolutely continuous random variable. michael grinfeld, stanislav volkov, andrew r. wade proof. for the moment assume that p[x < ], p[x > ], p[y < ], and p[y > ] are all positive. take some < c < d. then p[xy ∈ (c, d)] = p[log(x) + log(y ) ∈ (log c, log d) | x > , y > ]p[x > ]p[y > ] +p[log(−x) + log(−y ) ∈ (log c, log d) | x < , y < ]p[x < ]p[y < ]. note that conditioning x on the event x > (or x < ) preserves the continuity of x and the independence of x and y . then since the sum of two independent random variables at least one of which absolutely continuous is also absolutely continuous (see [ , theorem . , p. ]) we have p[log(x) + log(y ) ∈ (log c, log d) | x > , y > ] = ∫ log d log c f+(x)dx, and p[log(−x) + log(−y ) ∈ (log c, log d) | x < , y < ] = ∫ log d log c f−(x)dx, for suitable probability densities f+ and f−. after the substitution u = e x, this yields p[xy ∈ (c, d)] = ∫ d c p[x > ]p[y > ]f+(log u) + p[x < ]p[y < ]f−(log u) u du. this expression is also valid if some of the probabilities for x and y in the numerator of the integrand are zero. therefore, we have, for any < c < d, p[xy ∈ (c, d)] = ∫ d c f(u)du, (b. ) for some function f(u) defined for u > . a similar argument applies to the case c < d < ; then (b. ) is valid for any c < d < as well, extending f(u) for strictly negative u. in particular, it follows that p[xy = a] = for a = . now if p[y = ] = , then p[xy = ] = . then we can set f( ) = so that (b. ) holds for all c, d ∈ r. this completes the proof. lemma b. . suppose that a random variable l satisfies the distributional equation l d =        z with probability p ... zn with probability pn, where n ∈ n, ∑n i= pi = , pi > , and each zi is an absolutely continuous random variable. then l is absolutely continuous. proof. suppose zi has a density fi. then for any −∞ ≤ a < b ≤ +∞ we have p[l ∈ (a, b)] = n ∑ i= pip[zi ∈ (a, b)] = n ∑ i= pi ∫ b a fi(x)dx = ∫ b a [ n ∑ i= pifi(x) ] dx, which yields the statement of lemma. randomized keynesian beauty contest acknowledgements parts of this work were done at the university of strathclyde, where the third author was also employed, during a couple of visits by the second author, who is grateful for the hospitatlity of that institution. references [ ] benassi, c. and malagoli, f. the sum of squared distances under a diameter constraint, in arbitrary dimension. arch. math. ( ) – . [ ] de giorgi, e. and reimann, s. the α-beauty contest: choosing numbers, thinking intervals. games econom. behav. ( ) – . [ ] erdős, p. on the smoothness properties of a family of bernoulli convolutions. amer. j. math. ( ) – . [ ] grinfeld, m., knight, p.a. and wade, a.r. rank-driven markov processes. j. stat. phys. ( ) – . [ ] hughes, b.d. random walks and random environments; volume : random walks, clarendon press, oxford, . [ ] johnson, n.l. and kotz, s. use of moments in studies of limit distributions arising from iterated random subdivisions of an interval. statist. probab. lett. ( ) – . [ ] keynes, j.m. the general theory of employment, interest and money, macmillan, london, . [ ] krapivsky, p.l. and redner, s. random walk with shrinking steps. amer. j. phys. ( ) – . [ ] moran, p.a.p. an introduction to probability theory, clarendon press, oxford, (paperback ed., with corrections, ). [ ] moulin, h. game theory for the social sciences, nd ed., new york university press, new york, . [ ] muratov, a. and zuyev, s. lisa: locally interacting sequential adsorption, stoch. models ( ) – . [ ] pemantle, r. a survey of random processes with reinforcement. probab. surv. ( ) – . [ ] penrose, m.d. and wade, a.r. random minimal directed spanning trees and dickman-type distributions. adv. in appl. probab. ( ) – . [ ] penrose, m.d. and wade, a.r. limit theory for the random on-line nearest-neighbor graph. random structures algorithms ( ) – . [ ] pillichshammer, f. on the sum of squared distances in the euclidean plane. arch. math. ( ) – . [ ] witsenhausen, h.s. on the maximum of the sum of squared distances under a diameter constraint. amer. math. monthly ( ) – . wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ thebeautifulandthepolitical canterbury christ church university’s repository of research outputs http://create.canterbury.ac.uk please cite this publication as follows: redhead, l. ( ) the beautiful and the political. contemporary music review, ( ). pp. - . issn - . link to official url (if available): http://dx.doi.org/ . / . . this version is made available in accordance with publishers’ policies. all material made available by create is protected by intellectual property law, including copyright law. any use made of the contents should comply with the relevant law. contact: create.library@canterbury.ac.uk the beautiful and the political lauren redhead competing and polarised positions related to the possible political nature of material in contemporary music are exemplified by the work of postmodern composers and of post-war modernist composers. whilst the former argue for the political nature of their compositions by the inclusion of contemporary issues and imagery, the latter argue for the political nature of their manipulation of otherwise politicaly neutral musical material. this opposition can be understood as a dialectic between content and form, and is expressed by adorno as the opposition between representational and ‘committed ’ work. this paper examines one example of each type of work—luigi nono’s il canto sospeso ( - ) and johannes kreidler’s audioguide—and their relationship to a conception of the ‘beautiful’ in music. these expressions of the ‘political’ offer a ramework through which the musicaly beautiful can be interrogated in the opposition of committed and autonomous artworks, and understood as an experience of alienation. eco's exploration of entfremdung and kristeva's concept of abjection can both be employed to argue that the ‘political’ dimension of autonomous works offers the potential for a radical experience of beauty as a transcendence derived rom present conditions, whilst committed works negate beauty as a condition of re-presenting the present. keywords: beauty, postmodernism, post-war modernism, alienation, abjection • the subject of beauty is not often discussed in relationship to the question of politics in music; the topic does not often come up in questions of aesthetics in late twentieth and early twenty- first century music at all. perhaps this is because concerns of the material and the political seem to negate or take precedence over the concept of the musically beautiful, or because a modernist approach to composition conceives of material in the abstract, yielding the formalist view that the perception of beauty arises from the perception of the poietic process. however the concept of beauty does have something to add to the discussion of politics in recent music, and in particular to the understanding of the possible links between compositional aesthetics and the political. the most commonly invoked sense of the word ‘beauty’ is a popular construction of the term that has its roots in nineteenth century aesthetics. this links beauty with potentially separate ideas of transcendence or of the sublime, of aesthetic experience, and in many more informal conceptions with the tonal narratives of nineteenth century music. in this understanding, ‘transcendence’ is the key concept, and the link of transcendence with tonality possibly prevents the understanding of atonal works as beautiful. the ‘journey of transcendence’—from worldly to otherworldly experience—is closely allied with the tonal journey. however, the history of aesthetics is supposed to chart the re-thinking of beauty, in line with the art and understanding of the present. there are many, competing, and non-transcendental narratives of beauty to be found in the aesthetic philosophy of the past. these reflect the social and artistic circumstances of the time, for example the use of religious references in the works of tinctoris and zarlino, the appeal to reason in plato, the appeal to scientific proportions in the enlightenment, and the linking of beauty with virtue in the work of ficino. a single theory does not encompass beauty or aesthetic experience throughout the history of music, and the theories of the past would address contemporary art equally as badly as does a transcendent theory of beauty. in addition, such theories of beauty also speak to the transient nature of the description of beauty and the aesthetic experience throughout history. both the marginalisation of music aesthetics within philosophy and music, and the capitalist reliance of the musical institutions on the reproducibility of tonal music, play a role in the problem of the lack of deviation from the tonal conception of beauty in musical discourse today. exceptions can, of course, be found, and one of these is lachenmann’s ( ) treatise on beauty. lachenmann describes exactly this problem of the mis-identification of beauty, and the use of the beauty-narrative as a cover for nostalgia and conservatism, in the following statement: today the call for beauty is more suspect than ever—whether the concept is a pluralism embracing all conceivable types of hedonism, or else a reactionary hangover after false hopes and promises, or just academicism of whatever sort. its proponents betray themselves over and over again as they cry out for ‘nature’, for tonality, for something positive, ‘constructive’, for ‘comprehensibility at last’ and respond with loyal quotations from bruckner, mahler and ravel. it is high time the concept of beauty be rescued from the speculations of corrupt spirits, and the cheap pretensions of avant-garde hedonists, sonority-chefs, exotic-meditationists and nostalgia-merchants. once integrated into an overall theory of aesthetics and composition, the concept is no longer suitable for the prophets of popularity, the apostles of nature and tonality, and the fetishists of academicism and tradition. the mission of art lies neither in fleeing from, nor in flirting with, the contradictions which mould the consciousness of our society, but in coming to grips with them and dialectically mastering them. ( , p. ) lachenmann’s complaint bears the traces of a modernist approach to music, but his call for the radical reinterpretation of beauty also bears many similarities with umberto eco’s description of alienation in the open work (eco, ). eco outlines three types of alienation: rejection, alienation from or verremdung, and alienation in/to or entremdung, of which the last is the most important. entremdung is alienation within a formal system, which involves dialectical tension between invention and manner, and between freedom and formal restrictions. eco claims that by obeying the formal conventions of tonality, the composer has let the system ‘act on its own’ ( , p. ). tonal works written in the present day are considered formally devoid of meaning that is of relevance to the present day; tonality is thought only to express ideas of relevance to the society which conceived of it. composers, eco says, revolted against the tonal system not merely because it made it impossible for them to say the things they wished to say, but ‘because its structure mirrors or embodies a world view’ (that does not or should not belong to contemporary society: , p. ). indeed, eco believes that formal conventions in tonal music, and states of mind, emotion or cognition, are so strong that they have become ingrained: ‘the listener can no longer hear them without instinctively relating them to a particular moral, ideological, or social reality’ ( , p. ). as a result, the atonal composer expresses ‘[their] refusal of a system of communication that guarantees [them] an audience if, and only if, [they are] willing to submit to an obsolete value system’ ( , p. ). therefore, the rejection of the tonal system alienates the composer in/to an undesirable set of cultural values. eco writes that the tonal system is able to communicate only ‘in appearance’ ( , p. ). this is because ‘language offers us a representation of the phenomenal world that has nothing to do with the one we encounter on a daily basis’ ( , p. ). therefore, the artist who protests through form (in this case through rejection of tonality) transforms the tonal system by alienating themselves to it, and accepts a social world in crisis by forming a system that exists on disorder (within the previous system). thus, eco is clear that alienation is the goal of the artist and of art, and this type of alienation is the beauty that lachenmann describes. it also holds a lot in common with a description of aesthetic experience which, far from being a comfortable confirmation of tonal expectations, is rather a radical encounter with art. for eco, and for lachenmann, confirmation of (tonal) expectation interrupts this experience, since alienation is precluded by the re-enforcing of tonality’s ‘particular moral, ideological, or social reality’. both lachenmann and eco support the idea that composition with particular materials can, in and of itself, be political, and that musical politics can be gleaned as a facet of aesthetic experience, and not solely in direct action arising from the experience of music. further support for this point of view can be found in adorno’s work. in the short essay ‘commitment’ adorno ( ) reflects on political aesthetics in literature. adorno challenges the idea—which comes from jean paul sartre—that committed art is the only type of art that can challenge power structures in society. committed art, in adorno’s conception, has an overt political message, whilst autonomous art has no overt message and serves itself. this does not preclude autonomous art from being political, but creates the possibility for artworks that serve longer term political goals. adorno’s examples are the theatrical works of brecht and beckett. brecht’s more abstract works are deemed to be most aesthetically successful, but beckett’s works more successful still since he is ‘uncommitted’. in comparison, writes adorno, committed works seem ‘like pantomimes’ ( , p. ). indeed, adorno points out the role of performance in representing reality, as in epic theatre, rather than illuminating it, as in beckett’s work. performance and representation, then, are not the only route to political meaning in art; adorno writes that the focus on autonomy, as in his criticism, is also ‘sociopolitical in nature’ ( , p. ).’ these competing positions in literature can also be found in music today, and a particular opposition between the work of post-war modernist composers, and postmodern composers can be identified. competing and polarised positions, related to the possible political nature of material in contemporary music, are exemplified by the work that falls under these two terms. whilst composers of the former argue for the political nature of their composition by, for example, the inclusion of contemporary issues and imagery as materials in their works, composers of the latter argue for the political nature of their manipulation of otherwise politically neutral musical material. these polarised positions are represented in facets of two musical examples that this article will briefly touch upon: il canto sospeso ( - ) by italian composer luigi nono, as a representative example of post-war modernism, and johannes kreidler’s seven-hour work audioguide ( ), which was premiered at darmstadt in as a representative example of the postmodern in music. this opposition can be understood as a dialectic between content and form, that adorno expresses by using ‘commitment’ as the opposition between ‘committed’ and autonomous work. i’ll briefly make references to the materials of these two works, but will give a greater focus to the possibilities for aesthetic experience and the perception of beauty in each, and the possible link of these with the conception of the political. il canto sospeso is perhaps one of the most well-known examples of engagierte musik (socially committed music). its basic materials and inspirations can perhaps be divided into two categories: those which might be thought of as musically autonomous, and those which might come under the category of ‘committed’. the music contains many elements and permutations of serial organisation—and other structured methods of organisation which are not necessarily serial—and can be thought of as a cantata for voices and large ensemble. luigi nono has also explicitly stated the influences of maderna, varèse and scriabin on the sound-world of the music (nono, in nielinger, , p. ). these aspects of the work—a highly structured kreidler has endorsed the term ‘new conceptualism’ within a public debate around this post-modern approach to music. within this debate, ‘neo-conceptualism’ has been suggested by critics of this compositional approach who compare it unfavourably with developments in visual arts in the s. and regulated poietic process, the necessity of concert-hall presentation, the difficulty of the instrumental and vocal parts, which require performance by highly specialised individuals—fit well with the definition of autonomous music, in adorno’s terms. however, the title of the piece comes from a poem in english by ethel rosberg. nono’s title translates as ‘the suspended song’ which in the original english appears as ‘the song unsung’; the texts used in the work contain fragments of letters written by ten freedom fighters facing execution from six countries (including the ussr, poland, greece, italy, germany and bulgaria), and there can also be said to be a direct influence of schoenberg’s a survivor rom warsaw ( ). on the level of text, then, there is an element of commitment. recent analyses of the work have sought to bring out the multi-faceted use of compositional technique in the piece. carola nielinger ( ) and kathryn bailey ( ) both address the poietics of the music in some considerable detail, and both point out that musicological assumptions about the use of serialism in the work, mostly derived from reginald smith- brindle’s analysis of serialist technique in only one of its movements, have neglected the depth of technical variation in the music (bailey, , p. ). both nielinger and bailey draw special attention to the final instrumental section of the work: its th movement. in these analyses, both musicologists give special focus to operations in pitch, dynamics, instrumentation and texture, and what nielinger calls the ‘structural use of density’ ( , p. ), but also point out the levels on which the work evades analysis. nielinger’s assessment uses nono’s sketch material to compare the resultant score to the initial plans for the work, and bailey, who did not have access to the sketches when completing her analysis, expresses even more puzzlement at the work’s construction. she writes, ‘i have come to the conclusion that while i can explain the organisation of several parameters of this work there are still many important decisions for which i can offer no explanation’ ( , p. ), and later that the th movement has ‘proven to be resistant’ to her efforts ( , p. ). her lack of reference to the sketches perhaps brings her analytical conclusions closer to those of listeners who are, for the most part, in the same position. the level at which this work appears to evade analysis is perhaps the most interesting to my discussion. both nielinger and bailey are interested in poiesis but do little to address the esthesic level of the work. in fact, bailey begins her analysis by drawing attention to the impossibility of the esthesic process to engage with the many levels of parametric operations in works of integral or multiple serialism ( , p, ). this esthesic process is perhaps the literal ‘song unsung’ in this work: the ability of the music to express the inexpressible is what cannot be discovered by formalist analysis. nono’s analysts are surprised not to find in the score what was, perhaps, never resident there in the first place. despite the idea that the selection of particular materials could be legitimately described as political, this work can be described as more than the sum of its materials. of course aesthetic experience is an esthesic process, occurring between the listener and the work, and this radical experience of incomprehension, even in the face of an overwhelming amount of analytical data fits, the definition of entremdung: il canto sospeso is political not only in its materials but in the listener’s relationship to them, and in this respect it is also beautiful. in contrast, johannes kreidler’s audioguide ( - ) more readily gives up its poetics, despite its length. the work was primarily composed ‘in public’: anyone who follows kreidler on facebook, twitter, youtube or his website would have been able to view the images, sounds and ideas that he uploaded regularly during the compositional process. the piece has been created for four actors, six musicians, videos, sound, and ‘guests’. the seven hour performance includes many quotations, including from kreidler’s own works, a tirade against the reproduction of ‘dusty’ old artforms from past times—including by composers such as helmut lachenmann, mathias spahlinger and klaus huber—that finds support from hegel, the destruction of a large number of violins on stage (a penchant of kreidler’s perhaps, or a reference to his destruction of a ‘cello and a violin in a his protestaktion work), and a meta- analysis of the piece itself, given on stage by the composer towards the end. audioguide enacts, or performs, many of the ideas that have become associated with postmodernism in art and music in its eclecticism, irony, anti-historicism, and irreverence. some aspects of the piece might be seen to be autonomous: the durational aspect of its somewhat extreme length is perhaps a political statement in itself, and there are some periods of instrumental music without accompaniment. but there can be little doubt about the ‘committed’ status of the work. this is borne out in the readily recognisable nature of many of the images, videos, and quotations used. unlike in nono’s work, this is an intervention of the composer in the esthesic process. for eco, the potential for unlimited semiosis is present in both modernist and postmodern artworks, but in audioguide this is stunted by kreidler’s popular culture signifiers: they are, by their nature, immediately accessible, unlike nono’s subtle manipulations of musical parameters, but this also limits their potential for future meaning. this is perhaps most explicit in sections of the work such as that which uses imagery of the attack on the world trade centre on the th september . here, kreidler links western music with violence, just as authors such as susan mcclary ( ) and kofi agawu ( ) have done. however, unlike mcclary’s and agawu’s assessment of music in its sociocultural context, this music removes both the musical and social contexts from the one might note the duration of the longest work previously premiered at darmstadt, morton feldman’s string quartet no. ( ) of around . hours in duration, the six-hour concert presented at the close of the darmstadt summer course in and much commented upon for its duration, and the fact that audioguide is a full hour longer than even this; a fact that cannot have escaped the composer. audience’s consideration. notation and imagery stand in a synecdochic relationship with both music and ‘the political’, evoking both but potentially commenting on neither. the issue of unlimited semiosis is one which can also be raised with respect to the esthesic process in the case of this music. whilst this process of listener associations cannot be completely delineated—something held up as a central idea within a postmodern conception of art—the obviousness of intended meaning in the choice of some signifiers also cannot be relied upon. as well as invoking both the abstract ideas of music and politics, kreidler clearly also intends to invoke stockhausen’s oft-quoted statement that these terrorist attacks were ‘the greatest work of art possible in the cosmos’ and that they achieved ‘something in one act’ that ‘we couldn’t even dream of in music’ (e.g. tommasini, ). however, british listeners may also be reminded of the same idea evoked in chris morris’s creation nathan barley. morris’s satire takes in stockhausen, banksy and a superficial postmodernism found in hipster culture, but kreidler’s work also invites this (quite probably) unwanted association. the issue here is not one of the intent of the composer, but of the potential for the understanding and experience of the work. just as the ‘beauty’ of il canto sospeso arguably exists outside of its musical parameters, so a potentially disruptive political message can be identified outside of audioguide, in possible inter-objective comparison materials. these have been two very short and very specific examples, but their central point is that the comparison of the political aesthetics of these composers can be most usefully situated in the esthesics rather than the poietics of the music. recent anti-aesthetic thought has recognised ‘aesthetics’ itself within the th century to perpetuate an institutionalised concept of beauty rather than one arising from artworks, and kreidler’s work does attempt to reject any institutionalised aesthetics in both its content and its presentation. jacques rancière, makes explicit the way in which aesthetic definitions arise from social, and not from artistic perceptual-, truth-, or beauty-related concerns, calling this ‘the aesthetic regime of the arts’, when he writes, [a]rt is no longer identified as a specific difference within ways of doing or through criteria of inclusion and evaluation, allowing one to judge artistic conceptions and applications, but as a mode of sensible being specific to its products ( a, p. ). and reported widely in the popular press. in particular the images contained within the enclosed book with morris ( ) nathan barley, fucking with your head yeah? pp - ; pp - ; pp - . this emphasises the notion that cultural conditions are as important in the definition of art and beauty as the artworks themselves. but rancière also outlines the problem of experience, which indicates that there may yet be a salvageable aesthetic experience, separate from the aesthetic regime of the arts, when he writes: at the most general level […] there is meaning in what seems not to have any meaning, something enigmatic about what seems self-evident, a spark of thought in what appears to be an anodyne detail. these figures are not the materials upon which analytic interpretation proves its ability to interpret cultural formation. they are testimony to the existence of a particular tension between thought and non-thought, a particular way that thought is present within the sensible materiality, meaning within the insignificant, and an involuntary element within conscious thought ( b, p. ). a frequent criticism of political responses in music—particularly those of musical modernism —is that if political success can be seen in the subsequent effects of the work then few works have had any discernible effect at all. in light of this, the political successes of the ‘nutcracker group’ in the netherlands might be contrasted with the lasting musical, but not political, legacy of the work of cornelius cardew. there might be a tension between the highly organised nature of the musical materials in nono’s work and its political aims; adorno ( , p. ) associated integral serialism with totalitarian regimes and possibly would not agree with my application of his thought to endorse this music, but there is also a tension between the highly political agenda of kreidler’s work and the observation that nature of his materials is perhaps insufficient to support this agenda through poeisis and signification alone: many criticisms of this work focus on the way that kreidler’s presentation of himself as composer-as- author obscures engagement with the materials of the work in many of his projects, and this is perhaps supported by his insertion of himself into audioguide in his attempt to explain it. in order to reconcile these points, i return to the musically beautiful. the ‘beauty’ conceived of, at the opening of this discussion, as a radical facet of aesthetic experience, contrasted with a confirmation of tonal expectations, can be augmented with julia kristeva’s ( ) concept of abjection. for kristeva, the abject is an experience between the subject and the object ( , p. ). it ‘disturbs identity, system, order’, it ‘does not respect border, positions, rules’, and is ‘the in-between, the ambiguous, composite’ ( , p. ). aesthetic experience can be thought of as an abject experience. the ways that i have described it so far are indeed between the subject and the object, and do not require the recognition of an accepted symbolic order. the tension the ‘notenkraker’ group was a group of dutch composers who protested the lack of contemporary music programming in the netherlands. their name translates literally as ‘nut cracker’ but also has the sense of musical notes (noten) and of squatting (kraken; colloquial). the notenkrakersactie somewhat realised their aims which they had drawn attention to through disrupting orchestral and other performances at the concertgebouw in amsterdam. their work is comparable with the concept of protestaktionkunst. between learned behaviour and the real experience of the encounter with art is expressed by kristeva: ‘i abject myself with the same motion through which “i” claim to establish myself’ ( , p. ). so, the aesthetic experience - this experience of beauty, is one of alienation, abjection. this abjection is expressed by nono’s analysts who find his work impenetrable, even as they appear to penetrate it. nono’s rejection of a transparent compositional process is a rejection of the beautiful as the immediately comprehensible: he has composed an experience of alienation that has the esthesic effect of communicating a political message which perhaps cannot be otherwise meaningfully inscribed in music. conversely, kreidler’s rejection of autonomy is also an anti-aesthetic rejection of beauty: he favours comprehensibility. returning to adorno, kreidler’s work fulfills the ‘performance’ of the political that adorno finds in committed work, and there are many reasons to imagine this as a ‘pantomime’ when compared with nono. in contrast, nono’s work is the enactment of the longer-term political goals found in adorno’s ‘autonomous’ work. but the search for the musically beautiful perhaps makes this contrast the most stark: if the radical, alienating and abject elements of experience can be found in the esthesic dimension of the work, then criteria for politically successful aesthetics might also be identified on these terms. references adorno, t. ( ) commitment. frances mcdonagh trans. in aesthetics and politics. fredric jameson ed. london: verso. - . _____ ( ; ) the aging of the new music. in essays on music. richard leppert ed. susan h. gillespie trans. berkeley and los angeles: university of california press. agawu, k. ( ) tonality as a colonizing force in african music. princeton university. http://www.cirmmt.org/ activities/distinguished-lectures/agawu. accessed . . . bailey, k. ( ) “work in progress”: analysing luigi nono’s il canto sospeso. music analysis. . / . alexander goehr th birthday issue. - . eco, u. ( ) form as social commitment. the open work. anna cancogni trans. cambridge, ma: harvard university press., - . kreidler, j. ( ) audioguide. https://www.youtube.com/watch?v=s afutnficc. accessed . . . kristeva, j. ( ) powers of horror: an essay on abjection. leon s. roudiez trans. new york: colombia university press. lachemann, h. ( ) the beautiful in music today. tempo, new series. . - . mcclary, s. ( ) feminine endings: music, gender, & sexuality. minneapolis: university of minnesota press. morris, c. dir. ( ) nathan barley. channel [dvd] _____ ( ) nathan barley, fucking with your head yeah? channel . [insert]. nielinger, c. ( ) the song unsung: luigi nono’s “il canto sospeso”. journal of the royal musical association. v . . - . rancière, j. ( a) aesthetics and its discontents. steven corcoran trans. cambridge: polity. _____ ( b) the aesthetic unconscious. debra keates and james swenson trans. cambridge: polity. tommasini, a. ( . . ) music; the devil made him do it. new york times. http://www.nytimes.com/ / / /arts/music-the-devil-made-him-do-it.html. accessed . . . http 内部服务器出错 http 错误 http 内部服务器错误，请与管理员联系。请尝试以下操作： ·打开主页，然后查找指向您感兴趣信息的链接。 ·单击后退链接，尝试其他链接。错误：javax.servlet.servletexception: java.lang.numberformatexception: null 错误码：异常：null exception:javax.servlet.servletexception: java.lang.numberformatexception: null cause:java.lang.numberformatexception: null message:java.lang.numberformatexception: null localizedmessage:java.lang.numberformatexception: null stacktrace:javax.servlet.servletexception: java.lang.numberformatexception: null at org.apache.struts.action.requestprocessor.processexception(requestprocessor.java: ) at org.apache.struts.action.requestprocessor.processactionperform(requestprocessor.java: ) at org.apache.struts.action.requestprocessor.process(requestprocessor.java: ) at org.apache.struts.action.actionservlet.process(actionservlet.java: ) at org.apache.struts.action.actionservlet.doget(actionservlet.java: ) at javax.servlet.http.httpservlet.service(httpservlet.java: ) at javax.servlet.http.httpservlet.service(httpservlet.java: ) at org.apache.catalina.core.applicationfilterchain.internaldofilter(applicationfilterchain.java: ) at org.apache.catalina.core.applicationfilterchain.dofilter(applicationfilterchain.java: ) at org.apache.tomcat.websocket.server.wsfilter.dofilter(wsfilter.java: ) at org.apache.catalina.core.applicationfilterchain.internaldofilter(applicationfilterchain.java: ) at org.apache.catalina.core.applicationfilterchain.dofilter(applicationfilterchain.java: ) at org.apache.catalina.core.applicationdispatcher.invoke(applicationdispatcher.java: ) at org.apache.catalina.core.applicationdispatcher.processrequest(applicationdispatcher.java: ) at org.apache.catalina.core.applicationdispatcher.doforward(applicationdispatcher.java: ) at 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org.apache.catalina.core.applicationfilterchain.dofilter(applicationfilterchain.java: ) at org.apache.catalina.core.standardwrappervalve.invoke(standardwrappervalve.java: ) at org.apache.catalina.core.standardcontextvalve.invoke(standardcontextvalve.java: ) at org.apache.catalina.authenticator.authenticatorbase.invoke(authenticatorbase.java: ) at org.apache.catalina.core.standardhostvalve.invoke(standardhostvalve.java: ) at org.apache.catalina.valves.errorreportvalve.invoke(errorreportvalve.java: ) at org.apache.catalina.valves.remoteipvalve.invoke(remoteipvalve.java: ) at org.apache.catalina.valves.abstractaccesslogvalve.invoke(abstractaccesslogvalve.java: ) at org.apache.catalina.core.standardenginevalve.invoke(standardenginevalve.java: ) at org.apache.catalina.connector.coyoteadapter.service(coyoteadapter.java: ) at org.apache.coyote.http .abstracthttp processor.process(abstracthttp processor.java: ) at org.apache.coyote.abstractprotocol$abstractconnectionhandler.process(abstractprotocol.java: ) at org.apache.tomcat.util.net.nioendpoint$socketprocessor.dorun(nioendpoint.java: ) at org.apache.tomcat.util.net.nioendpoint$socketprocessor.run(nioendpoint.java: ) at java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java: ) at java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java: ) at org.apache.tomcat.util.threads.taskthread$wrappingrunnable.run(taskthread.java: ) at java.lang.thread.run(thread.java: ) caused by: java.lang.numberformatexception: null at java.lang.long.parselong(long.java: ) at java.lang.long.parselong(long.java: ) at com.wkxt.article.web.action.articledownloadfileenaction.execute(articledownloadfileenaction.java: ) at org.apache.struts.action.requestprocessor.processactionperform(requestprocessor.java: ) ... more small is again beautiful in description logics franz baader, carsten lutz, anni-yasmin turhan the description logic (dl) research of the last years was mainly concerned with increasing the expressive power of the employed description language without losing the ability of implementing highly-optimized reasoning systems that behave well in practice, inspite of the ever increasing worst-case complexity of the underlying inference problems. owl dl, the standard ontology language for the semantic web, is based on such an expressive dl for which reasoning is highly intractable. its sublanguage owl lite was intended to provide a tractable version of owl, but turned out to be only of a slightly lower worst-case complexity than owl dl. this and other reasons have led to the development of two new families of light-weight dls, el and dl-lite, which recently have been proposed as profiles of owl , the new version of the owl standard. in this paper, we give an introduction to these new logics, explaining the rationales behind their design. introduction description logics [ ] are a well-investigated family of logic- based knowledge representation formalisms, which can be used to represent the conceptual knowledge of an application domain in a structured and formally well-understood way. they are em- ployed in various application domains, such as natural language processing, configuration, and databases, but their most notable success so far is the adoption of the dl-based language owl as a standard ontology language for the semantic web [ , ]. in dls, concepts are formally described by concept descrip- tions, i.e., expressions that are built from concept names (unary predicates) and role names (binary predicates) using concept constructors. the expressivity of a particular dl is determined by which concept constructors are available in it. from a se- mantic point of view, concept names and concept descriptions represent sets of individuals, whereas roles represent binary rela- tions between individuals. for example, using the concept name woman, and the role name child, the concept of women having a daughter can be represented by the concept description woman u∃child.woman, and the concept of women having only daughters by woman u∀child.woman. in its simplest form, a dl terminology (usually called tbox ) can be used to introduce abbreviations for complex concept de- scriptions. for example, the concept definitions woman ≡ human u female mother ≡ woman u∃child.> define the concept of a woman as a human that is female, and the concept of a mother as a woman that has a child, where > stands for the top concept (which is interpreted as the universe of all individuals in the application domain). so-called general concept inclusions (gcis) can be used to state additional con- straints on the interpretation of concepts and roles. in our ex- ample, it makes sense to state domain and range restrictions for http://www.w .org/tr/owl-features/ the role child. the gcis ∃child.human v human human v ∀child.human respectively say that only human beings can have human chil- dren, and that the child of a human being must be human. in the assertional part (abox) of a dl knowledge base, facts about a specific application situation can be stated, by introduc- ing named individuals and relating them to concepts and roles. for example, the assertions woman(linda), child(linda, james) state that linda is a woman, who has the child james. knowledge representation systems based on dls provide their users with various inference services that allow them to deduce implicit knowledge from the explicitly represented knowl- edge. for instance, the subsumption service allows one to de- termine subconcept-superconcept relationships. for example, w.r.t. the concept definitions from above, the concept female subsumes the concept mother since all instances of the second concept are necessarily instances of the first concept, i.e., when- ever the above concept definitions are satisfied, then mother is interpreted as a subset of female. with the help of the sub- sumption service, one can compute the hierarchy of all concepts defined in a tbox. this compound inference service is usually called classification. the instance service can be used to check whether an individual occurring in an abox is necessarily an instance of a given concept. for example, w.r.t. the above as- sertions, concept definitions, and gcis, the individual james is an instance of the concept human. with the help of the instance service, one can also compute answers to instance queries, i.e., all individuals occurring in the abox that are instances of the query concept c. in order to state more general search criteria, one can use so-called conjunctive queries, i.e., conjunctions of assertions that may also contain variables, of which some can be existentially quantified. for example, the conjunctive query ∃y,z.woman(x) ∧ child(x,y) ∧ child(z,y) ∧ beatle(z) asks for all women that have a child with a parent that is a beatle. with respect to the knowledge base we have introduced so far, this conjunctive query has no individual as an answer. page in order to ensure a reasonable and predictable behavior of a dl system, the underlying inference problems (like the subsump- tion and the instance problem) should at least be decidable for the dl employed by the system, and preferably of low complex- ity. consequently, the expressive power of the dl in question must be restricted in an appropriate way. if the imposed re- strictions are too severe, however, then the important notions of the application domain can no longer be expressed. inves- tigating this trade-off between the expressivity of dls and the complexity of their inference problems has been one of the most important issues in dl research. the general opinion on the (worst-case) complexity that is acceptable for a dl has changed dramatically over time. histor- ically, in the early times of dl research people concentrated on identifying formalisms for which reasoning is tractable, i.e., can be performed in polynomial time [ ]. the precursor of all dl systems, kl-one [ ], as well as its early successor systems, like kandor [ ], k-rep [ ], back [ ], and loom [ ], indeed employed polynomial-time subsumption algorithms. later on, however, it turned out that subsumption in rather inexpressive dls may be intractable [ ], that subsumption in kl-one is even undecidable [ ], and that even for systems like kandor and back, for which the expressiveness of the underlying dl had been carefully restricted with the goal of retaining tractabil- ity, the subsumption problem is in fact intractable [ ]. the reason for the discrepancy between the complexity of the sub- sumption algorithms employed in the above mentioned early dl systems and the worst-case complexity of the subsumption prob- lems these algorithms were supposed to solve was due to the fact that these systems employed sound, but incomplete subsump- tion algorithms, i.e., algorithms whose positive answers to sub- sumption queries are correct, but whose negative answers may be incorrect. the use of incomplete algorithms has since then largely been abandoned in the dl community, mainly because of the problem that the behavior of the systems is no longer determined by the semantics of the description language: an in- complete algorithm may claim that a subsumption relationship does not hold, although it should hold according to the seman- tics. all the intractability results mentioned above already hold for subsumption between concept descriptions without a tbox. an even worse blow to the quest for a practically useful dl with a sound, complete, and polynomial-time subsumption algorithm was nebel’s result [ ] that subsumption w.r.t. an acyclic tbox (i.e., an unambiguous set of concept definitions without cyclic dependencies) in a dl with conjunction (u) and value restriction (∀r.c) is already intractable. at about the time when these (negative) complexity results were obtained, a new approach for solving inference problems in dls, such as the subsumption and the instance problem, was in- troduced. this so-called tableau-based approach was first intro- duced in the context of dls by schmidt-schauß and smolka [ ], though it had already been used for modal logics long before that [ ]. it has turned out that this approach can be used to handle a great variety of different dls [ , , , , , , , ], and it yields sound and complete inference algorithms also for very expressive dls. although the worst-case complexity of these al- all the systems mentioned above supported these two concept constructors, which were at that time viewed as being indispensable for a dl. the dl with exactly these two concept constructors is called fl [ ]. gorithms is quite high, the tableau-based approach nevertheless often yields practical procedures: optimized implementations of such procedures have turned out to behave quite well in appli- cations [ , , , , , ], even for expressive dls with a high worst-case complexity (exptime and beyond). the advent of efficient tableau-based algorithms was the main reason why the dl community basically abandoned the search for dls with tractable inference problems, and concentrated on the design of practical tableau-based algorithms for expressive dls. the most prominent modern dl systems, fact++ [ ], racer [ ], and pellet [ ] support very expressive dls and employ highly- optimized tableau-based algorithms. in addition to the fact that dls are equipped with a well- defined formal semantics, the availability of mature systems that support sound and complete reasoning in very expressive descrip- tion formalisms was an important argument in favor of using dls as the foundation of owl, the standard ontology language for the semantic web. in fact, owl dl is based on the expressive dl shoin(d), for which reasoning is nexptime-complete, and its sublanguage owl lite is based on shif(d), for which reasoning is still exptime-complete [ ]. the owl standard is based on the even more expressive dl sroiq(d), which is even nexptime-complete [ ]. due to the ever increasing expressive power and worst-case complexity of expressive dls, there is also an increasing number of ontologies emerging from practical applications that cannot be handled by tableau-based reasoning systems without manual tuning by the system developers, despite highly optimized im- plementations. perhaps the most prominent example is the well- known medical ontology snomed ct, which comprises , concepts and is used to generate a standardized health care ter- minology used as a standard for medical data exchange in a variety of countries such as the us, canada, and australia. in tests performed in with fact++ and racer, neither of the two systems could classify snomed ct [ ], and pellet still could not classify snomed ct in tests performed in [ ]. from the dl point of view, snomed ct is an acyclic tbox that contains only the concept constructors conjunction (u), existential restriction (∃r.c), and the top concept (>). the dl with exactly these three concept constructors is called el [ ]. in contrast to its counterpart with value restrictions, fl , the light-weight dl el has much better algorithmic properties. whereas subsumption without a tbox is polynomial in both el [ ] and fl [ ], subsumption in fl w.r.t. an acyclic tbox is conp-complete [ ] and w.r.t. gcis it is even exptime-complete [ ]. in contrast, subsumption in el stays tractable even w.r.t. gcis [ ], and this result is stable under the addition of several interesting means of expressivity [ , ]. the dl el and the mentioned tractability results will be introduced in more detail in the next section. another issue with expressive dls and tableau-based algo- rithms is that they do not scale too well to knowledge bases with a very large abox. in particular, query answering in expres- sive dls such as the already mentioned shif and shoin is exptime-complete regarding combined complexity [ ], i.e., the complexity w.r.t. the size of the tbox and the abox. thus http://www.ihtsdo.org/snomed-ct/ note, however, that more recent versions of fact++ and racer perform quite well on snomed ct [ ], due to optimizations specifi- cally tailored towards the classification of snomed ct. page name syntax semantics concept name a ai ⊆ ∆i role name r ri ⊆ ∆i × ∆i top concept > >i = ∆i conjunction c ud (c ud)i = ci ∩di existential restriction ∃r.c (∃r.c) i = {x | ∃y : (x,y) ∈ ri∧y ∈ ci} general concept inclusion (gci) c v d ci ⊆ di concept definition a ≡ c ai = ci table : syntax and semantics of el. query answering in these logics is even harder than subsumption while at the same time being much more time critical. moreover, query answering in these dls is conp-complete [ ] regarding data complexity (i.e., in the size of the abox), which is viewed as ‘unfeasible’ in the database community. these results are dramatic since many dl applications, such as those that use aboxes as kind of web repositories, involve aboxes with hun- dred of thousands of individuals. it is a commonly held opinion that, in order to achieve truly scalable query answering in the short term, it is essential to make use of conventional relational database systems for query answering in dls. given this pro- viso, the question is what expressivity can a dl offer such that queries can be answered using relational database technology while at the same time meaningful concepts can be specified in the tbox. as an answer to this, the dl-lite family has been introduced in [ , ], designed to allow the implementation of conjunctive query answering ‘on top of’ a relational database system. in section , we introduce dl-litecore and two of its extensions dl-litef and dl-liter. we also sketch the standard approach to query answering in these languages. interestingly, also in el it is possible to implement query answering using a database system, though with a different approach than in dl-lite (see the end of section ). the dl el and its extension el++ starting with a set ncon of concept names and a set nrole of role names, el-concept descriptions are built using the concept constructors top concept (>), conjunction (u), and existential restriction (∃r.c). the semantics of el-concept descriptions is defined in the usual way, using the notion of an interpretation i = (∆i, ·i), which consists of a non-empty domain ∆i and an interpretation function ·i that assigns binary relations on ∆i to role names and subsets of ∆i to concept descriptions, as shown in the semantics column of table . a general concept inclusion (gci) is of the form c v d where c,d are el-concept descriptions, and a concept defini- tion is of the form a ≡ c where a is a concept name and c is an el-concept description. the interpretation i is a model of the gci c v d or the concept definition a ≡ c if it satisfies the condition stated in the semantics column of table . obvi- ously, this semantics implies that the concept definition a ≡ c is equivalent to the two gcis a v c,c v a in the sense that they have the same models. for this reason, in the following we (r ) if a ua v b ∈t and a ,a ∈ s(a) then add b to s(a) (r ) if a v∃r.b ∈t and a ∈ s(a) then add r to r(a,b) (r ) if ∃r.b v a ∈t and b ∈ s(b),r ∈ s(a,b) then add a to s(a) figure : the completion rules for subsumption in el. will consider only gcis. a finite set of gcis is called a tbox. given a tbox t and two el-concept descriptions c,d, we say that c is subsumed by d w.r.t. t (written c vt d) if ci ⊆ di holds for all models i of t . when designing a subsumption algorithm for el it is actu- ally enough to consider the case where c,d are concept names occurring in the tbox. in fact, it is easy to see that c vt d iff a vt∪{avc,dvb} b where a,b are new concept names, i.e., concept names not occurring in c, d, and t . the polynomial-time subsumption algorithm for el [ , ] that will be sketched below actually classifies the given tbox t , i.e., it simultaneously computes all subsumption relationships between the concept names occurring in t . this algorithm proceeds in four steps: . normalize the tbox. . translate the normalized tbox into a graph. . complete the graph using completion rules. . read off the subsumption relationships from the normal- ized graph. an el-tbox is normalized iff it only contains gcis of the fol- lowing form: a u a v b,a v ∃r.b,∃r.a v b, where a,a ,a ,b are concept names or the top concept >. any el-tbox can be transformed in polynomial time into a normal- ized one by applying equivalence-preserving normalization rules [ ]. in the next step, we build the classification graph gt = (v,v ×v,s,r) where • v is the set of concept names (including >) occurring in the normalized tbox t ; • s labels nodes with sets of concept names (again includ- ing >); • r labels edges with sets of role names. the label sets are supposed to satisfy the following invariants : • b ∈ s(a) implies a vt b, i.e., s(a) contains only subsumers of a w.r.t. t . • r ∈ r(a,b) implies a vt ∃r.b, i.e., r(a,b) contains only roles r such that ∃r.b subsumes a w.r.t. t . initially, we set s(a) := {a,>} for all nodes a ∈ v , and r(a,b) := ∅ for all edges (a,b) ∈ v × v . obviously, the above invariants are satisfied by these initial label sets. the labels of nodes and edges are then extended by applying the rules of figure . note that a rule is only applied if it really extends a label set. it is easy to see that these rules preserve the above invariants. for example, consider the (most complicated) rule (r ). obviously, ∃r.b v a ∈ t implies ∃r.b vt a , and the assumption that the invariants are satisfied before apply- ing the rule yields b vt b and a vt ∃r.b. the subsumption in this section, we do not introduce aboxes and the instance problem. it should be noted, however, that the tractability results sketched in this section extend to the instance problem. page relationship b vt b obviously implies ∃r.b vt ∃r.b . by applying transitivity of the subsumption relation vt , we thus obtain a vt a . the fact that subsumption in el w.r.t. tboxes can be de- cided in polynomial time is an immediate consequence of the following two facts (see [ , ] for proofs): . rule application terminates after a polynomial number of steps. . if no more rules are applicable, then a vt b iff b ∈ s(a). theorem subsumption in el w.r.t. tboxes can be decided in polynomial time. this result is not only of theoretical interest. experiments have shown that an optimized implementation [ ] of the sub- sumption algorithm sketched above in the cel system [ ] behaves very well on large life science ontologies [ , ]. the tractability result for el can be extended to el++, which extends el by the following means of expressiveness: • the bottom concept ⊥ is always interpreted as the empty set. it can, for example, be used to express disjointness of concepts, as in the gci woman u man v⊥. • nominals are basically names for individuals, but used as concept constructors with set brackets around the individ- ual name. a nominal {n} is always interpreted as a single- ton set. for example, we can use the nominal {obama} to express the concept of all individuals that like obama: ∃likes.{obama}. nominals can also be used to express abox assertions through gcis. for example, the role as- sertion r(a,b) can be expressed as {a}v∃r.{b}. • concrete domains can be used to refer to data types like numbers or strings when defining concepts. for exam- ple, the concept description humanu≥ (age) describes adult human beings. however, only very restricted forms of concrete domains are admissible in el++ (see [ ] for details). • restricted role-value maps are of the form r ◦. . .◦rk v r. they are tbox axioms and not concept constructors. in a model of this role-value map, the composition of the roles r , . . . ,rk must be contained in the role r. special cases of such role-value maps are transitivity of a role r, ex- pressed as r◦r v r and right-identity rules r◦s v r, which are both important for medical ontologies. for example, we may want to say that the part of relation is transitive, which can be expressed as part of ◦ part of v part of, and that medical findings are inherited along part of, ex- pressed as finding at ◦ part of v finding at. given the second role-value maps together with gcis stating that a finger is part of the hand, an injury of the finger is an injury found at the finger, and an injury of the hand is an injury found at the hand, we can then deduce that an injury of the finger is an injury of the hand. • a reflexivity axiom for the role r states that this role is reflexive, i.e., every individual is related to itself w.r.t. this role. for example, in a medical ontology one may want to state that the part of relation is reflexive, i.e., every entity is part of itself. http://cel.googlecode.com • the range restriction ran(r) v c says that the second component of every tuple belonging to r must belong to c. for example, the range restriction ran(finding at) v body structure says that finding sites must belong to the body structure, i.e., this role is used to specify where in the body something (e.g., an injury) is found. the range restriction ran(r) v c could of course be expressed using the gci > v ∀r.c, but value restrictions ∀r.c are not available in el++. thus, range restrictions can be seen as a restricted way of using value restrictions in el++. note, however, that the unrestricted use of value restrictions would destroy tractability. note that the original version of el++ [ ] did not have reflex- ive roles and range restrictions. they were added in the version introduced in [ ], which is the version of el++ that underlies the designated owl el profile of owl . to keep tractability (even decidability), one must actually impose a syntactic re- striction on el++-tboxes that prevents interactions between restricted role-value maps and range restrictions (see [ ] for de- tails). it should also be noted that basically all other additions of typical dl constructors to el make subsumption w.r.t. tboxes exptime-hard [ , ]. the dl-lite family of dls dl-litecore is the basic member of the dl-lite family [ ]. con- cept descriptions of this dl are of the form a, ∃r.>, ∃r−.> where a is a concept name, r is a role name, and r− denotes the inverse of the role name r, with the obvious semantics (r − ) i = {(y,x) | (x,y) ∈ ri}. a dl-litecore knowledge base (kb) consists of a tbox and an abox. the tbox formalism allows for gcis and disjointness axioms between dl-litecore concept descriptions c,d: c v d and disj(c,d), where an interpretation i is a model of disj(c,d) if it satisfies ci ∩ di = ∅. although conjunction is not available in dl- litecore , it can be simulated to a certain extent: a conjunction on the right-hand side of a gci c v d ud can be expressed by the two gcis c v d and c v d . disjunction on the left-hand side of a gci can be expressed in a similar way. the following is an example of a dl-litecore -tbox: tex = {∃child.>v parent, parent v human, human v∃child−.>, disj(human, insect)}. a dl-litecore -abox is a finite set of concept and role assertions : a(a) and r(a,b), where a is a concept name, r is a role name, and a,b are individual names. an interpretation i assigns an element ci ∈ ∆i to every individual name c such that the unique name assumption (una) is satisfied, i.e. ai = bi for distinct individual names a,b. it is a model of a(a) if it satisfies ai ∈ the impact of dropping the una on the complexity of reasoning in the dl-lite family has been investigated in [ ]. page ai and of r(a,b) if it satisfies (ai,bi) ∈ ri. the restriction to concept names in concept assertions can be circumvented by introducing a gci for a new concept name, say anew v c, in the tbox and then stating anew(a) in the abox. the following is an example of a dl-litecore -abox: aex = {woman(linda), child(linda, james), beatle(paul), child(paul, james) }. in [ ], the following two extensions of dl-litecore have also been considered: • dl-litef, in which the tbox may additionally contain functionality axioms func(r) for role names and their in- verses. such an axiom can, e.g., be used to state that the role father is functional, i.e., every individual has at most one father. • dl-liter, in which the tbox may additionally contain role inclusion axioms r v r and role disjointness axioms disj(r ,r ) for role names and their inverses. such axioms can, e.g., be used to state that the roles father and mother are disjoint subroles of child−. other members of the dl-lite family have, e.g., been defined in [ , , ]. the dl-lite family of dls is tailored towards applications in which huge amounts of data (represented as an abox) are queried w.r.t. fairly light-weight ontologies. in this setting, it is no longer sufficient that query answering is tractable. one needs to be able to store the abox in a relational database system, and answer queries using a relational query engine. from a logical point of view, a relational database is a finite first-order interpretation i, and the relational query engine can efficiently answer first-order queries (fol queries). such a query is a first- order formula φ(~x) over the vocabulary of the database and with free variables ~x; an answer tuple ~c is a sequence of elements of the domain of i such that φ(~c) evaluates to true in i. given an fol query q, we denote the set of its answer tuples in the database i with qi. in dl-lite, one concentrates on answering a restricted form of fol queries, so-called unions of conjunctive queries. a con- junctive query is a conjunction of atoms, built using concept and role names as predicate symbols, individual names as con- stant symbols, and variables, of which some may be existentially quantified. for example, the following is a conjunctive query: qex = ∃y,z ,z . woman(x) ∧ child(x,y) ∧ child(z ,y) ∧ human(z ) ∧ child(z ,z ) a union of conjunctive queries is a finite set of conjunctive queries, which is interpreted as the disjunction of its elements. given a union of conjunctive queries or a conjunctive query q and a knowledge base k, the set of answers to q over k (denoted ans(q,k)) consists of all tuples ~a of individual names appearing in the knowledge base such that ~ai ∈ qi for every model i of the knowledge base. for the knowledge base kex = (tex,aex) of our example and the conjunctive query qex, it is easy to see that ans(qex,kex) = {linda}. the approach for query answering in dl-lite using a rela- tional database system proceeds as follows: . use the tbox t to reformulate the given union of con- junctive queries q into an fol query qt and then discard the tbox; . view the abox a as a relational database ia, which has as its domain all individuals names occurring in a, interprets concept names a as aia = {a | a(a) ∈ a}, and role names r as ria = {(a,b) | r(a,b) ∈a}; . evaluate qt in the database ia using a relational query engine. if this approach is correct for a given dl l, i.e., there is a re- formulation function q → qt such that qtia = ans(q, (t ,a)) for all unions of conjunctive queries q, then one says that an- swering conjunctive queries in l is fol-reducible. the following theorem is proved in [ ]. theorem answering conjunctive queries in dl-litecore , dl- litef, and dl-liter is fol-reducible. since the size of the reformulated query does not depend on the size of the abox, the data complexity of evaluating the original query (i.e., the complexity in terms of the size of the abox) is the same as evaluating the reformulated query. because the data complexity of evaluating fol queries in a relational database is complete for the complexity class ac , this implies that the data complexity of answering conjunctive queries in dl- litecore , dl-litef, and dl-liter is in ac , which is a proper subclass of the class of all tractable problems p . this method for query answering in dl-lite based on fol-reducibility has been implemented in the quonto system [ ]. the reformulation approach developed in [ ] actually yields a union of conjunctive queries rather than an arbitrary fol query. instead of describing it in detail, we illustrate it with our example. the main idea is to use the gcis in the tbox as rewrite rules from right to left. each rewrite step replaces an atom in a conjunctive query q contained in the union of conjunc- tive queries. the rewritten conjunctive query q′ is then added to the union of conjunctive queries (without removing the orig- inal query q). consider the atom child(z ,z ) in qex. since z is existentially quantified, this basically says that z belongs to ∃child−.>, and thus the gci human v ∃child−.> can be used to replace this atom with human(z ), which already occurs in the conjunctive query. thus, the new conjunctive query q( ): ∃y,z .woman(x) ∧ child(x,y) ∧ child(z ,y) ∧ human(z ) is added. in q( ), the atom human(z ) can be replaced by parent(z ), which yields the additional conjunctive query q ( ). using the gci ∃child.> v parent, the atom parent(z ) in q( ) can be replaced by child(z ,z ), where z is a new existentially quantified variable. this yields the new conjunctive query q( ): ∃y,z ,z .woman(x) ∧ child(x,y) ∧ child(z ,y) ∧ child(z ,z ) it is easy to see that linda is an answer for the query q( ) in the database iaex , and thus of the union of conjunctive queries generated by the reformulation process. in addition to rewriting atoms using gcis, the general reformulation process also uses unification of atoms in a conjunctive query to generate new conjunctive queries (see [ ] for details). it should be noted that also for (a fragment of) el++, an approach to conjunctive query answering using relational database systems has been developed [ , ]. since the data complexity of query answering in el is ptime-complete, the ap- proach follows a different route than the one for dl-lite (since fol-reducibility implies that the data complexity of query an- swering is in ac ). in particular, the tbox is incorporated into page the abox and not into the query. however, some limited query reformulation (independent of both the tbox and the abox) is still required. interestingly, both the abox rewriting and the query reformulation cause only a polynomial blow-up, in contrast to dl-lite, where the blow-up of the query may be exponential in the size of the original query [ ]. this alternative approach for query answering using a relational database system can also be applied to dl-lite [ ]. the approach introduced in [ ] causes an exponential blow-up of the query, but we believe that this may be avoidable. nevertheless, even with this blow-up the query execution times are typically smaller than those of the approach introduced in [ ]. conclusion we have described the origins of two novel families of light- weight dls: logics of the el family were designed to admit subsumption and classification in polynomial time, while still providing sufficient expressive power for life-science ontologies; logics of the dl-lite family have been designed to enable query answering using relational database systems, while still provid- ing sufficient expressive power to capture conceptual modelling formalisms. the relevance of the small dls discussed in this article is underlined by the fact that both of them are captured in the official w c profiles document for the candidate recom- mendation of owl . each of the owl profiles are designed for specific application requirements. for applications that rely on reasoning services for ontologies with a large number of con- cepts, the profile owl el has been introduced, which is based on el++. for applications that deal with large sets of data and that mainly use the reasoning service of query answering, the profile owl ql has been defined. the dl underlying this profile is dl-liter. both, the profile owl el and owl ql pave the way to apply very efficient reasoning services in practical applications. the recent research and 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[ ] d. tsarkov and i. horrocks. fact++ description logic reasoner: system description. in proc. of the int. joint conf. on autom. reasoning (ijcar’ ), lnai , . contact franz baader, anni-yasmin turhan institut für theoretische informatik tu dresden dresden email: [baader |turhan]@inf.tu-dresden.de carsten lutz universität bremen fachbereich postfach bremen email: clu@informatik.uni-bremen.de bild franz baader is director of the institute for theoretical computer science at tu dres- den. his main research areas are knowl- edge representation (in particular description and modal logics) and automated deduction (in particular term rewriting, unification, and combination of constraint solvers). bild carsten lutz is professor of computer sci- ence at the university of bremen. his re- search interests mainly concern applications of modal logic in computer science, including description logics, database formalisms such as xpath, and logics for automated verifica- tion. bild anni-yasmin turhan is teaching and re- search fellow at tu dresden. her research interests include reasoning in description logics, in particular non-standard inferences in dls and implementations of dl reasoning systems. page sleeping beauty gets specific by kai-jye lou, staff writer two international groups of researchers have expanded the utility of a transposon-based mutagenesis system, dubbed sleeping beauty, by adding tissue specificity to the system. they are now able to induce a wider range of cancers compared with the capacity of earlier itera- tions of the technology. , the increased reach of the technology has already allowed the groups to identify new disease-associated genes in hepatocellular carcinoma and colorectal cancer. the sleeping beauty transposon system contains two parts: a trans- posase enzyme and the transposon vector. in transgenic sleeping beauty model organisms, activation of the enzyme causes the transposon to induce traceable, random insertional muta- tions in host somatic cell genomes. the muta- tions can be identified with high throughput sequencing. earlier iterations of the technology employed a universal promoter for transposase expres- sion, which caused insertional mutations to occur in all tissues. mice generated using the original system primarily developed hematopoietic tumors and only a few solid tumor types such as soft-tissue sarcomas, pulmonary adenocarcinomas and malignant meningiomas. also, the inability to generate tumors in a tissue-specific manner made it dif- ficult to track the origins of a particular cancer cell. to overcome these shortcomings, overlapping research groups led by david largaespada integrated an additional element of control into the platform: a conditional, tissue-specific promoter that restricts sleeping beauty transposase expression. largaespada is leader of the genetic mechanisms of cancer research program at the university of minnesota’s masonic cancer center. in a paper in nature biotechnology, one group reported that they put transposase expression under the control of a hepatocyte-specific conditional promoter to induce hepatocellular carcinoma (hcc). in an article in science, the other group reported their use of a gastrointes- tinal epithelial cell–specific conditional promoter to induce colorectal cancer. each group of researchers then used a mouse genetics screen. the nature biotechnology team found genes and the science team found genes whose associations had not been previously reported in hcc and colorectal cancer, respectively. “results from these papers expand our understanding of the genes involved in colorectal and liver cancer, providing insight into the nature of these diseases and ultimately providing diagnostic and therapeutic tools,” said r. scott mcivor, a professor in the department of genetics, cell biology and development at the university of minnesota. mcivor is also ceo and cso at discovery genomics inc., which is developing the sleeping beauty system for use in human gene therapy. “the greater understanding of the group of genes contributing to colorectal and liver cancer will eventually lead to the development of improved therapies for these diseases,” he said. “the important thing here is that they’ve been able to limit the activity of the sleeping beauty transposon to specific organs and tis- sues,” said perry hackett, a professor in the university’s department of genetics, cell biology and development and who is the original developer of the sleeping beauty transposon system. “this conceptual breakthrough allows one to study a broader range of cancers, including slowly developing tumors,” hackett added. results from a previous paper by largaespada and a team at the national cancer institute showed that an earlier iteration of the sleep- ing beauty system caused mice to rapidly succumb to hematopoietic tumors before slow-growing solid tumors had the opportunity to develop. tissue-specific induction also makes it pos- sible to study the origins and progression of a cancer. “by limiting the tissue of origin where the transposase is activated, they are able to separate out original tumors from metastasis,” hackett told scibx. “in the nature biotechnol- ogy paper, they were able to show that tumors appearing in the lung originated from hcc cells in the liver.” “taken together, these results show that the sleeping beauty trans- poson system can be used as a generally applicable tool for identifying new targets for cancer treatment, detection and prognosis,” largaes- pada told scibx. “the sleeping beauty transposon system also can aid in the identification of major nodes in cancer pathways and provide insights on what combination therapies to use to target them.” anton berns, director of research at the netherlands cancer insti- tute, said the data generated from sleeping beauty–based insertional mutagenesis studies may help identify combinations of interdependent mutations, thus giving additional hints at which combinations of genes to target. more work ahead with the two proof-of-concept studies from largaespada’s group sup- porting use of the sleeping beauty system in cancer gene discovery, researchers contacted by scibx think the system will now be better positioned to complement other genomics systems and gene associa- tion studies. “transposons can only do certain things—they can only insert,” berns noted. transposons can activate or inactivate a gene as a result but are unable to induce point mutations, which are often seen in human tumors, he said. tools scibx: science–business exchange copyright © nature publishing group � “they were able to show that tumors appearing in the lung originated from hcc cells in the liver.” —perry hackett, university of minnesota http://www.scibx.com http://www .umn.edu/twincities/index.php http://www .umn.edu/twincities/index.php http://www.biocentury.com/companies/discovery_genomics_inc?utm_source= http://www.cancer.gov/ http://www.nki.nl/research/ http://www.nki.nl/research/ scibx: science–business exchange copyright © nature publishing group � tools for example, berns said, the sleeping beauty system cannot gener- ate activating point mutations in genes like ras, which are known to be strong drivers of cancer in humans. “there is a limit to the types of activating mutations that can be generated,” he concluded. berns said follow-up gene ablation or overexpression studies on the identified cancer-associated genes also will be needed to validate their roles in cancer. largaespada said his group is using sleeping beauty to identify additional cancer-associated genes and study other forms of the dis- ease, including brain and lung cancer. he added that he would also like to develop a sleeping beauty–based screening system to study cancer phenotypes and identify genes associated with metastasis, recurrence and drug resistance. largaespada told scibx that a patent covering the use of the sleeping beauty transposon system to identify cancer genes in laboratory animals is pending. the technology is available for licensing from the office for technology commercialization at the university of minnesota. lou, k.-j. scibx �( ); doi: . /scibx. . published online march , references . keng, v.w. et al. nat. biotechnol.; published online feb. , ; doi: . /nbt. contact: david largaespada, university of minnesota, minneapolis, minn. e-mail: larga @umn.edu . starr, t.k. et al. science; published online feb. , ; doi: . /science. contact: david largaespada, university of minnesota, minneapolis, minn. e-mail: larga @umn.edu contact: timothy k. starr, same affiliation as above e-mail: star @umn.edu . collier, l.s. et al. nature , – ( ) . ivics, z. et al. cell �, – ( ) . dupuy, a.j. et al. nature , – ( ) companies and institutions mentioned discovery genomics inc., minneapolis, minn. national cancer institute, bethesda, md. netherlands cancer institute, amsterdam, the netherlands university of minnesota, minneapolis, minn. mailto:larga @umn.edu mailto:larga @umn.edu mailto:star @umn.edu http://www.biocentury.com/companies/discovery_genomics_inc?utm_source= http://www.cancer.gov/ http://www.nki.nl/research/ http://www .umn.edu/twincities/index.php sleeping beauty gets specific more work ahead companies and institutions mentioned references cardiac fibroblasts: the good, the bad, the ugly, the beautiful ucla ucla previously published works title cardiac fibroblasts: the good, the bad, the ugly, the beautiful. permalink https://escholarship.org/uc/item/ bs w h authors sadoshima, junichi weiss, james n publication date - - doi . /j.yjmcc. . . peer reviewed escholarship.org powered by the california digital library university of california https://escholarship.org/uc/item/ bs w h https://escholarship.org http://www.cdlib.org/ journal of molecular and cellular cardiology ( ) contents lists available at sciencedirect journal of molecular and cellular cardiology journal homepage: www.elsevier.com/locate/yjmcc editorial cardiac fibroblasts: the good, the bad, the ugly, the beautiful this special issue is focused on the role of fibroblasts in cardiac biol- ogy. fibroblasts are the most numerous cells in the heart, and although their role in promoting fibrosis in the diseased heart has been recog- nized for more than years, it is only more recently that their active involvement in both normal cardiovascular biology and many other as- pects of cardiac pathophysiology besides fibrosis have been recognized. not only do fibroblasts play a key role in cardiac development, but once the heart has achieved its mature adult form, fibroblasts are the sentinel cells that are continuously reshaping the extracellular matrix to opti- mize the contractile function of the myocytes embedded within that matrix. fibroblasts are also the key player in scar formation when the heart is injured. this becomes the double-edged sword in heart disease – when the heart is injured, scar formation is essential to maintain the structural integrity of the heart walls and prevent rupture – however, scar formation also impairs contractile performance and makes the heart susceptible to arrhythmias. the therapeutic dream is to be able to direct cardiac repair in a way that maintains the heart's structural stability without impairing its electromechanical function. fibroblast biology will play a critical role in attempts to regenerate cardiac tissue using stem cell approaches, since fibroblasts will manufacture the extracellular matrix in which the regenerated myocytes reside. these are challenging issues, as the biology of cardiac fibroblasts is complex because they are comprised of heterogeneous populations of cells with distinct developmental origins which may dictate their basal functions as well as responses to stress. accordingly, the goal of this special issue is to provide a state-of-the- art update on fibroblast biology as it relates to the heart. we have invited a number of leading researchers in this field to share their views on diverse aspects of fibroblast biology, ranging from its roles in cardiac development, to maintaining the adult heart in a healthy state, to heart diseases, and finally, to the therapeutic potential for repairing diseased hearts. the articles are arranged roughly in this sequence, first focusing on the cell biology of fibroblasts and myofibroblasts in http://dx.doi.org/ . /j.yjmcc. . . - /© elsevier ltd. all rights reserved. the developing and adult heart, next reviewing their physiological roles as mechanosensors and modulators of cardiac electrophysiology via gap junction coupling, followed by their role in wound healing, aging, and cardiac pathologies including hypertrophy, ischemia, and ar- rhythmias. finally, the last two articles focus on the therapeutic poten- tial of modulating fibroblast biology. we are indebted to our scientific colleagues for their willingness to take the time and effort to share their thoughts about this exciting field with the scientific community, and especially for doing so in a timely manner. we are also very grateful to the editorial staff of the journal who made our role as the editors of this special issue a pleasure to undertake. conflict of interest none. junichi sadoshima department of cell biology and molecular medicine, rutgers new jersey medical school, south orange avenue, msb g , newark nj , usa tel.: + e-mail address: sadoshju@njms.rutgers.edu. james n. weiss division of cardiology, david geffen school of medicine at ucla mrl bldg c, young drive so., los angeles, ca , usa corresponding author. tel.: + . e-mail address: jweiss@mednet.ucla.edu. march http://crossmark.crossref.org/dialog/?doi= . /j.yjmcc. . . &domain=pdf http://www.sciencedirect.com/science/journal/ cardiac fibroblasts: the good, the bad, the ugly, the beautiful conflict of interest evo edu outreach ( ) : – doi . /s - - -z editorial endless forms most beautiful and most wonderful adam m. goldstein published online: february © springer science + business media, llc it has been a pleasure to serve as guest editor of this issue of evolution: education & outreach. editors- in-chief niles and greg eldredge and managing editor mick wycoff showed enormous support for my efforts to solicit and identify the highest quality submissions and to develop each to its potential. the professionals at springer made it easy for editors and authors alike to focus on scholarship. referees, drawn from an impressive pool of teachers and researchers across many disciplines, exemplified the dignity that is rightly accorded to the ideal of peer review as a safe- guard against bias and as a mechanism of the kind of cooperation and community input that is so important to the success of the scientific method. hooray for issue # ! the first issue of evolution: education & outreach has been a success. at the journal’s launch at the late november meeting of the national association of biology teachers, our editors quickly gave away more than , copies of issue # . the editorial staff will distribute free copies of the latest issue at many up- coming conferences of interest to our readers, such as the april meeting of the federation of societies of experimental biology. the journal’s success in print is a. m. goldstein (b) department of philosophy, iona college, north avenue, new rochelle, ny , usa e-mail: agoldstein@iona.edu url: http://iona.edu/faculty/agoldstein/ exceeded by its internet success. there have been more than , downloads from issue # ’s online electronic copy. visit the journal’s internet home at springer at http://www.springer.com/west/home/generic/search/ results?sgwid= - - - - for general journal information and a prominent link to digital copies of issues # and # , the entire contents of which are available online free of charge to anyone. alternatively, online content may be viewed directly at http://www.springerlink.com/content/ /. springer intends to offer the full contents of volumes and free online; depending upon the success of those volumes and funding support, the full contents of later volumes may also be offered online for free. our home page has not been the only frequent des- tination for our readers, who have made their presence known on the social networking web sites myspace.com and facebook.com. journal editors, contributors, and their colleagues post news items, photos, and links to related sites and other profiles in the myspace and facebook networks. as well, each evolution: education & outreach profile page hosts lively dis- cussion among community members, who also use the space to announce conferences, publications, in- ternships, and other groups and web sites likely to be of interest to our readers. myspace users are warmly invited to visit us at http://www.myspace.com/ springer_evoo, and facebook users should certainly make it a point to drop by http://facebook.com/ group.php?gid= (facebook users will be asked to log in to view the site, which requires a face- book account). visitors to either site are encouraged to add the journal’s profile as a friend (myspace) or join the group (facebook). http://www.springer.com/west/home/generic/search/results?sgwid= - - - - http://www.springer.com/west/home/generic/search/results?sgwid= - - - - http://www.springerlink.com/content/ / http://myspace.com http://facebook.com http://www.myspace.com/springer_evoo http://www.myspace.com/springer_evoo http://facebook.com/group.php?gid= http://facebook.com/group.php?gid= evo edu outreach ( ) : – an additional measure of our success is that there has been a sharp increase in the number of submis- sions. those wishing to contribute are encouraged to visit our editorial manager web site at https://www. editorialmanager.com/evoo/. contributions of all types are welcome, including research articles, personal reflections, reviews, and curriculum materials. reflections on this issue issue # presents a tough act to follow. nonetheless, i have confidence that all those who appreciated issue # will not be disappointed in the least with issue # , which delivers a similar mix of research, curriculum materials, essays, and reviews, all of which meet the high standard of excellence established in the previous issue. two characteristics of this issue of evolution: education & outreach are particularly striking: the broad approach of this issue’s contributors and the number of contribu- tions aimed at directing readers to quality information resources. a broad effort as is appropriate for the subject of evolution—whose theme is diversity and diversi- fication—the contributions to this issue take a wide range of approaches to a wide range of topics. for instance, niles eldredge, borsari, and thomson’s work concerns paleontology, whereas rybarczyk and jenkins address present-day evolutionary phenomena. taken as a group, these contributions treat evolution among higher taxa, molecular evolution, and within- population evolution of lineages of organisms—a variety of types of evolving entities and levels of evo- lution. the particular organisms treated by this issue’s authors fall across a range of taxa, including the aids virus, precambrian creatures near the roots of the tree of life, the mastodon, and—last but not least—human beings. some contributors approach evolution from perspectives outside science entirely. for example, richards takes the view of a historian and philoso- pher of science; borsari brings evolutionary themes into students’ sculpture and printmaking studios; mick wycoff reports on esther solondz’s installation de- picting important evolutionists; and depew describes the value to the classroom of inherit the wind. horenstein shows how new york building construc- tion, the history of dentistry and medicine, and the economics of museums can be used to focus attention on the evolution of the mastodon. my own contribution takes the form of a bibliographic essay. the take-home lesson here is that no one strategy or central insight provides the key to understanding evolution. evolution has far-reaching consequences for the natural world and for our understanding of our place in it; identifying and explaining those conse- quences requires all forms of human expression. a striking argument, the explanation of an adaptation or an evolutionary history, or an exemplary proof of the occurrence of evolution is useless to someone who lacks a proper context for it. i hope that future con- tributors to evolution: education & outreach provide pathways to understanding evolution as diverse as the contributors to the present issue have. the flood of information suppose that all informa- tion available online and in print concerning evolu- tion were correct. this would certainly be fortunate. nonetheless, even in this ideal situation, most questions about evolution would go unanswered: many correct information sources fail to inform because they lack relevance for the inquirer’s context. people seeking information do so for a particular purpose or with a particular inquiry in mind, and there is so much information available in the world’s libraries and on the internet—more and more, these two are becoming identical—that even experts cannot possibly consider a small fraction of the full range of sources that may be relevant to their questions. the idealization that all information available online and in print concerning evolution is correct is nowhere near being realized, so that the problem of information access is a serious one. this is what is meant by claiming that there is a flood of information about evolution. before beginning to identify the relevant sources among the good ones, a researcher must first eliminate those of no help to anyone. extending the diluvial metaphor, many of the con- tributions to this issue of evolution: education & outreach are aimed at damming the flood of informa- tion to create a reservoir of accurate and useful infor- mation resources. as he did in issue # , sid horenstein has put together our “in the news” section, pointing readers to news media sources about current events in evolutionary studies. in future issues, look for “in the news” to solicit news items from a wide range of sources among working evolutionists, focus on special topics from issue to issue, highlight web sites and other multimedia news sources, and offer critical appraisal of news coverage of evolutionary science. this issue also begins a regular section of book reviews. these include jenkins and fail’s reviews of https://www.editorialmanager.com/evoo/ https://www.editorialmanager.com/evoo/ evo edu outreach ( ) : – important works by jared diamond; finkelman’s reviews of some recent philosophical works about evolution; and hammond’s review of d. s. wilson’s evolution for everyone. future issues of evolution: education & outreach will offer an expanded reviews section, directing readers to quality internet and multi- media resources as well as books. this will supplement the reviews of museums, museum installations, and other cultural phenomena related to evolution that are already a part of evolution: education & outreach, as seen in whitson’s review in issue # of the american museum of natural history’s hall of human origins. endless forms most beautiful darwin concludes the origin of species eloquently: “from so simple a beginning, endless forms most beau- tiful and most wonderful have been, and are being, evolved.” i hope that from its beginnings in this first volume, evolution: education & outreach will continue to evolve forms most beautiful and wonderful: forms of argument and evidence; forms of access to information; and in general all forms of communication and expres- sion that will promote understanding of evolution and its consequences. endless forms most beautiful and most wonderful hooray for issue # ! reflections on this issue endless forms most beautiful a beautiful living thing ross birrell joanna crotch ‘let every artist strive to make his flower a beautiful living thing, something that will convince the world that there may be, there are, things more precious more beautiful - more lasting than life itself.’ c r mackintosh 'seemliness' (glasgow, ) on the rd may a fire spread through the glasgow school of art, charles rennie mackintosh’s masterpiece, badly damaging the heart of the school. the west wing of the building was particularly badly affected including several of the studios, professor’s offices, the hen run and sadly the library, considered to be the ‘jewel’ of mackintosh’s work, which incurred significant damage. the project in the immediate aftermath of the fire the response from the gsa’s students, staff and alumni was overwhelming. the sense of loss and sadness impacted on this community not just locally but also at an international level. this emotional reaction has, over the course of time, developed into a desire to engage with the mackintosh building, and a growing number of research projects focused on the building are now underway, involving students and staff. following this tragic event, birrell and crotch were both driven by a deep desire to record the irrevocable damage, and the concept of ‘a beautiful living thing’ developed. both authors independently felt a connection with the building in the context of their own research and through this common ground they agreed to collaborate on the project. the ambition was to capture and record the beauty within the building viewing the restoration of this damaged work of art from the immediate aftermath of the fire, and through the process of restoration to completion. through discussion the project developed and it was agreed that a series of three films would be produced; designed as a series of visual ‘movements’ each would be aligned to mark significant stages of rehabilitation of the building; before, during and after the restoration work. film places a single musician within the damaged library, and records a new composition transposed from the words of mackintosh ‘a beautiful living thing’. film will concern itself with ‘improvisation’ in response to the improvisatory nature of fire and will take place during the reconstruction phase. film will celebrate completion and a new beginning through a choral piece. it is hoped to invite gsa’s own choir to participate in this event. overall this is a linear project that has been conceived as a whole but with each part having independent legitimacy. the project team this collaborative project involves staff from within gsa and also has the ambition to extend its collaboration to artists from other creative institutions in the city. director ross birrell, an artist and lecturer at glasgow school of art (gsa), and producer joanna crotch, an architect and teacher at the mackintosh school of architecture also at the gsa, are the principles authors. they had not previously worked together before the fire but have found a connection through their own practices that brings their thinking together in the context of the mackintosh building, collaborating in the making of the filmic artefacts. they are supported by a core team of technicians from gsa who bring their own experience in film making to the project. it is also the authors’ aim that the project provides a platform for collaboration with other glasgow-based practitioners including rsno, glasgow improvisers orchestra, royal conservatoire and gsa choir. birrell’s previous work demonstrates a long-standing portfolio, which combines film, music and installations. he has become particularly fascinated with the relationship of music and place. his work includes site-specific compositions for the bomb- damaged spiegelsaal, claerchens ballhaus, berlin, the non-catholic cemetery rome and the burgkirche st. romanus, raron. this research has been widely exhibited internationally. crotch’s research explores embodied experience and memory, and this has resulted in a phenomenological approach to learning and teaching in the design of space and place. her teaching practice involves the creation of experiences that in turn become memories for the participants. working with a multi-disciplinary postgraduate group; these acoustical experiments use sound and music within specific site locations. the mackintosh building pre-fire has been one of the loci used for these events. these hands on workshops begin a discovery of ones understanding of environments through first hand experience. she has previously worked with rsno violinist chandler, exploring spatial experience via music and sounds. the research the primary objective of the research is to produce a sequence of films which respond through composed and improvised music and movement to the fire- damaged spaces of the mackintosh building and their subsequent reconstruction in such a way which recognise that the fire-damage has produced new compositional forms. for deleuze ‘art is composition’ and this premise both underpins and is challenged as the captured ‘movements’ address ‘composition’ and ‘improvisation’ in music and movement in response to both architecture (composition) and fire (improvisation). the primary research questions are ‘how might the fire-damaged mackintosh building be viewed as a composition?’ and ‘ how might music / movement register the emotional impact of the event of the fire and follow the paths of its reclamation and reconstruction?’ in light of these questions a methodology has been structured around composition and improvisation, which will respond to the contexts of composition (mackintosh building) and improvisation (fire) to produce new compositions and films. echoing the painstaking reclamation process, the camera will be used to record details of the interiors in ‘forensic’ close up, using slow movement, panning, steadicam and tracking shots, to collect these temporary compositions within the building. the focus is upon music and this further evolves birrell’s previous research into how musician responds to architectural spaces. this preoccupation continues through his compositions, which transpose context relevant text into scores that form the ‘soundtracks’ of his site-specific films. crotch’s experiential workshops with sound, including mackintosh library pre-fire, continue their concerns with site specificity and sound. part one the first ‘movement’ or film has now been completed. it explores the damage and debris resulting from the fire and features a composition by birrell, transposed and inspired by the words of mackintosh ‘a beautiful living thing’. bill chandler (rsno) performed the musical score in late december /early january inside the ruined library. captured on film, along with contextual shots to locate and record the status of the building then and there. at that time debris, now painstakingly removed by the archivists was still in location and provided a rich visual landscape, its multi-faceted surface also creating a unique temporary acoustical condition within the library. the resulting short film captures the atmosphere and spirit within the space through the performed music and captured visuals. it records the devastating impact of the fire on the library’s unique interior and its precious contents. beginning in silence in the first floor corridor in the west wing, the film takes the viewer slowly into the library, revealing an unworldly landscape of burnt fittings and fixture as well as badly charred books and furniture. here the lament begins with an overriding feeling of nostalgia, and a beauty and peace to the devastation is exposed, which creates an eerie and emotive atmosphere. the full physical volume of the library and the now exposed furniture store above is revealed as the camera pans back, exposing the catastrophic damage that has resulted from the fire. a single bearded sculpture of a musician with a violin in hand, stands guard aside the glassless towering windows, charred but resolute. the viewer is finally taken up to the loggia, and at this point the lament builds to a more hopeful tone, where views of the city are revealed in the last light of the day. throughout the movement the composition works with the canvas of city noise, resulting in a textural soundscape unique to that place at that time. part two the second movement is currently in the planning stage and it is envisaged that this will be complete by autumn . it will mark the completion of the decontamination process, which is currently underway, and also the commencement of the restoration contract. this second ‘movement’ intends to explore more closely the relationship of the passage of the fire through the building. unlike the first film, where the composition was created prior to the filming, this second phase will work with improvisation and this will represent a metaphor for the fire. a flow of movement and music will explore the studio and circulation spaces, using the mode of improvisation to weave paths and eddies within the spaces in an abstracted reflection of the nature of fire. performances will be by the glasgow improvisers orchestra, led by professor raymond macdonald, head of reid school of music, and edinburgh university. it is also intended to develop the theme of movement and improvisation with a glasgow based dance improvisation group, and negotiations with them are currently in progress. part three the concluding film will celebrate the completion of the restoration process. it is hoped that this will be developed in collaboration with the glasgow school of art’s choir, and is likely to be a celebratory coral composition. the date and precise venue for this final piece have yet to be determined. this on-going project has been fully supported and funded by the glasgow school of art’s research office and is part of a major programme of academic research aligned to the restoration of the mackintosh building. the first film has been well received having been screened at a number of events with gsa. its first public screening was in april , when it was screened as part of the programme for ‘building on the mac’ public symposium. the riba in london featured it within a special event to mark the end of its very successful ‘mackintosh architecture’ exhibition that showcased original drawings by mackintosh, at the end of may . other screenings have also been planned. a beautiful living thing is dedicated to the scottish fire & rescue services and the staff and students of the glasgow school of art. intelligence ( ) – why beautiful people are more intelligent satoshi kanazawa a,*, jody l. kovar b a interdisciplinary institute of management, london school of economics and political science, houghton street, london wc a ae, uk b department of sociology, indiana university of pennsylvania, usa received september ; received in revised form march ; accepted march available online june abstract empirical studies demonstrate that individuals perceive physically attractive others to be more intelligent than physically unattractive others. while most researchers dismiss this perception as a ‘‘bias’’ or ‘‘stereotype,’’ we contend that individuals have this perception because beautiful people indeed are more intelligent. the conclusion that beautiful people are more intelligent follows from four assumptions. ( ) men who are more intelligent are more likely to attain higher status than men who are less intelligent. ( ) higher-status men are more likely to mate with more beautiful women than lower-status men. ( ) intelligence is heritable. ( ) beauty is heritable. if all four assumptions are empirically true, then the conclusion that beautiful people are more intelligent is logically true, making it a proven theorem. we present empirical evidence for each of the four assumptions. while we concentrate on the relationship between beauty and intelligence in this paper, our evolutionary psychological explanation can account for a correlation between physical attractiveness and any other heritable trait that helps men attain higher status (such as aggression and social skills). d elsevier inc. all rights reserved. keywords: intelligence; physical attractiveness; stereotypes; correlation - /$ - see front matter d elsevier inc. all rights reserved. doi: . /j.intell. . . * corresponding author. tel.: + - - - . e-mail address: s.kanazawa@lse.ac.uk (s. kanazawa). if females generally prefer intelligent males because they typically have higher incomes and status, and if most males prefer physically attractive females, then over time these two characteristic will tend to covary. david m. buss ( , p. ). s. kanazawa, j.l. kovar / intelligence ( ) – . introduction in their article ‘‘beauty as status,’’ webster and driskell argue that physical attractiveness is a diffuse status characteristic, which affects others’ perceptions of competence. their experiment demonstrates that subjects perceive attractive others to be not only more intelligent and competent in general, but also more competent in such a seemingly unrelated and specific task as piloting a plane. while webster and driskell’s study leaves little doubt that physical attractiveness is a diffuse status characteristic which produces expectations of competence among perceivers, one important question remains unanswered: why is beauty status? why is physical attractiveness a diffused status character- istic and why does it produce the general and specific expectations of competence? there are other studies which demonstrate that people expect physically attractive others to be more intelligent than physically less attractive others (jackson, hunter, & hodge, ; zebrowitz, hall, murphy, & rhodes, ). studies also show that people perceive beautiful others to possess a host of other desirable qualities (eagly, ashmore, makhijani, & longo, ; feingold, ; langlois et al., ). this common perception is captured by the phrase ‘‘what is beautiful is good’’ (dion, berscheid, & walster, ). what is important to note, however, is that, for most of these studies, as it is for webster and driskell ( ), neither the sex of the target nor the sex of the perceiver has a significant effect on people’s perception that beautiful people are intelligent or otherwise good: both men and women perceive physically attractive men and women to be intelligent and good. in addition, children as young as first and second graders hold the perception that better looking teachers are more intelligent (goebel & cashen, ; zebrowitz et al., ). thus, romantic or sexual attraction does not seem to underlie people’s perception that beautiful others are intelligent and good (mulford, orbell, shatto, & stockard, ). while most researchers dismiss this perception as a ‘‘bias,’’ ‘‘stereotype,’’ or ‘‘halo effect’’ (with the implicit assumption that the perception is not accurate and has no factual basis) or else the outcome of self-fulfilling prophecy (snyder, tanke, & berscheid, ), we instead contend in this paper that people have this perception because more beautiful people indeed are more intelligent than less beautiful people. the conclusion that beautiful people are more intelligent follows from four assumptions. assumption . more intelligent men are more likely to occupy higher status than less intelligent men. assumption . higher-status men are more likely to mate with more beautiful women than lower- status men. assumption . intelligence is heritable, such that sons and daughters of more intelligent men are more intelligent than sons and daughters of less intelligent men. critics have noted that people have the opposite stereotype that extremely attractive women are unintelligent. we do not believe such a stereotype exists, however. we instead believe that the stereotype is that blonde women and women with large breasts are unintelligent, both of which, just like the stereotype that beautiful people are intelligent, may statistically be true. in the ancestral environment without any artificial means of altering appearance (such as hair dyes and plastic surgery), both light blonde hair (ridley , pp. – ) and large firm breasts (marlowe ) were honest indicators of youth, and thus naı̈veté and inexperience, which can sometimes be interpreted as a lack of intelligence. s. kanazawa, j.l. kovar / intelligence ( ) – assumption . beauty is heritable, such that sons and daughters of more beautiful women are more beautiful than sons and daughters of less beautiful women. the conclusion that more beautiful people are more intelligent than less beautiful people logically follows from these four assumptions, making it a theorem. in other words, if all four assumptions are empirically true, then the conclusion must logically be true and there must be a correlation between beauty and intelligence. such a correlation, however, is extrinsic, rather than intrinsic (jensen, , pp. – ) or causal. our contentions in this paper are therefore twofold: ( ) there exists an empirical correlation between beauty and intelligence across individuals and ( ) this correlation is extrinsic and results from assortative mating of intelligent, high-status men and beautiful women. whereas zebrowitz et al. ( ) consider and rule out one evolutionary psychological explanation for the covariance of beauty and intelligence (whereby ‘‘good genes’’ produce both beauty and intelligence), we offer an alternative evolutionary psychological explanation whereby such covariance is extrinsic (not causal) and occurs as a result of assortative mating. this possibility was originally suggested very briefly by vandenberg ( ), and again by buss ( ) in the passage quoted above. our paper formalizes their insight and presents a deductive theory of this process with supportive empirical evidence for each of the assumptions necessary to derive the theorem. before we turn to the evidence, however, we will briefly discuss the key concept of physical attractiveness. . physical attractiveness (beauty) while theory and research in evolutionary psychology usually confirm, and elucidate the mechanisms behind, most stereotypes, common perceptions and aphorisms, such as ‘‘men like young and attractive women, and women like rich and powerful men’’ (buss, ), they have disconfirmed two aphorisms about beauty: ‘‘beauty is in the eye of the beholder’’ and ‘‘beauty is skin deep.’’ evolutionary psychology has shown neither to be entirely true (langlois et al., ). . . beauty is not entirely in the eye of the beholder samuels and ewy ( ) and langlois et al. ( ) were the first to demonstrate that the standards of beauty might be at least partly innate. in their experiments, infants as young as and months gaze longer at a face that adults have judged to be more attractive than at a face that adults have judged to be unattractive, indicating the infants’ preference for attractive faces. langlois, roggman, and reiser- danner ( ) show that -month-old infants exhibit more observable pleasure, more play involve- ment, less distress, and less withdrawal when interacting with strangers wearing attractive masks than when interacting with strangers wearing unattractive masks. they also play significantly longer with facially attractive dolls than with unattractive dolls. because – months is not nearly enough time for infants to have learned and internalized the cultural standards of beauty through socialization and media exposure, the evidence by langlois et al. seems to suggest that the standards of beauty might be innate, not learned. because the standards of beauty are innate, they are also culturally universal and invariant, contrary to popular belief (cunningham, druen, & barbee, ). within the united states, asians and whites s. kanazawa, j.l. kovar / intelligence ( ) – (wagatsuma & kleinke, ), and whites and blacks (bernstein, lin, & mcclellan, ; cross & cross, ) agree on which faces are more or less attractive. cross-culturally, there is considerable agreement in the judgment of beauty among asians, hispanics, and americans (cunningham, roberts, barbee, druen, & wu, ), brazilians, americans, russians, the ache of paraguay, and the hiwi of venezuela (jones & hill, ; jones, ), cruzans and americans in st. croix (maret & harling, ), white south africans and americans (morse & gruzen, ), and the chinese, indians, and english (thakerar & iwawaki, ). in none of these studies does the degree of exposure to the western media have any influence on people’s perception of beauty. rather than arbitrary, culturally specific, learned, and idiosyncratic (implicit in the phrase ‘‘beauty is in the eye of the beholder’’), the standards of beauty appear to be innate, culturally universal, and part of evolved psychological mechanisms or adaptations (hence the new aphorism ‘‘beauty is in the adaptations of the beholder’’; symons, ). the standards of beauty appear to be part of universal human nature. but why should this be so? why should all humans consider some facial features more attractive than others? and what facial features do we consider attractive? . . beauty is not entirely skin deep evolutionary psychological research suggests that the standards of beauty might be species-typical because attractive people are genuinely different from less attractive people. specifically, beauty is an indicator of genetic and developmental health. there is some evidence that physically attractive people are healthier than physically less attractive people (langlois et al., ; shackelford & larsen, ; but see kalick, zebrowitz, langlois, & johnson, for counterevidence). there appear to be a few features that characterize physically attractive faces: bilateral symmetry, averageness, and secondary sexual characteristics (little, penton-voak, burt, & perrett, ). attractive faces are more symmetrical than unattractive faces (gangestad, thornhill, & yeo, ; mealey, bridgstock, & townsend, ; perrett et al., ). fluctuating asymmetry (fa) increases with exposure to parasites, pathogens, and toxins during development (bailit, workman, niswander, & maclean, ; møller, , ; parsons, ). fa also increases with genetic disruptions, such as mutations and inbreeding (parsons, ). developmentally and genetically healthy individuals have less fa, more symmetry in their facial and bodily features, and are more attractive. for this reason, across societies, there is a positive correlation between parasite and pathogen prevalence in the environment and the importance placed on physical attractiveness in mate selection (gangestad & buss, ); people place more importance on physical attractiveness when there are more pathogens and parasites in their local ecology. this is because, in societies where there are a lot of pathogens and parasites in the environment, it is especially important to avoid individuals who have been afflicted with them when they select mates. facial averageness is another feature that increases physical attractiveness; faces with features closer to the population average are more attractive than those with extreme features (langlois & roggman, ; rubenstein, langlois, & roggman ). evolutionary reasons for why average faces in the population are more attractive than extreme faces are not as clear as the reasons for why facial symmetry is attractive. current speculation is that facial averageness results from the heterogeneity rather than homogeneity of genes, and thus individuals with average faces are more resistant to a larger number of parasites and are less likely to be homozygous on deleterious alleles (thornhill & gangestad, ). thus, just like fa, facial averageness may be an indicator of genetic health and parasite resistance. s. kanazawa, j.l. kovar / intelligence ( ) – far from merely skin deep, beauty appears to be an indicator of genetic and developmental health, and therefore of mate quality; beauty is a ‘‘health certification’’ (thornhill & møller, , pp. – ). fa measures beauty so accurately that there is now a computer program which can calculate someone’s level of fa from a scanned photograph of a face (by measuring the sizes of, and distances between, various facial parts) and assign a single score for physical attractiveness, which correlates highly with scores assigned by human judges (grammer & thornhill, ). a computer program can also digitally average human faces (langlois, roggman, & musselman, ). beauty therefore appears to be an objective and quantitative attribute of individuals like height and weight. . using the current architecture of the brain to make inferences about the ancestral environment evolutionary psychologists contend that the human brain (like the rest of the body) is adapted, not necessarily to the current environment, but to the ancestral environment in which we evolved. the way our mind functions, the way we perceive or ‘‘see’’ things, often reflects how things were in the ancestral environment. stereotypes or common perceptions, to the extent that they are universally shared, seem to be no exceptions. for instance, one of the stereotypes that people have is that high-status people are taller. in one experiment (dannenmaier & thumin, ), freshmen in a nursing school estimated the height of four people they knew well who differed in their status (assistant director of the school, instructor at the school, their class president, and one specific fellow student). the students consistently overestimated the height of two high-status people (assistant director and instructor), and underestimated the height of two low-status people (class president and fellow student). in another experiment (wilson, ), the same man was introduced to five different groups of students. in each group, he was introduced as someone with a different academic status (student, demonstrator, lecturer, senior lecturer, and professor). after the man left the room, the students were asked to estimate his height. the status of the stimulus person had a positive and monotonic effect on his estimated height. participants who thought he was a student estimated him to be less than ft in.; those who thought he was a professor estimated him to be more than ft. why is this? why do people perceive higher-status persons to be taller than lower-status persons? it may be because higher-status persons tended to be taller than lower-status people throughout the evolutionary history. in the ancestral environment, many (if not most) competitions for status were physical, although alliances and coalitions were also important (de waal, ). our ancestors physically fought each other, and those who won the physical battle came out on top to occupy high status. in the ancestral environment, taller and bigger people therefore had an advantage over shorter, smaller competitors, and they often occupied high status. in fact, a positive correlation between height and status still exists today to a lesser extent. across all species, there is a significant positive correlation between height or body size and status dominance (ellis, ); taller or larger males in these species are more likely to be dominant in social hierarchies than smaller males. in human villages throughout the world, the chief is known as ‘‘the big man,’’ and they are usually tall. the average height of men in the united states today is ft in. yet more than half of the ceos of the fortune companies are ft or taller; only % are ft in. or less (etcoff, , p. ). since , only two u.s. presidents (james madison and benjamin harrison) have been below average in height, and the taller candidate almost always wins the presidential election (mcginniss, ). s. kanazawa, j.l. kovar / intelligence ( ) – our stereotype that higher-status people are taller thus accurately reflects how things tended to be in the ancestral environment and, to a lesser extent, how things still tend to be in the current environment. we contend that our perception that beautiful people are more intelligent has a similar origin. individuals believe that more attractive people are more intelligent today, because such a correlation existed in the ancestral environment, and may have survived to the current environment (like the correlation between height and status). . a note on parsimony our theory posits four assumptions (assumption : more intelligent men are more likely to occupy higher status than less intelligent men; assumption : higher-status men are more likely to mate with more beautiful women than lower-status men; assumption : intelligence is heritable; and assumption : beauty is heritable) in order to deduce a theorem (theorem : more beautiful people are more intelligent). we posit these four assumptions, and none other, because these constitute the minimal set of assumptions necessary and sufficient to derive the theorem. we leave out a large number of related observations from our theory because they are not necessary. in particular, our theory does not state: (a) beauty increases men’s status; (b) intelligence increases women’s status; (c) children inherit their beauty from their father; or (d) children inherit their intelligence from their mother. we do not posit these assumptions, not because we believe they are not true, but because they are not necessary for the logical derivation of the theorem. in fact, we do believe all four of these observations are true, and there is empirical evidence to support each of them. however, to the extent that they are true, these unstated assumptions strengthen, rather than weaken, the extrinsic correlation between beauty and intelligence. for instance, once there is a correlation between beauty and intelligence (as a result of the assortative mating that our theory posits), then more intelligent men are more likely to be beautiful than less intelligent men, and more beautiful women are more likely to be intelligent than less beautiful women. then, if intelligence is heritable from the mother to her children (in addition to the father), and if beauty is heritable from the father to his children (in addition to the mother), the extrinsic correlation between beauty and intelligence among the children will be even stronger than if intelligence is heritable only through the father and beauty is heritable only through the mother (as our theory states). deductive theory like ours is not a comprehensive description of the complex reality and therefore by necessity leaves out much that is true (kanazawa, ). however, scientific theory should not be evaluated by how much it does not say or whether what it does not say is true, but rather by whether what it does say is true. . empirical evidence for the assumptions and the theorem . . assumption . more intelligent men are more likely to occupy higher status than less intelligent men by intelligence, we mean what psychometricians call general intelligence or the g factor (spearman, ). general intelligence is an important determinant of success in a wide range of endeavors s. kanazawa, j.l. kovar / intelligence ( ) – (gottfredson, ). ‘‘the g factor... predicts performance to some degree in every kind of behavior that calls for learning, decision, and judgment...because g is intrinsic to learning novel material, grasping concepts, distinctions, and meanings’’ (jensen, , p. ). there is evidence that men who occupy higher-status positions are more intelligent. across different occupations, the correlation between occupational prestige (a measure of status) and the mean iq of individuals in the occupation is between . and . , although the correlation between occupational prestige and individual iq across individuals is only about . to . due to the large variance in intelligence among individuals in any given occupation (jensen, , pp. – ). there is a significant positive correlation between the mean iq and the occupational prestige among both the draftees of world war i (fryer, ) and those of world war ii (harrell & harrell, ). the data from the u.s. department of labor show the following mean iqs for selected occupations: engineer ( ), accountant ( ), teacher ( ), bookkeeper ( ), photographer ( ), stenographer ( ), machinist ( ), carpenter ( ), laborer ( ), and stock clerk ( ). men who scored above the th percentile on the armed forces qualification test after the korean war had incomes % above the national mean, and those who scored below the th percentile had incomes % below the mean (jencks, , pp. – ). the former group of men earned twice as much as the latter. reynolds, chastain, kaufman, and mclean’s ( ) more comprehensive study (n = ) also demonstrates a monotonic positive relationship between occupational prestige and mean iq: professional and technical ( . ), managerial, clerical and sales ( . ), skilled workers ( . ), semiskilled workers ( . ), and unskilled workers ( . ). iq also has a significant (p < . ) main effect on educational attainment. longitudinal data demonstrate that the direction of causation is from intelligence to occupational prestige, not the other way around. ball ( ) shows that childhood iqs of men correlate significantly with their adult occupational prestige—at . , fourteen years later and at . , nineteen years later. thorndike and hagen ( ) study , world war ii airforce cadets, all of whom were high- school graduates and had iqs above . their iqs were measured at age , and their occupational prestige at age . those who were . standard deviations above the mean iq of had occupations, such as accountants, architects, college professors, engineers, lawyers, physicians, scientists, treasurers and comptrollers, and writers. those who were . standard deviations below the mean became bus and truck drivers, guards, miners, production assemblers, tractor and crane operators, railroad trainmen, and welders. despite the limited variance in iq ( % of the total variance in the general population), there is a positive correlation between iq and occupational prestige among the men studied by thorndike and hagen. terman and oden’s ( ) study of gifted children, all with iqs above (m = ) reaches the same conclusion. over % of the men in their study were in the following occupations as adults: lawyers, engineers, college professors, major business managers, financial executives, scientists, physicians, educational administrators, top business executives, and accountants. only % of these men were farmers or semiskilled laborers, and virtually none were unskilled laborers. in their longitudinal study of , th graders, austin and hanisch ( ) conclude that general mental ability is the strongest predictor of their occupational attainment years later. hunter and hunter’s ( ) meta-analysis reaches a similar conclusion that mental ability is the strongest predictor of job performance for entry-level jobs. the effect of intelligence on status is also evident in the study of intergenerational mobility. in minnesota, waller ( ) discovers that sons whose iqs were higher than their fathers’ tended to be s. kanazawa, j.l. kovar / intelligence ( ) – upwardly mobile, while those whose iqs were lower than their fathers’ tended to be downwardly mobile. furthermore, the more discrepant the son’s iq was from his father’s in either direction, the more likely the son was to be upwardly or downwardly mobile. in england, mascie-taylor and gibson ( ) find that the iqs of upwardly mobile sons averaged seven points higher than those of their fathers, whereas those of downwardly mobile sons averaged eight points lower. intelligence also predicts job perfor- mance. within a single occupation, workers with higher intelligence scores are better workers, on the basis of both supervisors’ evaluations and objective measures of productivity (ghiselli, ; hunter, ). the cognitive ability is highly correlated (r=. ) with job performance in civilian jobs (hunter, ). men with higher iqs are therefore more upwardly mobile both within and across generations. there appears to be little doubt that more intelligent men are more likely to occupy higher status than less intelligent men. . . assumption . higher-status men are more likely to mate with more beautiful women than lower- status men from the evolutionary psychological perspective, there are theoretical reasons to expect that higher- status men and beautiful women marry each other. buss’ ( ) extensive cross-cultural data on criteria of mate selection indicate that men in all cultures prefer physically attractive women as their mates, and women in all cultures prefer wealthy men of high status as their mates. there have also been experimental demonstrations that men prefer to mate with physically attractive women and women prefer to mate with socially dominant men (graziano, jensen-campbell, todd, & finch, ; gutierres, kenrick, & partch, ; kenrick, neuberg, zierk, & krones, ). because not every man can marry a beautiful woman, and not every woman can marry a wealthy man of high status (even in polygynous societies), it is natural to assume that more desirable (i.e., higher-status) men will marry more desirable (i.e., beautiful) women. the process of assortative mating should unite higher-status men and physically attractive women in mateships. available empirical studies demonstrate that this may be the case. in his study of intermarriage in india, davis ( ) notes that, while strict caste endogamy is the rule, certain types of hypergamy (where women from lower castes marry men from higher castes) are culturally sanctioned. when this happens, the women are always physically attractive. in a longitudinal study of youths from oakland, ca (elder, ), women’s physical attractiveness has a very strong (. ) effect on their husband’s occupational status in the path analysis. the bivariate correlation between women’s physical attractiveness with their husband’s occupational status is stronger among working-class women (. ) than among middle-class women (. ). among the working-class women, their physical attractiveness is the strongest determinant of their husband’s occupational status. in their analysis of large, nationally representative data ( cps-src american election study), taylor and glenn ( ) find that the correlation between women’s physical attractiveness and their husband’s occupational status is significantly positive (. , p < . ), and does not vary by the woman’s age. consistent with elder ( ), taylor and glenn ( ) find that the effect of physical attractiveness on the husband’s occupational status is strongest among women from working-class families. in his replication of elder ( ) and taylor and glenn ( ), udry ( ) demonstrates that, among both blacks and whites, upwardly mobile women are more physically attractive than others. women’s physical attractiveness has a significant effect on both their husband’s occupational status, and s. kanazawa, j.l. kovar / intelligence ( ) – their upward mobility (the difference between their father’s and husband’s occupational statuses). in their analysis of longitudinal data on a national sample of high-school sophomores originally surveyed in , udry and eckland ( ) find that women’s physical attractiveness has a significantly positive effect on their household income, although it has no effect on their own income (among those who were employed in ). udry and eckland interpret this ‘‘as evidence that females’ attractiveness affects adult status through marriage to husbands of high income’’ (p. ). more attractive women in their sample marry men with more education as well. finally, hamermesh and biddle’s ( ) analysis of the quality of employment survey finds that, relative to average-looking women, below-average- looking women are married to men with significantly less education, concurring with udry and eckland’s findings. available evidence thus indicates that there is assortative mating between high- status men and physically attractive women. . . assumption . intelligence is heritable there is insurmountable evidence that general intelligence (g) is substantially genetically heritable. behavior geneticists currently estimate the genetic heritability (h ) of g to be somewhere between . and . (bouchard, lykken, mcgue, segal, & tellegen, ; bouchard & mcgue, ; pedersen, plomin, nesselroade, & mcclearn, ; plomin & defries, ). genetic heritability between . and . , however, means that – % of the variance in general intelligence is environmental. the current research in behavior genetics indicates that most of these environmental influences largely occur outside of the family, in what behavior geneticists call nonshared environment (e ; harris, ; rowe, ). because most of the environmental effects on general intelligence take place outside of the family, through processes that do not involve the parents, these environmental factors tend to attenuate the correlation in g between parents and children. the current estimate of the bivariate correlation (r) between parents’ and children’s general intelligence, derived from studies involving pairs of parents and children, is . (p < . ; fig. cited in bouchard & mcgue, ). consistent with the earlier evidence in behavior genetics, a study of preschoolers in china (wang & oakland, ) confirms that general intelligence is largely heritable. children aged – years whose parents are either intelligentsia (e.g., teachers or doctors) or officers (e.g. managers) have significantly (p < . ) higher iqs than their agemates whose parents are either clerks or workers. the parents’ education also has a monotonic positive effect on their children’s iqs. those whose parents have a college or university education have significantly (p < . ) higher iqs than those whose parents have a senior high-school education, who in turn have significantly (p < . ) higher iqs than those whose parents only have junior high-school education. available empirical evidence in behavior genetics and elsewhere therefore indicates that general intelligence is heritable. . . assumption . beauty is heritable perhaps the idea that offspring physically resemble their parents, and thus beautiful parents beget beautiful children, is too obvious and taken for granted to be subjected to empirical verification in scientific research. we have not been able to locate any empirical study whose principal goal is to establish the heritability of physical attractiveness. however, a few studies on other topics have computed correlations in physical attractiveness between monozygotic (mz) twins and dizygotic s. kanazawa, j.l. kovar / intelligence ( ) – (dz) twins. we are able to estimate the heritability coefficient (h ) of physical attractiveness from these correlations. mcgovern, neale, and kendler ( ) show that the correlation in physical attractiveness between female mz twins (n = pairs) is . , and for female dz twins (n = pairs), it is . . because h = (rmz � rdz), their data show that the heritability coefficient for physical attractiveness is . . rowe, clapp, and wallis ( ) measure the physical attractiveness of mz twins ( male and female pairs). because their final sample does not contain dz twins, they are not able to estimate heritability (h ) of physical attractiveness from their data as do mcgovern et al. however, the uncorrected correlation in physical attractiveness among the mz twin pairs is r=. , and rowe et al. estimate the ‘‘true’’ correlation, corrected for measurement errors, to be r=. , which seems to suggest a very high h . these available estimates therefore show that physical attractiveness is probably as highly heritable as intelligence is (see section . ). there is also some indirect evidence that beauty is heritable. as we note above, beautiful faces are symmetrical faces that indicate underlying genetic and developmental health; fa and other measures of developmental stability underlie beauty (thornhill & møller, , pp. – ). livshits and kobylianski’s ( ) study of two samples of nuclear families in israel (ns = and ) indicates that the heritability of mean fa (calculated from eight different bilateral traits) is . . møller and thornhill’s ( ) meta-analysis shows that the overall mean effect size of heritabilities of individual fa, computed from studies of species, is . (p < . ). these studies indicate that there is a significant genetic component to developmental stability and fa, and hence to beauty. fa is heritable, hormone markers in the face are heritable, and facial structure in general is heritable. it is therefore reasonable to assume that physical attractiveness is also heritable, as available evidence indicates. . . theorem . more beautiful people are more intelligent if assumptions – are empirically true, then theorem is logically true. however, there is also empirical evidence to support the claim that beautiful people are more intelligent. elder ( ) notes that middle-class girls in his longitudinal sample simultaneously have higher iqs (p < . ) and are physically more attractive (p < . or p < . ) than working-class girls. his data therefore indicate that intelligence and beauty might be positively correlated among his female respondents. zebrowitz et al.’s ( ) analysis of longitudinal data from the intergenerational studies of development and aging demonstrates that facial attractiveness significantly (p < . , p < . , or p < . ) correlates with iq among both men and women throughout the life course (childhood, puberty, adolescence, and middle adulthood), except late adulthood. furlow, armijo-prewitt, gangestad, and thornhill ( ) find that body fa is significantly negatively correlated with psychometric intelligence (iq) among two separate samples of under- graduates. physical attractiveness (inversely measured by fa) is therefore positively correlated with intelligence in their samples. jackson et al.’s ( ) and langlois et al.’s ( ) comprehensive meta-analyses demonstrate that more beautiful children and adults of both sexes have greater intelligence. langlois et al. thus conclude that the maxim ‘‘beauty is skin deep’’ is a ‘‘myth.’’ at the same time, however, their meta-analysis also shows that the relationship between beauty and intelligence, while statistically significant (p < . ), is nonetheless very weak (weighed d=. ), compared to the relationship between beauty and popularity (d=. ) or perception of occupational s. kanazawa, j.l. kovar / intelligence ( ) – competence (d=. ). thus, their meta-analysis also seems to demonstrate that beauty is at least partially skin deep while at the same time, partially more than skin deep. there are other studies that indirectly demonstrate that beautiful people are more intelligent. these studies typically use some measures of attainment (like income or education) as indicators of intelligence. of course, to use these studies to support theorem , we must assume that assumption (intelligence leads to high status) holds true for both men and women. mazur, mazur, and keating ( ) show that, among west point cadets, physical attractiveness (measured by facial dominance) has a significant positive effect on their cadet rank while at west point. umberson and hughes ( ) show that, controlling for demographic variables, physical attractiveness has a significant positive effect on family income (p < . ), personal income (p < . ), duncan sei (p < . ), and education (p < . ) in a large (n = ) representative sample in the united states. in their study, the effect of physical attractiveness interacts with neither race nor sex of the respondent; beauty is positively correlated with intelligence among both men and women of all races. in their analysis of a sample of canadians employed full-time (n = ), roszell, kennedy and grabb ( ) find that physical attractiveness has a significant (p < . ) positive effect on income. in a separate analysis, however, the significant effect only holds for men, not for women. using three separate representative samples from the united states and canada, hamermesh and biddle ( ) find that physical attractiveness has a strong effect on hourly earnings, and the effect is much stronger for men (p < . ) than for women (p < . ). the significant effect of physical attractiveness on income has been documented in longitudinal studies of two professions. in their study of mba graduates, frieze, olson, and russell ( ) show that more attractive men have a significantly (p < . ) higher starting salaries and their advantage increases over time. for women, attractiveness has no effect on starting salaries, but more beautiful women earn significantly (p < . ) more later in their careers. in their sample, men earn us$ more on average for each unit of attractiveness (on a five-point scale), and women earn us$ more. in their longitudinal study of lawyers, biddle and hamermesh ( ) show that better-looking attorneys earn more than others years after graduation from law school, and their advantage increases over time. once again, the effect of physical attractiveness on income is stronger for men than for women; the regression coefficient for the effect of standardized beauty on log(earnings) is . (p < . ) for men and . (ns) for women. biddle and hamermesh specifically rule out employer discrimination as the cause of the beauty premium among lawyers because those in the private sector (who are self-employed) benefit from their physical attractiveness as much as (if not more than) those in the public sector. biddle and hamermesh cannot rule out the effect of client discrimination, however. . discussion table summarizes all the empirical studies in support of the assumptions and the theorem. there appears to be some evidence for each of the four assumptions (assumptions – ). given the available empirical evidence, we feel confident to conclude that people have the perception that beautiful people are more intelligent because they indeed are more intelligent. there is also evidence to support this conclusion (theorem ). we thank douglas t. kenrick for making this point. table evidence for the assumptions and the theorem a . more intelligent men are more likely to attain higher status than less intelligent men (austin & hanisch, ; ball, ; fryer, ; ghiselli, ; harrell & harrell, ; hunter, ; hunter & hunter, ; jencks, ; jensen, ; mascie-taylor & gibson, ; reynolds et al., ; terman & oden, ; thorndike & hagen, ; u.s. department of labor, ; waller, ) a . higher-status men are more likely to mate with more beautiful women than lower-status men (davis, ; elder, ; hamermesh & biddle, ; taylor & glen, ; udry, ; udry & eckland, ) a . competence is heritable bouchard & mcgue, (review); bouchard et al. (review); pedersen et al., (review); plomin & defries, (review); wang & oakland, a . beauty is heritable livshits & kobyliansky, ; mcgovern, neale, and kendler, ; møller & thornhill, (meta-analysis); rowe, clapp, & wallis, t . more beautiful people are more intelligent than less beautiful people biddle & hamermesh, ; elder, ; frieze et al., ; furlow et al., ; hamermesh & biddle, ; jackson et al., (meta-analysis); langlois et al., (meta-analysis); roszell et al., ; zebrowitz et al., s. kanazawa, j.l. kovar / intelligence ( ) – it goes without saying that our contention that beautiful people are more intelligent is purely scientific (logical and empirical); it is not a prescription for how to treat or judge others. to derive a behavioral prescription (what one ought to do) from a scientific conclusion (what is) would be an example of what hume ( / ) calls the ‘‘naturalistic fallacy.’’ at the same time, our theory is probabilistic, not deterministic, and the available evidence suggests that the empirical correlation between physical attractiveness and intelligence, far from being . , is modest at best. thus, any attempt to infer people’s intelligence and competence from their physical appearance, in lieu of a standardized iq test, would be highly inefficient. our theory identifies but one mechanism which produces the extrinsic correlation between beauty and intelligence. it is important to emphasize that we do not claim that the mechanism we identify is the only possible one. in fact, our theory is compatible with other potential mechanisms that create the correlation (extrinsic or intrinsic) between beauty and intelligence, such as self-fulfilling prophecy (snyder et al., ) and the ecological theory of social perception (zebrowitz et al., ). for instance, the weak empirical correlation between beauty and intelligence produced by assortative mating can be strength- ened further by self-fulfilling prophecy. that is why we have made no effort to rule out alternative explanations; the truth of our theory does not depend on their falseness. however, our theory, and the evidence we present in its support, does mean that the empirical correlation between beauty and intelligence can occur through assortative mating alone, even in the absence of all other mechanisms. we can also derive other novel hypotheses from our theory. to the best of our knowledge, there currently exist no empirical data available to test these hypotheses. first, the perception that beautiful people are more intelligent should be culturally universal. we contend that this perception is part of a species-typical evolved psychological mechanism. thus, our evolutionary psychological theory leads us to conclude that the perception that beautiful people are more intelligent, far from a mere ‘‘bias’’ in the contemporary western societies, should exist in every human society. s. kanazawa, j.l. kovar / intelligence ( ) – second, the empirical correlation between beauty and intelligence should be culturally universal. to the extent that men’s preference for beautiful women, and women’s preference for high-status men are culturally universal (buss, ), then the assortative mating of beautiful women and intelligent, high- status men, the mechanism we posit behind the extrinsic correlation, should also be culturally universal. the actual extent of empirical correlation may vary from society to society, however. third, the actual extent of empirical correlation between beauty and intelligence should be stronger in polygynous societies than in monogamous societies. monogamy, by limiting even the highest-status man to one legal wife at a time, weakens the extent to which assumption holds. in polygynous societies, the most intelligent men of highest status can mate and reproduce with several of the most beautiful women (betzig, ), thereby increasing the correlation between beauty and intelligence among their offspring. in monogamous societies, all but one of the most beautiful women would have to mate with less intelligent men, and the correlation between beauty and intelligence among their offspring will therefore weaken. we suspect that this might be why jackson et al.’s ( ) and langlois et al.’s ( ) meta-analyses find a weak effect size for the correlation between physical attractiveness and intelligence among adults. all of the studies were conducted in monogamous societies, most of them in the united states. we expect the effect size to be larger if the meta-analysis includes (hitherto nonexistent) studies conducted in polygynous societies (or at least less monogamous societies or societies with shorter histories of monogamy). finally, while we have concentrated on the relationship between beauty and intelligence in this paper, our evolutionary psychological theory can explain people’s perception, and the extrinsic correlation, between beauty and any other heritable trait that helps men attain higher status. take aggression, for instance. to the extent that aggression helps men attain higher status (or it did so in the ancestral environment), and to the extent that aggression is genetically heritable, we expect a positive correlation between beauty and aggression. to explain such a correlation, all we have to do is substitute intelligence with aggression in assumptions and . assumption . more aggressive men are more likely to occupy higher status than less aggressive men. assumption . higher-status men are more likely to mate with more beautiful women than lower-status men. assumption . aggression is heritable, such that sons and daughters of more aggressive men are more aggressive than sons and daughters of less aggressive men. one logical requirement for our theory is that traits that help men attain higher status (such as intelligence or aggressiveness) not diminish beauty when they occur among women. to the extent that they do, the correlation between such traits and beauty among daughters will be diminished. higher levels of testosterone might be an example of such a trait, which simultaneously increases men’s status and decreases women’s beauty. we thank jeremy freese for making this point. in this context, however, it is important to distinguish between a woman’s beauty and her desirability as a mate. the two are very closely related, but not the same. height is a case in point. as we note above, men’s height is positively correlated with their status. to the extent that height is heritable, then the daughters of high-status men (with their beautiful wives) will be tall as well as beautiful. however, there is some evidence that height might decrease women’s desirability as mates. in one study, the husband is taller than the wife in . % of all married couples (n = ) (gillis & avis, ); thus, taller women generally have a smaller pool of potential mates than shorter women. this is probably why half the women surveyed in another study want to be shorter than they are, while virtually all men want to be taller than they are (calden, lundy, & schlafer, ). however, there is no reason to believe that height diminishes women’s beauty, measured by the symmetry and averageness of their facial and bodily features. s. kanazawa, j.l. kovar / intelligence ( ) – assumption . beauty is heritable, such that sons and daughters of more beautiful women are more beautiful than sons and daughters of less beautiful women. theorem . more beautiful people are more aggressive. if both assumptions and (in addition to assumptions and ) are empirically true, as we suspect they might be, then the conclusion that beautiful people are more aggressive is logically true. the same logic can explain the observed correlations between beauty and social skills, or beauty and dominance (feingold ), among others. we suggest that good-looking people might be exactly what we think. acknowledgements we thank mary c. still for the original inspiration, nancy l. segal and randy thornhill for providing us with key references, and jeremy freese, christine horne, john orbell, craig t. palmer, and paul j. quirk for their comments on earlier drafts. references austin, j. t., & hanisch, k. a. 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( ). looking smart and looking good: facial cues to intelligence and their origins. personality and social psychology bulletin, , – . http://eab.sagepub.com environment and behavior doi: . / ; ; environment and behavior robert g. ribe landscape perceptions is scenic beauty a proxy for acceptable management?: the influence of environmental attitudes on http://eab.sagepub.com/cgi/content/abstract/ / / the online version of this article can be found at: published by: http://www.sagepublications.com on behalf of: environmental design research association can be found at:environment and behavior additional services and information for http://eab.sagepub.com/cgi/alerts email alerts: http://eab.sagepub.com/subscriptions subscriptions: http://www.sagepub.com/journalsreprints.navreprints: http://www.sagepub.com/journalspermissions.navpermissions: http://eab.sagepub.com/cgi/content/abstract/ / / #bibl sage journals online and highwire press platforms): (this article cites articles hosted on the citations © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://www.edra.org/ http://eab.sagepub.com/cgi/alerts http://eab.sagepub.com/subscriptions http://www.sagepub.com/journalsreprints.nav http://www.sagepub.com/journalspermissions.nav http://eab.sagepub.com/cgi/content/abstract/ / / #bibl http://eab.sagepub.com . / environment and behavior / november ribe / beauty versus acceptability is scenic beauty a proxy for acceptable management? the influence of environmental attitudes on landscape perceptions robert g. ribe teaches landscape architecture, community and regional plan- ning, and environmental studies. he has consulted and worked for public agencies and private firms in land planning and holds ph.d., m.a., and m.s. degrees from the university of wisconsin. abstract: pacific northwest mountain scenes tested whether perceptions of sce- nic beauty correspond to those of management acceptability, and for whom. a strati- fied sample of participants included those favoring resource protection, production, or neither. scenes were rated for either scenic beauty or acceptability. all participants saw very beautiful scenes as acceptable, and the two rating types were correlated but diverged in ways corresponding to environmental attitudes. participants with oppo- site attitudes rendered the two ratings in reversed ways: those favoring resource pro- duction had lower standards for both qualities, rated acceptability higher than beauty, and saw ugly scenes as acceptable. those favoring resource protection had higher standards for both qualities, rated acceptability lower than beauty, and needed beauty to see acceptable management. the nonaligned respondents were in between, judging the two qualities very similarly. beauty can be a proxy for acceptability within homo- geneous or general constituencies but only with careful interpretation across conflict- ing value orientations. public land management has always been contentious. scenery is one of the most ubiquitous ways by which the health of public landscapes is judged by the public. managers have therefore been justifiably sensitive about scenic author’s note: this study is a product of the demonstration of ecosystem man- agement options project, a joint effort of the united states department of agriculture forest service region and pacific northwest research station. research partners environment and behavior, vol. no. , november - doi: . / © sage publications © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com quality, as was congress when it included provisions for scenic beauty in the national environmental policy act (nepa) of and the national forest management act of . still, the relationship between public judgments of scenic quality versus the acceptability of public land conditions remains unclear. one common example of the confusion of perceived acceptability versus scenic beauty arises in land planning executed under the procedural require- ments of nepa. these procedures follow a rational planning process (meyerson & banfield, ) whereby objective assessments of the environ- mental impacts of alternative plans precede an overall evaluation of options and choice of action. planners must make objective assessments of social impacts and aesthetic or visual impacts, among many others, but no assess- ment of the perceived social acceptability of alternatives is required. instead, final authorities who select plans for implementation must make judgments about the perceived social acceptability of alternatives using informed, administrative discretion, often based on ad hoc understandings or guesses about social acceptability, just as in decisions made by elected officials. these decisions are made from the totality of many different topical impact assessments, public comments, and, inevitably, politics. this process is intended to allow only more objective assessments to affect choices, to pre- vent any formal assessment of social acceptability that might trump all other assessments, and to rest final decision assessments not with specialists but with decision makers who are vested with such powers (buck, ). for all its virtues, this inattention to carefully understanding the perceived social acceptability of planning decisions can be perilous. an overattention to strict nepa process and to an overly technical decision analysis motivated by agency interests can lead to serious planning failures when final decisions prove socially unacceptable (wondolleck, ). one way to avoid such fail- ures is to better understand the political or social acceptability of alternatives (gericke & sullivan, ). studies to foster such understandings have begun (brunson, ; brunson, kruger, tyler, & schroeder, ), and methods for assessing social acceptability are being explored (zinn, manfredo, vaske, & wittmann, ). there is a frequently used, weak default for incorporating quasi- assessments of social acceptability into planners’ fact finding. this has been to use required assessments of visual-aesthetic impact as a proxy for per- ceived social acceptability (smardon, ). the default assumption has environment and behavior / november include the university of washington, oregon state university, university of oregon, gifford pinchot and umpqua national forests, and the washington state department of natural resources. thanks also to molly matteson, who assisted in the survey. © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com been that if a landscape is seen as acceptably attractive, then the public may find the plan, and environmental impacts that produced that landscape, acceptable (greider & garkovich, ; magill, ; mcguire, ). this assumption is problematic because scenic beauty assessments or per- ceptions may be hard to justify as a measure of the acceptability of land- scapes. they may oversimplify the many, complex, and controversial issues that make up acceptability and mask important differences of opinion behind shared aesthetic perceptions of a lowest common denominator kind (carlson, ). researchers have also made the same assumption about the identity of aesthetic versus acceptability perceptions (paquet & belanger, ) or have forced an identity by having respondents rate “scenic acceptability” (brunson & reiter, ). even if this leap of logic has not been clearly validated, nepa provides lit- tle other objective recourse. decision makers likely recognize that scenic beauty and acceptability are not identical. to the extent they are supposed to, or conscientiously do, rely only on the assessments in hand, they often must decide, or at least explain decisions, as if scenic beauty is a proxy for per- ceived acceptability. the weight of public comments may bolster their intu- itive sense of nonaesthetic acceptability perceptions as they do so. an alternative source of findings about decisions’ acceptability could come from more robust public participation than the law requires (blahna & yonts- shepard, ), or that planners are usually enabled to do (creighton, chalmers, & branch, ) or that they are willing to do (shindler, steel, & list, ). meanwhile, assumptions about the relationship between percep- tions of scenic quality versus the acceptability of landscapes have long been known to be problematic (dearden, ; zube, ) and are overdue for targeted investigation. beauty, acceptability, and attitudes the full nature of aesthetic, affective perceptions of outdoor environments versus cognitive perceptions of approval is complex and unknown. in the absence of conditioning information or knowledge, affective visual percep- tions, such as scenic beauty, may not necessarily be substantially different than more cognitive perceptions, such as those of the acceptability of land- scapes’ management (zajonc, ). if cognitive perceptions are normative, like judgments of acceptability, affective visual perceptions may dominate their formation (ulrich, ; zajonc, ). to the extent that perceptions of acceptability are only partly affective perceptions, the two types may be ribe / beauty versus acceptability © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com significantly different, inasmuch as they may arise from different expectation schema (purcell, ). to the extent that acceptability perceptions are mainly cognitive, in deriving an intentional approval behavior, they may also be significantly different from affective beauty perceptions (russell, ward, & pratt, ). whether these two types of perception differ may also be dependent on the kind of person responding to a landscape. subjective atti- tudes almost always affect cognitive perceptions, and different kinds of peo- ple have been found to render different aesthetic perceptions of landscapes (kaplan & talbot, ; lyons, ; noe, ; ribe, ). there is extensive published research about affective landscape percep- tions and studies comparing how types of people render such perceptions. there is also literature about perceptions of the content of environmental management—as opposed to its appearance—and how these vary among people with different environmental attitudes. little published research has explicitly explored how perceptions of management acceptability relate to those of scenic quality, although it is well established that normative expecta- tions of or associations with land use types and designations affect aesthetic perceptions in understandable ways (anderson, ; hodgson & thayer, ; wohlwill & harris, ). a few studies have investigated the relationship between aesthetic and acceptability perceptions. more ecologically sensitive respondents were more sensitive to the acceptability of visual impacts, when the latter were described in words rather than seen in landscapes (floyd, jang, & noe, ) or when they were mapped from memory (harvey, ). brotherton and devall ( ) found that scenic beauty and acceptability perceptions were most correlated when they both derived from afforestation projects that were seen as more natural appearing. brunson and shelby ( ) explored the relationship between perceived scenic beauty and recreational-setting acceptability and found them strongly but imperfectly correlated. ribe ( ) compared average scenic beauty and management acceptability rat- ings for six scenes and found the order of these two perception types to be largely the same but with significant differences in their interval differences across scenes. affective responses to landscapes may be changed by cognitive process- ing arising from information provided to the observer. studies have found that cognitive perceptions, such as acceptability judgments, are affected by information. just a few studies have explored the influence of information on aesthetic perceptions of outdoor environments. ribe ( ) found that infor- mation influenced perceptions of acceptability more than those of beauty. information that explicitly refers to strongly affective attributes of scenery, such as dead and burned trees, does moderate negative scenic beauty environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com perceptions (buhyoff, wellman, & daniel, ; taylor & daniel, ). information about land management not explicitly related to affective attrib- utes of scenery has no such clear effects (brunson & reiter, ). much needs to be learned about these relationships, but this issue was not explored in the study reported here. none of these studies has explored the correlation of simple perceptions of scenic quality versus management acceptability for different types of people and for a large sample of scenes. none has clearly and specifically tested the assumption that scenically beautiful landscapes are acceptable landscapes, and for whom. the best guidance now available is theoretical ideas about this relationship (gobster, ; nassauer, ; thayer, ). the relation between simple, uninformed perceptions of scenic beauty and acceptability is important, if only because these judgments on simply seeing landscapes are commonplace and can have potentially powerful emotional impacts that can affect lasting public opinions and activism regarding land management (palmer, ; tarrant & green, ). study outline this study investigated the relationship between beauty and acceptability perceptions using methods detailed in the next section. it employed the north- ern spotted owl controversy (yaffee, ) as a context for a survey. respon- dents were drawn from the region directly affected by the controversy, where the issues were widely understood in relation to forest and landscape condi- tions (dietrich, ). this provided a strong context for scenic acceptability judgments that could readily be different from scenic beauty judgments. the forested mountain landscape of the spotted owl provided a diverse range of scenes for judging. issues from the controversy were used to measure respon- dents’ attitudes (walker & daniels, ). a large, diverse sample of respondents was surveyed. they were sorted along a spectrum of favorability toward habitat protection for the spotted owl. this sorting classified respondents with different attitudes toward environ- mental protection, which can affect scenic perceptions (mccool, benson, & ashor, ; tips & savasdidara, ). the perceptions of members of these attitude classes were then compared to test (a) whether some classes saw differences in beauty versus acceptability differently than others, (b) whether respondent classes differed in their relative standards of judgment for these two qualities, (c) whether these attitude classes’ standards differed in judging either one of the qualities alone, and (d) whether any of the above three comparisons produced differences throughout the full range of beauty found in the scene sample. ribe / beauty versus acceptability © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com method scene sample there were photographic slides taken of vista views in the cascade and olympic mountains of oregon and washington. these sampled a wide range of scenic beauty and a wide range of evidence of human activity, from scenes of wilderness to scenes dominated by fresh clear-cuts and roads (carls, ). (this large number of scenes served to include all the condi- tions required for another study of scene content using the same ratings.) fifty-five of these were placed at random in one slide set, and the other were placed randomly in another slide set. another separate set of slides with the same range of scenery was placed at the start of both slide sets to pro- vide respondents with warm-up practice ratings. these were not otherwise included in the study. this procedure produced two similar sets of slides for rating by different respondents. this split into two sets was done to keep the time required for rating within acceptable limits for the groups that volun- teered to rate them. respondent sample a total of , respondents was surveyed. these were members of a vari- ety of organizations in western washington and oregon who rated the slides as an activity during meetings. groups were recruited to capture a diversity of people with active interests in preservation versus commodity production on public lands. a few people attending the meetings opted not to participate and were not counted, so a response rate cannot be reported. eighty-five respondents rated the slides but opted not to answer the questions needed to classify their attitudes regarding public lands management, so they were excluded from the study. this yielded a final sample of , respondents. the respondents were not classified or analyzed according to their mem- bership in the groups whose meetings provided the respondents. instead, each individual respondent was classified later on independently of his or her surveyed group membership. this was done according to his or her own responses to questionnaire items regarding national forest issues. this classi- fication method is described in the next section. this was not a poll sample. instead, respondent groups were recruited to capture a stratified sample of roughly equal numbers of people in three sets: (a) those with active interests in commodity production on public lands, or resource-productionist attitudes; (b) those with ecological preservation or environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com resource-protectionist attitudes; and (c) other nonaligned people tending toward what might be considered more moderate views about environmental issues. these three types were identified by vining ( ) as tending to react to forest issues with different attitudes and emotions, consistent with walker and daniels’s ( ) findings. the groups sampled were recruited to capture a variety of rural, suburban, and urban respondents and the potential range of attitudes toward land man- agement found across such places (brunson, shindler, & steel, ; tremblay & dunlap, ). diversity was also sought in people’s relation- ships to the forest products industry and in their recreational preferences. the groups included organizations such as logging and property rights advocates, environmental groups of various kinds, and other groups including civic clubs, professional organizations, higher education classes, business clubs, corporate offices, granges, recreation interest clubs, and neighborhood associations. each respondent group rated just one of the two slide sets for either acceptability or scenic beauty, entailing four different respondent subsamples: (a) slide set rating acceptability, (b) slide set rating accept- ability, (c) slide set rating scenic beauty, and (d) slide set rating scenic beauty. respondent groups were initially allocated to these subsamples at random. then, decisions were made about which scene set and quality the last groups would rate to ensure that each of the four subsamples would cap- ture at least of the three respondent attitude classes (productionist, protec- tionist, and nonaligned). to pursue this desired balance within the slide set–rated and quality-rated subsamples across the three respondent categories, a running tally of responses to the propositions in table was kept as sampling progressed. final groups were then recruited that were expected to balance each subsample until the balance was achieved with at least respondents in each of the four subsamples (slide set–rated and quality-rated combinations). this running count of respondent types was temporary for sampling purposes only. another better and final classification of all respondents is described in the next section, and the corresponding final number of respondents in each category is shown in table . respondent classification the completed sample was sorted by respondents’ individual attitudes toward resource production from national forests to yield the classification used for further analysis. the stepwise, k-means, cluster analysis method of nonhierarchical estimate minimization using standardized data was used ribe / beauty versus acceptability © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com table response distributions among final respondent subsamples to propositions regarding the spotted owl all respondents productionists protectionists nonaligned proposition (n = , ) (n = ) (n = ) (n = ) i believe the northern spotted owl is not really threatened with extinction. strongly disagree disagree neutral or not sure agree strongly agree i believe there is no real conflict between saving the northern spotted owl and continuing levels of federal forest harvests like those of the s and s. strongly disagree disagree neutral or not sure agree strongly agree i believe the northern spotted owl should be saved only if it can be done without eliminating jobs and significantly hurting the economies of communities.a strongly disagree disagree neutral or not sure agree strongly agree © s a g e p u b lic a tio n s . a ll rig h ts re s e rv e d . n o t fo r c o m m e rc ia l u s e o r u n a u th o rize d d is trib u tio n . a t u n iv o f o r e g o n o n a p ril , h ttp ://e a b .sa g e p u b .co m d o w n lo a d e d fro m http://eab.sagepub.com i believe the northern spotted owl should be saved even at a high eco- nomic cost.b strongly disagree disagree neutral or not sure agree strongly agree i believe the northern spotted owl should be saved only if it can be done without significantly hurting private property owners’ rights and freedom of land use.c strongly disagree disagree neutral or not sure agree strongly agree note: for clustering purposes, response options were integer coded from (strongly disagree) to (strongly agree). a. efficient final clustering item, with average cluster values: productionists = . , protectionists = . , and nonaligned = . . b. efficient final clustering item, with average cluster values: productionists = . , protectionists = . , and nonaligned = . . c. efficient final clustering item, with average cluster values: productionists = . , protectionists = . , and nonaligned = . . © s a g e p u b lic a tio n s . a ll rig h ts re s e rv e d . n o t fo r c o m m e rc ia l u s e o r u n a u th o rize d d is trib u tio n . a t u n iv o f o r e g o n o n a p ril , h ttp ://e a b .sa g e p u b .co m d o w n lo a d e d fro m http://eab.sagepub.com (forgy, ; sas institute, ). this method clustered the respondents into those closest to each other in euclidean space as defined by their answers to the spotted owl propositions in table . k-means was the best method for this classification to an a priori, set number of classes with the data type and structure in this study (milligan, ) and succeeded in sorting to the expected three respondent types right away, using all combinations of the spotted owl propositions. the most efficient and final clustering used the responses to the three propositions (see table ) regarding jobs and communities, the cost of saving the owl, and property rights. that is, the clusters of respondents resulting from those three items together had mean response values the furthest apart and the smallest mean distance inside the clusters (gengerelli, ). an inspection of the data sorted by final clusters in table , and the mean responses noted in that table, provides a sense of the character and strong expected differences between the respondent classifications. scene rating sessions a slide set was projected in random order for each respondent group after they were read instructions. the respondents rated the slides privately, anon- ymously, and independently on individual rating forms and then filled in a questionnaire. the respondent groups that rated the slides for scenic beauty did so on a numeric scale from – to + . they were instructed that the scale ranged from very ugly (– ) to very beautiful (+ ), with assigned to slides they found nei- ther beautiful nor ugly or were undecided about. the respondent groups that rated the slides for acceptability were asked to rate each slide for “its acceptability as a national forest condition,” reflecting “how much the landscape shown is in a condition that is acceptable for a pub- licly owned and managed national forest.” they were instructed to apply whatever knowledge and sensibilities regarding national forest management they wished to these judgments. these acceptability ratings were also made on a numeric scale from – to + . they were instructed that the scale ranged from very unacceptable (– ) to very acceptable (+ ), with assigned to slides they found to be neither acceptable nor unacceptable or were unde- cided about. respondents were asked to try to use the whole scale in rating slides. the only information provided was that the scenes were from various national forest lands and collectively portrayed multiple uses and not just recreation areas. respondents were told to view the slides as scenes they might encounter traveling “distant from home” through the cascade mountains environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com and “distant from their favorite place to visit” (lyons, ). they were asked to rate the scenes without reference to their frames, the appearance of the sky, or the quality of the photographic exposure. analysis of rating types within respondent classifications all the scenic beauty ratings rendered for each slide by all respondents were averaged, and the same was done for the acceptability ratings (schroeder, ). they were then averaged again but within each of the three respondent attitude classifications. the average ratings for acceptability versus scenic beauty within each of the respondent classifications, as well as among all the respondents, were compared across all scenes. for each such comparison, these two rating types were plotted against each other in order of the mean of the scene’s two (scenic beauty and acceptability) ratings (see figure ). in each such compar- ison, a two-way anova was used to test whether the two different but related types of ratings exhibited significantly different mean values. this was a pairwise analysis by scene, not by respondent. in each case, different ribe / beauty versus acceptability figure : comparing acceptability versus scenic beauty ratings within respondent classifications © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com respondent sets but in the same attitude classification produced the two dif- ferent ratings. it was possible that a classification of respondents would not have signifi- cantly different mean acceptability versus scenic beauty ratings, but they might have exhibited significantly different ratings only within a limited range of the rating values rendered, such as only among ugly and/or beautiful scenes. this was an important potential difference that could be tested by comparing the slopes between the two rating types with changes in the under- lying scenic beauty that affected both types of ratings. within each respondent classification, these differences in the slope of the scenic beauty versus acceptability plots were tested in a manner suggested by schroeder ( ). this was done by a post hoc t test. (this test was found to be more conservative than an analysis of covariance with average scenic beauty ratings across all respondents.) a simple regression model was esti- mated between each of the two rating types and their combined mean rating values by scene. the resulting estimated slope coefficients for the two rated qualities were then compared for a significant difference using a t test employing standard errors derived from the regression estimations. analysis across respondent types within rating types in a different analysis, just the average acceptability ratings across the three attitude classes of respondents were compared across all scenes. this was done by plotting them against each other by scene in the order of the mean of these three acceptability ratings (see figure , top). these three plots were tested for significant differences in their pairwise mean values by anovas. each pairwise difference was also subjected to a post hoc scheffe ( ) test derived from a three-way anova involving all three attitude classes. this additional test was used because it is conservative in identifying significant differences and is robust against imperfectly met anova assumptions. these were repeated measures anova by scene, not by respondent. different respondents of different classifications were making the same acceptability ratings. the same post hoc t tests described above were used (for the same reasons) to do pairwise comparisons of plot slopes across the respondent classifications. the average scenic beauty ratings by attitude class were also plotted together (figure , bottom). identical analysis procedures as above were applied to these average scenic beauty ratings across the three respondent attitude classes. environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com results comparing rating types within respondent types the graphs comparing average scenic beauty to acceptability ratings across all the scenes are in figure . the two types of ratings there were always correlated. inspection of all four plots suggests the ratings converged ribe / beauty versus acceptability figure : comparing the same rating types across respondent classifications © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com at the right-hand end at high values for both qualities, indicating that scenes rated with high scenic beauty strongly tend to also garner similarly high acceptability ratings. where clear differences between average acceptability and scenic beauty ratings did occur, only for the productionists and protec- tionists, they appeared more evident for scenes of medium and low scenic beauty. still, for all respondent classes, only a relatively small number of scenes garnered a positive average rating for one quality and a negative aver- age rating for the other quality. the plot in figure for respondents classified as productionists showed a statistically significant difference between their acceptability versus scenic beauty ratings, including a significant difference between the two qualities’ best-fit linear slopes (see table ). these productionist respondents exhibited lower average standards for rating scenes’ acceptability than scenic beauty and consequently tended to rate acceptability higher than scenic beauty. the plot in figure for protectionists exhibited the opposite pattern, indi- cating that this class of respondents rendered higher scenic beauty ratings (lower standards) than acceptability ratings (higher standards). the protec- tionists produced a statistically significant difference between their accept- ability and scenic beauty ratings (see table ). this difference, however, was clearly only between the average level of those ratings. it was not between the two qualities’ slopes across the graph, which were not significantly different (see table ). the plot in figure for the respondents classified as nonaligned did not exhibit a statistically different pattern (level and slope) of average acceptabil- ity versus scenic beauty ratings across the scenes. the last plot in figure of ratings averaged across all the respondents showed a very similar pattern to environment and behavior / november table anovas for ratings of scenes’acceptability versus scenic beauty within respondent types error error sum of mean mean f compare source of variance squares square square ratio slopes t a acceptability and scenic beauty productionist . . . . * . * protectionist , . . . . * . nonaligned . . . . . all respondents . . . . . note: this table presents separate, two-category, related measures one-way anova models. a. degrees of freedom are / . *p < . . © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com the nonaligned subsample, also without any statistically significant differ- ence between the two qualities rated. comparing respondent types within qualities rated the graphs comparing the scenes’ average ratings for one type of quality at a time between respondent classifications are in figure . here, too, the average ratings of the different respondent classifications were correlated and converged among scenes rated with high scenic beauty and high accept- ability, indicating strong agreement there among respondents of different classifications. when differences between respondent classifications’ aver- age acceptability or scenic beauty ratings did occur in figure , they were more noticeable for scenes that had medium and low scenic beauty. among these medium- to low-level ratings, there were no two classifications of respondents that obviously agreed about either quality rated. in comparing these same-quality perceptions across different classes of respondents (see figure ), quite a few scenes garnered positive average ratings from one or two attitude classes but negative average ratings from the other class(es). the plot comparing average acceptability ratings at the top of figure exhibited statistically significant differences in the overall level of accept- ability ratings between all pairs of attitude classes (see table ). all compari- sons of acceptability ratings’ plot slopes between any two attitude classes were also significantly different. this indicates that the most significant dif- ference between the three classes of respondents occurred among less accept- able scenes, where the plots in figure diverged. the productionist respondents had the lowest acceptability standards and the highest ratings, the protectionists showed the opposite pattern, whereas the nonaligned respondents were in between. the plot comparing average scenic beauty ratings at the bottom of figure exhibited the same pattern of all statistically significant differences (see table ) as that above it did for acceptability ratings. this scenic beauty plot had smaller differences between the respondent classifications in both levels and slopes and correspondingly smaller anova error terms (see table ). discussion the systematic and often significant differences observed between acceptability and scenic beauty ratings indicate that a distinction should be made between these constructs in survey research and land management. ribe / beauty versus acceptability © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com table anovas for ratings of scenes’acceptability or scenic beauty among respondent types error error sum of mean mean mean compare source of variance squares square square f ratioa difference slopes ta acceptability models productionists and nonaligneda . . . . * . ** . * protectionists and nonaligneda . . . . * . ** . * productionists and protectionistsa . . . . * . ** . * productionists, protectionist, and nonalignedb . . . . * .na .na scenic beauty models productionists and nonaligneda . . . . * . ** . * protectionists and nonaligneda . . . . * . ** . * productionists and protectionistsa . . . . * . ** . * productionist, protectionists, and nonalignedb . . . . * .na .na note: na = not applicable. this table presents eight separate, repeated measures by scene anova models. a. degrees of freedom are / . b. degrees of freedom are / . *p < . . **p < . , for scheffe’s post hoc test using the last three-way model listed for each quality. © s a g e p u b lic a tio n s . a ll rig h ts re s e rv e d . n o t fo r c o m m e rc ia l u s e o r u n a u th o rize d d is trib u tio n . a t u n iv o f o r e g o n o n a p ril , h ttp ://e a b .sa g e p u b .co m d o w n lo a d e d fro m http://eab.sagepub.com they are strongly correlated but should not be conflated or assumed to be identical. people with different types of environmental attitudes agree that the most beautiful landscapes are also the most acceptable, consistent with tips and savasdidara’s ( ) findings. all these acceptability perceptions of beauti- ful landscapes may be saturated by strong positive affects overriding cogni- tive considerations. this shared perception of ideal environments, perhaps best reflected in the national parks movement, seems to found the identifica- tion of beauty with healthy landscapes (cox, ). when considering land- scapes of less than high or ideal beauty, perceived beauty and acceptability remain correlated in trend and polarity but diverge between people with dif- ferent environmental attitudes as scenic beauty declines. as figure shows, people with attitudes emphasizing the active manage- ment of public lands for resource exploitation (productionists) tend to judge scenic beauty differently than acceptability. they tend to see landscapes with evidence of management as more acceptable than beautiful. they tend never to see any landscape as unacceptable, even if they find it ugly. these productionists tend to see clear-cuts or other evidence of management as ugly, consistent with general aesthetic norms (ribe, ), but are more for- giving of that evidence in judging such scenes with higher, positive accept- ability. they also judge such ugly scenes with a bit more beauty than do people with other kinds of public land management attitudes (see figure ). these productionists tend to judge scenes with evident management as hav- ing substantially more acceptability than do people with other attitudes, and more so as scenes get uglier (see figure ). this seems consistent with their more industrial or “pre-materialist” perspective toward land management (steger, pierce, steel, & lovrich, ). people with more “postmaterialist” or postindustrial attitudes favoring management of public lands to support natural processes (protectionists) also tend to judge landscape scenes’ beauty differently than acceptability. but they judge the difference in the opposite way than the productionists dis- cussed above, instead viewing landscapes with evidence of management as less acceptable than beautiful (see figure ). they tend to see all ugly land- scapes as unacceptable (see figure ) and clear-cuts or other evidence of management as ugly, consistent with general aesthetic norms, but are more unforgiving of that evidence in judging such scenes with even lower accept- ability than beauty. they judge such ugly scenes with a bit less beauty than do people with other public land management attitudes (see figure ). these protectionists judge scenes with evident management as having substantially less acceptability than do people with other attitudes, and more so as scenes get uglier (see figure ). ribe / beauty versus acceptability © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com people with more nonaligned attitudes, favoring both resource exploita- tion and nature protection on public lands, or neither strongly, evidently see little difference in judging the acceptability versus scenic beauty of land- scapes (see figure ). if nonaligned people constitute a majority, as they might (lovrich & pierce, ), an emphasis on scenic beauty in managing for acceptable landscapes seems warranted in serving the general public. the same conclusion is supported by the identity of scenic beauty and acceptabil- ity perceptions among all the respondents’ averaged ratings, provided that the numbers of productionists and protectionists were balanced so as to cancel each other to produce very similar perceptions as nonaligned people (see fig- ure ). similarly, nonaligned people’s perceptions of either acceptability or scenic beauty tend to be distinctly midway between those of people with the other two types of attitudes (see figure ), again acting as surrogates for a bal- anced average of the other two attitude classes. interpretations people usually arrive at a landscape or land use controversy with predis- posed attitudes and preferences derived from experience. these normative predispositions typically have some basis in affective emotions that strongly influence people’s values (zajonc, ), such as favoring resource protec- tion. these values may then be reconfirmed by new affective perceptions on encountering a new landscape or controversy. more cognitive ideas or analy- sis may then be overlaid on affective perceptions in arriving at perceptions of landscape acceptability, perhaps through an interest or involvement in the decision-making process. affectively derived perspectives may remain a powerful foundation for these more cognitive perceptions. this study did not investigate the influence of information or participation in planning on perceptions of landscape acceptability. it focused on initial or primary judgments of scenes made without information about landscapes other than that visually evident. it compared how people with very different values added cognitive preferences to their affective reactions to landscape scenes in forming perceptions of acceptability. perceptions among people sharing similar values average scenic beauty ratings within any one attitude class were corre- lated with acceptability ratings, and beautiful scenes tended very often to be acceptable and vice versa (see figure ). among simple landscape environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com perceptions of people with similar values, scenic beauty is therefore a pretty good proxy for acceptability. in such cases, aesthetic perceptions unaffected by information seem to strongly determine perceptions of acceptability. among constituencies that do not have strong attitudes either for resource production or protection, average perceptions of scenic beauty versus accept- ability are not only correlated but tend to match each other in magnitude. these people are either less able to distinguish the difference between these perception types or are so able but tend to see scenic beauty as a primary indi- cator of acceptability and, hence, see no significant difference between the two qualities. for these nonaligned people, scenic beauty is a strong proxy for acceptability. the same holds for the larger public, if the number of people favoring resource protection versus production is similar enough to offset each other in “voting” or valuing their perceptions. scenic beauty assessments are, however, not perfect proxies for percep- tions of acceptability within sets of people with similar and strong environ- mental attitudes. the same measurement protocol applied to similar participants, with only a change in instructions about the quality to rate, can produce significantly but not radically different average ratings. environ- mentalists see significantly less acceptability than scenic beauty, whereas people favoring resource extraction see more acceptability than scenic beauty. these opposite ways of modulating aesthetic perceptions into more cognitive ones disappear only among the most beautiful scenes where all per- ceptions converge, as they do for everyone. perceptions across people with different values the subtle differences between perception types within attitude classes described above are compounded when perceptions are compared across constituencies with different attitudes. in the latter case, scenic beauty is only a proxy for acceptability to the extent that increases in average perceived lev- els of one quality do correlate to increases in the other. the level and/or rate at which these correlations occur vary significantly among land management constituencies, revealing important differences in their perceptions. these differences across people with different values occur in comparing either their scenic beauty or acceptability perceptions. differences might only have been expected among the latter cognitive perceptions, with strong agreement about scenic beauty. instead, attributes of the scenes related to people’s par- ticular values did affect scenic beauty perceptions, consistent with zajonc and markus ( ), as well as acceptability ratings. different value orienta- tions do affect standards of aesthetic perception, just less so than they do for acceptability (see figure ). ribe / beauty versus acceptability © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com people who favor protection of ecological values require more positive levels of scenic beauty than others do to perceive acceptability (see figure ). these protectionists seem to be more emotionally reactive to negative scenic affects. because they see more scenic beauty than acceptability (see figure ), and see the lowest levels of scenic beauty and acceptability (see figure ), they may require that other more cognitively perceived environmental quali- ties (presumably related to perceptions of environmental health) be “added” to scenic beauty before landscapes are seen as more acceptable. among people favoring resource production from public lands, more beauty tends to mean more acceptable management, but all levels of scenic beauty and ugliness can garner perceptions of acceptable management (see figure ). these productionists are least inclined to perceive negative scenic affects as a consequence of the visual impacts of timber harvesting. productionists see differences in scenic beauty as others do, but aesthetics tends not to be a basis for disapproving of landscape conditions. for these constituents, scenic beauty can contribute to acceptable management but can also be “discounted” if their conceptions of good management are perceived, even if they substantially reduce scenic beauty. managers should be wary of any tendency (mccool et al., ) to adopt scenic beauty standards of acceptable management that are sufficient to sat- isfy constituencies or professionals who favor resource production. these relatively low beauty standards will likely be insufficient for many other con- stituencies to see landscape management as acceptable. managers should also not assume that they must always meet the high scenic beauty standards of acceptable management advocated by resource protection constituencies (magill, ). other constituencies will accept somewhat lower levels of beauty. planners and researchers seeking to ascertain the average acceptability of landscapes to the general public may use scenic beauty perceptions or assess- ments as a proxy for management acceptability. they should, however, ensure that their respondent sample or standards are taken from people not strongly committed to any ideological resource management agenda or that opposing agendas be equally represented in setting standards. the latter choice is obviously wiser in allowing all to be heard. this strategy may be appropriate because scenic beauty assessments can measure the strong and durable emotional perceptions that can serve as a primary basis for general public perceptions of management acceptability (as well as recreational enjoyment of public lands). if, instead, the perceptions of constituencies with strong agendas are of primary concern, planners and researchers must take care to measure the corresponding people’s views and not rely on general public–based assessments. environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com conclusions using aesthetic perceptions as a measure of the acceptability of landscape management would seem to oversimplify the complex and controversial. clearly, there is more that must be considered about acceptability than just aesthetic values. on the other hand, one must also be careful not to overtrivialize aesthetic perceptions. simple perceptions of scenic beauty can reflect basic emotional reactions to environments derived from ideals and psychological needs. these can then serve as a strong affective determinant of acceptability perceptions. when these affective responses derive from the same value perspectives, the result- ing scenic beauty and acceptability perceptions are nearly the same and a nontrivial proxy for each other. small but significant systematic differences between beauty and acceptability perceptions occur only when comparing people with substantially different resource management attitudes. simple perceptions of scenic beauty are also more robust than just emo- tional reactions. they can connote more cognitive dimensions inasmuch as they vary systematically and significantly between people with substantially different value perspectives in the same way that acceptability perceptions do. if one is aware of these differences and accounts for them (or discounts them through balanced or neutral sampling) in setting standards for land- scape assessments, then here too scenic beauty can be a fair measurement proxy for perceived acceptability of land management. the results from this study need replication for other landscape and land use types. they also need replication for other landscape planning problem contexts. studies in contexts where the public is not as well informed about management issues related to scenery content (as it was in this northern spot- ted owl controversy–derived study) might produce less remarkable differ- ences in perceptions. more studies of information effects on aesthetic versus cognitive perceptions are needed. studies are also needed regarding how landscape perceptions and people’s emotional stakes in scenic beauty influ- ence critical behaviors, such as political activism, voting, and recreational choices and satisfaction. references anderson, l. m. 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( ). perception of landscape and land use. in i. altman & j. f. wohlwill (eds.), human behavior and environment: advances in theory and research (vol. , pp. - ). new york: plenum. environment and behavior / november © sage publications. all rights reserved. not for commercial use or unauthorized distribution. at univ of oregon on april , http://eab.sagepub.comdownloaded from http://eab.sagepub.com the experience of beauty derived from sorrow the experience of beauty derived from sorrow tomohiro ishizu , * and semir zeki * wellcome laboratory of neurobiology, department of cell and developmental biology, university college london, london, united kingdom japan society for the promotion of science, tokyo, japan r r abstract: we studied the neural mechanisms that are engaged during the experience of beauty derived from sorrow and from joy, two experiences that share a common denominator (beauty) but are linked to opposite emotional valences. twenty subjects viewed and rerated, in a functional magnetic reso- nance imaging scanner, images which each had classified into the following four categories: beauti- ful and sad; beautiful and joyful; neutral; ugly. the medial orbito-frontal cortex (mofc) was active during the experience of both types of beauty. otherwise, the two experiences engaged different parts of the brain: joyful beauty engaged areas linked to positive emotions while sorrowful beauty engaged areas linked to negative experiences. separate regions of the cerebellum were engaged during experi- ence of the two conditions. a functional connectivity analysis indicated that the activity within the mofc was modulated by the supplementary motor area/middle cingulate cortex, known to be engaged during empathetic experiences provoked by other peoples’ sadness. hum brain mapp : – , . vc the authors human brain mapping published by wiley periodicals, inc. key words: aesthetic experience; emotion; functional magnetic resonance imaging r r you came to me to learn the pleasure of life and the pleasure of art. perhaps i was chosen to teach you something much more wonderful, the meaning of sorrow, and its beauty oscar wilde ( ), (in a letter to ‘bosie’, lord alfred douglas) introduction over the past few years, we and others have addressed the question of what neural mechanisms are engaged dur- ing aesthetic experiences, and especially during the experi- ence of beauty. in addressing the question, we were inspired by the question posed by the english art critic, clive bell. in his book art [ ], bell asked whether there is anything common to all objects that are experienced as beautiful or that arouse the aesthetic emotion. translating this into neural terms we, likewise, sought to understand whether there is a common brain system in which activity correlates with the experience of beauty. surprising though it may seem, although the experience of beauty derived from different sources entails activity in different areas of the brain, depending upon the source, there is one com- mon area, located in the medial orbito-frontal cortex (mofc) of the emotional brain, in which activity correlates parametrically with the experience of beauty, whether derived from sensory sources such as music or visual art [e.g., ishizu and zeki, ; kawabata and zeki, ], from moral sources [tsukiura and cabeza, ; wang et al., ] or from highly cognitive sources such as additional supporting information may be found in the online version of this article. contract grant sponsor: wellcome trust, london. tomohiro ishizu is currently at department of basic psychological research and research methods, university of vienna (tomohiro.ishizu@univie.ac.at). *correspondence to: tomohiro ishizu, gower street, london, wc e bt, united kingdom. e-mail: t.ishizu@ucl.ac.uk or semir zeki, gower street, london, wc e bt, united kingdom. e-mail: s.zeki@ucl.ac.uk received for publication august ; revised may ; accepted may . doi: . /hbm. published online may in wiley online library (wileyonli- nelibrary.com). r human brain mapping : – ( ) r vc the authors human brain mapping published by wiley periodicals, inc. this is an open access article under the terms of the creative commons attribution license, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. http://orcid.org/ - - - x http://creativecommons.org/licenses/by/ . / mathematics [zeki et al., ]. in the work reported here, we were inspired by the quote from oscar wilde given above, to explore the neural activity that correlates with the experience of beauty derived from sorrow. the quote implies that sorrowful beauty belongs in a separate, or separable, category, which can be defined as the experi- ence of a positive (aesthetic) emotion with a negative com- ponent, that of sadness. to study the neural correlate of such an experience, we had to incorporate another distinct category—that of beauty aroused from joy, which can be categorised as a positive emotion with a positive compo- nent—for comparison. important though the distinction between sorrowful and joyful beauty is, it is one that is not often made, or not made emphatically enough. this is surprising because the distinction is easily recognized and experienced by most, even if both categories arouse the aesthetic emotion. in sculpture, for example, michelangelo’s great piet�a in rome is suffused with pathos, tenderness and sadness, whereas the three graces of canova are joyful and playful. in music, the waltzes of johann strauss are light-hearted and engaging while the adagio from beethoven’s ninth sym- phony is permeated with contemplative sorrow. the list is endless and includes works in literature, poetry, dance, and theatre. photography, especially, has provided many examples that can be easily classified emotionally by any viewer as sorrowful or joyful, with beauty as their com- mon denominator; good examples are dorothea lange’s iconic images of the great depression, and especially the migrant mother, on the one hand and bill brandt’s east end girl dancing on the other. aside from beauty, these two separate categories share another common denomina- tor, empathy, which makes it possible for humans to become aware of the feelings of others and indeed experi- ence those same feelings—whether of joy or sorrow—to varying degrees. it seemed to us that this distinction provides fertile ground for a neurobiological enquiry into the brain mecha- nisms that are engaged when two contrasting affective states, a negative one (sorrow) and a positive one (joy) both result in the experience of beauty. this enquiry paral- lels, in a sense, our previous enquiry into the distinction, in neural terms, between the sublime and the beautiful, two categories that have been discussed much more exten- sively in philosophies of aesthetics. the common descrip- tion of the sublime as containing a negative affect (‘pleasure from displeasure’ or ‘beauty mingled with hor- ror’) is reflected in a pattern of brain activity that is differ- ent from that which is engaged during the experience of the beautiful [ishizu and zeki, ]. this made it interest- ing to enquire whether we can also detect differences in the pattern of brain activity during aesthetic experiences derived from two opposite states. our general hypothesis was that there would be profound differences with the two experiences but that, given the pre-eminence of activ- ity in the mofc during the experience of the beautiful, the latter would be active in both states, even in spite of the evident differences between the two. moreover, since experiencing beauty derived from positively or negatively valenced emotion inevitably requires mentalizing others’ emotional states or interpreting their intentions, empathy is another common denominator to the experience of beauty in sorrowful and joyful sources. we, thus, expected to find activity in brain regions which past studies have implicated in empathetic experiences. materials and methods participants twenty one healthy right-handed volunteers ( females; males; mean age, . years) from different cultures and ethnic backgrounds ( taiwanese, indian, japanese, middle eastern, and west and north euro- peans) participated but data from one volunteer was excluded because of excessive noise during scanning, leav- ing us with volunteers; all had normal or corrected-to- normal vision, and none had a history of neurological or psychiatric disorder. written informed consent was obtained from all and the study was approved by the ethics committee of university college london, and con- formed to the code of ethics of the world medical associ- ation (declaration of helsinki). all data were anonymized. preliminary psychophysical testing and postscanning ratings although pictures depicting war scenes, weapons, vio- lence or strong political, and religious attributes may often be deemed sorrowful or beautiful, we excluded them from this study because it is known that viewing scenes depict- ing violence, or which remind viewers of violence, can induce immediate brain responses, such as activity within frontal and limbic system, even when viewed passively (e.g., kelly et al., ]; we wanted to exclude such auto- matic brain responses which are unrelated to the current task. we, therefore, used instead pictures of events like funerals, abandoned children and buildings, and sad faces, as well as landscapes and daily scenes, in both mono- chrome and in color. the pictures that we used were drawn from photographic magazines and books, including the family of man (in which the photographs referred to in the introduction can be found), the modern century, and the great life photographers. during a first visit to the laboratory, between and days prior to scanning, each subject was instructed about the experiment and, in a psychophysical test, rated the stimuli according to their aesthetic and emotional valence through two questionnaires. in the aesthetic evaluation, participants classified a picture into five groups according to the intensity of the aesthetic experience aroused in them, using a likert scale extending from (‘very r ishizu and zeki r r r beautiful’) to (very ugly), with being ‘neutral’; in the emotional evaluation, corresponded to ‘very joyful’, to ‘neutral’, and to ‘very sorrowful’. thus, we obtained, for each subject, an emotional and an aesthetic rating for each of the stimuli. participants gave the aesthetic and the emotional ratings in counterbalanced order. it should be noted that they were instructed to give emotional ratings according to the feelings that they experienced when view- ing the images, not to those of what people in the images might feel. each stimulus remained on the computer screen until participants responded to the second evaluation, after which an inter-trial interval of s followed; they were then asked to press a button as soon as possible after they had made their evaluation and were also asked to indicate their familiarity with each picture (‘have you seen this pic- ture before?’) and familiar pictures were excluded. from these rated pictures, we selected, for each sub- ject, which fell into the four categories of ‘sorrowful beauty’, ‘joyful beauty’, ‘neutral’, and ‘ugly’. pictures fall- ing into the sorrowful beauty category were the ones that had been given a rating of on the emotional score and on the aesthetic score; pictures falling into the joyful beauty category had a rating of on the emotional scale and on the aesthetic scale while those rated as neutral had on both scales. stimuli rated as ugly had a score of (neutral) for the emotional rating and for the aesthetic score (see fig. ). each of the four categories had stim- uli, making a total of stimuli which each participant viewed in the scanner. we excluded five participants out of twenty-six after the preliminary psychophysical tests showed that they did not have sufficient trials for each of the four categories. the detailed behavioral data obtained in the preliminary psychophysics are found in supporting information. during the scanning session, participants were asked to rerate each picture aesthetically, after viewing it, but this time on a scale of to (beautiful, neutral, ugly). immedi- ately after scanning, they rerated the stimuli (which were presented in the same order as in the scanner) for their emotional valence, using a -point likert scale ( as joyful, as neutral, as sorrowful). paradigm and procedure stimuli were generated using cogent (http:// www.vislab.ucl.ac.uk/cogent_ .php) running in mat- lab (mathworks, natick, ma); they were back-projected onto a screen using an lcd projector, through an angled mirror. the resolution of the screen was , , pix- els; the height of each stimulus was while the width varied. the session began with subjects viewing a flat black screen for s to allow for t equilibration effects to sub- side (the corresponding first six brain volumes were dis- carded). after this s blank period, an instruction about the aesthetic judgment appeared on the screen, to inform participants that a session had started. a fixation point then appeared at the centre of the screen for s against a black background, after which visual stimuli were pre- sented in a pseudorandom order for s. we had images in each of the four experimental conditions, mak- ing images in total. we had six functional scanning sessions for each subject. each functional session had trials. to make a set of images, we selected images randomly out of from each of the experimental condi- tions so that each condition had the same number of trials through a functional session. after this procedure, we ran- domized the sequence of stimulus presentation within a functional scanning. the stimulus presentation was fol- lowed by an interval with a jitter of – s, during which participants gave their aesthetic ratings. following each stimulus presentation, participants were asked to rate it on a -point likert scale, by pressing one of three buttons with their right index, middle or ring fin- ger. the response period lasted – s and participants could make their rating at any time during that period; it ended with a blank period of s, during which the scan- ner continued to acquire blood-oxygen-level dependent (bold) signals. the stimuli were presented in six sessions. each session consisted of stimuli with a s resting period between the first and the last trials during which participants were instructed not to close their eyes. prior figure . preliminary behavioral data summed over subjects. frequency distribution of beauty rating (x axis) versus emotion rating (y axis). size of each circle is proportional to the number of trials for that rating. r experience of sorrowful beauty r r r http://www.vislab.ucl.ac.uk/cogent_ http://www.vislab.ucl.ac.uk/cogent_ http://.php to the scanning, participants had a short practice session with a different set of visual stimuli to those used in the scanning session. functional magnetic resonance imaging scanning scanning data were acquired in a -t siemens magne- tom trio magnetic resonance imaging scanner (siemens, erlangen, germany) fitted with a -channel head-coil. an echo-planar imaging (epi) sequence was applied for func- tional scans to obtain bold signals (echo time, ms; repeat time, . s), using slices to cover the whole brain. the voxel resolution was -mm in-plane resolu- tion, with a mm slice thickness and -mm inter-slice gap. magnetic resonance imaging signal losses in the orbi- tofrontal cortex (ofc) and amygdala were reduced by applying a z shim gradient moment and slice tilt [weis- kopf et al., ]. t -weighted anatomical images were acquired at the end of the experimental sessions for each subject ( slices; resolution, mm; echo time, . ms; repeat time, . ms). field maps were also acquired with the siemens standard gradient-echo field map sequence to correct for geometric distortion of epi images [hutton et al., ]. we also recorded the heart and respiration rates for each subject. functional magnetic resonance imaging data analysis all data were analysed with spm (statistical parametric mapping, http://www.fil.ion.ucl.ac.uk/spm/software/ spm /). the epi images for each subject were realigned and normalized into montreal neurological institute (mni) space, smoothed with a gaussian smoothing kernel of mm, and filtered with a high-pass cut-off ( s) to remove drift terms. the stimulus for each subject was modelled as a set of regressors in a general linear model first-level (within subject) analysis. the experiment was a block design, and boxcar functions were used to define the stimulations; these modelled the onsets and durations of the visual stimuli. head movement parame- ters calculated from the realignment preprocessing step, physiological recordings, and response periods were included as regressors of no interest. stimulus functions were convolved with a canonical haemodynamic response function. contrast images were taken to random-effects second-level (between subject) analyses to produce statisti- cal maps at the group level. to carry out categorical contrast analyses according to the intensity of the aesthetic and emotional experience, rat- ings were coded as , , for ‘ugly’, ‘neutral’, and ‘beauti- ful’, and , , and for ‘sorrowful’, ‘neutral’, and ‘joyful’. we then categorized stimuli rated in the aesthetic rating and in the emotional rating into ‘joyful beauty’, those rated and into ‘sorrowful beauty’, those rated and into ‘neutral’ and those rated and as ‘ugly’. roi analysis since, we hypothesised the involvement of the mofc during the experience of both sorrowful and joyful beauty, we constructed a region-of-interest (roi) in the mofc centered on the coordinates at which activity was found in previous studies to correlate with the experience of beauty derived from visual sources, field a (– ) [ishizu and zeki, ], to learn whether activity there also corre- lates with the experience of two differently valenced emo- tions which have beauty as a common denominator. we created a roi mask with -mm sphere to extract average contrast estimates from the mofc roi across subjects. we then compared activity within this region between sorrow- ful beauty > ugliness, as well as joyful beauty > ugliness, against zero, to learn whether mofc was active with both types of beauty experience. we also compared these two contrasts directly to learn whether the strength of activity differed significantly during the experience of the two emotionally distinct kinds of beauty. whole brain analysis we also conducted whole brain categorical analyses to chart brain activations unique to joyful beauty and sorrow- ful beauty separately, using the contrasts of sorrowful beau- ty > ugliness and joyful beauty > ugliness, respectively. to characterize common brain responses involved in the above two contrasts, we conducted a conjunction analysis performed by a test for independently significant effects as in a logical and ([sorrowful beauty > ugliness] \ [joyful beauty > ugliness]) based on the minimum statistic [nichols et al., ]. since we had an a priori assumption of the involvement of the mofc in the experience of beauty [e.g., ishizu and zeki, , ], we used a small volume correc- tion (svc) on the mofc with a mm sphere centred on coordinates (– ), taken from ishizu and zeki [ ]. functional connectivity analysis in addition to the regional activity analyses, we also studied the functional connectivity between mofc and other brain regions to determine the contribution that the latter may make to modulating mofc activity as a func- tion of the aesthetic and emotional valence of the stimulus, either through input to it or output from it. for this, we performed a psychophysiological interaction (ppi) [friston et al., ]; this tests which regions show activation pat- terns that co-vary with mofc activity, when stimuli are rated as joyfully (or sorrowfully) beautiful or ugly. we assessed changes in functional connectivity between the seed region in the mofc and other brain regions in two contrasts: joyful beauty > ugliness and sorrowful r ishizu and zeki r r r http://www.fil.ion.ucl.ac.uk/spm/software/spm http://www.fil.ion.ucl.ac.uk/spm/software/spm beauty > ugliness; the analysis for each was performed sep- arately. the ppi employed a design matrix consisting of three regressors representing ( ) the extracted time-series of neural activity within an -mm spherical region centred on the mofc (‘physiological variable’); ( ) a second regressor representing the psychological context of interest, that is, joyful beauty > ugliness and sorrowful beauty > ugliness (‘psychological variables’); ( ) a third regressor representing the interaction of the two previous variables (i.e., the interac- tion between the psychological and physiological variables - ‘ppi term’). head-movement parameters were also included in the model as regressors of no interest. this enabled us to identify areas in which the correlation in bold activity with the mofc seed region increases during trials in which a participant experienced sorrowful (or joyful) beauty rela- tive to those during which they experienced ugliness. the ppi was carried out separately for each subject and entered into random-effects group level analysis. to obtain the data for the physiological variable, we de-convolved the time- series of neural activity from the -mm roi within the mofc, centred on the coordinates of subject-specific activa- tions in the region. thus, to define the roi, we used the con- trast (joyful beauty sorrowful beauty) > ugliness to locate the closest local maximum to the coordinates [ ] which we obtained in the group-level analysis. the results of this analysis are displayed in table i and figure . it should be noted that, although we selected the mofc as the seed region, the ppi cannot determine directly the direction- ality of the connectivity or the interaction between the seed region and other brain regions; our discussion is, therefore, limited to interactions between the mofc and functionally connected regions without specifying their polarity. we report cluster level activations significant at p < . family-wise error (fwe) corrected, although some of these (indicated in the table) were also significant at the peak level at p < . fwe corrected. the coordinates of all acti- vations are reported in mni space. results behavioral results ideally, the status of the ratings given to the stimuli viewed in the scanner should be the same as that given dur- ing the preliminary viewing test, that is, each condition (e.g., beautiful and sorrowful) should appear times. in reality, such an ideal situation was not reached. based on the aes- thetic ratings given during the scanning sessions and the postscanning emotional ratings, we obtained the following ratings over participants: . for ‘joyful beauty’ ( – ), . for ‘sorrowful beauty’ ( – ), . for ‘neutral’ ( – ), and . for ‘ugliness’ ( – ) (fig. ), on average. these slight var- iations in the ratings during the preliminary tests and dur- ing the scanning functional magnetic resonance imaging (fmri) session are not of great concern since there was a rea- sonably distributed number of trials in each condition. the stimuli consisted of pictures of a face(s), people including faces, and landscapes without human figures. figure shows details of the number of images in terms of stimulus contents. it is known that viewing different types of visual stimuli, for example, faces versus scenes, results in activa- tion of different brain areas, reflecting the functional special- ization of the visual brain [kawabata and zeki, ; zeki et al., ]. all four experimental conditions in this study, however, had similar proportions of images belonging to the different categories, that is, human figures (including faces and people) and landscapes (see fig. ). the most prevalent stimulus images we had for each subject con- tained human figures, that is, people or faces ( . % on average ( . – . %) across the experimental conditions), whereas, very few consisted of scenes without a human fig- ure ( . % on average ( . – . %)). we conducted a -way analysis of variance with stimulus contents (human figure, landscape) and response conditions (joyful beauty, sad beauty, neutral, ugliness). there was no significant differ- ence in response conditions and interactions, while a main effect of stimulus contents alone was observed (df , f , , p < . ). therefore, the brain responses found by contrasting the conditions we report here cannot be explained by differences in stimulus contents. neuroimaging results mofc to learn whether there was a difference in the strength of activity within the mofc between the experience of sorrow- ful and joyful beauty, we extracted, for each subject, the con- trast estimates within the defined roi in the mofc and compared across conditions. first, one sample t-tests revealed that the extracted averaged contrasts estimates for ‘sorrowful beauty’ and ‘joyful beauty’, both against ‘ugli- ness’, were different from zero (sorrowful beauty, t . , df , p < . ; joyful beauty, t . , df , p < . ), showing that, as we expected, the mofc is engaged during the experience of both joyful beauty and sorrowful beauty. this area has been reported to be active in previous studies on aesthetic experiences using a variety of stimuli [ishizu and zeki, ; kawabata and zeki, ; o’doherty et al., ; tsukiura and cabeza, ; zeki et al., ]. a direct comparison between the two conditions showed, however, that the averaged contrast estimates for joyful beauty gave higher values than that for sorrowful beauty (paired t-test, t . , df , p < . ) (fig. ). in short, the roi results suggest that the mofc is com- monly activated with the experience of beauty but that the strength of the activation may be modulated by the valenced emotions. whole brain contrasts our main aim was to learn whether the brain regions previously reported as active during the experience of r experience of sorrowful beauty r r r t a b l e i. l o c a ti o n , m n i c o o r d in a te s , c lu s te r s iz e a n d v a lu e s fo r th e a c ti v a ti o n s p r o d u c e d b y th e c a te g o r ic a l c o n tr a s ts o f s o r r o w fu l b e a u ty > u g li n e s s , jo y fu l b e a u ty > u g li n e s s , s o r r o w fu l b e a u ty > jo y fu l b e a u ty , jo y fu l b e a u ty > s o r r o w fu l b e a u ty , a n d b y th e c o n ju n c ti o n a n a ly s is s o r r o w fu l b e a u ty > u g li n e s s \ jo y fu l b e a u ty > u g li n e s s c lu st e r p (f w e -c o r) p (f d r -c o r) e q u iv k p (u n c) p e a k p (f w e -c o r) p (f d r -c o r) t e q u iv z p (u n c) x y z (m m ) c a te g o ri ca l co n tr a st s: s o rr o w fu l b e a u ty > u g li n e ss . . . . . . . . r m f g . . . . . if g . . . . . d ip f c . . . . . . . . l c a u d a te . . . . . p c c . . . . . . . . . . . . . r c e re b e ru m (l o b u le v i) . . . . . . . . . . . . . . . . . . r d a c c . . . . . jo y fu l b e a u ty > u g li n e ss . . . . . . . . l h ip p o ca m p u s . . . . . c a u d a te . . . . . h ip p o ca m p u s . . . . . . . . r p g a c c . . . . . . . . . . . . . . . . . . l c e re b e ll u m (l o b u le v ii ) . . . . . . . . . . . . . r c e re b e ll u m (l o b u le v ii . . . . . . . . . . . . . . . . . . l m o f c . . . . . . . . . . . . . . . . . . . . . . . l ra c c s o rr o w fu l b e a u ty > jo y fu l b e a u ty . . . . . . . . l s p l . . . . . ip l . . . . . p re cu n e u s . . . . . . . . r m f g . . . . . . . . . . . . . . . . . . l m f g . . . . . . . . . . r ishizu and zeki r r r t a b l e i. (c o n ti n u e d ). c lu st e r p (f w e -c o r) p (f d r -c o r) e q u iv k p (u n c) p e a k p (f w e -c o r) p (f d r -c o r) t e q u iv z p (u n c) x y z (m m ) jo y fu l b e a u ty > s o rr o w fu l b e a u ty . . . . . . . . r t p j/ s m g c o n ju n ct io n ([ jo y fu l b e a u ty > u g li n e ss ] \ [s a d b e a u ty > u g li n e ss ]) . [s v c , ] . l (m o f c )] . . . . . . l c e re b e ll u m v ii . . . . . . . . l m o f c . . . . . p p is : m o f c _ s o rr o w fu l b e a u ty > u g li n e ss . . , . . . . . . r m id d le o cc ip it a l g y ru s . . . . . l in g u a l g y ru s . . . . . . . . . . . . . l s m a (e n cr o a ch in g to m c c ) . . . . . . . . . . [s v c , ’ (d ip f c )] . . . . . . . . r d ip f c / m f g m o f c _ jo y fu l b e a u ty > u g li n e ss . . . . . . . . r m t g . . . . . . . . . . . . . . . . . . l rm p f c . . . . . . . . . . . . . . . . . . l o cc ip it a l g y ru s . . . . . . . . . . | . . . . . . . . l p re ce n tr a l g y ru s . . . . . . . . . . a ls o sh o w n a re a re a s e x h ib it in g g re a te r fu n ct io n a l co n n e ct iv it y w it h th e m o f c in p sy ch o p h y si o lo g ic a l in te ra ct io n s (p p is ), in th e co n tr a st s so rr o w fu l b e a u ty > u g li n e ss a n d jo y fu l b e a u ty > u g li n e ss . r experience of sorrowful beauty r r r beauty, and in particular the mofc, were differentially engaged during the experience of sorrowful and joyful beauty. but we were also interested in learning whether, besides the mofc, significantly different brain regions were involved when the experience was that of sorrowful as opposed to joyful beauty, especially given that the two arouse different empathetic feelings. to chart brain activations that correlate with the experi- ence of sorrowful and joyful beauty, we performed separate categorical contrasts of ( ) sorrowful beauty > ugliness, and of joyful beauty > ugliness; we also contrasted the activity produced by ( ) joyful beauty versus sorrowful beauty, to directly compare brain regions that are uniquely active dur- ing each kind of aesthetic experience. we then used a con- junction analysis [nichols, et al., ] to characterize brain activations common to both sorrowful and joyful beauty using the contrast [sorrowful beauty > ugliness] \ [joyful beauty > ugliness]. all activations are listed in table i. sorrowful beauty versus ugliness. the contrast sorrowful beauty > ugliness resulted in activity in lateral frontal lobe including the middle frontal gyrus (mfg); this band of activity extended to the inferior frontal gyrus (ifg) and the dorso-lateral prefrontal cortex (dlpfc). the posterior cingulate cortex (pcc), encroaching upon the caudate figure . behavioral data collected in the fmri experiment, showing aver- aged number of trials with each kind of stimulus (people, faces, and landscape without a human figure), with standard deviations for each of the four experimental conditions across subjects. figure . the upper panel shows the activation within the medial orbitofron- tal cortex correlating with the experience of joyful and sorrowful beauty. statistical parametric maps rendered onto canonical ana- tomical sections showing the t-statistic for (left) joyful beauty > ugli- ness, (middle) sorrowful beauty > ugliness, and (right) the results of a conjunction analysis for joyful beauty > ugliness \ sorrowful beauty > ugliness. random effects analysis with subjects. display threshold p < . (uncorrected). (lower right) region of interest in the mofc. (lower left) averaged contrast estimates for the contrasts joyful beauty > ugliness (jb > ug) and sorrowful beau- ty > ugliness (sb > ug) within the defined roi (– ), over subjects. joyful beauty caused a higher bold signal than sor- rowful beauty. * p < . . error bars are standard error (se). [color figure can be viewed at wileyonlinelibrary.com] r ishizu and zeki r r r http://wileyonlinelibrary.com (head and body), was also active. in addition, there was activity in parts of the cerebellum (lobule vi) and dorsal acc (see figs. , , and ). in short, some cortical regions which previous studies had found to be active during sorrowful experiences were also active in the contrast of sorrowful beauty versus ugliness. joyful beauty versus ugliness. the contrast joyful beauty > ugliness led to activation in the right mofc, in a region adjoining rostro-ventral anterior cingulate cortex (acc); this entire zone has been reported to be active in previous studies of aesthetic experiences [e.g., ishizu and zeki, ; tsukiura and cabeza, ; zeki et al., ]. the body of the right caudate nucleus and pregenual acc (pgacc), which have been found to be active in the expe- rience of visual beauty and aesthetic and evaluative judg- ments [cunningham et al., ; ishizu and zeki, ; jacobsen et al., ; vartanian and goel, ], were also active. in addition, there were activations in bilateral pos- terior hippocampus and parts of the cerebellum (lobule vii crus i and ii) (see figs. , , and ). in short, in addition to the activation within the mofc, we observed a similar pattern of cortical and subcortical activations in the contrast of joyful beauty versus ugliness to that reported in previous studies of visual beauty. areas uniquely active for each kind of beauty. the con- trast sorrowful > joyful beauty produced activation in: the left inferior parietal lobe (ipl) encroaching on the precu- neus, a region which has often been observed in studies of emotional/social pain (e.g., lamm et al., ); it also pro- duced activity in bilateral mfg, parts of which have been found to be involved during emotional states [acevedo et al., ; sabatinelli et al., ]. the reverse contrast, of joyful > sorrowful beauty led to activation in the right temporoparietal junction (tpj), including the supramarginal gyrus (smg), a region thought to be involved in controlling empathy toward others [e.g., silani et al., ] (fig. ). in summary, the experience of joyful and sorrowful beauty had, as correlates, distinct patterns of cortical activ- ity. the former included the tpj and the smg alone while the latter included the left parietal lobe, the precuneus, and bilateral mfg. areas commonly active during the experience of both types of beauty. the conjunction analysis ([sorrowful beau- ty > ugliness] \ [joyful beauty > ugliness]) showed com- mon activation in the mofc with the application of svc, and left cerebellum (lobule vii), whereas the acc, which figure . sites active during the experience of sorrowful beauty. statistical parametric maps rendered onto canonical anatomical sections showing the t-statistic for the contrast sorrowful beauty > ugli- ness. random effects analysis with subjects. display threshold p < . (uncorrected). abbreviations: ifg, frontal gyrus; mfg, middle frontal gyrus; dacc, dorsal anterior cingulate cortex; pcc, posterior cingulate cortex. [color figure can be viewed at wileyonlinelibrary.com] figure . sites active during the experience of joyful beauty. statistical parametric maps rendered onto canonical anatomical sections showing the t-statistic for the contrast joyful beauty > ugliness. random effects analysis with subjects. display threshold p < . (uncorrected). abbreviation: dacc, dorsal anterior cingulate cortex. [color figure can be viewed at wileyonlineli- brary.com] r experience of sorrowful beauty r r r http://wileyonlinelibrary.com http://wileyonlinelibrary.com http://wileyonlinelibrary.com was active in both conditions, did not survive this thresh- old in the conjunction analysis (fig. ). functional connectivity the conjunction analysis revealed that the mofc is engaged during the experience of both sorrowful and joy- ful beauty. we undertook a ppi analysis to learn more about the possible differential neural engagements during the experience of the two types of beauty, by examining the functional connectivity between the mofc and other brain regions. because the stimuli experienced as being sorrowful contained, for the most part, pitiful and empa- thetic scenes (such as pictures of funerals, an abandoned child, a crying man, separations, etc.), we expected that, in this condition, the mofc will show greater functional con- nectivity with regions related to the experience of sad (negative) emotional empathy and the interpretation of others’ intentions, especially under sad or painful situa- tions (‘negative empathy’ as opposed to ‘positive empathy’ [morelli et al., ]); these regions are the middle cingu- late cortex (mcc), the supplementary motor area (sma) [fan et al., ], and the dlpfc [lieberman, for a review; weissman et al., ]. using sorrowful beauty and ugliness as the psychological parameters, we tested whether the physiological coupling between mofc, as the seed region, and other regions besides the ones mentioned above, would change between the experience of sorrowful beauty and ugliness. the results showed that there was indeed increased functional connectivity between the mofc and sma, encroaching onto mcc, and several other regions (see fig. and table i). with the application of svc using the coordinates based on a previous ppi study in the bilateral dlpfc [kirk et al., ], dlpfc also showed a significant increased connectivity with the mofc during the experience of sorrowful beauty. we then compared the averaged b-value in the sma/mcc during the experience of sorrowful and joyful beauty and found a stronger connectivity between the sma/mcc and the mofc in sorrowful beauty relative to joyful beauty (t( ) . , p < . ). in contrast, the experience of joyful beauty produced increased functional connectivity between the mofc and the anterior rostral medial prefrontal cortex (anterior rmpfc) and middle temporal gyrus (mtg), among several other regions (see table i). the averaged b-value in the rmpfc showed stronger connectivity in joyful beauty than sorrowful beauty (t( ) . , p < . ). all other ppi results are listed in table i. discussion the experience of beauty may, in general terms, be regarded as a positive, rewarding, and pleasurable one. it is perhaps not surprising, therefore, that regardless of source, it correlates with activity in field a of mofc [ish- izu and zeki, ], a region of the emotional brain which has been generally associated with pleasure and reward (e.g., o’doherty et al., ); activity in it has been shown to correlate parametrically with the declared intensity of the experience of beauty derived from a variety of stimuli, such as faces, colors, motion, paintings, music, architec- tures, moral judgments, and mathematical equations [ikeda et al., ; ishizu and zeki, ; kawabata and zeki, ; kuhn and gallinat, ; o’doherty et al., ; zeki and stutters, ; tsukiura and cabeza, ; vartanian et al., for a meta-analysis; zeki et al., ] though apparently not from the performing (dance) arts [e.g., calvo-merino, et al., ; cross et al., ]. more- over, a recent study has reported an increase in aesthetic ratings of visual stimuli [nakamura and kawabata, ] following the application of anodal transcranial direct cur- rent stimulation to the mofc, presumably because of enhanced neural activity within it. in the work reported here, we wanted to go a step beyond and enquire into whether the experience of beauty linked to different and indeed opposite emotional states would also correlate with activity in a of mofc. sorrow- ful beauty is commonly associated with negative empathy figure . sites revealed to be active in the contrast sorrowful versus joy- ful beauty. statistical parametric maps rendered onto canonical anatomical sections showing the t-statistic for (upper) the con- trasts joyful beauty > sorrowful beauty and (lower) sorrowful beauty > joyful beauty. random effects analysis with subjects. display threshold p < . (uncorrected). abbreviations: rtpj, right temporoparietal junction; ipl, inferior parietal lobe; spl, superior parietal lobe; mfg, middle frontal gyrus. [color figure can be viewed at wileyonlinelibrary.com] r ishizu and zeki r r r http://wileyonlinelibrary.com while joyful beauty is linked to positive empathy. the two experiences studied here are, thus, associated with oppo- site empathetic sources but share a common denominator, that of beauty. given that field a of mofc correlates with the experience of beauty regardless of source, it was natural to hypothesize that the experience of beauty linked to emotional states of opposite valence would also corre- late with activity in the same area, which is indeed what we found. but the intensity of activity in a of mofc (defined as the roi) was greater during the experience of beauty derived from joy than that derived from sorrow. this made it interesting to enquire into the strength of connectivity between the mofc and areas of the brain that have been associated with experience of two opposite states of empathy. negative and positive empathy reflected in the pattern of brain activity empathy has been studied in fair detail recently but most do not refer explicitly to a distinction between nega- tive and positive empathy. that the two are separate is, of course, a common human experience; it is reflected here in the distinct patterns of activation that correlate with the experience of sorrowful and joyful beauty, besides the common correlate in activity of a of mofc. this distinc- tion can be discerned in (a) the general pattern of cortical activity, (b) in activity within the anterior cingulate cortex, and (c) in the cerebellum. a. general cortical activation patterns. contrasting the pat- tern produced by the experience of sorrowful beauty with that produced by the experience of ugliness resulted in an extensive pattern of activity that includes, in addition to the reward-related regions, bilateral mfg, extending to ifg, right dlpfc and pcc; all three areas are known to be active when empathizing with others, especially in nega- tive emotional conditions. the ifg, in particular, has been reported to be active during listening to minor chords (rated as sad and indicative of sorrow) compared to major ones (which were rated as ‘happy’), even though both were rated as aesthetically beautiful by the subjects [suzuki et al., ]. this region has also been reported to be active when viewing pictures of humans suffering from harm and threat [nummenmaa et al., ], while the mfg has been reported to be active during the viewing of sad faces [acevedo et al., ; sabatinelli et al., ]. the dlpfc has been linked to handling complex social situa- tions [lieberman, for a review; weissman et al., ], control of emotional states [goldin et al., ; keightley et al., ], inferring others’ intentions, and the- ory of mind [guroglu et al., ]. the pcc, encroaching upon the caudate (head and body), was also active; this region has been implicated in a range of functions includ- ing the experience of high valence emotional stimuli [mad- dock et al., ], theory of mind [fletcher et al., ; greene et al., ], and sad autobiographical recall [farrow et al., ; maddock, ]. activity in the ipl, also observed with the experience of sorrowful beauty when contrasted with joyful beauty, has been associated with emotional or social pain and, together with the ifg, has been considered as constituting an ‘emotion contagion network’ underlying our ability to empathize emotionally [shamay-tsoory, ], though negatively. by contrast, the experience of joyful beauty correlated with activity in the right tpj and in the smg, both of which have been considered to be involved in controlling empathy toward others, by overriding an emphasis on the self (ego-centricity) [e.g., silani et al., ]. activity in the tpj, which has been considered to play an important role in interpersonal emotional and cognitive interactions [saxe, , for a review], has been reported to increase when subjects view happy faces compared to angry or dis- appointed ones [lelieveld et al., ] and both tpj and smg have been demonstrated to be part of a larger corti- cal zone, which includes the right parietal area, that is active when adopting other peoples’ emotional states [e.g., ruby and decety, ]. b. anterior cingulate cortex: activation within the acc found during the experience of sorrowful and joyful beauty can be separated into dorsal (dacc) for the former and the pregenual subdivision (pgacc) for the latter (see fig. ). it has been suggested that the dacc is active dur- ing the experience of emotionally distressing conditions figure . sites active within the acc during the experience of sorrowful and joyful beauty. statistical parametric maps rendered onto canonical anatomical sections showing the t-statistic for (red) the contrasts joyful beauty > ugliness and (blue) sorrowful beau- ty > ugliness. random effects analysis with subjects. display threshold p < . (uncorrected). abbreviations: dacc, dorsal anterior cingulate cortex; pgacc, perigenual anterior cingulate cortex. [color figure can be viewed at wileyonlinelibrary.com] r experience of sorrowful beauty r r r http://wileyonlinelibrary.com such as physical and social pain (acknowledging others’ pain) [eisenberger and lieberman, ; lamm et al., for a review], whereas the pgacc activity (including activity in the adjacent subgenual acc and mofc/ven- tromedial prefrontal cortex (vmpfc)) correlates with the experience of positive emotions [etkin et al., for a review]. a previous study reports activity in this region when viewing aesthetically pleasing stimuli [e.g., varta- nian et al., ]. acc’s diverse cognitive and emotional functions make it difficult to define each subdivision’s involvement in a precise function. but previous studies suggest that the ventral and sub/pregenual areas are involved in processing of emotion, especially positive emo- tion while the dorsal subdivision, by contrast, is strongly associated with negative emotional states as well as cogni- tive components. this separation, again, reflects anatomi- cally the involvement of separate regions in positive and negative components of aesthetic experiences. c. cerebellum: the dichotomy in neural activity that cor- relates with the two contrasting experiences is also reflected in cerebellar activity. we found that the experi- ence of sorrowful and joyful beauty engaged different parts of the cerebellum, lobule vi for sorrowful beauty and lobule vii for joyful beauty (see fig. ). although there is no current consensus regarding the pattern of cer- ebellar activity during aesthetic experiences, several past studies have reported activity in cerebellum during aes- thetic experiences, including ones derived from visual and literary beauty as well as during the judgment of beauty [bohrn et al., ; ishizu and zeki, ; vartanian and goel, ]. it is noteworthy that sorrowful beauty engaged lobule vi, which past studies have shown to be more responsive to negatively charged stimuli such as sad- ness, fear, and anger than to positive ones [baumann and figure . sites active within the cerebellum during the experience of sor- rowful and joyful beauty. statistical parametric maps rendered onto canonical anatomical sections showing the t-statistic for (red) the contrasts joyful beauty > ugliness and (blue) sorrowful beauty > ugliness. random effects analysis with subjects. dis- play threshold p < . (uncorrected). [color figure can be viewed at wileyonlinelibrary.com] figure . the upper panel shows the functional connectivity observed in this study, with the mofc as the seed region. areas in orange (anterior rmpfc) showed greater functional connectivity with the mofc during the experience of joyful beauty, whereas areas shown in blue (sma/mcc) showed greater connectivity during the experience of sorrowful beauty. display threshold p < . (uncorrected). lower panel (left) shows the averaged beta- estimates measuring the correlation between bold activity in the sma/mcc and the mofc. lower panel (right) shows the averaged beta-estimates measuring the correlation between bold activity in the anterior rmpfc and the mofc. blue bars denote the averaged beta-estimates with sorrowful beauty and red bars denote those with joyful beauty. error bars are stan- dard error (se). abbreviations: sma, supplementary motor area; mcc, middle cingulate cortex; rmpfc, rostral medial prefrontal cortex; mofc, medial orbito-frontal cortex. [color figure can be viewed at wileyonlinelibrary.com] r ishizu and zeki r r r http://wileyonlinelibrary.com http://wileyonlinelibrary.com mattingley, ; park et al., ] and to perspective tak- ing to others’ pain [lamm et al., ], which can be regarded as negative empathy in the context of the current study. although the cerebellum is, in general, more active during what may be regarded as negative emotions [stoodley, ], crus ii (lobule vii) has been reported to be more strongly engaged when viewing pictures repre- senting happiness than disgust [schienle and scharmuller, ] and is uniquely active with joyful beauty in the cur- rent experiment. patient studies have suggested that lesions in lobule vi and vii can lead to cerebellar cognitive affective syn- drome, when patients suffer from various emotional and behavioral deficits, including flattening of emotions or impulsive behaviors [schmahmann, ; schmahmann et al., ]. it has been suggested that those deficits in emotion, possibly produced by disrupting the cerebellar- limbic connection [stoodley and schmahmann, ], can affect the ability to communicate and empathize with the perspectives of others [oberman and ramachandran, ]. hence, both cortical and cerebellar activations reflect, in a sense, the common human experience which can sepa- rate sorrowful from joyful beauty. even though this is a distinction that is not commonly made or emphasized in philosophies of aesthetics, it is, nevertheless, one that cor- relates with distinct patterns of activation during the expe- rience of the two different kinds of beauty. functional connectivity given this dichotomy, we naturally expected that some of the areas that were active above would show a positive, state-dependent positive connectivity with mofc. it is known that activity in the mofc (and vmpfc) can be mod- ulated by signals from other brain regions [harvey et al., ]. the areas showing a greater functional connectivity with the mofc during the experience of sorrowful beauty were the sma, mcc, and dlpfc, regions related to the experience of sad (negative) emotional empathy and the interpretation of others’ intentions, especially under sad or painful situations [lieberman, for a review; fan et al., ; weissman et al., ]. one study using diffusion- weighted and functional mri showed a direct connection between the sma and ofc area [johansen-berg et al., ]. it is known that aesthetic judgments under the influence of monetary value and sponsorship to artworks lead to increased functional connectivity between the mofc and the dlpfc, activity in the former being influenced by that of the latter [harvey et al., ; kirk et al., ]. hare et al., [ , ] reported that the dlpfc modulated value sig- nals encoded in the vmpfc/mofc when subjects were given information about the health status of a food item and conducted self-controlling dietary choice. joyful beauty, in contrast, did not exhibit a functional con- nectivity with the regions relating to negative empathy, but showed a greater connectivity with anterior part of the rmpfc, a region thought to be involved in mentalizing other people’s psychological perspective [e.g., amodio and frith, for a review; skerry and saxe, ]. it is not clear whether different patterns of activity in the rmpfc correlate with the experience of positive and negative emotion in mentalizing but some studies suggest that it responds more to positive and aesthetically pleasing stimuli [kreplin and fairclough, ; vessel et al., ]. an enhanced func- tional connection between mofc/vmpfc, mpfc, and mtg during the judgment of facial attractiveness has been reported in a previous ppi study [smith et al., ]. it has been suggested that the mofc encodes the aes- thetic value on the basis of a common neural scale regard- less of its source [e.g., ishizu and zeki, ; pegors et al., ; zeki et al., ], leading to an enquiry on how rele- vant information, such as emotional context, modulates perceived aesthetic value and how such a modulation is represented in neural terms, besides activity within the mofc [pegors et al., ]. the findings from recent studies, some mentioned above, have suggested that the mofc inter- acts with other brain systems during evaluation of reward values in a ‘context-dependent’ manner [levy and glimcher, ; smith et al., ]. we have revealed that there is an increased functional connectivity between the mofc and anterior rmpfc in joyful beauty and between the mofc and the sma/mcc and the dlpfc in sorrowful beauty. this find- ing suggests that ( ) the brain engages two specialised sys- tems, a reward-related one (the mofc) and empathy-related regions; these are dissociable from each other depending upon whether the experience has a positive or negative emo- tional valance (the sma/mcc and rmpfc), and ( ) the empathy-related regions may modulate activity within the mofc through functional connectivity, to enable us to experi- ence the contradictory aesthetic and emotional values. in summary, therefore, functional connectivity between mofc and other cortical areas during the experience of beauty is dictated by whether the experienced beauty is joyful or sorrowful. it is interesting to discuss briefly the neural correlates of pleasure evoked by listening to sad music, which is also regarded as being a positive aesthetic experience with a neg- ative emotional valence [schubert, ]. such a contradic- tory experience can be seen in many forms of art, including paintings and films [e.g., hanich et al., ; leder et al., ] but is most notable and relatively well studied in music. among previous behavioral and neuroimaging stud- ies on sad music [e.g., kawakami et al., ; suzuki et al., ; taruffi and koelsch, ], a recent one [sachs et al., ] has argued that sad music is found pleasurable when ( ) it is perceived as non-life-threatening and with, no immediate real life implication; ( ) it is aesthetically pleas- ing; and ( ) it has certain psychological benefits, such as mood regulation caused by recollection of personal past events, which leads to activation within hippocampus/par- ahippocampal gyrus. we did not find hippocampal activity in the sorrowful beauty condition in the current study; r experience of sorrowful beauty r r r instead, we found activation within sma/mcc, indicating empathy and perspective taking toward other people. this may be due to a difference in the nature of visual and musi- cal perception. with visual stimuli, viewers can immediately empathize with sufferers or wounded people depicted in an image. by contrast, music, having no figurative representa- tion, may make listeners adopt a more ‘self-referential mode’ and recall personal-relevant memories. this points to possible interesting future studies, of how the brain reacts to the experience of sadness evoked by different sources. conclusion it is gratifying to us that an inspiration derived from a literary source should have led to work which has given us a little, but not much, more knowledge about the brain mechanisms that are engaged during aesthetic experiences. acknowledgment we thank yen yu for his helpful comments. this study was supported by the wellcome trust, london. conflict of interest the authors declare no conflict of interest. references acevedo bp, aron en, aron a, sangster md, collins n, brown ll ( ): the highly sensitive brain: an fmri study of sen- sory processing sensitivity and response to others’ emotions. brain behav : – . amodio dm, frith cd ( ): meeting of minds: the medial fron- tal cortex and social cognition. nat rev neurosci : – . baumann o, mattingley jb ( ): functional topography of pri- mary emotion processing in the human cerebellum. neuro- image : – . bohrn ic, altmann u, lubrich o, menninghaus w, jacobs am ( ): when we like what we know–a parametric fmri analy- sis of beauty and familiarity. brain lang : – . calvo-merino b, jola c, glaser de, haggard p ( ): towards a sensorimotor aesthetics of performing art. conscious cogn : – . cross es, kirsch l, ticini lf, schutz-bosbach s ( ): the impact of aesthetic evaluation and physical ability on dance percep- tion. front hum neurosci : . cunningham wa, raye cl, johnson mk ( ): implicit and explicit evaluation: fmri correlates of valence, emotional inten- sity, and control in the processing of attitudes. j cogn neuro- sci : – . eisenberger ni, lieberman md ( ): why rejection hurts: a common neural alarm system for physical and social pain. trends cogn sci : – . etkin a, egner t, kalisch r ( ): emotional processing in ante- rior cingulate and medial prefrontal cortex. trends cogn sci : – . fan y, duncan nw, de greck m, northoff g ( ): is there a core neural network in empathy? an fmri based quantitative meta-analysis. neurosci biobehav rev : – . farrow tf, zheng y, wilkinson id, spence sa, deakin jf, tarrier n, griffiths pd, woodruff pw ( ): investigating the func- tional anatomy of empathy and forgiveness. neuroreport : – . fletcher pc, happe f, frith u, baker sc, dolan rj, frackowiak rs, et al. 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Úvod krása je fenomén tak starý jako lidská společnost. antropologové a archeologové nachází důkazy o tom, že zdobení a zkrášlování patřilo ke všem kulturám, bez ohledu na jejich vyspělost. podle nancy etcoffové [ ] starověký egypt znal „make-up“. egyptská královna nefertiti se stala symbolem ženské moci i krásy. v antice byla krása považována za „šestý smysl“. platón, autor často citovaného výroku „krása je v očích pozorovatele“, považoval ideál krásy za jeden z nejdů- ležitějších ideálů, jedinečný tím, že je postižitelný smysly, přičemž krása těla je pouze jednou z forem krásy (nejvýše stojí absolutní krásno). sapfó svým výro- kem „co je hezké, to je dobré“, obrazně řečeno, vyjádřila podstatu teorie genera- lizace statusu, zatímco aristotelův výrok „krása je nejlepší doporučující dopis“, není daleko od zjištění soudobých studií o roli krásy na trhu práce. darwin [ ] viděl ve fyzické atraktivitě a sexuální přitažlivosti klíč k pochopení procesů za- jišťujících posilování geneticky založené odolnosti druhů. v podobném duchu evoluční biologové považují krásu za „certifi kát“ fenotypické i genotypické ge- netické kvality [grammer et al. ]. fyzické atraktivitě a kráse je věnována čím dál větší pozornost i v ekono- mii, sociologii a psychologii, a to zejména od poslední dekády minulého století. zásluhu má na tom (nejenom) naomi wolfová, která se v monografi i the beauty myth (mýtus krásy) [wolf ] pokusila prokázat, že krása není nic jiného než ideologický konstrukt sloužící jako nový nástroj patriarchálního útlaku žen [ibid.: ]. Částečně v reakci na wolfovou začali ekonomové [hamermesh ], psy- chologové [etcoff ; langlois et al. ], literární vědci [gottschall et al. ] a sociologové [hakim , ] – zpravidla s odvoláním na antropologické vý- zkumy [buss ; buss et al. ; buss, shackelford ], výzkumy z oblasti evoluční biologie [ridley ] a experimentální psychologie [dion, brescheid, walster ; byrne, london, reeves ; clifford, walster ] – přinášet dů- kazy o tom, že krása a fyzická atraktivita jsou biologicky ukotvené fenomény, s nimiž není možné se vypořádat jednoduše tím, že je vykážeme do říše mýtů. cílem této stati ovšem není vstupovat do sporu o povaze krásy, tj. zda jde o sociální konstrukt nebo biologicky ukotvený fenomén, ale prokázat, že fyzic- ká atraktivita je specifi ckou formou kapitálu, která je svými efekty srovnatelná s lidským kapitálem, resp. s ostatními formami kapitálu, s nimiž ekonomie a so- ciologie operují již více než půl století. z tohoto hlediska není podstatné, na které straně zmíněného diskurzu stojíme, ale to, zda krása má na trhu práce vliv srov- natelný s jinými „kapitály“, resp. formami kapitálu. podobně argumentuje například i deborah rhode [ ], podle níž krása sice má biolo- gické kořeny, nicméně její hypertrofi zace jak na trhu práce (skrytá i otevřená diskriminace méně atraktivních), tak ve spotřebě a v životním stylu („zkrášlovací“ průmysl, marketing) činí z krásy účinný nástroj diskriminace a zdroj nových forem nespravedlnosti. podle wolfové dokonce ani neexistuje žádný důkaz, že by před rokem ženám na kráse nějak zvlášť záleželo [wolf : ]. †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce v úvodní části se stručně věnujeme teoretické konceptualizaci fyzické atrak- tivity v ekonomii a sociologii. dále načrtneme hlavní hypotézy týkající se role fyzické atraktivity na trhu práce. platnost hypotéz budeme testovat na datech z unikátního českého výzkumu, v němž byla fyzická atraktivita zjišťována třemi metodami (sebehodnocením respondenta, hodnocením respondenta tazatelem, hodnocením fotografi í respondentů expertní skupinou), a to v kontextu dalších proměnných používaných v analýzách faktorů působících na úspěch na trhu prá- ce. důležité jsou přitom dvě proměnné, o nichž je známo, že v úspěchu na trhu práce hrají klíčovou roli, jmenovitě dosažené vzdělání a kompetence. sledujeme přitom tři cíle: (a) aplikací metody strukturního modelování pro kázat, že v České republice hraje fyzická atraktivita v úspěchu na trhu prá- ce významnou roli, a to i při kontrole sociálního původu, vzdělání a inteligence (resp. měřených kompetencí) a dalších relevantních proměnných; (b) prokázat, že v hlavních kauzálních vazbách, v nichž fi guruje fyzická atraktivita, existují významné rozdíly mezi muži a ženami; (c) zjistit, zda rozdíly v efektech fyzické atraktivity na úspěch na trhu práce mezi muži a ženami mají stejnou nebo opač- nou „polaritu“ než v jiných zemích, a přispět tak do diskuse o jejich kulturní a so- ciální podmíněnosti a tím i k postupnému budování teorie, která by tyto rozdíly uspokojivě vysvětlila. za hlavní přínos stati považujeme testování vlivu subjektivně měřené fyzic- ké atraktivity na úspěch na trhu práce (tj. na sociálně-ekonomický status zaměst- nání a příjem) při kontrole robustně měřených kognitivních schopností (kompe- tencí) a dalších relevantních proměnných (sociálně-ekonomický původ, dosažené vzdělání), a to na reprezentativním souboru svou velikostí umožňujícím aplikaci strukturního modelování na podsouborech defi novaných pohlavím a věkem. právě využití strukturního modelování umožnilo do systému příčinných vazeb zahrnout řadu kontrolních proměnných, které v analýzách vlivu fyzické atrak- tivity na úspěch na trhu práce často chybí nebo jsou měřeny méně robustními protokoly měření (kompetence v metrice oecd piaac, vícedimenzionálně mě- řený sociálně-ekonomický a kulturní status výchozí rodiny, sociálně-ekonomický Šlo o první následné šetření provedené na souboru respondentů z národního výzkumu kompetencí dospělých realizovaného v rámci projektu oecd piaac. pokud je nám zná- mo, podobný výzkum zahrnující komplexní (vícedimenzionální) měření fyzické atrakti- vity i kompetencí (inteligence) a provedený na rozsáhlém reprezentativním souboru (přes dva tisíce respondentů) nebyl zatím uskutečněn v žádné jiné zemi. jak ukážeme dále, vliv krásy na příjem byl sice prokázán i v jiných zemích, ale jak mě- ření krásy, tak měření klíčových kontrolních proměnných (zejména měřené kompetence, sociálně-ekonomický původ a sociálně-ekonomický status zaměstnání) bylo méně robust- ní než v českém výzkumu. dosavadní studie rozdíly v efektech krásy na příjem mezi muži a ženami spíše jen kon- statovaly, aniž se pokusily o hlubší teoretické vysvětlení. výjimkou jsou práce hakimové [ , ], které však, zejména pokud jde o měření krásy, nestojí na robustním empiric- kém základu. sociologický časopis / czech sociological review, , vol. , no. status zaměstnání). tento přístup v důsledku použití latentních proměnných vý- razně posiluje roli společných variancí a snižuje tak podíl „šumu“ v testovaných kauzálních vazbách. krása jako kapitál v ekonomické perspektivě s cílem objasnit pravidelnosti v ekonomické a sociální reprodukci a identifi kovat hlavní zdroje ekonomických a sociálních nerovností jsou v ekonomii od poloviny minulého století rozvíjeny a ověřovány teorie různých kapitálů, od ekonomické- ho kapitálu, jehož základní charakteristiky popsal karel marx [( ) , ( ) ], přes kapitál fi nanční, přírodní, sociální až po lidský kapitál, jehož teorii v návaznosti na johna stuarta milla [( ) ] rozvíjeli zejména ekonomič- tí „nobelisté“ gary becker [ ] a theodor schultz [ , ]. vše nasvědču- je tomu, že ekonomie je jak teoreticky, tak empiricky otevřená zahrnutí fyzické atraktivity (krásy) do širší defi nice lidského kapitálu. ostatně předchůdci mo- derní teorie lidského kapitálu adam smith [smith, garnier ] a john stuart mill [( ) ] pod lidský kapitál zahrnovali prakticky vše, čím člověk na trhu práce může konkurovat ostatním. každodenní zkušenosti i empirické studie sku- tečně vedou k závěru, že atraktivnější lidé jsou ve srovnání s méně atraktivními úspěšnější v hledání zaměstnání [shahani-denning ; musumeci, shahani- -denning ; podratz, dipboye ], častěji obsazují vyšší pozice a mají zpra- vidla i vyšší příjmy [hamermesh, biddle ]. vliv atraktivity přitom zůstává statisticky významný i po kontrole vlivů vzdělání, věku a dalších relevantních proměnných. to vše svědčí ve prospěch teze, že fyzickou atraktivitu lze považo- vat za jednu z komponent lidského kapitálu. empirická evidence však nestačí. je třeba identifi kovat mechanismy, jimiž na trhu práce atraktivita působí. hamermesh a biddle [ ] nabízí tři základní teoretické modely vysvětlu- jící větší šance atraktivních jedinců na ekonomický úspěch. první z nich, nazý- vaný „model produktivity“, spočívá v předpokladu, že v některých zaměstná- ních atraktivnější jedinci dosahují lepších výsledků proto, že jejich práce spočívá v kontaktu s lidmi, kteří – jak prokázaly psychologické experimenty a jak ostatně můžeme potvrdit i na základě vlastní zkušenosti – přijmou službu nebo koupí zboží nabízené fyzicky atraktivnějším jedincem. u těchto zaměstnání (právníci, služby, agenti fi nančních institucí atd.) lze očekávat, že zaměstnavatel bude při výběru uchazečů o práci upřednostňovat jedince s vyšší atraktivitou před prů- měrně a podprůměrně atraktivními, nehledě na to, že atraktivnější jedinci často mají větší sklon právě k povoláním či zaměstnáním tohoto typu. tento model preferencí (diskriminace) na základě atraktivity je založen na mechanismu ozna- čovaném jako „diskriminace klientem“ (customer discrimination). kromě toho se rozlišují ještě dva další mechanismy zvýhodňující nadprů- měrně atraktivní jedince proti méně atraktivním, souhrnně označované jako dis- kriminace zaměstnavatelem. první z nich vychází z beckerovy ekonomie diskri- minace [becker ], jejíž jedna větev, konkrétně diskriminace založená na vkusu †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce („taste based discrimination“), predikuje menší ochotu zaměstnavatele dát vyšší mzdu méně atraktivnímu jedinci, může-li více odměnit nadprůměrně atraktiv- ního zaměstnance. jde tedy o přímou příjmovou diskriminaci méně atraktivních jedinců. podobně funguje diskriminace v ochotě přijmout do zaměstnání nebo na vyšší pozici podprůměrně atraktivního jedince, je-li k dispozici atraktivněj- ší jedinec, aniž by tento výběr byl nutně spjat s očekáváním vyšší produktivity u atraktivnějšího jedince v důsledku příznivějších reakcí zákazníků či klientů, jako je tomu v případě „modelu produktivity“. tento třetí model, v literatuře nazývaný „occupational-crowding“, původně navržený na vysvětlení segregace povolání na typicky „ženská“ a „mužská“ [bergman ], je založen na před- pokladu, že atraktivní lidé dostávají přednost před méně atraktivními, aniž se nutně očekává, že atraktivita má na dané pozici přímý vliv na produktivitu [ha- mermesh, biddle : ]. ve výzkumné praxi není snadné působení těchto tří modelů diskriminace empiricky oddělit a poměrně přesně určit, který z nich stojí za konkrétním efek- tem krásy či atraktivity na úspěch na trhu práce. lze však očekávat, že všechny tři mechanismy jednotlivě i ve vzájemných souvislostech vedou k tomu, že atrakti- vita působí na trhu práce jako specifi cká dimenze lidského kapitálu, kterou nelze vysvětlit jeho nejčastěji používanými indikátory, tj. vzděláním a kompetencemi. v tomto smyslu s fyzickou atraktivitou jako komponentou lidského kapitálu pra- cují převážně ekonomové, a to jak v analýzách „ekonomické návratnosti“ krásy [hamermesh, biddle ], tak ve studiích návratnosti investic do krásy [hamer- mesh ; hamermesh, meng, zhang ]. poněkud odlišné vysvětlení efektů krásy na úspěch na trhu práce nedáv- no předložili a testovali mobius a rosenblat [ ], kteří též rozlišují tři mecha- nismy, které sice nejsou přímo odvozené od teorie lidského kapitálu, ale „kapa- cita“ uspět v konkurenci s ostatními je v nich přítomná. první spočívá v tom, že fyzicky atraktivní jedinci vyvolávají u nadřízených vyšší důvěru, přičemž vyšší důvěra vede k vyšší mzdě. dále, při stejné důvěře jsou fyzicky atraktivnější za- městnanci (nesprávně) považováni za kompetentnější, což též příznivě působí na mzdu. a konečně, opět při stejné důvěře, fyzicky atraktivnější jedinci mají lepší verbální, komunikační a sociální dovednosti, což je též oceňováno vyšší mzdou. zde je ovšem třeba poznamenat, že k těmto výsledkům a závěrům autoři dospěli na základě experimentu provedeného na skupinách studentů rozdělených na za- městnance a zaměstnavatele, což i samotné autory vedlo k opatrnosti, pokud jde o zobecnění závěrů. pro tyto teoretické předpoklady nacházíme oporu v již provedených analý- zách, zejména pak ve studiích, které na sklonku minulého století provedli hamer- zde je třeba poznamenat, že becker měl v případě „taste based discrimination“ na mysli zejména rasovou diskriminaci. diskriminace je zde chápána jako specifi cké zacházení, tj. jak v negativním, tak v pozi- tivním smyslu. sociologický časopis / czech sociological review, , vol. , no. mesh a biddle [hamermesh, biddle ; biddle, hamermesh ; hamermesh ], averett a korenman [ ], scholz a sicinski [ ] a další. jedna z prvních studií, které se vlivem krásy na úspěch na trhu práce zabývaly [hamermesh, bi- ddle ], prokázala, že fyzická krása se na trhu práce vyplácí, zejména pokud jde o příjmy. stručně řečeno, nadprůměrně atraktivní jedinci v usa a kanadě si vydělají o až % více než podprůměrně atraktivní, což je efekt srovnatelný s vlivem pohlaví a rasy. věc ovšem není tak jednoduchá, protože za tímto obec- ným závěrem se skrývají poměrně velké rozdíly mezi zeměmi i mezi muži a že- nami. pokud jde o muže, v usa byl pozitivní efekt nadprůměrné atraktivity na příjem menší než negativní efekt podprůměrné atraktivity. v kanadě tomu bylo u mužů naopak, tj. pozitivní efekt nadprůměrné atraktivity na příjem byl u mužů větší než negativní efekt podprůměrné atraktivity. podobně tomu bylo u žen. za- jímavé ale je, že negativní efekty podprůměrné atraktivity na příjem byly větší u mužů, zatímco pozitivní efekty nadprůměrné atraktivity byly zjištěny u žen. analýzy provedené na spojených souborech za usa a kanadu, které ved- ly k robustnějším výsledkům, pak ukázaly, že při kontrole většiny relevantních proměnných (zejména pak vzdělání a věku) jsou muži více penalizováni za pod- průměrnou atraktivitu (o % nižší příjem ve srovnání s průměrně atraktivními) než zvýhodňováni nadprůměrnou atraktivitou (o % vyšší příjem ve srovnání s průměrně atraktivními). příjmový rozdíl mezi nadprůměrně a podprůměr- ně atraktivními muži tak činil okolo %. u žen byly rozdíly mnohem menší: podprůměrně atraktivní ženy si ve srovnání s průměrnými vydělaly o zhruba % méně, nadprůměrně atraktivní ženy si ve srovnání s průměrnými vydělaly o zhruba % více, což představuje příjmový rozdíl mezi nadprůměrně a pod- průměrně atraktivními ženami okolo % příjmového průměru [hamermesh, biddle ]. studie současně ukázala, že povolání s vysokým podílem interpersonál- ní komunikace skutečně „přitahují“ nadprůměrně atraktivní jedince, resp. trh práce jedince s vysokou atraktivitou do těchto povolání směruje [hamermesh, biddle : ]. v této souvislosti je také zajímavá studie, která ukazuje, že studenti práva, kteří byli během studií považováni za nadprůměrně atraktivní, měli po pěti letech po ukončení studií vyšší příjem než méně atraktivní [biddle, hamermesh ]. ve stejném duchu hamermesh a parkerová [ ] prokázali, že v hodnocení výkonu vyučujících ze strany studentů se mimo jiné uplatňuje i to, jak jsou vyučující atraktivní. role krásy v životním úspěchu v sociologické perspektivě sociologicky relevantní odpověď na otázku, zda je krása kapitál, lze najít v teo rii různých forem kapitálu pierra bourdieua [ ]. na otázku, co je kapitál, bour- dieu odpovídá, že v principu jde o jakoukoli „kapacitu“ umožňující získat ur- čitou výhodu a přímo i nepřímo generovat zisk v ekonomickém smyslu. tuto †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce vlastnost má podle bourdieua nejen ekonomický kapitál, ale též kulturní kapitál, který – zejména díky osvojení si bohatšího jazyka – usnadňuje získat vyšší vzdě- lání, lepší zaměstnání a pohybovat se ve „vyšší společnosti“, což opět přímo i ne- přímo (zejména díky sociálnímu kapitálu) zvyšuje šance na ekonomický úspěch. podobně pak funguje i sociální kapitál, který spočívá v sociálních sítích fungují- cích na principu vzájemně výhodných reciprocit a směn mezi jedinci aktivně par- ticipujícími na takových sítích, které usnadňují přístup k důležitým informacím, zdrojům i žádoucím pozicím. podstatou fungování všech forem kapitálu je podle pierra bourdieua nutnost akumulace a reprodukovatelnost (do každého kapitálu je třeba investovat a neustále jej udržovat na určité úrovni) a konvertibilita (jed- notlivé formy kapitálu jsou navzájem převoditelné). ačkoli ekonomický kapitál je v základu všech dalších forem kapitálu, nelze ani jednu z nich na ekonomic- ký kapitál redukovat. na druhé straně všechny „neekonomické“ formy kapitálu efektivně fungují mimo jiné i proto, že ekonomický kapitál je jejich společným jmenovatelem. neméně významnou teoretickou perspektivou umožňující vysvětlit roli fy- zické atraktivity v životním úspěchu je teorie statusové generalizace [webster, driskell ; webster, foschi ] a její přímá aplikace na roli fyzické atrak- tivity [webster, driskell ]. badatelé zabývající se tímto fenoménem hovoří o generalizaci statusu v situacích, kdy se na základě vnějších (pozorovatelných) statusových charakteristik (pohlaví, rasa, fyzická atraktivita apod.) vytváří úsu- dek o těch vlastnostech, které nejsou na první pohled zřejmé a vyžadují bližší seznámení a zkoumání (inteligence, kompetence, výkonnost, spolehlivost, status zaměstnání, příjem atd.). tato teorie mezi vnější statusové charakteristiky expli- citně zahrnuje i fyzickou krásu, z níž pozorovatelé usuzují, stejně jako z jiných charakteristik (pohlaví, rasa atd.), na jiné důležité statusové charakteristiky. jak teorie [webster, driskell ; berger, zelditch ], tak provedené experimen- ty [clifford, walster ; dion et al. ; kirkpatrick, cotton ; elder ] prokazují, že fyzicky atraktivnější jedinci jsou vnímáni jako intelektuálně zdat- nější, kompetentnější a celkově úspěšnější [viz též jackson, hunter, hodge ]. v důsledku těchto větších očekávání jsou pak nositelé těchto vlastností nakonec také úspěšnější. v neposlední řadě je třeba uvést teoretickou inspiraci z dílny catherine ha- kimové, jmenovitě pak v její teorii „erotického kapitálu“. ačkoli erotický kapitál není totožný s pouhou krásou, protože kromě fyzické přitažlivosti v sobě zahrnu- je zvláštní sociální energii, schopnost lehce a příjemně komunikovat, šarm, hra- vost a erotickou imaginaci, fyzická přitažlivost (krása) je jeho nutnou podmínkou [hakim , ]. podstatné je, že hakimová přímo navazuje na pierra bour- dieua a erotický kapitál označuje za čtvrtou formu kapitálu (ekonomický, kultur- jde svým způsobem o mechanismus sebenaplňujícího se proroctví, dříve popsaný w. i. tho masem [thomas, thomas ] a r. k. mertonem [ ]. sociologický časopis / czech sociological review, , vol. , no. ní, sociální, erotický). ačkoli nemusíme s hakimovou souhlasit ve všech bodech její teorie erotického kapitálu, nelze popřít, že ve stále více „sexualizované kultu- ře“ moderních západních společností hraje erotický kapitál velkou roli, a to nejen při hledání partnera, ale – podobně jako krása sama o sobě – i na trhu práce. v tomto kontextu je třeba zmínit, že v novějších studiích se začíná rozlišo- vat mezi fyzickou atraktivitou jako takovou a upraveností (grooming), která je výsledkem péče o vzhled. například wong a penner [ ] jako mnozí jiní analy- zovali vliv fyzické atraktivity na příjem, ale kromě hodnocení celkové atraktivity ještě hodnotili momentální upravenost respondenta a dospěli k závěru, že ačkoli vliv fyzické atraktivity jako takové je prokazatelný (velmi atraktivní lidé mají ve srovnání s průměrně atraktivními příjem o % vyšší), vliv upravenosti se uká- zal být větší (vložením vnímané upravenosti respondenta do rovnice vysvětlující příjem příspěvek k příjmu vyplývající z nadprůměrné atraktivity klesl z % na %, zatímco čistý vliv nadprůměrné upravenosti byl %). současně se ukáza- lo, že kultivovaná krása má u žen větší vliv než krása „od přírody“ a že malus za neupravenost je větší než malus za podprůměrnou atraktivitu. bez ohledu na to, zda budeme spolu s ekonomy fyzickou atraktivitu po- važovat za komponentu šířeji chápaného lidského kapitálu nebo – v souladu s teorií statusové generalizace – za zdroj generalizací, či – spolu s bourdieuem a hakimovou – za jednu z forem kapitálu, můžeme se opřít o předpoklad, že jde o „kapacitu“, která se, podobně jako inteligence, vzdělání a další osobností rysy, zhodnocuje jak na trhu práce, tak v životních šancích obecně. důležitou otázkou, na kterou je třeba hledat odpověď, jsou rozdíly v roli fyzické atraktivity na trhu práce mezi muži a ženami. zahraničí studie, založené převážně na datech z usa a kanady [hamermesh, biddle ], ukazují, že ženy zhodnocují fyzickou atraktivitu v příjmech méně než muži, což – jak pozname- návají jejich autoři – je v rozporu s předpoklady, na nichž stojí kritika role krásy [wolf ]. rozbor několika možných vysvětlení (jde o metodologický artefakt vyplývající z měření atraktivity, selektivní participace atraktivnějších žen na trhu práce, větší šance velmi atraktivních žen na ekonomicky „výhodný“ sňatek) uká- zal, že tyto faktory s největší pravděpodobností nejsou ve hře [hamermesh, bid- dle : – ]. zatím nezbývá než připustit, že jde o určitý kulturní vzorec, který však nemusí být univerzálně platný. současně lze předpokládat, že analýzy provedené na více než třicet let sta- rých datech nemohly zachytit efekty pokračující emancipace žen, resp. zvyšování jejich zastoupení v povoláních, v nichž původně jednoznačně dominovali muži, aniž bychom se zde mohli rolí erotického kapitálu zabývat hlouběji, za zmínku stojí jed- na z hlavních tezí hakimové [ ], podle níž erotickým kapitálem disponují muži stejnou měrou jako ženy, přičemž obě pohlaví by neměla váhat s tímto kapitálem vědomě pracovat doma, ve společnosti, na trhu práce i na pracovišti. nelze se divit, že tyto názory nechávají v klidu jen málokoho, popřít samotnou existenci erotického kapitálu však zřejmě nebude snadné. †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce což je mimo jiné dáno i expanzí podílu žen s vysokoškolským vzděláním. větší zastoupení žen v těchto povoláních s vyššími příjmy může vést nejen k větší kon- kurenci mezi muži a ženami, ale též mezi ženami navzájem, v níž vysoce atrak- tivní ženy mohou být ve srovnání s méně atraktivními ženami příjmově úspěšněj- ší, zřejmě i proto, že disponují větším sebevědomím (náš výzkum také prokázal statisticky významnou souvislost mezi sebevědomím a fyzickou atraktivitou). v tomto smyslu nepovažujeme výsledky předchozích studií provedených v usa a v kanadě za přenositelné do současnosti, zejména pak na Českou republiku, kde změny vyvolané transformací, modernizací a individualizací preferencí mezi orientací na domácnost a na kariéru [hakim ; weidnerová, matějů ] zřej- mě působí i na strategie žen prosadit se na trhu práce s využitím kapitálů, jejichž role byla v minulosti méně významná, resp. byla překryta různými stereotypy. k těmto kapitálům jistě patří i fyzická atraktivita a erotický kapitál. dosavadní studie tak rozdíly v efektech krásy na příjem mezi muži a že- nami spíše jen konstatovaly, aniž se pokusily o hlubší teoretické vysvětlení. vý- jimkou jsou práce hakimové věnující se „erotickému kapitálu“ [hakim , ], operující s tezí, že tento specifi cký kapitál zhodnocují více ženy než muži, pravděpodobně proto, že sexuální defi cit mužů je trvale větší než sexuální defi - cit žen [hakim ], takže fyzická krása žen vyvolává u mužů častěji pozitivní odezvu než fyzická krása mužů u žen. tyto práce však, zejména pokud jde o mě- ření krásy a dalších kontrolních proměnných, nestojí na robustním empirickém fundamentu. hypotézy a analytický plán jak teorie, tak dosavadní empirické výsledky ukazující na nezanedbatelnou roli fyzické atraktivity v úspěchu na trhu práce nás vedou k formulování následují- cích tří hypotéz: . v souladu s převážně ekonomickými teoriemi (teorie diskriminace, teorie dis- kriminace klientem) a sociologickou teorií různých forem kapitálu očekává- me, že významnou roli v získání zaměstnání s vyšším sociálně-ekonomickým statusem a dosažení vyššího příjmu hraje fyzická atraktivita jedince, a to při kontrole dosaženého vzdělání, kompetencí a sociálně-ekonomického původu. . kauzální vazby, jimiž se sociální původ, vzdělání, kompetence, sociálně-eko- nomický status zaměstnání a atraktivita transformují v příjem, nejsou u mužů a žen stejné. . v souladu s pokračující emancipací žen a jejich pronikáním do skupin povolá- ní s vyššími příjmy (což zvětšuje konkurenci mezi ženami navzájem), a prav- děpodobně silnějším efektem „erotického kapitálu“ na straně žen (v důsledku trvale většího sexuálního defi citu na straně mužů), očekáváme větší zhodno- cení fyzické atraktivity na trhu práce u žen než u mužů. sociologický časopis / czech sociological review, , vol. , no. uvedené hypotézy testujeme primárně pomocí strukturního modelování, které – na rozdíl od běžné regresní analýzy – umožňuje odhadovat koefi cienty pro celá vztahová zřetězení, v nichž sledované charakteristiky mohou fi gurovat součas- ně na straně závisle i nezávisle proměnných. strukturní model navíc umožňuje identifi kovat nejen přímé efekty (bezprostřední kauzální vztah dvou proměn- ných), ale též efekty nepřímé (působení jedné proměnné na druhou prostřednic- tvím jiných proměnných). výhodou strukturního modelování je i to, že umož- ňuje pracovat nejen s manifestními (přímo měřenými) proměnnými (v tom se příliš neliší od regresní analýzy), ale též s latentními proměnnými, které jsou defi novány přímo v modelu podobně jako ve faktorové analýze [blíže viz matějů ; anýžová ]. na tomto místě je ovšem třeba poznamenat, že pokusy o kauzální výklad společenských jevů na základě statických dat jsou vždy poněkud problematické, protože předpokládané příčiny a následky nelze bez longitudinálních dat jed- noznačně umístit na časové ose. zatímco u některých vlastností či proměnných víme, zda jde o příčinu nebo následek (například vzdělání otce a matky je jed- ním z faktorů ovlivňujících vzdělání respondenta, těžko tomu může být naopak), v jiných případech to už tak jednoznačné není. například dosažené vzdělání lze pokládat za jednu z příčin naměřených kompetencí, současně však platí, že šance dostat se na určitý stupeň vzdělání jsou již zpravidla podmíněny prokázanými schopnostmi. oprávněná skepse týkající se možnosti kauzálního výkladu spole- čenských jevů by nás ale neměla vést k rezignaci na pokusy jdoucí tímto směrem. je pouze třeba uvažovat o míře platnosti hlavních předpokladů, totiž že zkou- mané charakteristiky spolu opravdu souvisí a že uvažované příčiny skutečně – či alespoň s vysokou mírou pravděpodobnosti – předcházely následkům. testovaný strukturní model je uveden v diagramu . jeho základní teoretic- ké předpoklady lze shrnout následovně: – vzdělání, kompetence, zaměstnanecký status, příjem i samotná atraktivita jsou ve větší či menší míře ovlivněny sociálním původem. – dosažené vzdělání působí přímo na kompetence, zaměstnanecký status a pří- jem. vzdělání působí na příjem i nepřímo, tj. prostřednictvím zaměstnanecké- ho statusu. – kompetence působí na zaměstnanecký status a příjmy, v případě příjmů navíc model opět rozlišuje mezi přímým a nepřímým vlivem kompetencí (šance na lepší místo a vyšší plat na stejné pozici). – fyzicky atraktivnější jedinci mají vyšší šanci získat zaměstnání s vyšším so ciál- ně-ekonomickým statusem a dosáhnout vyššího příjmu. samotný kauzální model vysvětlující formování kompetencí a jeho teoretické zdůvod- nění, včetně vysvětlení role jednotlivých proměnných v kauzálních vazbách, byl již po- psán a testován v matějů, večerník [ ]. teoretické předpoklady a výsledky analýzy po- dobného kauzálního modelu s klíčovými proměnnými, jako je sociálně-ekonomický status zaměstnání a příjem (avšak bez fyzické atraktivity), v matějů, anýžová [ ]. †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce – vztahy mezi atraktivitou na jedné straně a kompetencemi a vzděláním na stra- ně druhé ponecháváme neorientované, tj. v poloze korelací, a nikoli kauzál- ních efektů. předpokládáme, že atraktivita na jedné straně ovlivňuje dosaže- né vzdělání, na druhé straně lidé s vyšším vzděláním si více uvědomují roli atraktivity v životním úspěchu a více se tedy na svůj vzhled a vystupování zaměřují, což nepochybně přispívá k výslednému efektu. s odkazem na jiné studie [viz například clifford, walster ; judge, hurst simon ] součas- ně předpokládáme působení tzv. pygmalion efektu [rosenthal, jacobson ], podle nějž mají atraktivnější jedinci větší šanci na dosažení vyššího vzdělání, a to zejména díky tomu, že hezčí děti upoutávají pozitivní pozornost učitelů, což vede k lepším známkám, vyšším aspiracím atd. podobně je tomu v přípa- dě vztahu mezi atraktivitou a inteligencí (kompetencemi) [kanazawa, kovar ]. současně ale inteligence může, podobně jako vzdělání, přispívat k „pěs- tování“ atraktivity jako ekonomicky zhodnotitelného kapitálu. diagram . schéma příčinných vazeb determinace výdělku poznámka: fed (vzdělání otce), med (vzdělání matky), books (počet knih v domác- nosti rodičů), famses (latentní proměnná – sociálně-kulturní status výchozí rodiny), interviewer (hodnocení tazatelem), self-eval (sebehodnocení), bmi (body mass index), beauty (latentní proměnná – fyzická atraktivita), edyrs (počet let strávených formálním vzděláváním), isei (sociálně-ekonomický status zaměstnání), inc (příjem), zlit (standardizovaný index čtenářské gramotnosti), znum (standardizovaný index numerické gramotnosti), comp (latentní proměnná – kompetence). famses beauty edyrs isei inc comp fed med interviewer self-eval bmi zlit znum books sociologický časopis / czech sociological review, , vol. , no. model bude aplikován na tři věkové skupiny (do let, až let, nad let) a pro muže a ženy zvlášť. hlavním důvodem pro aplikaci modelu separátně na populaci mužů a žen je možnost identifi kovat předpokládané genderové rozdíly v kauzálních vazbách mezi klíčovými proměnnými (hypotézy a ). Účelem tedy není jen identifi kace, popř. kontrola vlivu pohlaví na klíčové proměnné, ale přímé porovnání síly efektů (např. vliv atraktivity na příjem) mezi muži a ženami, což umožní případně odhalit možné kulturní rozdíly mezi americkou a evropskou společností. rozdělení populace na tři věkové skupiny je založeno na předpokla- du, že vliv fyzické atraktivity na úspěch na trhu práce je nejsilnější ve středním, ekonomicky produktivním věku, kdy se jedinci blíží vrcholu profesionálních ka- riér. detailní výsledky pro mladší a starší věkovou skupinu používáme praktic- ky jen pro ilustraci rozdílů mezi věkovými skupinami. důvodem jsou i relativně malé počty ekonomicky aktivních jedinců v nejmladší a nejstarší věkové skupině. v prvním kroku představíme základní fakta o působení atraktivity na trhu práce, aniž bychom blíže zkoumali další souvislosti, v jejichž kontextu atraktivita působí (zejména vzdělání, kompetence a věk). dále aplikací strukturního mode- lování působení atraktivity na trhu práce zasadíme do širšího kontextu dalších proměnných. v dalším kroku budeme v zájmu srovnatelnosti s výsledky analýz provedených v zahraničí aplikovat i metodu lineární regrese, která umožňuje sta- novit tzv. čisté efekty nadprůměrné a podprůměrné krásy na sociálně-ekonomic- ký status zaměstnání a příjem. data, proměnné a metody data, s nimiž v této stati pracujeme, pochází z výzkumu, který navázal na roz- sáhlé šetření kompetencí dospělých „předpoklady úspěchu v práci a v životě“, uskutečněné v rámci projektu oecd-piaac. z výchozího šetření provedeného v letech až byly k dispozici údaje za respondentů ve věku až let. pro navazující výzkum bylo z tohoto základního souboru náhodně vy- bráno respondentů, na nichž bylo v roce provedeno navazující šetření zacílené zejména na fyzickou atraktivitu, osobnostní charakteristiky, hodnoty, so- ciální kapitál a některé dimenze životního způsobu. základní informace o šetření piaac provedeném v Čr lze nalézt v souhrnné zprávě z výzkumu [straková, veselý ]. sběr dat navazujícího šetření se uskutečnil metodou osobních rozhovorů a probíhal od podzimu do jara . do výzkumu se zapojilo respondentů, data sbíralo ta- zatelů. kontrolními mechanismy byly vedle konzistence dat nahrávky vybraných částí všech rozhovorů a telefonické kontroly náhodně vytipovaných respondentů. data byla převážena na populaci Čr podle aktuálních dat ČsÚ (zejména veřejné údaje z vŠps ) s využitím rim vážení (random iterative method) v spss podle pohlaví, věku, vzdělání a nuts . †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce navazující šetření sice umožňuje replikovat analýzy provedené v zahraničí, což v zájmu srovnatelnosti činíme, avšak rozsáhlejší okruh informací o respon- dentech, které výzkum díky svojí vazbě na projekt piaac poskytl, umožnil krásu a atraktivitu zkoumat v širším kontextu. základní a do značné míry unikátní výhodou propojení dat z navazujícího šetření s daty ze základního šetření je mož- nost pracovat s nebývale rozsáhlou množinou proměnných pokrývajících sociál- ní původ (vzdělání a zaměstnání rodičů), podrobné údaje o dosaženém vzdělání a zaměstnání, příjmy, údaje o rodině a zejména výsledky velmi důkladného mě- ření kompetencí. projekt piaac se zaměřil na následující tři domény kompetencí: (a) numerická gramotnost (num), (b) čtenářská gramotnost (lit) a (c) dovednost řešit problémy v prostředí informačních technologií (psl). v analýzách založených na strukturním modelování vytváříme latentní proměnnou comp (schopnosti, kompetence), založenou pouze na dvou dimen- zích, jmenovitě na numerické gramotnosti (num) a čtenářské gramotnosti (lit), odpovídající tzv. prvním plausibilním hodnotám, které souhrnně nazýváme kompetence či inteligence. dovednost řešit problémy v prostředí informačních technologií nepoužíváme, neboť její hodnoty jsou pouze pro ekonomicky aktiv- ní a pro respondenty, kteří prokázali alespoň elementární schopnost pracovat s počítačem. v deskriptivních a regresních analýzách používáme index schop- ností (abil), který vznikl zprůměrováním hodnot proměnných num a lit [(num+lit)/ ]. v textu často tuto proměnnou považujeme za indikátor inteli- gence (iq). jsme si vědomi toho, že kompetence a inteligence jsou v teorii odlišné koncepty, ale s ohledem na to, že mezi měřenými kompetencemi a inteligencí je velmi silný vztah [viz například desjardins, warnke ], jde podle našeho názoru o přijatelné zjednodušení, k němuž se nezřídka uchylují i někteří psy- chologové analyzující inteligenci v rámci sociologických šetření, která vždy měří inteligenci jednodušeji než klasické inteligenční testy [viz např. kanazawa ]. klíčovou proměnnou v naší analýze představuje krása, resp. atraktivita je- dince. v navazujícím výzkumu proběhlo trojí hodnocení atraktivity responden- tů. respondenti se v rámci výzkumu sami zhodnotili na jedenáctibodové škále ( – ) atraktivity, dále je na stejné škále zhodnotili tazatelé a v případech, kdy respondenti souhlasili s pořízením portrétní fotografi e ( případů), byli hodno- ceni ještě panelem hodnotitelů o členech. panel byl složen z mužů a žen ve věku od do let. pro hodnocení panelem hodnotitelů byla aplikována ačkoli mezi pojmy krása a atraktivita lze v teoretické rovině činit rozdíl, v této stati je vědomě používáme ve stejném smyslu, což vyplývá především z metody, kterou jsme na zjišťování atraktivity použili. s podobnou volností s těmito pojmy (beauty, attractiveness) pracují i zahraniční studie zabývající se vlivem krásy na úspěch na trhu práce či na životní úspěch obecně [viz např. hamermesh, biddle ; hamermesh a další]. otázka zněla: jak celkově hodnotíte svou fyzickou přitažlivost? vyberte na škále od (velmi neatraktivní) do (velmi atraktivní). otázka zněla: jak celkově hodnotíte respondentovu fyzickou přitažlivost? vyberte na škále od (velmi neatraktivní) do (velmi atraktivní). sociologický časopis / czech sociological review, , vol. , no. q-metodologie podle williama stephensona [stephenson , ]. základní metoda spočívá ve sběru dat ve formě „q-třídění“, které umožňuje analýzu pří- padů (respondentů) jako proměnných. fotografi e byly nejprve roztříděny podle technické kvality snímku a následně podle pohlaví a věkových kategorií do sku- pin zpravidla o respondentech. vzhledem k tomu, že s ohledem na předem ur- čený počet fotografi í ve skupině nebylo možné věkové kategorie defi novat zcela jednotně, byl u fotografi í ponechán údaj o věku jako pomocný údaj pro hodnoce- ní. následně byly pomocí online dotazníku fotografi e zařazené do jedné skupi- ny anonymně předloženy hodnotitelům. každou skupinu hodnotilo minimálně nezávislých hodnotitelů. jednotliví hodnotitelé portrétní fotografi e skládali do předem určeného schématu kopírujícího normální rozložení za využití sedmibo- dové škály. na krajních pólech (v tomto případě „nejvíce atraktivní“ a „nejméně atraktivní“) je nejmenší počet fotografi í ( ), ve středu největší ( ). hodnotitelé tak byli nuceni fotografi e vzájemně porovnávat, nemohli se automaticky uchýlit k neutralitě nebo podobnému hodnocení všech fotografi í. hodnocení probíhalo ve třech fázích. nejprve si hodnotitelé prostřednic- tvím online dotazníku prohlédli všechny fotografi e ve skupině. ve druhém kroku je rozdělili do tří přibližně stejně velkých skupin (nejvíce atraktivní – středně atraktivní – nejméně atraktivní). následně vybírali předem daný počet fotografi í pro konkrétní škálovou hodnotu v rámci tří skupin (které určili v předchozím kroku). umísťování fotografi í dle předem určeného schématu probíhalo tak, že nejprve byly vybrány fotografi e pro krajní škálové hodnoty a následně fotografi e pro středové hodnoty. systém byl nastaven tak, aby hodnotitel měl pro umístění na danou škálovou hodnotu k dispozici více fotografi í, než skutečně potřeboval. fotografi e, které nebyly postupně vybrány pro krajní hodnoty, dostaly automa- ticky středové hodnocení (škálová hodnota ). zvolená metoda jednak umožňuje zjistit, kteří hodnotitelé si jsou v hodnocení nejvíce podobní, a zároveň díky vyu- žití normálního rozložení respondenty diferencuje. v analytickém datovém souboru má výsledná škála atraktivity více variant, podle toho, které proměnné byly pro její konstrukci použity, a to zejména s ohle- dem na počty případů, s nimiž bylo možné a potřebné pracovat. základní škála atraktivity byla zkonstruována metodou hlavních komponent ze sebehodnocení respondenta, hodnocení tazatelem, hodnocení skupinou hodnotitelů a bmi inde- xu (index tělesné hmotnosti). nevýhodou tohoto indexu je omezený počet přípa- dů, pro které jej lze spočítat ( případů), a obtížně se s ním pracuje v analýzách skupiny ekonomicky aktivních ( případů), a to zejména provádí-li se analýza na různých podsouborech (podle pohlaví, věku atd.). pro analýzy vlivu krásy na úspěch na trhu práce proto pracujeme s indexem, do něhož nevstupuje hodnoce- ní skupinou hodnotitelů. metoda hlavních komponent ukázala velmi podobnou metoda hlavních komponent identifi kovala pouze jednu komponentu vyčerpávající % variance s následujícími faktorovými zátěžemi: sebehodnocení ( , ), hodnocení ta- zatelem ( , ), hodnocení panelem hodnotitelů ( , ) a bmi index (− , ). †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce strukturu faktorových zátěží a vyšší podíl vyčerpané variance. podstatné pro rozhodnutí pracovat s takto konstruovaným indexem byla velmi vysoká korelace s indexem založeným na všech čtyřech proměnných ( , ). počet případů, pro něž je tento „redukovaný“ koefi cient k dispozici, je mnohem vyšší ( ). sociálně-kulturní status výchozí rodiny v modelu měříme pomocí tří indi- kátorů: vzdělání otce, vzdělání matky a počet knih v domácnosti rodičů. vzdě- lání matky a otce bylo kategorizováno na tři stupně ( = nanejvýš vyučení bez maturity, = střední s maturitou, = vysokoškolské). do analýzy dále vstoupilo vzdělání respondenta, které bylo s ohledem na postupy běžné v ekonomických analýzách i v naší analýze reprezentováno počtem roků strávených formálním vzděláváním. v kauzálním modelu dále fi guruje sociálně-ekonomický status za- městnání a výdělek. obě tyto proměnné jsou měřeny způsobem běžným v ana- lýzách příjmů. pro příjem používáme průměrný hodinový výdělek včetně všech bonusů, a to v logaritmické podobě. sociálně-ekonomický status zaměstnání je reprezentován mezinárodním indexem sociálně-ekonomického statusu, který je odvozený z klasifi kace povolání isco [ganzeboom, de graaf, treiman ]. datový soubor byl v případě strukturního modelování očištěn od chybějí- cích hodnot metodou „listwise deletion“ a jako metoda odhadu parametrů mo- delu byla použita metoda maximální věrohodnosti (ml), která je doporučována i v případě výskytu standardně velkého počtu chybějících hodnot v datovém souboru [byrne ]. výpočet vychází z původní datové matice, tudíž z kovari- ančních matic příslušného počtu skupin v analýze. všechny analýzy modelu byly provedeny v programu amos (verze . .) [arbuckle ]. v zájmu korektnosti je třeba uvést, že pro dosažení srovnatelnosti modelů mezi muži a ženami a mezi věkovými skupinami jsme do modelů měření vložili předpoklad, že sociálně- -kulturní původ, celková úroveň kompetencí a atraktivita jsou mezi skupinami defi novány shodně, resp. faktorové zátěže jejich indikátorů byly zafi xovány mezi skupinami jako identické. adekvátnost takovéhoto metrického modelu je klasic- ky zjišťována prostřednictvím statistické komparace se základním (konfi gurál- ním) modelem, kde k žádným podobným restrikcím nedochází. analýza dat nejdříve se podívejme na to, zda a jak atraktivita ovlivňuje šanci na získání za- městnání s vyšším sociálně-ekonomickým statusem a výši příjmu. na rozdíl od analýz, které budou následovat, zde ukážeme výsledky za všechny ekonomicky metoda hlavních komponent identifi kovala jednu komponentu vyčerpávající % vari- ance s následujícími faktorovými zátěžemi: sebehodnocení ( , ), hodnocení tazatelem ( , ) a bmi index (− , ). pokud jde o distribuce proměnných, odkazujeme na tabulku a v příloze. sociologický časopis / czech sociological review, , vol. , no. aktivní, tj. bez ohledu na věk. výsledky uvedené v grafu možná vypadají málo přesvědčivě. uvědomíme-li si však, že index sociálně-ekonomického statusu se pohybuje v rozmezí od do bodů, přičemž nejvyšších bodů představuje absolutní špičku hierarchie zaměstnání, musíme přinejmenším připustit, že roz- díl mezi podprůměrně a nadprůměrně atraktivními je patrný, a to zejména u žen. výsledky uvedené v grafu , který ukazuje rozdíly v příjmech, jsou zají- mavější a přesvědčivější. u mužů i žen průměrný příjem s atraktivitou výrazně roste. u mužů s podprůměrnou atraktivitou je průměrný příjem pod průmě- rem a naopak, nadprůměrně atraktivní muži dosahují nadprůměrných příjmů. ještě větší rozdíly ale shledáváme u žen. zatímco podprůměrně atraktivní žena si v průměru vydělá okolo , tisíce, nadprůměrně atraktivní žena si vydělá , tisíce. tyto výsledky jsou jistě zajímavé, ale s ohledem na to, že atraktivita je feno- mén úzce provázaný s řadou dalších vlastností, které působí jak na atraktivitu sa- motnou, tak na ekonomický úspěch (například sociální původ, vzdělání či věk), nelze je chápat jinak než jako ilustraci a první přiblížení k odpovědi na otázku, zda a jak atraktivita ovlivňuje úspěch na trhu práce. dalším krokem tedy musí graf . sociálně-ekonomický status zaměstnání podle stupně atraktivity a pohlaví (průměry a intervaly spolehlivosti) , , , , , , , , , , , , , muži Ženy p rů m ěr n ý s oc io ek on om ic k ý s ta tu s podprůměrně atraktivní průměrní nadprůměrně atraktivní zdroj: Šetření – opomíjené dimenze lidského kapitálu ( ). vlastní výpočty. poznámka: nmuži = , nženy = . †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce být analýza, která atraktivitu a její působení na trhu práce (zaměstnání a příjem) zasadí do širšího kontextu a umožní minimalizovat riziko tzv. falešných korelací. tímto krokem bude, jak jsme již uvedli, strukturní modelování. detailněji popsané výsledky kauzální analýzy jsou prezentovány v tabul- ce , kde jsou uvedeny standardizované parciální regresní koefi cienty, které říkají, o kolik směrodatných odchylek se změní hodnota závisle proměnné, změní-li se hodnota nezávisle proměnné o jednu směrodatnou odchylku, a to při kont- role všech dalších proměnných, které na závisle proměnnou přímo nebo nepří- mo působí. před detailnějším rozborem výsledků můžeme konstatovat, že ženy a muži kapitalizují svou atraktivitu na trhu práce různým způsobem, což platí ze- jména pro věkovou skupinu až let. tento způsob zúročení krásy platí nejen ve fi nančním ohodnocení, ale i ve vzdělání nebo statusu zaměstnání. jak jsme již uvedli, výsledky za nejmladší a nejstarší věkovou skupinu nepodrobujeme de- výsledky modelování výše popsaných vztahů tedy čteme tak, že čím vyšší je koefi cient příslušející k danému kauzálnímu efektu, tím silnější je přímý a ničím nezprostředkovaný vliv nezávisle proměnné na závisle proměnnou. například hodnota koefi cientu , pro efekt sociálního původu na zaměstnanecký status v diagramu pro muže do let zname- ná, že změna o jednu směrodatnou odchylku sociálního původu vede ke změně o , směrodatné odchylky zaměstnaneckého statusu. graf . měsíční příjem podle stupně atraktivity a pohlaví (průměry a intervaly spolehlivosti) muži Ženy p rů m ěr n ý p ří je m podprůměrně atraktivní průměrní nadprůměrně atraktivní zdroj: Šetření – opomíjené dimenze lidského kapitálu ( ). vlastní výpočty. poznámka: nmuži = , nženy = . sociologický časopis / czech sociological review, , vol. , no. t ab u lk a . s ta n d ar d iz ov an é re gr es n í k oe fi ci en ty m et ri ck éh o k au zá ln íh o m od el u v ys vě tl u jí cí h o vý d ěl k y u e k on om ic k y ak ti vn íc h m u žů a ž en v e tř ec h v ěk ov ýc h s k u p in ác h m u ži Ž en y d o le t – le t n ad le t d o le t – le t n ad le t k om p et en ce  p ří je m − , , , , ** , − , v zd ěl án í  p ří je m , , , , , ** , ** is e i  p ří je m , , ** , ** , , ** , ** so ci ál n í p ů vo d  p ří je m , , ** , − , − , , a tr ak ti v it a  p ří je m − , , , , , ** − , * k om p et en ce  i se i − , , , ** − , , − , v zd ěl án í  i se i , ** , ** , ** , ** , ** , ** so ci ál n í p ů vo d  i se i , , , ** , , ** , a tr ak ti v it a  i se i − , , , , , ** − , v zd ěl án í  k om p et en ce , ** , ** , ** , ** , ** , ** so ci ál n í p ů vo d  k om p et en ce , ** , * , , , ** , a tr ak ti v it a  k om p et en ce − , ** , , , ** − , − , so ci ál n í p ů vo d  v zd ěl án í , ** , ** , ** , ** , ** , ** a tr ak ti v it a  v zd ěl án í , , − , , * , ** , ** so ci ál n í p ů vo d  a tr ak ti v it a , ** , * , ** − , , , n z dr oj : Š et ře ní – o po m íje né d im en ze li ds ké ho k ap it ál u ( ) . v la st ní v ýp oč ty . p oz n ám k a: m od el fi t ( m u ži ): c h i- sq u ar e = , ( d f) , p = , , g f i = , , c f i = , , r m se a = , , a ic = , ) , m od el fi t ( že ny ): c h i- sq u ar e = , ( d f) , p = , , g f i = , , c f i = , , r m se a = , , a ic = , ) . Ú ro ve ň s ta ti st ic k é si g n ifi k an ce : * * p < , , * p < , . h la d in y s ta ti st ic k é v ý zn am n os ti js ou p ou ze o ri en ta čn í, p ro to že o d h ad y ko efi c ie n tů b y ly p ro ve d en y p ou ze n a sa d ě p rv n íc h „ p la u si b le v al u es “. †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce tailním interpretacím, a to zejména proto, že velikosti těchto skupin jsou relativně malé ( , resp. případů, střední věková skupina má případů) a výsled- ky tedy postrádají potřebnou robustnost. dále se také domníváme, že v těchto věkových skupinách dochází k intervenci mnoha skrytých faktorů, které nelze spolehlivě kontrolovat. například v mladších věkových skupinách je atraktivi- ta více dílem samotného mládí než systematické péče o tělo a zevnějšek [etcoff ]. naopak v případě starších věkových skupin může výsledky zkreslovat fenomén tzv. zelených vdov, což jsou atraktivní ženy, které se vdaly za úspěš- né podnikatele a v produktivním věku se staraly výhradně o děti a domácnost, zatímco jiné ženy (možná méně atraktivní) pracovaly v placených zaměstnáních. musíme také zohlednit možnost, že tato generace je poněkud netypická, protože se jedná o ženy, které svou kariéru zahájily ještě v komunistickém režimu. z výše zmíněných důvodů se tedy dále zaobíráme především interpretací výsledků pro ekonomicky produktivní věkovou skupinu až let. z výsledků prezentovaných v tabulce je evidentní, že vliv atraktivity na úspěch na trhu práce není zanedbatelný, a to zejména u žen. Ženy ve středním věku kapitalizují atraktivitu mnohem více než muži. atraktivnější ženy ve srov- nání s méně atraktivními ženami nejenže nacházejí uplatnění v lepších pracov- ních pozicích (koefi cient , u žen vs. , u mužů), ale také více vydělávají ( , vs. , ). Ženy ve středním věku tedy zúročují atraktivitu jednak přímo ve fi nanč- ním ohodnocení své práce, ale také nepřímo přes vzdělání a lépe placené pracov- ní pozice. v této věkové skupině ženy silněji než muži kapitalizují i sociální status výchozí rodiny, a to jak v získání vyššího vzdělání ( , vs. , ), tak v sociálně- -ekonomickém statusu zaměstnání ( , vs. , ), což je v souladu s poznatky z jiných studií [diprete, buchman ], podle nichž vzdělanější, a tudíž méně konzervativní rodiče více podporují své dcery v získávání vyššího vzdělání, v umisťování se na lepších pracovních místech a také rozvíjejí jejich kompetence. nelze přehlédnout ani rozdíly v korelaci mezi vzděláním a atraktivitou, která je u žen téměř dvakrát silnější než u mužů ( , vs. , ). dané výsledky ještě více podtrhuje analýza celkových, přímých a nepří- mých efektů vlivu atraktivity na příjem, ze které vyplývá značný rozdíl mezi celkovým vlivem atraktivity na příjem u mužů a u žen ve prospěch žen ( , vs. , ) ve středním věku (viz tabulka ). zatím jsme v zájmu splnění předpokladů pro aplikaci strukturního mode- lování s atraktivitou pracovali, jako by působila „kontinuálně“ či „lineárně“. jak předchozí studie, tak životní zkušenost však ukazují, že krása a atraktivita půso- bí zřejmě jinak. zatímco průměrně krásný či atraktivní jedinec příliš nezaujme, lidé velmi nadprůměrně krásní nebo naopak výrazně oškliví pozornost přitahují. proto také většina studií doposud pracovala s nespojitými proměnnými, které vycházely z pěti či sedmibodových škál, které hodnocené jedince klasifi kovaly tyto genderové rozdíly platí i v případě, kdy v analýze nerozlišujeme mezi věkovými skupinami a provádíme ji na celé populaci žen a mužů, jen jsou o něco méně výrazné. sociologický časopis / czech sociological review, , vol. , no. od velmi krásných (strikingly handsome), přes průměrné (average looking) až po ošklivé (homely, ugly). mimo jiné i proto analýzy vlivu atraktivity na zaměstnání či příjmy vedly k poněkud kontrastnějším výsledkům, než by tomu bylo v přípa- dě využití spojitých veličin. v zájmu dosažení srovnatelnosti s předchozími studiemi jsme dále analy- zovali vliv krásy pomocí klasifi kace jedinců na nadprůměrně atraktivní (krásné), průměrné a podprůměrně atraktivní. jako nadprůměrně atraktivní jsme určili % jedinců, kteří se na škále atraktivity umístili nejvýše, obdobně jako podprů- měrně atraktivní jsme označili % nejméně atraktivních jedinců, zbývajících % jsme označili za průměr. pro srovnatelnost jsme stejně naložili i s inteligencí (resp. kompetencemi). s ohledem na výsledky strukturního modelování, které ukázaly, že jak krása, tak inteligence se na trhu práce konzistentně prosazuje až ve středním věku ( až let), tedy v době, kdy se lidé blíží vrcholu svých kariér, jsme regresní analýzy provedli jen na této skupině. analýzu jsme provedli pomocí dvou sad lineárních regresí, do nichž jako závisle proměnné vstoupil sociálně-ekonomický status zaměstnání (isei) a pří- jem vyjádřený průměrným hodinovým výdělkem včetně všech bonusů v lo- garitmické podobě (lninc), což umožňuje interpretaci výsledků v procentech průměrného příjmu. do regresních rovnic kromě atraktivity a inteligence ještě vstoupilo vzdělání respondenta v letech strávených ve škole. atraktivita a inte- ligence do rovnic vstoupila v podobě sady tzv. dummy proměnných, att_top (jedinec je nadprůměrně atraktivní), att_bot (jedinec je podprůměrně atrak- tivní), iq_top (jedinec je nadprůměrně inteligentní) a iq_bot (jedinec je pod- průměrně inteligentní). průměrně atraktivní (att_avr) a průměrně inteligentní (iq_avr) jedinci byli z analýzy vynecháni, neboť sloužili jako tzv. referenční sku- pina, tj. kategorie vůči které se ostatní skupiny porovnávají. tabulka . standardizované celkové, přímé a nepřímé regresní koefi cienty vlivu atraktivity na příjem u ekonomicky aktivních mužů a žen ve třech věkových skupinách atraktivita  příjem celkový efekt přímý efekt nepřímý efekt muži do let − , − , − , – let , , , nad let , , , Ženy do let , , , – let , , , nad let − , − , − , zdroj: Šetření – opomíjené dimenze lidského kapitálu ( ). vlastní výpočty. †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce výsledky regresní analýzy uvedené v tabulce ukazují, že atraktivita vyjá- dřená kontrastními kategoriemi používanými v běžném životě (krásný, průměr- ný, ošklivý) sice zhruba odpovídají výsledkům strukturního modelování, jsou však poněkud přehlednější. předně se ukazuje, že klíčové pro získání zaměstnání s vyšším sociálně-ekonomickým statusem je dosažené vzdělání. každý rok strá- vený ve škole zvyšuje sociálně-ekonomický status v průměru o pět bodů, přičemž rozdíl mezi muži a ženami v efektu vzdělání není veliký ( , , resp. , bodu). vliv atraktivity je podle očekávání statisticky významný. při stejném vzdělání a stejné inteligenci mají nadprůměrně atraktivní muži šanci na zvýšení sociálně- -ekonomického statusu zaměstnání o , bodu (statisticky významné zvýšení), podprůměrná atraktivita pak sociálně-ekonomický status snižuje o , bodu (bez statistické významnosti). u mužů ve středním věku je tedy statusový bonus za krásu výrazně vět- ší než statusový malus za silně podprůměrnou atraktivitu, přičemž rozdíl mezi nadprůměrně a podprůměrně atraktivním mužem je okolo osmi bodů. za po- všimnutí stojí, že téměř stejné změny vyvolává inteligence ( , , resp. − , bodu). tabulka . regresní analýza sociálně-ekonomického statusu zaměstnání (věk až let) nestandardizované koefi cienty standar- di zo va né koefi - cienty t sig. b s.e. beta muži konstanta − , , − , , vzdělání , , , , , att_top , , , , , att_bot − , , − , − , , iq_top , , , , , iq_bot − , , − , − , , Ženy konstanta − , , − , , vzdělání , , , , , att_top , , , , , att_bot − , , − , − , , iq_top , , , , , iq_bot − , , − , − , , zdroj: Šetření – opomíjené dimenze lidského kapitálu ( ). vlastní výpočty. poznámka: závisle proměnná: isei. sociologický časopis / czech sociological review, , vol. , no. zajímavé je, že u žen nehraje atraktivita v šancích na získání zaměstnání s vyšším sociálně-ekonomickým statusem tak velkou roli jako u mužů (příslušné koefi - cienty , a − , nejsou statisticky významné). vliv inteligence je u žen o něco vyšší, ale stále je nižší než u mužů. za povšimnutí ale stojí, že – ve srovnání s průměrem – je u žen malus za nízkou inteligenci výrazně větší než bonus za vysokou inteligenci. pokud tedy jde o šanci na zaměstnání s vyšším sociálně-ekonomickým sta- tusem, u mužů i žen ve středním věku hraje dominantní roli dosažené vzdělání. muži však ve srovnání s ženami v soutěži o lepší zaměstnání více zhodnocují jak vysokou atraktivitu, tak vysokou inteligenci. současně jsou ale muži ve srovnání s ženami více znevýhodňováni podprůměrnou atraktivitou. jinými slovy, bonus za vysoce nadprůměrnou atraktivitu i inteligenci, stejně jako „malus“ za silně pod prů měrnou atraktivitu je v konkurenci o dobré zaměstnání u mužů větší než u žen. získat dobré zaměstnání je však jen jedna stránka úspěchu na trhu práce. druhou, pro mnohé důležitější stránkou je příjem. v determinaci příjmu je opět tabulka . regresní analýza příjmu (věk až let) nestandardizované koefi cienty stan dar- di zované koefi - cienty t sig. b s.e. beta muži konstanta , , , , vzdělání , , , , , att_top , , , , , att_bot − , , − , − , , iq_top , , , , , iq_bot − , , − , − , , Ženy konstanta , , , , vzdělání , , , , , att_top , , , , , att_bot − , , − , − , , iq_top , , , , , iq_bot − , , − , − , , zdroj: Šetření – opomíjené dimenze lidského kapitálu ( ). vlastní výpočty. poznámka: závisle proměnná: (ln)inc. †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce nejsilnějším faktorem vzdělání, viz tabulka . u mužů každý rok vzdělání při- náší v průměru % a u žen % průměrného příjmu. bonus za nadprůměrnou atraktivitu nemají muži žádný, zato však malus za podprůměrnou atraktivitu je u mužů při stejném vzdělání a inteligenci % příjmu. při průměrném příjmu mužů okolo tisíc korun tento rozdíl činí zhruba tisíc korun ročně. u žen ve středním věku jsou ovšem rozdíly mnohem větší. bonus za nadprůměrnou atraktivitu činí u žen % průměrného příjmu, malus %, což ve výsledku zna- mená, že mezi nadprůměrně a podprůměrně atraktivní ženou je příjmový rozdíl %, což při průměrném příjmu žen okolo tisíc korun měsíčně činí okolo tisíc korun za rok. podobně je tomu i u inteligence. příjmový rozdíl mezi nad- průměrně a podprůměrně inteligentním mužem je okolo %, u žen je %. v konkurenci o dobré zaměstnání tedy jak krása, tak inteligence zvýhodňu- je více muže než ženy, u příjmů je tomu naopak. České ženy berou zhruba o % méně než muži, ale jak ukazuje graf , největší rozdíl mezi průměrnými příjmy mužů je v kategorii určené podprůměrnou atraktivitou i inteligencí. nadprů- měrně atraktivní a inteligentní ženy však mají stejné příjmy jako nadprůměrně atraktivní a inteligentní muži, resp. o tři tisíce muže „poráží“, rozdíl však není sta tisticky významný. graf . příjmy mužů a žen podle zařazení do kategorií defi novaných inteligencí a atraktivitou (průměry a intervaly spolehlivosti) – věková skupina až let zdroj: Šetření – opomíjené dimenze lidského kapitálu ( ). vlastní výpočty. poznámka: nmuži = , nženy = . muži Ženy muži Ženy muži Ženy nejnižších % iq % okolo průměru iq nejvyšších % iq p rů m ěr n ý p ří je m podprůměrně atraktivní průměrní nadprůměrně atraktivní sociologický časopis / czech sociological review, , vol. , no. závěry hlavním cílem této stati bylo prověřit, zda krásu, resp. atraktivitu lze považovat za kapitál, který se neobejde bez určitých investic, ale jestliže již jednou existuje a je udržován, působí na trhu práce podobně jako jiné kapitály či vlastnosti, které se jako kapitál „chovají“. ačkoli je zřejmé, že tohoto cíle bylo dosaženo, některé z výsledků si zaslouží ještě jednou shrnout a uvést do širších souvislostí. předně se zdá být evidentní, že atraktivnější lidé mají větší šanci na zaměst- nání s vyšším sociálně-ekonomickým statusem a na vyšší příjem než lidé méně atraktivní. podstatné je, že viditelný vliv atraktivity na zaměstnání a příjem ne- zmizí, ani když do „hry“ zapojíme dosažené vzdělání, kompetence (inteligenci), věk a sociální původ. i když, zcela hypoteticky, porovnáváme jedince se stejným vzděláním, stejnou inteligencí, stejným sociálním původem a ve zhruba stejném věku, atraktivita sama o sobě působí jako „kapitál“, který trh práce zhodnocuje. k podstatným zjištěním patří i to, že krása a atraktivita se nejvíce prosazuje, ve středním věku, kdy se lidé postupně blíží vrcholům svých kariér nebo jich již dosáhli. v této skupině se pak nejvíce projevují rozdíly mezi muži a ženami. zde musíme rozlišovat mezi kapitalizací krásy v konkurenci o lepší zaměstnání (tj. zaměstnání s vyšším sociálně-ekonomickým statusem) a v příjmech. pokud jde o získání zaměstnání s vyšším sociálně-ekonomickým statusem, kapitalizovat atraktivitu se daří spíše mužům než ženám, přičemž bonus za krásu zde jedno- značně převažuje nad malusem za nízkou atraktivitu. totéž ovšem platí o inteli- genci. u žen jsou tyto principy působení krásy a inteligence stejné, jen jejich vlivy jsou slabší. zcela odlišná situace je u příjmů. ačkoli muži nemají za nadprůměrnou atraktivitu žádný bonus, za podprůměrnou atraktivitu jsou příjmově „trestá- ni“ více než ženy (příjmový propad způsobený podprůměrnou atraktivitou je u mužů %, u žen %). zásadní rozdíl je ovšem v bonusech za nadprůměrnou atraktivitu i inteligenci. bonus za nadprůměrnou atraktivitu činí u žen % prů- měrného příjmu, malus %, což vede k celkovému příjmovému rozdílu mezi atraktivními a neatraktivními ženami ve výši % průměrného příjmu. to při průměrném příjmu žen okolo tisíc korun měsíčně činí okolo tisíc za rok a zhruba jeden milion za dvacetiletou pracovní kariéru. podobně je tomu u inte- ligence: příjmový rozdíl mezi nadprůměrně a podprůměrně inteligentní ženou je % průměrného příjmu, a to při kontrole vzdělání i atraktivity. jak jsme již uvedli, u mužů jsou tyto efekty výrazně slabší. příjmový rozdíl mezi nadprůměr- ně a podprůměrně atraktivním mužem ve středním věku je %, což při průměr- ném příjmu mužů okolo tisíc korun činí zhruba tisíc korun ročně, což za dvacetiletou pracovní kariéru činí okolo půl milionu korun. muži si ve srovnání se ženami příliš nepolepší ani nadprůměrnou inteligencí, její čistý vliv na příjem je ve srovnání se ženami poloviční. z provedených analýz je tedy zřejmé, že kapitál spojený s krásou a atrak- tivitou se v České republice ženám vyplácí více než mužům, přičemž „trest za †petr matějů, petra anýžová: krása jako kapitál: role atraktivity v úspěchu na trhu práce ošklivost“, na němž naomi wolfová [ ] postavila svoji tezi o kráse jako „patri- archálním mýtu zotročujícím ženy“, je paradoxně větší u mužů než u žen. v tom- to smyslu jsou závěry z našich analýz velmi podobné těm, k nimž na datech ze spojených států a kanady dospěli hamermesh a biddle [ ]. k tomu bychom však dodali, že strukturní modelování ukázalo, že z metodologického hlediska je vhodnější měřit dané příčinné vazby na populaci ve středním věku, kdy fyzická atraktivita již není převážně atributem mládí a vyžaduje určitou, zpravidla syste- matickou, péči. navíc v tomto věku se lidé blíží vrcholům svých pracovních kari- ér a je tedy logické, že na trhu práce nejvíce – vědomě či nevědomě – zhodnocují všechny „kapitály“, které dříve akumulovali. naše výsledky dále nepotvrzují zjištění z výzkumů provedených ve spo- jených státech a v kanadě, podle nichž výjimečnou fyzickou atraktivitu v pří- jmech zhodnocují více muži než ženy. u nás je tomu naopak, přičemž rozdíly ve prospěch žen jsou značné. ani náš výzkum nepotvrdil statisticky významnou souvislost mezi fyzickou atraktivitou na jedné straně a ekonomickou aktivitou a rodinným stavem na straně druhé. tedy ani v našem případě se tak vysvětlení genderových rozdílů ve vlivu atraktivity na úspěch na trhu práce různou mírou participace na trhu práce nejeví jako plausibilní. vše tedy nasvědčuje tomu, že zatímco vliv fyzické atraktivity na úspěch na trhu práce je nezanedbatelný a kul- turně univerzální, genderové rozdíly v působení fyzické atraktivity se naopak zdají být kulturně specifi cké. tento závěr samozřejmě bude vyžadovat hlubší teo retický i empirický rozbor, který však přesahuje možnosti této stati. petr matĚjŮ byl profesorem sociologie. v posledních letech působil jako ředitel univer- zitního výzkumného centra vysoké školy fi nanční a správní. v roce založil institut pro sociální a ekonomické analýzy (isea). zabýval se zejména sociálními nerovnostmi, sociální stratifi kací, mobilitou, lidským kapitálem a sociální spravedlností. petr matějů zemřel po dlouhé nemoci v průběhu redakčního zpracování tohoto článku . června ve věku let (pozn. red.). petra anÝŽovÁ absolvovala doktorské studium sociologie na filozofi cké fakultě univerzi- ty karlovy a v současnosti pracuje jako vědecký pracovník v sociologickém ústavu av Čr a jako odborná asistentka na vysoké škole fi nanční a správní. jejími výzkumnými zájmy jsou metodologie mezinárodních výzkumů, vzdělanostní a sociální nerovnosti, lidský ka- pitál a problematika hodnotových orientací. literatura anýžová, p. . srovnatelnost postojových škál v komparativním výzkumu. olomouc: univerzita palackého v olomouci. arbuckle, j. l. . ibm spss® amos™ user’s guide. amos development corporation. crawfordville, fl. sociologický časopis / czech sociological review, , vol. , no. averett, s. l., s. korenman. . „the economic reality of the beauty myth.“ journal of human resources ( ): – , https://doi.org/ . / . 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this development has been boosted, in particular, by the now well-established atmospheric neutrino anomaly, but also solar neutrinos and neutrinos in the early universe are discussed in this context. in this paper we concentrate on possible decoherence effects which might arise due to some fundamental modification of qm or due to the interaction of the system with its “environment”, whatever this may be. in the latter case, the idea of the influence of quantum gravity [ , ] – quantum fluctuations in the space-time structure at the planck mass scale – is especially attractive nowadays. possible effects of the environment have been investigated intensively in the k k̄ system in refs. [ , – ]. but also other models of decoherence, like those found in refs. [ – ], may serve as working hypothesis. our model, which we will propose in this paper, has some remote similarity with the models mentioned here, but ours will be tailored to the situation of two particles moving apart in their center of mass system. in the past, a measure of decoherence for entangled systems has been introduced on pure phenomenological grounds in order to determine quantitatively deviations from pure qm. this simple procedure of multiplying the quantum-mechanical interference term by −ζ [ ], where ζ is called decoherence parameter, is a basis-dependent concept and works very well as a measure for interpolating continuously between pure qm (ζ = ) and total decoherence (ζ = ). the latter case corresponds to spontaneous factorization, also called furry’s hypothesis [ ]. by investigating certain observables, the authors of refs. [ – ] could show that the entangled k k̄ and b b̄ systems are far from total decoherence, at least when ζ is introduced in relation to the basis of mass eigenstates, so that local realistic theories are highly unlikely. in other words, the presence of the interference term is well established in agreement with qm (see also ref. [ ]), which means that there is quantum interference of massive particles over macroscopic distances. in this paper we want to present a model of dissipation for entangled systems of two particles. in contrast to the prevailing concept in the literature, where dissipation is in- troduced at the -particle level and transferred to the -particle level through the tensor product structure of the hilbert space of states (see, e.g., ref. [ ]), we assume the usual quantum-mechanical time evolution for the -particle states. thereby we have in mind that entangled -particle systems become decoherent when they move apart over macroscopic distances, whereas for a -particle system qm is not modified. our dissipative term in the -particle time evolution obeys the condition of complete positivity [ ]. for reasons given below, we consider the entangled b b̄ system with negative c parity. by using the exper- imental value of the ratio r of the number of like-sign dilepton events over opposite-sign dilepton events, we can derive a bound on the strength of the dissipative term. considering the time-integrated dilepton event rates, our model reproduces precisely the corresponding calculations with the phenomenological decoherence parameter ζ associated with the bh - bl basis. as a result, we obtain a remarkably simple formula which relates the dissipative strength to the decoherence parameter ζ. in the context of the observable r, we also com- pare our model of -particle decoherence with the case where the analogous dissipative term is introduced already at the -particle level. ii. the model before considering the b b̄ system, let us first discuss our model of decoherence in a -dimensional hilbert space of states h = c . we allow for a non-hermitian hamiltonian h, in order to include the possibility of incorporating particle decay in the weisskopf–wigner approximation [ ]. we denote the normalized energy eigenstates by |ej〉 (j = , ) and have, therefore, h|ej〉 = λj|ej〉 with λj = mj − i Γj , ( . ) where mj and Γj are real and the latter quantities are positive in addition. furthermore, we make the crucial assumption that 〈e |e 〉 = ( . ) despite the non-hermiticity of h. including decoherence, the time evolution of the density matrix ρ has the form dρ dt = −ihρ + iρh† − d[ρ] . ( . ) our model of decoherence consists in assuming that d[ρ] = λ (p ρp + p ρp ) , where pj = |ej〉〈ej| ( . ) and λ is a positive constant. such a term is also employed, for instance, in the context of neutrinos in the early universe (see, e.g., ref. [ ]). it can readily be checked that the decoherence term in eq. ( . ) is of the lindblad type [ ] d[ρ] = (∑ j a † jajρ + ρ ∑ j a † jaj ) − ∑ j ajρa † j , ( . ) if we make the identification aj = √ λpj . thus, the term ( . ) generates a completely positive map; moreover, since p † j = pj and [pj,h] = , the decoherence term would increase the “von neumann entropy” and conserve energy in the case of a hermitian hamiltonian (see ref. [ ] and references therein). however, what is more important in our discussion is the fact that with the choice ( . ) the equations for the components of ρ decouple. indeed, with ρ = ∑ j,k= ρjk|ej〉〈ek| , ( . ) where ρjk = ρ ∗ kj , and with the time evolution ( . ), we obtain ρ (t) = ρ ( ) exp(−Γ t), ρ (t) = ρ ( ) exp(−Γ t), ρ (t) = ρ ( ) exp {−[i(m − m ) + (Γ + Γ )/ + λ] t} . ( . ) let us for a moment dwell on the motivation for our model of decoherence. to this end we start with the more general setting aj = √ λjpj (j = , and λj > ) with pj = |pj〉〈pj|, where the normalized vectors |pj〉 are linearly independent and in general different from the eigenvectors of the hamiltonian. note that we also allow for 〈p |p 〉 = . in any case, one can use formula ( . ) to obtain a completely positive dissipative term in the time evolution ( . ), but in general one will not obtain the form of d[ρ] given by eq. ( . ). for the time being we want to assume that h† = h = holds and that h is non-degenerate in order to avoid trivial considerations. now we have two possibilities: . the system {|p 〉, |p 〉} is the system of eigenvectors of h, i.e., it is equivalent to the orthonormal system {|e 〉, |e 〉}; . {|p 〉, |p 〉} is not equivalent to the system of eigenvectors of h. in the first case one can show that the form ( . ) of d[ρ] with λ = (λ + λ )/ is obtained and that case ⇔ [h,pj ] = for j = , : lim t→∞ ρ(t) = p ρ( )p + p ρ( )p ( . ) holds. furthermore, density matrices pj , or linear combinations thereof, are constant solu- tions of the time evolution equation. in the second case, at least one of the vectors |p 〉, |p 〉 is not an eigenvector of h and one can prove that case ⇔ ∃j = or with [h,pj ] = : lim t→∞ ρ(t) = , ( . ) independent of ρ( ). we will see in the following – when we apply our model to the b b̄ system – that the first case is closer to our physical intuition (see also last paragraph of this section). the two cases have been described in refs. [ , ] in the context of -particle decoherence in neutrino oscillations. note that case is used in ref. [ ] (see also ref. [ ]), whereas case is considered, e.g., in ref. [ ] in the same context. if we allow for h† = h, the picture, we have developed here, gets blurred because then there is a competition between particle decay, i.e., limt→∞ tr ρ(t) = , and the effect of decoherence. we nevertheless stick to the first case. note that identifying the orthonormal system given by pj (j = , ) with the system of eigenvectors of h is not only motivated by the considerations above but also by simplicity; as we have seen in eq. ( . ) we have decoupled time evolutions as a consequence. we want to stress, however, that in the case of cp violation, which is particularly important for the k k̄ system, it might be useful to allow for small deviations from 〈e |e 〉 = , and thus for small deviations of the eigenvectors of the hamiltonian from the orthonormal system {|p 〉, |p 〉}. returning from general considerations, we now we apply our model of decoherence to the case of the -particle b b̄ state, generated by the decay of the Υ( s) resonance (for the formalism used in the b b̄ system see, e.g., ref. [ ]). we conceive t as the eigentime of b and b̄ and make the identification |e 〉 = |bh ⊗ bl〉 and |e 〉 = |bl ⊗ bh〉 , ( . ) where the heavy and the light neutral b states are defined via |bh〉 = p|b 〉 + q|b̄ 〉 and |bl〉 = p|b 〉 − q|b̄ 〉 , ( . ) which have eigenvalues λh = mh − i Γh and λl = ml − i Γl , ( . ) respectively, of the effective -particle hamiltonian h . for the -particle system, we trans- fer, as usual, the -particle hamiltonian to the tensor product of the -particle hilbert spaces by using h = h ⊗ + ⊗h . we imagine that the first factor in the tensor product corresponds to particles moving to the left, whereas the second factor in the tensor prod- uct corresponds to right-moving particles. we assume cp conservation in b -b̄ mixing, which is a good approximation [ , ] and corresponds to |p/q| = . in this case we have 〈bh|bl〉 = and, therefore, 〈e |e 〉 = . in the following we will set p = q = / √ . at the Υ( s) resonance, at t = , the entangled state |ψ〉 = √ (|e 〉 − |e 〉) ( . ) is produced, which is equivalent to the density matrix ρ( ) = (|e 〉〈e | + |e 〉〈e | − |e 〉〈e | − |e 〉〈e |) . ( . ) with the time evolution ( . ), the initial condition ( . ) and taking into account that in the case of the vectors ( . ) we have λ = λ = mh + ml − iΓ with Γ ≡ (Γh + Γl)/ , we obtain the time evolution ρ(t) = e− Γt { |e 〉〈e | + |e 〉〈e | − e−λt (|e 〉〈e | + |e 〉〈e |) } . ( . ) note that the factor exp(−λt) in the density matrix ( . ) introduces decoherence as a consequence of the d-term in the time evolution ( . ). in other words, for t > and λ > , the density matrix ( . ) does not correspond to a pure state anymore. having chosen the energy eigenstates ( . ) for the construction of the projectors pj , our model complies with case ( . ). in this case, we would have no decoherence if ρ( ) = p or p , though such initial conditions might be unrealistic. this agrees with our intention because in these cases we have no entanglement over macroscopic distances and no reason for modifying the quantum-mechanical time evolution. note that using the projector states ( . ) confines our hilbert space of states to a -dimensional one. using projector states which are non-trivial orthogonal linear combinations of the states ( . ), would lead to case ( . ), still with a -dimensional hilbert space. however, using projector states which are not linear combinations of the states ( . ), like, e.g., |b ⊗b̄ 〉, |b̄ ⊗b 〉, entails not only a time evolution into the full -dimensional hilbert space of states, including |bh ⊗ bh〉 and |bl ⊗ bl〉, but also opens up the possibility for more involved schemes of decoherence than given by our simple model. iii. the measurement in order to obtain information on the parameter λ, which modifies the time evolution in the b b̄ system, we adopt the following philosophy. we start at t = with the density matrix ( . ) for a b b̄ state with negative c parity. this -particle density matrix follows the time evolution ( . ) and undergoes thereby some decoherence. we imagine a measurement of the b quantum number of the left-moving particle at time t` and of the right-moving particle at time tr. for times min(t`, tr) < t < max(t`, tr) we have a -particle state which we assume to evolve exactly according to qm, with the time evolution given by h . in a mathematical language, we do the following. assuming for definiteness t` < tr, at t = t` we calculate the trace tr` {(|n〉〈n| ⊗ ) ρ(t`)} ≡ ρr(t`; t = t`) , ( . ) where tr` means the trace evaluated only in the space of the left-moving particles; ρ(t`) is given by eq. ( . ), evaluated at t = t`; moreover, we have defined | 〉 = |b 〉 and | 〉 = |b̄ 〉, and n = , . consequently, ρr(t`; t = t`) is a -particle density matrix for the right-moving ones. for t > t`, it is denoted by ρr(t`; t) and follows the -particle time evolution. at t = tr, where we measure the b quantum number of the right-moving particles, we finally have (n′ = , ) n(n,t`; n ′, tr) = tr {|n′〉〈n′|ρr(t`; tr)} . ( . ) using all the above formalism and allowing also for t` > tr, we arrive at n(n,t`; n ′, tr) = e−Γ(t`+tr ) × { |〈n|bh〉| |〈n′|bl〉| e−∆Γ(t`−tr )/ + |〈n|bl〉| |〈n′|bh〉| e∆Γ(t`−tr )/ −e−λ min(t`,tr ) ( 〈n|bh〉〈n|bl〉∗〈n′|bl〉〈n′|bh〉∗e−i∆m(t`−tr ) + 〈n|bl〉〈n|bh〉∗〈n′|bh〉〈n′|bl〉∗ei∆m(t`−tr ) )} . ( . ) in this equation we have used the notation ∆Γ = Γh − Γl and ∆m = mh − ml. for the sake of clarity, we have retained the scalar products 〈n|bh,l〉 and 〈n′|bh,l〉. according to our assumption of cp conservation in b -b̄ mixing, we will replace them by their values ± / √ . it is easy to check that for λ = one obtains the usual expressions found in the literature. note that for t` = tr and n = n ′ we have n(n,t`; n,t`) = e− Γt` ( − e−λt` ) , ( . ) which is different from zero, in contrast to the standard quantum-mechanical case. iv. the dileptonic decays in practice, measurement of the b quantum number of neutral mesons in the entangled b b̄ state proceeds via flavour tagging when the mesons decay. assuming the validity of the ∆b = ∆q rule, in inclusive semileptonic decays `+ tags b and `− tags b̄ (` = e or µ). in the following we will concentrate on dilepton events [ ]. denoting the inclusive semileptonic decay rate by Γ`, the numbers of dilepton events from the decay of |ψ〉 ( . ) are then given by the integrals n++ = Γ ` ∫ ∞ dt` ∫ ∞ dtr n( , t` ; , tr) , n−− = Γ ` ∫ ∞ dt` ∫ ∞ dtr n( , t` ; , tr) , n+− = n−+ = Γ ` ∫ ∞ dt` ∫ ∞ dtr n( , t` ; , tr) . ( . ) defining x = ∆m/Γ and y = ∆Γ/ Γ and calculating these integrals leads to the result n++ = n−− = Γ ` Γ { − y − + x ( − ζ(Λ)) } , ( . ) n+− = n−+ = Γ ` Γ { − y + + x ( − ζ(Λ)) } , ( . ) where the function ζ(Λ) is given by the simple expression ζ(Λ) = Λ + Λ with Λ = λ Γ . ( . ) it is interesting to note that x does not enter into ζ. eqs. ( . ) and ( . ) reproduce the results of refs. [ , ], where the “decoherence pa- rameter” ζ [ ] is introduced phenomenologically in the observable r = n++ + n−− n+− + n−+ , ( . ) by multiplying the interference terms in n++, etc., with ( − ζ). in the model presented here, ζ is expressed by the parameter λ (see eq. ( . )), the strength of the dissipative term in the modified time evolution ( . ). it has been discussed in the literature that the above phenomenological procedure of introducing a parameter ζ depends on the basis chosen in b -b̄ space [ , – , ]. in the present model it is the ζ associated with the bh -bl basis. let us perform a numerical estimate of ζ and Λ along the lines presented in ref. [ ]. to this end we use r ( . ), which has been measured by the argus [ ] and cleo [ ] collaborations. combining both measurements, we obtain the value rexp = . ± . [ ]. as far as x is concerned, we use the value xexp = . ± . obtained by combining the data from all lep experiments [ ]. with the approximation y = in eqs. ( . ) and ( . ) [ , ] and using the law of propagation of errors, from rexp and xexp we derive the following numerical estimates: ζ = − . ± . and Λ = − . ± . . ( . ) the belle collaboration has published data on the correlated semileptonic decay rate as a function of the difference t` −tr [ ]. of course, these data could also be used to put a limit on λ, if we integrate n(n,t`; n ′, tr), eq. ( . ), over t` + tr. however, we do not have enough information to perform such a fit. let us now compare our model, where decoherence is implemented at the -particle level, with the case where we have the analogous time evolution ( . ) at the -particle level [ , ]. we use the same structure of the d-term as given by eq. ( . ), but now with |e 〉 = |bh〉 and |e 〉 = |bl〉, instead of eq. ( . ). we denote the strength of the dissipative term by ξ, in order to distinguish it from λ in the case of -particle decoherence. evidently, we have the same time evolution ( . ) at the -particle level, with λ replaced by ξ. following the steps to derive eq. ( . ), we obtain the same formula, except that exp(−λ min(t`, tr)) is replaced by exp(−ξ(t` + tr)). eventually, we arrive at n++ and n+− given by eqs. ( . ) and ( . ), respectively, where ζ is now given by ζ(Ξ,x) = ( + Ξ) − ( + Ξ) + x with Ξ = ξ Γ . ( . ) thus the two models of decoherence cannot be distinguished on the basis of the time- integrated dilepton event rates, but only on the basis the time-dependent event rates. a numerical estimate analogous to the one performed for Λ leads to the result Ξ = − . ± . . v. the summary in this paper we have considered a model of decoherence applicable in the center of mass system of two particles. our model reflects the idea that, when the two particles move apart and eventually become macroscopically separated, some “forces” might be operative which de-entangle the quantum-mechanical state as a function of the distance. the dissipative term which we have added to the quantum-mechanical time evolution could be an effective term originating in some modification of qm; it could as well be based on some effective quantum-mechanical description of an interaction of the -particle system with an unknown environment. our dissipative term respects complete positivity, which – we believe – is a useful physical guiding principle for modifications of the quantum-mechanical time evolution. in compliance with our idea, we assume that, after one of the particles has decayed, the other one follows the quantum-mechanical time evolution. we have applied our model in the case of the entangled b b̄ state with negative c parity, where we have used the data on the b lifetime, the bh -bl mass difference measured by observing the time evolution of single neutral b mesons, and the ratio of like-sign over opposite-sign dilepton event rates note that the result for r with ζ given by eq. ( . ) agrees with the result for r in first order in Ξ of ref. 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[ ] a.j. buras, w. s lominski and h. steger, nucl. phys. b , ( ). [ ] k. abe et al., belle coll., arxiv:hep-ex/ . the difficult beauty of mansfield park the difficult beauty of mansfield park author(s): thomas r. edwards, jr. source: nineteenth-century fiction, vol. , no. (jun., ), pp. - published by: university of california press stable url: http://www.jstor.org/stable/ accessed: / / : your use of the jstor archive indicates your acceptance of jstor's terms and conditions of use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. jstor's terms and conditions of use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the jstor archive only for your personal, non-commercial use. please contact the publisher regarding any further use of this work. publisher contact information may be obtained at http://www.jstor.org/action/showpublisher?publishercode=ucal. each copy of any part of a jstor transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. jstor is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. we use information technology and tools to increase productivity and facilitate new forms of scholarship. for more information about jstor, please contact support@jstor.org. university of california press is collaborating with jstor to digitize, preserve and extend access to nineteenth-century fiction. http://www.jstor.org http://www.jstor.org/action/showpublisher?publishercode=ucal http://www.jstor.org/stable/ ?origin=jstor-pdf http://www.jstor.org/page/info/about/policies/terms.jsp http://www.jstor.org/action/showpublisher?publishercode=ucal the diffcult beauty of mansfield park thomas r. edwards, jr. from the reverend james stanier clarke on, there have been those who see no problem in mansfield park; it is a pleasing tale of virtue rewarded, and this is enough. but such readers are happily rarer today than a hundred years ago; some of our best critical minds have boggled at accepting fanny price and jane austen's endorsement of her,' and the novel's difficulties have to be faced. even its admirers have had to season their praise-often for "technical" successes-with uneasy confessions that its moral frame may be simpler than the fictional life it controls and judges. only lionel trilling observes that such uneasiness marks the prime virtue of the novel, whose greatness is "commensurate thomas r. edwards, jr., is a member of the department of english, rutgers university. for good statements of the case against the novel, see: d. w. harding, "regu- lated hatred," scrutiny, viii ( ), - (reprinted, with other valuable essays, in the excellent collection discussions of jane austen, ed. william heath [boston, ], pp. - ); c. s. lewis, "a note on jane austen," essays in criticism, iv ( ), - (heath, pp. - ); and the pertinent chapter in marvin mudrick, jane austen: irony as defense and discovery (princeton ). mr. mudrick's is the most uncompromising condemnation, and the most carefully analytical; my reading (and, i suspect, lionel trilling's too) was in large part arrived at by trying to answer his objections, and i take this to indicate how vigorous and intelligent his case is, even though i almost entirely disagree with it. all quotations from mansfield park are from the edition of r. w. chapman, nd ed. (oxford, ); i give page references to this edition, and (in roman nu- merals) chapter references to the numerous other editions which (unlike dr. chap- man's) number the chapters consecutively, without regard for the original three- volume form. see, for example, reginald farrer, "jane austen," quarterly review, ccxxvii ( ), - (heath, pp. - ); joseph m. duffy, jr., "moral integrity and moral anarchy in mansfield park," elh, xxiii ( ), - ; charles murrah, "the background of mansfield park," in from austen to joseph conrad, ed. r. c. rath- burn and martin steinmann, jr. (minneapolis, ), pp. - ; and andrew h. wright, jane austen's novels, rev. ed. (london, ), pp. - . lionel trilling, "mansfield park," in the opposing self (new york, ) (heath, pp. - ). my dissents from mr. trilling's views will not, of course, dis- guise the extent of my indebtedness to his indispensable essay. [ ] nineteenth-century fiction with its power to offend." one learns more about mansfield park from mr. trilling than from anyone else; but while i share his belief in its greatness, i must confess some doubts about his way of reading it. although fanny is indeed conceived ironically, i think jane austen likes her and wants us to like her too-and despite mr. trilling's invocation of "the shade of pamela," i find it quite possible to do so. nor can i accept his view of henry and mary crawford; surely they are presented consistently, and with entire persuasiveness, as being more gravely flawed and less charm- ing than he finds them, even at first reading; and in mary, espe- cially, jane austen diagnoses a moral disorder that, because less under conscious control, is both more alarming and more pitiful than the deliberate insincerities and impersonations with which he charges them. in short, mr. trilling concedes too much to the opposition, even to the extent of accepting the idea that the novel's praise "is not for social freedom but for social stasis," that it rejects "spiritness, vivacity, celerity, and lightness . .. as having nothing to do with virtue and happiness." fanny and edmund do reject freedom and vivacity, to be sure, and they are right to do so, considering who they are, but jane austen's view of the rejection is considerably more complicated and troubled than theirs. mansfield park does speak, as mr. trilling says, "to our secret inexpressible hopes" of escaping the "demands of personality" and secular complexity, but it warns as well that such an escape would cost us dearly. it is first of all a singularly "beautiful" novel, one in which jane austen draws more than usual upon "scenic" resources. we attend more to where people are and what they are doing, and, more important, scene makes fuller contact with moral meaning. the excursion to sotherton reveals this mingling of scene and meaning at its fullest. in contravention of mrs. norris' plans for organized sightseeing, the young people, meeting with an outward door, temptingly open on a flight of steps which led immediately to turf and shrubs, and all the sweets of pleasure-grounds, as by one impulse, one wish for air and liberty, all walked out (p. , ix). the tangled syntax reflects another entanglement, of motive and this is the point of mr. murrah's essay; both he and mr. duffy say that the sotherton episode is important. the difficult beauty of mansfield park evaluation, which the setting expresses too: it is good to thwart mrs. norris and all calculations about pleasure, yet the "impulse" seems too easily satisfied, the "sweets" too "immediate." (are not gardens "tempting" places?) guests should wait for invitations, but more than good manners seems at issue. there follows a dance-like movement through the landscape of lawn, wilderness, and park, in which personal groupings, and the romantic possi- bilities they imply, dissolve and reform; henry and maria slip into the locked park, jealously followed by julia and rushworth; mary and edmund rejoin a lonely fanny and are welcomed back by authority in an amusingly theatrical tableau: "on [their] reaching the bottom of the steps to the terrace, mrs. rushworth and mrs. norris presented themselves at the top" (p. , x). happily, it is not the novelist but the characters who seek to exploit the scene's obvious symbolic possibilities. mary, for one, has a lively sense of what might be done with the landscape: "we have taken such a very serpentine course; and the wood itself must be half a mile long in a straight line, for we have never seen the end of it yet, since we left the first great path. "but if you remember, before we left that first great path, we saw directly to the end of it. we looked down the whole vista, and saw it closed by iron gates, and it could not have been more than a furlong in length." "oh! i know nothing of your furlongs, but i am sure it is a very long wood; and that we have been winding in and out ever since we came...." "we have been exactly a quarter of an hour here," said edmund, taking out his watch. "do you think we are walking four miles an hour?" "oh! do not attack me with your watch. a watch is always too fast or too slow. i cannot be dictated to by a watch" (pp. - , ix). mary wants the wilderness to be a forest of love (or at least dalliance); her terms-serpentine course, first great path, not seeing to the end of it-playfully hint at an allegory of possible emotional involvement. she aims at a charming "femininity," but her projection of the scene as a spenserian forest where time and space are suspended seems strained and coy. if edmund (as so often) misses the point with his blundering addition of the iron gates and his inept insistence on furlongs and watches, we must nineteenth-century fiction still agree that time and space do exist, both as they affect people (fanny is tired) and in their resonances as moral metaphors-to romanticize like this is to risk losing your bearings. the danger becomes clear when henry and maria stand foiled by the gate: "your prospects, however, are too fair to justify want of spirits. you have a very smiling scene before you." "do you mean literally or figuratively? literally i conclude. yes, certainly, the sun shines and the parks looks very cheerful. but un- luckily that iron gate, that ha-ha, gives me a feeling of restraint ancl hardship. i cannot get out, as the starling said." as she spoke, and it was with expression, she walked to the gate; he followed her. "mr. rushworth is so long fetching this key!" "and for the world you would not get out without the key and with- out mr. rushworth's authority and protection, or i think you might with little difficulty pass round the edge of the gate, here, with my assistance; i think it might be done, if you really wished to be more at large, and could allow yourself to think it not prohibited." "prohibited! nonsense! i certainly can get out that way, and i will" (p. , x). this innuendo-ridden talk is what edmund's stolid belief in time and space unwittingly saved him from. jane austen predicts the final disaster of maria and henry, but the moment evokes views of obligation and licence that are more than aspects of "plot" or "character." freedom is tempting because it may be wicked. each -henry slyly, maria impetuously-uses the setting to mirror improper interest in the other; since neither admits that the conversation is "figurative," they can dally with perfect efficiency (for both, getting into the park easily becomes "getting out") with- out taking any responsibility for their insinuations. people who imply that they mean more than they say, yet refuse to say what they mean, are both irritating and dishonest, and fanny, though as usual she can't quite say it, senses thoroughly what is at stake: "you will certainly hurt yourself against those spikes-you will tear your gown-you will be in danger of slipping into the ha-ha. you had better not go." setting becomes the image of moral violence. the whole episode is beautifully drawn, but like other great moments in mansfield park it represents more than a local triumph of "technique," to be weighed against a pervasive failure of dis- the difficult beauty of mansfield park crimihiation and understanding by the author.- the beauty of the novel, its brilliant combining of jane austen's usual mastery of speech and incident with a new sense of what setting can express, serves the end of a subtler statement and development of the novelist's grasp of the fictional "life" she deals with. though it would be hard to prove, i think we are told less in this novel than in her others; evaluations are less clear-cut, judgments less re- liant on any moral schematism, significance more dependent on. our "reading" of scenes. if we look in fanny for the signs that so firmly place jane austen's other heroines we will not find them, nor are edmund, mary, and henry so distinctly given moral location. but this blurring of the outlines of comedy of manners (or fairytale) creates not confusion but a new generosity and seriousness in the presentation of "theme." the theme presented has to do with meddling, seeking to impose one's will on creatures entitled to wills of their own, treating other lives as though one's designs for them were their chief reason for being. stated so broadly, this is the theme of emma and, it less prominently, of the other novels too; at this level of generality, indeed, it is the theme of most classic fiction and many of our difficulties with life. but in mansfield park it gets a fullness of treatment not to be equalled until the triumphs' of george eliot and james. there is first mrs. norris, whose selfish meddling is the novelist's hint of deeper significance elsewhere. miss lascelles remarks that her favorite phrase is "between ourselves," "with its suggestions of conspiracy and wire-pulling"; to this might be added the set of variations-"i perfectly comprehend you," "i entirely agree with you," "that is exactly what i think," etc.-that at least once reveals its theme: " 'if i were you' " (p. , vi). mrs. norris, in other ways demonstrably jane austen's most nearly psychotic creation, yearns to merge with other existences, and she deeply resents resistence: [fanny] likes to go her own way to work; she does not like to be dic- both mr. harding and mr. lewis suggest cinderella as a pattern for fanny prike.,ut -edmund, her reward for suffering, is hardly a prince charming; it -is the' crawfords, not jane austen, who impose fantasy upon truth. barbara bail collins, "jane austen's victorian novel," nineteenth-century fiction, iv,( ), - , recognizes that mansfield park anticipates some of the methods of victorian fiction, but in her view it is "a forerunner of the dowdy propriety and piety which blossomed in the 'fifties." mary lascelles, jane austen and her art (oxford, ), p. . nineteenth-century fiction tated to; she takes her own independent walk whenever she can; she certainly has a little spirit of secrecy, and independence, and non- sense, about her, which i would advise her to get the bettter of (p. , xxxii). although sir thomas, recently guilty of the same view, thinks this unjust, mrs. norris has put her finger on something. behind her softness of manner, fanny does indeed resist, and her aunt's sense of this impels her astounding attempt virtually to become fanny: depend upon it, it is not you that are wanted; depend upon it it is me (looking at the butler) but you are so very eager to put yourself forward. what should sir thomas want you for? it is me, baddeley, you mean; i am coming this moment. you mean me, baddeley, i am sure; sir thomas wants me, not miss price (p. , xxxii). for an appalling moment, her madness reveals itself not simply as a yearning for intimacy with sir thomas's power but as a desperate hunger for the identities of other people, even the most insignificant. but the contagion is wider spread. tom bertram's peevish com- plaint about mrs. norris- "it raises my spleen more than any thing, to have the pretence of being asked, of being given a choice, and at the same time addressed in such a way as to oblige one to do the very thing" (p. , xii)-reveals, as fanny sees, his will to have his own way, as when by extravagance he cheer- fully deprived edmund of half his income or tried to bully fanny into joining the company of lovers' vows ("let her choose for herself as well as the rest of us," edmund had then to urge him). lady bertram is in her own vegetable way quite as selfish as her sister and daughters; sir thomas sadly comes to see that he has spoiled his family not only by indulgence but by repressing their moral freedom; even edmund attempts to urge fanny into henry's arms. robbing people of their choice lies at the heart of virtually every significant incident in the novel. something disturbingly more than a lack of sincerity vitiates the charm of the crawfords. we notice that henry is attracted to fanny as to a puzzle: i do not quite know what to make of miss fanny. i (lo not under- stand her. i could not tell what she would be at yester(lay.... i must the difficult beauty of mansfield park try to get the better of this. her looks say, "i will not like you, i aim determined not to like you," and i say, she shall (p. , xxiv). lawrence would know what to make of this hunger for "knowing," this will to destroy another's separateness. henry is of course more than a lovelace, and his "moral taste" is sufficient to appreciate fanny's capacity for feeling, but the growth of his love gets consistent qualification: it would be something to be loved by such a girl, to excite the first ardours of her young, unsophisticated mind! (p. , xxiv). [his vanity] convinced him that he should be able in time to make [her] feelings what he wished.... [his love] made her affection appear of greater consequence, because it was withheld, and determined him to have the glory, as well as the felicity, of forcing her to love him (p. , xxxiii). his will to dominate, to recreate the world as an image of his wishes, keeps him from ever quite recognizing her reality as "an- other." nor is this a matter of the narrator imposing a commentary on henry that his speech and behavior won't support; when, for example, mary doubts that fanny would much appreciate their dissolute uncle, henry can airily reply that "he is a very good man, and has been more than a father to me. few fathers would have let me have my own way half so much. you must not prejudice fanny against him. i must have them love one another" (p. , xxx). it is not moral imperception-his tone suggests some amusement about both his uncle and himself-but his determination that both fanny and the admiral shall be objects to manipulate that defines the irony. mary is a richer figure, subject to more complex attention and concern, but she too shows a corruption by will. as in her dismis- sal of time and space at sotherton, she likes to imagine worlds more congenial than the real one. edmund's simple determination to be ordained seems to her (pp. - , xxiii) a deliberate insult, shattering her trust in a different, imaginary future: "it was plain now that he could have no serious views, no true attachment, by fixing himself in a situation which he must know she would never stoop to." she suffers from not being able to strike back at sir thomas, the presumed "destroyer" of her "agreeable fancies"- "not daring to relieve herself by a single attempt at throwing ridi- nineteenth-century fiction cule on his cause" (p. , xxv). as for any child, what others do has always direct reference to herself, as when she equates,.edmund's "adhering to his own notions" with "acting on them in defiance of' her" (p. , xxix). this wilfulness must, to be sure, be weighed against her appreciation of edmund himself (as well as her dream bf him as a "man of independent fortune"), and against her' ability to rebuke herself: "she was afraid she had used some strong-some contemptuous expressions in speaking of the clergy,' and that should not have been. it was ill-bred-it was wrong. she wished such words unsaid with all her heart" (p. , xxix). the dashes indicate the difficult' achievement of honesty, as she resists the tempting understatements of her fault. she engages mnore of our sympathetic interest than her brother, but mary, rather more gravely than emma woodhouse, is prey to what jane austen's revered dr. johnson called "the dangerous prevalence of imagina- tion." only fanny recognizes the perils of will, in resisting ednmund's advancement of henry as a fit object for her reforming powers: "i would not engage in such a charge," cried fanny, in a shrinking accent-"in such an office of high responsibility!" "as usual, believing yourself unequal to anything!-fancying every thing too much for you!" (p. , xxxv). edmund seldom appreciates subtlety; far from "fancyihng," fanny here recognizes both the difficulty and the impropriety of disturb- ing the existences of other people, however bad. she comes as close as she can to explaining this when henry seeks to draw her into intimacy by soliciting her advice: "when you give me your opinion, i always know what is right. your judgment is my rule of right." "oh, no!-do not say so. we have all a better guide in ourselves, if we would attend to it, than any other person can be" (p. ;, klii). the reader who thinks conscience a quaint concept is (as he de- serves to be) in trouble here. fanny's inner guide is her only defense against will, her own or someone else's. mansfield park, a novel without miracles, has no instance of one character converting another by sitting down for a good, serious talk. rather, those who have a conscience, like edmund and sir thomas. work out the difficult beauty of mansfield park their salvations in the quiet privacy of their own thoughts, while those who have none, like henry and mrs. norris, or who cannot find the privacy to listen to theirs, like mary and maria, find no refuge from the desolations that the will insists on. indeed, had jane austen wanted to continue the pattern of titles begun with sense and sensibility and pride and prejudice, she might have called mansfield park (inelegantly enough) conscience and consciousness. opposed to conscience, the inner guide, is "consciousness" in a common eighteenth-century sense: "having one's thoughts and attention unduly centred in one's own per- sonality; and hence, apt to imagine that one is the object of ob- servation by others; self-conscious." (c. s. lewis, who rejects this meaning as a semantic impossibility, offers another equally relevant-having a secret which you think someone shares-and admits that being in such a state may make you be and look "self- conscious.") in mansfield park, people are constantly watching one another, gauging their effect on their listeners, searching, as in a mirror, for signs of their own existence. the crawfords, if not the source of the infection, are at least the agents of its spread. when mary congratulates lady bertram upon the peace which, for bystanders, must follow the selection of lovers' vows, she re- marks: " 'i do sincerely give you joy, madam, as well as mrs. norris, and every body else who is in the same predicament,' glancing half fearfully, half slyly, beyond fanny to edmund" (p. , xv). such consciousness is usual in mary's conversation: "miss craw- ford turned her eye on [fanny], as if wanting to hear or see more, and then laughingly said, 'oh! yes, missed as every noisy evil is missed when it is taken away.... but i am not fishing; don't compliment me'" (p. , xxix). and even her letter-writing is tainted: to have such a fine young man cut off in the flower of his days, is most melancholy. poor sir thomas will feel it dreadfully. i really am quite agitated on the subject. fanny, fanny, i see you smile, and look cunning, but upon my honour, i never bribed a physician in my life (p. , xlv). for her, being conscious is a way of achieving relationship-she shares with others the amusing pretence of her wickedness and thus assures them that it is a pretence-and so of assimilating oed, "conscious," def. . c. s. lewis, studies in words (cambridge, ), p. . nineteenth-century fiction people to the needs of her will. that we are made to see it partly as a pathetic effort to escape isolation in the self is a tribute to the fairness and compassion with which jane austen presents mary. because less is at stake for him, henry's more assured conscious- ness can be drawn with a lighter touch. in the fine comedy of chapter xxxiv, his reading of shakespeare, his renouncing of ama- teur theatricals, and his discussion of preaching with edmund are all calculated for their effect on fanny, whom he keeps looking at and interrogating: ". . . nineteen times out of twenty i am thinking how such a prayer ought to be read, and longing to have it to read myself-did you speak?." stepping eagerly to fanny, and addressing her in a softened voice; and upon her saying, "no," he added, "are you sure you did not speak? i saw your lips move. i fancied that you might be going to tell me i ought to be more attentive, and not allow my thoughts to wander. are you not going to tell me so?" "no, indeed, you know your duty too well for me to-even supposing she stopt, felt herself getting into a puzzle, and could not be pre- vailed on to add another word (pp. - ). the strands of the theme come together. henry's will to compel her love, however comically softened, aims at incorporating her into'his performance-even to the extent of writing her lines for her-and her conscience, which again forbids her to dictate to anyonie, is touchingly endangered by the whisper of imagination ("even supposing"). henry watches fanny, edmund (unwittingly drawn into the mannerisms of conscious play) watches them both, and 'with jane austen we watch them all. but at the center henry watches not fanny but himself as her response reflects him, en- joying with some justice) his own performance for its sheer inven- tive gusto. and when he has finally got her alone: "do i astonish you?"-said he. "do you wonder? is there any thing in my present intreaty that you do not understand? i will explain to you instantly all that makes me urge you in this manner, all that gives me an interest in what you look and do, and excites my present curiosity" (p. ). but of course he can't explain, fully; involved is not simply his love as he would explain it, but a deeper self-love that can respond the difficult beauty of mansfield park to others only in proportion to their potential for becoming him- self, in effect, by becoming his creatures. mansfield park, with its clashes of will and consciousness, is in fact a world of children, most of them struggling not to grow up. henry has, preeminently, the child's fascination with the idea of changing his identity, as his delight in acting suggests. if edmund can make him yearn for the clerical life, william price, for a moment, arouses his hitherto unrecognized love of seafaring and honest toil (pp. - , xxiv). or lacking other stimulus, his protean interests can be absorbed by a game of "speculation," with an opportunity to manage other hands than his own (p. , xxv). but play is more than a relief from boredom. the planned performance of lovers' vows is wrong, i think, because it uses the theatrical blurring of art and life in the service of calculated dalli- ance. mary inquires: "what gentleman among you am i to have the pleasure of making love to?" (p. , xv), and as usual the joke is no joke at all for those who share her consciousness. both mr. trilling's idea about the moral dangers of "impersonation" and miss lascelles' remark that jane austen disapproves of "make- believe that is not acting" are pertinent. mary and henry use the play to approach closer to their objects, and those objects, maria consciously and edmund confusedly, understand this and accept it. they are not acting but disguising emotional reality in art; but in another sense the crawfords are always acting-life and art are for them not distinct, and to draw maria and edmund into their impersonations, for which the play is only a more or less acceptable public vehicle, is to threaten their living identities without exposing their own in return. that they all sense this appears in their response to sir thomas's surprise return, which jane austen describes as "consternation," "a moment of absolute horror." the terms are excessive only if measured by adult values, and these are not the ones that apply: ... after the first starts and exclamations, not a word was spoken for half a minute; each with an altered countenance was looking at some other, and almost each was feeling it a stroke the most unwelcome, n'iost ill-timed, most appalling! ... every other heart [except yates's and rushworth's] was sinking under some degree of self-condemnation or undefined alarm, every other heart was suggesting "what will become of lascelles, jane austen and her art, p. n. nineteenth-century fiction us? what is to be done now." it was a terrible pause.... jealousy and bitterness had been suspended; selfishness was lost in the common cause (p. , xix). this is more than idle mock-heroic fun; they respond like children who have been caught at some nasty, secret indulgence, and they know it and can only unite in their guilt. the horror is quite real and, from their viewpoint, quite justified, although they soon dis- cover that the adult view-sir thomas's-is more liberal than they had supposed. it is a crucial moment when sir thomas steps into his billiard room and finds himself on the stage of a theater, "opposed by a ranting young man, who appeared likely to knock him down backwards"; but adult equilibrium is equal to the threat, the stage comes quietly down, and art and life momentarily get sorted out. there is little charm in these children, whose dominant emo- tion seems to be malice. mary recommends henry to fanny by celebrating "the glory of fixing one who has been shot at by so many; of having it in one's power to pay off the debts of one's sex! oh, i am sure it is not in woman's nature to refuse such a triumph" (p. , xxxvi). one suspects she has been reading etherege, but the life she observed at the admiral's was fairly etheregean, and her relish in the idea of "paying off" someone recalls her thwarted wish to hit back at sir thomas. even cruder malice impels tom's and maria's "glee" at edmund's descent from "that moral eleva- tion" they have always resented, when he agrees to act in the play (p. , xvii), and in maria's struggle with julia for henry's atten- tions: maria felt her triumph, and pursued her purpose careless of julia; and julia could never see maria distinguished by henry crawford, without trusting that it would create jealousy, and bring a public disturbance at last. fanny saw and pitied much of this in julia; but there was no out- ward fellowship between them. julia made no communication, and fanny took no liberties. they were two solitary sufferers, or connected only by fanny's consciousness (p. , xvii). in this nursery-world of aggression and spite, only fanny has full consciousness in the better sense, sympathetic understanding of what others feel. she too is a child-witness her timid withdrawals the difficult beauty of mansfield park to her "nest of comforts" in the east room-but only in her (and to some extent, edmund) is childhood given its happier associa- tions of innocence and tender affection. but while fanny measures the profound moral disturbances in her companions, she is scarcely the monument of feckless virtue she has been taken to be. though she lacks irony, she has a streak of disconcerting common sense that has almost equal force, as in her mild remark that "let him have all the perfections in the world, i think it ought not to be set down as certain, that a man must be acceptable to every woman he may happen to like him- self" (p. , xxxv). nor is she sentimentally exempted from jane austen's ironic scrutiny," as her fondness for quoting scott warns us. we hear of her "feeling neglected, and ... struggling against discontent and envy" (p. , vii); we see her hardly able to suppress laughter when tom's rude remark about dr. grant is almost over- heard (p. , xii); we see her in the grip of abysmal self-pity for having excluded herself from the play (pp. - , xvii), where the proper response is not simple commiseration but a reflection that if she will insist on being good, she had better learn to valule virtue properly, by experiencing its cost. for all her affectionate concern for fanny, jane austen keeps her distance even in the later episodes, when fanny begins to growv up. most notably, we see her human limitations in her reactions to edmund and mary. "it was barbarous to be happy when ed- mund was suffering. yet some happiness must and would arise, from the very conviction, that he did suffer" (p. , xxviii). ed- mund's defense of mary provokes something close to venom: 'tis nonsense all. she loves nobody but herself and her brother. her friends leading her astray for years! she is quite as likely to have led them astray. they have all, perhaps, been corrupting one another (p. , xliv). she can quite unfairly attribute mary's renewed interest in ed- mund to his monetary prospects when tom seems near death- mary's motive is surely not simple greed but the feeling that being "i find that m. c. bradbrook has made this point, with a different set of quota- tions from mine, in "a note on fanny price," essays in criticism, v ( ), - ; but the irony shows miss bradbrook that "fanny is a goose, with more than a pliant disposition and light blue eyes in common with harriet smith." miss lascelles (jane austen and her art, pp. - ) points out that janle austen is usually amused by people who quote familiar literature. nineteenth-century fiction a clergyman's wife would be pleasant if one could cut a figure of style. after edmund gives mary up, fanny tells him of her interest in tom's dying-perfect delicacy might after all have spared mary this; and fanny's reaction to edmund's misery is decidedly mixed: she knew [he was suffering], and was sorry; but it was with a sorrow so founded on satisfaction, so tending to ease, and so much in harmony with every dearest sensation, that there are few who might not have been glad to exchange their greatest gaiety for it (p. , xlviii). this wry assessment, taken with the other revelations of her im- perfection, warns us not to love her too uncritically; she may be "my fanny" to jane austen, but the tone of indulgent affection confesses that there may be something in her to forgive. far from being unreasonably "protected" by the novelist, fanny is her most vulnerable heroine, and so her most human one. fanny's moral views win out, but not through any betrayal of the "life" the novel has rendered. the presentation of henry and mary consistently reveals the psychic weakness at the heart of their apparent vitality and strength, and virtually every incident under- lines their disastrous effect on people whose weakness is less talented and skilful. limited as it is, fanny's morality has after all a good deal to recommend it as mr. trilling makes eloquently clear); to condemn mansfield park because in it "the deadly sins are passion and infidelity" is to invoke a sophistication that, with suitable subtlety in defining "passion," would have puzzled or dismayed george eliot, james, tolstoy, or lawrence. but if we are chastened by fanny's simple virtue, we are by no means invited to embrace it as some triumphant moral imperative. jane austen's narrative detachment in the last chapter marks not loss of interest or embarrassment about mary and henry, but an un- derstanding that the union of fanny and edmund falls somewhat short of solving the universe. each, for the other, represents an accepted limit of achievement. fanny is what edmund's ironically conceived sobriety of virtue has deserved, and no more. edmund in fact seems the most convincing of jane austen's heroes-convincing because he is "placed" by the reservations we are consistently made to feel about him. both his reality and his limitations are finely secured by his account to fanny of his final interview with mary: mudrick, jane austen, p. . the difficult beauty of mansfield park she was astonished, exceedingly astonished-more than astonished. i saw her countenance change. she turned extremely red. i imagined i saw a mixture of many feelings-a great, though short struggle-half a wish of yielding to truths, half a sense of shame-but habit, habit carried it. she would have laughed if she could. it was a sort of laugh, as she an- swered, "a pretty good lecture upon my word. was it part of your last sermon? at this rate, you will soon reform every body at mansfield and thornton lacey...." she tried to speak carelessly, but she was not so careless as she wanted to appear.... i had gone a few steps, fanny, when i heard the door open be- hind me. "mr. bertram," said she, with a smile-but it was a smile ill- suited to the conversation that had passed, a saucy playful smile, seem- ing to invite, in order to subdue me; at least, it appeared so to me. i resisted; it was the impulse of the moment to resist, and still walked on. i have since-sometimes-for a moment-regretted that i did not go back; but i know i was right; and such has been the end of our ac- quaintance! (pp. - , xlvii). there is much here to respect. edmund tries to report honestly and fairly, to sort out truth from personal bias, and his hesitations prove his own mixed feelings. but it is his report, and we may as- sume that jane austen sees further. mary's "sort of laugh" is the final victory of consciousness over both conscience and any genuine feeling; we regret it, not simply because it must banish mary from the mansfield world, but, more deeply, because she almost under- stood the issue. her last smile even edmund saw as possibly am- biguous, and we may find it movingly so. is it saucy and impeni- tent, or is the nearest she can come to a gesture of apology and regret? is it, even, the neurotic's desperate plea to be understood and forgiven despite all his resistances? but if we ponder what might have been, for edmund the door must close forever; and we needn't scorn his inability to bear very much reality until we know we can ourselves. mary's complex troubled consciousness can have no place in the settled society of mansfield but this is a criticism of that society as well as of mary. we may trust jane austen to know that the price of peace is considerable simplification. the novelist's parting with henry is less successful. he is called "cold-blooded" in his vanity which accords oddly with the henry we have been made to see almost exuberantly enjoying his gifts; and jane austen seems unduly insistent about what he has missed: could he have been satisfied with the conquest of one amiable woman's affections, could he have found sufficient exultation in overcoming the nineteenth-century fiction reluctance, in working himself into the esteem and tenderness of fanny price, there would have been every probability of success and felicity for him.... would he have deserved more, there can be no doubt that more would have been obtained.... would he have persevered, and up- rightly, fanny must have been his reward-and a reward very voluntar- ily bestowed-within a reasonable period from edmund's marrying mary (p. , xlviii). the novel totters on the brink of a miracle. those nervous modi- fiers ("deserved more," "and uprightly") leave unsolved a problem about the henry we know. could he deserve more and yet remain henry crawford as the novel has defined him? his attraction to fanny stems from her resistance, from his need to prove the strength of his will by breaking hers; his seduction of (or by) maria is no failure in him or in the novelist, but the inevitable fulfilment of his compulsive need to dominate and his passion to change identities. children do grow up, and (less commonly) people do change their ways, but surely more than a fanny price is required to change a henry crawford so radically. for all jane austen's shrewdness about how people get married, the novel's moral design quivers for a moment. but the miracle of henry's redemption remains subjunctive, and i see no other flaw in mansfield park. the final withdrawal of the novelist from her created world, if it smacks a little of field- ing's excessively "healthy" scorn for those who believe in fiction, provides a necessary perspective on the mansfield society. edmund and fanny receive an affectionate but knowing farewell, in an idiom that mocks edmund's own fussy speech: even in the midst of his late infatuation, he had acknowledged fanny's mental superiority. what must be his sense of it now, therefore? she was of course only too good for him; but as nobody minds having what is too good for them, he was very steadily earnest in the pursuit of the blessing, and it was not possible that encouragement from her should be long wanting (p. , xlviii). like fanny, he will never quite know what he missed, and we must agree with the novelist that, on the whole, it is better that they don't. this is not to say that fanny and edmund are simply the butts of jane austen's dark comedy. she does, however, include them in the difficult beauty of mansfield park a larger field of irony that they never get out of, and thus the novel differs from her other mature works, where the heroes and heroines are either mostly exempt from irony (like mr. knightley or anne elliot), or win their release from it as the plot brings them to know what jane austen knows-or most of it-about life. fanny and edmund learn less, but that is the point; for once we are to con- sider how people who, like most people, have no superabundance of wit and charm and wisdom are to get along in the world. they get along, quite simply, by avoiding what they cannot understand, which in mansfield park is the struggle of tormented souls like mary and henry to define their own reality by denying reality to other people. jane austen does not forbid us to hope that integrity and liveliness of spirit may coexist in people, but she knows that when they clash, as they often will, the latter usually wins; if we are compelled to choose, mansfield park reluctantly admonishes us to opt for integrity. pride and prejudice and emma show amply jane austen's preference for the union of brilliance and con- science, but they show also that it may have to be achieved by virtually miraculous means, by those changes of heart that happen lamentably more often in novels than in life. in mansfield park, virtue is its own reward, and for once jane austen firmly insists that it may have to make do with itself. this meaning, if i am right in finding it, is no failure of the novelist's integrity but its triumph, and a prediction (as emma, for all its radiance, is not) of what fiction was to be for the masters of the next hundred years. mr. trilling, who plays with this same proverb, says that virtue gets more than itselt, because fanny grows up to be the virtual mistress of mansfield park. literally, of course, she becomes mistress of mansfield parsonage, and jane austen resists what must have been the sore temptation of killing tom to make her heroine rich; fanny gets, in effect, the life mary could not accept, and it seems pretty minimal when we think of what elizabeth bennet or emma or even anne elliot get. then too, there is edmund! article contents p. p. p. p. p. p. p. p. p. p. p. p. p. p. p. p. p. issue table of contents nineteenth-century fiction, vol. , no. (jun., ), pp. - front matter [pp. ] the ironic vision of emily brontë [pp. - ] billy budd and the limits of perception [pp. - ] desperate remedies and the victorian sensation novel [pp. - ] the difficult beauty of mansfield park [pp. - ] the theme of alienation in silas marner [pp. - ] the structure of the portrait of a lady [pp. - ] notes and reviews review: untitled [pp. - ] review: untitled [pp. - ] review: untitled [pp. - ] back matter [pp. ] wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ knowledge cultures ( ), pp. – , issn - , eissn - doi: . /kc a beautiful life as an end of education christoph teschers christoph.teschers@canterbury.ac.nz university of canterbury abstract. following the theme of a conference held in christchurch, new zealand in , this article explores the notion of “enabling students to live a beautiful life” as a possible end of education. a distinction is made between short-term, contextual aims in education and overarching, encompassing end(s) of education. following dewey, educational aims are considered to be manifold and to change over time within a socio- cultural context, whereas a proper end of education, if such a thing exists, could be seen as “the best possible realization of humanity as humanity.” drawing further on the work of r. s. peters, who contests the existence of any final end of education other than education itself, it can be seen that proposing such an end can be a challenging undertaking. nevertheless, this article argues for a possible humanistic end of education, building on schmid’s philosophical concept of the art of living in conjunction with the german notion of bildung and aristotle’s concept of phronesis, consolidating peter’s and dewey’s positions. an argument is made that a, if not the end of education would be to support every person as much as reasonably possible to develop their own art of living and live a good and beautiful life. resulting implications for schooling, curricula and education systems are explored to show how education understood in such way transcends theory into practice. keywords: aims and ends of education; good life; dewey; r. s. peters; wilhelm schmid exploring educational aims education, when discussed in both public and political forums today, is often approached with the question: what can education do for a country’s society and economy? from a society and community perspective, this question is important and cannot be ignored; however, it will be argued here that approaching education from this perspective alone is not enough and falls short to do justice to education and its role for human beings as individuals and members of society. therefore, following an argument presented by eckard liebau ( ), it is necessary to reverse this question and ask “what structure a society should have, to be capable and willing to provide for people’s educational demands” (p. , my translation, italics added). this inversion, liebau argues, raises a number of questions, including “the question of schooling: what does schooling contribute to education – and what can and should it contribute?” (p. , my translation). what is raised here are a number of issues regarding aims in and ends of education, beginning with the understanding of the term “education” itself. education can be understood as (i) knowledge, bildung (i.e. self-formation, cultivation and practical wisdom) and understanding that can be acquired, as (ii) the education process of teaching and learning, and it can refer to (iii) the education system as a whole, which will be termed schooling for the purpose of this article. what education, the education process, and schooling can and cannot do, and should and should not do, is certainly connected, as are their aims and ends. these can, however, also be quite different from each other. it will be argued that aims that are voiced in relation to either education, the education process, or schooling are further dependent on the perspective of the person or entity who is formulating these aims: these include, among others, the student, the teacher, the school, the parents, the local community, society as a whole, government officials and policy makers, and industry and economy representatives. although all these “stakeholders,” as people and bodies with an interest in education are often called in current neoliberal terminology (but which shall be avoided in the further discussion), have their own agendas and aims for a country’s education system, including the educational content that is deemed important, i will focus on the main agents with a traditional interest in educational processes and outcomes: students, teachers, and society – understood here as a community of individuals sharing resources and common interests. to start this contemplation, a short narrative will be presented to illustrate some traditional perspectives regarding education: set in a traditional culture of early settlement, imagine a number of young people sneaking away from the village one day to explore the neighbouring woods, when they stumble upon a small clearing where one of the tribe’s men is working on carving a bow. the boys know that he is the most skilled member of their village and every hunter wants to have a bow made by this bow-maker. initially captivated by the deliberate and careful process of shaping and making a bow, the boys stand and watch for a while. however, most lose interest after a while and take off to explore the woods further. one boy, however, is so fascinated by the process that he sits down and watches the bow-maker. occasionally, he might ask a question to understand what the man is doing and why. the boy finds himself to be so interested in the process of carving and making of bows, that he comes back the next day and the day after. on the third day, the boy brings with him a fresh hazelnut stick, as he learned that hazelnut wood is flexible and well suited for bow-making. the bow- maker, who is aware of the importance of his trade for the community and is genuinely interested in passing on his expertise to an interested youth, helps the boy with all the little steps that are needed to make his first bow. a number of important aspects for education and the process of education can be found in this short vignette, which could be considered as the beginning of an educational apprenticeship relationship. for once, we can see the educational triangle of student, teacher and topic; further, we can see that the well-being and continuation of the community play a role in the considerations of the bow-maker for teaching the boy. this emphasises the role of education for the survival and growth of the community. we also find a notion of specialisation and taking different tasks within a community for the benefit of all, which allows the bow- maker to carve bows but still be nourished and provided for by the rest of the tribe. from the student’s perspective, interest is a key theme in this narrative, as it supports the boy’s curiosity and he continues his observation when his friends move on. it also keeps him motivated over time to learn more and to try for himself. i would argue that, although societies are more complicated than portrayed in the rather simplistic setting of this short narrative, it still illustrates some of the key aspects that need to be considered in the context of aims in and ends of education: the interest and motivation of the teacher, of the student, and the matter at hand. in this article, the notions of ends and aims of education will be critically discussed and an argument be made that, although many aims exist, a potential end of education can be formulated, drawing on schmid’s ( ) concept of the art of living. some implications for schooling will be explored and a call be made to shift the focus of current education systems towards the development of a good and beautiful life for all children in their diversity and uniqueness. distinguishing educational aims and ends although often used synonymously in the public arena, a distinction shall be made here between aims in education and ends of education. as john dewey ( / ) wrote, aims in education are manifold and have to be negotiated by each generation anew. aims in education are, therefore, contextual and dependent on the historical, cultural, social and individual circumstances that are relevant for each educational setting. aims are understood here as achievable, measurable, relatively narrow in focus, contextual, and potentially subjective, depending on each agent’s perspective and role. therefore, it can be argued that any contemplation of aims in education, as understood here, refers to the above mentioned interpretation of the process of education, as in teaching and learning, or deliberate educational settings such as schooling. education in the meaning of having knowledge, bildung, understanding, prudence and practical wisdom cannot have aims per se, only end(s), as aims include deliberate intention which again requires a person or entity representing one or multiple persons (dewey, / , p. ). the aims of the bow-maker, for example, might be to pass on his knowledge and expertise for the good of the tribe, but also because he might be proud of his craft and wants to pass it on to the next generation. the aim of the tribe to allow the bow-maker to take the time for his work and to teach the young person is likely the benefit of good bows that support the survival of all. the student’s aim, so we can assume, is, beyond intrinsic motivation, to learn a craft that he is interested in and that gives him purpose and a place in the community. the matter at hand, the knowledge and skill to make bows does not have an aim of its own, but the end of supporting the hunters in their ability to provide game for the community. returning to dewey’s discussion of educational aims, he identifies three main areas that seem to encapsulate most aims people associate with education: (i) the natural, individual development as portrayed by rousseau; (ii) socialisation (or social efficiency); and (iii) personal mental enrichment or culture (p. ). as mentioned above, aims are also dependent on one’s viewpoint. a student engaging in educational processes might see education as a means to learn about something she is interested in, she might want to be able to get a job and make money, she might feel the desire to contribute to society in a meaningful way, or she just might want to get good grades to please – or not upset – her parents. a teacher might take pleasure in teaching young people, he might be passionate about his subject and others sharing his passion, he might want to see his students flourish, he might see teaching as an important contribution to the continuation and development of society, or all of the above; he might just want to get good performance reviews to have a secure job and make a living. students’ and teachers’ aims in education are, one could argue, personal and individual, often multiple aims existing in parallel, and, although often being similar within each group, they can potentially be quite different between these two participating groups of educational processes. aims of a more structural level are raised by society, mostly expressed through educational policies, rules and curricula on a school, state or national level. it is probably not unreasonable to say that aims proposed on behalf of a society are mostly intended to cater for the perceived well-being and good of this society as a whole. if this includes the well-being of each individual, the greatest good of the most, or the greatest good of the ruling class depends on the social, cultural and political structure present in each system; an aspect that will be revisited later on. following this brief reflection on aims in education, the question arises if there is or can be a single end of education, and if it would be the same for education, the education process, and schooling. ends of education are understood here as inherent to education (knowledge, bildung, understanding) and, by extension, the education process that leads to ‘having an education,’ being educated, and acquiring bildung. ends are seen here, in contrast to aims, as broad in scope, holistic, unspecific, and non-prescriptive. two notable educational theorists who contributed significantly to the discussion around possible ends of education are dewey ( / ), as mentioned above, and r. s. peters ( ). peters argues that there should not be a proclaimed final end of education, as any such end would bear the potential to be a dangerous undertaking, as terrible things have been done by passionate (and fanatic) advocates of final ends of education (pp. – ). peters argues against reducing education to be a means to an end and rather advocates for education to be an end in itself: “there is a quality of life embedded in the activities which constitute education, and ... ‘life’ must be for the sake of education, not education for life” (p. ). peters’ warning is an important one, as indeed any prescribed end of education external to education itself, even well- intentioned ends such as “self-realization, the greatest happiness of the greatest number” (p. ), or the idea of a social democratic citizen demotes education as a means and opens the door for “an instrumental way of looking” at education, which allows for a potentially restrictive and exclusive approach to schooling. the question that arises here is, if these mentioned “ends of education,” which peters also refers to as aims in places, are actually ends of education or rather structural aims proposed by society. one could argue that aims, as they are intentional and therefore formulated by persons, are by definition extrinsic to education; however, an end of education that emerges from the role that education plays for human beings, would be intrinsic and not reduce education as a means to an end but rather describe the intrinsic role and importance of education itself. reflecting on aristotle’s notion of eudaimonia in his nicomachean ethics, and his claim that human beings strive in all they do to achieve eudaimonia, which effectively makes all human activity a means to this end of serene happiness, but that this serene happiness serves no other end than itself, would indicate that education itself would contribute to eudaimonia as an end for human beings. similarly, peters ( ) indicates that education might have another intrinsic purpose than education for its own sake, when he argues that “there is a quality of life embedded in the activities which constitute education” (p. ). he acknowledges that engaging in education (not necessarily schooling) contributes to “a quality of life,” which could be understood as a contribution to eudaimonia. dewey ( / ), on the other hand, although similarly wary of the notion of a final end of education, does suggest “the promotion of the best possible realization of humanity as humanity” as a potential “proper end of education” (p. ). what distinguishes both of these potential ends of education from the earlier formulations of aims on a personal and structural level are (i) a broadness that does not promote one way of living or thinking above another, and (ii) that both seem to emerge from education rather than being prescribed externally as something that education should cater for. however, where these two ends differ from each other is the point of reference: peters’ notion of a “quality of life” refers to an individual engaged in education and adding this quality to his or her life; dewey’s formulation of a proper end aims towards a structural end of the perfection, “the best possible realization of humanity.” in the next section, i will explore if and how these two different positions could be consolidated towards a single end of education, which then should, as is argued in the final section, guide the aims we formulate for schooling and education systems today. consolidating dewey’s and peters’ notions of ends in education through the german notion of bildung in this section, an attempt will be made to consolidate the two different positions for potential ends of education as discussed above. to do this, a short excursus will be taken here to explore the german notion of bildung as a key aspect of education as it is understood in the german tradition. bildung, which is often translated as self-formation or self-cultivation, includes the aspects of knowledge, understanding, prudence and practical wisdom. it is understood as a formation of one’s self through knowledge and understanding of the world, as much as this is possible, to develop prudence and practical wisdom. however, to be able to gain a certain understanding of the world we are living in and the workings of it, the knowledge necessary to achieve bildung, needs to be broad and holistic. this understanding of education as bildung impacts therefore on schooling and curriculum content. a person who has bildung is considered a person of broad general knowledge, displaying prudence and practical wisdom, but also being well versed in aspects of human culture and aesthetics (liebau, ). to gain some understanding of human beings and their experienced life-reality in the world, one needs to have some insights into human culture and its expression in art, music, literature and philosophy. therefore, a curriculum that focuses mainly on reading, writing, maths and the stem subjects falls short of providing bildung. it might provide the necessary skills for contributing to a society’s industry and economy, although this can be questioned in a time where technical hands-on jobs are in decline and jobs in development, service and management are on the rise. the latter often require certain knowledge and understanding of human beings, social interactions, as well as critical, caring and creative thinking, learning often associated with humanities and social sciences. it is a holistic understanding of education that is represented in the german notion of bildung, which is essential for the german understanding of pedagogy and schooling (liebau, ). according to liebau, the notion of bildung has its origin in the period of german idealism and has strongly been influenced by wilhelm von humbuld at the end of the th, beginning of the th century, who connected scientific and humanistic approaches to understanding the world with the notion of aesthetics. hence, the strong links between bildung and art, music and drama, and the common translation of bildung as “self-cultivation.” it also includes the assumption of bildung being a life-long process of each individual to pursue one’s own perfection as a human being. to relate back to the two proposed aspects of ends of education suggested by peters and dewey, the tradition of the german bildung’s idealism can bridge this gap, i would argue, as german idealists proclaimed that the perfection of humanity, or the “best possible realization of humanity as humanity,” to use dewey’s words, can only be achieved through the perfection of each individual human being through bildung. therefore, allowing and supporting all individuals to pursue bildung, to develop their potential as human beings, and to partake in the “quality of life embedded in the activities which constitute education” (peters, , p. ) on an individual level, supports, i would argue, dewey’s proposed “proper end of education” of the “best possible realization of humanity as humanity.” a beautiful life as an end of education having argued how dewey’s and peters’ notions of potential ends of education can be consolidated through an understanding of education built on the german notion of bildung, an end of education will be formulated in this section that, i would argue, includes the personal and social perspectives as discussed above, as well as keeps in mind the concerns raised by peters. to do this, schmid’s ( ) philosophical concept of the art of living will be introduced here, which builds strongly on the notion of bildung and provides an understanding of what is important to be able to develop one’s own art of living and to live a good and beautiful life. this will be argued for as one end, and maybe even the end of education. it needs to be noted here that the line of argument presented here will be succinct as this point has been made before (teschers, ); however, it is necessary to reiterate the key points for the following argument in this article. wilhelm schmid ( ) is a contemporary german philosopher who has undertaken significant work towards a philosophical approach to the art of living. he advocates not for a fixed prescription of what a good and beautiful life looks like, but discusses the aspects relevant for the development of each individual’s own art of living. to engage in and develop one’s own art of living means, for schmid, to take up responsibility for one’s own life and to try to make it a beautiful life (schmid, ; teschers, ). the notion of a “beautiful life” is chosen deliberately by schmid, as a “good life” has a number of existing and potentially conflicting and misleading normative interpretations, such as being financially well off, living a life of pleasures, or living a morally good life. a beautiful life, however, is a question of individual taste and cannot be prescribed; just as a painting or another work of art is judged as beautiful or ugly based on each individual’s personal taste. similarly, schmid has chosen the notion of a “beautiful life” to emphasise that the art of living acknowledges that each individual has his or her own view on what it means to live a beautiful life. in this way, schmid’s concept of the art of living takes an individualistic approach in which each person actively shapes his or her own life according to what he or she considers to be beautiful. it is important to emphasise this individualistic approach towards judging a life to be beautiful, as any prescription of how one ought to live to have a beautiful life will be exclusive and falls short to include the diversity of the perceptions human beings might have on living a beautiful life. this point is also key in response to peters’ cautioning notion of prescribed ends of education, and similar criticism would apply for any prescriptive notion of a good and beautiful life. for schmid, each individual engaging in the art of living becomes an artist who is shaping his or her own life as a work of art. this, however, does not mean that all reins are off and one can do whatever one likes. schmid acknowledges that human beings generally live in communities and societies and are subject to ethical and moral implications. therefore, he developed, based on the aristotelian notion of phronésis (prudence and practical wisdom), an ethics of the art of living that is based on the self-interest of each individual, which through practical wisdom is transformed into a form of enlightened self-interest in which the individual pursuing the art of living will recognise that it is in his or her own best interest to create an environment that is conducive to living one’s own beautiful life. this environment, schmid argues, includes that each person is supportive of other people’s own version of living a beautiful life. therefore, each individual engaged in the art of living should be considerate and supportive of the development of other people’s art of living, which includes to respect personal boundaries and to abide by reasonable rules set by society (schmid, ; teschers, ). schmid’s definition of the art of living is also an active one. “to take up responsibility for one’s own life” means to be active, to take charge of one’s own life and the direction one takes in life, instead of being driven by external circumstances (parents, peers, culture, society, etc.). for schmid, the notion of (self-)reflection is important in this concept, as he argues that only a deliberate reflection and contemplation of the norms, values and beliefs one holds and is presented with by others (e.g. family, peers, culture, religion, society) allows the individual to consciously subscribe to certain norms, values and beliefs, instead of unconsciously adopting these in an unreflected manner. through this active element of reflection and deliberate acceptance or rejection of norms and values one takes charge of those defining aspects of one’s life that lead us to choose certain actions above others and to shape our self and our lives accordingly. the final aspect reflected in the short definition provided above is the aspect of “trying.” for schmid, engaging in the art of living does not automatically mean to succeed in having a beautiful life, but trying to shape one’s life towards what one would consider a beautiful life to be. this includes the idea of incompleteness; an unending strive towards a beautiful life which only ends with one’s final breath. indeed, for schmid ( a) the final argument or reason why human beings would engage in the art of living and would try to live good and beautiful lives would be the finality of life itself, which urges us to progress rather than to stay idle. it has been argued elsewhere (teschers, ) that education plays a relevant role for the development of a student’s own art of living: through teaching and the development of relevant skills, such as critical, creative and caring thinking, (self-) reflection, as well as bildung, the acquisition of relevant knowledge and the ability to “life-long learning.” schmid outlines a number of curriculum areas that are relevant for a person’s life-cycle and therefore important for the development of an art of living and a beautiful life: the human being as individual; the social human being; difficulties and burdens of human life; striving for fulfilment and meaning in life; religions, beliefs and cultures of humanity; and the personal shape of one’s life and global perspectives. although it can be contested that these areas encompass all relevant aspects of a person’s life-cycle, it seems intuitive that all these areas are relevant for people’s lives today. schmid’s concept of the art of living and education are therefore connected through education being able to support the development of students’ own art of living. however, i have argued elsewhere (teschers, ) that both also have a similar, if not the same end: to support human beings to live the best possible (most beautiful) life under the circumstances they are living in. hence, the strive for a good and beautiful life connects with aristotle’s notion of eudaimonia in so far as both are an end in themselves, and education, i would argue, is both, a means to the end of living a beautiful life, but also, for many, a necessary component of a beautiful life and therefore an end in itself, as argued for by peters. combing now peters’ notion of education as personal enrichment and dewey’s notion of the best possible realisation of humanity as humanity with the notion of bildung and schmid’s notion of the art of living, it can be argued that a proper end of education (including the process of education) would be to support all human beings to life the most beautiful life possible under the circumstances they are living in (see also teschers, ). consequences for schooling having formulated a possible end of education and as education and schooling needs to be considered distinctly, as argued above, it is necessary to explore which consequences this end of education might have on a country’s education system and curriculum. to start with, i would argue that it is fair to say that a country’s schooling system is led by the norms and values of this country’s society, ideally represented through the country’s government and leadership. for the sake of the argument at hand, i will assume that a country’s leadership aims to fairly represent the norms and values of the people they serve, leaving out oppressive and non-representative systems. as societies are made of people, it would further be fair to assume that the norms and values shared as a society represent the key norms and values of (the majority) of the members of this society. if we follow aristotle’s argument that each human being strives for eudaimonia (serene happiness), one could assume that the norms and values held by each individual, if they are consciously reflected and not just adopted, are believed to support a life that is supposed to leads towards eudaimonia. the difficulty we face here is people’s differing ideas of what leads towards a happy and content life. to complicate matters, psychologists have shown that people are generally not very good at predicting what actions and directions in life will lead to a happier and more content life (schwartz, ; seligman, ). from a philosophical perspective, we are also faced with the issue what “happiness” actually means and if what psychologists measure represents a notion of happiness that is similar to aristotle’s idea of eudaimonia. a response to these challenges can be found in schmid’s concept of the art of living. as has been discussed above, schmid’s art of living concept acknowledges an individual’s question of taste in regard to living a beautiful life. it does not prescribe norms, values and how one ought to live, but allows for each individual to reflect on their own norms, values and to take a direction in life that they consider to lead towards a beautiful, perhaps eudemonic life. what follows for a country’s education system is that, to represent all members of society, it should support not only a narrow prescribed way of living that a majority might agree on as potentially being a good life, but to support diversity in life-concepts beyond what would be considered ‘the norm’ within a society. the challenge for a society and their representatives, however, is to create a system that is holistically inclusive and feasible, while balancing people’s personal desire to strive for eudaimonia and to endure a continuation of provisioning a society with necessary resources through industry and economy. one could argue that many countries, especially those in which a neo-liberal ideology takes precedence (e.g. roberts, ), have focused more on the latter and the idea of supporting people’s happiness has been swallowed by the ideology that for people to have a good life what we need in a country is economic growth. however, it has been shown that on a personal level more money, items and amenities beyond a certain, relatively modest point, does not increase a person’s subjective well-being and enduring happiness in life (csikszentmihalyi, ; seligman, ). the mantra of more wealth equals happy people can therefore not be maintained. this then relates back to liebau’s inversion of the question of what education can do for society towards the question of what society can do for the educational needs of its members to enable them to live good and beautiful lives. what follows from these contemplations is that the inherent end of education to support all human beings to live the most beautiful life possible can be transferred into an overarching aim for schooling and a country’s education system, assuming that it is a commonly held value of a society to support its members to develop their own art of living and try to live a beautiful life based on their individually reflected norms and values and the implications of an ethics of the art of living as discussed by schmid. hence, what is argued for here is a re-focus on the humanistic aspects of education in addition to subjects and content areas that are important to find employment and become an active member of society. not to forget the knowledge and understanding necessary for active democratic citizens in democratic societies (dewey, / ). to provide some concrete examples of implications for schooling, it is suggested here that school curricula are reviewed to incorporate more readily content areas that are relevant for the development of students’ own art of living, such as the areas presented by schmid above: the human being as individual; the social human being; difficulties and burdens of human life; striving for fulfilment and meaning in life; religions, beliefs and cultures of humanity; and the personal shape of one’s life and global perspectives. in addition, some of the skills and faculties important for developing an art of living are critical self-reflection; critical, creative, and caring thinking; the development of practical wisdom; and an understanding of hermeneutical processes (teschers, , ). to incorporate all of these in meaningful ways in school curricula and teaching and learning would, it is argued here, support students more strongly to develop their own art of living, reflect on their own norms, values and beliefs, and to make prudent and reflected decisions. conclusion this article has explored some of the common meanings of the term ‘education’ in the public and academic arena, it has highlighted that it is important to distinguish between these meanings for the discussion of aims and ends in education and an argument has been made that an intrinsic end of education would be to support the development of people’s own art of living and ability to live their own beautiful lives. it has been further argued that, under assumption of aristotle’s claim that human beings generally strive for eudaimonia (serene happiness), it is a government’s responsibility, as representatives of the people, to develop an education system and curriculum that supports this strive and allows for the diversity of the direction people might take (within reasonable constrains to ensure the peaceful continuation of society). this does not suggest abandonment of subjects and content areas that are important to be a successful member of a country’s economy and industry, but to shift the focus again towards a more humanistic education that supports both: the necessity to work and move successfully within a society, and to gain the relevant knowledge and skills that are important for each person to develop their own art of living, to become the artists of their own lives, and to potentially shape these lives into beautiful works of art. references aristotle (n.d./ ). the nicomachean ethics. london, england: wordsworth editions limited. csikszentmihalyi, m. ( ). flow: the psychology of optimal experience. [modern classics edn.]. new york, ny: harper perennial. dewey, j. ( / ). democracy and education. hazleton, pa: the pennsylvania state university. liebau, e. ( ). erfahrung und verantwortung. werteerziehung als pädagogik der teilhabe. [experience and responsibility. values-education as a pedagogy of participation.] weinheim; münchen, germany: juventaverlag. peters, r. s. ( ). authority, responsibility and education. new york, ny: paul s. eriksson. roberts, p. ( ). neo-liberalism, knowledge and inclusiveness. policy futures in education, ( ), – . schmid, w. ( ). philosophie der lebenskunst: eine grundlegung. [philosophy of the art of living: a foundation.] frankfurt, germany: suhrkamp. schwartz, b. ( ). the paradox of choice: why more is less. new york, ny: ecco. seligman, m. e. p. ( ). authentic happiness: using the new positive psychology to realise your potential for lasting fulfillment. london, england: nicholas brealey publishing. teschers, c. ( , - december ). “lebenskunst” schmid’s concept of the art of living. annual philosophy of education society of australasia conference. (online proceedings). perth, australia: pesa. retrieved from https://pesa.org.au/images/papers/ -papers/pesa- -paper- .pdf teschers, c. ( ). an educational approach to the art of living. knowledge cultures, ( ), – . teschers, c. ( ). education and schmid’s art of living: philosophical, psychological and educational perspectives on living a good life. london, england: routledge. christoph teschers is faculty member at the college of education, health and human development, university of canterbury, new zealand. he has published several articles and book chapters and is author of education and schmid’s art of living ( ). taking an interdisciplinary approach, he is mainly interested in the relationship between people’s wellbeing, the philosophical notion of the art of living and educational theory and practice. other areas of interest include philosophy for children, positive psychology, inclusive education, ethics and social justice. a beautiful metaphor: transformative learning theory peter howie professor richard bagnall education and professional studies griffith university + peter.howie@griffithuni.edu.au corresponding author – peter howie june mailto:peter@moreno.com.au bio notes. peter c howie is a phd candidate with griffith university, australia, . his research is into the psychodramatic concept of warm-up and he is reconceptualising and evaluating the concept and developing a process for evaluating the goodness of a concept. richard g bagnall is professor in the arts, education and law academic group, griffith university, australia. his work is in the social philosophy of adult and lifelong education and he has published over books and papers in that field. a beautiful metaphor: transformative learning theory abstract this article presents a critique of both transformative learning theory and critical comments on it to date. it argues that transformative learning theory remains substantively the same as its initial exposition, in spite of a raft of problematic contentions voiced against it. the theory is argued here to be conceptually problematic, except at the level of a conceptual metaphor, which latter renders its many inconsistencies inconsequential, and which explains, not just its continued popularity among educational practitioners, but also its largely being ignored as a subject worthy of serious critique. introduction mezirow’s transformative learning theory is noteworthy to the extent that, over the last years, it has proven to have great staying power as an idea, and to be a prolific producer of offshoots and closely related ideas, while remaining true to its original construction (mezirow, , ; mezirow and associates, ). what is apparently anomalous about that historical progression, is that it has occurred in spite of many clear and unattended problems with the theory having been highlighted on numerous occasions. this paper seeks to provide a consolidated critique of the theory, drawing on those previously articulated problems, and to argue that the theory’s interpretation as a conceptual metaphor serves to explain the apparent anomaly. transformative learning theory (throughout this paper, transformative learning theory or the theory) was developed and first presented by mezirow and marsick in (mezirow and marsick, ). a collaboration between jack mezirow, victoria marsick, and others gave birth to the theory, then called perspective transformation, about which mezirow has written so extensively that it has become ‘his’ theory. however, it continues as a large-scale collaboration with many practitioners contributing through descriptions of their applications of the theory, and their understandings of it (mezirow, ; mezirow and associates, ; mezirow, taylor, and associates, ; taylor, cranton and associates, ). if one considers the number of people utilising the theory in one form or another, for activities such as research and designing learning interventions, it is reasonable to conclude that it continues to remain highly relevant for adult educators (taylor, , a, ). indeed, it has been celebrated as being the ‘new andragogy and as the central adult learning theory of the day by some transformative learning theorists (cranton and taylor, , p. ; taylor, ). this paper presents an outline of the theory, followed by an overview of critical evaluation of it to date. then follows an outline of the technical nature of conceptual metaphors and of why the theory can best be understood as a conceptual metaphor. the problematic areas of the theory that provide evidence for such an interpretation are then used as arguments for it. some implications of viewing the theory as a metaphor are then drawn out, before presenting some concluding comments. transformative learning theory transformative learning theory has a number of elements. it begins with a person andragogy (sometimes spelt ‘androgogy’) is a term that refers to principles of learning focused on adults. it is contrasted with the term ‘pedagogy’, which is focused on children’s learning. it was coined by knowles ( ) to emphasise the point that there might be different principles for teaching adults, rather than children. being engaged in activities that cause a disorienting dilemma leading them to modify or shift one of their meaning schemas or meaning perspectives, which are part of their frame of reference (mezirow, ). the shift may be fast or epochal, or it may be slow or incremental. it may be in the instrumental domain of learning or in the communicative domain of learning. it has an unsteadying influence on the individual’s life, with the consequence that the subject seeks to make sense of their experiences. this process is improved by the subject engaging both in their own critical reflection, and with other adults in rational discourse on the area that has shifted. these key terms are explicated below. the theory describes an adult’s assumptions, beliefs, and expectations about the world, as part of a frame of reference through which individuals filter their incoming sense impressions of the world. a person’s frame of reference, according to mezirow ( , p. ): ...selectively shapes and delimits perception, cognition, feelings and disposition, by predisposing our intentions, expectations, and purposes. it provides the context for making meaning within which we choose what and how a sensory experience is to be construed and/or appropriated. in that context, according to mezirow ( , p. , mezirow’s italics): transformative learning may be defined as learning that transforms problematic frames of reference to make them more inclusive, discriminating, reflective, open, and emotionally able to change. after a transformation in a frame of reference, a person is said to view themselves and their world in a superior manner to that previously, as a result of their assumptions italics here identify uses common in transformative learning theory writing. and expectations having been challenged and modified to better fit their reality or context. transformative learning is seen as a particular type of adult learning (mezirow & marsick, ; mezirow, , , ). two further structures are part of a frame of reference: meaning schemas and meaning perspectives (mezirow, ). a meaning schema is said to be constructed of beliefs about how something works, how to do something, how to understand something, someone or a group, or how to understand oneself. a meaning perspective is a more fundamental belief than a meaning schema and is, according to mezirow ( , p. ), a ‘structure of assumptions within which one’s past experience assimilates and transforms new experience’. meaning perspective beliefs might include, for example, a notion of a person’s legitimate role in the world, the importance of family, or a person’s identity. the possibility of transformation in either of these two structures is recognised, although transforming a meaning perspective may be seen as being more far reaching (mezirow, ). interpreting habermas’s ideas, mezirow ( ) developed the concept of domains of learning, and the theory now describes transformations in meaning perspectives as occurring in either the instrumental domain or the communicative domain. the instrumental domain is seen as involving an understanding of how things work, with meaning being created using hypothetico-deductive reasoning and experimental engagement with the environment (mezirow, , ). the communicative domain is seen as involving relationships between people: how people communicate together; how they present themselves; how they understand one another; and generally how beliefs and practises of human communication occur. it is where meaning is created through abductive reasoning, which is seen as the process of using one’s own experience to understand another’s, and where each step in the chain of reasoning suggests the next step (mezirow, ). the theory suggests that there are two types of transformation in meaning perspective: epochal and incremental (mezirow, ). an epochal transformation is said to occur when a learner’s meaning perspective shifts very quickly. an incremental transformation, on the other hand, is the result of small shifts in a meaning schema that, over time, perhaps over months or years, lead a learner to slowly realise that a meaning perspective has shifted. according to the theory, disorienting dilemmas, critical reflection, and rational discourse are experiences that can bring about transformative learning, with the application or experiencing of one or some combination of these elements leading to transformative learning. transformative learning may occur in a linear manner, or it may be disjointed, individualistic, fluid, or recursive (mezirow, ; taylor, , a, p. ). a disorienting dilemma is said to be a dilemma that causes a significant level of disruption or disturbance in a person, and where their frame of reference is shown to be inadequate to explain what they have seen, heard, or experienced. critical reflection is said to be a process whereby a person intentionally construes new meanings as a result of examining their own beliefs. it is presented as a process that can occur in many different ways. the theory describes three main frames for critical reflection (mezirow, , ): content reflection, where the data content is considered more deeply for its veracity; process reflection, where the systems that produced the data are held up to scrutiny; and premise reflection, which is reflection on underlying premises, beliefs, and assumptions. rational discourse is presented in the theory as a form of discussion with other people, focusing on personally and socially held beliefs and assumptions, and conducted in a logical and objective manner, to highlight any incongruencies, biases, or blind spots in those beliefs and assumptions, thus allowing them to be addressed. based on patterns of activities or behaviour that the participants in mezirow’s (marsick & mezirow, ) original study reportedly went through and related, there are recognised steps in the transformative learning process (marsick & mezirow, ; mezirow, , ): a disorienting dilemma; self-examination, with feelings of fear, anger, guilt or shame; a critical assessment of assumptions; recognition that one’s discontent and the process of transformation are shared; exploration of options for new roles, relationships, and actions; planning a course of action; acquiring knowledge and skills for implementing one’s plan; provisional trying of new roles; building competence and self-confidence in new roles and relationships; and a reintegration into one’s life on the basis of conditions dictated by one’s new perspectives. these ten steps were set out in the original explication of the theory and have changed little since. the beginnings of the theory are arguably in mezirow’s ( , p. ) argument for using grounded theory in ‘the systematic construction of an evolving and integrated body of inductively formulated generalizations by which the behaviour of adults in educational situations may be understood and predicted’, and in his notion of perspectives as ‘...people’s actions and statements of the ideas that go with these actions’ (mezirow, , p. ). the theory then emerged as perspective transformation, with mezirow ( , p. ) also suggesting that it was part of an ‘emerging transformation theory’, developed by using a grounded theory methodology. mezirow was thus the main initial developer of the theory. he suggested that the recognition of perspective transformation, combined with self- directedness, formed ‘the essential elements of a comprehensive theory of adult learning and education’ (mezirow, , p. ). he further developed his own interpretations of habermas’s ideas (mezirow, ) in his fostering critical reflection in adulthood (mezirow, ), culminating in his book on transformative learning, where the theory had its first full explication (mezirow, ). there he noted that those who can name ‘what is’ (p. ) in new ways, and can influence others to follow that naming, acquire power, or in this case influence. the initial explication of the theory arguably named ‘what is’ for a variety of educationalists, which for many has become the main adult learning theory of the day, allowing the investigation of new relationships, questions, and things to study (cranton and taylor, ). critical evaluation of the theory to date published critiques of the theory from different perspectives have appeared from the time of its initial articulation. there have been four main types of critical response to the theory. criticisms of the first type do not cast doubt on the veracity of the theory, but rather suggests that there are certain elements lacking, or requiring further elucidation, in order to improve it. such criticisms argue that the theory is ‘good’ and would be ‘better’, if the points of concern were adequately accounted for. criticisms of how the theory has dealt with context, relationships and affect may be fitted into this group (baumgartner, ; cranton and taylor ; taylor, , , ). while these criticisms have in fact contributed to the removal of some of the theory’s minor deficiencies, extending its intellectual reach, they cannot be considered criticisms of the fundamentals of the theory in any substantive manner. within this type of criticism is taylor and cranton’s perception of a lack of fundamental research into the theory’s underpinnings (cranton and taylor, ; taylor, , , ). in that vein, taylor ( ) cautioned that, because there might be as yet undetermined possible inadequacies in the theory, its application might lead to flawed conclusions. criticisms of the second type are those that can be considered ‘chicken or egg’ arguments: arguments that suffer from a circular causality dilemma, in which it is futile to argue whether one event comes before another. included here are the criticisms of collard and law, who saw the theory as lacking a coherent, comprehensive theory of social change (collard and law, , p. ), a point which is implicitly supported by others, such as clark and wilson ( ), and inglis ( , ). also in this category is merriam’s ( ) suggestion that a person must have a high enough level of cognitive functioning to engage in rational discourse and to critically reflect on, or otherwise engage in, transformative learning, and collard and law’s ( ) contention that ideal critical reflection is never really possible because of contingent variables, and that the theory is thus deficient. against that point, mezirow ( , ) suggested that critical reflection varies (depending on contingent variables), is never ideal, but can, nonetheless, contribute to transformative learning. in this case, mezirow, and collard and law, are falling into the circular causality trap. criticisms of the third type are those that involve a rejection of the theory from a conflicting philosophical standpoint. in this category, pietrykowski ( ) and clark and wilson ( ) have argued that mezirow’s theory of transformative learning is too modernist and emancipationist. given that mezirow has a stated orientation as an emancipationist, the argument then becomes an argument for-or- against an emancipationist viewpoint, and is a difference of philosophical standpoints, rather than a coming to terms with the substance of the theory itself (mezirow, ). another example here is collard and law’s ( ) and hart’s ( ) criticism of the theory on the grounds of its lacking a well-developed and explicit concept of power. newman ( ) was critical of transformative learning for a variety of reasons, which fall into this final grouping. the arguments presented are well crafted but we would argue that newman’s developed points do not go far enough. newman’s principal argument is that, what is described as transformative learning is really just good learning, any opposition to which is essentially a substantive philosophical matter. rather than a rejection of the theory as not adding anything to learning, the argument of this paper is that the theory is better understood as a conceptual metaphor. newman’s arguments do, though, point to serious questions about how the adult education community has taken the theory to heart and given it such prominence, when, from the examination of literature undertaken for this analysis, it is arguably inadequately theorized, a quality which, in itself, contributes to the reification of the theory to the level of a universal truth. criticisms of the fourth type are those that, while engaging with different aspects or applications of the theory, make small but consequential criticisms that call into question an element of the theory. they appear often as asides to the main argument, for example, that brookfield ( ) in his comment on the potential meaninglessness of the word transformative, and that of kokkos ( ) in his pointing out the possible divergence of academic views of the theory’s ‘components and its methods’ as part of another argument. such points are rarely picked up in subsequent articles, but are often telling, and they have importantly informed the critique developed in this paper. transformative learning theory as a conceptual metaphor transformation and learning, in colloquial terms, have what can be considered as overlapping meanings. thus, learning can be seen to have a transformative effect on the learner, and on the learner’s life and, likewise, transformation can be said to create, amongst other effects, learning. because of this, ‘transformative’ can be mistakenly seen in this context as merely an adjective, used to describe a particular type of learning. transformative learning however, the most popular cognate form of transformative learning theory, can also be seen as a conceptual metaphor, as a figure of speech connecting different conceptual domains (lakoff, ; morgan, ). transformation, as used by mezirow (marsick & mezirow, ; mezirow, , ), is the conceptual domain of consciousness raising, improving, becoming free from the past, undoing twisted views of the world, raising above self-limitations, being future oriented, becoming enlightened, unfolding spiritually, metaphorically of butterflies emerging, and all this through an inner awakening, creating a stirring of discontent that generates a drive in a person to enlarge their understanding and appreciation of life. in this domain, a person’s way of seeing the world can become more ‘inclusive, discriminating, reflective, open, and emotionally able to change’ (mezirow, , author’s italics). transformation implies nothing less than ‘light on the road to damascus’, a conversion, a recalibration, and re-integration with the world. transformation, brookfield ( , p. ) writes, is one of the most powerful words in the english language. it is not a mere adjective as it is used in this context. learning, on the other hand, is seen as the conceptual domain concerned with the acquisition of skills, knowledge and understanding brought about through a variety of processes, including reading, studying, being taught, teaching others, curriculum development, pedagogy, different ways of taking in, interacting, constructing, and assimilating knowledge, improving one’s understanding of that knowledge, and social and community advancement through such processes. while learning is, perhaps justifiably, reified, it also contains the mundane, the hard work, the tedium, the assessments, the arguments, the measuring of self against others, the failures as well as the successes. it is quotidian. mezirow (mezirow & marsick, , p. ) noted the irony that the re-entry programs he studied, and from which the theory emerged, had ‘transformed the perspectives of hundreds of thousands of women’ through consciousness raising classes, yet had never found their way into the literature of adult education. bringing transformation and learning together created a conceptual framework through the conceptual metaphor of transformative learning that arguably began this process of bringing legitimacy to consciousness-raising in adult education. mezirow (mezirow & marsick, , p. ) proposed that the objective of adult education should be fostering movement ‘toward a higher level of development on a maturity gradient’ through transformative learning experiences that help adults look at the sources of their needs and hence develop behaviour based on the new maturity, rather than focusing on behaviour change from only learning new behaviour on its own. according to lakoff and johnson ( , p. , author’s italics) ‘the essence of metaphor is understanding and experiencing one kind of thing or experience in terms of another.’ a conceptual metaphor is thus defined as one where a target conceptual domain, is overlain with a source conceptual domain (kövecses, ; lakoff & johnson, ). kovecses ( , p. ) wrote that a conceptual domain is any coherent organisation of experience. faulconnier and turner ( ) suggested that a conceptual metaphor is a conceptual integration created by blending ideas into a blended mental space that leads to new emergent meanings not contained in the original inputs. lakoff and johnson ( , p. ) suggested that our conventional ways of talking about arguments presuppose a metaphor we are hardly ever conscious of. metaphors are one way that our experience is made more coherent, and according to lakoff and johnson ( , p. ) a well-framed or novel metaphor has the power of defining reality, which is similar to mezirow’s ( , p. ) contention that naming creates reality. lakoff and johnson (p. ) went further in suggesting that conceptual metaphors may be the only way to organize and make coherent certain aspects of our experience that then can create realities for us, which themselves can play a part in constituting a license for policy change and political and economic action. arguably, transformative learning as a conceptual metaphor has done this. in this paper, we are arguing that transformation constitutes a specific source domain, which then influences, colours and creates new understandings in the target domain, in this case the domain of learning. lakoff and johnson ( , p. ) argued that metaphorical structuring in conceptual metaphors is only ever partial and not total. if it were total, one concept would be the other, rather than merely understood in terms of it. this is an interpretation of newman’s ( ) argument, that transformative learning is just learning, involving a total overlap of transformation and learning: transformation being another way of saying learning and learning another way of saying transformation. but, as a metaphor, which is arguably what mezirow was implying, transformative learning is about revolutionary enlightenment in a person’s psyche – neither simply a learning of skills or ideas, nor simply an awakening in some spiritual sense, but an awakening that leads to new learning that otherwise would not have occurred. there are a number of other terms that are woven throughout the theory, and new ones are frequently being coined, all of which are also arguably metaphors, supporting the argument that the theory operates as a conceptual metaphor: transformative relationships, transformative rationality, transformative context, transformative experience, transformative effects, transformative potential, transformative discourse, and others (daloz, ; kegan, ; mezirow, ; mezirow, taylor, and associates, ; taylor, ). in these instances, the source domain of transformation can be seen as being applied repeatedly to different target domains in this conceptually metaphoric manner, cognate to that of transformative learning (lakoff & johnson, ). the theory may thus be seen as capturing the central features of both a parable and an extended metaphor (both areas not generally covered in conceptual metaphor theory). a parable is being seen here as a short allegorical, yet familiar, story told to illustrate a moral, ethical or teaching point, such as the stories of the new testament bible described as being told by jesus, and aesop’s fables. an extended metaphor has been described by pillar ( ) as a metaphor that is consciously sustained throughout a text or discourse, such as shakespeare’s th sonnet, ‘shall i compare thee to a summers day’ and, from ‘as you like it’, ‘all the world's a stage and men and women merely players’, both of which continue the metaphor throughout the work or for an extended period. the exact metaphorical designation of the theory is beyond the scope of this paper. however, it can be seen that the theory, through the ongoing nature of the source domain, transformation, being applied to more and more aspects of learning, is also operating as a hybrid of extended and conceptual metaphors, indicated by its inclusion in such a sustained and ongoing manner as the central story in many conferences, books and journals. arguments for the theory as a metaphor transformative learning theory has not only proven to have great staying power as an idea, but also to be a prolific producer of offshoots and closely related ideas (mezirow and associates, ; mezirow, taylor, and associates, ), in spite of the fact that there are deficiencies in its application and perhaps in the theory itself (taylor, , ). there is a raft of small but consequential and unanswerable questions problematising the theory, which have been raised by a variety of theorists in many critiques. by treating the theory as a conceptual metaphor, these many inconsistencies – together with the fact that they are largely ignored when they are raised, and the theory’s continued popularity among educational practitioners – not only make sense, but actually serve to unify the theory. the interwoven problematic areas of the theory that constitute arguments for interpreting it as a metaphor are those of: its unidirectional theorising, its lack of critiquing of the theory in the literature, the failure to validate it, its lack of quantifiability, the problematic nature of its exemplary cases, the failure of elements such as the disorienting dilemma to contribute effectively to it, its lack of predictiveness, its selective attention to research outcomes, an uncritical acceptance of its theoretical solidity, terminological meaninglessness, theoretical unboundedness, and its colonisation of other adult learning concepts. these arguments are articulated and exemplified in the following sub-sections. unidirectional theorising the unidirectional nature of theorising sees the theory as having led to new applications and theorisations of forms of learning, but with little or no impact on the theory itself (cranton and taylor, ). instead, the theory has tended to be kept much as originally stated, but with a diffusion of meaning evidenced by increasingly ambiguous language, and the heightened use of theory jargon, rendering the theory increasingly metaphorical. for instance, in mezirow’s ( ) early articulation, a frame of reference and a meaning perspective were treated synonymously, with each being used to illuminate the other. eighteen years later, mezirow wrote that frames of reference were structures on which our expectations of and assumptions about our thoughts, feeling and actions were based (mezirow, , p. ). he also added that they may be, ‘rules, criteria, codes, language, schemata, cultural canon, ideology, standards, or paradigms’ and may also include, ‘personality traits and dispositions, genealogy, power allocation, worldviews, religious doctrine, aesthetic values, social movements, psychological schema or scripts, learning styles, and preferences’ (mezirow, , p. ). it is thus important to note that a frame of reference may also be, ‘a predisposition with cognitive, affective, and conative (striving) dimensions’ (mezirow, , p. ). it is hard to avoid the conclusion that a frame of reference might be almost any aspect of a person’s identity, and that any change in it may constitute a transformation. indeed, mezirow ( , p. ) also claimed that ‘transformative learning may be understood as the epistemology of how adults learn to reason for themselves’, which is a striking generalisation, as it defines all adult learning that impacts on reasoning as transformative learning. this universalisability of the concept has been underlined by generalizations, such as those of kasl and elias ( ), who wrote that transformation, in the theory, is the expansion of consciousness in any human system, collective as well as individual. these examples provide support for the theory being a conceptual metaphor, which permits such generalizations or extensions. lack of critique that there is a lack of critiquing of the literature on transformative learning theory in the literature has been pointed out repeatedly by taylor ( , a, ), and taylor and snyder ( ), who have made the point that much writing on the theory, apart from being redundant, does not build on, critique, or otherwise challenge other writing in the community of transformative learning theorists. while taylor has noted this point, and has done so more than once, he has avoided speculation as to why this might be so, and why there has been such a lack of attention to his raising the issue in the first place. while the work of kucukaydin and cranton ( ) does provide an example of a critique of others’ writing, it focuses not on the theory, but on certain writers’ attempts to include the extrarational approach into the theory. while kokkos ( , p. ) has observed that there is a convergence amongst scholars of the theory that the conscious and the unconscious dimensions of learning are important, he has also pointed out that they also have different views on the theory’s ‘components and its methods’. unfortunately, he continues the article in an entirely other direction, leaving what is arguably a challengingly bold statement, entirely unaddressed. and stevens-long, schapiro, and mcclintock ( ) have pointed to the muddied nature of the way the language is used differently by different researchers and practitioners. after a -year exposure to the theory, and after its being considered the new andragogy, the tardy response of transformative learning theorists to such self- generated issues, points to the theory being a conceptual metaphor. failure to validate the failure to validate the theory has also been noted by cranton and taylor ( ), who have pointed out the lack of substantive knowledge of the theory’s impact on grades, test scores, or performance. taylor ( b, p. ) had already noted that, ‘despite all the rhetoric on promoting transformative learning in the adult education classroom, there is little research about its impact on learner outcomes’. the main the extrarational approach is here aligned with jungian depth psychology, and relates to the areas of feeling, imagination, intuition, and dreams (kucukaydin & cranton, ). research focus in the theory over the last two decades has remained one of using qualitative research methodologies to show that transformative learning of one type or another has occurred (cranton and taylor, ; taylor, , ; taylor and snyder, ). this focus has produced numerous data sets for which one explanation has been given: an explanation which has been generalized to the status of an adult learning theory. the sheer volume of the data suggests that the theory has been verified, but in reality, the data have been sought through the self-confirming framework of the theory. as taylor and snyder ( , p. ) have noted: there was a lack of theoretical analysis of the findings affirming or questioning the underlying assumptions found in the theoretical framework. instead there is a tendency to be too deterministic where the data seems to fit easily, and to be unquestionably supportive of the theoretical framework, particularly mezirow’s orientation. as a conceptual, metaphor the theory does not require validation, nor does it create the conditions to bring about a drive to provide more than face validity. lack of quantifiability the lack of quantifiability of the theory has been noted by cohen and piper ( , p. ) who, while writing about the neglected role of environment and other non- rational elements that can drive a transformative learning process, mention that ‘we can’t precisely measure the transformative learning we have witnessed…’, but they comment no further on this lack of quantifiability. it is an important lack, because it leaves the theory subject to the vagaries and subjectivities of researchers and research participants in determinations of whether or not a transformative learning experience has occurred. that agreed measures have not been developed points to a problem with the theory, as does the lack of discussion of this failure. the lack of measures, let alone agreed measures, means that it is impracticable to discern either the similarities or the differences between the findings of different researchers. merriam and kin ( , p. ) have pointed out that there are ‘only a few studies of transformational learning that have attempted to measure a change in perspective.’ brock ( ), while attempting to measure the outcomes of each of the steps in the theory, showed that the longer students were in the institution she targeted for her research, the more transformative learning they supposedly experienced. thus, the longer brock’s participating students were in the institution, the more they learned, which is unexceptional, and this as much as anything provides further support for newman’s ( ) contention that transformative learning is nothing more or less than learning. indeed, cranton and taylor ( , p. ) have suggested that, due to the overwhelmingly qualitative nature of much of the research into the theory, it could be time to develop some empirically validated sound quantitative survey instruments for the assessment of the process of transformative learning and the outcome of the process. this lack of agreed measures and, until recently, a lack of acknowledgement of the significance of this lack, is another argument that points to the theory being a conceptual metaphor. problematic exemplary cases the problematic nature of exemplary cases has not been acknowledged in the literature to date. cranton and taylor ( , p. ) have pointed out that there are some reported outcomes from the application of the theory. however, the works to which they refer highlight a further series of minor, yet unaddressed, problems with the theory. for instance, donaldson ( , p. ), the first source cited in the article by cranton and taylor just mentioned, suggests that ‘transformative learning begets transformative learning’ and his writing suggests that deepening understanding is synonymous with transformative learning. this is problematic because it is so general and broad as to be meaningless and, if left to stand unaddressed, implies firstly that transformative learning is as simple as deepening understanding and, secondly, that another precursor for transformative learning is now transformative learning itself, which undermines any empirical purchase of the theory, as it is only self-referential and recursive. unless it is treated as a purely metaphorical observation, it is problematic. in cranton and taylor’s second source in which transformative learning outcomes are reported, easton, monkman, and miles ( , p. ) describe participants as clearly having ‘transformed their lives in the process’, although ‘it is more difficult to identify just what measures and methods are most directly transformative in the program.’ this lack of capacity to identify what transforms is problematic and representative of much of the research, in which outcomes are purported to be transformative while the causal mechanisms remain unarticulated and unclear. in the third example, cranton and taylor, macleod and egan ( , p. ) refer to transformative processes that may or may not be successful in bringing about any transformative learning in their students, some of whom described feelings of threat, discomfort and alienation. the mechanisms that may be at play are unarticulated. these are problematic examples of the theory in action, rather than exemplary ones, and they point to the metaphorical nature of the theory. elemental failures the failure of elements such as the disorienting dilemma to contribute effectively to the theory is grounded in the reality that the steps developed for the theory are themselves somewhat metaphorical. mezirow’s (mezirow & marsick, ) account of the steps acknowledges them as more of a description of praxis than theory. the disorienting dilemma, then, as a construct, is problematic, because the nature of dilemmas is treated differently by different theorists, with so little commonality as to render the concept almost meaningless. daloz ( ), for instance, reported that he had found little evidence for other than incremental transformative changes, and he practically did away with the need for disorienting dilemmas by downgrading them to moment-to-moment life challenges. taylor ( a) has pointed out that, despite the research activity, there is a lack of theoretical understanding as to why some disorienting dilemmas lead to transformations and others do not, and alhadeff-jones ( ), drawing on taylor’s comments, has suggested that the whole notion of linear causality in the theory, such as a first step being the disorienting dilemma, is flawed. cranton and wright ( ) have suggested that a disorienting dilemma may be no more than an activating event that leads a person to engage in further training, which, due to the skills of the teachers, keeps and holds the learners’ attention until he or she ends up with a transformative learning experience. it can be argued that the disorienting dilemma has been watered down to include almost any life event. the argument appears to be that the disorienting dilemma is real because a student is required to take on a world view that is different from their own and hence they are disoriented. however, given that this is a central purpose of education, it is difficult to see how, in the spirit of the theory, it can seriously be seen as a disorienting dilemma or anything other than good teaching or learning, as newman ( ) has asserted. this is further indication that the theory is operating as a conceptual metaphor, as these discrepancies appear to raise no concerns. lack of predictiveness the lack of predictiveness of the theory may be a function of its descriptively grounded development. grounded theory is a methodology intended to create a theory to fit a specific selection of data (chamaz, ). the newly created theory, ideally, thus descriptively fits that specific selection of data. we can, theoretically, have confidence that the theory at least fits those data, but we have no grounds for generalisation beyond them. repeated descriptive research studies confirm, over and over again, the descriptive veracity of the theory, but they contribute nothing to its explanatory or predictive power. the desire to confirm the descriptive utility of the theory in all research situations denies any opportunity to sharpen it to the point that it has any explanatory or predictive power since, to achieve such power, entails a denial of the unbounded interpretation of its key concepts. the theory thus denies any possibility that it could be used to make predictions about the world or to guide educational practise in any empirically-informed manner (schafersman, ). cranton and taylor ( , p. ) have pointed out that little is known about the impact of transformative learning in the traditional area of formal education: grades, test scores, and performance. the argument here suggests that this is entirely to be expected, since that impact is unknowable, given the theory’s lack of predictiveness. it is further evidence of the purely metaphorical nature of the theory. selective attention to research outcomes the selective attention to research outcomes may be seen as ensuring the perpetuation of the theory’s weaknesses. for instance, there is a lack of replicability of the disorienting dilemma as a reliable kick-start to the transformative learning process (taylor, a). apparently, a disorienting dilemma does, on occasion, kick-start the process described by the theory but, on other occasions, it does not. this suggests that there are elements in transformative learning for which the theory cannot account. and not only are those elements unaccounted for, but they are of significance, and they remain unacknowledged. a theory that relies on cherry-picking the positive research responses that fit its view of the world is problematic. along with the lack of response to this conceptual problem, alternative understandings have not been sought for the same data. in the literature on transformative learning theory, there is no acknowledgement, investigation, or consideration of similar experiences not gained through the processes elucidated in the theory. neither is there any acknowledgement of experiences of perspective transformations that have not been positive, expansive, creative of flexibility, and so on. it may be suggested in this regard that published research on the theory fits into a one of four categories: ( ) that which produces data that can be described as fitting into the theory or approximate versions of it; ( ) that which supposedly further explicates elements of the theory (such as what is a meaning perspective? (cranton and taylor, ); ( ) that which combines elements of the theory, either in part or in total, with other models of learning or human functioning (e.g., transformative learning and jungian depth psychology in dirkx, , ); and ( ) that which uses the theory to stretch the boundaries of what otherwise might not be considered either learning or legitimate research into adult learning (tisdall, ). thus far, there has appeared little research that considers such questions as what else could be happening? why does it appear to work for one person and not another? why is it not replicable? what is this disorienting dilemma? and what is it that is taking place here? in short, the selective use of research to confirm the theory points to its functioning as a conceptual metaphor. uncritical acceptance of theoretical solidity the uncritical acceptance of the theory’s theoretical solidity has become increasingly apparent over time. returning to the methodological limitations of the grounded theory approach to the theory’s formulation, glaser and strauss ( ) have argued that grounded theory may lead to the discovery of new theory, and this is certainly how this theory is treated by many: as a reality discovered (chamaz, ): as a thing that is out there to be researched, elucidated, explicated, polished, and refined, rather than as an explanatory and predictive interpretation of experiences and phenomena. it thus tends to be seen as a given, from which to view other data and theories (cranton & taylor, ). treating the theory as though it described an existing entity permeates the literature on the subject and lends support to seeing it as a conceptual metaphor. research grounded in the theory all progresses on the understanding that a transformative learning process exists and that it was discovered, unearthed, described, and clarified in its theorisation. the theory has thus been identified as an objective truth, despite mezirow ( , p. ) being insistent that it was simply the best judgment of people in this field of endeavour, and kucukaydin and cranton’s ( , p. ) suggestion that ‘knowledge about transformative learning has been constructed by a community of scholars working to explain how adults experience a deep shift in perspective that leads them to better justified and more open frames of reference.’ the uncritical acceptance of the theory’s solidity is exemplified by mälkki ( , p. ) who, in using the theory, asserted that it ‘has been validated through numerous empirical studies...’, giving seven references in support of this claim, none of which is grounded in empirical research that could be said to provide any validation of the theory. often it appears as though scholars of transformative learning theory are uncritical when using the work of other writers to support their contentions. in this instance, the cumulative lack of causal clarity, or evidence, is yet another feature of the theory, unremarked on by its protagonists, and a further indication of its power as a conceptual metaphor. terminological meaninglessness the terminological meaninglessness in the theorisation of transformative learning theory is consistent with the points already noted. brookfield ( , p. ) lamented the use of the word transformative for any instance of reflection that leads to any modification of assumptions, no matter how trivial, and tisdell ( , p. ) pointed out that it is used by many people as a synonym for any kind of learning. kegan ( , p. ) suggested that the appealing nature of the language leaves it open to being used for a variety of purposes, its meaning becoming distorted, and its distinctive idea becoming lost, to the extent of its taking on quasi-religious qualities. this is an indication of the problematic metaphoric character, in this context, of the word transformative. in this instance, the word is being used as a term to highlight a change, while at the same time trying to imbue it with gravitas and kudos: as nothing less than a transformation (brookfield, ). kegan ( , p. ) has suggested that the there needs to be an epistemological narrowing of the way the term is used, while brookfield’s solution to this problem is to narrow its focus to critical self reflection on assumptions (just one element of the present theory). others have criticized the theory as being too narrow, or have reported such criticisms by others, because it relies as it does on the centrality of rationality in learning (cranton, ; mezirow, ; taylor, , ), while belenky and stanton ( ) have suggested that the theory focuses too narrowly because it does not trace the many steps people take before they know how they know, by focusing just on the endpoint of development. there is no general agreement about what is and what is not transformative learning, or the difference between transformative and other learning. these kinds of limitations are explicable through considering the theory as a conceptual metaphor. theoretical unboundedness the unboundedness of the theory is evidenced in the continuing multiplication of educational outcomes that are identified as being transformative. we are now faced with the situation where any personally significant learning experience or consciousness-raising process, such as learning to become a less conservative person, becoming a more conservative person, turning suddenly vegetarian, or becoming ‘green’, and such like is argued to be transformative learning. this is done irrespective of whether or not the other aspects of the theory are accounted for, or whether or not there has been any serious analytical investigation of the adequacy of either the theory, or the conceptual overlaps between it and the changes being described to have occurred to individuals (brookfield, ). this unboundedness of the theory contributes further to its raft of unanswered or unanswerable questions (cranton and taylor, ; newman, ) and argues for its metaphorical nature since, as such, the unboundedness becomes unproblematic. colonisation of other concepts that unboundedness, effectively allows the theory to colonise a host of other adult learning concepts: processes which, in and of themselves, have been recognised independently of the theory, but which now can be defined as processes that bring about a transformative learning experience. engagements such as peer reflection and critical reflection thus become subsumed under the rubric of the theory (brookfield, ). everything that encourages reflection on assumptions becomes part of the theory. it can be argued that researchers are working to tie particular types of adult learning to the transformative learning bandwagon, as for example, in: adria’s ( ) ‘transformative learning through deliberative dialogue’; brendel’s ( ) ‘narrative driven transformative learning among hospice patients’; and hunt’s ( ) ‘creative writing as a tool for transformative learning’, each author has presented a learning tool as a transformative process. the theory seems to be taking over the adult learning world by stealth and inattentiveness, rather than thoughtfulness. it thus becomes the organising framework for a variety of other approaches to adult learning, all of which are assumed to be transformational. when this occurs, the whole theory becomes suspect, because it effectively lacks any real boundaries, and without boundaries, it becomes incoherent and meaningless (brookfield, ; newman, ; tisdell, ), albeit a beautiful metaphor. to quote taylor and cranton ( , p. ): most significantly, its [transformative learning theory’s] ubiquitous presence beyond the field of adult education has led to a construct that has come to mean many things to many educators. implications of this perspective the proposition of the theory being a conceptual metaphor has a number of implications that are considered in this section. for a start, the theory as a conceptual metaphor is fruitful in practise. according to arbusson, harrison, and ritchie ( ), a research and teaching metaphor should allow an imaginative leap between known and unknown ways of thinking that then allows for further planning, thinking, conceiving, research, and action to take place. this has proven to be the case here, with the metaphor facilitating leaps of imagination from previous conceptions of learning, consciousness raising, and what are legitimate areas of adult education, to the idea of transformative learning theory as a new, special, and different arena of adult learning, ripe for further exploration. the conceptual metaphor in this case serves the purpose of generating an image of learning as a transformative experience, which then provides the basis for the research, theorising, and practise that follows. the theory as a metaphor may also be seen as stimulating academic enquiry and investigation into hitherto unexamined human learning processes relating to significant shifts in individuals’ conceptions of themselves, the world, and how the world works. seeing the theory as a conceptual metaphor also stimulates discussion and dialogue. the need to be emphatic about trying to establish the theory as ‘real’, ‘true’ or ‘valid’, is thus rendered inconsequential. in effect, it is frees up the discussions that can be had through the theory. as a metaphor, it can be extended, modified, reformulated, added to, redefined, re-envisioned, and played with to almost any extent, just as can be done with metaphors generally. it is this technical capacity of a metaphor that allows imagination to be used when working with theory construction (morgan, ). this is what appears to have happened in many instances in the ways in which the theory has been applied by researchers and practitioners. consider for instance, the titles of the following presentations from amongst a wide range of equally diverse presentations from the eighth and ninth international transformational learning conferences; they show great invention and creativity by looking at photography, music, contemplative education, and parenting through the lens of the theory: ‘looking at the world through multiple lenses: photography as transformative learning’ (lawrence and cranton, ), ‘balance on the water: jimmy buffett [the popular musician] as transformative philosopher and guide’ (feller, ), ‘the art of contemplation-oriented transformative facilitation: a perspective from thailand’ (nilchaikovit, ), and ‘transition to parenthood: a qualitative study using the theory of transformative learning’ (klobucar, ). as a conceptual metaphor, the theory also lends itself to being applied in a diverse range of contexts that a more rigorous theory might not immediately permit. contemplative education is ‘an education that enable[s] one to truly know one’s mind and hence gain wisdom, which means reaching the ultimate truth or reaching the truth the beauty and the good’ (wasi, ; as quoted in nilchaikovit, , p. ). indeed, it has been applied widely and imaginatively, as the examples given in the paragraph above illustrate. examples of the broad range of applications (as distinct from the purely imaginative applications) that practitioners are making with the theory can readily be seen in a recent book from mezirow, taylor, and associates ( ). in that book, there are articles on applications of transformative learning to community and social change, such as women’s education and work in bolivia, farming schools in rural west africa, and the empowerment of women in east harlem, usa. there are applications to education in corporate america, workplace learning, coaching, developing critical reflection, and in adult basic education. there are applications in higher education to practises such as mentoring, culturally responsive teaching, promoting dialogical teaching in academic faculties, and palliative care education. looking at the proceedings from conferences also points to a great diffusion of the idea of the theory into diverse areas. this paper makes the argument that this is possible precisely because the theory is a conceptual metaphor, allowing it to be widely applied, in this case, in an inspirational manner. treating the theory as a conceptual metaphor also gives insight into the absence of research into the fundamentals of transformative learning, an issue raised earlier in this paper. as a metaphor, the theory serves to stimulate practitioners and researchers to apply it and experiment with it in their practice, and to extend its uses. it reduces or even eliminates altogether the need to undertake fundamental research. the critical faculties that might be brought to bear on a more thorough research-based and peer-assessed theory have been rendered redundant. consequently, intellectual effort is focused on repeated applications of the theory as a way of explaining changes in adult students, or of preparing ways to interact and teach adult students in a wide variety of situations. such redundancy of research into transformative learning that simply applies the theory to new situations is a natural consequence of its serving as a conceptual metaphor. treating the theory as a metaphor also makes sense of it being treated at times as more than a theory, and more like a general truth. taylor, and others, have identified the paucity of fundamental research into the theory, and the plausible implication that it has become reified (brookfield, ; cranton and taylor, ; taylor, , ). considering transformative learning as a conceptual metaphor makes sense of this issue. arguably, if we are dealing with a metaphor, the better the metaphor, the more it will lend itself to reification and hence uncritical acceptance. howard ( ) suggests that the more closely the metaphor resembles the lived experience of students, researchers and teachers, the more likely it is to be accepted, as it is, and on its own terms, regardless of informing research or its absence. the face validity of the theory, in reality a conceptual metaphor, tends to overcome concerns about its underlying inadequacy. it reduces the felt need for adequate theoretical exploration and research on the part of practitioners and academics alike. while mezirow in each explication of his theory has been substantively true to the original presentation, he has introduced language that itself remains uncontested and undefined. conceiving transformative learning as a conceptual metaphor renders acceptable this redundant, creative and poetical use of language. conclusion it has been argued here that transformative learning theory has a telling array of inadequacies as a theory of learning, in spite of which, it has been widely accepted and adopted: an apparent anomaly that is explicable through seeing the theory as a conceptual metaphor. recognising transformative learning theory as a conceptual metaphor, albeit a metaphor masquerading as a theory, has allowed it to be applied and used in a wide variety of settings, while remaining immune to critical inquiry. the notion of transformative learning theory as being essentially metaphorical in nature, may thus be seen as providing an explanation for newman’s ( , p. ) telling speculation from his critique that: this leads me to wonder whether transformative learning only exists in the realm of theory. perhaps it is a plaything of the mind, about which we can argue the toss, but which has little or no basis in everyday practise. michael, it does not even exist in the realm of theory, but as a conceptual metaphor in a manner that theory cannot hope to attain to. references adria, m. 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( ). an empiricist's musings about reality, evidence, and data: accumulating support for transformative learning. journal of transformative education, , - . ep journal - product research & review center skip to content ep journal main menu reviews blog about contact us privacy policy best dry bags – keep your items safe from getting wet leave a comment / reviews / by william going on a trip and need to keep your items safe? then having one of the best dry bags will be a great choice. we know how annoying it can be to end up with all your items soaked in water. they end up all smelly and sometimes totally unusable. luckily, you can always prevent … best dry bags – keep your items safe from getting wet read more » best waterproof jacket in – stay dry in adverse weather leave a comment / reviews / by william it doesn’t matter where you go – being safe is always crucial to getting a good time. and sometimes that means bringing the right jacket. if you’re going to a trip in a snowy mountain, a place with lots of humidity, or anywhere with cloudy weather – then you’ll want the best waterproof jacket to … best waterproof jacket in – stay dry in adverse weather read more » best snorkel masks in – expert reviews! leave a comment / reviews / by william setting up a scuba diving trip demands a lot of time and money. just getting an oxygen tank and all the breathing equipment will take several hundred out of your bank account, and several hours of preparing. luckily, if you want to go scuba diving but don’t have the money – then going snorkeling can … best snorkel masks in – expert reviews! read more » best sun hat in – editor choice leave a comment / reviews / by william engrossed in search of the essential companion in this scorching heat for your must-have summer plans? 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( ) now present two crystal structures of hdohh, one of the peroxo-diiron(iii) intermediates, and the other of a complex with glycerol. through time-dependent uv/vis spectra of the intermediate, which is colored blue (absorption maximum at � nm), they show that the peroxo species, which they have crystallized, does not corre- spond to the one formed immediately af- ter the reaction of the reduced form of hdohh with o , but to a slightly different one obtained over the time of crystalliza- tion ( hr). this is supported by mössba- structure , may , uer spectra of the fe-hdohh in the crystals, which differ slightly from those obtained from freshly prepared hdohh in solution. in any case, han et al. describe here the crystal structure of a native peroxo intermediate of a non- heme diiron enzyme. the . å struc- ture reveals a cis-m- , arrangement (cis-h ,h - , ; scheme i of figure a) of the peroxo unit, with a gauche fe-o-o- fe torsion angle. remarkably, the o - atom of the peroxide is more centrally placed between the two iron atoms ( . and . å from fe and fe , respectively), whereas o is basically interacting only with fe ( . and . å from fe and fe , respectively) (figure b). while this asymmetric arrangement is still cis-m- , (h ,h - , ), it is not far from an h ,h - , arrangement (v of figure a), a configura- tion that has very recently been proposed on the basis of spectroscopic data for the peroxo intermediate of a bacterial aryl oxygenase (makris et al., ). the lack ª of true isosbestic points in the time-dependent uv/vis spectra re- ported by han et al. ( ) suggests that the peroxo intermediate may adopt a continuum of configurations and this may be reflected in the slight differences observed between the two molecules in the asymmetric unit of the hdohh crystal. the crystallographic work of han et al. also reveals the reason for the unusual stability of the peroxo inter- mediate of hdohh: in contrast to all other well-characterized non-heme diiron enzymes, hdohh features a histidine-rich coordination of the diiron core lacking any bridging car- boxylates. the histidines coordinate iron through their nε-atoms, not elsevier ltd all rights reserved mailto:grueber@ntu.edu.sg http://dx.doi.org/ . /j.str. . . http://crossmark.crossref.org/dialog/?doi= . /j.str. . . &domain=pdf figure . peroxo-diiron(iii) core (a) possible geometries for the peroxo-diiron(iii) core of diiron-containing oxygenases; (b) fo-fc difference density (contoured at . s) for the non-protein ligands of the diiron core of hdohh. the corresponding difference map was calculated after building the protein ligands but before incorporating the peroxo, and water ligands. structure previews their nd-atoms as in most other diiron oxygenases. furthermore, the secondary ligation hemisphere surrounding the bind- ing site for the peroxide ion is very hydro- phobic, shielding the reactive intermedi- ate by a methionine pair and a leucine pair. importantly, potential hydrogen- bonding donors such as threonine, which occur in many o -activating monooxyge- nases, where they seem to shuttle pro- tons to the active site (wallar and lips- comb, ), are completely absent from the hdohh active site; therefore, the heterolytic breakdown of the peroxide resulting from protonation is greatly delayed. a high-oxidation state intermediate such as compound q has so far not been described for hdohh, and perhaps there is no requirement for it. in the smmoh system, q is the active species that breaks the unusually strong (dh = kcal mol� ) c-h bond in methane to insert oxygen. however, the peroxo-diiro- n(iii) intermediate p of smmoh is by itself able to oxidize electron-rich hydrocar- bons such as diethyl ether or propylene structure , may , ª elsevie (indicated by the direct pathway between p and hox in figure ) (tinberg and lip- pard, ). there is only one substrate known for dohh: deoxyhypusine eukaryotic trans- lation initiation factor a (eif- a). the various functions of this protein in transla- tion initiation and elongation (in particular of oligoproline-containing polypeptide segments) and in nuclear export of retro- viral rna, cd mrna, and inos mrna depend on the elongation of an exposed lysine residue (k in the human protein) by attachment of a -hydroxo- - amino butyl unit. this unique posttransla- tional modification is performed in a two-step reaction catalyzed by the en- zymes deoxyhypusine synthase (dhs) and dohh (park, ). in the first step, dhs attaches a -aminobutyl group orig- inating from spermidine to the nz atom of residue k , to yield deoxyhypusine-eif- a (dhp-eif- a). in the second step, dohh hydroxylates dhp-eif- a in the -position of the -aminobutyl group, thereby affording hypusine-eif- a (hpu- eif- a). the structures presented by r ltd all rights reserved han et al. ( ) immediately suggest how the substrate and the product would bind to human dohh. this in itself is a major achievement, as hdohh could well act as a target for the development of therapeutics for the treatment of hiv/ aids, certain cancers, and diabetes (kai- ser, ). references banerjee, r., proshlyakov, y., lipscomb, j.d., and proshlyakov, d.a. ( ). nature , – . han, z., sakai, n., böttger, l.h., klinke, s., hauber, j., trautwein, a.x., and hilgenfeld, r. ( ). structure , this issue, – . kaiser, a. ( ). amino acids , – . liu, k.e., valentine, a.m., qiu, d., edmondson, d.e., appelman, e.h., spiro, t.g., and lippard, s.j. ( ). j. am. chem. soc. , – . makris, t.m., vu, v.v., meier, k.k., komor, a.j., ri- vard, b.s., münck, e., que, l., jr., and lipscomb, j.d. ( ). j. am. chem. soc. , – . park, m.h. ( ). j. biochem. , – . solomon, e.i., brunold, t.c., davis, m.i., kemsley, j.n., lee, s.k., lehnert, n., neese, f., skulan, a.j., yang, y.s., and zhou, j. ( ). chem. rev. , – . tinberg, c.e., and lippard, s.j. ( ). biochem- istry , – . tinberg, c.e., and lippard, s.j. ( ). acc. chem. res. , – . vu, v.v., emerson, j.p., martinho, m., kim, y.s., münck, e., park, m.h., and que, l., jr. ( ). proc. natl. acad. sci. usa , – . wallar, b.j., and lipscomb, j.d. ( ). chem. rev. , – . xue, g., fiedlera, a.t., martinho, m., münck, e., and que, l., jr. ( ). proc. natl. acad. sci. usa , – . the beauty of a visualized peroxo-diiron(iii) intermediate references jurnal sarjana dis mac going global: branding strategies in the malaysian beauty industry shakila yacob & rosilawati zainol abstract !"#$%&'#%()*&%+#,)+#%-.&/.-*%. % #) & %')"#% ##-% -+#$ ./- %*/ -/ ,)-&%&$)-* .$ )&/.-% /-% ) ) */) %:'$. '%/-&#$"/#;*%;/&'% )-) #$*%)-+%.;-#$*%/-%&'$##%# #$ /- % #) & % ,. 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()-/#* %:'/*%&$#-+%')*%#-) #+%/-+/ #-. *%?-.; #+ #%&.% #%$#"/"#+<%($#*#$"#+%)-+% $#a/-&$.+ ,#+ %:' *<%&'#%)$&%. %/-+/ #-. *%?-.; #+ #%/*%-.&% .*&% .$#"#$%&.%(.*&#$/& %.$% $# )/-%'/++#-%&.%&'#% -/-/&/)&#+ %g#-,#<%,. #$,/) /*)&/.-%')*% #)-&%&'#%+/ */.-%. % jurnal sarjana shakila .indd / / : : going global: branding strategies in the malaysian beauty industry /-+/ #-. *%?-.; #+ #% # .-+%&'#%&$)+/&/.-) %,.- -#*<%/-% ),&%* ,'%?-.; #+ #%/*%-.;% reaching a global audience. % :'#% ) ) */)-% ."#$- #-&%')*% ##-%)% #)+/- %($.(.-#-&%. %/-+/ #-. *% ?-.; #+ #%)-+%&'$. '%")$/. *%) #-,/#*%')*%* ((.$&#+%#-+#)". $*%&.%($. .&#%/&*% *# %l &'. '%&'#% ., *%. %&'#% ."#$- #-&% ) % #%($/ )$/ %&.%#-,. $) #%&'#% *#% . % .,) %'#$ *%&.%/-,$#)*#%'#) &'%,.-*,/. *-#**%) .- %&'#%(.( )&/.-<%)*%'#) &'%)-+% #) & %)$#%/-#b&$/,) % /-?#+%/-%&'#% ) ) %,. -/& %&'/*%')*%) *.% #-# &#+% .,) % #) & %,. 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()-/#*<%/*%;# a(./*#+%&.%(.*/&/.-%/&*# %)*%&'#% #)+/- %($.+ ,#$% . % #) & %($.+ ,&*% .&'% .,) %)-+%/-%)%- #$%. %($/-,/() % * / %,. -&$/#* % note s% %r')?/ )%q),. %/*%)-%)**.,/)&#%($. #**.$%)&%&'#%i#()$& #-&%. %g/*&.$ <%y), & %. %l$&*%)-+% r.,/) %r,/#-,#*<%v-/"#$*/& %. % ) ) ) %c.*/ );)&/%k)/-. %/*%)%*#-/.$% #,& $#$%&'#%i#()$& #-&% . %v$ )-%_%c# /.-) %^ )--/- <%y), & %. %e / +%j-"/$.- #-&<%v-/"#$*/& %. % ) ) ) jurnal sarjana shakila .indd / / : : going global: branding strategies in the malaysian beauty industry references <%wxxx %]#;%f#+)'%( )-&%*#&%&.% ..*&%].-)%c. %'#$ ) %#b(.$&*. chemical business<%ww%]."# #$ % <%wxxc %c.=/&)%h%i)$/%'#$ )%?#%?/ )- %&#?*&/ . utusan malaysia<%w% ) % <%wxxd %r#-+) %:/- /%*##?*%&.%/-,$#)*#%*) #*%;/&'%-#;% $)-,'. bernama news<%c%l *& % l $);) <%_%l$ -<%wxxw d-+/ #-. *%?-.; #+ #%)-+%&'#%(. /&/,*%. %, )**/ /,)&/.- % unesco. l' )+<%l %r <%wxxf warisan perubatan melayu %f ) )%g ( $>%i#;)-%e)')*)%i)-% ^ *&)?) e)$)?' )'<%l <%wxxd %ensiklopedia perbidanan melayu %f ) )%g ( $>%l*/)-/*) e$)-+/-,<%wxx` %])&)* )>%) %/-%&'#% ) / %l.- /-#m%l")/ ) #%)&>%'&&(>jj $)-+/-, . *(.& ,. jwxx`jswj-)&)* )a) a/-a ) / '& %kl,,#**%wx%b -#%wxxam p')-+ #$<%_%l $#+<%i %b <%sttx scale and scope: the dynamics of industrial capitalism. p) $/+ #>%:'#%e# ?-)(%^$#** p')&&#$u##<%^ <%wxx` % )$?#&/- >%r')'-)=%g#$ ) % $)-,'#*%. &%&.%i )/<% ) ) */) business line,w%l *& % p' $,'<%_%c. <%%sttc %:'#% ) / % $ %/-%/-+ *&$/) %,)(/&) /* >%/-&#$-)&/.-) %(#$*(#,&/"#*% on hypotheses and history. business history, kem i)"/*<%b <%wxxa %:'#% ),#%. %,')- #>%*.,/) % #+/)\*%/ (),&%.-% #) & % $)-+/- %global cosmetic industry, .t%kdem h/ #&&#<%b %i <%st`s malay poisons and charm cures %r/- )(.$#>%!b .$+%^$#** h/ #&&#<%b %i <%_%:'. *.-<%g %o <%stct %a dictionary of malayan medicine %g.-+.->% !b .$+%^$#**%%v-/"#$*/& h. #<% )$,<%_%k )-<%r <%wxxs %emotional branding: the new paradigm for connecting brands to people%ki. %l ;.&'%^$#**m %]#;%q.$?>%]#;%q.$? h."#$- #-&%. % ) ) */)<%sttt %guideline for control of cosmetic products in malaysia, national pharmaceutical control bureau malaysia, third national agriculture policy ( ). h$# .$ <%c <%b <%_%o/#,' )-<%b %h <%wxxw branding across borders : a guide to global brand marketing %g.-+.->% ),h$);ag/ %^$. #*/.-) g) /=)<% %c <%wxxd %balancing health and beauty needs: women’s use of traditional and herbal medicines in evolving times.%^)(#$%($#*#-&#+%)&%&'#%e) )-,/- %g#) &'%)-+% e#) & %]##+*>%o. #-\*%v*#%. %:$)+/&/.-) %)-+%g#$ ) % #+/,/-#*%/-%j". "/- % :/ #*<%v^ jy.$#*&$ %i#()$& #-&%. % ) ) */) gip<%g %d %i %p <%wxxt %! ,/) %;# */&#%') ) %/-+ *&$ %+#"# .( #-&%,.$(.$)&/.- %l.- /-#m% l")/ ) #%)&>'&&(>jj;;; '+, . ) ,. %kl,,#**%a%b -#%wxxtm g# &)*/ ()<%r <%wxxe % .$#% ) .$)&.$/#*%]##+#+%&.%:)(%:')/ )-+%g#$ *%̂ .&#-&/) . knight ridder tribune business news<%st% ) % g. )-<%r <%l n /*&<%j <%_%h --<%r %j <%wxxf %e$)-+a / +/- >% -+/- %&'#%&. ,'(./-&*% that count. journal of business strategy, kwm g. &<%i %e <%wxxe %how brands become icons: the principles of cultural branding %p) $/+ #>% g)$")$+%e */-#**%r,'.. %^$#** b.-#*<%h <%wxxa %e .-+#%)-+% #a# #+n%h . ) /*/- % #) & <%, stefh, stax %economic history review, ks%kr($/- mm jurnal sarjana shakila .indd / / : : shakila yacob, rosilawati zainol`a f) <%h <%wxxf %!"#$%&'(&)*&)*+,'#-,./&' *& % '&-( & +-*& ( *'# & ( *$ &%*$ * &+$ & *+.' :. p. *<%!'/.>%:'#%!'/.%r&)&#%v-/"#$*/& f.#'-<%] <%wxxs %brand new: how entrepreneurs earned consumers’ trust from wedgwood to dell %e.*&.->%g)$")$+%e */-#**%r,'.. %^$#** g/ <%g <%wxxt ingredients for success<%ss%b % #$)-<%l %e <%wxxa %c);)&)-%r()% -& ?%f)-)?af)-)?. utusan malaysia<%st%b -# % -/$.<%f <%wxx` %])&)* ) %d-%p %^ %j % %r %e'+%kj+ m ] <%g <%wxx` %g#$ ) %p.--#,&/.-. malaysian business<%sd% )$,' % ^#/**<%f <%stta hope in a jar: the making of america’s beauty culture %]#;%q.$?>% #&$.(. /&)-% e..?* ^/)'<%g % <%wxxf %kitab tib: ilmu perubatan melayu %f ) )%g ( $>%^#$( *&)?))-% ]# )$)% ) ) */) ^ / <%] <%wxxc %:'#%*#)$,'% .$%/+#-&/& >%r()-/*'%(#$ #%/-%&'#%/-&#$-)&/.-) % )$?#& % business history, . kl & -m c#/* )-<%i <%wxxe %schumpeter’s market: enteprise and evolution %p'# &#-') <%vf>%j+;)$+% elgar. r)&'/*'<%i <%wxxt %p$),?+.;-%.-%,.* #&/,*% */- % )--#+%* *&)-,#*. emirates / , june. r,' (#&#$<%b %l <%stce %theory of economic development %p) $/+ #>%g)$")$+%v-/"#$*/& % ^$#** r,$)-&.-<%̂ <%wxxx %beauty and business: commerce, gender, and culture in modern america. ]#;%q.$?>%c. & #+ # r')$/ )'%l-/*)'<%i <%wxxa %].-)%c. %^$.+ ,& r/ "#$*&#/-<%b <% <%_%y/*?#<%] <%wxxc trading up: the new american luxury>%^.$& . /. r/ .-<%y$)-,./*#<%_%f.& #$<%^ <%wxxc %building global biobrands: taking biotechnology to market %]#;%q.$?>%r/ .-%_%r,' *&#$ :'#()$)&<%p <%_%l$ - )*<%^ <%wxxw :')/%g#$ ) ap.* #&/,%y/$ %j #*%jb(.$&*. knight ridder tribune business news<%s%b -# % o)' <%j %i <%wxxd %o. #-%)-+%p.* #&/,*>%:'#%g/*&.$ %. %l #$/,)-%e#) & %p & $# % narratives of technology kr($/- m o/-*&#+&<%c %! <%stas %the malays: a cultural history %r/- )(.$#>%h$)') %e$)*'%k^&#m%g&+ o. &#?<%c <%r'$. a #'&)<%̂ <%_% .')-<%̂ %p <%wxxe %indigenous knowledge: local pathways to global development’, marking five years of the world bank indigenous knowledge for development program. jurnal sarjana shakila .indd / / : : ar x iv :h ep -p h/ v j an beauty photoproduction at hera: kt -factorization versus experimental data a.v. lipatov, n.p. zotov january , d.v. skobeltsyn institute of nuclear physics, m.v. lomonosov moscow state university, moscow, russia abstract we present calculations of the beauty photoproduction at hera collider in the frame- work of the kt -factorization approach. both direct and resolved photon contributions are taken into account. the unintegrated gluon densities in a proton and in a photon are ob- tained from the full ccfm, from unified bfkl-dglap evolution equations as well as from the kimber-martin-ryskin prescription. we investigate different production rates (both in- clusive and associated with hadronic jets) and compare our theoretical predictions with the recent experimental data taken by the h and zeus collaborations. special attention is put on the xobsγ variable which is sensitive to the relative contributions to the beauty production cross section. introduction the beauty production at high energies is a subject of intensive study from both theo- retical and experimental points of view. first measurements [ ] of the b-quark cross sections at hera were significantly higher than qcd predictions calculated at next-to-leading or- der (nlo). similar observations were made in hadron-hadron collisions at tevatron [ ] and also in photon-photon interactions at lep [ ]. in last case, the theoretical nlo qcd predictions are more than three standard deviations below the experimental data. at teva- tron, recent analisys indicates that the overall description of the data can be improved [ ] by adopting the non-perturbative fragmentation function of the b-quark into the b-meson: an appropriate treatment of the b-quark fragmentation properties considerably reduces the disagreement between measured beauty cross section and the corresponding nlo qcd cal- culations. recently h and zeus collaborations have reported important data [ – ] on the beauty photoproduction (both inclusive and associated with hadronic jets) in electron- proton collisions at hera which refer to small values of the bjorken scaling variable x. these data are in a reasonable agreement with nlo qcd predictions or somewhat higher. some disagreement is observed [ ] mainly at small decay muon and/or associated jet trans- verse momenta. but the large excess of the first measurements over nlo qcd, reported [ ] by the h collaboration, is not confirmed. in the present paper to analyze the h and zeus data we will apply the so-called kt -factorization [ , ] (or semi-hard [ , ]) approach of qcd since the beauty production at hera is dominated by the photon-gluon or gluon- gluon fusion (direct and resolved photon contributions, respectively) and therefore sensitive to the gluon densities in a proton and in a photon at small values of x. the kt -factorization approach is based on the balitsky-fadin-kuraev-lipatov (bfkl) [ ] or ciafaloni-catani-fiorani-marchesini (ccfm) [ ] gluon evolution which are valid at small x since here large logarithmic terms proportional to ln /x are summed up to all orders of perturbation theory (in the leading logarithmic approximation). it is in contrast with the popular dokshitzer-gribov-lipatov-altarelli-parizi (dglap) [ ] strategy where only large logarithmic terms proportional to ln µ are taken into account. the basic dynam- ical quantity of the kt -factorization approach is the so-called unintegrated (kt -dependent) gluon distribution a(x, k t ,µ ) which determines the probability to find a gluon carrying the longitudinal momentum fraction x and the transverse momentum kt at the probing scale µ . the unintegrated gluon distribution can be obtained from the analytical or numerical solution of the bfkl or ccfm evolution equations. similar to dglap, to calculate the cross sections of any physical process the unintegrated gluon density a(x, k t ,µ ) has to be convoluted [ – ] with the relevant partonic cross section σ̂. but as the virtualities of the propagating gluons are no longer ordered, the partonic cross section has to be taken off mass shell (kt -dependent). it is in clear contrast with the dglap scheme (so-called collinear factorization). since gluons in initial state are not on-shell and are characterized by vir- tual masses (proportional to their transverse momentum), it also assumes a modification of their polarization density matrix [ , ]. in particular, the polarization vector of a gluon is no longer purely transversal, but acquires an admixture of longitudinal and time-like com- ponents. other important properties of the kt -factorization formalism are the additional contribution to the cross sections due to the integration over the k t region above µ and the broadening of the transverse momentum distributions due to extra transverse momentum of the colliding partons. some applications of the kt -factorization approach supplemented with the bfkl and ccfm evolution to the b-quark production at high energies were discussed in [ – ]. it was shown [ – ] that the beauty cross section at tevatron can be consistently described in the framework of this approach. however, a substantial discrepancy between theory and experiment is still found [ – ] for the b-quark production in γγ collisions at lep , not being cured by the kt -factorization . at hera, the inclusive beauty photoproduction has been investigated [ , , ] and comparisons with the first h measurements [ ] have been done. it was concluded that the kt -factorization approach provide a reasonable description some discussions of this problem may be found in [ , ]. of the data within the large theoretical and experimental uncertainties. in [ , ] the monte- carlo generator cascade [ ] has been used to predict the cross section of the b-quark and dijet associated photoproduction. however, all calculations [ , , ] deal with the total cross sections only. a number of important differential cross sections (such as transverse momentum and pseudo-rapidity distributions) has not been considered and comparisons with the recent h and zeus measurements [ – ] have not been made. in the present paper we will study the beauty production at hera in more detail. we investigate a number of different photoproduction rates (in particular, the transverse mo- mentum and pseudo-rapidity distributions of muons which originate from the semi-leptonic decays of b-quarks) and make comparisons with the recent h and zeus data [ – ]. both direct (γg → bb̄) and resolved photon contributions (gg → bb̄) will be taken into account . our analysis covers also both inclusive and dijet associated b-quark production. in last case special attention will be put on the xobsγ variable since this quantity is sensitive to the relative contributions to the cross section from different production mechanisms. one of the purposes of this paper is to investigate the specific kt -factorization effects in the b-quark production at hera. in the numerical analysis we test the unintegrated gluon distributions which are obtained from the full ccfm, unified bfkl-dglap [ ] evolution equations and from the conventional parton densities (using the kimber-martin-ryskin prescription [ ]). we would like to note that this study is the continuation of our previous investigations [ , ] where we have discussed, in particular, the charm production at lep [ ] and hera [ ]. the outline of our paper is following. in section we recall the basic formulas of the kt -factorization approach with a brief review of calculation steps. in section we present the numerical results of our calculations and a dicussion. finally, in section , we give some conclusions. basic formulas . kinematics we start from the gluon-gluon fusion subprocess. let pe and pp be the four-momenta of the initial electron and proton, k and k the four-momenta of the incoming off-shell gluons, and pb and pb̄ the four-momenta of the produced beauty quarks. in our analysis below we will use the sudakov decomposition, which has the following form: pb = α pe + β pp + pb t , pb̄ = α pe + β pp + pb̄ t , k = x pe + k t , k = x pp + k t , ( ) where k t , k t , pb t and pb̄ t are the transverse four-momenta of the corresponding particles. it is important that k t = −k t = and k t = −k t = . if we make replacement k → pe and set x = and k t = , then we easily obtain more simpler formulas corresponding to photon-gluon fusion subprocess. in the ep center-of-mass frame we can write pe = √ s/ ( , , , ), pp = √ s/ ( , , ,− ), ( ) the b-quark excitation processes bg → bg are automatically included in the kt -factorization approach, as it was demonstrated in [ – ]. where s = (pe + pp) is the total energy of the process under consideration and we neglect the masses of the incoming particles. the sudakov variables are expressed as follows: α = mb t√ s exp(yb), α = mb̄ t√ s exp(yb̄), β = mb t√ s exp(−yb), β = mb̄ t√ s exp(−yb̄), ( ) where mb t and mb̄ t are the transverse masses of the produced quarks, and yb and yb̄ are their rapidities (in the ep center-of-mass frame). from the conservation laws we can easily obtain the following conditions: x = α + α , x = β + β , k t + k t = pb t + pb̄ t . ( ) the variable xobsγ is often used in the analysis of the data which contain the dijet samples. this variable, which is the fraction of the photon momentum contributing to the production of two hadronic jets with transverse energies e jet t and e jet t , experimentally is defined [ , ] as xobsγ = e jet t e −ηjet + e jet t e −ηjet yee , ( ) where yee is the initial photon energy and η jet i are the pseudo-rapidities of these jets. the pseudo-rapidities ηjeti are defined as ηjeti = − ln tan(θjeti/ ), where θjeti are the polar angles of the jets with respect to the proton beam. note that the selection of xobsγ > . and xobsγ < . yields samples enriched in direct and resolved photon processes, respectively. . cross section for beauty photoproduction the main formulas for the total and differential beauty production cross sections were obtained in our previous papers [ , ]. here we recall some of them. in general case, the cross section σ according to kt -factorization theorem can be written as a convolution σ = σ ∫ dz z dk t c(x/z, k t ,µ )a(x, k t ,µ ), ( ) where c(x, k t ,µ ) is the coefficient function corresponding to relevant partonic subprocess under consideration. so, the direct photon contribution to the differential cross section of γp → bb̄ + x process is given by dσ(dir)(γp → bb̄ + x) dyb dp b t = ∫ |m̄| (γg∗ → bb̄) π(x s) ( − α ) a(x , k t ,µ )dk t dφ π dφb π , ( ) where |m̄| (γg∗ → bb̄) is the squared off-shell matrix element which depends on the trans- verse momentum k t , φ and φb are the azimuthal angles of the initial virtual gluon and the produced quark, respectively. the formula for the resolved photon contribution can be obtained by the similar way. but one should keep in mind that convolution in ( ) should be made also with the unintegrated gluon distribution aγ(x, k t ,µ ) in a photon. the final expression for the differential cross section has the form dσ(res)(γp → bb̄ + x) dyb dp b t = ∫ |m̄| (g∗g∗ → bb̄) π(x x s) × ×aγ (x , k t ,µ )a(x , k t ,µ )dk t dk t dyb̄ dφ π dφ π dφb π , ( ) where φ is the azimuthal angle of the initial virtual gluon having fraction x of a ini- tial photon longitudinal momentum. it is important that squared off-shell matrix element |m̄| (g∗g∗ → bb̄) depends on the both transverse momenta k t and k t . the analytic ex- pressions for the |m̄| (γg∗ → bb̄) and |m̄| (g∗g∗ → bb̄) have been evaluated in our previous papers [ , ]. note that if we average ( ) and ( ) over k t and k t and take the limit k t → and k t → , then we obtain well-known formulas corresponding to the leading- order (lo) qcd calculations. the recent experimental data [ – ] taken by the h and zeus collaborations refer to the b-quark photoproduction in ep collisions, where electron is scattered at small angle and the mediating photon is almost real (q ∼ ). therefore γp cross sections ( ) and ( ) needs to be weighted with the photon flux in the electron: dσ(ep → bb̄ + x) = ∫ fγ/e(y)dydσ(γp → bb̄ + x), ( ) where y is a fraction of the initial electron energy taken by the photon in the laboratory frame, and we use the weizacker-williams approximation for the bremsstrahlung photon distribution from an electron: fγ/e(y) = αem π ( + ( − y) y ln q max q min + m ey ( q max − q min )) . ( ) here αem is sommerfeld’s fine structure constant, me is the electron mass, q min = m ey /( − y) and q max = gev , which is a typical value for the recent photoproduction measure- ments at hera. the multidimensional integration in ( ), ( ) and ( ) has been performed by means of the monte carlo technique, using the routine vegas [ ]. the full c++ code is available from the authors on request . this code is practically identical to that used in [ ], with exception that now we apply it to calculate beauty production instead charm. numerical results we now are in a position to present our numerical results. first we describe our theoret- ical input and the kinematical conditions. lipatov@theory.sinp.msu.ru . theoretical uncertainties there are several parameters which determined the normalization factor of the cross sections ( ) and ( ): the beauty mass mb, the factorization and normalisation scales µf and µr and the unintegrated gluon distributions in a proton a(x, k t ,µ ) and in a photon aγ(x, k t ,µ ). concerning the unintegrated gluon densities in a proton, in the numerical calculations we used five different sets of them, namely the j (set — ) [ ], kms [ ] and kmr [ ]. all these distributions are widely discussed in the literature (see, for example, review [ , ] for more information). here we only shortly discuss their characteristic properties. first, three sets of the j gluon density have been obtained [ ] from the numerical solution of the full ccfm equation. the input parameters were fitted to describe the proton structure function f (x,q ). note that the j set and j set densities contain only singular terms in the ccfm splitting function pgg(z). the j set gluon density takes into account the additional non-singlular terms . these distributions have been applied in the analysis of the forward jet production at hera and charm and bottom production at tevatron [ ] (in the framework of monte-carlo generator cascade) and have been used also in our calculations [ ]. another set (the kms) [ ] was obtained from a unified bfkl-dglap description of f (x,q ) data and includes the so-called consistency constraint [ ]. the consistency constraint introduces a large correction to the lo bfkl equation. it was argued [ ] that about % of the full nlo corrections to the bfkl exponent ∆ are effectively included in this constraint. the kms gluon density is successful in description of the beauty production at tevatron [ , ] and j/ψ meson photo- and leptoproduction at hera [ , ]. the last, fifth unintegrated gluon distribution a(x, k t ,µ ) used here (the so-called kmr distribution) is the one which was originally proposed in [ ]. the kmr approach is the formalism to construct unintegrated gluon distribution from the known conventional parton (quark and gluon) densities. it accounts for the angular-ordering (which comes from the coherence effects in gluon emission) as well as the main part of the collinear higher-order qcd corrections. the key observation here is that the µ dependence of the unintegrated parton distribution enters at the last step of the evolution, and therefore single scale evolution equations (dglap or unified bfkl-dglap) can be used up to this step. also it was shown [ ] that the unintegrated distributions obtained via unified bfkl-dglap evolution are rather similar to those based on the pure dglap equations. it is because the imposition of the angular ordering constraint is more important [ ] than including the bfkl effects. based on this point, in our further calculations we use much more simpler dglap equation up to the last evolution step . note that the kmr parton densities in a proton were used, in particular, to describe the prompt photon photo- and hadroproduction at hera [ ] and tevatron [ , ]. in the case of a real photon, we have tested two different sets of the unintegrated gluon densities aγ(x, k t ,µ ). first of them was obtained [ ] from the numerical solution of the full ccfm equation (which has been also formulated for the photon). here we will use this gluon density together with the three sets of the j distribution when calculating the see ref. [ ] for more details. we have used the standard grv (lo) parametrizations [ ] of the collinear quark and gluon densities. resolved photon contribution ( ). also in order to obtain the unintegrated gluon density in a photon we will apply the kmr method to the standard grv parton distributions [ ]. in the numerical calculations we will use it together with the kmr distributions in a proton. note that both gluon densities aγ(x, k t ,µ ) discussed here have been already applied in the analysis of the heavy (charm and beauty) quark [ – ] and j/ψ meson [ , ] production in γγ collisions at lep . we would like to point out that at present there is not the unintegrated gluon distribution corresponding to the unified bfkl-dglap evolution in a photon. therefore we will not take into account the resolved photon contribution ( ) in the case of kms gluon. also the significant theoretical uncertainties in our results connect with the choice of the factorization and renormalization scales. first of them is related to the evolution of the gluon distributions, the other is responsible for the strong coupling constant αs(µ r). the optimal values of these scales are such that the contribution of higher orders in the perturbative expansion is minimal. as it often done [ , – , ] for beauty production, we choose the renormalization and factorization scales to be equal: µr = µf = µ = √ m b + 〈p t 〉, where 〈p t 〉 is set to the average p t of the beauty quark and antiquark . note that in the present paper we concentrate mostly on the non-collinear gluon evolution in the proton and do not study the scale dependence of our results. to completeness, we take the b-quark mass mb = . gev and use lo formula for the coupling constant αs(µ ) with nf = active quark flavours at Λqcd = mev, such that αs(m z ) = . . . inclusive beauty photoproduction the recent experimental data [ – ] for the inclusive beauty photoproduction at hera comes from both the h and zeus collaborations. the b-quark total cross section for pt > p min t as well as the beauty transverse momentum distribution have been determined. the zeus data [ , ] refer to the kinematical region defined by |ηb| < and q < gev , where ηb is the beauty pseudo-rapidity. the fraction y of the electron energy transferred to the photon is restricted to the range . < y < . . in figs. and we show our predictions in comparison to the zeus data [ , ]. the solid, dashed, dash-dotted, dotted and short dash-dotted curves correspond to the results obtained with the j set — , kmr and kms unintegrated gluon densities, respec- tively. one can see that overall agreement between our predictions and experimental data is a very good. all three sets of the j distribution as well as the kms gluon density give results which are rather close to each other (except large pbt region where the kms density predicts more hard behaviour). we find also a some enhancement of the estimated cross sections as compared with the collinear nlo qcd calculations which lie somewhat below the measurements but still agree with the data within the scale uncertainties. this enhance- ment comes, in particular, from the non-zero transverse momentum of the incoming off-shell gluons. note that the kmr gluon distribution gives results which lie below the zeus data and which are very similar to the nlo qcd predictions. this observation coincides with we use special choice µ = k t in the case of kms gluon, as it was originally proposed in [ ]. here and in the following all kinematic quantities are given in the laboratory frame where positive oz axis direction is given by the proton beam. source σ(ep → e′bb̄ + x) [nb] h measurement [ ] . ± . (stat.) + . − . (sys.) cascade [ ] . + . − . j set . j set . j set . kmr . kms . table : the total cross section of the inclusive beauty photoproduction in electron-proton collisions at q < gev . the ones [ ]. such underestimation can be explained by the fact that leading logarithmic terms proprtional to ln /x are not included into the kmr formalism. also the total inclusive beauty cross section σ(ep → ebb̄ + x) has been measured [ ] by the h collaboration and it was found to be equal to . ± . (stat.) + . − . (sys.) nb for q < gev . the collinear nlo qcd calculations predict a cross section which is about a factor of below the h measurements [ ]. the results of our calculations supplemented with the different unintegrated gluon densities are collected in table . also the predictions of the monte-carlo generator cascade [ ] are shown for comparison. one can see that earlier h data [ ] exceed our theoretical estimations by a factor about . however, recent analysis which has been performed in [ , ] does not confirm the results of the first measurements [ ]. so, the cross section for muon coming from b decays in dijet photoproduction events was found [ ] to be significantly lower than one reported in [ ]. therefore we can expect that the inclusive b-quark cross section (which can be obtained after extrapolation of dijet and muon cross section to the full phase space) will be reduced and agreement with our predictions will be significantly improved. in general, we can conclude that the cross sections of inclusive beauty photoproduc- tion calculated in the kt -factorization formalism (supplemented with the ccfm or unified bfkl-dglap evolution) are larger by − % than ones calculated at nlo level of collinear qcd. our results for the total and differential cross sections are in a better agree- ment with the h and zeus data than the nlo qcd predictions. we find also that the individual contributions from the photon-gluon and gluon-gluon fusion to the inclusive b- quark cross section in the kt -factorization approach is about and %, respectively. this is in agreement with the results presented in [ ] where the kmr and gbw unintegrated gluon densities has been used. . dijet associated beauty photoproduction now we demonstrate how the kt -factorization approach can be used to calculate the semi-inclusive beauty photoproduction rates. the basic photon-gluon or gluon-gluon fusion subprocesses give rise to two high-energy b-quarks, which can further evolve into hadron jets. in our calculations the produced quarks (with their known kinematical parameters) were taken to play the role of the final jets. these two quarks are accompanied by a number of gluons radiated in the course of the gluon evolution. as it has been noted in [ ], on the average the gluon transverse momentum decreases from the hard interaction block towards the proton. we assume that the gluon emitted in the last evolution step and having the four-momenta k′ compensates the whole transverse momentum of the gluon participating in the hard subprocess, i.e. k′t ≃ −kt . all the other emitted gluons are collected together in the proton remnant, which is assumed to carry only a negligible transverse momentum compared to k′t . this gluon gives rise to a final hadron jet with e jet t = |k′t | in addition to the jet produced in the hard subprocess. from these three hadron jets we choose the two ones carrying the largest transverse energies, and then compute the beauty and associated dijet photoproduction rates. the recent experimental data [ , ] on the beauty and associated dijet production at hera come from both h and zeus collaborations. the zeus data [ ] refer to the kinematical region defined by . < y < . , q < gev and given for jets with p jet t > gev, p jet t > gev and |ηjet| < . . the measured cross sections have been presented for muons coming from semileptonic b decays in dijet events with p µ t > . gev and − . < ηµ < . . the more recent h data [ ] refer to the same kinematical region except another muon pseudo-rapidity requirement: − . < ηµ < . . to produce muons from b-quarks in our theoretical calculations, we first convert b-quarks into b-hadrons using the peterson fragmentation function [ ] and then simulate their semileptonic decay according to the standard electroweak theory . our default set of the fragmentation parameter is ǫb = . . so, the transverse momentum and pseudo-rapidity distributions of the b-quark decay muon for different kinematical region are shown in figs. — in comparison to the hera data. one can see that calculated cross sections (using the j and kms unintegrated gluon densities) agree very well with the experimental data except the low p µ t region (p µ t < gev) in fig. . note, however, that the behaviour of measured cross sections in this region is very different from each other in the h and zeus data. the p µ t distribution measured [ ] by the h collaboration falls steeply with increasing transverse momentum p µ t . the similar situation is observed also for the cross section measured as a function of the transverse momentum of leading jet p jet t (see fig. ). our calculations give a less steep behaviour and are lower than the h data in the lowest momentum bin by a factor of . . but at higher transverse momenta p µ t better agreement is obtained. note that in the case of p jet t distribution the discrepancy at low p jet t is smaller, is about . times only. in contrast, a good description of the zeus data [ ] (both in normalization and shape) for all values of p µ t is observed (see fig. ). therefore there is some inconsistency between the data. also the zeus collaboration have presented the data on the transverse momentum and pseudo-rapidity distributions of the jets associated with the muon (so-called µ-jet) or b- hadron (b-jet). these jets reproduce the kinematic of the b (or b̄) quark in a good ap- proximation. the µ-jet is defined as the jet containing the b-hadron that decays into the muon. similarly, the b-jet is defined as the jet containing the b (or b̄) hadron. in figs. — we show our predictions for the transverse momentum and pseudo-rapidity distribu- tions of the µ-jet and b-jet in comparison to the zeus measurements [ ]. one can see that note that such assumption is also used in the kmr formalism. of course, the muon transverse momenta spectra are sensitive to the fragmentation functions. however, this dependence is expected to be small as compared with the uncertainties coming from the unintegrated gluon densities in a proton and in a photon. j and kms gluon densities give results which agree well with the data, although slightly overestimate the data at low p µ−jet t (see fig. ). we would like to note that the kms gluon provides a more hard transverse momentum distribution of the final muon (or jets) as compared with other unintegrated densities under consideration. similar effect we have observed in the case of the inclusive beauty photopro- duction (in a previous section). another interesting observation is that the dotted curves which obtained using the kmr unintegrated gluon lie below the h and zeus data every- where. this fact confirms the assumption which was made in [ ] that the kmr formalism results in some underestimation of the calculated cross sections. also it is interesting that the difference in normalization between the kms and j predictions is rather small, is about % only. however, it is in the contrast with the d∗ and dijet associated photoproduc- tion at hera which has been investigated in our previous paper [ ], where we have found a relative large enhancement of the cross sections calculated using the kms gluon density. the possible explanation of this fact is that the large b-quark or j/ψ meson mass (which provide a hard scale) make predictions of the perturbation theory of qcd more applicable. next we concentrate on the very interesting subject of study which is connected with the individual contributions from the direct and resolved photon mechanisms to the cross section in the kt -factorization approach. as it was already mentioned above, the x obs γ variable (which corresponds at leading order to the fraction of the exchanged photon momentum in the hard scattering process) provides a tool to investigate the relative importance of different contributions. in lo approximation, direct photon events at parton level have xobsγ ∼ , while the resolved photon events populate the low values of xobsγ . the same situation is observed in a nlo calculations, because in the three parton final state any of these partons are allowed to take any kinematically accessible value. in the kt -factorization formalism the hardest transverse momentum parton emission can be anywhere in the evolution chain, and does not need to be closest to the photon as required by the strong µ ordering in dglap. thus, if the two hardest jets are produced by the bb̄ pair, then xobsγ is close to unity, but if a gluon from the initial cascade and one of the final b-quarks form the two hardest transverse momentum jets, then xobsγ < . this statement is clearly demonstrated in fig. where separately shown the contributions from the photon-gluon (dashed curve) and gluon-gluon fusion (dash-dotted curve) subprocesses. the solid curve represents the sum of both these contributions. we have used here the kmr unintegrated gluon density for illustration. as it was expected, the gluon-gluon fusion events (with a gluon coming from the photon) are distributed over the whole xobsγ range. it is clear that these events play important role at small values of xobsγ . next, in agreement with the expectation for direct photon processes, the peak at high values of the xobsγ is observed. however, one can see that off-shell photon-gluon fusion results also in substantial tail at small values of xobsγ . the existence of this plateau in the collinear approximation of qcd usually is attributted to the heavy quark excitation from resolved photon. in the kt -factorization approach such plateau indicates the fact that the gluon radiated from evolution cascade appears to be harder than b-quarks (produced in hard parton interaction) in a significant fraction of events [ – ]. in fig. and we confront the xobsγ distributions calculated in different kinematical regions with the hera data [ , ]. one can see that the j and kmr unintegrated gluon densities give a reasonable description of the data but tend to slightly underestimate them at middle and low xobsγ . in the case of kms gluon this discrepancy is more significant source σ(ep → ebb̄ + x → ejjµ + x′) [pb] h measurement [ ] . ± . (stat.) ± . (sys.) nlo qcd (fmnr) [ ] . + . − . cascade (j set ) . pythia [ ] . j set . j set . j set . kmr . kms . kms (mb = . gev, Λqcd = mev) . table : the total cross section of the beauty and associated dijet photoproduction obtained in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . since the contribution from the gluon-gluon fusion subprocess are not taken into account here. the monte-carlo generator cascade [ ] (which generates low xobsγ events via initial state gluon radiation without using a gluon density in a photon) also underestimate [ ] the cross sections at low xobsγ . note that the shapes of x obs γ distributions predicted by the j and kmr densities differs from each other. this fact is connected with different properties of corresponding unintegrated gluon distributions in a proton and in a photon. in general, from fig. — we can conclude that the gluon-gluon fusion contribution is important in description of the experimental data and that the behaviour of calculated xobsγ distributions at low values of xobsγ is strongly depends on the unintegrated gluon densities used. however, our calculations still reasonable agree with the h and zeus data within the theoretical and experimental uncertainties. now we turn to the total cross section of b-quark and associated dijet photoproduction. the zeus collaboration has presented [ ] the results for forward, barrel and rear muon- chambers regions which defined by − . < ηµ < − . , pµt > . gev (rear), − . < ηµ < . , p µ t > . gev (barrel) and . < η µ < . , p µ t > . gev, p µ > gev (forward). in fig. we display the results of our calculations in comparison to the recent zeus data. one can see that our predictions (supplemented with the j and kms gluon densities) agree well with the measurements in the barrel region but underestimate the data in rear and forward ones. the main discrepancy is found in forward kinematical region where our predictions are below the data by a factor of . . in table we compare the calculated cross section with the h data [ ] which has been obtained in another kinematical region (defined above). the predictions of monte-carlo programs pythia [ ], cascade [ ] as well as nlo qcd calculations (fmnr) [ ] are also shown for comparison. note that these results are in a good agreement with each other but are about . standard deviations below [ ] the data. our predictions are somewhat higher but still lie below the data, too. however, this discrepancy is not dramatic, because some reasonable variations in beauty mass mb, energy scale µ or Λqcd parameter, namely . < mb < gev, µ / < µ < µ (where µ is the transverse mass of produced b-quark) and < Λqcd < mev, can completely eliminate the visible disagreement. to be precise, we have repeated our calculations using the kms gluon density with the mb = . gev and Λqcd = mev. we obtained the value σ = . pb which is close to the experimental data point σ = . ± . ± . pb. finally, we would like to note that in according to the analysis [ , ] which was done by the h and zeus collaborations, in order to obtain a realistic comparison of the data and nlo qcd calculations the corrections for hadronisation should be taken into account in the predictions. the correction factors are typically . − . depending on a bin [ , ]. these factors are not accounted for in our analysis. conclusions we have investigated the beauty production in electron-proton collisions at hera in the kt -factorization qcd approach. the different photoproduction rates (both inclusive and associated with hadronic jets) have been studied. we took into account both the direct and resolved photon contribution. in numerical analysis we have used the unintegrated gluon densities which are obtained from the full ccfm, from unified bfkl-dglap evolution equations (kms) as well as from the kimber-martin-ryskin prescription. our investiga- tions were based on lo off-mass shell matrix elements for the photon-gluon and gluon-gluon fusion subprocesses. special attention has been drawn to the xobsγ variable since this quantity is sensitive to relative contributions to the cross section from the different production mech- anisms. we demonstrate the importance of gluon-gluon fusion subprocess in description of the experimental data at low values of xobsγ . we have shown that the kt -factorization approach supplemented with the ccfm or bfkl-dglap evolved unintegrated gluon distributions (the j or kms densities) re- produces well the numerous hera data on beauty production. at the same time we have obtained that the kimber-martin-ryskin formalism results in some underestimation of the cross sections. this shows the importance of a detail understanding of the non-collinear parton evolution process. acknowledgements the authors are very grateful to s.p. baranov for encouraging interest and very helpful discussions, l.k. gladilin for reading of the manuscript and very useful remarks. this 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[ ] t. sjöstrand et al. comput. phys. comm. , ( ). http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ http://arxiv.org/abs/hep-ph/ σ (p t > p tm in ) ( n b ) pt min (gev) zeus - figure : the inclusive beauty cross section as a function of pmint calculated at |ηb| < , q < gev and . < y < . . the solid, dashed, dash-dotted, dotted and short dash-dotted curves correspond to the j set — , kmr and kms unintegrated gluon distributions, respectively. the experimental data are from zeus [ ]. figure : the differential cross section dσ/dpbt for the inclusive beauty production calculated at |ηb| < , q < gev and . < y < . . all curves are the same as in fig. . the experimental data are from zeus [ , ]. figure : the differential cross section dσ/dp µ t for dijets with an associated muon coming from b decays in the kinematic range − . < ηµ < . , q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the differential cross section dσ/dp µ t for dijets with an associated muon coming from b decays in the kinematic range − . < ηµ < . , q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from h [ ]. figure : the differential cross section dσ/dηµ for dijets with an associated muon coming from b decays in the kinematic range p µ t > . gev, q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the differential cross section dσ/dηµ for dijets with an associated muon coming from b decays in the kinematic range p µ t > . gev, q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from h [ ]. figure : the leading jet transverse momentum distribution dσ/dp jet t for dijets with an associated muon coming from b decays in the kinematic range − . < ηµ < . , q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves here are the same as in fig. . the experimental data are from h [ ]. figure : the transverse momentum distribution of the jet associated to the muon coming from b decays in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . and |ηµ−jet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the pseudo-rapidity distribution of the jet associated to the muon coming from b decays in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . and p µ−jet t > gev. all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the transverse momentum distribution of the jet containing a b-hadron in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . and |ηb−jet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the pseudo-rapidity distribution of the jet containing a b-hadron in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . and |ηb−jet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the differential cross section dσ/dxobsγ for dijets with an associated muon coming from b decays in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . separately shown the contributions from the photon-gluon (dashed curve) and gluon-gluon fusion (dash-dotted curve). solid curve represents the sum of both these contributions. the kmr unintegrated gluon densities in a proton and in a photon has been used. figure : the differential cross section dσ/dxobsγ for dijets with an associated muon coming from b decays in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. figure : the differential cross section dσ/dxobsγ for dijets with an associated muon coming from b decays in the kinematic range − . < ηµ < . , pµt > . gev, q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from h [ ]. figure : the cross section for muon coming from b decays in dijet events calculated in the rear, barrel and forward kinematical regions (see text). the cuts are applied: q < gev , . < y < . , p jet t > gev, p jet t > gev and |ηjet| < . . all curves are the same as in fig. . the experimental data are from zeus [ ]. introduction basic formulas kinematics cross section for beauty photoproduction numerical results theoretical uncertainties inclusive beauty photoproduction dijet associated beauty photoproduction conclusions acknowledgements the offence of beauty in modern western art music religions , , – ; doi: . /rel religions issn - www.mdpi.com/journal/religions article the offence of beauty in modern western art music peter bannister rue deparcieux, paris f- , france; e-mail: apbannist@aol.com; tel.: + - - - received: october ; in revised form: december / accepted: december / published: december abstract: in recent decades, beauty has become a largely unfashionable, even offensive notion within art and philosophy. as eastern orthodox theologian, david bentley hart, has pointed out, this offence has a twofold sense. firstly, the ‘beautiful’ has been dismissed as philosophically insignificant in comparison to the ‘sublime’ by an intellectual tradition tracing itself back to immanuel kant’s critique of judgment. secondly, the making of apparently beautiful art has, especially after the shoah, frequently been regarded as ethically offensive in the face of suffering in the world. the present essay discusses how these two critiques of the beautiful find themselves reflected in twentieth and twenty-first century musical aesthetics, with particular reference to the writings of theodor w. adorno, and asks what solutions have been found by composers of christian sacred music in the western tradition confronted by this ‘taboo on beauty’. keywords: beauty; atonality; david hart; adorno; leibowitz; messiaen . introduction: the end of aesthetics? both in philosophy and in art, beauty, it would seem, is out of fashion. indeed not only out of fashion but downright offensive to the contemporary western mind. this seemingly strange observation is one of the main starting-points for eastern orthodox theologian, david bentley hart, in the beauty of the infinite, a thought-provoking and virtuosic exploration of the aesthetic dimension of christian truth which has lost none of its force or relevance a decade after its publication in . a scouring of the philosophical landscape leads hart to contend that the beauty of the world of sensory phenomena is predominantly treated with contemptuous dismissal in an age characterized by radically anti-metaphysical “narratives of the sublime”, effectively demolished as a category worthy of serious thought. this, he asserts, reflects a philosophical tradition traceable back to the enlightenment: open access religions , ‘as it happens, beauty has fallen into considerable disfavor in modern philosophical discourse, having all but disappeared as a term in philosophical aesthetics. in part this is attributable to the eighteenth-century infatuation with longinus’s distinction between the beautiful and the sublime, one of whose unfortunate effects was to reduce the scope of the beautiful to that of the pretty, the merely decorative, or the inoffensively pleasant; in the climate of postmodern thought, whose humors are congenial to the sublime but generally corrosive of the beautiful, beauty’s estate has diminished to one of mere negation, a spasm of illusory calm in the midst of being’s sublimity, its “infinite speed”’ ([ ], p. ). hart points out that the locus classicus of the divorce between the beautiful and the sublime is immanuel kant’s dissection of the experience of sublimity in his critique of judgement which sets the infinity of mental concepts over and against the finite reality of the phenomenal realm. the kantian sublime radically breaks with the latter: ‘unlike the beautiful, its manifestation is an intuition of the indeterminate, whether one encounters it in the incomprehensible vastitude of the “mathematical sublime” or in the incomprehensible natural power of the “dynamical sublime”, though, in fact, the true sublime properly resides nowhere in the things of sensibility (which can only suggest it), but only in the mind, which discovers, even in the instant of its rapture, its own essential superiority over all of nature.’ ([ ], p. ) for hart, this line of thought has acquired particular force in postmodern authors such as jean-françois lyotard, who sees kant as heralding ‘the end of an aesthetics, that of the beautiful, in the name of the final destination of the mind, which is freedom’([ ], p. , quoted in [ ], p. ). beauty is offensive to this philosophical current to the extent that it is at best an irrelevance, at worst an obstacle to reaching the philosopher’s ‘final destination’. going on to expose the essentially nihilistic, post-nietzschean character of this supposed freedom, hart’s beauty of the infinite makes an impassioned defence of the persuasive, rhetorical dimension of the christian message over against the postmodern refusal to countenance any kind of analogy between beauty, whether natural or artistic, and the infinitely beautiful creator. the second ‘offence of beauty’ is perhaps less central to hart’s overall argumentation, but is stated no less explicitly in his preliminary remarks: with its implicit promise of transcendent healing of the broken world, beauty is viewed as a suspicious distraction from the violence of experience which demands more than a purely aesthetic response: ‘the marmorean repose of a child lately dead of meningitis might present a strikingly piquant tableau; cambodian killing fields were often lushly flowered [...] beauty seems to promise a reconciliation beyond the contradictions of the moment, one that perhaps places time’s tragedies within a broader perspective of harmony and meaning, a balance between light and darkness; beauty appears to absolve being of its violences’ ([ ], p. ). building in the remainder of the present essay on these perceptive remarks of hart’s, i would like to discuss how these two objections levelled against beauty by philosophy (and ethics) find themselves reflected in western art-music in the late twentieth century (and perhaps to a lesser extent on into the twenty-first). religions , . abstraction and rationalization it might be argued that with the breakdown from just after onwards of the system of tonality which had held sway since the time of j.s. bach, much modern music consciously broke loose from its traditional moorings in an unprecedented fashion. this is especially noticeable in radical works (by composers such as pierre boulez or karlheinz stockhausen) written in the decades immediately following the end of world war ii. avant-garde music distanced itself from its social roots by waging war on received notions of melody, tonal/modal harmony and musical phrasing or syntactical organization, thereby opposing analogies with song and language. indeed, atonal music at its most uncompromising arguably goes further in also freeing itself via radical abstraction from the shackles of sensory perception, from the need to be comprehensible as an aural experience. instead, aided by rationalizing mathematics, it strives for the freedom of lyotard’s “final destination of the mind”, thus siding with the sublime against the sensorially beautiful in terms of the kantian polarity discussed by david bentley hart. with the abolition of all external referents, we have the logical end-point of the tradition of ‘absolute music’ beginning with beethoven and strikingly contemporaneous with german philosophical idealism, (as musicologist daniel chua has pointed out at length in his highly insightful and entertaining study entitled absolute music and the construction of meaning [ ]. take for example the following very ambitious declaration dating from penned by france’s leading apostle of twelve-tone music, the composer and conductor rené leibowitz, which i quote in order to give a taste of the sort of equation between music and philosophy which became prevalent in the post-war years. in case anyone thinks this kind of theorizing is, to quote one leading british music historian, nothing but ‘pretentious goobledegook’ [ ], it is worth pointing out that leibowitz’s seminal introduction à la musique de douze sons was written in direct collaboration with none other than jean-paul sartre. focussing on the break with tonality in the works of arnold schoenberg, he claims that the modern composer effectively starts from zero, music being an expression of pure consciousness unaffected by any tonal system floating in the background and dictating the way in which elements of the music are shaped: ‘in discarding the tonal system, schoenberg to some extent places himself outside any pre-established musical contingency […] such an attitude of putting the musical world ‘ in parentheses’ effectively corresponds to the act of phenomenological reduction as understood by husserl […] for the twelve-tone composer there can be no question of an essence preceding existence; on the contrary, it is the object in existence [l’existant], entirely recreated with each new compositional effort, which constitutes its own essence as well as its own laws’ ([ ], pp. – ). music is by its very nature maybe the most ‘abstract’ of the arts; the radicalization of such abstraction in instrumental music after —overtly associated by leibowitz and sartre with existentialism—is a complex phenomenon. the implications of abstract art perhaps merit more attention than they have hitherto received on the part of theologians reading modernism's vision of the artistic endeavour as a ‘sign of the times’, in terms of the perception of the artist no longer as a craftsman working with the material world of sound, but as a creator ex nihilo. as rowan williams points out in his compelling grace and necessity [ ], these implications were already intuited some decades earlier in the thomist aesthetics of jacques maritain. see for example maritain’s discussion of the difference religions , . adorno and the taboo on musical beauty as for the second objection to the musically ‘beautiful’—that of its falsehood in a world deprived of beauty, the key philosophical reference-point is the highly influential writings of theodor wiesengrund adorno in relationship to the crisis of musical form after . in the frequently polemical discussions concerning musical composition in the second half of the twentieth century, few names continue to arouse fiercer passions than that of adorno, whether championed as the prophet of the avant-garde or reviled as an intolerant elitist guilty of a form of cultural terrorism, a misanthrope whose forbidding rhetoric succeeded in crippling music after world war ii, ‘a kind of inverse cassandra, fated to tell untruths but to be believed’ [ ]. his two-part philosophy of new music [ ], perhaps the best-known articulation of adorno’s stern dialectical vision in which the essay schoenberg and progress has as its counterfoil stravinsky and the restoration, continues to polarize opinion years after its publication and to function as a seemingly inescapable starting-point for any serious debate on musical modernism . it is certainly the foundational text for a view of artistic progress as a ‘canon of prohibitions’ ([ ], p. ), translated by the post-war generation of composers into a radical rupture with all past musical idioms. famously epitomized by the statement of the young pierre boulez that composers who did not follow down schoenberg’s dodecaphonic road were “useless”, post-serialism became the official idiom of the western european avant-garde as typified by institutions such as the darmstadt international summer courses for new music, where adorno was a lecturer. basing its interpretation on an immanent method of criticism, schoenberg and progress focuses on the development of musical material as ‘sedimented spirit, preformed socially by human consciousness’ ([ ], p. ), mirroring the historical process. in the grim context of , the latter had in adorno’s view had reached the point at which market forces on one hand and totalitarian repression on the other had effectively liquidated even the concept of the autonomous subject. given this bleak reality of utter alienation, adorno asserts the bankruptcy of all artistic images of harmony (on which the tonal system is predicated) as ‘unsustainable in the face of the catastrophe toward which reality is veering’ ([ ], p. ). this goes far deeper than mere issues of style: for adorno the whole notion of between the divine and the human creative process in the frontiers of poetry dating from [ ]. describing the search for abstract art with particular reference to tendencies within french artistic life after mallarmé, he asserts that “to order contemporary art to exist as abstract art, discarding every condition determining its existence in the human subject, is to have it arrogate to itself the aseity [being un-derived] of god”. ([ ], p. ). at the same time maritain does not argue in favour of a utilitarian or merely representational view of art, recognizing that “art itself [...] is in a way an inhuman virtue, a straining after a gratuitously creative activity, entirely absorbed in its mystery and its own laws of operation, refusing to subordinate itself either to the interests of men or to the evocation of what already exists. in short, the straining towards abstract act follows from the very essence of art, once beauty has awakened it to self-consciousness.” ([ ], p. ). although maritain’s thought and its place within the catholic intellectual revival in france in the early twentieth century has lately been the object of excellent historical analysis on the part of jesuit polymath stephen schloesser in his landmark study jazz age catholicism [ ], maritain remains a largely neglected resource for contemporary reflection on artistic practice. adorno’s philosophy of new music is maybe even more frequently cited by writers sceptical of the project of the avant-garde than by its supporters: for two recent french examples see the discussions of adorno in benoît duteurtre’s requiem pour une avant-garde [ ] or composer nicolas bacri’s notes étrangères: considérations paradoxales sur la musique d’aujourd’hui [ ]. religions , finished aesthetic form itself becomes untenable, as in the face of unspeakable human suffering artistic form as a structural image of reconciliation can only be equated with false consciousness, a weapon in the hands of the oppressors. for adorno, radical negation is the only path left open: he chillingly concludes that all music’s ‘happiness is in the knowledge of unhappiness; all its beauty is in the denial of the semblance of the beautiful’ ([ ], p. ). this is of course an unremittingly pessimistic outlook, in that adorno is under no illusion that such art can be “successful” either in terms of securing an audience or even in creating coherent artworks. despite the title of the first essay of the philosophy of new music, “schoenberg and progress”, to read adorno as sanctioning the twelve-tone system of composition as the progressive method on which the future of music could be positively constructed is to misunderstand his dialectic. although he became the uncontested principal theoretical reference of the avant-garde, he was simultaneously the first serious commentator to note the self-defeating tendency within the dodecaphonic compositional method. on one level, twelve-tone music represents total rational domination of the musical material, as the integrally organized work consumes everything via the row (the series of all twelve chromatic pitches) as grundgestalt: ‘twelve-tone technique approaches the ideal of mastery as domination, whose boundlessness consists in the exclusion of whatever is heteronomous, of whatever is not integrated into the continuum of this technique’ ([ ], p. ). paradoxically, the effect of this ‘mastery’ is not the liberation of the composer as was promised by the break with tonality (seen as ‘emancipation of the dissonance’). while adorno clearly sees the expressionistic period of ‘heroic’ free atonal works (roughly – ) in schoenberg’s output as the pinnacle of his achievement, the systematic serialism which evolves from free atonality strangely leads not to increased freedom but to its opposite. with the abolition of any grammar of hierarchical relations between notes (in, for example, a chord), harmonic differentiation, the guiding principle behind the whole germanic musical tradition dating back to bach, becomes impossible and with it meaningful formal articulation in time and indeed expression itself. in striving for ultimate mastery, the composer as autonomous subject effectively relinquishes all power to shape the music, which is now completely opaque, alienated. all that is left is the basic arithmetic of the method, ‘a machine that fulfills no function: it simply stands there, an allegory of the ‘technical age’. yet, via a dialectical sleight of hand of the type for which adorno is (in)famous, it is precisely this failure to communicate which for him constitutes the ‘truth-content’ of new music as it reveals the nature of historical reality itself, embracing aesthetic martyrdom in the process: ‘today the alienation inherent in the consistency of artistic technique itself forms the content of the artwork. the shocks of the incomprehensible—which artistic technique in the age of its meaninglessness dispenses—reverse. they illuminate the meaningless world. new music sacrifices itself to this. it has taken all the darkness and guilt of the world on itself.’ ([ ], p. ). the theological resonance of this final sentence is no accident; adorno’s thinking, like that of the frankfurt school in general, has powerful undercurrents of jewish messianism. charges of nihilism and here adorno’s thought strikingly parallels jacques ellul’s concept of modern western society as a totalizing système technique. of particular relevance is ellul’s penetrating analysis of art within a technological framework in l’empire du non-sens: l’art et la société technicienne [ ]. religions , misanthropy frequently levelled at adorno would be justified were it not for a highly individual form of negative theology in constant operation in his writing. although this is mostly implicit rather than overtly stated and easily missed given his prevalent tone of ‘protest atheism’, it surfaces most clearly in the closing passage of adorno’s minima moralia of : ‘the only philosophy which can be responsibly practised in the face of despair is the attempt to contemplate all things as they would present themselves from the standpoint of redemption. knowledge has no light but that shed on the world by redemption: all else is reconstruction, mere technique. perspectives must be fashioned that displace and estrange the world, reveal it to be, with its rifts and crevices, as indigent and distorted as it will appear one day in the messianic light’ ([ ], p. ). adorno’s work of the s can be read as a devastating critique of the failure of secular eschatologies of progress. the radically alienated artwork’s meaninglessness reveals the world's need for redemption, that future beauty whose cruel absence in the present art refuses to palliate. it is of course outside the scope of this article to chart the history of twentieth-century western art music, but the decades immediately following were marked by the emergence of an avant-garde dogma which effectively based itself on the argument of ‘historical necessity’ found in adorno’s philosophy of new music, but without its dialectical subtlety or an understanding of the via negativa this theme is profitably taken up in jürgen moltmann’s the coming of god [ ], where jewish thinkers are credited with an indispensable role in christian eschatology's proper reappraisal of jewish apocalyptic: ‘for the rebirth of messianic thinking out of the catastrophe of christian humanism in the first world war, we are indebted to martin buber, ernst bloch and franz rosenzweig, walter benjamin and theodor adorno [...] they brought reason into the jewish and christian hope and—even more important—hope into the reason that was self-sufficient and hence self-destroying. out of the ruins of historical rationality they rescued hope as a theological category. without their messianic thinking, eschatology today is literally unthinkable.’ ([ ], p. ). see also moltmann’s earlier discussion of adorno and horkheimer in the crucified god ([ ], pp. – ). john w. de gruchy and johann baptist metz are among other writers to have explored the theological potential in the work of the frankfurt school. this apophatic vision of course flies in the face of schoenberg’s own positive view of dodecaphonic technique as providing a unifying force for music endowed with the same level of structural power as tonality, a totalizing project which would assure german musical superiority for coming centuries. adorno’s analysis is underpinned by the belief that the immanent characteristics of artworks as objects take precedence over the intentions of their creators: he dismisses the naïve belief that an idiom historically derived from dissonance as the articulation of suffering or psychological collapse (as in a piece such as schoenberg’s erwartung) could somehow be translated into an affirmative system harnessed to technological progress, which he in any case views with extreme scepticism. this is highly ironic in that here he arguably anticipates the dead-end of a great deal of music written after , where the technique of the second viennese school, in itself intimately linked with and shaped by a certain philosophical and cultural central european climate) was adopted as an international “language” and therefore lay itself open to the criticism of reification as a mere self-legitimating style divorced from any deeper meaning, thereby degenerating into the antithesis of artistic freedom—conformism: ‘what the attentive ear discovered is distorted into a trumped-up system in which the criteria of compositional right and wrong are to be abstractly verified. this explains the readiness of so many young musicians—especially in the united states, where the sustaining experiences of twelve-tone technique are wanting—to write in the “twelve-tone system” and their elation at the invention of a surrogate for tonality, as if freedom were aesthetically intolerable and needed to be furtively replaced by a new compliancy’ ([ ], p. ). this is not altogether surprising given that adorno’s writing presupposes an acquaintance with the categories of german philosophical thought with which the majority of composers are unfamiliar (even pierre boulez has admitted that as a religions , behind it. music in the years after world war ii would seek theoretical legitimacy by reference to philosophy, science, architecture (e.g., xenakis) or even chance (john cage), but certainly not beauty. . sacred music and new tonality the position of overtly religious composers in relation to this modernistic taboo against beauty is a complex issue. naturally not all musical circles were equally affected by the debate, and tonal or modal music continued to be written for the church much as before by musicians who maintained their idiom unchanged. i have no wish whatsoever to belittle the contributions to the sacred musical repertoire of figures such as maurice duruflé, vaughan williams or herbert howells, all of whom produced substantial work after world war ii, but my own interest in the context of this essay is in those composers who attempted to engage with modernism in its radicality whilst continuing to write expressive sacred music, sharing rowan williams’s concern for ‘art which is intensely serious, unconsoling, and unafraid of the complexity of a world that the secularist too can recognize’. ([ ], p. ). as early as the end of the s, dissatisfaction with the postserial idiom had begun to set in within the avant-garde as composers such as györgy ligeti began to look for ways out of the aporia already indicated in the philosophy of new music, sensing that the strict application of twelve-tone technique had become a compositional straightjacket. on a technical level, experience led many to the conclusion that the possibilities of totally chromatic material had been exhausted and could only generate nondescript, identikit modernist musical objects, while philosophically it seems obvious that adorno’s call to artistic martyrdom through the embracing of a non-communicative language was an understandable response of self-immolation in the face of the extreme horror of the third reich and could never be translated into a general principle or long-term strategy. the next three decades were to see spectacular defections from the serialist camp as the desire both for beauty in a more positive sense and self-expression reasserted themselves. in the cases of arvo pärt, henryk mikołaj górecki and john taverner, all interestingly working independently of one another, the break with the dodecaphonic idiom went hand-in-hand with the development of a new type of sacred music sometimes referred to somewhat pejoratively as ‘holy minimalism’. other composers such as einojuhani rautavaara, alfred schnittke in his later years and (in my view somewhat more problematically) krzysztof penderecki sought to write in a more lyrical style with tonal elements. critical opinion remains divided as to the artistic quality and significance of what has been termed new tonality. consonance is certainly no longer an offence in the postmodern musical climate, but whether this in itself constitutes genuine beauty is another issue. for some, the return to diatonic material is a liberation which demonstrates that the project of the avant-garde was, to mis-appropriate an adornian phrase, ‘an experiment with a negative outcome’. others charge musical postmodernism with vacuity; the simple deployment of tonal chords, while not necessarily sounding ‘false’ as adorno claimed in , does not necessarily guarantee any sort of ‘truth-content’ or, to put it less polemically, carry any real artistic conviction. according to this viewpoint, which essentially repeats the critique of young man with limited philosophical baggage he felt intimidated by adorno). for a clear and penetrating discussion of the central adornian issues concerning music, see max paddison’s adorno’s aesthetics of music [ ]. a detailed but far more difficult exegesis of the philosophy of new music can be found in david roberts’ art and enlightenment: aesthetic theory after adorno [ ]. religions , neo-classicism found in the second part of the philosophy of new music entitled stravinsky and the restoration, tonality—like the bourgeois society which generated it—is irrevocably lost and all attempts to restore it doomed to failure. indeed, as with other art-forms, it seems that some postmodern composers, of whom gustav mahler was maybe the first in another age, anticipate this criticism by flaunting banality and meaninglessness as elements of style (though without mahler’s metaphysical nostalgia). it is hard to refute the suggestion that the scarring of humanity and our planet is such that beauty, for which tonal harmony is both a metaphor and a potential medium, cannot simply be taken for granted as artistic subject-matter; a true appreciation of the natural and human world is indissociable from a lament both over social injustice and the negative effect of post-enlightenment culture’s domination of nature. in this context it is worth emphasizing that the so-called “holy minimalists” all reverted to consonant music subsequent to a participation in the avant-garde, whether european (pärt, górecki, taverner) or in the american environment influenced by john cage. whether consciously or unconsciously, their music’s refusal to participate in the continuation of an essentially germanic artistic teleology would seem to endorse the adornian critique of the enlightenment as a dead end, while of course rejecting the hegelian conceptual apparatus on which that critique still relies. it would be a crude simplification to reduce the work of these composers to a common agenda, but they share a concern to obviate the pessimistic fin de partie (the reference to beckett is wholly intentional) of western art-music in its postserial form by a ressourcement that is either geographical (non-western elements in reich, johnson) and/or historical (the allusions to music pre-dating the enlightenment in pärt, gorecki and taverner). at the same time they resist the nihilism of the post-nietzschean, ‘anything goes’ variant of postmodernism, whose collages of universally available historical and stylistic idioms communicate “pure affirmation” without any attempt to construe meaning. minimalism constitutes one potent exit strategy from the crisis of musical modernism. its spiritual achievements of minimalism are considerable, examples being the shattering austerity of arvo pärt’s kanon pokojanen (liturgy of repentance, ), where radical musical simplicity and self-emptying penitence fuse to stunning effect, or the granitic beatus vir ( ) of górecki. the facile charge that the return to the simplest of tonal/modal means is an escapist abdication from contemporary social reality moreover ignores the fact that both composers just mentioned were actively involved in resistance to eastern bloc communism. just as ill-founded are the accusations of musical vacuity; given that many minimal works are overtly devotional in nature and are not conceived as exercises in the demonstration of technical ability for the benefit of music critics, the negative judgements emanating from some quarters of the musical establishment ought perhaps not to be surprising. indeed, the although their work does not feature so frequently in discussions of sacred music, here i would include steve reich and tom johnson, whose output includes the imposing and theologically engaged bonhoeffer oratorio ( – ) and the monumental zen-influenced cycle organ and silence ( ). górecki’s most successful work is arguably not the highly moving but somewhat one-dimensional third symphony (especially when to my taste spiritualized out of its rugged, earthbound context in the polished bestselling recording conducted by david zinman with dawn upshaw) but the wider-ranging “copernicus” symphony op. of a few years earlier which combines elements both of górecki’s modernist and minimalist periods. i doubt whether pärt, górecki or taverner would be unduly concerned at allegations of musical fideism; although i would not like to assert clear categorical boundaries in this respect, the primary aim of their works would appear to be worship rather than theological reflection or apologetics. religions , conscious ‘poverty’ of means employed may be seen as articulating an important message; minimalism's very strength would appear to derive from a radical paring down of the material and an implicit critique of the hubris of much of the western tradition’s search for subjective expression in art. the question nevertheless arises as to what other options may be open to judeo-christian composers in search of means of contemporary expression who wish to avoid an unreflecting conservatism while going beyond the effective but necessarily narrow focus of the minimalists? it is here that i would argue that the trajectory of olivier messiaen provides material for potentially fruitful reflection. . olivier messiaen olivier messiaen’s early style is one of the most immediately recognizable of any twentieth-century composer, not least because he himself was so explicit about its constituent elements. by the time of the publication of his technique de mon langage musical in , the compendium of his technical devices was already well-defined (his celebrated modes à transposition limitée, use of so-called hindu and greek rhythms...). messiaen had evolved a highly personal and controversial idiom which shocked some by its modernity, while offending others by its unabashed harmonic voluptuousness, the latter including the young pierre boulez, who famously described the first extracts from messiaen’s turangalîla-symphonie to be performed as ‘brothel music’ (musique de bordel) at their première in . although somewhat allergic to philosophical jargon and remote from the central european intellectual tradition both analyzed and personified by adorno, messiaen found himself at the centre of french post-war aesthetic debates both as a composer and a pedagogue. as a teacher at the paris conservatoire, his class became the spawning-ground for many of the leading avant-garde composers of the generation after , although messiaen himself taught analysis rather than composition and (unlike the highly partisan leibowitz) refrained from aligning himself with any movement. his own pieces from the years following the completion of turangalîla, certainly bear the marks of the aesthetic debates of the time. although nowhere in his pedagogical writings or commentaries on his own music is an overt adhesion to the ‘taboo on beauty’ to be found, it is striking that messiaen’s works from the period – (notably the quatre etudes de rhythme for piano and the two large organ works messe de la pentecôte and above all the livre d’orgue) see him move in the direction of increasing abstraction and intellectualization typical of the epoch. messiaen’s unashamed hallmark tonic and ‘added sixth’ chords of his music up until turangalîla, provocatively affirmative to the point of kitsch, are banished in favour of an austere linearity; although there is a subsequent loosening of this idiom in messiaen’s remaining works of the s, it is not until the mid- s (with et exspecto resurrectionem mortuorum and la transfiguration) that messiaen reintegrates certain elements of his luxuriant earlier style into his compositional language. curiously, jean boivin’s la classe de messiaen [ ] suggests that messiaen as a teacher was not untouched by the repressive attitude found in doctrinaire avant-garde circles towards melodic writing and ‘forbidden’ intervals (pointing out the appearance of octaves in his pupil’s compositions, for example, or advising his student akira tamba in that ‘there are currently two ways of approaching contemporary music: one must either go through twelve-tone technique or musique concrète, so choose’ ([ ], pp. – ). a charitable interpretation would be that messiaen’s comments reveal a realistic pedagogical concern for the acceptance of the younger composers’ work in a rigid musical climate, rather than a statement concerning the aesthetic validity of the styles in question. religions , there has been much speculation as to the reasons behind these stylistic shifts; less charitable critics have sometimes claimed that messiaen’s turn away from aural beauty to cerebral serial rigour was either a case of naïve pandering to fashion or a cynical act of self-preservation in the face of the dogmatic revolutionary zeal of his pupils. this interpretation is not as fanciful as it might seem: in comments of later years, messiaen distanced himself from twelve-tone works such as the modes de valeurs et d’intensités, which he came to regard as emotionally frigid intellectual exercises. there is for example a hint of earnestness as well as jest in his gently self-deprecating comments on the livre d’orgue, whose recourse to serialism he later described as ‘a sacrifice to the idols of the twentieth century’ ([ ], pp. – ). however, there is no doubting the seriousness of his engagement with the techniques of modernism; a balanced appreciation ought justly to emphasize both messiaen’s openness to new musical currents and his unrelenting desire to harness exploration to an underlying christian purpose which keeps his abstraction in check. even in the most dryly abstruse and least accessible passages of the livre d’orgue, he attempts to relate his chosen musical devices to theological concepts such as the ‘incomprehension surrounding the mystery of the holy trinity’ ([ ], p. ). moreover, he clearly and crucially maintains the dividing-line between the type of speculation invited by the imagery of the old testament prophets (as in ezekiel’s vision of les yeux dans les roues) and speculation for its own sake as a demonstration of the conceptual power of the human mind. messiaen is certainly attracted by the sublime, as for example indicated by the title of the rd movement of the livre d’orgue, les mains de l’abîme. his response to the abyss, however, is not that of kant’s critique: the overwhelming of the senses does not lead to an awareness of the conceptual superiority of the mind but to a sense of holy fear. the sublime and the beautiful are for messiaen not divorced but rather indissolubly linked, as a quotation of rilke’s st duino elegy in his compositional treatise makes clear in relation to his reading of the biblical prophets: ‘the beautiful is that degree of the awesome which we can still bear ... we can admire it, for it scorns to destroy us ... every angel is terrifying [...] the divine visions of the prophets have this terrifying beauty. terrifying, searing and at the same time pacifying. they leave us overwhelmed while communicating to us something of their peaceful force’ ([ ], p. ). equally central to messiaen’s thinking is the inseparability of artistic beauty and that of creation. for adorno any reference to the natural realm on the part of art had been essentially rendered impossible on account of the self-legitimating appeal to nature by totalitarianism (both in its fascist and socialist see peter bannister, ‘messiaen as preacher and evangelist in the context of european modernism.’ ([ ], pp. – ). translation and italicization (quote from rilke) mine. an awareness of this political background helps to understand the occasional excesses of adorno’s polemical style as exemplified by his seemingly unjustified and mis-directed tirade glosse über sibelius written for the zeitschrift für sozialforschung in . although it is difficult to detect any unsavoury political undertones in the admittedly nationalistic compositions of the by-then ageing finnish composer, it is not hard to see why the nazis would have been interested in co-opting his pantheistic symphonic music in the service of their own nordic pagan mythology. for adorno the link between nature-worship and fascist regression is explicit: ‘sibelius’s supporters scream in chorus: nature is all, nature is all. great pan, and where necessary blood and earth (blut und boden), step up into the picture.” an example of the avant-garde’s view of the illegitimacy of appeals to nature—and by implication the evocation of natural beauty—can be found in an article for die reihe, a journal associated with the darmstadt school, written by herbert eimert in : ‘in religions , realist variants); bolstered by an unshakable catholic theology and helped by geographical distance messiaen obviates this problem by ignoring the whole trajectory of the austro-german tradition and its concomitant view of music as the expression of subjectivity. this does not however mean that he seeks a return to the tonal system as objectively beautiful; the grammatical organization of tonality he (correctly) perceives as a social and historical construct that should not be preserved at all costs. instead, he anchors his music in two natural phenomena whose objectivity cannot be contested. the first is la résonance, i.e., the overtone series. this is part of creation and cannot be superseded by man-made strategies which ignore the physical properties of sound, its existence as aural reality. at a time when for many composers written notation of music had become a question of transcribing abstract thought, messiaen’s historical position is somewhat atypical in this regard. the second natural phenomenon is birdsong, which messiaen regards as ontologically prior to human music—it is ornithology which allows him, starting with a series of works in the s exclusively (and perhaps at first somewhat monotonously) based on birdsong, to avoid the aporia of the avant-garde and the whole issue of the crisis of subjective expression. messiaen’s language may not be to all tastes, but posterity would appear to have vindicated his aesthetic position: of all the major composers associated with the musical vanguard in western europe in the second half of the th century, messiaen is maybe the only one to have been able to appeal consciously to beauty with impunity. with the gradual thawing of the ideological climate from the s onwards—as the trauma of the experience of the second world war receded—it is understandable that several composers of messiaen’s generation (lutosławski and dutilleux being prime examples) should have moved towards greater lyricism in their later work. interestingly, for messiaen, unlike the somewhat younger ‘holy minimalists’, this does not represent a dialectical movement away from modernism and conditioned by it as its negative image. instead messiaen’s late masterpieces display an extremely individual combination of modernist techniques with the harmonic affirmation of his early works, a synthesis which arguably leads to some of messiaen’s greatest achievements such as the opera st françois d’assise. this inclusive attitude finds a parallel in his thomist standpoint on the relationship between space-time and eternity as articulated in in his commentary on the last of the trois petites liturgies (psalmodie de l’ubiquité par l’amour): ‘the words: ‘succession is simultaneity for you’ express ... the composer’s desire to escape time with its barriers and divisions’. the recent past, nothing was more in vogue than ‘nature’; not its secondary version, dominated by the supra-natural authority of the artist (as is sometimes understood in our milieu) but primal, pseudo-ontological nature decorated with orphism, where one finds grouped together the categories of race, people, blood and soil. this hijacking of nature is perhaps one of the reasons why art can no longer be brought back to nature. what despotism wants is not reason and order, but the “return to nature”, or, to speak like günther anders; “the little word nature is the one favoured by terror.” (cited esteban buch, figures politiques de la technique sérielle ([ ], pp. – . translation mine.) writing in the s in a far more genial tone than two decades earlier, adorno himself commented on the negative consequences of the “disempowerment of the living, listening act as the authentic constituent of music” ([ ], p. ). it is interesting to note that, writing in , antoine goléa—who was messiaen’s translator in darmstadt—interpreted the latter’s insistence on the superiority of natural to human music as an expression of pessimism concerning humanity stemming from the personal difficulties in messiaen’s life in the s, most notably the mental disintegration of his first wife claire delbos (see antoine goléa, rencontres avec olivier messiaen ([ ], pp. – ). in brigitte massin, olivier messiaen; une poétique du merveilleux ([ ], pp. – ). religions , messiaen’s thought is not dialectical but holistic. as all times (and places) are present to god, all possible epochs and styles are available as raw material to the composer, without exclusion. messiaen’s “theological rainbow” (arc-en-ciel théologique) seems to have a space for anything and everything from plainchant to einstein’s theory of relativity: for him there is no incompatibility between raiding the latest astronomical research as well as the neumes of ancient gregorian chant for inspiration. messiaen’s music, rooted in a positive eschatological vision of the new heavens and the new earth, remains teleological, but in a completely different sense both from that of the unthinking secular belief in progress and that of adorno’s dystopian vision. messiaen does not simply abandon modernism to its fate, but rather looks through and beyond it. . adorno or messiaen? for all the difficulties and limitations of his arguments, adorno’s consistent refusal to resolve dissonance prematurely (both in art and in thought itself) is surely a significant one for any attempt to hold artistic apophasis and cataphasis in proper tension. an understanding, though not necessarily an acceptance of the post-war taboo on beauty can help to bring christian artists back to a genuinely biblical vision in which concealment and revelation, cross and resurrection are inseparable. as he himself often admitted, olivier messiaen naturally tended towards being a ‘theologian of glory’. the titles of his early compositions such as l’apparition de l’eglise éternelle and l’ascension plainly bear this out. the ability to express a theologia crucis in music was one that messiaen had to learn and which went against his artistic grain. it was perhaps precisely by engaging, albeit idiosyncratically, with the negativity of the avant-garde and the sometimes barren asceticism of the s, allowing his language to be temporarily purged of the joyous sonorities and harmonic lushness of his earlier idiom, that messiaen was subsequently able to re-integrate both the timeless natural beauty of birdsong and the humanly conceived beauty of tonal harmony into an expanded idiom able to embrace the stigmata of st francis and the darkness of golgotha, employing the full panoply of techniques developed by modernism and somehow ‘evangelizing’ them. without wishing to make a qualitative comparison between styles, messiaen’s music at its best suggests that the drastic reduction of compositional means found in minimalism may not be the only way forward for the aspiring composer of sacred music for our times, and that something of the project of critics have not been slow to disqualify adorno’s musical aesthetics on the grounds of their over-reliance on a hegelian view of history and an ethnocentric refusal to acknowledge socio-historical contexts other than that of central europe (exemplified by his spectacular mistaken judgement on jazz). post-colonial theory in particular has exposed the element of domination in the adornian conceptual framework, somewhat ironically given that suspicion towards meta-narratives is one of the cornerstones of his project and one of its most successful aspects. this does not however in my view invalidate adorno’s analysis of his own tradition; nor should it be concluded that his method cannot necessarily be applied to other traditions given appropriate adaptation. an excellent if limited treatment of this aspect of messiaen’s output can be found in jean-françois labie’s le visage du christ dans la musique des xixe et xxe siècles [ ]. it is perhaps significant that the orchestral prelude to the section of st françois d’assise entitled les stigmates is a very rare instance in messiaen’s later works of the employment of total serialism to depict an atmosphere of anguish and foreboding. exemplified by the movement entitled les ténèbres from messiaen’s monumental cycle for organ livre du saint-sacrément, in which the composer unusually uses cluster techniques to convey the physical and spiritual darkness of the crucifixion. religions , modernity—indeed maybe a great deal—can still be redeemed once its undoubted technical discoveries are divested of their more dubious philosophical pretensions. to return to our starting-point, messiaen’s attempt to saving modernity from itself relies, at least in part, on insisting that the aural basis of music, its sensory beauty, is no mere epiphenomenon to be jettisoned in the quest for immaterial absolutes, but rather has value in and of itself, by virtue of its identity as part of divine creation. messiaen’s unfashionable emphasis on the significance of the beautiful in intimating divine transcendence suggests that the beautiful and the sublime should be viewed in a ‘both-and’ rather than an ‘either-or’ relationship. after all, it is worth recalling that the ultimate biblical promise is not merely the sublimity of a new heaven but also the imperishable beauty of a new earth (revelation ). conflicts of interest the author declares no conflict of interest. references . david bentley hart. the beauty of the infinite: the aesthetics of christian truth. grand rapids: eerdmans, , pp. , . . jean-françois lyotard. the inhuman. stanford: stanford university press, , p. . . daniel chua. absolute music and the construction of meaning. cambridge: cambridge university press, . . nigel simeone. “après la guerre.” the musical times , no. 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( ): – . . theodor adorno. philosophy of new music. translated, edited, and with an introduction by robert hullot-kentor. minneapolis: university of minnesota press, , pp. , , , , . . benoît duteurtre. requiem pour une avant-garde. paris: laffont, . . nicolas bacri. notes étrangères. anglet: atlantica/séguier, . . jacques ellul. l’empire du non-sens: l’art et la société technicienne. paris: presses universitaires de france, . . theodor adorno. minima moralia: reflections on a damaged life. translated by e.f.n. jephcott. london: new left books, , p. . . jürgen moltmann. the coming of god. translated by margareth kohl. minneapolis: fortress press, , p. . . jürgen moltmann. the crucified god. translated by r.a. wilson and john bowden. london: scm press, , pp. – . . max paddison. adorno’s aesthetics of music. cambridge: cambridge university press, . religions , . david roberts. art and enlightenment: aesthetic theory after adorno. lincoln: university of nebraska press, . . jean boivin. la classe de messiaen. paris: christian bourgois, , pp. – . . olivier messiaen. traité de rythme, de couleur, et d’ornithologie. paris: alphonse leduc, , vol. , pp. – , . . peter bannister. “messiaen as preacher and evangelist in the context of european modernism.” in messiaen the theologian. edited by andrew shenton. aldershot: ashgate, , pp. – . . esteban buch. “figures politiques de la technique sérielle.” in résistances et utopies sonores. edited by laurent feneyrou. paris: cdmc, , pp. – . . theodor adorno. “difficulties.” in essays on music: theodor w. adorno. selected, with introduction, commentary, and notes by richard leppert, new translations by susan h. gillespie. berkeley/los angeles: university of california press, , pp. – . . antoine goléa. rencontres avec olivier messiaen. paris: juilliard, , pp. – . . brigitte massin. une poétique du merveilleux. aix-en-provence: editions alinéa, , pp. – . . jean-françois labie. le visage du christ dans la musique des xixe et xxe siècles. paris: fayard, . © by the author; licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution license (http://creativecommons.org/licenses/by/ . /). applied microbiology, may , p. - copyright © american society for microbiology vol. , no. printed in u.s.a. notes black beauty out of mycobacterium fortuitum cruz ruth e. gordon and c. hor-nay pang institute of microbiology, rutgers university, new bruinswick, new jersey received for publication january a black-pigmented strain developed mycobacterium fortuitum. spontaneously from a typical strain of in , our strain no. was received from c. h. collins, public health service, county hall, london, as his strain no. of myco- bacterium species, a strain described as non- pigmented (fig. ia) and arylsulfatase-positive. shortly after its arrival, cultures of the strain were lyophilized. our tests and observations ( ), completed in , showed strain no. to be a typical strain of m. fortuitum (table ). after years of storage at c, during a routine examination of our lyophilized cultures, strain no. was revived on a slant of yeast- dextrose-agar ( ). one black-pigmented colony appeared among several isolated colonies above the confluent growth on the slant. the black colony was picked, and growth of the resulting deeply pigmented strain is shown in fig. lb. in addition to its black growth, this strain produced some dark, soluble pigment. cultures of the strain were strongly acid-fast, and its morphology was typical of the more rapidly growing myco- bacteria. except for less activity on trehalose, the black-pigmented strain had the same physio- logical characteristics as its parent strain (table ). the pigmentation of cultures of m. fortuitum on various media, varying from straw-colored to black, has been described ( , , - , ). oc- casionally, old cultures of m. jortuitum on glycerol-agar (containing soil extract) formed a deep black soluble pigment ( ); the growth, however, remained whitish, and subcultures of these pigment-forming old cultures did not blacken the medium. the black-pigmented daughter strain from our strain no. is the only m. jortuitum to produce black growth that we have observed. as shown in fig. c, sectors of the original whitish growth appeared in some cultures of the black strain, and the dark pigment is not a stable property of the strain. this investigation was supported by public health service grant ai- from the national institute of allergy and infec- tious diseases. literature cited . cerb n, j., and l. f. bojalil. . physiological relationships of rapidly growing mycobacteria. j. gen. microbiol. : - . . cerb n, j., and a. trujillo. . a comparison of methods for the classification of mycobacteria, utilization of carbon sources and deamidase tests. amer. rev. resp. dis. : - . . gordon, r. e. . some strains in search of a genus- corynebacterium, mycobacterium, nocardia or what? j. gen. microbiol. : - . . gordon, r. e., and j. m. mihm. . a comparison of four species of mycobacteria. j. gen. microbiol. : - . . kushner, d. s., s. mcmillen, and m. senderi. . atypical acid-fast bacilli. ii. mycobacterium fortuitum: bacteriologic characteristics and pathenogenicity for laboratory animals. amer. rev. tuberc. : - . . moore, m., and j. b. frerichs. . an unusual acid-fast infection of the knee with subcutaneous, abscess-like lesions of the gluteal region. j. invest. dermatol. : - . . ross, a. j. . mycobacterium salmoniphilium sp. nov. from salmonoid fishes. amer. rev. resp. dis. : - . . tsukamura, m. . salicylate degradation test for differ- entiation of mycobacterium fortuitum from other myco- bacteria. j. gen. microbiol. : - . . waksman, s. a. . the actinomycetes, p. . chronica botanica co., waltham, mass. . wells, a. q., e. agius, and n. smith. . mycobacterium fortuitum. amer. rev. tuberc. : - . fig. . growth of mycobacterium fortuitum on yeast-dextrose-agar. (a) original straint no. ; (b, c) strain n o. black. incubation, weeks. x . o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://a e m .a sm .o rg / d o w n lo a d e d fro m http://aem.asm.org/ .>. . @ _ r < . o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://a e m .a sm .o rg / d o w n lo a d e d fro m http://aem.asm.org/ appl. microbiol. table . some physiological reactionts of myco- bacterium fortuitum ir,rn-y decomposition of casein ................ tyrosine .............. urea ................. deamination of phenyl- alanine ............... hydrolysis of starch ................ hippurate ......... growth at c ............... c ............... c................. survival at c, hr. acid from arabinose ......... dulcitol ............ erythritol ........... galactose ............ glucose ............ inositol .............. lactose ............... mannitol .......... mannose .............. a-m-d-glucoside .... raffinose.............. rhamnose. sorbitol. trehalose ............. xylose .. . ...... utilization of benzoate ........... citrate ............. lactate ............. malate .............. mucate ........ oxalate...... ........ succinate ............. growth on dyes methyl violet ....... pyronin ............... color change of mac- conkey agar. resistance to penicillin, units. bacitracin, units.... production of arylsul- fatase, days......... growth in ( . %) sali- cylate broth........... strain strainn strains of i uuu black m. fortuiititm( ) ( ) + + + + +r + + a ± + + ± + + ± + + ± + + + ± ± a- + - ( )h - ( ) + ( ) - (i) + ( ) + ( ) - ( ) + ( ) + ( ) - ( ) -( ) - ( ) - ( ) - ( ) + ( ) - ( ) - ( ) f ( ) ± ( ) - ( ) - ( ) - ( ) - ( ) + ( ) - ( ) - ( ) ± ( ) ± ( ) + ( ) - ( ) - ( ) + ( ) + ( ) ± ( ) + ( ) + ( ) ± ( ) + ( ) ± ( )d symbols: +, to %' of strains positive; ±, to '' of strains positive; f, to % of strains positive; -, to %, - of strains positive. numbers in parentheses represent per cent positive strains. c trace. d only strains were tested. notes o n a p ril , a t c a r n e g ie m e l l o n u n iv l ib r h ttp ://a e m .a sm .o rg / d o w n lo a d e d fro m http://aem.asm.org/ /home/www/ftp/data/hep-ph/dir_ / .dvi anl-hep-pr- - mri-p- efi- - beautiful mirrors and precision electroweak data d. choudhurya,b, t.m.p. taita and c.e.m. wagnera,c ahep division, argonne national laboratory, cass ave., argonne, il , usa bharish-chandra research institute, chhatnag road, jhusi, allahabad , india cenrico fermi institute, univ. of chicago, ellis ave., chicago, il , usa september , abstract the standard model (sm) with a light higgs boson provides a very good de- scription of the precision electroweak observable data coming from the lep, sld and tevatron experiments. most of the observables, with the notable exception of the forward-backward asymmetry of the bottom quark, point towards a higgs mass far below its current experimental bound. the disagreement, within the sm, between the values for the weak mixing angle as obtained from the measurement of the leptonic and hadronic asymmetries at lepton colliders, may be taken to indicate new physics contributions to the precision electroweak observables. in this article we investigate the possibility that the inclusion of additional bottom-like quarks could help resolve this discrepancy. two inequivalent assignments for these new quarks are analysed. the resultant fits to the electroweak data show a significant improvement when compared to that obtained in the sm. while in one of the ex- amples analyzed, the exotic quarks are predicted to be light, with masses below gev, and the higgs tends to be heavy, in the second one the higgs is predicted to be light, with a mass below gev, while the quarks tend to be heavy, with masses of about gev. the collider signatures associated with the new exotic quarks, as well as the question of unification of couplings within these models and a possible cosmological implication of the new physical degrees of freedom at the weak scale are also discussed. introduction the electroweak precision tests, driven primarily by the experiments at lep, the teva- tron and the slc, have, in recent years, held much of the attention of the field. taken in conjunction with the measurement of the top mass and certain other low energy measure- ments, these experiments have vindicated the standard model (sm) to an unprecedented degree of accuracy [ ]. while startling deviations from the sm expectations have occa- sionally appeared, only to disappear later as the precision increased, the results of the precision tests have been remarkably steady over the last five years. yet, certain discrep- ancies persist. it is thus contingent upon us to examine their significance and especially to ascertain whether they could be pointers to new physics at the weak scale. in this article, we shall concentrate upon the most obvious of such a possible devia- tion [ ], namely the forward-backward asymmetry (abf b) of the b-quark, the measurement of which shows a . σ deviation from the value predicted by the best fit to the precision electroweak observables within the sm [ , ]. one might, of course, argue that this discrep- ancy is but a result of experimental inaccuracies and/or just a large statistical fluctuation. this viewpoint is supported, to some extent, by the observation that the corresponding sld measurement of the b-asymmetry factor ab using the lr polarized b asymmetry is in much better agreement with the sm [ ]. it has also been argued that any correction to the b̄bz vertex, large enough to ‘explain’ abf b would have shown up in the very accurate measurement of rb, the branching fraction of the z into b’s. however, we shall demon- strate that this need not be so. but more importantly, given the remarkable consistency amongst the four lep experiments as regards abf b, it is perhaps worthwhile to take this deviation from the sm seriously and to speculate on possible explanations thereof. let us begin by reviewing the relevant data at the z-peak. we parametrize the effective zbb̄ interaction by lzbb̄ = −e sw cw zµb̄γ µ [ ḡblpl + ḡ b rpr ] b ( ) where sw ≡ sin θw , cw ≡ cos θw and pl,r are the chiral projection operators. an analogous definition holds for the other fermions. within the sm, the tree-level values of the chiral couplings g f l,r are determined by gauge invariance. the weak radiative corrections to the same are well-documented and are insignificant for all but the b-quark. clearly then, rb ≡ Γ(z → bb̄) Γ(z → hadrons) ' (ḡbl) + (ḡbr) ∑ q [(ḡ q l) + (ḡ q r) ] ( ) where the sum is to be done over all the light quarks. the forward-backward asymmetry at lep, on the other hand, is given by abf b|√s'mz = a` ab ( ) with ab ' (ḡbl) − (ḡbr) (ḡbl) + (ḡbr) a` ' (g`l) − (g`r) (g`l) + (g`r) . ( ) small corrections also accrue to the above observable from a non-zero b-quark and c- quark masses as well as qcd, electroweak and electromagnetic vertex corrections [ – ]. whereas the observed values are rb(obs) = . ± . , abf b(obs) = . ± . , ( ) the sm expectations for a top quark mass of . gev and a higgs mass close to its present experimental bound, are rb(sm) ' . and abf b(sm) ' . . thus, while the observed value for rb is consistent with the sm, that for a b f b shows, as emphasized before, a relatively large deviation from the predicted value. this relatively large dis- crepancy may be reduced by choosing larger higgs masses, although only at the cost of worsening the agreement between theory and experiment for other observables, most notably the lepton asymmetries. it has been noted, for example in ref. [ ], that the overall consistency of the sm with the data improves if we dismiss altogether the measurement of the forward-backward asymmetry. such an act of exclusion leads to a preference for new physics scenarios that produce a negative shift in the oblique electroweak parameter s [ ], an example being provided by supersymmetric theories with light sleptons [ ]. we, instead, choose to consider all experimental data on equal footing. in this article, we investigate a possible way of resolving the disagreement between the hadronic and leptonic asymmetries through the introduction of new quark degrees of freedom at the weak scale thereby inducing non-trivial mixings with the third generation of quarks. in section , we examine the experimental status in order to determine the necessary modifications in the couplings of the right- and left-handed bottom quarks. as the required modification in the right-handed sector turns out to be too large to be obtainable via radiative corrections, we investigate, in section , the possibility that tree-level mixing of the bottom quark with exotic quarks might be responsible for the observed deviations. all possible assignments for such quarks are examined for their effects on the precision electroweak observables and the two simplest choices identified. the fits to the data for the two cases are presented in sections and respectively. other phenomenological consequences, including the question of unification, will be investigated in sections and . we reserve section for our conclusions. bottom quark couplings confront data let us assume a purely phenomenological stance and attempt to determine ḡbl,r from the data. even in the limit of infinite precision, the ellipse and the hyperbola representing the solution spaces for eqs.( , ) intersect at four points with the coordinates given by (ḡbl, ḡ b r) ≈ (± . gbl(sm), ± . gbr(sm)) , ( ) where we indicate on the right the approximate values of the left- and right- handed couplings necessary to fit the bottom-quark production data at the z-peak . clearly, no experiment performed at the z-peak can reduce the degeneracy any further. - - . . a b f b √s (gev) (+, +) (+, −) (−, +) (−, −) pep petra venus topaz lep-i l aleph opal delphi figure : the forward-backward asymmetry for the b-quark as a function of √ s for the four solutions of eq.( ). the signs in the parentheses refer to those for (ḡbl, ḡ b r) in the same order as in eq.( ) with (+, +) being sm-like. the experimental data correspond to the measurements reported in refs. [ – ]. off the z-peak though, the photon-mediated diagram becomes important thereby affecting the forward-backward asymmetry of the bottom-quark. such data, thus, could discriminate amongst the four solutions described above. the asymmetry is easy to calculate and in fig. , we plot the same as a function of the center of mass energy of the e+e− system for each of the solutions in eq.( ). it is quite apparent that the two solutions with ḡbl ≈ −gbl(sm) can be summarily discarded. interestingly enough, the data does not readily discriminate between the two remaining solutions. this, though, is not unexpected as |gbr| � |gbl| within the sm. a similar analysis can be performed for rb as well, but the off-peak measurements of this variable are not accurate enough to permit a similar level of discrimination. a similar analysis, although restricted to modifying the magnitude but not the sign of the couplings, was performed in ref. [ ] had we instead held the magnitudes of the couplings to their sm values, the resulting curves would have been barely distinguishable from those in fig. . it is quite interesting to note that the agreement with the next best measurement of abf b, viz. that at petra ( gev) is much better for the (+, −) choice than for the sm (or the ‘sm-like’ solution). this observation can be quantified by performing a χ test including all the data shown in fig. . it can easily be ascertained that the χ is indeed significantly improved if the sign of ḡbr were to be reversed. whether this information actually calls for a such a reversal is, of course, open to interpretation. - . - . . . . . . - . - . . . . δ g r δ gl - . - . - . - . - . - . - . - . - . - . . . . δ g r δ gl figure : the regions in the zb̄b coupling parameter space that are favoured by the observed values of abf b (flatter curves) and rb (steeper curves). for each set, the innermost curve leads to the experimental central value while the sidebands correspond to the σ and σ error bars. the standard model point is at the origin. any resolution of the abf b anomaly through a modification of the zbb̄ couplings must then lie within one of two disjoint regions of the parameter space, regions that we exhibit in fig. . what immediately catches the eye is that the required shifts in the coupling satisfy |δgr| � |δgl|, a condition that would prove crucial at a later stage of our analysis. at this point, it is perhaps worthwhile to note that the two other (ruled out) branches of the solution space would have required a very large |δgl|, a shift that is very hard to obtain in any reasonable model. beautiful mirrors we now turn to the question of whether the required δgr,l could arise naturally as con- sequences of ordinary-exotic quark mixing. to keep the discussion simple, yet without losing track of any subtle effects, let us, for now, confine ourselves to just one additional set of quarks. any extension of the model would not change the qualitative aspects of our analysis. we shall also, for the time being, neglect any mixing with quarks of the first two generations . at this stage, we do not make any further assumptions about the quantum numbers of these new quarks. working in the basis (b′ , b ′ ), where the primes indicate weak-interaction eigenstates and b′ refers to the exotic b-quark, the mass matrix can be parametrized as lmb = − ∑ ij b̄′ilmij b ′ jr + h.c., m ≡ ( m m m m ) ( ) where the subscripts l, r refer to the quark chirality, and the (in general, complex) elements mij represent either a bare mass term or one derived from the higgs mechanism. it is a straightforward task, then, to obtain the mixing matrices for the left- and right- handed quarks (as well as the mass eigenvalues) by diagonalizing the matrices mm† and m†m respectively. ordinary-exotic mixings would generically introduce additional parameters in the charged current structure and, more importantly for us, in the neutral current sector as well. any such deviation from the sm structure depends crucially on the isospins of the exotics, and for the new left- and right-handed b′ fields, we denote these values by t l(r). let us concentrate on the neutral currents in the b-sector, more specifically on the part independent of the charge generator expressed in terms of the physical states (mass eigenstates), these can be parametrized as j µ(b) = e sw cw ∑ ij b̄iγµ(lij pl + rij pr)bj , l ≡ ( t ls l − c l −(t l + )slcl −(t l + )slcl t lc l − s l ) r ≡ ( t rs r −t rsrcr −t rsrcr t rc r ) ( ) where sl,r ≡ sin θl,r etc parametrize the left- and right-handed mixing matrices in the b-sector and sw (cw ) denote the sine (cosine) of the weak mixing angle. as expected, we would have flavour-changing neutral currents if either t l = − / or t r = . the presence of any such coupling would play a crucial role in the discovery of such an exotic and we shall return to this later. since the shifts in gbl,r are given by δgbl = ( t l + ) s l , δg b r = t rs r , ( ) it follows that the right handed component of the exotic cannot be a su( )l singlet. in principle, we could allow each of b′l and b ′ r to lie in any (and inequivalent) repre- sentation of su( )c ⊗su( )l ⊗u( )y . however, the requirement of anomaly cancellation a negligibly small mixing with the first and second generations may be enforced, for instance, by additional gauge interactions, such as top-color [ – ], top-flavor [ – ] or bottom-color [ ]. any mixing which respects u ( )em must be between objects of the same charge q and thus there are no mixing effects proportional to q. indicates that a vector-like coupling for the exotics is the most economic choice. in addi- tion, the introduction of vector-like fermions, unlike the one of their chiral counterparts, do not lead to large contributions to the oblique electroweak parameter s [ ], thereby preserving the agreement with precision data. we shall, therefore, limit ourselves to only such quarks. we refer to these exotic quarks as (beautiful) mirrors in the sense that they occur in vector-like pairs and they have the same electric and color charges as the ordinary bottom- (or beauty-) quark. as we have already mentioned, nonzero quark mixing requires that there be mass terms connecting the ordinary b-quark to its exotic counterpart. demanding that the only scalars in the theory be the su( ) higgs boson doublets restricts the choice of the exotics to a su( ) singlet and two varieties each of su( ) doublets and triplets. the phenomenological requirement of t r = eliminates the singlet and one of the triplets as the possible source for the large modification of the right-handed bottom quark coupling. the choice then devolves to one of Ψl,r = ( , , / ), ( , , − / ) and ( , , / ). the phenomenological consequences of the first and last possibilities are similar and hence we shall concentrate on studying the first two cases. scenario with standard mirror quark doublets our first scenario relies on the introduction of the fermion doublets Ψtl,r = (χ, ω) ≡ ( , , / ), ( ) which are a mirror copy of the standard quark doublets of the standard model. the most general yukawa and mass term in the lagrangian is then l ⊃ − ( y q ′ l + y Ψl ) b′rφ − ( x q ′ l + x Ψ ′ l ) t′rφ̃ − m Ψ ′ lΨ ′ r + h.c., ( ) where the primes, once again, denote weak eigenstates. note that, on account of Ψ ′ l and q′l having the same quantum numbers, a mass term of the form q ′ lΨr can be trivially rotated away. in the basis (b′, ω′), we then have a mass matrix of the form mb = ( y y m ) , yi ≡ yi〈φ〉 ( ) and an analogous one for the top. for the sake of simplicity, we shall assume that the mass matrices are real. in the phenomenologically interesting regime of y � y < m , we have, for the eigenvalues of the mass eigenstates b, ω and the mixing angles mb ≈ y ( + y m )− / , mω ≈ (m + y ) / , tan θbr ≈ −y m tan θbl ≈ −y y m + y , ( ) with analogous expressions for the top-sector. a few points are to be noted: • since both ω′l and χ′l have the same quantum numbers as their ordinary counter- parts, neutral currents in these sectors remain unmodified. • as δgbr < (while gbr(sm) > ), a small δgbr would only worsen the fit. rather, we must demand a large negative correction that would take us to the second allowed region in the parameter space (see fig. ). for example, a σ agreement for each of abf b and rb is obtained for δgbr = −s r ≈ − . =⇒ y ≈ . m . ( ) • the top-sector mass matrix is as in eq.( ) but with yi → xi. since the y’s and x’s are independent, one could, in principle, set x = (this, for example, could be ensured by imposing a discrete symmetry). in such a case, the top sector sees no additional mixing and x is the usual top yukawa coupling. • since no exotic quark has yet been seen at the tevatron collider, m >∼ gev. • in general, due to the large mixing in the bottom sector and the fact that the right- handed mirror quarks carry non-trivial weak charges, a potentially large correction to the precision electroweak parameters will accrue. • a right-handed w -t-b interaction is induced with strength proportional to sbrstr. measurement of b → sγ requires sbrstr < . [ ], leading us to consider the case of negligible χ-t mixing. in order to address the question of how well does this scenario fit the data, we have computed the corrections to the s, t and u parameters, with respect to a reference higgs mass value of gev. while the corrections to u are small, the corrections to t and s are large and increase with the overall scale of quark masses. for instance, for m = , , gev the corrections to the t parameter are ∆t ' . , . , . respectively, while the correction to the parameter s is somewhat insensitive to the masses and measures ∆s ' . . the large corrections to the t parameter, together with the relatively large corrections to the right-handed bottom couplings, tend to increase the hadronic width and the total width of the z to unacceptable levels. this problem can be ameliorated by including the mixing of the bottom quark with a quark ξr,l carrying the quantum numbers of the right-handed bottom quark and its mirror partner. in the basis (b′, ω′, ξ′), the simplest modification to the mass matrix that fulfills this requirement is given by: mb =   y y y m m   , yi ≡ yi〈φ〉 ( ) note that, as happens with (mb) , the element (mb) could also be trivially rotated away. the inclusion of small, but non-zero, values of the elements (mb) and (mb) only serves to complicate matters without modifying the main phenomenological consequences of this model. ignoring small terms proportional to the bottom quark mass, the left-handed mixing angle is now given by sl ' y √ y + m ( ) the main effect of the mixing with these weak singlet quarks is to reduce the left-handed coupling of the bottom quark and thus the partial width of the z into b’s and hence into hadrons as such. the scenario described above can thus clearly improve the agreement with abf b. for small values of sl, as demanded by experimental results, the oblique corrections to the precision electroweak observables are still dominated by the large mixing of the bottom quark with the weak mirror quark doublet. the presence of the new quarks will, of course, induce additional radiative corrections to the b-quark couplings. it is easy to see though that, given the above-mentioned mass and mixing angle pattern, these corrections are tiny compared to those induced at the tree level, and hence could be safely neglected. once again, non-observation of an exotic quark at the tevatron implies m >∼ gev. the parameters s, t and u are in one to one correspondence with the variations of the parameters � , � and � , introduced in ref. [ ] with respect to a given value of the top quark mass and the higgs mass. the relation between these parameters is given by: ∆� = αt, ∆� = αs s w , ∆� = − αu s w , ( ) and, within the sm, for a top quark mass mt = . gev and a higgs mass mh = gev, � = . − , � = − . − and � = . − [ ]. the dependence of the �i parameters on the higgs and top quark masses may be found, for instance, in ref. [ ]. the dependence of the most important observables on the parameters �i are given by Γz ' . ( + . � − . � + ...) gev sin θeffl ' . ( − . � + . � ) m w m z ' . ( + . � − � − . � ) , ( ) where the dots reflect the contributions associated with the variations of the b-coupling due to radiative corrections and the mixing with the b quarks. there is, in addition, a dependence on the precise value of α(mz ) and αs(mz ). in our computations we have used the central values for the hadronic contribution to α(mz ) namely ∆α ( ) had = . [ ], while the strong gauge coupling was allowed to float around the central value of . [ ]. variations in the parameter t larger than . tend to induce a large positive correction to the total z width, and are therefore disfavored by the data. consequently, this model leads to a better fit to the data whenever the new quarks are relatively light and the higgs is heavy. in general, a heavy higgs leads to a negative contribution to t and a positive contribution to s, leading to a better agreement with the total width of the z. however, the same effects worsen the agreement of the data with the leptonic asymmetries, which mainly depend on sin θeffl . therefore, the model leads to a correlation of the quark and higgs masses: the heavier the new quarks, the heavier the higgs needs to be. the value of αs also plays an important role in this process, since it may lower the total hadronic width without modifying the leptonic asymmetries. we have made a fit to the data within this model. including the values of y , m , αs, mt, mh and sl as variables in the fit (the fit is quite insensitive to the scale m , provided it remains below a a few tev), we obtain that the best fit to the data is obtained for the mirror quark mass parameter m close to the present experimental bound on this quantity, while the preferred values of the higgs mass are about gev. raising the quark bound to gev leads to an optimal value of the higgs mass of about gev. the best fit gives αs ' . and mt ' gev. for the exotic sector, the corresponding values are y ' . m , m ' gev ( ) while s l ' . . ( ) the best fit to the ratio y /m and to s l are virtually independent of m for gev <∼ m <∼ gev. in fig. we show the - and -σ regions in the mh –mχ parameter space determined by the best fit to the data. as emphasized above, the model leads to a preference for light quarks, with masses below or about gev, within the reach of the tevatron collider (see section ), while the preferred values of the higgs mass are much larger than in the standard model, a feature that appears in many models [ ]. for the parameters providing the best fit, all measured precision electroweak observ- ables, including the lepton and hadron asymmetries and the z widths are within σ of the predictions of this model, and, in particular, the bottom asymmetries are within σ of the predicted values. similar results are obtained for slightly larger values of m , although the model is clearly disfavored for quark masses m > gev. while the agreement between theory and experiment for the bottom-quark asymmetries is remarkably better than in the standard model, the lepton asymmetries remain essentially the same as in the sm. this is due to the tension between these observables and the total z-width within this model and is reflected in the fact that the fit produces sin θeffl ' . . ( ) as a result, the left-right lepton asymmetry is about . standard deviations away from the value measured at sld thus marginally worsening the discrepancy obtained within the standard model. the w mass is, instead, in excellent agreement with the predictions of this model. σ σ mh (gev) m χ ( g ev ) figure : region in the mh –mχ parameter space (in the model with standard mirror quark doublets) that is consistent with the best fit point (marked) at the % c.l. and . % c.l. respectively. top-less mirror quark doublets let us now analyze the case in which the mirror quarks belong to a doublet in which there is no quark with the same charge as the top quark, viz., Ψtl,r = (ω, χ) ≡ ( , , − / ). ( ) this model has some advantages with respect to the model analyzed above. first of all, since the weak partner of the ω has charge − / , there is no mixing involving the top quark. second, the model allows for a modification of the right-handed bottom couplings with moderate mixing angles. in the basis (b′, ω′), the mass matrix reads mb = ( y yr m ) , yi ≡ yi〈φ〉 , ( ) where the zero entry is now enforced by gauge invariance. the right and left-handed mixing angles have similar expressions to the ones found in the above model. however, the mixing of the right-handed bottom leads to a positive shift of gbr, δgbr ' s r ( ) and therefore small values of sr can lead to a relevant shift of a b f b in the direction required by experiment. as in the previously analyzed model, the values of rb and of the hadronic width can be improved by allowing an additional mixing with a quark ξ with the same quantum numbers as the right-handed bottom quark and its mirror partner. in the basis (b′, ω′, ξ′), we assume a mass matrix quite similar to the one in the last section: mb =   y yl yr m m   , yi ≡ yi〈φ〉 ( ) as with the previous model, the matrix element (mb) can be trivially rotated away, while the inclusion of small (compared to mi) but non-vanishing matrix elements (mb) and (mb) do not change the main results of our analysis. ignoring small effects induced by the bottom mass, the left-handed and right-handed mixing angles are given by sl ' yl√ y l + m , sr ' yr√ y r + m . ( ) the main difference between this model and the one analyzed before lies in the smallness of all the mixing angles. since all yukawa couplings are small compared to the explicitly gauge invariant masses, the corrections to the oblique parameters s, t and u are small. the corrections to t become relevant only for quark masses above gev, while the corrections to s and u remain small even for masses in the multi-tev range. since the expected bottom-quark asymmetry has now migrated much closer to the measured value, the data now prefers non-negligible values of the t parameter so as to permit a better agreement with the lepton asymmetries and the w mass. this can only be achieved by pushing the quark masses up, while keeping the higgs mass close to its experimental lower bound. we have analyzed all the precision observables in the context of this model, as de- scribed by the parameters mh , mt, αs, m , yr, m and yl. the best fit to the data is obtained for a higgs mass close to the present experimental bound and mirror quark doublets with mass of about m ' gev and yr ' gev, ( ) implying that s r ' . . the best fit value of m is close to its experimental bound, m ' gev, while yl ' gev, leading to s l ' . . similar to the previously analyzed scenario, changing m while keeping the ratio of yl/m does not alter the fit in any significant way. the best fit values of αs and mt are αs ' . and mt ' gev. in fig. we show the - and -σ regions in the mh –m parameter space obtained by the best fit to the data. as emphasized above, the higgs tends to be light, in the region most accessible to the tevatron collider and a √ s = gev linear collider. the quarks, instead, tend to be heavy with masses of about tev. for m above a few tev though, σ σ mh (gev) m (g ev ) figure : region in the mh –mχ parameter space (in the model with top-less mirror quark doublets) that is consistent with the best fit point (marked) at the % c.l. and . % c.l. respectively. the yukawa coupling yr needed to improve the fit to the data becomes large, spoiling the perturbative consistency of the theory at low energy scales. this model provides a surprisingly good agreement with the experimental data. for the parameters providing the best fit to the data, the left-right lepton asymmetry mea- sured at sld is . standard deviations from the theoretically predicted value, while almost all other measured observables are within σ of the predictions of this model. the only exceptions are the charm forward-backward asymmetry and the total hadronic cross section measured at lep, which stay within σ of the measured values. as already pointed out, the fitted value sin θeffl ' . ( ) exhibits a much better agreement with the leptonic asymmetries than in the model with standard mirror quarks. implications at present and future colliders although the two models presented above share many features, there are subtle differences as far as the collider signatures are concerned. we shall examine, in some detail, the scenario containing a top-like quark and then point out the differences with the second model. any new quark [ ], with a mass below or about gev, as preferred in the model with standard quark doublets, should be observable at the next run of the tevatron collider. the main decay of the χ-quark will be similar to that of the top quark, namely, χ → b + w +. ( ) although the ω-quark tends to be somewhat heavier than the χ-quark, yet it should be possible to pair-produce it at the tevatron collider, especially if m turns out to be in the (lower) range preferred by the electroweak fit. on account of the phase space restrictions, it would decay mainly through the flavor violating channel, viz., ω → b + z ( ) a mode that has already been looked for at the run i of the tevatron with a resultant lower limit of about gev on mω [ ]. this very same flavor-changing neutral current interaction, would, at a next generation linear collider, lead to a rather significant cross section for the process e+ + e− → b̄ + ω, ( ) as well as the conjugate state, thereby leading to rather striking signatures. there is no prediction for the singlet quark mass within this models. if they were light, in the range accessible to the tevatron collider, they will mainly decay via its flavor violating couplings ξ → b + z , ( ) or, in the event of a non-zero (mb) , also into an ω-quark: ξ → ω + z. ( ) due to its larger center of mass energy, the lhc, should be able to test this model for even larger values of the ω- and χ- quark masses. finally, we turn to the higgs. note that the yukawa coupling matrix is proportional to that in eq.( ) with the gauge invariant masses m , switched off. this immediately implies that the yukawa interactions are not diagonal in the mass-basis. this is quite crucial especially since the coupling y is quite large (actually, of the same order as the top yukawa in the sm). while the full expressions for the resultant yukawas are cumbersome, they simplify considerably in the limit of a vanishing y to lbwφ ∼ y (cr ω̄lbr − sr ω̄lωr) φ + h.c. + o(y ) ( ) thus, for mφ > mω + mb, a condition satisfied over almost the entirety of the preferred parameter space (see fig. ), the higgs is afforded an additional decay mode. and, if the higgs is more than twice as heavy as the ω (again, true for a very large part of the σ preferred area), a further decay channel would open up, although with a branching fraction smaller than that for the flavour-changing mode. while this results in a severe depletion of the ‘gold-plated’ modes (φ → zz → l), presumably these non-canonical channels would lend themselves easily to discovery, especially with the b- (and lepton-) richness of the final state. in the top-less mirror quark model, instead, the quark doublets are predicted to be heavier. only the lhc (or a second generation linear collider) would have enough center of mass energy to produce the ω and χ in this case. the quark χ (with a − / charge) will decay into χ → b + w − , ( ) leading to a top-like signature with a wrong sign w . similarly, due to phase space restrictions, ω → z + b ( ) since the flavour changing coupling is smaller in this case as compared to the previous model, non-diagonal production at a linear collider would be somewhat suppressed. also, with the higgs preferring to be light, and with its couplings to the new states not being as large as in the other model, higgs phenomenology remains largely unchanged from the sm. as happens in the model with standard mirror quarks, there is no prediction for the singlet mirror quark masses. if they are available at the colliders, they will decay via its flavor violating coupling: ξ → b + z . ( ) and since ξ prefers to be lighter than ω, a non-zero (mb) would, once again open an additional decay channel, viz., ω → ξ + z . ( ) unification the question of unification within these models is an interesting one. it might be ar- gued that this is not a pertinent one, since we have not detailed any mechanism to keep the higgs boson and vector quarks naturally light. the hierarchy of masses may arise through some hitherto undiscovered mechanism, which must be related to the one leading to the breakdown of the electroweak symmetry, and will probably require extra gauge symmetries [ – , – ]. the presence of any such extra symmetry would certainly alter unification in a highly model-dependent way. it is still possible though to discuss the issue of unification without delving into the details of the implementation of such a symmetry, as long as one assumes that the low-energy spectrum is determined, besides additional complete su( ) multiplets [ ]. this is the approach that we adopt in this section. we shall proceed with a one-loop analysis, taking into account that the possible two- loop effects are of the order of the small threshold effects at the grand unification scale, and hence become strictly relevant only for the construction of a complete grand unified model, an objective which is beyond the scope of this article. in the model with standard mirror quarks the beta-function coefficients of the three gauge couplings are given by b = − + ng + b = − + ng + nh + b = ng + nh + ( ) where the last term in each line relates to the extra contribution induced by the presence of the mirror doublet and singlet bottom quarks, ng is the number of generations and nh is the number of higgs doublets. to be consistent with the electroweak fits described earlier, we assume that only one higgs doublet plays a relevant role in electroweak symmetry breaking. this model predicts a shift of the hypercharge beta-function that is somewhat smaller than the equal shifts of the beta-functions of the weak and strong gauge couplings. as is well-known, within the sm, the strong and weak gauge couplings meet at approximately gev (for nh = ). the hypercharge coupling, however, crosses the other two at a much lower scale. this big ‘discrepancy’ can be reduced by postulating a large number of higgs doublets, but only at the cost of bringing down the unification scale to ∼ gev, a value palpably inconsistent with proton stability. the introduction of the new quarks and the consequent shift in the beta-functions works to reduce this very same difference in the scales at which the couplings meet. the improvement is quite significant. for nh = , and , and ‘unification’ scales of approximately × gev, × gev and gev, the couplings differ from the average “unification”value by less than , . and percent respectively . these corrections are small, and considering the large scales involved, as emphasized above, could easily be accommodated (even for nh = ) by threshold effects due to the presence of heavy particles (with gut scale masses) or planck scale suppressed operators. observe that, since the model lacks supersymmetry, dangerous dimension five opera- tors are absent from a potential grand unified scenario. moreover, the unification scale is sufficiently large to avoid the constraints coming from proton decay induced via di- mension operators. however, for the higgs masses and yukawa couplings associated with the best fit to the precision electroweak data, the model tends to induce a landau pole in the higgs quartic couplings below the gut scale, particularly for relatively heavy quarks, m ' gev. the most obvious means of avoiding this problem is to give up the property of perturbative unification. an alternate way would be to effect a suitable modification such as the one that we discuss shortly. in the model with the non-standard mirror doublet quarks, instead, the unification relations are not improved with respect to the standard model case, since the shift in the two-loop effects will produce small modifications to these numbers. beta function of the hypercharge gauge coupling is larger than in the ones associated with the strong and weak coupling beta-functions. however, this model presents an interesting property: the mirror doublet and singlet quarks introduced in this model are contained in the adjoint ( ), and in the + ̄ representations of su( ). indeed, the weak doublet and singlet quarks in this model have precisely the same quantum numbers as the -plet partners of the standard model gauginos and of the color-triplet higgsinos of the minimal supersymmetric standard model (mssm), respectively . on a more speculative note, if one were willing to accept the presence of a complete of fermions at the weak scale, together with the standard mirror doublet and singlet quarks , one could obtain excellent unification relations without the need of supersym- metry, together with an excellent fit to the precision electroweak observables. within this assumption, the top-less mirror quark doublets will be the ones leading to a relevant mixing with the bottom quark, while the standard mirror quark doublets should have only small mixing with the three generation of quarks. in this case, the higgs tends to be light. for a top-less doublet lighter than approximately tev, the yukawa couplings are relatively weak and the landau pole problem is avoided. this model may lead, instead, to a conflict with the higgs potential stability [ ]. whether this is a real physical problem can only be answered by studying the possibility of ours being a metastable vacuum. in the sm with a similarly light higgs, mh ' gev, the requirement of strict stability would suggest the presence of new physics far below the planck scale. the requirement of being in a metastable vacuum with lifetime longer than the age of the universe, in- stead, allows the standard model description to be valid up to scales close to the planck scale [ , ]. we postpone for a future study a more detailed analysis of these questions. observe that the above-mentioned possibility leads to the potential presence of fields with the quantum numbers of the mssm gauginos at low energies. in the absence of a symmetry like r-parity, the fields with the quantum number of the wino and of the bino will mix with the leptons and neutrinos, respectively, and hence their couplings to the leptons and the higgs bosons should be very small. if one assumes the presence of a second higgs doublet, with no relevant role in the electroweak symmetry breaking mechanism, a coupling of order one of this field with the bino-like field and, for instance, the third generation leptons may induce the proper annihilation rate to make the bino- like field a good dark matter candidate . alternatively, the bino may play the role of a sterile neutrino. without the addition of new fields, the gluino-like particle tends to be very long lived or even stable. we also reserve for a separate study the analysis of the cosmological and phenomenological consequences of such a scenario. in the minimal supersymmetric su ( ) model, the colored-triplet higgsinos are assumed to acquire gut scale masses , creating the so-called doublet triplet splitting problem. a similar hierarchy problem would exist in the model described in this section. all these fields are contained in the adjoint of e . discrete symmetries may need to be imposed in order to avoid dangerous lepton flavor violating processes. conclusions the standard model with a light higgs boson is in very good agreement with the preci- sion electroweak observables measured at the tevatron, sld and lep colliders. although there is no clear indication of the need for new physics in the electroweak precision mea- surement data, the prediction for the effective leptonic weak mixing angle extracted from the hadronic and leptonic observables are several standard deviations away from each other. in this article we have analyzed a possible way of fixing this discrepancy by in- troducing mirror quarks with quantum numbers similar to those of the left-handed and right-handed bottom quarks. while the two models analyzed in our article lead to an improvement of the general fit to the precision electroweak data, they present qualitatively different characteristic that make themselves easily distinguishable from the experimental point of view. in the model with standard mirror quark doublets, only negative shifts to the right-handed bottom coupling may be obtained by means of the mixing with the doublet and singlet quarks. the very smallness of this coupling within the sm, however, allows us not only to change its magnitude but reverse its sign as well. apart from improving the agreement to the precision electroweak data to a great extent, this also leads to interesting predictions for the bottom quark asymmetries away from the z peak. moreover, the best fit to the data within this model is obtained for quarks light enough to be accessible at the tevatron collider, and relatively heavy higgs bosons. finally, the unification relations are significantly improved with respect to the standard model case, and the potential unification scale is sufficiently large in order to avoid proton decay via dimension six operators. however, perturbative unification within this simple extension of the standard model is not possible, due to the presence of a landau pole in the higgs quartic couplings at scales below the potential gut scale. on the other hand, the model with non-standard mirror quark doublets leads to mild modifications of the left- and right-handed bottom quark couplings induced via small mixings of the mirror quarks with the standard ones. besides this, the model prefers relatively light higgs bosons, possibly in the range testable at the next run of the tevatron collider, while the mirror quarks tend to be heavy, only accessible at the lhc. an interesting property of this model is that the quantum numbers of the exotic quarks are precisely the ones of the heavy coloured gauginos and higgsinos within minimal supersymmetric su( ) scenarios. one can contemplate the possibility of taking both standard and exotic mirror quark doublets and the mirror down quark singlets, and including particles with the quantum numbers of the standard gauginos in the minimal supersymmetric standard model and, eventually, an additional higgs doublet. this extension of the standard model allows a remarkable improvement in the fit to the precision electroweak observable data, leads to the possibility of achieving consistency with the unification of gauge couplings and has all the ingredients necessary to lead to an explanation of the dark matter content of the universe. acknowledgements we would like to thank t. lecompte, p.q. hung and c.-w. chiang for useful discussions. cw would also like to thank m. carena, j. erler and m. peskin for useful comments. work supported in part by the us doe, div. of hep, contract w- - -eng- . dc thanks the deptt. of science and technology, india for financial assistance 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[ ] g. isidori, g. ridolfi and a. strumia, nucl. phys. b , ( ) [hep- ph/ ]. technion-ph- - weak radiative decays of beauty baryons paul singer and da-xin zhang department of physics, technion – israel institute of technology, haifa , israel abstract weak radiative decays of beauty baryons into strange baryons, induced by the elec- troweak penguin, are estimated by using a quark model approach. relations between formfactors in the semileptonic and in the weak radiative decays are derived within the heavy quark effective theory. the partial decay widths are found to be of the order of − mev for Λb → Λγ and Ξb → Ξγ and of the oder of − mev for Ωb → Ωγ. the Ωb radiative decay is thus expected at the sizable branching ratio of approximately − . pacs number(s): . .ds, . hg, . mr keywords: weak radiative decay, beauty baryon, heavy quark effective theory the investigation of the electroweak penguin transition b → sγ is of prime im- portance, both as a test of the standard model[ ] and as a possible window of new physics[ ]. the recent observation of the exclusive process b → k∗γ with a branching ratio of ( . ± . ± . )× − [ ] and of the inclusive process b → xsγ with a branch- ing ratio of ( . ± . ± . ) × − [ ] constitute solid evidence in the support of the interpretation of these decays in terms of the short-distance b → sγ transition. the theoretical treatment of this basic loop process using renormalization group equations to treat perturbative qcd corrections has been improved during recent years[ ], following the original assertion[ ] on the role of the qcd corrections in increas- ing the rate of this process to bring it into the realm of observability. the full leading order calculation of the process has been completed[ ] and the next-to-leading order calculation has also been partially performed[ ]. at present, the theoretical uncertainty of the standard model calculations is of the order of %[ ] and the experimental errors are even slightly higher[ , ]. along with the improvement in the theoretical calculations by the completion of the next-to-leading order calculation which should reduce the theoretical uncertainty, and the expected increased accuracies of future measurements, it is of obvious interest to investigate additional physical processes which are driven by the b → sγ transition. the weak radiative decays of beauty baryons are natural candidates for this task. indeed, preliminary estimates on such decays were undertaken recently by cheng et al[ ] and by cheng and tseng[ ] and an overview of this topic is given in ref. [ ]. in the present work, the weak radiative decays of the beauty baryons are inves- tigated by the use of the quark model employed by hussain et al[ ] and by körner and krämer[ ] to treat the semileptonic and the nonleptonic decays of heavy baryons. in their model, spin interactions between the spectator and active quarks are ignored and the q -dependence of all the formfactors are taken as pole-like. this approach is consistent with the heavy quark effective theory(hqet), as applied to baryons[ ]. the lowest lying baryons containing one heavy beauty quark can be classified into ̄, and ∗ under the su( ) flavor symmetry of the light quarks[ , ]. from among these states, only the spin / baryons Λ b , Ξ −, b of the antitriplet-baryons and Ωb of the sextet-baryons are expected to decay weakly. we consider here the weak radiative exclusive processes which can be induced by the short-distance b → sγ transition; these are Λ b → Λ γ, Ξ −, b → Ξ −, γ[ - ] and Ω−b → Ω −γ. additional radiative decays like Λb → Σcγ, Ξb → Ξcγ, which are caused by weak bremsstrahlung quark processes, were found to be very rare[ ] and will not be of our concern here. the basic mechanism for the decays considered here is assumed to be the quark level transition b → sγ, given by the following amplitude[ - ] a = gf √ e π c eff (µ)vtbv ∗ tsfµνs̄σµν[mb( + γ ) + ms( −γ )]b, ( ) where vtb and vts are cabibbo-kobayashi-maskawa matrix elements and fµν is the field strength tensor of the photon. the coefficient c eff (µ), which is the combination of several wilson coefficients running from µ ∼ mt to µ ∼ mb, has been calculated[ - ] to be c eff (mb = . gev) = . , ( ) when one uses mt = gev and Λqcd = mev . a different choice for the renor- malization point µ introduces the large uncertainty we mentioned. in order to calculate the baryonic transitions induced by b → sγ, our basic tool is the heavy quark effective theory which permits to relate[ , ] in the heavy quark limit the formfactors of the magnetic transition ( ) to those of the semileptonic decays. moreover, we treat the decays under consideration here as heavy-to-light (b → s) quark transitions. throughout the present paper, we neglect corrections in the mass parameter of the order /mb. needless to say, a more accurate approach should consider the mass correction as well, especially when the above mentioned uncertainty in ( ) will be reduced. we turn now to derive the formfactors required here. for a baryonic transition induced by a v −a current between spin / baryons, one generally has six formfactors. however, in the limit of the heavy quark mass mq →∞, using hqet one can express the relevant matrix element in terms of two independent formfactors only[ , ]. thus one has for Λb → Λ (and a similar expression for Ξb → Ξ), < Λ|s̄γµ( −γ )b|Λb >= ūΛ(p )[f (q ) + f (q ) p mΛb ]γµ( −γ )uΛb(p ). ( ) for the transition Ωb → Ω, where we have a heavy spin / baryon belonging to the -representation decaying into a spin / baryon belonging to the decuplet, the matrix element involves six independent formfactors[ ], which for the v −a current is < Ω|s̄γµ( −γ )b|Ωb > = ūΩ(p )α[g αβ(c + c p mΩb ) + p α mΩb p β mΩb (c + c p mΩb ) + p α mΩb γβ(c + c p mΩb )]γµ( −γ ) √ (γβ + p β mΩb )uΩb(p ). ( ) relating now by hqet[ ] the formfactors in ( )( ) to the matrix elements for the radiative decays, and contracting these with the electromagnetic tensor fµν, one obtains fµν < Λ|s̄σµν( + γ )b|Λb >= f µνūΛ(p )[f (q ) + f (q ) mΛ mΛb ]σµν( + γ )uΛb(p ) ( ) for the weak radiative decay Λb → Λγ (or Ξb → Ξγ), and likewise fµν < Ω|s̄σµν( + γ )b|Ωb > = f µνūΩ(p )α[g αβ(c + c mΩ mΩb ) + p α mΩb p β mΩb (c + c mΩ mΩb ) + p α mΩb γβ(c + c mΩ mΩb )]σµν( + γ ) √ (γβ + p β mΩb )uΩb(p ) ( ) for Ωb → Ωγ. a possible alternative approach which was used before[ , , ] is to establish firstly the relations between formfactors in the rest frame of the initial heavy hadron and then to boost them to a general lorentz frame. however, certain difficulties occur[ ] when carrying out this procedure for the Λb → Λγ, Ξb → Ξγ decays. in our approach to the weak radiative decays, we use eqs. ( )( ) with formfactors from the quark model as determined previously for the (v −a) current induced transi- tions. to calculate the decay rates for the various processes, we proceed as follows. for the → γ transitions, we use ( ) with the formfactors of ref. [ ] with monopole behavior and pole masses mv = . gev and ma = . gev, which gives f (q = ) = . ( . ),f (q = ) = − . (− . ), ( ) where the two given values are for the vector (axial) currents. using now ( ) and ( ) with vtb = , vts = . , this leads to Γ(Λb → Λγ) = . × − mev; Γ(Ξb → Ξγ) = . × − mev. ( ) if we use a lifetime of τ(Λb) = . ps[ ], which has an experimental uncertainty of about %, we arrive at a predicted branching ratio for Λb → Λγ br(Λb → Λγ) ' . × − . ( ) a similar figure would be obtained for Ξb → Ξγ decays, except that no measurement exists at present for the Ξb lifetime. our result in ( ) is smaller than the − order of magnitude obtained in [ ], though quite close to the recent result of ref. [ ]. a similar approach is used for the decay Ωb → Ωγ. in this case, using the quark model of ref.[ ], we obtain c (q ) = (mΩb + mΩ) − q mΩbmΩ h(q ), c (q ) = − h(q ), c (q ) = c (q ) = c (q ) = c (q ) = , h(q ) = √ − (mΩb −mΩ) /m pole − q /m pole , ( ) where again a monopole behavior, but with same pole mass of . gev has been used for all the formfactors. taking a mass for Ωb of . gev, we get Γ(Ωb → Ωγ) = . × − mev. ( ) it is interesting to remark that transitions involving Ωc → Ω are similarly larger than those for Λc → Λ and Ξc → Ξ by one or two orders of magnitude in the decay rates[ , , ]. these results are apparently a result of the strong ovelaps in the light flavour wavefunctions between the initial and final states in Ωb,c → Ω transitions. additional support for this picture is the fact that the lifetime of Ωc, recently measured to be . × − sec[ ], is considerably shorter than those of other weakly decaying charmed hadrons, which can also be understood qualitatively in this way[ ]. the branching ratio for Ωb → Ωγ is then br(Ωb → Ωγ) = . × − [ τ(Ωb) . × − sec ], ( ) where we have normalized the Ωb lifetime to . × − sec. the branching ratio in ( ) is larger by two orders of magnitude than that of Λb → Λγ in ( ). thus, from the present calculation, the Ωb → Ωγ decay mode is appearing as the most attractive baryonic exclusive channel for an alternative investigation of the b → sγ electroweak penguin. we conclude by a discussion on additional advantages of studying the weak radiative decay of the beauty baryons. among these processes, Ξ−b → Ξ −γ and Ωb → Ωγ are the cleanest on the theoretical side. neither of these processes involves the w-exchange or the w-annihilation diagrams, which give additional contributions in the weak radiative decays of other b-hadrons. also, the long distance contributions in this b-sector are small and under control[ ]. thus , the measurements of Ξ−b → Ξ −γ and of Ωb → Ωγ in future experiments, together with their improved theoretical estimations, will be helpful to obtain the needed insight on long distance contribution in weak radiative decays of the other beauty hadrons, as well as on the question of w-exchange contributions in those decays. this research is supported in part by grant - - from the ministry of science and the arts of israel. the research of p.s. has also been supported in part by the fund for promotion of research at the technion. references [ ] for a review, see: g. ricciardi , dsf-t- - , talk given at international euro- physics conference on high energy physics (hep ), brussels, belgium, jul - aug . 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[ ] e. golowich and s. pakvasa, phys. rev. d , ( ); h.-y. cheng, preprint ip-astp- - ; n.g. deshpande, x.-g. he and j. trampetic, phys. lett. b , ( ); g. eilam, a. ioannisian, r.r. mendel and p. singer , phys. rev. d (in print). breitenbach_beautyproofs beauty in proofs kant on aesthetics in mathematics angela breitenbach please cite the final version, forthcoming in european journal of philosophy (early view at doi: . /ejop. ) abstract it is a common thought that mathematics can be not only true but also beautiful, and many of the greatest mathematicians have attached central importance to the aesthetic merit of their theorems, proofs and theories. but how, exactly, should we conceive of the character of beauty in mathematics? in this paper i suggest that kant's philosophy provides the resources for a compelling answer to this question. focusing on § of the ‘critique of aesthetic judgment’, i argue against the common view that kant's aesthetics leaves no room for beauty in mathematics. more specifically, i show that on the kantian account beauty in mathematics is a non-conceptual response felt in light of our own creative activities involved in the process of mathematical reasoning. the kantian proposal i thus develop provides a promising alternative to platonist accounts of beauty widespread among mathematicians. while on the platonist conception the experience of mathematical beauty consists in an intellectual insight into the fundamental structures of the universe, according to the kantian proposal the experience of beauty in mathematics is grounded in our felt awareness of the imaginative processes that lead to mathematical knowledge. the kantian account i develop thus offers to elucidate the connection between aesthetic reflection, creative imagination and mathematical cognition. . introduction it is a common thought that mathematics can be not only true but also beautiful, and some of the greatest mathematicians have attached central importance to the aesthetic merit of their work. many have derived aesthetic pleasure from mathematical research, pointing out the incomparable beauty and elegance of particular theorems, proofs and theories. as the french mathematician and theoretical physicist henri poincaré put it, mathematical beauty is a 'real aesthetic feeling that all true mathematicians recognize.' while talk of beauty in mathematics may be commonplace, however, the notion of mathematical beauty raises serious questions. how, exactly, should we conceive of the character of such beauty? in what sense can we meaningfully speak of the objects of mathematical investigation as appealing to us aesthetically? is beauty a property of mathematical objects or statements, or is it a subjective response particular to the perspective of the mathematician? how, in sum, are we to make sense of judgments concerning the beauty of mathematics? my aim in this paper is to show that kant's philosophy provides the resources for a compelling answer to these questions. more specifically, i argue that on the kantian account i develop beauty in mathematics is a non-conceptual response felt in light of our own creative activities involved in the process of mathematical reasoning. this proposal may come as a surprise. for, according to the standard conception, kant's aesthetics leaves no room for beauty in mathematics. this is because kant claims that judgments of beauty are essentially concerned with feeling and non-conceptual reflection rather than rational cognition, while such cognition is, on the face of it, the aim of mathematics. indeed, kant himself draws some strikingly negative conclusions concerning the possibility of beauty in the mathematical and physical sciences, claiming in the critique of judgment that there is 'no beautiful science, but only beautiful art'. in light of this, many conclude that the kantian has little of interest to say about beauty in mathematics and the sciences more broadly. as a recent commentator summarises, kant 'famously breaks with tradition in declaring that there can be no "beautiful science", nor a "science of the beautiful", because the pleasure that is characteristic of the free play of the faculties in reflective judgment [of beauty] is not to be found in the exercise of determinative judgment in science'. in the following, i aim to show that this standard conception overlooks an important insight offered by the kantian position. in particular, i suggest that the kantian proposal i develop provides a promising alternative to widespread platonist convictions that can be found among many mathematicians. according to the platonist approach, the experience of mathematical beauty is a particular intellectual insight into fundamental structures of the universe. the distinctive kantian proposal i advance in this paper, by contrast, consists in the view that the experience of beauty in mathematics is grounded not in an intellectual insight into particular properties of mathematical objects but in our felt awareness of the imaginative processes that lead to mathematical knowledge. the kantian account i propose thus offers to elucidate, as the platonist approach does not, the connection between aesthetic reflection, creative imagination and mathematical cognition. in order to argue for these claims, i focus on a surprisingly under-studied section of kant's critique of judgment. in § kant makes three key claims concerning the possibility of beauty in mathematics: (i) it is because of their unexpected purposiveness for cognition that the properties of mathematical objects are customarily regarded as beautiful. (ii) contrary to this customary conception of the beauty of mathematical properties, the purposiveness of mathematical properties does not indicate beauty but a form of perfection. (iii) while mathematical properties themselves are not beautiful, it is the demonstration of such properties that can be the object of aesthetic appreciation. in the first two of these statements, kant comes back to the reasons, spelt out in detail in the body of the 'critique of aesthetic judgment', for arguing against a conception of mathematical objects and their properties as beautiful. in the third claim, however, kant seems to retract from an outright rejection of the possibility of aesthetic experience in mathematics. kant's position, this suggests, is more complex than one might expect upon first consideration. but how should we understand the qualification made in (iii)? in what sense can mathematical demonstrations, but not the properties of mathematical objects, be regarded as beautiful? to answer these questions, i focus on kant's three claims in order. in section , i examine the type of purposiveness displayed by mathematical objects that, according to (i), is commonly regarded as the ground of beauty. i show that, according to kant, mathematical objects display a formal and objective purposiveness insofar as they are conducive to solving mathematical problems without having been designed for the solution of those problems. section discusses the reasons why mathematical objects that are purposive in this way cannot, according to (ii), be regarded as beautiful but must rather be considered as displaying a kind of perfection. as i spell out in this section, reflection on the purposiveness of mathematical objects can only ever lead to cognitive claims about those objects, but not to non-conceptual judgments that are the grounds of aesthetic pleasure. in sections and , i then tackle the difficult question of how, according to (iii), we may nevertheless conceive of beauty in mathematical demonstrations. thus, in section , i show that what kant allows as a 'rightful' (cj, v ) feeling of admiration in mathematics is a response to the surprising fit of our intellectual capacities involved in mathematical proofs. in particular, i suggest that on kant’s account we feel a sense of admiration in light of the harmony we experience between our imaginative combination of the sensory manifold and our conceptual understanding of mathematical objects and their properties. moreover, i argue in section that this feeling of admiration can adequately be identified as an aesthetic response. for, as i show, in providing non-conceptual sensory unities, the imagination makes a distinctive contribution to the process of demonstrating mathematical claims. the experience of beauty in mathematics, i thus claim, consists in an emotional response to this free and non-conceptual imaginative activity involved in mathematical proofs. i conclude, in the final section, by raising two questions about the scope of the kantian account developed in this paper and by offering a suggestion for how this account may be extended beyond certain limitations of kant's theory of mathematics. i propose that understanding the experience of beauty in mathematics as a non-conceptual response generated by our own intellectual processes sheds new light on the phenomenon of mathematical beauty. . the formal purposiveness of mathematical objects in § of the critique of judgment, kant distinguishes the formal objective purposiveness of mathematical objects, such as geometrical figures and numbers, from the formal subjective purposiveness with which he is concerned in the 'critique of aesthetic judgment', on the one hand, and, on the other, from the material objective purposiveness that is the main concern of the 'critique of teleological judgment'. the purposiveness of mathematical objects, kant argues, consists in their conduciveness to solving 'a host of problems' in a way that appears surprisingly simple (cj, v ). consider the geometrical figure of a circle, for instance. it is by means of this basic figure that we can solve the apparently difficult task of 'construct[ing] a triangle from a given baseline and the [right] angle opposite to it' (ibid.). while an infinite number of different solutions could be given to the problem, the circle that takes the baseline of the triangle as diameter provides one unified solution. it presents precisely that geometrical shape that contains all the missing points required for constructing a right-angled triangle. thus, by means of the simple figure of a circle we can encompass all possible solutions to the problem. it is in this sense that mathematical objects, as kant argues, display 'a manifold and often admired [...] purposiveness' (ibid.). kant characterises the purposiveness thus attributed to mathematical objects as 'an objective purposiveness which is merely formal' (ibid.). the purposiveness is objective because it is a relation between objects, for example between the geometrical figures of circles and right-angled triangles. this contrasts with the subjective purposiveness of the objects of aesthetic appreciation, which stand in a purposive relation to the subject. as kant explains in the 'analytic of aesthetic judgment', the objects of aesthetic appreciation are subjectively purposive insofar as our cognitive faculties, by reflecting on the form of these objects, are 'unintentionally brought into accord' (cj, v ) with one another. moreover, the purposiveness of mathematical objects is 'formal' (ibid.) since, although the objects are conducive to the solution of various problems and thus have the form of purposiveness, they have not in fact been created for the solution of those problems. this contrasts with the 'material' (cj, v ) purposiveness of objects that can only be conceived as the realisation of an intended purpose, which is 'the cause of the [object] (the real ground of its possibility)' (cj, v ). the purposiveness of the properties of a circle for constructing right-angled triangles thus differs from that of the properties of an artefact, such as a garden, for example, whose parts (e.g. trees, flower beds, and paths) have intentionally been designed and arranged so as to constitute a garden of a particular shape. it is because mathematical objects display the form of purposiveness, even though they have not been designed for the realisation of any particular purpose, that, as kant argues, their purposiveness is 'not expected from the simplicity of their construction' (cj, v ) and may, for that reason, surprise us. moreover, it is because of this unexpected purposiveness that, as kant claims further, the properties of mathematical objects are commonly described in aesthetic terms: (i) it is customary to call the properties of geometrical shapes as well as of numbers […] beauty, on account of a certain a priori purposiveness, not expected from the simplicity of their construction, for all sorts of cognitive use, and to speak of this or that beautiful property of, e.g., a circle, which is discovered in this way or that (cj, v f.). kant explicitly attributes this view to plato, but also seems to have in mind the perfectionist conception, put forward by such rationalist thinkers as christian wolff, alexander gottlieb baumgarten and georg friedrich meier, and going back to leibniz, which identifies beauty with the perception of some form of objective purposiveness in the object (or, alternatively, in the artistic representation of the object). according to this conception, our experience of beauty consists in the sensory recognition that the perceived object displays a certain internal unity and harmony and a conduciveness to purposes. while proponents of this conception may have held different views about the precise nature of such recognition of perfection, they agree on the key claim that the experience of beauty is, at least in part, based on the experience of a property of purposiveness in the object itself. insofar as this objective purposiveness is something that can be known in the object, kant also calls it an 'intellectual' purposiveness, that is, a purposiveness that 'is cognised through reason' (cj, v ). as he critically points out, it is the recognition of such – often unexpected and hence surprising – objective and intellectual purposiveness that is commonly associated with the experience of beauty in mathematical objects. . relative perfection rather than intellectual beauty kant crucially disagrees with the 'customary' view presented in (i). on his account, there is an important difference between the objective formal purposiveness we find in mathematics, on the one hand, and the subjective formal purposiveness that can be the ground of an experience of beauty on the other: (ii) it is not an aesthetic judging by means of which we find them [i.e., the properties of mathematical objects] purposive, not a judging without a concept, which makes noticeable a merely subjective purposiveness in the free play of our cognitive faculties, but an intellectual judging in accordance with concepts, which gives us distinct cognition of an objective purposiveness, i.e., serviceability for all sorts of (infinitely manifold) purposes. one would have to call it a relative perfection rather than a beauty of the mathematical figure (cj, v ). kant agrees with the rationalists that the objective purposiveness of mathematical objects may be called a kind of perfection, that is, a perfection relative to the instantiation of a type, or the realisation of a purpose. he importantly disagrees with the further claim, however, that the perception of such relative perfection constitutes an experience of beauty. rather than consisting in the perception of some purposiveness in the object, the experience of beauty, for kant, is the awareness of a purely subjective purposiveness that is independent of any conceptual cognition of the object. in contrast with our experience of the objective purposiveness of mathematical objects, the experience of beauty is not identifiable with any conceptual representation of purposiveness but can be perceived only through feeling. in order to understand this claim, it is necessary to consider kant's general views about aesthetic pleasure. as kant explains in the 'analytic of aesthetic judgment', the objects of aesthetic appreciation can be regarded as subjectively purposive insofar as, in reflecting on such objects, our cognitive faculties are brought into harmony with one another, a harmony that is experienced as aesthetically pleasing. what is important about this harmonious interaction of the faculties is that it conforms to the general conditions of cognitive judgment without, however, leading to cognition. successful cognitive judgments, on kant's account, depend on the work of the imagination, the capacity to combine different sensible states and to be aware of such combination as a unity, and the understanding, the conceptual capacity by means of which we make sense of such unity as a unity of a specific sort. cognition is thus made possible, kant argues, by an imaginative synthesis of the sensory manifold, which is subsumed under concepts by the understanding. aesthetic judgments, by contrast, differ from such cognitive judgments insofar as they do not lead to any conceptual subsumption of the synthesis brought about by the imagination. while the imagination unifies the sensory manifold in a way that could in principle be brought under concepts by the understanding, no concept is in fact applied. kant describes the interaction of imagination and understanding in such judgments as harmonious insofar as it is in accordance with the conditions of cognition in general. it can nevertheless be regarded as free and spontaneous insofar as the creative activity of the imagination, which 'gathers' and 'unites' elements of the sensory given, is unconstrained by the conceptual guidance and determination of the understanding (cpr, a f./b ). the resulting judgment remains purely reflective, that is, it consists in the free and non-conceptual consideration of the object without, however, leading to any determinate conceptual claim about the object. it is this attunement of our cognitive faculties in the face of beautiful objects, independent of any specific judgment about the object itself that, kant argues, we experience as aesthetically pleasing. in regarding an object as beautiful, he claims, 'we are conscious' of the harmony of our intellectual capacities 'with the sensation of satisfaction' (cj, v ). in contrast with the rationalists, kant thus conceives of aesthetic judgments as only indirectly concerned with the object regarded as beautiful. rather than consisting in determinate claims about some purposive property in the object, aesthetic judgments express the awareness of the free and creative activity of our own mental capacities, triggered by consideration of the object. aesthetic judgments may thus be regarded as expressions of our feeling that something makes sense to us, where this feeling of making sense is only indirectly related to the objects thus experienced and directly connected with the harmony of own intellectual activities that we experience in the face of such objects. it is in this sense that beautiful objects may be regarded as subjectively and formally purposive – purposive, that is, for our intellectual capacities without, however, fulfilling any particular purpose that can be ascribed to the object. on kant's account, the subjective purposiveness appreciated aesthetically through feeling thus differs significantly from the objective purposiveness grasped cognitively in mathematical objects. it is for this reason that kant rejects the rationalist view that identifies the objective purposiveness of mathematical objects with the ground of an aesthetic appreciation. as we have seen, kant argues that the objective purposiveness of mathematical objects and their properties must be conceived as a 'relative perfection' (cj, v ). this relative or, as kant also calls it, 'external' (cj, v ) perfection of an object consists in its 'utility' (ibid.) or 'serviceability' (cj, v ) for some external purpose, that is, for the solution of mathematical problems. a judgment on the perfection of mathematical objects, rather than consisting in free and non-conceptual reflection, ascribes concepts to objects in a determinate way. thales' theorem, for instance, gives a conceptual account of the relation between the circle and the infinite number of right-angled triangles that have the diameter of the circle as their base. when, in mathematics, we feel pleased at the sight of a simple geometrical figure that aids the solution of a complex problem, the pleasure thus generated cannot, therefore, be a type of aesthetic appreciation. it is brought about not by the 'free and indeterminately purposive entertainment of the mental powers with that which we call beautiful' but by 'the approval of the solution that answers a problem' (cj, v ). hence, judgments about the relative perfection of mathematical objects, kant concludes, are not identifiable with aesthetic judgments but are concerned with a type of intellectual pleasure. indeed, kant leaves no room for ambiguity in distinguishing the two types of pleasure when he argues that '[t]he designation of an intellectual beauty cannot legitimately be allowed at all, for otherwise the word “beauty” would have to lose all determinate meaning' (cj, v ). the appreciation of beauty, in short, has nothing to do with the satisfaction associated with the solution of intellectual problems. the rationalists fall into error, kant concludes, when they mistake intellectual for aesthetic pleasure in their analysis of our experience of mathematical objects. . admiration for mathematical demonstrations after rejecting the rationalist, or 'customary', view that ascribes aesthetic qualities to the purposive properties of mathematical objects, kant makes his surprising third claim in which he appears to retreat from an outright rejection of aesthetic considerations in mathematics. as kant goes on to argue, (iii) [o]ne could rather call a demonstration of such properties beautiful, since by means of this the understanding, as the faculty of concepts, and the imagination, as the faculty for exhibiting them a priori, feel strengthened (which together with the precision which is introduced by reason, is called its elegance): for here at least the satisfaction, although its ground lies in concepts, is subjective, whereas perfection is accompanied with an objective satisfaction (cj, v ). kant's claim raises a number of questions. why should mathematical demonstrations but not mathematical properties be called beautiful? what exactly is the difference between mathematical properties and their demonstration that makes the latter, but not the former, suitable for aesthetic consideration? and, more specifically, why do the demonstrations of mathematical properties rather than the properties themselves elicit a subjective rather than objective satisfaction, as they would have to, if the satisfaction at issue is genuinely aesthetic? on initial consideration, one might be tempted to construe kant as suggesting that only mathematical demonstrations loosely speaking can be regarded as beautiful. that is, when kant speaks of a 'demonstration of mathematical properties' one might understand him as referring to some kind of representation of mathematical objects and their qualities. according to this reading, the depiction of circles and triangles in paintings or their display on the facade of buildings, for example, could be judged aesthetically. thus, one might argue that we can reflect on the outer form or shape of such objects aesthetically while abstracting from any conceptual representations, for instance their conduciveness to mathematical problem solving. representations of geometrical figures such as circles and triangles would then be regarded as the object of non-conceptual reflection that grounds an aesthetic pleasure. this reading is tempting, i think, because kant suggests that a pure judgment of taste is possible even in the case of an object for which we have a determinate concept, 'if the person making the judgment [...] abstracted from it [i.e. the concept] in his judgment' (cj, v ). kant thus leaves room for the possibility of non-conceptual, aesthetic judgment by abstracting from concepts that may otherwise be the basis of determining judgments about the object. as a reading of the above passage, however, this initial proposal is unconvincing. kant never uses the term 'demonstration' (demonstration) in the loose or non-technical sense as referring to a representation of some form or other. rather, he unambiguously employs the term in order to denote 'a proof which is the ground of mathematical certainty' (logic, ix ), as he defines it in the logic lectures. kant's third statement, then, is not concerned with representations of mathematical objects such as geometrical shapes on wallpapers, but with mathematical proofs. far from focussing on judgments that abstract from concepts, and hence from cognitive claims, kant is concerned with proofs that are the very basis of mathematical cognition. but this only raises the questions with which we were confronted above in a new form. for why should kant allow for the aesthetic appreciation of mathematical proofs if he so adamantly rejects judgments of beauty about mathematical objects and their properties? i suggest that in order to answer this question we need to pay closer attention to the specific character of mathematical proofs on kant's account. since mathematical certainty, for kant, is intuitive certainty, he also characterises a demonstration in the critique of pure reason as 'an apodictic proof, insofar as it is intuitive' (cpr, a /b ). this is important for understanding kant's difficult third claim. indeed, i think that if we take account of the intuitive nature of mathematical demonstrations, we can explain kant's conception of beauty in mathematics. a closer look at what kant says in § about the admiration we may experience for mathematical reasoning will begin to throw light on the connection between the intuitive character of mathematical demonstrations and the aesthetic appreciation of mathematics. having described how, in the history of mathematics, the geometers 'delighted' in the purposiveness of geometrical figures, kant points out that this purposiveness may arouse in us a sense of admiration: for in the necessity of that which is purposive and so constituted as if it were intentionally arranged for our use, but which nevertheless seems to pertain originally to the essence of things, without any regard to our use, lies the ground for the great admiration of nature [...] (cj, v ). kant suggests that we experience a sense of admiration when objects seem to us as if they were created for the realisation of our purposes, yet are not in fact so created. this general account of admiration, however, immediately raises a question about the particular case of our admiration for mathematical objects. in the case of natural objects whose origin is independent of our purposes, it is indeed unsurprising that we may feel a sense of astonishment if those objects turn out to be conducive to our purposes. and yet, the case of mathematical objects is different insofar as these objects, as kant also argues, are products of the human mind. they are not things whose character is contingent and discovered by us only empirically, but objects whose particular nature is determined by a priori concepts. this is why objects of mathematics can be constructed, that is, exhibited in a priori intuition. we can, in other words, produce sensible representations of mathematical concepts without recourse to any particular experience. thus, while it may, of course, be true that we do not always construct mathematical objects in order to solve certain problems in mathematics, it is not obvious why we should be astonished at their apparent fit with the needs of human reason. for, in so far as they are the products of our own intellectual activity, they cannot but be in conformity with, and in this respect also purposive for, that activity. it seems, rather, that in the case of mathematical objects we ourselves 'introduce the purposiveness into the figure that [we] draw in accord with a concept' (cj, v ). why, then, should we be surprised by, and indeed feel admiration for, the apparent purposiveness of objects that we have constructed ourselves? even though mathematical objects are products of the human mind, kant claims that they nevertheless elicit a 'rightful' (cj, v ) sense of admiration in us. i believe that what is important for understanding this experience of admiration is not, as kant first seems to suggest, that we may mistake the a priori rules of construction for empirical ones. what is important is rather that, on kant's account, mathematical construction and, indeed, demonstrations that rely on such construction are dependent on intuition. in order to understand why we may feel a sense of admiration in mathematics, we thus need to appreciate kant's characterisation of mathematical knowledge as synthetic a priori. although the concept of a circle, for instance, is an a priori concept, kant argues that we cannot know of the particular properties of the circle and its conduciveness to the solution of difficult mathematical problems without constructing it in a priori intuition: the many rules, the unity of which (from a principle) arouses this admiration, are one and all synthetic, and do not follow from a concept of the object, e.g., from that of a circle, but need this object to be given in intuition (cj, v ). similarly, 'curves yield […] purposive solutions that were not thought of at all in the rule that constitutes their construction' (cj, v ). we therefore cannot, according to kant, infer the properties of a circle or a curve that are conducive to the solution of geometrical problems analytically but only synthetically by recourse to intuitive representation. and it is this dependency on intuition, i suggest, that ultimately grounds the experience of admiration in mathematics on kant's account. what, then, is it about the a priori synthetic nature of mathematical constructions and demonstrations that elicits such admiration? given kant's conception of mathematics, what is special about mathematical objects is not that they appear to us as if they were designed even though they are not. what generates surprise is rather that, through reflection on such objects, our conceptual understanding is in fact purposefully aided by the activities of imagination. even against the background of kant’s critical conception of mathematical objects as products of the human mind, it is astonishing that we can construct these objects in pure intuition and, by reflecting on them, extend our knowledge of them and their relation to other mathematical objects purely a priori. what is surprising, in other words, is the unlikely fit of the knowledge gained through sensible representations in a priori intuition 'with the principles already grounded in the mind', that is, our conceptual understanding of the object (ibid.). what provokes surprise, then, is not simply the fact that geometrical figures or numbers are conducive to the solution of a host of difficult mathematical problems. what evokes astonishment is rather, more generally, that in mathematical demonstrations we can solve difficult conceptual problems by recourse to a priori sensible representation. it is this 'harmony' between our concepts given by the understanding and 'space, by the determination of which (by means of the imagination, in accordance with a concept) the object is alone possible' that is made evident in mathematical proofs (cj, v ). and it is this harmony, i suggest, that is the ground of our admiration in mathematics. returning to the passage in which kant characterises his general conception of the admiration of nature, it is then important not to overlook a final qualification of this conception: for in the necessity of that which is purposive and so constituted as if it were intentionally arranged for our use, but which nevertheless seems to pertain originally to the essence of things, without any regard to our use, lies the ground for the great admiration of nature, not outside of us so much as in our reason' (cj, v ; italics added). what is considered as worthy of admiration, in the end, is not so much the nature of things in the external world but rather our own intellects. in the specific case of mathematics, it is not the objects of mathematics and their properties but our own intellectual capacities involved in mathematical demonstrations, understanding and imagination, that elicit in us a sense of admiration. the admiration we feel in mathematics is thus only indirectly a response to a particular proof, and directly linked to the fit of our conceptual capacity with the capacity of imagination. . beauty in mathematical demonstrations as kant argues in § , we naturally feel a sense of admiration in mathematics, not because of a formal purposiveness of mathematical objects for problem solving but because of the surprising harmony of our intuitive and conceptual capacities. does this account help to answer the questions raised in the previous section about kant's third claim? in particular, should the admiration we may feel in the face of mathematical proofs really be characterised as an aesthetic response? kant's account of admiration in mathematics shows some obvious dissimilarities with his account of the appreciation of beauty. indeed, these dissimilarities may lead one to suspect that the former should not be identified with the latter. while aesthetic judgment is non- conceptual, in mathematical constructions the imagination provides a priori representations of concepts. moreover, even though mathematical proofs are the basis of intuitive certainty, they also lead to conceptual cognition. while the proof of thales' theorem, for example, relies on intuition, this intuition itself grounds the knowledge that all points on the circle are the missing points of all possible right-angled triangles. one might therefore think that the harmony of imagination and understanding, occasioned by mathematical demonstrations, is not the harmony of free play, but rather the harmony associated with cognitive judgments, and judgments of perfection in particular, a harmony brought about by the guidance of a determinate concept. and yet, while mathematical demonstrations are ultimately the ground of determinate knowledge claims, on kant's account the imagination must nevertheless make a spontaneous and non-conceptual contribution to the processes that lead to such knowledge. as we have seen in the previous section, according to kant it is through a priori intuitive representation that we gain insight into the properties of mathematical objects that could not be analytically inferred from their concepts. this process begins with the construction of an object according to a concept and ends with the cognitive judgment that the object has such-and-such properties. it is in between these two acts, i suggest, that the imagination makes a contribution that is free from conceptual determination. in order to substantiate this claim, we need to look more closely at the role imagination plays in learning something new about mathematical objects that was not entailed 'in the rule that constitutes their construction' (cj, v ). thus, in mathematical construction the imagination produces a representation in a priori intuition that provides an instance of a mathematical concept. while the result is an 'individual object', the construction nevertheless provides a 'universal' representation of all those objects that fall under the concept (cpr, a /b ). it does so by representing the rule-governed 'act of construction' (cpr, a /b ) or, as kant puts it in the 'schematism' chapter of the first critique, the 'universal procedure' of producing the object (cpr, a /b ). this characterisation of construction in mathematics indicates that the imagination, while generating non-conceptual and intuitive unities, does so in accordance with concepts. mathematical demonstrations do not, however, end but begin with the construction of mathematical objects. it is only through subsequent reflection on these objects that we can find out about their further properties such as, for example, the relation between a circle and right-angled triangles. subsidiary steps are thus required in order to prove a mathematical claim. it is at this point, i suggest, that the activity of the imagination makes its original contribution. insofar as mathematical knowledge is, on kant’s account, synthetic a priori, the subsidiary steps in a proof can consist neither in the analysis of the mathematical concepts thus instantiated nor in simply reading off hitherto unknown properties from empirically given data. rather than constructing an intuitive representation of what was already analytically entailed in the original concepts, and rather than considering sensory data provided to us empirically, the imagination spontaneously offers sensory unities that are produced independently of the determination of conceptual rules. we may think of this as imaginatively playing around with the mathematical objects constructed in a priori intuition before, subsequently, recognising – conceptually – that they have particular properties or stand in certain relations to one another. the possibility of making the next step in a proof, i suggest, is grounded in this free play of our imaginative activities that offer different ways of combining the sensory manifold by, for instance, drawing new connections between mathematical objects that were not originally thought in the concepts of those objects. in the proof of thales' theorem, for example, we start by constructing a circle and a triangle whose three points a, b and c lie on the circle and whose baseline ac is a diameter of the circle. subsidiary steps involving auxiliary principles and constructions are then needed in order to prove the theorem. thus, we can show that by dividing the triangle through a line drawn from the centre of the circle to point b, we obtain two isosceles triangles, that is, triangles whose base angles are equal. this turns out to be a crucial move in the demonstration, which enables us, by operations of addition and division, to prove that abc is a right angle. that the construction of two isosceles triangles will turn out to be a useful step in the proof cannot be known in advance, however. as béatrice longuenesse points out, the capacities involved in choosing the next step in a proof should rather be understood in the context of kant's famous notion of 'mother wit'. on this conception, the choice of intermediary steps in a proof depends for kant 'on that particular aspect of the power of judgment' which is 'a talent that no learning of scholarly rule can replace'. that is, the choice of intermediary steps is not learnt, or deduced from given principles, but is dependent on one’s aptitude for making the right judgment. this proposal hints at the irreducible originality of the choice of moves that lead to the discovery of a proof in mathematics. i believe, however, that the capacity for judgment, or mother wit, ultimately relies on the contribution made by the free activity of the imagination. for the ability to make the right judgment consists precisely in recognising that a universal principle or concept is suitable for subsuming a particular given in sensibility. it is the imagination, i suggest, which first produces sensible unities in light of which the use of an auxiliary principle, such as the principle that all isosceles triangles have equal base angles, will appear more or less adequate. rather than picking randomly between a set of principles, which are then presented in concreto through constructions in a priori intuition, in mathematical demonstrations we first produce sensible unities in imagination, which are subsequently subsumed under suitable principles. that is, free from the guidance of concepts, we imaginatively play around with the sensory manifold, combining and recombining it with the unities already constructed, thereby offering new intuitive unities to be recognised as falling under conceptual rules. in spontaneously offering new combinations of the sensory manifold in a priori intuition, the imagination thus makes possible the instantiation of subsidiary principles required for proving such mathematical claims as thales’ theorem. in this way we can arrive at a proof, conceptually spelt out as a series of inferences. but we do so only insofar as the imagination has already provided us with sensible unities that were not originally thought under the concepts with which we started. the presentation of a 'chain of inferences' (cpr, a /b ), in other words, is possible only retrospectively and as a systematic presentation of a mathematical proof already discovered. the intellectual processes involved in the original discovery of the proof by the mathematician – as well as the subsequent recreation of such discovery processes by the mathematics student – however, are 'guided by intuition' (ibid.) and essentially involve the free activity of the imagination. if this suggestion is correct, then the cognition achieved through mathematical proofs is made possible by a spontaneous act of the imagination. just as in aesthetic judgment, in mathematical demonstrations the imagination acts freely, unconstrained by, and yet in harmony with, the understanding. it would follow that the resulting fit between the spontaneity of the imagination, on the one hand, and the conceptual determination of the understanding, on the other, is itself undetermined by further conceptual rules and can therefore be regarded as free. there is, in other words, no further rule that can account for the harmony between the imaginative production of synthetic unities in a priori intuition and the conceptual cognition to which our imaginative activity leads. it is for this reason, i believe, that kant describes the harmony of imagination and understanding in this context as ultimately 'inexplicable' (cj, v ). indeed, it is because of our astonishment at the inexplicable fit between intuition and understanding that, as kant claims, we are led to 'have a presentiment [ahnen] of something lying beyond those sensible representations, in which, although unknown to us, the ultimate ground of that accord could be found' (cj, v ). even though we neither can nor need to know about this ultimate ground, we are evoked to think of it as the condition of possibility of the agreement of our cognitive faculties. insofar as the harmony that is taken to lie in such an unknowable ground is itself inexplicable, moreover, it cannot be the source of an intellectual pleasure. the pleasure thus occasioned by mathematical demonstrations cannot be identified with that elicited by the discovery of a solution to a problem but consists in a subjective pleasure, a satisfaction felt in response to the inexplicable fit of imagination and understanding. can the pleasure experienced in response to mathematical demonstrations then be classed as an instance of aesthetic appreciation? as we have seen, kant's account of admiration in mathematics shows some striking similarities with his account of the appreciation of beauty. in both cases, we encounter a surprising fit of our intellectual capacities. the pleasure that is expressed in judgments of taste arises as a result of an unexpected agreement that we experience between formal aspects of the object and the requirements of our cognitive faculties. similarly, in the case of our feeling of admiration for mathematical demonstrations, we experience an unexpected agreement between our imaginative play with the sensory manifold in a priori intuition and the conceptual insight gained thereby. in the case of aesthetic judgment, kant describes this harmony of the faculties as leading to an 'animation' or 'quickening' [belebung] 'of both faculties (the imagination and the understanding)' (cj, v ). similarly, in the case of mathematical demonstrations, kant argues that in their interaction imagination and understanding 'feel strengthened' (cj, v ). in both cases, the objects of appreciation may be considered as subjectively purposive, that is, as purposive for our intellectual capacities. in both cases, it is not the objective purposiveness of the objects themselves, but the subjective purposiveness we become aware of, respectively, on the occasion of mathematical demonstrations and beautiful objects that is the source of our admiration. and in both cases, finally, we are led to an intimation of the super-sensible as a ground of the marvellous harmony of our intellectual capacities. according to these parallels, the admiration we may feel in the face of mathematical proofs can thus quite plausibly be regarded as an aesthetic appreciation. for although mathematical demonstrations lead to determinate judgments about mathematical objects that leave no room for the free play of the imagination, what elicits the experience of beauty in mathematics are not those objects or their properties themselves, or indeed their conduciveness to the solution of mathematical problems, but rather the free activity of our intellectual faculties that is employed in mathematical demonstrations. on kant's account, judgments about the beauty of mathematical proofs, i therefore suggest, are a form of aesthetic judgment grounded in the creative process of the imagination that leads to such knowledge. . conclusion the foregoing discussion sheds light on the question of what, from a kantian position, can be said about beauty in mathematics. for kant, beauty is not a feature attributable to mathematical objects and their apparently purposive properties, but is experienced rather in the process of demonstrating mathematical theorems through a creative act of the imagination. insofar as this creative activity involves the free and spontaneous use of imagination which, though unconstrained by conceptual rules, nevertheless leads to conceptual insight, it points to the fit between our intellectual capacities. and it is the awareness of this fit that, on kant's account, is experienced with a feeling of pleasure. thus, the experience of mathematical beauty, according to this account, does not consist in a response to the surprising applicability of our mathematical concepts and theorems to empirical reality. instead, it is generated by the awareness that our capacities for imaginative synthesis fit together with our conceptual capacities in a way that makes it possible for us to learn something genuinely new about a priori concepts by pure acts of imagination. it is the awareness of this harmony, elicited by the process of mathematical demonstration rather than the finished product, that is the basis of aesthetic experience in mathematics on kant's account. a discussion of the statements presented in § of the critique of judgment thus shows that kant is indeed justified in making his rather suggestive claim (iii) in which he allows for a qualified conception of beauty in mathematics. the kantian position draws out, in particular, the inherent connection between the creativity of mathematical proofs and the attribution of beauty to such proofs. and yet, this conclusion also raises a number of questions concerning, first, the scope of the kantian proposal within the context of kant's theory of mathematics and, second, the possibility of extending the kantian suggestion beyond kant's transcendental philosophy. i shall raise two such questions, before concluding with a suggestion for how the kantian account i have proposed might be developed further. first, one may wonder whether the proposed conclusion is equally valid, on kant's account, for different areas of mathematics. while in the critique of judgment kant speaks of mathematical objects in general, and explicitly refers to geometrical figures and numbers, his discussion of mathematical beauty focuses on geometry rather than arithmetic. this accords with a related asymmetry between kant's discussion of geometry and arithmetic in the critique of pure reason. what is important about this asymmetry is that kant seems to provide different accounts of the dependency on intuition of geometry on the one hand and arithmetic on the other. more generally, commentators have disagreed about whether for kant all mathematical proofs are equally dependent on intuition. that is, they have disagreed about whether intuition is required only for the construction of mathematical objects and the evidence of the truth of the axioms, or also for moving between the individual steps of a proof. settling such disagreement is beyond the scope of the present discussion. that the disagreement exists may nevertheless be cause for concern for the kantian account of mathematical beauty i have offered. for if some mathematical proofs are not dependent on intuition, and hence do not require the creative involvement of imagination as i have suggested, then such proofs cannot, on kant's theory, elicit an aesthetic response. beauty could only be found in proofs where the imaginative synthesis of intuitive content is experienced as freely harmonising with conceptual understanding. such a restriction of mathematical beauty to some mathematical demonstrations, however, would seem altogether arbitrary and incompatible with the actual phenomenology of aesthetic pleasure in response to mathematical proofs. what, then, is the scope of kant's account of mathematical beauty within the wider context of his theory of mathematics? second, one may wonder how far it is possible to extend the kantian proposal beyond kant's own account of mathematics. for, independently of the question of how to read kant's conception of the importance of intuition in mathematical demonstrations, few mathematicians today would want to ascribe as extensive a role to intuition as did kant. even if one does not adhere to a strictly logicist conception of mathematics as reducible to logic, or to a strictly formalist account of higher mathematics as concerned with statements that are nothing more than uninterpreted strings of symbols, it is undeniable that many mathematical proofs work without recourse to intuition. again, it would seem ad hoc to rule out in principle, as the kantian position appears to do, the possibility of ascribing beauty to mathematical proofs that are far removed from anything that can be represented intuitively. can the kantian account of mathematical beauty tell us anything more general about aesthetics in mathematics, including attributions of aesthetic features to purely formal demonstrations? while a detailed treatment of these questions centring on kant's controversial account of the synthetic a priori status of mathematics will have to be deferred to another occasion, i would like to end by suggesting a way in which the kantian proposal may be extended to contemporary discussions. as we have seen, the crucial insight of the kantian account is that the experience of beauty in mathematics presents a non-conceptual response felt in light of our own creative imaginative activities involved in mathematical demonstrations. a more general lesson to be learnt from the kantian account is possible, i believe, if we understand the creative practices and reasoning processes in mathematics that elicit an aesthetic response in a wider sense than the one proposed by kant's account of our intellectual faculties. more specifically, our mathematical practices and reasoning processes may go beyond what kant describes as the free and harmonious activity of the faculties of imagination and understanding and include, for instance, the interaction of visual and conceptual thinking as well as the purely formal manipulation of symbols. even where intuitive representation in the kantian sense is not necessary for mathematical demonstrations, visual representation may nevertheless guide mathematical thinking. visual representations may, for instance, provide alternative evidence for, and indeed first suggest, a mathematical theorem that can also be proven purely formally. it seems plausible that, in such a case, the experience of beauty is a response to our awareness of the creative activity of visual representation, which is subsequently recognised as fitting our conceptual understanding of the theorem. moreover, in cases where mathematical proofs cannot be related to intuitive representation at all, and where only a purely formal proof of a theorem is possible, the discovery of such a proof may nevertheless involve reasoning processes that can be regarded as original and creative rather than governed by conceptual rules. in other words, while the mathematical proof may be strictly formal, the way in which the mathematician first came to think of it may not. in such a case, it still seems plausible to suggest that it is our awareness of the apparent creativity of thought in the actual practice of mathematics that can be appreciated aesthetically. extending the kantian account of beauty in mathematics in the proposed direction promises to offer resources for a robust account applicable beyond the limits of the kantian starting point. according to this account, mathematical beauty turns out to consist in a non- conceptual response generated by our own reasoning processes rather than a rational insight into mind-independent truths, as the platonist holds. it is the kantian characterisation of mathematical beauty as an emotional response to the creative intellectual processes that lead to mathematical knowledge, i believe, which makes sense of what seems so special about something striking us as beautiful amidst our attempts to gain mathematical cognition. angela breitenbach faculty of philosophy university of cambridge sidgwick avenue cambridge cb da uk ab @cam.ac.uk references allison, h. 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( ), a commentary on kant's critique of judgment. new york: methuen. chandrasekhar, s. ( ), truth and beauty: aesthetics and motivations in science. chicago/ london: university of chicago press. crawford, d. w. ( ), kant's aesthetic theory. madison, wisconsin: university of wisconsin press. crawford, d. w. ( ), ‘kant's theory of creative imagination’, in t. cohen and p. guyer (eds.) essays in kant's aesthetics. chicago: university of chicago press. friedman, m. ( ), kant and the exact sciences. cambridge, ma: harvard university press. giaquinto, m. ( ), visual thinking in mathematics: an epistemological study. oxford: oxford university press. gibbons, s. l. ( ), kant’s theory of imagination: bridging gaps in judgment and experience. oxford: clarendon press. giordanetti, p. ( ), ‘das verhältnis von genie, künstler und wissenschaftler in der kantischen philosophie: entwicklungsgeschichtliche betrachtungen’, kant-studien, : - . giordanetti, p. ( ), ‘objektive zweckmäßigkeit, objektive und formale zweckmäßigkeit, relative zweckmäßigkeit (§§ - )’, in o. höffe (ed.) immanuel kant: kritik der urteilskraft. berlin: akademie verlag. glynn, i. ( ), elegance in science: the beauty of simplicity. oxford: oxford university press. guyer, p. ( ), kant and the claims of taste. cambridge: cambridge university press. guyer, p. ( ), ‘ th century german aesthetics’, stanford encyclopedia of philosophy, http://plato.stanford.edu/entries/aesthetics- th-german/ hardy, g. h. ( ), a mathematician's apology. cambridge: cambridge university press hintikka, j. ( ), ‘kant on the mathematical method’, the monist, : - [reprinted in posy ( )]. kant, i. ( ff.), kants werke. preussische akademie der wissenschaften (ed.) berlin. kant, i. ( ), critique of judgment, p. guyer and e. matthews (trans.) cambridge: cambridge university press. koriako, d. ( ), kants philosophie der mathematik: grundlagen, voraussetzungen, probleme. hamburg: meiner. leibniz, g. w. ( ), 'on wisdom', in ibid., philosophical papers and letters, dordrecht: reidel (first published ). longuenesse, b. ( ), kant and the capacity to judge: sensibility and discursivity in the transcendental analytic of the critique of pure reason. princeton/oxford: princeton university press. mamchur, e. ( ), ‘the heuristic role of aesthetics in science’, international studies in the philosophy of science, : - . mcallister, j. w. ( ), beauty and revolution in science. ithaca/ london: cornell university press. mcallister, j. w. (ed.) ( ), recent work on aesthetics of science, special issue of international studies in the philosophy of science, . meier, g. f. ( ), anfangsgründe aller schönen künste und wissenschaften. halle. osborne, h. ( ), ‘mathematical beauty and physical science’, british journal of aesthetics, : - . parsons, c. ( ), ‘kant's philosophy of arithmetic’, in c. parsons (ed.) mathematics in philosophy: selected essays. ithaca/ london: cornell university press [reprinted in posy ( )]. poincaré, h. ( ), science and method, f. maitland (trans.) london: thomas nelson and sons. posy, c. j. ( ), kant's philosophy of mathematics: modern essays. dordrect/ boston/ london: kluwer. potter, m. ( ), reason's nearest kin: philosophies of arithmetic from kant to carnap. oxford: oxford university press. rota, g.-c. ( ), ‘the phenomenology of mathematical beauty’. synthese, : – . rueger, a. ( ), ‘experiments, nature and aesthetic experience in the eighteenth century’, british journal of aesthetics, : - . rueger, a. ( ), ‘kant and the aesthetics of nature’, british journal of aesthetics, : - . shabel, l. ( ), studies in history and philosophy of science, : - . shabel, l. ( ), ‘kant's philosophy of mathematics’, in p. guyer (ed.) cambridge companion to kant and modern philosophy. cambridge: cambridge university press. wenzel, h. c. ( ), ‘beauty, genius, and mathematics: why did kant change his mind?’, history of philosophy quarterly, : - . wenzel, h. c. ( ), an introduction to kant's aesthetics: core concepts and problems. malden, ma: blackwell. wigner, e. ( ), ‘the unreasonable effectiveness of mathematics in the natural sciences’, communications in pure and applied mathematics, : - . winterbourne, a. t. ( ), ‘art and mathematics in kant's critical philosophy’, british journal of aesthetics, : - . wolff, c. ( ), vernünftige gedanken von gott, der welt und der seele des menschen. halle ( th edition). young, j. m. ( ), ‘kant on the construction of arithmetical concepts’, kant-studien, : - . young, j. m. ( ), ‘kant's view of imagination’, kant-studien, : - . notes poincaré ( : ). others have gone further in arguing for the motivational function of beauty in mathematics (cf. wigner, ). similarly, many theoretical physicists, including paul dirac, albert einstein, hermann weyl and werner heisenberg, explicitly recognised mathematical beauty as one of the key motivations behind the formulation of physical theories (see chandrasekhar, : ff.). for conflicting approaches to these questions see, for instance, hardy ( ), rota ( ), and osborne ( ) and, with relevance to the physical sciences, mamchur ( ), mcallister ( ) and the collection of papers in mcallister ( ). for some striking examples of beauty and elegance in the mathematical and natural sciences see glynn ( ). see in particular critique of judgment (cj), v f., and anthropologie nachschriften, xxv and f. references to kant’s texts are made by citing the volume and page number of the academy edition (kant ff.), with the exception of the critique of pure reason (cpr), which is referred to by citing the page numbers of the original a and b versions. translations are my own, but in the case of the critique of judgment (cj) are guided by kant ( ). see, for instance, rueger ( ), koriako ( : ff.) and wenzel ( and : ff.). wenzel argues, in particular, that kant changed his mind, excluding the possibility of beauty in mathematics only in the s. cf. also giordanetti's ( ) discussion of the relationship of genius, artist and scientist in kant. it is similarly characteristic of the prevalent attitude, i believe, that other commentators on kant's account of mathematics and his conception of aesthetics simply remain silent on the question of mathematical beauty. see the collection of classic papers on kant's account of mathematics in posy ( ), as well as the influential discussions of kant's account of aesthetics in crawford ( ), guyer ( ) and allison ( ). crawford ( ) and winterbourne ( ) present exceptions in analysing the analogies between kant's accounts of mathematics and art. they do not, however, address the more specific question of the possibility of beauty in mathematics. rueger ( : ). on the prevalence of broadly platonist conceptions among mathematicians and natural scientists, see chandrasekhar ( ). according to thales' theorem, if a, b and c are points on a circle where the line ac is a diameter of the circle, then the angle abc is a right angle. i shall come back to the nature of the subjective purposiveness of the objects of aesthetic judgment in more detail in the next section. cf. wolff ( ), baumgarten ( / ), meier ( ), and leibniz ( / ). while, for wolff the aesthetic perception of perfection is only a less than optimal, sensory cognition, inferior to the rational cognition of that perfection (cf. wolff, , § ), baumgarten conceives of aesthetic experience as the result of a more complex activity of a range of mental capacities involved in the sensible representation of perfection (cf. baumgarten, / , § ). for a helpful comparison of different perfectionist accounts of aesthetics see guyer ( ). cf. kant's discussion of perfection in § of the 'critique of aesthetic judgment' (cj, v ff.). cf. cpr, a /b . these questions presuppose that kant's claim (iii) should be taken at face value. given kant's tentative formulation in the passage quoted, however, one may wonder whether he is really advocating unconditionally that we consider the demonstration of mathematical properties as beautiful, or whether he might be suggesting, more cautiously, that if – perhaps improperly – we were to speak of beauty in mathematics, then the demonstration of mathematical properties would be a more suitable object of appreciation than the properties themselves. before passing a judgment on the question of whether or not kant's claim should be taken at face value, i shall examine how much of what kant is claiming here can be justified, given his conception of aesthetics on the one hand and his account of mathematics on the other. moreover, regarding the particular passage quoted above, i believe that although kant's mode of expression is, indeed, tentative, guyer and matthews' translation (in kant ) inadequately over-emphasises kant's cautiousness when rendering 'eher würde man eine demonstration solcher eigenschaften [...] schön nennen können' as 'it would be better to be able to call a demonstration of such properties beautiful [...]' (cj, v ). unlike the translation, the german does not imply any evaluative judgment on whether or not it would be good to call mathematical demonstrations beautiful, but states that we could justifiably do so. a reading of this kind is suggested by giordanetti ( : ) who argues that kant denies the ascription of beauty to arithmetical formulas, yet allows it in the case of music, in which the relation between tones is a representation of arithmetical proportions. this reading is not only problematic given the reasons spelt out below, but it is also highly speculative. in the paragraph in which claim (iii) appears, kant is concerned with the properties of both numbers and geometrical figures but makes no mention of music. on the difficult question of the criteria for abstraction from concepts, see guyer ( : ff.). on the possibility of aesthetic judgments in the presence of conceptual judgments, see the discussion of free and adherent beauty in guyer ( : ff., and ), allison ( : ff.), and rueger ( ). a second reason that speaks against the initial reading can be found in the 'general remark on the analytic of aesthetic judgment'. there, kant argues that mathematical objects are not promising candidates for aesthetic consideration because they can be conceived only as the representation of a concept and are therefore not candidates for non-conceptual reflection (cf. cj, v ). cf. logic, ix, . similarly, in the introduction to the critique of judgment kant claims that we feel pleasure in the purposiveness we experience in the unity of nature, and displeasure in its disunity (cj, v f.). the pleasure kant refers to here is an intellectual one. it is the satisfaction produced by our finding the world to be conducive for human understanding. h. w. cassirer ( : f.) points out that the significance of this difference between the formal purposiveness of mathematical objects and the formal purposiveness of nature may strike especially the transcendental philosopher. while the purposiveness of mathematical objects can be explained by reference to their construction in conformity with the a priori principles of understanding, the purposiveness of external nature seems entirely underdetermined by those principles. as cassirer also acknowledges, however, the agreement of intuition and understanding in mathematical construction remains, in the end, inexplicable. i come back to this inexplicability in section below. see kant's discussion of construction in mathematics in the 'discipline of pure reason' (cpr, a /b ff.). one may, perhaps, be surprised if a particular mathematical explanation accounts for the character of a particular natural phenomenon rather than another. that the objects of mathematics are conducive to human understanding in general, however, seems entirely unsurprising because of their constructed nature. see kant's discussion of the applicability of geometrical principles to the trajectories of celestial bodies in prolegomena (iv ff.). kant first suggests that this admiration may be based on our mistakenly regarding the properties and rules of construction of mathematical objects as empirically given, and thus as surprisingly conducive to our own needs (cf. cj, v ). it is unclear, however, how such a mistaken conception of mathematics could ever be regarded as 'rightful' (ibid.). this error theory of admiration in mathematics therefore should not be, and in fact is not, kant's last word on the matter. a discussion of kant's argument for this characterisation goes beyond the scope of this paper. see kant's account of the method of mathematics in the 'discipline of pure reason' (cpr, a ff./b ff.) and his earlier account of the synthetic character of mathematics in his essay 'inquiry concerning the distinctness of the principles of natural theology and morality' (ii ff.). for detailed analysis of kant's account of mathematics, see the papers collected in posy ( ) as well as young ( ), friedman ( : - ), shabel ( and ) and carson ( ). how exactly we should understand this harmony of imaginative production with the concepts such production instantiates is a matter of serious controversy in the literature. commentators disagree about whether the imagination is wholly guided by concepts or, alternatively, offers a contribution that, while making concept application possible, is itself free from conceptual determination. young ( ) and allison ( ), for instance, hold that in schematising, the imagination is concept-governed, even if it does not follow conceptual rules consciously but only blindly. bell ( ) and gibbons ( ), by contrast, argue that the activity of the imagination in schematising is to be understood on the model of the free and creative imagination at work in aesthetic experience. commentators thus disagree about how much we should read into kant's famous pronouncement that the schematism is 'a hidden art in the depths of the human soul' whose activity cannot be understood or spelt out conceptually (cpr, a /b ). i cannot resolve this conflict in the present paper. while i believe that more could be said about the freedom of the imagination in this context, my argument does not hinge on the extent to which the imagination acts spontaneously in the schematism, and hence the original construction of mathematical objects. the crucial claim is, rather, that the imagination makes a spontaneous contribution to the subsequent reflection on those objects, thereby making possible mathematical demonstrations. from the fact that triangles aob and cob are isosceles triangles, and the fact that the sum of the angles in a triangle is equal to °, we know that (i) α + (α + β) + β = °. by operations of addition and division we then get (ii) α + β = °, and (iii) α + β = °. longuenesse ( : ). cf. cpr, a /b . i thus agree with crawford ( : ), and similarly winterbourne ( ), who warn against the danger of identifying the (ineffable) 'order of discovery' of a mathematical proof with the (effable) 'order of teaching or systematic presentation of truths already discovered'. this distinction does not imply, however, that beauty can be experienced only in the original discovery of the proof. for, in going through a proof presented to us, we may follow through and thus appreciate the creative thought processes that could have led to its discovery. it is the intimation of the ultimate ground of such harmony that, as kant argues, has led plato 'to the enthusiasm that elevated him beyond the concepts of experience to ideas' (cj, v ). for kant, such enthusiasm is misguided insofar as it presupposes that we can have cognitive access to ideas that are in principle unknowable. cf. also kant's more appreciative mention of plato's 'philosophical spirit', demonstrated by his 'wonderment' in the face of the great power of pure reason in geometry in the prize essay ‘what progress has metaphysics made in germany since the time of leibniz and wolff?’ (xx ). i thus disagree with wenzel's ( : ) suggestion that, on kant's account, only empirical objects can arouse in us a sense of admiration. in the case of mathematics, it is precisely our reflection on objects that can be known purely a priori which elicits in us a subjective, aesthetic response. see, in particular, the 'transcendental aesthetic' (cpr, a /b ff.) and the 'discipline of pure reason' (cpr, a /b ). see, for example, the discussions in hintikka ( ), parsons ( ) and potter ( : f.). on the prevalence and importance of visual thinking in mathematics see giaquinto ( ). for some striking examples that seem to fit this suggestion see brown ( ). in this context, the growing discussion of mathematical practice is of particular interest. cf., e.g., bueno and linnebo ( : ff.). earlier versions of this paper were presented at cambridge and st andrews, and i thank the audiences for very helpful questions and suggestions. i would also like to thank, specifically, john callanan, john collins, marina frasca-spada, nick jardine, oskari kuusela, sasha mudd, davide rizza and alexander rueger for their invaluable feedback on earlier drafts. finally, i am very grateful to the anonymous referee for this journal whose careful and constructive criticisms have significantly helped to improve the paper. - -toerien.qxd http://soc.sagepub.com sociology doi: . / ; ; sociology merran toerien and celia kitzinger beauty salon emotional labour in action: navigating multiple involvements in the http://soc.sagepub.com/cgi/content/abstract/ / / the online version of this article can be found at: published by: http://www.sagepublications.com on behalf of: british sociological association can be found at:sociology additional services and information for http://soc.sagepub.com/cgi/alerts email alerts: http://soc.sagepub.com/subscriptions subscriptions: http://www.sagepub.com/journalsreprints.navreprints: http://www.sagepub.co.uk/journalspermissions.navpermissions: http://soc.sagepub.com/cgi/content/refs/ / / citations by sandra hopps on october , http://soc.sagepub.comdownloaded from http://www.britsoc.co.uk http://soc.sagepub.com/cgi/alerts http://soc.sagepub.com/subscriptions http://www.sagepub.com/journalsreprints.nav http://www.sagepub.co.uk/journalspermissions.nav http://soc.sagepub.com/cgi/content/refs/ / / http://soc.sagepub.com emotional labour in action: navigating multiple involvements in the beauty salon ■■ merran toerien university of york ■■ celia kitzinger university of york a b s t r ac t building on hochschild’s path-breaking analysis of service providers’ ‘emotional labour’, this article demonstrates some of the interactional skills required for emo- tional labour to be performed. using conversation analysis (ca), we examine a sin- gle case from a database of recorded beauty salon interactions. the episode was chosen because it makes visible the mechanics of how a beauty therapist manages conflict between her ‘multiple involvements’ in the salon: between her simultane- ous engagement in topic talk and hair removal. we show first how she navigates this conflict and then how her actions may be understood as an example of emo- tional labour. the article addresses, then, both the feminist concern with making visible the skills of emotional labour and the conversation analytic concern with how participants manage multiple involvements in a socially meaningful way. k e y wo r d s beauty therapy / conversation analysis / emotional labour / feminist sociology introduction emotional labor emphasizes the relational rather than the task-based aspect of work found primarily but not exclusively in the service economy. it is labor-intensive work; it is skilled, effort-intensive, and productive labor. it creates value, affects productiv- ity, and generates profit. it is why frontline service workers and paraprofessionals have been referred to … as the ‘emotional proletariat’. (steinberg and figart, : ) s o c i o l o g y copyright © bsa publications ltd® volume ( ): – doi: . / sage publications los angeles, london, new delhi and singapore by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com i n her classic analysis of flight attendants’ work, hochschild ( ) first used the term ‘emotional labour’ to refer to self and other emotion management in the paid workplace. she distinguished this from ‘emotion work’: emotion management in the non-paid sphere. although this distinction has been cor- rectly criticized as simplistic (bolton and boyd, ), the act of naming ‘the often invisible dimensions of the relational work which people do as part of car- ing for their families or performing their paid jobs’ (mirchandani, : ) was path breaking. hochschild’s thinking has since been subject to extensive development (see steinberg and figart, ) and applied to numerous work- place settings: from hospice nursing (james, ) to sex work (sanders, ); from call-taking (korczynski, ) to small-business management (mirchandani, ). we focus on emotional labour in the workplace because our analytic interest is in professional beauty therapy. as the opening quote suggests, emotional labour takes skill, may be effort intensive, and has the aim of generating profit, improving workplace function- ing and/or adding value to an organization’s service. emotional labour includes the idea that many employees are ‘paid to “look nice”, smile, be caring, be polite’ (fineman, : ), and may entail an array of relational tasks, such as, ‘soothing tempers, boosting confidence, fuelling pride, preventing frictions, and mending ego wounds’ (calhoun, : ). emotional labour may involve suppressing or inducing one’s own emotions. crucially, the employee must effect whatever emotional impact is required by the organization; e.g. flight attendants must relax nervous passengers while debt collectors must intimidate (hochschild, ). emotional labour researchers have pursued diverse agendas, including, as steinberg and figart ( ) show, assessment of: (i) the effect on employees of performing emotional labour; (ii) the relationship between emotional labour and organizational effectiveness; and (iii) the extent to which emotional labour is recognized and remunerated. feminist researchers have been particularly interested in the third of these, finding emotional labour/emotion work to be useful concepts because they name ‘as work behaviours which, whether performed in the private or in the public sphere, are typically invisible and unrecognised as such’ (frith and kitzinger, : , emphasis in original). thus, although often a job requirement, emotional labour tends to be poorly rewarded (steinberg and figart, ). this is a feminist concern because, as a group, women are worse affected than men. this partly reflects women’s overrepresentation in the ser- vice industry, where emotional labour is a job requirement and pay is notori- ously poor. crucially, however, feminists have underscored the socially constructed nature of skill, showing how the tasks traditionally performed by women within the reproductive sphere are: … defined as requiring minimal skill – even though the very same tasks carried out in the productive sector, particularly if associated with male workers, are considered to require extensive training and qualifications … the ‘socially constructed’ nature of skill includes the assumption that women are born with certain ‘natural’ skills which require neither talent nor training, and which are merely part of their ‘natu- ral’, ‘feminine’ behaviour. (tancred, : ) sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com consequently, such skills are rendered invisible, and remain so even when utilized by women in their paid jobs. thus, the tendency for women to be hired by ‘organi- zations which require the constant display of friendliness … on the assumption that women are better at displays of warmth’ (mirchandani, : ) does not trans- late into adequate remuneration for the skills performed. an important feminist pro- ject has thus been to ‘expand the definition of skill to include emotional labour’ (steinberg and figart, : ) and to make visible the skills involved in perform- ing emotional labour effectively. it is to this project that we aim to contribute here. previous researchers have also identified emotional labour as a job require- ment for beauty therapists. gimlin ( ), for instance, asserts that ‘beauticians deal with their customers by attempting to create a personal relationship with them, listening to and remembering the intimate details of their lives, and claim- ing emotional attachment to them’ (p. ). similarly, sharma and black ( ) comment that beauty therapists are expected to give the client a ‘morale boosting “treat” … delivered in the context of attentiveness to that client’s indi- vidual needs and circumstances’ (p. ). black ( ) highlights the mismatch between job requirements and pay very clearly. she shows that emotional labour is needed in the salon to fulfil both short- and long-term organizational requirements. in the short-term, salons need ‘orderly and compliant’ clients, not clients ‘who will scream and thrash around as the pain of the electrolysis nee- dle kicks in, disturbing the woman in the next cubicle’ (sharma and black, : ). the long-term goal is to establish a loyal client base in a competi- tive market. both goals require skills beyond the practical ones taught at beauty college, yet even senior therapists are paid very poorly. black reports that the pay for uk beauty therapists actually decreased slightly from to : in the average hourly pay for a therapist was £ . , for a senior therapist £ . and for a salon manager £ . . in these respective figures stood at £ . , £ . , and £ . . nail technicians received £ . , a surprising figure, since this is actually below the legal minimum wage. ( : – ) women’s emotional labour in general, then, is a feminist issue; the poorly paid, highly gendered world of the beauty salon offers a particularly stark example. although concerned with actual workplace practices, much emotional labour research has relied on self-report data (frith and kitzinger, ). an alternative approach is to analyse what actually takes place in workplace inter- action. observational studies have gone some way towards doing this (e.g. korczynski, ; sanders, ). however, almost no emotional labour research has analysed recorded interactions (for an exception, see wingard, forthcoming, who uses conversation analysis to analyse instances of emotion work in video-recordings of families interacting at home). in the absence of such recordings, the researcher is reliant on summaries or idealizations of what occurred; the complex details of talk-in-interaction are irrecoverably lost. yet an analysis of these details is crucial, we argue, to the feminist project of mak- ing visible the skills involved in performing emotional labour. as part of a broader study of hair removal as paid work (see toerien and kitzinger, ), this article uses conversation analysis (ca) to examine emotional labour in emotional labour in action toerien & kitzinger by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com action. analysing a recorded instance of salon interaction, we ask: what does it take to do that which sociologists have theorized as emotional labour? part of the answer, we show, lies in employees’ capacity to be ‘multiply involved’ (lebaron and jones, ): to engage in more than one activity simul- taneously. how participants negotiate multiple involvements in a socially mean- ingful way has recently come under scrutiny within ca. goodwin and goodwin ( ), for example, address this complexity in a family’s mealtime activity. they show how the younger daughter negotiates competing claims for her alignment: by her sister, who is telling an extended story, and by her boyfriend who is seek- ing to get her ‘on side’ with his heckling of the story-teller. in addition, they show how the story-teller manages – through a gesture – the potential disruption of her story by an offer of more food. they deal also, then, with the coordination of talk and non-vocal interaction (see also stivers and sidnell, ). erickson ( ), similarly, analyses the coordination of turns at talk and eating during another family dinner. while multiple activities may be managed smoothly, such studies demonstrate that this is an accomplishment, requiring interactional skills; some- times, conflict between activities may have to be navigated. for example, lebaron and jones ( ), who analyse a chance reunion between two women at a hairdresser’s, show how it conflicts with the physical activity of hairdressing. in this article, we also focus on conflicting multiple involvements during a ser- vice encounter. we examine a single case that caught our attention precisely because it makes visible a moment of conflict between a beauty therapist’s engage- ment in the physical practices of shaping a client’s eyebrows and the relational practices of ‘chatting’ with the client. we begin by showing how the therapist nav- igates this conflict. we then ask what might be accomplished interactionally by her actions. it is a key argument of this article that both the ‘chat’, and the way the therapist navigates the conflict between ‘chat’ and hair removal, are empirical examples of what sociologists theorize as emotional labour. methodology and data we employ the tools of ca, which allow for a fine-grained analysis of recorded talk and non-vocal interaction. founded in the late s and early s by sacks et al. ( ; and see sacks, ), ca conceptualizes talk as a fundamental form of social action; as the means by which much of ‘the work of the constitutive institutions of societies gets done – institutions such as the economy, the polity, the family, socialization, etc.’ (schegloff, : ). from this perspective, ca is not just a method for studying talk; it is ‘a distinctive way of doing sociology’ (ten have, : ). ca’s basic goal is the ‘description and explication of the competences that ordinary speakers use … in participating in intelligible, socially organized interac- tion’ (heritage and atkinson, : ). classically, the focus has been on ‘ordinary’ interaction. however, there is now a substantial body of work concerned with institutional interaction, which involves at least one participant representing an insti- tution and an orientation to an institutionally defined set of tasks (drew and heritage, ). examples include counselling (silverman, ), calls for emergency assistance (whalen et al., ), presidential press conferences (clayman sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com and heritage, ), courtroom proceedings (drew, ), and doctor–patient con- sultations (heritage and maynard, ). in keeping with ca’s ethnomethodolog- ical origins, a key concern is with how participants themselves constitute the encounter and their social roles ‘as having some distinctively institutional character’ (drew and heritage, : ); with how ‘institutional realities are evoked, manip- ulated and even transformed in interaction’ (heritage, : ). there is not space here to review ca’s methods and findings. for excellent introductions to ca gener- ally, and the application of ca to institutional interaction, see heritage and atkinson ( ) and drew and heritage ( ), respectively. we used video and audio-tapes to record our data. as heath and hindmarsh ( ) emphasize, video-recordings are particularly important because they cap- ture the non-vocal actions that characterize most interaction. our data extract is taken from a salon session of about minutes long, recorded in february . the agreed goal is the removal of hair from the client’s eyebrows, legs, ‘bikini line’ and underarms. we transcribed all talk using jeffersonian transcription notation and include descriptions of key physical actions using curly brackets to show where these begin and end. stills from the video are shown as figures – , and the clip is available on the first author’s website: http://www.york.ac.uk/depts/soci/s_toer.htm provision of the clip is important so that readers do not have to rely on (unavoid- ably incomplete) transcription. however, this is only ethically acceptable where participants have given fully informed consent to the data being made widely available. in our study, participants – who were given detailed written and verbal information about our work – signed a consent form specifically allowing the data to be displayed. the beauty therapist requested that we include her and her salon’s name, which we are glad to in acknowledgement of her involvement. the extract (around one minute long) occurs min secs into the record- ing. the therapist is ‘threading’ the client’s right eyebrow; this is an ancient eastern technique, involving plucking the hairs with a loop of cotton. the client has experienced this procedure before with this therapist. in the extract, the therapist is standing at the top right-hand corner of a table, on which the client lies. the therapist holds a spool of thread in her right hand, with a loop of thread in her left and one end in her mouth (she is able to speak). the client’s eyes are closed throughout the procedure as protection against the light. (please note that the client’s name is a pseudonym.) cli i still find it hard to imagine how you actually do it? ( . ) bth do [you: :. real]ly. cli [ °hem hm°] ( . ) cli >i think it m[ust< take yea : : rs and year] bth [v e r y popular darli :ng,] cli ↑yea: : [ : h] bth [very] very popular. because: u : : : m ( . ) i g e t p e o p l e t r a v e l f r o m f a r f a r emotional labour in action toerien & kitzinger by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com away. cli do you teach people¿ bth .hhh i do: : : . if they want to. that’s what other thing i’m thinking of.=like teaching you kno: {w, = {bth stops threading cli = { ‘ c a u s e i k n o w l i k e i n a l l t h e {bth’s r hand held briefly alongside r side of cli’s face magaz { i n e s n o w t h e [ y ’ r e ] {bth extends r index finger bth [ y ]eah cli { they’ re saying you know [threading’s] {bth runs r index finger twice along cli’s r eyebrow bth [threading] cli d e f i n i t e l y t h e b e s t { w a : [ y , {bth runs r index finger along cli’s r eyebrow bth {[ b e s t w a y . t h a t ’ s t r u e : : . { st extension of bth’s r hand cli but i mean so {few {people know how to do it, { st retraction of bth’s r hand { nd extension of bth’s r hand {bth’s gaze shifts cli { [s o ] { nd retraction of bth’s r hand bth [that]’s {true{[: . {bth’s gaze shifts { rd extension of bth’s r hand [you could prob’ly do very { w e l l w i t h t e a c h i n [ g . ] {bth’s r hand extends towards cli’s r shoulder bth [mm] hm bth {suza: :nne? {bth’s gaze shifts {bth turns right hand so facing palm-down over cli’s body cli yea: [ : h? bth [with {this one darling, {bth touches cli’s r shoulder cli mhm, (.) bth pull your eye:l[id, (( lines omitted during which the therapist issues further directives, with which the client complies, and checks the client is okay)) { ( . ) {after about seconds, the bth begins threading bth °alright darlin’° ( secs) cli what i also like about the threading is it doesn’t take a l(h)ong ti(h)me. ((talk about threading continues)) sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com analytic section : navigating multiple involvements (i) simultaneous threading and topic talk our extract begins with the threading underway. the client initiates talk, topi- calizing the threading (lines – ), and the therapist responds, while maintain- ing a (predominantly) rhythmic series of plucks. although much could be said about this slice of interaction, our main point is that the therapist is engaged in both activities simultaneously; they are not in competition. (ii) interruption of threading; continuation of topic talk from lines – , the threading stops while the topic talk continues. during this time, the therapist’s hand movements are crucial to our analysis. we focus first on lines – . having stopped threading, the therapist’s right hand hov- ers momentarily along the right side of the client’s face (line ). she then extends her right index finger (line ) towards the client’s right shoulder. she also runs her finger twice along the client’s right eyebrow (lines & ), after which she retracts the finger, ending physical contact with the client’s face. these actions are not visible to the client, whose eyes are closed. however, to emotional labour in action toerien & kitzinger note: figures – printed with kind permission from mina rajdev (owner of chic beauty clinic, london) and client figure : first hand extension figure : first hand retraction figure : second hand extension figure : second hand retraction figure : third hand extension figure : shoulder-touch by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com an onlooker they contrast distinctively with the almost continuous threading action occurring prior to line – there is a sense of the threading being inter- rupted. while this may be only a ‘sense’ at this point, there follows some strong evidence that the therapist is deliberately delaying the threading with reference to the ongoing topic talk. this is made visible by the therapist’s hand move- ments over five seconds of the interaction, which we describe next. (iii) evidence of conflict:two aborted attempts to reinitiate threading jumping ahead to line , notice that the therapist uses touch as part of her directive to the client to pull her eyelid. the shoulder-touch displays to the client – whose eyes are closed – which hand the therapist means by ‘with this one’ (line ). the directive serves to elicit the client’s assistance, thereby reini- tiating the threading. in what follows, we show that the therapist makes two prior attempts to initiate this shoulder-touch, which she aborts in favour of the topic talk. the transcript and figures show where the therapist twice extends her hand towards the client’s shoulder only to retract it. we first describe where these hand movements occur before explicating their significance: • first aborted shoulder touch: as the therapist launches her agreement at line , she extends her right hand away from the client’s face, toward the client’s shoulder (figure ). a few words into the client’s next turn (line ), she retracts her hand (figure ). • second aborted shoulder touch: almost immediately after the first retrac- tion, the therapist extends her hand again (line ; figure ). she also glances away from the client’s face, along the right side of her body. towards the end of the client’s turn (line ; figure ), the therapist again retracts her hand. just before completing her responsive turn at line , the therapist again glances along the right side of the client’s body. • successful shoulder touch: as the client produces another assessment (lines – ), the therapist again extends her right hand, this time as far as the client’s shoulder, with her palm facing inwards towards the client’s body (figure ). as the therapist produces her summons to the client (line ), she turns her hand so that the palm is facing down over the client’s shoul- der. again, she glances down the right side of the client’s body. as she begins to issue her first directive to the client, she touches the client’s shoul- der (line , figure ). the therapist’s hand extensions are unavailable to the client, whose eyes are closed. they should not, then, be understood as recipient-designed gestures, which the client deliberately ignores or accidentally misses. rather, what makes them analytically interesting is that they make visible to us the therapist’s inten- tion to elicit the client’s assistance some time before she does so. in what fol- lows, we examine the relationship between the therapist’s hand movements and the talk in order to unpack this claim. sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com (iv) relationship between the hand movements and topic talk when the therapist first extends her hand, she is producing an assessment (line ) that agrees with the prior turn and adds nothing substantive. no further talk is conditionally relevant. when beginning her first hand extension, the therapist could, then, project topic closure and hence an upcoming place at which to initiate task-directed talk non-interruptively. however, the client con- tinues talking. the therapist’s retraction of her hand, which occurs partway through the client’s turn, may be understood as responsive to the resumed talk; as an abortion of the incipient shoulder-touch to avoid interrupting the client by initiating a directive sequence. the second retraction of the therapist’s hand, likewise, appears finely tuned to the ongoing talk: the hand is retracted as the client says ‘so’ (line ), by which point it is apparent that her turn offers an assessment, making relevant a second assessment from the therapist (pomerantz, ). thus, the therapist’s retracted hand may be understood to display an analysis of the client’s turn as making relevant a response, which she produces (line ) instead of initiating task-directed talk. the shift in the therapist’s gaze (line ) provides further evi- dence that this retraction is an aborted version of the shoulder-touch. not only does the therapist glance in the direction of the shoulder, but this gaze shift occurs again (line ) just before the onset of the final hand extension and dur- ing the summons (line ), suggesting that the gaze on all three occasions is directed at the goal of the incipient touch (the shoulder). the onset of the third extension of the therapist’s hand occurs, almost exactly like the first, as the therapist is coming to the end of a topic closing implicative turn: an agreement with a prior assessment (line ). again, therapist and client are aligned and the therapist has added nothing new. again, they could be done – a good place for the therapist to shift the talk back to the task, non- interruptively. again, however, the client resumes the topic talk (lines – ). this time, the therapist does not abort the hand extension. instead, she deals with the conflict between the topic talk and her attempt to elicit the client’s assistance in a different way: she closely coordinates the extension of her hand with the talk, extending it but not touching the client’s shoulder until she has the floor. notice how she gains the floor: not only does she produce a minimal agreement (line ) as soon as the client’s turn could be possibly complete, but she then issues a sum- mons (line ). the summons produces a clear shift between the prior talk and what is to come next, requesting the client to focus her attention on something new. moreover, it makes relevant something different to topic talk: a response to the summons (schegloff, ). the client responds (line ), giving the therapist the go-ahead. she now has the right to produce her directive – and complete her shoulder-touch – and does so, beginning at line . one feature of the hand movements, which supports our analysis of the first two as aborted attempts at the shoulder-touch, is their ‘progressivity’. by this we mean that each extension gets physically closer to the shoulder (com- pare figures , and , which show the maximum extension for each prior to emotional labour in action toerien & kitzinger by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com the actual touch) and each retraction takes the hand less far away (compare figures and , which show the maximum retraction for each). similarly, each of the therapist’s responsive turns is more minimal, adding less to the talk. the therapist is not mandated to abort the shoulder-touch by the client’s talk or the relevance of a responsive turn; this is a choice from alternatives (e.g. initiating her directive interruptively). she is actively managing the physical tasks of threading in relation to the task-irrelevant topic talk. she navigates the conflict between these multiple involvements by delaying the threading in favour of the topic talk. notice that from line the topic talk, reinitiated by the client, is resumed in tandem with the threading. in sum, the beauty therapist’s work includes managing the dual demands of topic talk and depilation; this requires, at times, navigating conflict between them. analytic section : emotional labour in action we now consider the interactional significance of the therapist’s actions. linking our microanalysis with the sociological concept of emotional labour, we argue that our extract provides evidence of two ways that a beauty therapist may per- form emotional labour: (i) by being ‘multiply involved’ and (ii) by navigating between her involvements in a way that maintains a ‘smooth’ interaction. (i) engaging in topic talk:treating the client as an individual as we have shown, the therapist engages in topic talk while performing the threading. at first glance we might dismiss this ‘chat’ as an example of emo- tional labour. it is not of an overtly emotional nature and is probably not what beauty therapists mean when they report a relational aspect to their work. sharma and black ( ) found that beauty therapists reported taking on a counsellor-like role when, for example, ‘clients confide about their family or marital problems in the course of a “treatment”’ (p. ). we suggest, however, that the relational side of salon work is far more pervasive than such instances imply. emotional labour includes, crucially, the successful personalizing of an encounter that is utterly routine for the therapist. as sharma and black put it: ‘at all costs the client must not feel that she is on a “production line” served by a robot’ (p. ). in our extract we see evidence of a practice for personalizing the session: engaging in topic talk while performing the depilation. this talk serves to build a relationship between client and therapist and demands that the therapist be responsive to the client ‘without resort to formulaic or standard- ized (“regimental”) responses’ (sharma and black, : ). the therapist’s ability to be ‘multiply involved’ – to perform the threading while simultane- ously ‘chatting’ with the client – is one of the many competences that enable her to treat the client as an individual. it should be understood, then, as an exam- ple of emotional labour in action. sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com (ii) navigating between multiple involvements: ‘smoothing’ the interaction we have also shown how, when navigating conflict between her multiple involvements, the therapist delays the hair removal. she gives precedence, not to the physical tasks for which she is officially paid, but to the relational tasks of not coming off as rude, overly hurried, or not listening properly. in the extract we see something of what it takes to ‘smooth’ an interaction, to prevent interactional ‘frictions’ (calhoun, : ), to ‘be polite’ (fineman, : ): the therapist must not only know how to be appropriately ‘multiply involved’ but also how to navigate smoothly between her involvements. she must perform the interactionally complex task of reorienting the client’s atten- tion to the job at hand, without interrupting the topic talk, which the client repeatedly sustains. if managed seamlessly, this navigation between multiple involvements may be invisible. that is the point: to ‘smooth’ an interaction suc- cessfully, the process cannot appear effortful. the extract is a clear example of this aspect of emotional labour not because the therapist gets it just right: rather, it is informative because the therapist’s hand extensions make visible to us her efforts to avoid generating interactional ‘friction’. while the moment of conflict is kept below the surface of the interaction – as it must be if the thera- pist is to come off as attentive and polite – her hand extensions allow us to glimpse the underlying mechanics of so doing. the interactional competences we analyse here are not ‘spectacular’ in the way that dealing with an enraged or grieving client might be. they are, how- ever, the sorts of mundane (i.e. everyday, taken-for-granted) relational skills we expect from our service providers. they are the sorts of skills that, if practised well, leave us feeling ‘looked after’, and if not, leave us thinking we may go else- where in future. discussion and conclusions hochschild’s ( ) coining of the terms ‘emotional labour’ and ‘emotion work’ has generated a multi-faceted body of research. almost none of it, how- ever, has examined recordings of naturally occurring interaction to understand what emotional labour/emotion work might look like in practice. as wingard (forthcoming) argues: without actually viewing interactions in which emotion work occurs, researchers can- not tap into how emotion work is interactionally accomplished, what kinds of conse- quences it has for participants in that interaction, or even register an actual range of the different kinds of emotion work that might exist in particular interactions. showing how wide a ‘variety of disparate kinds of interactions and strategies’ have been termed emotional labour/emotion work, wingard proposes that ‘an initial typology of the kinds of verbal and nonverbal strategies that are instrumental in performing emotion work’ would be useful. the present article emotional labour in action toerien & kitzinger by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com contributes to this fledgling project by explicating a recorded empirical example of emotional labour in the beauty salon. focusing on a moment of conflict between a beauty therapist’s simultaneous involvement in depilation and ‘chat’, we have demonstrated two kinds of strategy for performing emotional labour: (i) being ‘multiply involved’ and (ii) navigating appropriately between these involve- ments. in this case, the therapist’s delay of the hair removal in favour of the ‘chat’ gives precedence to her relational tasks; it is in this sense that her navigation of her involvements may be understood as an example of emotional labour. the idea that beauty therapy entails emotional labour is not new; neither is the political point that emotional labour is poorly recognized and rewarded. yet the tendency to rely on interview or observational data has rendered researchers unable to demonstrate, in action, the interactional skills required to perform emotional labour. this is ironic given the feminist commitment to making women’s skills visible. tancred ( ), for instance, argues that emo- tional labour is an excellent example of work involving invisible skills and con- cludes that feminist analysis is crucial to help extend the definition of skill. interestingly, in light of our analysis, she suggests that, ‘if women’s work were to be taken as the norm, the ability to deal with several tasks simultaneously might well head the list in evaluating the difficulty of the job’ (p. ). however, without a video recording, it is hard to imagine having recognized the signifi- cance of the beauty therapist’s hand movements with respect to her manage- ment of simultaneous tasks. more generally, while beauty therapists would likely recognize the importance of ‘chat’ for making the client feel good, they could not be expected to articulate the interactional skills required to navigate between ‘chat’ and depilation. conversation analysis, with its tools for expli- cating how participants do interaction, offers an ideal method for making rela- tional skills visible. our key contribution to the emotional labour literature, then, stems from our application of ca to the study of beauty therapy. with respect to ca, our main contribution is to the understanding of how participants manage their multiple involvements. in this respect, our analysis is closely aligned with research by lebaron and jones ( ), who also address a moment of conflict between topic talk and work on a client’s body (her hair). however, while they analyse conflict generated by an additional interaction, we show how multiple involvements may conflict within dyadic talk. moreover, the nature of the conflicts is different. in the former, it is overt and enacted between hairdresser and client. the hairdresser resists the client’s attempts to interrupt the hairdressing: jane [the hairdresser] repeatedly turns katie’s body … and even sprays katie’s face … to preserve the spatial integrity of the hairdressing activity. thus, katie must work to initiate a reunion, which is bodily at odds with other involvements. (lebaron and jones, : – ) by contrast, the conflict in our extract is never allowed to rise to the surface of the interaction, and remains a conflict – for the therapist alone – between com- peting activities. like katie, she needs to close down one activity in favour of sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com another. to do this she must accomplish a mundane interactional task: eliciting the client’s attention. what makes our extract unusual is that the client’s eyes are closed. the therapist cannot, then, make use of the non-vocal attention-getting devices (e.g. body movements) that heath ( ) has shown speakers using to encourage a display of recipiency. the therapist’s hand movements are not recipient designed. rather, they are technically interesting because they afford a glimpse of the mechanics of how the therapist manages her multiple involvements. obtaining the client’s attention is of interactional delicacy because – unaware of the therapist’s intentions – she repeatedly reinvigorates the topic talk. non- vocal attention-getting devices deal with such delicacy by allowing ‘the partici- pants to maintain involvement in the business at hand, without having to address the problem of involvement as a topic in its own right’ (heath, : ). unable to subtly get the client on side, the therapist’s difficulty is how to obtain her attention non-interruptively. ultimately she uses a vocal summons. however, as we have shown, this is delayed precisely in order to deal with the interactional delicacy. our analysis points to some of the difficulties of manag- ing multiple involvements when participants have differential access to non- vocal actions. further similar research has the potential to produce findings of practical applicability (e.g. for interactions between sighted and blind partici- pants). an important implication of our work for conversation analysts is that topic talk should not be assumed to be independent of the ‘official business’ of the institution. like mchoul and rapley ( ), who analyse ‘chat’ on a com- puter helpline, we would argue that: while the term ‘chat’ may, conventionally, gloss some kind of disengagement from businesslike conversation, while it may seem to be ‘small talk’, of no weight, irrele- vant even, it might rather be (as inspection of some actual materials shows) that it’s in fact ultra-critical to keeping the ‘serious’ stuff happening. (bite , bit ) like mchoul and rapley’s analysis, ours problematizes any neat distinction between ‘talk at work’ and ‘talk as work’: while topic talk is clearly superflu- ous to removing hair (and, as such, may be said to be ‘talk at work’), it is also a form of ‘talk as work’ – emotional labour. taken as a whole, then, this arti- cle has addressed both the feminist issue of emotional labour and the conver- sation analytic concern with how participants manage multiple involvements in a socially meaningful way. offering a single-case analysis, this article is exploratory, providing sign- posts for future work, rather than a comprehensive explication of emotional labour practices. it is more common for conversation analysts to work with a collection of data fragments. however, arguing that the single-case analysis is ‘a central office for sociology, one which has not received the same attention as other of its jobs’ (p. ), schegloff ( ) points out that: social action done through talk is organized and orderly not, or not only, as a mat- ter of rule or as a statistical regularity, but on a case by case, action by action, basis emotional labour in action toerien & kitzinger by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com … accordingly, an analytic machinery which is meant to come to terms with the orderliness of interaction … should be able to deal in an illuminating manner with single episodes of talk taken from ‘the real world’ … whatever concerns for macrosocial issues we entertain, our ways of dealing with them will in the end have to be compatible with a capacity to address the details of single episodes of action through talking in interaction. (p. ) going on to suggest that ‘much grander themes can often be … clearly seen’ ( : ) in single instances of real-life social action, schegloff uses a single- case analysis to examine conflict; we have done the same for emotional labour. in doing so within a feminist agenda, this article joins a growing feminist conversation analytic project, which brings the tools of ca to bear on substan- tive feminist concerns (see kitzinger, ; speer, ; stokoe and weatherall, ). recent examples include research on coming out as lesbian (land and kitzinger, ), the construction of hiv/aids in lesbian and gay awareness training (kitzinger and peel, ), calls to a home-birth helpline (shaw and kitzinger, ), and how psychiatrists and clients in uk gender identity clinics jointly construct the client’s passing as a woman (speer and green, ). such work seeks to remain true to the ca principle that analytic claims must be grounded in participants’ practices. at the same time, the aim is to go beyond the ‘basic science’ of how interaction works, using ca to say something of political relevance. in blending these aims, feminist ca should offer something to feminists and conversation analysts. here we have drawn out the implications of our analysis for each audience. seeking to understand both the mechanics of social action and the socio-political consequences thereof is, in our view, a hallmark of an adequate feminist ca. within the highly gen- dered, low-paid world of beauty therapy, using our technical analysis to argue for the recognition of emotional labour as skilled is significant. while the skills we demonstrate are hardly ‘spectacular’, that does not dimin- ish their importance. on the contrary, we would argue that their ‘everydayness’ is what makes them crucial: they are not merely required under special circum- stances (e.g. dealing with an upset client), but are fundamental to the routine work of beauty therapy. ironically, it is their ‘everydayness’ that makes these skills so difficult to recognize. woven into the fabric of everyday interaction, they are even subtler – and hence more hidden – than the critical literature has suggested. acknowledgements special thanks to our participants for allowing us to record and publish their interac- tion. we are grateful to tony wootton for inspiring and commenting on this analysis, to sue wilkinson for co-supervising merran’s doctoral research and for feedback on an earlier draft, and to the editors, anonymous referees and sue speer for helpful sugges- tions. this research was started at loughborough university and completed at the university of york, with funding from the emma smith overseas scholarship (university of kwa-zulu natal, south africa) and the sir richard stapley educational trust (uk). thanks to the mrc hsrc for affording merran time to write this article. sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com notes key to jeffersonian transcription [ ] square brackets indicate the points at which overlapping talk begins and ends. = equal signs indicate no gap between lines/turns. ( . ) numbers in parentheses indicate silent intervals within or between talk measured in tenths of a second. (.) dot in parentheses indicates a silence too short to measure in tenths of a second. . full stop indicates closing intonation. , comma indicates slightly upward ‘continuing’ intonation. ? question mark indicates rising intonation. ¿ inverted question mark indicates rising intonation weaker than that indicated by a question mark. : colon indicates extension of preceding sound – the more colons the greater the extension. ↑↑↓↓ up or down arrow indicates marked rise or fall in intonation. here underlining indicates emphasized talk. here upper case indicates louder talk. °here° degree signs indicate softer talk. >this< greater than and less than signs indicate speeded up talk. (h) ‘h’ in brackets indicates audible aspirations in speech (e.g. laughter particles). we are not claiming that the participants themselves are oriented to the per- formance of ‘emotional labour’ in the episode under analysis. our goal, here, is not to examine ‘emotional labour’ as a members’ term. nevertheless, we remain focused on members’ own practices as we seek to demonstrate some of the interactional skills involved in performing that which sociologists have dubbed ‘emotional labour’. the relationship between analysts’ and partici- pants’ categories is a contested issue across conversation analysis, discourse analysis, discursive psychology and membership categorization analysis, but unfortunately we do not have space to pursue that discussion here. what makes this analysis an example of feminist ca is, in our view, the fact that we have employed the tools of ca to meet a feminist end: arguing for the recognition of invisible skills for which women are seldom remunerated. our understanding of beauty therapy and emotional labour as gendered is based, then, on the prior literature; our focus here has not been on gender as a cate- gory in our data. a fascinating extension of our work would be to examine how gender is invoked, displayed and oriented to during the hair removal ses- sions. unfortunately, this is beyond the scope of this article. we are grateful to an anonymous referee for highlighting this point. references black, p. 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(forthcoming) ‘an interactional analysis of emotion work in naturally occurring family interaction’. merran toerien is the rcuk fellow in communication and language use in interaction in the department of sociology at the university of york. her current research centres on ca as applied to institutional talk-in-interaction, including encounters between patients and health professionals, and employment advisers and clients. she has published pre- viously on feminism, gender and the body in feminism & psychology, qualitative research in psychology, sex roles and women’s studies international forum. address: department of sociology,the university of york, heslington,york yo dd, uk. e-mail: mgt @york.ac.uk celia kitzinger is professor of conversation analysis, gender and sexuality in the department of sociology at the university of york. she has published nine books and around arti- cles and book chapters on issues related to language, genders and sexualities. she is cur- rently working with a corpus of calls to a helpline from women in trauma after childbirth. address: department of sociology, university of york, heslington,york yo dd, uk. e-mail: cck @york.ac.uk sociology volume ■ number ■ august by sandra hopps on october , http://soc.sagepub.comdownloaded from http://soc.sagepub.com discipline of elementary school students. procedia social and behavioral sciences. , – paisal, k. . learning activities that promote ability the proof groups using the internet network. procedia - social and behavioral sciences . , – riduwan. . skala pengukuran variabel- variabel penelitian. bandung: cv. alfabeta sugiyono. . metode penelitian pendidikan. bandung: alfabeta sundayana. . statistika penelitian pendidikan. bandung : alfabeta suryanto, a. & kusumawati, d. a. . developing a virtual reality application of the lawang sewu building as educational media for the subject of history. jurnal pendidikan teknologi dan kejuruan. . , - vermunt, j. d., & verloop, n. . congruence and friction between learning and teaching. learning and instruction. , – relevance of the productive course of hair beauty in vocational high schools to industry needs ambiyar , asmar yulastri , mimi yupelmi , paryono , , study program of technological and vocational education, universitas negeri padang, indonesia seameo regional centre for vocational and technical education, brunei darussalam e-mail: ambiyar@ft.unp.ac.id abstract the problem primarily faced by vocational education institutions is a gap between skills taught at schools and skills required by the industries. this leads to the increasing unemployment rate of vocational high school graduates. thus relevant curriculum is required to satisfy the industry demands. this study aimed at analyzing the relevance of the productive course of hair beauty in vocational high schools to the job requirements in beauty salons in padang. this study was qualitative descriptive. the data collection used interviews, observation and documentation. the data collection instruments consisted of observation sheets and interview guidelines. the data were analyzed using the stages of data reduction, presentation and conclusion. the results showed positive relevance of the productive course of hair beauty in vocational high schools to the job requirements in beauty salons in padang. the skills learned in the schools were adequately relevant with the skills required by beauty salons, since from thirteen productive lessons taught in the schools, eleven of them were implemented and used in the workplaces. keywords: hair beauty, industry needs, productive course, relevance introduction the challenges of globalization era demand people to be ready and to give quick response to improve human resources. hendayat ( ) states that human resources generated by the world of education will be the resource that underpins implementation of industrialization in indonesia, therefore the policies of human resources development must be started with the improvement of the education system that leads to the provision of human resources used in industries. subsequently, education has the important role to provide high-quality human resources. education in schools requires a curriculum. a curriculum that used by vocational high schools also known as sekolah menengah kejuruan (smk) should be relevant with the existing needs in the business world and industrial world, because the curriculum is an important thing in the education and significantly affect the quality of the graduates. mulyasa ( ) suggests that every educational unit is expected to develop a curriculum that can be implemented in each educational unit. sumantri ( ) also states that curriculum must be started with the specification of students’ needs, because the target of the curriculum is designed based on community’s needs, because the community will be the users of the graduates. in addition, mangkunegaran ( ) explains that education is considered relevant if the results obtained from education are useful for real life. the education which is not relevant with the demands of the world of work will produce the graduates who are hardly able to face the demands of the world of work. in relation to the relevance of education, relevance is defined as relationship, conformity, connection of the objectives, useful directly with what is needed. djojonegoro ( ) states that the policy to increase quality and relevance of education, includes four aspects namely curriculums, educational staffs, educational facilities and leadership of educational units. sadjad ( ) adds that relevance is an important component because relevance is the factor that determines the existence of an educational institution. the educational institutions can be considered jurnal pendidikan teknologi dan kejuruan, vol. , no. , may , pp. - issn: - , accredited by kemenristekdikti, decree no: /e/kpt/ doi: . /jptk.v i . received february , ; revised march , ; accepted march , jurnal pendidikan teknologi dan kejuruan,vol. , no. , may relevant if the graduates can be quickly absorbed by employment in accordance with the fields and the academic background, either in local, national, or international levels. so that, the curriculum relevance to the industrial world’s needs becomes important in order to produce qualified graduates to be employed by the industries. in relation with vocational education, wardiman ( ) states that vocational education is a part of an education system that prepares someone to work in the workgroup or a work field from the other work fields. therefore, the development of curriculum must be directed to prepare students to enter the employment as human resources who are ready to face the free market that demands quality improvement of competitive and productive human resources. this is a challenge for the educational world. several problems faced by educational institutions are incompatibility and a gap between skills competency that learned at vocational high school and the skills need by the world of industries (marleni, ). moreover, masriam ( ) suggests that the employers consider that various vocational education efforts are not relevant to their needs. the educational program carried out by vocational education tend to be educationally concept oriented, either in the content of the lessons or in the values contained in the lesson. learning in the vocational education tends to be efforts to only develop knowledge and theories and ignore the performance which is the key to reach the characteristic of a competency. the effect of this gap is the low employment rate of vocational high school graduates by the industries. in august , the central bureau of statistics states that the open unemployment rate is still dominated by senior high school or vocational high school graduates that reaches . % which is improved from . % in february . the deputy of social statistics of the central bureau of statistics states that two out of five vocational high school graduates are categorized as unemployed (anaf, ). similarly, from all of graduates of smk n padang and smk n padang from to , the percentages of unemployed graduates are . % and . % respectively (public relations of smkn padang and smkn padang). the unemployment is caused by the students who lack skills in working. the evaluation results of vocational education and training, indicate that vocational education and training both in content and in the process does not cover the area of competence optimally (masriam, ). vocational education hardly capture the essence of a job or is unable to properly integrate the learning process with employment demands. materials presented to students and their relevance to the needs of the world of work tend to be very rarely concerned. to improve vocational education, this problem must be settled. observations and interviews with teachers of beauty therapy at smk n padang revealed that based on the spectrum of on the division of subjects to be taught in one semester, there are some subjects that are almost same with the other subjects with too much time allocation, resulting in low competency achievement of the graduates. for example, the subject of hair straightening, in which the lesson of hair straightening and smoothing is separately taught in class xi in hours a week for each subject and in the same semester in class xii the students also study hair straightening in hours a week. another problem in smk negeri padang is the subject of hair wash and hair drying which is also separated by the time allocation of hours a week for each subject. these subject should be combined to save time. the remaining time can be used to teach students about the service needed by the community and the industries today such as makeup and mahendi art to increase knowledge and skills of the students according to the needs of the world of work. some complaints from the beauty salon industries such as meihua salon and andri salon which state there are still many graduates who do not know the equipment used in the hair arrangement, lack of psychomotor competence such as hair pruning and coloring. they only know the theory only. interviews on martha siska salon, lian salon and roni salon shows that there are graduates who are still hesitant in carrying out the activity of hair straightening and do not understand and master services in beauty salons like hair blow, hair curling. the graduates also do not know other services in beauty salons such as mahendi and electric facials. referring to the problems that have been described before, it is necessary to express the relevance of the curriculum applied in schools with the job requirements in beauty salons. therefore, this study examines the relevance of vocational high schools curriculum to the job requirements of beauty salons in padang. method this study used a qualitative descriptive method. the reason for using the qualitative approach in this study was because the researcher saw the characteristics of the problem that could develop naturally in line with condition and situation of the field. sudjana ( ) stated that descriptive studies take the problem or the focus on actual problems as it is at the time of the study is carried out. to show the relevance of curriculum to beauty salons’ requirements, it was carried out a job analysis in addition to documentation and observation. the locations of study were smk n and smk n padang. the study was also carried out at six beauty salons where the graduates of smk n and smk n padang that consisted of meihua salon & bridal, martha siska salon, andri salon, roni salon, edri salon, and lian salon. data collection techniques were observations, interviews and documentation. in this study, the researcher played the role of a passive participant. moleong ( ) stated that participant observation technique is the main technique in qualitative studies. the interview was carried out with beauty salon staffs, teachers, graduates who had worked in the beauty salons in padang. there were six, four and six research informants form industrial staffs or beauty salons, from teachers and from the graduates respectively. the four teachers consisted of two teachers form smk n and two teachers from of smk n padang. there were six research informants form graduates. the interview consisted of , and questions for beauty salon staffs, teachers, and the graduates respectively. the data was also obtained through observation about the learning process and the performance of the graduates in their workplaces. skills were observed in this observation including ( ) hair washing, ( ) hair drying, ( ) hair and scalp care, ( ) hair cutting, ( ) hairstyling, ( ) hair curling, ( ) hairpiece styling, ( ) hairstyling, ( ) hair bun, ( ) traditional hair bun, ( ) barber techniques, ( ) hair dyeing, and ( ) hair straightening. the data was obtained from the curriculum documentation analysis and syllabus. a technique to check for validity data is triangulation activity toward the source that means to compare and check the degree of believing of information that obtained with other informant and triangulation with theory. data collected with various technique, and then carried out analysis data. there are steps in qualitative research, are follows: data reduction, presentation of data and draw a conclusion (moleong, ; sugiyono, ; miles & huberman, ). results and discussion the skills learned by students at the school correspond with the syllabus in the curriculum of hair beauty. there are skills taught through theoretical and practical studies. the students are expected to be careful and not in a hurry in the practices to keep occupational safety and to be responsible for the practice the productive course of hair beauty learned in the school is a vocational basic relevant if the graduates can be quickly absorbed by employment in accordance with the fields and the academic background, either in local, national, or international levels. so that, the curriculum relevance to the industrial world’s needs becomes important in order to produce qualified graduates to be employed by the industries. in relation with vocational education, wardiman ( ) states that vocational education is a part of an education system that prepares someone to work in the workgroup or a work field from the other work fields. therefore, the development of curriculum must be directed to prepare students to enter the employment as human resources who are ready to face the free market that demands quality improvement of competitive and productive human resources. this is a challenge for the educational world. several problems faced by educational institutions are incompatibility and a gap between skills competency that learned at vocational high school and the skills need by the world of industries (marleni, ). moreover, masriam ( ) suggests that the employers consider that various vocational education efforts are not relevant to their needs. the educational program carried out by vocational education tend to be educationally concept oriented, either in the content of the lessons or in the values contained in the lesson. learning in the vocational education tends to be efforts to only develop knowledge and theories and ignore the performance which is the key to reach the characteristic of a competency. the effect of this gap is the low employment rate of vocational high school graduates by the industries. in august , the central bureau of statistics states that the open unemployment rate is still dominated by senior high school or vocational high school graduates that reaches . % which is improved from . % in february . the deputy of social statistics of the central bureau of statistics states that two out of five vocational high school graduates are categorized as unemployed (anaf, ). similarly, from all of graduates of smk n padang and smk n padang from to , the percentages of unemployed graduates are . % and . % respectively (public relations of smkn padang and smkn padang). the unemployment is caused by the students who lack skills in working. the evaluation results of vocational education and training, indicate that vocational education and training both in content and in the process does not cover the area of competence optimally (masriam, ). vocational education hardly capture the essence of a job or is unable to properly integrate the learning process with employment demands. materials presented to students and their relevance to the needs of the world of work tend to be very rarely concerned. to improve vocational education, this problem must be settled. observations and interviews with teachers of beauty therapy at smk n padang revealed that based on the spectrum of on the division of subjects to be taught in one semester, there are some subjects that are almost same with the other subjects with too much time allocation, resulting in low competency achievement of the graduates. for example, the subject of hair straightening, in which the lesson of hair straightening and smoothing is separately taught in class xi in hours a week for each subject and in the same semester in class xii the students also study hair straightening in hours a week. another problem in smk negeri padang is the subject of hair wash and hair drying which is also separated by the time allocation of hours a week for each subject. these subject should be combined to save time. the remaining time can be used to teach students about the service needed by the community and the industries today such as makeup and mahendi art to increase knowledge and skills of the students according to the needs of the world of work. some complaints from the beauty salon industries such as meihua salon and andri salon which state there are still many graduates who do not know the equipment used in the hair arrangement, lack of psychomotor competence such as hair pruning and coloring. they only know the theory only. interviews on martha siska salon, lian salon and roni salon shows that there are graduates who are still hesitant in carrying out the activity of hair straightening and do not understand and master services in beauty salons like hair blow, hair curling. the graduates also do not know other services in beauty salons such as mahendi and electric facials. referring to the problems that have been described before, it is necessary to express the relevance of the curriculum applied in schools with the job requirements in beauty salons. therefore, this study examines the relevance of vocational high schools curriculum to the job requirements of beauty salons in padang. method this study used a qualitative descriptive method. the reason for using the qualitative approach in this study was because the researcher saw the characteristics of the problem that could develop naturally in line with condition and situation of the field. sudjana ( ) stated that descriptive studies take the problem or the focus on actual problems as it is at the time of the study is carried out. to show the relevance of curriculum to beauty salons’ requirements, it was carried out a job analysis in addition to documentation and observation. the locations of study were smk n and smk n padang. the study was also carried out at six beauty salons where the graduates of smk n and smk n padang that consisted of meihua salon & bridal, martha siska salon, andri salon, roni salon, edri salon, and lian salon. data collection techniques were observations, interviews and documentation. in this study, the researcher played the role of a passive participant. moleong ( ) stated that participant observation technique is the main technique in qualitative studies. the interview was carried out with beauty salon staffs, teachers, graduates who had worked in the beauty salons in padang. there were six, four and six research informants form industrial staffs or beauty salons, from teachers and from the graduates respectively. the four teachers consisted of two teachers form smk n and two teachers from of smk n padang. there were six research informants form graduates. the interview consisted of , and questions for beauty salon staffs, teachers, and the graduates respectively. the data was also obtained through observation about the learning process and the performance of the graduates in their workplaces. skills were observed in this observation including ( ) hair washing, ( ) hair drying, ( ) hair and scalp care, ( ) hair cutting, ( ) hairstyling, ( ) hair curling, ( ) hairpiece styling, ( ) hairstyling, ( ) hair bun, ( ) traditional hair bun, ( ) barber techniques, ( ) hair dyeing, and ( ) hair straightening. the data was obtained from the curriculum documentation analysis and syllabus. a technique to check for validity data is triangulation activity toward the source that means to compare and check the degree of believing of information that obtained with other informant and triangulation with theory. data collected with various technique, and then carried out analysis data. there are steps in qualitative research, are follows: data reduction, presentation of data and draw a conclusion (moleong, ; sugiyono, ; miles & huberman, ). results and discussion the skills learned by students at the school correspond with the syllabus in the curriculum of hair beauty. there are skills taught through theoretical and practical studies. the students are expected to be careful and not in a hurry in the practices to keep occupational safety and to be responsible for the practice the productive course of hair beauty learned in the school is a vocational basic ambiyar et al., relevance of the productive course of hair beauty in vocational high schools to industry needs jurnal pendidikan teknologi dan kejuruan,vol. , no. , may productive program including ( ) services, ( ) anatomy and physiology, ( ) cosmetics, ( ) spa services, and ( ) occupational health and safety (osh). the basic competencies of the course are as follows: ( ) hair washing, ( ) hair drying, ( ) hair and scalp care, ( ) hair cutting, ( ) hairstyling, ( ) hair curling, ( ) hairpiece styling, ( ) hairstyling, ( ) hair bun, ( ) traditional hair bun, ( ) barber techniques, ( ) hair dyeing, and ( ) hair straightening. the problem aroused is that the students lack of confidence in doing certain hair cutting and barber techniques because they have high risks. the schools also do not provide the students with adequate practical equipment that correspond to the development of the industry thus the students are not ready when going to the workplaces. moreover, the other problem is that some skills are not really used in the workplaces such as traditional bun and hair pieces. these skills are usually only used by beauty salons that provide special makeup and for weddings. the skills are not used in regular beauty salons because the consumers usually go for body care. to carry out effective and efficient works in the industry, the students or graduates should be equipped with competencies. competencies derived from the word of competency which is an adjective that means competence, ability, and authority. the adjective of competence is competent that mean competence, can, and agile. robbin ( ) defines a competency as the ability to carry out a certain job determined by intellectual and physical abilities. a competency includes ( ) how to do a job, ( ) how to organize the job, so the job can be accomplished, ( ) what should be done if the other things happen that are different with preliminary planning, and ( ) how to use the competency to solve the problem or to do the job with different condition. all of these are human characteristic as learning outcomes in the education field. a competency taught in the school have corresponded with the syllabus in the curriculum of hair beauty, although there are still some skills that have been not mastered by students like hair cutting and barber techniques. this happens because of the students’ lack of confidence in cutting practices. to increase the students’ ability, the students must train and improve their confidence so that they can practice any work. all of the graduates who enter the workplaces have basic skills to work at a beauty salon, although it still cannot be considered as a professional. there are still many graduates who lack the skills of hair cutting, barber techniques, and styling. to increase the students’ ability, it should be started with the students’ confidence so that students can do what they must do, and the school should focus more on practical learning than theories. the competency of the graduates must correspond with the beauty salons’ job requirements and to the industry standard. the learning process has corresponded with the industry needs, but in the fact, it still found graduates who cannot comply the industry needs to show professional skills. anastasia ( ) explaines that beauty salon business is a business in the field of beauty services and body care to maintain and restore life vitality. melcalf & bijan ( ) adds that a beauty salon is a special place to care the body using beauty equipment and cosmetic materials that are carried out by beauty experts. indonesian ministry of health ( ) states that service activities in the science of beauty implemented in a beauty salon business can be grouped in four main parts as follows: (a) skin care, (b) makeup, (c) hair care and (d) haircut. furthermore, hakim ( ) states that applying beauty skills are associated with hair styling and caring, body caring, and makeup. generally, the skills learned by graduates in the school are relevant with the industry’s needs, although there are some skills that are less used like hairpiece, traditional bun, so that the skills cannot be applied at the salon, and there are services that must be learned by students in the school are hijab and mahendi art. the students’ competencies which are not relevant with the industry needs are presented in table . table . students’ competencies which are not relevant with the industry needs competencies problems industry needs traditional bun the industry provides them especially for makeup and wedding salons, costumers mostly wear hijab competency of hijab and mahendi art, because hijab and mahendi art are required by the constumers hairpiece barber techniques students still study basic and theoretical materials, it has a high risk, inadequate tools in the school students should understand about barber techniques l before going to industry the teachers of hair beauty at smk n padang and smk n padang state that the beauty salons and the graduates that work in the beauty salon say that generally, the skills that learned in the school are relevant with the skills required by beauty salons. of productive courses taught in the school, courses can be applied and used by the salon staffs. there are just skills that are not used by beauty salons, namely traditional bun and hair pieces. in addition, the graduates lack hair cutting skills which are required by the industry. graduates of vocational education are expected to work in an industrial world that corresponds with their skills. vocational education is education that aims to ( ) make ends meet of communities for the labor market, ( ) to increase education choice for each individual, and ( ) to grow motivation to learn throughout life. evans & edwin ( ) adds that vocational education is a part of an education system that prepares individuals for the job or job groups. vocational education is all of type and form of learning experiences that help students to carry out their vocational development steps from identification, exploration, orientation, preparation, choosing and making a career in the workforce. it can be said that vocational education is education to enter the workforce and for everyone that needs it. the limits of vocational education show that vocational education is identical with the education of the world of work. the new graduates can be said competent if they have reached competency standards that determined by the school and the indonesian national competency standards. perseverance and abilities that had by students become the factor in determining the learning mastery besides normative and adaptive values. assessments of attitude, knowledge, and skill are put together to see the students can continue to the next step or not. for incompetent students cannot continue to the next competency. to reach the students’ competency, they must do their work optimally with or without a teacher. after the students have the competency, the students can ask the teacher to assess them about their competency and declared to be competent by the teacher. corresponding with the regulation of the indonesian minister of health, the students pass the primary and secondary education after accomplishing all learning programs, get minimum values either in the last assessment for all group courses, religion course and good attitude, nationality and personality, aesthetics course group, physical course group, sports, and health, pass the school exam for science and technology and pass the national exam (ministry of health, ). it means a productive course of hair beauty is divided into two namely the productive program and hair vocational competency productive program. the basic vocational productive program consists of ( ) services, ( ) anatomy and physiology, ( ) cosmetics, ( ) spa services, and ( ) osh. the hair beauty competency productive program course consisted of ( ) hair washing, ( ) hair drying, ( ) hair and scalp care, ( ) hair cutting, ( ) hairstyling, ( ) hair curling, ( ) hairpiece styling, ( ) hairstyling, productive program including ( ) services, ( ) anatomy and physiology, ( ) cosmetics, ( ) spa services, and ( ) occupational health and safety (osh). the basic competencies of the course are as follows: ( ) hair washing, ( ) hair drying, ( ) hair and scalp care, ( ) hair cutting, ( ) hairstyling, ( ) hair curling, ( ) hairpiece styling, ( ) hairstyling, ( ) hair bun, ( ) traditional hair bun, ( ) barber techniques, ( ) hair dyeing, and ( ) hair straightening. the problem aroused is that the students lack of confidence in doing certain hair cutting and barber techniques because they have high risks. the schools also do not provide the students with adequate practical equipment that correspond to the development of the industry thus the students are not ready when going to the workplaces. moreover, the other problem is that some skills are not really used in the workplaces such as traditional bun and hair pieces. these skills are usually only used by beauty salons that provide special makeup and for weddings. the skills are not used in regular beauty salons because the consumers usually go for body care. to carry out effective and efficient works in the industry, the students or graduates should be equipped with competencies. competencies derived from the word of competency which is an adjective that means competence, ability, and authority. the adjective of competence is competent that mean competence, can, and agile. robbin ( ) defines a competency as the ability to carry out a certain job determined by intellectual and physical abilities. a competency includes ( ) how to do a job, ( ) how to organize the job, so the job can be accomplished, ( ) what should be done if the other things happen that are different with preliminary planning, and ( ) how to use the competency to solve the problem or to do the job with different condition. all of these are human characteristic as learning outcomes in the education field. a competency taught in the school have corresponded with the syllabus in the curriculum of hair beauty, although there are still some skills that have been not mastered by students like hair cutting and barber techniques. this happens because of the students’ lack of confidence in cutting practices. to increase the students’ ability, the students must train and improve their confidence so that they can practice any work. all of the graduates who enter the workplaces have basic skills to work at a beauty salon, although it still cannot be considered as a professional. there are still many graduates who lack the skills of hair cutting, barber techniques, and styling. to increase the students’ ability, it should be started with the students’ confidence so that students can do what they must do, and the school should focus more on practical learning than theories. the competency of the graduates must correspond with the beauty salons’ job requirements and to the industry standard. the learning process has corresponded with the industry needs, but in the fact, it still found graduates who cannot comply the industry needs to show professional skills. anastasia ( ) explaines that beauty salon business is a business in the field of beauty services and body care to maintain and restore life vitality. melcalf & bijan ( ) adds that a beauty salon is a special place to care the body using beauty equipment and cosmetic materials that are carried out by beauty experts. indonesian ministry of health ( ) states that service activities in the science of beauty implemented in a beauty salon business can be grouped in four main parts as follows: (a) skin care, (b) makeup, (c) hair care and (d) haircut. furthermore, hakim ( ) states that applying beauty skills are associated with hair styling and caring, body caring, and makeup. generally, the skills learned by graduates in the school are relevant with the industry’s needs, although there are some skills that are less used like hairpiece, traditional bun, so that the skills cannot be applied at the salon, and there are services that must be learned by students in the school are hijab and mahendi art. the students’ competencies which are not relevant with the industry needs are presented in table . table . students’ competencies which are not relevant with the industry needs competencies problems industry needs traditional bun the industry provides them especially for makeup and wedding salons, costumers mostly wear hijab competency of hijab and mahendi art, because hijab and mahendi art are required by the constumers hairpiece barber techniques students still study basic and theoretical materials, it has a high risk, inadequate tools in the school students should understand about barber techniques l before going to industry the teachers of hair beauty at smk n padang and smk n padang state that the beauty salons and the graduates that work in the beauty salon say that generally, the skills that learned in the school are relevant with the skills required by beauty salons. of productive courses taught in the school, courses can be applied and used by the salon staffs. there are just skills that are not used by beauty salons, namely traditional bun and hair pieces. in addition, the graduates lack hair cutting skills which are required by the industry. graduates of vocational education are expected to work in an industrial world that corresponds with their skills. vocational education is education that aims to ( ) make ends meet of communities for the labor market, ( ) to increase education choice for each individual, and ( ) to grow motivation to learn throughout life. evans & edwin ( ) adds that vocational education is a part of an education system that prepares individuals for the job or job groups. vocational education is all of type and form of learning experiences that help students to carry out their vocational development steps from identification, exploration, orientation, preparation, choosing and making a career in the workforce. it can be said that vocational education is education to enter the workforce and for everyone that needs it. the limits of vocational education show that vocational education is identical with the education of the world of work. the new graduates can be said competent if they have reached competency standards that determined by the school and the indonesian national competency standards. perseverance and abilities that had by students become the factor in determining the learning mastery besides normative and adaptive values. assessments of attitude, knowledge, and skill are put together to see the students can continue to the next step or not. for incompetent students cannot continue to the next competency. to reach the students’ competency, they must do their work optimally with or without a teacher. after the students have the competency, the students can ask the teacher to assess them about their competency and declared to be competent by the teacher. corresponding with the regulation of the indonesian minister of health, the students pass the primary and secondary education after accomplishing all learning programs, get minimum values either in the last assessment for all group courses, religion course and good attitude, nationality and personality, aesthetics course group, physical course group, sports, and health, pass the school exam for science and technology and pass the national exam (ministry of health, ). it means a productive course of hair beauty is divided into two namely the productive program and hair vocational competency productive program. the basic vocational productive program consists of ( ) services, ( ) anatomy and physiology, ( ) cosmetics, ( ) spa services, and ( ) osh. the hair beauty competency productive program course consisted of ( ) hair washing, ( ) hair drying, ( ) hair and scalp care, ( ) hair cutting, ( ) hairstyling, ( ) hair curling, ( ) hairpiece styling, ( ) hairstyling, ambiyar et al., relevance of the productive course of hair beauty in vocational high schools to industry needs jurnal pendidikan teknologi dan kejuruan,vol. , no. , may ( ) hair bun, ( ) traditional hair bun, ( ) barber techniques, ( ) hair dyeing, and ( ) hair straightening. therefore before graduating, all of the competencies must be had by the students. in addition, the techniques learned in the school are still basic and theoretical. it means that the goals of vocational education have not been achieved maximally. therefore, the students should be equipped with adequate knowledge and skills to enter the workforce by trainings or practices that correspond to the respective fields. the training is usually carried out in the last semester of grade xi which is also known as industrial practices. the partnership between the school and the industry can prepare the students effectively that correspond with industry needs (baser et al., ; nurmayani et al., ). the journal of smkn padang explains that an industrial practice is a training that demands quality of skills and competencies systematically and it is programmed between education in the school and the workforce. the implementation of industrial practices is conducted with certain procedures. the students are required to have the basic skills of the field before entering the workforce. the goal of industrial practices is to add knowledge obtained in the workforce and can apply knowledge from the learning process in schools in the real world of work. but in the fact, the students who passed the program cannot apply the skills in the work world to satisfy the industrial demands. therefore, the students must be trained completely during the industrial practices to increase the students’ ability. the location of industrial practices must be determined by the school appropriately so that the students can get the high quality industries to knowledge and experiences. the industrial staffs also can involve the students in doing the job at the beauty salon. the occurrence of a paradox in this study is caused by the results of a preliminary observation in which the researcher obtained data from two beauty salons and interviews the staffs. on the data of the study, the researcher carried out the interviews to the directors of beauty salons in padang city, so that the results obtained were different with the preliminary observation. conclusion the productive course of hair beauty learned by students in the school has corresponded with a syllabus in the curriculum of beauty therapy that teaches thirteen skills of the vocational basic productive program including theoretical and practical learning as well as character education. the students are expected to demonstrate occupational health and safety and be responsible for the practices. the graduates’ competency required by beauty salons in padang city is generally corresponded with the needs of the industry. of thirteen productive courses taught in the school, eleven courses can be applied and used in the workplaces. however, there are skills that less and not used namely traditional local bun and hairpieces. on the other hand, the skill that is not mastered by the students but is required by the industry is hair cutting. the school should be more concerned about students’ needs in the learning mainly in practical learning. the practical equipment and materials should cope with the development of the industry. the teachers should improve the students’ practical skills, so that they can be more competent in the industries, and the teachers should know the development of industrial worlds, to give the new knowledge to students. the industries should give recommendations as evaluation and feedbacks for the school and work collaboratively with the school to produce skilled middle-level workforce that satisfies the industry needs. references anaf. . badan pusat statistik. jakarta anastasia, h. . cantik, sehat dan sukses berbisnis spa. yogyakarta: kanisius baser, j.a., mat jizat, n., yunus, f.n., rahim, m.b., abdul razzaq, a. r., hasan, a. . competency of national dual training system industry advisors. jurnal pendidikan teknologi dan kejuruan.. . , - . djojonegoro, w. . peningkatan kualitas sumber daya manusia untuk pembangunan. jakarta: depdikbud evans, r. n. & edwin, l.h. . foundation of vocational education. columbus, ohio: charles e. merrill publishing company finch, c.r. & crunkilton, j.r. . curriculum development in vocational and technical education: planning, content, and implementation. sidney: allyn and bacon hakim, n. . pengetahuan tata kecantikan tingkat terampil. jakarta: indonesian department of education and culture hendayat, s. . pendidikan dan pembelajaran teori, permasalahan dan peraktek. malang: penerbit universitas muhhamadyah malang mangkunegaran, a.p. . perencanaan dan pengembangan sumber daya manusia. bandung: pt refika aditama marleni. . implementasi keterampilan lulusan program keahlian tata kecantikan smk negeri padang dalam bekerja pada industri salon kecantikan berklasifikasi utama. thesis. unpublished. universitas negeri padang masriam, bukit. . strategi dan inovasi pendidikan kejuruan. bandung: alfabeta melcalf, s. & bijan, yz. . berani memulai dan menjalankan bisnis salon kecantikan. jakarta: pt tiga serangkai miles, m.b. & huberman, a. m. . qualitative data analysis. translator: tjetjep rohendi rohidi. jakarta: ui press ministry of health. . peraturan direktur jenderal bina gizi dan kesehatan ibu dan anak nomor hk. . / b . / / tentang pedoman penyelenggaraan salon kecantikan di bidang kesehatan yang diterbitkan. jakarta: ministry of health of indonesia moleong, j. l. . metodologi penelitian kualitatif. edisi revisi. bandung: remaja rosdakarya mulyasa, e. . menjadi guru profesional menciptakan pembelajaran kreatif dan menyenangkan. bandung: rosda karya nurmayani, s., sugiarti, y., & mujdalipah, s. . application of a blended learning model in agricultural vocational high school. jurnal pendidikan teknologi dan kejuruan. . , - sadjad, r.s. . paradigma baru pendidikan tinggi untuk menciptakan sumber daya manusia unggulan. makasar: um sudjana, n. . penelitian dan penilaian pendidikan. bandung: sinar baru algesindo sugiyono. . metode penelitian kuantitatif, kualitatif dan r&d. bandung: alfabeta sumantri. . life skill yang tidak terpisahkan dari kurikulum. konvensi nasional pendidikan indonesia v ( ) hair bun, ( ) traditional hair bun, ( ) barber techniques, ( ) hair dyeing, and ( ) hair straightening. therefore before graduating, all of the competencies must be had by the students. in addition, the techniques learned in the school are still basic and theoretical. it means that the goals of vocational education have not been achieved maximally. therefore, the students should be equipped with adequate knowledge and skills to enter the workforce by trainings or practices that correspond to the respective fields. the training is usually carried out in the last semester of grade xi which is also known as industrial practices. the partnership between the school and the industry can prepare the students effectively that correspond with industry needs (baser et al., ; nurmayani et al., ). the journal of smkn padang explains that an industrial practice is a training that demands quality of skills and competencies systematically and it is programmed between education in the school and the workforce. the implementation of industrial practices is conducted with certain procedures. the students are required to have the basic skills of the field before entering the workforce. the goal of industrial practices is to add knowledge obtained in the workforce and can apply knowledge from the learning process in schools in the real world of work. but in the fact, the students who passed the program cannot apply the skills in the work world to satisfy the industrial demands. therefore, the students must be trained completely during the industrial practices to increase the students’ ability. the location of industrial practices must be determined by the school appropriately so that the students can get the high quality industries to knowledge and experiences. the industrial staffs also can involve the students in doing the job at the beauty salon. the occurrence of a paradox in this study is caused by the results of a preliminary observation in which the researcher obtained data from two beauty salons and interviews the staffs. on the data of the study, the researcher carried out the interviews to the directors of beauty salons in padang city, so that the results obtained were different with the preliminary observation. conclusion the productive course of hair beauty learned by students in the school has corresponded with a syllabus in the curriculum of beauty therapy that teaches thirteen skills of the vocational basic productive program including theoretical and practical learning as well as character education. the students are expected to demonstrate occupational health and safety and be responsible for the practices. the graduates’ competency required by beauty salons in padang city is generally corresponded with the needs of the industry. of thirteen productive courses taught in the school, eleven courses can be applied and used in the workplaces. however, there are skills that less and not used namely traditional local bun and hairpieces. on the other hand, the skill that is not mastered by the students but is required by the industry is hair cutting. the school should be more concerned about students’ needs in the learning mainly in practical learning. the practical equipment and materials should cope with the development of the industry. the teachers should improve the students’ practical skills, so that they can be more competent in the industries, and the teachers should know the development of industrial worlds, to give the new knowledge to students. the industries should give recommendations as evaluation and feedbacks for the school and work collaboratively with the school to produce skilled middle-level workforce that satisfies the industry needs. references anaf. . badan pusat statistik. jakarta anastasia, h. . cantik, sehat dan sukses berbisnis spa. yogyakarta: kanisius baser, j.a., mat jizat, n., yunus, f.n., rahim, m.b., abdul razzaq, a. r., hasan, a. . competency of national dual training system industry advisors. jurnal pendidikan teknologi dan kejuruan.. . , - . djojonegoro, w. . peningkatan kualitas sumber daya manusia untuk pembangunan. jakarta: depdikbud evans, r. n. & edwin, l.h. . foundation of vocational education. columbus, ohio: charles e. merrill publishing company finch, c.r. & crunkilton, j.r. . curriculum development in vocational and technical education: planning, content, and implementation. sidney: allyn and bacon hakim, n. . pengetahuan tata kecantikan tingkat terampil. jakarta: indonesian department of education and culture hendayat, s. . pendidikan dan pembelajaran teori, permasalahan dan peraktek. malang: penerbit universitas muhhamadyah malang mangkunegaran, a.p. . perencanaan dan pengembangan sumber daya manusia. bandung: pt refika aditama marleni. . implementasi keterampilan lulusan program keahlian tata kecantikan smk negeri padang dalam bekerja pada industri salon kecantikan berklasifikasi utama. thesis. unpublished. universitas negeri padang masriam, bukit. . strategi dan inovasi pendidikan kejuruan. bandung: alfabeta melcalf, s. & bijan, yz. . berani memulai dan menjalankan bisnis salon kecantikan. jakarta: pt tiga serangkai miles, m.b. & huberman, a. m. . qualitative data analysis. translator: tjetjep rohendi rohidi. jakarta: ui press ministry of health. . peraturan direktur jenderal bina gizi dan kesehatan ibu dan anak nomor hk. . / b . / / tentang pedoman penyelenggaraan salon kecantikan di bidang kesehatan yang diterbitkan. jakarta: ministry of health of indonesia moleong, j. l. . metodologi penelitian kualitatif. edisi revisi. bandung: remaja rosdakarya mulyasa, e. . menjadi guru profesional menciptakan pembelajaran kreatif dan menyenangkan. bandung: rosda karya nurmayani, s., sugiarti, y., & mujdalipah, s. . application of a blended learning model in agricultural vocational high school. jurnal pendidikan teknologi dan kejuruan. . , - sadjad, r.s. . paradigma baru pendidikan tinggi untuk menciptakan sumber daya manusia unggulan. makasar: um sudjana, n. . penelitian dan penilaian pendidikan. bandung: sinar baru algesindo sugiyono. . metode penelitian kuantitatif, kualitatif dan r&d. bandung: alfabeta sumantri. . life skill yang tidak terpisahkan dari kurikulum. konvensi nasional pendidikan indonesia v ambiyar et al., relevance of the productive course of hair beauty in vocational high schools to industry needs anal . darren bradley sleeping beauty: a note on dorr’s argument for / darren bradley beauty is about to be drugged, rendering her unconscious for a long time. during that time she will be awakened briefly, either once (on monday) or twice (on monday and tuesday). the number of awakenings depends on the toss of a fair coin: if the result is tails, she is awakened twice: if heads, once. the nature of the drug is that she will not remember being awake. in particular, when she is awakened, she will not know whether it is monday or tuesday. upon awakening on monday, what should her degree of belief be that the coin landed heads? the paradox is that there are compelling arguments for the answers of both / and / . cian dorr gives an argument by analogy that the correct analysis . , july , pp. – . © darren bradley a t u n ive rsity o f c a lifo rn ia , b e rke le y o n a u g u st , h ttp ://a n a lysis.o xfo rd jo u rn a ls.o rg d o w n lo a d e d fro m http://analysis.oxfordjournals.org sleeping beauty: a note on dorr’s argument for / answer is / . i will argue that his analogy is dissimilar in a crucial respect and as such is unhelpful to resolving the problem. dorr presents the following variation on the story( : – ): beauty is about to go to sleep for a long time. during that time she will be awakened briefly, twice, on monday and tuesday. a fair coin will be tossed, and what beauty can remember will depend on the result. if the coin lands tails, she will be given the same amnesia- inducing drug as was used in the original experiment. she will wake up twice, unable to tell if it is the first or second awakening. but if the coin lands heads, she will be given a weaker amnesia-inducing drug, which merely delays the onset of memories from the previous day, rather than destroying them completely. if beauty receives this weaker drug, the first minute of her awakening on tuesday will be just as it would have been if she had received the stronger drug, but after that the memories of monday’s awakening will come flooding back. she will realise that it is tuesday and that the outcome of the toss must have been heads. let p_ be beauty’s credence function immediately after being woken on monday in the variant case. we must assign credence for the following hypotheses: h the coin lands heads and it’s monday h the coin lands heads and it’s tuesday t the coin lands tails and it’s monday t the coin lands tails and it’s tuesday how should this credence be distributed? dorr claims, and i agree, that the only plausible answer is: p_(h ) = p_(t ) = p_(h ) = p_(t ) = / . let p be beauty’s credence function after a minute has passed on monday. assume she has not had the flooding back of memories she would have experienced had h been true, so p(h ) = . nothing in her experi- ence during the first minute does anything to discriminate between the other three hypotheses. so the ratio of her credence in h , t and t will remain unchanged. hence p(h ) = p(t ) = p(t ) = / ; so p(heads) = p(h ) = / . i agree with this reasoning. dorr then argues that there are no relevant differences between his variant case and the original case with respect to p(h ). i disagree. there is a crucial difference between beauty after a minute in the variant case and beauty after a minute in the original case. in the variant case, a certain pos- sibility has been eliminated. it could have turned out that it was heads and tuesday. not only could it have been heads and tuesday, beauty could have known it was heads and tuesday. she would have known this for certain if she had suddenly got a flood of memories from the previous day. a t u n ive rsity o f c a lifo rn ia , b e rke le y o n a u g u st , h ttp ://a n a lysis.o xfo rd jo u rn a ls.o rg d o w n lo a d e d fro m http://analysis.oxfordjournals.org darren bradley this flood of memories would have made heads more likely. the absence of this flood makes heads less likely. that is, she can conditionalize on the absence of a flood of memories and conclude that heads is less likely. while she was waiting for a possible flood of memories in that first minute, she had no new evidence about how the coin landed. if she got a flood of memories, she would increase the probability that the coin landed heads (to ). so in the absence of a flood of memories, she would have to decrease the probability that the coin fell heads. in the original case, there is no such possibility. there is no possibility that beauty will find out for certain that it fell heads. so she cannot update on the lack of such information. unlike in the variant case, beauty has no non-indexical information to conditionalize on. dorr asks why this delay of a minute, the only difference between the original sleeping beauty and the variant case should make any difference to subjective probabilities. i answer that in the variant case a hypothesis that could have been eliminated has failed to be (h ). there is no equiva- lent of this is in the original case. the variant case is uninformative. stanford university stanford, ca , usa dbradley@stanford.edu references dorr, c. . sleeping beauty: in defence of elga. analysis : – . i would like to thank branden fitelson for helpful discussion. a t u n ive rsity o f c a lifo rn ia , b e rke le y o n a u g u st , h ttp ://a n a lysis.o xfo rd jo u rn a ls.o rg d o w n lo a d e d fro m http://analysis.oxfordjournals.org mammalian mutagenesis using a highly mobile somatic sleeping beauty transposon system adam j. dupuy , keiko akagi , david a. largaespada , neal g. copeland & nancy a. jenkins transposons have provided important genetic tools for functional genomic screens in lower eukaryotes but have proven less useful in higher eukaryotes because of their low transposition frequency. here we show that sleeping beauty (sb), a member of the tc /mariner class of transposons, can be mobilized in mouse somatic cells at frequencies high enough to induce embryonic death and cancer in wild-type mice. tumours are aggressive, with some animals developing two or even three different types of cancer within a few months of birth. the tumours result from sb insertional mutagenesis of cancer genes, thus facilitating the identification of genes and pathways that induce disease. sb transposition can easily be controlled to mutagenize any target tissue and can therefore, in principle, be used to induce many of the cancers affecting humans, including those for which little is known about the aetiology. the uses of sb are also not restricted to the mouse and could potentially be used for forward genetic screens in any higher eukaryote in which transgenesis is possible. transposon-tagged mutagenesis has proven invaluable for functional genomic screens in organisms such as drosophila melanogaster , , caenorhabditis elegans and plants , but the lack of active elements in higher eukaryotes has precluded their use for mammalian functional genomics. this problem was partly solved when molecular recon- struction was used to produce a transposon, sleeping beauty (sb), that transposes in higher eukaryotic cells . there is much interest in these transposons as insertional mutagens because they have a small target site for integration (for sb, this is ta) and require few host cell factors for their activity. sb is a bipartite transposition system consisting of the transposase and transposon vector, which is flanked by the binding sites for the sb transposase, the so-called inverted repeats/direct repeats (irdrl (left) and irdrr (right)). transpo- sons are mobilized by sb transposase supplied in trans. sb is active in the mouse germ line – (one or two transpositions per animal born) and mouse somatic cells , but the transposition frequency is too low to be useful for most genetic screens . analysis of sb transposition integration sites cloned from the mouse germ line indicates that sb has fewer transposition site biases than retrotransposons, increasing its potential as an insertional mutagen , . however, sb does show a small but significant bias towards genes and their upstream regulatory sequences, although this bias is much less than that observed with retroviruses . sb elements are also not locked in place after transposition and can continuously transpose to new sites. these qualities would make sb an attractive insertional mutagen for functional genomic screens in higher eukaryotes if the frequency of transposition could be increased. a limitation of sb is that transposed elements tend to reintegrate at sites linked to the donor site. previous studies showed that – % of germline sb transpositions are located within – megabases of the donor site – . this problem can also be overcome by increasing sb transposition frequencies to levels in which local transposition is no longer rate limiting for genome-wide insertional mutagenesis. creating a highly active sb mutagenesis system to develop a more active eukaryotic sb transposition system we made several enhancements to the sb transposition system used previously. we generated a mutagenic transposon vector, t /onc (fig. a). this transposon is similar to that described by an accom- panying paper (ref. ) but contains a larger fragment of the engrailed- (en ) splice acceptor (sa) and is flanked by optimized sb transposase binding sites that increase sb transposition . it is also smaller than other sb transposons used previously (about . kilo- bases (kb)) and approaches optimal size for transposition . t /onc contains two splice acceptors and a bi-directional poly(a) and can terminate transcription when integrated in either orientation in a gene. it also contains a murine stem cell virus (mscv) long terminal repeat (ltr) and a splice donor (sd) and can promote gene expression when integrated upstream or within a gene. thirty t /onc transgenic founders were generated after microinjection. because sb transposes by a cut-and-paste mechanism, the number of transposons in the transgene concatomer can initially limit the number of transposition events. any methylation present on the transposon could also be transferred to new sites within the genome. methylation of the mscv promoter might therefore inhibit its ability to affect expression of neighbouring genes. with this in mind, founder transgenic animals were screened to determine their trans- poson copy number and the methylation status of the mscv promoter (fig. b, supplementary fig. ). three founder transgenic animals containing a high copy number of unmethylated transpo- sons ( , , ) were used to establish transgenic lines (fig. b). transposon concatomers from each line were transmitted articles mouse cancer genetics program, national cancer institute, center for cancer research, frederick, maryland , usa. department of genetics, cell biology and development, arnold and mabel beckman center for transposon research, the cancer center, university of minnesota, minneapolis, minnesota , usa. vol | july |doi: . /nature © nature publishing group at normal mendelian frequencies, and heterozygous mice showed no obvious phenotype. next, we generated a transposase knock-in allele to avoid the epigenetic silencing often seen with transgenes. to increase sb transposition we generated the knock-in by using the sb trans- posase . this transposase contains four amino acid substitutions that increase its activity above that of the sb transposase used previously. an expression cassette consisting of a splice acceptor site upstream of the sb complementary dna followed by an sv polyadenylation signal was targeted to the rosa locus to generate the rosasb allele (supplementary fig. ). this site was chosen because genes targeted to this locus are expressed ubiquitously during development and in adult mouse tissues. western blotting confirmed the expression of the sb transposase in rosasb mice (data not shown), and quantitative polymerase chain reaction (pcr) indicated that the rosasb allele is equally expressed in all tissues tested (brain, spleen, skin and lung) (data not shown). heterozygous rosasb mice were aged for more than a year and showed no obvious phenotype. rosasb mice were then crossed to each t /onc transgenic line to generate a cohort of mice harbouring both elements. unexpectedly, intercross offspring showed a non-mendelian inheritance pattern with a significant decrease in progeny inheriting both the rosasb transposase and the t /onc transgene. all three t /onc lines produced fewer double-transgenic progeny than expected, although the frequency varied between the lines (tg , / ( . %); tg , / ( . %); tg , / ( . %)). we proposed that this decrease in viability was due to lethality induced by sb transposition and/or dna damage that was not repaired after sb excision. previous studies with mice deficient for proteins involved in nonhomologous end joining indicate that lymphocytes and neurons are particularly sensitive to double-strand breaks during development , . to test this hypothesis, we characterized embryos at various developmental time points. normal frequencies of double-transgenic embryos were observed at embryonic day (e ), whereas a significant decrease was seen by e (fig. c). embryos at both time points seemed grossly normal, although many double-transgenic embryos seemed smaller than control littermates (fig. d). histopathological examination of double-transgenic embryos showed various develop- mental abnormalities unique to each embryo (data not shown). to determine whether sb transposition occurs in double- transgenic embryos, we asked whether sb transposons had been excised from transposon concatomers in double-transgenic embryos, because excision is the first step in transposition. bamhi sites are located within the plasmid sequences that flank each transposon in the concatomer and in the transposon itself (fig. e). consequently, any transposon in the concatomer will generate a -bp fragment by using the probe indicated. it is unlikely that bamhi sites will immediately flank a transposon after transposition. reintegrated transposons will therefore primarily generate bamhi fragments that are larger than bp. analysis of nine double-transgenic embryos showed that most transposons were excised from the concatomer by e (fig. e). analysis of the brain and kidney of ten adult double- transgenic animals showed that transposon excision continues in the adult, until by postnatal day virtually all of the transposons within the concatomer have been excised (fig. e). excision therefore begins early in development and continues into the adult, affecting virtually all cell types. previous studies showed that % of excised transposons re- integrate into the mouse genome . to confirm that excised transpo- sons reintegrate into the mouse genome we used ligation-mediated pcr (lm-pcr) to amplify sb junctions from ten double- transgenic embryos. lm-pcr is a powerful new amplification method that makes it possible to amplify and sequence thousands of sb transposition sites rapidly (supplementary methods). ninety- six sb junction fragments were picked randomly and sequenced from each amplified embryo library (supplementary table ). blast figure | analysis of double-transgenic embryos and adults. a, structure of the t /onc transposon. b, estimates of transgenic transposon copy number, and percentage of methylated transposons determined after digestion with drai–mspi or drai–hpaii. c, reduced number of e double-transgenic embryos and adults. d, double-transgenic embryos (left panel) were often smaller than control littermates. e, the -bp bamhi concatemer fragment (arrow) is reduced in intensity in double-transgenic embryos and adults relative to the t /onc heterozygous transgenic control. for adult tissues, brain dna is in the odd-numbered lanes and kidney dna is in the even-numbered lanes. articles nature|vol | july © nature publishing group searches of the independent transposon junctions showed that most junctions were rare and represented only once among the clones analysed (supplementary table ), indicating that each junc- tion is present in a limited number of cells. this is consistent with southern blot data, which showed no detectable newly acquired sb transposons in double-transgenic embryos (fig. e). sb transposons are therefore reintegrating into the mouse genome at many sites in double-transgenic mice. t /onc concatemer integration sites are located on chromo- somes , and (data not shown). as expected, we saw an increased frequency of transposons reintegrated on these chromosomes in double-transgenic embryos. the percentage of local transposition within a -megabase region varied from % to % in double- transgenic embryos (data not shown) in contrast to germline transpositions reported by others, in which – % of the transposi- tions were local – . even when transposons landed on the same chromosome as the transgene concatemer, the transposon inte- grations were well distributed across the chromosome and there was no easily defined local hopping interval. we speculate that the higher sb transposition frequencies obtained with our system permit secondary and tertiary rounds of transposition, which masks local transposition. this high rate could be attributed to a more optimal expression of the sb transposase from the rosasb allele. previous work has indicated that even moderate changes in sb transposase expression can have a significant impact on transposition frequency . sb transpositions in the embryo are fairly well distributed across the genome. when t /onc integrated in or near a gene there was little preference for a gene region or orientation relative to the nearest gene (supplementary tables and ). only four regions in the genome (less than kb in size) contained two sb transposon integrations in independent embryos (supplementary table ), which is similar to the number ( ) predicted by monte carlo simulations for random integration, and no region (less than kb in size) contained three sb transposon integrations. the embryo data therefore seem to represent a population of unselected transposon integrations. double-transgenic mice are tumour-prone twenty-four double-transgenic mice that survived to weaning were monitored for tumour development. at weeks of age the mice began to show signs of illness, and by weeks all the mice had died from cancer (fig. a). multiple tumour types were identified: the most common tumour was t-cell lymphoma (fig. b). tumour cells were frequently found in all tissues of the animal and in some cases a single animal developed two or even three different cancer types (fig. b). haematopoietic tumours predominated, possibly reflect- ing the large pool of haematopoietic stem cells present in mice. medulloblastoma, a solid tumour of the cerebellum, was also observed in two mice; intestinal and pituitary neoplasia was seen in other animals. thus, unlike retroviral insertional mutagenesis, sb mutagenesis is not limited to the haematopoietic system. stained sections of the medulloblastoma from animal tg - (fig. a, c) and a corresponding normal cerebellum (fig. b, d) showed that the normal morphology of the cerebellum was dis- rupted, with tumour cells invading the molecular layer (fig. a). tumour tissue also extended down the brain stem and could be seen adjacent to the spinal cord (fig. c). this is similar to what is observed in human medulloblastoma. bamhi-digested tumour dnas were subsequently analysed by figure | adult double-transgenic mice die from cancer. a, survival curves showing decreased viability of double-transgenic mice: yellow, rosasb; blue, t /onc ; red, double-transgenic. b, age at death and tumour type of double-transgenic mice. c, southern analysis of bamhi-digested tumour dna. each band represents a separate sb transposon integration. ln, lymph node; m, mass; sp, spleen; th, thymus. nature|vol | july articles © nature publishing group southern blotting to determine whether they contained clonal or subclonal sb transpositions. as expected, southern blotting failed to identify clonal, somatically acquired transposon integrations in tail dna (fig. c, lane ) or in dna from normal brain and kidney (fig. e). in contrast, numerous clonal and subclonal transposon integrations were seen in lymph nodes, spleen and thymus in tumour dna (fig. c, lanes – ). the pattern of transposon integrations in different tumour tissues from the same animal was similar but not identical (fig. c, lanes – , and ), indicating that some transpositions are lost while others are gained during tumour development. these results are consistent with insertional mutagenesis of cancer genes as the disease-inducing mechanism. analysis of sb integration sites in tumour dna to confirm that these tumours are induced by insertional muta- genesis, we cloned and analysed sb junctions from tumours (supplementary table ). in contrast to the results from embryos (supplementary table ), we identified multiple genes that were mutated by sb integration in two or more tumours (supplementary table ). these results are unlikely to have occurred by chance. seven of these genes are validated human cancer genes, and a further seven are mutated by retroviral integration in mouse leukaemias (http:// rtcgd.ncifcrf.gov). we also identified four genes that were mutated more than once in the same tumour (two notch integrations (tg - ), two jak integrations (tg - ), two csf r integrations (tg - ), two erg integrations (tg - ) and three erg integrations (tg - )) (supplementary table ). this could reflect tumour microheterogeneity, with the different integrations occurring in different subpopulations of tumour cells during tumour progression. we also identified inte- grations in several genes that have not yet been examined for a role in human cancer but which represent excellent disease gene candidates (supplementary table ). like the embryo integrations, tumour integrations were widely distributed across the genome with little local hopping (data not shown). however, integrations in tumour dna located upstream or within genes showed an orientation bias that was not found in embryo integrations (supplementary table ). in tumours, % of transposons located of genes are in the same transcriptional orientation as the gene, compared with % for integrations in embryos (p , . ). in addition, % of transposons located within genes are in the same orientation, compared with % for integrations in embryos (p , . ). unlike retroviruses, which have strong enhancer activity and can activate gene expression over large distances, t /onc seems to have little enhancer activity. this is supported by our failure to identify common integration sites in which transposons are integrated downstream of the gene (sup- plementary table ) and by recent data showing that sb transposons that lack viral ltr and corresponding sd sequences fail to increase the expression of nearby genes significantly . consequently, t /onc primarily activates gene expression by integrating upstream of a gene or in an upstream intron and promoting the expression of the gene from the mscv ltr, or by integrating into the coding region and either promoting the expression of a truncated protein or truncating the transcript prematurely (supplementary table ; data not shown). this lack of enhancer activity greatly simplifies the identification of cancer genes mutated by sb. activating notch transpositions activating notch mutations have been identified in more than % of human t-cell acute lymphoblastic leukaemia (t-all) cell lines . among ten sb-induced t-cell lymphomas analysed, six contained sb integrations in intron of notch (fig. a, sup- plementary table ). these transposon integrations mapped to three different sites in intron , indicating that transposition is not totally random or that integration at these sites is selected because of their effect on notch expression. all six integrations are oriented in the same transcriptional direction as notch and induce the expression of a notch fusion transcript containing the mscv promoter and the figure | medulloblastoma pathology. sections of an sb-induced medulloblastoma and control cerebellum, stained with haematoxylin and eosin. a, section of the cerebellum from animal tg - showing normal morphology, with the purkinje cell layer (p) adjacent to the granule cell layer (gr). tumour cells (t) have invaded the molecular layer (ml). b, comparable section for a normal cerebellum. c, tumour (t) has grown down the brain stem adjacent to the spinal cord. d, comparable section for a normal spinal cord. figure | analysis of notch integrations. a, structure of mutated notch allele in sb-induced t-cell leukaemias. white, exons; grey, transposon irdrs; red, transposon splice acceptor; blue, splice donor; arrows, primer binding sites (f, forward; r, reverse). b, northern analysis using a notch cdna probe showed that all tumours with notch integrations (lanes – ) express a truncated notch transcript. the transcript in tumour is less intense but can be seen on longer exposure. wt, wild type. c, rt–pcr shows that only tumours with notch integration express a truncated notch transcript. the sequence of the sb-notch splice junction in tumours is shown below. articles nature|vol | july © nature publishing group end of notch (fig. b, c). this fusion transcript mimics that seen in human t-all patients with t( ; ), in which the translocation drives expression of an activated notch carboxy-terminal protein fragment . furthermore, transgenic mice overexpressing a similar fragment of notch develop t-cell lymphoma . these results confirm that sb-induced tumours are induced by insertional mutagenesis. cooperating cancer genes and pathways among the six tumours with activating integrations at notch , three also had activating integrations upstream of rasgrp (fig. , sup- plementary table ), a gene that positively regulates ras signalling. the probability of finding two tumours with integrations in the same two pair of genes by chance is low (p ¼ . £ ; supplementary methods). integrations in rasgrp were seen only in tumours with notch integrations, indicating that ras signalling might cooperate with notch in tumour induction. two tumours with notch and rasgrp integrations also had activating integrations upstream of sox , an uncharacterized member of the sox family of sry-related high-mobility-group (hmg)-box dna-binding proteins (fig. ). the probability of finding two tumours with integrations in notch , rasgrp and sox by chance is exceedingly low (p ¼ . £ ) and indicates that sox could represent another signalling pathway that cooperates with notch in tumour induction. finally, two notch tumours also have activating integrations upstream of runx (fig. ), indicating that runx might represent yet another notch -cooperating gene. although most genes mutated by sb transposition in tumours were identified in only one tumour, several belong to related signalling pathways. careful annotation identified seven pathways that were commonly disrupted in sb-induced tumours (supplemen- tary table ). similar analysis of the integration sites cloned from embryos did not reveal any similar trends. integrations in most cases are predicted to affect a given pathway in a similar manner, but they accomplish this through the disruption of different genes. for example, six tumours have transposon-induced mutations that are predicted to result in decreased tnf signalling. similarly, decreased rates of receptor recycling, increased signalling through the ras superfamily, increased jak/stat signalling and increased wnt signalling are all common pathways affected by sb transposition in tumours (supplementary table ). the identification of genes and signalling pathways that cooperate to induce cancer will make it possible to develop better combinatorial therapies for treating human cancer. discussion we describe here a non-viral insertional mutagen that efficiently induces tumours in wild-type mice. sb transposition can easily be controlled to mutagenize a specific target tissue by simply restricting the site of sb transposase expression. in principle, sb transposition can be adapted to generate virtually any kind of cancer by restricting the sites or timing of transposase expression. this should also reduce or eliminate the embryonic death observed in our studies, in which the sb transposase was widely expressed. the high frequency of transposition possible with our system might also prove valuable in generating tumours in other cell types and in wild-type genetic backgrounds that do not carry a predisposing cancer mutation. this will make it possible to model various types of human cancer without any knowledge of the causative events and in a more unbiased manner. together with high-throughput lm-pcr, cancer genes and their pathways associated with tumorigenesis can be rapidly identified, providing insight into human cancer through the use of mouse models. given the unexpectedly high somatic sb transposi- tion frequencies achieved in our studies, there is no theoretical reason why sb transposition frequencies cannot be increased in the mouse germ line to levels that would permit efficient forward genetic screens with sb. because sb tags the mutated gene, the gene is much easier to clone than one mutated by a point mutagen such as ethylnitrosourea. finally, the uses of sb are also not restricted to the mouse. sb was originally isolated from fish and has already been shown to function in zebrafish and medaka . sb could therefore be used in forward genetic screens in any higher eukaryote in which transgenesis is possible. methods generation of the rosasb allele. an expression cassette consisting of an en splice acceptor, sb cdna and sv poly(a) was cloned upstream of a floxed pgkneo cassette. this cassette was then recombined into a plasmid containing a tk selection cassette as well as the promoter region, exon and a portion of the single intron of the rosa locus by using the recombineering strategy described previously . this recombination introduced the knock-in cassette into the xbai site of the rosa intron that has been used in previous rosa knock-in alleles . the targeting plasmid was then linearized and introduced into es cells. after selection, es cell colonies were picked and dna was extracted and digested with spei to screen the region of rosa and bgli for the region. southern blotting was performed on the regionwith the use of a -bp saci fragment of the rosa promoter region. a -bp sspi fragment derived from the intron of rosa was used to confirm the recombination site by southern blot analysis. three independent clones were injected into blastocysts to derive three rosasb knock-in lines. mice were genotyped by pcr with primers specific for the sb cdna: -atgggaaaatcaaaagaaatcagccaag- and -gccaaa cagttctatttttgtttcatcagacca- . one line was subsequently main- tained by backcrossing to c bl/ mice. generation of t /onc transgenic mice. the t /onc transposon was made by replacing the hpai/bglii fragment containing the en splice acceptor from pt /onc with a fragment containing a larger portion of the en exon. in addition to this change, the overall size of t /onc was reduced ( , bp, compared with , bp for t /onc) but was otherwise identical to t /onc. the figure | notch cooperating genes. a, clonality of notch , rasgrp , sox and runx integrations in notch tumours was determined by southern analysis. b, c, quantitative pcr was used to measure the expression levels of rasgrp (b) and runx (c) in tumours relative to a glyceraldehyde- - phosphate dehydrogenase gene, gapdh control. results are means ^ s.d. for three independent assays. error bars in c are too small to show. quantitative pcr could not be reliably performed on sox ; sox expression in tumours with sox integrations was therefore monitored by rt–pcr (data not shown). nature|vol | july articles © nature publishing group pt /onc plasmid was linearized using scai and prepared for microinjection into (b c )f hybrid embryos with standard techniques. tail biopsy dna from founder animals was screened by southern blotting using an en splice acceptor probe. transgenic lines were established by crossing to c bl/ . offspring were genotyped by pcr using primers -cagttgaagtcggaagttta- and -ggaattgtgatacagtgaat- . calculation of expected number of common sites. a java program was created to simulate the random sb transposon insertions in the mouse genome. the program randomly selected (number of sites cloned from embryos) or (number of sites cloned from tumours) ta motifs from the whole mouse genome by using a random number generator. the program then counted the number of common integration sites by calculating distances between the integration sites. after repetition of this procedure , times, the average expected number of common integration sites was determined. received february; accepted april . . spradling, a. c. et al. gene disruptions using p transposable elements: an integral component of the drosophila genome project. proc. natl acad. sci. usa , –- ( ). . bellen, h. j. et al. p-element-mediated enhancer detection: a versatile method to study development in drosophila. genes dev. , –- ( ). . plasterk, r. h. the tc /mariner transposon family. curr. top. microbiol. immunol. , –- ( ). . osborne, b. i. & baker, b. movers and shakers: maize transposons as tools for analyzing other plant genomes. curr. opin. cell biol. , –- ( ). . ivics, z., hackett, p. b., plasterk, r. h. & izsvak, z. molecular reconstruction of sleeping beauty, a tc -like transposon from fish, and its transposition in human cells. cell , –- ( ). . dupuy, a. j., fritz, s. & largaespada, d. a. transposition and gene disruption in the male germline of the mouse. genesis , –- ( ). . horie, k. et al. efficient chromosomal transposition of a tc /mariner-like transposon sleeping beauty in mice. proc. natl acad. sci. usa , –- ( ). . fischer, s. e., wienholds, e. & plasterk, r. h. regulated transposition of a fish transposon in the mouse germ line. proc. natl acad. sci. usa , –- ( ). . carlson, c. m. et al. transposon mutagenesis of the mouse germline. genetics , –- ( ). . luo, g., ivics, z., izsvak, z. & bradley, a. chromosomal transposition of a tc /mariner-like element in mouse embryonic stem cells. proc. natl acad. sci. usa , –- ( ). . horie, k. et al. characterization of sleeping beauty transposition and its application to genetic screening in mice. mol. cell. biol. , –- ( ). . yant, s. r. et al. high-resolution genome-wide mapping of transposon integration in mammals. mol. cell. biol. , –- ( ). . collier, l. s., carlson, c. m., ravimohan, s., dupuy, a. j. & largaespada, d. a. cancer gene discovery in solid tumours using transposon-based somatic mutagenesis in the mouse. nature doi: . /nature (this issue). . cui, z., geurts, a. m., liu, g., kaufman, c. d. & hackett, p. b. structure–- function analysis of the inverted terminal repeats of the sleeping beauty transposon. j. mol. biol. , –- ( ). . geurts, a. m. et al. gene transfer into genomes of human cells by the sleeping beauty transposon system. mol. ther. , –- ( ). . gao, y. et al. a critical role for dna end-joining proteins in both lymphogenesis and neurogenesis. cell , –- ( ). . barnes, d. e., stamp, g., rosewell, i., denzel, a. & lindahl, t. targeted disruption of the gene encoding dna ligase iv leads to lethality in embryonic mice. curr. biol. , –- ( ). . wu, x., li, y., crise, b. & burgess, s. m. transcription start regions in the human genome are favored targets for mlv integration. science , –- ( ). . weng, a. p. et al. activating mutations of notch in human t cell acute lymphoblastic leukemia. science , –- ( ). . ellisen, l. w. et al. tan- , the human homolog of the drosophila notch gene, is broken by chromosomal translocations in t lymphoblastic neoplasms. cell , –- ( ). . beverly, l. j. & capobianco, a. j. perturbation of ikaros isoform selection by mlv integration is a cooperative event in notch(ic)-induced t cell leukemogenesis. cancer cell , –- ( ). . davidson, a. e. et al. efficient gene delivery and gene expression in zebrafish using the sleeping beauty transposon. dev. biol. , –- ( ). . grabher, c. et al. transposon-mediated enhancer trapping in medaka. gene , –- ( ). . liu, p., jenkins, n. a. & copeland, n. g. a highly efficient recombineering- based method for generating conditional knockout mutations. genome res. , –- ( ). . soriano, p. generalized lacz expression with the rosa cre reporter strain. nature genet. , –- ( ). supplementary information is linked to the online version of the paper at www.nature.com/nature. acknowledgements we thank d. swing and r. koogle for generating the t /onc transgenic mice and maintaining all mouse strains, and e. southon and s. reed for generating mice carrying the rosasb knock-in allele. this research is supported by the department of health and human services, national institutes of health and the national cancer institute. author information reprints and permissions information is available at npg.nature.com/reprintsandpermissions. the authors declare competing financial interests: details accompany the paper on www.nature.com/nature. correspondence and requests for materials should be addressed to n.a.j. (jenkins@ncifcrf.gov). articles nature|vol | july © nature publishing group chromosome painting with h identifies three bovine chromosomes (c , c , c ) and two porcine chromosomes (p , p ). an indirect chain of reasoning suggests that h /c and h /c were linked in the minotaur. ghr maps to h /c /p /m /r whereas hmgcr m sleeping beauty in a grain of rice the harvard community has made this article openly available. please share how this access benefits you. your story matters citation haig, david. . “sleeping beauty in a grain of rice.” biol philos (august ). doi: . /s - - - . published version doi: . /s - - - citable link http://nrs.harvard.edu/urn- :hul.instrepos: terms of use this article was downloaded from harvard university’s dash repository, and is made available under the terms and conditions applicable to open access policy articles, as set forth at http:// nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of- use#oap http://osc.hul.harvard.edu/dash/open-access-feedback?handle=&title=sleeping% beauty% in% a% grain% of% rice&community= / &collection= / &owningcollection / &harvardauthors= e d e c d dfb b f bd e d &departmentorganismic% and% evolutionary% biology http://nrs.harvard.edu/urn- :hul.instrepos: http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#oap http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#oap http://nrs.harvard.edu/urn- :hul.instrepos:dash.current.terms-of-use#oap sleeping beauty in a grain of rice david haig department of organismic and evolutionary biology, harvard university, oxford street, cambridge ma . phone: - - - fax: - - - e-mail: dhaig@oeb.harvard.edu acknowledgments lucas mix brought the sleeping beauty problem to my attention. carl veller patiently explained thirder reasoning and critically read the manuscript. ned hall and the anonymous reviewers provided valuable input. abstract in the sleeping beauty problem, beauty is woken once if a coin lands heads or twice if the coin lands tails but promptly forgets each waking on returning to sleep. philosophers have divided over whether her waking credence in heads should be a half or a third. beauty has centered beliefs about her world and about her location in that world. when given new information about her location she should update her worldly beliefs before updating her locative beliefs. when she conditionalizes in this way, her credence in heads is a half before and after being told it is monday. in applications of dutch book arguments to the sleeping beauty problem, the probability of a particular outcome has often been confounded with consequences of that outcome. heads and tails are equally likely but twice as much is at stake if the coin falls tails because beauty is fated to make the same choice twice. as a consequence, the possibility of tails should be given twice the weight of the possibility of heads when deciding whether to bet on heads even though heads and tails are equally likely. keywords sleeping beauty; hamilton’s rule; credence; relatedness; endosperm; conditionalization; de se beliefs elga ( ) introduced the sleeping beauty problem as a paradigm for thinking about centered beliefs. in this puzzle, beauty is uncertain whether a fair coin landed heads or tails. if the coin landed heads then she will be woken once. if the coin landed tails, then she will be woken twice. beauty is assumed to understand the procedure but to have all memories of waking erased on returning to sleep. what should be her waking credence that the coin landed heads? ‘thirders’ believe the answer is one-third because beauty is woken twice as often after the coin lands tails as after heads (elga ; hitchcock ; briggs ). ‘halfers’ believe the answer is one-half because the coin is equally likely to land heads or tails (lewis ; arntzenius ; meacham ). halfers and thirders continue to lock swords at the time of writing. the purpose of this paper is to offer a resolution of the sleeping beauty problem informed by consideration of a parallel problem in botany that arose in the s in which some theoreticians adopted a ‘thirder’ stance and others a ‘halfer’ stance. this problem concerned the genetic constitution of endosperm, a tissue within seeds. my understanding of the philosophers’ problem was clarified by thinking about the botanical problem and vice versa. philosophical disagreement between halfers and thirders may seem abstruse to empirical scientists and the genetics of endosperm may seem equally omphaloscopic to philosophers until it is noted that every grain of rice, wheat, rye, oats, barley, millet, sorghum, and maize is predominantly endosperm. most calories in the global human diet come from the direct consumption of endosperm or its indirect consumption via eating grain-fed beasts. epistemology can be practical. i propose that sleeping beauty should update her beliefs about her world before updating her beliefs about her location in that world and when she does this she maintains a consistent credence of one half in heads. the next two sections, eternal beauty and ephemeral beauty, present the argument which is summarized in beauty at rest. gambling on beauty offers an explanation of why arguments based on the bets beauty would accept on particular outcomes have often appeared to support the thirder position. hamilton’s wager and subsequent sections present the sleeping beauty problem as instantiated within a grain of rice. eternal beauty consider an infinite variant of the sleeping beauty problem. eternal beauty is told that she will be put to sleep and woken on every monday for eternity if a fair coin lands heads but on every monday and tuesday for eternity if the coin lands tails. on waking she will be told neither the day nor the outcome of the coin toss, and she will forget each and every waking on returning to sleep. before being put to sleep for the first time, she understands the protocol and she retains her understanding of the protocol at each awakening. she believes in three possibilities on waking: the coin landed heads and this is monday (h ), the coin landed tails and this is monday (t ), or the coin landed tails and this is tuesday (t ). eternal beauty’s beliefs about her world should be distinguished from her beliefs about her location in her world. i will call the former her worldly beliefs (p') and the latter her locative beliefs (p). she believes p'(heads) = p'(tails) = ½. if the coin lands heads, then her world contains h , p'(h ) = ½. if the coin lands tails, then her world contains t and t , p'(t ) = p'(t ) = ½. p'(t ) and p'(t ) are duplicates of the probability of her possible world in which the coin landed tails. eternal beauty knows she will wake on mondays, p'(h ) + p'(t ) = , and believes she has a half chance of waking on tuesdays, p'(t ) = ½. locative beliefs are de se beliefs. worldly beliefs are not otherworldly beliefs. they are beauty’s centered beliefs about her actual world and what it might be. if her actual world is conceived as an object with properties, then wordly beliefs might be considered de re (but i am ill-educated on the philosophical nuances of these latin phrases). how should eternal beauty convert beliefs about her world into beliefs about her location in her world? if she is in a world with t wakings then she must also be in a world with t wakings, namely p'(t |t ) = p'(t |t ) = . however, t and t are mutually exclusive when she wakes, p(t |t ) = p(t |t ) = . she believes her world contains either h or (t and t ) but, on waking, is located in h or t or t . how should she conceptualize this peculiar transformation of (t and t ) into (t or t )? halfers believe that waking on monday is twice as likely in possible worlds created by the coin landing tails as in possible worlds created by the coin landing heads. eternal beauty reasons on waking that either the coin landed heads or the coin landed tails. if the coin landed heads, with probability p(heads) = ½, then it is monday (h ), but if the coin landed tails, with probability p(tails) = ½, then it is either monday (t ) or tuesday (t ). since p(t ) = p(t ), by a principle of indifference, eternal beauty’s locative beliefs on waking are p(h ) = ½, p(t ) = ¼, p(t ) = ¼. thirders believe that eternal beauty is woken twice as often in possible worlds created by the coin landing tails as in possible worlds created by the coin landing heads. as a corollary thirders believe that eternal beauty is woken on monday just as often when the coin lands heads as when the coin lands tails. because h , t , and t occur equally often, she believes p(h ) = p(t ) = p(t ) = / and, therefore, p(heads) = / . for halfers, t and t collectively have the same locative probability as h on waking but, for thirders, t and t individually have the same locative probability as h . halfers believe, and thirders probably agree, that the likelihood that a waking is on monday in possible worlds in which the coin lands heads is twice the corresponding likelihood in possible worlds in which the coin lands tails. thirders also believe that waking on monday occurs as often in her possible world in which the coin lands heads as in her possible world in which the coin lands tails. in reasoning across these possible worlds, halfers use the likelihood of monday but thirders use the frequency of monday. what if you asked eternal beauty about her beliefs? perhaps she would say that whether her world was created heads or tails, whether it is monday or tuesday, or whether there are any other days but this day, are metaphysical questions because there is nothing she can learn to distinguish among the alternatives. she has a memory that p'(heads) = ½ from before the procedure—was it yesterday?—but lives in an eternal present. why should she have prior beliefs if nothing is at stake? possible worlds in which the coin toss was heads or the coin toss was tails are both infinite sets of indistinguishable days, without past or future, in eternal recurrence. if she were a number theorist, beauty might consider the proposition ‘one countable infinite set has twice as many members as another’ to be meaningless. ephemeral beauty eternal beauty’s sister, ephemeral beauty, is told on sunday that a fair coin will be tossed. if it comes up heads she will be woken on monday, and then made to forget, but if it comes up tails she will be woken on monday and tuesday, and made to forget after each waking. she will then be woken and debriefed on wednesday. this is the original sleeping beauty problem. the halfer can simply argue that, when ephemeral beauty is woken on monday or tuesday, her beliefs are the same as she possessed before the procedure. she believes p(heads) = ½ on sunday before the coin was tossed and believes the same on wednesday before the outcome of the coin toss is revealed. it would be perverse for her to believe anything different on monday or tuesday. a thirder must argue that ephemeral beauty believes tails to be twice as likely as heads on monday and tuesday despite contrary beliefs on sunday and wednesday. elga ( ) and lewis ( ) updated ephemeral beauty’s beliefs using standard conditionalization but different priors. they agreed that p(heads) = p(h ), that p(t ) = p(t ), and that when she is told it is monday her credence in heads should increase because the prior possibility of t is eliminated. this led each to adopt positions they found counterintuitive. elga ( ) reasoned that pmon(heads) = ½ and working backward was forced to conclude that p(heads) = / . by contrast, lewis ( ) assumed p(heads) = ½ and by working forward was forced to conclude that pmon(heads) = / . both reasoned that, before being told it is monday, sleeping beauty believes p(h ) + p(t ) + p(t ) = but, after being told it is monday, she believes pmon(h ) + pmon(t ) = . the probability formerly attached to t was distributed between h and t . for elga, beauty’s centered beliefs changed from p(h ) = p(t ) = p(t ) = / to pmon(h ) = pmon(t ) = ½, pmon(t ) = . for lewis, beauty’s centered beliefs changed from p(h ) = ½, p(t ) = ¼, p(t ) = ¼ to pmon(h ) = / , pmon(t ) = / , pmon(t ) = . elga and lewis conditionalized ephemeral beauty’s locative beliefs after learning it is monday from her prior locative beliefs before learning it is monday. but what if ephemeral beauty first updated her worldly beliefs before updating her locative beliefs? on waking, her worldly beliefs are p'(h ) = p'(t ) = p'(t ) = ½ but, on being told it is monday, she learns her possible worlds for this day do not include tuesday, p'mon(t ) = . therefore, p'mon(h ) = p'mon(t ) = ½ and pmon(h ) = pmon(t ) = ½. the duplicate probability of her worldly beliefs ‘evaporates’ when she is told it is monday. the locative probability formerly attached to t is transferred to t . ephemeral beauty is a ‘double-halfer’ who believes both p(heads) = ½ and pmon(heads) = ½ (bostrom ; meacham ). the information it is monday tells her nothing about the coin toss and does not change her credence in heads. the above procedure differs from standard conditionalization in how it handles duplicate probability as instantiated in p'(t ) and p'(t ). if new information eliminates one (but not all) of the duplicates, then her other worldly beliefs are unaffected: p'(t ) = ½ conditionalizes to p'mon(t ) = but p'(h ) and p'(t ) remain unchanged. p'(tails) was formerly represented redundantly by p'(t ) and p'(t ) but is now represented solely by p'mon(t ). when worldly beliefs are converted to locative beliefs, p'(tails) = ½ is distributed among the uneliminated duplicates, in this case to the single remaining option p(t ) = ½. all beauty learns on being told that it is monday is that it is not tuesday. she learns nothing about the toss of the coin. a simple reframing of her prior beliefs may make this claim more intuitive: (i) beauty believes she will be woken on monday, p'(monday) = ; (ii) beauty believes she will be woken on tuesday only if the coin lands tails, p'(tuesday|heads) = ; and (iii) beauty believes the coin is fair, p'(heads) = ½. when told it is monday she learns that this is the first time she has woken but she learns lewis ( ) might have said that when beauty is told it is monday, she learns something about her location in ordinary space that changes her location in logical space. her propositional attitude changes from ‘week in which heads or tails’ to ‘monday in which heads or tails.’ ‘waking on tuesday’ is a property of the first propositional attitude that does not have a counterpart in the second propositional attitude. this procedure appears similar to, perhaps is the same as, meacham’s ( , p. ) compartmentalized conditionalization. nothing about whether she will wake the next day. that possibility is still in the future depending on an unknown flip of the coin. beauty at rest beauty knows what she believes to be true. at each particular sentient moment, beauty has beliefs about her world associated with worldly probabilities (p') and beliefs about her location in that world associated with locative probabilities (p). worldly and locative probabilities may be primary probabilities, based on things she knows, or derivative probabilities, based on primary probabilities. on waking, beauty knows the coin to be fair and believes that either the coin landed heads or the coin landed tails. p'(heads) = p'(tails) are her primary worldly probabilities of her possible worlds. beauty also believes that if the coin landed heads then she will wake on monday (h ) but if the coin landed tails she will wake on monday (t ) and tuesday (t ). p'(h ) = p'(t ) = p'(t ) = ½, are her derived worldly probabilities where p'(h ) is derivative of p'(heads) and p'(t ) and p'(t ) are derivative of p'(tails). p'(t ) and p'(t ) are duplicate worldly probabilities. if the coin lands tails, both occur in beauty’s world. she knows that she wakes on monday because p'(h ) + p'(t ) = , but believes she has a half chance of waking on tuesday, because p'(t ) = ½. beauty’s locative beliefs have the same probability as her corresponding worldly beliefs except for duplicate derived probabilities in which case the primary probability is divided among the duplicates in locative beliefs. thus for the non-duplicate probabilities p'(heads) → p(heads), p'(tails) → p(tails), p'(h ) → p(h ), but for the duplicate probabilities p'(tails) → p(t ) = p(t ) = ¼. beauty’s worldly beliefs on waking are p'(h ) = p'(t ) = p'(t ) = ½ and her locative beliefs are p(h ) = ½, p(t ) = p(t ) = ¼. when information is provided relevant to her locative beliefs, beauty first updates p' before updating p. thus, on being told it is monday, beauty updates her worldly beliefs, eliminating the possibility of tuesday, and then uses her new worldly beliefs to update her locative beliefs: {p'mon(h ) = ½, p'mon(t ) = ½, p'mon(t ) = } → {pmon(h ) = ½, pmon(t ) = ½, p mon(t ) = } p'mon(heads) = ½ → pmon(heads) = ½. gambling with beauty an experimental economist remained unconvinced by such philosophical arguments. from his perspective, ephemeral beauty’s beliefs are no less metaphysical than eternal beauty’s beliefs if they have no material consequences. he commanded the research budget of an economist rather than a philosopher and proposed that the only way to understand credences is for subjects to have something at stake. for this purpose, he recruited many beauties to undergo the sleeping beauty procedure or a minor variant thereof. first, he assessed his recruits’ beliefs prior to the procedure. he reasoned that, if the beauties were risk-neutral gamblers, they would accept bets on heads with payout b for stake c whenever rb – c > , or c/b < r, where r was their credence in heads. the economist found that the beauties accepted bets on heads for c/b < ½ but rejected bets for c/b > ½. he therefore concluded they believed p(heads) = ½. all beauties were told that, each time they woke, they would be offered a series of bets on heads with different values of b and c to probe their beliefs about p(heads). their stakes would be collected and their winnings paid on wednesday. if a coin landed heads, then they would be woken on monday. if the coin landed tails, then they would be woken on monday and tuesday. at each waking, they would be told neither the outcome of the coin toss nor the day and their memories of waking would be erased on returning to sleep. the beauties were then assigned to one of two groups. or-beauties were told that, if the coin landed heads, their bets on monday would be honored, but, if the coin landed tails, only their bets on monday or tuesday would be honored (with the choice of monday or tuesday determined by an independent toss of the same coin). and- beauties were told that all bets would be honored. if the coin landed heads, their bets on monday would be honored, but, if the coin landed tails, their bets on monday and tuesday would be honored. or-beauties used the same decision rule during the procedure as they used before the procedure, c/b < ½. they continued to believe p(heads) = ½ on waking. the entire experimental rigmarole could have been avoided. it changed nothing of relevance. and-beauties, by contrast, adopted the decision rule c/b < / during the procedure. they seemed to believe that p(heads) = / . however, when the economist came to settle his accounts on wednesday he realized he had misunderstood their pecuniary incentives. heads and tails were equally likely. for each accepted wager, he paid b for stake c to all beauties for whom the coin landed heads and received c from or-beauties for whom the coin landed tails (as he had anticipated). however, he received c from and-beauties for whom the coin landed tails. he had erred when using and-beauties’ choices of wagers to assess their credence in heads because the outcome of the coin toss not only determined whether they won their bet but also the expected cost of the bet. in deciding whether to accept a wager on heads, and-beauties must take account not only of the probability of heads but also of the increased cost if the coin lands tails. or-beauties and and-beauties had been offered different wagers on a toss of the same coin. or-beauties won or lost bets on heads once. by contrast, and-beauties won bets on heads once if the coin landed heads but lost bets on heads twice if the coin landed tails. they therefore had more to lose by betting on heads. for each accepted bet, and-beauties earned (b – c) when the coin fell heads because the bet was placed once but lost c when the coin fell tails because the bet was placed twice. bets on heads were better than even money when (b – c) > c which is equivalent to c/b < / . if instead, and-beauties had bet on tails they would have lost c when the coin landed heads but earned (b – c) when the coin landed tails. therefore, bets on tails would be better than even money whenever (b – c) > c which is equivalent to c/b < / . thus, and-beauties employ different decision rules for bets on heads and tails. thirders interpret this difference as evidence for unequal credences of heads and tails and would interpret the right-hand sides of c/b < / and c/b < / as credences and the left-hand sides as ratios of stakes to payouts. halfers deny this interpretation. when an and-beauty bets on heads, the expected cost is c* = . c for payout b. her decision rule c/b < / can be written as c*/b < ½. when an and-beauty bet on tails, the expected cost is c* but the payout is b. her decision rule c/b < / can be written as c*/ b < ½. in the rearranged forms, the left-hand sides represent ratios of stakes to payout and the right-hand sides and-beauties’ consistent credence in heads. elga’s sleeping beauty was an and-beauty. my calculations of which bets she should accept are not new. they can be found in many analyses that use dutch books and the like to probe her ‘true’ credence in heads. what differs is the interpretation. hitchcock ( ) concluded that beauty’s credence on waking changed from one-half to one-third because she learned that she was not asleep. (does a sleeping sleeping beauty have a centered world?) my interpretation is that beauty’s credences do not change. she bets according to her beliefs but these beliefs include an understanding that the stakes depend on the unknown outcome of the coin toss. this diagnosis is not new. arntzenius ( ) concluded that beauty’s degree of belief in heads should be one-half but that she “should bet at odds that differ from her degrees of belief.” bradley and leitgeb ( ) similarly distinguished between her credences and fair betting odds. their analysis parallels my own: what is at stake depends on the toss of the coin. or-beauties and and-beauties differ not because of different beliefs about the frequency of heads but because of different beliefs about how often they must pay if the coin lands tails. neither or-beauties nor and-beauties obtain relevant new information when woken. both believe that p(heads) = ½. halfers are vindicated. and-beauties are fated to choose the same on monday and tuesday if the coin lands tails. therefore, twice as much is at stake if the coin lands tails. as a consequence, h, t and t are given equal weight when deciding whether to bet on heads. from the perspective of an observer of their behavior who cannot ask them to explain their beliefs, and-beauties behave ‘as if’ they believed p(heads) = / . their behavior can be predicted by this belief. in this limited sense, thirders are vindicated. hamilton’s wager the preceding analysis was stimulated by thinking about a problem from my doctoral thesis that concerned degrees of relatedness of triploid endosperm (a tissue within seeds). philosophers may be interested in the parallels. unfortunately some biological background is necessary. i beg my readers’ forbearance. inclusive fitness theory was developed to understand fitness trade-offs among kin (hamilton , ). one of the simplest expressions of this theory is known as hamilton’s rule. this rule-of-thumb predicts the action of natural selection when a gene’s expression confers a benefit (b) on one individual’s fitness at a cost (c) to another individual’s fitness. natural selection favors the genetic action if rbb – rcc > , where rb and rc are measures of the probabilities that the two individuals carry a copy of the gene. hamilton’s rule can be rewritten as c/b < rb/rc ( ) the left-hand side of this inequality is a ratio of the fitness consequences of the action for the two individuals affected and the right-hand side a ratio of their probabilities of carrying recent replicates of the responsible gene. strictly speaking, hamilton’s rule is not about particular individuals but about average outcomes of interactions between specified categories of kin. thus, the relatednesses can be considered to represent the relative frequencies with which a genetic lineage has experienced the costs and benefits of its own action. readers will immediately recognize ( ) as a restatement of the gambler’s decision rule. a gene can be considered to be paying a cost c for a chance of receiving a benefit b. what is uncertain is not whether one class of individuals pays c and another class receives b, but whether the gene placing the bet is present in the relevant individuals, with rc the frequency of the gene in the class of individuals who have paid the cost and rb the frequency of the gene in the class of individuals who have received the benefit. credences of rational actors are revealed by their acceptance and rejection of wagers. genes lack beliefs. but the ancestors of present-day genes have passed repeatedly through a sieve that retained variants that made ‘better’ choices and discarded those that made ‘worse’ choices. by this process, present-day genes are expected to behave ‘as if’ they were rational agents who judge the probability of current events by the past frequency of similar events. thus, the ‘credences’ of genetic agents can be inferred from implicit weightings of alternative outcomes in evolutionary games. embryos and endosperms the adjectives haploid, diploid, and triploid refer to nuclei containing one, two, or three copies of each kind of gene. plants exhibit an alternation of haploid and diploid generations. offspring may be haploid or diploid and have both haploid and diploid parents. dad and mom will be used as technical terms to refer to haploid parents and father and mother to refer to diploid parents (haig ). the haploid products of plant meiosis are called spores. mothers produce megaspores that divide to produce moms. fathers produce microspores that divide to produce dads. all nuclei of a dad or mom are genetically identical because they are derived from a single product of meiosis. moms produce eggs and polar nuclei. dads produce sperm. in most flowering plants, each dad produces two sperm and each mom produces an egg and two polar nuclei. after a process of double fertilization, one of the sperm nuclei of a dad fertilizes the egg nucleus of a mom to form a zygote that develops into a diploid embryo and the other sperm nucleus fuses with both polar nuclei of the mom to form a primary endosperm nucleus that develops into a triploid endosperm (figure ). a division of labor during seed development results in the endosperm sacrificing itself for the sake of its twin embryo. a dad and mom together produce an embryo and endosperm that have identical maternal and identical paternal genomes. the embryo possesses one copy of the paternal genome for each copy of the maternal genome but the endosperm possesses two copies of the maternal genome for each copy of the paternal genome. the situation of a gene token in endosperm that ‘does not know’ whether it is maternal (and present in two doses) or paternal (and present in one dose) is analogous to the situation of an and-beauty who is uncertain whether she bets twice because a coin landed tails or once because the coin landed heads. what credence should a gene in endosperm have about its parental origin? one- third of randomly chosen tokens from present-day endosperms were inherited from dad and two-thirds from mom. this synchronic observation suggests that endosperm genes should behave ‘as if’ they had a one-third chance of coming from dad and a two-thirds chance of coming from dad. this is a frequentist view of relatedness. a diachronic perspective suggests a different answer. any given gene token in endosperm came from mom or dad with equal likelihood. this is a bayesian view of relatedness (figure ). each token descends from a ‘parent’ token from which it received one strand of its double helix. as a token’s lineage is traced back into the past, it passes through the bodies of moms and dads in roughly equal proportions (haig ). therefore, the lineage will have been subject to natural selection half the time as a paternal token and half the time as a maternal token. tokens of successful lineages might therefore be expected to behave ‘as if’ maternal and paternal origin were equally likely. the present likelihoods, looking forward, are derived from past frequencies, looking back (haig ). the question how natural selection ‘interprets’ the double dose of maternally- derived genes in endosperm relative to the single dose of paternally-derived genes raises similar issues to those debated by halfers and thirders in the sleeping beauty problem. when an embryo inherits one dose of paternal genes from dad, its associated endosperm also inherits one dose of the same genes. should not the endosperm’s relatedness to dad be the same as the embryo’s relatedness to dad? on the other hand, an endosperm inherits a double dose of maternal genes from mom compared to an embryo which inherits a single dose. should not the greater dilution of paternal genes in endosperms (one-in-three) relative to embryos (one-in-two) mean that the endosperm is less related than the embryo to dad? three-card monte questions about the relatedness of an endosperm to its own embryo and to other embryos of the same mother arose in early attempts to apply inclusive fitness theory to seed development. westoby and rice ( ) proposed that “alleles in an endosperm are on average three times as likely to reach the next generation through the embryo with which they are associated as through some other embryo … endosperms would not therefore be selected to acquire extra provisions at the expense of other embryos as strongly as the embryos themselves would be.” queller ( ) similarly concluded that an endosperm would be less assertive in promoting the growth of the embryo in its seed relative to embryos in other seeds than would be the embryo itself. these authors believed an embryo to be less related than its associated endosperm to embryos in other seeds in the ratio one-half to two-thirds. the conclusions of these authors were soon challenged by law and cannings ( ) who found that diploidy versus triploidy made no difference to the assertiveness of endosperm in their population genetic models. this dispute can be considered an argument between endosperm-thirders and endosperm-halfers. a resolution of the disagreement was proposed by queller ( , ). sometimes thirders, sometimes halfers, got the right answer. who was right depended on details of gene expression. queller’s analysis of the endosperm problem informed my interpretation of the sleeping beauty problem. consider the relatedness r of an endosperm to its diploid mother and assume that all her embryos are half-sibs. (readers who consult the primary literature should be aware that the papers cited above consider the relatedness of an endosperm to half-sib embryos rather than diploid mothers. this involves an extra flip of a mendelian coin giving r' = / as the thirder position and r' = ¼ as the halfer position.) the relatedness of an endosperm to its mother corresponds to the probability that a gene in endosperm is of maternal origin. this is analogous to betting on tails in the sleeping beauty problem. betting on heads is analogous to the probability of paternal origin or ‘unrelatedness’ ( – r). the sleeping beauty problem will be flipped from betting on heads to betting on tails to simplify comparisons. in this conversion, the thirder contention becomes r = / , analogous to p(tails) = / , and the halfer contention remains r = ½, analogous to p(tails) = ½. consider a gene expressed in endosperm that causes a cost c to its associated embryo for a benefit b to its mother when the gene is paternally-derived (single dose), but causes a cost kc to its associated embryo for a benefit kb to its mother when the gene is maternally-derived (double dose). tokens of paternally-derived genes experience the cost c to its own embryo but do not share in the benefit to the mother whereas tokens of maternally-derived genes experience both the cost kc and the benefit kb. therefore, a gene will profit on average when kb – ( + k)c > or ( a) if the effects of the gene are dominant, ( a) simplifies to c/b < ½ because the same costs and benefits are experienced whether the gene is of maternal or paternal origin (k = ). if, on the other hand, the gene has additive effects (proportional to dosage), ( a) simplifies to c/b < / because the costs and benefits when the gene is maternally-derived will be c and b (k = ). thus, a gene expressed in endosperm with dominant effects resembles an or-beauty in the sleeping beauty problem whereas a gene with additive effects resembles an and-beauty. queller ( , ) interpreted the right-hand side of ( a) as the relatedness of endosperm to mother. therefore, he concluded that the “expression- dependent relatedness” was two-thirds for genes with additive effects and one-half for genes with dominant effects. if a gene expressed in endosperm has dominant effects, then the extra maternal dose has no consequences because a single paternal dose has the same effects as a double maternal dose. by contrast, if the gene has additive effects, then the double maternal dose has twice the influence of the single paternal dose. for this reason, a gene engaged in hamilton’s wager is expected to behave differently depending on whether it has dominant or additive effects. one of the attractive features of inequality ( ) is that it separates a ratio of phenotypic effects (c/b) on the left-hand side from a ratio of genotypic probabilities (rb/rc) on the right-hand side. inequality ( a) loses this pleasing property because a variable that scales costs and benefits (k) appears on the ‘relatedness’ rather than ‘costs and benefits’ side of the ledger. the separation of phenotypic effects from genotypic probabilities can be restored by algebraic reshuffling ( b) the left-hand side of ( b) is now a ratio of stakes (numerator) to payouts (denominator) and the right-hand side is a relatedness of endosperm to mother that is not ‘expression- dependent’. inequalities ( a) and ( b) are algebraically equivalent but ( b) provides greater conceptual clarity. if the right-hand sides of ( a) and ( b) are both interpreted as measures of relatedness then relatedness must mean different things in ( a) and ( b). if one wishes to interpret evolutionary models in terms of hamilton’s rule, then inequality ( ) must take more complex forms as models become more complex. a theoretician faces an algebraic choice of keeping the left-hand side simple and putting the extra complexity into ‘relatedness’ or keeping the right-hand side simple and putting the extra complexity into ‘costs and benefits’. queller’s ( ) inclusion of factors weighting phenotypic effects into an ‘expression-dependent relatedness’ is analogous to thirders’ inclusion of factors weighting stakes and payoffs into the credence of heads in the sleeping beauty problem. queller preserved the simplicity of ‘costs and benefits’ at the expense of making ‘relatedness’ depend on details of gene action. the status of hamilton’s rule has recently become a subject of intense dispute within evolutionary biology with passionate critics and defenders (allen et al. ; liao et al. ). models of the evolution of social interactions are inherently complex. the competing models, if well-formed, should yield similar predictions regardless of their conceptual framework, albeit in different algebraic form. i suspect that much of the heat of this debate arises from alternative algebraic parsings of equations into multivariable ‘chunks’ that are identified with intuitive concepts such as ‘relatedness’, ‘cost’, and ‘benefit’. how to parse an equation is often a question of aesthetic preference with alternative arrangements implicitly defining intuitive concepts in subtlely different ways. identity by descent and identity by ascent in the original sleeping beauty problem, there was one beauty and one coin toss that either fell heads or tails. the toss of a coin was a randomizing device that rendered outcomes uncertain. in the endosperm problem, every endosperm simultaneously contains maternal and paternal gene tokens but each solipsistic token has its own centered world if tokens do not interact. uncertainty about a token’s maternal or paternal origin arises not from randomization but from ignorance. inclusive fitness theory traditionally assumed that the unpredictable flip of a meiotic coin and ignorance of parental origin were equivalent sources of doubt in determining relatedness. consider the relatedness of embryos to their mothers. if one repeatedly sampled gene tokens from current-day mothers and asked whether identical-by-descent (ibd) tokens were present in particular embryos, then the proportion of trials in which the answer was yes would converge on one-half. this can be considered the synchronic view of relatedness. a diachronic view is useful for understanding the action of past natural selection. as a gene token’s lineage is followed back into the past, it passes through bodies of mothers and fathers in roughly equal proportions and is repeatedly present in the germline of mothers interacting with embryos. for each particular embryo, whether ibd tokens were inherited from the mother by the embryo was determined by a flip of a meiotic coin. as the number of coin flips increases, the frequency with which embryos inherited ibd tokens from their mothers should converge on one-half. thus, from both the synchronic and diachronic views, randomly selected gene tokens from mothers have probability one-half of ibd tokens in embryos. for these reasons, the relatedness of embryos to mothers is considered one-half. now consider the relatedness of mothers to embryos. from the synchronic perspective, half the gene tokens of current-day embryos have identical-by-ascent (iba) tokens in their mothers. from the diachronic perspective, a token’s ancestral lineage will have repeatedly been present in the germline of embryos interacting with their mothers. on average, the embryonic token will have been inherited from the mother in half these interactions. therefore, as the number of such interactions increases, the frequency with which embryonic tokens interact with iba tokens in mothers converges on one-half. from both perspectives, randomly-selected gene tokens from embryos have probability one-half of iba tokens in their mothers. for these reasons, the relatedness of mothers to their embryos has been considered one-half. despite the apparent symmetry of the relatedness of embryos to mothers and mothers to embryos, ibd and iba coefficients of relatedness reflect different sources of uncertainty. the probability of one-half that a maternal gene has ibd tokens in an embryo reflects uncertainty about a flip of a mendelian coin. a mother possesses two alleles at each locus, one inherited from her mother and one inherited from her father, but only one is transmitted to any particular embryo via the randomizing process of meiosis. by contrast, the probability of one-half that an embryonic gene has iba tokens in its mother reflects ignorance of parental origin. a randomly chosen gene in an embryo is equally likely to have been inherited from the embryo’s mother or father because the embryo receives one gene copy from each. a general assumption has been that parental origin makes no difference to a gene’s effects. each gene’s lineage passes repeatedly through male and female bodies while its dna sequence remains unchanged. therefore, natural selection should act on genes according to their effects averaged across maternal and paternal transmission and genes should behave ‘as if’ their parental origin is uncertain. however, if genes were to acquire an erasable ‘imprint’ on passing through male bodies that was reset after passing through female bodies, then the one-half probability that an embryonic gene had iba tokens in its mother would collapse into a probability of one for genes of maternal origin and zero for genes of paternal origin (haig , ). this would be equivalent to letting beauty know the outcome of the coin toss before placing her bets. some genes, including genes expressed in endosperm, possess locative memories of their parental origin (haig and westoby ). by processes of natural selection, these imprinted genes should conditionalize their phenotypic effects on parental origin (haig ). these findings have fundamental consequences for how coefficients of relatedness should be calculated in inclusive fitness theory. organisms no longer possess unified genomes maximizing a unitary fitness but contain maternal and paternal factions with competing agendas (haig , , ). conclusions beauty’s paired wakings on tails and the double dose of genes from mom in endosperm are conceptually similar. the second waking or second dose is a mere doubling of a single draw from the distribution of a random variable. they are duplicate probability. it should be evident that doubling, tripling, or quadrupling the outcome of a single draw does not affect the expected value of the next independent draw of the random variable nor does it change the value of the single draw that has already been made. the probability that a gene came from a mother or father in the previous generation is one- half as is the probability that a toss of a fair coin is heads no matter how many times the outcomes are repeated. my analysis has hinged on the conjunctions and and or. this pivot appeared in the difference between living in a world in which one expects a and b while living at temporal locations where one experiences a or b. distinct events that share the same worldly probability are mutually exclusive in locative space. the pivot reappeared in thinking about wagers on duplicate experiences. beauty’s choices changed when she paid for bets in a and b rather than a or b. the unrecognized conjunction of these two problems of conjunction, and the failure to disentangle them, may partly explain why the sleeping beauty problem has been so intractible. references allen b, nowak ma, wilson eo ( ) limitations of inclusive fitness. proc natl acad sci usa : – . bradley d, leitgeb h. ( ) when betting odds and credences come apart: more worries for dutch book arguments. analysis : – . arntzenius f ( ) reflections on sleeping beauty. analysis : – . bostrom n ( ) sleeping beauty and self-location: a hybrid model. synthese : – . briggs r ( ) putting a value on beauty. oxf stud epistem : – . elga a ( ) self-locating belief and the sleeping beauty problem. analysis : – . haig d ( ) parental antagonism, relatedness asymmetries, and genomic imprinting. proc r soc b : – . haig d ( ) genomic imprinting, sex-biased dispersal, and social behavior. ann ny acad sci : - . haig d ( ) intragenomic politics. cytogenet genome res : – . haig d ( ) the strategic gene. biol philos : – haig d ( ) filial mistletoes: the functional morphology of moss sporophytes. ann bot : – . haig d ( ) fighting the good cause: meaning, purpose, difference, and choice. biol philos : – . haig d, westoby m ( ) parent-specific gene expression and the triploid endosperm. am nat : – . hitchcock c ( ) beauty and the bets. synthese : – . law r, cannings c ( ) genetic analysis of conflicts arising during development of seeds in the angiospermophyta. proc r soc b : – . lewis d ( ) attitudes de dicto and de re. phil rev : – . lewis d ( ) sleeping beauty: reply to elga. analysis : – . liao x, rong s, queller dc ( ) relatedness, conflict, and the evolution of eusociality. plos biol :e . meacham cjg ( ) sleeping beauty and the dynamics of de se beliefs. philos studies : – . queller dc ( ) kin selection and conflict in seed maturation. j theor biol : – . queller dc ( ) models of kin selection on seed provisioning. heredity : – . queller dc ( ) inclusive fitness in a nutshell. oxford surv evol biol : – . westoby m, rice b ( ) evolution of the seed plants and inclusive fitness of plant tissues. evolution : – . figure : a haploid female gametophyte (mom) contributes an egg nucleus to the embryo within a seed and two polar nuclei to the endosperm. these contributions are represented by filled circles. a haploid male gametophyte (dad) contributes a sperm nucleus to both the embryo and the endosperm. these contributions are represented by unfilled circles. what is the ‘probability’ that a gene in the endosperm comes from dad? from the perspective of an external observer, one-third of the gene tokens in endosperm come from dad, suggesting an answer of one-third. from the perspective of a gene token in endosperm looking backward, it either came from dad or from mom, suggesting an answer of one-half. sleeping beauty in a grain of rice eternal beauty ephemeral beauty beauty at rest gambling with beauty hamilton’s wager embryos and endosperms three-card monte identity by descent and identity by ascent conclusions references research article biology, engineering and medicine biol eng med, doi: . /bem. volume : - issn: - a modified sleeping beauty transposon vector system integrates and settles genes in the genome kazuyoshi kaminaka * and chikateru nozaki research and development division, kikuchi research center, km biologics co., ltd., - kyokushi kawabe, kikuchi-city, kumamoto - , japan department of medical technology, kumamoto health science university, izumi-machi, kita-ku, kumamoto-city, kumamoto - , japan abstract sleeping beauty (sb) exhibits efficient cut-and-paste transposition in a wide range of mammalian cells. using this characteristic, a new vector system (the sb system) was previously developed for integration of target genes into the host genome and is now used as a research tool and for gene therapy. however, there are concerns about the retransposition and the size restriction to be integrated into this system. to overcome these issues, we constructed a modified transposon vector system with lox sequences and estimated its transposable activity and cre/lox recombination ability in hela cells. we also estimated the possibility of the retransposition by plasmids with defective inverted repeat/direct repeat structures presumed to be taken after cre/lox recombination. we demonstrated that our modified transposon vector system could efficiently cause recombination mediated by the cre/lox system following the transposition of the target genes into the genome and eliminate the possibility of retransposition of the genes. we believe our modified transposon vector system could be used not only as a research tool but also as a safer and more versatile gene integration system in the medical field. *correspondence to: kazuyoshi kaminaka, development department, research and development division, kikuchi research center, km biologics co., ltd., - kyokushi kawabe, kikuchi-city, kumamoto - , japan, tel: + - - - ; fax: + - - - ; e-mail: kaminaka@kmbiologics.com key words: sleeping beauty, transposon, retransposition, cre/lox recombination, inverted repeat/direct repeat structures, gene integration received: july , ; accepted: july , ; published: july , introduction gene integration technology has become essential for the production of recombinant proteins and organisms, as well as gene therapy application [ - ]. the most critical point of this technology is to integrate target genes into the host genome safely while yielding high integration frequency. sleeping beauty (sb) is a transposon belonging to the tc /mariner superfamily, which was reconstructed from transposon fossils found in fish genomes and exhibited efficient cut-and-paste transposition in mammalian cells [ ]. these peculiar characteristics were exploited by researchers to develop a new vector system (the sb system) for the integration of target genes into the host genome. the system encompasses two plasmids: one expresses a transposase gene, which encodes an enzyme to carry the transposable activity, and the other is a transposon vector (the sb vector) having inverted repeat (ir) sequences with two direct repeats (dr) sequences (termed ir/dr) at both ends. the gene of interest is placed between the ir/drs. this system has a broad spectrum and high integration efficiency in mammalian cells [ ]. in addition, the possibility of retransposition of the target genes can be reduced by segregating the transposase expression cassette from the transposon. although the sb system is useful for the integration of target genes, several issues exist. first, there is a possibility that the target genes integrated by the sb system can be retransposed to another site in the genome. because the transposon vector utilizes the transposable activity on the genome that triggered its discovery, the target genes integrated by the transposon vector must be transposition competent on the genome. in the sb system, the possibility of retransposition is minimized using a two-component plasmid system. however, the target genes between both ir/drs in a transposon vector (transposable substrate dna) can readily retranspose to another site when a transposase is supplied [ , ]. additionally, a few reports have demonstrated that the occasional, unintended retransposition occurred in fish genomes [ , ]. second, the target gene size integrated by the sb system is limited. the transposition efficacy of the sb system decreases as the size of the target gene increases. the efficiency decreased to % of the original transposon size when the transposon exceeds kbp in size [ ]. in general, the addition of a promoter and a polya addition signal sequences are required for gene expression within the host, further limiting the size of the target gene to be loaded in the sb vector. moreover, to select hosts with integrated target genes effectively based on drug resistance, the expression cassette of a drug-resistance gene is also introduced into the vector, additionally shortening the size of the target genes to be introduced. thus, genes with a large size [ , ] or those requiring the expression of multiple components [ ] would not be suitable for integration using this system. in this study, to overcome these issues with the sb system, we constructed a modified transposon vector system with lox sequences that prevented retransposition and enabled insertion of genes without size limitations by cre/lox recombination. results transposition activity of the modified transposon vector a modified transposon vector containing the lox sequence may allow us to overcome issues in the sb system by using cre/lox recombination. izsvák et al. ( ) [ ] showed that disrupting the mailto:kaminaka@kmbiologics.com kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - our modified vectors, ir/dr-puro/ ’lxp, ir/dr-puro/lxpadb and a positive control vector ir/dr-puro (sb vector) were constructed from a basal plasmid ir/dr-nta-ad, which had ir/drs at both ends (figure a). ir/dr-puro (sb vector) had the same ir/drs elements previously reported by ivics, hackett, plasterk, and izszák ( ) [ ]. the modified transposon vector ir/dr-puro/ ’lxp had the lox sequence, which is a left element mutant of loxp [ ], between two dr sequences in the ′-ir/dr. another modified transposon vector, ir/ ir/dr structure, e.g., by deletion or mutation, leads to a significant reduction in transposition activity. as shown in figure , in the modified transposon vector with lox sequences between two dr sequences in the ir/drs, the ir/dr structure was disrupted, and its transposable activity seemed to disappear by cre/lox recombination. based on this idea, we constructed modified transposon vectors with lox sequence(s) between two dr sequences present in the ir/drs (figure ). figure . modified transposon vector system. in the modified transposon vector system, the modified transposon vector with lox sequence(s) in the ir/dr(s) is used instead of the sb vector. the target gene and/or a marker gene are first introduced into the genome of the host by the transposition, similar to the sb system. excision of the marker gene (a), exchange with another gene (b), and insertion of another gene (c) can be performed by cre/lox recombination after integration into the genome by the transposition figure . constructed transposon vectors. (a) a basal plasmid ir/dr-nta-ad for the transposon vector construction. the plasmid was repaired from a transposon in the salmon genome and constructed, as shown in the experimental procedures. the nucleotide sequences of the transposable element in the plasmid were also shown. (b) transposon vectors investigated in this study. sb vector (ir/dr-puro) was constructed as a positive control. the modified transposon vector ir/dr-puro/ ’lxp had a mutant lox sequence (lox ) between two dr sequences in the ′-ir/dr. another vector, ir/dr-puro/lxpadb, had the same ′-ir/dr with ir/dr-puro/ ’lxp and the loxp and polya addition signal sequences between two dr sequences in the ′-ir/dr. all three vectors had puro between both ir/drs as a marker gene kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - dr-puro/lxpadb, had the lox sequence in the ′-ir/dr and the loxp sequence flanked with the polya addition signal sequence derived from bovine growth hormone in the ′-ir/dr. on ir/dr-puro/lxpadb, we specifically chose the lox and loxp combination to generate the three expected types of cre/lox recombination shown in figure . after cotransfection of ir/dr-puro (positive control sb vector) with the transposase expression plasmid pcaggs/sb into hela cells, puromycin-resistant hela cell clones (hela/puro) were obtained . times more frequently than those obtained from transfection with the vector alone (csb/cn index of . ). in contrast, the modified transposon vectors ir/dr-puro/ ’lxp and ir/dr-puro/lxpadb had csb/cn indexes of . and . , respectively (table ). this result indicated that our modified transposon vectors retained transposable activity like as the sb vector, even though the lox sequences and polya addition signal sequence were inserted between two dr sequences. gene replacement by the cre/lox system after transposition of the transposon vector in order to confirm that our modified transposon vectors also retained the recombination ability mediated by the cre/lox system after transposition into the genome, the donor plasmid plx/gfp/neo/ pa(-) was introduced with pcaggs/cre into hela/puro, which was obtained from the transposition of ir/dr-puro/lxpadb, to replace the puromycin-resistance gene expression cassette (puro) in the genome with the neomycin-resistance gene and the green fluorescent gene expression cassettes (neo and gfp). the genomic dnas from three hela cell clones sensitive to puromycin, resistant to neomycin, and emitting green fluorescence (hela/neo) were analyzed by southern blotting (figure ). if hela/neo acquired neo and gfp by transposition of ir/dr- puro/lxpadb followed by cre/lox recombination with plx/gfp/neo/ pa(-), a . -kbp fragment would be detected from the genomic dna digested with aflii by a neo-derived probe, and no dna fragment would be detected using a puro-derived probe (figure a). instead, a . -kbp fragment would be detected using a puro-derived probe when the random integration of plx/gfp/neo/pa(-) occurred (figure a). as shown in figure b, clone nos. and were considered to be obtained by the transposition of ir/dr-puro/lxpadb followed by cre/ lox recombination with plx/gfp/neo/pa(-) since a . -kbp fragment was detected using the neo-derived probe. in clone no. , a fragment over . kbp was detected by the neo-derived probe. this clone was considered not to be obtained by gene replacement but as a result of insertion of plx/gfp/neo/pa(-) at the lox site and subsequent excision of dna between loxp sequences in the ′-ir/dr of ir/dr- puro/lxpadb and at the ′-end of plx/gfp/neo/pa(-) by cre/lox recombination. in order to further confirm that hela/neo was obtained by transposition and subsequent gene replacement, we also analyzed both terminal regions of the inserted gene in clone no. using a genome walking method. as shown in figure a, the lox sequence in the ′ region was exchanged for the double mutant lox sequence (mutant construct lox sequences pcaggs/sb (transposase) colonies csb/cn ’-ir/dr ’-ir/dr ir/dr-puro (sb vector) no (cn) . yes (csb) ir/dr-puro/ ’lxp no (cn) . yes (csb) ir/dr-puro/lxpadb no (cn) . yes (csb) table . transposition activity of transposon vectors kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - figure . gene exchange in hela cells. (a) schematic structure of integrated genes in the genome of hela/puro and hela/neo cells and the donor plasmid plx/gfp/neo/pa(-). (b) southern blotting analysis of aflii-digested genomic dnas of hela/neo clones. hela/puro: aflii-digested genomic dna of the clone before cre/lox-mediated gene exchange was performed; cre(-): aflii-digested genomic dna of the clone obtained by transfection of plx/gfp/neo/pa(-) without pcaggs/cre; ir/dr-puro/lxpadb: the modified transposon vector introduced to obtain hela/puro cells sequences of lox and lox ), and the loxp sequence in the ′ region remained. furthermore, due to gene replacement, the inner two dr sequences in the four drs of the transposon vector were removed, and the region between the ′ and ′ lox sequences was the same as the sequence of the donor plasmid plx/gfp/neo/pa(-). the region outside of the lox sequences was the same as the sequence of ir/dr- puro/lxpadb (figure a). besides, the region outside of both ends of ir/dr-puro/lxpadb (ta dinucleotide) matched with the sequence of human chromosome by a search in the genebank database (figure b). from these results, we concluded that our modified transposon vector was able to efficiently insert the target genes into the genome based on transposable activity and to cause the subsequent recombination mediated by cre/lox recombination. transposable activity after cre/lox recombination of the integrated transposon vector as described above, the modified transposon vector was capable of recombination by the cre/lox system after transposition into the genome. next, in order to confirm that the gene integrated into the genome could not retranspose after recombination by the cre/lox system (figure ), we constructed two types of plasmids with possible terminal structures mimicking those after the cre/lox recombination (figure ) and compared their transposable activities with ir/dr-puro/ lxpadb. one (ir/dr- ’ir/puro) was the deleted construct of the inner dr sequence in the ′-ir/dr, which would be formed after the excision between loxps existing inside and outside of the ir/dr by cre/ lox recombination (figure a). another ( ’+ ’ir/puro) was the deleted construct of the two inner dr sequences in the ′- and ′-ir/dr, which would be formed after gene replacement at lox sequences in the ′- and ′-ir/dr (figure b). ir/dr- ’ir/puro, in which only an inner dr sequence in the ′-ir/ dr had been removed, had no transposable activity, similar to ’+ ’ir/ puro, in which both of the inner dr sequences had been removed (table ). from this result, we concluded that the target genes could be integrated into the genome with no retransposition by utilizing the cre/ lox system following the transposition of our modified vectors. discussion by inserting a lox sequence between two dr sequences present in the ir/dr of the sb vector, we believed that we could excise the inner dr in the ir/dr and eliminate transposable activity via cre/ lox recombination. however, in a previous study, it was found that mutating several sequences or changing the distance between the two dr sequences in the ir/dr could cause a significant reduction in transposition efficiency [ ]. therefore, to overcome these contradictory problems, we decided to not change the distance (number of bases) between the two dr sequences in the ir/dr and to avoid kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - figure . sequences at lox sites and outsides the transposon. (a) sequence at the lox site of the genome or plasmids at each step of the gene exchange. underlining shows lox sequences, and italic letters indicate the mutated site of the left element in lox and the right element in lox . (b) the sequence outside of the transposon. the sequences of both ends and outside of the modified transposon vector ir/dr-puro/lxpadb are indicated by black letters, and the sequences outside of the integrated gene in hela/neo cells are indicated by light blue lower-case letters. the underlined dinucleotide ta indicates the transposition target sites figure . plasmids with defective irs/drs. ir/dr-puro/lxpadb was the modified transposon vector with the native ir/dr and was used as a positive control. ir/dr- ’ir/puro is a plasmid with a defective ′-ir/dr, in which the inner dr was excised, and with the native ′-ir/dr. ’+ ’ir/puro is a plasmid with defective ir/drs, in which the inner drs were excised the hotspot ( ′-half sequences of dr) when inserting the lox sequences between two dr sequences in the ir/dr of the sb vector. as a result, our modified transposon vectors were able to efficiently introduce a gene into the genome via a plasmid vector, similar to the sb system. in addition, plasmids having a defective ir/dr structure predicted by cre/ lox recombination after integration into the genome with our modified transposon vector could not transpose, even when a transposase was supplied. therefore, we demonstrated that our modified transposon vectors could efficiently introduce the target genes into the genome and settle these genes. in addition to gene replacement and excision, our modified transposon vector system could be utilized for cre/lox recombination, a gene insertion reaction, to eliminate the possibility of retransposition. when this reaction occurred at the lox site present between two dr sequences in the ir/dr, the distance between the two drs changed, resulting in structural changes in the ir/dr. this change could be easily applied to lose transposable activity, as previously demonstrated [ ]. a transposon vector with additional loxp sequences between the two drs in the ′-ir/dr had no transposable activity (data not shown). in this study, the efficiency of cre/lox recombination after the introduction of our modified transposon vector into the genome was not clarified. however, because we could easily select gene-replaced clones by the expression of marker genes (neo and gfp), we assumed this could not affect cre/lox recombination, even if a lox sequence exists within the ir/dr. furthermore, we chose the combination of lox and loxp combination in ir/dr-puro/lxpadb as we expected kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - the three types of cre/lox recombination that are shown in figure . when one expects more effective gene replacement after transposition, the combination of lox and lox can be used instead of that of lox and loxp [ ]. however, the lox sequence inserted in the modified transposon vector could be modified accordingly to the expected cre/ lox recombination. it is challenging to introduce genes larger than kbp efficiently using the sb system [ ]. the replaced gene after transposition of our modified transposon vector system was about . kbp in size. therefore, we did not show that our vector system could introduce genes over kbp in size in this study. however, gene replacement by the cre/lox system can substitute genes of over kbp [ ] efficiently, and dna up to kbp can be inserted into the genome in plants using this system [ ]. therefore, we expect that genes can be efficiently introduced into the genome using our modified transposon vector system and the cre/ lox system, without size limitations. to overcome the size restriction to be transposed in the sb system, a next-generation transposon system was previously developed [ ]. this system combined a hyperactive sb transposase with a transposon vector having two complete pairs of ir/drs in inverted orientations (sandwich configuration). consequently, their new transposon system could load genes over kbp while maintaining relatively efficient transposition. despite this improvement in the sb system, our modification of the sb vector shown in this study is useful because it could also be applied to their new transposon system and could eliminate retransposition after transposition into the genome. the sb system containing our modified transposon vector system utilized transposons belonging to the tc /mariner superfamily. transposons in this superfamily are less likely to be inserted into and disrupt functional genes compared with other transposons or viral vectors [ - ]. however, once a transposase is supplied, although it may not have a high incidence rate, transposition would occur at a probability of . × − events per cell generation in the genome [ ]. furthermore, even if the probability is low, transpositions may be caused by invasion from other active transposons [ ]. these possibilities may limit the application of the sb system in gene therapy owing to increased risk of oncogenesis [ , ]. to safely carry out gene integration into the genome with our modified transposon vector, multiple insertions of modified transposon vectors must also be avoided because the region between those vectors might be deleted by cre/lox recombination events, especially when multiple vectors are inserted into the same chromosome. under our experimental condition, we predicted that our modified transposon vectors would be inserted into multiple genomic loci. according to a previous report [ ], a single insertion event could be ensured at the “low” transposon dosage condition in the sb system. therefore, by optimizing the “low” transposon dosage condition for our modified transposon vector, we consider that the insertion of a single copy of the transposon into the genome could be achieved. in summary, our modified transposon vector system eliminated concerns regarding potential retransposition after the efficient introduction of genes into the genome. by studying optimal conditions construct pcaggs/sb (transposase) colonies csb/cn ir/dr-puro/lxpadb (all four drs conserved) no (cn) . yes (csb) ir/dr- ’ir/puro (no inner dr in ’-ir/dr) no (cn) . (< ) yes (csb) ’+ ’ir/puro (no inner drs in both ir/drs) no (cn) . (< ) yes (csb) table . transposition activity of plasmids with defective ir/dr kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - for a single copy insertion and in vivo application, we believe that our modified transposon vector system could be used not only as a research tool but also as a safer and more versatile gene integration system in the medical field. experimental procedures restriction enzymes, genes, and primers unless otherwise stated, restriction enzymes were purchased from takara bio (shiga, japan). the neomycin-resistance gene in pmc neo (agilent, ca, usa) and the green fluorescent gene in pegfp-n (bd biosciences, nj, usa) were used for the construction. puro in ppgkpuro kindly provided by dr. watanabe (naro) was also used. furthermore, the cre recombinase expression plasmid (pcaggs/cre) and the lox sequences loxp, lox , and lox were kindly provided by dr. araki (kumamoto university). primers used for the construction of vectors or plasmids were synthesized at eurofins genomics (tokyo, japan) and are listed in table . construction of plasmids sb system the two components of the sb system, a transposase expression plasmid that carries transposable activity and an sb vector that becomes the substrate dna of the transposition, were constructed as follows. polymerase chain reaction (pcr) was performed with primers tce/in and tce/st based on the sequences of genbank accession nos. l and l , respectively, and with salmon sperm dna (nippon gene, tokyo, japan) as a template. an amplified dna fragment of about kbp, which encoded the transposase gene, was repaired to the same amino acid sequence as the transposase in the sb system by site-directed mutagenesis according to the method reported by ivics, hackett, plasterk, and izszák ( ) [ ]. subsequently, the repaired transposase gene was inserted downstream of the chicken β-actin promoter of the expression plasmid pcaggs [ ], resulting in the transposase expression plasmid pcaggs/sb. in order to construct an sb vector as a substrate for the transposase, first, a transposon of approximately . kbp with ir/drs at the ′- and ′-ends was amplified by pcr with a primer tc [ ] and salmon sperm dna (nippon gene) as a template. next, the sequences of the isolated ir/drs were repaired to those of genbank accession no. l [ ], using their site-directed mutagenesis method. then, unique restriction enzyme recognition sites (noti and sali) were introduced between the ir/drs of the repaired transposon (ir/dr-nta-ad, figure a). transposon vectors the transposon vectors we investigated in this study were constructed as below. the sb vector ir/dr-puro was constructed as positive control by inserting puro into the sali site of ir/dr-nta-ad, which had the same ir/drs as the sb vector (figure b). the modified transposon vector ir/dr-puro/ ’lxp was constructed as follows. first, pcr was performed using ir/dr-nta-ad as a template and primers sp and ps/lx r to amplify a dna fragment of about bp in which the lox sequence was inserted between two drs in the ’-ir/dr. after digestion of the fragment with pshai and xhoi, the fragment was swapped with a fragment of ir/dr-nta-ad digested with the same enzymes, yielding the transposon vector ir/dr- ad/ ’lxp having the lox sequence. subsequently, puro was inserted into the sali site of this vector to construct ir/dr-puro/ ’lxp (figure b). another modified transposon vector ir/dr-puro/lxpadb was constructed as follows. first, the ′-ir/dr fragment from ir/dr-nta- ad digested with sali and bglii was subcloned into psp (promega, wi, usa), resulting in ′ir/dr-ad. next, a dna fragment amplified by pcr using this ′ir/dr-ad as a template and primers sp and af/lxpar was digested with aflii and sali and swapped with the fragment of ′ir/dr-ad digested with the same restriction enzymes. this resulting plasmid ′ir/dr-lxpa had a loxp sequence flanked with a polya addition signal sequence between two drs in the ′-ir/dr. subsequently, the ′ir/dr-lxpa was digested with bglii and sali and swapped with the dna fragment of ir/dr-ad/ ’lxp digested with the same restriction enzymes. the resulting plasmid ir/dr-ad/lxpadb had a lox sequence in the ′-ir/dr and a loxp flanked with a polya addition signal sequence in the ′-ir/dr. puro was inserted into the sali site of this plasmid to construct ir/dr-puro/lxpadb (figure b). plasmid for gene replacement by the cre/lox system in the cre/lox system, gene excision, insertion, and replacement reactions can occur. in order to confirm the cre/lox recombination reaction after transposition of the modified transposon vectors into the genome, we constructed a plasmid for gene replacement (a donor plasmid) having a mutant lox sequence and neo without a polya addition signal sequence to efficiently induce the replacement reaction [ ]. primer sequence sequence origin tce/in atgggaaaat caaaagaaat cagccaaga genbank accession. no. l tce/st ttagtatttg gtagcattgc ctttaaat genbank accession. no. l tc tacagttgaa gtgtaagttt a a.d. radice et al., sp atttaggtga cactatagaa c sp promoter ps/lx r atgacttgtg tcataacttc gtataatgta tgctatacga acggtaaact attgtttgtt aacaagaaat psha i site + lox af/lxpar cctgtcttaa gatttcctca ttttattata acttcgtata atgtatgcta tacgaagtta tagtagagag aatgattcat ttcagc aflii site + bovine growth hormone-derived poly a addition signal + loxp lx /lxp-f tccgctcgag ataacttcgt atagcataca ttatacgaac ggtacgaatt caggcctgtc gacggatcct xhoi site + lox + ecori and stui sites lx /lxp-r tccagatcta taacttggta taatgtatgc tatacgaagt tatggccagg atccgtcgac aggcctgaat tc bglii site + loxp + msci, stui, and ecori sites ap gtaatacgac tcactatagg gc adaptor in bd genomewalker universal kit ap actatagggc acgcgtggt adaptor in bd genomewalker universal kit cag/gsp gcatatgata cacttgatgt actgcca promoter in pcaggs cag/gsp gcgggccatt taccgtaagt tatgta promoter in pcaggs neo/ f gcgatgcctg cttgccgaat atcat neomycin resistance gene in pmc neo neo/ f cgctatcagg acatagcgtt ggcta neomycin resistance gene in pmc neo table . primers used for vector construction kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - after mixing lx /lxp-f and lx /lxp-r with a complementary sequence of bases at the ′-ends, a dna fragment consisting of lox and loxp sequences was amplified by pcr with no template dna and primers and then cloned into the xhoi and bglii sites of psp (lx /lxp/psp). next, after ecori- and msci-mediated digestion (new england biolabs, ma, usa) of the plasmid, gfp with the promoter derived from pcaggs was inserted at these sites between the lox and loxp sequences. furthermore, downstream of gfp, neo derived from pmc neo was inserted as a marker gene, resulting in a donor plasmid plx/gfp/neo/pa (-) with lox and loxp sequences at both ends (figure a). estimation of transposable activity in hela cells the transposable activities of the constructed transposon vectors (figure ) were evaluated according to the method reported by izsvák et al. ( ) [ ] in human cervical cancer-derived hela cells (sumitomo dainippon pharma, tokyo, japan). briefly, hela cells seeded into -well plates ( × cells/ ml/well) the day before were transfected with the complex of trans-it lt (takara bio) and the dna mixture of pcaggs/ sb and one of the constructed transposon vectors ( . μg each), according to the manufacturer’s protocol. simultaneously, cells transfected with the complex with each of the constructed transposon vectors alone were prepared. two days after the transfection, the cells were passaged into -cm dishes and cultured in dulbecco’s modified eagle medium (sigma-aldrich, mo, usa) supplemented with % fetal bovine serum (hyclone, ut, usa) and μg/ml puromycin for approximately weeks. cells were then stained with % methanol (wako pure chemical, osaka, japan) containing . % crystal violet (kishida chemical, osaka, japan). all procedures were performed duplicate for each transposon vector, and the transposable activity of each vector was estimated by the csb/cn ratio, where csb indicates the mean colony number obtained by cotransfection of pcaggs/sb and each transposon vector, and cn indicates the mean number obtained by the transfection of each transposon vector alone. gene replacement by the cre/lox system puro in hela/puro obtained by the transposition of ir/dr-puro/ lxpadb was replaced as follows. hela/puro cells seeded into -well plates ( × cells//well) the day before were transfected with the complex of trans-it lt and the dna mixture of pcaggs/cre and plx/gfp/neo/pa(-) ( . μg each) and then cultured in dulbecco’s modified eagle medium supplemented % fetal bovine serum. after days, the cells were passaged into -cm dishes and cultured for approximately weeks in the presence of μg/ml g (takara bio). subsequently, clones emitting green fluorescence and showing puromycin sensitivity (hela/neo cells) were selected. genome analysis in hela/puro and hela/neo cells genomic dnas in hela/puro and hela/neo cells ( – × cells each) were prepared according to a previously described method [ ], and their concentrations were determined by measuring the absorbance at nm. southern blotting analysis was performed as follows. briefly, genomic dnas ( μg each) and plasmids (ir/dr-puro/lxpadb and plx/gfp/neo/pa (-), ng each) were digested with aflii and separated by electrophoresis on . % agarose gels (bio-rad, ca, usa). after separation, dnas were transferred to nylon filters (hybond-n+; ge healthcare japan, tokyo, japan) by alkaline transfer. the dna fragment with puro or neo was detected using probe dna prepared from puro or neo and labelled with [α p] dctp (perkinelmer, ma, usa). in order to confirm that the integrated genes in hela/neo cells were transposed and subsequently replaced from puro, both terminal regions of the integrated genes were analyzed by the genome walking method. briefly, the genomic dna from hela/neo cells was digested independently with restriction enzymes ecorv, pvuii, sspi, and naei, and an adaptor attached to a bd genomewalker universal kit (takara bio) was ligated. the resulting libraries were amplified by nested pcr with the primer combination of ap and cag/gsp followed by ap and cag/gsp for analysis of the ′ terminal region. nested pcr was also performed with the primer combination of ap and neo/ f followed by ap and neo/ f for analysis of the ′ terminal region. the amplified dna fragments were cloned into plasmid pcr . using a topo ta cloning kit (thermo fisher scientific, ma, usa), and the nucleotide sequences were analyzed. furthermore, the sequence data were compared with data from the genebank database in ncbi to identify the integrated site of the gene in the genome. estimation of transposable activity after cre/lox recombination instead of estimating the transposable activity of the gene after cre/lox recombination following the transposition from the modified transposon vector to the genome, we constructed and estimated plasmids having defective ir/dr structures predicted after cre/lox recombination as follows. hela/puro/sg cells obtained by transfection of ir/dr-puro/ lxpadb without pcaggs/sb were transfected with pcaggs/cre and plx/gfp/neo/pa(-), and hela/neo/sg cells were then selected as the same manner described above. the hela/neo/sg cells were expected to have the sequences of ir/dr-puro/lxpadb in the ′ and ′ ends and those of plx/gfp/neo/pa(-) between lox sequences. the genomic dna of hela/neo/sg cells was subjected to genome walking to obtain dna fragments with defective ′- or ′-ir/dr structures. using these fragments, a plasmid (ir/dr- ’ir/psp) in which only the ′-ir/dr was defective and a plasmid ( ’+ ’ir/psp) in which both the ′- and ′-ir/ drs were defective were constructed. furthermore, puro was inserted into the sali site of these plasmids, resulting in ir/dr- ’ir/puro and ’+ ’ir/puro, respectively. ir/dr- ’ir/puro with the defective ′-ir/dr structure, ’+ ’ir/ puro with both defective ir/dr structures, and ir/dr-puro/lxpadb with the complete ir/drs (figure ) were evaluated to estimate their transposable activities as described above. sequence analysis nucleotide sequences of dna fragments amplified by pcr during construction, clones obtained by the genome walking method, and constructed plasmids were determined using a big dye terminator cycle sequencing fs ready reaction kit and abi prism genetic analyzer (thermo fisher scientific). acknowledgements this work was supported by km biologics; potential conflict of interest is managed by km biologics. we are grateful to dr. m. araki for providing us with pcaggs/cre and lox sequences and for helpful advice regarding the cre/lox system. we also thank dr. s. watanabe for providing us with ppgkpuro and ms. r. kawamura for her experimental assistance in this study. kaminaka k ( ) a modified sleeping beauty transposon vector system integrates and settles genes in the genome biol eng med, doi: . /bem. volume : - copyright: © kaminaka k. this is an open-access article distributed under the terms of the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. references . pettit dk, rogers rs, arthur k, brodsky y, clark rh, et al. 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( rd ed.). cold spring harbor laboratory press, cold spring habor, new york. https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pmc/articles/pmc / https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pmc/articles/pmc / https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ https://www.ncbi.nlm.nih.gov/pubmed/ title correspondence abstract key words introduction results discussion experimental procedures acknowledgements references city, university of london institutional repository citation: seago, k. ( ). aspects of gender in translations of "sleeping beauty". comparative critical studies, ( ), pp. - . this is the unspecified version of the paper. this version of the publication may differ from the final published version. permanent repository link: http://openaccess.city.ac.uk/ / link to published version: copyright and reuse: city research online aims to make research outputs of city, university of london available to a wider audience. copyright and moral rights remain with the author(s) and/or copyright holders. urls from city research online may be freely distributed and linked to. city research online: http://openaccess.city.ac.uk/ publications@city.ac.uk city research online http://openaccess.city.ac.uk/ mailto:publications@city.ac.uk karen seago, aspects of gender in translations of “sleeping beauty’, translation, transformation and reception, comparative critical studies, : , pp. - page of - aspects of gender in translations of ‘sleeping beauty’ inspired by the romantic interest in folk songs and stories, jacob and wilhelm grimm started collecting traditional tales from written and oral sources in the first decade of the nineteenth century. they saw these tales as evidence of an ancient german literature in danger of extinction and initially conceived their kinder- und hausmärchen (a literal translation could be tales for children and the home) as a scholarly resource, which would record the material in unedited form and include an apparatus giving information on sources, variants and contaminations. between and , they continued revising the corpus of tales, adding, removing and merging stories; by the final edition of the kinder- und hausmärchen (hereafter khm) contained tales and legends. in the course of german reception, the collection also increasingly moved away from its original scholarly orientation and became more and more a children’s book. deviating from their original intention, wilhelm substantially edited the stories in content and form throughout the seventeen editions of the khm. in the process, he created not only a unique voice but also a distinct genre, which was taken for many years as the prototypical model of the german fairy tale; it made the khm a classic of german children’s reading matter and one of the most translated works of german literature. edgar taylor’s rendering german popular stories was one of the earliest translations of the khm and the first translation into english. it was a highly influential text, which was reissued throughout the century and is still popular today. nevertheless, in every single decade of the nineteenth century there were new english translations of the khm. all of them were selections from the stories in the khm, ranging from a handful of tales to stories, until margaret hunt’s scholarly translation in , which for the first time translated the complete corpus of all tales in one collection and also included the critical apparatus. margaret hunt’s translation is unique among english translations; it is a remarkably uninflected rendering, which does not shy away from sensitive topics and the depiction of sexuality, violence and profane material. in this she differs markedly from all other nineteenth century translations, which took care not to offend the children’s reading market where fairy tales were considered for a large part of the century as morally dubious and insufficiently didactic reading matter. english translations of the kinder- und hausmärchen inserted the german tales into the context of english children’s literature, adapting the tales to its genre conventions and often casting them in the tradition of established sub-genres, such as the moral story or, later in the century, the adventure story. translating the kinder- und hausmärchen as children’s literature also introduced a more consciously socializing framework in which the representation of male and female characters was made to conform to norms of nineteenth century gender expectations. this article will draw on the textual analysis of all (eight) nineteenth century translations of ‘dornröschen’, known today in the international canon as ‘sleeping beauty’. this tale lends itself particularly well to a study of gender behaviour because the story revolves not only around the infraction of an interdiction (the paradigm of female curiosity), but also because it involves such a range of different gender roles, which are articulated across sex, age and class. in addition, the story contains a number of ‘rich’ points, where tensions exist between expectation and behaviour and where characters appear to transgress the norms of what is considered karen seago aspects of gender in translations of‘sleeping beauty’ appropriate gender conduct. amongst other issues, these involve the dubious circumstances in which the queen learns that she has, at last, conceived a child, the king’s responsibility for bringing about the curse on his daughter, the representation of the ‘good’ fairies and the ‘bad’ fairy, and the parents’ neglect of their daughter on the crucial day. while the german text also shows uncertainties around the depiction of these moments (there is continuous editing across the editions), a detailed textual study of the english translations shows that they are far more interventionist in how they deal with these ambiguous elements. there is a clear trend to render all male and female characters so that they conform to normative nineteenth century gender characteristics. the king, for example, is exonerated from being responsible for his daughter’s fate in various ways. in the german text, the thirteenth fairy curses the young princess because she had not been invited to the feast the king had ordered in his joy over the birth of his daughter. but because he had only twelve plates, and there were thirteen wise women in his kingdom, he decided that one of them had to stay at home. in the majority of the nineteenth century english translations, this implied lack of paternal care, and even more importantly, lack of foresight, is perceived as highly problematic and the passage is revised so that the king cannot be held responsible for the decision not to invite all the fairies. strategies range from abstract phrasing, which glosses over the king’s responsibility and weakens his link to the fateful invitation, to more interventionist additions and deletions on the source text meanings and even a shifting of motivation. edgar taylor’s translation is an example where the exoneration is achieved through abstract phrasing in the target text. the simple german konnte er eine nicht einladen (khm, : ) which can be translated as ‘he could not invite one of them’ is rendered as ‘he was obliged to leave one of the fairies without an invitation’(taylor, ). the grammatical shift from active to passive voice suggests that the king’s decision is to some extent determined by other factors, outside his control; this is reinforced by the lexical choice ‘obliged’ which also implies that he is acting against his better judgment. matilda louisa’s translation uses a similar strategy. the clauses which deal with the lack of plates and the sending out of invitations are restructured into a gerund and an impersonal passive: ‘but having only twelve golden plates, invitations were only sent to that number’. (davis, ) this removes the king as subject from these phrases and results in a shift of responsibility by concealing the agent responsible for the invitation. a more pronounced intervention can be found in mrs. h. h. b. paull’s version, which entirely restructures the invitation passage: grimm ( : ) er ladete … auch die weisen frauen dazu ein, damit sie dem kind hold und gewogen wären. es warn ihrer dreizehn in seinem reiche, weil er aber nur zwölf goldene teller hatte, von welchen sie essen sollten, so mußte einen von ihnen daheimbleiben. literal he … invited ...also the wise women, so that they be favorably disposed towards the child. there were thirteen of them in his realm, but because he only had twelve golden plates, from which they should eat, one of them had to stay at home. paull ( ) he … invited … also the wise women, who could endow his daughter with fairy gifts. there were thirteen of these wise women; but only twelve were invited, and twelve golden plates were placed for them. this restructuring removes the reason why only twelve of the thirteen fairies are invited and avoids spelling out the consequences of this limited invitation. the place setting of the twelve golden plates becomes an entirely redundant detail and the tone of the passage is brisk, authoritative and does not give space in which the king is associated with doubt, failure or even a sense that the limited invitation is fateful as the source text does. the most explicit strategy is to separate the king completely from any involvement and to shift responsibility for the fateful invitation to the fairies to another character. in taylor’s revised translation, it is the queen who is to blame, while it is the thirteenth fairy in an anonymous translation of . here the exclusion of the uninvited fairy is rationalized in a circular argument by introducing a shift in the motivation for the invitation, which ultimately holds her responsible. in this translation a qualified invitation is issued; only those ‘wise women who are kind and affectionate to children’ (wehnert, ) are invited; when the excluded fairy attends the feast in a rage and curses the child to die on her fifteenth birthday, she proves that she does not qualify as ‘kind and affectionate to children’ and that she therefore could not or should quite rightly not have been invited. the fault is her own, the reason for her exclusion lies in her nature; the king’s decision not to invite her was right and his judgment is shown to be superior. showing the king to be in control of the situation is an important element in the english translations. in line with nineteenth-century conceptions of manliness which were in the process of being constructed and were mediated through the public schools and children’s literature, he and the prince acquire ‘manly’ traits such as rational decision-making, patience, authority, rationality, control over themselves and others. the king’s emotional responses to his daughter illustrate the different attitudes to what extent men can be seen to express feelings or even have them in the german source texts and the english target texts. in the german texts, the king’s reaction to the birth of his daughter is highly emotional and it is increased in the editorial process. in the first edition of , the king is ‘so pleased’ (so erfreut, ) that he orders a feast. from onwards, his joy is so great that he loses control of his faculties, even to some extent his reasoning faculties. the meaning of the german phrasing ‘vor freude sich nicht zu lassen wußte’ ( : ; : ) is that the king ‘did not know what to do for joy’ but also ‘did not know what to do with himself for joy’. this excessive emotional state and loss of control is a feature which the english translations are careful to temper and in some instances even remove. davis chooses ‘the king in his joy hardly knew what to do’ ( : ) which shifts the focus away from the emotion to a decision-making process. neither taylor nor g. cunningham ( ) allow any suggestion that the king might be overcome: taylor replaces the german king’s rapture with single-minded attention when he translates the phrase as ‘the king could not cease looking on it [the baby] for joy’ ( : ) while cunningham removes any mention of emotion: ‘her father was never tired of gazing upon her’ ( ). similarly, when the curse and its mitigation have been announced, in the german source text everybody is shocked and frightened, and these reactions are increased in the course of the editing. the english translations again tone them down and in some instances take care to separate the king from the rest of the company in this expression of fear. paull’s translation goes even further in its attempt to establish the king as entirely rational, completely in control of any emotion and possessed of calm decision-making and foresight. in his attempt to protect his child from the curse (that his daughter should pierce herself on a spindle and fall into a one-hundred year sleep), the german king immediately orders the destruction of all spindles in his realm. however, paull shifts the point at which the father takes this decision away karen seago aspects of gender in translations of‘sleeping beauty’ from the moment of the curse to the time fifteen years later when the curse is supposed to strike. grimm ( : ) ‘es soll aber kein tod sein, sondern ein hundertjähriger tiefer schlaf, in welchen die königstochter fällt.’ der könig, der sein liebes kind vor dem unglück gern bewahren wollte, ließ den befehl ausgehen, daß die spindeln im ganzen königreich sollten verbrannt werden. literal ‘but it shall not be death, but a hundred year-long deep sleep, the king’s daughter shall fall into. the king, who dearly wanted to protect his dear child against the misfortune, issued the order that all spindles in the entire realm were to be burnt. paull ( ) ‘the king’s daughter shall not die, but a deep sleep shall fall upon her, in which she shall remain for a hundred years.’ the little child, who was endowed with such wonderful gifts, grew up to be the delight of her parents. but, as she approached her fifteenth year, the king became very unhappy and issued a decree that all the spindles in his kingdom should be burnt. instead of a panic-stricken, emotionally determined response, the king’s delayed reaction in paull’s translation demonstrates his manly ability to rise above the situation, assess the danger and issue appropriate orders when necessary. the ability to wait and a capacity for rational deliberation are also traits evident in the portrayal of the saviour-prince in paull’s version. in the german source text and all other english translations, the prince immediately sets out to breach the hedge of thorns once the old man has told him of the sleeping princess in the castle hidden among the thorns. paull’s phrasing and narrative structuring, however, suggest an interval: the prince, when he heard his grandfather talk of the fate of former princes who had tried to force their way through the hedge of thorns, and how they were caught by the bushes, and died a miserable death, would say, ‘it matters not to me, i have no fear; i am determined to discover this beautiful may blossom.’ the good old man gave up attempting to dissuade the willful prince, and said no more. just at this time the hundred years had nearly come to a close, and the day at last arrived for may blossom to be awaked from her long sleep. on this very day the prince started on his enterprise… ( ) together with a concern to show dominant male characters in control of their emotions (the prince, for example, is not directly influenced by the princess’s beauty to kiss her as he is in some editions of the german source text), issues of authority and power are also evident. most english translations are keen to establish the king’s sovereignty by introducing phrases which accentuate this aspect. lexical choices show a preference for directive verbs such as ‘ordering’ (wehnert, ; hunt, ), ‘ordaining’ (crane, ) or ‘proclaiming’ (davis, ) rather than ‘arranging a feast’ (ein … fest anstellte, : ; : ) or by inserting additional references to the king’s ‘dominions’ where the source text is unspecific (davis, ), and insisting on the personal pronoun to link objects and persons to the king where the german uses the definite article (davis, - ). when the king ‘gave the order’ (ließ den befehl ausgehen, : ; : ) for the destruction of the spindles, this is reinforced in several of the english translations: ‘issued an order directing’ (cunningham, ), ‘issued a decree commanding’ (wehnert, ), ‘issued a decree’ (paull, ). davis is particularly expansive, adding a clause to the order of destruction that the king also ‘appointed officers to see it carried out’ (davis, ). female characters, on the other hand, are infantilized, restricted to the female sphere of house, garden and nursery (again in explicit interventions which contradict the source text), are over-emotional and irrational, and cannot judge long-term implications. this applies to all female characters but i will concentrate here on the representation of the fairies. in the german, these are powerful, semi-divine beings who have the power over life and death and as ‘wise women’ (weise frauen) are related to the norns or fates of nordic and greek myth respectively. in the english translations, these mythic powers are humanized, domesticated and in some translations associated with the nursery and its trivialities. five of the nine translations do not refer to them as ‘wise women’ but render this as ‘fairies’, a term which, especially in the first half of the nineteenth century, was closely associated with the saccharine flower fairies of didactic and moral tales who not only were much smaller but were also representations of female virtues such as patience or meekness. with this loss in stature, and the loss of ‘wisdom’ as an explicit attribute in their name, the fairies are further portrayed in some translations as rather silly and prone to feminine competition. in his revised version of , taylor has them wear exaggerated fashions, ‘each with a high red cap on her head, and red shoes with high heels on her feet, and a long white wand in her hand’ (taylor, ). cunningham’s translation foregrounds the family context by presenting all the fairies as ‘sisters’. in addition, the relationship between these sisters is drawn in terms of competition, rather like the competitiveness amongst children in the nursery. cunningham expands the twelfth fairy’s direct speech and has her condemn the immaturity of ‘her spiteful sister.’ (cunningham, ) nursery associations are also prominent in davis’s rendering when she translates the passage where the twelfth fairy mitigates the death curse as ‘apply[ing] some remedy against the effect of the thirteenth fairy’s decree’ (davis, ). this calls to mind a mother’s reaction to a simple childhood hurt, more closely associated with sticking a plaster on a superficial injury rather than responding to the threat of death and having the power to overcome death. narrative logic requires the mitigation of the curse by one of the fairies, and none of the translations goes so far as to assign this feat to another character; nevertheless, the english versions are reluctant to allow a representation of the fairies as supreme beings and downgrade any manifestation of their power through the lexical choices made. their ‘magic gifts’ (wundergaben, : ; : ) are rendered as ‘fairy gifts’, for example, by paull ( , ), ‘best gifts’ by taylor ( : ), or ‘wonderful gifts’ (cunningham, ; wehnert, ; paull, ; crane, ). the last, although a close rendering, does not have the primarily powerful and supernatural connotations that the german wundergaben has. as a further strategy to minimize their presence and influence in the text, the fairies are backgrounded through the use of indirect speech instead of the direct speech in the german source texts. märchen (fairy tales) are simple narrative forms in which dialogue is highly ritualized and direct speech only occurs at crucial moments, uttered by important characters. in her study of the distribution of direct speech in the khm, ruth bottigheimer has shown how good female characters are increasingly silenced, with indirect speech or narratorial summary replacing their direct utterances. negative female characters, on the other hand, retain their direct speech to some extent but, in contrast to male characters, for them it is a measure of their evil. this is a pattern which can also partly be traced, in the english translations. while it is only in taylor’s versions ( : - ; : ) that the twelfth fairy loses her direct voice for the mitigation, most translations emphasize the loudness, anger, disturbing presence of the thirteenth fairy. in the german source texts, the anger of the thirteenth fairy is presented, at least in the early editions, as justified. she has extended direct speech in which she explains why she has come to curse the child. in later editions, this direct justification karen seago aspects of gender in translations of‘sleeping beauty’ is replaced by narratorial summary and the extent of her justification is toned down. nevertheless, there remains a sense of the injustice done her and that she is acting, if not in an entirely justified way, then at least in a way that is understandable given the circumstances. in the translations, this double perspective, which shows the thirteenth fairy in a rational light, is removed. she is represented as overemotional and irrational and her reaction as unjustified when her anger is ridiculed by translating the offence, which had caused it as a trivial ‘affront’ (davis, ) or as ‘disrespect’ (cunningham, ). while thus the cause for her behaviour is minimized, at the same time her reaction to it is increased: in cunningham she is ‘greatly incensed’ ( ), wehnert shows her in a ‘tremendous passion’ ( ), while she is ‘burning to revenge herself’ in crane ( ). in the german, she wants to revenge herself for her exclusion (wollte sich … rächen, : ). as a result, the thirteenth fairy’s behaviour is delegitimated; she transgresses expectations of how women were expected to behave by not accepting with good grace her exclusion from the feast. advice given to women by influential conduct book writers counseled that a woman proved herself a ‘rational being’ if she bore ‘provocation’ with ‘equanimity’ and did not contest her husband (or other male guardian) in an argument but stayed silent and meek even if she had been wronged. mrs. chapone, whose conduct books were popular throughout the nineteenth century, states categorically that ‘an enraged woman is one of the most disgusting sights in nature.’ in taylor’s revised version, the thirteenth fairy is shown as particularly transgressive. when she arrives, she is identified at a distance by the great noise she makes in the courtyard, dressed like the archetypal witch ‘with a black cap on her head, and black shoes on her feet, and a broomstick in her hand’, she ‘was very angry, and scolded the king and queen very much, and set to work to take her revenge.’ (taylor, ) crucially, it is not only her behaviour, which is seen as reprehensible, but the evil is presented as part of her nature. wehnert ( ) and cunningham ( ) refer to her as explicitly ‘evil’, cunningham as ‘spiteful’ ( ) and paull as ‘bad’ and ‘wicked’ ( ). she is demonized and excluded from the circle of humanity, which she disrupts, while the twelve ‘good’ fairies are humanized, domesticated and integrated into the private sphere with an affinity for the occupations of nineteenth century femininity. this results in a clear division into good and bad women, which serves as a model to inculcate appropriate behaviour in girls. in addition, the ‘bad’ fairy acquires attributes which identify her as a social outcast. in comparison to contemporary texts on the woman question or prostitution, for example, she is described in exactly the same terms as single women, or as prostitutes – both seen to be a great social problem around the mid-century. she is noisy and protesting, according to contemporary conduct books a sure sign of moral collapse where a woman’s complaints about her husband (however justified) were seen as a betrayal, the first step to adultery, which would inevitably lead to prostitution. furthermore, in popular articles and medical discourse a loud, harsh or hoarse voice was named as one of the marks by which a prostitute could be identified; a matter of great concern in the fifties and sixties when the ‘social evil’ of prostitution created great anxiety over its possibility of infecting ‘healthy areas’. in a similar way that public debate agonized over how streetwalkers could be excluded from contact with decent women, the treatment of the thirteenth fairy in the translations shows concern over how to exclude her polluting influence. in addition to these general trends, which are articulated in a more or less pronounced way in the eight translations analyzed, there are also distinct differences in tone and orientation between the different translators which can be traced to historical context, but also to gender. in the following i will analyze two translations as an example for a gender-biased agenda, which is revealed in the translators’ choice and interventions. taylor’s early translations develop a clear anti-female agenda which is read against historical context while crane’s late version shows a submerged protofeminist voice which engages with contemporary debates on femininity. the german texts certainly showed in their editorial treatment that they responded to social norms of expected gender behaviour. nevertheless the role of the khm providing evidence for an established german cultural identity in the political endeavour for a unified german nation state protected the german tales to some extent. socially and didactically motivated editorial interventions threatened to remove the tales too far from their postulated origin in nordic myth which the grimms saw as proof of an historical german literature. representations which were grounded in the tales’ mythic origin were maintained even if they did not conform to social norms. in the case of ‘dornröschen’, this applies specifically to the character of the wise women / fairies, and the depiction of nature. the kinder- und hausmärchen are characterized by an organic worldview, where nature, man and woman exist in a state of mythic oneness. in contrast to this, the english texts as a rule establish man as a separate entity, clearly divorced from nature but also separated from woman. my previous discussion of male and female gender roles has already shown how the english translations introduced and maintained separate spheres for men and women. this was particularly evident in the treatment of the fairies whose powerful agency in the german source texts aligned them more closely with the male sphere of work and decision-making. in the translations they are removed into the female sphere, domesticated and identified with nurture and the nursery. the ideology of separate spheres is enunciated particularly strongly in taylor’s translations. in his version he had changed the motif where the queen learns about her pregnancy from a crab. in the german text this occurs when the queen is bathing in a natural pond, where the crab, later a frog, shares the water with her. the sexual overtones of this scenario created problems for almost all english translations. in taylor’s rendition, the queen takes a walk by the river instead and a little fish raises its head out of the water to announce her pregnancy, thus protecting her modesty and virtue against any implications of untoward behaviour. in his revision, taylor further changed this motif. the queen still takes a walk, but this time the river along which she strolls runs at the bottom of the castle’s garden, firmly protected in the private enclosure of the domestic sphere. he also introduces further evidence of her female virtue: this time the little fish lies gasping on dry ground and the queen rescues it by throwing it back into the water. it is this act of charity which motivates the fish’s prophecy that the queen shall bear a child. taylor has rendered this motif in a way which firmly inserts the tale into an established fairy tale paradigm: the queen’s pregnancy is a reward for a good deed, and by the conventions of the genre this further establishes her as a blameless character. taylor’s version clearly emphasizes marriage; he explicitly states that ‘the couple have been married for many years’ ( ). he stresses that the queen is not attempting to go beyond the boundaries of her married state, both materially (she stays in the garden, within the confines of the marital home); and symbolically (any suspicions about the pregnancy are precluded by her virtuous act and the grateful animal’s reward). taylor also stresses the marital couple: in contrast to the german source text where the queen is marginalised once the baby is born, the king and queen in his version are a unit. it is the couple who discuss the celebration, the couple who do not karen seago aspects of gender in translations of‘sleeping beauty’ own sufficient numbers of golden plates, the couple who are rebuked by the angry thirteenth fairy. however, while this gives the queen a visibility which she does not enjoy in any of the other translations, this strategy also ensures that responsibility for the fateful further development is to some extent removed from the king. in actual fact, this exoneration of the king is ensured explicitly in taylor’s treatment of the motif where the invitations to the feast are issued. the invitation is split so that it is the king who invites the harmless friends and relatives but it is the queen who insists that the fairies are invited as well. it is thus the queen who is solely responsible for initiating the actions which will result in her daughter’s calamity. taylor’s intervention has further implications. the queen has been established as a chaste wife and mother, a paragon of feminine virtues, but this positive representation applies only as long as she stays within the parameters of the domestic sphere. the moment she transgresses the boundaries of female responsibilities and ventures to make decisions with far-reaching consequences her actions are placed in a negative context. taylor ascribes a positive motivation to the queen’s wish to invite the fairies: it is her concern to provide for her daughter, to secure the fairies as powerful patrons. but the outcome of the story proves that this positive wish is misguided, that it leads to disaster and that ultimately the queen needs to be guided by a male to make decisions that go beyond the merely domestic. in addition to the suggestion that it is highly problematic for women to have an opinion of their own because they are incapable of weighing up the consequences of their actions, taylor’s revision also implies that women’s speech is dangerous. he gives the queen direct speech to insist on her desire, and, importantly, to oppose the king: ‘but the queen said, “i will have the fairies also, that they might be kind and good to our little daughter.”’ ( ) read against historical context, this insistence on women’s inability to judge what is good for their children, even if their intentions are good, is particularly revealing. at the time of taylor’s revision, women in britain were subject to their husband’s rule. considered minors by law, they had no legal rights to any possessions, not even money they earned themselves, and even more importantly, they had no legal say in the education of their children nor were they their legal guardians. the position of the father as sole parent and women’s suitability for custody had been a matter of intense public debate since , two years before taylor’s revised version came out. caroline norton was a chaste and virtuous wife who had left her abusive husband out of concern over her children’s safety. in her fight for custody of her three sons, she wrote two pamphlets in an attempt to influence public opinion and force a debate in parliament. while her first pamphlet, the natural claim of a mother to the custody of her child as affected by common law right of the father did not succeed in swaying opinion sufficiently (the bill brought by serjeant talfourd to change the law of custody was thrown out by the lords), her second attempt, a plain letter, submitted under a male pseudonym, decisively influenced the passing of the infant custody bill in which gave women charge of their children under the age of seven. the queen in taylor’s version is, like caroline norton, a deeply conflictual figure. both norton and the queen conform to the expectations of the dutiful wife and mother; nevertheless, both transgress their natural role and take upon themselves responsibilities and decisions outside their sphere. they both intervene with male authority to influence their children’s future life – in the case of the queen with disastrous consequences. given the socialising impetus of fairy tales, taylor’s revision promotes a traditional view of parental responsibilities, querying the suitability of women for a guardian’s role. the text’s critical attitude to female intervention in the public domain can also be seen in the representation of the fairies, and in particular in the treatment of the ‘thirteenth’ fairy which suggests further parallels between caroline norton and undesirable female behaviour. taylor clearly establishes a dichotomy of the good and bad woman, which is articulated through external attributes and behaviour. the good fairies are dressed ‘each with a high red cap on her head, and red shoes with high heels on her feet, and a long white wand in her hand’ ( ), while the bad fairy arrives with ‘a black cap on her head, and black shoes on her feet, and a broomstick in her hand’. dressed like this, she is unambiguously identified by taylor as a witch, a representation deeply contradictory to the german source text editions, which never explicitly identify the thirteenth fairy as bad and continue to call her a ‘wise woman’ by implication. all aspects of her behaviour are exaggerated to create a deeply negative portrayal, transgressing all norms of female behaviour: … a great noise was heard in the courtyard, and word was brought that the thirteenth fairy was come, with a black cap on her head, and black shoes on her feet, and a broomstick in her hand: and presently up she came into the dining-hall. now as she had not been asked to the feast she was very angry, and scolded the king and queen very much, and set to work to take her revenge. ( ) the th fairy behaves in direct opposition to what is expected of a good wife, and, of course, she does exactly what caroline norton was doing. she generates a lot of noise in the public domain, she is being talked about, and instead of bearing the provocation of being excluded from the feast, she insists on attending. intruding into an environment where she is not wanted, as caroline norton intruded into parliament with her petitions and into public debate with her actions, she challenges the decision of the king, as norton challenged the law of the land. her behaviour and her actions clearly mark her as an outcast, and also prove that ultimately the king’s decision to exclude her was the appropriate one after all since she is clearly not fit to participate in polite society. in contrast to this, the good fairies are assimilated into the domestic and female sphere; they form a circle of well-meaning and care, showering the little princess with all the virtues a good girl needs: ‘they gathered round in a ring and gave all their best gifts to the little princess. one gave her goodness, another beauty, another riches, and so on till she had all that was good in the world.’ ( ) taylor creates a clear dichotomy of acceptable and unacceptable behaviour in women and associates this with generally accepted characteristics for deviancy thus establishing a strict code of conduct for a good woman. in portraying the protesting woman in terms that link her with prostitution, he articulates an anxiety over the status of single women, which had become a matter of general concern and would become a matter of intense public debate after the census of provided statistical evidence of the large proportion of unmarried women. in the ‘woman question,’ as this debate became known in england, unmarried women were referred to as ‘odd’ women, were treated with pity and contempt and regarded with distrust. their unmarried state was seen as a problem since it barred them from their role as mothers for which nature and instinct had predestined them. unable to fulfill this role, they were seen as unnatural and deviant and a danger to stable society. in contrast to taylor’s repressive script where even the good woman (the queen) is in danger of straying into unnatural territories (when she insists on inviting the fairies), lucy crane’s late nineteenth century translation inserts meanings which karen seago aspects of gender in translations of‘sleeping beauty’ reverse the trends established by most previous translations, offering a gender dynamic which is supportive of female roles and critical of male roles. unusually, crane does not introduce any changes or translation choices which align female roles in the story to conform to models of propriety. her version is unconcerned with the sexual implications of the bathing scene which troubled other translators and she even endows the princess with the gift of ‘cleverness,’ a quality universally understood to be an unattractive and even unnatural attribute; for the conduct book writer dina craig, for example, a clever woman ‘is not properly a woman.’ in contrast to the pervasive belief that cleverness is an obstacle to romance - ‘man is wisely averse to ‘cleverness’ in a woman’ declares one of the characters in a popular late nineteenth century novel by mary cholmondeley - in crane’s version, it is precisely this characteristic in the princess that appears to cause her being loved spontaneously by everybody. grimm ( : ) … es war so schön, sittsam, freundlich und verständig, daß es jedermann, der es ansah, lieb haben mußte. literal … it [sic] was so beautiful, virtuous, friendly and understanding that anybody who looked on her, had to hold her dear. crane ( ) … she was so lovely, modest, sweet, and kind and clever, that no one who saw her could help loving her. this is a good example for crane’s technique in producing a female-oriented version. unlike taylor who added, removed and rewrote whole passages, crane’s strategies are less dismissive of the source text and far subtler. in the example above, crane introduces ‘clever’ in an attempt to render the full meaning of the german verständig which means both ‘kind’ and ‘clever’ in german. other translators had chosen to restrict themselves to only one of the two meanings, and left out the quality with negative connotations. similarly, crane’s decision to translate the german princess’s name ‘dornröschen’ (literally ‘little thorn rose’) as ‘rosamond’ ( ) confers upon her an individuality which is further substantiated when crane’s text also minimizes those descriptions of the princess which foreground her as a relational being: she refuses to translate königstochter as ‘king’s daughter’, opting for ‘princess’ ( ) instead, but has no problem with rendering königssohn as ‘king’s son’ ( ). crane also takes care to minimize the suggestion that beauty is a fundamental attribute in winning love when she restructures and summarizes the paragraph where the prince finds her in such a way that the link between her beauty and his compulsion to kiss her is weakened. and finally, it is not the king who gives the princess’s hand in marriage (as in paull’s version of ) or the prince who marries the princess as all other versions depict the happy end; crane’s version foregrounds a ceremony in which both partners are equally involved when they marry each other: ‘then the wedding of the prince and rosamond was held’ ( ). a similar interest in establishing, if perhaps not full equality, then comparability between the sexes can be seen in the way that crane frames the description of the prince and princess finding the little chamber in the tower. unusually, crane expands on the german source text to introduce a description of the prince climbing the stairs, which is phrased in such a way that it mirrors the experience of the princess. princess (crane, ) till at last she came to an old tower. she climbed the narrow prince (crane, ) and at last he came to the tower, and went up the winding stair, and literal and finally he came to the tower grimm ( : ) und endlich kam er zu dem thurm winding stair opened the door and opened the door und öffnete die türe establishing such a parallel between the prince and princess signals a similarity in male and female experience which is in stark contrast to the prevailing ideal of a complementarity of the sexes. the ideology of separate spheres rested on an understanding of a fundamental qualitative difference between the sexes formulated in terms of inherently different characteristics and a biological disposition that suited men and women to different tasks. this sexual differentiation had found its most enduring symbolization in coventry patmore’s popular poems in the angel in the house ( - ) and was articulated by john ruskin in his popular lecture series ‘of queen’s gardens’ ( ): the man's power is active, progressive, defensive. he is eminently the doer, the creator, the discoverer, the defender. his intellect is for speculation and invention: his energy for adventure, for war, and for conquest, wherever war is just, wherever conquest necessary. but the woman's power is for rule, not for battle, - and her intellect is not for invention or creation, but for sweet ordering, arrangement, and decision. she sees the qualities of things, their claims and their places. her great function is praise: she enters into no contest, but infallibly judges the crown of contest. ( - ) patmore’s and ruskin’s terminology of domestic angels and queenly gardens influenced the representation of an ideal of femininity in all spheres of public and artistic expression and also found its way into contemporary adaptations of the fairy tale of sleeping beauty in literature and art. particularly important for crane’s translation is a series of paintings by the pre-raphaelite edward burne-jones, which provide an interesting foil for an analysis of crane’s translation choices. burne- jones’s ‘briar rose’ series contains four images, two of which are fairly conventional choices of the prince passing through the hedge and the princess lying asleep. crucially, the two remaining scenes are dedicated to a depiction of the male and female domain. the king is shown, alone and surrounded by councillors, on his throne in ‘the council room while ‘the garden court’ shows the female sphere. accompanying verses by william morris convey the separation of men and women in their tasks as well: the council room ( ) the threat of war, the hope of peace the kingdom's peril and increase. sleep on, and bide the latter day when fate shall take her chains away. the garden court ( ) the maiden pleasance of the land knoweth no stir of voice or hand, no cup the sleeping waters fill, the restless shuttle lieth still. in contrast to such a clearly articulated separation of the male and female, where burne-jones’s king is interrupted in affairs of state by the sudden onset of sleep, still holding important papers in his hand and surrounded by his councilors, crane’s version includes the queen in the council chamber. while this is partly due to the source text where the king and queen are surprised by the enchantment just as they had entered the throne chamber, nevertheless we have here again a subtle shift where translation choices further emphasize connection and parity of status between the sexes rather than separation and differentiation. in the german text, the prince finds the king and queen ‘lying asleep up by the throne’ (und oben bei dem throne lag der könig und die königin, ); crane translates this in the plural as ‘on their thrones, slept the king and the queen,’ ( ) giving the queen her own throne and thus signalling her inclusion and participation in matters of the throne room rather than her exclusion to the sweet affairs of the garden court of female company. karen seago aspects of gender in translations of‘sleeping beauty’ textual changes to how the king and queen are treated further support an agenda in favour of connection rather than separation of the sexes. problematic decisions and actions taken by the couple together are rendered in a way which minimizes negative connotations while those actions which are taken by the king alone are more negatively inflected. the fact that the king and queen leave their child alone on precisely the day when the curse is supposed to strike had proved problematic for all translators and crane is not alone in mitigating the parents’ responsibility for their apparent lack of care. grimm ( : ) es geschah, daß an dem tage, wo es gerade funfzehn jahr alt ward, der könig und die königin nicht zu haus waren literal it happened that on the very day, when it [sic] turned fifteen, that the king and queen were not at home crane ( ) it happened one day, she being already fifteen years old, that the king and queen rode abroad in crane’s rendering, the parents leave her alone after the dangerous day has passed and are thus absolved of any fault. in addition, crane’s translation of their absence avoids the possible negative associations of ‘not being at home’ by choosing the vaguer description that they ‘rode abroad.’ she also suggests that the parents had returned home for some time before the curse struck and were thus, in fact, present at the fateful moment (in the german, they enter the great hall just when the curse strikes). grimm ( : ) der könig und die königin, die eben heimgekommen und in den saal getreten waren literal the king and queen who had just come home and had stepped into the hall crane ( ) the king and queen, who had […] returned and were in the great hall similar subtle changes in emphasis and lexical choice result in a shifting of responsibility and an intensification of the king’s guilt in his decisions surrounding the celebration of the birth of his daughter. grimm ( : ) es waren ihrer dreizehn in seinem reiche, weil er aber nur zwölf goldene teller hatte, von welchen sie essen sollten, so mußte eine von ihnen daheimbleiben. … das fest ward mit aller pracht gefeiert literal there were thirteen of them in his realm, but because he only had twelve golden plates, from which they should eat, one of them had to stay at home. … the feast was celebrated in all its splendor crane ( ) there were thirteen of them in his kingdom, but as he had only provided twelve golden plates for them to eat from, one of them had to be left out. however, the feast was celebrated with all splendour the german text gives a fairly neutral, and inevitable, reason why one of the fairies was not invited: the king only had twelve golden plates. crane’s decision to translate the german hatte (had) as ‘had provided’ ( ) identifies the king as responsible – the insufficient number of plates is the result of the king’s decision, he could have ‘provided’ more. this shift towards foregrounding the king’s culpability in bringing about the curse on his child is further reinforced in crane’s translation choices in the phrase which names the consequences of the lack of plates. in the german, this is again rendered as an inevitable situation, almost as fateful: so mußte eine von ihnen daheimbleiben (therefore one of them had to stay at home, ). crane’s translation of this - ‘one had to be left out’ ( ) – moves away from the inevitability of the german and suggests human agency and preference in the lexical choice of ‘leaving somebody out’. a sense of wrong-doing, which is entirely absent in the german, is further introduced when crane adds the qualifying conjunction ‘however’ to link the passage describing the lack of plates with the celebration going ahead ( ). this suggests an awareness that perhaps the feast should not have been celebrated under the circumstances. and this expectation of a retribution for the king’s decision to exclude one of the fairies is confirmed by a range of very small changes in the description of the fairy’s arrival at the celebration. crane drops any qualifiers which suggest surprise at the fairy’s appearance instead creating a sense of logic and the curse as an expected outcome of the slight: : grimm ( : ) als elfe ihre sprüche eben getan hatten, trat plötzlich die dreizehnte herein literal just as eleven had had their say [given their blessing], suddenly the thirteenth entered crane ( ) and when eleven of them had said their say, in came the uninvited thirteenth such textual moves which reinforce the king’s guilt and exonerate to some extent the fairy’s curse are in stark contrast to all other english translations which had instead taken care to exonerate the king and create a representation of the fairy as witch. thus, while it was the single woman who was suspect in taylor’s translation, crane’s text establishes the single, autocratic, decision-making male as the problem. read against burne-jones’s series of paintings with their iconic representation of separate spheres, crane’s translation questions the value of such an ideology and posits connection rather than difference as the ideal. the english texts discussed in this article were all chosen because they identified themselves as translations of the story from the grimms’ khm. other versions of ‘sleeping beauty’ were widely available throughout the nineteenth century, in particular translations of charles perrault’s ‘la belle au bois dormant’ which was first translated into english in by robert samber. perrault’s seventeenth-century version had close links with the german oral versions of the story the grimms collected in the early nineteenth century from contributors with a french background or knowledge of french. wilhelm’s editing of the german tale took care to emphasize those motifs which could be derived from nordic sources. individual english translations of the khm- based text were marginally influenced by representations derived from perrault, such as occasionally emphasizing the link between age and evil in the ‘witch’-figure, a rare use of conventional descriptions of beauty (‘coral lips’) or an isolated instance of reticence on the part of the prince when admiring the sleeping princess. however, as the nineteenth century progresses, a general trend can be observed of a tendency to create a hybrid, international, tale which uses the most popular motifs from the french and the german. this merging is most pronounced in adaptations of the tale for the stage, children’s (picture) stories and versions of the story for the popular market. karen seago london metropolitan university, gb the body of literature on the khm is extensive but heinz rölleke’s work on the genesis and development of the grimms’ collecting and editorial work are of particular relevance here: heinz rölleke, ‘nachwort,’ in brüder grimm kinder- und hausmärchen, ausgabe letzter hand mit den originalanmerkungen der brüder grimm, vols, ed. by heinz rölleke (stuttgart: reclam, ), pp. - and heinz rölleke, ‘zur biographie der grimmschen märchen’, in brüder grimm, kinder- und hausmärchen, nach der zweiten vermehrten und verbesserten auflage von , textkritisch revidiert und mit einer biographie der grimmschen karen seago aspects of gender in translations of‘sleeping beauty’ märchen versehen, ed. by h. rölleke (munich: diederichs, ), pp. - . birgit stolt provides an interesting discussion on the creation of the gattung grimm. ‘textsortenstilistische beobachtungen zur ‘gattung grimm’, in die brüder grimm, erbe und rezeption, stockholmer symposium , ed. by astrid stedje (stockholm: almquist & wikse, ), pp. - . brian alderson, ‘the spoken and the read: german popular stories and english popular diction’, the reception of grimms’ fairy tales, responses, reactions, revisions, ed. by donald haase (detroit: wayne state university press, ), pp. - . most of the translations were based either on the second edition of the khm in or the last edition of . they are the source texts referenced in the discussion of the english translations. the following editions were used: brüder grimm, kinder- und hausmärchen, nach der zweiten vermehrten und verbesserten auflage von , textkritisch revidiert und mit einer biographie der grimmschen märchen versehen, ed. by h. rölleke (munich: diederichs, ), pp. - and brüder grimm kinder- und hausmärchen, ausgabe letzter hand mit den originalanmerkungen der brüder grimm, vols, ed. by heinz rölleke (stuttgart: reclam, ), pp. - . martin sutton, the sin-complex, a critical study of english versions of the grimms’ kinder- und hausmärchen in the nineteenth century (kassel: brüder grimm gesellschaft, ), p. , p. , p. . f. j. h. darton, children’s books in england, five centuries of social life, rev. by brian alderson, (cambridge: cambridge university press, rd edn ), p. and peter butts, ‘the beginnings of victorianism (c. - )’, in children’s literature, an illustrated history hunt, ed. by peter hunt (oxford: oxford university press, ), pp. - . the body of work on english translations of the khm is not large. sutton has provided a detailed analysis of a selection of different stories from the range of nineteenth-century translations in his sin-complex. other studies address individual aspects in the english translations: alderson’s ‘the spoken and the read: german popular stories and english popular diction’; david blamires, ‘the early reception of the grimms’ kinder- und hausmärchen in england’, bulletin john rylands library, : ( ), - ; ruth michaelis-jena, ‘edgar and john edward taylor, die ersten englischen Übersetzer der kinder- und hausmärchen’, in brüder grimm gedenken ii, (marburg: elwert, ) pp. - ; karen seago, ‘shifting meanings: translating grimms’ fairy tales as children’s literature’, aspects of specialised translation, ed. lucile desblache (paris: la maison du dictionnaire, ), pp. - . the translations are: german popular stories, trans. from the kinder- und hausmärchen collected by m.m. grimm from oral tradition, trans. by edgar taylor (london: baldwyn, ), pp. - . hereafter taylor , cited in the text. foreign tales & traditions chiefly selected from the fugitive literature of germany, transl. g. g. cunningham (edinburgh: fullarton & co, ), pp. - . hereafter cunningham, cited in the text. german popular stories and fairy tales as told by gammer grethel, trans. edgar taylor (london: bell, ), pp. - . hereafter taylor , cited in the text. household stories, collected by the brothers grimm, newly trans. with two hundred and forty illustrations by edward h. wehnert, vols (london: addey, ), pp. - . hereafter wehnert, cited in the text. home stories, collected by the brothers grimm, newly trans. by matilda louisa davis, illustrated by george thompson (london: routledge, ), pp. - . hereafter davis, cited in the text. grimms’ fairy tales. a new translation. by mrs. h.h.b. paull, translator of ‘hans andersen’s fairy tales,’ and author of ‘lucy west,’ ‘mary elton,’ ‘pride and principle,’ etc. specially adapted and arranged for young people, with sixteen original illustrations by w. j. weigand. (london: warne, [ n. d., ?]), pp. - . hereafter paull, cited in the text. household stories, from the collection of the bros. grimm, trans. from the german by lucy crane; and done into pictures by walter crane (london: macmillan, ), pp. - . hereafter crane, cited in the text. grimm’s household tales, with the author’s notes, trans. from the german and ed. by margaret hunt, with a preface by andrew lang, m.a. (london: bell, ), pp. - . hereafter hunt, cited in the text. claudia nelson, ‘sex and the single boy: ideals of manliness and sexuality in victorian literature for boys,’ victorian studies : (summer ): - (pp. - ) and j. a mangan & james walvin (eds.) manliness and morality, middle-class masculinity in britain and america, - , (manchester: manchester university press, ) ruth bottigheimer, ‘silenced women in the grimms’ tales: the ‘fit’ between fairy tales and society in their historical context,’ fairy tales and society, illusion, allusion and paradigm, ed. by ruth bottigheimer, (philadelphia: university press of philadelphia, ), pp. - . arthur freeling, the young bride’s book being hints for regulating the conduct of married women. with a few medical axioms (london: washbourne, ), p. . mrs. chapone, letters on the improvement of the mind. (edinburgh: anderson, ), p. . freeling, pp. - . jill matus, unstable bodies, victorian representations of sexuality and maternity (manchester: manchester university press, ), pp. - . judith walkowitz, prostitution and victorian society, women, class, and the state (cambridge: cambridge university press, ), p. . katharine moore, victorian wives (london, new york: allison & busby, ) e. m. palmegiano, women and british periodicals (new york: garland, ), pp. - . mary poovey, uneven developments, the ideological work of gender in mid- victorian england (london: virago, ), p. . dinah maria mulock craik, a woman's thoughts about women (london: n.p. , ), p. . mary cholmondeley, red pottage (london: longman, ), p. . ruth h. bloch, ‘untangling the roots of modern sex roles: a survey of four centuries of change,’ signs ( ): - (pp. and - ). heidemarie bennent traces this to the impact of rousseau’s ideas on gendered education developed in his Émile ou de l’éducation ( ). galanterie und verachtung, eine karen seago aspects of gender in translations of‘sleeping beauty’ philosophie-geschichtliche untersuchung zur stellung der frau in gesellschaft und kultur (frankfurt: campus, ), p. . john ruskin, ‘of queens’ gardens’, sesame and lilies (orpington: george allen, ), pp. - (originally published london: smith, ) burne jones, the legend of “the briar rose”. a series of pictures painted by e. burne jones, a.r.a., exhibited at thos. agnew & sons’ galleries, old bond street, . small pamphlet containing an anonymous adapted translation of ‘sleeping beauty’ under the title of ‘briar rose’ with some amendments and some summaries in the text. the four verses accompanying the paintings are printed after the story and are signed by william morris. the exception is margaret hunt’s source-text-oriented translation which rendered most of the features that other translations adapted to the receptor culture. for a detailed discussion of this see karen seago, ‘constructing the witch’, storytelling: interdisciplinary and intercultural perspectives, ed. by i. blayer and m. sanchez (frankfurt/main, new york: peter lang), pp. - wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ “make it beautiful”. an old request with difficult academic answers. full terms & conditions of access and use can be found at http://www.tandfonline.com/action/journalinformation?journalcode=rfdj download by: [politecnico di milano bibl] date: november , at: : the design journal an international journal for all aspects of design issn: - (print) - (online) journal homepage: http://www.tandfonline.com/loi/rfdj “make it beautiful”. an old request with difficult academic answers. silvia d. ferraris, lucia rampino & venere ferraro to cite this article: silvia d. ferraris, lucia rampino & venere ferraro ( ) “make it beautiful”. an old request with difficult academic answers., the design journal, :sup , s -s , doi: . / . . to link to this article: https://doi.org/ . / . . © the author(s). published by informa uk limited, trading as taylor & francis group published online: sep . submit your article to this journal article views: view related articles view crossmark data http://www.tandfonline.com/action/journalinformation?journalcode=rfdj http://www.tandfonline.com/loi/rfdj http://www.tandfonline.com/action/showcitformats?doi= . / . . https://doi.org/ . / . . http://www.tandfonline.com/action/authorsubmission?journalcode=rfdj &show=instructions http://www.tandfonline.com/action/authorsubmission?journalcode=rfdj &show=instructions http://www.tandfonline.com/doi/mlt/ . / . . http://www.tandfonline.com/doi/mlt/ . / . . http://crossmark.crossref.org/dialog/?doi= . / . . &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . / . . &domain=pdf&date_stamp= - - design for next th ead conference sapienza university of rome - april doi: . / . . © the author(s). published by informa uk limited, trading as taylor & francis group. this is an open access article distributed under the terms of the creative commons attribution license (http://creativecommons.org/licenses/by/ . /), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. “make it beautiful”. an old request with difficult academic answers. silvia d. ferrarisa*, lucia rampinoa, venere ferraroa adepartment of design, politecnico di milano *silvia.ferraris@polimi.it abstract: the evolution of design as a discipline witnessed a controversial attitude towards the role of aesthetics in the work of designers. following the functional creed, in many technical academic entourages evolved the idea that a designer job is anything but developing an aesthetic language. in the meantime, in the not- academic world, outsiders think that design is largely about “making things beautiful”. based on these grounds, the authors have in recent past years started to teach their students to consider the aesthetics of their design by reflecting on the form-giving issue. to introduce it smoothly into a technical university environment, they choose to avoid words such as “beautiful” or “attractive”, rather they speak of “language of products” and of making products “recognizable”. the authors apply this approach in their teaching through the development of specific exercises and tools. in this article, the overall meaning of this kind of experience is discussed to highlight faults and possible further developments in the perspective of an ever-evolving design discipline. keywords: form-giving, aesthetics, product language, product character . introduction . from modernism to postmodernism in the making of this article, the authors report a simple but wicked question, on which they started to reflect on some years ago. in their educational activity at the politecnico di milano they usually find them-selves not asking their students to design “beautiful” products, why is that? in their understanding, one answer comes from an historical reading of the discipline’s evolution. first, design discipline - particularly in europe - roots deeply in the modern era and ideals, which are still eradicated into it. modernity assumption was that of struggling “to conquer the world – as if a better, more beautiful, more humane, faster or more efficient future could be calculated and engineered.” (erlhoff, marshall, , p. ). in this view, rationality became the leading factor in both architecture and design and it developed into teaching programs. very influential has been the impact of the ulm school “the first school of design to place itself absolutely and intentionally in the s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r silvia d. ferraris, lucia rampino, venere ferraro intellectual tradition of modernism” (burdek, , p. ). a school where design evolved toward a more scientific/rational process able to integrate different technical, social, psychological, economic factors and where aesthetics became a less fundamental factor. as such, the school of thought of modernism had significant impact in the way the discipline evolved up until now and, especially, in the way it is taught - even today - in schools with a technical rather than artistic approach. indeed, even if time has passed, in many technical universities, design teachers are expected to teach students to design “functional”, “innovative”, “sustainable” and – lately – “smart” and “engaging” products, rather than “beautiful” ones. it means that the discipline is permeable to collect new concepts into it, such as “sustainability”, but that - in these environments – the approach to aesthetics risks to be still influenced by the original “form follow functions” creed of its dawn age. in the evolutionary prospective of the discipline, however, even the counter-reaction to modernism was not helpful to determine the role of aesthetic in design. indeed, the response to the rational coldness of modernism raised with the opposite assumption of postmodernism that “appreciated ambivalence, irony, arbitrariness, polyphony, triviality and spontaneous human qualities” (erlhoff, marshall, , p. ). indeed, the postmodernist pluralist approach set no boundaries and claimed “beauty” to be subjective, imponderable, and undefinable (burdek, ). this interpretation reinforced the idea – rooted in technical design schools - by which aesthetic factors are not objective and, therefore, tend to be overlooked in technical design-teaching programs. . the comparison with scientific and technical disciplines while the history of design gives a point of view about the reasons why aesthetic contents lack in design programs of technical academia, another reading raised from the authors discussion. possibly, they argue, when design is part of technical schools’ programs, it suffers the comparison of disciplines that are more technical (i.e. engineering) and scientific (i.e. mathematics and physics). those disciplines base their knowledge creation on the application of scientific methods, and strive to collect data that are measurable and objective, to base their research upon. consequently, they have difficulties in comprehending the “soft” nature of design when it deals with qualitative and not measurable data such as aesthetics and user experience. in these technical contexts, design scholars are struggling to prove the discipline authority, challenged by the request of objective evidence, not just at the teaching level, but especially when it comes to doing research in degree thesis and ph.d. dissertations. in such an unwelcoming environment, the aesthetic matter is often overlooked. . the not academic world perspective while the discipline evolved into different schools of thoughts, the world outside academy became more demanding. the authors have a considerable experience of collaboration with industrial companies. therefore, they have witnessed the development of clients’ requests to design. the role of design has gained ground. educated managers know that design can be a key factor for innovation and success (verganti r., ); hence, their expectations are high and regard a large set of design qualities. typically, the new products should at least be “innovative”, “user friendly”, “cost-effective” and - possibly - “green”. nonetheless, even if the demand to design regards several qualities, none of them undoes the basic request for something “functional and attractive”. that is, these two qualities are given for granted. thus, the request to product design always embeds the request to make products also beautiful. about this issue, the authors notice that both the terms “beautiful” and “aesthetic” appears with different levels of meaning, from a shallow to a more educated one. the first case is certainly s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r “make it beautiful” “because a specifically formulated design aesthetic is lacking, the term is usually used in its colloquial sense in the context of design. that is to say: in advertising, marketing, branding, and even elementary design criticism, aesthetic is a loose synonym for “beautiful”, “tasteful”, or “inoffensive”. many who use the term “aesthetics” actually mean “styling”, or identify what are assessed as the beautiful or ugly features of a certain object.” (erlhoff, marshall, , p. ) the second case derives from a growing design culture that gives a wider meaning to the terms “beauty” and “aesthetics” in relation to the values that a product can communicate. in this perspective, a role of storyteller is assigned to designers, who should speak the “language of things”: “design has become the language with which to shape […] objects and tailor the message that they carry. the role of the most sophisticated designers today is as much to be storytellers, to make design that speaks in such a way as to convey these messages, as it is to resolve formal and functional problems.” (sudjic, , p. - ) indeed, when company managers ask for design qualities they generally mean “captivating” and “stylish” objects. the more educated of them are aware that this quality refers not just to shape and color, but also to the overall meaning that is assigned to it in the socio-cultural discourse. (krippenforf, ; verganti, , ) . teaching aesthetic aspects of product design in sum, the authors, who teach product design at the master degree in design & engineering, politecnico di milano, recognized three major factors that characterize the framework of their activity, as regards to aesthetic contents: • the tendency to underestimate the input of aesthetic in product design, due to the design discipline historical background; • the tendency to suffer from an “inferiority complex” about other technical and scientific discipline taught in the same university; • the inescapable demand to designers for the aesthetics of products. in this perspective, the authors introduced both a specific lecture and an exercise to their product design studio. since the very beginning, the aim was to find tools and approaches to deal with the aesthetic matter in a technical degree course. the results proved the exercise prove to be stimulating and largely appreciated by students. the authors first introduced this activity in the academic year / . then, every year they updated it with small adjustments; this article refers to the academic year / . . the reference to product language based on the before-mentioned grounds, the authors started to teach students to consider the aesthetics of their design by reflecting on the form-giving issue. to introduce it smoothly into a technical university, they choose to avoid words such as “beautiful” or “attractive”, rather they speak of the “language of products”. to this end, they define product design as a unity of form and meaning, just like semiotics defines language like a unity of syntax and semantics (bürdek ; krippendorff, ). the analogy between the linguistics syntax - which is “the way in which words are put together to form phrases, s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r silvia d. ferraris, lucia rampino, venere ferraro clauses, or sentences” (merriam-webster, ) – and the syntax of form revels the intent to find the way in which basic elements are put together to form objects. in this perspective, the educational activity focuses on the description of the very basic elements of form (dimensions, proportions, outline, composition, details) and surface (color, texture, finishing) and, after, it defines the way these elements can be combined through different form-giving approaches (“primitive vs free forms” and “additive vs integral”) (see paragraphs . and . ). likewise, the semantics of design has to do with the way we naturally assign meanings to objects in reference to their properties and our experience with them. as said, this attribution come with a specific language and in relation to the socio-cultural context. “the idea that objects have a property is neither natural, culture free, nor universal. they are the result of linguistic attributions. attributions are performed in language, and they reflect the perceptual, emotional, or experimental coordination (linguistic habits or conventions) in a particular community. […] language clarifies, distinguishes, qualifies, and regulates experiences with objects. without adjectival constructions one would not be able to distinguish among the properties of things, the personalities of people and what objects are said to have or not to have.” (krippendorff, , p. ). in the light of this reading, the authors introduce to the students the idea that the design is a human activity by which the physical generation of an object (the syntax) is intrinsically connected to the generation of its meaning (the semantics). then, since “language is a very complex concept” (krippendorff, , p. ), the teachers focus on the concept of character (see paragraph . ) pointing out how the form-giving process of an objects affects the making of its character. the exercise “the form of the product” comprises: an introductory lecture; an analytical exercise and a design exercise, as follows. . the exercise “the form of product” . vocabulary of form and surface terms the introductory lecture describes a vocabulary of terms and two form-giving approaches to use for understanding and analyzing the products. the idea of a vocabulary came up during the design studio courses, where the authors realized that, very often, there were misunderstandings with students due to the lack of a proper vocabulary for discussing the product morphological features. the aim of better defining the vocabulary is, therefore, to share a common language during the form-giving process. together with other colleagues (ferraris et al., ; ferraris b et al., ; gorno and colombo, ), the authors selected a vocabulary of proper terms to help students analyzing the form of industrial products. in more details, the authors selected a list of parameters (i.e. “proportion”) to describe the morphological features; then, for each parameter they chose the corresponding definitions and characteristics, and they selected some images to be as clear as possible. the authors chose the word “parameter” instead of “attribute” (which is also equally applicable); because they wanted to highlight that each parameter defines a physical aspect of the form, which could be measured, even though this analysis is exquisitely quantitative. hence, the effort is to let the analysis be as “objective” as possible, with no intention to say “how” to give form nor to attribute any a-priori value to any parameter. it is strictly a definition of meanings. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r “make it beautiful” for instance, the definition of the parameter "proportion" is “a relationship between things or parts of things with respect to comparative magnitude, quantity, or degree […] which can vary between being balanced/unbalanced”. (ferraris et al, ; gorno and colombo, ) balanced/unbalanced is a characteristic, which attributes quality to an object. that is, when looking at the proportion of an object, it is possible to state its “degree of balance”, meaning that it can be extremely balanced or extremely unbalanced or any degree in between. to clear the definition, the authors also referred to a schematic description of the concept and to some products, as in figure where there are two armchairs, the very balanced vanity fair by poltrona frau, and the very unbalanced ron arad’s big easy, by moroso. figure . proportion parameter explanation: balanced vs unbalanced the teachers are always very careful not to add any value attribution to this reading. therefore, they never say “balance is better than unbalance”, “more beautiful” or “more correct”, or anything like that. on the other hand, when possible, they point out how different proportions translate into different characters. indeed, the first armchair could be "serious and classic", while the second "funny and playful". in this first part, the authors aim at giving the students some reference points about the connection between the product form and its meaning, particularly the character. . the four approaches to form-giving the introductory lecture covers the topic of form-giving, describing two basic approaches by which designers combine shapes and lines to generate the form of objects. these approaches correspond to two opposite outputs: “primitive vs free forms” and “additive vs integral forms”. in the first case, the authors distinguish between two opposite ways to give form to objects: one is the combination of basic primitive forms, while the other is the combination of free forms and lines. the first case is that of some historical styles of the before-mentioned modernism: “the reductionist aesthetic of de stijl was characterized on the two-dimensional plane by simple geometric elements such as circles, squares, and triangles, and in the three-dimensional world by spheres, cubes, and pyramids […] the bauhaus and its successors, such as the ulm school of design and the new bauhaus in chicago, looked to this tradition, especially in their foundation courses […]” (bürdek, p. ) yet, it must be noted that, also other styles, such as art deco, used geometrical and abstract forms with a decorative purpose, visible in some noticeable examples such as chrysler building in new york. this approach to form-giving is visible even nowadays. its main characteristic is that the bi or three- dimensional primitive figures, once combined, are still recognizable in the final product. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r silvia d. ferraris, lucia rampino, venere ferraro on the contrary, in the free-form approach the object is generated from free lines and shapes without any visible geometrical scheme. again, this approach is at the basis of some important styles in the history of design, one is streamline: “developed from natural forms […] streamlining became a symbol of modernity, progress, and the expectation of a better future” (bürdek, , p. - ). the other is the “organic design” that is inspired by nature-like forms and/or principles. in the lecture, the approaches are defined through historical and contemporary examples, possibly showing two opposites in the same product category, as in the following kettles. figure . m. berntsen, quack thermos flask, georg jensen gmbh, ; aldo rossi, bollitore il conico, alessi, in the lecture, the other approach to composition refers dieter mankau’s formulation (burdek, ) of the concepts: additive, integrative, and integral forms, well expressed by the image below. the additive approach is a visible combination of different elements (in the examples: the container, the handle, the spout), while the integral one derives from the subtraction of the functions from a main figure, thus the integrative is the step in between. figure . form-giving approaches: additive, integrative, and integral forms the additive approach relates to a more functionalist approach where the parts of an object with different functions are visible and clearly added one to another. in the integrative case, the product components are perceived as distinct but integrated. in the integral approach, a basic form predominates on the functions that are cut out from it, as in the following coffee makers. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r “make it beautiful” figure . richard sapper, coban, alessi, ; luca trazzi, francis francis, lavazza, ; nescafè dolce gusto, de longhi once defined these approaches, the authors systematized them into a scheme that works like an analytical tool. the scheme combines the opposite approaches as in figure . figure . the analytical scheme with examples from the product category of table lamps the authors describe the effect of the combination of the two approaches with several examples of products. however, while the examples are perfectly corresponding to the definitions, as in figure , usually objects are not so unambiguously fitting in one single area of the scheme. that is why the scheme proved to be a very useful tool for the students to make the effort to look carefully at products’ shapes and place them correctly in the scheme. the aim is not to look for the “right” answer, which sometimes does not really exist, but rather to improve the form-analysis skills. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r silvia d. ferraris, lucia rampino, venere ferraro . the relation to the “character” the aim of the introductory lecture is to highlight the relation between form and language of the product. it points out that designers configure the form of products through different approaches and selecting several parameters so that these choices determine the overall “character” of the product. by using the concept of “character”, the authors recognize that: “people, as well as things, appear to have character -- high-level attributes that help us understand and relate to them. a character is a coherent set of characteristics and attributes that apply to appearance and behavior alike, cutting across different functions, situations and value systems--esthetical, technical, ethical--providing support for anticipation, interpretation and interaction.” (l. e. janlert et al, , p. ) thus, the ultimate purpose of the teaching activity is to let students be aware of form-character connection, pointing out that designers oversee it and, thus, they shall take it as challenge and opportunity. . the exercise brief and steps after the lecture, the students were asked to analyze and redesign a given category of products, which in / were desk accessories. each student had to pick one category of objects (i.e. calculators) to analyze it from the point of view of form and character. after the analysis, the students applied the same form-giving approach and the same character to the design of another desk accessory (i.e. a tape dispenser). in the end, the students created a group of products with the same form-giving approach and character, so that this new group has the same “family feeling”, as in the following examples. figure . desk accessories buro by lexon, desk accessories by js it is important to highlight that the exercise does not set “aesthetic rules to shape the artificial world” but sets a framework of reference. . the exercise output the first step of the exercise is an iconographic research. in this phase, students look for examples of one product (a calculator, in the following example by students menchini, raffaelli, rancan) and, then, place them in the scheme. this way, they learn to look carefully at shape, composition and details and they start to understand how complex the form-giving issue is. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r “make it beautiful” figure . scheme of the form-giving approaches afterwards, among the collected images, students choose a product they find particularly interesting and analyze it according to the form-giving approaches and the given vocabulary. in addition, they try to define the product’s character. for this last request, they do not have any specific vocabulary or tool to use; they use the words they prefer as freely as possible. in the following image, the analysis of the graphia’s calculator is displayed. in figure , it appears in the top right area of the scheme. figure . analysis of form and character of calculator s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r silvia d. ferraris, lucia rampino, venere ferraro last step is the redesign of a product featuring the character of the analyzed one. the challenge is to develop a form within very limited possibilities that derives from the previous analysis. also, the students must apply the form approach and the character without altering the archetypical function and layout of the product. figure . redesign of desk accessories with the same form-giving approach and the same character of the calculator in figure , so to make a set with the dame family feeling. the fact that clear boundaries are set for the redesign, is useful to set a path to follow. in addition, the boundaries represent a reference for the evaluation of the results, whereas an exercise of completely free form development would be less ponderable. in this context, the assessment of the results is based on the ability to reach the overall family feeling that is checked by comparison of one object to another. this way, the evaluation is not based on objective measures, but at least on a qualitative comparison. . discussion . about the exercise thanks to some years of positive experience, the author can say that the exercise proved to be useful and well structured, highly appreciated by students. yet one fault was noticed and recently corrected. in the redesign phase, indeed, some students demonstrated a tendency to follow too much the hint coming from the form and character analysis, so that they ended up designing objects impossible to use. in a way, this mistake proves that design needs to take into consideration – always and simultaneously - different aspects: form, mode of use and feasibility. thus, if “form follows function”, the result can be very poor from the aesthetical point of view, but the opposite applies as well when “function follows form”. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r “make it beautiful” to avoid this problem, teachers added the concept of the product “archetype” (ferraris et al, ) as a reference to their redesign. as heskett ( ) remarks, people have been creating ranges of suitable forms for specific purposes since antiquity. accordingly, some of these forms fit certain needs so perfectly as to become archetypal (for instance, the shape of a vase, a glass, or a fork). a form that perfectly matches a certain function is not the only reason why a formal archetype consolidates: a product’s form can also become archetypal as the result of industrial choices. this is the case with the establishment of a product’s dominant architecture. thus, all products in a given category tend to be similar: table fans, washing machines, refrigerators, televisions, and cellphones are some examples (rampino, ). students are thus asked to stay adherent to the established archetype (ferraris et al., ) in the given product category, so to guarantee an acceptable level of product usability. . about the discipline the analogy with the language proved to be useful to build a framework of reference, basic contents and analytical tools. the appreciation by the students and by the colleagues is encouraging indeed. it must be said, that two mechanical engineers are part of the teaching group of the course, and, about this exercise, they see the importance of the aesthetics matter and recognize it as central part of the design discipline. this experience let the authors think that, possibly, the designers’ inferiority complex derives from a prejudice that can be overcome through this kind of activity. likewise, the use of terms such as “beautiful” are worth using in a design school, even if a technical one, as long as they are clearly based to a framework of reference. . limits and future developments the whole discussion of the article deals with product design education at technical academia, focusing in particular on master degree – design & engineering – where students attend a very technical design course, in which the design discipline is merged with mechanical and material engineering. for this reason, the article point of view does not describe a big picture on the teaching of aesthetics in design courses, but rather covers a specific issue that might concern similar teaching contexts. the authors understand the product design field is in rapid evolution. one important change is about artifacts that are more and more embedded with sensors, electronics, processors, smart devices and smart materials. these elements make products dynamic and interactive. thus, “a domain which was once considered pure industrial design is faced with many interaction design challenges” (djajadiningrat et al, , p. ). in this perspective, the traditional design skills that focus only on physical aspects of products fall short, since they fail to address the temporal and expressive aspects of interactive behavior (gardien et al., ). indeed, the interesting field of development of design aesthetics now emerging relates to the more complex idea of “the temporal form giving” as described by valgårda et al. ( ). the exercise does not take into consideration any of these important disciplinary developments. from one side, authors believe that students should master at first the static features of products and, only after, to face more complex issues such as that of temporal form-giving of interactive products. on the other side, the idea of developing this exercise towards an aesthetic of interaction is a challenge that authors will certainly take up soon. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r silvia d. ferraris, lucia rampino, venere ferraro . conclusions this article debates on the opportunity of introducing aesthetic issues in the teaching of design at technical universities. the authors demonstrate that it is advantageous, if a framework of reference is given. they also believe education should be permeable to changes and keep evolving. for this reason, the exercise “the form of product” follows a constant development process, balancing the need to set fundamental solid knowledge with the request of updated design features. references bürdek, b. e., ( ), history, theory and practice of product design, birkhäuser, basel de mozota, b. b. ( ), design management: using design to build brand value and corporate innovation. skyhorse publishing inc. djajadiningrat, t., wensveen, s., frens, j., overbeeke, k. ( ) tangible products: redressing the balance between appearance and action. personal and ubiquitous comp. , , pp. - application of formal parameters: experience of an educational activity as part of a research project. proceedings of the rd international conference on education and new learning technologies (pp. - ). barcelona: iated ferraris s. d., ferraro. v. ( ). visual elements of products - an educational experience on "resetting and reshaping a product. proceedings of the th international conference on engineering & product desgin education (pp. - ). dublin: the design society - institution of engineering designers ferraris s. d., gorno r. ( ). expressing product character: teaching design students how to exploit form's parameters. proceedings of the th international conference on engineering and product design education (pp. - ). dublin: the design society - institution of engineering designers ferraris s. d., ferraro. v. ( ). when design innovation outdoes the archetypes. proceedings of the th international conference of education, research and innovation (pp. - ) seville: iated gardien, p., djajadiningrat, t., hummels, c., & brombacher, a. ( ). changing your hammer: the implications of paradigmatic innovation for design practice. international journal of design, ( ), - . gorno r., colombo, s. ( ), attributing intended character to products through their formal features, proceedings of the conference on designing pleasurable products and interfaces (p. ). acm heskett, j. ( ). design: a very short introduction. oxford: oxford university press. krippendorff k. ( ), the semantic turn. a new foundation for design. crc press-taylor & francis, boca raton. janlert l. e., stolterman e. ( ), the character of things, design studies, ( ), - . rampino, l. ( ). the innovation pyramid: a categorization of the innovation phenomenon in the product-design field. international journal of design, ( ), - . sudjic, d. ( ). the language of things: understanding the world of desirable objects. w.w. norton. syntax. retrived november , from http://www.merriam-webster.com/dictionary/syntax vallgårda, a., winther, m., mørch, n., vizer, e. e. ( ). temporal form in interaction design. international journal of design, ( ), - . verganti, r., ( ). design, meanings, and radical innovation: a metamodel and a research agenda. journal of product innovation management, ( ), pp. - . s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r https://en.wikipedia.org/wiki/w.w._norton https://en.wikipedia.org/wiki/w.w._norton “make it beautiful” verganti, r. ( ). design-driven innovation: changing the rules of competition by radically innovating what things mean. boston: harvard business school press. about the authors: silvia d. ferraris, phd, assistant professor in industrial design at department of design of the politecnico di milano. board member of sid (italian design society) since . her research interests focus on product design, basic design and design & engineering. lucia rampino, phd, associate professor at politecnico di milano. her research interests concern design-driven innovation processes, with a focus on interactive products. she has taken part in various research projects and serves as reviewer for both design journals and conferences. she is on the design phd faculty of politecnico di milano. venere ferraro, ph.d., assistant professor of department of design, politecnico di milano. member of the experience and interaction design research lab, she participated to several international and national researches also as coordinator. her research interest is about user centred design, interaction design and wearable technologies. acknowledgements: we would like to thank the colleagues with whom with share our courses and researches on these topics for the interesting discussions and exchanges. furthermore, we would like to thank the students who are the reason and the source of inspiration for our willingness to always improve our work. in particular, in this occasion we thank gaia menchini, davide raffaelli and giulia rancan for their contribution. s d ow nl oa de d by [ p ol it ec ni co d i m il an o b ib l] a t : n ov em be r from big screens to pasarelas: studying beauty in latin america estill, a. from big screens to pasarelas: studying beauty in latin america. latin american research review. ; ( ), pp. - . doi: https://doi.org/ . /larr. book review essay from big screens to pasarelas: studying beauty in latin america adriana estill carleton college, us aestill@carleton.edu this essay reviews the following works: making up the difference: women, beauty, and direct selling in ecuador. by erynn masi de casanova. austin: university of texas press, . pp. xix + . $ . cloth: isbn: . dolores del río: beauty in light and shade. by linda b. hall. stanford, ca: stanford university press, . pp. xvi + . $ cloth. isbn: . queen for a day: transformistas, beauty queens, and the performance of femininity in venezuela. by marcia ochoa. durham, nc: duke university press, . pp. xi + . $ . paper. isbn: . of beasts and beauty: gender, race, and identity in colombia. by michael edward stanfield. austin: university of texas press, . pp. x + . $ . cloth. isbn: . beauty and the beast. by michael taussig. chicago: university of chicago press, . pp. x + . $ . paper. isbn: . introduction in , peg zeglin brand’s edited volume beauty matters suggested the need to expand the study of beauty into a thoughtful interdisciplinarity where “kant rubs shoulders with calvin klein.” in its attention to “mat- ters” as a verb that gets at the importance but also the materiality of the workings of beauty, the collection of essays marked and measured the ongoing attempt to provide contextualized and historical studies of beauty—its value and uses, its production and mobilization, its cultural force and meaning. placing the various disciplinary voices into conversation involved moving beyond philosophy and art history, where the study of beauty had long dwelled, and looking to other fields. in the two decades prior to the publication of beauty matters, social scientists were making up time for the years they had “shunned beauty as trivial, undemocratic, and all in all not a proper subject for science.” summarizing three decades of social science research, linda jackson’s meta-analysis highlights two important findings: “democratic or not, physical attractiveness has an important influence in almost every realm of behavior,” and attractiveness still cannot be defined although it can be measured. in other words, there are measurable “attractiveness effects,” but what counts as attractive is not so easily qualified. in a similarly wide-ranging overview of the semiotics of beauty, sociologist anthony synnott reviews the history of the trope that beauty equals goodness and then peg zeglin brand, introduction to beauty matters, ed. peg zeglin brand (bloomington: indiana university press, ), . the book title invokes influential texts like judith butler’s bodies that matter and cornel west’s race matters. nancy etcoff, survival of the prettiest: the science of beauty (new york: anchor books, ), . etcoff compares the late entry to the topic of social scientists to the long-standing attempts of philosophers and artists to qualify and quantify the nature of beauty. linda a. jackson, physical appearance and gender: sociobiological and sociocultural perspectives (albany, ny: suny press, ), . https://doi.org/ . /larr. mailto:aestill@carleton.edu from big screens to pasarelas considers the modern symbolic values of beauty: as status symbol, genetic luck, aesthetic goal, and social power. in the s and s, feminism fueled studies of beauty that sought to understand how it served as a tool of oppression, made powerfully dominant through patriarchal and capitalist circuits of meaning. many of these texts had activist leanings as they hoped to recuperate individual agency within heavyweight cultural forces. while this groundwork produced a steady stream of interest and engagement with studies of beauty in us academia, no comparable turn toward beauty happened in latin american studies. the texts reviewed here are a welcome addition to the field and will hopefully lead to further research in their various fields and national contexts. two are ethnographies that develop their analyses from substantial interviews, sur- veys, and participant observation. erynn masi de casanova’s making up the difference examines women’s labor within a cosmetics direct selling organization; she considers the way in which the cosmetics company and the kind of beauty that it sells shapes sellers’ and buyers’ home and work relationships. marcia ochoa’s queen for a day provides detailed insight into how beauty and glamour are invoked to structure feminin- ity for transgender individuals and beauty queen participants; their ongoing juxtaposition lays bare the constructed and yet materially vital performance of femininity. two of the books reviewed are histories. in dolores del río, linda hall marshals an impressively extensive archive in order to puzzle together a compel- ling story of the film star’s life, with a particular focus on considering how del río’s beauty contributed to her success. michael edward stanfield covers more than one hundred years of colombian history in of beasts and beauty. depending principally on an archive of popular magazines, he points to the important role that beauty pageants have filled by exemplifying and symbolizing order, purity, and morality in the face of the economic, social, and physical violence of the nation-state. finally, anthropologist michael taussig offers a series of thought-provoking meditations on scenes from his fieldwork in colombia. theoretically and narratively beguiling—indeed, posed within the frame of the fairy tale—taussig’s work urges us to con- sider how beauty is produced in tandem with the economic devastation, agricultural exploitation, and rav- ages of the nation’s long civil war. attentive to the specifics of latin american history, politics, economics, and culture, together these texts build on—explicitly or implicitly—the questions and themes that have come to contour the study of beauty in general. these include the gendered workings of beauty; how beauty is understood at the intersection of self and society through the concept of body work; how beauty is performed and staged; the role that beauty plays in developing national identities and its relationship to modernity and social values; how the flip side of beauty—the ugly, the infirm, the racially marked—produces values and ideals as well. gender matters in order to study the production of beauty, scholars have found it to be essential groundwork to consider the asymmetrical use of “beauty” as a meaningful category. as john berger’s ways of seeing establishes, “men act and women appear. men look at women. women watch themselves being looked at.” each of these texts establishes beauty’s attachment to and production through femininity (and attends to how masculinity rejects or has little need of discourses of beauty), examining how beauty values and expectations are unequally tethered to the cis-female body. yet the scholars vary in their calibration of the nuances of gender and beauty. arguably proffering the most nuanced definitions because of her field of study, marcia ochoa’s ethnography strives to consider how the “accomplishment of femininity” works within both transgender communities (transformistas) and cisgender beauty pageants (misses) in venezuela. explicit in ochoa’s anthony synnott, “truth and goodness, mirrors and masks—part i: a sociology of beauty and the face,” british journal of sociology , no. ( ): – . particularly influential were susan brownmiller, femininity (new york: linden press, ); wendy chapkis, beauty secrets: women and the politics of appearance (boston: south end press, ); nancy friday, the power of beauty (new york: harpercollins ); robin t. lakoff and raquel l. scherr, face value: the politics of beauty (new york: routledge and kegan paul, ); and naomi wolf, the beauty myth (new york: anchor books, ). there are a few exceptions, although most published within the last ten years: colleen ballerino cohen, richard wilk, and beverly stoeltzje’s edited volume beauty queens on the global stage: gender, contests, and power (new york: routledge, ) includes one essay on guatemala and one on nicaragua. also see alexander edmonds, pretty modern: beauty, sex, and plastic surgery in brazil (durham, nc: duke university press, ). literary critic elizabeth gackstetter nichols’s work includes “decent girls with good hair: beauty, morality and race in venezuela,” feminist theory , no. ( ): – , doi: https://doi.org/ . / ; and beauty, virtue, power, and success in venezuela, – (lanham, md: lexington, ). also see medical anthropologist lauren gulbas’s work, “embodying racism: race, rhinoplasty, and self-esteem in venezuela,” qualitative health research , no. ( ): – , doi: https://doi.org/ . / . john berger, ways of seeing (london: bbc and penguin books, ), . the phrase is one that ochoa takes from harold garfinkel’s work; see studies in ethnomethodology (new york: prentice-hall, ). https://doi.org/ . / https://doi.org/ . / estill framing is that the fashioning of gender must be understood through the unexpected comparison that points out the similarity of tools used by transformistas and misses and how these groups “create possibili- ties for themselves through beauty and glamour,” even if these possibilities yield vastly different results. for the misses, these constructions and performances lead to a success on the runway that is not necessarily marked by submission to a dominant beauty ideal but rather by agency and control of one’s self-image. for the transformistas, a highly self-referential and self-conscious performance of femininity is needed to “call attention to the contradictions surrounding their presence on the avenida” ( ). ochoa’s ethnography reveals the fungibility of femininity, and how beauty values serve to reinforce and establish it. to some degree, casanova’s work reveals a similar approach to gender. her work relies on ecuadorean demographic data that documents differences between men and women’s economic participation in the labor force; this data leads to a fairly traditional social understanding of gender and ideals of heteronormativity, traditional family structures, and cis-women’s restricted social roles. challenging these normative understandings, however, her study of yanbal, a direct selling cosmetics company, allows her to examine women as workers within a company that sells traditional ideas of femininity and its relationship to beauty even as the executives and sales force struggle against these gendered norms. she highlights “moments of empowerment”—occasions when “constraints of traditional gender roles are temporarily lifted” ( ). hall’s biography thoughtfully locates dolores del río within both mexican and us gendered norms of the time period, acknowledging that because of her power and fame del río “was able to engage in behaviors not initially acceptable for young women of her social class in mexico” ( ). hall asserts that del río’s beauty was key to her success, enabling hollywood (and the united states) to overlook her mexicanness. for hall, then, del río’s beauty—perceived as feminine and exotic—served as a primary and principal source of power as it provided access to career, marriage, and a sort of independence, all of which were unavailable to most women of the period. stanfield similarly establishes that, for the long-term historical view that he takes, beauty is women’s singular power in a world in which they have not much else. colombians value beauty, he suggests, because “the terror of the beast—violence, insecurity, racism, poverty, and the perceived illegiti- macy or inadequacy of government—reinforces gender roles (women should be beautiful and men should be powerful) as it closes options for reform and liberation” ( ). while hall is interested in how del río lever- ages this gendered power for her own means, stanfield asks us to consider how beauty, as a gendered power, is produced in antithesis to and in the service of “the beast,” always and already a conservative force. within this framework, femininity is a fairly static characteristic, even as expectations for beauty sometimes shift. while michael taussig’s beauty and the beast also begins from the premise that to understand colombia it is necessary to think about both the beast and the beauty, he emphasizes that glamour and terror operate synergistically. in working through the “cosmic surgery”—the profusion of manipulations of bodies in order to survive—he suggests that “aesthetics is as crucial to the tough guys and the state as it is to bigger breasts, face lifts, or willowy thinness” (ix). of the five authors reviewed here, taussig deconstructs most fully the inadequate binaries that link beauty’s demands with cis-female bodies. he calls our attention to the excess (dépense, georges bataille’s term for “too-muchness,” p. ) and luxury that suffuse and produce contem- porary aesthetics, whether “designing a new body, a new face, a smile for a paramilitary mass murderer, an airplane, a spark plug . . .” ( ). beauty, says taussig, is infrastructure for all of these even though most of us perceive it solely as ornament. between self and society because beauty is profoundly gendered as female—though not inevitably or naturally so, as ochoa’s and taussig’s work make clear—a dominant approach to understanding the production of beauty values through feminized bodies acknowledges that body work (those practices undertaken to match one’s self to one’s body, or one’s body to social expectations) occurs at the individual level but is only made coherent at the societal level. while early scholarship in the field presumed that body work was undertaken subconsciously and through engagement and submission to oppressive discourses, contemporary scholars generally reject the “cultural dope” model and seek to understand individual motivation, involvement, and pleasure in body work within a framework of recognizing the social, cultural, and economic rewards of doing body work readings like these—see susan bordo, unbearable weight: feminism, western culture, and the body (berkeley: university of california press, ) for one of the classic texts in the field—rely on connecting feminism’s critiques of patriarchal structures with foucault’s work on docile bodies and micropractices, the combination yielding a theoretical framework for understanding the intersection between individual engagement and social discourse in a set of practices to discipline the body in order to achieve acceptable femininity and beauty. from big screens to pasarelas effectively. both ethnographies (casanova and ochoa) have at their core the aim to locate individual moti- vations and meaning-making within larger social structures in order to understand better how women and men engage with structures of femininity and beauty. hall’s biography is deeply invested in understanding dolores del río as an individual with personal agency, caught within a star system and a bicultural set of expectations. stanfield and taussig, on the other hand, are more invested in sweeping landscapes of beauty’s operations; glimpses of individuals disappear within the comprehensive narratives that each proffers of colombian beauty politics. hall struggles to understand dolores del río beyond the cultural dope model, but her attempts are often frustrated by the lack of archival evidence. placing del río’s quest for beautification within the context of hollywood and its demands, hall narrates del río’s whitening and presumed cosmetic surgery not princi- pally through del río’s records (because there is not much there) but through what we know of her cohort and their own need to beautify in particular ways in order to be successful. indeed, while hall focuses on bet- ter describing del río’s quest for love and economic success (both journeys that often involve, hall suggests, the trade of beauty for stability or comfort or power), she also offers insight into the female friendships—in hollywood and in mexico—that were so formative and important to del río. these glimpses of formative female support networks help hall make the case that gender is produced within larger social systems that contain the possibility of acquiescence (the suggestion that del río had her nose done like other hollywood stars of the period) or of resistance (the limning of del río’s friendships with frida kahlo and tina modotti as providing her support against the establishment). both casanova’s and ochoa’s work, dependent on extensive fieldwork and interviews, place great impor- tance in understanding how their subjects understand their own body work. in the case of ochoa’s work, this allows her to delineate the common ground shared by transformistas and misses, both groups engaged in processes by which they can “sacar el cuerpo” (bring out the body), a phrase that, ochoa argues, demon- strates the “active participation of transformistas and misses in producing their feminine bodies” ( ). both ochoa and casanova find it necessary to understand these bodies in place, something that casanova dis- cusses beautifully as a way to understand “the places that people hold within webs of social connection that span and sometimes overrun the space of the city” (xi). casanova’s work adds a great deal to our thinking about agency with regard to beauty politics, since the direct selling group yanbal is mainly run by women. she situates her study in relationship to a lack of literature on direct selling organizations (dsos) and, in particular, ethnographic data that help us understand the everyday lives and perspectives of distributors. for beauty scholars this is helpful because the understanding of women as only consumers is a dominant one. within guayaquil, casanova’s work reveals, women distributors are also positioned as informed consumers well able to shape economic processes, if not the beauty norms themselves. within the dso world of yanbal, the selling of beauty provides idealized images but also accessible models of what it means to look “bien arreglada”; but, casanova emphasizes, to not achieve this look and do this body work means to be seen as a body that has no social mobility. the stage and the spectacular scholars of beauty often point out that individual body work need only offer access to “the average”; that is, in order to be perceived as attractive, one must simply demonstrate that one has the time, energy, and money to do body work. casanova’s finding on the importance of appearing “bien arreglada” reinforces this point. yet beyond the everyday workings of beauty, scholars continue to focus on beauty pageants, film glamour, and other “spectacular” productions of beauty because those images and processes wield great power, particularly in the development of regional and national identities, as examined in the next section. for hall, the question of the spectacular and the performative are particularly troublesome because of her investment in ensuring that she portrays del río with both “agency and humanity,” countering the “con- structed image” and star text that are a product of the spectacular ( ). yet challenging the constructed image proves to be complicated and even impossible given the archive, as hall details throughout the biography, culminating in the chapter “icon” as she discusses the easy way in which mexicans, like us americans, “con- flate[] the woman with the actress and her roles” ( ). debra gimlin, body work: beauty and self-image in american culture (berkeley: university of california press, ). for the debate over women as cultural dopes in these beauty processes, see the introduction to kathy davis, dubious equalities and embodied differences: cultural studies on cosmetic surgery (lanham, md: rowman and littlefield, ). estill in contrast, ochoa engages the spectacular as a way to understand—at a number of different “politics of scale”—the production of femininity and beauty. in the first part of her book she looks at the way in which the transnational circuits of beauty pageants provide a stage on which national beauty politics are performed. the second section “describes a scenic scale in which women are staged,” comparing cis-gender pageants with those targeted for transformistas and gay men as well as how sex work on avenida libertador in caracas operates as a stage too. in her final section she considers the relationship between the spectacle of femininity and that of venezuelan politics. stanfield’s wide-ranging field finds its center in working through the play between colombian politics and colombian beauty pageants. while stanfield doesn’t place much emphasis on the theory behind the rel- evance of the beauty pageant and its staging of national identity and values, his topic reveals the importance of the performative. it would be worthwhile to build on his research by thinking through the gendered per- formances that lead to the binaries that he sees, where masculinity and the state offer chaos and violence, and femininity and beauty provide morality, civility, and hope. using a lens of performance theory places stanfield and taussig into greater conversation with each other, even though neither uses this vocabulary. instead, taussig uses the language of “cosmic” surgery and the fairy tale narrative. these are alternative ways of thinking through the desires that inform cosmetic surgery—the hope that we can “create a new inside by changing the outside,” that is, we can stage our bodies into a new understanding of self ( ). taussig’s work illuminates how cosmic surgery may be most visible to us at the individual level, but, as he puts it, “the state itself has existed as an exercise in extreme makeover” ( ). making up the nation as the quote from taussig makes clear, the workings of beauty, visible in and on individuals, take on spec- tacular visibility and then national significance. echoing mimi thi nguyen’s recent challenge that we think of beauty as one of the “transactional categories that are necessarily implicated and negotiated in relation to national and transnational contests of meaning and power,” each of the texts under review here tracks the workings of beauty as a measure of progress, modernity, and democracy. each of these monographs power- fully situates and is attentive to how the workings of beauty contribute to nation construction. hall situates del río within both mexico and the united states, asking why the movie star had binational and bicultural appeal; in both countries she experienced moments of enormous cultural power as well as repercussions for her fame. ochoa situates the transformistas and misses carefully within venezuelan history, place, and politics. casanova does the same with yanbal, making sure to specify not just ecuadorian economics but also its geographical and historical particulars. taussig’s and stanfield’s use of the “beauty and beast” fairy tale might seem to argue for universal implications in their understandings of beauty, but both anchor that fairy tale within colombia proper. in his introduction, stanfield poses the question in a larger way: “how and why has beauty in modern american republics reinforced notions of development, modernity, and a white pigmentocracy inherited from european colonialism over the last half millennium?” ( ). for stanfield, as for taussig, the “beast” is the nation-state in disarray: questions of illegitimate statehood, violence and insurgency, narcotraficantes. for taussig, it is also a shift from locally based agricultural production to major agribusiness interests. each of them suggests—in works that came out nigh simultaneously—that the valuation of feminine beauty was a necessary and dysfunctional partner to the beast. while for stanfield beauty stands as a beacon of goodness in contrast to the frequent violence of the state, taussig sees the two stitched together in terms of modernity and its relationship to consumption and the makeover. in similar contrast, while taussig focuses on cultural narratives that insistently stare at the synergism of “glamor and terror” (ix) and wonders why we are fascinated by stories of beautification and makeovers gone wrong, stanfield’s history provides a straightforward albeit greatly compressed overview of “the social, cul- tural, and political importance of feminine beauty in colombia from to ” ( ). acknowledging the unwieldiness of his scope, stanfield emulates the breadth and approach of lois banner’s groundbreaking study of us beauty that likewise attempts to outline the beauty politics of one country. like banner’s classic for fleshed out theorization of the relationships of pageants to nationality and nationalism, see sarah banet-weiser’s the most beautiful girl in the world: beauty pageants and national identity (berkeley: university of california press, ), and colleen ballerino cohen, richard wilk, and beverly stoeltje, eds., beauty queens on the global stage: gender, contests, and power (new york: routledge, ). mimi thi nguyen, “the biopower of beauty: humanitarian imperialisms and global feminisms in an age of terror,” signs , no. ( ): . from big screens to pasarelas text, this book provides grand overviews that will be increasingly useful for scholars who follow as they fill in the gaps. and in a study with an ambition this large, it should be no surprise that there are gaps. stanfield sees beauty as representing “the feminine and social constant opposite institutional, elitist, dysfunctional, and often violent male order/chaos” ( ). this frame imposes a fairly essentialist gendered reading—unlike taussig’s analysis of the cooperative and intertwined functions of violence and beauty—that fails to nuance the conceptualization or the workings of beauty as thoroughly as it could. part of this stems from a gap in stanfield’s literature review, which omits scholarship on the united states that could have been useful to his work on race and beauty in colombia. in a study that focuses mainly on tracking the understanding, reception of, and meaning of beauty pageants in colombia (contextualizing these for each historical period), stanfield is aware of, but makes scant use of, formative works in the field, citing them but not engaging with their analyses of the nationalistic and decolonial projects in which beauty pageants often engage. given stanfield’s overarching claim that, in colombia, beauty “is feminine, moral, virtuous, civil, uplift- ing, peaceful, and hopeful” in contrast to the chaos and violence of masculine rule, it follows that beauty pageants are insistently posited as antidotes and/or alternatives, in spite of the fact that stanfield’s use of the colombian periodical cromos (his principal, and longitudinal, primary source) shows that the business of nation building and the work of beauty culture were deeply intertwined. building his findings primarily on periodical sources for each period of time, stanfield offers a detail-filled and copious narrative that would be more powerfully instructive if theorized more consistently. for example, as he traces the rise of consumer culture, he might have engaged with histories of gender and consumer culture or theories of gender-segmented marketing. while stanfield examines the historical development of beauty pageants, ochoa uses the venezuelan beauty pageant to better understand how beauty and glamour work for both beauty queens and transgen- der women as a set of symbolic resources that articulate venezuelan femininity. at its heart, ochoa’s monograph asks us to consider the constructedness of femininity and, in thinking through how transgender women evoke and use it, to see its connections to the policing of gender and social violence against those who do not fit its demands. ochoa describes persuasively why her attention to venezuelan femininity is best understood through critical frameworks of queer sexuality, transnationalism, and diaspora. her intro- duction richly and fully describes her engagement with these fields in order to arrive at her framework. while her narrative is often dense, the prose is also deeply engaging and warm. as befits an ethnographer, ochoa places herself carefully and gracefully within her fieldwork. she does not hold back from large claims that require paradigm shifts: “the process of modernity extinguishes humanity yet creates possibilities for existence. this contradiction frames the long project of modernity in latin america” ( ). in extending this contradiction, ochoa places her monograph in conversation with a number of scholars of beauty who, in other spheres, contend with the way beauty has been wielded as a presumptively modernizing and coloniz- ing force. divided into three principal parts, ochoa’s text begins at the global scale, examining the transnational cir- cuits in which she understands the venezuelan beauty pageant (thus contextualizing in a way that stanfield does not) and considering how transgender identity in venezuela is produced in relationship to interna- tional, cosmopolitan ideals. ochoa suggests that glamour “allows its practitioners to draw down extralocal authority, to conjure a contingent space of being and belonging” ( ). in this formulation, transformistas’ embrace of an aesthetic of glamour channels transnational meanings. next she moves to a local scale, juxta- posing the beauty pageant runway (in all its forms—from the regional to the transformista) and transform- istas’ sex work on avenida libertador in order to consider the public staging of femininity. her third section lois w. banner, american beauty: a social history…through two centuries…of the american idea, ideal, and image of the beautiful woman (new york: knopf, ). stanfield points to an absence of us histories on beauty except for banner’s work, strangely overlooking kathy peiss’s impressive and thorough hope in a jar on the history of cosmetics in the united states as well as julie willett’s work on beauty salons, elizabeth haiken’s history of cosmetic surgery, and maxine leeds craig’s history of black women and beauty pageants in the united states. he cites both banet-weiser’s the most beautiful girl in the world and cohen, wilk, and stoeltzje’s beauty queens on the global stage. for example, joanne hershfield’s imagining la chica moderna: women, nation, and visual culture in mexico, – (durham, nc: duke university press, ). nguyen, “the biopower of beauty”; margaret hunter, “buying racial capital: skin-bleaching and cosmetic surgery in a globalized world,” journal of pan-african studies , no. ( ): – ; kathy peiss, “educating the eye of the beholder: american cosmetics abroad,” daedalus , no. ( ): – . estill drills down to the body, examining in detail what it takes to accomplish femininity (to “sacar el cuerpo”). ochoa powerfully connects analytically the bodies of the misses (pageant contestants) and the transformis- tas, showing how both groups—on the surface different—engage similarly in the art of the spectacle to stage femininity and beauty. announcing her work as a queer diasporic ethnography, ochoa situates herself as field worker and scholar within a well-fleshed-out theoretical frame that still manages to be intensely introspective and intimate. in one breath she lets us into her history and family; with the next she invites the reader to consider the perverse modernity that requires and makes possible malleable bodies, and that requires the violence we do to our bodies that also makes possible their survival. as ochoa says, venezuela herself is a transformista. in this metaphor, ochoa argues that beauty and glamour and feminine makings are not frivolous; rather, they structure national narratives. similarly attentive to the violence required by modernity that produces nationally legible bodies and beauties, taussig’s work suggests that colombia, like many other sites, is now home to the postmodern con- sumer who has a “norm-defying and norm-transcending body” ( ). he anchors this particular postmodern body within colombia’s agribusiness, narco-business, and in general the speedy change from rural to urban- centered lives. taussig is curious about how the shift away from the land, from caring for the land, produces an excess of attention and care to the new generations “who carry this new history on their bodies” ( ). for taussig, then, national imaginings are related to how individuals understand their bodies as productive or consuming tools. while focused on colombia’s particulars, taussig does not ignore the ways in which colombia’s beautify- ing culture operates in relationship to other latin american countries like brazil or venezuela, as well as within postcolonial and imperial relationships like the one between the united states and latin america. for example, pointing out that “the new thinness amount[s] to an imitation of what we might call the white body,” taussig also underscores the way the “afro-inspired pompi” continues to matter; the colombian (national) body is a site where beauty operates with racial and economic codes. similarly attentive to transnational and imperial dynamics, hall’s del río navigates beauty ideals in mexico and the united states, revealing the differences in gender nationalisms as well as the ways in which del río’s racialized body does or does not affect the degree to which hollywood can imagine and desire a “dark female lover.” hall’s work is not entirely consistent on the role that race plays. for example, hall touches on a number of ways in which del río’s beauty presented difficulties for us filmmakers and audiences, principally issues of color and the relationship of these to social status and class. however, hall hesitates to confirm the connection between these social structures and the beauty work that del río did or the way in which her beauty was perceived, in part because while she traces evidence of del río’s whitening, she places this in relationship to the publicists’ continuing presentation of del río as latina/mexican. thus, for hall, this whitening has little to do with deracialization. as she says, “it seems reasonable to suggest that the ideals of beauty that were developing in hollywood . . . were exotic foreigners with slender noses” ( ). hall’s resistance to acknowledging forces of racialization seems to stem from her understandable desire to establish del río’s individuality and agency. hall reads beauty as power that establishes del río’s success in film and in her personal life. for example, when she provides an overview of del río’s love life in her early forties, she remarks, “one of the world’s most beautiful women, the object of fantasy for men all over the globe, was still alone” ( ). this framing reveals hall’s conceptualization of beauty as a power that only wanes with aging, and it is a frame that is ultimately inadequate, whether to understand del río or to better understand how beauty works and is used. hall’s text is full of the equivocations of someone working around absences in the historical record and attempting to make sense of these gaps: why did del río’s early relationships fail? how did she negotiate being a foreigner in the unites states? if, as hall argues, del río’s billing as “the perfect latin type” estab- lished “a more inclusive definition of just who might be considered white,” how did del río feel about this sublimation or reframing of mexicanness? the gaps are unavoidable, given the limited material available to work with, and hall certainly creates an engaging and full narrative that makes the book enjoyable to read. however, more insistent attention to the national and transnational beauty politics that at times cir- cumscribed del río’s possibilities, and at others accentuated them and made her a more viable commodity, would have provided more persuasive accountings of her life. while the transnational meanings of racialized beauty are not fully fleshed out, hall’s study shines when it comes to depicting how del río and hollywood used her beauty over the course of her career. hall sug- gests that, for del río, beauty operates as a given—a gift that del río was granted of a particular legible from big screens to pasarelas attractiveness—but also as a set of practices (cosmetics, fashion, poses) that del río used, whether instinc- tively or knowingly, in order to produce and market her beauty. the biography offers a thorough depiction of the kinds of body work available and needed in hollywood and then, importantly and thoughtfully, reveals how the older del río was almost too beautiful to play the roles she received in mexico. casanova’s ethnography immerses the reader within a case study of yanbal, ecuador’s largest direct selling cosmetics company, as a way to understand gendered labor, social, and economic relations and, importantly, how the nature of yanbal’s business (beauty culture) affects these issues. situating yanbal and its business structure within the contemporary ecuadorian economic and political context, casanova points out how the loss of employment in the formal sector and the rise of underemployment in ecuador make research on dsos essential. given the paucity of work on the intersection of gender and dsos, casanova establishes a useful baseline for understanding why dsos provide a good case study for thinking about gendered labor: operating as part of the informal job sector, dsos’s employee rosters are predominantly women. the job features high flexibility, theoretically making it a useful job for women coping with juggling with the triple burden of work, home, and community service responsibilities ( ). casanova particularly focuses on the “everyday lives and perspectives of distributors” as well as the transactions between sellers and consumers. for scholars of beauty, casanova’s second section is most relevant. after explaining how yanbal fits into gendered labor and familial structures, she explores and analyzes the image provided within yanbal’s promotional and sales materials as well as within and through training for sales people. yanbal can be under- stood as a microcosm for the nation, offering insight into how the politics of appearance for sellers (being “bien arreglada”) reflects larger discourses of social class and racial belonging. because the “flexibilization” of labor that occurs within capitalist globalization ( ) still relies on the instantiation of traditional gender roles, whether at work or at home, casanova’s analysis of how women negotiate greater economic independ- ence with and through continuing to mold their bodies to traditional feminine standards provides a great deal of insight into the limits of empowerment discourses when it comes to women’s labor, and how that empowerment is understood through materialized body and beauty norms. indeed, as she discusses in her thorough content analysis of yanbal catalogs, “glamorous images on its pages strengthen their claims to a professional identity and an enviable association with a respected transnational corporation” ( ). put dif- ferently, the catalogs aren’t just selling the product and ideals of femininity, motherhood, and whiteness to the consumer, they’re selling the seller as a worldly and cosmopolitan worker. casanova details effectively the many tensions that the women she interviews experience and in particular how “the cultural valua- tion of whiteness and upper-class status is juxtaposed with the phenotypic and financial realities of most ecuadorians” (xiv). on the outskirts if beauty operates to produce the conditions and visible connections of national belonging, it is also per- sistently in relation to other aesthetic possibilities—ugliness, violence, the grotesque—that repel one from belonging. taussig’s focus on the aesthetic of both violence and embodiment allows him to ask what para- military armor and masculinized bodies or women with enhanced breasts and butts “tell us about the new body set forth in the world today” and “its relation to storytelling” ( ). in staging his intervention into colombian violence and beauty politics as a theoretical engagement invested in storytelling, taussig sifts through the conditions that have shaped the body into an “emblem and vehicle for a way of being that has displaced work and discipline in favor of style, transgression, and eroticized excess” (x). working with a number of western cultural theorists from freud to benjamin to bataille’s notion of dépense (wasting/excess/unproductive spending), taussig’s analysis culminates by engaging zygmunt bauman’s distinction between the modern producing body and the postmodern consumer body. the latter body, in bauman’s work, is “norm-defying and norm-transcending”; taussig argues that his history of beauty is a “history of norm-defiance and norm-transcendence . . . fashion as a new way of life oriented toward death” ( ). in offering this historical narrative, taussig argues for a need to recognize the alienation of the body from its labor and its environment as one of the important factors in better understanding the relationship between beauty and ugliness. for him, in the industrialized world with its unthinking progress, “beauty lives side by side with murder and mutilation and is exacerbated by this ugliness” ( ). taussig’s work echoes nguyen’s recent work on the biopower of beauty. analyzing the kabul beauty school, nguyen points out that in global “geopolitical contexts of neoliberalism and human rights” beauty operates as a transactional category ( ). what she means by this is that beauty is offered and understood estill as a promise—a promise of personhood, rights, and good governance. nguyen sees how beauty has been wielded as a good held by westerners that can be offered to “deserving” nations in the context of empire and war. in this instance, afghani women’s potential beauty stands as a symbol of a nation’s worthiness to be free and autonomous. beauty operates, then, as a violence itself, a technology that demands acquiescence of a body or bodies in order for them to be considered worthy. taussig sees a similar merging of beauty, violence, and death, arguing, insistently and firmly, that “the realm of the aesthetic embraces bodily mutila- tions by paramilitaries alongside agribusiness mutilations of our mother the earth” ( ). in other words, taussig uses his fascination with these stories of excess, taboo, and the malleable bodies of postmodern consumer society to delineate the relationship between beauty politics and violence in a contemporary colombia caught between a masculine narco-culture, the rise of agribusiness, and the ongoing quest for aesthetic control and satisfaction. in the other texts, ugliness sits unfortunately in more expected places: the residues of colonialism and slavery materialized through hierarchies of race and class. stanfield begins his book by highlighting the uneven workings of race and beauty in colombia and he provides examples that portray the dominance of whiteness as a beauty value while also offering moments when racialized beauty becomes the object of consideration and negotiation (including stories of tensions between official pageant officials and the com- munities that support particular candidates). stanfield’s narrative in this area does beg for more analysis and further research of how race or racism operates in colombia. for example, in his chapter on the s, stanfield points to the señorita colombia pageant as one that took place indoors at a site where “two hundred years earlier, slaves had been bought and sold” ( ); two pages later, he reveals that the pageant (miss universe) “broke the color barrier” ( ). these facts sit in tension with the acknowledgement that colombia “would not select its first black señorita colombia until ” ( ), but there is no narrative that helps the reader see how beauty politics highlight and reveal a deeper, historically sedimented racial hierarchy and why, in , that racial hierarchy saw a breach. for casanova and hall, there are prices to pay for not being white enough and not being “bien arreglada” enough. hall narrates how del río’s foreignness (and her racial not-white-enoughness) ended her career as hollywood fashions shifted and she aged. casanova details how yanbal sellers and their superiors discipline each other’s appearances in order to measure commitment to their work. in other words, if taking care of oneself with these products that “have a global cosmopolitan stamp” indicates a particular adaptation to social status and cultural norms of appearance “that are ultimately local,” not taking care of oneself in these expected ways removes you from being perceived as having ecuadorian middle-class respectability ( ). examining how beauty produces belonging and citizenship, each scholar also contends with how the spe- cific operations of beauty depend on the production of ugliness, and how this ugliness, unlike the human- izing power of beauty, expels one from community. because ugliness, like beauty, is socially constructed, each scholar, in their attention to the specifics of beauty, must be equally precise in how ugliness manifests, whether through systems of race, class, or cisgender norms. attendant to the potential of these forms of ugliness to expel one from belonging, whether from domesticity, ideals of femininity, ethnic and racial community, or nation, these scholars analyze “how people shape their looks and make up their faces to move with grace through these many spaces of their lives.” moving with grace, with culturally legible beauty, is easier for some than for others. adding to the growing scholarship in this area, these monographs acknowledge and carefully unpack these hierarchies and how they restrict or permit access to the beautiful. author information adriana estill is associate professor of american studies and english at carleton college. she researches and teaches primarily in latina/latino studies, with interests in the textual and visual production of meaning around race, gender, and place. she has published articles that look at how beauty serves as a rubric of mean- ing and a tool of belonging within national narratives; how resistance and belonging to place are gendered; and the ways that the mass media imagines raced communities in relationship to whiteness. she is currently working on research that traces the circulation of the telenovela on american television, examining the genre’s use, reception, and misreadings by the white american public. nguyen, “the biopower of beauty.” susan ossman, three faces of beauty: casablanca, paris, cairo (durham, nc: duke university press, ), . from big screens to pasarelas how to cite this article: estill, a. from big screens to pasarelas: studying beauty in latin america. latin american research review. ; ( ), pp. - . doi: https://doi.org/ . /larr. submitted: august accepted: august published: july copyright: © the author(s). this is an open-access article distributed under the terms of the creative commons attribution . international license (cc-by . ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. see http://creativecommons.org/ licenses/by/ . /. open access latin american research review is a peer-reviewed open access journal published by the latin american studies association. https://doi.org/ . /larr. http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / introduction gender matters between self and society the stage and the spectacular making up the nation on the outskirts author information reviews denis dutton. the art instinct: beauty, pleasure, and human evolution. new york: bloomsbury press, , pp. isbn - - - - the art instinct is a terrific book and it is a great loss that denis dutton, an american philosopher of art who taught at new zealand, passed away less than a year after its publication. the book belongs to a string of recent publications that promote a naturalistic – specifically, darwinian – refashioning of topics traditionally treated in the humanities in lofty isolation from the sciences of nature: politics, morals, religion, and art. the art instinct differs from these other books. on the one hand, some of the most famous of them, such as steven pinker’s how the mind works ( ) and the blank slate ( ), and edward o. wilson’s consilience ( ), consider art and aesthetics only in passing and what they say about these topics is not flattering. on the other hand, there are scholarly books specifically on matters of darwinian aesthetics, such as homo aestheticus ( ) by ellen dissanayake and the literary animal ( ) edited by jonathan gottschall and david sloan wilson, but their impact has remained largely confined to academic circles. dutton is now as big on the market of popular books on the new evolutionary humanities as pinker or e. o. wilson but, unlike them, dutton was a trained philosopher who succeeded in bringing the darwinian approach to bear on the key issues in the philosophy of art in a manner attractive to the educated layman. unlike other reviewers that i have read, i should like to highlight dutton’s principal theoretical contentions by contrasting his approach with that of a leading contemporary philosopher of art, arthur c. danto. dutton himself engages danto on a number of points, and while the art instinct offers perceptive criticisms of other past aestheticians – including kant – i believe that the novelty of dutton’s program is best seen when compared with a contemporary theory, rather than a theory from the distant past. and, after all, danto’s type of theory has also been quite influential during the last two decades in central europe, so it provides a useful backdrop for a local reader as well. the first point at which dutton departs from danto is in downplaying the issue of the definition of art. the development of post-world war ii academic aesthetics may be seen in terms of the rehabilitation of this key concern of the classic philosophy of art. in the s, many philosophers, under the influence of the later wittgenstein, convinced themselves that the project of defining the concept of art is hopeless. art is just too multifarious, lacking in any essence, so that all the things and activities that fall under this concept share nothing but estetika: the central european journal of aesthetics, xlviii/iv, , no. , – of mice and men: adorno on art and the suffering of animals zlom _ . . : stránka ‘family resemblances’. in his the transfiguration of the commonplace ( ) and elsewhere, danto famously charged that the failure of wittgensteinian aesthetics to supply a definition of art was caused by its assumption that any such definition could feature only the perceptual properties of candidate objects and activities. according to danto, all the works of art, no matter what they look like, share certain conceptual features: they are all representations of a certain very special sort. we can leave the details of danto’s definition aside, although it was precisely the disagreements about those details that propelled much of the discussion in philosophy of art since the s. in dutton’s view, the prioritization of definition is motivated by a misguided choice of samples. danto and his followers concentrate on highly refined, avant-garde artworks, such as duchamp’s fountain and warhol’s brillo boxes that appear indistinguishable from ordinary objects. it is precisely due to this perceptual indiscernibility that danto rejects the perceptual properties of candidate artworks as their art-making properties. for dutton, this conclusion constitutes a reductio of this elitist, manhattan-centered view of art. art includes much more than the items on display at moma or the leo castelli gallery. art is everywhere, and has been throughout the history of our species. we may never know its exact origins, but the practice of art-making goes back tens of thousands of years at least. given that the artistic output of cultures distant in both time and place is now more available to us than ever before, the concentration of recent aesthetics on marginal cases is almost paradoxical. we can study and enjoy sculptures and paintings from the paleolithic, music from everywhere, folk and ritual arts from all over the globe, literatures and visual arts of every nation, past and present. against this glorious availability, how odd that philosophical speculation about art has been inclined to endless analysis of an infinitesimally small class of cases, prominently featuring duchamp’s readymades or boundary-testing objects such as sherrie levine’s appropriated photographs and john cage’s ’ “. underlying this philosophical direction is a hidden presupposition that is never articulated: the world of art, it is supposed, will at last be understood once we are able to explain art’s most marginal or difficult instances (p. ). accordingly, rather than adjusting our notion of art to the western avant- garde, we should start from a shared intuitive understanding of the concept. in chapter of the book under review, dutton offers a list of twelve criteria on the basis of which we spontaneously recognize works of art. some of them – such as the fact that artworks in some sense represent the world, or that they are placed within traditions and institutions – might be approved of by danto or dickie. others, such as skill or virtuosity, would be rejected by these leading estetika: the central european journal of aesthetics, xlviii/iv, , no. , – reviews zlom _ . . : stránka aestheticians – precisely because the avant-garde works these authors favour do not require any apparent skill. dutton’s criteria of art are ‘its traditional, customary, or pretheoretical characteristics’ (p. ). hence they include features that come to anybody’s mind when confronted with an artifact – does it show skill? is it pleasurable to look at or listen to? does it express emotion? – and not features known to experts, such as form. we are likely to recognize the items from dutton’s list as familiar. he then goes on to solve some puzzles. for example, are sports events artistic performances by dutton’s criteria? he thinks not, since the crucial point for sports fans is who actually wins the game, whereas a work of art – or its performance – is a vehicle of imaginative experience, which is ‘perhaps the most important of all characteristics’ on dutton’s list (p. ). on the other hand, duchamp’s readymades, while not providing much by way of imaginative experience either, satisfy most of the other criteria – including, surprisingly enough, skill. however, it is a special kind of skill: ‘knowing exactly what unusual, however minimal, act will be admired by a sophisticated art-world audience’ (p. ). a natural accompaniment to a view like danto’s, which gears the concept of art to the recent western avant-garde, is the notion that other cultures lack our concept of art. first off, such a notion hardly does justice to the western aesthetic experience itself: is it possible to take seriously that the aesthetic interests of europeans were ever limited to a special, tiny class of glorified objects (painting and sculpture, once seen only in palaces, today mostly surviving in museums of fine arts), which were given rapt, disinterested attention only by a privileged elite? most of us conceive of art and aesthetic experience as a broad category that encompasses the mass arts (popular forms such as attic tragedy, victorian novels, or tonight’s television offerings), historical expressions of religious or political belief, the history of music and dance, and the immense variety of design traditions for furniture, practical implements, and architecture. far from being a small, rarefied class of objects, in the european imagination back to the greeks, art includes a staggeringly vast range of activities and creative products (p. ). secondly, we have evidence that in all times and places people looked at certain things with amazement and pleasure, admiration for their style and skill, and so on. dutton then considers danto’s thought-experiment in which two imaginary tribes both manufacture pots and baskets, but one of the tribes treats pots as artworks and baskets as utilitarian objects, while this practice is reversed in the other tribe. and this despite the fact that pots produced in both tribes are perceptually indistinguishable from each other, and likewise for baskets. danto uses this thought-experiment in support of his theory that an estetika: the central european journal of aesthetics, xlviii/iv, , no. , – reviews zlom _ . . : stránka ordinary object is turned into an artwork by an interpretation. dutton charges that this might work in the case of duchamp’s fountain, which is after all an ordinary urinal turned into an artwork by the interpretive act of an artist. however, if extended to whole art traditions, this idea is preposterous. that ‘a whole art tradition might in the real world be indiscernible from a utilitarian artifact tradition seems to me as about as likely as a monkey typing hamlet’ (p. ). such a proposal could come only from someone with no direct experience with the non-western, tribal art. (dutton also tells us that, unlike danto, he did acquire such ethnographic experience in new guinea.) if art is not a metaphysically mysterious practice confined to our culture, but rather a pleasurable yet costly activity shared across ages and cultures, then aesthetics could receive a fresh start from taking these facts more seriously. evolutionary biology teaches that traits that are universal, pleasurable, and costly are often adaptations. the question of whether art is a genuine adaptation has been debated by biologists for some time now. stephen jay gould famously argued that the arts, together with other intellectual talents that humans have, are merely ‘spandrels’ – non-functional by-products – of the single genuine adaptation that there is – namely, our large brain. unlike gould, pinker does not dismiss all our intellectual traits as so many spandrels, but it is true that he thinks of the arts as just by-products – a sort of ‘cheesecake for the mind’: harmless and pleasurable, but not serious. dutton reviews these positions in chapter and, rather than developing a theory of his own, questions the applicability to the arts of any easy contrast between adaptations and by-products. he suggests a metaphor of his own: ‘the internal combustion engine’ (p. ). the engine produces excess heat, which is a pure by-product. but this excess heat can be utilized by a heater that heats the driver/passenger compartment. here, then, something which is a by-product (excess engine heat) is used in something else which is purposefully designed for the benefit of the passengers. art can be thought along these lines, as serving genuine human interests. neither writing, nor reading, nor cheesecake, nor cadillac is a pleistocene adaptation. but no adequate grasp of their genesis and popularity can be achieved by ignoring the evolved interests and capacities that they serve or extend. human beings derive pleasure from travel, the ‘freedom of the open road’; they are a social species that likes to communicate, and a relatively omnivorous species that enjoys sweet and fat: such factors explain technologies and cultural forms both prehistoric and modern (p. ). estetika: the central european journal of aesthetics, xlviii/iv, , no. , – reviews for the art-as-cheesecake metaphor, see steven pinker, how the mind works (new york: w. w. norton, ), . zlom _ . . : stránka dutton then applies this idea of art as adaptive to the particular case of literature. fictional stories – whether oral story traditions in the ancestral environment, or modern novels, plays or movies – seem to provide three kinds of adaptive advantage (p. ). first, stories provide us with low-cost, low-risk surrogate experience. we don’t need to battle an enemy ourselves in order to experience the emotion of fear. second, stories are sources of factual information. and third, they teach us to empathize with the perspective of a fellow human being, which promotes our sociality. dutton suggests another adaptive hypothesis at the very beginning of the art instinct, in chapter . the pictures of landscapes in calendars sold around the world look very much the same: low grasses interspersed with groups of trees, flowers and fruiting plants, animals and birds, and gently rolling hills. what explains this uniformity? this gives dutton yet another opportunity to contrast his darwinian approach with danto’s culturalism. for danto, the near-universal preference for a certain type of landscape is a product of western cultural imperialism, among whose emissaries we must also count calendar-makers. in dutton’s darwinian explanation, people around the world like the kind of landscape that most resembles the savannas of east africa that our ancestors inhabited in pleistocene. given the amount of time our species spent in that environment, no wonder we like it best. in addition to the theory of natural selection which explains the origin of adaptations, darwin also came up with an alternative theory of sexual selection, in order to explain costly features such as the peacock’s tail. in his book the mating mind ( ), the evolutionary psychologist geoffrey miller appealed to this mechanism, rather than natural selection, to explain the arts. artworks are costly displays designed to impress – primarily females. dutton enthusiastically adopts this alternative hypothesis in chapter . he believes it can make sense of certain obvious features of artworks, such as their often being made of expensive materials; their production is time-consuming; even if quickly executed, the skills this requires are difficult to acquire; artworks are often all the more impressive if they are useless; some artworks are even more appreciated if they do not last very long; in addition to time, artworks require special intelligence or creativity to make (p. ). also by an appeal to the hypothesis of sexual selection, dutton can expose the strict distinction between costliness and beauty that has haunted modern aesthetic consciousness ever since kant as so much mythology. in the remainder of his book, dutton applies the elements of both darwinian mechanisms to such traditional puzzles of the philosophy of art as, for example, our aversion to forgery, the place of authorial intentions in art, the distinction between art and craft, and the relation between art, religion, morality, and estetika: the central european journal of aesthetics, xlviii/iv, , no. , – reviews zlom _ . . : stránka politics. very briefly, if art is a means of seeing ‘into another human personality’ (p. ), it is not surprising that we feel cheated upon discovering that we were looking into the mind of van meegeren rather than vermeer. given that a key function of language in social life is testing the cleverness or banality of our fellow humans, the intentional fallacy is no fallacy; we cannot help inquiring into the intentions of the artists. although both are exercises in skill, art and craft differ in that there is no foreknowledge of the end state in the arts. and art can be naughty or downright immoral, because its point is not that its fictional characters be good, but that they be interesting. as i said at the beginning, the art instinct is a terrific work, opening new vistas in the philosophy of art. rarely do we see a work so original, although its originality results from synthesizing a lot of disparate sources, rather than from a single new idea. in conclusion, we should notice that this synthesizing approach has its own drawbacks. i mentioned that dutton applies both of darwin’s theories – natural and sexual selection – to the arts. yet he seems to gloss over an apparent incompatibility between these two types of explanation when applied to a single feature. if art is an adaptation, how can it be at the same time a costly display, which is strictly speaking non-adaptive? if art is something like the peacock’s tail, should we think that it started off as something adaptive in the distant past, but metamorphosed into a mere signifier of sexual prowess later? this reading would be inconsistent, though, with what dutton says about the adaptive value of literary arts, for example. yet he does not suggest that some arts (literature?) are adaptations, while others (painting?) are mere costly ornaments. i expect that dutton’s followers in the field of darwinian aesthetics will work on these issues, as well they should. dutton has opened up a fertile perspective on the arts that is fully worthy of further development. tomáš hříbek institute of philosophy, academy of sciences jilská , prague , czech republic hribek@flu.cas.cz estetika: the central european journal of aesthetics, xlviii/iv, , no. , – reviews zlom _ . . : stránka human–computer interaction: vol , no log in | register cart home all journals human–computer interaction list of issues volume , issue human–computer interaction publish open access in this journal human-computer interaction publishes research on 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abuse forums roxanne leitão pages: - published online: dec abstract | full text | references | pdf ( kb) | permissions views crossref citations altmetric article collaboration on large interactive displays: a systematic review magdalena mateescu, christoph pimmer, carmen zahn, daniel klinkhammer & harald reiterer pages: - published online: dec abstract | full text | references | pdf ( kb) | supplemental | permissions views crossref citations altmetric explore most read articles most cited articles open access articles multimedia information for authors editors librarians societies open access overview open journals open select cogent oa dove medical press f research help and info help & contact newsroom commercial services advertising information all journals books keep up to date register to receive personalised research and resources by email sign me up taylor and francis group facebook page taylor and francis group twitter page taylor and francis group linkedin page taylor and francis group youtube page taylor and francis group weibo page copyright © informa uk limited privacy policy cookies terms & conditions accessibility registered in england & wales no. howick place | london | sw p wg accept we use cookies to improve your website experience. to learn about our use of cookies and how you can manage your cookie settings, please see our cookie policy. by closing this message, you are consenting to our use of cookies. humanitiesmar --la her legs were like twigs, but when she smiled, she was helen of troy. during that first visit, i asked about her health, which caused her to giggle. “i’m fine,” she replied. she had the voice and manner of a child. her eyes were curious like a toddler in the attic. she looked at me as though i had just given her a box of candy. she was not concerned about her blood pressure, which was high. i asked if she had taken her medicine. she had been out for several months. her previ- ous doctor had not filled her medicine because she had missed several appoint- ments. why had she missed them? “because willy needs me.” “willy?” i inquired. with that, she effervesced. her smile grew large like the sun. her eyes radiated joy. she lifted her hands like a girl impatient to tell a story. stigma, in ways that allow new possi- bilities to emerge — for self, others and our communities. pamela brett-maclean phd co-director arts and humanities in health and medicine program faculty of medicine and dentistry the university of alberta edmonton, alta. references . macgregor hn. mapping the body: tracing the personal and the political dimensions of hiv/aids in khayelitsha, south africa. anthropol med ; : - . . solomon j. living with x: a body mapping journal in the time of hiv and aids: a facilitator’s guide. . available: www.repssi.org/index.php?option =com_docman&task=cat_view&gid= &itemid= (accessed feb. ). . stewart m, brown jb, weston ww, et al. patient- centered medicine: transforming the clinical method. nd ed. abingdon, uk: radcliffe medical press; . . kleinman a. the illness narratives: suffering, healing and the human condition. new york: ba- sic books; . humanities cmaj • march , • ( ) © canadian medical association or its licensors living with hiv, imposed over their bod- ies. an overlapping outline of another person acknowledged the help they had received; other sources of strength were recognized in word and image. each artist developed a symbol of his personal power. jim located the as- trological sign aries (represented by a ram) on his brain. david depicted an image of his power symbol, a horse, on his mouth. the third artist (who pre- ferred to remain anonymous) located a dagger on his forearm. the participants described experienc- ing a heightened awareness and apprecia- tion of the various threads and storylines making up their lives. they noticed the sometimes limiting ways in which they had narrated their stories, and they had a renewed appreciation of all that helped them to sustain their courage, integrity and hope. in addition, they experienced a renewed commitment to promoting in- creased acceptance and understanding that would help reduce the stigma of hiv, a fundamental goal of the exhibit. ted kerr, canada’s first artist-in-res- idence at a community organization that provides support, education and advo- cacy in relation to hiv/aids, said “people with hiv can be in charge of their own representation. aids quilts were created to commemorate those lost to aids by others left behind. the unique stories depicted in these body maps are not dealing with the prospect e ach weekday morning, i re- view my clinic schedule to see who will be visiting. with just a glance, i can predict the tenor of the day. certain names evoke joy, others indifference, some dread. i still re- member the first day of spring, some years ago, when my schedule augured a banner day: opal hendricks was on the list. i had met mrs. hendricks years prior to that visit. her previous doctor had retired and i was assuming her care. she was then and not a day younger. her wizened face was framed by long sheaves of metallic grey hair. her hazel eyes were large and round like saucers. she had thin lips and crooked teeth, and she wore a faded brown dress, which was immaculate. she sat perfectly upright with her arms neatly folded. her hands were arthritic, of death, but represent what it is like to live with hiv and aids.” body mapping supports a process of personal reflection and making meaning that relates to one’s lived ex- perience of illness. it can also be used to augment medical histories by con- tributing to the understanding the pa- tient as a whole person, which may, in turn, yield supplementary information that is relevant to treatment and pa- tient education. heightened aware- ness of illness as lived through the body offers a way to connect with pa- tients about their experience of ill- ness, which may also be of significant therapeutic value. other possible body mapping applications come to mind, such as body mapping with pa- tients with eating disorders or those living with chronic pain. as a cartography that recognizes the lived experience of illness, body maps reveal how the biomedical intertwines with an intimately personal history. the body maps in this exhibit remind us to take the body seriously. they also al- low us to appreciate the experience of hiv/aids and related experience of a beautiful heart creative works jim’s map documents his life experiences. t e d k e rr d o i: . / cm aj . see the body maps in progress online. humanities cmaj • march , • ( ) © canadian medical association or its licensors over the next hour, i learned about willy. he was “slow.” when he was born, the doctors predicted a short life. that was years ago. now he was well — and happy. he loved to sit by his mother on the porch and watch the cars go by. and he could sit all day- long, unassisted. as i listened, i could tell that his mother assisted him with everything: walking, bathing, clothing, eating. but this had to be inferred, for she spoke only of what he could do. she savoured his every achievement and marvelled at his independence. once, he had almost buttoned his pants. on several occasions, he had correctly used a spoon. and he always recog- nized his aunt myrna. as mrs. hendricks spoke, i was drawn into her ethe- real world. she was be- witching. with her soft, feathery voice, she pranced from word to word like a fairy. her bubbly manner and impish tone had an anachronistic charm. she had aged; yet, with her son, she occupied an ever- green world where innocence prevailed. if sadness ever vis- ited, it left no footprint. to hear her was to enter a realm of verdant pastures and placid lakes. perhaps her elfish tone was an accom- modation to her son’s simplicity; or per- haps, by some miracle, her heart had been rendered impervious to erosion. i luxuriated in the cadence of her voice and was sad when her story finally ended. before she left, i filled her medi- cine and asked her to return in weeks. and return she did, repeatedly over years. at each visit, we revelled in willy’s exploits. he was achilles in an ongoing epic, the provenance of a legend. her tale was lush and limitless; her enthusiasm, incandescent. she had the world’s greatest job — willy’s mother, exalted and triumphant. over the years, mrs. hendricks missed only appointments, both be- cause she could not find a sitter for willy. but that did not matter. to fault her story complete, mrs. hen- d r i c k s f e l l s i l e n t . h e r h e a d w a s bowed, her eyes were closed, her arms outstretched. she was the pieta incarnate. i gazed at her as i would gaze upon the pyramids of giza — with awe befitting a work of ineffa- ble grandeur. that she had been devoted to her son was unre- markable, but that she had subsumed every thought, word, and action for more that years to the care of a disabled child, boy, and man — indeed, to her very soul — was breathtaking. i tried to comfort her and told her we would dis- cuss her health another time. but i knew there would be no other time. she would never return. three years passed without a word. then one day, her nephew called to say that she had died. i forwent dinner that evening and retired to my bedroom early. seeking comfort, i listened to a recording of beethoven’s fi- nal sonata and journeyed into sublimity. as the piano evanesced, i was transported to the very altar of music. mrs. hendricks’ influence had been similarly transcen- dent. she had been my bard for years. my fascination with her, borne of amusement, had evolved into a reflection on archetypal virtue. indeed, to gaze at her divine counte- nance was to rise above her broken heart, bask in her goodness, and wit- ness the face of love itself. steve blevins md assistant professor of medicine section of general internal medicine department of medicine university of oklahoma oklahoma city, oklahoma this paragon of motherhood for her tru- ancy was unfathomable. and so on that lovely spring morning years ago, i was delighted to see her name on the list. as always, she arrived punctually. i entered the room and turned to greet her. and upon seeing her, i fell speechless. she was gazing for- ward, tears streaming down her cheeks. her tortured face made me recoil. “what happened?” i asked fearfully. she responded with the plangent cry of a lamb being devoured. her eyes pro- truded as if a ghost had appeared. her lips quivered; her hands shook. through sobs and snorts, she muttered a few bro- ken words. then, slowly, as her voice cleared, she began her lachrymose tale. willy had caught a cold. after a few days, he had started to feel better, but then developed a fever. soon he was coughing and congested. the next morning, he was confused. the ambu- lance was called, but he fell asleep be- fore it arrived and never awoke. dr. blevins enjoys string quartets, french literature, european history, caribbean beaches and ice cream. the patient’s name and pertinent details have been significantly altered to conceal her identity. she passed away many years ago. sc ot t pl um be << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /all /binding /left /calgrayprofile (dot gain %) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /warning /compatibilitylevel . /compressobjects /tags /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /default /detectblends true /detectcurves . /colorconversionstrategy /leavecolorunchanged /dothumbnails false /embedallfonts true /embedopentype false /parseiccprofilesincomments true /embedjoboptions true /dscreportinglevel /emitdscwarnings false /endpage - /imagememory /lockdistillerparams false /maxsubsetpct /optimize true /opm 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. ] >> setpagedevice gender differences in the motivational processing of facial beauty | request pdf articlegender differences in the motivational processing of facial beauty may learning and motivation ( ): - doi: . /j.lmot. . . source oai authors: boaz levy boaz levy this person is not on researchgate, or hasn't claimed this research yet. dan ariely dan ariely this person is not on researchgate, or hasn't claimed this research yet. nina mazar nina mazar this person is not on researchgate, or hasn't claimed this research yet. won chi won chi this person is not on researchgate, or hasn't claimed this research yet. show all authorshide request full-text pdfto read the full-text of this research, you can request a copy directly from the authors. request full-text download citation copy link link copied request full-text download citation copy link link copied to read the full-text of this research, you can request a copy directly from the authors. citations ( ) references ( ) abstract gender may be involved in the motivational processing of facial beauty. this study applied a behavioral probe, known to activate brain motivational regions, to healthy heterosexual subjects. matched samples of men and women were administered two tasks: (a) key pressing to change the viewing time of average or beautiful female or male facial images, and (b) rating the attractiveness of these images. men expended more effort (via the key-press task) to extend the viewing time of the beautiful female faces. women displayed similarly increased effort for beautiful male and female images, but the magnitude of this effort was substantially lower than that of men for beautiful females. heterosexual facial attractiveness ratings were comparable in both groups. these findings demonstrate heterosexual specificity of facial motivational targets for men, but not for women. moreover, heightened drive for the pursuit of heterosexual beauty in the face of regular valuational assessments, displayed by men, suggests a gender-specific incentive sensitization phenomenon. discover the world's research + million members + million publications k+ research projects join for free no full-text available to read the full-text of this research, you can request a copy directly from the authors. request full-text pdf citations ( ) references ( ) ... however, none of the above studies found differences in behavioral attractiveness ratings between male and female faces or between men and women. in an attempt to further pursue the suggestion by aharon et al. ( ) that a preferred-sex bias occurs at a level of wanting rather than liking, several research groups (hayden et al., ;levy et al., ) conducted behavioral studies including both, attractiveness ratings and work-per-view-tasks. while men and women showed little difference in attractiveness ratings of opposite-sex faces, men worked significantly harder (hayden et al., ;levy et al., ), and were significantly more willing to exchange money (hayden et al., ) to extend the viewing time of an opposite-sex face than women. ... ... in an attempt to further pursue the suggestion by aharon et al. ( ) that a preferred-sex bias occurs at a level of wanting rather than liking, several research groups (hayden et al., ;levy et al., ) conducted behavioral studies including both, attractiveness ratings and work-per-view-tasks. while men and women showed little difference in attractiveness ratings of opposite-sex faces, men worked significantly harder (hayden et al., ;levy et al., ), and were significantly more willing to exchange money (hayden et al., ) to extend the viewing time of an opposite-sex face than women. ... ... however, all of the above studies included facial beauty as modulating factor, hereby blurring the boundary between sexual preference and aesthetic valuation. also, previous studies neglected the potential influence of relationship status and steroid hormone levels (except levy et al., ) on mating-related reward processing. studies on face processing have shown that being in a relationship alters women's preferences for masculinity in a man's face (little et al., ). ... neural activation during anticipation of opposite-sex and same-sex faces in heterosexual men and women article nov neuroimage katja n spreckelmeyer lena rademacher frieder michel paulus gerhard gründer psychobiological accounts of face processing predict that greater salience is attributed to faces matching a viewer's sexual preference than to faces that do not. however, behaviorally, this effect could only be demonstrated in tasks assessing reward 'wanting' (e.g. work-per-view-tasks) but not in tasks assessing 'liking' (e.g. facial attractiveness ratings), and has been found to be more pronounced in heterosexual men than women, especially with regard to very attractive faces. here, we addressed the question if sex-differences at the level of 'wanting' persist if participants are uninformed about the attractiveness of an anticipated male or female face. seventeen heterosexual men and heterosexual women (all single) participated in a social incentive delay task (sid). participants were required to react on simple graphical cues in order to view a smiling face. cues provided a priori information on the level of smile intensity (low/ medium/ high) as well as sex of the face (male/ female). a significant interaction of sex-of-face and sex-of-participant was observed in a priori defined regions of interest in the brain reward system (including ventral tegmental area, nucleus accumbens and ventromedial prefrontal cortex), reflecting enhanced activation to cues signaling opposite-sex faces relative to same-sex faces in both, men and women. women additionally recruited the temporo-parietal junction (tpj) during processing of opposite- vs. same-sex cues, suggesting stronger incorporation of social cognition processes in women than men. the findings speak against a general male bias for opposite-sex faces. instead they provide preliminary evidence that men and women recruit different brain circuits during reward value assessment of facial stimuli. view show abstract ... however, there is little research on willingness to expend effort to engage with infant stimuli ( " wanting " ). prior research on the incentive value of sex-linked stimuli has focused on effort expended to view attractive adult faces (e.g., levy et al., ), but a similar sex difference in incentive value may account for the observed sex difference in interest in infants (maestripieri, ; best & williams, ). one recent study examined this possibility but found no sex difference in the effort expended to view infant faces (parsons, young, kumari, stein, & kringelbach, ). ... ... pictures of infant faces, kittens, and dolls were included in a set of images displayed in the center of the computer screen. similar to the methods of the earlier investigation (levy et al., ), an on-screen timer indicated the amount of viewing time remaining for each picture. the set of images included three images of infants' faces, two images of kittens' faces, and two images of dolls. ... ... key presses in this study are considered indicative of " wanting " in that they demonstrate motivated behavior to either shorten or extend viewing of images of a certain type. similar to the method used in levy et al. ( ), net key press results for each category of stimuli were analyzed using a mixed design glm with sex as the between-subjects factor and stimulus type (infant, doll, kitten) as the within-subjects factor. because there were individual differences in the total number of key presses during the experiment, number of total presses was included as a covariate. ... motivational value and salience of images of infants article aug evol hum behav nora e. charles gerianne alexander janet saenz researchers have typically reported relatively greater preferences for infants among females than among males, though this varies somewhat across samples and age groups. the mechanism by which this sex difference occurs is not well understood and many studies rely on participants' self-reported preferences rather than measuring motivated behavior or patterns of visual attention directly. the present research consists of two independent studies investigating attention to infants. the aim of these studies was to extend research on the characteristics associated with interest in infants by measuring motivation to view infant faces (study ) and visual attention to infants in a complex visual scene (study ). in study , participants controlled the length of viewing time for different images. women demonstrated motivation to extend viewing of infants. men showed the opposite pattern, working to decrease the length of time they viewed infants. in study , participants were shown complex scenes that contained infants. patterns of visual attention were measured using eye-tracking technology. infants did not receive a particularly high proportion of fixations from either sex. however, there were relationships between gender-linked traits, such as digit ratio and self-reported interest in infants, and the percentage of fixations on infants. additionally, participants who reported being in a romantic relationship demonstrated greater interest in infants. this suggests the long-reported sex difference in interest in infants may relate more to current life circumstances and gender linked traits than an overwhelming tendency among all members of a sex. view show abstract ... for example, brain regions involved in the general processing of rewards, such as the nucleus accumbens and orbitofrontal cortex [ ], respond more strongly when viewing physically attractive faces than they do when viewing physically unattractive faces [ , ]. studies that have used key-press tasks to assess the motivational salience of faces (i.e., the extent to which participants will expend effort to alter the viewing time for a face) have also reported that participants will expend more effort to look longer at more attractive faces [ ][ ][ ][ ]. some studies of heterosexual participants have reported that this effect of attractiveness on the motivational salience of faces is greater when viewing opposite-sex than own-sex faces [ , ], while others have reported this opposite-sex bias for male, but not female, participants [ ], or have not observed an oppositesex bias [ ]. ... ... studies that have used key-press tasks to assess the motivational salience of faces (i.e., the extent to which participants will expend effort to alter the viewing time for a face) have also reported that participants will expend more effort to look longer at more attractive faces [ ][ ][ ][ ]. some studies of heterosexual participants have reported that this effect of attractiveness on the motivational salience of faces is greater when viewing opposite-sex than own-sex faces [ , ], while others have reported this opposite-sex bias for male, but not female, participants [ ], or have not observed an oppositesex bias [ ]. ... ... that male macaques find more dominant conspecifics' faces more rewarding [ ] suggests that the dominance component of social judgments of faces might also be associated with the motivational salience of faces in humans. this would be noteworthy because the motivational salience of faces is thought to drive the link between perceptual judgments and behavioral responses [ ][ ][ ] and such results would suggest that the motivational salience of faces is not solely a consequence of their perceived valence. ... the motivational salience of faces is related to both their valence and dominance article full-text available aug plos one hongyi wang amanda c hahn lisa m debruine benedict c jones both behavioral and neural measures of the motivational salience of faces are positively correlated with their physical attractiveness. whether physical characteristics other than attractiveness contribute to the motivational salience of faces is not known, however. research with male macaques recently showed that more dominant macaques’ faces hold greater motivational salience. here we investigated whether dominance also contributes to the motivational salience of faces in human participants. principal component analysis of third-party ratings of faces for multiple traits revealed two orthogonal components. the first component (“valence”) was highly correlated with rated trustworthiness and attractiveness. the second component (“dominance”) was highly correlated with rated dominance and aggressiveness. importantly, both components were positively and independently related to the motivational salience of faces, as assessed from responses on a standard key-press task. these results show that at least two dissociable components underpin the motivational salience of faces in humans and present new evidence for similarities in how humans and non-human primates respond to facial cues of dominance. view show abstract ... responses to images of preferred-sex and non-preferred-sex individuals in heterosexual women, evidence for this pattern of results in studies using key-press tasks is more mixed. for example, levy et al. ( ) found that heterosexual men, but not heterosexual women, exerted more effort to view images of preferred-sex faces than images of non-preferred-sex faces. by contrast, hahn, xiao, sprengelmeyer, and perrett ( ) found that both heterosexual men and women exerted more effort to view images of preferred-sex faces than of nonpreferred-sex faces. ... ... by contrast, hahn, xiao, sprengelmeyer, and perrett ( ) found that both heterosexual men and women exerted more effort to view images of preferred-sex faces than of nonpreferred-sex faces. both levy et al. ( ) and hahn et al. ( ) also presented evidence that the degree of specificity observed in key-press responses to preferred-sex and non-preferred-sex faces can be influenced by the physical attractiveness of the individuals presented. the tendency for heterosexual men in levy et al.'s study and heterosexual men and heterosexual women in hahn et al.'s study to exert more effort to view preferred-sex faces than non-preferred-sex faces was greater for images of physically attractive individuals than for images of relatively unattractive individuals. ... ... the purpose of the current study was to investigate the effects of participant sexual orientation (homosexual vs. heterosexual), participant sex (male vs. female), image sex (preferred-sex vs. non-preferred-sex), and the physical attractiveness of the individual shown in the image on the reward value of faces. reward value was assessed using a standard key-press task adapted from those used previously to explore the effects of image sex and physical attractiveness in studies of the reward value of faces in heterosexual participants (aharon et al., ; hahn et al., ; levy et al., ). given that several lines of evidence suggest that heterosexual women show weaker sex-specific responses to preferred-sex versus non-preferred-sex individuals, we might expect sex-specific responses to faces to be weaker (or even absent) in heterosexual women compared with heterosexual men, homosexual men, or homosexual women. ... sex-specificity in the reward value of facial attractiveness article apr arch sex behav lisa m debruine amanda c hahn claire i. fisher benedict c jones studies of the sex-specificity of sexual arousal in adults (i.e., the tendency to respond more strongly to preferred-sex individuals than non-preferred sex individuals) have suggested that heterosexual men, homosexual men, and homosexual women show stronger sex-specific responses than do heterosexual women. evidence for a similar pattern of results in studies investigating the reward value of faces is equivocal. consequently, we investigated the effects of ( ) sexual orientation (homosexual vs. heterosexual), ( ) sex (male vs. female), ( ) image sex (preferred-sex vs. non-preferred-sex), and ( ) the physical attractiveness of the individual shown in the image on the reward value of faces. participants were heterosexual men, homosexual men, heterosexual women, and homosexual women. the reward value of faces was assessed using a standard key-press task. multilevel modeling of responses indicated that images of preferred-sex individuals were more rewarding than images of non-preferred-sex individuals and that this preferred-sex bias was particularly pronounced when more physically attractive faces were presented. these effects were not qualified by interactions involving either the sexual orientation or the sex of our participants, however, suggesting that the preferred-sex bias in the reward value of faces is similar in heterosexual men, homosexual men, heterosexual women, and homosexual women. view show abstract ... the approach/avoidance task (kim et al., ) gauged to what extent subjects would actively keypress to increase or decrease the amount of time they were exposed to face stimuli belonging to four categories: non-model male, nonmodel female, model male, and model female faces (aharon et al., ). this validated task (aharon et al., ;elman et al., ;strauss et al., ;levy et al., ;perlis et al., ;gasic et al., ;yamamoto et al., ;kim et al., ;viswanathan et al., ) quantified the effort subjects were willing to expend to approach or avoid each face stimulus. we then computed metrics that quantified the magnitude and predictability of the participants' keypress behavior. ... ... subjects were told that they would be exposed to a series of pictures that would change every s ( figure a) if they pressed no keys. as published previously (aharon et al., ;elman et al., ;strauss et al., ;levy et al., ;makris et al., ;perlis et al., ; figure | experimental paradigms for approach/avoidance and signal detection tasks. (a) a schema for the keypress paradigm shows, at top, raster plots of keypressing effects on face viewing time (y-axis) as blue curves going up or down from a default viewing time of s. ... ... gasic et al., ;yamamoto et al., ;kim et al., ;lee et al., ;viswanathan et al., ), each experimental stimulus would be initially presented for . s and replaced by a fixation point for . s (the "decision block"), until the face reappeared at s and the subject was given the option to increase or decrease the viewing time via keypressing the "judgment block"). the relationship between the number of keypresses made by the subject to approach or avoid the face stimuli and the updated viewing time followed previous methods, and utilized the following resistive function (aharon et al., ;elman et al., ;strauss et al., ;levy et al., ;makris et al., ;perlis et al., ;gasic et al., ;yamamoto et al., ;kim et al., ;lee et al., ;viswanathan et al., ): ... a quantitative relationship between signal detection in attention and approach/avoidance behavior article full-text available feb john p. sheppard byoung woo kim vijay viswanathan hans breiter this study examines how the domains of reward and attention, which are often studied as independent processes, in fact interact at a systems level. we operationalize divided attention with a continuous performance task and variables from signal detection theory (sdt), and reward/aversion with a keypress task measuring approach/avoidance in the framework of relative preference theory (rpt). independent experiments with the same subjects showed a significant association between one sdt and two rpt variables, visualized as a three-dimensional structure. holding one of these three variables constant, further showed a significant relationship between a loss aversion-like metric from the approach/avoidance task, and the response bias observed during the divided attention task. these results indicate that a more liberal response bias under signal detection (i.e., a higher tolerance for noise, resulting in a greater proportion of false alarms) is associated with higher “loss aversion.” furthermore, our functional model suggests a mechanism for processing constraints with divided attention and reward/aversion. together, our results argue for a systematic relationship between divided attention and reward/aversion processing in humans. view show abstract ... the motivational value of facial beauty has been evidenced both by laboratory-based research (e.g., levy et al., ) and by numerous neuroimaging studies (e.g., aharon et al., ;kampe et al., ;o'doherty et al., ;kranz and ishai, ;ishai, ). more specifically, functional brain imaging studies have shown that facial beauty evokes activation in brain regions that are involved in stimulus-reward associations (e.g., in the orbitofrontal cortex or the ventral striatum) and thus form key structures that support affect and emotion. ... ... in a similar vein, levy et al.'s ( ) study, which used laboratory performance tasks, showed that facial beauty attracts attention and has high incentive value. levy et al. ( ) examined the effect of gender on the processing of facial beauty by asking male and female participants to control the viewing time of average or beautiful faces of men and women, as well as to rate their attractiveness. ... ... in a similar vein, levy et al.'s ( ) study, which used laboratory performance tasks, showed that facial beauty attracts attention and has high incentive value. levy et al. ( ) examined the effect of gender on the processing of facial beauty by asking male and female participants to control the viewing time of average or beautiful faces of men and women, as well as to rate their attractiveness. the two groups of participants gave similar ratings of heterosexual facial attractiveness. ... facial beauty affects implicit and explicit learning of men and women differently article full-text available aug eleni ziori zoltan dienes the present work explores the unconscious and/or conscious nature of learning attractive faces of same and opposite sex, that is, of stimuli that experimental and neuroimaging research has shown to be rewarding and thus highly motivating. to this end, we examined performance of men and women while classifying strings of average and attractive faces for grammaticality in the experimental task of artificial grammar learning (agl), which reflects both conscious and unconscious processes. subjective measures were used to assess participants' conscious and unconscious knowledge. it was found that female attractiveness impaired performance in male participants. in particular, male participants demonstrated the lowest accuracy while classifying beautiful faces of women. conversely, female attractiveness facilitated performance in female participants. the pattern was similar for conscious and unconscious knowledge. presumably, objects with high incentive salience, as are beautiful faces, captured resources, which were used in task relevant versus task irrelevant ways by women versus men. the present findings shed light on the relation of conscious and unconscious processing with affective and reward-related stimuli, as well as on gender differences underlying this relation. view show abstract ... in each test session, participants completed two versions of a standard key-press task, similar to those used to assess the motivational salience of faces in previous studies (aharon et al., ;levy et al., ;hahn et al., ). following aharon et al. ( ) and levy et al. ( ), and because the faces had been rated in single-sex blocks (see section . ), male and female faces were presented in separate blocks of trials. ... ... in each test session, participants completed two versions of a standard key-press task, similar to those used to assess the motivational salience of faces in previous studies (aharon et al., ;levy et al., ;hahn et al., ). following aharon et al. ( ) and levy et al. ( ), and because the faces had been rated in single-sex blocks (see section . ), male and female faces were presented in separate blocks of trials. in one version of the task (male face version), the male faces described in section . were presented in a fully randomized order. ... ... following previous studies of the motivational salience of faces (aharon et al., ;levy et al., ;hahn et al., ), key-press scores for each face were calculated by subtracting the number of key presses made to decrease viewing time from those made to increase viewing time. these scores were calculated separately for each participant and for each test session and served as the dependent variable in our analyses (see section ). ... women's hormone levels modulate the motivational salience of facial attractiveness and sexual dimorphism article sep psychoneuroendocrino hongyi wang claire i. fisher benedict c jones amanda c hahn view ... in study , we used a standard key-press task (aharon et al., ;, levy et al., ;wang, hahn, fisher, debruine, & jones, ) to assess the reward value of images of men's faces in partnered and unpartnered women. in this task, participants can control the length of time for which they view faces by repeatedly pressing keys to either increase or decrease the viewing time (aharon et al., ;hahn et al., hahn et al., , levy et al., ;wang et al., ). ... ... in study , we used a standard key-press task (aharon et al., ;, levy et al., ;wang, hahn, fisher, debruine, & jones, ) to assess the reward value of images of men's faces in partnered and unpartnered women. in this task, participants can control the length of time for which they view faces by repeatedly pressing keys to either increase or decrease the viewing time (aharon et al., ;hahn et al., hahn et al., , levy et al., ;wang et al., ). responses on this type of key-press task are a better predictor of neural measures of the reward value and motivational salience of face images than attractiveness ratings (aharon et al., ). ... ... the same face stimuli were used in both studies. previous research has found that more attractive male faces have greater reward value to women (hahn et al., , levy et al., ;wang et al., ). however, this work has not considered the possible effects of women's partnership status. ... do partnered women discriminate men's faces less along the attractiveness dimension? article full-text available aug pers indiv differ hongyi wang amanda c hahn lisa m debruine benedict c jones romantic relationships can have positive effects on health and reproductive fitness. given that attractive potential alternative mates can pose a threat to romantic relationships, some researchers have proposed that partnered individuals discriminate opposite-sex individuals less along the physical attractiveness dimension than do unpartnered individuals. this effect is proposed to devalue attractive (i.e., high quality) alternative mates and help maintain romantic relationships. here we investigated this issue by comparing the effects of men's attractiveness on partnered and unpartnered women's performance on two response measures for which attractiveness is known to be important: memory for face photographs (study ) and the reward value of faces (study ). consistent with previous research, women's memory was poorer for face photographs of more attractive men (study ) and more attractive men's faces were more rewarding (study ). however, in neither study were these effects of attractiveness modulated by women's partnership status or partnered women's reported commitment to or happiness with their romantic relationship. these results do not support the proposal that partnered women discriminate potential alternative mates along the physical attractiveness dimension less than do unpartnered women. view show abstract ... behavioral work utilizing the key-press paradigm has provided some evidence for sex differences in response to facial attractiveness. both men and women will exert greater effort to view attractive than unattractive faces (aharon et al., ;dai et al., ;hahn et al., b;iaria et al., ;levy et al., ) and there is some evidence that both sexes exert greater effort for opposite-sex faces than same-sex faces overall (hahn et al., b;iaria et al., ). same-sex faces in general, however, may hold greater incentive salience among women than men (dai et al., ;hahn et al., b;iaria et al., ;levy et al., ), although attractiveness does impact on the incentive salience of both samesex and opposite-sex faces (e.g., dai et al., ;elman et al., ). ... ... both men and women will exert greater effort to view attractive than unattractive faces (aharon et al., ;dai et al., ;hahn et al., b;iaria et al., ;levy et al., ) and there is some evidence that both sexes exert greater effort for opposite-sex faces than same-sex faces overall (hahn et al., b;iaria et al., ). same-sex faces in general, however, may hold greater incentive salience among women than men (dai et al., ;hahn et al., b;iaria et al., ;levy et al., ), although attractiveness does impact on the incentive salience of both samesex and opposite-sex faces (e.g., dai et al., ;elman et al., ). ... neural and behavioral responses to attractiveness in adult and infant faces article oct neurosci biobehav r amanda c hahn david i perrett view ... although racial it can be assumed from this data, that laypeople are either the most critical at assessing facial esthetics or that facial esthetics does not depend on any one single feature. this data indicates that subject's background status does not relate to an increased ability to detect changes in lfh in models with ovd increases up to . mm. these results therefore fail to reject the null hypothesis. ... ... and gender preferences have been validated by previous research in psychology, most previous dental literature in facial esthetics has been conducted regionally and with sizable gender and racial preferences; this affects sample homogeneity and may contribute biases in ratings.data from part b is as follows. first, ratings of facial esthetics were not influenced by the alterations of ovd used here. ... changes in facial esthetics and lower facial height with increases in occlusal vertical dimension in dentate models article jun orenstein, noah philip, dmd materials and methods: twenty models with class i occlusion of white, black, asian, and asian-indian racial background had mandibular overlays of mm, mm, mm, and mm thicknesses fabricated. each model had clinical measurements made from pro-nasale to soft tissue menton for each of the following ovd above their normal bite mm, mm, mm, mm, and mm. the same models described above had frontal and profile facial digital images recorded in maximum intercuspation (mip) and wearing each of the four mandibular overlays. the digital images of models were selected and displayed to judges ( laypeople, general dentists, and prosthodontists.) using a vas, all subjects rated the esthetics of each model at each ovd. results: objectively, a systematic increase of . mm in ovd reflected an increase of lfh by . ; this increase in lfh was uncorrelated with ovd (r=. ; p >. ). subjectively, ratings of facial esthetics, evaluated across judges with different background statuses (layperson, general dentist, prosthodontist), were not affected (p> . ) up to . mm above mip. when model and subject gender were the same (p > . ) ratings of facial esthetics were not correlated, but when model and subject race were the same (p < . ) ratings were affected. conclusion: objectively, increased ovd did not correlated to similar increases in lfh. subjectively, judges could not detect a difference in facial esthetics with changes up to . mm above mip irrespective of background status. interactions between model and subject gender affected ratings, but interactions between model and subject race were uncorrelated. view show abstract ... evolutionary social psychology has suggested that facial attractiveness indicates the reproductive capacities and genetic fitness of potential mates [ , ]. although women are also intrinsically attracted to beauty, research observed that men tend to value physical attractiveness more highly than women do [ ]. for instance, a study showed that men are willing to wait longer, exchange more money, and devote more effort than females for the opportunity to look at attractive opposite-sex faces [ ]. ... ... given that beauty is positively associated with social competence and negatively with neediness, women would perceive less neediness and empathy toward more attractive recipients and would give less to them than less attractive recipients. in contrast, compared with women, men are more sensitive, attentive, and tend to assign higher values to attractive targets, especially female targets [ , ]. as a consequence, men tend to positively react to more attractive females than less attractive females [ , ]. ... the role of beauty in donation crowdfunding conference paper jan jooyoung park keongtae kim view ... it biases our perception of direct eye contact (kloth et al., ), and induces a pleasurable perceptual experience. attractiveness alters our behavior, so that we look longer at attractive faces (aharon et al., ;levy et al., ) in social scenes (leder et al., ;mitrovic et al., ). attractive faces may be looked at longer because looking at them is rewarding and they elicit positive emotions (hayden et al., ). ... ... among other benefits, facial attractiveness has a rewarding value. for example, we are biased to perceive direct eye contact in attractive faces (kloth et al., ) and receive reward when looking at attractive faces (aharon et al., ;levy et al., ). this reward might indicate potential approach behavior in social interactions. ... combined effects of gaze and orientation of faces on person judgments in social situations article full-text available feb raphaela kaisler helmut leder in social situations, faces of others can vary simultaneously in gaze and orientation. how these variations affect different kinds of social judgments, such as attractiveness or trustworthiness, is only partly understood. therefore, we studied how different gaze directions, head angles, but also levels of facial attractiveness affect perceived attractiveness and trustworthiness. we always presented pairs of faces – either two average attractive faces or a highly attractive together with a less attractive face. we also varied gaze and head angles showing faces in three different orientations, front, three-quarter and profile view. in experiment (n = ), participants rated averted gaze in three-quarter views as more attractive than in front and profile views, and evaluated faces with direct gaze in front views as most trustworthy. moreover, faces that were being looked at by another face were seen as more attractive. independent of the head orientation or gaze direction, highly attractive faces were rated as more attractive and more trustworthy. in experiment (n = ), we found that the three-quarter advantage vanished when the second face was blurred during judgments, which demonstrates the importance of the presence of another person-as in a triadic social situation-as well as the importance of their visible gaze. the findings emphasize that social evaluations such as trustworthiness are unaffected by the esthetic advantage of three-quarter views of two average attractive faces, and that the effect of a faces’ attractiveness is more powerful than the more subtle effects of gaze and orientations. view show abstract ... the females were very keen to use sexual gestures such as dancing and blowing kisses. this is somewhat at odds with a study by levya et al. ( ) who found in a study of responses to facial beauty that 'men expended substantially greater motivational effort for viewing beautiful female images than women for beautiful males'. the attractive female received the most attention from the males. ... an investigation into how avatar appearance can affect interactions in a virtual world article full-text available jan leonie o'brien john stanley murnane in the virtual world of second life, participants create their own avatar to represent them. from an initial template, this avatar can be physically manipulated in multiple ways to individualise its look and behaviour. this pilot study reports on the social experience of a male and female avatar in a controlled environment. each avatar had an 'attractive' and 'unattractive' representation. in line with similar studies in real life, we found that attractive people are more likely to be included in conversations and interactions in a virtual online environment and are more likely to be offered friendship than their more unattractive counterparts, but the more interesting questions involved deeper interactions related to deliberate 'unattractiveness' and its possible motives. view show abstract ... in short, preferences do not necessarily lead to mating, and mating may not occur with the preferred mate. further, recent studies investigating preference ratings and behavioural measures in humans have shown that people expend more effort for opposite sex faces that elicit responses in brain regions associated with reward, despite rating same sex faces as equally attractive (aharon et al. ;levy et al. ). that is, 'liking' can be dissociated from 'wanting' (rob-inson and berridge ). ... multiple signals in human mate selection: a review and framework for integrating facial and vocal signals article full-text available jun timothy wells andrew k dunn mark j.t. sergeant mark davies evolutionary adaptation in variable environments is likely to give rise to several signals that can be used to identify a suitable mate in multisensory organisms. the presence of multiple signals for sexual selection could be advantageous, limiting the chance of mating with a suboptimal partner and avoiding the costs of inferior progeny. despite extensive research into isolated signals of attractiveness, the amalgamation of multiple signals in sexual selection is poorly understood, particularly in humans. inferences regarding both the function and importance of such signals are therefore tentative unless the effects are considered together. here, the literature regarding two evolved signals of attraction (cf. faces and voices) is reviewed in relation to a framework ( candolin ) for signal integration. it is argued that the functional nature of signals of attractiveness would be better studied through manipulation and experimentation with both single and multiple signals. considering the prevalence of traits in relation to their combined effects may well provide a more fruitful and informative approach to human mate selection. view show abstract ... aharon et al. ( ) stwierdzili, że mężczyźni dają wysokie oceny atrakcyjności niektórym twarzom kobiet i niektórym twarzom mężczyzn, ale jedynie w stosunku do atrakcyjnych twarzy kobiet mężczyzna zabiega o to, by je dłużej oglądać (w tym eksperymencie: wielokrotne naciskanie klawisza na klawiaturze powodowało dłuższe wyświetlanie twarzy na ekranie). levy et al. ( ) umożliwili badanym zarówno skracanie jak i wydłużanie czasu prezentacji twarzy i uzyskali następujące wyniki: (i) obie płcie nieco skracają czas dla twarzy (obu płci) o przeciętnej atrakcyjności, a silnie -dla twarzy nieatrakcyjnych, (ii) kobiety wydłużają czas dla atrakcyjnych twarzy obu płci, (iii) mężczyźni silnie wydłużają czas dla atrakcyjnych twarzy kobiecych, ale skracają dla atrakcyjnych twarzy męskich. również w trakcie standardowych badań nad atrtw, sędziowie obu płci zdecydowanie dłużej patrzą na atrakcyjną twarz zanim dokonają jej oceny niż na twarz nieatrakcyjną (shimojo et al. , honekopp oraz na twarz kobiety niż mężczyzny (fisher ). ... atrakcyjność twarzy ( ) article full-text available jan krzysztof kościński abstrakt: atrakcyjność twarzy była przedmiotem rozważań już w starożytności, ale naukowe badania nad nią pochodzą głównie z ostatniego ćwierćwiecza. badania te dowiodły, że istnieje szereg, często mierzalnych, własności twarzy, które wpływają atrakcyjności twarzy. przeciętność proporcji oraz symetria twarzy są preferowane przypuszczalnie dlatego, że sygnalizują zdrowie genetyczne i wysoką tzw. stabilność rozwojową. mężczyźni preferują silnie sfeminizowane twarze kobiet, ponieważ oznaczają one wysoki stosunek poziomu estrogenu do testosteronu, a zatem sprawność reprodukcyjną kobiety. natomiast kobiety preferują umiarkowany stopień maskulinizacji twarzy mężczyzn, ponieważ znaczna maskulinizacja sygnalizuje wysoki poziom testosteronu, a zatem słabo wykształcone pro-rodzinne cechy osobowości. z podobnych przyczyn mężczyźni preferują brak owłosienia twarzy kobiet, a kobiece preferencje dla zarostu twarzy mężczyzn są niejednolite. czysta (tzn. pozbawiona brodawek itp.) skóra twarzy jest atrakcyjna u obu płci. ponadto mężczyźni preferują u kobiet skórę jasną i gładką (tzn. bez zmarszczek). korzystny wpływ na atrakcyjność twarzy ma też pozytywny wyraz twarzy. wiele z wyżej wymienionych cech (przede wszystkim stan skóry i proporcje twarzy) wpływa na postrzegany wiek, a ten z kolei wpływa na atrakcyjność twarzy. szczególnie mężczyźni silnie preferują młodo wyglądające twarze kobiet. badania pokazują, że preferencje względem twarzy w dużej mierze są kryteriami rozpoznawania wartościowych, z reprodukcyjnego punktu widzenia, partnerów. preferencje te mają zatem charakter adaptacji, choć w niektórych przypadkach istotną rolę mogą także odgrywać nie-adaptacyjne mechanizmy związane z ogólnymi sposobami funkcjonowania mózgu. w niniejszej pracy dużo miejsca poświęcono wewnątrz-i międzypopulacyjnej zmienności preferencji, związkowi pomiędzy atrakcyjnością twarzy a wartością partnerską, biologicznym i społecznym konsekwencjom atrakcyjności oraz wiarygodności adaptacyjnego rozumienia preferencji względem twarzy. wyniki badań skłaniają do następujących wniosków: ( ) istnieje wiele czynników przyczyniających się do międzyosobniczej zmienności postrzegania atrakcyjności twarzy, np. wiek, płeć, jakość biologiczna, stan fizjologiczny, osobowość i sytuacja życiowa osoby oceniającej twarze, a także poprzednio oglądane twarze, podobieństwo pomiędzy ocenianą twarzą a twarzą sędziego, oraz znajomość właściciela twarzy i wiedza o nim. ( ) międzypopulacyjne podobieństwo w postrzeganiu atrakcyjności twarzy jest znaczne i ma podłoże zarówno biologiczne jak i kulturowe. ( ) osoby o atrakcyjnych twarzach mają więcej partnerów seksualnych, biorą ślub młodszym wieku i rzadziej pozostają starymi pannami / kawalerami. z tych powodów mają oni większy sukces reprodukcyjny niż osoby nieatrakcyjne. ( ) atrakcyjność twarzy jest rzetelnym wskaźnikiem jakości biologicznej jej właściciela, np. odporności na pasożyty, sprawności fizycznej, sprawności reprodukcyjnej, długowieczności, inteligencji, zdrowia psychicznego, a także mniejszej liczby mutacji. ( ) całościowo, badania empiryczne potwierdzają tezę, że preferencje w odniesieniu do twarzy są biologicznymi adaptacjami, to znaczy, wykształciły się one na drodze ewolucji biologicznej, ponieważ pomagały w wyborze partnera o dobrych genach lub pożądanej osobowości. słowa kluczowe: atrakcyjność twarzy, atrakcyjność fizyczna, preferencje estetyczne, twarz człowieka, piękno. view show abstract ... additional perspectives entail studies in healthy participants and patients with hsdd investigating sex differences in the beautyattractiveness dissociation. indeed, as men give more credit to physical appearance when choosing mates, the motivational value of a beautiful female face may be higher [ ] and beauty-attractiveness dissociation could thus be less marked in men than in women. it could have implications for the management of hsdd as cognitive characteristics of person perception in men and women with hypoactive sexual desire might thus differ. ... perception of men's beauty and attractiveness by women with low sexual desire article dec j sex med camille ferdenzi sylvain delplanque olga vorontsova-wenger david sander introductiondespite the high prevalence of hypoactive sexual desire disorder (hsdd), especially among women, this sexual disorder remains poorly understood. among the multiple factors possibly involved in hsdd, particularities in the cognitive evaluations of social stimuli need to be better characterized. especially, beauty and attractiveness judgments, two dimensions of interpersonal perception that are related but differ on their underlying motivational aspects, may vary according to the level of sexual desire.aimthe main goal of this study was to investigate whether women with and without hsdd differ in their evaluations of beauty and attractiveness of men's faces and voices.methods young women from the general population (controls, n = ) and with hsdd (patients, n = ) took part in the study. they were presented with a series of neutral/nonerotic voices and faces of young men from the geneva faces and voices database.main outcome measuresratings of beauty (i.e., assessments of aesthetic pleasure) and of attractiveness (i.e., assessments of the personal propensity to feel attracted to someone) and the frequency to which the participants pressed a key to see or listen to each stimulus again were the main outcome measures.resultsratings of attractiveness were lower than ratings of beauty in both groups of women. the dissociation between beauty and attractiveness was larger in women with hsdd than in control participants. patients gave lower attractiveness ratings than the controls and replayed the stimuli significantly less often.conclusion these results suggest that women with hsdd are characterized by specific alterations of the motivational component of men's perception, very early in the process of interpersonal relationships. our findings have significant implications, both in better understanding the specific cognitive processes underlying hypoactive sexual desire and more largely the evaluative processes involved in human mate choice. ferdenzi c, delplanque s, vorontsova-wenger o, pool e, bianchi-demicheli f, and sander d. perception of men's beauty and attractiveness by women with low sexual desire. j sex med ; : - . view show abstract ... it has been demonstrated that women spend more time looking at the eyes whereas men pay more attention to central parts of faces (nose, mouth), indicating a more globally oriented processing [ ] based on a centred viewpoint compared to more fixations at the eyes in a local strategy [ ]. moreover, men exhibit greater interest in opposite-sex faces than women [ ] and value attractiveness higher than women [ , ] which is reflected in stronger recruitment of reward-related areas in men viewing attractive female faces [ ]. the processing and appreciation of certain social aspects of faces and essentially attractiveness arguably requires more holistic processing [ , ]. ... sex-differences of face coding: evidence from larger right hemispheric m in men and dipole source modelling article full-text available jul plos one hannes o tiedt joachim e weber alfred pauls andreas lueschow the processing of faces relies on a specialized neural system comprising bilateral cortical structures with a dominance of the right hemisphere. however, due to inconsistencies of earlier findings as well as more recent results such functional lateralization has become a topic of discussion. in particular, studies employing behavioural tasks and electrophysiological methods indicate a dominance of the right hemisphere during face perception only in men whereas women exhibit symmetric and bilateral face processing. the aim of this study was to further investigate such sex differences in hemispheric processing of personally familiar and opposite-sex faces using whole-head magnetoencephalography (meg). we found a right-lateralized m -component in occipito-temporal sensor clusters in men as opposed to a bilateral response in women. furthermore, the same pattern was obtained in performing dipole localization and determining dipole strength in the m -timewindow. these results suggest asymmetric involvement of face-responsive neural structures in men and allow to ascribe this asymmetry to the fusiform gyrus. this specifies findings from previous investigations employing event-related potentials (erp) and loreta reconstruction methods yielding rather extended bilateral activations showing left asymmetry in women and right lateralization in men. we discuss our finding of an asymmetric fusiform activation pattern in men in terms of holistic face processing during face evaluation and sex differences with regard to visual strategies in general and interest for opposite faces in special. taken together the pattern of hemispheric specialization observed here yields new insights into sex differences in face perception and entails further questions about interactions between biological sex, psychological gender and influences that might be stimulus-driven or task dependent. view show abstract ... social attachment is certainly purported to be the "primary form of addiction" (burkett and young, ;insel, ;zellner et al., ). several lines of evidence support this sort of conceptualization, including heightened incentive salience assigned to heterosexual beauty, the term typically refers to a situation where the motivational targets that are 'wanted' more than could be explained by their hedonic properties, that is to say, 'liking', which may be akin to the urges to seek drugs despite their diminished (or absent) hedonic qualities (levy, ). in addition, euphoria of early encounters with the love object is indistinguishable from drug-induced high. ... pain and suicidality: insights from reward and addiction neuroscience. article jul prog neurobiol igor elman david borsook nora d volkow suicidality is exceedingly prevalent in pain patients. although the pathophysiology of this link remains unclear, it may be potentially related to the partial congruence of physical and emotional pain systems. the latter system's role in suicide is also conspicuous during setbacks and losses sustained in the context of social attachments. here we propose a model based on the neural pathways mediating reward and anti-reward (i.e., allostetic adjustment to recurrent activation of the reward circuitry); both are relevant etiologic factors in pain, suicide and social attachments. a comprehensive literature search on neurobiology of pain and suicidality was performed. the collected articles were critically reviewed and relevant data were extracted and summarized within four key areas: ( ) physical and emotional pain, ( ) emotional pain and social attachments, ( ) pain- and suicide-related alterations of the reward and anti-reward circuits as compared to addiction, which is the premier probe for dysfunction of these circuits and ( ) mechanistically informed treatments of co-occurring pain and suicidality. pain-, stress- and analgesic drugs-induced opponent and proponent states of the mesolimbic dopaminergic pathways may render reward and anti-reward systems vulnerable to sensitization, cross-sensitization and aberrant learning of contents and contexts associated with suicidal acts and behaviors. these findings suggest that pain patients exhibit alterations in the brain circuits mediating reward (depressed function) and anti-reward (sensitized function) that may affect their proclivity for suicide and support pain and suicidality classification among other "reward deficiency syndromes" and a new proposal for "enhanced anti-reward syndromes". we suggest that interventions aimed at restoring the balance between the reward and anti-reward networks in patients with chronic pain may help decreasing their suicide risk. view show abstract ... second, research has demonstrated that humans spend more time looking at faces that are considered attractive than at less attractive faces (e.g., aharon et al., ;shimojo et al., ;sui and liu, ;leder et al., ;chen et al., ). however, these effects are not the same in all individuals: compared to women, men exhibit a higher motivation to view attractive opposite-sex faces (levy et al., ;hahn et al., ) and are more likely to show attentional biases toward attractive opposite-sex stimuli (maner et al., (maner et al., , . ... using eye tracking to test for individual differences in attention to attractive faces article full-text available feb christian valuch lena s. pflüger bernard wallner ulrich ansorge we assessed individual differences in visual attention toward faces in relation to their attractiveness via saccadic reaction times. motivated by the aim to understand individual differences in attention to faces, we tested three hypotheses: (a) attractive faces hold or capture attention more effectively than less attractive faces; (b) men show a stronger bias toward attractive opposite-sex faces than women; and (c) blue-eyed men show a stronger bias toward blue-eyed than brown-eyed feminine faces. the latter test was included because prior research suggested a high effect size. our data supported hypotheses (a) and (b) but not (c). by conducting separate tests for disengagement of attention and attention capture, we found that individual differences exist at distinct stages of attentional processing but these differences are of varying robustness and importance. in our conclusion, we also advocate the use of linear mixed effects models as the most appropriate statistical approach for studying inter-individual differences in visual attention with naturalistic stimuli. view show abstract ... locke introduced motivation as one of the steps for achieving communication effectiveness [ ]. scott insisted that without a sufficient level of motivation, communication may not be successful [ ]. anthony and govindarajan though, showed that a company must increase motivation through development the communication to improve decisions and financial success [ ]. ... strategic operations management: investigating the factors impacting communication effectiveness and job satisfaction article full-text available dec hassan jorfi saeid jorfi in today's strategic management, emotional intelligence in organizations of iran plays a main role among manager and employees worldwide. the paper is undertaken to understand the roles of strategic behaviour and motivation with relationship between managers’ emotional intelligence and employees to improve communication effectiveness and job satisfaction in organizations of iran. data (n= ) for this study were collected through questionnaires that participants were managers and employees of agricultural bank of iran. the aim of this paper assesses the emotional intelligence with communication effectiveness and motivation as moderator in agricultural bank of iran. strategic management plays an important role in strategic behaviours of managers and employees in organizations. also, on the other hand, strategic management has a positive relationship with strategic alignment and strategic alignment can impact motivation in this study. effective strategic alignment has a positive effect on the motivation of managers and employees in organizations of iran. additionally emotional intelligence influenced by strategic behaviour in this relationship.the result of the paper shows a strong correspondence between motivation with the relationship between emotional intelligence and communication effectiveness, and also communication effectiveness with job satisfaction. view show abstract ... although our previous studies have established a potential link between reproductive hormone status and cuteness sensitivity, we currently do not know whether reproductive hormone status modulates the aesthetic salience ('liking') or the incentive salience ('wanting') of infant faces, and whether aesthetic salience and incentive salience of infant faces are linked. both 'liking' (as assessed with a rating task) and 'wanting' (as assessed with a 'pay per view task') are dissociable components of the reward process and associated with separable neural structures; 'liking' is associated with fronto-temporal brain regions, whereas 'wanting' is associated with mesolimbic brain regions [ , , ]. ... aesthetic and incentive salience of cute infant faces: studies of observer sex, oral contraception and menstrual cycle article full-text available may plos one reiner sprengelmeyer jen lewis amanda c hahn david i perrett infant cuteness can influence adult-infant interaction and has been shown to activate reward centres in the brain. in a previous study, we found men and women to be differentially sensitive to small differences in infant facial cuteness, with reproductive hormone status as the potential underlying cause. it is unclear, however, whether reproductive hormone status impacts on the aesthetic and incentive salience of infant faces. to address this question, we conducted two interlinked studies. we used static images of the same smiling and neutral-looking infant faces in both a rating task, in which participants had to rate the cuteness of infant faces (aesthetic salience - ‘liking’), and a key-press task, in which participants could prolong or shorten viewing time of infant faces by rapid alternating key-presses (incentive salience - ‘wanting’). in a first study, we compared the performance of men, women who are taking oral contraceptives, and regularly cycling women. in this study, we found a significant correlation between cuteness ratings within and between groups, which implies that participants had the same concept of cuteness. cuteness ratings and effort to look at faces was linked regardless of sex and reproductive hormone status, in that cute faces were looked at for longer than less cute faces. a happy facial expression contributed only marginally to the incentive salience of the face. to explore the potential impact of reproductive hormone status in more detail, we followed a subset of regularly cycling women during the menstrual, follicular and luteal phases of their cycle. the aesthetic and incentive salience of infant faces did not change across the menstrual cycle. our findings suggest that reproductive hormone status does not modulate the aesthetic and incentive value of infant faces. view show abstract ... we combined a go/no-go task with a subsequent progressive-ratio key-press task (hodos, ). the key-press task operationalizes the amount of time and effort participants are willing to expend to view an image as a measure of its motivational incentive (aharon et al., ;levy et al., ). we expect that inhibition will decrease the motivational incentive of sexual images; thus, participants should execute fewer key-presses to see images of the sort previously encountered on no-go trials compared to those seen on prior go trials. ... hot or not: response inhibition reduces the hedonic value and motivational incentive of sexual stimuli article full-text available dec anne ferrey alexandra frischen mark james fenske the motivational incentive of reward-related stimuli can become so salient that it drives behavior at the cost of other needs. here we show that response inhibition applied during a go/no-go task not only impacts hedonic evaluations but also reduces the behavioral incentive of motivationally relevant stimuli. we first examined the impact of response inhibition on the hedonic value of sex stimuli associated with strong behavioral-approach responses (experiment ). sexually appealing and non-appealing images were both rated as less attractive when previously encountered as no-go (inhibited) than as go (non-inhibited) items. we then discovered that inhibition reduces the motivational incentive of sexual appealing stimuli (experiment ). prior go/no-go status affected the number of key-presses by heterosexual males to view erotic-female (sexually appealing) but not erotic-male or scrambled-control (non-appealing) images. these findings may provide a foundation for developing inhibition-based interventions to reduce the hedonic value and motivational incentive of stimuli associated with disorders of self-control. view show abstract ... this experiment utilized a keypress task to determine each subject's relative preference toward the ensemble of faces elman et al., ;strauss et al., ;levy et al., ;makris et al., ;perlis et al., ; figure | keypress paradigm. the behavioral task done outside the mri to minimize motor confounds to activation is schematized above, with an example raster plot below. ... age-related striatal bold changes without changes in behavioral loss aversion article full-text available apr front hum neurosci vijay viswanathan sang win lee jodi m gilman hans breiter loss aversion (la), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. the literature on aging and behavior suggests older individuals may show more la, although it is not clear if this is an effect of aging in general (as in the continuum from age and years), or of the state of older age (e.g., past age years). we also have not yet identified the potential biological effects of aging on the neural processing of la. in the current study we used a cohort of subjects with a year range of ages, and performed whole brain functional mri (fmri) to examine the ventral striatum/nucleus accumbens (vs/nac) response during a passive viewing of affective faces with model-based fmri analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. our a priori focus on the vs/nac was based on ( ) the vs/nac being a central region for reward/aversion processing; ( ) its activation to both positive and negative stimuli; ( ) its reported involvement with tracking la. la from approach/avoidance to affective faces showed excellent fidelity to published measures of la. imaging results were then compared to the behavioral measure of la using the same affective faces. although there was no relationship between age and la, we observed increasing neural differential sensitivity (nds) of the vs/nac to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. these findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same la behavior as in younger individuals, consistent with the idea of neural efficiency observed with high iq individuals showing less brain activation to complete the same task. view show abstract ... the present experiment was designed to test whether inhibition likewise affects the subsequent motivation to seek previously ignored stimuli. to this end, i employed a go/no-go inhibitory devaluation task combined with a progressive ratio key press task (hodos, ), which operationalizes the amount of work participants are willing to do in order to view an appealing image as a measure of the motivational salience of the stimulus (aharon et al., ;elman et al., ;levy et al., ;goddard, ). if inhibition decreases the motivational value of sexually appealing images, then participants should execute fewer key presses to see images of the sort previously encountered on no-go trials compared to those seen on prior go trials ... cognitive inhibition modifies the affective and incentive value of motivationally salient stimuli article jul anne ferrey view ... participants are willing to engage in effortful behavior in order to view attractive faces longer. for example, they perform more complicated or longer button presses (aharon et al., ;hayden et al., , study ;levy et al., ). males seem to be particularly rewarded by female attractiveness. ... mirror, mirror on the wall, who's the fairest one of all? influencing factors and effects of facial attractiveness. chapter full-text available jan gernot gerger helmut leder facial attractiveness influences us in a variety of ways. not only does it affect which partners we date, mate with or marry, but it also affects how we think about and interact with others. nearly everyone has experienced how stunning attractiveness captures the eye. and nearly everyone enjoys looking at attractive faces. moreover, advertisements of consumer products take advantage of the effects of facial attractiveness. the expectation here is that the positive effects of attractiveness would generalize to consumers’ product evaluations (baker and churchill, ). the preoccupation with attractiveness is also reflected in the considerable effort people put into looking attractive: “in the united states more money is spent on attractiveness than on education or social services” (etcoff, , p. ). thus, a multibillion-dollar industry lives off of the promise of increased attractiveness. it is, however, still unclear what the essence of facial attractiveness really is, but researchers have put considerable effort into revealing what, why and how different factors contribute to attractiveness. in the current chapter, we discuss what makes faces attractive and present some hypotheses on why this might be the case. we also show how our brains process attractiveness and how attractiveness affects various aspects of our experiences and behaviors. what is attractiveness? throughout this chapter, we use the term “attractiveness” to refer to the aesthetic qualities of faces. attractiveness is the most commonly used term in scientific studies. this common use of attractiveness is noteworthy because most people typically mention beauty, but not attractiveness, when discussing the aesthetic qualities of faces (augustin, wagemans and carbon, ). however, there might be some difference between beauty and attractiveness. beauty could refer more to aesthetic qualities of a face per se, while attractiveness could refer more to the function of aesthetic qualities of faces – indicating sexual and social qualities of potential mates (little, jones and debruine, ; senior, ; thornhill and gangestad, ). additionally, depending on the context, focusing on attractiveness might accentuate different aspects of aesthetic qualities of faces. in a mating context, for instance, sexual qualities might be considered more important for attractiveness evaluations, as compared to a non-mating context. importantly, when evaluating a face, these aspects yield different motivational and emotional consequences. thus, in our chapter, we will consider these aspects in the interpretation of results. view show abstract ... on the other hand, mdd males' high focused preference might facilitate a novel therapeutic approach in mdd. previous reports have shown that males generally show higher preference and motivation toward attractive opposite-sex faces , . attractive faces are easier for visual processing , suggesting that attractive appearance enhances the ability of mdd patients with impaired cognitive functioning or lowered motivation to be attracted. ... plasma acetylcholine and nicotinic acid are correlated with focused preference for photographed females in depressed males: an economic game study article full-text available jan hiroaki kubo daiki setoyama motoki watabe takahiro a. kato interpersonal difficulties are often observed in major depressive disorder (mdd), while the underlying psychological and biological mechanisms have not yet been elucidated. in the present case–control study, a pc-based trust game was conducted for drug-free mdd patients and healthy controls (hc). in the trust game, participants invested money in a partner (trusting behaviors), and also rated each partner’s attractiveness (preference for others). in addition, blood biomarkers including metabolites were measured. both mdd and hc males exhibited more trusting behaviors compared to females. mdd males’ preference for ordinary-attractive partners (lay-person photographs) was lower than hc males, whereas their preference for high-attractive females (fashion-model photographs) was similar levels to hc males. this tendency in mdd males could reflect a “focused (narrowed) preference for females”. as for blood biomarker analysis, the levels of metabolites including acetylcholine, amp, gmp, nicotinic acid and tryptophan were significantly different between two groups. interestingly, among male participants, acetylcholine and nicotinic acid were negatively correlated with the level of focused preference for photographed females. in sum, we have revealed some behavioral, psychological and biological traits of trusting behaviors and preference for others especially in mdd males. larger studies should be conducted to validate our preliminary findings. view show abstract ... aharon et al. ( ) stwierdzili, że mężczyźni dają wysokie oceny atrakcyjności niektórym twarzom kobiet i niektórym twarzom mężczyzn, ale jedynie w stosunku do atrakcyjnych twarzy kobiet mężczyzna zabiega o to, by je dłużej oglądać (w tym eksperymencie: wielokrotne naciskanie klawisza na klawiaturze powodowało dłuższe wyświetlanie twarzy na ekranie). levy et al. ( ) umożliwili badanym zarówno skracanie jak i wydłużanie czasu prezentacji twarzy i uzyskali następujące wyniki: (i) obie płcie nieco skracają czas dla twarzy (obu płci) o przeciętnej atrakcyjności, a silniedla twarzy nieatrakcyjnych, (ii) kobiety wydłużają czas dla atrakcyjnych twarzy obu płci, (iii) mężczyźni silnie wydłużają czas dla atrakcyjnych twarzy kobiecych, ale skracają dla atrakcyjnych twarzy męskich. możliwe, że chęć do oglądania atrakcyjnej twarzy odpowiada za "odmładzanie" proporcji twarzy (większe oczy, bardziej okrągłe oczy, wargi i twarz) na portretach i autoportretach (costa i corazza ). ... atrakcyjność twarzy ( ) research full-text available dec krzysztof kościński a newer version of the polish text which has been published (in somewhat shortened form) as two english-language papers: "facial attractiveness: general patterns of facial preferences" and "facial attractiveness: variation, adaptiveness and consequences of facial preferences". view show abstract ... as conducted in other studies using the ksog as a measure of sexual identity (blashill & powlishta, ;levy et al., ), participants in the present study rated their sexual identity as scores of (hetero/gay-lesbian/queer/non-heterosexual equally = . %), (gay-lesbian/queer/non-heterosexual somewhat more = . %), (gay-lesbian/queer/non-heterosexual mostly = . %), or (gay-lesbian/queer/non-heterosexual only = . %). ... confirmatory factor analyses of the body image-acceptance and action questionnaire and functionality appreciation scale among lgbq adults article full-text available nov zachary soulliard jillon s vander wal positive body image has been recognized as a construct that extends beyond evaluation of one’s physical appearance and instead focuses broadly on the love and respect people hold about their bodies. as a multidimensional construct, positive body image has been assessed via several different self-report measures. for example, body image flexibility and functionality appreciation refer to two aspects of positive body image that have been measured via the body image-acceptance and action questionnaire (bi-aaq) and functionality appreciation scale (fas). although the study of positive body image has expanded the body image and eating disorder literature, the majority of positive body image research, including the use of the bi-aaq and fas, has been conducted among presumably heterosexual participants. as such, it is unclear whether the factor structures of measures, such as the bi-aaq and fas, are supported among lesbian, gay, bisexual, and queer (lgbq) individuals. the purpose of the present study was to assess the factor structures of the bi-aaq and fas via confirmatory factor analyses among a sample of lgbq adults. based on a sample of self-identified lgbq participants recruited online, the factorial validity of the bi-aaq and fas were both generally supported with unitary factor structures, as have been found among presumably heterosexual samples. results suggest that the bi-aaq and fas may be used when assessing body image flexibility and functionality appreciation among lgbq individuals. future directions regarding body image flexibility and functionality appreciation measures among lgbq individuals are also discussed. view show abstract ... given that cognitive resources are limited, compared with allocating cognitive resources to ha male mates, allocating cognitive resources to competitive same-sex rivals makes more sense. therefore, evolutionary theory predicts that only ha female faces can capture attention from both men and women, and numerous results support this hypothesis (maner et al., (maner et al., , alevy et al., ;lovén et al., ). ... mechanisms for the cognitive processing of attractiveness in adult and infant faces: from the evolutionary perspective article full-text available mar qinhong xie taiyong bi hui kou research on the cognitive processing of facial attractiveness has mainly focused on adult faces. recent studies have revealed that the cognitive processing of facial attractiveness in infant faces is not the same as that in adult faces. therefore, it is necessary to summarize the evidence on the processing of facial attractiveness in each kind of face and compare their underlying mechanisms. in this paper, we first reviewed studies on the cognitive processing of facial attractiveness in adult faces, including attentional and mnemonic processing, and then discussed the underlying mechanisms. afterward, studies on facial attractiveness in infant faces were reviewed, and the underlying mechanisms were also discussed. direct comparisons between the two kinds of cognitive processing were subsequently made. the results showed that the mechanisms for the processing of attractiveness in adult faces and infant faces are mainly motivated by the perspectives of mate selection and raising offspring, respectively, in evolutionary psychology. finally, directions for future research are proposed. view show abstract ... for the present study, participants were asked to rate themselves based on a scale from to , where is heterosexual only and is gay/lesbian/queer/non-hetero only. similarly to other studies (blashill & powlishta, ;levy et al., ), participants were considered a sexual minority if they reported their identity between a (hetero/gay-lesbian/queer/non-hetero equally) and (gay-lesbian/queer/non-hetero only). participants were also asked to provide their height and weight in order to calculate their bmi, which was treated continuously in all analyses. ... validation of the body appreciation scale- and relationships to eating behaviors and health among sexual minorities article full-text available oct zachary soulliard jillon s vander wal although the study of positive body image continues to expand, researchers have predominantly focused the study of this newer construct among presumed heterosexual participants. the purpose of the present study was to examine the factor structure of a measure of positive body image, the body appreciation scale- (bas- ), among sexual minority participants. the present study also sought to psychometrically validate the bas- among sexual minorities by assessing its relationship with other facets of positive body image, including functionality appreciation and body image flexibility, as well as other related constructs, such as body dissatisfaction, disordered eating behaviors, intuitive eating behaviors, and physical and mental health. results from a confirmatory factor analysis of sexual minority adults (mage = . , sd = . ) indicated that the bas- displayed strong factorial validity with a unitary factor structure. furthermore, the bas- 's construct validity was supported based on correlations with other measures of positive body image, body dissatisfaction, and disordered eating behavior. results from this cross-sectional study supported a relationship between body appreciation and intuitive eating behaviors, as well as physical and mental health among sexual minority participants. these findings provide an initial understanding of body appreciation and other related constructs among sexual minority individuals. view show abstract ... for heterosexuals, opposite-sex faces stimulate assessment and reward brain systems, such as the amygdala, cingulate and insular cortices, more than same-sex faces, signifying they hold greater salience [ ]. both heterosexual men and women favor viewing attractive faces, but men willingly expend more effort to view beautiful women's than men's faces, while women spend less energy, and equivalent amounts, to view both beautiful men's and women's faces [ ]. men show slower response times to beautiful faces than women, evidencing greater cognitive load while processing attractive faces [ ]. ... perception and deception: human beauty and the brain article full-text available mar syst res behav sci daniel yarosh human physical characteristics and their perception by the brain are under pressure by natural selection to optimize reproductive success. men and women have different strategies to appear attractive and have different interests in identifying beauty in people. nevertheless, men and women from all cultures agree on who is and who is not attractive, and throughout the world attractive people show greater acquisition of resources and greater reproductive success than others. the brain employs at least three modules, composed of interconnected brain regions, to judge facial attractiveness: one for identification, one for interpretation and one for valuing. key elements that go into the judgment are age and health, as well as symmetry, averageness, face and body proportions, facial color and texture. these elements are all costly signals of reproductive fitness because they are difficult to fake. however, people deceive others using tricks such as coloring hair, cosmetics and clothing styles, while at the same time they also focus on detecting fakes. people may also deceive themselves, especially about their own attractiveness, and use self-signally actions to demonstrate to themselves their own true value. the neuroscience of beauty is best understood by considering the evolutionary pressures to maximize reproductive fitness. view show abstract ... van osch et al. ( ) showed that the group attractiveness effect occurs because observers only attend to a subset of the most attractive faces in the group. attractiveness is a salient visual cue (levy et al., ), and observers gaze longer at attractive than unattractive faces (maner et al., ;van osch et al., ). it is possible that selective attention toward the most attractive face in the group could cause the cheerleader effect. ... social perception in group scenes: social context modulates perceptions of facial attractiveness thesis full-text available dec daniel carragher despite the cautionary reminder to never “judge a book by its cover”, we regularly judge others based upon their facial appearance. far from meaning that we are all terribly judgmental, these trait impressions occur automatically. even though they are often not accurate, the trait judgments that we make about others can influence our own decision making. the candidate with the more “competent” face wins approximately % of national elections, and criminals with “untrustworthy” faces receive longer prison sentences for the same crimes than those with “trustworthy” faces. trait impressions have been the focus of research in the field of social perception since the earliest days of experimental psychology. while these studies have undoubtedly improved our understanding of the way that trait judgments are made from faces, the vast majority of these studies have been conducted by presenting observers with a single face at a time. however, we often meet people for the first time when they are surrounded by others, perhaps at a café or a bar. consequently, very little is known about the way we make trait impressions about an individual face that is seen among a group of other faces. within this thesis, i aimed to improve our understanding of the way that the facial attractiveness and trustworthiness of an individual is evaluated when they are seen among a group of other faces, compared to when they are seen alone. in the introduction to this thesis, i discuss the factors that influence the trustworthiness judgments that are made from the face, as well as the characteristics of faces that are perceived to be attractive. then, i describe the way that the visual system processes complex visual scenes, such as a group of faces, using a process called ensemble coding. bringing together these lines of research, i discuss “the cheerleader effect”, a phenomenon that is said to occur when the same face is perceived to be more attractive in a group compared to alone. the research in this thesis significantly advances our understanding of the cheerleader effect. my findings show that all individuals are perceived to be approximately . - % more attractive in a group than they are alone, regardless of how attractive they are, or how attractive the other group members are. i also show that the cheerleader effect does not extend to judgments of trustworthiness. crucially, my findings are also inconsistent with the hierarchical encoding mechanism that was initially proposed to cause the cheerleader effect, which was related to the way that the visual system uses ensemble coding to summarise groups of faces. based on the results contained within this thesis, i offer an alternative explanation for the cheerleader effect, which suggests that the effect might be related to the socially desirable characteristics that are attributed to individuals in groups. in conclusion, my findings demonstrate that social context reliably influences perceptions of facial attractiveness, and suggests that the field of social perception must be expanded to consider the influence of social context on the trait impressions that are made from the face. view show abstract ... since feminisation is associated with increased attractiveness, longer response times may reflect the intrinsic reward of attractiveness (aharon et al., ;leder, tinio, fuchs, & bohrn, ) to both male and female participants. in fact, similar findings, with no behavioural differences dependent on participant's sex, when assessing the attractiveness of both sex faces, have been reported in previous research (levy et al., ), namely in studies using eye-tracking (alexander & charles, ) and fmri (bray & o'doherty, ;kranz & ishai, ). ... event-related potentials modulated by the perception of sexual dimorphism: the influence of attractiveness and sex of faces article jun biol psychol mariana carrito pedro bem-haja carlos silva i.m. santos sexual dimorphism has been proposed as one of the facial traits to have evolved through sexual selection and to affect attractiveness perception. even with numerous studies documenting its effect on attractiveness and mate choice, the neurophysiological correlates of the perception of sexual dimorphism are not yet fully understood. in the present study, event-related potentials (erps) were recorded during visualisation of faces that had been previously transformed in shape to appear more masculine or more feminine. the participants' task consisted of judging the attractiveness of half of the total number of faces, and performing a sex discrimination task on the other half. both early and late potentials were modulated by the sex of faces, whereas the effect of the sexually dimorphic transform was mainly visible in the p (positive deflection around ms after stimulus onset), epn (early posterior negativity) and lpp (late positive potentials) components. there was an effect of sexual dimorphism on p and epn amplitudes when female participants visualised male faces, which may indicate that masculinity is particularly attended to when viewing opposite sex members. also, erp results seem to support the idea of sex differences in social categorisation decisions regarding faces, although differences were not evident on behavioural results. in general, these findings contribute to a better understanding of how humans perceive sexually dimorphic characteristics in other individuals' faces and how they affect attractiveness judgements. view show abstract ... by varying attractiveness. attractive faces elicit activity in regions associated with value processing(bray & o'doherty, ;roy, shohamy, & wager ;tsukiura & cabeza, ) and are motivationally significant: male participants will exert greater effort to view pictures of attractive female faces than unattractive female faces(aharon et al., ;levy et al., ), and stimuli that predict attractive (but not unattractive) female faces take on a positive conditioned value(bray & o'doherty, ). facial attractiveness can be assessed from minimal visual input, influences processing within ms, diverts attention from task-relevant information, and facilitates later memory(chen, liu & nakabayashi, ;maner et al., ; ... the role of value in the attentional boost effect article feb q j exp psychol khena m swallow stav atir focusing attention on one item typically interferes with the ability to process other information. yet, target detection can both facilitate memory for items paired with the target (the attentional boost effect) and increase the perceived value of those items (cued approach). because long-term memory is better for valuable items than for neutral items, we asked whether the attentional boost effect is due to changes in the perceived value of items that are paired with targets. in three experiments, participants memorised a series of briefly presented images that depicted valuable (e.g., food) or neutral (e.g., children's toys) items. whenever an item appeared, a square flashed in its centre. participants pressed a button if the square was a target colour but not if it was a distractor colour. consistent with previous research, target-paired items were remembered better than distractor-paired items and were rated as more valuable. importantly, if memory for target-paired items is enhanced because they increased in perceived value, then valuable items should have been better remembered than neutral items. however, we found no evidence that value enhanced memory for the items in this task. thus, it is unlikely that the attentional boost effect is due to changes in perceived value. view show abstract ... in the feedback motivation condition participants (all of whom were men) were shown a desirable picture of an attractive female as feedback for correct choices. as was shown in past research, men are motivated to exert effort to see faces of attractive women (levy et al., ). the pictures were chosen randomly without replacement from a large pool of such photographs. ... the influence of motivation on the use of unconscious information thesis full-text available jun maxim milyavsky most of our intuitive decisions are based on knowledge of which we are not completely aware (kahneman & klein, ). although unconscious knowledge probably plays an important role in our choices, it cannot be measured directly by introspection. thus, research must find alternative routes to assess the influence of unconscious information on subsequent mental products. a big challenge in studying this influence experimentally is establishing that one is not aware of the knowledge. subliminal stimulation is considered a touchstone in studies on unconscious processes as it allows for the most rigorous control of awareness (holender, ). researchers of subliminal stimulation ask the following fundamental questions: what kind of subliminal information can be processed? how deeply can it be processed? to what extent can it influence behavior? what are the determinants of its influence? so far, research has focused mainly on the first two questions, while relatively few studies have been conducted on the latter. in this work, i focused on the little-researched area of direct subliminal influence on choice. in particular, i asked whether achievement motivation can enhance the use of subliminal information on choice. a novel category-based choice (cbc) paradigm was developed to examine this question. in each trial of the cbc task, participants are asked to choose one of four category-labeled cards. the winning category is randomly determined in each trial, and if participants choose it they are rewarded. prior to choosing, participants are exposed to a subliminal prime. in half of the trials, this prime is a verbal cue – an exemplar from the winning category (e.g., category: fruits and cue: apple). in the other trials, the prime is a non-word control assigned to the winning category. since no other information predicting the winning category is provided, a better-than-chance rate of choosing the cued category indicates that the prime affects choice. the awareness of the prime is assessed in each trial both by subjective and objective tests. the cbc paradigm is distinguished from its predecessors in that it can measure the effect of semantic information on intuitive choices. the accuracy of these choices can then be compared to an objective standard (i.e. chance level) while the most conservative awareness tests are used. the influence of motivation and intention on use of subliminal cues in intuitive choice was tested in six experiments conducted within the framework of the cbc paradigm. experiments a and b examined whether subliminal semantic cues can be used in intuitive choice. they also tested one possible path of motivational influence: whether motivation can make some nodes in the mental lexicon more susceptible to subliminal stimulation. in order to examine this effect of motivation, the value of half of the categories was increased by assigning higher monetary rewards to accurate performance. the results of these experiments showed that subliminal cues indeed improved participants’ choices, thus establishing the basic effect of subliminally-presented word cues on intuitive choice. however, no effect of motivation was found. ii experiment tested whether achievement motivation can enhance the effect of subliminal cues on choice. unlike experiments a and b, which manipulated the incentives associated with specific categories, experiment assessed motivation by implicitly varying motivation levels between participants in two different ways: by ( ) priming concepts related to achievement and by ( ) giving slightly more attractive feedback for correct choices. findings showed that subliminal cues improved participants’ choices in the motivation conditions but not in the control condition even though participants were not aware of being in the motivational state. experiment was conducted in order to replicate the results of experiment and to test whether control participants would learn to use subliminal cues given more practice. therefore, the number of trials was doubled. the results replicated those of experiment and showed that given more practice, controls could obtain the effect of subliminal cues on choice too. experiment was conducted to extend the scope of the motivation effects found in experiments and to the domain of explicit motivation. motivation was increased by incentivizing certain trials with higher monetary rewards. experiment also examined the mechanism of motivational enhancement. specifically, for some participants, the type of trial (bonus or regular) was announced before, and for others, after the presentation of the cue. there were no bonus trials in the control condition. the findings showed that higher rewards enhanced conscious recognition of cues as well as the use of cues that were not consciously recognized in choice when the type of trial was announced before, but not after the presentation of the cues. the basic effect of the cues on choice was also obtained in the control condition. thus, the results showed that explicit motivation can enhance the influence of subliminal cues on choice and suggested that this effect stems from enhanced perceptual encoding of the cues. experiment aimed to replicate the effect of explicit motivation found in experiment , and thus the same method of inducing motivation was used. it also tested whether intentions can modulate the use of subliminal cues. specifically, the experiment tested whether intentions to avoid (vs. choose) could reduce the rate of choosing the subliminally cued alternative. this effect was found conditional on the motivational properties of the trial. it was obtained in the more valuable trials, but not in the less valuable trials, suggesting that motivation can enhance the effect of subliminal cues at the decision stage. the findings augment what we know about subliminal stimulation in three important directions. first, they show that subliminal semantic information from a wide spectrum of categories can improve intuitive decisions. second, they show that achievement motivation can modulate the use of subliminal cues even when people are not aware of being in a motivated state. third, they show that people’s intentions regarding how to use subliminal information affects the influence this information has on choice. view show abstract ... second, research has demonstrated that humans spend more time looking at faces that are considered attractive than at less attractive faces (e.g., aharon et al., ;shimojo et al., ;sui and liu, ;leder et al., ;chen et al., ). however, these effects are not the same in all individuals: compared to women, men exhibit a higher motivation to view attractive opposite-sex faces (levy et al., ;hahn et al., ) and are more likely to show attentional biases toward attractive opposite-sex stimuli (maner et al., (maner et al., , . ... behavioral and physiological bases of attentional biases: paradigms, participants, and stimuli book full-text available may sarah m sass wendy heller joscelyn e. fisher gregory a. miller view ... lawful equations characterizing preference with a keypress task were initially identified using visual stimuli (breiter and kim, ;kim et al., ;lee et al., ). the keypress task was developed out of a operant framework where each keypress action had an incremental consequence on stimulus view time lee et al., ), and has been well-validated across multiple studies elman et al., ;strauss et al., ;levy et al., ;makris et al., ;perlis et al., ;gasic et al., ;yamamoto et al., ;kim et al., ;lee et al., ;viswanathan et al., viswanathan et al., , . it follows an intrinsic motivation framework devoid of external rewards, such as food or money (deci and ryan, ;bandura, ), and quantifies reward/aversion by how much subjects approach or avoid stimuli-namely, to what extent subjects actively keypress to increase or decrease the amount of time they are exposed to predetermined categories of stimuli. ... keypress-based musical preference is both individual and lawful article full-text available may sherri lynn livengood john p. sheppard byoung woo kim hans breiter musical preference is highly individualized and is an area of active study to develop methods for its quantification. recently, preference-based behavior, associated with activity in brain reward circuitry, has been shown to follow lawful, quantifiable patterns, despite broad variation across individuals. these patterns, observed using a keypress paradigm with visual stimuli, form the basis for relative preference theory (rpt). here, we sought to determine if such patterns extend to non-visual domains (i.e., audition) and dynamic stimuli, potentially providing a method to supplement psychometric, physiological, and neuroimaging approaches to preference quantification. for this study, we adapted our keypress paradigm to two sets of stimuli consisting of seventeenth to twenty-first century western art music (classical) and twentieth to twenty-first century jazz and popular music (popular). we studied a pilot sample and then a separate primary experimental sample with this paradigm, and used iterative mathematical modeling to determine if rpt relationships were observed with high r fits. we further assessed the extent of heterogeneity in the rank ordering of keypress-based responses across subjects. as expected, individual rank orderings of preferences were quite heterogeneous, yet we observed mathematical patterns fitting these data similar to those observed previously with visual stimuli. these patterns in music preference were recurrent across two cohorts and two stimulus sets, and scaled between individual and group data, adhering to the requirements for lawfulness. our findings suggest a general neuroscience framework that predicts human approach/avoidance behavior, while also allowing for individual differences and the broad diversity of human choices; the resulting framework may offer novel approaches to advancing music neuroscience, or its applications to medicine and recommendation systems. view show abstract ... of note, the pattern of men's and women's response to sexual stimuli of their preferred and non-preferred gender appears to extend to male and female facial images, with androphilic women showing similar viewing times of both beautiful male and female faces, and gynephilic men showing longer viewing times for beautiful female than male faces ( [ , , ]; but see also [ ], and [ ], for other findings). these results further support the notion of response specificity to the preferred sexual target for men, but not for women. ... to each its own? gender differences in affective, autonomic, and behavioral responses to same-sex and opposite-sex visual sexual stimuli article jan physiol behav michela sarlo giulia buodo a large body of research on gender differences in response to erotic stimuli has focused on genital and/or subjective sexual arousal. on the other hand, studies assessing gender differences in emotional psychophysiological responding to sexual stimuli have only employed erotic pictures of male-female couples or female/male nudes. the present study aimed at investigating differences between gynephilic men and androphilic women in emotional responding to visual sexual stimuli depicting female-male, female-female and male-male couples. affective responses were explored in multiple response systems, including autonomic indices of emotional activation, i.e., heart rate and skin conductance, along with standardized measures of valence and arousal. blood pressure was measured as an index of autonomic activation associated with sexual arousal, and free viewing times as an index of interest/avoidance. overall, men showed gender-specific activation characterized by clearly appetitive reactions to the target of their sexual attraction (i.e., women), with physiological arousal discriminating female-female stimuli as the most effective sexual cues. in contrast, women's emotional activation to sexual stimuli was clearly non-specific in most of the considered variables, with the notable exception of the self-report measures. overall, affective responses replicate patterns of gender-specific and gender-nonspecific sexual responses in gynephilic men and androphilic women. view show abstract ... locke introduced motivation as one of the steps for achieving communication effectiveness (locke, ). scott insisted that without a sufficient level of motivation, communication may not be successful (scott, ). anthony and govindarajan though, showed that a company must increase motivation through development the communication to improve decisions and financial success (anthony and govindarajan, ). ... relationships among strategic management, strategic behaviors, emotional intelligence, it-business strategic alignment, motivation, and communication effectiveness article full-text available oct hashim fauzy yaacob ishak mad shah hassan jorfi saeid jorfi in today's strategic management, motivation in organizations of iran plays a main role in relationship between emotional intelligence and communication effectiveness. the paper is undertaken to understand the strategic behavior and motivation with relationship between managers' emotional intelligence and employees to improve communication effectiveness in organizations of iran. data (n= ) for this study were collected through questionnaires that participants were managers and employees of educational administrations and agricultural bank of iran. the aim of this paper assesses the emotional intelligence with communication effectiveness and motivation as moderator in educational administrations and agricultural bank of iran. strategic management plays an important role in strategic behaviors of managers and employees in organizations. further, on the other hand, strategic management has a positive relationship with strategic alignment and strategic alignment can impact motivation in this study. effective strategic alignment has a positive effect on the motivation of managers and employees in organizations of iran. additionally emotional intelligence influenced by strategic behavior in this relationship. the result of the paper shows a strong correspondence between motivation with the relationship between emotional intelligence and communication effectiveness. also strategic management has a positive relationship with strategic behavior; on the other hand, relationship with strategic alignment that can influence view show abstract ... this experiment utilized a keypress task to determine each subject's relative preference toward the ensemble of faces elman et al., ;strauss et al., ;levy et al., ;makris et al., ;perlis et al., ; figure | keypress paradigm. the behavioral task done outside the mri to minimize motor confounds to activation is schematized above, with an example raster plot below. ... using fmri analysis to unpack a portion of prospect theory for advertising/marketing understanding chapter jan don schultz martin p. block fengqing (zoe) zhang vijay viswanathan one of the key elements being used today to support/reject/enhance marketing/advertising theory is kahneman and tversky’s prospect theory ( ). interest has been growing on how that concept might support/explain how advertising “works” based on kahneman’s later concepts as found in his text “thinking fast and slow” ( ). all have spawned and supported the field of behavioral economics (kahneman, american economic review, : – , ). literally thousands of discussions, speculations, hypotheses, and applications of these concepts can now be found in the advertising literature. yet, in spite of its broad industry and practitioner acceptance, the basic fundamentals of prospect theory, as kahneman and tversky outlined them in their original paper, “prospect theory: an analysis of decision under risk” ( ), and their follow-on book, “choices, values and frames” ( ) still rely mostly on support from small scale, academic, laboratory experiments based on questionnaires and researcher interpretations. we employ the new tools of fmri in an age-related experiment. loss aversion has a long history in marketing and communication theory and the ability to connect or refute that concept to aging in marketing theory would seem a major aid to marketers going forward. view show abstract ... even though, some consideration should be given to its limitations and future prospects. first, it was not possible to evaluate gender difference due to the unbalanced sample in the present study, though some research suggests that this factor affects behavior (levy et al., ). therefore, future research should disentangle the gender influence. ... effect of affective personality information on face processing: evidence from erps article full-text available may qiuling luo wang hanlin m. dzhelyova lei mo this study tested the extent to which there are neural correlates of the influence of affective personality information on face processing, using event-related potentials (erps). in the learning phase, participants viewed a target individual’s face (with a neutral expression or faint smile) paired with negative, neutral or positive sentences describing the target’s previous typical behavior. in the following eeg testing phase, participants completed gender judgments of the learned faces. statistical analyses were conducted on measures of neural activity during the gender judgment task. repeated measures anova of erp data showed that faces described as having a negative personality elicited larger n than did those with a neutral or positive description. the early posterior negativity (epn) showed the same pattern, with larger amplitudes for faces paired with negative personality than for others. the size of the late positive potential (lpp) was larger for faces paired with positive personality than for those with neutral and negative personality. the current study indicates that affective personality information is associated with an automatic, top-down modulation of face processing. view show abstract a different pattern of lateralised brain activity during processing of loved faces in men and women: a meg study article oct biol psychol klaus m. beier hannes o tiedt andreas lueschow joachim e weber viewing personally familiar and loved faces evokes a distinct pattern of brain activity as demonstrated by research employing imaging and electrophysiological methods. the aim of the current investigation was to study the perception of loved faces combined with recalling past emotional experiences using whole-head magnetoencephalograpy (meg). twenty-eight participants (fourteen female) viewed photographs of their romantic partner as well as of two long-term friends while imagining a positive emotional encounter with the respective person. face-stimuli evoked a slow and sustained shift of magnetic activity from ms post-stimulus onwards which differentiated loved from friends' faces in female participants and left-sided sensors only. this late-latency evoked magnetic field resembled (as its magnetic counterpart) erp-modulations by affective content and memory, most notably the late positive potential (lpp). we discuss our findings in the light of studies suggesting greater responsiveness to affective cues in women as well as sex differences in autobiographical and emotional memory. view show abstract applications of signaling theory to contemporary human courtship article bria lane dunham view influential factors of facial attractiveness: the observer hypothesis article full-text available dec hui kou yanhua su yan zhang hong chen view seeing faces chapter jan david i perrett view facial attractiveness: variation, adaptiveness and consequences of facial preferences article full-text available jan krzysztof kościński facial attractiveness: variation, adaptiveness and consequences of facial preferences this review embraces the following topics: intra- and inter-populational variation of facial preferences, relationship between facial attractiveness and mate value, biological and social effects of the perception of facial attractiveness, credibility of the adaptive perspective on facial preferences, and the phylogeny of facial attractiveness. its main conclusions are as follows: ( ) many sources of inter-individual variation in assessments of facial attractiveness have been identified, e.g., the age, sex, biological quality, physiological state, personality, and living situation of the judge, as well as previously observed faces, physical similarity of the focal face to the judge's face, and acquaintance with and knowledge of the face owner. ( ) inter-populational consistency in perception of facial attractiveness is substantial and possesses both a biological and a cultural basis. ( ) facial attractiveness is a reliable cue to biological quality of the face owner, e.g., better parasite resistance, physical fitness, reproductive fitness, longevity, less mutational load, higher intelligence and better mental health. ( ) facially attractive people have more sexual partners, marry at a younger age, and remain single less frequently. thereby, they have higher reproductive success than unattractive individuals. ( ) as a whole, research supports the thesis that facial preferences are adaptive, that is, they evolved during the course of biological evolution because they assisted an individual in choosing a mate with good genes or a good personality. view show abstract beauty captures the attention of the beholder article oct annukka k lindell kaarina l. lindell humans are exquisitely sensitive to beauty: it plays a primary role in impression formation and influences subsequent judgements, favouring the beautiful. why? this paper examines the factors underlying beauty's effect on the mind of the beholder. first we review the evolutionary importance of beauty, including its role as reward, before focusing on the impact of beauty on attention and the influence of motivational state. the research reviewed demonstrates the evolutionary importance of beauty as an implicit cue indexing genotypic and phenotypic quality: as a preference for beauty is highly adaptive, the brain has evolved to activate neural networks associated with reward in response to beautiful faces (e.g., orbitofrontal cortex, nucleus accumbens, ventral striatum). not surprisingly then, beauty holds privileged attentional status: even when attention is consciously engaged elsewhere, beauty alters attentional deployment rapidly, effortlessly and unconsciously, capturing attention even when beauty falls outside the focus of conscious attention or a region of high visual acuity. motivational context also influences attentional adhesion to beauty, with perceiver gender, relationship status and sociosexual orientation all influencing attentional capture. overall, the research confirms that beauty holds privileged attentional status, in keeping with its evolutionary importance; beauty truly does capture the mind of the beholder. view show abstract attractive faces are rewarding irrespective of face category: motivation in viewing attractive faces in japanese viewers conference paper full-text available jan maiko kobayashi katsumi watanabe koyo nakamura view changes in lower facial height and facial esthetics with incremental increases in occlusal vertical dimension in dentate subjects article jul int j prosthodont orenstein, noah philip, dmd avinash s bidra john r agar mark d little to determine if there are objective changes in lower facial height and subjective changes in facial esthetics with incremental increases in occlusal vertical dimension in dentate subjects. twenty subjects of four different races and both sexes with a class i dental occlusion had custom diagnostic occlusal prostheses (mandibular overlays) fabricated on casts mounted on a semi-adjustable articulator. the overlays were fabricated at -mm, -mm, -mm, and -mm openings of the anterior guide pin of a semi-adjustable articulator. direct facial measurements were made between pronasale and menton on each subject while wearing the four different overlays. thereafter, two digital photographs (frontal and profile) were taken for each subject at maximum intercuspation (baseline) and wearing each of the four mandibular overlays. the photographs of eight subjects were standardized and displayed in a random order to judges comprising laypeople, general dentists, and prosthodontists. using a visual analog scale, each judge was asked to rate the facial esthetics twice for each of the images. for objective changes, although an anterior guide pin-lower facial height relationship of : . mm was observed, the findings were not correlated (p > . ). for subjective changes, the visual analog scale ratings of judges were uncorrelated with increases in anterior guide pin opening up to mm, irrespective of the judge's background status or the sexes of the judges or the subjects (p > . ). incremental increases in anterior guide pin opening up to mm did not correlate to similar increases in lower facial height. additionally, it made no difference in a judge's evaluation of facial esthetics irrespective of the judge's background status (layperson, general dentist, or prosthodontist) or sex. view show abstract attractive faces are rewarding irrespective of face category motivation in viewing attractive faces in japanese viewers article full-text available jan maiko kobayashi koyo nakamura katsumi watanabe view show more dominance and heterosexual attraction article full-text available apr j pers soc psychol edward k. sadalla douglas t. kenrick beth vershure four experiments examined the relation between behavioral expressions of dominance and the heterosexual attractiveness of males and females. predictions concerning the relation between dominance and heterosexual attraction were derived from a consideration of sex role norms and from the comparative biological literature. all four experiments indicated an interaction between dominance and sex of target. dominance behavior increased the attractiveness of males, but had no effect on the attractiveness of females. the third study indicated that the effect did not depend on the sex of the rater or on the sex of those with whom the dominant target interacted. the fourth study showed that the effect was specific to dominance as an independent variable and did not occur for related constructs (aggressive or domineering). this study also found that manipulated dominance enhanced only a male's sexual attractiveness and not his general likability. the results were discussed in terms of potential biological and cultural causal mechanisms. (psycinfo database record (c) apa, all rights reserved) view show abstract buss, david m. . “sex differences in human mate preferences: evolutionary hypotheses tested in cultures.” behavioral and brain sciences article full-text available mar behav brain sci david m buss contemporary mate preferences can provide important clues to human reproductive history. little is known about which characteristics people value in potential mates. five predictions were made about sex differences in human mate preferences based on evolutionary conceptions of parental investment, sexual selection, human reproductive capacity, and sexual asymmetries regarding certainty of paternity versus maternity. the predictions centered on how each sex valued earning capacity, ambition— industriousness, youth, physical attractiveness, and chastity. predictions were tested in data from samples drawn from countries located on six continents and five islands (total n = , ). for countries, demographic data on actual age at marriage provided a validity check on questionnaire data. females were found to value cues to resource acquisition in potential mates more highly than males. characteristics signaling reproductive capacity were valued more by males than by females. these sex differences may reflect different evolutionary selection pressures on human males and females; they provide powerful cross-cultural evidence of current sex differences in reproductive strategies. discussion focuses on proximate mechanisms underlying mate preferences, consequences for human intrasexual competition, and the limitations of this study. view show abstract sexual strategies theory: an evolutionary perspective on human mating article full-text available may psychol rev david m buss david schmitt this article proposes a contextual-evolutionary theory of human mating strategies. both men and women are hypothesized to have evolved distinct psychological mechanisms that underlie short-term and long-term strategies. men and women confront different adaptive problems in short-term as opposed to long-term mating contexts. consequently, different mate preferences become activated from their strategic repertoires. nine key hypotheses and predictions from sexual strategies theory are outlined and tested empirically. adaptive problems sensitive to context include sexual accessibility, fertility assessment, commitment seeking and avoidance, immediate and enduring resource procurement, paternity certainty, assessment of mate value, and parental investment. discussion summarizes additional sources of behavioral data, outlines adaptive problems common to both sexes, and suggests additional contexts likely to cause shifts in mating strategy. view show abstract biobehavioral responses to stress in females: tend-and-befriend, not fight-or-flight article full-text available aug psychol rev shelley taylor laura cousino klein brian p. lewis john a updegraff the human stress response has been characterized, both physiologically and behaviorally, as "fight-or-flight." although fight-or-flight may characterize the primary physiological responses to stress for both males and females, we propose that, behaviorally, females' responses are more marked by a pattern of "tend-and-befriend." tending involves nurturant activities designed to protect the self and offspring that promote safety and reduce distress; befriending is the creation and maintenance of social networks that may aid in this process. the biobehavioral mechanism that underlies the tend-and-befriend pattern appears to draw on the attachment-caregiving system, and neuroendocrine evidence from animal and human studies suggests that oxytocin, in conjunction with female reproductive hormones and endogenous opioid peptide mechanisms, may be at its core. this previously unexplored stress regulatory system has manifold implications for the study of stress. view show abstract saper cb, chou tc, elmquist jk. the need to feed: homeostatic and hedonic control of eating. neuron : - article full-text available nov neuron clifford b. saper thomas c jhou joel k elmquist feeding provides substrate for energy metabolism, which is vital to the survival of every living animal and therefore is subject to intense regulation by brain homeostatic and hedonic systems. over the last decade, our understanding of the circuits and molecules involved in this process has changed dramatically, in large part due to the availability of animal models with genetic lesions. in this review, we examine the role played in homeostatic regulation of feeding by systemic mediators such as leptin and ghrelin, which act on brain systems utilizing neuropeptide y, agouti-related peptide, melanocortins, orexins, and melanin concentrating hormone, among other mediators. we also examine the mechanisms for taste and reward systems that provide food with its intrinsically reinforcing properties and explore the links between the homeostatic and hedonic systems that ensure intake of adequate nutrition. view show abstract what does sexual orientation orient? a biobehavioral model distinguishing romantic love and sexual desire article full-text available feb psychol rev lisa diamond although it is typically presumed that heterosexual individuals only fall in love with other-gender partners and gay-lesbian individuals only fall in love with same-gender partners, this is not always so. the author develops a biobehavioral model of love and desire to explain why. the model specifies that (a) the evolved processes underlying sexual desire and affectional bonding are functionally independent; (b) the processes underlying affectional bonding are not intrinsically oriented toward other-gender or same-gender partners: (c) the biobehavioral links between love and desire are bidirectional, particularly among women. these claims are supported by social-psychological, historical, and cross-cultural research on human love and sexuality as well as by evidence regarding the evolved biobehavioral mechanisms underlying mammalian mating and social bonding. view show abstract unconscious affective reactions to masked happy versus angry faces influence consumption behavior and judgments of value article full-text available feb pers soc psychol bull piotr winkielman kent c berridge julia wilbarger the authors explored three properties of basic, unconsciously triggered affective reactions: they can influence consequential behavior, they work without eliciting conscious feelings, and they interact with motivation. the authors investigated these properties by testing the influence of subliminally presented happy versus angry faces on pouring and consumption of beverage (study ), perception of beverage value (study ), and reports of conscious feelings (both studies). consistent with incentive motivation theory, the impact of affective primes on beverage value and consumption was strongest for thirsty participants. subliminal smiles caused thirsty participants to pour and consume more beverage (study ) and increased their willingness to pay and their wanting more beverage (study ). subliminal frowns had the opposite effect. no feeling changes were observed, even in thirsty participants. the results suggest that basic affective reactions can be unconscious and interact with incentive motivation to influence assessment of value and behavior toward valenced objects. view show abstract the neural basis of addiction: a pathology of motivation and choice article full-text available sep am j psychiat peter w kalivas nora d volkow a primary behavioral pathology in drug addiction is the overpowering motivational strength and decreased ability to control the desire to obtain drugs. in this review the authors explore how advances in neurobiology are approaching an understanding of the cellular and circuitry underpinnings of addiction, and they describe the novel pharmacotherapeutic targets emerging from this understanding. findings from neuroimaging of addicts are integrated with cellular studies in animal models of drug seeking. while dopamine is critical for acute reward and initiation of addiction, end-stage addiction results primarily from cellular adaptations in anterior cingulate and orbitofrontal glutamatergic projections to the nucleus accumbens. pathophysiological plasticity in excitatory transmission reduces the capacity of the prefrontal cortex to initiate behaviors in response to biological rewards and to provide executive control over drug seeking. simultaneously, the prefrontal cortex is hyperresponsive to stimuli predicting drug availability, resulting in supraphysiological glutamatergic drive in the nucleus accumbens, where excitatory synapses have a reduced capacity to regulate neurotransmission. cellular adaptations in prefrontal glutamatergic innervation of the accumbens promote the compulsive character of drug seeking in addicts by decreasing the value of natural rewards, diminishing cognitive control (choice), and enhancing glutamatergic drive in response to drug-associated stimuli. view show abstract food intake and reward mechanisms in patients with schizophrenia: implications for metabolic disturbances and treatment with second-generation antipsychotic agents article full-text available nov neuropsychopharmacol igor elman david borsook scott e lukas obesity is highly prevalent among patients with schizophrenia and is associated with detrimental health consequences. although excessive consumption of fast food and pharmacotherapy with such second-generation antipsychotic agents (sgas) as clozapine and olanzapine has been implicated in the schizophrenia/obesity comorbidity, the pathophysiology of this link remains unclear. here, we propose a mechanism based on brain reward function, a relevant etiologic factor in both schizophrenia and overeating. a comprehensive literature search on neurobiology of schizophrenia and of eating behavior was performed. the collected articles were critically reviewed and relevant data were extracted and summarized within four key areas: ( ) energy homeostasis, ( ) food reward and hedonics, ( ) reward function in schizophrenia, and ( ) metabolic effects of the sgas. a mesolimbic hyperdopaminergic state may render motivational/incentive reward system insensitive to low salience/palatability food. this, together with poor cognitive control from hypofunctional prefrontal cortex and enhanced hedonic impact of food, owing to exaggerated opioidergic drive (clinically manifested as pain insensitivity), may underlie unhealthy eating habits in patients with schizophrenia. treatment with sgas purportedly improves dopamine-mediated reward aspects, but at the cost of increased appetite and worsened or at least not improved opiodergic capacity. these effects can further deteriorate eating patterns. pathophysiological and therapeutic implications of these insights need further validation via prospective clinical trials and neuroimaging studies. view show abstract sex, beauty and the orbitofrontal cortex article full-text available mar int j psychophysiol alumit ishai face perception is mediated by a distributed neural system in the human brain. attention, memory and emotion modulate the neural activation evoked by faces, however the effects of gender and sexual orientation are currently unknown. to test whether subjects would respond more to their sexually-preferred faces, we scanned hetero- and homosexual men and women whilst they assessed facial attractiveness. behaviorally, regardless of their gender and sexual orientation, all subjects similarly rated the attractiveness of both male and female faces. consistent with our hypothesis, a three-way interaction between stimulus gender, beauty and the sexual preference of the subject was found in the medial orbitofrontal cortex (ofc). in heterosexual women and homosexual men, attractive male faces elicited stronger activation than attractive female faces, whereas in heterosexual men and homosexual women, attractive female faces evoked stronger activation than attractive male faces. these findings suggest that the ofc represents the value of salient sexually-relevant faces, irrespective of their reproductive fitness. view show abstract neural coding of reward-prediction error signals during classical conditioning with attractive faces article full-text available may j neurophysiol signe bray john p o'doherty attractive faces can be considered to be a form of visual reward. previous imaging studies have reported activity in reward structures including orbitofrontal cortex and nucleus accumbens during presentation of attractive faces. given that these stimuli appear to act as rewards, we set out to explore whether it was possible to establish conditioning in human subjects by pairing presentation of arbitrary affectively neutral stimuli with subsequent presentation of attractive and unattractive faces. furthermore, we scanned human subjects with functional magnetic resonance imaging (fmri) while they underwent this conditioning procedure to determine whether a reward-prediction error signal is engaged during learning with attractive faces as is known to be the case for learning with other types of reward such as juice and money. subjects showed changes in behavioral ratings to the conditioned stimuli (cs) when comparing post- to preconditioning evaluations, notably for those css paired with attractive female faces. we used a simple rescorla-wagner learning model to generate a reward-prediction error signal and entered this into a regression analysis with the fmri data. we found significant prediction error-related activity in the ventral striatum during conditioning with attractive compared with unattractive faces. these findings suggest that an arbitrary stimulus can acquire conditioned value by being paired with pleasant visual stimuli just as with other types of reward such as money or juice. this learning process elicits a reward-prediction error signal in a main target structure of dopamine neurons: the ventral striatum. the findings we describe here may provide insights into the neural mechanisms tapped into by advertisers seeking to influence behavioral preferences by repeatedly exposing consumers to simple associations between products and rewarding visual stimuli such as pretty faces. view show abstract the debate over dopamine's role in reward: the case for incentive salience article apr psychopharmacology kent c berridge introduction: debate continues over the precise causal contribution made by mesolimbic dopamine systems to reward. there are three competing explanatory categories: 'liking', learning, and 'wanting'. does dopamine mostly mediate the hedonic impact of reward ('liking')? does it instead mediate learned predictions of future reward, prediction error teaching signals and stamp in associative links (learning)? or does dopamine motivate the pursuit of rewards by attributing incentive salience to reward-related stimuli ('wanting')? each hypothesis is evaluated here, and it is suggested that the incentive salience or 'wanting' hypothesis of dopamine function may be consistent with more evidence than either learning or 'liking'. in brief, recent evidence indicates that dopamine is neither necessary nor sufficient to mediate changes in hedonic 'liking' for sensory pleasures. other recent evidence indicates that dopamine is not needed for new learning, and not sufficient to directly mediate learning by causing teaching or prediction signals. by contrast, growing evidence indicates that dopamine does contribute causally to incentive salience. dopamine appears necessary for normal 'wanting', and dopamine activation can be sufficient to enhance cue-triggered incentive salience. drugs of abuse that promote dopamine signals short circuit and sensitize dynamic mesolimbic mechanisms that evolved to attribute incentive salience to rewards. such drugs interact with incentive salience integrations of pavlovian associative information with physiological state signals. that interaction sets the stage to cause compulsive 'wanting' in addiction, but also provides opportunities for experiments to disentangle 'wanting', 'liking', and learning hypotheses. results from studies that exploited those opportunities are described here. conclusion: in short, dopamine's contribution appears to be chiefly to cause 'wanting' for hedonic rewards, more than 'liking' or learning for those rewards. view show abstract attitudes toward handicapped children: article jan phys occup ther pediatr elnora m. gilfoyle jeffrey a. gliner positive attitudes toward handicapped children are paramount for success in mainstreaming. in this study, attitude change toward handicapped children as judged by their nonhangicapped peers were investigated. an educational puppet show was used as the independent variable in this study. results as measured by pre-to-post test changes on a visual analogue scale, demonstrated significant increase in students' information gain about handicapped peers; however, items suggesting personal feelings and behavior were not altered. furthermore, a stable order of preference toward the physically handicapped remained on the post test. implication from this study indicate the important of long term structured learning experience and direct contact as necessary variables for attitude change toward the handicapped. view show abstract the descent of man and selection in relation to sex article jan charles r. darwin in the current resurgence of interest in the biological basis of animal behavior and social organization, the ideas and questions pursued by charles darwin remain fresh and insightful. this is especially true of the descent of man and selection in relation to sex, darwin's second most important work. this edition is a facsimile reprint of the first printing of the first edition ( ), not previously available in paperback. the work is divided into two parts. part one marshals behavioral and morphological evidence to argue that humans evolved from other animals. darwin shoes that human mental and emotional capacities, far from making human beings unique, are evidence of an animal origin and evolutionary development. part two is an extended discussion of the differences between the sexes of many species and how they arose as a result of selection. here darwin lays the foundation for much contemporary research by arguing that many characteristics of animals have evolved not in response to the selective pressures exerted by their physical and biological environment, but rather to confer an advantage in sexual competition. these two themes are drawn together in two final chapters on the role of sexual selection in humans. in their introduction, professors bonner and may discuss the place of the descent in its own time and relation to current work in biology and other disciplines. view show abstract civilization and its discontents article jan sigmund freud view measuring the physical in physical attractiveness. quasi-experiments on the sociobiology of female facial beauty article may j pers soc psychol michael cunningham investigated, in quasi-experiments, the relation between specific adult female facial features and the attraction, attribution, and altruistic responses of adult males. precise measurements were obtained of the relative size of facial features in an international sample of photographs of females. undergraduate males provided ratings of the attractiveness of each of the females. positively correlated with attractiveness ratings were the neonate features of large eyes, small nose, and small chin; the maturity features of prominent cheekbones and narrow cheeks; and the expressive features of high eyebrows, large pupils, and large smile. a nd study asked males to rate the personal characteristics of previously measured females. the males were also asked to indicate the females for whom they would be most inclined to perform altruistic behaviors and to select for dating, sexual behavior, and childrearing. the nd study replicated the correlations of feature measurements with attractiveness. facial features also predicted personality attributions, altruistic inclinations, and reproductive interest. sociobiological interpretations are discussed. ( ref) (psycinfo database record (c) apa, all rights reserved) view show abstract structured clinical interview for dsm-iv-tr axis i disorders, research version, non-patient edition chapter jan michael b first robert l. spitzer m gibbon janet b w williams view the evolution of human sexuality revisited book jan behav brain sci donald symons patterns in the data on human sexuality support the hypothesis that the bases of sexual emotions are products of natural selection. most generally, the universal existence of laws, rules, and gossip about sex, the pervasive interest in other people's sex lives, the widespread seeking of privacy for sexual intercourse, and the secrecy that normally permeates sexual conduct imply a history of reproductive competition. more specifically, the typical differences between men and women in sexual feelings can be explained most parsimoniously as resulting from the extraordinarily different reproductive opportunities and constraints males and females normally encountered during the course of evolutionary history. men are more likely than women to desire multiple mates; to desire a variety of sexual partners; to experience sexual jealousy of a spouse irrespective of specific circumstances; to be sexually aroused by the sight of a member of the other sex; to experience an autonomous desire for sexual intercourse; and to evaluate sexual desirability primarily on the bases of physical appearance and youth. the evolutionary causes of human sexuality have been obscured by attempts to find harmony in natural creative processes and human social life and to view sex differences as complementary. the human female's capacity for orgasm and the loss of estrus, for example, have been persistently interpreted as marriage-maintaining adaptations. available evidence is more consistent with the view that few sex differences in sexuality are complementary, that many aspects of sexuality undermine marriage, and that sexuality is less a unifying than a divisive force in human affairs. view show abstract sexual orientation: a multivariate dynamic process. journal of homosexuality, , - article feb j homosexual fritz klein barry sepekoff timothy j. wolf theory and research concerning sexual orientation has been restricted in its scope and influence by the lack of clear and widely accepted definitions of terms like heterosexual, bisexual, and homosexual. in an attempt to better demarcate and understand the complexities of human sexual attitudes, emotions, and behavior, the klein sexual orientation grid (ksog) was developed and administered. the ksog is composed of seven variables that are dimensions of sexual orientation, each of which is rated by the subject as applying to the present, past, or ideal. analysis of the data from subjects who filled out the ksog in forum magazine indicated that the instrument was a reliable and valid research tool which took into consideration the multi-variable and dynamic aspects of sexual orientation. view show abstract beautiful faces have variable reward value: fmri and behavioral evidence. article dec neuron itzhak aharon nancy l etcoff dan ariely hans breiter the brain circuitry processing rewarding and aversive stimuli is hypothesized to be at the core of motivated behavior. in this study, discrete categories of beautiful faces are shown to have differing reward values and to differentially activate reward circuitry in human subjects. in particular, young heterosexual males rate pictures of beautiful males and females as attractive, but exert effort via a keypress procedure only to view pictures of attractive females. functional magnetic resonance imaging at t shows that passive viewing of beautiful female faces activates reward circuitry, in particular the nucleus accumbens. an extended set of subcortical and paralimbic reward regions also appear to follow aspects of the keypress rather than the rating procedures, suggesting that reward circuitry function does not include aesthetic assessment. view show abstract o'doherty j, winston j, critchley h, perrett d, burt dm, dolan rj. beauty in a smile: the role of medial orbitofrontal cortex in facial attractiveness. neuropsychologia : - article feb neuropsychologia john p o'doherty joel s winston hugo critchley raymond j dolan the attractiveness of a face is a highly salient social signal, influencing mate choice and other social judgements. in this study, we used event-related functional magnetic resonance imaging (fmri) to investigate brain regions that respond to attractive faces which manifested either a neutral or mildly happy face expression. attractive faces produced activation of medial orbitofrontal cortex (ofc), a region involved in representing stimulus-reward value. responses in this region were further enhanced by a smiling facial expression, suggesting that the reward value of an attractive face as indexed by medial ofc activity is modulated by a perceiver directed smile. view show abstract psychosis as a state of aberrant salience: a framework linking biology, phenomenology, and pharmacology in schizophrenia article feb am j psychiat shitij kapur the clinical hallmark of schizophrenia is psychosis. the objective of this overview is to link the neurobiology (brain), the phenomenological experience (mind), and pharmacological aspects of psychosis-in-schizophrenia into a unitary framework. current ideas regarding the neurobiology and phenomenology of psychosis and schizophrenia, the role of dopamine, and the mechanism of action of antipsychotic medication were integrated to develop this framework. a central role of dopamine is to mediate the "salience" of environmental events and internal representations. it is proposed that a dysregulated, hyperdopaminergic state, at a "brain" level of description and analysis, leads to an aberrant assignment of salience to the elements of one's experience, at a "mind" level. delusions are a cognitive effort by the patient to make sense of these aberrantly salient experiences, whereas hallucinations reflect a direct experience of the aberrant salience of internal representations. antipsychotics "dampen the salience" of these abnormal experiences and by doing so permit the resolution of symptoms. the antipsychotics do not erase the symptoms but provide the platform for a process of psychological resolution. however, if antipsychotic treatment is stopped, the dysregulated neurochemistry returns, the dormant ideas and experiences become reinvested with aberrant salience, and a relapse occurs. the article provides a heuristic framework for linking the psychological and biological in psychosis. predictions of this hypothesis, particularly regarding the possibility of synergy between psychological and pharmacological therapies, are presented. the author describes how the hypothesis is complementary to other ideas about psychosis and also discusses its limitations. view show abstract beauty in the brain of the beholder article jun neuron carl senior facial beauty is an honest signal of the genotypic and phenotypic quality of the bearer. beautiful people are thus regarded as high-value mates who maximize reproductive success by producing viable offspring. here, the functional neuroanatomy of facial beauty is reviewed and placed into the context of the distributed model for human face perception. a proposed extension of the distributed model is provided, which takes into account the neuroanatomy of beautiful face perception. view show abstract pleasures of the brain article jul brain cognition kent c berridge how does the brain cause positive affective reactions to sensory pleasure? an answer to pleasure causation requires knowing not only which brain systems are activated by pleasant stimuli, but also which systems actually cause their positive affective properties. this paper focuses on brain causation of behavioral positive affective reactions to pleasant sensations, such as sweet tastes. its goal is to understand how brain systems generate 'liking,' the core process that underlies sensory pleasure and causes positive affective reactions. evidence suggests activity in a subcortical network involving portions of the nucleus accumbens shell, ventral pallidum, and brainstem causes 'liking' and positive affective reactions to sweet tastes. lesions of ventral pallidum also impair normal sensory pleasure. recent findings regarding this subcortical network's causation of core 'liking' reactions help clarify how the essence of a pleasure gloss gets added to mere sensation. the same subcortical 'liking' network, via connection to brain systems involved in explicit cognitive representations, may also in turn cause conscious experiences of sensory pleasure. view show abstract parsing reward article oct trends neurosci kent c berridge terry e. robinson advances in neurobiology permit neuroscientists to manipulate specific brain molecules, neurons and systems. this has lead to major advances in the neuroscience of reward. here, it is argued that further advances will require equal sophistication in parsing reward into its specific psychological components: ( ) learning (including explicit and implicit knowledge produced by associative conditioning and cognitive processes); ( ) affect or emotion (implicit 'liking' and conscious pleasure) and ( ) motivation (implicit incentive salience 'wanting' and cognitive incentive goals). the challenge is to identify how different brain circuits mediate different psychological components of reward, and how these components interact. view show abstract do pretty women inspire men to discount the future article jun proc biol sci margo wilson martin daly organisms 'discount the future' when they value imminent goods over future goods. optimal discounting varies: selection should favour allocations of effort that effectively discount the future relatively steeply in response to cues promising relatively good returns on present efforts. however, research on human discounting has hitherto focused on stable individual differences rather than situational effects. in two experiments, discounting was assessed on the basis of choices between a smaller sum of money tomorrow and a larger sum at a later date, both before and after subjects rated the 'appeal' of photographs. in experiment , men and women saw either attractive or unattractive opposite-sex faces; in experiment , participants saw more or less appealing cars. as predicted, discounting increased significantly in men who viewed attractive women, but not in men who viewed unattractive women or women who viewed men; viewing cars produced a different pattern of results. view show abstract probing reward function in post-traumatic stress disorder with beautiful facial images article jul psychiat res igor elman dan ariely nina mazar pitman roger reward dysfunction may be implicated in post-traumatic stress disorder (ptsd). this study applied a behavioral probe, known to activate brain reward regions, to subjects with ptsd. male heterosexual vietnam veterans with (n = ) or without (n = ) current ptsd were administered two tasks: (a) key pressing to change the viewing time of average or beautiful female or male facial images, and (b) rating the attractiveness of these images. there were no significant group differences in the attractiveness ratings. however, ptsd patients expended less effort to extend the viewing time of the beautiful female faces. these findings suggest a reward deficit in ptsd. view show abstract a sex difference in features that elicit genital response article nov biol psychol meredith l. chivers j. michael bailey previous research suggests that women's genital arousal is an automatic response to sexual stimuli, whereas men's genital arousal is dependent upon stimulus features specific to their sexual interests. in this study, we tested the hypothesis that a nonhuman sexual stimulus would elicit a genital response in women but not in men. eighteen heterosexual women and heterosexual men viewed seven sexual film stimuli, six human films and one nonhuman primate film, while measurements of genital and subjective sexual arousal were recorded. women showed small increases in genital arousal to the nonhuman stimulus and large increases in genital arousal to both human male and female stimuli. men did not show any genital arousal to the nonhuman stimulus and demonstrated a category-specific pattern of arousal to the human stimuli that corresponded to their stated sexual orientation. these results suggest that stimulus features necessary to evoke genital arousal are much less specific in women than in men. view show abstract a neurobehavioral model of affiliative bonding: implications for conceptualizing a human trait of affiliation article jul behav brain sci richard a. depue jeannine v. morrone-strupinsky because little is known about the human trait of affiliation, we provide a novel neurobehavioral model of affiliative bonding. discussion is organized around processes of reward and memory formation that occur during approach and consummatory phases of affiliation. appetitive and consummatory reward processes are mediated independently by the activity of the ventral tegmental area (vta) dopamine (da)-nucleus accumbens shell (nas) pathway and the central corticolimbic projections of the u-opiate system of the medial basal arcuate nucleus, respectively, although these two projection systems functionally interact across time. we next explicate the manner in which da and glutamate interact in both the vta and nas to form incentive-encoded contextual memory ensembles that are predictive of reward derived from affiliative objects. affiliative stimuli, in particular, are incorporated within contextual ensembles predictive of affiliative reward via: (a) the binding of affiliative stimuli in the rostral circuit of the medial extended amygdala and subsequent transmission to the nas shell; (b) affiliative stimulus-induced opiate potentiation of da processes in the vta and nas; and (c) permissive or facilitatory effects of gonadal steroids, oxytocin (in interaction with da), and vasopressin on (i) sensory, perceptual, and attentional processing of affiliative stimuli and (ii) formation of social memories. among these various processes, we propose that the capacity to experience affiliative reward via opiate functioning has a disproportionate weight in determining individual differences in affiliation. we delineate sources of these individual differences, and provide the first human data that support an association between opiate functioning and variation in trait affiliation. view show abstract the evolutionary psychology of facial beauty article feb annu rev psychol gillian rhodes what makes a face attractive and why do we have the preferences we do? emergence of preferences early in development and cross-cultural agreement on attractiveness challenge a long-held view that our preferences reflect arbitrary standards of beauty set by cultures. averageness, symmetry, and sexual dimorphism are good candidates for biologically based standards of beauty. a critical review and meta-analyses indicate that all three are attractive in both male and female faces and across cultures. theorists have proposed that face preferences may be adaptations for mate choice because attractive traits signal important aspects of mate quality, such as health. others have argued that they may simply be by-products of the way brains process information. although often presented as alternatives, i argue that both kinds of selection pressures may have shaped our perceptions of facial beauty. view show abstract face perception is modulated by sexual preference article feb curr biol felicitas kranz alumit ishai face perception is mediated by a distributed neural system in the human brain . the response to faces is modulated by cognitive factors such as attention, visual imagery, and emotion ; however, the effects of gender and sexual orientation are currently unknown. we used fmri to test whether subjects would respond more to their sexually preferred faces and predicted such modulation in the reward circuitry. forty heterosexual and homosexual men and women viewed photographs of male and female faces and assessed facial attractiveness. regardless of their gender and sexual orientation, all subjects similarly rated the attractiveness of both male and female faces. within multiple, bilateral face-selective regions in the visual cortex, limbic system, and prefrontal cortex, similar patterns of activation were found in all subjects in response to both male and female faces. consistent with our hypothesis, we found a significant interaction between stimulus gender and the sexual preference of the subject in the thalamus and medial orbitofrontal cortex, where heterosexual men and homosexual women responded more to female faces and heterosexual women and homosexual men responded more to male faces. our findings suggest that sexual preference modulates face-evoked activation in the reward circuitry. view show abstract compulsive drug use linked to sensitized ventral striatal dopamine transmission article may ann neurol andrew h evans nicola pavese andrew david lawrence paola piccini a small group of parkinson's disease (pd) patients compulsively use dopaminergic drugs despite causing harmful social, psychological, and physical effects and fulfil core diagnostic and statistical manual (of mental disorders) fourth edition criteria for substance dependence (dopamine dysregulation syndrome [dds]). we aimed to evaluate levodopa-induced dopamine neurotransmission in the striatum of patients with dds compared with pd control patients. we used a two-scan positron emission tomography protocol to calculate the percentage change in ( )c-raclopride binding potential from a baseline withdrawal (off drug) state to the binding potential after an oral dose of levodopa. we related the subjective effects of levodopa to the effects on endogenous dopamine release of a pharmacological challenge with levodopa in eight control pd patients and eight patients with dds. pd patients with dds exhibited enhanced levodopa-induced ventral striatal dopamine release compared with levodopa-treated patients with pd not compulsively taking dopaminergic drugs. the sensitized ventral striatal dopamine neurotransmission produced by levodopa in these individuals correlated with self-reported compulsive drug "wanting" but not "liking" and was related to heightened psychomotor activation (punding). this provides evidence that links sensitization of ventral striatal circuitry in humans to compulsive drug use. view show abstract is it possible to dissociate ‘liking’ and ‘wanting’ for foods in humans? a novel experimental procedure article feb physiol behav graham finlayson neil king john blundell berridge's model (e.g. [berridge kc. food reward: brain substrates of wanting and liking. neurosci biobehav rev ; : - .; berridge kc, robinson t e. parsing reward. trends neurosci ; : - .; berridge kc. motivation concepts in behavioral neuroscience. physiol behav ; : - ]) outlines the brain substrates thought to mediate food reward with distinct 'liking' (hedonic/affective) and 'wanting' (incentive salience/motivation) components. understanding the dual aspects of food reward could throw light on food choice, appetite control and overconsumption. the present study reports the development of a procedure to measure these processes in humans. a computer-based paradigm was used to assess 'liking' (through pleasantness ratings) and 'wanting' (through forced-choice photographic procedure) for foods that varied in fat (high or low) and taste (savoury or sweet). participants completed the program when hungry and after an ad libitum meal. findings indicate a state (hungry-satiated)-dependent, partial dissociation between 'liking' and 'wanting' for generic food categories. in the hungry state, participants 'wanted' high-fat savoury>low-fat savoury with no corresponding difference in 'liking', and 'liked' high-fat sweet>low-fat sweet but did not differ in 'wanting' for these foods. in the satiated state, participants 'liked', but did not 'want', high-fat savoury>low-fat savoury, and 'wanted' but did not 'like' low-fat sweet>high-fat sweet. more differences in 'liking' and 'wanting' were observed when hungry than when satiated. this procedure provides the first step in proof of concept that 'liking' and 'wanting' can be dissociated in humans and can be further developed for foods varying along different dimensions. other experimental procedures may also be devised to separate 'liking' and 'wanting'. view show abstract berridge kc. the debate over dopamine’s role in reward: the case for incentive salience. psychopharmacology (berl) : - article may psychopharmacology kent c berridge introduction: debate continues over the precise causal contribution made by mesolimbic dopamine systems to reward. there are three competing explanatory categories: 'liking', learning, and 'wanting'. does dopamine mostly mediate the hedonic impact of reward ('liking')? does it instead mediate learned predictions of future reward, prediction error teaching signals and stamp in associative links (learning)? or does dopamine motivate the pursuit of rewards by attributing incentive salience to reward-related stimuli ('wanting')? each hypothesis is evaluated here, and it is suggested that the incentive salience or 'wanting' hypothesis of dopamine function may be consistent with more evidence than either learning or 'liking'. in brief, recent evidence indicates that dopamine is neither necessary nor sufficient to mediate changes in hedonic 'liking' for sensory pleasures. other recent evidence indicates that dopamine is not needed for new learning, and not sufficient to directly mediate learning by causing teaching or prediction signals. by contrast, growing evidence indicates that dopamine does contribute causally to incentive salience. dopamine appears necessary for normal 'wanting', and dopamine activation can be sufficient to enhance cue-triggered incentive salience. drugs of abuse that promote dopamine signals short circuit and sensitize dynamic mesolimbic mechanisms that evolved to attribute incentive salience to rewards. such drugs interact with incentive salience integrations of pavlovian associative information with physiological state signals. that interaction sets the stage to cause compulsive 'wanting' in addiction, but also provides opportunities for experiments to disentangle 'wanting', 'liking', and learning hypotheses. results from studies that exploited those opportunities are described here. conclusion: in short, dopamine's contribution appears to be chiefly to cause 'wanting' for hedonic rewards, more than 'liking' or learning for those rewards. view show abstract ventral striatal control of appetitive motivation: role in ingestive behavior and reward-related learning article feb neurosci biobehav r ann e kelley the nucleus accumbens is a brain region that participates in the control of behaviors related to natural reinforcers, such as ingestion, sexual behavior, incentive and instrumental learning, and that also plays a role in addictive processes. this paper comprises a review of work from our laboratory that focuses on two main research areas: (i). the role of the nucleus accumbens in food motivation, and (ii). its putative functions in cellular plasticity underlying appetitive learning. first, work within a number of different behavioral paradigms has shown that accumbens neurochemical systems play specific and dissociable roles in different aspects of food seeking and food intake, and part of this function depends on integration with the lateral hypothalamus and amygdala. we propose that the nucleus accumbens integrates information related to cognitive, sensory, and emotional processing with hypothalamic mechanisms mediating energy balance. this system as a whole enables complex hierarchical control of adaptive ingestive behavior. regarding the second research area, our studies examining acquisition of lever-pressing for food in rats have shown that activation of glutamate n-methyl-d-aspartate (nmda) receptors, within broadly distributed but interconnected regions (nucleus accumbens core, posterior striatum, prefrontal cortex, basolateral and central amygdala), is critical for such learning to occur. this receptor stimulation triggers intracellular cascades that involve protein phosphorylation and new protein synthesis. it is hypothesized that activity in this distributed network (including d receptor activity) computes coincident events and thus enhances the probability that temporally related actions and events (e.g. lever pressing and delivery of reward) become associated. such basic mechanisms of plasticity within this reinforcement learning network also appear to be profoundly affected in addiction. view show abstract love relations: normality and pathology jan o kernberg kernberg, o. ( ). love relations: normality and pathology. new haven, ct: yale university press. beauty in a smile: the role of medial orbitofrontal cortex in facial attractiveness jan - o ' doherty j winston j critchley h perrett d burt d m dolan o'doherty, j., winston, j., critchley, h., perrett, d., burt, d. m., & dolan, r. j. ( ). beauty in a smile: the role of medial orbitofrontal cortex in facial attractiveness. neuropsychologia, , – . jan s e taylor l c klein b p lewis t l gruenewald r a gurung updegraff taylor, s. e., klein, l. c., lewis, b. p., gruenewald, t. l., gurung, r. a., & updegraff, j. a. ( ). recommended publications discover more article multidimensional evaluation of monetary incentive strategies for weight control april · the psychological record brian e. mavis bertram e. stöffelmayr this study compares the effectiveness of five monetary incentive strategies in the context of a behavioral weight management program. four weight-contingent strategies were used: (a) continuous positive reinforcement; (b) monetary response cost; (c) positive reinforcement with a lottery system; and (d) response cost with a lottery system. for comparison, a fifth group was based on an ... [show full abstract] attendance-contingent monetary reward condition. subjects were randomly assigned to one of five groups and participated in a -session/ -week behavioral weight loss program. twelve behavioral and attitudinal criteria were used to compare the programs, related to weight loss, self-efficacy, program acceptance, dropout, and maintenance activities. differences among the monetary contingencies were found for weekly weight goal attainment, dropout rate, participation in subsequent maintenance activities, perceived program reactance, group satisfaction, and satisfaction with the incentive strategy. the results demonstrate the broad effects beyond the contractually specified contingencies, which can influence participant performance, and support the use of monetary reward incentive procedures. read more article full-text available dopamine and addiction: a couple between the reason and irrationality december · biofutur serge h ahmed view full-text article components of the behavioral activation system and functional impulsivity: a test of discriminant hy... december · journal of research in personality luigi leone paolo maria russo it has recently been suggested that the concept of functional impulsivity bears some similarity to the sensitivity of the behavioral activation system (bas; smillie & jackson, ). in the present research we take a closer look at this idea, testing more specific hypotheses on the associations of different bas-related components with functional and dysfunctional impulsivity. analyzing a sample ... [show full abstract] of , we found that the drive component was uniquely connected with functional impulsivity, and fun seeking was linked to both impulsivities, but more weakly so to functional impulsivity compared with drive. reward responsiveness was unrelated to impulsivity. implications for the conceptualization of functional impulsivity and for a complex view of bas-related functions are addressed. read more article the specific role of dopamine in the striatum during operant learning december · neuroscience and behavioral physiology natalia ivlieva d. a. ivliev the role of dopamine in behavior is in a state of permanent controversy. the notion of ‘prediction error’ is a central component in current reward-based models of learning, but there are many caveats and contradictions in the supporting data. in this paper we propose that the same dopamine signal can both promote an action and reinforce it and we outline a novel model of reward-based learning in ... [show full abstract] which dopamine operates as a teaching signal with da release starting well before and persisting beyond the action being reinforced. the post-response signal providing the true excitatory drive for long-term potentiation (ltp) comes from the intralaminar nuclei of the thalamus. the main component of this hypothetical mechanism is the direct striatal projection neuron pathway, while there are indications that the indirect pathway is fundamentally able to modulate the direct pathway, thus providing behavioral flexibility. read more last updated: dec looking for the full-text? you can request the full-text of this article directly from the authors on researchgate. request full-text already a member? log in researchgate ios app get it from the app store now. install keep up with your stats and more access scientific knowledge from anywhere or discover by subject area recruit researchers join for free loginemail tip: most researchers use their institutional email address as their researchgate login passwordforgot password? keep me logged in log in or continue with linkedin continue with google welcome back! please log in. email · hinttip: most researchers use their institutional email address as their researchgate login passwordforgot password? keep me logged in log in or continue with linkedin continue with google no account? sign up company about us news careers support help center business solutions advertising recruiting © - researchgate gmbh. all rights reserved. terms privacy copyright imprint vegf-b: a thing of beauty research highlight cell research ( ) : - . © ibcb, sibs, cas all rights reserved - / $ . www.nature.com/cr npg correspondence: xuri li e-mail: lixur@nei.nih.gov vegf-b: a thing of beauty xuri li national institutes of health/national eye institute, rockville, , maryland, usa cell research ( ) : - . doi: . /cr. . ; published online june more than a decade ago, when we first embarked on our journey to delin- eate the biological function of vascular endothelial growth factor b (vegf-b), we had a hard time comprehending why vegf-b was needed. in mice, genetic deletion of vegf-b seemed to be harm- less, since the vegf-b null mice, to a large extent, can still live a fairly normal life [ ]. moreover, overexpression of vegf-b in different mouse tissues, such as the skin or skeletal muscle, did not seem to result in any obvious pheno- type [ ]. due to these seemingly come- to-nothing findings, many researchers lost their scientific interests in vegf-b. however, new discoveries on vegf-b function have recently begun to surprise us – the latest one being that vegf-b plays an important role in modulating fat utilization. deeper scrutiny dem- onstrated that vegf-b deficient mice display greater amount of body fat and weight due to impaired fatty acid (fa) uptake by the endothelium, as shown elegantly in a recent study from dr ulf eriksson’s laboratory [ ]. vegf-b was discovered in as a vegf homologue [ ]. vegf-b is produced as a secreted homodimer. due to alternative splicing, the vegf-b gene gives rise to two isoforms, vegf-b and vegf-b , which are homodimers of about and kda, respectively. vegf-b can be proteolytically pro- cessed at arg and give rise to a kda dimer. vegf-b has a heparin- binding domain, so that upon secre- tion, vegf-b binds to cell-surface heparan sulphate proteoglycans. by contrast, vegf-b does not contain the heparin-binding domain and there- fore is more soluble. vegf-b binds to vascular endothelial growth factor receptor- (vegfr- ) and neuropilin- (nrp- ) [ , ]. vegf-b is expressed early during fetal development in mice, and remains abundantly expressed in most tissues and organs in adult mice, especially in the cardiac myocytes, skeletal muscles and neuronal tissues [ ]. vegf-b is the predominant isoform expressed in most tissues and organs, accounting for more than % of the total vegf-b transcripts, while vegf-b is expressed at lower levels and in a limited number of tissues [ ]. for many years, research efforts on vegf-b have focused on its speculated angiogenic activities, based on its high sequence homology and similar receptor binding pattern to vegf, a prototype angiogenic factor. however, studies along this line, most of the time, led to inconsistent results [ ]. compared with the other vegf family members, vegf-b has received much less atten- tion thus far. recent years have witnessed several advances in vegf-b biology. first, dif- ferent groups have shown that vegf-b is a potent neuroprotective factor [ - ]. second, it is recently recognized that vegf-b has an ischemic myocardium- specific angiogenic activity while being minimally angiogenic in most of the other organs [ , , ]. compared with these findings, the more recent discovery by dr eriksson’ group, per- haps is more unexpected and striking. in this study, hagberg et al. [ ] showed that vegf-b is a critical regulator of energy metabolism by regulating fatty acid uptake. in their recent study, hagberg et al. [ ] provided several lines of evidence at different levels to show that vegf-b has a unique and critical role in regu- lating fatty acid transportation. first, the authors conducted bioinformatic analysis of published microarray data and found that vegf-b expression was closely associated with the expression of nuclear-encoded mitochondrial genes under different conditions in mice. this association appears to be specific to vegf-b, since the other vegf family members, such as vegf and plgf, do not display the same type of association in their expression. these observations at gene expression level thus pointed to a potential role of vegf-b in energy metabolism. the authors then went on and verified the significance of the above observations using cultured cells, and found that, in endothelial cells, vegf-b stimulation upregulated the expression of the fatty acid transport proteins (fatps), which are a family of proteins needed for fatty acid transpor- tation across the endothelium. indeed, in a two-liquid-compartment endothelial cell culture assay, vegf-b treatment increased trans-endothelial transfer of c-labelled oleic acid from the up- per to the basal liquid compartment, cell research | vol no | july npg figure a unique role of vegf-b in fatty acid (fa) uptake (a) vegf-b expression is tightly correlated with the expression of nuclear-encoded mitochondrial genes, indicating a role of vegf-b in energy metabolism. in normal mice, tissues with high energy metabolism demand, such as skeletal muscles, cardiac myocytes and brown adipose tissues (bats), express high levels of vegf-b. upon binding to vegfr- and nrp- expressed by the vascular endothelial cells, vegf-b upregulates the expression of fatty acid transport proteins (fatps). the fatps transport the fatty acids from blood stream across the en- dothelium to peripheral tissues for energy production. (b) in the vegf-b deficient mice, lack of vegf-b results in decreased fatp expression, and subsequently reduces fa uptake by the endothelium. this in turn leads to decreased fa consumption by the heart, muscle and brown adipose tissue. importantly, as a result of the impaired fa transport and utilization, the uncon- sumed fa are accumulated in the white adipose tissues (wats), resulting in greater body fat mass and weight in the vegf-b null mice. the biological consequences of the impaired fa uptake in the vegf-b deficient hearts, muscles and bats remain unclear. it is also unknown whether the reported survival/antiapoptotic effect of vegf-b is linked to its fa-transport function. in addition, it remains to be studied why vegf-b deficiency does not blunt fa uptake in the wats, while this is true in other tissues. fa transportation metabolic demand brown adipose tissue (bat) wild-type mice white adipose tissue (wat) fa transportation apoptosis brown adipose tissue (bat) white adipose tissue (wat) vegf-b deficient mice vefg-b vegfr- nrp- fatp fatty acid mitochondria endothelial cell cardiomyocyte skeletal muscle cell brown adipocyte white adipocyte a b transport stop stop stop go demonstrating that vegf-b promotes fa transport across the endothelium by upregulating the expression of the fatps. in vivo, hagberg et al. found that vegf-b deficient mice had a reduced fa uptake, leading to significantly less fa accumulation in their hearts, muscles and brown adipose tissues (bats). in- stead, due to the impaired fa transport and utilization, the unconsumed fa were shunted to white adipose tissues (wats) www.cell-research.com | cell research npg and resulted in increased amount of body fat and weight in the vegf-b null mice (figure ). furthermore, as a compensation for the reduced lipid utilization, the vegf-b deficient mice had an increased glucose uptake and utilization in their hearts as an alterna- tive source of energy. mechanistically, the authors revealed that the effect of vegf-b on endothelial fa uptake was mediated by flt- and nrp- . this no- tion is supported by the findings that in mice lacking functional flt- and nrp , the cardiac expression of fatps was de- creased. indeed, the authors also found that the nrp deficient mice displayed a similar defect in fatty acid uptake to peripheral tissues. one common exciting aspect of all breakthroughs is that they always lead to interesting questions. there appears to be an apparent tissue specificity of vegf-b action in affecting fatty acid metabolism, since vegf-b deficient mice display an impaired fa uptake in their bats, but an increased fa uptake in their wats. why does vegf-b deficiency not blunt fa uptake in the wats, since vegf-b is a secreted protein and can be found in the blood stream in differ- ent tissues? are flt- and nrp- not expressed by the endothelium in wat? or, does fa uptake in wats utilize dif- ferent molecules other than vegf-b? furthermore, it is known that flt- and nrp- are expressed by many cell types. does vegf-b affect fa uptake in other types of cells apart from vascular endothelial cells? it would be interesting to know the direct or indirect biological conse- quences of the impaired fa uptake in the vegf-b deficient heart, muscle and bat. vegf-b has been shown to be a potent survival factor [ , ]. vegf-b treatment increased the survival of different cell types, including neurons [ , ], blood vessels [ ], and cardiac myocytes [ , ]. it would be interest- ing to see whether the survival effect of vegf-b is linked to its fa-transport function, or, whether they are two sepa- rate pathways. it is noteworthy that do- cosahexaenoic acid (dha), one major n- fatty acid, is specifically required for retinal neuronal survival [ ]. this has indicated a link between fa uptake and neuronal survival, in both of which vegf-b plays an important role. also, it remains unclear why vegf- b , the more diffusible form of vegf- b, was more effective than the heparin- binding form of vegf-b, vegf-b , in inducing fatp expression. in the study by hagberg et al., the co-expression of vegf-b with the mitochondrial protein genes was the initial indication of a role of vegf-b in energy metabolism. however, vegf-b is secreted and soluble and can be transported freely to different tissues through the blood stream. instead, one would hypothesize that vegf-b , which is heparin bind- ing and less soluble with a greater tis- sue specificity, might be more likely to fulfill the tissue-specific demand of fa uptake to match up with the oxidative capacity of that specific tissue. it is particularly interesting to note that vegf-b deficiency results in greater body fat mass and weight in mice. given that obesity is becoming an epidemic in developed and developing countries and causes significant morbid- ity and mortality, it will be interesting to further delve into the expression and functional status of vegf-b in obese patients, and to verify whether obesity in human may potentially be associated with any functional defect of vegf-b, and if so, whether fortified vegf-b expression could help fight against obesity. moreover, it is known that fatty acid uptake affects numerous biological processes in the body, including car- diovascular, neurological and immune functions. it is therefore reasonable to expect that the discovery of a new critical player in lipid uptake, such as vegf-b, might open up new therapeu- tic possibilities to tackle pathological lipid accumulation in obesity, diabetes, cardiovascular and other diseases. we await the next surprise from vegf-b. acknowledgments the author thanks dr fan zhang (na- tional institutes of health/national eye institute) for the artistic work for the fig- ure, and thanks dr lijin dong (national institutes of health/national eye institute) and the laboratory members for the helpful comments. references aase k, von euler g, li x, et al. vas- cular endothelial growth factor-b-defi- cient mice display an atrial conduction defect. circulation ; : - . li x, tjwa m, van hove i, et al. re- evaluation of the role of vegf-b sug- gests a restricted role in the revascular- ization of the ischemic myocardium. arterioscler thromb vasc biol ; : - . hagberg ce, falkevall a, wang x, et al. vascular endothelial growth factor b controls endothelial fatty acid up- take. nature ; : - . olofsson b, pajusola k, kaipainen a, et al. vascular endothelial growth factor b, a novel growth factor for en- dothelial cells. proc natl acad sci usa ; : - . olofsson b, korpelainen e, pepper ms, et al. vascular endothelial growth factor b (vegf-b) binds to vegf receptor- and regulates plasminogen activator activity in endothelial cells. proc natl acad sci usa ; : - . makinen t, olofsson b, karpanen t, et al. differential binding of vascular endothelial growth factor b splice and proteolytic isoforms to neuropilin- . j biol chem ; : - . li x, aase k, li h, von euler g, eriks- son u. isoform-specific expression of vegf-b in normal tissues and tumors. growth factors ; : - . li x, lee c, tang z, et al. vegf-b: a survival, or an angiogenic factor? cell adh migr ; : - . li y, zhang f, nagai n, et al. vegf-b inhibits apoptosis via vegfr- -medi- ated suppression of the expression of bh -only protein genes in mice and rats. j clin invest ; : - . poesen k, lambrechts d, van damme cell research | vol no | july npg p, et al. novel role for vascular en- dothelial growth factor (vegf) recep- tor- and its ligand vegf-b in motor neuron degeneration. j neurosci ; : - . zhang f, tang z, hou x, et al. vegf-b is dispensable for blood vessel growth but critical for their survival, and vegf-b targeting inhibits pathologi- cal angiogenesis. proc natl acad sci usa ; : - . lahteenvuo je, lahteenvuo mt, kive- la a, et al. vascular endothelial growth factor-b induces myocardium-specific angiogenesis and arteriogenesis via vascular endothelial growth factor receptor- - and neuropilin receptor- - -dependent mechanisms. circulation ; : - . karpanen t, bry m, ollila hm, et al. overexpression of vascular endothelial growth factor-b in mouse heart alters cardiac lipid metabolism and induces myocardial hypertrophy. circ res ; : - . tirziu d, chorianopoulos e, moodie kl, et al. myocardial hypertrophy in the absence of external stimuli is in- duced by angiogenesis in mice. j clin invest ; : - . rotstein np, aveldano mi, barrantes fj, politi le. docosahexaenoic acid is required for the survival of rat retinal photoreceptors in vitro. j neurochem ; : - . vegf-b: a thing of beauty acknowledgements references omni-beauty as a divine attribute jon robson department of philosophy, university of nottingham, nottingham, ng rd, uk. jonvrobson@gmail.com abstract: the claim that god is perfectly beautiful has played a key role within the history of a number of religious traditions. however, this view has received surprisingly little attention from philosophers of religion in recent decades. in this paper i aim to remedy this neglect by addressing some key philosophical issues surrounding the doctrine of divine beauty. i begin by considering how best to explicate the claim the god is perfectly beautiful before moving on to ask what consequences accepting this claim will have for our broader theorising in philosophy. the beauty of god apparent attributions of beauty to god abound in various theistic traditions. to focus – as i will in this paper – only on the christian religion, we seem to find god’s beauty praised at length by a variety of sources. scripture describes god as ‘the king in his beauty’ (isaiah : ) and the psalmist expresses the desire to ‘behold the beauty of the lord’. likewise, the tradition is replete with what appear to be descriptions of god’s beauty. augustine describes him as ‘the most beautiful of all beings’ (augustine : ), aquinas proclaims that he ‘is goodness and beauty itself’ ( / : ), and jonathan edwards praises ‘the infinite mailto:jonvrobson@gmail.com beauty and excellency of his nature’ ( : ). similarly, god’s beauty is frequently exalted in a plethora of hymns, songs, and liturgies. it is notable, however, that there has been very little effort in contemporary philosophy of religion to proffer a precise analysis of such claims. what are we to make of this? one possible explanation is that philosophers of religion have been inclined to dismiss such language as mere puffery. perhaps the faithful, keen to praise god in the most exuberant terms available, have merely heaped every available positive appellation upon him without any real consideration as to whether such epithets are really applicable to a divine being. such an explanation would, perhaps, account for some of the claims made in folk religious discourse and popular worship songs, but it hardly explains the careful and in-depth discussions of god’s beauty found in the writings of various philosophers and theologians within the tradition. it seems, then, that there is (at least prima facie) good reason to treat these claims as a genuine part of christian doctrine, something which makes their recent neglect even more puzzling. my primary aim in this paper will be to begin to remedy this neglect. once we have accepted talk of god’s beauty as a genuine part of the tradition, this raises the further question of how best to account for such talk. one suggestion is that it is, in some respect, metaphorical. ascriptions of god’s beauty, on this view, are no more to be taken literally than descriptions of his outstretched arm or the shelter of his wings. alternatively, we might accept that the christian tradition literally numbers beauty amongst the divine attributes but argue that the tradition errs in this respect. for the purposes of this paper, i will have very little to say about the plausibility, or otherwise, of these approaches. rather, i will assume that we should take talk of god’s beauty at face value – both in terms of its content and its truth – and ask what implications this will have. i begin by considering how best to analyse the relevant attribute of divine beauty (which i term ‘omni-beauty’). i then survey some implications which attributing omni-beauty to god has for some important debates within aesthetics. finally, i consider the relationship between omni-beauty and other divine attributes. defining omni-beauty it is clear from the examples above that there is a prominent tradition which is, if taken at face value, committed to the claim that beauty is a divine attribute. yet, it might reasonably be queried what precisely is meant by ‘beauty’ here given the numerous competing accounts of the nature of beauty. i will not, however, commit to any particular analysis of beauty here for three reasons. first, defending any account of beauty in general would require a lengthy diversion from the main topic of the paper. second, offering such an account strikes me as unnecessary for my, rather modest, purposes here. while a complete account of god’s beauty would, most likely, require a detailed understanding of beauty in general, such an understanding is not required for a mere preliminary foray into reinvigorating this topic. (consider, by way of comparison, how rarely discussions of omniscience come packaged with complete analyses of the necessary and sufficient conditions for knowledge.) finally, committing to any one account would require my taking sides regarding various issues on which i intend to remain neutral for the purposes of this paper. these issues concern, for example, whether there can be beauties which aren’t perceptible by means of the senses and the extent to which judgements of beauty are objective. i will argue below that accepting certain claims about god’s beauty commits us to particular views on such issues but will take no stance as to whether this is a reason to accept the latter or to reject the former. rather than offering a detailed definition of beauty, then, i will instead merely start from an ordinary ‘folk’ understanding of the concept (again, paralleling many discussions of other divine attributes). of course, it may well turn out that, as i will discuss at length below, such a quotidian understanding of beauty is inadequate when it comes to understanding the nature of divine beauty. regardless, though, it will still provide us with a useful starting point. whatever stance we take concerning beauty in general, though, it is clear that those throughout the christian tradition who have praised the beauty of god are not merely suggesting that god is one beautiful object amongst many. as with his other perfections, it would not do for god to be surpassed (or equalled) in terms of beauty by any other being. further, it seems that we should maintain – in keeping with the tradition of perfect being theology – that god’s beauty exceeds not only that of any other actual being but of any other possible being. an obvious initial suggestion, then, might be that a being is omni-beautiful iff it is more beautiful than any other possible being (or collection of such beings). this rough account of omni-beauty is, however, rather uninformative. as with other divine attributes – omnipotence, omniscience, and so forth – merely asserting that god possesses the highest possible degree of some perfection hardly serves as an analysis of the relevant property. further, there are (as i will discuss further below) reasons to doubt whether this account really captures the relevant notion of god’s all-surpassing beauty found in the tradition. maximal beauty dealing first with the issue of how best to flesh out this account, it is important to observe that some initially appealing attempts to further analyse god’s role as the most beautiful of all possible beings quickly prove untenable. it cannot, for example, be that god is omni-beautiful in virtue of straightforwardly instantiating all possible beauties. there are, first, certain ways of being beautiful – such as the beauty instantiated by the vibrant mix of colours within a painting – which it seems can only be possessed by physical objects and which, as such, could not be instantiated by a transcendent immaterial deity. just as geach ( : ) argues that, perfect goodness notwithstanding, there are certain putative virtues (such as chastity and temperance) which god – owing to his immaterial nature – could not possess. second, instantiating certain kinds of beauty is incompatible with instantiating others. some objects are beautiful in virtue of their complexity, others in virtue of their simplicity. likewise, some objects are beautiful because of their serenity and others because of their frantic energy. clearly, though, no one object can possess all of these varied beauties. or, rather, no object considered as a whole can possess them in any straightforward sense. it is, of course, possible for a single object to have parts which instantiate each of these features. however (even setting aside concerns relating to divine simplicity) it is clear that this qualification won’t dispense with the underlying problem here. there are certain ways in which an object as a whole can be beautiful which depend on the inter-relations between all of its different parts and, again, some of these ways of being beautiful are incompatible with others. consider, for example, the contrast between an object that it is beautiful because of the harmonious homogeneity of its parts and one that is beautiful because of the wonderfully unexpected contrasts between its various parts. finally, there are certain kinds of putative beauty that appear to be unworthy of a perfect being. we often talk, for example, of finding beauty in an object because of its fragility or ephemerality. such beauty would, however, clearly be incompatible with god’s omnipotence and eternity. again, we can draw comparisons with geach’s ( ) discussion of the virtues and his claim that god cannot, qua omnipotent being, exhibit virtues such as courage (since nothing could ever pose even an apparent threat to him) or prudence (since there are no limits to the resources available to him). it seems, then, that attempts to flesh out omni-beauty in terms of the straightforward possession of all possible beauties fail. can we do better? one possibility is to maintain that god’s omni-beauty consists in his uniquely instantiating the greatest compossible set of beauties. that is, that he alone instantiates a set of beauties which – in terms of either the range of beauties instantiated, the extent of their beautifulness, or both – exceeds the beauty of any other possible set. of course, much more would need to be said concerning how to spell out the details of this account. what, for example, is the nature of this set of beauties? why should we believe that there is only one such set? and why is it that god alone is able to instantiate it? there is, however, a deeper worry for accounts of this kind. to understand this worry, it will be useful to return to the relationship between omni- beauty and perfect being theology. as noted above, it cannot be the case that any being – whether actual or merely possible – is god’s peer in terms of beauty. even this doesn’t go far enough though. while it is not, strictly speaking, incompatible with the letter of perfect being theology to allow that some other being comes a close second to god in terms of any of his perfections, it is surely incompatible with the spirit of this doctrine. the idea, for example, that any created being has a level of power which provides a close rival to god’s (such that god would have to struggle to overcome it) belongs more to a manichean worldview than an orthodoxly christian one. similarly, to allow that any other being is god’s rival, even an ultimately unsuccessful rival, in terms of beauty would be anathema to most within the perfect being tradition. as such, merely appealing to god’s uniquely possessing the greatest compossible set of beauties isn’t going to do the work required from an account of omni- beauty. an obvious response at this stage would be to maintain that, for whatever reason, the relevant set of beauties which god instantiates is significantly greater than the next greatest compossible set. again, we would be faced with a number of questions concerning the exact details of how this should be spelled out but, even if we were able to answer these, this position still doesn’t seem to capture everything which those who praise god’s beauty would wish to say. first, the view as stated seems entirely consistent with treating the kinds of beauty which do not fall within the relevant set as being completely absent from god’s purview. a view which, for reasons i will discuss further below, many in the tradition would hold to be completely unacceptable. second, many theists will be inclined to maintain, paralleling moves already made with respect to other divine attributes, that it would be preferable to explain the differences between the beauty of god and the beauty of created things in terms which aren’t merely quantitative. one common motivation for this is the thought that it somehow denigrates god not to allow that there is some difference in kind, and not merely in degree, between the perfections he possesses and the corresponding attributes possessed by his creations. so, how might the proponent of the omni-beauty view address these concerns? god as source of beauty one possibility for answering this challenge is to maintain that god is not merely the unique possessor of (by far) the greatest compossible set of beauties but also, in some sense, the source of all beauties other than his own. indeed, as i will explore further below, there is already an influential view within the tradition according to which god is, to use pseudo-dionysius’s ( : ) phrase, ‘the superabundant […] source of the beauty of every beautiful thing’. how should we explicate this claim though? if the suggestion is merely that god created and sustains every beautiful thing (besides himself) then this is certainly a view which many orthodox theists will be inclined to accept. after all, god is typically taken – with some occasional exceptions i will discuss in later sections – to bear these relations to all other objects. yet, this merely causal story doesn’t seem to capture what the omni-beauty account requires. first, the causal story doesn’t capture any special relation which god bears to beauty, or to beautiful things, rather than to created things more generally. second, there is no general reason to hold that the creator of a beautiful object needs to be its superior, or even equal, in terms of beauty (many great artists weren’t much to look at). of course, god’s superior beauty would already be guaranteed by the claim that he instantiates the greatest compossible set of beauties. the underlying worry, though, is that merely claiming that god is the creator and sustainer of all beautiful things – while no doubt important in various respects concerning his power, sovereignty, and so forth – does nothing to bolster the claim that his superiority in terms of beauty isn’t a merely quantitative one. there is, however, an alternative interpretation of the ‘source of beauty’ claim available. i noted above that it seems to be a complete non-starter to claim that god straightforwardly instantiates the full range of possible beauties. there is, however, an influential view within the tradition according to which god possess all of these beauties in a less direct manner since all other beauties are, in some sense, a reflection of (or a sharing in) god’s beauty. this idea is, again, found in pseudo-dionysius who claims that from god’s ‘beauty comes the existence of everything, each being exhibiting its own way of beauty’ ( : ). similarly, edwards ( : ) describes the beauty of created beings as ‘being a communication of the divine nature and beauty’. further, the reflection view also appears well-equipped to deal with the worries introduced above. postulating that all other beauties are somehow a reflection of god’s beauty allows us to introduce a difference between the beauty of god and the beauty of created things which is not merely quantitative. similarly, it allows us to maintain a strong link between god and those beauties which he cannot straightforwardly instantiate, since these will still be a reflection of some superior beauty which god does possess. finally, it allows us to say something to differentiate between god’s relationship to beautiful objects and his relationship to ugly (or merely non-beautiful) objects. beautiful objects reflect, or participate in, god’s beauty but ugly objects do not reflect god’s ugliness since there is no divine ugliness to be reflected. still, this is far from establishing that the theist should accept that all worldly beauty is merely a reflection of, or participation in, god’s beauty. indeed, on the face of things at least, this position seems to encounter worries precisely paralleling those which beset the claim that god literally instantiates all beauties. how, for example, could the fragile beauty of a snowflake qualify as a reflection of the beauty of an a se and eternal being? or how could two incompatible kinds of beauty both be participations in the beauty of a single object? (i do not mean to suggest here that no answer could be given to such questions but merely that more work needs to be done to develop a fully satisfactory participation account of god’s beauty.) of course, any problem which does arise here will likely not be one which is peculiar to omni-beauty. it is commonplace for theists to maintain that, as aquinas ( / : ) puts it, ‘[a]ll created perfections are in god’ but also to recognise that there are various reasons why this cannot be so in a straightforward or literal sense. for example, there are, as aquinas himself (ibid.) discusses, worries that certain kinds of creaturely perfection are unworthy of god, that some physical perfections could not be instantiated by an immaterial god and that certain kinds of perfection are not capable of being co-instantiated (worries which closely parallel those concerning different kinds of creaturely beauty discussed above). famously, aquinas’ own solution to this difficulty it to propose that the various perfections of created things exist ‘in a more eminent degree’ (ibid.) in god than in created beings. so, on the thomist view, all beauties (as with all other perfections) are, in some sense, present in god but not in the same manner in which they are present in ordinary objects. rather, the beauty of these ordinary objects is a reflection of some distinct kind of beauty which god exhibits in a pre-eminent manner. influential though such a view of god’s perfections is, it is also rather opaque, and it is difficult to see precisely (or even approximately) what this kind of reflection amounts to. to some extent this difficulty is to be expected since it is also a key part of this influential thomist view that we cannot fully understand the way in which god exhibits such perfections pre-eminently. there have, however, been some attempts to elucidate this claim. timothy chappell ( : ), for example, asks us to imagine what it would be life if there were a race of aliens vastly superior to humans in intelligence and goodness, we would of course struggle to understand those aliens. but we would not, i think, struggle with the idea that our terms ‘intelligent’ and ‘good’ might be pre-eminently applicable to those aliens—more applicable to them than to anything that we had invented the terms to apply to. nor would we struggle with the idea that these hyper-intelligent and ultra-virtuous aliens might themselves propose to us that we extend or revise our use of such terms in ways that we, for our part, would be quite unable to make full sense of, even where we dimly grasped their point. such analogies are, in some respects, useful illustrations of the pre-eminence view but they don’t really help us with the particular difficulties at hand. for example, it is clearly not the case that the beauty of god which is reflected in the snowflake holds its pre-eminence by virtue of being vastly more fragile or more delicate than the snowflake. similarly, we could not extend this thought experiment to imagine, even dimly, an object which was (considered as a whole) aesthetically superior to any earthly object in terms of both its serenity and its frantic energy. again, i do not mean to suggest that such difficulties are insurmountable – some sympathetic presentations of thomist aesthetics can be found in, e.g., maurice ( ), jordan ( ) and sevier ( ) – but merely that the position it presents us with is a subtle and complex one which does not enable us to provide an easy explication of omni-beauty (or any other divine attribute). the state of play we are left, then, in a rather difficult position when it comes to efforts to explicate the nature of god’s perfect beauty. accounts which define omni-beauty merely in terms of god’s possessing the maximal possible level of beauty seem – even bracketing difficulties concerning how best to spell out such a view – to be inadequate to the task. on the other hand, accounts of omni-beauty in terms of notions such as reflection or participation appear to quickly commit us to views which are rather opaque and which are, at the very least, in need of a great deal of careful explication before they can provide us with a fully adequate account of the nature of divine beauty. there is, of course, much more which could be said here concerning these different attempts to define omni-beauty (and merely surveying extant attempts to outline and defend the reflection view concerning god’s perfections would be a monumental task). further, even once these metaphysical questions concerning the nature of god’s beauty are settled, other pressing issues are likely to arise. we would need to consider, for example, the ways in which we might come to experience or apprehend the nature of god as well as the ways in which the aesthetic character of god relates to various aspects of religious praxis. my intention here is not, however, to arrive at any definitive account of the nature of omni-beauty but merely to demonstrate that – as with the other divine perfections – the nature of god’s perfect beauty is not as easy to explicate as it may initially appear. as such, there is good reason for those philosophers who regard omni-beauty as a genuine divine attribute to dedicate renewed efforts to better understanding it. provided, of course, that we take there to be something philosophically significant about achieving such understanding. after all, if we were to hold that omni-beauty is a genuine divine attribute but that it has no important consequences for any matters of philosophical significance, then this would seem to justify its relative neglect by contemporary philosophers of religion. so, why think that omni-beauty is theoretically significant? there will, of course, be those who judge (correctly in my view) that a greater understanding of omni-beauty will be philosophically rewarding for its own sake. for those inclined to question this, though, i will argue below that accepting the omni-beauty view has important implications for a range of other philosophical issues. naturally, determining precisely what significance the omni-beauty view has would necessitate developing a precise account of the omni-beauty doctrine itself. we can, however, get some way towards exploring these consequences even without such an account. in what follows i will focus on surveying the consequences of two key (if rather underspecified) aspects of omni-beauty. first, that god is maximally beautiful by virtue of possessing (by far) the greatest compossible set of beauties. second, that god is in some sense (perhaps only causally) the source of all other beauties. in the remainder of this paper i will argue that even these rather minimal claims have important philosophical implications for, inter alia, debates within aesthetics and the philosophy of religion. realism and anti-realism one immediate suggestion is that attributions of beauty to god straightforwardly entail aesthetic realism and, therefore, the rejection of various non-realist views in aesthetics such as error theory and expressivism. if god really is beautiful, indeed omni-beautiful, then clearly there must really be such a property as beauty and, as such, we are committed to a realist meta- aesthetics. this argument would, however, be rather too quick. taking error theory first, it is certainly the case that accepting the claim that god is omni-beautiful would commit us to rejecting error theory with respect to one kind of aesthetic property; beauty. whether this would commit us to rejecting aesthetic error theory across the board is, however, a more complex matter. someone who maintains that beauty is a genuine property but that all other putative aesthetic properties – ugliness, gaudiness, gracefulness etc. – are not would not be saying anything flatly inconsistent, but their position would certainly be a difficult one to motivate. as such, i will assume that such an account is not a live option. there does not, however, seem to be any reason why someone who accepts omni-beauty as a genuine aesthetic property couldn’t adopt an error theory with respect to some traditional aesthetic properties, just as many contemporary moral realists may incline towards an error theory with respect to some putative thick moral properties such as chastity. the implications for non-cognitivism are even less clear. certainly, the kinds of claim which orthodox theists want to make regarding the beauty of god are incompatible with a crude emotivism concerning aesthetic judgements. the claim that god is omni-beautiful is clearly not treated within the tradition as merely a straightforward expression of approval but, rather, as revealing some important feature of god himself. yet, when it comes to more sophisticated forms of non-cognitivism – such as those defended by simon blackburn ( ) and alan gibbard ( ) – things are much less clear. expressivists in various domains (such as dreier ( ) and blackburn ( : - )) have argued at length that they can allow that certain claims made within these domains are true, that they are objective and mind- independent, that they relate to genuine properties of their objects, and much more besides. of course the success (or otherwise) of this expressivist project – in aesthetics and elsewhere – is very much open to dispute. whatever view we ultimately adopt with respect to this project, though, its failure certainly isn’t an immediate consequence of the claim that god is omni-beautiful. an expressivist analysis of omni-beauty would, it seems, stand or fall for reasons exactly paralleling those offered for and against aesthetic expressivism more generally. as such, while accepting the claim that god is omni-beautiful may narrow our range of meta-aesthetic options a little, it doesn’t commit us to accepting aesthetic realism. the scope of the aesthetic there have been numerous debates within aesthetics concerning precisely which objects are capable of genuinely instantiating aesthetic properties. at one extreme there are views according to which aesthetic properties, and the objects which bear them, must be straightforwardly perceptible by means of our everyday senses. this is not to deny that in certain cases perceiving such properties may require special discernment, knowledge and so forth (just as in more quotidian cases it may, to use susanna siegel’s ( ) famous example, require some training before we are able to perceptual represent the difference between pine trees and trees of other kinds). monroe beardsley ( : ), for example, maintains that ‘[t]he aesthetic object is a perceptual object’ (that is, an ‘object some of whose qualities, at least, are open to direct sensory awareness’ (ibid. )). opposed to such views are those who allow that some objects which are not straightforwardly perceptible – people’s characters (novitz ), abstracta such as mathematical theories (breitenbach ), and even philosophical arguments (warner ) – are capable of instantiating aesthetic properties. accepting god’s omni-beauty would clearly resolve these debates in a manner broadly favouring the latter camp since if god is, as classical theism would have it, a transcendent immaterial being then his beauty will not be straightforwardly perceptible by means of our ordinary senses. again, though, it is important not to overstate the case here. first, merely denying that god is perceivable by ordinary sensorial means does not entail that he is not perceivable simpliciter. indeed, a number of philosophers (most comprehensively alston ( )) have presented sustained arguments for the claim that we can have genuine perceptual experiences of god. and, once again, claims of this kind have played a prominent role within the tradition. while it is clearly theistic orthodoxy than god (along with his power, beauty, and so forth) cannot be perceived by ordinary sensory means, there is a long history – as discussed in e.g. gellman ( ) and alston ( : - ) – of positing various means by which some manner of mystical perception (or at least perception-like apprehension) of god may be achieved. further, even leaving such complications aside, the omni-beauty view does not tell us much about precisely which objects fall under the scope of the aesthetic. it is, for example, perfectly consistent for someone who accepts the view that god is omni-beautiful to deny that various other non-perceptual objects can literally be beautiful. still, accepting that god is omni-beautiful will make certain controversial aesthetic attributions considerably more palatable. allowing that god really is beautiful will entail either that non-perceptible objects can instantiate aesthetic properties or, at the very least, that such properties can be instantiated by entities which are only perceivable by means beyond mundane sensory perception. the former concession will obviously be a boon to those who claim that abstracta etc. can literally be beautiful but the latter may also render their view considerably more appealing. after all, some philosophers have (as discussed in, e.g., maddy ( )) argued for positions concerning our acquaintance with mathematical objects which appeal to some mode of quasi-perceptual access. a mode of access which looks, in certain key respects, to be analogous to the kind of religious perception proposed by alston et al. nor is this the only way in which the omni-beauty view might be of help to defenders of a wider conception of the aesthetic. the claim that certain mathematical entities are genuinely beautiful may, for example, be made more appealing if we combine the omni-beauty view with the claim that abstracta are somehow part of god’s nature. nor are such arguments restricted to the mathematical case. consider, for example, the claim that a particular individual has a beautiful character. there is – as discussed in kidd (forthcoming) and sherry ( : - ) – a strong tradition of linking claims about the beautiful characters of certain religious exemplars with the beauty of god. as such, we might find it at least prima facie plausible that we could extend some version of whatever account we give of the beauty of god to explain the beauty of the character of such religious exemplars. faultless disagreement various philosophers have recently argued that there are certain instances within aesthetics – as well as in other areas such as discussions concerning so called ‘predicates of personal taste’ – where there can be disagreements which are faultless in every sense. for disagreements of this kind to exist it would be required not only that ‘both subjects have exhausted their epistemic responsibilities towards their respective beliefs’ (baker and robson ( : )) but also that the apparently conflicting propositions which each party believes are both true (or, at a minimum, both not false). as such, someone can reason perfectly, on the basis of the evidence available to her, but still arrive at a judgement which is not faultless in this sense. those who accept this phenomenon as genuine will allow that there can be instances where, say, a truly (or, at least, not falsely) asserts ‘beethoven’s music is superior to mozart’s’ while b truly (or, at least, not falsely) asserts ‘mozart’s music is superior to beethoven’s’. how best to account for this phenomenon – and, indeed, whether the phenomenon itself is genuine – has proven extremely controversial but i will focus here on what consequences accepting the omni-beauty view has for such debates. it is clearly a consequence of the classical theistic view of god’s beauty that there cannot be such faultless disagreements regarding whether god is beautiful or regarding the relative beauties of god and any other object. anyone who believed that god was not beautiful, or that some other object was more (or as) beautiful as god, would simply be mistaken. this is not to deny that it might be possible for such beliefs to be faultless in some sense. perhaps someone could reason flawlessly from the evidence available to her to the belief that god is not beautiful, or that some other object is more beautiful than god (i take no stance on this issue here). however, the point remains that any such belief would – given our commitment to the claim that god instantiates the greatest compossible set of beauties – be false. again, though, it is important not to overstate the significance of this result. in particular, the claim that god is omni-beautiful does not entail that there is never any faultless disagreement in the stronger sense. accepting god’s omni-beauty is, for example, perfectly consistent with the disagreement concerning beethoven and mozart (outlined above) being faultless. the omni-beauty view does, however, necessitate that there are some limits to this phenomenon. this will, of course, be a welcome result for those who deny that there can ever be faultless disagreement in this sense. it need not, however, be seen as particularly bad news for advocates of the faultlessness intuition. some of those who have discussed faultless disagreement seem to presuppose that the phenomenon, if genuine, is a perfectly general one. that is, that for any aesthetic claim there will be the possibility of a case of faultless disagreement arising. yet, a more moderate view – according to which some but, not all, aesthetic judgements can be the subject of such faultless disagreements – is perfectly consistent. indeed, there are some independently compelling reasons for finding such a view attractive. for example, while there is a widespread intuition that the disagreement concerning beethoven and mozart discussed above may be faultless, it seems at least as intuitive to claim that there could be no faultless disagreement with respect to the claim that the oeuvres of both are superior to that of bananarama. as the discussion above hopefully illustrates, the claim that god is omni-beautiful has a range of wide-reaching, and underexplored, consequences for our aesthetic theorising. what’s more, there’s no reason to think that the aesthetic consequences of omni-beauty are limited to those that i have surveyed above. indeed, there are a range of other areas – such as the relationship between aesthetics and ethics, the semantics of aesthetic judgements, and the nature of the aesthetic attitude – where i believe the claim that god is omni-beautiful will have important implications. for now, though, i will turn to consider some consequences of this view which more straightforwardly fall within the purview of the philosophy of religion. in particular, i will ask what consequences the omni-beauty view has for our understanding of other divine attributes. omni-beauty and other divine attributes there is much to be learned – as shown in, e.g., stump & kretzmann ( ) and rowe ( ) – from considering the ways in which the various putative divine attributes relate to each other. omni-beauty is no exception here. i have already mentioned above that there is, on certain views of the aesthetic, a tension between god’s being immaterial and his being beautiful. i will not, however, pursue such a line of thought here and will continue to assume that we adopt a view of the aesthetic according to which objects which are not (straightforwardly) perceptual can literally be beautiful. on a more positive note, there are other divine attributes which appear to fit very well indeed with omni-beauty. consider, for example, claims concerning god’s perfect (moral) goodness. over the last century some philosophers have sought to revive traditional claims to the effect that there are fundamental links between aesthetic and moral values. wittgenstein ( / : ), for example, famously claimed that ‘ethics and aesthetics are one’ and, rather more conservatively, berys gaut ( : ) has argued that there are a number of ways in which ‘the aesthetic and the ethical are intertwined’. there are, of course, a variety of ways in which this connection could be spelled out but, regardless of such complications, the point remains that it would be very difficult for someone sympathetic to such views to endorse claims concerning god’s surpassing moral goodness without also endorsing parallel claims with respect to his beauty. indeed, someone sympathetic to the wittgensteinian view would likely take this combination to be straightforwardly incoherent. i cannot, however, hope to do justice to the full range of possible connections between omni-beauty and other divine attributes here. as such, i will focus on considering the relationship between omni-beauty and two other divine attributes; omniscience and divine sovereignty. omni-beauty and omniscience to begin to see the possible tension between omni-beauty and omniscience it will be useful to consider one of the few contemporary discussions of divine beauty by mark ian thomas robson ( ). robson argues that god’s being perfectly beautiful is incompatible with a certain kind of ersatz realism concerning possible worlds: one according to which possible worlds exist as something like ideas in the divine mind. to demonstrate this point robson asks us to consider the horrific contents of some of the possible worlds which would exist in god’s mind. for example, there would be worlds where the nazis were victorious in the second world war and go on to ‘establish a galactic empire that takes never-ending, sadistic delight in killing the innocent’ (ibid. ). he then goes on to argue that there is an inconsistency between the claim that god’s mind contains intricately detailed representations of such horrors and the view that god is perfectly beautiful. as such, robson maintains, we must – given that perfect beauty is a non-negotiable divine attribute – reject such ‘divine ersatz’ views concerning possible worlds (ibid. ). robson’s argument is, of course, controversial in several respects (as i will discuss further below) but the crucial point for my purposes is that it will, if sound, have rather broader implications than robson himself suggests. consider that, as i have already argued elsewhere (in robson ( )) god’s mind would need to incorporate representations of some truly unspeakable ugliness regardless of the stance we take with respect to divine ersatzism. after all, the actual world contains its own share of horrors – the atrocities committed by the actual world’s nazi party, the transatlantic slave trade, and the disastrous consequences of mao’s ‘great leap forward’ to name but a few – and god, qua omniscient being, would need to have perfectly detailed representations of each of these in his mind. the theist cannot, after all, accept aristotle’s ( / : ) dictum that for god it would be ‘better not to see some things than to see them’ or his corresponding belief that there will be some matters about which god remains ignorant. rather, god will possess excruciatingly detailed representations of these horrors regardless of the view we adopt with respect to divine ersatzism. as such, it seems that, if robson’s line of reasoning with respect to possible worlds is cogent, there will be a clear tension between the claim that god is omniscient and the claim that he is perfectly beautiful. one solution here is to treat this as a reductio of robson’s original claim that god’s possessing representations of, a certain kind of, unspeakable ugliness entails that he is not himself perfectly beautiful. and there seem (as i discussed in robson ( )) to be various reasons why someone might reject this claim. first, it could be argued that god’s being perfectly beautiful is compatible with his having some parts which are not beautiful (and, indeed, with his having some which are horrifically ugly). it is, after all, common for an object as a whole to be made more beautiful by virtue of some aspect which would, considered in isolation, be very ugly. consider, for example, the way in which the easter narrative is made more beautiful by the inclusion of some of its darker aspects. second, it might be objected that there is an important distinction between a representations’s being of something with a particular aesthetic character and the representation itself possessing that character. van gogh’s pair of shoes has, for example, attracted a great deal of interest for providing a very beautiful representation of an aesthetically unremarkable object. that said, it is important to note that both of these responses to robson’s argument rely on controversial claims regarding the aesthetic which robson himself argues in a later paper (robson ) we should reject. i will not, however, attempt to evaluate robson’s responses here since my primary concern is not with whether we should endorse robson’s claims regarding ersatz possible worlds but, rather, with what implications his arguments have for our understanding of omni-beauty and omniscience. importantly, it seems that anyone who wants to accept that god instantiates both attributes must also accept at least one of the claims discussed in the previous paragraph. that is, they must either allow that god’s being perfectly beautiful is compatible with his having some parts which would, if considered in isolation, be ugly or that a representation of even a horrifically ugly event need not itself be ugly. and either of these would tell us something important concerning the nature of beauty. further, such conclusions will also have important consequences concerning our understanding of the divine nature. consider, for example, that if we accept that god has beliefs which by themselves would be ugly but which, as a part of the divine nature, contribute to the greater beauty of the whole then this would itself tell us a great deal about the nature of god’s beauty. in particular, it would entail that he is not, as robson ( : ) maintains ‘wholly and completely beautiful’ in the sense that ‘there can be no ‘part’ of god that is not (so to speak) crammed full of beauty’. rather, his surpassing beauty would arise (as i tentatively suggest elsewhere) from ‘placing something which is, in and of itself, very ugly in certain relations to a greater whole’ in order to ‘give rise to a strange kind of beauty, a beauty that is often wonderfully exquisite’ (robson : ). beyond that, it would also seem to generate a conflict with another putative divine attribute; simplicity. many theists will resist the idea that god (qua perfectly simple being) has any parts at all but this account appears committed to the claim that he has genuinely distinct parts of varying aesthetic character. of course, it is open to the defender of such a view to argue that this commitment is merely superficial and that the spirt of these claims can be rephrased in a way which avoids commitment to god’s genuinely having parts. if, however, such paraphrase strategies prove unsuccessful, then this would generate a tension between the doctrine of divine simplicity and the claim that god is perfectly beautiful. turning to the second claim, if we attempt to avoid the potential conflict here by allowing that representations of horrific ugliness, of certain kinds, can themselves be non-ugly (and perhaps even beautiful) then this tells us something important about the kinds of representation which exist in the divine mind. specifically, it tells us that god’s beliefs (along with his other representational mental states) must be of one of these kinds rather than of some other kind which does not allow for such an aesthetic disconnect between representation and represented. some will likely also regard this claim as an additional motivation for adopting the traditional thomist view according to which all of god’s beliefs are, in some sense, about himself. that is, as aquinas ( / : ) puts things, that god only directly knows his own nature but that ‘by understanding himself, understands every creature’. if this is right, then god wouldn’t have beliefs which are straightforwardly about the various (horrifically ugly) atrocities discussed above but, rather, beliefs about his own (perfectly beautiful) nature which somehow allow him to be cognisant, albeit indirectly, of these other matters as well. as it stands, though, such a view is little more than a placeholder solution and we would need to hear much more about why it is that, say, a direct belief concerning a historical genocide would of necessity be ugly whereas a belief which arises via divine self- contemplation need not be. providing any answer to such questions would, however, require far too lengthy a diversion into the intricacies of thomist philosophy. whatever we ultimately say about such matters, though, it is clear that exploring the relationship between omniscience and omni-beauty will have important consequences for our understanding of the divine nature. omni-beauty and sovereignty the claim that god is perfectly beautiful also has some important consequences for our understanding of divine sovereignty. i argued above that a view according to which god is merely the causal source of all beauties (distinct from himself) isn’t sufficient to explicate the popular notion that he is the wellspring of all beauty. yet, even this limited claim may prove problematic. as mentioned above, god is standardly taken to be the creator of all objects – beautiful or otherwise – distinct from himself, but this claim has been questioned of late. a number of contemporary philosophers (such as wolterstorff ( ) and van inwagen ( )) have argued that there are certain abstract objects which are distinct from god and yet not dependent on god for either their existence or nature. however, such philosophers standardly aim to retain the traditional claim that god is sovereign creator of all things by understanding this claim as ‘containing a tacitly restricted quantifier [...] to objects that can enter into causal relations’ such that ‘god is the creator of all things (besides himself) that can in some sense be either causes or effects’ (van inwagen : ). a problem arises, though, when we try to combine this view with the claim that god is the causal source of all beauty, since it appears to be the case that, as already discussed above, we frequently attribute beauty (and other aesthetic properties) to abstracta. and, if taken at face value, these attributions would seem to highlight a tension between restricted understandings of divine sovereignty and omni-beauty. after all, if abstracta, and their aesthetic properties, really are outside the control of god then he cannot even be the causal source of their beauty. further, the worry here seems to be particularly pressing with respect to omni-beauty since equivalent problems are not faced by parallel accounts concerning, for example, god’s omnipotence, omniscience or omnibenevolence. we could, after all, accept the restricted sovereignty view while still allowing that god is the source of all power, knowledge, moral goodness, and so forth since abstracta are typically taken to be incapable of instantiating such properties. an obvious response here would be to claim that these cases actually are analogous and that abstracta aren’t genuinely capable of instantiating aesthetic properties. one popular motivation for adopting this view is that abstract objects are not straightforwardly perceivable by means of the senses but, of course, this response is not available to advocates of the omni- beauty view since they are already committed to rejecting such general limitations on the scope of the aesthetic. still, there are other reasons – besides such a general prohibition – why we may not wish to take such apparent aesthetic attributions at face value. in particular, some philosophers have recently argued that claims which apparently attribute aesthetic properties to abstracta should merely be taken as a shorthand for some non-aesthetic claim(s). j.w. mcallister ( ), for instance, argues that talk of ‘beauty’ in mathematics is reducible to claims concerning simplicity. assuming that we do accept that some abstracta have genuine aesthetic features, though, a range of options are still open to advocates of the omni-beauty view. first, they could accept the restricted sovereignty account and apply a similar restricted quantification strategy to the claim that god is the source of all beauties other than his own (maintaining that god is e.g. the source of beauty in all beautiful objects besides himself which can be either causes or effects). however, restrictions of this kind will likely be met with suspicion by many of those who have stressed the importance of god’s role as the source of beauty. alternatively, they could adopt any one of a range of other accounts of god’s relationship to abstract objects, all of which avoid such difficulties. maintaining, for example, that abstracts are either not distinct from god (perhaps because they are as, e.g., plantinga ( ) suggests, part of god’s nature) or else not outside of the scope of divine control (as suggested by theistic activists such as morris and menzel ( )). the point remains, though, that while there is no straightforward conflict between divine sovereignty and the claim that god is the source of all beauty, the latter will have important consequences for our understanding of the former. where to now? this paper has been an attempt to reignite discussion of how best to analyse the neglected claim that god is perfectly beautiful as well as an exploratory foray into considering the wider implications of such a view for a range of contemporary debates. i have assumed throughout this paper that we should take the apparent attributes of perfect beauty to god found within scripture and tradition at face value, and that we should endorse such attributions. that is, i have assumed that omni-beauty is a genuine divine attribute. this claim is, however, likely to prove controversial (even amongst theists) and there may well be some significant costs to adopting such a view. indeed, many will likely regard some of the consequences i have highlighted above as prohibitively costly. for the purposes of this paper, though, i take no stance with respect to such debates. while, for the record, my own view is that omni-beauty is a genuine divine attribute, i have not attempted to argue for this claim here. instead, my aim has been to establish two rather more modest claims. first, that the project of defining what precisely it means for god to be perfectly beautiful is not as straightforward as it might initially appear (with a number of prima facie promising strategies for doing so quickly encountering difficulties). second, that claims concerning god’s omni-beauty have important and wide-reaching consequences for, inter alia, key debates within aesthetics and the philosophy of religion. my hope is that, by highlighting these two facts, i will have gone some way towards 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( ) ‘thomas aquinas and participation’, in j. f. wippel (ed.) studies in medieval philosophy (washington, dc: catholic university of america press), - . wittgenstein, ludwig ( / ) tractatus logico-philosophicus (new york, dover). wolterstorff, nicholas ( ) on universals: an essay in ontology (chicago, university of chicago press). wynn, mark ( ) ‘beauty, providence and the biophilia hypothesis’, the heythrop journal, , - . zagzebski, linda trinkaus ( ) the dilemma of freedom and foreknowledge (oxford, oxford university press). zangwill, nick ( ) ‘are there counterexamples to aesthetic theories of art?’, the journal of aesthetics and art criticism, , - . all quotes are from the new american standard version. something which has already been noted in e.g. robson ( : ). it is true that there has recently been a resurgence of interest with respect to aesthetic issues within the philosophy of religion. however, such work has tended to focus on concerns such as the aesthetic character of religious art (harries ), expressions of god’s beauty in the natural world (wynn ), aesthetic arguments for existence of god (de cruz & de smedt ), or the beauty of religious exemplars (kidd ) rather than specifically on the beauty of god. a related, purely exegetical, response denies that some of these sources genuinely attribute beauty to god. it is, after all, a controversial matter whether ‘beauty’ is the best translation of the relevant terms in the hebrew texts quoted above and similar concerns apply with respect to the appropriate translations of a number of works within the tradition. such a response would, however, be rather limited since it is clear (modulo certain concerns addressed below) that many writers within the tradition do make such attributions. explanations of this kind are not without precedent. peter geach ( : ), for example, argues that hobbes and mctaggart adopted positions of this kind with respect to god’s putative omnipotence. for some extended discussions of accounts of god’s beauty within the tradition see, e.g., von balthasar ( ), eco ( ), delattre ( ), and sherry ( ). one (partial) explanation may be that the neglect of this topic is part of a wider neglect of beauty in much recent aesthetic theorising (see, e.g., mothersill ( )). of course the division here between literal and metaphorical interpretations is by no means exhaustive. one could, for example, interpret the relevant talk as analogical or as an imperative to adopt some particular attitude towards god. i will, however, ignore such complications in what follows since my interest will be in how best to interpret these claims when taken as straightforwardly literal attributions of beauty to god. it is, after all, consistent to claim that something is more beautiful than any other individual object but less beautiful than some collection of such objects. i will omit explicit reference to this complication in what follows. indeed, some have argued that it is only physical objects that are genuinely capable of instantiating aesthetic properties such as beauty. however, the theist who attributes omni-beauty to god will – as i discuss further below – already be committed to rejecting such a restricted view of the scope of the aesthetic. this is, for example, a key motivation behind geach’s ( ) account of god’s power. and parallel moves have been made with respect to god’s other perfections (see e.g. pseudo- dionysius ( : ) on god’s wisdom and geach ( ) on his power). a view which has pre-christian precursors in, for example, the writings of plato and plotinus. such a view would, of course, fit particularly well with an influential family of views which treats ugliness as merely a privation of (divine) beauty. for more on the thomist view here see wippel ( ) and alston ( ). for discussion of some alternative accounts see tweedale ( ). though it is much more controversial whether this also commits us to the existence of some object (a universal say) which is identical with that property. i take no stance on that issue here. someone who adopted a version of error theory combined with some form of fictionalism could incorporate the claim that god is omni-beautiful into her fiction (a move, no doubt, made even easier if she also accepts some form of fictionalism regarding religious matters). i will, however, presuppose within this paper that claims regarding the beauty of god are not made within any kind of fictionalist or instrumentalist framework. a more defensible (though i believe mistaken) position, advocated by, e.g., zangwill ( : ), is that beauty and ugliness are the only genuine aesthetic properties and that other putative aesthetic properties ‘[d]aintiness, dumpiness, elegance, balance, and delicacy are all ways of being beautiful or ugly.’ mind independence (or at least independence from human minds) is crucial here since, i assume, no orthodox theist will be willing to allow that god’s beauty is constitutively dependent on the reactions of human observers. indeed, some versions of the view are even narrower than this. roger scruton ( : ), for example, argues that the so called ‘lowers senses’ (such as smell and taste) aren’t genuinely aesthetic. aquinas might be seen as advocating an even more restricted view given his famous claim that the beautiful is that which gives pleasure when seen. however, i side with those (such as maritain ( : )) who interpret this use of ‘seen’ not to refer exclusively to visual perception but, rather, to include also (and perhaps primarily) various kinds of intellectual insight. for discussion of the nature and consequences of such views see, e.g., kölbel ( ), baker ( ) and palmira ( ). robson and baker ( ) propose a view of faultless disagreement in aesthetics according to which both parties believe claims which are, strictly speaking, neither true nor false. most prominently max kölbel ( ; ). nor will i pursue the putative tension between divine simplicity and the beauty of god discussed in baddorf (forthcoming). for further discussion of such views see, e.g., collinson ( ), tanner ( ) and the essays in levinson ( ). there are, of course, a number of different variations of this view (as discussed in, e.g., adams ( ), leftow ( ) and kraay ( )) but i will not consider how best to spell out the details of such a view here. in robson’s original paper ( : - ) he argues against attempts to expand the scope of his claims in this way. however, i argue (robson : - ) that his arguments to this effect are unsuccessful. of course, many theists will (for reasons i discuss further below) be inclined to resist the claim that god literally has parts. for an interesting discussion of this phenomena see fields ( ). for a discussion of this case see sassen ( ). another option would be to deny that anything in the world is genuinely ugly but this view is (in contrast with the influential leibnizian view according to which the ugliness of these parts contributes to the greater beauty of the world as a whole) implausible in the extreme. there are, of course, difficulties (as described in, e.g., alston ( ) and zagzebski ( : - )) with ascribing god beliefs of any kind given this thomist view. i will, however, ignore such complications here. an easier response here might be to claim that the relevant representations aren’t beautiful but, rather, that (contra robson) they simply aren’t appropriate objects for aesthetic evaluations (and so are neither beautiful nor ugly). i thank an anonymous referee from the journal for drawing my attention to this point. though there are (as discussed in, e.g., craig and ) other worries concerning the restricted sovereignty view. and, of course, there is always the option of resolving this conflict by denying (as, e.g, craig ( ) and ( ) has) that such abstract objects even exist. for what it’s worth, my own view on this issue is that (for reasons highlighted in, e.g., breitenbach ( )) such paraphrases strategies are unconvincing and that we ought to take these apparently aesthetic attributions at face value. i will not, however, attempt to resolve such debates here. which is not, of course, to suggest that they encounter no difficulties of their own (see the papers in gould ( ) for discussion of a range of views concerning the relationship between god and abstract objects). i would like to thank audiences at the university of leeds and the university of nottingham, as well as an anonymous referee for the journal, for their useful comments on earlier versions of this paper. special thanks to danielle adams, sarah adams, ian kidd, emily paul, and mark wynn for their very helpful feedback. perception, , volume , pages - the illusion of beauty n k humphrey sub-department of animal behaviour, university of cambridge, madingley, cambridge cb aa based on a lecture at the institute of contemporary arts, november "beauty is truth, truth beauty" to the poet. but a biologist is bound, i think, to regard beauty—at least man-made beauty—as something closer to a lie. a lie, admittedly, of a unique kind, but a kind to which both men and animals are specially vulnerable. if i give a hungry dog a solution of saccharine it will lap it up; if i show a cock robin a bundle of feathers with a red patch on its underside the robin will attack it; and if i show a man an abstract painting or play him a piece of music he will, if he thikks it beautiful, stop to watch or listen. there is, i believe, a formal similarity in all these cases. in each we have an animal performing a useful and relevant piece of behaviour towards an inappropriate sensory stimulus. but there is, i agree, a rather basic difference, namely that in the first two cases we have a good scientific explanation of what is going on, while in the third we're almost ignorant. with the saccharine and the red-breasted bundle of feathers we know what the artificial, 'illusory', stimulus corresponds to in nature and we know how the dog's or the robin's behaviour would in normal circumstances contribute to its biological survival. n k humphrey saccharine tastes like sugar and it is biologically adaptive for a hungry dog to eat sugar; the bundle of feathers looks like another male robin and it is biologically adaptive for a robin to drive an intruder from his territory. but in the case of man's response to a beautiful work of art we have no clear idea either of what the work of art corresponds to in nature, nor of why it should be biologically adaptive for men to like the natural counterpart (whatever it may be). it is with these fundamental questions of the biology of aesthetics that my paper is concerned. i plan first to try to define the particular quality which things of beauty have in common, and then to suggest a possible reason why men—and, for that matter, animals—should be attracted to the presence of that quality. seventy years before darwin published the origin of species the scottish philosopher thomas reid suggested how a modern biologist might proceed: "by a careful examination of the objects to which nature hath given this amiable quality [of beauty], we may perhaps discover some real excellence in the object,- or at least some valuable purpose that is served by the effect which it produces upon us. this instinctive sense of beauty, in different species of animals, may differ as much as the external sense of taste, and in each species be adapted to its manner of life" (reid, ). yet it is easy to dismiss reid's manifesto. the injunction to 'examine carefully' the objects of beauty would be fine were it true that different individuals of the same species did find the same objects beautiful. but one of the central problems of aesthetics has always been that, in man at least, there is no clear consensus. the point was forcefully made by maureen duffy in her review of jane goodall's book in the shadow of man. jane goodall had written "but what if a chimpanzee wept tears when he heard bach thundering from a cathedral organ?", to which miss duffy replied "what indeed if an amazon pigmy or a th century factory hand wept tears at such a minority western cultural phenomenon?". the way out for some critics confronted with the diversity of individual taste has been to react with the cynicism of clive bell, stating that "any system of aesthetics which pretends to be based on some objective truth is so palpably ridiculous as not to be worth discussing" (bell, ). but william empson ( ) scorned such anti- rationality: "critics", he wrote, "are of two sorts: those who merely relieve themselves against the flower of beauty, and those, less continent, who afterwards scratch it up. i myself, i must confess, aspire to the second of these classes; unexplained beauty arouses an irritation in me..." my own sympathies lie, of course, with empson. but the roots of the flower of beauty may go deep and if we are to expose them undamaged we should start scratching at some distance from the stem. the problem of looking for common principles behind apparent diversity is not peculiar to aesthetics. very similar problems have arisen in other disciplines, notably in linguistics and in anthropology. the breakthrough in these fields came through applying the methods of structuralism. i believe that a structuralist approach is the key to a science of aesthetics. in his discussion of the analysis of myth, levi-strauss ( ) wrote as follows: "for the contradiction which we face is very like that which in earlier times brought considerable worry to the first philosophers concerned with linguistic problems... ancient philosophers did notice that certain sequences of sounds were associated with definite meanings, and they earnestly aimed at discovering the reason for the linkage between these sounds and that meaning. their attempt however was thwarted from the beginning by the fact that the same sounds were equally present in other languages although the meaning they conveyed was entirely different. the contradiction was surmounted only by the discovery that it is the combination of the illusion of beauty sounds, not the sounds themselves, which provides the significant data". he went on: "if there is a meaning to be found in mythology, it cannot reside in the isolated elements which enter into the composition of a myth, but only in the way those elements are combined". following this lead, it would seem fruitful to search for the essence of beauty in the relations formed between the perceived elements. as it happens, just such an approach was proposed in by the philosopher herbart: "the conclusion is that each element of the approved or distasteful whole is, in isolation, indifferent; in a word, the material is indifferent, but the form comes under the aesthetic judgement .... those judgements which are commonly conceived under the name of taste are the result of the perfect apprehension of relations formed by a complexity of elements". but it is one thing to point to the importance of relations, another to say what relations are important and another still to say why. levi-strauss himself, in so far as he has had anything to say about aesthetics, has tended to regard works of art merely as a special sort of myth. for him the work of art is a "system of signs" which conveys a message. to understand the message we must make an equation between the relations among the signs and the relations among the things signified. no doubt such myth-like works of art exist. we know for instance of a chinese scholar, lyng lun, who years before christ strung together five tones of oriental music, explained them, formed them into a system, and gave them strange names, every tone being called after a social stratum from the emperor down to the peasant: kong, the emperor; chang, the minister; kyoy the burgher; tchiy the official; yu, the peasant (pahlen, ). within such a system almost any piece of music must, if interpreted in a structural way, have carried a potential social message. in the field of graphic art, caroline humphrey ( ) has recently shown how the magical drawings of the mongolian buryat people embody structuralist devices which make the drawings effectively into 'visual texts'. and almost certainly similar sign- systems are at work within the mainstream of western painting. mcmanus and i found evidence that rembrandt, for instance, may have made use of a simple sign system in his painted portraits, whereby the social status of the subject of the portrait was indicated by the left or right turn of his head (humphrey and mcmanus, ). but be that as it may, these sign systems where they exist serve primarily a semantic function, not an aesthetic one. they do not lend beauty to a work of art. if structuralism is to help in pointing to relations which are aesthetically satisfying it must take a different turn. few people have written with more insight about beauty than the poet gerard manley hopkins. hopkins is hardly to be called a 'structuralist' since the name had still to be invented in his lifetime, yet not only did he see that the essence of beauty lies in certain relations but he attempted explicitly to define what those relations are. in he wrote a paper for his tutor at oxford in the form of a 'platonic dialogue' between a student and a professor in a college garden. the two of them fall to discussing the beauty of the garden and they dwell in particular on the leaves of a chestnut tree. the professor holds forth on the structural relations within the chestnut-fan, pointing out how each leaf is a variation with a difference of the common pattern, how the overall shape of the fan shows mirror symmetry, the left half being a perfect reflection of the right, whilst in other ways the internal reflections are tantalisingly irregular—each of the large oblique leaves, for instance, being reflected by an exact copy of itself in miniature; and he discusses too the relation between the leaves of the chestnut and the leaves of other trees, drawing attention to the way in which the chestnut leaf, being fatter at the distal than the n k humphrey central end, is the opposite shape to the common shape shown, say, by the leaf of an elm. the professor continues: "then the beauty of the oak and the chestnut-fan and the sky is a mixture of likeness and difference or agreement and disagreement or consistency and variety or symmetry and change". "it seems so, yes". "and if we did not feel the likeness we should not feel them so beautiful, or if we did not feel the difference we should not feel them so beautiful. the beauty we find is from the comparison we make of the things with themselves, seeing their likeness and difference, is it not?". before long they move on to the subject of poetry: "rhythm therefore is likeness tempered with difference .... and the beauty of rhythm is traced to the same causes as that of the chestnut-fan, is it not so?" .... "what is rhyme? is it not an agreement of sound—with a slight disagreement?".... "in fact it seems to me that rhyme is the epitome of our principle. all beauty may by a metaphor be called rhyme, may it not?". in christiansen coined the word "differenzqualitaat" to refer to what hopkins had called "likeness tempered with difference". and shortly afterwards the writers of the school of russian formalism propounded a system of aesthetics based on essentially similar structuralist ideas. in england the philosopher whitehead wrote of rhythm: "the essence of rhythm is the fusion of sameness and novelty; so that the whole never loses the essential unity of the pattern, while the parts exhibit the contrast arising from the novelty of their detail. a mere recurrence kills rhythm as does a mere confusion of differences. a crystal lacks rhythm from excessive pattern, while a fog is unrhythmic in that it exhibits a patternless confusion of detail" (whitehead, ). here then we have the beginnings of an answer as to what relations lie at the heart of beauty. "all beauty may by a metaphor be called rhyme". what is rhyme like? well, let us have an example: cat rhymes with mat, cat does not rhyme with table, cat does not rhyme with cat. taking rhyme as the paradigm of beauty, let me turn at once to the fundamental question: why do we like the relation which rhyme epitomises? what is the biological advantage of seeking out rhyming elements in the environment? the answer i propose is this: considered as a biological phenomenon, aesthetic preferences stem from a predisposition among animals and men to seek out experiences through which they may learn to classify the objects in the world about them. beautiful 'structures' in nature or in art are those which facilitate the task of classification by presenting evidence of the 'taxonomic' relations between things in a way which is informative and easy to grasp. three steps are needed to justify this argument. first, an explanation of why classification should be important to biological survival. second, an explanation of why particular structures such as those exemplified by rhyme should be the best way of presenting material for classification. third, evidence that men and animals have a propensity to classify things and that they are attracted in particular to the presence of rhyme. why is classification important? in order to be effective agents in the natural world, animals require the guidance of a 'world model', an internal representation of what the world is like and how it works. this model enables them to predict in advance the characteristics of the illusion of beauty 'recognisable' objects, to anticipate the likely course of events in the environment, and to plan their behaviour accordingly. the role of classification in this context is to help organise sensory experience and to introduce an essential economy into the description of the world. an effective classification system is one which divides the objects in the world up into discrete categories according to criteria which make an object's membership of any particular class a relevant datum for guiding behaviour: the objects in any one class may differ in detail but they should share certain essential features which give them a common significance for the animal. such a classification system will reduce the 'thought load' on the animal, expedite new learning and allow rapid and efficient extrapolation from one set of circumstances to another. we may be sure that any animal which could not or did not classify things effectively—which could not recognise the likenesses between things—would not have a chance of surviving for long. and so, in the course of evolution, there must have been very strong pressures on animals to perfect techniques of classification, on a par perhaps with those that have made eating and sex evolve into such efficient and dominant activities. i shall argue that, just as with eating or with sex, an activity as vital as classification was bound to evolve to be a source of pleasure to the animal. both animals and men can, after all, be relied on to do best what they enjoy doing. but i am anticipating. the next step of the argument is to demonstrate the relevance of rhyme. on what kind of 'evidence' are classification systems based? the young animal's task of imposing a system of categories upon the world is comparable to that which faces a zoological taxonomist when he sets out to classify the animal kingdom. we may assume that the goal before the animal is in some sense 'given', that he has an innate predisposition to develop a system of categories, but that the actual system he arrives at must be largely based upon his own experience. how does the animal—and the zoologist—proceed? i would suggest he works through the following stages: (i) he makes a preliminary reconnaissance and from this forms certain hunches about how his world is constituted, what kinds of classes of objects it contains and what are the distinguishing criteria, (ii) he seeks further evidence to test the 'validity' of these criteria and at the same time to acquaint himself with the diversity which may exist within each class, (iii) to the extent that his criteria prove successful he adopts them as permanent guidelines for future classification, while to the extent that they fail he abandons or revises them. successful criteria will on the whole be those which yield a system of classification which is at once unambiguous, i.e. objects belong to one class only; exhaustive, i.e. every object belongs to some class or another; and useful, i.e. objects in the same class may be treated for some practical purpose as identical. thus a zoologist who comes up with a simple classification of animals which divides them into two classes, vertebrates and invertebrates, has produced a scheme which meets all three requirements. but a division of animals into meat-eaters and plant-eaters, for example, fails to be unambiguous since there are some animals which eat both; a division into swimming animals and flying animals fails to be exhaustive since there are some animals which neither swim nor fly; a division into animals which live in zoos and animals which live freely fails to be useful since there is no purpose (for a zoologist) in treating the members of either of these classes as identical. i want to examine the process of seeking evidence to test the criteria for distinguishing between classes. let me continue with a zoological example. imagine n k humphrey that the taxonomist is concerned to classify warm-blooded vertebrates. in making a preliminary survey he meets a cat, a dog, and a hen, and he notices that the cat and the dog are covered with hair whilst the hen is covered with feathers. on this basis he sets up two putative classes, called mammals and birds, defined respectively as animals which have hair and as animals which have feathers. his next step is to look for further examples to test his ideas. suppose that the next animal he meets is a horse and then a rabbit. applying his criteria he discovers that these animals fit neatly into the category of mammals. then perhaps he meets a sparrow, then a mouse, and then a parrot and he is pleased to find that whilst the mouse is clearly a mammal the sparrow and the parrot fit the definition of a bird. looking further he meets another cat, but on this occasion he pays it little attention since it tells him nothing new. and later on he meets an octopus, but since this is not a warm-blooded vertebrate it can provide no evidence either way and again he shows no interest in it. slowly, by accumulating evidence, he establishes that his criteria do indeed serve to make unambiguous distinctions, and at the same time he becomes familiar with the range of different animals that fall within each class. it remains of course for him to show that his classification is a useful one, i.e. that it serves some purpose to group mice and horses or hens and parrots together. certain principles of how to gather evidence emerge. the zoologist needs to prove that his criteria serve both to group different animals together and to separate one group from another. accordingly he looks for two kinds of examples: (i) sets of animals which share a particular distinctive feature, and (ii) other sets of animals which share a contrasting feature. thus he looks in effect for 'likeness tempered with difference', 'rhyme', and for contrast between sets of rhyming elements. but he is not interested in seeing repetitive examples of the same animal, nor in seeing an animal which is altogether different from the others and thus lies beyond the scope of his classification—"a mere recurrence kills rhyme, as does a mere confusion of differences". pursuing this metaphor of the taxonomic 'poem': horse 'rhymes' with dog, hen 'rhymes' with parrot, horse and dog contrast with hen and parrot, horse does not rhyme with horse, nor hen with hen, neither horse nor dog nor hen nor parrot rhyme or contrast in a relevant way with octopus. now to the nub of my argument. i believe that the same principles which apply to the zoological taxonomist apply to every animal who needs to classify the world about him. if it is helpful for the taxonomist to look for 'rhymes' in his materials, so it is helpful for the animal to do so. it is for this reason that we have evolved to respond to the relation of beauty which rhyme epitomises. at one level we take pleasure in the abstract structure of rhyme as a model of well-presented evidence, and at another we delight in particular examples of rhyme as sources of new insight into how things are related and divided. let me move on to the next stage of the argument and give evidence that men and animals do indeed take pleasure in classifying things and, on that account, are especially attracted to rhyme. the propensity to classify-—and the love of 'rhyme' aristotle once condescendingly remarked "learning is very agreeable, not only to philosophers but also to other men" (poetics iv). what evidence is there that classification—the core of learning—is agreeable to men and to animals also? the illusion of beauty for experimental evidence of a general kind we may look to the many studies of exploratory behaviour. comparative psychologists have found that, in almost every species studied, animals will work to be exposed to novel sensory stimuli. indeed, 'stimulus novelty' is the most universal reinforcer of behaviour which is known. in my own work with monkeys i have found that monkeys will even work to look at abstract paintings and prefer such pictures to pictures of appetising, but familiar, food. recent experiments strongly suggest that when monkeys work to look at pictures they do so because the picture presents them with a challenge to incorporate new material into their model of the world: pictures of familiar objects hold their attention far less long than pictures of objects for which they have no readily available category. but while they do not spend long on thoroughly familiar things, neither, i should say, are they interested in looking at a total jumble. and that leads me on to the question of rhyme. the significance of rhyme was in fact recognised by experimental psychologists some time ago, though they called it—and still call it—by the cumbersome name of 'stimulus discrepancy'. in the early s a theory was propounded called the 'discrepancy theory', the gist of which is that men who have been exposed for some time to a particular sensory stimulus respond with pleasure to minor variations from that stimulus (mcclelland et al, ). and confirmatory evidence has come from a number of studies. for instance, human babies who have been made familiar with a particular 'abstract' visual pattern take pleasure in seeing new patterns which are minor transformations of the original (kagan, ). among animals, it has been shown, for instance, that chicks who have been 'imprinted' early in life on an artificial stimulus soon come to prefer new stimuli which are slightly different from the one they are familiar with (bateson, ). neither babies nor chicks are attracted to stimuli which are wholly unrelated to what they have already seen. i am pursuing my own research with monkeys along these lines. but this is not the place to report the details of experiments. and it is not in fact to experimental evidence that i want to give most weight in this discussion. for there is much in the evidence of anecdote and common experience to substantiate the view that men, at least, take pleasure in one form or another of classificatory activity. as we might expect, the tendency is most pronounced in children. children have a thirst to know 'what things are'. they love especially to learn names , and to prove the power of their vocabulary with new examples. picture books for children often serve no other purpose than as practical exercises in classification. the same animals—rabbits, hens, pigs—appear in the pictures again and again. "where's the bunny?" asks the child's mother, and with a smile of pleasure the child points a finger to yet another rabbit which rhymes with those he has already seen. the ability to name becomes tangible evidence of the ability to classify, and when the name for an object is not available children will often invent their own. the poet richard wilbur tells this story: "... i took my three-year-old son for a walk in the lincoln woods. as we went along i identified what trees and plants i could .... after a while we came to a stretch of woods-floor thick with those three-inch evergreen plants one sees everywhere in new england woods, and i was obliged to confess i didn't know what to call them. my three-year-old stepped promptly into the breach. 'they're millows', he told me, 'look at all the millows'. no hesitation; no bravado; with a serene adamite confidence he had found a name for something nameless and brought it under our verbal control. millows they were" (wilbur, ). yet while children may manifest the tendency most clearly, adult men often show an equally innocent delight in classifying, not least in naming. a poem by robert bridges called "the idle flowers" mentions different flowers by name in a poem only lines long! and the reverse of the coin is the ridicule that is heaped on n k humphrey people who make mistakes with names. a. p. herbert tells a story against himself, again to do with flowers: " t h e anemias are wonderful', i said, 'and those arthritis, always so divine at this time of the y e a r ' " (quoted in hadfield, ). the concern with naming, carried to such an extreme in bridge's poem, finds echoes in another remarkable aspect of human behaviour—the passion for collecting. collecting, whether the material of the collection be postage stamps, antiquarian books or engine numbers, is to my mind yet another manifestation of the pleasure men take in classification. curiously, there is only one psychologist i know of who has deemed collecting worthy of comment. that man, surprisingly enough, is pavlov. in an essay called "the reflex of purpose" he characterised collecting as "the aspiration to gather together the parts or units of a great whole or of an enormous classification, usually unattainable", and went on: "if we consider collecting in all its variations, it is impossible not to be struck with the fact that on account of this passion there are accumulated often completely trivial and worthless things, which represent absolutely no value from any point of view other than the gratification of the propensity to collect. notwithstanding the worthlessness of the goal, every one is aware of the energy, the occasional unlimited self-sacrifice, with which the collector achieves his purpose. he may become a laughing-stock, a butt of ridicule, a criminal, he may suppress his fundamental needs, all for the sake of his collection" (pavlov, ). collecting, though its practitioners are not usually credited with aesthetic sensitivity, is not, i believe, far removed from the appreciation of beauty. consider for a moment the nature of a typical collection, say a stamp collection. postage stamps are, in structuralist terms, like man-made flowers: they are divided into 'species', of which the distinctive feature is the country of origin, while within each species there exists tantalising variation. the stamp collector sets to work to classify them. he arranges his stamps in an album, a page for the species of each country. the stamps on each page 'rhyme' with each other, while they contrast with those on other pages. but pavlov was right: stamp collecting is a worthless activity. as we have moved through my examples, from an infant animal learning to recognise the objects in the world about him, to a child learning to name pictures in a book, to a man sticking stamps in an album, we have moved further and further from activities which have any obvious biological function. they are all, i submit, examples of the propensity to classify, but with each example the classification seems to have less and less direct survival value. we should not be surprised. earlier, i compared the pleasure men get from classification with the pleasure they get from sexual activity. now, though sex has a clear biological function, it goes without saying that not every particular example of sexual activity has in fact to be biologically relevant to be enjoyable. indeed, much human sexual activity takes place at times when the woman, for natural or artificial reasons, is most unlikely to conceive. and so too the process of classification may give pleasure in its own right even when divorced from its proper biological context. once nature had set up men's brains the way she has, certain 'unintended' consequences followed—and we are in several ways the beneficiaries. so let me turn, at last, to beauty—to examples of rhyme and contrast which people deem aesthetically attractive. i want first to consider not 'works of art' but certain natural phenomena which men call beautiful and yet which have no 'natural' value to us. among the wealth of examples of beauty in nature, i shall choose the case of flowers. flowers have an almost universal appeal, to men of all cultures, all classes, and all ages. we grow them in gardens, decorate our houses and our bodies with the illusion of beauty them, and above all value them as features of the natural landscape. they are regarded indeed as paragons of natural beauty, and i believe it is no accident that they are so admired, for in at least three ways flowers are the embodiment of 'visual rhyme'. consider first the static form of a simple flower such as a buttercup or daisy. the flower-head consists of a set of petals arranged in radial symmetry around a cluster of stamens, and the flower-head is carried on a stalk which bears a set of leaves. petals, stamens, and leaves form three sets of contrasting rhyming elements: each petal differs in detail from the other members of its class yet shares their distinctive shape and colour, and the same is true for the stamens and the leaves; the features that serve to unite each set serve at the same time to separate one set from another. secondly, consider the flower's kinetic form. the living flower is in a continual state of growth, changing its form from day to day. the transformations which occur as the flower buds, blossoms, and decays give rise to a temporal structure in which each successive form rhymes with the preceding one. thirdly, consider groups of flowers. typically each flowering plant bears several blooms, and plants of the same species tend to grow in close proximity, so that we are presented with a variety of related blooms on show together. but, more than this, groups of flowers of different species commonly grow alongside one another—daisies and buttercups beside each other in the field, violets and primroses together in the hedgerow. thus while the flowers of one species rhyme with each other the rhyme is given added poignancy by the contrasting rhymes of different species. it is this last aspect that perhaps more than anything makes flowers so special to us. the flowers of different species are of necessity perceptually distinct in colour, form, and smell in order that they may command the loyalty of pollinating insects. men neither eat their pollen nor collect their nectar, yet flowers provide us with a kind of nourishment—food for our minds, ideally suited to satisfy our hunger for classification. but flowers have no monopoly of natural beauty. in fact almost wherever we come across organic forms we discover the structure of visual rhyme. long before architects invented the module, nature employed a similar design principle, basing her living creations on the principle of replication—at one level replication of structural elements within a single body, and at another replication of the body of the organism as a whole. but, at either level, the replicas are seldom, if ever, perfect copies: in the leaves of a tree, the spots of a leopard, the bodies of a flight of geese, we are presented with sets of 'variations on a theme'. and it is not only among living things we find such structures, for inanimate objects too tend to be shaped by physical forces into 'modular' forms—mountain peaks, pebbles on a beach, clouds, raindrops, ocean waves—each alike but different from the others. thus, through its varied but coherent structure, a natural landscape can match the rhythmic beauty of a gothic church. or of a musical symphony. my discussion of 'art' must inevitably be brief, and i shall in fact take music as the paradigm. among all the arts, music has traditionally been the medium for the purest expression of abstract structural relations. and 'rhyme', in the form of thematic variation, emerges as the fundamental principle—the stock-in-trade of nearly every musical composer. the composer presents us with, say, a simple melody, repeats it a few times and then launches into a series of variations, playing it on a different instrument, with different emphasis or in a different key, until eventually he returns to the original. but repetition of the same theme, albeit with variations, becomes in the long run relatively dull. as in poetry—as in every other 'taxonomic' activity—contrast is needed to bring home the unity of the rhyming elements, and the composer typically introduces a contrasting theme with its own variations. thus we get in a simple piece such as a chopin nocturne the following structure: two n k humphrey distinct themes, i and ii, arranged in the following way: i i ii i ii i. taking the nocturne in e flat as an example, the first tune is repeated twice so that the main key and the main subject matter may be well established in the memory of the hearer. then comes the second tune which is in the most nearly related key (so that the effect of the contrast is not lost because of too great dissimilarity). then the two tunes alternate, while at each repetition small changes are introduced, in the form for instance of decorative arabesques in the righthand part. in more complex pieces, such as beethoven sonatas, we get the composer introducing a 'development' section where the motifs of the first theme are picked up and rearranged until just at the point where the hearer may be in danger of losing track of what is going on order is restored by the 'recapitulation' of the first theme pure and simple. 'sonata form' is to my mind a perfect example of an instructive and challenging exercise in classification. if i were an educational psychologist concerned with developing teaching machines for use in schools i would not, as the american behaviourists have done, base my machines on principles derived from experiments on how pigeons perform in skinner boxes, but instead would turn directly to the hallowed principles of musical design. and that brings me close to the end of my paper—but to an end, i should say, which is not altogether in tune with the beginning. i began by saying that man-made beauty is a lie. and so, in a sense, i believe it is. it was not for the sake of beethoven sonatas that men evolved to take such a delight in classifying; to that extent, beethoven merely capitalised on a human faculty which was developed for quite other reasons. but though it may be true that, at one level, we gain nothing of biological value from learning to classify the themes of a sonata, it does not necessarily follow that listening to a sonata has no function at all. for it can be argued that, at another level, through the experience of beauty in works of art we learn to learn. i implied as much just now when i suggested that psychologists might use music as a model for the design of teaching machines. if psychologists could learn from music how best to present evidence of the relations between things in a way that people will find easy to take in, it is equally possible that laymen might learn to do it for themselves. in that way the work of art would achieve a new importance, as a model of the way we should structure our experience wherever and whenever we need to acquire genuinely useful information. everyone has heard the argument that a training in latin and greek, however irrelevant to real life, is an excellent 'training for the mind'. how much better for that purpose might be a training in the appreciation of beauty, if, as i've argued, our love of beauty has a hundred million years of educational psychology behind it. let me finish then on a more positive note. beauty may be an 'illusion'. but, for all that, keats was not so wrong in his claim that "beauty is truth, truth beauty". that may not be "all ye know on earth, and all ye need to know", but it is at least a good beginning. references bateson, p. p. g., , "internal influences on early learning in birds", in constraints on learning, eds r.a.hinde and j.stevenson-hinde (academic press, london), pp. - . bell, c, , art (chatto and windus, london). empson, w., , seven types of ambiguity (chatto and windus, london). hadfield, m., , the gardener's companion (dent, london). herbart, j. h., , practical philosophy. hopkins, g. m., , "on the origin of beauty: a platonic dialogue", in g.m.hopkins: journals and papers, edsh.house and g.storey (oxford university press, london, ). humphrey, c , , "some ideas of saussure applied to buryat magical drawings", in social anthropology and language, ed. e.ardener (tavistock publications, london), pp. - . the illusion of beauty humphrey, n. k., mcmanus, c , , "status and the left cheek", new scientist, , - . kagan, j., , "attention and psychological change in the young child", science, , - . levi-strauss, c , , structural anthropology (basic books, new york). mclelland, d. c , atkinson, j. w., clark, r. a., lowell, e. l., , the achievement motive (appleton-century, new york). pahlen, k., , music of the world; a history (spring books, london). pavlov, i. p., , "the reflex of purpose", in lectures on conditioned reflexes, voll (lawrence and wishart, london). reid, t., , essays on the intellectual powers of man. whitehead, a. n., , an enquiry concerning the principles of natural knowledge (cambridge university press, cambridge). wilbur, r., , "poetry and the landscape", in the new landscape in art and science, ed. g.kepes (paul theobald, chicago), pp. - . comm-fenyvesi.indd notices of the ams volume , number mathematical aesthetics in a beautiful town: bridges coimbra interdisciplinary discussions on the relations be- tween mathematics and the arts, science, aesthet- ics, and artistic practice have a long history. at the present time, various cultural phenomena under the influence of mathematics and the arts continue to inspire people working in different fields of sci- ence. similarly, several artists and scholars share a common interest in combining creative thinking, intellectual curiosity, and aesthetic sensibility in their work and research. the bridges conferences (http://www.bridgesmathart.org), founded and lead by reza sarhangi (towson university) and running annually since , aim to initiate a dialogue between the mathematical and the artistic points of view in various fields where artistic and mathematical thinking and practice merge. unique components of the bridges conferences, in addi- tion to formal presentations, are gallery displays of visual art; hands-on workshops designed for professional educators as well as for families and children; working sessions with artists and math- ematicians who are crossing the mathematics- arts boundaries; mathematical poetry readings; and musical, th;atrical, and movie events in the evenings. coimbra: the city of sciences, arts, and bridges the bridges conference, codirected by penousal machado, was held at the university of coimbra, portugal, during july – , . the university of coimbra was established in as the first university in portugal and the first por- tuguese language university in the world. after the much larger metropolitan areas of lisbon and porto, coimbra is the most important urban focal point of the central part of the country. it is situ- ated on the rio mondego, the longest river located exclusively in portugal. the river, which flows through the city, provides a scenic setting for the town, which invites all to walk along its river banks and across its four bridges. it was a beautiful set- ting for the bridges conference! math goes fashion since last year when bridges visited hungary, the conference has grown again and set new records. the conference received almost paper, art- work, and proposal submissions, more than ever before, presenting intriguing ideas in mathematics, in the arts, and in several other cultural domains. this year the keynote paper was coauthored by fields medalist william p. thurston (cornell university) and was presented by kelly delp (buf- falo state college). the spectacular presentation described a process that was inspired by modern fashion design and that can be adapted to con- struct many different surfaces out of paper and craft foam. another plenary paper was presented by paulus gerdes, the president of isgem, the international study group on ethnomathematics and vice presi- dent of southern africa in the african academy of sciences. gerdes analyzed instances of math- ematical ideas interwoven in the artistic decoration of handbags, hats, mats, and other products of basketry from several regions of mozambique. he shared instructive stories about “field encounters” with local handcrafters and touched upon such exciting phenomena as the tradition of geometrical kristóf fenyvesi kristóf fenyvesi is a researcher in the art and culture studies department at jyväskylä university, finland; cu- rator-in-chief of the ars geometrica international confer- ence series, pécs, hungary, which hosted the bridges world conference in ; leader of the experience workshop math-art movement; art curator of the ars geometrica math-art gallery (eger college, hungary); and coordina- tor of community events of the bridges organization. his email address is fenyvesi.kristof@gmail.com. doi: http://dx.doi.org/ . /noti paul gailiunas, bridges pécs , notices of the american mathematical society , no. (february ), – . http://www.bridgesmathart.org may notices of the ams imagination and the cultural role of the so-called “mental geometry” and their links to the future of mathematics education in africa. among the many memorable presentations, it is also important to mention the joint paper by art- ist jim r. paulsen and reza sarhangi on paulsen’s impressive sculptures sentinels. as an addition to the keynote talks, george w. hart, a member of the bridges board of directors and the chief of content at the museum of mathematics (momath) in new york city, offered exclusive insight for the confer- ence participants into momath’s most interesting innovations of interactive presentation techniques of mathematical contents in the museum. the local organizers also realized a portuguese math/art day, which featured invited talks by manuel arala chaves (university of porto, a mem- ber of the directing board of the atractor project- interactive mathematics), paulus gerdes, and joão paulo xavier (university of porto), complemented by workshops on the symmetry of plane patterns, on roman architecture in portugal, and on lunda art, inspired by sona geometry from angola. mathematics is art an exhibition of mathematical art has been an annual feature of bridges since , and it has grown steadily over the years under the dedicated leadership of robert fathauer. this year, work was submitted by more than seventy artists from twenty countries. diverse artistic media were represented, including wood, metal, and stone sculptures; beadwork; fabric; and a variety of two- dimensional media. mathematical ideas at play in the art exhibition encompassed tilings, fractals, polyhedra, hyperbolic geometry, anamorphosis, knots, topology, and magic squares. on the threshold of the digital age, it was a great pleasure to see the acrylic, watercolor, pigment, and oil paintings of aurora, anita chowdry, and jános saxon-szász at the exhibition. the process of creation and the pure sensation of the color, just like the materiality of the medium, play a central role in their art: “i do not use a calculator in order to create these paintings; i use my mind to do the math. the value of this process is that, as the painting is completed, i embody these patterns and concepts and carry them within myself.” so writes aurora in her artist’s statement. chowdry’s techniques are based on her research into the methods and materials of painting and illuminat- ing in indian and persian manuscripts. browsing among the great variety of d art- works, the visitors could play with xavier de clip- peleir’s tricky transforming bodies and admire nicholas durnan’s carved alabaster sculptures (a möbius and two variations on the theme of bor- romean rings) and bente simonsen’s beautifully mirroring steel objects. they could also study the magical skillfulness of woodcarving by bjarne jespersen. from the exhibited photographs of nick sayers’s artworks, we could also get a taste of using mathematics in contemporary conceptual “bricolage-art”. unlike much mathematical art that is purely abstract, sayers uses recognizable household ob- jects to create work that is accessible, real, and fun. the largest work he presented, as a photograph, at the exhibit was show home: a four-meter-in- diameter, three-meter-high geodesic shelter built from estate agent (realtor) “for sale” and “to let” boards. the piece made a statement about homelessness, the housing market, and sustain- able architecture. nick sayers: show home, . nicholas durnan: borromean rings , x x mm, english alabaster, . bjarne jespersen, woodcarving magic. how to transfer a single block of wood into impossible shapes, east pe- tersburg, pa: fox chapel publishing, . notices of the ams volume , number after seeing the pieces of mike naylor’s geo- metric body art, the audience could be convinced about the naked truth of the artist’s simple state- ment: “mathematics is part of us, and we are part of mathematics.” moving away from the mathematically obsessed nude people towards the dressed ones, we could enjoy remarkable ex- amples of mathematically inspired fashion design by jasmin schaitl and eunsuk hur. by the fusion of mathematics and fashion schaitl’s model shapes and defines the body in a new context and opens up a variety of exciting design processes. hur’s modular textile pieces also encourage the end user to participate in the design process by allowing the user freedom to personalize the design through playful experimentation. computer-generated graphics and animation art were also represented on a high-quality level. mingjang chen used the structural cloning method (scm) and the leaping iterated function system (lifs) to explore abstract and landscape paintings. gary greenfield’s transport network overlay se- ries are based on simulations that are inspired by mathematical models of physical and biological processes. mehrdad garousi used mandelbulb d for adventurous explorations into his extended, three-dimensional fractal worlds. daniela rinaudo, in a philosophical piece called geometric man, used computer animation to offer a virtual journey for the spectator into “imaginary time” in search of another dimension into space. nathan selikoff experimented with chaotic attractors. carlo séquin (university of california, berkeley), a plenary speaker, who together with reza sarhangi, took a major role in the organization of the scientific program of the conference, exhibited his d art- works. he also exhibited his computer graphics to visually support his plenary talk, the “tori-story”. his presentation elaborated on the classification of all topological tori into four regular homotopy classes, where the members in one class cannot be smoothly transformed into members of another class. his art submissions depicted some intriguing structures that topologically are torus surfaces but with enough surprising contortions so that most people would not immediately see them as your everyday donut. we saw innovative approaches in uniting frac- tals and tessellation art by robert fathauer, through the combination of traditional art forms like photography with digital techniques to create tree-like and knotted spiral designs that have an intriguing blend of complexity and beauty. design works are always in high favor at the bridges exhibits, especially when broadly celebrated designers like fabien vienne from france bring the honor of their presence to the exhibition. vienne’s beautiful creations convey the notion that geometry is no mere tool of composi- tion; it’s an epistemology. each of his works seeks to employ the principle of economy to find the essential in a problem and to then “substantiate” it in a least action solution, which brings that es- sence to light and to life. mathematics is culture in , for the second time in the bridges’ history, the music night was organized by dmitri tymoc- zko, a composer and music theorist at princeton university. coimbra’s professional orchestra, the orquestra clássica do centro, had graciously agreed to play mathematically inspired and inspir- ing works, both new and old. the concert featured a newly composed piano concerto by dmitri ty- moczko based on the idea of cellular automata, a recent piece by giovanni albini based on the idea mike naylor: pentamen, ” x ”, digital print, . carlo séquin: the world of wild and wonderful tori, ” x ”, composite of computer images, . c a rl o h . s éq u in , u n iv er si ty o f c a li fo rn ia , b er k el ey . may notices of the ams of symmetry, and an older piece by tom johnson in which a mathematics theorem is proved before one’s very ears! maestro artur pinho’s orchestra performed magnificently. the theater night was orchestrated by steve abbott (middlebury college), a researcher of the intersections of mathematics and theater and the coeditor of math horizons. the performance focused on a single dramatic piece: the physicists, by friedrich dürrenmatt, performed in the form of a staged reading by the conference participants themselves. a rapidly growing number of artists and educa- tors are using movies, videos, and animations for applications spanning education, industry, and the arts. the bridges math/art short movie festival, which was directed by amy christie and nathan selikoff, screened many short movies, including a virtual reenactment of escher’s drawing hands, a demonstration of the bubble-sort algorithm via hungarian folk dance, and an animation, the adventures of the klein bottle, by konstantin weix- elbaum and ilkay sakalli, supervised by konrad polthier (free university, berlin). poetry day was a new addition this year to the bridges conference. this event was coordinated by sarah glaz, a mathematics professor from the university of connecticut and a poet. there was a reading of poems with strong links to mathemat- ics. reading their own poems were emily grosholz, joanne growney, amy uyematsu, and sarah glaz. saeed ghahramani (a mathematician and the dean of arts and sciences at western new england uni- versity) read translated modern iranian poems. coimbra university mathematician and translator francisco craveiro was joined by other poets for a bilingual reading of mathematical poems that he translated into portuguese. craveiro read the portuguese translations, while the other poets read the english originals. the event ended with an “open microphone” period in which bridges participants could share their own mathematical poems with the audience. mathematics is fun mathematics can be scientific, and it can be artis- tic as well. but can mathematics be playful? can it be fun? we gave it a try at bridges family day (http://www.familyday.hu). the participating children, parents, and all the visitors had the pos- sibility, during the workshops, to test themselves as math-fashion designers with the leadership of the enthusiastic artist team of ruth mateus-berr from the university of applied arts in vienna; or as mathematical sculptors with nicholas durnan; or as weavers or quilters with elaine krayenke el- lison. we made geometry with our own bodies at the human geometry workshop led by mike naylor and vi hart; enjoyed the miracle of kaleidoscopes with curtis palmer; practiced mathematical ori- gami with wojtek burczyk; learned some tricks from a real mathe-magician, fernando blasco; played amazing puzzles with the internationally renowned designer jean-marc castera; took a quick tour in the “vasarely playhouse” with slavik jablan; played with the giant triangles of simon morgan and jacqueline sack; worked with clay under the direction of jouko koskinen; immersed ourselves in the secrets of islamic mosaic design with sarah abdellahi and tom goris; and tried the zometool mehrdad garousi: space shelter, ” x ”, digital print, . jasmin schaitl: body-index-cloth iii, x x cm, fashion, percent cotton with satin ribbon, . a b o v e: © a rt p ie ce : j a sm in s ch a it l; p h o to : j a sm in s ch a it l a n d d eb o ra d ä u b l. http://www.familyday.hu notices of the ams volume , number modeling kit with paul hildebrandt, mike strana- han, and samuel verbiese. the zometool modeling kit was in use during the conference in the castro machado museum of coimbra to build up the ambitious pentigloo: an incredible construction of , parts with a diameter of almost nineteen feet by fabien vienne, the noted -year-old de- signer who was present and worked together with the construction team (led by paul hildebrandt and jim hausman) during the construction process. such a rich and mosaic-like event, which brought participants from more than thirty countries in the world, could not be put together by just a few of- ficial chair persons. in addition to the bridges program committee of about forty individuals and the organizers of the many events described above, i should mention the important roles of the orga- nizing team in coimbra, including ana almeida from the department of physics and mathematics, isec-instituto superior de engenharia de coimbra; amílcar cardoso, the president of the centre for informatics and systems, university of coimbra, portugal; and penousal machado from the depart- ment of computer science, university of coimbra, portugal. the next bridges event will take place on july – , , at towson university, located in the baltimore metropolitan area, maryland, usa. please find more information at http://www. bridgesmathart.org/bridges- . the zometool pentigloo construction team at work. derek vorthman (left), lászló vörös (left, back- ground), scott vorthman (middle), george w. hart (right), kelly delp (right, foreground). (photo by samuel verbiese.) above: bridges around the clock: fabien vienne’s penti- gloo at day and at night in the museu nacional de mach- ado de castro, coimbra. 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: : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ zurich open repository and archive university of zurich main library strickhofstrasse ch- zurich www.zora.uzh.ch year: tableaux vivants, early cinema, and ‹beauty-as-attraction› wiegand, daniel abstract: this article offers a case study in intermediality and explores relationships between tableaux vivants performances and early cinema around . it locates processes of intermedial exchange not only at the level of form but also at the level of modes of address and reception. more speci cally, the study is concerned with how bourgeois notions of beauty were transferred to the lm image and reconciled with the attraction value of cinema. as a discussion of early lm theory reveals, the concept of “beauty in lm” depended on a taming of lmic motion, something that had already been realized in performance practices of tableaux vivants. in the subsequent analysis of the cultural context of tableaux vivants in european variety theatres, i outline a speci c mode of address, which i term “beauty- as-attraction:” an overlap of the older aesthetics of the beautiful and the more modern aesthetics of attraction. through concluding lm analysis, i show how tableaux vivants became a model and source of inspiration for early cinema, thus bringing to fruition the two-fold address of beauty-as- attraction in a new media context. doi: https://doi.org/ . /ausfm- - posted at the zurich open repository and archive, university of zurich zora url: https://doi.org/ . /uzh- journal article published version the following work is licensed under a creative commons: attribution-noncommercial-noderivs . unported (cc by-nc-nd . ) license. originally published at: wiegand, daniel ( ). tableaux vivants, early cinema, and ‹beauty-as-attraction›. acta universitatis sapientia. film and media studies, ( ): - . doi: https://doi.org/ . /ausfm- - https://doi.org/ . /ausfm- - https://doi.org/ . /uzh- http://creativecommons.org/licenses/by-nc-nd/ . / http://creativecommons.org/licenses/by-nc-nd/ . / http://creativecommons.org/licenses/by-nc-nd/ . / https://doi.org/ . /ausfm- - tableaux vivants, early cinema, and beauty-as-attraction daniel wiegand university of zurich (switzerland) e-mail: daniel.wiegand@fiwi.uzh.ch abstract. this article offers a case study in intermediality and explores relationships between tableaux vivants performances and early cinema around . it locates processes of intermedial exchange not only at the level of form but also at the level of modes of address and reception. more specifically, the study is concerned with how bourgeois notions of beauty were transferred to the film image and reconciled with the attraction value of cinema. as a discussion of early film theory reveals, the concept of “beauty in film” depended on a taming of filmic motion, something that had already been realized in performance practices of tableaux vivants. in the subsequent analysis of the cultural context of tableaux vivants in european variety theatres, i outline a specific mode of address, which i term “beauty- as-attraction:” an overlap of the older aesthetics of the beautiful and the more modern aesthetics of attraction. through concluding film analysis, i show how tableaux vivants became a model and source of inspiration for early cinema, thus bringing to fruition the two-fold address of beauty-as- attraction in a new media context. keywords: early cinema, intermediality, film theory, art, painting. “living photographs are about as far from being things of beauty as anything possibly could be.” cecil hepworth ( , quoted in bottomore , .) film pioneer cecil hepworth’s harsh judgment (quoted in the motto) notwithstanding, many of the earliest films and film programmes strove to attain painterly effects and were advertised as especially artistic and beautiful. examples include the scenic views of waterfalls and sea waves by the american mutoscope and biograph company (see musser )‚ the many filmed versions of famous a longer version of this article was published in german in film bild kunst: visuelle Ästhetik des vorklassischen stummfilms, ed. jörg schweinitz and daniel wiegand. marburg: schüren, (zürcher filmstudien ). i would like to thank the series editors for permission to publish a shortened version in english. acta univ. sapientiae, film and media studies, ( ) – doi: . /ausfm- - daniel wiegand paintings by producers such as lumière, pathé, and gaumont (see robert ), and the screenings by female itinerant exhibitor “mme olinka,” advertised as “living watercolour photographs of the highest artistic value.” these artistic tendencies came to the fore around , when international film companies increasingly catered to highbrow audiences and intellectuals began to write about film as a valid cultural expression. in germany in particular, writers like georg melcher, hermann häfker, and herbert tannenbaum discussed the art value of film and devised ideas for artistic film programmes, partly modelled on the notion of richard wagner’s gesamtkunstwerk. many of these discussions revolved around ideas of film as “painting in motion” and as an expression of beauty. beauty was a key concept of bourgeois culture at the time, especially in the german bildungsbürgertum. the ideas associated with it were largely derived from an everyday understanding of classical idealist aesthetics and neo-platonic thought that circulated in popular books and magazines. they implied the equation of beauty and art, the association of the beautiful with the true and the good (at the time often capitalized in english), and an emphasis on harmony and perfect proportions. these conceptions were often modelled on the classical art of antiquity, including its afterlife in neoclassicism and contemporary art, as taught and practiced at the big art academies. although these ideas and preferences contradicted more recent trends in philosophical aesthetics and the emerging art movements of modernity, they nevertheless profoundly shaped the cultural life of the bourgeoisie and its interaction with mass culture. thus, attempts to adapt beauty as a valid category for the new medium of film were inherently contradictory. as previous research has abundantly shown, many early films were indebted to the aesthetics of attraction rather than to the aesthetics of classical art. in many instances, films aimed less at contemplative perception than at the satisfaction of schaulust, that is, of sensation-seeking visual curiosity (see e.g. gunning and ; schwartz ). according to tom gunning, early cinema’s “aesthetic of attraction” was, in fact, almost an “anti-aesthetic” ( , ) in terms of traditional notions of art reception. der artist vol. ( ), n.p. some of these authors’ texts have been translated into english in kaes/baer/cowan . for texts in german see schweinitz and diederichs . while this article discusses international film production, the theoretical discourse examined is largely german. among other things, the titles of popular middle-class periodicals such as die schönheit (beauty) and schönheitskult (cult of beauty) or events like the “schönheit- abende” (beauty nights) in berlin (see runge , – ) point to the significance of the notion of beauty in turn-of-the-century germany. for an opposing, and equally justified point of view on early cinema see musser . tableaux vivants, early cinema, and beauty-as-attraction in the present essay, i examine the arguments, aesthetic choices, and reception strategies that were necessary in order to connect the cinematic image to conventionally bourgeois notions of beauty. as i will show, the idea of the “beautiful film image” in the early th century resulted from a complex interplay of theoretical discourses, stylistic practices, and novel audience expectations. specifically, i argue that the aesthetics of motion in early film images had the capacity to contradict common notions of beauty and was therefore often tamed or domesticated – both in theory and in cinematic practice – in order to pave the way for the “beautiful film image” as a theoretical concept and creative product. this domestication was not a mere process of suppression. in fact, i argue that a number of films from around used a specific mode of address, which emphasized what i call “beauty-as-attraction.” this was an amalgamation of the aesthetics of the beautiful (associated with traditional art forms such as painting and sculpture) and the aesthetics of attraction (which characterized much of the era’s popular visual culture). my claim is that this mode of address had existed before – and continued to exist – in variety theatre, and more specifically in the performance tradition of tableaux vivants, which thus served as a model and source of inspiration for these early films. the present article is thus concerned with issues of intermediality, locating the interaction between classical art forms, early film, and tableaux vivants at the level of specific modes of address and reception. arrested motion: domesticating the moving image in early film theory the first cinematographic projections presented a new aesthetics of motion, which was also advertised as such by exhibitors. the german travelling cinema ohr, for instance, called attention to its film screenings through a comparison with other moving-image devices in : “what a difference between these primitive machines [referring to the zoetrope and the electrotachyscope] and the cinematograph! the extraordinary progress in the field of photography has made it possible for this machine to capture everything that plays out in front of the camera in the smallest conceivable partial motions.” the passage suggests that the projected film image does not just transform individual bodies or clearly delineated objects into pronounced movements; rather, it sets everything in for a similar perspective on these processes of adaptation see curtis ( ). programme booklet of the ohr travelling cinema, , nördlingen city archives (call number e iv , ). daniel wiegand motion. this alludes to an aesthetics of motion such as can be observed in many of the lumières’ early outdoor scenes, which show bathing people, arriving locomotives, or lively street traffic. these images seem to pulsate below the surface, so to speak, as if they were composed of a multitude of synchronous and interpenetrating micro-motions. to many contemporaries, the “life stirring thousandfold” in early film footage did not appear as the result of deliberate artistic creation, but as a merely technical reproduction of an external reality. as early as , british journalist o. w. winter thus wrote: “here, then, is life; life it must be because a machine knows not how to invent; but life which you may only contemplate through a mechanical medium” ( , ). this impression of “life,” a trope in many comments of the time which would eventually lead to the notion of film as a “living picture,” does not refer to a gentle animation emanating from within (as suggested by the latin anima, which means soul, or breath). rather, it means a technically reproduced exterior motion that is beyond the grasp of the human mind. as winter writes: “we cannot follow the shadows in their enthusiasm of recognition” ( , ). as it seemingly evaded any artistic shaping, cinematic motion offered an entry point for the unplanned, the unpredictable, and the contingent in the eyes of contemporaries (see doane , ). in this regard, film was a visual manifestation of a loss of control, because it opened up the image – hitherto almost invariably seen as the result of an immobilizing human act of creation – to life, a life that, in modernity, was increasingly conceived of as constantly changing, contingent, mechanically induced, and therefore not fully controllable. this new cinematic aesthetics of motion held a great fascination for many spectators and could thus also be employed in advertising. at the same time, it was obviously hard to reconcile with the traditional – and still dominant – bourgeois notion of beauty, which was inextricably linked to ideas of the meaningful and spiritual. while classical aesthetics did include the beauty of movement in the concept of grace, this referred to “willful movements […] which express moral sentiment,” that is, a meaningful emotional expression ultimately radiating from within (schiller , – ). but contingency as a visual effect, insistently explicit distinctions between the cinematograph and other moving image devices are common at the time. in , for example, uruguayan luis gonzaga urbina speaks of a “liveliness that the kinetoscope lacks” ( , ). see also gunning . report on a film screening with footage of geman navy league boats, in nördlinger anzeigenblatt ( march ), . while doane conceives of contingency as a consequence of cinematic temporality primarily at the narrative level, it seems equally important to me to view it as a visual effect stemming from the mechanical reproduction of numerous small motions that are only minimally purposeful, if at all. tableaux vivants, early cinema, and beauty-as-attraction asserting itself in the motion dynamics of early films, was diametrically opposed to the idea of the artist whose organizing hand creates beauty by consciously shaping reality. beauty as an expression of meaning and order rather than of coincidence was still a theoretical premise of neo-kantian thought in the early th century, as emphasized by georg simmel in a essay on kant: “art […] organizes existence, until it displays the summariness, the inherent necessity, the suspension from the burden of coincidence, […] insofar as the art work lets this form resonate into a subjective feeling, it also contains beauty” (simmel , ). as cinema became a part of visual culture that could no longer be ignored, it began to challenge the cultural leading role of fine art, especially in germany. for a bourgeois audience that saw itself as a representative of this art sphere, film images must have seemed deeply unsettling. of course, this also had to do with the fundamentally plebeian character associated with the new mass medium, with its sensationalist and supposedly vulgarizing subject matter that appealed to the “lower instincts.” yet, it was not least the motion of the images that constituted a provocation for an aesthetic sensibility schooled in contemplative art viewing. often, commentators such as max bruns and konrad lange detected nothing but “horrible confusion” and “restlessness and blurriness” (schweinitz , ; lange , ). nevertheless, reactions to the new “cultural factor” of cinema were quite diverse, even among the middle classes. whereas a decidedly hostile attitude initially dominated in germany, the s saw the emergence of aesthetic concepts for a cinematic volkskunst (popular art) that would be acceptable to bourgeois culture (see schweinitz , ). efforts of this kind were concentrated in the so-called kinoreformbewegung (cinema reform movement), which sought to integrate cinema into the ranks of bourgeois cultural assets, and thus attacked the allegedly corrupting forms of popular film. this is also where the notion of beauty entered the scene, assuming the role of a virtual combat term against “immorality,” “filth,” and “tripe.” thus, cinema reformer hermann häfker claimed a “right to beauty” for the film-going public, “a right of the people and of youth […] to be protected from ugly impressions that are offensive to the senses and damaging to health” ( ). this pedagogical impetus, here linked to the notion of beauty, was widespread in germany. karl wilhelm wolf-czapek, for instance, wrote in his monograph die kinematographie: wesen, entstehung und ziele des lebenden bildes: “in the big catalogues, and sometimes also at screenings, one sees images of the kind that should be cultivated, capable of eliciting instruction, a pleasure in beauty, and the formation of taste” ( , ). however, to credibly reframe the film image as a signifier of beauty required daniel wiegand a fundamentally different concept of cinematic motion, for which a potential aesthetic value had yet to be claimed. a comment by georg kleibömer from is symptomatic of this need for reinterpretation: “will the image really cease to be poetic, will it not become even more poetic when the whole image is set into motion, especially for those who are unaccustomed to the contemplation of artworks and lack imagination? […] to my view it would indeed be possible to judge a moving image according to artistic principles like composition or execution” (kleibömer ). reconciling cinematic motion with the laws of beauty demanded a normative aesthetics, which avoided the particularly disturbing forms of movement causing “horrible confusion,” while emphasizing and welcoming others that were more easily adapted to traditional aesthetic concepts such as the composition mentioned by kleibömer (see wiegand b). around , various authors thus began to conceive of the film image as “painting in motion.” that is, while they recognized motion as a constitutive element of cinematic imagery, they conceptually related it to the stasis of painting, with all its attendant formal qualities and reception categories. in this regard, cinematic motion was no longer the disturbing other, inevitably opposed to the artistically composed picture, but rather its gentle expansion. this expansion was not allowed to stray too far from painterly compositions, though, so that the static image and its status as the highest realization of artistic standards remained ultimately untouched. accordingly, some writers in the german cinema debate called for more participation of fine artists and suggested bringing to life their paintings in film. as gustav taudien suggests: “let us have all the events that preceded the single moment captured by the painter actually play out before our eyes, with the famous picture by the respective painter as the worthy finale” ( ). in sum, the emerging film-theoretical discourse transferred the aesthetic category of beauty to the mass-cultural phenomenon of film by systematically distinguishing “good” and “bad” kinds of cinematic motion, thereby conceptually subjecting it to a tendency towards stasis. structurally, these authors demanded something that had already been realized practically in previous years, namely in the static and beautiful displays of tableaux vivants. in early film history, the idea of “realizing” paintings in films is frequently expressed and also put into practice (see robert ). on the german debate about the involvement of painters in film production see diederichs , – . tableaux vivants, early cinema, and beauty-as-attraction arrested beauty: tableaux vivants in variety theatre when calling for more cinematic beauty, wolf-czapek compares cinema’s role in society to that of the established institution of variety theatre, which is “to be a stage for physical beauty and physical strength, for colour- and light-suffused joyous art” ( , ). the author thus draws on a bourgeois discourse of reform that began in the late th century with the emergence of the big variety stages – which addressed a highbrow bourgeois audience – and explicitly applies this discourse to the incipient efforts to reform cinema. the older debate, conducted primarily in the german variety trade press, was still current at the outset of the new reform movement aimed at cinema, and it included several authors who also wrote about film (e.g. oscar geller and a. günsberg). like the cinema reformers, the variety reformers were concerned with elevating forms of entertainment that originated among and addressed the lower classes – such as circus shows – in order to lend them a semblance of art for middle-class audiences. with growing economic dominance, the middle classes had become increasingly interested in popular culture during the late th century, while simultaneously looking for ways to dissociate themselves from forms of “low,” seemingly plebeian entertainment. they were thus open to adapting the respective phenomena to fit their own understanding of art and beauty (see maase , – ). accordingly, the efforts of german variety reformers to designate circus acts as art became condensed in the notion of “beauty” and in the core idea of an “increasingly perfected aesthetics” (günsberg ). like the later debate on cinema, this discussion often focused on visual aspects. in variety theatre, this primarily concerned the performers’ shapely bodies, their elegant movements, and the design of the stage with the help of lighting and décor. the purported link to the traditional arts was supposed to manifest itself in the aesthetic qualities of the performances as well as in the increasingly splendid architecture of the variety palaces. in the course of these efforts, no other kind of act was mentioned as often and as unquestioningly as that of tableaux vivants, that is, “the representation of works of painting and sculpture by living persons” (brockhaus , ). in addition to animal acts, songs, comedy, and various circus acts, tableaux vivants were a staple in the diverse repertoire of the variety stages, and they remained hugely popular well into the th century. tableaux vivants were presented either by individual performers [fig. ], by small groups of two to four [fig. ], or by larger ensembles; in the latter case they usually operated under the name of the artistic daniel wiegand director, presenting spectacular “mass pictures” (massenbilder). sometimes, they re-enacted paintings – with painted backgrounds and a picture frame to create a surface impression –, sometimes freestanding sculptures. for reformers such as a. günsberg, the “aesthetic aspect” ( ) that should be a mark of all variety acts found its most complete expression in tableaux vivants. they offered a convincing argument for variety theatre as a site of art and beauty because their origins were not in travelling circus shows, but in highbrow theatre and in the aristocratic and upper-middle-class salons of the late th and early th centuries. integrated into a sophisticated culture of parlour games and theatricals (which also included charades and masquerades), they were aimed at the acquisition of “good taste” and the constitution of an educated elite, with the re-enacted images belonging to an authoritative canon of art history, which the performers literally incorporated (see jooss ). even when tableaux vivants became a widespread attraction of popular culture over the course of the th century – appearing on fairgrounds, in circuses, and in light theatre – they never fully shed their connotations of the artistic, contemplative, and sophisticated. one reason for this was their subject matter: even in these popular contexts, the tableaux re-enacted paintings and sculptures from the sphere of classical, neoclassicist, and contemporary academic art. henry de vry’s gallery of living pictures, for example, performed at berlin’s wintergarten in , presented works of then-current representatives of the german and french art academies such as hermann von kaulbach and Émile bayard in addition to neoclassicist sculptures and the venus de milo. the names of the fine artists were printed on the playbill, which shows how explicitly a popular attraction adorned itself with the insignia and prestige of “true” art in order to address an educated and art-oriented audience familiar with these names and titles, thus giving them an incentive to see the show. even when tableaux vivants didn’t represent specific works – so-called free compositions became increasingly popular in the early th century – they were stylistically informed by the artistic taste prescribed by the academies, which pervaded bourgeois cultural life. the similarities can be seen when comparing a work re-enacted by de vry in – glaube, liebe, hoffnung (faith, love, hope) by austrian court painter josef arpad koppay – with the photograph of a tableau vivant by de vry that had no specific model: both consist of a frontal – or at least unhindered – view of shapely bodies seen in their entirety, clearly standing out against a simply designed background in a balanced overall composition. [figs. – .] playbill of the berlin wintergarten theatre, berlin city museum. tableaux vivants, early cinema, and beauty-as-attraction furthermore, tableaux vivants were especially suited to draw on notions of beauty from classical aesthetics because – like paintings and sculptures – they presented static images. although the variety reformers also tried to develop conceptions of beauty for more movement-oriented performances by describing their “harmoniousness of movement” and “artistic elegance” (kurz-elsheim ; see also lasker ), the completely arrested bodies of tableaux vivants offered a conceptual reference point of artistic contemplation in which ideas of the aesthetic image culminated, as it were. thus, even when they didn’t adopt specific motifs, tableaux vivants lent themselves to established conventions of picture composition and art contemplation more easily than other types of popular performance. advertisements accordingly emphasized the “grace of lines and of the composition in general” and the “pleasure of graceful lines.” the arresting of living bodies into static images, constitutive of tableaux vivants, can be seen as an emphatic display of the aesthetic aspect in variety theatre and as a radical capture of the potentially ugly performing body. as if to emphasize this point, british journalist w. t. stead described pansy montague’s popular tableaux vivants as a kind of immobilized island of beauty amid an otherwise crudely grotesque programme: “each tableau formed an exceedingly beautiful picture, upon which the eye, fatigued with the endless procession of grotesque and ugly and garish figures, dwelt restfully and lovingly. it was a glimpse of the clear blue sky, or of the midnight heaven radiant with stars” (stead ). tableaux vivants as an “attractional dispositif” and beauty-as-attraction although tableaux vivants pointedly referenced the tradition of art and the aesthetic canon of bourgeois culture, they were simultaneously a visual attraction appealing to the schaulust of an urban and potentially multi-class mass audience. in this regard, they followed the same dynamics of novelty and spectacle as any other kind of variety act. they were advertised as an “unparalleled box- office draw” and “first-rate attraction.” as i argue more thoroughly elsewhere (wiegand and a), the attraction consisted in the display of well-shaped (often scantily-clad or naked) bodies, and in impressive body control, which allowed for the near-complete illusion of lifelessness. furthermore, tableaux leipziger general-anzeiger, quoted from an advertisement for the mimiplastika pygmalion gallery, in das programm ( ), n.p.; advertisement for henry de vry, in das programm vol. ( ), n.p. daniel wiegand vivants constituted an astonishing and decidedly modern technology of image production. along with serpentine dances, illuminated water fountains, and screen projections (such as magic lanterns and films), they belonged to the so- called dark acts (dunkelnummern), for which the auditorium lights were dimmed to show off special light effects (de vry ). starting around , this included – inherently modern – electric lights. to use an apt term by frank kessler (which he employs in relation to early cinema), the tableaux vivants of the variety stages thus functioned as an “attractional dispositif” ( ). the technical apparatus and the viewing situation in which the pictures were presented made them visual attractions. the darkening of the auditorium, the lighting of the stage, and possibly also the suspense created by the opening curtain served to focus the spectators’ attention and captivate their gaze. even the lighting was an attraction in itself while simultaneously transforming the bodies on stage into a potentially dematerialized image to be looked at (see faulk , – ). thus, at the intersection of sensational light design and aesthetic picture composition, tableaux vivants addressed their audience both with the lure of the latest attraction and with the promise of beauty, art, and sophistication. the result was a kind of overlap between the aesthetics of attraction and classical aesthetics at three different levels – the rhetorical-discursive level, the level of picture composition, and the level of reception. at the rhetorical-discursive level, advertisements in variety periodicals alternately emphasized the sensational aspect and the artistic value of the numbers. often, these two rhetorical strategies were interlaced, as in a promotional text for the group les olympias [fig. ]: “until now, these poses have only been presented in white (marble) or gold (bronze). as a novelty, les olympias bring vivid poses in patina (old bronze). the green hue of antique bronze has a soothing effect on the eye, does not blind it and – making the poses stand out ever more vividly – offers the viewers true artistic pleasure.” what is announced as a sensational novelty is simultaneously meant to enable artistic pleasure. the introduction of the new hue is thus the logical consequence of a sensationalist consumer culture always aiming for novelty, but also the result of a competent aesthetic judgment, intended for contemplation. in terms of picture composition, many of the paintings that typically served as models for tableaux vivants already contained a certain attraction potential – with bodies frontally presenting themselves to the viewer’s gaze – which readily lent itself to the stage context. at the same time, the paintings’ emphasis on advertisement in das programm vol. ( ), n.p.; original emphasis. tableaux vivants, early cinema, and beauty-as-attraction compositional harmony and balance in the distribution of lines, surfaces, and colours corresponded to classical aesthetics. by imitating such art works, tableaux vivants preserved their qualities, but also modelled them into components of an “attractional dispositif” through immediate physical display and spectacular lighting effects. finally, the overlap described above constitutes a phenomenon of reception. the cited advertisement assumes an audience equally interested in spectacular variety attractions and in art, indeed, an audience for whom the elaborate presentation of the most recent art works itself is an attraction. similarly, the playbill for de vry’s gallery of living pictures implies an audience familiar with the bourgeois cultural technique of art contemplation (thus the mention of painting titles and artist names), while also marvelling at the modern “lighting effects and the apparatus with which the images are transformed.” for the type of spectator addressed, then, a desire for art appreciation and an appetite for new visual sensations pervaded each other. i propose the term “beauty-as-attraction” to describe this specific mode of address, which pitched tableaux vivants as spectacular attractions and simultaneously pointed to their beauty and their connection to the traditional arts. in terms of reception, this mode can be linked to a certain schaulust, albeit of a tamed kind that was less about erotic allure, violence, or thrill, and more about the visual enjoyment of colours, lights, and shapes. these elements were designed so as to constantly surprise and overwhelm the sense of vision (in the vein of an attraction), while simultaneously relating to classical aesthetics, a traditional iconographic repertoire, and established categories of art reception. beauty-as-attraction in film film drew on the performance practices of tableaux vivants early on, thus transferring beauty-as-attraction to a new media context. among the earliest examples are several series of productions by the american mutoscope and biograph company, either made or re-released in new compilations between and . [fig. .] the biograph picture catalog highlighted these films separately within the genre label of vaudeville views and linked them to the this phrase from de vry’s playbill possibly refers to a revolving stage mechanism. in his article cinema and visual pleasure (kino und schaulust), later dadaist walter serner disdainfully wrote about the “thickly powdered and besmeared nude bodies” ( , ) of tableaux vivants as an example of what he termed the “harmless variety” of schaulust ( , ) as opposed to the true and cruel schaulust in cinema ( , ). daniel wiegand idea of an artistic refinement of the film image: “we call particular attention to our series of living pictures which were put on with as great care as to models, costumes, pose and properties as any of the largest productions of this order. they are excellent photographically, and of the highest grade pictorially.” many of the french and german productions advertised as films artistiques or kunstfilms around also drew on the performance practices of tableaux vivants as seen on the variety stages at the time. examples include les heures and le printemps ( ), two phonoscènes by director louis feuillade, who would release a whole production series for gaumont under the title le film esthétique (the aesthetic film) only a year later. both films presented a thematically but not narratively motivated sequence of shots, showing female bodies arranged into picturesque groups with obvious references to antique art and mythology. le printemps begins by showing a field and a frozen spring; through a dissolve, the water is transformed into a spluttering spring and a woman in a white gown appears above it, lying motionless for about seven seconds like in a tableau vivant, before she slowly moves her arms and plays with the white birds fluttering around. [fig. .] soon afterwards, two children enter the scene and also start playing with the birds, while the basic image composition remains the same. all the other shots follow a similar pattern: the figures appear as if retrospectively inserted into pre- existing, static, and picturesque compositions of flowers, trees, and bodies of water, sometimes within round or oval frames; their movements are either markedly slow or dance-like. [fig. .] the film is strikingly similar to certain tableaux vivants staged by henry de vry, for instance his phantasmagorien, traumbilder (dream images), or his schäferspiel (pastoral) entitled johannisnacht. these performances also presented images of female bodies on (artificial) fields and meadows, with lighting effects that lent them a magical quality. the traumbilder were described as follows: “flocks of fluttering butterflies animate the scene, and floating groups of superbly beautiful girls ( people) conjure up the most beautiful feast for the eyes in dreamy light effects. an entire fairy world is created: mermaids, nymphs, elves, mythological goddesses, shepherdesses with a large grazing herd, partly biograph picture catalog , . it should be added that these films oscillated between the conflicting tendencies of artistic ennoblement and erotic display; see wiegand . phonoscènes were films distributed together with music recorded on sound discs. the publicity text for this series, written in the style of a manifesto, called for the “beauty of ideas and beauty of form” as guiding principles (feuillade ). to the best of my knowledge, no copy of les heures survives, but there are a number of historic publicity posters, advertisements, and programme notes (see e.g. ciné-journal no. [ ], n.p.; der kinematograph no. [ ], n.p.; die lichtbild-bühne no. [ ], die lichtbild- bühne no. [ ], n.p.). tableaux vivants, early cinema, and beauty-as-attraction in brightest sunlight, partly in moonlight never before seen in such an effect. a magically beautiful allegory crowns the ending.” le printemps and de vry’s stage performance thus share the references to mythological imagery and the interweaving of physical and natural beauty through aestheticizing light effects and colours. while de vry’s tableaux vivants employed coloured lights, films like le printemps brought the luminous appearances to the screen with the help of the projector light and coloured film stock. in , Émile cohl also made some films for gaumont using tableaux vivants. l’éventail animé begins with a screen-filling frontal view of a folded fan, which soon opens up as if by magic. through a dissolve, women appear on the individual fan leaves, each holding another fan in their hands. [fig. .] while the film shows the magical coming-to-life of a fan by way of cinematic tricks, the focus seems to be more on the resulting splendorous ornamentation of the image: the symmetrical composition of female poses presents itself to the audience’s gaze for several seconds without further changes through additional tricks. accordingly, the american publicity for the film by the george kleine optical company points out the impression of beauty evoked by the fan: “a delightfully pleasing and beautifully hand-colored series of panoramic views […]. a large ostrich feather fan opens alternately showing each time a different scene.” ornamental “living fans” were a common type of tableaux-vivants act on variety stages. in , tableaux-vivants director dr. angelo appeared at berlin’s wintergarten theatre with the number der lebende fächer in watteau manier (the living fan in the manner of watteau), and in addition to the main attraction, he also showed “wonderful living porcelain imitations in the style of sèvres and meißen, majolica reliefs, and other creations in the field of mechanics.” [fig. .] in l’éventail animé, the living fan is the prelude to a series of six short scenes, which illustrate the use of fans in well-known historic situations. [fig. .] by framing the individual shots with the contours of a giant fan (similar to the circles and ovals in le printemps), the ornamentation from the first shot is carried over into the rest of the film. at the same time, the frame marks a proscenium and thus introduces another level of representation, making the figures seem as if arranged on a stage rather than appearing in a film. even if they don’t keep completely still, the staging of the scenes is obviously reminiscent of tableaux vom berufsleben, in das organ vol. ( ), . unfortunately, the surviving copy of the film does not contain the original colouring. moving picture world vol. / ( ), . in the th century, fans with motifs by french painter jean-antoine watteau were popular. moderne kunst (monthly edition) xix/ ( / ), . daniel wiegand vivants: the conspicuous parallel staging without any background, the bodies’ mostly frontal positioning towards the viewer, the overall preservation of poses despite some movement, and finally, the limited dramatic development and reduction to specific representative moments. the film’s serial structure, with individual episodes exemplifying the same basic idea (in this case, the fan as a historic leitmotif) also resembles the performance structure of many tableaux vivants. l’éventail animé almost ideally fulfils what authors such as wolf-czapek demanded for film at the time, namely “the clear side-by-side of persons and objects,” the “avoidance of hasty movement,” and “that the figures be clearly delineated against the background everywhere in the image” ( , n.p.). in other films, the figures are in a complete standstill, at least for a while. porcelaines tendres (Émile cohl, ) consists of four shots, each presenting a short dance number. before each dance, the performers stand still for several seconds, while imitating decorative objects that contain porcelain figurines. such imitations were extremely popular on the variety stages in (see hellwig ). in the first shot entitled la coupe grecque (greek bowl), two performers form the bowl’s ornamented shaft, with the lower and upper parts represented by painted decorations. the bowl, frontally and centrally positioned, is enclosed by an adorned frame, producing an overall impression of a symmetrically arranged ornament. [fig. .] the neat composition and the dark background, against which the individual elements clearly stand out, create an impression of pictorial coherence and unity. after about ten seconds of complete stasis, the bowl is slowly lifted before the two dancers gradually start moving, climbing down from their pedestal, yet without completely abandoning their poses. while one of them eventually goes into dance movement – which nevertheless resembles a series of pictorial moments – the other sits down on the pedestal in a completely static pose. the shot ends with the dancer also assuming a static pose next to the other performer. conclusion in many ways, tableaux-vivants performances around corresponded to popular middle-class ideas about art and the contemplation of beauty. at the same time, with their overt display of luminous and spectacular body images, they constituted an “attractional dispositif.” for the operators of the big variety theatres, they thus fulfilled two objectives simultaneously: to offer new visual sensations and to present “art” to a bourgeois audience. by transferring the performance modes and visual motifs of tableaux vivants to film, this twofold tableaux vivants, early cinema, and beauty-as-attraction address of beauty-as-attraction was brought to fruition in the new context of film screenings. like the respective live performances, films such as le printemps and porcelaines tendres presented shapely bodies frontally facing viewers, turning them into displays of visual attractions through technological transformation while nevertheless preserving a connection to fine art in terms of their composition and content. the successful shift from variety number to cinematic motif was aided by the conspicuous similarities between cinema and the staging of tableaux vivants as dark acts. in both cases, the audience’s attention was directed to a succession of potentially dematerialized and often colourful images of light. both the mode of address and the film-theoretical discourse outlined above can be read as an expression of a changing visual culture around , when the emerging mass media entered into diverse and sometimes contradictory symbiotic relationships with the established arts. within these cultural negotiations, the aspect of immobilization significantly influenced the period’s theoretical discourses and aesthetic practices as a figure of thought and creative strategy. it structured notions of beauty in film – for instance in the writings of the cinema reformers – as well as the process of image-creation in tableaux vivants (on stage and screen). it was only in the modes of stasis and near-stasis, it seems, that attempts to reconcile traditional aesthetics with the dawning of media modernity succeeded to some extent. in the films analysed here, the tendency to partially or temporarily arrest the moving image produced harmonious and well-structured compositions. this trend of immobilizing images simultaneously appeared in the emerging fiction film. certain moments in the plot become condensed into visual stops within the films’ narrative flow when hitherto mobile configurations of characters freeze for an instant, presenting orderly, memorable, and momentous compositions, which often also reference well-known paintings (see e.g. brewster and jacobs ; blom ; askari ). however, what is interesting about the films discussed here is that they do not resort to tableaux vivants within a narrative context; instead, they display stasis as a visual attraction. in addition to adopting the structural moment of arrest and the motifs from fine art, they directly reference the tableaux-vivants attractions of variety theatre. the developments outlined here are characterized by a certain ambivalence. on the one hand, they can be seen as a conservative reaction to new forms of visual media such as film, which shook the foundations of accepted aesthetic principles and hierarchies. on the other hand, as shown above, these “conservative” tendencies were inherently contradictory as they often united divergent notions of the aesthetic. thus, the discourse on film as “painting in motion” simultaneously daniel wiegand reflected the need for resorting to familiar categories of classical aesthetics and the educated middle classes’ hesitant acceptance of media modernity. in other words, classical image composition and the attractions of modern visual media overlapped in the mode of beauty-as-attraction, which was therefore especially successful in the new medium of film. rather than simply imposing an antiquated notion of beauty on the films discussed here, this mode allowed them to express a complex layering of varied and partly contradictory aesthetic ideas. however, to many advocates of art and aesthetics, films such as porcelaines tendres might very well have represented a tendency towards banalization, in the sense of reducing the artistic to something merely pretty, decorative, or even kitschy – a tendency that would occasion its own defence mechanisms over the course of film history (see galt ). many contributions to the classical film theory of the s and s – especially the writings of béla balázs and jean epstein – turned decidedly against the picturesque, decorative, stylized, and arrested elements in film, often condescendingly labelling respective scenes as tableaux vivants (see epstein , ; balázs , ). conversely, these authors emphasized the cinematic qualities that had already appeared in the earliest film discourses around , but were “suppressed” by the reformist theorists. these very qualities – elusiveness and coincidence, for example – were now being linked to the concept of beauty (see delluc , ). throughout the history of film and film theory, notions of beauty thus seem to alternately crystallize around and distance themselves from similar creative principles and theoretical ideas. beauty as a visual quality that is characteristic of static and harmoniously composed images, and which had therefore already reached its peak in painting, is one such insistently repeated topos – whether formulaically invoked in journalistic film criticism to this day or, conversely, raised as the spectre of a theoretical stance according to which the fluid and shifting character of cinematic experience is the epitome of beauty. (translated from german by susie trenka.) in pretty ( ), rosalind galt traces a continuous line from kant’s classic-idealist aesthetics to the film theory of andré bazin in the s, a connection expressed in the appreciation of the “valuable” and the corresponding devaluation of the pretty as that which is only superficially beautiful. to my mind, this needs to be qualified insofar as most of the classic film theorists did not reject the pretty or decorative in film simply because they saw themselves as defenders of idealist aesthetics and as opponents of art’s alleged trivialization. rather, they viewed the unreflecting appropriation of fine art by film overall as an illegitimate and doomed undertaking, because for them, it suppressed what was felt to be revolutionary and new in cinematic aesthetics (expressed in terms such as delluc’s photogénie). tableaux vivants, early cinema, and beauty-as-attraction references askari, kaveh. . making movies into art: picture craft from the magic lantern to early hollywood. london: palgrave macmillan. balázs, béla. 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[ ]. life is a game according to a set of rules. in in the kingdom of shadows: a companion to early cinema, eds. colin harding and simon popple, – . london: cygnus arts press. wolf-czapek, karl wilhelm. . die kinematographie: wesen, entstehung und ziele des lebenden bildes [the cinema: essence, origins and goals of the living picture]. dresden: union deutsche verlagsgesellschaft. wolf-czapek, karl wilhelm. . ueber den stil des kunstfilms [on the style of the artistic movie]. der kinematograph no. : n.p. tableaux vivants, early cinema, and beauty-as-attraction list of figures figure . undated photograph of tableaux vivants performer kitty (and dog); courtesy of stadtmuseum berlin (reproduction: friedhelm hoffmann, berlin). figure . full page advertisement for the tableaux vivants group olympier in das programm no. ( ); courtesy of stadtmuseum berlin (reproduction: friedhelm hoffmann, berlin). figure . josef arpad koppay: glaube, liebe, hoffnung ( ), reproduction for a picture postcard. figure . detail of a picture postcard with a tableau vivant by henry de vry (c. ). daniel wiegand figure . by the sea, from the compilation living pictures (american mutoscope and biograph company, usa ); courtesy of library of congress. figures – . le printemps (louis feuillade, f , © gaumont). tableaux vivants, early cinema, and beauty-as-attraction figure . l’Éventail animé (Émile cohl, f , © gaumont). daniel wiegand figure . picture of dr. angelo’s living fan. moderne kunst (monthly edition) xix/ , / : . figure . l’Éventail animé (Émile cohl, f. , © gaumont), figure . porcelaines tendres (Émile cohl, f. , © gaumont). microsoft word - copertina - .docx the great beauty: public subsidies in the italian movie industry gianpiero meloni dimitri paolini manuela pulina w o r k in g p a p e r s / c o n t r i b u t i d i r i c e r c a c r e n o s c e n t r o r i c e r c h e e c o n o m i c h e n o r d s u d ( c r e n o s ) u n i v e r s i t À d i c a g l i a r i u n i v e r s i t À d i s a s s a r i c r e n o s w a s s e t u p i n w i t h t h e p u r p o s e o f o r g a n i s i n g t h e j o i n t r e s e a r c h e f f o r t o f e c o n o m i s t s f r o m t h e t w o s a r d i n i a n u n i v e r s i t i e s ( c a g l i a r i a n d s a s s a r i ) i n v e s t i g a t i n g d u a l i s m a t t h e i n t e r n a t i o n a l a n d r e g i o n a l l e v e l . c r e n o s ’ p r i m a r y a i m i s t o i m p r o v e k n o w l e d g e o n t h e e c o n o m i c g a p b e t w e e n a r e a s a n d t o p r o v i d e u s e f u l i n f o r m a t i o n f o r p o l i c y i n t e r v e n t i o n . p a r t i c u l a r a t t e n t i o n i s p a i d t o t h e r o l e o f i n s t i t u t i o n s , t e c h n o l o g i c a l p r o g r e s s a n d d i f f u s i o n o f i n n o v a t i o n i n t h e p r o c e s s o f c o n v e r g e n c e o r d i v e r g e n c e b e t w e e n e c o n o m i c a r e a s . t o c a r r y o u t i t s r e s e a r c h , c r e n o s c o l l a b o r a t e s w i t h r e s e a r c h c e n t r e s a n d u n i v e r s i t i e s a t b o t h n a t i o n a l a n d i n t e r n a t i o n a l l e v e l . t h e c e n t r e i s a l s o a c t i v e i n t h e f i e l d o f s c i e n t i f i c d i s s e m i n a t i o n , o r g a n i z i n g c o n f e r e n c e s a n d w o r k s h o p s a l o n g w i t h o t h e r a c t i v i t i e s s u c h a s s e m i n a r s a n d s u m m e r s c h o o l s . c r e n o s c r e a t e s a n d m a n a g e s s e v e r a l d a t a b a s e s o f v a r i o u s s o c i o - e c o n o m i c v a r i a b l e s o n i t a l y a n d s a r d i n i a . a t t h e l o c a l l e v e l , c r e n o s p r o m o t e s a n d p a r t i c i p a t e s t o p r o j e c t s i m p a c t i n g o n t h e m o s t r e l e v a n t i s s u e s i n t h e s a r d i n i a n e c o n o m y , s u c h a s t o u r i s m , e n v i r o n m e n t , t r a n s p o r t s a n d m a c r o e c o n o m i c f o r e c a s t s . w w w . c r e n o s . i t i n f o @ c r e n o s . i t c r e n o s – c a g l i a r i v i a s a n g i o r g i o , i - c a g l i a r i , i t a l i a t e l . + - - ; f a x + - - c r e n o s - s a s s a r i v i a t o r r e t o n d a , i - s a s s a r i , i t a l i a t e l . + - - ; f a x + - - t i t l e : t h e g r e a t b e a u t y : p u b l i c s u b s i d i e s i n t h e i t a l i a n m o v i e i n d u s t r y f i r s t e d i t i o n : j u n e the great beauty: public subsidies in the italian movie industry gianpiero meloni disea - university of sassari and crenos dimitri paolini disea - university of sassari, crenos and core manuela pulina polcoming - university of sassari and crenos abstract we examine the impact of public subsidies in the italian movie industry by considering two dimensions: quantity (box-office revenues) and quality (film festival awards). public subsidies and movie genres are employed as explana- tory variables to investigate how public intervention and genre influence movie industry performance. we find that although public funding shows an over- all negative influence on quantity and quality, there are some differences when considering public subsidies by genre. on balance, there is statistical evidence that dramas and thrillers are the genres that should be primarily financed by public agents. keywords: movie industry; public subsidies; awards; box office. jel classification: z ; c . introduction according to art. of the european treaty, ”any aid granted by a member state or through state resources in any form whatsoever which distorts or threatens to distort competition by favoring certain undertakings or the production of certain goods shall, in so far as it affects trade between member states, be incompatible with the internal market”. a notable exception is public aid for movies, which is permitted for cultural goals, that is, to promote culture and heritage conservation where such aid does not affect trading conditions and competition in the union to the extent that is contrary to the common interest. if we consider the main european countries in terms of movie production, we find that direct subsidies from government agencies are an important source of film fi- nancing. in , the governments of germany, france, italy and the uk provided financing in the amounts of . , . , . and . million euros, respectively. moreover, film productions can receive indirect subsidies in the form of tax shelters for investors, valued in at million euros for the uk, for italy, and for france . from the perspective of the public, several explanations that may support public intervention in the movie industry can be identified. first, movies can be viewed as merit goods for which there is often no demand from the public. in this respect, a subsidy may increase the revenue received but also decrease the costs for producers, who may be encouraged to become more efficient and to produce at a more socially oriented level. second, public intervention is desirable in the presence of positive externalities. movies often play an important role in aiding the educational devel- opment of schoolchildren by strengthening their critical skills and allowing them to witness dramatic historical episodes. informational and documentary movies can also be important for lifelong learning in adulthood. third, public subsidies for the movie industry are likely to enhance social and cultural benefits that range from regeneration, social inclusion and an affirmation of national identity (see also pratt, ). in this sense, evaluating public interventions in cultural products is not a simple task. the prior literature focused on movie performance by considering the box of- fice and tickets sold(see bagella and becchetti ( ), jansen ( ), and mckenzie and walls ( ), among others). however, to really understand the impact of pub- lic subsidies for movies, it is necessary to introduce variables linked to the quality of a motion picture given the cultural objectives of public intervention. bagella and becchetti’s ( ) work is one of the first and one of the few studies that investigates some critical issues within the italian movie industry over the period between and using a sample of italian films. using a gmm-hac (generalized method of moments heteroskedasticity and autocorrelation consis- see lange ( ) tent) approach, the authors find that public subsidies do not influence total admis- sions, daily revenues or per screen daily admissions. in addition, the positive and statistically significant effect of the comedy genre on total admissions shows that the decision to produce films in this genre has an independent, positive effect on box-office revenues regardless of ex ante cast and director popularity. jansen ( ) examines the case of the movie industry in germany and finds that public subsidies tend to support producers who have consistently had above-average success in their movie performance. hence, this finding stands in contrast with the author’s prior belief that public funding tends to distort producers’ incentives to make movies that match viewers’ expectations. more recently, mckenzie and walls ( ), for the case of australia, find that government subsidies have no impact on a film’s finan- cial success at the box office. moreover, several papers have estimated the impact of critical reviews and awards on movie revenues , but none of them consider these types of variables to evaluate the quality of cultural products. in this paper, we consider italian movies released in the domestic market between and . the aim is to provide an investigation of the impact of public subsi- dies on box-office revenues and to control for their possible impact on the quality of financed movies as well as for genre heterogeneity. on the one hand, a fixed effects and random effects panel data analysis is pursued to investigate the impact of public subsidies on box-office revenues. on the other hand, a panel poisson is employed to investigate to what extent public subsidies and genre influence the number of prizes won, which can be regarded as a proxy of implicit quality in the italian movie industry. in italy, legislation concerning economic and financial support by the public for var- ious forms of cultural activities, such as music and theatre, was issued with law on the april , , which represented the ”new discipline of interventions in favor of the performing arts” and % delineated the total funds to be granted to the movie industry. a further regulation on motion pictures was issued in that established that public funding could be allocated either directly to the production of a new movie or indirectly by subsiding movies or authors based on their quality as defined by a set of criteria. in addition, another type of contribution can be al- located to movie producers and authors based on box-office performance (see forte and mantovani ( ) for a more detailed discussion). the paper is organized as follows. section highlights the methodological frame- work. in section , the case study is presented, and a description of the data is provided. the empirical findings that emerge from the empirical investigation are reported in section . concluding remarks are presented in the last section. see mckenzie ( ) and chisholm et al. ( ) for a survey methodological framework the first step of the empirical investigation is based on an analysis of the box- office performance of the movie industry within the italian domestic market. the baseline specification consists of a movie’s revenue i as a function of public subsidies and genre, that is, comedy, drama, or thriller, with documentary treated as the reference category. the continuous variables are expressed in logarithm terms and are adjusted for inflation. the model is specified as follows: ln revenuei = β +β ln subsidization+β comedy +β drama+β thriller +εi ( ) where βr for r = [ , ] are the parameters of the model and εi is the error term. a standard panel data approach is followed by grouping the observations by year and comparing the results obtained from running a random and a fixed effects model. the random effects assumption is that the individual specific effects are uncorrelated with the independent variables, while the fixed effect assumption is that the individual specific effects are correlated with the independent variables. the hausman test is run to empirically discriminate between the two models. the next step in the investigation is to evaluate the impact of public financing for different types of movies, that is, to assess the iteration between genres and subsidies, with the latter expressed in logarithm and real terms. thus, the following specification is considered: ln revenuei = β + ∆ ′subsidized genresi + Γ ′non subsidized genresi + εi ( ) where subsidized genres is a vector of iteration variables between the four genres and public subsidies; non-subsidized genres is a vector of interaction dummy variables that takes the value if a movie belongs to a given genre and has not received public funding. ∆ and Γ are the parameters of the model, and ε is the error term. as for the baseline specification, panel random and fixed effects models are run, and the hausman test is used to empirically discriminate between the two approaches. once we can establish to what extent public intervention affects box-office revenues, as a further step in the investigation, the impact of public subsidies on the italian movie industry is assessed in terms of the quality of the financed movies. thus, the number of prizes won is employed as the dependent variable. this variable is a count variable; hence, a panel poisson model must be estimated, where the assumption that the variance is equal to the mean holds. as a robustness check, this hypothesis is further tested against a panel negative binomial model through a likelihood ratio test. the baseline model is specified as follows: prizesi = β + β festivalsi + β ln subsidizationi + β comedyi + β dramai + β thrilleri + εi ( ) where prizes for the ith movie are a function of participation at festivals, subsidies, if any, and genres. βr for r = [ , ] are the parameters to be estimated, and ε is an error term. as a further extension of the model, the iteration between subsidies and genres is also considered as follows: prizesi = β + β festivalsi + ∆ ′subsidized genresi + Γ′non subsidized genresi + εi ( ) where the subsidized genres and non-subsidized genres vectors are defined as in equation . ∆ e Γ are the parameters of the model, and ε is the error term. data to test the previous hypotheses, panel data for italian movies exhibited dur- ing the - period are employed. the dependent variable, as expressed in equations and , is box-office revenue (expressed in euros and adjusted for in- flation, base year ), which is obtained for each movie and genre from several sources . public subsidies, which are used as an explanatory variable, are obtained from mibact (ministero dei beni e delle attività culturali e del turismo). prizes won at film festivals, which are used as the dependent variable in equations and , are collected from www.cinemaitaliano.info. table presents descriptive statistics for the whole sample. insert table here the sample shows a strong predominance of dramas and comedies over thrillers and documentaries, with the former accounting for % of the sample and the lat- ter %. notably, of a total of movies were granted public subsidies from mibact. over the time span under analysis, the average public financing per movie was thousand euros, with a maximum of . million. when considering the sub- sample of financed movies, dramas account for % of the total public financing, while comedies account for %. this difference in the allocation of public resources can be explained by multiple factors: first, comedies are less likely to contain cultural aspects of public interest; second, as shown by bagella and becchetti ( ), italian movie viewers exhibit a strong preference for comedies; thus, box-office revenues for such movies are above the mean, and production companies are less likely to seek for public financing. for a subsample of movies, information on participation at film festivals and prizes won are available; of these movies received a public subsidy, which accounts for % of the subsidized movies sample. table and ta- ble highlight some interesting features regarding the statistical distribution of the in particular, www.imdb.com, www.boxeofficemojo.com, www.comingsoon.it variables. insert table and here on average, each movie in the subsample competed in festivals, winning . prizes. these values slightly increase for publicly financed movies to . festivals and . prizes. however, for both groups, there is a predominance of zero awards associated with a rather low median value (that is, the median is equal to for the whole subset, and the median is equal to for subsidized movies). moreover, the analysis of the percentiles shows that the distribution of the prizes is heavily skewed toward the right, which implies that only a small number of movies obtained the majority of the awards. the third column of tables and shows the ratio between prizes won and festival participation. while a simple correlation analysis of the two variables indicates strong reciprocity ( . ), the mean and median values are approximately %− %, respectively; hence, frequent participation at festivals does not automatically lead to more awards. results the hypotheses regarding the performance of the italian movie industry are based on two dimensions: quantity (i.e., box-office revenue) and quality (i.e., prizes won at film festivals). for the analysis of box-office performance, the baseline specification expresses the revenue of a movie i as a function of public subsidies, if any, and genre, that is, comedy, drama, thriller or documentary, which is treated as the reference category (see equation ). as stated in the methodological section, two separate specifications are run, that is, a panel random effects model and a panel fixed effects model. to establish which model empirically fits the data better, a hausman test is run. in this case, the calculated value of the chi-squared= . ( . ) implies that the fixed effects model under the alternative hypothesis is empirically a better specification that presents a higher level of efficiency. table presents the relevant results obtained from each of the specifications. insert table here overall, the results are rather congruent in terms of magnitude of the coefficients and in terms of sign in both the random and fixed effects specifications. the first result is that publicly subsided movies, when compared with non-subsided movies, have a negative impact on box-office revenue. furthermore, comedies appear to play a leading role in attracting demand, followed by thrillers and dramas, when com- pared with the reference category. these findings are all consistent with the results obtained by bagella and becchetti ( ), thus reinforcing the relevant role played by the comedy genre in driving the box-office performance of italian movies as well as the negative effects exerted by public intervention. as a further expansion of the investigation, the impact of public financing, if any, for different movie genres on box-office revenues is investigated, as expressed in equa- tion . once again, a panel random model and a fixed effects model are run. the hausman test implies that the fixed effects model presents a higher level of efficiency. insert table here table shows evidence of a positive and statistically significant impact of subsidies for three genres out of four. however, the magnitude of the interaction coefficients of non-financed movies is much higher, which highlights their greater impact on revenues. on the whole, financing comedies guarantees the best resource allocation, which again confirms the results of bagella and becchetti ( ). nevertheless, the preference of italian viewers for the comedy genre suggests further policy implica- tions. the empirical results in fact suggest that there should be a shift in public resource allocations toward thrillers and dramas, which are also likely to exert pos- itive externalities and to play a greater educational role. turning to the factors that influence the quality of the produced movies, equation is estimated employing a poisson specification. both the coefficients and the inci- dence rate ratios are presented. the latter measure is used to compare the incidence rates of events occurring at any given point in time or space. from the descriptive statistics, it emerges that of the financed movies participated in at least one festival (see table ). hence, by taking into account only film festival participation and prizes won, a subset of movies is considered. as a matter of interest, the poisson results are congruent with the results obtained when employing a negative binomial specification (full results are available upon request). the regression re- sults from the baseline model are presented in table . insert table here the magnitude of the incidence ratio for the festival participation variable con- firms that participation at festivals does not automatically lead to more awards. moreover, as in the previous baseline model, public subsidies show a negative and statistically significant coefficient sign, and the irr shows that prizes are expected to decrease by a factor of . when holding all other variables in the model constant. moreover, the genre with the best performance is drama; this result is coherent with the belief that quality may be better perceived in movies with an insightful and dramatic characterization. proceeding a step further into the specification, equa- tion is estimated, and the interaction variables (i.e., subsidies, non-subsidies and different genres) are included in the poisson specification. insert table here table shows that the impact of subsidies on quality for each of the genres is rather negligible when compared with non-subsidies. finally, the incidence rate ra- tios indicate that subsidized thrillers and dramas are the types of movies that lead to a relatively higher performance in terms of quality and therefore should also be also supported more by the public. moreover, we consider the possible impact of the added regulation from on box-office revenues and the quality of subsidized movies. we implement a dummy variable that takes the value for movies released two years after the introduction of the change in the law. a two-year lag is coherent with the average production time for a full-length motion picture and allows us to split the sample to consider a pre-treatment period so we can identify a possible shock in the dependent variables. however, we find that there is no statistical significance after the introduction of the reform in both box-office performance and awards granted. conclusions the primary aim of this paper has been to analyze the impact of public subsidies on the italian movie industry by employing panel data from to . in our analysis, we have considered two main indicators as dependent variables, quantity expressed by revenues and quality in terms of prizes won at film festivals. we have shown that public funding (compared with non-subsidized movies) yields a negative influence on performance and quality. this result is in line with that of bagella and becchetti ( ), yet there are some differences when considering public subsidies by genre. we show that there is evidence of a positive and statistically significant impact of subsidies for three out of four genres, although the non-financed movies have a larger effect on performance. if we consider the impact of subsidies on quality for each of the genres, we have found that publicly subsidized movies have a positive but a rather negligible impact. only thrillers and dramas have a relatively higher performance, as suggested by our analysis. in particular, our analysis suggests that public resources should be dedicated to enhancing dramas and thrillers rather than comedies. in fact, the latter genre tends to outperform the other types of movies both in terms of quantity and quality despite support from the public because it is the most preferred genre by italian consumers. references bagella m, becchetti l ( ). the determinants of motion picture box-office performance: evidence from motion pictures produced in italy, journal of cul- tural economics, , – . chisholm d.c., fernandez-blanco v., ravid s.a., wall w.d. ( ). economics of motion pictures: the state of the art, journal of cultural economics, pub- lished online: october . forte f, mantovani m ( ). on conventional sources on financing movies: the case of italy. th annual conference alma mater studiorum - univer- sity of bologna department of economics, - october. lange, a. ( ), film market trends and film funding in four selected euro- pean countries, european audiovisual observatory, council of europe, brussels. jansen c ( ) the performance of german motion pictures, profits and sub- sidies: some empirical evidence. journal of cultural economics, ( ), – . mckenzie j, walls wd ( ) australian films at the australian box-office: performance, distribution, and subsidies. journal of cultural economics, ( ), - . meloni, g. paolini, d. and tena, j.d. ( ) american beauty: an analysis of u.s. movies revenues in the global market. wp crenos, - . pratt ac ( ), cultural industries and public policy. international journal of cultural policy, ( ), - . tables table : movies’ descriptive statistics variable mean std. deviation min max whole sample subsidies (adjusted) genres drama . comedy . documentary . thriller . observations subsidized movies genres drama . comedy . documentary . thriller . festivals . . prizes . . observations data on festivals festivals . . prizes . . observations table : festivals and prizes festivals prizes win ratio smallest smallest smallest % % % % . % . largest largest largest % . % . % . % mean . . . std deviation . . . observations table : festivals and prizes – subsidized movies festivals prizes win ratio smallest smallest smallest % % % % . % . largest largest largest % . % . % . % mean . . . std deviation . . . observations table : italian movie revenues - base specification fixed effects random effects ln subsidies - . ** (- . ) - . *** (- . ) drama . ** ( . ) . ** ( . ) comedy . *** ( . ) . *** ( . ) thriller . ** ( . ) . ** ( . ) documentary (omitted) (omitted) r within . . between . . overall . . n t statistics in parentheses * p < . , ** p < . , *** p < . table : italian movie revenues - budget iteration with genres fixed effects random effects subs comedy . ** ( . ) . * ( . ) nosubs comedy . ** ( . ) . ** ( . ) subs drama . * ( . ) . * ( . ) nosubs drama . * ( . ) . * ( . ) subs thriller . * ( . ) . * ( . ) nosubs thriller . * ( . ) . * ( . ) subs documentary . ( . ) . ( . ) nosubs documentary . * ( . ) . * ( . ) r within . . between . . overall . . n t statistics in parentheses * p < . , ** p < . , *** p < . table : poisson model for prizes coefficients incidence ratio festivals . *** ( . ) . ln subsidies - . *** (- . ) . comedy . *** ( . ) . drama . *** ( . ) . thriller . *** ( . ) . documentary (omitted) n pseudo r . t statistics in parentheses * p < . , ** p < . , *** p < . table : poisson model for prizes - budget iteration with genres coefficients incidence ratio festivals . *** ( . ) . nosubs comedy . * ( . ) . subs comedy . * ( . ) . nosubs drama . ** ( . ) . subs drama . * ( . ) . nosubs thriller . ( . ) . subs thriller . ** ( . ) . nosubs documentary . ( . ) . subs documentary . ( . ) . n pseudo r . t statistics in parentheses * p < . , ** p < . , *** p < . ultimi contributi di ricerca crenos i paper sono disponibili in: uhttp://www.crenos.itu / e l i a s c a r r o n i , b e r a r d i n o c e s i , d i m i t r i p a o l i n i , “ p e e r g r o u p , d i s t a n c e a n d t u i t i o n f e e s : w h e n w i d e n i n g u n i v e r s i t y p a r t i c i p a t i o n i s s t i l l b e t t e r ” / b i a n c a b i a g i , m a r i a g a b r i e l a l a d u , “ p r o d u c t i v i t y a n d e m p l o y m e n t d y n a m i c s : n e w e v i d e n c e f r o m i t a l i a n r e g i o n s ” / l u c a d e b e n e d i c t i s , a n n a m a r i a p i n n a , “ i s l a n d s a s ‘ b a d g e o g r a p h y ’ . i n s u l a r i t y , c o n n e c t e d n e s s , t r a d e c o s t s a n d t r a d e ” / massimo del gatto, carlo s. mastinu, “geography, cultural remoteness and economic development: a regional analysis of the economic consequences of insularity” / m a l i k a h a m a d i , a n d r é a s h e i n e n , “ f i r m p e r f o r m a n c e w h e n o w n e r s h i p i s v e r y c o n c e n t r a t e d : e v i d e n c e f r o m a s e m i p a r a m e t r i c p a n e l ” / g e r a r d o m a r l e t t o , f r a n c e s c a m a m e l i , e l e o n o r a p i e r a l i c e , “ t o p - d o w n a n d b o t t o m - u p . t e s t i n g a m i x e d a p p r o a c h t o t h e g e n e r a t i o n o f p r i o r i t i e s f o r s u s t a i n a b l e u r b a n m o b i l i t y ” / f a b i o c e r i n a , l u c a g . d e i d d a , “ r e w a r d f r o m p u b l i c o f f i c e a n d s e l e c t i o n o f p o l i t i c i a n s b y p a r t i e s ” / r o b e r t a m e l i s , a l e s s a n d r o t r u d d a , “ m i x e d p e n s i o n s y s t e m s s u s t a i n a b i l i t y ” / g e r a r d o m a r l e t t o , “ s o c i o - t e c h n i c a l d y n a m i c s a n d p o l i t i c a l i n s t i t u t i o n s : a m u l t i l e v e l d a r w i n i a n f r a m e w o r k o f s u s t a i n a b i l i t y t r a n s i t i o n s ” / a n d r e a p i n n a , “ s h a l l w e k e e p e a r l y d i e r s a l i v e ? ” / g i a n p i e r o m e l o n i , d i m i n t r i p a o l i n i , j u a n d e d i o s t e n a , “ a m e r i c a n b e a u t y : a n a n a l y s i s o f u . s . m o v i e s r e v e n u e s i n t h e g l o b a l m a r k e t ” / s i l v i a b a l i a , r i n a l d o b r a u , e m a n u e l a m a r r o c u , “ f r e e p a t i e n t m o b i l i t y i s n o t a f r e e l u n c h . l e s s o n s f r o m a d e c e n t r a l i s e d n h s ” / g e r a r d o m a r l e t t o , “ a d e l i b e r a t i v e - p a r t i c i p a t i v e p r o c e d u r e f o r s u s t a i n a b l e u r b a n m o b i l i t y – f i n d i n g s f r o m a t e s t i n b a r i ( i t a l y ) ” / m a n u e l a d e i d d a , “ i n s u l a r i t y a n d e c o n o m i c d e v e l o p m e n t : a s u r v e y ” / e d o a r d o o t r a n t o , m a s s i m o m u c c i a r d i , p i e t r o b e r t u c c e l l i , “ s p a t i a l e f f e c t s i n d y n a m i c c o n d i t i o n a l c o r r e l a t i o n s ” / f r a n c e s c o q u a t r a r o , s t e f a n o u s a i , “ a r e k n o w l e d g e f l o w s a l l a l i k e ? e v i d e n c e f r o m e u r o p e a n r e g i o n s ” / a n g e l o a n t o c i , f a b i o s a b a t i n i , m a u r o s o d i n i , “ o n l i n e a n d o f f l i n e s o c i a l p a r t i c i p a t i o n a n d s o c i a l p o v e r t y t r a p s . c a n s o c i a l n e t w o r k s s a v e h u m a n r e l a t i o n s ? ” / a n n a b u s s u , c l a u d i o d e t o t t o , “ t h e b i - d i r e c t i o n a l r e l a t i o n s h i p b e t w e e n g a m b l i n g a n d a d d i c t i v e s u b s t a n c e s ” / a l e s s a n d r o f i o r i , t a d a s g u d a i t i s , “ o p t i m a l i n d i v i d u a l c h o i c e o f c o n t r i b u t i o n t o s e c o n d p i l l a r p e n s i o n s y s t e m i n l i t h u a n i a ” / o l i v i e r o a . c a r b o n i , p a o l o r u s s u , m e a s u r i n g e n v i r o n m e n t a l a n d e c o n o m i c e f f i c i e n c y i n i t a l y : a n a p p l i c a t i o n o f t h e m a l m q u i s t - d e a a n d g r e y f o r e c a s t i n g m o d e l / l u c a d e i d d a , j o s é j . c a o - a l v i r a , “ f i n a n c i a l l i b e r a l i z a t i o n a n d t h e d e v e l o p m e n t o f m i c r o c r e d i t ” www.crenos.it copertina - the great beauty - meloni paolini pulina crenos wp contributi - women fighters and the .beautiful soul. narrative women fighters and the ‘beautiful soul’ narrative laura sjoberg laura sjobergis assistant professorof politicalscience at the university of florida. abstract this article explores women’s presence in military forces around the world, looking both at women’s service as soldiers and at the gendered dimensions of their soldiering particularly, and soldiering generally. it uses the ‘beautiful soul’ narrative to describe women’s relationship with war throughout its history, and explores how this image of women’s innocence of and abstention from war has often contrasted with women’s actual experiences as soldiers and fighters. one of the great stories in the history of modern warfare is that of jeanne d’arc. with the french on the verge of losing the hundred years’ war and henry vi of england claiming rights to the french throne, teenage jeanne – inspired by the voices of saints – cut her hair, dressed in a man’s uniform, and took up arms for the french cause. after convincing the french leadership of her calling, jeanne passed the necessary examinations, and was given troops to command and a military rank as captain. jeanne d’arc led the french to their first victories over the british in memory. particularly, her victory at the battle of orleans in may of is widely considered miraculous, and credited with allowing the french to crown charles vii king of france that summer. at the coronation, jeanne was given a place of honour next to the king, and ennobled for her services. the next year, however, she was captured in battle and turned over to an ecclesiastical court, which tried her for heresy and witchcraft. much of her fourteen-month trial centred on her choice of men’s clothes over women’s clothes, with her adversaries claiming that it was a crime against god for a woman to wear men’s clothes. jeanne was convicted, and burned at the stake on may – shy of her th birthday. volume number march doi: . /s x in , a posthumous retrial determined that she was innocent of all charges, and she was named to sainthood in by pope benedict xv. part of jeanne d’arc’s story is the story of a young, courageous, divinely inspired commander who played a crucial role in saving france from british takeover, and fell too early to the politics of religion and social control. part of her story is the story of the quick shifts in political loyalty in th century france, which was devastated by disunity, religious disharmony, the plague, and the hundred years’ war. however, jeanne d’arc’s story cannot be told or understood without reference to the fact that she was a young, courageous, divinely inspired woman commander, and a woman victim of the chaos in france at the time. both her physical womanhood and gender-based expectations of jeanne d’arc’s behaviour are prominent features even in a short retelling of the story of her life. because she was a woman, jeanne d’arc had to dress in men’s clothes, and pretend to be something she was not, in order to join the military and command troops, regardless of her prowess at doing so. because she was a woman, many french people – much like the ones who tried and ultimately killed her – believed that jeanne was doing something unnatural and even sacrilegious dressing ‘as a man.’ because she was a woman, jeanne d’arc was expected to dress as a woman and act like a woman, which excluded being a soldier; and because she was a woman, jeanne d’arc’s refusal to ‘act like a woman’ served as evidence of heresy at her trial. it is tempting to discard jeanne d’arc’s story for a number of reasons. after all, some say, she was an anomaly as a female fighter, and even though it is clear that perceptions about her sex and expectations based on her gender played a large role in jeanne d’arc’s life and eventually her death, many people chalk that up to the prejudices of th century europe, pointing to substantial evidence that ‘things like that’ do not happen in the ‘civilized’ world any more. what those people do not see, and what this article is written to show, is that the centrality of gender-based expectations of women who participate in wars has not disappeared with women’s increasing visibility in those conflicts. after all, as we will see later in this contribution, jeanne d’arc was far from the only woman who had to dress like a man to be accepted into military service – such stories can be found in many modern european wars, as well as in the american civil war, the first and second world wars, and contemporary conflicts. women’s gender remains a crucial factor in their participation in militaries around the world. this article explores women’s presence in military forces around the world, looking both at women’s service as soldiers, and at the gendered dimensions of their soldiering particularly and of soldiering generally. it begins with an over- view of the use of the ‘beautiful soul’ narrative to describe women’s relationship with war throughout history, describing women’s innocence of and abstention from war. it then points out that this stereotypical narrative often contrasted with women’s actual experiences as soldiers and fighters throughout the history of warfare. it then discusses women’s contemporary involvement in the making and fighting of wars, relating those experiences to gender-based expectations of women’s behaviour (particularly the ‘beautiful soul’ narrative) and the gendered l. sjoberg – women fighters and the ‘beautiful soul’ narrative nature of warfare. it concludes with some insights, looking forward, for women’s participation in military conflict. women and wars in historical perspective feminist scholars have consistently argued that traditional narratives about the ways that politics works are both implicitly and explicitly gendered: they exclude women and values understood to be stereotypically ‘feminine.’ nancy huston first applied this observation to war and security discourses. she argued that a victori- ous story that people believe about a war is essential to legitimate that war and inspire people to fight in it, pay for it, and suffer for it. the plot includes the hero fighting the enemy in order to gain something important or meaningful, and winning despite long odds and extreme hardship. as huston explained, ‘it is no accident that whereas there are reams and reams of “heroic” verse, there is no such thing as “enemic” verse: in a war narrative, it is rare that anyone refers to himself as the enemy’. jean elshtain then identified the victorious story that states tell about wars as one about just warriors and ‘beautiful souls’. the protagonist in the narrative is the just warrior, who is a hero because he protects (his) (innocent) women and children from the evils of the enemy. he sacrifices his time, his body, his fear, and even his life for the good of life back home. as elshtain explained, just warriors go to war not to kill but to die for the cause. this story equates women with the cause men die for – the life back home. women are at once the object of the fighting and the just purpose of the war. they are ‘beautiful souls’ who are (incorrectly) pacifists because they are naı̈ve about the nature of war. the just warrior fights to protect the ‘beautiful soul’’s innocence and the quality of her life. war is therefore necessary because the world would be unthinkable without innocent women. women’s consent to those wars is not only irrelevant but actually undesirable; it would corrupt their innocence. the ‘beautiful soul’ narrative, then, sets women up as the prizes of most wars – fragile, removed from reality, and in need of the protection provided by men. the same war stories also emphasize women’s mothering, where women’s identities are crucially tied to ‘bearing and rearing children on the home front’. nancy huston, ‘tales of war and tears of women’, in women and men’s wars, judith h. stiehm (ed.), pergamon press, oxford, . ibid., p. . jean b. elshtain, ‘sovereignty, identity, sacrifice’, in millennium: journal of international studies, vol. , no. , , pp. – . georg w.f. hegel, the phenomenology of spirit, oxford university press, clarendon press, translated by a. v. miller, , p. ; jean b. elshtain, women and war, basic books, new york, ; jean b. elshtain et al., ‘just war as politics: what the gulf war told us about contemporary american life’, in but was it just? reflections on the morality of the persian gulf war, david e. decosse (ed.), doubleday, new york, , pp. – . v. spike peterson and anne s. runyan, global gender issues in the new millenium, westview press, boulder, co, , p. . volume number march ‘beautiful souls’ mother soldiers, at home and on the battlefield. they provide love and nurture, and at once serve as a support for the logistical and moral fighting for the war and as a symbol of the good and pure that requires the evil of fighting to save it. in this understanding of women’s relationships with war, there is no room for women fighting wars – they are at once fought over in war and protected from it. scholars have pointed out that the ‘beautiful soul’ narrative has played a substantial role in a number of international conflicts throughout history. chivalric narratives are woven throughout many war histories. the trojan war was fought in part over the beautiful helen. in thucydides’ famed account of the peloponnesian war, the melians’ punishment for weakness is that the men are killed, while the women and children (the spoils of war) are taken as slaves. machiavelli, in a chapter called ‘how a state is ruined because of women’ argues that the temptation of women as prizes can cause conflict. elshtain recognized the ‘beautiful soul’ in the united states’ post-world war i debates about women’s suffrage, where anti-suffragists argued that women’s participation in decisions to make war would corrupt the purity of femininity. she also pointed out that the image of women as belonging to a sphere of peace was even prevalent in world war ii, where ‘beneath her overalls, rosie [the riveter] was still “wearing her apron” in the expectation that demobilization would restore the status quo ante’. elshtain was, even initially, quite clear that the ‘beautiful soul’ narrative extended past the two world wars. she explained that: ‘it would be unwise to assume that the combined effects of vietnam, feminism, and the involvement of over per cent of adult american women in the labor force … undercut received webs of social meaning as these revolve around men, women, and war’. indeed, feminist scholars have identified elements of the ‘beautiful soul’ narrative in other, more recent wars. cynthia enloe pointed out that, ‘if there is an image that defines television’s coverage of the [first] gulf crisis, it’s a disheveled white woman coming off a boeing , an exhausted baby on her shoulder’. my own work identifies the use of the ‘beautiful soul’ narrative to describe women in both the first gulf war and the united nations security council economic sanctions regime against iraq in the s. spike peterson and anne sisson runyan identify stereotypical images of passive and protected women as being complicit in genocide and genocidal rape in the former yugoslavia. across these joshua s. goldstein, war and gender: how gender shapes the war system and vice versa, cambridge university press, cambridge, , p. . j.b. elshtain, women and war, above note , pp. , . ibid., p. . ibid., p. . cynthia enloe, the morning after: sexual politics at the end of the cold war, university of california press, berkeley, ca, , p. . laura sjoberg, gender, justice, and the wars in iraq, lexington books, lanham, md, , p. . v.s. peterson and a.s. runyan, above note , p. . l. sjoberg – women fighters and the ‘beautiful soul’ narrative different times and cultural contexts, there are variations in the specific charac- teristics of the ‘beautiful soul’ who is the subject of wars’ justificatory stories. still, from these past empirical studies, it is possible to identify unifying characteristics of the use of the ‘beautiful soul’ narrative. the ‘beautiful soul’ narrative can be recognized, first and foremost, by its emphasis on women’s difference from men: specifically, on women’s innocence and peacefulness. related to this differentiation between characteristics tradition- ally associated with femininity and characteristics traditionally associated with masculinity, the ‘beautiful soul’ narrative can also be identified by the separation of a private sphere (where women are, and naturally belong) and the sphere of war- making and war-fighting (where something has gone terribly wrong if women are included). third, the ‘beautiful soul’ narrative uses women’s femininity as a justi- fication for war and/or a reason to fight for peace. these three characteristics together can be used to find and analyse the ‘beautiful soul’ narrative in accounts of women’s roles in wars, from ancient times to present day. were women ‘beautiful souls’? even as the ‘beautiful soul’ narrative has dominated most accounts of women’s relationships with the enterprise of war, women have been (usually under the radar) soldiers, support personnel, and fighters in war throughout history. while there is hardly space for a comprehensive history of women’s involvement in warfare, substantial evidence exists that women have been a part of many major conflicts where their roles have usually gone unnoticed. women have been involved as soldiers and fighters in most of the world’s major conflicts, and, as the jeanne d’arc story that starts this article chronicles, this is not a uniquely modern phenomenon. in addition to well-known stories about women’s participation in conflict (like the stories of the amazons in greek mythology, there is evidence that women participated in and/or led many ancient conquests, including many of the battles of the shang dynasty, the biblical cam- paign in qedesh, several battles for the british throne, the defence of argos, the battle of scythia, the (alleged) rd century bc japanese invasion of korea, the siege of lacedaemon, the peloponnesian war, the battle of raphia, several struggles for control of the roman empire, and battles to eject the chinese from vietnam in the st century ad. in the middle ages, saint genevieve is credited with averting attila from paris in the th century ad. priestess hind al-hunnud led her people in a battle against muhammed. muhammed’s widow led his troops in the battle of the camel. in the th century, a woman named kahina is credited with leading the berber resistance against the umayyad conquest of north africa. also in that century, saxon women are credited with battling charlemagne in large numbers. many tales uncited stories in this section come from a number of collected sources over the years. volume number march tell of viking women’s fierceness in battle. a woman named akkadevi, an indian princess, led a siege in the battle at gokage. isabel of conches, a norman, rode armed as a knight in the th century. female chinese general liangyu played a large role in the song defeat of the jin in the th century. in the th century, indian queen rani rudrama devi led her troops into battle, and was ultimately killed fighting. queen margaret of anjou commanded troops successfully in the war of the roses. these stories of women’s participation in warfare only become more common in modern times. there was substantial participation by women fighters in the american revolution, the american civil war, the mexican revolution, world war i, the russian civil war, the spanish civil war, world war ii, the korean war, the vietnam war, the afghan civil war, the iran–iraq war, the rwandan genocide, the civil war in sierra leone, and many others. women’s consistent (and increasing) service to militaries, not only in supporting but also in combat capacities, stands in stark contrast to the dominant narrative of women as innocent of and protected from men’s wars. still, even when women’s fighting is recognized, very often it is recognized as women’s fighting instead of as fighting the same wars in the same ways as men. women’s agency in their soldiering is often doubted, and women’s violence is associated with flaws in their femininity, maternity, physiology, or sexuality. still, even accounts that blame women’s soldiering on flaws in their femininity maintain crucial elements of the traditional, inherited ‘beautiful soul’ narrative, proving that however involved women get in conflicts, they remain, to some degree, understood as the innocent elizabeth p. ellett, the women of the american revolution, charles scribner, new york, . deanne blanton and lauren m. cook, they fought like demons: women soldiers and the american civil war, louisiana state university press, baton rouge, la, . tabea a. linhard, fearless women in the mexican revolution and spanish civil war, university of missouri press, kansas city, . kimberly jensen, mobilizing minerva: american women in the first world war, university of illinois press, urbana and chicago, . w. bruce lincoln, red victory: a history of the russian civil war, – , da capo press, new york, . t.a. linhard, above note . emily yellin, our mothers’ war: american women at home and at the front during world war ii, simon and schuster, new york, . lester h. brune, the korean war: handbook of literature and research, greenwood publishing group, new york, . judith stiehm, arms and the enlisted woman, temple university press, philadelphia, pennsylvania, . elaheh rostami-povey, afghan women: identity and invasion. zed books, london, . valentine m. moghadam, modernizing women: gender and social change in the middle east, lynne rienner, boulder, co, . laura sjoberg and caron e. gentry, mothers, monsters, whores: women’s violence in global politics, zed books, london, . megan mackenzie, ‘securitization and desecuritization: female soldiers and the reconstruction of women in post-conflict sierra leone’, in security studies, vol. , issue , april , pp. – . l. sjoberg and c.e. gentry, above note ; laura sjoberg and caron e. gentry, ‘reduced to bad sex: narratives of violent women from the bible to the war on terror’, in international relations, vol. , no. , march , pp. – . l. sjoberg – women fighters and the ‘beautiful soul’ narrative outsiders in the making and fighting of wars. two examples from contemporary warfare – of women soldiers in the ‘war on terror’ and of women terrorists in the last decade – betray the remnants of the ‘beautiful soul’ narrative in the reception of women warriors. women soldiers, the ‘war on terror’ and the ‘beautiful soul’ narrative far from being relegated to history as women’s fighting becomes more common- place, the ‘beautiful soul’ narrative can be found in stories about women soldiers fighting ‘against terror’ in the ‘war on terror’. as melisa brittain explains: ‘images of white female us and uk soldiers deployed in iraq were used in the first months of the invasion as icons of female liberation to illustrate the supposed benevolence, moral superiority, and progressiveness of the west. however, at the same time that white female soldiers were held up as models of female emancipation and western benevolence, they were also presented as helpless and vulnerable in the face of the perceived threat of sexual violence on the part of arab men’. when, in fact, the largest threat of sexual violence to women soldiers in iraq came from male soldiers in their own units, the risk of rape by iraqi men (though not a single instance has yet been confirmed by a female victim) was emphasized in news media and military reports about the welfare of women soldiers in iraq. the most well-known individual story occurred early in the war, with the capture and subsequent ‘rescue’ of private jessica lynch. jessica lynch is widely thought of as the first woman prisoner of war in the united states’ invasion of iraq. she was, at the time, a nineteen-year-old white woman from west virginia, serving in a combat support unit which had been in an automobile accident in the iraqi desert. her humvee was attacked by iraqi troops, and several of the members of her unit were taken prisoner and/or killed. lynch was taken prisoner by the iraqi troops, and held for eleven days. the initial reports about what was happening to her described her as a potential victim of torture and rape at the hands of hypermasculine iraqi soldiers. melisa brittain, ‘benevolent invaders, heroic victims, and depraved villains: white femininity in media coverage of the invasion of iraq’, in (en)gendering the war on terror, krista hunt and kim rygiel (eds), ashgate, london, , pp. – . sheila jeffreys, ‘double jeopardy: women, the us military, and the war in iraq’, in women’s studies international forum, vol. , issue , , pp. – . laura sjoberg, ‘agency, militarized femininity, and enemy others’, in international feminist journal of politics, vol. , issue , , p. . shoshana johnson, an african-american woman in lynch’s unit, was captured at the same time, see above note , p. . in fact, another woman, a native american from arizona, lori piestawa, was killed in that encounter. volume number march in military and media reports, lynch was characterized as brave beyond her femininity but nevertheless limited by it, needing an elaborate, public rescue. saving private lynch was discussed both in public discourse and official military discourse in terms of the fear that her iraqi captors would sexually violate her. as brittain notes, ‘most reports of lynch’s ordeal note that she is a small-town girl from west virginia, and that her only opportunity to get a college education was to join the army’. because lynch was characterized as naı̈ve and innocent, ‘the drama of lynch’s capture was dwarfed only by the drama of her rescue’ which emphasized the violence that men had to perform in order to save their women. the theme of female soldiers’ vulnerability reaches beyond stories about jessica lynch. a number of news reports imply or explicitly argue that there are unique risks for women soldiers who require unique protection. hal bernton, in the seattle times, laments that it is more difficult to protect women soldiers ‘in the unruly realm of central iraq’, but ‘in this war, as in those that came before, the army seeks to keep female soldiers away from the front line’. nicholas kristof reported on ‘the most astoundingly modern weapon in the western arsenal’ whose ‘name was claire, and she had a machine gun in her arms and a flower in her helmet’. the fate of women soldiers (upwards of % of whom are married to male soldiers) is often discussed in terms of what happens to their children if a mother dies in combat, implying that the loss of a mother is more serious to children than the loss of a father. jessica lynch at first sight looks like a woman who is being held equal to (and even above) men. she and other female soldiers, after all, are being allowed to occupy jobs in the united states military previously reserved for men, and are being given protection from combat and from their fellow soldiers as they do so. still, gender-stereotypical images of these women run through media, military, and academic accounts of their service. even though they are soldiers, women who fight ‘against terror’ in the ‘war on terror’ for the united states are often characterized as innocent, in need of protection, and in need of rescue. the first element of the ‘beautiful soul’ narrative – that women are more peaceful than men – is evident in stories of lynch and other female soldiers in the war on terror. lynch was constantly characterized as a ‘girl’, who had joined the army to see the world and to fulfil her goal of becoming a kindergarten teacher. in describing private lynndie england, general janis karpinski characterized her as l. sjoberg, above note , p. . m. brittain, above note , p. . l. sjoberg, above note , p. . hal bernton, ‘soldiers try to suppress anguish as iraq tours are extended’, in the seattle times, january . nicholas kristof, ‘a woman’s place’, in new york times, april , available at http://edition. cnn.com/ /us/ / /nyt.kristof/ (last visited february ). nancy gibbs, ‘the private jessica lynch’, in time, november , http://www.time.com/time/ magazine/article/ , , , .html (last visited february ). m. brittain, above note , p. . janis karpinski, personal interview with author, hilton head, south carolina. october . l. sjoberg – women fighters and the ‘beautiful soul’ narrative young, weak, and naı̈ve, implying that she was vulnerable rather than violent in her participation in the prisoner abuse in iraq. as hal bernton described above, women are allowed into the united states military, but ‘protected’ from the front lines because of their vulnerability. other women soldiers are often considered persons in need of protection rather than protectors, ‘beautiful soul[s] who could not escape the mold, even with a gun and a uniform’. in the stories about american women soldiers in iraq, there is also a private sphere that they belong to separate from the sphere of war-making and war-fighting. reports about jessica lynch emphasized her (apolitical, non-violent, and traditionally feminine) reasons for joining the military, including the desire to see the world and the hope to become a kindergarten teacher. sabrina harmon, one of the women accused of prisoner abuse at abu ghraib, has been described frequently in terms of her attraction to family units in iraq, and her proclivity to help iraqi women stock their refrigerators and cook in their kitchens. many stories about the deployed female fighting force emphasize the home(front) that they left behind, expressing concern about their children’s well-being in their absence, and, much like the stories of world war ii that jean elshtain described, implying that when the war was over, they would be able to go back to the status quo ante of being mothers first and soldiers second, if at all. women soldiers’ motivations are kept out of the political or war sphere in these stories, and when women are recognized as being in that sphere, their presence is described as temporary and undesirable. the third element of the ‘beautiful soul’ narrative is that women are used as a casus belli – a reason to fight in the war. melisa brittain observes that the jessica lynch story was ‘designed to increase support for the invasion of iraq and validate the continued presence of us and uk forces’. at the time that lynch was cap- tured, the coalition forces had taken over baghdad, and there was a real question in the media whether the war was over, and a withdrawal was called for. when lynch was captured, however, attention turned to questions about and news of her potential rescue – because war is about protecting innocent women, and an innocent woman was a pow. jessica lynch’s rescue ‘involved almost a dozen helicopters and several hundred soldiers’ in order to save her ‘from a horrible death’ in a hospital that contained only lynch and the medical staff caring for her. fighting for lynch, rather than seeing her as a fighter, was key to stories about perhaps, as melisa brittain hypothesized, as a show of cultural superiority (above note ). l. sjoberg, above note , p. . l. sjoberg and c.e. gentry, above note , p. . e.g. n. gibbs, above note . j.b. elshtain, note , p. . m. brittain, above note , p. . see e.g. anthony shadid, ‘baghdad power out for first time in war’, in pittsburgh post-gazette, april , available at: http://www.post-gazette.com/world/ baghdadwp .asp (last visited february ). l. sjoberg, above note . barbara ferguson, ‘lynch rescue was a perfect operation,’ in aljazeerah.info news, april , avail- able at: http://www.aljazeerah.info/news% archives/ % news% archives/april% % news/ volume number march her – an indicator that, despite fighting in the war and being captured as a prisoner, lynch remained, in public discourse, a ‘beautiful soul’, along with her fellow female soldiers. women terrorists and the ‘beautiful soul’ narrative women who call themselves shakhidki constitute a majority of the chechen suicide bombers in the ongoing conflict between russia and chechnya. the women suicide bombers are known more commonly by the name given to them by the russian government, the ‘black widows’. though these women are not only involved with the conflict, but often leaders in it, they are characterized in political, media, and academic discourses as helpless, weak, and innocent – descriptions that eerily echo the ‘beautiful soul’ narrative. for example, one account explains that ‘when a chechen woman’s hus- band is killed, she can’t marry again … she has to put on a black mourning dress for the rest of her life. but by dying, she gets closer to her beloved. that’s why the women were so scary. they had no reason to live’. another characterization of one of the women who held hostages at the moscow theatre in seems to ignore her participation in violence and focus on her femininity. the woman is described as ‘very normal’, courteous, and as someone who would ‘ask people about their children’ and ‘always say, “everything will be fine. it will finish peace- fully”’. the maternal element of the women terrorists’ motivations is also em- phasized in many accounts, which portray the women as avenging the deaths of their husbands or (especially) their sons. another element in discussions of the ‘black widows’ is that they often portray the women suicide bombers as incapable of making their own choices to participate in terrorism and war. groskop describes the ‘black widows’ as ‘pawns in a man’s game’, denying that they have any agency in their choice to fight in the war. most stories describe the shakhidki as raped, drugged, or blackmailed into suicide missions. other narratives are careful to distinguish real or normal % news/lynch% rescue% was% a% perfect% operation% aljazeerah.info.htm (last visited february ); l. sjoberg, above note . anne speckhard and khapta akhmedova, ‘black widows: the chechen female suicide terrorists’, in y. schweitzer, female suicide bombers: dying for equality?, jaffee center for strategic studies, tel aviv, , pp. – . n.p. walsh, ‘sisters in arms’, in the guardian, september , p. . mark macdonald, ‘“black widows” remain mysterious one year after moscow theater siege’, in knight ridder/tribune news service, october . viv groskop, ‘women at the heart of the terror cells’, in the guardian, september , available at: http://www.guardian.co.uk/chechnya/story/ , , .html (last visited february ). a. speckhard and k. akhmedova, above note , p. . in their extensive empirical study of chechen women suicide bombers, speckhard and akhmedova found no evidence of this style of coercion. they explained that ‘we find strong evidence of self- recruitment and strong willingness to martyr oneself on behalf of one’s country’ (above note , p. ). see also viv groskop, ‘chechnya’s deadly black widows’, in the new statesman, september ; n.p. walsh, above note , p. ; s.l. myers, ‘young, female, and carrying a bomb’, in the international l. sjoberg – women fighters and the ‘beautiful soul’ narrative women from women who participate in terror, who are ‘fanatical’, ‘warped’, ‘mad beasts’. the russian government has (effectively) used the purported victimiza- tion of chechen women suicide terrorists to its political advantage in the conflict. during the first war for chechen independence, ‘russian and chechen women together vocalized objections to the fighting, vilifying the military and pointing out that the most frequent victims of the conflict were simple soldiers and innocent civilians’. the russian government, however, has been able to break up this alliance effectively by portraying the chechens as monsters for drugging and selling (their) women into suicide terrorism. partly as a result of these characterizations, russian popular support for the second conflict in chechnya has been substantially higher. in the middle east, very different women in very different conflicts find themselves portrayed in very similar ways. women make up around % of palestinian suicide bombers, and less than % of suicide bombers in iraq. women in the palestinian resistance movement are often characterized as being manipu- lated either by family members or family tragedy into joining the movement. as mia bloom observed, female suicide bombers in palestine are often ‘portrayed as the chaste wives and mothers of the revolution’. she explains that wafa idris (the first palestinian woman suicide bomber) was characterized in one newspaper as a ‘bride of heaven’, while another described her bombing in terms of the virgin mary, ‘from mary’s womb issued a child who eliminated oppression, while the body of wafa became shrapnel that eliminated despair and aroused hope’. middle eastern women’s dependence on men has also been a theme of discussions about their motivations for committing suicide terrorism. divorce, herald tribune, august ; bridget conley, ‘for the women of chechnya, hope dies last’, in journal of human rights, vol. , no. , september , p. . l. sjoberg and c.e. gentry, above note , p. . ian bruce, ‘special force has unenviable record’, in the herald, september . owen matthews, ‘so warped by hate, they will kill anyone to take revenge against russia’, in the daily mail, september , p. . l. sjoberg and c.e. gentry, above note , p. ; galina eremitcheva and elena zdravomyslova, ‘die bewegung der soldatenmütter – eine zivilgesellschaftliche initiative. der fall st petersburg’, in martina ritter (ed), zivilgesellschaft und gender-politik in russland, campus verlag, frankfurt am main, , p. . maya eichler, ‘a gendered analysis of the chechen wars’, in international feminist journal of politics, vol. , no. , december , pp. – ; peter baker, ‘“new stage” of fear for chechen women’, in washington post, october , p. a , available at http://www.washingtonpost.com/ac /wp-dyn/ a - oct ?language=printer (last visited february ). l. sjoberg and c.e. gentry, above note , p. . julie peteet, gender in crisis: women and the palestinian resistance movement, columbia university press, new york, , p. ; karla j. cunningham, ‘cross-regional trends in female terrorism’, in studies in conflict and terrorism, vol. , no. , , p. . mia bloom, dying to kill: the allure of suicide terror, columbia university press, new york, , p. . ibid., pp. – . barbara victor, an army of roses: inside the world of palestinian women suicide bombers, rodale press, new york, , p. . volume number march loss of family members, adultery, and motherhood have all been popular explanations for women’s participation in suicide terrorism in palestine and iraq. in fact, ‘the language of domesticity and motherhood are particularly strong regarding palestinian and al qaeda female suicide terrorists’. stories about women who commit suicide terrorism in the middle east also deny women’s agency in their violent actions and separate violent women from ‘real’ or ‘normal’ women. the women have been characterized as ‘twisted, horrible women’ who let down their families by engaging in actual violence rather than supporting the violence of their men. they are told of as monstrous, warped, and having lost their connection to normal or real women and femininity. that women engage in self-martyrdom has been a rallying cry in each conflict, especially in the israeli-palestinian case. for example, opponents of the palestinian cause have published statements like: ‘what kind of men use women to hide behind…?’, and ‘almost certainly, the palestinian terrorist organizations will continue to take advantage of the innocent appearance of women to carry out terrorist attacks’, proving there are no limits to the palestinians’ tactics. on the other hand, from the palestinian side of the conflict, the fact that innocent women need to participate in suicide terrorism shows just how hopeless and unjust the situation of palestinians is. one would expect that stories of women suicide bombers would be the last place that the ‘beautiful soul’ narrative could be found. after all, women suicide bombers appear to be the opposite of the peaceful, innocent, and withdrawn women that the ‘beautiful soul’ narrative centres on – they are the threat from which ‘innocent’ civilians need protection, rather than the people in need of pro- tection. still, despite the participation of these women in a particularly brutal sort of conflict, all three elements of the ‘beautiful soul’ narrative can be detected in media and academic depictions of their behaviour. first, the stories of women michael rubin, ‘who is responsible for the taliban’, in middle east review of international affairs, vol. , no. , march . claudia brunner, ‘female suicide bombers – male suicide bombing? looking for gender in reporting the suicide bombings of the israeli-palestinian conflict’, in global society, vol. , no. , , p. . tery toles patkin, ‘explosive baggage: female palestinian suicide bombers and the rhetoric of emotion’, in women and language, vol. , no. , , pp. – ; stephen farrell, ‘grandmother blows herself up in gaza’, in the times online, november , available at: http://www. timesonline.co.uk/tol/news/world/middle_east/article .ece (last visited february ). l. sjoberg and c.e. gentry, above note , p. . s. farrell, above note . l. sjoberg and c.e. gentry, above note . quotes respectively taken from: ‘female palestinian homicide bomber’, in jihadi du jour, november , available at: http://jihadidujour.blogspot.com/ / /female-palestinian-homicide-bomber.html (last visited february ); israeli ministry of foreign affairs, the exploitation of palestinian women for terrorism, april , available at: http://www.mfa.gov.il/mfa/mfaarchive/ _ / / / the% exploitation% of% palestinian% women% for% terroris (last visited february ). tim mcgirk, ‘palestinian moms becoming martyrs’, in time, may , available at: http://www. time.com/time/magazine/article/ , , , .html (last visited february ). l. sjoberg and c.e. gentry, above note , p. . l. sjoberg – women fighters and the ‘beautiful soul’ narrative suicide bombers emphasize women’s peacefulness in a number of ways: by distin- guishing violent women from normal women, by denying women’s agency in their violence, by emphasizing the importance of mothering by female suicide bombers, and by (in the chechen case) the characterization of even willing female terrorists as more peaceful and humane than men. second, we can see the separation of the private sphere (where women belong) and the sphere of war in several facets of these stories. many stories isolate the private sphere (husbands, children, and/or personal honour) as women’s motivation to self-martyr, rather than any actual involvement in the sphere of war and/or the politics of the conflict. these characterizations are often accompanied by the strong implication that there is a clear separation between crazy women (who would martyr themselves) and real or normal women (who remain pure ‘beautiful souls’). in addition, stories that support women suicide bombers often mourn that the conflict has become so bad that women must leave the private sphere in order to participate in the conflict, implying (as elshtain pointed out above) that the just result of the conflict would allow women to return to their peaceful, innocent, and naı̈ve lives at home. finally, many stories that oppose women’s self-martyrdom frame the ‘use’ of a woman as a suicide bomber as being of particular horror, because women’s proper role remains in the private sphere. the third element of the ‘beautiful soul’ narrative is the appropriation of ‘beautiful souls’ as a reason to fight in the conflict. as noted above, the russian government uses the alleged use and abuse of chechen women suicide bombers as a call to arms. similarly, those on the israeli side of the conflict with palestinians often measure the barbarity of their enemy by what they ‘do to’ (their) women in terms of allowing (and allegedly forcing) them to participate in suicide terrorism. despite their (as the empirical evidence suggests, often willing) decision to explode themselves in an effort to kill others, women suicide bombers are often portrayed in a similar light to the ‘beautiful souls’ that elshtain and even hegel identify from tens or even hundreds of years ago – as innocent, naı̈ve, fragile, at home in the private sphere, and worth fighting to defend. women soldiers in the st century as women become more integrated into state militaries and non-state fighting forces, significant barriers to their ‘equal’ participation remain. as i have men- tioned before, women do not join military organizations that have suddenly be- come gender-neutral in response to their presence. instead, women join military groups with decades, maybe even hundreds of years, of history as masculinized organizations guided by men and values associated with masculinity. throughout history, women participating in wars have had to hide their femininity by dressing like men, meet the physical standards of manliness along with the social standards l. sjoberg, above note . volume number march of femininity, and deal with other double standards and stereotypical under- standings of women’s capacities and ‘proper place’. feminist theorists have repeatedly identified the ‘beautiful soul’ narrative as a fundamental part of discourses justifying the making and fighting of wars. though feminist scholars have identified the ‘beautiful soul’ narrative as present in most (if not all) modern conflicts, it has been suggested that the changing nature of warfare, along with women’s increasing participation in conflicts (as part of state militaries, as well as in non-state revolutionary forces and terrorist groups) would be likely to diminish the prevalence of the ‘beautiful soul’ narrative. it seems logical, then, that narratives of just citizen-warriors defending passive ‘beautiful souls’ would dissipate in the wake of the disappearance of state-centric wars and the active roles that women are playing in contemporary warfare. this article, however, has demonstrated that many uses of the ‘beautiful soul’ narrative to describe women who commit military or terrorist violence skew or ignore observable patterns in women’s behaviour. women who engage in vio- lence, are politically active, and frequent the public sphere are described in terms that frame them as innocent, withdrawn, peaceful, apolitical, and without agency in their choices. the consistency of this narrative even as women’s roles in war-making and war-fighting resonate with it less has two possible explanations: first, it could be residue from decades, and even centuries, of the perception that women were the pure, innocent victims of war who need protection from it; second, it could be that there is something that fundamentally links the ‘beautiful soul’ narrative and the justification of modern warfare. while the first explanation probably has some influence, this article suggests that it is fruitful to consider the possibility of the second, in order to understand both the meaning of war and the meaning of gender in global politics. earlier in this article, we discussed nancy huston’s argument that a victorious narrative about a war is key to a belligerent’s ability to justify the war and rally the resources and troops needed to fight it. jean elshtain then contended that each belligerent’s victorious narrative about war included a story about brave, just (masculine) citizen-warriors rescuing or protecting pure, innocent (feminine) ‘beautiful souls’. if, as huston argues, a victorious narrative has been key to the practice of all war, and as elshtain argues, in practice, these victorious narratives j.b. elshtain, above note , p. . laura sjoberg, ‘the gendered realities of the immunity principle: why gender analysis needs feminism’, in international studies quarterly, vol. , no. , p. . l. sjoberg and c.e. gentry, above note , p. . this is not to say that women are not still disproportionately affected by war; quite the contrary, most of war’s humanitarian effects, in the short and long term, still affect women differently (and often more severely) than men. it is only to argue two things: first, there is no trade-off between victimhood and agency; second, women do not now and have not ever fitted into the neat mould that the ‘beautiful soul’ narrative frames for them. n. huston, above note . j.b. elshtain, above note . l. sjoberg – women fighters and the ‘beautiful soul’ narrative have relied on differentiated gender roles to sustain them, then the practice of war itself could be seen to rely on differentiated gender ideal-types. in this under- standing, the ‘beautiful soul’s presence is crucial both to wars and their justificatory narratives. ‘beautiful souls’ require protection; the protection of the feminine can then be read as a crucial cause of war. the images of femaleness in the gender- stereotypical ‘beautiful soul’ narrative, then, simultaneously enable war and sub- ordinate women. if this reading of the ‘beautiful soul’ narrative is correct, it will not dis- appear as the nature of war changes and women’s roles in conflict evolve. instead, violence and protection are not opposites, but complementary concepts that necessitate each other: protection requires violence; violence requires protection. without the ‘beautiful soul’ to protect, the just warrior has nothing to excuse (his) fighting, and the justificatory narratives behind the making and fighting of wars are stalled without their victorious conclusion. there is, then, theoretical and empirical leverage to be gained by considering mutual constitution of gender stereotypes and war. if the ‘beautiful soul’ narrative is central to war, and war is central to the building and maintenance of the ‘beautiful soul’ narrative, gender is a lynchpin of war-making, and the war system is a lynchpin of gender subordination. if and to the extent that the above three examples of the ‘beautiful soul’ narrative in the st century demonstrate such a relationship, it is clear that neither is going anywhere in the near future. given this, it is easy to understand why, while several militaries have de- veloped policies specifically aimed at the integration of women into their ranks, those policies have not generally reached the level of ‘mainstreaming’ gender in military organizations. in addition to formal restrictions on which military roles women can fill, and a perceived glass ceiling on women’s advancement in mili- taries, women enter a military that has transformed its ‘gender balance’ while paying ‘little attention to the discursive and performative elements of gender dichotomies’. the result has been ‘the preservation of the discursive structures of gender-subordination even in gender-integrated militaries’. though women in- creasingly fight in wars, they often get caught in a gender-stereotype catch- : they judith stiehm, its our military too! women and the us military, temple university press, philadelphia, pennsylvania, ; francine d’amico and laurie weinstein, gender camouflage: women and the us military, new york university press, new york, ; rachel woodward and trish winter, sexing the soldier: the politics of gender and the contemporary british army, routledge, new york and london, . jacqui true and michael mintrom, ‘transnational networks and policy diffusion: the case of gender mainstreaming’, in international studies quarterly, vol. , no. , , pp. – ; sylvia walby, ‘measuring women’s progress in a global era’, in international social science journal, vol. , no. , , pp. – . shannon l. holland, ‘representations of jessica lynch and the controversy regarding women in combat’, in quarterly journal of speech, vol. , no. , , pp. – . barbara palmer and dennis michael simon, breaking the political glass ceiling: women and congressional elections, routledge, london and new york, . l. sjoberg, above note . ibid. volume number march take all of the risks that men do, while missing both the reward and the elusive status of equality. all the while, elements of the old civilian ‘beautiful soul’ nar- rative remain dominant in accounts of women who share both the responsibility and the cost of fighting wars. ‘gender mainstreaming’, a policy of the consideration of the gender-based impacts of each particular choice made by a government or an organization, has become a popular antidote to gender-subordinating institutional structures in global politics, being adopted by the united nations security council, many other un bodies, the world bank, the international monetary fund, and several gov- ernments around the world. perhaps it is time to ask what a ‘gender mainstreamed’ experience for female soldiers would look like, rather than what it looks like when women are added to militaries with pre-existing value structures biased towards men, masculine ways of thinking, and traits associated with masculinity. there are those that would argue that a ‘gender mainstreamed’ state or non-state fighting force might be a contradiction in terms, since recognizing the gender-differential impacts of the making and fighting of wars would require turning away from war. still, others would suggest that the lives and stories of women soldiers would be substantially different if gender considerations were at the forefront of military policy choices. perhaps ‘gender-mainstreamed’ militaries would recognize women’s agency in their fighting, elements of both the personal and political in soldiers’ motives to fight, military policies which disproportionately affect women while appearing gender neutral (such as haircut rules), intrusions of the ‘beautiful soul’ narrative into the professional lives of women soldiers, the persistent problem of sexual violence in militaries, the masculinism inherent in weapons discourses, the gendered nature of states’ wartime posturing, and other places where the gendered nature of war and gender-based expectations of women soldiers’ behav- iour combine to continue a trend of gender subordination surrounding women’s soldiering – even as women have always had, and continue to have in increasing numbers, important fighting roles in wars and conflicts. l. sjoberg and c.e. gentry, above note . e.g. j.b. elshtain, above note . see e.g. janis karpinski and steven strasser, one woman’s army: the commanding general of abu ghraib tells her story, miramax books, new york, . l. sjoberg, above note . terri spahr nelson, for love of country: confronting rape and sexual harassment in the us military, routledge, new york and london, . carol cohn, ‘sex and death in the rational world of defense intellectuals’, in signs: journal of women in culture and society, vol. , no. , . jennifer heeg maruska, ‘when are states hypermasculine?’, in gender and international security: feminist perspectives, by laura sjoberg (ed.), routledge, new york, , pp. – . l. sjoberg – women fighters and the ‘beautiful soul’ narrative women fighters and the ‘beautiful soul’ narrative women and wars in historical perspective were women ‘beautiful souls’? women soldiers, the ‘war on terror’ and the ‘beautiful soul’ narrative women terrorists and the ‘beautiful soul’ narrative women soldiers in the st century mathematics interdisciplinary research ( ) xx − yy golden ratio: the mathematics of beauty hamid ghorbani⋆ abstract historically, mathematics and architecture have been associated with one another. ratios are good example of this interconnection. the origin of ratios can be found in nature, which makes the nature so attractive. as an example, consider the architecture inspired by flowers which seems so harmonic to us. in the same way, the architectural plan of many well-known historical buildings such as mosques and bridges shows a rhythmic balance which according to most experts the reason lies in using the ratios. the golden ratio has been used to analyze the proportions of natural objects as well as buildings harmony. in this paper, after recalling the (mathematical) definition of the golden ratio, its ability to describe the harmony in the nature is discussed. when teaching mathematics in the schools, one may refer to this interconnection to encourage students to feel better with mathematics and deepen their understanding of proportion. at the end, the golden ratio has been statistically examined using its first decimal digits to show that the golden ratio decimals can be used as a random number generator. keywords: fibonacci sequence, golden ratio, golden rectangular, random number generator. mathematics subject classification: primary a , a , secondary a . how to cite this article h. ghorbani, golden ratio: the mathematics of beauty, math. interdisc. res. ( ) xx-yy. . introduction proportions in geometry, architecture, music and art express the harmonious re- lationships between the whole and its parts, and within a whole system [ ]. the ⋆corresponding author e-mail: hamidghorbani@kashanu.ac.ir academic editor: almantas samalavicius received march , accepted june doi: . /mir. . . c⃝ university of kashan this work is licensed under the creative commons attribution . international license. hamid ghorbani selection and use of systems of proportions has always been a vital issue for artists and architects, see [ ] and [ ]. since that beautiful harmonious sounds depended on ratios, the architects have been considered the ratios when designing a building, see [ ] and [ ]. however, architects have fine senses of symmetry of visual forms without considering a precise definition of this concept from the mathematical point of view [ ]. one of the coolest facets of architecture is the ability to have buildings be so different so varied in terms of size, shape, and style and yet so similar at their core. one way to achieve this is to keep the proportion between the sizes of elements constant. the so-called golden ratio has been applied for centuries to assure a building’s harmony [ ]. in the following sections, first the golden ratio is defined mathematically and introduces later from geometrical point of view. its appearance in nature and architecture are reviewd very briefly. at the end, it is shown that the digits of the golden ration behaves like a random sequence. . the history of the golden ratio about b.c., euclid of alexandria, the most prominent mathematician of an- tiquity, gathered and arranged propositions into thirteen books, entitled the elements [ ], denote by [ab] and ab the closed line segment with endpoints a and b and its length, respectively. in the book vi, he defines that the segment [ab] is divided in extreme and mean ratio by a point c ∈ [ab], if ac < cb and cb ac = ab cb . while the proportion cb ac known as the golden ratio has always existed in mathematics, it is unknown exactly when it was first discovered and applied by mankind. it is reasonable to assume that it has perhaps been discovered and rediscovered throughout history, which explains why it goes under several names, such as golden section, golden mean, golden number, divine proportion, divine section and golden proportion. its beautiful properties has won the interest of many authors, to mentioned [ ] and [ ] among others. many key architects in history, such as, le corbusier [ ], pacioli, and leonardo da vinci have used the golden ratio in their works explicitly. fra luca pacioli, an italian mathematician and painter entered some mathematical basis to painting, published the book de divina proporzione and leonardo da vinci made the illustrations of his book. in addition, many recent publications discussed the appearance of the golden ratio in designing the historical buildings in iran, see [ ] and [ ]. . the golden ratio in mathematics in mathematics two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities. expressed algebraically, for quantities a and b with a > b > , a + b a = a b def = φ, golden ratio: the mathematics of beauty or φ − φ − = , ( ) where, the greek letter phi (φ or ϕ) represents the golden ratio. it is an irrational number (meaning we can not write it as a simple fraction), with a value of: φ = + √ ≈ . . another interesting relationship involving the golden ratio may be obtained di- rectly from: φ = √ + φ, successive substituting the left hand side for φ on the right hand side gives: φ = √ + √ + √ + · · ·. similarly, replacing x = φ in the equation ( ) yields the quadratic equation x + x − = , which its positive root is φ , i.e., φ = √ − φ = √ − √ − √ − · · ·. again, another relationship may be obtained, by using φ = + φ = + + φ = · · · repeatedly, we find that golden ratio is related with the following continued fraction φ = + + + + + · · · . also, any power of φ is equal to the sum of the two immediately preceding powers: φn = φn− + φn− , thus, from computation cost point of view, having the first two values φ = and φ ≈ . , for calculating φn approximately, we can repeatedly apply above recursion relation doing only a single subtraction, rather than a slower multiplication by φ, at each step. . the kepler triangle a kepler triangle is a right triangle with edge lengths in geometric progression. the ratio of the edges of a kepler triangle is linked to the golden ratio φ = + √ hamid ghorbani and can be written: : √ φ: φ, or approximately : . : . . the squares of the edges of this triangle are in geometric progression according to the golden ratio. triangles with such ratios are named after the german math- ematician and astronomer johannes kepler ( - ), who first demonstrated that this triangle is characterized by a ratio between short side and hypotenuse equal to the golden ratio. kepler triangles combine two key mathematical concept, the pythagorean theorem and the golden ratio, that fascinated kepler deeply, as he expressed in this quotation by kepler [ ]: “geometry has two great treasures: one is the theorem of pythagoras, the other the division of a line into mean and extreme ratio. the first we may compare to a mass of gold, the second we may call a precious jewel”. some sources claim that a triangle with dimensions closely approximating a kepler triangle can be recognized in the great pyramid of giza [ ]. . the fibonacci sequence the fibonacci sequence, named after leonardo fibonacci an italian born in ad, also a plot element in “the da vinci code, provides yet another way to derive phi mathematically. the series is quite simple. start with and add to get . then repeat the process of adding each two numbers in the series to determine the next one: , , , , , , , , , , , , , , and so on. this pattern is also found in the diagonals of pascals triangle. the relationship to the golden ratio or phi is found by dividing each number by the one before it. the further you go in the series, the closer the result gets to phi [ ]. for example: = , = , = . , = . , = . , = . , if we go further into the series, it will find that = . . the golden number is not just the limit of the sequence of ( , , , , ... ) , but the sequence of convergent is a sequence of best approximations to φ by rational numbers, see ([ , chapter ]). the relation between the golden ratio formula and fibonacci sequence is known as [ ]. a fibonacci sequence {an} is defined by second-order linear dif- ference equation an+ − an+ − an = with a = , a = , then we have the following lemma [ ]. lemma . . the following relations hold: φn = anφ + an− , n = · · · , − , − , , , , · · · (φ − )n = a−nφ + a−n− . the following shows also that the fibonacci sequence has the analytic form. golden ratio: the mathematics of beauty lemma . . the following relation holds: an = φ − {φn − ( − φ)n}, n = · · · , − , − , , , , · · · . lemma . . the following relations hold: (i) φ = +φ φ = + φ +φ = + φ + φ = + φ + φ = · · · = an+an+ φ an− +anφ ≈ . , (ii) an+an+ φ an− +anφ = · · · = φ− − φ = −φ φ− = φ− φ = φ− = φ , (iii) . . ≈ . . ≈ . . ≈ . ≈ . ≈ ≈ ≈ · · · ≈ . . . the golden rectangular the golden section (or proportion) is the basis of the golden rectangle, whose sides are in golden proportion to each other. the golden rectangle is considered to be the most visually pleasing of all rectangles. a distinctive feature of this shape is that when a square section is removed, the remainder is another golden rectangle; that is, with the same aspect ratio as the first. square removal can be repeated infinitely, in which case corresponding corners of the squares form an infinite sequence of points on the golden spiral, the unique logarithmic spiral with this property. applications appeared in all kinds of design, art, architecture, advertising, packaging, and engineering; and can therefore be found readily in everyday objects. golden rectangles can be found in the shape of playing cards, windows, book covers, file cards, ancient buildings, and modern skyscrapers. many artists have incorporated the golden rectangle in to their works because of its aesthetic appeal. it is believed by some researchers that classical greek sculptures of the human body were proportioned so that the ratio of the total height to the height of the navel was the golden ratio. . the golden ratio in the nature geometric proportions are the fundamental part of the nature which act as the key part of the observed order in the structure of beautiful patterns. consider, for example, the study of pattern observed in leaf-arrangement, on which the leaves spread all around the stem, so that new leaves don’t block sun from older leaves, or so that the maximum amount of rain absorbed down to the roots. this regular arrangement is an important aspect of plant form, known as spiral phyllotaxis and is common in arrangement of seeds, scales on a cone axis, sunflower heads, etc. [ ] and [ ]. since nature has many different methods of survival, we do not see this kind of spiral growth in all plants. a spiral is a curve starts from the origin and moves away from this point as it turn around it. a simple way to rearrange circular (x, y) pints having the same distance from the center into a spiral form is hamid ghorbani (a) the rotation value each time is π ( − √ ). (b) the rotation value each time is π ( − √ ). (c) the rotation value each time is π( − √ ). figure : simulated spirals in a sunflower with different rotation values, source author own programming. to multiply x and y by a factor t which increases for each point and then rotate the point (tx, ty) by angle θ, see figure . to see the difference, three values has been used as rotation parameter for generating the patterns, two of which looks not successful to mimic the sunflowers spirals. . the golden ratio in architecture looking beautiful is an interesting and challenging problem when designing a good structural system. the relationship of smaller parts to the whole can affect whether such system seems threatening, welcoming or impressive. the interrela- tion between proportion and good looking has been employed since the beginning of history in many works of art and architecture. geometrical analysis of many persian historical building has proven that a complete of proportions, in particu- lar the golden ratio, was widely used in persian architecture and it was the basis of persian aesthetics. in many persian building, the plan and elevation were set out in a framework of squares and equilateral triangles, whose intersections gave all the important fixed points, such as the width and height of doors; the width, length and height of galleries. a building was not, therefore a collection of odd components, but a harmonious configuration of proportionally related element, which gave movement to space and satisfied the eye. the golden ratio has been masterly used in the design of the taj-al-mulk dome date a. d., in jami mosque in isfahan. the dome has an outer diameter of . m and height of m from the ground level. its thickness decreases from the base to the apex [ ]. . digits of the golden ratio as a random sequence compare for example the following sequences of heads and tails generated by a fair coin, which have the same ( ) probability of occurring: golden ratio: the mathematics of beauty tthhhthhtthhhthtttht tthhtthhtthhtthhtthh, based on the definition of the ’randomness’ as being unable to ’predict’ future events based on past events, most people would probably agree with the random- ness of the second sequence while the first is not. a sequence of independent random numbers with a specified distribution means that each number was obtained just by chance, have no effect on the observed value of the other sequence numbers, and that each number has a specified probability of falling in any given range of values. a uniform distribution on a finite set of numbers is one in which each possible number is equally probable. in a sequence of (uniform) random digits, each of the ten digits through will occur about of the time. there are many computer aided algorithm developed to produce random num- bers that could be either a binary sequences or an integer sequences. this random number generators are actually deterministic algorithms which produce numbers which we expect to resemble truly random ones in some sense. since fixing the starting point of these deterministic algorithms make it possible to predict the sub- sequently generated numbers perfectly, none of these algorithm can produce truly random numbers. this explains why such numbers are called ’pseudo-random numbers’. random number are used by many practical applications including computer simulations, random sampling, numerical analysis, cryptography and communications industry [ ]. different statistical test are designed to test the null hypothesis (h ) which states a given pseudo-random number generator produces ’sufficiently’ random sequence of numbers for their intended use [ ]. these randomness tests are proba- bilistic and involve two types of errors. if the data is random and (h ) is rejected, type i error is occurred and if the data is non-random and h is accepted, type ii error is occurred. in the following, the first , of decimal digits of golden ratio has been ex- amined to answer the question of whether these digits form a sequence of random digits. these digits were obtained using phicalculator, an easy-to-download-and- use program that compute the golden ratio up to million decimal digits, devel- oped by alireza shafaei, which is available for download through https://alireza- shafaei.software.informer.com. first of all, table shows the frequency of the digits through for the first , decimal digits of the golden ratio, confirming these digits are uniformly distributed. the result of the chi-square test (χ = . , df= , p-value= . ) applied on the counts obtained in table do not reject the null hypothesis that each of the ten digits through has been occurred with probability . then the durbin-watson (dw) test, is used for testing the null hypothesis hamid ghorbani table : counts of the first , decimal digits of golden ratio. digits frequenct digits frequenct claiming the specific lag k autocorrelation in the sequence of the first , decimal digits of the golden ratio is zero. table shows the results of conducting the durbin-watson test for the first through fifth-order autocorrelation of this sequence, which shows no significant autocorrelation through fifth order. the same results are obtained for higher orders of k. therefore, according to the results of both chi-square and dw tests the digits of the first , decimal digits of the golden ratio are indistinguishable from a random sequence. table : durbin-watson test applied on the first , decimal digits of golden ratio. lag autocorrelation d-w statistic p-value + . . . − . . . + . . . + . . . − . . . conflicts of interest. the author declares that there is no conflicts of interest regarding the publication of this article. references [ ] d. biebighauser, testing random number generators, unpublished research paper, university of minnesota, ( ). url ="www- users.math.umn.edu/ garrett/students/reu/prngs.pdf". [ ] l. corbusier, modulor i and ii, translated by p. de francia and r. a. bostock, harvard university press, cambridge, . [ ] l. m. dabbour, geometric proportions, the underlying structure of design process for islamic geometric patterns, front. archit. res. ( ) ( ) − . [ ] r. a. dunlap, the golden ratio and fibonacci numbers, world scientific publishing co., new jersey, . golden ratio: the mathematics of beauty [ ] u. eco, art and beauty in the middle ages, translated by h. bredin, yale university press, new haven, . [ ] k. fink, w. w. beman and d. e. smith, a brief history of mathemat- ics: an authorized translation of dr. karl fink’s geschichte der elementar- mathematik, the open court pub. co., chicago, . [ ] r. herz-fischler, the shape of the great pyramid, wilfrid laurier university press, waterloo, . [ ] g. h. hardy and e. m. wright, an introduction to the theory of numbers, fifth edition. the clarendon press, oxford university press, new york, . [ ] g. l. hersey, architecture and geometry in the age of the baroque, the university of chicago press, chicago, . [ ] m. hejazi, geometry in nature and persian architecture, build. environ. ( ) − . [ ] m. hejazi and f. mehdizadeh saradj, persian architectural heritage: archi- tecture, structure and conservation, wit press, southampton, . [ ] r. v. jean, phyllotaxis: a systemic study in plant morphogenesis, cam- bridge university press, cambridge, . [ ] s. iwamoto and k. akifumi, on golden inequalities, ( ) − . [ ] j. kappraff, a course in the mathematics of design, comput. math. appl. ( - )(part ) ( ) − . [ ] d. e. knuth, the art of computer programming, volume : seminumerical algorithms, addison-wesley professional press, massachusetts, . [ ] m. livio, the golden ratio: the story of phi, the world’s most astonishing number, broadway press, new york, . [ ] n. a. megahed, towards math-based architectural education in egyptian engineering faculties, nexus netw. j. ( ) ( ) − . 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[ ] wikipedia contributors, euclid-wikipedia, the free encyclopedia. url ="https://en.wikipedia.org/wiki/euclid". hamid ghorbani department of statistics, university of kashan, kashan, i. r. iran e-mail: hamidghorbani@kashanu.ac.ir shieldsquare captcha we apologize for the inconvenience... ...but your activity and behavior on this site made us think that you are a bot. note: a number of things could be going on here. if you are attempting to access this site using an anonymous private/proxy network, please disable that and try accessing site again. due to previously detected malicious behavior which originated from the network you're using, please request unblock to site. please solve this captcha to request unblock to the website you reached this page when trying to access https://iopscience.iop.org/journal/ - from . . . on april , : : utc beauty, gender and stereotypes: evidence from laboratory experiments james andreoni university of california - san diego la jolla, ca ragan petrie� georgia state university atlanta, ga november abstract the existence of a beauty premium in the labor market and the male- female wage gap suggests that appearance can matter in the real world. we explore beauty and gender in a public goods experiment and �nd similar e¤ects. we �nd a beauty premium, even though beautiful people contribute, on average, no more or less than others. the beauty premium, however, disappears when we provide information on individual contributions, and becomes a beauty penalty. players seem to expect beautiful people to be more cooperative. relative to these expectations, they appear more sel�sh, which in turn results in less cooperation by others. these appear to be clear examples of stereotyping. we also �nd a substantial bene�t to being male, especially with information. this is primarily due to men being better �leaders.�men tend to make large contributions, and people follow their example and give more in later rounds. �we are grateful to terence burnham, marco castillo, rachel croson, daniel hamermesh, and bart lipman for helpful comments. we also thank the national science foundation for �nancial support. . introduction it is well known from labor market studies that beauty and gender can have big e¤ects on earnings. hamermesh and biddle ( ) have shown a signi�cant premium to beauty, with attractive people earning more money than unattractive people. there is also a signi�cant and persistent male-female wage gap. even when controlling for age and experience, men earn about % more than women (o�neill, , ). while some of these di¤erences can be attributed to labor market factors, much of the beauty premium and wage gap remains unexplained. with labor market studies as inspiration, we look at the returns to beauty and gender in an economic laboratory experiment where there are bene�ts to group cooperation. typically economic experiments take great pains to shield the identities of subjects from each other, and as such have nothing to say about how appearances may a¤ect earnings. instead, we reveal the identities of players to one another by showing their digital photos in the experiment. we �nd that beauty and gender have signi�cant and sometimes unexpected a¤ects on earnings. furthermore, the behaviors and apparent stereotyping we �nd may provide some clues into why gender and beauty are so important in the labor market. the experimental setting we consider is a repeated linear public goods game. while not a direct test of the beauty premium or the wage-gap found in the labor market, a public goods game is nonetheless an interesting institution for exploring how such wage di¤erences can emerge in an employment setting. people often work in teams where shirking cannot always be perfectly monitored. this allows for stereotyping to color evaluations of and reactions to both free riding and generosity, and to a¤ect the productivity of the team. a repeated public goods game o¤ers a setting where stereotyping is possible (in groups of more than two) an important exception to this is research by mobius and rosenblat ( ) who use a labor market experiment to decompose the beauty premium. in their experiment, an employer receives a precise measure of a worker�s productivity from a practice round and decides a wage to pay the worker. the interaction between the employer and worker is one shot, so the employer cannot verify if a beautiful worker was as productive as originally thought. and people have an opportunity to see if their expectations of behavior mesh with actual behavior. when e¤ort is observable, certain people can �set the tone�for the work group. gender and beauty may a¤ect which people in the group may be emulated by others, how much retribution people take against shirkers and how much cooperation is used to reward generosity. in the end, the beauty and gender of the individuals in the group will a¤ect the cooperation and success of the group as a whole, and the earnings of its individual members. in our experiment we show each player the digital photos of all other members of their group each round. we have two conditions, one in which only total group contributions are revealed, and another in which information on each player�s contribution is revealed. our experiments �nd evidence for a beauty premium. this premium, however, disappears once people know exactly what each group member contributed to the public good. when only the total group contribution is observable, attractive men and women make more money than unattractive men and women, even though they are no more or less cooperative, on average, than unattractive people. when individual contributions are observable, the reward to being beautiful disappears. people seem to expect beautiful people to be more cooperative than others, and when their behavior does not meet expectations, people are less cooperative with them. there is also a di¤erence in payo¤s for men and women, but not always favoring men. women make more money than men when only group contributions are known. this can be attributed primarily to the stereotype that women are more helpful. men, however, do best when individual contributions to the group are clearly identi�ed. men earn % more when individual contributions are known, compared to when only group contributions are known. interestingly, women�s payo¤s do not change. this e¤ect can be attributed entirely to men being better �leaders.�they contribute their full endowment more often, and others follow their good example by contributing more in later rounds. with these results, we begin to see some of the underlying factors that could generate both a beauty premium and a wage gap, especially in team work envi- ronments. people give beautiful people the bene�t of the doubt in groups and cooperate more with them, thereby enhancing group welfare. women earn more than men when individual contributions to group output are unknown because they are stereotyped overall to be more helpful. however, once individual con- tributions are known with certainty, the beauty premium disappears and a male premium replaces it. this appears to be due to people being more willing to fol- low the lead of generous men. when a man�s generous contribution is observed, it engenders more cooperation than a similar contribution by a woman. this ef- fect is ampli�ed when the proportion of men in the group is higher, suggesting a kind of generosity-competition among men. as a result, men earn more money in the experiment when individual contributions to group output are known. in our data, the male premium is almost equal in size to the beauty premium. why are these results important? they illustrate how easily subtle sex and beauty stereotypes can in�uence economic outcomes, and suggests that further study on the role of stereotypes in economics could yield important insights. . background in our experiment subjects see the digital photos of their partners on the computer screen when they make their decisions. in half of our sessions we also tell subjects what each member contributed in the prior round. there are three ways this could have an e¤ect. simply showing faces could matter, gender and beauty could matter, and �nally the information on amounts given could matter. there is good reason to expect that simply seeing the faces of partners will a¤ect play. bohnet and frey ( a,b) �nd that visual identi�cation increases cooperation in one-shot prisoner�s dilemma and dictator games, and burnham ( ) reports that giving more than doubles in dictator games when at least one of the partners sees the other�s photograph. scharlemann, eckel, kacelnik, and wilson ( ) see slightly more cooperation when subjects are faced with a photograph of smiling bargaining partners, and eckel and wilson ( ) �nd subjects are more trusting when they see their partner. solnick and schweitzer ( ) report a signi�cant e¤ect of attractiveness on o¤ers received and responses made in ultimatum bargaining games. gender also has been shown to have an important e¤ect on behavior and payo¤s. eckel and grossman ( ) �nd groups of women to be more generous than groups of men in dictator games, while andreoni and vesterlund ( ) �nd women more equalitarian than men in dictator games. buchan, croson, and solnick ( ) report that women are less trusting but more trustworthy than men in an investment game. gneezy, niederle, and rustichini ( ) �nd women to be more productive in competitive-pay environments when in same-sex groups, rather than mixed-sex groups. mobius and rosenblat ( ) use a labor market experiment to decompose the beauty premium. there is also experimental evidence from the sociology and psychology liter- ature that beauty carries a premium. in prisoner�s dilemma games, people are more cooperative with attractive partners (mulford, orbell, shatto, and stockard, ). indeed, in a comprehensive review of the literature on beauty, langlois, klakanis, rubenstein, larson, hallam and smoot ( ) �nd that attractive peo- plearenotonly judgedandtreatedmore favorablybuttheyalsobehavedi¤erently. finally, simply knowing what each other player has chosen can also have an impact. for instance, andreoni and petrie ( ) �nd that cooperation is highest when actions can be linked to the actor. sell and wilson ( ) also �nd posi- tive e¤ects when information is available. but, information may also help adjust judgements. social expectancy theory predicts that if people have di¤erent expec- tations of how, for instance, attractive and unattractive others will behave, then they may have totally di¤erent reactions to the same observed behavior depend- ing on which person they are facing (darley and fazio, ; zebrowitz, ). furthermore, psychologists suggest that people come to the table with prejudices and stereotypes. however, after meeting someone and gaining more information, these prejudices are often revised or washed away (devine, ). related to see eckel and grossman ( ) for a review of gender di¤erences in laboratory experiments. this are issues of similarity and familiarity. people tend to favor those similar to themselves (mcpherson, smith-lovin and cook, ), and working with famil- iar others can reduce transaction costs, as familiarity can enhance trust (glaeser, laibson, scheinkman, and soutter, ). this suggests that people may behave di¤erently with others when they know their decisions, rather than just their appearance, and that people may want to emulate the choices of �similar�others. also, people can use their choices to signal information to others in order to establish a link later (such as getting a date). identi�cation may not only serve to help form impressions before actions, but peo- ple may also use identi�cation as a guideline for judging actions and formulating a response. . methodology our experiments use a linear public goods game. the game is repeated, and subjects make their decisions on a computer. each session has subjects, and they are randomly divided into groups of subjects. in each round a subject is endowed with tokens that could be invested in a private good or a public good. the private good pays $ . per token invested by the individual, and the public good pays $ . per token invested by the entire group. therefore, the marginal return to investing in the public good is . . each subject is paid based on his investment in the private good and the total group investment in the public good. subjects play with the same group of people for rounds, then are randomly re-matched to new groups for another rounds, until they play with �ve di¤erent groups, each for rounds. so, subjects play rounds in total in each session. a digital passport-style photograph is taken of each subject at the beginning of the experimental session. the photo is from the shoulders up and is displayed on top of the screen while subjects make decisions. at the end of each round, the very few subjects knew other subjects in the experiment ( % of the subjects had �never met�any other subject in the experiment). total amount contributed to the public good by all group members is reported. there are two treatments: no information and information. in the information treatment, both the photo and the contribution of that group member from the previous round are displayed. the contribution is listed below each photo, and the photos are rearranged each round with the highest contributor on the left and the lowest on the right. in the no information treatment, only the photos of each group member are displayed on the screen and no information on individual actions is given. all treatments were conducted twice. this gives us subjects in total. sub- jects were recruited from economics and business classes at the university of wis- consin - madison. there were female subjects and male subjects in total, ranging in age from - years (mean . years old). each experimental ses- sion took about an hour and a half, and the average subject payment was $ . (standard deviation $ . ). subsequently, people not involved in the experiments rated each photo as to the person�s physical attractiveness or how helpful looking he/she appears. in total, the raters saw photographs. these photos were of the subjects in the no information and information treatments and other photos of subjects in two other public goods game treatments. these other treatments were not used here as they do not allow a clear test of beauty and gender e¤ects. we chose to have the raters view the subjects randomly mixed among the other photos to get a �global� measure of physical attractiveness and helpfulness. we want to know if a subject is considered physically attractive among his or her peers, not only among the subjects in the session. drawing on this broader distribution of photographs gives us more information and note that, in andreoni and petrie ( ), the no information treatment is called �photos� and the information treatment is called �information-and-photos.� the photos of the other subjects come from the same cohort as the subjects in the no information and information treatments. they were recruited at the same time as the other subjects from economics and business school classes at the university of wisconsin-madison. of the subjects, are male and are female, ranging in age from - years (mean: . years old). con�dence in our classi�cation and subsequent results. each rater rates all photographs along one dimension, physical attractive- ness or helpfulness. the raters view the photos on the computer in a random order, assign a rating, and have the ability to move back to previously rated pho- tos to change or check ratings. raters know they can do this before they begin rating. the raters use a -point scale, with indicating �not at all�and indicat- ing �very much so.�raters are told to think of the number as average. there are raters in total. four women and four men rated each photo in terms of physical attractiveness, and four women and three men rated each photo in terms of helpfulness. the raters were all undergraduates of the university of wisconsin- madison, with an average age of . . the raters were paid a �at fee of $ to rate photographs, and the rating task took - minutes to complete. . beauty classi�cation in this section we discuss our beauty classi�cation methodology, the reliability across those rating beauty, and explain how we de�ne attractiveness. first, we assume the raters use all photos as a frame of reference. when discussing consensus among raters, therefore, we consider the consensus for all photos. also, when de�ning attractiveness, we use all photos as the entire frame of reference. turning to the consensus among raters, the inter-rater reliability for physical attractiveness is . , and for helpfulness it is . . these reliability measures note that similar, yet not as strong, results hold if we de�ne the frame of reference to be only the photos of the subjects in the information and no information treatments. so, it appears that the frame of reference is important in de�ning who is attractive. we opt to base the analysis of this paper on the larger frame of reference because it improves the accuracy and predictive power of our ratings. we use the cronbach coe¢ cient alpha for standardized variables (cortina, ; sas insti- tute inc., ). this measures the correlation between all raters and adjusts for rater speci�c mean and variance. while this rating raises automatically as the number of raters increases (we thank daniel hamermesh for pointing this out), we report it in order to compare with other studies using attractiveness ratings. using an alternative measure of reliability, an intra-class compare well with previous research on attractiveness and suggest a strong con- sensus among raters. our reliability measures also compare well with previous research on attractiveness, where the range of reliability measures is between . and . (langlois et al., ). there is some variability in the spread and average rating any given rater gave. some raters use the entire range from to , but others truncate the range between and . therefore, each rater�s ratings of all photos are standardized by the rater�s mean and standard deviation, resulting in mean zero and standard deviation of one. then, for each subject, we average the standardized ratings across all raters to give a value of physical attractiveness and helpfulness for each subject. these averaged standardized ratings are used throughout the paper. overall, women are rated signi�cantly higher in attractiveness than men. women receive an average standardized rating of . and men - . . the same holds for helpfulness. women were rated, on average, at . and men at - . . that is, women are considered more attractive and more helpful-looking than men. there are, obviously, many ways of de�ning an attractive person. because we wish to examine the e¤ects of beauty on earnings and women are disproportion- ately rated more attractive than men, we take into consideration both gender and beauty rating in our classi�cation. of the subjects, are women and are men. for women, we took the top quartile of the distribution of attractiveness ratings for these women and classi�ed them as attractive. we did the same for the men. then, we took the bottom quartile of the distribution of attractiveness ratings for the women and classi�ed them as unattractive. we did the same for men. anyone in the middle of the distribution was classi�ed as middle attrac- correlation coe¢ cent (two-way random e¤ects model), we �nd similar results. the icc coef- �cient is . . we also �nd strong agreement among men and women in terms of who is attractive. langlois et al. ( ) report an acceptable range of reliability measures is between . and . . the fact that measures fall on the lower end of this range and re�ect our �point scale. most scales were -point or -point. tive. for robustness, we repeated our analysis with both more and less exclusive de�nitions, with nearly identical results. this classi�cation of subjects is also within the range used by hamermesh and biddle ( ), where between %- % of their samples were classi�ed as above average or higher in attractiveness. table distribution of attractiveness women men attractive middle unattractive total the distribution for the subjects considered here is shown in table . by de�nition, there are roughly an equal number of men and women classi�ed as attractive. . results we �rst discuss the beautypremium, thengenderdi¤erences inpayo¤s, and�nally the interaction of beauty and gender. we also classi�ed subjects as attractive and unattractive by using the th-percentile and the th-percentile. results using the th-percentile cut-o¤ are strikingly similar to those using the quartile cut-o¤. results using the th-percentile cut-o¤follow similar trends to those using the quartile cut-o¤, however some results that are statistically signi�cant with the quartile cut-o¤ are not with the th-percentile cut-o¤. note that hamermesh and biddle ( ) did not use the same range of their data to classify people as unattractive. between %- % of their samples were classi�ed as below average or lower in attractiveness. when we did not condition on gender, the distribution of attractive, middle attractive and unattractive subjects across men and women was skewed. women and only men were classi�ed as attractive, and men and only women were classi�ed as unattractive. the distributions of attractiveness are similar across the subjects and the sample of subjects. the hypothesis of independence across the two distributions cannot be rejected by a chi-square test (p-value= . ). . . does beauty pay? first consider the no information treatment. the left-hand side of table shows that there are positive returns to beauty. attractive people make % more than middle attractive people and % more than unattractive people. the returns to beauty are similar to those found by hamermesh and biddle ( ), where above- average attractive people earned about % more than average-attractive people. the di¤erences across the three attractiveness categories are signi�cant. table average payo¤ no information information attractive $ . $ . middle $ . $ . unattractive $ . $ . p-value� . . �joint kruskal-wallis rank sum test for equality of payo¤s across the three categories. while there is evidence for a beauty premium in the no information treat- ment, it disappears in the information treatment. the right-hand side of table illustrates this. in the information treatment, payo¤s appear independent of beauty. we see that returns to beauty are signi�cant, but only when performance cannot be observed. both attractive men and women earn more money. we explore the returns to gender further in section . . next, we ask why the beauty premium might exist. in pair-wise tests using the wilcoxon rank sum test, attractive people make signi�cantly more than middle attractive (p-value= . ) and unattractive people (p-value= . ). how- ever, middle attractive people do not make signi�cantly more than unattractive people. in pair-wise comparisons using a wilcoxon rank sum test, payo¤s are not signi�cantly dif- ferent between attractive, middle attractive, or unattractive people. . . . behavior of attractive people why do attractive men and women make more money? two possible explanations are that they are either more sel�sh or that they engender more cooperation from others. the �rst explanation is explored in table . for the no information treat- ment, the left-hand side of the table shows that attractive people and unattractive people are, on average, less sel�sh than middle attractive people. both attrac- tive and unattractive people contribute between - % of their endowment to the public good, but middle attractive people only contribute %. while the average contribution of an attractive person is signi�cantly di¤erent than that of a middle attractive person, there is no signi�cant di¤erence in contributions of attractive and unattractive people. if higher earnings are due to more sel�shness, then it makes sense that middle attractive people make moremoneythanunattractive people since theycontribute less on average. this also would imply that attractive people would make less money than middle attractive people. but, attractive people make more. while there is no signi�cant di¤erence between the average contribution of an attractive and unattractive person, an attractive person makes $ . more than an unattrac- tive person. sel�sh behavior is not an explanation for why attractive people make more money, but it may explain the higher payo¤ for middle attractive people relative to unattractive people. table average percent contributed per round no information information attractive . . middle . . unattractive . . p-value� . . �joint kruskal-wallis rank sum test for equality of contributions across the three categories. in pair-wise comparisons using a wilcoxon rank sum test, the di¤erence in the average contribution of an attractive person and an unattractive person is insigni�cant (p-value= . ). for the information treatment, the right-hand side of table shows that attractive people contribute less than middle attractive and unattractive people. however, the di¤erence in contributions is not signi�cant, nor are their payo¤s in table . we do not �nd evidence that the beauty premium observed in the no informa- tion treatment is due to more sel�sh behavior by attractive people. indeed, there are no clear trends in contribution behavior and payo¤s. attractive people are no more cooperative than unattractive people, but they still make more money. this suggest that the di¤erence in payo¤s may be due to how others respond to beauty. we explore this next. . . . favoritism and beauty stereotypes could the observed beauty premium be due to favoritism towards attractive peo- ple? if favoritism exists, then we would expect people to react more cooperatively with attractive people than with people who are not attractive. table explores this hypothesis. we compare the average contribution of nonattractive people (those who are classi�ed as middle and unattractive) in groups with no attractive people and in groups with at least one attractive person. we concentrate on the contributions of nonattractive people because we want to isolate the e¤ects of beauty in a group on the behavior of others. in pair-wise comparisons using a wilcoxon rank sum test, there are no signi�cant di¤erences in the average contribution of attractive, middle attractive, or unattractive people. table average percent contributed by nonattractive people in groups of attractive people, all rounds # of attractive people in group no information information all . . . or more� . . . p-value . . . �in the no information treatment, there are groups with one attractive person, with two attractive people, with three attractive people, and with four attractive people. in the information condition, there are groups with one attractive person, with two attractive people, and with three attractive people. table shows that the contributions of nonattractive people depend on the beautyof theothergroupmembers. inthenoinformationtreatment, thepresence of beauty in the group does engender more cooperation. the average percent contributed in groups with no attractive people is . %, but in groups with at least one attractive person, the average increases to . %. this di¤erence is signi�cant and suggests the presence of beauty may engender more cooperation. in the information treatment, however, it is the absence of beauty that engenders more cooperation. the average contribution in groups with at least one attractive person is . %, but in groups with no attractive people, it increases to . %. this di¤erence is also signi�cant, but it contradicts favoritism. why do nonattractive people reverse their behavior from one treatment to the next? one hypothesis is rooted in beauty stereotypes and reciprocity. that is, people are more cooperative with attractive people because they believe attractive people are helpful. langlois et al. ( ) found, in a comprehensive review of the beauty literature, that attractive people are consistently judged and treated more positively. we also �nd this in our ratings data. thirty-eight percent of attractive subjects are also judged helpful looking, % of middle attractive people are also similar results hold if we include the contributions of attractive people. in this case, con- tributions increase to . % in the no information treatment and decrease to . % in the information treatment. this suggests that it is not merely nonattractive people who are af- fected by the presence of attactive people in the group. judged helpful looking, but only % of unattractive people are judged helpful looking. this is remarkable because these ratings are by people who did not observe the decisions of the individuals in the photos and they did not rate the subjects in terms of attractiveness. this suggests that people independentlyexpect attractive people to be more cooperative. while there may be reason to believe such a stereotype exists, it is a bit tricky to tease apart because people may hold stereotypes but not act upon them. however, devine ( ) argues that if people hold stereotypes, once they meet a stereotyped individual and gain more information, they revise or eliminate the stereotype. that is, without information, they act upon the stereotype, but with information, behavior changes. how behavior changes depends on how people revise or react to behavior that does not coincide with the stereotype. if people hold the stereotype that attractive people are cooperative and people wish to reciprocate cooperation, then we should see changes in behavior in two ways. first, without information, people should be more cooperative with attrac- tive people. evidence for this behavioral change can be found in table . without information, we see that nonattractive people are more cooperative in groups with attractive people than in groups with no attractive people, even though we know that attractive people contribute the same, on average, as unattractive people. this result also holds across rounds. there is higher cooperation in groups with attractive people in every round of the -round sequence, with the di¤erence increasing over the rounds. in round one, the di¤erence in cooperation is . percentage points, and in round eight, it is . percentage points. second, with information, we should see di¤erences in behavior in groups with attractive people and in groups without attractive people because people can now compare how the actions of attractive people di¤er from their expectations. how behavior changes depends on whether deviations from expectations are rewarded or punished. in table , we see that with information, on average, nonattractive bosman and van winden ( ) �nd that subjects that expected their partners to share more of the pie than they actually did were more likely to punish in a power-to-take game. people are more cooperative in groups with no attractive people. they contribute % more. could this be punishment of behavior that does not meet expectations? we think so. looking at behavior in the early rounds of the experiment, when people do not have any information on actual behavior, we see that average contributions are higher in groups with at least one attractive person compared to groups with no attractive people. contributions are % and % respectively in the very �rst round. this pattern holds for the �rst three rounds. by round four though, contributions in groups with at least one attractive person start to decline rapidly, and by round , contributions are % in groups with at least one attractive person and % in groups with no attactive people. contributions remain higher in groups with no attractive people for the remainder of the rounds of the experiment. what is remarkable about this result is that if people base reciprocity solely on met or unmet expectations on behavior, then there should be no di¤erence in table . the presence of an attractive person in the group should not matter. that it does suggests that people react di¤erently to the same actions of attractive and unattractive people. in sum, it appears that people discriminate based on beauty stereotypes. at- tractive men and women are given the bene�t of the doubt when group members do not see performance, even though they contribute amounts similar to unattrac- tive men and women. indeed, the presence of beauty engenders more mutual cooperation, and this may explain the beauty premium. however, when group members can evaluate performance, the presence of beauty engenders less cooper- ation. people seem to expect attractive men and women to be more cooperative than average. when they are not, others are less cooperative with them, and the beauty premium disappears. in the very �rst round of the experiment, before any experience is gained with attractive people, there is no signi�cant di¤erence across treatments in the average contribution of nonat- tractive people in groups with attractive people. this suggests that subjects start out with the same beliefs across treatments over the actions of attractive people. . . . gender di¤erences in beauty stereotypes does favoritism di¤er by gender? in the no information treatment, it does not. both nonattractive men and women are signi�cantly more cooperative in groups with attractive people than in groups with no attractive people. in the information treatment, only men signi�cantly decrease their contribu- tions in groups of attractive people compared to groups with no attractive people. in groups with no attractive people, men contribute . %, but this declines to . % in groups with at least one attractive person. women increase their contri- butions, from . % to . %, but this is not signi�cant. this may mean that nonattractive men and women may hold di¤erent beauty stereotypes. or, they may hold the same stereotype, but only men act upon it. these results suggest that there are no gender di¤erences in favoritism, but there may be in beauty stereotypes. in the no information treatment, both men and women are more cooperative with an attractive person in the group. men and women, however, react di¤erently to information and attractive people in the group. in the information treatment, the reduction in contributions in groups of attractive people is driven by the actions of men. . . does gender pay? we now move the focus from beauty to gender. overall, men and women make the same amount of money. table shows that both men and women make around $ . over both treatments. however, women make $ . more than men in the no information treatment, and men make $ . more than women in the information treatment. the former di¤erence is signi�cant at the % level, and the latter is not. strikingly similar results hold if attractive men and women are included in the average. fershtman and gneezy ( ) also �nd that men are more apt to hold and act on stereotypes. using trust experiments, they �nd that men in isreali society are more likely to act on ethnic stereotypes than women. table average payo¤ women men p-value* both treatments $ . $ . . no information $ . $ . . information $ . $ . . p-value* . . �pair-wise wilcoxon test for equality of payo¤s across the two treatments/genders. within gender, women make about the same across treatments. they make $ . in no information and $ . in information. by contrast, the payo¤ for men is % higher in the information treatment compared to the no information treatment. this di¤erence is signi�cant. there is a gender di¤erence, but that switches from favoring women to men when actions are known. there are large bene�ts to information, but only men reap them. again, there are two possible explanations. women could be more sel�sh than men, or men may engender more cooperation with their performance than women. we discuss these possibilities next. . . . behavior of men and women are women more sel�sh than men? table shows that, on average, women are no more or less cooperative than men� men give roughly % more than women, but this is not signi�cant. however, men play the extremes signi�cantly more than women. men contribute zero tokens . % of the time, but women do so only . % of the time. women also contribute all of their tokens only . % of the time, compared to men who do so . % of the time. similar results hold for each treatment separately. men are found to have higher variance in behavior relative to women in other research. an- dreoni and vesterlund ( ) �nd that men are more likely to be completely sel�sh or completely altruistic. pinker ( ) �nds higher variance in the iq scores of men relative to women. table average contribution, zero tokens, and all tokens both treatments men women p-value average contribution (%) . . . % of times zero tokens . . . % of times all tokens . . . this suggests that the gender premium to women is not due solely to more sel�shness on their part. women seemto be bene�ting froma combination of their slightly lowercontributionsandtheirbeauty. while theyarenot signi�cantlymore sel�sh, they are more beautiful, and returns to beauty are high. we return to the interaction of beauty and gender in section . . first, we address the question of why men do better in the information treatment than women. table ols regression coe¢ cients dependent variable: average contribution to the group pooled data model model constant . . ( . ) ( . ) % men in group other than self . - . ( . ) ( . ) % men in group other than self * info . ( . ) individual fixed e¤ects yes yes r . . note: p-values in parentheses, n = . . . �good examples�and sex stereotypes are people more cooperative with men than with women? table reports the results of linear regressions showing how the average individual contribution to the group is a¤ected by the gender composition of the group. the regressions the dependent variable is the average amount a subject contributed to a group over the rounds he played with that group. that is, the average that individual i contributes to group include individual �xed e¤ects. model shows that, over both treatments, as the number of men in the group increases, the average individual contribution of group members increases as well. these e¤ects are signi�cant. this suggests that people cooperate more with men than with women, even though table showed that men give no more on average than women. when we consider treatment e¤ects, model shows that, with information, the cooperation e¤ect of more men in the group increases two fold. without information, the e¤ect is not signi�cantly di¤erent from zero. that is, people are more cooperative in groups with more men only when performance is observable. for example, the average individual contribution to a group where half of the group, other than oneself, is comprised of men will be about tokens higher in the information treatment than in the no information treatment. could this signi�cant increase in cooperation with information be explained by favoritism based on sex stereotypes? if people expect attractive people to be morecooperative, could theyalsoexpectwomentobemorecooperative, especially since theyare ratedhigher inattractiveness? fromourratingsdataonhelpfulness, indeed, more people expect women to be helpful than men, but, perhaps more importantly, more people expect men to be more unhelpful than women. forty- j is de�ned as gij = p t= gijt= . each subject plays with di¤erent groups, so in total, there are observations for the subjects. these are captured with identi�cation dummy variables. note that these variables also capture the treatment e¤ects of information. this is the percent of men in the group other than the subject himself. so, for a group with three men and two women, each man would have % of the group as men, and each woman would have % of the group as men. the dependent variable, average contribution to the public good, is censored at zero and since subjects are only endowed with tokens in each round. although the models in table were run as ols linear regressions, very similar results hold if the models are run as a double-truncated tobit. across treatments, there is no signi�cant di¤erence in the distribution of the gender compo- sition of groups. the p-value for a fischer exact test is . . thus, the signi�cant treatment e¤ects are not due to one treatment having more groups with more men than the other treat- ment. note that this e¤ect also holds for both men and women separately. twenty-�ve percent of women are rated in the upper quartile of helpfulness compared to one percent of men are rated as unhelpful, but only % of women are rated as such. this would suggest that people are more cooperative as the number of men in the group increases because they discover that men are not as unhelpful as they expected. so, even though men give no more on average than women, men may be able to engender more cooperation because they exceed expectations. perhaps a stronger explanation of men�s ability to engender cooperation may come from the �good example�that they set. as noted earlier, men are more likely than women to contribute nothing or contribute their full endowment, but as the number of men in the group increases, the probability of contributing zero declines. a tobit regression on the average probability of contributing zero in a group shows a signi�cant decline in this probability as the percent of men in the group increases. this holds for pooled data, for men only, and for women only. while the probabilityof contributing the �bad�extreme declines with the pres- ence of more men, the probability of contributing the �good�extreme increases, but only for men. table shows how the average probability that a man will contribute the full endowment to the group changes as the percent of men in the group increases. the results for women are similar, but insigni�cant. model shows that men are more likely to contribute all of their tokens as the percent of men in the group increases, and model shows that, when performance is known, men are almost twice as likely to contribute the full endowment. % of men. the dependent variable is the average probability that a subject contributed zero tokens to a group over the rounds he played with that group. that is, the average probability that individual i contributes zero tokens to group j is de�ned as pij = p t= i( jgi = )ijt= , where i(�) is an indicator function that equals when the contribution was tokens. the coe¢ cient on the variable �% men in group other than self�is, b� = � : (s:d: = : ). when performance is known, as in model in table , the probability of free riding declines even further, but the e¤ects are insigni�cant. the dependent variable is the average probability that a subject contributed his full endowment to a group over the rounds he played with that group. that is, the aver- age probability that individual i contributes his full endowment to group j is de�ned as pij = p t= i( jgi = )ijt= , where i(�) is an indicator function that equals when the contri- bution was tokens. table tobit regression coe¢ cients dependent variable: average probability of contributing full endowment men only model model constant - . . ( . ) ( . ) % men in group other than self . - . ( . ) ( . ) % men in group other than self * info . ( . ) individual fixed e¤ects yes yes log-likelihood - . - . note: p-values in parentheses, n= this suggests that the reason that men make more money when performance is known is because they put on a better performance, especially in the presence of other men. moreover, their performance may engender more cooperation from others. while men free ride more than women, they also set a �good example� more than women. as the composition of the group changes from women to men, both men and women free ride less, but men set the �good example�even more. this signi�cantly increases the contributions of others in the group, and men make more money. . . the combined e¤ects of beauty and gender dothee¤ectsof beautyandgenderholdwhenwecontrol for themtogether? table shows the e¤ects of beauty and gender on individual payo¤in each group. the this result is consistent with camerer, ho, chong, and weigelt�s ( ) idea of �strategic teaching.� a person, recognizing that others learn in a repeated game, would make choices to maximize long-run payo¤s. this would suggest that men set a good example to ensure cooperation, and higher earnings, in the future. the dependent variable is the total payo¤a subject earned in a group over the rounds he played with that group. each subject plays with di¤erent groups, so in total, there are observations for the subjects. regressions control for individual and group e¤ects. in the pooled data, the beauty premium holds for attractive and middle at- tractive people, even when controlling for the beauty and gender composition of the group. looking at men and women separately, it is attractive women that gain the beauty premium, but for men, only middle attractive men earn signi�cantly more. interestingly, evenwhencontrolling for individualbeauty, bothmenandwomen earn more money when the number of attractive people in the group increases. the premium to being in the presence of beauty, however, only holds when in- dividual performance is unknown. once the group knows what each individual member contributes, the premium disappears. table shows the e¤ects of beauty and gender on average contributions in each group. as with the payo¤ regressions, these control for individual and group e¤ects. to address unobservable correlation across individuals and across individuals in the same group, the estimates use a two-way random e¤ects error correction model. the dependent variable is the average contribution a subject makes in a group over the rounds he played with that group. each subject plays with di¤erent groups, so in total, there are observations for the subjects. table ols regression coe¢ cients dependent variable: total individual payo¤ (sum across all rounds) with a group pooled women men (n= ) (n= ) (n= ) constant . . . ( . ) ( . ) ( . ) attractive . . . ( . ) ( . ) ( . ) middle attractive . . . ( . ) ( . ) ( . ) # attractive people in group other than self . . . ( . ) ( . ) ( . ) % men in group other than self . . . ( . ) ( . ) ( . ) info . . . ( . ) ( . ) ( . ) attractive*info - . - . - . ( . ) ( . ) ( . ) middle attractive*info - . - . - . ( . ) ( . ) ( . ) # attractive people in group other than self*info - . - . - . ( . ) ( . ) ( . ) % men in group other than self * info . . . ( . ) ( . ) ( . ) individual & group random e¤ects yes yes yes r . . . note: standard errors in parentheses, and signi�cant values (p-value < %) in bold. table ols regression coe¢ cients dependent variable: average contribution to the group pooled women men (n= ) (n= ) (n= ) constant . . . ( . ) ( . ) ( . ) attractive . . . ( . ) ( . ) ( . ) middle attractive - . - . - . ( . ) ( . ) ( . ) # attractive people in group other than self . . . ( . ) ( . ) ( . ) % men in group other than self - . - . - . ( . ) ( . ) ( . ) info - . - . - . ( . ) ( . ) ( . ) attractive*info - . - . - . ( . ) ( . ) ( . ) middle attractive*info . . . ( . ) ( . ) ( . ) # attractive people in group other than self*info - . - . - . ( . ) ( . ) ( . ) % men in group other than self * info . . . ( . ) ( . ) ( . ) individual & group random e¤ects yes yes yes r . . . note: standard errors in parentheses, and signi�cant values (p-value < %) in bold. looking at contributions, we see that average contributions are higher in groups with more attractive people, but only when individual contributions are not revealed. once individual contributions are revealed, people are less coop- erative as the number of attractive people in the group increases. as we saw previously, this change in behavior is driven by men. we also see that people are more cooperative in groups with more men when contributions are known, con�rming earlier results. in sum, when controlling for individual beauty and gender and for the beauty and gender composition of the group, our main results still hold. there is a premium to beauty, but that premium disappears when performance is known. others also bene�t from being in the presence of beauty because people are more cooperative. this monetary return, however, disappear when group members can clearly identify individual contributions. people are far less cooperative as the number of attractive people in the group increases. being in a group with more men does increase average contributions, but only when individual contributions are observed. . discussion and conclusions we used laboratory experiments to examine the returns to beauty and gender in a public goods game. group members were identi�ed with digital passport- style photographs. in one treatment, group members knew only the total amount contributed to the public goodbythe group, while in the other treatment theyalso knew the exact contribution of each group member. subjects�photos were later independently rated in terms of physical attractiveness and how helpful-looking the subject appears. in general, our results show signi�cant and surprising e¤ects of beauty and gender on earnings. when performance is unknown, people tend to reward beauty and females. and, when performance is known, the beauty premium disappears and the female premium switches to a male premium. these results appear to be rooted in beauty and sex stereotypes and have three main components. first, relative beauty is rewarded. attractive people make more money than middle attractive people, who in turn make more money than unattractive peo- ple. this premium to beauty mirrors hamermesh and biddle�s ( ) results and can be quite large. attractive people earn % more than unattractive people. this premium disappears, however, when actions are known. we �nd the beauty premium is not due to the actions of attractive people, but seems to be due to the expectations of how attractive people will behave, as suggested by psychologists� social expectancy theory. people expect beautiful people to be more coopera- tive, and thus behave more cooperatively toward them when they are in the same group. but when information on decisions reveals that attractive people are no more or less cooperative than others, contributions decline relative to groups with no attractive people. this seems to re�ect disappointed stereotypes of attractive people. second, women bene�t for being stereotyped as helpful. women make % more than men when contributions are not known. looking more closely, we �nd the higher payo¤ enjoyed by women is not due to more sel�shness on their part but, rather, may be a consequence of their beauty and sex stereotypes. women are rated signi�cantly higher in attractiveness than men, and their higher payo¤ seems to be the reward to their beauty. also, because women are stereotyped to be more helpful than men, people are more cooperative in groups of women than in groups of men when performance is unknown. third, when performance is known, the gender premium switches from a fe- male premium to a male premium. that is, while women gain the bene�ts of beauty, men gain the bene�ts of information. the payo¤ for men is % higher when performance is known. the payo¤ for women does not change. indeed, this bene�t to information for men is comparable in value to the attractiveness premium for women. why do men attain this information bene�t and women do not? with information on actions, groups with more men are able to engender more cooperation from others. that is, they set good examples that are fol- lowed by others. free riding declines in groups with more men, and, in apparent male-competition, men are more likely to contribute their full endowment as the proportion of men in the group increases. there are obvious implications of these results for experimental methodology. indeed, this work justi�es the extreme measures experimenters take to protect the identities of subjects. but are there implications of the beauty and gender e¤ects we found for the real world? the most striking result from this research is that, on average, men and women did not behave very di¤erently, and attractive people did not behave appreciably di¤erently than unattractive people. nonetheless, beauty and gender had signif- icant e¤ects on earnings. this happened because beauty and gender a¤ect the way people were treated by others. hamermesh and biddle ( ) found that there is some sorting of beautiful people into occupations in which employers report that looks may increase pro- ductivity, such as in sales, but that this is not strong enough to explain much of the premium to beauty. this leaves social e¤ects rather than productivity e¤ects as the natural place to look for explanations. our research suggests one e¤ect of beauty is rooted in stereotypes. beautiful people tend to be in more successful teams because other team members are more cooperative in the presence of beau- tiful people. this is true when e¤ort is not observable, and suggests that a beauty premium may be more likely to exist when productivity is not perfectly observed, implying that beautiful people may also sort into occupations where individual productivity is di¢ cult to measure. this hypothesis could be examined with labor market data. the gender gap can also possibly be explained by a di¤erent stereotype for men. while beautiful people bene�t from a stereotype of being more cooperative teammembers, men inourexperimentbene�t fromexceedingthe lowexpectations others have for them. people seem to expect men to be less helpful than they are. when they see men exceeding expectations, they respond by following their lead. men may be seen as better leaders despite the expectation that they are more sel�sh. in addition, when men are in groups together, they bene�t from a kind of male-competitiveness for contributing to the public good. in the end, men are more likely to be in successful groups when information on contributions is known, and the more men in the group the greater the advantage to men. this again suggests hypotheses that can be tested with labor market data. professions where e¤ort can be veri�ed more easily may favor men, and male-dominated professions may also have a bigger wage gap. this paper illustrates the possibility for subtle stereotypes to have major eco- nomic impacts. however, economists are only beginning to consider seriously causes and consequences of stereotypes. further work� including theory, policy and experiments� could fruitfully shed light on this important issue. references andreoni, james and ragan petrie ( ), �public goods experiments without con�dentiality: a glimpse into fund-raising,� journal of public economics, ( - ), - .. andreoni, james and lise vesterlund ( ), �which is the fair sex? 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( ), reading faces: window to the soul?, boulder, co:westview press. guest editorial: truth, beauty, and supergravity stanley deser citation: american journal of physics , ( ); doi: . / . view online: http://dx.doi.org/ . / . view table of contents: http://aapt.scitation.org/toc/ajp/ / published by the american association of physics teachers http://jobs.aapt.org/ http://aapt.scitation.org/author/deser% c+stanley /loi/ajp http://dx.doi.org/ . / . http://aapt.scitation.org/toc/ajp/ / http://aapt.scitation.org/publisher/ guest editorial guest editorial: truth, beauty, and supergravity (received june ; accepted june ) [http://dx.doi.org/ . / . ] i begin with a warning: theoretical physics is an edifice built over the centuries by some of mankind’s greatest minds, using ever more complicated and sophisticated concepts and mathematics to cover phenomena on scales billions of times removed—in directions both bigger and smaller—from our human dimensions, where our simple intuition or primitive language cannot pretend to have any validity. so any popular discussion is necessarily impressionistic, being couched in terms of classical analogies that do not really apply. this warning label should be attached to all such accounts, the pre- sent one included. however, i have tried to focus here on an aspect that involves more human attributes of our subject. all theoretical physicists sooner or later grapple with the role of beauty, often also called elegance, in confirming the correctness of our natural laws. in part, this is a problem of language: any “good” theory acquires beauty as its correct- ness is confirmed—we find hidden aspects to marvel at. conversely, those models that do not seem to be used by nature despite their apparent formal attractions eventually lose their luster. yet there is some deep sense in which the two—truth and beauty—are linked. among our great scien- tists, the range goes from boltzmann who said “eleganz ist f€ur schneider,” elegance is for tailors, to einstein for whom beauty would force the lord to accept a theory, despite apparent experimental contradictions, as was eminently the case for special—and to a lesser extent—general—relativity, and even more so in the recent history of our “standard mod- el” of the basic microscopic laws of nature. newton’s famous remark about picking up pretty pebbles at the sea- shore, instead of facing the vast ocean of truth lying just beyond, seems to exhibit a more ambivalent attitude. i chose supergravity (sugra) to illustrate this topic because it is of one of our most recent and conceptually most novel entries: it is just over four decades old, and already has a literature of about papers! this model, along with its wider, and also recent, ancestor, supersymmetry (susy), thus provides a perfect, fresh, case study. sugra also cov- ers a broad canvas, including general relativity, quantum field theory and their unification, which is currently our sub- ject’s holy grail, not to mention its being a limit of super- string theory. i shall of course avoid scaring you, with long—indeed, with any—formulas; yet i emphasize that, as einstein said, things should be stated as simply as possible, but not more simply! to set the background, one of the equations most perfectly beautiful and most perfectly in accord with nature is the dirac equation governing the behavior of electrons—as well as all the other leptons and quarks, hence also our protons and neutrons. indeed, it is perhaps one of our three most beautiful equations, along with maxwell’s and einstein’s! it came full-blown from the head of one of the true greats of the last century, and instantly divided all particles into two antipodal types, the bosons, e.g., mesons and photons that like to congregate (think of intense laser beams) and the fer- mions that maximally hate to do so (pauli’s exclusion principle). once invented, any interesting equation in physics is just asking to be generalized, and there are always people willing to oblige. in dirac’s case, his equation—which only makes sense at the quantum field theoretical, rather than classical, level—describes particles with intrinsic spin, like little tops, but the spin is necessarily fixed to be one half unit of the basic value, namely, the famous planck constant that started all quantum theory off back in . the next possible allowed values for a fermion would be / , / … units. the fact that no such elementary particles had ever been seen was no obstacle, and in due course the counterpart of the dirac equation for spin / was produced, with and without mass—it is the latter we shall use. indeed mass and spin are the two intrinsic parameters that label any particle or field (the two words are interchangeable in the quantum world). there matters rested until the “super” revolution began to take hold in the early nineteen seventies. i must remind you a bit about general relativity (gr). its absolutely novel point was to make geometry, so familiar for millenia as the passive theater in which matter interacts, into a dynamical entity of its own, subject to laws of motion—here the einstein equations—rather than fixed once for all by fiat— indeed geometry was (almost) the last “a priori” to fall; “why” our space-time has (effective) dimension is still open! those einstein equations specify how geometry reacts to—and determines the course of—matter, that is, of all other fields. further, they are universal in that all matter must inter- act uniformly with gravity: none is exempt and indeed geome- try necessarily interacts with itself as well. all these crazy- seeming ideas have observational consequences that include newton’s old universal law of gravitation but in a far more coherent and general way, with predicted corrections that have always been verified and never contradicted. the latest, truly spectacular, triumph involves the (now several) observa- tions of gravitational waves—incredibly tiny spacetime oscil- lations that were predicted a century ago when gr was am. j. phys. ( ), november http://aapt.org/ajp vc american association of physics teachers http://dx.doi.org/ . / . http://crossmark.crossref.org/dialog/?doi= . / . &domain=pdf&date_stamp= - - invented, but only observed in the past year by the unbeliev- ably refined laser beam detectors of ligo; even better, these waves could be traced back to another crazy prediction of gr, namely, black holes, whose collisions emit them as debris. so we can certainly believe einstein’s theory, though as with any theory, only at the scales where it has proved reliable—here a pretty hefty stretch from the (pretty small, if still classical) to the very (cosmologically) big. let me also remind you of einstein’s dream, that of unifi- cation of geometry and matter into a unitary whole. this dream became his late years’ obstinate, but fruitless, quest, although it did lead to many unexpected new concepts: in particular that our universe may exist in more than four dimensions; this in turn became an essential aspect of string theory. i should end this snapshot of gr by noting that gravi- tational waves consist, at quantum level, of bosonic particles that we call gravitons, just as the familiar electromagnetic spectrum is made of photons, also bosonic, that is integer spin, with respective values ( , ). furthermore, gr has the dual quality of also being expressible as a theory of “normal” matter, in which its geometrical aspects are exchanged for a well understood, dynamical matter-like, description; it is as beautiful in this dual way as it is geometrically. so here is pure geometry on the one hand and brute matter on the other, in particular those strange, but essential fer- mions of which we are made. surely unification could never wed these antipodal concepts, or could it? this is the realm of our newest playground, susy, discovered in moscow in and independently in new york a few years later, and also traceable to early string theory. i must now give you a few words about this—yes, extremely beautiful by unani- mous physicists’ consent—concept. let’s take a step back: historically, the greatest progress in physics was the notion of invariance under some set of transformations—think of the most elementary: rotations and translations in our ordinary euclidean three-dimensional space—the world still looks the same even if you move uni- formly in some fixed direction (per galileo) or turn your chair to another angle and location. this notion can be gener- alized to more abstract spaces, but with the same underlying idea. the spaces may be labelled by some properties of a set of particles, all of which behave similarly under various interchanges between them in certain contexts. so susy would put bose and fermi particles on an equal footing under certain “rotations,” without taking away their distinc- tive crowd behaviors. this step has generated an absolutely enormous physical and mathematical literature. indeed, the lhc accelerator at cern was designed not only to seek the spin “higgs” boson (which it found), but also to find traces of susy, that is, the opposite-polarity “super” companions of the known particles. that’s a lot of hard lore to digest, but just think of the rotation invariance analogy, in which the angle of rotation represents mixing of the x- and y-axes here represents mixing bosons and fermions, of adjoining spin like / and —dirac-like particles and photon-like ones. that’s it—“reader’s digest” susy! the elegance of our other pillar of fundamental physics, the “standard model” describing all known matter in a unified way, is a mixed bag, while being an absolutely cor- rect and universal—as measured to date—“true” description of matter’s behavior. we have come to love it for that, but not for its some twenty free parameters nor for its seemingly haphazard cascade of invariances—we sympathize with the eminent elder statesman isidore rabi, who exclaimed about an especially odd new particle, “who ordered that?” yet there has never been a truer or more encompassing edifice than the standard model. so here we (almost) are, trying to make the most elegant of all theories, unifying einstein’s and (generalized) dirac’s equations, a combination of adjoining spins ð ; = Þ, just crying out to be joined a la susy. the payoff is nothing less than, as mentioned, the eternal dream of unifying geometry—that is space, with not just any matter, but fermi- onic matter, at that! indeed, in a technical sense, the dirac part would be the (spinorial) square root of gravity. to spare you the suspense, this attempt was successful—made inde- pendently and simultaneously—just years ago, by two separate groups. actually, sugra is even more beautiful that mere susy, because it enjoys a much deeper “local rotation” gauge invariance. even more serendipitously, the combined equations governing it are the simplest possible, with the least baroque, “minimal” interaction between gr and its spin / source, later extended to include combina- tions of all lower ðs ¼ ; = ; Þ spin fields. the flip side is that no such new particles have yet been found, nor has any type of sugra (yet) been shown to be free of the dreaded closed loop infinities that plague ordinary gr. now comes the time for the punchline—wise general remarks regarding truth and beauty in physics, as exempli- fied by sugra. let’s summarize what we have described so far. there are certain ideas, equations and theories in physics that are almost universally recognized by its practi- tioners as beautiful and elegant. this may occur quite inde- pendently of their empirical or observational verifications; indeed, it often occurs despite the apparent clash between their predictions and experiment. we emphasized that this was the case for some of the most sublime examples—exam- ples that were later vindicated—such as gr and the dirac equation. of course the eye of the beholder is conditioned by education, experience and the collectively accepted state of the art, all rather subjective criteria: newton could not have directly understood the wonders of dirac’s or maxwell’s or schr€odinger’s equations (although he would have caught on quickly, and then surely agreed). that it requires a trained practitioner to appreciate the lightning stroke of a new crea- tion holds true for the arts as well. it is perhaps more surpris- ing, in view of the popular image of the scientist, that elegance and beauty play such leading roles, and it must also be admitted, as i mentioned, that a concept that provides widespread empirical unification will thereby acquire esthetic value, simply from the many unexpected facets its usage uncovers. our chosen example, sugra, certainly qualifies on the elegance and beauty scales, if only because of its parent the- ories, those of einstein and dirac. right from its birth, it felt like a new art form. on the truth front, however, it’s been am. j. phys., vol. , no. , november guest editorial another story altogether: no elementary spin / fermion has ever been found, even in some implicit way, nor indeed have any of the companion particles predicted more broadly by susy. they could be lurking just outside the range of lhc or current cosmological observations. but at present, it must be acknowledged that there is no evidence at all that nature agrees with the esthetic appeal. and i must emphasize that in the end, if the next scale our instruments can probe still fails to find them, they would exemplify boltzmann’s dictum that only tailors would find sugra compelling. yet, at the very least, important theoretical advances have been made in our understanding of pure gr, just by knowing that it can be uni- fied with spin / matter, whether or not it is so unified! truth, by contrast with beauty, would seem to be a far sim- pler, more direct, aspect of physics: after all, when a theory is verified to many decimal places (as many as in some cases!) in widely different areas, it hardly seems worth even questioning its “truth.” yet, here too, things are far less simple than they would seem. the best example is qed, quantum electrodynamics, the basis for all atomic phenomena, the the- ory that occupied much of th century and over half of th century experimental and theoretical research. it is unsur- passed, of all human endeavors, in the accuracy and correct- ness of all its predictions (those decimal places), is certainly beautiful and simple to state (being the quantum expression of the dirac plus maxwell equations), but is equally certain to be wrong at a more fundamental level: when pushed too far, it is revealed to be full of internal contradictions and loss of predictive power. yet there is no doubt whatever that its incredibly accurate predictions in its domain of validity are entirely valid and reliable! on the other hand, a recent exten- sion of qed, called qcd for quantum chromodynamics, reigns unchallenged in explaining the subnuclear domain gov- erning quarks in the standard model. it is fully as beautiful as qed, although initially regarded as a bit of an ugly duckling, even by its discoverers. its most basic “prediction,” confine- ment, that we believe makes quarks condense permanently into our protons and neutrons, has never yet been entirely proven, nor has it ever been seriously doubted! i don’t mean to exhibit these (only apparent) pathologies in our physics thinking in a pejorative way. quite the con- trary, i mean to give a flavor of what the elaborate work of so many physicist-lifetimes has been distilled to. physics is most likely a never-ending quest, not just in the poetic sense, but literally, according to the beautiful concept i end with: kenneth wilson’s (and others’) ideas of the unfolding of novel conceptual aspects of the universe as one widens the scale of enquiry, all in a very concrete well-founded sense. that is perhaps the most beautiful idea of all! this work was supported by grants nsf phy- and doe#desc . an earlier version appeared on the prc mr. science program; the author thanks a. zee for inviting it. finally, the author thanks j. franklin for translating his manuscript into ajp-ese. a somewhat longer version was posted on the arxiv. a technical discussion of sugra’s formal attractions is given in ref. , while a historical account of how the theory came into being may be found in ref. . a) electronic mail: deser@brandeis.edu s. deser and b. zumino, “consistent supergravity,” phys. lett. b ( ), – ( ); d. z. freedman, p. van nieuwenhuizen, and s. ferrara, “progress toward a theory of supergravity,” stony brook university pre- print itp- - ; phys. rev. d ( ), – ( ). k. g. wilson and john b. kogut, “the renormalization group and the epsi- lon expansion,” phys. rept. ( ), – ( ). s. deser, “truth, beauty and supergravity,” e-print arxiv: : . d. z. freedman, “some beautiful equations of mathematical physics,” e-print arxiv: . s. deser, “a brief history of supergravity: the first three weeks,” e-print arxiv: . . stanley deser a) walter burke institute for theoretical physics, california institute of technology, pasadena, california and physics department, brandeis university, waltham, massachusetts am. j. phys., vol. , no. , november guest editorial mailto:deser@brandeis.edu http://dx.doi.org/ . / - ( ) - http://dx.doi.org/ . /physrevd. . http://dx.doi.org/ . / - ( ) - http://arxiv.org/abs/ : http://arxiv.org/abs/ http://arxiv.org/abs/ . n c c c c c _bmjspcare_toc.indd abstracts bmj supportive & palliative care ; : – p small is beautiful lucinda stubbs st. michaeĺ s hospice (north hampshire), basingstoke, uk . /bmjspcare- - . something’s it’s the small things…. in summer we picked up an great idea from the ncpc for ‘small is beautiful’ aimed to get patient and carer feedback on what small things make a difference to them. not only did the team at st. michael’s hospice think this was a fantastic idea but it also fi tted nicely with our commitment to using feedback to guide service development and improve the way in which we work. while we felt it was important to know what our patients and families thought of the hospice we also used it as an opportunity for staff and volunteers to feedback their thoughts. some of our patient comments: feeling cared for. ▶ a home from home. ▶ thank you for the cake, it was yummy! ▶ treating each other as special. ▶ being offered some lunch during a long visit, thank you so ▶ very much. thanks for the comfortable sofas! ▶ with regards to staff and volunteer feedback we have imple- mented many new initiatives including a rolling educational programme, a monthly staff bulletin, more social events and most importantly improved the quality of our tea bags! we ran the campaign for weeks and produced boards which were displayed in patient areas, the hospice staff room and our seven hospice shops. people could put their comments on the board. it was an interesting exercise for us all and provided us with a better understanding of what is important to our visitors and staff and allowed us to make some simple but necessary changes to the way in which we work. we hope to continue building on this in the future and plan to run the small is beautiful campaign again in april where no doubt we will receive some more interesting comments. _bmjspcare- - .indd sec : _bmjspcare- - .indd sec : / / : : pm / / : : pm co p yrig h t. o n a p ril , b y g u e st. p ro te cte d b y h ttp ://sp ca re .b m j.co m / b m j s u p p o rt p a llia t c a re : first p u b lish e d a s . /b m jsp ca re - - . o n s e p te m b e r . d o w n lo a d e d fro m http://spcare.bmj.com/ untitled university of birmingham study of beauty hadron decays into pairs of charm hadrons lhcb collaboration doi: . /physrevlett. . license: creative commons: attribution (cc by) document version publisher's pdf, also known as version of record citation for published version (harvard): lhcb collaboration , 'study of beauty hadron decays into pairs of charm hadrons', physical review letters, vol. , no. , . https://doi.org/ . /physrevlett. . link to publication on research at birmingham portal general rights unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. the express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. • users may freely distribute the url that is used to identify this publication. • users may download and/or print one copy of the publication from the university of birmingham research portal for the purpose of private study or non-commercial research. • user may use extracts from the document in line with the concept of ‘fair dealing’ under the copyright, designs and patents act (?) • users may not further distribute the material nor use it for the purposes of commercial gain. where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. when citing, please reference the published version. take down policy while the university of birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive. if you believe that this is the case for this document, please contact ubira@lists.bham.ac.uk providing details and we will remove access to the work immediately and investigate. download date: . apr. https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . https://research.birmingham.ac.uk/portal/en/publications/study-of-beauty-hadron-decays-into-pairs-of-charm-hadrons( a fc - ff - d -abfb- cd cb ).html study of beauty hadron decays into pairs of charm hadrons r. aaij et al.* (lhcb collaboration) (received march ; published may ) first observations of the decays Λ b → Λ þ c d − ðsÞ are reported using data corresponding to an integrated luminosity of fb− collected at and tev center-of-mass energies in proton-proton collisions with the lhcb detector. in addition, the most precise measurement of the branching fraction bðb s → dþd−s Þ is made and a search is performed for the decays b ðsÞ → Λ þ c Λ − c . the results obtained are bðΛ b → Λþc d−Þ=bðΛ b → Λþc d−s Þ ¼ . � . ðstatÞ � . ðsystÞ;� bðΛ b → Λþc d−s Þ bðb̄ → dþd−s Þ � = � bðΛ b → Λþc π−Þ bðb̄ → dþπ−Þ � ¼ . � . ðstatÞ � . ðsystÞ; bðb s → dþd−s Þ=bðb̄ → dþd−s Þ ¼ . � . ðstatÞ � . ðsystÞ; bðb̄ → Λþc Λ−c Þ=bðb̄ → dþd−s Þ < . ½ % c.l.�; bðb s → Λþc Λ−c Þ=bðb s → dþd−s Þ < . ½ % c.l.�: measurement of the mass of the Λ b baryon relative to the b̄ meson gives mðΛ bÞ − mðb̄ Þ ¼ . � . ðstatÞ � . ðsystÞ mev=c . this result provides the most precise measurement of the mass of the Λ b baryon to date. doi: . /physrevlett. . pacs numbers: . .mr, . .−a hadrons are systems of quarks bound by the strong interaction, described at the fundamental level by quantum chromodynamics (qcd). low-energy phenomena, such as the binding of quarks and gluons within hadrons, lie in the nonperturbative regime of qcd and are difficult to calculate. much progress has been made in recent years in the study of beauty mesons [ ]; however, many aspects of beauty baryons are still largely unknown. many decays of beauty mesons into pairs of charm hadrons have branching fractions at the percent level [ ]. decays of beauty baryons into pairs of charm hadrons are expected to be of compa- rable size, yet none have been observed to date. if such decays do have sizable branching fractions, they could be used to study beauty-baryon properties. for example, a comparison of beauty meson and baryon branching frac- tions can be used to test factorization in these decays [ ]. many models and techniques have been developed that attempt to reproduce the spectrum of the measured hadron masses, such as constituent-quark models or lattice qcd calculations [ ]. precise measurements of ground-state beauty-baryon masses are required to permit precision tests of a variety of qcd models [ – ]. the Λ b baryon mass is particularly interesting in this context, since several ground-state beauty-baryon masses are measured relative to that of the Λ b [ ]. this letter reports the first observation of the decays Λ b → Λ þ c d − s and Λ b → Λ þ c d −. the decay Λ b → Λ þ c d − s is used to make the most precise measurement to date of the mass of the Λ b baryon. improved measurements of the branching fraction bðb s → dþd−s Þ and stringent upper limits on bðb ðsÞ → Λþc Λ−c Þ are also reported. charge con- jugated decay modes are implied throughout this letter. the data used correspond to an integrated luminosity of and fb− collected at and tev center-of-mass energies in pp collisions, respectively, with the lhcb detector. the lhcb detector is a single-arm forward spectrometer covering the pseudorapidity range < η < , described in detail in refs. [ – ]. samples of simulated events are used to determine selection efficiencies, to model candidate distributions, and to investigate possible background con- tributions. in the simulation, pp collisions are generated using pythia [ ] with a specific lhcb configuration [ ]. decays of hadronic particles are described by evtgen [ ], in which final-state radiation is generated using photos [ ]. the interaction of the generated particles with the detector and its response are implemented using the geant toolkit [ ] as described in ref. [ ]. in this analysis, signal beauty-hadron candidates are formed by combining charm-hadron candidate pairs recon- structed in the following decay modes: dþ → k−πþπþ, dþs → k −kþπþ, and Λþc → pk −πþ. the measured invari- ant mass of each charm-hadron candidate, the resolution on * full author list given at the end of the article. published by the american physical society under the terms of the creative commons attribution . license. further distri- bution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and doi. prl , ( ) p h y s i c a l r e v i e w l e t t e r s week ending may - = = ( )= ( ) - © cern, for the lhcb collaboration http://dx.doi.org/ . /physrevlett. . http://dx.doi.org/ . /physrevlett. . http://dx.doi.org/ . /physrevlett. . http://dx.doi.org/ . /physrevlett. . http://creativecommons.org/licenses/by/ . / http://creativecommons.org/licenses/by/ . / which is about − mev=c , is required to be within mev=c of the nominal value [ ]. to improve the resolution of the beauty-hadron mass, the decay chain is fit imposing kinematic and vertex constraints [ ]; this includes constraining the charm-hadron masses to their nominal values. to suppress contributions from noncharm decays, the reconstructed charm-hadron decay vertex is required to be downstream of, and significantly displaced from, the reconstructed beauty-hadron decay vertex. a boosted decision tree (bdt) [ ] is used to select each type of charm-hadron candidate. these bdts use five variables for the charm hadron and for each of its decay products. the variables include kinematic quantities, track and vertex qualities, and particle identification (pid) infor- mation. the signal samples used to train the bdts are obtained from large data sets of b̄ →dþπ−, b̄ s →d þ s π −, and Λ b → Λ þ c π − decays that are background subtracted using weights [ ] obtained from fits to the beauty-hadron invariant mass distributions. the background data samples are taken from the charm-hadron and high-mass beauty- hadron sidebands in the same data sets. to obtain the bdt efficiency in a given signal decay mode, the kinematical properties and correlations between the two charm hadrons are taken from simulation. the bdt response distributions are obtained from independent data samples of the decays used in the bdt training, weighted to match the kinematics of the signal. because of the kinematic similarity of the decays dþ → k−πþπþ, dþs → k −kþπþ, and Λþc → pk −πþ, cross feed may occur among beauty-hadron decays into pairs of charm hadrons. for example, cross feed between dþ and dþs mesons occurs when a k −hþπþ candidate is reconstructed in the dþ mass region under the hþ ¼ πþ hypothesis and in the dþs mass region under the h þ ¼ kþ hypothesis. in such situations, an arbitration is performed: if the ambiguous track (hþ) can be associated to an oppositely charged track to form a ϕð Þ → kþk− candidate, the kaon hypothesis is taken, resulting in a dþs assignment to the charm-hadron candidate; otherwise, stringent pid requirements are applied to hþ to choose which hypothesis to take. the efficiency of these arbitra- tions, which is found to be about % per charm hadron, is obtained using simulated signal decays to model the kinematical properties and d�þ → d πþ calibration data for the pid efficiencies. the misidentification probability is roughly % per charm hadron. signal yields are determined by performing unbinned extended likelihood fits to the beauty-hadron invariant- mass spectra observed in the data. the signal distributions are modeled using a so-called apollonios function, which is the exponential of a hyperbola combined with a power- law low-mass tail [ ]. the peak position and resolution parameters are allowed to vary while fitting the data, while the low-mass tail parameters are taken from simulation and fixed in the fits. four categories of background contributions are consid- ered: partially reconstructed decays of beauty hadrons where at least one final-state particle is not reconstructed; decays into a single charm hadron and three light hadrons; reflections, defined as cases where the cross-feed arbitra- tion fails to remove a misidentified particle; and combi- natorial background. the only partially reconstructed decays that contribute in the mass region studied are those where a single pion or photon is not reconstructed; thus, only final states comprised of d�þðsÞ or Σ þ c and another charm hadron are considered (e.g., Λ b → Λ þ c d �− s ). these back- ground contributions are modeled using kernel probability density functions (pdfs) [ ] obtained from simulation; their yields are free to vary in the fits. single-charm back- grounds are studied using data that are reconstructed outside of a given charm-hadron mass region. these backgrounds are found to be oð %Þ of the size of the signal yield for signal decays containing a d−s (e.g., b̄ → dþk−kþπ−) and are negligible otherwise. the only non-negligible reflection is found to be Λ b → Λ þ c d − s decays misidentified as Λþc d − candidates. the invariant-mass distribution for this reflection is obtained from simulation, while the normali- zation is fixed using simulation and the aforementioned pid calibration sample to determine the fraction of Λ b → Λ þ c d − s decays that are not removed by the cross-feed criteria. reflections of b̄ → dþd−s decays misidentified as final states containing Λþc particles do not have a peaking structure in the beauty-hadron invariant mass and, therefore, are absorbed into the combinatorial backgrounds, which are modeled using exponential distributions. figure shows the invariant mass spectra for the Λ b → Λ þ c d − s and Λ b → Λ þ c d − candidates. the signal yields obtained are � and � for Λ b → Λþc d−s and Λ b → Λ þ c d − , respectively. this is the first observation of each of these decays. the ratio of branching fractions determined using the nominal d−s [ ] and d − [ ] meson branching fractions and the ratio of efficiencies is bðΛ b → Λþc d−Þ bðΛ b → Λþc d−s Þ ¼ . � . ðstatÞ � . ðsystÞ: the similarity of the final states and the shared parent particle result in many cancellations of uncertainties in the determination of the ratio of branching fractions. the remaining uncertainties include roughly equivalent contri- butions from determining the efficiency-corrected yields and from the ratio of charm-hadron branching fractions (see table i). the dominant contribution to the uncertainty of the fit pdf is due to the low-mass background contribu- tions, which are varied in size and shape to determine the effect on the signal yield. the uncertainty due to signal model is found to be negligible. the efficiencies of the cross feed and bdt criteria are determined in a data-driven manner that produces small uncertainties. the observed ratio is approximately the ratio of the relevant quark-mixing prl , ( ) p h y s i c a l r e v i e w l e t t e r s week ending may - factors and meson decay constants, jvcd=vcsj × ðfd=fdsÞ ≈ . , as expected assuming nonfactorizable effects are small. the branching fraction of the decay Λ b → Λ þ c d − s is determined relative to that of the b̄ → dþd−s decay. using dþd−s bdt criteria optimized to maximize the expected b̄ significance, � b̄ → dþd−s decays are obs- erved (see fig. ). the measurement of bðΛ b → Λþc d−s Þ= bðb̄ → dþd−s Þ is complicated by the fact that the ratio of the Λ b and b̄ production cross sections, σðΛ bÞ=σðb̄ Þ, dependson the pt ofthe beauty hadrons [ ].figure shows the ratio of efficiency-corrected yields, nðΛ b → Λþc d−s Þ= nðb̄ → dþd−s Þ, as a function of beauty-hadron pt. the ratio of branching-fraction ratios is obtained using a fit with the shape of the pt dependence measured in bðΛ b → Λþc π−Þ=bðb̄ → dþπ−Þ [ ] and found to be � bðΛ b → Λþc d−s Þ bðb̄ → dþd−s Þ � = � bðΛ b → Λþc π−Þ bðb̄ → dþπ−Þ � ¼ . � . ðstatÞ � . ðsystÞ: this result does not depend on the absolute ratio of production cross sections or on any charm-hadron branching fractions.the systematicuncertaintiesonthisresultarelisted in table i. the uncertainty in the fit model is due largely to the sizable single-charm background contributions to these modes and to contributions from the fits described in ref. [ ]. the bðΛ b → Λþc π−Þ=bðb̄ → dþπ−Þ result was obtained only using data collected at ffiffiffi s p ¼ tev. the ratio nðΛ b → Λþc d−s Þ=nðb̄ → dþd−s Þ is observed to be con- sistent in data collected at ffiffiffi s p ¼ and tev. the statistical uncertainty on this comparison is assigned as the systematic uncertainty on the energy dependence of the Λ b and b̄ production fractions. the ratio of branching ratios is con- sistent with unity, as expected assuming small nonfactoriz- able effects. the kinematic similarity of the decay modes Λ b → Λþc d − s and b̄ → dþd−s permits a precision measurement of the mass difference of the Λ b and b̄ hadrons. the relatively small value of ½mðΛ bÞ − mðΛþc Þ − mðd−s Þ� − ½mðb̄ Þ − mðdþÞ − mðd−s Þ� means that the uncertainty due to momentum scale, the dominant uncertainty in absolute-mass measurements, mostly cancels; however, it is still important to determine accurately the momenta of the final-state particles. the momentum-scale calibration of the spectrometer, which accounts for imperfect knowledge of the magnetic field and alignment, is discussed in detail in refs. [ , ]. the uncertainty on the calibrated momentum scale is estimated to be . % by comparing various particle masses measured at lhcb to their nominal values [ ]. the kinematic and vertex constraints used in the fits described previously reduce the statistical uncertainty on mðΛ bÞ − mðb̄ Þ by improving the resolution. these ] mass [mev/cs - d+cΛ ) c a n d id a te s / ( m e v /c lhcb - s d + cΛ→ bΛ - s d + cΣ→ bΛ -*s d + cΛ→ bΛ -π-k+ k+cΛ→ bΛ combinatorial ] mass [mev/c - d+cΛ ) c a n d id a te s / ( m e v /c - d+cΛ→ bΛ - d+cΣ + - d*+cΛ→ bΛ - sd + cΛ→ bΛ combinatorial lhcb - d+cΛ→ bΛ - d+cΣ + - d*+cΛ→ bΛ - sd + cΛ→ bΛ combinatorial fig. (color online). invariant mass distributions for (left) Λ b → Λ þ c d − s and (right) Λ b → Λ þ c d − candidates with the fits described in the text overlaid. table i. relative systematic uncertainties on branching fraction measurements (%). the production ratio σðb sÞ=σðb̄ Þ is taken from ref. [ ]. the numbers in parentheses in the last column are for the b s decay mode. source bðΛ b → Λþc d−Þ= bðΛ b → Λþc d−s Þ ð½bðΛ b → Λþc d−s Þ=bðb̄ → dþd−s Þ�Þ= ð½bðΛ b → Λþc π−Þ=bðb̄ → dþπ−Þ�Þ bðb s → dþd−s Þ= bðb̄ → dþd−s Þ bðb ðsÞ → Λþc Λ−c Þ= bðb ðsÞ → dþd−s Þ efficiency . . . . ( . ) fit model . . . � � � bðdþðsÞ; Λþc Þ . � � � � � � . σðb sÞ=σðb̄ Þ � � � � � � . � � � σðΛ bÞ=σðb̄ Þ � � � . � � � � � � total . . . . ( . ) prl , ( ) p h y s i c a l r e v i e w l e t t e r s week ending may - constraints also increase the systematic uncertainty by introducing a dependence on the precision of the nominal charm-hadron masses. these constraints are not imposed in the mass measurement, as it is found that this approach produces a smaller total uncertainty. the mass difference obtained is mðΛ bÞ − mðb̄ Þ ¼ . � . ðstatÞ � . ðsystÞ mev=c : the dominant systematic uncertainty (see table ii) arises due to a correlation between the reconstructed beauty- hadron mass and reconstructed charm-hadron flight dis- tance. the large difference in the Λþc and d þ hadron lifetimes [ ] could lead to only a partial cancellation of the biases induced by the charm-lifetime selection criteria. this effect is studied in simulation and a . mev=c uncer- tainty is assigned. the . % uncertainty in the momentum scale results in an uncertainty on the mass difference of . mev=c . many variations in the fit model are consid- ered, and none produce a significant shift in the mass difference. thesystematic uncertainty in themass difference due to the uncertainty in the amount of detector material in which charged particles lose energy is negligible [ ]. furthermore, the uncertainty on mðΛ bÞ − mðb̄ Þ due to differences in beauty-hadron production kinematics, as seen in fig. , is also found to be negligible. using the nominal value for mðb̄ Þ[ ] gives mðΛ bÞ ¼ . � . mev=c , where the uncertainty includes both statistical and systematic contributions. this is the most precise result to date. the total uncertainty is dominated by statistics and charm-hadron lifetime effects; thus, this result can be treated as being uncorrelated with the previous lhcb result obtained using the Λ b → j=ψΛ decay [ ]. a weighted average of the lhcb results gives mðΛ bÞ ¼ . � . mev=c . this value may then be used to improve the precision of the Ξ−b and Ω − b baryon masses using their mass differences with respect to the Λ b baryon, as reported in ref. [ ]. using bdt criteria optimized for maximizing the expected significance of b s → d þd−s , � b̄ and � b s decays are observed (see fig. ), from which the ratio extracted is bðb s → dþd−s Þ bðb̄ → dþd−s Þ ¼ . � . ðstatÞ � . ðsystÞ: this is the most precise measurement to date of bðb s → dþd−s Þ and supersedes ref. [ ]. since the two decay modes sharethesamefinal state,many systematic unc- ertainties cancel. the dominant contribution to the uncer- tainty comes from the beauty-hadron production fractions. ] mass [mev/cs - d+d ) c a n d id a te s / ( m e v /c lhcb s - d+ d→ b s - d+ d→s b - sd +* d→ b -* s d + d→ b -π-k+ k+ d→ b combinatorial ] mass [mev/cs - d+d ) c a n d id a te s / ( m e v /c lhcb s - d+ d→ b s - d+ d→s b - sd +* d→ b -* s d + d→ b -π-k+ k+ d→ b combinatorial fig. (color online). invariant mass distributions for dþd−s candidates selected using bdt criteria optimized for the (left) b̄ → dþd−s and (right) b s → d þd−s decay modes with the fits described in the text overlaid. [mev/c] t p ) s- d + d → b )/ n ( s- d + c Λ → b Λ n ( . . . . lhcb fig. (color online). efficiency-corrected ratio of the yields of Λ b → Λ þ c d − s and b̄ → dþd−s vs pt. the points are located at the mean pt value of the Λ b in each bin. the curve shows the data fit with the shape of the pt dependence measured in ref. [ ]. table ii. systematic uncertainties for mðΛ bÞ − mðb̄ Þ. description value (mev=c ) Λþc − dþ lifetime difference . momentum scale . fit model . total . prl , ( ) p h y s i c a l r e v i e w l e t t e r s week ending may - a small additional uncertainty on the efficiency arises due to theuncertaintyontheb s lifetime.uncertaintyinthefitmodel is largely due to the size of the combinatorial background neartheb s peak.themeasuredratioofbranchingfractionsis approximately the ratio of quark-mixing factors, as expected assuming nonfactorizable effects are small. a search is also performed for the decay modes b ðsÞ → Λ þ c Λ − c . regions centered around the nominal b ðsÞ meson masses with boundaries defined such that each region contains % of the corresponding signal are determined using simulation. the expected background contribution in each of these regions is obtained from the charm-hadron mass sidebands. applying this technique to the b̄ → dþd−s and Λ b → Λ þ c d − ðsÞ decays produces back- ground estimates consistent with those obtained by fitting the invariant mass spectra for those modes. the number of observed candidates in each signal region is then compared to the expected background contribution; no significant excess is observed in either Λþc Λ − c signal region. the limits obtained using the method of ref. [ ] and the known d−s [ ], d− [ ], and Λþc [ ] hadron branching fractions are bðb̄ → Λþc Λ−c Þ bðb̄ → dþd−s Þ < . ½ % c.l.�; bðb s → Λþc Λ−c Þ bðb s → dþd−s Þ < . ½ % c.l.�: for these results the lifetime of the light-mass b s eigenstate is assumed, as this produces the most conservative limits [ ]. this is the best limit to date for the b̄ decay mode and the first limit for the b s decay mode. in summary, first observations and relative branching- fraction measurements have been made for the decays Λ b → Λ þ c d − ðsÞ. the most precise measurements of the Λ b baryon mass and of bðb s → dþd−s Þ have been presented and the most stringent upper limits have been placed on bðb ðsÞ → Λþc Λ−c Þ. using bðb̄ → dþd−s Þ ¼ ð . � . Þ × − [ ] and bðΛ b → Λþc π−Þ=bðb̄ → dþπ−Þ from ref. [ ], the absolute branching fractions obtained are bðΛ b → Λþc d−s Þ ¼ ð . � . Þ × − ; bðΛ b → Λþc d−Þ ¼ ð . � . Þ × − ; bðb s → dþd−s Þ ¼ ð . � . Þ × − ; bðb̄ → Λþc Λ−c Þ < . × − ½ % c.l.�; bðb s → Λþc Λ−c Þ < . × − ½ % c:l:�: these results are all consistent with expectations that assume small nonfactorizable effects. we express our gratitude to our colleagues in the cern accelerator departments for the excellent performance of the lhc. we thank the technical and administrative staff at the lhcb institutes. we acknowledge support from cern and from the national agencies: capes, cnpq, faperj, and finep (brazil); nsfc (china); cnrs/in p and region auvergne (france); bmbf, dfg, hgf, and mpg (germany); sfi (ireland); infn (italy); fom and nwo (the netherlands); scsr (poland); men/ifa (romania); mines, rosatom, rfbr, and nrc “kurchatov institute” (russia); mineco, xuntagal, and gencat (spain); snsf and ser (switzerland); nas ukraine (ukraine); stfc (united kingdom); nsf (usa). we also acknowl- edge the support received from eplanet and the erc under fp . the tier computing centers are supported by in p (france), kit and bmbf (germany), infn (italy), nwo and surf (the netherlands), pic (spain), gridpp (united kingdom). we are indebted to the communities behind the multiple open-source software packages we depend on. we are also thankful for the computing resources and the access to software r&d tools provided by yandex llc (russia). 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theoretical and experimental physics (itep), moscow, russia institute of nuclear physics, moscow state university (sinp msu), moscow, russia institute for nuclear research of the russian academy of sciences (inr ran), moscow, russia budker institute of nuclear physics (sb ras) and novosibirsk state university, novosibirsk, russia institute for high energy physics (ihep), protvino, russia universitat de barcelona, barcelona, spain universidad de santiago de compostela, santiago de compostela, spain european organization for nuclear research (cern), geneva, switzerland ecole polytechnique fédérale de lausanne (epfl), lausanne, switzerland physik-institut, universität zürich, zürich, switzerland nikhef national institute for subatomic physics, amsterdam, the netherlands nikhef national institute for subatomic physics and vu university amsterdam, amsterdam, the netherlands nsc kharkiv institute of physics and technology (nsc kipt), kharkiv, ukraine institute for nuclear research of the national academy of sciences (kinr), kyiv, ukraine university of birmingham, birmingham, united kingdom h.h. wills physics laboratory, university of bristol, bristol, united kingdom cavendish laboratory, university of cambridge, cambridge, united kingdom department of physics, university of warwick, coventry, united kingdom stfc rutherford appleton laboratory, didcot, united kingdom prl , ( ) p h y s i c a l r e v i e w l e t t e r s week ending may - school of physics and astronomy, university of edinburgh, edinburgh, united kingdom school of physics and astronomy, university of glasgow, glasgow, united kingdom oliver lodge laboratory, university of liverpool, liverpool, united kingdom imperial college london, london, united kingdom school of physics and astronomy, university of manchester, manchester, united kingdom department of physics, university of oxford, oxford, united kingdom massachusetts institute of technology, cambridge, massachusetts, usa university of cincinnati, cincinnati, ohio, usa university of maryland, college park, maryland, usa syracuse university, syracuse, new york, usa pontifícia universidade católica do rio de janeiro (puc-rio), rio de janeiro, brazil (associated with universidade federal do rio de janeiro (ufrj), rio de janeiro, brazil) institute of particle physics, central china normal university, wuhan, hubei, china (associated with center for high energy physics, tsinghua university, beijing, china) institut für physik, universität rostock, rostock, germany (associated with physikalisches institut, ruprecht-karls-universität heidelberg, heidelberg, germany) national research centre kurchatov institute, moscow, russia (associated with institute of theoretical and experimental physics [itep], moscow, russia) instituto de fisica corpuscular (ific), universitat de valencia-csic, valencia, spain (associated with universitat de barcelona, barcelona, spain) kvi-university of groningen, groningen, the netherlands (associated with nikhef national institute for subatomic physics, amsterdam, the netherlands) celal bayar university, manisa, turkey (associated with european organization for nuclear research [cern], geneva, switzerland) aalso at politecnico di milano, milano, italy. balso at università di firenze, firenze, italy. calso at università di ferrara, ferrara, italy. dalso at università della basilicata, potenza, italy. ealso at università di modena e reggio emilia, modena, italy. falso at università di padova, padova, italy. galso at università di milano bicocca, milano, italy. halso at lifaels, la salle, universitat ramon llull, barcelona, spain. ialso at università di bologna, bologna, italy. jalso at università di roma tor vergata, roma, italy. kalso at università di genova, genova, italy. lalso at universidade federal do triângulo mineiro (uftm), uberaba-mg, brazil. malso at università di cagliari, cagliari, italy. nalso at scuola normale superiore, pisa, italy. oalso at hanoi university of science, hanoi, viet nam. palso at università di bari, bari, italy. qalso at università degli studi di milano, milano, italy. ralso at università di pisa, pisa, italy. salso at università di roma la sapienza, roma, italy. talso at università di urbino, urbino, italy. ualso at p.n. lebedev physical institute, russian academy of science (lpi ras), moscow, russia. prl , ( ) p h y s i c a l r e v i e w l e t t e r s week ending may - . n&v mh mathematics a beauty and a beast hermann nicolai the mapping of the largest exceptional lie group, e , is a milestone for enthusiasts for the aesthetics of mathematics. but this embodiment of complex symmetry could be of interest to fundamental physics, too. symmetry and beauty are often interlinked. this is so not only in art and music — one need only think of the intricate symmetry of a bach fugue — but also in mathemat- ics and, at its most fundamental level, physics. in a recent breakthrough , , which involved researchers and was four years in the making, mathematicians have mapped out one of the most mysteri- ous and fascinating of all mathematical objects: the ‘exceptional lie group’ e . in view of the magnitude of the computation and the sheer amount of data involved, the achievement has been lik- ened to the mapping of the human genome . but seeing the beauty in this complex beast can be hard: certainly more difficult than apprecia- ting a bach fugue without know ing the rules of counterpoint. in mathematics, symmetries are usually associated with operations that leave a geometrical object invariant. a sphere, for instance, remains the same under continuous rotations in space. the col- lection of such operations forms a mathemati- cal ‘group’. the mathematical description of continuous symmetries (as opposed to discrete symmetries, such as those that leave a crystal lattice invariant) is codified in the notion of a lie group, named after the norwegian math- ematician sophus lie. finite-dimensional lie groups were classified more than a century ago, by wilhelm killing and elie cartan, by dint of considering only group elements infini- tesimally close to identity: that is, to ‘rotations’ by arbitrarily small angles. simply put , they identified four infinite series of such groups, labelled an, bn, cn and dn for n = , , …, which essentially correspond to linear transfor- mations in spaces of arbitrary dimension that leave certain quadratic expressions invariant. there are also five exceptional groups that do not fit into these categories, designated g , f , e , e and e . visualizing rotations in three-dimensional a m . i n st . m a t h ./ p. m c m u ll en /j . s t em b r id g e space is straightforward (as it is, with some training in mathematics, in higher dimen- sions!), but the ‘visualization’ of exceptional symmetries and their action on geometrical objects is much harder. the results of such attempts are often collectively (and jokingly) referred to as the ‘botany’ of these lie groups. for instance g , by far the ‘easiest’ of the excep- tional groups, can be defined as the group that leaves invariant the multiplication table of a system of hypercomplex numbers known as octonions. e stands out as the largest and most difficult of the exceptional lie groups. it has dimensions, and its smallest non-trivial realization requires a space of dimensions , (see ref. for a physicist’s description of this object). in short, e is as intricate as symmetry can get. pictured here is a two-dimensional projection of e ’s ‘root system’ — a lattice-like system in eight dimensions that embodies its full complexity. like other lie groups, e comes in different versions, called real forms. roughly speaking, these differ according to whether ‘rotations’ are performed with a real-number angle or an imaginary-number ang le. more sp ecif i- cally, if it is possible to return to the starting point after a finite rota- tion, one speaks of a compact realization. a simple example is rotation in space by °, which can be rep- resented mathematically through multiplication by eiα with the (real) angle α = π. a simple non-com- pact transformation would be translation along a line, which is realized mathemati- cally as multiplication by eα. this is equivalent to rotation by an imaginary angle –iα: because i = – , then ei(–iα) = eα. e admits three real forms, one compact and two non-compact. quite generally, the non-compact forms are much more tricky to deal with. this makes the main advance just reported so impressive: it concerns the most subtle of all non-compact forms in lie-group theory, the ‘split-real form’ of e , sometimes denoted e ( ). aside from pure mathematics, what is the wider significance of this achievement? one answer lies in fundamental physics. sym metry concepts played a central role in the establish- ment of the two most successful theories of modern physics: general relativity, and quan- tum-field theory as embodied in particle physics’ standard model. in general relativ- ity, symmetry enters through the principle of general covariance: that the laws of physics should not depend on the coordinate system in which they are formulated. this principle enabled albert einstein to formulate in one news & views vol | may �� stroke the equations of the gravitational field governing the evolution of the universe, as well as many other phenomena that would other- wise be intractable (the interaction of light with gravity, for instance). in the standard model, symmetry is embod- ied by the principle of gauge invariance, which determines the way in which elementary par- ticles can interact. given this principle, and the apparatus of modern quantum-field theory, all that is needed to properly formulate the standard model is the specification of the sym- metry group, the matter-particle content, and the transformation properties of these matter fields (quarks and leptons) under the chosen symmetry group. gauge invariance automati- cally ensures the mathematical consistency (‘renormalizability’) of the theory, allowing us to extract definite predictions from seem- ingly infinite expressions, and thus making the standard model one of the best-tested theories of physics. yet in spite of their success, neither general relativity nor the standard model can be final theories of physics . this is first of all because of a basic incompatibility between the two theories, reflected in the appearance of ‘non- renormalizable’ infinities when einstein’s theory is quantized following the standard rules of quantum mechanics. equally importantly, neither theory is able to answer some obvious questions. for instance, what sets the pattern of elementary particles found in nature apart from other possible such patterns? similarly, what is so special about the standard model’s symmetry group, denoted su( ) × su( ) × u( ), which seems mathematically undistinguished? and, connected to those questions, how did the uni- verse, and with it space-time and matter, come into being at the moment of the big bang? to avoid the existing mathematical dis- crepancies, the yet-to-be-constructed unified theory (sometimes dubbed ‘m theory’) must be tightly constrained, and possibly even uniquely determined, by symmetry principles. one important difference between einstein’s theory of gravity and the standard model concerns the way in which symmetries are realized. in gen- eral relativity, symmetries act in physical space and time, whereas the gauge transformations of particle physics act in an abstract internal space (in which one can, for example, ‘rotate’ a proton into a neutron and vice versa). an important step on the long road to a unified theory was the development of super- symmetry, a new kind of symmetry relating the particle groups known as bosons and fermions . this led to supergravity, an extension of einstein’s theory, and superstring theory , which is considered by many to be the lead- ing contender to unify physics. surprisingly, it turned out that the ‘most supersymmetric’ extension of einstein’s theory — supergravity in space-time dimensions , — has the split- real forms of e , e and e automatically built into it , albeit in a rather hidden form. this seminal discovery was all the more remarkable because it revealed completely unsuspected connections. who could have anticipated what is, in effect, a link between the esoterics of exceptional lie groups and the absence of long-range (tensor) forces other than gravity in nature? more recent studies of gauged maximal supergravity theories in three dimensions have confirmed the intimate links between supergravity and the split-real form e ( ). as yet, we have no idea what the true extent of e ’s involvement in the scheme of things will be. if proponents of superstring theory are right, the compact form of e could be real- ized as a gauge symmetry in the framework of ‘grand unification’. but it is equally possible that e will be realized in a different and more subtle way, intertwining space-time and matter, and possibly involving the split-real form, rather than the compact form. the ambitious search for a fundamental sym- metry of nature might even force us to venture into the unknown territory of infinite-dimen- sional exceptional symmetry groups, of which the finite-dimensional e is just a subset. the prime candidate is e , about which we know next to nothing, other than that it exists. physi- cists should not let themselves get carried away by these intriguing possibilities, as experiment remains the final arbiter. but they would be well advised to take note of the exciting develop- ments in deciphering the e group. ■ hermann nicolai is at the max-planck-institut für gravitationsphysik (albert-einstein-institut), mühlenberg , d- potsdam, germany. e-mail: nicolai@aei.mpg.de . www.liegroups.org . http://aimath.org/e . bourbaki, n. eléments de mathématiques: groupes et algèbres de lie: chapitre (masson, paris, ). . günaydin, m., koepsell, k. & nicolai, h. comm. math. phys. , – ( ). . ramond, p. journeys beyond the standard model (perseus, new york, ). . bagger, j. & wess, j. supersymmetry and supergravity (princeton univ. press, ). . green, m. b., schwarz, j. h. & witten, e. superstring theory (cambridge univ. press, ). . nahm, w. nucl. phys. b , – ( ). . cremmer, e., julia, b. & scherk, j. phys. lett. b , – ( ). . cremmer, e. & julia, b. nucl. phys. b , – ( ). . nicolai, h. & samtleben, h. j. high energy phys. : ( ). chemical biology ignore the nonsense anton schmitz and michael famulok a small molecule forces the protein-translation machinery to overlook the signals that would otherwise result in its premature termination. genuine stop signs are, however, read and obeyed. several inherited diseases are caused by mutations in single nucleotides within genes. these mutations can transform the products of messenger rna codons, the sets of three nucleotides that determine which amino acid is incorporated into the growing pro- tein chain. when such ‘nonsense’ mutations are transcribed into a ‘stop’ codon, the cel- lular machinery that translates mrna into protein misinterprets the codon as a signal to terminate protein synthesis. these false stop codons are known as premature termination codons (ptcs) and result in the formation of truncated proteins that cannot function prop- erly and may even damage the cell, eventually leading to disease. depending on the disorder, nonsense mutations account for – % of cases of genetic disorders, including cystic fibrosis, muscular dystrophy and several types of cancer. on page of this issue, welch et al. report that a small organic molecule known as ptc can force the translation machinery to ignore ptcs, without preventing it from reading the real stop signals*. it has been known for the past years that the antibiotic gentamycin can prompt ribosomes — the core component of the cellu- lar protein-synthesis machinery — to read through ptcs, thereby generating full-length proteins . nevertheless, the clinical benefit of gentamycin is limited, because to be effective it has to be used at very high concentrations, which are associated with severe side effects. there is now hope that ptc , which, like gentamycin, ignores ptcs but lacks its adverse side effects, could be more beneficial in the clinic. indeed, interim results of phase ii clinical trials indicate that patients with ptc- induced forms of cystic fibrosis and duchenne muscular dystrophy might benefit from treat- ment with ptc — a promising result that has been commented on for some time , . welch et al. describe an astonishing feature of ptc — its selectivity for ptcs. why is this so striking? all organisms with mem- brane-bound cell nuclei (eukaryotes) have evolved mechanisms to protect themselves from the harmful products of nonsense muta- tions. there are two lines of defence. the first relies on the fast and efficient degradation of the truncated proteins after the transla- tion of ptc-containing mrnas. the second acts before these proteins are synthesized. this quality-control mechanism, known as *this article and the paper concerned were published online on april . nature|vol | may n e ws & v i e ws �� << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (none) /calrgbprofile (srgb iec - . ) /calcmykprofile (u.s. web coated \ swop\ v ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /default /detectblends true /colorconversionstrategy /leavecolorunchanged /dothumbnails false /embedallfonts true /embedjoboptions true /dscreportinglevel /syntheticboldness . /emitdscwarnings false /endpage - /imagememory /lockdistillerparams true /maxsubsetpct /optimize false /opm /parsedsccomments true 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/description << /jpn /deu /fra /ptb /dan /nld /esp /suo /ita /nor /sve /enu >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice european organization for nuclear research (cern) cern-ph-ep- - lhcb-paper- - september , study of w boson production in association with beauty and charm the lhcb collaboration† abstract the associated production of a w boson with a jet originating from either a light parton or heavy-flavor quark is studied in the forward region using proton-proton collisions. the analysis uses data corresponding to integrated luminosities of . and . fb− collected with the lhcb detector at center-of-mass energies of and tev, respectively. the w bosons are reconstructed using the w → µν decay and muons with a transverse momentum, pt, larger than gev in the pseudorapidity range . < η < . . the partons are reconstructed as jets with pt > gev and . < η < . . the sum of the muon and jet momenta must satisfy pt > gev. the fraction of w +jet events that originate from beauty and charm quarks is measured, along with the charge asymmetries of the w +b and w +c production cross sections. the ratio of the w+jet to z+jet production cross sections is also measured using the z → µµ decay. all results are in agreement with standard model predictions. phys. rev. d. ( ) c© cern on behalf of the lhcb collaboration, license cc-by- . . †authors are listed at the end of this article. ar x iv : . v [ he p- ex ] s ep http://creativecommons.org/licenses/by/ . / ii introduction measurements of w+jet production in hadron collisions provide important tests of the standard model (sm), especially of perturbative quantum chromodynamics (qcd) in the presence of heavy-flavor quarks. such measurements are also sensitive probes of the parton distribution functions (pdfs) of the proton. the ratio of the w +jet to z+jet production cross sections is a test of perturbative qcd methods and constrains the light-parton pdfs of the proton. the jet produced in association with the w boson may originate either from a b quark (w +b), c quark (w +c) or light parton. several processes contribute to the w +b and w +c final states at next-to-leading order (nlo) in perturbative qcd. the dominant mechanism for w +c production is gs → wc, but there are also important contributions from gs → wcg, gg → wcs̄, and qq̄ → wcc̄ [ ]. therefore, measuring the ratio of the w +c to w+jet production cross sections in the forward region at the lhc provides important constraints on the s quark pdf [ , ] at momentum transfers of q ≈ gev (c = throughout this article) and momentum fractions down to x ≈ − . previous measurements of the proton s quark pdf were primarily based on deep inelastic scattering experiments with q ≈ gev and x values o( . ) [ – ]. the w +c cross section has been measured at the tevatron [ , ] and at the lhc [ , ] in the central region. in the so-called four-flavor scheme, theoretical calculations are performed considering only the four lightest quarks in the proton [ ]. production of w+b proceeds via qq̄ → wg with g → bb̄ at leading order. if the b quark content of the proton is considered, i.e. the five-flavor scheme, then single-b production via qb → wbq also contributes [ ]. the ratio of the w +b to w+jet cross sections thus places constraints both on the intrinsic b quark content of the proton and the probability of gluon splitting into bb̄ pairs. the w +b cross section has been measured in the central region at the tevatron [ , ] and at the lhc [ ]. lhcb has measured the cross sections for inclusive w and z production in proton- proton (pp) collisions at center-of-mass energy √ s = tev [ – ], providing precision tests of the sm in the forward region. additionally, measurements of the z+jet and z+b cross sections have been made [ , ]. in this article, the associated production of a w boson with a jet originating from either a light parton or a heavy-flavor quark is studied using pp collisions at center-of-mass energies of and tev. the production of the w +b final state via top quark decay is not included in the signal definition in this analysis, but is reported separately in ref. [ ]. a comprehensive approach is taken, where the inclusive w+jet, w +b and w +c contributions are measured simultaneously, rather than split across multiple measurements as in refs. [ , , , – ]. the identification of c jets, in conjunction with b jets, is performed using the tagging algorithm described in ref. [ ], which improves upon previous c-tagging methods where muons or exclusive decays were required to identify the jet [ , ]. for each center-of-mass energy, the following production cross section ratios are measured: σ(wb)/σ(wj), σ(wc)/σ(wj), σ(w+j)/σ(zj), σ(w−j)/σ(zj), a(wb), and a(wc), where a(wq) ≡ σ(w+q) −σ(w−q) σ(w+q) + σ(w−q) . ( ) the analysis is performed using the w → µν decay and jets clustered with the anti-kt algorithm [ ] using a distance parameter r = . . the following fiducial requirements are applied: both the muon and the jet must have momentum transverse to the beam, pt, greater than gev; the pseudorapidity of the muon must fall within . < η(µ) < . ; the jet pseudorapidity must satisfy . < η(j) < . ; the muon and jet must be separated by ∆r(µ,j) > . , where ∆r ≡ √ ∆η + ∆φ and ∆η(∆φ) is the difference in pseudorapidity (azimuthal angle) between the muon and jet momenta; and the transverse component of the sum of the muon and jet momenta must satisfy pt(µ + j) ≡ (~p(µ) + ~p(j))t > gev. all results reported in this article are for within this fiducial region, i.e. no extrapolation outside of this region is performed. the article is organized as follows: the detector, data sample and simulation are described in sect. ; the event selection is given in sect. ; the signal yields are determined in sect. ; the systematic uncertainties are outlined in sect. ; and the results are presented in sect. . the lhcb detector and data set the lhcb detector [ , ] is a single-arm forward spectrometer covering the pseudorapidity range < η < , designed for the study of particles containing b or c quarks. the detector includes a high-precision tracking system consisting of a silicon-strip vertex detector surrounding the pp interaction region [ ], a large-area silicon-strip detector located upstream of a dipole magnet with a bending power of about tm, and three stations of silicon-strip detectors and straw drift tubes [ ] placed downstream of the magnet. the tracking system provides a measurement of momentum, p, of charged particles with a relative uncertainty that varies from . % at low momentum to . % at gev. the minimum distance of a track to a primary vertex, the impact parameter, is measured with a resolution of ( + /pt) µm, with pt in gev. different types of charged hadrons are distinguished using information from two ring-imaging cherenkov detectors. photons, electrons and hadrons are identified by a calorimeter system consisting of scintillating-pad and preshower detectors, an electromagnetic calorimeter and a hadronic calorimeter. the electromagnetic and hadronic calorimeters have energy resolutions of σ(e)/e = %/ √ e ⊕ % and σ(e)/e = %/ √ e ⊕ % (with e in gev), respectively. muons are identified by a system composed of alternating layers of iron and multiwire proportional chambers [ ]. the trigger [ ] consists of a hardware stage, based on information from the calorimeter and muon systems, followed by a software stage, which applies a full event reconstruction. this analysis requires at least one muon candidate that satisfies the trigger requirement of pt > gev. global event cuts (gecs), which prevent high-occupancy events from dominating the processing time of the software trigger, are also applied and have an efficiency of about % for w+jet and z+jet events. two sets of pp collision data collected with the lhcb detector are used: data collected during at √ s = tev, corresponding to an integrated luminosity of . fb− , and data collected during at √ s = tev, corresponding to an integrated luminosity of . fb− . simulated pp collisions, used to study the detector response, to define the event selection and to validate data-driven techniques, are generated using pythia [ ] with an lhcb configuration [ ]. decays of hadronic particles are described by evtgen [ ] in which final-state radiation (fsr) is generated using photos [ ]. the interaction of the generated particles with the detector, and its response, are implemented using the geant toolkit [ ] as described in ref. [ ]. results are compared with theoretical calculations at nlo using mcfm [ ] and the ct pdf set [ ]. the theoretical uncertainty is a combination of pdf, scale, and strong-coupling (αs) uncertainties. the pdf and scale uncertainties are evaluated following refs. [ ] and [ ], respectively. the αs uncertainty is evaluated as the envelope obtained using αs(mz) ∈ [ . , . , . ] in the theory calculations. event selection the signature for w +jet events is an isolated high-pt muon and a well-separated jet, both produced in the same pp interaction. muon candidates are identified with tracks that have associated hits in the muon system. the muon candidate must have pt(µ) > gev and pseudorapidity within . < η(µ) < . . background muons from w → τ → µ decays or semileptonic decays of heavy-flavor hadrons are suppressed by requiring the muon impact parameter to be less than . mm [ ]. background from high-momentum kaons and pions that enter the muon system and are misidentified as muons, is reduced by requiring that the sum of the energy of the associated electromagnetic and hadronic calorimeter deposits does not exceed % of the momentum of the muon candidate. jets are clustered using the anti-kt algorithm with a distance parameter r = . , as implemented in fastjet [ ]. information from all the detector subsystems is used to create charged and neutral particle inputs to the jet-clustering algorithm using a particle flow approach [ ]. during and , lhcb collected data with a mean number of pp collisions per beam crossing of about . . to reduce contamination from multiple pp interactions, charged particles reconstructed within the vertex detector may only be clustered into a jet if they are associated with the same pp collision. signal events are selected by requiring a muon candidate and at least one jet with ∆r(µ,j) > . . for each event the highest-pt muon candidate that satisfies the trigger requirements is selected, along with the highest-pt jet from the same pp collision. the high-pt muon candidate is not removed from the anti-kt inputs and so is clustered into a jet. this jet, referred to as the muon jet and denoted as jµ, is used to discriminate between w +jet and dijet events. the requirement pt(jµ +j) > gev is made to suppress dijet backgrounds, which are well balanced in pt, unlike w+jet events where there is undetected energy from the neutrino. furthermore, the distribution of the fractional muon candidate pt within the muon jet, pt(µ)/pt(jµ), is used to separate vector bosons from jets. for vector-boson production, this ratio deviates from unity only due to muon fsr, activity from the underlying event, or from neutral-particle production in a separate pp collision, whereas for jet production this ratio is driven to smaller values by the presence of additional radiation produced in association with the muon candidate. events with a second, oppositely charged, muon candidate from the same pp collision are vetoed. however, when the dimuon invariant mass is in the range < m(µ+µ−) < gev, such events are selected as z+jet candidates and the pt(jµ +j) requirement is not applied. two z+jet data samples are selected at each center-of-mass energy: a data sample where only the µ+ is required to satisfy the trigger requirements and one where only the µ− is required to satisfy them. the first sample is used to measure σ(w+j)/σ(zj), while the second is used for σ(w−j)/σ(zj). this strategy leads to approximate cancellation of the uncertainty in the trigger efficiency in the measurement of these ratios. the reconstructed jets must have pt(j) > gev and . < η(j) < . . the reduced η(j) acceptance ensures nearly uniform jet reconstruction and heavy-flavor tagging efficien- cies. the momentum of a reconstructed jet is scaled to obtain an unbiased estimate of the true jet momentum. the scaling factor, typically between . and . , is determined from simulation and depends on the jet pt and η, the fraction of the jet transverse momentum measured with the tracking systems, and the number of pp interactions in the event. no scaling is applied to the momentum of the muon jet. migration of events in and out of the jet pt fiducial region due to the detector response is corrected for by an unfolding technique. data-driven methods are used to obtain the unfolding matrix, with the resulting corrections to the measurements presented in this article being at the percent level. the jets are identified, or tagged, as originating from the hadronization of a heavy-flavor quark by the presence of a secondary vertex (sv) with ∆r < . between the jet axis and the sv direction of flight, defined by the vector from the pp interaction point to the sv position. two boosted decision trees (bdts) [ , ], bdt(bc|udsg) and bdt(b|c), trained on the characteristics of the sv and the jet, are used to separate heavy-flavor jets from light-parton jets, and to separate b jets from c jets. the two-dimensional distribution of the bdt response observed in data is fitted to obtain the sv-tagged b, c and light-parton jet yields. the sv-tagger algorithm is detailed in ref. [ ], where the heavy-flavor tagging efficiencies and light-parton mistag probabilities are measured in data. background determination contributions from six processes are considered in the w +jet data sample: w +jet signal events; z+jet events where one muon is not reconstructed; top quark events producing a w+jet final state; z → ττ events where one τ lepton decays to a muon and the other decays hadronically; qcd dijet events; and vector boson pair production. simulations based on nlo predictions show that the last contribution is negligible. the signal yields are obtained for each muon charge and center-of-mass energy in- dependently. the pt(µ)/pt(jµ) distribution is fitted to determine the w+jet yield of each data sample. to determine the w +b and w +c yields, the subset of candidates with an sv-tagged jet is binned according to pt(µ)/pt(jµ). in each pt(µ)/pt(jµ) bin, the two-dimensional sv-tagger bdt-response distributions are fitted to determine the yields of b-tagged and c-tagged jets, which are used to form the pt(µ)/pt(jµ) distributions for candidates with b-tagged and c-tagged jets. these pt(µ)/pt(jµ) distributions are fitted to determine the sv-tagged w +b and w +c yields. finally, to obtain σ(wb)/σ(wj) and σ(wc)/σ(wj), the jet-tagging efficiencies of �tag(b) ≈ % and �tag(c) ≈ % are accounted for. in all fits performed in this analysis, the templates are histograms with fixed shapes. the pt(µ)/pt(jµ) distributions are shown in fig. (in this and subsequent figures the pull represents the difference between the data and the fit, in units of standard deviations). the w boson yields are determined by performing binned extended-maximum-likelihood fits to these distributions with the following components: • the w boson template is obtained by correcting the pt(µ)/pt(jµ) distribution observed in z+jet events for small differences between w and z decays derived from simulation. • the template for z boson events where one muon is not reconstructed is obtained by correcting, using simulation, the pt(µ)/pt(jµ) distribution observed in fully reconstructed z+jet events for small differences expected in partially reconstructed z+jet events. the yield is fixed from the fully reconstructed z+jet data sample, where simulation is used to obtain the probability that the muon is missed, either because it is out of acceptance or it is not reconstructed. • the templates for b, c and light-parton jets are obtained using dijet-enriched data samples. these samples require pt(jµ+j) < gev and, for the heavy-flavor samples, either a stringent b-tag or c-tag requirement on the associated jet. the templates are corrected for differences in the pt(jµ) spectra between the dijet-enriched and signal regions. the contributions of b, c and light-parton jets are each free to vary in the pt(µ)/pt(jµ) fits. the pt(µ)/pt(jµ) fits determine the w+jet yields, which include contributions from top quark and z → ττ production. the top quark and z → ττ contributions cannot be separated from w+jet since their pt(µ)/pt(jµ) distributions are nearly identical to that of w+jet events. the subtraction of these backgrounds is described below. the yields of events with w bosons associated with b-tagged and c-tagged jets are obtained by fitting the two-dimensional sv-tagger bdt-response distributions for √ s = and tev and for each muon charge separately in bins of pt(µ)/pt(jµ). the sv-tagger bdt templates used in this analysis are obtained from the data samples enriched in b and c jets used in ref. [ ]. as a consistency check, the two-dimensional bdt distributions are fitted using templates from simulation; the yields shift only by a few percent. figure shows the bdt distributions combining all data in the most sensitive region, w +jet events with pt(µ)/pt(jµ) > . . this is the region where the muon carries a large fraction of the muon-jet momentum and is, therefore, highly isolated. figure shows the distributions in . . . . . c an di da te s/ . data w z jets = tevs, +µ ) µ j( t p)/µ( t p . . . . . ca n d id at es = tevs, −µ lhcb . . . . . p ul l - ) µ j( t p)/µ( t p . . . . . p ul l - . . . . . c an di da te s/ . data w z jets = tevs, +µ ) µ j( t p)/µ( t p . . . . . ca n d id at es = tevs, −µ lhcb . . . . . p ul l - ) µ j( t p)/µ( t p . . . . . p ul l - figure : distributions of pt(µ)/pt(jµ) with fits overlaid from (top) √ s = tev and (bottom) tev data for (left) µ+ and (right) µ−. a dijet dominated region ( . < pt(µ)/pt(jµ) < . ). in the dijet region the majority of sv-tagged jets associated with the high-pt muon candidate are found to be b jets. this is due to the large semileptonic branching fraction of b hadrons. in the w +jet signal region there are significant contributions from both b and c jets. as a consistency check, the b, c, and light-parton yields are obtained in the pt(µ)/pt(jµ) > . signal region from a fit using only two of the bdt inputs, both of which rely only on basic sv properties, the track multiplicity and the corrected mass, which is defined as mcor = √ m + |~p| sin θ + |~p|sin θ, ( ) where m and ~p are the invariant mass and momentum of the particles that form the sv, and θ is the angle between ~p and the flight direction. the corrected mass, which is the minimum mass for a long-lived hadron whose trajectory is consistent with the flight direction, peaks near the d meson mass for c jets and consequently provides excellent discrimination )udsg|bcbdt( - - . . )c| b b d t ( - - . . lhcb data )udsg|bcbdt( - - . . )c| b b d t ( - - . . lhcb fit )udsg|bcbdt( - - . . c an di da te s/ . lhcb data b c udsg )c|bbdt( - - . . c an di da te s/ . lhcb data b c udsg - - - )udsg|bcbdt( - - . . )c| b b d t ( - - . . lhcb pulls figure : (top left) two-dimensional sv-tag bdt distribution and (top right) fit for events in the subsample with pt(µ)/pt(jµ) > . , projected onto the (bottom left) bdt(bc|udsg) and (bottom right) bdt(b|c) axes. combined data for √ s = and tev for both muon charges are shown. against other jet types. the sv track multiplicity identifies b jets well, since b-hadron decays typically produce many displaced tracks. in fig. , the distributions of mcor and sv track multiplicity for a subsample of sv-tagged events with bdt(bc|udsg) > . (see fig. ) are fitted simultaneously. the templates used in these fits are obtained from data )udsg|bcbdt( - - . . )c| b b d t ( - - . . lhcb data )udsg|bcbdt( - - . . )c| b b d t ( - - . . lhcb fit )udsg|bcbdt( - - . . c an di da te s/ . lhcb data b c udsg )c|bbdt( - - . . c an di da te s/ . lhcb data b c udsg - - - )udsg|bcbdt( - - . . )c| b b d t ( - - . . lhcb pulls figure : (top left) two-dimensional sv-tag bdt distribution and (top right) fit for events in the subsample with . < pt(µ)/pt(jµ) < . , projected onto the (bottom left) bdt(bc|udsg) and (bottom right) bdt(b|c) axes. combined data for √ s = and tev for both muon charges are shown. in the same manner as the sv-tagger bdt templates. after correcting for the efficiency of requiring bdt(bc|udsg) > . , the b and c yields determined from the fits to mcor and sv track multiplicity and from the two-dimensional bdt fits are consistent. the mistag probability for w+light-parton events in this sample is found to be approximately . %, [gev]cormsv c an di da te s/ . g ev lhcb data b c udsg (tracks)nsv c an di da te s lhcb data b c udsg figure : projections of simultaneous fits of (left) mcor and (right) sv track multiplicity for the sv-tagged subsample with bdt(bc|udsg) > . and pt(µ)/pt(jµ) > . . the highest mcor bin includes candidates with mcor > gev. combined data for √ s = and tev for both muon charges are shown. which agrees with the value obtained from simulation. from the sv-tagger bdt fits, the b and c yields are obtained in bins of √ s, muon charge, and pt(µ)/pt(jµ). the pt(µ)/pt(jµ) distributions for muons associated with b-tagged and c-tagged jets are shown in figs. and . these distributions are fitted to determine the w +b and w +c final-state yields as in the inclusive w+jet sample. the z+b and z+c yields are obtained by fitting the sv-tagger bdt distributions in the fully reconstructed z+jet data samples and then correcting for the missed-muon probability. the fits are shown in figs. and for each muon charge and center-of-mass energy. the yields obtained still include contributions from top quark production and z → ττ. the z → ττ background, where one τ lepton decays into a muon and the other into a hadronic jet, contaminates the w +c sample due to the similarity of the c-hadron and τ lepton masses. the pt(sv)/pt(j) distribution, where pt(sv) is the transverse momentum of the particles that form the sv, is used to discriminate between c and τ jets, since svs produced from τ decays usually carry a larger fraction of the jet energy than svs from c-hadron decays. figure shows fits to the pt(sv)/pt(j) distributions observed in data where the b and light-parton yields are fixed using the results of bdt fits performed on the data samples. a requirement of bdt(bc|udsg) > . is applied to this sample to remove the majority of sv-tagged light-parton jets while retaining % of b, c and τ jets. the only free parameter in these fits is the fraction of jets identified as charm in the sv-tagger bdt fits that originate from τ leptons. the pt(sv)/pt(j) templates are obtained from simulation. the z → ττ yields are consistent with sm expectations and are about times smaller than the w +c yields. these results are extrapolated to the inclusive sample using simulation. the top quark background is determined in the dedicated analysis of ref. [ ], where a reduced fiducial region is used to enrich the relative top quark content. the yields . . . . . c an di da te s/ . = tevs, +µlhcb -jetb+µ ) µ j( t p)/µ( t p . . . . . ca n d id at es = tevs, −µ data w z jets . . . . . p ul l - ) µ j( t p)/µ( t p . . . . . p ul l - . . . . . c an di da te s/ . = tevs, +µlhcb -jetb+µ ) µ j( t p)/µ( t p . . . . . ca n d id at es = tevs, −µ data w z jets . . . . . p ul l - ) µ j( t p)/µ( t p . . . . . p ul l - figure : fits to pt(µ)/pt(jµ) distributions for b-tagged data samples for √ s = and tev. and charge asymmetries of the w +b final state as functions of pt(µ + b) are used to discriminate between w +b and top quark production. the results obtained in ref. [ ] are consistent with sm expectations and are extrapolated to the fiducial region of this analysis using simulation based on nlo calculations. the extrapolated top quark yields are subtracted from the observed number of w +b candidates to obtain the signal yields. top quark production is found to be responsible for about / of events that contain a w boson and b jet. a summary of all signal yields is given in table . systematic uncertainties a summary of the relative systematic uncertainties separated by source for each mea- surement is provided in table . a detailed description of each contribution is given below. the pt distributions of muons from w and z bosons produced in association with . . . . . c an di da te s/ . data w z jets = tevs, +µlhcb -jetc+µ ) µ j( t p)/µ( t p . . . . . ca n d id at es = tevs, −µ . . . . . p ul l - ) µ j( t p)/µ( t p . . . . . p ul l - . . . . . c an di da te s/ . data w z jets = tevs, +µlhcb -jetc+µ ) µ j( t p)/µ( t p . . . . . ca n d id at es = tevs, −µ . . . . . p ul l - ) µ j( t p)/µ( t p . . . . . p ul l - figure : fits to pt(µ)/pt(jµ) distributions for c-tagged data samples for √ s = and tev. b, c and light-parton jets are nearly identical. this results in a negligible uncertainty from muon trigger and reconstruction efficiency on cross section ratios involving only w bosons. in the ratios σ(w+j)/σ(zj) and σ(w−j)/σ(zj), the muon from the z boson decay with the same charge as that from the w decay is required to satisfy the same trigger and selection requirements as the w boson muon, giving negligible uncertainty from the trigger and selection efficiency. the efficiency for reconstructing and selecting the additional muon from the z boson decay is obtained from the data-driven studies of ref. [ ]. a further data-driven correction is applied to account for the higher occupancy in events with jets [ ]; a % systematic uncertainty is assigned to this correction. the gec efficiency is obtained following ref. [ ]: an alternative dimuon trigger requirement with a looser gec is used to determine the fraction of events that are rejected. the gec efficiencies for all final states are found to be consistent within a statistical precision of %, which is assigned as a systematic uncertainty. as a further check, the number of jets per event reconstructed in association with w or z bosons is compared and found to be consistent. (jet) t p(sv)/ t p . . . . c an di da te s/ . data b c udsg τ = tevslhcb (jet) t p(sv)/ t p . . . . c an di da te s/ . data b c udsg τ = tevslhcb (jet) t p(sv)/ t p . . . . p ul l - (jet) t p(sv)/ t p . . . . p ul l - figure : fits to the pt(sv)/pt(j) distributions in (left) tev and (right) tev data for candidates with pt(µ)/pt(jµ) > . and bdt(bc|udsg) > . . table : summary of signal yields. the two zj yields denote the charge of the muon on which the trigger requirement is made. the zj yields given are the numbers of candidates observed, while the w boson yields are obtained from fits. the yield due to top quark production is subtracted in these results. tev tev mode µ+ µ− µ+ µ− zj wj ± ± ± ± wb-tag ± ± ± ± wc-tag ± ± ± ± the jet reconstruction efficiencies for heavy-flavor and light-parton jets in simulation are found to be consistent within %, which is assigned as a systematic uncertainty for flavor-dependencies in the jet-reconstruction efficiency. the jet pt detector response is studied with a data sample enriched in b jets using sv tagging. the pt(sv)/pt(j) distribution observed in data is compared to templates obtained from simulation in bins of jet pt. the resolution and scale in simulation for each jet pt bin are varied to find the best description of the data and to construct a data-driven unfolding matrix. the results obtained using this unfolding matrix are consistent with those obtained using a matrix determined by studies of pt balance in z+jet events [ ], where no heavy-flavor tagging is applied. the unfolding corrections are at the percent level and their statistical precision is assigned as the uncertainty. the heavy-flavor tagging efficiencies are measured from data in ref. [ ], where a % uncertainty is assigned for b and c jets. the cross-check fits of sect. , using the corrected mass and track multiplicity, remove information associated with jet quantities, such as pt, from the yield determination and produce yields consistent at the % level. this is assigned as the uncertainty for the sv-tagged yield determination. the w boson template for the pt(µ)/pt(jµ) distribution is derived from data, as described in sect. . the fit is repeated using variations of this template, e.g. using a template taken directly from simulation and using separate templates for w+ and w−, to assess a systematic uncertainty. the dijet templates are obtained from data in a dijet-enriched region. the residual, small w boson contamination is subtracted using two methods: the w boson yield expected in the dijet-enriched region is taken from simulation; and the pt(µ)/pt(jµ) distribution in the dijet-enriched region is fitted to a parametric function to estimate the w boson yield. the difference in the w boson yields obtained using these two sets of dijet templates is at most %. the uncertainty on w/z ratios due to the w boson and dijet templates is %. the uncertainty due to the w boson template cancels to good approximation in the measurements of σ(wb)/σ(wj) and σ(wc)/σ(wj); however, the uncertainty due to the dijet templates is larger due to the enhanced dijet background levels. variations of the dijet templates are considered, with % and % uncertainties assigned on σ(wb)/σ(wj) and σ(wc)/σ(wj). the systematic uncertainty from top quark production is taken from ref. [ ], while the systematic uncertainty from z → ττ is evaluated by fitting the data using variations of the pt(sv)/pt(j) templates. all other electroweak backgrounds are found to be negligible from nlo predictions. all w → µν yields have a small contamination from w → τ → µ decays that cancels in all cross section ratios except for the w/z ratios. a scaling factor of . , obtained from simulation, is applied to the w boson yields. a % uncertainty is assigned to the scale factor, which is obtained from the difference between the correction factor from simulation and a data-driven study of this background [ ] for inclusive w → µν production. the trigger, reconstruction and selection requirements are consistent with being charge symmetric [ ], which results in negligible uncertainty on a(wb) and a(wc). unfolding of the jet pt detector response is performed independently for w + and w− bosons, with the statistical uncertainties on the corrections to the charge asymmetries assigned as systematic uncertainties. the uncertainty on the w +b and w +c yields from the bdt templates is included in the charge asymmetry uncertainty due to the fact that the fractional jet content of the sv-tagged samples is charge dependent. the uncertainty on the charge asymmetries due to determination of the w boson yields is evaluated using an alternative method for obtaining the charge asymmetries. the raw charge asymmetry in the b-jet and c-jet yields in the pt(µ)/pt(jµ) > . region is obtained from the sv-tagger bdt fits. the z+jet and dijet backgrounds are charge symmetric at the percent level and contribute at most to % of the events in this pt(µ)/pt(jµ) region. therefore, a(wb) and a(wc) are approximated by scaling the raw asymmetries by the inverse of the w boson purity in the pt(µ)/pt(jµ) > . region. a small correction must also be applied table : systematic uncertainties. relative uncertainties are given for cross section ratios and absolute uncertainties for charge asymmetries. source σ(wb) σ(wj) σ(wc) σ(wj) σ(wj) σ(zj) a(wb) a(wc) muon trigger and selection − − % − − gec % % % − − jet reconstruction % % − − − jet pt % % % . . (b,c)-tag efficiency % % − − sv-tag bdt templates % % . . pt(µ)/pt(jµ) templates % % % . . top quark % − − . z → ττ − % − − − other electroweak − − − − − w → τ → µ − − % − − total % % % . . table : summary of the results and sm predictions. for each measurement the first uncertainty is statistical, while the second is systematic. all results are reported within a fiducial region that requires a jet with pt > gev in the pseudorapidity range . < η < . , a muon with pt > gev in the pseudorapidity range . < η < . , pt(µ + j) > gev, and ∆r(µ,j) > . . for z+jet events both muons must fulfill the muon requirements and < m(µµ) < gev; the z+jet fiducial region does not require pt(µ + j) > gev. results sm prediction tev tev tev tev σ(wb) σ(wj) × . ± . ± . . ± . ± . . + . − . . + . − . σ(wc) σ(wj) × . ± . ± . . ± . ± . . + . − . . + . − . a(wb) . ± . ± . . ± . ± . . + . − . . + . − . a(wc) − . ± . ± . − . ± . ± . − . + . − . − . + . − . σ(w+j) σ(zj) . ± . ± . . ± . ± . . + . − . . + . − . σ(w−j) σ(zj) . ± . ± . . ± . ± . . + . − . . + . − . to a(wb) to account for top quark production. the difference between the asymmetries from this method and the nominal method is assigned as a systematic uncertainty from w boson signal determination. the uncertainty on a(wb) due to top quark production is taken from ref. [ ]. results the results for √ s = and tev are summarized in table . each result is compared to sm predictions calculated at nlo using mcfm [ ] and the ct pdf set [ ] as described in sect. . production of w+jet events in the forward region requires a large imbalance in x of the initial partons. in the four-flavor scheme at leading order, w +b production proceeds via qq̄ → wg(bb̄), where the charge of the w boson has the same sign as that of the initial parton with larger x. therefore, a(wb) ≈ + / is predicted due to the valence quark content of the proton. the dominant mechanism for w +c production is gs → wc, which is charge symmetric assuming symmetric s and s̄ quark pdfs. however, the cabibbo-suppressed contribution from gd → wc leads to a prediction of a small negative value for a(wc). the σ(wb)/σ(wj) ratio in conjunction with the w +b charge asymmetry is consistent with mcfm calculations performed in the four-flavor scheme, where w +b production is primarily from gluon splitting. this scheme assumes no intrinsic b quark content in the proton. the data do not support a large contribution from intrinsic b quark content in the proton but the precision is not sufficient to rule out such a contribution at o( %). the ratio [σ(wb) + σ(top)]/σ(wj) is measured to be . ± . (stat) ± . (syst)% at√ s = tev and . ± . (stat) ± . (syst)% at √ s = tev, which agree with the nlo sm predictions of . ± . % and . ± . %, respectively. the σ(wc)/σ(wj) ratio is much larger than σ(wb)/σ(wj), which is consistent with wc production from intrinsic s quark content of the proton. the measured charge asymmetry for w +c is about σ smaller than the predicted value obtained with ct , which assumes symmetric s and s̄ quark pdfs. this could suggest a larger than expected contribution from scattering off of strange quarks or a charge asymmetry between s and s̄ quarks in the proton. the ratio σ(w+j)/σ(zj) is consistent within σ with nlo predictions, while the observed σ(w−j)/σ(zj) ratio is higher than the predicted value by about . σ. acknowledgments we express our gratitude to our colleagues in the cern accelerator departments for the excellent performance of the lhc. we thank the technical and administrative staff at the lhcb institutes. we acknowledge support from cern and from the national agencies: capes, cnpq, faperj and finep (brazil); nsfc (china); cnrs/in p (france); bmbf, dfg, hgf and mpg (germany); infn (italy); fom and nwo (the netherlands); mnisw and ncn (poland); men/ifa (romania); mines and fano (russia); mineco (spain); snsf and ser (switzerland); nasu (ukraine); stfc (united kingdom); nsf (usa). the tier computing centres are supported by in p (france), kit and bmbf (germany), infn (italy), nwo and surf (the netherlands), pic (spain), gridpp (united kingdom). we are indebted to the communities behind the multiple open source software packages on which we depend. we are also thankful for the computing resources and the access to software r&d tools provided by yandex llc (russia). individual groups or members have received support from eplanet, marie sk lodowska-curie actions and erc (european union), conseil général de haute-savoie, labex enigmass and ocevu, région auvergne (france), rfbr (russia), xuntagal and gencat (spain), royal society and royal commission for the exhibition of (united kingdom). references [ ] w. j. stirling and e. vryonidou, charm production in association with an electroweak gauge boson at the lhc, phys. rev. lett. 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, o. steinkamp , o. stenyakin , f. sterpka , s. stevenson , s. stoica , s. stone , b. storaci , s. stracka ,t, m. straticiuc , u. straumann , l. sun , w. sutcliffe , k. swientek , s. swientek , v. syropoulos , m. szczekowski , p. szczypka , , t. szumlak , s. t’jampens , t. tekampe , m. teklishyn , g. tellarini ,f , f. teubert , c. thomas , e. thomas , j. van tilburg , v. tisserand , m. tobin , j. todd , s. tolk , l. tomassetti ,f , d. tonelli , s. topp-joergensen , n. torr , e. tournefier , s. tourneur , k. trabelsi , m.t. tran , m. tresch , a. trisovic , a. tsaregorodtsev , p. tsopelas , n. tuning , , a. ukleja , a. ustyuzhanin , , u. uwer , c. vacca ,e, v. vagnoni , g. valenti , a. vallier , r. vazquez gomez , p. vazquez regueiro , c. vázquez sierra , s. vecchi , j.j. velthuis , m. veltri ,h, g. veneziano , m. vesterinen , b. viaud , d. vieira , m. vieites diaz , x. vilasis-cardona ,p, a. vollhardt , d. volyanskyy , d. voong , a. vorobyev , v. vorobyev , c. voß , j.a. de vries , r. waldi , c. wallace , r. wallace , j. walsh , s. wandernoth , j. wang , d.r. ward , n.k. watson , d. websdale , a. weiden , m. whitehead , d. wiedner , g. wilkinson , , m. wilkinson , m. williams , m.p. williams , m. williams , t. williams , f.f. wilson , j. wimberley , j. wishahi , w. wislicki , m. witek , g. wormser , s.a. wotton , s. wright , k. wyllie , y. xie , z. xu , z. yang , j. yu , x. yuan , o. yushchenko , m. zangoli , m. zavertyaev ,b, l. zhang , y. zhang , a. zhelezov , a. zhokhov , l. zhong , s. zucchelli . centro brasileiro de pesquisas f́ısicas (cbpf), rio de janeiro, brazil universidade federal do rio de janeiro (ufrj), rio de janeiro, brazil center for high energy physics, tsinghua university, beijing, china lapp, université savoie mont-blanc, cnrs/in p , annecy-le-vieux, france clermont université, université blaise pascal, cnrs/in p , lpc, clermont-ferrand, france cppm, aix-marseille université, cnrs/in p , marseille, france lal, université paris-sud, cnrs/in p , orsay, france lpnhe, université pierre et marie curie, université paris diderot, cnrs/in p , paris, france fakultät physik, technische universität dortmund, dortmund, germany max-planck-institut für kernphysik (mpik), heidelberg, germany physikalisches institut, ruprecht-karls-universität heidelberg, heidelberg, germany school of physics, university college dublin, dublin, ireland sezione infn di bari, bari, italy sezione infn di bologna, bologna, italy sezione infn di cagliari, cagliari, italy sezione infn di ferrara, ferrara, italy sezione infn di firenze, firenze, italy laboratori nazionali dell’infn di frascati, frascati, italy sezione infn di genova, genova, italy sezione infn di milano bicocca, milano, italy sezione infn di milano, milano, italy sezione infn di padova, padova, italy sezione infn di pisa, pisa, italy sezione infn di roma tor vergata, roma, italy sezione infn di roma la sapienza, roma, italy henryk niewodniczanski institute of nuclear physics polish academy of sciences, kraków, poland agh - university of science and technology, faculty of physics and applied computer science, kraków, poland national center for nuclear research (ncbj), warsaw, poland horia hulubei national institute of physics and nuclear engineering, bucharest-magurele, romania petersburg nuclear physics institute (pnpi), gatchina, russia institute of theoretical and experimental physics (itep), moscow, russia institute of nuclear physics, moscow state university (sinp msu), moscow, russia institute for nuclear research of the russian academy of sciences (inr ran), moscow, russia budker institute of nuclear physics (sb ras) and novosibirsk state university, novosibirsk, russia institute for high energy physics (ihep), protvino, russia universitat de barcelona, barcelona, spain universidad de santiago de compostela, santiago de compostela, spain european organization for nuclear research (cern), geneva, switzerland ecole polytechnique fédérale de lausanne (epfl), lausanne, switzerland physik-institut, universität zürich, zürich, switzerland nikhef national institute for subatomic physics, amsterdam, the netherlands nikhef national institute for subatomic physics and vu university amsterdam, amsterdam, the netherlands nsc kharkiv institute of physics and technology (nsc kipt), kharkiv, ukraine institute for nuclear research of the national academy of sciences (kinr), kyiv, ukraine university of birmingham, birmingham, united kingdom h.h. wills physics laboratory, university of bristol, bristol, united kingdom cavendish laboratory, university of cambridge, cambridge, united kingdom department of physics, university of warwick, coventry, united kingdom stfc rutherford appleton laboratory, didcot, united kingdom school of physics and astronomy, university of edinburgh, edinburgh, united kingdom school of physics and astronomy, university of glasgow, glasgow, united kingdom oliver lodge laboratory, university of liverpool, liverpool, united kingdom imperial college london, london, united kingdom school of physics and astronomy, university of manchester, manchester, united kingdom department of physics, university of oxford, oxford, united kingdom massachusetts institute of technology, cambridge, ma, united states university of cincinnati, cincinnati, oh, united states university of maryland, college park, md, united states syracuse university, syracuse, ny, united states pontif́ıcia universidade católica do rio de janeiro (puc-rio), rio de janeiro, brazil, associated to institute of particle physics, central china normal university, wuhan, hubei, china, associated to departamento de fisica , universidad nacional de colombia, bogota, colombia, associated to institut für physik, universität rostock, rostock, germany, associated to national research centre kurchatov institute, moscow, russia, associated to yandex school of data analysis, moscow, russia, associated to instituto de fisica corpuscular (ific), universitat de valencia-csic, valencia, spain, associated to van swinderen institute, university of groningen, groningen, the netherlands, associated to auniversidade federal do triângulo mineiro (uftm), uberaba-mg, brazil bp.n. lebedev physical institute, russian academy of science (lpi ras), moscow, russia cuniversità di bari, bari, italy duniversità di bologna, bologna, italy euniversità di cagliari, cagliari, italy f università di ferrara, ferrara, italy guniversità di firenze, firenze, italy huniversità di urbino, urbino, italy iuniversità di modena e reggio emilia, modena, italy juniversità di genova, genova, italy kuniversità di milano bicocca, milano, italy luniversità di roma tor vergata, roma, italy muniversità di roma la sapienza, roma, italy nuniversità della basilicata, potenza, italy oagh - university of science and technology, faculty of computer science, electronics and telecommunications, kraków, poland plifaels, la salle, universitat ramon llull, barcelona, spain qhanoi university of science, hanoi, viet nam runiversità di padova, padova, italy suniversità di pisa, pisa, italy tscuola normale superiore, pisa, italy uuniversità degli studi di milano, milano, italy vpolitecnico di milano, milano, italy †deceased introduction the lhcb detector and data set event selection background determination systematic uncertainties results references the price of beauty and fragrance research highlights evolution the price of beauty and fragrance science , – ( ). the sweet spring season is a good time for life rebirth and renewal. in addition to enjoying the aroma of this beautiful season, sergio ramos and florian schiestl at the university of zurich, switzerland, have decoded messages on plant evolution from the interactions among blooming flowers, buzzing bees and wiggling caterpillars. pollinators and herbivores (bumble bees and caterpillars of cabbage butterfly in this study) both interact with plants but exert different selection pressures. pollinators select attractive flowers for pollen and nectar, while herbivores favour plants with fewer defences. to track the combined effects of pollinators and herbivores on the evolution of plant reproductive traits over multiple generations, ramos and schiestl used rapid-cycling brassica rapa plants to set up four treatment groups: ) hand pollination (no bees or caterpillars); ) hand pollination and caterpillars (no bees); ) bee pollination and caterpillars; and ) bee pollination (no caterpillars). interestingly, they found that group evolved larger and more fragrant flowers. however, when caterpillars were present (group ), the selection effects fade away. also, they observed that bees spent less time on plants with caterpillars (group ), and that this group of plants showed significantly reduced pistil length as well as a higher rate of self-compatibility and autonomous selfing at the eighth generation. although the mechanism has not yet been determined, this work demonstrates an important impact of herbivores on pollinator-induced reproductive evolution. now we know that rapid evolution could be driven by the previously overlooked interplays between mutualists and antagonists. next time, when encountering a bee or a caterpillar, what would you reminisce? lei lei published online: april https://doi.org/ . /s - - - credit: antje schulte / alamy stock photo nature plants | vol | may | | www.nature.com/natureplants mailto: https://doi.org/ . /s - - - http://www.nature.com/natureplants the price of beauty and fragrance [pdf] the beautiful otherness of the autistic mind | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /rstb. . corpus id: the beautiful otherness of the autistic mind @article{happ thebo, title={the beautiful otherness of the autistic mind}, author={f. happ{\'e} and u. frith}, journal={philosophical transactions of the royal society b: biological sciences}, year={ }, volume={ }, pages={ - } } f. happé, u. frith published psychology, medicine philosophical transactions of the royal society b: biological sciences of all the features of autism, none is more widely admired than the remarkable talent found so frequently with this condition. yet special talents are still less researched and less well understood than other features of autism. in popular accounts of autism, the existence of extraordinary talent in view on royal society rstb.royalsocietypublishing.org save to library create alert cite launch research feed share this paper citationsbackground citations results citations view all topics from this paper autistic disorder paper mentions news article understanding autism: how life on the spectrum fosters brilliance and limitations medical daily february blog post do not walk – run! autistic aphorisms december blog post autism and talent: why? the autism crisis may citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency autism and art. i. james medicine, art frontiers of neurology and neuroscience save alert research feed creativity, psychosis, autism, and the social brain m. fitzgerald, z. hawi psychology pdf view excerpts, cites background save alert research feed how does giftedness coexist with autistic spectrum disorders (asd)? understanding the cognitive mechanism of gifted asd kwang-han song psychology save alert research feed imagining otherwise: autism, neuroaesthetics and contemporary performance nicola shaughnessy psychology view excerpt, cites background save alert research feed critical evaluation of the concept of autistic creativity v. lyons, m. fitzgerald psychology pdf view excerpt, cites background save alert research feed autistic traits and illness trajectories l. dell’osso, p. lorenzi, b. carpita psychology, medicine clinical practice and epidemiology in mental health : cp & emh pdf save alert research feed beyond biomedicine: challenging conventional conceptualisations of autism spectrum conditions saoirse mac cárthaigh psychology save alert research feed prodigious polyglot savants: the enigmatic adjoining of language acquisition and emaciated potentials elham h. ammari psychology pdf view excerpt, cites background save alert research feed the image of mind in the language of children with autism w. hinzen, j. rosselló, o. mattos, kristen schroeder, elisabet vila psychology, medicine front. psychol. view excerpt, cites background save alert research feed finding their place in the world: what can we learn from successful autists’ accounts of their own lives? g. south, n. sunderland sociology save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency stereotypes of autism d. draaisma medicine, biology philosophical transactions of the royal society b: biological sciences pdf view excerpt, references background save alert research feed autism: explaining the enigma u. frith psychology , view excerpt, references background save alert research feed autism and abnormal development of brain connectivity m. belmonte, g. allen, a. beckel-mitchener, l. boulanger, r. carper, s. webb psychology, medicine the journal of neuroscience , pdf view excerpt, references background save alert research feed the savant syndrome: an extraordinary condition. a synopsis: past, present, future d. treffert psychology, medicine philosophical transactions of the royal society b: biological sciences pdf view excerpt, references background save alert research feed the autistic neuron: troubled translation? r. j. kelleher, m. bear biology, medicine cell view excerpt, references background save alert research feed what aspects of autism predispose to talent? f. happé, pedro vital psychology, medicine philosophical transactions of the royal society b: biological sciences pdf view excerpts, references background save alert research feed innate talents: reality or myth? m. howe, j. davidson, j. sloboda psychology, medicine the behavioral and brain sciences pdf view excerpt, references background save alert research feed assessing musical skills in autistic children who are not savants p. heaton psychology, medicine philosophical transactions of the royal society b: biological sciences pdf view excerpts, references background save alert research feed a case study of a multiply talented savant with an autism spectrum disorder: neuropsychological functioning and brain morphometry g. l. wallace, f. happé, j. giedd psychology, medicine philosophical transactions of the royal society b: biological sciences pdf view excerpts, references background save alert research feed effects of sensory input and sensory dominance on severely disturbed, autistic children and on subnormal controls. b. hermelin, n. o'connor psychology, medicine british journal of psychology save alert research feed ... ... related papers abstract topics paper mentions citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators blog posts, news articles and tweet counts and ids sourced by altmetric.com terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue the left atrium cmaj • june , ; ( ) member where to get cans of ginger ale, if a patient is thirsty for one. i am not sure where my resident is right this moment, but that doesn’t bother me. this is my last call night for the intern year and i am excited to see what the rest of the evening will bring. i can see jim wandering over from a room at the end of the unit. “hey, doc,” he says. “hey, jim.” “need you down in room . chest pain. ten out of ten.” “got it.” “start with the nitros, right?” “please.” “already gave him three,” he says. “now what do you want me to do?” time to close the notebook. “all right, jim. i’m on my way there.” hunter groninger department of internal medicine university of virginia health sciences center charlottesville, va. manufactured landscapes: the photographs of edward burtynsky curator: lori pauli, assistant curator of photographs, national gallery of canada national gallery of canada, ottawa jan. – may , art gallery of ontario, toronto jan. – apr. brooklyn museum of art, new york city sept. – dec. , the son of ukrainian immigrants,photographer edward burtynsky says his history begins in canada. it is fitting that the mid-career retrospective of his work organized by the national gallery of canada and exhibited most recently at the art gallery of ontario should open with a selection of his images of railway cuts through the rocky mountains. exactly years before, the completion of canada’s transcontinental railroad had allowed the young country to assert its nation- hood and proclaim its optimism about the future. this spirit of optimism per- meates burtynsky’s work: his pho- tographs crackle with an energy that seems to echo the spirit of new arrivals to north america seeking a better life in a fabled land of open spaces and vast potential. they also draw attention to the impact of taking this seemingly lim- itless resource for granted. burtynsky’s work is about scale: the massively altered landscapes he docu- ments are transformed into large works ranging up to cm × cm. but, as with every aspect of burtyn- sky’s carefully considered work, size is never a superfluous attribute: a huge “canvas” is necessary to convey the monumental scale of his vision and subject matter. this perfect conver- gence of form and content results in a surprising beauty. burtynsky’s work is propelled by, and communicates, the same spirit of discovery as the work of carleton watkins, who photographed the land- scape of the th-century american west. watkins was a great influence on burtynsky, whose photographs (like watkins’) are beautiful in the awe they arouse. what is unique in burtynsky’s images, however, is that he is able to render what he terms “transformed” landscapes with the same degree of sub- lime beauty as his th-century prede- cessor did in documenting those in a more natural state. burtynsky’s ability to achieve this unexpected outcome is the quality that particularly energizes his photographs and makes them so in- triguing. when considering oxford tire pile # , westley california ( ) from a lifeworks unexpected beauty edward burtynsky, . railcuts # , c.n. track, thompson river, british colum- bia. dye coupler print , cm × cm d o i: . / cm aj . n a tio n a l g a lle ry o f c a n a d a côté cœur jamc • juin ; ( ) series of photographs of the world’s largest pile of discarded rubber tires, one would expect that burtynsky would compose and frame his image to draw the viewer’s attention only to the envi- ronmental impact of such waste. al- though he does convey this message, he paradoxically chooses a muted, earth- toned palette and a raised vantage point to inject the scene with an element of grandeur, one that seems almost to cel- ebrate the enormous scale of these mountains of tires. this characteristic reinforces the sense of optimism in burtynsky’s work. part of this impression stems from his desire to photograph only the biggest examples of any given subject — tire piles in california, spent copper mines in pennsylvania, or nickel tailings out- side sudbury, ont. his images some- how manage to communicate both the optimism and the naïveté of our belief in the inexhaustibility of nature. pre- cisely capturing the inherent contradic- tions in our north american approach to life, they create an unsettling irony but are also strangely affirming. burtynsky’s photographs are not all executed in north america, but they all reveal the enormous labour required to transform the landscapes he documents. included in the ex- hibition are images of the world’s largest marble quarries in carrara, italy, and selections from a series documenting shipbreaking in chittagong, bangladesh. in this group of photographs, which physically concludes the exhibition, bur- tynsky’s work undergoes a ma- jor shift, investing his work with even greater impact. to this point, burtynsky has avoided the overt inclusion of the human presence — it is al- ways subordinate to the ma- chinery that humans have de- veloped to transform nature. in the shipbreaking series, hu- mans are much more promi- nent because of his realization that so much work in the developing world is still performed by poorly paid labourers. as he photographed the shipbreakers, dis- mantling massive freighters by hand, burtynsky was struck by their primitive working conditions. this personal in- volvement is con- veyed most com- pellingly through his photographs of the barefooted, vulnera- ble workers dwarfed by the huge hulks of ships. his inclusion of the tiny, fading marks of their foot- prints in the fore- ground sand, in im- ages such as shipbreaking # , chit- tagong, bangladesh ( ), speak vol- umes about the conditions in which these men labour. burtynsky has stated that his choice of subject matter does not stem not from a desire to editorialize on environ- mental issues or to make political state- ments about the impact of industrializa- tion. but in the shipbreaking series his sense of injustice has been aroused, in- fusing his already outstanding work with additional power. vivian tors visual artist ottawa, ont. an excellent accompanying catalogue, edited by lori pauli and published in by the national gallery of canada in association with yale university press is also available at http://national.gallery.ca. edward burtynsky, . oxford tire pile # , westley, california. dye coupler print, cm × cm edward burtynsky, . shipbreaking # , chittagong, bangladesh. dye coupler print, cm × cm k itc h e n e r- w a te rl o o a rt g a lle ry c o lle ct io n o f v a h a n a n d s u sa n k o lo lia n google sites one account. all of google. sign in to continue to google sites enter your email find my account sign in with a different account create account one google account for everything google about google privacy terms help desy - cp violation in multibody decays of beauty baryons gauthier durieux desy, notkestrasse , d- hamburg, germany abstract: beauty baryons are being observed in large number in the lhcb detector. the rich kinematics of their multibody decays are therefore becoming accessible and provide us with new opportunities to search for cp violation. we analyse the angular distributions of some three- and four-body decays of spin- / baryons using the jacob– wick helicity formalism. the asymmetries that provide access to small differences of cp- odd phases between decay amplitudes of identical cp-even phases are notably discussed. the understanding gained on processes featuring specific resonant intermediate states al- lows us to establish which asymmetries are relevant for what purpose. it is for instance shown that some cp-odd angular asymmetries measured by the lhcb collaboration in the Λb → Λ ϕ → pπ k+k− decay are expected to vanish identically. ar x iv : . v [ he p- ph ] a ug introduction despite of production rates somewhat smaller than that of mesons, beauty baryons are now being observed in significant number in the lhcb detector. they have therefore started to offer complementary means to test the standard model. the search for new sources of cp violation is an especially relevant direction in which they could provide new opportunities. incidentally, a first hint of cp violation could just have been observed in the Λb → pπ−π+π− channel [ ]. using angular momentum conservation through the jacob– wick helicity formalism, we aim at determining what angular asymmetries can be expected in specific beauty baryon decays as well as how they relate to the underlying dynamics and its discrete symmetry properties. by discussing the case of spin- / baryon decays, this paper extends ref. [ ] that focused on the case of spin- particles. most of our results also apply to the decay of any spin- / state. a violation of cp, sourced in the standard model or beyond, manifests itself through relative cp-odd phases—also called weak phases—between decay amplitudes. they can be accessed through interferences in which cp-even—or strong—phases originating from the absorptive parts of amplitudes can also appear. the most common interferences take the following form: re{a∗ a } = |a ∗ a | re { ei∆δ +i∆ϕ } = |a∗ a | ( cos ∆δ cos ∆ϕ − sin ∆δ sin ∆ϕ ) , where ∆ϕ and ∆δ respectively denote cp-odd and cp-even phase differences. the second cp-odd term can be extracted by combining cp-conjugate processes, through rate asym- metries notably. it provides sensitivity to small differences of weak phases, a sensitivity which is however conditioned on the presence of relative strong phases. some other inter- ferences take the im{a∗ a } = |a ∗ a | ( sin ∆δ cos ∆ϕ + cos ∆δ sin ∆ϕ ) form. the second cp-odd term extracted by combining cp-conjugate processes is again sensitive to small weak phase differences, but does not vanish in the absence of relative strong phases. studying this second type of interferences is therefore particularly relevant in cases where small strong phases are expected. measuring both types of interferences can also lead to a better understanding of strong phases which are difficult to compute when they result from nonperturbative dynamics. beside rate asymmetries already mentioned, differential distributions can serve to ac- cess various interference terms. exploiting the distributions of decay products instead of decay rates can also be advantageous when the production cross sections of cp-conjugate particles differ—as they generally do in pp collisions—and production rate asymmetries are not precisely known. it is useful to define motion reversal t̂ (often called naive time reversal), a transformation that reverts momentum and spin three-vectors. indeed, the motion reversal properties of differential distributions determine which type of amplitude interferences they give access to: t̂-even observables provide access to the re{a∗iaj} in- – – terferences, t̂-odd observables to the im{a∗iaj} ones. let us focus somewhat on the t̂- odd observables which thus yield sensitivity to small differences of cp-odd phases between amplitudes having small or vanishing relative cp-even phases. in a lorentz-invariant form, t̂-odd variables only appear proportional to a completely antisymmetric �µνρσ contraction of four independent four-vectors. in processes involving only spinless external states, they can thus only be constructed when at least five external particles are involved, like in four- body decays. in processes involving spinning particles, t̂-odd variables can in principle also be constructed through the antisymmetric contraction of both momentum and spin four-vectors. they constitute qualitatively different observables. unlike momenta, the spin vectors of stable particles are however practically unmeasurable in the context we are inter- ested in. so we will refrain from considering as observables the �µνρσ contractions in which they appear (that give rise to triple products like s · (pi × pj) in a specific frame). only angular distributions that derive from measured final-state momenta will be awarded that status. final-state spins will be altogether disregarded and summed over. the polarisation of the decaying particle can however be considered as resulting from the production process since it is determined by production amplitudes. in the decay of spinning particles, the angular distributions of decay products can then be viewed a providing access to combin- ations of production and decay amplitudes. this is to be contrasted with the decays of spinless particles where they provide direct access to decay amplitudes. from this more practical point of view, here is how spinning particles offer new oppor- tunities to search for small differences of cp-odd phases between decay amplitudes that have identical—potentially vanishing—cp-even phases. as a matter of fact, t̂-even angu- lar distributions still provide access to small cp-odd phase differences only in the presence of relative cp-even phases. the latter can however appear in the production amplitudes, as angular distributions now give access to an entwined combination of production and decay amplitudes. such strong phases in production amplitudes would manifest themselves as a nonvanishing t̂-odd polarisation component, which we will denote pz. as a result, certain imaginary parts of decay amplitude interferences become accessible through t̂-even angular distributions, in terms proportional to this t̂-odd polarisation component of the decaying particle. in particular, there are not enough independent external-particle four-momenta in three-body decays to form an antisymmetric �µνρσ contraction. one must necessarily rely on at least one spin four-vector to form a t̂-odd variable. as will be illustrated below with final-state spins summed over, the imaginary parts of decay amplitude interferences then only appear in terms proportional to the decaying particle polarisation. a positive signal of cp violation in one of the corresponding asymmetries could thus be sourced either in decay amplitudes or in production ones, leading, in the latter case, to a mismatch between the polarisation of the initial particle and minus the polarisation of its antiparticle. such an effect is not expected to be sizeable when the strong interaction which conserves cp dominates the production process. without assuming it is altogether absent, one would have to rely on a comparison between the expected and measured patterns of asymmetries to discriminate between these two possibilities. the patterns expected for decays through specific resonant intermediate states are presented below. on the other hand, all the t̂-odd angular distributions can no longer serve to isolate – – b a / , / / / / / b a / , / / / a / , / / b / a / , / / b / figure . the eight three- and four-body decays considered in this paper. the superscripts to particles’ labels specify their spins. small differences of cp-odd phases between decay amplitudes of identical cp-even phases. the t̂-odd angular distributions that appear proportional to pz no longer give access to imaginary parts of decay amplitude interferences. sensitivity to hypothetical cp-odd phase differences through these terms then actually relies on the presence of nonvanishing cp-even phase differences between the corresponding decay amplitudes. a systematic and blind construction of t̂-odd–cp-odd asymmetries, as performed in ref. [ ] for the decay of spinless particles, is still possible. we stress this procedure can still be utilized experimentally to cover the unexpected or in situations where complicated patterns of interferences are not described precisely enough. one would however need to rely on specific results such as the ones presented here for selected resonance structures to establish whether a given t̂-odd angular asymmetry yields sensitivity to cp-odd phase differences between production or decay amplitudes. aside from cp violation, one can in principle measure all prescribed independent con- tributions to the angular distributions and thereby gain further understanding about the process under scrutiny. our tables establish the necessary link between kinematic distri- butions and the dynamics encoded in amplitudes. the precision achieved will obviously depend on the collected statistics, but note the determination of each asymmetry or mo- ment exploits the statistical power of the full data sample. this is to be contrasted with a fit in which additional free parameters worsen the precision to which all of them can be determined (see e.g. ref. [ ]). angular distributions the following four- and three-body decays (depicted in fig. ) will be considered: / −→ a / , / b −→ / / / , −→ / , / −→ a / , / b −→ / b , −→ a / , / b −→ / b , where the superscripts of particle labels specify their spins. examples of such processes include the Λb → Λ j/ψ → pπ µ+µ−, Λb → Λ ϕ → pπ k+k−, Λb → n∗ks → pπks – – z x yθ φ θa θb xa zayaxb zb yb b a figure . reference frames defined according to the jackson convention [ ] where axes in the two daughter restframes are (anti)aligned. the azimuthal angles φa,b that are not apparent are defined in the usual way: measured from the xa,b axes such that the ya,b axes have φa,b = +π/ . note the a,b particles’ momenta are pictured in the particle restframe, while the , and , ones in the a and b restframes, respectively. decays which were studied by the lhcb collaboration in the recent refs. [ – ], or the Λb → Λ(x)γ → pk/π γ processes discussed in refs. [ – ]. the helicity formalism of jakob and wick [ ] will be employed, following the so-called jackson convention [ ] for the definition of the various reference frames (see fig. ). the spins of final-state particles will be summed over. on the other hand, a nonvanishing polar- isation of the initial spin- / baryon will be considered. although experimental datasets never isolate perfectly one single resonant intermediate state, the interferences between them lie beyond the scope of this work. neither will topologies like be considered. a first (x, y, z) system of axes is defined in the restframe of the initial—mother— particle . when the production of the latter preserves parity, its polarisation vector is orthogonal to the production plane (see sec. v of ref. [ ]). to take advantage of this fea- ture, the z axis is taken parallel to the normal of the production plane. so is a transversity frame obtained. particles a and b are respectively produced at polar angles θ and π − θ from that z axis. with the spin vector of particle pointing exactly in the z direction, no dependence on the azimuthal angle φ of particle a is generated. the direction of the x axis is therefore chosen arbitrarily in the plane perpendicular to the z axis. two other systems of axes are defined in the restframes of the a and b daughters, as so-called helicity frames. the second one will only be relevant for four-body decays. the (xa, ya, za) system is obtained by a r(φ,θ, )t euler rotation of the initial (x, y, z) one, alternatively, a helicity frame could have been obtained with z aligned to particle momentum in the laboratory frame (see refs. [ – ] for some results obtained in such a frame). a r(φ,θ,χ) transformation is the succession of three elementary rotations around the z, y, and z axes: rz (φ)ry (θ)rz (χ). in the so-called jacob–wick convention, the (xa, ya, za) frame is obtained by a r(φ,θ, −φ)t rotation of the (x, y, z) one. – – followed by a suitable boost in the za direction (parallel to particle a’s momentum in the mother restframe). a r(φ + π,π −θ, )t rotation followed by a boost in the zb direction is required to obtain the (xb, yb, zb) system. its axes are parallel or antiparallel to the (xa, ya, za) ones. the following assumptions will be made in the main text and released in appendix a: • the production of particle preserves parity, so that its polarisation (if any) is aligned with the z axis. one therefore has px = = py in the density matrix for particle / : ρ(m ,m′ ) = ( + / − / + / + pz px − ipy − / px + ipy −pz ) where m(′) is the component of particle ’s spin along the z axis. • when appearing as a final-state particle, in the three-body decays we consider, the b vector is taken massless so that it has no λb = zero helicity state (and the a± amplitudes defined below are absent). • the b → / / decay preserves parity, so that its helicity amplitudes satisfy |mb(−λ ,−λ )| = |mb(+λ , +λ )| . • the / and / particles arising from the b vector decay are massless and therefore have opposite helicities: λ = −λ . in each four-body process considered here, for the b decay, there is therefore one single independent combination of squared helicity amplitudes: either |mb( / ,− / )| + |mb(− / , / )| , or |mb( , )| . they will be absorbed into the definition of the m helicity amplitudes for the parent → ab decay. we will also absorb in the m ’s the |ma(+ / , )| + |ma(− / , )| combination of a / , / → / amplitudes and define the αa ≡ |ma(+ / , )| −|ma(− / , )| |ma(+ / , )| + |ma(− / , )| asymmetry parameter which violates parity p. it is therefore expected to vanish if the corresponding decay proceeds through the strong interaction, like in the Λ( ) → pk example of a / → / decay. the helicity combinations allowed for the a,b system are (λa,λb) = (± / , ), and (± / ,± ) for a spin- / particle a / , as well as (± / ,± ) for a spin- / particle a / . we will denote the corresponding amplitudes as a± ≡ m (± / , ), b± ≡ m (± / ,± ), c± ≡ m (± / ,± ). as opposed to the rates of the four-body decays featuring b as an intermediate particle, the three-body ones in which it appears in the final state will only contain interferences between – – amplitudes of identical λb. note also that a massless b vector produced onshell can only have λb = ± . the a± amplitudes therefore vanish in that case. as already mentioned, this will be assumed in the main text for the three-body / → a / , / b → / b decays. finally, beyond the narrow width approximation for particles a and b, the a±,b±,c± as well as αa amplitudes have a non-trivial dependence on the ( ) and ( ) invariant masses which we will respectively denote ma and mb. the various contributions to the dΓ/dΩ angular distributions of the final-state particles for the processes depicted in fig. are given in table – . the overall normalisation is chosen such that the∫ dΩ ≡ + ∫ − d cos θ + ∫ − d cos θa + ∫ − d cos θb +π∫ −π dφ π +π∫ −π dφa π +π∫ −π dφb π angular integration simply yields the sum of the allowed amplitudes squared. in case all the six of them are present, one would then get∫ dΩ dΓ dΩ = |a+| + |a−| + |b+| + |b−| + |c+| + |c−| . here, again, the dependence on the ma,b invariant masses is kept implicit. some of the angular distributions given here have already been presented elsewhere, sometimes partially only. table agrees with the table of ref. [ ]. table agrees with eq. ( ) of ref. [ ]. the terms in table that are not proportional to αa only match eq. ( ) of ref. [ ], provided w and w defined there are respectively multiplied by factors of ±pz. the relative sign between these b+c+ and b−c− interferences can be understood given the dj−µ,−λ(θ) = (− ) λ−µd j µ,λ(θ) symmetry relations between wigner matrices (see eq. (a ) of ref. [ ]). note also a relative complex conjugation of the amplitudes defined here and there, as well as the use of the jacob–wick convention there which leads to expressions identical to the ones we obtain with the jackson convention for the terms compared when φΛ is set to there. both table and the a± dependence of table agree with eq. ( ) and ( ) of ref. [ ], obtained with pz = + . discrete symmetry properties to establish the parity p and motion reversal t̂ transformation properties of the various contributions to the differential distributions displayed in table – , let us define our kinematic variables and axes in terms of physical momenta. in the restframe of particle , let us assume that the production plane is defined by the momenta pa and pb of two of the particles involved. one can then construct the (x, y, z) frame as x = pa |pa| , z = pa × pb |pa × pb| , y = z × x. the z axis is thus a p-even–t̂-even pseudovector, while x and y are both p-odd–t̂-odd vectors. the (xa, ya, za) system is then obtained as za = p + p |p + p | , ya = z × za |z × za| , xa = ya × za |ya × za| , – – + / |a+| + |a−| sin θb + / |b+| + |b−| + cos θb + / |a+| −|a−| αa cos θa sin θb + / |b+| −|b−| αa cos θa + cos θb − / √ re { a∗+b− } − re { a∗−b+ } αa sin θa sin θb cos(φa + φb) + / |a+| −|a−| pz cos θ sin θb − / |b+| −|b−| pz cos θ + cos θb − / √ re { a∗+b+ } − re { a∗−b− } pz sin θ sin θb cos φb + / |a+| + |a−| αa pz cos θ cos θa sin θb − / |b+| + |b−| αa pz cos θ cos θa + cos θb − / √ re { a∗+b− } + re { a∗−b+ } αa pz cos θ sin θa sin θb cos(φa + φb) − / √ re { a∗+b+ } + re { a∗−b− } αa pz sin θ cos θa sin θb cos φb − re { a∗+a− } αa pz sin θ sin θa sin θb cos φa − / re { b∗+b− } αa pz sin θ sin θa sin θb cos(φa + φb) + / √ im { a∗+b+ } + im { a∗−b− } pz sin θ sin θb sin φb − / √ im { a∗+b− } − im { a∗−b+ } αa pz cos θ sin θa sin θb sin(φa + φb) + / √ im { a∗+b+ } − im { a∗−b− } αa pz sin θ cos θa sin θb sin φb − im { a∗+a− } αa pz sin θ sin θa sin θb sin φa − / im { b∗+b− } αa pz sin θ sin θa sin θb sin(φa + φb) − / √ im { a∗+b− } + im { a∗−b+ } αa sin θa sin θb sin(φa + φb) table . various contributions to the angular distribution of the / → a / b → / / / process, with conventions and assumptions specified in the text. each line corresponds to a term of different angular dependence (most of them being independent). the separation in columns is only meant to ease the comparison between the various factors appearing in each term. the four blocks distinguish terms whose combinations of angular and polarisation dependence have different parity and motion reversal transformation properties. they are respectively p-even–t̂-even, p-odd–t̂- even, p-even–t̂-odd, and p-odd–t̂-odd. where p and p are the momenta of particles and in particle ’s restframe. it follows that both za and ya are p-odd–t̂-odd vectors while xa is a p-even–t̂-even pseudovector. similar conclusions hold for (xb, yb, zb) = (−xa, ya,−za). the polar θ and azimuthal φ angles can be obtained from the equalities: cos θ = z ·za, sin θ = + √ − cos θ, cos φ = (z ×za) ·y, sin φ = −(z ×za) ·x, which establish that cos θ is a p-odd–t̂-odd kinematic variable, while sin θ, cos φ, and sin φ are p-even–t̂-even. moreover, defining the p-even–t̂-even pseudovectors na = p × p |p × p | , nb = p × p |p × p | , – – + / |b+| + |b−| + |c+| + |c−| + cos θb − √ / / re { a∗+c+ } + re { a∗−c− } sin θa sin θb cos(φa + φb) + / |a+| + |a−| ( + cos θa) sin θb − √ / re { b∗+c− } + re { b∗−c+ } sin θa sin θb cos( φa + φb) + / |b+| + |b−| −|c+| −|c−| cos θa + cos θb − / |b+| − |b−| − |c+| + |c−| αa cos θa + cos θb − / |a+| −|a−| αa ( − cos θa) cos θa sin θb + √ / / re { a∗+c+ } − re { a∗−c− } αa ( − cos θa) sin θa sin θb cos(φa + φb) + / √ re { a∗+b− } − re { a∗−b+ } αa ( − cos θa) sin θa sin θb cos(φa + φb) + √ / re { b∗+c− } − re { b∗−c+ } αa sin θa cos θa sin θb cos( φa + φb) + / |b+| − |b−| −|c+| + |c−| αa cos θa + cos θb − / |b+| −|b−| − |c+| + |c−| pz cos θ + cos θb − √ / / re { a∗+c+ } − re { a∗−c− } pz cos θ sin θa sin θb cos(φa + φb) + / |a+| −|a−| pz cos θ ( + cos θa) sin θb + √ / re { b∗+c− } − re { b∗−c+ } pz cos θ sin θa sin θb cos( φa + φb) − / |b+| −|b−| + |c+| −|c−| pz cos θ cos θa + cos θb + √ / re { b∗+c+ } − re { b∗−c− } pz sin θ sin θa + cos θb cos φa − / √ re { a∗+b+ } − re { a∗−b− } pz sin θ ( + cos θa) sin θb cos φb − √ / / re { a∗+c− } − re { a∗−c+ } pz sin θ sin θa sin θb cos( φa + φb) + / |b+| + |b−| + |c+| + |c−| αa pz cos θ cos θa + cos θb − / |a+| + |a−| αa pz cos θ ( − cos θa) cos θa sin θb + √ / / re { a∗+c+ } + re { a∗−c− } αa pz cos θ ( − cos θa) sin θa sin θb cos(φa + φb) + / √ re { a∗+b− } + re { a∗−b+ } αa pz cos θ ( − cos θa) sin θa sin θb cos(φa + φb) − √ / re { b∗+c− } + re { b∗−c+ } αa pz cos θ sin θa cos θa sin θb cos( φa + φb) − / |b+| + |b−| + |c+| + |c−| αa pz cos θ cos θa + cos θb + / √ re { a∗+b+ } + re { a∗−b− } αa pz sin θ ( − cos θa) cos θa sin θb cos φb − √ / re { b∗+c+ } + re { b∗−c− } αa pz sin θ ( − cos θa) sin θa + cos θb cos φa + / re { a∗+a− } αa pz sin θ ( − cos θa) sin θa sin θb cos φa + / re { b∗+b− } αa pz sin θ ( − cos θa) sin θa sin θb cos(φa + φb) + / re { c∗+c− } αa pz sin θ sin θa sin θb cos( φa + φb) + √ / / re { a∗+c− } + re { a∗−c+ } αa pz sin θ sin θa cos θa sin θb cos( φa + φb) + √ / / im { a∗+c+ } + im { a∗−c− } pz cos θ sin θa sin θb sin(φa + φb) + √ / im { b∗+c− } + im { b∗−c+ } pz cos θ sin θa sin θb sin( φa + φb) − √ / im { b∗+c+ } + im { b∗−c− } pz sin θ sin θa + cos θb sin φa + / √ im { a∗+b+ } + im { a∗−b− } pz sin θ ( + cos θa) sin θb sin φb − √ / / im { a∗+c− } + im { a∗−c+ } pz sin θ sin θa sin θb sin( φa + φb) − √ / / im { a∗+c+ } − im { a∗−c− } αa pz cos θ ( − cos θa) sin θa sin θb sin(φa + φb) + / √ im { a∗+b− } − im { a∗−b+ } αa pz cos θ ( − cos θa) sin θa sin θb sin(φa + φb) − √ / im { b∗+c− } − im { b∗−c+ } αa pz cos θ sin θa cos θa sin θb sin( φa + φb) − / √ im { a∗+b+ } − im { a∗−b− } αa pz sin θ ( − cos θa) cos θa sin θb sin φb + √ / im { b∗+c+ } − im { b∗−c− } αa pz sin θ ( − cos θa) sin θa + cos θb sin φa + / im { a∗+a− } αa pz sin θ ( − cos θa) sin θa sin θb sin φa + / im { b∗+b− } αa pz sin θ ( − cos θa) sin θa sin θb sin(φa + φb) + / im { c∗+c− } αa pz sin θ sin θa sin θb sin( φa + φb) + √ / / im { a∗+c− } − im { a∗−c+ } αa pz sin θ sin θa cos θa sin θb sin( φa + φb) + √ / / im { a∗+c+ } − im { a∗−c− } sin θa sin θb sin(φa + φb) − √ / im { b∗+c− } − im { b∗−c+ } sin θa sin θb sin( φa + φb) − √ / / im { a∗+c+ } + im { a∗−c− } αa ( − cos θa) sin θa sin θb sin(φa + φb) + / √ im { a∗+b− } + im { a∗−b+ } αa ( − cos θa) sin θa sin θb sin(φa + φb) + √ / im { b∗+c− } + im { b∗−c+ } αa sin θa cos θa sin θb sin( φa + φb) table . same as table , for the / → a / b → / / / process where particle a has spin / instead of / . – – + |a+| + |a−| cos θb + / |b+| + |b−| sin θb + |a+| −|a−| αa cos θa cos θb + / |b+| −|b−| αa cos θa sin θb + / √ re { a∗+b− } − re { a∗−b+ } αa sin θa sin θb cos(φa + φb) + |a+| −|a−| pz cos θ cos θb − / |b+| −|b−| pz cos θ sin θb + / √ re { a∗+b+ } − re { a∗−b− } pz sin θ sin θb cos φb + |a+| + |a−| αa pz cos θ cos θa cos θb − / |b+| + |b−| αa pz cos θ cos θa sin θb + / √ re { a∗+b− } + re { a∗−b+ } αa pz cos θ sin θa sin θb cos(φa + φb) + / √ re { a∗+b+ } + re { a∗−b− } αa pz sin θ cos θa sin θb cos φb − re { a∗+a− } αa pz sin θ sin θa cos θb cos φa + re { b∗+b− } αa pz sin θ sin θa sin θb cos(φa + φb) − / √ im { a∗+b+ } + im { a∗−b− } pz sin θ sin θb sin φb + / √ im { a∗+b− } − im { a∗−b+ } αa pz cos θ sin θa sin θb sin(φa + φb) − / √ im { a∗+b+ } − im { a∗−b− } αa pz sin θ cos θa sin θb sin φb − im { a∗+a− } αa pz sin θ sin θa cos θb sin φa + im { b∗+b− } αa pz sin θ sin θa sin θb sin(φa + φb) + / √ im { a∗+b− } + im { a∗−b+ } αa sin θa sin θb sin(φa + φb) table . various contributions to the angular distribution of the / → a / b → / process, with conventions and assumptions specified in the text. each line corresponds to a term of different angular dependence (most of them being independent). the separation in columns is only meant to ease the comparison between the various factors appearing in each term. the four blocks distinguish terms whose combinations of angular and polarisation dependence have different parity and motion reversal transformation properties. they are respectively p-even–t̂-even, p-odd–t̂- even, p-even–t̂-odd, and p-odd–t̂-odd. where p and p are the momenta of particles and in particle ’s restframe, one can further write ( = na · za, ) cos φa = −na · ya, sin φa = na · xa, and similarly for a ↔ b. this shows that cos φa and cos φb are p-odd–t̂-odd variables, while sin φa and sin φb are p-even–t̂-even. with p̃ and p̃ , the momenta of particle and , respectively measured in the particle a and b restframes, one can finally define cos θa = za · p̃ |p̃ | , sin θa = + √ − cos θa, and similarly for a ↔ b and ↔ , demonstrating that both cos θa,b and sin θa,b are p- even–t̂-even variables. finally, the p-odd–t̂-odd character of the vector z implies that – – + / |b+| + |b−| + |c+| + |c−| sin θb + √ / / re { a∗+c+ } + re { a∗−c− } sin θa sin θb cos(φa + φb) + / |a+| + |a−| ( + cos θa) cos θb + √ / re { b∗+c− } + re { b∗−c+ } sin θa sin θb cos( φa + φb) + / |b+| + |b−| −|c+| −|c−| cos θa sin θb − / |b+| − |b−| − |c+| + |c−| αa cos θa sin θb − / |a+| −|a−| αa ( − cos θa) cos θa cos θb − √ / / re { a∗+c+ } − re { a∗−c− } αa ( − cos θa) sin θa sin θb cos(φa + φb) − / √ re { a∗+b− } − re { a∗−b+ } αa ( − cos θa) sin θa sin θb cos(φa + φb) − √ / re { b∗+c− } − re { b∗−c+ } αa sin θa cos θa sin θb cos( φa + φb) + / |b+| − |b−| −|c+| + |c−| αa cos θa sin θb − / |b+| −|b−| − |c+| + |c−| pz cos θ sin θb + √ / / re { a∗+c+ } − re { a∗−c− } pz cos θ sin θa sin θb cos(φa + φb) + / |a+| −|a−| pz cos θ ( + cos θa) cos θb − √ / re { b∗+c− } − re { b∗−c+ } pz cos θ sin θa sin θb cos( φa + φb) − / |b+| −|b−| + |c+| −|c−| pz cos θ cos θa sin θb + √ / re { b∗+c+ } − re { b∗−c− } pz sin θ sin θa sin θb cos φa + / √ re { a∗+b+ } − re { a∗−b− } pz sin θ ( + cos θa) sin θb cos φb + √ / / re { a∗+c− } − re { a∗−c+ } pz sin θ sin θa sin θb cos( φa + φb) + / |b+| + |b−| + |c+| + |c−| αa pz cos θ cos θa sin θb − / |a+| + |a−| αa pz cos θ ( − cos θa) cos θa cos θb − √ / / re { a∗+c+ } + re { a∗−c− } αa pz cos θ ( − cos θa) sin θa sin θb cos(φa + φb) − / √ re { a∗+b− } + re { a∗−b+ } αa pz cos θ ( − cos θa) sin θa sin θb cos(φa + φb) + √ / re { b∗+c− } + re { b∗−c+ } αa pz cos θ sin θa cos θa sin θb cos( φa + φb) − / |b+| + |b−| + |c+| + |c−| αa pz cos θ cos θa sin θb − / √ re { a∗+b+ } + re { a∗−b− } αa pz sin θ ( − cos θa) cos θa sin θb cos φb − √ / re { b∗+c+ } + re { b∗−c− } αa pz sin θ ( − cos θa) sin θa sin θb cos φa + re { a∗+a− } αa pz sin θ ( − cos θa) sin θa cos θb cos φa − / re { b∗+b− } αa pz sin θ ( − cos θa) sin θa sin θb cos(φa + φb) − / re { c∗+c− } αa pz sin θ sin θa sin θb cos( φa + φb) − √ / / re { a∗+c− } + re { a∗−c+ } αa pz sin θ sin θa cos θa sin θb cos( φa + φb) − √ / / im { a∗+c+ } + im { a∗−c− } pz cos θ sin θa sin θb sin(φa + φb) − √ / im { b∗+c− } + im { b∗−c+ } pz cos θ sin θa sin θb sin( φa + φb) − √ / im { b∗+c+ } + im { b∗−c− } pz sin θ sin θa sin θb sin φa − / √ im { a∗+b+ } + im { a∗−b− } pz sin θ ( + cos θa) sin θb sin φb + √ / / im { a∗+c− } + im { a∗−c+ } pz sin θ sin θa sin θb sin( φa + φb) + √ / / im { a∗+c+ } − im { a∗−c− } αa pz cos θ ( − cos θa) sin θa sin θb sin(φa + φb) − / √ im { a∗+b− } − im { a∗−b+ } αa pz cos θ ( − cos θa) sin θa sin θb sin(φa + φb) + √ / im { b∗+c− } − im { b∗−c+ } αa pz cos θ sin θa cos θa sin θb sin( φa + φb) + / √ im { a∗+b+ } − im { a∗−b− } αa pz sin θ ( − cos θa) cos θa sin θb sin φb + √ / im { b∗+c+ } − im { b∗−c− } αa pz sin θ ( − cos θa) sin θa sin θb sin φa + im { a∗+a− } αa pz sin θ ( − cos θa) sin θa cos θb sin φa − / im { b∗+b− } αa pz sin θ ( − cos θa) sin θa sin θb sin(φa + φb) − / im { c∗+c− } αa pz sin θ sin θa sin θb sin( φa + φb) − √ / / im { a∗+c− } − im { a∗−c+ } αa pz sin θ sin θa cos θa sin θb sin( φa + φb) − √ / / im { a∗+c+ } − im { a∗−c− } sin θa sin θb sin(φa + φb) + √ / im { b∗+c− } − im { b∗−c+ } sin θa sin θb sin( φa + φb) + √ / / im { a∗+c+ } + im { a∗−c− } αa ( − cos θa) sin θa sin θb sin(φa + φb) − / √ im { a∗+b− } + im { a∗−b+ } αa ( − cos θa) sin θa sin θb sin(φa + φb) − √ / im { b∗+c− } + im { b∗−c+ } αa sin θa cos θa sin θb sin( φa + φb) table . same as table , for the / → a / b → / process, where particle a has spin / instead of / . – – + |b+| + |b−| + |b+| −|b−| αa cos θa − |b+| −|b−| pz cos θ − |b+| + |b−| αa pz cos θ cos θa table . contributions to the angular distribution of the three-body / → a / b → / b decay, under the conventions and assumptions specified in the text. the four blocks distinguish terms whose combinations of angular and polarisation dependence are respectively p-even–t̂-even and p-odd–t̂-even. a third block, which receives no contributions here, includes p-even–t̂-odd decay terms in the subsequent tables of this series. + / |b+| + |b−| ( + cos θa) + / |c+| + |c−| sin θa − / |b+| −|b−| αa ( − cos θa) cos θa + / |c+| −|c−| αa sin θa sin θa + √ re { b∗+c+ } − re { b∗−c− } pz sin θ sin θa cos φa − / |b+| −|b−| pz cos θ ( + cos θa) + / |c+| −|c−| pz cos θ sin θa − √ re { b∗+c+ } + re { b∗−c− } αa pz sin θ ( − cos θa) sin θa cos φa + / |b+| + |b−| αa pz cos θ ( − cos θa) cos θa + / |c+| + |c−| αa pz cos θ sin θa sin θa − √ im { b∗+c+ } + im { b∗−c− } pz sin θ sin θa sin φa + √ im { b∗+c+ } − im { b∗−c− } αa pz sin θ ( − cos θa) sin θa sin φa table . same as table , for the / → a / b → / b process, where particle a has spin / instead of / . + |a+| + |a−| + |a+| −|a−| αa cos θa + |a+| −|a−| pz cos θ − re { a∗+a− } αa pz sin θ sin θa cos φa + |a+| + |a−| αa pz cos θ cos θa − im { a∗+a− } αa pz sin θ sin θa sin φa table . same as table , for the / → a / b → / b process, where particle b has spin instead of . – – + / |a+| + |a−| ( + cos θa) − / |a+| −|a−| αa ( − cos θa) cos θa + / |a+| −|a−| pz cos θ ( + cos θa) + re { a∗+a− } αa pz sin θ ( − cos θa) sin θa cos φa − / |a+| + |a−| αa pz cos θ ( − cos θa) cos θa + im { a∗+a− } αa pz sin θ ( − cos θa) sin θa sin φa table . same as table , for the / → a / b → / b process, where particle a has spin / instead of / . among the polarisations components px = 〈s · x〉, py = 〈s · y〉, pz = 〈s · z〉, px and py are p-odd–t̂-even, while pz is p-even–t̂-odd. their values are fixed by particle ’s production amplitudes and, in general, depend on the production kinematics which is disregarded here. to summarize, for our definition of frames, we have thus identified three p-odd–t̂-odd kinematic variables: cos θ, cos φa, and cos φb, while sin θ, cos φ, sin φ, cos θa,b, sin θa,b, as well as ma,b which are necessary to fully specify the final-state kinematics, are all p-even–t̂-even. the contributions to the angular distri- butions we displayed in table – have been grouped according to their p and t̂ transform- ation properties. in table – relating to four-body decays, the angular distributions of the contributions in the first and third blocks are p-even–t̂-even while that of the second and fourth ones are p-odd–t̂-odd. the second and third blocks moreover include contributions proportional to the p-even–t̂-odd polarisation pz. as a result, the four blocks distinguish contributions whose combinations of angular and polarisation dependence are respectively p-even–t̂-even, p-odd–t̂-even, p-even–t̂-odd, and p-odd–t̂-odd. in three-body decays, there are not enough independent four-momenta to form t̂-odd �µνρσ p µ p ν p ρ p σ contrac- tions. one must necessarily involve a spin four-vector. in table – , all terms proportional to imaginary parts of decay amplitude interferences therefore come proportional to pz. they thus appear in p-even–t̂-odd blocks, and there are no fourth p-odd–t̂-odd ones. the / → a / b → / b decay relating to table does moreover not contain any term proportional to the imaginary part of decay amplitude interferences when b is mass- less (an assumption relaxed in appendix a). asymmetries as mentioned in the introduction, due to the presence of a t̂-odd polarisation component pz, both t̂-odd and t̂-even angular asymmetries can potentially serve to access imaginary parts of decay amplitude interferences. – – . t̂-odd angular asymmetries in the spirit of ref. [ ], t̂-odd–cp-odd angular asymmetries could be constructed system- atically as ajklmno ≡ ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign { fj(cos θ) fk(cos θa) fl(cos θb) sin ( mφa + nφb + o π )} for f (x) = , f (x) = x, f (x) = x − , etc. which could be chosen as legendre poly- nomials and various j,k, l,m,n,o combinations of integers satisfying j + m + n + o ∈ z with o ∈{ , }. contributions not explicitly listed in the various tables of this paper could appear in the interferences of amplitudes featuring a and b intermediate states of various spins or different topologies. it was also noted in ref. [ ] that distinguishing regions in the ma,b invariant mass integration could be useful when resonances are identified, and that pairings of final-state particles different from the a = ( ), b = ( ) ones could increase the sensitivity to phase differences between amplitudes of different resonance structures. un- derstanding the origin of the various angular distribution components is however required to determine whether a symmetry violation observed arises from the decay or production, given the lack of decoupling between the two parts of the process. this understanding we gained in the previous section allows us to be more specific. in both four-body processes featuring a spin- / intermediate resonance a, under the assump- tions stated, there is actually one single t̂-odd angular distribution that provides access to cp-odd phase differences between decay amplitudes, without requiring cp-even phase between neither decay nor production amplitudes. the corresponding term is displayed in the fourth blocks of tables and . by relying on the Γ ∫ dΩ dΓ dΩ sign{cos θb sin(φa + φb)} asymmetry, or on the analogue moment, one gets access to the (im { a∗+b− } +im { a∗−b+ } )αa combination of decay amplitudes. then combining the cp-conjugate → and ̄ → ̄ ̄ ̄ ̄ processes to form a yields sensitivity to small differences in the cp-odd phases between the a+b− or a−b+ amplitudes. it is maximal when they have identical cp-even phases. in both four-body processes featuring a spin / intermediate resonance a, one could moreover employ on the a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{cos θa cos θb sin(φa + φb)} a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{sin( φa + φb)} a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{( cos θa − ) cos θb sin(φa + φb)} a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{cos θa sin( φa + φb)} – – asymmetries (see tables and ). note the latter two as well as a come propor- tional to the asymmetry parameter αa which vanishes if the a / → / decay preserves parity, as Λ( ) → pk does, being mediated by the strong interaction. a sign{( − cos θa) cos θb sin(φa+φb)} asymmetry which is not independent of the sign{cos θb sin(φa+ φb)} and sign{( cos θa − ) cos θb sin(φa + φb)} ones has not been listed. let us also comment on the classical a asymmetry, based on sign{sin(φa + φb)}, which changes sign where the antisymmetry contraction of the four independent external particle momenta �µνρσ p µ p ν p ρ p σ does. its use for studying cp violation in the decay of Λb and Ξb baryons was advocated in ref. [ ]. we however stress that contrarily to the four-body decay of spinless particles where it can play a significant role, it vanishes in the four four-body decays considered here, under the assumptions stated. examining table – where these assumptions are relaxed, one realises such an asymmetry only appears proportional to the αb asymmetry parameters in the / → a / , / b → / / / decays. even in such processes, its presence is therefore seen to require parity violation in the b → / / daughter decay (which would for instance be absent in electromagnetic j/ψ → `+`− decays). following refs. [ – ], the lhcb collaboration measured the four Γ ∫ dΩ dΓ dΩ sign{ cos Φa,b , sin Φa,b } asymmetries in the Λb → Λ ϕ → pπ k+k− decay [ ]. the original definitions of those so-called special angles are easily seen to be equivalent to: cos Φa = na · x√ − (na · z) , sin Φa = na · y√ − (na · z) , and similarly for a ↔ b. using (x, y, z)t = r(φ,θ, )(xa, ya, za)t , xy z   =  cos θ cos φ −sin φ sin θ cos φcos θ sin φ cos φ sin θ sin φ −sin θ cos θ    xaya za   , as well as (x, y, z)t = r(π + φ,π −θ, )(xb, yb, zb)t , one derives cos Φa = cos θ cos φ sin φa + sin φ cos φa√ − sin φa sin θ , sin Φa = cos θ sin φ sin φa − cos φ cos φa√ − sin φa sin θ , cos Φb = cos θ cos φ sin φb − sin φ cos φb√ − sin φb sin θ , sin Φb = cos θ sin φ sin φa + cos φ cos φb√ − sin φb sin θ . such angular dependences do not appear in table . we therefore stress that these four asymmetries vanish identically in the / → a / b → / / / process, when Λb is produced by the strong interaction which preserves parity. referring to table , we note the same conclusion would also hold in / → a / b → / / / processes like Λb → Λ j/ψ → pπ µ+µ−. relaxing the assumptions of our main text, tables and in appendix a inform us that, in both processes, asymmetries or moments based on cos Φa – – and sin Φa are respectively sensitive to the im { a∗+a− } αapx and im { a∗+a− } αapy combin- ations of production and decay amplitudes. in the / → a / b → / / / decay, cos Φb and sin Φb asymmetries respectively provide access to ( im { a∗+b+ } − im { a∗−b− }) αbpx and ( im { a∗+b+ } − im { a∗−b− }) αbpy. they however vanish identically in the / → a / b → / case. . t̂-even angular asymmetries with a nonvanishing t̂-odd polarisation component pz produced by absorptive parts in the production amplitudes, one could also search for cp-odd phase differences between decay amplitudes that have identical or vanishing strong phases through t̂-even angular asymmetries. in the four-body processes featuring an intermediate resonance a of spin / , this is for instance possible with the a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{cos θb sin(φb)}, a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{cos θ cos θb sin(φa + φb)}, a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{cos θa cos θb sin(φb)}, a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{sin(φa)}, a = ∫ dΩ ( Γ dΓ dΩ − Γ̄ dΓ̄ dΩ ) sign{sin(φa + φb)}, asymmetries (see tables and ). only the first of these is not proportional to the asym- metry parameter αa, on top of pz. many more of such asymmetries can be constructed in the case a is of spin / and we refer the reader to the third blocks of tables and . the third blocks of tables to are relevant for three-body processes (table has no such block). it is worth stressing here that the polarisation of the Λb’s observed to decay to a j/ψΛ final state in the lhcb detector has been constrained to be smaller than % at the . σ level [ ]. in principle, the above asymmetries could also be nonvanishing in the presence of cp violation in the production process, combined with strong phase differences between decay amplitudes. this is not expected to happen when the production process is dominated by the strong interaction but could also be checked experimentally by measuring various asymmetries. since cp violation in production would cause |pz| to take slightly different values in the two conjugated processes, all the above asymmetries could potentially be non- vanishing. moreover, the t̂-odd angular asymmetries giving access to terms proportional to pz (in the second blocks of our tables) would then be nonvanishing even in the absence of cp-even phase differences between decay amplitudes. in this sense, our tables would allow to interpret the patterns observed in the measurement of various asymmetries. – – summary we have studied the angular distributions of some three- and four-body decays of spin- / states, focusing on the discrete symmetry transformation properties of the different contri- butions. some cp-odd asymmetries discussed in the literature have been shown to vanish identically in the decay chains considered. special attention has been devoted to the two types of angular asymmetries that could serve to access small differences of cp-odd phases between decay amplitudes of identical cp-even phases. the first ones are t̂-odd angular asymmetries that are not proportional to a t̂-odd initial-state polarisation component pz. the second ones are t̂-even angular asymmetries proportional to pz. the latter do obvi- ously not appear in the decay of spinless particles and are, on the other hand, the only way to access imaginary parts of decay amplitude interferences in the three-body decays of spin- ning particles (with unmeasured final-state spins). conversely, it was stressed that some t̂-odd angular asymmetries only give access to imaginary parts of production amplitude interferences, not to decay ones. the t̂-odd angular asymmetries sensitive to imaginary parts of production amplitude interferences could serve to verify the assumption of cp conservation in production, without relying on nonvanishing differences of cp-even phases between either production or decay amplitudes. so eventually, comparing the measured patterns of asymmetries with the expectations provided here for specific resonant interme- diate states could allow to decrypt the dynamical nature of the process scrutinized. acknowledgements i am grateful to yuval grossman and maurizio martinelli for discussions on the topic treated here. together with christophe grojean they also provided much valued comments on the manuscript of this paper. a appendix we present below the distributions obtained by relaxing the hypotheses made in the main text. when parity is violated in the production of particle , its px and py polarisation components can be nonvanishing. in three-body decays with a massive vector b appearing in the final state, the a± amplitudes for which λb = can also be nonvanishing. moreover, in the b → / / decay, parity violation and massive , fermions respectively produces terms proportional to: αb ≡ |mb(+ / ,− / )| −|mb(− / , + / )| |mb(+ / ,− / )| + |mb(− / , + / )| , and µb ≡ |mb(+ / , + / )| + |mb(− / ,− / )| |mb(+ / ,− / )| + |mb(− / , + / )| . tables to respectively extend tables to with these additional contributions to the kinematic distributions. there, we used the (p̃x, p̃y, p̃z) ≡ r(φ,θ, )t (px,py,pz) polarisa- – – tions along the xa, ya, and za directions: p̃xp̃y p̃z   =  cos θ cos φ cos θ sin φ −sin θ−sin φ cos φ sin θ cos φ sin θ sin φ cos θ    pxpy pz   . referring to section where the discrete symmetry properties of the different quantities above were derived, one sees that p̃x is p-even–t̂-odd while p̃y and p̃z are both p-odd–t̂- even. references [ ] m. vieites díaz, charmless two-body b-meson decays at lhcb, presentation at the ichep conference on august , , in chicago . 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[ ] m. gronau and j. l. rosner, triple product asymmmetries in Λb and Ξb decays, phys. lett. b ( ) – , [ . ]. http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /j.nuclphysbps. . . http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . / - / / / http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /s x http://dx.doi.org/ . /s x http://arxiv.org/abs/ . http://dx.doi.org/ . /j.physletb. . . http://dx.doi.org/ . /j.physletb. . . http://arxiv.org/abs/ . + / ( |a+| −|a−| ) + ( |a+| + |a−| ) p̃z ( sin θb + cos θbµb ) cos θaαa + / ( |a+| −|a−| ) p̃z + ( |a+| + |a−| ) ( sin θb + cos θbµb ) − / ( |b+| −|b−| ) p̃z − ( |b+| + |b−| ) cos θa cos θbαaαb + ( + sin θbµb + cos θb ) + / ( |b+| −|b−| ) − ( |b+| + |b−| ) p̃z cos θbαb + ( + sin θbµb + cos θb ) cos θaαa + re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa ( sin θb + cos θbµb ) sin θaαa + / √ ( re { a∗+b+ } − re { a∗−b− }) p̃x − ( im { a∗+b+ } + im { a∗−b− }) p̃y cos φb cos θa sin θbαaαb + ( − µb ) sin θb + / √ ( re { a∗+b+ } + re { a∗−b− }) p̃x − ( im { a∗+b+ } − im { a∗−b− }) p̃y cos φb sin θbαb + ( − µb ) cos θa sin θbαa + / re { b∗+b− } p̃x + im { b∗+b− } p̃y cos ( φa + φb ) ( − µb ) sin θa sin θbαa − / √ ( re { a∗+b− } − re { a∗−b+ }) + ( re { a∗+b− } + re { a∗−b+ }) p̃z cos ( φa + φb ) ( − µb ) sin θa sin θbαa + / √ ( re { a∗+b− } − re { a∗−b+ }) p̃z + ( re { a∗+b− } + re { a∗−b+ }) cos ( φa + φb ) sin θa sin θbαaαb + re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa ( sin θb + cos θbµb ) sin θaαa − / √ ( re { a∗+b+ } − re { a∗−b− }) p̃y + ( im { a∗+b+ } + im { a∗−b− }) p̃x sin φb cos θa sin θbαaαb + ( − µb ) sin θb − / √ ( re { a∗+b+ } + re { a∗−b− }) p̃y + ( im { a∗+b+ } − im { a∗−b− }) p̃x sin φb sin θbαb + ( − µb ) cos θa sin θbαa − / re { b∗+b− } p̃y − im { b∗+b− } p̃x sin ( φa + φb ) ( − µb ) sin θa sin θbαa − / √ ( im { a∗+b− } − im { a∗−b+ }) p̃z + ( im { a∗+b− } + im { a∗−b+ }) sin ( φa + φb ) ( − µb ) sin θa sin θbαa + / √ ( im { a∗+b− } − im { a∗−b+ }) + ( im { a∗+b− } + im { a∗−b+ }) p̃z sin ( φa + φb ) sin θa sin θbαaαb table . all contributions to / → a / b → / / / angular distribution which appear when the assumptions leading to table are relaxed, so that px, py, αb or µb defined in the text are nonvanishing. we have defined (p̃x, p̃y, p̃z ) ≡ r(φ,θ, )t (px,py,pz ). − / ( |a+| −|a−| ) + ( |a+| + |a−| ) p̃z ( sin θb + cos θbµb )( − cos θa ) cos θaαa + / ( |a+| −|a−| ) p̃z + ( |a+| + |a−| ) ( sin θb + cos θbµb )( + cos θa ) + / ( |b+| − |b−| −|c+| + |c−| ) − ( |b+| + |b−| + |c+| + |c−| ) p̃z ( + sin θbµb + cos θb ) cos θaαa − / ( |b+| −|b−| + |c+| −|c−| ) p̃z − ( |b+| + |b−| −|c+| −|c−| ) ( + sin θbµb + cos θb ) cos θa − / ( |b+| − |b−| − |c+| + |c−| ) − ( |b+| + |b−| + |c+| + |c−| ) p̃z ( + sin θbµb + cos θb ) cos θaαa − / ( |b+| −|b−| − |c+| + |c−| ) p̃z − ( |b+| + |b−| + |c+| + |c−| ) ( + sin θbµb + cos θb ) − / ( |b+| − |b−| + |c+| −|c−| ) p̃z − ( |b+| + |b−| −|c+| −|c−| ) cos θa cos θbαaαb + / ( |b+| −|b−| −|c+| + |c−| ) − ( |b+| + |b−| + |c+| + |c−| ) p̃z cos θa cos θbαb + / ( |b+| − |b−| + |c+| − |c−| ) p̃z − ( |b+| + |b−| − |c+| − |c−| ) cos θa cos θbαaαb + / ( |b+| −|b−| + |c+| − |c−| ) − ( |b+| + |b−| − |c+| − |c−| ) p̃z cos θbαb − / re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa ( sin θb + cos θbµb )( − cos θa ) sin θaαa − √ / ( re { b∗+c+ } − re { b∗−c− }) p̃x + ( im { b∗+c+ } + im { b∗−c− }) p̃y cos φa ( + sin θbµb + cos θb ) sin θa − ( − cos θa ) sin θa cos θbαaαb − √ / ( re { b∗+c+ } + re { b∗−c− }) p̃x + ( im { b∗+c+ } − im { b∗−c− }) p̃y cos φa sin θa cos θbαb − ( + sin θbµb + cos θb )( − cos θa ) sin θaαa − / √ ( re { a∗+b+ } + re { a∗−b− }) p̃x − ( im { a∗+b+ } − im { a∗−b− }) p̃y cos φb ( − µb )( − cos θa ) cos θa sin θbαa − ( + cos θa ) sin θbαb + / √ ( re { a∗+b+ } − re { a∗−b− }) p̃x − ( im { a∗+b+ } + im { a∗−b− }) p̃y cos φb ( − µb )( + cos θa ) sin θb − ( − cos θa ) cos θa sin θbαaαb − / re { c∗+c− } p̃x − im { c∗+c− } p̃y cos ( φa + φb ) ( − µb ) sin θ a sin θbαa + √ / ( re { b∗+c− } − re { b∗−c+ }) − ( re { b∗+c− } + re { b∗−c+ }) p̃z cos ( φa + φb ) ( − µb ) sin θ a cos θa sin θbαa + √ / ( re { b∗+c− } − re { b∗−c+ }) p̃z − ( re { b∗+c− } + re { b∗−c+ }) cos ( φa + φb ) ( − µb ) sin θ a sin θb + √ / / ( re { a∗+c− } − re { a∗−c+ }) p̃x − ( im { a∗+c− } + im { a∗−c+ }) p̃y cos ( φa + φb ) sin θ a cos θa sin θbαaαb + ( − µb ) sin θ a sin θb − √ / / ( re { a∗+c− } + re { a∗−c+ }) p̃x − ( im { a∗+c− } − im { a∗−c+ }) p̃y cos ( φa + φb ) sin θ a sin θbαb + ( − µb ) sin θ a cos θa sin θbαa − / re { b∗+b− } p̃x + im { b∗+b− } p̃y cos ( φa + φb ) ( − µb )( − cos θa ) sin θa sin θbαa − / √ ( re { a∗+b− } − re { a∗−b+ }) p̃z + ( re { a∗+b− } + re { a∗−b+ }) cos ( φa + φb ) ( − cos θa ) sin θa sin θbαaαb + / √ ( re { a∗+b− } − re { a∗−b+ }) + ( re { a∗+b− } + re { a∗−b+ }) p̃z cos ( φa + φb ) ( − µb )( − cos θa ) sin θa sin θbαa − √ / / ( re { a∗+c+ } − re { a∗−c− }) p̃z + ( re { a∗+c+ } + re { a∗−c− }) cos ( φa + φb ) ( − µb ) sin θa sin θb − ( − cos θa ) sin θa sin θbαaαb − √ / / ( re { a∗+c+ } − re { a∗−c− }) + ( re { a∗+c+ } + re { a∗−c− }) p̃z cos ( φa + φb ) sin θa sin θbαb − ( − µb )( − cos θa ) sin θa sin θbαa − / re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa ( sin θb + cos θbµb )( − cos θa ) sin θaαa − √ / ( re { b∗+c+ } − re { b∗−c− }) p̃y − ( im { b∗+c+ } + im { b∗−c− }) p̃x sin φa ( + sin θbµb + cos θb ) sin θa − ( − cos θa ) sin θa cos θbαaαb − √ / ( re { b∗+c+ } + re { b∗−c− }) p̃y − ( im { b∗+c+ } − im { b∗−c− }) p̃x sin φa sin θa cos θbαb − ( + sin θbµb + cos θb )( − cos θa ) sin θaαa + / √ ( re { a∗+b+ } + re { a∗−b− }) p̃y + ( im { a∗+b+ } − im { a∗−b− }) p̃x sin φb ( − µb )( − cos θa ) cos θa sin θbαa − ( + cos θa ) sin θbαb − / √ ( re { a∗+b+ } − re { a∗−b− }) p̃y + ( im { a∗+b+ } + im { a∗−b− }) p̃x sin φb ( − µb )( + cos θa ) sin θb − ( − cos θa ) cos θa sin θbαaαb − / re { c∗+c− } p̃y + im { c∗+c− } p̃x sin ( φa + φb ) ( − µb ) sin θ a sin θbαa − √ / ( im { b∗+c− } − im { b∗−c+ }) p̃z − ( im { b∗+c− } + im { b∗−c+ }) sin ( φa + φb ) ( − µb ) sin θ a cos θa sin θbαa − √ / ( im { b∗+c− } − im { b∗−c+ }) − ( im { b∗+c− } + im { b∗−c+ }) p̃z sin ( φa + φb ) ( − µb ) sin θ a sin θb + √ / / ( re { a∗+c− } − re { a∗−c+ }) p̃y + ( im { a∗+c− } + im { a∗−c+ }) p̃x sin ( φa + φb ) sin θ a cos θa sin θbαaαb + ( − µb ) sin θ a sin θb − √ / / ( re { a∗+c− } + re { a∗−c+ }) p̃y + ( im { a∗+c− } − im { a∗−c+ }) p̃x sin ( φa + φb ) sin θ a sin θbαb + ( − µb ) sin θ a cos θa sin θbαa + / re { b∗+b− } p̃y − im { b∗+b− } p̃x sin ( φa + φb ) ( − µb )( − cos θa ) sin θa sin θbαa − / √ ( im { a∗+b− } − im { a∗−b+ }) + ( im { a∗+b− } + im { a∗−b+ }) p̃z sin ( φa + φb ) ( − cos θa ) sin θa sin θbαaαb + / √ ( im { a∗+b− } − im { a∗−b+ }) p̃z + ( im { a∗+b− } + im { a∗−b+ }) sin ( φa + φb ) ( − µb )( − cos θa ) sin θa sin θbαa + √ / / ( im { a∗+c+ } − im { a∗−c− }) + ( im { a∗+c+ } + im { a∗−c− }) p̃z sin ( φa + φb ) ( − µb ) sin θa sin θb − ( − cos θa ) sin θa sin θbαaαb + √ / / ( im { a∗+c+ } − im { a∗−c− }) p̃z + ( im { a∗+c+ } + im { a∗−c− }) sin ( φa + φb ) sin θa sin θbαb − ( − µb )( − cos θa ) sin θa sin θbαa table . same as table , for the / → a / b → / / / process in which particle a has spin / instead of / . this table generalises table . + ( |a+| −|a−| ) + ( |a+| + |a−| ) p̃z cos θa cos θbαa + / ( |b+| −|b−| ) − ( |b+| + |b−| ) p̃z cos θa sin θbαa + ( |a+| −|a−| ) p̃z + ( |a+| + |a−| ) cos θb − / ( |b+| −|b−| ) p̃z − ( |b+| + |b−| ) sin θb + re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa sin θa cos θbαa − / √ ( re { a∗+b+ } − re { a∗−b− }) p̃x − ( im { a∗+b+ } + im { a∗−b− }) p̃y cos φb sin θb − / √ ( re { a∗+b+ } + re { a∗−b− }) p̃x − ( im { a∗+b+ } − im { a∗−b− }) p̃y cos φb cos θa sin θbαa − re { b∗+b− } p̃x + im { b∗+b− } p̃y cos ( φa + φb ) sin θa sin θbαa + / √ ( re { a∗+b− } − re { a∗−b+ }) + ( re { a∗+b− } + re { a∗−b+ }) p̃z cos ( φa + φb ) sin θa sin θbαa + re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa sin θa cos θbαa + / √ ( re { a∗+b+ } − re { a∗−b− }) p̃y + ( im { a∗+b+ } + im { a∗−b− }) p̃x sin φb sin θb + / √ ( re { a∗+b+ } + re { a∗−b− }) p̃y + ( im { a∗+b+ } − im { a∗−b− }) p̃x sin φb cos θa sin θbαa + re { b∗+b− } p̃y − im { b∗+b− } p̃x sin ( φa + φb ) sin θa sin θbαa + / √ ( im { a∗+b− } − im { a∗−b+ }) p̃z + ( im { a∗+b− } + im { a∗−b+ }) sin ( φa + φb ) sin θa sin θbαa table . all contributions to / → a / b → / angular distribution which appear with the assumptions leading to table are relaxed, so that px and py are nonvanishing. we have defined (p̃x, p̃y, p̃z ) ≡ r(φ,θ, )t (px,py,pz ). − / ( |a+| −|a−| ) + ( |a+| + |a−| ) p̃z ( − cos θa ) cos θa cos θbαa + / ( |a+| −|a−| ) p̃z + ( |a+| + |a−| ) ( + cos θa ) cos θb + / ( |b+| − |b−| −|c+| + |c−| ) − ( |b+| + |b−| + |c+| + |c−| ) p̃z cos θa sin θbαa − / ( |b+| −|b−| + |c+| −|c−| ) p̃z − ( |b+| + |b−| −|c+| −|c−| ) cos θa sin θb − / ( |b+| − |b−| − |c+| + |c−| ) − ( |b+| + |b−| + |c+| + |c−| ) p̃z cos θa sin θbαa − / ( |b+| −|b−| − |c+| + |c−| ) p̃z − ( |b+| + |b−| + |c+| + |c−| ) sin θb + √ / ( re { b∗+c+ } + re { b∗−c− }) p̃x + ( im { b∗+c+ } − im { b∗−c− }) p̃y cos φa ( − cos θa ) sin θa sin θbαa − re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa ( − cos θa ) sin θa cos θbαa − √ / ( re { b∗+c+ } − re { b∗−c− }) p̃x + ( im { b∗+c+ } + im { b∗−c− }) p̃y cos φa sin θa sin θb + / √ ( re { a∗+b+ } + re { a∗−b− }) p̃x − ( im { a∗+b+ } − im { a∗−b− }) p̃y cos φb ( − cos θa ) cos θa sin θbαa − / √ ( re { a∗+b+ } − re { a∗−b− }) p̃x − ( im { a∗+b+ } + im { a∗−b− }) p̃y cos φb ( + cos θa ) sin θb + / re { c∗+c− } p̃x − im { c∗+c− } p̃y cos ( φa + φb ) sin θ a sin θbαa − √ / ( re { b∗+c− } − re { b∗−c+ }) − ( re { b∗+c− } + re { b∗−c+ }) p̃z cos ( φa + φb ) sin θ a cos θa sin θbαa − √ / ( re { b∗+c− } − re { b∗−c+ }) p̃z − ( re { b∗+c− } + re { b∗−c+ }) cos ( φa + φb ) sin θ a sin θb + √ / / ( re { a∗+c− } + re { a∗−c+ }) p̃x − ( im { a∗+c− } − im { a∗−c+ }) p̃y cos ( φa + φb ) sin θ a cos θa sin θbαa − √ / / ( re { a∗+c− } − re { a∗−c+ }) p̃x − ( im { a∗+c− } + im { a∗−c+ }) p̃y cos ( φa + φb ) sin θ a sin θb + / re { b∗+b− } p̃x + im { b∗+b− } p̃y cos ( φa + φb ) ( − cos θa ) sin θa sin θbαa − √ / / ( re { a∗+c+ } − re { a∗−c− }) + ( re { a∗+c+ } + re { a∗−c− }) p̃z cos ( φa + φb ) ( − cos θa ) sin θa sin θbαa − / √ ( re { a∗+b− } − re { a∗−b+ }) + ( re { a∗+b− } + re { a∗−b+ }) p̃z cos ( φa + φb ) ( − cos θa ) sin θa sin θbαa + √ / / ( re { a∗+c+ } − re { a∗−c− }) p̃z + ( re { a∗+c+ } + re { a∗−c− }) cos ( φa + φb ) sin θa sin θb + √ / ( re { b∗+c+ } + re { b∗−c− }) p̃y − ( im { b∗+c+ } − im { b∗−c− }) p̃x sin φa ( − cos θa ) sin θa sin θbαa − re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa ( − cos θa ) sin θa cos θbαa − √ / ( re { b∗+c+ } − re { b∗−c− }) p̃y − ( im { b∗+c+ } + im { b∗−c− }) p̃x sin φa sin θa sin θb − / √ ( re { a∗+b+ } + re { a∗−b− }) p̃y + ( im { a∗+b+ } − im { a∗−b− }) p̃x sin φb ( − cos θa ) cos θa sin θbαa + / √ ( re { a∗+b+ } − re { a∗−b− }) p̃y + ( im { a∗+b+ } + im { a∗−b− }) p̃x sin φb ( + cos θa ) sin θb + / re { c∗+c− } p̃y + im { c∗+c− } p̃x sin ( φa + φb ) sin θ a sin θbαa + √ / ( im { b∗+c− } − im { b∗−c+ }) p̃z − ( im { b∗+c− } + im { b∗−c+ }) sin ( φa + φb ) sin θ a cos θa sin θbαa + √ / ( im { b∗+c− } − im { b∗−c+ }) − ( im { b∗+c− } + im { b∗−c+ }) p̃z sin ( φa + φb ) sin θ a sin θb + √ / / ( re { a∗+c− } + re { a∗−c+ }) p̃y + ( im { a∗+c− } − im { a∗−c+ }) p̃x sin ( φa + φb ) sin θ a cos θa sin θbαa − √ / / ( re { a∗+c− } − re { a∗−c+ }) p̃y + ( im { a∗+c− } + im { a∗−c+ }) p̃x sin ( φa + φb ) sin θ a sin θb − / re { b∗+b− } p̃y − im { b∗+b− } p̃x sin ( φa + φb ) ( − cos θa ) sin θa sin θbαa + √ / / ( im { a∗+c+ } − im { a∗−c− }) p̃z + ( im { a∗+c+ } + im { a∗−c− }) sin ( φa + φb ) ( − cos θa ) sin θa sin θbαa − / √ ( im { a∗+b− } − im { a∗−b+ }) p̃z + ( im { a∗+b− } + im { a∗−b+ }) sin ( φa + φb ) ( − cos θa ) sin θa sin θbαa − √ / / ( im { a∗+c+ } − im { a∗−c− }) + ( im { a∗+c+ } + im { a∗−c− }) p̃z sin ( φa + φb ) sin θa sin θb table . same as table , for the / → a / b → / process, in which particle a has spin / instead of / . this table generalises table . + ( |a+| −|a−| −|b+| + |b−| ) p̃z + ( |a+| + |a−| + |b+| + |b−| ) + ( |a+| −|a−| + |b+| −|b−| ) + ( |a+| + |a−| −|b+| −|b−| ) p̃z cos θaαa + re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa sin θaαa + re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa sin θaαa table . all contributions to / → a / b → / b angular distribution which appear when the assumptions leading to table are relaxed, so that a±, px, py defined in the text are nonvanishing. + / ( |a+| −|a−| −|b+| + |b−| + |c+| − |c−| ) p̃z + ( |a+| + |a−| + |b+| + |b−| + |c+| + |c−| ) + / ( |a+| − |a−| + |b+| − |b−| −|c+| + |c−| ) + ( |a+| + |a−| − |b+| − |b−| −|c+| −|c−| ) p̃z cos θaαa + / ( |a+| −|a−| −|b+| + |b−| −|c+| + |c−| ) p̃z + ( |a+| + |a−| + |b+| + |b−| −|c+| −|c−| ) cos θa − / ( |a+| − |a−| + |b+| − |b−| − |c+| + |c−| ) + ( |a+| + |a−| − |b+| − |b−| − |c+| − |c−| ) p̃z cos θaαa + √ ( re { b∗+c+ } + re { b∗−c− }) p̃x + ( im { b∗+c+ } − im { b∗−c− }) p̃y cos φa ( − cos θa ) sin θaαa − re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa ( − cos θa ) sin θaαa − √ ( re { b∗+c+ } − re { b∗−c− }) p̃x + ( im { b∗+c+ } + im { b∗−c− }) p̃y cos φa cos θa sin θa + √ ( re { b∗+c+ } + re { b∗−c− }) p̃y − ( im { b∗+c+ } − im { b∗−c− }) p̃x sin φa ( − cos θa ) sin θaαa − re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa ( − cos θa ) sin θaαa − √ ( re { b∗+c+ } − re { b∗−c− }) p̃y − ( im { b∗+c+ } + im { b∗−c− }) p̃x sin φa cos θa sin θa table . same as table , for the / → a / b → / b process, in which particle a has spin / instead of / . this table generalises table . + ( |a+| −|a−| ) p̃z + ( |a+| + |a−| ) + ( |a+| −|a−| ) + ( |a+| + |a−| ) p̃z cos θaαa + re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa sin θaαa + re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa sin θaαa table . all contributions to / → a / b → / b angular distribution which appear when the assumptions leading to table are relaxed, so that px, py defined in the text are nonvanishing. − / ( |a+| −|a−| ) + ( |a+| + |a−| ) p̃z ( − cos θa ) cos θaαa + / ( |a+| −|a−| ) p̃z + ( |a+| + |a−| ) ( + cos θa ) − re { a∗+a− } p̃x − im { a∗+a− } p̃y cos φa ( − cos θa ) sin θaαa − re { a∗+a− } p̃y + im { a∗+a− } p̃x sin φa ( − cos θa ) sin θaαa table . same as table for the / → a / b → / b process, in which particle a has spin / instead of / . this table generalises table . introduction angular distributions discrete symmetry properties asymmetries . -odd angular asymmetries . -even angular asymmetries summary a appendix j h e p ( ) published for sissa by springer received: may , revised: july , accepted: july , published: august , beautiful mirrors at the lhc kunal kumar,a,b william shepherd,b,c tim m.p. taita,b,c and roberto vega-moralesa,b ahep division, argonne national lab, argonne il , u.s.a. bnorthwestern university, sheridan road, evanston, il , u.s.a. cdepartment of physics and astronomy, university of california, irvine, ca , u.s.a. e-mail: kkumar@u.northwestern.edu, shepherd.william@uci.edu, ttait@uci.edu, robertovegamorales @u.northwestern.edu abstract: we explore the “beautiful mirrors” model, which aims to explain the measured value of abf b, discrepant at the . σ level. this scenario introduces vector-like quarks which mix with the bottom, subtly affecting its coupling to the z. the spectrum of the new particles consists of two bottom-like quarks and a charge − / quark, all of which have electroweak interactions with the third generation. we explore the phenomenology and discovery reach for these new particles at the lhc, exploring single mirror quark production modes whose rates are proportional to the same mixing parameters which resolve the abf b anomaly. we find that for mirror quark masses . gev, a tev lhc with fb− is required to reasonably establish the scenario and extract the relevant mixing parameters. keywords: beyond standard model, quark masses and sm parameters, hadronic col- liders arxiv eprint: . open access doi: . /jhep ( ) mailto:kkumar@u.northwestern.edu mailto:shepherd.william@uci.edu mailto:ttait@uci.edu mailto:robertovegamorales @u.northwestern.edu http://arxiv.org/abs/ . http://dx.doi.org/ . /jhep ( ) j h e p ( ) contents introduction z boson couplings to bottom quarks beautiful mirrors . mixing and the mass eigenstates . higgs couplings . w and z couplings . sample parameters mirror quark phenomenology at the lhc . mirror quark production and decay . χ production . single b /b production . electroweak b − χ production conclusions introduction the primary mission of the large hadron collider (lhc) is to seek evidence for the break- down of the standard model (sm) [ ]. for the most part, the sm with a light higgs provides a very accurate description of the observed data coming from a wide variety of experiments. while deviations from the sm have come (and mostly gone), most disappear as statistics and experimental precision increases and theoretical inputs improve. the agreement be- tween the sm predictions and experiment is unprecedented, particularly in the arena of precision electroweak measurements, many of which have per mil level uncertainties [ ]. however, there is one notable exception. the forward-backward asymmetry of the bottom quark (abf b) shows roughly a . σ deviation from the value predicted by a best fit to precision data within the sm [ ]. while not in itself very significant, this deviation has persisted for more than a decade and may be a guide to what the lhc could find. abf b further plays an interesting role in the global fit to precision data, which in the context of the sm provides the indirect constraints on the higgs mass [ , ]. indeed, the poor fit to abf b can be understood as a tension in the preferred value of mh between the leptonic observables, which prefer mh ∼ gev and abf b which prefers values closer to ∼ tev. it is interesting that recent tevatron measurements also show an unexpected asymmetry in top quark pair production [ – ], though existing proposed new physics explanations do not typically correlate this with any particular effect on abf b [ – ]. – – j h e p ( ) the fit has settled into an “unhappy” middle ground between the two, favoring the other measurements at the cost of disagreeing with the observed abf b. as a result, if one simply ignores abf b, one gets a fit to mh which is marginally at odds with the direct search bound from lep-ii [ ]. broadly defined, there are three attitudes one can take toward abf b and the preci- sion data: • one can assume abf b is a statistical (or unaccounted for systematic) effect and that reasonable variations of the other measured precision observables explain the tension between the sm fit to the higgs mass and direct searches. • one can consider the possibility that abf b itself does not reflect the presence of new physics, but accidently makes the sm fit to mh more palatable than it would otherwise have been. in this case, one can invoke new physics contributions to the peskin and takeuchi t parameter [ ] which may reconcile the indirect bounds on mh with the direct search limits (for a few examples, see [ – ]). • one can take the attitude that the bottom quark couplings to the z boson may themselves reflect the presence of new physics [ – ]. in this article, we will take the last approach, and explore the consequences of one particular model of this kind, the “beautiful mirrors” model [ ], which introduces new physics to produce the observed anomaly in abf b. the beautiful mirrors model works by introducing a new set of vector-like (or “mir- ror”) quarks, which mix with the bottom quark, adjusting its coupling to the z. vector-like quarks are chosen so that gauge anomalies are trivially evaded, and the requirement that there be no source of ewsb other than the sm higgs (motivated to avoid tree-level con- tributions to the oblique electroweak parameters) restricts the su( ) representations of the mirror quarks to singlets, triplets, and doublets. in [ ], two versions of the doublet model were explored. the desired shift in the z couplings to bottom quarks may be ef- fected for mirror quark quantum numbers under (su( ), su( ), u( )) given by ( , , / ) or ( , ,− / ). the first option looks like a vector-like fourth sm generation, and requires mirror quark masses . gev and sm higgs mass mh & gev in order to fit the lep data. its detailed phenomenology was explored in ref. [ , ]. the null results for direct searches for the mirror quarks [ ] have severely restricted the parameter space of this model, leading us to consider the more exotic representation ( , ,− / ), which contains a bottom-like mirror quark ω and its electroweak partner, an electrically charged − / quark, χ. the precision data favors the masses for these “exotic mirrors” to be & gev [ ], making them perfect targets for a discovery at the lhc. in this paper we explore the phenomenological consequences of the exotic mirrors model at the lhc. we begin in section by revisiting the target z-b-b couplings, which helps pin down the amount of mixing required when we discuss the beautiful mirrors model itself in section . lhc signals and strategies to establish a given signal as arising from the mirror quark solution to the abf b puzzle are presented in section . we conclude in section . – – j h e p ( ) - . - . - . - . - . - . - . - . - . . . . . . . . r gδ l gδ . . . . . . - . . . . . . . . r gδ l gδ figure . the regions in the z-b-b coupling parameter space favored by ew precision data. the inner (outer) shaded regions correspond to σ ( σ) agreement with the best fit shifts in the left- and right-handed couplings. z boson couplings to bottom quarks in this section, we examine the ranges of values of the z-b-b couplings consistent with precision electroweak data. modifications to bottom couplings must be applied subtly. while abf b is discrepant as described above, the branching ratio of z bosons decaying into bb (which is usually reported as a ratio between the decay to bottom quarks and into all hadrons, rb ≡ Γ(z → bb)/Γ(z → hadrons)) shows no large deviation [ ]. in addition, as discussed in [ ], there is data from off of the z-pole which, while less precise than the z-pole measurements, implies important constraints on the signs of the couplings. in particular, the off-pole data requires that the left-handed interaction be close to the sm value, but does not restrict the sign of the right-handed value. since together abf b and rb restrict the magnitude of the couplings, the allowed space of couplings lies within two disjoint regions of parameter space. to explore the allowed regions of coupling space, we allow shifts in the left- and right- handed z-b-b interactions by δgl and δgr, respectively. we include these parameters in a global fit to the precision data, including the tevatron measurements of the top and w masses [ , ]. we marginalize over αem , αs, mt, mz , and mh, in particular allowing mh to take any value consistent with the direct search limit from lep-ii [ ]. we assume there are no large additional contributions to the oblique parameters s and t beyond those which result from varying the top and higgs masses. the results of the fit are presented in figure , which indicates that the data favors small (∼ − ) corrections to the left-handed coupling and more large (either ∼ + − or ∼ − . ) shifts in δgr. the values of δgr and δgl should be highly correlated with one another, in order to result in the necessary correction to abf b, while the maximum and minimum changes are set by rb. note that the assumption of no large additional contributions to the s and t parameters is consistent with the exotic mirror scenario, but not with standard mirror quarks. – – j h e p ( ) beautiful mirrors the exotic beautiful mirrors model extends the standard model by introducing two sets of vector-like quarks, Ψl,r with quantum numbers ( , ,− / ) and ξl,r with quantum numbers ( , ,− / ). in terms of its su( ) components, Ψ decomposes as, Ψl,r = ( ωl,r χl,r ) ( . ) where ω is a charge − / quark and χ has charge − / . introducing vector-like quarks allows for new flavor mixing, which we will ultimately invoke to explain the measured value of abf b. among other effects, this mixing can lead to right handed w couplings and tree level flavor changing interactions with the z and higgs. we assume for simplicity that the exotic quarks only couple to the third generation sm quarks, as z couplings to the two light generations appear to agree with sm predictions and any corrections are thus constrained to be small. allowing for substantial mixing between the mirror quarks and the two lighter sm generations will generate tree level fcnc interactions which can contribute to b → sγ [ – ] which is highly constrained. in addition, mixing with the light quarks leads to interactions of the type z-b-s, z-b-d, and z-s-d, as well as one loop box diagrams (with the mirror quark running in the loop), contributing to b-b [ – ] and possibly k-k and d-d mixing [ ], all of which lead to tight constraints. these interactions are additionally constrained by rare decay processes of the strange and bottom mesons [ – ], as well as b and k meson decays such as b → ℓ+ℓ−x, b → j/ψks and k → πνν [ – ]. that said, provided the mixing is small enough, the presence of such mixing between the mirror quarks and the first- and second-generation fermions (perhaps motivated by minimal flavor violation [ – ]) would not much affect the parameter space or resulting phenomenology. the choice of exotic mirrors (as opposed to the standard mirror gauge assignment) induces no right-handed w-t-b interaction, evading potentially strong bounds again coming from b → sγ [ ]. . mixing and the mass eigenstates electroweak symmetry breaking (ewsb) occurs as in the sm through the vacuum expec- tation value of a higgs scalar, Φ. we assume that the sm higgs is the only source of ewsb, and write down the complete set of interactions between the mirror quarks and the third generation sm quarks, as allowed by su( ) × su( ) × u( ) gauge invariance. in addition, the vector quarks have dirac masses, whose magnitudes are not dictated by ewsb, but we will assume are at the ∼ tev scale. such mass terms are protected by chiral symmetries, and thus technically natural in the sense of ’t hooft [ ]. the complete set of yukawa interactions and masses involving the mirror quarks are, lmass = −y q ′ lΦb ′ r−yrΨ ′ lΦ̃b ′ r−ylq ′ lΦξ ′ r−y Ψ ′ lΦ̃ξ ′ r−m Ψ ′ lΨ ′ r−m ξ ′ lξ ′ r + h.c. ( . ) where the primed fields refer to gauge (as opposed to mass) eigenstates and q′l refers to the third generation quark doublet and b′r is the third generation down-type singlet. – – j h e p ( ) after symmetry breaking, the couplings are most transparent in the unitary gauge, Φ = √ ( v + h) t , where v ∼ gev is the ewsb vacuum expectation value and h is the higgs boson. the mass and mixing terms of the lagrangian may be written in matrix form, lmass = −d ′ l ( md + h v nd ) d ′ r + h.c. ( . ) where d′ l,r = (bl,r,ωl,r,ξl,r) are vectors in flavor space. md is the bottom sector mass matrix, md =        y yl yr m y m        ( . ) where yi = yiv/ √ . nd/v is the coupling matrix between the real higgs and the down type quarks, nd =        y yl yr y        . ( . ) to diagonalize the mass matrix we rotate by unitary matrices ud and wd which trans- form the left- and right-handed gauge eigenstates into the corresponding mass eigenstates (denoted by unprimed vectors in flavor space, dl,r). we parametrize these matrices ud =        cl cl sl cl sl −sl cl − cl sl sl cl cl − sl sl sl sl cl sl sl − cl cl sl −cl sl − sl cl sl cl cl        ( . ) where cl ≡ cos θl and so on, and with an analogous expression for wd with θ l ij → θrij . we have set potential phases to zero for simplicity; their inclusion will complicate the analysis slightly but are not expected to shed much light on the abf b puzzle. these matrices transform the gauge eigenstates to mass eigenstates, d ′ l = ud dl , d ′ r = wd dr . ( . ) – – j h e p ( ) the requirement that these transformations produce the mass eigenbasis requires ud † mdwd =        m m m        . ( . ) for values of the mixing which are phenomenologically viable, b is predominantly the original sm bottom quark fields, b is mostly ω and b is mostly ξ. the eigenvalues m ≡ mb, m , and m are the bottom quark mass, and two exotic quark masses, respectively. note that we do not necessarily order the exotic quarks b , by mass. . higgs couplings the higgs couplings are complicated by the fact that the mass matrix receives contribu- tions from the vector-like masses m and m , resulting in flavor-violating higgs couplings between the three mass eigenstate quarks, lhq = − h v d vdpr d + h.c. ( . ) where vd = u † d ndwd. the off diagonal entries of vd will lead to tree level flavor changing couplings between the higgs of the form h-b -b , etc. such couplings allow for decays of the heavy quarks into a bottom quark and a higgs, as discussed below. . w and z couplings we now examine the modifications to the w and z couplings coming from the mixing of the bottom quark with the exotics. in the mass basis there are w couplings of the form lw = g √ w−µ [ χγµ ( u j d pl + w j d pr ) d j + d i γµu i∗d plt ] + h.c. ( . ) where g = e/ cos θw as usual. the couplings between the z and the down-type quarks may be written in matrix form, lz = g cos θw zµdγ µ (lpl + rpr) d + h.c. ( . ) where l = u † d gl ud, ( . ) r = w † d gr wd, ( . ) and the gl,r are diagonal matrices in the gauge basis with left and right-handed couplings of the down-type quarks to the z boson as their entries, gl = diag ( − + sin θw, + sin θw, sin θw ) , ( . ) gr = diag ( sin θw, + sin θw, sin θw ) . ( . ) – – j h e p ( ) our primary concern is to modify the b-quark couplings wth the z, in order to explain the measured abf b while remaining consistent with rb. these couplings are determined by the entries of the l and r matrices. in terms of the parameterization, eq. ( . ), these entries are, l = gl ( cl c l ) + gl ( −sl c l − s l s l c l ) + gl ( sl s l − s l c l c l ) , r = gr ( cr c r ) + gr ( −sr c r − s r s r c r ) + gr ( sr s r − s r c r c r ) .( . ) these expressions may be simplified by noting that the term proportional to the electric charge is common to all of the diagonal entries of gl,r and thus cancels out of shifts in the coupling, leaving behind only the non-universal terms proportional to t . in terms of the mixing angles, these shifts become, δgbl = g cos θw [ − (cl c l ) + (sl c l + s l s l c l ) ] , δgbr = g cos θw ( sr c r + s r s r c r ) . ( . ) . sample parameters comparing the expressions for the shifts in the z-b-b interactions in equation ( . ) with the results in figure , we can determine relations among the input parameters which will improve the agreement of abf b with its measured value. we will analyze a specific point within this parameter space and examine the collider phenomenology. for simplicity we assume negligible mixing between ω and ξ with sr = . and sl = . and all other mixing angles set to zero. for greater clarity of notation, therefore, we denote these angles simply by sr and sl henceforth. the negligible mixing between ω and ξ means we have chosen y = . the yukawa couplings in the bottom sector mass matrix can be related to the mixing angles in the limit of negligible mb as follows yl ≃ m sl v yr ≃ m sr v ( . ) the mixings which are postulated here yield couplings shifts through equation ( . ) of δgbl = . × − δgbr = . × − ( . ) and were chosen with the intent of simplifying our discussion by removing the mixings not relevant to the measured asymmetry while giving coupling shifts near the center of the favored region. these assumptions leave us with only three free parameters in our system, mb , mb , and mh. the relation between mb and mχ is m χ = m b − y r = mb c r ( . ) as mentioned in [ ] the fit to data is not very sensitive to mb as long as it is below a few tev. looking at the mh − mχ parameter space plot, in the study just mentioned, we choose mh = gev and let the masses mb (or equivalently mχ) and mb vary between gev and tev. these points lie within σ of the best fit point. we study the detailed phenomenology at this point in parameter space, but will note where interesting deviations are possible. – – j h e p ( ) ( fb ) σ mass (gev) qq ) + jets b( single b ) + jets b( single b + jetsχsingle + jetsχsingle = tevcme χ b χ b figure . production cross sections for both single and pair production of mirror quarks, as a function of their masses and for the mixing angles specified in the text. the single b , + jets rates sum both production of b , + jets and b , + jets. for this plot we have chosen mh = gev mirror quark phenomenology at the lhc the key question for the lhc is whether or not the mirror quarks can be discovered, and their su( ) × u( ) gauge representations and mixing angles understood well enough to experimentally connect them to the measured value of abf b. this task is complicated by the fact that the mixing through ewsb itself obscures the original representations of b and b , and the χ, while unusual in that it has charge − / , decays into w−b, looking much like a t′ which produces a “wrong sign” bottom quark in its decay; measuring the charge of the final state b quark is extremely subtle, though perhaps not impossible [ , ]. . mirror quark production and decay the mirror quarks χ, b , and b can be produced either in pairs through qcd, or singly, through the electroweak interaction. single χ quarks are produced through a bq initial state with a t-channel w boson exchanged whereas single b and b arise from a bq initial state with a t-channel z boson (or, to a much smaller degree, higgs boson) exchanged. the – – j h e p ( ) resulting cross sections as a function of the mass of the exotic quark in question are plotted in figure , where we have used the mixing angles appropriate for the sample solution to the abf b puzzle discussed in section . and a higgs mass of gev (although the results are quite robust for larger higgs masses as well). the cross sections have been computed at tree level with the madevent code [ ], using the cteq l parton distribution functions (pdfs) [ ]. as can be seen, for the modest mixing angles favored by abf b, pair production is the dominant mechanism for exotic quark masses below ∼ gev. the difference in rates between single χ (q = − ) and single χ (q = + ) production can be understood from the difference in pdfs of the initial state quarks. the χ, which is primarily produced from an initial state u-quark, is expected to have a higher electroweak production rate than χ which which comes primarily from an initial d-quark. the same trend is familiar from single top production in the standard model. pair production cross sections are not affected by the choice of mixing angles at all, and thus the prediction of that cross section is robust for any point in the parameter space of the exotic mirrors model. single production cross sections are proportional to the square of the relevant mixing angle or combination of mixing angles, and thus those cross sections will be shifted by changes in mixing angles. the χ quark decays with % branching ratio into w−b for our parameter point, appearing as a a t ′ which produces b instead of a b when it decays. as such, it is sensitive to the usual fourth generation t′ searches at the lhc, with an expected reach through pair production of roughly gev [ ] for fb− of integrated luminosity at tev. searches for t′ quarks at the tevatron provide bounds of mχ ≥ gev [ ]. allowing ω − ξ mixing can open additional channels for χ decay such as χ → w−b , subject to kinematic constraints. depending on the size of the mixing this can become comparable in magnitude to the direct decay to purely sm final states. the bottom-like quarks b and b can decay into zbi, hbi (provided the higgs is light enough), wt, and wχ. for our example parameter point, the χ is too heavy to be produced on-shell in decays of b , and b does not have a charged-current coupling to χ due to our choice of no ω − ξ mixing. heavy quark decays into wt are rendered negligible by this assumption as well. thus, these quarks decay only through the fcnc modes, b , → hb, b , → zb. for higgs mass of gev and exotic quark mass of gev, the branching ratios for both b and b are % b , → zb and % b , → hb. note that these branching ratios are insensitive to changes in the mixing angles sl,r, and are not strongly sensitive to increases in exotic quark mass. the z decay mode offers the possibility of lepton pairs in the final state (with modest branching ratio) whereas the h decay mode leads to a b , → bbb final state a large fraction of the time. branching ratios of bi decays are independent of shifts in sl and sr in absence of ω−ξ mixing. this is because in that limit the flavor changing couplings of the higgs and the z both have identical dependence on the mixing angles. if mixing between the new vector- like quarks is allowed it can lead to shifts in the relative branching fractions to z and h – – j h e p ( ) final states, and also opens additional decay channels, such as b → w + χ or b → zb , dependent on kinematic constraints. these will in general lead to more spectacular cascade decays, as the decay product vector quark then further decays to sm fields. while the lhc cannot hope to exclude the entire range of mirror quark masses favored by the electroweak fit, it is sensitive to much of the parameter space. for masses . tev, we can expect based on earlier studies [ ] that by the end-running of the lhc (which we take to be at center-of-mass running of tev and data sets on the order of fb− ), the lhc will have observed the mirror quarks through pair production in the decay modes χ → w−b and b , → zb → ℓ+ℓ−b. we explore several subdominant production processes which can help differentiate the beautiful mirrors model from other models with additional vector- like quarks, and establish the mixing parameters as consistent with a solution to abf b. we choose as a reference value for our studies mirror quark masses m (= mχ) = gev. such masses are consistent with tevatron bounds and within the σ fit to the precision data [ ], and represent a cautiously optimistic region of parameter space. we assume m , which is not well constrained by the fit, is ≥ tev, and thus do not assume b will be observable. . χ production the process ub → dχ is the largest of the single production modes in the model, and under our assumption that m ≫ m , its rate is proportional to s r, thus providing a measure of the key mixing which is responsible for δgr. there is also a contribution from the left- handed mixing, but this is constrained to be small by precision data. we attempt to extract the signal (and thus measure sr) by looking at the semi-leptonic χ decay: pp → jχ → jbℓν where j is a light-quark initiated jet and ℓ = e or µ. to improve background rejection, we do not attept to reconstruct single χ production here, focusing on the dominant single χ signal. for our sample parameter point, the signal inclusive cross section, including branching ratios, is fb. the sm background (with very mild acceptance cuts on the jets) is . nb, dominantly wjj production, with smaller contributions from tt and single top production. events are showered and hadronized with pythia [ ], and we estimate detector effects with pgs [ ] using the default lhc detector model of madevent. to separate the signal from the background efficiently, we require that the event contain exactly one b-tagged jet with transverse momentum pt ≥ gev, one positively-charged lepton with pt ≥ gev (which is sufficient to trigger on the events even in high luminosity running), no more than two jets with pt ≥ gev, and missing momentum et ≥ gev. we further require that the invariant mass of the two highest pt jets mjj be ≥ gev. we assume the et arises from a neutrino present in a on-shell w decay, and use the w mass to reconstruct the longitudinal neutrino momentum. armed with that information, we can reconstruct the four-momentum for the w boson, which we combine with the b-tagged jet to form the invariant mass which in a signal event would reconstruct the χ mass of gev. we apply a wide cut to this quantity, requiring it to be in the range – gev. we found a signal acceptance of about % and a background suppression factor of . × − using these cuts. while the signal-to-background ratio remains small, sufficient statistics can be generated for a significant observation of the process and a measurement of the signal cross section. with fb− of data the total number of expected events – – j h e p ( ) exceeds the sm prediction by , equivalent to . σ, constituting a discovery of the single production process for χ, and with fb− the cross section can be measured to be ± fb, where systematic uncertainties in determining the acceptances are assumed to be small in comparison to the large statistical uncertainties. this measurement corresponds to , expected signal events over , expected background events. extracting sr from the cross section is straightforward, as all other quantities entering the conversion are known with effectively zero error compared to the measured cross section. we end up with a measurement of s r = . ± . . the discovery potential in this channel extends well beyond the mass studied here. azuelos et al [ ] found that a vector like t′ was discoverable through the t′ → wb channel up to mt′ ≃ . tev. our model predicts an identical signal, with comparable production cross section and more favorable branching ratio for this measurement. the fact that χ has charge − / is a very distinctive feature compared to other models of vector-like quarks, but difficult to establish experimentally. one could attempt to mea- sure the charge of the b quark produced in a χ decay; this has been successfully employed by tevatron experiments to establish the top quark charge [ , ], but depends sensitively on modeling the detector response correctly, and thus is beyond the scope of this work. additional strategies could be to examine processes such as χχγ, which is expected to lead to a successful lhc measurement of the top quark charge [ ]. we have performed simula- tions of χχγ production, but find that the contribution induced by photon radiation from the parent quark becomes lost in radiation from the w or lepton in its decay. the large χ mass has the unfortunate effect of both reducing the over-all rate substantially compared to the ttγ, and also collimates the χ decay products, making it more difficult to extract the cases where the photon is radiated by the final state lepton from that where it is radiated from the quark itself than was true for the well-spread out top quark decay products. ultimately, the most promising argument for the charge of the χ may be indirect by the failure to observe the decay mode χ → zt, which would generically be present for a charge / vector quark, which would be allowed to mix with the top. this argument rests on the assumption that one has observed b → zb, and thus knows that the newly discovered objects are in fact vector-like as opposed to chiral quarks. however, it is worth bearing in mind that even for a vector-like t′, the z-t′-t interaction is controlled by separate mixing angles from those in the b sector, and thus may turn out to be very small. . single b /b production after single χ production, the next largest single mirror quark production mode is single b production (including single b production), which proceeds through an fcnc z or h exchange in the t-channel. the rate for this process is proportional to s rc r, and thus provides another measurement of the mixing angle s r. we examine the feasibility of observing the process pp → jb → jbℓ+ℓ− through an intermediate z boson from the b decay (and also the conjugate process for b ). the signal cross section (including branching ratios) for mb = gev is . fb. the background is dominantly zbb and tt and is pb after acceptance cuts. in fact, the reasonable agreement between the experimental measurements of b → sγ and sm predictions requires that the product of the t-t′ and b-b′ mixings be . − [ ]. – – j h e p ( ) we require at least one of the leptons in the event to have pt ≥ gev, sufficient for triggering. we select events with at least one b-tagged jet with pt ≥ gev. the main criteria to distinguish between the signal and background are the reconstructed mass of two leptons, which should be close to the z mass and its combination with the b-jet to form an invariant mass close to m . in events with more than one b-tagged jet (as is often the case for the background processes), we combine the b-jet that has the largest pt with the lepton pair to form the reconstructed b mass. we require the reconstructed b mass to be within a gev window of the reference value of m = gev. this window contains . % of the signal rate after jet smearing. in addition, we place a restriction on the angular separation of ∆r ≤ between the pair of leptons, since the signal produces highly boosted z bosons from the b decay whose decay products are collimated. at an integrated luminosity of fb− the number of predicted signal events for our parameter point is , after applying the above mentioned cuts. the analysis efficiency is . %. the number of expected background events is after background suppression by a factor of . × − . the resulting significance is . σ, and the measurement of the mixing angle is s r = . ± . , which is comparable to the precision offered by single χ production. while not a direct reconstruction of the vector-like quarks, these two measurements together provide evidence that the primary mixing with the third generation sm quarks is through the bottom sector, with no apparent mixing involving the top (which is forbidden in our construction by u( )em but could be allowed in generic models of mirror quarks containing top-like objects). . electroweak b − χ production another process which allows us to extract information about the mixing angle is elec- troweak production of a pair of mirror quarks, χb through an s-channel w boson. the cross section, which is proportional to c r, turns out to be quite small due to the fact that on top of being governed by weak couplings, two heavy quarks are being produced. to analyze this signal we look at the process pp → χb → ℓ±ℓ∓bbℓ′ν (and its charge-conjugate version). this particular signature has the b decaying through a z into ℓ +ℓ− whereas χ decays as usual into wb. after acceptance cuts, the cross section for this signal is . fb. the background was generated using madevent and the relevant decays were obtained with bridge [ ] before showering and hadronizing with pythia. again detector ef- fects were estimated with pgs using the default lhc detector model of madevent. this resulted in a background cross section of . fb. due to the small number of events, distinguishing signal from background is difficult. in order to retain enough events to obtain sufficient statistics one must be conservative in applying cuts. we first require that the event contain two b-tagged jets with pt ≥ gev. since we expect the charged lepton pair decaying from the highly boosted z to be collimated we first find the ℓ±ℓ∓ pair with the smallest ∆r and combine it with one of the b jets to form an invariant mass (in a signal event this would reconstruct the b mass) which we require to be greater than gev. to determine which lepton is associated with the neutrino we again assume the et arises from a neutrino present in an on-shell w decay. we then find any charged leptons not – – j h e p ( ) belonging to the pair which decay from the z and out of those find the one with the smallest ∆φ relative to the missing et . we use the w mass to reconstruct the longitudinal neutrino momentum, and from that we reconstruct the four-momentum for the w boson and com- bine it with the other b-tagged jet with pt ≥ gev to obtain the invariant mass (in a sig- nal event this would reconstruct the χ mass) which we require to be greater than gev. with a signal acceptance of . % these selection criteria lead to an expected signal events at fb− . we expect background events after a suppression factor of . × − leading to a significance of σ for the signal over background. while this does not constitute a discovery, when combined with the information obtained from other signals, it provides evidence that the χ and b quarks form an su( ) doublet, and thus does help to verify the structure of the beautiful mirrors model. conclusions while the possibilities for discovery at the lhc are vast, it may be that there are clues as to what could be discovered in the form of modest deviations already present in lower energy data. in this article, we have discussed one such deviation, the forward-backward asymmetry of the bottom quark, which has persisted for more than a decade and appears to play a key role in the sm fit to the higgs mass. we have explored one particular model which addresses the discrepancy by adding additional vector-like quarks which mix with the b, subtly affecting its coupling to the z boson. these quarks are perfect targets for discovery at the lhc, which is likely to initially ob- serve them through pair production. we have examined the prospects for observing single production as well. while single production has smaller rates, being suppressed by elec- troweak strength couplings and mixing angles, it probes the basic phenomena responsible for the solution to the mystery of abf b. in particular, we have studied single χ produc- tion followed by the dominant decay χ → w +b, single b production followed by the decay b → zb → ℓ+ℓ−b, and pair production of χb (with the same decay chains as above). these processes are expected to be visible for quark masses up to about gev at a tev lhc with hundreds of fb− , and provide evidence that the χ and b quarks form a vector-like electroweak doublet which mixes primarily with the bottom quark. the primary mixing pa- rameter, s r, responsible for explaining the value of a b f b, can be measured at the % level. acknowledgments the authors are grateful for conversations with carlos e.m. wagner. t tait appreciates the slac theory group for their extraordinary generosity during his many visits. kk and r v-m would like to thank gabe shaughnessy, jamie gainer, and patrick fox for helpful discussions. research at argonne national 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( + . ) - . . originalan naučni rad mejkover televizija i mit o lepoti sažetak: pret po stav ka je da me di ji, za hva lju ju ći svo joj ulo zi ko mu ni ka to ra kul tur nih vred no sti i ide ja, uti ču i na de fi ni sa nje ide a la žen ske le po te. pr o ce si me dij ske re pre zen ta ci je ključ ni su u kon stru i sa nju kul tur nih „nor mi“ le po te žen skog te la, a ka po tro šnji ori jen ti sa no dru štvo u do stig nu ći ma estet ske hi rur gi je pre po zna je na či ne de mo kra ti za ci je i pri bli ža va nja ovom ide a lu. bu du ći me ša vi na ovih mo ti va, mej ko ver tv emi si je su pri mer me dij skog sa dr ža ja na osno vu či je ana li ze se po ku ša va ju ot kri ti zna če nja i me ha ni zmi po tvr đi va nja sa vre me nog mi ta o le po ti, ide je ko ju je pred lo ži la na o mi volf. ove emi si je mo gu se po sma tra ti i kao svo je vr sni me dij ski ri tual, ko ji ini ci ra u mit i le gi ti mi še nje go vu dru štve nu ulo gu. emi si ja “mo je no vo ja”, emi to va na na pr voj te le vi zi ji, pred met je krat ke ana li ze či ji ključ ni mo men ti ot kri va ju stal na me sta u me dij skoj re pre zen ta ci ji ak tu el nog mo de la žen ske le po te, po sle di ce ko je taj mo del pr o iz vo di i dru štve nih od no sa mo ći, na ko je odr ža va nje mi ta o le po ti uka zu je. ključnereči: mej ko ver tv, me dij ska re pre zen ta ci ja, mit o le po ti uvod sa vre me na kul tu ra i sva ko dne vi ca pr o že te su me dij ski po sre do- va nim sli ka ma, ko je nam se uti sku ju u svest kao vi zu el ni pe ča ti pret po sta vlje ne stvar no sti. uko li ko pri hva ti mo da me di ji ima ju va žnu ulo gu u prak si ozna ča va nja, to jest ne sa mo „sli ka nja“, već i do de lji va nja zna če nja, sta tu sa i po zi ci je fe no me ni ma ko ji nas okru žu ju, ja sno je da me dij ska pred sta va ni je sa mo upri zo re- nje, ni ti je ika da pu ki od raz stvar no po sto je ćeg. me di ji su va žan deo me ha ni zma kul tur nog sa mo o dr ža nja, oni su ži vi deo (sa mo) re pro duk ci je kul tu re, ko ji funk ci o ni še isto vre me no kao po lje i kao sred stvo pr o iz vod nje, ko mu ni ci ra nja i tu ma če nja kul tur nih vred no sti i ide ja. u tom smi slu je sa vre me na kul tu ra me dij ska, sneŽana milin perkoviĆ sneŽana milin perkoviĆ a pred sta ve ko je se pr o ce si ma re pre zen to va nja pre no se pu tem i je zi kom me di ja pred sta vlja ju od go va ra ju ća kul tur no pri pi sa na zna če nja i vi đe nja. pre ma stju ar tu ho lu (hall), pr o ces re pre- zen to va nja pod ra zu me va po ve zi va nje stva ri, poj mo va i zna ko- va u smi sle ne ce li ne i ujed no je pr o ces pr o iz vod nje i raz me ne zna če nja u kul tu ri. si stem re pre zen ta ci je ni je pr o sta ko lek ci- ja poj mo va, već se sa sto ji od raz li či tih na či na orga ni zo va nja, sku plja nja, ure đi va nja i kla si fi ka ci je poj mo va i us po sta vlja nja ve za me đu nji ma. u smi slu u ko jem ce lo kup na stvar nost pred- sta vlja mre žu zna če nja i kon stru ka ta , pr o ce si pred sta vlja nja su iz u zet no zna čaj ni za raz u me va nje kul tu re i ot kri va nje sup til nih i ne vi dlji vih ve za iz me đu raz li či tih dru štve nih či ni la ca. ana li- za me dij skih pred sta va vo di do po sto je ćih dru štve nih od no sa i uka zu je na po ve za nost mo ći da se uti če na pri pi si va nje zna- če nja sa mo ći ko ja se osva ja (i odr ža va) unu tar struk tu re da tih dru štve nih od no sa. te ma ovog ra da je me dij ska re pre zen ta ci ja žen skog te la pr o či ta- na pod sve tlo šću ide je mi ta o le po ti. mo gu će je iz dvo ji ti ne ko- li ko pret po stav ki na ko ji ma tekst po či va. pre sve ga, a u skla du sa pret hod no na pi sa nim, vla da ju će pred sta ve o že na ma pod uti- ca jem su me dij skog re pre zen to va nja. u svom ra du o re pre zen- ta ci ji že na u me di ji ma aj rin ko ster me jer i li zbet van zo nen na vo de tri di men zi je pred sta vlja nja – od nos pred sta vlja nja i re- flek si je stvar no sti, kul tur nih vred no sti i in ter pre ta ci je - i za klju- ču ju da su re al ne že ne mno go dru ga či je i ra zno vr sni je ne go što to me di ji pri ka zu ju. uz to, po što je žen sko te lo, za hva lju ju ći sve pri sut no sti re klam nih sli ka, po sta lo obje kat urba nog pej za- ža, že ne sa re kla me se re đe po ve zu ju s re al no šću, za raz li ku od „kre di bil nih“ mu ških mo de la, ko ji bi mo gli za i sta i bi ti ono što pred sta vlja ju. s dru ge stra ne, po što se že ne po sma tra ju sa mo kao mo de li, lut ke za pre svla če nje, nji ho vo če sto po lu na go te lo je re a li stič ni je od mu škog. pred sta vlja nje za vi si i od na či na či ta nja, gde se pri zo ri že na uglav nom po ve zu ju sa (he te ro)sek su al no šću, ’’pri ro dom’’ i tra di ci jom. autor ke ipak ka žu da že ne ni su sa mo pa siv ni po sma tra či, već su ak tiv ne u po sma tra nju dru gih že na i mu ška ra ca, kao i kon struk ci ji se be kao obje ka ta i su bje ka ta u ovim od no si ma gle da nja. naj zad, re pre zen to va nje se vr ši u skla- du sa va že ćim kul tur nim obra sci ma. li zbet van zo nen uka zu je na to da su fe mi ni stič ke stu di je po ka za le da po sto ji ve za iz me đu vi di npr. ber v., uvod u so ci jal ni kon struk ci o ni zam, zep ter bo ok world, beo grad . vi di mi li vo je vić s., Že ne i me di ji: stra te gi je is klju či va nja, u: Ča so pis za fe mi ni stič ku te o ri ju ge ne ro, po seb no iz da nje, pri re dio mi li vo je vić s., cen tar za žen ske stu di je, be o grad . me jer a. k. i van zo nen l., od brit ni spirs do era zma: že ne, mu škar ci i nji- ho vo pri ka zi va nje, u: stu di je kul tu re – zbor nik, pri re dio Đor đe vić j., slu žbe ni gla snik, be o grad , str. . sneŽana milin perkoviĆ me dij ske re pre zen ta ci je, re al no sti i dru štve nih prak si. kao što su me di ji uče stvo va li u stva ra nju ’’žen ske mi sti ke’’ še zde se tih go di na i for mu li sa nju ilu zi je o he te ro sek su al noj ro man si, i da nas su glav ni po sred ni ci he ge mo nij skih i ste re o tip nih vred no sti o že na ma i žen sko sti. mit o le po ti u knji zi ob ja vlje noj . go di ne (re i zda nje .), na o mi volf (wolf), upra vo go vo re ći o kli šeu da su že ne uvek pa ti le zbog le po te i za le po tu, uka zu je na pred sta vu ko ja di rekt no uti če na moć ko ju že na ima u okvi ru do mi nant no mu ške kul tu re. nje no mi šlje nje je da su že ne za ro blje ne u fik ci ju o le po ti, ko ja im se na me će upra vo u tre nut ku ka da sti ču od re đe nu dru štve nu moć. i u ra ni jim isto rij skim do bi ma su po sto ja li do mi nant ni estet ski ide a li (nji ho va pr o me nji vost i dru štve no-isto rij ska uslo vlje nost se ne po ri če), ali se sa da ideal le po te po sta vlja kao im pe ra tiv ko ji cr pe re sur se (vre me, sna gu, mo ti va ci ju) že na ko je ima ju šan su da se po sve te na pre do va nju na pr o fe si o nal nom pla nu. dru gim re či ma, u stra hu od na ru ša va nja i pre i spi ti va nja kul tur nog po- ret ka, ener gi ja že ne se pre u sme ra va ka ko bi ko ri sti la, a ne pod- ri va la si stem, te ona po red dve po sto je će (ku ća i po sao), bi va upo sle na i u tre ćoj sme ni (ulep ša va nje). slič no eko nom skoj is- pla ti vo sti „žen ske mi sti ke“, mit o le po ti pred sta vlja po gon sko go ri vo po tro šač kog dru štva. „Žen ska mi sti ka“, ko ja je u po sle- rat nim de ce ni ja ma že nu pre tvo ri la u ma đi o ni čar ku u svom do- me nu po kuć stva, tra ži la je od že ne da ku pu je za do ma ćin stvo; mit o le po ti zah te va kon stant nu po tro šnju u do me nu ulep ša va nja sop stve ne po ja ve. i kao što su se kuć ni apa ra ti „tr o ši li“ i me nja li no vim mo de li ma br že ne go što je to za i sta bi lo po treb no, bri ga o te lu po ja vi la se kao bezd no sa uvek no vim i oba ve zu ju ćim tren- do vi ma. tre ba is ta ći da mit ne ra ču na (sa mo) na ta šti nu, ma da po tro šač ki duh sva ka ko isi ja va njo me, već na od go vor nost da se že na po bri ne za svo je po lje de la nja i na svest (kon stru i sa nu) o to me da le po ta funk ci o ni še kao va lu ta, ko ja ima svo ju vred- nost i fluk tu a ci je. po red to ga što se sma tra ula zni com za uspeh, le po ta po sta je cilj po se bi (po put nov ca) i nu di pla ce bo ose ćaj mo ći. kva li fi ka ci ja pr o fe si o nal ne le po ti ce (eng. pr o fes si o nal be a uty qu a li fi ca ti on) u stva ri iz jed na ča va le po tu sa uspe hom. po red to ga što emo tiv no uni šta va, isi sa va ener gi ju, ane ste zi ra i za ra đu je na ra čun sa mo po u zda nja že na, mit o le po ti izo lu je že ne u pri vid noj so li dar no sti, ko ja je po vre đu ju ća, tr ži šna i stvo re na u mu škoj kul tu ri. u ča so pi si ma, ka že volf, „ono što su ured ni ci u oba ve zi da ka žu da mu škar ci že le od že na je ste za pra vo ono što zar ima ne čeg sli ko vi ti jeg od za jed nič kog šo pin ga, raz me nji va nja no vih di- je ta (i re ce pa ta) ili da na u sa lo nu le po te pr o ve de nog sa dru ga ri ca ma, ko ji ma za vi di mo jer su lep še, mr ša vi je ili vo lje ni je od nas. sneŽana milin perkoviĆ ogla ši va či že le od že na“ . re klam na in du stri ja je glav ni cen zor ide a la le po te. poput no ve re li gi je, mit o le po ti ka že da je žen sko te lo - za raz li ku od ori gi nal nog mu škog - ne sa vr še no i ne do vr še- no, pa se kul tu ra spa si telj ski do mi šlja u na či ni ma da ga po pra vi i spa se. u ta kvom kon tek stu, bu du ći da je du (greh su vi šnih ka- lo ri ja) i ži ve u vre me nu (greh sta re nja), že ne su uvek u ne kom smi slu gre šne. volf za pa ža da, ako bi smo su di li pre ma ča so pi si- ma, ne bi smo zna li ka ko iz gle da že na od pe de set go di na. mit da mu škar ci sta re „bo lje“ od že na u stva ri skri va da je mu škar ci ma do zvo lje no da sta re do sto jan stve no i da ej dži zam ima uoč lji ve ni jan se ka da je reč o od no su po lo va. uz opa sku da že ne umi- ru dva pu ta – kao le po ti ce i stvar no – volf do da je da je „va žno ka ko že na iz gle da za to što ni je va žno šta go vo ri“ . za ro blje na u ne sa vr še nom te lu, že na se okre će in du stri ji ulep ša va nja, ko ja se da nas od re kla la žnih pr o ro čan sta va o več nom spa se nju i ume sto to ga nu di „za šti tu od stre sa i spo lja šnjih uti ca ja“. sprem na je da pla ti naj sku plji tret man, da bar mo že da umi ri svo ju sa vest da je po ku ša la, ka kav god is hod za i sta bio. u pred go vo ru no vom iz da nju svo je knji ge, volf pri me ću je da se u me đu vre me nu mit pr o me nio i de mo kra ti zo vao. da nas i mu škar ci mo gu da „uči ne ne što za se be“, a kli jen te la in du stri- je le po te po sta je sve mla đa, na kri li ma tvrd nje da ni ka da ni je ra no po če ti sa tret ma ni ma, u toj me ri da i estet ska hi rur gi ja pre- la zi u sfe ru pre ven ti ve. usme ren na pr o pi si va nje po na ša nja, a ne iz gle da, mit o le po ti ne pod ra zu me va ja snu de fi ni ci ju le po- te. on je plu ra li zo van i ti me obez be đu je bes ko na čan pr o stor za kon stant nu na do grad nju. da bi obez be di la pri vid iz bo ra, le po ta mo ra bi ti ra zno vr sna. da bi bi la ide al na, mo ra bi ti ne do sti žna. da bi bi la tr ži šno kon ku rent na, mo ra se isto vre me no či ni ti da je na do hvat ru ke. Že ne i hi rur gi ja – ru žni pa či ći i ane ste zi ra ne le po ti ce po jam estet ska hi rur gi ja, ko ji će se ko ri sti ti u tek stu, ozna ča- va prak su hi rur ških in ter ven ci ja ko ja te ži od re đe nom estet skom is ho du i po tvr đu je od re đe ni estet ski ideal. bu du ći da je reč o te mat skom iseč ku, tekst je ne mi nov no ogra ni čen i ne mo že se ba vi ti mno gim za ni mlji vim te ma ma. naj pre, ne će se pre i spi ti- va ti ma glo vi te gra ni ce iz me đu ova ko shva će ne estet ske i re kon- struk tiv ne hi rur gi je, ko ja po de fi ni ci ji sa ni ra ošte će nja na sta la po vre dom ili „is pra vlja“ uro đe ne fi zič ke de for mi te te, od no sno funk ci o nal ne ne do stat ke (o či joj se kon stru i sa no sti ta ko đe mo že ras pra vlja ti). da lje, ana li zi ra se pre sve ga estet ska hi rur gi ja u wolf n., the be a uty myth, har per col lins, new york , str. . ibid., str. . sneŽana milin perkoviĆ slu žbi mi ta o le po ti, ma da se ne pre vi đa po sto ja nje mo guć no- sti dru ga či jih tu ma če nja, ali i prak tič nih pri me ra i pri me na iste. ta ko đe, reč je o le po ti žen skog te la, pa ana li za ob u hva ta sa mo ovu po pu la ci ju, ne za la ze ći u to da mit evi dent no ko lo ni zu je i do me ne mu ške te le sno sti, kao i to da se o hi rur gi ji mo že go vo ri ti i kao o mo guć no sti pre va zi la že nja i/ili (re)kon struk ci je fi zič kih, te le snih da to sti, uklju ču ju ći po la. de ba te, ko je se u fe mi ni stič koj li te ra tu ri vo de u ve zi sa estet- skom hi rur gi jom, uglav nom se kre ću iz me đu sta no vi šta da hi- rur gi ja mo že ima ti oslo ba đa ju ći po ten ci jal i onog da hi rur gi ja do dat no ste že obruč oko žen skog te la na me ta njem (ne)do sti žnog ide a la. ke ti dej vis (da vis) vi di estet sku hi rur gi ju i kao pr o blem i kao re še nje: ona isto vre me no od u zi ma i da je moć že na ma. kul- tu ra for si ra od re đe nu sli ku o žen skom te lu, ali ne tre ba za ne- ma ri ti in di vi du al na žen ska is ku stva i kon tek ste. Že ne ni su „kul- tur ne lu de“ i de la ju kao su bjek ti ka da su sve sne svo jih iz bo ra i po nu đe nih op ci ja. su zan bor do (bor do), me đu tim, kri ti ku je stav da se u ve zi sa hi rur gi jom uvek go vo ri o iz bo ru i slo bo di da se po sop stve noj že lji bi ra te lo. ako že na de la pod uti ca jem me- dij skih sli ka, ne mo že se go vo ri ti o pra vom de la nju. ope ra ci ja je, ka že bor do, vi še od in di vi du al nog iz bo ra – to je na ra sta ju ća in du stri ja i nor ma tiv na kul tur na prak sa, ali i uzrok pat nje že na jer se stal no po di že le stvi ca u to me šta se sma tra pri hva tlji vim li cem i te lom. kul tu ra ka pi ta li zma i pr o fi ta nas osna žu je je di- no u prav cu ono ga što bi smo mo gli da bu de mo, ali ne i onim što je smo. pr o blem ni je u to me šta se sma tra le pim, već šta se pr o gla ša va nor mal nim. upra vo su pr o ce si nor ma li za ci je i ho mo ge ni za ci je glav ni pr o- blem u ve zi sa estet skom hi rur gi jom. u od bra ni prak se, na pa da- ne da je pre va rant ska (ope ri še na zdra vim te li ma), tri vi jal na i ne- po treb na, hi rur zi is ti ču neo p hod nost svo je de lat no sti u kul tu ri u ko joj je fi zič ka po ja va va žna za in di vi du al nu sre ću i bla go sta nje. hi rur gi ja je sa mo re še nje već po sto je ćeg pr o ble ma, ne u tral na teh no lo gi ja sta vlje na na ras po la ga nje kul tu ri, u či jim de fi ni ci ja- ma tre ba tra ži ti kriv ca za po sto je će „nor me“. bra ni o ci ove teh- no lo gi je do da ju da se gra ni ca iz me đu nor mal nog i ab nor mal nog sva ko dnev no po me ra, pa hi rur gi ja po sta je sred stvo za pr o me nu te la pre ma lič nim pre fe ren ci ja ma, otva ra ju ći do sa da ne po sto je- će mo guć no sti sa mo de fi ni sa nja i eman ci pa ci je od oko va fi zič- ke da to sti. u stvar no sti, iako se okru že nje za kri ti ku pr o me ni lo, tren do vi u hi rur gi ji uka zu ju na po sto je će i mo gu će pr o ble me ko ji re vi di ra ju ovo sta no vi šte o ne u tral no sti. hejz (heyes) i džo uns (jo nes) pi ta ju da li je ope ra ci ja iz bor ako je taj iz bor pred o dre đen ši rom pa tri jar hal nom struk tu rom, ko ja hi rur gi ju po sta vlja kao je di nu op ci ju u sve tu ne pri ja telj ski na stro je nom pre ma ženskim sneŽana milin perkoviĆ te li ma. hi rur gi ja mo žda po zi va na sa mo di jagno zu, ali ne nu di psi ho lo ške kon sul ta ci je. hi rur zi svo ju oblast, ka že ke trin mor- gan (mor gan), vi de u bi o teh no lo gi ji „po bolj ša nja“ ljud skih bi ća. sva ko ko se ose ća lo še u svom te lu je kan di dat za ope ra ci ju, ali kul tu ra na me će od go vor nost zbog ko je zvu či su lu do od bi ti šan- su da se (p)osta ne lep. s ob zi rom na sve ve ći br oj mu ška ra ca ko- ji se pod vr ga va ju hi rur škim in ter ven ci ja ma, bu duć nost hi rur gi je će bi ti vi še od re đe na et nič kom pri pad no šću ne go po lom. ovu či nje ni cu mor gan vi di kao pa ra doks oslo ba đa nja od „da tog te la“ u „kul tur no za mi šljen ideal“: bri sa nje pre po zna tlji vih et nič kih raz li ka još je je dan ob lik ho mo ge ni za ci je na ko ju uka zu je sta ti- sti ka estet ske hi rur gi je. pi ta nje je, ipak, da li že li mo da ži vi mo u sve tu ko ji ra di je za ma ski ra raz li ku (i de mo kra ti zu je taj pr o ces) ne go što se su o ča va sa njom, u sve tu ko ji kao re še nje za raz li ku vi di nje no po ti ra nje. mej ko ver te le vi zi ja re la tiv no nov, mej ko ver tv (ma ke o ver te le vi sion) je te le vi zij- ski for mat ko ji kom bi nu je re a lity for mu i opro ba ni dra ma tur ški „pre i po sle“ re cept, u ko jem se pri ka zu je tran sfor ma ci ja oso be ili objek ta , uglav nom pra će na ljud skom pri čom ko ja omo gu ća- va iden ti fi ka ci ju i/ili sa u če šće u pr o ce su. baj ko vi ta tran sfor ma- ci ja žen skog te la (ma kar sa mo sti li zo va nje) kao ide ja je mo žda sta ra ko li ko i baj ka o pe pe lju gi, ali se de si lo da te le vi zij ski ži vot poč ne u tre nut ku ka da estet ske in ter ven ci je i ko zme tič ka in du- stri ja po sta ju po zna te i go to vo (ali ni ka ko pot pu no) do stup ne ve ći ni sta nov ni štva. pr va za pa že ni ja emi si ja ko ja je kom bi no- va la estet sku hi rur gi ju i ovaj te le vi zij ski for mat bio je eks trem ni pre o bra žaj (ex tre me ma ke o ver), ko ji se u ame ri ci emi to vao od . do . go di ne. za ni mlji vo je da su, iako je u na slo vu imao reč „eks trem ni“, uče sni ce uglav nom „pre o bra ža va ne“ u ne što što bi se mo glo na zva ti „pri rod nim iz gle dom“. po tre ba da se bu de lep na od re đen na čin, a da se isto vre me no za dr ži pri vid „pri rod no sti“ je in di ka tiv na – ova pred sta va omo gu ća va kon sti- tu i sa nje od re đe nog ide a la le po te ko ji bi mo gao da po sto ji u pri- ro di i či ja se la žnost mo že la ko sa kri ti (slič no „pri rod noj“ ni jan si far ba ne ko se ili sup til no sti „pri rod ne“ šmin ke). za ne ke že ne to je bio ko rak una pred ka že lje nom iz gle du, dok je za dru ge bio ko rak una zad, ka „iz gu blje noj“ mla do sti. bi lo da se pe gla- ju stvar nost ili go di ne, pri me ću je se ve za po jav no sti i uspe ha. su zan frej zer (fra ser) uoča va da že ne mo ti vi sa ne za pr o me nu heyes c. j. and jo nes m., co sme tic sur gery in the age of gen der, in: co- sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as hga te pu- blis hing ltd, far nham , str. . mi sli se na emi si je u ko ji ma se re no vi ra ju ku će, po slov ni objek ti, pre vo zna sred stva itd. sneŽana milin perkoviĆ to vi de kao pr o je kat, do bro ula ga nje ili na čin da se ose ća ju bo- lje u sop stve nom te lu. kao pra vo če do svog do ba, „mej ko ver kul tu ra“ orga ni zo va na je i oko vred no sti stal nog una pre đe nja i tvo re je je zik ra da i je zik ri tu a la. u mej ko ver emi si ja ma pod ra- zu me va se na gla ša va nje auto no mi je i sa mo za do volj stva, lič ne od lu ke i mo ti va ci je za uče šće, ali i is ti ca nje pat nje i te škog ra da ko ji pret ho di ovoj od lu ci. na taj na čin, re la tiv no br zo po stig- nu ta le po ta (ali ne i sa svim bez bol na) do bi ja svo je oprav da nje ne sa mo u pat nji pre tr plje noj zbog ne za do volj stva sop stve nim iz gle dom, već i u re še no sti, hra bro sti da se sop stve na sud bi na „uzme u svo je ru ke“. kao ve ćin ske pr o ta go nist ki nje ovih re a lity emi si ja pri ka zu ju se že ne ko je pr o la ze niz estet skih (hi rur ških i stil skih) tret ma na sa ci ljem pre o bra ža ja u „lep še te lo“. u svo joj ra zno vr sno sti, mej ko ver tv ob u hva ta i emi si je ko je pri ka zu ju „sit ne“ ko rek ci je (u sti lu obla če nja, ulep ša va nja), ali i one ko je pri ka zu ju ozbilj ni je hi rur ške in ter ven ci je, od ko jih je jed na pred- met ana li ze ovog ra da. mej ko ver emi si je su pri mer me dij skog po sre do va nja u pre no še nju va že ćih nor mi žen ske le po te, ali se de li ći sla ga li ce na la ze u ve ći ni po pu lar nih for mi, gde me di ji vr še funk ci ju pred sta vlja ča ido la i ba ze obo ža va nja, ali i za ve re ni ka ko ji po ka zu je „obič nim že na ma“ do stup ne na či ne da se ideal (idol) opo na ša i ote lo vi. mo je no vo ja – „ne ke že ne ostva ri će baj ku“ ili „ne ma le po te bez bo la“ ne ke že ne ostva ri će baj ku tran sfor ma ci jom fi zič kog iz gle da povratiće sa mo po u zda nje. mo je no vo ja mo je no vo ja na ja vlju je pri če o že na ma ko je su “do bi le je din- stve nu pri li ku da pr o me ne svoj fi zič ki iz gled ka ko bi po vra ti- le smi sao ži vo ta i pre va zi šle sve pr o ble me ko je su zbog to ga ima le” . uče sni ce uglav nom do la ze iz ma te ri jal no i so ci jal no ugro že nih po ro di ca, ve ći na su sa mo hra ne maj ke, ne ko li ko njih je pre tr pe lo fi zič ko i psi hič ko na si lje, a ne za do volj stvo zbog emi si ja mo je no vo ja emi to va na je na pr voj te le vi zi ji od ok to bra . do ja- nu a ra . srp ska je ver zi ja emi si je eks trem ni pre o bra žaj. u dva na est epi- zo da dva na est uče sni ca je pr o šlo kr oz niz ulep ša va ju ćih tret ma na, u ko ji ma su do mi nant nu ulo gu ima le estet ska i re kon struk tiv na hi rur gi ja, sto ma to log, psi ho log i gru pa sti li sta i šmin ke ra, sa ci ljem da „vra te le po tu“ že na ma ko je su, naj če šće usled te škog ži vo ta, za ne ma ri le sop stve ni iz gled. u ana li zi emi- si je kao me dij skog sa dr ža ja, iz ja ve uče sni ca po sma tra ju se kao is po ve sti, bez ob zi ra na to da li su ne ki ele men ti re zul tat sce na ri stič ke in ter ven ci je. ana li za ob u hva ta mej ko ver emi si ju u ce lo sti - pri ka za ni sa dr žaj, nje go va mo gu ća tu- ma če nja i ko men ta re gle da la ca. svi ci ta ti i ko men ta ri gle da la ca pre u ze ti su sa saj ta pr ve te le vi zi je. u arhi vi se na la ze snim ci svih emi to va nih emi si ja. u to ku je pri ja va za in te re so va nih za dru gu se zo nu. vi di: http://www.prva.rs/sr/ video/zabava/moje-novo-ja.html sneŽana milin perkoviĆ “zapu šte nog fi zič kog iz gle da” na te ra lo ih je da po tra že na čin da se pr o me ne i da o ono me što ih mu či “jav no i otvo re no pr o go- vo re”. sko ro sva ka že na se ža li da iz gle da sta ri je ne go što bi tre- ba lo i da se od lu či la na pr o me nu zbog se be i svo je oko li ne, ko ja de li njen stid i pri me ću je nje no “pr o pa da nje”. ka me re pra te ce lo vit pr o ces nji ho vog pre o bra ža ja. u uvo du se upo zna je mo sa uče sni ca ma i nji ho vim po ro di ca ma. snim ke evi- den ti ra nih ne do sta ta ka pra ti nji ho va is po vest. ne pre te ra no sup- til nim dra ma ti za ci ja ma pri ka zu je nam se ono što su do ži ve le i do ži vlja va ju (uklju ču ju ći na si lje, gde upra vo uče sni ca “glu mi” sce ne na pa stvo va nja, kri ju ći li ce ru ka ma). Že ne se sni ma ju ka ko sto je pred ogle da lom, tu žnih gri ma sa, po sma tra ju svo je li ce i ob- na že ne gru di (ovim se ta ko đe ne sup til no na ja vlju ju in ter ven ci je ko ji ma će se pod vrg nu ti). go vo re da se zbog svog iz gle da sti de, “za tva ra ju se u ku ću”, de pre siv ne su i ne vi de iz laz iz po sto je ćih pri li ka. fi zič ki pre o bra žaj bi im po mo gao da po vra te sa mo po u- zda nje. a. r. ( ) iz ja vlju je da je de cu sra mo ta da im ona ide na ro di telj ski sa sta nak. b. t. ( ) ka že da se sti di zbog svo je de ce: “ja znam da oni me ne vo le, ja sam nji ho va ma ma, ali ka kva sam ja ma ma ka da iz gle dam ka ko iz gle dam.” na ra tor ob ja šnja va da i ne žna unu tra šnjost ovih že na pr o pa da zbog to ga što se ne mo- že na vik nu ti na gru bu spo lja šnost. sve uče sni ce ve ru ju da će s lep šim iz gle dom lak še na ći po sao ili bo lje ra di ti onaj ko ji ima ju. “ne ose ćam se la god no ka da ne ko mo že da pr o či ta sa mog li ca taj ne ki ži vot ko ji imam”, iz ja vlju je jed na uče sni ca. j. v. ( ) je sa mo hra na maj ka ko ja ži vi s ro di te lji ma. ka že da bol ope ra ci je ni je ni šta na spram bo la ko ji tr pi u stvar nom ži vo tu zbog to ga što je ru žna. re ši la je da ži vi svo je go di ne. po za vr šet ku pre o bra ža ja iz ja vlju je: “to ni sam ja i to mi se mno go svi đa!” ov de je reč o stvar nim že na ma ko je no se stvar ne tra u me. ali, tra go vi pret hod nog ži vo ta, kao zlo či na ko ji je osta vio svo je ru- žne tra go ve, mo ra ju se iz bri sa ti da bi se pre šlo u bo lju su tra šnji- cu. za to što su te ško ži ve le, one su za ne ma ri le svoj iz gled, ali za to što su za ne ma ri le iz gled one ima ju tra u me i zdrav stve ne pr o ble me. i sto ga, ako pr o me ne iz gled, one mo gu da se oslo- bo de svo jih tra u ma i poč nu is po čet ka. na rav no da se ne oče- ku je da će nji ho vi pr o ble mi ne sta ti, ali u sve tu u ko jem si ro- ma štvo i ne do sta tak le po te iza zi va ju stid va žno je da se iz bri šu tra go vi, da se ne gi ra zlo čin, da se iz gle da kao da pr o ble mi ne po sto je. kan di dat ki nje su upra vo oda bra ne zbog svo jih te ških frej zer u svo joj ana li zi ka že da je ak ce nat mej ko ver te le vi zi je na lič nom raz- vo ju i in tim nim ve za ma kao mo ti va ci ji za ope ra ci ju, či me se re pro du ku je žen skost na re la tiv no tra di ci o na lan na čin. fra ser s., agency ma de over? co- sme tic sur gery and fe mi ni nity in wo men`s ma ga zi nes and ma ke o ver te le- vi sion, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as hga te pu blis hing ltd, far nham , str. . sneŽana milin perkoviĆ pri ča, ko je delu ju kao iz go vor i kao kri te ri jum kva li fi ka ci je za tran sfor ma ci ju. nji ho va baj ka mo že da poč ne tek ka da do ka- žu da za slu žu ju da im se ona de si. mit o le po ti zah te va da se le po ta vi di kao re zul tat tru da, pre tr plje nog bo la, ali i oba ve za že ne. ona je ta ko đe kar ta u jed nom prav cu za od la zak iz sve ta si ro ma šnih i ru žnih. Čo vek s mar ke rom i “nor mal ne“ kon tu re žen skog te la pre o bra žaj po či nje upo zna va njem sa ti mom le ka ra ko ji će “iz- bri sa ti iz gu blje ne go di ne” i iz ve sti “ma gi ju” tran sfor ma ci je, na- kon če ga će uče sni ce “ugle da ti svoj iz me nje ni lik u ogle da lu i upo zna ti svo je no vo ja”. pr vo se upo zna ju sa sto ma to lo gom, ko ji će im bu kval no po da ri ti osmeh , a za tim i hi rur zi ma, sa ko ji ma se do go va ra ju o že lje nim in ter ven ci ja ma. oni su em pa- tič ni sve šte ni ci ove ob uj mu ju će re li gi je le po te ko ji će pr o ve sti is ku še ni ce ka lep šoj bu duć no sti i ini ci ra ti ih u no vo te lo. se be na zi va ju vi zi o na ri ma, ko ji svu da vi de mo guć nost po prav ke: iz- bo ra no li ce, zu bi, no se vi, ja go di ce, obr ve, kap ci se se ku, pri te žu, kle šu, is pra vlja ju, vi šak ma sno će na te lu se usi sa va i pre me šta on de gde ne do sta je, ukla nja ju se ožilj ci i dru ge „ne pra vil no sti“ i asi me tri je te la; zad nji ce su za teg nu te, gru di oba ve zno po dig- nu te i sko ro uvek ve će, tvr đe i ne po mič ni je ne go ra ni je. bo toks, hi ja lu ron ska ki se li na, si li kon, li po suk ci jom iz va đe na sop stve na ma sno ća, bi ser ne na vla ke i is te sa ni no se vi i bo ko vi ma te ri jal su ovih sa vre me nih va ja ra. fri ze ri i šmin ke ri oba vlja ju fi nal ne ra- do ve iz vla če ći ne ke po ten ci ja le, kon tra ste, si me tri ju i is ti ču ći fi- gu ru, kon tu ru i ne iz be žni per so na li ti. Že na ni je go tov pr o iz vod, već ne što od če ga se že na mo že na pra vi ti. po če tak pr o me ne je sva ka ko na crt. Čo vek sa mar ke rom ozna ča- va me sta gde tre ba in ter ve ni sa ti. Že ne sa ra đu ju u vi zi o nar skom ra du, go vo re ći o svo jim ne si gur no sti ma i ma na ma. nji ho va go- to vo na ga te la ni su sek su a li zo va na, jer u ovom tre nut ku one se ne pred sta vlja ju kao obje kat že lje (na pro tiv, one ni ne mo gu bi ti pred met že lje, ovi ka dro vi to že le da do ka žu). na kon upo zna va- nja sa pa ci jent ki njom, tim le ka ra se još jed nom kon sul tu je i od- re đu je re do sled in ter ven ci ja. za to vre me, ne ko od čla no va po- ro di ce po ma že uče sni ci da se „opro sti od svog do sa da šnjeg iz- gle da“. na kon ni za ope ra ci ja, su sre ta sa psi ho lo ški njom (ko ji se pri ka zu je po sle od la ska u šo ping) i neo p hod nih kon tro la, no vo te lo uče sni ce se pod vr ga va fi nim in ter ven ci ja ma fri ze ra, šmin ke- ra i sti li sta, te ove ko ve ču je pri stoj no sek se pil nim fotogra fi ja ma. ne do sta tak ili loš kva li tet zu ba je u toj me ri pri su tan kod uče sni ca da su ne ki gle da o ci ko men ta ri sa li da je ve ća sra mo ta lo ša hi gi je na i ne mar pri ja vlje nih ne go nji hov fi zič ki iz gled. pri me ti li su i da bi emi si ja tre ba lo da se zo ve mo ji no vi zu bi, te da ve ći ni uče sni ca za pra vo ni šta dru go i ni je ne do sta ja lo. sneŽana milin perkoviĆ pre ne go što će se vra ti ti svo joj po ro di ci i pr vi put po ka za ti pred nji ma (i te le vi zij skim gle da li štem) re zul tat pr o me ne, že na sta je pred ogle da lo pr o me nje na, ovaj put za i sta za do volj na i sreć na. baj ko vi ta tran sfor ma ci ja i tri jumf le po te kru ni še se fi nal nim na- stu pom na cr ve nom te pi hu pred po ro di com ko ja je želj no iš če- ku je. emi si ja nam, kao re klam no-obra zov ni sa dr žaj, nu di i ob ja šnje- nje po stup ka i sred sta va ko ji se ko ri ste u ovom estet skom (re) mo de li ra nju. ta ko sa zna je mo šta tre ba i šta i ka ko mo že da se pr o me ni. cilj in ter ven ci ja je „pri rod ni iz gled“. je dan od hi rur- ga iz go va ra da sko ro sva ka že na ima na bo ko vi ma ma sno tki vo, po či jem ukla nja nju se do bi ja „pra vil na obli na žen skih ku ko va“ u pri ro di, da kle, ne po sto ji „nor mal na“ (le pa) kon tu ra žen skog te la. Že ne ni su „pri rod no“ le pe, već su ma te ri jal iz ko jeg se mo- že is kle sa ti le po ti ca. pr o to kom vre me na, po treb no je odr ža va- ti do stig nu tu „pra vil nost“. po tro šnja je de mo krat ska te ko vi na, pa je sva ka že na po ten ci jal na kan di dat ki nja; ona je ta ko đe zver u bezd nu i tra ži stal nu po tro šnju ka ko bi se po tvr di la. ide a lan iz gled ima že na ko ja ni je ra đa la, pa se bri šu tra go vi ra đa nja; že na ko ja ni je osta ri la, pa se bri šu tra go vi go di na; že na ko ja je „nor mal na“, pa se bri šu tra go vi ge ne ti ke. ono što se ozna ča- va kao ne le po (ru žno) iz jed na ča va se sa bo le snim, a bo le sno se mo ra le či ti. le po ta ide pod ru ku sa zdra vljem, ko je se po i sto- ve ću je sa mla do šću. mla dost je zlat no do ba in du stri je le po te, ali je to če sto ne po sto je ća mla dost (za pra vo ne sop stve na, već mla dost uop šte), bu du ći da je upra vo to pe riod ka da se raz vi ja- ju kom plek si zbog ve li kih no se va i ma lih gru di. da bi iz gle da le „nor mal no“, gru di mo ra ju bi ti ve će, u skla du sa gra đom, a nos ma nji, u skla du sa li cem. na tr o nu estet ske hi rur gi je sva ka ko su si li kon ski im plan ti i, ka ko je na o mi volf na zi va, zva nič na doj ka. ope ra ci ja gru di je go to vo kul tur na nor ma na ko ju že ne pri sta ju, a ko ja pot pu no me nja bi o lo šku funk ci ju orga na. funk- ci ja ko ju ima ju u re pro duk ci ji i maj čin stvu sim bo lič no se od u zi- ma, jer se gru di opu šte ne usled do je nja pr o gla ša va ju bo le snim. je di na funk ci ja ko ju žen ske gru di tre ba da ima ju je ste estet ska, a je di ni ob lik je onaj ko ji pr ko si svim pri rod nim za ko ni ma, uklju ču ju ći gra vi ta ci ju. aso ci ja ci je na ri tual su br oj ne: že ne će pr o ve sti tri me se ca van svo jih ku ća u svo je vr snom va ku u mu iz me đu ru žne pr o šlo sti i lep še bu duć no sti (re či ko je u ne ko li ko na vra ta ko ri sti i na ra tor). ulep ša va nje, po seb no ono ve za no za spe ci jal ne pri li ke, če sto je ste ri tu al na prak sa. u ovom slu ča ju ono pod ra zu me va pre laz iz jed nog sta nja u dru go, iz me đu dva te la, dva ži vo ta. po sto ji na rav no sa zna je mo i ko to mo že da ura di, bu du ći da se upo zna je mo sa pr o fe- si o nal nom bi o gra fi jom le ka ra i us pe si ma nji ho ve kli ni ke. sneŽana milin perkoviĆ po sve će ni va ku um pr o stor, u ko ji uče sni ce bi va ju is pra će ne od stra ne ne kog od bli skih ro đa ka ili pri ja te lja, a ko ji ma u taj pr o- stor ni je do zvo ljen pri stup. bu du će le po ti ce se uspa vlju ju, dok glav ni po sao oba vlja ju oni po sve će ni u ri tu al noj prak si. te lo se pr o pu šta kr oz niz in ter ven ci ja sa vre me ne ma gi je ulep ša va nja i bu di u no vom ob li ku. ka da se vra ti svo joj sva ko dne vi ci, vre me po no vo po či nje da te če. ka ko ova sko ro ri tu al na for ma ob na vlja mit o le po ti? ona pre sve ga po tvr đu je le po tu kao va lu tu. sva ka že na je od go vor na i po zva na da pri ne se žr tvu bo žan stvu le po te. je di ni iz go vor je stvar ni ži vot ko ji uzi ma svoj da nak tr o še ći te lo i cr pe ći le po tu iz nje ga. estet ska hi rur gi ja se po ja vlju je kao lek za ovu bo lest, mo guć nost bri sa nja do ka za o zlo či nu ko je je te lo (i duh sa njim) pre tr pe lo. za ni mlji vo je da na ne ki na čin emi si je ovog ti pa raz- ot kri va ju no vu žen sku mi sti ku, jer se le po ta nji ho vog te la vi še ne po sma tra kao mi ste ri ja u ko ju su sa mo one upu će ne. Či ni se da je uče sni ca ma emi si je le po ta ve o ma va žna i da su iskre no sreć ne zbog svo je pr o me ne. za ni mlji vo je, me đu tim, uve sti u ana li zu mi šlje nja gle da telj ki i gle da la ca, ko ji, na pri- mer, pri me ću ju da u emi si ju ni su do vo đe ne de be lju ška ste že ne, već one ko ji ma je sa bo ko va ski nu to tek to li ko ma sti ko li ko je bi lo po treb no da se is pe gla ju iz bo ra na li ca. ne ko li ko mu ška ra ca sma tra da je po sre di dis kri mi na ci ja, jer su se pri ja vi li, ali ih ni ko ni je zvao, pa za klju ču ju da je emi si ja na me nje na is klju či vo že- na ma. jed ni vi de emi si ju kao pri li ku da se po tre sna ži vot na pri ča tram pi za sku pu estet sku ko rek ci ju, dru gi da je to hu man po tez i da uče sni ce za slu žu ju do slov no lep ši ži vot, tre ći da po sto je oni ko ji ma je ope ra ci ja neo p hod ni ja i da u emi si ji ima pre vi še pa te- ti ke. jed noj gle da telj ki sme ta „pr o mo ci ja mu če ni štva“ u emi si ji, kao da sva ka že na tek žr tvo va njem do ka zu je da je pra va maj ka i že na. dru goj sme ta po ru ka emi si je da sve že ne ko je ni su le pe tre ba da se sti de. “ne po sto je ru žne že ne, već sa mo one ko je ne ma ju no vac”, ka že ona. ve ći ni sme ta ob na že nost že na, ma da jed na gle da telj ka kri ti ku je ta kav stav re či ma: “ima li išta ero- tič no u tom una ka že nom i iz mu če nom te lu? i šta je tu sra mo ta? nje no te lo je sli ka na šeg dru štva. sa mo što ne po sto ji hi rurg ko ji nas, kao dru štvo i na rod, mo že da ulep ša.” re kla me za ko zme tič ke pr o iz vo de stal no po sta vlja ju pi ta nje da li je le po ti ca ro đe na ta kva ili kri je ne ku taj nu. u sce na ma mej ko ver te le vi zi je ob ja šnja va se sva ki ko rak u pr o ce su ko jim sva ku že nu mo že mo uči ni ti ona ko le pom ka- ko u tom tre nut ku zah te va tre nut na „nor ma“. sneŽana milin perkoviĆ za klju čak ob no va mi ta o le po ti ili si zi fov po sao „ka da od raz u ogle da lu pr o u zro ku je stid, bez volj nost i du bo ku tu gu, sprem ni smo da ura di mo sve ka ko bi smo se bi i dru gi ma bi li lep ši. ka ko iz gle da pr o bu di ti se jed nog ju tra i po no sno re ći: ovo je ste mo je no vo ja.“ mo je no vo ja u te žnji da za ne ma re (ili po me re u dru gi plan) stvar ne pr o ble me i da hi rur škim no žem ise ku do ka ze o ži vot nom is ku stvu, emi si je ko je pr o mo vi šu estet sku hi rur gi ju mo gu iza zva ti am bi va lent ne sta vo ve. gle da o ci su sve sni da je ne kim uče sni ca ma po treb ni ja ma te ri jal na i so ci jal na po dr ška, a ne in stant ose ćaj bla žen stva. mo že mo pret po sta vi ti da su i uče sni ce sve sne da le po ta ne će re ši ti sve nji ho ve pr o ble me, kao i da hi rur ški nož (još) ni je de lo- tvo ran u ise ca nju se ća nja na pr o ži vlje no. za po če tak, do volj no je iz gle da ti kao da ima ju sna ge da se sa pr o ble mi ma bo re. le pe. me đu tim, in du stri ja le po te ne op sta je za hva lju ju ći svo jim jed no krat nim, a do volj nim do bro čin stvi ma, već stal nim uvo đe- njem no vih tren do va ko ji zah te va ju kon stan tan (i udar nič ki) rad za le po tu. ti me se po tvr đu je ono što volf na zi va kva li fi ka ci jom pr o fe si o nal ne le po ti ce, po ziv ko jem se že ne oda zi va ju u sve ve ćem br o ju. vi di mo ih u re do vi ma is pred ki o ska sa zdra vom hra nom, u ma zo hi ji fit nes-cen ta ra, u spa-tret man skim ra je vi ma eli te i opre mi za džo ging. sva ko od nas ima pri ja te lji ce ko je se iz glad nju ju, ko je jed ne dru gi ma za vi de, ko je od ti nej džer- skog do ba ži ve ube đe ne u to da je je di no u trud no ći do zvo lje- no bi ti buc ma sta, ko je se pot pu no po sve ću ju mi si ji mr ša vlje nja ili ulep ša va nja. ovaj po sao sa pu nim rad nim vre me nom do la zi po sle pu nog rad nog vre me na maj ke, su pru ge ili po slov ne že ne, po put dru ge ili tre će pr o fe si je. (p)osta ti le pa zna či osta ti glad- na ne sa mo vi so ko ka lo rič ne hra ne, već i dru gih stva ri ko ji ma bi se že na mo gla po sve ti ti. (po sto ji gra ni ca ko ju mo del le po te me dij ski na met nut osta vlja u ma gli. to je gra ni ca iz me đu zdra- vlja i le po te, ali to ni je te ma ovog ra da.) ali, u ka ri je ri le po ti ce uspeh se go to vo ni kad ne do sti že traj no ni ti se pra šta. iako se i kroz mej ko ver emi si je na me će ide ja o mi tu o fe nik su, za pra vo je reč o si zi fo vom po slu. tre nu tak na vr hu br da ko šta pre vi še i tra je pre krat ko. spe ci fič na zam ka ko ja se po sta vlja, na ro či to za že ne ko je se pre- ma kri te ri ju mi ma po slov nog sve ta mo gu na zva ti uspe šnim ili “ostva re nim”, ka ko se to obič no zo ve, im pe ra tiv je da se iz gle da le po i ne go va no. mit o le po ti ta ko se po tvr đu je i pre ži vlja va, mo žda upra vo bru tal ni je me đu onim že na ma ko je su uspe šne, pre sve ga zbog mi šlje nja da one po se du ju svest o va žno sti po- ja ve i pri sta ju na pra vi lo da sva ko mi mo i la že nje sa “nor mom” pred sta vlja ne zna nje o ak tu el nim zah te vi ma este ti ke ili, još go re, sneŽana milin perkoviĆ ne mar ko ji od ra ža va le njost, ne za in te re so va nost ili ma lo du šnost kao sta nje du ha. im pli cit no se ova ide ja po ja vlju je i u ana li zi ra- noj emi si ji, po što su že ne ko je su pr o šle tran sfor ma ci ju pla stič- nom hi rur gi jom uglav nom ne za po sle ne ili za po sle ne na sla bo pla će nim po slo vi ma, ni su usme re ne na ka ri je ru, već na po ro di- cu, tr pe ili su tr pe le ne ki vid emo ci o nal ne i fi zič ke tra u me, pa, osim što je si tu a ci ja ko jom za slu žu ju ovu na gra du (le po tu), to pred sta vlja i iz go vor pred estet skim zah te vi ma kul tu re u ko joj ži ve. me đu tim, pr o blem ko ji ova emi si ja svo jom te mom po sta- vlja u pr vi plan oči ta va se u obr ta nju ta ko re ći uzroč ne ve ze, či me se uzrok ovog za ča ra nog kru ga pat nje na la zi u ne do stat ku ili gu bit ku le po te. po stav ši re še nje pr o ble ma, le po ta se isto vre me- no us po sta vlja kao uslov da se bu de us pe šan, da se iz beg ne ili uki ne pat nja. u dru štvu u ko jem se le po ta sve br že i jef ti ni je kon zu mi ra i ku pu je to po sta je i pra vi lo mno gih že na ko je pri- stu pa ju pr o me ni svog iz gle da pre ne go što pri stu pe iz grad nji svo je ka ri je re. ne tre ba za bo ra vi ti da mit o le po ti op sta je i po red kri ti ke na ra- čun hi rur gi je. vajs (we iss) i ku kla (ku kla) ka žu da ni je va žno šta hi rur gi ja mo že da bu de, već šta ona je ste, a ona per pe tu i ra kul tur no de fi ni san ideal le po te i po tvr đu je ga kao „nor ma lan“. ako stva ri po sta vi mo eks trem ni je, ne po sto ji le po ta ko ju že li- mo za se be, le po ta je uvek dru štve na kon ven ci ja i to ne mno go la ba vi ja od dru gih. mo gu će je pre i spi ta ti mo ti va ci ju i pri zna ti da po sto ji raz li ka iz me đu onih ko ji se pod vr ga va ju za hva ti ma na na go vor i oče ki va nje dru gih (bi lo iz lič nog ili pr o fe si o nal- nog okru že nja) i onih ko ji sma tra ju da to či ne „sa mo za se be“. me đu tim sa ma iz lo že nost po gle du uti če na mo ti va ci ju, i ti me u ovo is ku stvo i od lu ku uklju ču je ma lo vi še od sa me in di vi due. hi rur gi ja se mo že tu ma či ti kao mo guć nost sa mo tran sfor ma ci je i eman ci pa ci je (oslo bo đe nja) iz pri rod no da tog te la. ona mo že uki nu ti istin sku emo tiv nu pat nju, funk ci o nal ni pr o blem i ti me se iz jed na či ti za pra vo sa ko rek tiv nom hi rur gi jom. mo že mo pret- po sta vi ti da se, isto rij ski gle da no, ideal le po te (na ro či to žen ske) me njao i re de fi ni sao i da se na še do ba ne raz li ku je po ste pe nu na gla ša va nja sop stve nih estet skih “nor mi”. ta ko đe je ve ro vat- no da se le po ta na raz li či te na či ne po ve zi va la sa onim što se u tom tre nut ku sma tra lo zdra vim. spe ci fič nost sa vre me nog do ba je u mno štvu i ra zno li ko sti po gle da ko ji ma je te lo iz lo že no. ako iz u zme mo te žnju ka he ro in skom ši ku i ano rek sič nom, pol no ne- de fi ni sa nom te lu, ko je po ku ša va da uba ci mod na in du stri ja, mo- že mo sa svim po jed no sta vlje no re ći da da nas, iz žen skog vid nog po lja, ni jed no te lo ni je do volj no mr ša vo, dok za mu škar ce ne po sto ji gra ni ca u ve li či ni gru di. da na šnji uslo vi ži vo ta omo gu ću ju bo lju i ra zno vr sni ju ne gu sop- stve nog te la, estet ski i zdrav stve no. hi rur gi ja je za pra vo samo sneŽana milin perkoviĆ jed na od no vih me to da da se ostva ri dru štve no pr o pi sa ni cilj. ma ši ne ri ja le po te ob u hva ta i či ta vu armi ju dru gih: ko zme ti ča re, nu tri ci o ni ste, fit nes i spa cen tre, sti li ste i osta le ko ji su sprem ni da po mog nu u ovoj bor bi. rad na le po ti je ve o ma an ga žu ju ći, pa je za ni mlji vo to što mno ge že ne ovo fi zič ko i psi hič ko preg- nu će vi de kao na čin da se “po sve te se bi” i “uči ne ne što sa mo za se be”. ta ko se plan ozna čen re či ma “od ri ca nje”, “re strik tiv ni re žim” i “ri go ro zna di je ta” iz jed na ča va sa auto nom no šću i slo- bo dom (za hva lju ju ći hi rur gi ji i ko zme ti ci sva ka že na je “slo bod- na da bu de le pa”). ali, zar pra vo oslo bo đe nje ne bi pod ra zu me- va lo da je sva ka že na već le pa (na bi lo ko ji na čin) ili da to ni je ni va žno (ili bar ne pre sud no)? u svo joj knji zi, na o mi volf ne kri ti ku je ono što že na ma po ma že da se ose ća ju do bro, već ono zbog če ga se u star tu ose ća ju lo še. ni je pr o blem uči ni ti ne što za le po tu i ose ća ti se do bro zbog to ga, pr o blem je što se ose ća mo lo še jer mi sli mo da ni smo le pe. pr o blem je ne do sta tak stvar nog iz bo ra. ako i pri sta ne mo da hi rur gi ju po sma tra mo kao lek, ni je ključ no da se za pi ta mo o va lja no sti le ka, već zbog če ga se ono što on le či uop šte sma tra bo le šću. li te ra tu ra: ber v., uvod u so ci jal ni kon struk ci o ni zam, zep ter bo ok world, be o- grad . bor do s., twenty years in the twi light zo ne, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as hga te pu blis hing ltd, far nham . da vis k., re vi si ting fe mi nist de ba tes on co sme tic sur gery: so me re flec ti ons on suf fe ring, agency and em bo died dif fe ren ce, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as- hga te pu blis hing ltd, far nham . fa lu di s., za sve je kriv fe mi ni zam, u: Ča so pis za fe mi ni stič ku te o ri ju ge ne ro br. , cen tar za žen ske stu di je, be o grad . fra ser s., agency ma de over? co sme tic sur gery and fe mi ni nity in wo men`s ma ga zi nes and ma ke o ver te le vi sion, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as hga te pu blis hing ltd, far nham . hall s., the work of re pre sen ta tion, in: re pre sen ta tion: cul tu ral re pre sen ta tion and sig nifying prac ti ces, eds. stu art hall, sa ge, lon don . heyes c. j. i jo nes m., co sme tic sur gery in the age of gen der, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as- hga te pu blis hing ltd, far nham . me jer a. k. i van zo nen l., od brit ni spirs do era zma: že ne, mu škar- ci i nji ho vo pri ka zi va nje, u: stu di je kul tu re – zbor nik, pri re dio Đor đe- vić j., slu žbe ni gla snik, be o grad . sneŽana milin perkoviĆ mi li vo je vić s., Že ne i me di ji: stra te gi je is klju či va nja, u: Ča so pis za fe mi ni stič ku te o ri ju ge ne ro, po seb no iz da nje, pri re dio mi li vo je vić s., cen tar za žen ske stu di je, be o grad . mor gan k. p., wo men and the kni fe: co sme tic sur gery and the co- lo ni za tion of the wo men`s body, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as hga te pu blis hing ltd, far nham . we iss d. i ku kla r., the ’na tu ral lo ok’: ex tre me ma ke o ver and the li mits of self-fas hi o ning, in: co sme tic sur gery, a fe mi nist pri mer, eds. heyes c. j. i jo nes m., as hga te pu blis hing ltd, far nham . wolf n., the be a uty myth, har per col lins, new york . van zo nen l., no ve te me, Ča so pis za fe mi ni stič ku te o ri ju ge ne ro, po seb no iz da nje, pri re dio mi li vo je vić s., cen tar za žen ske stu di je, be o grad . snežana milin perković university of belgrade, faculty of political sciences, belgrade makeover television and the beauty myth abstract the media have an important role in communicating cultural values and ideas, but they also affect the outlining and defining the concepts of beauty. therefore, the media representation processes are key to forming cultural “norms” of a beautiful female body, while consumption oriented society finds esthetic surgery a simpler and faster way of democratizing and achieving this ideal. as a mixture of the mentioned motives, the makeover television is an example of media content whose analysis can uncover the meanings and affirmation mechanisms of the contemporary beauty myth - an idea suggested by naomi wolf. these tv shows can be viewed as particular media rituals, initiating into the myth and legitimizing its social role. reality makeover tv show moje novo ja, aired on prva television, is analysed to uncover the key moments of media representation of current idea(l)s of a desired woman`s beauty, the consequences of such ideas and the social power relations which the myth itself portrays. keywords: makeover tv, media representation, the beauty myth beauty contests and irrational exuberance: a neoclassical approach∗ george-marios angeletos mit and nber guido lorenzoni mit and nber alessandro pavan northwestern university march , abstract the arrival of new, unfamiliar, investment opportunities is often associated with “exuberant” movements in asset prices and real economic activity. during these episodes of high uncertainty, financial markets look at the real sector for signals about the profitability of the new investment opportunities, and vice versa. in this paper, we study how such information spillovers impact the incentives that agents face when making their real economic decisions. on the positive front, we find that the sensitivity of equilibrium outcomes to noise and to higher-order uncertainty is amplified, exacerbating the disconnect from fundamentals. on the normative front, we find that these effects are symptoms of constrained inefficiency; we then identify policies that can improve welfare without requiring the government to have any informational advantage vis-a-vis the market. at the heart of these results is a distortion that induces a conventional neoclassical economy to behave as a keynesian “beauty contest” and to exhibit fluctuations that may look like “irrational exuberance” to an outside observer. keywords: mispricing, heterogeneous information, information-driven complementarities, volatil- ity, inefficiency, beauty contests. ∗this paper subsumes and extends an earlier paper that circulated as a nber working paper under the title “wall street and silicon valley: a delicate interaction.” we thank olivier blanchard, stephen morris, hyun song shin, rob townsend, jaume ventura, iván werning, and seminar participants at mit, the federal reserve board, the federal reserve bank of boston, the iese conference on complementarities and information (barcelona), the minnesota workshop in macroeconomic theory, and the nber summer institute for useful comments. angeletos and pavan thank the nsf for financial support. email addresses: angelet@mit.edu; glorenzo@mit.edu; alepavan@northwestern.edu. introduction the arrival of new, unfamiliar, investment opportunities—e.g., a novel technology like the internet in the late s, or new markets in emerging economies—is often associated with large joint move- ments in asset prices and real economic activity. many observers find these movements hard to rec- oncile with fundamentals. instead, they interpret them as temporary waves of “exuberance” which appear to get reinforced as market participants look at one another’s behavior for clues regarding the profitability of the new investments. furthermore, financial markets are blamed for playing a destabilizing role, as the agents in charge of real investment decisions become “overly” concerned about the short-run valuation of their capital instead of paying attention to the fundamentals—a popular argument that can be traced back to keynes’ famous “beauty contest” metaphor. understanding these episodes, while also capturing the aforementioned ideas, requires moving away from the neoclassical paradigm of efficient markets: within this paradigm, there is no room for “exuberance,” “sentiments,” and the like; asset prices only reflect the underlying fundamentals; and it is irrelevant whether real investment decisions are driven by fundamentals or by asset prices. a simple alternative is to assume that the observed phenomena are driven, to a large extent, by the beliefs and the behavior of irrational agents. we do not go in that direction here. instead, we maintain the axiom of rationality; we depart from the neoclassical paradigm only by introduc- ing dispersed information; and we focus on the information spillovers that emerge when financial markets look at real economic activity as a signal of the underlying fundamentals. this modeling approach reflects, in part, a matter of preferred methodology. we are uncom- fortable with policy prescriptions that rely heavily on the presumption that the government has a superior ability to evaluate the economy’s fundamentals, relative to the market mechanism. most importantly, it helps us capture two important aspects of the phenomena of interest: that infor- mation is likely to be particularly dispersed because of the absence of previous social learning; and that market participants seem anxious to look at one another’s behavior, and at various indicators of economic activity, for clues about the underlying profitability. our contribution is then to study how such information spillovers impact the incentives that agents face when making their real investment decisions. first, we find that the response of the economy to noise is amplified, exacerbating the disconnect from fundamentals. second, we find that these effects are symptoms of inefficiency even relative to a constrained planning problem that respects the diversity of beliefs and the dispersion of information. combined, these results provide a theory of rational exuberance and uncover a mechanism that induces an otherwise conventional neoclassical economy to behave like a keynesian beauty contest. see, e.g., lucas ( ) and abel and blanchard ( ). cecchetti et al. ( ), shiller ( ), bernanke and gertler ( ), dupor ( ), akerlof and shiller ( ). preview of model and results. the real sector of our model features a large number of “entrepreneurs” who each must decide how much to invest in a new technology on the basis of im- perfect, and heterogeneous, information about the profitability of this technology. in a subsequent stage, but before uncertainty is resolved, these entrepreneurs may sell their capital in a competitive financial market. the “traders” in this market are also imperfectly informed, but get to observe a signal of the entrepreneurs’ early investment activity. at the core of this model is a two-way interaction between financial markets and the real econ- omy. on the one hand, entrepreneurs base their initial investment decisions on their expectations of the price at which they may sell their capital. this captures more broadly the idea that the agents in charge of real investment decisions—be they the ceo of a public corporation, or the owner of a start-up—are concerned about the future market valuation of their capital. on the other hand, traders look at the entrepreneurs’ activity as a signal of the profitability of the new investment opportunity. this captures more broadly the idea that financial markets follow closely the release of macroeconomic and sectoral data, and constantly monitor corporate outcomes, looking for clues about the underlying economic fundamentals. the first effect represents a pecuniary externality that, as in any walrasian setting, is not by itself the source of any distortion. the second effect identifies an information spillover that is at the heart of our positive and normative results. on the positive side, we identify a mechanism that amplifies the response of the economy to noise relative to fundamentals. by “fundamentals” we mean the profitability of the new investment opportunity (or, more broadly, technologies, preferences and endowments). by “noise” we mean any source of variation in equilibrium outcomes that is orthogonal to the fundamentals. in our model, such non-fundamental variation can originate from correlated errors in information about the fundamentals; from higher-order uncertainty; and, in certain cases, from sunspots. to understand this result, consider the case where “noise” originates from correlated errors in the entrepreneurs’ information; this is the case we concentrate on for the bulk of our analysis. suppose for a moment that the entrepreneurs’ decisions were driven merely by their opinions about the fundamentals. in equilibrium, aggregate investment would then depend on the entrepreneurs’ average opinion and would therefore send a signal to the financial market about the underlying fundamentals. in general, this signal is going to be noisy: any given agent—be he a trader or an entrepreneur—may not be able to tell whether high aggregate investment is caused by a positive shock to fundamentals, or by a positive correlated error in the entrepreneurs’ opinions. nevertheless, relative to the typical trader, the typical entrepreneur is bound to have superior information about the noise in this signal. this is because the signal itself is the collective choice of the entrepreneurs; the noise in this signal thus originates in the entrepreneurs’ own private information. in effect, the entrepreneurs, as a group, are playing a signaling game vis-a-vis the traders. this observation is crucial, for it implies that the (rational) pricing errors that occur in the finan- cial market are partly predictable by the typical entrepreneur. in particular, whenever there is a pos- itive correlated error in the entrepreneurs’ information about the fundamentals, each entrepreneur will expect the average opinion of the other entrepreneurs—and hence aggregate investment—to increase more than his own opinion. but then the entrepreneur will also expect the financial market to overprice his capital. this in turn creates a speculative incentive for the entrepreneur to invest more than what warranted from his expectation of the fundamentals—and thereby to engage in what may look like “exuberant” investment to an outside observer. as all entrepreneurs do the same, their collective “exuberance” may trigger asset prices to inflate, because the traders will perceive this exuberance in part as a signal of good fundamentals. the anticipation of inflated prices can feed back to further exuberance in real economic activity, and so on. this argument highlights more generally the role of higher-order uncertainty between the agents participating in the real and in the financial sector of the economy. within the context of our model, this means the following. when an entrepreneur decides how much to invest, he must form beliefs about the traders’ beliefs about the fundamentals in order to predict the price at which he will be able to sell his capital in the financial market. a trader, in turn, must form beliefs about the entrepreneurs’ beliefs in order to interpret the signal conveyed by aggregate investment. it follows that investment and asset prices are driven by the higher-order beliefs of both these two groups. the key contribution of our analysis is in highlighting how the information spillovers between the two sectors of the economy may heighten the impact of such higher-order uncertainty on investment and asset prices, thereby exacerbating their disconnect from fundamentals, while also providing a micro-foundation to keynes’ “beauty contest.” interestingly, these effects obtain without any of the agents being strategic, in the sense that they are all infinitesimal and take prices and aggregate outcomes as exogenous to their choices. thus, despite a certain similarity in flavor, our results are distinct from those in the financial microstructure literature, which, in the tradition of kyle ( ), focuses on how large players can manipulate asset prices. rather, the manipulation effects in our model are the by-product of the “invisible hand”, that is, of the general-equilibrium interaction of multiple small players. turning to the normative side, the question of interest is whether the aforementioned positive results are also symptoms of inefficiency. this question is central to our formalization of “exuber- ance” and “beauty contests,” for these ideas typically involve a, more or less explicit, judgement that something is going “wrong” in the market and that the government should intervene. to address this question, we consider the problem faced by a planner who has full power on the agents’ incentives but has no informational advantage vis-a-vis the market—either in the form of see, e.g., goldstein and guembel ( ), which emphasizes how this manipulation could distort real investment. additional information, or in the form of the power to centralize the information that is dispersed in the economy. we then show that this planner would dictate to the entrepreneurs to ignore the expected mispricing in the financial market and all the consequent higher-order uncertainty, and instead base their investment decisions solely on their expectations of the fundamentals. this is because any gain that the entrepreneurs can make by exploiting any predictable mispricing is only a private rent—a zero-sum transfer from one group of agents to the other, which only creates a wedge between the private and social return to investment. it follows that our positive results have a clear normative counterpart. we conclude our analysis by identifying policies that improve welfare even when the government is restricted to use only information that is already in the public domain. we first show how simple policies that stabilize asset prices, like those often advocated in practice, can lead to higher welfare; but we also identify some important limitations of such policies. we then discuss how certain more sophisticated policies can do better, possibly restoring full efficiency. related literature. morris and shin ( ) recently put forth the idea that models that combine strategic complementarity with dispersed information can capture the role of higher-order uncertainty in keynes’ beauty contest metaphor, spawning a rich literature. however, by lacking specific micro-foundations, this earlier work did not address the positive question of what is the origin of strategic complementarity, and the normative question of what is the cause of the ineffi- ciency of the equilibrium, if any. subsequent work by allen, morris and shin ( ), bacchetta and wincoop ( ), and cespa and vives ( ) has addressed the positive question within the context of dynamic asset-pricing models, but has abstracted from real economic activity and has left aside the normative question. relative to this literature, our contribution is to address the aforemen- tioned questions within a micro-founded, neoclassical framework of the interaction between real and financial activity. what opens the door to non-trivial effects from higher-order uncertainty in our setting is the combination of trading and information spillovers among different groups of agents (the en- trepreneurs and the traders). in this respect, our formalization of “beauty contests” is connected to townsend ( ), who was the first to highlight the role of higher-order beliefs in settings with dispersed information and endogenous learning. but while townsend studied a framework with no trade and no other payoff links across agents, our results rest on the presence of trading opportu- nities: if the entrepreneurs never sold their capital in the financial market, both the amplification and the inefficiency would vanish. our paper also connects to the voluminous literature on herding and social learning (e.g., amador and weill, ; banerjee, ; chamley, ; vives, ). we share with this liter- this planning problem builds on the notion of constrained efficiency studied in angeletos and pavan ( , ) for a class of environments with dispersed information. ature the broader idea that the economy may feature heightened sensitivity to certain sources of information, leading to increased non-fundamental volatility; see especially chari and kehoe ( ) for an application to financial markets and loisel, pommeret and portier ( ) for an application to investment booms. however, the mechanism we identify is distinct. the key distortion featured in this literature is the failure of individual agents to internalize the impact of their own actions on the information available to other agents, which in turn affects the efficiency of the decisions taken by the latter. instead, in our model, the key distortion is the one that rests on how the antici- pation of the signaling role of investment affects the entrepreneurs’ incentives. in this regard, the mechanics are more closely related to those in the signaling literature (e.g., spence, ) than to those in the herding literature. note, though, that the “senders” in our model (the entrepreneurs) are non-strategic in the sense that the actions of each one alone do not affect the beliefs of the “re- ceivers” (the traders); it is only the collective behavior of the former, coordinated by an “invisible hand”, that affects the beliefs of the latter. our paper also adds to the growing macroeconomic literature on dispersed information. our contribution in this regard is to identify novel positive and normative implications of the two-way interaction between real and financial activity. closely related in this regard is the recent paper by goldstein, ozdenoren and yuan ( ). this paper focuses on the opposite information spillover, namely from the financial market to the real sector. in so doing, it complements our paper, but it does not consider the amplification and inefficiency effects that are at the core of our contribution. tinn ( ) considers an informational spillover similar to the one in our paper, but within a setting that does not feature our amplification and inefficiency results. la’o ( ) studies a model where the two-way interaction between real and financial activity rests on collateral constraints, as in kiyotaki and moore ( ), rather than information spillovers, as in our paper. finally, by touching on the broader themes of heterogeneous beliefs, speculation, and mispricing, our paper connects to scheinkman and xiong ( ), panageas ( ), and geanakoplos ( ). this line of work abstracts from asymmetric information and instead models the heterogeneity of beliefs with heterogeneous priors. by abstracting from asymmetric information, this literature rules out the information spillovers that are at the core of our positive and normative results. our results, on the other hand, are driven by the asymmetry of information, but do not hinge on the assumption of a common prior: they can be extended to settings with multiple priors, provided that one allows for endogenous learning stemming from the presence of dispersed information. layout. the rest of the paper is organized as follows. section introduces the model. section characterizes the equilibrium and delivers the key positive results. section discusses how our results provide a neoclassical formalization of “exuberance” and “beauty contests”. section see, e.g., amador and weill ( ), angeletos and la’o ( a), hellwig ( ), lorenzoni ( ), mackowiak and wiederholt ( ), mankiw and reis ( ), veldkamp ( ), and the references therein. characterizes the constrained efficient allocation, it contrasts it to the equilibrium, and discusses policy implications. section discusses possible extensions that may help reinforce the message of the paper. section concludes. appendix a contains all proofs, while appendix b proves the robustness of our results to richer payoff and information structures. the model our model features a single round of real investment followed by a single round of financial trading, with information flowing from the former to the latter. the economy is populated by two types of agents, “entrepreneurs” and “traders.” each type is of measure / ; we index entrepreneurs by i ∈ [ , / ] and traders by i ∈ ( / , ]. timing and key choices. time is divided in four periods, t ∈ { , , , }. at t = , a new investment opportunity, or “technology,” becomes available. the profitability of this technology is determined by a random variable θ̃. this random variable defines the “fundamentals” in our model. it is drawn from a normal distribution with mean µ > and variance /πθ, which defines the common prior (with πθ being the precision). the realization θ of this random variable is unknown to all agents. at t = , the “real sector” of the economy operates: each entrepreneur gets the opportunity to invest in the new technology. let ki denote the investment of entrepreneur i. the cost of this investment in terms of the consumption good is k i / . when choosing investment, entrepreneurs have access to various sources of information (signals) that are not directly available to the traders. the noise in some of these signals may be mostly idiosyncratic, while for other signals the noise may be correlated across entrepreneurs. we consider a general information structure along these lines in appendix b. here, to simplify, we let the entrepreneurs observe only two signals. the one has purely idiosyncratic noise: it is given by xi = θ + ξi, where ξ̃i is gaussian noise, independently and identically distributed across agents, independent of θ̃, with variance /πx. the other has perfectly correlated noise: it is given by y = θ + ε, where ε̃ is gaussian noise, common across entrepreneurs, independent of θ̃ and of {ξ̃i}i∈[ , / ], with variance /πy. the key role of the correlated error ε̃ is to introduce a source of non-fundamental movements in aggregate investment. throughout, we use “tildes” to denote random variables and drop them when denoting realizations. one can easily reinterpret this cost as the disutility of effort necessary to produce ki. such a correlated error, in turn, can have various origins. as discussed in section . , private signals about the actions of agents that moved in the past may lead in equilibrium to signals about θ with correlated errors. more broadly, network effects, social learning, and information cascades may also explain this correlation. alternatively, as emphasized in hellwig and veldkamp ( ) and myatt and wallace ( ), strategic complementarity—like the one that, as we will show, emerges endogenously in our economy—by itself generates an incentive for the agents to collect correlated sources of information. see also dow, goldstein, and guembel ( ), froot, scharfstein, and stein ( ), and veldkamp ( ) for complementary justifications. at t = , the “financial market” operates: some entrepreneurs transfer their capital to the traders. these trades may be motivated by a variety of reasons unrelated to private information. to keep the analysis tractable, we model these trades as follows. each entrepreneur is hit by an idiosyncratic shock with probability λ ∈ [ , ]. entrepreneurs hit by this shock do not value consumption at t = and have no choice but to sell all their capital at t = . for simplicity, the entrepreneurs not hit by the shock are precluded from trading; this last assumption can be relaxed provided that the equilibrium price does not become perfectly revealing (see the discussion in section . ). from now on, we refer to this shock as a “liquidity shock”; but we think of it more broadly as a modeling device that helps us capture the concern that the agents in charge of real investment have about future equity prices. the financial market is competitive and the market-clearing price is denoted by p. when the traders meet the entrepreneurs hit by the liquidity shocks in the financial market, they observe the quantity of capital that these entrepreneurs bring to the market. since λ is known, this is equivalent to observing the aggregate level of investment, k ≡ ∫ kidi. this is meant to capture more broadly other signals that the real sector may be sending to the financial market, including preliminary production and sale data. the traders then use this observation to update their beliefs about θ. any other information that the traders may have about the fundamentals is summarized in a public signal ω = θ + η, where η̃ is gaussian noise, independent of θ̃, ε̃ and {ξ̃i}i∈[ , / ], with variance /πω. while ω is modeled here as an exogenous signal, it is straightforward to reinterpret it as the outcome of the aggregation of information that may take place in the financial market when the traders have dispersed private signals about θ. finally, at t = , the fundamental θ is publicly revealed and production takes place using the new technology and the installed capital. to simplify the exposition, we assume that each unit of capital delivers θ units of the consumption good, irrespective of whether it is held by an entrepreneur or by a trader. (see section . and appendix b for extensions that allow for richer technologies and for the marginal product of capital to depend on its ownership.) preferences, endowments, and markets. all agents receive an exogenous endowment e of the (nonstorable) consumption good in each period. moreover, they are risk neutral and their discount rate is zero: preferences are given by ui = ci + ci + sici , where cit denotes agent i’s consumption in period t, while s̃i is a random variable that takes value if the agent throughout, we do not explicitly model the distinction between trading financial claims over the installed capital and trading the capital goods themselves; in our framework, this distinction is irrelevant. an alternative way to introduce this concern within the context of start-ups rests on the presence of efficiency gains from transferring capital ownership from the agents who have a comparative advantage in starting a new company to the ones who have a comparative advantage in running it at later stages of development (e.g., holmes and schmitz, ). in equilibrium, the cross-sectional distribution of ki is normal with known variance; observing the mean level, k, is thus informationally equivalent to observing the entire cross-sectional distribution of investment. is an entrepreneur hit by a liquidity shock and value otherwise. finally, in addition to the aforementioned financial market, we allow the following markets to operate in each period: a market for the consumption good (which is also the numeraire); a market for a riskless bond; and a market for insurance contracts on the entrepreneurs’ idiosyncratic liquidity shocks. given the assumption of risk neutrality, these additional markets will be irrelevant for either investment decisions or asset prices in equilibrium. rather, they are introduced so as to clarify that the only essential market imperfection we impose is the one that limits the aggregation of information about the fundamentals—our results will not be driven by borrowing constraints, incomplete risk-sharing, and the like. equilibrium because of the assumptions of linear preferences and zero discounting, the equilibrium risk-free rate is zero in all periods and all states; the consumption allocations and the trades of bonds and insurance contracts are indeterminate; and the agents’ expected utility reduces to the expected present value of their net income flows. for entrepreneurs hit by the liquidity shock, net income flows sum up to e+pki−k i / , while for entrepreneurs not hit by the shock (henceforth also referred to as “surviving entrepreneurs”), they sum up to e+θki−k i / . therefore, each entrepreneur’s expected utility at the time of investment is given, up to a constant, by e[ũi|xi,y] = e[( −λ)θ̃+λp̃− k i |xi,y]. since this objective is strictly concave, the investment choice of an entrepreneur can be expressed as a function of x and y, the two signals observed by the entrepreneur. aggregate investment is then a function of two aggregate shocks, the fundamental θ and the correlated error ε. a trader’s net income flow, on the other hand, is given by e + θqi − pqi, where qi denotes the position he takes in the financial market. since the trader observes the exogenous signal ω and the aggregate capital k, his expected utility at the time of trading is, up to a constant, e[ũi|k,ω] = (e[θ̃|k,ω] − p)qi. it follows that the market-clearing price in the financial market is pinned down by the traders’ expectation of the fundamental: p = e[θ̃|k,ω]. since k is a function of (θ,ε) and ω = θ + η, the equilibrium price can be expressed as a function of (θ,ε,η). with all these observations in mind, we define our equilibrium concept as follows. definition a (linear rational-expectations) equilibrium is an individual investment strategy k(x,y), an aggregate investment function k(θ,ε), and a price function p(θ,ε,η) that jointly satisfy the fol- lowing conditions: since no trader has private information and the entrepreneurs who sell their capital have perfectly inelastic supplies, the market-clearing price does not reveal any information, which explains why we omit conditioning on p when describing the traders’ expectations. also, any value k ∈ r can be observed in equilibrium, which explains why we do not have to worry about describing out-of-equilibrium beliefs. (i) for all (x,y), k (x,y) ∈ arg max k e [ ( −λ)θ̃k + λp(θ̃, ε̃, η̃)k − k ∣∣∣ x,y ] ; (ii) for all (θ,ε), k(θ,ε) = ∫ k (x,y) dΦ(x,y|θ,ε), where Φ(x,y|θ,ε) denotes the joint cumulative distribution function of x and y, given θ and ε; (iii) for all (θ,ε,η), p (θ,ε,η) = e [ θ̃ ∣∣∣ k, ω ] , where k = k(θ,ε) and ω = θ + η; (iv) there exist scalars β , βθ and βε such that, for all (θ,ε), k(θ,ε) = β + βθθ + βεε. condition (i) requires that the entrepreneurs’ investment strategy be individually rational, taking as given the equilibrium price function. condition (ii) is just the definition of aggregate investment. condition (iii) requires that the equilibrium price be consistent with market clear- ing and rational expectations on the traders’ side, taking as given the collective behavior of the entrepreneurs. finally, condition (iv) imposes linearity; as usual in the rational-expectations liter- ature, this linearity is necessary for maintaining tractability. (in our setting, linearity of the price function implies linearity of the aggregate investment, and vice versa.) to simplify the language, we henceforth drop the qualifications “linear” and “rational-expectations” and refer to our equilib- rium concept simply as “equilibrium”. also, we refer to θ and ε as, respectively, the “fundamental shock” and the “noise shock”, and to the coefficients βθ and βε as the“responses” of aggregate investment to these shocks. . a benchmark with no information spillovers for comparison purposes, we now consider a case in which the information spillover between the real and the financial sector is absent. in particular, suppose that the noise in the traders’ signal ω vanishes (πω →∞), so that θ is known at the time of trading and the signaling role of k vanishes. the financial market then clears if and only if p = θ and, by implication, the expected payoff of an entrepreneur who receives signals x and y is simply e[θ̃|x,y]k − k / . it follows that the entrepreneur’s optimal investment is pinned down by his expectation of θ: k (x,y) = e[θ̃|x,y] = δ + δxx + δyy where δ ≡ π π µ, δx ≡ πx π , δy ≡ πy π , and π ≡ π + πx + πy. by implication, aggregate investment is given by k(θ,ε) = δ + δθθ + δεε, where δθ ≡ δx + δy and δε ≡ δy. proposition in the absence of information spillovers, the equilibrium is unique and investment is pinned down merely by the entrepreneurs’ expectations of the fundamentals. this result establishes that, in the absence of information spillovers, it is irrelevant for equilib- rium outcomes whether investment is driven by the entrepreneurs’ expectations of the fundamental or by their expectations of the asset price. in this respect, our economy behaves like any con- ventional neoclassical economy, leaving no room for the features of a keynesian beauty contest. importantly, this result does not require θ to be known by the traders; it applies more generally as long as the information that the traders possess about θ is a sufficient statistics for this infor- mation and for the one that the entrepreneurs as a group possess, in which case the entrepreneurs’ behavior cannot possibly convey any additional information about θ. from now on, we refer to this benchmark as the case with no information spillovers. . information spillovers we now turn attention to the case of interest, namely when the real sector sends valuable signals to the financial market. below, we first describe how any equilibrium can be understood as a fixed point between the aggregate investment function (which summarizes the collective behavior of the real sector) and the asset price function (which summarizes the collective behavior of the financial market), focusing on the situations where aggregate investment is increasing in both the fundamentals and the noise (i.e., where βθ > and βε > ). we then prove that an equilibrium with this property always exists and is unique for λ small enough. take an arbitrary linear aggregate investment function of the form k (θ,ε) = β + βθθ + βεε, for some coefficients β , βθ and βε. a central object in our analysis is the response of aggregate investment to noise relative to the fundamental, defined as the ratio ϕ ≡ βε βθ . ( ) from the perspective of an outside observer, this ratio determines the fraction of the overall volatil- ity in aggregate investment that cannot be explained by fundamentals. formally, ϕ is inversely to clarify this point, consider an arbitrary information structure. let i be the exogenous information of traders at t = (i.e., the information not inferred through k). next, let ii be the information of entrepreneur i at t = . finally, let i ≡∪i∈[ , / ]ii and assume that i is a sufficient statistics for (i ,i ) with respect to θ̃. this assumption implies that e[θ̃|i ,i ] = e[θ̃|i ]. because k is measurable in i , this also implies that p = e[θ̃|i ,k] = e[θ̃|i ]. by the law of iterated expectations, we then have that e[p̃|ii ] = e[e[θ̃|i ,i ]|ii, ] = e[θ̃|ii ] for all i ∈ [ , / ]. it follows that every entrepreneur chooses ki = e[θ̃|ii ]. related to the r-square of the regression of the realized k on the realized θ. from the perspec- tive of a trader in the model, on the other hand, ϕ determines the informativeness of the signal that the financial market receives from the real sector. indeed, as long as βθ = , observing k is informationally equivalent to observing the following gaussian signal about θ: z ≡ k −β βθ = θ + ϕε. ( ) it follows that ϕ pins down the noise-to-signal ratio in aggregate investment: this ratio is simply v ar(ϕ�)/v ar(θ) = ϕ πθ/πy. we henceforth refer to ϕ interchangeably as the “relative response to noise” and as the “noise-to-signal ratio.” now, put aside for a moment the endogeneity of the aforementioned signal, assume that the traders observe a signal of the form z = θ + ϕε for some arbitrary ϕ ∈ r, and consider the determination of the asset price. bayesian updating implies that the traders’ expectation of θ is a weighted average of their prior mean µ and their two signals ω and z: e[θ̃|k,ω] = e[θ̃|z,ω] = πθ πθ+πω+πz µ + πω πθ+πω+πz ω + πz πθ+πω+πz z, ( ) where πθ, πω, and πz ≡ πy/ϕ are the precisions of, respectively, the prior, the signal ω, and the signal z. by implication, the equilibrium asset price can be expressed as follows: p (θ,ε,η) = γ + γθθ + γεε + γηη, ( ) where γθ ≡ πω+πy/ϕ πθ+πω+πy/ϕ , γε ≡ πy/ϕ πθ+πω+πy/ϕ ϕ, and γη ≡ πωπθ+πω+πy/ϕ measure the responses of the asset price to the underlying shocks. importantly, these responses depend on ϕ: because a higher ϕ means more noise in the signal z but also less sensitivity of the traders’ expectation of θ to this signal, a higher ϕ necessarily reduces the response of the price to the fundamental θ and increases its response to the noise η, while it has a non-monotonic effect on its response to the noise ε. next, consider the incentives faced by the entrepreneurs when they expect the asset price to satisfy ( ). optimality requires that individual investment satisfies the following condition for all x and y: k (x,y) = e [ ( −λ)θ̃ + λp(θ̃, ε̃, η̃) ∣∣∣x,y] . ( ) substituting the asset price from ( ) into the entrepreneur’s optimality condition ( ), and noting that the conditional expectations of θ and ε are linear functions of the signals x and y, while the conditional expectation of η is zero, we infer that individual investment can be expressed as a linear function of the two signals: k (x,y) = β′ + β ′ xx + β ′ yy, for some coefficients β ′ , β ′ x and β′y. importantly, these coefficients depend on ϕ through ( ), capturing the impact that the anticipated price behavior has on individual investment incentives. finally, aggregating across the entrepreneurs gives k (θ,ε) = β′ + β ′ θθ + β ′ εε, with β ′ θ = β ′ x + β ′ y and β ′ ε = β ′ y. it follows that the signal sent by the real sector can be expressed as z′ = θ + ϕ′ε, with noise-to-signal ratio given by ϕ′ = β′ε/β ′ θ. the latter is pinned down by the relative response of individual investment to the two signals x and y, which in turn depends on ϕ through ( ). putting the aforementioned arguments together, we infer that any equilibrium can be under- stood as a fixed point to a function Γ that maps each ϕ ∈ r to some ϕ′ ∈ r. this mapping, which is formally defined in the appendix, has a simple interpretation: when the financial market receives a signal z = θ +ϕε with noise-to-signal ratio given by some arbitrary ϕ ∈ r, the real sector responds by sending a signal z′ = θ + ϕ′ε with noise-to-signal ratio given by ϕ′ = Γ(ϕ). of course, in any equilibrium the signal received by the financial market must coincide with the signal sent by the real sector, which explains why the fixed points of the mapping Γ identify the equilibria of our economy. studying the properties of this mapping then permits us to reach the following result, which concerns the existence and uniqueness of equilibria in our model. proposition there always exists an equilibrium in which the coefficients βx,βy,βθ,βε,γθ,γε,γη are all positive. furthermore, there exists a cutoff λ̄ > , such that, for any λ < λ̄, this is the unique equilibrium. we conclude that there always exists an equilibrium in which individual investment responds positively to both the signals x and y and, by implication, aggregate investment responds positively to both the fundamentals θ and the noise ε. whenever this is the case, the equilibrium asset price also responds positively to both θ and ε. this is because the traders (correctly) perceive high investment as “good news” about profitability, but cannot distinguish between increases in investment driven by θ from those driven by ε. . . mispricing, speculation, and amplification we now turn to our main positive result, regarding the relative response of equilibrium investment to noise. to this purpose, it is useful to rewrite the entrepreneur’s optimal investment as follows: ki = ei[θ̃] + λei[p(θ̃, ε̃, η̃) − θ̃] = ei[θ̃] + λei[et[θ̃] − θ̃], ( ) where ei and et are short-cuts for the conditional expectations of, respectively, entrepreneur i and the traders. this condition has a simple interpretation. the variable θ represents the fundamental valuation of a unit of capital. the gap p−θ = et[θ̃]−θ thus identifies the traders’ forecast error of that valuation, or the “pricing error” in the market. the component of investment that is driven by the forecast of this pricing error can then be interpreted as “speculative.” for any given expectation of θ, an entrepreneur will invest more in response to a positive expectation of the traders’ forecast error; this is because he expects to sell the extra capital in an “overpriced” market. that entrepreneurs base their investment decisions both on their expectation of their fundamen- tal valuation and on their expectation of the financial price should not surprise. this property holds in any environment where entrepreneurs have the option to sell their capital in a financial market. in particular, this property also applies to the benchmark with no information spillovers. what distinguishes the present case from that benchmark is that the entrepreneurs possess information that permits them to forecast the traders’ pricing error. this possibility rests on two properties: (i) that the traders look at aggregate investment as a signal of the underlying fundamental; and (ii) that the entrepreneurs possess additional information about the sources of variation in their investment choices. in particular, note that, for given θ, a positive realization of the noise shock ε in the entrepreneurs’ information causes a boom in aggregate investment. since the traders cannot tell whether this boom was driven by a strong fundamental or by noise, they respond to this investment boom by bidding the asset price up. however, relative to the traders, the entrepreneurs have superior information about the origins of the investment boom. this explains why they can, at least in part, forecast the traders’ forecast errors and hence speculate on the market mispricing. this, in turn, crucially impacts the entrepreneurs’ incentives. because of the aforementioned speculative component, each entrepreneur bases his decision on his forecast, not only of θ, but also of ε. when it comes to forecasting θ, what distinguishes the two signals x and y is simply their precisions, πx and πy. when, instead, it comes to forecasting the noise ε, the signal y, which contains information on both θ and ε, becomes a relatively better predictor than the signal x, which only contains information on θ. this suggests that an entrepreneur who expects prices to increase with both the fundamental θ and the noise ε will find it optimal to give relatively more weight to the signal y than what he would have done in the benchmark with no information spillovers (in which p does not depend on ε). as all entrepreneurs find it optimal to do so, the impact of the noise on aggregate investment is amplified. this intuition is verified in the following proposition. proposition for any of the equilibria identified in proposition , the following is true: βx < δx, βy > δy, βθ < δθ, and βε > δε. that is, relative to the benchmark with no information spillovers, (i) individual investment responds less to the idiosyncratic signal and more to the correlated signal, and (ii) aggregate investment responds less to fundamental shocks and more to noise shocks. proposition illustrates the amplification mechanism generated by the interaction between real and financial decisions under dispersed information. in appendix b we show that this amplification mechanism is quite general, in the sense of being present in variants of our model that allow for richer information and payoff structures. however, we will also see that the more robust positive prediction is about the relative response to noise and fundamentals, rather than the absolute responses. for this reason, we henceforth define the contribution of noise to aggregate volatility as the fraction of the volatility in aggregate investment that is driven by noise, rather than by the fundamentals, and state the main positive prediction of the paper in the following form. corollary (main positive prediction) in the presence of informational spillovers, the con- tribution of noise to aggregate volatility is amplified. put it slightly differently, the mechanism identified in the paper reduces the explanatory power of the fundamentals: it reduces the r-square of a regression of aggregate investment on θ. we will discuss how this result complements our formalizations of exuberance and keynesian beauty contests in section . before proceeding to this, however, we first study certain comparative statics and the possibility of multiple equilibria. . . comparative statics and multiplicity in the absence of information spillovers, the strength of the entrepreneurs’ concern for asset prices, as measured by λ, is irrelevant for equilibrium outcomes. with information spillovers, instead, it is crucial. the next result shows how a higher λ reinforces the amplification effect of corollary . proposition as long as the equilibrium remains unique, the contribution of noise to aggregate volatility increases with λ, the strength of the entrepreneurs’ concern for asset prices. to get some intuition for this result, consider the following exercise. suppose that the initial concern for asset prices is equal to λ for all entrepreneurs and let ϕ be the associated equilibrium value for the noise-to-signal ratio in aggregate investment. now a new entrepreneur with concern λ > λ joins the economy. since this entrepreneur is infinitesimal, aggregate investment and the asset price remain unchanged. from ( ), it is easy to see that, relative to any other entrepreneur, this entrepreneur’s investment strategy will be tilted in favor of the correlated signal y. the reason is the one discussed before. relative to the idiosyncratic signal x which contains information only about θ, the correlated signal y contains information also about the common error ε. because the latter impacts the asset price, a higher concern for the latter induces the entrepreneur to respond formally, let k̂ denote the projection of equilibrium k on θ; that is, consider the regression of realized investment on realized fundamentals. since the residual k − k̂ is orthogonal to the projection k̂, we have that v ar(k) = v ar(k̂) + v ar(k − k̂). that is, aggregate volatility can the be decomposed in two components: v ar(k̂), which represents the fundamental component, and v ar(k − k̂), which represents the non-fundamental component. the contribution of noise to aggregate volatility is then defined as the fraction v ar(k − k̂)/v ar(k). in our baseline model, the residual k − k̂ depends on a single noise shock and the fraction v ar(k − k̂)/v ar(k) is simply an increasing transformation of ϕ. in the generalized model of appendix b, there are multiple noise shocks driving the residual k − k̂, but the results in corollaries and continue to hold for the fraction v ar(k − k̂)/v ar(k). more to y relative to x. next, let the concern for asset prices increase to λ for all entrepreneurs in the economy, but continue to assume that the signal z received by the financial market has a noise-to-signal ratio given by ϕ . as all entrepreneurs start responding more to the correlated signal y, aggregate investment starts responding relatively more to the noise ε. formally, this argument proves that the mapping Γ is increasing in λ for any given ϕ. next, consider what happens as the traders realize that the entrepreneurs’ incentives have changed in the aforementioned manner. because aggregate investment has become a noisier signal of the fundamentals, the traders find it optimal to respond less to it. as a result, the response of the price to θ falls, while its response to ε could either increase or fall. this last effect, once acknowledged by the entrepreneurs, can either reinforce or dampen the initial effect of the higher λ. formally, Γ(Γ(ϕ )) could be either higher or lower than Γ(ϕ ). however, as long as the equilibrium remains unique, the fixed point of Γ necessarily inherits the comparative statics of Γ, which proves the result. interestingly, however, as λ increases enough, the two-way feedback between the real and the financial sector may get sufficiently reinforced that Γ may admit multiple fixed points. different fixed points are associated with self-fulfilling prophecies regarding the quality of the signal that the real sector sends to the financial market: as the entrepreneurs respond more to the correlated signal y, they make asset prices more sensitive to noise shocks relative to fundamental shocks, which in turn justifies their stronger response to the correlated signal y. proposition there is an open set s ⊂ r such that, for all (λ,πθ,πx,πy,πω) ∈ s, there exist multiple equilibria. this multiplicity originates merely from the information spillover between the real and the financial sector of the economy. it is thus distinct from the one that emerges in coordination models of crises such as diamond and dybvig ( ) and obstfeld ( ). rather, it is closer to the one in gennotte and leland ( ) and barlevy and veronesi ( ). these papers also document multiplicity results that originate in information spillovers. however, these papers abstract from real economic activity and focus on spillovers that emerge within the financial market, between informed and uninformed traders. in our setting, instead, the multiplicity rests on the two-way feedback between the real sector and the financial market and can manifest itself as sunspot volatility in both real investment and asset prices. clearly, this possibility only reinforces the message of our paper: the mechanism we have identified can contribute to significant non-fundamental volatility, not only by amplifying the impact of correlated errors in information, but also by opening the door to additional volatility driven by sunspots. beauty contests and exuberance in the preceding analysis, we studied the economy from the perspective of rational-expectations equilibria. we now look at the problem from a different angle, one that permits us to uncover the role that higher-order uncertainty can play in our setting. this in turn helps explain the way in which our framework provides a formalization of the notions of “beauty contests” and “exuberance.” we do so in three steps. first, we show how our walrasian economy can be represented as a coordination game among the entrepreneurs; this helps us highlight certain similarities to, but also differences from, previous work that has attempted to capture keynes’ metaphor with a certain class of coordination games. second, we explain that the role of higher-order uncertainty in our setting rests on the combination of the information spillover with the option to trade; this helps clarify that our formalization of “beauty contests” is best understood as a signaling-cum-trade game between the real and the financial sector of the economy. finally, we discuss the various forms that “noise” and “exuberance” may take in our economy. . a coordination game among the entrepreneurs substituting condition ( ) into condition ( ), we can express the traders’ expectation of the funda- mentals, and therefore the equilibrium price, as a linear function of aggregate investment. replacing the resulting expression into the entrepreneurs’ optimality condition ( ) leads to the following result. proposition in any equilibrium, there exist scalars κ , κθ and α such that the equilibrium investment choices solve the following fixed-point problem: k (x,y) = e [ κ + κθθ̃ + αk(θ̃, ε̃) ∣∣∣ x,y ] , ( ) furthermore, α > if and only if high investment is “good news” about profitability (i.e., conveys a positive signal about θ), which in turn is necessarily the case whenever the equilibrium is unique. this result facilitates a certain game-theoretic representation of our economy: if we fix the equilibrium response of the financial market, the equilibrium investment decisions can be repre- sented as the perfect bayesian equilibrium of a coordination game among the entrepreneurs, with best responses given by condition ( ) and with the coefficient α measuring the degree of strategic complementarity in this game. importantly, the origin of the coordination motive is the infor- mational spillover between the real and the financial sector. although each entrepreneur alone is too small to have any impact on market prices, the entrepreneurs as a group can influence the beliefs of the traders and hence the equilibrium price. this naturally leads to a complementarity in their investment decisions: the higher the aggregate investment, the higher the traders’ expec- tation about the profitability of the new investment opportunity, and hence the higher the price at which each entrepreneur will be able to sell his capital. of course, the traders recognize this, and this in turn puts constraints on the extent that the entrepreneurs can collectively “manipulate” the traders’ beliefs. nevertheless, as the above proposition establishes, a coordination motive is present among the entrepreneurs as a long as the traders look at investment as a signal of the underlying fundamentals. this game-theoretic representation, in turn, establishes a useful parallel between our model and a class of games with incomplete information and linear best responses analyzed, among others, by morris and shin ( ) and angeletos and pavan ( , ). as it is known from this earlier work, strategic complementarity (α > ) tilts the equilibrium use of information towards correlated sources of information, which in turn offers an alternative angle on what drives the result in proposition regarding the response of individual investment to the different signals. furthermore, morris and shin ( ), and a growing body of research thereafter, have associated the aforementioned class of linear-quadratic games with keynes’ beauty contest metaphor. this approach puts aside the micro-foundations of what these games represent and instead focuses on the fact that these games help capture the dependence of equilibrium outcomes on higher-order beliefs. from this perspective, and if one treats the equilibrium response of the financial market as exogenous, our economy can be interpreted as a beauty contest among the entrepreneurs. however, it is important to note that, in contrast to this earlier work, the strategic complemen- tarity in our economy is endogenous: as already mentioned, the complementarity originates in the information spillover between the real and the financial sector, not in any direct payoff externality, production spillover, and the like. . the beauty contest game between the real and the financial sector an even more appealing—at least in our view—formalization of “beauty contests” obtains if one does not abstract from the micro-foundations and instead focuses on the endogeneity of the response of the financial market. a “beauty contest” then emerges as a game between the real and the with richer payoffs and richer market interactions, the degree of strategic complementarity α can be either positive or negative. for example, in section . we consider a variant of our baseline model that introduces a competitive labor market. in this variant, higher aggregate investment raises the demand for labor, which in turn increases equilibrium wages and reduces the expected return on capital. as a result, a source of strategic substitutability (α < ) emerges. alternatively, angeletos and la’o ( a) consider a walrasian economy in which specialization and trade of differentiated commodities introduce strategic complementarity (α > ) even in the absence of an information spillover. however, as we show in appendix b, the following is true within a rich class of environments that can accomodate the aforementioned effects: relative to a situation without information spillovers, the signaling role of aggregate investment necessarily tilts the entrepreneurs’ best responses in the direction of more strategic complementarity (or less strategic substitutability), exactly as in the baseline model considered here. in this sense, our result that the information spillover is a source of strategic complementarity is quite robust. financial sector of the economy, that is, between the entrepreneurs, as a group, and the traders, rather than as a game among the entrepreneurs. to see this more clearly, note that in our model the entrepreneurs’ payoffs depend only on θ, the exogenous return they receive if they hold on their capital, and p, the price at which they may sell their capital in the financial market. it follows that the entrepreneurs only need to forecast the fundamentals and the behavior of the traders. the traders’ behavior, in turn, is pinned down by their own beliefs about θ. this implies that the behavior of the entrepreneurs is pinned down by their first-order beliefs about θ and by their second-order beliefs about the traders’ beliefs about θ. if the traders’ beliefs about the fundamentals had been exogenous, this would have been the end of the story—beliefs of higher order would have not mattered. in contrast, higher-order beliefs do matter in our setting because the informational spillover between the real and the financial sector of the economy makes the traders’ beliefs endogenous. indeed, in order to interpret the signal conveyed by aggregate investment, the traders must form beliefs about the driving forces behind the entrepreneurs’ actions. by the argument in the preceding paragraph, the entrepreneurs’ actions are pinned down by their own first- and second-order beliefs. it follows that the traders’ beliefs about the fundamentals, and hence their behavior, depend on (i) their second-order beliefs about the entrepreneurs’ first-order beliefs about the fundamentals and (ii) their third-order beliefs about the entrepreneurs’ second-order beliefs about their own first-order beliefs. but then, in order to forecast the behavior of the traders, the entrepreneurs must form beliefs about the traders’ higher-order beliefs, and so on. these observations make clear that higher-order uncertainty plays a role in our economy only because of the information spillover from the entrepreneurs to the traders. furthermore, the pres- ence of strategic uncertainty within the group of the entrepreneurs, while empirically appealing, is not strictly needed for our mechanism. in the variant with heterogeneous priors studied in section . , we can allow the entrepreneurs to share the same information. in these respects, our formal- ization of “beauty contests” is perhaps more closely related to townsend ( ), who emphasizes the role of higher-order uncertainty in settings with endogenous learning, than to morris and shin ( ), who emphasize the role of strategic uncertainty in coordination games. . noise and exuberance the preceding discussion helps recognize the following. to facilitate the characterization of the equilibrium, we assumed a particular information structure that permitted us to guess and verify the fixed point directly instead of working with the infinite regression of higher-order beliefs. the role of higher-order uncertainty then manifested itself only in the amplification of the correlated errors in the entrepreneurs’ information about the fundamentals. however, with more general information structures, “noise” or “exuberance” could also originate from shocks to higher-order beliefs. indeed, following angeletos and la’o ( b), one could introduce shocks that move higher- order beliefs without affecting either the fundamentals or any agent’s exogenous information about the fundamentals. these shocks would then cause fluctuations in investment and asset prices that would look a lot like sunspot fluctuations, even though they would not be triggered by correlation devices and they would not rest on equilibrium multiplicity. combining these observations with the results of section , we conclude that the formalization of “exuberance” we propose in this paper can take any of the following three forms: (i) amplification of correlated errors in information about the fundamentals; (ii) fluctuations originating from shocks to higher-order beliefs; and (iii) sunspot fluctuations. either of these forms captures variation in equilibrium outcomes that likely would seem “hard to reconcile with fundamentals” in the eyes of an outside observer; they are possible in our setting because, and only because, of the information spillover between the two sectors of the economy. in section . , we discuss a fourth complementary form of “exuberance” that can obtain in a variant of our model with heterogeneous priors—this variant permits us to reinterpret the correlated error ε of our baseline model as a form of “bias” in beliefs, without, however, abandoning the axiom of rationality. finally, whereas the entire preceding discussion focuses on positive aspects, we believe that a proper formalization of “exuberance,” “sentiments,” “beauty contests,” and the like should also capture the normative aspects of these ideas. indeed, references to these notions typically come together with an argument—more or less explicit—that there is something “wrong” in the func- tioning of the economy and that the government should intervene. keynes himself brought up his famous beauty-contest metaphor, and talked more generally about “animal spirits,” as part of an explicit attempt to make a case that the market mechanism can be inefficient, not merely to describe market behavior. in this regard, the normative results of the next section are an integral part of our formalizations of “exuberance” and “beauty contests.” this is in contrast to previous work where the normative aspect is either ignored (e.g., allen, morris and shin, ; bacchetta and wincoop, ) or imposed in an ad hoc manner (e.g., morris and shin, ). efficiency and policy the analysis so far focused on the positive properties of the equilibrium. we now turn to its normative properties and to policy implications. . constrained efficiency in the environment considered in this paper, the government could obviously improve upon the competitive equilibrium if it could collect all the information dispersed in the economy and make it public—this would remove any asymmetry of information and would achieve the first-best allo- cation. in practice, it seems implausible that the government be able to perform this task. the question we address here is whether the government can improve upon the equilibrium by manip- ulating the agents’ incentives through taxes, regulation, and other policy interventions. we thus consider a notion of constrained efficiency that is designed to address this question, without getting into the details of specific policy instruments. namely, we consider a planner who can dictate to the agents how to use their available information but that cannot transfer information from one agent to another. angeletos and pavan ( , ) propose and study such a notion of constrained efficiency within a class of games with dispersed information; here, we adapt this notion to the walrasian economy under consideration by embedding the aforementioned information constraint into otherwise standard definitions of feasible and pareto-optimal allocations. definition a feasible allocation is a collection of investment choices ki, one for each entrepreneur, together with a collection of consumption choices cit, one for each entrepreneur and for each trader in each period, that jointly satisfy the following constraints: (i) resource feasibility: ∫ i∈[ , ] ci di ≤ e− ∫ i∈[ , / ] k i di,∫ i∈[ , ] ci di ≤ e,∫ i∈[ , ] ci di ≤ e + ∫ i∈[ , / ] θkidi with ci = for all i such that si = (i.e., for all entrepreneurs hit by the shock). (ii) informational feasibility: for each entrepreneur i ∈ [ , / ], ci and ki are contingent on (xi,y), ci is contingent on (xi,y,si,k,ω), and ci is contingent on (xi,y,si,k,ω,θ); for each trader i ∈ ( / , ], ci is non-contingent, ci is contingent on (k,ω), and ci is contingent on (k,ω,θ). definition an efficient allocation is a feasible allocation that is not pareto dominated by any other feasible allocation. why the government may not be able to centralize the information that is dispersed in the economy is an important and difficult question that, as emphasized by hayek, rests at the heart of the market mechanism. clearly, this question is beyond the scope of this paper. because of the linearity of preferences in consumption, efficiency leaves the distribution of consumption across periods indeterminate. moreover, the distribution of consumption across agents will depend in general on the point chosen on the pareto frontier. however, the efficient investment strategy is uniquely determined and is the one that maximizes the following welfare objective: w = e [ q̃− ∫ i k̃ i di ] where q ≡ ∫ i θkidi measures the level of aggregate output at t = and where ∫ i k̃ i di represents the social cost of producing this level of aggregate output. equivalently, w = e [ θ̃k(x̃, ỹ) − k(x̃, ỹ) ] , ( ) which leads to the following characterization of the efficient investment strategy. proposition the efficient investment strategy is given by k (x,y) = e [ θ̃|x,y ] = δ + δxx + δxy, ( ) almost all (x,y), where the coefficients δ , δx, and δy are the same as in proposition . the efficient investment strategy thus coincides with the equilibrium strategy in the benchmark with no information spillovers. it follows that our key positive result has a normative counterpart. corollary (main normative prediction) in the presence of information spillovers, the con- tribution of noise to aggregate volatility is inefficiently high. as anticipated in the previous section, this result provides the normative basis of our formaliza- tion of “exuberance” and “beauty contests.” the intuition for this result is quite simple. the agents in charge of real investment decisions possess information that permits them to forecast not only the long-run profitability of their investments but also the mispricing of this profitability by other agents at subsequent stages of financial trades. the possibility of forecasting such a mispricing in turn gives rise to a “speculative return,” which is however purely private and hence not warranted from a social viewpoint. such a private benefit tilts the way entrepreneurs respond to their sources of information away from efficiency, with negative implications for welfare. the market friction that sustains this inefficiency is only the absence of perfectly revealing markets. by this we mean the following. in walrasian settings, the absence of perfect information aggregation is tightly connected to missing markets: when markets are complete, all relevant in- formation is perfectly revealed through prices, and a first-best allocation is obtained (grossman, ). in this sense, our normative result necessarily rests on some missing market. however, this has nothing to do with borrowing constraints, incomplete risk-sharing and the like. rather, the only essential market friction is the one that limits the aggregation of information: inefficiency emerges robustly as long as the financial market looks at the real sector’s activity as a signal of the underlying fundamentals. finally, note that corollary presumes that the equilibrium is unique, which is the case we have focused on. when there are multiple equilibria, the result holds for any equilibrium in which aggregate investment increases with θ. since this property is clearly satisfied by the efficient allocation, this also means that, when there are multiple equilibria, all of them are inefficient. . policy implications while the preceding analysis suggests that there exist policies that improve upon equilibrium welfare without requiring the government to centralize the information that is dispersed in the economy, it does not spell out the details of the specific policies that permit to do so. we now show how policies aimed at reducing asset price volatility may achieve this goal. our focus on this class of policies is motivated by two considerations. first, there is a vivid debate on whether central bankers, or governments more generally, should try to tame “exuberant” movements in asset prices. second, such policies look a priori plausible in our setting, since the inefficiency in our model rests on how financial markets respond to the signals sent by the real sector. consider a proportional tax τ on financial trades at t = . this tax is meant to capture more broadly a variety of policies that may introduce a “wedge” between the asset price and the underlying private valuations of the asset; this may include not only taxes on capital gains but also regulatory interventions. for simplicity, the tax is assumed to be paid by the buyers (here the traders). to capture the idea that policy intervention may be contingent on the level of asset prices, we let the tax rate τ be contingent on p: τ = τ (p) = τ + τpp, ( ) where τ and τp are scalars chosen by the government. the equilibrium price in the financial market now satisfies p = e[θ̃|k,ω] − τ (p), which yields p = + τp ( e[θ̃|k,ω] − τ ) . ( ) for example, we could allow the entrepreneurs to trade at t = securities (“futures”) whose returns are correlated with θ; as long the price of these securities is not perfectly revealing of θ, the financial market at t = would continue to look at the equilibrium k as a signal of θ, and our results would go through. the revenues collected by this tax are rebated as a lump-sum transfer. because of linear preferences, the distribution of this lump-sum transfer is irrelevant. if the tax is procyclical, in the sense that τp > , its effect is to dampen the response of asset prices to the traders’ expectation of θ̃, and thereby to the information contained in aggregate investment. this dampens the price response to the noise ε, thereby also dampening the relative bias towards the correlated signal in the entrepreneurs’ best responses ( ). at the aggregate level, this tends to make investment less responsive to noise relatively to fundamentals. as this happens, a second, countervailing effect emerges: because entrepreneurs assign relative less weight to y, aggregate investment k becomes a more precise signal of the fundamentals θ, making prices more responsive to k and thereby also to the noise ε. however, the first effect must always dominate—for, if that were not the case, the second effect would not emerge in the first place. we infer that policies aimed at stabilizing asset prices can dampen the relative impact of noise on real economic activity. furthermore, a wide range of numerical results suggest that it is always desirable to do so to some extent, namely it is optimal to set τp ∈ ( ,∞). however, these policies reduce the impact of noise only by reducing the response of asset prices to all sources of variation in the traders’ expectations of their valuation of capital. in so doing, they also reduce the response of asset prices to the fundamentals themselves. as the real sector anticipates this, the absolute response of real economic activity to fundamentals also goes down, which entails a welfare loss, since that response was already inefficiently low. it follows that this kind of policy intervention can improve welfare, but cannot possibly restore efficiency. proposition consider the policies defined by ( ). as long as the equilibrium remains unique, a higher τp necessarily reduces the contribution of noise to aggregate volatility and, in so doing, can improve welfare. however, no policy in this class can implement the constrained-efficient allocation. the analysis above thus provides a rationale for policies aimed at reducing asset price volatility, without invoking either the presence of irrational forces among market participants or any superior wisdom on the side of the government. at the same time, it highlights an important limitation of such policies: they may tame unwanted exuberance only by also dampening the response of the economy to fundamentals. the government, however, may do better by considering more sophisticated policy interventions. by this we mean policies that are contingent on a wider set of publicly-available signals about both the exogenous fundamentals and the endogenous level of economic activity. in particular, consider a tax on capital trades whose rate is contingent, not only on the asset price p, but also on aggregate while we have not been able to prove a formal result that the optimal τp is positive, we have found this to be the case for an extensive search of the parameter space: we have randomly drawn , values of the parameter vector (λ,πθ,πx,πy,πω,λ) from ( , )×r +. for each such vector, we have numerically computed the value of τp that maximizes welfare and we have found this to be strictly positive. at the same time, we could show that a policy of full price stabilization (i.e., τp →∞) is never optimal. the equilibrium is necessarily unique if λ and τp are small enough. investment k: τ = τ (p,k) = τ + τpp + τkk, ( ) where τ ,τp,τk are scalars. by choosing τk > , the government can dampen the signaling effect of investment on asset prices and thereby ensure that asset prices no longer respond to the en- trepreneurs’ noise �. at the same time, by choosing τp < , the government can ensure that asset prices respond more strongly to all other sources of information that the traders have about the fundamentals (here summarized in the signal ω). in fact, conditioning the tax on the asset price accomplishes the same as conditioning the tax on the signal ω, and thereby on the fundamentals θ. in terms of the game-theoretic representation of proposition , this means that an appropriate combination of τk and τp permits the government to control separately α, the degree of strategic complementarity in investment decisions, and κθ, the sensitivity of best responses to (expectations of) the fundamentals. it then follows that these contingencies permit the government to reduce the relative impact of the noise while at the same time raising the absolute impact of the fundamentals, therefore restoring full efficiency. proposition consider the policies defined by ( ). these policies can control separately the response of aggregate investment to noise and fundamentals. furthermore, there exists a policy in this class that implements the constrained efficient allocation as the unique equilibrium. this result highlights the distinct role that state-contingent policies can play in controlling the decentralized use of information, and thereby the response of the economy to the underlying fundamental and noise shocks, when information is dispersed. while we illustrated this insight focusing on taxes on financial trades, its applicability is broader. for example, consider a tax on eventual capital returns (or firms’ profits). if this tax is non-contingent, then it can affect the incentives faced by the entrepreneurs and/or the traders only in a uniform way across all states of nature. in so doing, it can affect the average level of investment and the average level of the price, but cannot affect their response to the underlying shocks. in contrast, if this tax is contingent on certain public signals (e.g., the price p and aggregate investment k as of t = , or the realized aggregate output θk as of t = ), then this tax can impact incentives in a different way across different states of nature; this is because different states of nature, and different information sets, are associated with different expectations at t = regarding these contingencies. it follows that these contingencies can help control the response of the economy to the underlying fundamental and noise shocks, much alike the taxes on financial trades studied above. whether such state-contingent policies are time-consistent or politically feasible is an important question, but well beyond the scope of this paper. also, the ability of such state-contingent policies to restore full efficiency may well rest on special features of our model, such as the absence of risk aversion and the ability of the government to perfectly observe the signals that the real sector sends to financial markets. however, the (weaker) result that these we conclude this section by considering policies that directly affect the information available to the market. in particular, towards capturing the role of the government in collecting various data on economic activity at either the sectorial or the macroeconomic level, consider a variant of our model where the financial market observes only a noisy statistic of k. suppose further that the government can control the quality, or precision, of this statistic. clearly, the higher the precision of this signal, the more the weight that the traders assign to it when estimating the fundamental. it follows that the government can use the precision of this statistic to manipulate the response of asset prices to aggregate investment—essentially in the same way as it could do it with the price-stabilization policies considered above. we infer that the choice of the optimal precision is subject to essentially the same trade-offs as those emphasized for the aforementioned price-stabilization policies: increasing the precision of this statistic increases the response of real economic activity to the fundamentals, but also exacerbates the relative impact of noise. an intermediate quality of macroeconomic statistics may thus be optimal in our context, even when the cost of improving this quality is negligible. discussion and extensions in this section we discuss various extensions that help reinforce the message of the paper. we start by providing a possible reinterpretation of our results within a variant that introduces heterogeneous priors. we then continue by enriching the “real” and the “financial” side of the economy. . heterogeneous priors our analysis has imposed that all agents share a common prior. while standard in macroeconomics, this assumption may be hard to justify during the episodes of interest. rather, because of the unfamiliarity of the new investment opportunities, different agents may have different priors about their likely profitability, as well as about the informativeness of available signals (i.e., different priors about the joint distribution of the fundamentals and the available signals). we now discuss how our analysis can accommodate this possibility, while at the same time maintaining the axiom of rationality and a non-paternalistic approach to policy. contingencies can control how agents respond to their different sources of information, and in so doing control the impact of noise and fundamental shocks, is not sensitive to the details of our model. see angeletos and pavan ( ) for the broader applicability of this insight, and angeletos and la’o ( a) and lorenzoni ( ) for applications in canonical business-cycle models. in fact, it is easy to show that there is a formal equivalence between the two policies. let the statistic of aggregate investment be k′ = k + ς, where ς is gaussian noise with variance /πς. for each πς, there is a price elasticity τp of the tax in ( ) that induces the same response of the price to aggregate investment in the economy with perfect observability of k, and vice versa. it is easy to show that our results extend to a variant of our model where the entrepreneurs and the traders have different priors about θ and where these priors are common knowledge. this is because both the amplification result of corollary and the inefficiency result of corollary are driven merely by the presence of an information spillover between the two groups, which remains present irrespective of whether or not these groups share the same prior on θ. perhaps more interestingly, a complementary form of “exuberance” may emerge in our setting if we allow for heterogeneous priors about the informativeness of available signals. in particular, consider a variant where the signal y is informative of the fundamentals only in the minds of the entrepreneurs; the traders, instead, believe that y is pure noise. formally, the entrepreneurs’ prior is that y = θ + ε, while the traders’ prior is that y = ε. these differences in prior beliefs are mutually known and the rest of the model is unchanged. under this specification, y causes variation in the entrepreneurs’ beliefs that is considered “unjustified” from the traders’ perspective. however, from the entrepreneurs’ perspective, it is the traders’ refusal to believe that y contains information about θ which is “unjustified.” furthermore, these differences in opinions are mutually accepted: the agents have agreed to disagree. finally, these differences in opinions do not involve any form of naivete or irrationality: given his prior and his information, each agent forms rational expectations about the fundamentals, the prices, and the other agents’ actions; and this fact is common knowledge. because the entrepreneurs believe that y is informative about θ, they would find it optimal to react to it even if they believe that the price did not correlate with it. on the other hand, because the traders believe that y is pure noise, they would themselves not react to it if they could directly observe y. it follows that, in the absence of an information spillover, the price is uncorrelated with y while aggregate investment responds to y only in so far y impacts the entrepreneurs’ own beliefs about θ. in contrast, when the traders do not directly observe y and instead look at aggregate investment as a signal of the fundamentals, they are not able to tell apart movements in investment that are driven by signals that the traders themselves consider informative about θ (here captured by the signals x) from the movements that are driven by what the traders believe to be an unjustified “bias” in the entrepreneurs’ beliefs (here captured by the signal y). it follows that, in the presence of an information spillover, the price is correlated with y, which in turn reinforces the entrepreneurs’ incentive to respond to y. in other words, corollary continues to hold, except that the interpretation of “noise” is now different. from the eyes of the entrepreneurs, “noise” is correlated error in their own information, exactly as in the benchmark model, whereas from the eyes of the traders, “noise” is now synonymous to a “bias” in the entrepreneurs’ beliefs. this extension permits us to capture the idea that many market players often appear to be- lieve that they “know better” than the rest of the market, while at same time recognizing that other market players may also think in a symmetric way. it also brings our paper closer to the recent literature that uses heterogeneous priors to model speculative movements in asset prices (scheinkman and xiong, ) and real investment (panageas, ). nevertheless, our analysis differentiates from this literature in one crucial respect: this literature allows for heterogeneous priors but imposes symmetric information, thus ruling out the information spillover that is at the core of our analysis. in contrast, by combining heterogeneous priors with dispersed informa- tion, our approach helps uncover a novel positive result: how information spillovers may amplify the equilibrium impact of certain “biases” as some agents cannot tell apart whether the observed investment or asset price boom is driven by “hard information” or by the “biases” of other agents. furthermore, our approach has distinct normative implications. to appreciate this, recall that the concept of pareto optimality allows for subjective probabilities. it follows that heterogeneous priors, and the speculative forces studied in the aforementioned literature, do not by themselves open the door to policy intervention. rather, one has also to take a paternalistic stand that the priors of some agents are “wrong”—a stand that we have sought to avoid. in contrast, once heterogeneous priors are combined with the information spillovers we have highlighted, the con- sequent amplification of the perceived “biases” is undesirable even under the perspective of a non-paternalistic planner who evaluates each agent’s ex-ante utility using the agent’s own prior, not some other prior that he judges more appropriate. in other words, the property that agents respond to their own “biases” is not per se a symptom of inefficiency under a non-paternalistic perspective; but the property that information spillovers amplifies this response is. . richer specification of the real sector we now consider a certain variant of the real sector of our model, one that introduces a competitive labor market. the production technology uses as inputs not only capital as in the baseline model, but also labor. for tractability, this technology is assumed to be leontief, with one unit of capital requiring n units of labor at t = in order to produce θ units of the consumption good, for some n > . the net return to capital is thus r = θ−wn, where w denotes the wage rate. for simplicity, labor is supplied only by the traders. their preferences are now given by ui = ci +ci +ci −h(`i), where `i denotes labor supply and where h is a strictly convex function representing the disutility of labor. their intertemporal budget, on the other hand, is given by ci +ci +ci = e+(r−p)qi+w`i, where the last term represents labor income. it follows that we can express the payoff of a trader, up to a constant, as ui = (r −p)qi + w`i −h(`i). the payoff of a surviving entrepreneur, on the in particular, the aforementioned papers allow different agents to disagree on the informativeness of different exogenous signals about the fundamentals, but assume that all the signals are commonly observed. it follows that there is nothing to be learned from observing the behavior of other agents. allowing the entrepreneurs to also supply labor, or introducing a third class of agents (“workers”) whose only role in the economy is to supply labor would not change the results in any significant way. other hand, is ui = rki− k i , while that of an entrepreneur hit by a liquidity shock is ui = pki− k i . we characterize the equilibrium of this variant by backward induction. first, consider wages and employment (at t = ). optimality of labor supply requires that h′(`i) = w for all i ∈ [ / , ], while labor market clearing requires that ∫ i∈[ / , ] `i = nk (by the leontief assumption, the aggregate demand for labor is nk). by implication, in equilibrium, `i = ` = nk for all i ∈ [ / , ], w = h′(nk), and r = θ − h′(nk)n. it follows that the payoff of a trader can be expressed as ui = v t(θ,k,qi) −pqi, where v t(θ,k,q) ≡ [θ −h′(nk)n]q + h′(nk)nk −h(nk), while the payoff of a surviving entrepreneur can be expressed as ui = v e(θ,k,ki) − k i , where v e(θ,k,k) ≡ [θ −h′(nk)n]k. next, consider asset prices (at t = ). optimality on the traders’ side, along with the fact that q = λk in equilibrium, implies that p = et[ṽt], ( ) where vt ≡ v tq (θ,k,λk) and where et[·] denotes the traders’ expectation. finally, consider in- vestment (at t = ). substituting the price into the entrepreneurs’ optimality condition gives the following equilibrium condition: ki = ei [w̃i] + λei [ et[ṽt] − ṽt ] , ( ) where wi ≡ ( −λ)v ek (θ,k,ki) + λv t q (θ,k,λk) and where ei[·] denotes the entrepreneur’s expec- tation. these results have a simple interpretation. first, the functions v e and v t represent indirect util- ities, or the reduced-form payoffs, which emerge once equilibrium employment and wages have been solved out. the dependence of these payoffs on k reflects the pecuniary externalities associated with the labor market: higher aggregate investment raises the demand for labor, thereby raising wages and depressing the return to investment. second, the variable vt represents the marginal valuation of capital for a trader. third, the variable wi represents the marginal valuation for an entrepreneur who expects to get a price equal to vt when he sells his capital. in finance jargon, these variables represent the “fundamental valuation” of capital, or the “fundamental return” to investment. finally, the expression et[ṽt] −vt represents the pricing error in the financial market, that is, the error that the traders make in estimating their own valuation of the asset. the last term in condition ( ) then represents the entrepreneurs’ forecast of such a pricing error; this term captures a “speculative” return component akin to the one in the baseline model. as in the baseline model, the pricing error is forecastable in the eyes of the entrepreneurs only because they have private information about the sources of variation behind the signal (aggregate investment) that they collectively send to the financial market. furthermore, this speculative component is once again a zero-sum transfer between the traders and the entrepreneurs. these observations suggest that the present variant continues to feature essentially the same kind of amplification and inefficiency highlighted in the baseline model. we verify these intuitions in appendix b, where we show that corollaries and extend not only to the present variant, but also to more flexible specifications of the reduced-form payoffs v e and v t that may summarize the “inner workings” of the real sector of the economy. apart from illustrating the robustness of our insights to richer specifications of the real side of the economy, these results help clarify the notions of “fundamental” and “speculative” returns to investment. while these notions were tightly connected to the same exogenous random variable in the baseline model, here they are allowed to have deeper micro-foundations. furthermore, these results indicate how an episode of “exuberance” can be associated not only with high investment and high asset prices, but also with high employment, high wages, and an all-around economic boom. a similar reasoning then implies that the signals that the real sector sends to the financial market need not be limited to aggregate investment; they should be interpreted more broadly as the information, in part public and in part private, that the real sector conveys to financial-market participants about real economic activity. . richer specification of the financial market next, we discuss extensions that may help capture the role of the financial market as a provider of information, as opposed to a simple receiver, as in the baseline model. this possibility introduces additional feedbacks between real and financial activity, which may actually reinforce the message of our paper. to start, suppose that traders are risk averse and, instead of an exogenous public signal about θ, they observe private signals of the form ωi = θ + ηi, where ηi is noise. this would make the model of the financial market closer to the literature on rational expectations in the tradition of grossman and stiglitz ( ) and hellwig ( ). specifically, assume that the traders’ preferences display constant absolute risk aversion and that all random variables are gaussian. each trader’s demand for the asset is then given by qi = ei[θ̃] −p Γv ari[θ̃] , ( ) where ei[θ̃] ≡ e[θ̃|ωi,p,k], v ari[θ̃] ≡ v ar[θ̃|ωi,p,k] and where Γ is the coefficient of absolute risk aversion. note that the market clearing price now serves as a signal about θ, for it aggregates the information dispersed among the traders. however, as long as there are additional unobserved sources of variation in the demand or supply of the asset, the equilibrium price will not be perfectly revealing. for example, suppose the noises ηi are correlated: the price will then reveal the average ωi which is a noisy signal of θ. finally, suppose that the entrepreneurs not hit by the liquidity shock are allowed to trade in the financial market, but their valuations are subject to an additional common shock that is not observable by the traders. once again, this shock guarantees that the price does not perfectly reveal the fundamental to the traders. as long as the price is not perfectly revealing, the traders will continue to use k as a signal of θ. therefore, the key source of our information-driven complementarity would still be present in this extension. furthermore, because our mechanism reduces the informativeness of aggregate investment, it also implies that the traders end up in equilibrium with less information: the conditional uncertainty faced by each trader, v ari[θ̃], is higher. when this is the case, each trader will not only require a higher risk premium for holding the asset, but also react less to any private information she may have about θ. the equilibrium price will then also do a worse job in aggregating this information, for it will be relatively more sensitive to other sources of aggregate noise. it follows that our mechanism may also reduce the informational efficiency of the financial market. on the positive side, this means that our mechanism may raise risk premia in financial markets and amplify their non-fundamental volatility. on the normative side, the increased uncertainty may also exacerbate the misallocation of the asset, which in turn would reinforce our welfare implications: the planner would like entrepreneurs to react more to the fundamentals and less to noise, not only for the reasons emphasized in the baseline model, but also because this would transmit more precise information to the financial market and thereby improve informational and allocative efficiency. next, suppose that we introduce a second round of real investment decisions, which takes place after the financial market closes. now information would travel not only from the first round of investment to the financial market, but also from the latter to the second round of investment. this would capture the role of asset prices in guiding investment decisions by revealing valuable information that is dispersed in the marketplace and not directly available to corporate managers (e.g., dow and gorton, , subrahmanyam and titman, , chen, goldstein and jiang, ). importantly, our mechanism would then imply a deterioration in this functioning of financial markets. this is a direct implication of the argument made in the previous paragraph regarding the informational efficiency of asset prices. alternatively, suppose that we introduce a financial market before the first round of real invest- ment. this market includes some informed traders, who may or may not be present at subsequent rounds of trading, as well as some uninformed liquidity traders, whose role is to preclude perfect in- formation aggregation. suppose further that the entrepreneurs observe some private signals about whether or not the price reveals θ to the entrepreneurs is not crucial. the key is that the price does not perfectly reveal θ to the traders, so that the traders continue to use k as a signal of θ. for a full analysis of an extension along these lines, see section . of the earlier version of this paper, angeletos, lorenzoni and pavan ( ). the trading positions of the informed traders; think of this assumption as a parable for the fact that investors and firm managers are often anxious to collect information about the positions taken by some key informed big players in financial markets. then, we could re-interpret some of the exogenous signals that the entrepreneurs receive in our model as imperfect private learning about the actions of these big players. in this case, the origin of the correlation in the entrepreneurs’ signals—and thereby the initial source of “noise” or “exuberance” in our model—could well be the errors of these early traders. furthermore, because these earlier traders may themselves have some private information about the sources of variation behind the signals they send to entrepreneurs and later traders, they may also be able to forecast the errors made by these subsequent agents. an information-driven complementarity similar to the one that emerges in the entrepreneurs’ investment decisions may then emerge also in the traders’ positions. this complementarity, in turn, is likely to be stronger the higher the degree of short-termism of the traders: the more the early traders’ portfolio choices are driven by forecasts of future pricing errors, as opposed to forecasts of the fundamentals, the stronger the complementarity in their choices, much alike what happens in the case of the entrepreneurs in our model. an extension along these lines could thus not only reinforce our results, but also bring our analysis closer to froot, scharfstein, and stein ( ), allen, morris and shin ( ), and other papers that study the implications of short-termism in financial markets. conclusion this paper examined the interaction between the real and the financial sector of a neoclassical economy with dispersed information about the profitability of a new investment opportunity. by conveying a positive signal about profitability, higher aggregate investment—or, more broadly, higher real activity—increases asset prices, which in turn raises the incentives to invest. this two- way feedback between real and financial activity makes real economic decisions sensitive to higher- order expectations and amplifies the impact of noise on equilibrium outcomes. as a result, economic agents may behave as if they were engaged in a keynesian “beauty contest” and the economy may exhibit fluctuations that may appear in the eyes of an external observer as if they were the product for the sake of this discussion, ignore the additional effects that may obtain when these big players attempt to manipulate asset prices and/or real economic activity. indeed, suppose that the entrepreneurs, in addition to the market-clearing price in the first round of trading, observe two purely idiosyncratic signals, one about the fundamentals θ and one about the position q of the early informed traders. let these signals be xi = θ + ξi and yi = q + ςi and impose that the noises ξi and ςi are independent across i and of any other random variable. next, suppose that the equilibrium value of q is a linear function of the early traders’ average forecast of θ, which in turn is a linear function of θ itself and some noise ε: q = ψ + ψ θ + ψ ε. the observation of the signal yi is then informational equivalent to the observation of the signal xi ≡ ψ (yi − ψ ) = θ + ψ ψ ε + ψ ςi. clearly, this is a private signal about θ, whose error is correlated across the entrepreneurs. a mechanism similar to the one in the baseline model is therefore once again at play. of “irrational exuberance.” importantly, these effects are symptoms of inefficiency, are driven purely by the dispersion of information, and obtain in an otherwise conventional, neoclassical, setting. while both irrationality and our mechanism can justify policy intervention, our approach does not rest on any presumption of superior wisdom on the government’s side. we showed how stabiliza- tion policies that are contingent only on publicly-available signals about the exogenous fundamen- tals and the endogenous economic activity can indirectly tax/subsidize the response of economic agents to different sources of information. through a proper design of such contingencies, the gov- ernment can dampen the impact of noise on equilibrium outcomes, improve welfare, and, in certain cases, even attain a certain constrained-efficiency target. the effects analyzed in this paper are likely to be stronger during periods of intense techno- logical or institutional change, when the information about the profitability of new investment opportunities is likely to be highly dispersed. at some level, this seems consistent with the recent experiences surrounding the internet revolution or the explosion of investment opportunities in emerging economies. our mechanism may, however, also be relevant for ordinary cyclical fluctua- tions. indeed, information regarding aggregate supply and demand conditions seems to be widely dispersed, as indicated by surveys of forecasts and by the financial markets’ anxiety preceding the release of key macroeconomic statistics. this opens the door to the possibility that effects similar to the ones documented in this paper may operate over the business cycle. finally, our analysis has left aside credit market frictions that make the availability of outside finance relevant for investment decisions. we have done so in order to focus on the informational spillover as the only source of amplification and inefficiency. however, the episodes of interest appear to involve important interactions between credit markets, asset prices, and investment. an extension of our model that introduces collateral constraints as in kiyotaki and moore ( ) may reveal additional amplification effects coming from the interaction of our mechanism with a credit multiplier. episodes of “exuberance” may then manifest, not only in exuberant investment and asset prices, but also in exuberant credit booms. appendix a: proofs proof of proposition . the proof proceeds in three steps. step fills in the details of the equilibrium characterization in the main text. step analyzes the fixed point problem and proves existence of a equilibrium with βx,βy,βθ,βε,γθ,γε,γη > . step proves uniqueness of the equilibrium for λ small enough. step . first note that there exist no equilibria in which βθ = . indeed, in any such equilibrium, k would convey no information to the financial market. the equilibrium price would then simply be equal to e[θ̃|ω]. because this is an increasing function of θ, the entrepreneurs’ best responses would then impose that they react positively to both signals, thus contradicting the assumption that βθ = . next, note that there exists no equilibrium in which βε = . indeed, in any such equilibrium, k would perfectly reveal θ to the traders in which case the equilibrium price would be equal to θ. but then again each entrepreneur would find it optimal to follow a linear strategy that responds positively to both x and y, contradicting the assumption that βε = . hence, any equilibrium must satisfy βθ = βx + βy = and βε = βy = . from the analysis in the main text, we then have that in any equilibrium the price is given by ( ) and the entrepreneurs’ investment strategy is given by ( ). substituting ( ) into ( ), and using the facts that πz = πy/ϕ , e[θ̃|x,y] = µ + δx (x−µ) + δy (y −µ), e[ε̃|x,y] = y − e[θ̃|x,y], and e[η̃|x,y] = , we have that the entrepreneurs’ investment strategy is given by k (x,y) = β + βxx + βyy, where the coefficients (β ,βx,βy) are given by the following: β = ( −βx −βy) µ ( ) βx = ( −λϕ πy + ϕπθ πy + ϕ (πθ + πω) ) δx ( ) βy = ( + λϕ πx + ( −ϕ) πθ πy + ϕ (πθ + πω) ) δy ( ) any equilibrium must thus satisfy ( )-( ), along with ϕ = βy βx + βy . step . to establish existence of a equilibrium in which βx,βy > , let b ≡ βy/βx. dividing ( ) by ( ) and noting that ϕ = b/( + b) yields b = πy + ( b +b ) (πθ + πω) + λ b +b ( πx + +bπθ ) πy + ( b +b ) (πθ + πω) −λ b +b ( πy + b +bπθ ) δy δx . ( ) using the definitions of δx, and δy, as in proposition one can then show that the right-hand side of ( ) is equivalent to the following function of b: f (b) ≡ δy δx { + λ ( + b) b [( −λ) ( −δx) + Ω]b + ( −λ) δyb + δy } ( ) where Ω ≡ πω πx+πy+πθ > . noting that b is a monotone transformation of ϕ, we have that the mapping b′ = f(b) identifies the mapping ϕ′ = Γ(ϕ) mentioned in the main text. it is easy to see that f is well defined and continuous over r+, with f (δy/δx) > δy/δx and limb→+∞f (b) finite. it follows that f has at least one fixed point b > δy/δx. given this value of b, existence of a equilibrium can be established by construction. first, the equilibrium value of βy is obtained substituting ϕ = b/ ( + b) into ( ) and is clearly positive. next, the equilibrium value of βx is given by βy/b and is also positive. given βx and βy, the equilibrium value of β is given by ( ). finally, from the fact that βθ = βx + βy and βε = βy, and from the formulas for γθ, γε and γη in the main text, it is immediate to see that all these coefficients are also positive. step . to prove uniqueness, first notice that there exist no equilibria in which βx = . this can be seen directly from ( ). this in turn implies that all equilibria, irrespective of the sign of βx and βy, must correspond to a fixed point of the function f defined in ( ). next, note there exists λ′ > such that, for any λ ∈ [ ,λ′] the denominator in the fraction in the right-hand side of ( ) is strictly positive, for any b ∈ r. this implies that, when λ ∈ [ ,λ′], the function f is defined and continuously differentiable over the entire real line, with f ′ (b) = λ δy δx [δy − ( −λ) ( −δx −δy) − Ω] b + δyb + δy {[( −λ) ( −δx) + Ω]b + ( −λ) δyb + δy} moreover, lim b→−∞ f(b) = lim b→+∞ f(b) = f∞ ≡ δy δx [ + λ ( −λ) ( −δx) + Ω ] > δy δx . thus, from now one, restrict attention to λ < λ′. we now need to consider two cases. first, suppose δy = ( −λ) ( −δx) + Ω. the function f then has a global minimum at b = − / . in this case, f is bounded from below and above, respectively, by f ≡ f(− / ) and f ≡ f∞. second, suppose δy = ( −λ) ( − δx) + Ω. then f ′ (b) has two zeros, respectively at b = b and at b = b , where b ≡ −δy − √ [( −λ)( −δx −δy) + Ω]δy δy − ( −λ) ( −δx −δy) − Ω and b ≡ −δy + √ [( −λ)( −δx −δy) + Ω]δy δy − ( −λ) ( −δx −δy) − Ω . when δy = ( −λ) δ + Ω, the function f then has a global minimum at f ≡ f (b ) and a global maximum at f ≡ f (b ). it is easy to check that in all the cases considered both f and f converge to δy/δx as λ → . but then f converges uniformly to δy/δx as λ → . it follows that for any ε > , there exists a λ̂ ≤ λ′ so that, whenever λ < λ̂, f has no fixed point outside the interval [δy/δx −ε,δy/δx + ε]. now, with a slight abuse of notation, replace f (b) with f (b; λ), to highlight the dependence of f on λ. notice that ∂f(b; λ)/∂b is continuous in b at (b; λ) = (δy/δx, ) and ∂f(δy/δx; )/∂b = . it follows that there exist ε̃ > and λ̃ ∈ ( , λ̂] such that ∂f(b; λ)/∂b < for all b ∈ [δy/δx−ε̃,δy/δx+ε̃] and λ ∈ [ , λ̃]. combining these results with the continuity of f(·; λ), we have that there exist ε̄ > and λ̄ > such that, for all λ ∈ [ , λ̄], the following are true: for any b /∈ [δy/δx − ε̄,δy/δx + ε̄], f (b; λ) = b; for b ∈ [δy/δx−ε̄,δy/δx +ε̄], f is continuous and differentiable in b, with ∂f(b; λ)/∂b < . it follows that, if λ ≤ λ̄, f has at most one fixed point, which establishes the result. proof of proposition . in any of the equilibria identified in proposition , we have that ϕ ∈ ( , ). from conditions ( ) and ( ) in the proof of that proposition, it then follows that βx < δx and βy > δy. moreover, the two inequalities imply ϕ −ϕ = βy βx > δy δx = πy πx . ( ) finally, βθ ≡ βx + βy = δx + δy + λ ϕπy πθ + πx + πy πx + ( −ϕ) πθ πy + ϕ (πθ + πω) −λ ϕπx πθ + πx + πy πy + ϕπθ πy + ϕ (πθ + πω) = δx + δy + λ ϕπθ πθ + πx + πy ( −ϕ) πy −ϕπx πy + ϕ (πθ + πω) < δx + δy where the last inequality follows from ( ). proof of proposition . consider the function f (b; λ) introduced in the proof of proposition . for any λ ∈ [ , λ̄), the function f (·; λ) is continuously differentiable over r. take any pair λ′,λ′′ ∈ [ , λ̄) with λ′′ > λ′, and let b′ and b′′ be the unique solutions to f (b; λ) = b, respectively for λ = λ′ and λ = λ′′ (existence and uniqueness of such solutions follows directly from proposition ). furthermore, as shown in the proof of proposition , f (b,λ′) − b > for all b ∈ [ ,b′). simple algebra then shows that ∂f (b; λ) /∂λ ≥ for any b ≥ , with strict inequality if b > . it follows that b′′ > b′. the result in the proposition then follows from the fact that ϕ ≡ b/( + b) and the fact that the contribution of noise to aggregate volatility is an increasing function of ϕ. proof of proposition . consider the function f (b; λ,δx,δy, Ω) introduced in the proof of proposition ; for convenience we are highlighting here the dependence on all parameters, with Ω ≡ πω πx+πy+πθ . take the parameters (λ,δx,δy, Ω) = (. , . , . , . ). with these parameters the function f is defined and continuous over the entire real line and b and limb→−∞f (b; λ,δx,δy, Ω) > > −∞, ensure that, in addition to a fixed point in (δy/δx, +∞), f admits at least one fixed point in (−∞,b ) and one in (b , ). furthermore, each of these three fixed point is “strict” in the sense that f (b) − b changes sign around them. because f is continuous in (b; λ,δx,δy, Ω) in an open neighborhood of (λ,δx,δy, Ω) = (. , . , . , . ) , there necessarily exists an open set b ⊂ ( , ) × r such that f admits at least three fixed points whenever (λ,δx,δy, Ω) ∈ b. the result in the proposition then follows by noting that for any (λ,δx,δy, Ω) ∈ b, there corresponds a unique set of parameters (λ,πθ,πx,πy,πω) ∈ r . proof of proposition . substituting condition ( ) into condition ( ) gives the equilibrium price as a linear function of aggregate investment and the traders’ exogenous signal: p(θ,ε,η) = γ + γkk(θ,ε) + γωω, ( ) with γ ≡ πθµ−πzβ /βθ πθ+πω+πz , γk ≡ πz/βθ πθ+πω+πz , and γω ≡ πωπθ+πω+πz . clearly, γk > if and only if βθ > , which means that high investment is a positive signal about θ. the result then follows from substituting ( ) into the entrepreneurs’ optimality condition ( ) and letting κ ≡ λγ , κθ ≡ −λ + λγω and α ≡ λγk. proof of proposition . this follows directly from the main text. proof of proposition . consider the first claim, namely that a high τp reduces the relative contribution of noise. substituting the price ( ) into the entrepreneurs’ best response ( ) and using ( ), one obtains a system of equations for β , βx and βy, as in the proof of proposition . following similar steps as in the proof of that proposition, it is possible to show that a equilibrium is characterized by a ratio b = βy/βx that satisfies b = f (b; Ψ) where f (b; Ψ) ≡ δy δx [ + b ( + b) λΨ (( −λ) (δ + δy + Ω) + λΩΨ) b + ( ( −λ) + λΨ) δyb + ( −λ + λΨ) δy ] with Ψ ≡ / ( + τp). following steps similar to those in the proof of proposition , one can then easily see that (i) there always exists a solution to f (b; Ψ) = b with b > δy/δx and (ii) that, starting from such a solution, one can construct a equilibrium in which βx,βy > . furthermore, for any b > , f (b; ·) is increasing in Ψ. we thus conclude that, as long as the equilibrium is unique, the equilibrium value of b is increasing in Ψ. equivalently, the ratio ϕ = βε βθ+βε , and hence the relative contribution of noise to aggregate activity, is decreasing in τp lastly, following steps similar to those in the proof of proposition , one can also verify that the equilibrium is indeed unique when λ and τp are small enough. next, the claim that a positive τp may increase welfare can be established by numerical example; see footnote . finally, consider the last claim, namely that there is no policy as in ( ) that can implement the constrained efficient allocation as an equilibrium. towards delivering a contradiction, suppose that the opposite is true. comparing the entrepreneurs’ equilibrium best responses ( ) with the efficiency condition ( ), one can immediately see that efficiency requires that the following condition holds: e [ p̃− θ̃ ∣∣∣x,y] = for all x,y. substituting the equilibrium price ( ), this condition can be rewritten as e [ + τp ( e[θ̃|k̃, ω̃] − τ ) − θ̃ ∣∣∣∣x,y ] = for all x,y. ( ) by proposition , the fact that the policy implements the efficient allocation in turn implies that k = δ +δθθ+δεε. this implies that e[θ̃|k,ω] = γ +γkk +γωω where the coefficients (γ ,γk,γω) are as in section with β = δ , βx = δx, and βy = δy. therefore, ( ) can be rewritten as e [ + τp [ γ + γk ( δ + δθθ̃ + δεε̃ ) + γωω̃ − τ ] − θ̃|x,y ] = . taking unconditional expectations, one can then see that τ and τp must satisfy + τp [γ + γk (δ + δθµ) + γωµ− τ ] −µ = . subtracting side by side the last two equations, after some manipulation, one obtains that[ + τp (γkδθ + γω) − ] e [ θ̃ −µ|x,y ] + + τp γkδεe [ε̃|x,y] = . substituting for the terms in expectation yields[ + τp (γkδθ + γω) − ] [δx(x−µ) + δy(y −µ)] + + τp γkδε [y −µ−δx(x−µ) −δy(y −µ)] = for all x,y. given that this condition must hold for all x and y, it must be that + τp (γkδθ + γω) − − + τp γkδε = , ( )[ + τp (γkδθ + γω) − ] δy + + τp γkδε ( −δy) = . substituting the first condition into the second gives + τp γkδε = . this last condition cannot be true given that, when investment is efficient, γk is necessarily positive, and given that δε > and τp must be finite to ensure that ( ) is satisfied. therefore, there is a contradiction. we conclude that a simple stabilization policy as then one given in ( ) cannot implement the constrained efficient allocation as a competitive equilibrium. proof of proposition . to establish the result, it suffices to show that there exists a policy of the type given in ( ) such that, under this policy, there exists a competitive equilibrium in which e[p̃− θ̃|x,y] = for all x,y. ( ) to see that this is indeed the case, note that, under any policy as in ( ), the equilibrium price must satisfy p = e[θ̃|k,ω] − τ − τpp− τkk. equivalently, p = + τp [ e[θ̃|k,ω] − τ − τkk ] . ( ) next note that if the policy (τ ,τp,τk) implements the constrained efficient allocation, then e[θ̃|k,ω] = γ + γkk + γωω ( ) with coefficients (γ ,γk,γω) as in section with β = δ , βx = δx, and βy = δy. replacing ( ) into ( ), one can then easily see that the policy with coefficients τ = γ , τk = γk, τp = γω − . is such that p− θ = ω − θ = η. since the entrepreneurs possess no information on the shock η at time , we then have that e [η̃|x,y] = which verifies that, under the identified policy, condition ( ) is satisfied. finally, note that τk > and τp < ; this last result follows from the definition of γω, which implies that γω ∈ ( , ). appendix b: a generalized model this appendix considers a generalization of our model that helps illustrate the robustness of our key positive and normative results (as stated in corollaries and ) and also forms the basis for some of the related claims made in the main text. information structure. suppose that the entrepreneurs observe s > signals about θ. index these signals by s ∈ { , ...,s} and write them as xis = θ + ξis, where ξis is the error in the s-th signal observed by entrepreneur i. let ρs ≡ corr(ξis,ξjs), for i = j, denote the correlation in the s-th signal. finally, let ei[·] denote the expectation conditional on the information available to entrepreneur i, i.e., given the signals xi ≡ (xi , ...,xis). payoff structure. for a surviving entrepreneur, the value of holding k units of capital in period is v e(θ,k,k). an entrepreneur’s payoff is then v e(θ,k,k)−k / if he is not hit by a liquidity shock, and pk−k / otherwise. for a trader, on the other hand, the value of holding q units of capital is v t(θ,k,q), so that his payoff is v t(θ,k,q)−pq. the functions v e and v t are meant to capture the reduced-form payoffs that the agents may obtain through a variety of market interactions outside the focus of our analysis. for example, in the variant considered in section . , these payoffs summarize the interaction of the agents in a competitive labor market during the production stage. to maintain tractability, we impose that these functions a linear-quadratic. to guarantee that individual decision problems are concave, we further impose that v ekk ≤ and v t qq ≤ . we also let v ekθ > and v t qθ > , so that higher θ is interpreted as better fundamentals. finally, we assume that ( −λ)v ek(θ,k,k) + v t k(θ,k,q) = ( ) where q = λk. this assumption is motivated by the following considerations. the external effects featured in the reduced-form payoffs v e and v t are meant to capture only the pecuniary externalities that emerge in certain market interactions, like in the case of the labor market in section . . in walrasian settings, such pecuniary externalities need not be the source of any inefficiency: they often wash out at the aggregate. we impose ( ) only in order to capture this idea, and thereby to isolate the information spillover as the only source of inefficiency. equilibrium and efficiency. the following proposition provides a characterization of the equi- librium and efficient allocations for the more general model described above. proposition (i) for any equilibrium, there exist scalars κ , κθ, and α (these scalars depend on the payoff structure, the information structure, and the particular equilibrium) such that investment satisfies the following: ki = ei[κ + κθθ̃ + αk̃]. ( ) (ii) there exists scalars κ∗ , κ ∗ θ, and α ∗ (these scalars depend only on the payoff structure) such that, in the unique constrained efficient allocation, investment satisfies the following: ki = ei[κ∗ + κ ∗ θθ̃ + α ∗k̃]. ( ) (iii) the relative contribution of noise to aggregate volatility is higher in equilibrium than in the constrained-efficient allocation if and only if α > α∗. (iv) there exists a constant ψ > such that, for any equilibrium, α = α∗ + ψλ ∂et[θ̃] ∂k . ( ) by implication, α > α∗ if and only if high investment serves as a positive signal about θ. (v) the equilibrium is constrained efficient if and only if there are no information spillovers. parts (i) and (ii) provide a certain isomorphism between the generalized economy of this ap- pendix and the class of games studied in angeletos and pavan ( , ). the scalar α can then interpreted as the degree of complementarity featured in any given equilibrium, while α∗ can be interpreted as the degree of complementarity featured in the efficiency allocation. part (iii) points out that comparing the relative impact of noise in any equilibrium with that in the efficient allocation is synonymous to comparing α with α∗. part (iv) then establishes that the only source of discrepancy between α with α∗ is the information spillover, while part (v) points out that the equilibrium is efficient when and only when the information spillover vanishes. the combination of these results then imply that the key positive and normative results of the baseline model, as stated in corollaries and , continue to hold in the more general model consider here: as long as high investment is “good news” about the underlying fundamentals, the relative impact of noise on equilibrium investment is both higher than what it would have been in the absence of information spillovers (amplification) and excessive from a social perspective (inefficiency). proof of proposition . part (i). clearly, the equilibrium price must satisfy p = et[v tq (θ̃,k,λk)] where et denotes the traders’ expectation, given their available information. by implication, the equilibrium level of investment must satisfy ki = ei[w(θ̃,k̃,ki)] + λei [ et[v tq (θ̃,k̃,λk̃)] −v t q (θ̃,k̃,λk̃) ] , ( ) where ei denotes the expectation of entrepreneur i and where w(θ,k,k) ≡ ( −λ)v ek (θ,k,k) + λv t q (θ,k,λk). note that this condition must hold irrespective of whether there are information spillovers from the real sector to the financial market; in fact, this condition holds for any information structure. because the functions v e and v t are both linear-quadratic, the function w is itself linear: w(θ,k,k) = w + wθθ + wkk + wkk, ( ) where w ,wθ,wk,wk are scalars pinned down by the payoff structure, with wθ ≡ ( −λ)v ekθ +λv t qθ > and wk ≡ v ekk ≤ . next, because k is known to the traders, and because the function v t q is linear, we have that the traders’ error in forecasting their valuations is proportional to their error in forecasting θ: et[v tq (θ̃,k,λk)] −v t q (θ,k,λk) = v t qθ · ( et[θ̃] −θ ) ( ) substituting ( ) and ( ) into ( ), we have that, in equilibrium, the investment strategy must satisfy ki = ei [ w −wk + wθ −wk θ̃ + wk −wk k̃ + λψ ( et[θ̃] − θ̃ )] ( ) where ψ ≡ v tqθ −wk > . next, note that, in any equilibrium, the entrepreneurs’ investment strategy is given by ki = β + s∑ s= βsxi,s for some scalars β ,β , ...,βs. by implication, aggregate investment is given by k = β + βθ(θ + ε) where βθ ≡ ∑s s= βs and where ε ≡ ∑s s= βs βθ εs is a weighted average of the correlated errors in the entrepreneurs’ signals. it follows that, in the eyes of the traders, k is a gaussian signal of θ, which in turn implies that their forecast of θ can be written as follows: et[θ̃] ≡ e[θ̃|ω,k] = γ + γωω + γkk ( ) where ω is the exogenous information of the traders and where γ ,γω,γk are scalars, with γk > if and only if βθ > . next, note that, since the entrepreneurs have no information about the error in the traders’ exogenous signal ω, their forecast of ω̃ coincides with their forecast of θ̃: ei[ω̃] = ei[θ̃]. substituting ( ) into ( ) and using ei[ω̃] = ei[θ̃], we conclude that the investment strategy must indeed satisfy condition ( ), with the scalars κ , κθ and α defined as follows: κ ≡ w −wk + λψγ , κθ ≡ wθ −wk + λψ(γω − ), and α ≡ wk −wk + λψγk ( ) part (ii). consider the constrained efficient allocation. first, note that, irrespective of the information structure and irrespective of the investment strategy at t = , the planner always finds it optimal to allocate the supply of capital λk at t = uniformly across the traders: qi = λk for all i ∈ ( / , ]. this is a direct implication of the concavity of payoffs with respect to q. it follows that the welfare objective is given by w = e [ − k̃ + ( −λ)v e(θ̃,k̃, k̃) + v t(θ̃,k̃,λk̃) ] clearly, this is the same as welfare in a variant economy where there is only one class of agents, say the entrepreneurs, whose payoffs are given by u = − k + ( −λ)v e(θ,k,k) + v t(θ,k,λk) this variant economy is nested in the class of economies studied in angeletos and pavan ( , ). following similar steps as in the proof of proposition in angeletos and pavan ( ), it is easy to check that the constrained efficient allocation is pinned down by the following condition: ei [ uk(θ̃,k̃,ki) + uk(θ̃,k̃,k̃) ] = using the definition of u in our setting, the above can be rewritten as follows: ei [ −ki + ( −λ)v ek (θ̃,k̃,ki) + ( −λ)v e k(θ̃,k̃,k̃) + v t k(θ̃,k̃,λk̃) + λv e q (θ̃,k̃,λk̃) ] = or, equivalently, ki = ei [ w(θ̃,k̃,ki) + ( −λ)v ek(θ̃,k̃,k̃) + v t k(θ̃,k̃,λk̃) ] under the assumption introduced in ( ), the above reduces to ki = ei[w(θ̃,k̃,ki)]. ( ) using ( ), we conclude that the efficient investment must indeed satisfy ( ), with the scalars κ∗ , κ∗θ and α ∗ defined as follows: κ∗ ≡ w −wk , κ∗θ ≡ wθ −wk , and α∗ ≡ wk −wk . ( ) finally, existence and uniqueness of the fixed point to condition ( ) follows from essentially the same arguments as in the proof of proposition of angeletos and pavan ( ). part (iii). the preceding parts imply that the equilibrium and efficient allocations of our economy can be understood as the equilibrium and efficient allocations of the class of games studied in angeletos and pavan ( ). part (iii) then follows from proposition of that paper. part (iv). this part follows directly from the definition of α in ( ) and α∗ in ( ), along with the observation that, in any given equilibrium, γk gives the slope of et[θ̃] with respect to k and γk > if and only if βθ > . part (v). consider the case with no information spillovers, which is nested by letting the in- formation ω that the traders possess be a sufficient statistics for the entire information that the entrepreneurs collectively possess. in this case, et[θ̃|ω,k] = et[θ̃|ω] and ei[et[θ̃] − θ̃] = , irre- spective of the investment strategy. from ( ), one can then immediately see that the equilibrium allocation coincides with the constrained efficient allocation and, by implication, is also unique. conversely, consider the case with information spillovers. that the efficient allocation cannot be an equilibrium follows directly from part (v) along with the fact that investment is a positive signal of θ along the efficient allocation. references [ ] abel, andrew b., and olivier j. blanchard ( ), “the present value of profits and cyclical movements in investment,” econometrica , - . 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[ ] vives, xavier ( ), information and learning in markets, princeton university press. u n i v e r s i t y o f c o p e n h a g e n beauty and bacteria visualizations in molecular ecology sommerlund, julie published in: configurations publication date: citation for published version (apa): sommerlund, j. ( ). beauty and bacteria: visualizations in molecular ecology. configurations, ( ), - . download date: . apr.. https://curis.ku.dk/portal/da/publications/beauty-and-bacteria(a f - - c - - eb aa bbb).html beauty and bacteria: visualizations in molecular microbial ecology sommerlund, julie. configurations, volume , number , fall , pp. - (article) published by the johns hopkins university press doi: . /con. . for additional information about this article access provided by new copenhagen university library at / / : pm gmt http://muse.jhu.edu/journals/con/summary/v / . sommerlund.html http://muse.jhu.edu/journals/con/summary/v / . sommerlund.html . biofilms are communities of bacteria—often comprising different species—that lump together on a surface and protect themselves with a layer of slime. biofilms can be found anywhere—in water pipes, on teeth, in refrigerators—but only recently did researchers start creating and studying them in laboratories. previously, scientists worked primarily with one species of bacterium at a time, which they suspended in wa- ter. today there is a growing awareness that this is not how bacteria exist in nature— where they most commonly live in biofilms. for further discussion of the challenges that arise from biofilm research, which is by definition transdisciplinary, combining ecological methods with techniques from molecular biology, see julie sommerlund, “multiple classifications and research practices: classifications in molecular microbial ecology,” social studies of science (forthcoming). introduction in november , nature, the prestigious scientific periodical, ran a news feature entitled “slimebusters.” the feature dealt with biofilm, and was illustrated by a picture of biofilm made by a group of microbiologists working with confocal scanning laser micro- scopes (cslm) at the danish technical university (fig. ). having a picture published in nature was somewhat of an event for these re- searchers. at the time, i was doing observational studies in the group, and the researchers told me that this would probably be the only time that anything they produced would be published in na- ture. they joked about it–that their only publication in nature was a picture illustrating an article called “slimebusters,” and not a “real” scientific article. i did not understand what was “not really scien- tific” about it. i asked the professor in the group what the problem was, and he replied that the pictures they made had become “too configurations, , : – © by the johns hopkins university press and the society for literature, science, and the arts. beauty and bacteria : visualizations in molecular microbial ecology julie sommerlund the danish school of design configurations artistic”; the group had even been approached by an experimental jazz-saxophonist, who wanted to use the pictures as a visual back- ground at a concert. not that it matters as such, the professor said, but the group is becoming famous for the aesthetic qualities of its pictures, not for its contribution to “hard science.” interesting di- chotomy, i thought. in this paper, i intend to pursue the assumed dichotomy between science and aesthetics. one of the most remarkable features of the boundary between the two is that these researchers seem to disre- gard it in practice and to mix science and aesthetics in a quite radi- cal way, while their verbal reflections of their practice seldom recog- nize this. in other words, there seems to be a major discrepancy between what the researchers say and what they do. in the follow- ing, i will trace the discourses and practices of science and aesthetics by analyzing the making of the group’s emblematic photographs, the cslm-images. in the first part of the paper, i will examine how bacteria in biofilms are modified in a fashion that makes them visi- ble; in the second part, i will analyze how the pictures are edited and made understandable. science, art, and aesthetics like the stated aim of alberto cambrosio, daniel jacobi, and pe- ter keating, my aim with this paper is to “contribute to the analysis of “nonart” (in the present case scientific) images.” the critical dif- ference between art and nonart is arguably that aesthetics is an ex- plicit actor in the construction of art, whereas aesthetics plays only an implicit, or even hidden, role in the construction of science. in the following, i will discuss the relations between these three phe- nomena: science, art, and aesthetics. traditionally, science is perceived as focusing solely on content while being completely oblivious to form, whereas aesthetics is per- ceived as concentrating exclusively on form and disregarding con- tent. this division is so crude that it borders on caricature, and many scholars have written about the complexity of the relation between content and form. here, however, i will stay with the more “tradi- . alberto cambrosio, daniel jacobi, and peter keating, “arguing with images: paul- ing’s theory of antibody formation,” representations ( ): –- , on p. . . prominent among these is hayden white, the content of the form (baltimore/lon- don: johns hopkins university press, ). the form analyzed is the narrative, and not visual imagery as in this paper; however, the point in this case—that content and form cannot be regarded as discrete parts, but rather are intimately intertwined—goes for the present study as well. tional” stance on content and form for a while, because this is the stance that i have met in the laboratory when the researchers com- mented on their work, and therefore it will have a profound impact on the analyses that follow. important consequences of the traditional view of content and form—that they are different, and that aesthetic concerns have no place in science—are the divergent ways of regarding the constructive processes leading to the end product, be it scientific or aesthetic: aesthetics generally highlights the processes leading to the final product. skill and technique are often major elements of the work, and are experienced as pleasurable to the viewer/listener/receiver. thus, appreciating the violinist’s ability to move her fingers rapidly and precisely is as vital a part of the experience when listening to pa- ganini as is the music “in itself”. appreciation of the painter’s ability to apply paint to canvas and his ingenuity in coming up with new ways of doing so is as important a part of the experience when look- ing at a van gogh painting as are the colors and shapes “in them- selves.” knowing that bach composed das wohltemperierte klavier sommerlund / beauty and bacteria figure . christensen, haagensen, heydorn & molin, biofilm consisting of acinetobacter and p. putida (courtesy of applied and environmental microbiology and the authors, re- published from “metabolic commensalism and competition in a two-species microbial consortium,” may , vol. , no. . p. – ) around the twenty-four scales, presenting a prelude and a fugue in each, adds grandeur and overarching structure to the music “in itself.” in science, however, the underlying processes behind the inven- tion of scientific facts and data presented in publications are rou- tinely suppressed. working hypotheses are left unmentioned, failed experiments likewise, and—as we shall see—data are presented in styles that suppress the author as an individual and replace him or her by an impersonal, all-knowing author as anchor of the text. thus, in science, the constructive processes deduct validity and weight from the end product; in aesthetics, the constructive processes add to the experience of the end product. the picture in nature points directly to this dichotomy: if science is investigation of content, and aesthetics is invention of form, then the constructive aspects of the pictures’ aesthetic qualities challenge their scientific status. the issue of science and aesthetics is central to a growing de- bate within science studies that focuses on visualizations in science. examples are the anthologies representation in scientific practice and picturing science, producing art, as well as a number of recent articles. among the writers participating in this debate, bruno latour is probably one of the most influential, in regard to both the scientific community in general and this paper in particular. latour has writ- ten extensively about science, and has also touched upon the topics of aesthetics, construction processes, and inscription devices, which are all important to this paper. in an article entitled “how to be iconophilic in science, art and religion,” he comments directly on the science/aesthetics debate. he claims that matters of construc- tion lie at the very core of art, which is in agreement with the points i made above. art history, which explains how specific works of art configurations . it is a common point within science studies that the sciences become sciences, aloof from other epistemological enterprises, by erasing the traces of work and contin- gency that have led to the data presented. see, e.g., bruno latour, “how to be iconophilic in science, art and religion,” in picturing science, producing art, ed. caro- line a. jones and peter galison, (london.new york: routledge, ), pp. – . . michael lynch and steve woolgar, eds., representation in scientific practice (cam- bridge, mass.: mit press, ). . jones and galison, picturing science, producing art (above, n. ). . see, e.g., bruno latour and steve woolgar, laboratory life (princeton: princeton uni- versity press, ); bruno latour, science in action (cambridge, mass.: harvard uni- versity press, ); idem, pandora’s hope (cambridge, mass./london: harvard univer- sity press, ). . inscription devices are technologies that translate phenomena into signs on paper. . latour, “how to be iconophilic” (above, n. ). were constructed, is not perceived as challenging the works’ status as art; rather, it adds to the pleasure of art: the more you know about the making of a certain painting or movie, the more you will enjoy it. likewise, claiming that there is no work done in creating art would provoke most artists, who state again and again that their work is ex- actly that: work. this is not the case in science, which is not per- ceived as constructing facts, but as uncovering or discovering facts. thus, explicating the work done by inscription devices will be per- ceived as challenging to the sciences, for it will point to the purification work done by the inscription devices—which again indicates the com- plex and contingent layers of work that make inscriptions possible. in science in action, latour describes how the world of the labora- tory opens up to the spectator interested in what lies “behind” the inscriptions when confronted with controversy: “what is behind a scientific text? inscriptions. how are these inscriptions obtained? by setting up instruments. this other world just beneath the text is in- visible as long as there is no controversy.” in the molecular micro- bial ecology group (mmeg), i seemed to have stumbled upon one such controversy, opening up to investigations of the “world be- neath”—the laboratory and its instruments. cambrosio, keating, jacobi, lorraine daston, and various others have written a substantial body of texts analyzing and discussing im- agery in science. these texts are an important backdrop and inspi- ration to this paper. here, i will single out two that have had specific influence on my analyses—but that does not mean that the remain- ing articles have been forgotten. the article “of lymphocytes and pixels: the techno-visual pro- duction of cell populations” deals with visualizations created by sommerlund / beauty and bacteria . for further discussion, see also bruno latour, “the promises of constructivism,” in chasing technoscience: matrix for materiality, ed. don ihde (bloomington: indiana uni- versity press, ), pp. – . . latour, science in action (above, n. ), p. . ibid, p. . . see, e.g., peter keating, alberto cambrosio, and michael mackenzie, “the tools of discipline: standards, models, and measures in the affinity/avidity controversies in immunology,” in the right tools for the job, ed. adele clark and joan fujimura (prince- ton: princeton university press, ), pp. – ; peter keating and alberto cam- brosio, “`going monoclonal’: art, science, and magic in the day-to-day use of hy- bridoma technology,” social problems ( ): – ; peter keating and alberto cambrosio, “biomedical platforms,” configurations ( ): – . . alberto cambrosio and peter keating, “of lymphocytes and pixels: the techno- visual production of cell populations,” studies in history and philosophy of biological and biomedical sciences ( ): – . means of a machine called a facs (fluorescence-activated cell sorter). the facs distinguishes different species of bacteria “me- chanically”: the bacteria fluoresce in different colors, and the facs re- sponds to the differences in type of fluorescence. this differentiation is performed “manually” in a conventional fluorescence microscope such as the cslm. in spite of this difference, the central point of cambrosio and keating’s article—that imaging via the facs tech- nique breaks down the difference between representation and inter- vention—also goes for the cslm technique discussed here. accord- ing to cambrosio and keating, “imaging as embodied in the flow cytometric practices does not simply break down walter benjamin’s distinction between manual (for example, drawings and engraved diagrams) and mechanical (for example, photographs and micro- graphs) reproductions, but goes beyond that to collapse the epistemic distinction between intervening and representing.” this point is very similar to the one i will present in this paper, for the collapsing of “intervening and representing” can be seen as related to the implo- sion of reality and representation that is implied in the transforma- tion of nonoptical events into optical ones. thus, the point sug- gested by cambrosio and keating would be common to fields as different as astronomy, high-energy physics, and microbiology. another paper by cambrosio, jacobi, and keating focuses on paul ehrlich’s images of antibodies and points out that these images rep- resented entities on which there was no consensus: “what made the use of visual imagery so controversial, was that it defined the rele- vant entities by the very process of representing them.” there are many similarities between this situation and the situation my re- searchers find themselves in, for biofilm is a new object of research with new methodological tools offered by molecular biology to eco- logical studies. thus my paper and cambrosio, jacobi, and keating’s configurations . this technology is central in the mmeg laboratory as well, although it was ac- quired only when i was finishing my work there; consequently the facs is not in- cluded in my analyses. . cambrosio and keating, “lymphocytes and pixels” (above, n. ), p. . walter benjamin was an influential german philosopher who published the ground-breaking article “the work of art in the age of mechanical reproduction” in , reprinted in illuminations (london: random house, ), pp. – . the article discusses the technologies of film and photography, and how these technologies influence the sta- tus of the work of art and its special, authentic “aura,” which is constituted by the di- rect physical link between the work and the artist. . alberto cambrosio, daniel jacobi, and peter keating, “ehrlich’s ‘beautiful pictures’ and the controversial beginnings of immunological imagery,” isis ( ): – , on p. . share the focus on how representation shapes the entities repre- sented. the difference is mainly that theirs is a historical study, while mine is real-time and material. upon this note, i will return to the molecular microbial ecology group. the story of acinetobacter and pseudomonas putida after talking to the professor about the picture from nature, i went on to ask the young researcher who had made the picture what was so special about it. he told me that it was actually a part of a se- ries of six, and that it was the story narrated by these six pictures rather than the single picture that was interesting. i asked him about the story, and he gave the following account: (figure ) the series consists of six pictures (fig. ) that represent particular phases of development of biofilms consisting of acinetobacter (red) and pseudomonas putida (blue). the researcher and his colleagues had a hypothesis about these species: that together they were able to de- grade the organic solvent toluene. when the two species grow on a bases of benzyl alcohol (replacing toluene), they go through differ- ent stages of cooperation: acinetobacter is able to metabolize benzyl alcohol and excrete benzoate, which p. putida can metabolize. from the outset, the two bacteria live almost evenly scattered over the sur- face (a). however, it soon becomes obvious that p. putida is attracted to acinetobacter, probably because of the excreted benzoate—this is visible because the active cells of p. putida (those that eat) shine with a greenish light. the next day (b), acinetobacter starts to develop mi- crocolonies, and p. putida gathers around these colonies. on the third day, large microcolonies of acinetobacter are formed, with active p. putida cells around and on top of them (c–d). on the sixth day of the development of the biofilm, the large microcolonies have disinte- grated, and acinetobacter starts to migrate into the higher levels of the substratum (e–f). this probably happens because p. putida is so close to the acinetobacter that it no longer gets the nutrients it needs. at first, i was simply baffled by the story, as i had no idea how the single picture-frames a–f were connected to the stages in the story. the exploration of these connections is very much what my coming analyses will consist of. second, i was also a bit disappointed with the story in itself—i had expected something more dramatic after the introduction (it is not the single picture, it is the story that is interesting), perhaps a classic story of the rise and fall of a community. i had hoped that sommerlund / beauty and bacteria . however undramatic, the story does have the basic characteristics of a narrative: it is structured in time; it has a fixed beginning, middle, and end; and it has a specific configurations figure . haagensen, the story of acinetobacter and p. putida (unpublished images: cour- tesy of the author). the researcher would tell me more about the aesthetics/science schism. but to the young researcher the term “story” seemed to be more prosaic than it was to me; or perhaps the story of acinetobacter and p. putida contained high drama within the context of microbiol- ogy, and i was simply not able to understand it. later, i was to discover that even for me, there was high drama to be found in this story: the translation of the story to a single picture in many ways serves as an analogy to the process of translating and purifying scientific practical work into science. thus, the compli- cated relation between image and narrative implied by the re- searcher had an impact on many topics other than that of acineot- bacter and pseudomonas. more about that later on. the construction of a sign system i went on to ask the researcher who had made the picture if i could spend some days in the laboratory with him to see how the biofilm pictures were made. in the laboratory, it soon became appar- ent that a major issue when working with biofilm is to make visible the things you want to demonstrate. first, the researchers want the different species of bacteria to be distinguishable. even when the bacteria grow species by species in a petri dish, it can be difficult to tell them apart: some may be oblong and others circular, and that is about all the difference there is. when more species are grown to- gether in a glass chamber—which is how biofilms are grown in the laboratory—you have no chance of telling them apart by morpho- logical differences. second, the researchers want to be able to see whether bacteria of different species are living next to each other or to- gether. for instance, the biofilm depicted in nature is interesting be- cause the two species may feed off each other. how do you show that? the young researcher needed a representative system: a vocab- ulary to tell the story of the biofilm. the molecular microbial ecology group laboratory has made the construction of sign systems somewhat of a specialty: the re- searchers use probes to mark the different strands of bacteria with sommerlund / beauty and bacteria causality. it should be noticed, though, that the causality originates from the bacteria rather than the “author”—the researcher. in this respect, reality and the representation of it are intermingled in the most intimate way. . the most commonly discussed sign system is human language. umberto eco, in a theory of semiotics (bloomington: indiana university press, ), points to many more, such as zoology, olfactory signs, tactile communication, medicine, music, plot structures, mass communication, and written and visual languages. in the fashion sys- tem ( ; london: cape, ), roland barthes also mentions the fashion system, and i will add scientific systems to the list. colors. these probes consist of specific dna sequences that hook on to bacterial rna, and they are marked with different fluorocromes— that is, with different colors. the use of probes is routine in the lab- oratory, and the probes are commercially available. how the com- mercial laboratories make the probes and how the probes actually connect to the bacteria remain a black box to the researchers —they simply order the probes from a catalogue, as others would order art supplies. by means of these probes we enter the world of significa- tion, the making of meaning—a world that can fruitfully be dis- cussed using concepts from semiotics. therefore, i will turn to semi- otics and discuss the color marking of bacteria in this light. a basic claim within semiotics is that the signified (the concept of acinetobacter) is arbitrarily connected to the signifier (that which refers to the concept, in this case the word “acinetobacter,” or, in a picture, a red dot). this means that another sound or different let- ters would be just as efficient in referring to the bacteria as “acineto- bacter,” as would a different color than red. the connection is not given by nature, but is the result of a cultural and arbitrary defini- tion. the sign system considered here—the color-marking of strands of bacteria, and the visualization of their level of activity—is special, for the link between signifier and signified has not yet been estab- lished. the unmodified, wild-type bacteria are out of reach of the re- searchers and only come within reach through the process of signi- fication, a process that can be followed in the laboratory and that leaves no doubt as to the arbitrariness of the sign. this is an example of how turning nonoptical events into optical events also means re- moving boundaries between representation and intervention. configurations . for further discussion of scientific techniques and their becoming “black boxes,” see kathleen jordan and michael lynch, “the sociology of a genetic engineering tech- nique: ritual and rationality in the performance of the ‘plasmid prep,’” in clark and fujimura, right tools for the job (above, n. , pp. – . the article is an analysis of the “plasmid prep,” a technique that is also used extensively in the laboratory in ques- tion, and that has a status in many ways equal to the ones i discuss here. . in laboratory life (above, n. ), latour and woolgar use bachelard’s concept of “rei- fied theory” to designate this type of technology. . ferdinand de saussure perceived the sign as a whole comprising a signifié (concep- tual content; henceforth, “signified”) and a signifiant (expression; henceforth, “signi- fier”). the relation between signified and signifier is arbitrary, which means that there is no natural connection between these two sign levels. by denaturalizing the connection between signified and signifier it is possible to discuss the human language—as well as other sign systems—as classificatory systems. poststructuralists have later claimed that not only is the relation between signified and signifier arbitrary, the signified itself is arbitrary and is constituted by the signifier—not the other way around. see ferdinand de saussure, course in general linguistics ( ; london: duckworth, ). in the laboratory, the connection between signified (“bacteria”) and signifier (the colored dot) was made as follows: the researcher set up the flow chambers containing the biofilm in a system of tubes and pumps that ensured the circulation of nutrients through the sys- tem. the biofilm was then left to grow for a few days. when it was ready to be photographed, the researcher turned off the pump and removed the flow chambers containing the biofilms that were to be photographed; he then took a syringe filled with ice-cold fixative (silicone rubber) and injected it into the flow chambers, a procedure that killed the bacteria in the biofilm. the six pictures represent stages in the development of a biofilm. but making a cslm-picture kills the biofilm, and hence the single photographs in the series are of different biofilms. thus, the picture- series representing the development of one microcolony in one biofilm is made using six different biofilms. the researcher then applied the probes to the silicone with an- other syringe and told me that they would spread through the sili- cone and hook onto the rna of the bacteria, thus making the or- ganisms in the biofilm visible. in the case of acinetobacter and p. putida, two probes were added to the silicone (red for acinetobacter, blue for p. putida), and this way the two actors of the story were put in place. however, in order to tell the story of the two strands of bacteria, the researcher needed yet another color code. the actors had been coded red and blue, but an indicator of interaction was necessary to combine the two codes into a story line. this procedure had been performed before i started my observations: the interaction indicator had been spliced into the dna of the two strands of bacteria con- tained in the biofilm; consequently, the following is based on what the researcher told me, and not on my own observations. the in- dicator is called “gfp” (green fluorescent protein), and it is as institu- tionalized as the probes mentioned above. gfp was originally iso- lated from a fluorescent jellyfish, aequorea vintoria; it is used for gene encoding, or more specifically to show when a gene is induced, or “turned on.” in the case of acinetobacter and p. putida, gfp can be used to show whether p. putida’s metabolic system is more active when placed close to acinetobacter than it is elsewhere. in other sommerlund / beauty and bacteria . even if i did not observe the researcher splice gfp into acinetobacter or p. putida, i feel fairly familiar with the procedure, as this was one of the experiments i performed myself when being “trained” prior to making observations. . during the past five to ten years, the natural gfp protein has been heavily mutated; thus, bfp (blue fluorescent protein), yfp (yellow fluorescent protein), etc. are all com- mercially available—again, just like art supplies. words, if p. putida can eat what comes out of acinetobacter, they will shine with a greenish light. the practice of color encoding is routine and black-boxed, but every time a researcher performs the procedure it is at least theoreti- cally possible to create a new color code and make the invisible visible in a different way. there is no “natural” line between visible and in- visible; rather, the boundaries are based on the practical choices that researchers make in specific cases. even more strikingly, though the goal of this experiment may be to examine the toluene-degrading capabilities of microbial communities, laboratory time is primarily spent working with signification. there is no mystery to this, for there is no way of examining toluene-degrading capabilities without in some way making them visible or detectable. in the words of hans-jörg rheinberger, “representation is ‘eventuation’ (it is about intervention, invention, and the creation of events).” this questions the practical relevance of the schism between aes- thetics and science: in practice, there is no clear line separating the two. however, the researchers’ verbalizations continue to differenti- ate sharply between them. this differentiation will be the object of discussion below. “subjectivity” when the researcher chose red and blue and not two other colors to mark his bacteria, this was simply because “these colors stand out against each other nicely”—as he said in the laboratory. later, in an interview, he developed the point further: d: for acinetobacter, i chose a red probe, but i might as well have chosen a green one or a blue one. . . . js: then why did you choose red? d: i chose the red probe because that is what people have done earlier. and people have used the blue for putida. js: so, it’s becoming a code? d: it is becoming a color code—or at least it is within this group. i do not know if other groups use other codes. it is also a question of what you have in the freezer. and of course, you should not use green because the gfp monitor is green, so of course you will have to think about that. but otherwise, it is about what is in the freezer, and what other people have done with the bacteria you are working with. configurations . hans-jörg rheinberger, toward a history of epistemic things—synthesizing proteins in the test tube (stanford: stanford university press, ), p. . what struck me—both during my observations in the laboratory, and later while doing the interview—was that the researcher seemed to dismiss all questions about color and choice of motif. they seemed to be unimportant to him, and he could not understand why i found the subject interesting. nevertheless, this specific re- searcher is known within the group to be a specialist when it comes to constructing and representing biofilms. to a layperson, the pic- tures are intriguing because of their beauty. i was mystified that the young researcher did not show more pride in this aspect of the pic- tures, and in the fact that even outsiders found them interesting. one way of understanding this could be to consider what the re- searchers refer to as the subjective quality of the photos. subjectivity, when defined by these researchers, seems primarily to be about ex- plicitness in choice of motif. the choice of photographing one micro- colony rather than another is perceived as being highly subjective. in the following, another researcher from the group explains why this is the case: because it is really very chaotic what goes on in one of those biofilms. so, it is very . . . i don’t know if the others have told you, but often when they make pictures for publications, they scan more biofilms to find the best place that shows exactly what they want to show. especially . . . acinetobacter and putida . . . those nice pictures they have. everybody who works here knows that these kinds of pictures that make it to that kind of publication . . . they have spent maybe half an hour scanning the entire biofilm to find the best place, and then you say, it looks like that and that, and you’ve got this gorgeous picture to underline your hypothesis. but somehow it is not very scientific, doing that, but everybody does it. i guess somehow it’s ok. the researcher quoted above regards “subjectivity” as being in op- position to “science.” almost all the researchers of the group echo sommerlund / beauty and bacteria . alex pang notes a similar inclination toward aesthetic considerations in astron- omy, and quotes a late nineteenth-century astronomer as saying, on the introduction of photography to astronomy, that “stars should henceforth register themselves”; pang goes on to state that “aesthetics would not even exist in this new order. `their pictor- ial beauty,’ the review [“astronomical photography,” edinburgh review, ] said of astronomical photographs, ‘is the least of their merits,’ and comparisons of pho- tographs would be made without considering whether one was more beautiful or strik- ing than another” (alex pang, “technology, aesthetics, and the development of as- trophotography at the link observatory,” in inscribing science, ed. timothy lenoir [stanford: stanford university press, ], pp. – , on p. ). . not all researchers are as shy of speaking of the aesthetic qualities of their work. for instance, james d. watson speaks freely of aesthetics in his account of the “discov- ery” of the double helix, often saying that the prettiness of the figures was an impor- tant standard of truth in the work of constructing a visual representation of dna: james d. watson, the double helix ( ; london: penguin books, ). this viewpoint, and the quote is intended to illustrate a general point rather than an individual statement. subjective matters may be rele- vant when discussing art, but proper science is objective. william j. mitchell describes this stance as being typical in scientific—and pho- tographic—procedures: such exclusion of human bias is the point of many standard scientific proce- dures, such as random sampling, double-blind clinical trials, and setting the statistical significance levels before conducting experiments. . . . the photo- graphic procedure, like these scientific procedures, seems to provide a guaran- teed way of overcoming subjectivity and getting at the real truth.” likewise, lorraine daston and peter galison write of scientists’ use of mechanically produced images in the late nineteenth century that, at issue was not only accuracy but morality as well: the all-too-human scien- tists must, as a matter of duty, restrain themselves from imposing their hopes, expectations, generalizations, aesthetics, even ordinary language on the image of nature. where human self-discipline flagged, the machine would take over. wary of human intervention between nature and representation, [scientists] turned to mechanically produced images to eliminate suspect mediation.” this—the alleged connection between mechanically produced images and objectivity—could explain why the researcher did not re- act positively to my attempts toward a more aesthetic discussion of his pictures, even though their aesthetic qualities are very much “in your face.” according to galison and daston, aesthetics and beauty are phenomena that are morally tainted in science, like subjectivity, and that the researchers should avoid—or at least ignore. seen from this angle, it is not so strange that the young researcher tried to avoid discussions of something as “subjective” and “nonscientific” as colors and choice of motif. still, the practice of making the pho- tographs legitimately entails both types of consideration: it is not ei- ther aesthetics or science; rather, it seems that science in this case could not exist without aesthetic considerations. comstat: new biofilm representations after this discussion of the preparation of the cslm-pictures and the experimental and biological “content” of these visualizations— that is, the color-marking and thereby the visualization of the bacteria configurations . william j. mitchell, the reconfigured eye (cambridge, mass./london: mit press, ), p. . . lorraine daston and peter galison, “the image of objectivity,” representations ( ): – , on p. . in the biofilm—i will go on to discuss the making and editing of the cslm-photographs. however, before doing this i will consider an- other type of visual representation of the biofilms, namely com- stat-diagrams, because it makes analytical sense to consider com- stat at this point. comstat is a piece of software that analyzes stacks of images produced by the cslm, and produces diagrams to represent these analyses. as argued by ferdinand de saussure, signs acquire meaning not through their relation to reality, but rather through their relations to other signs. when i was trying to understand how to make and read cslm-photographs, the researchers kept referring to comstat and telling me that i should really look into those representations as well. this suggests that the two types of representation give meaning to each other through their difference. i asked the professor for his interpretation of the meaning of comstat. he told me that com- stat was able to generate other types of representation of biofilms than the somewhat problematic cslm–photographs: by measuring different parameters randomly across the biofilm, the software could generate quantitative rather than qualitative data. thus, the more “subjective” (and thereby aesthetic) extra meanings of the pho- tographs would be countered by representations that were more tra- ditionally scientific. sommerlund / beauty and bacteria . the sign is often classified into different types. famous among these is the triad of charles sanders peirce: icons, indices (often called “indexes”), and symbols. the iconic sign is the sign type i work with in this paper. it is characterized by resembling the con- ceptual object (“signified,” in saussure’s terms); the usual examples are photographs, paintings, sculptures, and cinematic signs, but mathematical signs such as graphs and curves can also be put into this category. peirce would say that both types of signs (pic- tures and graphs/curves) are icons, and thereby equally arbitrary. but even though after having spoken to the professor, i went on to talk to the re- searcher who worked on the comstat software. i asked him why the comstat program was so important. i will quote from this in- terview at some length: h: it [comstat] is not as subjective as the cslm-pictures. when you look at one of these biofilms, it shouldn’t be like ... you look at one biofilm and another biofilm, and then you go: nahhh, i think this one is a little bigger, and this one is a bit thicker and this one’s a bit thinner. if you do that, it becomes very subjective. like, in some way, you know what you want . . . . js: ok, so it’s the quality of the description that gets better? h: yes, the quality gets better. the numbers in themselves aren’t that interesting at all. but the quality gets better because you dis- cover that maybe it wasn’t right what you thought you saw, be- cause you wanted to see something specific. js: the cslm-pictures are really difficult to look at, or so i think. or maybe you get better . . . . h: it is difficult, and i think that one thing that is difficult about our way of doing research is that we’re really marked by our mod- els, or not models, but when looking at the biofilms we have strong hypotheses of why things are the way they are. and it is hard to look at them without having a hypothesis. it is difficult to look at them in a completely objective way . . . . so, the idea with this program is to quantify how these things look three-dimen- sionally. js: but even with the program, there must be some prior under- standing . . . . there must be some boxes to put the results into? h: sure. i decided what variables were to be calculated, like the thickness of the biofilm, and how big the surface is. sure, that’s sort of a model that i have chosen. i chose to describe the biofilm this way. js: how did you decide which variables and parameters to work with? h: i just took all i could think of, and then i ordered it according to rank. an immediate and intuitive thing: when something configurations peirce—who worked as a chemist and mathematician as well as a semiotician—might regard cslm-photographs and graphs as having the same status, the lack of color and the randomness of choice of motif made the graphs, curves, and numbers more palat- able to the microbiologists. grows on a surface, then how thick is it? the next thing that comes to mind is: how much does it vary, is it very flat or does it go up and down? that’s “roughness.” the next thing that comes to mind is: how big is the surface of this one, that’s important, be- cause how does fluid get in and out of this biofilm? and then there are a number of variables further down. the researcher refers directly to the “subjectivity” of the cslm- pictures as constituting a problem. at the same time, he describes the outline of the comstat program as neutral and objective, in spite of his “i chose to describe the biofilm this way.” his descrip- tions of the variables chosen as descriptive parameters of the com- stat-representation seem logical and obvious—however, it is also obvious that other variables could have been chosen, or they could have been ordered in a different way. thus, it seems that the creator or designer of the representations is as present in the comstat- graphs as he or she is in the cslm-pictures. however, the quantifi- cation, abstraction, and generality of the comstat-representations make them seem more scientific. relevant to this point, latour addresses the creation of diagrams and graphs representing the soil of the rain forest. he describes this process as simultaneous reduction and amplification: the researchers reduce materiality, locality, and multiplicity, and they amplify com- patibility, standardization, and so forth. he writes: “in losing the for- est, we win knowledge of it.” likewise, in the comstat-represen- tations, the researchers lose the biofilm, but win knowledge of it. in the eyes of the microbiologists of the molecular microbial ecol- ogy group, the graphs obviously belong to a different class of repre- sentation from the cslm-photographs. i use the plural—“microbi- ologists”—deliberately, since this researcher’s views are repeated by the majority of the researchers in the group; i presented an early draft of this analysis to the group at a research seminar, and the re- sponse was unanimous: the comstat representations are more scientific, because they are more objective, which again makes them more true. as rheinberger writes, the sciences aim at true representa- tions of the world. in this case we have two, very different, repre- sentations of the same “world”; the question then becomes, which is truer? the two types of scientific representation are common to many branches of science, and may be categorized using marie-josé sommerlund / beauty and bacteria . latour, pandora’s hope (above, n. ), pp. . . rheinberger, toward a history of epistemic things (above, n. ), p. . bertin’s terms graphisme (polysemic imagery, such as pictures and photographs open to multiple interpretations—in the present study, akin to cslm-photographs) and graphique (monosemic data repre- sentation such as diagrams that have only one predetermined inter- pretation—here, comstat-diagrams). peter galison presents a re- lated differentiation in image and logic, where he describes two types of visual scientific traditions. one, the image-tradition, makes visu- alizations that have as the ideal “images . . . that are presented . . . as mimetic—they purport to preserve the form of things as they occur in the world”; in the present study, these mimetic images can be compared to the cslm-photographs, while the comstat-diagrams can be seen as a part of the other tradition that is marked by an ideal of logic, which again visualizes using machines that are “counting (rather than picturing) . . . aggregate masses of data to make statisti- cal arguments for the existence of a particle or effect.” the latter class of scientific representation seems to be performed by a researcher who is an innocent medium rather than an active creator. many trends within science studies (notable in this con- text is the feminism of, e.g., donna haraway) criticize this way of re- garding science and scientists: the sciences’ claim of seeing every- thing while remaining invisible is a “god trick,” a claim that the scientist’s position does not influence the knowledge produced. in the present study, the comstat-representations of biofilm do not point as explicitly to the “author” as do the cslm-photographs, but they are still dependent on authors and subjective choices, as the above interview clearly shows. they are not made by a “god,” and some “subject” other than the computer has chosen the parameters used for scanning the biofilm, even when computers do the scan- ning randomly. thus aesthetics and form, in the sense of composi- tion, are included in the comstat-representation to the same de- gree as they are in the cslm-photographs. configurations . marie-josé bertin, la graphique et le traitement graphique de l’information (pairs: flam- marion, ). for further discussion, see cambrosio and keating, “of lymphocytes and pixels” (above, n. ). . peter galison, image and logic (chicago: chicago university press, ), p. . . daston and galison, “image of objectivity” (above, n. ), p. , note that “let nature speak for itself” became the watchword of a new brand of scientific objectivity that emerged in the latter half of the nineteenth century. at issue was not only accu- racy but morality as well: the all-too-human scientices must, as a matter of duty, re- strain themselves from imposing their hopes, expectations, generalizations, aesthetics, even ordinary language on the image of nature. . it is also useful to compare to cambrosio, jacobi and keating’s discussion, in “arguing with images” (above, n. ), of “figuration” and “demonstration.” ideally, making and editing cslm-photographs i now return to the analysis of cslm photography, since the con- struction of sign systems and the creation of visualizations and sto- ries do not stop at the coloring of bacteria: the researchers also have to capture the colors on film and make them into photographs. this part of the representational practice requires as much work and con- sideration as the first one. the cslm that makes the pictures of the biofilm is not one simple piece of equipment, but rather a cluster of machines taking up most of one room, and an extended network of apparatus. this was where i went with the researcher after he had killed the bacteria and in- jected the probes. the room containing the cslm is very different from the benches where most laboratory work takes place: the latter benches are well lit, fully occupied by researchers and technicians, and bustling with small talk, music, and jokes; the room where the cslm is placed is dark and quiet, for only one person at a time can work there (or two, if one is observing the other). the researcher and i started out by transporting the biofilm system on a trolley to the cslm room. the researcher then disengaged glass chambers from the system, and placed them under the microscope. he looked, and asked if i wanted to have a look, too. while i was looking, he ex- plained that a laser makes it possible to see how the biofilm is orga- nized inside. however, he added, there is an important trade-off con- nected to this procedure: each time the laser cuts through the biofilm, it bleaches out some of the color. thus, the more layers are cut, the better the picture; but the better the picture, the more the motif vanishes, making it impossible to produce any future pictures. when the researcher had found a good place on the biofilm, he took pictures, which could be seen momentarily on a computer screen to the right of us. he started editing the image right away; this, he said, is always necessary because the cslm tends to blur the colors: “the cslm does not register the colors clearly.” i looked into the microscope to check how the pictures were supposed to look— assuming that the image in the microscope would be the “original” sommerlund / beauty and bacteria “figuration” is the process that “concretizes notions” (p. ) by giving them graphic form; this process can be likened to the work that lies behind the cslm-images. “demonstration” builds on figuration and partakes in “show-and-tell exercise [rather] than logical proof” (p. ). in practice, these authors argue, these two types of visual- izations are superimposed and intertwined, as is also the case when regarding the cslm/comstat-representations. we were trying to re-create on the computer screen and subsequently on paper. however, it was very difficult for me to tell what was in- significant blur and what was significant variation. this was true for the color-tagging as well as the gfp markers: it was impossible for me even to establish how the original looked. i asked the researcher, who was sitting next to me editing the picture, how he could be sure that what he was doing on the screen was “correct,” when it was so difficult to see what the original looked like. judging this, he an- swered, is a matter of practice. having said that, he continued changing the blur into clarity: violets were changed into reds, grays into blacks, and turquoise into greens. the blurry quality of the line between reality and representation, and the interpretation necessary to decide whether turquoise “re- ally” means blue or green, are aspects that the researchers are very fa- miliar with. to illustrate this, i will quote another researcher from the molecular microbial ecology group: f: you have to touch it to understand it—i guess you do, too? it is a funny abstract way one makes it [the pictures]. you have some colored dots, and then you can make a lot out of that. it must be damned abstract for people coming from other areas. to me it is very simple . . . easy to understand . . . but i have to admit that it is difficult to explain. especially to explain how we make conclu- sions . . . . it is hard to explain what we see from green and red. it has to do with legitimate interpretations. how much can you de- fend to put into those interpretations? there is a line . . . js: how do you establish that line? f: it is something you learn from routine and experience . . . how much can you conclude from such a thing, and where is the line? where do we stop? at which point can we no longer believe what we say? these are some of the hardest things. by referring to tacitness, routine, and experience, this researcher stresses the contingent nature of scientific work. in effect, this was also what the researcher i observed did, when he dismissed my questions as configurations . samuel edgerton and michael lynch notice something similar within astronomy: “what aesthetics means [in astronomy] is not a domain of beauty or expression which is detached from representational realism. instead it is the very fabric of realism: the work of composing visible coherences, discriminating differences, consolidating enti- ties, and establishing evident relations. . . . this hands-on process of “interpretation” can be treated as an art situation within the performance of scientific practice” (samuel edgerton and michael lynch, “aesthetics and digital image processing,” in picturing power, ed. gordon fyfe and john law [london/new york: routledge, ], p. ). based on lack of practice. this is very interesting, for the trait com- monly connected with hard science would be universality and not con- tingency. in regard to the cslm-photographs, however, the researchers stress contingency as legitimizing the scientific status of the pho- tographs (and not, as might be expected, the opposite), thus again suggesting that science and aesthetics cannot be seen as opposites in connection with the cslm-pictures. likewise, the researchers stress interpretation as being a crucial task when working with the pictures. in- terpretation is traditionally connected to aesthetics and not to science, hence the concepts of “interpretive sciences” and “exact sciences.” this stresses that even references to universality and contingency, respec- tively, are contingent, and a part of the artisanal practices of science. the extra meanings of photography photography in itself bears many extra meanings that add to the meanings of the cslm-photographs and influence their scientific status. a photograph (of, e.g., a bacterium) can be argued to be an icono- graphic sign: a signifier that refers to the signified by means of physical resemblance; interestingly, so is a graph. the signified in this case is a system of bacteria, which has been placed in a specific situation— a now—that has been immortalized on the filmstrip. in “rhetoric of the image,” roland barthes argues that photography holds a special status within sign systems, which originates in a direct link to the re- sommerlund / beauty and bacteria . karin knorr cetina, in epistemic cultures (cambridge/london: harvard university press, ), notes that the senses play very different roles in the two branches of sci- ence studied, particle physics and molecular biology. in molecular biology, she argues, the sensory body is important as a secondary tool: materials are continuously visually inspected, and on this background the status of the experiment, photograph, etc. is de- termined. likewise, the researchers studied by knorr cetina—and the ones studies by me—underlined the importance of “being there” in the laboratory. even researchers with many junior researchers and laboratory technicians working for them insisted on doing important experiments “with their own hands”. . it has also been argued that pictures depict through denotative symbols. for fur- ther discussion, see mitchell, reconfigured eye (above, n. ), p. . . rheinberger (toward a history of epistemic things [above, n. ], p. ) notes that scientific representations follow the sign triad of charles sanders peirce: symbols (analogies, hypothetical constructs), icons (models or simulations), and indices (ex- perimental realizations). it is interesting that both cslm and comstat representa- tions are icons (although their histories include different types of signs—e.g., indexes in the form of experiments), while at the same time they represent the two primary representational traditions pointed out by peter galison in image and logic (above, n. ). this suggests that the type of sign is extremely plastic as regards content, and that differences in respect to attitudes toward them should be found elsewhere. ality it refers to; in comparison, other sign systems are completely cut off from reality—not referring to reality, but addressing that which we think of as reality in what seems to be naturalness. this characteristic of the photographic medium—that it holds a special status among sign systems because of a closer correspondence to reality—means that photography in some aspects resembles “hard science,” which also claims a special status (among epistemological systems) because of a closer correspondence to reality. this is com- mented on by mitchell, who writes: “we feel the evidence it presents corresponds in some strong sense to reality, and (in accordance with correspondence theory of truth) that it is true because it does so.” he continues: “we have come to regard [photographs] not as pictures, but as formulae that metonymically evoke fragments of reality.” thus, this characteristic of the photographic medium brings the photograph closer to the core of hard science: it is perceived as an objective, neu- tral investigation of something already existing. this is what mitchell calls “the extraordinary tenacity of the camera’s claim to credibility.” barthes´s claim that photography holds a privileged position when it comes to referring to reality can be disputed—and has been so by the later barthes, among many others. for instance, w. j. t. mitchell writes the following of the postmodern “pictoral turn”: whatever the pictorial turn is, then, it should be clear that it is not a return to naïve mimesis, copy or correspondence theories of representation, or a re- newed metaphysics of pictorial “presence”: it is rather a postlinguistic, post- semiotic rediscovery of the picture as a complex interplay between visuality, apparatus, institutions, discourse, bodies, and figurality. on a less philosophical note, it has become obvious to all that the photographic medium is no more innocent than any other medium. thus, it can be claimed that photography—both before and after the button is pressed—holds a number of possibilities of manipulation in regard to the cslm-photographs. i regard this manipulation as being divided into three main categories: selection, manipulation, configurations . roland barthes, “rhetoric of the image,” in image, music, text, ed. stephen heath (new york: hill and wang, ), pp. – . . mitchell, reconfigured eye, (above, n. ), p. . . ibid, p. . . ibid. . roland barthes, camera lucida (london: flamingo, ). . w. j. t. mitchell, picture theory (chicago/london: university of chicago press, ), p. . and editing. through these examples of manipulation, photogra- phy is also removed from science and pushed toward aesthetics. first, the very selection of a motif can be seen as an instance of manipulation. many photographs would not only look different, they would also mean something different if what has been left out were still in the frame, or vice versa. in relation to the work done in the molecular microbial ecology group, this is what most of the re- searchers stress as a problem when explaining to me the pros and cons of cslm-pictures: it is only too obvious that an individual has selected the motif—it has not presented itself, and it has not been chosen randomly. second, the motif itself can be manipulated. to say that the mo- tifs of the cslm-pictures are heavily manipulated is no exaggera- tion: the natural setting that the pictures refer to has very little to do with glass chambers, tubes, and pumps in a laboratory. likewise, the bacteria in the chambers are not the same as those they represent: the wild types are not blue or red, and they are not able to shine with a green light when their metabolic systems are activated. third, much can be done during editing. in the rough end of the spectrum, shapes can be inserted into and removed from the picture; and in the more refined end, colors can be made brighter, fragments highlighted, and so forth. editing the cslm-photographs is a major task, the purpose of which is precisely to make the unclear become clear. in conclusion, the medium of photography contains forces that pull it toward the core of traditional science (the direct link to real- ity established through the physical resemblance to reality—that which mitchell calls the correspondence-theory quality of pho- tographs), while others pull it toward aesthetics (selection, manipu- lation, editing). thus, photography acquires a peculiar duplicity in its relation to reality: it can be perceived as the most “genuine” medium (when perceived in the commonsensical way of “rhetoric of the image”), but also as the most “fake” one (which should be ob- vious from the list of manipulations above). thereby it also acquires a double status in relation to the scientific status of work that uses photography as representation and documentation. this point can be illustrated further through galison and daston’s discussion of “mechanical objectivity,” which analyzes how, histori- cally, the very mechanism of the mechanical representations was taken as a token of objectivity. this somewhat naïve belief that ob- sommerlund / beauty and bacteria . william j. mitchell’s discussion of “intention and artifice” in photographs (recon- figured eye [above, n. ] pp. — ) suggests that this is characteristic of photographs in general. . daston and galison, “image of objectivity” (above, n. ). jectivity can be ensured by mechanism has been tainted (we all know famous examples of “photos that lied”), and the photograph now holds a paradoxical double status in regard to subjectivity and objectivity: on the one hand, it is still seen as the most objective rep- resentative medium; and on the other hand, we all know that pho- tographs can be manipulated, chosen for the purpose, edited. . . . the researchers at the molecular microbial ecology group seem to perceive the forces that push the photograph toward aesthetics to be as powerful as the forces pulling toward science. in galison’s book image and logic, he describes the “image-tradition” and the “logic- tradition” as equally strong within physics. if this goes for biology as well, this could explain the researchers’ need for representations from both traditions. in contrast, the layman seems to perceive photography as more reliable than graphs and diagrams. one way of understanding this difference between scientists and the rest of us is to consider the practical work that goes into the photographs, both in the sense of working with the motif (color-marking the bacteria) and in editing. it is obvious to anybody that these pictures are not the result of holding a snapshot camera over a lump of bacteria. this also means that technology is very visible in the photographs. they do not offer an easy way just to look at the bacteria represented; on the contrary, you are struck by questions such as how did they make this? how did they color the different strands? how is the -d effect achieved? it should be noted that these questions relate to the technology and work-practices, and not to the bacteria. technology and practices end up being an implicit—but very important—motif, as is the case with works of art. this is underlined by the fact that some researchers ex- press great pleasure in technology: the visibility of technology means the visibility of practical skills—the mastering of that technology. you could say that the photographs function as starting points of different chains of signifiers: one connoting the explicit, scientific meaning of the pictures (acinetobacter, p. putida, benzyl alcohol, gfp, metabolism, toluene-degrading), the other connoting the implicit, aesthetic meaning of the pictures (techniques [gene splicing, prob- ing], technology [cslm], skill, artistry, creativity.) from this per- configurations . galison, image and logic (above, n. ). . i think of the cslm-photography as a medium that refers to itself, just like certain traditions within visual arts. traditions such as cubism point to the work of applying paint to the canvas, and the work of the eye in deciphering that paint and making it into a picture, as much as they point to the motif. the motif can almost be perceived as an “alibi,” and the result is a merger of representation and that which is represented. spective, the sign-chains are equal, and it is no longer possible to separate denotative and connotative meaning. instead, both sign- chains become connotations, underlining how “denotation is not the first meaning, but pretends to be so; under this illusion, it is ul- timately no more than the last of the connotations.” conclusion aesthetics and science are intertwined in a very basic and practi- cal sense in the making of cslm-photographs. at the same time, tra- ditional scientific representations (such as those produced by the comstat program) are as constructed as the photographs. the es- sential difference to the researchers is that construction is not as vis- ible in the comstat-representations, which makes the representa- tions seem less aesthetic and thus more scientific. the schism between aesthetics/construction and science/inves- tigation seems almost irrelevant when observing the practice of the researchers. their practice utterly blurs the boundaries between the two and implodes the difference between representation and reality. however, there are still boundaries to consider; they do exist and do have practical consequences for the researchers. they exist as dis- courses within the scientific community and play decisive roles in many of the researchers’ practical representational choices. the sta- tus of the cslm-photographs—as boundary objects between science and aesthetics, between which strong demarcations can also be found—is something of a paradox: they are both the flagship and eye-catching device of the group—its face to the world—and some- thing to be trivialized and joked about. interestingly, through my narration of the story of the cslm-im- ages and the comstat-graphs, a series of concepts have been pre- sented—concepts that can themselves be regarded as elements in a narrative, and analyzed as such. the elements i refer to are placed in a dichotomous relation throughout the story. on the one side we find images, which were linked to aesthetics by the researchers in the beginning of the paper, and later to subjectivity by the same re- searchers. subjectivity was linked to scientific practice, for no researcher would deny the presence of real and embodied researchers in the lab- oratory. last, scientific practice was linked to narratives, first by the re- searcher who told the “real story” of the pictures of pseudomonas putida, and second by me in narrating the story of the images. on a sommerlund / beauty and bacteria . roland barthes, s/z (london: cape, ), p. . . in setting up dichotomous structures to analyze narration, i am inspired by algir- das julien greminas, strukturel semantik ( ; copenhagen: gorgen, ). more general level, narrativity seems to be better able to capture practices, because it is stretched out in time as practices are, and it suits the type of real-time study that i have sought to conduct here. on the other side of the dichotomy, objectivity was linked to science —through the description of aesthetics and subjectivity as nonscien- tific. thus, science was equated with “science” and not with “science in practice,” which is obviously performed by real researchers in real time, and is hence deemed subjective. science was then linked to truthful images because scientific truth is expressed in images (images performing the work of correspondence theory, presenting fragments of reality). the cslm-images are the epitome of the efforts of the lab- oratory, the result of the purification work of inscription devices. it is extremely important to notice, though, that the point of this paper is not to point out some dichotomous relation between science and aesthetics. rather, it is the opposite: the important thing to no- tice in the presented dichotomy is the presence of the image on both sides of the dichotomy. here is an occasion of “slippage”: the “dou- ble nature” of the image underlines the point that a neat dichoto- mous split between science and aesthetics is never complete, because that which is cut out of science is also a prerequisite for science. in the laboratory in question, this double nature of the relation be- tween science and aesthetics means that the aesthetically beautiful cslm-photographs function simultaneously as the laboratory’s crown jewel and as a back door through which all kinds of muddy, contingent, and “nonscientific” phenomena can slip in. acknowledgments for insightful comments and readings, i would like to thank signe vikkelsø, the anonymous referees at configurations, and editor jim bono. also, i would like to thank the molecular microbial ecology group for treating me with courtesy and hospitality. the research for this paper was made possible by a grant from the corrit-foundation (danish technical university) and an internal grant from copen- hagen business school. configurations possible worlds and the beauty of god possible worlds and the beauty of god mark ian thomas robson st robert of newminster catholic school, biddick lane, washington, tyne and wear, ne af e-mail: robson.m @sunderlandlearning.net abstract: in this paper i explore the relationship between the idea of possible worlds and the notion of the beauty of god. i argue that there is a clear contradiction between the idea that god is utterly and completely beautiful on the one hand and the notion that he contains within himself all possible worlds on the other. since some of the possible worlds residing in the mind of the deity are ugly, their presence seems to compromise god’s complete and utter beauty. in this paper i want to explore the relationship between the idea of possible worlds and the notion of the beauty of god. i argue that there is a clear contra- diction between the idea that god is utterly and completely beautiful on the one hand and the notion that he contains within himself all possible worlds on the other. since some of the possible worlds residing in the mind of the deity are ugly, their presence seems to compromise god’s complete and utter beauty. let me try to give the reader an idea of the contradiction by way of this short parable: you have been invited to the house of a saintly person who is famed throughout the land for the beauty of her thoughts. indeed, such is her fame that she is often called wisdom. shortly before you arrive, as a dutiful preparation for your visit, you read some accounts of this person’s beauty. you read witness reports like the following: … she is more beautiful than the sun, and excels every constellation of the stars. compared to light, she takes precedence; for that, indeed, night supplants, but wickedness prevails not over wisdom. indeed, she reaches from end to end mightily and governs all things well. her i loved and sought after from my youth; i sought to take her for my bride and was enamoured of her beauty. religious studies, page of f cambridge university press doi: . /s another writer is also full of praise: in her there is a light i love, and a food, and a kind of embrace when i love her – a light, voice, odour, food, embrace of my inner man, where my soul is floodlit with light which space cannot contain, where there is sound that time cannot seize, where there is a perfume which no breeze disperses, where there is a taste for food no amount of eating can lessen, and where there is a bond of union no satiety can part. the same writer in a very famous passage declares: late have i loved you, beauty so old and so new: late have i loved you … . you called and cried out loud and shattered my deafness. you were fragrant, and i drew in my breath and now pant after you. i tasted you, and i feel but hunger and thirst for you. you touched me, and now i am set on fire to attain the peace which is yours. you read in the divine names: ‘and they name her beautiful since she is the all- beautiful and the beautiful beyond all. she is forever so, unvaryingly, un- changeably so … . she is the superabundant source in herself of the beauty of every beautiful thing.’ there are numerous other references to her beauty, although you note that recent writings about this person concentrate more on her possession of knowledge and power. this, you find, a little disappointing. having found such wonderful promises about this person, you are understand- ably keen to meet her face to face. the time comes and with infinite grace and gentleness, she approaches. she is so beautiful that you find yourself feeling foolish for finding anything else beautiful before. you say to yourself: ‘this is beauty – sheer, utter, unadulterated beauty. anything else is only a pale reflection of this.’ being a philosopher, however, you are keen to know her thoughts. she is famed for the beauty of her reflections, her contemplations, the wonderful stories she can tell. sitting before her, she tells stories to you of such sheer ingenuity, originality, style and beauty that you find yourself feeling an awesome inspiration. sometimes the stories are comfortable, relaxing – you feel intensely calm, meditative. in other stories – more sublime – you feel as if confronted by the terror of a mountain or an infinite abyss. but behind the awe-inspiring terror, you feel an all-encompassing love such as a parent would feel to its offspring, but immeasurably more intense. you ask her: ‘are these your thoughts, beautiful one, or are they copied from elsewhere?’. she replies, ‘yes, they are mine. there is no other but myself who is the source and originator of these stories of great beauty. i copy from nowhere, but look only inward at the infinite reserves of my own contemplations.’ you think to yourself: ‘her thoughts are beautiful, so wonderful, so inspiring. they are noble, grandiloquent – you can hardly find words adequate to express their wonderfulness. and she is their originator!’ you remember the lines of another worshipper of this person: she takes absolutely nothing from any other source, whence it might either frame a model in itself, or make its creatures what they are; while the mere human artist is m a r k i a n t h o m a s r o b s o n wholly unable to conceive in his imagination any bodily thing, except what he has in some way learned from external objects … . and again the same author expresses her originality like this: ‘it is equally certain that whatever she created, she created through nothing other than herself; and whatever she created, she created through her own most intimate expression’. ‘let me tell you another of my stories’, she says gracefully, with a voice so utterly sweet and gentle. you settle down thirsting for another beautiful story. you love this exploration of her mind. however, your eagerness turns sour as her new words unfold. you find yourself feeling uncomfortable, then feeling physically sick. the story she tells you is an incredibly detailed tale of the rape and murder of a child. nothing is left to the imagination. the story is so detailed, so minute in its descriptions that it is as if the terrible events are unfolding before your very eyes. it is a story of such ugliness that you are appalled. then, despite your protestations, she launches into a story of how hitler conquers europe, takes his murderous policies all over the planet and then establishes a galactic empire that takes never-ending, sadistic delight in killing the innocent. the story exactly parallels what the real world would be like were this possibility to have been actualized. she tells another tale. this time she tells you a narrative whose horror is so acute, so perverse that no mere human mind would have been able to originate such filth. ‘beautiful one’, you respond (you find this epithet less appropriate now), ‘again i ask ‘‘are these stories part of yourself, or do you look outwardly at another source?’’ ’. ‘my child, they are part of me and i have other tales of such perversity, such dreadfulness, of such moral depravity that your mere finite mind could not even to begin to comprehend the sheer horror of their ugliness. i have possessed all these stories for all eternity. never once has any part of them been lost from my consciousness. i have contemplated their appalling nature for all time. even as i see you now i am vividly aware of the story of you being tortured to death on a rack. this story is, also, an eternal part of who i am.’ as you leave, you recall augustine’s words about her beauty, her peace, her fragrance, but with the taste of bile still bitter in your mouth and your mind reeling at the ugliness of the stories she uttered, you find these words very hard to believe. what have i tried to convey in this parable? i have tried to alert the reader to a problem i think exists. i have presented the problem in a dramatic and deliberately shocking way. it seems to me that many of us are so used to the idea of possible worlds that we employ the idea without much perception of its hidden, theo- logical dangers. let me draw attention to the central ideas i tried to convey in the parable: first, the stories god tells (the woman, of course, represents god) are meant to be the equivalent of possible worlds or, to put it another way, they are the possible worlds and the beauty of god possible world books that god possesses as a part of his contemplations. in this model of god’s understanding, god eternally contemplates a whole host of possible worlds. these worlds are understood to be maximal, determinate, and represent every possibility. basically, the idea is that god knows what his creation will be like by looking toward these possible worlds. he examines these as a kind of prelude to creation. second, these worlds are usually understood (in best christian platonist fashion) to be part of god. unlike the demiurge, god looks inwards at himself to find these possible worlds, and so his aseity is preserved. he relies on no other thing but himself in order to effect the creative act. third, the worlds are eternal. they are eternal parts of the divine being. my argument is simple. given this understanding of possibility, i.e., that god possesses from all eternity ugly, depraved, terrible stories representing every ugly possibility, then, how can he be utterly and completely beautiful? for the rest of this paper i will consider what a possible-worlds’ theorist could offer in defence of the claim that his model of the divine mind does not com- promise the divine beauty. i will consider the following replies: ( ) possible stories are neither ugly nor beautiful – only if they become actual can they be ugly or beautiful. ( ) god’s beauty consists of a union of truth and goodness. god has to know the truth of what is possible if he is to be beautiful, even if those truths are themselves horrible. his goodness means that he looks upon these horrible truths with a healthy hatred. ( ) the conception of beauty i am working with is not up to scratch since it is sentimental. true, unsentimental beauty can cope with ugliness and defeat it, so that the narrative is made beautiful. ( ) god’s beliefs are so wholly unlike ours that my parable fails to tell the truth of what god’s cognizance of stories of possible events is like. let us look at the first reply. here the leibnizean claims that only if the stories become actual, can they be understood to be ugly or beautiful. he might begin his argument by saying that this is, for example, true of the moral goodness or evil of possible actions. if i contemplate the possible evil of a particular action (and, on that basis, reject it) i have not been morally compromised. merely entertaining the possibility of an evil action does not affect me morally. to put it another way, a possible evil action is only really evil if it is actualized; if, that is, it becomes real. possible evil worlds are only evil if they come to be. arguing in a parallel way, the leibnizean claims that stories of possible ugliness are only really ugly if they are actualized – if, that is, they become real. the same, of course, would be true of beautiful stories. i do not think that this reply works. we might accept that mere possibilities cannot be evil or good, but we do say of stories that they are beautiful or ugly. when i say of a story that it is ugly i do not just mean that if the story were m a r k i a n t h o m a s r o b s o n to become true it would be ugly; i mean the story itself is ugly regardless of whether or not the events it describes become real. to claim that stories them- selves – regardless of their actualization – cannot be aesthetically judged would surely be an outrageous claim. now the leibnizean might reply that a more nuanced understanding of what it is for a story to be ugly can save the day. he might say that, strictly speaking, no story is in itself ugly or beautiful – it is only the telling of the story that deserves aesthetic approbation or disapprobation. here the leibnizean separates content from form and claims content is aesthetically neutral, while form (the way the story is told) is amenable to aesthetic judgement. doubtless, there is something in this claim – the drab and the mundane can be transformed by the form, but i doubt whether this kind of transformation is always possible. if it is always possible, then, all stories can be beautiful if they are told well. the form always has the final word. this is hard to believe. let us return to our parable. imagine wisdom after seeing your reaction to the child rape and murder story assures you with the words, ‘but haven’t i told it with flair and charm and an eye for detail?’. i do not think you would be convinced. i think that the content is just intrinsically ugly regardless of the form in which it is conveyed. what is true for a child rape and murder seems even more true of other such horrors as the story of a possible galactic holocaust. in any case, exactly what form is god supposed to use? according to the typical leibnizean, these stories must represent exactly what the actual event would be like in all its detail. i tried to show this point in the parable when i mentioned the minute detail of the story that wisdom tells. the story i said ‘exactly parallels what the real world would be like were this possibility to be actualized’. there can be no extraneous, technical flourishes on god’s part, no blurred, impressionistic representations. he must, it seems, faithfully copy for all eternity what the rapist would do if the rapist were to rape and murder a child. here, it seems, the content masters the form and completely overwhelms it. of course, many great works of art represent scenes of great ugliness. there are, for example, picasso’s guernica, and matthias grünewald’s isenheim altarpiece. these are indeed great works of art but it is hard to believe that anyone considers them beautiful in themselves. indeed, we think of them as ugly, but their intrinsic ugliness is mitigated by the painter’s skill in the mastery of form. we, also, value such great works because of the way they make us think of the pervasiveness of suffering in the world. it is worth recalling here that the leibnizean has to show that there is no vestige of ugliness whatsoever in god’s stories of possible events. any ugliness, no matter how minuscule, will sully the purity of the divine beauty. the ugliness of wisdom’s story of child rape may be softened by her absolute hatred of it, but is all the ugliness completely obliterated? i do not think so. let us summarize our conclusions. ( ) stories do not have to wait to be actua- lized before they are ugly. i take this point to be obvious. ( ) form may help to possible worlds and the beauty of god transform content, but some content is so ugly that no amount of amelioration by form can remove all the horror. in any case, i have argued that god must faithfully represent the horror. he must obey the dictates of the rapist’s possible actions. god cannot transform the actual content; the narrative must be a faithful copy of the action. it is now time to look at another, perhaps more promising line of reply. god’s beauty does not stand alone says the leibnizean – it is a union of truth and goodness. the argument might go something like this: god’s beauty contains all truth. because he contains all truth he must contain all the truths about what is possible. it is an eternal truth about possibility that if free agents were to exist then some of them might freely choose to commit rape and murder. god sees these agents and he sees their possible acts. his goodness means that he sees that this possibility, if made actual, would be a great evil. he uses this knowledge to find the truth of what an actual world would be like. he weighs these matters employing his moral perfection to create the world which is reported in genesis as being ‘good’. as part of the magnificent omniscience and moral perfection of god, even these terrible stories are involved in his beauty. the leibnizean might put it in this way: it is a perfection or part of god’s perfection that he knows what the rapist and the murderer might do. imagine a god at a loss to know what the rapist might do next – such a god would be always being caught out by creation! he would not appear to be perfect – he would be a being who might well be unworthy of our worship. so we need these stories – horrible as they are – if we are to worship one who properly deserves our praise. i think that this reply fails. first, is it really part of perfection to be the ultimate ground of these stories? i have no problem with a god who looks outwardly at the actual rapist and murderer and knows their possibilities, their capacities, their desires, their thoughts – indeed, just like the leibnizean, i want him to know what these people might possibly do. this is a god who sees possible evil in creation itself. such a god sees ugliness (and moral imperfection) outside of himself. but in the leibnizean picture, we have a god who before creation is even actual, looks inside himself and sees the rapist performing his possible actions. such sights or such stories would be ugly, and their ugliness would not be exterior to the divine being but be a part of his very essence. this is bad enough, but for the leibnizean, these stories continue to inhabit god for all eternity. as i tried to suggest in the parable, presumably there are darker, more perverse, more ugly stories inside the divine being – whole worlds of sadism, whole worlds of rape, whole worlds of holocausts. second, even if the leibnizean were to show that god’s being the ultimate ground of all evil is not morally compromising, it would not answer the principal charge being pursued in this paper that it is aesthetically compromising. according to the typical leibnizean, the realm of possibility is a set of discrete worlds or m a r k i a n t h o m a s r o b s o n world books. if it is possible that a world of child rape and murder can exist or worlds of galactic holocausts, then, these are individual worlds or stories in the mind of god. they do not form a uniting part of some aggrandizing, beautiful vision; instead, they seem to be ruinous blots on the landscape of the divine contemplations. being individual worlds representing what is possible in that individual world, they are units of ugliness, individual paintings, if you will. we may try to put them in a fancy frame, but the ugliness of their content is still present. some parts of god, it appears, must be ugly. it does not seem to me that we can integrate these ugly, possible worlds together to make some kind of beautiful whole. let me summarize the argument: we might be able to show why it is not morally objectionable for god to be – in some way – the ground of the possible actions of a possible rapist, but we cannot make the rapist’s possible actions beautiful, even by trying to make these possible actions part of some grander scheme. the rapist’s possible actions are ugly in themselves. god’s stories of what possible rapists might do must carefully represent each part of the rapist’s actions. how can these kinds of story be made beautiful? now the leibnizean might put his objection in a different way. he might say, ‘do we want god to be ignorant of what is possible? surely the resultant blanks, the lacunas in god’s mind would be a serious lack – a kind of ugliness. knowledge is more beautiful than ignorance, even if that knowledge is knowledge of ugly things.’ the question is this: does denying god access to knowledge of possible worlds leave him with an ugly ignorance? this entirely depends upon whether one thinks that there is an ignorance being introduced into the divine being. as open theists often say, their denial that god does not know what free agents are going to do is not necessarily a limitation on omniscience. more correctly they are putting forward a thesis about ontology, or what is there. similarly, if possible worlds do not exist in any shape or form, then there is no denial of divine omniscience if we say that god ‘cannot’ know them. such things as possible worlds may be just unpleasant figments of the philosophical imagination. if they are really just figments, then, no ignorance is introduced into the divine being. now let us consider another objection to our argument. i might be accused of a having an incomplete notion of beauty – perhaps the notion of beauty that is implicit in this essay is a prettified, cosy kind of beauty. beauty, properly understood, is not sentimental. as jeremy begbie claims in an excellent recent essay, beauty is sometimes unveiled after a period of darkness. he says that the darkness or ugliness of holy saturday is a part of the drama of the eventually vindicating easter story. i agree with begbie. i agree that the transforming power of god, especially in the cross, can defeat darkness, and that the overall story that christianity offers is a positive, victorious one, despite the horrors. god will defeat darkness, and that defeat of darkness will be an unsentimental beauty, one that looks evil in the face, but eventually defeats it. possible worlds and the beauty of god unfortunately, however, this is not the vision god will have in some of his possible worlds, the stories which are an eternal part of himself, the stories that he eternally has as part of his very essence. every possibility is represented in these worlds. we might agree, for the sake of argument, that the only worlds god would actualize would be those worlds in which he redeems all and defeats the ugliness, and his triumph is seen as an unsentimental, beauteous victory. but what of those darker worlds which god would never actualize? what of those possible worlds where he does not redeem the victim and free the enslaved? these worlds – which god would never actualize – are, according to our typical leibnizean, present in the mind of god. they are possible, it is said, because they are internally self-consistent sets of events. consequently, there will be myriads of possible world stories where sadistic torture is eternal, and injustice reigns for all time, where the child murderer carries on delighting in his perver- sion. we can delight in the fact that god turns his face away from these worlds in the sense that he does not allow them to be actualized, but nevertheless they are still there as possible stories in god’s mind. they represent the possible ways worlds would be if those worlds were to be unredeemed. they would be ugly worlds without a trace of the divine victory. finally we turn to the last objection to the idea that god’s stories of possible events compromises the divine beauty. linda zagzebski discusses william alston’s claim that we must not think of god literally having beliefs. beliefs are units or chunks of information, and it seems wrong to think of god’s access to knowledge being parcelled into the sub-units or chunks that beliefs provide. finite sentient agents, of course, have to believe in a multiplicity of truths, some about this and some about that. our access to reality is, it seems, irredeemably chunky. alston’s suggestion, which is inspired by aquinas, is that god’s access to knowledge is radically different. according to this claim, all is seen in one undifferentiated vision. so instead of propositional units (which are for us the mediating objects of beliefs), god sees all truth directly in one grand vista. linda zagzebski is sympathetic to alston’s account. in her discussion she combines his idea that god’s access to the truth is not via the mediating units of belief with the thomist notion that god’s primary vision is himself. she writes: primarily and essentially god knows only himself. to know anything else would be to focus the divine gaze on the imperfect. but in his simple and direct intuition of his own essence, god knows secondarily everything else. this is because god’s essence contains exemplars of the infinitely many ways his essence can be represented in finite reality: ‘god knows himself as primarily and essentially known, whereas he knows other things as seen in his essence. to understand this idea and to explain how god is able to know the con- tingencies of the created world even though his conception is of himself, zagzebski suggests using an analogy from the act of human vision. imagine, she m a r k i a n t h o m a s r o b s o n says, seeing a young man’s face. this is the primary act of seeing. it is a single act of vision – one sweeping influx of visual information. now, she explains, pri- mary acts of vision can have different secondary objects as well. let us suppose that we see the mother’s features through our primary act of seeing the young man’s face. it is a familiar enough experience. this secondary object is, zagzebski notes, a mere accidental property of the first vision. given a visually different mother would mean you ‘see’ another secondary object. in other words, it is not an essential part of the primary vision that the secondary object is what it is. now she applies this analogy to god’s knowledge. god sees only himself. his primary vision is his own beautiful perfection. secondary objects of the divine primary vision are different depending upon what the world is like. as we have said, these secondary objects are merely accidental, and because of this they are able to reflect the contingencies of the actual world. just as visually different mothers could be ‘seen’ even though the face of the son remains the same, god sees different worlds even though his primary vision is necessarily identical. now we are in a position to explain how an objection to my account could go. the objector argues that god’s vision is only himself. this vision is, of course, pure, unadulterated beauty. stories of possible rapes and murder (ugly stories) are known only ‘through’ this vision of unalloyed beauty. these are merely the secondary objects of the divine contemplation; primarily his vision is of himself. an objector could argue that such an account saves god from the compromise of ugliness. after all, god only sees the beauty of the divine perfection. does this account work as an objection to my argument? first, i have to admit to being attracted to the thomist understanding that god’s access to the truth of things is direct and undifferentiated. it does not appear to me to be plausible to understand god’s knowledge as being parcelled up into units. alston’s account seems to avoid an implausible and unwelcome anthropomorphism in our understanding of divine knowledge. zagzebski’s addition that god knows the (accidental) vagaries and imperfections of this world through the primary vision of himself is ingenious and thought-provoking. i do not, however, think it can be used to avoid the charge that god’s knowledge of the possible compromises his beauty. the crucial difference is that god’s vision of the possible is not, ac- cording to the leibnizean, a merely accidental feature of the divine contem- plation. orthodox leibnizeans are committed to the necessity of the possible. god’s knowledge of the possible is not, therefore, a mere accidental object of the divine vision. god, according to the leibnizean, sees all the possibilities that there are, and he sees them as necessary objects of his contemplation. given the necessary nature of god’s musings concerning the possible, it is hard to understand in what sense they could be mere secondary objects of the divine vision. certainly we can accept that what becomes actual is a contingent matter – perhaps zagzebski’s idea might be used here to avoid the charge that god’s everlasting knowledge of actual rapes compromises the divine beauty. but possible worlds and the beauty of god what is possible is not contingently possible – it is a necessary part of the divine understanding. it appears, then, that ugly stories of the most appalling kind would be an integral, essential part of the divine self and so ruin the beauty of the divine vision. as i say, i accept that god’s knowledge is radically unlike ours. his knowledge may not be divided like ours into stories and narratives (chunks of information). the idea that god knows stories may well be just an accommodation to meet the inadequacies of our finite, limited understanding. nevertheless it is hard to accept that what to us is appallingly ugly can be converted into beauty by its being subsumed into divine undifferentiated vision. recall that god’s vision of the possible must exactly parallel the actual act which could emerge. god’s vision cannot be blurred – any subsuming must not allow the horrific visions he sees to be changed in any way. the leibnizean wants god to see exactly what might happen. these visions are part of who god is. i think that such an understanding of god necessarily fills the divine beauty with ugliness. conclusion it seems to me, then, that if we take the typical possible-worlds approach where god contemplates for all eternity every possibility, we have a problem. some parts of god will be ugly. as far as i can see, there are four broad solutions to the problem. ( ) admit that god is not beautiful, or say that god is only beautiful in part. as i mentioned in a note to this essay, there is that strand of theological thinking that reckons that our (beautiful) god rose out of a more primeval ground; he is the god that arose when the ground rejected the ugliness in himself. i fear that many philosophers and theologians would rather this happen than have one single question mark be put against what their view is of the comprehensiveness of the divine omniscience. ( ) say that possible worlds are outside of god. he does not look within at the ugliness of possible worlds, but outwardly on an exterior necessarily existing ugliness. this compromises the divine aseity, but seems to preserve the divine beauty. because it compromises god’s aseity, i reject this solution to the problem. the price the solution demands is too high. ( ) claim that there are no possible worlds in which god does not decide to defeat and transform evil into an unsentimental beauty. there are no darker, unredeemed possible worlds or possible stories. m a r k i a n t h o m a s r o b s o n one problem with that is that it would result in making it a necessary truth that god redeems evil. we are all used to hearing the dictum that if something is true in every possible world, then, it is a necessary truth. so if it is true that god defeats evil in every possible world, then, it is a necessary truth that god redeems evil. this seems to limit the divine freedom and what we always suppose is the sheer, gratuitous nature of his grace. another problem is that possible worlds are meant to be, in most possible-world semantics, the ground of our declarative statements; they are, adams says, the ‘fundamental objects of logic’. when i talk of unredeemed worlds i seem to be talking of something. the possible world semanticist says that i am talking about possible unredeemed worlds. ( ) reject possible worlds completely and say with arnauld that there are no merely possible things. in correspondence with leibniz, arnauld rejects talk of possible worlds and possible things: … i acknowledge in good faith that i have no idea of substances purely possible, that is to say, which god will never create. i am inclined to think that these are chimeras which we construct and that whatever we call possible substances, pure possibilities are nothing else than the omnipotence of god who, being a pure act, does not allow of these being a possibility in him. possibilities, however, may be conceived of in the natures he has created, for, not being of the same essence throughout, they are necessarily composites of power and action. i can, therefore, think of them as possibilities. i can also do the same with an infinity of modifications which are within the power of these created natures, such as are the thoughts of intelligent beings, and the forms of extended substance. but i am very much mistaken if there is anyone who will venture to say that he has an idea of a possible substance as pure possibility … . i am convinced that, although there is so much talk of these substances which are pure possibilities, they are, nevertheless, always conceived of only under the idea of those which god has actually created. we seem, therefore, able to say that outside of the things which god has created, or must create, there is no negative possibility but only an active and infinite power. i could say much in defence of arnauld’s claim, but now is not the time. let us leave the argument with these questions: have we got our emphasis right in modern philosophical theology with our primary preoccupation with notions of omniscience and omnipotence? have we lost sight of the divine beauty amid the endless discussions about power and knowledge? it is my view that a rededica- tion to the beauty of the divine being might well help us to re-think what it means for god to be maximally powerful and knowledgeable. notes . in questioning possible worlds i join the growing band of those who reject the notion that god employs possible worlds in the processes of creation. see david burrell freedom and faith in three traditions (notre dame in: notre dame press, ), – ; idem ‘creation and ‘‘actualism’’: the dialectical possible worlds and the beauty of god dimension of philosophical theology’, in david burrell faith and freedom (oxford: blackwell publishing, ), – ; james ross thought and world (notre dame in: notre dame press, ), – . barry miller’s thoughts tend in a similar direction. he rejects that common preconception that before their actuality individuals can be referred to; barry miller the fullness of being (notre dame in: notre dame press, ), – . see also my ontology and providence in creation: taking ex nihilo seriously (london: continuum, ). . wisdom of solomon, . – . (new american bible). . augustine confessions, book x, vi, (oxford: oxford university press, ), (translation slightly adapted). to keep with the traditional references to wisdom as female i have slightly adapted some translations both here and below. . ibid., book x, xxvii, , . . pseudo-dionysius: the complete works (london: classics of western spirituality, ), – (translation slightly adapted); quoted in patrick sherry spirit and beauty (london: scm press, ), . . patrick sherry and richard harries are just two of the scholars who have drawn attention to the neglect of the beauty of god in recent times. see sherry spirit and beauty, – ; richard harries art and the beauty of god (london: continuum, ), – . see also edward oakes’s essay ‘the apologetics of beauty’, where he looks at how the ugly is often glorified in modern art and culture. he tries to show (drawing upon the ideas of von balthasar as his chief inspiration) how the idea of beauty must be an integral part of the christian witness; edward oakes ‘the apologetics of beauty’, in d. treier, m. husbands, & r. lundin (eds) the beauty of god (downers grove il: intervarsity press, ), – . . anselm monologium, ch. (la salle il: open court publishing, ), (translation slightly adapted). . ibid., ch. , (translation slightly adapted). . we need not enter the debate about whether possibility is best understood as maximally consistent sets of propositions, or whether it is best seen as sets of states of affairs, or, indeed, whether propositions just are states of affairs. if the reader is sceptical about possibility being understood to be propositional in content, he or she can adjust my parable so that god shows states of affairs to his audience. whatever one chooses as one’s preferred way of understanding possibility, some of those possibilities will be ugly – if, that is, we accept the possible-worlds account of the divine understanding. . it might be claimed that my complaint is not against possible worlds, but any comprehensive account of god’s omniscience. i have argued elsewhere that rejecting possible worlds does not compromise divine omniscience. see robson ontology and providence in creation, – . possible worlds are especially iniquitous in my view since they are discrete, eternal, necessary, determinate, and are seen as part of the divine mind. i am not so sure that writers like augustine (who undoubtedly believed in god’s omniscience) would have been ready to accept possible worlds. most writers (up to leibniz) seemed content that god had ideas of humanity and equinity, rather than knowledge of individual essences like socrates and bucephalus. . the most standard formalization of modal logic (s ) accepts that possibility is a matter of necessity; that is to say, whatever is possible is possible necessarily. so whatever is possible, will continue to be possible for all eternity. even before the world existed and there was only god, then, murder, rape, torture, and all other moral horrors were possible. these possible horrors will continue, if we accept the possible-worlds’ picture, to haunt reality forever. . not all the ugly worlds that god would contemplate would be evil; some would just be horrible to look at, or just entirely without rhyme or reason. consider the world whose only constituent is a snarling, ugly face inscribed on the surface of some rank sewage. presumably (if there are possible worlds) this world (or its story) is present in the divine consciousness for all eternity. . for ease, i will refer to the possible-worlds’ theorist as a ‘leibnizean’ in honour of the chief inspiration of this way of understanding the divine mind. . there are some complex issues here. some people fantasize about rape and murder. they do not want these things to become actual, however. they realize that actualization would be morally terrible: real people would get hurt. so they entertain certain evil possibilities without wanting them to become actual. however, most would accept that such fantasies are morally compromising. the line between fantasy and mere contemplation of an evil is quite hard to draw. for ease of presentation, i ignore this difficulty. m a r k i a n t h o m a s r o b s o n . the story would not even have to be told to anyone for it to be ugly. even if wisdom had kept her stories to herself, they would still have been in her mind – a kind of secret stain! perhaps these secret stories would be even more worrying. . i deliberately use the word ‘copy’. part of my discomfort with possible-world accounts of the divine mind is what i see as its consequence that god inevitably has to yield to the eternal dictates of possible rapists and murderers. it is as if there are independent currents of sin swirling in the divine consciousness. (the number of these independent currents is infinitely multiplied by those who believe in middle knowledge.) this independence of the possible from the divine will is, of course, acknowledged by the leibnizean. leibniz himself explicitly rejected the idea proposed by descartes that the logical laws themselves were subject to the divine will. leibniz, in contrast, claimed that the logical laws depend upon the divine understanding, but not upon his will. i have no wish to endorse descartes’ universal possibilism. i think that the logical laws (say, for example, the law of non-contradiction) is somehow embedded in the divine being, but this acknowledgement of the existence of this law does not legitimize the inference that there are whole, determinate, possible worlds in the divine mind which already obey it. . another way the leibnizean might try to ameliorate the ugliness of god’s stories is to say that god’s knowledge of possibilities are not so much stories, but sets of truths or sets of propositions. so god knows the truth ‘if leatherface were to work in an abattoir, he would acquire an unhealthy interest in chainsaws’. god merely knowing sets of truths might seem less ugly. a proposition, it might be argued, is just a proposition – it is aesthetically neutral. i am not so sure – the set of possible truths about a possible galactic holocaust seems ugly and seems to constitute a story, a narrative, a way things might go. on god only knowing truths see william lane craig time and eternity: exploring god’s relationship to time (wheaton il: crossway books, ), – . . david brown in his commentary on grünewald’s isenheim altarpiece says that originally the painting was intended for a hospital ‘which cared for those suffering from a particularly ravaging illness that produced gangrene, boils, blackened skin and muscular spasms’. those suffering would be able to find some consolation in christ sharing their pain. see david brown tradition and imagination (oxford: oxford university press, ), – . . of course, were all the ugliness eliminated by its being looked upon with hatred, there would no longer be much left to look upon! . it is also worth recalling that when picasso painted guernica he was reacting to an event outside of himself. he wanted to show the ugliness of what had happened. but god in his possible stories is not reacting to things outside of himself; he is looking inwardly at the contents of his own mind. if, then, god hates the story of child rape and murder (which surely he does), is he hating a part of himself? do we have to agree with those theologians who have speculated about the existence of a divine darkness? if so, we must accept that god is not wholly beautiful. he contains ugliness as well as beauty. . richard harries argues for something like this in art and the beauty of god, – . . there are some complex issues here. i suspect that a leibnizean would try to remove any taint of moral imperfection on god’s part by trying to show that evil can only be weakly actualized by god. he is, therefore, evil’s weak grounding. another way out is to claim that evil has no grounding at all. this was leibniz’s preferred option. see gottfried leibniz theodicy (la salle il: open court press, ), – . nevertheless, according to leibniz, god still can see the story of evil’s unfolding in his understanding. leibniz says, ‘where shall we find the source of evil? the answer is, that it must be sought in the ideal nature of the creature, in so far as this nature is contained in the eternal verities which are in the understanding of god, independently of his will … . and [in the divine understanding] is found not only the primitive form of good, but also the origin of evil’ ( – ). there is no time to pursue these claims here, but i find the idea that evil’s ontological status is somehow identical with a lack or privation to be deeply implausible. certainly evil’s existence can be explained by a lack or deficiency, but to identify it literally as a lack is to say something deeply puzzling. however, even if these replies were successful in rebutting the claim that god is the ultimate eternal ground of evil, it would not answer the central charge that having these stories as a part of god’s being is compromising to the beauty of god. as we have just read, leibniz says that part of god’s understanding contains the ‘origin of evil’ – i.e. in the eternal deficiency of the possible creature in the mind of god. possible worlds and the beauty of god . see, for example, g. boyd ‘the open theism view’, in j. beilby & p. eddy (eds) divine foreknowledge (downers grove il: intervarsity press, ), – . . i have tried to avoid this charge by having wisdom in the parable tell some awe-inspiring, even terrifying stories. i do not think that god’s beauty is safe or tamed. (as c. s. lewis so rightly said, aslan is not a tame lion!) i think that the terrifying can be beautiful. a story of child rape and murder, on the other hand, is terrifying and ugly – it is certainly not sublime! on the relationship between the sublime and the beautiful, see jeremy begbie ‘created beauty: j. s. bach and the arts’, in treier, husbands, & lundin the beauty of god, – . . jeremy begbie ‘beauty, sentimentality and the arts’, in treier, husbands, & lundin the beauty of god, – . . begbie talks about seeing the easter events in two ways. in one view we see the events in the light of the resurrection, as the crucified lord eventually being vindicated. in another view we live through the trauma of the uncertainty of this transformation – as the disciples lived with the uncertainty of easter saturday. begbie is very insistent (and i think rightly so) that god’s eventual vindication of the crucified lord is not a vindication of the moral horror of crucifixion. see begbie, ‘beauty, sentimentality and the arts’, . we cannot fit horror into a pattern which makes the horror itself beautiful. another important point: any talk of god defeating evil must also look at the problem of hell where evil (and ugliness) seems eternalized. on this see hans urs von balthasar dare we hope ‘that all men will be saved’? (san francisco ca: ignatius press, ). . there is a problem here. in what sense are possible worlds possible, if they could never be actualized? in what sense is something possible if it cannot (possibly) ever be or ever have been? and yet we hear some philosophers, following the inspiration of alvin plantinga the nature of necessity (oxford: oxford university press, ), – , saying that there are possible worlds that even god cannot actualize. william lane craig, for example, claims that god’s free knowledge ranges over all possible worlds, but then, confronted with the counterfactuals of creaturely freedom, god finds that there are some worlds he cannot create, or which are not ‘feasible’ for him; william lane craig the only wise god: the compatibility of divine foreknowledge and human freedom (eugene or: wipf & stock publishers), – , and idem ‘the middle-knowledge view’, in beilby & eddy divine foreknowledge, – , – . i am always at a loss to understand how worlds are possible if it is absolutely impossible for the ground of all being to actualize them? it is almost as if these unactualizable creatures and worlds defy god before they even exist. thus again, according to the leibnizean, there are whole swathes of god utterly defiant to the divine wishes. this defiance remains stubbornly recalcitrant for all eternity. . linda zagzebski the dilemma of freedom and foreknowledge (oxford: oxford university press, ), . . ibid. . . ibid. – . . again, we need to note that orthodox leibnizeans commit themselves to s . . richard creel in divine impassibility (cambridge: cambridge university press, ) puts forward the idea that alongside god there is a plenum representing every possibility. . i would agree, however, with begbie that one cannot beautify horror by making it part of some grander narrative. so, even if the only worlds which are possible are those in which god defeats evil (and so the whole is good), there will still be areas of local ugliness. this local ugliness must be represented in the possible worlds that god scrutinizes prior to creation. . robert adams leibniz: determinist, theist, idealist (oxford: oxford university press, ), . . the problem would be even worse for someone like alvin plantinga who accepts impossible worlds as part of his ontology; plantinga the nature of necessity, . so even if we were to say that these worlds are somehow logically impossible, their ugliness as impossible worlds would continue to infect the divine being. . gottfried leibniz, correspondence with arnauld (la salle il: open court publishing, ), . . see robson ontology and providence in creation, – . . acknowledgements: fr andrew downie provided some very helpful comments on the paper and helped clarify some vital issues; david burrell and john o’callaghan read the paper and encouraged me to send it for publication; david brown also read an earlier version of the paper, as did medi volpe. i am grateful to all of them for their time and help. m a r k i a n t h o m a s r o b s o n soil, , – , https://doi.org/ . /soil- - - © author(s) . this work is distributed under the creative commons attribution . license. soil soil lacquer peel do-it-yourself: simply capturing beauty cathelijne r. stoof , jasper h. j. candel , laszlo a. g. m. van der wal , and gert peek ,* soil geography and landscape group, wageningen university, p.o. box , aa wageningen, the netherlands *retired correspondence: cathelijne r. stoof (cathelijne.stoof@wur.nl) received: august – discussion started: november revised: march – accepted: april – published: july abstract. visualization can greatly benefit understanding of concepts and processes, which in soil science and geology can be done using real-life snapshots of soils and sediments in lacquer peels and glue peels. while it may seem complicated, anyone can make such a soil peel for use in classrooms, public places, homes, and offices for teaching, outreach, decoration, and awareness. technological development has considerably simplified the making of soil peels, but this methodological innovation has not been described in the literature. here, we report on a thoroughly tested and simple method for taking peels of sandy soils using readily available tools and materials. our method follows the main previously published steps of preparing a soil face, impregnating the soil face with a fixation agent in the field, extracting the resulting peel, and mounting it on a wooden panel. yet instead of using lacquers and thinning agents, we use strong though flexible contact adhesive (glue), which has the major advantage that it no longer requires use and mixing of toxic chemicals in the field or reinforcement of the peel to prevent breaking. moreover, the preservation potential is much higher than with the old method. this new twist to old methods makes creation of soil peels safer, simpler, and more successful, and thereby a true diy (do-it-yourself) activity. the resulting increased accessibility of making soil and sediment peels can benefit research, teaching, and science communication and can thereby bring the value and beauty of the ground below our feet to students, schools, policy makers, and the general public. introduction attention for soils is increasing around the world, in part due to strong initiatives on soil health (stott and moebius-clune, ; schindelbeck et al., ) and soil carbon ( ‰, mi- nasny et al., ), explicit articulation of how soils can help achieve the united nations sustainable development goals (keesstra et al., ; bouma and montanarella, ), and the recent united nations and iuss declarations of the inter- national year of soils (fao, ) and international decade of soils (iuss, ), respectively. the relevance of soils lies in the valuable beauty of soils: their multidisciplinary functions and benefits (brevik et al., ; dominati et al., ) and thereby their basis for life, in a world where soils are under threat (montanarella et al., ). capturing this beauty in monoliths or soil lacquer peels can bring soils to life for education and outreach (van baren and sombroek, ; lawrie and enman, ) or as a form of art (feller et al., ; breaker, ). while it is often thought to be quite challenging to capture soil profiles, a simple twist to an old method now makes the creation of soil peels a surprisingly simple do-it-yourself (diy) activity for scientists, educators, and the general public. soils and sediments can be fixated in two distinct ways: using peels and monoliths. both methods rely on impreg- nation of a soil face with a fixation agent (such as lacquer, resin, or glue), and their final product is typically mounted on a wall for study of undisturbed soil layers and character- istics, or simply for decoration. peels and monoliths are used to record and illustrate a range of different features in soils, such as differences between soil types, soil processes (e.g. weathering, gley, eluviation, and illuviation of clay, iron, and organic acids; fig. a), human impacts (fig. b), as well as biological activity such as plant rooting patterns, burrowing published by copernicus publications on behalf of the european geosciences union. c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty of soil fauna, and bioturbation. sedimentological and geo- logical processes can also be captured, such as cryoturbation, fluvial and aeolian layering (fig. c), frost wedges (fig. d), and faults (fig. e). and finally, peels can show the splen- did colours present in soils and sediments (fig. a–f). these natural snapshots of the subsurface are an effective way to inspire people about soils (megonigal et al., ) and geol- ogy, and are used around the world by museums, universities, schools, and institutes (table ) for teaching and outreach on the value of soils, the processes occurring in soils, effects of management, and other factors. interestingly, these soil pro- files are also used for testing knowledge of soils in job inter- views (jacqueline hannam, personal communication, ). peels and monoliths allow comparison of soils inside a class- room or museum environment without the need for students or visitors to travel, allowing exposure to a variety of soils in a short time and increasing accessibility of soil science to those with disabilities that prevent them from observing soil in situ. consequently, soil science education at wageningen university, the netherlands, strongly relies on a collection of ∼ lacquer peels for teaching purposes – despite the fact that this university is intentionally strategically located in an area where soil variability is high (van der haar et al., ) due to the range of distinct parent materials (glacial, peri- glacial, fluvial, aeolian, organic) and topography, and thus soil types within a km radius of the university. the main difference between making peels and monoliths is the location where the soil is impregnated with a fixing agent: a peel is impregnated in situ and extracted after dry- ing, while a monolith is an undisturbed soil block that is ex- tracted, transported, and then (repeatedly) impregnated in a laboratory (van baren and sombroek, ). monoliths can be created in any soil type, from sands to peats and heavy clays, but is rather time-consuming and requires specialized expertise in both the field and in the laboratory. their creation and recent methodological developments are rather well de- scribed in scientific journals (e.g. bouma, ; haddad et al., ; allaire and bochove, ; wessel et al., ; wright, ; donaldson and beck, ; barahona and iri- arte, ; fitzpatrick et al., ), presentations (fosberg, ), and reports (e.g. van baren and bomer, ; kiniry and neitsch, ; day, ; schuurman, ), as well as illustrated in online videos and tutorials (e.g. university of nebraska – lincoln, ; mueller, ). in contrast to soil monoliths, soil peels cannot be made from clay or peat soils since these are often too wet for impregnation in the field. peels are therefore limited to relatively coarse sediments that retain less water (lower water holding capacity) and allow more rapid impregnation of fixation agents (because of their higher hydraulic conductivity), which is required in field sit- uations. they thereby provide a rapid and accessible alter- native to soil monoliths. the lack-film method for creating peels was first developed in the s (hähnel, ; voigt, ; jahn, ). yet while the use of soil lacquer peels for scientific purposes has been recognized, e.g. to study sedi- mentological structures (bijkerk et al., ; van den berg et al., ), for palaeo-geochemical analysis (arnoldussen and van os, ), or archaeological applications (voigt and git- tins, ), the guidance available in the scientific literature is scattered, (out)dated, and/or incomplete. an english book that stands out is the comprehensive work by bouma ( ) that details the history of soil and sediment peels as well as a range of fixation agents used to make these peels. other published work includes a range of dutch- and german- language papers, popular-scientific articles and reports (vos et al., ; huisman, ; tno, ; van veen, ; hähnel, ; voigt, ), as well as a few older english- language articles (voigt and gittins, ; van baren and bomer, ; brown, ; hähnel, ). these publica- tions describe a range of materials used to make peels, most notably (nitrocellulose) lacquers, but also glue and resin. the main steps of the published methods for making peels are straightforward: a soil face was prepared under an angle and then (repeatedly) impregnated with a fixation agent, with the peel extracted after drying and then mounted on a wooden board. the challenge of the published methods lies in the fix- ation agents used years ago that required use of toxic sol- vents (e.g. acetone, toluene, xylene, thinner; bouma, ) in the field to achieve the right viscosity, increasing the risk of harming people and the environment. the resulting peel was rather fragile, and hence reinforcement with cheesecloth or bandage was required to prevent rupture of the dried lacquer peel (bouma, ). this fragility results in a lower preser- vation potential, which we have noted was especially chal- lenging when the soil peels were frequently handled when used for teaching. here we describe and illustrate a simpler, safer, more durable, and thereby more accessible approach to making soil lacquer peels, which relies on the use of glue available at hardware stores. while still synthetic, this glue is less harm- ful than the previous fixation agents, and its use straight out of the can reduces the spilling risk associated with the mixing of chemicals in the field. finally, this method can be easily deployed by those who have received no training. this new twist to an old method was developed by gert peek, a soil sci- ence educator at wageningen university who started teach- ing at what was then the laboratory for soil science and ge- ology at the landbouwhogeschool wageningen. as such, this method was used to collect both teaching material and data for msc theses (e.g. van der beek and ellenkamp, ) and to enthuse hundreds of students to get a podzol above their bed, through the organization of “soil profile weekends”. as we believe it is essential that scientific methods are preserved for future generations, we now report on the simple steps to capture the beauty of sandy soils for use in universities, schools, government buildings, museums, or simply at home. soil, , – , www.soil-journal.net/ / / / c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty figure . lacquer peels showing (a) paleo podzol (from below inset) covered by drift sands in which a younger podzol is formed, (b) plaggic anthrosol, (c) sedimentary layering, (d) frost wedge, (e) faulting, and (f) colourful sediments. insets show close-ups of damaged parts of the peel; white horizontal bars represent cm width; panels (a) through (e) are soil and sediment peels made in the netherlands (wageningen university collection, the netherlands); panel (f) is a sediment peel of the owl rock member of the chinle formation, chuska mountains, new mexico, usa (diné college collection, tsaile, arizona). the white scale bars represent cm. www.soil-journal.net/ / / / soil, , – , c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty table . example of museums, universities, schools, and institutes with preserved soil profile collections (soil monoliths and/or lacquer peels) in countries around the world. country institute source argentina universidad nacional de río cuarto, instituto nacional de tec- nología agropecuaria marcos angelini and alejandro becerra (personal communication, ) australia the university of sydney (australian technology park) ichsani wheeler (personal communication, ) austria university of vienna feigl ( ) belgium ku leuven etwie ( ), karen vancampenhout (personal communication, ) brazil universidade federal de lavras∗, universidade federal de roraima∗, universidade federal de santa maria∗, embrapa solos∗. ufrr ( ), ufla ( ), ufsm ( ), stephan mantel (personal commu- nication, ) canada university of alberta, university of british colombia, great lakes forestry center (ontario). krzic et al. ( ), natural resources canada ( ), liam heffernan (personal communication, ) colombia museo de suelos ciro molina garcés∗, museo de suelos instituto geográfico agustín codazzi∗. unal ( ), igac ( ) costa rica the tropical agricultural research and higher education center – catie∗ stephan mantel (personal communication, ) china china soil musem∗; the modern soil monolith exhibition center∗ giwsr ( ), isscas ( ) cuba instituto nacional de investigaciones de la caña de azúcar∗ stephan mantel (personal communication, ) ecuador ministerio de agricultura y ganadería. programa nacional de regionalización agraria (pronareg), museo de ciencias naturales∗ stephan mantel (personal communication, ) estonia soil museum estonian university of life sciences eesti maaülikol ( ) ethiopia national soil service project (dept. of watershed development and land use) stephan mantel (personal communication, ) germany halle university, university of hohenheim, technische universität münchen jahn ( ), steffen schweizer (personal communication, ) ghana soil research institute∗ stephan mantel (personal communication, ) india kerala forest research institute∗, tamil nadu agricultural university∗; university of agricultural sciences bangalore∗ kerala forest research institute ( ), stephan mantel (personal communication, ) italy jrc ispra alberto orgiazzi (personal communication, ) indonesia museum tanah (bogor soil museum)∗ ami ( ) japan natural museum of history and science; natural resource inven- tory museum; tsuchino-yakata, hokkaido keiko mori (personal communication, ) kenya kenya soil survey∗ stephan mantel (personal communication, ) mali laboratoire sol-eau-plantes∗ stephan mantel (personal communication, ) mexico instituto de recursos naturales (conabio)∗ stephan mantel (personal communication, ) soil, , – , www.soil-journal.net/ / / / c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty table . continued. country institute source netherlands world soil museum, wageningen university, vu university, rijk- suniversiteit groningen, has hogeschool, vhl university of ap- plied sciences, museonder, geologisch streekmuseum “de ijssel- vallei”, royal eijkelkamp, tno geological survey of the nether- lands, utrecht university isric ( b), de hoge veluwe ( ), geologisch streekmuseum “de ijsselvallei” ( ), martinius and van den berg ( ), nauta ( ), bernd andeweg, bram te brake, bram hoogendoorn, kim cohen, kirsten van der ploeg, richard kraaijvanger, sytze van heteren, wouter thijs (personal communication, ). nicaragua universidad nacional agraria∗ stephan mantel (personal communication, ) nigeria university of ibadan∗ stephan mantel (personal communication, ) pakistan soil survey of pakistan stephan mantel (personal communication, ) peru museo de suelos∗; instituto nacional de recursos naturales – inrena∗; universidad nacional de la amazonía peruana∗ fundacion ilam ( ), stephan mantel (personal communication, ) poland muzeum gleb (krakow university of agriculture) muzeum gleb ( ) philippines bureau of soils and water management∗ stephan mantel (personal communication, ) russia vasily dokuchaev museum of soil science, st petersburg; williams museum of soil and agriculture, moscow russian museums ( ), jetse stoorvogel (personal communication, ) spain universidad de murcia; universidad de granada; institut car- togràfic i geològic de catalunya um ( ), ugr ( ), lladós et al. ( ) taiwan national taiwan university∗; taiwan national research institute∗ chen ( ), churchman and landa ( ) thailand soil museum bangkok∗ thai museums database ( ) united arab emirates emirates soil museum emirates soil museum ( ) united king- dom cranfield university jacqueline hannam (personal communica- tion, ) united states of america california polytechnic state university, kansas state university, oklahoma state university, university of idaho, texas a&m, vir- ginia tech, west virginia university, university of georgia, smith- sonian’s national museum of natural history ( – ), cayuga nature center (ny), diné college (tsaile, az), american museum of natural history (ny) univeristy of idaho ( ), megonigal et al. ( ), pri ( ), american museum of natural history ( ), fitzpatrick et al. ( ), colby moorberg, christine mor- gan, jason warren, maurica fitzgibbons, meredith steele, micky ransom (personal communication, ) uzbekistan state research institute of soil science and agrochemistry ygk ( ), mirzokhid mirshadiev (per- sonal communication, ) venezuela universidad del zulia maracaiobo∗; universidad central de venezuela maracay∗ stephan mantel (personal communication, ) vietnam soils and fertilizers research institute∗ stephan mantel (personal communication, ) zimbabwe chemistry and soil research institute harare∗ stephan mantel (personal communication, ) ∗ institute that partnered with isric-world soil information to create a soil monolith collection (stephan mantel, personal communication, ). www.soil-journal.net/ / / / soil, , – , c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty taking the soil peel: six main steps . collect the required materials . . materials needed a range of materials is required to make a soil peel that can typically be found in any hardware store. table lists all ma- terials required to prepare the soil face (a spade, pruning scis- sors or garden shears, nail clippers, soil knife, ruler), to se- cure the soil (glue), to extract the peel (wooden board, spade, soil knife, pruning scissors or garden shears, garbage bag), to finish the lacquer peel (glue, notched trowel, stanley knife, nail clippers, scissors), and to mount it (hooks). in terms of personal gear, garden gloves and clothes that can get dirty are sufficient. any size can be chosen for the final size of the soil peel, and thus the size of the wooden board. soil pro- files at wageningen university are typically × cm. a wooden panel > mm thick (to prevent warping) is used for mounting – we use multiplex or medium density fibre board (mdf), though any wood can be chosen, depending on the desired aesthetics. . . characteristics of the glue the fixation agent used to impregnate the soil face is a liq- uid contact adhesive based on neoprene rubber. originally designed for shoe repairs that require two sides to be pressed together, this neoprene rubber contact adhesive works very well for making peels because it is flexible yet strong when dry. this flexibility is key for successful extraction of the peel from the soil face: glue that fully hardens when dry (like wood glue or glues used to impregnate monoliths in the lab) will break upon extraction and/or mounting of the peel. another benefit of this glue is that it does not shrink when drying, unlike the lacquer used for instance by häh- nel ( ). in the netherlands, neoprene rubber contact ad- hesive is sold as bisonkit universal (bolton adhesives, rot- terdam, the netherlands; bison international, b), which is internationally sold by the same manufacturer under the brand names uhu kontakt kleber and griffon contact. the yellowish brown colour of this glue does not affect the colour of the final peel. neoprene rubber contact adhesive is also known as polychloroprene glue, contact cement, or contact adhesive, and is elsewhere sold by manufacturers such as m, dap weldwood, pliobond, and k-flex-usa – check the suitability of these products in the field before purchas- ing large volumes. because some of these brands still contain toluene, it is also advisable to request (material) safety data sheets (known as (m)sds in the usa) to check for any re- quired personal protective equipment. the volume of glue (vg, l) required to make a peel, in- cluding excess edges and mounting the peel, is calculated as eqs. ( ) and ( ): vg = . × (bw + . )× (bl + . )+vm, ( ) vm = . ×bwbl, ( ) where bw (m) and bl (m) are the width and length of the wooden board and thus the final size of the peel, respectively, and vm (l) is the volume of glue needed to mount the peel to the wooden board. for a final peel size of × cm, l is sufficient. at a cost of – eur l− , the total costs of a typical profile amount to under eur . as many stores allow return of unopened cans of glue, we typically purchase more glue than we need and return the excess. . general preparation . . find a good location finding a good location can just be a matter of being outside a lot, knowing the surroundings, and scraping off the outer few centimetres of an exposed road cut to reveal the origi- nal soil underneath. in the old days (up to the s) when workload at universities was still low, frequent and lengthy soil mapping field courses allowed for many opportunities to find beautiful soils and capture them in peels. alternatively, with less time spent outside, good locations can also be found using digital maps that are often available online. whether outside or behind a computer, four main factors determine the suitability of a location for making a soil peel: ( ) soil texture, ( ) groundwater depth, ( ) a natural or man-made exposure, and ( ) accessibility (fig. a). first, regarding soil texture, lacquer peels are best made in unconsolidated sandy deposits (such as commonly found in delta areas) with low clay, silt, and organic content and ideally low rock fragment or gravel content. clay and silt have low permeability (rawls et al., ), and so does or- ganic matter when compacted (ohu et al., ), and thereby result in very shallow impregnation of the glue, causing po- tentially fragile layers. based on years of field experience in making soil peels we found that the textural classes “sand” and “loamy sand” (soil science division staff, ) are best suitable. this indicates that the clay+silt content should not exceed %, with a maximum of % clay. the minimum sand content should therefore be %. at the same time, the organic matter content should not exceed ∼ % (humic con- ditions, sensu de bakker and schelling, ). rock frag- ments and gravel are challenging to work with because they affect the smooth preparation of the soil face (sect. . ) and additionally may fall off the final peel (sect. . ), although results can still be quite successful. to find locations with suitable soil texture and organic matter content, the s-world model (stoorvogel et al., ) and the soilgrids tool (is- ric, a; batjes, ) are both valuable and free re- sources. this can be verified with local soil maps and/or as- sessment of texture (nrcs, ; thien, ) and organic matter content (schulze et al., ; wills et al., ) in the field. soil, , – , www.soil-journal.net/ / / / c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty table . materials required and their purpose. material purpose . g en er al pr ep ar at io n . f ie ld pr ep ar at io n . g lu ei ng . p ee le xt ra ct io n . m ou nt in g . f in is hi ng ruler, measuring tape to stake out the lacquer peel di- mensions × to determine the finished peel dimensions × spade, shovel to make a smooth soil face × to clean up excavated sand × soil knife (nisaku horihori weeding knife, tomita cutlery co. ltd., koseki tsubame-si niigata japan. alternative: large serrated knife with a big handle) to shape the ledge × to dig out the peel after the glue has dried × garden clipper/pruner × nail clippers ( ×) to cut small roots × × polychloroprene glue to secure the soil particles × garbage bag, pvc pipe sliced in half to construct a collection unit to capture excess glue × × sturdy garbage bags or bucket to transport empty glue con- tainers (potentially sticky), ex- cess glue × to transport cut off lacquer peel × × notched trowel to evenly spread glue on wooden board × stanley knife to cut off all parts of the lac- quer peel that extend beyond the wooden board × workers gloves protect hands during digging, etc. × × × latex gloves protect hands while glueing board × wooden board to support extraction and trans- port of lacquer peel × to mount lacquer peel on × blanket, cloth to prevent lacquer peel from breaking × hooks for mounting on wall × www.soil-journal.net/ / / / soil, , – , c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty figure . main steps of making a soil peel. soil, , – , www.soil-journal.net/ / / / c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty second, groundwater depth is important because results are best if soils are dry, since the glue used does not ad- here properly when soils are wet. groundwater level varia- tion can be part of hydrological monitoring setups, but can also be recorded on soil maps as the average highest and lowest groundwater levels (e.g. bis nederland, ). given that warm and dry weather in late spring or summer is of- ten most beneficial for making soil peels, the most relevant groundwater information there is the average lowest ground- water level (which occurs in summer). the global map of groundwater table depths created by fan et al. ( ), albeit coarse, can give a first indication of whether a region may be suitable for making soil peels. alternatively, high (sea- sonal/perched) groundwater depths can moreover be inferred from soil type (e.g. fluvisols, luvisols) and geomorphol- ogy (e.g. lower river terraces, floodplains, wetlands, glacial till landscapes prone to hardpan formation), the information of which can be found on soil maps and geomorphological maps. subsequent combination of soil texture, organic mat- ter, and groundwater information can then provide insight into where peels can be made (e.g. fig. ). combined with information about capillary rise (∼ . cm in gravel to > m in silt; singhal and gupta, ), locations of suitable dry- ness can be found, which is in soils and sediments above the capillary fringe. third, an exposure is essential when making lacquer peels of vertical cross sections of soil or sediment. this exposure can be created by digging a soil pit, which can be done by hand. approximately m is needed to have sufficient work space, with a . – . m depth of the pit to obtain a . – . m long peel. however, as digging a pit can be time-consuming, the most ideal places to make peels are natural drops in el- evation such as eroded river banks, or man-made cases such as road cuts, quarries, construction works (river restoration, cable installation), or archaeological digs. contact local au- thorities or companies to ask for temporary opportunities, or consult elevation maps for more permanent locations. ele- vation maps are often available online. detailed digital el- evation models (dems) may also be used; for example, the ahn (actueel hoogtebestand nederland) in the netherlands is a freely available elevation map with a resolution of . by . m (van heerd and van’t zand, ). international ex- amples include the eu-dem with a resolution of by m (eea, ). exposures such as quarries may additionally be found from aerial photography (e.g. google earth). . . arrange permission locate the landowner and ask their permission. as many non-soil scientists do not know what a lacquer peel is, a sim- ple explanation free of scientific jargon is to refer to it as a “soil painting” or “soil art”. be honest about the use of glue, but also explain that you will clean everything up. check whether the landowner would like to receive notice about the exact moment the fieldwork is planned – though as the process of making a soil peel is weather-dependent, this can often not be indicated much in advance, and acknowledge them in activities resulting from work on their land. making soil peels can be an opportunity to involve land owners as an outreach activity, by having them on site, or sharing infor- mation (photo/video) about the process. in the dry summer of , we created three soil peels on wageningen university farmland with the pit excavated by unifarm (farm services) – in return we made a fourth soil peel for unifarm outreach activities. . . get the timing right in some climates, planning ahead for making lacquer peels can be challenging as this activity is rather weather depen- dent. results are best when soils are dry, creating more in- tense colours and higher contrast of colours in the peel. in the netherlands, our experience with the “soil profile week- ends” taught that weeks of dry weather in late spring or summer are sufficient to achieve good results. we have never had issues with soils that were too dry, and with the materials we use there is no need to spray the soil with water as sug- gested by bouma ( ). while it is possible to make a peel when the soil is moist, the result is not as beautiful because of reduced appearance of for instance podzol fibres, or sim- ply because the glue will not adhere to the sand. note that while soil moisture contents may strongly vary in time, there may also be considerable differences within a soil profile. when sand may be already dry, horizons with more organic matter or clay can still be quite moist because of their strong effect on soil water retention (rawls et al., ; wösten et al., ). these within-profile differences may be exacer- bated by impermeable layers: we once encountered major is- sues when extracting a peel from a podzol that had a perched water table due to an impermeable bh horizon. while appli- cation of the glue (sect. . ) was successful, the extracted peel showed that the glue had not adhered to the saturated e horizon above the bh, while the c horizon below the im- permeable layer was dry and adhered just fine. this peel was later restored in the lab (sect. . ) using dried sand collected from the e horizon. dry weather is recommended both in the couple of weeks before making a peel as well as during the days in the field (sect. . – . ), when air temperature is also important. fol- low the manufacturer’s recommendations regarding the tem- perature at which the glue can be used (e.g. – ◦c, bison international, a). particularly the first hours after im- pregnation are critical because any rain occurring soon after impregnation (within – h) may create bubbles in the glue, resulting in poor impregnation and therefore “bald” spots with reduced sand cover upon extraction. high relative hu- midity can potentially have similar effects (e.g. > %, bi- son international, a), although we have never had such issues in the field. www.soil-journal.net/ / / / soil, , – , c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty figure . overview of locations suitable for making soil peels in the world (sand content > %, clay content < %, organic matter < %, and temporal mean groundwater depth < . m). this global map was made using soil information obtained from isric (batjes, ; isric, a) and groundwater depth information provided by fan et al. ( ). . field preparation: prepare soil face and cut all roots . . prepare soil face use a spade to make a straight soil face at a ◦ (loamy sand) to ◦ (sand) angle (fig. b). the dimensions of the soil face to be impregnated should be somewhat larger than the in- tended size of the lacquer peel. make the soil face cm wider than the final peel on either side (fig. b), because it is never fully predictable how the glue will flow and thus what the final surface is that will be covered. also, extend it – cm below the bottom end of the intended peel to allow unimpeded flow. an additional benefit of making the soil face larger than the final size of the peel is that it al- lows selection of the best or most beautiful part of the profile for mounting. after all, the final appearance of the front of the lacquer peel remains hidden until after excavation, as the lacquer peel is a mirror image of the soil face. it is therefore always a surprise what the final peel will look like, which is why having additional space to choose the most beauti- ful part for installation on the board is useful. the prepared soil face should be as smooth and straight as possible – any bumps and hollows can hamper smooth distribution of the glue in the next step. perfection is not possible though, espe- cially when sediments are brittle or gravelly. it would not be the first time that removing “one last thing” can cause col- lapse of part of the soil face and thereby necessitate much larger restoration work before the glue can be applied. . . trim roots and remove rock fragments cut away all roots protruding from the soil face using garden or nail clippers (for large and small roots, respectively) and remove any rocks or large rock fragments (fig. c). roots or rocks that stick out will retain glue and can thereby create glue-less pockets that will appear as holes in the finished lac- quer peel. cut the roots as close to the soil face as possible while avoiding any dislocation of sand grains. this can be a rather tedious process as the number of roots can be surpris- ingly high. yet careful removal of roots and rock fragments will allow smoother impregnation of the soil face (step ), easier mounting of the peel on the wooden board (step ), and thus better final results. . . make ledge create a cm ledge above the soil face (fig. c), providing a place to pour the glue and preventing any soil material from above from falling onto the profile. if the top of the soil face is the same as the mineral soil surface, this ledge can be cre- ated by removing any litter and vegetation. if the top of the soil face starts mid-way a slope, this ledge can be made by simply cutting cm into the soil. . . install gutter position a gutter underneath the soil face that can collect any excess glue (fig. c). a piece of pvc pipe (diameter – cm) sliced in two and then capped on both ends can func- tion as a good gutter, although a plastic bag may also do if soil, , – , www.soil-journal.net/ / / / c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty positioned well. if the firmness of the soil profile allows, cut a cm overhang below its bottom and locate the gutter un- derneath this overhang. the total time required for field preparation strongly varies with the degree of care taken when preparing the soil face – a general time estimate for this step is ∼ h for soils with a good rooting pattern. in sediments with no roots this step can be done in – min. . impregnation: securing the sand grains with glue . . apply the glue to allow for rapid application of the glue, open all the cans of glue and place them within reach of the soil face – or close to a helping hand who can give the cans to the per- son applying the glue. in contrast to the previously discussed older methods that required on-site mixing of glues or lac- quers with thinning chemicals, glues used here are ready- for-use and can thus be used straight out of the can. ap- plication of the glue on the soil face is easiest when using wide-mouth cans (∼ cm diameter); we recommend using an empty vegetable can for pouring if the glue container has a narrower opening. gently pour the glue by starting at the top ledge and moving the can across the width of the profile in a zig-zag pattern (fig. d). while the glue moves downwards, also move down the location where the glue is applied. most likely, a finger-like pattern will appear in the glue (fig. d, video s in the supplement), especially when the soil face is rather vertical. this preferential flow is caused by the fact that liquids have a strong tendency to follow existing zones of (even slightly) higher liquid content (liu et al., ), be- cause of the large differences in hydraulic conductivity and thus flow velocity in dry and wet materials. fill in the gaps between the preferential flow paths by pouring glue at their top and continue this process until the glue has reached the bottom of the soil face. when the bottom of the profile is reached, the impregnation stage is finished. we recommend application of only a single layer of glue: we qualitatively tested the effect of adding additional layers of glue, which did not improve the final product. in one case, application of a second layer of glue even resulted in movement of the initial layer, creating a glue-less patch and thus a hole in the final peel. . . clean up with the glue application done, the impregnation step of making the lacquer peel is finished. the neoprene rubber contact adhesive is so strong and yet flexible within the first days of application that it can easily hold the weight of a soil profile without tearing. as such, reinforcement of the peel with cheesecloth as directed by bouma ( ) is not re- quired. collect any excess glue that is still liquid from the top ledge and the bottom gutter. remove all trash and leave the site such that any visitors (people or animals) cannot harm themselves. cover the impregnated soil face with a large (fisherman’s) umbrella if there is a chance of light rain, and wait – h to let the glue dry (fig. e). the exact drying time will depend on meteorological conditions (air tempera- ture, relative humidity, and wind) and exposure of the profile. it may be that the profile is dry and ready for extraction af- ter less than – h. testing of potentially reduced drying times in different conditions is advisable in cases where time is tight and weather conditions are advantageous. . extracting the peel . . clear sides extraction of the peel from the soil face involves the repo- sitioning of a lot of loose sand from behind the peel to the sides. to facilitate this sand removal, make sure that the soil face on either side of the impregnated section is flush with the lacquer peel for a width of ∼ cm on either side. it is also advisable to remove sand around the bottom of the profile. . . cut out peel from above everything is now in place to start digging out the peel from above using the serrated edge of a (soil) knife. starting at the top ledge, use the (soil) knife like a saw to make a cut – cm behind the glued soil face across the entire length of the peel (fig. f, video s ). the knife cuts fine roots; use garden clippers to cut off larger roots ∼ – cm away from the glue. the further out from the glue you make these cuts, the longer the roots will be that stick out of the finished peel, which can always be trimmed in step (sect. . ). extraction of the soil peel is best done with two people, and can be done from the top (as outlined here) or from be- low (as outlined by bouma, ). to extract the peel from the top, one person cuts away the soil and moves loose sand away from behind the profile and works their way down the profile. once the top of the lacquer peel has been freed, a sec- ond person then presses a wooden board against the soil face that supports the top of the profile against the board (fig. f, video s ). this is to support the peel and prevent any tearing along fragile layers such as podzol fibres or thin loam bands. if the peel is heavy, for instance in the case of very structured soil, it can be partly folded over the top of the wooden board. covering the edge of the wooden board with a thick towel can then reduce the risk of tearing that can occur in fragile layers. digging out the lacquer peel can be easy and straightfor- ward if the peel is small and does not contain roots or con- cretions. very small profiles (e.g. by cm) can even be done by a single person. extracting a more typically sized peel (e.g. cm wide by cm long) is not necessarily dif- ficult, but it can be arduous if layers are densely rooted or structured. still, to min is usually sufficient to remove peels from a soil face. www.soil-journal.net/ / / / soil, , – , c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty . mounting the peel . . choose your mounting location the extracted soil peel can be mounted on a wooden board either directly in the field or after transporting the peel to a laboratory, shed, carport, or garage. mounting the peel in the field allows for safer transport, yet it does typically mean that the size of the wooden board and thus the final size of the lacquer peel is predetermined – unless there is a possibility of bringing power tools to the field to trim a board to size. using a fixed board size is not a problem when making soil peels for teaching or outreach collection, but when using peels for soil art it can be worthwhile to determine the final peel size after extraction. after all, since the peel is a mirror image of the soil face (as discussed in step ), its final appearance remains a surprise until it is extracted from its location. . . test positioning when ready to mount the peel, test its position on the wooden board to decide which features to keep. measuring how much the peel will extend beyond the sides of the wooden board helps exact positioning once the board is glued. if the peel is too heavy to lift, reduce its weight by removing large aggre- gates by hand and/or by very carefully removing any large clumps of soil with a soft brush. a brush may also be used to remove loose sand (always stroke sand away in the direction of any soil layering), but only if the glue is fully dry. . . glue the wooden board cover the wooden board with some of the remaining glue (fig. g), making sure to particularly cover its sides and cor- ners as these are the most vulnerable parts of the finished peel. use of a notched trowel facilitates an even spread of the glue, while corners and sides can be reached by hand us- ing household gloves. work swiftly as the glue dries quickly, particularly when the weather is warm (> ◦c) and windy. . . attach peel to board lift the lacquer peel up with two people and place it on the wooden board directly in the desired location: as the glue will create an instant grip, changing the alignment of the lacquer peel will be very challenging if not impossible. . . press peel in place carefully but firmly press the lacquer peel to the wooden board with your fingers. again pay particular attention to the sides and corners of the wooden board to secure these well. . . remove loose sand turn the peel on its side and release any loose sand still rest- ing on the peel by manually knocking the back of the wooden panel. repeat until no sand falls off anymore. keep some ex- cess material from each layer (soil, any rock fragments, large roots) to restore any damaged patches later if needed. . . trim peel to size now that the peel has been secured to the wooden panel, trim it using a sharp (stanley) knife (fig. g). with one side of the knife touching the side of the wood, cut off all parts of the soil peel that extend beyond the wooden board. retain strips to make mini-profiles or to test the effects of impregnation with a fixing agent (sect. . ). . . restore any damaged patches and trim roots (if desired) in some cases peels may have small holes or damaged patches if glue distribution was not uniform or where rock fragments or larger roots have fallen off. these patches can be easily restored by applying some glue and covering them with the appropriate material for that layer, such as soil par- ticles, a rock fragment, or a large root. this is also the mo- ment where roots can be trimmed if desired using shears or nail clippers. there is no predetermined root length: the final root length is very much part of the artistic freedom and the message that is communicated with the soil peel, if any. . finishing, installation, and maintenance . . ventilate the soil peel now requires some rest in a well-ventilated place to let the glue fully solidify – we ventilate our pro- files for a minimum of days. as glue fumes can be rather intense, a garage, shed, or covered dry outdoor location is best for this. make sure to place the lacquer peel in a hori- zontal position – placing it vertically shortly after mounting may result in vertical movement of the drying glue and thus distortion of the soil profile. . . finish many authors suggest impregnating the undisturbed front of lacquer peels (e.g. huisman, ; tno, ) to intensify the colours of the soil particles and secure any loose parti- cles. our team did that from to using a large can of the cheapest hairspray sold at the local pharmacist, apply- ing it week after the soil peels were mounted. the hairspray did bring out the colours more, but once surprisingly pro- duced such dark colours that any colour variation in the peel was obscured. it may be that the formula of the hairspray had changed, but the exact reason for this dramatic colour change was unknown. since then, we have not sprayed peels anymore and are very satisfied with the original colours. as such, there was no need to find an alternative impregnation material. in the case that colours are weak, spraying with soil, , – , www.soil-journal.net/ / / / c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty hairspray can be a way to intensify colours, but we strongly recommend testing of results along the entire length of the lacquer peel using the trimmed-off edges of the peel. in that case, turn the profile on its side to knock off any loose parti- cles before spraying and ventilate again for a few days before installation. . . install after a week of rest when the glue will be firm and odourless, the finished lacquer peel can be installed in its final location. hooks screwed into the top of the board allow it to be hung vertically on a wall in a classroom, office, living room, mu- seum, or wherever this piece of science art is desired. if de- sired, slats can be used to construct a wooden frame around the finished lacquer peel. . . maintenance we have heard reports of people annually impregnating their soil peel with spray to “maintain its colours”. we have never seen a need for this and do not perform any maintenance of the finished peels. after changing from lacquer to glue, preservation of our peels has improved such that even in- tensive use in hands-on teaching does not degrade the peels anymore. if required, dust can be carefully removed from between any roots using a vacuum cleaner set at its lowest speed. discussion and conclusion high participation in the maker-ed and diy movements (holtzman et al., ; atkinson, ) indicates renewed interest in making things at home, while the potential of visu- alization is being recognized in science communication and education (evagorou et al., ; venhuizen et al., ). at the same time, there is increased interest in the value of soils for life (keesstra et al., ; fao, ). the creation of soil and sediment peels combines all these aspects, and can be done by non-specialists. materials including glues are readily available at hardware stores, and even novices can create beautiful peels. here we discussed the benefits of using peels and the challenges posed by the old methods (e.g. voigt and gittins, ; van baren and bomer, ; bouma, ) used to create these peels. we described the main steps of making a soil peel: impregnation of a smooth soil face with glue in the field before extracting the peel and then mounting it on a wooden panel. because of a techno- logical advance in the impregnation material (going from lacquers to glue), the method reported here is safer, sim- pler, more successful, more durable, and more accessible be- cause ( ) the glue can be used without the use and mixing of toxic chemicals in the field, ( ) the firmness of the resulting peel is such that additional support materials (such as cheese- cloth) are not required, and ( ) consequently the soil peel will last for a long time, even when intensively used in hands- on teaching. while this method can be applied to a range of moisture contents and sand textures, further research on the best environmental conditions is required for those inter- ested in achieving perfection in terms of appearance. similar exploration is advised for alternative glues. such additional research would be valuable for some (e.g. soil museums), but based on our experience, we believe that those simply interested in capturing a beautiful snapshot of soils can do so with the more qualitative guidance described in this pa- per. we hope that this thoroughly tested successful and sim- ple method will inspire and enthuse researchers, educators, and the general public to make soil lacquer peels and thereby bring the value and beauty of soils to a wider audience. data availability. data used in this article can be found in sect. , table and video s . video supplement. video s can be downloaded free of charge from the tib-av portal (https://doi.org/ . / , stoof et al., ). supplement. instruction video showing how to make a soil peel in the field. the supplement related to this article is available online at: https://doi.org/ . /soil- - - -supplement. author contributions. crs conceptualized the main ideas, with input from jhjc and gp. gp developed the methodology, with in- put from crs and jhjc. visualizations were made by lagmvdw, who coordinated the video with help from jhjc and crs. crs wrote the manuscript with contributions from all co-authors. competing interests. the authors declare that they have no con- flict of interest. disclaimer. any use of trade, firm, or product names is for de- scriptive purposes only and does not imply endorsement by wa- geningen university and research. acknowledgements. cathelijne r. stoof, jasper h. j. candel, and laszlo a. g. m. van der wal dedicate this paper to educator gert peek (now retired), whose enthusiasm for soil science teach- ing and outreach has inspired thousands of students and staff. we thank stephan mantel (isric-world soil information) for sharing information about the numerous institutes around the world that is- ric has supported to make soil monolith collections, which greatly contributed to creating the global overview of locations with pre- served soil profiles listed in table . for any additions to this ta- ble, please contact isric, who will be keeping updates. we would additionally like to thank two anonymous reviewers for their con- www.soil-journal.net/ / / / soil, , – , https://doi.org/ . / https://doi.org/ . /soil- - - -supplement c. r. stoof et al.: soil lacquer peel do-it-yourself: simply capturing beauty structive comments, and a large number of others for their help in sourcing the data in table : albert bos, alberto orgiazzi, alejan- dro becerra, alessandro samuel rosa, bernd andeweg, bram te brake, christine morgan, coen ritsema, colby moorberg, darya van tienhoven, erin bush, franciska de vries, hayley craig, ich- sani wheeler, jacqueline aitkenhead-peterson, jacqueline hannam, jakob wallinga, jantiene baartman, jerry maroulis, jetse stoor- vogel, karen vancampenhout, keiko mori, kim cohen, kirsten van der ploeg, liam heffernan, marcos angelini, maurica fitzgib- bons, meredith steele, michael strickland, mickey ransom, mir- zokhid mirshadiev, nssc-gru, nynke schulp, piotr pacanowski, rachel creamer, richard bardgett, richard kraaijvanger, royal ei- jkelkamp, steffen schweizer, sytze van heteren, wieske wentink, wouter thijs, wouter van gorp, and zhanguo bai. we thank niels kijm for assistance with making the lacquer peel for the video in- structions, bob czaja and ann youberg for discussion of the types of glue that are internationally available, and bison international for information on the characteristics of bisonkit. cathelijne r. stoof has received funding from the european union’s horizon re- search and innovation programme under marie skłodowska-curie grant agreement no. . review statement. this paper was edited by john quinton and reviewed by two anonymous referees. references allaire, s. a. and bochove, e. v.: collecting large soil monoliths, can. j. soil sci., , – , . american museum of natural history: soils and soil con- servation, available at: https://www.amnh.org/exhibitions/ 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https://doi.org/ . / https://doi.org/ . /sssaj . http://ygk.uz/uz/node/ abstract introduction taking the soil peel: six main steps collect the required materials materials needed characteristics of the glue general preparation find a good location arrange permission get the timing right field preparation: prepare soil face and cut all roots prepare soil face trim roots and remove rock fragments make ledge install gutter impregnation: securing the sand grains with glue apply the glue clean up extracting the peel clear sides cut out peel from above mounting the peel choose your mounting location test positioning glue the wooden board attach peel to board press peel in place remove loose sand trim peel to size restore any damaged patches and trim roots (if desired) finishing, installation, and maintenance ventilate finish install maintenance discussion and conclusion data availability video supplement supplement author contributions competing interests disclaimer acknowledgements review statement references beastly beauty products: exposure to inorganic mercury in skin-lightening creams | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . /ehp. -a b corpus id: beastly beauty products: exposure to inorganic mercury in skin-lightening creams @article{washam beastlybp, title={beastly beauty products: exposure to inorganic mercury in skin-lightening creams}, author={c. washam}, journal={environmental health perspectives}, year={ }, volume={ }, pages={a - a } } c. washam published biology, medicine environmental health perspectives the most common exposure to mercury is from organic methylmercury found in fish. people with no workplace exposure to mercury typically have low levels of exposure to inorganic or elemental mercury, although nonoccupational exposure can occur from dental amalgams, some herbal medicine products, and cosmetics that contain mercury. when a new york city (nyc) biomonitoring study revealed that thousands of women in that city may have been exposed to dangerous levels of inorganic mercury from… expand view on pubmed doi.org save to library create alert cite launch research feed share this paper citationshighly influential citations background citations view all topics from this paper dietary mercury methylmercury compounds adverse reaction to drug dairy cream neurotoxicity syndromes united states food and drug administration part per million (ppm) dental amalgam amalgam (silver) dental filling material laboratory specimen renal tissue mental disorders chemical hazard release citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by most influenced papers sort by citation count sort by recency novel lipid-soluble thiol-redox antioxidant and heavy metal chelator, n,n′-bis( -mercaptoethyl)isophthalamide (nbmi) and phospholipase d-specific inhibitor, -fluoro- -indolyl des-chlorohalopemide (fipi) attenuate mercury-induced lipid signaling leading to protection against cytotoxicity in aortic e jordan d. secor, sainath r. kotha, + authors n. parinandi chemistry, medicine international journal of toxicology highly influenced pdf view excerpts, cites background save alert research feed skin bleaching: a neglected form of injury and threat to global skin jalika c. street, karie a gaska, k. lewis, m. wilson medicine highly influenced view excerpts, cites background save alert research feed extent of use of skin bleaching agents and associated factors among female college students in ilala district, dar es salaam o.i.n. machangu medicine view excerpts, cites background save alert research feed current application of phytocompound-based nanocosmeceuticals for beauty and skin therapy p. ganesan, d. choi materials science, medicine international journal of nanomedicine pdf save alert research feed facial abuse of topical steroids and fairness creams: a clinical study of patients samina naz chohan, majid suhail, + authors taqdees suhail medicine pdf view excerpt, cites background save alert research feed potential health consequences of applying mercury-containing skin-lightening creams during pregnancy and lactation periods. i. al-saleh medicine international journal of hygiene and environmental health view excerpt, cites background save alert research feed heavy metals in female adolescents i. yunusa, m. ibrahim, + authors l. ezeanyika chemistry view excerpt, cites background save alert research feed direct analysis of mercury in cosmetics using screen-printed silver electrodes and flow injection analysis h. yang, pei-yen chen, p. ho, y. shih chemistry save alert research feed toxic metals and autophagy. sarmishtha chatterjee, s. sarkar, s. bhattacharya biology, medicine chemical research in toxicology save alert research feed novel lipid-soluble thiol-redox antioxidant and heavy metal chelator, n,n -bis( -mercaptoethyl)isophthalamide jordan d. secor, sainath r. kotha, + authors n. parinandi chemistry save alert research feed related papers abstract topics citations related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue big is beautiful: science (and art) in wood microscopy nigel chaffey swedish university of agricultural sciences, ume&, sweden abstract notwithstanding the importance of trees, considerable technical prob- lems have severely restricted study of the fine structure of the vascular cambium and the wood and bark that it produces. and despite the advent of immunocytochemical techniques, it is only in the last few years that the roie of the cytoskeleton in the process of secondary vascular differentiation has been studied. yet, for those who persist with this intractable material, the experience can be rewarding. this article discusses the difficulties involved in microscopy of this material, and offers some solutions. introduction if you were told of a plant where a single cell type could give rise to different cell types; or in which ceils up to several millimeters long could divide perfectly for many thousands of years; or whose cells contained some of the most interesting microtubule arrays yet seen in the plant world, you might not believe it. or, if you believed it, you would assume that it was bound to have been intensively studied already. well, such a plant does exist, the tree. yet its vascular cambium, which performs these wonderful feats, has largely been left untouched from a ceil biological point of view. this is both surprising and disappointing, because trees are as important today as they have been for many hundreds of years, e.g., in providing wood for building or wood-pulp for paper manufacture (and notwithstanding their role in removing the excesses of c liberated by the burning of fossil fuel reserves, and hence in stabilising climatic changes..,), further, given the current high level of interest in 'green issues', trees are being looked at anew as an environmentally- friendly renewable source of energy, or, to put all this another way, trees are very important. their importance derives largely from the activity of the vascular cambium, a sheath of tissue which encircles the stem or root, which by repeated cell division not only maintains itself but also gives rise to sec- ondary xylem cells ('wood') to its inside and secondary phloem ('bark') to the outside. phloem is the major fong-distance transport pathway for sugar, e.g., from leaves to roots and other non-photosynthetic regions of the plant. xylem contains vessels, the main conduits for long-distance water transport from roots to leaves. the formation of the secondary vascular tissues - secondary xylem and secondary phloem - is termed secondary growth (or secondary thickening) and is largely responsible for the growth in diameter of trees. the developmental continuum of secondary phloem, cambium, and secondary xylem is termed the secondary vascular system (svs). in view of the importance of trees and the abundance of modern techniques for study of cell biology, why has the svs received so little attention from developmental biologists in recent years? there are two main reasons: one, the svs, particularly the cambium, is perceived as being difficult to study, and two, secondary growth is rarely taught to the same degree as other aspects of plant growth and development, so that it never receives the publicity it deserves. i have an interest in the cytoskeleton in the cambium, and its role in cell differentiation within the svs of hardwood (angiosperm) trees (chaffey ef at,, , a,b,c). in order to study this cell component, using indirect immunofluorescence microscopy (hf), i have had to come to terms with the idiosyncrasies of the svs in developing techniques that would allow me to unlock some of its secrets. this article has been written to show that the svs of trees can be studied, and to encourage others to study this fascinat- ing developmental system. the problems... of relevance to any technique of study: ) cells of the cambium are: a, thin-walled, b, highly vacuolate, and, c, sandwiched between much thicker-walled xylem and phloem cells ) the svs is often quite deeply embedded within the stem (or root). } cambium contains two distinct cell types: axially-elongated fusiform cells, and cuboid ray cells, which eventually become elongated in the radial plane of the stem (or root). ) the svs contains many types of cells which are at different physiologi- cal states/stages of differentiation, ) when the cambium is active in cell production, it tears easily during sampling. ) sections of the svs adhere with difficulty to glass microscope slides. ) the svs is -dimensional. ...of relevance particularly to immunocytochemical studies: ) the svs contains many compounds which fluoresce naturally ) cell preservation is compromised by the low concentrations of fixative that can be used ) there is difficulty in finding a suitable embedding medium. overcoming the 'problems'... ) without a doubt, these features of the cambium make it difficult to work with, but quite stunning images can be obtained (see farrar and evert ), although, it is essential to try a range of fixation procedures to find what suits your material, fairly standard mixtures of formaldehyde and glutaraldehyde in the 'usual' range of buffers all seem suitable, and, on the 'plus' side, the very robustness of wood cells means that processing them for scanning electron microscopy can be as simple as air-drying and metal coating (e.g., chaffey ef a/., ). ) the location of the svs is a major hindrance to its ready removal, a problem which is exacerbated for those who work on roots! however, as long as one works reasonably quickly (but safely!) - with hack saw and razor blade (for saplings) (chaffey ef at., c), or with hammer, chisel and razor biade (for more mature specimens) (barnett, } - samples can be removed, ) the differences between the two cell types in the cambium - and indeed in the svs generally - potentially demand different processing strategies, if considered separately. however, the distribution of cell types is often unpre- dictable, so any sample contains a mixture of both. consequently, the processing requirements of the long fusiform cells take precedence, and the key to success- ful preparation is to think big! during my apprenticeship in transmission electron microscopy (tem), i was taught to have cubes of tissue with sides no greater than mm, that strategy is entirely inappropriate to the svs where individual cells can be up to mm long. figure illustrates a recommended sampling technique for saplings. the essential point is to excise and fix targe slivers of material but with a thickness of approximately - mm. that way the smallest dimension is in the range of 'traditional tem', this permits ready access of fixatives to cells, etc, whilst the larger dimensions ensure that entire cells are being fixed. after initial fixation, terminal portions of the slivers are removed (to eliminate damaged regions), before trimming to final block size, a more manage- able mm x mm x - mm. even if whole cells are not present in these smaller blocks, the portions of cells that are present should be fixed and their structure faithfully preserved. ) the sheer variety of cell types is one of the exciting features of the svs, but another confounding factor to its successful microscopical study, cells are at different stages of differentiation and it is (practically) impossible to find a procedure which will fix them all equally well. the fixation regime i use seems a reasonably good compromise as judged by the overall quality of the micrographs (see chaffey er at., b). although it is worthwhile comparing results from a range of fixations, ultimately, you have to devise a protocol whose images you can believe in. ) tearing of the 'cambium' is a long-established marker of the spring reactivation of this tissue in temperate trees - when cambiai cell walls become thin again after the period of winter dormancy, and cell division is resumed-and is known as 'bark slippage'. it occurs both in stems and roots and is a major problem in sampling the svs. although it is widely believed that the tearing takes place in the cambium, this is rarely the case. the rupture usually occurs within the zone of developing vascular derivatives where the cells have relatively thin walls and are undergoing radial expansion, depending on whether phloem or xylem is made first upon resumption of cambiai cell division, the cambium will either remain attached to the xylem, or be removed with the bark, respectively. bark slippage occurs throughout the period when the cambium is active, but is not - - d o w n lo ad ed fro m h ttp s://w w w .cam b rid g e.o rg /co re . c arn eg ie m ello n u n iversity , o n a p r at : : , su b ject to th e c am b rid g e c o re term s o f u se, availab le at h ttp s://w w w .cam b rid g e.o rg /co re/term s . h ttp s://d o i.o rg / . /s http://crossmark.crossref.org/dialog?doi= . /s &domain=pdf https://www.cambridge.org/core https://www.cambridge.org/core/terms https://doi.org/ . /s a feature of the dormant period (late autumn to spring), i only stress the need to be as careful as possible in excising and processing the slivers. ) it is well-known that sections of wood are difficult to stick to slides (e.g., o'brien and mcculiy, ). with sections in steedman's wax and butyl- methyimethacrylate (bmm), i have had most success using mayer's egg albumen (chaffey ef at., , c), although i have not tried gelatin (suggested by o'brien and mccully, ), neither poly-l-lysine coating nor silanization of slides worked for me. ) of course, everything is -dimensional, but it is stressed that the svs is an intimate association of axial cells derived from fusiform cambial cells (long cell axes parallel to long axis of organ) such as vessel elements, fibres, and sieve elements, and radial elements derived from ray cambial cells (long cell axes at right angles to long axis of organ), and the xylem and phloem ray cells. therefore, to appreciate fully the inter-relations between the component cells of the svs, it is essential to study the system in all three of the main planes, necessitating the cutting of transverse (cross) sections (ts), and radial (rls) and tangential longitudinal sections (tls). consequently, considerable care is required in correct orientation of blocks when embedding. the major drawback of ls's relative to ts's is that the slightest 'deficiencies' in fixation always seem much more obvious. however with care - and luck! - excellent ls's can be obtained (see farrar and evert, ). and ls's are essential for interpretation of the cytoskeletal arrangements in the svs, since a ts only reveals the thin parietal layer of cytoplasm in each cell. a useful tip for achieving good rls's is to ensure that slivers are excised from the diameter of the sampled organ. although this usually means that only two slivers can be removed at any given position, this practice will save many hours of disappointment in trying to interpret 'obiique rls's'. however, it seems that nature not only abhors a vacuum, she's not too keen on straight lines either, and it will soon become apparent that cells rarely lie perfectly horizontally or vertically in the organ. thus, cells will appear to weave in and out of the plane of section, because they do! another source of confusing images is that individual cells of the svs are usually different lengths and frequently arranged in a non-storied arrangement. non-storied refers to the cambium wherein the component cells overlap laterally so that they terminate at different levels in the transverse plane, since there appears to be more cyto- plasm at the ends of the cells (same thickness of cytoplasm, but smaller cell diameter), they can easily be mistaken for a different cell type, by reference to their more-vacuolate neighbours. ) chlorophyll, lignin and tannin are famously fluorescent materials and can be major irritants in iif of the svs. depending on the fluorochromes you are using, native fluorescence may be more or less of a problem: choose with this in mind, chlorophyll fluorescence is not a problem in roots, a much neglected area of svs study (chaffey ef at,, b). however, most people concentrate on the aerial portions where chlorophyll can be a major problem, although the wave- length of maximum emission is unlikely to interfere with fitc (fluorescein isothio- cyanate), the major fluorochrome used in iif, most of the offending pigment is removed by the ethanol during dehydration of the tissues, but note some iif processing procedures do not employ dehydration (e.g., funada ef a),, } both tannins and lignin are particular problems, the former tending to be sequestered in vacuoles, e.g., of phloem ray cells, the latter is an integral component of ceil walls of most xylem cell types, and phloem fibres, of course, this is one of the occasions where -d fluorescence microscopy comes into its own (e.g., scanalytics inc., ). however, for those of us who must persist with epifluorescence, my approach has been to quench what autofluorescence i can, with toluidine blue (chaffey ef a/., c), and to tolerate what i can't. indeed, the red fluorescence of lignin under the fitc filter combination is a pleasant contrast to the green/yellow fluorescence of fitc, and useful in indicating where lignifica- tion of xylem elements is beginning (e.g., chaffey ef at., a), use of cell wall polysaccharide-digesting enzymes (e.g., chaffey ef at., ) may contribute to partial removal of wall-located fluorescent material (and, possibly, improve access of antibodies to antigenic sites). other attempts to boost the 'signal: noise ratio' include the use of detergent (e.g., chaffey ef at., ; funada ef at., ) to puncture the plasmalemma to facilitate better penetration of antibodies - which is especially important in thick sections - up to [jm thick in conifers (funada ef s/.r ) and blocking of non-specific antibody binding (e.g., chaffey ef a/., c). one way to avoid the problem of autofiuorescence altogether, and that of fluorescence-fading, is to use immunogold localisation and silver-enhancement (e.g.,. sharon and spiegel, ), although to my mind it does not produce an image which is as aesthetically pleasing as that obtained by iif. allied to the problem of removing unwanted fluorescence is that of retaining the immunofluorescence, both lab-made p-phenylenediamine in glycerol (chaffey ef a/., ), and the commercially-available anti-fade mountant, vec- tashield™ (chaffey ef at., c), have been successful, with vectashield, useful fitc fluorescence can still be seen after slides have been refrigerated for several months. ) there is usually a compromise between 'good preservation' of structure and retention of antigenicity, and everyone has to find their own. certainly for tem, the problem is likely to be more acute than at the light microscope level, but faithful preservation of structure is required at all levels of investigation. there seem to be two aspects to the debate: one, how much 'conventional' preservation of structure can we 'get away with' before we have no immunostaining, and, two, how can we evaluate the effect of specific fixations, or pre-fixations, used to 'enhance' particular cell features? for conventional preservation in tem, it is usually necessary to include some glutaraldehyde in the fixation step(s) to retain any ultra structure (other than in walls and nuclei). for iif, formaldehyde alone may be sufficient (chaffey ef at., c), although addition of some glutaraldehyde wili usually improve the overall b / diagrammatic representation of sampling procedure, illustrated using the taproot of aesculus hippocastanum l. a - taproot from which samples are taken; b - excised cylinder of taproot material; c - sliver removed from cylinder and ready for primary fixation (for tem) or prefixation (for immunofiuorescence microscopy); d - fixed sliver marked-out for trimming to final size; e - final trimmed block ready for post-fixation (for tem), or overnight buffer-storage (for immunofluorescence microscopy). abbreviations: cz - cambial zone; p - phloem; x - secondary xylem; dashed line indicates location of cz, continued on next page - - d o w n lo ad ed fro m h ttp s://w w w .cam b rid g e.o rg /co re . c arn eg ie m ello n u n iversity , o n a p r at : : , su b ject to th e c am b rid g e c o re term s o f u se, availab le at h ttp s://w w w .cam b rid g e.o rg /co re/term s . h ttp s://d o i.o rg / . /s https://www.cambridge.org/core https://www.cambridge.org/core/terms https://doi.org/ . /s big is beautiful: science (and art) in wood microscopy continued from pre vious page quality of fixation (up to . % can be used in conifers (funada ef a/., ). and in hybrid aspen by my recent experience), however, one point that is often overlooked is that the antibody may have been raised against denatured antigen, so often a relatively high level of glutaraldehyde cross-linking of protein can be tolerated by the antibody, do not be afraid to experiment! note, however, that glutaraldehyde can introduce additional fluorescence which may be more of a problem than that of accepting slightly inferior tissue preservation. of course, that is not a feature of silver-enhancement or tem, and methods do exist for removing this fluorescence, e.g., by use of nabh or schiffs reagent (carnegie ef a!., ), if you are concerned by the use of 'pre-fixations' such as mbs ( - maleimidobenzoic acid w-hydroxysuccinimide ester for microfilaments - chaffey ef a/., c), or the inclusion of dmso (dimethyl sulphoxide for microtubules - chaffey ef al,, ; funada ef al., ) or 'microtubule-stabilizing buffer (chaffey ef al,, ), one way to check the 'reality' of the preservation is to compare the image with and without the agent (chaffey ef a/,r c). addition- ally, i would recommend a correlative approach of tem and iif (chaffey ef al., ): if two quite different preparative procedures give similar results, accept that 'consensus' view as being a reasonable approximation to reality. ) the embedding medium must be appropriate both to the technique of study, and the information that is sought. if one is only interested in gross anatomy/histology, then wax or butyl-methylmethacrylate (bmm) is ideal (as is tem material embedded in epoxy resin, except that the range of stains that can be used is more limited), for ultrastructural study, spurr's resin is ideal (chaffey ef a/,, b; farrar and evert, ). however, for immunogoid cytochemistry, an acrylic resin such as lr white (chaffey ef al., a,b) is to be preferred to epoxy resin at the tem level (although antibody penetration/antigen accessibility may be improved in the latter by various etching methods - e,g,,, crowley, ), light element peaks revealed! oil film on edx windows removed: c luutllluuuuulii, hllmlllll na i l l llllllllllllll,,! oily window clean window oil build-up on edx detector windows can rain sensitivity for light element x-rays in sems. to stop oil condensation and keep the system clean, smart sem users rely on the xei scientific sem-cleaf ' system. result: consistent light element x-ray results and contamination- free pictures. the nitrogen purge of the inexpensive sem-cleaw system actively cleans your election microscope while you're away. sem-clean" stops the oil s c i e n t i f i c wessex way, redwood city, ca - - - • fax - - http: //www .msa .micros copy. com/sm/xei/xe ihomepage.html for iif of cytoskeletal proteins in very young tree material it is possible to use a low melting point wax, such as steedman's wax (mp ° c) (chaffey era/., ). however, even with small amounts of secondary thickening it is necessary to use a harder medium, such as bmm, to prevent damage to the svs during cutting (chaffey era/., c), although iif study of polysaccharicte epitopes using jim antibodies is possible in lr white (chaffey ef al, b), bmm gives much cleaner preparations, which i attribute to the removal of this resin prior to immunostaining. final words if this article has helped to encourage others to accept the challenge of investigating the tree svs, i will be more than happy to have played my part in helping to ensure that this fascinating area of plant cell biology does not remain neglected! the svs is a 'challenging' system to work with. that is why it is so interesting and worthwhile, but by no means impossible. think big, persist, good luck - and don't forget your controls for iif (chaffey ef at., )! • references: barnett, j.r., , reactivation of the cambium in aesculus hippocas- tanuml; a transmission electron microscope study. ann, bot. ; - , carnegie. j.a., m.e. mccully, h a robertson, . embedment in glycol methacrylate at low temperature allows immunofluorescent localization of a iabile tissue protein. j. hist. cyto. ; - . chaffey, m.j, p.w. barlow, j.r. barnett, , microtubularcytoskeleton of vascular cambium and its derivatives in roots of aesculus bippocastanum l (hippocastanaceae), in: la, donaldson, b.g. butterfield, p.a. singh, lj, whitehouse, eds. recent advances in wood anatomy, new zealand forest research institute, rotorua, pp. - , chaffey, n.j., j.r. barnett, p.w. barlow, a. cortical microtubule in- volvement in bordered pit formation in secondary xylem vessel elements of aescufus hippocastanum l (hippocastanaceae): a correlative study using electron microscopy and indirect immunofluorescence microscopy. protoplasma ; - . chaffey, nj,, j.r, bamett, p.w. barlow, b. endomembranes, cy- toskeleton, and cell walls: aspects of the ultrastructure of the vascular cambium of taproots of aesculus hippocastanum l, (hippocastanaceae). int. j. plant sci, ; - . chaffey, n.j., j.r. barnett, p,w. barlow, c, visualization of the cy- toskeleton within the secondary vascular system of hardwood species. j, mi- crosc, ; - . crowley. h.h., , pretreating epoxy thin sections with sodium periodate prior to immunostaining, micro, today - ; - . farrar, j.j., r.f. evert, . seasonal changes in the ultrastructure of the vascular cambium of robinia pseudoacacia. trees ; - , funada, r., h, abe, o, furusawa, h. imaizumi, k fukuzawa, j. ohtani, , the orientation and localization of cortical microtubules in differentiating conifer tracheids during cell expansion. plant cell physiol. ; - . o'brien, t.p., m. e. mccully, , the study of plant structure: principles and selected methods. termacarphi, melbourne. scanalytics, inc., . high resolution -d fluorescence microscopy: a comparison of confocal laser scanning microscopy and a wide-field deconvolution technique. micro, today - ; - , sharon, e., y. spiegel, . gold-conjugated reagents for the labelling of carbohydrate-recognition domains and giycoconjugates on nematode surfaces. j. nematol. ; - . we would like to thank the royal microscopical society for permission to reproduce figure . this figure was originally published as figure in visualiza- tion of the cytoskeleton within the secondary vascular system of hardwood species by chaffey, nj, barnett jr, barlow pw in j, microsc. , pp. - ( ), circle reader inquiry # - - d o w n lo ad ed fro m h ttp s://w w w .cam b rid g e.o rg /co re . c arn eg ie m ello n u n iversity , o n a p r at : : , su b ject to th e c am b rid g e c o re term s o f u se, availab le at h ttp s://w w w .cam b rid g e.o rg /co re/term s . h ttp s://d o i.o rg / . /s https://www.cambridge.org/core https://www.cambridge.org/core/terms https://doi.org/ . /s twa-lens focusing column what does stand for? components our compact, uhv, field emission columns are used by researchers worldwide. innovative electrostatic optics and dedicated electronics allow you to integrate a high current density electron or ion column into most vacuum systems. fei also supplies researchers with other specialized products. labg and cebe cathodes fei's mini vogel mount, the first universally compatible long-life, high stability labe cathode, provides excellent performance and the best cost-per-use value for installation into your em systems. new components facilities dedicated fei components group facilities enabling new technology development through key investments in r&d and manufacturing. schottky field emission cathodes fei supplies schottky field emitters to em manufacturers worldwide. schottky emission's high current intensity has established it as the preferred electron source for high resolution sem,tem, auger, esca, edx, and lithography. components fei company nw evergreen parkway hilisboro, oregon - ( ) - fax ( ) - e-mail components@feico.com> subject of e-mail: "mtfei" now, when you think of fei components, you'll know we are the specialists in fieuektron and fa technology. circle reader inquiry # d o w n lo ad ed fro m h ttp s://w w w .cam b rid g e.o rg /co re . c arn eg ie m ello n u n iversity , o n a p r at : : , su b ject to th e c am b rid g e c o re term s o f u se, availab le at h ttp s://w w w .cam b rid g e.o rg /co re/term s . h ttp s://d o i.o rg / . /s https://www.cambridge.org/core https://www.cambridge.org/core/terms https://doi.org/ . /s () ar x iv : . v [ he p- ex ] m ay desy– – may measurement of beauty and charm production in deep inelastic scattering at hera and measurement of the beauty-quark mass zeus collaboration abstract the production of beauty and charm quarks in ep interactions has been studied with the zeus detector at hera for exchanged four-momentum squared < q < gev using an integrated luminosity of pb− . the beauty and charm content in events with at least one jet have been extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. differential cross sections as a function of q , bjorken x, jet transverse energy and pseudorapidity were measured and compared with next-to-leading-order qcd calculations. the beauty and charm contributions to the proton structure functions were extracted from the double-differential cross section as a function of x and q . the running beauty-quark mass, mb at the scale mb, was determined from a qcd fit at next-to-leading order to hera data for the first time and found to be mb(mb) = . ± . (fit)+ . − . (mod.) + . − . (param.) + . − . (theo.) gev. http://arxiv.org/abs/ . v the zeus collaboration h. abramowicz ,u, i. abt , l. adamczyk , m. adamus , r. aggarwal ,a, s. antonelli , o. arslan , v. aushev , ,o, y. aushev ,o,p, o. bachynska , a.n. barakbaev , n. bartosik , o. behnke , j. behr , u. behrens , a. bertolin , s. bhadra , i. bloch , v. bokhonov ,o, e.g. boos , k. borras , i. brock , r. brugnera , a. bruni , b. brzozowska , p.j. bussey , a. caldwell , m. capua , c.d. catterall , j. chwastowski ,d, j. ciborowski ,x, r. ciesielski ,f , a.m. cooper-sarkar , m. corradi , f. corriveau , g. d’agostini , r.k. dementiev , r.c.e. devenish , g. dolinska , v. drugakov , s. dusini , j. ferrando , j. figiel , b. foster ,l, g. gach , a. garfagnini , a. geiser , a. gizhko , l.k. gladilin , o. gogota , yu.a. golubkov , j. grebenyuk , i. gregor , g. grzelak , o. gueta , m. guzik , w. hain , g. hartner , d. hochman , r. hori , z.a. ibrahim , y. iga , m. ishitsuka , a. iudin ,p, f. januschek , i. kadenko , s. kananov , t. kanno , u. karshon , m. kaur , p. kaur ,a, l.a. khein , d. kisielewska , r. klanner , u. klein ,g, n. kondrashova ,q, o. kononenko , ie. korol , i.a. korzhavina , a. kotański , u. kötz , n. kovalchuk ,r, h. kowalski , o. kuprash , m. kuze , b.b. levchenko , a. levy , v. libov , s. limentani , m. lisovyi , e. lobodzinska , w. lohmann , b. löhr , e. lohrmann , a. longhin ,t, d. lontkovskyi , o.yu. lukina , j. maeda ,v, i. makarenko , j. malka , j.f. martin , s. mergelmeyer , f. mohamad idris ,c, k. mujkic ,h, v. myronenko ,i, k. nagano , a. nigro , t. nobe , d. notz , r.j. nowak , k. olkiewicz , yu. onishchuk , e. paul , w. perlański ,y, h. perrey , n.s. pokrovskiy , a.s. proskuryakov ,ab, m. przybycień , a. raval , p. roloff ,j, i. rubinsky , m. ruspa , v. samojlov , d.h. saxon , m. schioppa , w.b. schmidke ,s, u. schneekloth , t. schörner-sadenius , j. schwartz , l.m. shcheglova , r. shehzadi ,aa, r. shevchenko ,p, o. shkola ,r, i. singh ,b, i.o. skillicorn , w. słomiński ,e, v. sola , a. solano , a. spiridonov ,k, l. stanco , n. stefaniuk , a. stern , t.p. stewart , p. stopa , j. sztuk-dambietz , d. szuba , j. szuba , e. tassi , t. temiraliev , k. tokushuku ,m, j. tomaszewska ,z, a. trofymov ,r, v. trusov , t. tsurugai , m. turcato , o. turkot ,i, t. tymieniecka , a. verbytskyi , o. viazlo , r. walczak , w.a.t. wan abdullah , k. wichmann ,i, m. wing ,w, g. wolf , s. yamada , y. yamazaki ,n, n. zakharchuk ,r, a.f. Żarnecki , l. zawiejski , o. zenaiev , b.o. zhautykov , n. zhmak ,o, d.s. zotkin i infn bologna, bologna, italy a university and infn bologna, bologna, italy a physikalisches institut der universität bonn, bonn, germany b panjab university, department of physics, chandigarh, india calabria university, physics department and infn, cosenza, italy a national centre for particle physics, universiti malaya, kuala lumpur, malaysia c the henryk niewodniczanski institute of nuclear physics, polish academy of sciences, krakow, poland d agh-university of science and technology, faculty of physics and applied computer science, krakow, poland d department of physics, jagellonian university, cracow, poland deutsches elektronen-synchrotron desy, hamburg, germany deutsches elektronen-synchrotron desy, zeuthen, germany school of physics and astronomy, university of glasgow, glasgow, united kingdom e hamburg university, institute of experimental physics, hamburg, germany f institute of particle and nuclear studies, kek, tsukuba, japan g institute of physics and technology of ministry of education and science of kazakhstan, almaty, kazakhstan institute for nuclear research, national academy of sciences, kyiv, ukraine department of nuclear physics, national taras shevchenko university of kyiv, kyiv, ukraine department of physics, mcgill university, montréal, québec, canada h a t h meiji gakuin university, faculty of general education, yokohama, japan g lomonosov moscow state university, skobeltsyn institute of nuclear physics, moscow, russia i max-planck-institut für physik, münchen, germany department of physics, university of oxford, oxford, united kingdom e infn padova, padova, italy a dipartimento di fisica dell’ università and infn, padova, italy a polytechnic university, tokyo, japan g dipartimento di fisica, università ‘la sapienza’ and infn, rome, italy a raymond and beverly sackler faculty of exact sciences, school of physics, tel aviv university, tel aviv, israel j department of physics, tokyo institute of technology, tokyo, japan g università di torino and infn, torino, italy a università del piemonte orientale, novara, and infn, torino, italy a ii department of physics, university of toronto, toronto, ontario, canada m s a h physics and astronomy department, university college london, london, united kingdom e faculty of physics, university of warsaw, warsaw, poland national centre for nuclear research, warsaw, poland department of particle physics and astrophysics, weizmann institute, rehovot, israel department of physics, york university, ontario, canada m j p h a supported by the italian national institute for nuclear physics (infn) b supported by the german federal ministry for education and research (bmbf), under contract no. h pdf c supported by hir grant um.c/ / /hir/ and umrg grants ru - , rp a- afr and rp b- afr from universiti malaya, and ergs grant er - a from the ministry of education, malaysia d supported by the national science centre under contract no. dec- / /m/st / e supported by the science and technology facilities council, uk f supported by the german federal ministry for education and research (bmbf), under contract no. h guf, and the sfb of the deutsche forschungsge- meinschaft (dfg) g supported by the japanese ministry of education, culture, sports, science and technology (mext) and its grants for scientific research h supported by the natural sciences and engineering research council of canada (nserc) i supported by rf presidential grant n . . for the leading scientific schools and by the russian ministry of education and science through its grant for scientific research on high energy physics j supported by the israel science foundation iii a also funded by max planck institute for physics, munich, germany b also funded by max planck institute for physics, munich, germany, now at sri guru granth sahib world university, fatehgarh sahib c also at agensi nuklear malaysia, kajang, bangi, malaysia d also at cracow university of technology, faculty of physics, mathematics and ap- plied computer science, poland e partially supported by the polish national science centre projects dec- / /b/st / and dec- / /b/st / f now at rockefeller university, new york, ny , usa g now at university of liverpool, united kingdom h also affiliated with university college london, uk i supported by the alexander von humboldt foundation j now at cern, geneva, switzerland k also at institute of theoretical and experimental physics, moscow, russia l alexander von humboldt professor; also at desy and university of oxford m also at university of tokyo, japan n now at kobe university, japan o supported by desy, germany p member of national technical university of ukraine, kyiv polytechnic institute, kyiv, ukraine q now at desy atlas group r member of national university of kyiv - mohyla academy, kyiv, ukraine s now at bnl, usa t now at lnf, frascati, italy u also at max planck institute for physics, munich, germany, external scientific mem- ber v now at tokyo metropolitan university, japan w also supported by desy x also at Łódź university, poland y member of Łódź university, poland z now at polish air force academy in deblin aa now at university of the punjab, lahore, pakistan ab deceased iv introduction the measurement of beauty and charm production in ep collisions at hera is an im- portant testing ground for perturbative quantum chromodynamics (pqcd), since the heavy-quark masses provide a hard scale that allows perturbative calculations to be made. at leading order, the dominant process for heavy-quark production at hera is boson- gluon fusion (bgf). in this process, a virtual photon emitted by the incoming electron interacts with a gluon from the proton forming a heavy quark–antiquark pair. when the negative squared four-momentum of the virtual photon, q , is large compared to the pro- ton mass, the interaction is referred to as deep inelastic scattering (dis). for heavy-quark transverse momenta comparable to the quark mass, next-to-leading-order (nlo) qcd calculations based on the dynamical generation of the massive quarks [ – ] are expected to provide reliable predictions. beauty and charm production in dis has been measured using several methods by the h [ – ] and zeus [ – ] collaborations. all but the two most recent measurements of charm production [ , ] and older data [ ] have been combined [ ]. predictions from nlo qcd describe all results reasonably well. inclusive jet cross sections in beauty and charm events are used in the analysis presented here to extract the heavy-quark contribution to the proton structure function f with high precision, and to measure related qcd parameters. for this purpose, the long lifetimes of the weakly decaying b and c hadrons, which make the reconstruction of their decay vertices possible, as well as their large masses were exploited. two discriminating variables, the significance of the reconstructed decay length and the invariant mass of the charged tracks associated with the decay vertex (secondary vertex), were used. this inclusive tagging method leads to a substantial increase in statistics with respect to previous zeus measurements. differential cross sections as a function of q , the bjorken scaling variable, x, jet transverse energy, e jet t , and pseudorapidity, η jet, were measured. they are compared to a leading- order (lo) plus parton-shower (ps) monte carlo prediction and to nlo qcd calculations. the beauty and charm contributions to the proton structure function f , denoted as f bb̄ and f cc̄ , respectively, as well as beauty and charm reduced cross sections (σ bb̄ r and σ cc̄ r , respectively) were extracted from the double-differential cross section as a function of q and x. the results are compared to previous measurements and to predictions from perturbative qcd. the running ms beauty-quark mass, mb at the scale mb, denoted mb(mb), is measured using σbb̄r , following a procedure similar to that used for a recent extraction of the charm- quark mass [ ]. this represents the first measurement of the b-quark mass using hera or any other hadron collider data. experimental set-up this analysis was performed with data taken with the zeus detector from to , when hera collided electrons with energy ee = . gev with protons of energy gev, corresponding to a centre-of-mass energy √ s = gev. this data-taking period is denoted as hera ii. the corresponding integrated luminosity is ( ± ) pb− . a detailed description of the zeus detector can be found elsewhere [ ]. a brief outline of the components that are most relevant for this analysis is given below. in the kinematic range of the analysis, charged particles were tracked in the central tracking detector (ctd) [ – ] and the microvertex detector (mvd) [ ]. these components operated in a magnetic field of . t provided by a thin superconducting solenoid. the ctd consisted of cylindrical drift-chamber layers, organised in nine superlayers covering the polar-angle region ° < θ < °. the mvd silicon tracker consisted of a barrel (bmvd) and a forward (fmvd) section. the bmvd contained three layers and provided polar-angle coverage for tracks from ° to °. the four-layer fmvd extended the polar- angle coverage in the forward region to °. after alignment, the single-hit resolution of the mvd was µm. the transverse distance of closest approach (dca) of tracks to the nominal vertex in x–y was measured to have a resolution, averaged over the azimuthal angle, of ( ⊕ /pt ) µm, with pt in gev. for ctd-mvd tracks that pass through all nine ctd superlayers, the momentum resolution was σ(pt )/pt = . pt ⊕ . ⊕ . /pt , with pt in gev. the high-resolution uranium–scintillator calorimeter (cal) [ – ] consisted of three parts: the forward (fcal), the barrel (bcal) and the rear (rcal) calorimeters. each part was subdivided transversely into towers and longitudinally into one electromagnetic section (emc) and either one (in rcal) or two (in bcal and fcal) hadronic sections (hac). the smallest subdivision of the calorimeter was called a cell. the cal energy res- olutions, as measured under test-beam conditions, were σ(e)/e = . / √ e for electrons and σ(e)/e = . / √ e for hadrons, with e in gev. the luminosity was measured using the bethe-heitler reaction ep → eγp by a luminosity detector which consisted of independent lead–scintillator calorimeter [ – ] and magnetic spectrometer [ ] systems. in this paper “electron” is used to denote both electron and positron. the zeus coordinate system is a right-handed cartesian system, with the z axis pointing in the nominal proton beam direction, referred to as the “forward direction”, and the x axis pointing towards the centre of hera. the coordinate origin is at the centre of the ctd. the pseudorapidity is defined as η = − ln ( tan θ ) , where the polar angle, θ, is measured with respect to the z axis. monte carlo simulations to evaluate the detector acceptance and to provide predictions of the signal and back- ground distributions, monte carlo (mc) samples of beauty, charm and light-flavour events were generated, corresponding to eighteen, three and one times the integrated luminos- ity of the data, respectively. the rapgap . mc program [ ] in the massive mode (mb = . gev, mc = . gev) was used to generate the beauty and charm samples, where the cteq l [ ] parameterisation for the proton parton density functions (pdfs) was used. in rapgap, lo matrix elements are combined with higher-order qcd radi- ation simulated in the leading-logarithmic approximation. higher-order qed effects are included through heracles . [ ]. light-flavour mc events were extracted from an inclusive dis sample generated with djangoh . [ ] interfaced to ariadne . [ ]. the cteq d [ ] pdfs were used and quarks were taken to be massless. fragmentation and particle decays were simulated using the jetset/pythia model [ , ]. the bowler parameterisation [ ] of the fragmentation function, as implemented in pythia [ ], was used for the heavy-flavour samples. the generated events were passed through a full simulation of the zeus detector based on geant . [ ]. the final mc events were then subjected to the same trigger requirements and processed by the same reconstruction program as the data. for the acceptance determination, the e jet t and η jet distributions in the charm mc, as well as the q distributions in both the beauty and charm mcs, were reweighted in order to give a good description of the data. the charm branching fractions and fragmentation fractions were adjusted to the world-average values [ , ]. theoretical predictions and uncertainties next-to-leading-order qcd predictions for differential cross sections were obtained from the hvqdis program [ ]. the calculations were used to extrapolate the visible cross sections to extract f bb̄ , f cc̄ , σ bb̄ r and σ cc̄ r (see section ). the calculations are based on the fixed-flavour-number scheme (ffns) in which only light flavours are present in the proton and heavy quarks are produced in the interaction [ ]. therefore, the -flavour ( -flavour) ffns variant of the zeus-s nlo qcd fit [ ] was used for the proton pdf for the predictions of the charm (beauty) cross sections. as in the pdf fit, the value of αs(mz) was set to . and the heavy-quark masses (pole masses) were set to mb = . gev and mc = . gev. the renormalisation and factorisation scales, µr and µf , were chosen to be equal and set to µr = µf = √ q + m b(c) . the systematic uncertainty on the theoretical predictions with the zeus-s pdfs were estimated by varying the quark masses and the renormalisation and factorisation scales. quark masses of mb = . and . gev, mc = . and . gev were used. the scales µr, µf were varied independently by a factor of two up and down. additionally, the experimental uncertainties of the data used in the pdf fit were propagated to the predicted cross sections. the total uncertainties were obtained by adding positive and negative changes to the cross sections in quadrature. this results in total uncertainties of – % for beauty and – % for charm. predictions were also obtained using the - and -flavour variants of the abkm nlo pdfs [ ] for the proton. the pole masses of heavy quarks were set to mb = . gev and mc = . gev, both in the pdf fit and in the hvqdis calculation. the values of αs(µr) were provided by lhapdf [ , ] to ensure that the same function was used as in the pdf fit. the renormalisation and factorisation scales were both set to µr = µf = √ q + m b(c) . the nlo qcd predictions are given for parton-level jets. these were reconstructed using the kt clustering algorithm [ ] with a radius parameter r = . in the longitudinally invariant mode [ ]. the e-recombination scheme, which produces massive jets whose four-momenta are the sum of the four-momenta of the clustered objects, was used. the parton-level cross sections were corrected for jet hadronisation effects to allow a direct comparison with the measured hadron-level cross sections: σhad, nlo = chadσparton,nlo , ( ) where the correction factors, chad = + ∆had, were derived from the rapgap mc simu- lation. the factors chad are defined as the ratio of the hadron-level jet to the parton-level jet cross sections, and the parton level is defined as the result of the parton-showering stage of the simulation. since chad were derived from an lo plus parton shower mc, but are applied to an nlo prediction, the uncertainty on chad cannot be estimated in a straightforward way. within the framework of parton showering, mc subsets with different numbers of radiated partons were investigated using rapgap and pythia samples. these studies indicated that different approaches yield variations of ∆had of typically a factor of two. since it is not clear if the variations can be interpreted as uncertainties on chad, no such uncertainties were included in the cross-section (f ) predictions. however, for the extraction of the b-quark mass, such a theoretical uncertainty needs to be included. data selection events containing a scattered electron were selected online by means of a three-level trigger system [ , ]. the trigger [ ] did not require the presence of a secondary vertex nor of a jet. offline, the scattered electron was reconstructed using an electron finder based on a neural network [ ]. the hadronic system was reconstructed from energy-flow objects (efos) [ , ] which combine the information from calorimetry and tracking, corrected for energy loss in the detector material. the kinematic variables used in the cross-section measurements, q and x, were reconstructed using the double-angle method [ ]. the following cuts were applied to select a clean dis sample: • the reconstructed scattered electron [ , ] was required to have an energy e′e > gev; • the impact position of the scattered electron on the face of the rcal had to be outside the region × cm centred on x = y = ; • the primary vertex had to be within ± cm in z of the nominal interaction point; • the photon virtuality, q , had to be within < q < gev ; • yjb > . , where yjb is the inelasticity reconstructed using the jacquet-blondel method [ ]; • ye < . , where ye is the inelasticity reconstructed using the electron method [ ]; • < (e − pz) < gev, where (e − pz) = ∑ i (ei − pz,i) and i runs over all final- state particles with energy ei and z-component of momentum pz,i; this selects fully contained neutral-current ep events for which e − pz = ee. jets were reconstructed from efos using the kt clustering algorithm [ ] as was described for parton-level jets in section . jets containing the identified scattered electron were not considered further. events were selected if they contained at least one jet within the pseudorapidity range − . < ηjet < . and with transverse energy, ejett , of e jet t = p jet t ejet pjet > ( . ) gev for beauty (charm), where ejet, pjet and p jet t are the jet energy, momentum and transverse momentum. the cut on e jet t was optimised separately for beauty and charm measure- ments. for beauty, a cut of e jet t > gev ensures a good correlation of reconstructed and hadron-level jets; for charm this cut was . gev to reduce the extrapolation uncertainties for the f cc̄ and σ cc̄ r measurements at low q . in order to reconstruct potential secondary vertices related to b- and c-hadron decays, tracks were selected if: • they had a transverse momentum pt > . gev; • the total number of hits on the track in the mvd was ≥ . each mvd layer provided two coordinate measurements. • if the track was inside the ctd acceptance, track recognition in the ctd was re- quired; the percentage of the tracks used for vertexing with no ctd hits was . %. tracks were associated with the closest jet if they fulfilled the criterion ∆r < with ∆r = √ (ηtrk − ηjet) + (φtrk − φjet) . if two or more of such tracks were associated with the jet, a candidate vertex was fitted from the selected tracks using a deterministic annealing filter [ – ]. this fit provided the vertex position and its error matrix as well as the invariant mass, mvtx, of the charged tracks associated with the reconstructed vertex. the charged-pion mass was assumed for all tracks when calculating the vertex mass. vertices with χ /ndf < , a distance from the interaction point within ± cm in the x–y plane, ± cm in the z direction, and < mvtx < gev were kept for further analysis. the mc gives a good description of the track efficiencies, except for a small fraction of tracks that are affected by hadronic interactions in the detector material between the interaction point and the ctd. efficiency corrections for this effect were determined from a study of exclusive ep → eρ p events [ ], using a special track reconstruction. the number of the pions from the ρ decay that were reconstructed in the mvd alone and had no extension in the ctd was measured. the resulting track efficiency correction in the mc was applied by randomly rejecting selected vertex tracks before the vertex fit, with a probability that depends on the track parameters (around % at η = and pt = gev). extraction of the heavy-flavour cross sections using the secondary-vertex candidates associated with jets, the decay length, d, was defined as the vector in x–y between the secondary vertex and the interaction point projected onto the jet axis in the x–y plane. the sign of the decay length was assigned using the axis of the jet to which the vertex was associated; if the decay-length vector was in the same hemisphere as the jet axis, a positive sign was assigned to it, otherwise the sign of the decay length was negative. negative decay lengths, which originate from secondary vertices reconstructed on the wrong side of the interaction point with respect to the direction of the associated jets, are unphysical and caused by detector resolution effects. a small smearing correction [ ] to the mc decay-length distribution was applied in order to reproduce the data with negative values of decay length. the beauty and charm content in the selected sample was determined using the shape of the decay-length significance distribution together with the secondary-vertex mass dis- tribution, mvtx. the decay-length significance, s, is defined as d/δd, where δd is the uncertainty on d. the invariant mass of the tracks fitted to the secondary vertex provides in the x–y plane, the interaction point was defined as the centre of the beam ellipse, determined using the average primary vertex position for groups of a few thousand events, taking into account the difference in angle between the beam direction and the z direction. the z coordinate was taken as the z position of the primary vertex of the event. a distinguishing variable for jets from b and c quarks, reflecting the different masses of the b and c hadrons. figure shows the decay-length significance, s, for e jet t > . gev divided into four bins: < mvtx < . gev, . < mvtx < gev, < mvtx < gev and no restriction on mvtx. the mc simulation provides a good description of the data. the separation into subsamples is described below. the contents of the negative bins of the significance distribution, n(s−), were subtracted from the contents of the corresponding positive bins, n(s+), yielding a subtracted decay- length significance distribution. in this way, the contribution from light-flavour quarks is minimised. an additional advantage of this subtraction is that symmetric systematic effects, which might arise from discrepancies between the data and the mc, are removed. in order to reduce the contamination of tracks originating from the primary vertex, a cut of |s| > was applied. to extract the contributions from beauty, charm and light flavours in the data sample, a binned χ fit of the subtracted significance distribution in the region < |s| < was performed simultaneously for three mass bins [ ]: < mvtx < . gev; . < mvtx < gev; < mvtx < gev. all mc distributions were normalised to the integrated luminosity of the data before the fit. the overall mc normalisation was constrained by requiring it to be consistent with the normalisation of the data in the significance distribution with |s| < and < mvtx < gev. the fit yielded scaling factors kb, kc and klf for the beauty, charm and light-flavour contributions, respectively, to obtain the best description of the data. the correlation coefficients were as follows: ρb,c = − . (− . ), ρb,lf = . ( . ) and ρc,lf = − . (− . ) for ejett > . ( . ) gev. the subtracted and fitted distributions for e jet t > . gev are shown in fig. . a good agreement between data and mc is observed. the first two mass bins corresponding to the region < mvtx < gev are dominated by charm events. in the third mass bin, beauty events are dominant at high values of significance. the fit procedure was repeated for every bin of a given observable to obtain differential cross sections. for the beauty cross-section extraction, the fit procedure was repeated with the higher cut on e jet t , e jet t > gev. control distributions of e jet t , η jet, log q and log x are shown in fig. after beauty enrichment cuts ( < mvtx < gev and |s| > ) for ejett > . gev and in fig. after charm enrichment cuts ( < mvtx < gev and |s| > ) for ejett > . gev. all data distributions are reasonably well described by the mc. the differential cross sections for jet production in beauty or charm events, q = b, c, corrected to qed born level, in a bin i of a given observable, y , are given by: dσjetq dyi = kq(yi) nhad,mcq (yi) l · ∆yi crad , ( ) where ∆yi is the width of the bin, kq denotes the scaling factor obtained from the fit, nhad,mcq is the number of generated jets in beauty or charm events at the mc hadron level, crad is the qed radiative correction and l is the corresponding integrated luminosity. hadron-level jets were obtained by running the kt clustering algorithm on all stable final- state particles, in the same mode as for the data. weakly decaying b and c hadrons were treated as stable particles and were decayed only after the application of the jet algorithm. the predictions from the hvqdis program are given at the qed born level with a running coupling, αem. hence, a correction of the measured cross sections for qed radiative effects is necessary in order to be able to compare them directly to the hvqdis predictions. the corrections were obtained using the rapgap monte carlo as crad = σrad/σborn, where σrad is the cross section with full qed corrections, as used in the standard mc samples, and σborn was obtained with the qed corrections turned off but keeping αem running. both cross sections, σrad and σborn, were obtained at the hadron level. systematic uncertainties the systematic uncertainties were evaluated by varying the analysis procedure or by chan- ging the selection cuts and repeating the extraction of the cross section. the following sources of experimental systematic uncertainties were identified [ , ]; the uncertainties on the integrated cross sections determined for each source are summarised in table to indicate the sizes of the different effects: δ dis selection – the cuts for dis event selection were varied in both data and mc. the cut on the scattered electron energy was varied between < e′e < gev (δ ee ), the cut on the inelasticity was varied between . < yjb < . (δ y ), and the lower cut on e − pz was changed by ± gev (δe−pz ); δ trigger efficiency – the uncertainty on the trigger efficiency was evaluated by comparing events taken with independent triggers; δ tracking efficiency correction – the size of the correction was varied by its estimated uncertainty of ± %; δ decay-length smearing – the fraction of secondary vertices for which the decay length was smeared was varied separately in the core (δcore ) and the tails (δ tail ) of the distri- bution such that the agreement between data and mc remained reasonable; δ signal extraction procedure – the systematic uncertainty on the signal extraction pro- cedure was estimated by changing the lower |s| cut from |s| > to |s| > and |s| > ; δ jet energy scale – the calorimetric part of the transverse jet energy in the mc was varied by its estimated uncertainty of ± %; δ electron energy scale – the reconstructed energy of the scattered electron was varied in the mc by its estimated uncertainty of ± %; δ mc model dependence – the q (δ q ), η jet (δ ηjet ) and e jet t (δ e jet t ) reweighting corrections in the charm mc were varied in a range for which the description of data by mc remained reasonable. the same relative variations were applied to the beauty mc; δ light-flavour background – the light-flavour contribution to the subtracted significance distribution includes a contribution from long-lifetime strange-hadron decays. to es- timate the uncertainty due to modelling of this effect, the mc light-flavour distribution of n(s+) − n(s−) was scaled by ± % [ ] and the fit was repeated; δ charm fragmentation function – to estimate the sensitivity to the charm fragmentation function, it was changed in the mc from the bowler to the peterson [ ] parameterisa- tion with ǫ = . [ ]; δ beauty fragmentation function – to estimate the sensitivity to the beauty fragmentation function, it was changed in the mc from the bowler to the peterson parameterisation with ǫ = . [ ]; δ charm branching fractions (δ br ) and fragmentation fractions (δ frag ) – these were varied within the uncertainties of the world-average values [ , , ]; δ luminosity measurement – a . % overall normalisation uncertainty was associated with the luminosity measurement. to evaluate the total systematic uncertainty on the integrated cross sections, the contri- butions from the different systematic uncertainties were added in quadrature, separately for the negative and the positive variations. the same procedure was applied to each bin for the differential cross sections. however, the luminosity measurement uncertainty was not included. in the case of beauty, the dominant effects arise from the uncertainties on the track-finding inefficiencies, the beauty fragmentation function and mc modelling. for charm, the uncertainties on the branching fractions, the light-flavour asymmetry as well as on the mc modelling contribute most to the total systematic uncertainty. cross sections cross sections for inclusive jet production in beauty (charm) events were measured in the range e jet t > ( . ) gev, − . < ηjet < . for dis events with < q < gev and . < y < . , where the jets are defined as in section . the single-differential cross sections for jet production in beauty and charm events were measured as a function of e jet t , η jet, q and x. the results of the measured cross sections are given in tables – and shown in figs. – . the measurements are compared to the hvqdis nlo qcd predictions obtained using zeus-s and abkm as proton pdfs, and to the rapgap predictions scaled by a factor of . for beauty and . for charm. the scale factors correspond to the ratio of the measured integrated visible cross section to the rapgap prediction. the shapes of all measured beauty cross sections are reasonably well described by hvqdis and the rapgap mc. rapgap provides a worse description of the shape of the charm cross sections than hvqdis. for charm, the data are typically – % above the hvqdis nlo prediction, but in reasonable agreement within uncertainties. differences between the nlo predictions using the different proton pdfs are mostly very small. double-differential cross sections as a function of x for different ranges of q for inclusive jet production in beauty and charm events are listed in tables and , respectively. extraction of f qq̄ and σqq̄ r the heavy-quark contribution to the proton structure function f , f qq̄ with q = b, c, can be defined in terms of the inclusive double-differential cross section as a function of x and q , d σqq̄ dx dq = πα em xq { [ + ( − y )]f qq̄ (x, q ) − y f qq̄ l (x, q ) } , where f qq̄ l is the heavy-quark contribution to the structure function fl. to extract f qq̄ from the visible jet production cross sections in heavy-quark events, meas- ured in bins of x and q , an extrapolation from the measured range in e jet t and η jet to the full kinematic phase space was performed. this implicitly takes into account the jet multiplicity. the measured values of f qq̄ at a reference point in the x–q plane were calculated using f qq̄ (x, q ) = d σjetq /dx dq d σ had,nlo q /dx dq f qq̄,nlo (x, q ) , ( ) where d σjetq /dx dq is determined in analogy to eq. ( ), and f qq̄,nlo and d σhad,nloq /dx dq were calculated at nlo in the ffns using the hvqdis program with the factor chad applied as in eq. ( ). the proton pdfs were obtained from the ffns variant of the herapdf . nlo qcd fit [ ]. this pdf was used in order to be consistent with the hera combined results [ ]. the strong coupling constant αs(mz) was set to . as in the pdf fit. other settings were as described in section for the zeus-s variant. as discussed in section , d σjetq /dx dq was multiplied by /cradq , hence f qq̄ is given at qed born level, consistent with the usual convention. the procedure of eq. ( ) also corrects for the f qq̄ l contribution to the cross section. this assumes that the calculation correctly predicts the ratio f qq̄ l /f qq̄ . for the acceptance corrections, the monte carlo was reweighted as discussed in section . the extrapolation factors for beauty due to cuts on e jet t and η jet typically range from . to . , decreasing with increasing q . the factor is up to . at high values of x. for charm, the extrapolation factors are typically about in the region < q < gev and about in the region < q < gev . the uncertainty on the extrapolation from the measured range to the full kinematic phase space was estimated by varying the paramet- ers of the calculation for the extrapolation factors and adding the resulting uncertainties in quadrature. for charm, the same variations were performed as for the hera com- bined results [ ]: the charm mass was varied by ± . gev; the strong coupling constant αs(mz) was changed by ± . ; renormalisation and factorisation scales were multiplied simultaneously by . or . uncertainties resulting from the proton pdf uncertainty are small [ ] and were neglected. for beauty, the same variations of αs and scales were made and the beauty mass was varied by ± . gev. for each bin, a reference point in x and q was defined (see table ) to calculate the structure function. in addition, beauty and charm reduced cross sections were determined. they are defined as σqq̄r = d σqq̄ dx dq · xq πα em[ + ( − y )] = f qq̄ (x, q ) − y + ( − y ) f qq̄ l (x, q ) , and are extracted in analogy to f qq̄ as described above except that no assumption on f qq̄ l is required. the extracted values of f bb̄ and f cc̄ are given in tables and , respectively, while σ bb̄ r and σcc̄r are shown in tables and . the total uncertainties of the measurements were calculated from the statistical and systematic uncertainties of the measured cross sections (tables , , – ) and of the extrapolation uncertainty (tables – ), added in quadrature. the structure function f cc̄ is shown in fig. as a function of x for different values of q . the measurements are compared to the nlo qcd herapdf . [ ] predictions, the most recent official release of the herapdf, based on the rt [ ] general-mass variable- flavour-number scheme (gmvfns). the predictions are consistent with the measure- ments. in fig. , the measured σcc̄r values are compared to the hera combined results [ ] as well as to the two recent results from zeus [ , ] which are not yet included in the combination. for the comparison, some of the measured values of this analysis were swum in q and x using hvqdis. this measurement is competitive, especially at high q , where the extrapolation uncertainty is low, and is in agreement with the hera combined measurements. the structure function f bb̄ is shown in fig. as a function of x for different values of q . the measurements are compared to herapdf . gmvfns predictions. the increase in the uncertainty on the prediction around q = m b is a feature of the gmvfns scheme used. the predictions are consistent with the measurements. the f bb̄ measurement is also shown as a function of q for fixed x in fig. , and is compared to previous zeus and h measurements. again, hvqdis was used to swim the measured values in q and x to match the previous measurements. in a wide range of q , this measurement represents the most precise determination of f bb̄ at hera. it is in good agreement with the previous zeus analyses and h measurements. several nlo and nnlo qcd predictions based on the fixed- or variable-flavour-number schemes [ – ] are also compared to the measurements. predictions from different theoretical approaches agree well with each other. all predictions provide a reasonable description of the data. measurement of the running beauty-quark mass the reduced beauty cross sections, σbb̄r , (fig. and table ) together with inclusive dis data were used to determine the beauty-quark mass, in a simultaneous fit of the mass and the parton densities. the measurement procedure follows closely the method presented in a recent h -zeus publication [ ], where the running charm-quark mass in the ms scheme was extracted using a simultaneous qcd fit of the combined hera i inclusive dis data [ ] and the hera combined charm dis data [ ]. this approach was also used and extended by a similar independent analysis [ ], and was preceded by a similar analysis of a partial charm data set [ ]. the fit for the running beauty-quark mass was performed within the herafitter [ ] framework choosing the abm implementation of the fixed-flavour-number scheme at next- to-leading order [ , , , , ]. the openqcdrad [ ] option in herafitter was used in the ms running-mass mode. the fit was applied to the beauty data listed in table and to the same inclusive dis data as in the charm-quark mass fit [ ]. a fit to the inclusive data only does not show any significant dependence on mb. in order to avoid technical complications, no charm data were included in the simultaneous fit and only mb was extracted. the pdfs resulting from the simultaneous fit changed only marginally with respect to the nominal pdfs obtained from the fit to the inclusive dis data only. the χ of the qcd fit, including the beauty data, shows a clear dependence on the beauty-quark mass, mb, as can be seen in fig. . the total χ for the best fit is for degrees of freedom, and the partial contribution from the beauty data is . for points. the beauty-quark mass and its uncertainty are determined from a parabolic parameterisation. the best fit yields mb(mb) = . ± . (fit)+ . − . (mod.)+ . − . (param.) + . − . (theo.) gev for the ms running beauty-quark mass at nlo. the fit uncertainty (fit) is determined from ∆χ = . it contains the experimental uncertainties, the extrapolation uncertainties, the uncertainties of the standard pdf parameterisation, as well as an estimate of the uncertainty on the hadronisation corrections, as detailed below. in addition, the result has uncertainties attributed to the choices of some extra model parameters (mod.), some additional variations of the pdf parameterisation (param.) and uncertainties on the perturbative qcd parameters (theo.). details of the uncertainty evaluation include: fit uncertainty: for the beauty data, all uncertainties from tables , (experimental) and (extrapolation), and the statistical uncertainty, as summarised in table , were accounted for in the fit. following the discussion in section , an uncertainty of % on ∆had = chad − (table ) was introduced as an additional uncorrelated uncertainty. the uncertainties arising from the default pdf parameterisation [ ], including the so-called “flexible” gluon parameterisation, are implicitly part of the fit uncertainty. the statistical uncertainties and the uncertainties δ , δ , δ core , δ and δ from tables and were treated as uncorrelated, while all other uncertainties, including those from luminosity and from table , were treated as point-to-point correlated. the “multiplicative” uncertainty option [ ] from herafitter was used. in the case of asymmetric uncertainties, the larger was used in both directions. the uncertainties of the inclusive data were used as published. since the inclusive data were taken during the hera i phase and the beauty data during the hera ii phase, the two sets of data were treated as uncorrelated. model uncertainty: the model choices include an assumption on the strangeness frac- tion, fs, the minimum q used in the data selection, q min, and q , the starting value for the qcd evolution. these were treated exactly as in the charm-quark mass fit [ ]. table lists the choices and variations and their individual contribu- tions to the model uncertainty attributed to the model choices. another source of uncertainty is that the b-quark mass was used earlier to extrapolate the measured visible cross sections to the reduced cross sections. the corresponding uncertainty is parameterised in table and used in the fit, but the correlation of this uncertainty with the mass used in the qcd fit is lost. since the hvqdis [ ] program used for the extrapolation uses the pole-mass scheme, and no differential calculations are available in the running-mass scheme, no fully consistent treatment of this correlation is possible. however, the equivalent uncertainty when using the pole-mass scheme can be consistently estimated. for this purpose, the fit was re- peated with the pole-mass option of openqcdrad, which was checked to yield results consistent with the hvqdis predictions for σbb̄r . for the charm-quark mass fit [ ] this uncertainty was denoted “exp”. the result, mb(pole) = . ± . (fit) gev, has a fit uncertainty which is the same as the fit uncertainty for the running-mass fit. however, since the pole-mass defin- ition includes an unavoidable additional theoretical uncertainty due to a nonper- turbative contribution, no attempt to extract a pole-mass measurement with full systematic uncertainties was made. to recover the correlation between the extra- polation and the mass fit, the extrapolated cross sections were iteratively modified using the predictions from the mass values obtained in each fit. this removes the uncertainty on mb in the extrapolation and takes the full correlations into account. the resulting mass mb(pole) = . ± . (fit) gev is slightly lower. the difference between the results from the two procedures (δmext = − . gev) was treated as an additional model uncertainty. pdf parameterisation uncertainty: the parameterisation of the pdfs is chosen as for the charm-quark mass fit [ ], including the “flexible” parameterisation of the gluon distribution. an additional uncertainty is estimated by freeing three extra pdf parameters duv , dd̄ and dū in the fit which allow for small shape variations in the uv, ū and d̄ parton distributions [ ]. the effect is given in table . perturbative scheme and related theory uncertainty: the parameters used for the per- turbative part of the qcd calculations also introduce uncertainties; the effects are listed in table . as in previous analyses [ , , ], the ms running-mass scheme [ – ] was chosen for all calculations of the reduced cross sections and the fit because it shows better perturbative convergence behaviour than the pole-mass scheme. in order to allow the low-q points of the inclusive dis measurement to be included without the need of additional charm-quark mass corrections, the number of active flavours (nf) was set to three, i.e. the charm contribution was also treated in the fixed-flavour-number scheme. accordingly, the strong coupling constant was set to αs(mz) nf= = . ± . , corresponding to αs(mz)nf= = . ± . . the theoretical prediction of the charm contribution to the inclusive dis data is obtained using the running charm-quark mass obtained from the fit to the combined hera charm data [ ], i.e. mc(mc) = ( . ± . ) gev. it was checked that, as expected, using this mass together with the central pdf from the mb fit, a good description of the combined hera charm data [ ] was obtained. thus, the charm contribution to the inclusive data should be well described. the renormalisation and factorisation scales were set to µ = µr = µf = √ q + m with m = , mc, mb for the light quark, charm, and beauty contributions, respect- ively, and varied simultaneously by a factor two as in previous analyses [ , ]. the measured beauty-quark mass is in very good agreement with the world average mb(mb) = ( . ± . ) gev [ ]. the resulting predictions for the beauty cross sec- tions are shown together with the data in fig. . figure also shows the change in the predictions resulting from the fit when different mb values are assumed. the largest sensit- ivity to mb arises from the low-q region, while at high q the impact of the beauty-quark mass is small. conclusions inclusive jet production cross sections in events containing beauty or charm quarks have been measured in dis at hera, exploiting the long lifetimes and large masses of b and c hadrons. in contrast to previous analyses at zeus, the measurement was not restricted to any particular final state. this resulted in substantially increased statistics. differential cross sections as functions of e jet t , η jet, q and x were determined. next-to- leading-order qcd predictions calculated using the hvqdis program using two different sets of proton pdfs are consistent with the measurements. the heavy-quark contributions to the proton structure function f as well as beauty and charm reduced cross sections were extracted from the double-differential cross sections as a function of x and q . the f bb̄ , f cc̄ and σ bb̄ r , σ cc̄ r values are in agreement with previous measurements at hera. the results were also compared to several nlo and nnlo qcd calculations, which provide a good description of the data. the precision of the f cc̄ measurement is competitive with other analyses. for a wide range of q , the f bb̄ measurement represents the most precise determination of f bb̄ . the running beauty-quark mass in the ms scheme was determined from an nlo qcd fit in the fixed-flavour-number scheme to the σbb̄r cross sections from this analysis and to hera i inclusive dis data: mb(mb) = . ± . (fit)+ . − . (mod.)+ . − . (param.) + . − . (theo.) gev this value agrees well with the world average. acknowledgements we appreciate the contributions to the construction, maintenance and operation of the zeus detector of many people who are not listed as authors. the hera machine group and the desy computing staff are especially acknowledged for their success in providing excellent operation of the collider and the data-analysis environment. we thank the desy directorate for their strong support and encouragement. it is a pleasure to thank the abkm, cteq, jr and mstw groups that provided the predictions for f bb̄ shown in fig. . we gratefully acknowledge the advice from s. alekhin and r. plačakytė concerning the appropriate usage of openqcdrad and herafitter. references [ ] b.w. harris and j. smith, heavy-quark correlations in deep-inelastic electroproduction, nucl. phys. b ( ) , [arxiv:hep-ph/ ]. 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[ ] particle data group, j. beringer et al., review of particle physics, phys. rev. d ( ) . http://projects.hepforge.org/herafitter http://dx.doi.org/ . /j.physletb. . . http://arxiv.org/abs/ . http://arxiv.org/abs/ . http://www-zeuthen.desy.de/~alekhin/openqcdrad http://dx.doi.org/ . /bf http://dx.doi.org/ . /s - ( ) - http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /s - ( ) - http://arxiv.org/abs/hep-ph/ http://dx.doi.org/ . /physrevd. . source beauty charm (%) (%) δ event and dis selection ± . ± . δ trigger efficiency + . + . δ tracking efficiency ± . ± . δ decay-length smearing ± . ± . δ signal extraction procedure ± . ± . δ jet energy scale ± . ± . δ em energy scale ± . ± . δ charm q reweighting (δ q ,c ) ± . ± . beauty q reweighting (δ q ,b ) ± . ± . charm ηjet reweighting (δ ηjet,c ) + . − . + . − . beauty ηjet reweighting (δ ηjet,b ) + . − . + . − . charm e jet t reweighting (δ e jet t ,c ) + . − . + . − . beauty e jet t reweighting (δ e jet t ,b ) + . − . + . − . δ light-flavour asymmetry ± . ± . δ charm fragmentation function − . + . δ beauty fragmentation function − . + . δ br and fragmentation fractions + . − . + . − . δ luminosity measurement ± . ± . total + . − . + . − . table : effects of the systematic uncertainties on the integrated beauty- and charm-jet cross sections. e jet t dσ jet b /de jet t (pb/gev) c had crad (gev) stat. syst. : ± + − . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . e jet t dσ jet c /de jet t (pb/gev) c had crad (gev) stat. syst. . : ± + − . . : ± + − . . : ± + − . . : . ± . + − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of e jet t . the beauty (charm) cross sections are given for < q < gev , . < y < . , e jet t > ( . ) gev and − . < ηjet < . . the measurements are given together with their statistical and systematic uncertainties. hadronisation and qed radiative corrections, chad and crad, respectively, are also shown. ηjet dσ jet b /dηjet (pb) chad crad stat. syst. − . : − . ± + − . . − . : − . ± + − . . − . : − . ± + − . . − . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . ηjet dσjetc /dη jet (pb) chad crad stat. syst. − . : − . ± + − . . − . : − . ± + − . . − . : − . ± + − . . − . : − . ± + − . . − . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of ηjet. for details, see the caption of table . q dσ jet b /dq (pb/gev ) chad crad (gev ) stat. syst. : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . q dσjetc /dq (pb/gev ) chad crad (gev ) stat. syst. : ± + − . . : ± + − . . : ± . + − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . : . ± . + . − . . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of q . for details, see the caption of table . x dσ jet b /dx (pb) chad crad stat. syst. . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . x dσjetc /dx (pb) c had crad stat. syst. . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . . : . ± + − . . table : differential cross sections for inclusive jet production in beauty events (top) and charm events (bottom) as a function of x. for details, see the caption of table . q x d σ jet b /dx dq (pb/gev ) chad crad (gev ) stat. syst. : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . table : double-differential cross sections for inclusive jet production in beauty events as a function of x for different ranges of q . the cross sections are given for < q < gev , . < y < . , e jet t > gev and − . < ηjet < . . the measurements are given together with their statistical and systematic uncertainties. hadronisation and qed radiative corrections, chad and crad, respectively, are also shown. q x d σjetc /dx dq (pb/gev ) chad crad (gev ) stat. syst. : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . : . : . ± + − . . table : double-differential cross sections for inclusive jet production in charm events as a function of x for different ranges of q . the cross sections are given for < q < gev , . < y < . , e jet t > . gev and − . < ηjet < . . the measurements are given together with their statistical and systematic uncertainties. hadronisation and qed radiative corrections, chad and crad, respectively, are also shown. q x f bb̄ (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : the structure function f bb̄ as a function of x for seven different values of q . the first error is statistical, the second systematic and the last is the extrapolation uncer- tainty. the horizontal lines correspond to the bins in q in table . q x f cc̄ (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : the structure function f cc̄ as a function of x for seven different values of q . the first error is statistical, the second systematic and the last is the extrapolation uncer- tainty. the horizontal lines correspond to the bins in q in table . q x σbb̄r (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : reduced beauty cross sections, σbb̄r , as a function of x for seven different values of q . for more details, see the caption of table . q x σcc̄r (gev ) stat. syst. extr. . . . ± . + . − . + . − . . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . . . ± . + . − . + . − . table : reduced charm cross section, σcc̄r , as a function of x for seven different values of q . for more details, see the caption of table . q x δ ee δ y δ e−pz δ δ δ core δtail δ δ δ ( gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . + . − . + . − . + . − . + . + . − . + . − . − . + . − . + . + . − . − . + . : . : . + . − . − . + . − . + . + . + . − . − . + . − . + . − . + . + . − . − . + . : . : . − . + . + . − . + . − . + . − . + . − . + . + . − . − . + . + . − . − . + . : . : . − . + . − . + . + . − . + . + . − . − . + . − . + . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . + . − . + . − . − . + . − . + . − . + . − . + . : . : . − . + . + . − . − . + . + . + . − . + . − . − . + . + . − . + . − . − . + . : . : . − . + . − . + . − . + . + . + . − . + . − . − . + . + . − . + . − . + . − . : . : . − . + . − . + . + . − . + . + . − . − . + . − . + . + . − . + . − . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . + . − . + . − . + . − . − . + . : . : . + . − . − . + . + . − . + . + . − . + . − . + . − . − . + . − . + . + . − . : . : . − . + . + . − . + . − . + . + . − . − . + . − . + . − . + . + . − . − . + . : . : . − . + . + . − . − . + . − . + . − . − . + . + . − . + . − . + . − . − . + . : . : . − . + . + . − . − . + . + . + . − . − . + . − . + . − . + . + . − . + . − . : . : . − . + . + . − . + . − . + . + . − . − . + . − . + . − . + . + . − . − . + . : . : . − . + . − . + . + . − . + . + . − . + . − . − . + . + . − . + . − . − . + . : . : . + . − . + . − . + . − . + . + . − . − . + . + . − . − . + . − . + . + . − . : . : . − . + . − . + . − . + . + . + . − . − . + . − . + . − . + . + . − . + . − . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in beauty events. see section for more details. q x δ q ,c δ q ,b δ η jet ,c δ η jet ,b δ e jet t ,c δ e jet t ,b δ δ δ δ br δ frag (gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . − . + . + . − . + . − . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . − . + . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . − . + . − . + . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . − . + . − . + . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . − . + . − . + . + . − . − . + . − . + . − . + . + . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . − . + . − . + . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . + . − . + . − . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . − . + . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . + . − . + . − . + . − . : . : . − . + . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . : . : . + . − . + . − . − . + . + . − . − . + . − . + . + . − . − . − . + . − . + . − . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in beauty events (continued). q x δ ee δ y δ e−pz δ δ δ core δtail δ δ δ ( gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . + . − . + . − . − . + . + . + . − . − . + . + . − . + . − . − . + . − . + . : . : . + . − . + . − . − . + . + . + . − . − . + . + . − . + . − . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . − . + . − . + . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . + . − . − . + . − . + . − . + . : . : . + . − . + . − . + . − . + . − . + . − . + . + . − . − . + . − . + . − . + . : . : . − . + . − . + . − . + . + . + . − . − . + . + . − . + . − . − . + . + . − . : . : . − . + . − . + . − . + . + . + . − . − . + . − . + . − . + . − . + . − . + . : . : . − . + . + . − . − . + . + . + . − . − . + . − . + . − . + . − . + . − . + . : . : . + . − . − . + . + . − . + . + . − . − . + . + . − . − . + . − . + . − . + . : . : . − . + . − . + . + . − . + . + . − . − . + . − . + . + . − . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . − . + . + . − . − . + . + . − . : . : . − . + . − . + . + . − . + . − . + . − . + . + . − . − . + . − . + . + . − . : . : . + . − . − . + . − . + . + . + . − . − . + . + . − . + . − . − . + . + . − . : . : . − . + . + . − . + . − . + . + . − . − . + . + . − . + . − . − . + . − . + . : . : . − . + . + . − . − . + . + . − . + . − . + . + . − . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . + . − . − . + . + . − . + . − . + . − . − . + . : . : . − . + . + . − . + . − . + . + . − . − . + . − . + . − . + . + . − . + . − . : . : . − . + . + . − . − . + . + . + . − . + . − . + . − . − . + . − . + . − . + . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in charm events. see section for more details. q x δ q ,c δ q ,b δ η jet ,c δ η jet ,b δ e jet t ,c δ e jet t ,b δ δ δ δ br δ frag ( gev ) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) : . : . + . − . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . − . + . − . + . − . : . : . − . + . + . − . + . − . + . − . − . + . + . − . − . + . − . + . + . − . + . − . : . : . + . − . + . − . + . − . + . − . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . − . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . − . + . + . − . + . − . − . + . + . − . − . + . + . − . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . − . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . + . − . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . + . − . − . + . + . − . − . + . + . + . + . − . + . − . : . : . + . − . + . − . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . + . − . − . + . + . − . − . + . − . + . + . − . − . + . − . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . − . + . + . − . − . + . + . + . + . − . + . − . : . : . − . + . − . + . + . − . − . + . + . − . + . − . − . + . + . + . + . − . + . − . table : systematic uncertainties for the double-differential cross sections of inclusive jet production in charm events (continued). q x δ−mb δ + mb δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . + . − . − . − . . + . − . + . − . − . − . . + . − . + . − . − . − . . + . − . − . − . + . − . . + . − . − . − . + . + . . + . − . + . − . − . − . . + . − . − . − . + . − . . + . − . + . − . + . + . . + . + . + . − . + . − . . + . − . + . − . + . − . . + . + . + . − . + . + . table : extrapolation uncertainties on the structure function f bb̄ due to the variations of the beauty-quark mass, mb, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (down- ward) variation of the corresponding parameter. see section for more details. q x δ−mc δ + mc δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . − . − . + . . + . − . + . − . − . − . . + . + . + . + . + . + . . + . − . − . + . + . + . . + . − . − . − . − . − . . + . − . − . − . − . − . . − . − . − . − . − . − . . + . − . − . + . − . − . . + . − . + . + . − . − . . − . + . + . + . − . + . . + . − . − . + . + . + . . + . + . + . − . + . + . table : extrapolation uncertainties on the structure function f cc̄ due to the variations of the charm-quark mass, mc, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (down- ward) variation of the corresponding parameter. see section for more details. q x δ−mb δ + mb δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . + . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . + . − . − . − . . + . − . + . − . + . − . . + . − . + . − . − . − . . + . − . − . − . + . − . . + . − . − . − . + . + . . + . − . + . − . + . + . . + . − . − . − . + . − . . + . − . + . − . − . + . . + . − . + . − . + . − . . + . − . + . − . + . − . . + . + . + . − . + . + . table : extrapolation uncertainties on the reduced beauty cross section, σbb̄r , due to the variations of the beauty-quark mass, mb, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (downward) variation of the corresponding parameter. see section for more details. q x δ−mc δ + mc δ−µr, µf δ + µr, µf δ−αs δ + αs (gev ) (%) (%) (%) (%) (%) (%) . . + . − . − . + . + . − . . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . + . + . − . . + . − . − . − . − . + . . + . − . + . − . + . + . . + . + . + . + . + . + . . + . − . − . + . + . + . . + . − . − . − . − . − . . + . − . − . − . − . − . . − . − . − . − . − . − . . + . − . − . + . − . − . . + . − . + . − . − . − . . − . + . + . − . + . + . . + . − . − . + . + . + . . + . + . + . − . + . + . table : extrapolation uncertainties on the reduced charm cross section, σcc̄r , due to the variations of the charm-quark mass, mc, factorisation and renormalisation scales, µf and µr, and the strong coupling constant, αs. the plus (minus) superscript indicates the upward (downward) variation of the corresponding parameter. see section for more details. parameter variation uncertainty (gev) fit uncertainty total ∆χ = + . − . model uncertainty fs . + . − . + . − . q min . → . gev + . − . q . → . gev + . − . δmext see text − . total + . − . pdf parameterisation uncertainty duv free in fit + . dd̄ free in fit + . dū free in fit + . total + . − . theory uncertainty mc(mc) ( . ± . ) gev + . − . αs . ± . + . − . µ × , × / + . − . total + . − . table : list of uncertainties for the beauty-quark mass determination. a description of the uncertainties not explicitly mentioned in the text is given elsewhere [ ]. s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s s - - - - e n tr ie s zeus < . gevvtx < m < gevvtx . < m < gevvtx < m vtxno restriction on m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distributions of the decay-length significance, s, for (a) < mvtx < . gev, (b) . < mvtx < gev, (c) < mvtx < gev and (d) no restriction on mvtx. the data are compared to the sum of all mc distributions as well as the individual contributions from the beauty, charm and light-flavour (lf) mc subsamples. all samples were normalised according to the scaling factors obtained from the fit (see text). |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s |s| e n tr ie s zeus < . gevvtx < m < gevvtx . < m < gevvtx < m vtxno restriction on m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distribution of the subtracted decay-length significance in four ranges of mvtx. for more details, see the caption of fig. . (gev) jet te e n tr ie s (gev) jet te e n tr ie s jetη - . - - . . . . e n tr ie s jetη - . - - . . . . e n tr ie s ) /gev (q log . . . e n tr ie s ) /gev (q log . . . e n tr ie s x log - . - - . - - . - - . - e n tr ie s x log - . - - . - - . - - . - e n tr ie s zeus < gev, |s|> vtx < m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distributions of (a) e jet t , (b) η jet, (c) log q and (d) log x of the selected secondary vertices for a beauty-enriched subsample with < mvtx < gev and |s| > . for more details, see the caption of fig. . (gev) jet te e n tr ie s (gev) jet te e n tr ie s jetη - . - - . . . . e n tr ie s jetη - . - - . . . . e n tr ie s ) /gev (q log . . . e n tr ie s ) /gev (q log . . . e n tr ie s x log - . - - . - - . - - . - e n tr ie s x log - . - - . - - . - - . - e n tr ie s zeus < gev, |s|> vtx < m - zeus pb monte carlo lf charm beauty (a) (b) (c) (d) figure : distributions of (a) e jet t , (b) η jet, (c) log q and (d) log x of the selected secondary vertices for a charm-enriched subsample with < mvtx < gev and |s| > . for more details, see the caption of fig. . (gev) jet te ( p b / g e v ) je t t / d e σ d - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep (gev) jet te d a ta / h v q d is . . (gev) jet te ( p b / g e v ) je t t / d e σ d - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep (gev) jet te d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of e jet t . the cross sections are given for < q < gev , . < y < . , e jet t > ( . ) gev and − . < ηjet < . . the data are shown as points. the inner error bars are the statistical uncertainties, while the outer error bars show the statistical and systematic uncertainties added in quadrature. the solid line shows the hvqdis prediction with the zeus-s pdf, corrected for hadronisation effects, with the uncertainties indicated by the band; the dotted line shows the same prediction using the abkm pdf; the dashed line shows the prediction from rapgap scaled to match the measured integrated cross sections. jetη - . - - . . . ( p b ) je t η / d σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep jetη - . - - . . . d a ta / h v q d is . . jetη - . - - . . . ( p b ) je t η / d σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep jetη - . - - . . . d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of ηjet. for more details, see the caption of fig. . ) (gev q ) ( p b / g e v / d q σ d - - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep ) (gev q d a ta / h v q d is . . ) (gev q ) ( p b / g e v / d q σ d - - - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep ) (gev q d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of q . for more details, see the caption of fig. . x - - - - / d x ( p b ) σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x b e b→ep x - - - - d a ta / h v q d is . . x - - - - / d x ( p b ) σ d - zeus pb had c×hvqdis+zeus-s had c×hvqdis+abkm rapgap x . zeus e jet x→x c e c→ep x - - - - d a ta / h v q d is . . (a) (b) figure : differential cross sections for inclusive jet production in (a) beauty events and (b) charm events as a function of x. for more details, see the caption of fig. . . . . . . . . . . . . . . . . . . . . . . x - - - - x - - - - x - - - - c c f . . . . . . . . . - zeus pb herapdf . gmvfns zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : the structure function f cc̄ (filled symbols) as a function of x for seven differ- ent values of q . the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrat- ure. also shown are the nlo qcd herapdf . predictions based on the general-mass variable-flavour-number scheme (solid line and shaded area for the uncertainties). . . . . . . . . . . . . . . . . . . . . . x - - - x - - - x - - - c c r σ . . . . . . . . . zeus = gev q = gev q = gev q = gev q = gev q = gev q = gev q - zeus vtx pb - zeus d* pb - pb+zeus d hera figure : reduced charm cross section, σcc̄r , as a function of x for fixed values of q . results from the current analysis (filled circles) are compared to the zeus d∗± data [ ] (empty triangles), the zeus d+ measurement [ ] (empty squares) and the combination of previous hera results [ ] (empty circles). the inner error bars in the zeus measure- ments show the statistical uncertainties. the inner error bars of the combined hera data represent the uncorrelated part of the uncertainty. the outer error bars include statistical, systematic and theoretical uncertainties added in quadrature. . . . . . . . . . . . . . . . . . x - - - - x - - - - x - - - - b b f . . . . . . . - zeus pb herapdf . gmvfns zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : the structure function f bb̄ (filled symbols) as a function of x for seven differ- ent values of q . the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrat- ure. also shown are the nlo qcd herapdf . predictions based on the general-mass variable-flavour-number scheme (solid line and shaded area for the uncertainties). ) (gev q + . i b b f . . . . . . . . . . . - zeus vtx pb - zeus e pb - pbµzeus - +vtx pbµzeus - h vtx pb herapdf . abkm nnlo mstw nlo mstw nnlo cteq . nlo jr x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= x= . i= figure : the structure function f bb̄ (filled circles) as a function of q for fixed values of x compared to previous results (open squares [ ], open triangles [ ], open circles [ ] and filled squares [ , , ]). the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrature. the data have been corrected to the same reference x as the pre- vious analysis [ ]. the measurements are compared to several nlo and nnlo qcd predictions [ – ]. . . . . . . . . . . . . . . . . . . . . . x - - - x - - - x - - - b b r σ . . . . . . . . . - zeus pb = . gev (best fit) b qcd fit, m = . gev b qcd fit, m = . gev b qcd fit, m zeus = . gev q = gev q = gev q = gev q = gev q = gev q = gev q figure : reduced beauty cross section, σbb̄r , (filled symbols) as a function of x for seven different values of q . the inner error bars are the statistical uncertainty while the outer error bars represent the statistical, systematic and extrapolation uncertainties added in quadrature. also shown are the results of the qcd fit described in section . the central line indicates the best fit, the lower and upper line give the fit for a higher and lower beauty mass, respectively. ) (gev) b (mbm . . . . . . . . . . χ zeus inclusive dis + beauty qcd fit figure : the values of χ for the pdf fit to the combined hera dis data including the beauty measurements, as a function of the running beauty quark mass mb(mb). the ffns abm scheme is used, where the beauty quark mass is defined in the ms scheme. the solid line is a second order polynomial parameterisation of the points. introduction experimental set-up monte carlo simulations theoretical predictions and uncertainties data selection extraction of the heavy-flavour cross sections systematic uncertainties cross sections extraction of f qbarq and rqbarq measurement of the running beauty-quark mass conclusions method detecting facial beauty in periphery running head: discriminating facial beauty in periphery i know you are beautiful even without looking at you: discrimination of facial beauty in peripheral vision kun guo , chang hong liu , and hettie roebuck university of lincoln, uk; and university of hull, uk correspondence chang hong liu, phd department of psychology university of hull, hull hu rx, united kingdom tel: + - - e-mail: c.h.liu@hull.ac.uk core metadata, citation and similar papers at core.ac.uk provided by university of lincoln institutional repository https://core.ac.uk/display/ ?utm_source=pdf&utm_medium=banner&utm_campaign=pdf-decoration-v mailto:c.h.liu@hull.ac.uk detecting facial beauty in periphery abstract prior research suggests that facial attractiveness may capture attention at parafovea. however, little is known about how well facial beauty can be detected at parafoveal and peripheral vision. participants in this study judged relative attractiveness of a face pair presented simultaneously at several eccentricities from the central fixation. the results show that beauty is not only detectable at parafovea but also at periphery. the discrimination performance at parafovea was indistinguishable from the performance around the fovea. moreover, performance was well above chance even at the periphery. the results show that the visual system is able to use the low spatial frequency information to appraise attractiveness. these findings not only provide an explanation for why a beautiful face could capture attention when central vision is already engaged elsewhere, but also reveal the potential means by which a crowd of faces is quickly scanned for attractiveness. keywords: facial attractiveness; fovea; parafovea; peripheral vision detecting facial beauty in periphery beauty is difficult to ignore even when attention is already engaged in a different task. sui and liu ( ) recently demonstrated that a task-irrelevant attractive face presented at parafovea can compete with an ongoing task for spatial attention, suggesting coarse-scale facial information outside the central vision is sufficient for automatic appraisal of facial attractiveness (also see bachmann , for a study of coarse-scale information for facial beauty discrimination at central vision). however, because the face in the sui and liu study was presented at a fixed distance ( . °) from the fixation, it was not clear whether this effect also extends to far parafoveal and even peripheral vision. neither was it clear whether the accuracy of attractiveness discrimination at parafovea is as reliable as in the fovea. here we examined these questions systematically. participants judged relative attractiveness of a face pair presented simultaneously at several eccentricities from the central fixation. it is well known that when a pair of faces is presented, the more attractive face of the two tends to draw greater attention and more inspections (leder et al ; shimojo et al ). in these and other similar studies, researchers have focused on how central vision is engaged in the processing of facial beauty. their results demonstrate that attractive faces tend to dictate preferential eye gaze and fixations, which result in foveation of the preferred face for more detailed information processing. unlike most prior studies, the main interest of the present paper is the discrimination of facial beauty beyond the central vision. given that a vast portion of our visual environment falls outside the foveal region, being able to monitor and assess the visual information and events in the parafoveal and peripheral regions is critical for adaptive reasons. the same ability is also necessary for covert attention where the focus detecting facial beauty in periphery of attention often does not coincide with the high-resolution fovea. prior research has revealed that the ability to discriminate a face identity drops rapidly as a function of eccentricity (mäkelä et al ; melmoth et al ). moreover, past studies have identified a band of middle frequencies (approximately - cycles per face) that is critical for face recognition (bachmann ; costen et al , ; fiorentini et al ; harmon ; harmon and julesz ; peli et al ). however, discrimination or appraisal of facial beauty may require less spatial details than the discrimination of facial identities. there is evidence that low spatial frequency information is often sufficient for discriminating facial beauty or some common facial expressions such as anger and fear presented at the central vision (bachmann ; schyns and oliva ; vuilleumier et al ). perhaps the early stage of attractiveness appraisal can rely on low spatial frequency information that is available at the periphery. to our knowledge, the present study was the first attempt to test this hypothesis at the periphery. to prevent saccadic eye movements to either face image, we presented each face pair on the two sides of the central fixation for a brief ms. the participant’s fixation was monitored by an eye tracker during the task. apart from pairing an attractive face with an unattractive one based on pre-rated scores, we also asked our participants to provide their own attractiveness rating after they had completed the discrimination task. we predicted a stronger effect of eccentricity on discrimination of facial beauty when the difference in attractiveness between two faces is deemed small by participants. detecting facial beauty in periphery method materials the face database was obtained from university of st. andrews. all faces were frontal-view caucasians with neutral expression, and were pre-rated for attractiveness on a -point scale. we chose attractive (mean rating = . , sd = . ) and unattractive (mean rating = . , sd = . ) faces for this study. the chosen faces had no visible facial marks or distinctive hair style (e.g. fringe). the greyscale faces were then cropped to remove external features and to fit within an oval window subtending . × . ° of visual angle, equivalent to the size of a real face shown at a distance during typical conversation (henderson et al ). all images were scaled to a same mean luminance and root-mean-square contrast. each attractive face was randomly paired with an unattractive face. these two faces were then presented bilaterally at equidistance from a central fixation. the three levels of eccentricity (the distance between the inner edge of a face image and the fixation) were °, ° and °, which were chosen to probe foveal, parafoveal and peripheral vision, respectively. each face was used three or four times in different attractive/unattractive combinations to create pairs ( pairs per eccentricity). each pair was presented twice but in a separate block to counterbalance left/right presentation location. this amounted to a total of trials. participants seventeen caucasian participants ( women, mean age = , sd = ) with normal vision viewed the stimulus display binocularly from cm on a chin rest. informed consent was obtained from each participant, and all procedures complied with detecting facial beauty in periphery the world medical association helsinki declaration as revised in october . during the experiment, their fixations were monitored using a video eyetracker toolbox with hz sampling frequency and . ° accuracy (cambridge research systems). the stimulus was presented through a visage graphics system on a gamma-corrected monitor ( × pixels, hz frame rate, mitsubishi) with grey background. procedure each trail started with a warning tune, followed by a -sec central fixation. a pair of faces was then presented for ms. participants were instructed to maintain their fixation and to respond as accurately and as quickly as possible by pressing one of the two buttons to indicate whether the left or right face was more attractive. no feedback was given. the inter-trial interval was . sec. to examine how the participant’s own judgement of attractiveness affects the discrimination performance, all participants also performed a separate, self-paced task where the same face pairs were presented side by side with ° gap in a randomised order. the task was to indicate which face within the pair was more attractive and how different the two faces was in attractiveness on a -point scale ( = slightly different, = very different). the task was always performed after the discrimination task. for these manipulated face images, all participants’ judgements in the rating task were consistent with the answers defined by the pre-rating scores, t( ) = . , p = . . that is, within a face pair, the face with higher pre-rating score in attractiveness was also judged to be more attractive by our participants (mean attractiveness discrimination performance = . %, sd = . ). detecting facial beauty in periphery results in total . % of the trials were excluded from analysis because the eye drifted ° or more away from the central fixation during the face presentation. results in figure a show that the attractiveness discrimination rate was significantly affected by the eccentricity, f( , ) = . , p < . , ηp = . . the performance was indistinguishable for faces presented at ° and ° eccentricity (> %), t( ) = . , p = . . performance at °eccentricity (> %) was significantly lower than these but was clearly above-chance, t( ) = . , p < . . eccentricity had no significant impact on the reaction time data, f( , ) = . , p = . , ηp = . . discrimination performance was also analyzed according to the perceived difference between the attractiveness of two simultaneously presented faces (figure b). there was again a significant main effect of eccentricity, f( , ) = . , p < . , ηp = . . the main effect of perceived attractiveness difference approached the level of significance, f( , ) = . p = . , ηp = . , suggesting an easier discrimination when one face in a pair was clearly more attractive than another. the interaction between the two variables was not significant, f( , ) = . , p = . , ηp = . . again, analysis of the reaction time data did not reveal any significant result. discussion prior research suggests that facial attractiveness may be detectable at parafovea (sui and liu ). our new results show that beauty is not only detectable at parafovea but also at periphery. furthermore, the attractiveness discrimination at parafovea ( °) was indistinguishable from the performance around the fovea ( °). comparing to parafovea, detecting facial beauty in periphery the performance at periphery ( °) was clearly worsened. however, it is remarkable that even here the discrimination performance was still well above-chance. this suggests that our visual system is able to use the low spatial frequency information to perform rapid appraisal of faces for attractiveness. this is consistent with prior observation that physical carriers of facial beauty are originally present in the coarse configural properties of faces (bachmann ). finally, our results show that such a judgment of relative attractiveness at the periphery is sensitive to how much a face is more attractive than the other. discrimination errors appeared to be higher when the perceived difference in attractiveness between the two faces was smaller. this finding suggests that finer discrimination or ranking of facial beauty may require more facial details contained in higher spatial frequencies. the capacity of the peripheral vision may be limited to categorical attractive judgements. these findings not only provide an explanation for why a beautiful face could capture attention when central vision is already engaged elsewhere, but also reveal the potential means by which a crowd of faces is quickly scanned and appraised for attractiveness. it is interesting to note that the participants had little difficulty to appraise two briefly flashed faces very quickly. this means the judgement of relative attractiveness may not require foveation when a face is clearly more attractive than the other. moreover, it means that a quick sampling of attractive faces from a crowd is possible because a relatively small number of fixations would be sufficient if it is unnecessary to foveate on each individual faces. the biological significance of beauty detection may be comparable to some well- studied facial cues such as threatening and fearful expressions that are also known to be detecting facial beauty in periphery detected rapidly at extrafovea (goren and wilson ; leppanen and nelson ). apart from potential danger, our study shows that peripheral vision is also sensitive to potential reward. the visual system may be evolved to rapidly detect attractiveness in the periphery, which may trigger the act of foveation for detailed visual analysis. in other words, an extrafoveal detection of facial beauty may be a precursor for eye gaze, preferential looking, and other deeper visual and attentional processing at the fovea. detecting facial beauty in periphery references bachmann t, “identification of spatially quantised tachistoscopic images of faces: how many pixels does it take to carry identity? ” european journal of cognitive psychology - bachmann t, “when beauty breaks down: investigation of the effect of spatial quantisation on aesthetic evaluation of facial images” perception - costen n p, parker d m, craw i, “spatial content and spatial quantisation effects in face recognition” perception - costen n p, parker d m, craw i, “effects of high-pass and low-pass spatial filtering on face identification” perception & psychophysics - fiorentini a, maffei l, sandim g, “the role of high spatial frequencies in face perception” perception - goren d, wilson h r, “quantifying facial expression recognition across viewing conditions” vision research - harmon l d, “the recognition of faces” scientific american - harmon l d, julesz b, “masking in visual recognition: effects of two-dimensional filtered noise” science - henderson j m, williams c c, falk r j, “eye movements are functional during face learning” memory & cognition - leder h, tinio p p l, fuchs i m, bohrn i, “when attractiveness demands longer looks: the effects of situation and gender” the quarterly journal of experimental psychology - detecting facial beauty in periphery leppanen j m, nelson c a, “tuning the developing brain to social signals of emotions” nature reviews neuroscience - mäkelä p, näsänen r, rovamo j, melmoth d, “identification of facial images in peripheral vision” vision research - melmoth d r, kukkonen h t, mäkelä p k, rovamo j m, “the effect of contrast and size scaling on face perception in foveal and extrafoveal vision” investigative ophthalmology & visual science - peli e, lee e, trempe c l, buzney s, “image enhancement for the visually impaired: the effects of enhancement on face recognition” journal of the optical society of america a-optics & image science - schyns p g, oliva a, “dr. angry and mr. smile: when categorization flexibly modifies the perception of faces in rapid visual presentations” cognition – shimojo s, simion c, shimojo e, scheier c, “gaze bias both reflects and influences preference” nature neuroscience – sui j, liu c h, “can beauty be ignored? effects of facial attractiveness on covert attention” psychonomic bulletin & review - vuilleumier p, armony j l, driver j, dolan r j, “distinct spatial frequency sensitivities for processing faces and emotional expressions” nature neuroscience - detecting facial beauty in periphery figure eccentricity (°) d is cr im in at io n ra te (% ) r ea ct io n tim e (m se c) discrimination rate reaction time a eccentricity (°) d is cr im in at io n ra te (% ) pd= pd= pd= b figure . a. discrimination rate and reaction time for attractive faces as a function of eccentricity. b. influence of perceived difference (pd) in attractiveness on discrimination rate for attractive faces presented at °, ° and ° eccentricities. error bars show standard errors. anal . darren bradley sleeping beauty: a note on dorr’s argument for / darren bradley beauty is about to be drugged, rendering her unconscious for a long time. during that time she will be awakened briefly, either once (on monday) or twice (on monday and tuesday). the number of awakenings depends on the toss of a fair coin: if the result is tails, she is awakened twice: if heads, once. the nature of the drug is that she will not remember being awake. in particular, when she is awakened, she will not know whether it is monday or tuesday. upon awakening on monday, what should her degree of belief be that the coin landed heads? the paradox is that there are compelling arguments for the answers of both / and / . cian dorr gives an argument by analogy that the correct analysis . , july , pp. – . © darren bradley a t u n ive rsity o f c a lifo rn ia , b e rke le y o n a u g u st , h ttp ://a n a lysis.o xfo rd jo u rn a ls.o rg d o w n lo a d e d fro m http://analysis.oxfordjournals.org sleeping beauty: a note on dorr’s argument for / answer is / . i will argue that his analogy is dissimilar in a crucial respect and as such is unhelpful to resolving the problem. dorr presents the following variation on the story( : – ): beauty is about to go to sleep for a long time. during that time she will be awakened briefly, twice, on monday and tuesday. a fair coin will be tossed, and what beauty can remember will depend on the result. if the coin lands tails, she will be given the same amnesia- inducing drug as was used in the original experiment. she will wake up twice, unable to tell if it is the first or second awakening. but if the coin lands heads, she will be given a weaker amnesia-inducing drug, which merely delays the onset of memories from the previous day, rather than destroying them completely. if beauty receives this weaker drug, the first minute of her awakening on tuesday will be just as it would have been if she had received the stronger drug, but after that the memories of monday’s awakening will come flooding back. she will realise that it is tuesday and that the outcome of the toss must have been heads. let p_ be beauty’s credence function immediately after being woken on monday in the variant case. we must assign credence for the following hypotheses: h the coin lands heads and it’s monday h the coin lands heads and it’s tuesday t the coin lands tails and it’s monday t the coin lands tails and it’s tuesday how should this credence be distributed? dorr claims, and i agree, that the only plausible answer is: p_(h ) = p_(t ) = p_(h ) = p_(t ) = / . let p be beauty’s credence function after a minute has passed on monday. assume she has not had the flooding back of memories she would have experienced had h been true, so p(h ) = . nothing in her experi- ence during the first minute does anything to discriminate between the other three hypotheses. so the ratio of her credence in h , t and t will remain unchanged. hence p(h ) = p(t ) = p(t ) = / ; so p(heads) = p(h ) = / . i agree with this reasoning. dorr then argues that there are no relevant differences between his variant case and the original case with respect to p(h ). i disagree. there is a crucial difference between beauty after a minute in the variant case and beauty after a minute in the original case. in the variant case, a certain pos- sibility has been eliminated. it could have turned out that it was heads and tuesday. not only could it have been heads and tuesday, beauty could have known it was heads and tuesday. she would have known this for certain if she had suddenly got a flood of memories from the previous day. a t u n ive rsity o f c a lifo rn ia , b e rke le y o n a u g u st , h ttp ://a n a lysis.o xfo rd jo u rn a ls.o rg d o w n lo a d e d fro m http://analysis.oxfordjournals.org darren bradley this flood of memories would have made heads more likely. the absence of this flood makes heads less likely. that is, she can conditionalize on the absence of a flood of memories and conclude that heads is less likely. while she was waiting for a possible flood of memories in that first minute, she had no new evidence about how the coin landed. if she got a flood of memories, she would increase the probability that the coin landed heads (to ). so in the absence of a flood of memories, she would have to decrease the probability that the coin fell heads. in the original case, there is no such possibility. there is no possibility that beauty will find out for certain that it fell heads. so she cannot update on the lack of such information. unlike in the variant case, beauty has no non-indexical information to conditionalize on. dorr asks why this delay of a minute, the only difference between the original sleeping beauty and the variant case should make any difference to subjective probabilities. i answer that in the variant case a hypothesis that could have been eliminated has failed to be (h ). there is no equiva- lent of this is in the original case. the variant case is uninformative. stanford university stanford, ca , usa dbradley@stanford.edu references dorr, c. . sleeping beauty: in defence of elga. analysis : – . i would like to thank branden fitelson for helpful discussion. a t u n ive rsity o f c a lifo rn ia , b e rke le y o n a u g u st , h ttp ://a n a lysis.o xfo rd jo u rn a ls.o rg d o w n lo a d e d fro m http://analysis.oxfordjournals.org communication may notices of the ams across all areas of mathematics. a list of the research publications of the math faculty during – runs to sixty-six pages and contains over one thousand entries. a major phd producer, the department in recent decades has turned out between . percent and percent of all math doctorates in the nation. the department publishes a journal, the illinois journal of mathematics, founded in by illinois mathematicians reinhold baer and joseph l. doob, along with abraham taub, george whitehead, and oscar zariski. another way to gauge the department’s in- fluence is through its extensive service to the mathematical community. two illinois math- ematicians served as ams president: doob ( – ) and arthur byron coble ( – ). robert m. fossum served as ams secretary from to and might hold the record for serving on the largest number of ams committees (the current ams secretary, carla savage, got her phd at illinois). philippe tondeur served as director of the division of mathematical sciences of the national science foundation (nsf) from until , a period in which math was named an nsf “priority area” and received double-digit increases. yet another example is paul t. bateman, a larger- than-life figure with outsize energy and enthusiasm who served as ams associate secretary and was on the board of trustees. he joined the illinois faculty in and re- mained active through his retirement in and until his death in . bateman built up the department in ways big and small, raising its research profile, hosting annual grill parties, and organizing a softball team known as the p. t. batsmen. from to he served as head and presided over a dramatic expansion of the department. in the s, as faculty hired during the bateman era began to retire, the department hired several new fac- ulty per year for several years running. not seeking to reproduce its past research strengths, the department big is beautiful: illinois wins exemplary program award allyn jackson eighty thousand credit hours. twenty-six thousand stu- dent classes. twelve hundred math majors, two hundred twenty-five graduate students, seventy tenure-stream faculty, and twenty postdocs. these numbers capture one aspect of the mathematics department at the university of illinois at urbana–champaign: it is big. the depart- ment has faced all the challenges typical in departments of its kind, including shrinking resources, pressure from other departments over math requirements, steep increases in undergraduate enrollments, and heightened expectations for teaching quality. far from tottering under the weight of these responsibilities, illinois has thrived. the department’s large size brings a wealth of expertise and creativity to bear on the chal- lenges it faces. the faculty have set in motion innovations that have increased the quality of the educa- tion it delivers at all levels, stimulating the enthusiasm of both students and faculty. long a successful depart- ment, illinois has become one that is truly outstanding. for these achievements, the mathematics department at the university of illinois has received the ams award for an exemplary program or achievement in a mathematics department. an influential department neither an ivy leaguer nor a member of the coastal elite, the university of illinois at urbana–champaign neverthe- less possesses a mathematics department that has long been prominent on the mathematical scene. the depart- ment’s large size allows it to maintain research strength allyn jackson is senior writer and deputy editor of the notices. her e-mail address is axj@ams.org. for permission to reprint this article, please contact: reprint-permission@ams.org. doi: http://dx.doi.org/ . /noti bringing the department to a new level of excellence mailto:axj@ams.org mailto:reprint-permission@ams.org http://dx.doi.org/ . /noti communication notices of the ams volume , number instead focused simply on getting outstanding mathema- ticians. many of the people hired in that period have now emerged as leaders in the department’s recent achieve- ments. they have capitalized on the longstanding tradi- tions and experience at illinois to bring the department’s functions to a new level of excellence. responding to shifting student needs like many math departments across the country, illinois has seen an increase in the number of math majors, though the increase at illinois has been particularly sharp, up from five years ago to , today. according to randy mccarthy, director of undergraduate studies, this increase is not due to more students preparing for grad- uate school or for careers in secondary school. rather, it has been fueled in large part by students who are doing “math plus,” that is, a double major in mathematics plus another subject, such as computer science, engineering, or economics. students value the addition of math for the insight it brings into the sophisticated modeling and statistical tools that are pervasive in quantitative areas. also, the financial crisis raised uncertainties about job prospects after college. students used to be able to count on good grades leading to a good job, mccarthy said. “nowadays, they are much less confident they are going to get that job, and they are looking for an edge. they feel math gives them a competitive edge.” the illinois department has excelled in responding to such shifts in the needs and expectations of its students. one innovation in this direction is the illinois geometry lab (igl). the igl was founded by jayadev athreya, who has since moved to the university of washington (where he has opened a similar lab); currently the director is jeremy tyson. the igl offers undergraduates the opportunity to work on semester-long projects under the guidance of faculty. not all of the projects are in geometry, and many focus on applications of mathematics to other subjects, but they all have a large computational component. top- ics have ranged from modeling taxi routes in new york city, to studying properties of knots with a large number of crossings, to solving problems related to lithium-ion battery design, to investigating randomness in number theory. the students learn what it’s like to work on a team and struggle with open-ended problems. this builds communication skills, as do the end-of-semester talks the students present before the entire lab. the igl has a second purpose: to showcase mathemat- ics to the general public and to k– students. the lab conducts about twenty-five public outreach activities each year, which have igl students toting the lab’s -d printer to places like farmers’ markets and schools. there are also events in which k– students visit the igl. reaching thousands of people, these events have stoked enthusiasm for mathematics among the general public—and among the igl students. “the students who get involved in igl projects are interested in doing collaborative, interactive things,” said department chair matthew ando. “they have a lot of energy, and they like to communicate about math- ematics. it’s turned out to be a very strong community for outreach.” currently about sixty undergraduates par- ticipate in igl projects. with funding from nsf and from donors, the department plans to increase this number by supporting more postdocs who can initiate igl projects. another departmental innovation began around ten years ago, when complaints came from the engineering school about calculus classes. one of the complaints was an oft-heard one: engineering students need a calculus class that specifically prepares them for engineering appli- cations. another was that many engineering students with good scores on the ap calculus bc exam did poorly when placed directly into multivariable calculus. the math de- partment collaborated with the engineering school to develop a new course, team-taught by mathematicians and engineers. together they developed prob- lem sets based on science and engineering applications, which students work on in teams in active-learning mode during discussion sections. they also strategically reorganized the syl- labus so that the course covers the traditional calculus and calculus in a single semester. and instead of easing stu- dents in with familiar material, the course starts off with taylor series. “so we disrupt their idea that they know the material really well,” ando said. “that gets their attention!” illinois geometry lab volunteers matthew romney and vanessa rivera quiñones creating materials for outreach work. the students “feel math gives them a competitive edge.” communication may notices of the ams department has begun extending the large-lecture model to other courses, such as linear algebra. the faculty remain wistful about the loss of small classes but have found that the large-lecture model brings some unexpected advan- tages. in the days of the small calculus classes, “you would just pick up your book and go teach,” ando said. “thirty students—what could go wrong?” with the large-lecture courses taught by two or three faculty, “we learned how to collaborate with each other.” when someone who has not taught the course before comes in to teach it, he or she learns the ropes from colleagues and inherits a wealth of experience. “we have a lot materials, we have videos, a bunch of worksheets, and instructions for tas on how to run the sections,” ahlgren said. “we can pass on the knowledge of how to run this operation. this process has grown organically.” ahlgren also noted that the collabo- ration has brought greater consistency to the courses. in addition to providing a model for improving its large- lecture classes, the collaboration with the engineering school has changed how the math department is perceived on campus. richard laugesen, the department’s director of graduate studies, said that twenty years ago engineering faculty members would often grumble that the mathema- ticians weren’t interested in applied topics and paid no attention to the needs of engineering students. “we don’t hear any of that now,” laugesen remarked. “they under- stand that we are engaged and we want to work with them to find solutions for their students.” the department meets needs of students in many other ways. its actuarial science program enrolls almost undergraduate majors and is growing at the graduate level to address increasing demand in risk management. the department also has a distance-learning program called netmath, founded twenty-five years ago by debra woods and the late jerry uhl, which provides opportunities for high school students and nontraditional students. most recently, netmath has offered summer courses for illinois undergraduates. “we learned a lot from developing and teaching that course,” ando continued. “and then this marvelous thing happened.” as faculty rotated through the course, they became “infected” by the active-learning model. this model had actually been used for twenty-five years in the department’s merit program for emerging scholars. based on the ideas of uri treisman, the program recruits students who have strong academic records and come from traditionally “un- derserved” populations, which include minority groups underrepresented in mathematics as well as first-generation college students. merit students attend regular lectures, but instead of traditional one-hour discussion sec- tions, they participate in two-hour “workshops” in which they collaborate on problem sets. the success of the merit students and of those in the new engineering calculus class got the department to thinking. “people realized that the active-learning model of the engineering calculus course would work in other larger courses,” recalled associate chair scott ahlgren. around this same time, climbing student enrollments and budget constraints led the department to consolidate its approx- imately calculus classes, which had around – students apiece, into large lecture classes with -student discussion sections. the sections are conducted entirely in active-learning mode, with groups of students collab- orating on problem sets as tas circulate around, giving hints and encouraging students to talk to each other. all students have a stake in participating: everyone must write up a solution set, but from each group only one set, chosen at random, will be graded. after ten years of patient work on large-lecture calcu- lus, the courses are working smoothly and efficiently. in that time, the department’s total teaching load went from , student-courses a year to , today. so the graduate students relaxing in the common room. an active-learning classroom in action. faculty became “infected” by the active-learning model. communication notices of the ams volume , number said. “the courses are a foundation to help them figure out what they want to do. but the emphasis is on getting them connected with an advisor and getting them into research.” each fall laugesen meets with every single doctoral student—all of them—to monitor their progress and help them clear obstacles they may have encountered. in the spring, each student must present a formal progress report. “it’s remarkable the effect [the timetable] has,” laugesen said. “when there is no goal or requirement or deadline, then a lot of people will drift. when they know what they have to accomplish, they tend to get it done.” through the systematic use of the timetable, the depart- ment has seen the time-to-degree decrease. one of the biggest innovations the department has made is to give students opportunities that prepare them for careers outside academia. with funding from the nsf, the department created pi (program for interdisciplinary and industrial internships at illinois), which provides training and internships for phd students. the program includes a “summer computational boot camp” in which students pick up programming skills. they are then placed in internships in companies or laboratories or in other departments on the illinois campus where mathematical thinking can make a contribution to research. the number of summer internships has grown from six in to a total of thirty-one in . the internships do not slow the progress towards the phd. “in fact, quite the reverse,” laugesen noted. “students who aim at an industry career tend to finish a little quicker because they are very mo- tivated.” “we want you to succeed” melinda lanius majored in math at wellesley college and had no idea what area she might specialize in when she joined the phd program at illinois. halfway around the world, caglar uyanik did his undergraduate work at middle east technical university in ankara, turkey, one of that nation’s premier public research universities. he wanted to do geometric group theory and decided on illinois for graduate school because of its strength in that area. these two very different students, with very different starting points, are now close to finishing their phds. both thrived in the illi- nois department. uyanik spoke of the friendliness of both the graduate students and the fac- ulty, noting that there is “more solidarity than competition” among the students. lanius said, “you can figure out what type of mathematician you want to be while at illinois, and then there is a ton of support to help you prepare for and realize that choice.” serving well the broad range of graduate students who enter the phd program is a major focus at illinois. attri- tion is low; if the department recruits twenty-five new students in the doctoral program, said laugesen, usually twenty-four are back the second year. “that’s a reason we tell students, ‘come to illinois. we are investing in you, and we want you to succeed.’” in recent years, the department has worked hard to increase diversity in its graduate student population. today the graduate student body is percent women, up from about percent a decade ago. “that’s something that we feel has really changed the tone of the phd program,” laugesen noted. the department’s association for women in mathematics (awm) chapter, founded in , runs a host of activities that are open to all students and that have deepened the sense of community in the department. through tireless recruiting at events like sacnas meetings and the field of dreams conferences, the department has also increased the number of students from minorities underrepresented in mathematics, who now account for percent of the us citizens in the phd program. the program is “very streamlined,” laugesen said. in- stead of a qualifying or comprehensive examination that students must pass early on, the program requires satis- factory grades in basic coursework in the first year and a half. one required course is math , which is essentially a seminar in which faculty members give informal talks about their areas of research to help students get oriented toward choosing an advisor. the foreign language require- ment, which was a hindrance to some students, has been eliminated. the department has developed a timetable that spells out the milestones toward the degree and when a student should reach them. by the end of the second year, students are expected to have found an advisor and have begun working on a thesis proposal. “this all helps emphasize that it is a research-focused degree,” laugesen using the illinois geometry lab’s -d printer, undergraduate student hiroshi fuii designed and printed colorful plastic models to illustrate how circles, ellipses, hyperbolas, and parabolas arise as conic sections. when stacked together the pieces of the model form a cone. the cross sections revealed by the slices range through the full set of “conic sections.” faculty member steven bradlow used the models in a course on curves that he taught at the african institute of mathematical sciences in january . the phd program is “very streamlined.” communication may notices of the ams ability, and commitment to the department. the ambassa- dors participate in outreach events and act as an advisory group for the undergraduate program. what is the secret to the department’s success? “we have a particularly healthy and mature department,” mc- carthy said. “we don’t have a lot of turf wars or people arguing among each other.” the faculty members place a strong emphasis on research but at the same time are very student oriented. many of them have received teach- ing awards (as have many graduate students serving as tas). the faculty’s shared commitment to students serves to shift discussions away from narrow self-interest and toward the question, what is best for the students? that the department is so big reinforces the shared focus on students. “we have such a critical mass, we are so large, that once you have that attitude, it tends to be self-sta- bilizing,” said mccarthy. even when faculty members go through an upheaval, it doesn’t last long because everyone remembers the pleasant steady-state environment that usually prevails. “there is a strong desire to return back to that healthy norm,” mccarthy said. as big as the illinois department is, ando believes the ams award his department has received actually reflects the achievements of an even bigger group. having served as chair for five years, he has visited many other depart- ments doing similar things. “there are great things going on in mathematics departments across the country,” he said. “i hope that this award will help draw attention to the efforts and achievements of the whole mathematics community.” photo credits photo of colorful plastic models is courtesy of laura schaposnik. all remaining photos are courtesy of the department of math- ematics at the university of illinois at urbana–champaign. laugesen and two of his colleagues, yuliy baryshnikov and lee deville, described the pi program in an article that appeared in the march issue of the notices (https://tinyurl.com/bardevlau). the article notes that currently around , mathematical sciences phds are produced every year in the united states, while each year only about , tenure-track positions are under recruitment. inevitably, many new phds seek employment outside academia, but mathematics faculty do not always have relevant experience to guide them. “there are ways in which mathematics is useful in the world that twenty or twenty-five years ago, when i was in graduate school, we just never would have imagined,” laugesen said. programs like pi provide a model that other departments can use to better prepare their graduate students for the many new opportunities that are opening up outside academia. a healthy and mature department like many math departments at state institutions, illinois operates under considerable budget pressure and uncer- tainty. but the faculty has been entrepreneurial in seeking support for the many things they do. in addition to grants for programs like pi , more than half of the faculty hold individual or small-group research grants. the depart- ment is the hub of a large research network called gear (geometric structures and representation varieties), led by steve bradlow and supported by a us$ . -million nsf grant. netmath contributes to the department in many ways, for example, by supporting teaching assistantships and fellowships for graduate students, as well as research experiences for undergraduate students. donors support a variety of programs, such as lecture series, scholarships, and named professorships. the drive and enthusiasm of the faculty rub off on the students. for example, lanius and other students created a summer math camp for high school students, now held annually on the illinois cam- pus. she has served as an officer in the department’s awm chapter, organizing social events for the entire mathematics graduate stu- dent population that help students to bond and sup- port each other during the year. the chapter also has its own colloquium series, with talks accessible to first- and second-year graduate students, and offers professional de- velopment workshops on topics like creating a website and how to give an “elevator pitch.” last fall the awm chapter officers came to ando with a list of several activities that they hoped the department would fund. “they have such initiative,” ando remarked. “we are not a wealthy depart- ment, but if somebody comes to ask for funds for such worthy activities, you turn around and find the money.” to capitalize on the enthusiasm of the undergraduate majors, the department has created “mathematics ambassadors,” a program that each year designates around twenty math majors who exemplify academic strength, leadership students, faculty, and staff gathered in front of altgeld hall, home of the illinois mathematics department. preparing students for careers outside academia https://tinyurl.com/bardevlau request unsuccessful. incapsula incident id: - measurement of beauty production in deep inelastic scattering at hera physics letters b ( ) – www.elsevier.com/locate/physletb measurement of beauty production in deep inelastic scattering at hera zeus collaboration s. chekanov, m. derrick, j.h. loizides , s. magill, s. miglioranzi , b. musgrave, j. repond, r. yoshida argonne national laboratory, argonne, il - , usa m.c.k. mattingly andrews university, berrien springs, mi - , usa n. pavel institut für physik der humboldt-universität zu berlin, berlin, germany p. antonioli, g. bari, m. basile, l. bellagamba, d. boscherini, a. bruni, g. bruni, g. cara romeo, l. cifarelli, f. cindolo, a. contin, m. corradi, s. de pasquale, p. giusti, g. iacobucci, a. margotti, a. montanari, r. nania, f. palmonari, a. pesci, l. rinaldi, g. sartorelli, a. zichichi university and infn bologna, bologna, italy g. aghuzumtsyan, d. bartsch, i. brock, s. goers, h. hartmann, e. hilger, p. irrgang, h.-p. jakob, o. kind, u. meyer, e. paul , j. rautenberg, r. renner, a. stifutkin, j. tandler , k.c. voss, m. wang physikalisches institut der universität bonn, bonn, germany d.s. bailey , n.h. brook, j.e. cole, g.p. heath, t. namsoo, s. robins, m. wing h.h. wills physics laboratory, university of bristol, bristol, united kingdom -  published by elsevier b.v. doi: . /j.physletb. . . open access under cc by license. http://www.elsevier.com/locate/physletb http://creativecommons.org/licenses/by/ . / zeus collaboration / physics letters b ( ) – m. capua, a. mastroberardino, m. schioppa, g. susinno calabria university, physics department and infn, cosenza, italy j.y. kim, i.t. lim, k.j. ma, m.y. pac chonnam national university, kwangju, south korea m. helbich, y. ning, z. ren, w.b. schmidke, f. sciulli nevis laboratories, columbia university, irvington on hudson, ny , usa j. chwastowski, a. eskreys, j. figiel, a. galas, k. olkiewicz, p. stopa, l. zawiejski institute of nuclear physics, cracow, poland l. adamczyk, t. bołd, i. grabowska-bołd , d. kisielewska, a.m. kowal, m. kowal, j. Łukasik, m. przybycień, l. suszycki, d. szuba, j. szuba faculty of physics and nuclear techniques, agh-university of science and technology, cracow, poland a. kotański , w. słomiński department of physics, jagellonian university, cracow, poland v. adler, u. behrens, i. bloch, k. borras, v. chiochia, d. dannheim , g. drews, j. fourletova, u. fricke, a. geiser, p. göttlicher , o. gutsche, t. haas, w. hain, s. hillert , c. horn, b. kahle, u. kötz, h. kowalski, g. kramberger, h. labes, d. lelas, h. lim, b. löhr, r. mankel, i.-a. melzer-pellmann, c.n. nguyen, d. notz, a.e. nuncio-quiroz, a. polini, a. raval, u. schneekloth, u. stösslein, g. wolf, c. youngman, w. zeuner deutsches elektronen-synchrotron desy, hamburg, germany s. schlenstedt desy zeuthen, zeuthen, germany g. barbagli, e. gallo, c. genta, p.g. pelfer university and infn, florence, italy a. bamberger, a. benen, f. karstens, d. dobur, n.n. vlasov fakultät für physik der universität freiburg i.br., freiburg i.br., germany zeus collaboration / physics letters b ( ) – p.j. bussey, a.t. doyle, j. ferrando, j. hamilton, s. hanlon, d.h. saxon, i.o. skillicorn department of physics and astronomy, university of glasgow, glasgow, united kingdom i. gialas department of engineering in management and finance, university of aegean, greece t. carli, t. gosau, u. holm, n. krumnack, e. lohrmann, m. milite, h. salehi, p. schleper, t. schörner-sadenius, s. stonjek , k. wichmann, k. wick, a. ziegler, ar. ziegler hamburg university, institute of experimental physics, hamburg, germany c. collins-tooth , c. foudas, r. gonçalo , k.r. long, a.d. tapper imperial college london, high energy nuclear physics group, london, united kingdom p. cloth, d. filges forschungszentrum jülich, institut für kernphysik, jülich, germany m. kataoka , k. nagano, k. tokushuku , s. yamada, y. yamazaki institute of particle and nuclear studies, kek, tsukuba, japan a.n. barakbaev, e.g. boos, n.s. pokrovskiy, b.o. zhautykov institute of physics and technology of ministry of education and science of kazakhstan, almaty, kazakhstan d. son kyungpook national university, center for high energy physics, daegu, south korea j. de favereau, k. piotrzkowski institut de physique nucléaire, université catholique de louvain, louvain-la-neuve, belgium f. barreiro, c. glasman , o. gonzález, l. labarga, j. del peso, e. tassi, j. terrón, m. zambrana departamento de física teórica, universidad autónoma de madrid, madrid, spain m. barbi, f. corriveau, s. gliga, j. lainesse, s. padhi, d.g. stairs, r. walsh department of physics, mcgill university, montréal, pq, h a t canada zeus collaboration / physics letters b ( ) – t. tsurugai meiji gakuin university, faculty of general education, yokohama, japan a. antonov, p. danilov, b.a. dolgoshein, d. gladkov, v. sosnovtsev, s. suchkov moscow engineering physics institute, moscow, russia r.k. dementiev, p.f. ermolov, i.i. katkov, l.a. khein, i.a. korzhavina, v.a. kuzmin, b.b. levchenko, o.yu. lukina, a.s. proskuryakov, l.m. shcheglova, s.a. zotkin moscow state university, institute of nuclear physics, moscow, russia i. abt, c. büttner, a. caldwell, x. liu, j. sutiak max-planck-institut für physik, münchen, germany n. coppola, g. grigorescu, s. grijpink, a. keramidas, e. koffeman, p. kooijman, e. maddox, a. pellegrino, s. schagen, h. tiecke, m. vázquez, l. wiggers, e. de wolf nikhef and university of amsterdam, amsterdam, netherlands n. brümmer, b. bylsma, l.s. durkin, t.y. ling physics department, ohio state university, columbus, oh , usa a.m. cooper-sarkar, a. cottrell, r.c.e. devenish, b. foster, g. grzelak, c. gwenlan , t. kohno, s. patel, p.b. straub, r. walczak department of physics, university of oxford, oxford, united kingdom p. bellan, a. bertolin, r. brugnera, r. carlin, f. dal corso, s. dusini, a. garfagnini, s. limentani, a. longhin, a. parenti, m. posocco, l. stanco, m. turcato dipartimento di fisica dell’ università and infn, padova, italy e.a. heaphy, f. metlica, b.y. oh, j.j. whitmore department of physics, pennsylvania state university, university park, pa , usa y. iga polytechnic university, sagamihara, japan g. d’agostini, g. marini, a. nigro dipartimento di fisica, università ‘la sapienza’ and infn, rome, italy zeus collaboration / physics letters b ( ) – c. cormack , j.c. hart, n.a. mccubbin rutherford appleton laboratory, chilton, didcot, oxon, united kingdom c. heusch university of california, santa cruz, ca , usa i.h. park department of physics, ewha womans university, seoul, south korea h. abramowicz, a. gabareen, s. kananov, a. kreisel, a. levy raymond and beverly sackler faculty of exact sciences, school of physics, tel-aviv university, tel-aviv, israel m. kuze department of physics, tokyo institute of technology, tokyo, japan t. fusayasu, s. kagawa, t. tawara, t. yamashita department of physics, university of tokyo, tokyo, japan r. hamatsu, t. hirose , m. inuzuka, h. kaji, s. kitamura , k. matsuzawa tokyo metropolitan university, department of physics, tokyo, japan m. costa, m.i. ferrero, v. monaco, r. sacchi, a. solano università di torino and infn, torino, italy m. arneodo, m. ruspa università del piemonte orientale, novara, and infn, torino, italy t. koop, j.f. martin, a. mirea department of physics, university of toronto, toronto, on, m s a canada j.m. butterworth , r. hall-wilton, t.w. jones, m.s. lightwood, m.r. sutton , c. targett-adams physics and astronomy department, university college london, london, united kingdom j. ciborowski , r. ciesielski , p. Łużniak , r.j. nowak, j.m. pawlak, j. sztuk , t. tymieniecka, a. ukleja, j. ukleja , a.f. żarnecki warsaw university, institute of experimental physics, warsaw, poland zeus collaboration / physics letters b ( ) – m. adamus, p. plucinski institute for nuclear studies, warsaw, poland y. eisenberg, d. hochman, u. karshon, m. riveline department of particle physics, weizmann institute, rehovot, israel a. everett, l.k. gladilin , d. kçira, s. lammers, l. li, d.d. reeder, m. rosin, p. ryan, a.a. savin, w.h. smith department of physics, university of wisconsin, madison, wi , usa s. dhawan department of physics, yale university, new haven, ct - , usa s. bhadra, c.d. catterall, s. fourletov, g. hartner, s. menary, m. soares, j. standage department of physics, york university, on, m j p canada received may ; accepted august available online september editor: w.-d. schlatter abstract the beauty production cross section for deep inelastic scattering events with at least one hard jet in the breit frame together with a muon has been measured, for photon virtualities q > gev , with the zeus detector at hera using integrated luminosity of pb− . the total visible cross section is σ bb̄ (ep → e jet µx) = . ± . (stat.)+ . − . (syst.) pb. the next-to- leading order qcd prediction lies about . standard deviations below the data. the differential cross sections are in general consistent with the nlo qcd predictions; however at low values of q , bjorken x, and muon transverse momentum, and high values of jet transverse energy and muon pseudorapidity, the prediction is about two standard deviations below the data.  published by elsevier b.v. open access under cc by license. e-mail address: rik.yoshida@desy.de (r. yoshida). also affiliated with university college london, uk. retired. self-employed. pparc advanced fellow. now at dongshin university, naju, south korea. partly supported by polish ministry of scientific research and information technology, grant no. p b . partly supported by polish ministry of scientific research and information technology, grant no. p b . supported by the polish state committee for scientific re- search, grant no. p b . now at columbia university, ny, usa. now at desy group feb. now at university of oxford, uk. partly supported by moscow state university, russia. now at university of oxford, uk. now at the department of physics and astronomy, university of glasgow, uk. now at royal holoway university of london, uk. also at nara women’s university, nara, japan. also at university of tokyo, japan. ramón y cajal fellow. pparc postdoctoral research fellow. mailto:rik.yoshida@desy.de http://creativecommons.org/licenses/by/ . / zeus collaboration / physics letters b ( ) – on leave of absence at the national science foundation, ar- lington, va, usa. now at queen mary college, university of london, uk. retired. present address: tokyo metropolitan university of health sci- ences, tokyo - , japan. also at university of hamburg, alexander von humboldt fel- low. pparc advanced fellow. also at Łódź university, poland. supported by the polish state committee for scientific re- search, grant no. p b . Łódź university, poland. Łódź university, poland, supported by the kbn grant no. p b . supported by the kbn grant no. p b . on leave from moscow state university, russia, partly sup- ported by the weizmann institute via the us–israel binational sci- ence foundation. supported by the natural sciences and engineering research council of canada (nserc). supported by the german federal ministry for education and research (bmbf), under contract nos. hz gua , hz gub , hz pda , hz vfa . supported in part by the minerva gesellschaft für forschung gmbh, the israel science foundation (grant no. / - . ), the us–israel binational science foundation and the benozyio center for high energy physics. supported by the german–israeli foundation and the israel science foundation. supported by the italian national institute for nuclear physics (infn). supported by the japanese ministry of education, culture, sports, science and technology (mext) and its grants for scien- tific research. supported by the korean ministry of education and korea sci- ence and engineering foundation. supported by the netherlands foundation for research on matter (fom). supported by the polish state committee for scientific re- search, grant no. /e- /spb/desy/p- /dz / - . partially supported by the german federal ministry for educa- tion and research (bmbf). supported by rf president grant no. . . for the lead- ing scientific schools and by the russian ministry of industry, sci- ence and technology through its grant for scientific research on high energy physics. supported by the spanish ministry of education and science through funds provided by cicyt. supported by the particle physics and astronomy research council, uk. supported by the us department of energy. supported by the us national science foundation. . introduction deep inelastic scattering (dis) offers a unique op- portunity to study the production mechanism of bot- tom (b) quarks via the strong interaction in a clean environment where a point-like projectile, a photon with a virtuality q , collides with a proton. due to the large centre-of-mass energy, bb̄ pairs are copi- ously produced at the electron–proton collider hera. the large b-quark mass provides a hard scale, mak- ing perturbative quantum chromodynamics (qcd) ap- plicable. however, a hard scale can also be given by the transverse jet energy and by q. the presence of two or more scales can lead to large logarithms in the calculation which can possibly spoil the conver- gence of the perturbative expansion. precise differen- tial cross-section measurements are therefore needed to test the theoretical understanding of b-quark pro- duction in strong interactions. the cross sections for b-quark production in strong interactions have been measured in proton–antiproton collisions at the spp̄s [ ] and the tevatron [ ] and, more recently, in two-photon interactions at lep [ ] and in γp interactions at hera [ , ]. some of the b- production cross sections are significantly above the qcd expectations calculated to next-to-leading order (nlo) in the strong coupling constant, αs . this letter reports the first measurement of b-quark production in dis at hera, in the reaction with at least one hard jet in the breit frame [ ] and a muon, from a b decay, in the final state: ep → ebb̄x → e + jet + µ + x. in the breit frame, defined by γ + xp = , where γ is the momentum of the exchanged photon, x is the bjorken scaling variable and p is the proton momen- tum, a space-like photon and a proton collide head-on. in this frame, any final-state particle with a high trans- verse momentum is produced by a hard qcd interac- tion. supported by the polish ministry of scientific research and in- formation technology, grant no. /e- /spub/desy/p- /dz / - . supported by the polish state committee for scientific re- search, grant no. /e- /spub-m/desy/p- /dz / - , p b . zeus collaboration / physics letters b ( ) – in this letter, a measurement of the visible cross section, σbb̄ , is presented, as well as several differen- tial cross sections. the measured cross sections are compared to monte carlo (mc) models which use leading order (lo) matrix elements, with the inclu- sion of initial- and final-state parton showers, as well as to nlo qcd calculations. all cross sections are measured in a kinematic region in which the scattered electron, the muon and the jet are well reconstructed in the zeus detector. . experimental conditions the data used in this measurement were collected during the – hera running period, where a proton beam of gev collided with a positron or electron beam of . gev, corresponding to a centre- of-mass energy of gev. the total integrated lumi- nosity was ( . ± . ) pb− . a detailed description of the zeus detector can be found elsewhere [ , ]. a brief outline of the com- ponents that are most relevant for this analysis is given below. the high-resolution uranium-scintillator calorimeter (cal) [ ] consists of three parts: the for- ward (fcal), the barrel (bcal) and the rear (rcal) calorimeters. each part is subdivided transversely into towers and longitudinally into one electromagnetic section (emc) and either one (in rcal) or two (in bcal and fcal) hadronic sections (hac). the smallest subdivision of the calorimeter is called a cell. the cal energy resolutions, as measured under test-beam conditions, are σ (e)/e = . /√e (gev) for electrons and σ (e)/e = . /√e (gev) for hadrons. charged particles are tracked in the central track- ing detector (ctd) [ ], which operates in a magnetic field of . t provided by a thin superconducting solenoid. the ctd consists of cylindrical drift- chamber layers, organised in nine superlayers cov- ering the polar-angle region ◦ < θ < ◦. the the zeus coordinate system is a right-handed cartesian sys- tem, with the z axis pointing in the proton beam direction, referred to as the “forward direction”, and the x axis pointing left towards the centre of hera. the coordinate origin is at the nominal inter- action point. transverse-momentum resolution for full-length tracks can be parameterised as σ (pt )/pt = . pt ⊕ . ⊕ . /pt , with pt in gev. the position of electrons scattered at small an- gles to the electron beam direction was measured us- ing the small-angle rear tracking detector (srtd) [ , ]. the srtd is attached to the front face of the rcal and consists of two planes of scintillator strips, arranged orthogonally. the strips are cm wide and . cm thick. the muon system consists of tracking detectors (forward, barrel and rear muon chambers: fmuon [ ], b/rmuon [ ]), which are placed inside and out- side a magnetised iron yoke surrounding the cal and cover polar angles from ◦ to ◦. the barrel and rear inner muon chambers cover polar angles from ◦ to ◦. the luminosity was measured from the rate of the bremsstrahlung process ep → eγp. the resulting small-angle energetic photons were measured by the luminosity monitor [ ], a lead-scintillator calorime- ter placed in the hera tunnel at z = − m. . event selection events were selected online via a three-level trigger system [ , ]. the trigger required a localised energy deposit in the emc consistent with that of a scattered electron. at the third level, where a full event recon- struction is available, a muon was required, defined by a track in the ctd loosely matching a track segment in the inner part of the b/rmuon chambers. the scattered electron candidate was identified from the pattern of energy deposits in the cal [ ]. the energy (ee) and polar angle (θe) of the electron are measured by combining the impact position at the calorimeter with the event vertex. the impact posi- tion is measured from the calorimeter cells associated with the electron candidate, but the ctd (θe < ◦) and srtd (θe > ◦) detectors are used to improve the measurement whenever the electron trajectory lies within the respective regions of acceptance. hereafter “electron” refers both to electrons and positron. zeus collaboration / physics letters b ( ) – the reconstruction of q was based on the mea- surement of the scattered electron energy and polar angle [ ]. the bjorken scaling variables x and y were reconstructed using the Σ -method, which allows the determination of the estimator yΣ independently of initial state photon radiation by reconstructing the in- cident electron energy [ ]. events were selected [ ] by requiring the presence of at least one muon in the final state and at least one jet in the breit frame. the final sample was selected in four steps: ( ) inclusive dis event selection • a well reconstructed scattered electron was re- quired with energy greater than gev, q > gev , yjb > . and yΣ < . , where yjb is the y variable reconstructed using the jacquet–blondel method [ ]; • for events with the scattered electron recon- structed within the srtd acceptance the impact po- sition of the electron was required to be outside a box defined by |xe| < cm and |ye| < cm. for events without srtd information, a box cut on the face of the rcal of |xe| < cm and |ye| < cm was used. this cut removed electron candidates near the inner edge of the rcal beampipe hole; • to reduce the background from collisions of real photons with protons (photo-production), where the scattered electron escapes down the rear beampipe, the variable e − pz was required to be in the range < e − pz < gev. the variable e − pz was defined as the difference of the total energy and the longitudinal component of the total momentum, cal- culated using final-state objects, reconstructed from tracks and energy deposits in the calorimeter; • the event vertex reconstructed from tracks was required to lie within cm of the nominal interaction point along the beam axis. ( ) muon finding muons were identified by requiring a track segment in both the inner and outer parts of the bmuon or rmuon chambers. the reconstructed muons were matched in space and momentum with a track found in the ctd, with a χ probability greater than %. this cut rejected the background from muons coming from k± and π ± decays and from particles produced in hadronic showers in the cal that may be misiden- tified as muons. in addition, cuts on the muon momen- tum, pµ, the muon transverse momentum, p µ t and the muon pseudorapidity, ηµ, were applied: • − . < ηµ < . and pµ t > gev correspond- ing to the bmuon region; • − . < ηµ < − . and pµ > gev corre- sponding to the rmuon region. the reconstruction efficiency of the muon chambers was calculated separately for bmuon and rmuon using an independent data sample of di-muon events produced in photon–proton collisions [ ]. this data sample consisted of elastic and quasi-elastic bethe– heitler events (γ γ → µ+µ−) and j /ψ production and it was selected from events triggered by the in- ner muon chambers. two tracks, reconstructed in the ctd, with transverse momentum greater than gev and associated with energy deposits in the cal con- sistent with a minimum-ionising particle were re- quired. one of the ctd tracks was required to point to the muon chamber that triggered the event, and the other was used to measure the muon efficiency, de- fined as the ratio of the number of tracks satisfying the muon matching requirement to the total number of tracks. the measured muon-reconstruction efficien- cies are between % and %, depending on the region of the muon chambers and on the muon trans- verse momentum. ( ) jet finding hadronic final-state objects were boosted to the breit frame and clustered into jets using the kt cluster algo- rithm (ktclus) [ ] in its longitudinally invariant in- clusive mode [ ]. the four-momenta of the hadronic final-state objects were calculated from the measured energies and angles, assuming the objects to be mass- less. the pt recombination scheme was used. recon- structed muons were included in the clustering pro- cedure. events were required to have at least one jet with transverse energy measured in the breit frame, ebreit t ,jet above gev and within the detector accep- tance, − < ηlabjet < . , where ηlabjet is the jet pseudo- rapidity in the laboratory frame. ( ) muon-jet association the muons in the sample were associated with the jet containing the corresponding hadronic final-state ob- ject using the ktclus information. the associated jet was not necessarily the jet satisfying the jet require- ments above. to ensure that the associated jet was well reconstructed, it was required to have ebreit t ,jet > gev. after these selection cuts, events remained. zeus collaboration / physics letters b ( ) – . monte carlo simulation and nlo qcd calculations to correct the results for detector effects and to ex- tract the fraction of events from b decays, two mc simulations were used: rapgap . / as default and cascade . / for systematic checks. the pre- dictions of the mc simulations were also compared to the final results. the program rapgap . / [ ] is an event generator based on leading-order (lo) matrix ele- ments, with higher-order qcd radiation simulated in the leading-logarithmic approximation using initial- and final-state parton showers based on the dglap equations [ ]. to estimate the background, sam- ples with light and charm quarks in the final state were produced. the process in which a bb̄ pair is produced in photon–gluon fusion was used to sim- ulate the signal. the charm and b-quark masses were set to . gev and gev, respectively. the cteq l [ ] parameterisation of the proton parton densities was used. heavy-quark hadronisation was modelled by the bowler fragmentation function [ ]. the rest of the hadronisation was simulated using the lund string model [ ] as implemented in jet- set . [ ]. the rapgap mc includes the lo elec- troweak corrections calculated using heracles . . [ ]. the cascade . / mc [ ] uses the o(αs ) matrix elements, where the incoming partons can be off-shell. the parton evolution is based on the ccfm equations [ ], which are derived from the principles of kt factorisation and colour coherence. the mass of the b quark was set to . gev. the nlo qcd predictions were evaluated us- ing the hvqdis program [ , ], which includes only point-like photon contributions. the fragmen- tation of a b quark into a b hadron was modelled by the kartvelishvili function [ ]. the parameter α was set to . , as obtained by an analysis [ ] of e+e− data [ ]. the semi-leptonic decay of b hadrons into muons was modelled using a parame- terisation of the muon momentum spectrum extracted from jetset, which is in good agreement with mea- surements made at b factories [ ]. this spectrum corresponds to a mixture of direct (b → µ) and indi- rect (b → c → µ) b-hadron decays. jets were recon- structed by running the inclusive kt algorithm, using the pt recombination scheme, on the four-momentum of the two or three partons generated by the pro- gram. the b-quark mass was set to mb = . gev and the renormalisation and factorisation scales to µ = √ p t ,b + m b , where pt ,b is the mean transverse momentum of the b and b̄ quarks. the cteq f pro- ton parton densities [ ] were used. the sum of the branching ratios of direct and indirect decays of b hadrons into muons was fixed to the jetset . value of . . the nlo qcd predictions were multiplied by hadronisation corrections to compare them to the mea- sured cross sections. the hadronisation corrections are defined as the ratio of the cross sections obtained by applying the jet finder to the four-momenta of all hadrons, assumed to be massless, and that from apply- ing it to the four-momenta of all partons. they were evaluated using the rapgap program; they lower the nlo qcd prediction by typically %. the uncertainty of the nlo prediction was esti- mated by varying the factorisation and renormalisation scales, µ, by a factor of and the b-quark mass, mb between . and . gev and adding the respective contributions in quadrature. additional uncertainties due to different scale choices and to different fragmen- tation functions are within the quoted uncertainties. more details of the nlo qcd calculation and of the determination of its uncertainties can be found else- where [ , , ]. . extraction of the beauty fraction a significant background to the process under study is due to muons from in-flight decays of pi- ons and kaons. such decay muons are mostly char- acterised by low momenta and, therefore, partly re- jected by the cuts pµ > gev and p µ t > gev. in addition, the signal reconstructed in the muon cham- bers can be due to kaons or pions passing through the cal. muons can also originate from the semi- leptonic decay of charmed hadrons. these decays produce events topologically similar to those under study. due to the large b-quark mass, muons from semi- leptonic b decays usually have high values of the transverse momentum, prel t , with respect to the axis of the closest jet. for muons from charm decays and zeus collaboration / physics letters b ( ) – fig. . (a) prel t distribution measured for unidentified tracks in an inclusive dis sample compared with the rap gap mc simulation (see text). data (dots) and the rap gap mc (solid line) distributions after the final event selection for: (b) the measured prel t distribution; (c) muon momentum; (d) muon pseudorapidity; (e) transverse energy in the breit frame; and (f) pseudorapidity in the laboratory frame of the associated jet. the solid line represents all mc contributions while the hatched histograms show the contribution from b quarks according to the percentage given by the fit (see section ). the error bars are statistical only. in events induced by light quarks, the prel t values are low. therefore, the fraction of events from b decays in the data sample can be extracted on a statistical ba- sis by fitting the relative contributions of the simulated bottom, charm and light-quark decays to the measured prel t distribution. zeus collaboration / physics letters b ( ) – the extraction of the fraction of b-quark decays relies on the correct simulation of the shape of the prel t distribution for all processes. the simulation was checked with the data. for this purpose, an inclusive dis data sample with at least one hard jet in the breit frame was selected, without requiring a muon in the fi- nal state. for tracks passing the same selection criteria as required for the muon, the prel t distribution was cal- culated. fig. (a) shows the comparison of the shape of the measured prel t distribution with the simulated light- and charm-quark contribution. the shape is rea- sonably well described. fig. (b) shows the measured prel t distribution for muon candidates compared to the mc simulation. the mc simulation contains the background processes from light and charm quarks and the contribution from b quarks. the distributions are peaked at low prel t val- ues, where the decays of hadrons containing charm and light quarks dominate. at higher prel t values, the measured distribution falls less steeply than that ex- pected for light-quark and charm contributions alone. to determine the b-quark fraction in the data, the con- tributions from light-plus-charm flavours and beauty in the simulation were allowed to vary, and the best fit was extracted using a binned maximum-likelihood method. the measured fraction of events from b de- cays, fb , is ( . ± . )%, where the error is statisti- cal. the mixture with the fitted fractions describes the data well. fig. (c)–(f) shows the comparison between the data and the mc simulation with respect to the mo- mentum and the pseudorapidity of the muon, as well as the associated jet transverse energy in the breit frame and the pseudorapidity of the associated jet measured in the laboratory frame. the mc simulation, with the different contributions weighted according to the frac- tions found using the fit procedure described above, reproduces the muon and jet kinematics well. . systematic uncertainties the systematic uncertainties on the measured cross sections were determined by changing the selection cuts or the analysis procedure in turn and repeating the extraction of the cross sections. the numbers given below refer to the total visible cross section, σ bb̄ . for the differential distributions the systematic uncertain- table single differential b-quark cross sections as functions of q , the bjorken-x variable, the muon transverse momentum, p µ t , the muon pseudorapidity, ηµ, and the transverse energy of the leading jet in the breit frame, ebreit t ,jet . the statistical and systematic uncertainties are shown separately q range (gev ) dσ/dq (pb/gev ) stat syst , . ± . + . − . , . ± . + . − . , . ± . + . − . log (x) range da/dx (pb) stat syst − . , − . . ± . + . − . − . , − . . ± . + . − . − . , − . . ± . + . − . p µ t range dσ/dp µ t stat syst (gev) (pb/gev) , . ± . + . − . , . ± . + . − . , . ± . + . − . ηµ range dσ/dηµ (pb) stat syst − . , − . . ± . + . − . − . , . . ± . + . − . . , . . ± . + . − . ebreit t ,jet range dσ/de breit t ,jet stat syst (gev) (pb/gev) , . ± . + . − . , . ± . + . − . , . ± . + . − . ties were determined bin-by-bin and are included in the figures and in table . the following systematic studies were carried out: • selection cuts and srtd alignment: variation of the selection cuts on data and monte carlo by the de- tector resolution on respective variables (including the electron energy, e − pz , ebreitt ,jet , ηlabjet and srtd box cut). this led to a systematic deviation of + . % and − . % with respect to the nominal value, where the biggest uncertainties were introduced by the widened ηlabjet cut and the increased e breit t ,jet cut. the relative alignment between the rcal and the srtd detec- zeus collaboration / physics letters b ( ) – tor is known to a precision of ± mm [ ]. the re- lated systematic uncertainty was conservatively esti- mated by shifting the reconstructed srtd hit position by ± mm in both coordinates and was + . % and − . %, respectively; • energy scale: the effect of the uncertainty in the absolute cal energy scale of ± % for hadrons and of ± % for electrons was + . % and − . %; • extraction of b decays: the uncertainties related to the signal extraction were estimated by doubling and halving the charm contribution. this leads to a systematic uncertainty of + . % and − . %, respec- tively. the uncertainty obtained by reweighting the light-plus-charm quark prel t distribution with the one extracted from the data as described in section is within this uncertainty; • muon reconstruction efficiency: the effect of the uncertainty on the muon reconstruction efficiency for the barrel and rear regions of the muon detectors was + . % and − . %; • model dependence of acceptance corrections: to evaluate the systematic uncertainties on the detector corrections, the results obtained with rapgap were compared with other mc models: cascade; rap- gap with the colour dipole model [ ]; and rap- gap with the peterson fragmentation function [ ]. two different values of the � parameter of the pe- terson fragmentation function were used, namely � = . and . as recently determined in e+e− collisions by the sld and opal collaborations, re- spectively [ ]. the corresponding systematic uncer- tainty was defined as the maximal deviation with re- spect to the reference sample and was + . %. these systematic uncertainties were added in quadra- ture separately for the positive and negative variations to determine the overall systematic uncertainty. these estimates were also made in each bin in which the differential cross sections were measured. the uncer- tainty associated with the luminosity measurement for the – data-taking periods used in this analy- sis was ± . %. this introduces an overall normal- isation uncertainty on each measured cross section, which is correlated between all data points. this is added in quadrature to the other systematic uncertain- ties on the total visible cross section, but is not in- cluded in the figures or tables of the differential cross section measurements. . results the total visible cross section, σ bb̄ , was determined in the kinematic range q > gev , . < y < . with at least one hadron-level jet in the breit frame with ebreit t ,jet > gev and − < ηlabjet < . and with a muon fulfilling the following conditions: − . < ηµ < . and p µ t > gev or − . < ηµ < − . and pµ > gev. the jets were defined by applying the kt algorithm to stable hadrons; weakly decaying b (and d) hadrons are considered unstable. the muons coming from direct and indirect b decays are matched to any jet in the event. the measured cross section is σbb̄(ep → ebb̄x → e jet µx) = . ± . (stat.)+ . − . (syst.) pb. this measurement has been corrected for electroweak radiative effects using heracles. the nlo qcd prediction with hadronisation corrections is . + . − . pb which is about . standard deviations lower than the measured total cross section. the cascade mc pro- gram gives σbb̄ = pb and rapgap gives σbb̄ = pb. the differential cross sections were calculated in the same restricted kinematic range as the total cross section by repeating the fit of the prel t distribution and evaluating the electroweak radiative corrections in each bin. the results are summarised in table . fig. (a) and (b) shows the differential cross sec- tions as functions of q and x, respectively, compared to the nlo qcd calculation. the nlo qcd pre- dictions generally agree with the data; in the lowest q and lowest x bins, the data are about two stan- dard deviations higher. fig. (c) and (d) shows the same differential cross sections compared with the rapgap and cascade mc simulations. cascade agrees with the data except for the lowest q and low- est x bin. rapgap is well below the data in all bins, but it reproduces the shapes of the data distributions. fig. (a) and (b) shows the differential cross sec- tions as functions of the transverse momentum, p µ t , and pseudorapidity, ηµ, of the muon, compared to the nlo qcd calculation. they generally agree with the data; in the lowest p µ t bin and the high ηµ bin, the nlo qcd prediction is about two standard deviations below the data. fig. (c) and (d) shows the same differ- ential distribution compared with cascade and rap- gap. cascade describes the measured cross sections zeus collaboration / physics letters b ( ) – fig. . differential b-quark cross section as a function of (a) q and (b) bjorken x for events with at least one jet reconstructed in the breit frame and a muon, compared to the nlo qcd calculations. the error bars on the data points correspond to the statistical uncertainty (inner error bars) and to the statistical and systematic uncertainties added in quadrature (outer error bars). the solid line shows the nlo qcd calculations with the hadronisation corrections and the dashed line the same calculation without the hadronisation corrections. the shaded bands show the uncertainty of the nlo qcd prediction due to the variation of the renormalisation and factorisation scale, µ, and the b-quark mass, mb . differential b-quark cross sections as a function of (c) q and (d) bjorken x, compared with the lo qcd mc programs cas cade (solid line) and rap gap (dashed line). well except for the lowest p µ t bin, while rapgap lies below the data. fig. (a) shows the differential cross section as a function of ebreit t ,jet of the leading jet compared to the nlo qcd calculation. the nlo qcd prediction agrees with the data reasonably well, though it is sys- tematically below. for the highest ebreit t ,jet bin the differ- ence is about two standard deviations. fig. (b) shows the same differential distribution compared with cas- cade and rapgap. for all ebreit t ,jet values, cascade reproduces the measured cross section reasonably well while rapgap lies below the data. zeus collaboration / physics letters b ( ) – fig. . differential b-quark cross section as a function of (a) the muon transverse momentum p µ t and (b) muon pseudorapidity ηµ in the laboratory frame, compared to the nlo qcd calculations. other details are as described in the caption to fig. . differential b-quark cross section as a function of (c) p µ t and (d) ηµ, compared with lo qcd mc programs cas cade (solid line) and rap gap (dashed line). . conclusions the production of b quarks in the deep inelastic scattering process ep → eµ jet x has been measured with the zeus detector at hera. the nlo qcd prediction for the visible cross section lies about . standard deviations below the measured value. single differential cross sections as functions of the photon virtuality, q , the bjorken scaling variable, x, the transverse momentum and pseudorapidity of the muon as well as the transverse energy of the leading jet in the breit frame have been measured. the cas- cade mc program, implementing the ccfm qcd evolution equations, gives a good description of the measured cross sections. it is, however, below the data for low values of the transverse momenta, low q and low values of x. rapgap is well below the data for all measured cross sections. the differential cross sec- zeus collaboration / physics letters b ( ) – fig. . (a) differential b-quark cross section as a function of the transverse energy of the jet in the breit frame ebreit t ,jet . the data (dots) are compared to the nlo qcd calculations (a). other details are as described in the caption to fig. . (b) differential b-quark cross sections as a function of ebreit t ,jet compared with lo qcd mc programs cas cade (solid line) and rap gap (dashed line). tions are in general consistent with the nlo qcd predictions; however at low values of q , bjorken x, and muon transverse momentum, and high values of jet transverse energy and muon pseudorapidity, the prediction is about two standard deviations below the data. in summary, b-quark production in dis has been measured for the first time and has been shown to be in general consistent with nlo qcd calculations. acknowledgements we thank the desy directorate for their strong support and encouragement. the special efforts of the hera group are gratefully acknowledged. we are grateful for the support of the desy computing and network services. the design, construction and installation of the zeus detector have been made possible by the ingenuity and effort of many people who are not listed as authors. we thank b.w. har- ris and j. smith for providing the nlo code. we also thank h. jung and m. cacciari for useful discus- sions. references [ ] ua collaboration, c. albajar, et al., phys. lett. b ( ) ; ua collaboration, c. albajar, et al., phys. lett. b ( ) , erratum. 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[ ] t. sjöstrand, comput. phys. commun. ( ) . [ ] a. kwiatkowski, h. spiesberger, h.-j. möhring, comput. phys. commun. ( ) . [ ] h. jung, g.p. salam, eur. phys. j. c ( ) , the version . / of the program is used; h. jung, comput. phys. commun. ( ) . [ ] m. ciafaloni, nucl. phys. b ( ) ; s. catani, f. fiorani, g. marchesini, phys. lett. b ( ) . [ ] b.w. harris, j. smith, phys. rev. d ( ) . [ ] b.w. harris, j. smith, nucl. phys. b ( ) ; b.w. harris, j. smith, phys. lett. b ( ) . [ ] v.g. kartvelishvili, a.k. likhoded, v.a. petrov, phys. lett. b ( ) . [ ] m. cacciari, p. nason, phys. rev. lett. ( ) . [ ] aleph collaboration, a. heister, et al., phys. lett. b ( ) . [ ] belle collaboration, k. abe, et al., phys. lett. b ( ) ; babar collaboration, b. aubert, et al., phys. rev. d ( ) . [ ] t. carli, v. chiochia, k. klimek, jhep ( ) . [ ] f. goebel, phd thesis, university of hamburg ( ), desy- thesis- - . 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[ ] sld collaboration, f. abe, et al., phys. rev. d ( ) ; opal collaboration, g. abbiendi, et al., eur. phys. j. c ( ) . http://www-zeus.desy.de/bluebook/bluebook.html measurement of beauty production in deep inelastic scattering at hera introduction experimental conditions event selection monte carlo simulation and nlo qcd calculations extraction of the beauty fraction systematic uncertainties results conclusions acknowledgements references appl. sci. , , ; doi: . /app www.mdpi.com/journal/applsci article perspective morphometric criteria for facial beauty and proportion assessment luca ulrich ,*, jean-luc dugelay , enrico vezzetti , sandro moos and federica marcolin digep, politecnico di torino, torino, italy; enrico.vezzetti@polito.it (e.v.); sandro.moos@polito.it (s.m.); federica.marcolin@polito.it (f.m.) digital security, campus sophiatech, eurecom, cs biot sophia antipolis cedex, france; jean- luc.dugelay@eurecom.fr * correspondence: luca.ulrich@polito.it; tel.: + - - - received: october ; accepted: december ; published: december abstract: common sense usually considers the assessment of female human attractiveness to be subjective. nevertheless, in the past decades, several studies and experiments showed that an objective component in beauty assessment exists and can be strictly related, even if it does not match, with proportions of features. proportions can be studied through analysis of the face, which relies on landmarks, i.e., specific points on the facial surface, which are shared by everyone, and measurements between them. in this work, several measures have been gathered from studies in the literature considering datasets of beautiful women to build a set of measures that can be defined as suggestive of female attractiveness. the resulting set consists of measures applied to a public dataset, the bosphorus database, whose faces have been both analyzed by the developed methodology based on the expanded set of measures and judged by human observers. results show that the set of chosen measures is significant in terms of attractiveness evaluation, confirming the key role of proportions in beauty assessment; furthermore, the sorting of identified measures has been performed to identify the most significant canons involved in the evaluation. keywords: face analysis; face proportions; attractiveness; d landmarks; features extraction . introduction the beauty and proportion of the human face have always been an object of interest through the years, as evidenced by greek sculptures, ancient egyptian paintings, and even in prehistory [ ]. some studies have also been carried on during the renaissance period by well-known artists, such as leonardo da vinci [ ] and michelangelo buonarroti [ ], but it is from the th century that systematic studies focused on objective assessments began. several studies of facial aesthetics have focused on specific aspects, such as the role of the divine proportion legacy of ancient greeks, [ – ], the average intended as an instrument to delete imperfections [ , ], the average plus exaggerated sex-specific traits to discriminate between beauty and attractiveness [ ], and the relative importance of some traits of the face [ ]. the presence of a strong objective component in beauty assessment has been clearly shown by several experiments, including iliffe’s [ ], udry’s [ ] and cunningham’s [ ]. cultural influence on beauty assessment is very strong, as testified by different canons that have been adopted through the years to assess female beauty. during the paleolithic period, statuettes of “venus”, representing women, were sculpted in such a way that they looked full-figured to symbolize fecundation, fertility and regeneration [ ]. ancient egyptians considered a large forehead and well-defined mandibles attractive [ ]. on the contrary, greeks preferred an oval facial shape for both men and women, and a forehead as small as possible to highlight the hair [ ]. in the middle appl. sci. , , of age, there is evidence of a preference for larger foreheads and absence of wrinkles, even if the sign at the time was not considered ugly, as testified by contemporary positive reflections on grey hair [ ]. cultural differences can also be found within the same period. in recent times, debates over femininity depicted by the media have been widely discussed [ ], suggesting that beauty relies on the eye of the beholder, but there are several experiments, including the above-mentioned, suggesting that beauty is assessed through quantitative tips, even if hidden, especially regarding the face. as criteria for beauty assessment began to be presented to the scientific community [ ], several studies focusing on analyzing databases of attractive and common individuals have been conducted, from the identification of facial esthetic canons in italian children in the deciduous and early mixed dentition [ ] to the soft-tissue analysis of adolescent boys’ and girls’ faces [ ]. there have also been studies on people of non-caucasian ethnicity, such as southern chinese faces [ ]; nevertheless, women have been the most widely studied subset of the human population. several works show comparisons between normal and attractive women. the normal term has been used in the literature to identify common, non-selected women, whereas attractive is typically used to identify good-looking women, typically chosen among actresses [ ] or beauty contest participants [ , ]. results appearing in these studies confirm the presence of objective elements defining beauty related to the concept of proportions between different parts of the face in terms of euclidean distances and angular measurements. in those works, as in the current research, attractiveness is understood as the harmony between facial forms rather than the sexual impact on the observer. objective beauty would be the expression that fits best for defining the kind of attractiveness evaluated by human judges in beauty contests, which is the same faced by the current work. nonetheless, it would be superficial to claim that beauty can be totally assessed from a quantitative point of view, thus it has been chosen to preserve the attractiveness acceptation intended in previously cited works in this field. the medical field is the most interesting discipline in studying this topic, since some branches of surgery must intervene directly on face by modifying the shape, both for merely aesthetic and pathological reasons [ ]; therefore, it is not surprising that the study of two orthodontists, peck and peck [ ], was one of the first works aimed at discovering and gathering facial features. over the last two decades, there has been an incremental increase of d imaging, such as mri, ct [ ] and stereophotogrammetry [ – ], and d modelling [ ]. in this context, geometrical descriptors [ ] and landmarks [ ] proved to be highly effective tools, since they allow the observer to gather common traits that everybody shares to perform facial analysis. this evolution has provided the possibility of analyzing point clouds reproducing patients’ faces for diagnosis [ , ] and surgical intervention planning, for which handbooks are nowadays widely used [ ], but it has also allowed us to build virtual faces from scratch [ ]. before the advent of d tools, face operation planning evaluations relied on two-dimensional images acquired on sagittal, coronal, and axial planes [ , ]. the idea for this research project was conceived to make a socially-responsible contribution to this field. in past months, a partnership with the maxillofacial department of molinette hospital in turin allowed the authors of this paper to review all findings linked to facial reconstruction due to pathological problems. very general guidelines for tissue reconstruction after a surgical intervention exist, but they are not a valuable auxilium, and physicians need more accurate indications. obviously, the reconstruction target is to obtain a good-looking face, and the present work has been directed on that need. nonetheless, surgeons’ experience is irreplaceable. facial proportions and beauty are strongly interconnected concepts. however, while proportions can be evaluated mainly from a d point of view, beauty assessment is more complex; indeed, facial expression [ ] and all elements perceivable with color information cannot be ignored [ ]. also, d information has been used to manipulate textures [ ], figuring out that not only attractiveness, but also other individual characteristics, such as age and health, are differently perceived because of colors cues [ , ]. skin is the most studied element in terms of color and texture, because of the wide percentage of facial surface which recovers [ – ], and it has been proved that factors such as makeup and photo quality have a strong influence on attractiveness [ ]. appl. sci. , , of some databases of human faces were built to be analyzed and to provide new suggestions for further feature extraction and proportion studies, but also to validate results already obtained. two available databases are the d facial norm ( dfn) [ ] and the bosphorus sets, employed in the development of the current research work, which provides faces belonging to more than one hundred subjects in various poses, expressions and different types of occlusions [ ]. the present work gathers facial measures that have been identified in previous studies as representative of female face attractiveness with the purpose of classifying female faces. after that, the bosphorus, meaning a database of normal women, has been used to test whether the final set of canons is suitable and sufficient for women’s attractiveness evaluation. the novelties in this work are the development of a methodology capable of putting together data identified by different sources in the literature in order to obtain an expanded set of measures comprehensive of all the works published up-to-now, and to provide a ranking of the measures included in the expanded set to understand which are the most significant in attractiveness assessment. results confirm that the evaluation of selected measures corresponds closely to human assessments, providing the opportunity to quantitatively analyze women’s beauty; moreover, a ranking showing the influence of measures in women’s facial beauty and proportion assessment has been drawn up. the importance of ratios between measures and the higher relevance of the vertical measures compared to the horizontal have been highlighted. . materials and methods face analysis is the discipline that studies human faces based on the identification of landmarks, specific points common to everyone that can be identified on the face. landmarks can be recognized on the hard tissue through palpation or on the soft tissue through observation, even if some of the landmarks positioned on the soft tissue depend on landmarks positioned on the hard tissue. in order to evaluate women’s attractiveness from a quantitative point of view, an expanded set of measures, relying on landmark positions, has been defined. the most difficult step in evaluating female beauty is to identify a ground truth that allows us to make considerations on measures of women’s faces. significant experiments proving the presence of a strong objective component have been conducted; iliffe’s [ ] and udry’s [ ] works showed that almost identical classifications are obtained when people are asked to judge and rank the beauty in specific photo galleries, as well as cunningham’s [ ], which stated that beauty cannot be defined as a quality resting only in the eye of the beholder. in the past decades, several works aiming at establishing which human facial traits influence an observer’s assessment of beauty have been conducted. works considered as the most incisive in this field, thus taken into greater account in the present work, have been carried out by farkas et al. [ ], ferrario et al. [ ], sarver et al. [ ], sforza et al. [ ] and galantucci et al. [ ]. each of those works has been carried out via live-positioning landmarks on female subjects before the acquisition of the point cloud required to compute measures. manual allocation directly on subjects has been chosen in order to achieve the best accuracy possible. acquisitions have been made using an rgb-d camera, namely cameras which allow to acquire both color and depth images. subjects were actresses, participants to beauty contests, and common women; the latter have been chosen to validate the results. going deeper into detail, the purpose of computing and comparing facial measures has been to highlight the correlation among some measures in the set of attractive women and the differences with the same measures in the set of normal women. whenever the difference has been evaluated as significant, the measure related to that difference has been classified as influential for women’s facial beauty and proportion assessment. as it can be seen in table , the vast majority of measures belonging to the expanded set show a statistically significant difference between galantucci’s attractive and normal women datasets. table . since values of single measures related to the attractive set of women are available only for the galantucci et al. database [ ], a t-test has been performed between measures in this dataset and those ones in bosphorus. the significance level has been fixed to %. this means that differences between measures are significant if the p-value is lower than . . appl. sci. , , of measure p-value n-pg . n-sn . ch_r-ch_l . ex_r-ex_l . sn-pg . t_r-t_l . ls-(prn-pg) . li-(prn-pg) . ls-li . en_r-en_l . ac_r-ac_l . n-gn . sn-gn . ls-sto . li-sto . n-sn-pg . sl-n-sn . prn-sn-ls . n-prn-pg . ex_l-n-ex_r . mf(pg-n-ls) . en_l-n-en_r . (t_r-t_l)/(n-pg) . (n-sn)/(n-pg) . (sn-pg)/(n-pg) . (t_r-n)/(t_r-sn) . (sn-pg)/(n-sn) . (sn-gn)/(n-gn) . (sto-gn)/(sn- gn) . all the information found by those studies were gathered here to obtain an expanded set of measures able to evaluate women’s attractiveness; then, the bosphorus database was used to validate the expanded set of measures, comparing it with qualitative evaluations issued by human observers. there are subjects in bosphorus database, but only the selected women have been analyzed in this work. the landmark framework considered in this work is reported in table and shown in figure . table . the landmark framework. the third column reports a description for each landmark [ ]. landmark abbreviatio n description alar curvature point ac point located at the facial insertion of each alar base. cheilion ch point located at each labial commissure. endocanthion en soft tissue point located at the inner commissure of each eye fissure. exocanthion ex soft tissue point located at the outer commissure of each eye fissure. gonion (or menton) gn (or me) most inferior midpoint on the soft tissue contour of the chin. labiale inferius li midpoint of the vermilion line of the lower lip. appl. sci. , , of labiale superius ls midpoint of the vermilion line of the lower lip. nasion n midpoint on the soft tissue contour of the base of the nasal root at the level of the frontonasal suture. pogonion pg most anterior midpoint of the chin. pronasale prn most anterior midpoint of the nasal tip. stomion sto midpoint of the horizontal labial fissure. sublabiale sl most posterior point on the labiomental soft tissue contour that defines the border between the lower lip and the chin. subnasale sn midpoint on the nasolabial soft tissue contour between the columella crest and the upper lip. tragion t point located at the upper margin of each tragus. figure . figure showing landmarks studied in the current work. landmarks (zy_l), (zy_r), (midpoint of tragi), (g), (al_l) and (al_r) have been discarded due to a lack of available measures involving them. suffixes _l and _r state that the landmark considered is respectively the left or the right one. all the measures considered in this analysis have been acquired employing the above- mentioned landmarks and can be subdivided into three categories: linear, angular, and ratios. linear measures described in table and shown in figure are euclidean distances between two landmarks or between a landmark and another specific point. more specifically, one of those specific points is the point on the e-line that minimizes the distance with labiale superius (or labiale inferius), where the e-line is the line passing through the pronasal and the pogonion. table . euclidean linear distances. the third column reports the work from which the measure has been taken. measure description references n-pg facial line ferrario et al. [ ], galantucci et al. [ ] n-sn anterior upper facial ° third height ferrario et al. [ ], galantucci et al. [ ] appl. sci. , , of ch_r-ch_l oral length farkas et al. [ ], sarver et al. [ ], galantucci et al. [ ] ex_r-ex_l upper facial width ferrario et al. [ ], sforza et al. [ ], galantucci et al. [ ] sn-pg anterior lower facial height galantucci et al. [ ] t_r-t_l middle facial width galantucci et al. [ ] ls-(prn- pg) upper lip to e-line distance galantucci et al. [ ] li-(prn- pg) lower lip to e-line distance sforza et al. [ ], galantucci et al. [ ] ls-li vermilion height galantucci et al. [ ] en_r-en_l intercantal distance farkas et al. [ ], sarver et al. [ ] ac_r-ac_l width nose base farkas et al. [ ], sarver et al. [ ] n-gn facial height farkas et al. [ ], sarver et al. [ ] sn-gn lower third facial height farkas et al. [ ], sarver et al. [ ] ls-sto upper vermilion farkas et al. [ ], sarver et al. [ ] li-sto lower vermilion farkas et al. [ ], sarver et al. [ ] figure . euclidean distances. angular measures described in table and shown in figure are angles subtended by a vertex identified by three landmarks or, exceptionally for the interlabial distance, by two lines lying on the same plane and identified by four landmarks, two for each line. appl. sci. , , of table . the angular measures. the third column reports the work from which the measure has been taken. measure description references n-sn-pg facial convexity excluding the nose ferrario et al. [ ], galantucci et al. [ ] sl-n-sn maxillary prominence ferrario et al. [ ], galantucci et al [ ] prn-sn-ls nasolabial farkas et al. [ ], sarver et al. [ ], galantucci et al. [ ] n-prn-pg nasion – pronasal - pogonion galantucci et al. [ ] ex_l-n- ex_r left exocanthion – nasion - right exocanthion sforza et al. [ ] pg-n-ls maxillo-facial angle (mf) galantucci et al [ ] en_l-n- en_r left endocanthion-nasion-right endocanthion ferrario et al. [ ] figure . angular measures. ratios between linear distances (table ) allow us to perform quantitative evaluations of proportions. the face analysis moves the focus from the local to the global point of view, since not only the absolute value of one single measure is considered, but rather the overall effect of two measures. intuitively, ratios are the quantitative way to represent the big picture. table . ratios of euclidean distances. the third column reports the work from which the measure has been taken. appl. sci. , , of measure description references (t_r-t_l)/(n-pg) middle facial width to facial height galantucci et. al [ ] (n-sn)/(n-pg) nasion - subnasale/nasion - pogonion ferrario et al. [ ], galantucci et. al [ ] (sn-pg)/(n-pg) subnasale - pogonion/nasion - pogonion ferrario et al. [ ], galantucci et. al [ ] (t_r-n)/(t_r-sn) right tragi-nasion/right tragi- subnasale galantucci et. al [ ] (sn-pg)/(n-sn) lower to upper facial height galantucci et. al [ ] (sn-gn)/(n-gn) lower third/facial height farkas et al. [ ], sarver et al. [ ] (sto-gn)/(sn- gn) mandibula/lower third farkas et al. [ ], sarver et al. [ ] as a result of the literature review, twenty-nine measures have been identified. the present work employs data from the bosphorus database, namely women’s pictures, d models, and relative landmark coordinates. because all the studies previously cited were carried out by research groups with different expertise, slightly different sets of landmarks have been adopted. a landmarking expert identified some missing landmarks on d pictures and on d models on the bosphorus database in order to complete the landmark framework. nonetheless, some landmarks had to be discarded because they relied on the hard tissue, and the only way to identify them was through palpation. thus, it has not been possible to include some measures into the expanded set. an example is the zygion (zy), which is the most lateral point on the soft tissue contour of each zygomatic arch. the works of galantucci et al. [ ], farkas et al. [ ], sarver et al. [ ], ferrario et al. [ ] and sforza et al. [ ] provided mean value and standard deviation for every measure. some measures are common to different sources, even if the related mean value and standard deviation are slightly different depending on the study. the small sample size of attractive sets of women is due to the complexity of finding available databases providing data, i.e., not only images, but also d models and information like landmarks position. indeed, one of the purposes of the present study is to merge the information coming from these sources (figure ) and build an overall measuring methodology. figure . definition of the expanded set of measures. a score, the result of the sum of penalties, has been computed for each woman present in the bosphorus database. for each measure, if the value of the considered woman was within the range appl. sci. , , of mean value ± standard deviation, no penalty has been added. for the sake of clarity, it has to be highlighted that the mean value taken into consideration is the mean value of the measures belonging to the attractive sets of women and not the mean value referred to a generic non-selected group of women (normal women). conversely, if the value was out of range, a penalty has been added, and the amount of penalty ( ) has been computed as the ratio between the distance of the measure from the mean value normalized with the mean value. 𝑝𝑒𝑛𝑎𝑙𝑡𝑦 = 𝑤𝑒𝑖𝑔ℎ𝑡 ∗ | 𝑐𝑢𝑟𝑟𝑒𝑛𝑡 𝑤𝑜𝑚𝑎𝑛 𝑠 𝑚𝑒𝑎𝑠𝑢𝑟𝑒 – 𝑚𝑒𝑎𝑛 𝑣𝑎𝑙𝑢𝑒 |𝑚𝑒𝑎𝑛 𝑣𝑎𝑙𝑢𝑒 ( ) in the case of more than one mean value, since there is more than one source in the literature that refers to the same measure, the computed penalty value has been then multiplied for weight ( ). 𝑤𝑒𝑖𝑔ℎ𝑡 = # 𝑤𝑜𝑚𝑒𝑛 𝑖𝑛 𝑐𝑢𝑟𝑟𝑒𝑛𝑡 𝑠𝑡𝑢𝑑𝑦#𝑤𝑜𝑚𝑒𝑛 𝑖𝑛 𝑎𝑙𝑙 𝑡ℎ𝑒 𝑠𝑡𝑢𝑑𝑖𝑒𝑠 𝑟𝑒𝑓𝑒𝑟𝑟𝑖𝑛𝑔 𝑡𝑜 𝑡ℎ𝑒 𝑠𝑎𝑚𝑒 𝑚𝑒𝑎𝑠𝑢𝑟𝑒 ( ) this weight has been introduced to consider the different degree of confidence assigned to different studies found in the literature. remembering that in those studies canons have been extracted from sets of attractive women, it was considered essential to evaluate more robustly the analysis using a greater number of subjects. thus, the weights have been computed as the ratio between the number of women involved in a single study and the sum of all the women involved in all the studies related to the same measure. for instance, consider a hypothetical measure identified by two studies, a and b, which involves x and y women, respectively. the weight related to the study a will be x/(x+y), while the weight related to the study b will be y/(x+y). after all the scores were obtained, a cluster analysis was performed through the usage of k-means methodology, subdividing the datasets into five classes. the purpose of this step was to identify which women were closer to the well-proportioned standard face in terms of compliance with the measures in the expanded set; in other words, considering the descending order adopted, faces belonging to class are closer to the well-proportioned standard face than the faces belonging to class . the number of classes has been chosen to have a correspondence with the likert scale. indeed, in parallel, a qualitative evaluation of the women present in bosphorus has been made by a focus group using precisely the likert scale. a comparison between the results obtained using the developed methodology and the qualitative evaluation performed by human observers has been performed (figure ). finally, the results of the developed methodology in terms of cluster subdivision have been analyzed to rank the influence of each measure of the expanded set in women’s facial beauty and proportion assessment. appl. sci. , , of figure . the methodology used to compare quantitative and qualitative evaluation. . results the measures selected from literature and included in the expanded set are reported in table . for every measure, it is possible to have more than one mean value and one standard deviation due to the possibility of retrieving the same measure from different sources in literature; the last column reports the reference number of the considered source. table . list of the final set of measures. reference [ ] analyzes two different beauty contests (miss italia and miss italia ) that provide slightly different values. the year markers of “ ” and “ ” have been added in some references to distinguish between those two contests. measure mean value standard deviation reference n-pg . . [ ] . . [ ] n-sn . . [ ] . . [ ] ch_r-ch_l . . [ ] . [ ] ex_r-ex_l . . [ ] . . [ ] . . [ ]— . . [ ]— sn-pg . . [ ] t_r-t_l . . [ ] ls-(prn-pg) . . [ ] li-(prn-pg) . . [ ] . . [ ]— appl. sci. , , of . . [ ]— ls-li . . [ ] en_r-en_l . [ , ] ac_r-ac_l . [ , ] n-gn . [ , ] sn-gn . [ , ] ls-sto . . [ , ] li-sto . . [ , ] n-sn-pg . . [ ] . . [ ] sl-n-sn . . [ ] . . [ ] prn-sn-ls . . [ ] n-prn-pg . . [ ] ex_l-n-ex_r . . [ ]— . . [ ]— pg-n-ls . . [ ] en_l-n-en_r . . [ ] (t_r-t_l)/(n-pg) . . [ ] (n-sn)/(n-pg) . . [ ] . . [ ] (sn-pg)/(n-pg) . . [ ] . . [ ] (t_r-n)/(t_r-sn) . . [ ] (sn-pg)/(n-sn) . . [ ] (sn-gn)/(n-gn) . . [ , ] (sto-gn)/(sn- gn) . . [ , ] after the expanded set definition, each of the forty-four women in bosphorus database were measured, and the scores were computed summing all the penalties. scores were subdivided into five clusters so that it is easy to identify women’s faces closer to the well-proportioned standard face, remembering that clusters are arranged in descending order; namely, faces belonging to cluster are the closest to the well-proportioned standard face, and conversely, faces belonging to cluster are the furthest. hereafter, a focus group composed by people, men and women aged between and years old met up to evaluate bosphorus women attractiveness. for every face, a discussion between focus group members led to a final score. in other words, the whole group provided a single score for each face analyzed. the aim of that was to compare the developed methodology with human judgment. the results showed that the cluster label and the likert’s scale label are the same; namely, the difference between those two values equals for / women (very high correspondence); the difference is for / women (high correspondence); the difference is for / women (moderate correspondence); the difference is for / women (low correspondence); and the difference is for / women (very low correspondence). very high correspondence means that the result of the method matches the focus group’s outcome (a woman with very high correspondence label has been judged in the same way both by the method and by the focus group). all those results are reported in table . appl. sci. , , of table . scores, cluster labels, qualitative evaluation labels and correspondence between quantitative and qualitative evaluations for each woman. subjec t score cluster label qualitative evaluation label correspondenc e . high . moderate . high . very high . very high . high . very high . high . moderate . very high . high . high . very high . very high . moderate . high . low . high . high . high . very high . very high . very high . moderate . high . very high . high . moderate . low . very high . high . high . very high . moderate . moderate . very high . very low . moderate . high . low . moderate . high . very high . very high finally, results obtained through cluster analysis were more deeply analyzed. the purpose of this step was to rank the measures to understand which are the most important in women’s facial beauty and proportion assessment. in particular, the focus was moved on cluster and cluster , appl. sci. , , of which contain attractive and very attractive women, respectively. knowing the cardinality of each cluster, that is if clusters and are taken together, values out of range have been computed for each measure; a measure must be considered influential if the smallest possible number of women has that measure out of range. for instance, referring to table , it is possible to notice that the euclidean distance ls-sto is the most influential measure, because only two women ( %) belonging to cluster and cluster are out of range; conversely, ch_r-ch_l is one of the least influential measures because only out of women are within range. table . the measures rankings. the cardinality of each cluster is reported in the header of the table. the first column lists the measures, and the second column reports the number of women belonging to cluster or that are out of range. for the sake of completeness, in the other columns, the number of women belonging to each cluster has been reported. measures cluster + (# ) cluster (# ) cluster (# ) cluster (# ) cluster (# ) cluster (# ) ls-sto ( %) ( %) ( %) ( %) ( %) ( %) (sn-pg)/(n- sn) ( %) ( %) ( %) ( %) ( %) ( %) n-sn ( %) ( %) ( %) ( %) ( %) ( %) sn-gn ( %) ( %) ( %) ( %) ( %) ( %) (t_r-n)/(t_r- sn) ( %) ( %) ( %) ( %) ( %) ( %) ex_r-ex_l ( %) ( %) ( %) ( %) ( %) ( %) sl-n-sn ( %) ( %) ( %) ( %) ( %) ( %) (t_r-t_l)/(n- pg) ( %) ( %) ( %) ( %) ( %) ( %) n-gn ( %) ( %) ( %) ( %) ( %) ( %) li-sto ( %) ( %) ( %) ( %) ( %) ( %) n-prn-pg ( %) ( %) ( %) ( %) ( %) ( %) (sn-gn)/(n- gn) ( %) ( %) ( %) ( %) ( %) ( %) en_l-n-en_r ( %) ( %) ( %) ( %) ( %) ( %) (sn-pg)/(n- pg) ( %) ( %) ( %) ( %) ( %) ( %) n-pg ( %) ( %) ( %) ( %) ( %) ( %) pg-n-ls ( %) ( %) ( %) ( %) ( %) ( %) (n-sn)/(n-pg) ( %) ( %) ( %) ( %) ( %) ( %) ls-li ( %) ( %) ( %) ( %) ( %) ( %) en_r-en_l ( %) ( %) ( %) ( %) ( %) ( %) n-sn-pg ( %) ( %) ( %) ( %) ( %) ( %) ac_r-ac_l ( %) ( %) ( %) ( %) ( %) ( %) (sto-gn)/(sn- gn) ( %) ( %) ( %) ( %) ( %) ( %) sn-pg ( %) ( %) ( %) ( %) ( %) ( %) ex_l-n-ex_r ( %) ( %) ( %) ( %) ( %) ( %) prn-sn-ls ( %) ( %) ( %) ( %) ( %) ( %) ch_r-ch_l ( %) ( %) ( %) ( %) ( %) ( %) li-(prn-pg) ( %) ( %) ( %) ( %) ( %) ( %) ls-(prn-pg) ( %) ( %) ( %) ( %) ( %) ( %) t_r-t_l ( %) ( %) ( %) ( %) ( %) ( %) . discussion appl. sci. , , of results provided by literature analysis have led to the first outcome of this research, namely the expanded set of measures, each of which is characterized by a mean value and standard deviation. in the literature, a measure is considered relevant for women’s facial attractiveness if a statistically significant number of attractive women possess similar values of the same measure and, conversely, that measure assumes different values in subjects belonging to the normal woman set. the critical point is to define a ground truth, i.e., a set of measures distinctive for attractive women. all the studies carried out in this field agree upon considering attractive those women’s faces that are commonly positively evaluated in terms of facial beauty and proportion, and thus famous actresses or beauty contest participants, especially those that move on to the final stage of national competitions. the present work has focused on gathering measures validated in past studies, building the expanded set of measures defined on facial landmarks and analyzing a public database of normal women, the bosphorus. unfortunately, some of the landmarks used in the literature were not present in the set of data of the bosphorus database. for this reason, an expert has manually added those missing landmarks lying on soft tissue, but some of the hard tissue landmarks have not been considered due to the impossibility of identifying them without live palpation. consequently, a limited set of measures that could have been included in the expanded set has been discarded. in order to analyze the bosphorus, a methodology able to integrate information provided by different sources was required. thus, the algorithm based on the penalty mechanism has been developed, and the results have been clustered to provide the possibility of classifying faces into different levels. the cluster numbering is from – , that means it ranges from the most compliance with the well-proportioned standard face to the least. the cluster numbering is chosen this way so that the opportunity of comparing quantitative outcome and qualitative assessment is guaranteed. likert’s -level scale has allowed us to analyze the correspondence between the developed methodology and people’s assessments. obtained results displayed in figure show the levels of correspondence in women’s evaluation from very high to very low, namely from a -level difference to a -level difference between quantitative and qualitative evaluation. the / means slightly more than %, obtained the summing of high and very high correspondence, justifying the theories mentioned in the introduction stating the presence of objective elements that are unconsciously but incontrovertibly considered in evaluating women’s attractiveness. figure . between quantitative and qualitative evaluation. cluster analysis has led this study to discover part of those elements in terms of proportions between significant measures, ranking them from the most to the least influential. some interesting observations have arisen from the ranking analysis. firstly, vertical measures are typically more meaningful than the horizontal: some examples of influential vertical measures are the thickness of the upper lip (ls-sto), the height of the central part of the face (n-sn), and the height of the lower part of the face (sn-gn). going deeper into the detail, the lower part of the face in attractive women resulted as higher than the central part, coherently with the fact that if they have identical values, faces appear rounded, a characteristic not considered attractive. the upper lip was more meaningful than lower appl. sci. , , of lip, but this does not mean it should be greater; rather, it means that it is more ordinary to have a full lower lip, while to have also a full upper lip is more uncommon, thus it is a peculiar feature of attractiveness. the angle between the two exterior corners of the eyes and the nasion, i.e., the point which separates the upper third of the face and the middle third of the face, (ex_l-n-ex_r), and the mouth width (ch_r-ch_l) at the end of the table are some examples of less meaningful horizontal measures. this does not retract the importance of mouth width in women’s faces assessment; simply, a not-so-relevant difference in mouth width between attractive and normal women has been shown by the analysis. secondly, beauty turned out to be strictly connected to proportions; out of ratios present in the expanded set of measures are on the top half of the ranking, confirming that women’s beauty and well-proportioned faces are also given by relationships between measures, thus they involve a holistic process. another indication is the relatively poor importance of the facial width absolute value, t_r-t_l, compared with the ratio between facial width and facial height, (t_r-t_l)/(n- pg), ranked in the top most influential measures. in total, % of high and very high correspondence between quantitative and qualitative evaluation is a not neglectable result, but the % non-similarity of the results needs to be investigated in future research. a larger set of attractive and normal women would allow us to enlarge the expanded set of measures, as well as the opportunity of live-acquiring all the needed landmarks, which would allow us to have uniform data in term of colors, poses, and expressions that could be more properly evaluated by humans. moreover, texture analysis in terms of eye color and skin imperfections could further thin that percentage of non-correspondence and bridge the gap between perceived beauty and facial proportions. . conclusions the present study has been carried on considering experimental evidence proving that beauty assessment is not only subjective, but also relies on objective elements. several previous studies have identified relevant measures to assess women’s facial beauty and proportion, comparing sets of attractive and normal women by measuring euclidean distances, and angular and ratio values; measures have been computed relying on landmarks live-identified on subject faces. all these works have considered different sets of measures to find differences in the normal and attractive populations. the importance of the attractive women dataset size is evidenced by the development of the methodology, which is penalty-based. that methodology has been developed to consider data provided by different sets of attractive women, in order to consider a larger number of measures. future work should focus exactly on that aspect. in the literature there is a lack of attractive women datasets, and establishing a larger database will allow us to deepen the analysis related to measures peculiar of attractiveness. the current work has defined an expanded set of measures gathering all information presented in the literature and a methodology to merge the results and to classify faces. for each woman, the methodology provides a score, computed as a sum of penalties, and each penalty is given when a woman’s measure is not in the range identified by mean value and standard deviation. that procedure has been then used on the set of normal women of the bosphorus public database, and after a cluster analysis, it has been possible to classify women’s faces considering their distance from the well-proportioned standard face, i.e., the expanded set of measures. after that, a deeper investigation on results provided by the cluster analysis has permitted us to rank the measures from the most to the least influential, to understand which the most considered measures in women’s’ beauty assessment is. vertical euclidean distances were shown to be very impactful, as well as ratio measures; indeed, the direct comparison between measures resulted in being even more significant than the single measure value, as shown by the facial width. upper lip thickness proved to be the most meaningful measure in the mouth area. the present work could make a significant contribution to female beauty and proportion assessment and proposes some research hints for future works on female attractiveness, but also for appl. sci. , , of other studies that have been discouraged by the misconception of considering beauty something merely, or mainly, subjective. author contributions: conceptualization, j.-l.d. and f.m.; methodology, l.u. and f.m.; software, l.u. and s.m.; validation, l.u.; formal analysis, l.u., j.-l.d. and f.m.; investigation, l.u.; resources, j.-l.d. and e.v.; data curation, l.u. and s.m.; writing—original draft preparation, l.u.; writing—review and editing, j.-l.d., e.v., s.m. and f.m.; visualization, l.u.; supervision, j.-l.d. and f.m.; project administration, j.-l.d. and e.v.; funding acquisition, j.-l.d. and e.v. all authors have read and agreed to the published version of the manuscript. funding: this research received no external funding. conflicts of interest: the authors declare no conflict of interest. references . nelson, s.m. diversity of the upper paleolithic venus figurines and archeological mythology. archeol. pap. am. anthropol. assoc. , , – . . naini, f.b.; cobourne, m.t.; mcdonald, f.; donaldson, a.n.a. the 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anthropometric and image repository for the clinical and research community. cleft pala. craniofac. j. , , e –e . . savran, a.; alyüz, n.; dibeklioǧlu, h.; Çeliktutan, o.; gökberk, b.; sankur, b.; akarun, l. bosphorus database for d face analysis. lect. notes comput. sci. , , – . . farkas, l.g.; schendel, s.a. anthropometry of the head and face. am. j. orthod. dentofac. orthop. , , – . . swennen, g.r.j.; schutyser, f.; hausamen, j.-e. three-dimensional cephalometry a color atlas and manual; springer: berlin/heidelberg, germany, ; isbn . © by the authors. licensee mdpi, basel, switzerland. this article is an open access article distributed under the terms and conditions of the creative commons attribution (cc by) license (http://creativecommons.org/licenses/by/ . /). microsoft word - jebo when are appearances deceiving.docx munich personal repec archive when are appearances deceiving? the nature of the beauty premium deryugina, tatyana august online at https://mpra.ub.uni-muenchen.de/ / mpra paper no. , posted feb : utc when are appearances deceiving? the nature of the beauty premium first draft: december current draft: august abstract: we design a laboratory experiment to illuminate the channels through which relatively more attractive individuals receive higher wages. specifically, we are able to distinguish taste-based discrimination from rational statistical discrimination and biased beliefs. using three realistic worker tasks to increase the external validity of our results, we find that the “beauty premium” is highly task-specific: while relatively more attractive workers receive higher wage bids in a bargaining task, there is no such premium in either an analytical task or a data entry task. the premium in the bargaining task is driven by biased beliefs about worker performance. we find that there is substantial learning after worker- specific performance information is revealed, highlighting the importance of accounting for longer-run interactions in studies of discrimination. jel classification: c , j , j key words: beauty premium, discrimination, economic experiments, labor markets . introduction labor market discrimination based on characteristics such as gender, age, race, and national origin is illegal. appearance-based discrimination, while not currently unlawful in most labor markets, has been the subject of several lawsuits in recent years. in the academic literature, several studies have found that people who are relatively more attractive are paid more, even when the situation does not appear to warrant it (hamermesh and biddle, ; biddle and hamermesh, ). this phenomenon has been termed the “beauty premium.” it appears to be pervasive: versions of the beauty premium have been found in settings that include credit markets (ravina, ), professional sports (berri et al., ), and even elections (berggren et al., ). moreover, there is extensive evidence that beauty is correlated with career choices, including the choice to become a criminal (hamermesh and biddle, ; biddle and hamermesh, ; mocan and tekin, ; von bose, ; deryugina and shurchkov, ). one potential explanation for the beauty premium is that appearance may in fact be positively correlated with skills that are important for job performance but are not easily observed and thus cannot be controlled for in an empirical study, such as the ability to be persuasive. another is that employers may overestimate the skills of relatively attractive people simply because they’re attractive. finally, employers may have unbiased beliefs about performance but prefer hiring more attractive people (“taste-based discrimination”). because most studies are observational rather than experimental, the existing evidence does not allow for these three channels to be credibly separated. we perform a computer-based laboratory experiment that allows us to distinguish these three causes from one another. we estimate the extent to which employers correctly predict the relationship between appearance and task performance, thus determining what share of the beauty premium, as measured by the wage bids, is statistical discrimination. then, by appropriately controlling for performance predictions, we are able to estimate the portion of the beauty premium that is not driven by performance expectations. the direct estimation of this taste-based component of the beauty premium also adds to previous work in which researchers were able to impute some types of taste-based discrimination only from the way in which employer beliefs are elicited. finally, because we observe workers’ actual performance, we also estimate the correlation between performance and worker appearance. together with the relationship between employer performance predictions and worker appearance, this allows us to identify any biased beliefs about the skills of comparatively attractive people. another innovation in our study meant to capture the diversity of real-world labor markets is that we estimate the extent to which the beauty premium is context-specific. we do this by randomly assigning one of three tasks to workers: a data entry task, an analytical task, or a bargaining task in which workers see pictures of their bargaining opponents. the rest of the experimental procedure remains identical across the tasks. to our knowledge, our study is the first to credibly test whether the beauty premium varies with the types of skills involved in completing a task and, if so, to determine why. because the tasks we choose are also more realistic than previously studied tasks, the variation we observe is likely to be similar to the variation in the beauty premium outside of the laboratory, therefore increasing the external validity of our results. see for example yanowitz v. l’oreal usa, inc. ( ) and brice v. resch and krueger int’l, inc. (corbett, ). see mobius and rosenblat ( ) for more experimental evidence on the beauty premium in the labor market, andreoni and petrie ( ) in public goods games, and wilson and eckel ( ) in trust games. our study is also the first to investigate how the signal value of appearance regarding a worker’s ability changes with information. it is possible that attractiveness is used as a proxy for ability at the “recruiting” stage, modeled in our experimental setting with the first round. however, it might become increasingly irrelevant as employers observe actual worker performance. to test for the existence of this type of learning, we reveal workers’ first round performance to all employers. we then repeat the prediction, bidding, and task performance stages, allowing employers to update their bids and expectations. we then estimate what portion of the beauty premium disappears once performance measures for each worker are available. we find a significant beauty premium in bargaining but not in the other two tasks (data analysis or data entry). in particular, a one-standard-deviation increase in worker attractiveness is associated with a per cent increase in the employer’s wage offer when the workers engage in a bargaining task, even after including extensive controls. by dividing attractiveness ratings into quintiles, we show that the most attractive subjects (those in the top quintile of beauty) benefit most significantly relative to the least attractive subjects. our conclusion that the beauty premium is highly context-specific is consistent with results reported in the non-experimental literature, which finds substantial beauty-based sorting into different occupations (hamermesh and biddle, ; biddle and hamermesh, ; mocan and tekin, ; von bose, ; deryugina and shurchkov, ). the beauty premium is completely explained by statistical discrimination: employers believe that more attractive workers will perform better in bargaining, where workers can see one another’s picture, but not in data entry or data analysis. this belief turns out to be incorrect: there is no significant relationship between the attractiveness rating and performance in any of the tasks, including bargaining. we find that the beauty premium completely vanishes in the second round of bidding, which suggests that employers learn quickly that performance is uncorrelated with attractiveness. past performance is also a significant determinant of wages in the second round, largely because it affects employer beliefs about worker performance. both these facts suggest that there is substantial updating by employers and that biased beliefs correct themselves quickly when objective information about performance is available. the intersection of gender and the beauty premium has been a topic of several non-labor market studies (solnick and schweitzer, ; rosenblat, ). we build upon this literature to find no systematic evidence that female or male workers benefit disproportionally from attractiveness. comparatively attractive males are expected to perform significantly better in bargaining, but do not receive larger wage bids than comparatively attractive females or less attractive males. moreover, this expectation turns out to be incorrect. our general approach shows that having measures of both (a) expectations about a worker’s performance and (b) the willingness to hire the worker (by giving her a relatively higher wage offer) are helpful for separating different kinds of discrimination. this idea can be applied in other settings and to other types of discrimination. for example, asking car dealers how much money they expect to make on a particular sale and observing their actual bargaining behavior can help determine whether offers made to women and minorities are driven by statistical or taste-based discrimination, something an earlier study on the subject was not able to determine conclusively (ayres and siegelman, ). although other methods for distinguishing taste- based from statistical discrimination have been used, direct elicitation of beliefs may be preferable, as it relies on fewer assumptions. because of the experimental nature of our work, addressing its external validity is important. according to the theory of discrimination (becker, ), taste-based discrimination is predicted to arise in real-world settings when employers expect to derive direct utility from future face-to- face interactions with relatively more attractive workers. such face-to-face interactions are absent in our experiment, making it difficult to claim that our findings about the absence of taste- based discrimination generalize to the typical office setting. however, the importance of settings where appearance is observable only through a photograph is growing with the rise of online labor markets, such as odesk (pallais, ), and online credit markets, such as prosper (ravina, ; duarte et al., ). moreover, with the increasing number of “telecommuting” workers, the old paradigm of “face time” is changing. in addition, hiring in some cases is done by temp agencies or human resources departments, which are functionally removed from daily interactions with the hired workers. our findings about taste-based discrimination are most directly relevant to such settings. the remainder of the paper is organized as follows. in section , we present an overview of our experimental procedures and descriptive statistics. section outlines the framework that allows us to differentiate biased beliefs about performance, statistical discrimination, and taste- based discrimination. section reports and discusses the results, and section concludes. . overview of the experiment . . the stylized labor market the experiment was conducted at the decision science laboratory at harvard university. subjects were undergraduate and graduate students from harvard and other boston-area universities. each session included four employers and four workers. sessions differed according to the task workers had to perform, which was randomly assigned for each session (see section iib below). the first four subjects to arrive at the laboratory and sign the consent form (our “employers”) were immediately taken from the waiting room, photographed, and seated at their stations. the next four subjects to arrive at the laboratory and sign a consent form (our “workers”) were photographed and seated afterwards. in order to avoid further face-to-face interactions between the two groups, employers and workers were seated at stations separated by a wall divider. all subjects started by having their photograph taken and answering survey questions about several characteristics that are relevant to the labor market (student status, major, and gpa as well as levels of typing, analytical, and communication skills) before being told whether they would be employers or workers. after receiving the experimental instructions, which included detailed information about the task workers would perform, employers were granted access to a evidence consistent with statistical and taste-based discrimination has been found by castillo et al. ( ) in a field study on gender differences in bargaining outcomes over taxi fares in peru. their study differs from ours insofar as it takes place in a non- labor-market setting in which beliefs are not elicited directly, but rather are inferred from observed initial price quotes. for example, the online marketplace, odesk, consists of workers all over the world who complete approximately , hours of work per week remotely (pallais, ). in the us, telecommuting increased % from to , and million u.s employees holds a job that is compatible at least part-time telework (global workplace analytics, ). most subjects arrived in the laboratory within ten minutes of one another, which ensures almost random role assignment. by assigning the role of employer to the first four subjects and removing them from the waiting room, we minimized the likelihood of face-to-face interactions between employers and workers that may have otherwise occurred during the initial waiting period. website that displayed worker photographs and the corresponding “résumés” based on each worker’s survey answers. in sessions, photos were shown on the front webpage with links to résumé information underneath each photo. in sessions, this order was reversed. the remainder of the experiment, programmed using the standard ztree software package (fischbacher, ), consisted of two procedurally identical rounds. each round started with a prediction stage during which employers submitted estimates for the expected performance of each worker in the subsequent task (eij), where i indexes employers and j indexes workers, and workers submitted estimates for their own expected performance (ej). this information was kept secret from all other subjects. the wages of both employers and workers were partly determined by the accuracy of their predictions, ensuring that subjects had incentives to guess correctly. next, employers submitted wage offers to “hire” workers. the total amount offered to four workers could not exceed a predetermined maximum number of points. we employed a second- price sealed-bid auction to allocate workers to employers: the employer with the highest wage offer for a particular worker “hired” that person and had to pay the worker the second highest wage (wj) offered to that worker. each employer could be matched with between zero and four workers, depending on the wage offers. a worker could be left unmatched if all four employers offered a zero wage to that worker, although this did not happen in practice. the wage amount (if any) was not revealed to the worker until after the task completion stage. the identity of the employer was never revealed to the worker. employers had full knowledge about the tasks workers were to perform prior to making performance predictions and wage bids. the task completion stage began after employer–worker matching was established. the task was randomly chosen prior to the start of the session to be a bargaining task, a data entry task, or a data analysis task (see detailed task descriptions below). table shows the number of sessions for each task type and the corresponding number of subjects who participated in a given session. [table about here] each round ended with an information screen. employers learned about the performance of every worker and their own payoffs for the round. workers learned about their own performance and payoffs for the round, including any wage payment. the following equations represent the total within-round payoffs. employer i’s payoff: π , , | , | worker j’s payoff: in earlier sessions, this amount equaled the employer’s endowment of points, while in the subsequent sessions this amount was raised to points with the endowment remaining at points. the increase was meant to allow employers to base their bids on their estimates of expected worker performance rather than on the mechanical constraint imposed by the bid maximum. the bid maximum does not affect the results; see the online appendix for details. if employers expect more attractive workers to be more likely to reciprocate a higher wage with higher effort, then, by withholding the wage offer information until after the worker completes the task, we are shutting down the potential “gift- exchange” mechanism behind the beauty premium. first, introducing this additional channel would greatly complicate our already complex design. furthermore, the gift-exchange channel is unlikely to drive the beauty premium, as previous work has found that more attractive individuals do not exhibit greater levels of reciprocity relative to their less attractive counterparts (see wilson and eckel ( ) in trust games, for example). π | | where ∈ , is the set of employers, ∈ , is the set of workers, and ∈ , , is the set of tasks; is the piece rate of points for t = data analysis and point for the other tasks; is the weight on the deviation of the performance estimate from actual output and equals for t = data analysis and otherwise; , is an indicator function that takes on the value of if worker j was hired by employer i, and otherwise. the last term in both equations represents a “misprediction penalty” that we include in order to incentivize truth-telling in accordance with other studies (mobius and rosenblat, ). at the end of the session, all subjects filled out a post-experiment questionnaire that asked for detailed demographic information. mean earnings in the experiment (including the show-up fee) equaled $ . with a standard deviation of $ . . sessions lasted approximately one hour. experiment instructions and questionnaire contents are available in the online appendix. . . the tasks we deliberately focus on tasks with which employers are more likely to be familiar and thus in which appearance-based differences in expectations are more likely to be correct. the abovementioned laboratory study on the beauty premium (mobius and rosenblat, ) focuses on a task type with which employers are unlikely to have prior experience and finds a substantial beauty premium despite the absence of beauty-based differences in performance. because of the lack of familiarity with the task, however, it is not clear whether it is reasonable for employers to expect appearance-based performance differences. for example, it is possible that employers are extrapolating their beliefs from other situations in which more attractive people do have a performance advantage. having workers perform realistic tasks increases our confidence in determining whether any beauty-based differences in performance predictions or wage bids are due to rational performance expectations, biased beliefs, or tastes. ex-ante, employers may have differing expectations about the relationship between attractiveness and performance in each of the three tasks, either because of a true correlation between the two or because of biased beliefs. for example, elementary school children presented with photos of individuals (all scientists) “showed a decided tendency to identify the smiling pictures as not being scientists” (bottomley et al., ). in a “draw a scientist” experiment, children typically draw an unattractive white male wearing a white lab coat and glasses (chambers, ). in a recent study, deryugina and shurchkov ( ) find that comparatively attractive female undergraduates perform worse than their less attractive counterparts on blindly graded quantitative reasoning tests and sats and are less likely to choose a science major or become scientists. thus, in the more difficult analytical task, we may find comparatively attractive individuals receiving lower wage offers because of the common stereotype that people who are good at such tasks are less attractive. incentivized belief elicitation may distort worker incentives during the task completion stage, leading to a “hedging bias”. on the other hand, monetary incentives increase truth-telling and reduce the “noise” in the beliefs data (gachter and renner, ). we prioritize the latter issue, given the recent finding that the former may not be a serious concern in belief elicitation experiments (blanco et al, ). in addition, to minimize concerns about hedging bias, we chose a relatively small mt and a generous exchange rate from points to money to ensure a salient reward for any additional effort exerted once the expected predicted performance level has been attained. on the other hand, researchers have found that attractive subjects get higher offers and therefore outperform their less attractive counterparts in simple bargaining games even without face-to-face interactions, such as the ultimatum game (solnick and schweitzer, ). thus, employers in our experiment may expect more attractive workers to perform better in our bargaining task, and therefore incorporate these expectations in their wage offers. finally, in the simple data entry task, we do not expect to see beauty-based performance or wage offer differences unless attractiveness happens to be correlated with another previously unidentified skill. . . . data entry in the data entry task, workers had six minutes to enter numerical data that they read off a sheet of paper into an excel spreadsheet. the goal was to enter as much data as possible. the data consisted of various economic statistics for regions in russia. the spreadsheets had been opened on the workers’ computers prior to the start of the experiment with the column and row headings prepared in advance, so that subjects had only to enter numerical values into the correct cells. the data had to be entered exactly as it appeared to receive credit. workers were credited with one point per correctly entered item. there was no penalty for an incorrectly entered item. . . . data analysis in the data analysis task, workers answered as many mathematical questions as possible, up to a maximum of questions. questions were based on data that were similar to those used in the data entry task. workers had six minutes for the first questions and six minutes for the second questions. because some questions required basic mathematical calculations, workers could use calculators that had been placed on their desks in advance. workers were credited with five points per correctly answered question, and there was no penalty for answering questions incorrectly. in our analysis, we likewise convert performance measures into points, multiplying the number of answers by five points. . . . bargaining in the bargaining task, workers were randomly assigned as buyers or sellers of a “widget” and participated in three -second periods of a standard double-auction. including the time it took workers to read the information screen, which was not part of the -second limit, the bargaining task lasted about six minutes, on average. workers were randomly re-matched and roles were randomly assigned with every new bargaining period. each worker saw a photo of his or her bargaining partner on a computer screen. every time a transaction was made, the seller’s profit equaled the difference between the price and the seller’s true cost of the “widget,” and the buyer’s profit equaled the difference between the buyer’s true value and the price of the “widget.” profits were calculated in tokens and then converted into points at the rate of token = point. if the time ran out before a transaction was made, both the buyer and the seller earned tokens in that bargaining period. each token was equivalent to one point for the purposes of calculating the total payoff for the round. buyers’ values and sellers’ costs were determined randomly from two uniform distributions. in some cases, the buyer’s value was below the importantly, employers were made fully aware that workers could see the photo of their bargaining partner, but that no face-to- face interactions among workers would take place at any point. seller’s cost, making profitable agreements impossible. to avoid the possibility of negative profits, sellers could not agree to an offer that was lower than their cost and buyers could not agree to an offer that was higher than their value. . . the rating procedures the rating portion of the experiment was conducted at the university of illinois, urbana- champaign (uiuc). subjects were undergraduate and graduate students from uiuc. during each session, – subjects (raters) were instructed to view and evaluate photos on a scale from (homely) to (strikingly handsome or beautiful). each rater was asked to look through four sets of photos, which appeared in random order within each photo set. due to the large number of photos, each rater evaluated only a subset of photos. the individual rating variable used in subsequent analysis is demeaned by the rater’s average across the photos that appeared in the same photo set; in other words, rater by photo-set fixed effects are implicitly controlled for in our analysis. each rating session lasted between forty minutes and one hour, including the reading of the instructions and payment. raters were paid a show-up fee of $ and an additional $ payment for completing the task of rating all photos and providing demographic information. . . descriptive statistics we start with a total of subjects split evenly between employers and workers. our main unit of observation is employer-worker pairs, of which we have per session (four employers each bidding on four workers) for a total of pairs. however, a few subjects drop out of our sample. first, we exclude two pilot sessions held on december , from the main analysis. second, we drop a subject who self-identified as a non-student (an employer). third, we drop a subject who participated in our experiment twice, keeping the first instance (an employer) and dropping the second instance (a worker). fourth, we drop five employers who did not use the worker résumé information (that is, who did not click on the worker’s photo or résumé). including these observations does not significantly change the results. finally, we also drop two subjects (workers) who chose to withdraw from our study after the experiment. the final dataset consists of employers and workers for a total of employer-worker pairs. table provides the summary statistics for employers and workers by task, gender, and round. the employers’ outcomes across our three tasks appear comparable. in round , the average wage bid ranges from to . while the mean wage bid in data analysis is statistically lower than in data entry or bargaining (with t-test p-values of . and . , respectively), the difference of around four points on average is relatively small. similarly, the employers predict statistically lower performance in data analysis (in points) relative to the other two tasks (t-test p- value of < . ), but the differences are modest in size. female employers bid slightly higher than males, but the differences are not statistically significant. similarly, there are no significant gender differences in employers’ performance predictions and earnings in any of the tasks. the scale was expanded from a – point scale previously used in the literature (hamermesh and biddle , ) to a – point scale. summary statistics for rater demographic information can be found in the online appendix. [table about here] in round , male workers predict that they will perform better than female workers in the bargaining task (t-test p-value of . ). these predictions turn out to be correct, with males outperforming females by about points in this task. workers have significantly lower payoffs in data analysis than in the other two tasks in the first round (t-test p-value < . ). workers earn significantly higher payoffs than employers in data entry and bargaining (t-test p-values of < . and . , respectively), but employers earn significantly greater payoffs in data analysis (t-test p-value of . ). in round , the average wage bid ranges from to . females placed higher bids than males in the bargaining task (t-test p-value of . ). worker performance predictions in the second round do not significantly differ by gender. there is no significant difference between male and female worker performance in data entry or bargaining, but there is a significant difference between males and females in data analysis, with males outperforming females by about . questions. again, payoffs for workers are significantly lower in data analysis than in the other two tasks (t-test p-value of < . ). workers also make significantly higher payoffs than employers in data entry and bargaining (t-test p-values of < . and . , respectively). female employers earn significantly greater payoffs than female workers in data analysis (t-test p-value of < . ), but there is no difference between male employers and workers. table provides the summary statistics on subject attractiveness and other characteristics by gender for employers and workers. there are no statistically significant differences in attractiveness between either men and women or employers and workers in our sample. in our sample of workers, there are no statistically significant differences in any of the individual characteristics, on average. [table about here] before proceeding with more formal regression analysis, we estimate a simple correlation to test for the existence of the beauty premium in our experiment. table reveals the correlation between wage bids and attractiveness, without controlling for worker characteristics. when pooling all tasks, we find a significant positive correlation between the natural logarithm of the wage bid and worker attractiveness in both rounds. all specifications in table include date fixed effects with standard errors clustered by employer. [table about here] the results shown in columns and pool the data across tasks and include task fixed effects. panel shows that, on average, a one standard deviation increase in attractiveness increases the wage bid by about per cent in both rounds. when we further decompose our analysis by task, we do not find any statistically significant relationship between beauty and wage bids in either the data entry or the data analysis task (columns , , , and ). however, the beauty premium is statistically significant in the bargaining task (columns and ): a one standard deviation increase in attractiveness increases the wage bid by about per cent in each round. later in the paper, we elucidate the mechanisms behind this task-specific correlation. in panel of table , we investigate whether gender differences are more pronounced when we allow the beauty premium to vary for male and female workers. columns – show that the beauty premium in the first round is driven by the higher wages offered to comparatively attractive female workers. however, we cannot reject the hypothesis that the coefficients on the male and female ratings are identical. in the second round, attractiveness is marginally significant for men in bargaining, although again we fail to reject the hypothesis that the coefficients on the male and female ratings are equal. in data entry, more attractive women receive significantly higher wage bids than men (the coefficients on the male and female ratings are statistically different), which is possibly due to females reporting higher typing skills than males. . empirical strategy in this section, we outline a general framework for separating statistical discrimination from taste-based discrimination and testing whether statistical discrimination, if there is any, is based on rational or biased beliefs. to separate taste-based discrimination from statistical discrimination, we use the fact that the performance prediction captures the employer’s beliefs about actual worker performance, while the bid captures the value the employer derives from worker performance and from his or her attractiveness. thus, if only statistical discrimination is present (whether or not beliefs about performance are correct), then any effect of attractiveness on wage bids should operate only through the performance expectation. in other words, once we properly control for the performance prediction, worker’s attractiveness should have no further explanatory power in the case of pure statistical discrimination. if the effect of attractiveness on the employer’s wage bid is significant after controlling for the performance prediction, we conclude that there is taste- based discrimination, as a result of which employers bid more on more attractive workers even though they do not expect them to be more productive. because the employer’s bid for such a worker is likely to exhibit a nonlinear relationship with her performance prediction, we allow the performance prediction to enter the specification flexibly, as the within-employer rank of the worker’s performance prediction. log where indexes the employer and indexes the worker. we suppress the round subscripts for tractability reasons. the variable is the bid of employer on worker in round or round . the attractiveness rating is given by , and is employer ’s expectation of worker ’s performance. worker characteristics are captured by and include indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. the coefficients of interest are represented by , which captures taste-based discrimination, and the set , which captures statistical discrimination. the variable indexes the performance prediction rank of the worker. in all specifications, we include a set of task fixed effects whenever we combine multiple tasks in a single regression ( ), as well as a set of date fixed effects ( ). standard errors in equation ( ) are clustered by employer. the optimal bidding strategy in our setting is not analytically tractable and is likely to vary nonlinearly with the performance prediction. moreover, prior experimental literature finds that behavior consistently deviates from rational bidding strategies (e.g., cooper and fang, ). in order to determine whether employer beliefs about worker performance in a given task are correct on average, we test whether actual performance θ and attractiveness α are correlated using the following specification: log where indexes the worker and t indexes the task. we suppress the round subscripts for tractability reasons. the variable is the performance of worker in task t in round or in round . worker characteristics are captured by . the coefficients of interest are represented by , which captures the correlation between ability and attractiveness. in all specifications, we include a set of task fixed effects whenever we combine multiple tasks in a single regression ( ), as well as a set of date fixed effects ( ). standard errors in equation ( ) are clustered by worker. our design also allows us to examine the effect of information on the beauty premium. the two-round setting captures the way in which repeated interactions between employers and workers in the labor market increase the amount of available information over time. the first round can be thought of as a trial period, during which the employer has limited information to use in forming a belief about the worker’s future productivity. a more precise signal indicating the worker’s ability arrives later on, once past performance can be observed (for example, when the worker comes up for a review or renegotiates her contract). if attractiveness is used as a signal of ability , it should be less informative in the second round, after a worker’s actual performance is revealed. to test for this, we estimate equation ( ) separately in round and round . moreover, we include the worker’s past performance in the round regressions as an explicit test of whether employers update their beliefs and bidding behavior based on new performance information. finally, we extend the analysis in equations ( ) and ( ) as follows. first, we allow the coefficient on the attractiveness rating to vary by attractiveness quintile to test for non-linear effects. second, we separate the effects by gender to test whether the beauty premium may vary across male and female workers. . results . . the sources of the beauty premium in the first round we begin our analysis with the first round. the first round represents an environment with limited information in which prospective employers make predictions about worker performance based on worker photos and résumé characteristics. because we can observe these characteristics perfectly, we can test whether the information from the résumé helps to explain the correlation between attractiveness and wage bids we find in the absence of these controls. result : there is a significant beauty premium in the bargaining task in the first round. furthermore, the beauty premium in bargaining is largest for the most attractive workers (those in the top attractiveness quintile). in the other two tasks, the beauty premium is absent on average, but exists for the moderately attractive workers in data entry. support for result comes from table , which shows the relationship between the natural logarithm of the wage bid in round and worker attractiveness, conditional on worker résumé characteristics: indicators for student status (graduate or undergraduate), major, self-reported abilities (typing, analytical, and communications), race, and gender. all specifications in table also include date fixed effects with standard errors clustered by employer. columns and pool the data across tasks and include task fixed effects. column estimates the simple relationship between the wage bid and the attractiveness rating, while column breaks the attractiveness rating into quintiles to allow for a potential nonlinear relationship between beauty and wage offers. on average, a one standard deviation increase in attractiveness leads to a per cent increase in the wage offer. relative to the bottom quintile, workers in all four of the top quintiles receive higher wage bids, but the significant positive effect appears only for workers whose beauty rating falls into the th quintile (above-average looks, but not the most attractive). [table about here] when we further decompose our analysis, we observe that the beauty premium varies by task. in particular, on average, we do not find a significant effect of beauty on wage bids in either the data entry or the data analysis task (columns and ). in data entry, workers in the nd , rd , and th attractiveness quintile receive significantly higher wage bids relative to the bottom quintile (column ), with the moderately attractive workers ( th quintile) receiving the largest premium. on the other hand, none of the beauty quintiles receives a significantly higher wage than the first quintile in data analysis (column ). however, the coefficients are jointly significantly different from one another. for instance, moderately attractive workers ( th quintile) receive significantly higher wages than workers with below-average looks ( nd quintile), as well as those in the top attractiveness quintile (f-test p-values of . and . , respectively). on average, we find a beauty premium only in the bargaining task (column ): a one standard deviation increase in attractiveness increases the wage bid by per cent in the bargaining task. column shows that the beauty premium in the bargaining task is strongest for the top quintile (the most-attractive workers). we obtain similar results if we rank workers by attractiveness out of four in each session instead of using a continuous attractiveness variable: the beauty premium is still present only in bargaining with a unit increase in rank associated with an increase in the wage bid of % (p-value of . ). the rank results can be found in the online appendix. the fact that the beauty premium shows up most consistently in the task that was expected to be “beauty related” ex-ante but not in the tasks that were expected to be “beauty unrelated” suggests that it is performance expectations, rather than tastes, that explain the existence of the overall beauty premium. because employer expectations about the relationship between attractiveness and performance should play a role in the relationship between attractiveness and the results are robust to including employer fixed effects. the results are also not substantively different when we control for whether the workers’ photos or résumés were shown to the employers first. we do not include these specifications in the paper, but estimates are available upon request. an f-test reveals that the coefficients on the th and th quintiles are not statistically significant from one another. jointly, the two coefficients are statistically significantly different from zero (f-test p-value of . ). furthermore, the coefficients on the th and th quintiles are jointly significantly different from the coefficient on the nd quintile (f-test p-value of . ). an f-test shows that the three coefficients are marginally jointly significant (p-value of . ) and that the difference between the th and the th attractiveness quintiles is statistically significant (p-value of . ). an f-test reveals that the coefficient on the th quintile is also statistically significantly different from the coefficient on the nd quintile (f-test p-value of . ). wage offers, we next examine whether employers believe that more attractive workers are more productive in the three tasks. result : employers expect more attractive workers to be more productive in the bargaining task, but not in other tasks. these beliefs turn out to be incorrect. table estimates the relationship between an employer’s performance expectation and worker attractiveness. specifically, we regress the natural logarithm of the employer’s prediction of worker performance in round on the worker’s beauty rating or on the indicator that the beauty rating is in a given quintile. [table about here] when we pool the data across tasks, we do not observe a significant relationship between worker attractiveness and employer performance prediction (columns and ). as we anticipated, employers do not expect comparatively attractive workers to have a performance advantage in the data entry task (columns and ). we also do not find a significant relationship between the worker’s average attractiveness and expected performance in the data analysis task (column ). however, employers expect workers whose looks are in the nd quintile to perform significantly better than those in the bottom quintile (column ). a positive relationship between beauty and expected performance emerges in bargaining (column and ). a one standard deviation increase in attractiveness, on average, is associated with a % increase in the mean performance prediction. similarly, in a linear specification, a one standard deviation increase in the beauty rating results in a statistically significant . point increase in predicted performance. the linear results can be found in the online appendix. the effect appears to be driven by the high expectations for the most attractive workers: those in the th quintile are expected to perform % better in bargaining than the workers in the bottom quintile. once again, the linear specifications produce an even stronger positive relationship between beauty and predicted performance for the top attractiveness quintile (results available upon request). this finding is consistent with the “beauty-related” nature of the task, since workers can see their opponent’s photos during bargaining. table shows that employer expectations turn out to be incorrect in the bargaining task. we regress the natural logarithm of worker performance in round on the average beauty rating or on the indicator that the beauty rating is in a given quintile. in this specification, standard errors are clustered by worker. columns and (the bargaining task) also include a count variable for the number of bargaining periods during which trade was possible and control for the average difference between buyer value and seller cost across the three bargaining rounds. there is no systematic positive relationship between attractiveness and performance in any of the tasks, either on average or when we break the rating up into quintiles. linear specifications with worker performance in levels produce qualitatively similar results. the results also do not change substantively if we omit the top attractiveness quintile instead of the bottom quintile. [table about here] employers also expect the second quintile to perform significantly better than the top quintile in data analysis (f-test p-value of . ). the results do not change if we omit the top quintile of attractiveness instead of the bottom quintile from the regressions. thus far, we have established that the beauty premium in bargaining is at least partly explained by employer beliefs about performance and that these beliefs are incorrect. we next proceed to test whether there is any taste-based discrimination by explicitly controlling for employer beliefs about performance in the round wage bid (equation ). result : the effect of beauty on wage bids disappears once we control for employer performance predictions, suggesting that there is no taste-based discrimination in our setting. support for result comes from table , which estimates the effect of attractiveness on wage bids in round , controlling for the employer prediction of worker performance. beauty is no longer a significant determinant of the wage bid in any of the tasks. although the second and fourth quintiles are significant in the data entry task, the lack of a pattern in that regression suggests that the correlation is likely spurious. our results are robust to controlling for polynomials of the employer performance prediction in addition to the performance prediction ranks. [table about here] as explained in section , any residual relationship between beauty and wage bids can be interpreted as taste-based discrimination. its absence in our setting suggests that employers are unwilling to sacrifice profits by hiring workers who are relatively attractive but not more productive. overall, the evidence from tables – shows that the statistical component of the beauty premium in the first round bargaining task can be explained by employers’ biased beliefs about the performance of comparatively attractive workers, rather than tastes or rational statistical discrimination based on worker résumé characteristics. . . does learning about performance eliminate the beauty premium in the second round? recall that table documents a significant relationship between attractiveness and wage bids in the second round, comparable in magnitude to that in the first round. so far, the evidence suggests that employers use appearance as a signal of ability, at least for the task that might be perceived as favoring comparatively attractive workers. however, we have also shown that the employers’ beliefs are incorrect. therefore, we proceed to examine the relationship between wage bids and beauty after relevant information about worker-specific previous performance is revealed to employers. specifically, we estimate the effect of attractiveness on wage offers in the second round, with and without controlling for first-round performance information (see equation in section ). we hypothesize that, because we don’t observe a significant relationship between attractiveness and performance, we should observe a reduction in the beauty premium in the second round relative to the first, which would indicate learning. result : the beauty premium completely disappears in the second round. information about past performance and employer expectations about future performance are both significant predictors of wage bids in the second round. support for result comes from tables and . table shows that, even when we do not control for past performance or the performance prediction (columns , , , and ), beauty is no longer correlated with wage bids in any of the tasks. this pattern holds as we add controls for performance in round (columns , , , and ). given our earlier findings that (a) employers use attractiveness as a signal of performance in the first round and (b) there is no relationship between attractiveness and performance, the absence of a beauty premium in the second round suggests that employers have learned that attractiveness is not a signal of ability in this setting and thus no longer utilize it as information from which to form wage bids. the specifications that break up the beauty rating into quintiles produce similar results. in particular, we find no evidence of the beauty premium for any of the quintiles. similarly, restricting the sample to the sessions where the task in the second round was the same as in the first round does not change the results. [table about here] the estimated effects of performance in the first round on second round bids also confirm that there is substantial learning between rounds. past performance is a significant predictor of bids in all tasks, with employers bidding more on workers who performed better in the first round, all else equal. this is true even in cases where the first round task is different from the second round task, implying that employers expect performance in the three tasks to be correlated. table tests whether employer predictions of worker performance play a role in observed learning. columns – show that employers no longer expect relatively more attractive workers to outperform less attractive workers in bargaining. as before, employers do not expect there to be a beauty advantage in the other two tasks. in fact, the point estimates on the average beauty rating are negative in the bargaining and data analysis task, although the negative value is not statistically significant. columns – of table build on the results from table to show the effect of employer expectations on wage bids in the second round. once we control for employer performance predictions, past performance is significant only in the bargaining task, reaffirming that employers also fully incorporate first-round information into their performance expectations. thus, we conclude that learning eliminates the influence of beauty on the wage bid by changing employers’ expectations of the relationship between beauty and worker performance. [table about here] . . does the beauty premium vary by gender? table shows that the simple correlation between attractiveness and wages varies by gender. in this section, we present a more formal analysis of the gender differences in the beauty premium. result : there is no difference in the beauty premium by worker gender. however, employers’ performance expectations for comparatively attractive males and females differ from one another in data analysis and bargaining. these expectations turn out to be incorrect. interacting first-round performance with an indicator that the second-round task was the same as the first-round task does not change the results. support for this result comes from tables and . table estimates the beauty premium in the first round by task and gender. when we do not control for performance expectations (columns – ), we find a significant positive coefficient on female but not male attractiveness. however, the point estimates are very similar and the female and male beauty coefficients are not significantly different from one another. when we control for the rank of the performance prediction (columns – ), there is no significant relationship between attractiveness and bids for either gender, suggesting that any relationship between attractiveness and bids is again driven by statistical discrimination. [table about here] table estimates the gender-specific relationship between employer performance expectations and attractiveness (columns – ) and checks whether those expectations are correct (columns – ). although the beauty premium in bargaining does not vary by worker gender, employer expectations are different for comparatively attractive men than for comparatively attractive women. relatively more attractive males are expected to perform marginally worse than less attractive males in the data analysis task, all else remaining equal. furthermore, the expected beauty effects on data analysis performance for females ( . %) and for males (- . %) differ significantly from one another (f-test p-value of . ). on the other hand, the positive effect of attractiveness of the employer prediction in bargaining from table is driven by the expectation that relatively more attractive males will have a performance advantage: comparatively attractive males are expected to outperform less attractive males by % in bargaining. comparatively attractive females, on the other hand, are not expected to have a performance advantage in bargaining. the difference between males and females is statistically significant (f-test p-value of . ). as before, the employer expectations turn out to be incorrect in data analysis and in bargaining: neither comparatively attractive males nor comparatively attractive females have an actual performance advantage in any of the tasks (columns - ). [table about here] . conclusion we develop and execute a new method for determining the precise channel through which attractiveness leads to higher worker wages. our key insight is that having two measures, one that elicits expected worker performance and one that elicits employer willingness to pay, is both necessary and sufficient for separating statistical discrimination from taste-based discrimination without making restrictive assumptions. in addition, statistical discrimination can be further decomposed into biased beliefs and rational statistical discrimination if actual performance data are available. we run a laboratory experiment designed to elicit the two measures described above as well as to identify the stability of the beauty premium across a range of settings. while carefully controlling the overall experimental environment, we vary the tasks that workers must perform. our results indicate that the beauty premium is highly context-dependent: while we find strong evidence of a beauty premium in a bargaining task, there is no beauty premium in a data entry or data analysis task, on average. the beauty premium is composed entirely of statistical discrimination, which in turn can be explained by biased beliefs about the performance of comparatively attractive workers rather than rational expectations. it also does not appear to vary by gender: even though employers expect more attractive males to perform better in bargaining and worse in data analysis, these beliefs are incorrect. we also find a strong learning effect: the beauty premium disappears after worker performance is revealed, even in cases where the task changes. this suggests that, in our setting, employers use attractiveness at the hiring stage primarily as an imperfect signal of ability. thus, one implication of our results is that the beauty premium in the labor market may be explained by worker characteristics and employer performance beliefs that cannot be fully incorporated into the analysis of labor market outcomes in observational data. the absence of taste-based discrimination in our study may be explained in part by the minimal interactions between employers and workers in the experimental setting. thus, our results may not generalize to situations in which there is substantial face-to-face contact: employers may be willing to pay more attractive workers higher wages due to taste on average, but do not do so in our case because they do not interact with workers in person. however, internet-based interactions are an increasingly important part of the modern economy. they are pervasive in online labor markets, such as odesk, credit markets, such as prosper, and even fundraising venues, such as kickstarter. more generally, the spread of computers and the internet has transformed the modern workplace, with a growing fraction of workers spending all or most of their work time outside of the traditional office setting. because of this trend, laboratory experiments, where subjects interact with each other largely through computers, are ever more relevant outside of the laboratory. thus, our result pertaining to the absence of taste-based discrimination is highly applicable in these settings. because we do not find persistent biased beliefs in favor of more attractive people, the welfare losses from allowing beauty-based pay differentials are likely to be small in settings without substantial face-to-face interactions. moreover, if the spectrum of real-world tasks exhibits beauty-based performance differentials (which we do not observe in our study), eliminating such differentials may lower the quality of matching between workers and jobs, leading to welfare losses. testing for the existence of performance differentials across a number of jobs is an important step for future research. our understanding of the beauty premium may be enhanced by the introduction of face- to-face interactions between employers and workers and between the workers in the bargaining task in future experiments. further exploration of the potential gift-exchange mechanism behind the beauty premium may also be a fruitful direction for future research. references andreoni, j. and petrie, r., . beauty, gender and stereotypes: evidence from laboratory experiments. journal of economic psychology, vol. , – . ayres, i. and siegelman, p., . race and gender discrimination in bargaining for a new car, american economic review. ( ), – . becker, g., . the economics of discrimination. chicago: university of chicago press. berggren, n., jordahl, h. and poutvaara, p., . the looks of a winner: beauty, gender, and electoral success. journal of public economics, ( – ), – . berri, d. j., simmons, r., van gilder, j., and o'neill, l., . what does it mean to find the face of the franchise? physical attractiveness and the evaluation of athletic performance. economic letters, , – . biddle, j. and hamermesh, d., . beauty, productivity, and discrimination: lawyers’ looks and lucre. journal of labor economics, vol. 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working paper, university of illinois, urbana-champaign. duarte j., siegel, s. and young, l., . trust and credit: the role of appearance in peer-to-peer lending. review of financial studies, ( ), – . fischbacher, u., . z-tree: zurich toolbox for ready-made economic experiments. experimental economics, ( ), – . gächter, s. and renner, e., . the effects of (incentivized) belief elicitation in public goods experiments. experimental economics, , – . global workplace analytics, . the state of telework in the us – five year trend and forecast. http://www.globalworkplaceanalytics.com/whitepapers hamermesh, d. and biddle, j., . beauty and the labor market. american economic review, ( ), – . hamermesh, d., . beauty pays: why attractive people are more successful. princeton: princeton university press. mocan, n. and tekin, e., . ugly criminals. the review of economics and statistics, ( ), – . mobius, m. m. and rosenblat, t. s., . why beauty matters. american economic review, ( ), – . pallais, a., . inefficient hiring in entry-level labor markets. working paper, harvard university. ravina, e., . love & loans: the effect of beauty and personal characteristics in credit markets. working paper, columbia university. rosenblat, t., . the beauty premium: physical attractiveness and gender in dictator games. negotiation journal, ( ), – . solnick, s. j., and schweitzer, m. e., . the influence of physical attractiveness and gender on ultimatum game decisions. organizational behavior and human decision processes, ( ), – . wilson, r. k., and eckel, c. c., . judging a book by its cover: beauty and expectations in a trust game. political research quarterly, ( ), – . table treatment summary notes: round and round rows list all sessions, whether the task was the same or different in the second round. sessions with the same task in both rounds are listed in the row labeled “round = .” table summary statistics of experimental outcomes by task and gender notes: the means for employers are separated by male and female employers. the means for workers are separated by male and female workers. significance levels based on t-tests of differences between male and female subjects: * percent, ** percent. a mann-whitney u test that compares distributions produces similar results. # sessions #subjects # sessions #subjects # sessions #subjects round round round = data entry data analysis bargaining male female male female male female employers wage bid (points) . . . . . . average prediction (points) . . . . . . payoff (points) . . . . . . observations work ers own prediction (points) . . . . . * . * performance (points) . . . . . ** . ** payoff (points) . . . . . ** . ** observations employers wage bid (points) . . . . . * . * average prediction (points) . ** . ** . . . . payoff (points) . . . . . . observations work ers own prediction (points) . . . . . . performance (points) . . . . . . payoff (points) . . . * . * . . observations data entry data analysis bargaining panel : averages for round panel : averages for round table summary statistics of attractiveness and other subject characteristics notes: skills are measured on a scale of – , with representing excellent. resume gpa is measured on a scale of – , with representing the range . – . . major is for humanities; for social sciences; for natural sciences. significance levels based on t-tests of differences between male and female subjects: * percent, ** percent, *** percent. table the beauty premium by task for all workers and by worker gender in both rounds notes: the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. all regressions include date fixed effects. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. male female male female demeaned attractiveness rating - . . - . . analytical skills . *** . *** . . typing skills . *** . *** . . communication skills . * . * . . resume gpa . ** . ** . . observations exact gpa . ** . ** . . major . . . . share native english speakers . ** . ** . . employers workers panel : resume characteristics panel : other characteristics outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) all tasks data entry data analysis barg. all tasks data entry data analysis barg. attractiveness of worker . *** . . . ** . *** . . . ** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) observations r-squared . . . . . . . . attractiveness of worker if female . *** . . ** . *** . *** . *** . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) if male . . . . . - . . . * ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . . . . natural logarithm of employer wage bid round round panel : all workers panel : males versus females table relationship between an employer bid in round and worker attractiveness notes: round data only. mean wage bids (in points) for each task are reported in brackets below the task type. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. the p-values for the f-tests of joint differences of the coefficients on the attractiveness quintiles are reported in brackets below the estimates. all regressions include date fixed effects, indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) attractiveness of worker . ** . . . ** ( . ) ( . ) ( . ) ( . ) attractiveness quintiles: nd . . * - . . ( . ) ( . ) ( . ) ( . ) rd . . * . . ( . ) ( . ) ( . ) ( . ) th . ** . ** . . ( . ) ( . ) ( . ) ( . ) top attractiveness: th . . - . . ** ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . . . . natural logarithm of employer wage bid in round [ . ] [ . ] [ . ] [ . ] all tasks data entry data analysis bargaining table relationship between employer performance expectations and worker attractiveness in round notes: round data only. mean predicted performance (in points) for each task is reported in brackets below the task type. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. the p-values for the f-tests of joint differences of the coefficients on the attractiveness quintiles are reported in brackets below the estimates. all regressions include date fixed effects, indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) attractiveness of worker . - . - . . * ( . ) ( . ) ( . ) ( . ) attractiveness quintiles: nd - . - . . ** - . ( . ) ( . ) ( . ) ( . ) rd - . - . . - . ( . ) ( . ) ( . ) ( . ) th . - . . . ( . ) ( . ) ( . ) ( . ) top attractiveness: th . - . - . . * ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . . . . [ . ] [ . ] [ . ] natural logarithm of employer performance prediction in round all tasks data entry data analysis bargaining [ . ] table relationship between a worker attractiveness and performance in round notes: round data only. mean worker performance (in points) for each task is reported in brackets below the task type. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. the p-values for the f-tests of joint differences on the coefficients of attractiveness quintiles are reported in brackets below the estimates. all regressions include date fixed effects, indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. specifications ( ) and ( ) include an indicator for whether a trade was possible and control for the average difference between buyer value and seller cost across the three bargaining rounds. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by worker in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) attractiveness of worker . - . - . - . ( . ) ( . ) ( . ) ( . ) attractiveness quintiles: nd . - . . - . ( . ) ( . ) ( . ) ( . ) rd - . - . - . - . ( . ) ( . ) ( . ) ( . ) th . - . - . . ( . ) ( . ) ( . ) ( . ) top attractiveness: th - . - . - . - . ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . . . . natural logarithm of worker performance in round [ . ] [ . ] [ . ] [ . ] all tasks data entry data analysis bargaining table separating statistical from taste-based discrimination notes: round data only. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. all regressions include date fixed effects, indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) attractiveness of worker . - . . . ( . ) ( . ) ( . ) ( . ) attractiveness quintiles: nd . . * - . . ( . ) ( . ) ( . ) ( . ) rd . . . . ( . ) ( . ) ( . ) ( . ) th . ** . ** . . ( . ) ( . ) ( . ) ( . ) top attractiveness: th . . - . . ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] employer's performance prediction rank: nd . *** . *** . *** . *** . . . ** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) rd . *** . *** . *** . *** . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) top prediction rank: th . *** . *** . *** . *** . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) f-test p-value (joint sign.) [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . . . . natural logarithm of employer wage bid in round all tasks data entry data analysis bargaining table relationship between an employer bid in round and worker attractiveness notes: round data only. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. all regressions include date fixed effects, indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. table the role of employer performance expectations in the second round notes: round data only. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. all regressions include date fixed effects, indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. in cases where we pool the data across multiple tasks, we also include a task fixed effect. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) attractiveness of worker . . * . . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) log performance in round . *** . ** . *** . *** ( . ) ( . ) ( . ) ( . ) observations r-squared . . . . . . . . natural logarithm of employer wage bid in round all tasks data entry data analysis bargaining outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) all tasks data entry data analysis barg. all tasks data entry data analysis barg. attractiveness of worker - . . - . - . . . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) log performance in round . *** . ** . *** . *** . *** . . ** . ** ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) employer's performance prediction rank: nd . *** . *** . *** . ** ( . ) ( . ) ( . ) ( . ) rd . *** . *** . *** . ** ( . ) ( . ) ( . ) ( . ) top prediction rank: th . *** . *** . *** . *** ( . ) ( . ) ( . ) ( . ) observations r-squared . . . . . . . . natural logarithm of employer prediction in round natural logarithm of employer wage bid in round table relationship between employer bid in round and worker attractiveness by worker gender notes: round data only. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. the p-values for the f-tests of joint differences of the coefficients on the gender interactions are reported in brackets below the estimates. all regressions include date fixed effects and indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. robust standard errors are clustered by employer in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) data entry data analysis barg. data entry data analysis barg. attractiveness of worker if female - . . . ** - . . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) if male . . . . . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] employer's performance prediction rank: nd . *** . . ** ( . ) ( . ) ( . ) rd . *** . *** . *** ( . ) ( . ) ( . ) top prediction rank: th . *** . *** . *** ( . ) ( . ) ( . ) observations r-squared . . . . . . natural logarithm of employer wage bid in round table determinants of employer expectations about worker performance and actual performance by gender notes: round data only. the attractiveness coefficient should be interpreted as the effect of a one standard deviation change in beauty on the outcome variable. the p-values for the f-tests of joint differences of the coefficients on the gender interactions are reported in brackets below the estimates. all regressions include date fixed effects and indicators for student status (graduate or undergraduate), major, gpa range, self-reported abilities, race, and gender. column ( ) includes an indicator for whether a trade was possible and control for the average difference between buyer value and seller cost across the three bargaining rounds. robust standard errors are clustered by employer (columns – ) or worker (columns – ) in parentheses. significance levels: * percent, ** percent, *** percent. outcome variable: ( ) ( ) ( ) ( ) ( ) ( ) data entry data analysis barg. data entry data analysis barg. attractiveness of worker if female . . - . - . . - . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) if male - . - . * . *** - . - . . ( . ) ( . ) ( . ) ( . ) ( . ) ( . ) f-test p-value (equality) [ . ] [ . ] [ . ] [ . ] [ . ] [ . ] observations r-squared . . . . . . natural log of employer performance prediction in round natural log of actual worker performance in round evolutionary psychology www.epjournal.net – . ( ): - ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ original article cosmetics alter biologically-based factors of beauty: evidence from facial contrast alex l. jones, department of psychology, gettysburg college, pa, usa. school of psychology, bangor university, bangor, gwynedd, uk. email: alexjonesphd@gmail.com (corresponding author). richard russell, department of psychology, gettysburg college, gettysburg, pa, usa. robert ward, school of psychology, bangor university, bangor, gwynedd, uk. abstract: the use of cosmetics by women seems to consistently increase their attractiveness. what factors of attractiveness do cosmetics alter to achieve this? facial contrast is a known cue to sexual dimorphism and youth, and cosmetics exaggerate sexual dimorphisms in facial contrast. here, we demonstrate that the luminance contrast pattern of the eyes and eyebrows is consistently sexually dimorphic across a large sample of faces, with females possessing lower brow contrasts than males, and greater eye contrast than males. red-green and yellow-blue color contrasts were not found to differ consistently between the sexes. we also show that women use cosmetics not only to exaggerate sexual dimorphisms of brow and eye contrasts, but also to increase contrasts that decline with age. these findings refine the notion of facial contrast, and demonstrate how cosmetics can increase attractiveness by manipulating factors of beauty associated with facial contrast. keywords: facial contrast, sexual dimorphism, beauty, cosmetics, skin color ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ introduction our faces convey a wealth of information about us, but perhaps the clearest signal from our faces is that of our sex. male and female faces differ most obviously in terms of shape, following different developmental trajectories under varying hormonal influences (farkas, ). this sexual dimorphism in facial shape is linked to a multitude of biologically important traits, such as health (thornhill and gangestad, ) and attractiveness (perrett et al., ). research into facial sexual dimorphism and how it affects perceptions of attractiveness and mate choice (see rhodes, , for a review) has focused greatly on facial shape (thornhill and gangestad, ). however, surface reflectance properties, mailto:alexjonesphd@gmail.com facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - such as skin texture, are actually more important than facial shape for perceiving the sex of faces (hill, bruce, and akamatsu, ). the properties of the skin, such as color distribution (samson, fink, and matts, ) and luminance (jablonski and chaplin, ), also play a role in the perception of traits related to health and attractiveness (samson, fink, and matts, ; stephen, coetzee, and perrett, ). there is also a sexual dimorphism in facial coloration - women tend to have lighter skin than men, who are darker and ruddier (nestor and tarr, ), a difference consistent across different racial and ethnic groups (frost, ). aside from global sex differences in skin color, there are cues to sex within the coloration of our faces. contrast in particular is a vital component of visual perception, as it is the property encoded by the majority of neurons in the primary cortex (geisler, albrecht, and crane, ), and its role in evolutionary models of face perception has not been thoroughly studied. faces form a typical pattern of darker features and lighter skin (sinha, ), and elsewhere we have demonstrated that the difference in luminance between facial features (eyes and mouth) and skin—termed “facial contrast”—is sexually dimorphic (russell, ). female faces have higher facial contrast on average than males due to female skin being lighter than male skin, though female features are not lighter than male features. facial contrast correlates positively with ratings of femininity and negatively with masculinity, and alterations to facial contrast make an androgynous face appear male or female (russell, ). alterations to facial contrast also impact the attractiveness of faces. increasing the contrast of the eyes and mouth leads to higher attractiveness judgments for females, but attenuates the same judgments for males, with the reverse being true for decreases in contrast (nestor and tarr, ; russell, ). facial contrast also plays a role in perception of age, beyond more obvious cues such as wrinkles. porcheron, mauger, and russell ( ) demonstrated that aspects of facial contrast change with age, with the majority of feature contrasts decreasing as individuals grow older across a range of color sources, such as lip redness. porcheron et al. ( ) also showed that not only do these contrasts predict judgments of age, but that manipulating these contrasts can make faces appear younger or older depending on the direction of the manipulation. facial contrast therefore impacts perceptions of youth, which is a key component of female facial attractiveness as it is a cue to reproductive potential (jones, ). an extremely widespread behavior that increases female facial attractiveness is the use of cosmetics. cosmetics increase attractiveness in a variety of ways, such as through smoothing skin texture (samson, fink, and matts, ). however, when women apply cosmetics, they do so in a manner that consistently exaggerates the sex difference in facial contrast, by darkening features relative to the surrounding skin (etcoff, stock, haley, vickery, and house, ; russell, ). it is unlikely that the manipulation of facial contrast achieved by cosmetics is done by chance. the “received style” of cosmetics (russell, ), darkening features relative to the skin, is prevalent across modern societies as well as archaeological records, indicating it is consistent throughout history (corson, ). it is unsurprising that women are rated consistently as more attractive with cosmetics (cash, dawson, davis, bowen, and galumbeck, ; etcoff et al., ; mulhern, fieldman, hussey, lévêque, and pineau, ; nash, fieldman, hussey, lévêque, and pineau, ), or that women use cosmetics as a mate attraction technique (buss, ). as facial contrast decreases with age (porcheron et al., ), it is possible facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - that cosmetics may also function by making faces appear younger, increasing at least some of the contrasts that decline with age. cosmetics may beautify faces by modifying contrasts that are cues to sexual dimorphism and youthfulness, which are predictors of female mate value (jones, ). however, there remain aspects of facial contrast that are not understood. there exists a sexual dimorphism in both eyebrow thickness (i.e. the distance from the bottom edge to the top edge of the brow) and brow-to-eye distance (farkas and munro, ), with females possessing higher and thinner brows. some grooming behaviors of modern women already seem to simultaneously accentuate both these dimorphisms by plucking the brow from the bottom (aucoin, ), making this facial feature more feminine. lower brow thickness is also associated with greater attractiveness (kościński, ). because plucking reduces the density of eyebrow hairs, revealing more of the underlying skin, it may also result in decreased contrast between the brow and the surrounding skin. when ambiguous faces are classified as male, they tend to have darker eyebrows than faces classified as female (nestor and tarr, ). additionally, the luminance pattern of the eyes and the brows play an important role in classifying faces as male or female (dupuis-roy, fortin, fiset, and gosselin, ). these findings suggest there may be a sex difference in brow contrast - possibly due to the sex difference in the likelihood of plucking the brow. if this is the case, it may not be just be eye contrast that signals information about sex, but the combined contrast pattern of the eyes and brow. however, previous studies investigating sex differences in facial contrast (russell, ; stephen and mckeegan, ) have not investigated contrast around the eyebrow. we predict that, given the greater thickness of hair in male brows, there should exist a sexual dimorphism in brow contrast, with males having greater brow contrast than females. while other studies have examined the role that different color channels contribute to perceptions and classifications of sex (nestor and tarr, ; dupuis-roy et al., ), these studies have not specifically examined whether there are sex differences in facial contrast across features. for this reason, we investigate sex differences in luminance, red- green and yellow-blue contrasts for the eyebrows, eyes, and mouth, an approach used previously by porcheron et al. ( ) to examine changes in facial contrast with age. related, it is unknown whether contrasts that decrease with age are actually enhanced by cosmetics. we predict that cosmetics will increase color contrasts related to youthfulness for the mouth and eyes. however, for the brow, it is unclear how cosmetics may be used - if females have lower brow contrasts than males, they should decrease their brow contrast with cosmetics to enhance sexual dimorphism. however, this is a contrast that declines with age, and which correlates with perceptions of age. this may lead to a conflict of signaling attractiveness and youth, which we expand on later. further, other studies have found contradictory evidence to facial contrast playing a role in perceptions of certain traits. stephen, law-smith, stirrat and perrett ( ) found minimal evidence of an effect of mouth contrasts on perceptions of health, a trait linked with attractiveness (shackelford and larsen, ), and no evidence of sex differences in the effect of mouth contrast on perceptions of health. stephen et al. ( ; page ) suggested that the use of black and white images by russell ( ) could have eliminated important color cues to sexual dimorphism in facial contrast. a further suggestion by stephen et al. ( ) was that the effects of facial contrast on trait perceptions (russell, ; ) could be due more to facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - contrast from the eye region than from the mouth. we will provide evidence bearing on both of these suggestions. in experiment , we measure facial contrast in groups of caucasian and east asian individuals, measuring sex differences in color and luminance contrasts across three sources of contrast in the face: the brows, eyes, and mouth. we predict that luminance contrasts should be higher for the eyes and mouth in female faces, but lower for brow contrasts. then, in experiment , we examine the contrast changes in features across color and luminance channels before and after an application of cosmetics, to test whether cosmetics increase the sexual dimorphism in facial contrast, and alter those contrasts that decrease with age. we predict that cosmetics should increase contrasts that exaggerate sexual dimorphism, and also those that decrease with age. experiment – sex differences in facial color contrasts across three sets of faces (hereafter sets one, two and three) we calculated contrast for the eyebrows, eyes, and mouth, and examined differences between the sexes. we examined feature contrasts using the ciel*a*b* color space, which is modeled on human color perception, yielding information about skin color in perceptually relevant terms (weatherall and coombs, ). for all image sets, bangor university students were asked to remove all traces of facial cosmetics and jewelry, to tie their hair back from the face as necessary, and to maintain a neutral expression while looking into the camera. males were clean-shaven. models were paid £ for their participation. ethics statement all experiments presented in this article were carried out under the approval of the institutional review board at bangor university. materials and methods model demographics and image capture set . seventy-three females ( – years, m = . , sd = . ) and males ( – years, m = . , sd = . ) caucasian individuals, who self reported their ethnicity as white, were photographed using a canon eos d mii camera, with professional diffused lighting and reflectors. participants were photographed at a distance of approximately one meter, against a white background. we kept lens aperture (f . ), exposure time ( / s) and iso speed rating constant ( ) for all photographs. set . one hundred and thirty-four females ( – years, m = . , sd = . ) and males ( – years, m = . , sd = . ) caucasian individuals, who self reported their ethnicity as white, were photographed using the same camera as set one, but without reflectors and at a different time. participants were photographed at a distance of approximately one meter, against a white background. we kept lens aperture (f . ), exposure time ( / s) and iso speed rating constant ( ) for all photographs. set . seventy-nine females ( – years, m = . , sd = . ) and male ( – years, m = . , sd = . ) east asian students were photographed against a white background at a distance of approximately one meter with a nikon d camera, with a facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - camera-mounted flash angled º towards the ceiling. as before, lens aperture (f . ), exposure time ( / s), and iso speed rating ( ) were constant across photographs. as lighting differences are inconsistent across these three image sets, we do not directly compare values between faces of different sets (e.g., to say whether one race has greater contrast than another), but instead compare the sex differences in contrasts within sets only. all pictures were captured in a raw format. image analysis procedure all faces were manually landmarked using jpsychomorph, with a template of points (tiddeman, burt and perrett, ). the eyes, eyebrows and mouth were delineated for each face, with landmarks conforming closely to the edges of these features, as is standard practice when delineating faces for averaging and texture transforms. custom matlab software (version r b; the mathworks inc, massachusetts) was written to extract the landmarks surrounding the eyes, eyebrows, and mouth for each face. we also derived an area around each of the three features to form an annulus, which captured the surrounding skin coloration. all regions of interest (roi) are illustrated in figure . for the mouth region, this was achieved by expanding the region surrounding the mouth by a factor of two. for the eye region, we incorporated landmarks that delineated the nasal bridge and periorbital circles, and the landmarks that delineated the very bottom of the brow, creating an annulus that was approximately double the eye region. for the brow region, we raised the y-coordinate of the landmarks along the top of the brow by pixels to define the upper boundary of the brow annulus, and used the landmarks above the eye to define the lower boundary of the brow annulus. in this way, the roi’s were derived in exactly the same manner for each face, but were based upon the specific landmarks placed on each model. we converted the rgb image of each face into ciel*a*b* color space using matlab. this color space has three orthogonal dimensions: luminance (l*), red-green (a*), and yellow-blue (b*). pixel values for each color channel range from (l*, black; a*, green; b*, blue) to (l*, white; a*, red; b*, yellow), instead of the traditional – and - to + ciel*a*b* scales. this is because matlab represents l*a*b* color using unsigned bit integer values, which by definition cannot be negative (see baldevbhai and anand, , for a primer on digital representations of color spaces). matlab converts rgb images to ciel*a*b* color space using the profile connection space (pcs) described the international color consortium guidelines for conversion (icc; international color consortium, ). rgb values were converted using the pcs to ciel*a*b* color values, with a d illuminant white point reference. to calculate facial contrast, luminance values of pixels within both eye regions were averaged, as were the luminance values within brow features, as well as the luminance values of the lips. similarly, we separately averaged the pixel values of the annuli surrounding the eyes, brows, and the mouth. the average values from within both eye features were then averaged to produce a mean eye feature value, with the same process repeated for the brow features, eye annuli, and brow annuli. the contrast of each feature was derived using russell’s ( ) adapted michelson contrast, as follows: cl* = (skin l* - feature l*)/(skin l* + feature l*). values range from - to ; with positive values indicating the surrounding skin has a higher luminance value than the feature, and negative numbers indicating the reverse. these calculations were repeated for the a* and b* facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - channels. for red-green contrasts, a positive value indicates the surrounding skin is redder than the feature, while for yellow-blue contrasts a positive value indicates the surrounding skin is yellower than the feature. given that both ends of the contrast spectrum (i.e., positive and negative) can be interpreted as being of greater contrast, we provide means in table . however, unless otherwise stated, the majority of contrast values are positive (i.e., the skin has a greater color value than the feature). figure . an illustration of the roi’s used to extract color information for the eye, mouth, and eyebrow features note. dashed white lines denote feature areas, while solid black lines represent the annuli. eye and eyebrow features were calculated for both sides. results for each image set, in each color channel, we used a (feature: eyebrows, eyes, mouth) x (sex: female, male) mixed model anova to test for sex differences across different features. across all of these tests, we observed significant interactions (reported in table ) between feature and sex, indicating differences in contrasts between males and females across features. these interactions are explored further below, separately for each color channel. sex differences in feature contrasts across color channels and image sets are also illustrated in figure . luminance contrasts in set , the feature x sex interaction was driven by higher brow contrast in males compared to females, t( ) = . , p = . , d = . , and by females having significantly higher eye luminance contrast than males, t( ) = . , p = . , d = . . the same pattern was observed in set , with males having higher brow contrast than females, t( ) facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - = . , p < . , d = . , and females having higher eye contrast than males, t( ) = . , p < . , d = . , as well as in set , with higher brow contrast in males, t( . ) = . , p < . , d = . , and higher eye contrast in females, t( ) = . , p < . , d = . . across all sets, mouth contrast was numerically greater in females than males, although this was significant only for the east asian group (set ), t( ) = . , p < . , d = . , and not the two caucasian groups, both ts < . , ps > . , set d = . , set d = . . table . means, standard errors, and feature x sex interactions of contrast values across color channels and image sets image set ciel*a*b* channel sex feature feature x sex interaction eyebrows eyes mouth set (caucasian) luminance female . (. ) . (. ) . (. ) . * η p = . male . (. ) . (. ) . (. ) red-green female . (. ) . (. ) -. (. ) . * η p = . male . (. ) . (. ) -. (. ) yellow-blue female . (. ) . (. ) . (. ) . † η p = . male . (. ) . (. ) . (. ) set (caucasian) luminance female . (. ) . (. ) . (. ) . * η p = . male . (. ) . (. ) . (. ) red-green female . (. ) . (. ) -. (. ) . * η p = . male . (. ) . (. ) -. (. ) yellow-blue female . (. ) . (. ) . (. ) . * η p = . male . (. ) . (. ) . (. ) set (east asian) luminance female . (. ) . (. ) . (. ) . * η p = . male . (. ) . (. ) . (. ) red-green female . (. ) . (. ) -. (. ) . * η p = . male . (. ) . (. ) -. (. ) yellow-blue female . (. ) . (. ) . (. ) . * η p = . male . (. ) . (. ) . (. ) note. numbers in parentheses denote sem. all values are reported to d.p. due to the scale of contrast measurements. degrees of freedom for interactions: set , f( , ); set , f( , ); set , f( , ). significance of f-ratios: †p < . , *p < . . facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - figure . average contrasts across image sets, contrast sources, and color channels note. scales differ between color channels. asterisks indicate a significant sex difference in feature contrast values. error bars represent ± sem. as a measure of contrast is a ratio between two sources of color, it is unclear what causes the contrast. for example, it is possible skin luminance does not differ between the sexes, but females possess darker eyes and lips than males but lighter eyebrows. if this were systematic, it would cause the differences stated above. to illustrate this more clearly, we compared raw feature and annulus luminance values between sexes for the features in the significant comparisons above. across all of the image sets, there were no sex differences in raw eye feature luminance, all ts < . , but eye annuli were significantly lighter in females, all ts > . , ps < . , indicating the sex difference in eye contrast is driven by fairer skin in females (russell, ). further to this, across all image sets, the eyebrow feature was consistently darker in males, all ts > . , ps < . . eyebrow annuli was also darker in male faces, all ts > . , ps < . . darker brows led to greater contrast in male faces compared to lighter brows and lighter skin in female faces. we also observed lighter lips in east asian females, t( ) = . , p < . , but there was an even greater sex difference in the surrounding skin, t( ) = . , p < . , which drove the sex difference in luminance contrast around the lips. in set , there were also differences in luminance values - females had lighter lips, t( ) = . , p = . , but also had much lighter skin than males, t( ) = . , p < . . the sex difference in eye facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - and mouth contrast seems to be driven by lighter skin in females, while the sex difference in eyebrow contrast is caused both by lighter skin in females and darker brows in males. red-green contrasts in set , the feature x sex interaction was driven by males having greater red-green contrasts for the brows, t( ) = . , p < . , d = . , while in set , males had greater contrast for the brows, t( ) = . , p < . , d = . , and females had greater eye contrast than males, t( ) = . , p = . , d = . . in set , the interaction was caused by higher brow contrast in males, t( ) = . , p < . , d = . . mouth contrasts across sets did not differ between sexes, nor did other feature contrasts, all ts < . , all ps > . . yellow-blue contrasts the feature x sex interaction in set was driven by females having higher yellow- blue contrasts for the mouth, t( ) = . , p = . , d = . , though in set it was caused by males having higher brow contrast, t( ) = . , p < . , d = . . in set , males had greater brow contrast than females, t( ) = . , p < . , d = . , and females possessed higher eye contrast than males, t( . ) = . , p = . , d = . . other mouth contrasts were not significant, nor were other feature contrasts, all ts < . , all ps >. . discussion the results from this experiment refine the notion of sexual dimorphism in facial contrast. while russell ( ) demonstrated that female faces have greater mouth and eye contrast than males, we have further unpacked the cues to sexual dimorphism in the upper face area, finding a divergent pattern of luminance contrasts of the eyes and brow. while females possess greater eye contrast than males (russell, ), males possess greater eyebrow contrast than females, a difference consistent across race. the results with luminance contrast around the mouth are somewhat less clear. there was greater contrast in the female faces in all three sets (d = . in set , d = . in set , and d = . in set ). however, this sex difference was statistically significant only with the east asian faces (set ). however, russell ( ) and stephen and mckeegan ( ) found that females have greater mouth luminance contrasts than males in caucasian but not east asian faces. the effect size for the sex difference in mouth luminance contrast was approximately d = . in the caucasian face set of stephen and mckeegan ( ), and d = . in the caucasian face set and d = . in the east asian face set of russell ( ). to examine this further, we conducted a basic meta-analysis on the six reported d scores of mouth luminance contrast. using a random effects model (field, ), we found that the sex differences in mouth contrast were homogenous across samples, x ( ) = . , p = . . moreover, the average sex difference in mouth luminance contrast was d = . ( % ci [ . , . ]), sem = . , with a significant population effect size, z = . , p = . . given these results, we can conclude there is a sex difference in mouth luminance contrast, but that in general it is smaller than the sex difference in eye contrast, which, from the data in this study, and that of russell ( ), has an average sex difference of d = . ( % ci [ . , . ]), sem = . . this result also supports the third suggestion of facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - stephen et al. ( , p. ), who noted that perceptions of sexual dimorphism from facial contrast could stem more from the eye region than the mouth. we also found consistent differences when examining red-green contrast. males possessed higher red-green contrasts around the brows. this is possibly due to males having redder skin than females in general. consistently, males had higher yellow-blue contrast around the brows than women, but the samples differed on little else. the greater brow contrasts in male faces in all three color channels could be due to males having a higher density of eyebrow hairs. a lower density of hairs would reveal more of the underlying skin, resulting in a lower contrast with the surrounding skin. there were some findings that were inconsistent across image sets. in set , females had greater yellow-blue mouth contrasts than males, and in set females had higher red-green contrast than males. these inconsistent differences suggest a lack of sexual dimorphism in these color channels. experiment – contrast alterations with cosmetics the application of facial cosmetics allows an individual to alter their appearance in a multitude of ways. however, a typical cosmetics application, referred to as the “received style” (russell, ) follows a consistent pattern of increasing skin homogeneity (evenness of skin tone) and darkening of facial features, an effect consistent across cultures and historical records (corson, ). this exaggerates precisely the sexual dimorphism in facial contrast identified by russell ( ), and we predict should increase some of the contrasts shown to decrease with age (porcheron et al., ). the results from experiment refine the notion of sex differences in facial contrast, demonstrating a divergence in luminance contrasts of the eyes and brow. grooming behaviors involving the brow seem to be designed to reduce contrast - plucking is extremely common, and presumably decreases contrast by removing hairs, and is standard beauty advice (aucoin, ). indeed, brow thickness in female faces is negatively correlated with perceived attractiveness (kościński, ). however, this is a more enduring manipulation, affecting facial appearance both with and without cosmetics. indeed, this is possibly the reason for the sexual dimorphism in luminance contrasts observed in experiment . however, cosmetic products like eyebrow pencils are prevalent historically (corson, ) and are a staple in modern day makeup practices. these products are designed to darken brows, possibly reversing age related declines in brow feature contrast (porcheron et al., ). by examining how women typically apply cosmetics, we can affirm if sexual dimorphism in brow contrasts is relevant for a sexually dimorphic appearance, or whether the manipulation of the brows by cosmetics serves to alter contrasts associated with age. further to this idea, stephen and mckeegan ( ) identified that in female faces, perceptions of femininity are enhanced by higher red-green and lower yellow-blue mouth contrasts. these contrasts are modifiable by cosmetics, and we examine these changes here by incorporating other color channels as in experiment to provide a fuller understanding of the enhancement in facial contrast cosmetics achieve, and the multiple signal channels cosmetics likely act upon (e.g., sexual dimorphism or age). we make several predictions regarding the use of cosmetics here. first, we predict that women will apply cosmetics that will enhance sexual dimorphisms in eye and mouth luminance contrasts, likely by darkening the eyes and mouth and lightening the skin around these features (russell, ). we also predict that red-green and yellow-blue eye contrasts facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - should be increased with cosmetics, as they are contrasts that decline with age. cosmetics should reduce the red-green contrast of the mouth by increasing the redness of the lips, a manipulation that has been shown to make female faces appear more sex typical and attractive (stephen and mckeegan, ), and as it is a contrast that increases with age (porcheron et al., ), reduction of this contrast should cue youthfulness. similarly, we predict that the yellow-blue contrast of the mouth should be lowered by the use of cosmetics, as this contrast reduction is also associated with perceptions of sex typicality and attractiveness (stephen and mckeegan, ), and also increases with age (porcheron et al., ). if these predictions are supported, then cosmetics will enhance contrasts related to both sexual dimorphism as well as youth. for the brow feature, cues of sexual dimorphism and youth are in conflict. we demonstrated in experiment females have consistently lower luminance contrasts in the brow than males, but a reduction of brow contrast occurs with age. it is therefore difficult to predict whether cosmetics would increase brow luminance contrast to cue youth at the expense of a sexually dimorphic appearance, or lower brow luminance contrast to cue sexual dimorphism at the expense of youthfulness. method forty-four caucasian females ( – years, m = . , sd = . ), who self reported their ethnicity as white, were recruited as models. models removed all traces of cosmetics they were wearing, along with facial jewelry. models were then photographed with a natural appearance. we provided models with a range of popular cosmetics, all of the same brand. these included two shades of eyeliner and two shades of brow pencils, four varieties of mascara, six shades of foundation, ten shades of eyeshadow, and over ten varieties of lipstick. models were invited to apply cosmetics as they would for a “night out”, before being photographed again. this context was chosen to provide a common scenario in which females may use cosmetics to maximize their attractiveness (buss, ; singh, ), and has been used in previous research (russell, ). photographs were taken with a nikon d camera against a white background. lighting was standardized from a flash angled º towards the ceiling. for all photographs, camera settings were kept constant, including lens aperture (f . ), exposure time ( / s), and iso speed rating ( ). contrasts were derived and analyzed exactly as described in experiment . results we sought to examine the differences in contrasts brought about by an application of cosmetics. to do this, we used a (cosmetics: without, with) x (feature: brows, eyes, mouth) repeated measures anova for each color channel separately. as before, we examine the interactions, as we are interested in how features might diverge with an application of cosmetics. feature contrasts before and after an application of cosmetics are illustrated in figure . facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - figure . the interaction between cosmetics and features, illustrated across color channels note. asterisks represent a significant change in feature contrast values with cosmetics; error bars represent ± sem. luminance contrasts the predicted cosmetics x feature interaction was significant, f( , ) = . , p < . , η p = . . consistent with previous research, eye feature contrasts increased significantly with an application of cosmetics, t( ) = . , p < . , d = . , as did mouth contrasts, t( ) = . , p = . , d = . . we also observed a significant decrease in brow luminance contrasts, t( ) = . , p = . , d = . . as contrast is a ratio, we sought to examine whether females decreased brow contrast by darkening the surrounding skin or by lightening the brow feature itself. a further paired t-test between raw brow feature luminance values revealed this feature was marginally yet consistently lightened by an application of cosmetics, t( ) = . , p = . , d = . (without cosmetics luminance value m = . , sd = . , with cosmetics, m = . , sd = . ). the brow annulus was slightly darker with cosmetics, though not significantly, t( ) = . , p = . , d = . (without cosmetics luminance value: m = . , sd = . ; with cosmetics: m = . , sd = . ). it is unusual that cosmetic practices would specifically lighten the brow, as the majority of cosmetic products for the eyebrow are geared towards darkening the feature. additionally, the eyebrow annulus is comprised of regions that are modified by cosmetics in divergent directions. eye shadow is typically applied below the brow, and foundation is perhaps applied above. importantly, some evidence demonstrates that the area directly above the eye and below the brow, when darkened with cosmetics, increases perceptions of attractiveness (killian and peissig, ). to explore this further, we isolated the region of skin directly above the eye and below the brow, and calculated the raw luminance values in this area before and after cosmetics application. in figure , this is the region in the brow annulus directly under the eyebrow but above the eye, which we now refer to as the upper eye region. this area was darkened significantly with an application of cosmetics, t( ) = . , p < . , d = . (without cosmetics luminance value: m = . , sd = . ; with cosmetics: m = . , sd = . ), indicating that while the brow feature was altered directly with cosmetics, the facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - region under the brow was also manipulated (and to a greater extent), contributing to contrast alterations. this manipulation would serve to decrease eye contrast by darkening the adjacent area, thereby increasing sexual dimorphism in the brow feature at the expense of sexual dimorphism in the eye feature. red-green contrasts the predicted cosmetics x feature interaction was significant, f( , ) = . , p < . , η p = . . the interaction was driven by divergent changes in eye and mouth contrast. red-green contrasts were increased by cosmetics, t( ) = . , p < . , d = . . as expected, cosmetics decreased mouth contrasts even further (increasing the absolute value of contrast), t( ) = . , p = . , d = . , further enhancing the redness contrast of the mouth. the raw values of the upper eye region decreased (made greener) with cosmetics, t( ) = . , p < . , d = . (without cosmetics red-green value: m = . , sd = . ; with cosmetics: m = . , sd = . ), indicating a role in modulating eyebrow contrast. however, overall brow contrasts in this channel did not alter with cosmetics, t( ) = . , p = . . yellow-blue contrasts a further cosmetics x feature interaction was significant, f( , ) = . , p < . , η p = . . this interaction was again driven by changes in eye and mouth contrasts, which were both increased by cosmetics, eyes, t( ) = . , p < . , d = . , mouth, t( ) = . , p < . , d = . . an additional analysis of the upper eye region showed that pixel values in this area were reduced (made bluer) with cosmetics, t( ) = . , p < . , d = . (without cosmetics yellow-blue value: m = . , sd = . ; with cosmetics: m = . , sd = . ). brow contrasts in this channel did not alter with cosmetics, t( ) = . , p = . . discussion our predictions that cosmetics alter contrasts that enhance sexual dimorphism were partially supported. an application of cosmetics increased luminance contrasts of the eyes and mouth, but decreased luminance contrasts of the eyebrows, exaggerating differences in luminance between the sexes. it is notable that the faces with makeup had reduced rather than increased luminance contrast of the eyebrow, which is unusual. though lower eyebrow contrast is feminine, it is also typical of older faces, indicating that for this group of young adult participants, makeup may have enhanced femininity at the expense of youthfulness. although a marginal reduction of eyebrow feature luminance was detected, this is probably not the washing out of luminance this feature undergoes with age. both the evidence presented in experiment and the results of others (stephen and mckeegan, ) suggest that red-green contrasts of the mouth are not sexually dimorphic. however, when participants applied lipstick, the value of this contrast source was decreased, as lips became redder. other studies have shown that decreasing the red-green contrast of the mouth increases perceptions of femininity and attractiveness in females (stephen and mckeegan, ). why might this be? there are two possible answers to this question. the first is that red lips are youthful. the red-green contrast of the mouth increases with age, and, in older faces, decreasing this contrast makes a face look younger facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - (porcheron et al., ). as youth is a component of female attractiveness (jones, ), the red green contrast of the mouth is likely a cue to age and therefore attractiveness. that is, even though red lip color is not dimorphic, it is still a valuable cue to be accentuated for women's attractiveness. the second reason may relate to the motivational value of the color red. men find women both more physically and sexually attractive in the presence of the color red (elliot and niesta, ), and males engage in approach behaviors more often when viewing a female wearing the color red (niesta kayser, elliot, and feltman, ), and perceive women wearing red to have more sexual intent (guéguen, a). in non human female primates, the color red is used to signal the onset of ovulation across a variety of bodily regions, induced by increased blood flow from higher circulating levels of estrogen (dixson and herbert, ). this is a signal used by male conspecifics as an honest signal of ovulation (deschner, heistermann, hodges, and boesch, ). concordantly, human females wear more red clothing (beall and tracey, ) and cosmetics around ovulation (guéguen, b). it is perhaps unsurprising that the color red has been a popular choice for lipstick since antiquity (regas and kozlowski, ). the red-green contrast of the mouth, exaggerated by cosmetics, may function as a supernormal stimulus, cueing not only youth, but also information about sexual intent. our prediction that yellow-blue mouth contrasts would be reduced was unsupported. instead, cosmetics increased this contrast, indicating the skin was yellower than the lips, the reverse of the pattern shown by stephen and mckeegan ( ). though this contrast increases with age (porcheron et al., ), the increase in skin yellowness here may have an effect on perceived health. higher levels of skin yellowness in the form of carotenoids are perceived as more healthy (stephen, coetzee, and perrett, ), and so this yellowness increase may offset any alterations to perceived age brought about by this alteration. we found that cosmetics increased the red-green and yellow-blue contrasts of the eyes, making the skin redder and yellower than the feature. porcheron et al. ( ) demonstrated that these contrasts reduce with age. these results illustrate that cosmetics alter the color contrasts of features that are associated not only with sexual dimorphism, but also with youth, offering an additional explanation of how cosmetics beautify faces - by increasing cues to youth. finally, we observed no changes in brow contrast in other channels apart from luminance. this is surprising; given that in experiment we observed a consistent sex difference in all channels for brow contrast. however, luminance contrasts were still altered in sex typical directions, and the upper eye region was manipulated by cosmetics by darkening the area while making it greener and bluer. it is likely that when considering the contrast of the brow directly, with skin both above and below the eyebrow, a smaller effect of brow contrast manipulation was observed. however, the action of cosmetics like eye shadows, which darken the upper eye region, serves to increase eye contrast and simultaneously decrease brow contrast by lessening the contrast of the brow with the immediately surrounding skin. the analyses presented here show that cosmetics act on brow contrast both directly, by altering the brow feature, and indirectly, by manipulating areas directly around the brow. these findings extend those of russell ( ), illustrating that women apply cosmetics to alter sexually dimorphic contrast patterns across facial features by exaggerating the differences between males and females. further, cosmetics were used to facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - enhance contrasts related to youth and perceived sex typicality. in the case of eyebrows, the cues for these desirable traits are in apparent conflict: a signal of youth (higher contrast) is opposed to a signal of femininity (low contrast). in this case, the women in our sample chose to reduce contrast (by shadowing the area under the eye). the use of cosmetics products like eye shadow may in fact offer an explanation of the conflicting cues of femininity and youth that stem from the eyebrow feature. age may reduce the contrast of the feature, but femininity may be signaled more clearly from the region above the eye, a signal enhanced by the women in our sample. do cosmetics increase attractiveness? finally, it is important to consider whether the cosmetics applied by the models increased their attractiveness, which is a consistent finding (cash et al., ; etcoff et al., ; mulhern et al., ). jones and kramer ( ) utilized the same models as in this study, and had them rated for attractiveness in both cosmetics conditions by participants. models were rated as more attractive with cosmetics than without, t( ) = . , p = . , d = . (though see jones and kramer, , for a fuller discussion of this finding). additionally, observers find the same models optimally attractive with significant amounts of cosmetics when given the option to vary the amount of cosmetics on the face (jones, kramer, and ward, ). taken together, these findings show that the cosmetics used by the models successfully increased their attractiveness. general discussion we have demonstrated that luminance contrasts of the eyes and brow diverge consistently between the sexes, supporting our hypothesis that eyebrow contrast should be sexually dimorphic. this sexual dimorphism in contrast was exaggerated by the use of cosmetics, an application of which decreased brow contrast but increased eye contrast. we show that the area directly above the eye and below the eyebrow is darkened with cosmetics, reducing the brow contrast. darkening of this area results in increased attractiveness judgments of faces with cosmetics (killian and peissig, ). the contrast pattern of the eyes and brows influencing perceptions of sex typicality has been hinted at elsewhere. dupuis-roy et al. ( ) showed that the brow-eye region, especially the luminance properties of these features, is important for classifying face sex. observers are able to rely on this pattern even in the absence of other color cues to sex. importantly, the shape or brow-eye distance did not predict sex classification, with color information proving more reliable. we extend these findings by showing the sexual dimorphism in contrast in the upper face region is consistently different between males and females, and is a pattern manipulated by cosmetics. additionally, these findings offer some support to the suggestion of stephen et al. ( ) who stated that the effects of facial contrast on femininity and masculinity (russell, ) are due to contrast around the eyes more than the contrast around the mouth. we observed a larger effect of cosmetics on the eyes than the mouth (d = . , d = . , respectively), a finding consistent with the results of our meta-analysis of the size of the sex difference of these contrasts. the effect size of an application of cosmetics was also greater across the eyes than any other feature, regardless of the color channel, indicating amore extensive manipulation of this feature. indeed, the effect size for eye luminance contrast (d = . ) was greater than any observed facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - natural sex difference in contrast of this feature (d = . , . , and . for sets , , and , respectively). these findings may also explain why eye makeup alone increases attractiveness, while mouth makeup fails to do so (mulhern et al., ). further, the findings here contradict the alternative suggestion of stephen et al. ( ), who suggested the use of black and white images removes important color information when examining sexual dimorphism in facial contrast. by examining contrasts in all channels in experiment , we found no consistent evidence of sexual dimorphism in eye or mouth contrasts in color channels other than the luminance (l*) channel. these findings advance our knowledge of female mate value and mate attraction techniques. female mate value is tied to physical attractiveness, which itself is strongly linked to sexual dimorphism (i.e., femininity; o’toole et al., ; rhodes, ). given that the use of cosmetics by women enhances their facial contrast, making them appear more feminine, it is unsurprising that women use cosmetics as a primary method of enhancing appearance for initiating relationships (greer and buss, ), and receive more male attention when wearing cosmetics (guéguen, ). the above evidence might suggest that cosmetics function as supernormal stimuli, exaggerating feminine traits. in non-human animals, exaggerated sexual characteristics, such as lengthened tails (winquist and lemon, ), lead to greater mating success. though the lack of a sex difference in mouth contrast was surprising, and does not support the notion that cosmetics serve to enhance sexually dimorphism in facial contrast, the present results confirm that cosmetics can serve to make female faces appear supernormal by exaggerating attractive contrasts (e.g. reddened lips, stephen and mckeegan, ). these findings indicate cosmetics can increase attractiveness by acting on multiple facial signal channels, such as those of youth and femininity. including the eyebrow as a source of contrast in the current experiments showed this region is sexually dimorphic. by examining the eyes and eyebrows separately, we now find this area contains two different cues to dimorphism. however, it may be that because the majority of females modify their eyebrows via plucking or trimming, there is likely a cultural component that may be responsible for the sexual dimorphism observed here. data from a sample of faces in which eyebrows are not modified as part of a standard beauty practice would help clarify whether the dimorphism we observed is natural or artificial. however, reduced brow thickness is associated with increased attractiveness (kościński, ), regardless of the nature of the manipulation, and this reduction may be furthered by cosmetics. while lowered contrast in female eyebrows might enhance a desirable dimorphism, it may also enhance a potentially undesirable signal of aging. women might therefore be expected to use cosmetics for the eyebrows strategically, to either emphasize femininity on one hand, or something like energy and vigor on the other. however, popular cosmetic trends at the time of writing advise darkening of the brows, likely because contrast of the brow decreases with age. however, this may be more beneficial for older women (as are most cosmetic practices; see huguet, croizet, and richetin, ) - younger woman may appear more masculine as a result of adopting this practice. a similar conflict may have led to the increase in the yellow-blue contrasts of the mouth, which increase with age and were also increased by cosmetics. however, as stated, this may be due to contrast changes being brought about by foundations increasing the yellowness of the skin, a cue to health (stephen, coetzee, and perrett, ). facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - the present study has several limitations. first, the lighting and camera conditions were not constant across the image sets used in experiment , and so we were unable to compare the differences between image sets due to the lighting and camera differences, which affect the color properties of the images. however, this is also a strength of the study. the sex differences in facial contrast of the eyes and brow were consistent across varying lighting and camera scenarios, indicating a robust effect that is not susceptible to variance in image properties. second, we instructed females in experiment to apply cosmetics as if they were going on a “night out”, and so our findings apply to the cosmetics used in this context, and may differ from other makeup styles (e.g., day to day, job interview). however, other literature has shown consistent increases in facial contrast for a range of different makeup styles (etcoff et al., ), so it is likely our results generalize to the majority of cosmetics contexts, though the strength of the manipulation may vary under different circumstances. the lack of color calibration in our images could be viewed as problematic. studies investigating one dimensional color properties of surfaces such as faces require color calibration of the images (stephen et al., ). however, as our variable of interest (facial contrast) is a relative measure of color properties within the same image, the issue of color calibration is less relevant here. additionally, the application of cosmetics led to contrast changes. while the luminance channel differences are consistent with previous work (russell, ) and our own results, the a* and b* channel contrast changes could be caused by the limited range of cosmetics that were provided. despite this, there were consistent similarities with the contrast changes with age described by porcheron et al. ( ), in that feature contrasts that decrease with age seem to be enhanced by cosmetics. conclusions we have shown that feature contrasts of the eyes and brows diverge in a consistent pattern between sexes, with females having greater luminance contrast of the eyes, but lower luminance contrast of the eyebrows. women who applied cosmetics did so in a way that exaggerated these sex differences in feature contrasts. cosmetics also increased feature contrasts that decline with age, as well as contrasts that are associated with increased attractiveness and femininity, demonstrating the action of cosmetics on multiple signal channels in the face. these findings further our understanding of the biological bases of beauty by refining the notion of facial contrast and offer further explanation of how cosmetics beautify faces. acknowledgements: this research was supported by knowledge economy skills scholarships (kess). kess is a pan-wales higher-level skills initiative led by bangor university on behalf of the he sector in wales. it is part funded by the welsh government (esf) convergence program for west wales and the valleys. the funding body had no involvement in the present paper. received october ; revision submitted january ; accepted january facial contrast and factors of beauty evolutionary psychology – issn - – volume ( ). . - - references aucoin, k. 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( ). sexual selection and exaggerated male tail length in birds. the american naturalist, , - . electroporation markedly improves sleeping beauty transposon-induced tumorigenesis in mice original article electroporation markedly improves sleeping beauty transposon-induced tumorigenesis in mice s jung , , h-j choi , , h-k park , , w jo , , s jang , , j-e ryu , , w-j kim , e-s yu , and w-c son , the sleeping beauty (sb) transposon system is an important tool for genetic studies. it is used to insert a gene of interest into the host chromosome, thus enabling permanent gene expression. however, this system is less useful in higher eukaryotes because the transposition frequency is low. efforts to improve the efficacy of the sb transposon system have focused on the method of gene delivery, but although electroporation has recently attracted much attention as an in vivo gene delivery tool, the simultaneous use of electroporation and the sb transposon system has not been studied for gene transfer in mice. in this study, electroporation was used in a model of sb transposon-induced insertional tumorigenesis. electroporation increased the rate of tumor development to three times that of the control group. there was no difference in phenotype between tumors induced with the sb transposon system alone and those induced by the sb transposon and electroporation. electroporation therefore may be an efficient means of improving the efficacy of gene transfer via the sb transposon system. cancer gene therapy ( ) , – ; doi: . /cgt. . ; published online july introduction the sleeping beauty (sb) transposon system is a genetically engineered, insertional mutagenesis system consisting of two components: a transposon, which is a series of dna-mobile elements flanked by indirect repeat sequences, and sb trans- posase, which catalyzes mobilization and reintegration of the transposon into mouse genomic dna. , integration into the host chromosome provides prolonged expression of the transferred gene. however, the sb transposon system has proven less useful in higher eukaryotes because of their low transposition frequency. therefore, researchers have developed double- or triple-transgenic mice, as well as modified transposon systems. these methods usually require a large amount of time and effort. we applied electroporation to the sb transposon system to improve transposition frequency, as electroporation is relatively simple and easy to use, and may compensate for the reduced efficacy of the sb transposon system in eukaryotes, including living animals. to achieve successful transformation of the genetic character of the cell, two conditions must be satisfied: ( ) transfer of the gene of interest into the cell cytosol and ( ) stable expression of the gene in the host cell. gene transfer into the cells of living animal tissue has been carried out using agents such as viral vectors and cationic liposomes, which are effective tools for examining gene function and the behavior of biological macromolecules in the living body, and moreover, are relevant to gene therapy. – however, in the case of viral vectors, some limitations have been reported. first, there is the possibility of unwanted insertional muta- genesis and induction of the host immune response. in addition, the preparation of recombinant viral granules is cumbersome, and the efficiency is sometimes very low. also, the foreign genes introduced with adenoviral vectors are only expressed transiently. therefore, lipofection with cationic liposomes asso- ciated with anionic plasmid dna and endocytotic machinery has been attempted as a non-viral method of delivering foreign genes into cells in vitro. – however, endocytosed plasmid dnas are liable to be digested in the lysosome, and cationic liposomes have some cytotoxicity, which reduces the efficacy of this form of gene delivery. electroporation has recently attracted attention as an approach that enables efficient gene transfer and expression in designated regions of living organs without any observed toxicity. , initially, this technique was restricted to suspensions of cultured cells, as the electric pulses were administered using a cuvette-type electrode. currently, as various new types of electrodes are being developed, electroporation of chemicals or foreign genes can also be performed in vivo. – electroporation induces short and intense electric pulses that cause transient permeabilization of the cell membrane, resulting in direct access to the cell cytosol. these pulses elevate the trans-membrane potential to an extent that causes defects within the lipid bilayer of the cell in the targeted region. these pulses are applied through electrodes positioned within the targeted tissue. electroporation is a simple technique that can be successfully used for acute gene expression. it can be used to simultaneously transfect multiple different plasmids and/or sirnas in order to analyze the combined functions of genes, and it has a high transfection efficiency and low cytotoxicity. however, the level of gene expression dramatically decreases after injection of electroporated cells because the majority of the dna is degraded or cleared from the circulation. to overcome this problem, we used the sb transposon system together with electroporation. , the purpose of this study was to evaluate the possibility of establishing a transgenic tumor model using electroporation and the sb transposon system, and to assess the effect of electro- poration on the tumor model. the oncogenes c-myc and h-ras and a short hairpin rna targeting p were delivered subcuta- neously into c bl/ mice using the sb transposon system, with comparative pathology core, asan institute for life sciences, seoul, korea and department of pathology, university of ulsan college of medicine, asan medical center, seoul, korea. correspondence: professor w-c son, department of pathology, university of ulsan college of medicine, asan medical center, olympic-ro -gil, seoul, songpa-gu - , korea. e-mail: wcson@amc.seoul.kr received march ; revised may ; accepted june ; published online july cancer gene therapy ( ) , – & nature america, inc. all rights reserved - / www.nature.com/cgt http://dx.doi.org/ . /cgt. . mailto:wcson@amc.seoul.kr http://www.nature.com/cgt or without additional electroporation, and several analyses were conducted on the resulting tumors. materials and methods animals all animal studies were conducted according to relevant national and international guidelines. female -week-old c bl/ mice were purchased from orient bio (yongin, korea). all mice were housed at a laboratory animal facility at the asan institute for life sciences under specific, pathogen- free conditions and were used according to the guidelines of the institutional animal care and use committee of the asan institute for life sciences. plasmid construction plasmids encoding the sb transposase (ppgk/sb ) and transposon vectors (pt /bh) with multiple cloning sites between the two indirect repeat sequences (ir/drs) were used for this study. the ppgk/sb and pt /bh plasmids were a kind gift from drs david largaespada and perry hackett at the university of minnesota. the cdna encoding either c-myc or h-ras was inserted into the pcxegfp plasmid (kindly provided by dr masaru okabe at osaka university in japan), after which the entire transcriptional cassette was cloned into pt /bh. pt /shp /gfp , a transposon plasmid encoding a short hairpin rna against the tumor suppressor p , was generously given to us by dr john ohlfest at the university of minnesota. dna used for injection was prepared using the endofree plasmid maxi kit (qiagen, germantown, md, usa) according to the manufacturer’s instructions. dna plasmid injections the animals received a mixture of the three types of transposon and the plasmid encoding the transposase, as detailed above. the molar ratio of transposase-encoding plasmid to the transposon plasmids was : . the three transposon plasmids were combined in equal amounts ( mg total), and the transposase-encoding plasmid was added to the transposon mixture in a total volume of ml of phosphate-buffered saline. the dna mixture was collected using an insulin syringe ( g) and was injected subcutaneously near the right inferior mammary gland. the transposon genes and the transposase genes were and kb in size, respectively, rounded to the nearest kb. in vivo electroporation electroporation was conducted on two-thirds of the mice ( / ) that with the injection of the dna plasmids ( / ), and on another one-third ( / ) of the mice that were injected with the empty plasmid served as negative controls. rest of the animals ( / ) were injected with the dna plasmids without electroporation. the skin overlying the mammary gland was shaved, and the injection site was electroporated using cellectra (vgx international (seoul, korea)/inovio (blue bell, pa, usa)) containing three needle probes at . a for s (three pulses; pulse duration, ms per pulse; interval between pulses, s) in accordance with the manufacturer’s guidelines (figure ). animal pet imaging radiopharmaceutical preparation: decay-corrected radiochemical yields ranged from – %, and after high-performance liquid chromatography purification, the radiochemical purity was %± . % (mean±s.d.). the specific activity of the [ f]flu-deoxy-glucose (fdg) was greater than tbq mmol� . positron emission tomography (pet) scans were per- formed using a micropet focus system (concorde microsystems, figure . the method of electroporation and the mechanism through which electroporation can increase gene transfer. (a) the procedure of electroporation. oncogene-encoding plasmid dnas were injected near the right inferior mammary gland and electro- poration was conducted at that site. (b) the effect of electroporation on the cell membrane and permeability. short and intense electric pulses cause defects within the lipid bilayer of the cell, which enables genes or biomolecules to directly access the cell cytosol. after electroporation, genes are inserted into the host genome via the effects of the sb transposon system. figure . comparison of tumorigenesis in mice with or without electroporation. (a) the incidence of tumor development was much higher in the electroporated group than in the control group. (b) the day at which tumors were first detected. in the electro- porated group, the number of animals developing tumors conti- nuously increased over the course of the study, and tumor growth was relatively rapid. electroporation improves gene transfer by transposon s jung et al cancer gene therapy ( ), – & nature america, inc. knoxville, tn) with resolutions of . mm (radial), . mm (tangential) and . mm (axial) at the center of the field of view. each mouse was injected with . mbq ( . mci) or mbq ( mci) [ f]fdg into the tail vein, and -min static pet scans were obtained. each mouse was kept under isoflurane anesthesia during the uptake and scanning periods. a heating pad and heat lamp were used to maintain body temperature at c. pet images were reconstructed by osem d using a cut-off frequency of . cycles per pixel. no attenuation correction was applied. tumor monitoring and necropsy all mice were carefully examined at least twice a week to detect any tumors. the tumors were measured using a digital caliper. the tumor volume (v) in mm was calculated using the formula v ¼ l � w / , where l is the longest diameter and w is the tumor length perpendicular to l. when the w length of the tumor was greater than mm, the mice were humanely killed and underwent necropsy. during the necropsy, the tumor was excised along with the circumferential tissue for histopathology examination. histology and immunohistochemistry after macroscopic examination, the excised tissues were fixed in % neutral buffered formalin. the specimens were then embedded in paraffin and -mm-thick sections were cut and stained with hematoxylin and eosin (h&e). antibodies to immunohistochemical markers (all from abcam, figure . comparison of tumor volumes in mice with or without electroporation. (a) tumors in the electroporated group grew faster and reached a larger volume than those in the control group, as seen when necropsy was performed. (b) there were no particular differences in body weight loss between the two groups. electroporation improves gene transfer by transposon s jung et al & nature america, inc. cancer gene therapy ( ), – cambridge, uk) were also used to subtype the tumors as follows: cd ( : ), cd ( : ) and cd ( : ) for histiocytic sarcoma; desmin ( : ) and myogenin ( : ) for pleomorphic rhabdomyosarcoma; hmb ( : ) and s ( : ) for malignant melanoma; a-smooth muscle actin ( : ) for leiomyosarcoma; pan-cytokeratin ( : ), cytokeratin ( : ) and cytokeratin ( : ) for undifferentiated carcinoma; and cyclin-dependent kinase ( : ) and murine double minute (mdm ; : ) for pleomorphic liposarcoma. results tumor observation in negative control mice that were injected with empty plasmid before electroporation, no tumor development was observed. nine out of the mice that had undergone electroporation developed subcutaneous tumors, whereas tumors were observed in only three of the mice that did not undergo electroporation (figure a). the tumor incidence in the electroporated group, therefore, was three times as high as that in the control group. the nodular, subcutaneous neoplasms were first observed – days following injection of the plasmid dna. in the electroporated group, two mice began to develop tumors days after the dna injection, and by the st day post injection, tumors were observed in nine of these mice (one was detected on the th day, two on the th day, two on the th day and one on the th day). however, in the control group that did not undergo electroporation, tumors were observed on the th day post injection in two mice and on the th day in a third mouse (figure b). each tumor grew rapidly, and in the mice treated with electroporation, the tumors grew faster and were slightly larger figure . positron emission tomography (pet-ct) scanning of tumors. pet-ct images of subcutaneous neoplasms. (a) a coronal ct section and (b) a sagittal ct section. the tumor appears as the red-to-yellow-colored region (arrows) near the urinary bladder (red ball). figure . gross tumor characteristics. each tumor was located in the subcutaneous soft tissue at the site of injection of the dna plasmids. the tumors were smoothly demarcated by the surrounding peritoneum. no metastasis was observed. electroporation improves gene transfer by transposon s jung et al cancer gene therapy ( ), – & nature america, inc. than those seen in mice not treated with electroporation (figure ). animal pet imaging the subcutaneous tumors can be observed as a red-to-yellow region near the urinary bladder on transverse and coronal pet-computerized tomography images (figures a and b). gross and microscopic findings well-demarcated, round-to-ovoid nodules were detected in the subcutaneous soft tissue where the dna plasmids were injected (figure ). metastatic foci at non-injected sites were not observed. by h&e staining, the tumors were all poorly differentiated (figures a and b). the majority of tumor cells had a round-to-oval shape and pale, basophilic cytoplasm and hyperchromatic nuclei with prominent nucleoli. in particular, both epithelial and the mesenchymal components were observed simultaneously. the tumor also showed a high degree of cellularity, abundant mitoses, a large number of apoptotic cells and occasional multinucleated giant cells. areas of necrosis were seen in the center of the tumor on gross examination and by h&e staining. however, the overlying skin and its associated adnexa, including hair follicles, sebaceous glands and mammary glands, did not exhibit dysplastic changes. all tumors had the same morphologic features regardless of whether the mice underwent electroporation. immunohistochemical findings to investigate differences in the histological phenotypes of the tumors, immunohistochemistry was performed for different markers. as summarized in table , there was no difference in the expression of any of these markers between the tumors of the mice that underwent electroporation after plasmid dna injection and those that did not. pan-cytokeratin was the only marker expressed by the tumor cells, suggesting an epithelial tumor origin (figures a and b). positive immunostaining for the other markers was only observed in the tumor-associated stroma and not in the tumors. discussion dna for three oncogenes was subcutaneously injected into mice using the sb transposon system, along with a plasmid encoding transposase. two-thirds of the mice ( / ) were then injected with dna plasmids. even though the mice were not transgenic, a total of animals ( / ) developed tumors at the injection site. of these mice, nine had undergone electropora- tion and three had not. animals that received elctroporation but injected with empty plasmids did not develop any tumors. the rate of tumorigenesis was thus three times higher in the electroporated mice, suggesting that electroporation increases the accuracy and efficiency of gene transfer into target tissue. calculation of the tumor volumes also revealed that tumors in mice treated with electroporation grew faster than the tumors that developed in mice not treated with electroporation, although this difference was not statistically significant. these results suggest that electroporation increases gene transfer, thus leading to the higher expression of those genes in the electroporated tissue. although the sb transposon system is an innovative approach for transferring genes into tissue, there has been some data suggesting that the sb system is not as powerful in eukaryotic cells. various attempts have been made to address this problem, such as researchers attempting to produce a more powerful sb transposon system using transgenic animals in which the cancer-related genes are knocked out. however, this method is both time-consuming and complicated. in contrast, electroporation is a simple and rapid method of impro- ving the frequency of transposition. our results suggest that the simultaneous use of electroporation and the sb trans- poson system could be an extremely valuable tool for all types of gene transfer studies, including mouse tumor model development. figure . comparison of the tumors by hematoxylin and eosin staining. there was no difference in histological features between the tumors of (a) the electroporated mice and (b) the control mice. all tumors were poorly differentiated carcinomas. all images are shown at � magnification. table . comparison of tumors by immunohistochemistry ihc profile target tissue ihc antibody ep no ep epithelium pan-cytokeratin þ þ cytokeratin � � cytokeratin � � muscle myogenin � � desmin � � alpha sma � � hematopoietic cells cd � � cd � � cd � � melanoma melanoma � � s � � adipose tissue cdk � � mdm � � adenocarcinoma cea � � abbreviations: cea, carcino-embryonic antigen; ep, electroporation; ihc, immunohistochemistry; sma, smooth muscle actin. þ ¼ positive; � ¼ negative. electroporation improves gene transfer by transposon s jung et al & nature america, inc. cancer gene therapy ( ), – to compare the features of the tumors in each group, h&e staining and immunohistochemistry were performed. on the h&e stains, all the tumors had the same appearance, in which epithelial tumor cells were mixed together with spindle-shaped tumor cells. the immunohistochemistry results for the tumors of the electro- porated mice were identical to those of the control group, indicating that electroporation does not affect the pathological characteristics of the resulting tumors. the fact that electropora- tion increased the efficacy of gene transfer without altering the tumor type is an advantage of the electroporation method of generating a tumor model. although xenograft models and genetically engineered mice can mimic human cancer progression, the mouse model systems currently used do not exactly correspond to the human system because their genetic backgrounds are not wild type. – a hallmark of human cancer is its genetic complexity, which indicates that a number of different mutations are commonly involved. the complex genetic alterations in different cancers give rise to many histological subtypes, which accounts for the heterogeneous nature of a given type of neoplasm. as diverse tumor phenotypes can be induced by different gene combinations, combining the electroporation method and the sb system may be a novel method of expanding the repertoire of currently available mouse tumor models. during necropsy, macroscopic examination was conducted on all tissues, including the spleen, liver, stomach, intestine, mesenteric lymph node, kidney, adrenal gland, urinary bladder, lung, heart and brain. however, metastasis to these tissues was not observed in our model. in conclusion, electroporation after delivery of oncogenes via the sb transposon system increased the rate of tumorigenesis to %, which is three times higher than the rate of tumorigenesis observed without electroporation. the electroporation method may therefore be used for the continued development of mouse tumor models by altering the site of injection or the administered oncogenes. conflict of interest the authors declare no conflict of interest. acknowledgements this study was supported by a grant from the korean health technology r&d project, ministry of health and welfare, republic of korea (hi c and hi c ). vgx international kindly provided cellectra (the electroporation device). references belur lr, podetz-pedersen km, sorenson bs, hsu ah, parker jb, carlson cs et al. inhibition of angiogenesis and suppression of colorectal cancer metastatic to the liver using the sleeping beauty transposon system. mol cancer ; 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: – . andrechek er, nevins jr. mouse models of cancers: opportunities to address heterogeneity of human cancer and evaluate therapeutic strategies. j mol med (berl) ; : – . electroporation improves gene transfer by transposon s jung et al & nature america, inc. cancer gene therapy ( ), – electroporation markedly improves sleeping beauty transposon-induced tumorigenesis in mice introduction materials and methods animals plasmid construction dna plasmid injections in vivo electroporation animal pet imaging tumor monitoring and necropsy histology and immunohistochemistry results tumor observation animal pet imaging gross and microscopic findings immunohistochemical findings discussion acknowledgements references the generalized sleeping beauty problem: a challenge for thirders roger white a nalysis . , april , pp. – . © roger white grim, p. . there is no set of all truths. analysis : – . grim, p. . on sets and worlds: a reply to menzel. analysis : – . grim, p. . the incomplete universe . cambridge, ma: mit press. hájek, p., j. paris, and j. shepherdson. . the liar paradox and fuzzy logic. journal of symbolic logic : – . kripke, s. . outline of a theory of truth. journal of philosophy : – . reprinted in recent essays on truth and the liar paradox , ed. r. martin. oxford: oxford university press. priest, g. . the logic of paradox. journal of philosophical logic : – . priest, g. . in contradiction . the hague: martinhus niijhof. reinhardt, w. . some remarks on extending and interpreting theories with a partial predicate for truth. journal of philosophical logic : – . restall, g. . arithmetic and truth in ukasiewicz’s infinitely valued logic. logique et analyse : – . van fraassen, b. . presupposition, implication, and self-reference. journal of philosophy : – . van fraassen, b. . truth and paradoxical consequences. in the paradox of the liar , ed. r. martin, – . new haven: yale university press. l blackwell publishing ltd.oxford, uk and malden, usaanalanalysis - blackwell publishing ltd.april articlesroger white the generalized sleeping beauty problem the generalized sleeping beauty problem: a challenge for thirders r oger w hite the two candidate answers to the sleeping beauty problem (elga ) are / and / , the proponents of which are known as halfers and thirders. by considering a generalization of the original puzzle, i pose a challenge to thirders: when the main arguments for the answer / are extended to the generalized case they have an unacceptable consequence, whereas extending the halfer’s reasoning turns out rather nicely. . the original sleeping beauty problem on sunday sleeping beauty learns that she will be put to sleep for the next two days. if the fair coin that is to be tossed lands heads, she will be awakened briefly on monday. if it lands tails, she will be awakened briefly on monday, returned to sleep with her memory of that awakening erased, then awakened briefly again on tuesday. when she awakens on monday, what should beauty’s credence be that the coin landed heads? the generalized sleeping beauty problem a natural first answer is / . since beauty knew no more than that the coin was fair, her initial credence that the coin would land heads should have been / . has she learnt anything new that should alter this judg- ment? she knew all along that she was to be awakened briefly during the experiment at some time. so it is no news to her when she finds herself awake at an unknown time. when awakened she may learn something that she would express as ‘i am awake now .’ but it is difficult at best to see what bearing this could have for her on whether the coin landed heads. hence surely her credence that the coin landed heads should remain at / . nevertheless, the majority of philosophers who have written on the puzzle have concluded that the correct answer is / . thirders include arntzenius ( ), dorr ( ), elga ( ), hitchcock ( ), horgan ( ), monton ( ) and weintraub ( ). lewis ( ) is the only explicit halfer that i know of in print, but bradley ( ) challenges dorr’s argument for the / answer. there have been two main arguments for / , which i will only briefly sketch here: the elga argument : when beauty wakes up she knows that she is in one of the following ‘predicaments’: h mon : the coin landed heads and it is now monday. t mon : the coin landed tails and it is now monday. t tue : the coin landed tails and it is now tuesday. let p be the rational credence function for beauty when she wakes up on monday. that her credence in the coin having landed heads should be / follows from two lemmas: ( ) ( ) proof : ( ) entails that p( t mon ) = p( t tue ). ( ) entails that p( h mon ) = p( t mon ). so p( h mon ) = p( t mon ) = p( t tue ) = / , since these predicaments are exhaustive and incompatible at a time. beauty knows the coin landed heads if and only if she is in h mon , hence her credence that it did should be / . argument for ( ) : given that the coin has landed tails, and hence that she is in either predicament t mon or t tue , beauty has no more reason to suppose that she is undergoing the first tails waking rather than the second, or vice versa. hence she should divide her credence equally. argument for ( ) : it should make no epistemic difference to beauty if the coin is tossed before or after the first waking to determine whether she will be awakened again on tuesday. supposing then that it’s the latter, if beauty is informed that it is monday and hence that she is in either h mon p or p ormon mon tue tue mon tuet t t t t t( ) = ( ) p ormon mon monh h t( ) = roger white or t mon , her credence that she is in h mon should equal her credence that a fair coin which is yet to be tossed will land heads, namely / . the arntzenius-dorr argument : consider a variant case: modified story : exactly as in the original story, except that if the coin lands heads then beauty is awakened again on tuesday (her memory of the earlier waking erased). but after a brief pause she has an experience by which she can verify that the coin has landed heads and it is tuesday. upon waking on monday beauty’s credence should be divided evenly among the four predicaments: { h mon , h tue , t mon , t tue }. when she rules out h tue by failing to have the distinguishing experience, she learns nothing that should affect her distribution of credence among the remain- ing possibilities. hence she should have credence of / in each. since the total information that beauty has to go on now – that she is in one of the three predicaments: { h mon , t mon , t tue } – is the same in the original puzzle in which being awake in h tue is never an open possibility for her, the answer should be / in the original problem also. . the generalized sleeping beauty problem the challenge that i have for thirders arises from the following generali- zation of the original puzzle setup. a random waking device has an adjustable chance c ∈ ( , ] of waking sleeping beauty when activated on an occasion. in those circumstances in the original story where beauty was awakened, we now suppose only that this waking device is activated. when c = , we have the original sleeping beauty problem. but if c < , the case is significantly different. for in this case beauty cannot be sure in advance that she will be awakened at all during the experiment. when she does wake up she clearly gains some relevant information. for she has a greater chance of being awakened if the coin lands tails, since she will in that case have two opportunities instead of one in which the device much the same argument was arrived at independently by arntzenius ( ) and dorr ( ). in arntzenius’ version, in htue beauty is not strictly awake but enjoys a vivid dream whose only phenomenological difference from waking experience is that pinching herself doesn’t hurt. in dorr’s version, if the coin lands heads she is given only temporary amnesia after her monday wakening, so that part way into htue her memories flood back. another difference of debatable relevance is that the version of the unmodified story that dorr addresses has beauty waking on tuesday if the coin lands heads with her memories intact (in elga’s and arntzenius’ versions she remains asleep for two days.) dorr appeals to sorites-style reasoning to support the equivalence of the two cases. my interpretation of the argument more closely follows arntzenius’ presentation. the generalized sleeping beauty problem might wake her. so even ardent halfers must agree that in this case beauty’s credence should shift toward the coin’s having landed tails. but let’s consider how elga’s argument should be extended to the case where c < , considering the two crucial lemmas in turn. ( ) once again, it appears that if beauty were to awaken and learn that the coin landed tails, she should divide her credence equally between tmon and ttue. for she knows that if the coin lands tails, the waking device is activated on monday and again on tuesday, with the same chance of her waking on each occasion. ( ) now we suppose that beauty learns just that it is monday. if we can suppose without crucially altering the case that the coin is yet to be tossed, it seems that her credence that it is monday and the coin lands heads, i.e. that she is in hmon, should be / . for she knows that whether she is depends on whether a fair coin that is yet to be tossed lands heads. so we appear to have the required assumptions ( ) and ( ) to derive the answer / . at any rate, we have no less reason to follow elga’s reasoning in the generalized case than we did in the original one. if we trust elga’s original argument we should conclude that beauty’s credence on monday that the coin landed heads should be / , regardless of what value c takes. we get the same result by extending the arntzenius-dorr argument. first we modify the case by supposing that if the coin lands heads, then on tuesday the waking device is activated again except that if awakened then, beauty can soon discern that she is in predicament htue. it appears that upon waking on monday she should first distribute her credence equally among the four predicaments. the fact that she only has a chance of c < of being awakened on any of these four occasions cannot affect the case. so once she has determined that she is not in htue, her credence that she is in hmon should shift to / . hence we arrive by the reasoning above that in the case which does not include htue as a possibility for her to be awake in, her credence that she is in hmon and hence that the coin landed heads should be / . so according to the elga and arntzenius-dorr arguments then, the introduction of variable c has no effect on the answer to the problem. but this, i submit, cannot be right. as we have noted, if c < then when beauty wakes up she clearly does gain some information, namely w: beauty is awake at least once during the experiment. horgan ( ) presents an argument he identifies as being in the same spirit as dorr’s but without the appeal to a modified case. he suggests that when beauty wakes up she should assign prior probabilities of / to each of the ‘statements’ {hmon, htue, tmon, ttue}. her current probability is obtained by assigning zero to hmon, and renormalizing to give / to the others. in so far as i understand the rationale being applied here, the conclusion will be unaffected by lowering the value of c. so horgan’s argument faces the same problem as arntzenius’ and dorr’s. roger white and this is clearly relevant to whether h: the coin landed heads. for the likelihood of w is greater given ∼h than given h. any answer must take into account the impact of this information on beauty’s credence. but now the force of this impact must depend partly on the value of c. for the difference between the likelihoods p_(w|h) and p_(w|∼h) increases as c decreases (where p_ is beauty’s rational cre- dence function prior to waking). the degree to which beauty has a better chance of being awakened given two opportunities rather than one depends on how small c is. so whatever else we might say about beauty’s rational credence in h when she wakes up, it should vary to some degree with the value of c. this is a result that the thirder, insofar as he follows the elga and arntzenius-dorr arguments, cannot accommodate. from the sorry plight of the thirder, let’s turn to the happier results of the halfer. halfers are suspicious of any shift in credence that is not in response to new relevant information. so in the generalized case they insist that beauty should simply update her credence in the standard way by conditionalizing on her strongest new information, namely w. beauty’s new credence in h should be here we get an interesting result: as c → , p(h) → / (the halfer’s answer to the original problem) as c → , p(h) → / (the thirder’s answer to the original problem) on the halfer’s analysis, the / answer is correct only at the limit as the chance of being awakened on any occasion gets arbitrarily small. we can make the difficulty for the thirder more dramatic by considering a modified case. suppose that c = . , but whereas if the coin lands heads, the waking device is activated only on monday, if it lands tails the device is activated once a day for twenty-five days. in this case if the coin lands tails, beauty’s chance of being awakened at least once during the experiment is greater than . , while on heads it is only . . this dramatic difference in likelihoods should surely make a difference to beauty’s credence when she wakes up. yet according to the thirder’s arguments, her credence should be no different from the credence in the case in which c = , where there is no difference in these likelihoods at all. p p p p p p p p since h h w h w h h w h h w h c c c c c ( ) = ( ) = ( ) ( ) ( ) ( ) + ( ) ( )[ ] = ( ) ( ) + ( ) - -( )( )[ ] = -( ) >( ) _ _ _ _ _ _ ~ _ ~ when betting odds and credences come apart analysis . , april , pp. – . © darren bradley and hannes leitgeb without having diagnosed the exact error in the elga and arntzenius- dorr arguments, the challenge i have raised should undermine their case for / . new york university new york, ny - , usa roger.white@nyu.edu references arntzenius, f. . some problems for conditionalization and reflection. journal of philosophy : – . bradley, d. . sleeping beauty: a note on dorr’s argument for / . analysis : – . dorr, c. . sleeping beauty: in defence of elga. analysis : – . elga, a. . self-locating belief and the sleeping beauty problem. analysis : – . hitchcock, c. . beauty and the bets. synthese : – . horgan, t. . sleeping beauty awakened: new odds at the dawn of the new day. analysis : – . lewis, d. . sleeping beauty: reply to elga. analysis : – . monton, b. . sleeping beauty and the forgetful bayesian. analysis : – . weintraub, r. . sleeping beauty: a simple solution. analysis : – . thanks to cian dorr, adam elga, matt kotzen and sydney white for conversations about sleeping beauty. blackwell publishing ltd.oxford, uk and malden, usaanalanalysis - blackwell publishing ltd.april articlesdarren bradley & hannes leitgeb when betting odds and credences come apart when betting odds and credences come apart: more worries for dutch book arguments darren bradley & hannes leitgeb if an agent believes that the probability of e being true is / , should she accept a bet on e at even odds or better? yes, but only given certain conditions. this paper is about what those conditions are. in particular, we think that there is a condition that has been overlooked so far in the literature. we discovered it in response to a paper by hitchcock ( ) in which he argues for the / answer to the sleeping beauty problem. hitchcock argues that this credence follows from calculating her fair betting odds, plus the assumption that sleeping beauty’s credences should track her fair betting odds. we will show that this last assumption is false. wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ document resume ed se author girod, mark; rau, cheryl title appreciating the beauty of science ideas: teaching for aesthetic understanding. pub date - - note p.; paper presented at the annual meeting of the american educational research association (new orleans, la, april, ). pub type reports research ( ) speeches/meeting papers ( ) edrs price edrs price mf /pco plus postage. descriptors *aesthetic values; curriculum development; educational objectives; elementary secondary education; *science instruction abstract a large body of literature exists in which scientists describe their field as beautiful and the work they do as inspired and passionate. science teaching should strive to foster learning of substantive and powerful science ideas in ways that connect to the beauty inherent in those ideas. the conception of learning science in the study, that of learning of aesthetic understanding, achieves this goal by building on a framework of aesthetic experiences of understanding, pedagogy designed to foster it, and the results of a pilot study designed to investigate its effectiveness. statistical results suggest a positive effect from the pedagogy experiences of learning for aesthetic understanding. (author/khr) reproductions supplied by edrs are the best that can be made from the original document. appreciating the beauty of science ideas: teaching for aesthetic understanding mark girod and cheryl raul michigan state university april permission to reproduce and disseminate this material has been granted by to the educational resources information center (eric) u.s. department of education office of educational research and improvement e cational resources information center (eric) his document has been reproduced as ceived from the person or organization originating it. minor changes have been made to improve reproduction quality. points of view or opinions stated in this document do not necessarily represent official oeri position or policy. paper presented at the annual meeting of the american educational research association. new orleans, la, april . best copy mailable abstract: a large literature exists in which scientists describe their field as beautiful and the work they do as inspired and passionate. science teaching should strive to foster learning of substantive and powerful science ideas in ways that connect to the beauty inherent in those ideas. our conception of learning science, that of learning for aesthetic understanding, achieves this goal by building on a framework of aesthetic experiences proposed by dewey. this paper is an articulation of the major components of aesthetic understanding, pedagogy designed to foster it, and the results of a pilot study designed to investigate its effectiveness. statistical results suggest a positive effect from the pedagogy and, even more interesting, are the voices of students as they describe their experiences learning for aesthetic understanding. understanding is a lot like sex. it's got a practical purpose, but that's not why people do it normally. ...frank oppenheimer(as cited in cole, , pg. ) the world looks so different after learning science. for example, trees are made of air, primarily. when they are burned, they go back to air, and in the flaming heat is released the flaming heat of the sun which was bound in to convert the air into tree. [maid in the ash is the small remnant of the part which did not come from air, that came from the solid earth, instead. these are beautiful things, and the content of science is wonderfully full of them. they are very inspiring, and they can be used to inspire others. ...richard feynman (as cited in national academy of science, ) beauty and inspiration in science a suprisingly large literature exists on the role aesthetics, creativity, passion, beauty, and art play in the lives and learning of scientists (chandrasekhar, ; dawkins, ; dirac, ; mcallister, ; poincare, ; root-bernstein, , ; tauber, ; wechsler, ). scientists sometimes describe their work as beautiful and artful citing these qualities as the motivating forces that often drive their work. as poincare describes, "the scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful...intellectual beauty is what makes intelligence sure and strong" (pg. - ). an acute awareness of the beauty inherent in scientific ideas and scientific discovery necessarily draws us in to its study. to learn science from this perspective is best viewed as an integrated act, rather than solely cognitive or solely discursive. we believe this to be the most serious drawback of both conceptual (brown and clement, ; clement, ; clement, ; mccloskey, ; mccloskey, caramazza, and green, ; posner, strike, hewson, and gertzog, ; rosnick, ) and discursive (gallas, ; lemke, ; gregory, ) perspectives on understanding and find that a deweyan, aesthetic perspective allows us to blend cognitive and discursive ways-of-knowing with all important affective and artistic ways-of-knowing into a more unified, holistic, human understanding. science educators frequently look to the science discipline for guidance as to the important subject matter ideas, behaviors, and dispositions to guide teaching and learning. often, science within the discipline is characterized as highly analytic, logical, objective, and methodical. pedagogy that draws from this characterization of science frequently asks students to step back, to be critical observers of objects, events, and the world. however, some scientists portray science with quite an opposing personality - one that draws us in, begs our creativity, passions, and emotions. this portrayal of science can be described using dewey's epistemology in ways that break down false binaries such as objective vs. subjective, logic vs. intuition, thought vs. feeling, mind vs. heart, and think vs. feel. dewey's epistemology refuses to separate these into discrete, distinguishable acts. similarly, cherryholmes writes, "when we give up the text/context distinction [or any other binary in his argument], we deny ourselves the luxury of looking at the world in fragments (pg. , ). to think is to feel, and vice versa. a large literature exists to support this claim in science and science learning (see root-bernstein, for a good start). we believe the heart of a critique of conceptual and discourse-based understanding lay in their portrayal of science as something to be analyzed, stood back from, and acquired. from the perspective of aesthetic understanding, science learning is something to swept-up in, yielded to, and experienced. learning in this way joins cognition, affect, and action in productive and powerful ways. it is a more holistic in its substance and consequence. we draw from the work of scientists and philosophers of science to further support our claims and critique. when einstein wrote, "i am a little piece of nature" (in holton, , pgs. - ), his comment may not have seemed unusually illuminating. certainly we are all little pieces of nature, made of similar stuff, with origins in distant stars and supernovae, but these thoughts remove einstein's words from their intended meaning. root-bernstein elaborates, that which is true is what satisfies me after i have struggled with it, interrogated it, and pondered the meanings of its answers in light of my experience, my existence, myself. i become what i study, and when the i and it merge, understanding has been achieved (root-bernstein, pg. , ). in light of this, we see that einstein was implying a merger, a joining of the i and the it in an effort to understand. we are all little pieces of nature and we must work to recognize and draw on that connection in ways that assist our understanding. knowing in this way has been described as a synthetic process in which cognition, emotions, and actions merge; perception illuminated by multiple senses and sensations. this perceptual fusion is called synaesthesis by richards et al. ( ) and is described as "the simultaneous, harmonious experience of diverse sensory impressions from complex works of art resulting in a fusion of apparent opposites or unification of differences" (pg. ). synaesthetes, people who experience this quality of perception, often describe numbers as particular colors, temperatures as particular tastes, and sounds as particular images (see lemley, , for a more recent discussion). odin ( ) elaborates, synaesthesia represents a degree of unified sensibility so profound that the boundaries of the senses actually merge, and the multivariate sense qualities colors, sounds, flavors, scents, tactile and thermal sensations all seem to melt into a continuum of feeling (pgs. - ). many scientists have described similar multi-sensory experiences, similar to the way einstein described himself as "a little piece of nature," to include a joining of thought and feeling. root-bernstein expands on synaesthesia to something called synscientia. synscientia means literally, knowing in a synthetic way, being able to conceive of objects or ideas interchangeably or concurrently in visual, verbal, mathematical, kinesthetic, or musical ways. very simply stated, i have found no eminent scientist who simply solves mathematical equations or pours chemicals into test tubes and analyzes the results or catalogues chromosomal abnormalities. scientists, or at least scientists who are worth their salt, feel what the system they are studying does. they transform the equations into images; they sense the interactions of the individual atoms; they even claim to know the desires and propensities of the genes ( , pg. ). root-bernstein proceeds with multiple examples of synscientia from scientists such as jane goodall, dian fossey, ernst mach, and barbara mcclintock. similarly, we recall temple grandin, autistic animal scientist at colorado state university. as described by oliver sacks in an anthropologist on mars ( ), grandin has a unique ability to put herself in the position of her animals, "i visualize the animal entering the chute, from different angles, different distances, zooming in or wide angle, even from a helicopter view - or i turn myself into an animal, and feel what it would feel entering the chute." so impressed with grandin, sacks continues, "...her sense of animals' moods and feelings is so strong that these almost take possession of her, overwhelm her at times. she feels she can have sympathy for what is physical or physiological for an animal's pain or terror..." (pg. ). grandin's ability to think and feel in multiple ways, her synscientific abilities, helped her to become one of the world's most highly regarded animal scientists, despite adult autism. synaesthesia and synscientia are certainly extreme examples but we can learn important lessons from these ideas. a powerful, scientific understanding (similar to an artistic understanding) puts one in close personal contact with ideas that can (and should) change the way we think, feel, and act. again, root- bernstein writes, "inherent in the recognition that scientific creativity relies upon the same aesthetic tools of thinking as the arts is that the arts can be the source of skills and insights that science needs to progress" ( , pg. ). although root- bernstein is referring to scientists and scientific progress within the discipline, we believe we should apply the same standards and suggestions for the teaching and learning of science in our schools. teachers should strive for similar but developmentally appropriate experiences with beauty and aesthetic appreciation of science ideas. if we are to truly educate our children we develop both the scientist and the artist within them. as we have seen, science is not only the process of stepping back and analyzing the world with cold logic and rigorous methods. science is also stepping forward in an attempt to 'get inside' of objects, events, and ideas; it involves a surrendering to experience (wong et al, ). one is incomplete without the other. as we believe science is most commonly portrayed as the former, we focus here on the latter and suggest educating the artist within young scientists. it is common for the science education community to suggest doing science as those within the discipline do, to be more faithful to the discipline of science, and to do and learn as scientists do (see harding and hare, for one recent discussion). if we really believe this then we should listen to what the creative process of science suggests and work to foster powerful, transformative, forward-looking, aesthetic, synscientific experiences within students. like oppenheimer in the quote that leads this paper, we believe understanding is not most commonly driven by practical or instrumental purposes. the desire for understanding is driven by something more human. it is our nature to seek connections connections to others, to the earth, and to important ideas. this sense of connectedness is not only at the level of individual cognition; it comes from a desire to know with one's heart and mind, emotions and cognitions, imagination and reason. understanding is a lot like sex. we do it to feel connected in ways that tell us we are human. as feynman suggests in the quote that follows oppenheimer, we strive to understand for aesthetic reasons. drawing from dewey's naturalized epistemology and philosophy of aesthetics, we believe that teaching and learning should be guided by the having of meaningful experiences, connecting ourselves to the world and powerful science ideas through artistic metaphor, ending in the state we've defined as aesthetic understanding. on aesthetic understanding illustrated nicely by feynman and others above, an aesthetic understanding is a rich network of conceptual knowledge combined with a deep appreciation for the beauty and power of ideas that literally transform one's experiences and perceptions of the world. increasingly, philosophers and educators argue that the arts and aesthetics have lessons to teach us about ourselves and our world, affect and imagination, passion and cognition (dewey, ; eisner, ; garrison, ; greene, ; jackson, ). we believe we can teach science in ways that borrow from aesthetic and artistic ways-of- knowing, engaging more students with the beauty, power, and value of science ideas. aesthetic understanding accomplishes this in three ways. aesthetic understanding is transformative. feynman's quote illustrates the transformative nature of aesthetic understanding as he "sees" the event of combustion in a different and beautiful way. in an astronomy unit, a student named robert explained, "i never realized everything was moving the earth, the sun, the moon, the stars everything is moving and it blows me away!" realizing he would never view the night sky the same again, robert added, "i never thought i'd become the kind of person who talked about and thought about such deep things." aesthetic understanding literally transforms who we are and how we see the world. aesthetic understanding is unifying. part of aesthetic understanding is developing coherence of parts, pieces, ideas, and concepts. for example, as one learns about individual elements of the periodic table, the entire table is better understood as a series of relationships and continuities. individual elements and relationships between elements merge in a unified and dramatic way, disclosing secrets, and allowing one to see the beauty inherent in the structure of chemistry. aesthetic understanding is compelling and dramatic. aesthetic understanding draws students into the world through intellectual interactions and explorations. it is common for these students to think about science ideas outside class, to search for examples and illustrations of ideas, and to tell others about what they've learned, relishing in the excitement and engagement of looking at the world with wider eyes. aesthetic understanding teaches content and it demonstrates an empowering way of perceiving and interpreting the world through science ideas. in the eloquent words of maxine greene ( ), students become more "wide- awake" to the world, appreciating beauty and structure in new ways. this is what aesthetic understanding adds beyond more traditional learning. how can one teach in ways that foster aesthetic understanding? pedagogy has been developed across a period of two years designed to facilitate a high degree of aesthetic understanding in elementary science students. as compared to the students and school in which this research was conducted, the pedagogy was developed and refined in a similarly urban, midwest elementary school with similarly diverse students. the teacher plays a unique role in teaching for aesthetic understanding. a useful metaphor for describing her job is to imagine her as an artist in a studio trying to shape curricular ideas and experiences for children in artistically pleasing and aesthetic ways. her job is to position students in the path of potentially unfolding aesthetic experiences. she does this first by structuring the curriculum in ways that assist or support transformative, aesthetic experiences. pugh ( ) describes this process as "artistically crafting" more traditional pedagogy into pedagogy to foster aesthetic understanding. briefly, we will describe main guidelines to artistically craft pedagogy followed by an extensive example of pedagogy to foster aesthetic understanding. crafting content: too often science is portrayed as content to be known rather than experiences to be relished. most science ideas were at one time exciting and powerful but have since come to be embodied in bold-faced words, with exceedingly clean and tidy definitions. take, for example, the idea of a heliocentric solar system. long ago this was a frightening, provocative, even terrifying idea one that forced students to think about the world and their place in it, very differently. today, however, the notion of a heliocentrism is taken for granted as something always known or understood. heliocentrism has lost its artistic power to shape our understanding in profound ways. the first step in teaching for aesthetic understanding is to re-capture or re-animate existing content into the artful and compelling ideas they are (or were at one time). crafting dispositions: while teaching for aesthetic understanding a teacher should ask students to be more imaginative and creative as they wonder about the potential of ideas. students should ask more, "what if..." style questions such as, "what if this rock could talk? what story could it tell of its travels?" students should be pushed to imaginatively explore the power of science ideas in ways similar to einstein's famous thought experiments. investigating the potential of ideas to transform takes time and opportunities. teachers must provide rich opportunities to explore, wonder, and begin to make sense of science ideas and their power to alter our perceptions of the world. emphasis on the artistic expansion of perception: our brains are amazing. with just a quick opening and closing of our eyes, one can gather a great deal of information about your surroundings color of the room, approximate number of people in it, something of the objects in the room. this ability to rapidly recognize and interpret our surroundings is vital to our existence. however, it also serves to blur perception. too much of what we see in the world is generalized and simplified. we often fail to look closely and carefully at our world. "re-seeing" is an attempt to focus our perception on the nuance and detail of the world. re-seeing requires that we look carefully when we might be tempted to assume we see everything. re-seeing is also a disposition that causes us to ask questions of what we perceive such as, "what's really going on here? why do things look the way they do?" and "what kinds of things do i need to know more about to really re-see this?" during the course of an astronomy unit, a student named edie exclaimed excitedly, "i did some re-seeing last night!" while getting into her mother's car, she noticed the moon and it's features. "i could actually see different shapes and things on the moon and you could tell that it was just a shadow that made it look like a fingernail." for probably the first time in her life, edie looked carefully at the moon and wondered why it looked like it did she "re-saw" the moon. re-seeing, with its emphasis on dewey-like perceptual metaphors, can be used as a central activity in teaching for aesthetic understanding. model aesthetic understanding: recall the feynman quote that begins this proposal in which he artfully describes the process of combustion. feynman exemplifies what it means to have a well-developed sense of aesthetic understanding of the process of combustion and, likewise, teachers must model ways-of-knowing that incorporate a variety of avenues for engagement, specifically inspiration and appreciation for the beauty of science ideas. more than just modeling this artistic connection, teachers must model their appreciation and value for the transformative power of science ideas. scaffold efficacy and identity beliefs: as students engage with science through this unique portrayal, they will inevitably experience a wide range of emotions and dispositions. teachers must capitalize on and scaffold the development of dispositions that indicate an emerging sense of science identity and efficacy beliefs regarding students' ability to appreciate and come to a rich level of aesthetic understanding. aesthetic understanding forces us to see and think about the world in very unusual ways and initial attempts in this regard must be received in a nurturing way. given the theoretical framework of teaching for aesthetic understanding and the pedagogical strategies outlined above, the following research questions were asked: . does teaching for aesthetic understanding work, or, do the pedagogical strategies outlined previously help students to develop scientific understandings that include the qualities described by the theory of aesthetic understanding? . how will students talk about their experiences learning science for aesthetic understanding? the research in an effort to answer these very exploratory questions, all fourth grade classes in a midwest, urban elementary school were targeted. children in two classrooms participated including girls and boys. children in this area come from predominately lower and lower middle class neighborhoods, almost even distributed between african american and caucasian students. the instructional program in both classes was intentionally reorganized from learning that was for conceptual understanding to learning that was designed for the goal of aesthetic understanding.' three units were covered across ten weeks of instruction. both prior to, and at the conclusion of all science instruction, a measure of aesthetic understanding was administered. the instrument included a vignette about a girl named sarah who learned about friction and found it to be powerful and important to her. although her learning is not labeled as an example of aesthetic understanding, it was designed to be a clear example of just that. students in both classes were read this vignette and then asked to respond to a series of eight questions that investigated the degree to which they have had experiences similar to the one described in the story. each question on the measure relates to some element of aesthetic understanding such as a perceived transformation of person and world, learning that brings unification or coherence to aspects of the world or science, and something of the compelling and dramatic nature of learning in this way. the measure is appended. because it was not the intent of this research to make comparisons against learning that is designed for conceptual understanding, we did not find a control population necessary. we were only interested in exploring the learning of these particular students as the goals of their science instruction were shifted. we can, however, draw general conclusions regarding prior student learning for conceptual understanding as this was the instructional goal prior to the study. in fact, at the conclusion of each unit, students still responded to a traditional test of conceptual understanding. although we make brief references to these scores, comparisons between aesthetic understanding and conceptual understanding was not the focus of this research. student responses were recorded on a -point likert-type scale ( = no, - = increasing gradations of yes, where is "yes, somewhat like me" and is "yes, definitely a lot like me.") and the following results were obtained. table : responses to vignette questionnaire question mean response t-test . have you ever had a powerful learning experience in science like the one sarah had (student in vignette)? if so, how similar was it? . have you ever learned something in science and then seen the world differently because of it? if so, how different did you see the world? . have you ever learned something in science that made you think differently about yourself? if so, how differently did it make you feel? . have you ever learned something in science and then thought about it all the time outside of class? if so, how often does something like this happen to you? . have you ever learned something in science and then told other people about it? if so, how often does something like this happen to you? . have you ever learned something in science class and then tried to see examples of it outside of class? if so, how often does this happen to you? pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . t-value = . -tail sig. = . t-value = . -tail sig. = . t-value = . -tail sig. =. ns t-value = . -tail sig. =. ns t-value = . -tail sig. =. ns t-value = . -tail sig. = . . have you ever learned about something in science class and then tried to learn more about it outside of class? if so, how often does this happen to you? . have you ever learned something in science class that really helped you to understand more about the world? if so, how often do you learn something like this? . total measure of aesthetic experience (sum of questions - ) st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . pretest = . st.dev. = . posttest = . st.dev. = . t-value = . -tail sig. = . t-value = . -tail sig. = . t-value = . -tail sig. =. although we did not specifically ask students if they 'saw beauty' in science ideas, the analytic framework of aesthetic understanding is grounded in the aesthetic theory of dewey and the having of aesthetic experiences; experiences in which the beauty of ideas is necessarily experienced. we felt anything more direct would be excessively leading. as with any self-report instrument we had concerns regarding the accuracy of student responses. as a check in this regard, students indicated on a scale from to how similar their typical experiences learning science are with the idealized one described in the vignette. the responses on the eight items were correlated with this self-rating and yielded a correlation of . . this gives us some measure of confidence in the reliability of student responses. these results show that, for the most part, students experienced clear, and in some cases, profound progress toward the three conditions of aesthetic understanding. the items that don't bear out as significant (items - ) all tend toward aesthetic understanding and are very near significance. there were no significant gender or ethnicity effects. this data suggests the pedagogical strategies seem to be effective at facilitating the kinds of experiences and aesthetic understanding that we had hoped it would. we now turn to three students and their descriptions of the aesthetic experiences they underwent (or not as in the case of james) as a result of aesthetic understanding. these vignettes are based on student interviews, student writing, and the teacher's instructional journal. these students were chosen because they represent common experiences among the students. all names are pseudonyms. the subject matter referred to in these case studies is rocks and minerals. rather than allow traditional concepts like the rock cycle and erosion and weathering guide the unit, the teacher employed a narrative lens allowing "the telling of rock stories" to be the goal of the unit. the idea was that rocks are keepers of interesting and exciting stories that give us clues to the earth's past and the local geology of the region. knowing a few simple geologic principles allows one to unlock these secrets and tell the story of the rock. in addition to re- focusing the content, the teacher also employed the pedagogical strategies outlined earlier. the vignettes come mainly from this geology unit in which telling rock stories was the goal. names of the students represented in the vignettes are, of course, pseudonyms. brieana bright and bubbly, brieana's learning typifies aesthetic understanding. "most people think rocks are...just junk. most people think rocks are all the same and not interesting. most people don't think about their stories." brieana described several occasions in which she had recently found a rock and wondered of its story (origin and cooling history, erosion and weathering history...). brieana's perception of rocks changed entirely until finally she explained, "i used to skip rocks down at the lake but now i can't bear to throw away all those stories!" rocks were no longer dull and ordinary. they had taken on new meaning, beauty and power as their secrets were revealed. individual rocks had been transformed into miniature history lessons dramatic and intensely evocative in their story. soon the power of her emerging aesthetic understanding (as related to rocks and simple geology) began to spill over into other areas. brieana stated, "i've been thinking about the number . where did it come from? a guy just didn't say, 'here's two.' i want to know about its story. it seems to be important two shoes make a pair, two ears, two hands, two arches at mcdonald's." rock stories and her aesthetic understanding soon evolved into a full-blown narrative perspective on the world. she was 'infected' by the power of story and found great aesthetic value in its consequences. "thinking about the stories of things is a great way to learn. it makes things more interesting and gets you to think about' stuff you've never thought of. i like it." story, as it began in application to rocks, had moved beyond her school experiences. brieana relished how her new-found narrative perspective on the world made the "familiar seem strange" and it captivated her deeply. brieana's case seems to suggest a connection between her developing aesthetic appreciation for the power of story and her developing sense of conceptual understanding of geology concepts. generally a good student in other subjects, brieana did not usually excel in science. however, in this geology unit brieana's emerging value for story compelled her to engage more deeply than she may have in the past. as a result, she scored % on her end of unit test of conceptual understanding; a full letter grade higher than her average science unit grade in the past. leo leo was slightly less successful than brieana in coming to a well- developed aesthetic understanding. previously quite unsuccessful in school both academically and socially (in fact, leo was expelled shortly after this research), leo found success in his ability to imagine the lives of rocks. leo had no trouble imagining himself as a molecule swimming in molten lava, trying to form crystals. it appeared as though he was just being silly as he "swam" around the room with his eyes shut exclaiming, "it's hard to swim in molten lava. if it cools too soon, i won't form crystals!" his learning is aesthetic in the degree to which emotion and cognition are bound up in these experiential moments. his ability to relate to subject matter ideas in ways that join cognition and affect facilitated his ability to develop an aesthetic understanding and aesthetic value. in addition, leo seemed to experience content in ways that allowed him to more clearly see himself and his identity in relation to subject matter ideas. this narrowing of the gap between self and science proved very powerful for leo. in a post-instruction interview, leo told rock-related stories in just over minutes. the entire time he held a rock in his hand, touched it to his face, and even rubbed it on his lips. through rocks and their stories, leo was able to connect to academics and his teacher in ways he had not previously. although leo just barely passed the post- test of conceptual understanding ( %, class average %), for the first time in his experiences as a science learner (perhaps as a learner at all), leo came alive with energy, interest, and action for learning. perhaps if given the opportunity to develop his faculties for acquiring aesthetic understanding, leo would grow to be a more academically successful and engaged student. leo represents a situation in which conceptual understanding and aesthetic understanding do not seem to be linked. we argue, however, that given the opportunity to learn science more frequently for aesthetic understanding, leo's would develop his skills at appreciating beauty and the motivational ramifications of these appreciative experiences would begin to bootstrap his emergent conceptual understanding. james james was an outstanding student who always read the directions, raised his hand when he had a question, and wrote in complete sentences. james was generally considered to be one of the brightest students in class and always willing to work hard to perform well on assignments. perhaps his high expectations and almost rigid ideas about how to 'do school' left james unable to "undergo" (dewey, ) aesthetic experiences, failing to allow them to work their transformative power. james simply did not come to value story as an important idea, he explained, "thinking about rock stories is interesting but i don't really think about rocks differently than i did before. i am sort of interested in rocks and sort of not. i used to look for good rocks to skip but that's about it. i still do that. now, i can say what kind of rock it is and even tell my parents about it if they want but mostly i just skip them." although james was successful in traditional ways (attained one of the highest scores on the end-of-unit test), how successful was he in having a truly educative learning experience not successful at all from the perspective of aesthetic understanding. again, james represents a case in which conceptual understanding and aesthetic understanding are not linked. unlike the scientists described at the beginning of this paper james acquired a strong conceptual understanding but simply failed to come to an appreciation for the beauty of science ideas. unfortunately, we believe james represents a common endstate in science learning. students who do develop a strong conceptual understanding infrequently develop their aesthetic senses and values as well. this can be attributed to the minute amount of time and energy put into these goals. discussion and conclusions brieana, leo, and james represent decreasing degrees of successful aesthetic understanding. their words speak clearly in this regard. they each felt varying degrees of the power of aesthetic experience and its potential to offer them transformed views of themselves and the world, more unified visions of the world, scientific concepts, and relationships, and more compelling ways of thinking about the world. what we find to be most significant in this research is not that we were able to foster aesthetic understanding to a statistically significant degree but how students experienced their learning and subsequent value for science ideas. in fact, in post-instruction interviews % of the students ( of ) indicated that the realization that rocks and all things have stories that we can reconstruct is a valuable and enriching way to think about the world. as represented by both brieana and leo, it is this value which teachers should strive to foster and learners should strive to feel for subject matter ideas. it is this aesthetic value that helps us to live more richly fulfilling lives. additionally, we believe teaching for aesthetic understanding works to collapse or merge in-school and out-of-school learning experiences in ways that blur the lines between formal and informal learning. an important quality of aesthetic understanding is the way new ideas move students out into the world, beyond the walls of the classroom to enriched experiences and interactions with the world. the results of this 'moving out' is apparent in brieana's and leo's descriptions of their experiences. we believe the goal of school and education should be more than to get a good job, to educate responsible citizens, or to prepare children to compete in a global society. we believe education should serve to foster aesthetic experiences and facilitate aesthetic and artistic ways of viewing, acting, and living in the world. we believe the goal of education should be to foster aesthetic understanding of important and compelling ideas in this case, science ideas. the pedagogical strategies we employed seemed to facilitate these kinds of experiences and the valuing of ideas that emerged seemed connected to reasons or explanations beyond the purely instrumental. what teacher has not cringed as students ask 'when are we ever going to use this?' or 'why do we have to learn this?' what a powerful response if teachers were to reply 'you learn this because we hope it will bring more pleasure, beauty, and inspiration to your life. we hope you find value in its power to transform your mind, heart, and world.' we believe learning of this nature, and the motivation that follows from it, are intense, dramatic, and aesthetically pleasing. we believe teaching and learning for aesthetic understanding represents science education at its very best. appendix: measure of aesthetic understanding listen carefully as i read this story to you about a student who learned important things in science class. in science class, sarah learned about friction. she learned that when objects move there is always some friction where the two objects rub together. she watched carefully as her teacher pushed a book across the table and described the friction that tried to slow the book down. she felt as if she could actually see the friction between the table and the book. she learned that friction is everywhere and wanted to learn even more about it. sarah took her science book home and read about friction to her mother. she even looked in her older sister's science book for more information about friction. soon sarah could tell the difference between sliding friction and rolling friction, she learned that friction causes heat just like when she rubs her hands together for warmth. sarah began to see friction everywhere she looked. her baby brother slipped and fell down in the kitchen and sarah knew he fell because there wasn't enough friction between his feet and the floor. she realized that when people go skiing or ice-skating they try to reduce the friction so they can go faster. she also began to understand why some trucks have big knobby tires to provide more friction in the mud! sarah thought about friction a lot. she even thought about herself differently as just another object trying to create or reduce friction to move around in the world. mark the answers on your paper that best describe your reactions to the story. remember, the story is just an example. you could have an experience like sarah with lots of different science ideas. ) have you ever had an experience in science class like sarah? (circle one) yes no if yes, what science ideas or concepts were you studying at the time? if yes, how similar was your experience to sarah's? (circle one) pretty much the mostly the a little the same same same just barely the same ) sarah saw the world very differently after she learned about friction. have you ever learned about something in science and then seen the world differently because of it? (circle one) yes no if yes, how differently did you see the world? (circle one) totally quite a bit a little only a tiny bit differently differently differently differently ) learning about friction even made sarah think differently about herself. have you ever learned something in science that made you think differently about yourself? (circle one) yes no if yes, how differently did it make you think about yourself? (circle one) totally quite a bit a little only a tiny bit differently differently differently differently ) have you ever learned about something in science class and then thought about it all the time like sarah did? (circle one) yes no if yes, how often did you think about what you learned? several times a once a day day only a few times just once ) have you ever learned about something in science and then told other people about it like sarah did? (circle one) yes no if yes, how often do you learn something in science and then tell other people about it like sarah did? (circle one) almost once or twice a once or twice a about once or everyday week month twice a year ) have you ever learned about something in science and then tried to see examples of it outside of class like sarah did? (circle one) yes no if yes, how often do you try to see examples of things you learned in science outside of class? (circle one) everyday a couple times a couples times once or twice per week per month all year ) have you ever learned about something in science and then tried to learn more about it outside of class like sarah did? (circle one) yes no if yes, how often does this happen to you? everyday a couple times a couples times once or twice per week per month all year ) have you ever learned about something in science that really helped you to understand a whole bunch of other things like friction did for sarah? (circle one) yes no if yes, how often does something like this happen to you? (circle one) everyday a couple times a couples times once or twice per week per month all year ) think about how you generally learn things in science class. typically, how similar is your learning like sarah when she learned about friction? not similar at all very similar references author ( ). the elementary school journal. brown, d.e. and clement, j. 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( ). the opposite of control: a deweyan perspective on intrinsic motivation in "after " technology programs. computers in human behavior, ( ), - . footnotes 'conceptual understanding and discursive understanding are two frameworks within the teaching for understanding movement. each of these puts something different at center stage; mental models for one and linguistic competence for the other. aesthetic understanding is similar to these two in that we argue for ours as a model of understanding. however, an important difference is that aesthetic understanding places an appreciation for the beauty of science ideas and deweyan aesthetic experiences at center stage. for a more thorough analysis and critique of the conceptual and discursive frameworks from the perspective of aesthetic understanding see author ( ). we do not intentionally imply that these two kinds of understanding are exclusive of one another. on the contrary, a significant quality of aesthetic understanding is conceptual understanding. in fact, treatment group (class taught for aesthetic understanding) average end-of-unit test scores of conceptual understanding remained consistent before, during, and after treatment. this suggests teaching for aesthetic understanding has no cost in terms of conceptual understanding. we expect future research, designed to investigate this specifically, will demonstrate that, in fact, conceptual understanding is actually enhanced when goals are shifted to teaching for aesthetic understanding. u.s. department of education office of educational research and improvement (oeri) national library of education (nle) educational resources information center (eric) reproduction release (specific document) i. document identification: ( r-is e ic educational resources information center aera title: ar e reel gtit -ire ce.a. - 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. toll free: - fax: - e-mall: ericfacelneted.gov www: http://erictacillty.org eff- (rev. / ) journal of social, humanities and administrative sciences open access refereed e-journal & refereed & indexed issn - article arrival date: . . published date: . . vol / issue / pp: - the beauty of novel “shakan-sheri” bibigul mynbaikyzy sultanova kazakh state women’s teacher training university, , aiteke bistr., almaty, kazakhstan shodankyzy toiganbekova kazakh national university of a name of al-farabi, almaty kazakhstan gulfayrus kazybayevna ibrayeva kazakh national academy of arts named after t. k.zhurgenova (boarding-school and college) almaty, kazakhstan gulmira kalibayevna abdirasilova candidate’s (ph.d.) degree in philological sciences, an academic title of associate professor of linguistics kazakh state women’s teacher training university, , str. aiteke bi, almaty, kazakhstan abstract mukhtar magauin is a kazakh writer and publicist. he was born in the district of chubar-tau in semey region (now east kazakhstan province) of kazakhstan on february . he graduated at the kazakh state university ( ) and the doctorate ( ) there. he was head of the literary criticism department at the “kazakh literature” newspaper in almaty. he publishes several scholarly articles and books and novels. when he was mentioned by the soviet study experts in the west in the book edited by edward allworth as one of the nationalist kazakh writers ( ), the local communist rulers put his name to the “black list”. most of his renowned uncensored novels were published only after the collapse of the soviet union. he published the novels “the yellow kazakh” ( ), “abc of the kazakh history” ( ), “dreams of kypchaks” ( ), “the half” ( ), shakan-sheri” ( ) etc. in , he became the winner of the international prize for the turkic speaking writers and culture workers and he received the prize from suleiman demirel, the turkish president at that time. he is also a holder of the title of the people’s writer of kazakhstan. magauin translated several short stories and novels of the prominent foreign writers (william somerset maugham, henry rider haggard, etc.) into kazakh. nowadays he lives in prague, the czech republic. mukhtar magauin - one of the most talented writers, whose work has attracted special attention from literary critics. creativity mukhtar magauin characterized by a rich palette of genre and style, is the subject of a detailed analysis of literary theorists. m.magauin's creativity of the soviet time more or is less investigated. m.magauin’s novel “shakan-sheri” the most interesting products and from the point of view of subject movement, and from the point of view of construction of products, style have appeared since . in this connection in the given work the new novel of the writer is considered, and products of the soviet time are anew reinterpreted. in connection with that during independence republic of kazakhstan there was a necessity rereading and reconsiderations of the literature of the soviet period, and also research of a modern condition of the literature from new positions. key words: image, poetry, lyrics, genre, style, genre and style palette, analyzes, literary critic, a cycle of poems. the great, truely, national writer of kazakhstan mukhtar magauin was born in in chubartau district of the semey region. in he has graduated from the philological faculty of the kazakh state university of kirov, and in - a postgraduate study. m. magauin has begun to write since . in the beginning, he becomes widely known for his interesting researches on history of medieval kazakh poetry. only later he released several collections of stories: “kobyz saryny”, “kazakh akyn-zhyraulary” - monograph ; “kok munar” – ; “bir http://college.kaznai.kz/en/ https://en.wikipedia.org/w/index.php?title=chubar-tau&action=edit&redlink= https://en.wikipedia.org/wiki/east_kazakhstan_province https://en.wikipedia.org/wiki/east_kazakhstan_province https://en.wikipedia.org/wiki/kazakhstan https://en.wikipedia.org/wiki/soviet_union https://en.wikipedia.org/wiki/kazakhs https://en.wikipedia.org/wiki/communist https://en.wikipedia.org/wiki/turkic_languages https://en.wikipedia.org/wiki/demirel https://en.wikipedia.org/wiki/turkey https://en.wikipedia.org/wiki/president https://en.wikipedia.org/wiki/w._somerset_maugham https://en.wikipedia.org/wiki/h._rider_haggard https://en.wikipedia.org/wiki/h._rider_haggard https://en.wikipedia.org/wiki/prague https://en.wikipedia.org/wiki/czech_republic refereed & index & open access journal journalofsocial.com august journal of social, humanities and administrative sciences ( ): - atanyn balalary” - novels and stories ; “kok kepter” - novels and stories ; “alasapyran” (“distemper”) novel - film series - ; “shakan sheri” – ; “gasyrlar bederi” – ; “men” novel - film series; “gaukhar” – ; “taska zhazylgan kolzhazbalar” – , “shyngys khannyn sharapaty” – ; “on ush tomdyk shygarmalar zhinagy” - . these collections reflect the post-war peaceful life in city and village, the modern life of the intelligence and students. a novel - film series "alasapyran" ("distemper ") (book -i - , nd - , in russian - , ) reflects the historical relationship between kazakhstan and russia, the kazakh-russian diplomatic relations in late hҮІ - hҮІІ the beginning of the century. m.magauin is known about fifty years as a scholar, literary critic, historian and translator among literary circles and readers. m.magauin not only a great writer, but also a great translator. m.magauin - author of literary translation into kazakh language collection of selected s. maugham short stories ( ), the play "the kremlin chimes" i.pogodina, d.haggardta novel "king solomon's mines" ( ). m.magauin from the beginning of his career has his own importance, importance in the literature. its different from other styles of works. the high artistic level, subtle psychological analysis, deep philosophical thought, figurative language distinguishes his work. based on historical documents writer recreated a wide panorama of artistic life of the kazakh steppe and russia late xvi and early xvii centuries. from the first steps in literature mukhtar magauin proved us that he is able to use the enormous wealth of the native language, its flexibility, with rare, capacious, and at the same time gentle and radiant colors as well as shades. magauin is a master of plot construction works. he has lack of "reception" forcible introduction of the text superfluous plot conflicts. if we consider separately each human character, they are all in some way are familiar and unfamiliar at the same time. all works of m.magauin fully meet the requirements and demands of time. m. magauin with his weighty books answers to modern problems. feels that he explored deeply to the end a selected topic. amazing to learn how many archives "dug", visited cities the author of "shakhan-sherі" to create the novel. yes, muhtar magauin undoubtedly a huge talent. m.magauin’s prose is expensive and close to every reader and kazakh nature paintings embodied in it with tangible clarity, with the utmost melody and melodiousness. mukhtarmagauin came to the kazakh literature in the sixties of the twentieth century - the khrushchev "thaw", as it was at this time in the literature comes a new galaxy, a new generation - the young people, uncompromising, well-educated and have not looked up from his folk roots finally, how it will happen later in the period of general mankurt. m.magauin's creativity of the soviet time more or is less investigated. m.magauin’s novel “shakan- sheri” the most interesting products and from the point of view of subject movement, and from the point of view of construction of products, style have appeared since . in this connection in the given work the new novel of the writer is considered, and products of the soviet time are anew reinterpreted. in connection with that during independence republic of kazakhstan there was a necessity rereading and reconsiderations of the literature of the soviet period, and also research of a modern condition of the literature from new positions. the novel of mukhtarmagauin attracts rigorous, detailed knowledge is not so much the history of the kazakh people, many details of ethnographic way of his life. this includes knowledge of folk crafts, crafts, hunting, veterinary, breeding and birds of prey, hunting dogs, racehorses. this includes music, art song. even this simple transfer of knowledge of the writer can conclude that the basis of the author's conception of the world and man is the idea of knowledge. hunting was counted as an art, from old time it was main topic of literature. in this case, malik gabdullin, who did a huge works on kazakh literature once said: “hunting have been a profession mailto:journalofsocial.com refereed & index & open access journal journalofsocial.com august journal of social, humanities and administrative sciences ( ): - from long time in kazakh nation and as well as complex topic in kazakh literature. about hunting we can find out many stories, tales, epithets, metaphors in literature. in literature, when people image heroes, they talk how heroes were strong, powerful. later on, in aitys, every single poet compares himself to birds of prey, eagle”. in truth, despite from stories, tales in kazakh literature about hunting, we know heritages which are “ogyznama”, “korkyt epos” and many creations of mostly writers of kazakh nation. lately, one of the product about hunting that become popular in world literature not only in kazakh was novel “shakan-sheri”. in the novel “shakan-sheri” which written by great writer of kazakh literature, describes by character shakan the cultures of kazakh nation that kept until soviet union from long times. the novel discusses the problems of life like loneliness and person heartbreaks. «Қоңыр түндік ауыр ысырылып, əрең ашылғанда жез құрсаулы қара шаңырақтан ұйыған сүттей қою жарықпен қоса ақтарыла төгілген салқын, таза ауа жиһазы шамалы, жасауы шағын, бірақ кең, əрі еңселі төрт қанат киіз үй ішіне серпінді леп əкелген. Аязды, тымық таң. Бозғылт- сары аспан шексіз биік, кіршіксіз таза көрінеді. ✓ Шашадан қар жауыпты, - деді киіз есікті серпе ашып, сырттан құшағын толтыра қамыс сүйрей кірген Ажар. ✓ Жер-дүние аппақ» деген үзіндіден қамыс арасындағы жайбарақат өмір кешіп жатқан қыс мезгіліндегі аязды тымық таңды қарсы алған жалғыз үй иелері Шақан, Ажар баласы Сəлменді суреттейді. «Жер-дүние аппақ» деген сөйлем арқылы автор таңдағы жауған қармен бірге аталған үшеуінің де қаннен қаперсіздігін бейнелесе керек. Баласы Сəлменнің қан сонарға шығамыз деп қуануы, «Қандай жақсы!.. Қоқаңдаған, дікіңдеген ешкім жоқ. Тып-тыныш. Дұрыс болды, өңшең шуылдақтан бөліне көшкенім. Рахат. Иен қамыс, кең дала...» деп автор айнала қоршаған ортадан, туған-туыстан ауылын алысқа көшіріп алған, жалғыздықты таңдап, тағдыр- талайының қандай боларынан еш болжамы жоқ Шақанның аузына сөз сала бейнелейді. by comparing history of nation and events that happening in these days, the writer tried to describe about his native land, the environment that he grow up. the novel “shakan-sheri” by muhtarmagauin is special creation that describes human psychology. based from that, we can see that writer achieved a good result on beautiful describing in most situations. particularly, “shakan-sheri” has different level on artistry of it is content. in the novel beautifully describes how strong hunter shakan had a fight with angry tiger that attempted to commit to people. the relatives, after being victims of tiger, in shakan appeared a revenge to tiger, so shakan’s boldness and bravery were expanded chapters of novel. the novel describes comparison of glibness of hero with severe tiger. in general, in most creations about animals, we can see brave nature that belongs to people, especially individual nature in kazakh people. in the novel "shakan-sheri" artistic language of m.magauin has bright ornament and imagery. philosophic, seeking thoughts determine the presence of his literary personality. he is a master craftsman shaped feed their own thoughts, desire to give different living reality any picture. this is perhaps largely contributes to the skillful combination of magic phrases, phrases of the national language with many turns of speech artistic language, the ability to convincingly convey thought and word. the excellent combination of thought and word is the writer's work: proposals harmonious, clear, easy to understand, penetration, do not leave indifferent and awaken consciousness. m.magauin beautifully described the feeling of shakan when he saw first time the tiger, who lately cleaned ile, shelek, charynconion, and all zhetisu from angry, brave tigers. truly. special character trait is confidently. «Жалт бұрылған Шақанды қақ маңдайдан жасын ұрған. Маңдайдан ұрған жасын өне бойын көктей тесіп өткен. Төбе шашын үйтіп, қолқа жүрегін суырып, іші-бауырын талқандап, қара табанға темір қазық болып қағылған. Айқайлауға даусы шықпады, ұмтылуға, əлденендей қимыл жасауға аяқ, қолы ырық бермеді, Дем тартуға да дəрмені жетпей, mailto:journalofsocial.com refereed & index & open access journal journalofsocial.com august journal of social, humanities and administrative sciences ( ): - бақырайып қатқан да қалған. Есіктен тайдай сары тарғыл мысық сұғынып тұр екен. «Жолбарыс!..» [ , б.]. (“when shakan saw tiger first time, he even could not breathe. what he saw was a big yellow cat that coming into house and at that moment shakan could not move at all. “tiger!..” [ , page ].) the writer did not show shakan’s only heroism, also writer covered hero’s cowardice, weakness. worldly wisdom is not easy. in novel, written in very simple way how the men could fight back against twist of fate. we can see how writer tried to show each detail of the novel in such a good way. there are few characters only in novel, but it has very rich content with its interesting stories. there is vexation in fearless shakan who saw twist of fate. the distinguishing feature of talent mukhtarmagauin is not only deeply desire to know the history of his people, but truthfully be reflected in literary works. in the historical, artistic works of the writer plays a unique flavor of a particular historical period, people's lives, their customs and rituals, dreams and aspirations. m.magauin products which are written about past and present of kazakh people need to give a realistic assessment. m.magauin's creativity represents the significant contribution to the kazakh literature here already during more than forty years. the novel by the writer "shakan-sheri", published in and dedicated to the theme of hunting, heroism, intellectuals, moral and ethical issues of the time, striking his talented approach to topical theme, figurative and expressive language and accusatory motives against time. it would probably be unfair to consider novel "shakan-sheri" only to the topic of animals, since it touches on many issues such as morality, humanity. subjects creativity of m.magauin wide. in an effort to put into an art form the truth of life, the writer looks into deep social and spiritual aspects of life hero. writer, by the desire a deeper understanding of modern society from the perspective of world-knowledge by relations between society and human psychology penetrates into the inner world of the hero. literature - the spiritual world with limitless possibilities. to sculpt a comprehensive image of the hero, penetrate deeply into the spiritual manifestations of man, it is widely and artistic skill uses in his work all the possibilities: artistic techniques, methods, artistically-shaped tools. references . gabdullin m. kazakh khalkynynauyzadebieti. – almaty, . . magauin m. shakan-sheri. – almaty, atamura, . - . . nurgaliyev r.telagys. – almaty, zhazushy, . - . . maitanov b. lirism – stildikkubylys. – almaty, gylym, . –page . . piraliyeva g. zh. kazakhtyn korkem prozasyndagy psihologism tabigaty zhane onyn beineleu kuraly. –almaty, . . http://prstr.narod.ru/texts/num /arg .htm . http://www.azattyk.org/content/kazakhstan_culture_magauin/ .html . salkynbai a.b. slovo-obrazovanie v kazakhskomyazyke (in kazakh language). – almaty: kazakh university, . – p. . naraliyeva r.t., mukhanbekkyzy l., toiganvekova m. sh., sultanova b. m. modern methods of teaching kazakh as foreign language: search, innovation, quality, result // review of european studies. canada, vol. , no june . mailto:journalofsocial.com http://prstr.narod.ru/texts/num /arg .htm http://www.azattyk.org/content/kazakhstan_culture_magauin/ .html refereed & index & open access journal journalofsocial.com august journal of social, humanities and administrative sciences ( ): - . kasym b.k. slovo-obrazovanie: sementika. motivacia (in kazakh language). – almaty: alnu, . – p. . adilbayeva u. motivacianazvaniirastenii v kazakhskomyazyke (in kazakh language). cand. dis. in philology: . . . – almaty: kaznu named al-farabi, . – p. . akimisheva zh. motivacianazvaniiornamentov i prirodaznakov (lingvokulturnyiaspekt) (in kazakh language). cand. dis. in philology: . . . – almaty: kaznu named al-farabi, . – p. . osobennostiznacheniya i motivaciiproizdodnyhslov (semanticheskiisposob) (in kazakh language). cand. dis. in philology: . . . – almaty: kaznu named al-farabi, . – p. mailto:journalofsocial.com exhibition: making beauty: elpida hadzi-vasileva exhibition out of hours gut feeling making beauty: elpida hadzi-vasileva djanogly gallery, nottingham august – october making beauty is a site-specific installation at djanogly gallery in nottingham by the artist elpida hadzi-vasileva. she is a highly-respected artist from macedonia who has exhibited at the venice biennale representing her country, and the vatican. the exhibition contains reconfigurations of two previous major works of hadzi-vasileva; fragility, previously in the fabrica gallery in brighton, and haruspex, commissioned by the vatican in for display in its pavilion at the venice biennale. supported by wellcome trust funding, the artist collaborated with three digestive- disease specialist departments at university college hospital (london), the university of east anglia (norwich), and the university of nottingham, for the past year. she has taken inspiration from both her time spent in laboratory settings as well as direct conversations with patients. some of her exhibition pieces have even been made using models and techniques from the novel technology used in these medical research departments. on entering the exhibition one is immediately struck by the lace-like structure suspended from the ceiling. this work, entitled fragility (above) is composed of preserved caul fat painstakingly transformed into shimmering transparent sheets. these layers of hanging sheets with vein-like lace patterns transform the room into a cloud-like environment. at the end of this room, a spherical object is suspended from the ceiling and is titled haruspex. this piece conveys an eerie feeling with its tentacle-like structures draping down to the floor. following this grand entrance, the exhibition flows to the right with many individual smaller pieces of the artist’s work. what i found most interesting was the dome-shaped cow’s stomach playing gurgling bowel sounds (left); it is certainly a surreal experience listening to digestive sounds coming from what was once a living stomach! the gallery is accompanied by an insightful video interview introducing hadzi- vasileva; despite the the obvious intricate level of planning and preparation needed to create these works she intrigues us further by saying she ‘never knows what each piece is going to look like until it’s complete’. that i suppose is the beauty and curse of using natural products for art. the overarching concept throughout the exhibition is one of ‘life afer death’ and i believe the artist has fulfilled this ambition as she has created exactly that with these dead pieces of tissue now becoming lasting pieces of art. gurvinder sahota, clinical assistant professor in primary care, division of primary care, school of medicine, the university of nottingham, nottingham. e-mail: gurvinder.sahota@nottingham.ac.uk making beauty: elpida hadzi-vasileva is exhibiting at djanogly gallery, nottingham lakeside arts, nottingham, until october th . www.lakesidearts.org.uk/ doi: . /bjgp x british journal of general practice, october elpida hadzi-vasileva, rendition of self, , cow stomach, turned wood, audio, photo nick dunmur, courtesy elpida hadzi-vasileva. elpida hadzi-vasileva, fragility, ; caul fat, plastic, metal and wire; cm x cm x cm, fabrica gallery, brighton, england; photo: tom thistlethwaite, © the artist, courtesy the artist. rev_iss_web_jbg_ _ - .. review th wcgalp in beautiful vancouver r.j.c. cantet , o.f. christensen , m. p�erez-enciso & j.h.j. van der werf universidad de buenos aires, buenos aires, argentina aarhus university, aarhus, denmark icrea – centre for research in agrigenomics (csic-irta-uab-ub), barcelona, spain university of new england, armidale, nsw, australia correspondence asko m€aki-tanila, university of helsinki, finland e-mail: asko.maki-tanila@helsinki.fi received: august ; accepted: august the th world congress was inaugurated by orga- nizers filippo miglior and john pollak in vancouver at pm on sunday aug, preceded by a cocktail to warm up attendees’ epigenomes. we return to these congresses each time in higher numbers, now over participants. the arrangements were very good and the weather cherished us all week, including the boat trip out to open sea among the small hydroplanes whirling up and down around us on the water. the new technology was adopted in presenting the posters (of rather dated outlay though) and the talks could now be easily found by author names and also re-lis- tened to at the congress web site. it is not easy to itemise separate themes or avoid overlaps in review- ing the congress, where the sessions were thoroughly filled or hollowed by our extensive genome-wide studies. from sequence to presequence (miguel p�erez- enciso) in the review on leipzig’s wcgalp, i predicted that the vancouver meeting would be flooded by sequences: ‘at the next world congress, vancouver , complete genomes will be as popular as snp microarrays were at the leipzig venue’ (p�erez-enciso , j anim breed gen , ). i was wrong: van- couver wcgalp was overwhelmingly dominated by genomic selection (gs) issues with qtl – gwas stud- ies being never more popular in animal sciences. this is partly due to the clear practical focus of wcgalp but does not explain the whole variance among the communication dataset from the meeting. among the oral presentations, were on next- generation sequencing (ngs) data versus on genomic selection, on population genetics topics (selection footprint, variability), with gwas / qtl approaches and on systems biology (net- works, pathways). for the posters, the numbers were , , , , and , respectively. (these numbers are mainly based on reading the title of communications and are subjective to an extent). in any case, ngs talks were overrepresented sug- gesting that ngs was considered a hot topic while the animal ngs field has not exploded yet in its entirety. the same seems to be the case for systems biology. genomic selection was actually under rep- resented among oral contributions, possibly due to frequency dependent selection. for the observations above i have counted only genome wide sequence: rnaseq has become a popu- lar tool ( papers in the congress) than genomic ngs. the likely reasons are the lower costs and richer information. for example, e.g., rnaseq can be used not only to measure overall expression, but also allele specific expression (bill muir) or to refine the annota- tion. if one extrapolates the prospective avenues from the on-going human research, it can be expected epi- genome and metagenome to be quite popular targets in the near future. there were < papers on them in the meeting. most of the sequence data reported were on cattle, (over genomes). it seems that the most fruitful application of ngs was in detecting monogenic, dele- terious mutations. michel georges and richard spel- man used hardy–weinberg deviation to find lethal j. anim. breed. genet. issn - © blackwell verlag gmbh • j. anim. breed. genet. ( ) – doi: . /jbg. mutations affecting embryo development. they used some bull sequences ( x on average) with impu- tation for million animals. aur�elien capitan et al. at inra further isolated several causal mutations affecting rare syndromes using the bull genome data, which consists of highly influential bulls from breeds sequenced at on average of x. using the same data ben hayes found that with bayesr the accuracy of genomic selection accuracy is only some % higher than with dense marker set. imputation accuracy was % for minor allele frequency (maf) > . , and dropped dramatically for lower maf. the issue, of course, is that low maf variants are the most frequent ones in sequence data, and this could be one of the reasons why complete sequence did not help. after all, the subdued appearance of ngs data in the meeting is possibly caused by the difficulties in their analyses, which are much greater than antici- pated. such data require costly computer resources and are noisy for the scale needed in animal breeding. their analyses are also complicated due to limited sequencing depth (which introduces incertitude in snp calling). we have observed significant changes in the snp calling process when using two different ver- sions of the same software like samtools mpileup tool. jerry taylor confessed he had become a ngs addict, with bulls sequenced. so did i, but i am in a detoxifying treatment for the given reasons. as peni- tence, i devote now most of my time developing ana- lytical tools to make the most out of the data already available, and to optimize experimental designs before is too late. several communications (e.g., jerry taylor, vincent ducrocq, ben hayes, mike goddard) revolved around the utilization of the causal mutations in selection for complex traits, which seems a bit counterintuitive in the genomic selection paradigm. several decades of research and sequencing have proven how difficult this is, even if the causal mutations are present in your data. in wcgalp several authors, peter søren- sen and mike goddard, among others, recognized the importance of using biological information for predic- tion purposes. i fully agree but an accepted or mean- ingful way to do so remains to be elucidated. perhaps, one could start by recognizing that not all snps are born equal and introduce annotation in the model. tools like variant effect predictor in ensembl classify snps according to their expected degree of severity. when using sequence, this information can be readily taken into account in the priors. however, this is not relevant for genotyping arrays because most chip snps will be intergenic and likely neutral per se. in this paradigm, sequence data could make a difference. as you can guess, i do not dare doing any prediction for new zealand’s event, though. genomic selection matures (ole f. christensen) a very interesting symposium was about industry applications of gs. the session started from dairy cat- tle with esa m€antysaari’s historical perspective about the enormous impact of gs on the sector. for poultry, anna wolc presented the results from a multi-genera- tion gs and experiences about the gs implementa- tion in broilers and layers. in poultry the applications arrived later than in dairy cattle, primarily because of the prohibitive expenses of genotyping relative to the value of individual selection candidates. atlantic sal- mon is a very different species due to its much later domestication (only some ten generations ago). the present population is an admixture. another feature is the high fecundity both in males and females. jør- gen Ødegaard praised the high potential of gs in aquaculture and compared gs models in a two-trait context (lice resistance and fillet colour). there are clearly species specific issues in the gs applications. several presentations were about methodology for single-step genomic evaluation (ssgblup) using a hybrid relationship matrix with a good overview given by andres legarra. ismo strand�en presented an equivalent equation system for solving ssgblup with- out constructing and inverting the pedigree relation- ship matrix for genotyped animals. dorian garrick formulated ssgblup as a snp effect model. from a conceptual point of view it is very important to have the two equivalent formulations. zenting liu said that snp model allows excluding/including specific ani- mals in the training data. prediction across breeds was a topic with many pre- sentations and several groups are developing useful approaches. mario calus concluded that the predic- tions using information across breeds benefit from few closely related inidividuals while some individuals can deteriorate the predictions. shared large effect qtl’s improve the prediction across breeds (mahdi saatchi and dorian garrick), and they could be detected from imputed whole genome sequence (e.g. rasmus brøndum). in addition to the many sessions focusing by name on gs, there were presentations about genotyping and phenotyping strategies, and presentations where gs (or ssgblup) was not of primary interest but a natural part of the genetic evaluation. gs is now more mature and over the highest uncontrolled enthusi- asm. many of the challenges seen with pedigree-based © blackwell verlag gmbh • j. anim. breed. genet. ( ) – review genetic selection are still present. because the cost of genotyping is steadily coming down, there will be many more marker based evaluation programs. by the next wcgalp, i would expect to see many stu- dies where the main focus is not on gs but marker genotypes (or causal variants) are included in the genetic model. developments in quantitative genetics (julius h. j. van der werf) quantitative genetics is the foundation of much of the work in animal breeding. at the conference it was cov- ered by ‘breeding objectives, economics of selection schemes, and advances in selection theory’ but appeared in many other topics. the amazing genomic toolbox requires sound quantitative genetic theory to underpin models of analysis while challenging assump- tions. so genomics is causing a revolution similar to the one almost hundred years ago when ronald fisher and sewall wright proposed to use pedigree information to enhance genetic analysis of quantitative traits. the genome wide association studies give us a clue about the size and distribution of gene effects that control quantitative genetic variation, and further about gene by gene and gene by environmental inter- actions. the analyses with dense markers give infor- mation about the level of heterozygosity, or absence thereof, genetic diversity, and signatures of selection. molecular information also provides a tool to gain a greater insight about identity of descent at the level of a single locus, and from that we can derive coefficient of covariance for a range of genetic effects. for exam- ple, dominance variation can be estimated based on variation in genomic dominance relationships, and there is no longer a requirement of having full-sib families. theo meuwissen pointed out how the geno- mic prediction is contributed by information on pedi- gree, linkage and linkage disequilibrium. the relative importance depends on the true genetic model, with the linkage based approach being more important for large qtl effects. the veil of the underlying genetic model is slowly being lifted. some believe that the missing heritability problem is mainly due to non-additive genetic effects (e.g. zuk et al, pnas : ). however, asko m€aki-tanila and bill hill showed that epistatic effects rarely con- tribute much to the observed variation and taking them into account in either selection or gwas strate- gies is unlikely to have a large impact. these studies are good attempts to reconcile the top-down and bot- tom up approaches into quantitative genetic analysis, as suggested by eric lander at the international quantitative genetics symposium in edinburgh in . with sequence data we are able to detect more causal variants, but we are far from explaining the observed (additive) genetic variance with detected qtl effects and terabytes of data grinding should be passed to resolve for the explanation. the resurgence in the hunt for qtl is a logical next step in the geno- mic prediction models. hopefully, we can now make use of the lessons learned more than a decade ago. e.g. the selection on qtl is less optimal as the joint selection on qtl and polygenic background. this would be difficult to achieve if genomic selection was based on just a few qtl, suggested by jerry taylor for the use of sequence information. the plain phenotypic variation could be analysed by new genetic models, e.g. in the analysis of mater- nal and social effects, traits measured on trajectories and genotype by environment interactions. these could reveal nonlinear relationships between traits as shown by han mulder, and these effects could also be selected upon. epigenetic studies had not arrived in large numbers at the wcgalp in spite of being, for some years now, a hot topic in human genetic analy- ses. only eight studies looked at epigenetics, with sim- ple variance components or with gene expression or methylation patterns. i would expect that such studies will also become more common in animal genetics with interesting phenomena as an outcome. yaodong hu, guilherme rosa and daniel gianola showed that imprinting could lead to a significant reduction in the gwas heritability. it was good to see that optimal contribution selec- tion has now become part of the regular animal breeding toolbox. john woolliams considered cases where selection accuracy is equal to one and stated that ‘if accuracy does not approach one with huge numbers, then the community needs to completely overhaul the basis of its most cherished models for genetic evaluation’. we’ll have to see! in the symposium on breeding objectives some excellent insights were presented relevant to achiev- ing successful outcomes in animal improvement programmes. the debate continues because the assessment of utility that can vary between circum- stances and people. the area lacks a comprehensive theory, and if anything, we were made aware that the existing framework of (linear) selection index princi- ples are rarely found adequate when determining relative trait emphasis in multiple trait selection prac- tices (pieter knap; rob banks). jack dekkers made it clear that the way in which breeding objectives are achieved largely depends on the information available per trait, and e.g. genomic information may change © blackwell verlag gmbh • j. anim. breed. genet. ( ) – review the direction of genetic progress. it is somewhat ironic that the availability of genomic markers has sparked more interest in phenotyping, not less, with several sessions devoted to phenotyping for traits difficult to measure. at the end of the day, the genomic informa- tion just helps us to make better inferences but the phenotypic information remains the basis of genetic improvement. statistical animal breeding, genomics and prediction of breeding value (rodolfo j. c. cantet) animal breeders have used a plethora of statistical methods to predict breeding values when adding geno- mic information to phenotypes and to pedigree data. at the leipzig wcgalp two different models for pre- diction of breeding value entered the genomic arena: the independent multiple marker (snp) model by theo meuwissen and co-workers ( genetics , ), and the infinitesimal animal model with the covariance matrix of independent markers defined by paul vanraden ( j dairy sci , ), as worked out by ignacy misztal and co-workers (see legarra et al. j dairy sci , ) ssgblup. in vancou- ver we now witnessed (un)intentional efforts to con- verge from either side to a model that takes into account the genetic architecture of the trait and be consistent with the infinitesimal model that has served so well until now. reflecting my thoughts as somebody dealing with genetic evaluation for beef cattle: (i) i try to avoid situations where i have to compare the geno- mic and conventional methods as the existence of two different predictions of breeding value affect the confi- dence on either method; (ii) if a bull or cow has no new phenotypic data but genomic information (or not), it is easy to explain a change in the predicted breeding value from ssgblup. however, this is not easy from the snp model, in particular if imputation and bayesian algorithms have been used. the basic difficulty with both the models is that under linkage and linkage disequilibrium, genome segments rather than snps are transmitted over gen- erations. hence there are neither independent snp effects nor real permutable markers to calculate geno- mic relationships (see thompson genetics , ). therefore vanraden’s predictor of the true genomic relationship partially captures the pattern of inheritance under hardy–weinberg, but it does not take into account the genetic architecture (variable gene effects over the genome) behind the trait varia- tion. the first session on monday morning evidenced all of this. dorian garrick and vincent ducrocq pre- sented models accommodating individual markers and polygenic effects. gustavo de los campos gave a clever presentation on the difficulties in equating the estimate of the additive genetic variance from the snp model with the one from the infinitesimal model. the former works well for prediction, but it does not allow the estimation of additive variance. the search for the covariance matrix and the linear prediction model that takes into account genomic information, was pre- sented by gregor gorjanc, and also by zulma vitezica on metafounders. i showed with her how genomic information is utilized by the classic regression approach of breeding values across generations to track the mendelian sampling effects and thereby account for more additive variance than with the con- ventional animal model. when the (true) underlying genetic model is unde- fined, the accuracy of prediction cannot be defined the usual way and we cannot compare the two meth- ods of utilizing genomic information. we have been performing genetic evaluation over decades assuming the infinitesimal model, as it has proved to be consis- tent with the observations. usually overlooked by animal breeders, asymptotic theory arguments for- malizing the infinitesimal model have been given by lange ( , j math biol , ) and by abney et al. ( , am j hum genet , ). hopefully we are soon able to perform genetic evaluation (like dr. hen- derson taught us in the non-genomic era) having all the benefits of genomic information and taking into account the genetic architecture of the trait. © blackwell verlag gmbh • j. anim. breed. genet. ( ) – review beauty in black and white? race, beauty, and the fox film photogenic beauty contest in brazil suk, lena oak. . beauty in black and white? race, beauty, and the fox film photogenic beauty contest in brazil. latin american research review ( ), pp. – . doi: https://doi.org/ . /larr. history beauty in black and white? race, beauty, and the fox film photogenic beauty contest in brazil lena oak suk institute for historical studies, university of texas at austin, us lenaoaksuk@gmail.com in , the fox film corporation held a “masculine and feminine photogenic beauty contest” to find hollywood’s newest “latin” star in brazil and other countries. north american film representatives asked for contestants who were “white with latin blood.” the exotic allure of this racialized category contradicted brazilian elites’ preference for eugenic, chaste, white beauty. brazilian film critics, advertisers, and beauty contestants negotiated transnational standards of beauty as they sought faces, bodies, and sexual appeal that would conquer hollywood. ultimately, brazilian films intellectuals forged their own meanings of “white with latin blood” even as they upheld the supremacy of white beauty. however, the contest demonstrates how the transnational contours of cinema offered a liminal space for competing standards of racialized beauty in brazil. em , para descobrir um novo astro “latin,” a fox film corporation lançou no brasil e em outros países “o concurso da belleza photogênica feminina e varonil.” os representantes norte- americanos pediram que os concorrentes fossem “brancos com sangue latino.” o encanto exótico dessa categoria racializada ia contra a preferência das elites brasileiras pela beleza eugênica, pura e branca. cinéfilos, anunciantes e concorrentes negociaram padrões transnacionais de beleza enquanto buscavam rostos e corpos atraentes que conquistariam o hollywood. no final, cinéfilos brasileiros construíram seus próprios sentidos de “branco com sangue latino,” ainda que reforçando a supremacia da beleza branca. no entanto, o concurso revela como o aspecto transnacional do cinema oferecia um espaço temporário dos padrões contraditórios da beleza racializada no brasil. in , the hollywood studio fox film launched a feminine and masculine photogenic beauty contest to search for their next “latin” star in brazil, chile, and argentina. in brazil, one male and one female winner would win a grand prize: a trip to hollywood and a one-year acting contract. if the winners demonstrated “aptitude for the cinematographic art,” fox film would offer them an additional four-year contract. if they lacked this aptitude, fox would at least pay for the actors’ passage back to brazil. in order to be successful, the winning contestants had to be “white with latin blood” and exhibit “photogenia,” two elusive terms loaded with contentious racial, national, gendered, and sexual significance. brazilian film intellectuals seized the contest as an opportunity for the winners to “elevate the name of brazil” in hollywood. aspiring stars submitted their photographs, body measurements, and their fervent hopes for success. beauty, or more specifically the concept of “photogenia,” could bring the promise of stardom and prestige on cinema’s largest stage, not only for the winners but for all of brazil. the fox film photogenic beauty contest began as a hollywood invention, a publicity campaign in which north american studio executives established the parameters of acceptable beauty and decided the ultimate winners. nevertheless, film critics, intellectuals, and aspiring actors in brazil interpreted these parameters, constructing concepts of beauty and race in a transnational context. although brazilians who entered the “quem quer ser artista da fox?,” cinearte, september , , . this article aims to be part of a growing body of work on early latin american transnational film culture. laura isabel serna has analyzed mexicans’ participation in moviegoing and their interaction with hollywood transnational media as a way to construct https://doi.org/ . /larr. mailto:lenaoaksuk@gmail.com suk: beauty in black and white? contest fashioned their faces, bodies, and mannerisms to fit fox film’s standards of beauty, they were not derivative images of hollywood’s exotic ideals. rather, the fox film contest illuminates how brazilians positioned themselves within multiple, competing discourses of racialized beauty. brazilian film critics propagated early twentieth-century eugenic ideologies that privileged whiteness. at the same time, intellectuals and film fans recognized hollywood’s vogue for stars with exotic sexual allure, a quality at odds with the brazilian eugenic definition of whiteness. which type of beauty would be brazilians’ tool to conquer hollywood? brazilian film intellectuals resolved this contradiction by characterizing the winners as white individuals capable of performing hollywood fantasies of nonwhite sexuality. while the fox film beauty contest did not upset racial hierarchies or the supremacy of white beauty in brazilian intellectual discourse, it indicated how the transnational contours of cinema offered a liminal space for competing standards of racialized beauty. beauty and whiteness in brazil when the fox film studio launched the contest, it waded into dynamic intellectual and popular discussions regarding beauty, race, and national identity in brazil. in the early twentieth century, brazilian intellectuals, writers, and artists incorporated medical discourse related to eugenics to define beauty as coterminous with a racialized ideal of whiteness. in contrast to the mendelian eugenics of germany and the united states, where eugenicists sought to engineer race through reproduction and mass sterilization, latin american intellectuals selectively combined mendelian and neo-lamarckian eugenics, the latter which maintained that environmental factors were the keys to racial uplift. brazilian public health officials embarked on campaigns to vaccinate, sanitize, educate, and otherwise lift populations out of both poverty and racial degeneracy. eugenicists and public officials associated blackness not only with backwardness and poverty but with ugliness and deviant bodies. in contrast, they associated whiteness with progress, health, education, sexual chastity, and beauty (dávila ). centering beauty within early twentieth-century eugenic ideology, alvaro jarrín argues that beauty was the means to demarcate the boundaries of national belonging. “if ugliness racialized rural workers as inferior and sickly, beauty served as its mirror image and became a highly desirable trait that marked the superiority of the brazilian elites” (jarrín , ). mônica raisa schpun has similarly addressed the imbrication of health, beauty, and whiteness and how women in the s participated in sports to cultivate idealized thin, white bodies (schpun ). within this ideological context, beauty contests emerged as key forums to debate the racialized boundaries of beauty and identity in brazil. workers’ associations, afro-brazilian social clubs, and ethnically based mutual aid societies held beauty contests and debated the parameters of female beauty according to national, racial, ethnic, class, and regional identities (besse , ). however, within nationally circulating periodicals aimed at the elite and growing population of urban professionals, newspaper editors and beauty contest judges consistently upheld the eugenic ideal of whiteness as a qualifier of national beauty. in , belmonte (pseudonym of benedito carneiro bastos barret), a famed satirical cartoonist from são paulo, poked fun at the incongruity of nonwhiteness and beauty. printed in the são paulo newspaper folha da noite, “the ugliest woman of brazil” cartoon features a dark-skinned woman in elegant dress but with “ugly” features (figure ). the oversized bow adds a comic, provincial touch to her look despite the dress and jewels. she is surrounded by bags of money and jewels; the caption reads, “she will receive $ , worth of prizes, at least as a bit of consolation.” national identity and modernity in the early twentieth century. similar to the fox film contest, in mexico, the hollywood studio paramount pictures paired with mexico city movie chains to find a “star of the south” (serna , – ). for a counterpart to serna’s book, see gunckel ( ), which examines mexican-americans’ participation in transnational film culture in los angeles. for a recent compilation that addresses various latin american film markets in transnational context see navitski and poppe ( ). on film exhibition in rio de janeiro and são paulo in the early twentieth century and the competing presence of european and hollywood producers and distributors, see souza ( ), galvão ( ), and gonzaga ( ). the historiography on the presence of hollywood in brazil in the mid and late twentieth century is too extensive to present adequately here, but a classic text is tota ( ). on neo-lamarckian eugenics in latin america, see stepan ( ). there is a rich historiography on the sanitation movement in brazil. a fundamental book is a era do saneamento, recently translated to english (hochman ). jarrín’s study of plastic surgery is a contemporary ethnography, but chapter addresses the eugenic legacies of concepts like beauty and ugliness. like jarrín, dain borges has also examined the work of brazilian children’s author monteiro lobato. influenced by neo-lamarckian eugenic thought, lobato emphasized ugliness as a marker of racial degeneracy in his renderings of his famous “hillbilly” character “jeca tatu” (borges ). for mention of beauty contests in the s afro-paulista press, see butler ( , ) and alberto ( , – ). on the growth of print culture in rio de janeiro and são paulo and its readership among a nascent “middle class,” see owensby ( ). suk: beauty in black and white? when various newspapers collaborated to hold an extensive contest for “miss brazil” in , the results were an extension of this eugenic ideology. although the editors of these newspapers claimed that brazilian beauty would reflect the country’s racial diversity, they effectively barred nonwhite women from participating. susan besse points out that in contrast to the image of the “sexy mulata” that followed in later decades, descriptions and images of s beauty contestants sanitized them as “virtuous virgin/mothers” whose sexuality was limited to reproducing a eugenically superior nation (besse , ). yet, for all the medical discourse of eugenics that informed elite notions of whiteness and beauty, the s was also the decade of modern girls, jazz bands, josephine baker, the charleston, and of course, the rise of hollywood in both the us and brazil (seigel ). while hollywood studios reflected and projected a culture of white supremacy, confining african american actors to demeaning and pejorative roles, the industry also participated in the primitivist and orientalist aesthetic that was in vogue in europe and the americas. through a combination of typecasting and carefully managing publicity, hollywood studios developed a star system that categorized actors in specifically gendered, raced, and sexualized ways. for example, some actresses played the ethnically “other” and sexually aggressive “vamp,” whereas others epitomized the white, innocent, “girl-woman” (dyer ; staiger ; studlar ). rudolph valentino, an actor of italian descent, was the most famous example of the “latin lover,” the sexually aggressive, vaguely southern european or latin american antihero (studlar ; berg ; rodríguez ). by , valentino’s popularity was waning, but on august , he passed away suddenly, just a week before the beauty contest began. fox film did not plan the contest in response to his untimely death, but the studio might have reaped additional publicity in their quest to crown a new latin lover. these hollywood images percolated throughout brazil, contributing to a robust film culture. although brazilian film companies were present in various regions around the country, and the production of antiblack racism remains an issue in contemporary brazilian beauty contests, as evidenced by the online racist and regionalist criticism of recent winners (diario de pernambuco ). however, competitions for miss brazil have not always preferred white contestants. courtney j. campbell has demonstrated that the regional and national press expressed anxiety about white women representing brazil in s– s miss universe contests (campbell , ). on negative depictions of african americans in hollywood film, see guerrero ( ) black audiences in the united states still engaged with the hollywood star system and sometimes recuperated these negative images through spectatorship (stewart ). on orientalism in hollywood, see bernstein and studlar ( ). my use of “orientalist” will refer to attraction to the “other” rather than to edward said’s theoretical framework. for the representation of the star system in brazilian film magazines, but for a later time period in the s, see adamatti ( ). figure : belmonte, “a mais feia do brasil,” folha da noite, may , . acervo folha, https://acervo.folha .com.br/index.do. https://acervo.folha.com.br/index.do https://acervo.folha.com.br/index.do suk: beauty in black and white? newsreels and documentaries was prolific, hollywood dominated over percent of the brazilian film market (johnson , ). brazil was the second-largest market for hollywood films in latin america (vasey ). in addition, intellectual production related to cinema thrived across a variety of print outlets. daily newspapers and weekly magazines reported on the premieres of the latest hollywood gossip and films. a vanguard of film intellectuals formed “cine-clubs” and published magazines dedicated to the appreciation of cinema (xavier ). the contributing authors of the brazilian film magazine cinearte influenced film production and criticism for decades. founded in , cinearte had a national circulation in the tens of thousands (lucas , ), and its authors aggressively advanced a nationalist agenda. for them, cinema was a means to attain the trappings of modernity and whiteness, and they exalted these ideals in language inflected with eugenic ideology (salles gomes , ; xavier , ; bicalho , – ; schvarzman , – ). the domestic production of high-quality films would demonstrate brazilian mastery of modern technology and taste. by excluding actors of color, films could also be a means of exhibiting brazilians as a white rather than a mixed-race population (stam , , ). productions did not always conform to these standards, and images of “naked indians,” mixed-race actresses, and actors in blackface appeared in documentaries and feature films that cinearte rejected in scathing reviews. cinearte willfully aggrandized the production of brazilian films but, in the absence of consistent domestic production, devoted most of its content to news from hollywood. although earlier film scholarship characterized cinearte as evidence of hollywood’s cultural imperialism in brazil, more recent scholarship has recognized the magazine as a site for intellectual production and the development of a highly nationalist discourse on cinema and moviegoing. although the term photogenie originated in french film theory, cinearte popularized the hybrid portuguese- english term “photogenia” as a type of photogenic quality, an “aptitude for cinema” that connoted hollywood luxury, beauty, hygiene, and whiteness (xavier , ). however, photogenia also reflected hollywood’s penchant for orientalism and sexual allure. a year before the fox film contest, the writer maria eugenia celso published a short story titled “photogenica” in one of rio de janeiro’s weekly leisure magazines. in the story, a “photogenic” woman proves her aptitude for the screen by studiously mimicking the expressions and gestures of hollywood stars. she claims hollywood as her “fatherland” and plans to become rich and famous in “roles of luxury, seduction, and drama … roles that will free me to develop my powers of fascination. i want to become a vamp.” calling herself the next “nita naldi,” a hollywood actress known for her exotic vamp roles, she laughs as she literally stuns a passerby with her sexual allure. at the end of the story, she offers the most “yankee of shake-hands” and saunters away “vamp-iricamente.” celso poked fun at brazilian’s fascination with hollywood, and in particular, women’s obsession with becoming starlets. celso’s use of “photogenia” also signifies an exotic sexual allure that one could cultivate and perform. through photogenia, the woman in the story finds a sexually and racially liberating form of beauty. she aspires not to be the sanitized virgin/mother, the idealized feminine figure of eugenic whiteness. on the contrary, she seeks to be the vamp, hollywood’s exotic and dangerous “bad woman.” of course, photogenia was racially liberating to a very limited extent. brazilian racist ideology negatively condemned women of color and poor women as sexually licentious, even as these same women used the legal system to defend their honor (caulfield ). as seen throughout the contest, photogenia was a temporary performance, a privilege of those who otherwise conformed to the eugenic definition of white beauty. through photogenia, white brazilian actors and actresses could become vamps, “sportsmen,” modern girls, or even “white with latin blood.” for a brief overview of the “regional cycles,” or waves of regional production in brazil in the early twentieth century, see autran ( ) for an analysis of brazilian film production outside of rio de janeiro and são paulo, as represented through film magazines, see navitski ( ). on the growth of hollywood abroad, see thompson ( ). hollywood did not always dominate to such an extent. prior to the s was a “golden age” when brazilian film companies thrived (araújo ). robert stam ( ) refers to race in early brazilian cinema as a “structuring absence,” in which afro-brazilian culture and figures were systematically erased from filmic representation. while xavier ( ) described cinearte as a magazine with conflicting agendas, to support brazilian cinema but at the same time functioned as an agent of hollywood’s growth in brazil, stam ( , ) criticized the magazine as a derivative “tropical version of photoplay.” however, taís campelo lucas ( ) has extensively analyzed the magazine as a site of vanguard film intellectualism in brazil. a brief introduction of jean epstein’s theorization of the term in english is available here: robert farmer, “jean epstein,” senses of cinema (blog), december , , http://sensesofcinema.com/ /great-directors/jean-epstein/. maria eugenia celso, “photogenica,” para todos, october , . http://sensesofcinema.com/ /great-directors/jean-epstein/ suk: beauty in black and white? white with latin blood north americans and brazilians collaborated on various stages of the contest, and fox film’s parameters for beauty did not translate without adjustment in brazil. to launch the contest, josé matienzo, the representative of fox film in latin america, traveled to argentina, chile, and brazil, where each country held its own national contest. to enter, contestants submitted a filled-in form and a photograph measuring × centimeters. a “brazilian jury” composed of artists and writers, mostly from rio de janeiro, selected five women and five men to do a camera test. paul ivano, a brazilian who worked as a cameraman in hollywood, flew into rio de janeiro to film these tests. the resulting footage was sent to new york, where an “american jury” led by william fox and other studio executives made the final selections. from the beginning, brazilian film magazines and daily newspapers publicized and reported commentary on each stage of the contest. one of the key points of contention between hollywood and brazil was their differing interpretations of the term “latin,” a mutable term that varied across multiple national and historical contexts. michel gobat has explored how nineteenth-century elites in spanish america adopted a “latin american” identity to assert their whiteness. “latin” linked the region to europe rather than spain, which elites perceived to be racially and economically decadent. nineteenth-century brazilian elites found little use for the term “latin america” except in occasional reference to countries they perceived as successfully white, such as argentina and chile. by the early twentieth century, intellectuals in spanish america imagined latin american as an identity associated with mestizaje rather than whiteness (gobat ). however, hollywood in this same time period used the term “latin” in a different way, as a racialized category that was vaguely tied geographically to southern europe or latin america, but also signified an exotic type of aggressive sexuality. fox film explicitly sought beauty contestants who were “white with latin blood,” that is, people with white faces and bodies but with an inherent, biological characteristic of latinness in the “blood.” fox film’s first press release about the contest referenced the need to “extend opportunities to other latin countries” and to incorporate “new physiognomies and bright ideas” in their films.” fox film’s definition of the physical parameters of “white with latin blood” meant women who were sixteen to twenty-three years old, . to . meters tall, forty to fifty-five kilos, and in addition, had, “eyes that are dark when photographed.” male contestants had to be no older than twenty-eight, taller than . meters, with “a robust complexion and upbeat physical appearance; eyes that are dark when photographed.” these physical measurements were not suggestions but “necessary requirements.” on the attached form that the applicant was to clip and fill out, there were spaces to list name, address, age, marital status, height, weight, color and length of hair, and color of eyes. the form lacked any space to write in one’s skin tone or complexion. given the “requirement” that contestants be “white,” and the racial politics of both brazil and hollywood, this omission likely signified that fair skin was a nonnegotiable attribute. fox film therefore propagated specific, racialized characteristics as markers of both beauty and latinness. the fox film beauty contest also emphasized standards of gendered propriety. women who entered as minors had to have the permission of their fathers, and married women, the permission of their husbands. the first advertisement for the contest in the brazilian film magazine a scena muda announced that fox film, “convinced of the necessity of varying its casts and, having noticed their success of latin types not only in the us but in the rest of the world, has resolved to find new stars in the countries most representative of south america: brazil, argentina, and chile.” in selecting these countries, fox film focused on its largest markets in south america but also limited the contest to regions with large populations of european- descendent peoples. for fox film, the “latin race” was geographically fixed and best represented by these three countries. while fox film’s emphasis on european descent pointedly excluded indigenous, afro-descendent, and nonwhite populations, the idea of latin blood connoted the exotic sexuality exhibited by latin lovers like while the contest ran concurrently in argentina and chile, the events and outcomes in those countries are beyond the purview of this article. “primeira reunião do jury da fox,” cinearte, december , , . for a wider analysis of events surrounding the contest across various brazilian press outlets, see isabella goulart’s extensive master’s thesis (goulart ). “quem quer ser artista do fox?,” cinearte, august , , . “quem quer ser artista do fox?” cinearte, september , , . “convencida da necessidade de variar seus elencos e, tendo notado o êxito que ontem em cinematografia, não só nos estados unidos como em todo o mundo, os typos latinos, resolveu procurar novos astros nos países mais representativos da america do sul: — no brasil, na argentina e no chile.” “a ‘fox film corporation’ quer uma actriz e um actor brasileiros,” a scena muda, april , , . suk: beauty in black and white? rudolph valentino. while valentino was white enough to be represented in on-screen romances with nonethnic white actresses, gaylyn studlar has detailed the ways in which film studios cultivated valentino’s public image of ethnic nonwhiteness. male moviegoers in the united states used explicitly xenophobic language to voice their disapproval of his exotic sexuality as non-heteronormative and racially “other” (studlar ). when fox films asked for contestants to be “white with latin blood,” they did not seek the eugenic, sanitized, chaste ideal of whiteness but rather the exotic and foreign latin lover. brazilian commenters on the fox film contest infused national parameters of beauty into the transnational contest. similar to other national beauty contests at the time, brazilian writers claimed that the contest was racially inclusive but excluded anyone nonwhite. one advertisement for the contest in cinearte asked, “who will be the girl and boy that luck will take to the studios of hollywood? from where will they come? from rio de janeiro? from são paulo? from the states of the center, of the north, or the south? will they be poor or rich?” the underlying insinuation was that beauty could come from all reaches of a diverse brazil, subtly hinting at stereotypes of regional difference. moreover, contestants could be “poor or rich,” emphasizing the seemingly egalitarian nature of the contest and of photogenic beauty. according to film scholar isabella goulart, although photogenia was supposed to be an “irrefutable quality” or a mysterious type of indefinable charm, it was actually contained within specific class, ethnic, and racial categories. for this reason, the fox films contest was limited to a tiny minority of wealthy, white, elite brazilians (goulart , – ). brazilian film intellectuals however, did not reject hollywood’s demands for contestants to be “latin” or to exhibit exotic sexuality. in early publicity campaigns, the brazilian press emphasized the appeal of exotic sexuality, stressing that photogenia was distinct from conventional, eugenic notions of beauty. when one anonymous reader inquired about the contest, an editor responded, “my dear, there are ugly artists that are beautiful in photographs. it is a question of being photogenic.” for cinearte, the successful candidate had to have “something else”: “let’s hope they choose the five girls [moças] and boys [rapazes] who are truly the most photogenic, and as they intend to be stars and idols, the girls and boys who respectively have the most ‘something different’ and the most ‘sex attraction.’” there was a gendered distinction in that photogenic women should have “something different” while men had more outright “sex attraction.” however, both qualities referred to the sexual desirability of “latin” types. a scena muda echoed similar sentiments: “among the applicants, there are not just beautiful ones, but sweet ones, attractive ones [insinuantes], seductive ones, in such a way that we can affirm that, at the very least, one young man and woman will go to hollywood and elevate the name of brazil in “cinelandia” at the same time that they will smile upon fame, glory, and fortune.” although fox films had stipulated rigid physical parameters for beauty, the brazilian descriptions of the successful candidate emphasized the need to conform to expectations of the exotic, to provide “something different.” while “latin blood” signified the sensuality of the latin lover, having “white skin” could also be racially ambiguous. in the case of early hollywood film, even light-skinned actors wore heavy white makeup, which was an aesthetic and functional norm. clara rodríguez ( ) argues that the high contrast of black and white films allowed for “latin” actors with darker skin to appear lighter and gwendolyn foster ( ) depicts “whiteface” makeup as a normative, sanitized identity devoid of ethnicity. actors also used white powder to convey ethnicity and exotic foreign identities in hollywood. in his star-making turn as a middle eastern “sheik,” valentino wore thick, white pancake makeup. in fact, the use of white face powder became a significant mark of not only his ethnic otherness but of a feminized sexuality. an infamous editorial in the chicago tribune associated valentino with “pink powder” and accused him of being too feminine because of the face powder and elaborate costumes he used to portray middle eastern, french, and argentine characters (studlar , ). in this time period, the use of white face powder did not necessarily mean that one was trying to whiten or to pass as white. phenotype and skin color were important markers of racial identity in early twentieth- century brazil and, even in contemporary society, remain consistent indicators of socioeconomic outcomes. however, in an era of mass european immigration and nativist xenophobia, white skin was not an absolute sign of whiteness. in addition, writers and advertisers in women’s magazines idealized a particular type of “o concurso de belleza photogenica da ‘fox,’” cinearte, october , , c . on the racialization of region in brazil, especially the perspective of elite são paulo residents on the rest of the country, see weinstein ( ). “questionario,” cinearte, october , , . “o ultimo mez do concurso de beleza fotogênica da ‘fox film,’” a scena muda, november , , . on the racial ideology of “whitening,” though focused on heredity rather than body modification, see skidmore ( ). on colorism in contemporary brazilian society, see telles ( ). suk: beauty in black and white? white skin: a “clear” complexion with rosy cheeks. this beauty standard obviously excluded anyone with dark skin. yet, hygienists also criticized an overly “pallid” complexion as a sign of poor health and one’s lack of fresh air. intellectuals criticized white powder as “theatrical” and incapable of creating this rosy white glow (schpun , – ). a brazilian sponsor of the fox film beauty contest explicitly capitalized on the association between white face powder and a theatrical, orientalized look. the mendel perfumery pledged prize money to the female winner of the contest (though not to the male winner, even if male actors wore white powder too) and in weekly advertisements, encouraged contestants to use their products. “before posing for this important contest, improve the attractiveness of your face using: ‘revelations of the harem’ rice face powder which will whiten your skin, beautifying it, without any trace of having used artifice.” goulart points out that the mendel perfumery emphasized that their makeup hid dark skin in a “natural” process of whitening, reflecting the contradictory expectations that women cultivate beauty but also be “naturally” beautiful (goulart , ; schpun , ). however, mendel perfumery named their rice powder “revelations of the harem,” an allusion to hollywood’s imagined middle east and its perceived illicit sexuality. thus, brazilians using white face powder may not have been necessarily “whitening” themselves but “othering” themselves by using an orientalized product that explicitly recalled imagined, middle eastern harems. in her study of beauty contests in s south africa, lynn thomas ( ) argues that black women’s use of white face powder was not necessarily a form of whitening. rather, some used white powder to signal their appropriate use of a modern, global commodity. similarly, dark-skinned brazilian contestants may have appropriated the multiple meanings of a “revelations of the harem” rice face powder as a cosmetic that would make their skin whiter and thus more “appropriate” for the camera, but also as suggestive of hollywood’s desired orientalist aesthetic. “white with latin blood” was a contentious and unstable term that had variable meanings according to fox and to cinearte. although fox film explicitly called for “white” contestants who could conform to exact standards of height, weight, and coloring, the caveat of “latin blood” signified that they were not seeking “whiteness” but in fact wanted stars who would exhibit an exotic sexuality. fox films essentialized this category in terms of region, imagining that a contest held in argentina, chile, and brazil would necessarily yield this particular “physiognomy.” brazilian commentators did not ignore hollywood’s call for racialized sexuality and, in the early stages of the contest, emphasized the need for “sex-appeal” and “sex-attraction.” in the context of eugenics, which associated whiteness with chastity and hygiene, both hollywood and brazil understood “white with latin blood” as exhibiting nonwhite sexual appeal. the fox film beauty contest thus offered brazilians an alternative concept of beauty distinct from the sanitized “virgin/mother” represented by miss brazil. yet this alternative standard of beauty did not destabilize brazil’s racial hierarchies. as evidenced by the subsequent events of the contest, brazilian intellectuals and many contestants only accepted “latinness” and photogenia as temporary performances. on the pages of cinearte, only white artists had the privilege to cultivate this sexualized allure. exhibiting photogenia the men and women who entered the contest demonstrated diverse interpretations of what “white with latin blood” and “photogenic” meant to them. some contestants adhered to the eugenic definition of whiteness, taking care to ensure that they fit within the biological parameters of the contest. others offered “something else” that would set them apart as being exotic and sexually alluring, as seen in “marisa’s” seductive pose with a rose in her mouth (figure ). neither marisa nor the other contestants on the page made the final cut. the contestant carlos modesto, whom cinearte endorsed as their pick to win the contest, exhibited multiple types of masculine beauty. he submitted one photo of himself as rudolph valentino’s character in son of the sheik ( ; figure ), one as a cowboy, and a headshot of himself in a suit (figure ). the two costumed photos represented contrasting images of east and west; on the left, the exotic, orientalized middle eastern sheik, and on the right, of an “all-american” cowboy. the contrast between the headshot, which focuses on modesto’s face, and the costumed photos below, which focus on his body and clothing, create the illusion that the headshot at the top is the “real” modesto, neutral without costume. of course, all three are performances of identity, and the headshot of modesto is as much a posed, constructed image of masculinity as the costumed photos below it. however, the arrangement of the triptych reassures viewers that underneath his costumes, either as sheik or cowboy, modesto is supposed to be the suited individual at the top. “concurso da ‘fox-film,’” cinearte, september , , c . suk: beauty in black and white? figure : rudolph valentino in son of the sheik (united artists, ). figure : photographs of various contestants printed in cinearte, december , , . acervo biblioteca jenny klabin segall/museu lasar segall/ibram/minc. suk: beauty in black and white? miriam hansen has interpreted rudolph valentino’s outlandish costumes as a type of “male male impersonation,” in which the appearance of exaggerated, orientalized androgyny, and later, of hypermasculinity, destabilized binary categories of gender (hansen , – ). given the contest’s very public rules for appropriately racialized and gendered bodies, modesto’s performance is not destabilizing in the same sense. in contrast to judith butler’s ( ) theorization of drag, which exposes the artifice of gender performance, or homi bhabha’s ( ) concept of mimicry, which destabilizes the colonizer’s identity, ann mcclintock uses the term “cross-dressing” to refer to various types of gender, racial, and class performances. mcclintock cautions that not all forms of crossdressing are subversive, but that, “privileged groups can, on occasion, display their privilege precisely by the extravagant display of the right to ambiguity” (mcclintock , ). in the case of the fox film beauty contest in brazil, contestants needed to adhere to rigid standards of height, weight, and skin tone in order to be eligible. by meeting these standards, carlos modesto proved his whiteness for the purposes of the contest (regardless of his racial identity in other contexts), and was thus free to display his “right to ambiguity” on the pages of cinearte. the contrast between the outlandish costumes and the suited headshot undergirded rather than destabilized his identity as heteronormative and white. modesto wore heavy eyeliner and the racially and gender-ambiguous costume of “the sheik,” but this was clearly an orientalist fantasy. in fact, the caption stipulated that modesto costumed himself not for the contest but for a “pro-matre festival.” pro-matre was a maternalist organization founded in in rio de janeiro, part of a larger wave of charitable organizations focused on maternal and infant health care. through public festivals, galas, and parties, organizations like pro-matre occasionally provided an avenue for elite women and men to perform in theatrical plays and march in fashion shows—activities made permissible by their philanthropic aims. modesto’s affiliation with an elite philanthropic organization like pro-matre was evidence of his high social and moral status. in openly referring to pro-matre, the cinearte brazilian viewers would not have identified valentino’s or modesto’s appearance with the actual individuals who made up the diverse syrian-lebanese community in brazil. if there was a stereotypical image of the middle eastern male in brazil, he looked much less like rudolph valentino’s androgynous “sheik” and more like “giant men with giant mustaches” (lesser , ). for a revisionist take on the public work of brazilian maternalist organizations, see mott ( ). for a unique case in which a materialist organization produced their own films to uphold patriarchal gender norms in uruguay, see ehrick ( ). figure : “carlos modesto,” cinearte, december , , . acervo biblioteca jenny klabin segall/museu lasar segall/ibram/minc. suk: beauty in black and white? article justified modesto’s appearance as an androgynous, exotic identity by contextualizing it within the confines of respectable elite charity. other contestants who submitted applications and letters demonstrate the various ways in which they interpreted the parameters of “photogenia.” olyria salgado, an actress from pernambuco who starred in a filha do advogado (the lawyer’s daughter) in , filled out only the standard form that appeared in cinearte. providing her name, age, marital status, and measurements, she demonstrated the requirements for a “photogenic” body: one meter and fifty-five centimeters, forty-eight kilos. she also wrote that she had very dark brown eyes and black, “demigarconne” hair, the short bob cut distinctive to the figure of the s “modern girl.” in contrast to salgado’s concise application, diogenes leite penteado, an actor who used the stage name “diogenes nioac,” wrote an eight-page letter addressed to pedro lima. he first described himself as having a “white complexion” (tez branco), with brown hair and brown eyes, . meters tall and weighing eighty kilos. in addition to this, he claimed that he had trained in all sports, including boxing, and lately had been doing fifteen minutes of “swedish exercises” morning and night. through these physical characteristics and exercises, he justified his approximation of fox film’s definition of male photogenic beauty, including a “robust” and “athletic” body and complexion. in addition, his lengthy letter was a mini-autobiography explaining how he chose his stage name, the necessity of creating a national cinema in brazil, and funny anecdotes about his film career, including when another actress slapped him multiple times to rehearse for a film. although olyria salgado’s photogenia was expressed through her body, in her measurements and her appearance, nioac expressed photogenia as a broader concept that included his stature and skin color, charisma, and funny anecdotes. he was photogenic because he not only looked but behaved like a hollywood star, and his application letter mimicked the carefully crafted publicity materials and interviews that hollywood studios developed for their actors. nioac cultivated photogenia by training his body with swedish exercises and his personality with practiced charm. forgetting photogenia in the months and weeks leading up to the announcement of the winners, cinearte reported the anticipation surrounding the contest. “josé matienzo … lives each day called to the phone by beautiful feminine voices. every husband that can’t find his wife says it’s because of the contest and threatens to come find him.” however, after months of hype, the brazilian press deemed the contest a disappointing failure. on february , , cinearte printed the results of the camera test, from which the brazilian jury was to choose the top five men and five women. to their “frustration,” the results of the contest did not meet expectations, and while they recommended three female finalists, “all of the men were judged to be inapt.” the jury attributed the failure of the contest to “an unjust stereotype against cinema, which still exists in our midst.” they insinuated that those who might have been more photogenic did not even apply to the contest because they thought cinema was beneath them. in the section “your questions answered,” one of the editors at cinearte reiterated, “we know that there are many young men who are good types, but … they did not show up. … no, [instead] residents of the countryside were called. according to the photographs, this is who thought it was worth the trouble to apply. the contest was relatively weak, but you know that there is a stereotype against cinema.” in the brazilian magazine selecta, critic sergio silva insinuated that some women avoided the fox film contest for fear of compromising their sexual honor (goulart , ). for individuals who chose not to apply, even the temporary performance of nonwhite sexuality, or any public affiliation with cinema, presented a real offense to their notions of gendered and racial propriety. for those who did apply but were deemed “inapt,” we clearly see the limits of acceptable beauty and how the performance of photogenia was limited to an elite few. the criticism of “residents of the countryside” contradicted the statements from the first phase of the contest, which assured that photogenic contestants could come from any of brazil’s diverse regions. in stating that only “residents of the countryside” troubled themselves to apply, the editor was not referring a filha do advogado is one of the most well-known films from the “cycle of recife,” or early twentieth-century film production in the northeastern city of recife. see cunha filho ( ). on the significance of the modern girl, known as the “melindrosa,” to early twentieth-century brazilian cinema, see conde ( ). for global approaches to the modern girl, see weinbaum et al. ( ). the film was fogo de palha (flash in the pan, ), a film by canuto mendes, one of the most prolific filmmakers of the s. mendes was also a film intellectual who supported the development of “educational cinema” (saliba ). “o concurso da fox,” cinearte, january , , . “concurso de beleza fotogênica da fox film (fim),” cinearte, march , , . “questionario,” cinearte, march , , . sergio silva, “cinematographias,” selecta, february , . suk: beauty in black and white? to wealthy rural elites. he was more likely referring to negative stereotypes of a nonurban, unsophisticated, and racially degenerate population, personified in the caricature of “jeca tatu.” a cartoon figure created by brazilian children’s writer monteiro lobato in the s, jeca tatu was a cautionary tale of how laziness, poverty, and bad hygiene would cause a racially degenerate and “ugly” population (jarrín ). by april , rumors swirled that none of the finalists selected by the brazilian jury were considered photogenic enough by the north american jury. cinearte disputed this as not having the “slightest bit of truth” and urged greater patience for results. finally, in july , cinearte announced that the new york jury had selected lia torá and olympio guilherme as the female and male winners. at this point, cinearte chose not to remind readers that the brazilian jury had previously declared all the male contestants to be “inapt.” despite the language of advertisements that implied the potential winner could be from anywhere in brazil, the winners hailed from two of brazil’s wealthiest states, rio de janeiro and são paulo. lia torá was a native of rio de janeiro but spent much of her youth in spain, where she danced in a ballet company. guilherme was from an elite family of são paulo and worked as a film journalist and correspondent for cinearte. brazilian film magazines represented both winners not as “white with latin blood” but as white individuals who conformed to nationalist ideals of whiteness even as they displayed hollywood’s photogenic sexual allure. cinearte’s film critic pedro lima described torá: “her type has whatever extraordinary thing it is that attracts … she has personality, she has ‘it,’ dear reader, but she also breathes innocence.” lima claimed torá had the “it” factor, which was broadly used in hollywood media to describe a girlish type of sexual desirability, but he did not describe her as the sexually threatening and ethnically other “vamp” figure. lima instead emphasized her “innocence” and how she knew to how to be “gentle” and “docile.” cinearte’s depiction of lia torá thus conformed to the magazine’s characterization of other brazilian actresses like nita ney and lelita rosa. as maria fernanda baptista bicalho has shown, each of these actresses represented a mixture of innocence and seductiveness, a sexual allure tempered by moral respectability (bicalho , – ). even as the transnational dimensions of the fox film contest elevated torá to a larger stage, cinearte imposed its nationalist demands on torá’s off-screen persona. like carlos modesto’s varied photos, lia torá appeared in multiple editions of cinearte in different poses and costumes. when she was announced as the top finalist by the brazilian jury, cinearte published a cover photo of torá wearing a black suit and bobbed hair (figure ). her appearance, styled by the brazilian fox lobato was influenced by the hygienist movement. see note above. pedro lima, “quem é lia torá?,” cinearte, july , , . figure : lia torá, female winner of the contest. cinearte, february , , . acervo biblioteca jenny klabin segall/museu lasar segall/ibram/minc. suk: beauty in black and white? film representatives in preparation for the new york–based jury, was almost an exact replica of hollywood star louise brooks (figure ), known for her flapper roles. in both photographs, torá and brooks exhibited an androgynous look. while wearing bobbed hair, lipstick, and a masculine suit may have been acceptable for a camera test and the cover of cinearte, the magazine otherwise described torá as adhering to patriarchal standards of gendered propriety. torá’s androgynous appearance recalled images of the liberated “new woman,” but according to the rules of the contest, she had to be accompanied by her father or husband to even participate in the camera test. in a series of photographs that showed a more risqué appearance, torá demonstrated her skills as a ballerina (figure ). she is scantily clad in the top photos and wears a fringed, vaguely spanish ensemble in the bottom. in these images, torá conformed to hollywood’s demand for an exotic, sexually desirable latin star. however, cinearte couched these images, both literally and figuratively, in text that revealed this sexual desirability to be a façade. in the text that accompanied these images, the interviewer pedro lima presented torá as a childlike ingenue. he infantilized her delight at “speaking brazilian,” since she was accustomed to speaking spanish, and praised her smile, “illuminated by two rows of teeth so white that they make her seem eternally childlike.” lima even diminished torá’s intriguing admission that when she failed to secure acting roles in brazilian productions, she sought to make her own films with a home recorder. although cinearte’s informal slogan was “every brazilian film should be watched,” lima deemed torá’s foray into filmmaking to be little more than an amusing novelty, using diminutives to describe her films as “simple motifs without order, small scenes, close-ups, sometimes making her face emerge from a bundle of leaves.” according to lima, she projected her amateur films at home, surrounded by the safety and comfort of her family. in the interview, torá seemed more like the “child-woman” mary pickford, the silent film star emblematic of “all-american” girlish innocence, than the sexually charged and ethnically other “vamp” (studlar ). while the photogenic woman in celso’s story wielded her “sex-attraction” to make men into fools, lima instead described torá as exhibiting youthful innocence and moral purity. torá was only twenty years old at the time, but she was a married mother of two. yet, lima focused on descriptions of her childhood home, her relationship with her father and sister, and did not mention her husband or children. photos of torá depicted her in an androgynous suit or in a revealing leotard, but lima revealed that “underneath” these more risqué images, she was an innocent and chaste woman who stayed at home with her family. this “unveiling” of torá, in an interview appropriately titled “who is lia torá?,” resembled the unveiling of carlos modesto during the earlier stages of the contest. underneath their mutable identities, in their costumed lima, “quem é lia torá?,” . lima, “quem é lia torá?,” . figure : portrait of louise brooks. eugene robert richee, core collection, biography files, margaret herrick library. courtesy of the academy of motion pictures arts and sciences. suk: beauty in black and white? performances, modesto and torá were both “white” individuals who did not threaten hierarchies of race or challenge eugenic notions of beauty. cinearte referred to the male winner of the contest, olympio guilherme, as a heteronormative “good guy” rather than a sensual latin lover. in photographs like the one in figure , guilherme wore a business suit, rather than the exotic costumes seen on torá or the earlier contestant carlos modesto. the text of guilherme’s interview focused on his athleticism: “he has every kind of physical equipment in his house. … he has legs with such developed muscles that nobody, even without knowing him well, could doubt that every morning he runs ten kilometers without stopping.” although, according to the article, lia torá thought guilherme looked like rudolph valentino, cinearte described him as more closely adhering to the “all-american” images of masculine sportsmen stars like douglas fairbanks and george o’brien. the latter starred in action adventure films and westerns, epitomizing the strong american hero. describing olympio guilherme’s work as a journalist, lima described him in language inflected by eugenic discourse: “he has always been an indispensable part of the cultural campaign to benefit the moral sanitation of our country, just as we have done with brazilian cinema.” for the writers of cinearte, olympio guilherme was quite literally one of their own, a fellow supporter of the “physical and moral vigor of our race.” “quem é olympio guilherme?,” cinearte, july , . “quem é olympio guilherme?” figure : “quem é lia torá?,” cinearte, july , , . acervo biblioteca jenny klabin segall/museu lasar segall/ibram/minc. suk: beauty in black and white? guilherme was no moral hero, just as torá was no ingenue, but cinearte constructed these identities as the “real” personalities of the stars they sent to hollywood. when fox film launched the contest, they wanted to find their next “latin” stars who would exhibit overt sexuality and push the boundaries of acceptable whiteness: women who were exotic, seductive vamps; men who were sensual and sexually aggressive but also feminized through costume, ethnicity, and celebrity. in contrast, brazilian film intellectuals offered a different depiction of photogenia; their top stars might have the talent to exhibit “latin blood,” but underneath, they conformed to brazilian standards of gender, sexual propriety, and eugenic whiteness. epilogue in august of , lia torá and olympio guilherme headed to hollywood, a journey that cinearte chronicled as a triumphant arrival. unfortunately, in contrast to “elevating the name of brazil in hollywood,” neither torá nor guilherme had successful careers. torá starred in one feature-length film, a veiled woman ( ) before the growth of sound film ended her prospects at mainstream success. she continued to act in a handful of us spanish-language films in the s but never achieved the international fame that the contest had promised. guilherme was less successful. after a few minor roles, he returned to brazil embittered by his experience, a disappointment that he detailed in his fictionalized memoir hollywood ( ) (borge ). just as the fox film photogenic contest was ending, the results of another brazilian beauty contest were coming to fruition. in the same year of torá’s and guilherme’s departure to los angeles, four other aspiring brazilian actors expressed their own desires to conquer hollywood. contracted by the short-lived almeida films in the state of minas gerais, the actors filled out questionnaires detailing their cinematic hopes and ambitions. one of the actors, named d. mosquera, had gained a film role by entering and winning the studio’s local beauty contest. another actor, luis pimental, wrote that his professional goal was to “continue by some accounts, guilherme had impregnated another young contestant, the modernist writer patricia galvão, who was a teenager at the time. galvão also entered the fox film contest, but she later disavowed her fascination with hollywood in her famed modernist writings. a copy of the photograph she submitted can be seen in furlani and ferraz ( , ). on the circulation of hollywood’s spanish-language films and their representations of latinidad in brazil, see goulart ( ). the purpose of these questionnaires is not clear; they could have been for publicity purposes or for screening these actors for future films. the questionnaires are not dated, but they were most likely submitted in after the production of o vale dos martírios, as all of the applicants appeared in the film, and almeida films closed production soon after the film was made (enciclopédia do cinema brasileiro ). figure : “olympio guilherme: o homem que venceu o concurso da fox …,” cinearte, july , , . the autograph reads: “para todos – the great defender of brazilian artists …” acervo biblioteca jenny klabin segall/museu lasar segall/ibram/minc. suk: beauty in black and white? to be an artist and to become the rival of jack holt and von stroheim” (two hollywood actors). the one female actress of the group, hilda webber, wished to become a “star.” in response to the question of how she became an actress, she wrote, “simply by being photogenic.” webber, in fact, would not have met the “minimum requirements” for latin beauty as fox films had defined the year before. webber wrote that she had blond hair and blue eyes, so hollywood would have rejected her as a dark, latin beauty. webber was also born in estonia, and whether she was or not, she might have been stereotyped as jewish because of her eastern european origins. webber was too light to be latin in hollywood and too foreign to be a star in brazil. yet, in webber’s own interpretation of photogenia, she had the “something else” that was required to be apt for the screen. the questionnaires of almeida films are now ephemera. d. mosquera, luis pimental, hilda webber—their names and images have not lasted beyond the limited life span of nitrate film. although they never “elevated the name of brazil” in hollywood, they show how brazilian actors still positioned themselves within a transnational film culture. they formulated their own ideas of beauty, fame, and cinematic potential in response to hollywood images, but also in response to local beauty contests and film studios. the fox film contest, far from an isolated event, was a highly visible case study in how brazilians interacted with a dynamic transnational film culture to construct ideas of race, gender, and sexuality. even as they chased hollywood ideals of beauty and sexuality, brazilian intellectuals and beauty contestants by no means accepted these ideals without adaptation. far from victims of hollywood cultural imperialism, brazilians used this transnational moment to cultivate bodies and performances that exhibited hollywood’s penchant for exotic sexuality while still buttressing elite brazilians’ advocacy for white beauty. in the fox film photogenic beauty contest, hollywood solicited a racialized view of latinness, geographically fixed in the southern cone and physically fixed “in the blood” and in white faces, healthy bodies, and dark eyes. however, brazilian film intellectuals and contestants rejected this racialized definition and viewed “latinness” as more mutable. rather than inherent “in the blood,” the exotic sexuality associated with “latinness” was part of the performances, costumes, and gestures that brazilians cultivated through photogenia. ultimately, brazilian film critics decided that the winners of the fox film contest should adhere to gendered ideals of whiteness, with lia torá exhibiting sexual innocence and purity and olympio guilherme, an image of robust male athleticism. despite the search for contestants with “latin blood,” the winners did not challenge but rather exposed the centrality of whiteness to brazilian eugenic standards of beauty. beyond torá and guilherme, multiple aspiring individuals “failed” in their quest for stardom by having bodies and faces deemed inappropriate. yet, failed beauty contestants and obscure aspiring actors demonstrated their own interpretations and performances of photogenic beauty, in hopes of conquering hollywood. acknowledgements my thanks to alvaro jarrín, isabella goulart, leonardo marques, and rielle navitski, who made suggestions at various stages in the development of this article. additional thanks to the anonymous readers at the latin american research review for their constructive comments. author information lena suk is a program administrator at texas global and a research affiliate of the institute for historical studies in the department of history, university of texas at austin. her current research, which has been funded by the us fulbright program and the mellon foundation, focuses on gender and moviegoing in early twentieth-century brazil. references adamatti, 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measurement of matter–antimatter differences in beauty baryon decays articles published online: january | doi: . /nphys measurement of matter–antimatter di�erences in beauty baryon decays the lhcb collaboration† di�erences in the behaviour of matter and antimatter have been observed in k and b meson decays, but not yet in any baryon decay. such di�erences are associated with the non-invariance of fundamental interactions under the combined charge- conjugation and parity transformations, known as cp violation. here, using data from the lhcb experiment at the large hadron collider, we search for cp-violating asymmetries in the decay angle distributions of Λ b baryons decaying to pπ −π+π− and pπ−k+k− final states. these four-body hadronic decays are a promising place to search for sources of cp violation both within and beyond the standard model of particle physics. we find evidence for cp violation in Λ b to pπ −π+π− decays with a statistical significance corresponding to . standard deviations including systematic uncertainties. this represents the first evidence for cp violation in the baryon sector. the asymmetry between matter and antimatter is related to theviolation of the cp symmetry (cpv), where c and p are thecharge-conjugation and parity operators. cp violation is ac- commodated in the standard model (sm) of particle physics by the cabibbo–kobayashi–maskawa (ckm) mechanism that describes the transitions between up- and down-type quarks , , in which quark decays proceed by the emission of a virtual w boson and where the phases of the couplings change sign between quarks and antiquarks. however, the amount of cpv predicted by the ckm mechanism is not sufficient to explain our matter-dominated universe , and other sources of cpv are expected to exist. the initial discovery of cpv was in neutral k meson decays , and more recently it has been observed in b (refs , ), b+(refs – ), and b s (ref. ) meson decays, but it has never been observed in the decays of any baryon. decays of the Λ b (bud) baryon to final states consisting of hadrons with no charm quarks are predicted to have non-negligible cp asymmetries in the sm, as large as % for certain three-body decay modes . it is important to measure the size and nature of these cp asymmetries in as many decay modes as possible, to determine whether they are consistent with the ckm mechanism or, if not, what extensions to the sm would be required to explain them – . the decay processes studied in this article, Λ b →pπ − π + π − and Λ b →pπ −k+k−, are mediated by the weak interaction and governed mainly by two amplitudes, expected to be of similar magnitude, from different diagrams describing quark-level b→ uud transitions, as shown in fig. . throughout this paper the inclusion of charge-conjugate reactions is implied, unless otherwise indicated. cpv could arise from the interference of two amplitudes with relative phases that differ between particle and antiparticle decays, leading to differences in the Λ b and Λ b decay rates. the main source of this effect in the sm would be the large relative phase (referred to as α in the literature) between the product of the ckm matrix elements vubv∗ud and vtbv ∗ td, which are present in the different diagrams depicted in fig. . parity violation (pv) is also expected in weak interactions, but has never been observed in Λ b decays. to search for cp-violating effects one needs to measure cp- odd observables, which can be done by studying asymmetries in the t̂ operator. this is a unitary operator that reverses both the momentum and spin three-vectors , , and is different from the antiunitary time-reversal operator t , that also exchanges initial and final states. a non-zero cp-odd observable implies cp violation, and similar considerations apply to p-odd observables and parity violation . furthermore, different values of p-odd observables for a decay and its charge conjugate would imply cpv. in this paper, scalar triple products of final-state particle momenta in the Λ b centre-of-mass frame are studied to search for p- and cp- violating effects in four-body decays. these are defined as ct̂ =pp · (ph− ×ph+ ) for Λ b and ct̂ =pp ·(ph+ ×ph− ) for Λ b, where h and h are final-state hadrons: h =π and h =k for Λ b→pπ −k+k− and h =h =π for Λ b→pπ − π + π −. in the latter case there is an inherent ambiguity in the choice of the pion for h that is resolved by taking that with the larger momentum in the Λ b rest frame, referred to as πfast. the following asymmetries may then be defined , : at̂(ct̂)= n(ct̂ > )−n(ct̂ < ) n(ct̂ > )+n(ct̂ < ) ( ) at̂(ct̂)= n(−ct̂ > )−n(−ct̂ < ) n(−ct̂ > )+n(−ct̂ < ) ( ) where n and n are the numbers of Λ b and Λ b decays. these asymmetries are p-odd and t̂-odd and so change sign under p or t̂ transformations, that is, at̂ (ct̂ ) =−at̂ (−ct̂ ) or at̂ (ct̂ ) = −at̂ (−ct̂ ). the p- and cp-violating observables are defined as at̂-oddp = ( at̂ +at̂ ) , at̂-oddcp = ( at̂ −at̂ ) ( ) and a significant deviation from zero would signal pv or cpv, respectively. searches for cpv with triple-product asymmetries are particularly suited to Λ b four-body decays to hadrons with no charm quark thanks to the rich resonant substructure, dominated by ∆( )++→pπ+ and ρ( ) →π+π− resonances in the Λ b → pπ − π + π − final state. the observable at̂-oddcp is sensitive to the interference of t̂-even and t̂-odd amplitudes with different cp-odd (‘weak’) phases. unlike the overall asymmetry in the decay rate that is sensitive to the interference of t̂-even amplitudes, at̂-oddcp does not require a non-vanishing difference † a full list of authors and a�liations appears at the end of the paper. nature physics | vol | april | www.nature.com/naturephysics © macmillan publishers limited, part of springer nature. all rights reserved. http://dx.doi.org/ . /nphys www.nature.com/naturephysics articles nature physics doi: . /nphys b d u u d u d u u d (s) u d (s) vub v∗ud v∗td w− p t w− b d u d u u d u u d (s) u d (s) vtb bΛ bΛ − (k−)π + (k+)π −π p − (k−)π + (k+)π −π figure | dominant feynman diagrams for Λ b →pπ −π+π− and Λ b →pπ −k+k− transitions. the two diagrams show the transitions that contribute most strongly to Λ b →pπ − π + π − and Λ b →pπ −k+k− decays. in both cases, a pair of π+π− (k+k−) is produced by gluon emission from the light quarks (u,d). the di�erence is in the b quark decay that happens on the left through a virtual w− boson emission (‘tree diagram’) and on the right as a virtual w− boson emission and absorption together with a gluon emission (‘loop diagram’). the magnitudes of the two amplitudes are expected to be comparable, and each is proportional to the product of the ckm matrix elements involved, which are shown in the figure. . . . . . ev en ts /( m ev /c ) ev en ts /( m ev /c ) , , full fit part-rec. bkg. comb. bkg. lhcb a b full fit part-rec. bkg. comb. bkg. lhcb . . . . . b → p − + −Λ π π π b → k+ − − +π π π Λ b → pk− + −π π m(p − + −) [gev/c ]π π π m(p −k+k−) [gev/c ]π Λ b → p −k+k−π b → k−k+k+ −π b s → k−k+ − +π π b → pk+k−k−Λ b → pk− + −π πΛ figure | reconstructed invariant mass fits used to extract the signal yields. the invariant mass distributions for (a) Λ b →pπ − π + π − and (b) Λ b →pπ −k+k− decays are shown. a fit is overlaid on top of the data points, with solid and dotted lines describing the projections of the fit results for each of the components described in the text and listed in the legend. uncertainties on the data points are statistical only and represent one standard deviations, calculated assuming poisson-distributed entries. in the cp-invariant (‘strong’) phase between the contributing amplitudes , . the observables at̂ , at̂ , at̂-oddp and a t̂-odd cp are, by construction, largely insensitive to particle–antiparticle production asymmetries and detector-induced charge asymmetries . this article describes measurements of the cp- and p-violating asymmetries introduced in equation ( ) in Λ b →pπ − π + π − and Λ b →pπ −k+k− decays. the asymmetries are measured first for the entire phase space of the decay, integrating over all possible final-state configurations, and then in different regions of phase space so as to enhance sensitivity to localized cpv. the analysis is performed using proton–proton collision data collected by the lhcb detector, corresponding to . fb− of integrated luminosity at centre-of-mass energies of and tev, and exploits the copious production ofΛ b baryons at the lhc, which constitutes around % of all b hadrons produced . control samples of Λ b→pk − π + π − and Λ b →Λ + c π − decays, with Λ+c decaying to pk − π +, pπ−π+, and pk−k+ final states, are used to optimize the event selection and study systematic effects; the most abundant control sample consists of Λ b→Λ + c (pk − π + )π − decays mediated by b→c quark transitions in which no cpv is expected . to avoid introducing biases in the results, all aspects of the analysis, including the selection, phase space regions, and procedure used to determine the statistical significance of the results, were fixed before the data were examined. the lhcb detector , is designed to collect data of b-hadron decays produced from proton–proton collisions at the large hadron collider. it instruments a region around the proton beam axis, covering the polar angles between and mrad, where approximately % of the b-hadron decays occur . the detector includes a high-precision tracking system with a dipole magnet, providing measurements of the momentum and decay vertex position of particle decays. different types of charged particles are distinguished using information from two ring-imaging cherenkov detectors, a calorimeter and a muon system. simulated samples of Λ b signal modes and control samples are used in this analysis to verify the experimental method and to study certain systematic effects. these simulated events model the experimental conditions in detail, including the proton–proton collision, the decays of the particles, and the response of the detector. the software used is described in refs – . the online event selection is performed by a trigger system that takes fast decisions about which events to record. it consists of a hardware stage, based on information from the © macmillan publishers limited, part of springer nature. all rights reserved. nature physics | vol | april | www.nature.com/naturephysics http://dx.doi.org/ . /nphys www.nature.com/naturephysics nature physics doi: . /nphys articles table | definition of binning scheme a for the decay mode Λ b →pπ −π+π−. phase space bin m(pπ+) m(pπ−slow) m(π +π − slow), m(π +π − fast) |Φ| ( . , . ) ( , π ) ( . , . ) ( π ,π) ( . , . ) ( , π ) ( . , . ) ( π ,π) ( . , . ) ( . , . ) m(π+π−slow )< . or m(π + π − fast )< . ( , π ) ( . , . ) ( . , . ) m(π+π−slow )< . or m(π + π − fast )< . ( π ,π) ( . , . ) ( . , . ) m(π+π−slow )> . and m(π + π − fast )> . ( , π ) ( . , . ) ( . , . ) m(π+π−slow )> . and m(π + π − fast )> . ( π ,π) ( . , . ) ( . , . ) m(π+π−slow )< . or m(π + π − fast )< . ( , π ) ( . , . ) ( . , . ) m(π+π−slow )< . or m(π + π − fast )< . ( π ,π) ( . , . ) ( . , . ) m(π+π−slow )> . and m(π + π − fast )> . ( , π ) ( . , . ) ( . , . ) m(π+π−slow )> . and m(π + π − fast )> . ( π ,π) binning scheme a is defined to exploit interference patterns arising from the resonant structure of the decay. bins – focus on the region dominated by the ∆( )++→pπ+ resonance. the other eight bins are defined to study regions where pπ− resonances are present ( – ) on either side of the ρ( ) →π+π− resonances ( – ). further splitting for |Φ| lower or greater than π/ is done to reduce potential dilution of asymmetries, as suggested in ref. . masses are in units of gev/c . calorimeter and muon systems, followed by a software stage, which applies a full event reconstruction. the software trigger requires Λ b candidates to be consistent with a b-hadron decay topology, with tracks originating from a secondary vertex detached from the primary pp collision point. the mean Λ b lifetime is . ps (ref. ), which corresponds to a typical flight distance of a few millimetres in the lhcb. the Λ b→pπ −h+h− candidates are formed by combining tracks identified as protons, pions, or kaons that originate from a common vertex. the proton or antiproton identifies the candidate as a Λ b or Λ b. there are backgrounds from b-hadron decays to charm hadrons that are suppressed by reconstructing the appropriate two- or three-body invariant masses, and requiring them to differ from the known charm hadron masses by at least three times the experimental resolution. for the Λ b→Λ + c π − control mode, only the Λ b→ph +h−π− events with reconstructed ph+h− invariant mass between . and . gev/c are retained. a boosted decision tree (bdt) classifier is constructed from a set of kinematic variables that discriminate between signal and background. the signal and background training samples used for the bdt are derived from the Λ b →pk − π + π − control sample, since its kinematics and topology are similar to the decays under study; background in this sample is subtracted with the splot technique , a statistical technique to disentangle signal and background contributions. the background training sample consists of candidates that lie far from the signal mass peak, between . and . gev/c . the control modes Λ b→Λ + c (pπ + π − )π − and Λ b→Λ + c (pk −k+)π− are used to optimize the particle identification criteria for the signal mode with the same final state. for events in which multiple candidates pass all selection criteria for a given mode, one candidate is retained at random and the rest discarded. unbinned extended maximum likelihood fits to the pπ−π+π− and the pπ−k+k− invariant mass distributions are shown in fig. . the invariant mass distribution of the Λ b signal is modelled by a gaussian core with power-law tails , with the mean and the width of the gaussian determined from the fit to data. the combinatorial background is modelled by an exponential distribution with the rate parameter extracted from data. all other parameters of the fit model are taken from simulations except the yields. partially reconstructed Λ b decays are described by an empirical function convolved with a gaussian function to account for resolution effects. the shapes of backgrounds from other b-hadron decays due to incorrectly identified particles, for example, kaons identified as pions or protons identified as kaons, are modelled using simulated events. these consist mainly of Λ b→pk − π + π − and b →k+π−π−π+ decays for the Λ b→pπ − π + π − sample and of similar final states for the Λ b →pπ −k+k− sample, as shown in fig. . the yields of these contributions are obtained from fits to data reconstructed under the appropriate mass hypotheses for the final-state particles. the signal yields of Λ b →pπ − π + π − and Λ b →pπ −k+k− are , ± and , ± , respectively. this is the first observation of these decay modes. signal candidates are split into four categories according to Λ b or Λ b flavour and the sign of ct̂ or ct̂ to calculate the asymmetries defined in equations ( ) and ( ). the reconstruction efficiency for signal candidates with ct̂ > is identical to that with ct̂ < within the statistical uncertainties of the control sample, and likewise for ct̂ , which indicates that the detector and the reconstruction program do not bias this measurement. this check is performed both on the Λ b→Λ + c (pk − π + )π − data control sample and on large samples of simulated events, using yields about times those found in data, which are generated with no cp asymmetry. the cp asymmetry measured in the control sample is at̂-oddcp (Λ + c π − )=( . ± . )%, compatible with cp symmetry. the asymmetries at̂ and at̂ in the signal samples are measured with a simultaneous unbinned maximum likelihood fit to the invariant mass distributions of the different signal categories, and are found to be uncorrelated. corresponding asymmetries for each of the background components are also measured in the fit; they are found to be consistent with zero, and do not lead to significant systematic uncertainties in the signal asymmetries. the values of at̂-oddcp and at̂-oddp are then calculated from at̂ and at̂ . in four-body particle decays, the cp asymmetries may vary over Φ p +π − slowπ −fastπ figure | definition of the Φ angle. the decay planes formed by the pπ−fast (blue) and the π−slowπ + (red) systems in the Λ b rest frame. the momenta of the particles, represented by vectors, determine the two decay planes and the angle Φ∈[−π,π] (ref. ) measures their relative orientation. nature physics | vol | april | www.nature.com/naturephysics © macmillan publishers limited, part of springer nature. all rights reserved. http://dx.doi.org/ . /nphys www.nature.com/naturephysics articles nature physics doi: . /nphys a sy m m et ri es ( % ) phase space bin − − a sy m m et ri es ( % ) − − lhcb scheme a χ /ndf = . / χ /ndf = . / ˆ ap t-odd χ /ndf = . / ˆap t-odd lhcb scheme b ˆ acp t-odd χ /ndf = . / ˆacp t-odd | | (rad)Φ figure | distributions of the asymmetries. the results of the fit in each region of binning schemes a and b are shown. the asymmetries at̂-oddp and at̂-oddcp for Λ b →pπ − π + π − decays are represented by open boxes and filled circles, respectively. the error bars represent one standard deviation, calculated as the sum in quadrature of the statistical uncertainty resulting from the fit to the invariant mass distribution and the systematic uncertainties estimated as described in the main text. the values of the χ /ndf are quoted for the p- and cp-conserving hypotheses for each binning scheme, where ndf indicates the number of degrees of freedom. the phase space due to resonant contributions or their interference effects, possibly cancelling when integrated over the whole phase space. therefore, the asymmetries are measured in different regions of phase space for the Λ b →pπ − π + π − decay using two binning schemes, defined before examining the data. scheme a, defined in table , is designed to isolate regions of phase space according to their dominant resonant contributions. scheme b exploits in more detail the interference of contributions which could be visible as a function of the angle Φ between the decay planes formed by the pπ−fast and the π − slowπ + systems, as illustrated in fig. . scheme b has ten non-overlapping bins of width π/ in |Φ|. for every bin in each of the schemes, the Λ b efficiencies for ct̂ > and ct̂ < are compared and found to be equal within uncertainties, and likewise the Λ b efficiencies for ct̂ > and ct̂ < . the analysis technique is validated on the Λ b→Λ + c (pk − π + )π − control sample, for which the angle Φ is defined by the decay planes of the pk− and π+π− pairs, and on simulated signal events. the asymmetries measured in Λ b →pπ − π + π − decays with these two binning schemes are shown in fig. and reported in table , together with the integrated measurements. for each scheme individually, the compatibility with the cp-symmetry hypothesis is evaluated by means of a χ test, with χ =rt v− r, where r is the array of at̂-oddcp measurements and v is the covariance matrix, which is the sum of the statistical and systematic covariance matrices. an average systematic uncertainty, whose evaluation is discussed below, is assigned for all bins. the systematic uncertainties are assumed to be fully correlated; their contribution is small compared to the statistical uncertainties. the p-values of the cp- symmetry hypothesis are . × − and . × − for schemes a and b, respectively, corresponding to statistical significances of . and . gaussian standard deviations (σ). a similar χ test is performed on at̂-oddp measurements with p-values for the p- symmetry hypothesis of . × − ( . σ) and . × − ( . σ), for scheme a and b, respectively. the overall significance for cpv in Λ b →pπ − π + π − decays from the results of schemes a and b is determined by means of a permutation test , taking into account correlations among the results. a sample of , pseudoexperiments is generated from the data by assigning each event a random Λ b/Λ b flavour such that cp symmetry is enforced. the sign of ct̂ is unchanged if a Λ b candidate stays Λ b and reversed if the Λ b candidate becomes Λ b. the p-value of the cp-symmetry hypothesis is determined as the fraction of pseudoexperiments with χ larger than that measured in data. applying this method to the χ values from schemes a and b individually, the p-values obtained agree with those from the χ test within the uncertainty due to the limited number of pseudoexperiments. to assess a combined significance from the two schemes, the product of the two p-values measured in data is compared with the distribution of the product of the p-values of the two binning schemes from the pseudoexperiments. the fraction of pseudoexperiments whose p- value product is smaller than that seen in data determines the overall p-value of the combination of the two schemes . an overall p-value of . × − ( . σ) is obtained for the cp-symmetry hypothesis, including systematic uncertainties. for the Λ b →pπ −k+k− decays, the smaller purity and signal 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uq imj wg lo nuclc cq iiiqu cg,ou jpo pc jj jpc o pic cdnsoua btcacigcq pclc mclc j lcc pujcq mjqi couuijiioii wcsv c o, jo?wciui wp-p m- .ebi.ac.uk params is empty sys_ exception wp-p m- .ebi.ac.uk no params is empty exception params is empty / / - : : if (typeof jquery === "undefined") document.write('[script type="text/javascript" src="/corehtml/pmc/jig/ . . /js/jig.min.js"][/script]'.replace(/\[/g,string.fromcharcode( )).replace(/\]/g,string.fromcharcode( ))); // // // window.name="mainwindow"; .pmc-wm {background:transparent repeat-y top left;background-image:url(/corehtml/pmc/pmcgifs/wm-nobrand.png);background-size: auto, contain} .print-view{display:block} page not available reason: the web page address (url) that you used may be incorrect. message id: (wp-p m- .ebi.ac.uk) time: / / : : if you need further help, please send an email to pmc. include the information from the box above in your message. otherwise, click on one of the following links to continue using pmc: search the complete pmc archive. browse the contents of a specific journal in pmc. find a specific article by its citation (journal, date, volume, first page, author or article title). http://europepmc.org/abstract/med/ virtual mentor virtual mentor american medical association journal of ethics may , volume , number : - . medicine and society are cosmetic surgeons complicit in promoting suspect norms of beauty? jordan amadio some find debate on the moral acceptability of cosmetic surgery tedious, either because of that question’s tendency toward trite discourse or because of its perceived futility. even so, one can hardly ignore the urgent ethical concerns looming in the periphery of that debate. when the discourse focuses on the connection between cosmetic surgery and the societal norms that support it, it raises important questions about the physicians’ role as moral gatekeepers and their relationship to society at large that are proving increasingly relevant for the newest generation of physicians. one of the major ethical questions in cosmetic surgery is whether specialists bear any responsibility for promoting injurious standards of beauty. maggie little has called this “complicity with harmful conceptions of normality” [ ]. in his article on enhancement, erik parens explains that the potential problem is that certain types of enhancements, such as cosmetic plastic surgery, might reinforce common conceptions of normality that are detrimental to society. the notion of complicity is unusual within the field of medical ethics because it shifts the locus of bioethical inquiry from the doctor’s duty to the patient to the doctor’s duty to society as a whole, and from the effects of an inappropriate or botched treatment to those of a well-executed procedure. parens contrasts the ideas of susan bordo, who frames the patient as a victim of regrettable sociocultural and commercial forces that have made her seek surgery out of self-loathing, with the approach of kathy davis, who notes the important role of cosmetic surgery in relieving a patient’s suffering, regardless of what caused it [ ]. the synthesis of these two views, for parens, is maggie little’s suggestion that the cosmetic surgeon struggles with two sometimes opposing moral forces: first, to alleviate the suffering of the patient, irrespective of cause; second, to address potentially harmful, or “suspect,” norms that may have induced that suffering. in little’s definitive paper, suspect norms are those “whose content is steeped in injustice” [ ]. for example, cosmetic surgery designed to make blacks appear white perpetuates a suspect norm because the social value accorded to whiteness, far from being arbitrary preference, is rooted in a historical system of ugly injustice. little makes a similar argument for norms that perpetuate a “barbie doll” image as the feminine ideal, since they reinforce a value system that has subjugated and objectified women’s bodies. www.virtualmentor.org virtual mentor, may —vol complicity is the accusation that haunts the cosmetic surgeon even when debates over the acceptability of the surgery itself are bracketed. little defines the term: “one is complicitous when one endorses, promotes, or unduly benefits from norms and practices that are morally suspect” (emphasis mine) [ ]. complicity arises when a physician’s actions are felt to contribute to or support an objectionable social practice, even without directly causing harm to the individual patient. (another well- known instance of the complicity argument in medical ethics has been that of physician complicity in torture.) little asserts that, even if the surgeon is purely interested in relieving suffering, he or she can be complicit in causing that suffering by perpetuating suspect norms if he or she agrees to operate; intention to harm is not a prerequisite for moral condemnation. the status generally accorded to the medical profession adds weight to any hint of implicit endorsement. indeed, the mere fact that surgeries are performed in a health care setting can be seen as a blurring of aesthetic desires with therapeutic indications. thus, it appears that cosmetic surgeons are hard pressed to escape complicity if they serve their suffering patients’ wishes. this conundrum demands a solution that allows surgeons to mitigate their troublesome relationship to suspect norms. little’s solution draws on the externalities of the patient-doctor relationship to derive a moral duty for the cosmetic surgeon. chief among these externalities is how others in society will be affected by the decision to operate. she asks cosmetic surgeons to “locate the surgery in a broader context of naming and rejecting the evil norms” [ ]. partly, this involves practical steps such as bolstering the informed consent process to ensure that patients have an equitable view of all the options, including the no- surgery option, (which, incidentally, is something that professional medical standards already require, though in practice implementation may fall short of the ideal). but she goes much further. little’s ideal surgeon is one who “does not suggest or promote the suspect surgeries, who helps her patients explore other options, who speaks out against the pressures women face, but who occasionally uses her surgical skills in cases where there seems no other path out of true suffering” [ ]. little’s solution requires that surgeons campaign against the suspect norms that encourage some forms of cosmetic surgery. even if a norm of beauty is culturally determined, however, it does not necessarily follow that the norm is suspect. therefore, little’s argument does not apply to all cases of cosmetic surgery; some may be motivated by mere preference or by standards of beauty that are not particularly oppressive to others. the man who asks for an otoplasty to fix his awkwardly protruding ears may be reacting to social pressures, but not pressures that discriminate against a historically stigmatized group. in cosmetic nose surgery, where ethnic traits are often differentiated, it is harder to disentangle aesthetics from suspect norms. the implications of these questions reach far beyond cosmetic surgery. two are particularly salient for the generation of physicians now launching their careers: the virtual mentor, may —vol www.virtualmentor.org role of a physician as moral gatekeeper and the nature of a physician’s responsibility to society. physician as moral gatekeeper little suggests that a cosmetic surgeon’s duty to a particular patient’s welfare is part of a general duty to evaluate the ethics underlying the procedure under consideration. we are familiar with physicians acting as moral gatekeepers by being conscientious objectors to abortion, assisted reproduction for single mothers and homosexuals, or other practices with which their personal views do not concord. but there are reasons to imagine that, in practice, physicians may not care to engage in the type of unrealistic moral activism that little proposes. ultimately, the role of a moral gatekeeper is one that some physicians may be neither eager nor equipped to take on. to ask surgeons to maintain equipoise in treatment options for prospective cosmetic surgery patients is quite appropriate; indeed, such conduct is mandated by the professional standards of every medical society. but to seriously suggest that cosmetic surgeons publicly campaign against their own profession is effectively to encourage cognitive dissonance. it is possible to conceive of a middle ground where cosmetic surgeons could promote diversity and acceptance of a range of “normal appearance” [ ] without turning away individual patients. but it seems unreasonable to insist that we ought to require such activism of practitioners who provide enhancement-oriented or cosmetic services. responsibilities of the doctor-society relationship the moral gatekeeper problem is a special case of the broader question regarding the scope of the doctor’s duty. must physicians attend to the concerns of society as a whole as well as the needs of their patients? little’s proposal assumes that the surgeon has two duties to her patients: to alleviate individual suffering, and to engage suspect societal norms regarding appearance. a common justification for performing cosmetic procedures—even in extreme cases, such as sex reassignment or voluntary amputation—is that the relief of individual suffering is the predominant aim of the physician. little argues, however, that countervailing moral obligations to society may in some cases outweigh individual needs addressed in the privacy of the clinic. in such cases, the doctor-patient relationship, so often viewed as sacrosanct, is subordinated to that between doctor and society. this argument is not unlike others emerging in the health policy arena, wherein the behavior of physicians has come under increasing scrutiny. little’s view of complicity categorizes a medical procedure as immoral if it alleviates an individual’s suffering at what little deems a disproportionate cost to society. it is similar to the objection to using taxpayer dollars to pay for expensive chemotherapy with little life- extending capacity, and other variations on this theme. today, confronting a tragedy of the commons due to the exploding costs of health care, we increasingly find pressure for physicians to serve as agents of social welfare by attenuating their behavior in clinical encounters to serve group, rather than individual, aims. www.virtualmentor.org virtual mentor, may —vol this pressure has coincided with the education of a new generation of physicians, whose mission is migrating toward awareness of global health, health policy, and the concerns of medical care at the population level. anecdotally, the rising prevalence of md/mba, md/mph, and md/mpp joint degree programs attests to the growing commitment to economic, social, and political matters among doctors in training, whereas previous generations of physicians were trained to regard the moral obligation to individual patients as medicine’s summum bonum. conclusion physicians retain a special role in society that carries unique moral responsibilities. owing to his or her professional obligation, a cosmetic surgeon is unlike nonphysicians who provide mere consumer services. this explains, in part, why so much attention has been paid to the moral concerns surrounding the provision of cosmetic surgery. patients who seek these surgeries are themselves in a special position. in their paper on complicity in the arena of neuroenhancement, ravelingien et al. propose a savvy counterpoint to little’s location of responsibility; they point out that a faithful consideration of kantian autonomy as a bioethical principle requires that patients share the burden of complicity with their doctors [ ]. if anything, they argue, respect for persons and self-determination require us to reinforce joint patient-doctor responsibility for both decisions and consequences. complicity with suspect norms of appearance, as maggie little describes it, is among the most sophisticated objections raised to cosmetic surgery. it neither vilifies existing practices nor compels us to blame surgeons for practicing their art. instead, little proposes a solution that allows cosmetic surgeons to mitigate their complicity by fighting the suspect norms that drive some patients to their clinics. however unrealistic or incomplete, little’s proposal should spur medical professionals to consider the larger implications of the complicity problem. ought physicians to serve as moral gatekeepers? what is the extent of physicians’ responsibility to society at large versus that to individual patients? as the complicity question broadens to other forms of enhancement, and as a new generation of physicians emerges in a context where the doctor-society relationship is given more emphasis than before, these questions become ever more worthy of focus. references . parens e. is better always good? the enhancement project. in: parens e, ed. enhancing human traits: ethical and social implications. washington, dc: georgetown university press; : . . parens, - . . little mo. cosmetic surgery, suspect norms, and the ethics of complicity. in: parens e, ed. enhancing human traits: ethical and social implications. washington, dc: georgetown university press; : . . little . virtual mentor, may —vol www.virtualmentor.org . little . . little . . changing faces web site. http://www.changingfaces.org.uk. accessed april , . . ravelingien a, braeckman j, crevits l, de ridder d, mortier e. ‘cosmetic neurology’ and the moral complicity argument. neuroethics. ; ( ): - . jordan amadio will receive his medical degree from harvard medical school in the harvard-mit hst program and his mba from harvard business school in spring . prior to medical school, he studied science and bioethics at princeton. starting in , he will be a neurosurgery resident at emory university. his interests include the relationship of neuroscience to morality and the interconnections between biology and culture. related in vm the “mommy makeover” package, may advertising cosmetic surgery, may ama code of medical ethics’ opinion on advertising and publicity, may the viewpoints expressed on this site are those of the authors and do not necessarily reflect the views and policies of the ama. copyright american medical association. all rights reserved. www.virtualmentor.org virtual mentor, may —vol http://virtualmentor.ama-assn.org/ / /ccas - .html http://virtualmentor.ama-assn.org/ / /mhst - .html http://virtualmentor.ama-assn.org/ / /coet - .html haaga-helia huom! tÄmÄ on rinnakkaistallenne. käytä viittauksessa alkuperäistä lähdettä: vuori, j. ( ). excellent prospects for beautiful minds: marketing international education. international journal of educational management, ( ), - . http://dx.doi.org/ . /ijem- - - please note! this is parallel published version of the original article. to cite this article: vuori, j. ( ). excellent prospects for beautiful minds: marketing international education. international journal of educational management, ( ), - . http://dx.doi.org/ . /ijem- - - http://dx.doi.org/ . /ijem- - - http://dx.doi.org/ . /ijem- - - excellent prospects for beautiful minds: marketing international education introduction marketing concepts and theories are increasingly used by higher education institutions (heis) in the global education market (hayes, ; hemsley-brown and oplatka, ; hemsley-brown, ). some writers have no difficulty applying marketing theories into higher education by referring to education as either a product or service, describing university students as customers and using tools associated with emotional and brand marketing (anctil, ; durkin et al., ; hayes, ; ivy, ; moogan, ; mulnix et al., ; ross et al., ; vauterin et al., ; wright, ). for these authors, marketing is a means to ensure long-term student satisfaction which is achieved through a wide range of activities that are tailored on student needs. marketing decisions are not only generated based on marketing communications but on the offered product, price, place, people, physical facilities and processes (ivy, ). the role of marketing communication is to provide information which helps the informed customer to make the right decision. there are, however, critics who warn of the consequences of treating students as customers. critics argue that higher education marketing blurs the intellectual function of university by providing the university with a role as a service provider. in addition, critics suggest that marketing messages alter the perception of academic work and warn of the consequences of marketing campaigns that address prospective students as customers. much criticism has also been raised towards marketing in its effort to emphasise degrees and gained skills as end results instead of concentrating on advancing learning and research. moreover, marketing is blamed for obscuring the role of the academy as a place for intellectual pursuit in its tendency to emphasise the “student experience”. (acevedo, ; arambewela, ; askehave, ; gibbs, ; grebennikov and shah, ; molesworth et al., ; naidoo and jamieson, ; newman and jahdi, ; ramachandran, ; stachowski, ; svensson and wood, ; symes, ; williams, .) arambewela ( ) argues that student consumerism is the dominant discourse of higher education globalisation. international education offers heis not only new funding opportunities but also means to ensure qualified future labour force for the needs of the knowledge economy. the vocational agenda in its emphasis on employability is thus at the core of globalisation discussion. moreover, according to arambewela ( ) the promotion of student experience is an outcome of higher education marketisation and commodification. the student experience is a concept used to describe constantly changing student perceptions of both academic and non-academic life. when trying to get a deeper insight in the higher education globalisation the examination of marketing communications of heis is relevant because it is through these messages the heis try to convince prospective students to “choose us” and differentiate themselves from international competitors. finnish heis attempt to get their share of the international education market, too. the internationalisation strategy for finnish higher education aims to increase the number of international degree students (finnish ministry of education, ). international students are necessary because the population demographics indicate a growing trend of retirement and resulting shortage of future talent in the labour market. moreover, in a country where tuition-free higher education has traditionally been one of the core higher education values, the ministry of education and culture has launched a trial that allows master’s programmes to charge tuition from students from non-eu/eea countries. these simultaneous objectives are arguably contradictory (cai and kivistö, ). however, the objectives reflect the global higher education discourse in an enlightening way. many heis are attempting to attract more applicants simultaneously to their free and tuition fee programmes. as a consequence, prospective students struggle to locate accurate information on whether finnish higher education will remain free. much responsibility is given to the marketers of international programmes, who, if participating in the tuition fee experiment, are required to be specific in their marketing regarding the tuition fees and grant opportunities (pyykkö et al., ). finnish higher education consists of two sectors of almost equal size: research universities and universities of applied sciences (uass). although both sectors provide bachelor’s and master’s degrees, their missions differ. research universities are oriented towards scientific research and are in charge of doctoral education in the country whereas research and development activities within uass represent a minor activity compared to teaching. instead of scientific research uass conduct applied research which tries to boost regional innovation and economy and have relevance to professional education and practice. according to a recent international evaluation the undergraduate students’ involvement in research and development activities is a “striking feature” of teaching- research nexus at finnish uass (maassen et al., ). both higher education sectors have successfully attracted non-finnish students and created international degree programmes resulting in growing student numbers in the last fifteen years. in spring , there were , international students enrolled in international programmes of which programmes were offered by finnish universities and by finnish uass (välimaa et al., ). the outcomes of the tuition fee trial have been less successful. in , there were tuition paying degree students, of which covered their studies entirely or partially with an institutional grant. in of the students coming from outside eu/eea –area to tuition programmes and only students financed their studies on their own. finnish heis participating in the tuition experiment acknowledge the necessity to improve their marketing competence and admit that they presently use similar marketing strategies for both free and tuition fee programmes (pyykkö et al., ; pyykkö et al., ). students have also criticised the marketing efforts of finnish uass (union of students in finnish universities of applied sciences, ; ). although not specifically referring to international student recruitment, students accuse uass of misleading marketing practices and creating false images in student recruitment campaigns. students even claim that the names of degree programmes have been modified to be more attractive to potential applicants (union of students …, ). students demand heis to be truthful in their marketing and request that instead of portraying false images heis should provide prospective students with facts such as application and graduation statistics. moreover, students insist that applicants should have access to course descriptions in order to verify the claims of marketing campaigns. the accusations of uas student union is supported by a survey according to which % of uas students were dissatisfied with the truthfulness of their institution’s marketing (lavikainen, ). according to this survey, students’ disappointment was a result of a mismatch between the expectations that had been created in the application period and the reality the students faced once admitted. the mismatch related to the quality of teaching, actual course selection opportunities, the experienced level of internationalisation, perceived opportunities to collaborate with the representatives of the industry and the lack of either practical or theoretical orientation in studies. although heis representatives and their students have criticised marketing practices, finnish higher education marketing is largely unstudied. this paper examines the admissions websites of international business and technology programmes and is the first comprehensive study of the marketing communication practises of international higher education programmes in finland. the research question is: how do the programmes articulate market differentiation on their websites? the analysis is further guided through examination of the two major themes related to the discussion of marketisation of global higher education: how do the international programmes promote the vocational agenda and student experience in their online marketing? moreover, as the programme sample has been collected within the timeframe of finnish tuition-fee experiment it offers an opportunity to examine whether the marketing messages of free and tuition-collecting programmes differ. this study contributes to the study of global international market mechanisms and research on marketing communication practised by higher education institutions. marketing international higher education the goal of market differentiation is to communicate to the target audience how the offered product or service suits customer requirements better than any other available option. the communication should be so convincing that it leads to action. when promoting higher education programmes, marketers must emphasise the differentiating characteristics or qualities that are more appealing to potential applicants than those offered by other programmes. moreover, higher education marketers must assure the applicants that they are making the correct decision. in higher education, however, differences are often small and difficult to observe. therefore, the marketer of higher education programme is advised to accentuate the present subtle differences that are not apparent to the audience (anctil, ; hayes, ; van rooij and lemp, ). the knowledge of the customer needs, should be the basis for all marketing activities and a starting point for institutional market differentiation strategies. previous research has shown that applicants decide to study abroad based on both push and pull factors (wilkins et al., ). push factors refer to the opportunities and conditions in the students’ home countries, whereas the pull factors refer to the quality of education and reputation of the target country or institution and opportunities for language improvement and cultural experiences. in addition, personal and human factors, attitudes towards religion and safety and the influence of reference groups and social networks have been observed to contribute to study abroad decisions. due to the general lack of studies on motivation to study in non-english speaking countries (wilkings et al, ) and the non- existence of such research in finland particularly (cai and kivistö, ), the marketing differentiation efforts of finnish heis are hardly based on true detection of the needs and requirements of prospective international students. international student marketing uses multiple promotional tools and channels. in addition to institutional websites and published marketing material, finnish heis, for example, advertise through educational portals, attend educational fairs and arrange entrance examinations outside of europe (välimaa et al., ). however, as “online mirrors of institutional environment” (cohen et al., : ), institutional websites are critical for convincing potential students to “choose us”. previous studies on the use of websites for internationalisation purposes have been performed with different approaches in different contexts. these studies have accounted for both the actions of applicants (gomes and murphy, ; hemsley-brown, ) and institutions (bishop, ; cohen et al., ; ooi et al., ). the international degree programme descriptions of four finnish hei websites have been examined by saarinen and nikula ( ) in their investigation of the role of language in the internationalisation policy of finnish higher education. however, none of these studies has focused on how the websites communicate the marketing differentiation strategies of international programmes. data and methods the data were collected in march from the webpages of finnish heis that recruited students in english language business or technology programmes (appendix ). these study fields were chosen because in spring , they covered percent of the international degree programmes of finnish research universities and percent of the international programmes offered by uass (välimaa et al. ). these programmes are also important in the global marketplace because they are among those that have been most lucrative for new universities when becoming involved in the international student market (hemsley-brown, ). the examination included both bachelor’s and master’s degree programmes. the sample covered the main university admissions webpage and subsequent pages leading to the descriptions of the degree programmes. the analysis was conducted based on the text but excluded pictures and videos. pdf-attachments or student and alumni stories were excluded. if several technology or business programmes were advertised by an hei, the initially introduced programme was sampled, except if it was a joint or multidisciplinary programme, in which case the subsequent programme was selected. two other exceptions were generated, thus disregarding the first introduced programme in favour of the second. these programmes - an architectural and a management assistant programme - were considered to represent special niches among the mainstream business and technology programmes. this strategy yielded a total of international degree programmes from finnish uass and finnish universities. the sample covered admissions texts of business and technology programmes. thirty-eight programmes were bachelor’s and were master’s programmes. one-half (n= ) of the master’s programmes charged tuition fees from non-eu/eea citizens from , – , euros per academic year. the method of the analysis was qualitative content analysis. instead of quantifying the themes, the aim of the examination was to richly describe the themes introduced in the texts. both deductive and inductive coding was used to construct the theme categories. the texts were initially repeatedly read and then coded into wide categories of marketing differentiation topics proposed by anctil ( ). the author suggests that heis could articulate marketing differentiation based on their ) academic reputation, ) social life and campus amenities and ) the halo effect on the athletic programme. this coding cycle confirmed that these themes, which refer to north american student recruitment practice, are not applicable to the finnish context because the data contained few references to campus amenities and only one reference to an athletic programme. thus, the last category was omitted. the categories of academic reputation and social life were then coded into smaller subgroups as illustrated in table and are further described in the following. quotations from the original texts are included to illustrate how the themes were introduced in the admissions texts. table here academic reputation anctil ( ) advises heis to provide evidence of their academic reputation by emphasising a favourable ranking status and connect to the reputation with either academic postgraduate activities or occupational outcomes. the academic reputation building themes observed on the finnish programme websites were ) formal programme recognitions and achievements of the teaching staff, ) labour market relevance and graduates’ career prospects and ) teaching and research orientations of the programmes. in the data, only a small minority of the programmes communicated academic reputation by referring to ranking status, accreditation or prizes and nominations received. whereas most of these texts provided the reader with specific details, there were also texts that caused the reader to question the accreditation or ranking that was referred to. similarly, there was a range of expressions from specific to vague when the achievements of the teaching staff were introduced. whereas one institution (Åbo akademi university) provided specific details of an award obtained by a professor, the professors at the hanken school of economics were described as “well-known”, and at the university of vaasa, the recipients had “received several international research awards”. in other cases, the quality of the staff was advertised by referring to their business or international background in general terms, including “our lecturers have extensive business experience and international careers” (tampere uas). instead of referring to scholarly reputation, it was more common to emphasise the reputation that programmes have among businesses. the co-operation with the labour market was heavily promoted by indicating its role in ensuring curriculum relevancy, providing placements and projects, enabling practice-oriented teaching and increasing graduate employment opportunities. metropolia and its teachers have the best company and work life networks. (metropolia uas) our education receives acclaim from employers because our teaching meets the demands of modern working life well. (university of vaasa) our programme is designed in cooperation with business representatives to enhance your future career prospects. (lappeenranta university of technology) the degree programmes strongly accentuated the future employment prospects of their graduates. typically, these prospects were communicated by a paragraph describing the labour needs in the field and linking these needs to the curriculum. modern business development often requires close interaction with both customers and suppliers, and therefore industrial marketing and global sourcing strategies are the cornerstones of our programme. in addition to theoretical understanding, the programme emphasises the practical competencies that young graduates need when managing and developing business processes in international markets. (tampere university of technology) with the aim to specify career prospects, it was typical, particularly to the bachelor programmes, to provide examples of the titles that their graduates would obtain after graduation. some programmes were confident with their promises for the future: “graduates are highly competitive knowledge workers in the global labour markets” (haaga-helia uas), “you will be able to establish and lead business activities in any nordic country” (arcada uas) and the “degree guarantees work opportunities that are related to business management, marketing, export and import activities as well as product and service development” (karelia uas). programmes that did not want to provide such large promises favoured sentences using “may” or “can” and included lists of typical or representative titles or occupations of their former graduates. through studies in engineering physics and mathematics you can become an internationally recognized scholar or expert, start up your own company or become a business consultant. (aalto university) you can be a designer, a developer, a tester, a supervisor, an operator, a marketing or sales engineer, a project engineer, a government or local agency official or involved in professional association work. (satakunta uas) more than one-half of the programmes referred to teaching methods on their websites, thus portraying a variety of pedagogic orientations. in addition to promoting company projects, heis advertised the “latest learning technologies” (turku uas) and “innovative” (lappeenranta university of technology) or “interactive and collaborative” (saimaa uas) teaching methods and provided the reader with examples such as simulation games, role playing, case-studies and problem-based learning. in particular, master’s programmes emphasised that studying can be combined with full-time work, “study while you are building your career” (hämeenlinna uas)”, and advertised the convenience of weekend lectures, e-learning or study options that can occur “at times and in order chosen by the students” (laurea uas). in addition, elective courses were promoted for students to customise the curriculum to their individual needs. this customisation was promoted using messages such as “tailor your education to your particular needs and interests” (arcada uas) and promises of “flexibility to pursue your own interests” (mikkeli uas). whereas both sectors emphasised the teaching-research nexus through collaboration with working life, research universities also provided more general statements of the nexus promoting that “education and research are closely intertwined” (university of turku) or that “a deep scientific basis of the education is ensured” (lappeenranta university of technology). these institutions also used “scientific” or “academic” research terminology to differentiate their research from uass that, according to their mission, conduct applied research. the importance of connections with the labour market was not only highly promoted to ensure academic reputation and practise oriented teaching methods, but the physical proximity to companies was also mentioned as an advantage when the hei location was promoted. social life after studying potential us college applicants, capraro et al. ( ) concluded that the perceived social life is at least as important as the perceived quality of education. therefore, the researchers recommend heis to promote personal and social interactions on campus so applicants could feel welcome. in the admissions texts of finnish international programmes, two subcategories of the social life theme were distinguished: ) personal guidance and individual advice and ) atmosphere. whereas finnish universities offer more international programmes than finnish uas, the number of students in the university programmes is smaller (välimaa et al., ). however, programmes from both sectors advertised opportunities of personal guidance and the availability of the staff for their students. the departments are small and former students say that it was easy to feel at home at the university. the contact between teachers and students is good. (Åbo akademi university) to facilitate adaptation to the new learning environment and processes, we will have a consultation with every student about his or her orientation, on the basis of which we make a personal curriculum for each one. (saimaa uas). the student community was described as “tight-knit” (aalto university), “real” (centria uas), and able to provide personal networks for a lifetime (hämeenlinna uas, hanken school of economics), whereas the environment was described as “relaxed and informal” (tampere university of technology) or “intimate” (hanken school of education). however, the student community or atmosphere was frequently described as “international”. internationalisation was explained by providing references to a multicultural student body and teaching staff and emphasising opportunities to study abroad through international networks. some programmes differentiated themselves as more international than others by promoting themselves as “highly”, “genuinely” or “truly” international. our multicultural teaching staff, daily involvement in classroom activities with students from all over the world, our active contact with business life and our global network add to the international flavour of the programme. (jyväskylä uas) studying in multicultural teams gives you an excellent opportunity to learn about various cultures and to create valuable relationships and international networks. (saimaa uas) conclusions this study investigated marketing communication practises of international higher education programmes in finland by analysing how business and technology degree programmes on both bachelor and master levels promoted the vocational agenda and student experiences in their websites when trying to articulate market differentiation. in addition, the marketing messages of master-level programmes which collect tuition-fees were compared with those who do not. the findings indicated that the marketing messages contained plenty of references to the vocational agenda while the references to student experience concentrated on the academic affairs. differences between tuition- collecting and free programmes were not found. the results of this study show that when finnish hei international programmes want to attract prospective students to their business and technology programmes, the “beautiful minds”, as addressed by lappeenranta university of technology, they strongly emphasise the labour market relevance of the degree. the finnish heis thus echo the vocational agenda and accentuate the value of a degree as contribution to the economy. higher education is marketed as a means to an end, not as an end itself. a degree programme is promoted as a technical endeavour which provides the most efficient way to acquire the skills demanded by the global labour market. the labour market relevance overshadows the value of higher education as pursuit of critical and independent thought. (arambewela, ; gibbs, ; newman and jahdi, ; molesworth et al., ; williams, ). in their student recruitment, programmes at both research universities and uass emphasise the skills to be gained, the value of the degree in the labour market and present collaboration opportunities with companies. the labour market relevance was promoted on the websites by advertising graduates’ employability skills, emphasising the employers’ role in curriculum design, providing the names of companies in the co- operation network, referring to projects and placements that will be provided through these networks, underscoring practical teaching methods and emphasising the teaching- research nexus in collaboration with industrial networks. the strong market orientation was also evident when the programmes promoted their location by referring to the city’s active business life or business network opportunities on campus. the strong consumeristic orientation was further emphasised by programmes in both sectors referring to education as an “investment in the future” (williams, ), emphasising opportunities to tailor studies according to individual needs and by promising “excellent” career prospects. the career prospects were promoted through lists of jobs the students are able to get after graduation. the international nature of the programme was also promoted as an opportunity to gain a further differentiating competitive advantage in global market. finnish heis can promise lucrative futures and offer lists of dream jobs because there are no regulations that would force heis to provide evidence of graduate employment, as the heis in britain, for example, are required to do (williams, ). however, the websites of finnish international programmes cannot be criticised for over- emphasising the non-academic aspects of student experience. the references to atmosphere and relationships in the community were given either in connection with learning or accentuating the future benefits of the networks that students havebuilt during their studies. the heis were thus regarded as places where one obtains employability skills and references to the non-academic side of student experience was almost non- existent. in this respect the results differ from those of askehave ( ), jacob et al. ( ) and symes ( ) who in their studies showed that heis were promoted as tourist destinations, country clubs or theme parks. moreover, the websites portrayed a wide variety of examples of the heis searching for market differentiation through pedagogic orientation, the use of student-centred teaching methods, involving students in research and development activities, dedication to personal study guidance and commitment to create a working atmosphere where students and staff support individual study efforts. this study provided further proof that finnish heis’ observations use similar marketing techniques for free and tuition fee programmes (pyykkö et al., ; ). while a previous study has shown that finnish higher education students have contradictory views on whether they want to be seen as customers (vuori, ), the findings of this study indicated that the main approach for communicating with potential applicants of international business and technology programmes was addressing prospective students as customers (acevedo, ; naidoo and jamieson, ; molesworth, nixon and scullion, ; ramachandran, ; svensson and wood, ; vuori, ; williams, ) and used similar rhetoric emphasising what “we” can offer “you” to make “your” individual goals come true. discussion with an orientation towards qualitative research, this study aimed at transferability by establishing connections between its results and the results or argumentations presented in previous discussions of higher education marketing. moreover, this study was systematic in its attempt to create dependability by showing consistency in the manner it was reported and confirmability by attempting to connect the data so it could be understood by the readers (eriksson and kovalainen, ). this study concentrated on business and technology programmes because these are the major fields in which finnish heis have established international programmes. these fields are also market-oriented by the nature of their disciplines. thus, a further study should analyse whether the emphasis on instrumental educational values would manifest itself in a similar manner in other study fields. whereas this study was based on text only a further investigation of photographs and student narratives, would provide further insight into marketing differentiation efforts and possibly open new insights into the marketing of non-academic parts of student experience. this research area would also benefit from comparative international studies taking also different legislative restrictions into account. marketing should not be of interest of the marketing departments of heis only, but a concern of everyone having a stake at higher education. marketing messages used for recruiting students have an effect on students’ perceptions of their relationship with their university (svensson and wood, ; ramachandran, ; stachowski, ). for that reason, academics, maybe higher education researchers in particular, should not only be aware of the possible clashes between the messages sent by their institution’s marketing department with their own values but could also initiate either general or institutional-level discussions on the special nature of higher education marketing. considering the results of this study, it not difficult to share the critique of uas students when they argue that higher education marketing in finland is not always based on facts (lavikainen, , union of students…, ; ). the marketing messages in the sample consistently gave either indications or direct promises of future employment prospects that are certainly beyond the heis to control. the finnish heis could benefit from this study by taking a critical look at their own marketing differentiation activities. instead of promising anything on the behalf of employers, heis could, as multiple examples in this study have shown, emphasise their own achievements by highlighting the development of teaching methods and the special characteristics of their learning communities. references acevedo, a. 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( ), "student choice in higher education: motivations for choosing to study at an international branch campus", journal of studies in international education, vol. , no. , pp. - . williams, j. ( ), consuming higher education: why learning can't be bought, bloomsbury, london. wright, r.e. ( ), "marketing orientations and higher education: applications and implications", the journal of applied business and economics, vol. , no. , pp. - . http://samok.fi/ / / /korkeakoulujen-markkinoiden-on-perustuttava-tosiasioihin/ http://samok.fi/ / / /korkeakoulujen-markkinoiden-on-perustuttava-tosiasioihin/ http://samok.fi/ / / /korkeakoulujen-hakumainonta-faktatietoon-pohjautuvaksi/ http://samok.fi/ / / /korkeakoulujen-hakumainonta-faktatietoon-pohjautuvaksi/ appendix . list of documents: (accessed - march ) higher education institution bachelor programmes: degree programme in … master programmes: degree programme in… /master's degree programme in… aalto university  international business  engineering physics and mathematics  accounting arcada uas  international business plastics technology  international business management centria uas  business management  industrial management haaga-helia uas  international business  international business management* hanken school of economics  corporate governance hämeenlinna uas  automation engineering  international business  business management and entrepreneurship jyväskylä uas  logistics engineering  international business  information technology*  international business management* kajaani uas  international business karelia uas  international business kemi-tornio uas  business information technology kymenlaakso uas  international business  international business management* lahti uas  international business  international business management lappeenranta university of technology  international marketing management*  chemical and process engineering* laurea uas  business management  service innovation and design* metropolia uas  business and logistics  business informatics  civil engineering  industrial management mikkeli uas  business management  environmental engineering novia uas  environmental engineering oulu uas  business information technology  information technology  industrial management rovaniemi uas  innovative business services  information technology saimaa uas  international business  mechanical engineering and production technology  international business management satakunta uas  environmental engineering  international business and marketing logistics  business management and entrepreneurship savonia uas  industrial management  international business  industrial management* seinäjoki uas  international business tampere university of technology  business and technology tampere uas  environmental engineering  international business  dp in information technology* turku uas  international business  information technology  international business management* university of eastern finland  service management university of jyväskylä  corporate environmental management university of oulu  finance  computer vision and signal processing university of turku  futures studies university of vaasa  finance  telecommunication engineering vaasa uas  international business  information technology Åbo akademi universitiy  chemical engineering *charging tuition fees rinnakkaistallennus .pdf finalversionbeautiful.pdf encoding beauty research highlights plant genomics encoding beauty nature http://doi.org/dg ( ). waterlily species are widely cultivated plants attractive for their beautiful flowers. phylogenetically, they belong to the angiosperm order nymphaeales, a lineage that diverged from the core angiosperms during the early evolution of flowering plants. using up-to-date sequencing technology, liangsheng zhang from the fujian agriculture and forestry university, china, and colleagues obtained a high- quality genome of the blue petal waterlily (nymphaea colorata). their analyses elucidate the evolution of waterlilies and the early flowering plants. the researchers carried out phylogenomic analysis using orthologous low-copy nuclear genes, which supports that amborellales and nymphaeales are sister lineages that successively diverged from other extant angiosperms. a nymphaeales- specific whole genome duplication was found by genomic collinearity and synonymous substitution analyses, possibly shared by the two families of nymphaeales — nymphaeaceae and cabombaceae. whole genome duplication and tandem duplication generated about mads-box genes retained in the n.colorata genome, including the abce homeotic genes that determine floral organ identity. most of the abce genes showed expression profiles consistent with their roles in floral organ patterning. however, overall, they exhibit a broader range of expression in floral organs than their homologues in eudicot systems, representing an ancient form of abce model for flower development. this expression model is consistent with the uniquely high similarities between sepals and petals in nymphaeales species. n. colorata flowers have floral scents attractive to insect pollinators. the researchers identified abundant terpene synthase genes and nymphaeales-specific sabath methyltransferases in the waterlily genome, which may catalyse the synthesis of these volatile compounds. moreover, an anthocyanidin synthase and a delphinidin modification enzyme were found to catalyse the biosynthesis of anthocyanidin pigment that confers the attractive blue petal colour. finally, genes related to biotic and abiotic stress responses expanded in water lilies, possibly leading to the wide adaptability of this lineage. jun lyu published online: february https://doi.org/ . /s - - - credit: image courtesy of tianlong zhu nature plants | vol | february | | www.nature.com/natureplants http://doi.org/dg mailto: https://doi.org/ . /s - - - http://www.nature.com/natureplants encoding beauty microsoft word - s&f_ .docx s&f_n. _ massimiliano fraldi the mechanical beauty of hierarchically organized living structures . introduction . from designing of anti‐seismic macro‐structures to the tuning of micro‐earthquakes to selective destroy tumor cells: oncology meets engineering . fuzzy boundaries between living and non‐living worlds delineated by the phase‐transition paradigm in cells: a philosophic challenge? . competition and cooperation in biomechanics: engineering meets behavioral sciences . conclusions abstract: by traveling through the inner structure of biological tissues, for instance by means of a scanning or a transmission electron microscope, unexpectedly exact geometries and symmetries in the form of perfect lattices, honeycomb networks, helical macromolecules and polyhedral shapes resulting from minimal surfaces can be observed. furthermore, by exploring cells and tissues at meso‐, micro‐ and nano‐scale levels, one discovers that self‐ similarity and hierarchy replicate that geometrical order and surprisingly characterize all the biological architectures, in this way de facto governing the key biomechanical functions and biochemical signaling at the basis of the life. dossier massimiliano fraldi, the mechanical beauty we must, incidentally, make it clear from the beginning that if a thing is not a science, it is not necessarily bad. for example, love is not a science. so, if something is said not to be a science, it does not mean that there is something wrong with it; it just means that it is not a science. richard p. feynman, lectures on physics the objective of science after all is not to add layers of interpretational complexity with each discovery, but to collapse layers of apparent complexity into a few simple governing principles; parsimony should prevail. gerald h. pollack, cells, gels and the engines of life . introduction by traveling through the inner structure of biological tissues, for instance by means of a scanning or a transmission electron microscope, unexpectedly exact geometries and symmetries in the form of perfect lattices, honeycomb networks, helical macromolecules and polyhedral shapes resulting from minimal surfaces can be observed. furthermore, by exploring cells and tissues at meso‐, micro‐ and nano‐scale levels, one discovers that self‐similarity and hierarchy replicate that geometrical order and surprisingly characterize all the biological architectures, in this way de facto governing the key biomechanical functions and biochemical signaling at the basis of the life. the apparent extreme shape minimalism that nature exhibits when analyzed at sub‐macroscopic level is therefore deceptive and thrilling at the same time: the geometrical neatness is indeed often counterbalanced by extremely complex functional relationships and multi‐physical interactions – occurring over different spatial and time scales – which force who tries to interpret the dynamics of biological systems through mathematical models to somewhat reconsider matters that he/she previously deemed foundations and then to respond to new fundamental questions raised by counterintuitive events and seeming paradoxes, trouncing the cultural barriers that traditionally separate the disciplines – and often obscure the beauty. in what follows, i collect some considerations – the most part of which are explicitly referred to recent results and current s&f_n. _ studies i’m working on – whose common denominator resides in the fact that the related themes (and related open issues), somehow, do not inhabit one the reassuring houses built up with thick walls by the several disciplinary areas, but most likely can be found wandering in the gardens of those houses – or skipping fences. . from designing of anti‐seismic macro‐structures to the tuning of micro‐earthquakes to selective destroy tumor cells: oncology meets engineering an earthquake is an event – sometimes catastrophic and often unforeseeable – due to a sudden release of energy in the earth’s crust that produces seismic waves: at the earth’s surface it manifests itself by shaking, fracture and displacement of the ground, and sometimes can accompany (or may trigger) landslides and volcanic activities. at the “macroscopic scale” – the scale at which we are all familiar with earthquakes – the task for civil engineers is to design anti‐seismic structures and systems able to dissipate energy for protecting existing buildings and make constructions resistant to seismic attacks. at the “microscopic scale”, say the scale of human cells, the cytoskeleton (csk) – a complex network of hierarchically organized polymers involving actin filaments, microtubules and a group of accessory polymers collectively known as intermediate filaments – constitutes the bearing structure of the cell. contractile microfilaments in fact generate and distribute tension to all cell csk filament systems, locally resisting compression when either cross‐linked within large bundles or contracted to their shortest length. microtubules also resist compression in cells, possibly because they are stabilized against buckling by lateral interconnections with pre‐stressed stiffened intermediate filaments. the csk network confers to the cell the skill to resist see: s. p. carey et al., mechanobiology of tumor invasion: engineering meets oncology, in «crit. rev. oncol. hematol.», , , , pp. ‐ . dossier massimiliano fraldi, the mechanical beauty deformation and its architecture, determined from self‐assembly‐ disassembling mechanisms dynamically regulated by the polymerization and depolymerization processes of actin filaments and microtubules continuously changing to find new optimal equilibrium configurations, controls the physical properties of the whole cell, mediating the linkage of the cell with the outside environment and modulating the process of recognition and conversion in chemical activities of mechanical stimuli (mechanotransduction). in this way, the cell csk structure governs short and long timescale changes in cellular behavior, reorganizing the network in response to externally applied forces, arranging and maintaining the integrity of intracellular compartments and in turn generating directed forces that guide cell shape changes necessary to carry out specific functions, such as crawling, spreading, division, contraction, migration, adhesion and invasion. from the theoretical point of view, the tensegrity paradigm – an original idea by donald ingber that interprets csk as an engineering pre‐tensioned micro‐structure – has demonstrated to provide a plausible explanation for some csk stiffening responses, also allowing to understand how a local stress, induced by ligation of a subset of csk‐associated membrane receptors, can result in global modulation (immobilization) of receptors over the entire cell surface through the balancing of forces in cell structural elements characterized by a level of isometric tension, or pre‐stress, that guarantees the overall cell‐shape stability and long‐distance force transfer. if – as in deep documented by s. c cowin in his fundamental textbook tissue mechanics – the cell csk is a structure and force transmitting mechanisms play a crucial role in the biochemical regulation of cell activities, what about cell response to dynamic excitations? is it possible to exploit structural engineering s. c. cowin, s. b. doty, tissue mechanics, springer, . s&f_n. _ weapons to design new mechanically‐based strategies and approaches for stimulating/manipulating cells? it has been experimentally established, for example, that mechanical stress inhibits tumor growth, but overwhelming obstacles to the therapeutic translation in medicine of these laboratory results arise when moving from in‐ vitro to in‐vivo, because the same inhibition stress level generally kills (or affects) the normal tissues too, and selective loads are difficult to apply! very recently, however, experiments have demonstrated that csk mechanical properties of cells could be potentially relevant to discriminate among cancer and healthy cells, highlighting the possibility of measuring – independently from the cell lines – a significant difference in elastic stiffness between metastatic and normal cells, the former being about % softer than the latter. in principle – as in the case in which the seismic waves invest a town and selectively make collapsing the sole buildings whose oscillation frequencies match the earthquake ones (a phenomenon known as mechanical resonance) – differences in healthy and tumor cell stiffness could be exploited to design micro‐earthquakes, for example tuning ultrasounds in frequency and magnitude to selectively destroy cancer cells. literature already have shown that stem cells can be induced to renew themselves through mitotic division and differentiating into a specialized cell type, if stimulated in an opportune way. a signal of the potential for tumor therapy and other medical applications of a mechanical‐based stimulation can be also traced in very recent works, where the effects of ultrasounds treatment on adult resident cardiac primitive cells have been examined demonstrating the positive influence on both the proliferation and the differentiation of cardiomyocytes, smooth muscle and endothelial cells precursors. this is a ground on which all the sciences are called to pave the way – and break down the barriers. dossier massimiliano fraldi, the mechanical beauty . fuzzy boundaries between living and non‐living worlds delineated by the phase‐transition paradigm in cells: a philosophic challenge? an additional interesting perspective has been recently furnished by gerald h. pollack, professor of bioengineering at the university of washington in seattle and leader in the field of muscle contraction and motility, by exploring the possibility that the gel‐like nature of the cell cytoplasm – gel being a matrix of polymers to which water and ions cling – and the related phase‐ transition phenomena could explain the most part of the cell functions, say material transport, motility, division, secretion, communication, contraction and other cell activities, in this way suggesting an intriguing interpretation of the confines between living and non‐living structures which would ask for a philosophical thought. actually, by exploiting the pollack words, the relevance of phase transition for the cell is not difficult to envision, contraction arising out of shrinkage, motility arising out of shape change, transport arising out of solute separation, action potentials arising out of permeability change, etc. of the phase‐transition interpretational paradigm, the most attractive feature is constituted by the prodigious response that can be elicited by subtle environmental shift such a slight change of temperature or ph, such amplification being enhanced further in biological structures as a consequence of the high – and sometimes unexpected – degree of order and symmetry commonly exhibited by them. whereas synthetic gels are in fact typically built of tangled polymers with relatively modest order, cellular organelles such as the ciliary axoneme and muscle sarcomere exhibit extraordinary supramolecular order, with x‐ray diffraction patterns showing regularity down to about nanometer. with structural regularity, the triggering threshold should be the same everywhere, and the response should therefore be decisive and rapid. by following this line of – experimentally comforted – reasoning, symmetry and order surprisingly seem to rise to the fundamentals s&f_n. _ of the life machine, somehow in contrast with the intuitive collective imagination, which associates organic and living to geometrically muddled. actually, the phase‐transition model can be utilized to also explain dynamics of cells through the so‐called transition cooperativity concept, which moves from the above described high sensitivity of ordered microstructures to slight changes – or gradients – of signals and stimuli. cooperativity generally arises out of competition between two or more forces, in the case of polymer strands the competing forces arising from the polymer’s attraction to water and to polymer. cooperative propagation mimics (or is?) a living behavior and in polymers may be observed – or realized – by exploiting the mechanism based on the “association‐induction” hypothesis: in a carbon chain such as that of a protein or polymer, local structural change produces an electron‐cloud shift, which induces a similar cloud shift and structural change in the next region [...] thus, the transition propagates along the polymer [...] analogously to what happens when a magnet is brought near an array of nails loosely strung to one another with bits of string [...]. the first nail is magnetized, which magnetizes the second, etc., until many or all nails are recruited into the new configuration. in such a way the structural change propagates. these cooperative mechanisms and the underlying phase‐transition hypothesis thus forces us to re‐think the definition of life, cellular processes and cells themselves operating – and living – by obeying the same physical and chemical principles that govern ordinary non‐biological systems. as defiantly postulated by pollack, [...] presupposing similar principles operating on either side of the boundary provides an appropriately seamless transition between living and non‐living [...] the notion of continuity across the living – non‐ living boundary seems logical because the boundary is fuzzy. is the seed living? what about the virus? – but one might add the question: what about life, and death!? . competition and cooperation in biomechanics: engineering meets behavioral sciences modeling living tissues implies a significant effort to gain insights into the basic understanding of the dynamics which cells, dossier massimiliano fraldi, the mechanical beauty tissues and organs obey. this in turn forces to think how to catch the essential mechanisms governing growth, remodeling and morphogenesis at the different scale levels, open‐mindedness being the fundamental weapon and the precondition for this exploration. as a result of growing interest of the biomedical research with respect the new scenarios recently opened in the field of therapy and diagnosis of human diseases by the designing of drug delivery systems as well as by the applications of tissue engineering and biomaterials, the mechanical properties and the underlying hierarchical organization of living tissues represent to date issues of primary interest in biomechanics, cancer‐related topics being obviously at the center of the interest. cancer can be viewed as a disease involving irreversible genomic alterations affecting intrinsic cellular cycles. these genomic alterations act in combination with the modification of the environmental conditions defined by immune response, matrix metabolism and stiffness, mechanical and biochemical gradients. with the aim of predicting cancer fate, the growth of solid tumors can be treated physically as a mechanical process according to which a heterogeneous tissue expands within a surrounding medium. tumor expansion is controlled by some internal driving stresses, which are counterbalanced by mechanical resistance provided by the surrounding environment. internal stresses are mostly generated by cells proliferation dynamics, which is influenced by the diffusion of nutrients within the tumor. this implies that the physical forces pushing the tumor ahead do not involve the sole surface tension and the pressure of the surrounding medium, but also the explicit active cellular forces deputy in the momentum balance that, in turn, retrospectively activate mechanosensitive cellular processes. with the aim to gain some new insights into the basic understanding of the complex machine of the host‐tumor interaction in growing solid tumors, heterogeneous poroelastic models of tumor s&f_n. _ spheroids can be helpfully constructed taking into account the mechanically activated stress fields, fluid pressure and nutrient walkway all coupled with spatially inhomogeneous and time‐varying bulk growth. actually, the growth is a result of competitive‐cooperative dynamics occurring at the microscopic scale level among healthy cells, cancer cells and extra‐cellular matrix (ecm) and – in principle – should not be assumed a‐priori. nevertheless, these dynamics are generally neglected in engineering models, as a consequence of both the difficulty of mathematically describing them with sufficient accuracy and the problems arising from the coupling of competition equations with the mechanical ones. to try to overcome these limits – limits which significantly reduce the aptitude of the mathematical models to predict the destiny of tumor masses – the idea we are working on at the university of napoli is to macroscopically model the dynamics occurring at microscopic scales by introducing ad hoc non‐linear lotka/volterra‐like equations, extensively utilized to describe ecological systems as well as several population dynamics which involve psychological and collective behaviors of social communities. the basic idea is that cancer and healthy cell species do not compete directly, as it would happen in a so‐called pure predator‐ prey logic, but fight to contend the common resources occupying the shared environment. the common resources are thus constituted by the available fluid content supposed to be saturated of nutrients, the environment being simply represented by the space that cells can inhabit at a certain time during growth and proliferation processes. the introduction of this transitive effect, that permeates through the system and enriches previously proposed poroelastic models, seems to well mimics the actual competition among cell species, by also reproducing the experimentally observed coupled dynamics in which the presence of dossier massimiliano fraldi, the mechanical beauty one species tends to somehow limit the development of the other. this mutual inhibition in turn modifies the intrinsic growth rates of the cell populations and leads to spatially inhomogeneous elastic and residual stresses as well as non‐uniform interstitial fluid pressure distributions within the tumor spheroid. although some features depending on the direct competition between cancer and healthy cells (such as the anti‐oncogenic potentials of some immune cells or the aggressiveness of pre‐malignant cells which become malignant as a result of mutation processes) remains to date still partially excluded, the choice of coupling mechanics with collective (social) behavioral schemes for cells seems to limpidly elucidate some key aspects at the basis of the dynamics of tumors, suggesting that – as stated by pollack – parsimony prevails when layers of apparent complexity collapse into a few simply governing principles . . conclusions in lectures on physics – an undisputed milestone in the field – richard feynman, one of the greatest physicists of all time known to have received the nobel prize in for his contributions to the theory of quantum electrodynamics, devoted a chapter of the book to the relation of physics to other disciplines. in those pages he originally – and somehow lightly – faced several themes and opened up on multidisciplinary horizons, by envisaging possible challenges in exploring memorizing mechanisms and nervous system brain cells and functions from both chemo‐physical and psychology standpoints, by additionally discussing at the end the «historical question» (so called, he said, for «lack of a better term»), a paradigm for highlighting an intrinsic difference between biology (and perhaps other human sciences) – interested in g. h. pollack, cells, gels and engines of life, ebner and sons publishers, seattle . s&f_n. _ the theory of evolution – and physics, that does not have questions about its laws like «how did they get that way?». at the end, he concluded with a phrase destined to be famous: a poet once said, “the whole universe is in a glass of wine”. we will probably never know in what sense he meant it [...]. but it is true that if we look at a glass of wine closely enough we see the entire universe. there are the things of physics: the twisting liquid which evaporates depending on the wind and weather, the reflection in the glass; and our imagination adds atoms. the glass is a distillation of the earth’s rocks, and in its composition we see the secrets of the universe’s age, and the evolution of stars. what strange array of chemicals are in the wine? how did they come to be? there are the ferments, the enzymes, the substrates, and the products. there in wine is found the great generalization; all life is fermentation. [...] if our small minds, for some convenience, divide this glass of wine, this universe, into parts – physics, biology, geology, astronomy, psychology, and so on – remember that nature does not know it! so let us put it all back together, not forgetting ultimately what it is for. let it give us one more final pleasure; drink it and forget it all! . however, feynman (and pierre louis maupertuis) should have been present to assist to a recent wonderful lecture at the university of napoli federico ii by sir anthony james leggett, professor of physics at the university of illinois at urbana‐champaign (he began studying literae humaniores at oxford) and nobel prize in physics in for his pioneering work on superfluidity. in that occasion professor leggett explained what he was dealing with, then illustrating how he had persuaded, on the basis of both experimental facts and theoretical (quantum‐mechanics based) arguments, that the arrow of time could – locally and temporarily – reverse! by putting aside, elegantly, any “usual” consideration on time machines (and avoiding to recall the film back to the future) he skipped mathematical and physical details and instead raised a new question, that is the necessity to admit that the induction principle (i.e. «past causes future, not vice versa») had to be violated. the implications for “free will”, determinism and anything today seems to be obvious – or natural – are enormous, but, perhaps, the r. p. feynman, lectures on physics, voll., addison wesley longman, boston, . dossier massimiliano fraldi, the mechanical beauty message contained in that slide was semantically even stronger: it is the most effective warning to bring together all forms of human thoughts given that, as stated by wittgenstein, the limits of my language means the limits of my world. massimiliano fraldi dipartimento di strutture per l'ingegneria e l'architettura (dist) e centro di ricerca interdipartimentale sui biomateriali (crib) – scuola politecnica – università degli studi di napoli federico ii fraldi@unina.it revista internacional de culturas y literaturas, junio issn: - d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . recibido: / / - aceptado: / / angela articoni universidad de foggia lo schermo tra le pagine. per una la rilettura de la bella addormentata nel bosco, genesi e metamorfosi di una fiaba screen into the pages. reviewing the sleeping beauty, gene-sis and metamorphosis of a fairy tale riassunto: la metafora della “bella addormentata”, archetipo del femminile che si risveglia solo con “il bacio del vero amore”, inteso come bisogno imprescindibile della figura maschile per la realizzazione del proprio sé, va mutando attraverso il rapido evolversi delle trasformazioni sociali e culturali. i film maleficent e la belle endormie ribadiscono il valore del femminile all’interno delle narrazioni simboliche. parole chiave: letteratura per l’infanzia, la bella addormentata, fiabe, cinema. abstract: the metaphor of “sleeping beauty”, the archetypal female that only wakes up with “love’s true kiss”, understood as essential of the male figure needed for the realization of one’s self, it is changing through the rapidly changing social and cultural transforma-tions. the movie maleficent and la belle endormie reaffirm the value of the feminine within the symbolic narratives. key word: children’s literature, sleeping beauty, fairy tales, cinema. http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . introduzione la fiaba antica si è innovata non solo nell’adozione dei potenti mezzi espressivi e figurativi attuali, capaci di evocare con efficacia un mondo favoloso, ma anche e soprattutto nello scavare fra conscio e inconscio e nel mostrare l’animo dei protagonisti sofferente, complesso, assetato di relazione, soggetto a evoluzione e sviluppo. il racconto che tutti padroneggiamo, e che ha già tante origini e versioni diverse se pure con connotazioni simili, viene riproposto dal cinema con diverse angolazioni: nel cartone animato del (geronimi, et al.), c’è la visione rosea della disney del bene che trionfa sul male, malefica, la strega cattiva che soccombe, la principessa aurora sposa il principe e tutti vissero felici e contenti. maleficent (stromberg, ), invece, adotta il punto di vista della strega della quale vengono mostrati moti interiori e un’intensa evoluzione psicologica: non più icona del male ma personaggio articolato, con un dinamismo interiore caratterizzato da vari atteggiamenti umani, a cominciare dalla dualità etica e comportamentale bene/male che nelle fiabe viene di solito mostrata in personaggi opposti, incarnazioni stereotipate e astratte di attitudini e modalità relazionali. inoltre rivela come il male possa essere reazione a un torto subito e l’odio sia amore cambiato di segno, quasi a significare che il modo d’essere originario sia quello positivo e il male conseguenza di interventi aggressivi, creazione umana sconosciuta allo stato di natura. la belle endormie (breillat, ) è una riflessione sulle identità di genere e sui loro confini, sul conflitto tra natura e cultura, e quindi tra destino e scelta (l’identità come imposizione o come costruzione individuale), sul trascorrere del tempo (gli orologi sono spesso presenti nelle inquadrature), sull’amore, sulla formazione e sui riti che scandiscono il passaggio dall’infanzia all’età adulta. le fiabe, afferma marie-louise von franz, racchiudono un tesoro di saggezza naturale e profonda ed «esprimono contenuti inconsci per i quali la mentalità collettiva non possiede un linguaggio» ( : ). il racconto di rosaspina (grimm, j. & w., : - ) ovvero de la bella addormentata (perrault, : - ), è l’occasione per sostenere la rinascita creativa della donna, quanto il motivo universale della “liberazione della principessa” o, come nel caso di demetra e kore, del ricongiungimento dell’aspetto materno con il sé fanciullesco e creativo, il risveglio della coscienza e dei modi atti a conseguirla. le fiabe sostengono e incoraggiano il processo di individuazione della donna ( : e segg). per bruno bettelheim la bella addormentata nel bosco è una narrazione che ribadisce la necessità di una prolungata e riflessiva concentrazione su se stessi. lo psicanalista asserisce che sia i maschi sia le femmine, durante il periodo dell’adolescenza, hanno bisogno di periodi di quiete, quasi di passività, oltre che di movimento, affinché si http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . realizzino condizioni propizie per il loro armonioso sviluppo: un lungo periodo di quiescenza, di riflessione e di introspezione può aiutare il bambino e la bambina a crescere e ad affrontare il futuro in modo cosciente e giudizioso ( : e segg). le mille identità di una fiaba marie-louise tenèze, portando a termine una ricerca iniziata da paul delarue, stila un catalogo che analizza centinaia di raccolte, le conte populaire français ( ), e prende in considerazione solo quattro versioni della fiaba: troila e zellandina - dal iii libro di perceforest - la novella catalana di frère-de joie, soeur-de-plasir, del xiv secolo, il pentamerone di basile, edito fra il e il (ma che potrebbe essere stato scritto su ispirazione della versione italiana del perceforest del ), e ovviamente la bella addormentata nel bosco di perrault, la cui prima versione, manoscritta, è del (soriano, : ). nel roman de perceforest, di uno scrittore anonimo del nord della francia, la protagonista figlia di un re, zellandina, è “amata” da un dio, esattamente dal dio marte. il protagonista maschile del romanzo francese si chiama troilo come il bellissimo figlio di ecuba e di priamo (in altre versioni considerato figlio di apollo), fratello di polissena. troilo è molto devoto a venere e a lei si rivolge per coronare il suo amore per zellandina, sua compagna di giochi fin dalla fanciullezza, con la quale si scambiò un anello come pegno d’amore. ma zellandina muore (cade in letargo) non appena tocca un fuso, una lisca le si conficca in un dito e il padre la rinchiude in una torre deponendola completamente nuda su un letto. quando troilo viene a conoscenza della “malattia” che ha colpito la sua amata, con l’aiuto di venere e di zeffiro, un demone- folletto, scala la torre e, trovandosi davanti la sua bella nuda sul talamo, si unisce a lei stuzzicato e “infuocato” da venere. verrà concepito un bambino e sarà proprio la nascita del figlio a provocare il risveglio di zellandina, poiché, venendo al mondo, il piccolo rimuoverà il filo di lino che provocava il sonno della madre (franci, zago, : - ). la versione italiana, troilo e zelanda riflette il perbenismo che pervade la seconda metà del cinquecento: il testo originale conteneva troppe allusioni erotiche e la traduzione elimina le parti più scabrose. rimossa la figura di venere, il momento della esistono quattro manoscritti, due dei quali, incompleti, sono alla biblioteca nazionale di parigi: ms. fr. - , libri i, ii, iii, v. ms. fr. - , libri i e iv. un esemplare completo è custodito alla bibliothèque de l’arsenal di parigi: ms. - . il british museum di londra possiede i volumi i, ii, iii (rpyal e v, e iii, e . franci, g. - zago, e., la bella addormentata. genesi e metamorfosi di una fiaba, bari, dedalo, , p. . dal parsaforesto, trad. italiana del roman de perceforest, cap. e del libro iii, venezia, tipografia di michele tramezzino, , visionabile interamente su gallica, in gallica.bnf.fr/ark:/ /bpt k . franci, g. - zago, e., la bella addormentata, cit., p. . http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . deflorazione viene descritto pudicamente: «il cavaliere si mise in letto e la damigella venne a perdere il suo nome chiamandosi donna» ( : ). frère-de joie, soeur-de-plasir (thiolier méjean, ) ha lo stesso impianto stilistico del roman de perceforest: “sorella di piacere” muore di colpo e il padre, che non si rassegna alla morte della bellissima figlia, fa costruire un castello incantato dove la depone. il principe “fratello di gioia” trova il modo di giungere fino a lei a cui si congiunge lasciandola incinta e ripartendo subito dopo per cercare la medicina che la farà risvegliare. la principessa, nel frattempo, partorisce «senza dolore e senza pericolo» (franci, zago, : ). con l’aiuto di un uccello parlante la ragazza magicamente rivive e allibita scopre che non solo ha perso la verginità, ma ora ha un figlio illegittimo. estremamente interessante e degne di nota le proteste della giovane donna al pennuto che le racconta tutto ciò che è avvenuto con il principe: […] egli ebbe l’audacia di prendermi senza il mio consenso. se egli avesse saputo aspettare che io gli dessi la gioia del mio amore, e che io facessi la mia scelta, lo considererei nobile. non v’è al mondo donna tanto spregevole che la si possa toccare o prendere qualcosa di suo senza chiedergliene il permesso: le cose prese con la forza non hanno valore. […] chi tocca una donna senza chiedergliene il permesso non è mai stato considerato né nobile, né valente. e nessuna donna è degna e nobile se si lascia toccare senza averlo permesso ( : ). in sole, luna e talia da lu cunto de li cunti ovvero lo trattenemiento de peccerille di giambattista basile ( : - ), alla figlia di un gran signore di nome talia, sapienti e indovini provenienti da ogni parte del regno predicono il destino: la bambina avrebbe corso un pericolo mortale a causa di una lisca di lino. ovviamente il padre ordinò che nel suo palazzo non entrasse lino, né canapa, né nulla di simile, per sfuggire a questa sciagura. ma, essenno talia grannecella e stanno a la fenestra, vedde passare na vecchia che filava; e, perché n’aveva visto mai conocchia né fuso e piacennole assai chello rocioliare che faceva, le venne tanta curiositate che la fece saglire ‘ncoppa, e, pigliato la rocca ‘mano, commenzaie a stennere lo filo, ma pe desgrazia, trasutole na resta de lino dintro l’ogna, cadette morta ‘n terra ( : ). anche nella fiaba di basile la bella addormentata talia è vittima, durante il sortilegio, dello stupro di un re: all’utemo arrivaie a la cammara dove steva talia comme ‘ncantata, che vista da lo re, credennose che dormesse, la chiammaie; ma, non revenenno pe quanto facesse e gridasse e pigliato de caudo de chelle bellezze, portatola de pesole a no lietto ne couze li frutte d’ammore e, lassatola corcata, se ne tornaie a lo regno suio, dove non se allecordaie pe no piezzo de chesto che l’era socciesso ( : ). http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . perrault in la belle au bois dormant, la bella addormentata nel bosco (perrault, : - ), riprende i temi dalla storia di basile sole, luna e talia ma li addolcisce molto. essendo la dedicataria dell’opera la nipote del re di francia e avendola data alle stampe rivolgendosi a un pubblico borghese, elimina i tratti perturbanti e scabrosi per enfatizzare virtù morali quali la pazienza e la passività della donna e «l’incantesimo finisce non appena il principe si mette in ginocchio di fronte a lei» (soriano, : - ). rosaspina dei f.lli grimm ( : - ) è la versione più nota e più breve, che si conclude con le nozze del principe con la principessa, risvegliata da un casto bacio del suo futuro sposo. «di tutte le versioni [...] quella dei fratelli grimm è indubbiamente la più vicina all’idea che tutti più o meno abbiamo della fiaba classica: è semplice, chiara, diretta, assolutamente priva di conflitti psicologici, al di fuori del tempo, dello spazio e della realtà» (franci, zago, : ). nella narrazione dei grimm la principessa è chiamata rosaspina (dornröschen) con riferimento ai cespugli di rovi che circondano il castello durante il suo sonno centenario, rendendolo irraggiungibile; questo nome le viene attribuito non dai genitori, ma dal popolo, quando, con il passare degli anni, ella si trasforma in una figura leggendaria. tale appellativo sarà utilizzato nel film disney, nella parte (del tutto inesistente nelle fiaba tradizionale) in cui aurora è nascosta nel bosco dalle fate. sleeping beauty e maleficent: dal film d’animazione al live action malefica, la strega più accattivante e terribile delle fiabe disney, approda al cinema in carne e ossa, interpretata da angelina jolie. il film la estrapola da uno dei cartoni animati più amati della disney, sleeping beauty (geronimi, et al., ) ispirato alla fiaba di perrault, la bella addormentata nel bosco ( : - ) e a rosaspina dei grimm ( : - ), anche se con molte differenze: dal nome della principessa, aurora, che nella versione perraultiana è quello della figlia, al numero delle fate, solo tre (perrault ne enumera otto, grimm addirittura tredici), alla presenza costante della strega malefica. anche nel film animato la sua malvagità è scatenata dal non essere stata invitata al battesimo della piccola principessa, futura bella addormentata, mancanza che le farà lanciare la maledizione del fuso e del sonno senza fine. all’epoca il cartoon non ottenne lo stesso successo di pubblico dei precedenti lungometraggi, fu «un disastro commerciale in technirama costato l’astronomica cifra di sei milioni di dollari» (Ėjzenštejn, : ). per trent’anni fu l’ultimo adattamento di una fiaba prodotto dalla disney, anche a causa dell’accoglienza discordante della critica, e lo studio ritornò al genere solo dopo la morte di walt disney, con l’uscita de la sirenetta (clements, john musker, ), fiaba celeberrima di h.c. andersen, di http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . cui è previsto anche un live action: quella del remake con veri attori è una prassi ormai consolidata in casa disney. il remake viene equiparato alla leggenda, un racconto straordinario che è sedimentato nella memoria e perciò provoca emozioni, inoltre accontenta la nostra voglia di rassicurazione perché, come il bambino che costruisce il suo io attraverso le storie di cui conosce ogni particolare, ma le vuole ascoltare ancora e ancora, siamo ben felici di vedere e rivedere le stesse immagini. ecco perché, fin dalla nascita del cinema, si saccheggiarono i classici della letteratura e del teatro che incontrarono, immancabilmente, il gradimento del pubblico (articoni, : - ). secondo la critica malefica è il personaggio caratterizzante del cartoon e forse una delle “cattive” disney meglio definite: domina ogni scena in cui appare. sembrerebbe la mutazione negativa della strega grimilde di biancaneve (hand, ) ma, a differenza della sua antenata, l’antagonista della principessa aurora straborda di fascino maligno, a partire dalla conformazione fisica: tanto è morbido e sinuoso il segno per la dolce protagonista aurora, così è stilizzato e spigoloso quello della villain maleficent. inoltre l’animatore marc davis creò per “la fata cattiva” un look impeccabile curando sia il fisico sia l’abbigliamento, sofisticato, non trasandato e non da classica strega: nella sua ricerca stilistica, tra opere d’arte del medioevo, si imbatté nell’immagine di una religiosa vestita in modo elegantemente diabolico con mantelle fluide e abiti simili a fiamme. si concentrò proprio sulla comparsa del fuoco - propose un abito in nero e rosso, che poi venne tramutato in nero e lavanda - la incoronò con “le corna del diavolo” e le disegnò alfine anche ali di pipistrello (seastrom, ). maleficent: da fata a strega maleficent (stromberg, ) è il nome della pellicola anche in italiano, mentre nel doppiaggio la strega è denominata malefica, come nel cartoon disney da cui è tratto il personaggio protagonista. la scelta appare filologicamente incongruente e illogica: in inglese l’aggettivo maleficent è inusitato e altisonante, ma viene subito riconosciuto il prefisso mal–, tipico di parole con connotazioni negative come malignant e malevolent. richiama inoltre l’aggettivo magnificent, “maestoso, imponente”, appropriato per un personaggio che incute soggezione (zimmer, ). probabilmente la disney ha fatto questa scelta per avere sia un fil rouge con il cartone, sia per un’internazionalizzazione del titolo, un nome unico globale per motivazioni di marketing. maleficent, che ha incassato ben milioni di dollari in tutto il mondo, indaga sul passato e sulle motivazioni che hanno trasformato la fata in strega, “costringendola” a lanciare il maleficio sulla figlia del re stefano. prima che malefica divenisse l’incarnazione femminea del male, cresceva serena e felice nella brughiera in totale armonia con tutte le altre creature magiche. come sottolinea la voce narrante del film http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . «non c’erano re o regine perché le creature si fidavano tra loro», e la foresta era un mondo giocoso e affascinante, con paesaggi emozionanti, un territorio incontaminato in cui le creature magiche prosperavano in libertà e in armonia con la natura che lei sorvolava con le sue immaginifiche ali nere, mentre nel regno vicino, quello degli uomini, regnava l’invidia e la sete di potere. conosce stefano, un ragazzino suo coetaneo, un umano, abbastanza curioso e impavido da spingersi nella brughiera per rubare una gemma. la loro amicizia, man mano che i due crescono, lascia il posto a un sentimento più profondo e, al sedicesimo anno di malefica, stefano le dona “il bacio del vero amore”. i conflitti tra umani e creature magiche si fanno però sempre più aspri, sfociando in una guerra, e la nostra fata è in prima linea a difendere la sua terra natia e i suoi abitanti. nel frattempo per stefano si presenta l’occasione di divenire re poiché l’anziano sovrano regnante emana un bando: chi riuscirà ad uccidere malefica verrà nominato suo successore. l’uomo, assente da tempo immemore dal mondo fatato e dalla donna che gli aveva donato il cuore per inseguire i suoi sogni di gloria e la sua brama di potere, ritorna nella brughiera e viene accolto con l’antico sentimento; addormenta la donna con un sonnifero e, accecato dall’ambizione, pur non avendo il coraggio di ucciderla, compie uno scempio e un delitto forse ancora peggiore: le taglia le ali e le porta con sé come testimonianza della sua vittoria. È un assalto altamente simbolico, con sfumature e rimandi all’atavica brutalità nei confronti delle donne, una mutilazione, una deturpazione fisica che ha uno specifico riferimento alla violenza di genere: il maschio è riuscita a ferirla, a sottometterla, a tarparle le ali, e non solo in senso metaforico. È una delle scene più penose della storia del cinema, soprattutto considerando la produzione disney: malefica è stata violata, oltraggiata, profanata, nel suo mondo, la sua splendida, rigogliosa ed accogliente brughiera, dall’unico umano in cui riponeva fiducia. il risveglio è amaro, drammatico, funesto: l’urlo straziante della fata è la voce di tutte le donne tradite. tale inconcepibile tradimento, avvenuto di notte, in un momento di intimità, è un atto di violenza così brutale da causare la perdita repentina dell’innocenza da parte di malefica e la lacerante presa di coscienza della distanza tra sogno e realtà, trasformando la brughiera in un regno analogo a quello degli uomini, dove la fata è la nuova, cupa sovrana. si veste di dolore e ghiaccia la foresta, sottomette gli esseri magici che ora la temono - non è più la loro protettrice ma la loro “padrona infittisce la selva che diviene nera ed impenetrabile e separa il suo mondo da quello degli umani. la protagonista è una fata dalle grandi ali, un simbolo che riemerge dalla preistoria e dalla più importante divinità che veniva adorata . anni a.c., la dea madre, o http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . dea uccello. la dea madre è ovviamente legata alla terra, alla sua capacità nutritiva e generativa, e alla natura, in quanto tale è dea sovrana degli animali e della vegetazione e come malefica del film, difende le sue creature e le ama profondamente. dea strettamente collegata a era, demetra e persefone considerate “dee vulnerabili” dallo studioso bolen ( : e segg.): le tre dee vulnerabili incarnano i ruoli tradizionali di moglie, madre e figlia. sono archetipi dell’orientamento al rapporto con il maschile, quelle dee cioè la cui identità, il cui benessere dipendono dalla presenza, nella loro vita, di un rapporto significativo; esprimono il bisogno di appartenenza attraverso il legame affettivo. sono vulnerabili nella misura in cui dipendono emotivamente dagli altri. nel mito venivano violentate, rapite, dominate o umiliate da divinità maschili (vallino, montaruli, : ) divinità sensibili e forse fragili ma che possono trasformarsi in personaggi oscuri e terrificanti per contrastare il potere, il tradimento e la malvagità, umana e divina. tali figure femminili arcaiche con questa duplice natura sono innumerevoli: ishtar, dea dell’amore, della fertilità e dell’erotismo, ma anche della guerra, nella mitologia babilonese; iside, anch’ella dea della maternità, della fertilità, ma temuta maga; atena, dea della sapienza, delle arti, ma anche della strategia militare; ecate, la dea della magia, degli incantesimi e degli spettri. forse la figura che maggiormente possiamo associare a malefica, è lilith, per gli antichi ebrei la prima moglie di adamo (quindi precedente ad eva) che fu ripudiata e cacciata via perché si rifiutò di obbedire al marito, che pretendeva di sottometterla, specie sessualmente, divenendo così uno spirito terribile, una signora dell’aria. “il bacio del vero amore” a fare le spese dell’ira della strega, la neonata aurora figlia di re stefano, sulla quale malefica scaglia la nota profezia, lievemente riadattata: la principessa crescerà in grazia e bellezza, amata da tutti coloro che la circondano. ma … prima che il sole tramonti sul suo sedicesimo compleanno, ella si pungerà il dito con il fuso di un arcolaio, e cadrà in un sonno mortale! solo il bacio del vero amore potrà spezzarlo e nessun potere ultraterreno potrà annullare il maleficio!. nella realtà e con il passare del tempo malefica si affeziona alla bambina, se ne prende cura, poiché le fate che se ne dovrebbero occupare sono totalmente incapaci. subisce una forte attrazione per la piccola, anche se non vuole ammetterlo, la chiama “bestiolina”, prova a spaventarla, ma la bimba, dolce e fiduciosa, le sorride. la regina della brughiera lentamente diviene la sua guida silenziosa, la sua vera fata madrina e un sentimento nuovo va crescendo nel suo cuore, un amore che travalica l’odio e la rabbia che nutre nei confronti di re stefano: comprende che non è giusto usare aurora http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . come “merce di scambio” per il suo dolore. prova quindi ad annullare il suo sortilegio, ma invano: il maleficio si realizza. l’unica soluzione è “il bacio del vero amore” ma filippo, il principe costretto a baciare aurora, non riesce a svegliarla poiché non si può pretendere il vero amore da un ragazzo incontrato un paio di giorni prima. la disney cavalca l’onda della rottura degli stereotipi e della modernità e quando malefica, convinta di averla perduta per sempre, le bacia la fronte chiedendole perdono, aurora si risveglia. «non c’è amore più vero» - dice fosco . di quale amore stiamo parlando? di quello tra una madre, seppure “adottiva”, e una figlia? È questo il più vero? trascende qualsiasi rapporto tra un uomo e una donna? ci piace pensare che, in realtà, possa essere la riconciliazione del femminile avverso al femminile, e che si possa contare – ancora e sempre – sull’amore e sulla solidarietà tra donne: il patriarcato del regno degli uomini, guidato dalla cultura della paura, della rabbia e della violenza, può essere soppiantato dalla democrazia del matriarcato della brughiera solo quando malefica, la donna, abbandona le emozioni negative che la consumano (justice, : ). un percorso doloroso dopo la perdita dell’integrità e la lunga strada che deve percorrere per ritrovarla. ha lanciato un anatema soprattutto verso se stessa, convincendosi che il vero amore non esiste, e il suo sogno di amore infranto, proiettato sulla neonata, resterà tale finché non lascerà germogliare nuovamente il sentimento perduto: un amore più evoluto, più generativo, rivolto ad una creatura “altra da sé” e non un amore narciso. solo dopo averlo riconosciuto e accolto ritroverà la sua interezza, la sua compiutezza e perfezione, e quindi le sue ali per ritornare a volare. luci e ombre de la belle endormie iscritta in quello che viene definito “new french extremity”, catherine breillat è nota per i suoi discussi film incentrati sui conflitti e le rivalità tra i sessi, temi che compaiono anche nei suoi romanzi. lo sguardo che diviene voyeurismo, la provocazione e la trasgressione, sono caratteristiche del suo cinema, e la sessualità femminile, scrutata, analizzata, esplorata e nel contempo ricusata, disconosciuta e sofferta diviene strumento e tramite per un percorso intimo nell’inconscio, quasi come in una seduta psicanalitica perturbante. fin dall’inizio della sua carriera, breillat ha raffigurato la passione come fortemente legata alla sofferenza e ha considerato lerotismo come mezzo per esplorare i demoni delle donne e dei lati oscuri delle loro anime: attraverso i suoi film vuole affermare il valore della diversità, delle relazioni umane e del gioco della seduzione. fosco è il leale servitore di malefica, l’aiutante, che al suo comando può assumere diverse forme ed eseguire i suoi ordini. egli, dopo il taglio delle ali, sarà trasformato da corvo in uomo e diverrà le sue ali, i suoi occhi, la sua lunga mano. all’inizio è una figura maschile dominata dal femminile, ma lentamente partecipa al dolore di malefica, la consiglia, la rimprovera e alla fine si intravede una collaborazione e un gioco affettuoso tra i due. http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . sia che scrivesse, recitasse o dirigesse film, breillat diventò famosa come provocatrice, esplorando la sessualità delle donne e la vergogna che queste sono sempre state costrette a provare sotto lo sguardo maschile. quasi tutti i suoi romanzi e film principali sono ritratti sfrontati di relazioni sessuali che possono essere descritte al meglio come nodi e conflitti intensi in cui alcune donne cercano di guadagnare un senso del sé scoprendo e al tempo stesso reclamando il proprio desiderio sessuale (zipes, : - ). dopo la finissima e sofisticata rivisitazione dell’antesignano di tutti i mariti violenti con la pellicola barbe bleue (breillat, ), da alcuni considerata come la miglior mise- en-scène di the bloody chamber ( ) di angela carter, come decostruzione e diritto alla variazione, che la trascrizione delle fiabe orali ha cancellato, breillat - in effetti molto affine allo spirito malizioso e poco convenzionale della compianta scrittrice britannica - continua la sua esplorazione del mondo delle fiabe con la belle endormie (breillat, ), tra meraviglioso e crudeltà, questa volta volgendo lo sguardo decisamente verso l’infanzia e la sua crescita emotiva oltre che fisica. rispetto a barbe bleue, lo sguardo filmico verso les contes di perrault cambia radicalmente poiché breillat non si accontenta di rifrangere il racconto attraverso il prisma del suo temperamento: usa invece il pretesto della narrazione per bambini come una sorta di camouflage per compiere uno dei suoi salti più audaci nell’astrazione. la regista asserisce che la belle endormie è un lavoro diverso poiché desiderava che la giovane protagonista vivesse innumerevoli esperienze, come tante vite, «attraverso un percorso unico ed intimo racchiuso in un’unica esistenza, alternandola con un amore difficile, a metà tra la maturità dell’età adulta e la fanciullezza» (tarasco, ). pellicola talmente fuori dagli schemi che è stata oggetto di giudizi anche feroci da parte della critica, soprattutto maschile : jack zipes, per esempio, che ha apprezzato il remake barbe bleue ( : - ), ha affermato che breillat «pecca di pretenziosità e cedimenti al mercato» e ha addirittura definito il film un pastiche ( : ) . queste alcune tra le critiche al film che nel ha aperto la sezione orizzonti alla mostra internazionale d’arte cinematografica di venezia: «pedante, [...] un’opera che vorrebbe essere fem- minista, ma che risulta complessivamente minore, senza ritmo e frammentata. una delle tante cose, che in un festival finisco per non lasciare traccia» (albanese, ); «[...] un’opera minore, meno pregnante e provocatoria di altri suoi lavori. [...] la tediosità di una storia fatta perlopiù di dialoghi nei quali i personaggi pronunciano, con tono inespressivo, frasi sentenziose tutt’al più, i fans “senza se e senza ma” della regista [...] troveranno un aggiornamento sui temi e sulle “ossessioni” tipiche del suo cinema una delle tante cose, che in un festival finisco per non lasciare traccia» (vignati, ); «il problema è che è il cinema stesso della breillat a risultare ormai spogliato di qualsiasi appeal. il suo voler intrecciare il limite estremo di immaginario (la fiaba) e il limite estremo del “concreto” (il sesso), e il suo voler individuare il punto in cui dal primo si passa all’altro abbandonando un’infan- zia notoriamente tutt’altro che asessuata, proprio non funziona» (grosoli, ). «breillat cerca di mutare le fiabe di perrault e andersen in un racconto di formazione (con la be- lla addormentata che entra ed esce da prevedibili esperienze), scimmiottando la storia di andersen e infilando qualche corposa scena di sesso in un film che complessivamente non va da nessuna parte. È un lavoro che riduce il femminismo a luoghi comuni» (zipes, : ). http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . riteniamo invece che, effetti speciali e rimandi al cinema fantastico e irreale di georges méliès e alla versatilità, originalità e capacità espressiva di jean cocteau, allusioni erudite alla pittura classica, tracce, richiami e prestiti da alice nel paese delle meraviglie di lewis carroll ( : - ) e soprattutto da la regina delle nevi di h.c. andersen ( : - ), ne fanno un racconto in cui «l’amore sognato» perde l’aura luminosa e celestiale e si mostra in tutta la sua aspra realtà, il linguaggio filmico spazia dall’onirico al carnale pur mantenendo una forte carica estetica, e innocenza e moralità vengono osservate attraverso l’ordito della tela fiabesca. pensiamo sia importante, ancora una volta, rimarcare le parole dell’autrice, secondo la quale: questa è la storia di una giovane ragazza che ricrea il suo mondo. l’infanzia è un limbo lungo e difficile che precede la gioventù. questa giovane ragazza cresce e diventa un’adolescente che crede di sapere tutto della vita. ma la vita non è una fiaba, e l’amore durante l’adolescenza è come un maternità precoce, che conduce a un altro stato di vita. e si ritorna alla vita reale. non è più una favola, ma il racconto di una vita che sta per iniziare (mascagni, ). la belle endormie è dunque una riflessione sull’identità di genere e sui suoi confini, sul contrasto tra natura e cultura, e tra destino e scelta (l’identità come imposizione o come costruzione individuale), sul trascorrere del tempo, sulla formazione e sui riti che scandiscono il passaggio dall’infanzia all’età adulta e, ovviamente, sull’amore: possibilità di liberare più testi nello stesso testo, più significati dallo stesso significante, un frame dentro un altro frame, come una sorprendente matrioska. la bella addormentata come metafora di crescita c’era una volta, in un passato e in un luogo indefinito, come sempre nelle fiabe, un castello dove nasce una bambina, anastasia. la fata carabosse taglia il cordone ombelicale della neonata, mentre arrivano in ritardo tre giovani fate trafelate, troppo tardi per carabosse che lancia il maleficio, del quale però non si comprende il motivo: al compimento del sesto anno di vita la bambina si pungerà la mano e morirà. le giovani scoppiano a piangere! il loro ritardo non meritava una tale punizione. ora dovranno mitigare l’incantesimo fatale, scongiurare questa orrenda predizione: invece di morire anastasia si addormenterà a sei anni per un secolo e si risveglierà sedicenne (anticipandolo ai sei, anziché ai sedici anni, per superare la noia dell’infanzia); ma nella varie versioni della fiaba il nome della fata cattiva non è specificato. carabosse è il nome che ivan vsevolozhsky le dà nel nel libretto scritto per un nuovo balletto, basato sulla fiaba di charles perrault e musicato da Čajkovskij e diviene nel tempo uno dei nomi attribuito alla fata ma- ligna. http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . dormire per cento anni sarebbe monotono se non le concedessero di girovagare in lungo e in largo in sogno durante questo periodo di sonno . prima di essere immersa nelle sue visioni oniriche, assistiamo ai primi anni di vita della bambina che si rifiuta di dormire (ha decine e decine di sveglie intorno al letto, premessa dell’importanza del concetto del tempo nel film) e si sente confusa sulla sua sessualità: insiste per essere chiamata vladimir e in una delle sue curiose escursioni nel dizionario incontra il termine “ermafrodita”. con il sonno e il sogno indotti, la piccola entra in un nuovo mondo, attraverso un sinistro passaggio sotterraneo, con echi di avventura di alice, che porta in un ambiente rurale nel quale viene “adottata” da una famiglia modesta: qui si confronterà con la prima figura maschile, peter, un ragazzino incontrato per caso e velocemente perduto, il futuro principe che dovrebbe risvegliare la bella dormiente. peter viene portato via dalla regina delle nevi e così principia un percorso in cui lasciare alle spalle l’infanzia, mettere in discussione la propria identità e un onirico meticciamento tra fiabe: catherine breillat promette la bella addormentata e invece, a sorpresa, dopo l’incipit, ci ritroviamo in un “mondo altro”, un racconto vergato da più linee testuali, un fantastico viaggio nel tempo che ripercorre i luoghi de la regina delle nevi, ma che non disdegna trovate felliniane nella stuttura dei personaggi come il nano in uniforme, la domestica carceriera punk, il principe e la principessa albini, la tribù dei briganti, la barbona della lapponia. alla fine delle mille peripezie affrontate per ritrovare peter, anastasia mangia da una cespuglio alcune bacche, pur sapendo che sono velenose: non si può morire in un sogno; ma quei chicchi rossi segneranno la morte dell’infanzia e la nostra bambina si ritroverà sedicenne, coperta di polvere, a svegliarsi nel palazzo che apparteneva alla sua famiglia e accanto al suo letto un bel giovane di nome johan, non il principe azzurro, ma un ragazzo vestito di nero: il sogno di anastasia è finito? dopo un primo timido approccio, johan la lascia sola e inaspettatamente giunge la sua amica brigante, ormai cresciuta, con la quale vive la sua prima esperienza sessuale adulta. viene lecito domandarsi se per caso la nostra protagonista stia ancora sognando, ma a questo interrogativo non è facile rispondere poiché breillat non altera in modo significativo il flusso di fantasia e realismo, del soggettivo e dell’oggettivo, dopo che anastasia ha aperto gli occhi. ritorna johan e proseguono una timida ma intensa esplorazione pre-sessuale: la giovane si è risvegliata in un abito vecchio stile, con decine di bottoncini di chiusura, che permette al ragazzo di aprire piano piano, entro rigorosi limiti numerici. e sotto breillat recupera una frase del racconto di perrault che servirà a sostenere il discorso del sogno attraverso il film: «[...] possiamo presumere , anche se la storia non lo dice che la buona fata avesse provveduto a rallegrare il suo lungo sonno con sogni piacevoli» (perrault, ( ): ). http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . il vestito un corsetto, geniale e sosfisticata presenza narrativa che permette a breillat di sottolineare la chiusura dell’adolescente al sesso e, alla fine, la liberazione “fittizia” dal giogo dei lacci che assicurano il corpetto. sciolte una dopo l’altra le stringhe del vecchio scomodo bustino, il lungo vestito bianco dell’innocenza viene sostituito da minigonna e calze velate: la bellissima inquadratura finale mostra una calza smagliata della ragazza e un graffio ancora sanguinante sulla schiena di lui. niente più fiabe, siamo nel regno dei vivi, o dei morti: la conoscenza carnale tra uomo e donna, attraverso i secoli, è semplicemente una storia di violenze. e a chi ha chiesto a catherine breillat quante storie avessero contribuito alla messa in opera di la belle endormie penso che lo snodo cruciale della storia sia la scelta di “addormentarsi” all’età di anni e vivere da bambini per tutta la vita. vivere come un’eroina che passa la propria esistenza come un’esperienza. quella della “mia” anastasia è una fanciullezza illibata che si trascina fino a sedici anni, non solo perché vergine sessualmente ma perché vergine nella vita e nei sentimenti. la protagonista è una combattente ed è qui che sta lo charme della favola (tarasco, ). la belle endormie non è una fiaba, ma il racconto di una vita che inizia, anzi due, perchè anastasia è incinta. conclusione la fiaba è un medium rassicurante e spensierato per riflettere sul mondo e proietta all’esterno, in termini assoluti, le paure, i desideri, i rancori, le emozioni più pure e quelle più torbide. le storie colonizzate e trasformate dal cinema hanno forse poco a che fare con i vari e strambi personaggi che la tradizione popolare ha saputo creare, pur ambientandosi in luoghi sperduti e pieni di magia, ma riguardano tutti noi, nessuno escluso, in quanto persone, in quanto esseri umani. sono “romanzi di formazione” in forma visiva, che incosciamente ci guidano verso una maggiore consapevolezza della nostra vita e quotidianità. se si esclude il cartone animato che propone una bella addormentata profondamente americana, una dolce fanciulla bionda che corrisponde all’ideale femminile promosso in america nei primi anni postbellici, divenuto il bersaglio preferito delle polemiche sociologiche e psicologiche e che diede spunto a innumerevoli parodie polemiche - fra tutte le graffianti versioni in chiave femminista di angela carter - le riscritture e le reinterpretazioni che abbiamo analizzato sono metafore di una crescita femminile “cosciente” complessa e non banale. in maleficent non si ripete lo schema narrativo che scinde il mondo femminile fra fate-madri-buone intrise di dolcezza, remissività e dedizione ad libitum e streghe ribelli- http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . crudeli-mortifere: nessuna univocità, nessun dualismo, la vita è molto più complessa. e quando le donne accolgono la loro complessità ed esprimono la loro rabbia per le offese subìte, senza restarne distrutte o distruggere, qualcosa di bello e di vitale si è salvato. così come breillat ne la belle endormie, un sogno dentro un sogno, attraverso l’immaginazione fiabesca esplora un’intera educazione sentimentale, dove la conoscenza carnale tra uomo e donna, attraverso i secoli, è semplicemente una storia di violenze, dove innocenza e moralità vengono osservate attraverso le increspature dell’ordito fiabesco, un gioco di slittamento del senso che racconta meglio di altre forme conosciute quello per niente divertente del desiderio e dell’orrore identitario dove il testo della tradizione riacquisisce tutto il potenziale combinatorio e aperto del racconto orale (faggi, ). riferimenti bibliografici andersen, c.h., “la regina delle nevi”, fiabe, milano, cde mondadori, , pp. - 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(a cura di), “sole, luna e talia, trattenemiento quinto de la ior- nata quinta”, lo cunto de li cunti, milano, garzanti, , pp. - . bettelheim, b., il mondo incantato. uso, importanza e significati psicoanalitici delle fiabe, milano, feltrinelli, . bolen, j.s., le dee dentro la donna. una nuova psicologia femminile, roma, astrolabio, . calvino, i., sulla fiaba, milano, mondadori, . carrol, l., “alice nel paese delle meraviglie”, alice nel paese delle meraviglie e attra- verso lo specchio, roma, newton compton, , pp. - . carter, a., the bloody chamber, london, vintage, . la camera di sangue, milano, feltrinelli, . Ėjzenštejn, s.m. - pomati, s. (a cura di), walt disney, milano, se, . franci, g. - zago, e., la bella addormentata. genere e metamorfosi di una fiaba, bari, dedalo, . gancitano, m., malefica. trasformare la rabbia femminile, roma, tlön, . grimm, j. & w., “rosaspina”, noel, d. (a cura di), le fiabe dei fratelli grimm, logos, modena, , pp. - . justice, b., “maleficent reborn: disney’s fairytale view of gender reaches puber- ty”, social education, / ( ), pp. - . perrault, c., “la bella addormentata nel bosco”, perrault, c. - vidale m. (a cura di), tutte le fiabe, roma, donzelli, , pp. - . perrault, c., “la bella addormentata nel bosco”, perrault c., i racconti delle fate, http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - lo schermo tra le pagine. per una rilettura della bella addormentata nel bosco. genesi e metamorfosi di una fiaba. d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . trad. it. collodi c., rizzoli, milano . soriano, m., i racconti di perrault. letteratura e tradizione orale, palermo, sellerio, . tenèze, m.l. - delarue, p., le conte populaire français. catalogue raisonné des versions de france et des pays de langue française d-outre-mer, nouvelle édition en un seul volume, paris, maisonneuve & larose, . thiolier méjean, s., une belle au bois dormant médiévale. frayre de joyet sor de plaser. nouvelle d’oc du xive siècle, paris, presses paris sorbonne, . vallino, m. - montaruli, v., artemisia e le altre. miti e riti di rinascita nella violenza di genere, roma, armando, . von franz, m.l., il femminile nella fiaba, torino, bollati boringhieri, . zipes, j., la fiaba irresistibile, roma, donzelli, . sitografia albanese, m., “venezia – il primo giorno”, stanze di cinema, sett. . internet - . . . faggi, m., “venezia – orizzonti – la belle endormie di catherine breillat”, indie eye.it, sett. . internet - . . . mascagni, f., “life in not a fary tale, la belle endormie, a new movie of catherine breillat”, elitism magazine, ago. . internet - . . . faggi, m., “la belle endormie di catherine breillat”, indie- eye network, settem- bre . internet - . . . grosoli, m., “la belle endormie di catherine breillat”, kinematrix.net, sett. . internet - . . . seastrom, l. o., “marc davis: style & compromise on sleeping beauty”, walt dis- ney family museum, agosto . internet - . . . vignati, r., “la belle endormie di catherine breillat”, nonsolocinema.com, sett. . internet - . . . tarasco, p., “attraverso i tabù”, loudvision.it, sett. . internet - . . < http://www.loudvision.it/attraverso-i-tabu>. zimmer, b., “why maleficent is a magnificent villain name”, visual thesaurus, giu. . internet - . .. http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . revista internacional de culturas y literaturas, junio issn: - angela articoni d o i: htt p: // d x. d oi .o rg / . / r ic l . . i . filmografia barbe bleue, regia catherine breillat, soggetto charles perrault, sceneggiatura ca- therine breillat, francia, . biancaneve (snow white and the seven dwarfs), regia david hand, soggetto f.lli grimm, sceneggiatura dorothy ann blank et al., usa, . la belle endormie, regia catherine breillat, soggetto charles perrault, h.c. ander- sen, sceneggiatura catherine breillat, francia, . la sirenetta (the little mermaid), regia ron clements, john musker, soggetto hans christian andersen, sceneggiatura ron clements, john musker, usa, . maleficent, regia robert stromberg, soggetto charles perrault, fratelli grimm et al., sceneggiatura linda woolverton, usa, . la bella addormentata nel bosco (sleeping beauty), regia clyde geronimi et al., sog- getto charles perrault, sceneggiatura joe rinaldi et al., usa, . http://dx.doi.org/ . /ricl. .i . http://dx.doi.org/ . /ricl. .i . arxiv:hep-ex/ v jan ar x iv :h ep -e x/ v ja n beauty – conference summary and future prospects tim gershona adepartment of physics, university of warwick, coventry, cv al, uk the status of b physics, cp violation and related measurements at the time of the beauty conference are summarized. particular attention is given to the exciting prospects that lie ahead, at the commencement of the lhc era, and beyond. . introduction beauty , the th international confer- ence on b physics at hadron machines, took place at a particularly pertinent time for the subject of the conference. while progress in b physics has, in recent years, been dominated by the spectacular successes of the e+e− b factories (principally babar and belle, but also cleo), can make a strong claim to be the first year for a long time in which the most inter- esting results have originated from hadron ma- chines. with the lhc start up becoming tan- talizingly close, does this mark the beginning of a new era for flavour physics? will results from cdf and dØ, and then atlas, cms and (par- ticularly) lhcb take the headlines in the coming years, or can the b factories continue to find in- novative methods to maximize the physics return from their unprecedented samples of data? look- ing further ahead, will an upgraded lhcb be able to harness the enormous quantities of b hadrons produced [ ], and fully exploit the potential for flavour physics at a hadron machine? will e+e− machines reach to even higher luminosities [ ], with a “super flavour factory” to complete the picture? such questions provided the subtext to the con- ference, which was illuminated by numerous ex- cellent presentations and lively discussions, con- ducted in a notably convivial atmosphere. since it appears impossible to do justice to all the con- tent, this summary will be selective, and focus on physics with b mesons (regrettably excluding im- portant topics in charm [ , ] and charmonia [ ], amongst others, that are summarized elsewhere). . the unitary triangle the agreement (or otherwise) of flavour physics results with the cabibbo-kobayashi-maskawa [ ] mechanism for quark mixing is usually illustrated in terms of measurements of the properties of the so-called “unitary triangle” (ut). the colourful images provided by the ckmfitter [ , ] and ut- fit [ ] groups clearly show the consistency (or lack thereof) of the existing constraints with the stan- dard model (sm), to the extent that these images are nowadays almost ubiquitous (and therefore unnecessary to reproduce here). below, the sta- tus of measurements of the properties of the ut is summarized [ ]. β the “golden mode,” b → j/ψ k , and its relatives, provide a theoretically clean measure of sin( β) [ ]. as the main raison d’être of the b factories, the measurements are updated regu- larly; the most recent updates [ , ] take advan- tage of the majority of a combined data sample that now exceeds ab− (about bb̄ pairs). [as prof. peach imparted after the conference banquet, the luminosity frontier is now charting the “attoworld”, just as the energy frontier will soon explore the “terascale”.] the world average is sin( β) = . ± . . three different approaches to resolve the am- biguity in the solutions for β from the above con- straint have been attempted. they use: ) b → j/ψ k∗ [ , ]; ) b → d(∗)h with d → http://export.arxiv.org/abs/hep-ex/ v k s π+π− [ , ]; and, new this year, ) b → d∗+d∗−k s [ ]. the results from all three prefer the sm solution (β = ( . ± . )◦). yet while it is straightforward to draw a qualitative conclusion, quantifying the degree to which the alternative solution is disfavoured is extremely difficult, since each of the above methods suffers from highly non-gaussian errors, either statistical in nature or related to hard-to-quantify hadronic param- eters. updated measurements (particularly for j/ψ k∗) and theoretical reassessments (particu- larly for d∗d∗k s ) will help. α measurements of α using mixing-induced cp violation in b → uūd transitions are complicated by the possible presence of sizeable penguin con- tributions [ ]. nonetheless, impressive progress has been made [ ]. in the most recent updates in the b → ππ system, babar [ ] have con- firmed the large cp violation previously observed by belle, who in turn have now observed [ ] a large direct cp violation effect. the results are summarized in fig. . while there is still some discrepancy between the obtained values of the direct cp violation parameter, it now seems clear that large ( % or greater) direct cp violation is present in b → π+π−. future measurements should resolve the precise value. the extraction of α from these measurements is performed using an isospin analysis, which re- quires measurements of the rates and asymme- tries of the remaining b → ππ decays. somewhat surprisingly, there are differences in the details of the outcome between versions of the analysis per- formed using frequentist [ ] or bayesian [ ] sta- tistical treatments. nonetheless, if one bears in mind that solutions close to α = are disfavoured for various reasons, both analyses agree that the sm solution (α close to ◦) is consistent with the data. the same is also true for results from the b → ρπ system (in which both experiments now have results from time-dependent dalitz plot analyses of b → π+π−π [ , ]), and from the b → ρρ system [ , ], where the first evidence for the decay b → ρ ρ has recently been found by babar [ ]. it will be interesting to see how well lhcb can contribute to these challenging π+ π- scp vs ccp contours give - ∆(ln l) = ∆χ = , corresponding to . % cl for dof - . - . - . - . - . - . - . - . scp ccp babar belle average h f a gh f a g ichep preliminary figure . summary of time-dependent cp viola- tion in b → π+π−. scp and ccp are param- eters of mixing-induced and direct cp violation, respectively. the contours indicate ∆χ = . for more details, see [ ]. measurements [ ]. γ the cleanest measurement of γ can be made in the b → d(∗)k(∗) system [ ], and the most constraining results to date use d → k s π+π− decays [ ]. the most recent results from babar [ ] and belle [ ] are summarized in fig. . despite impressive improvements in the analyses (notably in the χ /ndf obtained by babar [ ] in the fit to flavour-tagged d decays, used to obtain the d decay model), a large un- certainty remains due to the chosen model and hence assumed phase variation across the dalitz plane. it will be very hard to significantly re- duce this error without the concurrent analysis of large samples of cp-tagged d mesons, such as those produced by cleo-c [ , ]. to optimize the precision on γ, it is necessary to combine results using as many d decays as dk+, d→ksπ +π- contours give - ∆(ln l) = ∆χ = , corresponding to . % cl for dof - . - . . . - . - . . . x y babar b+ belle b+ babar b- belle b- averages h f a gh f a g ichep preliminary figure . summary of results in b± → dk±, with d → k s π+π−. cp violation (due to γ = ) would result in a difference between b+ and b−. the contours indicate ∆χ = , but do not in- clude d decay model uncertainty. for more de- tails, see [ ]. possible (within the b → dk system) [ ]. this year, the first analysis using d → k±π∓π has been performed by babar [ ], which can now be added to the list of modes available to make the constraints. additionally, many new chan- nels may become accessible in the coming years, including several which are particularly interest- ing for analysis at lhcb [ ]. notably, none of the channels used to date have yet shown any sig- nificant effect of the suppressed amplitude, sug- gesting that the ratio of amplitudes rb may be smaller than näıvely expected. vub and vcb the sides of the ut are obtained through measurements of rates, appropriately normalized. measurements of both vub and vcb have reached an impressive precision, the latter running into theoretical uncertainties at the – % level in in- clusive channels (with larger theory errors for ex- clusive modes) [ ]. analysis of moments of the inclusive decay spectra allow continuing refine- ments [ ]. the improved understanding also aids the extraction of vub, where the errors from exclusive and inclusive approaches are compara- ble (though the results are not in perfect agree- ment) at about % [ , ]. the inclusive analy- sis is dominated by new results from babar [ ], belle [ ] and cleo [ ] in the b → πlν chan- nel, complemented by improved lattice calcula- tions [ ]. vtd and vts the final side of the ut can be obtained from measurements of ∆md, the frequency of b –b̄ oscillations, but, to keep the theoretical uncer- tainty under control, more precise constraints can be obtained if the mixing rate is normal- ized to that in the b s system, ∆ms. the ratio, ∆md/∆ms gives |vtd/vts| up to su( ) breaking terms that can be calculated in lattice qcd. in contrast to many measurements which are experimentally challenging since they rely on small effects, ∆ms is hard to measure since it is large, and hence resolving the b s oscillations is difficult. while lower bounds on ∆ms have existed for several years, saw the first up- per bound [ , ], followed by the first mea- surement [ ] of the quantity. the sensation of beauty was the presentation of the improve- ment of this latter analysis [ , ], to include more decay modes and improved reconstruction and flavour tagging. the significance of the os- cillation signal, shown in fig. , now exceeds σ, with the value ∆ms = . ± . (stat) ± . (syst) ps− . one of the many impressive features of the new analysis is the sensitivity (in- dicating the largest value of ∆ms which could be measured) of . ps− – almost twice as large as the true value. another is that of the three con- tributions to the uncertainty on |vtd/vts|, that from the measurement of ∆ms is smaller than that from the measurement of ∆md, which in turn is smaller than that from lattice calculations of the hadronic parameters involved [ ]. less than a year ago, no measurement existed; as of beauty , ∆ms is known to subpercent pre- cision. this remarkable achievement opens the door to numerous b s decay channels, for which mixing-induced cp violation can best be studied at hadron machines. ]− [pssm∆ lo g (l ) ∆ − combined hadronic semileptonic cdf run ii preliminary − l = . fb figure . log likelihood curves for ∆ms. . new physics searches the above measurements, and others, combine to give constraints on the elements of the ckm matrix. since these include four free and funda- mental parameters of the sm, improving the pre- cision of these measurements is an important goal in its own right. yet the oft-discussed shortcom- ings of the sm remain, and the paramount objec- tive in high energy physics today is to search for the “new physics” (np) by which at least some of these problems may be resolved. b physics pro- vides a number of routes to search for np, not least through the consistency of ut constraints. indeed, there is currently “tension” between the measurements of vub and sin( β) discussed above, though improvements in both experimental and (in the case of vub) theoretical uncertainties will be necessary to discover if this is indeed a hint of a np signal. sin( βeff ) another interesting approach to search for np effects is to compare the sm reference measure- ment of sin( β) with the values for the same pa- rameter obtained in decays dominated by b → s penguin amplitudes [ ]. such flavour changing neutral current transitions are susceptible to the effects of np particles, which may appear as vir- tual particles in loops, even if they are too massive to be observed at the energy frontier. a compi- lation of relevant results is shown in fig. . an important improvement was made in with the first time-dependent dalitz plot analysis of b → k+k−k , including intermediate states such as φk [ ]. the results also include the most recent updates in the channel b → η′k from babar [ ] and belle [ ], wherein both ex- periments have now observed (with more than σ significance) mixing-induced cp violation. it has been frequently commented upon that all the measurements in fig. take central val- ues below the sm reference point (meanwhile, calculations of corrections due to subleading sm amplitudes tend to prefer larger values). since each channel has different sm uncertainties, and since there may be systematic correlations be- tween the measurements, taking a simple aver- age is ill-advised (if one does so anyway, the sig- nificance of the effect is about . σ). moreover, there is no significant discrepancy in any particu- lar channel. to interpret the data therefore re- quires care. perhaps wisdom can be found in the words of sir francis bacon, whose connection with oxford was presented by prof. cashmore in the opening address to the conference: “the root of all superstition is that men observe when a thing hits, but not when it misses.” the less philosophically inclined may simply find it prudent to wait for more data. charmless hadronic b decays decays of the type b → hh′ can be similarly sensitive to np effects. these modes have also proved fertile ground for testing theoretical con- cepts [ ]. for several years the data have pre- sented a “kπ puzzle,” in that the pattern of sin( βeff) ≡ sin( φe ff) h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s h f a g d p f /j p s b→ccs φ k η′ k k s k s k s π k s ρ k s ω k s f k π π k s k + k - k - - - world average . ± . babar . ± . ± . belle . ± . ± . average . ± . babar . ± . ± . belle . ± . ± . average . ± . babar . ± . ± . belle . ± . ± . average . ± . babar . ± . ± . belle . ± . ± . average . ± . babar . ± . ± . average . ± . babar . +- . . ± . belle . ± . ± . average . ± . babar . ± . belle . ± . ± . average . ± . babar - . ± . ± . average - . ± . babar q b . ± . ± . ± . belle . ± . ± . +- . . average . ± . h f a gh f a g dpf/jps preliminary figure . compilation of measurements of mixing-induced cp violation in decays domi- nated by the b → s penguin amplitude, compared to the world average from b → cc̄s transitions. from [ ]. rates and asymmetries in such decays was not in good agreement with the sm prediction. while this effect is largely reduced after the most re- cent updates [ , ], which use improved treat- ments of radiative corrections, several discrepan- cies remain: the b → π π branching fraction is larger than most predictions, and most models have difficulty explaining the observed difference in cp asymmetries for the channels b → k+π− and b+ → k+π . recently, results from the tevatron have extended the experimental reach to include b s and b baryon decays – first obser- vations of three such decay channels were pre- sented at beauty [ , ], as shown in fig. . these results, and their future improvements [ ], may throw new light on the “kπ puzzle.” how- ever, to complete the set of measurements will re- quire studies of decays such as b s → k s k s and b s → k s π that are not easily, if at all, accessi- ble at a hadron machine, but may be measured at an e+e− machine operating at the Υ( s) [ , ]. ] -mass[gev/cππinvariant . . . . . . . . c a n d id a te s p e r m e v /c ] -mass[gev/cππinvariant . . . . . . . . c a n d id a te s p e r m e v /c - = fb int cdf run ii preliminary l -π+ k→ b +π - k→ b - k + k→ s b/s b -π+π → b/ b -π+ k→ s b ++π - k→ s b +πp → b Λ+ -π p→ b Λ + kp → b Λ+ - pk→ b Λ combinatorial backg. three-body b decays figure . signals for b decays to hh′ final states. electroweak penguin decays since decays to hadronic final states are limited by theoretical uncertainties, electroweak penguin decays (b → sγ and b → sll) provide cleaner tests of the sm. the measurement of the rate of the b → sγ decay has provided a strict constraint that must be satisfied by new physics model builders; recent improvements in the sm calculation to nnll allow this approach to be pushed even fur- ther [ ]. meanwhile, measurements of asymme- tries (such as cp , isospin and forward-backward asymmetries) provide additional tests of the sm, and some enticing hints for np effects, that – as usual – require confirmation with larger data samples [ – ]. since much larger statistics are necessary to probe the sm with precision, it is gratifying that many of these channels (such as b → k∗ µ+µ− and b s → φµ+µ−) can be stud- ied at hadron machines [ , ]. leptonic decays the archetypal channel for np effects in flavour physics to be observed at a hadron collider is b s → µ+µ−. this rare decay can be enhanced even in the minimal flavour violation (mfv) scenario – a principle that can be neatly encap- sulated in the words of sir francis bacon thus: “god hangs the greatest weights upon the smallest wires.” [rare kaon decays also play a pivotal rôle within mfv, but are not within the remit of this sum- mary.] the latest upper limits on this channel are still more than an order of magnitude away from the sm expectation [ – ], though it is expected that this mode can be observed by all of atlas, cms and lhcb within a few years of lhc data taking [ ]. however, other leptonic decays, such as those involving τ leptons and/or neutrinos (no- tably the recently discovered b+ → τ+ντ [ ]), that are also sensitive to np, can only be studied at a b factory [ ]. φs and other mixing parameters though the value of ∆ms (normalized to ∆md) has now been found to be consistent with the sm expectation, it remains possible that there may be large np effects in b s mixing [ ]. these may be uncovered through measurements of pa- rameters such as ∆Γs, as well as through cp violation in mixing (i.e. the semileptonic decay asymmetry [ , ]) and in the mixing phase φs. the first untagged analysis of φs has been carried out [ , ] – note that this approach relies heavily on the size of ∆Γs, and could be pursued at the Υ( s) [ ]. however, now that ∆ms is measured, the complete tagged, time-dependent analysis is possible, which will improve the sensitivity dra- matically [ ]. . what remains for b physics? the above discussion should emphasise the rich phenomenology for np effects in the b system. yet all results to date are consistent with the standard model, and it is legitimate to ask if whether studies of such particles are the best way to improve knowledge about fundamental physics. another way to approach this question, is to ask whether measurements in b physics may provide the kind of surprising result that can have a similar impact to the initial observation of cp violation in the decay k l → π+π− [ ]? aside from the historical record of flavour physics in uncovering new particles, the answer is clear: indeed such groundbreaking results are possible. any of the following, if observed, would provide incontrovertible proof of physics beyond the sm: inconsistent cp violation phenomena (in, e.g. hadronic b → s penguin decays); new flavour-changing neutral currents; unpolar- ized photons emitted in radiative b decays; large cp violation effects in b s mixing; enhanced rare decays (e.g. b s → µ+µ−). cp violation in charm and lepton flavour violation in τ decays are similarly potent observables. although clear sig- nals for np have not yet been observed, the preci- sion of the measurements does not exclude contri- butions of o( %) or, in many cases, much larger. some np models allow such effects, though they may be unlikely in some others (which assume connections with other existing constraints). yet it must be remembered that new physics is new, and its effects are unknown. since searches for np effects in flavour physics are completely com- plementary to those that can be achieved at the high energy frontier, it is essential to continue to pursue this activity vigorously. the preparations for the lhc are well ad- vanced, and entering an exhilarating stage as the first data come closer to reach. each of atlas [ – ], cms [ , ] and lhcb [ – ] is well positioned to exploit the b physics potential of the early running. much has been learned from the recent operational experience of cdf [ ] and dØ [ , ], culminating in the results presented in this conference. more than any other factor, this provides great hope that the passage from first data to published results may not be too ar- duous. notably, the cdf trigger system [ ] has led to successful analyses of hadronic b decays, in- cluding the observation of new particles decaying into fully hadronic final states [ , ]. however, any optimism should be tempered with caution, since the clearest message of all is that a great deal of hard work lies in between the data and the results! . summary it may be useful to reflect on the various ob- servations of cp violation to date. limiting the discussion to channels where effects of more than σ significance have been seen, these include cp violation in • k − k̄ mixing (ǫk ); • interference between s → uūd and s → dd̄d amplitudes (ǫ′); • interference between b − b̄ mixing and – b → cc̄s amplitudes (j/ψ k ); – b → uūd amplitudes (π+π−); – b → ss̄s amplitudes (η′k ); • interference between b → uūd and b → dd̄d amplitudes (π+π−); • interference between b → sūu and b → uūs amplitudes (k+π−). the consistency of all these observed effects with the ckm mechanism demonstrates the tremendous success of the sm. however, cp vio- lation has not yet been observed in the decays of any charged meson, nor of any charmed particle, nor of any baryon, nor of any lepton. clearly, a great deal remains to be explored, and np effects may be just around the corner. the final summary of beauty can be given in the words of sir francis bacon: “the best part of beauty is that which no picture can express.” . acknowledgements i wish to extend my warmest gratitude to the organizers for offering me the tremendous oppor- tunity to summarize such an exciting conference. a conference in oxford also provides the perfect opportunity to acknowledge the enormous contri- butions to the field of the late prof. dalitz [ ]. references . f. muheim, these proceedings. . a. bevan, these proceedings. . d. asner, these proceedings. . see also the contributions of h. band, these proceedings; r. muresan, ibid.; b. reisert, ibid.; p. zweber, ibid. . b. yabsley, these proceeedings. . n. cabibbo, phys. rev. lett. 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( ) . . h. burckhart, these proceedings. . p. eerola, these proceedings. . j. kirk, these proceedings. . o. buchmuller, these proceedings. . f.-p. schilling, these proceedings. . l. garrido, these proceedings. . g. corti, these proceedings. . e. rodrigues, these proceedings. . h. ruiz, these proceedings. . a. annovi, these proceedings. . d. bauer, these proceedings. . t. moulik, these proceedings. . j. pursley, these proceedings. . r. mommsen, these proceedings. s. behari, ibid. . i.j.r. aitchison, f.e. close, a. gal and d.j. millener, nucl. phys. a ( ) . searching for beauty-fully bound tetraquarks using lattice nonrelativistic qcd searching for beauty-fully bound tetraquarks using lattice nonrelativistic qcd ciaran hughes, ,* estia eichten, ,† and christine t. h. davies ,‡ fermi national accelerator laboratory, batavia, illinois , usa supa, school of physics and astronomy, university of glasgow, glasgow g qq, united kingdom (received october ; published march ) motivated by multiple phenomenological considerations, we perform the first search for the existence of a b̄b̄bb tetraquark bound state with a mass below the lowest noninteracting bottomonium-pair threshold using the first-principles lattice nonrelativistic qcd methodology. we use a full s-wave color/spin basis for the b̄b̄bb operators in the three þþ, þ− and þþ channels. we employ four gluon field ensembles at multiple lattice spacing values ranging from a ¼ . – . fm, all of which include u, d, s and c quarks in the sea, and one ensemble which has physical light-quark masses. additionally, we perform novel exploratory work with the objective of highlighting any signal of a near threshold tetraquark, if it existed, by adding an auxiliary potential into the qcd interactions. with our results we find no evidence of a qcd bound tetraquark below the lowest noninteracting thresholds in the channels studied. doi: . /physrevd. . i. introduction tetraquarks were first considered theoretically decades ago in the context of light-quark physics in order to explain, amongst other experimental features, the a ð Þ and f ð Þ broad resonances [ ]. more recently, there has been exciting experimental evidence indicating the poten- tial existence of tetraquark candidates amongst the so- called xyz states—states whose behavior differs from predictions of the heavy quark-antiquark potential model. the observed xyz states apparently contain two heavy quarks, ðcc̄Þ or ðbb̄), and two light quarks [ ]. the dynamics of these systems involves both the short-distance and long-distance behavior of qcd and hence theoretical predictions are difficult. consequently, many competing phenomenological models currently exist for these states [ ]. lattice qcd studies of the observed xyz states are also difficult because these states are high up in the spectrum as well as being in the threshold region for strong decays into two heavy flavor mesons. while there are theoretical arguments that some tetraquark states with doubly heavy flavor (e.g., bbūd̄, bbūs̄ and bbd̄s̄) should be bound and stable against all strong decays [ ], no general arguments exist for tetraquarks with heavy quark-antiquark content such as qq̄ qq̄ states. a tetraquark system composed of four heavy quarks is a much cleaner system to study theoretically as long-distance effects from light quarks are expected not to be appreciable, as opposed to systems which are a mixture of heavy and light quarks. in the limit of very heavy quarks perturbative qcd single-gluon exchange dominates [ ] and so the dynamics are relatively simple. this makes these systems particularly useful to study in order to shed light on the aforementioned xyz states. in fact, there is a multitude of phenomenological models (with a quark mass ranging from the bottom to the very heavy limit) which predict the existence of a q̄q̄qq bound tetraquark [ – ]. however, these are not calculations from first principles and have an unquantifiable systematic error associated with the choice of four-body potential. in reality, the heaviest possible tetraquark system in nature would be a b̄b̄bb tetraquark. for this, nonperturbative qcd cannot be ignored, making a first-principles lattice qcd study essential. if such a bound b̄b̄bb tetraquark did exist, how it would be observed at the lhc has already been addressed [ , ]. given these pressing theoretical motivations, in this work we perform the first lattice qcd study of the b̄b̄bb system. the sole objective of this exploratory work is to determine if the dynamics of qcd generates enough binding force between the b̄b̄bb to produce a tetraquark state with a mass below the lowest noninteracting botto- monium-pair threshold, ensuring that it is stable against simple strong decays. searching for such a bound b̄b̄bb *chughes@fnal.gov †eichten@fnal.gov ‡christine.davies@glasgow.ac.uk published by the american physical society under the terms of the creative commons attribution . international license. further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and doi. funded by scoap . recent lattice studies of the scattering amplitude pole do indicate that these states are in fact resonances as opposed to cusp effects etc. [ , ]. physical review d , ( ) - = = ( )= ( ) - published by the american physical society https://crossmark.crossref.org/dialog/?doi= . /physrevd. . &domain=pdf&date_stamp= - - https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://creativecommons.org/licenses/by/ . / https://creativecommons.org/licenses/by/ . / tetraquark candidate is particularly well suited to the first- principles lattice qcd methodology because this state, if it existed, would be the ground state in the b̄b̄bb system. this means that it should be relatively easy to identify. further, b̄b̄bb annihilation effects are strongly suppressed by the heavy-quark mass, as in the bottomonium system, and so can be ignored. this paper is organized as follows: in sec. ii the inter- polating operators used in this study are discussed, in sec. iii the computational methodology is given, while the majority of the results are presented in sec. iv. in sec. v we explore a novel method of adding an auxiliary potential into qcd with the objective of highlighting a possible tetraquark signal. we then discuss our conclusions in sec. vi. ii. infinite-volume continuum eigenstates, operators and two-point correlators the qcd fock space contains all color-singlet single- particle states such as the conventional mesons jηbðkÞi, jΥðkÞi etc. and, if a b̄b̄bb bound state also exists, a tetraquark state jt bðkÞi. in addition, there are also the two-particle states which can be labeled by appropriate quantum numbers as jptot; jpc; jkrelj; jp c ; jp c ; lreli where ptot (j pc) is the total (angular) momentum of the two-particle system, with jpicii being the quantum numbers of the individual particles and krel (lrel) the relative (orbital angular) momentum between the two particles. the sole motivation of this work is to search for a possible b̄b̄bb tetraquark candidate within qcd that couples to a bottomonium pair and which lies below the lowest threshold. the bottomonium mesons we study can be classified as jpc ¼ sþ lj. as any orbital angular momenta are expected to raise the internal kinetic energy of the state (and hence its rest mass) we focus on two-body s-wave systems (l ¼ ) with no orbital angular momen- tum between them (lrel ¼ ). with the quantum numbers of the Υ=ηb being jpc ¼ −−= −þ, the s-wave ηb and Υ can have (through the addition of angular momenta) a quantum number of þþ, while the Υηb has þ− and the Υ can also be in a þþ configuration. we now want to construct a full basis of s- wave color/spin interpolating operators that has overlap with these quantum numbers. to do so, we start by forming all possible color combinations that the b̄ and b can be in. these are specified in table i. we can construct meson interpolating operators as o ð Þ m ðt; xÞ ¼ g ð Þ efg b̄fΓmbgðt; xÞ; ð Þ where Γm ¼ iγ ; γk projects onto the quantum numbers of the ηb and Υ respectively, and g ð Þ efg is the color projection onto the singlet (octet). in addition, it is also possible to construct a (anti-) diquark operator as o ̄ð Þ d ðt; xÞ ¼ g ̄ð Þ efg b̄ ĉ f Γdbgðt; xÞ; ð Þ o ð ̄Þ a ðt; xÞ ¼ g ð ̄Þ efg b̄fΓab ĉ g ðt; xÞ; ð Þ where ðbĉÞα ¼ cαβb̄β is the charge-conjugated field with c ¼ −iγ γ . as the two quarks have the same flavor, the pauli-exclusion principle applies and the wave function has to be completely antisymmetric. with our choice to focus on s-wave combinations of particles, the spatial wave function must be symmetric. as the color (triplet) sextet has a (anti) symmetric color wave function, this forces the spin-wave function to be in a (triplet) singlet with (Γ ¼ γk) Γ ¼ iγ . with these building blocks, we can form four classes of b̄b̄bb color singlets by contracting the color factors g in any irreducible representation (irrep) with its conjugate color factors, i.e., c × c, c × c, c × ̄c and c × ̄c. these suð Þ invariant color contractions are given in table i. after doing this, we need to project the operators onto a specific angular momentum jp by using the standard soð Þ clebsch-gordan coefficients (using a spherical basis of spin matrices [ ]) as oj;mðp;qÞðt; xÞ ¼ x m ;m hj; mjj ; m ; j ; m i × oj ;m p ðt; x þ rÞoj ;m q ðt; xÞ ð Þ with ðp; qÞ describing the blocks this configuration is built from, i.e., ðηb; ηbÞ, ðΥ; ΥÞ, ðd; aÞ, etc. we also allow the possibility of the two blocks being separated by a distance r. for the r ¼ case, the operators project onto a definite total angular momentum j. for the r ≠ case, one can taylor expand oj ;m p ðt; x þ rÞ around r ¼ to notice that the operator projects onto a superposition of quantum table i. the color representations of the different quark combinations. note that, as described in the text, once the color representation of the (anti-) diquark is chosen, the pauli-exclusion principle enforces certain spin combinations in s-wave. also given are the suð Þ color contractions needed for the b̄b̄bb operators. b b̄ b̄b b̄b̄ bb color irrep c ̄c c, c c, ̄c ̄c; c g efgg ef g δfgδf g g efgg ef g δfg δf g − δfgδf g = g efgg ef g ðδff δgg − δfg δgf Þ= g efgg ef g ðδff δgg þ δfg δgf Þ= γ ¼ diagð ; − Þ in the convention used by nrqcd. since the c irrep of suð Þ is the adjoint, it is similar to its conjugate ̄c. hughes, eichten, and davies phys. rev. d , ( ) - numbers. consequently, it is possible to utilize this to further search for the lowest ground state of the four quark system. when dealing with the diquark components, to project onto a definite value of charge conjugation in eq. ( ) one can form the linear combination o ;m d o ;m a � o ;m d o ;m a . in fact, not all of these color combinations are indepen- dent. fierz relations constrain the number of independent color-spin operators that are possible. for the local oper- ators in s-wave, the relations between the two-meson and diquark-antidiquark states are given in table ii. the simplest quantity that can be calculated on the lattice in order to extract particle masses is the euclidean two- point correlator. this is defined as cj pc i;j ðt; ptot ¼ Þ ¼ z d xhoj;mii ðt; xÞo j;mj j ð ; Þ†i ð Þ where we choose to project to zero spatial momentum and i, j label potentially different operators at the source and sink with the same jpc, e.g., i ¼ ðηb; ηbÞ, j ¼ ðΥ; ΥÞ. the single-particle contributions to the correlator are deter- mined by inserting a complete set of single-particle states in the hilbert-space formalism into eq. ( ) to yield cj pc i;j ðt; ptot ¼ Þ ¼ x n zinz j;� n e−ent ð Þ with zin ¼ h joj;mii jni being the nonperturbative overlap of the operator to the eigenstate jni and enjni ¼ hjni the energy eigenvalue. note that all states jni with the same quantum numbers contribute to this correlator, e.g., for the bottomonium −þ pseudoscalar correlator the jηbi as well as all radial excitations contribute. the two-particle contributions to the correlator are slightly more complicated. in this case, as derived in appendix a, the nonrelativistic two-particle states give a contribution to the correlator that is cj pc i;j ðt;ptot ¼ Þ ¼ � μr πt � x x e−ðm s þms Þt × � z x þz x ðtμrÞ þz x ðtμrÞ þ�� ð Þ where the sum is over all distinct two-particle states x with quantum numbers jpc and ptot ¼ , msi (mki ) is the static (kinetic) mass of the particles, as defined in eq. ( ), μr ¼ mk m k =ðmk þ mk Þ is the reduced mass and z lx are nonperturbative coefficients. energies of states can be extracted using the above functional form once the correlator has been computed. examining eq. ( ) in the path-integral formalism we can perform the connected wick contractions so that the correlator can be written as an integral over the gluon fields with the integrand consisting of products of b-quark propagators. for each two-meson-type operator, e.g., o cηbo c ηb, as all quarks have the same flavor there are four connected wick contractions. these are shown diagram- matically in fig. . the first wick contraction for the two-meson correlator, called direct and shown in fig. (a), has the expression gradeg r ad e g r bghg r bg h x x tr½Γm k− ðt; x; ; zÞe g × Γ†m k − ðt; x; ; zÞ†hd �tr½Γm k− ðt; x ; ; z Þeg × Γ†m k − ðt; x ; ; z Þ†h d� ð Þ table ii. fierz relations in the b̄b̄bb system relating the two- meson and the diquark-antidiquark bilinears. jpc diquark antidiquark two meson þþ ̄c × c − j ; ΥΥi þ ffiffi p j ; ηbηbi þþ c × ̄c ffiffi p j ; ΥΥi þ j ; ηbηbi þ− ̄c × c ffiffi p ðj ; Υηbi þ j ; ηbΥiÞ þþ ̄c × c j ; ΥΥi (a) direct (b) xchange (c) direct (d) xchange fig. . there are four connected wick contractions for the two- meson-type correlator when the quarks have the same flavor. the grey region represents a color neutral meson, the blue line a quark and the red line an antiquark. we call these the (a) direct contraction where each meson propagates to itself, (b) xchange where an antiquark is exchanged between the meson pair, (c) direct where each meson propagates to the other, and (d) xchange where a quark is exchanged between the meson pair. annihilation diagrams are suppressed by powers of the heavy-quark mass [ ] and are expected to be negligible. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - while the second, called xchange , is given by − gradeg r ad e g r bghg r bg h x x tr½Γm k− ðt; x; ; zÞe g × Γ†m k − ðt; x ; ; zÞ†hdΓm k− ðt; x ; ; z Þeg × Γ†m k − ðt; x; ; z Þ†h d � ð Þ where x ¼ x þ r. the other diagrams, direct and xchange , have similar expressions. for the diquark- antidiquark-type operators, e.g., o cd o ̄c a , there are also four wick contractions which can be combined into one expression as cj pcðt; ptot ¼ Þ ¼ ½ � sgnðcΓdÞt � sgnðcΓaÞt þ sgnðcΓdÞtsgnðcΓaÞt�gradegrad e grbghgrbg h × x x tr½cΓdk− ðt; x; ; zÞeg Γ†dck− ðt; x; ; zÞtdh � × tr½Γack− ðt; x ; ; z Þ�e gcΓ†ak− ðt; x ; ; z Þ†hd � ð Þ where the sign function is defined by sgnðxÞt ¼ � if xt ¼ �x. the � in eq. ( ) corresponds to the or color representation. it is this prefactor with the signs which enforces the pauli-exclusion principle: the sum cancels for spin combinations that do not make the wave function overall antisymmetric. the spin-triplet/singlet configura- tions we consider here obey ðcγkÞt ¼ þðcγkÞ and ðcγ Þt ¼ −ðcγ Þ. diagrammatically the four connected wick contractions contributing to the diquark correlator are shown in fig. . to calculate the two-point correlators described above within the first-principles feynman path-integral approach to qcd needs the methodology of lattice qcd. we now discuss our lattice qcd approach. iii. lattice qcd methodology a. second generation nf = + + gluon ensembles our lattice calculation uses gauge field configurations generated by the milc collaboration [ ]. for the gauge fields, theyused the tadpole-improvedlüscher-weisz gauge action correct to oðαsa Þ [ ] and include þ þ flavors in the sea, the up and down quarks (treated as two degenerate light quarks with mass ml), the strange quark, and the charm quark. the sea quarks are included using the highly improved staggered quark formulation [ ]. four ensembles are chosen in this study. as one might expect roughly double the discretization errors in a b̄b system relative to the b̄b one, to ensure that the heavy-quark potential is accurately represented (where short-distance details may be important for a compact tetraquark candidate) we utilize three ensembles that span relatively fine lattice spacings ranging from a ¼ . – . fm. details of the ensembles are given in table iii. due to the computational expense, most of the ensembles use heavier ml than in the real world. however, to test ml dependence, we use one ensemble (set in table iii) that has physical aml=ams. additionally, the ensembles have been fixed to coulomb gauge to allow nongauge invariant nonlocal operators to be used [as constructed in eq. ( )]. b. b-quarks using inrqcd a nonrelativistic effective field theory is appropriate for physical systems where the relative velocity of the (a) (b) (c) (d) fig. . there are four connected wick contractions for the diquark-antidiquark-type correlator when the quarks have the same flavor. the blue shaded region represents a diquark, the red shaded region the antidiquark, a blue line a quark and the red line an antiquark. the uncrossing of the lines in fig. (b) to produce fig. (a) gives a �, as discussed in the text, which enforces the pauli-exclusion principle. table iii. details of the gauge ensembles used in this study. β is the gauge coupling. a (fm) is the lattice spacing [ , ], amq are the sea quark masses, ns × nt gives the spatial and temporal extent of the lattices in lattice units and ncfg is the number of configurations used for each ensemble. we use time sources on each configuration to increase statistics. ensembles and are referred to as “coarse,” as “fine,” and as “superfine”. set β a (fm) aml ams amc ns × nt ncfg . . ( ) . . . × . . ( ) . . . × . . ( ) . . . × . . ( ) . . . × hughes, eichten, and davies phys. rev. d , ( ) - constituent particles inside the bound state is much smaller than (in planck units). when applied to the strong force, this framework is called nonrelativistic qcd (nrqcd). it is well known that b-quarks are very nonrelativistic inside their low-lying bound states, where v ≈ . [ ]. for lattice nrqcd, the continuum nrqcd action is discretized onto the lattice [ ] with operators included to a predetermined level in v . here we use an action accurate through oðv Þ with additional spin-dependent terms at oðv Þ. operators are also added to correct for discretiza- tion effects. we make the further systematic improvement here, introduced in [ ], to include coefficients of oðv Þ operators that have been matched to continuum qcd through oðαsÞ. we call this improved nrqcd (inrqcd). this action has already been used to success- fully determine bottomonium s, p and d wave mass splittings [ , ], precise hyperfine splittings [ , ], b meson decay constants [ ], Υ and Υ leptonic widths [ ], b, d meson mass splittings [ ] and hindered m radiative decays between bottomonium states [ ]. the inrqcd hamiltonian evolution equations can be written as gðx; t þ Þ ¼ e−ahgðx; tÞ gðx; tsrcÞ ¼ δx;x ð Þ with e−ah ¼ � − aδhjtþ �� − ah jtþ n � n u†t ðxÞ × � − ah jt n � n � − aδhjt � ð Þ ah ¼ − Δð Þ amb ; aδh ¼ aδhv þ aδhv ; aδhv ¼ −c ðΔð ÞÞ ðambÞ þ c i ðambÞ ð∇ · ~e − ~e · ∇Þ − c ðambÞ σ · ð ~∇ × ~e − ~e × ~∇Þ − c amb σ · ~b þ c Δð Þ amb − c ðΔð ÞÞ nðambÞ aδhv ¼ −c ðambÞ fΔð Þ; σ · ~bg − c ðambÞ fΔð Þ; σ · ð ~∇ × ~e − ~e × ~∇Þg − c i ðambÞ σ · ~e × ~e: ð Þ the parameter n is used to prevent instabilities at large momentum from the kinetic energy operator. a value of n ¼ is chosen for all amb values. we evaluate the propagator using local sources eq. ( ). here, amb is the bare b quark mass, ∇ is the symmetric lattice derivative, with ~∇ being the improved version, and Δð Þ, Δð Þ are the lattice discretizations of Σid i , Σid i respectively. ~e, ~b are the improved chromoelectric and chromomagnetic fields, details of which can be found in [ ]. each of these fields, as well as the covariant derivatives, must be tadpole improved. we take the mean trace of the gluon field in landau gauge, u l ¼ h truμðxÞi, as the tadpole param- eter, calculated in [ , ]. the matching coefficients c , c , c , c , c in the above hamiltonian have been computed perturbatively to one loop [ , ]. c was found to be close to the tree-level value of one nonperturbatively [ ] and we set it, as well as the rest of the matching coefficients, to their tree-level values. the quark mass amb is tuned fully nonperturbatively in inrqcd [ ] using the spin-averaged kinetic mass of the Υ and ηb (which is less sensitive to spin- dependent terms in the action). the above hamiltonian neglects the four-fermion operators which appear at oðα sv Þ, as well as other operators which appear at higher order in the nonrelativistic expansion. simple power- counting estimates [ , ] would lead us to expect con- tributions of order a few percent (or a few mev) at most to binding energies from these terms. in the case where a tetraquark bound state is observed then we can estimate the systematic effect from neglecting these contributions. the parameters used in this study are summarized in table iv. there, c , c and c are the correct values for an oðv Þ inrqcd action [ ]. for set , all parameters are those for the oðv Þ action. the small changes to these coefficients in going to an oðv Þ inrqcd action (which are similar in magnitude to the two-loop corrections) are not appreciable for the purpose of this work: whether or not a tetraquark candidate exists below the lowest bottomo- nium-pair threshold. all other parameters listed in table iv are taken from [ , ]. within inrqcd the single-particle energy eigenstates can be decomposed in the standard nonrelativistic expan- sion as table iv. parameters used for the valence quarks. amb is the bare b-quark mass in lattice units, u l is the tadpole parameter and the ci are coefficients of terms in the nrqcd hamiltonian [see eq. ( ))]. details of their calculation can be found in [ , ]. c , c , c and c are included at tree level. set amb u l c , c c c c . . . . . . . . . . . . . . . . . . . . . . . . the spin-independent oðv Þ terms are subleading effects for the b̄ b̄ bb energies relevant to this study. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - eðpÞ ¼ ms þ jpj mk þ � � � ð Þ with ms, mk being the static and kinetic masses respec- tively [ ]. because the quark mass term is removed from the inrqcd hamiltonian, the static mass is unphysical, differing by a constant shift from the physical (kinetic) mass. this means that only static mass differences deter- mined fully nonperturbatively can be compared to exper- imental results. however, this constant shift can be calculated in lattice perturbation theory if required [ ], or by using an additional experimental input. the kinetic mass does not suffer this problem as it acquires the quark mass contributions from the quark kinetic terms [ ]. also, within inrqcd the dirac field Ψ can be written in terms of the quark ψ and antiquark χ as Ψ ¼ ðψ; χÞt. the propa- gator is then k− ðxjyÞ ¼ � gψðxjyÞ −gχðxjyÞ � ð Þ where gψðxjyÞ is the two-spinor component quark propa- gator and gχðxjyÞ is the two-spinor component antiquark propagator. taken together, we can now compute the b- quark propagator via the inrqcd evolution equations on the gluon ensembles listed in table iii. the last piece needed to calculate the two-point correlators, and hence energies, is the discretized finite-volume versions of the interpolating operators. c. discrete finite-volume operators together, the isotropic discretization and the periodic finite volume break the infinite-volume continuum soð Þ symmetry of nrqcd to the octahedral group, oh [ ]. thus, while the operators constructed in sec. ii have well- defined jpc quantum numbers associated with soð Þ, we need to construct operators which transform within the irreps of the oh symmetry group (relevant for lattice calculation). this can be achieved by the method of subduced representations, where an operator with a specific jpc can be taken to a specific lattice irrep Λpc by using the subduction coefficients found in appendix a of [ ]. at rest, each of our jpc ¼ þþ and jpc ¼ þ− operators trivially subduce into a single lattice irrep labeled by aþþ and tþ− respectively. however, the j pc ¼ þþ case is slightly more complicated and subduces into two lattice irreps labeled by tþþ and e þþ (which are three and two dimensional). we construct both the t =e operators asffiffiffi p o ½ � t =e ¼ oj¼ ;m¼ � oj¼ ;m¼− , which are correctly subduced from the j ¼ þþ operators defined in sec. ii. in principle, each lattice irrep allows mixing between different j states, e.g., the a irrep contains not only the j ¼ states but also the j ¼ [ ]. however in practice since we are only looking for the ground state of the b̄b̄bb correlators we are not sensitive to these mixing effects. a complete list of b̄b̄bb interpolating operators used to produce the correlator data herein is given in table v. in fact, this is an overconstrained set due to the fierz identities (shown in table ii) which relate the two-meson and diquark-antidiquark correlators. we include this overcon- strained system and ensure that we reproduce the fierz relations to numerical precision, performing a nontrivial check on our data. additionally, we also reproduce the relations between the c × c color combination and the others [ ] on a subset of the data. it has been found [ ] that separating each hadron within the two-hadron interpolating operator by a specific distance r can significantly aid in the extraction of the (ground) state energy. in this direction, we use three different spatial configurations of the b̄b̄bb correlators where the individual building blocks are separated by a distance of rx ¼ , or lattice units in the x-direction. finally, the subduced lattice interpolating operators are defined in terms of the dirac fields as in eq. ( ), and the correlators are defined analogously, as in eq. ( ). we can then use the decomposition of k− ðxjyÞ given in eq. ( ) with suitable boundary conditions to write the correlator in terms of the inrqcd quark propagator gψðxjyÞ. due to table v. the b̄b̄bb interpolating operators used in this study. operators in each column are subduced from the infinite-volume continuum quantum numbers jpc given in the first row. the superscript on each operator denotes the lattice irrep of that operator and the subscript denotes the building blocks of the operator, as explained in the text. we generate each operator with three different spatial configurations as shown in eq. ( ): where the building blocks are separated by a distance rx ¼ , or lattice units in the x-direction. þþ þ− þþ source sink source/sink source/sink oa ðηb;ηbÞ o a ðηb;ηbÞ o t ðΥ;ηbÞ o t ðΥ;ΥÞ oa ðηb;ηbÞ o a ðΥ;ΥÞ o t ðd ̄c ;a c Þ oeðΥ;ΥÞ oa ðΥ;ΥÞ o a ðηb;ηbÞ o t ðd ̄c ;a c Þ oa ðΥ;ΥÞ o a ðΥ;ΥÞ o e ðd ̄c ;a c Þ oa ðd ̄c ;a c Þ oa ðd ̄c ;a c Þ oa ðd c ;a ̄c Þ oa ðd c ;a ̄c Þ the conserved quantum numbers of a symmetry group are determined using the little group, which for soð Þ and oh depend on the momenta type [ ]. in this study we focus on states at rest. the ηb and Υ energies used to determine the noninteracting ηb and Υ thresholds (needed to determine if a state exists below them) are found from locally smeared meson correlators only. hughes, eichten, and davies phys. rev. d , ( ) - our use of inrqcd, there are no backward propagating valence antiquarks in our calculation. consequently, the appreciable finite-temporal effects seen in relativistic two- meson lattice correlators [ ] do not arise in our calcu- lation, simplifying the analysis. with this methodology, it is now possible to compute the lowest energy levels asso- ciated with the b̄b̄bb system. iv. the low-lying energy eigenstates of the + + , + − and + + b̄b̄bb system in order to determineif there is an energy eigenstate below the ηb threshold, we first need to find the noninteracting thresholds on each ensemble listed in table iii. this is achieved by computing the bottomonium ηb and Υ two- point correlators as described above, then fitting them to the functional form given in eq. ( ) to extract the single-particle energies. as in the range of studies listed in sec. iii b, amongst others, we utilize the well-established bayesian fitting methodology [ ] in this work and refer the reader to [ ] for technical details. although we fit the correlator data in order to extract fit parameters, in the following we display effective mass plots so the reader can visualize the data. the single-particle effective mass is constructed as aeeff jpc ¼ log � cj pc i;j ðtÞ cj pc i;j ðt þ Þ � ð Þ ¼aejpc þ zi z j;� zi z j;� e−ðe −e Þtð −e−ðe −e ÞÞþ�� ð Þ ⟶ t→∞ aejpc: ð Þ as can be inferred from eq. ( ), the greater the mass gap e − e or the larger the ground state overlap z , the quicker aeeff jpc converges to a plateau, which gives aejpc. the ηb and Υ effective masses are shown in fig. , where the returned fitted ground-state energy from the correlator fits is also shown overlaid in black. the large difference in energy betweentheη b (Υ ) andthegroundstateηb (Υ)meansthatthe effective mass plots fall rapidly to a plateau given by the ground-state energy, indicating that the fit to the correlator data extracts the ground-state energy precisely. also evident from the effective mass plot is the constant signal to noise in the ηb data, as might be expected from straightforward application of the parisi-lepage arguments [ , ] for noise growth in a system where all the quarks are the same and no þþ bound tetraquark exists. the argument specifies that the noise of the two-point correlator should behave like expfðejpc − egs= Þtg where ejpc is the lowest energy eigenstate of the bottomonium operator ojpc con- structed to have the quantum numbers jpc and egs is the lowest energy eigenstate of the mean squared correlator which controls the noise. thus, it would be surprising if a tetraquark candidate did exist below the ηb threshold from thelatticeperspectivealoneasthenegs < eηb andthenoise of the ηb data would grow exponentially. however, the lattice calculation still needs to be performed for a conclusive statement to be made about the existence of this tetraquark candidate since the parisi-lepage arguments do not allow for raw crossed wick contractions that wouldcontribute toeither the full two-meson or tetraquark correlator. lattice correlators are affected by both the discrete nature of the space-time lattice and separately by its finite volume. each has a separate but calculable effect on the extracted lattice energies. corrections in energies due to discretization effects are proportional to ak, where k depends on the level of improvement. here systematic discretization errors are reduced to α sa by the improvements made, as for those studies listed in sec. iii b, and we expect this to be small enough to have little impact. we can assess this from our results with different values of the lattice spacing. finite-volume effects for single-particle energies (arising from the lightest particle in the sea propagating around the spatial boundaries) are known to behave like expð−amπnsÞ [ ] and are not appreciable for the ensembles used here which have amπns ≈ [ ]. in fact, ns on set and differ by a factor of , giving a basic test of volume dependence. however, finite-volume interactions can shift a two-particle energy by an amount that depends on the infinite-volume scattering matrix. further, these shifts are nontrivial to parameterise (see for example [ – ]). as the specific purpose of this study is to search for a hypothetical tetraquark bound state below the lowest threshold, we do not attempt to quantify these finite-volume interactions. equation ( ) describes the nonrelativistic two-particle contribution to the correlator after t ¼ fm (as shown in fig. . the effective mass plot for the ηb and Υ on the superfine ensemble (set listed in table iii). the effective mass plots on the other ensembles are qualitatively identical. these arise in lattice two-meson calculations when a rela- tivistic formulation of valence quark is used due to one of the mesons propagating forward in time while the other propagates around the temporal boundary backwards in time [ ]. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - appendix a). in this case, because of the additional =t time dependence, the effective mass formula for these contributions differs from their single-particle counterparts. removing the leading order time dependence yields an effective mass defined as aeeff;t jpc ¼ log � t cj pc i;j ðtÞ ðt þ Þ cjpci;j ðt þ Þ � : ð Þ for the þþ, þ− and þþ operators that are constructed, if a stable tetraquark exists below the ηb, ηb þ Υ or Υ thresholds then it would show up as the ground state of each correlator and hence also in the effective masses. otherwise, each threshold would be the lowest energy eigenstate. higher energy states also appear in each correlator. for example, the Υ and ηbη b in the þþ case, the Υη b in the þ− and the ΥΥ and χb χb ð pÞ in the þþ. of these, if no tetraquark state is present, only the Υ in the þþ might be noticeable while studying the ground state, as it is oð Þ mev above the ηb. all other excited states have similar energy differences to those appearing in the ηb=Υ effective masses shown in fig. , which rapidly falls to the ground state. it is helpful at this stage to generate mock correlator data to illustrate how we might expect the b̄b̄bb correlator results to behave in the presence or absence of a low-lying tetraquark state (neglecting two-particle finite-volume effects). using the extracted lattice ηb and Υ masses, we can compute the noninteracting ηb and Υ thresholds on our ensembles. further, for a fixed value of z x , we can also compute their leading order two-particle contribution to the correlator from eq. ( ). additionally we can infer the values of the noninteracting ηbη b and ΥΥ masses on our ensembles using the experimental pdg [ ] values as input in order to include their two-particle contributions in the mock correlator data also. further, in the þþ channel, if we assume a tetraquark bound state exists mev below the ηb threshold, for a fixed value of the tetraquarks non- perturbative overlap, z b, this hypothetical state’s contri- bution to the correlator is given by eq. ( ). then, given the effective mass formula defined in eq. ( ), for each different choice of the nonperturbative coefficients we can generate a separate effective mass curve. in practice, we choose different values of the coefficients from a normal distribution with zero mean and unit variance. figure shows such a plot for the superfine ensemble (set in table iii) where the solid blue curves represent different values of the normally distributed coefficients. as the nonperturbative coefficients show up through the ratio z x =z b in the effective mass formula, analogously to eq. ( ), once the energy difference e − e is set the effective mass is only sensitive to the relative size of the tetraquark overlap to that of the lowest threshold (once the contribution of excited states has become negligible). with this knowledge, the lower red dotted curve gives mock data in the situation where there is only a new state present in the correlator data (z x ¼ ), the middle red dashed curve indicates the case when the tetraquark and two-meson states have the same value of coefficient (z x ¼ z b), while the upper dot-dashed red curve is the mock data in the case where there is no new state in the data (z b ¼ ). the blue curves below the middle red one have a larger overlap onto the new state while those above have an increasingly vanishing one. with our overconstrained color-spin basis of s-wave operators at least one operator should have an appreciable overlap onto a tetraquark state below threshold (if it exists) and, as illustrated by the mock data, give an easy/clean signal similar to the middle red dashed curve where the effective mass drops below the ηb threshold. even though fig. is mock data, the upper red curve with no tetraquark state present looks very like the real data shown in figs. and . one important point to note is the additional factor of =t appearing in the two-particle contribution in eq. ( ) relative to the single-particle one in eq. ( ). this factor suppresses the two-particle contribution relative to the single-particle state; e.g., t ¼ gives a suppression of the two-particle state of ð . Þ . . this is one reason why the middle red dashed curve has a particularly rapid fall to the new state which lies only mev below the ηb [compared to fig. (d) where the Υ is oð Þ mev above the ηb]. overall this effect would produce an enhancement of the stable tetraquark state if it exists. further, while we used the superfine ensemble for illustrative purposes, the other ensembles with larger lattice spacings have similar features but with less temporal resolution due to the larger numerical value of the lattice spacing. fig. . assuming a tetraquark exists mev below the ηb threshold, different normally distributed couplings in b̄b̄bb correlator mock data produce different effective mass curves on the superfine ensemble (set listed in table iii) as described in the text. the smallest binding of a below threshold b̄b̄bb tetraquark from the phenomenological studies (which are shown in fig. ) was mev [ ]. hughes, eichten, and davies phys. rev. d , ( ) - if one is searching for a bound state below threshold then both single- and two-particle contributions appear in the correlator and one may use the single-particle effective mass formula given in eq. ( ) in order to highlight the bound ground-state mass (as done in the mock data above). however if no bound state exists in the data, which we do not know a priori, then not removing the =t dependence from the two-particle contributions has an important effect: an additional factor of . logð þ =tÞ is introduced into the effective mass formula in eq. ( ), giving a contami- nation that vanishes slowly as t → ∞. this would produce a confusing picture of what is actually contributing. the two-particle effective mass formula eq. ( ) removes this contribution. in the results to be reported now, we overlay both single- and two-particle effective masses on the same plot for the reader’s convenience. we generate the b̄b̄bb correlator data for the operators given in table v using the ensembles listed in table iii and fit these data simultaneously with the bottomonium meson data to include correlations between data sets. all the b̄b̄bb data within a specific irrep and those which are unrelated by a fierz relation are fit using eq. ( ) for the two-particle contributions and eq. ( ) for a hypothetical tetraquark state below threshold. the mean of the prior energy of the ηb, ηb þ Υ and Υ thresholds is roughly estimated based on the effective masses and then given a suitably wide prior width of mev while a tetraquark state prior energy is taken to be ( ) mev below each threshold. as can be seen in fig. , since the data plateau to the noninteracting ηb threshold, no energy eigenstate is found below this thresh- old and variations of the tetraquark prior energy are insignificant. similar behavior is seen with the other quantum numbers. (a) (c) (d) (b) fig. . the b̄b̄bb effective masses for the þþ ðm ; m Þ → ðm ; m Þ correlators where m , m are the ηb or Υ. eeff and eeff;t are the single- and two-particle effective masses defined in eqs. ( ) and ( ) respectively. the mesons are separated by a distance rx in the x-direction when constructing the two-meson interpolating operator as given in eq. ( ). gray points are not used when fitting the data (cf., appendix a). simultaneously fitting data sets related by a fierz identity would mean the correlation matrix would have a zero eigenvalue and thus not be invertable for use in a least-squares minimization. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - again, while we fit the correlator data in order to extract particle energies, so that the reader can visualize these data, we display effective mass plots on the different ensembles. the superfine ensemble (set ) þþ two-meson effective masses are shown in figs. , while the þþ diquark- antidiquark effective masses are given in fig. , the physical coarse (set ) þ− two-meson and diquark-anti- diquark effective masses in fig. and the fine (set ) þþ two-meson and diquark-antidiquark effective masses sub- duced into the t lattice irrep are shown in fig. . each plot has the fitted ground-state energy overlaid in black for comparison. the þþ subduced into the e irrep is similar to the t case. further, the behavior of the lattice data on all ensembles is qualitatively similar to those shown. the extracted ground-state energies in each channel are given in table vi and a comparison of the energies is shown in graphical form in fig. . it should also be noted that the numerical value of the effective mass (shift) plateau in two-hadron correlators has been shown, in certain cases, to be sensitive to the choice of interpolating operators [ , ]. there, the authors found that when the noise growth in the correlator data restricts the study of effective masses to a maximum propagation time of approximately fm, fake plateaus can appear. these fake plateaus can be a consequence of different choices of source and sink (smeared) operators: this can cause a negative sign in the z term in the effective mass formula eq. ( ) and a dip below threshold can appear for a short time range which can be misinterpreted as a bound state. wall sources were shown to be particularly prone to this behavior of producing a “false dip” and obtaining an appreciably different plateau than a gaussian source. here we only use local quark sources. in addition, the elastic scattering states can also have a depend- ence on the choice of operator, which can cause a slow decay to the ground state andmimic a slowly varying effective mass that can be mistaken for a plateau over a short time range. as noted in these studies, a necessary check for a real effective mass plateau when using different source and sink operators istheconvergenceofalldatatoasingleplateauattimeslarger than approximately fm. as we separate the operators by rx ¼ , and lattice units (as described in sec. iii c) and propagate to t > fm, this is a consistency check we satisfy. a few notable features of the b̄b̄bb effective mass plots are evident. first and foremost, no value of the fig. . the b̄b̄bb effective masses for the þþ diquark- antidiquark ̄ × ̄ and × ̄ correlators. eeff and eeff;t are the single- and two-particle effective masses defined in eqs. ( ) and ( ) respectively. the diquarks are separated by a distance rx in the x-direction when constructing the diquark-antidiquark inter- polating operator as given in eq. ( ). fig. . the b̄b̄bb effective masses for the þ− Υηb and diquark-antidiquark ̄ × ̄ correlators. eeff and eeff;t are the single- and two-particle effective masses defined in eqs. ( ) and ( ) respectively. hughes, eichten, and davies phys. rev. d , ( ) - effective mass is observed below the lowest noninteracting bottomonium-pair threshold in any channel, in line with what one would expect if no stable tetraquark candidate existed below threshold. indeed, the b̄b̄bb effective mass plots are strikingly similar to the upper dot-dashed curve in the mock data in fig. where no bound tetraquark state is present. additionally, the ηb → ηb effective mass shown in fig. (a) plateaus very early due to the larger overlap onto the ηb threshold, while the þþ Υ → Υ effective mass shown in fig. (d) falls more slowly to the ηb threshold due to the larger overlap onto the nearby Υ threshold. the cross correlators ηb → Υ show how the different operators converge to a single plateau at a time greater than t ≈ fm, a necessity for a true plateau as discussed above. the local diquark-antidiquark þþ corre- lator data are a linear combination of the ηb and Υ two- meson data, related by the fierz identities given in table ii, and the effective masses shown in fig. reflect this. it is empirically observed that separating the diquark from the antidiquark by too large a distance rx results in larger noise due to the separation of color sources. the þ− Υηb and diquark-antidiquark effective masses are shown in fig. , where the noise starts to increase after t ≈ fm due to the parisi-lepage argument mentioned above with the noise being set by at least the ηb threshold. based on this, one would also expect the signal to noise to be worse for the þþ data, which is also evident from the correlator data subduced into the t irrep shown in fig. . as set has physical ml=ms corresponding to a pion mass of oð Þ mev, while the other ensembles have nonphysical ml=ms corresponding to pion masses of oð Þ mev [ ], no sensitivity to light sea quarks is observed. this would be expected from the smallness of the van-der-waals potential generated by the two-pion exchange between two s bottomonium mesons [ ]. as can be seen in figs. and , the þþ ground state obtained from the lattice is slightly higher than that of the noninteracting threshold. however, this is the state which has the largest signal to noise, restricting the data to shorter time regions and it is possible that we are sensitive to the same aforementioned issue of a slowly varying fake plateau. alternatively, this positive shift in the two-particle energy could potentially indicate appreciable infinite-volume continuum scattering arising from finite-volume interactions [ ], but quantify- ing these phase shifts is outside the remit of this study. regardless, these effects do not indicate that a bound tetraquark state exists in this channel. for illustration purposes, we also show the effective masses of the individual wick contractions contributing to the ηb → ηb correlator in fig. . as is evident, in each individual wick contraction the effective mass drops below the ηb threshold but then rises slowly to threshold. however, importantly, when all wick contractions are added together to yield the full correlator [shown fig. (a)] the effective mass falls rapidly to threshold from above. this behavior is discussed further in sec. vi. after analyzing all our data, as hinted by the effective mass plots, there is no indication of a bound tetraquark state below the noninteracting thresholds on any ensemble, as fig. . the b̄b̄bb effective masses for the þþ ΥΥ and diquark- antidiquark ̄ × ̄ correlators subduced into the t irrep. e eff and eeff;t are the single- and two-particle effective masses defined in eqs. ( ) and ( ) respectively. table vi. the ground-state static masses extracted from the lattice b̄b̄bb correlator data as described in the text. set amηb amΥ am þþ am þ− am þþt am þþe . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) . ( ) searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - shown in fig. . we see no evidence of any change in the ground-state energies (with respect to the thresholds) as we vary lattice spacing or sea quark masses. searching for a new tetraquark candidate has at least a two-dimensional parameter space: the hypothetical state would have an energy and also an overlap onto a specific operator. using the lattice data presented here, we can determine a relationship between these parameters. assuming that a tetraquark does exist below the lowest bottomonium-pair threshold in our data, at a certain time t� the correlator can be modeled with a two-state ansatz. specifically for the þþ channel, given that the tetraquark has an energy e b and an overlap z b onto a particular operator, at a large enough time the only other appreciable contribution will come from the higher ηb threshold which has an overlap z ηb with the same operator. in this case the correlator is given by cðt�Þ ¼ z be−ae bt � þ z ηbe −ae ηb t � � amηb πt� � : ð Þ using this ansatz in the effective mass formula eq. ( ) and rewriting the equation in terms of the nonperturbative overlaps yields the constraint z b z ηb ¼ � − ð t�t�þ Þ expðaeeffðt�Þ − ae ηbÞ expðaeeffðt�Þ − ae bÞ − � × e−aΔet � � amηb πt� � ð Þ with aΔe ¼ ae ηb − ae b > . as can be seen, if the tetraquark is not observed by a time t� then the overlap onto this new state must be (at least) exponentially suppressed with the binding of the tetraquark state, e.g., with −Δe. this point illustrates that if a tetraquark did exist with e b < e ηb then it is possible that it was not observed in our data because z b ≈ within statistical precision. in this scenario, we can use the constraint eq. ( ) to estimate an upper bound on the magnitude of the overlaps given that no clear evidence of the tetraquark is observed within our statistical precision. the needed inputs for the constraint include the value of t� where the two-state ansatz is valid, aeeffðt�Þ from correlator data constructed with a specific operator, as well as ae ηb ¼ amηb. for the local oðηb;ηbÞ operator on the a ¼ . fm ensemble, by examining fig. (a), a choice of t� ¼ ensures that the two-state ansatz is valid (given the long plateau at the ηb threshold). here, aeeffðt� ¼ Þ ¼ . ð Þ can also be precisely obtained. the value of amηb, given in table vi, is found from the ηb-meson data. then, using this data in the constraint, for a certain choice of e b, a numerical value fig. . a summary of the b̄b̄bb ground-state energies with the lowest noninteracting bottomonium-pair threshold subtracted, across the different lattice ensembles listed in table iii, statistical error only. note, as shown in table iii, fewer configurations were used on the a ¼ . fm ensemble than on the others. fig. . the individual wick contraction effective masses of the ηb → ηb correlators. the upper figure is the direct and the lower is the xchange contraction [each shown diagrammatically infigs. (a)and (b)]. eeff and eeff;t arethesingle-and two-particle effective masses defined in eqs. ( ) and ( ) respectively. hughes, eichten, and davies phys. rev. d , ( ) - of the ratio of overlaps is found such that it is consistent with within its small σ statistical error. any value of the ratio of overlaps larger than this σ error is inconsistent, at this level of confidence, with our data observing a tetra- quark at this value of e b. we use this model to estimate how small the hypo- thetical tetraquark overlap would need to be so that the tetraquark was not observed within our statistical pre- cision. a σ, σ and σ exclusion plot of the parameter space is given in fig. . as the input data into the constraint has a long propagation time past t� > fm and a statistically precise value of aeeffðt�Þ which does not fall below the threshold, a significant amount of param- eter space is excluded. it should be understood that this figure is only valid for a particular operator in a certain channel. the given þþ channel in fig. excludes the largest amount of parameter space as it is the most statistically precise. also fig. is constructed from data on the superfine ensemble alone, where discretiza- tion effects are smallest and would not change the quantitative behavior significantly. to conclude this section, we find no evidence of a stable tetraquark candidate below the noninteracting thresholds by studying a full s-wave color-spin basis of qcd operators. in the next section we perform an exploratory and complementary study of an alternative approach to ensure the robustness of our conclusions. v. nrqcd with a harmonic oscillator potential a stable tetraquark state in the þþ, þ− and þþ channels would overlap with the full basis of s-wave color-spin operators utilized above. in this section, we go one additional step by exploring an alternative approach in order to further investigate the possibility of a tetraquark state. adding a central confining potential to the quark interactions can produce a more deeply bound tetraquark relative to the threshold as the strength of this interaction is increased (as we see below). furthermore, an appropriate choice of additional interaction can reduce the fiducial volume of the lattice and thus thin the allowed discrete momenta states of the two-meson degrees of freedom. adding an external attractive scalar central potential to the qcd interactions yields these desired effects. the harmonic oscillator potential is a particularly suitable choice of scalar interaction between quarks. for a particle of mass m at position x away from the center x the potential is just κr = ≡ κjx − x j = . defining ω ¼ ffiffiffiffiffiffiffiffiffiffiffiffiffi ðκ=mÞ p , the ground-state energy and wave function are e ¼ ω= and ψðrÞ ¼ c exp ð−mωr = Þ. additionally, the separabil- ity of the combined qcd and harmonic oscillator potential into total and relative coordinates ensures that solutions of multiquark systems can be split into two parts with the total coordinate piece analytically solvable. this follows from the nature of the harmonic oscillator potential. thus we expect that for small values of ω the ground state for ηb mesons is approximately mηbðωÞ þ ω. the ω term comes from two color-singlet ηb mesons in the harmonic oscillator potential and the mass of the ηb is shifted slightly from the value at ω ¼ because of the additional harmonic oscillator inter- action combined with the qcd interactions that bind the two heavy quarks into a ηb. however, for a compact tetraquark state the mass would be mðb̄b̄bbÞðωÞ þ ω= , as there is only one color-singlet state in the central harmonic oscillator potential ( ω= ) and if the tetraquark state is also a compact state (on the scale of ηb and much less than the effective lattice volume), then its mass will also receive only a modest positive correction due to ω. hence if there were a tetraquark state near threshold then this additional interaction could drive it further below threshold, giving a much cleaner and distinct signal for the tetraquark candidate in our calculation. as the potential model framework describing the ηb has been largely successful, we can use this framework as a general guide for the exploratory nonperturbative lattice calculation when including the harmonic oscillator potential. of course, we are mainly interested in qcd (and not the harmonic oscillator) and, as such, if we do find a stable tetraquark state when including the harmonic oscillator potential then we must take the ω → limit. thus, the objective of this section is to determine if a stable tetraquark state exists when the quarks are exposed to an auxiliary potential (which could push the tetraquark increasingly lower than the threshold) and if it does, whether it will survive the qcd limit. fig. . the excluded region for the ratio of tetraquark/ ηb overlaps, z b=z ηb, onto the oðηb;ηbÞ operator, assuming a tetraquark with mass, e b, lying below the ηb threshold, e ηb. the red hashed region is excluded at σ by the data as described in the text. the σ − σ and σ − σ exclusion bands are also shown for reference. defining r ¼ jx − x j and rcm ¼ ððx þ x Þ= − x Þ, we can separate κ½ðx − x Þ þ ðx − x Þ �= into relative and center-of-mass coordinates ½ðκ= Þr þ ð κÞr cm�= . for sufficiently small ω the shift in ηb is directly related to the rms radius of the ηb state since from perturbation theory it is given by hηbðω ¼ Þjkr = jηbðω ¼ Þi. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - the harmonic oscillator potential is defined as δhho ¼ mbω jx − x j ð Þ where the quarks are pulled towards the fixed point x with a strength ω. we choose x to be the same position as the source. intuitively, as the quarks/ηb’s start to propagate further away from the source, the harmonic oscillator potential pulls them closer together. in turn, this restricts the quarks/ηb’s to be in a certain volume. first, it is necessary to determine which volumes the quarks/ηb’s are confined into by the addition of the harmonic oscillator potential. the root mean square dis- tance, rrms, gives an indication of this. we determine the rrms of the ηb based on solutions of the schrodinger equation using a cornell potential. the matthieu equation can describe the behavior of two free ηb’s in a harmonic oscillator potential on a periodic box, and the solutions of which can yield rrms for the ηb state. the results from such a calculation are plotted in fig. . based on this, in order to confine the quarks sufficiently so that the two ηb’s overlap, and also to study thedependence on ω, values of ω ¼ ð ; ; ; Þ mev and ω ¼ ð ; ; ; Þ mev are chosen for the lattice ensembles called set and set in table iii. in lattice units, the simulated values of κ= ¼ ðambÞðaωÞ = are ( . , . , . , . ) and ( . , . , . , . ) respectively. the harmonic oscillator is implemented through a minor modification of the nrqcd evolution equations via e−a ~h ¼ � − aδhho l � l e−ah � − aδhho l � l ð Þ where e−ah is the purely nrqcd evolution equation defined in eq. ( ). this implementation was chosen so that the evolution equation is still time-reversal symmetric. here, l is a stability parameter akin to n in eq. ( ) which is used to prevent possible numerical instabilities [ ]. values of l ¼ and were chosen for the calculations on set and respectively. following these details, we are now able to present results from the nonperturbative lattice calculations. a. numerical results all correlator data from set and discussed in sec. iv were generated again with the inclusion of the harmonic oscillator potential at the four different ω values given above. the harmonic oscillator alters both the single- and two-particle contributions to the correlator so that they become (as derived in appendix b) dependent on ω as cj pc i;j ðt; ωÞ ¼ x n zinz j;� n ð þ e− ωtÞ e−ðmðωÞnþ ωÞt ð Þ cj pc i;j ðt; ωÞ ¼ x x zix z j;� x � ωμrπ − − e− ωt � e−ðm s ðωÞþms ðωÞþ ωÞt þ � � � : ð Þ first, fig. shows the effective masses, as defined in eq. ( ), of the ηb when including the harmonic oscillator. also overlaid are the effective masses when removing the þ e− ωt dependence to enable a better comparison with the data when no harmonic oscillator is included. as can be seen, the dip in the harmonic oscillator effective masses is from this additional time dependence. physically, this can be understood to be due to the b-quarks travelling non- relativistically and so it takes time for the harmonic oscillator to have an effect. fig. . the root mean square distance rrms of the ηb and the ηb as a function of the harmonic oscillator strength calculated from a potential model with the different ensemble parameters listed in table iii as discussed in the text. fig. . the effective mass plot for the ηb when including the harmonic oscillator potential on set . eeff is given by eq. ( ) while eeff;ξ removes the leading þ e− ωt dependence from the correlator ( ) to enable a better comparison with the data when no harmonic oscillator potential is included. in a periodic box of length l the harmonic oscillator is also periodic. the potential form is − αs r þ rb with αs ¼ . , b ¼ . gev and reduced mass . gev. hughes, eichten, and davies phys. rev. d , ( ) - the ηb correlator data when including the harmonic oscillator potential are fit to the functional form given by eq. ( ) in order to extract the lowest energy eigenstate mðωÞηb þ ω= from the asymptotic behavior. we show the fitted result overlaid on the effective mass plot in fig. . as before, the long plateau indicates that the ground state will be extracted accurately. to compare to the potential model predictions, we subtract the ηb mass with no harmonic oscillator included [mðω ¼ Þηb] and then plot the energy differences against ω, as shown in fig. . good qualitative agreement between the lattice results and the potential model predictions is observed. forthe b̄b̄bb system,weshow the þþ effective masseson set in fig. . it is evident that the þþ and the ηb data contain more noise when a harmonic oscillator potential is included. while fitting the data to the form in eq. ( ) can be performed, it is not necessary as the purpose of this fig. . the lattice ηb energy mðωÞηb þ ω= when including the harmonic oscillator potential with mðω ¼ Þηb subtracted compared to the model predictions as discussed in the text. (a) (b) (c) (d) fig. . the b̄b̄bb effective masses for the þþ correlators when including the harmonic oscillator potential on set . eeff is given by eq. ( ), while eeff;‡ removes the leading − e− ωt dependence from the correlator ( ) to enable a better comparison with the data when no harmonic oscillator potential is included. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - exploratory work is to determine if a stable tetraquark exists when ω ≠ . as can be seen, there is no fall below the ηb threshold for any valueofω. similarbehavior isseen withthe data on set . we show the effective masses for the individual direct and xchange wick contractions of the ηb → ηb corre- lator in fig. . as before, the effective masses of the individual wick contractions drop below the ηb threshold, even though importantly, when added together to yield the full correlator shown in fig. (a) the effective mass is always above threshold. as this was also seen in the pure nrqcd data shown in sec. iv, it may be a problematic feature of models that utilize a phenomenologically moti- vated four-body potential for this system. to conclude this section, despite adding an auxiliary potential into the qcd interactions that should push a near threshold tetraquark candidate increasingly lower we find no indication of any state below the ηb threshold. the conclusions of this section then agree with those of sec. iv. vi. discussion and conclusions in this work we have studied the low-lying spectrum of the b̄b̄bb system using the first-principles lattice nonrelativistic qcd methodology in order to search for a stable tetraquark state below the lowest noninteracting bottomonium-pair threshold in three different channels: the þþ which couples to the ηb and Υ, the þ− which couples to Υηb and the þþ which couples to Υ. in sec. iii we describe our numerical methodology. four gluon ensembles were employed with lattice spacings ranging from a ¼ . – . fm, and one ensemble which has physical light-quark masses. all ensem- bles have u, d, s and c quarks in the sea. in sec. iv we presented the majority of the results in this work. here, we determined the lowest energy eigenstate of the b̄b̄bb system with the quantum numbers þþ, þ− and þþ using an overconstrained s-wave color/spin basis (arising fromfierzrelations betweenthediquark-antidiquark and two-meson systems as shown in table ii). we did not observe any state below the lowest noninteracting bottomo- nium-pair threshold in any channel, as can be seen in figs. – , and a summary of our results from this section is given in fig. . in sec. v, to ensure the robustness of our conclusions, we performed an exploratory calculation of a novel method which added an auxiliary scalar potential into the qcd interactions with the objective of pushing a near threshold tetraquark increasingly lower than the threshold. this would give a more distinct and cleaner signal for its presence in our calculation. the harmonic oscillator was found to be a suitable central scalar potential. for the ηb-meson with this potential, we first verified agreement between the non- perturbative lattice calculations and a potential model (as shown in fig. ) and then used this potential model as a general guide to choose multiple appropriate values of the potential strength. despite studying the b̄b̄bb system with this additional scalar potential on the lattice, no indication of the qcd tetraquark was observed. this work is the only first-principles study of the low- lying b̄b̄bb spectrum in the literature. however, there are others which utilize different methodologies. for example, ref. [ ] predicts the tetraquark mass by solving the two- particle schrodinger equation with a phenomenologically motivated nonconfining potential between the pointlike diquark and antidiquark, and finds a þþ; þ− and þþ tetraquark to be bound by , and mev respectively. the authors of [ ] used a diquark model including a confining linear potential, but neglected spin effects, and found a þþ tetraquark to be bound by mev. however, it has also been found that the root mean square distance fig. . the effective masses for the individual ηb → ηb wick contraction correlator data when including a harmonic oscillator potential on set . the upper figure is the direct and the lower is the xchange contraction [each shown diagram- matically in figs. (a) and (b)]. a model in which the diquarks are taken to be fundamental particles cannot determine the two-meson threshold from the schrodinger equation because the diquarks cannot recombine into mesons. thus, the experimental meson masses [ ] are used to determine the lowest threshold. hughes, eichten, and davies phys. rev. d , ( ) - between the diquark and antidiquark inside the tetraquark in this model is similar in magnitude to the distance between the quarks inside each diquark [ ]. consequently, such an approach is internally inconsistent. more recently, [ ] used a hamiltonian including only spin-spin interactions medi- ated by a one-gluon exchange. here, all other effects such as the chromoelectric interactions, color confinement and b- quark mass need to be set separately. the authors set these additional contributions in two ways: by estimating the effects using an effective heavy quark [ ] or by using the experimental meson masses as input. in this way, the authors find that the tetraquark state could be either below the ηb threshold or lie in between the ηb and Υ thresholds (where in both cases the thresholds were determined using the experimental meson masses). in [ ] the author also uses a model including only chromomagnetic interactions and finds an unbound tetraquark. within the qcd sum-rules framework, [ ] finds a tetraquark candidate approximately mev below the experimental ηb threshold while [ ] finds a tetraquark lying in between the experimental ηb and Υ thresholds. using phenomenological arguments, [ ] also finds a tetraquark candidate lying in between the thresholds. indeed, in the limit of very heavy quarks where the force proceeds through one-gluon exchange containing only color-coulomb contributions (safely neglecting spin and long-distance effects), the authors of [ ] used a variational methodology to determine that a bound tetra- quark exists for a qqq̄ q̄ system when mq=mq ≲ . (where both mq and mq are heavy relative to Λqcd). however, if mq=mq is varied and the tetraquark becomes unbound, then as the free two-meson eigenstate becomes the ground state of the system this numerical methodology has an increasingly slow convergence to a solution [ ] (being numerically ill posed) due to a redundant degree of freedom in the minimization procedure. indeed [ ] indicates that for mq=mq ¼ the solution is unstable, a hint that no bound tetraquark exists for all identical quarks in the very heavy mass limit. the authors of [ ] assume that the b-quark is sufficiently heavy to use the one-gluon exchange with only color-coulomb contributions, and by also neglecting the mixing between different color components of the × potential matrix, find a tetraquark bound by ( ) mev (by using the experimental ηb mass to determine the threshold). in an orthogonal direction to the above work, the authors of [ ] only include a linear string contribution in the one- gluon exchange (neglecting spin effects and the appreciable short-distance coulomb contributions), and without mixing between the different color components of the potential matrix, find a bound tetraquark when mq=mq ¼ . however, in subsequent work [ , ], by modelling the aforementioned mixing they concluded that no bound tetraquark exists. perhaps the most sophisticated non first-principles methodology used to study the four-body b̄b̄bb tetraquark is the diffusion monte carlo method utilized by [ ]. here, one determines the ground state of a phenomenologically motivated hamiltonian by solving the schrodinger equation and examining the stability ofp ne −ðen−e ÞtΨnðxÞ to determine e , where en (Ψn) is the n-th energy-eigenstate (eigenfunction). the authors include boththe color-coulomband linear contributionsin thegluon exchange but neglect the mixing between the different color components in the potential matrix, and find a stable tetraquark candidate mev below the ηb threshold (determined from the experimental meson mass). consequently, there is no study in the literature which is not from first principles that includes all the appreciable effects relevant for the bbb̄b̄ system: treating the bottom quarks as fundamental particles, including both short- and long-distance effects in the gluon exchange and including the mixing between the different color components in the × potential matrix. it should be emphasized however that these studies, unlike ours, are not from first principles and thus have an unquantifiable systematic error associated with the choice of four-body potential. to emphasize this further, thinking of each wick contraction (shown diagrammatically in fig. ) as a different potential contributing to the qcd dynamics, then only studying a subset of these interactions can change the energies of states. this can lead to the misidentification of a new state below threshold. for example, the effective masses of the individual wick contractions contributing to the ηb → ηb correlator are shown in fig. . as is evident there, in each individual wick contraction the effective mass drops below the ηb threshold but rises slowly to threshold even though when all wick contractions are added together to yield the full correlator [shown fig. (a)] the effective mass falls rapidly to threshold from above. this behavior is even more pronounced in the data with the additional scalar potential, shown in fig. , possibly indicating that this may be a problematic feature of models that utilize a phenomeno- logically motivated four-body potential: a subset of the interactions show behavior that may be misinterpreted as a bound state below threshold, while when all interactions are included no bound state is seen. particularly, the slow rise to threshold from below could make the diffusion monte carlo method practically difficult due to the slowly varying stability condition combined with the fact that a long evolution time (greater than fm) is necessary. in conclusion, we find no evidence of a b̄b̄bb tetraquark with a mass below the lowest noninteracting bottomonium- pair thresholds in the þþ, þ− or þþ channels. we give a constraint in eq. ( ) that future phenomenological models must satisfy if such qcd states are postulated. for the þþ channel, we use this constraint to estimate how small the nonperturbative overlap of the hypothetical tetraquark (onto a particular operator) would need to be, relative to the ηb, so that it was not observed within our statistical precision. a σ, σ and σ exclusion plot of the parameter space is shown in fig. , and discussed in sec. iv. as we searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - have propagation times longer than fm and statistically precise data, we can exclude all but the most finely tuned parameter space. our lattice results then rule out the phenomenological models discussed above that predict a tetraquark below the lowest bottomonium-pair thresholds which have a value of nonperturbative overlap that is excluded by fig. . a comparison of these results with ours is shown in fig. . further studies of possible heavy tetraquark channels that includeorbital angular momentum either between themesons in the tetraquark or between the quarks in the meson could be performed with the methodology used here. similarly one could also study whether stable c̄c̄cc, b̄c̄bc or b̄b̄cc tetraquarks exist or not. additionally, two-hadron systems receive a finite-volume energy shift which depends on the infinite-volume scattering amplitude which is nontrivial to parametrize. here we do not calculate these finite-volume energy shifts. doing so in a more extended study would allow statements to be made about the existence of resonant tetraquark states above the lowest thresholds, that likely do exist in nature. quantifying these shifts would be an exciting avenue for future work. finally, recent work based on heavy-quark symmetry [ ] and phenomenological arguments [ ] indicates that a jp ¼ þ b̄b̄ud tetraquark is stable in qcd. in fact, by extracting a potential from the lattice in the static heavy-quark limit and solving the schrodinger equation [ – ] also find binding in this channel. initial lattice calculations hint that such a state exists [ ], but calcu- lations are difficult because of a signal-to-noise problem for heavy-light states [ ]. lattice qcd calculations in this direction are essential for a conclusive first-principles statement to be made and to give further motivation for a targeted experimental search for these tetraquark configurations of nature. acknowledgments we would like to thank william bardeen and zhen liu for the many insightful discussions on tetraquarks, as well as gavin cheung who in addition gave guidance on the tetraquark implementation. we are also grateful to the milc collaboration for the use of their gauge configura- tions. this manuscript has been authored by fermi research alliance, llc under contract no. de-ac - ch with the u.s. department of energy, office of science, office of high energy physics. the united states government retains and the publisher, by accepting the article for publication, acknowledges that the united states government retains a nonexclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for united states government purposes. the results described here were obtained using the darwin supercomputer of the university of cambridge high performance computing service as part of the dirac facility jointly funded by stfc, the large facilities capital fund of united kingdom department of business, innovation and skills (bis), and the universities of cambridge and glasgow. appendix a: two-point correlator fit functions here we derive the nonrelativistic two-particle contri- bution to the correlator on our ensembles. to begin, the correlator is given in eq. ( ). for clarity, the i, j subscripts are dropped. the completeness relation for a two-hadron system is [ ] − − − e b − e ηb (mev) this calc. lattice qcd pheno. models clsz blo afgsz knr w wlcz † bln afgsz vvr ξ fig. . a comparison of our result for the b̄b̄bb ground-state energyinthe þþ channel(statisticalerroronly)andpredictionsfrom phenomenological models. the hatched region indicates the ex- clusion of a bound tetraquark with an energy e b subject to the value of its nonperturbative overlap as given in fig. . in this comparison, we take our ground-state energy obtained on the superfine ensemble (set in table iii) as a representative because it has the smallest discretization effects and the statistical error encompasses the results on the other ensembles as shown in fig. . the y-axis labels results from different phenomenological models [ – ] by last initial of authors and year of publication. an error is plotted if given in the reference. the two results from wlcz † differ by how the mass scale was set. the result vvr ξ finds no bound tetraquark and we indicate this by placing their result on threshold. it should be noted that although we focused on s-wave combinations of quarks, the channels we study also exclude certain combinationsoforbitalangularmomentumfromproducingabound tetraquark. for example, the þþ overlaps with Υ in an orbital angular momentum d-wave configuration. if this state produced a low-lying bound tetraquark itwould alsoshowupinourcalculation. hughes, eichten, and davies phys. rev. d , ( ) - i ¼ x x z d ptot ð πÞ d k ð πÞ eðx Þ jx ðptot;kÞihx ðptot;kÞj ða Þ where jx ðptot;kÞi ¼ jm ðkÞm ðptot − kÞi is a two-hadron state (with quantum numbers suppressed) and to avoid superfluous notation, we also set ptot ¼ . a key difference from the one-hadron system is the internal relative momen- tum, k, which contributes an additional three-integral. substituting the completeness relation eq. (a ) into the correlator eq. ( ) and performing the momentum conserv- ing integrals yields cðtÞ ¼ x x z d k ð πÞ zx ðkÞ e−eðx Þt ða Þ where zx ðkÞ is a nonperturbative coefficient. however, on a discrete finite volume the above integral over elastic states is replaced by a finite sum with km ∈ ð−ns= þ ; …; ; ns= Þ in units of ð π=ansÞ. in turn, for ptot ¼ , eq. (a ) becomes a sum over back-to-back hadronic states which have values of the discrete momenta that are equal in magnitude but opposite in direction. one can expand the two-particle energy using a nonrelativistic dispersion relation, appropriate since we are using nrqcd, as eðx Þ ¼ ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi m þ jkj q þ ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi m þ jkj q ða Þ ≈ ms þ ms þ jkj μr ða Þ wherewe have defined the static, kinetic and reduced masses by ms, mk and μr ¼ mk mk =ðmk þ mk Þ respectively. in a finite volume there is an additional contribution to eq. (a ) dependent on the infinite-volume scattering phase shift, which is discussed further below. equation (a ) also illustrates the density of back-to-back states on our ensem- bles. as an example, examining the a ¼ . fm ensemble, and taking mηb ¼ . ð Þ gev from the pdg [ ], the smallest allowed jkj = μr ≈ mev or . in lattice units with all other back-to-back states separated by multi- ples of this value. consequently, due to the bottomonium mass being large compared to the smallest allowed momen- tum, adjacent back-to-back states are sufficiently close in energy that fitting the momentum states as a discrete sum would require a vast set of correlators projected onto each separate jkj = μr (with the methodology used in [ ]). practically, this would be overly computationally expensive and instead, the fact that the states with k ≠ are related by the dispersion relation (and are not independent as the sum would assume) should be included. this can be achieved by first expanding the nonpertur- bative coefficient zx ðkÞ as a polynomial in jkj =μ r, as dictated by rotational symmetry and by ensuring the taylor coefficients have the same dimension, then keeping all terms needed to a certain precision. after this the correlator can be written as cðtÞ ¼ x x e−ðm s þms Þt x k �x∞ i¼ z l x jkj l μ lr � e− jkj μr t ða Þ ¼ x x e−ðm s þms Þt z π a −πa d k ð πÞ �x∞ i¼ z l x jkj l μ lr � e− jkj μr t ða Þ where going from the first to the second line we have replaced the finite sum by an integral. taking the limits of the integral to �∞ and performing the integrals over k analytically yields the fit function given in eq. ( ). once it is shown that it is possible to replace the finite sum by the indefinite integral within our statistical precision then it is valid to use the above fit function with our data. to do so, using spherical coordinates in eq. (a ), we define the quantities that we need to compare as iðlÞðtÞ ¼ μ lr z ∞ −∞ djkjjkj lþ e− jkj μr t; ða Þ dðlÞðtÞ ¼ μ lr x jkj jkj lþ e− jkj μr t: ða Þ the integrands of both are shown diagrammatically in fig. , where it is observed that due to the gaussian time dependence the peaks of the integrand move towards the origin withlarger t. as such,one objective istochoosea large enough t̂ such that a sufficient majority of the integrand is within the maximum momentum π=a. we can replace the discrete finite-volume fit function with its infinite-volume fig. . the integrands of the moments given in eq. (a ) at multiple times. the crosses represent the discrete finite-volume momentum contributions on the coarse (set ) ensemble as discussed in the text. due to the gaussian time dependence, the integrand peak moves towards the origin for larger times. searching for beauty-fully bound tetraquarks … phys. rev. d , ( ) - counterpart if the relative difference between them is less than our statistical errors. specifically if �� plmax l¼ z ;ðlÞiðlÞðtÞ − p∞l¼ z ;ðlÞdðlÞðtÞplmax l¼ z ;ðlÞiðlÞðtÞ �� ða Þ ≤ j plmaxl¼ z ;ðlÞiðlÞðtÞ − p∞l¼ z ;ðlÞdðlÞðtÞj jz ;ð Þið Þj ða Þ ≤ xlmax l¼ z ;ðlÞ z ;ð Þ jiðlÞðtÞ − dðlÞðtÞj ið Þ þ x∞ l¼lmaxþ z ;ðlÞ z ;ð Þ dðlÞðtÞ ið Þ ≤ xlmax l¼ jiðlÞðtÞ − dðlÞðtÞj ið Þ þ x∞ l¼lmaxþ dðlÞðtÞ ið Þ ða Þ ≤ δcðtÞ cðtÞ ða Þ where lmax is the maximum number of moments to be included in the fit function, the inequality in the second line holds as the moment integrands are positive (shown dia- grammatically in fig. ), in the third line the cauchy inequality has been used, and in the fourth line it is assumed that the leading moment gives the dominant contribution (z ;ðlÞ ≤ z ;ð Þ). studying eq. (a ) instead of eq. (a ) is a conservative option. each part of the first term in eq. (a ) represents how similar iðlÞðtÞ and dðlÞðtÞ need to be in order to be considered equivalent within statistical precision. this is shown in fig. . for a particular lmax, the second term represents when the higher moments look like noise within statistical precision, also shown in fig. . each figure was generated with the coarse ensemble parameters (listed as set in table iii) as this ensemble has the largest lattice spacing (and hence smallest π=a value—the upper limit on the integral of interest) and also the smallest ns (the number of discrete momenta used in the finite-volume sum). as such, the other ensembles give better approx- imations and studying set is conservative. overlaid on each plot is the smallest relative statistical error from the data on any ensemble. due to the constant signal-to-noise ratio, the number of configurations and the size of the lattice spacing, the smallest statistical error was the ηb correlator on the fine ensemble. only examining situations below this curve is the most conservative option for all data generated. as can be observed in fig. , the discrete finite- volume sums are well represented by the indefinite inte- grals. additionally, in order to neglect the higher moments within our statistical precision, a choice of t̂ ¼ fm and lmax ¼ is sufficient. expanding the finite-volume two-particle energy non- relativistically in eq. (a ) neglected a possible finite-volume energy shift which depends on the infinite-volume scattering amplitude. in the small scattering-length limit, the energy shift is known to be volume suppressed [ ]. the two- particle systems under study are in this limit as the ηb and Υ are compact due to the heavy-quark mass, with a size of . – . fm. as such, the low-momentum energy shifts are not expected to be appreciable given the large volume ensembles we employ. energy shifts in higher momentum states from eq. (a ) are exponentially suppressed due to the gaussian integral in eq. (a ). consequently, these too are not appreciable and no large influence of finite-volume energy shifts is seen (cf., the effective mass figures in sec. iv). quantifying these finite-volume scattering shifts is outside the remit of this study. regardless, the scattering shifts would be positive and push the finite-volume two-particle energy higher and not contribute to a misidentification of a bound tetraquark below the noninteracting threshold. appendix b: two-point correlator fit functions with a harmonic oscillator in the nonrelativistic limit the free propagator (to leading order) is Δðx; tÞ ¼ z d p ð πÞ exp ðip · xÞ exp � − � m þ p m � t � : ðb Þ the free two-meson propagator with ptot ¼ , both starting at common origin x ¼ ð ; Þ and ending at time t, is given by ~ΔðtÞ ¼ z d xΔ ðx; tÞΔ ðx; tÞ: ðb Þ using eq. (b ) in eq. (b ) produces the large-time behavior of the free two-meson propagator as fig. . the difference between the discrete finite-volume and infinite-volume continuum moments (upper) and which moments can be neglected compared to our statistical precision (lower) as discussed in the text. hughes, eichten, and davies phys. rev. d , ( ) - ~ΔðtÞ ¼ � μr πt � = e−ðm þm Þt: ðb Þ thisagreeswiththeleadingbehaviorderivedinappendixa. next, for the harmonic oscillator case, the one-dimensional hamiltonian is ∂ψ ∂t ¼ eψ ¼ − m ∂ ψ ∂x þ κ x ψ: ðb Þ solutions of this system can be related to the solutions of the mehler differential equation via ∂ϕ ∂~t ¼ ∂ ϕ ∂ρ − ρ ϕ ðb Þ with the identifications ω ¼ ffiffiffiffiffiffiffiffiffi κ=m p , t ¼ ~t=ω and r ¼ ðκmÞ− = ρ. the greens function (propagator) for the mehler differential equation is given by Δðρ ; ρ ; ~tÞ ¼ ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi π sinhð ~tÞ p exp � − coth ð ~tÞ ðρ þ ρ Þ þ cschð ~tÞρ ρ � : ðb Þ to normalize this propagator one can first compare the large t behavior of this solution with the known behavior of the harmonic oscillator propagator, limt→∞gðtÞ ¼ jΨð Þj e− ωt, where the wave function at the origin is given by Ψð Þ ¼ ðmω=πÞ = . as such, the harmonic oscillator solution is Δðx; ;tÞ ¼ ffiffiffiffiffiffiffi mω p ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi πsinhðωtÞ p exp � − mωx cothðωtÞ � : ðb Þ the three-dimensional solution can then be obtained using the separability of each spatial direction, so that the zero spatial-momentum single-particle correlator in a harmonic oscillator potential is given by z d xΔðx; ; tÞ ¼ � coshðωtÞ � = e−mt: ðb Þ finally, the equal mass two-particle propagator starting at a common origin x ¼ ð ; Þ and ending at a time t with ptot ¼ , in the presence of an external harmonic oscillator potential, is found from using eq. 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(cambridge university press, cambridge, ). hughes, eichten, and davies phys. rev. d , ( ) - https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /sym https://doi.org/ . /j.physletb. . . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . https://doi.org/ . /s - ( ) - https://doi.org/ . /s - ( ) - 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/physrevd. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevlett. . https://doi.org/ . /physrevd. . https://doi.org/ . /physrevd. . j h e p ( ) published for sissa by springer received: january , revised: march , accepted: march , published: march , su( )f analysis for beauty baryon decays avital dery, mitrajyoti ghosh, yuval grossman and stefan schacht department of physics, lepp, cornell university, ithaca, ny , u.s.a. e-mail: avital.dery@cornell.edu, mg @cornell.edu, yg @cornell.edu, ss @cornell.edu abstract: we perform a general su( )f analysis of b → cc̄s(d) decays of members of the beauty baryon antitriplet to a member of the light baryon octet and a singlet. under several reasonable assumptions we found ∣∣a(Ξ b → Λs)/a(Ξ b → Ξ s)∣∣ ≈ /√ |v ∗cbvcd/(v ∗cbvcs)| and ∣∣a(Λb → Σ s)/a(Λb → Λs)∣∣ ∼ . . these two relations have been recently probed by lhcb for the case of s = j/ψ. the former agrees with the measurement, while for the latter our prediction lies close to the upper bound set by lhcb. keywords: heavy quark physics, cp violation arxiv eprint: . open access, c© the authors. article funded by scoap . https://doi.org/ . /jhep ( ) mailto:avital.dery@cornell.edu mailto:mg @cornell.edu mailto:yg @cornell.edu mailto:ss @cornell.edu https://arxiv.org/abs/ . https://doi.org/ . /jhep ( ) j h e p ( ) contents introduction su( )f analysis . general su( )f decomposition . assumptions on ckm hierarchy and rescattering . isospin and u-spin decompositions . cp asymmetry sum rules . su( )f breaking Σ –Λ mixing in Λb decays . general considerations . anatomy of Σ –Λ mixing . the dynamic contribution . prediction for b(Λb → Σ j/ψ) comparison with recent data conclusions introduction a tremendous amount of b-baryons is produced at the lhc [ ]. this allows for angular analyses of Λb decays at lhcb [ ] and atlas [ ] and has led to evidence of cp violation in Λb decays [ ]. it is now feasible to scrutinize rare or suppressed b-baryon decays: recent results include the first observation of Λb → Λγ [ ] and the analysis of the isospin suppressed Λb → Σ j/ψ decay and the cabibbo-suppressed decay Ξ b → Λj/ψ [ ]. these increasingly precise measurements of baryon decays motivate us to perform an su( )f analysis of b → cc̄q (with q = s,d) decays of the heavy b-baryon to the light baryon and an su( )f singlet, b → b ⊗ . from the perspective of su( )f it makes no difference if the singlet, which we denote as s, is a j/ψ or any final state particle that does not carry any su( )f flavor, for example, a photon or a lepton pair. we start our analysis using two separate assumptions: ( ) we work in the su( )f limit and ( ) we treat the Λ and Σ as isospin eigenstates. we emphasize that these assumptions are not connected to each other. we later relax these assumptions and take into account corrections to the su( )f limit as well as deviations of the mass eigenstates of Λ and Σ from their isospin eigenstates. at leading order the decays b → b⊗ are mediated by tree-level b → cc̄q transitions. these correspond to a operator. in full generality however, we have to take into account – – j h e p ( ) additional contributions from loops that generate effective b → tt̄q and b → uūq transitions. the contribution from b → tt̄q can be neglected as it is a penguin and therefore suppressed and it gives only another under su( )f . in contrast, the up quarks in b → uūq can induce intermediate on-shell states leading to nontrivial effects from rescattering. specifically, the b → uūq transition has a more complicated isospin and su( )f structure and induces the higher su( )f representations and . therefore, as higher su( )f representations stem from rescattering, in the literature it is often assumed that these are suppressed. our strategy is to start with a very general model-independent viewpoint and then introduce additional assumptions step by step. while we mainly concentrate in this paper on the case where s = j/ψ, the general nature of our results make it possible to apply them also to radiative and semileptonic decays. ckm-leading su( )f limit clebsch-gordan coefficients for b → b ⊗ in b → s transitions have been presented in refs. [ – ]. in refs. [ , – ] hadronic models based on qcd factorization have been utilized, and in refs. [ , ] a covariant confined quark model has been applied. an su( )f analysis of b-baryon antitriplet decays to the light baryon octet and the η singlet can be found in ref. [ ]. further applications of su( )f to b baryon decays can be found in refs. [ – ]. works on b baryon decays beyond their su( )f treatment are given in refs. [ – ]. applications of su( )f methods on non-b baryon decays can be found in refs. [ – ]. further literature on baryon decays is given in refs. [ – ]. discussions of baryonic form factors can be found in refs. [ – ]. we present our su( )f analysis including isospin and su( )f breaking in section . after that we estimate in section the effect of Σ –Λ mixing in Λb decays, which is in general scale- and process-dependent, i.e. non-universal. we compare with recent experimental results in section and conclude in section . su( )f analysis . general su( )f decomposition the b → cc̄q (with q = s,d) decays of Λb, Ξ−b and Ξ b, which form the heavy baryon ̄, into a singlet s (e.g. s = j/ψ, γ, l+l−, . . . ) and a member of the light baryon , share a common set of reduced su( )f matrix elements after the application of the wigner-eckart theorem. these decays are specifically: • b → scc̄ transitions: Λb → Λs , Λb → Σ s , Ξ b → Ξ s , Ξ−b → Ξ −s . ( . ) • b → dcc̄ transitions: Ξ b → Λs , Ξ b → Σ s , Λb → ns , Ξ−b → Σ −s . ( . ) note that there are two additional allowed decays Λb → Ξ j/ψ and Ξ b → nj/ψ which are however highly suppressed by two insertions of weak effective operators, so we do not – – j h e p ( ) particle quark content su( )f state isospin u-spin hadron mass [mev] u u | 〉 , , ∣∣ , 〉 i | , 〉u n/a d d | 〉 ,− , ∣∣ ,− 〉 i ∣∣ , 〉 u n/a s s | 〉 , ,− | , 〉i ∣∣ ,− 〉 u n/a |Λb〉 udb | ̄〉 , , | , 〉i ∣∣ , 〉 u . ± . ∣∣Ξ−b 〉 dsb | ̄〉 ,− ,− ∣∣ ,− 〉 i | , 〉u . ± . ∣∣Ξ b〉 usb | ̄〉 , ,− ∣∣ , 〉 i ∣∣ ,− 〉 u . ± . |Λ〉 uds | 〉 , , | , 〉i √ | , 〉u− | , 〉u . ± . ∣∣Σ 〉 uds | 〉 , , | , 〉i | , 〉u + √ | , 〉u . ± . |Σ−〉 dds | 〉 ,− , | ,− 〉i ∣∣ , 〉 u . ± . |Σ+〉 uus | 〉 , , | , 〉i ∣∣ ,− 〉 u . ± . ∣∣Ξ 〉 uss | 〉 , ,− ∣∣ , 〉 i | ,− 〉u . ± . |Ξ−〉 dss | 〉 ,− ,− ∣∣ ,− 〉 i ∣∣ ,− 〉 u . ± . |n〉 udd | 〉 ,− , ∣∣ ,− 〉 i | , 〉u . ± . |p〉 uud | 〉 , , ∣∣ , 〉 i ∣∣ , 〉 u . ± . |j/ψ〉 cc̄ | 〉 , , | , 〉i | , 〉u . ± . table . su( )f , isospin and u-spin wave functions [ , , – ] and masses [ ]. for the indices of the su( )f states we use the convention |µ〉i,i ,y . the lifetimes of the mem- bers of the heavy baryon triplet are τΛb/τb = . ± . , where τb = ( ± )× − s, τΞ b = ( . ± . )× − s, τΞ− b = ( . ± . )· − s, [ ]. note that the exact form of the Σ –Λ mixing is phase convention dependent [ ]. our convention agrees with refs. [ , ]. another convention can be found e.g. in ref. [ ] in the form of |Λ〉= √ | , 〉u− | , 〉u and∣∣Σ 〉 =− | , 〉u− √ | , 〉u . consider them in our study here. the su( )f quantum numbers and masses are given in table . in this section we discuss the su( )f limit, su( )f -breaking effects are treated in section . . we can write the su( )f structure of the relevant b → s and b → d hamiltonians as [ ] hb→s = λcs(c̄b)(s̄c)+λus(ūb)(s̄u)+λts(t̄b)(s̄t) = λcs ( ) c , ,− +λus ( ( ) u , ,− +( ̄) u , ,− + √ ( ) u , ,− + √ ( ) u , ,− ) , ( . ) hb→d = λcd(c̄b)(d̄c)+λud(ūb)(d̄u)+λtd(t̄b)(d̄t) = λcd ( ) c ,− , +λud ( ( ) u ,− , − ( )u ,− , + √ ( ) u ,− , +( ) u ,− , ) . ( . ) see also refs. [ ] and [ ] for the application of these hamiltonians to b → j/ψk and b → dd, respectively. the notation for the subindices are such that (n)i,i ,y refers to – – j h e p ( ) the irreducible representation n of su( )f using the quantum numbers of strong isospin i, i and strong hypercharge y . in the standard basis of the gell-mann matrices i and y correspond to the eigenvalues of λ and λ , respectively. we further use the notation λcs ≡ v ∗cbvcs ∼ λ , λus ≡ v ∗ubvus ∼ λ , λts ≡ v ∗tbvts ∼ λ , ( . ) λcd ≡ v ∗cbvcd ∼ λ , λud ≡ v ∗ubvud ∼ λ , λtd ≡ v ∗tbvtd ∼ λ , ( . ) for the ckm matrix element combinations, where we indicate the hierarchies using the wolfenstein parameter λ. note that in eqs. ( . ) and ( . ) it is understood that su( )f operators in front of different ckm matrix elements have to be differentiated as they stem from different underlying operators. for instance, even if the two triplets generate linearly dependent clebsch-gordan coefficients, the respective matrix elements themselves are independent. they can, for example, have a relative strong phase. we write the reduced su( )f limit matrix elements as a k q , where k is the respective su( )f representation in the hamiltonian and q denotes the operator it stems from. the initial state is always a ∣∣ 〉 and the final state is always a | 〉, so that we are left with four reduced matrix elements in the su( )f limit: a c , a u , a u , a u . ( . ) the su( )f limit decomposition is given in table . the ckm-leading part of the b → s transitions agrees with refs. [ – ]. the clebsch-gordan coefficients are obtained using refs. [ – ]. the normalization of the amplitudes is such that b(b → b s) = |a(b → b s)| ×p(b ,b ,s) , ( . ) with the two-body decay phase space factors p(b ,b ,s) ≡ τb πm b √ (m b − (mb −ms) )(m b − (mb + ms) ) . ( . ) note that in cases where the su( )f singlet s is a multibody state, e.g. s = l +l−, we imply the appropriate phase space integration in eq. ( . ). note further, that we still work in the su( )f limit of the decay amplitudes. eq. ( . ) only accounts for the trivial su( )f breaking from phase space effects. additional su( )f breaking contributions are discussed in section . . therein, we estimate su( )f breaking effects to be of order %. note that the amplitudes in eq. ( . ) have a mass dimension, but we always care about ratios, so we can think about them as dimensionless quantities. note that phase space effects are of order % and thus they are well within the errors and could or could not be taken into account. for a model-dependent way to estimate these effects one can, for example, employ form factor results in refs. [ , ]. the reduced su( )f matrix elements can in principle be matched on a color suppressed tree diagram c, an exchange diagram e and penguin diagrams pq with quark q running in the loop. as examples we show the topological diagrams for Λb → Λj/ψ and Λb → Σ j/ψ in figure . in the following, however, we only perform the group theory treatment. – – j h e p ( ) decay ampl. a a c a u a u a u b → s a(Λb → Λs) √ λcs √ λus √ λus a(Λb → Σ s) − √ λus √ λus a(Ξ b → Ξ s) λcs λus √ λus √ λus a(Ξ−b → Ξ −s) λcs λus − √ λus − √ λus b → d a(Ξ b → Λs) − √ λcd − √ λud − √ λud √ λud a(Ξ b → Σ s) √ λcd √ λud − √ λud √ λud a(Λb → ns) λcd λud √ λud √ λud a(Ξ−b → Σ −s) λcd λud − √ λud − √ λud table . su( )f -limit decomposition. j/ψ b u d s u d c c̄ Λb Λ (a) c j/ψ b u d s u d c c̄ Λb Λ,Σ (b) e j/ψ b u d s u d c c̄ Λb Λ u, c, t (c) pq figure . topological diagrams for the decays Λb → Λj/ψ and Λb → Σj/ψ. note that in the exchange diagram one gluon alone can not create the j/ψ because it is a color singlet. – – j h e p ( ) the combined matrix of clebsch-gordan coefficients of b → s and b → d decays in table has matrix rank four, i.e., there are four sum rules, which read − √ a(Λb→Λs)+ √ a(Λb→Σ s)+a(Ξ b →Ξ s) = , (su( )f sum rule) ( . )√ a(Ξ b →Λs)− √ a(Ξ b →Σ s)+a(Λb→ns) = , (su( )f sum rule) ( . ) − √ a(Λb→Σ s) λud λus + √ a(Ξ b →Λs)+a(Λb→ns) = , (su( )f sum rule) ( . )√ a(Λb→Λs) λud λus − √ a(Λb→Σ s) λud λus −a(Ξ−b →Ξ −s) λud λus + √ a(Ξ b →Λs)+a(Ξ − b →Σ −s) = , (su( )f sum rule) ( . ) all of which are su( )f sum rules, and there is no isospin sum rule. note that there are two sum rules which mix b → s and b → d decays and two which do not. these sum rules are valid in the su( )f limit irrespective of the power counting of the ckm matrix elements, assumptions on the reduced matrix elements, or the particular su( )f singlet s, i.e. they are completely generic. . assumptions on ckm hierarchy and rescattering we now make some assumptions, which are not completely generic, i.e. their validity can for example depend on the particular considered su( )f singlet s, e.g. if s = j/ψ or s = γ. we first neglect the ckm-suppressed amplitude in b → s decays, that is we set λus/λcs → . in the isospin and su( )f limit for b → s decays we have then only one contributing reduced matrix element: a(Λb → Σ s) = , (isospin sum rule) ( . ) a(Ξ b → Ξ s) = a(Ξ−b → Ξ −s) , (isospin sum rule) ( . ) a(Ξ b → Ξ s) = √ a(Λb → Λs) . (su( )f sum rule) ( . ) we now move to make another assumption and that is to also neglect the λud terms for the b → d transitions. despite the formal power counting eq. ( . ), that is |λud| ' |λcd|, numerically we actually have [ ] ∣∣∣∣λudλcd ∣∣∣∣ ≈ . . ( . ) moreover, it is plausible that a u and a u are suppressed because they result from light quarks stemming from b → uūs(d) which induce intermediate on-shell states that rescatter into cc̄, see also refs. [ – ]. under the assumption that these terms are more or equally suppressed as su( )f -breaking effects we have many more relations. all seven non-zero decays we considered in table are then simply related by the clebsch-gordan coefficients – – j h e p ( ) in the first column. in addition to the sum rules eqs. ( . )–( . ), we have then √ a(Ξ b → Σ s) = a(Ξ−b → Σ −s) , (isospin sum rule) ( . ) a(Ξ b → Ξ s) = − √ a(Ξ b → Λs) λcs λcd , (su( )f sum rule) ( . ) − √ a(Ξ b → Λs) = √ a(Ξ b → Σ s) , (su( )f sum rule) ( . )√ a(Ξ b → Σ s) = a(Λb → ns) , (su( )f sum rule) ( . ) a(Λb → ns) = a(Ξ−b → Σ −s) . (su( )f sum rule) ( . ) . isospin and u-spin decompositions for comprehensiveness, we give also the isospin and u-spin decompositions of the hamil- tonians, which read hb→s = λcs( , )ci + λus (( , ) u i + ( , ) u i ) ( . ) = λcs ( ,− )c u + λus ( ,− )u u , ( . ) and hb→d = λcd ( ,− )c i + λud (( ,− )u i + ( ,− )u i ) ( . ) = λcd ( , )c u + λud ( , )u u , ( . ) where we use the notation (i,j) q i ≡o ∆i=i ∆i =j , (i,j) q u ≡o ∆u=i ∆u =j , ( . ) where q denotes the quark content of the operator the representation stems from and we absorbed clebsch-gordan coefficients into operators. using the isospin and u-spin states in table , we obtain the isospin decompositions in tables and and the u-spin decomposition in table . we note that the su( )f decomposition includes more information than the isospin and u-spin tables each on their own. an example is the ratio∣∣∣∣ a(Ξ b → Λs)a(Ξ b → Ξ s) ∣∣∣∣ = √ ∣∣∣∣∣〈 | ∣∣ 〉〈 ∣∣ ∣∣ 〉 ∣∣∣∣∣ ∣∣∣∣λcdλcs ∣∣∣∣ , ( . ) where the appearing reduced matrix elements are not related, e.g. the final states belong to different isospin representations. that means we really need su( )f to find the relation eq. ( . ). we can make this completely transparent by writing out the implications of eq. ( . ) for the corresponding u-spin decomposition. from table and eq. ( . ) it follows for the u-spin matrix elements − √ √ 〈 ∣∣∣∣ ∣∣∣∣ 〉c + √ 〈 ∣∣∣∣ ∣∣∣∣ 〉c = . ( . ) – – j h e p ( ) b → s decay ampl. a 〈 | | 〉c 〈 ∣∣ ∣∣ 〉c 〈 | | 〉u 〈 | | 〉u 〈 ∣∣ ∣∣ 〉u 〈 ∣∣ ∣∣ 〉u a(Λb → Λs) λcs λus a(Λb → Σ s) λus a(Ξ b → Ξ s) λcs − √ λus λus a(Ξ−b → Ξ −s) λcs √ λus λus table . isospin decomposition for b → s transitions. b → d decay ampl. a 〈 | ∣∣ 〉c 〈 | ∣∣ 〉u 〈 | ∣∣ 〉c 〈 | ∣∣ 〉u 〈 ∣∣ | 〉c 〈 ∣∣ | 〉u 〈 | ∣∣ 〉u a(Ξ b → Λs) − √ λcd − √ λud a(Ξ b → Σ s) √ λcd √ λud − √ λud a(Λb → ns) λcd λud a(Ξ−b → Σ −s) λcd λud λud table . isospin decomposition for b → d transitions. decay ampl. a 〈 | ∣∣ 〉c 〈 | ∣∣ 〉u 〈 | ∣∣ 〉c 〈 | ∣∣ 〉u 〈 ∣∣ | 〉c 〈 ∣∣ | 〉u b → s a(Λb → Λs) √ λcs √ λus √ √ λcs √ √ λus a(Λb → Σ s) − √ √ λcs − √ √ λus √ λcs √ λus a(Ξ b → Ξ s) λcs λus a(Ξ−b → Ξ −s) λcs λus b → d a(Ξ b → Λs) − √ λcd − √ λud √ √ λcd √ √ λud a(Ξ b → Σ s) √ √ λcd √ √ λud √ λcd √ λud a(Λb → ns) λcd λud a(Ξ−b → Σ −s) λcd λud table . u-spin decomposition. – – j h e p ( ) inserting this relation into the u-spin decomposition of the decay Ξ b → Λs in table , we obtain a(Ξ b → Λs) = √ λcd 〈 ∣∣∣∣ ∣∣∣∣ 〉c . ( . ) comparing this expression with the u-spin decomposition of the decay Ξ b → Ξ s in table , we arrive again at the sum rule eq. ( . ). in order that eq. ( . ) holds we need not only the suppression of other su( )f limit contributions as discussed above, but also the suppression of both isospin and u-spin vio- lating contributions. a non-vanishing dynamic isospin breaking contribution to Λb → Σ s would also be reflected in isospin and su( )f -breaking violations of eq. ( . ). we make this correlation explicit in section . . . cp asymmetry sum rules due to a general sum rule theorem given in ref. [ ] that relates direct cp asymmetries of decays connected by a complete interchange of d and s quarks [ – ], we can directly write down two u-spin limit sum rules: adircp (Ξ b → Ξ s) adircp (Λb → ns) = − τ(Ξ b) τ(Λb) b(Λb → ns) b(Ξ b → Ξ s) , ( . ) adircp (Ξ − b → Ξ −s) adircp (Ξ − b → Σ−s) = − b(Ξ−b → Σ −s) b(Ξ−b → Ξ−s) , ( . ) where the branching ratios imply cp averaging. note that the general u-spin rule lead- ing to eqs. ( . ) and ( . ) also applies to multi-body final states, as pointed out in refs. [ , , ]. it follows that eqs. ( . ) and ( . ) apply also when s is a multi-body state like s = l+l−. note that although the quark content of the Λ and Σ is uds, this does not mean that a complete interchange of d and s quarks gives the identity. the reason is given by the underlying quark wave functions [ ] |Λ〉∼ √ (ud−du) s, ∣∣Σ 〉 ∼ √ (ud + du) s, ( . ) where we do not write the spin wave function. eq. ( . ) shows explicitly that a complete interchange of d and s quarks in Λ or Σ does not result again in a Λ or Σ wave function, respectively. this is similar to the situation for η and η′, where no respective particles correspond to a complete interchange of d and s quarks [ ], see e.g. the quark wave functions given in ref. [ ]. we can put this into a different language, namely that in the u-spin basis the large mixing of | , 〉u and | , 〉u to the u-spin states of Λ and Σ , see table , destroys two sum rules which exist for the u-spin eigenstates. to be explicit, we define u-spin eigenstates which are not close to mass eigenstates |x〉 = | , 〉u , |y 〉 = | , 〉u . ( . ) – – j h e p ( ) decay ampl. a 〈 | ∣∣ 〉c 〈 | ∣∣ 〉u 〈 | ∣∣ 〉c 〈 | ∣∣ 〉u 〈 ∣∣ | 〉c 〈 ∣∣ | 〉u b → s a(Λb → xs) − √ λcs − √ λus a(Λb → y s) √ λcs √ λus b → d a(Ξ b → xs) √ λcd √ λud a(Ξ b → y s) √ λcd √ λud table . (unpractical) u-spin decomposition for the u-spin eigenstates |x〉 and |y 〉, see eq. ( . ) and discussion in the text. for these, we obtain the u-spin decomposition given in table . from that it is straight- forward to obtain another two cp asymmetry sum rules. these are however impractical, because there is no method available to prepare Λ and Σ as u-spin eigenstates, instead of approximate isospin eigenstates. consequently, we are left only with the two cp asymme- try sum rules eqs. ( . ) and ( . ). note that ckm-leading su( )f breaking by itself cannot contribute to cp violation, because it comes only with relative strong phases but not with the necessary relative weak phase. therefore, the individual cp asymmetries can be written as adircp = im λuq λcq im au ac , ( . ) where au,c have only a strong phase and to leading order in wolfenstein-λ we have [ ] im ( λus λcs ) ≈ λ η̄ ≈ . , im ( λud λcd ) ≈ η̄ ≈ . . ( . ) additional suppression from rescattering implies that on top of eq. ( . ) we have |au|� |ac|, i.e. the respective imaginary part is also expected to be small. this im- plies that we do not expect to see a nonvanishing cp asymmetry in these decays any time soon. the other way around, this prediction is also a test of our assumption that the λuq-amplitude is suppressed. . su( )f breaking we consider now isospin and su( )f breaking effects in the ckm-leading part of the b → s and b → d hamiltonians. this will become useful once we have measurements of several b-baryon decays that are precise enough to see deviations from the su( )f limit sum rules. su( )f breaking effects for charm and beauty decays have been discussed in the literature for a long time [ , , – ]. they are generated through the spurion  mu Λ − α md Λ + α ms Λ + α   = mu+md+ms Λ − ( md−mu Λ +α ) λ + √ ( mu+md− ms Λ −α ) λ , ( . ) – – j h e p ( ) with the unity and the gell-mann matrices λ and λ . the part of eq. ( . ) that is proportional to can be absorbed into the su( )f limit part. it follows that the isospin and su( )f -breaking tensor operator is given as δ ( ) , , + ε ( ) , , , ( . ) with δ = ( md −mu Λ + α ) , ε = √ ( mu + md − ms Λ −α ) , ( . ) where α is the electromagnetic coupling and we generically expect the size of isospin and su( )f breaking to be δ ∼ % and ε ∼ %, respectively. note that the scale-dependence of the quark masses, as well as the fact that we do not know how to define the scale Λ make it impossible to quote decisive values for δ and ε. eventually, they will have to be determined experimentally for each process of interest separately as they are not universal. for the tensor products of the perturbation with the ckm-leading su( )f limit op- erator it follows: ( ) , , ⊗ ( )c , ,− = √ ( ) , ,− + √ ( ) , ,− , ( . ) ( ) , , ⊗ ( )c , ,− = ( ) , ,− + √ ( ) , ,− , ( . ) ( ) , , ⊗ ( )c ,− , = √ ( ) ,− , − √ ( ) ,− , − √ ( ) ,− , + √ ( ) ,− , , ( . ) ( ) , , ⊗ ( )c ,− , = − ( ) ,− , − √ ( ) ,− , + ( ) ,− , , ( . ) so that we arrive at the su( )f breaking hamiltonians hb→sx ≡ λcs δ (√ ( ) , ,− + √ ( ) , ,− ) + λcs ε ( ( ) , ,− + √ ( ) , ,− ) , ( . ) hb→dx ≡ λcd δ (√ ( ) ,− , − √ ( ) ,− , − √ ( ) ,− , + √ ( ) ,− , ) + λcd ε ( − ( ) ,− , − √ ( ) ,− , + ( ) ,− , ) . ( . ) this gives rise to three additional matrix elements b , b , b . ( . ) – – j h e p ( ) decay ampl. a a c b b b b → s a(Λb → Λs)/λcs √ √ ε √ ε a(Λb → Σ s)/λcs √ δ − √ δ a(Ξ b → Ξ s)/λcs ε √ δ − √ ε √ δ a(Ξ−b → Ξ −s)/λcs ε − √ δ − √ ε − √ δ b → d a(Ξ b → Λs)/λcd − √ − √ δ + √ ε − √ δ + √ ε − δ − √ ε a(Ξ b → Σ s)/λcd √ √ δ − √ ε √ δ − √ ε − √ δ − ε a(Λb → ns)/λcd √ δ − ε − √ δ + √ ε √ δ + √ ε a(Ξ−b → Σ −s)/λcd √ δ − ε − √ δ − √ ε − √ δ − √ ε table . ckm-leading su( )f decomposition including isospin- and su( )f -breaking. the ckm-leading decomposition for b → s and b → d decays including isospin and su( )f breaking is given in table . the complete × matrix of the b → s matrix has rank four, i.e. there is no b → s sum rule to this order. as discussed in section after eq. ( . ) we see from table explicitly that isospin breaking contributions to a(Λb → Σ s) lead at the same time to a deviation of the ratio |a(Ξ b → Λs)|/|a(Ξ b → Ξ s)| from the result eq. ( . ). comparing to results present in the literature, in ref. [ ] two separate coefficient matrices of b → s and b → d decays are given in terms of the isoscalar coefficients, i.e. where the isospin quantum number is still kept in the corresponding reduced matrix element. we improve on that by giving instead the su( )f clebsch-gordan coefficient table that makes transparent the corresponding sum rules in a direct way and furthermore reveals directly the correlations between b → s and b → d decays. we also find the complete set of sum rules, and discuss how further assumptions lead to additional sum rules. we note that the first two sum rules in eq. ( ) in ref. [ ] are sum rules for coefficient matrix vectors but do not apply to the corresponding amplitudes because of the different ckm factors involved. Σ –Λ mixing in Λb decays . general considerations in this section we study the ratio r ≡ a(Λb → Σ physj/ψ) a(Λb → Λphysj/ψ) = 〈 j/ψΣ phys ∣∣∣h|Λb〉〈j/ψΛphys|h|Λb〉 . ( . ) – – j h e p ( ) in order to do this we need the matrix elements appearing in eq. ( . ). in the limit where isospin is a good symmetry and Σ phys is an isospin eigenstate, r vanishes, and therefore we are interested in the deviations from that limit. we study leading order effects in isospin breaking. we first note that we can neglect the deviation of Λb from its isospin limit. the reason is that regarding the mixing of heavy baryons, for example Σb–Λb, Ξ c–Ξ ′ c or Ξ + c –Ξ ′+ c , in the quark model one obtains a suppression of the mixing angle with the heavy quark mass [ – ]. it follows that for our purposes we can safely neglect the mixing between Λb and Σb as it is not only isospin suppressed but on top suppressed by the b quark mass. we now move to discuss the mixing of the light baryons. it has already been pointed out in ref. [ ], that a description with a single mixing angle captures only part of the effect. the reason is because isospin breaking contributions will affect not only the mixing between the states but also the decay amplitude. the non-universality is also reflected in the fact that the Λb → Σ transition amplitude vanishes in the heavy quark limit at large recoil, i.e. in the phase space when Σ carries away a large fraction of the energy [ ], see also ref. [ ] for the heavy quark limit of similar classes of decays. to leading order in isospin breaking we consider two effects, the mixing between Λ and Σ as well as the correction to the hamiltonian. we discuss these two effects below. starting with the wave function mixing angle θm, this is defined as the mixing angle between the isospin limit states ∣∣Σ 〉 = | , 〉i and |Λ〉 = | , 〉i, see eq. ( . ), into the physical states (see refs. [ – ]) |Λphys〉 = cos θm |Λ〉− sin θm ∣∣Σ 〉 , ( . )∣∣Σ phys〉 = sin θm |Λ〉 + cos θm ∣∣Σ 〉 . ( . ) the effect stems from the non-vanishing mass difference md − mu as well as different electromagnetic charges [ ] which lead to a hyperfine mixing between the isospin limit states. a similar mixing effect takes place for the light mesons in form of singlet octet mixing of π and η( ′) [ – ]. as for the hamiltonian, we write h = h + h where h is the isospin limit one and h is the leading order breaking. in general for decays into final states Λf and Σ f we can write〈 f Σ phys ∣∣h|Λb〉 = sin θm 〈f Λ|h|Λb〉 + cos θm 〈f Σ ∣∣h|Λb〉 ( . ) ≈ θm 〈f Λ|h |Λb〉 + 〈 f Σ ∣∣h |Λb〉 , 〈f Λphys|h|Λb〉 = cos θm 〈f Λ|h|Λb〉− sin θm 〈 f Σ ∣∣h|Λb〉 ≈ 〈f Λ|h |Λb〉 , where we use the isospin eigenstates |Λ〉 and ∣∣Σ 〉. it follows that we can write r ≈ θf ≡ θm + θ dyn f , θ dyn f ≡ 〈 f Σ ∣∣h |Λb〉〈f Λ|h |Λb〉 . ( . ) we learn that the angle θf has contributions from two sources: a universal part θm from wave function overlap, which we call “static” mixing, and a non-universal contribution – – j h e p ( ) θ dyn f that we call “dynamic” mixing. we can think of θf as a decay dependent “effective” mixing angle relevant for the decay Λb → Σ f. it follows b(Λb → Σ j/ψ) b(Λb → Λj/ψ) = p(Λb, Σ ,j/ψ) p(Λb, Λ,j/ψ) ×|θf| . ( . ) our aim in the next section is to find θf . . anatomy of Σ –Λ mixing we start with θm. because of isospin and su( )f breaking effects, the physical states |Λphys〉 and ∣∣∣Σ phys〉 deviate from their decomposition into their su( )f eigenstates both in the u-spin and in the isospin basis. as isospin is the better symmetry, we expect generically the scaling θm ∼ δ ε . ( . ) this scaling can be seen explicitly in some of the estimates of the effect. in the quark model, the qcd part of the isospin breaking corrections comes from the strong hyperfine interaction generated by the chromomagnetic spin-spin interaction as [ ] θm = √ md −mu ms − (mu + md)/ , ( . ) see also refs. [ , – ], and where constituent quark masses are used. eq. ( . ) agrees with our generic estimate from group-theory considerations, eq. ( . ). the same analytic result, eq. ( . ), is also obtained in chiral perturbation theory [ , ]. within the quark model, the mixing angle can also be related to baryon masses via [ , , ] tan θm = (mΣ −mΣ+ ) − (mn −mp)√ (mΣ −mΛ) , ( . ) or equally [ , , ] tan θm = (mΞ− −mΞ ) − (mΞ∗− −mΞ∗ ) √ (mΣ −mΛ) . ( . ) in ref. [ ] eqs. ( . )–( . ) have been derived within the generic “independent quark model” [ , ]. furthermore, ref. [ ] provides su( )-breaking corrections to eq. ( . ) within this model. note that eqs. ( . ) and ( . ) automatically include also qed cor- rections through the measured baryon masses. recently, lattice calculations of θm have become available that include qcd and qed effects [ ], and which we consider as the most reliable and robust of the quoted results. the various results for the mixing angle from the literature are summarized in table . it turns out that the quark-model predictions agree quite well with modern lattice qcd calculations. note however, that the lattice result of ref. [ ] (see table ) demonstrates that the qed correction is large, contrary to the quark model expectation in ref. [ ], and amounts to about % of the total result [ ]. – – j h e p ( ) method mixing angle θm [ ◦] ref. quark model: relation to baryon masses . ± . [ , ] quark model: hyperfine splitting + em interactions ' . [ ] lattice qcd+qed a . ± . [ ] lattice qcd+qed b . ± . [ ] lattice qcd without qed . ± . [ ] table . results for the Σ –Λ mixing angle. note that we adjusted the sign conventions for the results to match always the one of ref. [ ], see also the corresponding comment in ref. [ ]. for older lattice results for the “qcd only” scenario see refs. [ , ]. note that with alternate quark mass input taken from ref. [ ] the result for the “lattice qcd without qed” scenario is changed to θm = . ± . [ ]. in the literature the mixing angle has often been assumed to be universal and employed straight forward for the prediction of decays, see refs. [ , , , ]. it was already pointed out in refs. [ , ] that the Σ –Λ mixing angle can also be extracted from semileptonic Σ− → Λl−ν decays. the angle has also been directly related to the π–η mixing angle [ , ]. the ratio on the right hand side of eq. ( . ) can be extracted from η → π decays [ ] or from the comparison of k+ → π e+νe and k l → π −e+νe [ ]. for pseudoscalar mesons it has been shown [ , ] that the reduction of isospin violation from (md − mu)/(md + mu) to the ratio in eq. ( . ) is related to the adler-bell-jackiw anomaly [ , ] of qcd. note that in principle also θm is scale dependent [ ], as was observed for the similar case of π –η mixing in ref. [ ]. furthermore, θm has an electromagnetic component. depending on the relevant scale of the process in principle the qed correction can be large. we see from the lattice results in table that this is the case for θm. very generally, at high energy scales electromagnetic interactions will dominate over qcd ones [ ]. . the dynamic contribution the dynamical contributions to isospin breaking can be parametrized as part of the isospin- and su( )f -breaking expansion, see section . . explicitly we found θ dyn j/ψ ≡ 〈 j/ψ Σ ∣∣h |Λb〉〈j/ψ Λ|h |Λb〉 = δ × [√ b a c − √ b ̄ a c ] . ( . ) we expect that b ∼ b ̄ ∼ a c. the important result is that these effects are order δ. taking everything into account, very schematically we expect therefore the power counting θf ∼ ( δ ε ) m + δf ∼ θm [ + o(εf )] , ( . ) where δf and εf refer to isospin and su( ) breaking parameters that depend on f. – – j h e p ( ) . prediction for b(Λb → Σ j/ψ) we see from the power counting in eq. ( . ) that the static component θm dominates, as it is relatively enhanced by the inverse of the size of su( )f breaking. employing this assumption we obtain for θf ∼ θm ∼ ◦ ( . ) the prediction ∣∣∣∣a(Λb → Σ j/ψ)a(Λb → Λj/ψ) ∣∣∣∣ = |θf| ∼ . . ( . ) a confirmation of our prediction would imply the approximate universality of the Σ –Λ mixing angle in b-baryon decays. in that case we would expect that likewise∣∣∣∣a(Λb → Σ j/ψ)a(Λb → Λj/ψ) ∣∣∣∣ = ∣∣∣∣a(Λb → Σ γ)a(Λb → Λγ) ∣∣∣∣ = ∣∣∣∣a(Λb → Σ l+l−)a(Λb → Λl+l−) ∣∣∣∣ = ∣∣∣∣ a(Σ b → Λj/ψ)a(Σ b → Σ j/ψ) ∣∣∣∣ ∼ . , ( . ) up to su( )f breaking. note that Λb and Σb are not in the same su( )f multiplet, so that there is no relation between their reduced matrix elements. the above predictions are based on the assumption that the dynamic contribution is smaller by a factor of the order of the su( ) breaking. in practice, these effects may be large enough to be probed experimentally. thus, we can hope that precise measurements of these ratios will be able to test these assumptions. comparison with recent data we move to compare the general results of sections and to the recent lhcb data for the case s = j/ψ [ ]. particularly relevant to the experimental findings is the sum rule eq. ( . ) which we rephrase as∣∣∣∣ a(Ξ b → Λj/ψ)a(Ξ b → Ξ j/ψ) ∣∣∣∣ = √ ( + o(ε)) ∣∣∣∣λcdλcs ∣∣∣∣ ≈ . ∣∣∣∣λcdλcs ∣∣∣∣ , ( . ) where in the last step we only wrote the central value. the error is expected to be roughly of order ε ∼ %. the estimate in eq. ( . ) agrees very well with the recent measurement [ ]∣∣∣∣ a(Ξ b → Λj/ψ)a(Ξ b → Ξ j/ψ) ∣∣∣∣ = ( . ± . ± . ) ∣∣∣∣λcdλcs ∣∣∣∣ . ( . ) this suggests that the assumptions made in section are justified. however, from the su( )f -breaking contributions which we calculated in section . , we expect generically an order % correction to eq. ( . ). the measurement eq. ( . ) is not yet precise enough to probe and learn about the size of these corrections. however, su( )f breaking seems also not to be enhanced beyond the generic %. – – j h e p ( ) the only other theory result for the ratio eq. ( . ) that we are aware of in the literature can be obtained from the branching ratios provided in ref. [ ], where a covariant confined quark model has been employed. from the branching ratios given therein we extract the central value ∣∣∣∣ a(Ξ b → Λj/ψ)a(Ξ b → Ξ j/ψ) ∣∣∣∣ ∼ . λcdλcs , ( . ) where an error of ∼ % is quoted in ref. [ ] for the branching ratios. this estimate is also in agreement with the data, eq. ( . ) (see for details in ref. [ ]). finally, our prediction eq. ( . )∣∣∣∣a(Λb → Σ j/ψ)a(Λb → Λj/ψ) ∣∣∣∣ = |θf| ∼ . , ( . ) is only about a factor two below the bound provided in ref. [ ],∣∣∣∣a(Λb → Σ j/ψ)a(Λb → Λj/ψ) ∣∣∣∣ < / . = . at % cl. ( . ) a deviation from eq. ( . ) would indicate the observation of a non-universal contribution to the effective mixing angle, i.e. an enhancement of isospin violation in the dynamical contribution θ dyn j/Ψ . it seems that a first observation of isospin violation in Λb decays is feasible for lhcb in the near future. conclusions we perform a comprehensive su( )f analysis of two-body b → cc̄s(d) decays of the b- baryon antitriplet to baryons of the light octet and an su( )f singlet, including a discussion of isospin and su( )f breaking effects as well as Σ –Λ mixing. our formalism allows us to interpret recent results for the case s = j/ψ by lhcb, which do not yet show signs of isospin violation or su( )f breaking. we point out several sum rules which can be tested in the future and give a prediction for the ratios |a(Λb → Σ j/ψ)|/|a(Λb → Λj/ψ)| ∼ . and ∣∣a(Ξ b → Λj/ψ)/a(Ξ b → Ξ j/ψ)∣∣ ≈ /√ |v ∗cbvcd/(v ∗cbvcs)|. more measurements are needed in order to probe isospin and su( )f breaking corrections to these and many more relations that we laid out in this work. acknowledgments we thank sheldon stone for discussions. the work of yg is supported in part by the nsf grant phy . ss is supported by a dfg forschungsstipendium under contract no. scha / - . open access. this article is distributed under the terms of the creative commons attribution license (cc-by . ), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited. – – https://creativecommons.org/licenses/by/ . / j h e p ( ) references [ ] a. cerri et al., report from working group , cern yellow rep. monogr. 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[ ] c.q. geng, y.k. hsiao, c.-w. liu and t.-h. tsai, su( ) symmetry breaking in charmed baryon decays, eur. phys. j. c ( ) [arxiv: . ] [inspire]. [ ] c.q. geng, y.k. hsiao, c.-w. liu and t.-h. tsai, antitriplet charmed baryon decays with su( ) flavor symmetry, phys. rev. d ( ) [arxiv: . ] [inspire]. [ ] c.q. geng, y.k. hsiao, c.-w. liu and t.-h. tsai, charmed baryon weak decays with su( ) flavor symmetry, jhep ( ) [arxiv: . ] [inspire]. 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[ ] j. brod, y. grossman, a.l. kagan and j. zupan, a consistent picture for large penguins in d → π+π−,k+k−, jhep ( ) [arxiv: . ] [inspire]. [ ] y. grossman, a.l. kagan and j. zupan, testing for new physics in singly cabibbo suppressed d decays, phys. rev. d ( ) [arxiv: . ] [inspire]. [ ] y. grossman, a.l. kagan and y. nir, new physics and cp-violation in singly cabibbo suppressed d decays, phys. rev. d ( ) [hep-ph/ ] [inspire]. [ ] a.f. falk, y. grossman, z. ligeti and a.a. petrov, su( ) breaking and d -d̄ mixing, phys. rev. d ( ) [hep-ph/ ] [inspire]. [ ] m.j. savage, su( ) violations in the nonleptonic decay of charmed hadrons, phys. lett. b ( ) [inspire]. [ ] i. hinchliffe and t.a. kaeding, nonleptonic two-body decays of d mesons in broken su( ), phys. rev. d ( ) [hep-ph/ ] [inspire]. [ ] m. jung and t. mannel, general analysis of u-spin breaking in b decays, phys. rev. d ( ) [arxiv: . ] [inspire]. 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[…] read more posts navigation next categories debat informasi politik publik saran recent posts the medium game pc terbaru bergenre horor hilangkan rasa bosan dengan game gratis android tampilan debat perdana gibran dan bagyo bagaikan langit dan bumi terkait debat perdana pilkada solo biarkan warga yang menilai lokasi debat pilkada surabaya dipindahkan demi keamanan tags acara bersaing debat dukungan hal-hal harapan bangsa kandidat kegiatan kesimpulan live lokal maksimal masyarakat pandemi paslon pilkada politik publik team trending umum waktu warga wawancara portfolioline © heatherlench.com powered by themehunk wordpress theme genomic analysis of sleeping beauty transposon integration in human somatic cells giandomenico turchiano , maria carmela latella , andreas gogol-döring , , claudia cattoglio , fulvio mavilio , , zsuzsanna izsvák , zoltán ivics , alessandra recchia * center for regenerative medicine, department of life sciences, university of modena and reggio emilia, modena, italy, german centre for integrative biodiversity research (idiv) halle-jena-leipzig, leipzig, germany, institute of computer science, martin luther university halle-wittenberg, halle, germany, howard hughes medical institute, department of molecular and cell biology, university of california, berkeley, berkeley, california, united states of america, genethon, evry, france, max delbruck center for molecular medicine, berlin, germany, division of medical biotechnology, paul ehrlich institute, langen, germany abstract the sleeping beauty (sb) transposon is a non-viral integrating vector system with proven efficacy for gene transfer and functional genomics. however, integration efficiency is negatively affected by the length of the transposon. to optimize the sb transposon machinery, the inverted repeats and the transposase gene underwent several modifications, resulting in the generation of the hyperactive sb x transposase and of the high-capacity ‘‘sandwich’’ (sa) transposon. in this study, we report a side-by-side comparison of the sa and the widely used t arrangement of transposon vectors carrying increasing dna cargoes, up to kb. clonal analysis of sa integrants in human epithelial cells and in immortalized keratinocytes demonstrates stability and integrity of the transposon independently from the cargo size and copy number-dependent expression of the cargo cassette. a genome-wide analysis of unambiguously mapped sa integrations in keratinocytes showed an almost random distribution, with an overrepresentation in repetitive elements (satellite, line and small rnas) compared to a library representing insertions of the first-generation transposon vector and to gammaretroviral and lentiviral libraries. the sa transposon/sb x integrating system therefore shows important features as a system for delivering large gene constructs for gene therapy applications. citation: turchiano g, latella mc, gogol-döring a, cattoglio c, mavilio f, et al. ( ) genomic analysis of sleeping beauty transposon integration in human somatic cells. plos one ( ): e . doi: . /journal.pone. editor: sebastian d. fugmann, chang gung university, taiwan received july , ; accepted october , ; published november , copyright: � turchiano et al. this is an open-access article distributed under the terms of the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. data availability: the authors confirm that all data underlying the findings are fully available without restriction. the raw sequences data are uploaded in genbank database with the accession number srp . funding: funding was received for this study from italian ministry of university and research-firb (ar), debra international (ar) and the european research council (gt-skin) (fm). the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. competing interests: the authors have declared that no competing interests exist. * email: alessandra.recchia@unimore.it introduction the sleeping beauty (sb) transposon is a member of the tc / mariner transposon superfamily. tc /mariner elements are generally , – , bp in length and contain a single gene coding for the transposase that is flanked by terminal inverted repeats (ir). the irs of sb host a pair of binding sites containing short, – bp direct repeats (drs). both the outer and the inner pairs of transposase-binding sites are required for transposition. the sb transposase binds the irs in a sequence-specific manner, and mediates precise cut-and-paste transposition in a wide variety of vertebrate cells including human cells [ – ]. for this reason, the sb-based integration system is a valuable tool for functional genomics in several model organisms and represents a promising vector for human gene therapy [ , ]. however, a major bottleneck of any transposon-based application is the low transposition efficiency. therefore, considerable effort was dedicated to improve the sb integration machinery by modifying its irs and system- atically mutating the transposase gene. in , cui et al. carefully explored the structure and functions of the irs. they modified the outer and inner dr sites of both irs and the spacer sequence between the drs generating a new version of transposon ir, called t , with fourfold increased transposition efficiency [ ]. however, the transpositional activity of this system (and that of the first-generation transposon [ ]) is negatively affected by the size of transposon, resulting in an exponential drop for every kb introduced between the two ir. in , zayed et al. constructed the ‘‘sandwich’’ (sa) version of the transposon vector [ ]. the sa ir consists of two complete transposon elements in a head to head orientation, flanking a dna expression cassette, thereby forming a sandwich-like arrangement. mutation of the terminal ca nucleotides of the right ir abolishes cleavage at the innermost transposon ends; therefore, only the four terminal drs represent the catalytic substrate for the ‘‘cut and paste’’ transposition. the sa transposon showed a . -fold enhanced activity over first generation transposon to integrate , . kb-dna sequence upon sb transposase delivery. five years later, a transposase -fold more active than sb , named sb x, was developed by a high- throughput, pcr-based dna shuffling strategy [ ]. the im- proved integration efficiency associated with sb transposition opened new avenues for its application. the hyperactive sb x transposase was employed to obtain highly efficient germline transgenesis in pigs [ , ] rabbits [ ] and rodents [ , ], stable plos one | www.plosone.org november | volume | issue | e http://creativecommons.org/licenses/by/ . / http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf transfer of therapeutic genes in clinical relevant cells [ , – ], and reprogramming of mouse embryonic and human foreskin fibroblasts into ips cells [ ]. in this study, we investigated the integration efficiency of large expression cassettes mediated by the optimized sb elements: the sa transposon and the sb x transposase. we report a side-by- side comparison between the sa and the t transposons carrying dna cargo of increasing length. we performed a deep molecular characterization of sa-mediated integrants in epithelial cell lines and in primary immortalized keratinocytes stressing the sb system with cargos up to kb. these data provide evidence for stability of sb-mediated integration and the reproducibility of the cut-and- paste mechanism even with large transposons embedded between two double irs. moreover, clonal analysis reveals a linear correlation between transposon copies harboured into the genomic dna and their expression, an important characteristic for gene therapy application. finally, high-resolution, genome-wide map- ping of sa integrations in human keratinocytes revealed a close-to- random integration pattern with respect to genes and chromo- somes, highlighting a relative low risk of genotoxicity as previously reported for sb transposition in cell lines [ – ]. interestingly, the high-throughput analysis of sa integration sites showed an overrepresentation of integration events into repetitive elements (re) of the human genome, in particular satellite, small rna and line elements. materials and methods cell culture hela cells were cultured using dmem medium (lonza) added with % fetal bovine serum (fbs), % l-glutamine (l-gln) and % penicillin-streptomycin (pen/strep). for each experi- ment, an aliquot of cryo-preserved hela cells was thawed and plated on cm dishes. upon reaching – % of confluency, cells were re-plated on -wells culture plates at a concentration of cells/well. after h, cultures in each well were at – % confluency, ready to be transfected. mouse nih t fibroblast cell line was maintained in dulbecco’s modified eagle’s medium (euroclone), supplemented with % bovine serum. we have used sv immortalized keratinocytes derived from a patient affected by generalized atrophic benign epidermolysis bullosa (gabeb) produced by borradori et al. [ ] and kindly provided by j.w. bauer. gabeb cells were cultivated in epilife medium supplemented with human keratinocyte growth supple- ment (hkgs) (invitrogen, us). epilife is a serum-free keratino- cyte culture medium with a low calcium ( . mm) concentration supplemented with hkgs which results in a final concentration of . % (v/v) bpe, lg/ml bovine insulin, . lg/ml hydrocorti- sone, lg/ml bovine transferrin and . ng/ml human egf. upon reaching – % of confluency, cells were re-plated on - wells culture plates at a concentration of . cells/well. after h, cultures in each well were at – % confluency, ready to be transfected. plasmid constructs the plasmid carrying the t irs including a venus reporter gene driven by the chicken b actin promoter fused to cmv early enhancer element (caggs) and the construct coding for the sb x were described in mates et al. [ ]; the sa transposon irs were described in zayed et al. [ ]. the caggs venus expression cassette was dra iii excised from pt . and introduced into ecorv digested psa to obtain psa . . pt . and pd [ ] were digested with xbai to clone a non coding dna of . kb from pd into the transposon. two fragments of the first intron of the hprt gene were pcr amplified and cloned into the pcr . (topo cloning kit, invitrogen) plasmid. the pt plasmid was cloned ligating the pt caggs venus spei with nhei fragment of the amplified hprt intron . the pt plasmid derives from pt digested with clai ligated to the noti fragment of the amplified hprt intron . finally, pt was obtained by ligating a third sequence amplified from the hprt intron with pt through ecori restricted ends. the psa . plasmid was digested with nhei and ligated to the nhei non coding fragment of the hprt gene to obtain the psa . . then the psa . was digested with pmei enzyme and ligated with a pvuii fragment of the hprt intron to obtain the psa . to enlarge the psa , a sequence amplified from the intron of the lamb gene was introduced by ecorv compatible ends to obtain psa . transfection-based transposition and calculation of transposition efficiency hela and gabeb cells were both transfected with fugenehd transfection reagent (roche). for each sample mg of dna were added to ml of either dmem (for hela) or epilife (for gabeb). the media used for this transfection reaction mix were not added with fbs, l-gln or pen/strep. the transposon/transposase amounts of plasmid dna were calculated to respect the stoichiometric ratio of : or, for transposon . kb, : , in a total quantity of mg. mg of transposon-only plasmid were used for non-transposed control. each transfection reaction mix was complexed with ml of fugenehd ( ml with sa and t in gabeb cells) and subsequently mixed by pulse-vortexing for a few seconds. the mixes were thereafter left at room temperature for in order to allow the formation of lipoplexes. after the had expired, each mix was added drop-by-drop to a cell culture sample, which was subsequently incubated at uc. hela cells were transfected with calcium phosphate method using mg of - or kb transposons mixed with the plasmid carrying the transposase expression cassette. the percentage of venus + cells was determined and – days post-transfection via flow cytometry and the transposition efficiency was calculated as: venus + cells at – days post transfection/venus + cells at day . cells that were only transfected with the transposon plasmid represented the control for background integration events. transposed clones were analysed via flow cytometry to determine the presence of doublets and the venus mean fluorescence intensity (mfi). isolation of single cell clones gabeb cells were limiting diluted to obtain a concentration of . cell/well, plated onto lethally irradiated nih t cells and cultured in keratinocyte growth medium, a dmem and ham’s f media mixture ( : ) containing fcs ( %), penicillin- streptomycin ( %), glutamine ( %), insulin ( mg/ml), adenine ( . mm), hydrocortisone ( . mg/ml), cholera toxin ( . nm), and triiodothyronine ( nm). after week, the medium was replaced by epilife medium supplemented with hkgs. after weeks gabeb cells were trypsinised at subconfluence and re- plated without the nih t feeder-layer in epilife hkgs medium. hela cells were seeded to obtain a concentration of . cells/ well in a well plate in dmem medium complemented with % fbs. sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e southern blot analysis ten mg of genomic dna, extracted from cells by a qiamp dna mini kit (qiagen), were digested overnight with nhei (sa . -derived clones) and aflii (t -derived clones) to verify the copy number of the transposed cassette, or with ncoi (sa . -derived clones) and mfei plus ndei (t -derived clones) to verify the integrity of the transposed cassette. digested gdna was run on a , % agarose gel, transferred to a nylon membrane (duralon, stratagene) by southern capillary transfer and probed with cpm p-labeled venus probe according to standard techniques [ ]. pcr screening for episomal sb vectors about ng of template gdna were used in a pcr reaction. primers capable to amplify the amp resistance gene or the sb x transposase (table s ) were used to detect genomic integrations of sa . backbone and sb x, respectively. pcr conditions were as follows: at uc, at uc and at uc for cycles. lm-pcr and bioinformatic analysis integration sites were amplified by linker mediated pcr (lm- pcr), as described [ ]. briefly, genomic dna was extracted from . transposed cells and digested with msei and xhoi enzyme to prevent amplification from internal mutated ir fragments. an msei double-stranded linker was then ligated and lm-pcr performed with nested primers specific for the linker and sa ir/dr (table s ). lm-pcr derived amplicons were run on a roche/ gs flx using titanium chemistries by gatc biotech ag next gen lab. a valid integration contained: the tagpsair nested primer and the entire sa ir/dr sequence up to a ta dinucleotide. alignment pipeline. , sequencing reads were tested for the presence of the sa ir sequence and ta dinucleotide. the sa ir and any primer sequences were trimmed, and the remaining reads starting with ta dinucleotides were mapped to the human genome (hg ) using ncbi blast (blastn with default param- eters). we kept only reads which were mapped to a single genomic site with at least % sequence identity and an e-value of at most . . only reads which could be mapped from their end onwards were considered for further analysis. redundant reads mapping to identical genomic positions were collapsed. this way we got unique sa integration sites. for the statistical analysis we generated , control sites in- silico taking into account the bias introduced by lm-pcr techniques. we first generated artificial reads starting with ta dinucleotide of the human genome in a way that the control sequences had both the length and the frequency of msei restriction sites (ttaa) as observed in real sequencing reads. the artificial reads were then processed by the same mapping criteria used for the sa sites. rm blast analysis. analyses of repetitive element were performed with repeatmasker blast (http://repeatmasker.org) [ ]. to achieve reliable and comparable results we processed the raw sequences trimming out the primer sequences used in lm- pcr, the ir/ltr/linker specific sequences following the primers. resulting reads were further trimmed till the th nucleotide discarding every sequence with less than nucleotides. finally, we collapsed the reads that were either identical or with one mismatch. a two-sample test for proportions was used for pairwise comparison of the re within the different datasets. for statistical analysis we created control sets as follows. we first randomly sampled million sequences bp in length from the human reference genome (hg ). then we discarded all sequences not starting with ta. the resulting set of , ta-weighted sequences was used as a background for tneo sb integrations. for a second random control set we first randomly sampled million sequences of length bp from the genome. then we discarded all sequences not starting with ta, or either not containing the msei restriction motif ttaa or having a ttaa within the first bp of the sequence. after removing the part of the sequences following the first occurrence of ttaa, we received , sequences of lengths between bp and bp, which were weighted for ta and msei and could be used as a background for sa integrations. we passed the generated sequences through the same filtering/trimming pipeline as the actual integration reads. a third random control set of , genomic sequences weighted for msei was adapted from cattoglio et al. [ ] and used as a background for mlv and hiv integrations. bidirectional pcr mapping on gabeb clones transposon integrations in gabeb clones were amplified by lm-pcr as described. pcr products were shotgun-cloned (topo ta cloning kit, invitrogen) and then sequenced. sequences between the ta and the linker primers were mapped onto the human genome by the blat genome browser (ucsc human genome hg ). sequences featuring a unique best hit with $ % identity to the human genome were considered genuine integration sites. to confirm the genuine integration in both directions we design primers on the genomic region hit and performed a direct pcr in conjunction with the psair specific primer for the sa ir sequence (table s ). the derived amplicons were loaded on agorose gel and checked for the expected length. results efficiency of t and sa transposons the sandwich (sa) transposon vector has superior ability to transpose . kb transgenes with respect to the first-generation transposon when sb transposase was provided [ ]. neverthe- less, the t transposon, resulting from site-specific mutations in the ir sequences and insertion of double ta flanking each ir, has been demonstrated to have a four-fold enhanced activity over the first-generation transposon construct [ ]. a side-by-side compar- ison of sa and t transposon was needed to address the transposition efficiency of increasing dna cargoes and to verify their molecular behaviours once integrated into the human genome. we generated sa- and t -based plasmids (sa . and t . figure ) keeping the venus reporter gene as standard expression cassette. increasing sizes of a non-coding human stuffer dna ( -, . - and . kb in the sa plasmid; . -, . - and . kb in the t plasmid) were introduced between the two ir/dr to produce transposons of comparable length. for the sake of simplicity, we named these plasmids with the transposon construct type and the size of the transposable cassette expressed in kilobases (figure ). transposition experiments were performed in hela cells and in immortalized primary keratinocytes derived from patients affected by generalized atrophic benign epidermolysis bullosa (gabeb), an inherited skin adhesion defect. all the experiments aimed at the identification of the integration efficiency of the ir-flanked transgene were measured by long-term venus fluorescence in the absence of selective pressure. we co-transfected the sb x transposase-expressing plasmid together with transposon plasmids in two different molar ratios ( : or : ) depending on the transposon length. larger cargos required more transposon dna to reach good transfection efficiency. sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e http://repeatmasker.org at least three independent experiments for each cell type and transposon were performed in order to reduce variability due to the transfection procedure. mock-transfected hela and gabeb cells, and cells transfected with the t or sa venus constructs alone were used as controls (in the absence of transposase, no transposition event should occur and residual reporter gene expression after long periods would only be attributable to noise or to rare random plasmid integration events). transgene expression all along the culture period (up to days) was measured via flow cytometry to follow the trend of the signal that persists in presence of sb x and drops without the transposase (figure s ). the transposition efficiency was normalized by transfection efficiency (numbers of cells that received the plasmids after transfection) and calculated as the ratios between the percentage of venus + cells at the endpoint ( – days) and the percentage of transfected cells – days after dna delivery to the cells. the endpoint of each experiment is achieved when the percentage of venus + cells in the sample transfected with the transposon alone stabilized to less than , . %. figure a and b show the transposition rate obtained in hela and gabeb cells. as previously reported [ , ], the transposition efficiency was inversely proportional to the transpo- son size. in hela cells, the transposition efficiency dropped . fold (from . % to . %) when increasing the cargo payload from . kb to kb, independently of the transposon structure (t or sa). interestingly, this size-dependent effect was less pronounced in gabeb cells. in this cell type the decrease was of . fold (from % to %) for t and sa and the transposition rate for kb transposons remained approximately % compared to the . % in hela cells. clonal molecular analysis although we performed a molecular characterization of almost all t and sa vectors in hela or gabeb cells (table s .), we focused our genomic analysis on a relatively large t and sa transposons cassette ( kb) and on gabeb keratinocytes. bulk populations of transposed cells were sorted for venus expression – days post transfection and cloned by limiting dilution. genomic dna extracted from each clone was first investigated by pcr for the presence of the transposon backbone and sb x expressing plasmid. notably, we scored . % of clones ( out of ) positive for the ampicillin sequence present within the transposon backbone about days post transfection, while few ( out ) of the analysed clones were positive for the sb x sequence (table s ). figure . transposon fleet. schematic representation of the generated plasmids. sb x carries the hyperactive sleeping beauty transposase coding sequence placed under the control of the cmv promoter and followed by an sv poly-adenylation (pa) signal. the transposons t and sa possess the expression cassette consisting of the caggs promoter, venus reporter gene and sv pa signal. the stuffer dna represented has variable increasing size. the arrows represent the ir/dr ends recognised by the transposase. sa constructs are characterized by the presence of two complete ir/dr at each ends (white and black arrows) and the asterisks underline the ir mutated site not recognized as a catalytic substrate by the transposase. numbers following t or sa abbreviation indicate the size in kilobases of the transposed cassette. doi: . /journal.pone. .g sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e we next performed southern blotting on the genomic dna of clones for each transposon type to determine the transgene copies harboured in the genome and their integrity. to this end, we digested the genomic dna with aflii (t clones) or nhei (sa clones) that release fragments longer than . and . kb. hybridization with a venus-specific probe showed that most of the sa treated samples ( out of ) carry a single integrated transposon, only clone (# ) had copies, and out of clones contained copies (# , # ) resulting in an average copy number of . . surprisingly, gabeb clones obtained with t , harbour to copies with an average of integrated transposons per clone (figure a). in general we observed that the mean copy number is more affected by the transfection efficiency (table s ) respect to the size and type of transposons. further restriction analysis performed with mfei and ndei on t clones and with ncoi on sa clones showed that all clones harbour the full-length transposon cassette (figure b). among the integrated transposons in the t clones, only one, belonging to clone # , is shorter than expected. none of the integrated transposons in the sa clones was rearranged. to unequivocally prove that all the integration events mediated by sa transposition resulted from a genuine ‘‘cut and paste’’ mechanism, we mapped the insertion site at both transposon ends using an adapted version of linker-mediated pcr (lm-pcr) [ ]. ten venus-expressing gabeb clones, derived from transposition of the sa . plasmid, were examined. six integrants (# , , , , , ) belonging to clones were bi-directionally mapped by lm-pcr. additional integrants were revealed by lm-pcr and confirmed by specific pcr on the genomic region flanking the opposite ir (figure c). importantly, almost all the integration events occurred without genomic rearrangements, deletions or insertions, in the target sites. only out of integrations (# and # belonging to clone ) could not bi- directionally confirmed. finally, we correlated the expression level of the reporter gene with the copy number of the transposon. the positional effect variegation primarily observed with retroviral and lentiviral vectors [ ] could lead to the silencing of the therapeutic gene delivered by the vector. we asked weather the sb integrations would be affected by this phenomenon. we correlated the expression of venus protein, measured by mean fluorescence intensity (m.f.i.), with copy number of either the sa and t transposon, as determined by southern blot or q-pcr analyses of gabeb clones. for comparison, we analysed the m.f.i of a gfp reporter gene, driven by the human keratin promoter, in hacat clones isolated upon lv transduction. a linear correlation curve was traced to retrieve the r coefficient of determination. transposon samples show an r = . with a statistically defined correlation between two variables (pn = . ). lv samples display an r = . with a null defined correlation (figure ). independent analysis of transposed clones obtained in different cells (hacat and gabeb) and carrying a reporter gene driven by pgk or caggs promoter showed comparable results indicating common directly correlation between mfi and copy number (data not shown). we conclude that sb integrants tend to express their cargo faithfully, and multi-copy integrants express in a copy-number dependent manner, consistent with earlier observations [ ]. integration pattern analysis in the last few years, several papers described the integration profile of the sb, piggybac (pb), and tol transposons [ – , – ]. here we report the integration profile and preference of the sandwich compared with the first-generation sb transposon [ ] in human epithelial cells. to generate a library of sa integration events, we transfected million gabeb cells with sa transposon- and sb x-carrying plasmids. the % of venus- positive cells were sorted three days after transfection to enrich the population expressing the reporter gene. a %-pure sorted population was kept in culture for weeks to dilute the un- integrated sa vector reaching a stable % venus + bulk population. we used lm-pcr and pyrosequencing to generate , non-redundant sa-linked genomic sequences in human immortalized gabeb keratinocytes. the blast alignment re- trieved , unambiguously mapped integration sites. as a control, , random unique sequences were generated in silico balancing the biases introduced by the lm-pcr (amplicon lenght and msei proximity) and the availability of the ta dinucleotides in the genome. in the analysis we also annotated a large dataset ( , hits) generated in hela cells transposed with the first- generation tneo transposon and selected for weeks with neomycin [ ]. the integration sites and control sites were annotated as transcriptional start site (tss)-proximal when mapping in the . kb window around a tss, intragenic when mapping within a transcription unit, and intergenic in all other cases. among sa integrations, . % were in an intergenic position, . % were within the transcribed portion of at least gene, and . % was within a kb window encompassing the tss figure . transposition efficiency. hela (a) and gabeb (b) cells were co-transfected with the t and sa transposons- and transposase- carrying plasmids. the transposition rate, on the y axis, is derived by the ratio between the percentage of venus + cells at about and days post transfection. data are representative of three independent experiments (mean sem; n = ). doi: . /journal.pone. .g sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e figure . molecular characterization of the sleeping beauty-mediated integration events in gabeb cell clones. (a) southern blot analysis of genomic dna from gabeb cell clones digested with nhei (sa clones) or aflii (t clones), single cutter in the transposon cassette, and hybridized to a venus probe. a single band higher than . kb (sa clones) and . kb (t clones) indicates integration of one copy of the transposon into the genome. multiple venus-specific bands correspond to repeated integration events. (b) southern blot analysis of genomic dna from (sa) and (t ) clones digested with ncoi (sa clones) or mfei and ndei (t clones). the expected venus-specific band corresponding to kb for sa and . kb for t transposon indicates the correct integration of the transposons into the genome. c, mock-transfected cells; red bars, venus-specific probe. clone showing rearrangement of the transposon cassette is highlighted by black asterisk. (c) bi-directional mapping of the junctions between transposon and genomic dna. the table summarizes integrations belonging to single clones. for each integrant, the underlined sequence sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e (figure a; the complete list of sequences is available in genbank database with the accession number srp ). in general, the distribution of the sb integrants in both datasets is fairly random and resembles the composition of the human genome showing no statistical differences compared to their relative controls, i.e. all p-values (both two-sample tests for proportions and fisher’s exact tests) were . . we then analysed the frequency of human repetitive elements in the transposon libraries, sa and tneo [ ], and their relative weighted controls availing of the rm blast browser [ ]. for comparison we also analysed two viral-derived integration datasets (mlv and hiv) generated in human cd + multipotent hematopoietic progenitor cells (hpcs) [ ] and their control library weighted for msei restriction site distribution. the raw data generated by deep sequencing of the lm-pcr (applied to sa, mlv and hiv treated cells) and lam-pcr (applied in [ ]) products were filtered and trimmed in order to rescue the genuine integration events (see materials and methods). after filtering and trimming we retrieved , and , unique sequences in sa and first-generation vector libraries, respectively, and , and , unique sequences from mlv and hiv datasets, respec- tively. we generated large control datasets taking into account the bias introduced by the respective technique. in particular from the hg genome database we retrieved , control reads weighted for msei, , sequences weighted for the presence of ta dinucleotide hit by the sb transposons, and , sequences msei- and ta-double weighted. the rm blast analysis revealed an overrepresentation of res in the sa integrations ( %) with respect to the ta and msei- weighted control ( %) and to all the other datasets analysed (figure b). in particular, satellite, small rna and line elements were enriched in the sa library ( -, . - and . -fold increase over the background, respectively) whereas in the first- generation vector library only a slight increase in the satellite and simple repeats elements was measurable ( . - and . -fold over the background, respectively); comparable line frequency was detected. besides the higher frequency in the satellite elements, the two sb transposon datasets share a slight under-representation of sine, ltr and dna transposable elements in comparison with their random control libraries. we introduced mlv and hiv libraries to compare the frequency of integration into re generated by a retroviral integrase-mediated integration mecha- nism. the rm blast analysis pointed out that viral vectors disfavour integration in re ( – % vs %), and, in particular, satellite, ltr and line elements are underrepresented. these data clearly confirm a difference in the integration site selection between viral vectors and sb transposons and identify new signatures in the sa integrome that should be taken into consideration when using them as tools for genetic manipulation. discussion the sb transposon irs were mutated to improve their capacity to be mobilized and, to date, there is not a direct comparison that define genetic characteristics of the t and sa irs [ ]. in this study, hela cells and gabeb keratinocytes [ ] were transfected with a panel of t or sa transposons carrying size-increasing venus expression cassette in combination with sb x plasmid (figure ). transfection rate was higher in hela than in gabeb cells (figure s ) and the transposition efficiency was inversely proportional to the transposon size (figure ). interestingly, hela cells were severely affected by the transposon size compared to primary immortalized cells. these results suggest that the transposase activity could be favoured by some cellular factor differentially expressed in gabeb and hela cells. nonetheless, t and sa constructs carrying cargos of comparable size showed similar transposition efficiency in both cell lines. from these data we can conclude that the t ir construct is interchangeable with the sa construct with some advantages: t has shorter irs thereby it could accept a larger cargo cassette. transposed gabeb and hela populations were subjected to limiting dilution to obtain a single cell derived expansion. the derived clones were employed to characterize several molecular parameters: transposon-independent insertion, copy number, genomic stability, faithful transposition activity, correlation between copy number and expression of the integrated cassette. the sb x sequence was retrieved in out of analysed clones while almost % of the clones ( clones) were found positive for the transposon backbone sequences (table s ). we hypothesize that the plasmid backbone carrying the transposon could have some advantages to remain episomal or to integrate in the genome. the transposon excision step from the plasmid leaves the backbone with a double strand break that induce recruitment of the endogenous repair machinery and integration into the cell genome. we also analysed the copy number of the clones. figure a shows an average of . sa copies/clone while t copy number spans from to transposons with an average of copies. this difference mostly depends on the transfection efficiency as confirmed by the analysis of the other transposed cell populations generated in this study. therefore, it is possible to fine tune this parameter by adjusting the ratios of the two sb represents a portion of the transposon irs, left (cagtt) and right (aactg) separated by dots; ta dinucleotide (in bold) is the target site correctly duplicated after transposition. hit chromosomes and positions are reported. unk, unknown region of the human genome based on ucsc hg assembly. doi: . /journal.pone. .g figure . correlation between copy number and expression of the integrated cassette. mean fluorescence intensity (m.f.i.) of gabeb clones positive for venus expressing sb transposons are represented as circles; triangles indicate the m.f.i. of gfp + hacat clones transduced with a lentiviral vector (lv). standard deviation bars are present for those clones carrying the same copy number. r coefficients of determination were extracted from the linear regression plot, green line for sa and t transposons and red line for lv. doi: . /journal.pone. .g sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e components used for transfection or, as previously reported, bypass the transfection procedure through the viral delivery of transposase and transposon by adenoviral vector [ ], integration defective lentiviral vector [ , ], retroviral particle [ ] and adeno-associated vectors [ ]. we were able to associate copy number of the transposon with the expression level of the venus fluorescence gene. mean fluorescence intensity does follow a direct proportion with the copies harboured (figure ). in contrast, expression of the reporter gene in lentiviral-mediated integrants does not correlate with copy number and is more subjected to the activity of surrounding genomic sequences [ , ]. next, the integrated transposons in these clones were also analysed for their integrity via southern blot. retroviral and lentiviral vectors can rearrange during the reverse transcription step resulting in partially-deleted integrated proviruses, a frequent occurrence in transgene hosting repetitive sequences [ , ]. the sb mediated integration, by contrast, does not require reverse transcription and thus is expected to preserve the integrity of the transgene. ninety-eight percent of the integrants, resulting from t and sa transposition, have a correct size (figure b). the sandwich transposon has a doubled ir/dr structure at both ends with transposase binding sites in total. in principle, every transposase unit, bound to one dr site, could interact with the others to create different chiasm geometries (also described in [ ]); some of these conformations could modify the integration activity resulting in chromosomal aberrations. to investigate the fidelity of the transposition process gabeb clones were mapped bi-directionally by lm-pcr and transposon-genome junction was amplified by site-specific pcr. twenty-five integra- tions, out of ( . %), were validated for a canonical transposition event with the ta target site duplication signature at both ends (figure c). two integrations mapped by lm-pcr were not confirmed in the opposite transposon end suggesting figure . integration pattern analysis. (a) integration sites were annotated as ‘‘tss-proximal’’ when occurring within a distance of . kb from the gene’s tss, as ‘‘intragenic’’ when occurring in a gene body and as ‘‘intergenic’’ in all other cases. black bars represent exons of a schematic gene, arrowhead indicates the direction of transcription. distribution of sa, tneo and random integration sites in the genome is plotted accordingly to defined annotations. (b) distribution of repetitive elements in sb sa and tneo libraries, in mlv and hiv libraries. relative weighted random libraries were reported: ta and msei-weighted for sa, ta-weighted for tneo and msei-weighted for mlv and hiv libraries. **p# , *p# . doi: . /journal.pone. .g sleeping beauty transposition in human cells plos one | www.plosone.org november | volume | issue | e rearrangements probably caused by the repair mechanism occurred in the transposition break. lm-pcr was also employed to derive a high-definition map of sa/sb x integration sites in the genome of a transposed gabeb bulk population. this analysis is commonly applied to integrating vectors (i.e. retroviral and lentiviral vectors) because it allows to evaluate genotoxicity [ , ] and to understand molecular mechanism driving the integration towards specific regions of the genome [ , – ]. the technique returned , sa unambiguously mappable integration sites randomly distrib- uted throughout the human genome, in accordance with previously published data on first-generation transposon [ , ] (figure a). for gene therapy purposes, the sb system results in a safer integration profile compared to other integrating vector such as tol , pb transposon and retroviral vectors [ – , , ], which favor tss-proximal regions or gene body sequences. although the integration site distribution in relation to genes was found close to random, the rm blast analysis shows a significant bias distribution of sa integrations in repetitive elements (re), particularly in satellite, line and small rna genes. it could be that these genomic regions are favourable for integration due to their base composition (ta-richness) or there might be molecular mechanisms that actively recruit the transposon/transposase complex at specific re sites [ – ]. curiously, the frequency of re elements in the first-generation transposon library and its weighted control were comparable. differently from the sa (obtained in % venus expressing immortalized keratinocytes without selective pressure), the first- generation transposon library derives from transposed hela cells [ ] selected for two weeks by antibiotic resistance. this culture condition could negatively select those integrations landing into poorly expressed genomic loci or into heterochromatin regions [ ]. nevertheless, the first-generation transposon integrations were slightly increased into satellite regions and sine, whereas ltr and dna elements were underrepresented compared to the background. these data identify some common features in sb datasets. conversely, mlv and hiv-derived viral vectors disfavour integration in re (satellite, ltr and line accordingly also to [ ]) suggesting an active role of viral integrase in the selection of integration sites that could better support the expression, replication and survival of the viral progeny. the genomic features newly identified in the sa integrome raise an interesting matter that needs to be deeply investigated for future application. supporting information figure s transposition trend. expression of venus fluorescence protein was detected by cytofluorimetric analyses at different time points in hela cells (a) and in gabeb cells (b). the days post transfection (p.t.) are plotted on the x axis, while the percentage of venus+ cells are represented on the y axis. the maximum expression from a transfected reporter gene was achieved days p.t (black vertical dotted line). the plot shows the samples co-transfected with sb x and transposon plasmids: t . or the sa . (blue), t or sa . (green), t or sa (purple), and the kb transposons (orange). sa constructs represented with dashed lines, t with continuous lines. in gold are represented the negative controls transfected with t . or sa . alone, without the sb x plasmid. (eps) table s list of primers used for plasmid episomial amplification, lm-pcr, and site-specific amplification of the sa-genome junctions. (doc) table s transposed clones were analysed to show the following parameters: number of retrieved venus + clones for each bulk; percentage of venus + cells in bulk populations hours p.t.; percentage of stable venus expressing cells in bulk populations; percentage of clones positive for the ampicillin or sb x sequence carried by transfected plasmids; mean copy number retrieved by southern blot analysis; recombinant events detected in transposed clones by southern blot analysis. (doc) acknowledgments we thank davide pietrobon for compiling the scripts used for filtering and trimming the raw sequences from sb and viral libraries. author contributions conceived and designed the experiments: gt mcl. performed the experiments: gt mcl. analyzed the data: gt mcl cc agd fm z. izsvák z. ivics ar. wrote the paper: gt ar. references . mates l, chuah m, belay e, jerchow b, manoj n, et al. 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( ) correction: genomic analysis of sleeping beauty transposon integration in human somatic cells. plos one ( ): e . https://doi.org/ . /journal.pone. published: january , copyright: © turchiano et al. this is an open access article distributed under the terms of the creative commons attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. https://doi.org/ . /journal.pone. http://www.ncbi.nlm.nih.gov/pubmed/ https://doi.org/ . /journal.pone. http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf&date_stamp= - - http://crossmark.crossref.org/dialog/?doi= . /journal.pone. &domain=pdf&date_stamp= - - https://doi.org/ . /journal.pone. https://doi.org/ . /journal.pone. http://creativecommons.org/licenses/by/ . / corr . .j.cb. . cell biology ; ( ): - published online may , (http://www.sciencepublishinggroup.com/j/cb) doi: . /j.cb. . issn: - (print); issn: - (online) most beautiful pigeons of bangladesh m. ashraful kabir lecturer in zoology, cantonment public school and college, saidpur cantonment , district- nilphamari, bangladesh email address: ashraful_wb@yahoo.com to cite this article: m. ashraful kabir. most beautiful pigeons of bangladesh. animal and veterinary sciences. vol. , no. , , pp. - . doi: . /j.cb. . abstract: pigeons are not aristocratic bird but its body shape, colorful feathers, ornamentation, care, mode of breeding; availability and cost seem to be aristocratic. from the very beginning of human welfare there existed a good relation between pigeon and human. at the dawn of human civilization pigeons are used as letter sending. later on its tumbling is another great point for its peculiar life. these birds are more social, lovely and sophisticated and found most of the houses in rural and urban areas. observed seven very nice pigeons are- western crowned pigeon, fantail, jacobin, frillback, pouter, trumpeter and swallow. their breeding is not normal as local pigeon except fantail. though the western crowned pigeon is wild but in captivity its breeding and maintenance is not bad. though these pigeons are produced fewer squab but only - pair in a year is shown great economic value. mentioned pigeons are chosen by peoples only on ornamental feathers except the enlarge crop of the pouter. observed some pigeons are reared in aristocratic family of the famous people or for research affairs so that it can be easily considered as aristocratic ones. jacobin pigeon was the best to queen victoria. in america, trumpeter is one of the most popular breed to all. moreover, emperor akbar reared fantail and pouter pigeons with other pigeons and naturalist charles darwin established a pigeon farm in his yard for explain his book ‘variation of plants and animals under domestication’. from the history the frillback is called darwin pigeon. pablo picasso and gypsy rose lee like fantail pigeon and johnny otis is famous for swallow pigeon collection. out of seven breeds only crown pigeon and frillback evolved by natural selection and others from artificial selection by judicious breeding. except fantails other six pigeons need to foster pigeons for its squab rising. keywords: fancy pigeons, beautiful pigeons, crowned pigeons . introduction in bangladesh perspective some fancy pigeons especially crowned pigeon, jacobin, fantail, pouter, swallow, bokhara trumpeter and frillback are reared as expensive items and it have aristocratic lifestyles. a study of kabir in showed that the most costly breed is frillback and the grading of this pigeons was a + in fantail and capuchine and pouter and frillback were a. care of these pigeons is more sensitive than others and is accepted by everybody for nice feathers. but one great problem is that its breeding performance especially egg laying and from hatching to fledging is not good. for avoiding such situations some foster pigeons (tumblers) are used. for one pair beautiful pigeon minimum five pair fosters is needed. though this is a problem to maintain those foster parents for rearing those fancy items but at present there is no way. moreover, need to ensure the similar date for egg laying of foster pigeons. otherwise, it not showed the regurgitational activity to the young. above pigeons were reared at the time of mughal dynasty. emperor akbar had selected pigeons with fantail, jacobin and pouter but in ain-i-akbari which translated by blochmann in there distinct breeds were only nine and other descriptions were not clear. that time all breeds are bred in court and its feed were grains. its care was more sophisticated so that rearers are got more benefit from those breeds’ squab. lot of scientific and proper care is important than other breeds. in these pigeons for ornamental feathers which are the barriers for its normal breeding. so, trimming of the head-feather, leg and tail region is must in some cases. for the huge ornamentation of feathers those pigeons can’t fly properly. so, it is easily maintained in a balcony or narrow space of the residence. later on in america and england is performed huge research on fancy pigeons and produced lot of varieties with its proper identifying points. mr. levi in who was army personnel described in his book ‘the pigeon’ deals various corners of the pigeons with aristocratic one and he divided the fancy pigeons into four major groups- fancy, animal and veterinary sciences ; ( ): - utility, racing and flying. charles robert darwin in in ‘the variation of animals and plants under domestication’ mentioned the four major evolutionary groups of pigeons. he noted pouter in group ; fantail, indian frillback and jacobin in group and swallow, trumpeter and english frillback in group . . materials and methods huge ornamentation of the feathers mainly in head-region some breeds can’t see well. this is the main barrier for breeding performance. secondly, the muffed is adverse for its walking and the excess tail-feather and its expansion are the cause of non-fertile eggs. so, need to trim those feathers mainly in breeding season of that beautiful pigeons. table . following pigeons with their origin and selection english name origin type of selection western crowned pigeon australia natural selection fantail india artificial selection jacobin india artificial selection cropper/pouter india artificial selection swallow germany artificial selection bokhara/trumpeter turkey, mid asia artificial selection frillback asia minor natural selection . results and discussion . . western crowned pigeon types: victorian, southern, western. characteristics: this is large, blue-grey pigeon with blue crest and dark blue mask feathers around its eyes. this bird is very similar with victoria and southern crowned pigeon. it is one of the largest and is considered most beautiful members of the pigeon family. average length is inches. breeding: the female usually lays a single white egg (plate ). plate . western crowned pigeon . . fantail types: indian, english, american, silky. characteristics: indian fantail: it varies in size and tremulous of the neck. mostly white and overall tail feather or rectrices are thirty plus. muffed are medium in length or none. generally indian fantails are long and mostly crested. some are black, tigered, spotted, patches and tip of the tail back with white bodied. occasionally it appears small in size and wild type head. tail feathers are overlapping and not well arranged. non- tremulous varieties are common. english fantail: this is small in size and non-muffed. its head is wild type and always attach to the tail with huge tremulous. tail feathers are few but well arranged. it always stands on feet and in bangladesh this breed is not available. white bodied with coloured tail is common in this breed. beak is medium and head is small. in scotland the fantails are considered only on carriage but in english this is expanded-tailed breed (mcneillie, ). american fantail: american fantail resembles indian fantail. head touch with the tail and tail feathers are or above. not muffed and crested. tail feathers are semicircular and well arranged. in bangladesh some indian fantails or its crossed variety is sold as american fantail. normally this is large in size and legs are short; body not elongated and stands on tiptoe. silky fantail: probably the first picture and description of a silky fantail was by john moore in his columbarium ( ). linnaeus also described and named the silky pigeon in the th edition of his systema naturea ( ). he called it columba hispida (from the latin word hispidus=rough, hairy). charles darwin ( ) was familiar with silky plumage in pigeons as well, and he knew it was a variety. the barbules of the feather do not lack hooks and elasticity is very poor. silky pigeons can not fly because of their feather condition. breeding: sometimes this breed is called garden dovecote or peacock pigeon. in bangladesh the production of fantail is not bad. most of the cases rearer provides some vitamins for its proper breeding. its squab producing is same as common pigeon. its white colour and fan-like tail is attractive to the breeder so it gets more benefits for its caring. maximum tail feathers are thirty plus and minimum were and tail feathers are less expanded so that mating is as usual. caudal and neck muscle shows contraction and expansion so that tremule of the neck and up-down of tail is happened. more expanded tailed birds need to cut - feathers from male and female. if male is large and tail feathers are not well arranged its mating is okay and eggs are being fertilized without cutting the tail feathers (plate ). plate . fantail . . jacobin types: clean-legged, muffed. characteristics: this is also called wig pigeon (mcneillie, ). clean leg; slender and sleek; horizontal and ‘l’ shape between neck and tail; head is white until half to three-quarters of an inch; hood present; m. ashraful kabir: most beautiful pigeons of bangladesh elongated wing and tail. breeding: jacobins will be mated up around the end of july. breeders will cut the hood and surrounding vent feathers to allow more efficient mating. the hood is so large that it can interfere with mating. jacobin has too short beak have trouble to feed its young. foster parents such as homers are usually used to hatch and raise jacobin chicks. head is covered with long manes so predator animals get a chance to attack easily (plate ). plate . jacobin . . cropper/pouter types: brunner, english, pygmy, ghent, norwich, old german, dewlap. characteristics: when it flies a clapping sound happens by shifting the tail and wing and its upper oesophagus is large (mcneillie, ). balloon and enlarge crop is elongated; staying in two legs like a man; much elongated body, wings and legs. breeding: foster parents are required for its proper output. while feeding special attention must be taken and include enough grits in their diet for proper digestion (plate ). plate . cropper/pouter . . swallow types: nuremburg, saxon, fairy, spotted, tiger. swallows are of two types- fairy swallow and swallow proper. fairy swallow is performs fly (mcneillie, ). characteristics: these are mainly muffed and crested- known as ‘color pigeons’; always similar to the white pigeon with colored wings; low standing pigeon; marking to the tern bird; edge of the mouth is red; leg is short; body shape is resemble wild rock pigeon. breeding: in usa and britain the muffed and crested varieties have gained the greatest popularity while in germany clean-legged are more popular (plate ). plate . swallow . . bokhara rose/russian trumpeter types: english, bokhara (turkey), double crested, bernburg, dresden, german, altenburg. characteristics: long and large-sized pigeon; nice rose-crest and muffs are fan-like measures - inches (mcneillie, ); coo voice; legs are vulture-hocked. breeding: for proper breeding need to trim crest and leg feather (plate ). plate . bokhara/trumpeter . . frillback types: indian and english (darwin ). characteristics: curled feather all over the flights and tail; the flights and tail are only slightly altered; eye gravelly-red; feather form conical hollow; light flight. breeding: its curly feathers are caused for autosomal dominant mutation. all the chicks from a cross of a double dominant frillback to another breed would produce slightly frilled offspring; recessive shell crest and feathered legs. a cross of a double dominant frillback to another breed would produce slightly frilled offspring (plate ). plate . frillback animal and veterinary sciences ; ( ): - . conclusion in bangladesh among seven types of the most beautiful pigeons the fantails are the class one which is common in every rearers. attractive body shape and feathers are easily snatched by people. secondly the pouter is common. the demand on fantail pigeon is showed year-round and its breeding is as usual. all breeds have lower parental bondage so need to rear foster parents. if only - pair squab rises in a year that’s enough for the benefit. need to trimming some feathers from tail, head, neck and leg regions for proper vision as well as breeding. only adult pair is reared separately and the squab with aged - months for selling need not trimming. all beautiful pigeons have elongated body, large size, expanded tail, great mane, frilled feathers, swollen crop, muffs and double rose-crested. these breeds are more or less pure because they have no similar breeds in bangladesh. for huge profit and commercial view these ornamental pigeons are really different than others. fanciers reared these pigeons in totally intensive system. only crowned pigeon is reared in aviary. in future we should maintain extra care and more scientific study on these beautiful pigeons. . acknowledgements author is giving cordial thanks to his favourite student ‘onu’ who is one of the keen pigeon rearers in dhaka, bangladesh. he is also a great visitor in every fancy pigeon market in dhaka. author is informed huge fancy pigeon rearers in dhaka as well as on crowned pigeons. he always contacts with other experienced pigeon rearers of the country for his knowledge on fancy pigeons. writer of this paper is collected information from saidpur (crossed fantail), dinajpur (pouter, jacobin, swallow, bokhara) and kushtia (frillback). during the time of this study huge pet shops in dhaka, kataban were helpful for observing the characteristics of these pigeons with daily-routine in those shops and the rearers’ residences. plate photograph is collected from google.com and , and from www.bikroy.com. references [ ] blochmann h. . the ain i akbari by abul fazl allami. the asiatic society of bengal. vol : amusements by pigeon flying. [ ] darwin cr. . the variation of animals and plants under domestication. john murray, london. [ ] iucn red list of threatened species. version . . international union for conservation of nature. retrieved november . [ ] kabir ma. . productivity, management and marketing of pigeons in pet shop. j. agric. econ. dev. ( ): - . [ ] kabir ma. . grading system of ten common fancy pigeons of bangladesh. integrated j of british ( ): - . [ ] levi wm. . the pigeon. levi publishing co., inc., sumter, s c. [ ] linnaeus c. . systema naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in latin) ( th ed.). stockholm: laurentius salvius. [ ] mcneillie a. . pigeons of the world. a magna illustrated guide, leicester. [ ] moore j. . columbarium: or, the pigeon-house, being an introduction to a natural history of tame pigeons. london: printed for j. wilford. (a reprinting of this book is given by j. m. eaton in his ‘treatise’ .) uc santa barbara recent work title will small be beautiful? making policies for our nanotech future permalink https://escholarship.org/uc/item/ vd v dx author mccray, w. patrick publication date - - peer reviewed escholarship.org powered by the california digital library university of california https://escholarship.org/uc/item/ vd v dx https://escholarship.org http://www.cdlib.org/ history and technology vol. , no. , june , pp. – issn – (print)/issn – (online) © taylor & francis group ltd doi: . / will small be beautiful? making policies for our nanotech future w. patrick mccray taylor and francis ltdghat .sgm . / history and technology - (print)/ - (online)original article taylor & francis group ltd june assistant professorw.mccraypmccray@history.ucsb.edu. with the passage of the national nanotechnology initiative (nni) in , us investment in nanotechnology research and development soared quickly to almost us$ billion annu- ally. the nni emerged at a salient point in us history as lawmakers worked to reshape national science policies in response to growing international economic competition and the increasing commercialization of academic science. this paper examines how advocates of nanotechnology successfully marketed their initiative. it pays especial attention to their opti- mistic depiction of societies and economies improved by nanotechnology, and considers why utopian techno-visions continue to flourish despite their tendency to ultimately disappoint. keywords: nanotechnology; science policy; technological utopias it was as if nanotechnology had gone through a phase transition; what had once been perceived as blue sky research … was now being seen as the key technology of the st century. on october , california politicians, academics, and civic leaders attended the groundbreaking ceremony for the california nanosystems institute in santa barbara. this us$ million high-tech building, with its ultra-filtered clean rooms and modular laboratories, represented only a fraction of the burgeoning national investment in nanotechnology. since , when president william j. clinton announced a new national initiative to foster the tools of the ‘next industrial revolution,’ dozens of universities and corporations have initiated programs where scientists and engineers research phenomena and technologies at the nanoscale. following proclamations by clinton and other leaders, government and commercial investment into nanotechnology soared. in , federal agencies in the usa dispensed w. patrick mccray is an assistant professor in the history department at the university of california at santa barbara, usa. email: pmccray@history.ucsb.edu. he is the author, most recently, of giant telescopes: astronom- ical ambition and the promise of technology (cambridge, ma: harvard university press, ). he is currently engaged in a pilot research project that examines the recent history of nanotechnology with especial emphasis on science policy, community formation, public perceptions, and the collection of oral histories. w. p. mccray almost a billion dollars a year to eager researchers (figure shows the federal funding profile for nanotechnology research). meanwhile, forecasts, not from intemperate prognosticators but sober-minded science managers, predicted that the international market for nano-goods would be us$ trillion by . the production of these goods, supporters said, would require a new high-tech (and highly paid) workforce of some two million people, potentially leading to major restructuring of the global workforce. figure funding profile for nanotechnology research in the usa, – . total funding is shown along with monies allocated specifically to the national science foundation and the department of defense. figures are projected; breakdowns by agency not available for . source: roco, ‘the us national.’ to its advocates, nanotechnology is a ‘transcendent realm,’ a regime where research in the physical and biotechnological sciences may converge with information technol- ogies and the cognitive sciences. while definitions of what nanotechnology is vary— indeed, one of its rhetorical strengths would seem to be its interpretive flexibility—its basic feature is ‘smallness.’ according to official government definitions in the usa, nanotechnology involves three key components; research and technology development at the length scale of – nm; creating structures and devices that have novel prop- erties and applications because of their small to intermediate size; and the ability ‘to control or manipulate on the atomic scale.’ nanotechnology, in other words, is engineering done at the molecular scale and represents the ability to deliberately shape new structures, atom by atom. compared with the behavior of individual atoms or molecules (the latter being about nm in size) or the properties of bulk materials, the behavior of structures in the size range of a few to a nm is quite different. in this regime, the effects of surface area, interfaces, and figure funding profile for nanotechnology research in the usa, – . total funding is shown along with monies allocated specifically to the national science foundation and the department of defense. figures are projected; breakdowns by agency not available for . source: roco, ‘the us national.’ history and technology quantum behavior can create new behaviors and properties. because the nanoscale is where the basic structure of materials are established and their properties defined, advocates of nanotechnology predict the creation of revolutionary nanostructures from the ‘bottom up.’ if realized, the ability of nanotechnologists to shape materials and structures with atomic precision would be the culmination of humans’ expanding ability to manipulate their material world. humans, with varying degrees of intent, have been nanotechnologists for millennia. ancient artisans have consciously manipulated metal, glass, and ceramic materials to create certain properties. consider the lycurgus cup, a th-century glass vessel in the collection of the british museum. the object’s unusual optical properties are caused by a haphazard dispersion of nanometer-sized particles of a gold–silver alloy in a glass matrix. nanotechnology’s potential, its advocates claim, rests in its promise for precise control. in their view, it offers the ability to organize atoms and molecules into usable novel materials, structures, or systems with physical, chemical, and biological proper- ties that are either known or predictable via sophisticated computer modeling. the marshalling of congressional support for the national nanotechnology initia- tive (nni) occurred against the background of post-cold war (and, later, post- september ) science and technology policies. proponents of nanotechnology offered seductive visions of a tomorrow that appealed to citizens, scientists, and policy makers, visions that this article examines. as one nobel laureate said in a government brochure designed to make nanotechnology visible to the public, ‘nanotechnology has given us the tools … to play with the ultimate toy box of nature … . the possibilities to create new things appear endless.’ in testimony to congress and in books written for the public as well as science and policy communities, technological visionaries and science administrators alike predicted that nanotechnology could ‘change the nature of almost every human-made object in the next century’ and, in doing so, not only alter our ‘comprehension of nature and life … [but] even influence societal and international relations.’ these predictions, in turn, helped spur lawmakers to allocate billions of dollars for research and commercial development. despite arguments from skeptics attempting to re-direct policy and commercial research and development efforts, government leaders eventually adopted and ratified these utopian predictions in national science policy when they approved the national nanotechnology initiative in . the sheer dollar amount, the rapidity of the funding increases, and the accompany- ing flood of books, websites, and pop culture references to what one author called the ‘nanocosm’ are sufficient to command attention from a wide array of disciplines in the academy. while scholars have made initial efforts to analyze the economic, social, ethical, and legal challenges posed by the predicted ‘next wave’ of technological innovation, historians have paid comparatively little attention to nanotechnology. while this lacuna is understandable as nanotechnology’s potential benefits still reside largely in research laboratories (the major commercial products exploiting nanoscale research thus far are stain resistant pants and improved cosmetics), the relative dearth of historiography concerning nanotechnology with which one can engage makes the historian’s task more difficult. it is too early to assess the economic or societal effects of w. p. mccray nanotechnology; it is not premature, however, to examine the roots of and rationale for the united states’ massive investment in the nanocosm. this article is therefore to be read as an exploratory reconnaissance of the funding and policy terrain of nanotech- nology in the last decade and is written with the understanding that future documen- tation will add much more depth and detail to the story presented here. what is required to create a successful new science initiative? previous studies of policy-making for science have identified several variables for victory. these include the role of entrepreneurs who lobby for policies that support their goals as well as perceived national needs. coordinated activity among agencies, interest groups, and researchers as well as budgetary and institutional contexts are other factors. howard mccurdy, in his discussion of how americans imagined space exploration, rightly notes that public policy also has an important subjective dimension whose roots are located in imagination and visions of the future. why was the nni successful in obtaining so much federal support and what was its ‘subjective dimension’? this article addresses the area where, in the late s, utopian imaginings and policy rationales met fiscal realities. national science policy is frequently analyzed through, if not indeed seen as commensurate with, the politics and annual changes of science budgets. this article goes beyond the conflation of policies with budgets to explore how and why such monies were allocated. in describing how advocates for the nni gradually orchestrated its funding, this paper offers a historical perspective on the promotion of a major national initiative to support nanotechnology in the usa. in looking at the rationales offered by lawmakers and science managers, i pay special attention to the depiction of future nano-utopias in support of policy goals. historians will recognize the marshalling of techno-utopian visions as a theme common to the history of many technologies. from household appliances to nuclear power and the internet, the introduction of new technologies has often been accompa- nied, if not presaged, by wildly optimistic claims and unbridled enthusiasm. more often than not, enthusiasts and supporters of new and ‘revolutionary’ technologies have seen their predictions tempered by fiscal, social, or regulatory realities. the belief that the next industrial revolution will come from nanotechnology existed in conjunc- tion with other more prosaic rationales, some relics from the cold war, for funding the nni. besides considering how advocates promoted the nni and how its funding reflects broader changes in national science and technology policy, it is important to ask why utopian techno-visions continue to flourish given their predilection to ultimately disappoint. before the flood historians of science and technology have long recognized the existence of ‘creation stories,’ myth-like narratives for research communities that trace the development of a particular idea or invention back to a singularity—lone inventor or small teams who create a revolutionary breakthrough. for geneticists, there is watson, crick, and the double helix; for electrical engineers, shockley, brattain, and bardeen’s invention of the transistor looms large. history and technology nanotechnologists’ creation story can be traced to a precise point in space and time—the evening of december when caltech physicist richard p. feynman gave an after-dinner speech in pasadena to members of the american physical society. feynman, one of the most original physicists of the th century, gave his address, whimsically entitled ‘there’s plenty of room at the bottom,’ at a time when the mass production of microelectronics was just beginning and computers still occupied entire rooms. feynman described the potential benefits of ‘manipulating and controlling things on a small scale’, which he believed could be accomplished while still obeying the basic laws of physics. scientists, he predicted, would build microscopic machines that could manipulate matter at a very small scale while engineering done at the ‘bottom’ would provide plenty of attractive research opportunities. human control of matter at the atomic scale was, according to the caltech physicist, a ‘development which i think cannot be avoided’ and he backed up his assertion by offering a thousand dollars ‘to the first guy who can take the information on the page of a book and put it on an area / , smaller in linear scale in such manner that it can be read by an electron micro- scope.’ in his talk, feynman drew upon utopian visions proffered by contemporary fiction writers, which suggested, ironically, how the scientific and visionary aspects of nanotechnology were interconnected from its very beginning. feynman never did any research that could be construed as nanoscience. indeed the word ‘nanotechnology’ did not appear until and then in an obscure proceed- ings of a japanese industrial conference. nevertheless, feynman’s address became a crucial touchstone for future advocates of nanotechnology. in both popular treatments as well as policy documents, quotations from it are rampant while feynman’s author- ship serves as a rhetorical anchor to scientific authority. this critical linkage was strengthened by the fact that feynman later shared the nobel prize for his research on theoretical quantum electrodynamics. according to what some have appropriately called the ‘standard story’ of nanotechnology, feynman presented the crucial initial vision of the innovative nano-research that scientists could do, the achievement of which only required the proper tools. these tools—namely new and improved electron microscopes—were incrementally developed by scientists and engineers during the s and s. this led to the next milestone in the ‘standard story’ that helped set the stage for the eventual promotion of a national nanotechnology initiative. in , gerd binnig and heinrich rohrer, researchers at an ibm research laboratory in zurich, received the nobel prize for their design of the scanning tunneling microscope. with a properly functioning instrument (the achievement of which is still something of a black art), researchers now had the ability to ‘see’ individual atoms as their probe scanned a sample’s surface and rendered an image of its topology on a computer screen. now able to image atoms, the next milestone in realizing feynman’s now-mythic vision was the ability to move them. in a paper published in nature, two research- ers reported that they had manipulated individual xenon atoms on the surface of a single crystal of nickel cooled to almost absolute zero with ‘atomic precision.’ in their demonstration of the ability to ‘fabricate rudimentary structures of our own design,’ w. p. mccray eigler and schweizer honored their corporate sponsor by using xenon atoms to spell ‘ibm.’ a major article in the new york times followed in which a reporter described how he laboriously moved about a few atoms with eigler’s coaching. engineering at the nanoscale, as the times described it, was not only potentially ground breaking but entertaining—as eigler wrote in his lab notebook entry, ‘i am really having fun!’ stunts like this made international headlines and provided the capstone to feynman’s roadmap—in principle, researchers could now organize matter as well as see at the atomic level. however, doing so was still a challenging enterprise that required a good deal of expensive equipment, tacit knowledge, and specialized skills. while a new community of electron microscopists coalesced around the new tools and tech- niques in the late s and early s, much of this happened out of sight from the larger scientific community and the general public. another element, one that feynman did not account for, was needed: a messenger to boldly proselytize for nanotechnology. in the s, k. eric drexler emerged as the most visible and vocal proponent of nanotechnology and its transforming potential. born in , drexler attended mit and, while working at that school’s space systems laboratory, wrote a paper that outlined his early vision for nanotechnology. he argued that the ability to design protein molecules could lead to the manufacturing of molecular machines that, in turn, could make ‘second-generation machines’ and the ‘construction of devices and mate- rials to complex atomic specifications.’ drexler went on to teach the first university course on nanotechnology, published an equation-laden textbook on the subject, and was a co-founder of the foresight institute, a non-profit group devoted to promoting the benefits of nanotechnology. the first full articulation of drexler’s nano-utopia was his book engines of creation. written for the general public, drexler’s book considered the potential bene- fits and risks arising from the wholesale production of nanomachines. at the heart of his vision was what drexler called ‘assemblers,’ hypothetical autonomous machines, protein-sized or smaller, that could produce virtually any material or object. such ideas were incorporated by science fiction writers who imagined a future in which a person had access to a ‘utility fog’ from which they could call forth the material necessities of life. while skeptical, one review of drexler’s book described it as a ‘hopeful forecast, remarkable for an unembarrassed faith in progress through technology.’ a full treatment of drexler’s activities and the attention they received is beyond the scope of this paper. it will suffice to say that a article in science called drexler ‘the apostle of nanotechnology’ and noted that he was already a lightning rod for praise as well as vitriolic scorn from fellow scientists. criticisms came from both science journalists and other researchers, with the detractors claiming that drexler’s vision of self-assembling nanomachines not only drew attention (and possibly funding) from actual lab-based endeavors but also would violate basic laws of conservation. refer- ring to drexler’s missionary zeal and the fervor he inspired among his supporters, one critic said, ‘you might as well call it nanoreligion.’ however, for the sake of promoting research and development of nanotechnology to the top of the national agenda, drexler and other nano-advocates performed an important function. in promoting radical futurist scenarios, which his critics placed in history and technology the realm of fiction rather than science, drexler and his colleagues brought nanotech- nology to the attention of policy makers. as such, drexler and company may be consid- ered the vanguard of a wave that eventually brought potent government support for more conventional and staid research programs devoted to nanotechnology. this was not long in coming. in june , senator albert gore, recently returned from the united nations earth summit in rio de janiero, convened a congressional hearing devoted to ‘new technol- ogies for a sustainable world.’ drexler was one of the witnesses invited to appear before gore’s subcommittee. he testified that ‘molecule-by-molecule control,’ which nanotechnology suggested, could become ‘the basis of a manufacturing technology that is cleaner and more efficient than anything we know today.’ nanotechnology, drexler argued, certainly met ‘the criteria for an environmentally critical technology.’ gore, for his part, displayed great enthusiasm for drexler’s ideas and his knowledgeable reference to feynman’s speech also confirmed that nanotechnology’s creation myth still possessed great currency. like many predictions of technological utopias, drexler’s congressional testimony says more about contemporary circumstances than it makes accurate statements about the future. drexler’s pronouncements resonated with concerns held by american poli- ticians and the public about the environment, sustainable development, and american economic competitiveness. it depicts a future ameliorated and achieved through the adoption of a ‘technological fix,’ one where nanotechnology would raise ‘the material standard of living worldwide, while decreasing resource consumption and environ- mental impact.’ drexler’s appearance marked the most visible discussion yet on capitol hill of nanotechnology as a potentially valuable area for federal investment. topics that politicians care most about—health, the economy, and national security—all looked to benefit from nanotechnology. while yet a minor blip, nanotechnology was now on the federal government’s radar screen. planting the flag the utopian nano-futures portrayed by drexler and others garnered a great deal of attention in the early s, and the claims could be quite extravagant. in , a nano- enthusiast claimed that nanotechnology could even produce immortality. conse- quently, many scientists and science writers were skeptical if not openly derisive and hostile toward such visionary claims. in his review of the book nano! remaking the world atom by atom, chemist david e. h. jones, for example, concluded that until scientific questions surrounding the most optimistic claims of nano-enthusiasts were answered, nanotechnology itself would ‘remain just another exhibit in the freak-show that is the boundless optimism school of technical forecasting.’ perhaps more seriously, other critics noted that advocates who promised great benefits from nano- technology and drew on feynman’s reputation for their scientific authority were squandering the political and social capital accumulated by real scientists who were doing actual laboratory work. w. p. mccray scientists were clearly expending a great deal of effort to establish distinct bound- aries between what they saw as legitimate research and nano-visions that seemed to have more in common with science fiction than laboratory realities. in order to gain access to the resources, i.e. funding from the federal government and industry they believed necessary to pursue a full-scale research program in nanotechnology, a compelling vision for nanotechnology needed to be articulated by people not on the fringe of the research establishment. mihail c. roco was a key person who took the stage in the mid- s determined to strip nanotechnology of its exaggerated claims and to promote an ambitious, realistic nano-research program as a national priority. born in in bucharest, roco was a mechanical engineer who came to the usa in , where he carried out research at a number of institutions before joining the national science foundation (nsf) in . ‘captivated by the unity and coherence encountered in nature,’ roco wanted to like- wise promote the ‘coherence of science and technology.’ soon after joining the nsf, he helped create a new, modestly funded program that investigated the synthesis of nano-sized particles. gradually, roco began to lay the foundation for a much more ambitious inter-agency program that would support a whole range of research in nanotechnology. roco launched his entrepreneurial plans at a promising time. following the end of the cold war, there was much debate among scientists, policy makers, and govern- ment agencies about how to restructure us science policy. there was general agree- ment that that us science policy needed revision yet achieving consensus on how best to do this was difficult. national defense against a monolithic communist threat no longer served as sufficient justification for funding basic science. just as significantly, the end of the cold war signaled to policy makers that the next arena of conflict would be in the global marketplace in the form of increased economic competition from european and asian countries. this was an especially salient fact to us lawmakers who read reports of how japanese and european companies were taking the basic research done in american laboratories to the global marketplace and profiting hand- somely in the process. in , japan’s ministry of international trade and industry pledged some us$ million for nanotechnology, with research aimed at benefiting that country’s electronics industries. news like this fed existing fears among corpo- rate and government leaders that the us was falling behind in a potentially key economic area and spurred more calls for a revamped national science policy in the wake of the cold war. articulating an appropriate policy to deal with this competitive threat from abroad became a priority for lawmakers and policy analysts. more than half a dozen major reports appeared that suggested how to re-structure us science policy in response to the new global environment. solutions included improving america’s publicly funded research infrastructure and investing public monies in technologies whose benefits were only on the horizon. while not named as such, advocates soon touted nanotechnology as one of these under-supported fields with great potential. many of these suggested changes were embraced in the first official review of us science policy in the post-cold war era. science in the national interest, released in history and technology august , described basic research and technological development not as the keys to national security but as elements that ‘underpin the nation’s economy.’ gore stated, in words reminiscent of vannevar bush’s half-century old vision, ‘technology is the engine of economic growth; science fuels technology’s engine.’ us science policy, the report said, should enhance connections between fundamental research and national goals and one of these goals was, of course, long-term economic growth. compared with the structured plans put forth by the japanese, the us effort in nano- technology was under-funded and disorganized. for example, since , the nsf had funded the national nanofabrication facility at cornell university. the us$ million facility served as a place where researchers from around the country could come to do research and use equipment their home institutions lacked. the national institute of standards and technology also began an initiative in nano-research. given these disparate initiatives, which in toto were spread over different agencies, roco and others claimed that the us lagged behind other countries when it came to a major national investment in nanotechnology. as a first step in coordinating the people, infrastructure, and funding for nanotech- nology research in the us, roco, along with richard siegel (rensselaer polytechnic institute) and evelyn hu (university of california at santa barbara), organized a work- shop in arlington, virginia. this meeting was held under the auspices of the world technology evaluation center (wtec), formerly known as the japanese technology evaluation center. charged with examining foreign research in selected technology areas and operated out of loyola college in baltimore in cooperation with the nsf, wtec provided information for policy makers concerned about american industrial competitiveness. the wtec meeting marked the beginning of an effort to ascertain research trends in nanotechnology worldwide. roco claimed that nanotechnology was at ‘a level of development comparable to that of computer/information technology in the s’ yet was poised—with sufficient funding—to become a key emerging technology for the st century. at the meeting, attendees described the current level of us spending on nanotechnology—in fiscal year , this was us$ million with more than half of the money coming from the nsf—and emphasized the need for interagency collabo- ration. the report roco and his colleagues prepared also noted that governments in japan and europe were already funding comprehensive programs. however, compared to the far-reaching and visionary claims by drexler and other nano-utopi- ans, the soberly written wtec report served to clarify the current state of nano- research rather than promote nano-utopian visions. after the may meeting, roco helped form an interagency working group on nanoscience, engineering, and technology (iwgn) which he chaired. the iwgn answered to the cabinet-level national science and technology council established by president clinton in . throughout , the iwgn met and worked out a vision for what ultimately became the national nanotechnology initiative. like all major government initiatives, putting the pieces in place took a great deal of time and coalition building. w. p. mccray while roco and his colleagues were formulating their proposal for the nni, the us government reviewed its investment in scientific research yet again. in february , soon after the second clinton administration began, house speaker newton l. gingrich asked the house committee on science to develop a long-range science and technology policy. the committee’s report, released in september , reaffirmed that, with the end of the cold war, the principal contributions of science and technol- ogy would not be for national defense but economic competitiveness. as gingrich framed it, ‘the competitions we are engaged in now are less military and largely economic.’ the report also articulated aspects of america’s new ‘mega-era’ of science policy that advocates of the national nanotechnology initiative soon embraced. grants to individual scientists and engineers were the ‘primary channel by which the government stimulates knowledge-driven basic research,’ while the research done at universities and national laboratories must be continually ‘applied to the development of new products or processes,’ so as to further strengthen linkages between university laboratories and commercial ventures formed after the passage of the bayh–dole act in . just as significantly for the success of the nni, the report acknowledged that private industry was unlikely to fund areas like nanotechnology that had no foreseeable practical application; this role would therefore devolve to the federal government. as members of congress re-examined national science policy, several prominent people joined the campaign for a national nanotechnology effort. at this point, as the push for the nni’s funding intensified, the first noticeable traces of nano-utopian visions crept into the rhetoric of scientists and administrators. in april , neal lane, president clinton’s science advisor, appeared before the house basic research subcommittee. lane, whose specialty was theoretical atomic and molecular physics, made a statement that was to be widely quoted: ‘if i were asked for an area of science and engineering that will most likely produce the breakthroughs of tomorrow, i would point to nanoscale science and engineering.’ noting how nsf support had enabled nanotechnology to transform ‘from the realm of science fiction to science fact,’ lane went on to describe ideas that drew as much from the former as the latter: nano-sized medical probes, new classes of materials, and—straight from drexler’s writings— ‘nanomanufactured objects that could change their properties automatically or repair themselves.’ as lane put it, the ‘possibilities of nanotechnology are endless.’ on march , roco formally presented plans for the national nanotechnology initiative to neal lane and thomas kalil, clinton’s deputy assistant for technology and economic policy. during their two-hour meeting, roco described an initiative for fiscal year costing some us$ million. at the end of the meeting, nanotechnol- ogy won out over competing initiatives and now had two well-placed advocates in the white house. according to roco, the next task was to educate both the public as well as congress as to what nanotechnology was and what it could offer. a glossy brochure entitled nanotechnology: shaping the world atom by atom made the case to the public and drew upon nano-utopian rhetoric that was rapidly becoming de rigueur—the vision of feynman’s talk, the progress made in manipulating atoms via electron history and technology microscopy, the potential to fabricate nanoscale electronic devices, the now-famous ibm logo writ in xenon atoms, and the vast commercial and societal benefits that investment in the nni could open up. congress still required persuading, however. on june , the house of repre- sentatives’ committee on science met to review the federal government’s support of nanotechnology and to discuss its potential economic implications. chairman nick smith opened the meeting by noting that the united states did not dominate nano- technology. ‘how much effort,’ he asked, ‘should the federal government be putting into tax-payer funded research in this area?’ several witnesses answered chairman smith; all drew in some capacity upon the utopian visions of nanotechnology’s potential that had been gestating for over a decade. of those who spoke that afternoon, chemist richard e. smalley of rice univer- sity was perhaps most persuasive. smalley was a co-discoverer of carbon- molecules, better known as ‘buckyballs,’ for which he had shared the nobel prize. buckyballs were closely related to carbon nanotubes that japanese scientists had discovered in , and advocates of nanotechnology referred to these new structures as clear exam- ples of how matter could be deliberately controlled at the atomic level. ‘there is a growing sense in the scientific and technical community,’ smalley told congress, ‘that we are about to enter a golden new era.’ citing his own experience battling cancer, smalley connected research at the nanoscale with an array of societal benefits that could result, including medical breakthroughs. the nobel laureate shrewdly pointed out that research in nanotechnology was ‘intrinsically small science.’ because research in nanoscience was not centralized in one or two national laborato- ries, funding the nni would combat the trend towards ‘big science,’ offering a way to fund individual researchers. funding ‘small science’ (in both senses) would, smalley argued, help attract students into science careers just as sputnik’s launch in had inspired his generation. the nni, smalley avowed, would also support broader national policy goals. ‘there’s this immediacy between the ivory tower pure scientist and the technologist’ in nano-research, smalley said, and the nni would simultaneously strengthen both while creating valuable linkages between basic research and commercial applications. nanotechnology, smalley concluded, presented a ‘tremendously promising new future.’ what was needed was someone bold enough to ‘put a flag in the ground and say: “nanotechnology, this is where we are going to go …”.’ in urging congress to fund a major national initiative for nanotechnology, advo- cates of the nni deployed an array of effective arguments, some new and some already familiar: the specter of economic competition with europe and japan; the opportunity to recruit a new generation of scientists and engineers; and support for traditional individual, peer-reviewed research rather than giving a handout to a few giant national laboratories. persuasive utopian images and frontier metaphors were added to the rhetorical brew. one witness that afternoon, for example, compared nanotechnology with kennedy’s declaration to put a man on the moon. what the usa needed to do, advocates insisted, was to be bold once again and plant a flag on a new frontier. w. p. mccray the floodgates open richard smalley and the others who testified in june were largely pushing against an open door as they made their case for a major national investment in nanotechnol- ogy. reflecting new ideas in circulation about national science policy, questions from congressional representatives were more praising of nanotechnology than they were probing. such enthusiasm is understandable as the house committee that heard smalley and others was convened to gather information, not appropriate tax-payers’ money. congressional questioning would become more intense once real dollars were at stake. roco and other nni advocates focused their efforts next on federal agencies such as the nsf, nasa, and the department of defense, which would likely administer fund- ing for a major new initiative. by november , the office of management and budget and the white house were studying plans for the nni. that same month, the presidential council of advisors in science and technology (pcast) issued its formal review of the proposed nni. more circumspect in its espousal of the now-familiar utopian predictions for nanotechnology, pcast nevertheless identified nanotechnol- ogy as a potential path to a ‘new industrial revolution,’ one that might lead to unfore- seen advances in ‘materials and devices of all sorts … medicine and health, biotechnology and agriculture, as well as national security.’ in an increasingly famil- iar comparison, nanotechnology was likened to the state of solid-state physics research in the s but, unlike the lead that america enjoyed in transistors and microchips when their commercialization began, the usa lacked ‘an early lead in nanotechnol- ogy.’ pcast argued that the usa could not afford to be in second place: ‘the country that leads in discovery and implementation of nanotechnology will have great advan- tage in the economic and military scene for many decades to come.’ the nni, there- fore, represented an opportunity to swiftly create an infrastructure for nano-research and perhaps avoid the precarious state the usa found itself in during the s when fears of japanese technological supremacy ran rampant. a subsequent letter from the pcast to president clinton offered firm and clear support of the nni. with these endorsements in hand, president clinton traveled to pasadena, california where he addressed a standing-room only crowd at caltech’s beckman auditorium. on january , clinton articulated the need to strengthen america’s investment in science and technology. after paying homage to caltech and feynman (as well as an image suspended above him of the western hemisphere constructed with individual gold atoms), clinton announced the inclusion of a us$ . billion ‘twenty-first century research fund’ in his budget, which was an element in a larger strategy to double the nsf’s budget over the next five years. a ‘top priority’ was a major increase in the nsf’s funding for nanotechnology—over % or us$ million in the next year alone—which, when combined with funding for other agencies, would nearly double the federal investment. clinton rhapsodized just imagine, materials with times the strength of steel and only a fraction of the weight; shrinking all the information at the library of congress into a device the size of a sugar cube; detecting cancerous tumors that are only a few cells in size. some of these research history and technology goals will take or more years to achieve. but that is why—precisely why … there is such a critical role for the federal government.’ a major presidential address now incorporated aspects of the utopian views suggested by drexler and adopted by science managers. returning to washington, dc on air force one, neal lane and nsf director rita colwell reiterated the promise of nano- technology for reporters. according to lane, ‘nanotechnology may not be something that everybody talks about every day, but they will, because it’s really the whole next generation in manufacturing.’ not surprisingly, colwell and lane praised the speech and predicted wide bipartisan support of the president’s plan. in fact, just a few months before clinton’s speech, an editorial in the washington post by former house speaker gingrich claimed nanotechnology would ‘have as big an impact on our lives as transis- tors and chips did in the past years’ and called for a substantial increase in federal support for science. despite the utopian gloss advocates could put on the importance of nanotechnology to national needs, the annual appropriations process grounded the american nano- technology initiative to more prosaic political and budgetary struggles. initial congres- sional response to the nni was positive. at a senate roundtable discussion in april , senator evan bayh, who twenty years earlier co-sponsored the bayh–dole act that helped re-shape the relationship between universities and the federal government, called nanotechnology ‘extremely important to future rates of innovation’ and the overall economy in the usa. he and several of his colleagues heard presentations from richard smalley as well as donald eigler of ibm. improvising on his earlier testi- mony, smalley noted how basic sciences like physics and chemistry were at the core of nanotechnology. a vote for the nni was, in effect, a vote for basic science research and education. as spring arrived in washington, it became clear that the science advocates would not secure funding for the nni without a struggle. concerns over the nni centered around several issues. some republican lawmakers warned that roco’s multi-agency plan would be hard to manage and result in a duplication of research. the nni lacked, one congressman complained, ‘a clear strategy to ensure coordination within the government.’ meanwhile, a non-partisan report from the congressional research service noted that, as ‘nanotechnology was still in its infancy,’ large-scale practical applications were at least a decade away. finally, those lobbying congress to double the entire nsf budget opposed any funding for the nni that came from research programs already established. in may , the senate subcommittee that controlled appropriations for both nasa and the nsf met. senator christopher bond, the panel’s chair, expressed doubts not about the nni’s value per se but about how the nsf would manage the rapid infu- sion of funding. the missouri republican told nsf officials to ‘count me skeptical’ about multi-agency initiatives like the nni and asked the agency to clarify how it would allocate the requested increase in funds for nano-research. bond’s minority counter- part, senator barbara mikulski of maryland, expressed her own worries about allocat- ing monies to the nni without any kind of long-term plan. as she told lane and colwell, nanotechnology seems ‘like our little secret … we need visibility.’ w. p. mccray a few weeks before the senate hearing, nanotechnology did indeed receive greater visibility, although not the kind its advocates wanted. in april , the technology magazine wired published an article by bill joy called ‘why the future doesn’t need us.’ joy, one of the co-founders of sun microsystems, could not be dismissed as a neo-luddite. in warning about future technological dystopias, joy singled out nano- technology—especially the drexlerian visions of autonomous and self-replicating nano-assemblers—as a potential threat to humanity. joy’s article became especially infamous for highlighting the ‘grey goo’ problem, the idea that uncontrolled self-repli- cation by nanomachines might destroy entire ecosystems and threaten what it meant to be human. in contrast to the utopian views of drexler or the more attainable goals roco and other nni supporters proposed, joy, writing as a ‘skeptical nanoist,’ sounded the tocsin for a decidedly dystopian vision of a nano-future and urged a moratorium on further research. nano-advocates recognized the potential danger opponents like joy posed. just as utopian visions can generate public support and shape favorable policy, dystopian ones can derail them. at the may senate hearing, senator bond remarked on the ‘hysteria and fear’ already surrounding genetically modified foods and it was easy for nano-advocates to imagine a similar public reaction to nanotechnology. there is no direct evidence that joy’s concerns influenced congressional debate of the nni in the summer of . furthermore, joy did not represent the dominant view of industry. according to one participant in the establishment of the nni, a ‘critical factor’ in the selling of the nni in the summer of was the vocal support indus- try representatives, especially those in the semi-conductor business, gave on the hill. over the summer of , these lobbying efforts paid off as a swell of bipartisan support for the nni swept away concerns, fiscal, dystopian, or otherwise. maryland’s senator mikulski, renowned in science circles as a staunch advocate of nasa, jumped on the utopian bandwagon. in a speech at nasa headquarters in june , mikulski told her audience that ‘we are on the verge of a new revolution—the nanotechnology revolution’ and urged her colleagues to support the nni, one of the ‘least noted and most important documents of the clinton administration.’ across the senate aisle, republican senator trent lott praised nanotechnology in a letter to his colleagues on the senate appropriations committee. lott hailed the nni not so much for its utopian potential but because the national research infrastructure it would help create might be based in regions like lott’s home state of mississippi, which traditionally received few federal research dollars. at the end of the summer, roco’s committee formally unveiled its proposal for the nni, now honed by months of fine-tuning. the national nanotechnology initiative: the initiative and its implementation plan requested us$ million—us$ million of which the nsf would dispense—to expand research at the nanoscale. at the heart of the interagency plan was an increase of some us$ million for basic research to fund individual scientists and small teams. this was a major increase, up about % from the previous fiscal year to us$ million. while defined as ‘research leading to new fundamental understanding and discoveries,’ the proposal clearly tied this history and technology research to the ‘capacity to create new affordable products with dramatically improved performance.’ the report also identified several ‘grand challenges,’ broad areas of research targeted for interagency funding. these included creating new nanostructured mate- rials, nanoelectronics, and bio-nanosensors and linked basic science and engineering to ambitious, long-term economic goals. congress directed the remaining money to construct a national infrastructure with ‘centers of excellence’ where nano-researcher would work with the stated goal of producing new discoveries to be ‘rapidly commer- cialized by industry.’ after last-minute political wrangling, congress approved budgets for the nni’s various agencies in the fall of . some us$ million of federal money was directed to fund the nni, representing a % increase in the national investment in nanotech- nology compared to the previous year. several states followed suit. california, with % of the us population and the world’s fifth largest economy, has frequently been on the leading edge of new technological developments. in late , then-governor gray davis approved a us$ million state initiative to foster nanotechnology in california: ‘it’s my hope,’ davis explained, ‘to replicate silicon valley.’ the overall funding profile for the national investment in nanotechnology is shown in figure . three important facts stand out. in the span of little more than half a decade, nanotechnology advocates like roco and two different administrations had increased national funding for nanoscale science and engineering by some %. second, the nsf and the department of defense control the largest amounts of nni funding and the relative amounts of money going to civilian versus defense-related research in nano- technology reflect changing national priorities after the september attacks. finally, national enthusiasm for nanotechnology, at least in terms of budget allocations, only increased after george w. bush was selected president in . the new republican administration generously supported nanotechnology, acting in part on the belief that the nascent field would contribute significantly to national security. on december , bush signed the ‘ st century nanotechnology research and development act’ which authorized us$ . billion more for nano-research over the next four years. if one accepts the premise that budgets reflect policy, any doubts about nanotechnology’s place as the first ‘boom science’ of the st century or immediate concerns about envi- ronmental or societal consequences were swept away by the flood of money that began pouring into universities and national laboratories in . nano-boom or gloom? it is too soon to judge the effects the nni may have on society, industry, or the scientific community. indeed, one might even hesitate to call nanotechnology a full-fledged ‘technology’ as so very few of the devices that advocates had envisioned have material- ized. furthermore, nanotechnology has yet to infiltrate public awareness fully, as a recent poll indicated. however, we can try to understand the reasons and rationales that prompted lawmakers to direct vast sums of taxpayer dollars to support a realm of technoscience that retains strong links to fiction as much as facts. w. p. mccray the nni emerged at a salient point in us history. in the late s and throughout the s, economic competitiveness replaced the twilight military struggle of the cold war, and science advocates could no longer claim national defense as the prime ratio- nale for funding basic research. lawmakers were still struggling to adapt national policies to the new global environment and to the implications of the increasing commercialization of science. advocates of the nni proposed it at a propitious time— between the end of the cold war and a renewed preoccupation with national security after september —when lawmakers were trying to reshape national science policy. one recent analysis correctly situates the nni in the period of ‘post-academic’ science. this regime is characterized by an emphasis on the utility of science and the enlistment of academic research as a ‘wealth-creating technoscientific motor for the whole economy,’ views clearly expressed in the documents and testimony supporting the nni. while the end of the cold war is certainly relevant, the changing nature of research funded by the federal government and conducted at universities is even more significant. since the passage of the bayh–dole act in , the ‘triple helix’ of relations between the academy, industry, and government has been significantly altered and strengthened. the borders between science and technology, as the nni implementa- tion plan shows, have blurred while the commercialization of academic science has become a key driver for its funding. the favorable timing of the nni only partly accounts for its success. it cannot explain fully the justifications deployed in support of a major new initiative that would benefit science, technology, and industry. as we have seen, nano-advocates presented an array of heterogeneous arguments to congress and the public. despite the new period of ‘post-academic science,’ many of these justifications were framed in familiar ways. they included the appeal to national competitiveness, introduced in the s in the face of japan’s economic success, and the need for america to ‘plant a flag,’ as did the apollo astronauts, on the cutting edge of a new technology. while american scientists claimed two-thirds of the nobel prize for their discovery of buckyballs, such honors did not ensure that the usa would reap commercial benefits from them. that japan and europe had or were planning major government programs for nano- technology allowed advocates of the nni to argue that it was imperative that the usa do likewise. congressional witnesses predicted that nanotechnology would draw american youth into science, a rationalization for science funding that dates to the sputnik era at least. chemist richard smalley reached back even further in time in his testimony, claiming that nano-research as ‘small science’ was a way for the individual scientist to do more personal research commensurate with the days of sealing wax and string, and after september , national security, the major rationale for so much cold war-era research and development, emerged once again as a major justification for funding nanotechnology. the nni also offered lawmakers and science managers an opportunity to revitalize areas of research they saw as under funded during the s. clinton’s announcement in of major federal support for nanotechnology, for example, was part of a larger history and technology strategy to significantly increase the nsf’s budget and an opportunity for physics, chemistry, and engineering to regain lost ground due to stagnant budgets during the s. the nni, one editorial noted, ‘may prove to be one of the most brilliant coups in the marketing of basic research’ since nixon announced the ‘war on cancer.’ however, while the public could understand the necessity of research on cancer, the nni relied on strategic and utopian marketing to enable its success. indeed, one can question whether the nni is really even science policy per se. after leaving the nsf, neal lane, one of the advocates for the nni inside the white house, admitted that the nni was actually much more a technology policy and those who advocated the applications (as opposed to the fundamental knowledge) enabled by nano-research had won the day. the nni funded the basic research that advocates like smalley called for, but much of this was directed toward specific commercial applications and national goals. finally, one must acknowledge the energy that entrepreneurial science managers like roco invested in crafting a policy and plan for the nni. as roco explained, the nni was ‘prepared with the same rigor as a science project between and : we developed a long-term vision for research and development.’ these efforts succeeded in winning over lawmakers initially skeptical of a complex multi-agency effort as well as the nsf’s ability to manage a major infusion of funds. one can compare the success the nni had with other major research initiatives. opponents of the ill-fated superconducting supercollider, for example, criticized it as a mega-project that would benefit a small and elite research community as well as a single state (texas). in comparison, the nni’s funding was not earmarked for a single project, discipline, or region. many parts of the country would presumably bene- fit from congressional support for the nni and the research monies would benefit a large number of researchers in both the life and physical sciences. in this sense, the organization and funding of the nni was a decentralized form of federally supported big science similar to the human genome project. advocates for both claimed the programs would foster pluralism and decentralization in science as well as local invest- ments and research initiatives. the establishment of national policies for nanotech- nology also resembles the rush to fund research in high-temperature superconductivity in the late s. descriptions of levitating trains, medical breakthroughs, and robust economic competitiveness all spurred federal and commercial investment in funda- mental research conducted with an eye toward future applications from the outset. overshadowing all of these rationales are two meta-reasons, both familiar and suspect to historians of technology, which also help account for the success of the nni. while technological determinism may be out of fashion with scholars, nano-advocates regularly made arguments employing various shades of it. a typical line of reasoning invoked moore’s law (which states that the computing power on a microchip doubles roughly every months) and described the emergence of economic crises once engi- neers reached the physical limits of what was possible with microtechnologies. indeed, industry advocates used the seeming end of the technological improvements described by moore’s law to push for the nni. this depiction of technological inevitability arose from nothing more than what experts claimed was the ‘natural’ w. p. mccray development of computing technology. advocates presented nanotechnology as one way to avert these limitations. indeed, according to some enthusiasts, revolutionary developments at the nanoscale were themselves inevitable, yet another phase in human mastery over nature. even more powerful as a motivating force were predictions of the utopian benefits nanotechnology could bring to american society and the economy. visions of tomor- row that roco, smalley, and others successfully presented—which themselves tapped into richard feynman’s mythic vision of nanotechnology’s potential and the futuristic, sometimes outlandish, ideas put forth by people like drexler—attracted and excited lawmakers. with the end of the cold war and lawmakers’ continued interest in economic competitiveness, nanotechnology offered to reshape, literally, how our world was constructed. as david nye has pointed out, american narratives of techno- logical utopias come in a variety of categories: natural where technologies are a natural outgrowth of society; ameliorative in which new machines improve everyday life; and transformative in which technologies reshape social reality. nanotechnology appears as a hybrid example as advocates drew upon elements from all three narratives in their lobbying efforts. while the most extreme scenarios of a future made better through nanotechnology originated with people like drexler, who operated at the vanguard (and sometimes the fringe) of nanotechnology, they were embraced and repackaged by mainstream science managers and renowned researchers. mihail roco and his colleagues described nanotechnology with an exuberance that matched the prognostications of drexler and his allies. roco promoted the coming convergence of nanotechnology with biotech- nology, information technology, and cognitive science (‘nano–bio–info–cogno’ in policy jargon), which could produce a ‘golden age … an epochal turning point in human history.’ as expressed, ‘if the cognitive scientists can think it, the nano people can build it, the bio people can implement it, and the it people can monitor and control it.’ fully espousing an understanding of history predicated on an unshakable belief in technological progress, the funding of nanotechnology put humanity ‘at the threshold of a new renaissance of science and technology.’ whether this conver- gence is indeed real or whether it represents another phase in the marketing of nano- technology is yet to be seen. visions of a future enabled and ennobled by nanotechnology share many common themes with scenarios presented by advocates of nuclear power, space exploration, and genetics technology. for example, supporters of nuclear power claimed that it would leave practically no part of society unimproved. funded by the federal government and viewed with fear and fascination by the public, advocates presented the power of the nucleus as the solution to a host of economic, social, and national security problems. by eliminating hunger, unemployment, environmental degradation, and the drudgery of housework, nuclear power promised ‘dazzling possibilities of life, liberty and the pursuit of happiness.’ outer space, meanwhile, offered americans new frontiers to explore as well as endless research opportunities for scientists. decades later, advo- cates of genetic engineering assured the possibility of disease prevention and therapy along with an improved understanding of what it meant to be human. supporters of history and technology nanotechnology, deliberately or no, conflated these disparate utopian aspects. nano- technology could ‘offer the opportunity to understand life processes … cure and prevent disease, heal injured bodies, and protect society’ all while providing more ‘endless frontiers’ for exploitation and exploration by scientists and entrepreneurs. dystopian warnings, put forth initially by joy and others, did not abate after the nni was funded. if anything, the surge of new money directed toward nano-research and development fueled anxieties. researchers spoke out publicly on the possible toxicity of newly designed nanoparticles and the insurance industry, still engaged in asbestos-related lawsuits, began to estimate litigation costs stemming from nanotech- nologies. politicians were also aware of a potential backlash against the initiative they had approved. at an april hearing on nanotechnology’s societal effects, vicki l. colvin, director of the center for biological and environmental nanotechnology at rice university, warned congress that nanotechnology needed to avoid the ‘wow-to- yuck’ arc that genetically modified organisms had taken. at the other end of the spectrum, eric drexler, arguably the most well-known and visionary advocate of nanotechnology’s transformative potential, criticized the nni for its timidity and busi- ness-as-usual funding strategy. leaders of the nni, drexler charged, had neglected the original ‘feynman vision’ of nanomachines because ‘public concern regarding its dangers might interfere with research funding.’ despite the ample and growing funding directed toward nanotechnology, debate over the trajectory its research and development would take remained robust and unsettled. in the s, visionaries like henry dreyfuss and norman bel geddes believed that utopia could literally be designed and society thereby perfected. advocates of nano- technology expressed similar views; namely that the future could be crafted atom by atom. whether future generations will look at predictions about nanotechnology’s ability to re-shape the world with the same bemusement that the phrase ‘energy too cheap to meter’ draws remains to be seen. nanotechnology remains as much a futuris- tic vision as an active area of real-life research and development. with the inevitable disappointments that almost always accompany predictions of technological utopias, one may wonder why they remain so attractive to scientists, lawmakers, and the public. as the history of nanotechnology continues to unfold, perhaps historians will address this question again and arrive at a more nuanced and specific answer. until that time, a simpler explanation remains—visions of technological utopias, despite their dubious claims to success and the darker visions that accompany them, still sell and compel. acknowledgements the research for this article was supported by a grant from the california nanosystems institute and national science foundation grant ses (as part of a nanoscale interdisciplinary research team project). several references cited in this article are available in on-line format only. where this is the case, a url link is provided and a hard copy of the document is in the author’s working files. he wishes to acknowledge the assistance and suggestions of nicole archambeau, larry badash, justin bengry, evelyn hu, john krige, kristen shedd, and the anonymous reviewers. w. p. mccray notes [ ] ‘interview with mihail c. roco,’ http://www.nano.gov/html/interviews/mroco.htm. [ ] a second facility is being built at the university of california at los angeles. almost all publi- cations, regardless of audience, tend to use ‘nanoscience’ and ‘nanotechnology’ interchange- ably with a strong preference for the latter and presumably more all-encompassing term. despite the obvious historiographical conundrum this poses for the historian of technology, i have adopted this style except where i am explicitly referring to the actual scientific research on nanoscale phenomena and techniques. [ ] the white house, ‘national nanotechnology initiative.’ [ ] m. c. roco, ‘broader societal issues,’ office of science and technology policy, ‘national nanotechnology initiative.’ [ ] roco, ‘international strategy.’ [ ] roco, ‘towards a us national,’ . [ ] a nanometer (the prefix is the greek word for ‘dwarf’) is one-billionth of a meter and an oft- quoted unit of measurement cited in nanotech literature, the width of a human hair, is some , nanometers wide. [ ] definition adapted from www.nano.gov, the official website for the national nanotechnology initiative. [ ] barber and freestone, ‘an investigation.’ [ ] horst stormer quoted in amato, nanotechnology, . [ ] first quote from john armstrong, formerly chief scientist at ibm, quoted on p. viii of roco et al., nanotechnology research directions;’ second quote from roco, ‘the us national,’ . [ ] atkinson, nanocosm. [ ] see, for example, the papers collected in baird et al., discovering the nanoscale. the issue of patents is presented in meyer, ‘patent citation analysis’ while a view of potential risks is artic- ulated in swiss-re, ‘nanotechnology’ risk perception series. see also crow and sarewitz, ‘nanotechnology and societal transformation;’ fogelberg and glimell, bringing visibility to the invisible. an example of the few articles with a focus on the history of nanotechnology include johnson, ‘the end of pure science?’ which addresses policy issues and mody, ‘from the topografiner’ which discusses instrumentation. [ ] see, for example, kingdon, agendas, alternatives, and public policies as well as papers in sabatier, theories of the policy process. see also korsmo and sfraga, ‘from interwar to cold war’ and cook-deegan, ‘the human genome project’ for examples of how specific research programs were advocated. [ ] mccurdy, space and the american imagination. [ ] sarewitz, ‘does science policy exist?’ [ ] see essays in corn, imagining tomorrow, as well as the more recent collection by sturken et al., technological visions. [ ] feynman, ‘there’s plenty of room at the bottom.’ [ ] ibid., . [ ] feynman’s talk appropriated ideas by science fiction author robert heinlein in his novella waldo and, as colin milburn notes, nanotech’s real origin can be argued to rest not with feynman but in science fiction: milburn, ‘nanotechnology.’ [ ] a search of the world wide web in for the most popular web pages dealing with feynman returned as many references to his paper as they did his nobel prize. also worth noting is the fact that the foresight institute, a non-profit organization devoted to promoting nanotechnology, annually awards a prize named after feynman. [ ] taniguchi, ‘on the basic concept.’ taniguchi’s term, used in a much different fashion from today, described precision machining of devices with tolerances less than a microme- ter. [ ] baird and shew, ‘probing the history.’ history and technology [ ] mody, ‘from the topografiner.’ as mody notes, scientists in the united states gradually adopted the stm in a variety of settings including corporate and national research labs as well as university departments. in , the same year that binnig and rohrer won the nobel prize, digital instruments was founded in santa barbara, california and became the first company to market their version of an stm, the ‘nanoscope.’ [ ] eigler and schweize, ‘positioning single atoms.’ [ ] siebert, ‘the next frontier.’ [ ] mody, ‘from the topografiner.’ [ ] drexler, ‘molecular engineering.’ [ ] ibid., . [ ] drexler, engines of creation. [ ] monmaney, ‘nanomachines to our rescue.’ [ ] amato, ‘the apostle of nanotechnology.’ [ ] stix, ‘waiting for breakthroughs.’ [ ] amato, ‘the apostle of nanotechnology,’ . [ ] science committee on commerce, science, and transportation, ‘new technologies for a sustainable world.’ [ ] ibid., . [ ] ibid., . [ ] corn, ‘epilogue’ and drexler testimony in science committee on commerce, science, and transportation, ‘new technologies for a sustainable world,’ . [ ] du charme, becoming immortal. [ ] jones, ‘technical boundless optimism’ which was a review of regis’s nano!. [ ] stix, ‘waiting for breakthroughs.’ [ ] the permeable boundary between science and science fiction is considered in milburn, ‘nanotechnology.’ moreover, the efforts of scientists to delineate between ‘real’ science and the long-term visions put forth by people by drexler stands as a classic example of boundary work; see, for example, gieryn, cultural boundaries of science. [ ] roco, ‘the us national,’ . [ ] this was funded at about us$ million in , a modest amount by nsf standards. [ ] a note on the funding process: the president’s budget is typically submitted in january each year. in the us, new actions require a two-step congressional process—authorization and appropriation, two interdependent yet distinct activities. the actual allocation of money requires the prior passage of an authorization statute and the authorization process is done by a pair of committees, one in the house and one in the senate. [ ] this was a point made in a number of studies including a report by the council on competi- tiveness called ‘science in the national interest.’ [ ] crawford, ‘japan starts a big push.’ [ ] boesman, ‘analysis of ten selected.’ [ ] office of the press secretary, ‘white house releases.’ [ ] this was originally called the national research for submicron structures; the name was changed in . six years later, the nsf funded the national nanofabrication users network which expanded the cornell model to four other schools. [ ] roco, ‘the us national,’ . [ ] a report from the may workshop was later published; siegel et al., wtec workshop report on r&d status and trends. according to one person involved in the process, some scientists were uncomfortable with the fact that roco appeared to have already decided that the us presence in nanotechnology was not sufficient. evelyn hu, january personal communication with the author. [ ] ibid., . [ ] a follow-up report addressed the specific question of where the us stood in relation to japan and europe; siegel et al., ‘nanostructure science.’ w. p. mccray [ ] house of representatives committee on science, th congress. ‘unlocking our future.’ [ ] gingrich, ‘february , letter.’ [ ] according to the report, the pre-world war two period was the first ‘mega-era’ of science policy while the us support of science and technology for national defense during the cold war typified the second ‘mega-era.’ [ ] the bayh–dole act encouraged the utilization of inventions produced under federal funding and promoted the participation of universities in the commercialization of ideas derived from basic research. [ ] lane’s april testimony can be found on the web site for the house committee on science: http://www.house.gov/science/. [ ] amato, nanotechnology. what is unknown is how effective this campaign was or how many people it reached. [ ] house of representatives committee on science, ‘nanotechnology,’ – . [ ] ibid., . [ ] ibid., . [ ] ibid., . [ ] ibid., . [ ] pres. george h. w. bush established pcast in . it is a non-governmental advisory group formed without congressional approval. therefore, each president must renew the group’s existence. president clinton established his pcast in november by executive order. [ ] this and subsequent quotes from the pcast review; pcast’s review available at: http:// www.ostp.gov/pcast/pcastnano .html. [ ] december : http://www.ostp.gov/pcast/pcastnano.html. [ ] william j. clinton; january speech. text available at: http://pr.caltech.edu/events/ presidential_speech/pspeechtxt.html. [ ] lane quote from jones, ‘aboard air force one.’ [ ] jones, ‘former house speaker gingrich.’ [ ] leath, ‘administration and congress.’ [ ] leath, ‘senate science and technology caucus.’ [ ] southwick, ‘nanotechnology.’ [ ] davey, ‘manipulating molecules.’ [ ] leath, ‘nsf hearing.’ [ ] joy, ‘why the future doesn’t need us.’ [ ] with apologies to robert boyle and his book the sceptical chymist. [ ] for example, the popular science fiction show star trek: voyager featured a main character who could assimilate other life forms by injecting them with ‘nano-probes.’ [ ] joy’s article did encourage policy makers to stress the need to better understand (i.e., fund studies of) the environmental and societal risks of the nano-frontier. the article was also seen as a sufficient threat so as to warrant a response from john s. brown, a researcher at xerox parc at a september conference the nsf convened to address the ethical and societal issues of nanotechnology; see brown, ‘don’t count society out.’ glimell, ‘grand visions and lilliput politics’ discusses joy’s article and roco’s reaction—what glimell calls ‘doing the “roco”-motion’—to it. [ ] evelyn hu, january personal communication with the author. more work clearly needs to be done to understand the complexities of the support industry provided to the nni. [ ] quote from p. of roco and bainbridge, societal implications. mikulski’s support of science, and nasa in particular, is detailed in munson, the cardinals of capitol hill, which provides an insightful look at the appropriations process. [ ] roco and bainbridge, societal implications, . [ ] national science and technology council, ‘national nanotechnology initiative.’ this was submitted by the subcommittee on nanoscale science. engineering, and technology (nset), chaired by roco, which replaced the earlier iwgn. history and technology [ ] national science and technology council, ‘national nanotechnology initiative,’ . [ ] the ‘grand challenges’ areas were to receive a total of some us$ million, $ million more than the previous year. some of this was to administered by the nsf but the depart- ment of defense was slated to be the single largest recipient of ‘grand challenge’ funds. [ ] some us$ million (about % of the nni funding) was set also aside for workforce training and studying societal and ethical implications. national science and technology council, ‘national nanotechnology initiative,’ . [ ] of this, the nsf received us$ million; the department of defense us$ million. [ ] markoff, ‘california sets up centers.’ [ ] the effects of the terrorist attacks of september on funding for nanotechnology is complex and cannot be more than noted here. an august letter from john h. marburger, pres. bush’s science advisor noted that nanotechnology was ‘essential to achieving the president’s top three priorities: winning the war on terrorism, securing the homeland, and strengthening the economy;’ included in national science and technology council, ‘national nanotechnology initiative: research and development’ (supplement to the president’s fy budget). [ ] us$ million was requested for fiscal year alone. [ ] sarewitz, ‘does science policy exist,’ notes the relation, for better or worse, between budgets and policy in the usa. [ ] fewer than % of people polled had heard of ‘nanotechnology’ and less than % could offer a reasonable definition of it. the royal society, nanoscience and nanotechnologies,’ . [ ] johnson, ‘the end of pure science?’ while the term post-academic science’ is itself from ziman, real science. [ ] ziman, real science, . [ ] the literature on this phenomenon is vast; a classic paper on the topic is etzkowitz, ‘entrepre- neurial science in the academy.’ [ ] for example, for fiscal year the bush administration added another ‘grand challenge’ to the nni which would focus on homeland security via detection and protection against chemical, biological, explosive, and radiological (cber) threats. [ ] editors, ‘megabucks for nanotech.’ [ ] baird and shew, ‘probing the history,’ . [ ] the focus on applications is clear in congressional debates over science budgets. as jones, ‘house appropriations bill’ notes, discussion of the fiscal budget referring to nanotech- nology specifically asks the nsf to increase research support for practical applications such as improving semiconductor devices. [ ] roco, ‘the us national,’ . [ ] riordan, ‘the demise.’ [ ] heilbron and kevles offer a comparison between the ssc and the human genome project in ‘finding a policy; also cook-deegan, ‘the human genome project.’ [ ] nowotny and felt, after the breakthrough. [ ] roco et al., nanotechnology research directions, x. [ ] evelyn hu, january personal communication with the author. [ ] roco, ‘the us national,’ . [ ] for example, an article by drexler’s wife and partner at the foresight institute draws a direct line from the greek concept of the atom to the future benefits of nanotechnology, suggesting the inevitability of this path; peterson, ‘nanotechnology.’ [ ] nye, ‘technological prediction,’ . [ ] roco, ‘coherence and divergence;’ roco and bainbridge, ‘converging technologies.’ [ ] quotes from roco and bainbridge, ‘converging technologies,’ and . [ ] roco and bainbridge, ‘converging technologies;’ . w. p. mccray [ ] according to evelyn hu, roco’s emphasis on nano’s convergence with others areas of research may be part of a ‘deliberate repackaging’ of the nni to ensure that interest and fund- ing remain strong. evelyn hu, january personal communication with the author. [ ] del sesto, ‘wasn’t the future,’ . [ ] mccurdy, space and the american imagination. [ ] committee for the review of the national nanotechnology initiative, small wonders, endless frontiers. [ ] the publication of michael crichton’s bestselling potboiler prey, the plot of which centers around hostile swarms of nanomachines, undoubtedly tarnished the limited public perception of nanotechnology as well. [ ] monastersky, ‘the dark side of small;’ swiss-re, ‘nanotechnology.’ [ ] house of representatives committee on science, ‘societal implications of nanotechnology,’ . [ ] drexler, ‘nanotechnology.’ [ ] seagal, technological utopianism. references amato, ivan. ‘the apostle of nanotechnology.’ science , no. 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group. the lancet infectious diseases vol january http://infection.thelancet.com reflection & reaction concomitant bilateral herpes zoster ophthalmicus hassan pervez and colleagues present a clinical picture purporting to show concomitant bilateral herpes zoster opthalmicus without providing conclusive evidence of the diagnosis. in the tzanck test, the presence of giant epithelial cells and multi- nucleated giant cells in stained material from the base of vesicular lesions is taken to indicate the presence of alpha herpes viruses, but does not identify the causative agent. antigen detection, nucleic acid testing, or viral culture of the material is needed to establish whether herpes simplex virus , , or varicella zoster virus is responsible. laboratory diagnosis is of particular relevance in this case given the bilateral distribution of the rash (and the possible absence of associated pain and eye involvement). identification of the specific virus responsible is not an academic exercise. herpes simplex virus and varicella zoster virus warrant very different dosages of antiviral medications and vary in their prognostic significance, especially in the elderly patient. eithne m e macmahon emm is consultant and honorary senior lecturer at the virology section, department of infection, guy’s and st thomas’ hospital, london, uk correspondence: dr eithne macmahon virology section, department of infection, guy’s and st thomas’ hospital, st thomas’ hospital, th floor, north wing, lambeth palace road, london se eh, uk. tel + ; fax + ; email eithne.macmahon@gstt.sthames.nhs.uk reference pervez h, potti a, mehdi sa. concomitant bilateral herpes zoster opthalmicus. lancet infect dis ; : . beauty and the beast the recent violence in nigeria around the miss world pageant highlights the growing malaise and discontent of a population that has suffered years of poverty and neglect. despite the considerable wealth that has entered nigeria since the discovery of oil in the southern regions, years of corruption and mismanagement mean that the general population has yet to see any benefit. nowhere is this more poignant than within the health-care sector, where nigeria sees some of the worst statistics in the developing world despite a clear capacity to respond. we spent several months last year as part of a team that responded to a large-scale measles epidemic in kano city, in the north of the country. epidemics of this nature persist in nigeria despite resources and the availability of cheap affordable vaccines, and this was one of the worst measles epidemics in which médecins sans frontières (msf) had intervened. the outpatient departments of two hospitals in which we worked during the intervention saw more than measles cases, from an estimated cases in kano city alone. despite medical care, the case-fatality rate among admissions was as high as %. epidemics of disease are highly politicised in nigeria and in kano state they are frequently covered up by officials. for this reason, msf was not allowed to intervene with free drugs and medical care until the situation became desperate. large- scale epidemics with high case-fatality rates occur with alarming regularity in nigeria. there are a number of reasons for this. first, in the northern regions the routine immunisation system barely functions. of nine districts in kano state, only one has a functioning cold store—the others lack functional refrigerators needed to ensure the cold chain, have inter- mittent electricity supplies, and provide little or no training among health-care professionals as to how to protect vaccines from losing potency. there is no consistent vaccine supply into the country; as a result, measles vaccine-coverage rates are estimated at between % and %, and efficacy rates between % and %. second, as is the case in much of sub-saharan africa, the surveillance systems in place to ensure timely responses to epidemics are poor. substantial delay in the initiation of emergency vaccination and social mobilisation was certainly a contributing factor to development of complications and death among children presenting to the hospital. finally, there are traditional and religious issues, unique to this region, that affect treatment-seeking behaviour. one study reported that only % of mothers had taken their children to formal health facilities when they developed measles. instead, they administer local concoctions to bring out the rash, keep the child wrapped up, and do not feed them. malnutrition was a prevailing factor among many of the children, even in the absence of food shortages within the region. preventable measles- related deaths are estimated to occur every year in nigeria. although in unicef declared a victory in its goal of immunising % of vulnerable populations worldwide, this has for many countries been unsustainable in the face of war, internal conflict, the hiv/aids pandemic, and waning interest from international donors. nowhere is this more poignant than within nigeria, a country that clearly has the wealth and capacity to vaccinate its population with cheap affordable vaccinations. helen cox and siobhan isles hc and si are with médecins sans frontières, ganges street, maitama, abuja, nigeria correspondence: helen cox. fax + ; email helenscox@yahoo.com.au references hargreaves s. time to right the wrongs: improving basic health care in nigeria. lancet ; : – . cox h. assessment of immunisation services in kano, nigeria. amsterdam: msf, . ambe jp, omotara ba, mandu baba m. perceptions, beliefs and practices of mothers in sub-urban and rural areas towards measles and measles vaccination in northern nigeria. trop doct ; : – . miller m. introduction to a novel model to estimate national and global measles disease burden. int j infect dis ; : – . beauty and the beast references science china physics, mechanics & astronomy © science china press and springer-verlag berlin heidelberg phys.scichina.com www.springerlink.com *corresponding author (email: zhengqs@tsinghua.edu.cn) †recommended by hong youshi • research paper • december vol. no. : – doi: . /s - - - small is beautiful, and dry† zheng quanshui , *, lv cunjing , hao pengfei & sheridan john department of engineering mechanics, tsinghua university, beijing , china; department of mechanical and aerospace engineering, monash university, vic , australia received june , , accepted july , thousands of plant and animal species have been observed to have superhydrophobic surfaces that lead to various novel be- haviors. these observations have inspired attempts to create artificial superhydrophobic surfaces, given that such surfaces have multitudinous applications. superhydrophobicity is an enhanced effect of surface roughness and there are known relationships that correlate surface roughness and superhydrophobicity, based on the underlying physics. however, while these examples demonstrate the level of roughness they tell us little about the independence of this effect in terms of its scale. thus, they are not capable of explaining why such naturally occurring surfaces commonly have micron-submicron sizes. here we report on the discovery of a new relation, its physical basis and its experimental verification. the results reveal that scaling-down roughness into the micro-submicron range is a unique and elegant strategy to not only achieve superhydrophobicity but also to increase its stability against environmental disturbances. this new relation takes into account the previously overlooked but key fact that the accumulated line energy arising from the numerous solid-water-air intersections that can be distributed over the apparent contact area, when air packets are trapped at small scales on the surface, can dramatically increase as the rough- ness scale shrinks. this term can in fact become the dominant contributor to the surface energy and so becomes crucial for ac- complishing superhydrophobicity. these findings guide fabrication of stable super water-repellant surfaces. scale effect, line tension, wetting, contact angle, superhydrophobic pacs: . .np, . .dr, . .bc, . .cd, . .la wetting on a rough substrate is considered to be either in the wenzel [ ] or cassie-baxter state [ ]. in the former, the liquid follows the surface corrugations, as shown in figure (a); in the latter the water drop is attached to the surface but in a position on top of the corrugations, which allows air pockets to be trapped under it, as shown in figure (b). usually, only one of these states is stable while the other is metastable [ – ], depending on both the surface chemistry and roughness. it is well known that wetting in the cassie-baxter, rather than wenzel, state is energetically favorable if the hydrophobic surface is sufficiently rough [ – ] and this is generally considered to be a requirement for achieving superhydrophobicity [ ]. in both states, mini- mizing the system free energy can yield apparent contact angles, θ*, that are functions of the intrinsic or chemical contact angle θ (measured on flat solids) and the topography of the roughness structure. chemically modifying the sur- face alone can typically lead to intrinsic contact angles of up to °, but not more [ , ]. the relation between the ap- parent and intrinsic contact angles in the wenzel state is given by cosθ* = rcosθ. the parameter r is the ratio of the wet surface area to its projection or apparent area. in the cassie-baxter state, the classical form of the relationship is given by cosθ* = − + ( +cosθ)f, where f is the area fraction of the wet part of the solid. the wenzel and cassie-baxter relations, apart from some generalizations (concerning, for example, line-tension effects on nanometer-sized drops or more complex roughness topography), have classically been used to characterize the apparent contact angles with zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure wetting on pillar-structured surfaces: (a) wenzel state, (b) cassie-baxter state, (c) the top view of the cassie-baxter state with numerous tri- ple-phase lines (red) distributed over the apparent solid-water contact area, and (d) typical scanning electron microscope images of lithographic fabricated pillar-surface samples with square- and x-shaped pillar cross-sections. remarkable success [ ]. they also tell us that θ* approa- ches ° as the area fraction f decreases or, equivalently, the roughness ratio r increases. recently, however, a num- ber of exceptions have been observed that seem to be at odds with this understanding. for instance, in some very significant experiments [ – ], topographical shapes and sizes of roughness were shown to have a remarkable influ- ence on advancing and receding contact angles. debate on the physical basis of these results has been active but is un- resolved to date. in the cassie-baxter state, there can clearly be numerous triple-phase (solid-liquid-gas) intersection lines that coexist with the trapped air pockets, as schematically illustrated by the red lines in figure (c). it is somewhat surprising that all known contact angle relations overlook the key fact that the total length, lt, of the triple-phase intersection lines per unit of apparent contact surface area can become extremely large as the roughness scale shrinks into the micron-submicron range. here we seek to include this effect in a new relation- ship for wetting applicable to surfaces with micron-submi- cron scale features. to formulate a precise relationship, we require a set of rough surfaces that can both be well-chara- cterized and varied in the parameters that affect the contact angle. to obtain this, without losing the physical basis of the formulation, we consider the periodic pillar-structured surfaces shown in figure . using such surfaces, one can immediately characterize the triple-phase line length as lt = fs− , where f is the area fraction and s = a/l is a shape-de- pendent roughness scale, given by the boundary length l and area a of the pillar cross-sections. for the studied square and x-shaped cross-sections as illustrated in figure , s is equal to a/ and a/ respectively, where a is the side length of either shape. one can get even smaller s by using more complicated or even multiconnected shapes. for a square pillar structure with pillar side length a = μm and the pillar to pillar spacing b = μm, the total triple-phase line length lt per unit square meter is, amazingly, km! this result illustrates the potential for the accumulated total line energy ltλ to become significant as the roughness scale shrinks into the micron-submicron range, given that for various triple-phase combinations, the measured tri- ple-phase line tensions λ are typically on the orders of mag- nitude − – − n [ ]. attaching water to the pillar-structured substrate will change the system free energy per unit apparent area from sgfσ γ+ to sl( ) ,f f fsσ γ λ −− + + where σ (~ . n/m) is the water surface tension, and γsg and γsl are the solid-gas (air) and solid-liquid (water) interfacial energies. thus, the energy (e) released by this process of attachment is equal to cr( cos )( ) ,e l s fθ σ −= + − where the young’s relation sg slcos ( )θ γ γ σ= − has been used, and cr sg sl( cos ) λ λ θ σ σ γ γ = = + + − l ( ) is an intrinsic or chemical length. through a similar deriva- tion to that for the cassie-baxter relation, one obtains * crcos ( cos ) .θ θ ⎛ ⎞ = − + + −⎜ ⎟ ⎝ ⎠ l f s ( ) compared with the cassie-baxter relation, ( ) weights the zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. term that modifies the intrinsic contact angle by a new fac- tor ( − lcr/s), which plays a similar role to the area fraction f in determining the apparent contact angle. it is apparent that this factor becomes increasingly important as we scale down the surface roughness. this new result and its under- lying mechanism provide significant new insights into how to achieve superhydrophobicity by shrinking the roughness scale (s). to validate these findings, we first fabricated three sets of pillar-structured surface samples of size cm× cm on a silicon wafer using photolithography (see figures (c) and (d), or appendix). samples in sets i and ii are square- shaped with fixed f ≈ . and . , respectively, and those in set iii are x-shaped with fixed f ≈ . . in contrast to f being constant, the pillar sizes s were designed to be vari- able. all had their surfaces become hydrophobic by grafting a self-assembled monolayer of octadecyltrichlorosilane (ots, c h cl si, %) onto the samples. we used de-ionized water as the liquid, formed into droplets of μl (spherical diameter . mm). the contact angles were measured using a commercial goniometer (ocah , dataphysics). for flat ots coated surfaces, the contact an- gle was measured to be θ = °± °. the measured contact angles for these structured surfaces are plotted as solid symbols in the graph shown in figure ; they progressively diverge from the values predicted by the cassie-baxter rela- tion (the horizontal dashed lines) as the pillar sizes shrink. the red and blue solid lines are the least-square fits of the measured values to the relation given by ( ) with the single unknown parameter lcr. the relationship’s excellent fit to the data with the single fit parameter lcr = . μm across all the scales confirms that, compared to the cassie-baxter relationship, the new model captures important physical effects of great consequence at small scales. to test the ex- treme case s≈lcr, additional samples were fabricated using photolithography. the obtained pillar structures have s val- ues ranging from . to . μm, but there are irregular cross-sections due to the fabricated sizes being close to the photolithography limit (see appendix). the solid triangle symbols in figure show the measured contact angles, which are all larger than °. the different roughness shapes and area fractions used in these experiments and the measured very high apparent contact angles further confirm the validity of ( ) and its ability to predict contact angles when the surface features are in the micron-submicron range. to exclude the possibility that the increased contact an- gles arose as a result of finer surface roughness on the pillar tops, perhaps as a result of the photolithography, we exam- ined these using an atomic force microscope. they were observed to be as smooth (with fluctuations on the scale of several angstroms, see appendix) as the un-etched silicon wafers, thus confirming that this was not the cause of the large contact angles at small scales seen in the experiments. the experimental observations in figure show the ten- dency of θ* to approach ° as s trends downwards toward figure the roughness size dependence of measured contact angles (solid dots) and the least-square fitted curves (solid lines) based on the new relation ( ). the data are classified into three sets according to the approximately same area fractions and shapes: red circles and blue diamond solid dots for f ≈ . and f ≈ . with square-shaped cross-section, and blue crosses for f ≈ . with x-shaped ones. the horizontal dashed lines in red and blue give the respec- tive cassie-baxter predictions. the fitted value of lcr for all studied samples in the above three sets is equal to . μm. the triangle symbols are for four samples with s near lcr. the insert shows the measured contact angles, with their respective area fractions, for eight pillar-structured samples with s near or smaller than lcr. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. lcr. also apparent from the figure is how well the new rela- tion ( ) predicts the contact angle. as s further decreases across the critical value, lcr, the relation for the energy re- lease (e) reveals that e resulted from the attachment passing through a transition from positive to negative. negative e means that attaching water drops onto such rough substrates would be energetically unfavorable compared to their free state in air. as a consequence, the contact angles with s ≤ lcr would always take the extreme value of °, regardless of the area fraction. to test this, we fabricated four square- or x-shaped pillar-structured samples (figure (a)) with s ranging from . to . μm using an e-beam technique and made it hydrophobic again by grafting an ots. the measured values of θ* are plotted as solid symbols in the insert of figure . surprisingly, the contact angles for sam- ples with relatively high area fractions are significantly lower than °. a possible explanation for this observation may come from the existence of “long-range” hydrophobic interactions that can pull a hung water drop at a distance from tens to hundreds of nanometers to suddenly adhere to the substrate [ – ]. these “long-range” interaction forces come into effect for pillar structures with pillar separations within the submicron range, and make ideal contact angles of ° impossible. to explain this point, we note that the separation between the water surface and the top of an ad- jacent pillar to the contacted one is * sin ( )b b rθΔ ≈ + *( sin ),θ+ where r is the drop radius (figure (b)). for example, for a fabricated sample with b = nm, f = . and s = . μm (insert of figure and appendix), Δ will be less than the hydrophobic interaction range lint, say nm, unless θ* < °. on the other hand, to achieve the extremum contact angle θ* ≈ °, for a water droplet of μl ( . mm in radius) with lint = nm requires a very large separation of int . mb rl> ≈ μ . therefore, the existence of a submicron hydrophobic interaction range lint sets a lower bound on s for the validity of the scaled-down superhydrophobic mechanism. there are over species of water-walking arthropods (insects and spiders) [ , – ] that support themselves on their superhydrophobic cuticles. to survive environmental disturbances such as the impact of heavy rain they have to maintain a cassie-baxter state. based on the analysis pre- sented here, it is clear how fine-scale roughness can produce a uniquely well-suited surface that allows arthropods to maintain stable superhydrophobicity. for pillar-structured surfaces, it is known that the maximum water pressure sus- tainable by the surface to prevent the transition from the cassie-baxter to the wenzel state due to the pillars piercing the water is [ ]: max cos . f p f s σ θ= − − ( ) this clearly shows the trade off between the impact of the scale of the roughness versus the effect of the wet area fac- tion. these act in opposition to each other in determining the maximum pressure that can be withstood to maintain the cassie-baxter state, which is generally required for wa- ter-repellency [ ]. on the one hand, reducing f results in superhydrophobic surfaces, but this is accompanied by a reduced capacity to withstand the pressure of the liquid; on the other hand, reducing the scale of the roughness yields not only a larger contact angle but also better superhydro- phobicity. the above analyses provide the basis to deter- mine the finest submicron scale of naturally occurring su- perhydrophobic surfaces. it also reveals how such surfaces remain superhydrophobic even in potentially destructive environments, such as the impact of heavy rain, where the impacting pressures can be pa or greater. furthermore, it is generally known that higher pillars make the cassie- figure wetting on pillar-structured surfaces with submicron sizes. (a) sem images of four samples with s smaller than lcr made from electron beam lithography, and (b) separation Δ between the water surface and the adjacent non-wet pillar top. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. baxter state more stable. the shortest pillar height h that renders the cassie-baxter state stable while the wenzel one is metastable can be obtained by using the same approach as outlined in ref. [ ], which gives r cr cos . cos c f h l s f θ θ ⎛ ⎞− + = +⎜ ⎟ −⎝ ⎠ ( ) here, amazingly, the reduction in scale again plays a posi- tive role – lowering the minimum pillar height needed to maintain the cassie-baxter state. by contrast, a smaller f pays a higher cost for generating a larger h. furthermore, increasing h alone makes the pillar structure worse not only from the perspective of bending [ ] but also in terms of its susceptibility to the euler instability [ , ]. the effects of roughness scaling down to some dynamic wetting behaviors were also investigated. we report here two particularly interesting observations. for free falling small water droplets ( . μl) released from rest, we ob- served similar bouncing behavior from our scaled-down generated superhydrophobic surfaces to that from traditional small f generated ones [ ]. we show in figures (a) and (b) the observation that both the first bouncing heights and the total number of bounces increase while reducing the rough- ness scale for the square pillar-structured surfaces with the same area fraction f ≈ . . figure (c) shows the represen- tative sem images of pillars from a pillar-structured surface we made with the constant area fraction f = . and gradi- ent pillar sizes. as we vibrate this gradient surface, which is placed horizontally, water drops on the surface move to- ward the area with larger scales (figure (d)). all these ob- servations can be well explained as consequences of enlarg- ing the contact angle effect by scaling down the roughness [ ], thus giving additional support to the new model ( ). j. willard gibbs first articulated the concept of line ten- sion, providing it with a unique thermodynamic conceptual framework. however, there have been ongoing problems with the measurement of line tension. reported values are unacceptably diverse, with, in some cases [ ], order of magnitude differences being reported. this is explained by the small magnitudes of the quantities involved but, as physical effects at small scales come under further scrutiny, the impact of line tension will become increasingly impor- tant. to not have accurate values will be embarrassing to say the least. the new relationship presented in this paper ( ) can be used to precisely determine line tension of solid-liquid pairs. without this explanation of experimental observations based on mechanisms involving line tension, this area of research will remain only qualitative. in this regard, previous important observations of the influence of roughness size on contact angles [ – ] were unable to provide the physical understanding given here. previously proposed models that included the effect of line tension on contact angles for rough substrates only considered line tension effects at the macro-scale in terms of drop dimen- sions, i.e. at the edges of the droplet’s contact line with the solid surface [ ]. since these models omit the much larger contribution of line energy arising from the apparent contact area, as discussed here, their results do not capture all of the physics involved and so cannot capture the large impact of scale on the wetting angle. to conclude, scaling down the roughness into the mi- cro-submicron range is a unique and elegant strategy to achieve not only superhydrophobicity, but also to increase its stability against environmental disturbances. our new model ( ) captures important physical effects of great con- figure the effects of roughness scaling down with fixed f ≈ . on dynamic wetting behavior. (a) images showing water drops bouncing with time; (b) the bouncing heights versus scale s, the red triangle, blue square and green circle symbols correspond to the first, second and third bounces, respectively; (c) sem images of the typical pillars on the pillar-structured surface with f ≈ . and gradient pillar sizes; (d) selected frames at different times of a video re- cording of directional horizontal rolling on the horizontally placed gradient surface that vibrates (see appendix). zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. sequence at small scales. the above results help us to un- derstand why naturally occurring superhydrophobic sur- faces commonly have micron-submicron roughness [ , , , , ] and guide the fabrication of stable super wa- ter-repellant surfaces [ , – ]. as also revealed, the roughness scale is reduced as the maximal contact angle of the roughness scale approaches a fundamental critical length. further reduction of scale sees the contact angle again drop, probably as a result of entering a new dynamic regime in which new forces play a role. this presents an intriguing insight into nature’s selection of optimal resis- tance to wetting, with further research needed to fully un- derstand the transition across the critical length scale. appendix a sample surfaces and measured contact angles a sample preparation a total of superhydrophobic surface samples were fabri- cated based on silicon wafers with micro-pillars ( samples) by photolithography and submicro-pillars (four samples) using e-beam lithography which were coated with octade- cyltrichlorosilane (ots, c h cl si, %). a contact angle measurement the droplets were deionized water, and their volumes were fixed to be μl. the experiments were carried out at room temperature. the contact angles (cas) were measured by using a goniometer (ocah , dataphysics, germany). a summary of results the dimensions and sem (fei, quanta f) image of each of these samples and the typical observed water drop- lets and measured contact angles are summarized below. a . intrinsic contact angle θ the intrinsic contact angle measured on a flat surface with the ots coating is °± °, as illustrated in figure a . figure a a droplet on a flat surface, with the measured contact angle = °± °. a . sizes and contact angles for six square samples designed with f= . table a the first set of six surface samples that have the same designed areas f= . and pillar heights h ≈ μm and their measured geometric pa- rameters and contact angles (cas) θ* designed measured no. a (μm) b (μm) f s (μm) a (μm) b (μm) f s (μm) θ* . . . . . . . °± ° . . . . . °± ° . . . . . °± ° . . . . . . °± ° . . . . . °± ° . . . . . . . °± ° figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ* = . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. a . sizes and contact angles for five square samples designed with f= . table a the second set of five surface samples that have the same designed areas f= . and pillar heights h ≈ μm and their measured geometric parameters and contact angles (cas) θ* original design measured no a (μm) b (μm) f s (μm) a (μm) b (μm) f s (μm) θ* . . . . . . . . °± ° . . . . . . °± ° . . . . . . °± ° . . . . . °± ° . . . . . . . °± ° figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. a . sizes and contact angles for six x-shaped samples designed with f= . table a the third set of six surface samples that have the same designed areas f= . and pillar heights h ≈ μm and their measured geometric pa- rameters and contact angles (cas) θ* original design measured no a (μm) b (μm) f s (μm) a (μm) b (μm) f s (μm) θ* . . . . . °± ° . . . . . °± ° . . . . . °± ° . . . . . °± ° . . . . . °± ° . . . . . . °± ° figure a view of the designed geometrical parameters of the x-shaped micro-pillars. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. a . sizes, shapes and contact angles for four finer samples with s near the critical length lcr table a the fourth set of four surface samples with pillar heights h ≈ μm and their measured geometric parameters and contact angles θ* measured no. f s (μm) θ* . . . °± ° . . . °± ° . . . °± ° . . . °± ° figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. a . sizes, shapes and contact angles for four e-beam fabricated samples with s smaller than the critical length lcr table a the samples with pillar heights h ≈ μm and their measured geometric parameters and contact angles θ* original design measured no. a (μm) b (μm) f s (μm) a (μm) b (μm) f s (μm) θ* . . . . . . . . . °± ° . . . . . . . . . °± ° . . . . . . . . . °± ° zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. table a the samples with pillar heights h ≈ μm and their measured geometric parameters and contact angles (cas) θ* original design measured no. a (μm) b (μm) f s (μm) a (μm) b (μm) f s (μm) θ* . . . . . . . . . °± ° figure a sem images of sample no. in table a and the droplet with measured θ*= . °± °. zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. a . the smoothness of the top surfaces of pillars to exclude the possibility that the increased contact angles arose as a result of finer surface roughness on the pillar tops, we examined these using an atomic force microscope. they were observed to be as smooth (with fluctuations on the scale of several angstroms, figure s ) as the un-etched silicon wafer, thus confirming that this was not the cause of the large contact angles at small scales seen in the experiments. figure a afm (spa- ) of the micro-substrates; the pictures were obtained from the top of one of the micro-pillars, ra= . Å, rms= . Å. appendix b gradient micro-structured substrates figure b illustrative sketch of the designed gradient structured substrate; the total length l of the seven-area sample is . cm and the width w is . cm. table b geometric parameters of the micro-pillars in the gradient structured substrates original design measured no. a (μm) b (μm) f s (μm) a (μm) b (μm) f s (μm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . zheng quanshui, et al. sci china phys mech astron december ( ) vol. no. figure b sem images of the gradient structured substrate; (a)−(g) correspond to figure b and table b respectively. we thank profs. li xide, yin yajin, and li qunqing for helpful discus- sions and sample preparation. financial support from the national natu- ral science foundation of china (grant nos. , , , and ) and from the national basic research program of china (grant no. cb ) is gratefully acknowledged. wenzel r n. resistance of solid surfaces to wetting by water. ind eng chem, , : – 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oxford: blackwell science, aussillous p, quéré d. liquid marbles. nature, , : – lahann j, mitragotri s, tran t-n, et al. a reversibly switching sur- face. science, , : – courbin l, denieul e, dressaire e, et al. imbibition by polygonal spreading on microdecorated surfaces. nat mater, , : – sanchez c, arribart h, guille m m g. biomimetism and bioinspira- tion as tools for the design of innovative materials and systems. nat mater, , : – << /ascii encodepages false /allowtransparency false /autopositionepsfiles true /autorotatepages /none /binding /left /calgrayprofile (gray gamma . ) /calrgbprofile (srgb iec - . ) /calcmykprofile (iso coated v % \ eci\ ) /srgbprofile (srgb iec - . ) /cannotembedfontpolicy /error /compatibilitylevel . /compressobjects /off /compresspages true /convertimagestoindexed true /passthroughjpegimages true /createjdffile false /createjobticket false /defaultrenderingintent /perceptual /detectblends true /detectcurves . /colorconversionstrategy /srgb /dothumbnails 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/monoimageminresolutionpolicy /warning /downsamplemonoimages true /monoimagedownsampletype /bicubic /monoimageresolution /monoimagedepth - /monoimagedownsamplethreshold . /encodemonoimages true /monoimagefilter /ccittfaxencode /monoimagedict << /k - >> /allowpsxobjects false /checkcompliance [ /none ] /pdfx acheck false /pdfx check false /pdfxcompliantpdfonly false /pdfxnotrimboxerror true /pdfxtrimboxtomediaboxoffset [ . . . . ] /pdfxsetbleedboxtomediabox true /pdfxbleedboxtotrimboxoffset [ . . . . ] /pdfxoutputintentprofile (none) /pdfxoutputconditionidentifier () /pdfxoutputcondition () /pdfxregistryname () /pdfxtrapped /false /description << /chs /cht /dan /deu /esp /fra /ita (utilizzare queste impostazioni per creare documenti adobe pdf adatti per visualizzare e stampare documenti aziendali in modo affidabile. i documenti pdf creati possono essere aperti con acrobat e adobe reader . e versioni successive.) /jpn /kor /nld (gebruik deze instellingen om adobe pdf-documenten te maken waarmee zakelijke documenten betrouwbaar kunnen worden weergegeven en afgedrukt. de gemaakte pdf-documenten kunnen worden geopend met acrobat en adobe reader . en hoger.) /nor /ptb /suo /sve /enu >> >> setdistillerparams << /hwresolution [ ] /pagesize [ . . ] >> setpagedevice rna-guided retargeting of sleeping beauty transposition in human cells adrian kovač , csaba miskey , michael menzel , esther grueso , andreas gogol- döring and zoltán ivics ,* transposition and genome engineering, division of medical biotechnology, paul ehrlich institute, langen, germany university of applied sciences, giessen, germany *for correspondence: zoltán ivics paul ehrlich institute paul ehrlich str. - d- langen germany phone: + fax: + email: zoltan.ivics@pei.de keywords: genetic engineering, crispr/cas, gene targeting, dna-binding, gene insertion mailto:zoltan@mdc-berlin.de abstract an ideal tool for gene therapy would enable efficient gene integration at predetermined sites in the human genome. here we demonstrate biased genome-wide integration of the sleeping beauty (sb) transposon by combining it with components of the crispr/cas system. we provide proof-of-concept that it is possible to influence the target site selection of sb by fusing it to a catalytically inactive cas (dcas ) and by providing a single guide rna (sgrna) against the human alu retrotransposon. enrichment of transposon integrations was dependent on the sgrna, and occurred in an asymmetric pattern with a bias towards sites in a relatively narrow, -bp window downstream of the sgrna targets. our data indicate that the targeting mechanism specified by crispr/cas forces integration into genomic regions that are otherwise poor targets for sb transposition. future modifications of this technology may allow the development of methods for specific gene insertion for precision genetic engineering. introduction the ability to add, remove or modify genes enables researchers to investigate genotype- phenotype relationships in biomedical model systems (functional genomics), to exploit genetic engineering in species of agricultural and industrial interest (biotechnology) and to replace malfunctioning genes or to add functional gene sequences to cells in order to correct diseases at the genetic level (gene therapy). one option for the insertion of genetic cargo into genomes is the use of integrating vectors. the most widely used integrating genetic vectors were derived from retroviruses, in particular from γ-retroviruses and lentiviruses ( ). these viruses have the capability of shuttling a transgene into target cells and stably integrating it into the genome, resulting in long-lasting expression. transposons represent another category of integrating vector. in contrast to retroviruses, transposon-based vectors only consist of a transgene flanked by inverted terminal repeats (itrs) and a transposase enzyme, the functional equivalent of the retroviral integrase ( ). for dna transposons, the transposase enzymes excise genetic information flanked by the itrs from the genome or a plasmid and reintegrate it at another position (figure a). thus, transposons can be developed as non-viral gene delivery tools ( ) that are simpler and cheaper to produce, handle and store than retroviral vectors ( ). the absence of viral proteins may also prevent immune reactions that are observed with adeno-associated virus (aav)-based vectors ( , ). the sleeping beauty (sb) transposon is a class ii dna transposon, whose utility has been demonstrated in pre-clinical [reviewed in ( , )] as well as clinical studies [( , ) and reviewed in ( )]. it is active across a wide range of cell types ( , ) and hyperactive variants such as the sb x transposase catalyze gene transfer in human cells with high efficiency ( ). the main drawback of integrating vectors is their unspecific or semi-random integration ( ). for example, lentiviral or γ-retroviral vectors actively target genes or transcriptional start sites ( – ). in contrast, the sb transposon displays a great deal of specificity of insertion at the primary dna sequence level – almost exclusively integrating into ta dinucleotides ( ) – but inserts randomly on a genome-wide scale ( – ). thus, because all of these vectors can potentially integrate their genetic cargo at a vast number of sites in the genome, the interactions between the transgene and the target genome are difficult to predict. for example, the position of a transgene in the genome can have an effect on the expression of the transgene, endogenous genes or both ( – ). especially in therapeutic applications, controlled transgene expression levels are important as low expression levels could fail to produce the desired therapeutic effect, while overexpression might have deleterious effects on the target cell. perhaps more dramatic are the effects transgenes might have on the genome. insertion of transgenes can disrupt genomic regulation, either by direct insertional mutagenesis of cellular genes or regulatory elements, or by upregulation of genes in the vicinity of the integration site. in the worst case, this can result in overexpression of a proto-oncogene or disruption of a tumor suppressor gene; both of these outcomes can result in transformation of the cell and tumor formation in the patient. an alternative technology used in genetic engineering is based on targeted nucleases; the most commonly used nuclease families are zinc finger nucleases (zfns) ( ), transcription activator-like effector-based nucleases (talens) ( ) and the crispr/cas system ( ). all of these enzymes perform two functions: they have a dna-binding domain (dbd) that recognizes a specific target sequence and a nuclease domain that cleaves the target dna once it is bound. while for zfns and talens target specificity is determined by their amino acid sequence, cas nucleases need to be supplied with a single guide rna (sgrna) that determines their target specificity ( ). this makes the crispr/cas system significantly more flexible than other designer nucleases. the introduction of a double-strand break (dsb) in a target cell is usually repaired by the cell’s dna repair machinery, either via non-homologous end-joining (nhej) or homologous recombination (hr) ( , ). the nhej pathway directly fuses the two dna ends together. due to the error-prone nature of this reaction, short insertions or deletions (indels) are often produced. because this in turn often results in a frame-shift in a coding sequence, this process can be used to effectively knock out genes in target cells. if a dna template is provided along with the nuclease, a dsb can also be repaired by the hr pathway. this copies the sequence information from the repair template into the target genome, allowing replacement of endogenous sequences or knock-in of completely new genes ( ). thus, knock-in of exogenous sequences into a genetic locus is a cumulative outcome of dna cleavage by the nuclease and hr by the cell. however, the efficiency of the hr pathway is low compared to the efficiency of the nuclease ( ). this bottleneck means that targeted nucleases are highly efficient at knocking out genes ( , ), but less efficient at inserting dna ( ), particularly when compared to the integrating viral and non-viral vectors mentioned previously. thus, integrating vectors and nuclease-based approaches to genome engineering have overlapping but distinct advantages and applications: nuclease-based approaches are site-specific and efficient at generating knock- outs, while integrating vectors are unspecific but highly efficient at generating knock-ins. based on the features outlined above, it is plausible that the specific advantages of both approaches (designer nucleases and integrating vector systems) could be combined into a single system with the goal of constructing a gene delivery tool, which inserts genetic material into the target cell’s genome with great efficiency and at the same time in a site-specific manner. indeed, by using dbds to tether integrating enzymes (retroviral integrases or transposases) to the desired target, one can combine the efficient, dsb-free insertion of genetic cargo with the target specificity of designer nucleases [reviewed in ( )]. in general, two approaches can be used to direct transposon integrations by using a dbd: direct fusions or adapter proteins ( ). in the direct fusion approach, a fusion protein of a dbd and the transposase is generated to tether the transposase to the target site (figure b, top). however, the overall transposase activity of these fusion proteins is often reduced. alternatively, an adapter protein can be generated by fusing the dbd to a protein domain interacting with the transposase or the transposon (figure b, middle and bottom, respectively). several transposon systems, notably the sb and the piggybac systems have been successfully targeted to a range of exogenous or endogenous loci in the human genome [( – ) and reviewed in ( )]. however, a consistent finding across all targeted transposition studies is that while some bias can be introduced to the vector’s integration profile, the number of targeted integrations is relatively low when compared to the number of untargeted background integrations ( ). in the studies mentioned above, targeting was achieved with dbds including zfs or tales, which target a specific sequence determined by their structure. however, for knock-outs, the crispr/cas system is currently the most widely used technology due to its flexibility in design. a catalytically inactive variant of cas called dcas (‘dead cas ’, containing the mutations d a and h a), has previously been used to target enzymes including transcriptional activators ( – ), repressors ( , ), base editors ( , ) and others ( , ) to specific target sequences. using dcas as a targeting domain for a transposon could combine this great flexibility with the advantages of integrating vectors. by using the hsmar human transposon ( ), a -fold enrichment of transposon insertions into a -bp target region was observed in an in vitro plasmid-to-plasmid assay employing a dcas -hsmar fusion ( ). however, no targeted transposition was detected with this system in bacterial cells. a previous study failed to target the piggybac transposon into the hprt gene with crispr/cas components in human cells, even though some targeting was observed with other dbds ( ). however, in a recent study, some integrations were successfully biased to the ccr locus using a dcas -piggybac fusion ( ). two additional recent studies showed highly specific targeting of bacterial tn -like transposons by an rna-guided mechanism, but only in bacterial cells ( , ). previous studies have established that foreign dbds specifying binding to both single- copy as well as repetitive targets can introduce a bias into sb’s insertion profile, both as direct fusions with the transposase and as fusions to the n targeting domain. n is an n-terminal fragment of the sb transposase encompassing the n-terminal helix-turn-helix domain of the sb transposase with dual dna-binding and protein dimerization functions ( ). fusions of n with the tetracycline repressor (tetr), the e c zinc finger domain ( ), the zf-b zinc finger domain and the dbd of the rep protein of aav were previously shown to direct transposition catalyzed by wild-type sb transposase to genomically located tetracycline operator (teto) sequences, the erbb- gene, endogenous human l retrotransposons and rep-recognition sequences, respectively ( , , ). here, we present proof-of-principle evidence that integrations of the sb transposon system can be biased towards endogenous alu retrotransposons using dcas as a targeting domain in an sgrna-dependent manner. results design and validation of sgrnas targeting single-copy and repetitive sites in the human genome two different targets were chosen for targeting experiments: the hprt gene on the x chromosome and aluy, an abundant (~ elements per human genome) and highly conserved family of alu retrotransposons ( ). four sgrnas were designed to target the hprt gene (figure a), one of them (sghprt- ) binding in exon and three (sghprt- – sghprt- ) in exon . three sgrnas were designed against aluy (figure d), the first two (sgaluy- and sgaluy- ) against the conserved a-box of the pol iii promoter that drives alu transcription and the third (sghprt- ) against the a-rich stretch that separates the two monomers in the full- length alu element. the hprt-specific sgrnas were tested by transfecting human hct cells with a cas expression plasmid and expression plasmids that supply the different hprt-directed sgrnas. disruption of the hprt coding sequence by nhej was measured by selection with - tg, which is lethal to cells in which the hprt gene is intact. thus, the number of -tg-resistant cell colonies obtained in each sample is directly proportional to the extent, to which the hprt coding sequence is mutagenized and functionally inactivated. two sgrnas (sghprt- , sghprt- ) resulted in strong, significant increases in disruption levels (p≤ . ), while sghprt- failed to increase disruption over the background level and sghprt- induced weak but significant disruption (p≤ . ). (figure b). the efficiency of sghprt- was further tested with a tide assay, which provides sequence data from two standard capillary (sanger) sequencing reactions, thereby quantifying editing efficacy in terms of indels in the targeted dna in a cell pool. as measured by tide, sghprt- yielded a total editing efficiency of . % (figure c). the activities of the aluy-directed sgrnas were first analyzed by an in vitro cleavage assay. incubation of human genomic dna (gdna) with purified cas protein and in vitro transcribed sgrnas showed detectable fragmentation of gdna for sgaluy- and sgaluy- (figure e). gdna digested with cas and sgaluy- was purified, cloned into a plasmid vector and the sequences of the plasmid-genomic dna junctions were determined. twelve of sequenced genomic junctions could be mapped to the aluy sequence upstream of the cleavage site and could be mapped to the sequence immediately downstream (as defined by the direction of alu transcription). a consensus sequence generated by aligning the or sequences showed significant similarity to the aluy consensus sequence (figure f), demonstrating that the dna fragmentation was indeed the result of cas -mediated cleavage. the sequence composition also revealed that mismatches within the sgrna binding sequence are tolerated to some extent, while the conserved gg dinucleotide of the ngg pam motif did not show any sequence variation (figure f). in sum, the data establish functional sgrnas against the single-copy hprt locus (by sghprt- ) and against the repetitive aluy sequence (by sgaluy- ). generation of cas fusion constructs and their functional validation three different targeting constructs were generated to test both the direct fusion and the adapter protein approaches described above. for the direct fusion, the entire coding sequence of sb x, a hyperactive version of the sb transposase ( ), was inserted at the c-terminus of the dcas sequence (figure a, top). we only made an n-terminal sb fusion, because c-terminal tagging of the transposase enzyme completely abolishes its activity ( , , ). for adapter proteins, the n domain was inserted at the n-terminus as well as at the c-terminus of dcas (figure a, middle and bottom, respectively). n interacts both with sb transposase molecules and the sb transposon itrs, and could thus potentially use multiple mechanisms for targeting, as outlined in figure b. a flexible linker klgggapavgggpk ( ) that was previously validated in the context of sb transposase fusions to zfs ( ) and to rep ( ) dbds was introduced between dcas and the full-length sb x transposase or the n targeting domain (figure a). all three protein fusions were cloned into an all-in-one expression plasmids that allow co-expression of the dcas -based targeting factors with sgrnas. western blots using an antibody against the sb transposase verified the integrity and the expression of the fusion proteins. (figure b). in order to verify that the dcas -sb x direct fusion retained sufficient transpositional activity we measured its efficiency at integrating a puromycin-marked transposon into hela cells, and compared its activity to the unfused sb x transposase (figure a). we found that the fusion construct dcas -sb x was approximately % as active as unfused sb x. to verify that n retains its dna-binding activity in the context of the dcas fusions, we performed an emsa experiment using a short double-stranded oligonucleotide corresponding to the n binding sequence in the sb transposon (figure b). binding could be detected for the dcas -n fusion, but not for n -dcas . for this reason, the n -dcas construct was excluded from the subsequent experiments. the dna-binding ability of the dcas domain in the fusion constructs was not tested directly. instead, analogous constructs containing catalytically active cas were generated and tested for cleavage activity. the activities of these fusion constructs were determined by measuring the disruption frequency of the hprt gene by selection with -tg, as described above. the cleavage efficiencies of both cas -sb x and cas -n were ~ % of unfused cas in the presence of sghprt- (figure c). because binding of the cas domain to its target dna is a prerequisite for dna cleavage, we infer that cleavage-competent fusion proteins are also able to bind to target dna. collectively, these data establish that our dcas fusion proteins i) are active in binding to the target dna in the presence of sgrna; ii) they retain transposition activity (for the fusion with the full-length sb x transposase); and iii) they can bind to the transposon dna (for the fusion with the c-terminal n targeting domain), which constitute the minimal requirements for targeted transposition in the human genome. rna-guided sleeping beauty transposition in the human genome having established functionality of our multi-component transposon targeting system, we next analyzed the genome-wide patterns of transposon integrations catalyzed by the different constructs. transposition reactions were performed in human hela cells with dcas -sb x or dcas -n + sb x complemented with sgrnas (sghprt- or sgaluy- ) (figure ). as a reference dataset, we generated independent insertions in the presence of sgl - that targets the ’-terminus of human l retrotransposons (figure -figure supplement ). this sgrna was validated for in vitro cleavage by cas , and was found to yield some enrichment of sb insertions within a -bp window downstream of the sgrna binding sites (figure -figure supplement ), although without the power of statistical significance. the sgl - insertion site dataset was nevertheless useful to serve as a negative control obtained with an unrelated sgrna. integration libraries consisting of pcr-amplified transposon-genome junctions were generated and subjected to high-throughput sequencing. recovered reads were aligned to the human genome (hg assembly) to generate lists of insertion sites. in order to quantify the targeting effects, we defined targeting windows of increasing lengths around the sgrna binding sites (figure a). the fraction of overall insertions into each targeting window was calculated (figure b), and these ratios were compared to those obtained with the negative control (same targeting construct with sgl - ) (figure c and d). for the hprt locus, no insertion was recovered within kb in either direction from the sghprt- binding site in our dataset (data not shown). we conclude that either targeting of this single-copy locus was not possible with the current system, or that the number of insertion sites recovered (< insertions) was too low to provide the necessary resolution for detecting an effect. next, integration site datasets generated with dcas -n + sb x + sgaluy- (figure -source data , insertions), dcas -n + sb x + sgl - (figure -source data , insertions) as well as dcas -sb x and sgaluy- (figure -source data , insertions) and dcas -sb x and sgl - (figure -source data , insertions) were compared (figure b). the sgaluy- sgrna has a total of target sites in the human genome (hg ) (the number of sites exceeds the number of aluy elements due to high conservation, and therefore presence in other alu subfamilies). we found some enrichment (ca. %) for dcas -n + sb x in a window of bp around the target sites and dcas - sb x insertions are slightly enriched in a window of bp (ca. %) (figure c), although neither change was statistically significant. to further investigate the distribution of insertions around the target sites, we decreased the size of the targeting windows and counted insertions in up- and downstream windows independently. we only found a modest enrichment with dcas -n , and the pattern seemed to be relatively symmetrical in a window from - bp to + bp with respect to the sgrna binding sites (figure d). however, with dcas -sb x, we found that the enrichment occurred almost exclusively downstream of the target sites, within the aluy element. we detected statistically significant enrichment in the insertion frequencies in a window spanning a -bp region downstream of the sgrna target sites (~ . -fold enrichment, p= . ) (figure d). we also detected enrichment near target loci similar to the target site (with mismatch), although not statistically significant (figure e). this result is in agreement with the finding that the specificity of dcas binding is lower than that of cas cleavage ( ). intriguingly, plotting the overall insertion frequencies around the target sites revealed that the sb insertion machinery generally disfavors loci downstream of the sgaluy- binding sequences (figure a). these results together with the asymmetric pattern of integrations next to the target sites prompted us to investigate properties of the genomic loci around the sgrna target sites. along this line, we next set out to investigate the target nucleotides of the transposons in the targeted segments. to our surprise, we found that the ta dinucleotide frequency in the targeted region is in fact lower than in the neighboring segments (figure b). along these findings, comparison of the nucleotide composition of the targeted vs non-targeted insertion sites revealed that the integrations within the alu sequences are enforced to take place at ta sequences that only weakly match the preferred atatatat consensus palindrome (figure -figure supplement ). thus, targeting occurs into dna that is per se disfavored by the sb transposition machinery. since the nucleotide composition of the targeted regions is remarkably different from that of the neighboring sequences and given that nucleosome positioning in the genome is primarily driven by sequence ( ), we next investigated nucleosome occupancy of the target dna. nucleosome occupancy was predicted in -kb windows on random target sequences and on all the insertion sites of the non-targeted condition (unfused sb x). this analysis recapitulated our previous finding showing that sb disfavors integrating into nucleosomal dna ( ). additionally, in agreement with previous findings of others ( , ), we found that these aluy sequences are conserved regions for nucleosome formation (figure c). these results can explain the overall drop in insertion frequency of sb into these regions. in sum, the data above establish weak, sgrna-dependent enrichment of sb transposon integrations around multicopy genomic target sites in the human genome. discussion we demonstrate in this study that the insertion pattern of the sb transposase can be influenced by fusion to dcas as an rna-guided targeting domain in human cells, and as a result be weakly biased towards sites specified by an sgrna that targets a sequence in the aluy repetitive element. we consider it likely that the observed enrichment of insertions next to sgrna-targeted sites is an underestimate of the true efficiency of transposon targeting in our experiments, because our pcr procedure followed by next generation sequencing and bioinformatic analysis cannot detect independent targeting events that had occurred at the same ta dinucleotide in the human genome. while enrichment observed with dcas -n was very weak and not statistically significant, the enrichment by dcas -sb x was more pronounced, and occurred in a distinctly asymmetric pattern in a relatively narrow window in the vicinity of the sites specified by the sgrna. this observation is consistent with physical docking of the transpositional complex at the targeted sites, and suggests that binding of dcas to its target sequence and integration by the sb transposase occur within a short timeframe. we further detect an asymmetric distribution of insertions around the target sites. asymmetric distributions of targeted insertions have been previously found in a study using the isy transposon (which, like sb, is a member of the tc /mariner transposon superfamily) in combination with the zf domain zif in e. coli ( ) and in experiments with dcas -hsmar fusions in vitro ( ). enrichment mainly occurring downstream of the sgrna target site in our experiments was somewhat surprising, as domains fused to the c-terminus of cas are expected to be localized closer to the ’-end of the target strand ( ), or upstream of the sgrna binding site. the fact that sb x is connected with dcas by a relatively long, flexible linker could explain why enrichment can occur on the other side of the sgrna binding site, but it does not explain why enrichment on the ‘far side’ seems to be more efficient. against expectations, we found that the window, in which the highest enrichment occurs, represents a disfavored target for sb transposition (figure a), likely because it is ta-poor (figure b) – the aluy consensus sequence has a gc content of % ( ) – and nucleosomal (figure c). it is possible that the targeting effect in this window is more pronounced than on the other side of the sgrna target site because there are fewer background insertions obscuring a targeting effect. unlike in our earlier studies establishing biased transposon integration by the n targeting peptide fused to various dbds ( , , ), our dcas -n fusion apparently did only exert a minimal effect on the genome-wide distribution of sb transposon insertions (figure ). because cas -n is active in cleavage (figure c) and dcas -n is active in binding to transposon dna (figure b), this result was somewhat unexpected. we speculate that addition of a large protein (dcas is kda) to the n-terminus of a relatively small polypeptide of amino acids masks its function to some extent. indeed, tetr, the zf-b protein and rep dbd that were used previously with success in conjunction with n are all far smaller than dcas . the binding activity of n to transposon dna, though detectable by emsa, may have been too weak to effectively recruit the components of the sb system to the target site. our data reveal some of the important areas where refined molecular strategies as well as reagents may yield higher targeting efficiencies. first, the difficulty of targeting to a single location, in this case the hprt gene, might be associated with characteristics of the target itself or an indication that the system is not specific enough to target a single-copy site in general. the fact that an integration library consisting of independent sb integrations generated by unfused sb x without any targeting factor also did not contain any integrations within kb of the hprt target sequence either (data not shown) might indicate that the hprt gene is simply a poor target for sb integrations. it should be noted that a previous attempt to target the piggybac transposase to the hprt gene with crispr/cas components also failed, even though targeting with other dbds (zfs and tales) was successful ( ). poor targeting of a single-copy chromosomal region is reminiscent of our previous findings with engineered rep proteins ( ). both rep/sb and rep/n fusions were able to enrich sb transposon integrations in the vicinity of genomic rep binding sites, yet they failed to target integration into the aavs locus, the canonical integration site of aav ( ). thus, selection of an appropriate target site appears to be of paramount importance. the minimal requirements for such sites are accessibility by the transpositional complex and the presence of ta dinucleotides to support sb transposition; in fact, sb was reported to prefer insertion into ta-rich dna in general ( ). the importance of dna composition in the vicinity of targeted sites was also highlighted in the context of targeted piggybac transposition in human cells ( ). namely, biased transposition was only observed with engineered loci that contained numerous ttaa sites (the target site of piggybac transposons) in the flanking regions of a dna sequence bound by a zf protein. an alternative, empirical approach, where careful choice of the targeted chromosomal region may increase targeting efficiencies would be to select sites where clusters of sb insertions (transposition “hot spots”) occur in the absence of a targeting factor. targeting might be more efficient at these sites, because they are by definition receptive to sb insertions. collectively, these considerations should assist in the design of target-selected gene insertion systems with enhanced efficiency and specificity. the results presented here, as well as the results of previous targeting studies ( , , ), indicate that the main obstacle to targeted transposition is the low ratio of targeted to non-targeted insertions. this is likely due to the fact that, in contrast to site-specific nucleases where sequence-specific dna cleavage is dependent on heterodimerization of foki endonuclease domain monomers ( ), or to cas , where dna cleavage is dependent on a conformational change induced by dna binding ( ), the transposition reaction is not dependent on site-specific target dna binding. the transposase component, whether as part of a fusion protein or supplied in addition to an adapter protein, is capable of catalyzing integrations without the dbd binding to its target. thus, any attempt to target specific sites faces an overwhelming excess of non-specific competitor dna, to which the transposase can freely bind. this non- specific binding of the transposase to human chromosomal dna competes with specific binding to a desired target sequence, thereby limiting the probabilities of targeted transposition events. this problem might be mitigated by engineering of the transposase to reduce its unspecific dna affinity. as sb transposase molecules have a positively charged surface ( ), they readily bind to dna regardless of sequence. decreasing the surface charge of the transposase would likely result in reduced overall activity, but at the same time it might make the transposition reaction more dependent on binding to the target dna by the associated dbd. the ultimate goal would be the design of transposase mutants deficient in target dna binding but proficient in catalysis. a similar approach was previously applied to piggybac transposase mutants deficient in transposon integration. although fusion of a zf dbd restored integration in that study, enrichment of insertion near target sites specified by the dbd was not seen ( ). another simple modification that could potentially result in more efficient targeting is temporal control of the system. in its current form, all components of the system are supplied to the cell at the same time. it might be possible to increase targeting efficiency by supplying the targeting factor first and the transposon only at a later point to provide the targeting factors with more time to bind to their target sites. in conclusion, this study shows that targeting sb transposon integrations towards specific sites in the human genome by an rna-guided mechanism, though currently inefficient, is possible. this is the first time this has been demonstrated for the sb system and the first time rna-guided transposition was demonstrated by analyzing the overall distribution of insertion sites on a genome-wide scale. if the current limitations of the system can be addressed by substantially increasing the efficiency of retargeting, and if these effects can also be observed in therapeutically relevant cell types, this technology might be attractive for a range of applications including therapeutic cell engineering. gene targeting by hr is limited in non-dividing cells because hr is generally active in late s and g phases of the cell cycle ( ). therefore, post- mitotic cells cannot be edited in this manner ( , ). newer gene editing technologies that do not rely on hr, like prime editing ( ), usually have a size limitation for insertions that precludes using them to insert entire genes. in contrast, sb transposition is not limited to dividing cells ( ) and can transfer genes over kb in size ( ). another drawback of methods relying on generating dsbs is the relative unpredictability of the outcome of editing. as described above, different repair pathways can result in different outcomes at the site of a dsb. attempts to insert a genetic sequence using hr can also result in the formation of indels or even complex genomic rearrangements ( ). in contrast to dsb generation followed by hr, insertion by integrating vectors including transposons occurs as a concerted transesterification reaction ( , ), avoiding the problems associated with free dna ends. materials and methods cell culture and transfection in this work we used human hela, hct and hek t cell lines. all cell lines originate from atcc and have tested negative for mycoplasma. hela cells (rrid:cvcl_ ) were cultured at °c and % co in dmem (gibco) supplemented with % (v/v) fcs, mm l-glutamine (sigma) and penicillin-streptomycin. for selection, media were supplemented with puromycin (invivogen) at µg/ml or -thioguanine ( -tg, sigma) at mm. transfections were performed with lipofectamine (invitrogen) according to manufacturer’s instructions. plasmid construction all sequences of primers and other oligos are listed in supplementary file . dcas fusion constructs were generated using pac -dual-dcas vp -sgexpression (addgene, # ) as a starting point. the vp activation domain was removed from this vector by digestion with fsei and ecori. for dcas -sb x, the sb x insert was generated by pcr amplification from a pcmv-sb x expression plasmid with primers sbfwd_ (which introduced the first half of the linker sequence) and sbrev_ (which introduced the ecori site). the resulting product was pcr amplified using sbfwd_ and sbrev_ (sbfwd_ completed the linker sequence and introduced the fsei site). the generated pcr product was purified, digested with ecori and fsei and cloned into the dcas vector. the dcas -n construct was generated in an analogous manner, replacing primer sbrev_ with n rev_ to generate a shorter insert which included a stop codon in front of the ecori site. in addition, annealing of phosphorylated oligos stop_top and stop_btm resulted in a short insert containing a stop codon and sticky ends compatible with fsei- and ecori-digested dna. ligation of this oligo into the fsei/ecori-digested dcas -vp vector resulted in a dcas expression plasmid. to generate the n -dcas plasmid, the previously constructed dcas expression vector was digested with agei and the n sequence was pcr-amplified by two pcrs (using primers sbfwd_ and n rev_ , followed by sbfwd_ and n rev_ ), which introduced a linker and two terminal agei sites. the agei-digested pcr product was ligated into the dcas vector, generating a n -dcas expression vector. for cas -sb x and cas -n constructs, the same cloning strategy was used, using the plasmid pspcas (bb)- a-gfp (addgene, # ) as a starting point instead of pac -dual- dcas vp -sgexpression. insertion of sgrnas into cas /dcas -based vectors was performed by digesting the vector backbone with bbsi and inserting grna target oligos generated by annealing phosphorylated oligos that included overhangs compatible to the bbsi-digested backbones. for expression, plasmids were transformed into e. coli (dh α or top , invitrogen) using a standard heat shock protocol, selected on lb agar plates containing ampicillin and clones were cultured in lb medium with ampicillin. plasmids were isolated using miniprep or midiprep kits (qiagen or zymo, respectively). in vitro cas cleavage assay for in vitro tests of sgrna activities, sgrnas were generated by pcr amplifying the sgrna sequences with a primer introducing a t promoter upstream of the sgrna and performing in vitro transcription using megashortscript™ t transcription kit (thermo fisher). to test the activity of alu-directed sgrnas, µg of genomic dna isolated from human hek t cells (rrid:cvcl_ ) was incubated with µg of in vitro transcribed sgrnas and µg of purified cas protein in µl of x neb buffer (new england biolabs) at °c overnight. dna was visualized by agarose gel electrophoresis in a % agarose gel. after digestion, fragmented gdna was purified using a column purification kit (zymo) and ligated into smai-digested puc . the plasmids were transformed into e. coli dh α and grown on lb agar supplemented with x- gal. plasmids from white colonies were isolated and the insert ends were sequenced using primers puc and puc . sanger sequencing was performed by gatc biotech. the activity of l -directed sgrnas was tested by digesting ng of a plasmid fragment with ng of purified cas and ng of in vitro transcribed sgrna in µl of x neb buffer. the dna substrate was generated by digesting the plasmid containing a full-length l retrotransposon (jm /l . ) with noti-hf (new england biolabs) and isolating the ~ . -kb fragment by gel extraction. tide assay x hela cells were transfected with the plasmid px /hprt (co-expressing cas , sghprt- and a puromycin resistance cassette). after h, selection at µg/ml of puromycin was applied for another h. cells were harvested and genomic dna was prepared using a dneasy blood & tissue kit (qiagen). the hprt locus was amplified using primers hprt_fwd and hprt_rev, pcr products generated from untransfected hela cells served as negative control. pcr products were column-purified and sanger-sequenced using services from gatc biotech with the primer hprt_fwd. the sequences were analyzed using the tide online tool ( ). western blot protein extracts used for western blot were generated by transfecting x hela cells with µg of expression vector dna and lysing cells with ripa buffer after hours. lysates were passed through a -gauge needle, incubated min on ice, then centrifuged at . g and °c for minutes to remove cell debris. total protein concentrations were determined via bradford assay [pierce™ coomassie plus (bradford) assay kit, thermo fisher]. proteins were separated by discontinuous sds-page and transferred onto nitrocellulose membranes ( hour at v). membranes were stained with α-sb antibody (rrid:ab_ , r&d systems, : , hours) and α-goat-hrp (rrid:ab_ , sigma, : , hour) or with α-actin (rrid:ab_ , thermo scientific, : , hours) and α-mouse-hrp (rrid:ab_ , thermo scientific, : , hour) for the loading control. membranes were visualized using ecl™ prime western blotting reagents. transposition assay transposition assays were performed by transfecting hela cells with ng pt bpuro and ng pcmv-sb x or ng of dcas -sb x expression vector. selection was started hours post-transfection in cm dishes. after two weeks, cells were fixed for two hours with % paraformaldehyde, and stained overnight with methylene blue. plates were scanned, and colony numbers were automatically determined using imagej/fiji and the colony counter plugin (settings: size > px, circularity > . ). assay for cas cleavage of the hprt gene for the initial validation of hprt-specific sgrnas, µg each of a plasmid expressing cas and separate plasmids expressing the different sgrnas were transfected into hct cells (rrid:cvcl_ ). for the validation of cas fusion proteins, hct cells were transfected with µg plasmids expressing cas (without sgrna or with sghprt- ), cas -n or cas -sb x (with sghprt- ). selection with mm -tg was started hours after transfection. fixing, staining and counting of colonies were performed as detailed in the previous section. electrophoretic mobility shift assay (emsa) nuclear extracts of hela cells transfected with plasmids expressing dcas , dcas -n and n -dcas were generated using ne-per™ nuclear and cytoplasmic extraction reagents (thermo fisher) according to manufacturer’s instructions, and total protein concentration was determined by bradford assay. similar expression levels between extracts were verified by dot blot using a cas antibody (rrid:ab_ , thermo fisher). a bacterial extract of n was used as a positive control. for the emsa, a lightshift™ chemiluminescent emsa kit (thermo fisher) was used according to manufacturer’s instructions, using ca. µg of total protein (nuclear extracts) or . µg of total protein (bacterial extract). generation of integration libraries sb integrations were generated by transfecting x hela cells with expression plasmids of either dcas -sb x ( ng) or dcas -n ( µg) together with unfused sb x ( ng). all samples were also transfected with . µg of the transposon construct ptpurodr . for each targeting construct, plasmids containing either no sgrna, sghprt- or sgaluy- were used. for libraries using dcas -n and dcas -sb x, two and six independent transfections were performed, respectively. puromycin selection was started hours after transfection and cells were cultured for two weeks. cells were then harvested and pooled from the replicate transfections, and genomic dna was prepared using a dneasy blood & tissue kit (qiagen). the protocol and the oligonucleotides for the construction of the insertion libraries have previously been described ( ). briefly, genomic dna was sonicated to an average length of bp using a covaris m ultrasonicator. fragmented dna was subjected to end repair, da- tailing and linker ligation steps. transposon-genome junctions were then amplified by nested pcrs using two primer pairs binding to the transposon itr and the linker, respectively. the pcr products were separated on a . % ultrapure agarose gel and a size range of - bp was extracted from the gel. some of the generated product was cloned and sanger sequenced for library verification before high-throughput sequencing with a nextseq (illumina) instrument with single-end -bp setting. sequencing and bioinformatic analysis the raw illumina reads were processed in the r environment ( ) as follows: the transposon- specific primer sequences were searched and removed, pcr-specificity was controlled by verifying for the presence of transposon end sequences downstream of the primer. the resulting reads were subjected to adapter-, quality-, and minimum-length-trimming by the fastp algorithm ( ) using the settings below: adapter_sequence =agatcggaagagcacacgtctgaactccagtcac --cut_right --cut_window_size -- cut_mean_quality --length_required . the reads were then mapped to the hg human genome assembly using bowtie ( ) with the --very-fast parameter in --local mode. the ‘unambiguity’ of the mapped insertion site positions were controlled by filtering the sam files using samtools ( ) with the samtools view –q setting. since the mapping allowed for mismatches the insertion sites within nucleotide windows were reduced to the one supported by the highest number of reads. any genomic insertion position was considered valid if supported by at least five independent reads. the genomic coordinates (ucsc hg ) of the transposon integration-site sets of all the conditions are provided as source data files - . insertion site logos were calculated and plotted with the seqlogo package. the frequencies of insertions around the sgrna target sequences were displayed by the genomation package ( ). probability values for nucleosome occupancy in the vicinity of aluy targets and non-targeted insertion sites were calculated with a previously published algorithm ( ). statistical analysis significance of numerical differences in transposition assay and cas cleavage assays was calculated by performing a two-tailed student’s t-test using the graphpad quickcalcs online tool. all experiments that have colony numbers as a readout were performed in triplicates. we used the fishers’ exact test for the statistical analyses of the ta-target contents and the frequencies of insertion sites in various genomic intervals. supplementary data supplementary file figure -figure supplement figure -figure supplement figure -source data - acknowledgements we thank t. diem for technical support. conflict of interest z. i. is co-inventor on patents relating to targeted gene insertion (patent nos. ep b , ep b and ep b ). references . escors, d. and breckpot, k. 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( ) genomation: a toolkit to summarize, annotate and visualize genomic intervals, bioinformatics (oxford, england), , – . table and figures legends figure . general mechanism of dna transposition and molecular strategies for targeted gene integration. (a) the transpositional mechanism of a dna transposon in a biotechnological context. the transgene, which is flanked by transposon itrs (green arrows) is excised from a plasmid by the transposase enzyme (red spheres), which is supplied in trans. the genetic cargo is then integrated in the target genome. (b) transposition can be retargeted by foreign factors that can be dna-binding domains (blue spheres) directly fused to the transposase (red spheres), or to adapter domains (green triangles) that interact either with the transposase (middle) or the transposon dna (bottom). figure . crispr/cas components and their validation for transposon targeting. (a) schematic exon-intron structure of the hprt gene and positions of the sgrna binding sites. (b) numbers of -tg resistant colonies after treatment with cas and hprt-directed sgrnas. significance is calculated in comparison to the no sgrna sample (n= , biological replicates for all samples, * p≤ . , *** p≤ . , error bars represent sem). (c) indel spectrum of the hprt locus after treatment with cas and sghprt- , as determined by tide assay. (d) structure of an alu element and relative positions of sgrna binding sites. (e) agarose gel electrophoresis of human gdna digested with cas and aluy-directed sgrnas. an sgrna targeting the human aavs locus (a single-copy target) as well as samples containing no cas or no sgrna were included as negative controls. (f) sequence logo generated by aligning sequenced gdna ends after fragmentation with cas and sgaluy- (the sequence represents the top strand targeted by the sgrna). the position of the sgrna-binding site and pam is indicated by blue and red background, respectively. the cleavage site is marked by the gray arrow. the sequence upstream of the cleavage site is generated from individual sequences, the sequence downstream is generated from individual sequences. the bottom sequence represents the aluy consensus sequence. figure . transposase-derived targeting factors. (a) schematic representation of the targeting constructs. (b) western blot of proteins expressed by the targeting constructs. the top half of the membrane was treated with α-sb antibody, the bottom half was treated with α-actin as a loading control. dcas was included as a negative control, and is therefore not expected to produce a signal with an antibody against the sb transposase. expected sizes were . kda for dcas -sb x and . kda for dcas -n and n -dcas . figure . functional testing of dcas fusions. (a) numbers of puromycin-resistant colonies in the transposition assay. the dcas -sb x fusion protein catalyzes ~ % as many integration events as unfused sb x transposase (n= , biological replicates, * p≤ . , *** p≤ . , error bars represent sem). (b) emsa with dcas -n fusion proteins. dcas serves as negative control, n as positive control. binding can be detected for dcas -n , but not for n -dcas . the upper band in the positive control lane is likely a multimeric complex of dna-bound n molecules, in line with n ’s documented activity in mediating protein-protein interaction between transposase subunits and in forming higher-order complexes ( ). (c) numbers of -tg resistant colonies after cas cleavage assay. no disruption of the hprt gene, as measured by -tg resistance, can be detected without the addition of an sgrna. in the presence of sghprt- , all cas constructs cause significant disruption of the hprt gene (n= , biological replicates, ** p≤ . , *** p≤ . , error bars represent sem). figure . rna-guided sleeping beauty transposition in human cells. (a) schematic representation of the analysis of sb retargeting. targeting windows are defined as dna extending a certain number of base pairs upstream or downstream of the sgrna target sites (yellow – sgrna target, green – ‘hit’ insertion, red – ‘miss’ insertion). (b) percentages of integrations recovered from windows of different sizes along with the total numbers of integrations in the respective libraries. (c) insertion frequencies relative to the same dataset obtained with sgl - , in windows of various sizes around the targeted sites. slight enrichment can be observed in a -bp window with dcas -n and in a -bp window with dcas - sb x, although neither enrichment is statistically significant. the windows are cumulative, i.e. the -bp window also includes insertions from the -bp window. (d) insertion frequencies in windows of various sizes, relative to a dataset obtained with sgl - , upstream and downstream of the target sites. enrichment with dcas -sb x occurs downstream of the sgrna target site, within a total insertion window of bp (~ . -fold enrichment, p= . ). (e) the effect of the number of mismatches on the targeting efficiency of dcas -sb x. relative insertion frequencies of the dcas -sb x sample into cumulative windows around perfectly matched target sites as well as sites with a single mismatch. figure -figure supplement . design, in vitro validation and impact of sgrnas against human l retrotransposon sequences. (a) schematic representation of the human l retrotransposon and relative positions of the sgrna binding sites. (b) in vitro digestion of a ~ . -kb plasmid fragment carrying the target sites of sgrnas with purified cas and the three l -specific sgrnas. all three sgrnas resulted in digestion of the input dna and the resulting fragments’ relative sizes match the expected values. (c) fractions of insertions into cumulative windows around sgl - target sites. (d) relative insertion frequencies of sb in the presence of sgl - as compared to insertion frequencies of sb in the presence of sgalu- . an overall depletion of insertions and some enrichment in a -bp window downstream of the sgl - binding sites is apparent. however, these ratios are based on only a few insertions falling into the mapping windows, and therefore lack statistical significance. figure -source data . sleeping beauty transposon integration sites obtained with dcas - n +sb x and sgaluy- . figure -source data . sleeping beauty transposon integration sites obtained with dcas - n +sb x and sgl - . figure -source data . sleeping beauty transposon integration sites obtained with dcas - sb x and sgaluy- . figure -source data . sleeping beauty transposon integration sites obtained with dcas - sb x and sgl - . figure . analysis of targeted chromosomal regions. (a) insertion frequencies of the targeted (blue) and non-targeted (red) dataset show that statistically significant (p= . ) enrichment occurs within a -bp window downstream of sites targeted by sgaluy- , which is generally disfavored for sb integration. (b) reduced average ta di-nucleotide frequency the targeted -bp window. (c) computationally predicted nucleosome occupancy around the sites targeted by sgaluy- (blue) and around untargeted sb insertion sites (iss, red). figure -figure supplement . sequence logos generated from sequences around insertion sites catalyzed by dcas -sb x with sgaluy- within the -bp targeting window (left) and outside of the window (right). the left logo has higher variation at most position because of the lower number of insertions. supplementary file . sequences of dna oligos used in this study. article file figure figure figure figure figure figure figure -figure supplement figure -figure supplement can beautiful ideas drive science? in a beautiful question, physicist and nobel laureate frank wilczek makes a potent case that they can, hinging on quali- ties that have served as pathfinders to empir- ical truth in the physical world. the greatest scientists, from galileo to albert einstein, saw in physics almost infinite beauty, includ- ing symmetry, harmony and truth. today, we fervently hope for a genius with a beauty- inspired theory of everything — or at least for the large hadron collider at cern in geneva, switzerland, to discover truth in supersymmetry. a beautiful question is both a brilliant exploration of largely uncharted territories and a refreshingly idiosyncratic guide to developments in particle physics. vast and eclectic, it covers everything from atomism to the higgs boson, musical harmony to anamorphic art, dark matter to the origins of the universe. wilczek lays out a vision of truth and beauty inspired by great modern physicists and classical philosophers such as pythagoras and plato. lavish illustrations exemplifying beauty in art and science, from william blake’s ancient of days to fractal images, are interwoven with quotations from luminaries in the arts and sciences, from molière to john archibald wheeler. wilczek begins with the beauty-inspired seeds sown by the ancient greeks, including the fundamentals of geometry, music and chemistry. the music of the spheres, which pythagoras described as the hum from celestial bodies whose periodicities echoed a harmony that he alone heard, inspired him and his followers to develop harmonies between beauty, music, mathematics and sci- ence. numbers governed all, from octaves to right-angled triangles. through perspec- tive, geometry revolutionized classical, then renaissance, art; through the curvature of space, it revolutionized understanding of gravity. and wilczek argues that colour, the epicentre of beauty, unites art with biology, chemistry and physics. the search for symmetry generated enormous rewards in science, a gift that has kept on giving. in the nineteenth century, michael faraday gave an elegant display of empirical physics by mapping out the pat- terns of magnetic lines of force. he went on to show that moving magnetic fields gener- ate electric fields, motivating mathematical physicist james clerk maxwell to develop his equations for electromagnetism. these epitomized a fundamental symmetry, allow- ing a magnetic field in motion to generate an electric field, and vice versa. the fields prop- agate through space, producing waves of light in all colours of the rainbow. maxwell’s equations also predicted that electromag- netic waves would propagate at frequen- cies beyond perception by the human eye. inspired, heinrich hertz discovered radio waves. beauty had succeeded far beyond any intent of faraday’s. wielding the sword of beauty to refine scientific thought has a remarkable herit- age. einstein put beauty first in conceptual- izing the general theory of relativity. in the dreary postwar climate of , worldwide headlines greeted the successful verification of one of his key pre- dictions — the bend- ing of light by gravity. another triumph is the standard model of particle physics, whose symmetries led to prediction of the higgs boson. wilczek argues that the quantum core of modern physics, the zo o of element ar y p h y s i c s the impulse of beauty joseph silk revels in frank wilczek’s treatise on how symmetry and harmony drive the progress of science. a beautiful question: finding nature’s deep design frank wilczek allen lane: . through the mythological figure of urizen, william blake probed the nature of reductionism. and of us physics in general are well narrated. the newcomers made mistakes and missed opportunities, but european physicists — including such giants as rutherford, james chadwick and pierre and marie curie — maintained a dialogue, and respected them. lawrence and his team stayed engaged, increasingly willing to admit to errors as their confidence grew, and generous with their know-how in help- ing to start other accelerator programmes as the ‘cyclotron republic’ grew. compelling characters abound. there is the mysterious and influential alfred loomis, a patron of science who achieves the feat of “being a public figure without let- ting the public in on it”. later, there is lewis strauss (pronounced ‘straws’), washing- ton dc insider, chair of the atomic energy commission and die-hard opponent of a nuclear-test-ban treaty. lawrence seems to have easily formed bonds with exceptional people, but these sometimes shattered, as with manhattan project leader j. robert oppenheimer, causing damage and dismay. lawrence transformed strikingly from a man who insisted that politics had no place in the lab to one who played high-stakes political games around the credibility of scientific advice on nuclear-weapon devel- opment — and fired outstanding scientists because they refused to sign an oath of loy- alty. the rad lab drew talent, but much of it leaked or was driven away as berkeley became identified with the anti-communist mccarthyism — under which people were branded un-american and unemployable — that abounded in the military–industrial complex that it had helped to create. the final chapter rushes through the for- mation of cern in geneva, swit- zerland, and the failure of its us competitor, the superconducting super collider, which was can- c e l l e d i n t h e s. it is a com- pliment to hiltzik that, having initially wor- ried about the book’s size, i wanted more — in particular, on how cern consciously distanced itself from the military aspect of the complex, and how the teamwork that lawrence developed applies, or fails to, in collaborations of thousands rather than dozens. lawrence had left the scene by then, but his influence still pervades aca- demia, industry and politics. ■ jon butterworth is professor of physics at university college london and writes for the guardian at go.nature.com/qhea i. he is the author of smashing physics. e-mail: j.butterworth@ucl.ac.uk “the rad lab drew talent, but much of it leaked or was driven away as berkeley became identified with mccarthyism.” a k g im a g e s | n a t u r e | v o l | j u l y books & artscomment © macmillan publishers limited. all rights reserved particles, stems from beautiful thoughts framed by appeals to symmetr y. the eightfold way, named by physicist murray gell-mann after the noble eightfold path of buddhism, organizes elementary par- ticles into octets; the higgs, discovered in , is the final missing link in the standard model. now the search is on for a unifying prin- ciple to take us back to simplicity. super- symmetry, the most beautiful idea of all, unites two fundamental types of particles, fermions and bosons, distinguished by their spins. it postulates massive ‘superpartners’ for each particle, the lightest of which is a stable candidate for dark matter. some see a lack of elegance in a theory that has some adjustable degrees of freedom. the sit- uation is, however, being redeemed in part through the enormous efforts of experimen- tal particle physicists to measure many of these numbers. only one real issue remains: at what energies must one smash particles together to seek supersymmetry’s elusive sig- nature? wilczek optimistically predicts that we will discover this holy grail of physics in five years. occasionally the search for beauty has led us astray. science was set back for centuries by the epicycles with which greek astrono- mer ptolemy described planetary motions. modern data debunked fred hoyle’s steady-state theory of the universe. and even particle physics, with its grand hopes of unification, offers no insight into serious cosmological problems such as why dark matter is more than five times as abundant as ordinary matter. most recently there has been string theory, the compellingly beauti- ful union of mathematical simplicity with quantum theory, particle physics and gravity. its advocates have provoked a controversy: can a theory be so beautiful that we award it scientific accolades for its synthetic capacity without an empirical test, or must we dump it on the scrap heap of history for its lack of grounding truth? persistent voices insist that a theory of physics must lead to experimental verifi- cation. wilczek is emphatic about this, as was isaac newton, who would like us to see empiricism as the search for truth. if truth and beauty are inseparable, that circle is closed. that is where supersymmetry will rise or fall. i hope for the latter, although i am reconciled to waiting for a new generation of unprecedentedly powerful particle col- liders to reach the frontiers of our unifying theory. ■ joseph silk is at the institut d’astrophysique de paris, the beecroft institute for particle astrophysics and cosmology in oxford, uk, and the johns hopkins university in baltimore, maryland. e-mail: joseph.silk@physics.ox.ac.uk let’s be less stupid: an attempt to maintain my mental faculties patricia marx twelve ( ) struggling with brain fog? this “sub-primer” on the neuroscience of intelligence and memory by new yorker staff writer and master humorist patricia marx delivers salutary cognitive jolts amid the general hilarity. through a “higgledy-piggledy assortment of highfalutin science, lowfalutin sciences, tests” and more, marx explores memory slippage, mindfulness, the cherokee language and brain scans. if you regularly arrive in rooms with no memory of what you were looking for, this one is for you. barbara kiser a dangerous master: how to keep technology from slipping beyond our control wendell wallach basic ( ) hordes of technologies emerge in lockstep with warnings of their risks. ethicist wendell wallach sorts the hysteria from the hazards in this magisterial study. he looks in turn at disruption, complex systems, problematic trade-offs, the “transhumanism” movement — and new forms of governance to guide us through the innovatory onrush. it is conscious engagement, wallach argues, that will allow us to resist the truly dangerous developments that threaten to “woo us to sleepwalk into the technological wonderland”. secret science: a century of poison warfare and human experiments ulf schmidt oxford university press ( ) this monumental history of twentieth-century military medical ethics is a meticulous record of ambiguity. historian ulf schmidt shows how germany’s use of chemical weapons such as mustard gas in the first world war spurred britain, canada and the united states to begin secret toxic-agent trials that purported, in some cases, to be benign medical testing. at the uk porton down research centre alone, schmidt reveals, , soldiers took part in tests between and — an experience that was frequently unpleasant, occasionally harmful and in a few cases fatal. discovering tuberculosis: a global history, to the present christian w. mcmillen yale university press ( ) polio incidence is down by % since , but tuberculosis (tb) remains a scourge; it kills million people a year, most with hiv/aids. in his chronicle of tb’s trajectory from the start of the twentieth century, historian christian mcmillen probes our failure to control this “resilient, powerful, protean bacterial infection” and its drug-resistant strains. tracing the swathe tb has cut through africa, india and native american areas, mcmillen identifies the catalogue of errors keeping it in circulation — such as the closure of the uk medical research council’s tb units in , just as africa’s struggle with hiv began. planck: driven by vision, broken by war brandon r. brown oxford university press ( ) the life of max planck, ‘father of quantum theory’, smacks of enigma: his personal papers were mostly destroyed in the second world war. physicist brandon brown has mined what survived for this illuminating biography. the main thread is the endgame of the second world war, when the elderly planck endured tribulations such as his son erwin’s trial and execution for treason against the reich. through this brown interweaves a gripping backstory, ranging from planck’s landmark theoretical description of black- body radiation to his loyal advocacy for fellow physicist lise meitner. books & arts comment j u l y | v o l | n a t u r e | books in brief © macmillan publishers limited. all rights reserved physics: the impulse of beauty references beautiful blue world by suzanne lafleur (review) beautiful blue world by suzanne lafleur (review) amy atkinson bulletin of the center for children's books, volume , number , september , p. (review) published by johns hopkins university press doi: for additional information about this article [ access provided at apr : gmt from carnegie mellon university ] https://doi.org/ . /bcc. . https://muse.jhu.edu/article/ https://doi.org/ . /bcc. . https://muse.jhu.edu/article/ • the bulletin lafleur, suzanne beautiful blue world. lamb, [ p] library ed. isbn - - - - $ . trade ed. isbn - - - - $ . e-book ed. isbn - - - - $ . reviewed from galleys r gr. - for twelve-year old mathilde, her country of sofarende’s war with neighboring tyssia means rations and nightly air raids; at least she has megs, her lifelong best friend, to huddle with in the bunker. then a government recruitment program seeks out the best minds among sofarende’s youth, promising to not only house and feed participants but also send money to their families regularly. certain that high-achieving megs will win a coveted spot, mathilde is baffled to learn instead of her own selection to the program. she soon finds herself in a remote military outpost disguised as a school, where children break codes, anticipate tyssia’s maneuvers, and advise as tacticians, and where she is tasked with speaking with a prisoner of war housed in the school. as she learns strength and independence, she also learns the value of her interpersonal abilities in this poignant and inspiring examination of resilience and respectful celebration of soft skills. the scandinavian-eque set- ting provides an atmospheric but unobtrusive backdrop to mathilde’s external and internal journeys; indeed, lack of elaborate description of the fictional sofarende and tyssia allows the reader to see the ambiguities and complexities of war and its effect on all involved. though mathilde makes much of her relationship with megs, this book is really about her own self-discovery and inner resources—a gentle read, despite the wartime backdrop, for kids wanting a touch of adventure in their stories of friendship and personal growth. aa lariviere, sarah the bad kid. simon, [ p] trade ed. isbn - - - - $ . e-book ed. isbn - - - - $ . reviewed from galleys r gr. - the term “hot mess” could have been coined specifically for eleven-year-old claudeline. her much-pierced and tattooed dad, considered the family weakling by his own now-deceased chinese gangster father, is distracted; her steely mom vacillates between stand-offish and downright erratic; and worst of all, best buddy brett is on hiatus from her drama, actually running away from her with his nose in a book of chinese philosophy. claude finds solace hanging with phil and rita, the bartender and aspiring screenwriter customer at the restaurant where mom works. claude’s sassy mouth and wild stories delight phil and rita, but the tales provide thin cover for her inner emotional turmoil and self doubt. enter alma lingonberry, a dying girl who wants to spend the final days of her illness cultivating , friendships—or at least that’s what the fliers posted around town claim. although claude is skeptical, even holding in contempt the grownups who are falling for the probable scam, her email correspondence with alma provides a new focus. in her pursuit of the truth, claude reclaims faltering relationships with family and friends and solves a darn good little mystery into the bargain. catching the rhythm of tall tales, defiance, and introspection that is claude’s narrative style may take a couple of chapters, but it’s well worth the effort, and untangling the effect alma lingonberry has on claude’s circle leads readers not only to a satisfying conclusion but also to musings on the relationship between fact and truth. eb [pdf] beauty and the belles | semantic scholar skip to search formskip to main content> semantic scholar's logo search sign increate free account you are currently offline. some features of the site may not work correctly. doi: . / corpus id: beauty and the belles @article{craven beautyat, title={beauty and the belles}, author={a. craven}, journal={european journal of women's studies}, year={ }, volume={ }, pages={ - } } a. craven published sociology european journal of women's studies this article presents a critical analysis of disney's animated film and stage production of beauty and the beast, especially of the heroine, belle, within a more general and brief historiography of the fairy tale. it is argued that disney's version displaces the heroic focus from belle (beauty) to beast, while also narrating a response to feminism that involves compressing feminist ideology into conventions of popular romance. the broader representation of femininity in disney is also examined… expand view on sage web .uwindsor.ca save to library create alert cite launch research feed share this paper citationshighly influential citations background citations methods citations view all paper mentions blog post is emma watson’s belle the feminist heroine deserves? pacific standard. smart journalism. real solutions. march citations citation type citation type all types cites results cites methods cites background has pdf publication type author more filters more filters filters sort by relevance sort by most influenced papers sort by citation count sort by recency beauties in an ugly world: the evolution of feminism in adaptations of jeanne-marie leprince de beaumont’s beauty and the beast d. andrade art pdf save alert research feed disney's violent women : in quest of a 'fully real' violent woman in american cinema z. tóth history save alert research feed repackaging the disney princess: a post-feminist reading of modern day fairy tales s. wilde art save alert research feed passively ever after : disney's cinematic abuse in beauty and the beast erin michelle lederer psychology view excerpt, cites background save alert research feed an epideictic dimension of symbolic violence in disney's beauty and the beast: inter-generational lessons in romanticizing and tolerating intimate partner violence kathryn m. olson sociology view excerpt, cites background save alert research feed are disney characters ‘frozen’ in stereotypes? an intersectional analysis of frozen a. rogers sociology view excerpts, cites background save alert research feed growing up with disney: gender representation and spectatorship of fairy-tale cinemas fei jiun kik art save alert research feed the construction of family in selected disney animated films b. balraj, k. gopal art pdf view excerpt, cites background save alert research feed princess bodies, commodities for the wicked. a marxist reading of disney's animated films the little mermaid ( ) and tangled ( ) ana-maria niculescu-mizil art save alert research feed weaving words a diachronic analysis of the representation of gender, sexuality and otherness in women’s (re)writings of la belle et la bête d. mcgrath art pdf save alert research feed ... ... references showing - of references sort byrelevance most influenced papers recency on longing: narratives of the miniature, the gigantic, the souvenir, the collection s. stewart art , save alert research feed studies in entertainment: critical approaches to mass culture tania modleski art save alert research feed the madwoman in the attic: the woman writer and the nineteenth-century literary imagination. annette kolodny, s. gilbert, s. gubar history, art , highly influential view excerpts, references background save alert research feed from the beast to the blonde: on fairy tales and their tellers j. conrad, m. warner art, history save alert research feed morphology of the folktale v. propp, svatava pirkova-jakobson, l. scott history, psychology , view excerpt, references background save alert research feed the case of peter pan, or, the impossibility of children's fiction j. rose art, philosophy save alert research feed alice doesn't: feminism, semiotics, cinema b. knapp, t. lauretis sociology, art highly influential view excerpts, references background save alert research feed the dialogic imagination: four essays m. ehre, m. bakhtin, m. holquist, c. emerson sociology , pdf save alert research feed alice doesn't: feminism alice doesn’t teresa de lauretis sociology highly influential view excerpts, references background save alert research feed ... ... related papers abstract paper mentions citations references related papers stay connected with semantic scholar sign up about semantic scholar semantic scholar is a free, ai-powered research tool for scientific literature, based at the allen institute for ai. learn more → resources datasetssupp.aiapiopen corpus organization about usresearchpublishing partnersdata partners faqcontact proudly built by ai with the help of our collaborators blog posts, news articles and tweet counts and ids sourced by altmetric.com terms of service•privacy policy the allen institute for ai by clicking accept or continuing to use the site, you agree to the terms outlined in our privacy policy, terms of service, and dataset license accept & continue